diff options
Diffstat (limited to 'drivers/mtd/ubi')
| -rw-r--r-- | drivers/mtd/ubi/io.c | 1274 | ||||
| -rw-r--r-- | drivers/mtd/ubi/kapi.c | 638 | ||||
| -rw-r--r-- | drivers/mtd/ubi/misc.c | 106 |
3 files changed, 2018 insertions, 0 deletions
diff --git a/drivers/mtd/ubi/io.c b/drivers/mtd/ubi/io.c new file mode 100644 index 0000000..2d44f23 --- /dev/null +++ b/drivers/mtd/ubi/io.c @@ -0,0 +1,1274 @@ +/* + * Copyright (c) International Business Machines Corp., 2006 + * Copyright (c) Nokia Corporation, 2006, 2007 + * + * 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 + * + * Author: Artem Bityutskiy (Битюцкий Артём) + */ + +/* + * UBI input/output unit. + * + * This unit provides a uniform way to work with all kinds of the underlying + * MTD devices. It also implements handy functions for reading and writing UBI + * headers. + * + * We are trying to have a paranoid mindset and not to trust to what we read + * from the flash media in order to be more secure and robust. So this unit + * validates every single header it reads from the flash media. + * + * Some words about how the eraseblock headers are stored. + * + * The erase counter header is always stored at offset zero. By default, the + * VID header is stored after the EC header at the closest aligned offset + * (i.e. aligned to the minimum I/O unit size). Data starts next to the VID + * header at the closest aligned offset. But this default layout may be + * changed. For example, for different reasons (e.g., optimization) UBI may be + * asked to put the VID header at further offset, and even at an unaligned + * offset. Of course, if the offset of the VID header is unaligned, UBI adds + * proper padding in front of it. Data offset may also be changed but it has to + * be aligned. + * + * About minimal I/O units. In general, UBI assumes flash device model where + * there is only one minimal I/O unit size. E.g., in case of NOR flash it is 1, + * in case of NAND flash it is a NAND page, etc. This is reported by MTD in the + * @ubi->mtd->writesize field. But as an exception, UBI admits of using another + * (smaller) minimal I/O unit size for EC and VID headers to make it possible + * to do different optimizations. + * + * This is extremely useful in case of NAND flashes which admit of several + * write operations to one NAND page. In this case UBI can fit EC and VID + * headers at one NAND page. Thus, UBI may use "sub-page" size as the minimal + * I/O unit for the headers (the @ubi->hdrs_min_io_size field). But it still + * reports NAND page size (@ubi->min_io_size) as a minimal I/O unit for the UBI + * users. + * + * Example: some Samsung NANDs with 2KiB pages allow 4x 512-byte writes, so + * although the minimal I/O unit is 2K, UBI uses 512 bytes for EC and VID + * headers. + * + * Q: why not just to treat sub-page as a minimal I/O unit of this flash + * device, e.g., make @ubi->min_io_size = 512 in the example above? + * + * A: because when writing a sub-page, MTD still writes a full 2K page but the + * bytes which are no relevant to the sub-page are 0xFF. So, basically, writing + * 4x512 sub-pages is 4 times slower then writing one 2KiB NAND page. Thus, we + * prefer to use sub-pages only for EV and VID headers. + * + * As it was noted above, the VID header may start at a non-aligned offset. + * For example, in case of a 2KiB page NAND flash with a 512 bytes sub-page, + * the VID header may reside at offset 1984 which is the last 64 bytes of the + * last sub-page (EC header is always at offset zero). This causes some + * difficulties when reading and writing VID headers. + * + * Suppose we have a 64-byte buffer and we read a VID header at it. We change + * the data and want to write this VID header out. As we can only write in + * 512-byte chunks, we have to allocate one more buffer and copy our VID header + * to offset 448 of this buffer. + * + * The I/O unit does the following trick in order to avoid this extra copy. + * It always allocates a @ubi->vid_hdr_alsize bytes buffer for the VID header + * and returns a pointer to offset @ubi->vid_hdr_shift of this buffer. When the + * VID header is being written out, it shifts the VID header pointer back and + * writes the whole sub-page. + */ + +#ifdef UBI_LINUX +#include <linux/crc32.h> +#include <linux/err.h> +#endif + +#include <ubi_uboot.h> +#include "ubi.h" + +#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID +static int paranoid_check_not_bad(const struct ubi_device *ubi, int pnum); +static int paranoid_check_peb_ec_hdr(const struct ubi_device *ubi, int pnum); +static int paranoid_check_ec_hdr(const struct ubi_device *ubi, int pnum, + const struct ubi_ec_hdr *ec_hdr); +static int paranoid_check_peb_vid_hdr(const struct ubi_device *ubi, int pnum); +static int paranoid_check_vid_hdr(const struct ubi_device *ubi, int pnum, + const struct ubi_vid_hdr *vid_hdr); +static int paranoid_check_all_ff(struct ubi_device *ubi, int pnum, int offset, + int len); +#else +#define paranoid_check_not_bad(ubi, pnum) 0 +#define paranoid_check_peb_ec_hdr(ubi, pnum) 0 +#define paranoid_check_ec_hdr(ubi, pnum, ec_hdr) 0 +#define paranoid_check_peb_vid_hdr(ubi, pnum) 0 +#define paranoid_check_vid_hdr(ubi, pnum, vid_hdr) 0 +#define paranoid_check_all_ff(ubi, pnum, offset, len) 0 +#endif + +/** + * ubi_io_read - read data from a physical eraseblock. + * @ubi: UBI device description object + * @buf: buffer where to store the read data + * @pnum: physical eraseblock number to read from + * @offset: offset within the physical eraseblock from where to read + * @len: how many bytes to read + * + * This function reads data from offset @offset of physical eraseblock @pnum + * and stores the read data in the @buf buffer. The following return codes are + * possible: + * + * o %0 if all the requested data were successfully read; + * o %UBI_IO_BITFLIPS if all the requested data were successfully read, but + * correctable bit-flips were detected; this is harmless but may indicate + * that this eraseblock may become bad soon (but do not have to); + * o %-EBADMSG if the MTD subsystem reported about data integrity problems, for + * example it can be an ECC error in case of NAND; this most probably means + * that the data is corrupted; + * o %-EIO if some I/O error occurred; + * o other negative error codes in case of other errors. + */ +int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset, + int len) +{ + int err, retries = 0; + size_t read; + loff_t addr; + + dbg_io("read %d bytes from PEB %d:%d", len, pnum, offset); + + ubi_assert(pnum >= 0 && pnum < ubi->peb_count); + ubi_assert(offset >= 0 && offset + len <= ubi->peb_size); + ubi_assert(len > 0); + + err = paranoid_check_not_bad(ubi, pnum); + if (err) + return err > 0 ? -EINVAL : err; + + addr = (loff_t)pnum * ubi->peb_size + offset; +retry: + err = ubi->mtd->read(ubi->mtd, addr, len, &read, buf); + if (err) { + if (err == -EUCLEAN) { + /* + * -EUCLEAN is reported if there was a bit-flip which + * was corrected, so this is harmless. + */ + ubi_msg("fixable bit-flip detected at PEB %d", pnum); + ubi_assert(len == read); + return UBI_IO_BITFLIPS; + } + + if (read != len && retries++ < UBI_IO_RETRIES) { + dbg_io("error %d while reading %d bytes from PEB %d:%d, " + "read only %zd bytes, retry", + err, len, pnum, offset, read); + yield(); + goto retry; + } + + ubi_err("error %d while reading %d bytes from PEB %d:%d, " + "read %zd bytes", err, len, pnum, offset, read); + ubi_dbg_dump_stack(); + + /* + * The driver should never return -EBADMSG if it failed to read + * all the requested data. But some buggy drivers might do + * this, so we change it to -EIO. + */ + if (read != len && err == -EBADMSG) { + ubi_assert(0); + printk("%s[%d] not here\n", __func__, __LINE__); +// err = -EIO; + } + } else { + ubi_assert(len == read); + + if (ubi_dbg_is_bitflip()) { + dbg_msg("bit-flip (emulated)"); + err = UBI_IO_BITFLIPS; + } + } + + return err; +} + +/** + * ubi_io_write - write data to a physical eraseblock. + * @ubi: UBI device description object + * @buf: buffer with the data to write + * @pnum: physical eraseblock number to write to + * @offset: offset within the physical eraseblock where to write + * @len: how many bytes to write + * + * This function writes @len bytes of data from buffer @buf to offset @offset + * of physical eraseblock @pnum. If all the data were successfully written, + * zero is returned. If an error occurred, this function returns a negative + * error code. If %-EIO is returned, the physical eraseblock most probably went + * bad. + * + * Note, in case of an error, it is possible that something was still written + * to the flash media, but may be some garbage. + */ +int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset, + int len) +{ + int err; + size_t written; + loff_t addr; + + dbg_io("write %d bytes to PEB %d:%d", len, pnum, offset); + + ubi_assert(pnum >= 0 && pnum < ubi->peb_count); + ubi_assert(offset >= 0 && offset + len <= ubi->peb_size); + ubi_assert(offset % ubi->hdrs_min_io_size == 0); + ubi_assert(len > 0 && len % ubi->hdrs_min_io_size == 0); + + if (ubi->ro_mode) { + ubi_err("read-only mode"); + return -EROFS; + } + + /* The below has to be compiled out if paranoid checks are disabled */ + + err = paranoid_check_not_bad(ubi, pnum); + if (err) + return err > 0 ? -EINVAL : err; + + /* The area we are writing to has to contain all 0xFF bytes */ + err = paranoid_check_all_ff(ubi, pnum, offset, len); + if (err) + return err > 0 ? -EINVAL : err; + + if (offset >= ubi->leb_start) { + /* + * We write to the data area of the physical eraseblock. Make + * sure it has valid EC and VID headers. + */ + err = paranoid_check_peb_ec_hdr(ubi, pnum); + if (err) + return err > 0 ? -EINVAL : err; + err = paranoid_check_peb_vid_hdr(ubi, pnum); + if (err) + return err > 0 ? -EINVAL : err; + } + + if (ubi_dbg_is_write_failure()) { + dbg_err("cannot write %d bytes to PEB %d:%d " + "(emulated)", len, pnum, offset); + ubi_dbg_dump_stack(); + return -EIO; + } + + addr = (loff_t)pnum * ubi->peb_size + offset; + err = ubi->mtd->write(ubi->mtd, addr, len, &written, buf); + if (err) { + ubi_err("error %d while writing %d bytes to PEB %d:%d, written" + " %zd bytes", err, len, pnum, offset, written); + ubi_dbg_dump_stack(); + } else + ubi_assert(written == len); + + return err; +} + +/** + * erase_callback - MTD erasure call-back. + * @ei: MTD erase information object. + * + * Note, even though MTD erase interface is asynchronous, all the current + * implementations are synchronous anyway. + */ +static void erase_callback(struct erase_info *ei) +{ + wake_up_interruptible((wait_queue_head_t *)ei->priv); +} + +/** + * do_sync_erase - synchronously erase a physical eraseblock. + * @ubi: UBI device description object + * @pnum: the physical eraseblock number to erase + * + * This function synchronously erases physical eraseblock @pnum and returns + * zero in case of success and a negative error code in case of failure. If + * %-EIO is returned, the physical eraseblock most probably went bad. + */ +static int do_sync_erase(struct ubi_device *ubi, int pnum) +{ + int err, retries = 0; + struct erase_info ei; + wait_queue_head_t wq; + + dbg_io("erase PEB %d", pnum); + +retry: + init_waitqueue_head(&wq); + memset(&ei, 0, sizeof(struct erase_info)); + + ei.mtd = ubi->mtd; + ei.addr = (loff_t)pnum * ubi->peb_size; + ei.len = ubi->peb_size; + ei.callback = erase_callback; + ei.priv = (unsigned long)&wq; + + err = ubi->mtd->erase(ubi->mtd, &ei); + if (err) { + if (retries++ < UBI_IO_RETRIES) { + dbg_io("error %d while erasing PEB %d, retry", + err, pnum); + yield(); + goto retry; + } + ubi_err("cannot erase PEB %d, error %d", pnum, err); + ubi_dbg_dump_stack(); + return err; + } + + err = wait_event_interruptible(wq, ei.state == MTD_ERASE_DONE || + ei.state == MTD_ERASE_FAILED); + if (err) { + ubi_err("interrupted PEB %d erasure", pnum); + return -EINTR; + } + + if (ei.state == MTD_ERASE_FAILED) { + if (retries++ < UBI_IO_RETRIES) { + dbg_io("error while erasing PEB %d, retry", pnum); + yield(); + goto retry; + } + ubi_err("cannot erase PEB %d", pnum); + ubi_dbg_dump_stack(); + return -EIO; + } + + err = paranoid_check_all_ff(ubi, pnum, 0, ubi->peb_size); + if (err) + return err > 0 ? -EINVAL : err; + + if (ubi_dbg_is_erase_failure() && !err) { + dbg_err("cannot erase PEB %d (emulated)", pnum); + return -EIO; + } + + return 0; +} + +/** + * check_pattern - check if buffer contains only a certain byte pattern. + * @buf: buffer to check + * @patt: the pattern to check + * @size: buffer size in bytes + * + * This function returns %1 in there are only @patt bytes in @buf, and %0 if + * something else was also found. + */ +static int check_pattern(const void *buf, uint8_t patt, int size) +{ + int i; + + for (i = 0; i < size; i++) + if (((const uint8_t *)buf)[i] != patt) + return 0; + return 1; +} + +/* Patterns to write to a physical eraseblock when torturing it */ +static uint8_t patterns[] = {0xa5, 0x5a, 0x0}; + +/** + * torture_peb - test a supposedly bad physical eraseblock. + * @ubi: UBI device description object + * @pnum: the physical eraseblock number to test + * + * This function returns %-EIO if the physical eraseblock did not pass the + * test, a positive number of erase operations done if the test was + * successfully passed, and other negative error codes in case of other errors. + */ +static int torture_peb(struct ubi_device *ubi, int pnum) +{ + int err, i, patt_count; + + patt_count = ARRAY_SIZE(patterns); + ubi_assert(patt_count > 0); + + mutex_lock(&ubi->buf_mutex); + for (i = 0; i < patt_count; i++) { + err = do_sync_erase(ubi, pnum); + if (err) + goto out; + + /* Make sure the PEB contains only 0xFF bytes */ + err = ubi_io_read(ubi, ubi->peb_buf1, pnum, 0, ubi->peb_size); + if (err) + goto out; + + err = check_pattern(ubi->peb_buf1, 0xFF, ubi->peb_size); + if (err == 0) { + ubi_err("erased PEB %d, but a non-0xFF byte found", + pnum); + err = -EIO; + goto out; + } + + /* Write a pattern and check it */ + memset(ubi->peb_buf1, patterns[i], ubi->peb_size); + err = ubi_io_write(ubi, ubi->peb_buf1, pnum, 0, ubi->peb_size); + if (err) + goto out; + + memset(ubi->peb_buf1, ~patterns[i], ubi->peb_size); + err = ubi_io_read(ubi, ubi->peb_buf1, pnum, 0, ubi->peb_size); + if (err) + goto out; + + err = check_pattern(ubi->peb_buf1, patterns[i], ubi->peb_size); + if (err == 0) { + ubi_err("pattern %x checking failed for PEB %d", + patterns[i], pnum); + err = -EIO; + goto out; + } + } + + err = patt_count; + +out: + mutex_unlock(&ubi->buf_mutex); + if (err == UBI_IO_BITFLIPS || err == -EBADMSG) { + /* + * If a bit-flip or data integrity error was detected, the test + * has not passed because it happened on a freshly erased + * physical eraseblock which means something is wrong with it. + */ + ubi_err("read problems on freshly erased PEB %d, must be bad", + pnum); + err = -EIO; + } + return err; +} + +/** + * ubi_io_sync_erase - synchronously erase a physical eraseblock. + * @ubi: UBI device description object + * @pnum: physical eraseblock number to erase + * @torture: if this physical eraseblock has to be tortured + * + * This function synchronously erases physical eraseblock @pnum. If @torture + * flag is not zero, the physical eraseblock is checked by means of writing + * different patterns to it and reading them back. If the torturing is enabled, + * the physical eraseblock is erased more then once. + * + * This function returns the number of erasures made in case of success, %-EIO + * if the erasure failed or the torturing test failed, and other negative error + * codes in case of other errors. Note, %-EIO means that the physical + * eraseblock is bad. + */ +int ubi_io_sync_erase(struct ubi_device *ubi, int pnum, int torture) +{ + int err, ret = 0; + + ubi_assert(pnum >= 0 && pnum < ubi->peb_count); + + err = paranoid_check_not_bad(ubi, pnum); + if (err != 0) + return err > 0 ? -EINVAL : err; + + if (ubi->ro_mode) { + ubi_err("read-only mode"); + return -EROFS; + } + + if (torture) { + ret = torture_peb(ubi, pnum); + if (ret < 0) + return ret; + } + + err = do_sync_erase(ubi, pnum); + if (err) + return err; + + return ret + 1; +} + +/** + * ubi_io_is_bad - check if a physical eraseblock is bad. + * @ubi: UBI device description object + * @pnum: the physical eraseblock number to check + * + * This function returns a positive number if the physical eraseblock is bad, + * zero if not, and a negative error code if an error occurred. + */ +int ubi_io_is_bad(const struct ubi_device *ubi, int pnum) +{ + struct mtd_info *mtd = ubi->mtd; + + ubi_assert(pnum >= 0 && pnum < ubi->peb_count); + + if (ubi->bad_allowed) { + int ret; + + ret = mtd->block_isbad(mtd, (loff_t)pnum * ubi->peb_size); + if (ret < 0) + ubi_err("error %d while checking if PEB %d is bad", + ret, pnum); + else if (ret) + dbg_io("PEB %d is bad", pnum); + return ret; + } + + return 0; +} + +/** + * ubi_io_mark_bad - mark a physical eraseblock as bad. + * @ubi: UBI device description object + * @pnum: the physical eraseblock number to mark + * + * This function returns zero in case of success and a negative error code in + * case of failure. + */ +int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum) +{ + int err; + struct mtd_info *mtd = ubi->mtd; + + ubi_assert(pnum >= 0 && pnum < ubi->peb_count); + + if (ubi->ro_mode) { + ubi_err("read-only mode"); + return -EROFS; + } + + if (!ubi->bad_allowed) + return 0; + + err = mtd->block_markbad(mtd, (loff_t)pnum * ubi->peb_size); + if (err) + ubi_err("cannot mark PEB %d bad, error %d", pnum, err); + return err; +} + +/** + * validate_ec_hdr - validate an erase counter header. + * @ubi: UBI device description object + * @ec_hdr: the erase counter header to check + * + * This function returns zero if the erase counter header is OK, and %1 if + * not. + */ +static int validate_ec_hdr(const struct ubi_device *ubi, + const struct ubi_ec_hdr *ec_hdr) +{ + long long ec; + int vid_hdr_offset, leb_start; + + ec = be64_to_cpu(ec_hdr->ec); + vid_hdr_offset = be32_to_cpu(ec_hdr->vid_hdr_offset); + leb_start = be32_to_cpu(ec_hdr->data_offset); + + if (ec_hdr->version != UBI_VERSION) { + ubi_err("node with incompatible UBI version found: " + "this UBI version is %d, image version is %d", + UBI_VERSION, (int)ec_hdr->version); + goto bad; + } + + if (vid_hdr_offset != ubi->vid_hdr_offset) { + ubi_err("bad VID header offset %d, expected %d", + vid_hdr_offset, ubi->vid_hdr_offset); + goto bad; + } + + if (leb_start != ubi->leb_start) { + ubi_err("bad data offset %d, expected %d", + leb_start, ubi->leb_start); + goto bad; + } + + if (ec < 0 || ec > UBI_MAX_ERASECOUNTER) { + ubi_err("bad erase counter %lld", ec); + goto bad; + } + + return 0; + +bad: + ubi_err("bad EC header"); + ubi_dbg_dump_ec_hdr(ec_hdr); + ubi_dbg_dump_stack(); + return 1; +} + +/** + * ubi_io_read_ec_hdr - read and check an erase counter header. + * @ubi: UBI device description object + * @pnum: physical eraseblock to read from + * @ec_hdr: a &struct ubi_ec_hdr object where to store the read erase counter + * header + * @verbose: be verbose if the header is corrupted or was not found + * + * This function reads erase counter header from physical eraseblock @pnum and + * stores it in @ec_hdr. This function also checks CRC checksum of the read + * erase counter header. The following codes may be returned: + * + * o %0 if the CRC checksum is correct and the header was successfully read; + * o %UBI_IO_BITFLIPS if the CRC is correct, but bit-flips were detected + * and corrected by the flash driver; this is harmless but may indicate that + * this eraseblock may become bad soon (but may be not); + * o %UBI_IO_BAD_EC_HDR if the erase counter header is corrupted (a CRC error); + * o %UBI_IO_PEB_EMPTY if the physical eraseblock is empty; + * o a negative error code in case of failure. + */ +int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum, + struct ubi_ec_hdr *ec_hdr, int verbose) +{ + int err, read_err = 0; + uint32_t crc, magic, hdr_crc; + + dbg_io("read EC header from PEB %d", pnum); + ubi_assert(pnum >= 0 && pnum < ubi->peb_count); + if (UBI_IO_DEBUG) + verbose = 1; + + err = ubi_io_read(ubi, ec_hdr, pnum, 0, UBI_EC_HDR_SIZE); + if (err) { + if (err != UBI_IO_BITFLIPS && err != -EBADMSG) + return err; + + /* + * We read all the data, but either a correctable bit-flip + * occurred, or MTD reported about some data integrity error, + * like an ECC error in case of NAND. The former is harmless, + * the later may mean that the read data is corrupted. But we + * have a CRC check-sum and we will detect this. If the EC + * header is still OK, we just report this as there was a + * bit-flip. + */ + read_err = err; + } + + magic = be32_to_cpu(ec_hdr->magic); + if (magic != UBI_EC_HDR_MAGIC) { + /* + * The magic field is wrong. Let's check if we have read all + * 0xFF. If yes, this physical eraseblock is assumed to be + * empty. + * + * But if there was a read error, we do not test it for all + * 0xFFs. Even if it does contain all 0xFFs, this error + * indicates that something is still wrong with this physical + * eraseblock and we anyway cannot treat it as empty. + */ + if (read_err != -EBADMSG && + check_pattern(ec_hdr, 0xFF, UBI_EC_HDR_SIZE)) { + /* The physical eraseblock is supposedly empty */ + + /* + * The below is just a paranoid check, it has to be + * compiled out if paranoid checks are disabled. + */ + err = paranoid_check_all_ff(ubi, pnum, 0, + ubi->peb_size); + if (err) + return err > 0 ? UBI_IO_BAD_EC_HDR : err; + + if (verbose) + ubi_warn("no EC header found at PEB %d, " + "only 0xFF bytes", pnum); + return UBI_IO_PEB_EMPTY; + } + + /* + * This is not a valid erase counter header, and these are not + * 0xFF bytes. Report that the header is corrupted. + */ + if (verbose) { + ubi_warn("bad magic number at PEB %d: %08x instead of " + "%08x", pnum, magic, UBI_EC_HDR_MAGIC); + ubi_dbg_dump_ec_hdr(ec_hdr); + } + return UBI_IO_BAD_EC_HDR; + } + + crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC); + hdr_crc = be32_to_cpu(ec_hdr->hdr_crc); + + if (hdr_crc != crc) { + if (verbose) { + ubi_warn("bad EC header CRC at PEB %d, calculated %#08x," + " read %#08x", pnum, crc, hdr_crc); + ubi_dbg_dump_ec_hdr(ec_hdr); + } + return UBI_IO_BAD_EC_HDR; + } + + /* And of course validate what has just been read from the media */ + err = validate_ec_hdr(ubi, ec_hdr); + if (err) { + ubi_err("validation failed for PEB %d", pnum); + return -EINVAL; + } + + return read_err ? UBI_IO_BITFLIPS : 0; +} + +/** + * ubi_io_write_ec_hdr - write an erase counter header. + * @ubi: UBI device description object + * @pnum: physical eraseblock to write to + * @ec_hdr: the erase counter header to write + * + * This function writes erase counter header described by @ec_hdr to physical + * eraseblock @pnum. It also fills most fields of @ec_hdr before writing, so + * the caller do not have to fill them. Callers must only fill the @ec_hdr->ec + * field. + * + * This function returns zero in case of success and a negative error code in + * case of failure. If %-EIO is returned, the physical eraseblock most probably + * went bad. + */ +int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum, + struct ubi_ec_hdr *ec_hdr) +{ + int err; + uint32_t crc; + + dbg_io("write EC header to PEB %d", pnum); + ubi_assert(pnum >= 0 && pnum < ubi->peb_count); + + ec_hdr->magic = cpu_to_be32(UBI_EC_HDR_MAGIC); + ec_hdr->version = UBI_VERSION; + ec_hdr->vid_hdr_offset = cpu_to_be32(ubi->vid_hdr_offset); + ec_hdr->data_offset = cpu_to_be32(ubi->leb_start); + crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC); + ec_hdr->hdr_crc = cpu_to_be32(crc); + + err = paranoid_check_ec_hdr(ubi, pnum, ec_hdr); + if (err) + return -EINVAL; + + err = ubi_io_write(ubi, ec_hdr, pnum, 0, ubi->ec_hdr_alsize); + return err; +} + +/** + * validate_vid_hdr - validate a volume identifier header. + * @ubi: UBI device description object + * @vid_hdr: the volume identifier header to check + * + * This function checks that data stored in the volume identifier header + * @vid_hdr. Returns zero if the VID header is OK and %1 if not. + */ +static int validate_vid_hdr(const struct ubi_device *ubi, + const struct ubi_vid_hdr *vid_hdr) +{ + int vol_type = vid_hdr->vol_type; + int copy_flag = vid_hdr->copy_flag; + int vol_id = be32_to_cpu(vid_hdr->vol_id); + int lnum = be32_to_cpu(vid_hdr->lnum); + int compat = vid_hdr->compat; + int data_size = be32_to_cpu(vid_hdr->data_size); + int used_ebs = be32_to_cpu(vid_hdr->used_ebs); + int data_pad = be32_to_cpu(vid_hdr->data_pad); + int data_crc = be32_to_cpu(vid_hdr->data_crc); + int usable_leb_size = ubi->leb_size - data_pad; + + if (copy_flag != 0 && copy_flag != 1) { + dbg_err("bad copy_flag"); + goto bad; + } + + if (vol_id < 0 || lnum < 0 || data_size < 0 || used_ebs < 0 || + data_pad < 0) { + dbg_err("negative values"); + goto bad; + } + + if (vol_id >= UBI_MAX_VOLUMES && vol_id < UBI_INTERNAL_VOL_START) { + dbg_err("bad vol_id"); + goto bad; + } + + if (vol_id < UBI_INTERNAL_VOL_START && compat != 0) { + dbg_err("bad compat"); + goto bad; + } + + if (vol_id >= UBI_INTERNAL_VOL_START && compat != UBI_COMPAT_DELETE && + compat != UBI_COMPAT_RO && compat != UBI_COMPAT_PRESERVE && + compat != UBI_COMPAT_REJECT) { + dbg_err("bad compat"); + goto bad; + } + + if (vol_type != UBI_VID_DYNAMIC && vol_type != UBI_VID_STATIC) { + dbg_err("bad vol_type"); + goto bad; + } + + if (data_pad >= ubi->leb_size / 2) { + dbg_err("bad data_pad"); + goto bad; + } + + if (vol_type == UBI_VID_STATIC) { + /* + * Although from high-level point of view static volumes may + * contain zero bytes of data, but no VID headers can contain + * zero at these fields, because they empty volumes do not have + * mapped logical eraseblocks. + */ + if (used_ebs == 0) { + dbg_err("zero used_ebs"); + goto bad; + } + if (data_size == 0) { + dbg_err("zero data_size"); + goto bad; + } + if (lnum < used_ebs - 1) { + if (data_size != usable_leb_size) { + dbg_err("bad data_size"); + goto bad; + } + } else if (lnum == used_ebs - 1) { + if (data_size == 0) { + dbg_err("bad data_size at last LEB"); + goto bad; + } + } else { + dbg_err("too high lnum"); + goto bad; + } + } else { + if (copy_flag == 0) { + if (data_crc != 0) { + dbg_err("non-zero data CRC"); + goto bad; + } + if (data_size != 0) { + dbg_err("non-zero data_size"); + goto bad; + } + } else { + if (data_size == 0) { + dbg_err("zero data_size of copy"); + goto bad; + } + } + if (used_ebs != 0) { + dbg_err("bad used_ebs"); + goto bad; + } + } + + return 0; + +bad: + ubi_err("bad VID header"); + ubi_dbg_dump_vid_hdr(vid_hdr); + ubi_dbg_dump_stack(); + return 1; +} + +/** + * ubi_io_read_vid_hdr - read and check a volume identifier header. + * @ubi: UBI device description object + * @pnum: physical eraseblock number to read from + * @vid_hdr: &struct ubi_vid_hdr object where to store the read volume + * identifier header + * @verbose: be verbose if the header is corrupted or wasn't found + * + * This function reads the volume identifier header from physical eraseblock + * @pnum and stores it in @vid_hdr. It also checks CRC checksum of the read + * volume identifier header. The following codes may be returned: + * + * o %0 if the CRC checksum is correct and the header was successfully read; + * o %UBI_IO_BITFLIPS if the CRC is correct, but bit-flips were detected + * and corrected by the flash driver; this is harmless but may indicate that + * this eraseblock may become bad soon; + * o %UBI_IO_BAD_VID_HRD if the volume identifier header is corrupted (a CRC + * error detected); + * o %UBI_IO_PEB_FREE if the physical eraseblock is free (i.e., there is no VID + * header there); + * o a negative error code in case of failure. + */ +int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum, + struct ubi_vid_hdr *vid_hdr, int verbose) +{ + int err, read_err = 0; + uint32_t crc, magic, hdr_crc; + void *p; + + dbg_io("read VID header from PEB %d", pnum); + ubi_assert(pnum >= 0 && pnum < ubi->peb_count); + if (UBI_IO_DEBUG) + verbose = 1; + + p = (char *)vid_hdr - ubi->vid_hdr_shift; + err = ubi_io_read(ubi, p, pnum, ubi->vid_hdr_aloffset, + ubi->vid_hdr_alsize); + if (err) { + if (err != UBI_IO_BITFLIPS && err != -EBADMSG) + return err; + + /* + * We read all the data, but either a correctable bit-flip + * occurred, or MTD reported about some data integrity error, + * like an ECC error in case of NAND. The former is harmless, + * the later may mean the read data is corrupted. But we have a + * CRC check-sum and we will identify this. If the VID header is + * still OK, we just report this as there was a bit-flip. + */ + read_err = err; + } + + magic = be32_to_cpu(vid_hdr->magic); + if (magic != UBI_VID_HDR_MAGIC) { + /* + * If we have read all 0xFF bytes, the VID header probably does + * not exist and the physical eraseblock is assumed to be free. + * + * But if there was a read error, we do not test the data for + * 0xFFs. Even if it does contain all 0xFFs, this error + * indicates that something is still wrong with this physical + * eraseblock and it cannot be regarded as free. + */ + if (read_err != -EBADMSG && + check_pattern(vid_hdr, 0xFF, UBI_VID_HDR_SIZE)) { + /* The physical eraseblock is supposedly free */ + + /* + * The below is just a paranoid check, it has to be + * compiled out if paranoid checks are disabled. + */ + err = paranoid_check_all_ff(ubi, pnum, ubi->leb_start, + ubi->leb_size); + if (err) + return err > 0 ? UBI_IO_BAD_VID_HDR : err; + + if (verbose) + ubi_warn("no VID header found at PEB %d, " + "only 0xFF bytes", pnum); + return UBI_IO_PEB_FREE; + } + + /* + * This is not a valid VID header, and these are not 0xFF + * bytes. Report that the header is corrupted. + */ + if (verbose) { + ubi_warn("bad magic number at PEB %d: %08x instead of " + "%08x", pnum, magic, UBI_VID_HDR_MAGIC); + ubi_dbg_dump_vid_hdr(vid_hdr); + } + return UBI_IO_BAD_VID_HDR; + } + + crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_VID_HDR_SIZE_CRC); + hdr_crc = be32_to_cpu(vid_hdr->hdr_crc); + + if (hdr_crc != crc) { + if (verbose) { + ubi_warn("bad CRC at PEB %d, calculated %#08x, " + "read %#08x", pnum, crc, hdr_crc); + ubi_dbg_dump_vid_hdr(vid_hdr); + } + return UBI_IO_BAD_VID_HDR; + } + + /* Validate the VID header that we have just read */ + err = validate_vid_hdr(ubi, vid_hdr); + if (err) { + ubi_err("validation failed for PEB %d", pnum); + return -EINVAL; + } + + return read_err ? UBI_IO_BITFLIPS : 0; +} + +/** + * ubi_io_write_vid_hdr - write a volume identifier header. + * @ubi: UBI device description object + * @pnum: the physical eraseblock number to write to + * @vid_hdr: the volume identifier header to write + * + * This function writes the volume identifier header described by @vid_hdr to + * physical eraseblock @pnum. This function automatically fills the + * @vid_hdr->magic and the @vid_hdr->version fields, as well as calculates + * header CRC checksum and stores it at vid_hdr->hdr_crc. + * + * This function returns zero in case of success and a negative error code in + * case of failure. If %-EIO is returned, the physical eraseblock probably went + * bad. + */ +int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum, + struct ubi_vid_hdr *vid_hdr) +{ + int err; + uint32_t crc; + void *p; + + dbg_io("write VID header to PEB %d", pnum); + ubi_assert(pnum >= 0 && pnum < ubi->peb_count); + + err = paranoid_check_peb_ec_hdr(ubi, pnum); + if (err) + return err > 0 ? -EINVAL: err; + + vid_hdr->magic = cpu_to_be32(UBI_VID_HDR_MAGIC); + vid_hdr->version = UBI_VERSION; + crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_VID_HDR_SIZE_CRC); + vid_hdr->hdr_crc = cpu_to_be32(crc); + + err = paranoid_check_vid_hdr(ubi, pnum, vid_hdr); + if (err) + return -EINVAL; + + p = (char *)vid_hdr - ubi->vid_hdr_shift; + err = ubi_io_write(ubi, p, pnum, ubi->vid_hdr_aloffset, + ubi->vid_hdr_alsize); + return err; +} + +#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID + +/** + * paranoid_check_not_bad - ensure that a physical eraseblock is not bad. + * @ubi: UBI device description object + * @pnum: physical eraseblock number to check + * + * This function returns zero if the physical eraseblock is good, a positive + * number if it is bad and a negative error code if an error occurred. + */ +static int paranoid_check_not_bad(const struct ubi_device *ubi, int pnum) +{ + int err; + + err = ubi_io_is_bad(ubi, pnum); + if (!err) + return err; + + ubi_err("paranoid check failed for PEB %d", pnum); + ubi_dbg_dump_stack(); + return err; +} + +/** + * paranoid_check_ec_hdr - check if an erase counter header is all right. + * @ubi: UBI device description object + * @pnum: physical eraseblock number the erase counter header belongs to + * @ec_hdr: the erase counter header to check + * + * This function returns zero if the erase counter header contains valid + * values, and %1 if not. + */ +static int paranoid_check_ec_hdr(const struct ubi_device *ubi, int pnum, + const struct ubi_ec_hdr *ec_hdr) +{ + int err; + uint32_t magic; + + magic = be32_to_cpu(ec_hdr->magic); + if (magic != UBI_EC_HDR_MAGIC) { + ubi_err("bad magic %#08x, must be %#08x", + magic, UBI_EC_HDR_MAGIC); + goto fail; + } + + err = validate_ec_hdr(ubi, ec_hdr); + if (err) { + ubi_err("paranoid check failed for PEB %d", pnum); + goto fail; + } + + return 0; + +fail: + ubi_dbg_dump_ec_hdr(ec_hdr); + ubi_dbg_dump_stack(); + return 1; +} + +/** + * paranoid_check_peb_ec_hdr - check that the erase counter header of a + * physical eraseblock is in-place and is all right. + * @ubi: UBI device description object + * @pnum: the physical eraseblock number to check + * + * This function returns zero if the erase counter header is all right, %1 if + * not, and a negative error code if an error occurred. + */ +static int paranoid_check_peb_ec_hdr(const struct ubi_device *ubi, int pnum) +{ + int err; + uint32_t crc, hdr_crc; + struct ubi_ec_hdr *ec_hdr; + + ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS); + if (!ec_hdr) + return -ENOMEM; + + err = ubi_io_read(ubi, ec_hdr, pnum, 0, UBI_EC_HDR_SIZE); + if (err && err != UBI_IO_BITFLIPS && err != -EBADMSG) + goto exit; + + crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC); + hdr_crc = be32_to_cpu(ec_hdr->hdr_crc); + if (hdr_crc != crc) { + ubi_err("bad CRC, calculated %#08x, read %#08x", crc, hdr_crc); + ubi_err("paranoid check failed for PEB %d", pnum); + ubi_dbg_dump_ec_hdr(ec_hdr); + ubi_dbg_dump_stack(); + err = 1; + goto exit; + } + + err = paranoid_check_ec_hdr(ubi, pnum, ec_hdr); + +exit: + kfree(ec_hdr); + return err; +} + +/** + * paranoid_check_vid_hdr - check that a volume identifier header is all right. + * @ubi: UBI device description object + * @pnum: physical eraseblock number the volume identifier header belongs to + * @vid_hdr: the volume identifier header to check + * + * This function returns zero if the volume identifier header is all right, and + * %1 if not. + */ +static int paranoid_check_vid_hdr(const struct ubi_device *ubi, int pnum, + const struct ubi_vid_hdr *vid_hdr) +{ + int err; + uint32_t magic; + + magic = be32_to_cpu(vid_hdr->magic); + if (magic != UBI_VID_HDR_MAGIC) { + ubi_err("bad VID header magic %#08x at PEB %d, must be %#08x", + magic, pnum, UBI_VID_HDR_MAGIC); + goto fail; + } + + err = validate_vid_hdr(ubi, vid_hdr); + if (err) { + ubi_err("paranoid check failed for PEB %d", pnum); + goto fail; + } + + return err; + +fail: + ubi_err("paranoid check failed for PEB %d", pnum); + ubi_dbg_dump_vid_hdr(vid_hdr); + ubi_dbg_dump_stack(); + return 1; + +} + +/** + * paranoid_check_peb_vid_hdr - check that the volume identifier header of a + * physical eraseblock is in-place and is all right. + * @ubi: UBI device description object + * @pnum: the physical eraseblock number to check + * + * This function returns zero if the volume identifier header is all right, + * %1 if not, and a negative error code if an error occurred. + */ +static int paranoid_check_peb_vid_hdr(const struct ubi_device *ubi, int pnum) +{ + int err; + uint32_t crc, hdr_crc; + struct ubi_vid_hdr *vid_hdr; + void *p; + + vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS); + if (!vid_hdr) + return -ENOMEM; + + p = (char *)vid_hdr - ubi->vid_hdr_shift; + err = ubi_io_read(ubi, p, pnum, ubi->vid_hdr_aloffset, + ubi->vid_hdr_alsize); + if (err && err != UBI_IO_BITFLIPS && err != -EBADMSG) + goto exit; + + crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_EC_HDR_SIZE_CRC); + hdr_crc = be32_to_cpu(vid_hdr->hdr_crc); + if (hdr_crc != crc) { + ubi_err("bad VID header CRC at PEB %d, calculated %#08x, " + "read %#08x", pnum, crc, hdr_crc); + ubi_err("paranoid check failed for PEB %d", pnum); + ubi_dbg_dump_vid_hdr(vid_hdr); + ubi_dbg_dump_stack(); + err = 1; + goto exit; + } + + err = paranoid_check_vid_hdr(ubi, pnum, vid_hdr); + +exit: + ubi_free_vid_hdr(ubi, vid_hdr); + return err; +} + +/** + * paranoid_check_all_ff - check that a region of flash is empty. + * @ubi: UBI device description object + * @pnum: the physical eraseblock number to check + * @offset: the starting offset within the physical eraseblock to check + * @len: the length of the region to check + * + * This function returns zero if only 0xFF bytes are present at offset + * @offset of the physical eraseblock @pnum, %1 if not, and a negative error + * code if an error occurred. + */ +static int paranoid_check_all_ff(struct ubi_device *ubi, int pnum, int offset, + int len) +{ + size_t read; + int err; + loff_t addr = (loff_t)pnum * ubi->peb_size + offset; + + mutex_lock(&ubi->dbg_buf_mutex); + err = ubi->mtd->read(ubi->mtd, addr, len, &read, ubi->dbg_peb_buf); + if (err && err != -EUCLEAN) { + ubi_err("error %d while reading %d bytes from PEB %d:%d, " + "read %zd bytes", err, len, pnum, offset, read); + goto error; + } + + err = check_pattern(ubi->dbg_peb_buf, 0xFF, len); + if (err == 0) { + ubi_err("flash region at PEB %d:%d, length %d does not " + "contain all 0xFF bytes", pnum, offset, len); + goto fail; + } + mutex_unlock(&ubi->dbg_buf_mutex); + + return 0; + +fail: + ubi_err("paranoid check failed for PEB %d", pnum); + dbg_msg("hex dump of the %d-%d region", offset, offset + len); + print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1, + ubi->dbg_peb_buf, len, 1); + err = 1; +error: + ubi_dbg_dump_stack(); + mutex_unlock(&ubi->dbg_buf_mutex); + return err; +} + +#endif /* CONFIG_MTD_UBI_DEBUG_PARANOID */ diff --git a/drivers/mtd/ubi/kapi.c b/drivers/mtd/ubi/kapi.c new file mode 100644 index 0000000..423d479 --- /dev/null +++ b/drivers/mtd/ubi/kapi.c @@ -0,0 +1,638 @@ +/* + * Copyright (c) International Business Machines Corp., 2006 + * + * 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 + * + * Author: Artem Bityutskiy (Битюцкий Артём) + */ + +/* This file mostly implements UBI kernel API functions */ + +#ifdef UBI_LINUX +#include <linux/module.h> +#include <linux/err.h> +#include <asm/div64.h> +#endif + +#include <ubi_uboot.h> +#include "ubi.h" + +/** + * ubi_get_device_info - get information about UBI device. + * @ubi_num: UBI device number + * @di: the information is stored here + * + * This function returns %0 in case of success, %-EINVAL if the UBI device + * number is invalid, and %-ENODEV if there is no such UBI device. + */ +int ubi_get_device_info(int ubi_num, struct ubi_device_info *di) +{ + struct ubi_device *ubi; + + if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES) + return -EINVAL; + + ubi = ubi_get_device(ubi_num); + if (!ubi) + return -ENODEV; + + di->ubi_num = ubi->ubi_num; + di->leb_size = ubi->leb_size; + di->min_io_size = ubi->min_io_size; + di->ro_mode = ubi->ro_mode; + di->cdev = ubi->cdev.dev; + + ubi_put_device(ubi); + return 0; +} +EXPORT_SYMBOL_GPL(ubi_get_device_info); + +/** + * ubi_get_volume_info - get information about UBI volume. + * @desc: volume descriptor + * @vi: the information is stored here + */ +void ubi_get_volume_info(struct ubi_volume_desc *desc, + struct ubi_volume_info *vi) +{ + const struct ubi_volume *vol = desc->vol; + const struct ubi_device *ubi = vol->ubi; + + vi->vol_id = vol->vol_id; + vi->ubi_num = ubi->ubi_num; + vi->size = vol->reserved_pebs; + vi->used_bytes = vol->used_bytes; + vi->vol_type = vol->vol_type; + vi->corrupted = vol->corrupted; + vi->upd_marker = vol->upd_marker; + vi->alignment = vol->alignment; + vi->usable_leb_size = vol->usable_leb_size; + vi->name_len = vol->name_len; + vi->name = vol->name; + vi->cdev = vol->cdev.dev; +} +EXPORT_SYMBOL_GPL(ubi_get_volume_info); + +/** + * ubi_open_volume - open UBI volume. + * @ubi_num: UBI device number + * @vol_id: volume ID + * @mode: open mode + * + * The @mode parameter specifies if the volume should be opened in read-only + * mode, read-write mode, or exclusive mode. The exclusive mode guarantees that + * nobody else will be able to open this volume. UBI allows to have many volume + * readers and one writer at a time. + * + * If a static volume is being opened for the first time since boot, it will be + * checked by this function, which means it will be fully read and the CRC + * checksum of each logical eraseblock will be checked. + * + * This function returns volume descriptor in case of success and a negative + * error code in case of failure. + */ +struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode) +{ + int err; + struct ubi_volume_desc *desc; + struct ubi_device *ubi; + struct ubi_volume *vol; + + dbg_msg("open device %d volume %d, mode %d", ubi_num, vol_id, mode); + + if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES) + return ERR_PTR(-EINVAL); + + if (mode != UBI_READONLY && mode != UBI_READWRITE && + mode != UBI_EXCLUSIVE) + return ERR_PTR(-EINVAL); + + /* + * First of all, we have to get the UBI device to prevent its removal. + */ + ubi = ubi_get_device(ubi_num); + if (!ubi) + return ERR_PTR(-ENODEV); + + if (vol_id < 0 || vol_id >= ubi->vtbl_slots) { + err = -EINVAL; + goto out_put_ubi; + } + + desc = kmalloc(sizeof(struct ubi_volume_desc), GFP_KERNEL); + if (!desc) { + err = -ENOMEM; + goto out_put_ubi; + } + + err = -ENODEV; + if (!try_module_get(THIS_MODULE)) + goto out_free; + + spin_lock(&ubi->volumes_lock); + vol = ubi->volumes[vol_id]; + if (!vol) + goto out_unlock; + + err = -EBUSY; + switch (mode) { + case UBI_READONLY: + if (vol->exclusive) + goto out_unlock; + vol->readers += 1; + break; + + case UBI_READWRITE: + if (vol->exclusive || vol->writers > 0) + goto out_unlock; + vol->writers += 1; + break; + + case UBI_EXCLUSIVE: + if (vol->exclusive || vol->writers || vol->readers) + goto out_unlock; + vol->exclusive = 1; + break; + } + get_device(&vol->dev); + vol->ref_count += 1; + spin_unlock(&ubi->volumes_lock); + + desc->vol = vol; + desc->mode = mode; + + mutex_lock(&ubi->ckvol_mutex); + if (!vol->checked) { + /* This is the first open - check the volume */ + err = ubi_check_volume(ubi, vol_id); + if (err < 0) { + mutex_unlock(&ubi->ckvol_mutex); + ubi_close_volume(desc); + return ERR_PTR(err); + } + if (err == 1) { + ubi_warn("volume %d on UBI device %d is corrupted", + vol_id, ubi->ubi_num); + vol->corrupted = 1; + } + vol->checked = 1; + } + mutex_unlock(&ubi->ckvol_mutex); + + return desc; + +out_unlock: + spin_unlock(&ubi->volumes_lock); + module_put(THIS_MODULE); +out_free: + kfree(desc); +out_put_ubi: + ubi_put_device(ubi); + return ERR_PTR(err); +} +EXPORT_SYMBOL_GPL(ubi_open_volume); + +/** + * ubi_open_volume_nm - open UBI volume by name. + * @ubi_num: UBI device number + * @name: volume name + * @mode: open mode + * + * This function is similar to 'ubi_open_volume()', but opens a volume by name. + */ +struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name, + int mode) +{ + int i, vol_id = -1, len; + struct ubi_device *ubi; + struct ubi_volume_desc *ret; + + dbg_msg("open volume %s, mode %d", name, mode); + + if (!name) + return ERR_PTR(-EINVAL); + + len = strnlen(name, UBI_VOL_NAME_MAX + 1); + if (len > UBI_VOL_NAME_MAX) + return ERR_PTR(-EINVAL); + + if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES) + return ERR_PTR(-EINVAL); + + ubi = ubi_get_device(ubi_num); + if (!ubi) + return ERR_PTR(-ENODEV); + + spin_lock(&ubi->volumes_lock); + /* Walk all volumes of this UBI device */ + for (i = 0; i < ubi->vtbl_slots; i++) { + struct ubi_volume *vol = ubi->volumes[i]; + + if (vol && len == vol->name_len && !strcmp(name, vol->name)) { + vol_id = i; + break; + } + } + spin_unlock(&ubi->volumes_lock); + + if (vol_id >= 0) + ret = ubi_open_volume(ubi_num, vol_id, mode); + else + ret = ERR_PTR(-ENODEV); + + /* + * We should put the UBI device even in case of success, because + * 'ubi_open_volume()' took a reference as well. + */ + ubi_put_device(ubi); + return ret; +} +EXPORT_SYMBOL_GPL(ubi_open_volume_nm); + +/** + * ubi_close_volume - close UBI volume. + * @desc: volume descriptor + */ +void ubi_close_volume(struct ubi_volume_desc *desc) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + + dbg_msg("close volume %d, mode %d", vol->vol_id, desc->mode); + + spin_lock(&ubi->volumes_lock); + switch (desc->mode) { + case UBI_READONLY: + vol->readers -= 1; + break; + case UBI_READWRITE: + vol->writers -= 1; + break; + case UBI_EXCLUSIVE: + vol->exclusive = 0; + } + vol->ref_count -= 1; + spin_unlock(&ubi->volumes_lock); + + kfree(desc); + put_device(&vol->dev); + ubi_put_device(ubi); + module_put(THIS_MODULE); +} +EXPORT_SYMBOL_GPL(ubi_close_volume); + +/** + * ubi_leb_read - read data. + * @desc: volume descriptor + * @lnum: logical eraseblock number to read from + * @buf: buffer where to store the read data + * @offset: offset within the logical eraseblock to read from + * @len: how many bytes to read + * @check: whether UBI has to check the read data's CRC or not. + * + * This function reads data from offset @offset of logical eraseblock @lnum and + * stores the data at @buf. When reading from static volumes, @check specifies + * whether the data has to be checked or not. If yes, the whole logical + * eraseblock will be read and its CRC checksum will be checked (i.e., the CRC + * checksum is per-eraseblock). So checking may substantially slow down the + * read speed. The @check argument is ignored for dynamic volumes. + * + * In case of success, this function returns zero. In case of failure, this + * function returns a negative error code. + * + * %-EBADMSG error code is returned: + * o for both static and dynamic volumes if MTD driver has detected a data + * integrity problem (unrecoverable ECC checksum mismatch in case of NAND); + * o for static volumes in case of data CRC mismatch. + * + * If the volume is damaged because of an interrupted update this function just + * returns immediately with %-EBADF error code. + */ +int ubi_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset, + int len, int check) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + int err, vol_id = vol->vol_id; + + dbg_msg("read %d bytes from LEB %d:%d:%d", len, vol_id, lnum, offset); + + if (vol_id < 0 || vol_id >= ubi->vtbl_slots || lnum < 0 || + lnum >= vol->used_ebs || offset < 0 || len < 0 || + offset + len > vol->usable_leb_size) + return -EINVAL; + + if (vol->vol_type == UBI_STATIC_VOLUME) { + if (vol->used_ebs == 0) + /* Empty static UBI volume */ + return 0; + if (lnum == vol->used_ebs - 1 && + offset + len > vol->last_eb_bytes) + return -EINVAL; + } + + if (vol->upd_marker) + return -EBADF; + if (len == 0) + return 0; + + err = ubi_eba_read_leb(ubi, vol, lnum, buf, offset, len, check); + if (err && err == -EBADMSG && vol->vol_type == UBI_STATIC_VOLUME) { + ubi_warn("mark volume %d as corrupted", vol_id); + vol->corrupted = 1; + } + + return err; +} +EXPORT_SYMBOL_GPL(ubi_leb_read); + +/** + * ubi_leb_write - write data. + * @desc: volume descriptor + * @lnum: logical eraseblock number to write to + * @buf: data to write + * @offset: offset within the logical eraseblock where to write + * @len: how many bytes to write + * @dtype: expected data type + * + * This function writes @len bytes of data from @buf to offset @offset of + * logical eraseblock @lnum. The @dtype argument describes expected lifetime of + * the data. + * + * This function takes care of physical eraseblock write failures. If write to + * the physical eraseblock write operation fails, the logical eraseblock is + * re-mapped to another physical eraseblock, the data is recovered, and the + * write finishes. UBI has a pool of reserved physical eraseblocks for this. + * + * If all the data were successfully written, zero is returned. If an error + * occurred and UBI has not been able to recover from it, this function returns + * a negative error code. Note, in case of an error, it is possible that + * something was still written to the flash media, but that may be some + * garbage. + * + * If the volume is damaged because of an interrupted update this function just + * returns immediately with %-EBADF code. + */ +int ubi_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf, + int offset, int len, int dtype) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + int vol_id = vol->vol_id; + + dbg_msg("write %d bytes to LEB %d:%d:%d", len, vol_id, lnum, offset); + + if (vol_id < 0 || vol_id >= ubi->vtbl_slots) + return -EINVAL; + + if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) + return -EROFS; + + if (lnum < 0 || lnum >= vol->reserved_pebs || offset < 0 || len < 0 || + offset + len > vol->usable_leb_size || + offset & (ubi->min_io_size - 1) || len & (ubi->min_io_size - 1)) + return -EINVAL; + + if (dtype != UBI_LONGTERM && dtype != UBI_SHORTTERM && + dtype != UBI_UNKNOWN) + return -EINVAL; + + if (vol->upd_marker) + return -EBADF; + + if (len == 0) + return 0; + + return ubi_eba_write_leb(ubi, vol, lnum, buf, offset, len, dtype); +} +EXPORT_SYMBOL_GPL(ubi_leb_write); + +/* + * ubi_leb_change - change logical eraseblock atomically. + * @desc: volume descriptor + * @lnum: logical eraseblock number to change + * @buf: data to write + * @len: how many bytes to write + * @dtype: expected data type + * + * This function changes the contents of a logical eraseblock atomically. @buf + * has to contain new logical eraseblock data, and @len - the length of the + * data, which has to be aligned. The length may be shorter then the logical + * eraseblock size, ant the logical eraseblock may be appended to more times + * later on. This function guarantees that in case of an unclean reboot the old + * contents is preserved. Returns zero in case of success and a negative error + * code in case of failure. + */ +int ubi_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf, + int len, int dtype) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + int vol_id = vol->vol_id; + + dbg_msg("atomically write %d bytes to LEB %d:%d", len, vol_id, lnum); + + if (vol_id < 0 || vol_id >= ubi->vtbl_slots) + return -EINVAL; + + if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) + return -EROFS; + + if (lnum < 0 || lnum >= vol->reserved_pebs || len < 0 || + len > vol->usable_leb_size || len & (ubi->min_io_size - 1)) + return -EINVAL; + + if (dtype != UBI_LONGTERM && dtype != UBI_SHORTTERM && + dtype != UBI_UNKNOWN) + return -EINVAL; + + if (vol->upd_marker) + return -EBADF; + + if (len == 0) + return 0; + + return ubi_eba_atomic_leb_change(ubi, vol, lnum, buf, len, dtype); +} +EXPORT_SYMBOL_GPL(ubi_leb_change); + +/** + * ubi_leb_erase - erase logical eraseblock. + * @desc: volume descriptor + * @lnum: logical eraseblock number + * + * This function un-maps logical eraseblock @lnum and synchronously erases the + * correspondent physical eraseblock. Returns zero in case of success and a + * negative error code in case of failure. + * + * If the volume is damaged because of an interrupted update this function just + * returns immediately with %-EBADF code. + */ +int ubi_leb_erase(struct ubi_volume_desc *desc, int lnum) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + int err; + + dbg_msg("erase LEB %d:%d", vol->vol_id, lnum); + + if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) + return -EROFS; + + if (lnum < 0 || lnum >= vol->reserved_pebs) + return -EINVAL; + + if (vol->upd_marker) + return -EBADF; + + err = ubi_eba_unmap_leb(ubi, vol, lnum); + if (err) + return err; + + return ubi_wl_flush(ubi); +} +EXPORT_SYMBOL_GPL(ubi_leb_erase); + +/** + * ubi_leb_unmap - un-map logical eraseblock. + * @desc: volume descriptor + * @lnum: logical eraseblock number + * + * This function un-maps logical eraseblock @lnum and schedules the + * corresponding physical eraseblock for erasure, so that it will eventually be + * physically erased in background. This operation is much faster then the + * erase operation. + * + * Unlike erase, the un-map operation does not guarantee that the logical + * eraseblock will contain all 0xFF bytes when UBI is initialized again. For + * example, if several logical eraseblocks are un-mapped, and an unclean reboot + * happens after this, the logical eraseblocks will not necessarily be + * un-mapped again when this MTD device is attached. They may actually be + * mapped to the same physical eraseblocks again. So, this function has to be + * used with care. + * + * In other words, when un-mapping a logical eraseblock, UBI does not store + * any information about this on the flash media, it just marks the logical + * eraseblock as "un-mapped" in RAM. If UBI is detached before the physical + * eraseblock is physically erased, it will be mapped again to the same logical + * eraseblock when the MTD device is attached again. + * + * The main and obvious use-case of this function is when the contents of a + * logical eraseblock has to be re-written. Then it is much more efficient to + * first un-map it, then write new data, rather then first erase it, then write + * new data. Note, once new data has been written to the logical eraseblock, + * UBI guarantees that the old contents has gone forever. In other words, if an + * unclean reboot happens after the logical eraseblock has been un-mapped and + * then written to, it will contain the last written data. + * + * This function returns zero in case of success and a negative error code in + * case of failure. If the volume is damaged because of an interrupted update + * this function just returns immediately with %-EBADF code. + */ +int ubi_leb_unmap(struct ubi_volume_desc *desc, int lnum) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + + dbg_msg("unmap LEB %d:%d", vol->vol_id, lnum); + + if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) + return -EROFS; + + if (lnum < 0 || lnum >= vol->reserved_pebs) + return -EINVAL; + + if (vol->upd_marker) + return -EBADF; + + return ubi_eba_unmap_leb(ubi, vol, lnum); +} +EXPORT_SYMBOL_GPL(ubi_leb_unmap); + +/** + * ubi_leb_map - map logical erasblock to a physical eraseblock. + * @desc: volume descriptor + * @lnum: logical eraseblock number + * @dtype: expected data type + * + * This function maps an un-mapped logical eraseblock @lnum to a physical + * eraseblock. This means, that after a successfull invocation of this + * function the logical eraseblock @lnum will be empty (contain only %0xFF + * bytes) and be mapped to a physical eraseblock, even if an unclean reboot + * happens. + * + * This function returns zero in case of success, %-EBADF if the volume is + * damaged because of an interrupted update, %-EBADMSG if the logical + * eraseblock is already mapped, and other negative error codes in case of + * other failures. + */ +int ubi_leb_map(struct ubi_volume_desc *desc, int lnum, int dtype) +{ + struct ubi_volume *vol = desc->vol; + struct ubi_device *ubi = vol->ubi; + + dbg_msg("unmap LEB %d:%d", vol->vol_id, lnum); + + if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) + return -EROFS; + + if (lnum < 0 || lnum >= vol->reserved_pebs) + return -EINVAL; + + if (dtype != UBI_LONGTERM && dtype != UBI_SHORTTERM && + dtype != UBI_UNKNOWN) + return -EINVAL; + + if (vol->upd_marker) + return -EBADF; + + if (vol->eba_tbl[lnum] >= 0) + return -EBADMSG; + + return ubi_eba_write_leb(ubi, vol, lnum, NULL, 0, 0, dtype); +} +EXPORT_SYMBOL_GPL(ubi_leb_map); + +/** + * ubi_is_mapped - check if logical eraseblock is mapped. + * @desc: volume descriptor + * @lnum: logical eraseblock number + * + * This function checks if logical eraseblock @lnum is mapped to a physical + * eraseblock. If a logical eraseblock is un-mapped, this does not necessarily + * mean it will still be un-mapped after the UBI device is re-attached. The + * logical eraseblock may become mapped to the physical eraseblock it was last + * mapped to. + * + * This function returns %1 if the LEB is mapped, %0 if not, and a negative + * error code in case of failure. If the volume is damaged because of an + * interrupted update this function just returns immediately with %-EBADF error + * code. + */ +int ubi_is_mapped(struct ubi_volume_desc *desc, int lnum) +{ + struct ubi_volume *vol = desc->vol; + + dbg_msg("test LEB %d:%d", vol->vol_id, lnum); + + if (lnum < 0 || lnum >= vol->reserved_pebs) + return -EINVAL; + + if (vol->upd_marker) + return -EBADF; + + return vol->eba_tbl[lnum] >= 0; +} +EXPORT_SYMBOL_GPL(ubi_is_mapped); diff --git a/drivers/mtd/ubi/misc.c b/drivers/mtd/ubi/misc.c new file mode 100644 index 0000000..a6410bf --- /dev/null +++ b/drivers/mtd/ubi/misc.c @@ -0,0 +1,106 @@ +/* + * Copyright (c) International Business Machines Corp., 2006 + * + * 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 + * + * Author: Artem Bityutskiy (Битюцкий Артём) + */ + +/* Here we keep miscellaneous functions which are used all over the UBI code */ + +#include <ubi_uboot.h> +#include "ubi.h" + +/** + * calc_data_len - calculate how much real data is stored in a buffer. + * @ubi: UBI device description object + * @buf: a buffer with the contents of the physical eraseblock + * @length: the buffer length + * + * This function calculates how much "real data" is stored in @buf and returnes + * the length. Continuous 0xFF bytes at the end of the buffer are not + * considered as "real data". + */ +int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf, + int length) +{ + int i; + + ubi_assert(!(length & (ubi->min_io_size - 1))); + + for (i = length - 1; i >= 0; i--) + if (((const uint8_t *)buf)[i] != 0xFF) + break; + + /* The resulting length must be aligned to the minimum flash I/O size */ + length = ALIGN(i + 1, ubi->min_io_size); + return length; +} + +/** + * ubi_check_volume - check the contents of a static volume. + * @ubi: UBI device description object + * @vol_id: ID of the volume to check + * + * This function checks if static volume @vol_id is corrupted by fully reading + * it and checking data CRC. This function returns %0 if the volume is not + * corrupted, %1 if it is corrupted and a negative error code in case of + * failure. Dynamic volumes are not checked and zero is returned immediately. + */ +int ubi_check_volume(struct ubi_device *ubi, int vol_id) +{ + void *buf; + int err = 0, i; + struct ubi_volume *vol = ubi->volumes[vol_id]; + + if (vol->vol_type != UBI_STATIC_VOLUME) + return 0; + + buf = vmalloc(vol->usable_leb_size); + if (!buf) + return -ENOMEM; + + for (i = 0; i < vol->used_ebs; i++) { + int size; + + if (i == vol->used_ebs - 1) + size = vol->last_eb_bytes; + else + size = vol->usable_leb_size; + + err = ubi_eba_read_leb(ubi, vol, i, buf, 0, size, 1); + if (err) { + if (err == -EBADMSG) + err = 1; + break; + } + } + + vfree(buf); + return err; +} + +/** + * ubi_calculate_rsvd_pool - calculate how many PEBs must be reserved for bad + * eraseblock handling. + * @ubi: UBI device description object + */ +void ubi_calculate_reserved(struct ubi_device *ubi) +{ + ubi->beb_rsvd_level = ubi->good_peb_count/100; + ubi->beb_rsvd_level *= CONFIG_MTD_UBI_BEB_RESERVE; + if (ubi->beb_rsvd_level < MIN_RESEVED_PEBS) + ubi->beb_rsvd_level = MIN_RESEVED_PEBS; +} |