diff options
Diffstat (limited to 'drivers/mtd/ubi/misc.c')
-rw-r--r-- | drivers/mtd/ubi/misc.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/drivers/mtd/ubi/misc.c b/drivers/mtd/ubi/misc.c new file mode 100644 index 0000000000..1794d66b6e --- /dev/null +++ b/drivers/mtd/ubi/misc.c @@ -0,0 +1,191 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) International Business Machines Corp., 2006 + * + * Author: Artem Bityutskiy (Битюцкий Артём) + */ + +/* Here we keep miscellaneous functions which are used all over the UBI code */ + +#include "ubi.h" + +/** + * ubi_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; + + cond_resched(); + + 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 (mtd_is_eccerr(err)) + err = 1; + break; + } + } + + vfree(buf); + return err; +} + +/** + * ubi_update_reserved - update bad eraseblock handling accounting data. + * @ubi: UBI device description object + * + * This function calculates the gap between current number of PEBs reserved for + * bad eraseblock handling and the required level of PEBs that must be + * reserved, and if necessary, reserves more PEBs to fill that gap, according + * to availability. Should be called with ubi->volumes_lock held. + */ +void ubi_update_reserved(struct ubi_device *ubi) +{ + int need = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs; + + if (need <= 0 || ubi->avail_pebs == 0) + return; + + need = min_t(int, need, ubi->avail_pebs); + ubi->avail_pebs -= need; + ubi->rsvd_pebs += need; + ubi->beb_rsvd_pebs += need; + ubi_msg(ubi, "reserved more %d PEBs for bad PEB handling", need); +} + +/** + * ubi_calculate_reserved - calculate how many PEBs must be reserved for bad + * eraseblock handling. + * @ubi: UBI device description object + */ +void ubi_calculate_reserved(struct ubi_device *ubi) +{ + /* + * Calculate the actual number of PEBs currently needed to be reserved + * for future bad eraseblock handling. + */ + ubi->beb_rsvd_level = ubi->bad_peb_limit - ubi->bad_peb_count; + if (ubi->beb_rsvd_level < 0) { + ubi->beb_rsvd_level = 0; + ubi_warn(ubi, "number of bad PEBs (%d) is above the expected limit (%d), not reserving any PEBs for bad PEB handling, will use available PEBs (if any)", + ubi->bad_peb_count, ubi->bad_peb_limit); + } +} + +/** + * ubi_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. + */ +int ubi_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; +} + +/* Normal UBI messages */ +void ubi_msg(const struct ubi_device *ubi, const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + va_start(args, fmt); + + vaf.fmt = fmt; + vaf.va = &args; + + pr_notice(UBI_NAME_STR "%d: %pV\n", ubi->ubi_num, &vaf); + + va_end(args); +} + +/* UBI warning messages */ +void ubi_warn(const struct ubi_device *ubi, const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + va_start(args, fmt); + + vaf.fmt = fmt; + vaf.va = &args; + + pr_warn(UBI_NAME_STR "%d warning: %ps: %pV\n", + ubi->ubi_num, __builtin_return_address(0), &vaf); + + va_end(args); +} + +/* UBI error messages */ +void ubi_err(const struct ubi_device *ubi, const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + va_start(args, fmt); + + vaf.fmt = fmt; + vaf.va = &args; + + pr_err(UBI_NAME_STR "%d error: %ps: %pV\n", + ubi->ubi_num, __builtin_return_address(0), &vaf); + va_end(args); +} |