diff options
Diffstat (limited to 'fs/ubifs')
| -rw-r--r-- | fs/ubifs/Makefile | 52 | ||||
| -rw-r--r-- | fs/ubifs/budget.c | 113 | ||||
| -rw-r--r-- | fs/ubifs/crc16.c | 60 | ||||
| -rw-r--r-- | fs/ubifs/crc16.h | 30 | ||||
| -rw-r--r-- | fs/ubifs/debug.c | 156 | ||||
| -rw-r--r-- | fs/ubifs/debug.h | 392 | ||||
| -rw-r--r-- | fs/ubifs/io.c | 316 | ||||
| -rw-r--r-- | fs/ubifs/key.h | 557 | ||||
| -rw-r--r-- | fs/ubifs/log.c | 104 | ||||
| -rw-r--r-- | fs/ubifs/lprops.c | 842 | ||||
| -rw-r--r-- | fs/ubifs/lpt.c | 1105 | ||||
| -rw-r--r-- | fs/ubifs/lpt_commit.c | 171 | ||||
| -rw-r--r-- | fs/ubifs/master.c | 341 | ||||
| -rw-r--r-- | fs/ubifs/misc.h | 310 | ||||
| -rw-r--r-- | fs/ubifs/orphan.c | 316 | ||||
| -rw-r--r-- | fs/ubifs/recovery.c | 1249 | ||||
| -rw-r--r-- | fs/ubifs/replay.c | 1070 | ||||
| -rw-r--r-- | fs/ubifs/sb.c | 324 | ||||
| -rw-r--r-- | fs/ubifs/scan.c | 362 | ||||
| -rw-r--r-- | fs/ubifs/super.c | 1189 | ||||
| -rw-r--r-- | fs/ubifs/tnc.c | 2767 | ||||
| -rw-r--r-- | fs/ubifs/tnc_commit.c | 1102 | ||||
| -rw-r--r-- | fs/ubifs/tnc_misc.c | 435 | ||||
| -rw-r--r-- | fs/ubifs/ubifs-media.h | 751 | ||||
| -rw-r--r-- | fs/ubifs/ubifs.c | 687 | ||||
| -rw-r--r-- | fs/ubifs/ubifs.h | 2173 |
26 files changed, 16974 insertions, 0 deletions
diff --git a/fs/ubifs/Makefile b/fs/ubifs/Makefile new file mode 100644 index 0000000..8328843 --- /dev/null +++ b/fs/ubifs/Makefile @@ -0,0 +1,52 @@ +# +# (C) Copyright 2006 +# Wolfgang Denk, DENX Software Engineering, wd@denx.de. +# +# (C) Copyright 2003 +# Pavel Bartusek, Sysgo Real-Time Solutions AG, pba@sysgo.de +# +# +# See file CREDITS for list of people who contributed to this +# project. +# +# This program is free software; you can redistribute it and/or +# modify it under the terms of the GNU General Public License as +# published by the Free Software Foundation; either version 2 of +# the License, or (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 59 Temple Place, Suite 330, Boston, +# MA 02111-1307 USA +# + +include $(TOPDIR)/config.mk + +LIB = $(obj)libubifs.a + +COBJS-$(CONFIG_CMD_UBIFS) := ubifs.o io.o super.o sb.o master.o lpt.o +COBJS-$(CONFIG_CMD_UBIFS) += lpt_commit.o scan.o lprops.o +COBJS-$(CONFIG_CMD_UBIFS) += tnc.o tnc_misc.o debug.o crc16.o budget.o +COBJS-$(CONFIG_CMD_UBIFS) += log.o orphan.o recovery.o replay.o + +SRCS := $(AOBJS:.o=.S) $(COBJS-y:.o=.c) +OBJS := $(addprefix $(obj),$(AOBJS) $(COBJS-y)) + +all: $(LIB) $(AOBJS) + +$(LIB): $(obj).depend $(OBJS) + $(AR) $(ARFLAGS) $@ $(OBJS) + +######################################################################### + +# defines $(obj).depend target +include $(SRCTREE)/rules.mk + +sinclude $(obj).depend + +######################################################################### diff --git a/fs/ubifs/budget.c b/fs/ubifs/budget.c new file mode 100644 index 0000000..85377ea --- /dev/null +++ b/fs/ubifs/budget.c @@ -0,0 +1,113 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements the budgeting sub-system which is responsible for UBIFS + * space management. + * + * Factors such as compression, wasted space at the ends of LEBs, space in other + * journal heads, the effect of updates on the index, and so on, make it + * impossible to accurately predict the amount of space needed. Consequently + * approximations are used. + */ + +#include "ubifs.h" +#include <linux/math64.h> + +/** + * ubifs_calc_min_idx_lebs - calculate amount of eraseblocks for the index. + * @c: UBIFS file-system description object + * + * This function calculates and returns the number of eraseblocks which should + * be kept for index usage. + */ +int ubifs_calc_min_idx_lebs(struct ubifs_info *c) +{ + int idx_lebs, eff_leb_size = c->leb_size - c->max_idx_node_sz; + long long idx_size; + + idx_size = c->old_idx_sz + c->budg_idx_growth + c->budg_uncommitted_idx; + + /* And make sure we have thrice the index size of space reserved */ + idx_size = idx_size + (idx_size << 1); + + /* + * We do not maintain 'old_idx_size' as 'old_idx_lebs'/'old_idx_bytes' + * pair, nor similarly the two variables for the new index size, so we + * have to do this costly 64-bit division on fast-path. + */ + idx_size += eff_leb_size - 1; + idx_lebs = div_u64(idx_size, eff_leb_size); + /* + * The index head is not available for the in-the-gaps method, so add an + * extra LEB to compensate. + */ + idx_lebs += 1; + if (idx_lebs < MIN_INDEX_LEBS) + idx_lebs = MIN_INDEX_LEBS; + return idx_lebs; +} + +/** + * ubifs_reported_space - calculate reported free space. + * @c: the UBIFS file-system description object + * @free: amount of free space + * + * This function calculates amount of free space which will be reported to + * user-space. User-space application tend to expect that if the file-system + * (e.g., via the 'statfs()' call) reports that it has N bytes available, they + * are able to write a file of size N. UBIFS attaches node headers to each data + * node and it has to write indexing nodes as well. This introduces additional + * overhead, and UBIFS has to report slightly less free space to meet the above + * expectations. + * + * This function assumes free space is made up of uncompressed data nodes and + * full index nodes (one per data node, tripled because we always allow enough + * space to write the index thrice). + * + * Note, the calculation is pessimistic, which means that most of the time + * UBIFS reports less space than it actually has. + */ +long long ubifs_reported_space(const struct ubifs_info *c, long long free) +{ + int divisor, factor, f; + + /* + * Reported space size is @free * X, where X is UBIFS block size + * divided by UBIFS block size + all overhead one data block + * introduces. The overhead is the node header + indexing overhead. + * + * Indexing overhead calculations are based on the following formula: + * I = N/(f - 1) + 1, where I - number of indexing nodes, N - number + * of data nodes, f - fanout. Because effective UBIFS fanout is twice + * as less than maximum fanout, we assume that each data node + * introduces 3 * @c->max_idx_node_sz / (@c->fanout/2 - 1) bytes. + * Note, the multiplier 3 is because UBIFS reserves thrice as more space + * for the index. + */ + f = c->fanout > 3 ? c->fanout >> 1 : 2; + factor = UBIFS_BLOCK_SIZE; + divisor = UBIFS_MAX_DATA_NODE_SZ; + divisor += (c->max_idx_node_sz * 3) / (f - 1); + free *= factor; + return div_u64(free, divisor); +} diff --git a/fs/ubifs/crc16.c b/fs/ubifs/crc16.c new file mode 100644 index 0000000..443ccf8 --- /dev/null +++ b/fs/ubifs/crc16.c @@ -0,0 +1,60 @@ +/* + * crc16.c + * + * This source code is licensed under the GNU General Public License, + * Version 2. See the file COPYING for more details. + */ + +#include <linux/types.h> +#include "crc16.h" + +/** CRC table for the CRC-16. The poly is 0x8005 (x^16 + x^15 + x^2 + 1) */ +u16 const crc16_table[256] = { + 0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241, + 0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440, + 0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40, + 0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841, + 0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40, + 0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41, + 0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641, + 0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040, + 0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240, + 0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441, + 0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41, + 0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840, + 0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41, + 0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40, + 0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640, + 0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041, + 0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240, + 0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441, + 0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41, + 0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840, + 0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41, + 0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40, + 0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640, + 0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041, + 0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241, + 0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440, + 0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40, + 0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841, + 0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40, + 0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41, + 0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641, + 0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040 +}; + +/** + * crc16 - compute the CRC-16 for the data buffer + * @crc: previous CRC value + * @buffer: data pointer + * @len: number of bytes in the buffer + * + * Returns the updated CRC value. + */ +u16 crc16(u16 crc, u8 const *buffer, size_t len) +{ + while (len--) + crc = crc16_byte(crc, *buffer++); + return crc; +} diff --git a/fs/ubifs/crc16.h b/fs/ubifs/crc16.h new file mode 100644 index 0000000..9443c08 --- /dev/null +++ b/fs/ubifs/crc16.h @@ -0,0 +1,30 @@ +/* + * crc16.h - CRC-16 routine + * + * Implements the standard CRC-16: + * Width 16 + * Poly 0x8005 (x^16 + x^15 + x^2 + 1) + * Init 0 + * + * Copyright (c) 2005 Ben Gardner <bgardner@wabtec.com> + * + * This source code is licensed under the GNU General Public License, + * Version 2. See the file COPYING for more details. + */ + +#ifndef __CRC16_H +#define __CRC16_H + +#include <linux/types.h> + +extern u16 const crc16_table[256]; + +extern u16 crc16(u16 crc, const u8 *buffer, size_t len); + +static inline u16 crc16_byte(u16 crc, const u8 data) +{ + return (crc >> 8) ^ crc16_table[(crc ^ data) & 0xff]; +} + +#endif /* __CRC16_H */ + diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c new file mode 100644 index 0000000..6afb883 --- /dev/null +++ b/fs/ubifs/debug.c @@ -0,0 +1,156 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file implements most of the debugging stuff which is compiled in only + * when it is enabled. But some debugging check functions are implemented in + * corresponding subsystem, just because they are closely related and utilize + * various local functions of those subsystems. + */ + +#define UBIFS_DBG_PRESERVE_UBI + +#include "ubifs.h" + +#ifdef CONFIG_UBIFS_FS_DEBUG + +DEFINE_SPINLOCK(dbg_lock); + +static char dbg_key_buf0[128]; +static char dbg_key_buf1[128]; + +unsigned int ubifs_msg_flags = UBIFS_MSG_FLAGS_DEFAULT; +unsigned int ubifs_chk_flags = UBIFS_CHK_FLAGS_DEFAULT; +unsigned int ubifs_tst_flags; + +module_param_named(debug_msgs, ubifs_msg_flags, uint, S_IRUGO | S_IWUSR); +module_param_named(debug_chks, ubifs_chk_flags, uint, S_IRUGO | S_IWUSR); +module_param_named(debug_tsts, ubifs_tst_flags, uint, S_IRUGO | S_IWUSR); + +MODULE_PARM_DESC(debug_msgs, "Debug message type flags"); +MODULE_PARM_DESC(debug_chks, "Debug check flags"); +MODULE_PARM_DESC(debug_tsts, "Debug special test flags"); + +static const char *get_key_type(int type) +{ + switch (type) { + case UBIFS_INO_KEY: + return "inode"; + case UBIFS_DENT_KEY: + return "direntry"; + case UBIFS_XENT_KEY: + return "xentry"; + case UBIFS_DATA_KEY: + return "data"; + case UBIFS_TRUN_KEY: + return "truncate"; + default: + return "unknown/invalid key"; + } +} + +static void sprintf_key(const struct ubifs_info *c, const union ubifs_key *key, + char *buffer) +{ + char *p = buffer; + int type = key_type(c, key); + + if (c->key_fmt == UBIFS_SIMPLE_KEY_FMT) { + switch (type) { + case UBIFS_INO_KEY: + sprintf(p, "(%lu, %s)", (unsigned long)key_inum(c, key), + get_key_type(type)); + break; + case UBIFS_DENT_KEY: + case UBIFS_XENT_KEY: + sprintf(p, "(%lu, %s, %#08x)", + (unsigned long)key_inum(c, key), + get_key_type(type), key_hash(c, key)); + break; + case UBIFS_DATA_KEY: + sprintf(p, "(%lu, %s, %u)", + (unsigned long)key_inum(c, key), + get_key_type(type), key_block(c, key)); + break; + case UBIFS_TRUN_KEY: + sprintf(p, "(%lu, %s)", + (unsigned long)key_inum(c, key), + get_key_type(type)); + break; + default: + sprintf(p, "(bad key type: %#08x, %#08x)", + key->u32[0], key->u32[1]); + } + } else + sprintf(p, "bad key format %d", c->key_fmt); +} + +const char *dbg_key_str0(const struct ubifs_info *c, const union ubifs_key *key) +{ + /* dbg_lock must be held */ + sprintf_key(c, key, dbg_key_buf0); + return dbg_key_buf0; +} + +const char *dbg_key_str1(const struct ubifs_info *c, const union ubifs_key *key) +{ + /* dbg_lock must be held */ + sprintf_key(c, key, dbg_key_buf1); + return dbg_key_buf1; +} + +/** + * ubifs_debugging_init - initialize UBIFS debugging. + * @c: UBIFS file-system description object + * + * This function initializes debugging-related data for the file system. + * Returns zero in case of success and a negative error code in case of + * failure. + */ +int ubifs_debugging_init(struct ubifs_info *c) +{ + c->dbg = kzalloc(sizeof(struct ubifs_debug_info), GFP_KERNEL); + if (!c->dbg) + return -ENOMEM; + + c->dbg->buf = vmalloc(c->leb_size); + if (!c->dbg->buf) + goto out; + + return 0; + +out: + kfree(c->dbg); + return -ENOMEM; +} + +/** + * ubifs_debugging_exit - free debugging data. + * @c: UBIFS file-system description object + */ +void ubifs_debugging_exit(struct ubifs_info *c) +{ + vfree(c->dbg->buf); + kfree(c->dbg); +} + +#endif /* CONFIG_UBIFS_FS_DEBUG */ diff --git a/fs/ubifs/debug.h b/fs/ubifs/debug.h new file mode 100644 index 0000000..62617b6 --- /dev/null +++ b/fs/ubifs/debug.h @@ -0,0 +1,392 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +#ifndef __UBIFS_DEBUG_H__ +#define __UBIFS_DEBUG_H__ + +#ifdef CONFIG_UBIFS_FS_DEBUG + +/** + * ubifs_debug_info - per-FS debugging information. + * @buf: a buffer of LEB size, used for various purposes + * @old_zroot: old index root - used by 'dbg_check_old_index()' + * @old_zroot_level: old index root level - used by 'dbg_check_old_index()' + * @old_zroot_sqnum: old index root sqnum - used by 'dbg_check_old_index()' + * @failure_mode: failure mode for recovery testing + * @fail_delay: 0=>don't delay, 1=>delay a time, 2=>delay a number of calls + * @fail_timeout: time in jiffies when delay of failure mode expires + * @fail_cnt: current number of calls to failure mode I/O functions + * @fail_cnt_max: number of calls by which to delay failure mode + * @chk_lpt_sz: used by LPT tree size checker + * @chk_lpt_sz2: used by LPT tree size checker + * @chk_lpt_wastage: used by LPT tree size checker + * @chk_lpt_lebs: used by LPT tree size checker + * @new_nhead_offs: used by LPT tree size checker + * @new_ihead_lnum: used by debugging to check @c->ihead_lnum + * @new_ihead_offs: used by debugging to check @c->ihead_offs + * + * @saved_lst: saved lprops statistics (used by 'dbg_save_space_info()') + * @saved_free: saved free space (used by 'dbg_save_space_info()') + * + * dfs_dir_name: name of debugfs directory containing this file-system's files + * dfs_dir: direntry object of the file-system debugfs directory + * dfs_dump_lprops: "dump lprops" debugfs knob + * dfs_dump_budg: "dump budgeting information" debugfs knob + * dfs_dump_tnc: "dump TNC" debugfs knob + */ +struct ubifs_debug_info { + void *buf; + struct ubifs_zbranch old_zroot; + int old_zroot_level; + unsigned long long old_zroot_sqnum; + int failure_mode; + int fail_delay; + unsigned long fail_timeout; + unsigned int fail_cnt; + unsigned int fail_cnt_max; + long long chk_lpt_sz; + long long chk_lpt_sz2; + long long chk_lpt_wastage; + int chk_lpt_lebs; + int new_nhead_offs; + int new_ihead_lnum; + int new_ihead_offs; + + struct ubifs_lp_stats saved_lst; + long long saved_free; + + char dfs_dir_name[100]; + struct dentry *dfs_dir; + struct dentry *dfs_dump_lprops; + struct dentry *dfs_dump_budg; + struct dentry *dfs_dump_tnc; +}; + +#define UBIFS_DBG(op) op + +#define ubifs_assert(expr) do { \ + if (unlikely(!(expr))) { \ + printk(KERN_CRIT "UBIFS assert failed in %s at %u (pid %d)\n", \ + __func__, __LINE__, 0); \ + dbg_dump_stack(); \ + } \ +} while (0) + +#define ubifs_assert_cmt_locked(c) do { \ + if (unlikely(down_write_trylock(&(c)->commit_sem))) { \ + up_write(&(c)->commit_sem); \ + printk(KERN_CRIT "commit lock is not locked!\n"); \ + ubifs_assert(0); \ + } \ +} while (0) + +#define dbg_dump_stack() do { \ + if (!dbg_failure_mode) \ + dump_stack(); \ +} while (0) + +/* Generic debugging messages */ +#define dbg_msg(fmt, ...) do { \ + spin_lock(&dbg_lock); \ + printk(KERN_DEBUG "UBIFS DBG (pid %d): %s: " fmt "\n", 0, \ + __func__, ##__VA_ARGS__); \ + spin_unlock(&dbg_lock); \ +} while (0) + +#define dbg_do_msg(typ, fmt, ...) do { \ + if (ubifs_msg_flags & typ) \ + dbg_msg(fmt, ##__VA_ARGS__); \ +} while (0) + +#define dbg_err(fmt, ...) do { \ + spin_lock(&dbg_lock); \ + ubifs_err(fmt, ##__VA_ARGS__); \ + spin_unlock(&dbg_lock); \ +} while (0) + +const char *dbg_key_str0(const struct ubifs_info *c, + const union ubifs_key *key); +const char *dbg_key_str1(const struct ubifs_info *c, + const union ubifs_key *key); + +/* + * DBGKEY macros require @dbg_lock to be held, which it is in the dbg message + * macros. + */ +#define DBGKEY(key) dbg_key_str0(c, (key)) +#define DBGKEY1(key) dbg_key_str1(c, (key)) + +/* General messages */ +#define dbg_gen(fmt, ...) dbg_do_msg(UBIFS_MSG_GEN, fmt, ##__VA_ARGS__) + +/* Additional journal messages */ +#define dbg_jnl(fmt, ...) dbg_do_msg(UBIFS_MSG_JNL, fmt, ##__VA_ARGS__) + +/* Additional TNC messages */ +#define dbg_tnc(fmt, ...) dbg_do_msg(UBIFS_MSG_TNC, fmt, ##__VA_ARGS__) + +/* Additional lprops messages */ +#define dbg_lp(fmt, ...) dbg_do_msg(UBIFS_MSG_LP, fmt, ##__VA_ARGS__) + +/* Additional LEB find messages */ +#define dbg_find(fmt, ...) dbg_do_msg(UBIFS_MSG_FIND, fmt, ##__VA_ARGS__) + +/* Additional mount messages */ +#define dbg_mnt(fmt, ...) dbg_do_msg(UBIFS_MSG_MNT, fmt, ##__VA_ARGS__) + +/* Additional I/O messages */ +#define dbg_io(fmt, ...) dbg_do_msg(UBIFS_MSG_IO, fmt, ##__VA_ARGS__) + +/* Additional commit messages */ +#define dbg_cmt(fmt, ...) dbg_do_msg(UBIFS_MSG_CMT, fmt, ##__VA_ARGS__) + +/* Additional budgeting messages */ +#define dbg_budg(fmt, ...) dbg_do_msg(UBIFS_MSG_BUDG, fmt, ##__VA_ARGS__) + +/* Additional log messages */ +#define dbg_log(fmt, ...) dbg_do_msg(UBIFS_MSG_LOG, fmt, ##__VA_ARGS__) + +/* Additional gc messages */ +#define dbg_gc(fmt, ...) dbg_do_msg(UBIFS_MSG_GC, fmt, ##__VA_ARGS__) + +/* Additional scan messages */ +#define dbg_scan(fmt, ...) dbg_do_msg(UBIFS_MSG_SCAN, fmt, ##__VA_ARGS__) + +/* Additional recovery messages */ +#define dbg_rcvry(fmt, ...) dbg_do_msg(UBIFS_MSG_RCVRY, fmt, ##__VA_ARGS__) + +/* + * Debugging message type flags (must match msg_type_names in debug.c). + * + * UBIFS_MSG_GEN: general messages + * UBIFS_MSG_JNL: journal messages + * UBIFS_MSG_MNT: mount messages + * UBIFS_MSG_CMT: commit messages + * UBIFS_MSG_FIND: LEB find messages + * UBIFS_MSG_BUDG: budgeting messages + * UBIFS_MSG_GC: garbage collection messages + * UBIFS_MSG_TNC: TNC messages + * UBIFS_MSG_LP: lprops messages + * UBIFS_MSG_IO: I/O messages + * UBIFS_MSG_LOG: log messages + * UBIFS_MSG_SCAN: scan messages + * UBIFS_MSG_RCVRY: recovery messages + */ +enum { + UBIFS_MSG_GEN = 0x1, + UBIFS_MSG_JNL = 0x2, + UBIFS_MSG_MNT = 0x4, + UBIFS_MSG_CMT = 0x8, + UBIFS_MSG_FIND = 0x10, + UBIFS_MSG_BUDG = 0x20, + UBIFS_MSG_GC = 0x40, + UBIFS_MSG_TNC = 0x80, + UBIFS_MSG_LP = 0x100, + UBIFS_MSG_IO = 0x200, + UBIFS_MSG_LOG = 0x400, + UBIFS_MSG_SCAN = 0x800, + UBIFS_MSG_RCVRY = 0x1000, +}; + +/* Debugging message type flags for each default debug message level */ +#define UBIFS_MSG_LVL_0 0 +#define UBIFS_MSG_LVL_1 0x1 +#define UBIFS_MSG_LVL_2 0x7f +#define UBIFS_MSG_LVL_3 0xffff + +/* + * Debugging check flags (must match chk_names in debug.c). + * + * UBIFS_CHK_GEN: general checks + * UBIFS_CHK_TNC: check TNC + * UBIFS_CHK_IDX_SZ: check index size + * UBIFS_CHK_ORPH: check orphans + * UBIFS_CHK_OLD_IDX: check the old index + * UBIFS_CHK_LPROPS: check lprops + * UBIFS_CHK_FS: check the file-system + */ +enum { + UBIFS_CHK_GEN = 0x1, + UBIFS_CHK_TNC = 0x2, + UBIFS_CHK_IDX_SZ = 0x4, + UBIFS_CHK_ORPH = 0x8, + UBIFS_CHK_OLD_IDX = 0x10, + UBIFS_CHK_LPROPS = 0x20, + UBIFS_CHK_FS = 0x40, +}; + +/* + * Special testing flags (must match tst_names in debug.c). + * + * UBIFS_TST_FORCE_IN_THE_GAPS: force the use of in-the-gaps method + * UBIFS_TST_RCVRY: failure mode for recovery testing + */ +enum { + UBIFS_TST_FORCE_IN_THE_GAPS = 0x2, + UBIFS_TST_RCVRY = 0x4, +}; + +#if CONFIG_UBIFS_FS_DEBUG_MSG_LVL == 1 +#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_1 +#elif CONFIG_UBIFS_FS_DEBUG_MSG_LVL == 2 +#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_2 +#elif CONFIG_UBIFS_FS_DEBUG_MSG_LVL == 3 +#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_3 +#else +#define UBIFS_MSG_FLAGS_DEFAULT UBIFS_MSG_LVL_0 +#endif + +#ifdef CONFIG_UBIFS_FS_DEBUG_CHKS +#define UBIFS_CHK_FLAGS_DEFAULT 0xffffffff +#else +#define UBIFS_CHK_FLAGS_DEFAULT 0 +#endif + +#define dbg_ntype(type) "" +#define dbg_cstate(cmt_state) "" +#define dbg_get_key_dump(c, key) ({}) +#define dbg_dump_inode(c, inode) ({}) +#define dbg_dump_node(c, node) ({}) +#define dbg_dump_budget_req(req) ({}) +#define dbg_dump_lstats(lst) ({}) +#define dbg_dump_budg(c) ({}) +#define dbg_dump_lprop(c, lp) ({}) +#define dbg_dump_lprops(c) ({}) +#define dbg_dump_lpt_info(c) ({}) +#define dbg_dump_leb(c, lnum) ({}) +#define dbg_dump_znode(c, znode) ({}) +#define dbg_dump_heap(c, heap, cat) ({}) +#define dbg_dump_pnode(c, pnode, parent, iip) ({}) +#define dbg_dump_tnc(c) ({}) +#define dbg_dump_index(c) ({}) + +#define dbg_walk_index(c, leaf_cb, znode_cb, priv) 0 +#define dbg_old_index_check_init(c, zroot) 0 +#define dbg_check_old_index(c, zroot) 0 +#define dbg_check_cats(c) 0 +#define dbg_check_ltab(c) 0 +#define dbg_chk_lpt_free_spc(c) 0 +#define dbg_chk_lpt_sz(c, action, len) 0 +#define dbg_check_synced_i_size(inode) 0 +#define dbg_check_dir_size(c, dir) 0 +#define dbg_check_tnc(c, x) 0 +#define dbg_check_idx_size(c, idx_size) 0 +#define dbg_check_filesystem(c) 0 +#define dbg_check_heap(c, heap, cat, add_pos) ({}) +#define dbg_check_lprops(c) 0 +#define dbg_check_lpt_nodes(c, cnode, row, col) 0 +#define dbg_force_in_the_gaps_enabled 0 +#define dbg_force_in_the_gaps() 0 +#define dbg_failure_mode 0 +#define dbg_failure_mode_registration(c) ({}) +#define dbg_failure_mode_deregistration(c) ({}) + +int ubifs_debugging_init(struct ubifs_info *c); +void ubifs_debugging_exit(struct ubifs_info *c); + +#else /* !CONFIG_UBIFS_FS_DEBUG */ + +#define UBIFS_DBG(op) + +/* Use "if (0)" to make compiler check arguments even if debugging is off */ +#define ubifs_assert(expr) do { \ + if (0 && (expr)) \ + printk(KERN_CRIT "UBIFS assert failed in %s at %u (pid %d)\n", \ + __func__, __LINE__, 0); \ +} while (0) + +#define dbg_err(fmt, ...) do { \ + if (0) \ + ubifs_err(fmt, ##__VA_ARGS__); \ +} while (0) + +#define dbg_msg(fmt, ...) do { \ + if (0) \ + printk(KERN_DEBUG "UBIFS DBG (pid %d): %s: " fmt "\n", \ + 0, __func__, ##__VA_ARGS__); \ +} while (0) + +#define dbg_dump_stack() +#define ubifs_assert_cmt_locked(c) + +#define dbg_gen(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__) +#define dbg_jnl(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__) +#define dbg_tnc(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__) +#define dbg_lp(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__) +#define dbg_find(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__) +#define dbg_mnt(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__) +#define dbg_io(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__) +#define dbg_cmt(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__) +#define dbg_budg(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__) +#define dbg_log(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__) +#define dbg_gc(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__) +#define dbg_scan(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__) +#define dbg_rcvry(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__) + +#define DBGKEY(key) ((char *)(key)) +#define DBGKEY1(key) ((char *)(key)) + +#define ubifs_debugging_init(c) 0 +#define ubifs_debugging_exit(c) ({}) + +#define dbg_ntype(type) "" +#define dbg_cstate(cmt_state) "" +#define dbg_get_key_dump(c, key) ({}) +#define dbg_dump_inode(c, inode) ({}) +#define dbg_dump_node(c, node) ({}) +#define dbg_dump_budget_req(req) ({}) +#define dbg_dump_lstats(lst) ({}) +#define dbg_dump_budg(c) ({}) +#define dbg_dump_lprop(c, lp) ({}) +#define dbg_dump_lprops(c) ({}) +#define dbg_dump_lpt_info(c) ({}) +#define dbg_dump_leb(c, lnum) ({}) +#define dbg_dump_znode(c, znode) ({}) +#define dbg_dump_heap(c, heap, cat) ({}) +#define dbg_dump_pnode(c, pnode, parent, iip) ({}) +#define dbg_dump_tnc(c) ({}) +#define dbg_dump_index(c) ({}) + +#define dbg_walk_index(c, leaf_cb, znode_cb, priv) 0 +#define dbg_old_index_check_init(c, zroot) 0 +#define dbg_check_old_index(c, zroot) 0 +#define dbg_check_cats(c) 0 +#define dbg_check_ltab(c) 0 +#define dbg_chk_lpt_free_spc(c) 0 +#define dbg_chk_lpt_sz(c, action, len) 0 +#define dbg_check_synced_i_size(inode) 0 +#define dbg_check_dir_size(c, dir) 0 +#define dbg_check_tnc(c, x) 0 +#define dbg_check_idx_size(c, idx_size) 0 +#define dbg_check_filesystem(c) 0 +#define dbg_check_heap(c, heap, cat, add_pos) ({}) +#define dbg_check_lprops(c) 0 +#define dbg_check_lpt_nodes(c, cnode, row, col) 0 +#define dbg_force_in_the_gaps_enabled 0 +#define dbg_force_in_the_gaps() 0 +#define dbg_failure_mode 0 +#define dbg_failure_mode_registration(c) ({}) +#define dbg_failure_mode_deregistration(c) ({}) + +#endif /* !CONFIG_UBIFS_FS_DEBUG */ + +#endif /* !__UBIFS_DEBUG_H__ */ diff --git a/fs/ubifs/io.c b/fs/ubifs/io.c new file mode 100644 index 0000000..aae5c65 --- /dev/null +++ b/fs/ubifs/io.c @@ -0,0 +1,316 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * Copyright (C) 2006, 2007 University of Szeged, Hungary + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + * Zoltan Sogor + */ + +/* + * This file implements UBIFS I/O subsystem which provides various I/O-related + * helper functions (reading/writing/checking/validating nodes) and implements + * write-buffering support. Write buffers help to save space which otherwise + * would have been wasted for padding to the nearest minimal I/O unit boundary. + * Instead, data first goes to the write-buffer and is flushed when the + * buffer is full or when it is not used for some time (by timer). This is + * similar to the mechanism is used by JFFS2. + * + * Write-buffers are defined by 'struct ubifs_wbuf' objects and protected by + * mutexes defined inside these objects. Since sometimes upper-level code + * has to lock the write-buffer (e.g. journal space reservation code), many + * functions related to write-buffers have "nolock" suffix which means that the + * caller has to lock the write-buffer before calling this function. + * + * UBIFS stores nodes at 64 bit-aligned addresses. If the node length is not + * aligned, UBIFS starts the next node from the aligned address, and the padded + * bytes may contain any rubbish. In other words, UBIFS does not put padding + * bytes in those small gaps. Common headers of nodes store real node lengths, + * not aligned lengths. Indexing nodes also store real lengths in branches. + * + * UBIFS uses padding when it pads to the next min. I/O unit. In this case it + * uses padding nodes or padding bytes, if the padding node does not fit. + * + * All UBIFS nodes are protected by CRC checksums and UBIFS checks all nodes + * every time they are read from the flash media. + */ + +#include "ubifs.h" + +/** + * ubifs_ro_mode - switch UBIFS to read read-only mode. + * @c: UBIFS file-system description object + * @err: error code which is the reason of switching to R/O mode + */ +void ubifs_ro_mode(struct ubifs_info *c, int err) +{ + if (!c->ro_media) { + c->ro_media = 1; + c->no_chk_data_crc = 0; + ubifs_warn("switched to read-only mode, error %d", err); + dbg_dump_stack(); + } +} + +/** + * ubifs_check_node - check node. + * @c: UBIFS file-system description object + * @buf: node to check + * @lnum: logical eraseblock number + * @offs: offset within the logical eraseblock + * @quiet: print no messages + * @must_chk_crc: indicates whether to always check the CRC + * + * This function checks node magic number and CRC checksum. This function also + * validates node length to prevent UBIFS from becoming crazy when an attacker + * feeds it a file-system image with incorrect nodes. For example, too large + * node length in the common header could cause UBIFS to read memory outside of + * allocated buffer when checking the CRC checksum. + * + * This function may skip data nodes CRC checking if @c->no_chk_data_crc is + * true, which is controlled by corresponding UBIFS mount option. However, if + * @must_chk_crc is true, then @c->no_chk_data_crc is ignored and CRC is + * checked. Similarly, if @c->always_chk_crc is true, @c->no_chk_data_crc is + * ignored and CRC is checked. + * + * This function returns zero in case of success and %-EUCLEAN in case of bad + * CRC or magic. + */ +int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum, + int offs, int quiet, int must_chk_crc) +{ + int err = -EINVAL, type, node_len; + uint32_t crc, node_crc, magic; + const struct ubifs_ch *ch = buf; + + ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0); + ubifs_assert(!(offs & 7) && offs < c->leb_size); + + magic = le32_to_cpu(ch->magic); + if (magic != UBIFS_NODE_MAGIC) { + if (!quiet) + ubifs_err("bad magic %#08x, expected %#08x", + magic, UBIFS_NODE_MAGIC); + err = -EUCLEAN; + goto out; + } + + type = ch->node_type; + if (type < 0 || type >= UBIFS_NODE_TYPES_CNT) { + if (!quiet) + ubifs_err("bad node type %d", type); + goto out; + } + + node_len = le32_to_cpu(ch->len); + if (node_len + offs > c->leb_size) + goto out_len; + + if (c->ranges[type].max_len == 0) { + if (node_len != c->ranges[type].len) + goto out_len; + } else if (node_len < c->ranges[type].min_len || + node_len > c->ranges[type].max_len) + goto out_len; + + if (!must_chk_crc && type == UBIFS_DATA_NODE && !c->always_chk_crc && + c->no_chk_data_crc) + return 0; + + crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8); + node_crc = le32_to_cpu(ch->crc); + if (crc != node_crc) { + if (!quiet) + ubifs_err("bad CRC: calculated %#08x, read %#08x", + crc, node_crc); + err = -EUCLEAN; + goto out; + } + + return 0; + +out_len: + if (!quiet) + ubifs_err("bad node length %d", node_len); +out: + if (!quiet) { + ubifs_err("bad node at LEB %d:%d", lnum, offs); + dbg_dump_node(c, buf); + dbg_dump_stack(); + } + return err; +} + +/** + * ubifs_pad - pad flash space. + * @c: UBIFS file-system description object + * @buf: buffer to put padding to + * @pad: how many bytes to pad + * + * The flash media obliges us to write only in chunks of %c->min_io_size and + * when we have to write less data we add padding node to the write-buffer and + * pad it to the next minimal I/O unit's boundary. Padding nodes help when the + * media is being scanned. If the amount of wasted space is not enough to fit a + * padding node which takes %UBIFS_PAD_NODE_SZ bytes, we write padding bytes + * pattern (%UBIFS_PADDING_BYTE). + * + * Padding nodes are also used to fill gaps when the "commit-in-gaps" method is + * used. + */ +void ubifs_pad(const struct ubifs_info *c, void *buf, int pad) +{ + uint32_t crc; + + ubifs_assert(pad >= 0 && !(pad & 7)); + + if (pad >= UBIFS_PAD_NODE_SZ) { + struct ubifs_ch *ch = buf; + struct ubifs_pad_node *pad_node = buf; + + ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC); + ch->node_type = UBIFS_PAD_NODE; + ch->group_type = UBIFS_NO_NODE_GROUP; + ch->padding[0] = ch->padding[1] = 0; + ch->sqnum = 0; + ch->len = cpu_to_le32(UBIFS_PAD_NODE_SZ); + pad -= UBIFS_PAD_NODE_SZ; + pad_node->pad_len = cpu_to_le32(pad); + crc = crc32(UBIFS_CRC32_INIT, buf + 8, UBIFS_PAD_NODE_SZ - 8); + ch->crc = cpu_to_le32(crc); + memset(buf + UBIFS_PAD_NODE_SZ, 0, pad); + } else if (pad > 0) + /* Too little space, padding node won't fit */ + memset(buf, UBIFS_PADDING_BYTE, pad); +} + +/** + * next_sqnum - get next sequence number. + * @c: UBIFS file-system description object + */ +static unsigned long long next_sqnum(struct ubifs_info *c) +{ + unsigned long long sqnum; + + spin_lock(&c->cnt_lock); + sqnum = ++c->max_sqnum; + spin_unlock(&c->cnt_lock); + + if (unlikely(sqnum >= SQNUM_WARN_WATERMARK)) { + if (sqnum >= SQNUM_WATERMARK) { + ubifs_err("sequence number overflow %llu, end of life", + sqnum); + ubifs_ro_mode(c, -EINVAL); + } + ubifs_warn("running out of sequence numbers, end of life soon"); + } + + return sqnum; +} + +/** + * ubifs_prepare_node - prepare node to be written to flash. + * @c: UBIFS file-system description object + * @node: the node to pad + * @len: node length + * @pad: if the buffer has to be padded + * + * This function prepares node at @node to be written to the media - it + * calculates node CRC, fills the common header, and adds proper padding up to + * the next minimum I/O unit if @pad is not zero. + */ +void ubifs_prepare_node(struct ubifs_info *c, void *node, int len, int pad) +{ + uint32_t crc; + struct ubifs_ch *ch = node; + unsigned long long sqnum = next_sqnum(c); + + ubifs_assert(len >= UBIFS_CH_SZ); + + ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC); + ch->len = cpu_to_le32(len); + ch->group_type = UBIFS_NO_NODE_GROUP; + ch->sqnum = cpu_to_le64(sqnum); + ch->padding[0] = ch->padding[1] = 0; + crc = crc32(UBIFS_CRC32_INIT, node + 8, len - 8); + ch->crc = cpu_to_le32(crc); + + if (pad) { + len = ALIGN(len, 8); + pad = ALIGN(len, c->min_io_size) - len; + ubifs_pad(c, node + len, pad); + } +} + +/** + * ubifs_read_node - read node. + * @c: UBIFS file-system description object + * @buf: buffer to read to + * @type: node type + * @len: node length (not aligned) + * @lnum: logical eraseblock number + * @offs: offset within the logical eraseblock + * + * This function reads a node of known type and and length, checks it and + * stores in @buf. Returns zero in case of success, %-EUCLEAN if CRC mismatched + * and a negative error code in case of failure. + */ +int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len, + int lnum, int offs) +{ + int err, l; + struct ubifs_ch *ch = buf; + + dbg_io("LEB %d:%d, %s, length %d", lnum, offs, dbg_ntype(type), len); + ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0); + ubifs_assert(len >= UBIFS_CH_SZ && offs + len <= c->leb_size); + ubifs_assert(!(offs & 7) && offs < c->leb_size); + ubifs_assert(type >= 0 && type < UBIFS_NODE_TYPES_CNT); + + err = ubi_read(c->ubi, lnum, buf, offs, len); + if (err && err != -EBADMSG) { + ubifs_err("cannot read node %d from LEB %d:%d, error %d", + type, lnum, offs, err); + return err; + } + + if (type != ch->node_type) { + ubifs_err("bad node type (%d but expected %d)", + ch->node_type, type); + goto out; + } + + err = ubifs_check_node(c, buf, lnum, offs, 0, 0); + if (err) { + ubifs_err("expected node type %d", type); + return err; + } + + l = le32_to_cpu(ch->len); + if (l != len) { + ubifs_err("bad node length %d, expected %d", l, len); + goto out; + } + + return 0; + +out: + ubifs_err("bad node at LEB %d:%d", lnum, offs); + dbg_dump_node(c, buf); + dbg_dump_stack(); + return -EINVAL; +} diff --git a/fs/ubifs/key.h b/fs/ubifs/key.h new file mode 100644 index 0000000..efb3430 --- /dev/null +++ b/fs/ubifs/key.h @@ -0,0 +1,557 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This header contains various key-related definitions and helper function. + * UBIFS allows several key schemes, so we access key fields only via these + * helpers. At the moment only one key scheme is supported. + * + * Simple key scheme + * ~~~~~~~~~~~~~~~~~ + * + * Keys are 64-bits long. First 32-bits are inode number (parent inode number + * in case of direntry key). Next 3 bits are node type. The last 29 bits are + * 4KiB offset in case of inode node, and direntry hash in case of a direntry + * node. We use "r5" hash borrowed from reiserfs. + */ + +#ifndef __UBIFS_KEY_H__ +#define __UBIFS_KEY_H__ + +/** + * key_mask_hash - mask a valid hash value. + * @val: value to be masked + * + * We use hash values as offset in directories, so values %0 and %1 are + * reserved for "." and "..". %2 is reserved for "end of readdir" marker. This + * function makes sure the reserved values are not used. + */ +static inline uint32_t key_mask_hash(uint32_t hash) +{ + hash &= UBIFS_S_KEY_HASH_MASK; + if (unlikely(hash <= 2)) + hash += 3; + return hash; +} + +/** + * key_r5_hash - R5 hash function (borrowed from reiserfs). + * @s: direntry name + * @len: name length + */ +static inline uint32_t key_r5_hash(const char *s, int len) +{ + uint32_t a = 0; + const signed char *str = (const signed char *)s; + + while (*str) { + a += *str << 4; + a += *str >> 4; + a *= 11; + str++; + } + + return key_mask_hash(a); +} + +/** + * key_test_hash - testing hash function. + * @str: direntry name + * @len: name length + */ +static inline uint32_t key_test_hash(const char *str, int len) +{ + uint32_t a = 0; + + len = min_t(uint32_t, len, 4); + memcpy(&a, str, len); + return key_mask_hash(a); +} + +/** + * ino_key_init - initialize inode key. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: inode number + */ +static inline void ino_key_init(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum) +{ + key->u32[0] = inum; + key->u32[1] = UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS; +} + +/** + * ino_key_init_flash - initialize on-flash inode key. + * @c: UBIFS file-system description object + * @k: key to initialize + * @inum: inode number + */ +static inline void ino_key_init_flash(const struct ubifs_info *c, void *k, + ino_t inum) +{ + union ubifs_key *key = k; + + key->j32[0] = cpu_to_le32(inum); + key->j32[1] = cpu_to_le32(UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS); + memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8); +} + +/** + * lowest_ino_key - get the lowest possible inode key. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: inode number + */ +static inline void lowest_ino_key(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum) +{ + key->u32[0] = inum; + key->u32[1] = 0; +} + +/** + * highest_ino_key - get the highest possible inode key. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: inode number + */ +static inline void highest_ino_key(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum) +{ + key->u32[0] = inum; + key->u32[1] = 0xffffffff; +} + +/** + * dent_key_init - initialize directory entry key. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: parent inode number + * @nm: direntry name and length + */ +static inline void dent_key_init(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum, + const struct qstr *nm) +{ + uint32_t hash = c->key_hash(nm->name, nm->len); + + ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK)); + key->u32[0] = inum; + key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS); +} + +/** + * dent_key_init_hash - initialize directory entry key without re-calculating + * hash function. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: parent inode number + * @hash: direntry name hash + */ +static inline void dent_key_init_hash(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum, + uint32_t hash) +{ + ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK)); + key->u32[0] = inum; + key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS); +} + +/** + * dent_key_init_flash - initialize on-flash directory entry key. + * @c: UBIFS file-system description object + * @k: key to initialize + * @inum: parent inode number + * @nm: direntry name and length + */ +static inline void dent_key_init_flash(const struct ubifs_info *c, void *k, + ino_t inum, const struct qstr *nm) +{ + union ubifs_key *key = k; + uint32_t hash = c->key_hash(nm->name, nm->len); + + ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK)); + key->j32[0] = cpu_to_le32(inum); + key->j32[1] = cpu_to_le32(hash | + (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS)); + memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8); +} + +/** + * lowest_dent_key - get the lowest possible directory entry key. + * @c: UBIFS file-system description object + * @key: where to store the lowest key + * @inum: parent inode number + */ +static inline void lowest_dent_key(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum) +{ + key->u32[0] = inum; + key->u32[1] = UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS; +} + +/** + * xent_key_init - initialize extended attribute entry key. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: host inode number + * @nm: extended attribute entry name and length + */ +static inline void xent_key_init(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum, + const struct qstr *nm) +{ + uint32_t hash = c->key_hash(nm->name, nm->len); + + ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK)); + key->u32[0] = inum; + key->u32[1] = hash | (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS); +} + +/** + * xent_key_init_hash - initialize extended attribute entry key without + * re-calculating hash function. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: host inode number + * @hash: extended attribute entry name hash + */ +static inline void xent_key_init_hash(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum, + uint32_t hash) +{ + ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK)); + key->u32[0] = inum; + key->u32[1] = hash | (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS); +} + +/** + * xent_key_init_flash - initialize on-flash extended attribute entry key. + * @c: UBIFS file-system description object + * @k: key to initialize + * @inum: host inode number + * @nm: extended attribute entry name and length + */ +static inline void xent_key_init_flash(const struct ubifs_info *c, void *k, + ino_t inum, const struct qstr *nm) +{ + union ubifs_key *key = k; + uint32_t hash = c->key_hash(nm->name, nm->len); + + ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK)); + key->j32[0] = cpu_to_le32(inum); + key->j32[1] = cpu_to_le32(hash | + (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS)); + memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8); +} + +/** + * lowest_xent_key - get the lowest possible extended attribute entry key. + * @c: UBIFS file-system description object + * @key: where to store the lowest key + * @inum: host inode number + */ +static inline void lowest_xent_key(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum) +{ + key->u32[0] = inum; + key->u32[1] = UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS; +} + +/** + * data_key_init - initialize data key. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: inode number + * @block: block number + */ +static inline void data_key_init(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum, + unsigned int block) +{ + ubifs_assert(!(block & ~UBIFS_S_KEY_BLOCK_MASK)); + key->u32[0] = inum; + key->u32[1] = block | (UBIFS_DATA_KEY << UBIFS_S_KEY_BLOCK_BITS); +} + +/** + * data_key_init_flash - initialize on-flash data key. + * @c: UBIFS file-system description object + * @k: key to initialize + * @inum: inode number + * @block: block number + */ +static inline void data_key_init_flash(const struct ubifs_info *c, void *k, + ino_t inum, unsigned int block) +{ + union ubifs_key *key = k; + + ubifs_assert(!(block & ~UBIFS_S_KEY_BLOCK_MASK)); + key->j32[0] = cpu_to_le32(inum); + key->j32[1] = cpu_to_le32(block | + (UBIFS_DATA_KEY << UBIFS_S_KEY_BLOCK_BITS)); + memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8); +} + +/** + * trun_key_init - initialize truncation node key. + * @c: UBIFS file-system description object + * @key: key to initialize + * @inum: inode number + * + * Note, UBIFS does not have truncation keys on the media and this function is + * only used for purposes of replay. + */ +static inline void trun_key_init(const struct ubifs_info *c, + union ubifs_key *key, ino_t inum) +{ + key->u32[0] = inum; + key->u32[1] = UBIFS_TRUN_KEY << UBIFS_S_KEY_BLOCK_BITS; +} + +/** + * key_type - get key type. + * @c: UBIFS file-system description object + * @key: key to get type of + */ +static inline int key_type(const struct ubifs_info *c, + const union ubifs_key *key) +{ + return key->u32[1] >> UBIFS_S_KEY_BLOCK_BITS; +} + +/** + * key_type_flash - get type of a on-flash formatted key. + * @c: UBIFS file-system description object + * @k: key to get type of + */ +static inline int key_type_flash(const struct ubifs_info *c, const void *k) +{ + const union ubifs_key *key = k; + + return le32_to_cpu(key->j32[1]) >> UBIFS_S_KEY_BLOCK_BITS; +} + +/** + * key_inum - fetch inode number from key. + * @c: UBIFS file-system description object + * @k: key to fetch inode number from + */ +static inline ino_t key_inum(const struct ubifs_info *c, const void *k) +{ + const union ubifs_key *key = k; + + return key->u32[0]; +} + +/** + * key_inum_flash - fetch inode number from an on-flash formatted key. + * @c: UBIFS file-system description object + * @k: key to fetch inode number from + */ +static inline ino_t key_inum_flash(const struct ubifs_info *c, const void *k) +{ + const union ubifs_key *key = k; + + return le32_to_cpu(key->j32[0]); +} + +/** + * key_hash - get directory entry hash. + * @c: UBIFS file-system description object + * @key: the key to get hash from + */ +static inline int key_hash(const struct ubifs_info *c, + const union ubifs_key *key) +{ + return key->u32[1] & UBIFS_S_KEY_HASH_MASK; +} + +/** + * key_hash_flash - get directory entry hash from an on-flash formatted key. + * @c: UBIFS file-system description object + * @k: the key to get hash from + */ +static inline int key_hash_flash(const struct ubifs_info *c, const void *k) +{ + const union ubifs_key *key = k; + + return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_HASH_MASK; +} + +/** + * key_block - get data block number. + * @c: UBIFS file-system description object + * @key: the key to get the block number from + */ +static inline unsigned int key_block(const struct ubifs_info *c, + const union ubifs_key *key) +{ + return key->u32[1] & UBIFS_S_KEY_BLOCK_MASK; +} + +/** + * key_block_flash - get data block number from an on-flash formatted key. + * @c: UBIFS file-system description object + * @k: the key to get the block number from + */ +static inline unsigned int key_block_flash(const struct ubifs_info *c, + const void *k) +{ + const union ubifs_key *key = k; + + return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_BLOCK_MASK; +} + +/** + * key_read - transform a key to in-memory format. + * @c: UBIFS file-system description object + * @from: the key to transform + * @to: the key to store the result + */ +static inline void key_read(const struct ubifs_info *c, const void *from, + union ubifs_key *to) +{ + const union ubifs_key *f = from; + + to->u32[0] = le32_to_cpu(f->j32[0]); + to->u32[1] = le32_to_cpu(f->j32[1]); +} + +/** + * key_write - transform a key from in-memory format. + * @c: UBIFS file-system description object + * @from: the key to transform + * @to: the key to store the result + */ +static inline void key_write(const struct ubifs_info *c, + const union ubifs_key *from, void *to) +{ + union ubifs_key *t = to; + + t->j32[0] = cpu_to_le32(from->u32[0]); + t->j32[1] = cpu_to_le32(from->u32[1]); + memset(to + 8, 0, UBIFS_MAX_KEY_LEN - 8); +} + +/** + * key_write_idx - transform a key from in-memory format for the index. + * @c: UBIFS file-system description object + * @from: the key to transform + * @to: the key to store the result + */ +static inline void key_write_idx(const struct ubifs_info *c, + const union ubifs_key *from, void *to) +{ + union ubifs_key *t = to; + + t->j32[0] = cpu_to_le32(from->u32[0]); + t->j32[1] = cpu_to_le32(from->u32[1]); +} + +/** + * key_copy - copy a key. + * @c: UBIFS file-system description object + * @from: the key to copy from + * @to: the key to copy to + */ +static inline void key_copy(const struct ubifs_info *c, + const union ubifs_key *from, union ubifs_key *to) +{ + to->u64[0] = from->u64[0]; +} + +/** + * keys_cmp - compare keys. + * @c: UBIFS file-system description object + * @key1: the first key to compare + * @key2: the second key to compare + * + * This function compares 2 keys and returns %-1 if @key1 is less than + * @key2, %0 if the keys are equivalent and %1 if @key1 is greater than @key2. + */ +static inline int keys_cmp(const struct ubifs_info *c, + const union ubifs_key *key1, + const union ubifs_key *key2) +{ + if (key1->u32[0] < key2->u32[0]) + return -1; + if (key1->u32[0] > key2->u32[0]) + return 1; + if (key1->u32[1] < key2->u32[1]) + return -1; + if (key1->u32[1] > key2->u32[1]) + return 1; + + return 0; +} + +/** + * keys_eq - determine if keys are equivalent. + * @c: UBIFS file-system description object + * @key1: the first key to compare + * @key2: the second key to compare + * + * This function compares 2 keys and returns %1 if @key1 is equal to @key2 and + * %0 if not. + */ +static inline int keys_eq(const struct ubifs_info *c, + const union ubifs_key *key1, + const union ubifs_key *key2) +{ + if (key1->u32[0] != key2->u32[0]) + return 0; + if (key1->u32[1] != key2->u32[1]) + return 0; + return 1; +} + +/** + * is_hash_key - is a key vulnerable to hash collisions. + * @c: UBIFS file-system description object + * @key: key + * + * This function returns %1 if @key is a hashed key or %0 otherwise. + */ +static inline int is_hash_key(const struct ubifs_info *c, + const union ubifs_key *key) +{ + int type = key_type(c, key); + + return type == UBIFS_DENT_KEY || type == UBIFS_XENT_KEY; +} + +/** + * key_max_inode_size - get maximum file size allowed by current key format. + * @c: UBIFS file-system description object + */ +static inline unsigned long long key_max_inode_size(const struct ubifs_info *c) +{ + switch (c->key_fmt) { + case UBIFS_SIMPLE_KEY_FMT: + return (1ULL << UBIFS_S_KEY_BLOCK_BITS) * UBIFS_BLOCK_SIZE; + default: + return 0; + } +} +#endif /* !__UBIFS_KEY_H__ */ diff --git a/fs/ubifs/log.c b/fs/ubifs/log.c new file mode 100644 index 0000000..68a9bd9 --- /dev/null +++ b/fs/ubifs/log.c @@ -0,0 +1,104 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file is a part of UBIFS journal implementation and contains various + * functions which manipulate the log. The log is a fixed area on the flash + * which does not contain any data but refers to buds. The log is a part of the + * journal. + */ + +#include "ubifs.h" + +/** + * ubifs_search_bud - search bud LEB. + * @c: UBIFS file-system description object + * @lnum: logical eraseblock number to search + * + * This function searches bud LEB @lnum. Returns bud description object in case + * of success and %NULL if there is no bud with this LEB number. + */ +struct ubifs_bud *ubifs_search_bud(struct ubifs_info *c, int lnum) +{ + struct rb_node *p; + struct ubifs_bud *bud; + + spin_lock(&c->buds_lock); + p = c->buds.rb_node; + while (p) { + bud = rb_entry(p, struct ubifs_bud, rb); + if (lnum < bud->lnum) + p = p->rb_left; + else if (lnum > bud->lnum) + p = p->rb_right; + else { + spin_unlock(&c->buds_lock); + return bud; + } + } + spin_unlock(&c->buds_lock); + return NULL; +} + +/** + * ubifs_add_bud - add bud LEB to the tree of buds and its journal head list. + * @c: UBIFS file-system description object + * @bud: the bud to add + */ +void ubifs_add_bud(struct ubifs_info *c, struct ubifs_bud *bud) +{ + struct rb_node **p, *parent = NULL; + struct ubifs_bud *b; + struct ubifs_jhead *jhead; + + spin_lock(&c->buds_lock); + p = &c->buds.rb_node; + while (*p) { + parent = *p; + b = rb_entry(parent, struct ubifs_bud, rb); + ubifs_assert(bud->lnum != b->lnum); + if (bud->lnum < b->lnum) + p = &(*p)->rb_left; + else + p = &(*p)->rb_right; + } + + rb_link_node(&bud->rb, parent, p); + rb_insert_color(&bud->rb, &c->buds); + if (c->jheads) { + jhead = &c->jheads[bud->jhead]; + list_add_tail(&bud->list, &jhead->buds_list); + } else + ubifs_assert(c->replaying && (c->vfs_sb->s_flags & MS_RDONLY)); + + /* + * Note, although this is a new bud, we anyway account this space now, + * before any data has been written to it, because this is about to + * guarantee fixed mount time, and this bud will anyway be read and + * scanned. + */ + c->bud_bytes += c->leb_size - bud->start; + + dbg_log("LEB %d:%d, jhead %d, bud_bytes %lld", bud->lnum, + bud->start, bud->jhead, c->bud_bytes); + spin_unlock(&c->buds_lock); +} diff --git a/fs/ubifs/lprops.c b/fs/ubifs/lprops.c new file mode 100644 index 0000000..8ce4949 --- /dev/null +++ b/fs/ubifs/lprops.c @@ -0,0 +1,842 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements the functions that access LEB properties and their + * categories. LEBs are categorized based on the needs of UBIFS, and the + * categories are stored as either heaps or lists to provide a fast way of + * finding a LEB in a particular category. For example, UBIFS may need to find + * an empty LEB for the journal, or a very dirty LEB for garbage collection. + */ + +#include "ubifs.h" + +/** + * get_heap_comp_val - get the LEB properties value for heap comparisons. + * @lprops: LEB properties + * @cat: LEB category + */ +static int get_heap_comp_val(struct ubifs_lprops *lprops, int cat) +{ + switch (cat) { + case LPROPS_FREE: + return lprops->free; + case LPROPS_DIRTY_IDX: + return lprops->free + lprops->dirty; + default: + return lprops->dirty; + } +} + +/** + * move_up_lpt_heap - move a new heap entry up as far as possible. + * @c: UBIFS file-system description object + * @heap: LEB category heap + * @lprops: LEB properties to move + * @cat: LEB category + * + * New entries to a heap are added at the bottom and then moved up until the + * parent's value is greater. In the case of LPT's category heaps, the value + * is either the amount of free space or the amount of dirty space, depending + * on the category. + */ +static void move_up_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, + struct ubifs_lprops *lprops, int cat) +{ + int val1, val2, hpos; + + hpos = lprops->hpos; + if (!hpos) + return; /* Already top of the heap */ + val1 = get_heap_comp_val(lprops, cat); + /* Compare to parent and, if greater, move up the heap */ + do { + int ppos = (hpos - 1) / 2; + + val2 = get_heap_comp_val(heap->arr[ppos], cat); + if (val2 >= val1) + return; + /* Greater than parent so move up */ + heap->arr[ppos]->hpos = hpos; + heap->arr[hpos] = heap->arr[ppos]; + heap->arr[ppos] = lprops; + lprops->hpos = ppos; + hpos = ppos; + } while (hpos); +} + +/** + * adjust_lpt_heap - move a changed heap entry up or down the heap. + * @c: UBIFS file-system description object + * @heap: LEB category heap + * @lprops: LEB properties to move + * @hpos: heap position of @lprops + * @cat: LEB category + * + * Changed entries in a heap are moved up or down until the parent's value is + * greater. In the case of LPT's category heaps, the value is either the amount + * of free space or the amount of dirty space, depending on the category. + */ +static void adjust_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, + struct ubifs_lprops *lprops, int hpos, int cat) +{ + int val1, val2, val3, cpos; + + val1 = get_heap_comp_val(lprops, cat); + /* Compare to parent and, if greater than parent, move up the heap */ + if (hpos) { + int ppos = (hpos - 1) / 2; + + val2 = get_heap_comp_val(heap->arr[ppos], cat); + if (val1 > val2) { + /* Greater than parent so move up */ + while (1) { + heap->arr[ppos]->hpos = hpos; + heap->arr[hpos] = heap->arr[ppos]; + heap->arr[ppos] = lprops; + lprops->hpos = ppos; + hpos = ppos; + if (!hpos) + return; + ppos = (hpos - 1) / 2; + val2 = get_heap_comp_val(heap->arr[ppos], cat); + if (val1 <= val2) + return; + /* Still greater than parent so keep going */ + } + } + } + + /* Not greater than parent, so compare to children */ + while (1) { + /* Compare to left child */ + cpos = hpos * 2 + 1; + if (cpos >= heap->cnt) + return; + val2 = get_heap_comp_val(heap->arr[cpos], cat); + if (val1 < val2) { + /* Less than left child, so promote biggest child */ + if (cpos + 1 < heap->cnt) { + val3 = get_heap_comp_val(heap->arr[cpos + 1], + cat); + if (val3 > val2) + cpos += 1; /* Right child is bigger */ + } + heap->arr[cpos]->hpos = hpos; + heap->arr[hpos] = heap->arr[cpos]; + heap->arr[cpos] = lprops; + lprops->hpos = cpos; + hpos = cpos; + continue; + } + /* Compare to right child */ + cpos += 1; + if (cpos >= heap->cnt) + return; + val3 = get_heap_comp_val(heap->arr[cpos], cat); + if (val1 < val3) { + /* Less than right child, so promote right child */ + heap->arr[cpos]->hpos = hpos; + heap->arr[hpos] = heap->arr[cpos]; + heap->arr[cpos] = lprops; + lprops->hpos = cpos; + hpos = cpos; + continue; + } + return; + } +} + +/** + * add_to_lpt_heap - add LEB properties to a LEB category heap. + * @c: UBIFS file-system description object + * @lprops: LEB properties to add + * @cat: LEB category + * + * This function returns %1 if @lprops is added to the heap for LEB category + * @cat, otherwise %0 is returned because the heap is full. + */ +static int add_to_lpt_heap(struct ubifs_info *c, struct ubifs_lprops *lprops, + int cat) +{ + struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1]; + + if (heap->cnt >= heap->max_cnt) { + const int b = LPT_HEAP_SZ / 2 - 1; + int cpos, val1, val2; + + /* Compare to some other LEB on the bottom of heap */ + /* Pick a position kind of randomly */ + cpos = (((size_t)lprops >> 4) & b) + b; + ubifs_assert(cpos >= b); + ubifs_assert(cpos < LPT_HEAP_SZ); + ubifs_assert(cpos < heap->cnt); + + val1 = get_heap_comp_val(lprops, cat); + val2 = get_heap_comp_val(heap->arr[cpos], cat); + if (val1 > val2) { + struct ubifs_lprops *lp; + + lp = heap->arr[cpos]; + lp->flags &= ~LPROPS_CAT_MASK; + lp->flags |= LPROPS_UNCAT; + list_add(&lp->list, &c->uncat_list); + lprops->hpos = cpos; + heap->arr[cpos] = lprops; + move_up_lpt_heap(c, heap, lprops, cat); + dbg_check_heap(c, heap, cat, lprops->hpos); + return 1; /* Added to heap */ + } + dbg_check_heap(c, heap, cat, -1); + return 0; /* Not added to heap */ + } else { + lprops->hpos = heap->cnt++; + heap->arr[lprops->hpos] = lprops; + move_up_lpt_heap(c, heap, lprops, cat); + dbg_check_heap(c, heap, cat, lprops->hpos); + return 1; /* Added to heap */ + } +} + +/** + * remove_from_lpt_heap - remove LEB properties from a LEB category heap. + * @c: UBIFS file-system description object + * @lprops: LEB properties to remove + * @cat: LEB category + */ +static void remove_from_lpt_heap(struct ubifs_info *c, + struct ubifs_lprops *lprops, int cat) +{ + struct ubifs_lpt_heap *heap; + int hpos = lprops->hpos; + + heap = &c->lpt_heap[cat - 1]; + ubifs_assert(hpos >= 0 && hpos < heap->cnt); + ubifs_assert(heap->arr[hpos] == lprops); + heap->cnt -= 1; + if (hpos < heap->cnt) { + heap->arr[hpos] = heap->arr[heap->cnt]; + heap->arr[hpos]->hpos = hpos; + adjust_lpt_heap(c, heap, heap->arr[hpos], hpos, cat); + } + dbg_check_heap(c, heap, cat, -1); +} + +/** + * lpt_heap_replace - replace lprops in a category heap. + * @c: UBIFS file-system description object + * @old_lprops: LEB properties to replace + * @new_lprops: LEB properties with which to replace + * @cat: LEB category + * + * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode) + * and the lprops that the pnode contains. When that happens, references in + * the category heaps to those lprops must be updated to point to the new + * lprops. This function does that. + */ +static void lpt_heap_replace(struct ubifs_info *c, + struct ubifs_lprops *old_lprops, + struct ubifs_lprops *new_lprops, int cat) +{ + struct ubifs_lpt_heap *heap; + int hpos = new_lprops->hpos; + + heap = &c->lpt_heap[cat - 1]; + heap->arr[hpos] = new_lprops; +} + +/** + * ubifs_add_to_cat - add LEB properties to a category list or heap. + * @c: UBIFS file-system description object + * @lprops: LEB properties to add + * @cat: LEB category to which to add + * + * LEB properties are categorized to enable fast find operations. + */ +void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops, + int cat) +{ + switch (cat) { + case LPROPS_DIRTY: + case LPROPS_DIRTY_IDX: + case LPROPS_FREE: + if (add_to_lpt_heap(c, lprops, cat)) + break; + /* No more room on heap so make it uncategorized */ + cat = LPROPS_UNCAT; + /* Fall through */ + case LPROPS_UNCAT: + list_add(&lprops->list, &c->uncat_list); + break; + case LPROPS_EMPTY: + list_add(&lprops->list, &c->empty_list); + break; + case LPROPS_FREEABLE: + list_add(&lprops->list, &c->freeable_list); + c->freeable_cnt += 1; + break; + case LPROPS_FRDI_IDX: + list_add(&lprops->list, &c->frdi_idx_list); + break; + default: + ubifs_assert(0); + } + lprops->flags &= ~LPROPS_CAT_MASK; + lprops->flags |= cat; +} + +/** + * ubifs_remove_from_cat - remove LEB properties from a category list or heap. + * @c: UBIFS file-system description object + * @lprops: LEB properties to remove + * @cat: LEB category from which to remove + * + * LEB properties are categorized to enable fast find operations. + */ +static void ubifs_remove_from_cat(struct ubifs_info *c, + struct ubifs_lprops *lprops, int cat) +{ + switch (cat) { + case LPROPS_DIRTY: + case LPROPS_DIRTY_IDX: + case LPROPS_FREE: + remove_from_lpt_heap(c, lprops, cat); + break; + case LPROPS_FREEABLE: + c->freeable_cnt -= 1; + ubifs_assert(c->freeable_cnt >= 0); + /* Fall through */ + case LPROPS_UNCAT: + case LPROPS_EMPTY: + case LPROPS_FRDI_IDX: + ubifs_assert(!list_empty(&lprops->list)); + list_del(&lprops->list); + break; + default: + ubifs_assert(0); + } +} + +/** + * ubifs_replace_cat - replace lprops in a category list or heap. + * @c: UBIFS file-system description object + * @old_lprops: LEB properties to replace + * @new_lprops: LEB properties with which to replace + * + * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode) + * and the lprops that the pnode contains. When that happens, references in + * category lists and heaps must be replaced. This function does that. + */ +void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops, + struct ubifs_lprops *new_lprops) +{ + int cat; + + cat = new_lprops->flags & LPROPS_CAT_MASK; + switch (cat) { + case LPROPS_DIRTY: + case LPROPS_DIRTY_IDX: + case LPROPS_FREE: + lpt_heap_replace(c, old_lprops, new_lprops, cat); + break; + case LPROPS_UNCAT: + case LPROPS_EMPTY: + case LPROPS_FREEABLE: + case LPROPS_FRDI_IDX: + list_replace(&old_lprops->list, &new_lprops->list); + break; + default: + ubifs_assert(0); + } +} + +/** + * ubifs_ensure_cat - ensure LEB properties are categorized. + * @c: UBIFS file-system description object + * @lprops: LEB properties + * + * A LEB may have fallen off of the bottom of a heap, and ended up as + * uncategorized even though it has enough space for us now. If that is the case + * this function will put the LEB back onto a heap. + */ +void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops) +{ + int cat = lprops->flags & LPROPS_CAT_MASK; + + if (cat != LPROPS_UNCAT) + return; + cat = ubifs_categorize_lprops(c, lprops); + if (cat == LPROPS_UNCAT) + return; + ubifs_remove_from_cat(c, lprops, LPROPS_UNCAT); + ubifs_add_to_cat(c, lprops, cat); +} + +/** + * ubifs_categorize_lprops - categorize LEB properties. + * @c: UBIFS file-system description object + * @lprops: LEB properties to categorize + * + * LEB properties are categorized to enable fast find operations. This function + * returns the LEB category to which the LEB properties belong. Note however + * that if the LEB category is stored as a heap and the heap is full, the + * LEB properties may have their category changed to %LPROPS_UNCAT. + */ +int ubifs_categorize_lprops(const struct ubifs_info *c, + const struct ubifs_lprops *lprops) +{ + if (lprops->flags & LPROPS_TAKEN) + return LPROPS_UNCAT; + + if (lprops->free == c->leb_size) { + ubifs_assert(!(lprops->flags & LPROPS_INDEX)); + return LPROPS_EMPTY; + } + + if (lprops->free + lprops->dirty == c->leb_size) { + if (lprops->flags & LPROPS_INDEX) + return LPROPS_FRDI_IDX; + else + return LPROPS_FREEABLE; + } + + if (lprops->flags & LPROPS_INDEX) { + if (lprops->dirty + lprops->free >= c->min_idx_node_sz) + return LPROPS_DIRTY_IDX; + } else { + if (lprops->dirty >= c->dead_wm && + lprops->dirty > lprops->free) + return LPROPS_DIRTY; + if (lprops->free > 0) + return LPROPS_FREE; + } + + return LPROPS_UNCAT; +} + +/** + * change_category - change LEB properties category. + * @c: UBIFS file-system description object + * @lprops: LEB properties to recategorize + * + * LEB properties are categorized to enable fast find operations. When the LEB + * properties change they must be recategorized. + */ +static void change_category(struct ubifs_info *c, struct ubifs_lprops *lprops) +{ + int old_cat = lprops->flags & LPROPS_CAT_MASK; + int new_cat = ubifs_categorize_lprops(c, lprops); + + if (old_cat == new_cat) { + struct ubifs_lpt_heap *heap = &c->lpt_heap[new_cat - 1]; + + /* lprops on a heap now must be moved up or down */ + if (new_cat < 1 || new_cat > LPROPS_HEAP_CNT) + return; /* Not on a heap */ + heap = &c->lpt_heap[new_cat - 1]; + adjust_lpt_heap(c, heap, lprops, lprops->hpos, new_cat); + } else { + ubifs_remove_from_cat(c, lprops, old_cat); + ubifs_add_to_cat(c, lprops, new_cat); + } +} + +/** + * calc_dark - calculate LEB dark space size. + * @c: the UBIFS file-system description object + * @spc: amount of free and dirty space in the LEB + * + * This function calculates amount of dark space in an LEB which has @spc bytes + * of free and dirty space. Returns the calculations result. + * + * Dark space is the space which is not always usable - it depends on which + * nodes are written in which order. E.g., if an LEB has only 512 free bytes, + * it is dark space, because it cannot fit a large data node. So UBIFS cannot + * count on this LEB and treat these 512 bytes as usable because it is not true + * if, for example, only big chunks of uncompressible data will be written to + * the FS. + */ +static int calc_dark(struct ubifs_info *c, int spc) +{ + ubifs_assert(!(spc & 7)); + + if (spc < c->dark_wm) + return spc; + + /* + * If we have slightly more space then the dark space watermark, we can + * anyway safely assume it we'll be able to write a node of the + * smallest size there. + */ + if (spc - c->dark_wm < MIN_WRITE_SZ) + return spc - MIN_WRITE_SZ; + + return c->dark_wm; +} + +/** + * is_lprops_dirty - determine if LEB properties are dirty. + * @c: the UBIFS file-system description object + * @lprops: LEB properties to test + */ +static int is_lprops_dirty(struct ubifs_info *c, struct ubifs_lprops *lprops) +{ + struct ubifs_pnode *pnode; + int pos; + + pos = (lprops->lnum - c->main_first) & (UBIFS_LPT_FANOUT - 1); + pnode = (struct ubifs_pnode *)container_of(lprops - pos, + struct ubifs_pnode, + lprops[0]); + return !test_bit(COW_ZNODE, &pnode->flags) && + test_bit(DIRTY_CNODE, &pnode->flags); +} + +/** + * ubifs_change_lp - change LEB properties. + * @c: the UBIFS file-system description object + * @lp: LEB properties to change + * @free: new free space amount + * @dirty: new dirty space amount + * @flags: new flags + * @idx_gc_cnt: change to the count of idx_gc list + * + * This function changes LEB properties (@free, @dirty or @flag). However, the + * property which has the %LPROPS_NC value is not changed. Returns a pointer to + * the updated LEB properties on success and a negative error code on failure. + * + * Note, the LEB properties may have had to be copied (due to COW) and + * consequently the pointer returned may not be the same as the pointer + * passed. + */ +const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c, + const struct ubifs_lprops *lp, + int free, int dirty, int flags, + int idx_gc_cnt) +{ + /* + * This is the only function that is allowed to change lprops, so we + * discard the const qualifier. + */ + struct ubifs_lprops *lprops = (struct ubifs_lprops *)lp; + + dbg_lp("LEB %d, free %d, dirty %d, flags %d", + lprops->lnum, free, dirty, flags); + + ubifs_assert(mutex_is_locked(&c->lp_mutex)); + ubifs_assert(c->lst.empty_lebs >= 0 && + c->lst.empty_lebs <= c->main_lebs); + ubifs_assert(c->freeable_cnt >= 0); + ubifs_assert(c->freeable_cnt <= c->main_lebs); + ubifs_assert(c->lst.taken_empty_lebs >= 0); + ubifs_assert(c->lst.taken_empty_lebs <= c->lst.empty_lebs); + ubifs_assert(!(c->lst.total_free & 7) && !(c->lst.total_dirty & 7)); + ubifs_assert(!(c->lst.total_dead & 7) && !(c->lst.total_dark & 7)); + ubifs_assert(!(c->lst.total_used & 7)); + ubifs_assert(free == LPROPS_NC || free >= 0); + ubifs_assert(dirty == LPROPS_NC || dirty >= 0); + + if (!is_lprops_dirty(c, lprops)) { + lprops = ubifs_lpt_lookup_dirty(c, lprops->lnum); + if (IS_ERR(lprops)) + return lprops; + } else + ubifs_assert(lprops == ubifs_lpt_lookup_dirty(c, lprops->lnum)); + + ubifs_assert(!(lprops->free & 7) && !(lprops->dirty & 7)); + + spin_lock(&c->space_lock); + if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size) + c->lst.taken_empty_lebs -= 1; + + if (!(lprops->flags & LPROPS_INDEX)) { + int old_spc; + + old_spc = lprops->free + lprops->dirty; + if (old_spc < c->dead_wm) + c->lst.total_dead -= old_spc; + else + c->lst.total_dark -= calc_dark(c, old_spc); + + c->lst.total_used -= c->leb_size - old_spc; + } + + if (free != LPROPS_NC) { + free = ALIGN(free, 8); + c->lst.total_free += free - lprops->free; + + /* Increase or decrease empty LEBs counter if needed */ + if (free == c->leb_size) { + if (lprops->free != c->leb_size) + c->lst.empty_lebs += 1; + } else if (lprops->free == c->leb_size) + c->lst.empty_lebs -= 1; + lprops->free = free; + } + + if (dirty != LPROPS_NC) { + dirty = ALIGN(dirty, 8); + c->lst.total_dirty += dirty - lprops->dirty; + lprops->dirty = dirty; + } + + if (flags != LPROPS_NC) { + /* Take care about indexing LEBs counter if needed */ + if ((lprops->flags & LPROPS_INDEX)) { + if (!(flags & LPROPS_INDEX)) + c->lst.idx_lebs -= 1; + } else if (flags & LPROPS_INDEX) + c->lst.idx_lebs += 1; + lprops->flags = flags; + } + + if (!(lprops->flags & LPROPS_INDEX)) { + int new_spc; + + new_spc = lprops->free + lprops->dirty; + if (new_spc < c->dead_wm) + c->lst.total_dead += new_spc; + else + c->lst.total_dark += calc_dark(c, new_spc); + + c->lst.total_used += c->leb_size - new_spc; + } + + if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size) + c->lst.taken_empty_lebs += 1; + + change_category(c, lprops); + c->idx_gc_cnt += idx_gc_cnt; + spin_unlock(&c->space_lock); + return lprops; +} + +/** + * ubifs_get_lp_stats - get lprops statistics. + * @c: UBIFS file-system description object + * @st: return statistics + */ +void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst) +{ + spin_lock(&c->space_lock); + memcpy(lst, &c->lst, sizeof(struct ubifs_lp_stats)); + spin_unlock(&c->space_lock); +} + +/** + * ubifs_change_one_lp - change LEB properties. + * @c: the UBIFS file-system description object + * @lnum: LEB to change properties for + * @free: amount of free space + * @dirty: amount of dirty space + * @flags_set: flags to set + * @flags_clean: flags to clean + * @idx_gc_cnt: change to the count of idx_gc list + * + * This function changes properties of LEB @lnum. It is a helper wrapper over + * 'ubifs_change_lp()' which hides lprops get/release. The arguments are the + * same as in case of 'ubifs_change_lp()'. Returns zero in case of success and + * a negative error code in case of failure. + */ +int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty, + int flags_set, int flags_clean, int idx_gc_cnt) +{ + int err = 0, flags; + const struct ubifs_lprops *lp; + + ubifs_get_lprops(c); + + lp = ubifs_lpt_lookup_dirty(c, lnum); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + goto out; + } + + flags = (lp->flags | flags_set) & ~flags_clean; + lp = ubifs_change_lp(c, lp, free, dirty, flags, idx_gc_cnt); + if (IS_ERR(lp)) + err = PTR_ERR(lp); + +out: + ubifs_release_lprops(c); + return err; +} + +/** + * ubifs_update_one_lp - update LEB properties. + * @c: the UBIFS file-system description object + * @lnum: LEB to change properties for + * @free: amount of free space + * @dirty: amount of dirty space to add + * @flags_set: flags to set + * @flags_clean: flags to clean + * + * This function is the same as 'ubifs_change_one_lp()' but @dirty is added to + * current dirty space, not substitutes it. + */ +int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty, + int flags_set, int flags_clean) +{ + int err = 0, flags; + const struct ubifs_lprops *lp; + + ubifs_get_lprops(c); + + lp = ubifs_lpt_lookup_dirty(c, lnum); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + goto out; + } + + flags = (lp->flags | flags_set) & ~flags_clean; + lp = ubifs_change_lp(c, lp, free, lp->dirty + dirty, flags, 0); + if (IS_ERR(lp)) + err = PTR_ERR(lp); + +out: + ubifs_release_lprops(c); + return err; +} + +/** + * ubifs_read_one_lp - read LEB properties. + * @c: the UBIFS file-system description object + * @lnum: LEB to read properties for + * @lp: where to store read properties + * + * This helper function reads properties of a LEB @lnum and stores them in @lp. + * Returns zero in case of success and a negative error code in case of + * failure. + */ +int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp) +{ + int err = 0; + const struct ubifs_lprops *lpp; + + ubifs_get_lprops(c); + + lpp = ubifs_lpt_lookup(c, lnum); + if (IS_ERR(lpp)) { + err = PTR_ERR(lpp); + goto out; + } + + memcpy(lp, lpp, sizeof(struct ubifs_lprops)); + +out: + ubifs_release_lprops(c); + return err; +} + +/** + * ubifs_fast_find_free - try to find a LEB with free space quickly. + * @c: the UBIFS file-system description object + * + * This function returns LEB properties for a LEB with free space or %NULL if + * the function is unable to find a LEB quickly. + */ +const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c) +{ + struct ubifs_lprops *lprops; + struct ubifs_lpt_heap *heap; + + ubifs_assert(mutex_is_locked(&c->lp_mutex)); + + heap = &c->lpt_heap[LPROPS_FREE - 1]; + if (heap->cnt == 0) + return NULL; + + lprops = heap->arr[0]; + ubifs_assert(!(lprops->flags & LPROPS_TAKEN)); + ubifs_assert(!(lprops->flags & LPROPS_INDEX)); + return lprops; +} + +/** + * ubifs_fast_find_empty - try to find an empty LEB quickly. + * @c: the UBIFS file-system description object + * + * This function returns LEB properties for an empty LEB or %NULL if the + * function is unable to find an empty LEB quickly. + */ +const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c) +{ + struct ubifs_lprops *lprops; + + ubifs_assert(mutex_is_locked(&c->lp_mutex)); + + if (list_empty(&c->empty_list)) + return NULL; + + lprops = list_entry(c->empty_list.next, struct ubifs_lprops, list); + ubifs_assert(!(lprops->flags & LPROPS_TAKEN)); + ubifs_assert(!(lprops->flags & LPROPS_INDEX)); + ubifs_assert(lprops->free == c->leb_size); + return lprops; +} + +/** + * ubifs_fast_find_freeable - try to find a freeable LEB quickly. + * @c: the UBIFS file-system description object + * + * This function returns LEB properties for a freeable LEB or %NULL if the + * function is unable to find a freeable LEB quickly. + */ +const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c) +{ + struct ubifs_lprops *lprops; + + ubifs_assert(mutex_is_locked(&c->lp_mutex)); + + if (list_empty(&c->freeable_list)) + return NULL; + + lprops = list_entry(c->freeable_list.next, struct ubifs_lprops, list); + ubifs_assert(!(lprops->flags & LPROPS_TAKEN)); + ubifs_assert(!(lprops->flags & LPROPS_INDEX)); + ubifs_assert(lprops->free + lprops->dirty == c->leb_size); + ubifs_assert(c->freeable_cnt > 0); + return lprops; +} + +/** + * ubifs_fast_find_frdi_idx - try to find a freeable index LEB quickly. + * @c: the UBIFS file-system description object + * + * This function returns LEB properties for a freeable index LEB or %NULL if the + * function is unable to find a freeable index LEB quickly. + */ +const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c) +{ + struct ubifs_lprops *lprops; + + ubifs_assert(mutex_is_locked(&c->lp_mutex)); + + if (list_empty(&c->frdi_idx_list)) + return NULL; + + lprops = list_entry(c->frdi_idx_list.next, struct ubifs_lprops, list); + ubifs_assert(!(lprops->flags & LPROPS_TAKEN)); + ubifs_assert((lprops->flags & LPROPS_INDEX)); + ubifs_assert(lprops->free + lprops->dirty == c->leb_size); + return lprops; +} diff --git a/fs/ubifs/lpt.c b/fs/ubifs/lpt.c new file mode 100644 index 0000000..1a50d4c --- /dev/null +++ b/fs/ubifs/lpt.c @@ -0,0 +1,1105 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements the LEB properties tree (LPT) area. The LPT area + * contains the LEB properties tree, a table of LPT area eraseblocks (ltab), and + * (for the "big" model) a table of saved LEB numbers (lsave). The LPT area sits + * between the log and the orphan area. + * + * The LPT area is like a miniature self-contained file system. It is required + * that it never runs out of space, is fast to access and update, and scales + * logarithmically. The LEB properties tree is implemented as a wandering tree + * much like the TNC, and the LPT area has its own garbage collection. + * + * The LPT has two slightly different forms called the "small model" and the + * "big model". The small model is used when the entire LEB properties table + * can be written into a single eraseblock. In that case, garbage collection + * consists of just writing the whole table, which therefore makes all other + * eraseblocks reusable. In the case of the big model, dirty eraseblocks are + * selected for garbage collection, which consists of marking the clean nodes in + * that LEB as dirty, and then only the dirty nodes are written out. Also, in + * the case of the big model, a table of LEB numbers is saved so that the entire + * LPT does not to be scanned looking for empty eraseblocks when UBIFS is first + * mounted. + */ + +#include "ubifs.h" +#include "crc16.h" +#include <linux/math64.h> + +/** + * do_calc_lpt_geom - calculate sizes for the LPT area. + * @c: the UBIFS file-system description object + * + * Calculate the sizes of LPT bit fields, nodes, and tree, based on the + * properties of the flash and whether LPT is "big" (c->big_lpt). + */ +static void do_calc_lpt_geom(struct ubifs_info *c) +{ + int i, n, bits, per_leb_wastage, max_pnode_cnt; + long long sz, tot_wastage; + + n = c->main_lebs + c->max_leb_cnt - c->leb_cnt; + max_pnode_cnt = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT); + + c->lpt_hght = 1; + n = UBIFS_LPT_FANOUT; + while (n < max_pnode_cnt) { + c->lpt_hght += 1; + n <<= UBIFS_LPT_FANOUT_SHIFT; + } + + c->pnode_cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT); + + n = DIV_ROUND_UP(c->pnode_cnt, UBIFS_LPT_FANOUT); + c->nnode_cnt = n; + for (i = 1; i < c->lpt_hght; i++) { + n = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT); + c->nnode_cnt += n; + } + + c->space_bits = fls(c->leb_size) - 3; + c->lpt_lnum_bits = fls(c->lpt_lebs); + c->lpt_offs_bits = fls(c->leb_size - 1); + c->lpt_spc_bits = fls(c->leb_size); + + n = DIV_ROUND_UP(c->max_leb_cnt, UBIFS_LPT_FANOUT); + c->pcnt_bits = fls(n - 1); + + c->lnum_bits = fls(c->max_leb_cnt - 1); + + bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS + + (c->big_lpt ? c->pcnt_bits : 0) + + (c->space_bits * 2 + 1) * UBIFS_LPT_FANOUT; + c->pnode_sz = (bits + 7) / 8; + + bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS + + (c->big_lpt ? c->pcnt_bits : 0) + + (c->lpt_lnum_bits + c->lpt_offs_bits) * UBIFS_LPT_FANOUT; + c->nnode_sz = (bits + 7) / 8; + + bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS + + c->lpt_lebs * c->lpt_spc_bits * 2; + c->ltab_sz = (bits + 7) / 8; + + bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS + + c->lnum_bits * c->lsave_cnt; + c->lsave_sz = (bits + 7) / 8; + + /* Calculate the minimum LPT size */ + c->lpt_sz = (long long)c->pnode_cnt * c->pnode_sz; + c->lpt_sz += (long long)c->nnode_cnt * c->nnode_sz; + c->lpt_sz += c->ltab_sz; + if (c->big_lpt) + c->lpt_sz += c->lsave_sz; + + /* Add wastage */ + sz = c->lpt_sz; + per_leb_wastage = max_t(int, c->pnode_sz, c->nnode_sz); + sz += per_leb_wastage; + tot_wastage = per_leb_wastage; + while (sz > c->leb_size) { + sz += per_leb_wastage; + sz -= c->leb_size; + tot_wastage += per_leb_wastage; + } + tot_wastage += ALIGN(sz, c->min_io_size) - sz; + c->lpt_sz += tot_wastage; +} + +/** + * ubifs_calc_lpt_geom - calculate and check sizes for the LPT area. + * @c: the UBIFS file-system description object + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_calc_lpt_geom(struct ubifs_info *c) +{ + int lebs_needed; + long long sz; + + do_calc_lpt_geom(c); + + /* Verify that lpt_lebs is big enough */ + sz = c->lpt_sz * 2; /* Must have at least 2 times the size */ + lebs_needed = div_u64(sz + c->leb_size - 1, c->leb_size); + if (lebs_needed > c->lpt_lebs) { + ubifs_err("too few LPT LEBs"); + return -EINVAL; + } + + /* Verify that ltab fits in a single LEB (since ltab is a single node */ + if (c->ltab_sz > c->leb_size) { + ubifs_err("LPT ltab too big"); + return -EINVAL; + } + + c->check_lpt_free = c->big_lpt; + return 0; +} + +/** + * ubifs_unpack_bits - unpack bit fields. + * @addr: address at which to unpack (passed and next address returned) + * @pos: bit position at which to unpack (passed and next position returned) + * @nrbits: number of bits of value to unpack (1-32) + * + * This functions returns the value unpacked. + */ +uint32_t ubifs_unpack_bits(uint8_t **addr, int *pos, int nrbits) +{ + const int k = 32 - nrbits; + uint8_t *p = *addr; + int b = *pos; + uint32_t uninitialized_var(val); + const int bytes = (nrbits + b + 7) >> 3; + + ubifs_assert(nrbits > 0); + ubifs_assert(nrbits <= 32); + ubifs_assert(*pos >= 0); + ubifs_assert(*pos < 8); + if (b) { + switch (bytes) { + case 2: + val = p[1]; + break; + case 3: + val = p[1] | ((uint32_t)p[2] << 8); + break; + case 4: + val = p[1] | ((uint32_t)p[2] << 8) | + ((uint32_t)p[3] << 16); + break; + case 5: + val = p[1] | ((uint32_t)p[2] << 8) | + ((uint32_t)p[3] << 16) | + ((uint32_t)p[4] << 24); + } + val <<= (8 - b); + val |= *p >> b; + nrbits += b; + } else { + switch (bytes) { + case 1: + val = p[0]; + break; + case 2: + val = p[0] | ((uint32_t)p[1] << 8); + break; + case 3: + val = p[0] | ((uint32_t)p[1] << 8) | + ((uint32_t)p[2] << 16); + break; + case 4: + val = p[0] | ((uint32_t)p[1] << 8) | + ((uint32_t)p[2] << 16) | + ((uint32_t)p[3] << 24); + break; + } + } + val <<= k; + val >>= k; + b = nrbits & 7; + p += nrbits >> 3; + *addr = p; + *pos = b; + ubifs_assert((val >> nrbits) == 0 || nrbits - b == 32); + return val; +} + +/** + * ubifs_add_lpt_dirt - add dirty space to LPT LEB properties. + * @c: UBIFS file-system description object + * @lnum: LEB number to which to add dirty space + * @dirty: amount of dirty space to add + */ +void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty) +{ + if (!dirty || !lnum) + return; + dbg_lp("LEB %d add %d to %d", + lnum, dirty, c->ltab[lnum - c->lpt_first].dirty); + ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last); + c->ltab[lnum - c->lpt_first].dirty += dirty; +} + +/** + * ubifs_add_nnode_dirt - add dirty space to LPT LEB properties. + * @c: UBIFS file-system description object + * @nnode: nnode for which to add dirt + */ +void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode) +{ + struct ubifs_nnode *np = nnode->parent; + + if (np) + ubifs_add_lpt_dirt(c, np->nbranch[nnode->iip].lnum, + c->nnode_sz); + else { + ubifs_add_lpt_dirt(c, c->lpt_lnum, c->nnode_sz); + if (!(c->lpt_drty_flgs & LTAB_DIRTY)) { + c->lpt_drty_flgs |= LTAB_DIRTY; + ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz); + } + } +} + +/** + * add_pnode_dirt - add dirty space to LPT LEB properties. + * @c: UBIFS file-system description object + * @pnode: pnode for which to add dirt + */ +static void add_pnode_dirt(struct ubifs_info *c, struct ubifs_pnode *pnode) +{ + ubifs_add_lpt_dirt(c, pnode->parent->nbranch[pnode->iip].lnum, + c->pnode_sz); +} + +/** + * calc_nnode_num_from_parent - calculate nnode number. + * @c: UBIFS file-system description object + * @parent: parent nnode + * @iip: index in parent + * + * The nnode number is a number that uniquely identifies a nnode and can be used + * easily to traverse the tree from the root to that nnode. + * + * This function calculates and returns the nnode number based on the parent's + * nnode number and the index in parent. + */ +static int calc_nnode_num_from_parent(const struct ubifs_info *c, + struct ubifs_nnode *parent, int iip) +{ + int num, shft; + + if (!parent) + return 1; + shft = (c->lpt_hght - parent->level) * UBIFS_LPT_FANOUT_SHIFT; + num = parent->num ^ (1 << shft); + num |= (UBIFS_LPT_FANOUT + iip) << shft; + return num; +} + +/** + * calc_pnode_num_from_parent - calculate pnode number. + * @c: UBIFS file-system description object + * @parent: parent nnode + * @iip: index in parent + * + * The pnode number is a number that uniquely identifies a pnode and can be used + * easily to traverse the tree from the root to that pnode. + * + * This function calculates and returns the pnode number based on the parent's + * nnode number and the index in parent. + */ +static int calc_pnode_num_from_parent(const struct ubifs_info *c, + struct ubifs_nnode *parent, int iip) +{ + int i, n = c->lpt_hght - 1, pnum = parent->num, num = 0; + + for (i = 0; i < n; i++) { + num <<= UBIFS_LPT_FANOUT_SHIFT; + num |= pnum & (UBIFS_LPT_FANOUT - 1); + pnum >>= UBIFS_LPT_FANOUT_SHIFT; + } + num <<= UBIFS_LPT_FANOUT_SHIFT; + num |= iip; + return num; +} + +/** + * update_cats - add LEB properties of a pnode to LEB category lists and heaps. + * @c: UBIFS file-system description object + * @pnode: pnode + * + * When a pnode is loaded into memory, the LEB properties it contains are added, + * by this function, to the LEB category lists and heaps. + */ +static void update_cats(struct ubifs_info *c, struct ubifs_pnode *pnode) +{ + int i; + + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + int cat = pnode->lprops[i].flags & LPROPS_CAT_MASK; + int lnum = pnode->lprops[i].lnum; + + if (!lnum) + return; + ubifs_add_to_cat(c, &pnode->lprops[i], cat); + } +} + +/** + * replace_cats - add LEB properties of a pnode to LEB category lists and heaps. + * @c: UBIFS file-system description object + * @old_pnode: pnode copied + * @new_pnode: pnode copy + * + * During commit it is sometimes necessary to copy a pnode + * (see dirty_cow_pnode). When that happens, references in + * category lists and heaps must be replaced. This function does that. + */ +static void replace_cats(struct ubifs_info *c, struct ubifs_pnode *old_pnode, + struct ubifs_pnode *new_pnode) +{ + int i; + + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + if (!new_pnode->lprops[i].lnum) + return; + ubifs_replace_cat(c, &old_pnode->lprops[i], + &new_pnode->lprops[i]); + } +} + +/** + * check_lpt_crc - check LPT node crc is correct. + * @c: UBIFS file-system description object + * @buf: buffer containing node + * @len: length of node + * + * This function returns %0 on success and a negative error code on failure. + */ +static int check_lpt_crc(void *buf, int len) +{ + int pos = 0; + uint8_t *addr = buf; + uint16_t crc, calc_crc; + + crc = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_CRC_BITS); + calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES, + len - UBIFS_LPT_CRC_BYTES); + if (crc != calc_crc) { + ubifs_err("invalid crc in LPT node: crc %hx calc %hx", crc, + calc_crc); + dbg_dump_stack(); + return -EINVAL; + } + return 0; +} + +/** + * check_lpt_type - check LPT node type is correct. + * @c: UBIFS file-system description object + * @addr: address of type bit field is passed and returned updated here + * @pos: position of type bit field is passed and returned updated here + * @type: expected type + * + * This function returns %0 on success and a negative error code on failure. + */ +static int check_lpt_type(uint8_t **addr, int *pos, int type) +{ + int node_type; + + node_type = ubifs_unpack_bits(addr, pos, UBIFS_LPT_TYPE_BITS); + if (node_type != type) { + ubifs_err("invalid type (%d) in LPT node type %d", node_type, + type); + dbg_dump_stack(); + return -EINVAL; + } + return 0; +} + +/** + * unpack_pnode - unpack a pnode. + * @c: UBIFS file-system description object + * @buf: buffer containing packed pnode to unpack + * @pnode: pnode structure to fill + * + * This function returns %0 on success and a negative error code on failure. + */ +static int unpack_pnode(const struct ubifs_info *c, void *buf, + struct ubifs_pnode *pnode) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0, err; + + err = check_lpt_type(&addr, &pos, UBIFS_LPT_PNODE); + if (err) + return err; + if (c->big_lpt) + pnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits); + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + struct ubifs_lprops * const lprops = &pnode->lprops[i]; + + lprops->free = ubifs_unpack_bits(&addr, &pos, c->space_bits); + lprops->free <<= 3; + lprops->dirty = ubifs_unpack_bits(&addr, &pos, c->space_bits); + lprops->dirty <<= 3; + + if (ubifs_unpack_bits(&addr, &pos, 1)) + lprops->flags = LPROPS_INDEX; + else + lprops->flags = 0; + lprops->flags |= ubifs_categorize_lprops(c, lprops); + } + err = check_lpt_crc(buf, c->pnode_sz); + return err; +} + +/** + * ubifs_unpack_nnode - unpack a nnode. + * @c: UBIFS file-system description object + * @buf: buffer containing packed nnode to unpack + * @nnode: nnode structure to fill + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_unpack_nnode(const struct ubifs_info *c, void *buf, + struct ubifs_nnode *nnode) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0, err; + + err = check_lpt_type(&addr, &pos, UBIFS_LPT_NNODE); + if (err) + return err; + if (c->big_lpt) + nnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits); + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + int lnum; + + lnum = ubifs_unpack_bits(&addr, &pos, c->lpt_lnum_bits) + + c->lpt_first; + if (lnum == c->lpt_last + 1) + lnum = 0; + nnode->nbranch[i].lnum = lnum; + nnode->nbranch[i].offs = ubifs_unpack_bits(&addr, &pos, + c->lpt_offs_bits); + } + err = check_lpt_crc(buf, c->nnode_sz); + return err; +} + +/** + * unpack_ltab - unpack the LPT's own lprops table. + * @c: UBIFS file-system description object + * @buf: buffer from which to unpack + * + * This function returns %0 on success and a negative error code on failure. + */ +static int unpack_ltab(const struct ubifs_info *c, void *buf) +{ + uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES; + int i, pos = 0, err; + + err = check_lpt_type(&addr, &pos, UBIFS_LPT_LTAB); + if (err) + return err; + for (i = 0; i < c->lpt_lebs; i++) { + int free = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits); + int dirty = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits); + + if (free < 0 || free > c->leb_size || dirty < 0 || + dirty > c->leb_size || free + dirty > c->leb_size) + return -EINVAL; + + c->ltab[i].free = free; + c->ltab[i].dirty = dirty; + c->ltab[i].tgc = 0; + c->ltab[i].cmt = 0; + } + err = check_lpt_crc(buf, c->ltab_sz); + return err; +} + +/** + * validate_nnode - validate a nnode. + * @c: UBIFS file-system description object + * @nnode: nnode to validate + * @parent: parent nnode (or NULL for the root nnode) + * @iip: index in parent + * + * This function returns %0 on success and a negative error code on failure. + */ +static int validate_nnode(const struct ubifs_info *c, struct ubifs_nnode *nnode, + struct ubifs_nnode *parent, int iip) +{ + int i, lvl, max_offs; + + if (c->big_lpt) { + int num = calc_nnode_num_from_parent(c, parent, iip); + + if (nnode->num != num) + return -EINVAL; + } + lvl = parent ? parent->level - 1 : c->lpt_hght; + if (lvl < 1) + return -EINVAL; + if (lvl == 1) + max_offs = c->leb_size - c->pnode_sz; + else + max_offs = c->leb_size - c->nnode_sz; + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + int lnum = nnode->nbranch[i].lnum; + int offs = nnode->nbranch[i].offs; + + if (lnum == 0) { + if (offs != 0) + return -EINVAL; + continue; + } + if (lnum < c->lpt_first || lnum > c->lpt_last) + return -EINVAL; + if (offs < 0 || offs > max_offs) + return -EINVAL; + } + return 0; +} + +/** + * validate_pnode - validate a pnode. + * @c: UBIFS file-system description object + * @pnode: pnode to validate + * @parent: parent nnode + * @iip: index in parent + * + * This function returns %0 on success and a negative error code on failure. + */ +static int validate_pnode(const struct ubifs_info *c, struct ubifs_pnode *pnode, + struct ubifs_nnode *parent, int iip) +{ + int i; + + if (c->big_lpt) { + int num = calc_pnode_num_from_parent(c, parent, iip); + + if (pnode->num != num) + return -EINVAL; + } + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + int free = pnode->lprops[i].free; + int dirty = pnode->lprops[i].dirty; + + if (free < 0 || free > c->leb_size || free % c->min_io_size || + (free & 7)) + return -EINVAL; + if (dirty < 0 || dirty > c->leb_size || (dirty & 7)) + return -EINVAL; + if (dirty + free > c->leb_size) + return -EINVAL; + } + return 0; +} + +/** + * set_pnode_lnum - set LEB numbers on a pnode. + * @c: UBIFS file-system description object + * @pnode: pnode to update + * + * This function calculates the LEB numbers for the LEB properties it contains + * based on the pnode number. + */ +static void set_pnode_lnum(const struct ubifs_info *c, + struct ubifs_pnode *pnode) +{ + int i, lnum; + + lnum = (pnode->num << UBIFS_LPT_FANOUT_SHIFT) + c->main_first; + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + if (lnum >= c->leb_cnt) + return; + pnode->lprops[i].lnum = lnum++; + } +} + +/** + * ubifs_read_nnode - read a nnode from flash and link it to the tree in memory. + * @c: UBIFS file-system description object + * @parent: parent nnode (or NULL for the root) + * @iip: index in parent + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip) +{ + struct ubifs_nbranch *branch = NULL; + struct ubifs_nnode *nnode = NULL; + void *buf = c->lpt_nod_buf; + int err, lnum, offs; + + if (parent) { + branch = &parent->nbranch[iip]; + lnum = branch->lnum; + offs = branch->offs; + } else { + lnum = c->lpt_lnum; + offs = c->lpt_offs; + } + nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_NOFS); + if (!nnode) { + err = -ENOMEM; + goto out; + } + if (lnum == 0) { + /* + * This nnode was not written which just means that the LEB + * properties in the subtree below it describe empty LEBs. We + * make the nnode as though we had read it, which in fact means + * doing almost nothing. + */ + if (c->big_lpt) + nnode->num = calc_nnode_num_from_parent(c, parent, iip); + } else { + err = ubi_read(c->ubi, lnum, buf, offs, c->nnode_sz); + if (err) + goto out; + err = ubifs_unpack_nnode(c, buf, nnode); + if (err) + goto out; + } + err = validate_nnode(c, nnode, parent, iip); + if (err) + goto out; + if (!c->big_lpt) + nnode->num = calc_nnode_num_from_parent(c, parent, iip); + if (parent) { + branch->nnode = nnode; + nnode->level = parent->level - 1; + } else { + c->nroot = nnode; + nnode->level = c->lpt_hght; + } + nnode->parent = parent; + nnode->iip = iip; + return 0; + +out: + ubifs_err("error %d reading nnode at %d:%d", err, lnum, offs); + kfree(nnode); + return err; +} + +/** + * read_pnode - read a pnode from flash and link it to the tree in memory. + * @c: UBIFS file-system description object + * @parent: parent nnode + * @iip: index in parent + * + * This function returns %0 on success and a negative error code on failure. + */ +static int read_pnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip) +{ + struct ubifs_nbranch *branch; + struct ubifs_pnode *pnode = NULL; + void *buf = c->lpt_nod_buf; + int err, lnum, offs; + + branch = &parent->nbranch[iip]; + lnum = branch->lnum; + offs = branch->offs; + pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_NOFS); + if (!pnode) { + err = -ENOMEM; + goto out; + } + if (lnum == 0) { + /* + * This pnode was not written which just means that the LEB + * properties in it describe empty LEBs. We make the pnode as + * though we had read it. + */ + int i; + + if (c->big_lpt) + pnode->num = calc_pnode_num_from_parent(c, parent, iip); + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + struct ubifs_lprops * const lprops = &pnode->lprops[i]; + + lprops->free = c->leb_size; + lprops->flags = ubifs_categorize_lprops(c, lprops); + } + } else { + err = ubi_read(c->ubi, lnum, buf, offs, c->pnode_sz); + if (err) + goto out; + err = unpack_pnode(c, buf, pnode); + if (err) + goto out; + } + err = validate_pnode(c, pnode, parent, iip); + if (err) + goto out; + if (!c->big_lpt) + pnode->num = calc_pnode_num_from_parent(c, parent, iip); + branch->pnode = pnode; + pnode->parent = parent; + pnode->iip = iip; + set_pnode_lnum(c, pnode); + c->pnodes_have += 1; + return 0; + +out: + ubifs_err("error %d reading pnode at %d:%d", err, lnum, offs); + dbg_dump_pnode(c, pnode, parent, iip); + dbg_msg("calc num: %d", calc_pnode_num_from_parent(c, parent, iip)); + kfree(pnode); + return err; +} + +/** + * read_ltab - read LPT's own lprops table. + * @c: UBIFS file-system description object + * + * This function returns %0 on success and a negative error code on failure. + */ +static int read_ltab(struct ubifs_info *c) +{ + int err; + void *buf; + + buf = vmalloc(c->ltab_sz); + if (!buf) + return -ENOMEM; + err = ubi_read(c->ubi, c->ltab_lnum, buf, c->ltab_offs, c->ltab_sz); + if (err) + goto out; + err = unpack_ltab(c, buf); +out: + vfree(buf); + return err; +} + +/** + * ubifs_get_nnode - get a nnode. + * @c: UBIFS file-system description object + * @parent: parent nnode (or NULL for the root) + * @iip: index in parent + * + * This function returns a pointer to the nnode on success or a negative error + * code on failure. + */ +struct ubifs_nnode *ubifs_get_nnode(struct ubifs_info *c, + struct ubifs_nnode *parent, int iip) +{ + struct ubifs_nbranch *branch; + struct ubifs_nnode *nnode; + int err; + + branch = &parent->nbranch[iip]; + nnode = branch->nnode; + if (nnode) + return nnode; + err = ubifs_read_nnode(c, parent, iip); + if (err) + return ERR_PTR(err); + return branch->nnode; +} + +/** + * ubifs_get_pnode - get a pnode. + * @c: UBIFS file-system description object + * @parent: parent nnode + * @iip: index in parent + * + * This function returns a pointer to the pnode on success or a negative error + * code on failure. + */ +struct ubifs_pnode *ubifs_get_pnode(struct ubifs_info *c, + struct ubifs_nnode *parent, int iip) +{ + struct ubifs_nbranch *branch; + struct ubifs_pnode *pnode; + int err; + + branch = &parent->nbranch[iip]; + pnode = branch->pnode; + if (pnode) + return pnode; + err = read_pnode(c, parent, iip); + if (err) + return ERR_PTR(err); + update_cats(c, branch->pnode); + return branch->pnode; +} + +/** + * ubifs_lpt_lookup - lookup LEB properties in the LPT. + * @c: UBIFS file-system description object + * @lnum: LEB number to lookup + * + * This function returns a pointer to the LEB properties on success or a + * negative error code on failure. + */ +struct ubifs_lprops *ubifs_lpt_lookup(struct ubifs_info *c, int lnum) +{ + int err, i, h, iip, shft; + struct ubifs_nnode *nnode; + struct ubifs_pnode *pnode; + + if (!c->nroot) { + err = ubifs_read_nnode(c, NULL, 0); + if (err) + return ERR_PTR(err); + } + nnode = c->nroot; + i = lnum - c->main_first; + shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT; + for (h = 1; h < c->lpt_hght; h++) { + iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); + shft -= UBIFS_LPT_FANOUT_SHIFT; + nnode = ubifs_get_nnode(c, nnode, iip); + if (IS_ERR(nnode)) + return ERR_PTR(PTR_ERR(nnode)); + } + iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); + shft -= UBIFS_LPT_FANOUT_SHIFT; + pnode = ubifs_get_pnode(c, nnode, iip); + if (IS_ERR(pnode)) + return ERR_PTR(PTR_ERR(pnode)); + iip = (i & (UBIFS_LPT_FANOUT - 1)); + dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum, + pnode->lprops[iip].free, pnode->lprops[iip].dirty, + pnode->lprops[iip].flags); + return &pnode->lprops[iip]; +} + +/** + * dirty_cow_nnode - ensure a nnode is not being committed. + * @c: UBIFS file-system description object + * @nnode: nnode to check + * + * Returns dirtied nnode on success or negative error code on failure. + */ +static struct ubifs_nnode *dirty_cow_nnode(struct ubifs_info *c, + struct ubifs_nnode *nnode) +{ + struct ubifs_nnode *n; + int i; + + if (!test_bit(COW_CNODE, &nnode->flags)) { + /* nnode is not being committed */ + if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) { + c->dirty_nn_cnt += 1; + ubifs_add_nnode_dirt(c, nnode); + } + return nnode; + } + + /* nnode is being committed, so copy it */ + n = kmalloc(sizeof(struct ubifs_nnode), GFP_NOFS); + if (unlikely(!n)) + return ERR_PTR(-ENOMEM); + + memcpy(n, nnode, sizeof(struct ubifs_nnode)); + n->cnext = NULL; + __set_bit(DIRTY_CNODE, &n->flags); + __clear_bit(COW_CNODE, &n->flags); + + /* The children now have new parent */ + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + struct ubifs_nbranch *branch = &n->nbranch[i]; + + if (branch->cnode) + branch->cnode->parent = n; + } + + ubifs_assert(!test_bit(OBSOLETE_CNODE, &nnode->flags)); + __set_bit(OBSOLETE_CNODE, &nnode->flags); + + c->dirty_nn_cnt += 1; + ubifs_add_nnode_dirt(c, nnode); + if (nnode->parent) + nnode->parent->nbranch[n->iip].nnode = n; + else + c->nroot = n; + return n; +} + +/** + * dirty_cow_pnode - ensure a pnode is not being committed. + * @c: UBIFS file-system description object + * @pnode: pnode to check + * + * Returns dirtied pnode on success or negative error code on failure. + */ +static struct ubifs_pnode *dirty_cow_pnode(struct ubifs_info *c, + struct ubifs_pnode *pnode) +{ + struct ubifs_pnode *p; + + if (!test_bit(COW_CNODE, &pnode->flags)) { + /* pnode is not being committed */ + if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) { + c->dirty_pn_cnt += 1; + add_pnode_dirt(c, pnode); + } + return pnode; + } + + /* pnode is being committed, so copy it */ + p = kmalloc(sizeof(struct ubifs_pnode), GFP_NOFS); + if (unlikely(!p)) + return ERR_PTR(-ENOMEM); + + memcpy(p, pnode, sizeof(struct ubifs_pnode)); + p->cnext = NULL; + __set_bit(DIRTY_CNODE, &p->flags); + __clear_bit(COW_CNODE, &p->flags); + replace_cats(c, pnode, p); + + ubifs_assert(!test_bit(OBSOLETE_CNODE, &pnode->flags)); + __set_bit(OBSOLETE_CNODE, &pnode->flags); + + c->dirty_pn_cnt += 1; + add_pnode_dirt(c, pnode); + pnode->parent->nbranch[p->iip].pnode = p; + return p; +} + +/** + * ubifs_lpt_lookup_dirty - lookup LEB properties in the LPT. + * @c: UBIFS file-system description object + * @lnum: LEB number to lookup + * + * This function returns a pointer to the LEB properties on success or a + * negative error code on failure. + */ +struct ubifs_lprops *ubifs_lpt_lookup_dirty(struct ubifs_info *c, int lnum) +{ + int err, i, h, iip, shft; + struct ubifs_nnode *nnode; + struct ubifs_pnode *pnode; + + if (!c->nroot) { + err = ubifs_read_nnode(c, NULL, 0); + if (err) + return ERR_PTR(err); + } + nnode = c->nroot; + nnode = dirty_cow_nnode(c, nnode); + if (IS_ERR(nnode)) + return ERR_PTR(PTR_ERR(nnode)); + i = lnum - c->main_first; + shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT; + for (h = 1; h < c->lpt_hght; h++) { + iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); + shft -= UBIFS_LPT_FANOUT_SHIFT; + nnode = ubifs_get_nnode(c, nnode, iip); + if (IS_ERR(nnode)) + return ERR_PTR(PTR_ERR(nnode)); + nnode = dirty_cow_nnode(c, nnode); + if (IS_ERR(nnode)) + return ERR_PTR(PTR_ERR(nnode)); + } + iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1)); + shft -= UBIFS_LPT_FANOUT_SHIFT; + pnode = ubifs_get_pnode(c, nnode, iip); + if (IS_ERR(pnode)) + return ERR_PTR(PTR_ERR(pnode)); + pnode = dirty_cow_pnode(c, pnode); + if (IS_ERR(pnode)) + return ERR_PTR(PTR_ERR(pnode)); + iip = (i & (UBIFS_LPT_FANOUT - 1)); + dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum, + pnode->lprops[iip].free, pnode->lprops[iip].dirty, + pnode->lprops[iip].flags); + ubifs_assert(test_bit(DIRTY_CNODE, &pnode->flags)); + return &pnode->lprops[iip]; +} + +/** + * lpt_init_rd - initialize the LPT for reading. + * @c: UBIFS file-system description object + * + * This function returns %0 on success and a negative error code on failure. + */ +static int lpt_init_rd(struct ubifs_info *c) +{ + int err, i; + + c->ltab = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs); + if (!c->ltab) + return -ENOMEM; + + i = max_t(int, c->nnode_sz, c->pnode_sz); + c->lpt_nod_buf = kmalloc(i, GFP_KERNEL); + if (!c->lpt_nod_buf) + return -ENOMEM; + + for (i = 0; i < LPROPS_HEAP_CNT; i++) { + c->lpt_heap[i].arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ, + GFP_KERNEL); + if (!c->lpt_heap[i].arr) + return -ENOMEM; + c->lpt_heap[i].cnt = 0; + c->lpt_heap[i].max_cnt = LPT_HEAP_SZ; + } + + c->dirty_idx.arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ, GFP_KERNEL); + if (!c->dirty_idx.arr) + return -ENOMEM; + c->dirty_idx.cnt = 0; + c->dirty_idx.max_cnt = LPT_HEAP_SZ; + + err = read_ltab(c); + if (err) + return err; + + dbg_lp("space_bits %d", c->space_bits); + dbg_lp("lpt_lnum_bits %d", c->lpt_lnum_bits); + dbg_lp("lpt_offs_bits %d", c->lpt_offs_bits); + dbg_lp("lpt_spc_bits %d", c->lpt_spc_bits); + dbg_lp("pcnt_bits %d", c->pcnt_bits); + dbg_lp("lnum_bits %d", c->lnum_bits); + dbg_lp("pnode_sz %d", c->pnode_sz); + dbg_lp("nnode_sz %d", c->nnode_sz); + dbg_lp("ltab_sz %d", c->ltab_sz); + dbg_lp("lsave_sz %d", c->lsave_sz); + dbg_lp("lsave_cnt %d", c->lsave_cnt); + dbg_lp("lpt_hght %d", c->lpt_hght); + dbg_lp("big_lpt %d", c->big_lpt); + dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs); + dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs); + dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs); + if (c->big_lpt) + dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs); + + return 0; +} + +/** + * ubifs_lpt_init - initialize the LPT. + * @c: UBIFS file-system description object + * @rd: whether to initialize lpt for reading + * @wr: whether to initialize lpt for writing + * + * For mounting 'rw', @rd and @wr are both true. For mounting 'ro', @rd is true + * and @wr is false. For mounting from 'ro' to 'rw', @rd is false and @wr is + * true. + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_lpt_init(struct ubifs_info *c, int rd, int wr) +{ + int err; + + if (rd) { + err = lpt_init_rd(c); + if (err) + return err; + } + + return 0; +} diff --git a/fs/ubifs/lpt_commit.c b/fs/ubifs/lpt_commit.c new file mode 100644 index 0000000..c0af818 --- /dev/null +++ b/fs/ubifs/lpt_commit.c @@ -0,0 +1,171 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements commit-related functionality of the LEB properties + * subsystem. + */ + +#include "crc16.h" +#include "ubifs.h" + +/** + * free_obsolete_cnodes - free obsolete cnodes for commit end. + * @c: UBIFS file-system description object + */ +static void free_obsolete_cnodes(struct ubifs_info *c) +{ + struct ubifs_cnode *cnode, *cnext; + + cnext = c->lpt_cnext; + if (!cnext) + return; + do { + cnode = cnext; + cnext = cnode->cnext; + if (test_bit(OBSOLETE_CNODE, &cnode->flags)) + kfree(cnode); + else + cnode->cnext = NULL; + } while (cnext != c->lpt_cnext); + c->lpt_cnext = NULL; +} + +/** + * first_nnode - find the first nnode in memory. + * @c: UBIFS file-system description object + * @hght: height of tree where nnode found is returned here + * + * This function returns a pointer to the nnode found or %NULL if no nnode is + * found. This function is a helper to 'ubifs_lpt_free()'. + */ +static struct ubifs_nnode *first_nnode(struct ubifs_info *c, int *hght) +{ + struct ubifs_nnode *nnode; + int h, i, found; + + nnode = c->nroot; + *hght = 0; + if (!nnode) + return NULL; + for (h = 1; h < c->lpt_hght; h++) { + found = 0; + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + if (nnode->nbranch[i].nnode) { + found = 1; + nnode = nnode->nbranch[i].nnode; + *hght = h; + break; + } + } + if (!found) + break; + } + return nnode; +} + +/** + * next_nnode - find the next nnode in memory. + * @c: UBIFS file-system description object + * @nnode: nnode from which to start. + * @hght: height of tree where nnode is, is passed and returned here + * + * This function returns a pointer to the nnode found or %NULL if no nnode is + * found. This function is a helper to 'ubifs_lpt_free()'. + */ +static struct ubifs_nnode *next_nnode(struct ubifs_info *c, + struct ubifs_nnode *nnode, int *hght) +{ + struct ubifs_nnode *parent; + int iip, h, i, found; + + parent = nnode->parent; + if (!parent) + return NULL; + if (nnode->iip == UBIFS_LPT_FANOUT - 1) { + *hght -= 1; + return parent; + } + for (iip = nnode->iip + 1; iip < UBIFS_LPT_FANOUT; iip++) { + nnode = parent->nbranch[iip].nnode; + if (nnode) + break; + } + if (!nnode) { + *hght -= 1; + return parent; + } + for (h = *hght + 1; h < c->lpt_hght; h++) { + found = 0; + for (i = 0; i < UBIFS_LPT_FANOUT; i++) { + if (nnode->nbranch[i].nnode) { + found = 1; + nnode = nnode->nbranch[i].nnode; + *hght = h; + break; + } + } + if (!found) + break; + } + return nnode; +} + +/** + * ubifs_lpt_free - free resources owned by the LPT. + * @c: UBIFS file-system description object + * @wr_only: free only resources used for writing + */ +void ubifs_lpt_free(struct ubifs_info *c, int wr_only) +{ + struct ubifs_nnode *nnode; + int i, hght; + + /* Free write-only things first */ + + free_obsolete_cnodes(c); /* Leftover from a failed commit */ + + vfree(c->ltab_cmt); + c->ltab_cmt = NULL; + vfree(c->lpt_buf); + c->lpt_buf = NULL; + kfree(c->lsave); + c->lsave = NULL; + + if (wr_only) + return; + + /* Now free the rest */ + + nnode = first_nnode(c, &hght); + while (nnode) { + for (i = 0; i < UBIFS_LPT_FANOUT; i++) + kfree(nnode->nbranch[i].nnode); + nnode = next_nnode(c, nnode, &hght); + } + for (i = 0; i < LPROPS_HEAP_CNT; i++) + kfree(c->lpt_heap[i].arr); + kfree(c->dirty_idx.arr); + kfree(c->nroot); + vfree(c->ltab); + kfree(c->lpt_nod_buf); +} diff --git a/fs/ubifs/master.c b/fs/ubifs/master.c new file mode 100644 index 0000000..3f2926e --- /dev/null +++ b/fs/ubifs/master.c @@ -0,0 +1,341 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* This file implements reading and writing the master node */ + +#include "ubifs.h" + +/** + * scan_for_master - search the valid master node. + * @c: UBIFS file-system description object + * + * This function scans the master node LEBs and search for the latest master + * node. Returns zero in case of success and a negative error code in case of + * failure. + */ +static int scan_for_master(struct ubifs_info *c) +{ + struct ubifs_scan_leb *sleb; + struct ubifs_scan_node *snod; + int lnum, offs = 0, nodes_cnt; + + lnum = UBIFS_MST_LNUM; + + sleb = ubifs_scan(c, lnum, 0, c->sbuf); + if (IS_ERR(sleb)) + return PTR_ERR(sleb); + nodes_cnt = sleb->nodes_cnt; + if (nodes_cnt > 0) { + snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, + list); + if (snod->type != UBIFS_MST_NODE) + goto out; + memcpy(c->mst_node, snod->node, snod->len); + offs = snod->offs; + } + ubifs_scan_destroy(sleb); + + lnum += 1; + + sleb = ubifs_scan(c, lnum, 0, c->sbuf); + if (IS_ERR(sleb)) + return PTR_ERR(sleb); + if (sleb->nodes_cnt != nodes_cnt) + goto out; + if (!sleb->nodes_cnt) + goto out; + snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, list); + if (snod->type != UBIFS_MST_NODE) + goto out; + if (snod->offs != offs) + goto out; + if (memcmp((void *)c->mst_node + UBIFS_CH_SZ, + (void *)snod->node + UBIFS_CH_SZ, + UBIFS_MST_NODE_SZ - UBIFS_CH_SZ)) + goto out; + c->mst_offs = offs; + ubifs_scan_destroy(sleb); + return 0; + +out: + ubifs_scan_destroy(sleb); + return -EINVAL; +} + +/** + * validate_master - validate master node. + * @c: UBIFS file-system description object + * + * This function validates data which was read from master node. Returns zero + * if the data is all right and %-EINVAL if not. + */ +static int validate_master(const struct ubifs_info *c) +{ + long long main_sz; + int err; + + if (c->max_sqnum >= SQNUM_WATERMARK) { + err = 1; + goto out; + } + + if (c->cmt_no >= c->max_sqnum) { + err = 2; + goto out; + } + + if (c->highest_inum >= INUM_WATERMARK) { + err = 3; + goto out; + } + + if (c->lhead_lnum < UBIFS_LOG_LNUM || + c->lhead_lnum >= UBIFS_LOG_LNUM + c->log_lebs || + c->lhead_offs < 0 || c->lhead_offs >= c->leb_size || + c->lhead_offs & (c->min_io_size - 1)) { + err = 4; + goto out; + } + + if (c->zroot.lnum >= c->leb_cnt || c->zroot.lnum < c->main_first || + c->zroot.offs >= c->leb_size || c->zroot.offs & 7) { + err = 5; + goto out; + } + + if (c->zroot.len < c->ranges[UBIFS_IDX_NODE].min_len || + c->zroot.len > c->ranges[UBIFS_IDX_NODE].max_len) { + err = 6; + goto out; + } + + if (c->gc_lnum >= c->leb_cnt || c->gc_lnum < c->main_first) { + err = 7; + goto out; + } + + if (c->ihead_lnum >= c->leb_cnt || c->ihead_lnum < c->main_first || + c->ihead_offs % c->min_io_size || c->ihead_offs < 0 || + c->ihead_offs > c->leb_size || c->ihead_offs & 7) { + err = 8; + goto out; + } + + main_sz = (long long)c->main_lebs * c->leb_size; + if (c->old_idx_sz & 7 || c->old_idx_sz >= main_sz) { + err = 9; + goto out; + } + + if (c->lpt_lnum < c->lpt_first || c->lpt_lnum > c->lpt_last || + c->lpt_offs < 0 || c->lpt_offs + c->nnode_sz > c->leb_size) { + err = 10; + goto out; + } + + if (c->nhead_lnum < c->lpt_first || c->nhead_lnum > c->lpt_last || + c->nhead_offs < 0 || c->nhead_offs % c->min_io_size || + c->nhead_offs > c->leb_size) { + err = 11; + goto out; + } + + if (c->ltab_lnum < c->lpt_first || c->ltab_lnum > c->lpt_last || + c->ltab_offs < 0 || + c->ltab_offs + c->ltab_sz > c->leb_size) { + err = 12; + goto out; + } + + if (c->big_lpt && (c->lsave_lnum < c->lpt_first || + c->lsave_lnum > c->lpt_last || c->lsave_offs < 0 || + c->lsave_offs + c->lsave_sz > c->leb_size)) { + err = 13; + goto out; + } + + if (c->lscan_lnum < c->main_first || c->lscan_lnum >= c->leb_cnt) { + err = 14; + goto out; + } + + if (c->lst.empty_lebs < 0 || c->lst.empty_lebs > c->main_lebs - 2) { + err = 15; + goto out; + } + + if (c->lst.idx_lebs < 0 || c->lst.idx_lebs > c->main_lebs - 1) { + err = 16; + goto out; + } + + if (c->lst.total_free < 0 || c->lst.total_free > main_sz || + c->lst.total_free & 7) { + err = 17; + goto out; + } + + if (c->lst.total_dirty < 0 || (c->lst.total_dirty & 7)) { + err = 18; + goto out; + } + + if (c->lst.total_used < 0 || (c->lst.total_used & 7)) { + err = 19; + goto out; + } + + if (c->lst.total_free + c->lst.total_dirty + + c->lst.total_used > main_sz) { + err = 20; + goto out; + } + + if (c->lst.total_dead + c->lst.total_dark + + c->lst.total_used + c->old_idx_sz > main_sz) { + err = 21; + goto out; + } + + if (c->lst.total_dead < 0 || + c->lst.total_dead > c->lst.total_free + c->lst.total_dirty || + c->lst.total_dead & 7) { + err = 22; + goto out; + } + + if (c->lst.total_dark < 0 || + c->lst.total_dark > c->lst.total_free + c->lst.total_dirty || + c->lst.total_dark & 7) { + err = 23; + goto out; + } + + return 0; + +out: + ubifs_err("bad master node at offset %d error %d", c->mst_offs, err); + dbg_dump_node(c, c->mst_node); + return -EINVAL; +} + +/** + * ubifs_read_master - read master node. + * @c: UBIFS file-system description object + * + * This function finds and reads the master node during file-system mount. If + * the flash is empty, it creates default master node as well. Returns zero in + * case of success and a negative error code in case of failure. + */ +int ubifs_read_master(struct ubifs_info *c) +{ + int err, old_leb_cnt; + + c->mst_node = kzalloc(c->mst_node_alsz, GFP_KERNEL); + if (!c->mst_node) + return -ENOMEM; + + err = scan_for_master(c); + if (err) { + err = ubifs_recover_master_node(c); + if (err) + /* + * Note, we do not free 'c->mst_node' here because the + * unmount routine will take care of this. + */ + return err; + } + + /* Make sure that the recovery flag is clear */ + c->mst_node->flags &= cpu_to_le32(~UBIFS_MST_RCVRY); + + c->max_sqnum = le64_to_cpu(c->mst_node->ch.sqnum); + c->highest_inum = le64_to_cpu(c->mst_node->highest_inum); + c->cmt_no = le64_to_cpu(c->mst_node->cmt_no); + c->zroot.lnum = le32_to_cpu(c->mst_node->root_lnum); + c->zroot.offs = le32_to_cpu(c->mst_node->root_offs); + c->zroot.len = le32_to_cpu(c->mst_node->root_len); + c->lhead_lnum = le32_to_cpu(c->mst_node->log_lnum); + c->gc_lnum = le32_to_cpu(c->mst_node->gc_lnum); + c->ihead_lnum = le32_to_cpu(c->mst_node->ihead_lnum); + c->ihead_offs = le32_to_cpu(c->mst_node->ihead_offs); + c->old_idx_sz = le64_to_cpu(c->mst_node->index_size); + c->lpt_lnum = le32_to_cpu(c->mst_node->lpt_lnum); + c->lpt_offs = le32_to_cpu(c->mst_node->lpt_offs); + c->nhead_lnum = le32_to_cpu(c->mst_node->nhead_lnum); + c->nhead_offs = le32_to_cpu(c->mst_node->nhead_offs); + c->ltab_lnum = le32_to_cpu(c->mst_node->ltab_lnum); + c->ltab_offs = le32_to_cpu(c->mst_node->ltab_offs); + c->lsave_lnum = le32_to_cpu(c->mst_node->lsave_lnum); + c->lsave_offs = le32_to_cpu(c->mst_node->lsave_offs); + c->lscan_lnum = le32_to_cpu(c->mst_node->lscan_lnum); + c->lst.empty_lebs = le32_to_cpu(c->mst_node->empty_lebs); + c->lst.idx_lebs = le32_to_cpu(c->mst_node->idx_lebs); + old_leb_cnt = le32_to_cpu(c->mst_node->leb_cnt); + c->lst.total_free = le64_to_cpu(c->mst_node->total_free); + c->lst.total_dirty = le64_to_cpu(c->mst_node->total_dirty); + c->lst.total_used = le64_to_cpu(c->mst_node->total_used); + c->lst.total_dead = le64_to_cpu(c->mst_node->total_dead); + c->lst.total_dark = le64_to_cpu(c->mst_node->total_dark); + + c->calc_idx_sz = c->old_idx_sz; + + if (c->mst_node->flags & cpu_to_le32(UBIFS_MST_NO_ORPHS)) + c->no_orphs = 1; + + if (old_leb_cnt != c->leb_cnt) { + /* The file system has been resized */ + int growth = c->leb_cnt - old_leb_cnt; + + if (c->leb_cnt < old_leb_cnt || + c->leb_cnt < UBIFS_MIN_LEB_CNT) { + ubifs_err("bad leb_cnt on master node"); + dbg_dump_node(c, c->mst_node); + return -EINVAL; + } + + dbg_mnt("Auto resizing (master) from %d LEBs to %d LEBs", + old_leb_cnt, c->leb_cnt); + c->lst.empty_lebs += growth; + c->lst.total_free += growth * (long long)c->leb_size; + c->lst.total_dark += growth * (long long)c->dark_wm; + + /* + * Reflect changes back onto the master node. N.B. the master + * node gets written immediately whenever mounting (or + * remounting) in read-write mode, so we do not need to write it + * here. + */ + c->mst_node->leb_cnt = cpu_to_le32(c->leb_cnt); + c->mst_node->empty_lebs = cpu_to_le32(c->lst.empty_lebs); + c->mst_node->total_free = cpu_to_le64(c->lst.total_free); + c->mst_node->total_dark = cpu_to_le64(c->lst.total_dark); + } + + err = validate_master(c); + if (err) + return err; + + err = dbg_old_index_check_init(c, &c->zroot); + + return err; +} diff --git a/fs/ubifs/misc.h b/fs/ubifs/misc.h new file mode 100644 index 0000000..b745d86 --- /dev/null +++ b/fs/ubifs/misc.h @@ -0,0 +1,310 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file contains miscellaneous helper functions. + */ + +#ifndef __UBIFS_MISC_H__ +#define __UBIFS_MISC_H__ + +/** + * ubifs_zn_dirty - check if znode is dirty. + * @znode: znode to check + * + * This helper function returns %1 if @znode is dirty and %0 otherwise. + */ +static inline int ubifs_zn_dirty(const struct ubifs_znode *znode) +{ + return !!test_bit(DIRTY_ZNODE, &znode->flags); +} + +/** + * ubifs_wake_up_bgt - wake up background thread. + * @c: UBIFS file-system description object + */ +static inline void ubifs_wake_up_bgt(struct ubifs_info *c) +{ + if (c->bgt && !c->need_bgt) { + c->need_bgt = 1; + wake_up_process(c->bgt); + } +} + +/** + * ubifs_tnc_find_child - find next child in znode. + * @znode: znode to search at + * @start: the zbranch index to start at + * + * This helper function looks for znode child starting at index @start. Returns + * the child or %NULL if no children were found. + */ +static inline struct ubifs_znode * +ubifs_tnc_find_child(struct ubifs_znode *znode, int start) +{ + while (start < znode->child_cnt) { + if (znode->zbranch[start].znode) + return znode->zbranch[start].znode; + start += 1; + } + + return NULL; +} + +/** + * ubifs_inode - get UBIFS inode information by VFS 'struct inode' object. + * @inode: the VFS 'struct inode' pointer + */ +static inline struct ubifs_inode *ubifs_inode(const struct inode *inode) +{ + return container_of(inode, struct ubifs_inode, vfs_inode); +} + +/** + * ubifs_compr_present - check if compressor was compiled in. + * @compr_type: compressor type to check + * + * This function returns %1 of compressor of type @compr_type is present, and + * %0 if not. + */ +static inline int ubifs_compr_present(int compr_type) +{ + ubifs_assert(compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT); + return !!ubifs_compressors[compr_type]->capi_name; +} + +/** + * ubifs_compr_name - get compressor name string by its type. + * @compr_type: compressor type + * + * This function returns compressor type string. + */ +static inline const char *ubifs_compr_name(int compr_type) +{ + ubifs_assert(compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT); + return ubifs_compressors[compr_type]->name; +} + +/** + * ubifs_wbuf_sync - synchronize write-buffer. + * @wbuf: write-buffer to synchronize + * + * This is the same as as 'ubifs_wbuf_sync_nolock()' but it does not assume + * that the write-buffer is already locked. + */ +static inline int ubifs_wbuf_sync(struct ubifs_wbuf *wbuf) +{ + int err; + + mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead); + err = ubifs_wbuf_sync_nolock(wbuf); + mutex_unlock(&wbuf->io_mutex); + return err; +} + +/** + * ubifs_leb_unmap - unmap an LEB. + * @c: UBIFS file-system description object + * @lnum: LEB number to unmap + * + * This function returns %0 on success and a negative error code on failure. + */ +static inline int ubifs_leb_unmap(const struct ubifs_info *c, int lnum) +{ + int err; + + if (c->ro_media) + return -EROFS; + err = ubi_leb_unmap(c->ubi, lnum); + if (err) { + ubifs_err("unmap LEB %d failed, error %d", lnum, err); + return err; + } + + return 0; +} + +/** + * ubifs_leb_write - write to a LEB. + * @c: UBIFS file-system description object + * @lnum: LEB number to write + * @buf: buffer to write from + * @offs: offset within LEB to write to + * @len: length to write + * @dtype: data type + * + * This function returns %0 on success and a negative error code on failure. + */ +static inline int ubifs_leb_write(const struct ubifs_info *c, int lnum, + const void *buf, int offs, int len, int dtype) +{ + int err; + + if (c->ro_media) + return -EROFS; + err = ubi_leb_write(c->ubi, lnum, buf, offs, len, dtype); + if (err) { + ubifs_err("writing %d bytes at %d:%d, error %d", + len, lnum, offs, err); + return err; + } + + return 0; +} + +/** + * ubifs_leb_change - atomic LEB change. + * @c: UBIFS file-system description object + * @lnum: LEB number to write + * @buf: buffer to write from + * @len: length to write + * @dtype: data type + * + * This function returns %0 on success and a negative error code on failure. + */ +static inline int ubifs_leb_change(const struct ubifs_info *c, int lnum, + const void *buf, int len, int dtype) +{ + int err; + + if (c->ro_media) + return -EROFS; + err = ubi_leb_change(c->ubi, lnum, buf, len, dtype); + if (err) { + ubifs_err("changing %d bytes in LEB %d, error %d", + len, lnum, err); + return err; + } + + return 0; +} + +/** + * ubifs_add_dirt - add dirty space to LEB properties. + * @c: the UBIFS file-system description object + * @lnum: LEB to add dirty space for + * @dirty: dirty space to add + * + * This is a helper function which increased amount of dirty LEB space. Returns + * zero in case of success and a negative error code in case of failure. + */ +static inline int ubifs_add_dirt(struct ubifs_info *c, int lnum, int dirty) +{ + return ubifs_update_one_lp(c, lnum, LPROPS_NC, dirty, 0, 0); +} + +/** + * ubifs_return_leb - return LEB to lprops. + * @c: the UBIFS file-system description object + * @lnum: LEB to return + * + * This helper function cleans the "taken" flag of a logical eraseblock in the + * lprops. Returns zero in case of success and a negative error code in case of + * failure. + */ +static inline int ubifs_return_leb(struct ubifs_info *c, int lnum) +{ + return ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0, + LPROPS_TAKEN, 0); +} + +/** + * ubifs_idx_node_sz - return index node size. + * @c: the UBIFS file-system description object + * @child_cnt: number of children of this index node + */ +static inline int ubifs_idx_node_sz(const struct ubifs_info *c, int child_cnt) +{ + return UBIFS_IDX_NODE_SZ + (UBIFS_BRANCH_SZ + c->key_len) * child_cnt; +} + +/** + * ubifs_idx_branch - return pointer to an index branch. + * @c: the UBIFS file-system description object + * @idx: index node + * @bnum: branch number + */ +static inline +struct ubifs_branch *ubifs_idx_branch(const struct ubifs_info *c, + const struct ubifs_idx_node *idx, + int bnum) +{ + return (struct ubifs_branch *)((void *)idx->branches + + (UBIFS_BRANCH_SZ + c->key_len) * bnum); +} + +/** + * ubifs_idx_key - return pointer to an index key. + * @c: the UBIFS file-system description object + * @idx: index node + */ +static inline void *ubifs_idx_key(const struct ubifs_info *c, + const struct ubifs_idx_node *idx) +{ + return (void *)((struct ubifs_branch *)idx->branches)->key; +} + +/** + * ubifs_tnc_lookup - look up a file-system node. + * @c: UBIFS file-system description object + * @key: node key to lookup + * @node: the node is returned here + * + * This function look up and reads node with key @key. The caller has to make + * sure the @node buffer is large enough to fit the node. Returns zero in case + * of success, %-ENOENT if the node was not found, and a negative error code in + * case of failure. + */ +static inline int ubifs_tnc_lookup(struct ubifs_info *c, + const union ubifs_key *key, void *node) +{ + return ubifs_tnc_locate(c, key, node, NULL, NULL); +} + +/** + * ubifs_get_lprops - get reference to LEB properties. + * @c: the UBIFS file-system description object + * + * This function locks lprops. Lprops have to be unlocked by + * 'ubifs_release_lprops()'. + */ +static inline void ubifs_get_lprops(struct ubifs_info *c) +{ + mutex_lock(&c->lp_mutex); +} + +/** + * ubifs_release_lprops - release lprops lock. + * @c: the UBIFS file-system description object + * + * This function has to be called after each 'ubifs_get_lprops()' call to + * unlock lprops. + */ +static inline void ubifs_release_lprops(struct ubifs_info *c) +{ + ubifs_assert(mutex_is_locked(&c->lp_mutex)); + ubifs_assert(c->lst.empty_lebs >= 0 && + c->lst.empty_lebs <= c->main_lebs); + mutex_unlock(&c->lp_mutex); +} + +#endif /* __UBIFS_MISC_H__ */ diff --git a/fs/ubifs/orphan.c b/fs/ubifs/orphan.c new file mode 100644 index 0000000..d091031 --- /dev/null +++ b/fs/ubifs/orphan.c @@ -0,0 +1,316 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Author: Adrian Hunter + */ + +#include "ubifs.h" + +/* + * An orphan is an inode number whose inode node has been committed to the index + * with a link count of zero. That happens when an open file is deleted + * (unlinked) and then a commit is run. In the normal course of events the inode + * would be deleted when the file is closed. However in the case of an unclean + * unmount, orphans need to be accounted for. After an unclean unmount, the + * orphans' inodes must be deleted which means either scanning the entire index + * looking for them, or keeping a list on flash somewhere. This unit implements + * the latter approach. + * + * The orphan area is a fixed number of LEBs situated between the LPT area and + * the main area. The number of orphan area LEBs is specified when the file + * system is created. The minimum number is 1. The size of the orphan area + * should be so that it can hold the maximum number of orphans that are expected + * to ever exist at one time. + * + * The number of orphans that can fit in a LEB is: + * + * (c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64) + * + * For example: a 15872 byte LEB can fit 1980 orphans so 1 LEB may be enough. + * + * Orphans are accumulated in a rb-tree. When an inode's link count drops to + * zero, the inode number is added to the rb-tree. It is removed from the tree + * when the inode is deleted. Any new orphans that are in the orphan tree when + * the commit is run, are written to the orphan area in 1 or more orphan nodes. + * If the orphan area is full, it is consolidated to make space. There is + * always enough space because validation prevents the user from creating more + * than the maximum number of orphans allowed. + */ + +/** + * tot_avail_orphs - calculate total space. + * @c: UBIFS file-system description object + * + * This function returns the number of orphans that can be written in half + * the total space. That leaves half the space for adding new orphans. + */ +static int tot_avail_orphs(struct ubifs_info *c) +{ + int avail_lebs, avail; + + avail_lebs = c->orph_lebs; + avail = avail_lebs * + ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64)); + return avail / 2; +} + +/** + * ubifs_clear_orphans - erase all LEBs used for orphans. + * @c: UBIFS file-system description object + * + * If recovery is not required, then the orphans from the previous session + * are not needed. This function locates the LEBs used to record + * orphans, and un-maps them. + */ +int ubifs_clear_orphans(struct ubifs_info *c) +{ + int lnum, err; + + for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) { + err = ubifs_leb_unmap(c, lnum); + if (err) + return err; + } + c->ohead_lnum = c->orph_first; + c->ohead_offs = 0; + return 0; +} + +/** + * insert_dead_orphan - insert an orphan. + * @c: UBIFS file-system description object + * @inum: orphan inode number + * + * This function is a helper to the 'do_kill_orphans()' function. The orphan + * must be kept until the next commit, so it is added to the rb-tree and the + * deletion list. + */ +static int insert_dead_orphan(struct ubifs_info *c, ino_t inum) +{ + struct ubifs_orphan *orphan, *o; + struct rb_node **p, *parent = NULL; + + orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_KERNEL); + if (!orphan) + return -ENOMEM; + orphan->inum = inum; + + p = &c->orph_tree.rb_node; + while (*p) { + parent = *p; + o = rb_entry(parent, struct ubifs_orphan, rb); + if (inum < o->inum) + p = &(*p)->rb_left; + else if (inum > o->inum) + p = &(*p)->rb_right; + else { + /* Already added - no problem */ + kfree(orphan); + return 0; + } + } + c->tot_orphans += 1; + rb_link_node(&orphan->rb, parent, p); + rb_insert_color(&orphan->rb, &c->orph_tree); + list_add_tail(&orphan->list, &c->orph_list); + orphan->dnext = c->orph_dnext; + c->orph_dnext = orphan; + dbg_mnt("ino %lu, new %d, tot %d", (unsigned long)inum, + c->new_orphans, c->tot_orphans); + return 0; +} + +/** + * do_kill_orphans - remove orphan inodes from the index. + * @c: UBIFS file-system description object + * @sleb: scanned LEB + * @last_cmt_no: cmt_no of last orphan node read is passed and returned here + * @outofdate: whether the LEB is out of date is returned here + * @last_flagged: whether the end orphan node is encountered + * + * This function is a helper to the 'kill_orphans()' function. It goes through + * every orphan node in a LEB and for every inode number recorded, removes + * all keys for that inode from the TNC. + */ +static int do_kill_orphans(struct ubifs_info *c, struct ubifs_scan_leb *sleb, + unsigned long long *last_cmt_no, int *outofdate, + int *last_flagged) +{ + struct ubifs_scan_node *snod; + struct ubifs_orph_node *orph; + unsigned long long cmt_no; + ino_t inum; + int i, n, err, first = 1; + + list_for_each_entry(snod, &sleb->nodes, list) { + if (snod->type != UBIFS_ORPH_NODE) { + ubifs_err("invalid node type %d in orphan area at " + "%d:%d", snod->type, sleb->lnum, snod->offs); + dbg_dump_node(c, snod->node); + return -EINVAL; + } + + orph = snod->node; + + /* Check commit number */ + cmt_no = le64_to_cpu(orph->cmt_no) & LLONG_MAX; + /* + * The commit number on the master node may be less, because + * of a failed commit. If there are several failed commits in a + * row, the commit number written on orphan nodes will continue + * to increase (because the commit number is adjusted here) even + * though the commit number on the master node stays the same + * because the master node has not been re-written. + */ + if (cmt_no > c->cmt_no) + c->cmt_no = cmt_no; + if (cmt_no < *last_cmt_no && *last_flagged) { + /* + * The last orphan node had a higher commit number and + * was flagged as the last written for that commit + * number. That makes this orphan node, out of date. + */ + if (!first) { + ubifs_err("out of order commit number %llu in " + "orphan node at %d:%d", + cmt_no, sleb->lnum, snod->offs); + dbg_dump_node(c, snod->node); + return -EINVAL; + } + dbg_rcvry("out of date LEB %d", sleb->lnum); + *outofdate = 1; + return 0; + } + + if (first) + first = 0; + + n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3; + for (i = 0; i < n; i++) { + inum = le64_to_cpu(orph->inos[i]); + dbg_rcvry("deleting orphaned inode %lu", + (unsigned long)inum); + err = ubifs_tnc_remove_ino(c, inum); + if (err) + return err; + err = insert_dead_orphan(c, inum); + if (err) + return err; + } + + *last_cmt_no = cmt_no; + if (le64_to_cpu(orph->cmt_no) & (1ULL << 63)) { + dbg_rcvry("last orph node for commit %llu at %d:%d", + cmt_no, sleb->lnum, snod->offs); + *last_flagged = 1; + } else + *last_flagged = 0; + } + + return 0; +} + +/** + * kill_orphans - remove all orphan inodes from the index. + * @c: UBIFS file-system description object + * + * If recovery is required, then orphan inodes recorded during the previous + * session (which ended with an unclean unmount) must be deleted from the index. + * This is done by updating the TNC, but since the index is not updated until + * the next commit, the LEBs where the orphan information is recorded are not + * erased until the next commit. + */ +static int kill_orphans(struct ubifs_info *c) +{ + unsigned long long last_cmt_no = 0; + int lnum, err = 0, outofdate = 0, last_flagged = 0; + + c->ohead_lnum = c->orph_first; + c->ohead_offs = 0; + /* Check no-orphans flag and skip this if no orphans */ + if (c->no_orphs) { + dbg_rcvry("no orphans"); + return 0; + } + /* + * Orph nodes always start at c->orph_first and are written to each + * successive LEB in turn. Generally unused LEBs will have been unmapped + * but may contain out of date orphan nodes if the unmap didn't go + * through. In addition, the last orphan node written for each commit is + * marked (top bit of orph->cmt_no is set to 1). It is possible that + * there are orphan nodes from the next commit (i.e. the commit did not + * complete successfully). In that case, no orphans will have been lost + * due to the way that orphans are written, and any orphans added will + * be valid orphans anyway and so can be deleted. + */ + for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) { + struct ubifs_scan_leb *sleb; + + dbg_rcvry("LEB %d", lnum); + sleb = ubifs_scan(c, lnum, 0, c->sbuf); + if (IS_ERR(sleb)) { + sleb = ubifs_recover_leb(c, lnum, 0, c->sbuf, 0); + if (IS_ERR(sleb)) { + err = PTR_ERR(sleb); + break; + } + } + err = do_kill_orphans(c, sleb, &last_cmt_no, &outofdate, + &last_flagged); + if (err || outofdate) { + ubifs_scan_destroy(sleb); + break; + } + if (sleb->endpt) { + c->ohead_lnum = lnum; + c->ohead_offs = sleb->endpt; + } + ubifs_scan_destroy(sleb); + } + return err; +} + +/** + * ubifs_mount_orphans - delete orphan inodes and erase LEBs that recorded them. + * @c: UBIFS file-system description object + * @unclean: indicates recovery from unclean unmount + * @read_only: indicates read only mount + * + * This function is called when mounting to erase orphans from the previous + * session. If UBIFS was not unmounted cleanly, then the inodes recorded as + * orphans are deleted. + */ +int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only) +{ + int err = 0; + + c->max_orphans = tot_avail_orphs(c); + + if (!read_only) { + c->orph_buf = vmalloc(c->leb_size); + if (!c->orph_buf) + return -ENOMEM; + } + + if (unclean) + err = kill_orphans(c); + else if (!read_only) + err = ubifs_clear_orphans(c); + + return err; +} diff --git a/fs/ubifs/recovery.c b/fs/ubifs/recovery.c new file mode 100644 index 0000000..fe3b364 --- /dev/null +++ b/fs/ubifs/recovery.c @@ -0,0 +1,1249 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements functions needed to recover from unclean un-mounts. + * When UBIFS is mounted, it checks a flag on the master node to determine if + * an un-mount was completed sucessfully. If not, the process of mounting + * incorparates additional checking and fixing of on-flash data structures. + * UBIFS always cleans away all remnants of an unclean un-mount, so that + * errors do not accumulate. However UBIFS defers recovery if it is mounted + * read-only, and the flash is not modified in that case. + */ + +#include "ubifs.h" + +/** + * is_empty - determine whether a buffer is empty (contains all 0xff). + * @buf: buffer to clean + * @len: length of buffer + * + * This function returns %1 if the buffer is empty (contains all 0xff) otherwise + * %0 is returned. + */ +static int is_empty(void *buf, int len) +{ + uint8_t *p = buf; + int i; + + for (i = 0; i < len; i++) + if (*p++ != 0xff) + return 0; + return 1; +} + +/** + * get_master_node - get the last valid master node allowing for corruption. + * @c: UBIFS file-system description object + * @lnum: LEB number + * @pbuf: buffer containing the LEB read, is returned here + * @mst: master node, if found, is returned here + * @cor: corruption, if found, is returned here + * + * This function allocates a buffer, reads the LEB into it, and finds and + * returns the last valid master node allowing for one area of corruption. + * The corrupt area, if there is one, must be consistent with the assumption + * that it is the result of an unclean unmount while the master node was being + * written. Under those circumstances, it is valid to use the previously written + * master node. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int get_master_node(const struct ubifs_info *c, int lnum, void **pbuf, + struct ubifs_mst_node **mst, void **cor) +{ + const int sz = c->mst_node_alsz; + int err, offs, len; + void *sbuf, *buf; + + sbuf = vmalloc(c->leb_size); + if (!sbuf) + return -ENOMEM; + + err = ubi_read(c->ubi, lnum, sbuf, 0, c->leb_size); + if (err && err != -EBADMSG) + goto out_free; + + /* Find the first position that is definitely not a node */ + offs = 0; + buf = sbuf; + len = c->leb_size; + while (offs + UBIFS_MST_NODE_SZ <= c->leb_size) { + struct ubifs_ch *ch = buf; + + if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC) + break; + offs += sz; + buf += sz; + len -= sz; + } + /* See if there was a valid master node before that */ + if (offs) { + int ret; + + offs -= sz; + buf -= sz; + len += sz; + ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1); + if (ret != SCANNED_A_NODE && offs) { + /* Could have been corruption so check one place back */ + offs -= sz; + buf -= sz; + len += sz; + ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1); + if (ret != SCANNED_A_NODE) + /* + * We accept only one area of corruption because + * we are assuming that it was caused while + * trying to write a master node. + */ + goto out_err; + } + if (ret == SCANNED_A_NODE) { + struct ubifs_ch *ch = buf; + + if (ch->node_type != UBIFS_MST_NODE) + goto out_err; + dbg_rcvry("found a master node at %d:%d", lnum, offs); + *mst = buf; + offs += sz; + buf += sz; + len -= sz; + } + } + /* Check for corruption */ + if (offs < c->leb_size) { + if (!is_empty(buf, min_t(int, len, sz))) { + *cor = buf; + dbg_rcvry("found corruption at %d:%d", lnum, offs); + } + offs += sz; + buf += sz; + len -= sz; + } + /* Check remaining empty space */ + if (offs < c->leb_size) + if (!is_empty(buf, len)) + goto out_err; + *pbuf = sbuf; + return 0; + +out_err: + err = -EINVAL; +out_free: + vfree(sbuf); + *mst = NULL; + *cor = NULL; + return err; +} + +/** + * write_rcvrd_mst_node - write recovered master node. + * @c: UBIFS file-system description object + * @mst: master node + * + * This function returns %0 on success and a negative error code on failure. + */ +static int write_rcvrd_mst_node(struct ubifs_info *c, + struct ubifs_mst_node *mst) +{ + int err = 0, lnum = UBIFS_MST_LNUM, sz = c->mst_node_alsz; + __le32 save_flags; + + dbg_rcvry("recovery"); + + save_flags = mst->flags; + mst->flags |= cpu_to_le32(UBIFS_MST_RCVRY); + + ubifs_prepare_node(c, mst, UBIFS_MST_NODE_SZ, 1); + err = ubi_leb_change(c->ubi, lnum, mst, sz, UBI_SHORTTERM); + if (err) + goto out; + err = ubi_leb_change(c->ubi, lnum + 1, mst, sz, UBI_SHORTTERM); + if (err) + goto out; +out: + mst->flags = save_flags; + return err; +} + +/** + * ubifs_recover_master_node - recover the master node. + * @c: UBIFS file-system description object + * + * This function recovers the master node from corruption that may occur due to + * an unclean unmount. + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_recover_master_node(struct ubifs_info *c) +{ + void *buf1 = NULL, *buf2 = NULL, *cor1 = NULL, *cor2 = NULL; + struct ubifs_mst_node *mst1 = NULL, *mst2 = NULL, *mst; + const int sz = c->mst_node_alsz; + int err, offs1, offs2; + + dbg_rcvry("recovery"); + + err = get_master_node(c, UBIFS_MST_LNUM, &buf1, &mst1, &cor1); + if (err) + goto out_free; + + err = get_master_node(c, UBIFS_MST_LNUM + 1, &buf2, &mst2, &cor2); + if (err) + goto out_free; + + if (mst1) { + offs1 = (void *)mst1 - buf1; + if ((le32_to_cpu(mst1->flags) & UBIFS_MST_RCVRY) && + (offs1 == 0 && !cor1)) { + /* + * mst1 was written by recovery at offset 0 with no + * corruption. + */ + dbg_rcvry("recovery recovery"); + mst = mst1; + } else if (mst2) { + offs2 = (void *)mst2 - buf2; + if (offs1 == offs2) { + /* Same offset, so must be the same */ + if (memcmp((void *)mst1 + UBIFS_CH_SZ, + (void *)mst2 + UBIFS_CH_SZ, + UBIFS_MST_NODE_SZ - UBIFS_CH_SZ)) + goto out_err; + mst = mst1; + } else if (offs2 + sz == offs1) { + /* 1st LEB was written, 2nd was not */ + if (cor1) + goto out_err; + mst = mst1; + } else if (offs1 == 0 && offs2 + sz >= c->leb_size) { + /* 1st LEB was unmapped and written, 2nd not */ + if (cor1) + goto out_err; + mst = mst1; + } else + goto out_err; + } else { + /* + * 2nd LEB was unmapped and about to be written, so + * there must be only one master node in the first LEB + * and no corruption. + */ + if (offs1 != 0 || cor1) + goto out_err; + mst = mst1; + } + } else { + if (!mst2) + goto out_err; + /* + * 1st LEB was unmapped and about to be written, so there must + * be no room left in 2nd LEB. + */ + offs2 = (void *)mst2 - buf2; + if (offs2 + sz + sz <= c->leb_size) + goto out_err; + mst = mst2; + } + + dbg_rcvry("recovered master node from LEB %d", + (mst == mst1 ? UBIFS_MST_LNUM : UBIFS_MST_LNUM + 1)); + + memcpy(c->mst_node, mst, UBIFS_MST_NODE_SZ); + + if ((c->vfs_sb->s_flags & MS_RDONLY)) { + /* Read-only mode. Keep a copy for switching to rw mode */ + c->rcvrd_mst_node = kmalloc(sz, GFP_KERNEL); + if (!c->rcvrd_mst_node) { + err = -ENOMEM; + goto out_free; + } + memcpy(c->rcvrd_mst_node, c->mst_node, UBIFS_MST_NODE_SZ); + } + + vfree(buf2); + vfree(buf1); + + return 0; + +out_err: + err = -EINVAL; +out_free: + ubifs_err("failed to recover master node"); + if (mst1) { + dbg_err("dumping first master node"); + dbg_dump_node(c, mst1); + } + if (mst2) { + dbg_err("dumping second master node"); + dbg_dump_node(c, mst2); + } + vfree(buf2); + vfree(buf1); + return err; +} + +/** + * ubifs_write_rcvrd_mst_node - write the recovered master node. + * @c: UBIFS file-system description object + * + * This function writes the master node that was recovered during mounting in + * read-only mode and must now be written because we are remounting rw. + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_write_rcvrd_mst_node(struct ubifs_info *c) +{ + int err; + + if (!c->rcvrd_mst_node) + return 0; + c->rcvrd_mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY); + c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY); + err = write_rcvrd_mst_node(c, c->rcvrd_mst_node); + if (err) + return err; + kfree(c->rcvrd_mst_node); + c->rcvrd_mst_node = NULL; + return 0; +} + +/** + * is_last_write - determine if an offset was in the last write to a LEB. + * @c: UBIFS file-system description object + * @buf: buffer to check + * @offs: offset to check + * + * This function returns %1 if @offs was in the last write to the LEB whose data + * is in @buf, otherwise %0 is returned. The determination is made by checking + * for subsequent empty space starting from the next min_io_size boundary (or a + * bit less than the common header size if min_io_size is one). + */ +static int is_last_write(const struct ubifs_info *c, void *buf, int offs) +{ + int empty_offs; + int check_len; + uint8_t *p; + + if (c->min_io_size == 1) { + check_len = c->leb_size - offs; + p = buf + check_len; + for (; check_len > 0; check_len--) + if (*--p != 0xff) + break; + /* + * 'check_len' is the size of the corruption which cannot be + * more than the size of 1 node if it was caused by an unclean + * unmount. + */ + if (check_len > UBIFS_MAX_NODE_SZ) + return 0; + return 1; + } + + /* + * Round up to the next c->min_io_size boundary i.e. 'offs' is in the + * last wbuf written. After that should be empty space. + */ + empty_offs = ALIGN(offs + 1, c->min_io_size); + check_len = c->leb_size - empty_offs; + p = buf + empty_offs - offs; + + for (; check_len > 0; check_len--) + if (*p++ != 0xff) + return 0; + return 1; +} + +/** + * clean_buf - clean the data from an LEB sitting in a buffer. + * @c: UBIFS file-system description object + * @buf: buffer to clean + * @lnum: LEB number to clean + * @offs: offset from which to clean + * @len: length of buffer + * + * This function pads up to the next min_io_size boundary (if there is one) and + * sets empty space to all 0xff. @buf, @offs and @len are updated to the next + * min_io_size boundary (if there is one). + */ +static void clean_buf(const struct ubifs_info *c, void **buf, int lnum, + int *offs, int *len) +{ + int empty_offs, pad_len; + + lnum = lnum; + dbg_rcvry("cleaning corruption at %d:%d", lnum, *offs); + + if (c->min_io_size == 1) { + memset(*buf, 0xff, c->leb_size - *offs); + return; + } + + ubifs_assert(!(*offs & 7)); + empty_offs = ALIGN(*offs, c->min_io_size); + pad_len = empty_offs - *offs; + ubifs_pad(c, *buf, pad_len); + *offs += pad_len; + *buf += pad_len; + *len -= pad_len; + memset(*buf, 0xff, c->leb_size - empty_offs); +} + +/** + * no_more_nodes - determine if there are no more nodes in a buffer. + * @c: UBIFS file-system description object + * @buf: buffer to check + * @len: length of buffer + * @lnum: LEB number of the LEB from which @buf was read + * @offs: offset from which @buf was read + * + * This function scans @buf for more nodes and returns %0 is a node is found and + * %1 if no more nodes are found. + */ +static int no_more_nodes(const struct ubifs_info *c, void *buf, int len, + int lnum, int offs) +{ + int skip, next_offs = 0; + + if (len > UBIFS_DATA_NODE_SZ) { + struct ubifs_ch *ch = buf; + int dlen = le32_to_cpu(ch->len); + + if (ch->node_type == UBIFS_DATA_NODE && dlen >= UBIFS_CH_SZ && + dlen <= UBIFS_MAX_DATA_NODE_SZ) + /* The corrupt node looks like a data node */ + next_offs = ALIGN(offs + dlen, 8); + } + + if (c->min_io_size == 1) + skip = 8; + else + skip = ALIGN(offs + 1, c->min_io_size) - offs; + + offs += skip; + buf += skip; + len -= skip; + while (len > 8) { + struct ubifs_ch *ch = buf; + uint32_t magic = le32_to_cpu(ch->magic); + int ret; + + if (magic == UBIFS_NODE_MAGIC) { + ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1); + if (ret == SCANNED_A_NODE || ret > 0) { + /* + * There is a small chance this is just data in + * a data node, so check that possibility. e.g. + * this is part of a file that itself contains + * a UBIFS image. + */ + if (next_offs && offs + le32_to_cpu(ch->len) <= + next_offs) + continue; + dbg_rcvry("unexpected node at %d:%d", lnum, + offs); + return 0; + } + } + offs += 8; + buf += 8; + len -= 8; + } + return 1; +} + +/** + * fix_unclean_leb - fix an unclean LEB. + * @c: UBIFS file-system description object + * @sleb: scanned LEB information + * @start: offset where scan started + */ +static int fix_unclean_leb(struct ubifs_info *c, struct ubifs_scan_leb *sleb, + int start) +{ + int lnum = sleb->lnum, endpt = start; + + /* Get the end offset of the last node we are keeping */ + if (!list_empty(&sleb->nodes)) { + struct ubifs_scan_node *snod; + + snod = list_entry(sleb->nodes.prev, + struct ubifs_scan_node, list); + endpt = snod->offs + snod->len; + } + + if ((c->vfs_sb->s_flags & MS_RDONLY) && !c->remounting_rw) { + /* Add to recovery list */ + struct ubifs_unclean_leb *ucleb; + + dbg_rcvry("need to fix LEB %d start %d endpt %d", + lnum, start, sleb->endpt); + ucleb = kzalloc(sizeof(struct ubifs_unclean_leb), GFP_NOFS); + if (!ucleb) + return -ENOMEM; + ucleb->lnum = lnum; + ucleb->endpt = endpt; + list_add_tail(&ucleb->list, &c->unclean_leb_list); + } + return 0; +} + +/** + * drop_incomplete_group - drop nodes from an incomplete group. + * @sleb: scanned LEB information + * @offs: offset of dropped nodes is returned here + * + * This function returns %1 if nodes are dropped and %0 otherwise. + */ +static int drop_incomplete_group(struct ubifs_scan_leb *sleb, int *offs) +{ + int dropped = 0; + + while (!list_empty(&sleb->nodes)) { + struct ubifs_scan_node *snod; + struct ubifs_ch *ch; + + snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, + list); + ch = snod->node; + if (ch->group_type != UBIFS_IN_NODE_GROUP) + return dropped; + dbg_rcvry("dropping node at %d:%d", sleb->lnum, snod->offs); + *offs = snod->offs; + list_del(&snod->list); + kfree(snod); + sleb->nodes_cnt -= 1; + dropped = 1; + } + return dropped; +} + +/** + * ubifs_recover_leb - scan and recover a LEB. + * @c: UBIFS file-system description object + * @lnum: LEB number + * @offs: offset + * @sbuf: LEB-sized buffer to use + * @grouped: nodes may be grouped for recovery + * + * This function does a scan of a LEB, but caters for errors that might have + * been caused by the unclean unmount from which we are attempting to recover. + * + * This function returns %0 on success and a negative error code on failure. + */ +struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum, + int offs, void *sbuf, int grouped) +{ + int err, len = c->leb_size - offs, need_clean = 0, quiet = 1; + int empty_chkd = 0, start = offs; + struct ubifs_scan_leb *sleb; + void *buf = sbuf + offs; + + dbg_rcvry("%d:%d", lnum, offs); + + sleb = ubifs_start_scan(c, lnum, offs, sbuf); + if (IS_ERR(sleb)) + return sleb; + + if (sleb->ecc) + need_clean = 1; + + while (len >= 8) { + int ret; + + dbg_scan("look at LEB %d:%d (%d bytes left)", + lnum, offs, len); + + cond_resched(); + + /* + * Scan quietly until there is an error from which we cannot + * recover + */ + ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet); + + if (ret == SCANNED_A_NODE) { + /* A valid node, and not a padding node */ + struct ubifs_ch *ch = buf; + int node_len; + + err = ubifs_add_snod(c, sleb, buf, offs); + if (err) + goto error; + node_len = ALIGN(le32_to_cpu(ch->len), 8); + offs += node_len; + buf += node_len; + len -= node_len; + continue; + } + + if (ret > 0) { + /* Padding bytes or a valid padding node */ + offs += ret; + buf += ret; + len -= ret; + continue; + } + + if (ret == SCANNED_EMPTY_SPACE) { + if (!is_empty(buf, len)) { + if (!is_last_write(c, buf, offs)) + break; + clean_buf(c, &buf, lnum, &offs, &len); + need_clean = 1; + } + empty_chkd = 1; + break; + } + + if (ret == SCANNED_GARBAGE || ret == SCANNED_A_BAD_PAD_NODE) + if (is_last_write(c, buf, offs)) { + clean_buf(c, &buf, lnum, &offs, &len); + need_clean = 1; + empty_chkd = 1; + break; + } + + if (ret == SCANNED_A_CORRUPT_NODE) + if (no_more_nodes(c, buf, len, lnum, offs)) { + clean_buf(c, &buf, lnum, &offs, &len); + need_clean = 1; + empty_chkd = 1; + break; + } + + if (quiet) { + /* Redo the last scan but noisily */ + quiet = 0; + continue; + } + + switch (ret) { + case SCANNED_GARBAGE: + dbg_err("garbage"); + goto corrupted; + case SCANNED_A_CORRUPT_NODE: + case SCANNED_A_BAD_PAD_NODE: + dbg_err("bad node"); + goto corrupted; + default: + dbg_err("unknown"); + goto corrupted; + } + } + + if (!empty_chkd && !is_empty(buf, len)) { + if (is_last_write(c, buf, offs)) { + clean_buf(c, &buf, lnum, &offs, &len); + need_clean = 1; + } else { + ubifs_err("corrupt empty space at LEB %d:%d", + lnum, offs); + goto corrupted; + } + } + + /* Drop nodes from incomplete group */ + if (grouped && drop_incomplete_group(sleb, &offs)) { + buf = sbuf + offs; + len = c->leb_size - offs; + clean_buf(c, &buf, lnum, &offs, &len); + need_clean = 1; + } + + if (offs % c->min_io_size) { + clean_buf(c, &buf, lnum, &offs, &len); + need_clean = 1; + } + + ubifs_end_scan(c, sleb, lnum, offs); + + if (need_clean) { + err = fix_unclean_leb(c, sleb, start); + if (err) + goto error; + } + + return sleb; + +corrupted: + ubifs_scanned_corruption(c, lnum, offs, buf); + err = -EUCLEAN; +error: + ubifs_err("LEB %d scanning failed", lnum); + ubifs_scan_destroy(sleb); + return ERR_PTR(err); +} + +/** + * get_cs_sqnum - get commit start sequence number. + * @c: UBIFS file-system description object + * @lnum: LEB number of commit start node + * @offs: offset of commit start node + * @cs_sqnum: commit start sequence number is returned here + * + * This function returns %0 on success and a negative error code on failure. + */ +static int get_cs_sqnum(struct ubifs_info *c, int lnum, int offs, + unsigned long long *cs_sqnum) +{ + struct ubifs_cs_node *cs_node = NULL; + int err, ret; + + dbg_rcvry("at %d:%d", lnum, offs); + cs_node = kmalloc(UBIFS_CS_NODE_SZ, GFP_KERNEL); + if (!cs_node) + return -ENOMEM; + if (c->leb_size - offs < UBIFS_CS_NODE_SZ) + goto out_err; + err = ubi_read(c->ubi, lnum, (void *)cs_node, offs, UBIFS_CS_NODE_SZ); + if (err && err != -EBADMSG) + goto out_free; + ret = ubifs_scan_a_node(c, cs_node, UBIFS_CS_NODE_SZ, lnum, offs, 0); + if (ret != SCANNED_A_NODE) { + dbg_err("Not a valid node"); + goto out_err; + } + if (cs_node->ch.node_type != UBIFS_CS_NODE) { + dbg_err("Node a CS node, type is %d", cs_node->ch.node_type); + goto out_err; + } + if (le64_to_cpu(cs_node->cmt_no) != c->cmt_no) { + dbg_err("CS node cmt_no %llu != current cmt_no %llu", + (unsigned long long)le64_to_cpu(cs_node->cmt_no), + c->cmt_no); + goto out_err; + } + *cs_sqnum = le64_to_cpu(cs_node->ch.sqnum); + dbg_rcvry("commit start sqnum %llu", *cs_sqnum); + kfree(cs_node); + return 0; + +out_err: + err = -EINVAL; +out_free: + ubifs_err("failed to get CS sqnum"); + kfree(cs_node); + return err; +} + +/** + * ubifs_recover_log_leb - scan and recover a log LEB. + * @c: UBIFS file-system description object + * @lnum: LEB number + * @offs: offset + * @sbuf: LEB-sized buffer to use + * + * This function does a scan of a LEB, but caters for errors that might have + * been caused by the unclean unmount from which we are attempting to recover. + * + * This function returns %0 on success and a negative error code on failure. + */ +struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum, + int offs, void *sbuf) +{ + struct ubifs_scan_leb *sleb; + int next_lnum; + + dbg_rcvry("LEB %d", lnum); + next_lnum = lnum + 1; + if (next_lnum >= UBIFS_LOG_LNUM + c->log_lebs) + next_lnum = UBIFS_LOG_LNUM; + if (next_lnum != c->ltail_lnum) { + /* + * We can only recover at the end of the log, so check that the + * next log LEB is empty or out of date. + */ + sleb = ubifs_scan(c, next_lnum, 0, sbuf); + if (IS_ERR(sleb)) + return sleb; + if (sleb->nodes_cnt) { + struct ubifs_scan_node *snod; + unsigned long long cs_sqnum = c->cs_sqnum; + + snod = list_entry(sleb->nodes.next, + struct ubifs_scan_node, list); + if (cs_sqnum == 0) { + int err; + + err = get_cs_sqnum(c, lnum, offs, &cs_sqnum); + if (err) { + ubifs_scan_destroy(sleb); + return ERR_PTR(err); + } + } + if (snod->sqnum > cs_sqnum) { + ubifs_err("unrecoverable log corruption " + "in LEB %d", lnum); + ubifs_scan_destroy(sleb); + return ERR_PTR(-EUCLEAN); + } + } + ubifs_scan_destroy(sleb); + } + return ubifs_recover_leb(c, lnum, offs, sbuf, 0); +} + +/** + * recover_head - recover a head. + * @c: UBIFS file-system description object + * @lnum: LEB number of head to recover + * @offs: offset of head to recover + * @sbuf: LEB-sized buffer to use + * + * This function ensures that there is no data on the flash at a head location. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int recover_head(const struct ubifs_info *c, int lnum, int offs, + void *sbuf) +{ + int len, err, need_clean = 0; + + if (c->min_io_size > 1) + len = c->min_io_size; + else + len = 512; + if (offs + len > c->leb_size) + len = c->leb_size - offs; + + if (!len) + return 0; + + /* Read at the head location and check it is empty flash */ + err = ubi_read(c->ubi, lnum, sbuf, offs, len); + if (err) + need_clean = 1; + else { + uint8_t *p = sbuf; + + while (len--) + if (*p++ != 0xff) { + need_clean = 1; + break; + } + } + + if (need_clean) { + dbg_rcvry("cleaning head at %d:%d", lnum, offs); + if (offs == 0) + return ubifs_leb_unmap(c, lnum); + err = ubi_read(c->ubi, lnum, sbuf, 0, offs); + if (err) + return err; + return ubi_leb_change(c->ubi, lnum, sbuf, offs, UBI_UNKNOWN); + } + + return 0; +} + +/** + * ubifs_recover_inl_heads - recover index and LPT heads. + * @c: UBIFS file-system description object + * @sbuf: LEB-sized buffer to use + * + * This function ensures that there is no data on the flash at the index and + * LPT head locations. + * + * This deals with the recovery of a half-completed journal commit. UBIFS is + * careful never to overwrite the last version of the index or the LPT. Because + * the index and LPT are wandering trees, data from a half-completed commit will + * not be referenced anywhere in UBIFS. The data will be either in LEBs that are + * assumed to be empty and will be unmapped anyway before use, or in the index + * and LPT heads. + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_recover_inl_heads(const struct ubifs_info *c, void *sbuf) +{ + int err; + + ubifs_assert(!(c->vfs_sb->s_flags & MS_RDONLY) || c->remounting_rw); + + dbg_rcvry("checking index head at %d:%d", c->ihead_lnum, c->ihead_offs); + err = recover_head(c, c->ihead_lnum, c->ihead_offs, sbuf); + if (err) + return err; + + dbg_rcvry("checking LPT head at %d:%d", c->nhead_lnum, c->nhead_offs); + err = recover_head(c, c->nhead_lnum, c->nhead_offs, sbuf); + if (err) + return err; + + return 0; +} + +/** + * clean_an_unclean_leb - read and write a LEB to remove corruption. + * @c: UBIFS file-system description object + * @ucleb: unclean LEB information + * @sbuf: LEB-sized buffer to use + * + * This function reads a LEB up to a point pre-determined by the mount recovery, + * checks the nodes, and writes the result back to the flash, thereby cleaning + * off any following corruption, or non-fatal ECC errors. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int clean_an_unclean_leb(const struct ubifs_info *c, + struct ubifs_unclean_leb *ucleb, void *sbuf) +{ + int err, lnum = ucleb->lnum, offs = 0, len = ucleb->endpt, quiet = 1; + void *buf = sbuf; + + dbg_rcvry("LEB %d len %d", lnum, len); + + if (len == 0) { + /* Nothing to read, just unmap it */ + err = ubifs_leb_unmap(c, lnum); + if (err) + return err; + return 0; + } + + err = ubi_read(c->ubi, lnum, buf, offs, len); + if (err && err != -EBADMSG) + return err; + + while (len >= 8) { + int ret; + + cond_resched(); + + /* Scan quietly until there is an error */ + ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet); + + if (ret == SCANNED_A_NODE) { + /* A valid node, and not a padding node */ + struct ubifs_ch *ch = buf; + int node_len; + + node_len = ALIGN(le32_to_cpu(ch->len), 8); + offs += node_len; + buf += node_len; + len -= node_len; + continue; + } + + if (ret > 0) { + /* Padding bytes or a valid padding node */ + offs += ret; + buf += ret; + len -= ret; + continue; + } + + if (ret == SCANNED_EMPTY_SPACE) { + ubifs_err("unexpected empty space at %d:%d", + lnum, offs); + return -EUCLEAN; + } + + if (quiet) { + /* Redo the last scan but noisily */ + quiet = 0; + continue; + } + + ubifs_scanned_corruption(c, lnum, offs, buf); + return -EUCLEAN; + } + + /* Pad to min_io_size */ + len = ALIGN(ucleb->endpt, c->min_io_size); + if (len > ucleb->endpt) { + int pad_len = len - ALIGN(ucleb->endpt, 8); + + if (pad_len > 0) { + buf = c->sbuf + len - pad_len; + ubifs_pad(c, buf, pad_len); + } + } + + /* Write back the LEB atomically */ + err = ubi_leb_change(c->ubi, lnum, sbuf, len, UBI_UNKNOWN); + if (err) + return err; + + dbg_rcvry("cleaned LEB %d", lnum); + + return 0; +} + +/** + * ubifs_clean_lebs - clean LEBs recovered during read-only mount. + * @c: UBIFS file-system description object + * @sbuf: LEB-sized buffer to use + * + * This function cleans a LEB identified during recovery that needs to be + * written but was not because UBIFS was mounted read-only. This happens when + * remounting to read-write mode. + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_clean_lebs(const struct ubifs_info *c, void *sbuf) +{ + dbg_rcvry("recovery"); + while (!list_empty(&c->unclean_leb_list)) { + struct ubifs_unclean_leb *ucleb; + int err; + + ucleb = list_entry(c->unclean_leb_list.next, + struct ubifs_unclean_leb, list); + err = clean_an_unclean_leb(c, ucleb, sbuf); + if (err) + return err; + list_del(&ucleb->list); + kfree(ucleb); + } + return 0; +} + +/** + * struct size_entry - inode size information for recovery. + * @rb: link in the RB-tree of sizes + * @inum: inode number + * @i_size: size on inode + * @d_size: maximum size based on data nodes + * @exists: indicates whether the inode exists + * @inode: inode if pinned in memory awaiting rw mode to fix it + */ +struct size_entry { + struct rb_node rb; + ino_t inum; + loff_t i_size; + loff_t d_size; + int exists; + struct inode *inode; +}; + +/** + * add_ino - add an entry to the size tree. + * @c: UBIFS file-system description object + * @inum: inode number + * @i_size: size on inode + * @d_size: maximum size based on data nodes + * @exists: indicates whether the inode exists + */ +static int add_ino(struct ubifs_info *c, ino_t inum, loff_t i_size, + loff_t d_size, int exists) +{ + struct rb_node **p = &c->size_tree.rb_node, *parent = NULL; + struct size_entry *e; + + while (*p) { + parent = *p; + e = rb_entry(parent, struct size_entry, rb); + if (inum < e->inum) + p = &(*p)->rb_left; + else + p = &(*p)->rb_right; + } + + e = kzalloc(sizeof(struct size_entry), GFP_KERNEL); + if (!e) + return -ENOMEM; + + e->inum = inum; + e->i_size = i_size; + e->d_size = d_size; + e->exists = exists; + + rb_link_node(&e->rb, parent, p); + rb_insert_color(&e->rb, &c->size_tree); + + return 0; +} + +/** + * find_ino - find an entry on the size tree. + * @c: UBIFS file-system description object + * @inum: inode number + */ +static struct size_entry *find_ino(struct ubifs_info *c, ino_t inum) +{ + struct rb_node *p = c->size_tree.rb_node; + struct size_entry *e; + + while (p) { + e = rb_entry(p, struct size_entry, rb); + if (inum < e->inum) + p = p->rb_left; + else if (inum > e->inum) + p = p->rb_right; + else + return e; + } + return NULL; +} + +/** + * remove_ino - remove an entry from the size tree. + * @c: UBIFS file-system description object + * @inum: inode number + */ +static void remove_ino(struct ubifs_info *c, ino_t inum) +{ + struct size_entry *e = find_ino(c, inum); + + if (!e) + return; + rb_erase(&e->rb, &c->size_tree); + kfree(e); +} + +/** + * ubifs_recover_size_accum - accumulate inode sizes for recovery. + * @c: UBIFS file-system description object + * @key: node key + * @deletion: node is for a deletion + * @new_size: inode size + * + * This function has two purposes: + * 1) to ensure there are no data nodes that fall outside the inode size + * 2) to ensure there are no data nodes for inodes that do not exist + * To accomplish those purposes, a rb-tree is constructed containing an entry + * for each inode number in the journal that has not been deleted, and recording + * the size from the inode node, the maximum size of any data node (also altered + * by truncations) and a flag indicating a inode number for which no inode node + * was present in the journal. + * + * Note that there is still the possibility that there are data nodes that have + * been committed that are beyond the inode size, however the only way to find + * them would be to scan the entire index. Alternatively, some provision could + * be made to record the size of inodes at the start of commit, which would seem + * very cumbersome for a scenario that is quite unlikely and the only negative + * consequence of which is wasted space. + * + * This functions returns %0 on success and a negative error code on failure. + */ +int ubifs_recover_size_accum(struct ubifs_info *c, union ubifs_key *key, + int deletion, loff_t new_size) +{ + ino_t inum = key_inum(c, key); + struct size_entry *e; + int err; + + switch (key_type(c, key)) { + case UBIFS_INO_KEY: + if (deletion) + remove_ino(c, inum); + else { + e = find_ino(c, inum); + if (e) { + e->i_size = new_size; + e->exists = 1; + } else { + err = add_ino(c, inum, new_size, 0, 1); + if (err) + return err; + } + } + break; + case UBIFS_DATA_KEY: + e = find_ino(c, inum); + if (e) { + if (new_size > e->d_size) + e->d_size = new_size; + } else { + err = add_ino(c, inum, 0, new_size, 0); + if (err) + return err; + } + break; + case UBIFS_TRUN_KEY: + e = find_ino(c, inum); + if (e) + e->d_size = new_size; + break; + } + return 0; +} + +/** + * ubifs_recover_size - recover inode size. + * @c: UBIFS file-system description object + * + * This function attempts to fix inode size discrepancies identified by the + * 'ubifs_recover_size_accum()' function. + * + * This functions returns %0 on success and a negative error code on failure. + */ +int ubifs_recover_size(struct ubifs_info *c) +{ + struct rb_node *this = rb_first(&c->size_tree); + + while (this) { + struct size_entry *e; + int err; + + e = rb_entry(this, struct size_entry, rb); + if (!e->exists) { + union ubifs_key key; + + ino_key_init(c, &key, e->inum); + err = ubifs_tnc_lookup(c, &key, c->sbuf); + if (err && err != -ENOENT) + return err; + if (err == -ENOENT) { + /* Remove data nodes that have no inode */ + dbg_rcvry("removing ino %lu", + (unsigned long)e->inum); + err = ubifs_tnc_remove_ino(c, e->inum); + if (err) + return err; + } else { + struct ubifs_ino_node *ino = c->sbuf; + + e->exists = 1; + e->i_size = le64_to_cpu(ino->size); + } + } + if (e->exists && e->i_size < e->d_size) { + if (!e->inode && (c->vfs_sb->s_flags & MS_RDONLY)) { + /* Fix the inode size and pin it in memory */ + struct inode *inode; + + inode = ubifs_iget(c->vfs_sb, e->inum); + if (IS_ERR(inode)) + return PTR_ERR(inode); + if (inode->i_size < e->d_size) { + dbg_rcvry("ino %lu size %lld -> %lld", + (unsigned long)e->inum, + e->d_size, inode->i_size); + inode->i_size = e->d_size; + ubifs_inode(inode)->ui_size = e->d_size; + e->inode = inode; + this = rb_next(this); + continue; + } + iput(inode); + } + } + this = rb_next(this); + rb_erase(&e->rb, &c->size_tree); + kfree(e); + } + return 0; +} diff --git a/fs/ubifs/replay.c b/fs/ubifs/replay.c new file mode 100644 index 0000000..da33a14 --- /dev/null +++ b/fs/ubifs/replay.c @@ -0,0 +1,1070 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file contains journal replay code. It runs when the file-system is being + * mounted and requires no locking. + * + * The larger is the journal, the longer it takes to scan it, so the longer it + * takes to mount UBIFS. This is why the journal has limited size which may be + * changed depending on the system requirements. But a larger journal gives + * faster I/O speed because it writes the index less frequently. So this is a + * trade-off. Also, the journal is indexed by the in-memory index (TNC), so the + * larger is the journal, the more memory its index may consume. + */ + +#include "ubifs.h" + +/* + * Replay flags. + * + * REPLAY_DELETION: node was deleted + * REPLAY_REF: node is a reference node + */ +enum { + REPLAY_DELETION = 1, + REPLAY_REF = 2, +}; + +/** + * struct replay_entry - replay tree entry. + * @lnum: logical eraseblock number of the node + * @offs: node offset + * @len: node length + * @sqnum: node sequence number + * @flags: replay flags + * @rb: links the replay tree + * @key: node key + * @nm: directory entry name + * @old_size: truncation old size + * @new_size: truncation new size + * @free: amount of free space in a bud + * @dirty: amount of dirty space in a bud from padding and deletion nodes + * + * UBIFS journal replay must compare node sequence numbers, which means it must + * build a tree of node information to insert into the TNC. + */ +struct replay_entry { + int lnum; + int offs; + int len; + unsigned long long sqnum; + int flags; + struct rb_node rb; + union ubifs_key key; + union { + struct qstr nm; + struct { + loff_t old_size; + loff_t new_size; + }; + struct { + int free; + int dirty; + }; + }; +}; + +/** + * struct bud_entry - entry in the list of buds to replay. + * @list: next bud in the list + * @bud: bud description object + * @free: free bytes in the bud + * @sqnum: reference node sequence number + */ +struct bud_entry { + struct list_head list; + struct ubifs_bud *bud; + int free; + unsigned long long sqnum; +}; + +/** + * set_bud_lprops - set free and dirty space used by a bud. + * @c: UBIFS file-system description object + * @r: replay entry of bud + */ +static int set_bud_lprops(struct ubifs_info *c, struct replay_entry *r) +{ + const struct ubifs_lprops *lp; + int err = 0, dirty; + + ubifs_get_lprops(c); + + lp = ubifs_lpt_lookup_dirty(c, r->lnum); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + goto out; + } + + dirty = lp->dirty; + if (r->offs == 0 && (lp->free != c->leb_size || lp->dirty != 0)) { + /* + * The LEB was added to the journal with a starting offset of + * zero which means the LEB must have been empty. The LEB + * property values should be lp->free == c->leb_size and + * lp->dirty == 0, but that is not the case. The reason is that + * the LEB was garbage collected. The garbage collector resets + * the free and dirty space without recording it anywhere except + * lprops, so if there is not a commit then lprops does not have + * that information next time the file system is mounted. + * + * We do not need to adjust free space because the scan has told + * us the exact value which is recorded in the replay entry as + * r->free. + * + * However we do need to subtract from the dirty space the + * amount of space that the garbage collector reclaimed, which + * is the whole LEB minus the amount of space that was free. + */ + dbg_mnt("bud LEB %d was GC'd (%d free, %d dirty)", r->lnum, + lp->free, lp->dirty); + dbg_gc("bud LEB %d was GC'd (%d free, %d dirty)", r->lnum, + lp->free, lp->dirty); + dirty -= c->leb_size - lp->free; + /* + * If the replay order was perfect the dirty space would now be + * zero. The order is not perfect because the the journal heads + * race with each other. This is not a problem but is does mean + * that the dirty space may temporarily exceed c->leb_size + * during the replay. + */ + if (dirty != 0) + dbg_msg("LEB %d lp: %d free %d dirty " + "replay: %d free %d dirty", r->lnum, lp->free, + lp->dirty, r->free, r->dirty); + } + lp = ubifs_change_lp(c, lp, r->free, dirty + r->dirty, + lp->flags | LPROPS_TAKEN, 0); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + goto out; + } +out: + ubifs_release_lprops(c); + return err; +} + +/** + * trun_remove_range - apply a replay entry for a truncation to the TNC. + * @c: UBIFS file-system description object + * @r: replay entry of truncation + */ +static int trun_remove_range(struct ubifs_info *c, struct replay_entry *r) +{ + unsigned min_blk, max_blk; + union ubifs_key min_key, max_key; + ino_t ino; + + min_blk = r->new_size / UBIFS_BLOCK_SIZE; + if (r->new_size & (UBIFS_BLOCK_SIZE - 1)) + min_blk += 1; + + max_blk = r->old_size / UBIFS_BLOCK_SIZE; + if ((r->old_size & (UBIFS_BLOCK_SIZE - 1)) == 0) + max_blk -= 1; + + ino = key_inum(c, &r->key); + + data_key_init(c, &min_key, ino, min_blk); + data_key_init(c, &max_key, ino, max_blk); + + return ubifs_tnc_remove_range(c, &min_key, &max_key); +} + +/** + * apply_replay_entry - apply a replay entry to the TNC. + * @c: UBIFS file-system description object + * @r: replay entry to apply + * + * Apply a replay entry to the TNC. + */ +static int apply_replay_entry(struct ubifs_info *c, struct replay_entry *r) +{ + int err, deletion = ((r->flags & REPLAY_DELETION) != 0); + + dbg_mnt("LEB %d:%d len %d flgs %d sqnum %llu %s", r->lnum, + r->offs, r->len, r->flags, r->sqnum, DBGKEY(&r->key)); + + /* Set c->replay_sqnum to help deal with dangling branches. */ + c->replay_sqnum = r->sqnum; + + if (r->flags & REPLAY_REF) + err = set_bud_lprops(c, r); + else if (is_hash_key(c, &r->key)) { + if (deletion) + err = ubifs_tnc_remove_nm(c, &r->key, &r->nm); + else + err = ubifs_tnc_add_nm(c, &r->key, r->lnum, r->offs, + r->len, &r->nm); + } else { + if (deletion) + switch (key_type(c, &r->key)) { + case UBIFS_INO_KEY: + { + ino_t inum = key_inum(c, &r->key); + + err = ubifs_tnc_remove_ino(c, inum); + break; + } + case UBIFS_TRUN_KEY: + err = trun_remove_range(c, r); + break; + default: + err = ubifs_tnc_remove(c, &r->key); + break; + } + else + err = ubifs_tnc_add(c, &r->key, r->lnum, r->offs, + r->len); + if (err) + return err; + + if (c->need_recovery) + err = ubifs_recover_size_accum(c, &r->key, deletion, + r->new_size); + } + + return err; +} + +/** + * destroy_replay_tree - destroy the replay. + * @c: UBIFS file-system description object + * + * Destroy the replay tree. + */ +static void destroy_replay_tree(struct ubifs_info *c) +{ + struct rb_node *this = c->replay_tree.rb_node; + struct replay_entry *r; + + while (this) { + if (this->rb_left) { + this = this->rb_left; + continue; + } else if (this->rb_right) { + this = this->rb_right; + continue; + } + r = rb_entry(this, struct replay_entry, rb); + this = rb_parent(this); + if (this) { + if (this->rb_left == &r->rb) + this->rb_left = NULL; + else + this->rb_right = NULL; + } + if (is_hash_key(c, &r->key)) + kfree((void *)r->nm.name); + kfree(r); + } + c->replay_tree = RB_ROOT; +} + +/** + * apply_replay_tree - apply the replay tree to the TNC. + * @c: UBIFS file-system description object + * + * Apply the replay tree. + * Returns zero in case of success and a negative error code in case of + * failure. + */ +static int apply_replay_tree(struct ubifs_info *c) +{ + struct rb_node *this = rb_first(&c->replay_tree); + + while (this) { + struct replay_entry *r; + int err; + + cond_resched(); + + r = rb_entry(this, struct replay_entry, rb); + err = apply_replay_entry(c, r); + if (err) + return err; + this = rb_next(this); + } + return 0; +} + +/** + * insert_node - insert a node to the replay tree. + * @c: UBIFS file-system description object + * @lnum: node logical eraseblock number + * @offs: node offset + * @len: node length + * @key: node key + * @sqnum: sequence number + * @deletion: non-zero if this is a deletion + * @used: number of bytes in use in a LEB + * @old_size: truncation old size + * @new_size: truncation new size + * + * This function inserts a scanned non-direntry node to the replay tree. The + * replay tree is an RB-tree containing @struct replay_entry elements which are + * indexed by the sequence number. The replay tree is applied at the very end + * of the replay process. Since the tree is sorted in sequence number order, + * the older modifications are applied first. This function returns zero in + * case of success and a negative error code in case of failure. + */ +static int insert_node(struct ubifs_info *c, int lnum, int offs, int len, + union ubifs_key *key, unsigned long long sqnum, + int deletion, int *used, loff_t old_size, + loff_t new_size) +{ + struct rb_node **p = &c->replay_tree.rb_node, *parent = NULL; + struct replay_entry *r; + + if (key_inum(c, key) >= c->highest_inum) + c->highest_inum = key_inum(c, key); + + dbg_mnt("add LEB %d:%d, key %s", lnum, offs, DBGKEY(key)); + while (*p) { + parent = *p; + r = rb_entry(parent, struct replay_entry, rb); + if (sqnum < r->sqnum) { + p = &(*p)->rb_left; + continue; + } else if (sqnum > r->sqnum) { + p = &(*p)->rb_right; + continue; + } + ubifs_err("duplicate sqnum in replay"); + return -EINVAL; + } + + r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL); + if (!r) + return -ENOMEM; + + if (!deletion) + *used += ALIGN(len, 8); + r->lnum = lnum; + r->offs = offs; + r->len = len; + r->sqnum = sqnum; + r->flags = (deletion ? REPLAY_DELETION : 0); + r->old_size = old_size; + r->new_size = new_size; + key_copy(c, key, &r->key); + + rb_link_node(&r->rb, parent, p); + rb_insert_color(&r->rb, &c->replay_tree); + return 0; +} + +/** + * insert_dent - insert a directory entry node into the replay tree. + * @c: UBIFS file-system description object + * @lnum: node logical eraseblock number + * @offs: node offset + * @len: node length + * @key: node key + * @name: directory entry name + * @nlen: directory entry name length + * @sqnum: sequence number + * @deletion: non-zero if this is a deletion + * @used: number of bytes in use in a LEB + * + * This function inserts a scanned directory entry node to the replay tree. + * Returns zero in case of success and a negative error code in case of + * failure. + * + * This function is also used for extended attribute entries because they are + * implemented as directory entry nodes. + */ +static int insert_dent(struct ubifs_info *c, int lnum, int offs, int len, + union ubifs_key *key, const char *name, int nlen, + unsigned long long sqnum, int deletion, int *used) +{ + struct rb_node **p = &c->replay_tree.rb_node, *parent = NULL; + struct replay_entry *r; + char *nbuf; + + if (key_inum(c, key) >= c->highest_inum) + c->highest_inum = key_inum(c, key); + + dbg_mnt("add LEB %d:%d, key %s", lnum, offs, DBGKEY(key)); + while (*p) { + parent = *p; + r = rb_entry(parent, struct replay_entry, rb); + if (sqnum < r->sqnum) { + p = &(*p)->rb_left; + continue; + } + if (sqnum > r->sqnum) { + p = &(*p)->rb_right; + continue; + } + ubifs_err("duplicate sqnum in replay"); + return -EINVAL; + } + + r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL); + if (!r) + return -ENOMEM; + nbuf = kmalloc(nlen + 1, GFP_KERNEL); + if (!nbuf) { + kfree(r); + return -ENOMEM; + } + + if (!deletion) + *used += ALIGN(len, 8); + r->lnum = lnum; + r->offs = offs; + r->len = len; + r->sqnum = sqnum; + r->nm.len = nlen; + memcpy(nbuf, name, nlen); + nbuf[nlen] = '\0'; + r->nm.name = nbuf; + r->flags = (deletion ? REPLAY_DELETION : 0); + key_copy(c, key, &r->key); + + ubifs_assert(!*p); + rb_link_node(&r->rb, parent, p); + rb_insert_color(&r->rb, &c->replay_tree); + return 0; +} + +/** + * ubifs_validate_entry - validate directory or extended attribute entry node. + * @c: UBIFS file-system description object + * @dent: the node to validate + * + * This function validates directory or extended attribute entry node @dent. + * Returns zero if the node is all right and a %-EINVAL if not. + */ +int ubifs_validate_entry(struct ubifs_info *c, + const struct ubifs_dent_node *dent) +{ + int key_type = key_type_flash(c, dent->key); + int nlen = le16_to_cpu(dent->nlen); + + if (le32_to_cpu(dent->ch.len) != nlen + UBIFS_DENT_NODE_SZ + 1 || + dent->type >= UBIFS_ITYPES_CNT || + nlen > UBIFS_MAX_NLEN || dent->name[nlen] != 0 || + strnlen((char *)dent->name, nlen) != nlen || + le64_to_cpu(dent->inum) > MAX_INUM) { + ubifs_err("bad %s node", key_type == UBIFS_DENT_KEY ? + "directory entry" : "extended attribute entry"); + return -EINVAL; + } + + if (key_type != UBIFS_DENT_KEY && key_type != UBIFS_XENT_KEY) { + ubifs_err("bad key type %d", key_type); + return -EINVAL; + } + + return 0; +} + +/** + * replay_bud - replay a bud logical eraseblock. + * @c: UBIFS file-system description object + * @lnum: bud logical eraseblock number to replay + * @offs: bud start offset + * @jhead: journal head to which this bud belongs + * @free: amount of free space in the bud is returned here + * @dirty: amount of dirty space from padding and deletion nodes is returned + * here + * + * This function returns zero in case of success and a negative error code in + * case of failure. + */ +static int replay_bud(struct ubifs_info *c, int lnum, int offs, int jhead, + int *free, int *dirty) +{ + int err = 0, used = 0; + struct ubifs_scan_leb *sleb; + struct ubifs_scan_node *snod; + struct ubifs_bud *bud; + + dbg_mnt("replay bud LEB %d, head %d", lnum, jhead); + if (c->need_recovery) + sleb = ubifs_recover_leb(c, lnum, offs, c->sbuf, jhead != GCHD); + else + sleb = ubifs_scan(c, lnum, offs, c->sbuf); + if (IS_ERR(sleb)) + return PTR_ERR(sleb); + + /* + * The bud does not have to start from offset zero - the beginning of + * the 'lnum' LEB may contain previously committed data. One of the + * things we have to do in replay is to correctly update lprops with + * newer information about this LEB. + * + * At this point lprops thinks that this LEB has 'c->leb_size - offs' + * bytes of free space because it only contain information about + * committed data. + * + * But we know that real amount of free space is 'c->leb_size - + * sleb->endpt', and the space in the 'lnum' LEB between 'offs' and + * 'sleb->endpt' is used by bud data. We have to correctly calculate + * how much of these data are dirty and update lprops with this + * information. + * + * The dirt in that LEB region is comprised of padding nodes, deletion + * nodes, truncation nodes and nodes which are obsoleted by subsequent + * nodes in this LEB. So instead of calculating clean space, we + * calculate used space ('used' variable). + */ + + list_for_each_entry(snod, &sleb->nodes, list) { + int deletion = 0; + + cond_resched(); + + if (snod->sqnum >= SQNUM_WATERMARK) { + ubifs_err("file system's life ended"); + goto out_dump; + } + + if (snod->sqnum > c->max_sqnum) + c->max_sqnum = snod->sqnum; + + switch (snod->type) { + case UBIFS_INO_NODE: + { + struct ubifs_ino_node *ino = snod->node; + loff_t new_size = le64_to_cpu(ino->size); + + if (le32_to_cpu(ino->nlink) == 0) + deletion = 1; + err = insert_node(c, lnum, snod->offs, snod->len, + &snod->key, snod->sqnum, deletion, + &used, 0, new_size); + break; + } + case UBIFS_DATA_NODE: + { + struct ubifs_data_node *dn = snod->node; + loff_t new_size = le32_to_cpu(dn->size) + + key_block(c, &snod->key) * + UBIFS_BLOCK_SIZE; + + err = insert_node(c, lnum, snod->offs, snod->len, + &snod->key, snod->sqnum, deletion, + &used, 0, new_size); + break; + } + case UBIFS_DENT_NODE: + case UBIFS_XENT_NODE: + { + struct ubifs_dent_node *dent = snod->node; + + err = ubifs_validate_entry(c, dent); + if (err) + goto out_dump; + + err = insert_dent(c, lnum, snod->offs, snod->len, + &snod->key, (char *)dent->name, + le16_to_cpu(dent->nlen), snod->sqnum, + !le64_to_cpu(dent->inum), &used); + break; + } + case UBIFS_TRUN_NODE: + { + struct ubifs_trun_node *trun = snod->node; + loff_t old_size = le64_to_cpu(trun->old_size); + loff_t new_size = le64_to_cpu(trun->new_size); + union ubifs_key key; + + /* Validate truncation node */ + if (old_size < 0 || old_size > c->max_inode_sz || + new_size < 0 || new_size > c->max_inode_sz || + old_size <= new_size) { + ubifs_err("bad truncation node"); + goto out_dump; + } + + /* + * Create a fake truncation key just to use the same + * functions which expect nodes to have keys. + */ + trun_key_init(c, &key, le32_to_cpu(trun->inum)); + err = insert_node(c, lnum, snod->offs, snod->len, + &key, snod->sqnum, 1, &used, + old_size, new_size); + break; + } + default: + ubifs_err("unexpected node type %d in bud LEB %d:%d", + snod->type, lnum, snod->offs); + err = -EINVAL; + goto out_dump; + } + if (err) + goto out; + } + + bud = ubifs_search_bud(c, lnum); + if (!bud) + BUG(); + + ubifs_assert(sleb->endpt - offs >= used); + ubifs_assert(sleb->endpt % c->min_io_size == 0); + + *dirty = sleb->endpt - offs - used; + *free = c->leb_size - sleb->endpt; + +out: + ubifs_scan_destroy(sleb); + return err; + +out_dump: + ubifs_err("bad node is at LEB %d:%d", lnum, snod->offs); + dbg_dump_node(c, snod->node); + ubifs_scan_destroy(sleb); + return -EINVAL; +} + +/** + * insert_ref_node - insert a reference node to the replay tree. + * @c: UBIFS file-system description object + * @lnum: node logical eraseblock number + * @offs: node offset + * @sqnum: sequence number + * @free: amount of free space in bud + * @dirty: amount of dirty space from padding and deletion nodes + * + * This function inserts a reference node to the replay tree and returns zero + * in case of success or a negative error code in case of failure. + */ +static int insert_ref_node(struct ubifs_info *c, int lnum, int offs, + unsigned long long sqnum, int free, int dirty) +{ + struct rb_node **p = &c->replay_tree.rb_node, *parent = NULL; + struct replay_entry *r; + + dbg_mnt("add ref LEB %d:%d", lnum, offs); + while (*p) { + parent = *p; + r = rb_entry(parent, struct replay_entry, rb); + if (sqnum < r->sqnum) { + p = &(*p)->rb_left; + continue; + } else if (sqnum > r->sqnum) { + p = &(*p)->rb_right; + continue; + } + ubifs_err("duplicate sqnum in replay tree"); + return -EINVAL; + } + + r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL); + if (!r) + return -ENOMEM; + + r->lnum = lnum; + r->offs = offs; + r->sqnum = sqnum; + r->flags = REPLAY_REF; + r->free = free; + r->dirty = dirty; + + rb_link_node(&r->rb, parent, p); + rb_insert_color(&r->rb, &c->replay_tree); + return 0; +} + +/** + * replay_buds - replay all buds. + * @c: UBIFS file-system description object + * + * This function returns zero in case of success and a negative error code in + * case of failure. + */ +static int replay_buds(struct ubifs_info *c) +{ + struct bud_entry *b; + int err, uninitialized_var(free), uninitialized_var(dirty); + + list_for_each_entry(b, &c->replay_buds, list) { + err = replay_bud(c, b->bud->lnum, b->bud->start, b->bud->jhead, + &free, &dirty); + if (err) + return err; + err = insert_ref_node(c, b->bud->lnum, b->bud->start, b->sqnum, + free, dirty); + if (err) + return err; + } + + return 0; +} + +/** + * destroy_bud_list - destroy the list of buds to replay. + * @c: UBIFS file-system description object + */ +static void destroy_bud_list(struct ubifs_info *c) +{ + struct bud_entry *b; + + while (!list_empty(&c->replay_buds)) { + b = list_entry(c->replay_buds.next, struct bud_entry, list); + list_del(&b->list); + kfree(b); + } +} + +/** + * add_replay_bud - add a bud to the list of buds to replay. + * @c: UBIFS file-system description object + * @lnum: bud logical eraseblock number to replay + * @offs: bud start offset + * @jhead: journal head to which this bud belongs + * @sqnum: reference node sequence number + * + * This function returns zero in case of success and a negative error code in + * case of failure. + */ +static int add_replay_bud(struct ubifs_info *c, int lnum, int offs, int jhead, + unsigned long long sqnum) +{ + struct ubifs_bud *bud; + struct bud_entry *b; + + dbg_mnt("add replay bud LEB %d:%d, head %d", lnum, offs, jhead); + + bud = kmalloc(sizeof(struct ubifs_bud), GFP_KERNEL); + if (!bud) + return -ENOMEM; + + b = kmalloc(sizeof(struct bud_entry), GFP_KERNEL); + if (!b) { + kfree(bud); + return -ENOMEM; + } + + bud->lnum = lnum; + bud->start = offs; + bud->jhead = jhead; + ubifs_add_bud(c, bud); + + b->bud = bud; + b->sqnum = sqnum; + list_add_tail(&b->list, &c->replay_buds); + + return 0; +} + +/** + * validate_ref - validate a reference node. + * @c: UBIFS file-system description object + * @ref: the reference node to validate + * @ref_lnum: LEB number of the reference node + * @ref_offs: reference node offset + * + * This function returns %1 if a bud reference already exists for the LEB. %0 is + * returned if the reference node is new, otherwise %-EINVAL is returned if + * validation failed. + */ +static int validate_ref(struct ubifs_info *c, const struct ubifs_ref_node *ref) +{ + struct ubifs_bud *bud; + int lnum = le32_to_cpu(ref->lnum); + unsigned int offs = le32_to_cpu(ref->offs); + unsigned int jhead = le32_to_cpu(ref->jhead); + + /* + * ref->offs may point to the end of LEB when the journal head points + * to the end of LEB and we write reference node for it during commit. + * So this is why we require 'offs > c->leb_size'. + */ + if (jhead >= c->jhead_cnt || lnum >= c->leb_cnt || + lnum < c->main_first || offs > c->leb_size || + offs & (c->min_io_size - 1)) + return -EINVAL; + + /* Make sure we have not already looked at this bud */ + bud = ubifs_search_bud(c, lnum); + if (bud) { + if (bud->jhead == jhead && bud->start <= offs) + return 1; + ubifs_err("bud at LEB %d:%d was already referred", lnum, offs); + return -EINVAL; + } + + return 0; +} + +/** + * replay_log_leb - replay a log logical eraseblock. + * @c: UBIFS file-system description object + * @lnum: log logical eraseblock to replay + * @offs: offset to start replaying from + * @sbuf: scan buffer + * + * This function replays a log LEB and returns zero in case of success, %1 if + * this is the last LEB in the log, and a negative error code in case of + * failure. + */ +static int replay_log_leb(struct ubifs_info *c, int lnum, int offs, void *sbuf) +{ + int err; + struct ubifs_scan_leb *sleb; + struct ubifs_scan_node *snod; + const struct ubifs_cs_node *node; + + dbg_mnt("replay log LEB %d:%d", lnum, offs); + sleb = ubifs_scan(c, lnum, offs, sbuf); + if (IS_ERR(sleb)) { + if (c->need_recovery) + sleb = ubifs_recover_log_leb(c, lnum, offs, sbuf); + if (IS_ERR(sleb)) + return PTR_ERR(sleb); + } + + if (sleb->nodes_cnt == 0) { + err = 1; + goto out; + } + + node = sleb->buf; + + snod = list_entry(sleb->nodes.next, struct ubifs_scan_node, list); + if (c->cs_sqnum == 0) { + /* + * This is the first log LEB we are looking at, make sure that + * the first node is a commit start node. Also record its + * sequence number so that UBIFS can determine where the log + * ends, because all nodes which were have higher sequence + * numbers. + */ + if (snod->type != UBIFS_CS_NODE) { + dbg_err("first log node at LEB %d:%d is not CS node", + lnum, offs); + goto out_dump; + } + if (le64_to_cpu(node->cmt_no) != c->cmt_no) { + dbg_err("first CS node at LEB %d:%d has wrong " + "commit number %llu expected %llu", + lnum, offs, + (unsigned long long)le64_to_cpu(node->cmt_no), + c->cmt_no); + goto out_dump; + } + + c->cs_sqnum = le64_to_cpu(node->ch.sqnum); + dbg_mnt("commit start sqnum %llu", c->cs_sqnum); + } + + if (snod->sqnum < c->cs_sqnum) { + /* + * This means that we reached end of log and now + * look to the older log data, which was already + * committed but the eraseblock was not erased (UBIFS + * only un-maps it). So this basically means we have to + * exit with "end of log" code. + */ + err = 1; + goto out; + } + + /* Make sure the first node sits at offset zero of the LEB */ + if (snod->offs != 0) { + dbg_err("first node is not at zero offset"); + goto out_dump; + } + + list_for_each_entry(snod, &sleb->nodes, list) { + + cond_resched(); + + if (snod->sqnum >= SQNUM_WATERMARK) { + ubifs_err("file system's life ended"); + goto out_dump; + } + + if (snod->sqnum < c->cs_sqnum) { + dbg_err("bad sqnum %llu, commit sqnum %llu", + snod->sqnum, c->cs_sqnum); + goto out_dump; + } + + if (snod->sqnum > c->max_sqnum) + c->max_sqnum = snod->sqnum; + + switch (snod->type) { + case UBIFS_REF_NODE: { + const struct ubifs_ref_node *ref = snod->node; + + err = validate_ref(c, ref); + if (err == 1) + break; /* Already have this bud */ + if (err) + goto out_dump; + + err = add_replay_bud(c, le32_to_cpu(ref->lnum), + le32_to_cpu(ref->offs), + le32_to_cpu(ref->jhead), + snod->sqnum); + if (err) + goto out; + + break; + } + case UBIFS_CS_NODE: + /* Make sure it sits at the beginning of LEB */ + if (snod->offs != 0) { + ubifs_err("unexpected node in log"); + goto out_dump; + } + break; + default: + ubifs_err("unexpected node in log"); + goto out_dump; + } + } + + if (sleb->endpt || c->lhead_offs >= c->leb_size) { + c->lhead_lnum = lnum; + c->lhead_offs = sleb->endpt; + } + + err = !sleb->endpt; +out: + ubifs_scan_destroy(sleb); + return err; + +out_dump: + ubifs_err("log error detected while replying the log at LEB %d:%d", + lnum, offs + snod->offs); + dbg_dump_node(c, snod->node); + ubifs_scan_destroy(sleb); + return -EINVAL; +} + +/** + * take_ihead - update the status of the index head in lprops to 'taken'. + * @c: UBIFS file-system description object + * + * This function returns the amount of free space in the index head LEB or a + * negative error code. + */ +static int take_ihead(struct ubifs_info *c) +{ + const struct ubifs_lprops *lp; + int err, free; + + ubifs_get_lprops(c); + + lp = ubifs_lpt_lookup_dirty(c, c->ihead_lnum); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + goto out; + } + + free = lp->free; + + lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC, + lp->flags | LPROPS_TAKEN, 0); + if (IS_ERR(lp)) { + err = PTR_ERR(lp); + goto out; + } + + err = free; +out: + ubifs_release_lprops(c); + return err; +} + +/** + * ubifs_replay_journal - replay journal. + * @c: UBIFS file-system description object + * + * This function scans the journal, replays and cleans it up. It makes sure all + * memory data structures related to uncommitted journal are built (dirty TNC + * tree, tree of buds, modified lprops, etc). + */ +int ubifs_replay_journal(struct ubifs_info *c) +{ + int err, i, lnum, offs, _free; + void *sbuf = NULL; + + BUILD_BUG_ON(UBIFS_TRUN_KEY > 5); + + /* Update the status of the index head in lprops to 'taken' */ + _free = take_ihead(c); + if (_free < 0) + return _free; /* Error code */ + + if (c->ihead_offs != c->leb_size - _free) { + ubifs_err("bad index head LEB %d:%d", c->ihead_lnum, + c->ihead_offs); + return -EINVAL; + } + + sbuf = vmalloc(c->leb_size); + if (!sbuf) + return -ENOMEM; + + dbg_mnt("start replaying the journal"); + + c->replaying = 1; + + lnum = c->ltail_lnum = c->lhead_lnum; + offs = c->lhead_offs; + + for (i = 0; i < c->log_lebs; i++, lnum++) { + if (lnum >= UBIFS_LOG_LNUM + c->log_lebs) { + /* + * The log is logically circular, we reached the last + * LEB, switch to the first one. + */ + lnum = UBIFS_LOG_LNUM; + offs = 0; + } + err = replay_log_leb(c, lnum, offs, sbuf); + if (err == 1) + /* We hit the end of the log */ + break; + if (err) + goto out; + offs = 0; + } + + err = replay_buds(c); + if (err) + goto out; + + err = apply_replay_tree(c); + if (err) + goto out; + + ubifs_assert(c->bud_bytes <= c->max_bud_bytes || c->need_recovery); + dbg_mnt("finished, log head LEB %d:%d, max_sqnum %llu, " + "highest_inum %lu", c->lhead_lnum, c->lhead_offs, c->max_sqnum, + (unsigned long)c->highest_inum); +out: + destroy_replay_tree(c); + destroy_bud_list(c); + vfree(sbuf); + c->replaying = 0; + return err; +} diff --git a/fs/ubifs/sb.c b/fs/ubifs/sb.c new file mode 100644 index 0000000..9708fda --- /dev/null +++ b/fs/ubifs/sb.c @@ -0,0 +1,324 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file implements UBIFS superblock. The superblock is stored at the first + * LEB of the volume and is never changed by UBIFS. Only user-space tools may + * change it. The superblock node mostly contains geometry information. + */ + +#include "ubifs.h" + +/* + * Default journal size in logical eraseblocks as a percent of total + * flash size. + */ +#define DEFAULT_JNL_PERCENT 5 + +/* Default maximum journal size in bytes */ +#define DEFAULT_MAX_JNL (32*1024*1024) + +/* Default indexing tree fanout */ +#define DEFAULT_FANOUT 8 + +/* Default number of data journal heads */ +#define DEFAULT_JHEADS_CNT 1 + +/* Default positions of different LEBs in the main area */ +#define DEFAULT_IDX_LEB 0 +#define DEFAULT_DATA_LEB 1 +#define DEFAULT_GC_LEB 2 + +/* Default number of LEB numbers in LPT's save table */ +#define DEFAULT_LSAVE_CNT 256 + +/* Default reserved pool size as a percent of maximum free space */ +#define DEFAULT_RP_PERCENT 5 + +/* The default maximum size of reserved pool in bytes */ +#define DEFAULT_MAX_RP_SIZE (5*1024*1024) + +/* Default time granularity in nanoseconds */ +#define DEFAULT_TIME_GRAN 1000000000 + +/** + * validate_sb - validate superblock node. + * @c: UBIFS file-system description object + * @sup: superblock node + * + * This function validates superblock node @sup. Since most of data was read + * from the superblock and stored in @c, the function validates fields in @c + * instead. Returns zero in case of success and %-EINVAL in case of validation + * failure. + */ +static int validate_sb(struct ubifs_info *c, struct ubifs_sb_node *sup) +{ + long long max_bytes; + int err = 1, min_leb_cnt; + + if (!c->key_hash) { + err = 2; + goto failed; + } + + if (sup->key_fmt != UBIFS_SIMPLE_KEY_FMT) { + err = 3; + goto failed; + } + + if (le32_to_cpu(sup->min_io_size) != c->min_io_size) { + ubifs_err("min. I/O unit mismatch: %d in superblock, %d real", + le32_to_cpu(sup->min_io_size), c->min_io_size); + goto failed; + } + + if (le32_to_cpu(sup->leb_size) != c->leb_size) { + ubifs_err("LEB size mismatch: %d in superblock, %d real", + le32_to_cpu(sup->leb_size), c->leb_size); + goto failed; + } + + if (c->log_lebs < UBIFS_MIN_LOG_LEBS || + c->lpt_lebs < UBIFS_MIN_LPT_LEBS || + c->orph_lebs < UBIFS_MIN_ORPH_LEBS || + c->main_lebs < UBIFS_MIN_MAIN_LEBS) { + err = 4; + goto failed; + } + + /* + * Calculate minimum allowed amount of main area LEBs. This is very + * similar to %UBIFS_MIN_LEB_CNT, but we take into account real what we + * have just read from the superblock. + */ + min_leb_cnt = UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs; + min_leb_cnt += c->lpt_lebs + c->orph_lebs + c->jhead_cnt + 6; + + if (c->leb_cnt < min_leb_cnt || c->leb_cnt > c->vi.size) { + ubifs_err("bad LEB count: %d in superblock, %d on UBI volume, " + "%d minimum required", c->leb_cnt, c->vi.size, + min_leb_cnt); + goto failed; + } + + if (c->max_leb_cnt < c->leb_cnt) { + ubifs_err("max. LEB count %d less than LEB count %d", + c->max_leb_cnt, c->leb_cnt); + goto failed; + } + + if (c->main_lebs < UBIFS_MIN_MAIN_LEBS) { + err = 7; + goto failed; + } + + if (c->max_bud_bytes < (long long)c->leb_size * UBIFS_MIN_BUD_LEBS || + c->max_bud_bytes > (long long)c->leb_size * c->main_lebs) { + err = 8; + goto failed; + } + + if (c->jhead_cnt < NONDATA_JHEADS_CNT + 1 || + c->jhead_cnt > NONDATA_JHEADS_CNT + UBIFS_MAX_JHEADS) { + err = 9; + goto failed; + } + + if (c->fanout < UBIFS_MIN_FANOUT || + ubifs_idx_node_sz(c, c->fanout) > c->leb_size) { + err = 10; + goto failed; + } + + if (c->lsave_cnt < 0 || (c->lsave_cnt > DEFAULT_LSAVE_CNT && + c->lsave_cnt > c->max_leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - + c->log_lebs - c->lpt_lebs - c->orph_lebs)) { + err = 11; + goto failed; + } + + if (UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs + c->lpt_lebs + + c->orph_lebs + c->main_lebs != c->leb_cnt) { + err = 12; + goto failed; + } + + if (c->default_compr < 0 || c->default_compr >= UBIFS_COMPR_TYPES_CNT) { + err = 13; + goto failed; + } + + max_bytes = c->main_lebs * (long long)c->leb_size; + if (c->rp_size < 0 || max_bytes < c->rp_size) { + err = 14; + goto failed; + } + + if (le32_to_cpu(sup->time_gran) > 1000000000 || + le32_to_cpu(sup->time_gran) < 1) { + err = 15; + goto failed; + } + + return 0; + +failed: + ubifs_err("bad superblock, error %d", err); + dbg_dump_node(c, sup); + return -EINVAL; +} + +/** + * ubifs_read_sb_node - read superblock node. + * @c: UBIFS file-system description object + * + * This function returns a pointer to the superblock node or a negative error + * code. + */ +struct ubifs_sb_node *ubifs_read_sb_node(struct ubifs_info *c) +{ + struct ubifs_sb_node *sup; + int err; + + sup = kmalloc(ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size), GFP_NOFS); + if (!sup) + return ERR_PTR(-ENOMEM); + + err = ubifs_read_node(c, sup, UBIFS_SB_NODE, UBIFS_SB_NODE_SZ, + UBIFS_SB_LNUM, 0); + if (err) { + kfree(sup); + return ERR_PTR(err); + } + + return sup; +} + +/** + * ubifs_read_superblock - read superblock. + * @c: UBIFS file-system description object + * + * This function finds, reads and checks the superblock. If an empty UBI volume + * is being mounted, this function creates default superblock. Returns zero in + * case of success, and a negative error code in case of failure. + */ +int ubifs_read_superblock(struct ubifs_info *c) +{ + int err, sup_flags; + struct ubifs_sb_node *sup; + + if (c->empty) { + printf("No UBIFS filesystem found!\n"); + return -1; + } + + sup = ubifs_read_sb_node(c); + if (IS_ERR(sup)) + return PTR_ERR(sup); + + /* + * The software supports all previous versions but not future versions, + * due to the unavailability of time-travelling equipment. + */ + c->fmt_version = le32_to_cpu(sup->fmt_version); + if (c->fmt_version > UBIFS_FORMAT_VERSION) { + ubifs_err("on-flash format version is %d, but software only " + "supports up to version %d", c->fmt_version, + UBIFS_FORMAT_VERSION); + err = -EINVAL; + goto out; + } + + if (c->fmt_version < 3) { + ubifs_err("on-flash format version %d is not supported", + c->fmt_version); + err = -EINVAL; + goto out; + } + + switch (sup->key_hash) { + case UBIFS_KEY_HASH_R5: + c->key_hash = key_r5_hash; + c->key_hash_type = UBIFS_KEY_HASH_R5; + break; + + case UBIFS_KEY_HASH_TEST: + c->key_hash = key_test_hash; + c->key_hash_type = UBIFS_KEY_HASH_TEST; + break; + }; + + c->key_fmt = sup->key_fmt; + + switch (c->key_fmt) { + case UBIFS_SIMPLE_KEY_FMT: + c->key_len = UBIFS_SK_LEN; + break; + default: + ubifs_err("unsupported key format"); + err = -EINVAL; + goto out; + } + + c->leb_cnt = le32_to_cpu(sup->leb_cnt); + c->max_leb_cnt = le32_to_cpu(sup->max_leb_cnt); + c->max_bud_bytes = le64_to_cpu(sup->max_bud_bytes); + c->log_lebs = le32_to_cpu(sup->log_lebs); + c->lpt_lebs = le32_to_cpu(sup->lpt_lebs); + c->orph_lebs = le32_to_cpu(sup->orph_lebs); + c->jhead_cnt = le32_to_cpu(sup->jhead_cnt) + NONDATA_JHEADS_CNT; + c->fanout = le32_to_cpu(sup->fanout); + c->lsave_cnt = le32_to_cpu(sup->lsave_cnt); + c->default_compr = le16_to_cpu(sup->default_compr); + c->rp_size = le64_to_cpu(sup->rp_size); + c->rp_uid = le32_to_cpu(sup->rp_uid); + c->rp_gid = le32_to_cpu(sup->rp_gid); + sup_flags = le32_to_cpu(sup->flags); + + c->vfs_sb->s_time_gran = le32_to_cpu(sup->time_gran); + memcpy(&c->uuid, &sup->uuid, 16); + c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT); + + /* Automatically increase file system size to the maximum size */ + c->old_leb_cnt = c->leb_cnt; + if (c->leb_cnt < c->vi.size && c->leb_cnt < c->max_leb_cnt) { + c->leb_cnt = min_t(int, c->max_leb_cnt, c->vi.size); + dbg_mnt("Auto resizing (ro) from %d LEBs to %d LEBs", + c->old_leb_cnt, c->leb_cnt); + } + + c->log_bytes = (long long)c->log_lebs * c->leb_size; + c->log_last = UBIFS_LOG_LNUM + c->log_lebs - 1; + c->lpt_first = UBIFS_LOG_LNUM + c->log_lebs; + c->lpt_last = c->lpt_first + c->lpt_lebs - 1; + c->orph_first = c->lpt_last + 1; + c->orph_last = c->orph_first + c->orph_lebs - 1; + c->main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS; + c->main_lebs -= c->log_lebs + c->lpt_lebs + c->orph_lebs; + c->main_first = c->leb_cnt - c->main_lebs; + c->report_rp_size = ubifs_reported_space(c, c->rp_size); + + err = validate_sb(c, sup); +out: + kfree(sup); + return err; +} diff --git a/fs/ubifs/scan.c b/fs/ubifs/scan.c new file mode 100644 index 0000000..0ed8247 --- /dev/null +++ b/fs/ubifs/scan.c @@ -0,0 +1,362 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements the scan which is a general-purpose function for + * determining what nodes are in an eraseblock. The scan is used to replay the + * journal, to do garbage collection. for the TNC in-the-gaps method, and by + * debugging functions. + */ + +#include "ubifs.h" + +/** + * scan_padding_bytes - scan for padding bytes. + * @buf: buffer to scan + * @len: length of buffer + * + * This function returns the number of padding bytes on success and + * %SCANNED_GARBAGE on failure. + */ +static int scan_padding_bytes(void *buf, int len) +{ + int pad_len = 0, max_pad_len = min_t(int, UBIFS_PAD_NODE_SZ, len); + uint8_t *p = buf; + + dbg_scan("not a node"); + + while (pad_len < max_pad_len && *p++ == UBIFS_PADDING_BYTE) + pad_len += 1; + + if (!pad_len || (pad_len & 7)) + return SCANNED_GARBAGE; + + dbg_scan("%d padding bytes", pad_len); + + return pad_len; +} + +/** + * ubifs_scan_a_node - scan for a node or padding. + * @c: UBIFS file-system description object + * @buf: buffer to scan + * @len: length of buffer + * @lnum: logical eraseblock number + * @offs: offset within the logical eraseblock + * @quiet: print no messages + * + * This function returns a scanning code to indicate what was scanned. + */ +int ubifs_scan_a_node(const struct ubifs_info *c, void *buf, int len, int lnum, + int offs, int quiet) +{ + struct ubifs_ch *ch = buf; + uint32_t magic; + + magic = le32_to_cpu(ch->magic); + + if (magic == 0xFFFFFFFF) { + dbg_scan("hit empty space"); + return SCANNED_EMPTY_SPACE; + } + + if (magic != UBIFS_NODE_MAGIC) + return scan_padding_bytes(buf, len); + + if (len < UBIFS_CH_SZ) + return SCANNED_GARBAGE; + + dbg_scan("scanning %s", dbg_ntype(ch->node_type)); + + if (ubifs_check_node(c, buf, lnum, offs, quiet, 1)) + return SCANNED_A_CORRUPT_NODE; + + if (ch->node_type == UBIFS_PAD_NODE) { + struct ubifs_pad_node *pad = buf; + int pad_len = le32_to_cpu(pad->pad_len); + int node_len = le32_to_cpu(ch->len); + + /* Validate the padding node */ + if (pad_len < 0 || + offs + node_len + pad_len > c->leb_size) { + if (!quiet) { + ubifs_err("bad pad node at LEB %d:%d", + lnum, offs); + dbg_dump_node(c, pad); + } + return SCANNED_A_BAD_PAD_NODE; + } + + /* Make the node pads to 8-byte boundary */ + if ((node_len + pad_len) & 7) { + if (!quiet) { + dbg_err("bad padding length %d - %d", + offs, offs + node_len + pad_len); + } + return SCANNED_A_BAD_PAD_NODE; + } + + dbg_scan("%d bytes padded, offset now %d", + pad_len, ALIGN(offs + node_len + pad_len, 8)); + + return node_len + pad_len; + } + + return SCANNED_A_NODE; +} + +/** + * ubifs_start_scan - create LEB scanning information at start of scan. + * @c: UBIFS file-system description object + * @lnum: logical eraseblock number + * @offs: offset to start at (usually zero) + * @sbuf: scan buffer (must be c->leb_size) + * + * This function returns %0 on success and a negative error code on failure. + */ +struct ubifs_scan_leb *ubifs_start_scan(const struct ubifs_info *c, int lnum, + int offs, void *sbuf) +{ + struct ubifs_scan_leb *sleb; + int err; + + dbg_scan("scan LEB %d:%d", lnum, offs); + + sleb = kzalloc(sizeof(struct ubifs_scan_leb), GFP_NOFS); + if (!sleb) + return ERR_PTR(-ENOMEM); + + sleb->lnum = lnum; + INIT_LIST_HEAD(&sleb->nodes); + sleb->buf = sbuf; + + err = ubi_read(c->ubi, lnum, sbuf + offs, offs, c->leb_size - offs); + if (err && err != -EBADMSG) { + ubifs_err("cannot read %d bytes from LEB %d:%d," + " error %d", c->leb_size - offs, lnum, offs, err); + kfree(sleb); + return ERR_PTR(err); + } + + if (err == -EBADMSG) + sleb->ecc = 1; + + return sleb; +} + +/** + * ubifs_end_scan - update LEB scanning information at end of scan. + * @c: UBIFS file-system description object + * @sleb: scanning information + * @lnum: logical eraseblock number + * @offs: offset to start at (usually zero) + * + * This function returns %0 on success and a negative error code on failure. + */ +void ubifs_end_scan(const struct ubifs_info *c, struct ubifs_scan_leb *sleb, + int lnum, int offs) +{ + lnum = lnum; + dbg_scan("stop scanning LEB %d at offset %d", lnum, offs); + ubifs_assert(offs % c->min_io_size == 0); + + sleb->endpt = ALIGN(offs, c->min_io_size); +} + +/** + * ubifs_add_snod - add a scanned node to LEB scanning information. + * @c: UBIFS file-system description object + * @sleb: scanning information + * @buf: buffer containing node + * @offs: offset of node on flash + * + * This function returns %0 on success and a negative error code on failure. + */ +int ubifs_add_snod(const struct ubifs_info *c, struct ubifs_scan_leb *sleb, + void *buf, int offs) +{ + struct ubifs_ch *ch = buf; + struct ubifs_ino_node *ino = buf; + struct ubifs_scan_node *snod; + + snod = kzalloc(sizeof(struct ubifs_scan_node), GFP_NOFS); + if (!snod) + return -ENOMEM; + + snod->sqnum = le64_to_cpu(ch->sqnum); + snod->type = ch->node_type; + snod->offs = offs; + snod->len = le32_to_cpu(ch->len); + snod->node = buf; + + switch (ch->node_type) { + case UBIFS_INO_NODE: + case UBIFS_DENT_NODE: + case UBIFS_XENT_NODE: + case UBIFS_DATA_NODE: + case UBIFS_TRUN_NODE: + /* + * The key is in the same place in all keyed + * nodes. + */ + key_read(c, &ino->key, &snod->key); + break; + } + list_add_tail(&snod->list, &sleb->nodes); + sleb->nodes_cnt += 1; + return 0; +} + +/** + * ubifs_scanned_corruption - print information after UBIFS scanned corruption. + * @c: UBIFS file-system description object + * @lnum: LEB number of corruption + * @offs: offset of corruption + * @buf: buffer containing corruption + */ +void ubifs_scanned_corruption(const struct ubifs_info *c, int lnum, int offs, + void *buf) +{ + int len; + + ubifs_err("corrupted data at LEB %d:%d", lnum, offs); + if (dbg_failure_mode) + return; + len = c->leb_size - offs; + if (len > 4096) + len = 4096; + dbg_err("first %d bytes from LEB %d:%d", len, lnum, offs); + print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 4, buf, len, 1); +} + +/** + * ubifs_scan - scan a logical eraseblock. + * @c: UBIFS file-system description object + * @lnum: logical eraseblock number + * @offs: offset to start at (usually zero) + * @sbuf: scan buffer (must be c->leb_size) + * + * This function scans LEB number @lnum and returns complete information about + * its contents. Returns an error code in case of failure. + */ +struct ubifs_scan_leb *ubifs_scan(const struct ubifs_info *c, int lnum, + int offs, void *sbuf) +{ + void *buf = sbuf + offs; + int err, len = c->leb_size - offs; + struct ubifs_scan_leb *sleb; + + sleb = ubifs_start_scan(c, lnum, offs, sbuf); + if (IS_ERR(sleb)) + return sleb; + + while (len >= 8) { + struct ubifs_ch *ch = buf; + int node_len, ret; + + dbg_scan("look at LEB %d:%d (%d bytes left)", + lnum, offs, len); + + cond_resched(); + + ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 0); + + if (ret > 0) { + /* Padding bytes or a valid padding node */ + offs += ret; + buf += ret; + len -= ret; + continue; + } + + if (ret == SCANNED_EMPTY_SPACE) + /* Empty space is checked later */ + break; + + switch (ret) { + case SCANNED_GARBAGE: + dbg_err("garbage"); + goto corrupted; + case SCANNED_A_NODE: + break; + case SCANNED_A_CORRUPT_NODE: + case SCANNED_A_BAD_PAD_NODE: + dbg_err("bad node"); + goto corrupted; + default: + dbg_err("unknown"); + goto corrupted; + } + + err = ubifs_add_snod(c, sleb, buf, offs); + if (err) + goto error; + + node_len = ALIGN(le32_to_cpu(ch->len), 8); + offs += node_len; + buf += node_len; + len -= node_len; + } + + if (offs % c->min_io_size) + goto corrupted; + + ubifs_end_scan(c, sleb, lnum, offs); + + for (; len > 4; offs += 4, buf = buf + 4, len -= 4) + if (*(uint32_t *)buf != 0xffffffff) + break; + for (; len; offs++, buf++, len--) + if (*(uint8_t *)buf != 0xff) { + ubifs_err("corrupt empty space at LEB %d:%d", + lnum, offs); + goto corrupted; + } + + return sleb; + +corrupted: + ubifs_scanned_corruption(c, lnum, offs, buf); + err = -EUCLEAN; +error: + ubifs_err("LEB %d scanning failed", lnum); + ubifs_scan_destroy(sleb); + return ERR_PTR(err); +} + +/** + * ubifs_scan_destroy - destroy LEB scanning information. + * @sleb: scanning information to free + */ +void ubifs_scan_destroy(struct ubifs_scan_leb *sleb) +{ + struct ubifs_scan_node *node; + struct list_head *head; + + head = &sleb->nodes; + while (!list_empty(head)) { + node = list_entry(head->next, struct ubifs_scan_node, list); + list_del(&node->list); + kfree(node); + } + kfree(sleb); +} diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c new file mode 100644 index 0000000..95f2a41 --- /dev/null +++ b/fs/ubifs/super.c @@ -0,0 +1,1189 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file implements UBIFS initialization and VFS superblock operations. Some + * initialization stuff which is rather large and complex is placed at + * corresponding subsystems, but most of it is here. + */ + +#include "ubifs.h" +#include <linux/math64.h> + +#define INODE_LOCKED_MAX 64 + +struct super_block *ubifs_sb; +static struct inode *inodes_locked_down[INODE_LOCKED_MAX]; + +/* shrinker.c */ + +/* List of all UBIFS file-system instances */ +struct list_head ubifs_infos; + +/* linux/fs/super.c */ + +static int sb_set(struct super_block *sb, void *data) +{ + dev_t *dev = data; + + sb->s_dev = *dev; + return 0; +} + +/** + * sget - find or create a superblock + * @type: filesystem type superblock should belong to + * @test: comparison callback + * @set: setup callback + * @data: argument to each of them + */ +struct super_block *sget(struct file_system_type *type, + int (*test)(struct super_block *,void *), + int (*set)(struct super_block *,void *), + void *data) +{ + struct super_block *s = NULL; + int err; + + s = kzalloc(sizeof(struct super_block), GFP_USER); + if (!s) { + err = -ENOMEM; + return ERR_PTR(err); + } + + INIT_LIST_HEAD(&s->s_instances); + INIT_LIST_HEAD(&s->s_inodes); + s->s_time_gran = 1000000000; + + err = set(s, data); + if (err) { + return ERR_PTR(err); + } + s->s_type = type; + strncpy(s->s_id, type->name, sizeof(s->s_id)); + list_add(&s->s_instances, &type->fs_supers); + return s; +} + +/** + * validate_inode - validate inode. + * @c: UBIFS file-system description object + * @inode: the inode to validate + * + * This is a helper function for 'ubifs_iget()' which validates various fields + * of a newly built inode to make sure they contain sane values and prevent + * possible vulnerabilities. Returns zero if the inode is all right and + * a non-zero error code if not. + */ +static int validate_inode(struct ubifs_info *c, const struct inode *inode) +{ + int err; + const struct ubifs_inode *ui = ubifs_inode(inode); + + if (inode->i_size > c->max_inode_sz) { + ubifs_err("inode is too large (%lld)", + (long long)inode->i_size); + return 1; + } + + if (ui->compr_type < 0 || ui->compr_type >= UBIFS_COMPR_TYPES_CNT) { + ubifs_err("unknown compression type %d", ui->compr_type); + return 2; + } + + if (ui->data_len < 0 || ui->data_len > UBIFS_MAX_INO_DATA) + return 4; + + if (!ubifs_compr_present(ui->compr_type)) { + ubifs_warn("inode %lu uses '%s' compression, but it was not " + "compiled in", inode->i_ino, + ubifs_compr_name(ui->compr_type)); + } + + err = dbg_check_dir_size(c, inode); + return err; +} + +struct inode *iget_locked(struct super_block *sb, unsigned long ino) +{ + struct inode *inode; + + inode = (struct inode *)malloc(sizeof(struct ubifs_inode)); + if (inode) { + inode->i_ino = ino; + inode->i_sb = sb; + list_add(&inode->i_sb_list, &sb->s_inodes); + inode->i_state = I_LOCK | I_NEW; + } + + return inode; +} + +int ubifs_iput(struct inode *inode) +{ + list_del_init(&inode->i_sb_list); + + free(inode); + return 0; +} + +/* + * Lock (save) inode in inode array for readback after recovery + */ +void iput(struct inode *inode) +{ + int i; + struct inode *ino; + + /* + * Search end of list + */ + for (i = 0; i < INODE_LOCKED_MAX; i++) { + if (inodes_locked_down[i] == NULL) + break; + } + + if (i >= INODE_LOCKED_MAX) { + ubifs_err("Error, can't lock (save) more inodes while recovery!!!"); + return; + } + + /* + * Allocate and use new inode + */ + ino = (struct inode *)malloc(sizeof(struct ubifs_inode)); + memcpy(ino, inode, sizeof(struct ubifs_inode)); + + /* + * Finally save inode in array + */ + inodes_locked_down[i] = ino; +} + +struct inode *ubifs_iget(struct super_block *sb, unsigned long inum) +{ + int err; + union ubifs_key key; + struct ubifs_ino_node *ino; + struct ubifs_info *c = sb->s_fs_info; + struct inode *inode; + struct ubifs_inode *ui; + int i; + + dbg_gen("inode %lu", inum); + + /* + * U-Boot special handling of locked down inodes via recovery + * e.g. ubifs_recover_size() + */ + for (i = 0; i < INODE_LOCKED_MAX; i++) { + /* + * Exit on last entry (NULL), inode not found in list + */ + if (inodes_locked_down[i] == NULL) + break; + + if (inodes_locked_down[i]->i_ino == inum) { + /* + * We found the locked down inode in our array, + * so just return this pointer instead of creating + * a new one. + */ + return inodes_locked_down[i]; + } + } + + inode = iget_locked(sb, inum); + if (!inode) + return ERR_PTR(-ENOMEM); + if (!(inode->i_state & I_NEW)) + return inode; + ui = ubifs_inode(inode); + + ino = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS); + if (!ino) { + err = -ENOMEM; + goto out; + } + + ino_key_init(c, &key, inode->i_ino); + + err = ubifs_tnc_lookup(c, &key, ino); + if (err) + goto out_ino; + + inode->i_flags |= (S_NOCMTIME | S_NOATIME); + inode->i_nlink = le32_to_cpu(ino->nlink); + inode->i_uid = le32_to_cpu(ino->uid); + inode->i_gid = le32_to_cpu(ino->gid); + inode->i_atime.tv_sec = (int64_t)le64_to_cpu(ino->atime_sec); + inode->i_atime.tv_nsec = le32_to_cpu(ino->atime_nsec); + inode->i_mtime.tv_sec = (int64_t)le64_to_cpu(ino->mtime_sec); + inode->i_mtime.tv_nsec = le32_to_cpu(ino->mtime_nsec); + inode->i_ctime.tv_sec = (int64_t)le64_to_cpu(ino->ctime_sec); + inode->i_ctime.tv_nsec = le32_to_cpu(ino->ctime_nsec); + inode->i_mode = le32_to_cpu(ino->mode); + inode->i_size = le64_to_cpu(ino->size); + + ui->data_len = le32_to_cpu(ino->data_len); + ui->flags = le32_to_cpu(ino->flags); + ui->compr_type = le16_to_cpu(ino->compr_type); + ui->creat_sqnum = le64_to_cpu(ino->creat_sqnum); + ui->synced_i_size = ui->ui_size = inode->i_size; + + err = validate_inode(c, inode); + if (err) + goto out_invalid; + + if ((inode->i_mode & S_IFMT) == S_IFLNK) { + if (ui->data_len <= 0 || ui->data_len > UBIFS_MAX_INO_DATA) { + err = 12; + goto out_invalid; + } + ui->data = kmalloc(ui->data_len + 1, GFP_NOFS); + if (!ui->data) { + err = -ENOMEM; + goto out_ino; + } + memcpy(ui->data, ino->data, ui->data_len); + ((char *)ui->data)[ui->data_len] = '\0'; + } + + kfree(ino); + inode->i_state &= ~(I_LOCK | I_NEW); + return inode; + +out_invalid: + ubifs_err("inode %lu validation failed, error %d", inode->i_ino, err); + dbg_dump_node(c, ino); + dbg_dump_inode(c, inode); + err = -EINVAL; +out_ino: + kfree(ino); +out: + ubifs_err("failed to read inode %lu, error %d", inode->i_ino, err); + return ERR_PTR(err); +} + +/** + * init_constants_early - initialize UBIFS constants. + * @c: UBIFS file-system description object + * + * This function initialize UBIFS constants which do not need the superblock to + * be read. It also checks that the UBI volume satisfies basic UBIFS + * requirements. Returns zero in case of success and a negative error code in + * case of failure. + */ +static int init_constants_early(struct ubifs_info *c) +{ + if (c->vi.corrupted) { + ubifs_warn("UBI volume is corrupted - read-only mode"); + c->ro_media = 1; + } + + if (c->di.ro_mode) { + ubifs_msg("read-only UBI device"); + c->ro_media = 1; + } + + if (c->vi.vol_type == UBI_STATIC_VOLUME) { + ubifs_msg("static UBI volume - read-only mode"); + c->ro_media = 1; + } + + c->leb_cnt = c->vi.size; + c->leb_size = c->vi.usable_leb_size; + c->half_leb_size = c->leb_size / 2; + c->min_io_size = c->di.min_io_size; + c->min_io_shift = fls(c->min_io_size) - 1; + + if (c->leb_size < UBIFS_MIN_LEB_SZ) { + ubifs_err("too small LEBs (%d bytes), min. is %d bytes", + c->leb_size, UBIFS_MIN_LEB_SZ); + return -EINVAL; + } + + if (c->leb_cnt < UBIFS_MIN_LEB_CNT) { + ubifs_err("too few LEBs (%d), min. is %d", + c->leb_cnt, UBIFS_MIN_LEB_CNT); + return -EINVAL; + } + + if (!is_power_of_2(c->min_io_size)) { + ubifs_err("bad min. I/O size %d", c->min_io_size); + return -EINVAL; + } + + /* + * UBIFS aligns all node to 8-byte boundary, so to make function in + * io.c simpler, assume minimum I/O unit size to be 8 bytes if it is + * less than 8. + */ + if (c->min_io_size < 8) { + c->min_io_size = 8; + c->min_io_shift = 3; + } + + c->ref_node_alsz = ALIGN(UBIFS_REF_NODE_SZ, c->min_io_size); + c->mst_node_alsz = ALIGN(UBIFS_MST_NODE_SZ, c->min_io_size); + + /* + * Initialize node length ranges which are mostly needed for node + * length validation. + */ + c->ranges[UBIFS_PAD_NODE].len = UBIFS_PAD_NODE_SZ; + c->ranges[UBIFS_SB_NODE].len = UBIFS_SB_NODE_SZ; + c->ranges[UBIFS_MST_NODE].len = UBIFS_MST_NODE_SZ; + c->ranges[UBIFS_REF_NODE].len = UBIFS_REF_NODE_SZ; + c->ranges[UBIFS_TRUN_NODE].len = UBIFS_TRUN_NODE_SZ; + c->ranges[UBIFS_CS_NODE].len = UBIFS_CS_NODE_SZ; + + c->ranges[UBIFS_INO_NODE].min_len = UBIFS_INO_NODE_SZ; + c->ranges[UBIFS_INO_NODE].max_len = UBIFS_MAX_INO_NODE_SZ; + c->ranges[UBIFS_ORPH_NODE].min_len = + UBIFS_ORPH_NODE_SZ + sizeof(__le64); + c->ranges[UBIFS_ORPH_NODE].max_len = c->leb_size; + c->ranges[UBIFS_DENT_NODE].min_len = UBIFS_DENT_NODE_SZ; + c->ranges[UBIFS_DENT_NODE].max_len = UBIFS_MAX_DENT_NODE_SZ; + c->ranges[UBIFS_XENT_NODE].min_len = UBIFS_XENT_NODE_SZ; + c->ranges[UBIFS_XENT_NODE].max_len = UBIFS_MAX_XENT_NODE_SZ; + c->ranges[UBIFS_DATA_NODE].min_len = UBIFS_DATA_NODE_SZ; + c->ranges[UBIFS_DATA_NODE].max_len = UBIFS_MAX_DATA_NODE_SZ; + /* + * Minimum indexing node size is amended later when superblock is + * read and the key length is known. + */ + c->ranges[UBIFS_IDX_NODE].min_len = UBIFS_IDX_NODE_SZ + UBIFS_BRANCH_SZ; + /* + * Maximum indexing node size is amended later when superblock is + * read and the fanout is known. + */ + c->ranges[UBIFS_IDX_NODE].max_len = INT_MAX; + + /* + * Initialize dead and dark LEB space watermarks. See gc.c for comments + * about these values. + */ + c->dead_wm = ALIGN(MIN_WRITE_SZ, c->min_io_size); + c->dark_wm = ALIGN(UBIFS_MAX_NODE_SZ, c->min_io_size); + + /* + * Calculate how many bytes would be wasted at the end of LEB if it was + * fully filled with data nodes of maximum size. This is used in + * calculations when reporting free space. + */ + c->leb_overhead = c->leb_size % UBIFS_MAX_DATA_NODE_SZ; + + return 0; +} + +/* + * init_constants_sb - initialize UBIFS constants. + * @c: UBIFS file-system description object + * + * This is a helper function which initializes various UBIFS constants after + * the superblock has been read. It also checks various UBIFS parameters and + * makes sure they are all right. Returns zero in case of success and a + * negative error code in case of failure. + */ +static int init_constants_sb(struct ubifs_info *c) +{ + int tmp, err; + long long tmp64; + + c->main_bytes = (long long)c->main_lebs * c->leb_size; + c->max_znode_sz = sizeof(struct ubifs_znode) + + c->fanout * sizeof(struct ubifs_zbranch); + + tmp = ubifs_idx_node_sz(c, 1); + c->ranges[UBIFS_IDX_NODE].min_len = tmp; + c->min_idx_node_sz = ALIGN(tmp, 8); + + tmp = ubifs_idx_node_sz(c, c->fanout); + c->ranges[UBIFS_IDX_NODE].max_len = tmp; + c->max_idx_node_sz = ALIGN(tmp, 8); + + /* Make sure LEB size is large enough to fit full commit */ + tmp = UBIFS_CS_NODE_SZ + UBIFS_REF_NODE_SZ * c->jhead_cnt; + tmp = ALIGN(tmp, c->min_io_size); + if (tmp > c->leb_size) { + dbg_err("too small LEB size %d, at least %d needed", + c->leb_size, tmp); + return -EINVAL; + } + + /* + * Make sure that the log is large enough to fit reference nodes for + * all buds plus one reserved LEB. + */ + tmp64 = c->max_bud_bytes + c->leb_size - 1; + c->max_bud_cnt = div_u64(tmp64, c->leb_size); + tmp = (c->ref_node_alsz * c->max_bud_cnt + c->leb_size - 1); + tmp /= c->leb_size; + tmp += 1; + if (c->log_lebs < tmp) { + dbg_err("too small log %d LEBs, required min. %d LEBs", + c->log_lebs, tmp); + return -EINVAL; + } + + /* + * When budgeting we assume worst-case scenarios when the pages are not + * be compressed and direntries are of the maximum size. + * + * Note, data, which may be stored in inodes is budgeted separately, so + * it is not included into 'c->inode_budget'. + */ + c->page_budget = UBIFS_MAX_DATA_NODE_SZ * UBIFS_BLOCKS_PER_PAGE; + c->inode_budget = UBIFS_INO_NODE_SZ; + c->dent_budget = UBIFS_MAX_DENT_NODE_SZ; + + /* + * When the amount of flash space used by buds becomes + * 'c->max_bud_bytes', UBIFS just blocks all writers and starts commit. + * The writers are unblocked when the commit is finished. To avoid + * writers to be blocked UBIFS initiates background commit in advance, + * when number of bud bytes becomes above the limit defined below. + */ + c->bg_bud_bytes = (c->max_bud_bytes * 13) >> 4; + + /* + * Ensure minimum journal size. All the bytes in the journal heads are + * considered to be used, when calculating the current journal usage. + * Consequently, if the journal is too small, UBIFS will treat it as + * always full. + */ + tmp64 = (long long)(c->jhead_cnt + 1) * c->leb_size + 1; + if (c->bg_bud_bytes < tmp64) + c->bg_bud_bytes = tmp64; + if (c->max_bud_bytes < tmp64 + c->leb_size) + c->max_bud_bytes = tmp64 + c->leb_size; + + err = ubifs_calc_lpt_geom(c); + if (err) + return err; + + return 0; +} + +/* + * init_constants_master - initialize UBIFS constants. + * @c: UBIFS file-system description object + * + * This is a helper function which initializes various UBIFS constants after + * the master node has been read. It also checks various UBIFS parameters and + * makes sure they are all right. + */ +static void init_constants_master(struct ubifs_info *c) +{ + long long tmp64; + + c->min_idx_lebs = ubifs_calc_min_idx_lebs(c); + + /* + * Calculate total amount of FS blocks. This number is not used + * internally because it does not make much sense for UBIFS, but it is + * necessary to report something for the 'statfs()' call. + * + * Subtract the LEB reserved for GC, the LEB which is reserved for + * deletions, minimum LEBs for the index, and assume only one journal + * head is available. + */ + tmp64 = c->main_lebs - 1 - 1 - MIN_INDEX_LEBS - c->jhead_cnt + 1; + tmp64 *= (long long)c->leb_size - c->leb_overhead; + tmp64 = ubifs_reported_space(c, tmp64); + c->block_cnt = tmp64 >> UBIFS_BLOCK_SHIFT; +} + +/** + * free_orphans - free orphans. + * @c: UBIFS file-system description object + */ +static void free_orphans(struct ubifs_info *c) +{ + struct ubifs_orphan *orph; + + while (c->orph_dnext) { + orph = c->orph_dnext; + c->orph_dnext = orph->dnext; + list_del(&orph->list); + kfree(orph); + } + + while (!list_empty(&c->orph_list)) { + orph = list_entry(c->orph_list.next, struct ubifs_orphan, list); + list_del(&orph->list); + kfree(orph); + dbg_err("orphan list not empty at unmount"); + } + + vfree(c->orph_buf); + c->orph_buf = NULL; +} + +/** + * check_volume_empty - check if the UBI volume is empty. + * @c: UBIFS file-system description object + * + * This function checks if the UBIFS volume is empty by looking if its LEBs are + * mapped or not. The result of checking is stored in the @c->empty variable. + * Returns zero in case of success and a negative error code in case of + * failure. + */ +static int check_volume_empty(struct ubifs_info *c) +{ + int lnum, err; + + c->empty = 1; + for (lnum = 0; lnum < c->leb_cnt; lnum++) { + err = ubi_is_mapped(c->ubi, lnum); + if (unlikely(err < 0)) + return err; + if (err == 1) { + c->empty = 0; + break; + } + + cond_resched(); + } + + return 0; +} + +/** + * mount_ubifs - mount UBIFS file-system. + * @c: UBIFS file-system description object + * + * This function mounts UBIFS file system. Returns zero in case of success and + * a negative error code in case of failure. + * + * Note, the function does not de-allocate resources it it fails half way + * through, and the caller has to do this instead. + */ +static int mount_ubifs(struct ubifs_info *c) +{ + struct super_block *sb = c->vfs_sb; + int err, mounted_read_only = (sb->s_flags & MS_RDONLY); + long long x; + size_t sz; + + err = init_constants_early(c); + if (err) + return err; + + err = ubifs_debugging_init(c); + if (err) + return err; + + err = check_volume_empty(c); + if (err) + goto out_free; + + if (c->empty && (mounted_read_only || c->ro_media)) { + /* + * This UBI volume is empty, and read-only, or the file system + * is mounted read-only - we cannot format it. + */ + ubifs_err("can't format empty UBI volume: read-only %s", + c->ro_media ? "UBI volume" : "mount"); + err = -EROFS; + goto out_free; + } + + if (c->ro_media && !mounted_read_only) { + ubifs_err("cannot mount read-write - read-only media"); + err = -EROFS; + goto out_free; + } + + /* + * The requirement for the buffer is that it should fit indexing B-tree + * height amount of integers. We assume the height if the TNC tree will + * never exceed 64. + */ + err = -ENOMEM; + c->bottom_up_buf = kmalloc(BOTTOM_UP_HEIGHT * sizeof(int), GFP_KERNEL); + if (!c->bottom_up_buf) + goto out_free; + + c->sbuf = vmalloc(c->leb_size); + if (!c->sbuf) + goto out_free; + + /* + * We have to check all CRCs, even for data nodes, when we mount the FS + * (specifically, when we are replaying). + */ + c->always_chk_crc = 1; + + err = ubifs_read_superblock(c); + if (err) + goto out_free; + + /* + * Make sure the compressor which is set as default in the superblock + * or overridden by mount options is actually compiled in. + */ + if (!ubifs_compr_present(c->default_compr)) { + ubifs_err("'compressor \"%s\" is not compiled in", + ubifs_compr_name(c->default_compr)); + goto out_free; + } + + dbg_failure_mode_registration(c); + + err = init_constants_sb(c); + if (err) + goto out_free; + + sz = ALIGN(c->max_idx_node_sz, c->min_io_size); + sz = ALIGN(sz + c->max_idx_node_sz, c->min_io_size); + c->cbuf = kmalloc(sz, GFP_NOFS); + if (!c->cbuf) { + err = -ENOMEM; + goto out_free; + } + + sprintf(c->bgt_name, BGT_NAME_PATTERN, c->vi.ubi_num, c->vi.vol_id); + + err = ubifs_read_master(c); + if (err) + goto out_master; + + init_constants_master(c); + + if ((c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY)) != 0) { + ubifs_msg("recovery needed"); + c->need_recovery = 1; + } + + err = ubifs_lpt_init(c, 1, !mounted_read_only); + if (err) + goto out_lpt; + + err = dbg_check_idx_size(c, c->old_idx_sz); + if (err) + goto out_lpt; + + err = ubifs_replay_journal(c); + if (err) + goto out_journal; + + err = ubifs_mount_orphans(c, c->need_recovery, mounted_read_only); + if (err) + goto out_orphans; + + if (c->need_recovery) { + err = ubifs_recover_size(c); + if (err) + goto out_orphans; + } + + spin_lock(&ubifs_infos_lock); + list_add_tail(&c->infos_list, &ubifs_infos); + spin_unlock(&ubifs_infos_lock); + + if (c->need_recovery) { + if (mounted_read_only) + ubifs_msg("recovery deferred"); + else { + c->need_recovery = 0; + ubifs_msg("recovery completed"); + } + } + + err = dbg_check_filesystem(c); + if (err) + goto out_infos; + + c->always_chk_crc = 0; + + ubifs_msg("mounted UBI device %d, volume %d, name \"%s\"", + c->vi.ubi_num, c->vi.vol_id, c->vi.name); + if (mounted_read_only) + ubifs_msg("mounted read-only"); + x = (long long)c->main_lebs * c->leb_size; + ubifs_msg("file system size: %lld bytes (%lld KiB, %lld MiB, %d " + "LEBs)", x, x >> 10, x >> 20, c->main_lebs); + x = (long long)c->log_lebs * c->leb_size + c->max_bud_bytes; + ubifs_msg("journal size: %lld bytes (%lld KiB, %lld MiB, %d " + "LEBs)", x, x >> 10, x >> 20, c->log_lebs + c->max_bud_cnt); + ubifs_msg("media format: %d (latest is %d)", + c->fmt_version, UBIFS_FORMAT_VERSION); + ubifs_msg("default compressor: %s", ubifs_compr_name(c->default_compr)); + ubifs_msg("reserved for root: %llu bytes (%llu KiB)", + c->report_rp_size, c->report_rp_size >> 10); + + dbg_msg("compiled on: " __DATE__ " at " __TIME__); + dbg_msg("min. I/O unit size: %d bytes", c->min_io_size); + dbg_msg("LEB size: %d bytes (%d KiB)", + c->leb_size, c->leb_size >> 10); + dbg_msg("data journal heads: %d", + c->jhead_cnt - NONDATA_JHEADS_CNT); + dbg_msg("UUID: %02X%02X%02X%02X-%02X%02X" + "-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X", + c->uuid[0], c->uuid[1], c->uuid[2], c->uuid[3], + c->uuid[4], c->uuid[5], c->uuid[6], c->uuid[7], + c->uuid[8], c->uuid[9], c->uuid[10], c->uuid[11], + c->uuid[12], c->uuid[13], c->uuid[14], c->uuid[15]); + dbg_msg("big_lpt %d", c->big_lpt); + dbg_msg("log LEBs: %d (%d - %d)", + c->log_lebs, UBIFS_LOG_LNUM, c->log_last); + dbg_msg("LPT area LEBs: %d (%d - %d)", + c->lpt_lebs, c->lpt_first, c->lpt_last); + dbg_msg("orphan area LEBs: %d (%d - %d)", + c->orph_lebs, c->orph_first, c->orph_last); + dbg_msg("main area LEBs: %d (%d - %d)", + c->main_lebs, c->main_first, c->leb_cnt - 1); + dbg_msg("index LEBs: %d", c->lst.idx_lebs); + dbg_msg("total index bytes: %lld (%lld KiB, %lld MiB)", + c->old_idx_sz, c->old_idx_sz >> 10, c->old_idx_sz >> 20); + dbg_msg("key hash type: %d", c->key_hash_type); + dbg_msg("tree fanout: %d", c->fanout); + dbg_msg("reserved GC LEB: %d", c->gc_lnum); + dbg_msg("first main LEB: %d", c->main_first); + dbg_msg("max. znode size %d", c->max_znode_sz); + dbg_msg("max. index node size %d", c->max_idx_node_sz); + dbg_msg("node sizes: data %zu, inode %zu, dentry %zu", + UBIFS_DATA_NODE_SZ, UBIFS_INO_NODE_SZ, UBIFS_DENT_NODE_SZ); + dbg_msg("node sizes: trun %zu, sb %zu, master %zu", + UBIFS_TRUN_NODE_SZ, UBIFS_SB_NODE_SZ, UBIFS_MST_NODE_SZ); + dbg_msg("node sizes: ref %zu, cmt. start %zu, orph %zu", + UBIFS_REF_NODE_SZ, UBIFS_CS_NODE_SZ, UBIFS_ORPH_NODE_SZ); + dbg_msg("max. node sizes: data %zu, inode %zu dentry %zu", + UBIFS_MAX_DATA_NODE_SZ, UBIFS_MAX_INO_NODE_SZ, + UBIFS_MAX_DENT_NODE_SZ); + dbg_msg("dead watermark: %d", c->dead_wm); + dbg_msg("dark watermark: %d", c->dark_wm); + dbg_msg("LEB overhead: %d", c->leb_overhead); + x = (long long)c->main_lebs * c->dark_wm; + dbg_msg("max. dark space: %lld (%lld KiB, %lld MiB)", + x, x >> 10, x >> 20); + dbg_msg("maximum bud bytes: %lld (%lld KiB, %lld MiB)", + c->max_bud_bytes, c->max_bud_bytes >> 10, + c->max_bud_bytes >> 20); + dbg_msg("BG commit bud bytes: %lld (%lld KiB, %lld MiB)", + c->bg_bud_bytes, c->bg_bud_bytes >> 10, + c->bg_bud_bytes >> 20); + dbg_msg("current bud bytes %lld (%lld KiB, %lld MiB)", + c->bud_bytes, c->bud_bytes >> 10, c->bud_bytes >> 20); + dbg_msg("max. seq. number: %llu", c->max_sqnum); + dbg_msg("commit number: %llu", c->cmt_no); + + return 0; + +out_infos: + spin_lock(&ubifs_infos_lock); + list_del(&c->infos_list); + spin_unlock(&ubifs_infos_lock); +out_orphans: + free_orphans(c); +out_journal: +out_lpt: + ubifs_lpt_free(c, 0); +out_master: + kfree(c->mst_node); + kfree(c->rcvrd_mst_node); + if (c->bgt) + kthread_stop(c->bgt); + kfree(c->cbuf); +out_free: + vfree(c->ileb_buf); + vfree(c->sbuf); + kfree(c->bottom_up_buf); + ubifs_debugging_exit(c); + return err; +} + +/** + * ubifs_umount - un-mount UBIFS file-system. + * @c: UBIFS file-system description object + * + * Note, this function is called to free allocated resourced when un-mounting, + * as well as free resources when an error occurred while we were half way + * through mounting (error path cleanup function). So it has to make sure the + * resource was actually allocated before freeing it. + */ +static void ubifs_umount(struct ubifs_info *c) +{ + dbg_gen("un-mounting UBI device %d, volume %d", c->vi.ubi_num, + c->vi.vol_id); + + spin_lock(&ubifs_infos_lock); + list_del(&c->infos_list); + spin_unlock(&ubifs_infos_lock); + + if (c->bgt) + kthread_stop(c->bgt); + + free_orphans(c); + ubifs_lpt_free(c, 0); + + kfree(c->cbuf); + kfree(c->rcvrd_mst_node); + kfree(c->mst_node); + vfree(c->ileb_buf); + vfree(c->sbuf); + kfree(c->bottom_up_buf); + ubifs_debugging_exit(c); + + /* Finally free U-Boot's global copy of superblock */ + free(ubifs_sb->s_fs_info); + free(ubifs_sb); +} + +/** + * open_ubi - parse UBI device name string and open the UBI device. + * @name: UBI volume name + * @mode: UBI volume open mode + * + * There are several ways to specify UBI volumes when mounting UBIFS: + * o ubiX_Y - UBI device number X, volume Y; + * o ubiY - UBI device number 0, volume Y; + * o ubiX:NAME - mount UBI device X, volume with name NAME; + * o ubi:NAME - mount UBI device 0, volume with name NAME. + * + * Alternative '!' separator may be used instead of ':' (because some shells + * like busybox may interpret ':' as an NFS host name separator). This function + * returns ubi volume object in case of success and a negative error code in + * case of failure. + */ +static struct ubi_volume_desc *open_ubi(const char *name, int mode) +{ + int dev, vol; + char *endptr; + + if (name[0] != 'u' || name[1] != 'b' || name[2] != 'i') + return ERR_PTR(-EINVAL); + + /* ubi:NAME method */ + if ((name[3] == ':' || name[3] == '!') && name[4] != '\0') + return ubi_open_volume_nm(0, name + 4, mode); + + if (!isdigit(name[3])) + return ERR_PTR(-EINVAL); + + dev = simple_strtoul(name + 3, &endptr, 0); + + /* ubiY method */ + if (*endptr == '\0') + return ubi_open_volume(0, dev, mode); + + /* ubiX_Y method */ + if (*endptr == '_' && isdigit(endptr[1])) { + vol = simple_strtoul(endptr + 1, &endptr, 0); + if (*endptr != '\0') + return ERR_PTR(-EINVAL); + return ubi_open_volume(dev, vol, mode); + } + + /* ubiX:NAME method */ + if ((*endptr == ':' || *endptr == '!') && endptr[1] != '\0') + return ubi_open_volume_nm(dev, ++endptr, mode); + + return ERR_PTR(-EINVAL); +} + +static int ubifs_fill_super(struct super_block *sb, void *data, int silent) +{ + struct ubi_volume_desc *ubi = sb->s_fs_info; + struct ubifs_info *c; + struct inode *root; + int err; + + c = kzalloc(sizeof(struct ubifs_info), GFP_KERNEL); + if (!c) + return -ENOMEM; + + spin_lock_init(&c->cnt_lock); + spin_lock_init(&c->cs_lock); + spin_lock_init(&c->buds_lock); + spin_lock_init(&c->space_lock); + spin_lock_init(&c->orphan_lock); + init_rwsem(&c->commit_sem); + mutex_init(&c->lp_mutex); + mutex_init(&c->tnc_mutex); + mutex_init(&c->log_mutex); + mutex_init(&c->mst_mutex); + mutex_init(&c->umount_mutex); + init_waitqueue_head(&c->cmt_wq); + c->buds = RB_ROOT; + c->old_idx = RB_ROOT; + c->size_tree = RB_ROOT; + c->orph_tree = RB_ROOT; + INIT_LIST_HEAD(&c->infos_list); + INIT_LIST_HEAD(&c->idx_gc); + INIT_LIST_HEAD(&c->replay_list); + INIT_LIST_HEAD(&c->replay_buds); + INIT_LIST_HEAD(&c->uncat_list); + INIT_LIST_HEAD(&c->empty_list); + INIT_LIST_HEAD(&c->freeable_list); + INIT_LIST_HEAD(&c->frdi_idx_list); + INIT_LIST_HEAD(&c->unclean_leb_list); + INIT_LIST_HEAD(&c->old_buds); + INIT_LIST_HEAD(&c->orph_list); + INIT_LIST_HEAD(&c->orph_new); + + c->highest_inum = UBIFS_FIRST_INO; + c->lhead_lnum = c->ltail_lnum = UBIFS_LOG_LNUM; + + ubi_get_volume_info(ubi, &c->vi); + ubi_get_device_info(c->vi.ubi_num, &c->di); + + /* Re-open the UBI device in read-write mode */ + c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READONLY); + if (IS_ERR(c->ubi)) { + err = PTR_ERR(c->ubi); + goto out_free; + } + + c->vfs_sb = sb; + + sb->s_fs_info = c; + sb->s_magic = UBIFS_SUPER_MAGIC; + sb->s_blocksize = UBIFS_BLOCK_SIZE; + sb->s_blocksize_bits = UBIFS_BLOCK_SHIFT; + sb->s_dev = c->vi.cdev; + sb->s_maxbytes = c->max_inode_sz = key_max_inode_size(c); + if (c->max_inode_sz > MAX_LFS_FILESIZE) + sb->s_maxbytes = c->max_inode_sz = MAX_LFS_FILESIZE; + + mutex_lock(&c->umount_mutex); + err = mount_ubifs(c); + if (err) { + ubifs_assert(err < 0); + goto out_unlock; + } + + /* Read the root inode */ + root = ubifs_iget(sb, UBIFS_ROOT_INO); + if (IS_ERR(root)) { + err = PTR_ERR(root); + goto out_umount; + } + + sb->s_root = NULL; + + mutex_unlock(&c->umount_mutex); + return 0; + +out_umount: + ubifs_umount(c); +out_unlock: + mutex_unlock(&c->umount_mutex); + ubi_close_volume(c->ubi); +out_free: + kfree(c); + return err; +} + +static int sb_test(struct super_block *sb, void *data) +{ + dev_t *dev = data; + + return sb->s_dev == *dev; +} + +static int ubifs_get_sb(struct file_system_type *fs_type, int flags, + const char *name, void *data, struct vfsmount *mnt) +{ + struct ubi_volume_desc *ubi; + struct ubi_volume_info vi; + struct super_block *sb; + int err; + + dbg_gen("name %s, flags %#x", name, flags); + + /* + * Get UBI device number and volume ID. Mount it read-only so far + * because this might be a new mount point, and UBI allows only one + * read-write user at a time. + */ + ubi = open_ubi(name, UBI_READONLY); + if (IS_ERR(ubi)) { + ubifs_err("cannot open \"%s\", error %d", + name, (int)PTR_ERR(ubi)); + return PTR_ERR(ubi); + } + ubi_get_volume_info(ubi, &vi); + + dbg_gen("opened ubi%d_%d", vi.ubi_num, vi.vol_id); + + sb = sget(fs_type, &sb_test, &sb_set, &vi.cdev); + if (IS_ERR(sb)) { + err = PTR_ERR(sb); + goto out_close; + } + + if (sb->s_root) { + /* A new mount point for already mounted UBIFS */ + dbg_gen("this ubi volume is already mounted"); + if ((flags ^ sb->s_flags) & MS_RDONLY) { + err = -EBUSY; + goto out_deact; + } + } else { + sb->s_flags = flags; + /* + * Pass 'ubi' to 'fill_super()' in sb->s_fs_info where it is + * replaced by 'c'. + */ + sb->s_fs_info = ubi; + err = ubifs_fill_super(sb, data, flags & MS_SILENT ? 1 : 0); + if (err) + goto out_deact; + /* We do not support atime */ + sb->s_flags |= MS_ACTIVE | MS_NOATIME; + } + + /* 'fill_super()' opens ubi again so we must close it here */ + ubi_close_volume(ubi); + + ubifs_sb = sb; + return 0; + +out_deact: + up_write(&sb->s_umount); +out_close: + ubi_close_volume(ubi); + return err; +} + +int __init ubifs_init(void) +{ + int err; + + BUILD_BUG_ON(sizeof(struct ubifs_ch) != 24); + + /* Make sure node sizes are 8-byte aligned */ + BUILD_BUG_ON(UBIFS_CH_SZ & 7); + BUILD_BUG_ON(UBIFS_INO_NODE_SZ & 7); + BUILD_BUG_ON(UBIFS_DENT_NODE_SZ & 7); + BUILD_BUG_ON(UBIFS_XENT_NODE_SZ & 7); + BUILD_BUG_ON(UBIFS_DATA_NODE_SZ & 7); + BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ & 7); + BUILD_BUG_ON(UBIFS_SB_NODE_SZ & 7); + BUILD_BUG_ON(UBIFS_MST_NODE_SZ & 7); + BUILD_BUG_ON(UBIFS_REF_NODE_SZ & 7); + BUILD_BUG_ON(UBIFS_CS_NODE_SZ & 7); + BUILD_BUG_ON(UBIFS_ORPH_NODE_SZ & 7); + + BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ & 7); + BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ & 7); + BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ & 7); + BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ & 7); + BUILD_BUG_ON(UBIFS_MAX_NODE_SZ & 7); + BUILD_BUG_ON(MIN_WRITE_SZ & 7); + + /* Check min. node size */ + BUILD_BUG_ON(UBIFS_INO_NODE_SZ < MIN_WRITE_SZ); + BUILD_BUG_ON(UBIFS_DENT_NODE_SZ < MIN_WRITE_SZ); + BUILD_BUG_ON(UBIFS_XENT_NODE_SZ < MIN_WRITE_SZ); + BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ < MIN_WRITE_SZ); + + BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ > UBIFS_MAX_NODE_SZ); + BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ > UBIFS_MAX_NODE_SZ); + BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ > UBIFS_MAX_NODE_SZ); + BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ > UBIFS_MAX_NODE_SZ); + + /* Defined node sizes */ + BUILD_BUG_ON(UBIFS_SB_NODE_SZ != 4096); + BUILD_BUG_ON(UBIFS_MST_NODE_SZ != 512); + BUILD_BUG_ON(UBIFS_INO_NODE_SZ != 160); + BUILD_BUG_ON(UBIFS_REF_NODE_SZ != 64); + + /* + * We use 2 bit wide bit-fields to store compression type, which should + * be amended if more compressors are added. The bit-fields are: + * @compr_type in 'struct ubifs_inode', @default_compr in + * 'struct ubifs_info' and @compr_type in 'struct ubifs_mount_opts'. + */ + BUILD_BUG_ON(UBIFS_COMPR_TYPES_CNT > 4); + + /* + * We require that PAGE_CACHE_SIZE is greater-than-or-equal-to + * UBIFS_BLOCK_SIZE. It is assumed that both are powers of 2. + */ + if (PAGE_CACHE_SIZE < UBIFS_BLOCK_SIZE) { + ubifs_err("VFS page cache size is %u bytes, but UBIFS requires" + " at least 4096 bytes", + (unsigned int)PAGE_CACHE_SIZE); + return -EINVAL; + } + + err = -ENOMEM; + + err = ubifs_compressors_init(); + if (err) + goto out_shrinker; + + return 0; + +out_shrinker: + return err; +} + +/* + * ubifsmount... + */ + +static struct file_system_type ubifs_fs_type = { + .name = "ubifs", + .owner = THIS_MODULE, + .get_sb = ubifs_get_sb, +}; + +int ubifs_mount(char *vol_name) +{ + int flags; + char name[80] = "ubi:"; + void *data; + struct vfsmount *mnt; + int ret; + struct ubifs_info *c; + + /* + * First unmount if allready mounted + */ + if (ubifs_sb) + ubifs_umount(ubifs_sb->s_fs_info); + + INIT_LIST_HEAD(&ubifs_infos); + + /* + * Mount in read-only mode + */ + flags = MS_RDONLY; + strcat(name, vol_name); + data = NULL; + mnt = NULL; + ret = ubifs_get_sb(&ubifs_fs_type, flags, name, data, mnt); + if (ret) { + printf("Error reading superblock on volume '%s'!\n", name); + return -1; + } + + c = ubifs_sb->s_fs_info; + ubi_close_volume(c->ubi); + + return 0; +} diff --git a/fs/ubifs/tnc.c b/fs/ubifs/tnc.c new file mode 100644 index 0000000..ccda938 --- /dev/null +++ b/fs/ubifs/tnc.c @@ -0,0 +1,2767 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file implements TNC (Tree Node Cache) which caches indexing nodes of + * the UBIFS B-tree. + * + * At the moment the locking rules of the TNC tree are quite simple and + * straightforward. We just have a mutex and lock it when we traverse the + * tree. If a znode is not in memory, we read it from flash while still having + * the mutex locked. + */ + +#include "ubifs.h" + +/* + * Returned codes of 'matches_name()' and 'fallible_matches_name()' functions. + * @NAME_LESS: name corresponding to the first argument is less than second + * @NAME_MATCHES: names match + * @NAME_GREATER: name corresponding to the second argument is greater than + * first + * @NOT_ON_MEDIA: node referred by zbranch does not exist on the media + * + * These constants were introduce to improve readability. + */ +enum { + NAME_LESS = 0, + NAME_MATCHES = 1, + NAME_GREATER = 2, + NOT_ON_MEDIA = 3, +}; + +/** + * insert_old_idx - record an index node obsoleted since the last commit start. + * @c: UBIFS file-system description object + * @lnum: LEB number of obsoleted index node + * @offs: offset of obsoleted index node + * + * Returns %0 on success, and a negative error code on failure. + * + * For recovery, there must always be a complete intact version of the index on + * flash at all times. That is called the "old index". It is the index as at the + * time of the last successful commit. Many of the index nodes in the old index + * may be dirty, but they must not be erased until the next successful commit + * (at which point that index becomes the old index). + * + * That means that the garbage collection and the in-the-gaps method of + * committing must be able to determine if an index node is in the old index. + * Most of the old index nodes can be found by looking up the TNC using the + * 'lookup_znode()' function. However, some of the old index nodes may have + * been deleted from the current index or may have been changed so much that + * they cannot be easily found. In those cases, an entry is added to an RB-tree. + * That is what this function does. The RB-tree is ordered by LEB number and + * offset because they uniquely identify the old index node. + */ +static int insert_old_idx(struct ubifs_info *c, int lnum, int offs) +{ + struct ubifs_old_idx *old_idx, *o; + struct rb_node **p, *parent = NULL; + + old_idx = kmalloc(sizeof(struct ubifs_old_idx), GFP_NOFS); + if (unlikely(!old_idx)) + return -ENOMEM; + old_idx->lnum = lnum; + old_idx->offs = offs; + + p = &c->old_idx.rb_node; + while (*p) { + parent = *p; + o = rb_entry(parent, struct ubifs_old_idx, rb); + if (lnum < o->lnum) + p = &(*p)->rb_left; + else if (lnum > o->lnum) + p = &(*p)->rb_right; + else if (offs < o->offs) + p = &(*p)->rb_left; + else if (offs > o->offs) + p = &(*p)->rb_right; + else { + ubifs_err("old idx added twice!"); + kfree(old_idx); + return 0; + } + } + rb_link_node(&old_idx->rb, parent, p); + rb_insert_color(&old_idx->rb, &c->old_idx); + return 0; +} + +/** + * insert_old_idx_znode - record a znode obsoleted since last commit start. + * @c: UBIFS file-system description object + * @znode: znode of obsoleted index node + * + * Returns %0 on success, and a negative error code on failure. + */ +int insert_old_idx_znode(struct ubifs_info *c, struct ubifs_znode *znode) +{ + if (znode->parent) { + struct ubifs_zbranch *zbr; + + zbr = &znode->parent->zbranch[znode->iip]; + if (zbr->len) + return insert_old_idx(c, zbr->lnum, zbr->offs); + } else + if (c->zroot.len) + return insert_old_idx(c, c->zroot.lnum, + c->zroot.offs); + return 0; +} + +/** + * ins_clr_old_idx_znode - record a znode obsoleted since last commit start. + * @c: UBIFS file-system description object + * @znode: znode of obsoleted index node + * + * Returns %0 on success, and a negative error code on failure. + */ +static int ins_clr_old_idx_znode(struct ubifs_info *c, + struct ubifs_znode *znode) +{ + int err; + + if (znode->parent) { + struct ubifs_zbranch *zbr; + + zbr = &znode->parent->zbranch[znode->iip]; + if (zbr->len) { + err = insert_old_idx(c, zbr->lnum, zbr->offs); + if (err) + return err; + zbr->lnum = 0; + zbr->offs = 0; + zbr->len = 0; + } + } else + if (c->zroot.len) { + err = insert_old_idx(c, c->zroot.lnum, c->zroot.offs); + if (err) + return err; + c->zroot.lnum = 0; + c->zroot.offs = 0; + c->zroot.len = 0; + } + return 0; +} + +/** + * destroy_old_idx - destroy the old_idx RB-tree. + * @c: UBIFS file-system description object + * + * During start commit, the old_idx RB-tree is used to avoid overwriting index + * nodes that were in the index last commit but have since been deleted. This + * is necessary for recovery i.e. the old index must be kept intact until the + * new index is successfully written. The old-idx RB-tree is used for the + * in-the-gaps method of writing index nodes and is destroyed every commit. + */ +void destroy_old_idx(struct ubifs_info *c) +{ + struct rb_node *this = c->old_idx.rb_node; + struct ubifs_old_idx *old_idx; + + while (this) { + if (this->rb_left) { + this = this->rb_left; + continue; + } else if (this->rb_right) { + this = this->rb_right; + continue; + } + old_idx = rb_entry(this, struct ubifs_old_idx, rb); + this = rb_parent(this); + if (this) { + if (this->rb_left == &old_idx->rb) + this->rb_left = NULL; + else + this->rb_right = NULL; + } + kfree(old_idx); + } + c->old_idx = RB_ROOT; +} + +/** + * copy_znode - copy a dirty znode. + * @c: UBIFS file-system description object + * @znode: znode to copy + * + * A dirty znode being committed may not be changed, so it is copied. + */ +static struct ubifs_znode *copy_znode(struct ubifs_info *c, + struct ubifs_znode *znode) +{ + struct ubifs_znode *zn; + + zn = kmalloc(c->max_znode_sz, GFP_NOFS); + if (unlikely(!zn)) + return ERR_PTR(-ENOMEM); + + memcpy(zn, znode, c->max_znode_sz); + zn->cnext = NULL; + __set_bit(DIRTY_ZNODE, &zn->flags); + __clear_bit(COW_ZNODE, &zn->flags); + + ubifs_assert(!test_bit(OBSOLETE_ZNODE, &znode->flags)); + __set_bit(OBSOLETE_ZNODE, &znode->flags); + + if (znode->level != 0) { + int i; + const int n = zn->child_cnt; + + /* The children now have new parent */ + for (i = 0; i < n; i++) { + struct ubifs_zbranch *zbr = &zn->zbranch[i]; + + if (zbr->znode) + zbr->znode->parent = zn; + } + } + + atomic_long_inc(&c->dirty_zn_cnt); + return zn; +} + +/** + * add_idx_dirt - add dirt due to a dirty znode. + * @c: UBIFS file-system description object + * @lnum: LEB number of index node + * @dirt: size of index node + * + * This function updates lprops dirty space and the new size of the index. + */ +static int add_idx_dirt(struct ubifs_info *c, int lnum, int dirt) +{ + c->calc_idx_sz -= ALIGN(dirt, 8); + return ubifs_add_dirt(c, lnum, dirt); +} + +/** + * dirty_cow_znode - ensure a znode is not being committed. + * @c: UBIFS file-system description object + * @zbr: branch of znode to check + * + * Returns dirtied znode on success or negative error code on failure. + */ +static struct ubifs_znode *dirty_cow_znode(struct ubifs_info *c, + struct ubifs_zbranch *zbr) +{ + struct ubifs_znode *znode = zbr->znode; + struct ubifs_znode *zn; + int err; + + if (!test_bit(COW_ZNODE, &znode->flags)) { + /* znode is not being committed */ + if (!test_and_set_bit(DIRTY_ZNODE, &znode->flags)) { + atomic_long_inc(&c->dirty_zn_cnt); + atomic_long_dec(&c->clean_zn_cnt); + atomic_long_dec(&ubifs_clean_zn_cnt); + err = add_idx_dirt(c, zbr->lnum, zbr->len); + if (unlikely(err)) + return ERR_PTR(err); + } + return znode; + } + + zn = copy_znode(c, znode); + if (IS_ERR(zn)) + return zn; + + if (zbr->len) { + err = insert_old_idx(c, zbr->lnum, zbr->offs); + if (unlikely(err)) + return ERR_PTR(err); + err = add_idx_dirt(c, zbr->lnum, zbr->len); + } else + err = 0; + + zbr->znode = zn; + zbr->lnum = 0; + zbr->offs = 0; + zbr->len = 0; + + if (unlikely(err)) + return ERR_PTR(err); + return zn; +} + +/** + * lnc_add - add a leaf node to the leaf node cache. + * @c: UBIFS file-system description object + * @zbr: zbranch of leaf node + * @node: leaf node + * + * Leaf nodes are non-index nodes directory entry nodes or data nodes. The + * purpose of the leaf node cache is to save re-reading the same leaf node over + * and over again. Most things are cached by VFS, however the file system must + * cache directory entries for readdir and for resolving hash collisions. The + * present implementation of the leaf node cache is extremely simple, and + * allows for error returns that are not used but that may be needed if a more + * complex implementation is created. + * + * Note, this function does not add the @node object to LNC directly, but + * allocates a copy of the object and adds the copy to LNC. The reason for this + * is that @node has been allocated outside of the TNC subsystem and will be + * used with @c->tnc_mutex unlock upon return from the TNC subsystem. But LNC + * may be changed at any time, e.g. freed by the shrinker. + */ +static int lnc_add(struct ubifs_info *c, struct ubifs_zbranch *zbr, + const void *node) +{ + int err; + void *lnc_node; + const struct ubifs_dent_node *dent = node; + + ubifs_assert(!zbr->leaf); + ubifs_assert(zbr->len != 0); + ubifs_assert(is_hash_key(c, &zbr->key)); + + err = ubifs_validate_entry(c, dent); + if (err) { + dbg_dump_stack(); + dbg_dump_node(c, dent); + return err; + } + + lnc_node = kmalloc(zbr->len, GFP_NOFS); + if (!lnc_node) + /* We don't have to have the cache, so no error */ + return 0; + + memcpy(lnc_node, node, zbr->len); + zbr->leaf = lnc_node; + return 0; +} + + /** + * lnc_add_directly - add a leaf node to the leaf-node-cache. + * @c: UBIFS file-system description object + * @zbr: zbranch of leaf node + * @node: leaf node + * + * This function is similar to 'lnc_add()', but it does not create a copy of + * @node but inserts @node to TNC directly. + */ +static int lnc_add_directly(struct ubifs_info *c, struct ubifs_zbranch *zbr, + void *node) +{ + int err; + + ubifs_assert(!zbr->leaf); + ubifs_assert(zbr->len != 0); + + err = ubifs_validate_entry(c, node); + if (err) { + dbg_dump_stack(); + dbg_dump_node(c, node); + return err; + } + + zbr->leaf = node; + return 0; +} + +/** + * lnc_free - remove a leaf node from the leaf node cache. + * @zbr: zbranch of leaf node + * @node: leaf node + */ +static void lnc_free(struct ubifs_zbranch *zbr) +{ + if (!zbr->leaf) + return; + kfree(zbr->leaf); + zbr->leaf = NULL; +} + +/** + * tnc_read_node_nm - read a "hashed" leaf node. + * @c: UBIFS file-system description object + * @zbr: key and position of the node + * @node: node is returned here + * + * This function reads a "hashed" node defined by @zbr from the leaf node cache + * (in it is there) or from the hash media, in which case the node is also + * added to LNC. Returns zero in case of success or a negative negative error + * code in case of failure. + */ +static int tnc_read_node_nm(struct ubifs_info *c, struct ubifs_zbranch *zbr, + void *node) +{ + int err; + + ubifs_assert(is_hash_key(c, &zbr->key)); + + if (zbr->leaf) { + /* Read from the leaf node cache */ + ubifs_assert(zbr->len != 0); + memcpy(node, zbr->leaf, zbr->len); + return 0; + } + + err = ubifs_tnc_read_node(c, zbr, node); + if (err) + return err; + + /* Add the node to the leaf node cache */ + err = lnc_add(c, zbr, node); + return err; +} + +/** + * try_read_node - read a node if it is a node. + * @c: UBIFS file-system description object + * @buf: buffer to read to + * @type: node type + * @len: node length (not aligned) + * @lnum: LEB number of node to read + * @offs: offset of node to read + * + * This function tries to read a node of known type and length, checks it and + * stores it in @buf. This function returns %1 if a node is present and %0 if + * a node is not present. A negative error code is returned for I/O errors. + * This function performs that same function as ubifs_read_node except that + * it does not require that there is actually a node present and instead + * the return code indicates if a node was read. + * + * Note, this function does not check CRC of data nodes if @c->no_chk_data_crc + * is true (it is controlled by corresponding mount option). However, if + * @c->always_chk_crc is true, @c->no_chk_data_crc is ignored and CRC is always + * checked. + */ +static int try_read_node(const struct ubifs_info *c, void *buf, int type, + int len, int lnum, int offs) +{ + int err, node_len; + struct ubifs_ch *ch = buf; + uint32_t crc, node_crc; + + dbg_io("LEB %d:%d, %s, length %d", lnum, offs, dbg_ntype(type), len); + + err = ubi_read(c->ubi, lnum, buf, offs, len); + if (err) { + ubifs_err("cannot read node type %d from LEB %d:%d, error %d", + type, lnum, offs, err); + return err; + } + + if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC) + return 0; + + if (ch->node_type != type) + return 0; + + node_len = le32_to_cpu(ch->len); + if (node_len != len) + return 0; + + if (type == UBIFS_DATA_NODE && !c->always_chk_crc && c->no_chk_data_crc) + return 1; + + crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8); + node_crc = le32_to_cpu(ch->crc); + if (crc != node_crc) + return 0; + + return 1; +} + +/** + * fallible_read_node - try to read a leaf node. + * @c: UBIFS file-system description object + * @key: key of node to read + * @zbr: position of node + * @node: node returned + * + * This function tries to read a node and returns %1 if the node is read, %0 + * if the node is not present, and a negative error code in the case of error. + */ +static int fallible_read_node(struct ubifs_info *c, const union ubifs_key *key, + struct ubifs_zbranch *zbr, void *node) +{ + int ret; + + dbg_tnc("LEB %d:%d, key %s", zbr->lnum, zbr->offs, DBGKEY(key)); + + ret = try_read_node(c, node, key_type(c, key), zbr->len, zbr->lnum, + zbr->offs); + if (ret == 1) { + union ubifs_key node_key; + struct ubifs_dent_node *dent = node; + + /* All nodes have key in the same place */ + key_read(c, &dent->key, &node_key); + if (keys_cmp(c, key, &node_key) != 0) + ret = 0; + } + if (ret == 0 && c->replaying) + dbg_mnt("dangling branch LEB %d:%d len %d, key %s", + zbr->lnum, zbr->offs, zbr->len, DBGKEY(key)); + return ret; +} + +/** + * matches_name - determine if a direntry or xattr entry matches a given name. + * @c: UBIFS file-system description object + * @zbr: zbranch of dent + * @nm: name to match + * + * This function checks if xentry/direntry referred by zbranch @zbr matches name + * @nm. Returns %NAME_MATCHES if it does, %NAME_LESS if the name referred by + * @zbr is less than @nm, and %NAME_GREATER if it is greater than @nm. In case + * of failure, a negative error code is returned. + */ +static int matches_name(struct ubifs_info *c, struct ubifs_zbranch *zbr, + const struct qstr *nm) +{ + struct ubifs_dent_node *dent; + int nlen, err; + + /* If possible, match against the dent in the leaf node cache */ + if (!zbr->leaf) { + dent = kmalloc(zbr->len, GFP_NOFS); + if (!dent) + return -ENOMEM; + + err = ubifs_tnc_read_node(c, zbr, dent); + if (err) + goto out_free; + + /* Add the node to the leaf node cache */ + err = lnc_add_directly(c, zbr, dent); + if (err) + goto out_free; + } else + dent = zbr->leaf; + + nlen = le16_to_cpu(dent->nlen); + err = memcmp(dent->name, nm->name, min_t(int, nlen, nm->len)); + if (err == 0) { + if (nlen == nm->len) + return NAME_MATCHES; + else if (nlen < nm->len) + return NAME_LESS; + else + return NAME_GREATER; + } else if (err < 0) + return NAME_LESS; + else + return NAME_GREATER; + +out_free: + kfree(dent); + return err; +} + +/** + * get_znode - get a TNC znode that may not be loaded yet. + * @c: UBIFS file-system description object + * @znode: parent znode + * @n: znode branch slot number + * + * This function returns the znode or a negative error code. + */ +static struct ubifs_znode *get_znode(struct ubifs_info *c, + struct ubifs_znode *znode, int n) +{ + struct ubifs_zbranch *zbr; + + zbr = &znode->zbranch[n]; + if (zbr->znode) + znode = zbr->znode; + else + znode = ubifs_load_znode(c, zbr, znode, n); + return znode; +} + +/** + * tnc_next - find next TNC entry. + * @c: UBIFS file-system description object + * @zn: znode is passed and returned here + * @n: znode branch slot number is passed and returned here + * + * This function returns %0 if the next TNC entry is found, %-ENOENT if there is + * no next entry, or a negative error code otherwise. + */ +static int tnc_next(struct ubifs_info *c, struct ubifs_znode **zn, int *n) +{ + struct ubifs_znode *znode = *zn; + int nn = *n; + + nn += 1; + if (nn < znode->child_cnt) { + *n = nn; + return 0; + } + while (1) { + struct ubifs_znode *zp; + + zp = znode->parent; + if (!zp) + return -ENOENT; + nn = znode->iip + 1; + znode = zp; + if (nn < znode->child_cnt) { + znode = get_znode(c, znode, nn); + if (IS_ERR(znode)) + return PTR_ERR(znode); + while (znode->level != 0) { + znode = get_znode(c, znode, 0); + if (IS_ERR(znode)) + return PTR_ERR(znode); + } + nn = 0; + break; + } + } + *zn = znode; + *n = nn; + return 0; +} + +/** + * tnc_prev - find previous TNC entry. + * @c: UBIFS file-system description object + * @zn: znode is returned here + * @n: znode branch slot number is passed and returned here + * + * This function returns %0 if the previous TNC entry is found, %-ENOENT if + * there is no next entry, or a negative error code otherwise. + */ +static int tnc_prev(struct ubifs_info *c, struct ubifs_znode **zn, int *n) +{ + struct ubifs_znode *znode = *zn; + int nn = *n; + + if (nn > 0) { + *n = nn - 1; + return 0; + } + while (1) { + struct ubifs_znode *zp; + + zp = znode->parent; + if (!zp) + return -ENOENT; + nn = znode->iip - 1; + znode = zp; + if (nn >= 0) { + znode = get_znode(c, znode, nn); + if (IS_ERR(znode)) + return PTR_ERR(znode); + while (znode->level != 0) { + nn = znode->child_cnt - 1; + znode = get_znode(c, znode, nn); + if (IS_ERR(znode)) + return PTR_ERR(znode); + } + nn = znode->child_cnt - 1; + break; + } + } + *zn = znode; + *n = nn; + return 0; +} + +/** + * resolve_collision - resolve a collision. + * @c: UBIFS file-system description object + * @key: key of a directory or extended attribute entry + * @zn: znode is returned here + * @n: zbranch number is passed and returned here + * @nm: name of the entry + * + * This function is called for "hashed" keys to make sure that the found key + * really corresponds to the looked up node (directory or extended attribute + * entry). It returns %1 and sets @zn and @n if the collision is resolved. + * %0 is returned if @nm is not found and @zn and @n are set to the previous + * entry, i.e. to the entry after which @nm could follow if it were in TNC. + * This means that @n may be set to %-1 if the leftmost key in @zn is the + * previous one. A negative error code is returned on failures. + */ +static int resolve_collision(struct ubifs_info *c, const union ubifs_key *key, + struct ubifs_znode **zn, int *n, + const struct qstr *nm) +{ + int err; + + err = matches_name(c, &(*zn)->zbranch[*n], nm); + if (unlikely(err < 0)) + return err; + if (err == NAME_MATCHES) + return 1; + + if (err == NAME_GREATER) { + /* Look left */ + while (1) { + err = tnc_prev(c, zn, n); + if (err == -ENOENT) { + ubifs_assert(*n == 0); + *n = -1; + return 0; + } + if (err < 0) + return err; + if (keys_cmp(c, &(*zn)->zbranch[*n].key, key)) { + /* + * We have found the branch after which we would + * like to insert, but inserting in this znode + * may still be wrong. Consider the following 3 + * znodes, in the case where we are resolving a + * collision with Key2. + * + * znode zp + * ---------------------- + * level 1 | Key0 | Key1 | + * ----------------------- + * | | + * znode za | | znode zb + * ------------ ------------ + * level 0 | Key0 | | Key2 | + * ------------ ------------ + * + * The lookup finds Key2 in znode zb. Lets say + * there is no match and the name is greater so + * we look left. When we find Key0, we end up + * here. If we return now, we will insert into + * znode za at slot n = 1. But that is invalid + * according to the parent's keys. Key2 must + * be inserted into znode zb. + * + * Note, this problem is not relevant for the + * case when we go right, because + * 'tnc_insert()' would correct the parent key. + */ + if (*n == (*zn)->child_cnt - 1) { + err = tnc_next(c, zn, n); + if (err) { + /* Should be impossible */ + ubifs_assert(0); + if (err == -ENOENT) + err = -EINVAL; + return err; + } + ubifs_assert(*n == 0); + *n = -1; + } + return 0; + } + err = matches_name(c, &(*zn)->zbranch[*n], nm); + if (err < 0) + return err; + if (err == NAME_LESS) + return 0; + if (err == NAME_MATCHES) + return 1; + ubifs_assert(err == NAME_GREATER); + } + } else { + int nn = *n; + struct ubifs_znode *znode = *zn; + + /* Look right */ + while (1) { + err = tnc_next(c, &znode, &nn); + if (err == -ENOENT) + return 0; + if (err < 0) + return err; + if (keys_cmp(c, &znode->zbranch[nn].key, key)) + return 0; + err = matches_name(c, &znode->zbranch[nn], nm); + if (err < 0) + return err; + if (err == NAME_GREATER) + return 0; + *zn = znode; + *n = nn; + if (err == NAME_MATCHES) + return 1; + ubifs_assert(err == NAME_LESS); + } + } +} + +/** + * fallible_matches_name - determine if a dent matches a given name. + * @c: UBIFS file-system description object + * @zbr: zbranch of dent + * @nm: name to match + * + * This is a "fallible" version of 'matches_name()' function which does not + * panic if the direntry/xentry referred by @zbr does not exist on the media. + * + * This function checks if xentry/direntry referred by zbranch @zbr matches name + * @nm. Returns %NAME_MATCHES it does, %NAME_LESS if the name referred by @zbr + * is less than @nm, %NAME_GREATER if it is greater than @nm, and @NOT_ON_MEDIA + * if xentry/direntry referred by @zbr does not exist on the media. A negative + * error code is returned in case of failure. + */ +static int fallible_matches_name(struct ubifs_info *c, + struct ubifs_zbranch *zbr, + const struct qstr *nm) +{ + struct ubifs_dent_node *dent; + int nlen, err; + + /* If possible, match against the dent in the leaf node cache */ + if (!zbr->leaf) { + dent = kmalloc(zbr->len, GFP_NOFS); + if (!dent) + return -ENOMEM; + + err = fallible_read_node(c, &zbr->key, zbr, dent); + if (err < 0) + goto out_free; + if (err == 0) { + /* The node was not present */ + err = NOT_ON_MEDIA; + goto out_free; + } + ubifs_assert(err == 1); + + err = lnc_add_directly(c, zbr, dent); + if (err) + goto out_free; + } else + dent = zbr->leaf; + + nlen = le16_to_cpu(dent->nlen); + err = memcmp(dent->name, nm->name, min_t(int, nlen, nm->len)); + if (err == 0) { + if (nlen == nm->len) + return NAME_MATCHES; + else if (nlen < nm->len) + return NAME_LESS; + else + return NAME_GREATER; + } else if (err < 0) + return NAME_LESS; + else + return NAME_GREATER; + +out_free: + kfree(dent); + return err; +} + +/** + * fallible_resolve_collision - resolve a collision even if nodes are missing. + * @c: UBIFS file-system description object + * @key: key + * @zn: znode is returned here + * @n: branch number is passed and returned here + * @nm: name of directory entry + * @adding: indicates caller is adding a key to the TNC + * + * This is a "fallible" version of the 'resolve_collision()' function which + * does not panic if one of the nodes referred to by TNC does not exist on the + * media. This may happen when replaying the journal if a deleted node was + * Garbage-collected and the commit was not done. A branch that refers to a node + * that is not present is called a dangling branch. The following are the return + * codes for this function: + * o if @nm was found, %1 is returned and @zn and @n are set to the found + * branch; + * o if we are @adding and @nm was not found, %0 is returned; + * o if we are not @adding and @nm was not found, but a dangling branch was + * found, then %1 is returned and @zn and @n are set to the dangling branch; + * o a negative error code is returned in case of failure. + */ +static int fallible_resolve_collision(struct ubifs_info *c, + const union ubifs_key *key, + struct ubifs_znode **zn, int *n, + const struct qstr *nm, int adding) +{ + struct ubifs_znode *o_znode = NULL, *znode = *zn; + int uninitialized_var(o_n), err, cmp, unsure = 0, nn = *n; + + cmp = fallible_matches_name(c, &znode->zbranch[nn], nm); + if (unlikely(cmp < 0)) + return cmp; + if (cmp == NAME_MATCHES) + return 1; + if (cmp == NOT_ON_MEDIA) { + o_znode = znode; + o_n = nn; + /* + * We are unlucky and hit a dangling branch straight away. + * Now we do not really know where to go to find the needed + * branch - to the left or to the right. Well, let's try left. + */ + unsure = 1; + } else if (!adding) + unsure = 1; /* Remove a dangling branch wherever it is */ + + if (cmp == NAME_GREATER || unsure) { + /* Look left */ + while (1) { + err = tnc_prev(c, zn, n); + if (err == -ENOENT) { + ubifs_assert(*n == 0); + *n = -1; + break; + } + if (err < 0) + return err; + if (keys_cmp(c, &(*zn)->zbranch[*n].key, key)) { + /* See comments in 'resolve_collision()' */ + if (*n == (*zn)->child_cnt - 1) { + err = tnc_next(c, zn, n); + if (err) { + /* Should be impossible */ + ubifs_assert(0); + if (err == -ENOENT) + err = -EINVAL; + return err; + } + ubifs_assert(*n == 0); + *n = -1; + } + break; + } + err = fallible_matches_name(c, &(*zn)->zbranch[*n], nm); + if (err < 0) + return err; + if (err == NAME_MATCHES) + return 1; + if (err == NOT_ON_MEDIA) { + o_znode = *zn; + o_n = *n; + continue; + } + if (!adding) + continue; + if (err == NAME_LESS) + break; + else + unsure = 0; + } + } + + if (cmp == NAME_LESS || unsure) { + /* Look right */ + *zn = znode; + *n = nn; + while (1) { + err = tnc_next(c, &znode, &nn); + if (err == -ENOENT) + break; + if (err < 0) + return err; + if (keys_cmp(c, &znode->zbranch[nn].key, key)) + break; + err = fallible_matches_name(c, &znode->zbranch[nn], nm); + if (err < 0) + return err; + if (err == NAME_GREATER) + break; + *zn = znode; + *n = nn; + if (err == NAME_MATCHES) + return 1; + if (err == NOT_ON_MEDIA) { + o_znode = znode; + o_n = nn; + } + } + } + + /* Never match a dangling branch when adding */ + if (adding || !o_znode) + return 0; + + dbg_mnt("dangling match LEB %d:%d len %d %s", + o_znode->zbranch[o_n].lnum, o_znode->zbranch[o_n].offs, + o_znode->zbranch[o_n].len, DBGKEY(key)); + *zn = o_znode; + *n = o_n; + return 1; +} + +/** + * matches_position - determine if a zbranch matches a given position. + * @zbr: zbranch of dent + * @lnum: LEB number of dent to match + * @offs: offset of dent to match + * + * This function returns %1 if @lnum:@offs matches, and %0 otherwise. + */ +static int matches_position(struct ubifs_zbranch *zbr, int lnum, int offs) +{ + if (zbr->lnum == lnum && zbr->offs == offs) + return 1; + else + return 0; +} + +/** + * resolve_collision_directly - resolve a collision directly. + * @c: UBIFS file-system description object + * @key: key of directory entry + * @zn: znode is passed and returned here + * @n: zbranch number is passed and returned here + * @lnum: LEB number of dent node to match + * @offs: offset of dent node to match + * + * This function is used for "hashed" keys to make sure the found directory or + * extended attribute entry node is what was looked for. It is used when the + * flash address of the right node is known (@lnum:@offs) which makes it much + * easier to resolve collisions (no need to read entries and match full + * names). This function returns %1 and sets @zn and @n if the collision is + * resolved, %0 if @lnum:@offs is not found and @zn and @n are set to the + * previous directory entry. Otherwise a negative error code is returned. + */ +static int resolve_collision_directly(struct ubifs_info *c, + const union ubifs_key *key, + struct ubifs_znode **zn, int *n, + int lnum, int offs) +{ + struct ubifs_znode *znode; + int nn, err; + + znode = *zn; + nn = *n; + if (matches_position(&znode->zbranch[nn], lnum, offs)) + return 1; + + /* Look left */ + while (1) { + err = tnc_prev(c, &znode, &nn); + if (err == -ENOENT) + break; + if (err < 0) + return err; + if (keys_cmp(c, &znode->zbranch[nn].key, key)) + break; + if (matches_position(&znode->zbranch[nn], lnum, offs)) { + *zn = znode; + *n = nn; + return 1; + } + } + + /* Look right */ + znode = *zn; + nn = *n; + while (1) { + err = tnc_next(c, &znode, &nn); + if (err == -ENOENT) + return 0; + if (err < 0) + return err; + if (keys_cmp(c, &znode->zbranch[nn].key, key)) + return 0; + *zn = znode; + *n = nn; + if (matches_position(&znode->zbranch[nn], lnum, offs)) + return 1; + } +} + +/** + * dirty_cow_bottom_up - dirty a znode and its ancestors. + * @c: UBIFS file-system description object + * @znode: znode to dirty + * + * If we do not have a unique key that resides in a znode, then we cannot + * dirty that znode from the top down (i.e. by using lookup_level0_dirty) + * This function records the path back to the last dirty ancestor, and then + * dirties the znodes on that path. + */ +static struct ubifs_znode *dirty_cow_bottom_up(struct ubifs_info *c, + struct ubifs_znode *znode) +{ + struct ubifs_znode *zp; + int *path = c->bottom_up_buf, p = 0; + + ubifs_assert(c->zroot.znode); + ubifs_assert(znode); + if (c->zroot.znode->level > BOTTOM_UP_HEIGHT) { + kfree(c->bottom_up_buf); + c->bottom_up_buf = kmalloc(c->zroot.znode->level * sizeof(int), + GFP_NOFS); + if (!c->bottom_up_buf) + return ERR_PTR(-ENOMEM); + path = c->bottom_up_buf; + } + if (c->zroot.znode->level) { + /* Go up until parent is dirty */ + while (1) { + int n; + + zp = znode->parent; + if (!zp) + break; + n = znode->iip; + ubifs_assert(p < c->zroot.znode->level); + path[p++] = n; + if (!zp->cnext && ubifs_zn_dirty(znode)) + break; + znode = zp; + } + } + + /* Come back down, dirtying as we go */ + while (1) { + struct ubifs_zbranch *zbr; + + zp = znode->parent; + if (zp) { + ubifs_assert(path[p - 1] >= 0); + ubifs_assert(path[p - 1] < zp->child_cnt); + zbr = &zp->zbranch[path[--p]]; + znode = dirty_cow_znode(c, zbr); + } else { + ubifs_assert(znode == c->zroot.znode); + znode = dirty_cow_znode(c, &c->zroot); + } + if (IS_ERR(znode) || !p) + break; + ubifs_assert(path[p - 1] >= 0); + ubifs_assert(path[p - 1] < znode->child_cnt); + znode = znode->zbranch[path[p - 1]].znode; + } + + return znode; +} + +/** + * ubifs_lookup_level0 - search for zero-level znode. + * @c: UBIFS file-system description object + * @key: key to lookup + * @zn: znode is returned here + * @n: znode branch slot number is returned here + * + * This function looks up the TNC tree and search for zero-level znode which + * refers key @key. The found zero-level znode is returned in @zn. There are 3 + * cases: + * o exact match, i.e. the found zero-level znode contains key @key, then %1 + * is returned and slot number of the matched branch is stored in @n; + * o not exact match, which means that zero-level znode does not contain + * @key, then %0 is returned and slot number of the closed branch is stored + * in @n; + * o @key is so small that it is even less than the lowest key of the + * leftmost zero-level node, then %0 is returned and %0 is stored in @n. + * + * Note, when the TNC tree is traversed, some znodes may be absent, then this + * function reads corresponding indexing nodes and inserts them to TNC. In + * case of failure, a negative error code is returned. + */ +int ubifs_lookup_level0(struct ubifs_info *c, const union ubifs_key *key, + struct ubifs_znode **zn, int *n) +{ + int err, exact; + struct ubifs_znode *znode; + unsigned long time = get_seconds(); + + dbg_tnc("search key %s", DBGKEY(key)); + + znode = c->zroot.znode; + if (unlikely(!znode)) { + znode = ubifs_load_znode(c, &c->zroot, NULL, 0); + if (IS_ERR(znode)) + return PTR_ERR(znode); + } + + znode->time = time; + + while (1) { + struct ubifs_zbranch *zbr; + + exact = ubifs_search_zbranch(c, znode, key, n); + + if (znode->level == 0) + break; + + if (*n < 0) + *n = 0; + zbr = &znode->zbranch[*n]; + + if (zbr->znode) { + znode->time = time; + znode = zbr->znode; + continue; + } + + /* znode is not in TNC cache, load it from the media */ + znode = ubifs_load_znode(c, zbr, znode, *n); + if (IS_ERR(znode)) + return PTR_ERR(znode); + } + + *zn = znode; + if (exact || !is_hash_key(c, key) || *n != -1) { + dbg_tnc("found %d, lvl %d, n %d", exact, znode->level, *n); + return exact; + } + + /* + * Here is a tricky place. We have not found the key and this is a + * "hashed" key, which may collide. The rest of the code deals with + * situations like this: + * + * | 3 | 5 | + * / \ + * | 3 | 5 | | 6 | 7 | (x) + * + * Or more a complex example: + * + * | 1 | 5 | + * / \ + * | 1 | 3 | | 5 | 8 | + * \ / + * | 5 | 5 | | 6 | 7 | (x) + * + * In the examples, if we are looking for key "5", we may reach nodes + * marked with "(x)". In this case what we have do is to look at the + * left and see if there is "5" key there. If there is, we have to + * return it. + * + * Note, this whole situation is possible because we allow to have + * elements which are equivalent to the next key in the parent in the + * children of current znode. For example, this happens if we split a + * znode like this: | 3 | 5 | 5 | 6 | 7 |, which results in something + * like this: + * | 3 | 5 | + * / \ + * | 3 | 5 | | 5 | 6 | 7 | + * ^ + * And this becomes what is at the first "picture" after key "5" marked + * with "^" is removed. What could be done is we could prohibit + * splitting in the middle of the colliding sequence. Also, when + * removing the leftmost key, we would have to correct the key of the + * parent node, which would introduce additional complications. Namely, + * if we changed the the leftmost key of the parent znode, the garbage + * collector would be unable to find it (GC is doing this when GC'ing + * indexing LEBs). Although we already have an additional RB-tree where + * we save such changed znodes (see 'ins_clr_old_idx_znode()') until + * after the commit. But anyway, this does not look easy to implement + * so we did not try this. + */ + err = tnc_prev(c, &znode, n); + if (err == -ENOENT) { + dbg_tnc("found 0, lvl %d, n -1", znode->level); + *n = -1; + return 0; + } + if (unlikely(err < 0)) + return err; + if (keys_cmp(c, key, &znode->zbranch[*n].key)) { + dbg_tnc("found 0, lvl %d, n -1", znode->level); + *n = -1; + return 0; + } + + dbg_tnc("found 1, lvl %d, n %d", znode->level, *n); + *zn = znode; + return 1; +} + +/** + * lookup_level0_dirty - search for zero-level znode dirtying. + * @c: UBIFS file-system description object + * @key: key to lookup + * @zn: znode is returned here + * @n: znode branch slot number is returned here + * + * This function looks up the TNC tree and search for zero-level znode which + * refers key @key. The found zero-level znode is returned in @zn. There are 3 + * cases: + * o exact match, i.e. the found zero-level znode contains key @key, then %1 + * is returned and slot number of the matched branch is stored in @n; + * o not exact match, which means that zero-level znode does not contain @key + * then %0 is returned and slot number of the closed branch is stored in + * @n; + * o @key is so small that it is even less than the lowest key of the + * leftmost zero-level node, then %0 is returned and %-1 is stored in @n. + * + * Additionally all znodes in the path from the root to the located zero-level + * znode are marked as dirty. + * + * Note, when the TNC tree is traversed, some znodes may be absent, then this + * function reads corresponding indexing nodes and inserts them to TNC. In + * case of failure, a negative error code is returned. + */ +static int lookup_level0_dirty(struct ubifs_info *c, const union ubifs_key *key, + struct ubifs_znode **zn, int *n) +{ + int err, exact; + struct ubifs_znode *znode; + unsigned long time = get_seconds(); + + dbg_tnc("search and dirty key %s", DBGKEY(key)); + + znode = c->zroot.znode; + if (unlikely(!znode)) { + znode = ubifs_load_znode(c, &c->zroot, NULL, 0); + if (IS_ERR(znode)) + return PTR_ERR(znode); + } + + znode = dirty_cow_znode(c, &c->zroot); + if (IS_ERR(znode)) + return PTR_ERR(znode); + + znode->time = time; + + while (1) { + struct ubifs_zbranch *zbr; + + exact = ubifs_search_zbranch(c, znode, key, n); + + if (znode->level == 0) + break; + + if (*n < 0) + *n = 0; + zbr = &znode->zbranch[*n]; + + if (zbr->znode) { + znode->time = time; + znode = dirty_cow_znode(c, zbr); + if (IS_ERR(znode)) + return PTR_ERR(znode); + continue; + } + + /* znode is not in TNC cache, load it from the media */ + znode = ubifs_load_znode(c, zbr, znode, *n); + if (IS_ERR(znode)) + return PTR_ERR(znode); + znode = dirty_cow_znode(c, zbr); + if (IS_ERR(znode)) + return PTR_ERR(znode); + } + + *zn = znode; + if (exact || !is_hash_key(c, key) || *n != -1) { + dbg_tnc("found %d, lvl %d, n %d", exact, znode->level, *n); + return exact; + } + + /* + * See huge comment at 'lookup_level0_dirty()' what is the rest of the + * code. + */ + err = tnc_prev(c, &znode, n); + if (err == -ENOENT) { + *n = -1; + dbg_tnc("found 0, lvl %d, n -1", znode->level); + return 0; + } + if (unlikely(err < 0)) + return err; + if (keys_cmp(c, key, &znode->zbranch[*n].key)) { + *n = -1; + dbg_tnc("found 0, lvl %d, n -1", znode->level); + return 0; + } + + if (znode->cnext || !ubifs_zn_dirty(znode)) { + znode = dirty_cow_bottom_up(c, znode); + if (IS_ERR(znode)) + return PTR_ERR(znode); + } + + dbg_tnc("found 1, lvl %d, n %d", znode->level, *n); + *zn = znode; + return 1; +} + +/** + * maybe_leb_gced - determine if a LEB may have been garbage collected. + * @c: UBIFS file-system description object + * @lnum: LEB number + * @gc_seq1: garbage collection sequence number + * + * This function determines if @lnum may have been garbage collected since + * sequence number @gc_seq1. If it may have been then %1 is returned, otherwise + * %0 is returned. + */ +static int maybe_leb_gced(struct ubifs_info *c, int lnum, int gc_seq1) +{ + /* + * No garbage collection in the read-only U-Boot implementation + */ + return 0; +} + +/** + * ubifs_tnc_locate - look up a file-system node and return it and its location. + * @c: UBIFS file-system description object + * @key: node key to lookup + * @node: the node is returned here + * @lnum: LEB number is returned here + * @offs: offset is returned here + * + * This function look up and reads node with key @key. The caller has to make + * sure the @node buffer is large enough to fit the node. Returns zero in case + * of success, %-ENOENT if the node was not found, and a negative error code in + * case of failure. The node location can be returned in @lnum and @offs. + */ +int ubifs_tnc_locate(struct ubifs_info *c, const union ubifs_key *key, + void *node, int *lnum, int *offs) +{ + int found, n, err, safely = 0, gc_seq1; + struct ubifs_znode *znode; + struct ubifs_zbranch zbr, *zt; + +again: + mutex_lock(&c->tnc_mutex); + found = ubifs_lookup_level0(c, key, &znode, &n); + if (!found) { + err = -ENOENT; + goto out; + } else if (found < 0) { + err = found; + goto out; + } + zt = &znode->zbranch[n]; + if (lnum) { + *lnum = zt->lnum; + *offs = zt->offs; + } + if (is_hash_key(c, key)) { + /* + * In this case the leaf node cache gets used, so we pass the + * address of the zbranch and keep the mutex locked + */ + err = tnc_read_node_nm(c, zt, node); + goto out; + } + if (safely) { + err = ubifs_tnc_read_node(c, zt, node); + goto out; + } + /* Drop the TNC mutex prematurely and race with garbage collection */ + zbr = znode->zbranch[n]; + gc_seq1 = c->gc_seq; + mutex_unlock(&c->tnc_mutex); + + err = fallible_read_node(c, key, &zbr, node); + if (err <= 0 || maybe_leb_gced(c, zbr.lnum, gc_seq1)) { + /* + * The node may have been GC'ed out from under us so try again + * while keeping the TNC mutex locked. + */ + safely = 1; + goto again; + } + return 0; + +out: + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * ubifs_tnc_get_bu_keys - lookup keys for bulk-read. + * @c: UBIFS file-system description object + * @bu: bulk-read parameters and results + * + * Lookup consecutive data node keys for the same inode that reside + * consecutively in the same LEB. This function returns zero in case of success + * and a negative error code in case of failure. + * + * Note, if the bulk-read buffer length (@bu->buf_len) is known, this function + * makes sure bulk-read nodes fit the buffer. Otherwise, this function prepares + * maximum possible amount of nodes for bulk-read. + */ +int ubifs_tnc_get_bu_keys(struct ubifs_info *c, struct bu_info *bu) +{ + int n, err = 0, lnum = -1, uninitialized_var(offs); + int uninitialized_var(len); + unsigned int block = key_block(c, &bu->key); + struct ubifs_znode *znode; + + bu->cnt = 0; + bu->blk_cnt = 0; + bu->eof = 0; + + mutex_lock(&c->tnc_mutex); + /* Find first key */ + err = ubifs_lookup_level0(c, &bu->key, &znode, &n); + if (err < 0) + goto out; + if (err) { + /* Key found */ + len = znode->zbranch[n].len; + /* The buffer must be big enough for at least 1 node */ + if (len > bu->buf_len) { + err = -EINVAL; + goto out; + } + /* Add this key */ + bu->zbranch[bu->cnt++] = znode->zbranch[n]; + bu->blk_cnt += 1; + lnum = znode->zbranch[n].lnum; + offs = ALIGN(znode->zbranch[n].offs + len, 8); + } + while (1) { + struct ubifs_zbranch *zbr; + union ubifs_key *key; + unsigned int next_block; + + /* Find next key */ + err = tnc_next(c, &znode, &n); + if (err) + goto out; + zbr = &znode->zbranch[n]; + key = &zbr->key; + /* See if there is another data key for this file */ + if (key_inum(c, key) != key_inum(c, &bu->key) || + key_type(c, key) != UBIFS_DATA_KEY) { + err = -ENOENT; + goto out; + } + if (lnum < 0) { + /* First key found */ + lnum = zbr->lnum; + offs = ALIGN(zbr->offs + zbr->len, 8); + len = zbr->len; + if (len > bu->buf_len) { + err = -EINVAL; + goto out; + } + } else { + /* + * The data nodes must be in consecutive positions in + * the same LEB. + */ + if (zbr->lnum != lnum || zbr->offs != offs) + goto out; + offs += ALIGN(zbr->len, 8); + len = ALIGN(len, 8) + zbr->len; + /* Must not exceed buffer length */ + if (len > bu->buf_len) + goto out; + } + /* Allow for holes */ + next_block = key_block(c, key); + bu->blk_cnt += (next_block - block - 1); + if (bu->blk_cnt >= UBIFS_MAX_BULK_READ) + goto out; + block = next_block; + /* Add this key */ + bu->zbranch[bu->cnt++] = *zbr; + bu->blk_cnt += 1; + /* See if we have room for more */ + if (bu->cnt >= UBIFS_MAX_BULK_READ) + goto out; + if (bu->blk_cnt >= UBIFS_MAX_BULK_READ) + goto out; + } +out: + if (err == -ENOENT) { + bu->eof = 1; + err = 0; + } + bu->gc_seq = c->gc_seq; + mutex_unlock(&c->tnc_mutex); + if (err) + return err; + /* + * An enormous hole could cause bulk-read to encompass too many + * page cache pages, so limit the number here. + */ + if (bu->blk_cnt > UBIFS_MAX_BULK_READ) + bu->blk_cnt = UBIFS_MAX_BULK_READ; + /* + * Ensure that bulk-read covers a whole number of page cache + * pages. + */ + if (UBIFS_BLOCKS_PER_PAGE == 1 || + !(bu->blk_cnt & (UBIFS_BLOCKS_PER_PAGE - 1))) + return 0; + if (bu->eof) { + /* At the end of file we can round up */ + bu->blk_cnt += UBIFS_BLOCKS_PER_PAGE - 1; + return 0; + } + /* Exclude data nodes that do not make up a whole page cache page */ + block = key_block(c, &bu->key) + bu->blk_cnt; + block &= ~(UBIFS_BLOCKS_PER_PAGE - 1); + while (bu->cnt) { + if (key_block(c, &bu->zbranch[bu->cnt - 1].key) < block) + break; + bu->cnt -= 1; + } + return 0; +} + +/** + * validate_data_node - validate data nodes for bulk-read. + * @c: UBIFS file-system description object + * @buf: buffer containing data node to validate + * @zbr: zbranch of data node to validate + * + * This functions returns %0 on success or a negative error code on failure. + */ +static int validate_data_node(struct ubifs_info *c, void *buf, + struct ubifs_zbranch *zbr) +{ + union ubifs_key key1; + struct ubifs_ch *ch = buf; + int err, len; + + if (ch->node_type != UBIFS_DATA_NODE) { + ubifs_err("bad node type (%d but expected %d)", + ch->node_type, UBIFS_DATA_NODE); + goto out_err; + } + + err = ubifs_check_node(c, buf, zbr->lnum, zbr->offs, 0, 0); + if (err) { + ubifs_err("expected node type %d", UBIFS_DATA_NODE); + goto out; + } + + len = le32_to_cpu(ch->len); + if (len != zbr->len) { + ubifs_err("bad node length %d, expected %d", len, zbr->len); + goto out_err; + } + + /* Make sure the key of the read node is correct */ + key_read(c, buf + UBIFS_KEY_OFFSET, &key1); + if (!keys_eq(c, &zbr->key, &key1)) { + ubifs_err("bad key in node at LEB %d:%d", + zbr->lnum, zbr->offs); + dbg_tnc("looked for key %s found node's key %s", + DBGKEY(&zbr->key), DBGKEY1(&key1)); + goto out_err; + } + + return 0; + +out_err: + err = -EINVAL; +out: + ubifs_err("bad node at LEB %d:%d", zbr->lnum, zbr->offs); + dbg_dump_node(c, buf); + dbg_dump_stack(); + return err; +} + +/** + * ubifs_tnc_bulk_read - read a number of data nodes in one go. + * @c: UBIFS file-system description object + * @bu: bulk-read parameters and results + * + * This functions reads and validates the data nodes that were identified by the + * 'ubifs_tnc_get_bu_keys()' function. This functions returns %0 on success, + * -EAGAIN to indicate a race with GC, or another negative error code on + * failure. + */ +int ubifs_tnc_bulk_read(struct ubifs_info *c, struct bu_info *bu) +{ + int lnum = bu->zbranch[0].lnum, offs = bu->zbranch[0].offs, len, err, i; + void *buf; + + len = bu->zbranch[bu->cnt - 1].offs; + len += bu->zbranch[bu->cnt - 1].len - offs; + if (len > bu->buf_len) { + ubifs_err("buffer too small %d vs %d", bu->buf_len, len); + return -EINVAL; + } + + /* Do the read */ + err = ubi_read(c->ubi, lnum, bu->buf, offs, len); + + /* Check for a race with GC */ + if (maybe_leb_gced(c, lnum, bu->gc_seq)) + return -EAGAIN; + + if (err && err != -EBADMSG) { + ubifs_err("failed to read from LEB %d:%d, error %d", + lnum, offs, err); + dbg_dump_stack(); + dbg_tnc("key %s", DBGKEY(&bu->key)); + return err; + } + + /* Validate the nodes read */ + buf = bu->buf; + for (i = 0; i < bu->cnt; i++) { + err = validate_data_node(c, buf, &bu->zbranch[i]); + if (err) + return err; + buf = buf + ALIGN(bu->zbranch[i].len, 8); + } + + return 0; +} + +/** + * do_lookup_nm- look up a "hashed" node. + * @c: UBIFS file-system description object + * @key: node key to lookup + * @node: the node is returned here + * @nm: node name + * + * This function look up and reads a node which contains name hash in the key. + * Since the hash may have collisions, there may be many nodes with the same + * key, so we have to sequentially look to all of them until the needed one is + * found. This function returns zero in case of success, %-ENOENT if the node + * was not found, and a negative error code in case of failure. + */ +static int do_lookup_nm(struct ubifs_info *c, const union ubifs_key *key, + void *node, const struct qstr *nm) +{ + int found, n, err; + struct ubifs_znode *znode; + + dbg_tnc("name '%.*s' key %s", nm->len, nm->name, DBGKEY(key)); + mutex_lock(&c->tnc_mutex); + found = ubifs_lookup_level0(c, key, &znode, &n); + if (!found) { + err = -ENOENT; + goto out_unlock; + } else if (found < 0) { + err = found; + goto out_unlock; + } + + ubifs_assert(n >= 0); + + err = resolve_collision(c, key, &znode, &n, nm); + dbg_tnc("rc returned %d, znode %p, n %d", err, znode, n); + if (unlikely(err < 0)) + goto out_unlock; + if (err == 0) { + err = -ENOENT; + goto out_unlock; + } + + err = tnc_read_node_nm(c, &znode->zbranch[n], node); + +out_unlock: + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * ubifs_tnc_lookup_nm - look up a "hashed" node. + * @c: UBIFS file-system description object + * @key: node key to lookup + * @node: the node is returned here + * @nm: node name + * + * This function look up and reads a node which contains name hash in the key. + * Since the hash may have collisions, there may be many nodes with the same + * key, so we have to sequentially look to all of them until the needed one is + * found. This function returns zero in case of success, %-ENOENT if the node + * was not found, and a negative error code in case of failure. + */ +int ubifs_tnc_lookup_nm(struct ubifs_info *c, const union ubifs_key *key, + void *node, const struct qstr *nm) +{ + int err, len; + const struct ubifs_dent_node *dent = node; + + /* + * We assume that in most of the cases there are no name collisions and + * 'ubifs_tnc_lookup()' returns us the right direntry. + */ + err = ubifs_tnc_lookup(c, key, node); + if (err) + return err; + + len = le16_to_cpu(dent->nlen); + if (nm->len == len && !memcmp(dent->name, nm->name, len)) + return 0; + + /* + * Unluckily, there are hash collisions and we have to iterate over + * them look at each direntry with colliding name hash sequentially. + */ + return do_lookup_nm(c, key, node, nm); +} + +/** + * correct_parent_keys - correct parent znodes' keys. + * @c: UBIFS file-system description object + * @znode: znode to correct parent znodes for + * + * This is a helper function for 'tnc_insert()'. When the key of the leftmost + * zbranch changes, keys of parent znodes have to be corrected. This helper + * function is called in such situations and corrects the keys if needed. + */ +static void correct_parent_keys(const struct ubifs_info *c, + struct ubifs_znode *znode) +{ + union ubifs_key *key, *key1; + + ubifs_assert(znode->parent); + ubifs_assert(znode->iip == 0); + + key = &znode->zbranch[0].key; + key1 = &znode->parent->zbranch[0].key; + + while (keys_cmp(c, key, key1) < 0) { + key_copy(c, key, key1); + znode = znode->parent; + znode->alt = 1; + if (!znode->parent || znode->iip) + break; + key1 = &znode->parent->zbranch[0].key; + } +} + +/** + * insert_zbranch - insert a zbranch into a znode. + * @znode: znode into which to insert + * @zbr: zbranch to insert + * @n: slot number to insert to + * + * This is a helper function for 'tnc_insert()'. UBIFS does not allow "gaps" in + * znode's array of zbranches and keeps zbranches consolidated, so when a new + * zbranch has to be inserted to the @znode->zbranches[]' array at the @n-th + * slot, zbranches starting from @n have to be moved right. + */ +static void insert_zbranch(struct ubifs_znode *znode, + const struct ubifs_zbranch *zbr, int n) +{ + int i; + + ubifs_assert(ubifs_zn_dirty(znode)); + + if (znode->level) { + for (i = znode->child_cnt; i > n; i--) { + znode->zbranch[i] = znode->zbranch[i - 1]; + if (znode->zbranch[i].znode) + znode->zbranch[i].znode->iip = i; + } + if (zbr->znode) + zbr->znode->iip = n; + } else + for (i = znode->child_cnt; i > n; i--) + znode->zbranch[i] = znode->zbranch[i - 1]; + + znode->zbranch[n] = *zbr; + znode->child_cnt += 1; + + /* + * After inserting at slot zero, the lower bound of the key range of + * this znode may have changed. If this znode is subsequently split + * then the upper bound of the key range may change, and furthermore + * it could change to be lower than the original lower bound. If that + * happens, then it will no longer be possible to find this znode in the + * TNC using the key from the index node on flash. That is bad because + * if it is not found, we will assume it is obsolete and may overwrite + * it. Then if there is an unclean unmount, we will start using the + * old index which will be broken. + * + * So we first mark znodes that have insertions at slot zero, and then + * if they are split we add their lnum/offs to the old_idx tree. + */ + if (n == 0) + znode->alt = 1; +} + +/** + * tnc_insert - insert a node into TNC. + * @c: UBIFS file-system description object + * @znode: znode to insert into + * @zbr: branch to insert + * @n: slot number to insert new zbranch to + * + * This function inserts a new node described by @zbr into znode @znode. If + * znode does not have a free slot for new zbranch, it is split. Parent znodes + * are splat as well if needed. Returns zero in case of success or a negative + * error code in case of failure. + */ +static int tnc_insert(struct ubifs_info *c, struct ubifs_znode *znode, + struct ubifs_zbranch *zbr, int n) +{ + struct ubifs_znode *zn, *zi, *zp; + int i, keep, move, appending = 0; + union ubifs_key *key = &zbr->key, *key1; + + ubifs_assert(n >= 0 && n <= c->fanout); + + /* Implement naive insert for now */ +again: + zp = znode->parent; + if (znode->child_cnt < c->fanout) { + ubifs_assert(n != c->fanout); + dbg_tnc("inserted at %d level %d, key %s", n, znode->level, + DBGKEY(key)); + + insert_zbranch(znode, zbr, n); + + /* Ensure parent's key is correct */ + if (n == 0 && zp && znode->iip == 0) + correct_parent_keys(c, znode); + + return 0; + } + + /* + * Unfortunately, @znode does not have more empty slots and we have to + * split it. + */ + dbg_tnc("splitting level %d, key %s", znode->level, DBGKEY(key)); + + if (znode->alt) + /* + * We can no longer be sure of finding this znode by key, so we + * record it in the old_idx tree. + */ + ins_clr_old_idx_znode(c, znode); + + zn = kzalloc(c->max_znode_sz, GFP_NOFS); + if (!zn) + return -ENOMEM; + zn->parent = zp; + zn->level = znode->level; + + /* Decide where to split */ + if (znode->level == 0 && key_type(c, key) == UBIFS_DATA_KEY) { + /* Try not to split consecutive data keys */ + if (n == c->fanout) { + key1 = &znode->zbranch[n - 1].key; + if (key_inum(c, key1) == key_inum(c, key) && + key_type(c, key1) == UBIFS_DATA_KEY) + appending = 1; + } else + goto check_split; + } else if (appending && n != c->fanout) { + /* Try not to split consecutive data keys */ + appending = 0; +check_split: + if (n >= (c->fanout + 1) / 2) { + key1 = &znode->zbranch[0].key; + if (key_inum(c, key1) == key_inum(c, key) && + key_type(c, key1) == UBIFS_DATA_KEY) { + key1 = &znode->zbranch[n].key; + if (key_inum(c, key1) != key_inum(c, key) || + key_type(c, key1) != UBIFS_DATA_KEY) { + keep = n; + move = c->fanout - keep; + zi = znode; + goto do_split; + } + } + } + } + + if (appending) { + keep = c->fanout; + move = 0; + } else { + keep = (c->fanout + 1) / 2; + move = c->fanout - keep; + } + + /* + * Although we don't at present, we could look at the neighbors and see + * if we can move some zbranches there. + */ + + if (n < keep) { + /* Insert into existing znode */ + zi = znode; + move += 1; + keep -= 1; + } else { + /* Insert into new znode */ + zi = zn; + n -= keep; + /* Re-parent */ + if (zn->level != 0) + zbr->znode->parent = zn; + } + +do_split: + + __set_bit(DIRTY_ZNODE, &zn->flags); + atomic_long_inc(&c->dirty_zn_cnt); + + zn->child_cnt = move; + znode->child_cnt = keep; + + dbg_tnc("moving %d, keeping %d", move, keep); + + /* Move zbranch */ + for (i = 0; i < move; i++) { + zn->zbranch[i] = znode->zbranch[keep + i]; + /* Re-parent */ + if (zn->level != 0) + if (zn->zbranch[i].znode) { + zn->zbranch[i].znode->parent = zn; + zn->zbranch[i].znode->iip = i; + } + } + + /* Insert new key and branch */ + dbg_tnc("inserting at %d level %d, key %s", n, zn->level, DBGKEY(key)); + + insert_zbranch(zi, zbr, n); + + /* Insert new znode (produced by spitting) into the parent */ + if (zp) { + if (n == 0 && zi == znode && znode->iip == 0) + correct_parent_keys(c, znode); + + /* Locate insertion point */ + n = znode->iip + 1; + + /* Tail recursion */ + zbr->key = zn->zbranch[0].key; + zbr->znode = zn; + zbr->lnum = 0; + zbr->offs = 0; + zbr->len = 0; + znode = zp; + + goto again; + } + + /* We have to split root znode */ + dbg_tnc("creating new zroot at level %d", znode->level + 1); + + zi = kzalloc(c->max_znode_sz, GFP_NOFS); + if (!zi) + return -ENOMEM; + + zi->child_cnt = 2; + zi->level = znode->level + 1; + + __set_bit(DIRTY_ZNODE, &zi->flags); + atomic_long_inc(&c->dirty_zn_cnt); + + zi->zbranch[0].key = znode->zbranch[0].key; + zi->zbranch[0].znode = znode; + zi->zbranch[0].lnum = c->zroot.lnum; + zi->zbranch[0].offs = c->zroot.offs; + zi->zbranch[0].len = c->zroot.len; + zi->zbranch[1].key = zn->zbranch[0].key; + zi->zbranch[1].znode = zn; + + c->zroot.lnum = 0; + c->zroot.offs = 0; + c->zroot.len = 0; + c->zroot.znode = zi; + + zn->parent = zi; + zn->iip = 1; + znode->parent = zi; + znode->iip = 0; + + return 0; +} + +/** + * ubifs_tnc_add - add a node to TNC. + * @c: UBIFS file-system description object + * @key: key to add + * @lnum: LEB number of node + * @offs: node offset + * @len: node length + * + * This function adds a node with key @key to TNC. The node may be new or it may + * obsolete some existing one. Returns %0 on success or negative error code on + * failure. + */ +int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum, + int offs, int len) +{ + int found, n, err = 0; + struct ubifs_znode *znode; + + mutex_lock(&c->tnc_mutex); + dbg_tnc("%d:%d, len %d, key %s", lnum, offs, len, DBGKEY(key)); + found = lookup_level0_dirty(c, key, &znode, &n); + if (!found) { + struct ubifs_zbranch zbr; + + zbr.znode = NULL; + zbr.lnum = lnum; + zbr.offs = offs; + zbr.len = len; + key_copy(c, key, &zbr.key); + err = tnc_insert(c, znode, &zbr, n + 1); + } else if (found == 1) { + struct ubifs_zbranch *zbr = &znode->zbranch[n]; + + lnc_free(zbr); + err = ubifs_add_dirt(c, zbr->lnum, zbr->len); + zbr->lnum = lnum; + zbr->offs = offs; + zbr->len = len; + } else + err = found; + if (!err) + err = dbg_check_tnc(c, 0); + mutex_unlock(&c->tnc_mutex); + + return err; +} + +/** + * ubifs_tnc_replace - replace a node in the TNC only if the old node is found. + * @c: UBIFS file-system description object + * @key: key to add + * @old_lnum: LEB number of old node + * @old_offs: old node offset + * @lnum: LEB number of node + * @offs: node offset + * @len: node length + * + * This function replaces a node with key @key in the TNC only if the old node + * is found. This function is called by garbage collection when node are moved. + * Returns %0 on success or negative error code on failure. + */ +int ubifs_tnc_replace(struct ubifs_info *c, const union ubifs_key *key, + int old_lnum, int old_offs, int lnum, int offs, int len) +{ + int found, n, err = 0; + struct ubifs_znode *znode; + + mutex_lock(&c->tnc_mutex); + dbg_tnc("old LEB %d:%d, new LEB %d:%d, len %d, key %s", old_lnum, + old_offs, lnum, offs, len, DBGKEY(key)); + found = lookup_level0_dirty(c, key, &znode, &n); + if (found < 0) { + err = found; + goto out_unlock; + } + + if (found == 1) { + struct ubifs_zbranch *zbr = &znode->zbranch[n]; + + found = 0; + if (zbr->lnum == old_lnum && zbr->offs == old_offs) { + lnc_free(zbr); + err = ubifs_add_dirt(c, zbr->lnum, zbr->len); + if (err) + goto out_unlock; + zbr->lnum = lnum; + zbr->offs = offs; + zbr->len = len; + found = 1; + } else if (is_hash_key(c, key)) { + found = resolve_collision_directly(c, key, &znode, &n, + old_lnum, old_offs); + dbg_tnc("rc returned %d, znode %p, n %d, LEB %d:%d", + found, znode, n, old_lnum, old_offs); + if (found < 0) { + err = found; + goto out_unlock; + } + + if (found) { + /* Ensure the znode is dirtied */ + if (znode->cnext || !ubifs_zn_dirty(znode)) { + znode = dirty_cow_bottom_up(c, znode); + if (IS_ERR(znode)) { + err = PTR_ERR(znode); + goto out_unlock; + } + } + zbr = &znode->zbranch[n]; + lnc_free(zbr); + err = ubifs_add_dirt(c, zbr->lnum, + zbr->len); + if (err) + goto out_unlock; + zbr->lnum = lnum; + zbr->offs = offs; + zbr->len = len; + } + } + } + + if (!found) + err = ubifs_add_dirt(c, lnum, len); + + if (!err) + err = dbg_check_tnc(c, 0); + +out_unlock: + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * ubifs_tnc_add_nm - add a "hashed" node to TNC. + * @c: UBIFS file-system description object + * @key: key to add + * @lnum: LEB number of node + * @offs: node offset + * @len: node length + * @nm: node name + * + * This is the same as 'ubifs_tnc_add()' but it should be used with keys which + * may have collisions, like directory entry keys. + */ +int ubifs_tnc_add_nm(struct ubifs_info *c, const union ubifs_key *key, + int lnum, int offs, int len, const struct qstr *nm) +{ + int found, n, err = 0; + struct ubifs_znode *znode; + + mutex_lock(&c->tnc_mutex); + dbg_tnc("LEB %d:%d, name '%.*s', key %s", lnum, offs, nm->len, nm->name, + DBGKEY(key)); + found = lookup_level0_dirty(c, key, &znode, &n); + if (found < 0) { + err = found; + goto out_unlock; + } + + if (found == 1) { + if (c->replaying) + found = fallible_resolve_collision(c, key, &znode, &n, + nm, 1); + else + found = resolve_collision(c, key, &znode, &n, nm); + dbg_tnc("rc returned %d, znode %p, n %d", found, znode, n); + if (found < 0) { + err = found; + goto out_unlock; + } + + /* Ensure the znode is dirtied */ + if (znode->cnext || !ubifs_zn_dirty(znode)) { + znode = dirty_cow_bottom_up(c, znode); + if (IS_ERR(znode)) { + err = PTR_ERR(znode); + goto out_unlock; + } + } + + if (found == 1) { + struct ubifs_zbranch *zbr = &znode->zbranch[n]; + + lnc_free(zbr); + err = ubifs_add_dirt(c, zbr->lnum, zbr->len); + zbr->lnum = lnum; + zbr->offs = offs; + zbr->len = len; + goto out_unlock; + } + } + + if (!found) { + struct ubifs_zbranch zbr; + + zbr.znode = NULL; + zbr.lnum = lnum; + zbr.offs = offs; + zbr.len = len; + key_copy(c, key, &zbr.key); + err = tnc_insert(c, znode, &zbr, n + 1); + if (err) + goto out_unlock; + if (c->replaying) { + /* + * We did not find it in the index so there may be a + * dangling branch still in the index. So we remove it + * by passing 'ubifs_tnc_remove_nm()' the same key but + * an unmatchable name. + */ + struct qstr noname = { .len = 0, .name = "" }; + + err = dbg_check_tnc(c, 0); + mutex_unlock(&c->tnc_mutex); + if (err) + return err; + return ubifs_tnc_remove_nm(c, key, &noname); + } + } + +out_unlock: + if (!err) + err = dbg_check_tnc(c, 0); + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * tnc_delete - delete a znode form TNC. + * @c: UBIFS file-system description object + * @znode: znode to delete from + * @n: zbranch slot number to delete + * + * This function deletes a leaf node from @n-th slot of @znode. Returns zero in + * case of success and a negative error code in case of failure. + */ +static int tnc_delete(struct ubifs_info *c, struct ubifs_znode *znode, int n) +{ + struct ubifs_zbranch *zbr; + struct ubifs_znode *zp; + int i, err; + + /* Delete without merge for now */ + ubifs_assert(znode->level == 0); + ubifs_assert(n >= 0 && n < c->fanout); + dbg_tnc("deleting %s", DBGKEY(&znode->zbranch[n].key)); + + zbr = &znode->zbranch[n]; + lnc_free(zbr); + + err = ubifs_add_dirt(c, zbr->lnum, zbr->len); + if (err) { + dbg_dump_znode(c, znode); + return err; + } + + /* We do not "gap" zbranch slots */ + for (i = n; i < znode->child_cnt - 1; i++) + znode->zbranch[i] = znode->zbranch[i + 1]; + znode->child_cnt -= 1; + + if (znode->child_cnt > 0) + return 0; + + /* + * This was the last zbranch, we have to delete this znode from the + * parent. + */ + + do { + ubifs_assert(!test_bit(OBSOLETE_ZNODE, &znode->flags)); + ubifs_assert(ubifs_zn_dirty(znode)); + + zp = znode->parent; + n = znode->iip; + + atomic_long_dec(&c->dirty_zn_cnt); + + err = insert_old_idx_znode(c, znode); + if (err) + return err; + + if (znode->cnext) { + __set_bit(OBSOLETE_ZNODE, &znode->flags); + atomic_long_inc(&c->clean_zn_cnt); + atomic_long_inc(&ubifs_clean_zn_cnt); + } else + kfree(znode); + znode = zp; + } while (znode->child_cnt == 1); /* while removing last child */ + + /* Remove from znode, entry n - 1 */ + znode->child_cnt -= 1; + ubifs_assert(znode->level != 0); + for (i = n; i < znode->child_cnt; i++) { + znode->zbranch[i] = znode->zbranch[i + 1]; + if (znode->zbranch[i].znode) + znode->zbranch[i].znode->iip = i; + } + + /* + * If this is the root and it has only 1 child then + * collapse the tree. + */ + if (!znode->parent) { + while (znode->child_cnt == 1 && znode->level != 0) { + zp = znode; + zbr = &znode->zbranch[0]; + znode = get_znode(c, znode, 0); + if (IS_ERR(znode)) + return PTR_ERR(znode); + znode = dirty_cow_znode(c, zbr); + if (IS_ERR(znode)) + return PTR_ERR(znode); + znode->parent = NULL; + znode->iip = 0; + if (c->zroot.len) { + err = insert_old_idx(c, c->zroot.lnum, + c->zroot.offs); + if (err) + return err; + } + c->zroot.lnum = zbr->lnum; + c->zroot.offs = zbr->offs; + c->zroot.len = zbr->len; + c->zroot.znode = znode; + ubifs_assert(!test_bit(OBSOLETE_ZNODE, + &zp->flags)); + ubifs_assert(test_bit(DIRTY_ZNODE, &zp->flags)); + atomic_long_dec(&c->dirty_zn_cnt); + + if (zp->cnext) { + __set_bit(OBSOLETE_ZNODE, &zp->flags); + atomic_long_inc(&c->clean_zn_cnt); + atomic_long_inc(&ubifs_clean_zn_cnt); + } else + kfree(zp); + } + } + + return 0; +} + +/** + * ubifs_tnc_remove - remove an index entry of a node. + * @c: UBIFS file-system description object + * @key: key of node + * + * Returns %0 on success or negative error code on failure. + */ +int ubifs_tnc_remove(struct ubifs_info *c, const union ubifs_key *key) +{ + int found, n, err = 0; + struct ubifs_znode *znode; + + mutex_lock(&c->tnc_mutex); + dbg_tnc("key %s", DBGKEY(key)); + found = lookup_level0_dirty(c, key, &znode, &n); + if (found < 0) { + err = found; + goto out_unlock; + } + if (found == 1) + err = tnc_delete(c, znode, n); + if (!err) + err = dbg_check_tnc(c, 0); + +out_unlock: + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * ubifs_tnc_remove_nm - remove an index entry for a "hashed" node. + * @c: UBIFS file-system description object + * @key: key of node + * @nm: directory entry name + * + * Returns %0 on success or negative error code on failure. + */ +int ubifs_tnc_remove_nm(struct ubifs_info *c, const union ubifs_key *key, + const struct qstr *nm) +{ + int n, err; + struct ubifs_znode *znode; + + mutex_lock(&c->tnc_mutex); + dbg_tnc("%.*s, key %s", nm->len, nm->name, DBGKEY(key)); + err = lookup_level0_dirty(c, key, &znode, &n); + if (err < 0) + goto out_unlock; + + if (err) { + if (c->replaying) + err = fallible_resolve_collision(c, key, &znode, &n, + nm, 0); + else + err = resolve_collision(c, key, &znode, &n, nm); + dbg_tnc("rc returned %d, znode %p, n %d", err, znode, n); + if (err < 0) + goto out_unlock; + if (err) { + /* Ensure the znode is dirtied */ + if (znode->cnext || !ubifs_zn_dirty(znode)) { + znode = dirty_cow_bottom_up(c, znode); + if (IS_ERR(znode)) { + err = PTR_ERR(znode); + goto out_unlock; + } + } + err = tnc_delete(c, znode, n); + } + } + +out_unlock: + if (!err) + err = dbg_check_tnc(c, 0); + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * key_in_range - determine if a key falls within a range of keys. + * @c: UBIFS file-system description object + * @key: key to check + * @from_key: lowest key in range + * @to_key: highest key in range + * + * This function returns %1 if the key is in range and %0 otherwise. + */ +static int key_in_range(struct ubifs_info *c, union ubifs_key *key, + union ubifs_key *from_key, union ubifs_key *to_key) +{ + if (keys_cmp(c, key, from_key) < 0) + return 0; + if (keys_cmp(c, key, to_key) > 0) + return 0; + return 1; +} + +/** + * ubifs_tnc_remove_range - remove index entries in range. + * @c: UBIFS file-system description object + * @from_key: lowest key to remove + * @to_key: highest key to remove + * + * This function removes index entries starting at @from_key and ending at + * @to_key. This function returns zero in case of success and a negative error + * code in case of failure. + */ +int ubifs_tnc_remove_range(struct ubifs_info *c, union ubifs_key *from_key, + union ubifs_key *to_key) +{ + int i, n, k, err = 0; + struct ubifs_znode *znode; + union ubifs_key *key; + + mutex_lock(&c->tnc_mutex); + while (1) { + /* Find first level 0 znode that contains keys to remove */ + err = ubifs_lookup_level0(c, from_key, &znode, &n); + if (err < 0) + goto out_unlock; + + if (err) + key = from_key; + else { + err = tnc_next(c, &znode, &n); + if (err == -ENOENT) { + err = 0; + goto out_unlock; + } + if (err < 0) + goto out_unlock; + key = &znode->zbranch[n].key; + if (!key_in_range(c, key, from_key, to_key)) { + err = 0; + goto out_unlock; + } + } + + /* Ensure the znode is dirtied */ + if (znode->cnext || !ubifs_zn_dirty(znode)) { + znode = dirty_cow_bottom_up(c, znode); + if (IS_ERR(znode)) { + err = PTR_ERR(znode); + goto out_unlock; + } + } + + /* Remove all keys in range except the first */ + for (i = n + 1, k = 0; i < znode->child_cnt; i++, k++) { + key = &znode->zbranch[i].key; + if (!key_in_range(c, key, from_key, to_key)) + break; + lnc_free(&znode->zbranch[i]); + err = ubifs_add_dirt(c, znode->zbranch[i].lnum, + znode->zbranch[i].len); + if (err) { + dbg_dump_znode(c, znode); + goto out_unlock; + } + dbg_tnc("removing %s", DBGKEY(key)); + } + if (k) { + for (i = n + 1 + k; i < znode->child_cnt; i++) + znode->zbranch[i - k] = znode->zbranch[i]; + znode->child_cnt -= k; + } + + /* Now delete the first */ + err = tnc_delete(c, znode, n); + if (err) + goto out_unlock; + } + +out_unlock: + if (!err) + err = dbg_check_tnc(c, 0); + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * ubifs_tnc_remove_ino - remove an inode from TNC. + * @c: UBIFS file-system description object + * @inum: inode number to remove + * + * This function remove inode @inum and all the extended attributes associated + * with the anode from TNC and returns zero in case of success or a negative + * error code in case of failure. + */ +int ubifs_tnc_remove_ino(struct ubifs_info *c, ino_t inum) +{ + union ubifs_key key1, key2; + struct ubifs_dent_node *xent, *pxent = NULL; + struct qstr nm = { .name = NULL }; + + dbg_tnc("ino %lu", (unsigned long)inum); + + /* + * Walk all extended attribute entries and remove them together with + * corresponding extended attribute inodes. + */ + lowest_xent_key(c, &key1, inum); + while (1) { + ino_t xattr_inum; + int err; + + xent = ubifs_tnc_next_ent(c, &key1, &nm); + if (IS_ERR(xent)) { + err = PTR_ERR(xent); + if (err == -ENOENT) + break; + return err; + } + + xattr_inum = le64_to_cpu(xent->inum); + dbg_tnc("xent '%s', ino %lu", xent->name, + (unsigned long)xattr_inum); + + nm.name = (char *)xent->name; + nm.len = le16_to_cpu(xent->nlen); + err = ubifs_tnc_remove_nm(c, &key1, &nm); + if (err) { + kfree(xent); + return err; + } + + lowest_ino_key(c, &key1, xattr_inum); + highest_ino_key(c, &key2, xattr_inum); + err = ubifs_tnc_remove_range(c, &key1, &key2); + if (err) { + kfree(xent); + return err; + } + + kfree(pxent); + pxent = xent; + key_read(c, &xent->key, &key1); + } + + kfree(pxent); + lowest_ino_key(c, &key1, inum); + highest_ino_key(c, &key2, inum); + + return ubifs_tnc_remove_range(c, &key1, &key2); +} + +/** + * ubifs_tnc_next_ent - walk directory or extended attribute entries. + * @c: UBIFS file-system description object + * @key: key of last entry + * @nm: name of last entry found or %NULL + * + * This function finds and reads the next directory or extended attribute entry + * after the given key (@key) if there is one. @nm is used to resolve + * collisions. + * + * If the name of the current entry is not known and only the key is known, + * @nm->name has to be %NULL. In this case the semantics of this function is a + * little bit different and it returns the entry corresponding to this key, not + * the next one. If the key was not found, the closest "right" entry is + * returned. + * + * If the fist entry has to be found, @key has to contain the lowest possible + * key value for this inode and @name has to be %NULL. + * + * This function returns the found directory or extended attribute entry node + * in case of success, %-ENOENT is returned if no entry was found, and a + * negative error code is returned in case of failure. + */ +struct ubifs_dent_node *ubifs_tnc_next_ent(struct ubifs_info *c, + union ubifs_key *key, + const struct qstr *nm) +{ + int n, err, type = key_type(c, key); + struct ubifs_znode *znode; + struct ubifs_dent_node *dent; + struct ubifs_zbranch *zbr; + union ubifs_key *dkey; + + dbg_tnc("%s %s", nm->name ? (char *)nm->name : "(lowest)", DBGKEY(key)); + ubifs_assert(is_hash_key(c, key)); + + mutex_lock(&c->tnc_mutex); + err = ubifs_lookup_level0(c, key, &znode, &n); + if (unlikely(err < 0)) + goto out_unlock; + + if (nm->name) { + if (err) { + /* Handle collisions */ + err = resolve_collision(c, key, &znode, &n, nm); + dbg_tnc("rc returned %d, znode %p, n %d", + err, znode, n); + if (unlikely(err < 0)) + goto out_unlock; + } + + /* Now find next entry */ + err = tnc_next(c, &znode, &n); + if (unlikely(err)) + goto out_unlock; + } else { + /* + * The full name of the entry was not given, in which case the + * behavior of this function is a little different and it + * returns current entry, not the next one. + */ + if (!err) { + /* + * However, the given key does not exist in the TNC + * tree and @znode/@n variables contain the closest + * "preceding" element. Switch to the next one. + */ + err = tnc_next(c, &znode, &n); + if (err) + goto out_unlock; + } + } + + zbr = &znode->zbranch[n]; + dent = kmalloc(zbr->len, GFP_NOFS); + if (unlikely(!dent)) { + err = -ENOMEM; + goto out_unlock; + } + + /* + * The above 'tnc_next()' call could lead us to the next inode, check + * this. + */ + dkey = &zbr->key; + if (key_inum(c, dkey) != key_inum(c, key) || + key_type(c, dkey) != type) { + err = -ENOENT; + goto out_free; + } + + err = tnc_read_node_nm(c, zbr, dent); + if (unlikely(err)) + goto out_free; + + mutex_unlock(&c->tnc_mutex); + return dent; + +out_free: + kfree(dent); +out_unlock: + mutex_unlock(&c->tnc_mutex); + return ERR_PTR(err); +} diff --git a/fs/ubifs/tnc_commit.c b/fs/ubifs/tnc_commit.c new file mode 100644 index 0000000..8ac76b1 --- /dev/null +++ b/fs/ubifs/tnc_commit.c @@ -0,0 +1,1102 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* This file implements TNC functions for committing */ + +#include "ubifs.h" + +/** + * make_idx_node - make an index node for fill-the-gaps method of TNC commit. + * @c: UBIFS file-system description object + * @idx: buffer in which to place new index node + * @znode: znode from which to make new index node + * @lnum: LEB number where new index node will be written + * @offs: offset where new index node will be written + * @len: length of new index node + */ +static int make_idx_node(struct ubifs_info *c, struct ubifs_idx_node *idx, + struct ubifs_znode *znode, int lnum, int offs, int len) +{ + struct ubifs_znode *zp; + int i, err; + + /* Make index node */ + idx->ch.node_type = UBIFS_IDX_NODE; + idx->child_cnt = cpu_to_le16(znode->child_cnt); + idx->level = cpu_to_le16(znode->level); + for (i = 0; i < znode->child_cnt; i++) { + struct ubifs_branch *br = ubifs_idx_branch(c, idx, i); + struct ubifs_zbranch *zbr = &znode->zbranch[i]; + + key_write_idx(c, &zbr->key, &br->key); + br->lnum = cpu_to_le32(zbr->lnum); + br->offs = cpu_to_le32(zbr->offs); + br->len = cpu_to_le32(zbr->len); + if (!zbr->lnum || !zbr->len) { + ubifs_err("bad ref in znode"); + dbg_dump_znode(c, znode); + if (zbr->znode) + dbg_dump_znode(c, zbr->znode); + } + } + ubifs_prepare_node(c, idx, len, 0); + +#ifdef CONFIG_UBIFS_FS_DEBUG + znode->lnum = lnum; + znode->offs = offs; + znode->len = len; +#endif + + err = insert_old_idx_znode(c, znode); + + /* Update the parent */ + zp = znode->parent; + if (zp) { + struct ubifs_zbranch *zbr; + + zbr = &zp->zbranch[znode->iip]; + zbr->lnum = lnum; + zbr->offs = offs; + zbr->len = len; + } else { + c->zroot.lnum = lnum; + c->zroot.offs = offs; + c->zroot.len = len; + } + c->calc_idx_sz += ALIGN(len, 8); + + atomic_long_dec(&c->dirty_zn_cnt); + + ubifs_assert(ubifs_zn_dirty(znode)); + ubifs_assert(test_bit(COW_ZNODE, &znode->flags)); + + __clear_bit(DIRTY_ZNODE, &znode->flags); + __clear_bit(COW_ZNODE, &znode->flags); + + return err; +} + +/** + * fill_gap - make index nodes in gaps in dirty index LEBs. + * @c: UBIFS file-system description object + * @lnum: LEB number that gap appears in + * @gap_start: offset of start of gap + * @gap_end: offset of end of gap + * @dirt: adds dirty space to this + * + * This function returns the number of index nodes written into the gap. + */ +static int fill_gap(struct ubifs_info *c, int lnum, int gap_start, int gap_end, + int *dirt) +{ + int len, gap_remains, gap_pos, written, pad_len; + + ubifs_assert((gap_start & 7) == 0); + ubifs_assert((gap_end & 7) == 0); + ubifs_assert(gap_end >= gap_start); + + gap_remains = gap_end - gap_start; + if (!gap_remains) + return 0; + gap_pos = gap_start; + written = 0; + while (c->enext) { + len = ubifs_idx_node_sz(c, c->enext->child_cnt); + if (len < gap_remains) { + struct ubifs_znode *znode = c->enext; + const int alen = ALIGN(len, 8); + int err; + + ubifs_assert(alen <= gap_remains); + err = make_idx_node(c, c->ileb_buf + gap_pos, znode, + lnum, gap_pos, len); + if (err) + return err; + gap_remains -= alen; + gap_pos += alen; + c->enext = znode->cnext; + if (c->enext == c->cnext) + c->enext = NULL; + written += 1; + } else + break; + } + if (gap_end == c->leb_size) { + c->ileb_len = ALIGN(gap_pos, c->min_io_size); + /* Pad to end of min_io_size */ + pad_len = c->ileb_len - gap_pos; + } else + /* Pad to end of gap */ + pad_len = gap_remains; + dbg_gc("LEB %d:%d to %d len %d nodes written %d wasted bytes %d", + lnum, gap_start, gap_end, gap_end - gap_start, written, pad_len); + ubifs_pad(c, c->ileb_buf + gap_pos, pad_len); + *dirt += pad_len; + return written; +} + +/** + * find_old_idx - find an index node obsoleted since the last commit start. + * @c: UBIFS file-system description object + * @lnum: LEB number of obsoleted index node + * @offs: offset of obsoleted index node + * + * Returns %1 if found and %0 otherwise. + */ +static int find_old_idx(struct ubifs_info *c, int lnum, int offs) +{ + struct ubifs_old_idx *o; + struct rb_node *p; + + p = c->old_idx.rb_node; + while (p) { + o = rb_entry(p, struct ubifs_old_idx, rb); + if (lnum < o->lnum) + p = p->rb_left; + else if (lnum > o->lnum) + p = p->rb_right; + else if (offs < o->offs) + p = p->rb_left; + else if (offs > o->offs) + p = p->rb_right; + else + return 1; + } + return 0; +} + +/** + * is_idx_node_in_use - determine if an index node can be overwritten. + * @c: UBIFS file-system description object + * @key: key of index node + * @level: index node level + * @lnum: LEB number of index node + * @offs: offset of index node + * + * If @key / @lnum / @offs identify an index node that was not part of the old + * index, then this function returns %0 (obsolete). Else if the index node was + * part of the old index but is now dirty %1 is returned, else if it is clean %2 + * is returned. A negative error code is returned on failure. + */ +static int is_idx_node_in_use(struct ubifs_info *c, union ubifs_key *key, + int level, int lnum, int offs) +{ + int ret; + + ret = is_idx_node_in_tnc(c, key, level, lnum, offs); + if (ret < 0) + return ret; /* Error code */ + if (ret == 0) + if (find_old_idx(c, lnum, offs)) + return 1; + return ret; +} + +/** + * layout_leb_in_gaps - layout index nodes using in-the-gaps method. + * @c: UBIFS file-system description object + * @p: return LEB number here + * + * This function lays out new index nodes for dirty znodes using in-the-gaps + * method of TNC commit. + * This function merely puts the next znode into the next gap, making no attempt + * to try to maximise the number of znodes that fit. + * This function returns the number of index nodes written into the gaps, or a + * negative error code on failure. + */ +static int layout_leb_in_gaps(struct ubifs_info *c, int *p) +{ + struct ubifs_scan_leb *sleb; + struct ubifs_scan_node *snod; + int lnum, dirt = 0, gap_start, gap_end, err, written, tot_written; + + tot_written = 0; + /* Get an index LEB with lots of obsolete index nodes */ + lnum = ubifs_find_dirty_idx_leb(c); + if (lnum < 0) + /* + * There also may be dirt in the index head that could be + * filled, however we do not check there at present. + */ + return lnum; /* Error code */ + *p = lnum; + dbg_gc("LEB %d", lnum); + /* + * Scan the index LEB. We use the generic scan for this even though + * it is more comprehensive and less efficient than is needed for this + * purpose. + */ + sleb = ubifs_scan(c, lnum, 0, c->ileb_buf); + c->ileb_len = 0; + if (IS_ERR(sleb)) + return PTR_ERR(sleb); + gap_start = 0; + list_for_each_entry(snod, &sleb->nodes, list) { + struct ubifs_idx_node *idx; + int in_use, level; + + ubifs_assert(snod->type == UBIFS_IDX_NODE); + idx = snod->node; + key_read(c, ubifs_idx_key(c, idx), &snod->key); + level = le16_to_cpu(idx->level); + /* Determine if the index node is in use (not obsolete) */ + in_use = is_idx_node_in_use(c, &snod->key, level, lnum, + snod->offs); + if (in_use < 0) { + ubifs_scan_destroy(sleb); + return in_use; /* Error code */ + } + if (in_use) { + if (in_use == 1) + dirt += ALIGN(snod->len, 8); + /* + * The obsolete index nodes form gaps that can be + * overwritten. This gap has ended because we have + * found an index node that is still in use + * i.e. not obsolete + */ + gap_end = snod->offs; + /* Try to fill gap */ + written = fill_gap(c, lnum, gap_start, gap_end, &dirt); + if (written < 0) { + ubifs_scan_destroy(sleb); + return written; /* Error code */ + } + tot_written += written; + gap_start = ALIGN(snod->offs + snod->len, 8); + } + } + ubifs_scan_destroy(sleb); + c->ileb_len = c->leb_size; + gap_end = c->leb_size; + /* Try to fill gap */ + written = fill_gap(c, lnum, gap_start, gap_end, &dirt); + if (written < 0) + return written; /* Error code */ + tot_written += written; + if (tot_written == 0) { + struct ubifs_lprops lp; + + dbg_gc("LEB %d wrote %d index nodes", lnum, tot_written); + err = ubifs_read_one_lp(c, lnum, &lp); + if (err) + return err; + if (lp.free == c->leb_size) { + /* + * We must have snatched this LEB from the idx_gc list + * so we need to correct the free and dirty space. + */ + err = ubifs_change_one_lp(c, lnum, + c->leb_size - c->ileb_len, + dirt, 0, 0, 0); + if (err) + return err; + } + return 0; + } + err = ubifs_change_one_lp(c, lnum, c->leb_size - c->ileb_len, dirt, + 0, 0, 0); + if (err) + return err; + err = ubifs_leb_change(c, lnum, c->ileb_buf, c->ileb_len, + UBI_SHORTTERM); + if (err) + return err; + dbg_gc("LEB %d wrote %d index nodes", lnum, tot_written); + return tot_written; +} + +/** + * get_leb_cnt - calculate the number of empty LEBs needed to commit. + * @c: UBIFS file-system description object + * @cnt: number of znodes to commit + * + * This function returns the number of empty LEBs needed to commit @cnt znodes + * to the current index head. The number is not exact and may be more than + * needed. + */ +static int get_leb_cnt(struct ubifs_info *c, int cnt) +{ + int d; + + /* Assume maximum index node size (i.e. overestimate space needed) */ + cnt -= (c->leb_size - c->ihead_offs) / c->max_idx_node_sz; + if (cnt < 0) + cnt = 0; + d = c->leb_size / c->max_idx_node_sz; + return DIV_ROUND_UP(cnt, d); +} + +/** + * layout_in_gaps - in-the-gaps method of committing TNC. + * @c: UBIFS file-system description object + * @cnt: number of dirty znodes to commit. + * + * This function lays out new index nodes for dirty znodes using in-the-gaps + * method of TNC commit. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int layout_in_gaps(struct ubifs_info *c, int cnt) +{ + int err, leb_needed_cnt, written, *p; + + dbg_gc("%d znodes to write", cnt); + + c->gap_lebs = kmalloc(sizeof(int) * (c->lst.idx_lebs + 1), GFP_NOFS); + if (!c->gap_lebs) + return -ENOMEM; + + p = c->gap_lebs; + do { + ubifs_assert(p < c->gap_lebs + sizeof(int) * c->lst.idx_lebs); + written = layout_leb_in_gaps(c, p); + if (written < 0) { + err = written; + if (err != -ENOSPC) { + kfree(c->gap_lebs); + c->gap_lebs = NULL; + return err; + } + if (!dbg_force_in_the_gaps_enabled) { + /* + * Do not print scary warnings if the debugging + * option which forces in-the-gaps is enabled. + */ + ubifs_err("out of space"); + spin_lock(&c->space_lock); + dbg_dump_budg(c); + spin_unlock(&c->space_lock); + dbg_dump_lprops(c); + } + /* Try to commit anyway */ + err = 0; + break; + } + p++; + cnt -= written; + leb_needed_cnt = get_leb_cnt(c, cnt); + dbg_gc("%d znodes remaining, need %d LEBs, have %d", cnt, + leb_needed_cnt, c->ileb_cnt); + } while (leb_needed_cnt > c->ileb_cnt); + + *p = -1; + return 0; +} + +/** + * layout_in_empty_space - layout index nodes in empty space. + * @c: UBIFS file-system description object + * + * This function lays out new index nodes for dirty znodes using empty LEBs. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int layout_in_empty_space(struct ubifs_info *c) +{ + struct ubifs_znode *znode, *cnext, *zp; + int lnum, offs, len, next_len, buf_len, buf_offs, used, avail; + int wlen, blen, err; + + cnext = c->enext; + if (!cnext) + return 0; + + lnum = c->ihead_lnum; + buf_offs = c->ihead_offs; + + buf_len = ubifs_idx_node_sz(c, c->fanout); + buf_len = ALIGN(buf_len, c->min_io_size); + used = 0; + avail = buf_len; + + /* Ensure there is enough room for first write */ + next_len = ubifs_idx_node_sz(c, cnext->child_cnt); + if (buf_offs + next_len > c->leb_size) + lnum = -1; + + while (1) { + znode = cnext; + + len = ubifs_idx_node_sz(c, znode->child_cnt); + + /* Determine the index node position */ + if (lnum == -1) { + if (c->ileb_nxt >= c->ileb_cnt) { + ubifs_err("out of space"); + return -ENOSPC; + } + lnum = c->ilebs[c->ileb_nxt++]; + buf_offs = 0; + used = 0; + avail = buf_len; + } + + offs = buf_offs + used; + +#ifdef CONFIG_UBIFS_FS_DEBUG + znode->lnum = lnum; + znode->offs = offs; + znode->len = len; +#endif + + /* Update the parent */ + zp = znode->parent; + if (zp) { + struct ubifs_zbranch *zbr; + int i; + + i = znode->iip; + zbr = &zp->zbranch[i]; + zbr->lnum = lnum; + zbr->offs = offs; + zbr->len = len; + } else { + c->zroot.lnum = lnum; + c->zroot.offs = offs; + c->zroot.len = len; + } + c->calc_idx_sz += ALIGN(len, 8); + + /* + * Once lprops is updated, we can decrease the dirty znode count + * but it is easier to just do it here. + */ + atomic_long_dec(&c->dirty_zn_cnt); + + /* + * Calculate the next index node length to see if there is + * enough room for it + */ + cnext = znode->cnext; + if (cnext == c->cnext) + next_len = 0; + else + next_len = ubifs_idx_node_sz(c, cnext->child_cnt); + + if (c->min_io_size == 1) { + buf_offs += ALIGN(len, 8); + if (next_len) { + if (buf_offs + next_len <= c->leb_size) + continue; + err = ubifs_update_one_lp(c, lnum, 0, + c->leb_size - buf_offs, 0, 0); + if (err) + return err; + lnum = -1; + continue; + } + err = ubifs_update_one_lp(c, lnum, + c->leb_size - buf_offs, 0, 0, 0); + if (err) + return err; + break; + } + + /* Update buffer positions */ + wlen = used + len; + used += ALIGN(len, 8); + avail -= ALIGN(len, 8); + + if (next_len != 0 && + buf_offs + used + next_len <= c->leb_size && + avail > 0) + continue; + + if (avail <= 0 && next_len && + buf_offs + used + next_len <= c->leb_size) + blen = buf_len; + else + blen = ALIGN(wlen, c->min_io_size); + + /* The buffer is full or there are no more znodes to do */ + buf_offs += blen; + if (next_len) { + if (buf_offs + next_len > c->leb_size) { + err = ubifs_update_one_lp(c, lnum, + c->leb_size - buf_offs, blen - used, + 0, 0); + if (err) + return err; + lnum = -1; + } + used -= blen; + if (used < 0) + used = 0; + avail = buf_len - used; + continue; + } + err = ubifs_update_one_lp(c, lnum, c->leb_size - buf_offs, + blen - used, 0, 0); + if (err) + return err; + break; + } + +#ifdef CONFIG_UBIFS_FS_DEBUG + c->new_ihead_lnum = lnum; + c->new_ihead_offs = buf_offs; +#endif + + return 0; +} + +/** + * layout_commit - determine positions of index nodes to commit. + * @c: UBIFS file-system description object + * @no_space: indicates that insufficient empty LEBs were allocated + * @cnt: number of znodes to commit + * + * Calculate and update the positions of index nodes to commit. If there were + * an insufficient number of empty LEBs allocated, then index nodes are placed + * into the gaps created by obsolete index nodes in non-empty index LEBs. For + * this purpose, an obsolete index node is one that was not in the index as at + * the end of the last commit. To write "in-the-gaps" requires that those index + * LEBs are updated atomically in-place. + */ +static int layout_commit(struct ubifs_info *c, int no_space, int cnt) +{ + int err; + + if (no_space) { + err = layout_in_gaps(c, cnt); + if (err) + return err; + } + err = layout_in_empty_space(c); + return err; +} + +/** + * find_first_dirty - find first dirty znode. + * @znode: znode to begin searching from + */ +static struct ubifs_znode *find_first_dirty(struct ubifs_znode *znode) +{ + int i, cont; + + if (!znode) + return NULL; + + while (1) { + if (znode->level == 0) { + if (ubifs_zn_dirty(znode)) + return znode; + return NULL; + } + cont = 0; + for (i = 0; i < znode->child_cnt; i++) { + struct ubifs_zbranch *zbr = &znode->zbranch[i]; + + if (zbr->znode && ubifs_zn_dirty(zbr->znode)) { + znode = zbr->znode; + cont = 1; + break; + } + } + if (!cont) { + if (ubifs_zn_dirty(znode)) + return znode; + return NULL; + } + } +} + +/** + * find_next_dirty - find next dirty znode. + * @znode: znode to begin searching from + */ +static struct ubifs_znode *find_next_dirty(struct ubifs_znode *znode) +{ + int n = znode->iip + 1; + + znode = znode->parent; + if (!znode) + return NULL; + for (; n < znode->child_cnt; n++) { + struct ubifs_zbranch *zbr = &znode->zbranch[n]; + + if (zbr->znode && ubifs_zn_dirty(zbr->znode)) + return find_first_dirty(zbr->znode); + } + return znode; +} + +/** + * get_znodes_to_commit - create list of dirty znodes to commit. + * @c: UBIFS file-system description object + * + * This function returns the number of znodes to commit. + */ +static int get_znodes_to_commit(struct ubifs_info *c) +{ + struct ubifs_znode *znode, *cnext; + int cnt = 0; + + c->cnext = find_first_dirty(c->zroot.znode); + znode = c->enext = c->cnext; + if (!znode) { + dbg_cmt("no znodes to commit"); + return 0; + } + cnt += 1; + while (1) { + ubifs_assert(!test_bit(COW_ZNODE, &znode->flags)); + __set_bit(COW_ZNODE, &znode->flags); + znode->alt = 0; + cnext = find_next_dirty(znode); + if (!cnext) { + znode->cnext = c->cnext; + break; + } + znode->cnext = cnext; + znode = cnext; + cnt += 1; + } + dbg_cmt("committing %d znodes", cnt); + ubifs_assert(cnt == atomic_long_read(&c->dirty_zn_cnt)); + return cnt; +} + +/** + * alloc_idx_lebs - allocate empty LEBs to be used to commit. + * @c: UBIFS file-system description object + * @cnt: number of znodes to commit + * + * This function returns %-ENOSPC if it cannot allocate a sufficient number of + * empty LEBs. %0 is returned on success, otherwise a negative error code + * is returned. + */ +static int alloc_idx_lebs(struct ubifs_info *c, int cnt) +{ + int i, leb_cnt, lnum; + + c->ileb_cnt = 0; + c->ileb_nxt = 0; + leb_cnt = get_leb_cnt(c, cnt); + dbg_cmt("need about %d empty LEBS for TNC commit", leb_cnt); + if (!leb_cnt) + return 0; + c->ilebs = kmalloc(leb_cnt * sizeof(int), GFP_NOFS); + if (!c->ilebs) + return -ENOMEM; + for (i = 0; i < leb_cnt; i++) { + lnum = ubifs_find_free_leb_for_idx(c); + if (lnum < 0) + return lnum; + c->ilebs[c->ileb_cnt++] = lnum; + dbg_cmt("LEB %d", lnum); + } + if (dbg_force_in_the_gaps()) + return -ENOSPC; + return 0; +} + +/** + * free_unused_idx_lebs - free unused LEBs that were allocated for the commit. + * @c: UBIFS file-system description object + * + * It is possible that we allocate more empty LEBs for the commit than we need. + * This functions frees the surplus. + * + * This function returns %0 on success and a negative error code on failure. + */ +static int free_unused_idx_lebs(struct ubifs_info *c) +{ + int i, err = 0, lnum, er; + + for (i = c->ileb_nxt; i < c->ileb_cnt; i++) { + lnum = c->ilebs[i]; + dbg_cmt("LEB %d", lnum); + er = ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0, + LPROPS_INDEX | LPROPS_TAKEN, 0); + if (!err) + err = er; + } + return err; +} + +/** + * free_idx_lebs - free unused LEBs after commit end. + * @c: UBIFS file-system description object + * + * This function returns %0 on success and a negative error code on failure. + */ +static int free_idx_lebs(struct ubifs_info *c) +{ + int err; + + err = free_unused_idx_lebs(c); + kfree(c->ilebs); + c->ilebs = NULL; + return err; +} + +/** + * ubifs_tnc_start_commit - start TNC commit. + * @c: UBIFS file-system description object + * @zroot: new index root position is returned here + * + * This function prepares the list of indexing nodes to commit and lays out + * their positions on flash. If there is not enough free space it uses the + * in-gap commit method. Returns zero in case of success and a negative error + * code in case of failure. + */ +int ubifs_tnc_start_commit(struct ubifs_info *c, struct ubifs_zbranch *zroot) +{ + int err = 0, cnt; + + mutex_lock(&c->tnc_mutex); + err = dbg_check_tnc(c, 1); + if (err) + goto out; + cnt = get_znodes_to_commit(c); + if (cnt != 0) { + int no_space = 0; + + err = alloc_idx_lebs(c, cnt); + if (err == -ENOSPC) + no_space = 1; + else if (err) + goto out_free; + err = layout_commit(c, no_space, cnt); + if (err) + goto out_free; + ubifs_assert(atomic_long_read(&c->dirty_zn_cnt) == 0); + err = free_unused_idx_lebs(c); + if (err) + goto out; + } + destroy_old_idx(c); + memcpy(zroot, &c->zroot, sizeof(struct ubifs_zbranch)); + + err = ubifs_save_dirty_idx_lnums(c); + if (err) + goto out; + + spin_lock(&c->space_lock); + /* + * Although we have not finished committing yet, update size of the + * committed index ('c->old_idx_sz') and zero out the index growth + * budget. It is OK to do this now, because we've reserved all the + * space which is needed to commit the index, and it is save for the + * budgeting subsystem to assume the index is already committed, + * even though it is not. + */ + c->old_idx_sz = c->calc_idx_sz; + c->budg_uncommitted_idx = 0; + spin_unlock(&c->space_lock); + mutex_unlock(&c->tnc_mutex); + + dbg_cmt("number of index LEBs %d", c->lst.idx_lebs); + dbg_cmt("size of index %llu", c->calc_idx_sz); + return err; + +out_free: + free_idx_lebs(c); +out: + mutex_unlock(&c->tnc_mutex); + return err; +} + +/** + * write_index - write index nodes. + * @c: UBIFS file-system description object + * + * This function writes the index nodes whose positions were laid out in the + * layout_in_empty_space function. + */ +static int write_index(struct ubifs_info *c) +{ + struct ubifs_idx_node *idx; + struct ubifs_znode *znode, *cnext; + int i, lnum, offs, len, next_len, buf_len, buf_offs, used; + int avail, wlen, err, lnum_pos = 0; + + cnext = c->enext; + if (!cnext) + return 0; + + /* + * Always write index nodes to the index head so that index nodes and + * other types of nodes are never mixed in the same erase block. + */ + lnum = c->ihead_lnum; + buf_offs = c->ihead_offs; + + /* Allocate commit buffer */ + buf_len = ALIGN(c->max_idx_node_sz, c->min_io_size); + used = 0; + avail = buf_len; + + /* Ensure there is enough room for first write */ + next_len = ubifs_idx_node_sz(c, cnext->child_cnt); + if (buf_offs + next_len > c->leb_size) { + err = ubifs_update_one_lp(c, lnum, LPROPS_NC, 0, 0, + LPROPS_TAKEN); + if (err) + return err; + lnum = -1; + } + + while (1) { + cond_resched(); + + znode = cnext; + idx = c->cbuf + used; + + /* Make index node */ + idx->ch.node_type = UBIFS_IDX_NODE; + idx->child_cnt = cpu_to_le16(znode->child_cnt); + idx->level = cpu_to_le16(znode->level); + for (i = 0; i < znode->child_cnt; i++) { + struct ubifs_branch *br = ubifs_idx_branch(c, idx, i); + struct ubifs_zbranch *zbr = &znode->zbranch[i]; + + key_write_idx(c, &zbr->key, &br->key); + br->lnum = cpu_to_le32(zbr->lnum); + br->offs = cpu_to_le32(zbr->offs); + br->len = cpu_to_le32(zbr->len); + if (!zbr->lnum || !zbr->len) { + ubifs_err("bad ref in znode"); + dbg_dump_znode(c, znode); + if (zbr->znode) + dbg_dump_znode(c, zbr->znode); + } + } + len = ubifs_idx_node_sz(c, znode->child_cnt); + ubifs_prepare_node(c, idx, len, 0); + + /* Determine the index node position */ + if (lnum == -1) { + lnum = c->ilebs[lnum_pos++]; + buf_offs = 0; + used = 0; + avail = buf_len; + } + offs = buf_offs + used; + +#ifdef CONFIG_UBIFS_FS_DEBUG + if (lnum != znode->lnum || offs != znode->offs || + len != znode->len) { + ubifs_err("inconsistent znode posn"); + return -EINVAL; + } +#endif + + /* Grab some stuff from znode while we still can */ + cnext = znode->cnext; + + ubifs_assert(ubifs_zn_dirty(znode)); + ubifs_assert(test_bit(COW_ZNODE, &znode->flags)); + + /* + * It is important that other threads should see %DIRTY_ZNODE + * flag cleared before %COW_ZNODE. Specifically, it matters in + * the 'dirty_cow_znode()' function. This is the reason for the + * first barrier. Also, we want the bit changes to be seen to + * other threads ASAP, to avoid unnecesarry copying, which is + * the reason for the second barrier. + */ + clear_bit(DIRTY_ZNODE, &znode->flags); + smp_mb__before_clear_bit(); + clear_bit(COW_ZNODE, &znode->flags); + smp_mb__after_clear_bit(); + + /* Do not access znode from this point on */ + + /* Update buffer positions */ + wlen = used + len; + used += ALIGN(len, 8); + avail -= ALIGN(len, 8); + + /* + * Calculate the next index node length to see if there is + * enough room for it + */ + if (cnext == c->cnext) + next_len = 0; + else + next_len = ubifs_idx_node_sz(c, cnext->child_cnt); + + if (c->min_io_size == 1) { + /* + * Write the prepared index node immediately if there is + * no minimum IO size + */ + err = ubifs_leb_write(c, lnum, c->cbuf, buf_offs, + wlen, UBI_SHORTTERM); + if (err) + return err; + buf_offs += ALIGN(wlen, 8); + if (next_len) { + used = 0; + avail = buf_len; + if (buf_offs + next_len > c->leb_size) { + err = ubifs_update_one_lp(c, lnum, + LPROPS_NC, 0, 0, LPROPS_TAKEN); + if (err) + return err; + lnum = -1; + } + continue; + } + } else { + int blen, nxt_offs = buf_offs + used + next_len; + + if (next_len && nxt_offs <= c->leb_size) { + if (avail > 0) + continue; + else + blen = buf_len; + } else { + wlen = ALIGN(wlen, 8); + blen = ALIGN(wlen, c->min_io_size); + ubifs_pad(c, c->cbuf + wlen, blen - wlen); + } + /* + * The buffer is full or there are no more znodes + * to do + */ + err = ubifs_leb_write(c, lnum, c->cbuf, buf_offs, + blen, UBI_SHORTTERM); + if (err) + return err; + buf_offs += blen; + if (next_len) { + if (nxt_offs > c->leb_size) { + err = ubifs_update_one_lp(c, lnum, + LPROPS_NC, 0, 0, LPROPS_TAKEN); + if (err) + return err; + lnum = -1; + } + used -= blen; + if (used < 0) + used = 0; + avail = buf_len - used; + memmove(c->cbuf, c->cbuf + blen, used); + continue; + } + } + break; + } + +#ifdef CONFIG_UBIFS_FS_DEBUG + if (lnum != c->new_ihead_lnum || buf_offs != c->new_ihead_offs) { + ubifs_err("inconsistent ihead"); + return -EINVAL; + } +#endif + + c->ihead_lnum = lnum; + c->ihead_offs = buf_offs; + + return 0; +} + +/** + * free_obsolete_znodes - free obsolete znodes. + * @c: UBIFS file-system description object + * + * At the end of commit end, obsolete znodes are freed. + */ +static void free_obsolete_znodes(struct ubifs_info *c) +{ + struct ubifs_znode *znode, *cnext; + + cnext = c->cnext; + do { + znode = cnext; + cnext = znode->cnext; + if (test_bit(OBSOLETE_ZNODE, &znode->flags)) + kfree(znode); + else { + znode->cnext = NULL; + atomic_long_inc(&c->clean_zn_cnt); + atomic_long_inc(&ubifs_clean_zn_cnt); + } + } while (cnext != c->cnext); +} + +/** + * return_gap_lebs - return LEBs used by the in-gap commit method. + * @c: UBIFS file-system description object + * + * This function clears the "taken" flag for the LEBs which were used by the + * "commit in-the-gaps" method. + */ +static int return_gap_lebs(struct ubifs_info *c) +{ + int *p, err; + + if (!c->gap_lebs) + return 0; + + dbg_cmt(""); + for (p = c->gap_lebs; *p != -1; p++) { + err = ubifs_change_one_lp(c, *p, LPROPS_NC, LPROPS_NC, 0, + LPROPS_TAKEN, 0); + if (err) + return err; + } + + kfree(c->gap_lebs); + c->gap_lebs = NULL; + return 0; +} + +/** + * ubifs_tnc_end_commit - update the TNC for commit end. + * @c: UBIFS file-system description object + * + * Write the dirty znodes. + */ +int ubifs_tnc_end_commit(struct ubifs_info *c) +{ + int err; + + if (!c->cnext) + return 0; + + err = return_gap_lebs(c); + if (err) + return err; + + err = write_index(c); + if (err) + return err; + + mutex_lock(&c->tnc_mutex); + + dbg_cmt("TNC height is %d", c->zroot.znode->level + 1); + + free_obsolete_znodes(c); + + c->cnext = NULL; + kfree(c->ilebs); + c->ilebs = NULL; + + mutex_unlock(&c->tnc_mutex); + + return 0; +} diff --git a/fs/ubifs/tnc_misc.c b/fs/ubifs/tnc_misc.c new file mode 100644 index 0000000..955219f --- /dev/null +++ b/fs/ubifs/tnc_misc.c @@ -0,0 +1,435 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Adrian Hunter + * Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * This file contains miscelanious TNC-related functions shared betweend + * different files. This file does not form any logically separate TNC + * sub-system. The file was created because there is a lot of TNC code and + * putting it all in one file would make that file too big and unreadable. + */ + +#include "ubifs.h" + +/** + * ubifs_tnc_levelorder_next - next TNC tree element in levelorder traversal. + * @zr: root of the subtree to traverse + * @znode: previous znode + * + * This function implements levelorder TNC traversal. The LNC is ignored. + * Returns the next element or %NULL if @znode is already the last one. + */ +struct ubifs_znode *ubifs_tnc_levelorder_next(struct ubifs_znode *zr, + struct ubifs_znode *znode) +{ + int level, iip, level_search = 0; + struct ubifs_znode *zn; + + ubifs_assert(zr); + + if (unlikely(!znode)) + return zr; + + if (unlikely(znode == zr)) { + if (znode->level == 0) + return NULL; + return ubifs_tnc_find_child(zr, 0); + } + + level = znode->level; + + iip = znode->iip; + while (1) { + ubifs_assert(znode->level <= zr->level); + + /* + * First walk up until there is a znode with next branch to + * look at. + */ + while (znode->parent != zr && iip >= znode->parent->child_cnt) { + znode = znode->parent; + iip = znode->iip; + } + + if (unlikely(znode->parent == zr && + iip >= znode->parent->child_cnt)) { + /* This level is done, switch to the lower one */ + level -= 1; + if (level_search || level < 0) + /* + * We were already looking for znode at lower + * level ('level_search'). As we are here + * again, it just does not exist. Or all levels + * were finished ('level < 0'). + */ + return NULL; + + level_search = 1; + iip = -1; + znode = ubifs_tnc_find_child(zr, 0); + ubifs_assert(znode); + } + + /* Switch to the next index */ + zn = ubifs_tnc_find_child(znode->parent, iip + 1); + if (!zn) { + /* No more children to look at, we have walk up */ + iip = znode->parent->child_cnt; + continue; + } + + /* Walk back down to the level we came from ('level') */ + while (zn->level != level) { + znode = zn; + zn = ubifs_tnc_find_child(zn, 0); + if (!zn) { + /* + * This path is not too deep so it does not + * reach 'level'. Try next path. + */ + iip = znode->iip; + break; + } + } + + if (zn) { + ubifs_assert(zn->level >= 0); + return zn; + } + } +} + +/** + * ubifs_search_zbranch - search znode branch. + * @c: UBIFS file-system description object + * @znode: znode to search in + * @key: key to search for + * @n: znode branch slot number is returned here + * + * This is a helper function which search branch with key @key in @znode using + * binary search. The result of the search may be: + * o exact match, then %1 is returned, and the slot number of the branch is + * stored in @n; + * o no exact match, then %0 is returned and the slot number of the left + * closest branch is returned in @n; the slot if all keys in this znode are + * greater than @key, then %-1 is returned in @n. + */ +int ubifs_search_zbranch(const struct ubifs_info *c, + const struct ubifs_znode *znode, + const union ubifs_key *key, int *n) +{ + int beg = 0, end = znode->child_cnt, uninitialized_var(mid); + int uninitialized_var(cmp); + const struct ubifs_zbranch *zbr = &znode->zbranch[0]; + + ubifs_assert(end > beg); + + while (end > beg) { + mid = (beg + end) >> 1; + cmp = keys_cmp(c, key, &zbr[mid].key); + if (cmp > 0) + beg = mid + 1; + else if (cmp < 0) + end = mid; + else { + *n = mid; + return 1; + } + } + + *n = end - 1; + + /* The insert point is after *n */ + ubifs_assert(*n >= -1 && *n < znode->child_cnt); + if (*n == -1) + ubifs_assert(keys_cmp(c, key, &zbr[0].key) < 0); + else + ubifs_assert(keys_cmp(c, key, &zbr[*n].key) > 0); + if (*n + 1 < znode->child_cnt) + ubifs_assert(keys_cmp(c, key, &zbr[*n + 1].key) < 0); + + return 0; +} + +/** + * ubifs_tnc_postorder_first - find first znode to do postorder tree traversal. + * @znode: znode to start at (root of the sub-tree to traverse) + * + * Find the lowest leftmost znode in a subtree of the TNC tree. The LNC is + * ignored. + */ +struct ubifs_znode *ubifs_tnc_postorder_first(struct ubifs_znode *znode) +{ + if (unlikely(!znode)) + return NULL; + + while (znode->level > 0) { + struct ubifs_znode *child; + + child = ubifs_tnc_find_child(znode, 0); + if (!child) + return znode; + znode = child; + } + + return znode; +} + +/** + * ubifs_tnc_postorder_next - next TNC tree element in postorder traversal. + * @znode: previous znode + * + * This function implements postorder TNC traversal. The LNC is ignored. + * Returns the next element or %NULL if @znode is already the last one. + */ +struct ubifs_znode *ubifs_tnc_postorder_next(struct ubifs_znode *znode) +{ + struct ubifs_znode *zn; + + ubifs_assert(znode); + if (unlikely(!znode->parent)) + return NULL; + + /* Switch to the next index in the parent */ + zn = ubifs_tnc_find_child(znode->parent, znode->iip + 1); + if (!zn) + /* This is in fact the last child, return parent */ + return znode->parent; + + /* Go to the first znode in this new subtree */ + return ubifs_tnc_postorder_first(zn); +} + +/** + * read_znode - read an indexing node from flash and fill znode. + * @c: UBIFS file-system description object + * @lnum: LEB of the indexing node to read + * @offs: node offset + * @len: node length + * @znode: znode to read to + * + * This function reads an indexing node from the flash media and fills znode + * with the read data. Returns zero in case of success and a negative error + * code in case of failure. The read indexing node is validated and if anything + * is wrong with it, this function prints complaint messages and returns + * %-EINVAL. + */ +static int read_znode(struct ubifs_info *c, int lnum, int offs, int len, + struct ubifs_znode *znode) +{ + int i, err, type, cmp; + struct ubifs_idx_node *idx; + + idx = kmalloc(c->max_idx_node_sz, GFP_NOFS); + if (!idx) + return -ENOMEM; + + err = ubifs_read_node(c, idx, UBIFS_IDX_NODE, len, lnum, offs); + if (err < 0) { + kfree(idx); + return err; + } + + znode->child_cnt = le16_to_cpu(idx->child_cnt); + znode->level = le16_to_cpu(idx->level); + + dbg_tnc("LEB %d:%d, level %d, %d branch", + lnum, offs, znode->level, znode->child_cnt); + + if (znode->child_cnt > c->fanout || znode->level > UBIFS_MAX_LEVELS) { + dbg_err("current fanout %d, branch count %d", + c->fanout, znode->child_cnt); + dbg_err("max levels %d, znode level %d", + UBIFS_MAX_LEVELS, znode->level); + err = 1; + goto out_dump; + } + + for (i = 0; i < znode->child_cnt; i++) { + const struct ubifs_branch *br = ubifs_idx_branch(c, idx, i); + struct ubifs_zbranch *zbr = &znode->zbranch[i]; + + key_read(c, &br->key, &zbr->key); + zbr->lnum = le32_to_cpu(br->lnum); + zbr->offs = le32_to_cpu(br->offs); + zbr->len = le32_to_cpu(br->len); + zbr->znode = NULL; + + /* Validate branch */ + + if (zbr->lnum < c->main_first || + zbr->lnum >= c->leb_cnt || zbr->offs < 0 || + zbr->offs + zbr->len > c->leb_size || zbr->offs & 7) { + dbg_err("bad branch %d", i); + err = 2; + goto out_dump; + } + + switch (key_type(c, &zbr->key)) { + case UBIFS_INO_KEY: + case UBIFS_DATA_KEY: + case UBIFS_DENT_KEY: + case UBIFS_XENT_KEY: + break; + default: + dbg_msg("bad key type at slot %d: %s", i, + DBGKEY(&zbr->key)); + err = 3; + goto out_dump; + } + + if (znode->level) + continue; + + type = key_type(c, &zbr->key); + if (c->ranges[type].max_len == 0) { + if (zbr->len != c->ranges[type].len) { + dbg_err("bad target node (type %d) length (%d)", + type, zbr->len); + dbg_err("have to be %d", c->ranges[type].len); + err = 4; + goto out_dump; + } + } else if (zbr->len < c->ranges[type].min_len || + zbr->len > c->ranges[type].max_len) { + dbg_err("bad target node (type %d) length (%d)", + type, zbr->len); + dbg_err("have to be in range of %d-%d", + c->ranges[type].min_len, + c->ranges[type].max_len); + err = 5; + goto out_dump; + } + } + + /* + * Ensure that the next key is greater or equivalent to the + * previous one. + */ + for (i = 0; i < znode->child_cnt - 1; i++) { + const union ubifs_key *key1, *key2; + + key1 = &znode->zbranch[i].key; + key2 = &znode->zbranch[i + 1].key; + + cmp = keys_cmp(c, key1, key2); + if (cmp > 0) { + dbg_err("bad key order (keys %d and %d)", i, i + 1); + err = 6; + goto out_dump; + } else if (cmp == 0 && !is_hash_key(c, key1)) { + /* These can only be keys with colliding hash */ + dbg_err("keys %d and %d are not hashed but equivalent", + i, i + 1); + err = 7; + goto out_dump; + } + } + + kfree(idx); + return 0; + +out_dump: + ubifs_err("bad indexing node at LEB %d:%d, error %d", lnum, offs, err); + dbg_dump_node(c, idx); + kfree(idx); + return -EINVAL; +} + +/** + * ubifs_load_znode - load znode to TNC cache. + * @c: UBIFS file-system description object + * @zbr: znode branch + * @parent: znode's parent + * @iip: index in parent + * + * This function loads znode pointed to by @zbr into the TNC cache and + * returns pointer to it in case of success and a negative error code in case + * of failure. + */ +struct ubifs_znode *ubifs_load_znode(struct ubifs_info *c, + struct ubifs_zbranch *zbr, + struct ubifs_znode *parent, int iip) +{ + int err; + struct ubifs_znode *znode; + + ubifs_assert(!zbr->znode); + /* + * A slab cache is not presently used for znodes because the znode size + * depends on the fanout which is stored in the superblock. + */ + znode = kzalloc(c->max_znode_sz, GFP_NOFS); + if (!znode) + return ERR_PTR(-ENOMEM); + + err = read_znode(c, zbr->lnum, zbr->offs, zbr->len, znode); + if (err) + goto out; + + zbr->znode = znode; + znode->parent = parent; + znode->time = get_seconds(); + znode->iip = iip; + + return znode; + +out: + kfree(znode); + return ERR_PTR(err); +} + +/** + * ubifs_tnc_read_node - read a leaf node from the flash media. + * @c: UBIFS file-system description object + * @zbr: key and position of the node + * @node: node is returned here + * + * This function reads a node defined by @zbr from the flash media. Returns + * zero in case of success or a negative negative error code in case of + * failure. + */ +int ubifs_tnc_read_node(struct ubifs_info *c, struct ubifs_zbranch *zbr, + void *node) +{ + union ubifs_key key1, *key = &zbr->key; + int err, type = key_type(c, key); + + err = ubifs_read_node(c, node, type, zbr->len, zbr->lnum, zbr->offs); + + if (err) { + dbg_tnc("key %s", DBGKEY(key)); + return err; + } + + /* Make sure the key of the read node is correct */ + key_read(c, node + UBIFS_KEY_OFFSET, &key1); + if (!keys_eq(c, key, &key1)) { + ubifs_err("bad key in node at LEB %d:%d", + zbr->lnum, zbr->offs); + dbg_tnc("looked for key %s found node's key %s", + DBGKEY(key), DBGKEY1(&key1)); + dbg_dump_node(c, node); + return -EINVAL; + } + + return 0; +} diff --git a/fs/ubifs/ubifs-media.h b/fs/ubifs/ubifs-media.h new file mode 100644 index 0000000..b25fc36 --- /dev/null +++ b/fs/ubifs/ubifs-media.h @@ -0,0 +1,751 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file describes UBIFS on-flash format and contains definitions of all the + * relevant data structures and constants. + * + * All UBIFS on-flash objects are stored in the form of nodes. All nodes start + * with the UBIFS node magic number and have the same common header. Nodes + * always sit at 8-byte aligned positions on the media and node header sizes are + * also 8-byte aligned (except for the indexing node and the padding node). + */ + +#ifndef __UBIFS_MEDIA_H__ +#define __UBIFS_MEDIA_H__ + +/* UBIFS node magic number (must not have the padding byte first or last) */ +#define UBIFS_NODE_MAGIC 0x06101831 + +/* UBIFS on-flash format version */ +#define UBIFS_FORMAT_VERSION 4 + +/* Minimum logical eraseblock size in bytes */ +#define UBIFS_MIN_LEB_SZ (15*1024) + +/* Initial CRC32 value used when calculating CRC checksums */ +#define UBIFS_CRC32_INIT 0xFFFFFFFFU + +/* + * UBIFS does not try to compress data if its length is less than the below + * constant. + */ +#define UBIFS_MIN_COMPR_LEN 128 + +/* + * If compressed data length is less than %UBIFS_MIN_COMPRESS_DIFF bytes + * shorter than uncompressed data length, UBIFS preferes to leave this data + * node uncompress, because it'll be read faster. + */ +#define UBIFS_MIN_COMPRESS_DIFF 64 + +/* Root inode number */ +#define UBIFS_ROOT_INO 1 + +/* Lowest inode number used for regular inodes (not UBIFS-only internal ones) */ +#define UBIFS_FIRST_INO 64 + +/* + * Maximum file name and extended attribute length (must be a multiple of 8, + * minus 1). + */ +#define UBIFS_MAX_NLEN 255 + +/* Maximum number of data journal heads */ +#define UBIFS_MAX_JHEADS 1 + +/* + * Size of UBIFS data block. Note, UBIFS is not a block oriented file-system, + * which means that it does not treat the underlying media as consisting of + * blocks like in case of hard drives. Do not be confused. UBIFS block is just + * the maximum amount of data which one data node can have or which can be + * attached to an inode node. + */ +#define UBIFS_BLOCK_SIZE 4096 +#define UBIFS_BLOCK_SHIFT 12 + +/* UBIFS padding byte pattern (must not be first or last byte of node magic) */ +#define UBIFS_PADDING_BYTE 0xCE + +/* Maximum possible key length */ +#define UBIFS_MAX_KEY_LEN 16 + +/* Key length ("simple" format) */ +#define UBIFS_SK_LEN 8 + +/* Minimum index tree fanout */ +#define UBIFS_MIN_FANOUT 3 + +/* Maximum number of levels in UBIFS indexing B-tree */ +#define UBIFS_MAX_LEVELS 512 + +/* Maximum amount of data attached to an inode in bytes */ +#define UBIFS_MAX_INO_DATA UBIFS_BLOCK_SIZE + +/* LEB Properties Tree fanout (must be power of 2) and fanout shift */ +#define UBIFS_LPT_FANOUT 4 +#define UBIFS_LPT_FANOUT_SHIFT 2 + +/* LEB Properties Tree bit field sizes */ +#define UBIFS_LPT_CRC_BITS 16 +#define UBIFS_LPT_CRC_BYTES 2 +#define UBIFS_LPT_TYPE_BITS 4 + +/* The key is always at the same position in all keyed nodes */ +#define UBIFS_KEY_OFFSET offsetof(struct ubifs_ino_node, key) + +/* + * LEB Properties Tree node types. + * + * UBIFS_LPT_PNODE: LPT leaf node (contains LEB properties) + * UBIFS_LPT_NNODE: LPT internal node + * UBIFS_LPT_LTAB: LPT's own lprops table + * UBIFS_LPT_LSAVE: LPT's save table (big model only) + * UBIFS_LPT_NODE_CNT: count of LPT node types + * UBIFS_LPT_NOT_A_NODE: all ones (15 for 4 bits) is never a valid node type + */ +enum { + UBIFS_LPT_PNODE, + UBIFS_LPT_NNODE, + UBIFS_LPT_LTAB, + UBIFS_LPT_LSAVE, + UBIFS_LPT_NODE_CNT, + UBIFS_LPT_NOT_A_NODE = (1 << UBIFS_LPT_TYPE_BITS) - 1, +}; + +/* + * UBIFS inode types. + * + * UBIFS_ITYPE_REG: regular file + * UBIFS_ITYPE_DIR: directory + * UBIFS_ITYPE_LNK: soft link + * UBIFS_ITYPE_BLK: block device node + * UBIFS_ITYPE_CHR: character device node + * UBIFS_ITYPE_FIFO: fifo + * UBIFS_ITYPE_SOCK: socket + * UBIFS_ITYPES_CNT: count of supported file types + */ +enum { + UBIFS_ITYPE_REG, + UBIFS_ITYPE_DIR, + UBIFS_ITYPE_LNK, + UBIFS_ITYPE_BLK, + UBIFS_ITYPE_CHR, + UBIFS_ITYPE_FIFO, + UBIFS_ITYPE_SOCK, + UBIFS_ITYPES_CNT, +}; + +/* + * Supported key hash functions. + * + * UBIFS_KEY_HASH_R5: R5 hash + * UBIFS_KEY_HASH_TEST: test hash which just returns first 4 bytes of the name + */ +enum { + UBIFS_KEY_HASH_R5, + UBIFS_KEY_HASH_TEST, +}; + +/* + * Supported key formats. + * + * UBIFS_SIMPLE_KEY_FMT: simple key format + */ +enum { + UBIFS_SIMPLE_KEY_FMT, +}; + +/* + * The simple key format uses 29 bits for storing UBIFS block number and hash + * value. + */ +#define UBIFS_S_KEY_BLOCK_BITS 29 +#define UBIFS_S_KEY_BLOCK_MASK 0x1FFFFFFF +#define UBIFS_S_KEY_HASH_BITS UBIFS_S_KEY_BLOCK_BITS +#define UBIFS_S_KEY_HASH_MASK UBIFS_S_KEY_BLOCK_MASK + +/* + * Key types. + * + * UBIFS_INO_KEY: inode node key + * UBIFS_DATA_KEY: data node key + * UBIFS_DENT_KEY: directory entry node key + * UBIFS_XENT_KEY: extended attribute entry key + * UBIFS_KEY_TYPES_CNT: number of supported key types + */ +enum { + UBIFS_INO_KEY, + UBIFS_DATA_KEY, + UBIFS_DENT_KEY, + UBIFS_XENT_KEY, + UBIFS_KEY_TYPES_CNT, +}; + +/* Count of LEBs reserved for the superblock area */ +#define UBIFS_SB_LEBS 1 +/* Count of LEBs reserved for the master area */ +#define UBIFS_MST_LEBS 2 + +/* First LEB of the superblock area */ +#define UBIFS_SB_LNUM 0 +/* First LEB of the master area */ +#define UBIFS_MST_LNUM (UBIFS_SB_LNUM + UBIFS_SB_LEBS) +/* First LEB of the log area */ +#define UBIFS_LOG_LNUM (UBIFS_MST_LNUM + UBIFS_MST_LEBS) + +/* + * The below constants define the absolute minimum values for various UBIFS + * media areas. Many of them actually depend of flash geometry and the FS + * configuration (number of journal heads, orphan LEBs, etc). This means that + * the smallest volume size which can be used for UBIFS cannot be pre-defined + * by these constants. The file-system that meets the below limitation will not + * necessarily mount. UBIFS does run-time calculations and validates the FS + * size. + */ + +/* Minimum number of logical eraseblocks in the log */ +#define UBIFS_MIN_LOG_LEBS 2 +/* Minimum number of bud logical eraseblocks (one for each head) */ +#define UBIFS_MIN_BUD_LEBS 3 +/* Minimum number of journal logical eraseblocks */ +#define UBIFS_MIN_JNL_LEBS (UBIFS_MIN_LOG_LEBS + UBIFS_MIN_BUD_LEBS) +/* Minimum number of LPT area logical eraseblocks */ +#define UBIFS_MIN_LPT_LEBS 2 +/* Minimum number of orphan area logical eraseblocks */ +#define UBIFS_MIN_ORPH_LEBS 1 +/* + * Minimum number of main area logical eraseblocks (buds, 3 for the index, 1 + * for GC, 1 for deletions, and at least 1 for committed data). + */ +#define UBIFS_MIN_MAIN_LEBS (UBIFS_MIN_BUD_LEBS + 6) + +/* Minimum number of logical eraseblocks */ +#define UBIFS_MIN_LEB_CNT (UBIFS_SB_LEBS + UBIFS_MST_LEBS + \ + UBIFS_MIN_LOG_LEBS + UBIFS_MIN_LPT_LEBS + \ + UBIFS_MIN_ORPH_LEBS + UBIFS_MIN_MAIN_LEBS) + +/* Node sizes (N.B. these are guaranteed to be multiples of 8) */ +#define UBIFS_CH_SZ sizeof(struct ubifs_ch) +#define UBIFS_INO_NODE_SZ sizeof(struct ubifs_ino_node) +#define UBIFS_DATA_NODE_SZ sizeof(struct ubifs_data_node) +#define UBIFS_DENT_NODE_SZ sizeof(struct ubifs_dent_node) +#define UBIFS_TRUN_NODE_SZ sizeof(struct ubifs_trun_node) +#define UBIFS_PAD_NODE_SZ sizeof(struct ubifs_pad_node) +#define UBIFS_SB_NODE_SZ sizeof(struct ubifs_sb_node) +#define UBIFS_MST_NODE_SZ sizeof(struct ubifs_mst_node) +#define UBIFS_REF_NODE_SZ sizeof(struct ubifs_ref_node) +#define UBIFS_IDX_NODE_SZ sizeof(struct ubifs_idx_node) +#define UBIFS_CS_NODE_SZ sizeof(struct ubifs_cs_node) +#define UBIFS_ORPH_NODE_SZ sizeof(struct ubifs_orph_node) +/* Extended attribute entry nodes are identical to directory entry nodes */ +#define UBIFS_XENT_NODE_SZ UBIFS_DENT_NODE_SZ +/* Only this does not have to be multiple of 8 bytes */ +#define UBIFS_BRANCH_SZ sizeof(struct ubifs_branch) + +/* Maximum node sizes (N.B. these are guaranteed to be multiples of 8) */ +#define UBIFS_MAX_DATA_NODE_SZ (UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE) +#define UBIFS_MAX_INO_NODE_SZ (UBIFS_INO_NODE_SZ + UBIFS_MAX_INO_DATA) +#define UBIFS_MAX_DENT_NODE_SZ (UBIFS_DENT_NODE_SZ + UBIFS_MAX_NLEN + 1) +#define UBIFS_MAX_XENT_NODE_SZ UBIFS_MAX_DENT_NODE_SZ + +/* The largest UBIFS node */ +#define UBIFS_MAX_NODE_SZ UBIFS_MAX_INO_NODE_SZ + +/* + * On-flash inode flags. + * + * UBIFS_COMPR_FL: use compression for this inode + * UBIFS_SYNC_FL: I/O on this inode has to be synchronous + * UBIFS_IMMUTABLE_FL: inode is immutable + * UBIFS_APPEND_FL: writes to the inode may only append data + * UBIFS_DIRSYNC_FL: I/O on this directory inode has to be synchronous + * UBIFS_XATTR_FL: this inode is the inode for an extended attribute value + * + * Note, these are on-flash flags which correspond to ioctl flags + * (@FS_COMPR_FL, etc). They have the same values now, but generally, do not + * have to be the same. + */ +enum { + UBIFS_COMPR_FL = 0x01, + UBIFS_SYNC_FL = 0x02, + UBIFS_IMMUTABLE_FL = 0x04, + UBIFS_APPEND_FL = 0x08, + UBIFS_DIRSYNC_FL = 0x10, + UBIFS_XATTR_FL = 0x20, +}; + +/* Inode flag bits used by UBIFS */ +#define UBIFS_FL_MASK 0x0000001F + +/* + * UBIFS compression algorithms. + * + * UBIFS_COMPR_NONE: no compression + * UBIFS_COMPR_LZO: LZO compression + * UBIFS_COMPR_ZLIB: ZLIB compression + * UBIFS_COMPR_TYPES_CNT: count of supported compression types + */ +enum { + UBIFS_COMPR_NONE, + UBIFS_COMPR_LZO, + UBIFS_COMPR_ZLIB, + UBIFS_COMPR_TYPES_CNT, +}; + +/* + * UBIFS node types. + * + * UBIFS_INO_NODE: inode node + * UBIFS_DATA_NODE: data node + * UBIFS_DENT_NODE: directory entry node + * UBIFS_XENT_NODE: extended attribute node + * UBIFS_TRUN_NODE: truncation node + * UBIFS_PAD_NODE: padding node + * UBIFS_SB_NODE: superblock node + * UBIFS_MST_NODE: master node + * UBIFS_REF_NODE: LEB reference node + * UBIFS_IDX_NODE: index node + * UBIFS_CS_NODE: commit start node + * UBIFS_ORPH_NODE: orphan node + * UBIFS_NODE_TYPES_CNT: count of supported node types + * + * Note, we index arrays by these numbers, so keep them low and contiguous. + * Node type constants for inodes, direntries and so on have to be the same as + * corresponding key type constants. + */ +enum { + UBIFS_INO_NODE, + UBIFS_DATA_NODE, + UBIFS_DENT_NODE, + UBIFS_XENT_NODE, + UBIFS_TRUN_NODE, + UBIFS_PAD_NODE, + UBIFS_SB_NODE, + UBIFS_MST_NODE, + UBIFS_REF_NODE, + UBIFS_IDX_NODE, + UBIFS_CS_NODE, + UBIFS_ORPH_NODE, + UBIFS_NODE_TYPES_CNT, +}; + +/* + * Master node flags. + * + * UBIFS_MST_DIRTY: rebooted uncleanly - master node is dirty + * UBIFS_MST_NO_ORPHS: no orphan inodes present + * UBIFS_MST_RCVRY: written by recovery + */ +enum { + UBIFS_MST_DIRTY = 1, + UBIFS_MST_NO_ORPHS = 2, + UBIFS_MST_RCVRY = 4, +}; + +/* + * Node group type (used by recovery to recover whole group or none). + * + * UBIFS_NO_NODE_GROUP: this node is not part of a group + * UBIFS_IN_NODE_GROUP: this node is a part of a group + * UBIFS_LAST_OF_NODE_GROUP: this node is the last in a group + */ +enum { + UBIFS_NO_NODE_GROUP = 0, + UBIFS_IN_NODE_GROUP, + UBIFS_LAST_OF_NODE_GROUP, +}; + +/* + * Superblock flags. + * + * UBIFS_FLG_BIGLPT: if "big" LPT model is used if set + */ +enum { + UBIFS_FLG_BIGLPT = 0x02, +}; + +/** + * struct ubifs_ch - common header node. + * @magic: UBIFS node magic number (%UBIFS_NODE_MAGIC) + * @crc: CRC-32 checksum of the node header + * @sqnum: sequence number + * @len: full node length + * @node_type: node type + * @group_type: node group type + * @padding: reserved for future, zeroes + * + * Every UBIFS node starts with this common part. If the node has a key, the + * key always goes next. + */ +struct ubifs_ch { + __le32 magic; + __le32 crc; + __le64 sqnum; + __le32 len; + __u8 node_type; + __u8 group_type; + __u8 padding[2]; +} __attribute__ ((packed)); + +/** + * union ubifs_dev_desc - device node descriptor. + * @new: new type device descriptor + * @huge: huge type device descriptor + * + * This data structure describes major/minor numbers of a device node. In an + * inode is a device node then its data contains an object of this type. UBIFS + * uses standard Linux "new" and "huge" device node encodings. + */ +union ubifs_dev_desc { + __le32 new; + __le64 huge; +} __attribute__ ((packed)); + +/** + * struct ubifs_ino_node - inode node. + * @ch: common header + * @key: node key + * @creat_sqnum: sequence number at time of creation + * @size: inode size in bytes (amount of uncompressed data) + * @atime_sec: access time seconds + * @ctime_sec: creation time seconds + * @mtime_sec: modification time seconds + * @atime_nsec: access time nanoseconds + * @ctime_nsec: creation time nanoseconds + * @mtime_nsec: modification time nanoseconds + * @nlink: number of hard links + * @uid: owner ID + * @gid: group ID + * @mode: access flags + * @flags: per-inode flags (%UBIFS_COMPR_FL, %UBIFS_SYNC_FL, etc) + * @data_len: inode data length + * @xattr_cnt: count of extended attributes this inode has + * @xattr_size: summarized size of all extended attributes in bytes + * @padding1: reserved for future, zeroes + * @xattr_names: sum of lengths of all extended attribute names belonging to + * this inode + * @compr_type: compression type used for this inode + * @padding2: reserved for future, zeroes + * @data: data attached to the inode + * + * Note, even though inode compression type is defined by @compr_type, some + * nodes of this inode may be compressed with different compressor - this + * happens if compression type is changed while the inode already has data + * nodes. But @compr_type will be use for further writes to the inode. + * + * Note, do not forget to amend 'zero_ino_node_unused()' function when changing + * the padding fields. + */ +struct ubifs_ino_node { + struct ubifs_ch ch; + __u8 key[UBIFS_MAX_KEY_LEN]; + __le64 creat_sqnum; + __le64 size; + __le64 atime_sec; + __le64 ctime_sec; + __le64 mtime_sec; + __le32 atime_nsec; + __le32 ctime_nsec; + __le32 mtime_nsec; + __le32 nlink; + __le32 uid; + __le32 gid; + __le32 mode; + __le32 flags; + __le32 data_len; + __le32 xattr_cnt; + __le32 xattr_size; + __u8 padding1[4]; /* Watch 'zero_ino_node_unused()' if changing! */ + __le32 xattr_names; + __le16 compr_type; + __u8 padding2[26]; /* Watch 'zero_ino_node_unused()' if changing! */ + __u8 data[]; +} __attribute__ ((packed)); + +/** + * struct ubifs_dent_node - directory entry node. + * @ch: common header + * @key: node key + * @inum: target inode number + * @padding1: reserved for future, zeroes + * @type: type of the target inode (%UBIFS_ITYPE_REG, %UBIFS_ITYPE_DIR, etc) + * @nlen: name length + * @padding2: reserved for future, zeroes + * @name: zero-terminated name + * + * Note, do not forget to amend 'zero_dent_node_unused()' function when + * changing the padding fields. + */ +struct ubifs_dent_node { + struct ubifs_ch ch; + __u8 key[UBIFS_MAX_KEY_LEN]; + __le64 inum; + __u8 padding1; + __u8 type; + __le16 nlen; + __u8 padding2[4]; /* Watch 'zero_dent_node_unused()' if changing! */ + __u8 name[]; +} __attribute__ ((packed)); + +/** + * struct ubifs_data_node - data node. + * @ch: common header + * @key: node key + * @size: uncompressed data size in bytes + * @compr_type: compression type (%UBIFS_COMPR_NONE, %UBIFS_COMPR_LZO, etc) + * @padding: reserved for future, zeroes + * @data: data + * + * Note, do not forget to amend 'zero_data_node_unused()' function when + * changing the padding fields. + */ +struct ubifs_data_node { + struct ubifs_ch ch; + __u8 key[UBIFS_MAX_KEY_LEN]; + __le32 size; + __le16 compr_type; + __u8 padding[2]; /* Watch 'zero_data_node_unused()' if changing! */ + __u8 data[]; +} __attribute__ ((packed)); + +/** + * struct ubifs_trun_node - truncation node. + * @ch: common header + * @inum: truncated inode number + * @padding: reserved for future, zeroes + * @old_size: size before truncation + * @new_size: size after truncation + * + * This node exists only in the journal and never goes to the main area. Note, + * do not forget to amend 'zero_trun_node_unused()' function when changing the + * padding fields. + */ +struct ubifs_trun_node { + struct ubifs_ch ch; + __le32 inum; + __u8 padding[12]; /* Watch 'zero_trun_node_unused()' if changing! */ + __le64 old_size; + __le64 new_size; +} __attribute__ ((packed)); + +/** + * struct ubifs_pad_node - padding node. + * @ch: common header + * @pad_len: how many bytes after this node are unused (because padded) + * @padding: reserved for future, zeroes + */ +struct ubifs_pad_node { + struct ubifs_ch ch; + __le32 pad_len; +} __attribute__ ((packed)); + +/** + * struct ubifs_sb_node - superblock node. + * @ch: common header + * @padding: reserved for future, zeroes + * @key_hash: type of hash function used in keys + * @key_fmt: format of the key + * @flags: file-system flags (%UBIFS_FLG_BIGLPT, etc) + * @min_io_size: minimal input/output unit size + * @leb_size: logical eraseblock size in bytes + * @leb_cnt: count of LEBs used by file-system + * @max_leb_cnt: maximum count of LEBs used by file-system + * @max_bud_bytes: maximum amount of data stored in buds + * @log_lebs: log size in logical eraseblocks + * @lpt_lebs: number of LEBs used for lprops table + * @orph_lebs: number of LEBs used for recording orphans + * @jhead_cnt: count of journal heads + * @fanout: tree fanout (max. number of links per indexing node) + * @lsave_cnt: number of LEB numbers in LPT's save table + * @fmt_version: UBIFS on-flash format version + * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc) + * @padding1: reserved for future, zeroes + * @rp_uid: reserve pool UID + * @rp_gid: reserve pool GID + * @rp_size: size of the reserved pool in bytes + * @padding2: reserved for future, zeroes + * @time_gran: time granularity in nanoseconds + * @uuid: UUID generated when the file system image was created + */ +struct ubifs_sb_node { + struct ubifs_ch ch; + __u8 padding[2]; + __u8 key_hash; + __u8 key_fmt; + __le32 flags; + __le32 min_io_size; + __le32 leb_size; + __le32 leb_cnt; + __le32 max_leb_cnt; + __le64 max_bud_bytes; + __le32 log_lebs; + __le32 lpt_lebs; + __le32 orph_lebs; + __le32 jhead_cnt; + __le32 fanout; + __le32 lsave_cnt; + __le32 fmt_version; + __le16 default_compr; + __u8 padding1[2]; + __le32 rp_uid; + __le32 rp_gid; + __le64 rp_size; + __le32 time_gran; + __u8 uuid[16]; + __u8 padding2[3972]; +} __attribute__ ((packed)); + +/** + * struct ubifs_mst_node - master node. + * @ch: common header + * @highest_inum: highest inode number in the committed index + * @cmt_no: commit number + * @flags: various flags (%UBIFS_MST_DIRTY, etc) + * @log_lnum: start of the log + * @root_lnum: LEB number of the root indexing node + * @root_offs: offset within @root_lnum + * @root_len: root indexing node length + * @gc_lnum: LEB reserved for garbage collection (%-1 value means the LEB was + * not reserved and should be reserved on mount) + * @ihead_lnum: LEB number of index head + * @ihead_offs: offset of index head + * @index_size: size of index on flash + * @total_free: total free space in bytes + * @total_dirty: total dirty space in bytes + * @total_used: total used space in bytes (includes only data LEBs) + * @total_dead: total dead space in bytes (includes only data LEBs) + * @total_dark: total dark space in bytes (includes only data LEBs) + * @lpt_lnum: LEB number of LPT root nnode + * @lpt_offs: offset of LPT root nnode + * @nhead_lnum: LEB number of LPT head + * @nhead_offs: offset of LPT head + * @ltab_lnum: LEB number of LPT's own lprops table + * @ltab_offs: offset of LPT's own lprops table + * @lsave_lnum: LEB number of LPT's save table (big model only) + * @lsave_offs: offset of LPT's save table (big model only) + * @lscan_lnum: LEB number of last LPT scan + * @empty_lebs: number of empty logical eraseblocks + * @idx_lebs: number of indexing logical eraseblocks + * @leb_cnt: count of LEBs used by file-system + * @padding: reserved for future, zeroes + */ +struct ubifs_mst_node { + struct ubifs_ch ch; + __le64 highest_inum; + __le64 cmt_no; + __le32 flags; + __le32 log_lnum; + __le32 root_lnum; + __le32 root_offs; + __le32 root_len; + __le32 gc_lnum; + __le32 ihead_lnum; + __le32 ihead_offs; + __le64 index_size; + __le64 total_free; + __le64 total_dirty; + __le64 total_used; + __le64 total_dead; + __le64 total_dark; + __le32 lpt_lnum; + __le32 lpt_offs; + __le32 nhead_lnum; + __le32 nhead_offs; + __le32 ltab_lnum; + __le32 ltab_offs; + __le32 lsave_lnum; + __le32 lsave_offs; + __le32 lscan_lnum; + __le32 empty_lebs; + __le32 idx_lebs; + __le32 leb_cnt; + __u8 padding[344]; +} __attribute__ ((packed)); + +/** + * struct ubifs_ref_node - logical eraseblock reference node. + * @ch: common header + * @lnum: the referred logical eraseblock number + * @offs: start offset in the referred LEB + * @jhead: journal head number + * @padding: reserved for future, zeroes + */ +struct ubifs_ref_node { + struct ubifs_ch ch; + __le32 lnum; + __le32 offs; + __le32 jhead; + __u8 padding[28]; +} __attribute__ ((packed)); + +/** + * struct ubifs_branch - key/reference/length branch + * @lnum: LEB number of the target node + * @offs: offset within @lnum + * @len: target node length + * @key: key + */ +struct ubifs_branch { + __le32 lnum; + __le32 offs; + __le32 len; + __u8 key[]; +} __attribute__ ((packed)); + +/** + * struct ubifs_idx_node - indexing node. + * @ch: common header + * @child_cnt: number of child index nodes + * @level: tree level + * @branches: LEB number / offset / length / key branches + */ +struct ubifs_idx_node { + struct ubifs_ch ch; + __le16 child_cnt; + __le16 level; + __u8 branches[]; +} __attribute__ ((packed)); + +/** + * struct ubifs_cs_node - commit start node. + * @ch: common header + * @cmt_no: commit number + */ +struct ubifs_cs_node { + struct ubifs_ch ch; + __le64 cmt_no; +} __attribute__ ((packed)); + +/** + * struct ubifs_orph_node - orphan node. + * @ch: common header + * @cmt_no: commit number (also top bit is set on the last node of the commit) + * @inos: inode numbers of orphans + */ +struct ubifs_orph_node { + struct ubifs_ch ch; + __le64 cmt_no; + __le64 inos[]; +} __attribute__ ((packed)); + +#endif /* __UBIFS_MEDIA_H__ */ diff --git a/fs/ubifs/ubifs.c b/fs/ubifs/ubifs.c new file mode 100644 index 0000000..32f9ff8 --- /dev/null +++ b/fs/ubifs/ubifs.c @@ -0,0 +1,687 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * (C) Copyright 2008-2009 + * Stefan Roese, DENX Software Engineering, sr@denx.de. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +#include "ubifs.h" + +#if !defined(CONFIG_SYS_64BIT_VSPRINTF) +#warning Please define CONFIG_SYS_64BIT_VSPRINTF for correct output! +#endif + +DECLARE_GLOBAL_DATA_PTR; + +/* compress.c */ + +/* + * We need a wrapper for gunzip() because the parameters are + * incompatible with the lzo decompressor. + */ +static int gzip_decompress(const unsigned char *in, size_t in_len, + unsigned char *out, size_t *out_len) +{ + unsigned long len = in_len; + return gunzip(out, *out_len, (unsigned char *)in, &len); +} + +/* Fake description object for the "none" compressor */ +static struct ubifs_compressor none_compr = { + .compr_type = UBIFS_COMPR_NONE, + .name = "no compression", + .capi_name = "", + .decompress = NULL, +}; + +static struct ubifs_compressor lzo_compr = { + .compr_type = UBIFS_COMPR_LZO, + .name = "LZO", + .capi_name = "lzo", + .decompress = lzo1x_decompress_safe, +}; + +static struct ubifs_compressor zlib_compr = { + .compr_type = UBIFS_COMPR_ZLIB, + .name = "zlib", + .capi_name = "deflate", + .decompress = gzip_decompress, +}; + +/* All UBIFS compressors */ +struct ubifs_compressor *ubifs_compressors[UBIFS_COMPR_TYPES_CNT]; + +/** + * ubifs_decompress - decompress data. + * @in_buf: data to decompress + * @in_len: length of the data to decompress + * @out_buf: output buffer where decompressed data should + * @out_len: output length is returned here + * @compr_type: type of compression + * + * This function decompresses data from buffer @in_buf into buffer @out_buf. + * The length of the uncompressed data is returned in @out_len. This functions + * returns %0 on success or a negative error code on failure. + */ +int ubifs_decompress(const void *in_buf, int in_len, void *out_buf, + int *out_len, int compr_type) +{ + int err; + struct ubifs_compressor *compr; + + if (unlikely(compr_type < 0 || compr_type >= UBIFS_COMPR_TYPES_CNT)) { + ubifs_err("invalid compression type %d", compr_type); + return -EINVAL; + } + + compr = ubifs_compressors[compr_type]; + + if (unlikely(!compr->capi_name)) { + ubifs_err("%s compression is not compiled in", compr->name); + return -EINVAL; + } + + if (compr_type == UBIFS_COMPR_NONE) { + memcpy(out_buf, in_buf, in_len); + *out_len = in_len; + return 0; + } + + err = compr->decompress(in_buf, in_len, out_buf, (size_t *)out_len); + if (err) + ubifs_err("cannot decompress %d bytes, compressor %s, " + "error %d", in_len, compr->name, err); + + return err; +} + +/** + * compr_init - initialize a compressor. + * @compr: compressor description object + * + * This function initializes the requested compressor and returns zero in case + * of success or a negative error code in case of failure. + */ +static int __init compr_init(struct ubifs_compressor *compr) +{ + ubifs_compressors[compr->compr_type] = compr; + ubifs_compressors[compr->compr_type]->name += gd->reloc_off; + ubifs_compressors[compr->compr_type]->capi_name += gd->reloc_off; + ubifs_compressors[compr->compr_type]->decompress += gd->reloc_off; + return 0; +} + +/** + * ubifs_compressors_init - initialize UBIFS compressors. + * + * This function initializes the compressor which were compiled in. Returns + * zero in case of success and a negative error code in case of failure. + */ +int __init ubifs_compressors_init(void) +{ + int err; + + err = compr_init(&lzo_compr); + if (err) + return err; + + err = compr_init(&zlib_compr); + if (err) + return err; + + err = compr_init(&none_compr); + if (err) + return err; + + return 0; +} + +/* + * ubifsls... + */ + +static int filldir(struct ubifs_info *c, const char *name, int namlen, + u64 ino, unsigned int d_type) +{ + struct inode *inode; + char filetime[32]; + + switch (d_type) { + case UBIFS_ITYPE_REG: + printf("\t"); + break; + case UBIFS_ITYPE_DIR: + printf("<DIR>\t"); + break; + case UBIFS_ITYPE_LNK: + printf("<LNK>\t"); + break; + default: + printf("other\t"); + break; + } + + inode = ubifs_iget(c->vfs_sb, ino); + if (IS_ERR(inode)) { + printf("%s: Error in ubifs_iget(), ino=%lld ret=%p!\n", + __func__, ino, inode); + return -1; + } + ctime_r((time_t *)&inode->i_mtime, filetime); + printf("%9lld %24.24s ", inode->i_size, filetime); + ubifs_iput(inode); + + printf("%s\n", name); + + return 0; +} + +static int ubifs_printdir(struct file *file, void *dirent) +{ + int err, over = 0; + struct qstr nm; + union ubifs_key key; + struct ubifs_dent_node *dent; + struct inode *dir = file->f_path.dentry->d_inode; + struct ubifs_info *c = dir->i_sb->s_fs_info; + + dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, file->f_pos); + + if (file->f_pos > UBIFS_S_KEY_HASH_MASK || file->f_pos == 2) + /* + * The directory was seek'ed to a senseless position or there + * are no more entries. + */ + return 0; + + if (file->f_pos == 1) { + /* Find the first entry in TNC and save it */ + lowest_dent_key(c, &key, dir->i_ino); + nm.name = NULL; + dent = ubifs_tnc_next_ent(c, &key, &nm); + if (IS_ERR(dent)) { + err = PTR_ERR(dent); + goto out; + } + + file->f_pos = key_hash_flash(c, &dent->key); + file->private_data = dent; + } + + dent = file->private_data; + if (!dent) { + /* + * The directory was seek'ed to and is now readdir'ed. + * Find the entry corresponding to @file->f_pos or the + * closest one. + */ + dent_key_init_hash(c, &key, dir->i_ino, file->f_pos); + nm.name = NULL; + dent = ubifs_tnc_next_ent(c, &key, &nm); + if (IS_ERR(dent)) { + err = PTR_ERR(dent); + goto out; + } + file->f_pos = key_hash_flash(c, &dent->key); + file->private_data = dent; + } + + while (1) { + dbg_gen("feed '%s', ino %llu, new f_pos %#x", + dent->name, (unsigned long long)le64_to_cpu(dent->inum), + key_hash_flash(c, &dent->key)); + ubifs_assert(le64_to_cpu(dent->ch.sqnum) > ubifs_inode(dir)->creat_sqnum); + + nm.len = le16_to_cpu(dent->nlen); + over = filldir(c, (char *)dent->name, nm.len, + le64_to_cpu(dent->inum), dent->type); + if (over) + return 0; + + /* Switch to the next entry */ + key_read(c, &dent->key, &key); + nm.name = (char *)dent->name; + dent = ubifs_tnc_next_ent(c, &key, &nm); + if (IS_ERR(dent)) { + err = PTR_ERR(dent); + goto out; + } + + kfree(file->private_data); + file->f_pos = key_hash_flash(c, &dent->key); + file->private_data = dent; + cond_resched(); + } + +out: + if (err != -ENOENT) { + ubifs_err("cannot find next direntry, error %d", err); + return err; + } + + kfree(file->private_data); + file->private_data = NULL; + file->f_pos = 2; + return 0; +} + +static int ubifs_finddir(struct super_block *sb, char *dirname, + unsigned long root_inum, unsigned long *inum) +{ + int err; + struct qstr nm; + union ubifs_key key; + struct ubifs_dent_node *dent; + struct ubifs_info *c; + struct file *file; + struct dentry *dentry; + struct inode *dir; + + file = kzalloc(sizeof(struct file), 0); + dentry = kzalloc(sizeof(struct dentry), 0); + dir = kzalloc(sizeof(struct inode), 0); + if (!file || !dentry || !dir) { + printf("%s: Error, no memory for malloc!\n", __func__); + err = -ENOMEM; + goto out; + } + + dir->i_sb = sb; + file->f_path.dentry = dentry; + file->f_path.dentry->d_parent = dentry; + file->f_path.dentry->d_inode = dir; + file->f_path.dentry->d_inode->i_ino = root_inum; + c = sb->s_fs_info; + + dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, file->f_pos); + + /* Find the first entry in TNC and save it */ + lowest_dent_key(c, &key, dir->i_ino); + nm.name = NULL; + dent = ubifs_tnc_next_ent(c, &key, &nm); + if (IS_ERR(dent)) { + err = PTR_ERR(dent); + goto out; + } + + file->f_pos = key_hash_flash(c, &dent->key); + file->private_data = dent; + + while (1) { + dbg_gen("feed '%s', ino %llu, new f_pos %#x", + dent->name, (unsigned long long)le64_to_cpu(dent->inum), + key_hash_flash(c, &dent->key)); + ubifs_assert(le64_to_cpu(dent->ch.sqnum) > ubifs_inode(dir)->creat_sqnum); + + nm.len = le16_to_cpu(dent->nlen); + if ((strncmp(dirname, (char *)dent->name, nm.len) == 0) && + (strlen(dirname) == nm.len)) { + *inum = le64_to_cpu(dent->inum); + return 1; + } + + /* Switch to the next entry */ + key_read(c, &dent->key, &key); + nm.name = (char *)dent->name; + dent = ubifs_tnc_next_ent(c, &key, &nm); + if (IS_ERR(dent)) { + err = PTR_ERR(dent); + goto out; + } + + kfree(file->private_data); + file->f_pos = key_hash_flash(c, &dent->key); + file->private_data = dent; + cond_resched(); + } + +out: + if (err != -ENOENT) { + ubifs_err("cannot find next direntry, error %d", err); + return err; + } + + if (file) + free(file); + if (dentry) + free(dentry); + if (dir) + free(dir); + + if (file->private_data) + kfree(file->private_data); + file->private_data = NULL; + file->f_pos = 2; + return 0; +} + +static unsigned long ubifs_findfile(struct super_block *sb, char *filename) +{ + int ret; + char *next; + char fpath[128]; + char *name = fpath; + unsigned long root_inum = 1; + unsigned long inum; + + strcpy(fpath, filename); + + /* Remove all leading slashes */ + while (*name == '/') + name++; + + /* + * Handle root-direcoty ('/') + */ + inum = root_inum; + if (!name || *name == '\0') + return inum; + + for (;;) { + /* Extract the actual part from the pathname. */ + next = strchr(name, '/'); + if (next) { + /* Remove all leading slashes. */ + while (*next == '/') + *(next++) = '\0'; + } + + ret = ubifs_finddir(sb, name, root_inum, &inum); + + /* + * Check if directory with this name exists + */ + + /* Found the node! */ + if (!next || *next == '\0') { + if (ret) + return inum; + + break; + } + + root_inum = inum; + name = next; + } + + return 0; +} + +int ubifs_ls(char *filename) +{ + struct ubifs_info *c = ubifs_sb->s_fs_info; + struct file *file; + struct dentry *dentry; + struct inode *dir; + void *dirent = NULL; + unsigned long inum; + int ret = 0; + + c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READONLY); + inum = ubifs_findfile(ubifs_sb, filename); + if (!inum) { + ret = -1; + goto out; + } + + file = kzalloc(sizeof(struct file), 0); + dentry = kzalloc(sizeof(struct dentry), 0); + dir = kzalloc(sizeof(struct inode), 0); + if (!file || !dentry || !dir) { + printf("%s: Error, no memory for malloc!\n", __func__); + ret = -ENOMEM; + goto out_mem; + } + + dir->i_sb = ubifs_sb; + file->f_path.dentry = dentry; + file->f_path.dentry->d_parent = dentry; + file->f_path.dentry->d_inode = dir; + file->f_path.dentry->d_inode->i_ino = inum; + file->f_pos = 1; + file->private_data = NULL; + ubifs_printdir(file, dirent); + +out_mem: + if (file) + free(file); + if (dentry) + free(dentry); + if (dir) + free(dir); + +out: + ubi_close_volume(c->ubi); + return ret; +} + +/* + * ubifsload... + */ + +/* file.c */ + +static inline void *kmap(struct page *page) +{ + return page->addr; +} + +static int read_block(struct inode *inode, void *addr, unsigned int block, + struct ubifs_data_node *dn) +{ + struct ubifs_info *c = inode->i_sb->s_fs_info; + int err, len, out_len; + union ubifs_key key; + unsigned int dlen; + + data_key_init(c, &key, inode->i_ino, block); + err = ubifs_tnc_lookup(c, &key, dn); + if (err) { + if (err == -ENOENT) + /* Not found, so it must be a hole */ + memset(addr, 0, UBIFS_BLOCK_SIZE); + return err; + } + + ubifs_assert(le64_to_cpu(dn->ch.sqnum) > ubifs_inode(inode)->creat_sqnum); + + len = le32_to_cpu(dn->size); + if (len <= 0 || len > UBIFS_BLOCK_SIZE) + goto dump; + + dlen = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ; + out_len = UBIFS_BLOCK_SIZE; + err = ubifs_decompress(&dn->data, dlen, addr, &out_len, + le16_to_cpu(dn->compr_type)); + if (err || len != out_len) + goto dump; + + /* + * Data length can be less than a full block, even for blocks that are + * not the last in the file (e.g., as a result of making a hole and + * appending data). Ensure that the remainder is zeroed out. + */ + if (len < UBIFS_BLOCK_SIZE) + memset(addr + len, 0, UBIFS_BLOCK_SIZE - len); + + return 0; + +dump: + ubifs_err("bad data node (block %u, inode %lu)", + block, inode->i_ino); + dbg_dump_node(c, dn); + return -EINVAL; +} + +static int do_readpage(struct ubifs_info *c, struct inode *inode, struct page *page) +{ + void *addr; + int err = 0, i; + unsigned int block, beyond; + struct ubifs_data_node *dn; + loff_t i_size = inode->i_size; + + dbg_gen("ino %lu, pg %lu, i_size %lld", + inode->i_ino, page->index, i_size); + + addr = kmap(page); + + block = page->index << UBIFS_BLOCKS_PER_PAGE_SHIFT; + beyond = (i_size + UBIFS_BLOCK_SIZE - 1) >> UBIFS_BLOCK_SHIFT; + if (block >= beyond) { + /* Reading beyond inode */ + memset(addr, 0, PAGE_CACHE_SIZE); + goto out; + } + + dn = kmalloc(UBIFS_MAX_DATA_NODE_SZ, GFP_NOFS); + if (!dn) { + err = -ENOMEM; + goto error; + } + + i = 0; + while (1) { + int ret; + + if (block >= beyond) { + /* Reading beyond inode */ + err = -ENOENT; + memset(addr, 0, UBIFS_BLOCK_SIZE); + } else { + ret = read_block(inode, addr, block, dn); + if (ret) { + err = ret; + if (err != -ENOENT) + break; + } else if (block + 1 == beyond) { + int dlen = le32_to_cpu(dn->size); + int ilen = i_size & (UBIFS_BLOCK_SIZE - 1); + + if (ilen && ilen < dlen) + memset(addr + ilen, 0, dlen - ilen); + } + } + if (++i >= UBIFS_BLOCKS_PER_PAGE) + break; + block += 1; + addr += UBIFS_BLOCK_SIZE; + } + if (err) { + if (err == -ENOENT) { + /* Not found, so it must be a hole */ + dbg_gen("hole"); + goto out_free; + } + ubifs_err("cannot read page %lu of inode %lu, error %d", + page->index, inode->i_ino, err); + goto error; + } + +out_free: + kfree(dn); +out: + return 0; + +error: + kfree(dn); + return err; +} + +int ubifs_load(char *filename, u32 addr, u32 size) +{ + struct ubifs_info *c = ubifs_sb->s_fs_info; + unsigned long inum; + struct inode *inode; + struct page page; + int err = 0; + int i; + int count; + char link_name[64]; + struct ubifs_inode *ui; + + c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READONLY); + inum = ubifs_findfile(ubifs_sb, filename); + if (!inum) { + err = -1; + goto out; + } + + /* + * Read file inode + */ + inode = ubifs_iget(ubifs_sb, inum); + if (IS_ERR(inode)) { + printf("%s: Error reading inode %ld!\n", __func__, inum); + err = PTR_ERR(inode); + goto out; + } + + /* + * Check for symbolic link + */ + ui = ubifs_inode(inode); + if (((inode->i_mode & S_IFMT) == S_IFLNK) && ui->data_len) { + memcpy(link_name, ui->data, ui->data_len); + printf("%s is linked to %s!\n", filename, link_name); + ubifs_iput(inode); + + /* + * Now we have the "real" filename, call ubifs_load() + * again (recursive call) to load this file instead + */ + return ubifs_load(link_name, addr, size); + } + + /* + * If no size was specified or if size bigger than filesize + * set size to filesize + */ + if ((size == 0) || (size > inode->i_size)) + size = inode->i_size; + + count = (size + UBIFS_BLOCK_SIZE - 1) >> UBIFS_BLOCK_SHIFT; + printf("Loading file '%s' to addr 0x%08x with size %d (0x%08x)...\n", + filename, addr, size, size); + + page.addr = (void *)addr; + page.index = 0; + page.inode = inode; + for (i = 0; i < count; i++) { + err = do_readpage(c, inode, &page); + if (err) + break; + + page.addr += PAGE_SIZE; + page.index++; + } + + if (err) + printf("Error reading file '%s'\n", filename); + else + printf("Done\n"); + + ubifs_iput(inode); + +out: + ubi_close_volume(c->ubi); + return err; +} diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h new file mode 100644 index 0000000..f342dd8 --- /dev/null +++ b/fs/ubifs/ubifs.h @@ -0,0 +1,2173 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation + * + * (C) Copyright 2008-2009 + * Stefan Roese, DENX Software Engineering, sr@denx.de. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +#ifndef __UBIFS_H__ +#define __UBIFS_H__ + +#if 0 /* Enable for debugging output */ +#define CONFIG_UBIFS_FS_DEBUG +#define CONFIG_UBIFS_FS_DEBUG_MSG_LVL 3 +#endif + +#include <ubi_uboot.h> +#include <linux/ctype.h> +#include <linux/time.h> +#include <linux/math64.h> +#include "ubifs-media.h" + +struct dentry; +struct file; +struct iattr; +struct kstat; +struct vfsmount; + +extern struct super_block *ubifs_sb; + +extern unsigned int ubifs_msg_flags; +extern unsigned int ubifs_chk_flags; +extern unsigned int ubifs_tst_flags; + +#define pgoff_t unsigned long + +/* + * We "simulate" the Linux page struct much simpler here + */ +struct page { + pgoff_t index; + void *addr; + struct inode *inode; +}; + +void iput(struct inode *inode); + +/* + * The atomic operations are used for budgeting etc which is not + * needed for the read-only U-Boot implementation: + */ +#define atomic_long_inc(a) +#define atomic_long_dec(a) +#define atomic_long_sub(a, b) + +/* linux/include/time.h */ + +struct timespec { + time_t tv_sec; /* seconds */ + long tv_nsec; /* nanoseconds */ +}; + +/* linux/include/dcache.h */ + +/* + * "quick string" -- eases parameter passing, but more importantly + * saves "metadata" about the string (ie length and the hash). + * + * hash comes first so it snuggles against d_parent in the + * dentry. + */ +struct qstr { + unsigned int hash; + unsigned int len; + const char *name; +}; + +struct inode { + struct hlist_node i_hash; + struct list_head i_list; + struct list_head i_sb_list; + struct list_head i_dentry; + unsigned long i_ino; + unsigned int i_nlink; + uid_t i_uid; + gid_t i_gid; + dev_t i_rdev; + u64 i_version; + loff_t i_size; +#ifdef __NEED_I_SIZE_ORDERED + seqcount_t i_size_seqcount; +#endif + struct timespec i_atime; + struct timespec i_mtime; + struct timespec i_ctime; + unsigned int i_blkbits; + unsigned short i_bytes; + umode_t i_mode; + spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */ + struct mutex i_mutex; + struct rw_semaphore i_alloc_sem; + const struct inode_operations *i_op; + const struct file_operations *i_fop; /* former ->i_op->default_file_ops */ + struct super_block *i_sb; + struct file_lock *i_flock; +#ifdef CONFIG_QUOTA + struct dquot *i_dquot[MAXQUOTAS]; +#endif + struct list_head i_devices; + int i_cindex; + + __u32 i_generation; + +#ifdef CONFIG_DNOTIFY + unsigned long i_dnotify_mask; /* Directory notify events */ + struct dnotify_struct *i_dnotify; /* for directory notifications */ +#endif + +#ifdef CONFIG_INOTIFY + struct list_head inotify_watches; /* watches on this inode */ + struct mutex inotify_mutex; /* protects the watches list */ +#endif + + unsigned long i_state; + unsigned long dirtied_when; /* jiffies of first dirtying */ + + unsigned int i_flags; + +#ifdef CONFIG_SECURITY + void *i_security; +#endif + void *i_private; /* fs or device private pointer */ +}; + +struct super_block { + struct list_head s_list; /* Keep this first */ + dev_t s_dev; /* search index; _not_ kdev_t */ + unsigned long s_blocksize; + unsigned char s_blocksize_bits; + unsigned char s_dirt; + unsigned long long s_maxbytes; /* Max file size */ + struct file_system_type *s_type; + const struct super_operations *s_op; + struct dquot_operations *dq_op; + struct quotactl_ops *s_qcop; + const struct export_operations *s_export_op; + unsigned long s_flags; + unsigned long s_magic; + struct dentry *s_root; + struct rw_semaphore s_umount; + struct mutex s_lock; + int s_count; + int s_syncing; + int s_need_sync_fs; +#ifdef CONFIG_SECURITY + void *s_security; +#endif + struct xattr_handler **s_xattr; + + struct list_head s_inodes; /* all inodes */ + struct list_head s_dirty; /* dirty inodes */ + struct list_head s_io; /* parked for writeback */ + struct list_head s_more_io; /* parked for more writeback */ + struct hlist_head s_anon; /* anonymous dentries for (nfs) exporting */ + struct list_head s_files; + /* s_dentry_lru and s_nr_dentry_unused are protected by dcache_lock */ + struct list_head s_dentry_lru; /* unused dentry lru */ + int s_nr_dentry_unused; /* # of dentry on lru */ + + struct block_device *s_bdev; + struct mtd_info *s_mtd; + struct list_head s_instances; + + int s_frozen; + wait_queue_head_t s_wait_unfrozen; + + char s_id[32]; /* Informational name */ + + void *s_fs_info; /* Filesystem private info */ + + /* + * The next field is for VFS *only*. No filesystems have any business + * even looking at it. You had been warned. + */ + struct mutex s_vfs_rename_mutex; /* Kludge */ + + /* Granularity of c/m/atime in ns. + Cannot be worse than a second */ + u32 s_time_gran; + + /* + * Filesystem subtype. If non-empty the filesystem type field + * in /proc/mounts will be "type.subtype" + */ + char *s_subtype; + + /* + * Saved mount options for lazy filesystems using + * generic_show_options() + */ + char *s_options; +}; + +struct file_system_type { + const char *name; + int fs_flags; + int (*get_sb) (struct file_system_type *, int, + const char *, void *, struct vfsmount *); + void (*kill_sb) (struct super_block *); + struct module *owner; + struct file_system_type * next; + struct list_head fs_supers; +}; + +struct vfsmount { + struct list_head mnt_hash; + struct vfsmount *mnt_parent; /* fs we are mounted on */ + struct dentry *mnt_mountpoint; /* dentry of mountpoint */ + struct dentry *mnt_root; /* root of the mounted tree */ + struct super_block *mnt_sb; /* pointer to superblock */ + struct list_head mnt_mounts; /* list of children, anchored here */ + struct list_head mnt_child; /* and going through their mnt_child */ + int mnt_flags; + /* 4 bytes hole on 64bits arches */ + const char *mnt_devname; /* Name of device e.g. /dev/dsk/hda1 */ + struct list_head mnt_list; + struct list_head mnt_expire; /* link in fs-specific expiry list */ + struct list_head mnt_share; /* circular list of shared mounts */ + struct list_head mnt_slave_list;/* list of slave mounts */ + struct list_head mnt_slave; /* slave list entry */ + struct vfsmount *mnt_master; /* slave is on master->mnt_slave_list */ + struct mnt_namespace *mnt_ns; /* containing namespace */ + int mnt_id; /* mount identifier */ + int mnt_group_id; /* peer group identifier */ + /* + * We put mnt_count & mnt_expiry_mark at the end of struct vfsmount + * to let these frequently modified fields in a separate cache line + * (so that reads of mnt_flags wont ping-pong on SMP machines) + */ + int mnt_expiry_mark; /* true if marked for expiry */ + int mnt_pinned; + int mnt_ghosts; + /* + * This value is not stable unless all of the mnt_writers[] spinlocks + * are held, and all mnt_writer[]s on this mount have 0 as their ->count + */ +}; + +struct path { + struct vfsmount *mnt; + struct dentry *dentry; +}; + +struct file { + struct path f_path; +#define f_dentry f_path.dentry +#define f_vfsmnt f_path.mnt + const struct file_operations *f_op; + unsigned int f_flags; + loff_t f_pos; + unsigned int f_uid, f_gid; + + u64 f_version; +#ifdef CONFIG_SECURITY + void *f_security; +#endif + /* needed for tty driver, and maybe others */ + void *private_data; + +#ifdef CONFIG_EPOLL + /* Used by fs/eventpoll.c to link all the hooks to this file */ + struct list_head f_ep_links; + spinlock_t f_ep_lock; +#endif /* #ifdef CONFIG_EPOLL */ +#ifdef CONFIG_DEBUG_WRITECOUNT + unsigned long f_mnt_write_state; +#endif +}; + +/* + * get_seconds() not really needed in the read-only implmentation + */ +#define get_seconds() 0 + +/* 4k page size */ +#define PAGE_CACHE_SHIFT 12 +#define PAGE_CACHE_SIZE (1 << PAGE_CACHE_SHIFT) + +/* Page cache limit. The filesystems should put that into their s_maxbytes + limits, otherwise bad things can happen in VM. */ +#if BITS_PER_LONG==32 +#define MAX_LFS_FILESIZE (((u64)PAGE_CACHE_SIZE << (BITS_PER_LONG-1))-1) +#elif BITS_PER_LONG==64 +#define MAX_LFS_FILESIZE 0x7fffffffffffffffUL +#endif + +#define INT_MAX ((int)(~0U>>1)) +#define INT_MIN (-INT_MAX - 1) +#define LLONG_MAX ((long long)(~0ULL>>1)) + +/* + * These are the fs-independent mount-flags: up to 32 flags are supported + */ +#define MS_RDONLY 1 /* Mount read-only */ +#define MS_NOSUID 2 /* Ignore suid and sgid bits */ +#define MS_NODEV 4 /* Disallow access to device special files */ +#define MS_NOEXEC 8 /* Disallow program execution */ +#define MS_SYNCHRONOUS 16 /* Writes are synced at once */ +#define MS_REMOUNT 32 /* Alter flags of a mounted FS */ +#define MS_MANDLOCK 64 /* Allow mandatory locks on an FS */ +#define MS_DIRSYNC 128 /* Directory modifications are synchronous */ +#define MS_NOATIME 1024 /* Do not update access times. */ +#define MS_NODIRATIME 2048 /* Do not update directory access times */ +#define MS_BIND 4096 +#define MS_MOVE 8192 +#define MS_REC 16384 +#define MS_VERBOSE 32768 /* War is peace. Verbosity is silence. + MS_VERBOSE is deprecated. */ +#define MS_SILENT 32768 +#define MS_POSIXACL (1<<16) /* VFS does not apply the umask */ +#define MS_UNBINDABLE (1<<17) /* change to unbindable */ +#define MS_PRIVATE (1<<18) /* change to private */ +#define MS_SLAVE (1<<19) /* change to slave */ +#define MS_SHARED (1<<20) /* change to shared */ +#define MS_RELATIME (1<<21) /* Update atime relative to mtime/ctime. */ +#define MS_KERNMOUNT (1<<22) /* this is a kern_mount call */ +#define MS_I_VERSION (1<<23) /* Update inode I_version field */ +#define MS_ACTIVE (1<<30) +#define MS_NOUSER (1<<31) + +#define I_NEW 8 + +/* Inode flags - they have nothing to superblock flags now */ + +#define S_SYNC 1 /* Writes are synced at once */ +#define S_NOATIME 2 /* Do not update access times */ +#define S_APPEND 4 /* Append-only file */ +#define S_IMMUTABLE 8 /* Immutable file */ +#define S_DEAD 16 /* removed, but still open directory */ +#define S_NOQUOTA 32 /* Inode is not counted to quota */ +#define S_DIRSYNC 64 /* Directory modifications are synchronous */ +#define S_NOCMTIME 128 /* Do not update file c/mtime */ +#define S_SWAPFILE 256 /* Do not truncate: swapon got its bmaps */ +#define S_PRIVATE 512 /* Inode is fs-internal */ + +/* include/linux/stat.h */ + +#define S_IFMT 00170000 +#define S_IFSOCK 0140000 +#define S_IFLNK 0120000 +#define S_IFREG 0100000 +#define S_IFBLK 0060000 +#define S_IFDIR 0040000 +#define S_IFCHR 0020000 +#define S_IFIFO 0010000 +#define S_ISUID 0004000 +#define S_ISGID 0002000 +#define S_ISVTX 0001000 + +/* include/linux/fs.h */ + +/* + * File types + * + * NOTE! These match bits 12..15 of stat.st_mode + * (ie "(i_mode >> 12) & 15"). + */ +#define DT_UNKNOWN 0 +#define DT_FIFO 1 +#define DT_CHR 2 +#define DT_DIR 4 +#define DT_BLK 6 +#define DT_REG 8 +#define DT_LNK 10 +#define DT_SOCK 12 +#define DT_WHT 14 + +#define I_DIRTY_SYNC 1 +#define I_DIRTY_DATASYNC 2 +#define I_DIRTY_PAGES 4 +#define I_NEW 8 +#define I_WILL_FREE 16 +#define I_FREEING 32 +#define I_CLEAR 64 +#define __I_LOCK 7 +#define I_LOCK (1 << __I_LOCK) +#define __I_SYNC 8 +#define I_SYNC (1 << __I_SYNC) + +#define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES) + +/* linux/include/dcache.h */ + +#define DNAME_INLINE_LEN_MIN 36 + +struct dentry { + unsigned int d_flags; /* protected by d_lock */ + spinlock_t d_lock; /* per dentry lock */ + struct inode *d_inode; /* Where the name belongs to - NULL is + * negative */ + /* + * The next three fields are touched by __d_lookup. Place them here + * so they all fit in a cache line. + */ + struct hlist_node d_hash; /* lookup hash list */ + struct dentry *d_parent; /* parent directory */ + struct qstr d_name; + + struct list_head d_lru; /* LRU list */ + /* + * d_child and d_rcu can share memory + */ + struct list_head d_subdirs; /* our children */ + struct list_head d_alias; /* inode alias list */ + unsigned long d_time; /* used by d_revalidate */ + struct super_block *d_sb; /* The root of the dentry tree */ + void *d_fsdata; /* fs-specific data */ +#ifdef CONFIG_PROFILING + struct dcookie_struct *d_cookie; /* cookie, if any */ +#endif + int d_mounted; + unsigned char d_iname[DNAME_INLINE_LEN_MIN]; /* small names */ +}; + +static inline ino_t parent_ino(struct dentry *dentry) +{ + ino_t res; + + spin_lock(&dentry->d_lock); + res = dentry->d_parent->d_inode->i_ino; + spin_unlock(&dentry->d_lock); + return res; +} + +/* linux/include/linux/bitops.h */ + +#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG)) +#define BIT_WORD(nr) ((nr) / BITS_PER_LONG) + +/* linux/include/asm-generic/bitops/non-atomic.h */ + +/** + * __set_bit - Set a bit in memory + * @nr: the bit to set + * @addr: the address to start counting from + * + * Unlike set_bit(), this function is non-atomic and may be reordered. + * If it's called on the same region of memory simultaneously, the effect + * may be that only one operation succeeds. + */ +static inline void __set_bit(int nr, volatile unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); + + *p |= mask; +} + +static inline void __clear_bit(int nr, volatile unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); + + *p &= ~mask; +} + +/* debug.c */ + +#define DEFINE_SPINLOCK(...) +#define module_param_named(...) + +/* misc.h */ +#define mutex_lock_nested(...) +#define mutex_unlock_nested(...) +#define mutex_is_locked(...) 0 + +/* Version of this UBIFS implementation */ +#define UBIFS_VERSION 1 + +/* Normal UBIFS messages */ +#define ubifs_msg(fmt, ...) \ + printk(KERN_NOTICE "UBIFS: " fmt "\n", ##__VA_ARGS__) +/* UBIFS error messages */ +#define ubifs_err(fmt, ...) \ + printk(KERN_ERR "UBIFS error (pid %d): %s: " fmt "\n", 0, \ + __func__, ##__VA_ARGS__) +/* UBIFS warning messages */ +#define ubifs_warn(fmt, ...) \ + printk(KERN_WARNING "UBIFS warning (pid %d): %s: " fmt "\n", \ + 0, __func__, ##__VA_ARGS__) + +/* UBIFS file system VFS magic number */ +#define UBIFS_SUPER_MAGIC 0x24051905 + +/* Number of UBIFS blocks per VFS page */ +#define UBIFS_BLOCKS_PER_PAGE (PAGE_CACHE_SIZE / UBIFS_BLOCK_SIZE) +#define UBIFS_BLOCKS_PER_PAGE_SHIFT (PAGE_CACHE_SHIFT - UBIFS_BLOCK_SHIFT) + +/* "File system end of life" sequence number watermark */ +#define SQNUM_WARN_WATERMARK 0xFFFFFFFF00000000ULL +#define SQNUM_WATERMARK 0xFFFFFFFFFF000000ULL + +/* + * Minimum amount of LEBs reserved for the index. At present the index needs at + * least 2 LEBs: one for the index head and one for in-the-gaps method (which + * currently does not cater for the index head and so excludes it from + * consideration). + */ +#define MIN_INDEX_LEBS 2 + +/* Minimum amount of data UBIFS writes to the flash */ +#define MIN_WRITE_SZ (UBIFS_DATA_NODE_SZ + 8) + +/* + * Currently we do not support inode number overlapping and re-using, so this + * watermark defines dangerous inode number level. This should be fixed later, + * although it is difficult to exceed current limit. Another option is to use + * 64-bit inode numbers, but this means more overhead. + */ +#define INUM_WARN_WATERMARK 0xFFF00000 +#define INUM_WATERMARK 0xFFFFFF00 + +/* Largest key size supported in this implementation */ +#define CUR_MAX_KEY_LEN UBIFS_SK_LEN + +/* Maximum number of entries in each LPT (LEB category) heap */ +#define LPT_HEAP_SZ 256 + +/* + * Background thread name pattern. The numbers are UBI device and volume + * numbers. + */ +#define BGT_NAME_PATTERN "ubifs_bgt%d_%d" + +/* Default write-buffer synchronization timeout (5 secs) */ +#define DEFAULT_WBUF_TIMEOUT (5 * HZ) + +/* Maximum possible inode number (only 32-bit inodes are supported now) */ +#define MAX_INUM 0xFFFFFFFF + +/* Number of non-data journal heads */ +#define NONDATA_JHEADS_CNT 2 + +/* Garbage collector head */ +#define GCHD 0 +/* Base journal head number */ +#define BASEHD 1 +/* First "general purpose" journal head */ +#define DATAHD 2 + +/* 'No change' value for 'ubifs_change_lp()' */ +#define LPROPS_NC 0x80000001 + +/* + * There is no notion of truncation key because truncation nodes do not exist + * in TNC. However, when replaying, it is handy to introduce fake "truncation" + * keys for truncation nodes because the code becomes simpler. So we define + * %UBIFS_TRUN_KEY type. + */ +#define UBIFS_TRUN_KEY UBIFS_KEY_TYPES_CNT + +/* + * How much a directory entry/extended attribute entry adds to the parent/host + * inode. + */ +#define CALC_DENT_SIZE(name_len) ALIGN(UBIFS_DENT_NODE_SZ + (name_len) + 1, 8) + +/* How much an extended attribute adds to the host inode */ +#define CALC_XATTR_BYTES(data_len) ALIGN(UBIFS_INO_NODE_SZ + (data_len) + 1, 8) + +/* + * Znodes which were not touched for 'OLD_ZNODE_AGE' seconds are considered + * "old", and znode which were touched last 'YOUNG_ZNODE_AGE' seconds ago are + * considered "young". This is used by shrinker when selecting znode to trim + * off. + */ +#define OLD_ZNODE_AGE 20 +#define YOUNG_ZNODE_AGE 5 + +/* + * Some compressors, like LZO, may end up with more data then the input buffer. + * So UBIFS always allocates larger output buffer, to be sure the compressor + * will not corrupt memory in case of worst case compression. + */ +#define WORST_COMPR_FACTOR 2 + +/* Maximum expected tree height for use by bottom_up_buf */ +#define BOTTOM_UP_HEIGHT 64 + +/* Maximum number of data nodes to bulk-read */ +#define UBIFS_MAX_BULK_READ 32 + +/* + * Lockdep classes for UBIFS inode @ui_mutex. + */ +enum { + WB_MUTEX_1 = 0, + WB_MUTEX_2 = 1, + WB_MUTEX_3 = 2, +}; + +/* + * Znode flags (actually, bit numbers which store the flags). + * + * DIRTY_ZNODE: znode is dirty + * COW_ZNODE: znode is being committed and a new instance of this znode has to + * be created before changing this znode + * OBSOLETE_ZNODE: znode is obsolete, which means it was deleted, but it is + * still in the commit list and the ongoing commit operation + * will commit it, and delete this znode after it is done + */ +enum { + DIRTY_ZNODE = 0, + COW_ZNODE = 1, + OBSOLETE_ZNODE = 2, +}; + +/* + * Commit states. + * + * COMMIT_RESTING: commit is not wanted + * COMMIT_BACKGROUND: background commit has been requested + * COMMIT_REQUIRED: commit is required + * COMMIT_RUNNING_BACKGROUND: background commit is running + * COMMIT_RUNNING_REQUIRED: commit is running and it is required + * COMMIT_BROKEN: commit failed + */ +enum { + COMMIT_RESTING = 0, + COMMIT_BACKGROUND, + COMMIT_REQUIRED, + COMMIT_RUNNING_BACKGROUND, + COMMIT_RUNNING_REQUIRED, + COMMIT_BROKEN, +}; + +/* + * 'ubifs_scan_a_node()' return values. + * + * SCANNED_GARBAGE: scanned garbage + * SCANNED_EMPTY_SPACE: scanned empty space + * SCANNED_A_NODE: scanned a valid node + * SCANNED_A_CORRUPT_NODE: scanned a corrupted node + * SCANNED_A_BAD_PAD_NODE: scanned a padding node with invalid pad length + * + * Greater than zero means: 'scanned that number of padding bytes' + */ +enum { + SCANNED_GARBAGE = 0, + SCANNED_EMPTY_SPACE = -1, + SCANNED_A_NODE = -2, + SCANNED_A_CORRUPT_NODE = -3, + SCANNED_A_BAD_PAD_NODE = -4, +}; + +/* + * LPT cnode flag bits. + * + * DIRTY_CNODE: cnode is dirty + * COW_CNODE: cnode is being committed and must be copied before writing + * OBSOLETE_CNODE: cnode is being committed and has been copied (or deleted), + * so it can (and must) be freed when the commit is finished + */ +enum { + DIRTY_CNODE = 0, + COW_CNODE = 1, + OBSOLETE_CNODE = 2, +}; + +/* + * Dirty flag bits (lpt_drty_flgs) for LPT special nodes. + * + * LTAB_DIRTY: ltab node is dirty + * LSAVE_DIRTY: lsave node is dirty + */ +enum { + LTAB_DIRTY = 1, + LSAVE_DIRTY = 2, +}; + +/* + * Return codes used by the garbage collector. + * @LEB_FREED: the logical eraseblock was freed and is ready to use + * @LEB_FREED_IDX: indexing LEB was freed and can be used only after the commit + * @LEB_RETAINED: the logical eraseblock was freed and retained for GC purposes + */ +enum { + LEB_FREED, + LEB_FREED_IDX, + LEB_RETAINED, +}; + +/** + * struct ubifs_old_idx - index node obsoleted since last commit start. + * @rb: rb-tree node + * @lnum: LEB number of obsoleted index node + * @offs: offset of obsoleted index node + */ +struct ubifs_old_idx { + struct rb_node rb; + int lnum; + int offs; +}; + +/* The below union makes it easier to deal with keys */ +union ubifs_key { + uint8_t u8[CUR_MAX_KEY_LEN]; + uint32_t u32[CUR_MAX_KEY_LEN/4]; + uint64_t u64[CUR_MAX_KEY_LEN/8]; + __le32 j32[CUR_MAX_KEY_LEN/4]; +}; + +/** + * struct ubifs_scan_node - UBIFS scanned node information. + * @list: list of scanned nodes + * @key: key of node scanned (if it has one) + * @sqnum: sequence number + * @type: type of node scanned + * @offs: offset with LEB of node scanned + * @len: length of node scanned + * @node: raw node + */ +struct ubifs_scan_node { + struct list_head list; + union ubifs_key key; + unsigned long long sqnum; + int type; + int offs; + int len; + void *node; +}; + +/** + * struct ubifs_scan_leb - UBIFS scanned LEB information. + * @lnum: logical eraseblock number + * @nodes_cnt: number of nodes scanned + * @nodes: list of struct ubifs_scan_node + * @endpt: end point (and therefore the start of empty space) + * @ecc: read returned -EBADMSG + * @buf: buffer containing entire LEB scanned + */ +struct ubifs_scan_leb { + int lnum; + int nodes_cnt; + struct list_head nodes; + int endpt; + int ecc; + void *buf; +}; + +/** + * struct ubifs_gced_idx_leb - garbage-collected indexing LEB. + * @list: list + * @lnum: LEB number + * @unmap: OK to unmap this LEB + * + * This data structure is used to temporary store garbage-collected indexing + * LEBs - they are not released immediately, but only after the next commit. + * This is needed to guarantee recoverability. + */ +struct ubifs_gced_idx_leb { + struct list_head list; + int lnum; + int unmap; +}; + +/** + * struct ubifs_inode - UBIFS in-memory inode description. + * @vfs_inode: VFS inode description object + * @creat_sqnum: sequence number at time of creation + * @del_cmtno: commit number corresponding to the time the inode was deleted, + * protected by @c->commit_sem; + * @xattr_size: summarized size of all extended attributes in bytes + * @xattr_cnt: count of extended attributes this inode has + * @xattr_names: sum of lengths of all extended attribute names belonging to + * this inode + * @dirty: non-zero if the inode is dirty + * @xattr: non-zero if this is an extended attribute inode + * @bulk_read: non-zero if bulk-read should be used + * @ui_mutex: serializes inode write-back with the rest of VFS operations, + * serializes "clean <-> dirty" state changes, serializes bulk-read, + * protects @dirty, @bulk_read, @ui_size, and @xattr_size + * @ui_lock: protects @synced_i_size + * @synced_i_size: synchronized size of inode, i.e. the value of inode size + * currently stored on the flash; used only for regular file + * inodes + * @ui_size: inode size used by UBIFS when writing to flash + * @flags: inode flags (@UBIFS_COMPR_FL, etc) + * @compr_type: default compression type used for this inode + * @last_page_read: page number of last page read (for bulk read) + * @read_in_a_row: number of consecutive pages read in a row (for bulk read) + * @data_len: length of the data attached to the inode + * @data: inode's data + * + * @ui_mutex exists for two main reasons. At first it prevents inodes from + * being written back while UBIFS changing them, being in the middle of an VFS + * operation. This way UBIFS makes sure the inode fields are consistent. For + * example, in 'ubifs_rename()' we change 3 inodes simultaneously, and + * write-back must not write any of them before we have finished. + * + * The second reason is budgeting - UBIFS has to budget all operations. If an + * operation is going to mark an inode dirty, it has to allocate budget for + * this. It cannot just mark it dirty because there is no guarantee there will + * be enough flash space to write the inode back later. This means UBIFS has + * to have full control over inode "clean <-> dirty" transitions (and pages + * actually). But unfortunately, VFS marks inodes dirty in many places, and it + * does not ask the file-system if it is allowed to do so (there is a notifier, + * but it is not enough), i.e., there is no mechanism to synchronize with this. + * So UBIFS has its own inode dirty flag and its own mutex to serialize + * "clean <-> dirty" transitions. + * + * The @synced_i_size field is used to make sure we never write pages which are + * beyond last synchronized inode size. See 'ubifs_writepage()' for more + * information. + * + * The @ui_size is a "shadow" variable for @inode->i_size and UBIFS uses + * @ui_size instead of @inode->i_size. The reason for this is that UBIFS cannot + * make sure @inode->i_size is always changed under @ui_mutex, because it + * cannot call 'vmtruncate()' with @ui_mutex locked, because it would deadlock + * with 'ubifs_writepage()' (see file.c). All the other inode fields are + * changed under @ui_mutex, so they do not need "shadow" fields. Note, one + * could consider to rework locking and base it on "shadow" fields. + */ +struct ubifs_inode { + struct inode vfs_inode; + unsigned long long creat_sqnum; + unsigned long long del_cmtno; + unsigned int xattr_size; + unsigned int xattr_cnt; + unsigned int xattr_names; + unsigned int dirty:1; + unsigned int xattr:1; + unsigned int bulk_read:1; + unsigned int compr_type:2; + struct mutex ui_mutex; + spinlock_t ui_lock; + loff_t synced_i_size; + loff_t ui_size; + int flags; + pgoff_t last_page_read; + pgoff_t read_in_a_row; + int data_len; + void *data; +}; + +/** + * struct ubifs_unclean_leb - records a LEB recovered under read-only mode. + * @list: list + * @lnum: LEB number of recovered LEB + * @endpt: offset where recovery ended + * + * This structure records a LEB identified during recovery that needs to be + * cleaned but was not because UBIFS was mounted read-only. The information + * is used to clean the LEB when remounting to read-write mode. + */ +struct ubifs_unclean_leb { + struct list_head list; + int lnum; + int endpt; +}; + +/* + * LEB properties flags. + * + * LPROPS_UNCAT: not categorized + * LPROPS_DIRTY: dirty > free, dirty >= @c->dead_wm, not index + * LPROPS_DIRTY_IDX: dirty + free > @c->min_idx_node_sze and index + * LPROPS_FREE: free > 0, dirty < @c->dead_wm, not empty, not index + * LPROPS_HEAP_CNT: number of heaps used for storing categorized LEBs + * LPROPS_EMPTY: LEB is empty, not taken + * LPROPS_FREEABLE: free + dirty == leb_size, not index, not taken + * LPROPS_FRDI_IDX: free + dirty == leb_size and index, may be taken + * LPROPS_CAT_MASK: mask for the LEB categories above + * LPROPS_TAKEN: LEB was taken (this flag is not saved on the media) + * LPROPS_INDEX: LEB contains indexing nodes (this flag also exists on flash) + */ +enum { + LPROPS_UNCAT = 0, + LPROPS_DIRTY = 1, + LPROPS_DIRTY_IDX = 2, + LPROPS_FREE = 3, + LPROPS_HEAP_CNT = 3, + LPROPS_EMPTY = 4, + LPROPS_FREEABLE = 5, + LPROPS_FRDI_IDX = 6, + LPROPS_CAT_MASK = 15, + LPROPS_TAKEN = 16, + LPROPS_INDEX = 32, +}; + +/** + * struct ubifs_lprops - logical eraseblock properties. + * @free: amount of free space in bytes + * @dirty: amount of dirty space in bytes + * @flags: LEB properties flags (see above) + * @lnum: LEB number + * @list: list of same-category lprops (for LPROPS_EMPTY and LPROPS_FREEABLE) + * @hpos: heap position in heap of same-category lprops (other categories) + */ +struct ubifs_lprops { + int free; + int dirty; + int flags; + int lnum; + union { + struct list_head list; + int hpos; + }; +}; + +/** + * struct ubifs_lpt_lprops - LPT logical eraseblock properties. + * @free: amount of free space in bytes + * @dirty: amount of dirty space in bytes + * @tgc: trivial GC flag (1 => unmap after commit end) + * @cmt: commit flag (1 => reserved for commit) + */ +struct ubifs_lpt_lprops { + int free; + int dirty; + unsigned tgc:1; + unsigned cmt:1; +}; + +/** + * struct ubifs_lp_stats - statistics of eraseblocks in the main area. + * @empty_lebs: number of empty LEBs + * @taken_empty_lebs: number of taken LEBs + * @idx_lebs: number of indexing LEBs + * @total_free: total free space in bytes (includes all LEBs) + * @total_dirty: total dirty space in bytes (includes all LEBs) + * @total_used: total used space in bytes (does not include index LEBs) + * @total_dead: total dead space in bytes (does not include index LEBs) + * @total_dark: total dark space in bytes (does not include index LEBs) + * + * The @taken_empty_lebs field counts the LEBs that are in the transient state + * of having been "taken" for use but not yet written to. @taken_empty_lebs is + * needed to account correctly for @gc_lnum, otherwise @empty_lebs could be + * used by itself (in which case 'unused_lebs' would be a better name). In the + * case of @gc_lnum, it is "taken" at mount time or whenever a LEB is retained + * by GC, but unlike other empty LEBs that are "taken", it may not be written + * straight away (i.e. before the next commit start or unmount), so either + * @gc_lnum must be specially accounted for, or the current approach followed + * i.e. count it under @taken_empty_lebs. + * + * @empty_lebs includes @taken_empty_lebs. + * + * @total_used, @total_dead and @total_dark fields do not account indexing + * LEBs. + */ +struct ubifs_lp_stats { + int empty_lebs; + int taken_empty_lebs; + int idx_lebs; + long long total_free; + long long total_dirty; + long long total_used; + long long total_dead; + long long total_dark; +}; + +struct ubifs_nnode; + +/** + * struct ubifs_cnode - LEB Properties Tree common node. + * @parent: parent nnode + * @cnext: next cnode to commit + * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE) + * @iip: index in parent + * @level: level in the tree (zero for pnodes, greater than zero for nnodes) + * @num: node number + */ +struct ubifs_cnode { + struct ubifs_nnode *parent; + struct ubifs_cnode *cnext; + unsigned long flags; + int iip; + int level; + int num; +}; + +/** + * struct ubifs_pnode - LEB Properties Tree leaf node. + * @parent: parent nnode + * @cnext: next cnode to commit + * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE) + * @iip: index in parent + * @level: level in the tree (always zero for pnodes) + * @num: node number + * @lprops: LEB properties array + */ +struct ubifs_pnode { + struct ubifs_nnode *parent; + struct ubifs_cnode *cnext; + unsigned long flags; + int iip; + int level; + int num; + struct ubifs_lprops lprops[UBIFS_LPT_FANOUT]; +}; + +/** + * struct ubifs_nbranch - LEB Properties Tree internal node branch. + * @lnum: LEB number of child + * @offs: offset of child + * @nnode: nnode child + * @pnode: pnode child + * @cnode: cnode child + */ +struct ubifs_nbranch { + int lnum; + int offs; + union { + struct ubifs_nnode *nnode; + struct ubifs_pnode *pnode; + struct ubifs_cnode *cnode; + }; +}; + +/** + * struct ubifs_nnode - LEB Properties Tree internal node. + * @parent: parent nnode + * @cnext: next cnode to commit + * @flags: flags (%DIRTY_LPT_NODE or %OBSOLETE_LPT_NODE) + * @iip: index in parent + * @level: level in the tree (always greater than zero for nnodes) + * @num: node number + * @nbranch: branches to child nodes + */ +struct ubifs_nnode { + struct ubifs_nnode *parent; + struct ubifs_cnode *cnext; + unsigned long flags; + int iip; + int level; + int num; + struct ubifs_nbranch nbranch[UBIFS_LPT_FANOUT]; +}; + +/** + * struct ubifs_lpt_heap - heap of categorized lprops. + * @arr: heap array + * @cnt: number in heap + * @max_cnt: maximum number allowed in heap + * + * There are %LPROPS_HEAP_CNT heaps. + */ +struct ubifs_lpt_heap { + struct ubifs_lprops **arr; + int cnt; + int max_cnt; +}; + +/* + * Return codes for LPT scan callback function. + * + * LPT_SCAN_CONTINUE: continue scanning + * LPT_SCAN_ADD: add the LEB properties scanned to the tree in memory + * LPT_SCAN_STOP: stop scanning + */ +enum { + LPT_SCAN_CONTINUE = 0, + LPT_SCAN_ADD = 1, + LPT_SCAN_STOP = 2, +}; + +struct ubifs_info; + +/* Callback used by the 'ubifs_lpt_scan_nolock()' function */ +typedef int (*ubifs_lpt_scan_callback)(struct ubifs_info *c, + const struct ubifs_lprops *lprops, + int in_tree, void *data); + +/** + * struct ubifs_wbuf - UBIFS write-buffer. + * @c: UBIFS file-system description object + * @buf: write-buffer (of min. flash I/O unit size) + * @lnum: logical eraseblock number the write-buffer points to + * @offs: write-buffer offset in this logical eraseblock + * @avail: number of bytes available in the write-buffer + * @used: number of used bytes in the write-buffer + * @dtype: type of data stored in this LEB (%UBI_LONGTERM, %UBI_SHORTTERM, + * %UBI_UNKNOWN) + * @jhead: journal head the mutex belongs to (note, needed only to shut lockdep + * up by 'mutex_lock_nested()). + * @sync_callback: write-buffer synchronization callback + * @io_mutex: serializes write-buffer I/O + * @lock: serializes @buf, @lnum, @offs, @avail, @used, @next_ino and @inodes + * fields + * @timer: write-buffer timer + * @timeout: timer expire interval in jiffies + * @need_sync: it is set if its timer expired and needs sync + * @next_ino: points to the next position of the following inode number + * @inodes: stores the inode numbers of the nodes which are in wbuf + * + * The write-buffer synchronization callback is called when the write-buffer is + * synchronized in order to notify how much space was wasted due to + * write-buffer padding and how much free space is left in the LEB. + * + * Note: the fields @buf, @lnum, @offs, @avail and @used can be read under + * spin-lock or mutex because they are written under both mutex and spin-lock. + * @buf is appended to under mutex but overwritten under both mutex and + * spin-lock. Thus the data between @buf and @buf + @used can be read under + * spinlock. + */ +struct ubifs_wbuf { + struct ubifs_info *c; + void *buf; + int lnum; + int offs; + int avail; + int used; + int dtype; + int jhead; + int (*sync_callback)(struct ubifs_info *c, int lnum, int free, int pad); + struct mutex io_mutex; + spinlock_t lock; + int timeout; + int need_sync; + int next_ino; + ino_t *inodes; +}; + +/** + * struct ubifs_bud - bud logical eraseblock. + * @lnum: logical eraseblock number + * @start: where the (uncommitted) bud data starts + * @jhead: journal head number this bud belongs to + * @list: link in the list buds belonging to the same journal head + * @rb: link in the tree of all buds + */ +struct ubifs_bud { + int lnum; + int start; + int jhead; + struct list_head list; + struct rb_node rb; +}; + +/** + * struct ubifs_jhead - journal head. + * @wbuf: head's write-buffer + * @buds_list: list of bud LEBs belonging to this journal head + * + * Note, the @buds list is protected by the @c->buds_lock. + */ +struct ubifs_jhead { + struct ubifs_wbuf wbuf; + struct list_head buds_list; +}; + +/** + * struct ubifs_zbranch - key/coordinate/length branch stored in znodes. + * @key: key + * @znode: znode address in memory + * @lnum: LEB number of the target node (indexing node or data node) + * @offs: target node offset within @lnum + * @len: target node length + */ +struct ubifs_zbranch { + union ubifs_key key; + union { + struct ubifs_znode *znode; + void *leaf; + }; + int lnum; + int offs; + int len; +}; + +/** + * struct ubifs_znode - in-memory representation of an indexing node. + * @parent: parent znode or NULL if it is the root + * @cnext: next znode to commit + * @flags: znode flags (%DIRTY_ZNODE, %COW_ZNODE or %OBSOLETE_ZNODE) + * @time: last access time (seconds) + * @level: level of the entry in the TNC tree + * @child_cnt: count of child znodes + * @iip: index in parent's zbranch array + * @alt: lower bound of key range has altered i.e. child inserted at slot 0 + * @lnum: LEB number of the corresponding indexing node + * @offs: offset of the corresponding indexing node + * @len: length of the corresponding indexing node + * @zbranch: array of znode branches (@c->fanout elements) + */ +struct ubifs_znode { + struct ubifs_znode *parent; + struct ubifs_znode *cnext; + unsigned long flags; + unsigned long time; + int level; + int child_cnt; + int iip; + int alt; +#ifdef CONFIG_UBIFS_FS_DEBUG + int lnum, offs, len; +#endif + struct ubifs_zbranch zbranch[]; +}; + +/** + * struct bu_info - bulk-read information. + * @key: first data node key + * @zbranch: zbranches of data nodes to bulk read + * @buf: buffer to read into + * @buf_len: buffer length + * @gc_seq: GC sequence number to detect races with GC + * @cnt: number of data nodes for bulk read + * @blk_cnt: number of data blocks including holes + * @oef: end of file reached + */ +struct bu_info { + union ubifs_key key; + struct ubifs_zbranch zbranch[UBIFS_MAX_BULK_READ]; + void *buf; + int buf_len; + int gc_seq; + int cnt; + int blk_cnt; + int eof; +}; + +/** + * struct ubifs_node_range - node length range description data structure. + * @len: fixed node length + * @min_len: minimum possible node length + * @max_len: maximum possible node length + * + * If @max_len is %0, the node has fixed length @len. + */ +struct ubifs_node_range { + union { + int len; + int min_len; + }; + int max_len; +}; + +/** + * struct ubifs_compressor - UBIFS compressor description structure. + * @compr_type: compressor type (%UBIFS_COMPR_LZO, etc) + * @cc: cryptoapi compressor handle + * @comp_mutex: mutex used during compression + * @decomp_mutex: mutex used during decompression + * @name: compressor name + * @capi_name: cryptoapi compressor name + */ +struct ubifs_compressor { + int compr_type; + char *name; + char *capi_name; + int (*decompress)(const unsigned char *in, size_t in_len, + unsigned char *out, size_t *out_len); +}; + +/** + * struct ubifs_budget_req - budget requirements of an operation. + * + * @fast: non-zero if the budgeting should try to acquire budget quickly and + * should not try to call write-back + * @recalculate: non-zero if @idx_growth, @data_growth, and @dd_growth fields + * have to be re-calculated + * @new_page: non-zero if the operation adds a new page + * @dirtied_page: non-zero if the operation makes a page dirty + * @new_dent: non-zero if the operation adds a new directory entry + * @mod_dent: non-zero if the operation removes or modifies an existing + * directory entry + * @new_ino: non-zero if the operation adds a new inode + * @new_ino_d: now much data newly created inode contains + * @dirtied_ino: how many inodes the operation makes dirty + * @dirtied_ino_d: now much data dirtied inode contains + * @idx_growth: how much the index will supposedly grow + * @data_growth: how much new data the operation will supposedly add + * @dd_growth: how much data that makes other data dirty the operation will + * supposedly add + * + * @idx_growth, @data_growth and @dd_growth are not used in budget request. The + * budgeting subsystem caches index and data growth values there to avoid + * re-calculating them when the budget is released. However, if @idx_growth is + * %-1, it is calculated by the release function using other fields. + * + * An inode may contain 4KiB of data at max., thus the widths of @new_ino_d + * is 13 bits, and @dirtied_ino_d - 15, because up to 4 inodes may be made + * dirty by the re-name operation. + * + * Note, UBIFS aligns node lengths to 8-bytes boundary, so the requester has to + * make sure the amount of inode data which contribute to @new_ino_d and + * @dirtied_ino_d fields are aligned. + */ +struct ubifs_budget_req { + unsigned int fast:1; + unsigned int recalculate:1; +#ifndef UBIFS_DEBUG + unsigned int new_page:1; + unsigned int dirtied_page:1; + unsigned int new_dent:1; + unsigned int mod_dent:1; + unsigned int new_ino:1; + unsigned int new_ino_d:13; + unsigned int dirtied_ino:4; + unsigned int dirtied_ino_d:15; +#else + /* Not bit-fields to check for overflows */ + unsigned int new_page; + unsigned int dirtied_page; + unsigned int new_dent; + unsigned int mod_dent; + unsigned int new_ino; + unsigned int new_ino_d; + unsigned int dirtied_ino; + unsigned int dirtied_ino_d; +#endif + int idx_growth; + int data_growth; + int dd_growth; +}; + +/** + * struct ubifs_orphan - stores the inode number of an orphan. + * @rb: rb-tree node of rb-tree of orphans sorted by inode number + * @list: list head of list of orphans in order added + * @new_list: list head of list of orphans added since the last commit + * @cnext: next orphan to commit + * @dnext: next orphan to delete + * @inum: inode number + * @new: %1 => added since the last commit, otherwise %0 + */ +struct ubifs_orphan { + struct rb_node rb; + struct list_head list; + struct list_head new_list; + struct ubifs_orphan *cnext; + struct ubifs_orphan *dnext; + ino_t inum; + int new; +}; + +/** + * struct ubifs_mount_opts - UBIFS-specific mount options information. + * @unmount_mode: selected unmount mode (%0 default, %1 normal, %2 fast) + * @bulk_read: enable/disable bulk-reads (%0 default, %1 disabe, %2 enable) + * @chk_data_crc: enable/disable CRC data checking when reading data nodes + * (%0 default, %1 disabe, %2 enable) + * @override_compr: override default compressor (%0 - do not override and use + * superblock compressor, %1 - override and use compressor + * specified in @compr_type) + * @compr_type: compressor type to override the superblock compressor with + * (%UBIFS_COMPR_NONE, etc) + */ +struct ubifs_mount_opts { + unsigned int unmount_mode:2; + unsigned int bulk_read:2; + unsigned int chk_data_crc:2; + unsigned int override_compr:1; + unsigned int compr_type:2; +}; + +struct ubifs_debug_info; + +/** + * struct ubifs_info - UBIFS file-system description data structure + * (per-superblock). + * @vfs_sb: VFS @struct super_block object + * @bdi: backing device info object to make VFS happy and disable read-ahead + * + * @highest_inum: highest used inode number + * @max_sqnum: current global sequence number + * @cmt_no: commit number of the last successfully completed commit, protected + * by @commit_sem + * @cnt_lock: protects @highest_inum and @max_sqnum counters + * @fmt_version: UBIFS on-flash format version + * @uuid: UUID from super block + * + * @lhead_lnum: log head logical eraseblock number + * @lhead_offs: log head offset + * @ltail_lnum: log tail logical eraseblock number (offset is always 0) + * @log_mutex: protects the log, @lhead_lnum, @lhead_offs, @ltail_lnum, and + * @bud_bytes + * @min_log_bytes: minimum required number of bytes in the log + * @cmt_bud_bytes: used during commit to temporarily amount of bytes in + * committed buds + * + * @buds: tree of all buds indexed by bud LEB number + * @bud_bytes: how many bytes of flash is used by buds + * @buds_lock: protects the @buds tree, @bud_bytes, and per-journal head bud + * lists + * @jhead_cnt: count of journal heads + * @jheads: journal heads (head zero is base head) + * @max_bud_bytes: maximum number of bytes allowed in buds + * @bg_bud_bytes: number of bud bytes when background commit is initiated + * @old_buds: buds to be released after commit ends + * @max_bud_cnt: maximum number of buds + * + * @commit_sem: synchronizes committer with other processes + * @cmt_state: commit state + * @cs_lock: commit state lock + * @cmt_wq: wait queue to sleep on if the log is full and a commit is running + * + * @big_lpt: flag that LPT is too big to write whole during commit + * @no_chk_data_crc: do not check CRCs when reading data nodes (except during + * recovery) + * @bulk_read: enable bulk-reads + * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc) + * + * @tnc_mutex: protects the Tree Node Cache (TNC), @zroot, @cnext, @enext, and + * @calc_idx_sz + * @zroot: zbranch which points to the root index node and znode + * @cnext: next znode to commit + * @enext: next znode to commit to empty space + * @gap_lebs: array of LEBs used by the in-gaps commit method + * @cbuf: commit buffer + * @ileb_buf: buffer for commit in-the-gaps method + * @ileb_len: length of data in ileb_buf + * @ihead_lnum: LEB number of index head + * @ihead_offs: offset of index head + * @ilebs: pre-allocated index LEBs + * @ileb_cnt: number of pre-allocated index LEBs + * @ileb_nxt: next pre-allocated index LEBs + * @old_idx: tree of index nodes obsoleted since the last commit start + * @bottom_up_buf: a buffer which is used by 'dirty_cow_bottom_up()' in tnc.c + * + * @mst_node: master node + * @mst_offs: offset of valid master node + * @mst_mutex: protects the master node area, @mst_node, and @mst_offs + * + * @max_bu_buf_len: maximum bulk-read buffer length + * @bu_mutex: protects the pre-allocated bulk-read buffer and @c->bu + * @bu: pre-allocated bulk-read information + * + * @log_lebs: number of logical eraseblocks in the log + * @log_bytes: log size in bytes + * @log_last: last LEB of the log + * @lpt_lebs: number of LEBs used for lprops table + * @lpt_first: first LEB of the lprops table area + * @lpt_last: last LEB of the lprops table area + * @orph_lebs: number of LEBs used for the orphan area + * @orph_first: first LEB of the orphan area + * @orph_last: last LEB of the orphan area + * @main_lebs: count of LEBs in the main area + * @main_first: first LEB of the main area + * @main_bytes: main area size in bytes + * + * @key_hash_type: type of the key hash + * @key_hash: direntry key hash function + * @key_fmt: key format + * @key_len: key length + * @fanout: fanout of the index tree (number of links per indexing node) + * + * @min_io_size: minimal input/output unit size + * @min_io_shift: number of bits in @min_io_size minus one + * @leb_size: logical eraseblock size in bytes + * @half_leb_size: half LEB size + * @leb_cnt: count of logical eraseblocks + * @max_leb_cnt: maximum count of logical eraseblocks + * @old_leb_cnt: count of logical eraseblocks before re-size + * @ro_media: the underlying UBI volume is read-only + * + * @dirty_pg_cnt: number of dirty pages (not used) + * @dirty_zn_cnt: number of dirty znodes + * @clean_zn_cnt: number of clean znodes + * + * @budg_idx_growth: amount of bytes budgeted for index growth + * @budg_data_growth: amount of bytes budgeted for cached data + * @budg_dd_growth: amount of bytes budgeted for cached data that will make + * other data dirty + * @budg_uncommitted_idx: amount of bytes were budgeted for growth of the index, + * but which still have to be taken into account because + * the index has not been committed so far + * @space_lock: protects @budg_idx_growth, @budg_data_growth, @budg_dd_growth, + * @budg_uncommited_idx, @min_idx_lebs, @old_idx_sz, @lst, + * @nospace, and @nospace_rp; + * @min_idx_lebs: minimum number of LEBs required for the index + * @old_idx_sz: size of index on flash + * @calc_idx_sz: temporary variable which is used to calculate new index size + * (contains accurate new index size at end of TNC commit start) + * @lst: lprops statistics + * @nospace: non-zero if the file-system does not have flash space (used as + * optimization) + * @nospace_rp: the same as @nospace, but additionally means that even reserved + * pool is full + * + * @page_budget: budget for a page + * @inode_budget: budget for an inode + * @dent_budget: budget for a directory entry + * + * @ref_node_alsz: size of the LEB reference node aligned to the min. flash + * I/O unit + * @mst_node_alsz: master node aligned size + * @min_idx_node_sz: minimum indexing node aligned on 8-bytes boundary + * @max_idx_node_sz: maximum indexing node aligned on 8-bytes boundary + * @max_inode_sz: maximum possible inode size in bytes + * @max_znode_sz: size of znode in bytes + * + * @leb_overhead: how many bytes are wasted in an LEB when it is filled with + * data nodes of maximum size - used in free space reporting + * @dead_wm: LEB dead space watermark + * @dark_wm: LEB dark space watermark + * @block_cnt: count of 4KiB blocks on the FS + * + * @ranges: UBIFS node length ranges + * @ubi: UBI volume descriptor + * @di: UBI device information + * @vi: UBI volume information + * + * @orph_tree: rb-tree of orphan inode numbers + * @orph_list: list of orphan inode numbers in order added + * @orph_new: list of orphan inode numbers added since last commit + * @orph_cnext: next orphan to commit + * @orph_dnext: next orphan to delete + * @orphan_lock: lock for orph_tree and orph_new + * @orph_buf: buffer for orphan nodes + * @new_orphans: number of orphans since last commit + * @cmt_orphans: number of orphans being committed + * @tot_orphans: number of orphans in the rb_tree + * @max_orphans: maximum number of orphans allowed + * @ohead_lnum: orphan head LEB number + * @ohead_offs: orphan head offset + * @no_orphs: non-zero if there are no orphans + * + * @bgt: UBIFS background thread + * @bgt_name: background thread name + * @need_bgt: if background thread should run + * @need_wbuf_sync: if write-buffers have to be synchronized + * + * @gc_lnum: LEB number used for garbage collection + * @sbuf: a buffer of LEB size used by GC and replay for scanning + * @idx_gc: list of index LEBs that have been garbage collected + * @idx_gc_cnt: number of elements on the idx_gc list + * @gc_seq: incremented for every non-index LEB garbage collected + * @gced_lnum: last non-index LEB that was garbage collected + * + * @infos_list: links all 'ubifs_info' objects + * @umount_mutex: serializes shrinker and un-mount + * @shrinker_run_no: shrinker run number + * + * @space_bits: number of bits needed to record free or dirty space + * @lpt_lnum_bits: number of bits needed to record a LEB number in the LPT + * @lpt_offs_bits: number of bits needed to record an offset in the LPT + * @lpt_spc_bits: number of bits needed to space in the LPT + * @pcnt_bits: number of bits needed to record pnode or nnode number + * @lnum_bits: number of bits needed to record LEB number + * @nnode_sz: size of on-flash nnode + * @pnode_sz: size of on-flash pnode + * @ltab_sz: size of on-flash LPT lprops table + * @lsave_sz: size of on-flash LPT save table + * @pnode_cnt: number of pnodes + * @nnode_cnt: number of nnodes + * @lpt_hght: height of the LPT + * @pnodes_have: number of pnodes in memory + * + * @lp_mutex: protects lprops table and all the other lprops-related fields + * @lpt_lnum: LEB number of the root nnode of the LPT + * @lpt_offs: offset of the root nnode of the LPT + * @nhead_lnum: LEB number of LPT head + * @nhead_offs: offset of LPT head + * @lpt_drty_flgs: dirty flags for LPT special nodes e.g. ltab + * @dirty_nn_cnt: number of dirty nnodes + * @dirty_pn_cnt: number of dirty pnodes + * @check_lpt_free: flag that indicates LPT GC may be needed + * @lpt_sz: LPT size + * @lpt_nod_buf: buffer for an on-flash nnode or pnode + * @lpt_buf: buffer of LEB size used by LPT + * @nroot: address in memory of the root nnode of the LPT + * @lpt_cnext: next LPT node to commit + * @lpt_heap: array of heaps of categorized lprops + * @dirty_idx: a (reverse sorted) copy of the LPROPS_DIRTY_IDX heap as at + * previous commit start + * @uncat_list: list of un-categorized LEBs + * @empty_list: list of empty LEBs + * @freeable_list: list of freeable non-index LEBs (free + dirty == leb_size) + * @frdi_idx_list: list of freeable index LEBs (free + dirty == leb_size) + * @freeable_cnt: number of freeable LEBs in @freeable_list + * + * @ltab_lnum: LEB number of LPT's own lprops table + * @ltab_offs: offset of LPT's own lprops table + * @ltab: LPT's own lprops table + * @ltab_cmt: LPT's own lprops table (commit copy) + * @lsave_cnt: number of LEB numbers in LPT's save table + * @lsave_lnum: LEB number of LPT's save table + * @lsave_offs: offset of LPT's save table + * @lsave: LPT's save table + * @lscan_lnum: LEB number of last LPT scan + * + * @rp_size: size of the reserved pool in bytes + * @report_rp_size: size of the reserved pool reported to user-space + * @rp_uid: reserved pool user ID + * @rp_gid: reserved pool group ID + * + * @empty: if the UBI device is empty + * @replay_tree: temporary tree used during journal replay + * @replay_list: temporary list used during journal replay + * @replay_buds: list of buds to replay + * @cs_sqnum: sequence number of first node in the log (commit start node) + * @replay_sqnum: sequence number of node currently being replayed + * @need_recovery: file-system needs recovery + * @replaying: set to %1 during journal replay + * @unclean_leb_list: LEBs to recover when mounting ro to rw + * @rcvrd_mst_node: recovered master node to write when mounting ro to rw + * @size_tree: inode size information for recovery + * @remounting_rw: set while remounting from ro to rw (sb flags have MS_RDONLY) + * @always_chk_crc: always check CRCs (while mounting and remounting rw) + * @mount_opts: UBIFS-specific mount options + * + * @dbg: debugging-related information + */ +struct ubifs_info { + struct super_block *vfs_sb; + + ino_t highest_inum; + unsigned long long max_sqnum; + unsigned long long cmt_no; + spinlock_t cnt_lock; + int fmt_version; + unsigned char uuid[16]; + + int lhead_lnum; + int lhead_offs; + int ltail_lnum; + struct mutex log_mutex; + int min_log_bytes; + long long cmt_bud_bytes; + + struct rb_root buds; + long long bud_bytes; + spinlock_t buds_lock; + int jhead_cnt; + struct ubifs_jhead *jheads; + long long max_bud_bytes; + long long bg_bud_bytes; + struct list_head old_buds; + int max_bud_cnt; + + struct rw_semaphore commit_sem; + int cmt_state; + spinlock_t cs_lock; + wait_queue_head_t cmt_wq; + + unsigned int big_lpt:1; + unsigned int no_chk_data_crc:1; + unsigned int bulk_read:1; + unsigned int default_compr:2; + + struct mutex tnc_mutex; + struct ubifs_zbranch zroot; + struct ubifs_znode *cnext; + struct ubifs_znode *enext; + int *gap_lebs; + void *cbuf; + void *ileb_buf; + int ileb_len; + int ihead_lnum; + int ihead_offs; + int *ilebs; + int ileb_cnt; + int ileb_nxt; + struct rb_root old_idx; + int *bottom_up_buf; + + struct ubifs_mst_node *mst_node; + int mst_offs; + struct mutex mst_mutex; + + int max_bu_buf_len; + struct mutex bu_mutex; + struct bu_info bu; + + int log_lebs; + long long log_bytes; + int log_last; + int lpt_lebs; + int lpt_first; + int lpt_last; + int orph_lebs; + int orph_first; + int orph_last; + int main_lebs; + int main_first; + long long main_bytes; + + uint8_t key_hash_type; + uint32_t (*key_hash)(const char *str, int len); + int key_fmt; + int key_len; + int fanout; + + int min_io_size; + int min_io_shift; + int leb_size; + int half_leb_size; + int leb_cnt; + int max_leb_cnt; + int old_leb_cnt; + int ro_media; + + long long budg_idx_growth; + long long budg_data_growth; + long long budg_dd_growth; + long long budg_uncommitted_idx; + spinlock_t space_lock; + int min_idx_lebs; + unsigned long long old_idx_sz; + unsigned long long calc_idx_sz; + struct ubifs_lp_stats lst; + unsigned int nospace:1; + unsigned int nospace_rp:1; + + int page_budget; + int inode_budget; + int dent_budget; + + int ref_node_alsz; + int mst_node_alsz; + int min_idx_node_sz; + int max_idx_node_sz; + long long max_inode_sz; + int max_znode_sz; + + int leb_overhead; + int dead_wm; + int dark_wm; + int block_cnt; + + struct ubifs_node_range ranges[UBIFS_NODE_TYPES_CNT]; + struct ubi_volume_desc *ubi; + struct ubi_device_info di; + struct ubi_volume_info vi; + + struct rb_root orph_tree; + struct list_head orph_list; + struct list_head orph_new; + struct ubifs_orphan *orph_cnext; + struct ubifs_orphan *orph_dnext; + spinlock_t orphan_lock; + void *orph_buf; + int new_orphans; + int cmt_orphans; + int tot_orphans; + int max_orphans; + int ohead_lnum; + int ohead_offs; + int no_orphs; + + struct task_struct *bgt; + char bgt_name[sizeof(BGT_NAME_PATTERN) + 9]; + int need_bgt; + int need_wbuf_sync; + + int gc_lnum; + void *sbuf; + struct list_head idx_gc; + int idx_gc_cnt; + int gc_seq; + int gced_lnum; + + struct list_head infos_list; + struct mutex umount_mutex; + unsigned int shrinker_run_no; + + int space_bits; + int lpt_lnum_bits; + int lpt_offs_bits; + int lpt_spc_bits; + int pcnt_bits; + int lnum_bits; + int nnode_sz; + int pnode_sz; + int ltab_sz; + int lsave_sz; + int pnode_cnt; + int nnode_cnt; + int lpt_hght; + int pnodes_have; + + struct mutex lp_mutex; + int lpt_lnum; + int lpt_offs; + int nhead_lnum; + int nhead_offs; + int lpt_drty_flgs; + int dirty_nn_cnt; + int dirty_pn_cnt; + int check_lpt_free; + long long lpt_sz; + void *lpt_nod_buf; + void *lpt_buf; + struct ubifs_nnode *nroot; + struct ubifs_cnode *lpt_cnext; + struct ubifs_lpt_heap lpt_heap[LPROPS_HEAP_CNT]; + struct ubifs_lpt_heap dirty_idx; + struct list_head uncat_list; + struct list_head empty_list; + struct list_head freeable_list; + struct list_head frdi_idx_list; + int freeable_cnt; + + int ltab_lnum; + int ltab_offs; + struct ubifs_lpt_lprops *ltab; + struct ubifs_lpt_lprops *ltab_cmt; + int lsave_cnt; + int lsave_lnum; + int lsave_offs; + int *lsave; + int lscan_lnum; + + long long rp_size; + long long report_rp_size; + uid_t rp_uid; + gid_t rp_gid; + + /* The below fields are used only during mounting and re-mounting */ + int empty; + struct rb_root replay_tree; + struct list_head replay_list; + struct list_head replay_buds; + unsigned long long cs_sqnum; + unsigned long long replay_sqnum; + int need_recovery; + int replaying; + struct list_head unclean_leb_list; + struct ubifs_mst_node *rcvrd_mst_node; + struct rb_root size_tree; + int remounting_rw; + int always_chk_crc; + struct ubifs_mount_opts mount_opts; + +#ifdef CONFIG_UBIFS_FS_DEBUG + struct ubifs_debug_info *dbg; +#endif +}; + +extern spinlock_t ubifs_infos_lock; +extern struct kmem_cache *ubifs_inode_slab; +extern const struct super_operations ubifs_super_operations; +extern const struct address_space_operations ubifs_file_address_operations; +extern const struct file_operations ubifs_file_operations; +extern const struct inode_operations ubifs_file_inode_operations; +extern const struct file_operations ubifs_dir_operations; +extern const struct inode_operations ubifs_dir_inode_operations; +extern const struct inode_operations ubifs_symlink_inode_operations; +extern struct backing_dev_info ubifs_backing_dev_info; +extern struct ubifs_compressor *ubifs_compressors[UBIFS_COMPR_TYPES_CNT]; + +/* io.c */ +void ubifs_ro_mode(struct ubifs_info *c, int err); +int ubifs_wbuf_write_nolock(struct ubifs_wbuf *wbuf, void *buf, int len); +int ubifs_wbuf_seek_nolock(struct ubifs_wbuf *wbuf, int lnum, int offs, + int dtype); +int ubifs_wbuf_init(struct ubifs_info *c, struct ubifs_wbuf *wbuf); +int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len, + int lnum, int offs); +int ubifs_read_node_wbuf(struct ubifs_wbuf *wbuf, void *buf, int type, int len, + int lnum, int offs); +int ubifs_write_node(struct ubifs_info *c, void *node, int len, int lnum, + int offs, int dtype); +int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum, + int offs, int quiet, int must_chk_crc); +void ubifs_prepare_node(struct ubifs_info *c, void *buf, int len, int pad); +void ubifs_prep_grp_node(struct ubifs_info *c, void *node, int len, int last); +int ubifs_io_init(struct ubifs_info *c); +void ubifs_pad(const struct ubifs_info *c, void *buf, int pad); +int ubifs_wbuf_sync_nolock(struct ubifs_wbuf *wbuf); +int ubifs_bg_wbufs_sync(struct ubifs_info *c); +void ubifs_wbuf_add_ino_nolock(struct ubifs_wbuf *wbuf, ino_t inum); +int ubifs_sync_wbufs_by_inode(struct ubifs_info *c, struct inode *inode); + +/* scan.c */ +struct ubifs_scan_leb *ubifs_scan(const struct ubifs_info *c, int lnum, + int offs, void *sbuf); +void ubifs_scan_destroy(struct ubifs_scan_leb *sleb); +int ubifs_scan_a_node(const struct ubifs_info *c, void *buf, int len, int lnum, + int offs, int quiet); +struct ubifs_scan_leb *ubifs_start_scan(const struct ubifs_info *c, int lnum, + int offs, void *sbuf); +void ubifs_end_scan(const struct ubifs_info *c, struct ubifs_scan_leb *sleb, + int lnum, int offs); +int ubifs_add_snod(const struct ubifs_info *c, struct ubifs_scan_leb *sleb, + void *buf, int offs); +void ubifs_scanned_corruption(const struct ubifs_info *c, int lnum, int offs, + void *buf); + +/* log.c */ +void ubifs_add_bud(struct ubifs_info *c, struct ubifs_bud *bud); +void ubifs_create_buds_lists(struct ubifs_info *c); +int ubifs_add_bud_to_log(struct ubifs_info *c, int jhead, int lnum, int offs); +struct ubifs_bud *ubifs_search_bud(struct ubifs_info *c, int lnum); +struct ubifs_wbuf *ubifs_get_wbuf(struct ubifs_info *c, int lnum); +int ubifs_log_start_commit(struct ubifs_info *c, int *ltail_lnum); +int ubifs_log_end_commit(struct ubifs_info *c, int new_ltail_lnum); +int ubifs_log_post_commit(struct ubifs_info *c, int old_ltail_lnum); +int ubifs_consolidate_log(struct ubifs_info *c); + +/* journal.c */ +int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir, + const struct qstr *nm, const struct inode *inode, + int deletion, int xent); +int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode, + const union ubifs_key *key, const void *buf, int len); +int ubifs_jnl_write_inode(struct ubifs_info *c, const struct inode *inode); +int ubifs_jnl_delete_inode(struct ubifs_info *c, const struct inode *inode); +int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir, + const struct dentry *old_dentry, + const struct inode *new_dir, + const struct dentry *new_dentry, int sync); +int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode, + loff_t old_size, loff_t new_size); +int ubifs_jnl_delete_xattr(struct ubifs_info *c, const struct inode *host, + const struct inode *inode, const struct qstr *nm); +int ubifs_jnl_change_xattr(struct ubifs_info *c, const struct inode *inode1, + const struct inode *inode2); + +/* budget.c */ +int ubifs_budget_space(struct ubifs_info *c, struct ubifs_budget_req *req); +void ubifs_release_budget(struct ubifs_info *c, struct ubifs_budget_req *req); +void ubifs_release_dirty_inode_budget(struct ubifs_info *c, + struct ubifs_inode *ui); +int ubifs_budget_inode_op(struct ubifs_info *c, struct inode *inode, + struct ubifs_budget_req *req); +void ubifs_release_ino_dirty(struct ubifs_info *c, struct inode *inode, + struct ubifs_budget_req *req); +void ubifs_cancel_ino_op(struct ubifs_info *c, struct inode *inode, + struct ubifs_budget_req *req); +long long ubifs_get_free_space(struct ubifs_info *c); +long long ubifs_get_free_space_nolock(struct ubifs_info *c); +int ubifs_calc_min_idx_lebs(struct ubifs_info *c); +void ubifs_convert_page_budget(struct ubifs_info *c); +long long ubifs_reported_space(const struct ubifs_info *c, long long free); +long long ubifs_calc_available(const struct ubifs_info *c, int min_idx_lebs); + +/* find.c */ +int ubifs_find_free_space(struct ubifs_info *c, int min_space, int *free, + int squeeze); +int ubifs_find_free_leb_for_idx(struct ubifs_info *c); +int ubifs_find_dirty_leb(struct ubifs_info *c, struct ubifs_lprops *ret_lp, + int min_space, int pick_free); +int ubifs_find_dirty_idx_leb(struct ubifs_info *c); +int ubifs_save_dirty_idx_lnums(struct ubifs_info *c); + +/* tnc.c */ +int ubifs_lookup_level0(struct ubifs_info *c, const union ubifs_key *key, + struct ubifs_znode **zn, int *n); +int ubifs_tnc_lookup_nm(struct ubifs_info *c, const union ubifs_key *key, + void *node, const struct qstr *nm); +int ubifs_tnc_locate(struct ubifs_info *c, const union ubifs_key *key, + void *node, int *lnum, int *offs); +int ubifs_tnc_add(struct ubifs_info *c, const union ubifs_key *key, int lnum, + int offs, int len); +int ubifs_tnc_replace(struct ubifs_info *c, const union ubifs_key *key, + int old_lnum, int old_offs, int lnum, int offs, int len); +int ubifs_tnc_add_nm(struct ubifs_info *c, const union ubifs_key *key, + int lnum, int offs, int len, const struct qstr *nm); +int ubifs_tnc_remove(struct ubifs_info *c, const union ubifs_key *key); +int ubifs_tnc_remove_nm(struct ubifs_info *c, const union ubifs_key *key, + const struct qstr *nm); +int ubifs_tnc_remove_range(struct ubifs_info *c, union ubifs_key *from_key, + union ubifs_key *to_key); +int ubifs_tnc_remove_ino(struct ubifs_info *c, ino_t inum); +struct ubifs_dent_node *ubifs_tnc_next_ent(struct ubifs_info *c, + union ubifs_key *key, + const struct qstr *nm); +void ubifs_tnc_close(struct ubifs_info *c); +int ubifs_tnc_has_node(struct ubifs_info *c, union ubifs_key *key, int level, + int lnum, int offs, int is_idx); +int ubifs_dirty_idx_node(struct ubifs_info *c, union ubifs_key *key, int level, + int lnum, int offs); +/* Shared by tnc.c for tnc_commit.c */ +void destroy_old_idx(struct ubifs_info *c); +int is_idx_node_in_tnc(struct ubifs_info *c, union ubifs_key *key, int level, + int lnum, int offs); +int insert_old_idx_znode(struct ubifs_info *c, struct ubifs_znode *znode); +int ubifs_tnc_get_bu_keys(struct ubifs_info *c, struct bu_info *bu); +int ubifs_tnc_bulk_read(struct ubifs_info *c, struct bu_info *bu); + +/* tnc_misc.c */ +struct ubifs_znode *ubifs_tnc_levelorder_next(struct ubifs_znode *zr, + struct ubifs_znode *znode); +int ubifs_search_zbranch(const struct ubifs_info *c, + const struct ubifs_znode *znode, + const union ubifs_key *key, int *n); +struct ubifs_znode *ubifs_tnc_postorder_first(struct ubifs_znode *znode); +struct ubifs_znode *ubifs_tnc_postorder_next(struct ubifs_znode *znode); +long ubifs_destroy_tnc_subtree(struct ubifs_znode *zr); +struct ubifs_znode *ubifs_load_znode(struct ubifs_info *c, + struct ubifs_zbranch *zbr, + struct ubifs_znode *parent, int iip); +int ubifs_tnc_read_node(struct ubifs_info *c, struct ubifs_zbranch *zbr, + void *node); + +/* tnc_commit.c */ +int ubifs_tnc_start_commit(struct ubifs_info *c, struct ubifs_zbranch *zroot); +int ubifs_tnc_end_commit(struct ubifs_info *c); + +/* shrinker.c */ +int ubifs_shrinker(int nr_to_scan, gfp_t gfp_mask); + +/* commit.c */ +int ubifs_bg_thread(void *info); +void ubifs_commit_required(struct ubifs_info *c); +void ubifs_request_bg_commit(struct ubifs_info *c); +int ubifs_run_commit(struct ubifs_info *c); +void ubifs_recovery_commit(struct ubifs_info *c); +int ubifs_gc_should_commit(struct ubifs_info *c); +void ubifs_wait_for_commit(struct ubifs_info *c); + +/* master.c */ +int ubifs_read_master(struct ubifs_info *c); +int ubifs_write_master(struct ubifs_info *c); + +/* sb.c */ +int ubifs_read_superblock(struct ubifs_info *c); +struct ubifs_sb_node *ubifs_read_sb_node(struct ubifs_info *c); +int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup); + +/* replay.c */ +int ubifs_validate_entry(struct ubifs_info *c, + const struct ubifs_dent_node *dent); +int ubifs_replay_journal(struct ubifs_info *c); + +/* gc.c */ +int ubifs_garbage_collect(struct ubifs_info *c, int anyway); +int ubifs_gc_start_commit(struct ubifs_info *c); +int ubifs_gc_end_commit(struct ubifs_info *c); +void ubifs_destroy_idx_gc(struct ubifs_info *c); +int ubifs_get_idx_gc_leb(struct ubifs_info *c); +int ubifs_garbage_collect_leb(struct ubifs_info *c, struct ubifs_lprops *lp); + +/* orphan.c */ +int ubifs_add_orphan(struct ubifs_info *c, ino_t inum); +void ubifs_delete_orphan(struct ubifs_info *c, ino_t inum); +int ubifs_orphan_start_commit(struct ubifs_info *c); +int ubifs_orphan_end_commit(struct ubifs_info *c); +int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only); +int ubifs_clear_orphans(struct ubifs_info *c); + +/* lpt.c */ +int ubifs_calc_lpt_geom(struct ubifs_info *c); +int ubifs_create_dflt_lpt(struct ubifs_info *c, int *main_lebs, int lpt_first, + int *lpt_lebs, int *big_lpt); +int ubifs_lpt_init(struct ubifs_info *c, int rd, int wr); +struct ubifs_lprops *ubifs_lpt_lookup(struct ubifs_info *c, int lnum); +struct ubifs_lprops *ubifs_lpt_lookup_dirty(struct ubifs_info *c, int lnum); +int ubifs_lpt_scan_nolock(struct ubifs_info *c, int start_lnum, int end_lnum, + ubifs_lpt_scan_callback scan_cb, void *data); + +/* Shared by lpt.c for lpt_commit.c */ +void ubifs_pack_lsave(struct ubifs_info *c, void *buf, int *lsave); +void ubifs_pack_ltab(struct ubifs_info *c, void *buf, + struct ubifs_lpt_lprops *ltab); +void ubifs_pack_pnode(struct ubifs_info *c, void *buf, + struct ubifs_pnode *pnode); +void ubifs_pack_nnode(struct ubifs_info *c, void *buf, + struct ubifs_nnode *nnode); +struct ubifs_pnode *ubifs_get_pnode(struct ubifs_info *c, + struct ubifs_nnode *parent, int iip); +struct ubifs_nnode *ubifs_get_nnode(struct ubifs_info *c, + struct ubifs_nnode *parent, int iip); +int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip); +void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty); +void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode); +uint32_t ubifs_unpack_bits(uint8_t **addr, int *pos, int nrbits); +struct ubifs_nnode *ubifs_first_nnode(struct ubifs_info *c, int *hght); +/* Needed only in debugging code in lpt_commit.c */ +int ubifs_unpack_nnode(const struct ubifs_info *c, void *buf, + struct ubifs_nnode *nnode); + +/* lpt_commit.c */ +int ubifs_lpt_start_commit(struct ubifs_info *c); +int ubifs_lpt_end_commit(struct ubifs_info *c); +int ubifs_lpt_post_commit(struct ubifs_info *c); +void ubifs_lpt_free(struct ubifs_info *c, int wr_only); + +/* lprops.c */ +const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c, + const struct ubifs_lprops *lp, + int free, int dirty, int flags, + int idx_gc_cnt); +void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst); +void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops, + int cat); +void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops, + struct ubifs_lprops *new_lprops); +void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops); +int ubifs_categorize_lprops(const struct ubifs_info *c, + const struct ubifs_lprops *lprops); +int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty, + int flags_set, int flags_clean, int idx_gc_cnt); +int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty, + int flags_set, int flags_clean); +int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp); +const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c); +const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c); +const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c); +const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c); + +/* file.c */ +int ubifs_fsync(struct file *file, struct dentry *dentry, int datasync); +int ubifs_setattr(struct dentry *dentry, struct iattr *attr); + +/* dir.c */ +struct inode *ubifs_new_inode(struct ubifs_info *c, const struct inode *dir, + int mode); +int ubifs_getattr(struct vfsmount *mnt, struct dentry *dentry, + struct kstat *stat); + +/* xattr.c */ +int ubifs_setxattr(struct dentry *dentry, const char *name, + const void *value, size_t size, int flags); +ssize_t ubifs_getxattr(struct dentry *dentry, const char *name, void *buf, + size_t size); +ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size); +int ubifs_removexattr(struct dentry *dentry, const char *name); + +/* super.c */ +struct inode *ubifs_iget(struct super_block *sb, unsigned long inum); +int ubifs_iput(struct inode *inode); + +/* recovery.c */ +int ubifs_recover_master_node(struct ubifs_info *c); +int ubifs_write_rcvrd_mst_node(struct ubifs_info *c); +struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum, + int offs, void *sbuf, int grouped); +struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum, + int offs, void *sbuf); +int ubifs_recover_inl_heads(const struct ubifs_info *c, void *sbuf); +int ubifs_clean_lebs(const struct ubifs_info *c, void *sbuf); +int ubifs_rcvry_gc_commit(struct ubifs_info *c); +int ubifs_recover_size_accum(struct ubifs_info *c, union ubifs_key *key, + int deletion, loff_t new_size); +int ubifs_recover_size(struct ubifs_info *c); +void ubifs_destroy_size_tree(struct ubifs_info *c); + +/* ioctl.c */ +long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg); +void ubifs_set_inode_flags(struct inode *inode); +#ifdef CONFIG_COMPAT +long ubifs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg); +#endif + +/* compressor.c */ +int __init ubifs_compressors_init(void); +void __exit ubifs_compressors_exit(void); +void ubifs_compress(const void *in_buf, int in_len, void *out_buf, int *out_len, + int *compr_type); +int ubifs_decompress(const void *buf, int len, void *out, int *out_len, + int compr_type); + +#include "debug.h" +#include "misc.h" +#include "key.h" + +/* todo: Move these to a common U-Boot header */ +int lzo1x_decompress_safe(const unsigned char *in, size_t in_len, + unsigned char *out, size_t *out_len); +int gunzip(void *dst, int dstlen, unsigned char *src, unsigned long *lenp); + +#endif /* !__UBIFS_H__ */ |