/**
* 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 = ubi_dbg_check_all_ff(ubi, pnum, 0, ubi->peb_size);
if (err)
return err;
if (ubi_dbg_is_erase_failure() && !err) {
dbg_err("cannot erase PEB %d (emulated)", pnum);
return -EIO;
}
return 0;
}
/**
* paranoid_check_peb_ec_hdr - check erase counter header.
* @ubi: UBI device description object
* @pnum: the physical eraseblock number to check
*
* This function returns zero if the erase counter header is all right and and
* a negative error code if not or 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 = -EINVAL;
goto exit;
}
err = paranoid_check_ec_hdr(ubi, pnum, ec_hdr);
exit:
kfree(ec_hdr);
return err;
}
/**
* paranoid_check_peb_vid_hdr - check volume identifier header.
* @ubi: UBI device description object
* @pnum: the physical eraseblock number to check
*
* This function returns zero if the volume identifier header is all right,
* and a negative error code if not or 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 = -EINVAL;
goto exit;
}
err = paranoid_check_vid_hdr(ubi, pnum, vid_hdr);
exit:
ubi_free_vid_hdr(ubi, vid_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
* %-EINVAL 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 -EINVAL;
}
/* Write one page with oob one time */
int ubi_io_write_oob(const struct ubi_device *ubi, void *databuf, void *oobbuf,
int pnum, int offset)
{
int err;
loff_t addr;
struct mtd_oob_ops ops;
dbg_io("read from PEB %d:%d", pnum, offset);
ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
ubi_assert(offset >= 0 && offset + ubi->mtd->writesize <= ubi->peb_size);
addr = (loff_t)pnum * ubi->peb_size + offset;
ops.mode = MTD_OPS_AUTO_OOB;
ops.ooblen = ubi->mtd->oobavail;
ops.oobbuf = oobbuf;
ops.ooboffs = 0;
ops.len = ubi->mtd->writesize;
ops.datbuf = databuf;
ops.retlen = ops.oobretlen = 0;
err = mtd_write_oob(ubi->mtd, addr, &ops);
if (err) {
ubi_err("error %d while writing to addr %lld, written ",
err, addr);
ubi_dbg_dump_stack();
} else
ubi_assert(ops.retlen == ops.len);
return err;
}
/**
* ubi_dbg_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, and a negative error code if not
* or if an error occurred.
*/
int ubi_dbg_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);
ubi_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 = -EINVAL;
error:
ubi_dbg_dump_stack();
mutex_unlock(&ubi->dbg_buf_mutex);
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 %-EINVAL 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 -EINVAL;
}
/**
* 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();
} else {
ubi_assert(len == read);
if (ubi_dbg_is_bitflip()) {
dbg_msg("bit-flip (emulated)");
err = UBI_IO_BITFLIPS;
}
}
return err;
}
/**
* ubi_dbg_check_write - make sure write succeeded.
* @ubi: UBI device description object
* @buf: buffer with data which were written
* @pnum: physical eraseblock number the data were written to
* @offset: offset within the physical eraseblock the data were written to
* @len: how many bytes were written
*
* This functions reads data which were recently written and compares it with
* the original data buffer - the data have to match. Returns zero if the data
* match and a negative error code if not or in case of failure.
*/
int ubi_dbg_check_write(struct ubi_device *ubi, const void *buf, int pnum,
int offset, int len)
{
int err, i;
size_t read;
void *buf1;
loff_t addr = (loff_t)pnum * ubi->peb_size + offset;
if (!ubi->dbg->chk_io)
return 0;
buf1 = kmalloc(len, GFP_KERNEL);
if (!buf1) {
ubi_err("cannot allocate memory to check writes");
return 0;
}
err = mtd_read(ubi->mtd, addr, len, &read, buf1);
if (err && !mtd_is_bitflip(err))
goto out_free;
for (i = 0; i < len; i++) {
uint8_t c = ((uint8_t *)buf)[i];
uint8_t c1 = ((uint8_t *)buf1)[i];
int dump_len;
if (c == c1)
continue;
ubi_err("paranoid check failed for PEB %d:%d, len %d",
pnum, offset, len);
ubi_msg("data differ at position %d", i);
dump_len = max_t(int, 128, len - i);
ubi_msg("hex dump of the original buffer from %d to %d",
i, i + dump_len);
print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
buf + i, dump_len, 1);
ubi_msg("hex dump of the read buffer from %d to %d",
i, i + dump_len);
print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
buf1 + i, dump_len, 1);
ubi_dbg_dump_stack();
err = -EINVAL;
goto out_free;
}
kfree(buf1);
return 0;
out_free:
kfree(buf1);
return err;
}
/**
* 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, %-EINVAL 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 > 0 ? -EINVAL : 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;
}
//printf("ELVIS---ec_hdr->vid_hdr_offset:%d, ubi->vid_hdr_offset:%d",
// vid_hdr_offset, ubi->vid_hdr_offset);
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_dbg_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, and a negative error code if not
* or if an error occurred.
*/
int ubi_dbg_check_all_ff(struct ubi_device *ubi, int pnum, int offset, int len)
{
size_t read;
int err;
void *buf;
loff_t addr = (loff_t)pnum * ubi->peb_size + offset;
if (!ubi->dbg->chk_io)
return 0;
buf = kmalloc(len, GFP_KERNEL);
if (!buf) {
ubi_err("cannot allocate memory to check for 0xFFs");
return 0;
}
err = mtd_read(ubi->mtd, addr, len, &read, buf);
if (err && !mtd_is_bitflip(err)) {
ubi_err("error %d while reading %d bytes from PEB %d:%d, "
"read %zd bytes", err, len, pnum, offset, read);
goto error;
}
err = ubi_check_pattern(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;
}
kfree(buf);
return 0;
fail:
ubi_err("paranoid check failed for PEB %d", pnum);
ubi_msg("hex dump of the %d-%d region", offset, offset + len);
print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1, buf, len, 1);
err = -EINVAL;
error:
ubi_dbg_dump_stack();
kfree(buf);
return err;
}
/**
* ubi_dbg_check_write - make sure write succeeded.
* @ubi: UBI device description object
* @buf: buffer with data which were written
* @pnum: physical eraseblock number the data were written to
* @offset: offset within the physical eraseblock the data were written to
* @len: how many bytes were written
*
* This functions reads data which were recently written and compares it with
* the original data buffer - the data have to match. Returns zero if the data
* match and a negative error code if not or in case of failure.
*/
int ubi_dbg_check_write(struct ubi_device *ubi, const void *buf, int pnum,
int offset, int len)
{
int err, i;
mutex_lock(&ubi->dbg_buf_mutex);
err = ubi_io_read(ubi, ubi->dbg_peb_buf, pnum, offset, len);
if (err)
goto out_unlock;
for (i = 0; i < len; i++) {
uint8_t c = ((uint8_t *)buf)[i];
uint8_t c1 = ((uint8_t *)ubi->dbg_peb_buf)[i];
int dump_len;
if (c == c1)
continue;
ubi_err("paranoid check failed for PEB %d:%d, len %d",
pnum, offset, len);
ubi_msg("data differ at position %d", i);
dump_len = max_t(int, 128, len - i);
ubi_msg("hex dump of the original buffer from %d to %d",
i, i + dump_len);
print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
buf + i, dump_len, 1);
ubi_msg("hex dump of the read buffer from %d to %d",
i, i + dump_len);
print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
ubi->dbg_peb_buf + i, dump_len, 1);
ubi_dbg_dump_stack();
err = -EINVAL;
goto out_unlock;
}
mutex_unlock(&ubi->dbg_buf_mutex);
return 0;
out_unlock:
mutex_unlock(&ubi->dbg_buf_mutex);
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;
/* The area we are writing to has to contain all 0xFF bytes */
err = ubi_dbg_check_all_ff(ubi, pnum, offset, len);
if (err)
return 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;
err = paranoid_check_peb_vid_hdr(ubi, pnum);
if (err)
return 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();
ubi_dbg_dump_flash(ubi, pnum, offset, len);
} else
ubi_assert(written == len);
if (!err) {
err = ubi_dbg_check_write(ubi, buf, pnum, offset, len);
if (err)
return err;
/*
* Since we always write sequentially, the rest of the PEB has
* to contain only 0xFF bytes.
*/
offset += len;
len = ubi->peb_size - offset;
if (len)
err = ubi_dbg_check_all_ff(ubi, pnum, offset, len);
}
return err;
}
/**
* 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;
addr = (loff_t)pnum * ubi->peb_size + offset;
retry:
err = ubi->mtd->read(ubi->mtd, addr, len, &read, buf);
if (err == -EUCLEAN) err = 0; //added by Elvis, for ignore EUCLEAN
if (err) {
if (err == -EUCLEAN) {
/*
* -EUCLEAN is reported if there was a bit-flip which
* was corrected, so this is harmless.
*
* We do not report about it here unless debugging is
* enabled. A corresponding message will be printed
* later, when it is has been scrubbed.
*/
dbg_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);
err = -EIO;
}
} else {
ubi_assert(len == read);
if (ubi_dbg_is_bitflip()) {
dbg_gen("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;
#ifdef CONFIG_MTD_MSM_NAND
void *buf_new;
#endif
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 = ubi_dbg_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;
#ifdef CONFIG_MTD_MSM_NAND
if(!(buf_new = kmalloc(len, GFP_KERNEL | __GFP_NOFAIL)))
return -ENOMEM;
memcpy(buf_new, buf, len);
err = ubi->mtd->write(ubi->mtd, addr, len, &written, buf_new);
#else
err = ubi->mtd->write(ubi->mtd, addr, len, &written, buf);
#endif
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();
ubi_dbg_dump_flash(ubi, pnum, offset, len);
} else
ubi_assert(written == len);
#ifdef CONFIG_MTD_MSM_NAND
kfree(buf_new);
#endif
return err;
}
/**
* 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;
}
/**
* 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 - 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;
/*
* Deliberately corrupt the buffer to improve robustness. Indeed, if we
* do not do this, the following may happen:
* 1. The buffer contains data from previous operation, e.g., read from
* another PEB previously. The data looks like expected, e.g., if we
* just do not read anything and return - the caller would not
* notice this. E.g., if we are reading a VID header, the buffer may
* contain a valid VID header from another PEB.
* 2. The driver is buggy and returns us success or -EBADMSG or
* -EUCLEAN, but it does not actually put any data to the buffer.
*
* This may confuse UBI or upper layers - they may think the buffer
* contains valid data while in fact it is just old data. This is
* especially possible because UBI (and UBIFS) relies on CRC, and
* treats data as correct even in case of ECC errors if the CRC is
* correct.
*
* Try to prevent this situation by changing the first byte of the
* buffer.
*/
*((uint8_t *)buf) ^= 0xFF;
addr = (loff_t)pnum * ubi->peb_size + offset;
retry:
err = mtd_read(ubi->mtd, addr, len, &read, buf);
if (err) {
const char *errstr = mtd_is_eccerr(err) ? " (ECC error)" : "";
if (mtd_is_bitflip(err)) {
/*
* -EUCLEAN is reported if there was a bit-flip which
* was corrected, so this is harmless.
*
* We do not report about it here unless debugging is
* enabled. A corresponding message will be printed
* later, when it is has been scrubbed.
*/
dbg_msg("fixable bit-flip detected at PEB %d", pnum);
ubi_assert(len == read);
return UBI_IO_BITFLIPS;
}
if (retries++ < UBI_IO_RETRIES) {
dbg_io("error %d%s while reading %d bytes from PEB "
"%d:%d, read only %zd bytes, retry",
err, errstr, len, pnum, offset, read);
yield();
goto retry;
}
ubi_err("error %d%s while reading %d bytes from PEB %d:%d, "
"read %zd bytes", err, errstr, 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 && mtd_is_eccerr(err)) {
ubi_assert(0);
err = -EIO;
}
} else {
ubi_assert(len == read);
if (ubi_dbg_is_bitflip(ubi)) {
dbg_gen("bit-flip (emulated)");
err = UBI_IO_BITFLIPS;
}
}
return err;
}
