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authorHeiko Schocher <hs@denx.de>2014-06-24 10:10:04 +0200
committerTom Rini <trini@ti.com>2014-08-25 19:25:55 -0400
commitff94bc40af3481d47546595ba73c136de6af6929 (patch)
tree858119077e2ca8a992589185c36bd431e4a8c80e /fs/ubifs/recovery.c
parent0c06db59836746c5caf397e642cd0f2bf1cc20a6 (diff)
downloadu-boot-imx-ff94bc40af3481d47546595ba73c136de6af6929.zip
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mtd, ubi, ubifs: resync with Linux-3.14
resync ubi subsystem with linux: commit 455c6fdbd219161bd09b1165f11699d6d73de11c Author: Linus Torvalds <torvalds@linux-foundation.org> Date: Sun Mar 30 20:40:15 2014 -0700 Linux 3.14 A nice side effect of this, is we introduce UBI Fastmap support to U-Boot. Signed-off-by: Heiko Schocher <hs@denx.de> Signed-off-by: Tom Rini <trini@ti.com> Cc: Marek Vasut <marex@denx.de> Cc: Sergey Lapin <slapin@ossfans.org> Cc: Scott Wood <scottwood@freescale.com> Cc: Joerg Krause <jkrause@posteo.de>
Diffstat (limited to 'fs/ubifs/recovery.c')
-rw-r--r--fs/ubifs/recovery.c738
1 files changed, 538 insertions, 200 deletions
diff --git a/fs/ubifs/recovery.c b/fs/ubifs/recovery.c
index 7444650..f54a440 100644
--- a/fs/ubifs/recovery.c
+++ b/fs/ubifs/recovery.c
@@ -3,18 +3,7 @@
*
* 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
+ * SPDX-License-Identifier: GPL-2.0+
*
* Authors: Adrian Hunter
* Artem Bityutskiy (Битюцкий Артём)
@@ -23,13 +12,37 @@
/*
* 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.
+ * an un-mount was completed successfully. If not, the process of mounting
+ * incorporates 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.
+ *
+ * The general UBIFS approach to the recovery is that it recovers from
+ * corruptions which could be caused by power cuts, but it refuses to recover
+ * from corruption caused by other reasons. And UBIFS tries to distinguish
+ * between these 2 reasons of corruptions and silently recover in the former
+ * case and loudly complain in the latter case.
+ *
+ * UBIFS writes only to erased LEBs, so it writes only to the flash space
+ * containing only 0xFFs. UBIFS also always writes strictly from the beginning
+ * of the LEB to the end. And UBIFS assumes that the underlying flash media
+ * writes in @c->max_write_size bytes at a time.
+ *
+ * Hence, if UBIFS finds a corrupted node at offset X, it expects only the min.
+ * I/O unit corresponding to offset X to contain corrupted data, all the
+ * following min. I/O units have to contain empty space (all 0xFFs). If this is
+ * not true, the corruption cannot be the result of a power cut, and UBIFS
+ * refuses to mount.
*/
+#define __UBOOT__
+#ifndef __UBOOT__
+#include <linux/crc32.h>
+#include <linux/slab.h>
+#else
+#include <linux/err.h>
+#endif
#include "ubifs.h"
/**
@@ -52,6 +65,25 @@ static int is_empty(void *buf, int len)
}
/**
+ * first_non_ff - find offset of the first non-0xff byte.
+ * @buf: buffer to search in
+ * @len: length of buffer
+ *
+ * This function returns offset of the first non-0xff byte in @buf or %-1 if
+ * the buffer contains only 0xff bytes.
+ */
+static int first_non_ff(void *buf, int len)
+{
+ uint8_t *p = buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ if (*p++ != 0xff)
+ return i;
+ return -1;
+}
+
+/**
* get_master_node - get the last valid master node allowing for corruption.
* @c: UBIFS file-system description object
* @lnum: LEB number
@@ -79,7 +111,7 @@ static int get_master_node(const struct ubifs_info *c, int lnum, void **pbuf,
if (!sbuf)
return -ENOMEM;
- err = ubi_read(c->ubi, lnum, sbuf, 0, c->leb_size);
+ err = ubifs_leb_read(c, lnum, sbuf, 0, c->leb_size, 0);
if (err && err != -EBADMSG)
goto out_free;
@@ -175,10 +207,10 @@ static int write_rcvrd_mst_node(struct ubifs_info *c,
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);
+ err = ubifs_leb_change(c, lnum, mst, sz);
if (err)
goto out;
- err = ubi_leb_change(c->ubi, lnum + 1, mst, sz, UBI_SHORTTERM);
+ err = ubifs_leb_change(c, lnum + 1, mst, sz);
if (err)
goto out;
out:
@@ -236,7 +268,8 @@ int ubifs_recover_master_node(struct ubifs_info *c)
if (cor1)
goto out_err;
mst = mst1;
- } else if (offs1 == 0 && offs2 + sz >= c->leb_size) {
+ } else if (offs1 == 0 &&
+ c->leb_size - offs2 - sz < sz) {
/* 1st LEB was unmapped and written, 2nd not */
if (cor1)
goto out_err;
@@ -266,12 +299,12 @@ int ubifs_recover_master_node(struct ubifs_info *c)
mst = mst2;
}
- dbg_rcvry("recovered master node from LEB %d",
+ ubifs_msg("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)) {
+ if (c->ro_mount) {
/* Read-only mode. Keep a copy for switching to rw mode */
c->rcvrd_mst_node = kmalloc(sz, GFP_KERNEL);
if (!c->rcvrd_mst_node) {
@@ -279,6 +312,40 @@ int ubifs_recover_master_node(struct ubifs_info *c)
goto out_free;
}
memcpy(c->rcvrd_mst_node, c->mst_node, UBIFS_MST_NODE_SZ);
+
+ /*
+ * We had to recover the master node, which means there was an
+ * unclean reboot. However, it is possible that the master node
+ * is clean at this point, i.e., %UBIFS_MST_DIRTY is not set.
+ * E.g., consider the following chain of events:
+ *
+ * 1. UBIFS was cleanly unmounted, so the master node is clean
+ * 2. UBIFS is being mounted R/W and starts changing the master
+ * node in the first (%UBIFS_MST_LNUM). A power cut happens,
+ * so this LEB ends up with some amount of garbage at the
+ * end.
+ * 3. UBIFS is being mounted R/O. We reach this place and
+ * recover the master node from the second LEB
+ * (%UBIFS_MST_LNUM + 1). But we cannot update the media
+ * because we are being mounted R/O. We have to defer the
+ * operation.
+ * 4. However, this master node (@c->mst_node) is marked as
+ * clean (since the step 1). And if we just return, the
+ * mount code will be confused and won't recover the master
+ * node when it is re-mounter R/W later.
+ *
+ * Thus, to force the recovery by marking the master node as
+ * dirty.
+ */
+ c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
+#ifndef __UBOOT__
+ } else {
+ /* Write the recovered master node */
+ c->max_sqnum = le64_to_cpu(mst->ch.sqnum) - 1;
+ err = write_rcvrd_mst_node(c, c->mst_node);
+ if (err)
+ goto out_free;
+#endif
}
vfree(buf2);
@@ -291,12 +358,12 @@ out_err:
out_free:
ubifs_err("failed to recover master node");
if (mst1) {
- dbg_err("dumping first master node");
- dbg_dump_node(c, mst1);
+ ubifs_err("dumping first master node");
+ ubifs_dump_node(c, mst1);
}
if (mst2) {
- dbg_err("dumping second master node");
- dbg_dump_node(c, mst2);
+ ubifs_err("dumping second master node");
+ ubifs_dump_node(c, mst2);
}
vfree(buf2);
vfree(buf1);
@@ -335,44 +402,23 @@ int ubifs_write_rcvrd_mst_node(struct ubifs_info *c)
* @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).
+ * is in @buf, otherwise %0 is returned. The determination is made by checking
+ * for subsequent empty space starting from the next @c->max_write_size
+ * boundary.
*/
static int is_last_write(const struct ubifs_info *c, void *buf, int offs)
{
- int empty_offs;
- int check_len;
+ int empty_offs, 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.
+ * Round up to the next @c->max_write_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);
+ empty_offs = ALIGN(offs + 1, c->max_write_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;
+ return is_empty(p, check_len);
}
/**
@@ -385,7 +431,7 @@ static int is_last_write(const struct ubifs_info *c, void *buf, int offs)
*
* 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).
+ * @c->min_io_size boundary.
*/
static void clean_buf(const struct ubifs_info *c, void **buf, int lnum,
int *offs, int *len)
@@ -395,11 +441,6 @@ static void clean_buf(const struct ubifs_info *c, void **buf, int lnum,
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;
@@ -429,7 +470,7 @@ static int no_more_nodes(const struct ubifs_info *c, void *buf, int len,
int skip, dlen = le32_to_cpu(ch->len);
/* Check for empty space after the corrupt node's common header */
- skip = ALIGN(offs + UBIFS_CH_SZ, c->min_io_size) - offs;
+ skip = ALIGN(offs + UBIFS_CH_SZ, c->max_write_size) - offs;
if (is_empty(buf + skip, len - skip))
return 1;
/*
@@ -441,7 +482,7 @@ static int no_more_nodes(const struct ubifs_info *c, void *buf, int len,
return 0;
}
/* Now we know the corrupt node's length we can skip over it */
- skip = ALIGN(offs + dlen, c->min_io_size) - offs;
+ skip = ALIGN(offs + dlen, c->max_write_size) - offs;
/* After which there should be empty space */
if (is_empty(buf + skip, len - skip))
return 1;
@@ -469,7 +510,7 @@ static int fix_unclean_leb(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
endpt = snod->offs + snod->len;
}
- if ((c->vfs_sb->s_flags & MS_RDONLY) && !c->remounting_rw) {
+ if (c->ro_mount && !c->remounting_rw) {
/* Add to recovery list */
struct ubifs_unclean_leb *ucleb;
@@ -481,21 +522,55 @@ static int fix_unclean_leb(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
ucleb->lnum = lnum;
ucleb->endpt = endpt;
list_add_tail(&ucleb->list, &c->unclean_leb_list);
+#ifndef __UBOOT__
+ } else {
+ /* Write the fixed LEB back to flash */
+ int err;
+
+ dbg_rcvry("fixing LEB %d start %d endpt %d",
+ lnum, start, sleb->endpt);
+ if (endpt == 0) {
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ } else {
+ int len = ALIGN(endpt, c->min_io_size);
+
+ if (start) {
+ err = ubifs_leb_read(c, lnum, sleb->buf, 0,
+ start, 1);
+ if (err)
+ return err;
+ }
+ /* Pad to min_io_size */
+ if (len > endpt) {
+ int pad_len = len - ALIGN(endpt, 8);
+
+ if (pad_len > 0) {
+ void *buf = sleb->buf + len - pad_len;
+
+ ubifs_pad(c, buf, pad_len);
+ }
+ }
+ err = ubifs_leb_change(c, lnum, sleb->buf, len);
+ if (err)
+ return err;
+ }
+#endif
}
return 0;
}
/**
- * drop_incomplete_group - drop nodes from an incomplete group.
+ * drop_last_group - drop the last group of nodes.
* @sleb: scanned LEB information
* @offs: offset of dropped nodes is returned here
*
- * This function returns %1 if nodes are dropped and %0 otherwise.
+ * This is a helper function for 'ubifs_recover_leb()' which drops the last
+ * group of nodes of the scanned LEB.
*/
-static int drop_incomplete_group(struct ubifs_scan_leb *sleb, int *offs)
+static void drop_last_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;
@@ -504,15 +579,41 @@ static int drop_incomplete_group(struct ubifs_scan_leb *sleb, int *offs)
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);
+ break;
+
+ dbg_rcvry("dropping grouped node at %d:%d",
+ sleb->lnum, snod->offs);
+ *offs = snod->offs;
+ list_del(&snod->list);
+ kfree(snod);
+ sleb->nodes_cnt -= 1;
+ }
+}
+
+/**
+ * drop_last_node - drop the last node.
+ * @sleb: scanned LEB information
+ * @offs: offset of dropped nodes is returned here
+ * @grouped: non-zero if whole group of nodes have to be dropped
+ *
+ * This is a helper function for 'ubifs_recover_leb()' which drops the last
+ * node of the scanned LEB.
+ */
+static void drop_last_node(struct ubifs_scan_leb *sleb, int *offs)
+{
+ struct ubifs_scan_node *snod;
+
+ if (!list_empty(&sleb->nodes)) {
+ snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node,
+ list);
+
+ dbg_rcvry("dropping last 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;
}
/**
@@ -521,33 +622,30 @@ static int drop_incomplete_group(struct ubifs_scan_leb *sleb, int *offs)
* @lnum: LEB number
* @offs: offset
* @sbuf: LEB-sized buffer to use
- * @grouped: nodes may be grouped for recovery
+ * @jhead: journal head number this LEB belongs to (%-1 if the LEB does not
+ * belong to any journal head)
*
* 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.
+ * Returns %0 in case of success, %-EUCLEAN if an unrecoverable corruption is
+ * found, and a negative error code in case of failure.
*/
struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,
- int offs, void *sbuf, int grouped)
+ int offs, void *sbuf, int jhead)
{
- int err, len = c->leb_size - offs, need_clean = 0, quiet = 1;
- int empty_chkd = 0, start = offs;
+ int ret = 0, err, len = c->leb_size - offs, start = offs, min_io_unit;
+ int grouped = jhead == -1 ? 0 : c->jheads[jhead].grouped;
struct ubifs_scan_leb *sleb;
void *buf = sbuf + offs;
- dbg_rcvry("%d:%d", lnum, offs);
+ dbg_rcvry("%d:%d, jhead %d, grouped %d", lnum, offs, jhead, grouped);
sleb = ubifs_start_scan(c, lnum, offs, sbuf);
if (IS_ERR(sleb))
return sleb;
- if (sleb->ecc)
- need_clean = 1;
-
+ ubifs_assert(len >= 8);
while (len >= 8) {
- int ret;
-
dbg_scan("look at LEB %d:%d (%d bytes left)",
lnum, offs, len);
@@ -557,8 +655,7 @@ struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,
* Scan quietly until there is an error from which we cannot
* recover
*/
- ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet);
-
+ ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
if (ret == SCANNED_A_NODE) {
/* A valid node, and not a padding node */
struct ubifs_ch *ch = buf;
@@ -571,98 +668,127 @@ struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,
offs += node_len;
buf += node_len;
len -= node_len;
- continue;
- }
-
- if (ret > 0) {
+ } else 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;
+ } else if (ret == SCANNED_EMPTY_SPACE ||
+ ret == SCANNED_GARBAGE ||
+ ret == SCANNED_A_BAD_PAD_NODE ||
+ ret == SCANNED_A_CORRUPT_NODE) {
+ dbg_rcvry("found corruption (%d) at %d:%d",
+ ret, lnum, offs);
break;
+ } else {
+ ubifs_err("unexpected return value %d", ret);
+ err = -EINVAL;
+ goto error;
}
+ }
- 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;
- }
+ if (ret == SCANNED_GARBAGE || ret == SCANNED_A_BAD_PAD_NODE) {
+ if (!is_last_write(c, buf, offs))
+ goto corrupted_rescan;
+ } else if (ret == SCANNED_A_CORRUPT_NODE) {
+ if (!no_more_nodes(c, buf, len, lnum, offs))
+ goto corrupted_rescan;
+ } else if (!is_empty(buf, len)) {
+ if (!is_last_write(c, buf, offs)) {
+ int corruption = first_non_ff(buf, len);
- 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");
+ /*
+ * See header comment for this file for more
+ * explanations about the reasons we have this check.
+ */
+ ubifs_err("corrupt empty space LEB %d:%d, corruption starts at %d",
+ lnum, offs, corruption);
+ /* Make sure we dump interesting non-0xFF data */
+ offs += corruption;
+ buf += corruption;
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;
- }
- }
+ min_io_unit = round_down(offs, c->min_io_size);
+ if (grouped)
+ /*
+ * If nodes are grouped, always drop the incomplete group at
+ * the end.
+ */
+ drop_last_group(sleb, &offs);
- /* 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 (jhead == GCHD) {
+ /*
+ * If this LEB belongs to the GC head then while we are in the
+ * middle of the same min. I/O unit keep dropping nodes. So
+ * basically, what we want is to make sure that the last min.
+ * I/O unit where we saw the corruption is dropped completely
+ * with all the uncorrupted nodes which may possibly sit there.
+ *
+ * In other words, let's name the min. I/O unit where the
+ * corruption starts B, and the previous min. I/O unit A. The
+ * below code tries to deal with a situation when half of B
+ * contains valid nodes or the end of a valid node, and the
+ * second half of B contains corrupted data or garbage. This
+ * means that UBIFS had been writing to B just before the power
+ * cut happened. I do not know how realistic is this scenario
+ * that half of the min. I/O unit had been written successfully
+ * and the other half not, but this is possible in our 'failure
+ * mode emulation' infrastructure at least.
+ *
+ * So what is the problem, why we need to drop those nodes? Why
+ * can't we just clean-up the second half of B by putting a
+ * padding node there? We can, and this works fine with one
+ * exception which was reproduced with power cut emulation
+ * testing and happens extremely rarely.
+ *
+ * Imagine the file-system is full, we run GC which starts
+ * moving valid nodes from LEB X to LEB Y (obviously, LEB Y is
+ * the current GC head LEB). The @c->gc_lnum is -1, which means
+ * that GC will retain LEB X and will try to continue. Imagine
+ * that LEB X is currently the dirtiest LEB, and the amount of
+ * used space in LEB Y is exactly the same as amount of free
+ * space in LEB X.
+ *
+ * And a power cut happens when nodes are moved from LEB X to
+ * LEB Y. We are here trying to recover LEB Y which is the GC
+ * head LEB. We find the min. I/O unit B as described above.
+ * Then we clean-up LEB Y by padding min. I/O unit. And later
+ * 'ubifs_rcvry_gc_commit()' function fails, because it cannot
+ * find a dirty LEB which could be GC'd into LEB Y! Even LEB X
+ * does not match because the amount of valid nodes there does
+ * not fit the free space in LEB Y any more! And this is
+ * because of the padding node which we added to LEB Y. The
+ * user-visible effect of this which I once observed and
+ * analysed is that we cannot mount the file-system with
+ * -ENOSPC error.
+ *
+ * So obviously, to make sure that situation does not happen we
+ * should free min. I/O unit B in LEB Y completely and the last
+ * used min. I/O unit in LEB Y should be A. This is basically
+ * what the below code tries to do.
+ */
+ while (offs > min_io_unit)
+ drop_last_node(sleb, &offs);
}
- if (offs % c->min_io_size) {
- clean_buf(c, &buf, lnum, &offs, &len);
- need_clean = 1;
- }
+ buf = sbuf + offs;
+ len = c->leb_size - offs;
+ clean_buf(c, &buf, lnum, &offs, &len);
ubifs_end_scan(c, sleb, lnum, offs);
- if (need_clean) {
- err = fix_unclean_leb(c, sleb, start);
- if (err)
- goto error;
- }
+ err = fix_unclean_leb(c, sleb, start);
+ if (err)
+ goto error;
return sleb;
+corrupted_rescan:
+ /* Re-scan the corrupted data with verbose messages */
+ ubifs_err("corruption %d", ret);
+ ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
corrupted:
ubifs_scanned_corruption(c, lnum, offs, buf);
err = -EUCLEAN;
@@ -693,22 +819,23 @@ static int get_cs_sqnum(struct ubifs_info *c, int lnum, int offs,
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);
+ err = ubifs_leb_read(c, lnum, (void *)cs_node, offs,
+ UBIFS_CS_NODE_SZ, 0);
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");
+ ubifs_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);
+ ubifs_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);
+ ubifs_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);
@@ -732,7 +859,8 @@ out_free:
* @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.
+ * been caused by unclean reboots from which we are attempting to recover
+ * (assume that only the last log LEB can be corrupted by an unclean reboot).
*
* This function returns %0 on success and a negative error code on failure.
*/
@@ -751,7 +879,7 @@ struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int 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);
+ sleb = ubifs_scan(c, next_lnum, 0, sbuf, 0);
if (IS_ERR(sleb))
return sleb;
if (sleb->nodes_cnt) {
@@ -770,15 +898,15 @@ struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum,
}
}
if (snod->sqnum > cs_sqnum) {
- ubifs_err("unrecoverable log corruption "
- "in LEB %d", lnum);
+ 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);
+ return ubifs_recover_leb(c, lnum, offs, sbuf, -1);
}
/**
@@ -792,15 +920,10 @@ struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum,
*
* 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)
+static int recover_head(struct ubifs_info *c, int lnum, int offs, void *sbuf)
{
- int len, err, need_clean = 0;
+ int len = c->max_write_size, err;
- 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;
@@ -808,27 +931,15 @@ static int recover_head(const struct ubifs_info *c, int lnum, int offs,
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) {
+ err = ubifs_leb_read(c, lnum, sbuf, offs, len, 1);
+ if (err || !is_empty(sbuf, len)) {
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);
+ err = ubifs_leb_read(c, lnum, sbuf, 0, offs, 1);
if (err)
return err;
- return ubi_leb_change(c->ubi, lnum, sbuf, offs, UBI_UNKNOWN);
+ return ubifs_leb_change(c, lnum, sbuf, offs);
}
return 0;
@@ -851,11 +962,11 @@ static int recover_head(const struct ubifs_info *c, int lnum, int offs,
*
* 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 ubifs_recover_inl_heads(struct ubifs_info *c, void *sbuf)
{
int err;
- ubifs_assert(!(c->vfs_sb->s_flags & MS_RDONLY) || c->remounting_rw);
+ ubifs_assert(!c->ro_mount || 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);
@@ -871,7 +982,7 @@ int ubifs_recover_inl_heads(const struct ubifs_info *c, void *sbuf)
}
/**
- * clean_an_unclean_leb - read and write a LEB to remove corruption.
+ * 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
@@ -882,7 +993,7 @@ int ubifs_recover_inl_heads(const struct ubifs_info *c, void *sbuf)
*
* This function returns %0 on success and a negative error code on failure.
*/
-static int clean_an_unclean_leb(const struct ubifs_info *c,
+static int clean_an_unclean_leb(struct ubifs_info *c,
struct ubifs_unclean_leb *ucleb, void *sbuf)
{
int err, lnum = ucleb->lnum, offs = 0, len = ucleb->endpt, quiet = 1;
@@ -898,7 +1009,7 @@ static int clean_an_unclean_leb(const struct ubifs_info *c,
return 0;
}
- err = ubi_read(c->ubi, lnum, buf, offs, len);
+ err = ubifs_leb_read(c, lnum, buf, offs, len, 0);
if (err && err != -EBADMSG)
return err;
@@ -958,7 +1069,7 @@ static int clean_an_unclean_leb(const struct ubifs_info *c,
}
/* Write back the LEB atomically */
- err = ubi_leb_change(c->ubi, lnum, sbuf, len, UBI_UNKNOWN);
+ err = ubifs_leb_change(c, lnum, sbuf, len);
if (err)
return err;
@@ -978,7 +1089,7 @@ static int clean_an_unclean_leb(const struct ubifs_info *c,
*
* This function returns %0 on success and a negative error code on failure.
*/
-int ubifs_clean_lebs(const struct ubifs_info *c, void *sbuf)
+int ubifs_clean_lebs(struct ubifs_info *c, void *sbuf)
{
dbg_rcvry("recovery");
while (!list_empty(&c->unclean_leb_list)) {
@@ -996,6 +1107,140 @@ int ubifs_clean_lebs(const struct ubifs_info *c, void *sbuf)
return 0;
}
+#ifndef __UBOOT__
+/**
+ * grab_empty_leb - grab an empty LEB to use as GC LEB and run commit.
+ * @c: UBIFS file-system description object
+ *
+ * This is a helper function for 'ubifs_rcvry_gc_commit()' which grabs an empty
+ * LEB to be used as GC LEB (@c->gc_lnum), and then runs the commit. Returns
+ * zero in case of success and a negative error code in case of failure.
+ */
+static int grab_empty_leb(struct ubifs_info *c)
+{
+ int lnum, err;
+
+ /*
+ * Note, it is very important to first search for an empty LEB and then
+ * run the commit, not vice-versa. The reason is that there might be
+ * only one empty LEB at the moment, the one which has been the
+ * @c->gc_lnum just before the power cut happened. During the regular
+ * UBIFS operation (not now) @c->gc_lnum is marked as "taken", so no
+ * one but GC can grab it. But at this moment this single empty LEB is
+ * not marked as taken, so if we run commit - what happens? Right, the
+ * commit will grab it and write the index there. Remember that the
+ * index always expands as long as there is free space, and it only
+ * starts consolidating when we run out of space.
+ *
+ * IOW, if we run commit now, we might not be able to find a free LEB
+ * after this.
+ */
+ lnum = ubifs_find_free_leb_for_idx(c);
+ if (lnum < 0) {
+ ubifs_err("could not find an empty LEB");
+ ubifs_dump_lprops(c);
+ ubifs_dump_budg(c, &c->bi);
+ return lnum;
+ }
+
+ /* Reset the index flag */
+ err = ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,
+ LPROPS_INDEX, 0);
+ if (err)
+ return err;
+
+ c->gc_lnum = lnum;
+ dbg_rcvry("found empty LEB %d, run commit", lnum);
+
+ return ubifs_run_commit(c);
+}
+
+/**
+ * ubifs_rcvry_gc_commit - recover the GC LEB number and run the commit.
+ * @c: UBIFS file-system description object
+ *
+ * Out-of-place garbage collection requires always one empty LEB with which to
+ * start garbage collection. The LEB number is recorded in c->gc_lnum and is
+ * written to the master node on unmounting. In the case of an unclean unmount
+ * the value of gc_lnum recorded in the master node is out of date and cannot
+ * be used. Instead, recovery must allocate an empty LEB for this purpose.
+ * However, there may not be enough empty space, in which case it must be
+ * possible to GC the dirtiest LEB into the GC head LEB.
+ *
+ * This function also runs the commit which causes the TNC updates from
+ * size-recovery and orphans to be written to the flash. That is important to
+ * ensure correct replay order for subsequent mounts.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_rcvry_gc_commit(struct ubifs_info *c)
+{
+ struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
+ struct ubifs_lprops lp;
+ int err;
+
+ dbg_rcvry("GC head LEB %d, offs %d", wbuf->lnum, wbuf->offs);
+
+ c->gc_lnum = -1;
+ if (wbuf->lnum == -1 || wbuf->offs == c->leb_size)
+ return grab_empty_leb(c);
+
+ err = ubifs_find_dirty_leb(c, &lp, wbuf->offs, 2);
+ if (err) {
+ if (err != -ENOSPC)
+ return err;
+
+ dbg_rcvry("could not find a dirty LEB");
+ return grab_empty_leb(c);
+ }
+
+ ubifs_assert(!(lp.flags & LPROPS_INDEX));
+ ubifs_assert(lp.free + lp.dirty >= wbuf->offs);
+
+ /*
+ * We run the commit before garbage collection otherwise subsequent
+ * mounts will see the GC and orphan deletion in a different order.
+ */
+ dbg_rcvry("committing");
+ err = ubifs_run_commit(c);
+ if (err)
+ return err;
+
+ dbg_rcvry("GC'ing LEB %d", lp.lnum);
+ mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+ err = ubifs_garbage_collect_leb(c, &lp);
+ if (err >= 0) {
+ int err2 = ubifs_wbuf_sync_nolock(wbuf);
+
+ if (err2)
+ err = err2;
+ }
+ mutex_unlock(&wbuf->io_mutex);
+ if (err < 0) {
+ ubifs_err("GC failed, error %d", err);
+ if (err == -EAGAIN)
+ err = -EINVAL;
+ return err;
+ }
+
+ ubifs_assert(err == LEB_RETAINED);
+ if (err != LEB_RETAINED)
+ return -EINVAL;
+
+ err = ubifs_leb_unmap(c, c->gc_lnum);
+ if (err)
+ return err;
+
+ dbg_rcvry("allocated LEB %d for GC", lp.lnum);
+ return 0;
+}
+#else
+int ubifs_rcvry_gc_commit(struct ubifs_info *c)
+{
+ return 0;
+}
+#endif
+
/**
* struct size_entry - inode size information for recovery.
* @rb: link in the RB-tree of sizes
@@ -1090,6 +1335,23 @@ static void remove_ino(struct ubifs_info *c, ino_t inum)
}
/**
+ * ubifs_destroy_size_tree - free resources related to the size tree.
+ * @c: UBIFS file-system description object
+ */
+void ubifs_destroy_size_tree(struct ubifs_info *c)
+{
+ struct size_entry *e, *n;
+
+ rbtree_postorder_for_each_entry_safe(e, n, &c->size_tree, rb) {
+ if (e->inode)
+ iput(e->inode);
+ kfree(e);
+ }
+
+ c->size_tree = RB_ROOT;
+}
+
+/**
* ubifs_recover_size_accum - accumulate inode sizes for recovery.
* @c: UBIFS file-system description object
* @key: node key
@@ -1157,6 +1419,64 @@ int ubifs_recover_size_accum(struct ubifs_info *c, union ubifs_key *key,
return 0;
}
+#ifndef __UBOOT__
+/**
+ * fix_size_in_place - fix inode size in place on flash.
+ * @c: UBIFS file-system description object
+ * @e: inode size information for recovery
+ */
+static int fix_size_in_place(struct ubifs_info *c, struct size_entry *e)
+{
+ struct ubifs_ino_node *ino = c->sbuf;
+ unsigned char *p;
+ union ubifs_key key;
+ int err, lnum, offs, len;
+ loff_t i_size;
+ uint32_t crc;
+
+ /* Locate the inode node LEB number and offset */
+ ino_key_init(c, &key, e->inum);
+ err = ubifs_tnc_locate(c, &key, ino, &lnum, &offs);
+ if (err)
+ goto out;
+ /*
+ * If the size recorded on the inode node is greater than the size that
+ * was calculated from nodes in the journal then don't change the inode.
+ */
+ i_size = le64_to_cpu(ino->size);
+ if (i_size >= e->d_size)
+ return 0;
+ /* Read the LEB */
+ err = ubifs_leb_read(c, lnum, c->sbuf, 0, c->leb_size, 1);
+ if (err)
+ goto out;
+ /* Change the size field and recalculate the CRC */
+ ino = c->sbuf + offs;
+ ino->size = cpu_to_le64(e->d_size);
+ len = le32_to_cpu(ino->ch.len);
+ crc = crc32(UBIFS_CRC32_INIT, (void *)ino + 8, len - 8);
+ ino->ch.crc = cpu_to_le32(crc);
+ /* Work out where data in the LEB ends and free space begins */
+ p = c->sbuf;
+ len = c->leb_size - 1;
+ while (p[len] == 0xff)
+ len -= 1;
+ len = ALIGN(len + 1, c->min_io_size);
+ /* Atomically write the fixed LEB back again */
+ err = ubifs_leb_change(c, lnum, c->sbuf, len);
+ if (err)
+ goto out;
+ dbg_rcvry("inode %lu at %d:%d size %lld -> %lld",
+ (unsigned long)e->inum, lnum, offs, i_size, e->d_size);
+ return 0;
+
+out:
+ ubifs_warn("inode %lu failed to fix size %lld -> %lld error %d",
+ (unsigned long)e->inum, e->i_size, e->d_size, err);
+ return err;
+}
+#endif
+
/**
* ubifs_recover_size - recover inode size.
* @c: UBIFS file-system description object
@@ -1196,30 +1516,48 @@ int ubifs_recover_size(struct ubifs_info *c)
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)) {
+ if (c->ro_mount) {
/* Fix the inode size and pin it in memory */
struct inode *inode;
+ struct ubifs_inode *ui;
+
+ ubifs_assert(!e->inode);
inode = ubifs_iget(c->vfs_sb, e->inum);
if (IS_ERR(inode))
return PTR_ERR(inode);
+
+ ui = ubifs_inode(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);
inode->i_size = e->d_size;
- ubifs_inode(inode)->ui_size = e->d_size;
+ ui->ui_size = e->d_size;
+ ui->synced_i_size = e->d_size;
e->inode = inode;
this = rb_next(this);
continue;
}
iput(inode);
+#ifndef __UBOOT__
+ } else {
+ /* Fix the size in place */
+ err = fix_size_in_place(c, e);
+ if (err)
+ return err;
+ if (e->inode)
+ iput(e->inode);
+#endif
}
}
+
this = rb_next(this);
rb_erase(&e->rb, &c->size_tree);
kfree(e);
}
+
return 0;
}