/**
* 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_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;
}
/**
* 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_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);
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 */
if (verbose)
ubi_warn("no EC header found at PEB %d, "
"only 0xFF bytes", pnum);
else if (UBI_IO_DEBUG)
dbg_msg("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);
} else if (UBI_IO_DEBUG)
dbg_msg("bad magic number at PEB %d: %08x instead of "
"%08x", pnum, magic, UBI_EC_HDR_MAGIC);
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);
} else if (UBI_IO_DEBUG)
dbg_msg("bad EC header CRC at PEB %d, calculated "
"%#08x, read %#08x", pnum, crc, hdr_crc);
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_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_HDR if the erase counter header is corrupted (a CRC error);
* o %UBI_IO_BAD_HDR_EBADMSG is the same as %UBI_IO_BAD_HDR, but there also was
* a data integrity error (uncorrectable ECC error in case of NAND);
* o %UBI_IO_FF if only 0xFF bytes were read (the PEB is supposedly 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;
uint32_t crc, magic, hdr_crc;
dbg_io("read EC header from PEB %d", pnum);
ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
read_err = ubi_io_read(ubi, ec_hdr, pnum, 0, UBI_EC_HDR_SIZE);
if (read_err) {
if (read_err != UBI_IO_BITFLIPS && !mtd_is_eccerr(read_err))
return read_err;
/*
* We read all the data, but either a correctable bit-flip
* occurred, or MTD reported a data integrity error
* (uncorrectable 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, to force scrubbing.
*/
}
magic = be32_to_cpu(ec_hdr->magic);
if (magic != UBI_EC_HDR_MAGIC) {
if (mtd_is_eccerr(read_err))
return UBI_IO_BAD_HDR_EBADMSG;
/*
* The magic field is wrong. Let's check if we have read all
* 0xFF. If yes, this physical eraseblock is assumed to be
* empty.
*/
if (ubi_check_pattern(ec_hdr, 0xFF, UBI_EC_HDR_SIZE)) {
/* The physical eraseblock is supposedly empty */
if (verbose)
ubi_warn("no EC header found at PEB %d, "
"only 0xFF bytes", pnum);
dbg_bld("no EC header found at PEB %d, "
"only 0xFF bytes", pnum);
if (!read_err)
return UBI_IO_FF;
else
return UBI_IO_FF_BITFLIPS;
}
/*
* 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);
}
dbg_bld("bad magic number at PEB %d: %08x instead of "
"%08x", pnum, magic, UBI_EC_HDR_MAGIC);
return UBI_IO_BAD_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);
}
dbg_bld("bad EC header CRC at PEB %d, calculated "
"%#08x, read %#08x", pnum, crc, hdr_crc);
if (!read_err)
return UBI_IO_BAD_HDR;
else
return UBI_IO_BAD_HDR_EBADMSG;
}
/* 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;
}
/*
* If there was %-EBADMSG, but the header CRC is still OK, report about
* a bit-flip to force scrubbing on this PEB.
*/
return read_err ? UBI_IO_BITFLIPS : 0;
}
