/**
* in_wl_tree - check if wear-leveling entry is present in a WL RB-tree.
* @e: the wear-leveling entry to check
* @root: the root of the tree
*
* This function returns non-zero if @e is in the @root RB-tree and zero if it
* is not.
*/
static int in_wl_tree(struct ubi_wl_entry *e, struct rb_root *root)
{
struct rb_node *p;
p = root->rb_node;
while (p) {
struct ubi_wl_entry *e1;
e1 = rb_entry(p, struct ubi_wl_entry, u.rb);
if (e->pnum == e1->pnum) {
ubi_assert(e == e1);
return 1;
}
if (e->ec < e1->ec)
p = p->rb_left;
else if (e->ec > e1->ec)
p = p->rb_right;
else {
ubi_assert(e->pnum != e1->pnum);
if (e->pnum < e1->pnum)
p = p->rb_left;
else
p = p->rb_right;
}
}
return 0;
}
/* 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 peb%d:0x%x, written ",
err, addr, pnum, offset);
dump_stack();
} else
ubi_assert(ops.retlen == ops.len);
return err;
}
/**
* ubi_remove_volume - remove volume.
* @desc: volume descriptor
* @no_vtbl: do not change volume table if not zero
*
* This function removes volume described by @desc. The volume has to be opened
* in "exclusive" mode. Returns zero in case of success and a negative error
* code in case of failure. The caller has to have the @ubi->device_mutex
* locked.
*/
int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl)
{
struct ubi_volume *vol = desc->vol;
struct ubi_device *ubi = vol->ubi;
int i, err, vol_id = vol->vol_id, reserved_pebs = vol->reserved_pebs;
dbg_gen("remove device %d, volume %d", ubi->ubi_num, vol_id);
ubi_assert(desc->mode == UBI_EXCLUSIVE);
ubi_assert(vol == ubi->volumes[vol_id]);
if (ubi->ro_mode)
return -EROFS;
if (vol->ref_count > 1) {
/*
* The volume is busy, probably someone is reading one of its
* sysfs files.
*/
err = -EBUSY;
goto out_unlock;
}
ubi->volumes[vol_id] = NULL;
if (!no_vtbl) {
err = ubi_change_vtbl_record(ubi, vol_id, NULL);
if (err)
goto out_err;
}
for (i = 0; i < vol->reserved_pebs; i++) {
err = ubi_eba_unmap_leb(ubi, vol, i);
if (err)
goto out_err;
}
unregister_device(&vol->dev);
devfs_remove(&vol->cdev);
ubi->rsvd_pebs -= reserved_pebs;
ubi->avail_pebs += reserved_pebs;
ubi_update_reserved(ubi);
ubi->vol_count -= 1;
ubi_volume_notify(ubi, vol, UBI_VOLUME_REMOVED);
if (!no_vtbl)
self_check_volumes(ubi);
return err;
out_err:
ubi_err(ubi, "cannot remove volume %d, error %d", vol_id, err);
ubi->volumes[vol_id] = vol;
out_unlock:
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();
} else {
ubi_assert(len == read);
if (ubi_dbg_is_bitflip()) {
dbg_msg("bit-flip (emulated)");
err = UBI_IO_BITFLIPS;
}
}
return err;
}
/* Read one page with oob one time */
int ubi_io_read_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_read_oob(ubi->mtd, addr, &ops);
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.
*/
ubi_msg("fixable bit-flip detected at addr %lld", addr);
if(oobbuf)
ubi_assert(ops.oobretlen == ops.ooblen);
return UBI_IO_BITFLIPS;
}
if (ops.retlen != ops.len && err == -EBADMSG) {
ubi_err("err(%d), retlen(%zu), len(%zu)", err, ops.retlen, ops.len);
dump_stack();
err = -EIO;
}
ubi_msg("mtd_read_oob err %d\n", err);
}
return err;
}
/**
* ltree_add_entry - add new entry to the lock tree.
* @ubi: UBI device description object
* @vol_id: volume ID
* @lnum: logical eraseblock number
*
* This function adds new entry for logical eraseblock (@vol_id, @lnum) to the
* lock tree. If such entry is already there, its usage counter is increased.
* Returns pointer to the lock tree entry or %-ENOMEM if memory allocation
* failed.
*/
static struct ubi_ltree_entry *ltree_add_entry(struct ubi_device *ubi,
int vol_id, int lnum)
{
struct ubi_ltree_entry *le, *le1, *le_free;
le = kmalloc(sizeof(struct ubi_ltree_entry), GFP_NOFS);
if (!le)
return ERR_PTR(-ENOMEM);
le->users = 0;
init_rwsem(&le->mutex);
le->vol_id = vol_id;
le->lnum = lnum;
spin_lock(&ubi->ltree_lock);
le1 = ltree_lookup(ubi, vol_id, lnum);
if (le1) {
/*
* This logical eraseblock is already locked. The newly
* allocated lock entry is not needed.
*/
le_free = le;
le = le1;
} else {
struct rb_node **p, *parent = NULL;
/*
* No lock entry, add the newly allocated one to the
* @ubi->ltree RB-tree.
*/
le_free = NULL;
p = &ubi->ltree.rb_node;
while (*p) {
parent = *p;
le1 = rb_entry(parent, struct ubi_ltree_entry, rb);
if (vol_id < le1->vol_id)
p = &(*p)->rb_left;
else if (vol_id > le1->vol_id)
p = &(*p)->rb_right;
else {
ubi_assert(lnum != le1->lnum);
if (lnum < le1->lnum)
p = &(*p)->rb_left;
else
p = &(*p)->rb_right;
}
}
rb_link_node(&le->rb, parent, p);
rb_insert_color(&le->rb, &ubi->ltree);
}
le->users += 1;
spin_unlock(&ubi->ltree_lock);
kfree(le_free);
return le;
}
/**
* 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);
ec_hdr->image_seq = cpu_to_be32(ubi->image_seq);
crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC);
ec_hdr->hdr_crc = cpu_to_be32(crc);
err = self_check_ec_hdr(ubi, pnum, ec_hdr);
if (err)
return err;
if (ubi_dbg_power_cut(ubi, POWER_CUT_EC_WRITE))
return -EROFS;
err = ubi_io_write(ubi, ec_hdr, pnum, 0, ubi->ec_hdr_alsize);
return err;
}
/**
* wl_tree_add - add a wear-leveling entry to a WL RB-tree.
* @e: the wear-leveling entry to add
* @root: the root of the tree
*
* Note, we use (erase counter, physical eraseblock number) pairs as keys in
* the @ubi->used and @ubi->free RB-trees.
*/
static void wl_tree_add(struct ubi_wl_entry *e, struct rb_root *root)
{
struct rb_node **p, *parent = NULL;
p = &root->rb_node;
while (*p) {
struct ubi_wl_entry *e1;
parent = *p;
e1 = rb_entry(parent, struct ubi_wl_entry, u.rb);
if (e->ec < e1->ec)
p = &(*p)->rb_left;
else if (e->ec > e1->ec)
p = &(*p)->rb_right;
else {
ubi_assert(e->pnum != e1->pnum);
if (e->pnum < e1->pnum)
p = &(*p)->rb_left;
else
p = &(*p)->rb_right;
}
}
rb_link_node(&e->u.rb, parent, p);
rb_insert_color(&e->u.rb, root);
}
/**
* 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);
ec_hdr->image_seq = cpu_to_be32(ubi->image_seq);
crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC);
ec_hdr->hdr_crc = cpu_to_be32(crc);
err = self_check_ec_hdr(ubi, pnum, ec_hdr);
if (err)
return err;
#ifdef CONFIG_PWR_LOSS_MTK_SPOH
PL_RESET_ON_CASE("NAND", "WRITE_EC_Header");
#endif
err = ubi_io_write(ubi, ec_hdr, pnum, 0, ubi->ec_hdr_alsize);
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 than 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 = self_check_not_bad(ubi, pnum);
if (err != 0)
return err;
if (ubi->ro_mode) {
ubi_err(ubi, "read-only mode");
return -EROFS;
}
if (ubi->nor_flash) {
err = nor_erase_prepare(ubi, pnum);
if (err)
return err;
}
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_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 = self_check_peb_ec_hdr(ubi, pnum);
if (err)
return 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 = self_check_vid_hdr(ubi, pnum, vid_hdr);
if (err)
return err;
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;
}
/**
* ubi_io_write_vid_hdr - write a volume identifier header.
* @ubi: UBI device description object
* @pnum: the physical eraseblock number to write to
* @vidb: the volume identifier buffer to write
*
* This function writes the volume identifier header described by @vid_hdr to
* physical eraseblock @pnum. This function automatically fills the
* @vidb->hdr->magic and the @vidb->hdr->version fields, as well as calculates
* header CRC checksum and stores it at vidb->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_io_buf *vidb)
{
struct ubi_vid_hdr *vid_hdr = ubi_get_vid_hdr(vidb);
int err;
uint32_t crc;
void *p = vidb->buffer;
dbg_io("write VID header to PEB %d", pnum);
ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
err = self_check_peb_ec_hdr(ubi, pnum);
if (err)
return 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 = self_check_vid_hdr(ubi, pnum, vid_hdr);
if (err)
return err;
if (ubi_dbg_power_cut(ubi, POWER_CUT_VID_WRITE))
return -EROFS;
err = ubi_io_write(ubi, p, pnum, ubi->vid_hdr_aloffset,
ubi->vid_hdr_alsize);
return err;
}
/**
* clear_update_marker - clear update marker.
* @ubi: UBI device description object
* @vol: volume description object
* @bytes: new data size in bytes
*
* This function clears the update marker for volume @vol, sets new volume
* data size and clears the "corrupted" flag (static volumes only). Returns
* zero in case of success and a negative error code in case of failure.
*/
static int clear_update_marker(struct ubi_device *ubi, struct ubi_volume *vol,
long long bytes)
{
int err;
uint64_t tmp;
struct ubi_vtbl_record vtbl_rec;
dbg_msg("clear update marker for volume %d", vol->vol_id);
memcpy(&vtbl_rec, &ubi->vtbl[vol->vol_id],
sizeof(struct ubi_vtbl_record));
ubi_assert(vol->upd_marker && vtbl_rec.upd_marker);
vtbl_rec.upd_marker = 0;
if (vol->vol_type == UBI_STATIC_VOLUME) {
vol->corrupted = 0;
vol->used_bytes = tmp = bytes;
vol->last_eb_bytes = do_div(tmp, vol->usable_leb_size);
vol->used_ebs = tmp;
if (vol->last_eb_bytes)
vol->used_ebs += 1;
else
vol->last_eb_bytes = vol->usable_leb_size;
}
mutex_lock(&ubi->volumes_mutex);
err = ubi_change_vtbl_record(ubi, vol->vol_id, &vtbl_rec);
mutex_unlock(&ubi->volumes_mutex);
vol->upd_marker = 0;
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_change_vtbl_record - change volume table record.
* @ubi: UBI device description object
* @idx: table index to change
* @vtbl_rec: new volume table record
*
* This function changes volume table record @idx. If @vtbl_rec is %NULL, empty
* volume table record is written. The caller does not have to calculate CRC of
* the record as it is done by this function. Returns zero in case of success
* and a negative error code in case of failure.
*/
int ubi_change_vtbl_record(struct ubi_device *ubi, int idx,
struct ubi_vtbl_record *vtbl_rec)
{
int i, err;
uint32_t crc;
struct ubi_volume *layout_vol;
ubi_assert(idx >= 0 && idx < ubi->vtbl_slots);
layout_vol = ubi->volumes[vol_id2idx(ubi, UBI_LAYOUT_VOLUME_ID)];
if (!vtbl_rec)
vtbl_rec = &empty_vtbl_record;
else {
crc = crc32(UBI_CRC32_INIT, vtbl_rec, UBI_VTBL_RECORD_SIZE_CRC);
vtbl_rec->crc = cpu_to_be32(crc);
}
memcpy(&ubi->vtbl[idx], vtbl_rec, sizeof(struct ubi_vtbl_record));
for (i = 0; i < UBI_LAYOUT_VOLUME_EBS; i++) {
err = ubi_eba_unmap_leb(ubi, layout_vol, i);
if (err)
return err;
err = ubi_eba_write_leb(ubi, layout_vol, i, ubi->vtbl, 0,
ubi->vtbl_size);
if (err)
return err;
}
self_vtbl_check(ubi);
return 0;
}
/**
* clear_update_marker - clear update marker.
* @ubi: UBI device description object
* @vol: volume description object
* @bytes: new data size in bytes
*
* This function clears the update marker for volume @vol, sets new volume
* data size and clears the "corrupted" flag (static volumes only). Returns
* zero in case of success and a negative error code in case of failure.
*/
static int clear_update_marker(struct ubi_device *ubi, struct ubi_volume *vol,
long long bytes)
{
int err;
struct ubi_vtbl_record vtbl_rec;
dbg_gen("clear update marker for volume %d", vol->vol_id);
vtbl_rec = ubi->vtbl[vol->vol_id];
ubi_assert(vol->upd_marker && vtbl_rec.upd_marker);
vtbl_rec.upd_marker = 0;
if (vol->vol_type == UBI_STATIC_VOLUME) {
vol->corrupted = 0;
vol->used_bytes = bytes;
vol->used_ebs = div_u64_rem(bytes, vol->usable_leb_size,
&vol->last_eb_bytes);
if (vol->last_eb_bytes)
vol->used_ebs += 1;
else
vol->last_eb_bytes = vol->usable_leb_size;
}
mutex_lock(&ubi->device_mutex);
err = ubi_change_vtbl_record(ubi, vol->vol_id, &vtbl_rec);
vol->upd_marker = 0;
mutex_unlock(&ubi->device_mutex);
return err;
}
/**
* nor_erase_prepare - prepare a NOR flash PEB for erasure.
* @ubi: UBI device description object
* @pnum: physical eraseblock number to prepare
*
* NOR flash, or at least some of them, have peculiar embedded PEB erasure
* algorithm: the PEB is first filled with zeroes, then it is erased. And
* filling with zeroes starts from the end of the PEB. This was observed with
* Spansion S29GL512N NOR flash.
*
* This means that in case of a power cut we may end up with intact data at the
* beginning of the PEB, and all zeroes at the end of PEB. In other words, the
* EC and VID headers are OK, but a large chunk of data at the end of PEB is
* zeroed. This makes UBI mistakenly treat this PEB as used and associate it
* with an LEB, which leads to subsequent failures (e.g., UBIFS fails).
*
* This function is called before erasing NOR PEBs and it zeroes out EC and VID
* magic numbers in order to invalidate them and prevent the failures. Returns
* zero in case of success and a negative error code in case of failure.
*/
static int nor_erase_prepare(struct ubi_device *ubi, int pnum)
{
int err;
size_t written;
loff_t addr;
uint32_t data = 0;
struct ubi_ec_hdr ec_hdr;
struct ubi_vid_io_buf vidb;
/*
* Note, we cannot generally define VID header buffers on stack,
* because of the way we deal with these buffers (see the header
* comment in this file). But we know this is a NOR-specific piece of
* code, so we can do this. But yes, this is error-prone and we should
* (pre-)allocate VID header buffer instead.
*/
struct ubi_vid_hdr vid_hdr;
/*
* If VID or EC is valid, we have to corrupt them before erasing.
* It is important to first invalidate the EC header, and then the VID
* header. Otherwise a power cut may lead to valid EC header and
* invalid VID header, in which case UBI will treat this PEB as
* corrupted and will try to preserve it, and print scary warnings.
*/
addr = (loff_t)pnum * ubi->peb_size;
err = ubi_io_read_ec_hdr(ubi, pnum, &ec_hdr, 0);
if (err != UBI_IO_BAD_HDR_EBADMSG && err != UBI_IO_BAD_HDR &&
err != UBI_IO_FF){
err = mtd_write(ubi->mtd, addr, 4, &written, (void *)&data);
if(err)
goto error;
}
ubi_init_vid_buf(ubi, &vidb, &vid_hdr);
ubi_assert(&vid_hdr == ubi_get_vid_hdr(&vidb));
err = ubi_io_read_vid_hdr(ubi, pnum, &vidb, 0);
if (err != UBI_IO_BAD_HDR_EBADMSG && err != UBI_IO_BAD_HDR &&
err != UBI_IO_FF){
addr += ubi->vid_hdr_aloffset;
err = mtd_write(ubi->mtd, addr, 4, &written, (void *)&data);
if (err)
goto error;
}
return 0;
error:
/*
* The PEB contains a valid VID or EC header, but we cannot invalidate
* it. Supposedly the flash media or the driver is screwed up, so
* return an error.
*/
ubi_err(ubi, "cannot invalidate PEB %d, write returned %d", pnum, err);
ubi_dump_flash(ubi, pnum, 0, ubi->peb_size);
return -EIO;
}
/**
* revoke_exclusive - revoke exclusive mode.
* @desc: volume descriptor
* @mode: new mode to switch to
*/
static void revoke_exclusive(struct ubi_volume_desc *desc, int mode)
{
struct ubi_volume *vol = desc->vol;
spin_lock(&vol->ubi->volumes_lock);
ubi_assert(vol->readers == 0 && vol->writers == 0);
ubi_assert(vol->exclusive == 1 && desc->mode == UBI_EXCLUSIVE);
vol->exclusive = 0;
if (mode == UBI_READONLY)
vol->readers = 1;
else if (mode == UBI_READWRITE)
vol->writers = 1;
else
vol->exclusive = 1;
spin_unlock(&vol->ubi->volumes_lock);
desc->mode = mode;
}
/**
* prot_queue_add - add physical eraseblock to the protection queue.
* @ubi: UBI device description object
* @e: the physical eraseblock to add
*
* This function adds @e to the tail of the protection queue @ubi->pq, where
* @e will stay for %UBI_PROT_QUEUE_LEN erase operations and will be
* temporarily protected from the wear-leveling worker. Note, @wl->lock has to
* be locked.
*/
static void prot_queue_add(struct ubi_device *ubi, struct ubi_wl_entry *e)
{
int pq_tail = ubi->pq_head - 1;
if (pq_tail < 0)
pq_tail = UBI_PROT_QUEUE_LEN - 1;
ubi_assert(pq_tail >= 0 && pq_tail < UBI_PROT_QUEUE_LEN);
list_add_tail(&e->u.list, &ubi->pq[pq_tail]);
dbg_wl("added PEB %d EC %d to the protection queue", e->pnum, e->ec);
}
/**
* gluebi_put_device - put MTD device reference.
* @mtd: the MTD device description object
*
* This function is called every time the MTD device is being put. Returns
* zero in case of success and a negative error code in case of failure.
*/
static void gluebi_put_device(struct mtd_info *mtd)
{
struct ubi_volume *vol;
vol = container_of(mtd, struct ubi_volume, gluebi_mtd);
vol->gluebi_refcount -= 1;
ubi_assert(vol->gluebi_refcount >= 0);
if (vol->gluebi_refcount == 0)
ubi_close_volume(vol->gluebi_desc);
}
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;
}
/**
* leb_write_unlock - unlock logical eraseblock.
* @ubi: UBI device description object
* @vol_id: volume ID
* @lnum: logical eraseblock number
*/
static void leb_write_unlock(struct ubi_device *ubi, int vol_id, int lnum)
{
struct ubi_ltree_entry *le;
spin_lock(&ubi->ltree_lock);
le = ltree_lookup(ubi, vol_id, lnum);
le->users -= 1;
ubi_assert(le->users >= 0);
up_write(&le->mutex);
if (le->users == 0) {
rb_erase(&le->rb, &ubi->ltree);
kfree(le);
}
spin_unlock(&ubi->ltree_lock);
}
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;
length = ALIGN(i + 1, ubi->min_io_size);
return length;
}
/**
* add_volume - add volume to the scanning information.
* @si: scanning information
* @vol_id: ID of the volume to add
* @pnum: physical eraseblock number
* @vid_hdr: volume identifier header
*
* If the volume corresponding to the @vid_hdr logical eraseblock is already
* present in the scanning information, this function does nothing. Otherwise
* it adds corresponding volume to the scanning information. Returns a pointer
* to the scanning volume object in case of success and a negative error code
* in case of failure.
*/
static struct ubi_scan_volume *add_volume(struct ubi_scan_info *si, int vol_id,
int pnum,
const struct ubi_vid_hdr *vid_hdr)
{
struct ubi_scan_volume *sv;
struct rb_node **p = &si->volumes.rb_node, *parent = NULL;
ubi_assert(vol_id == be32_to_cpu(vid_hdr->vol_id));
/* Walk the volume RB-tree to look if this volume is already present */
while (*p) {
parent = *p;
sv = rb_entry(parent, struct ubi_scan_volume, rb);
if (vol_id == sv->vol_id)
return sv;
if (vol_id > sv->vol_id)
p = &(*p)->rb_left;
else
p = &(*p)->rb_right;
}
/* The volume is absent - add it */
sv = kmalloc(sizeof(struct ubi_scan_volume), GFP_KERNEL);
if (!sv)
return ERR_PTR(-ENOMEM);
sv->highest_lnum = sv->leb_count = 0;
sv->vol_id = vol_id;
sv->root = RB_ROOT;
sv->used_ebs = be32_to_cpu(vid_hdr->used_ebs);
sv->data_pad = be32_to_cpu(vid_hdr->data_pad);
sv->compat = vid_hdr->compat;
sv->vol_type = vid_hdr->vol_type == UBI_VID_DYNAMIC ? UBI_DYNAMIC_VOLUME
: UBI_STATIC_VOLUME;
if (vol_id > si->highest_vol_id)
si->highest_vol_id = vol_id;
rb_link_node(&sv->rb, parent, p);
rb_insert_color(&sv->rb, &si->volumes);
si->vols_found += 1;
dbg_bld("added volume %d", vol_id);
return sv;
}
/**
* ubi_start_update - start volume update.
* @ubi: UBI device description object
* @vol: volume description object
* @bytes: update bytes
*
* This function starts volume update operation. If @bytes is zero, the volume
* is just wiped out. Returns zero in case of success and a negative error code
* in case of failure.
*/
int ubi_start_update(struct ubi_device *ubi, struct ubi_volume *vol,
long long bytes)
{
int i, err;
dbg_gen("start update of volume %d, %llu bytes", vol->vol_id, bytes);
ubi_assert(!vol->updating && !vol->changing_leb);
vol->updating = 1;
vol->upd_buf = vmalloc(ubi->leb_size);
if (!vol->upd_buf)
return -ENOMEM;
err = set_update_marker(ubi, vol);
if (err)
return err;
/* Before updating - wipe out the volume */
for (i = 0; i < vol->reserved_pebs; i++) {
err = ubi_eba_unmap_leb(ubi, vol, i);
if (err)
return err;
}
if (bytes == 0) {
err = ubi_wl_flush(ubi, UBI_ALL, UBI_ALL);
if (err)
return err;
err = clear_update_marker(ubi, vol, 0);
if (err)
return err;
vfree(vol->upd_buf);
vol->updating = 0;
return 0;
}
vol->upd_ebs = div_u64(bytes + vol->usable_leb_size - 1,
vol->usable_leb_size);
vol->upd_bytes = bytes;
vol->upd_received = 0;
return 0;
}
/**
* ubi_change_vtbl_record - change volume table record.
* @ubi: UBI device description object
* @idx: table index to change
* @vtbl_rec: new volume table record
*
* This function changes volume table record @idx. If @vtbl_rec is %NULL, empty
* volume table record is written. The caller does not have to calculate CRC of
* the record as it is done by this function. Returns zero in case of success
* and a negative error code in case of failure.
*/
int ubi_change_vtbl_record(struct ubi_device *ubi, int idx,
struct ubi_vtbl_record *vtbl_rec)
{
int i, err;
uint32_t crc;
struct ubi_volume *layout_vol;
ubi_assert(idx >= 0 && idx < ubi->vtbl_slots);
layout_vol = ubi->volumes[vol_id2idx(ubi, UBI_LAYOUT_VOLUME_ID)];
if (!vtbl_rec)
vtbl_rec = &empty_vtbl_record;
else {
crc = crc32(UBI_CRC32_INIT, vtbl_rec, UBI_VTBL_RECORD_SIZE_CRC);
vtbl_rec->crc = cpu_to_be32(crc);
}
memcpy(&ubi->vtbl[idx], vtbl_rec, sizeof(struct ubi_vtbl_record));
for (i = 0; i < UBI_LAYOUT_VOLUME_EBS; i++) {
err = ubi_eba_unmap_leb(ubi, layout_vol, i);
if (err)
return err;
#ifdef CONFIG_PWR_LOSS_MTK_SPOH
if(i==0)
{
PL_RESET_ON_CASE("NAND", "CreateVol_1");
}
else if(i==1)
{
PL_RESET_ON_CASE("NAND", "CreateVol_2");
}
#endif
err = ubi_eba_write_leb(ubi, layout_vol, i, ubi->vtbl, 0,
ubi->vtbl_size);
if (err)
return err;
}
paranoid_vtbl_check(ubi);
return 0;
}
/**
* set_update_marker - set update marker.
* @ubi: UBI device description object
* @vol: volume description object
*
* This function sets the update marker flag for volume @vol. Returns zero
* in case of success and a negative error code in case of failure.
*/
static int set_update_marker(struct ubi_device *ubi, struct ubi_volume *vol)
{
int err;
struct ubi_vtbl_record vtbl_rec;
dbg_gen("set update marker for volume %d", vol->vol_id);
if (vol->upd_marker) {
ubi_assert(ubi->vtbl[vol->vol_id].upd_marker);
dbg_gen("already set");
return 0;
}
vtbl_rec = ubi->vtbl[vol->vol_id];
vtbl_rec.upd_marker = 1;
err = ubi_change_vtbl_record(ubi, vol->vol_id, &vtbl_rec);
vol->upd_marker = 1;
return err;
}
/**
* 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(ubi, "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(ubi, "cannot mark PEB %d bad, error %d", pnum, err);
return err;
}
/**
* 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(ubi, "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_more_leb_change_data - accept more data for atomic LEB change.
* @ubi: UBI device description object
* @vol: volume description object
* @buf: write data (user-space memory buffer)
* @count: how much bytes to write
*
* This function accepts more data to the volume which is being under the
* "atomic LEB change" operation. It may be called arbitrary number of times
* until all data arrives. This function returns %0 in case of success, number
* of bytes written during the last call if the whole "atomic LEB change"
* operation has been successfully finished, and a negative error code in case
* of failure.
*/
int ubi_more_leb_change_data(struct ubi_device *ubi, struct ubi_volume *vol,
const void __user *buf, int count)
{
int err;
dbg_gen("write %d of %lld bytes, %lld already passed",
count, vol->upd_bytes, vol->upd_received);
if (ubi->ro_mode)
return -EROFS;
if (vol->upd_received + count > vol->upd_bytes)
count = vol->upd_bytes - vol->upd_received;
err = copy_from_user(vol->upd_buf + vol->upd_received, buf, count);
if (err)
return -EFAULT;
vol->upd_received += count;
if (vol->upd_received == vol->upd_bytes) {
int len = ALIGN((int)vol->upd_bytes, ubi->min_io_size);
memset(vol->upd_buf + vol->upd_bytes, 0xFF,
len - vol->upd_bytes);
len = ubi_calc_data_len(ubi, vol->upd_buf, len);
err = ubi_eba_atomic_leb_change(ubi, vol, vol->ch_lnum,
vol->upd_buf, len);
if (err)
return err;
}
ubi_assert(vol->upd_received <= vol->upd_bytes);
if (vol->upd_received == vol->upd_bytes) {
vol->changing_leb = 0;
err = count;
vfree(vol->upd_buf);
}
return err;
}
