UBI: Fastmap: Locking updates
a) Rename ubi->fm_sem to ubi->fm_eba_sem as this semaphore protects EBA changes. b) Turn ubi->fm_mutex into a rw semaphore. It will still serialize fastmap writes but also ensures that ubi_wl_put_peb() is not interrupted by a fastmap write. We use a rw semaphore to allow ubi_wl_put_peb() still to be executed in parallel if no fastmap write is happening. Signed-off-by: Richard Weinberger <richard@nod.at>
This commit is contained in:
parent
42dd3cdcd6
commit
111ab0b26f
|
@ -969,8 +969,8 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
|
|||
mutex_init(&ubi->ckvol_mutex);
|
||||
mutex_init(&ubi->device_mutex);
|
||||
spin_lock_init(&ubi->volumes_lock);
|
||||
mutex_init(&ubi->fm_mutex);
|
||||
init_rwsem(&ubi->fm_sem);
|
||||
init_rwsem(&ubi->fm_protect);
|
||||
init_rwsem(&ubi->fm_eba_sem);
|
||||
|
||||
ubi_msg(ubi, "attaching mtd%d", mtd->index);
|
||||
|
||||
|
|
|
@ -340,9 +340,9 @@ int ubi_eba_unmap_leb(struct ubi_device *ubi, struct ubi_volume *vol,
|
|||
|
||||
dbg_eba("erase LEB %d:%d, PEB %d", vol_id, lnum, pnum);
|
||||
|
||||
down_read(&ubi->fm_sem);
|
||||
down_read(&ubi->fm_eba_sem);
|
||||
vol->eba_tbl[lnum] = UBI_LEB_UNMAPPED;
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
err = ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 0);
|
||||
|
||||
out_unlock:
|
||||
|
@ -567,7 +567,7 @@ retry:
|
|||
new_pnum = ubi_wl_get_peb(ubi);
|
||||
if (new_pnum < 0) {
|
||||
ubi_free_vid_hdr(ubi, vid_hdr);
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
return new_pnum;
|
||||
}
|
||||
|
||||
|
@ -578,14 +578,14 @@ retry:
|
|||
if (err && err != UBI_IO_BITFLIPS) {
|
||||
if (err > 0)
|
||||
err = -EIO;
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
goto out_put;
|
||||
}
|
||||
|
||||
vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
|
||||
err = ubi_io_write_vid_hdr(ubi, new_pnum, vid_hdr);
|
||||
if (err) {
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
goto write_error;
|
||||
}
|
||||
|
||||
|
@ -597,7 +597,7 @@ retry:
|
|||
if (offset > 0) {
|
||||
err = ubi_io_read_data(ubi, ubi->peb_buf, pnum, 0, offset);
|
||||
if (err && err != UBI_IO_BITFLIPS) {
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
goto out_unlock;
|
||||
}
|
||||
}
|
||||
|
@ -607,7 +607,7 @@ retry:
|
|||
err = ubi_io_write_data(ubi, ubi->peb_buf, new_pnum, 0, data_size);
|
||||
if (err) {
|
||||
mutex_unlock(&ubi->buf_mutex);
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
goto write_error;
|
||||
}
|
||||
|
||||
|
@ -615,7 +615,7 @@ retry:
|
|||
ubi_free_vid_hdr(ubi, vid_hdr);
|
||||
|
||||
vol->eba_tbl[lnum] = new_pnum;
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 1);
|
||||
|
||||
ubi_msg(ubi, "data was successfully recovered");
|
||||
|
@ -710,7 +710,7 @@ retry:
|
|||
if (pnum < 0) {
|
||||
ubi_free_vid_hdr(ubi, vid_hdr);
|
||||
leb_write_unlock(ubi, vol_id, lnum);
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
return pnum;
|
||||
}
|
||||
|
||||
|
@ -721,7 +721,7 @@ retry:
|
|||
if (err) {
|
||||
ubi_warn(ubi, "failed to write VID header to LEB %d:%d, PEB %d",
|
||||
vol_id, lnum, pnum);
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
goto write_error;
|
||||
}
|
||||
|
||||
|
@ -730,13 +730,13 @@ retry:
|
|||
if (err) {
|
||||
ubi_warn(ubi, "failed to write %d bytes at offset %d of LEB %d:%d, PEB %d",
|
||||
len, offset, vol_id, lnum, pnum);
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
goto write_error;
|
||||
}
|
||||
}
|
||||
|
||||
vol->eba_tbl[lnum] = pnum;
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
|
||||
leb_write_unlock(ubi, vol_id, lnum);
|
||||
ubi_free_vid_hdr(ubi, vid_hdr);
|
||||
|
@ -833,7 +833,7 @@ retry:
|
|||
if (pnum < 0) {
|
||||
ubi_free_vid_hdr(ubi, vid_hdr);
|
||||
leb_write_unlock(ubi, vol_id, lnum);
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
return pnum;
|
||||
}
|
||||
|
||||
|
@ -844,7 +844,7 @@ retry:
|
|||
if (err) {
|
||||
ubi_warn(ubi, "failed to write VID header to LEB %d:%d, PEB %d",
|
||||
vol_id, lnum, pnum);
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
goto write_error;
|
||||
}
|
||||
|
||||
|
@ -852,13 +852,13 @@ retry:
|
|||
if (err) {
|
||||
ubi_warn(ubi, "failed to write %d bytes of data to PEB %d",
|
||||
len, pnum);
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
goto write_error;
|
||||
}
|
||||
|
||||
ubi_assert(vol->eba_tbl[lnum] < 0);
|
||||
vol->eba_tbl[lnum] = pnum;
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
|
||||
leb_write_unlock(ubi, vol_id, lnum);
|
||||
ubi_free_vid_hdr(ubi, vid_hdr);
|
||||
|
@ -953,7 +953,7 @@ retry:
|
|||
pnum = ubi_wl_get_peb(ubi);
|
||||
if (pnum < 0) {
|
||||
err = pnum;
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
goto out_leb_unlock;
|
||||
}
|
||||
|
||||
|
@ -964,7 +964,7 @@ retry:
|
|||
if (err) {
|
||||
ubi_warn(ubi, "failed to write VID header to LEB %d:%d, PEB %d",
|
||||
vol_id, lnum, pnum);
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
goto write_error;
|
||||
}
|
||||
|
||||
|
@ -972,13 +972,13 @@ retry:
|
|||
if (err) {
|
||||
ubi_warn(ubi, "failed to write %d bytes of data to PEB %d",
|
||||
len, pnum);
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
goto write_error;
|
||||
}
|
||||
|
||||
old_pnum = vol->eba_tbl[lnum];
|
||||
vol->eba_tbl[lnum] = pnum;
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
|
||||
if (old_pnum >= 0) {
|
||||
err = ubi_wl_put_peb(ubi, vol_id, lnum, old_pnum, 0);
|
||||
|
@ -1231,9 +1231,9 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
|
|||
}
|
||||
|
||||
ubi_assert(vol->eba_tbl[lnum] == from);
|
||||
down_read(&ubi->fm_sem);
|
||||
down_read(&ubi->fm_eba_sem);
|
||||
vol->eba_tbl[lnum] = to;
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
|
||||
out_unlock_buf:
|
||||
mutex_unlock(&ubi->buf_mutex);
|
||||
|
|
|
@ -800,7 +800,7 @@ int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
|
|||
__be32 crc, tmp_crc;
|
||||
unsigned long long sqnum = 0;
|
||||
|
||||
mutex_lock(&ubi->fm_mutex);
|
||||
down_write(&ubi->fm_protect);
|
||||
memset(ubi->fm_buf, 0, ubi->fm_size);
|
||||
|
||||
fmsb = kmalloc(sizeof(*fmsb), GFP_KERNEL);
|
||||
|
@ -991,7 +991,7 @@ int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
|
|||
ubi_free_vid_hdr(ubi, vh);
|
||||
kfree(ech);
|
||||
out:
|
||||
mutex_unlock(&ubi->fm_mutex);
|
||||
up_write(&ubi->fm_protect);
|
||||
if (ret == UBI_BAD_FASTMAP)
|
||||
ubi_err(ubi, "Attach by fastmap failed, doing a full scan!");
|
||||
return ret;
|
||||
|
@ -1340,24 +1340,24 @@ int ubi_update_fastmap(struct ubi_device *ubi)
|
|||
struct ubi_fastmap_layout *new_fm, *old_fm;
|
||||
struct ubi_wl_entry *tmp_e;
|
||||
|
||||
mutex_lock(&ubi->fm_mutex);
|
||||
down_write(&ubi->fm_protect);
|
||||
|
||||
ubi_refill_pools(ubi);
|
||||
|
||||
if (ubi->ro_mode || ubi->fm_disabled) {
|
||||
mutex_unlock(&ubi->fm_mutex);
|
||||
up_write(&ubi->fm_protect);
|
||||
return 0;
|
||||
}
|
||||
|
||||
ret = ubi_ensure_anchor_pebs(ubi);
|
||||
if (ret) {
|
||||
mutex_unlock(&ubi->fm_mutex);
|
||||
up_write(&ubi->fm_protect);
|
||||
return ret;
|
||||
}
|
||||
|
||||
new_fm = kzalloc(sizeof(*new_fm), GFP_KERNEL);
|
||||
if (!new_fm) {
|
||||
mutex_unlock(&ubi->fm_mutex);
|
||||
up_write(&ubi->fm_protect);
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
|
@ -1447,16 +1447,16 @@ int ubi_update_fastmap(struct ubi_device *ubi)
|
|||
}
|
||||
|
||||
down_write(&ubi->work_sem);
|
||||
down_write(&ubi->fm_sem);
|
||||
down_write(&ubi->fm_eba_sem);
|
||||
ret = ubi_write_fastmap(ubi, new_fm);
|
||||
up_write(&ubi->fm_sem);
|
||||
up_write(&ubi->fm_eba_sem);
|
||||
up_write(&ubi->work_sem);
|
||||
|
||||
if (ret)
|
||||
goto err;
|
||||
|
||||
out_unlock:
|
||||
mutex_unlock(&ubi->fm_mutex);
|
||||
up_write(&ubi->fm_protect);
|
||||
kfree(old_fm);
|
||||
return ret;
|
||||
|
||||
|
|
|
@ -426,10 +426,11 @@ struct ubi_debug_info {
|
|||
* @fm_pool: in-memory data structure of the fastmap pool
|
||||
* @fm_wl_pool: in-memory data structure of the fastmap pool used by the WL
|
||||
* sub-system
|
||||
* @fm_mutex: serializes ubi_update_fastmap() and protects @fm_buf
|
||||
* @fm_protect: serializes ubi_update_fastmap(), protects @fm_buf and makes sure
|
||||
* that critical sections cannot be interrupted by ubi_update_fastmap()
|
||||
* @fm_buf: vmalloc()'d buffer which holds the raw fastmap
|
||||
* @fm_size: fastmap size in bytes
|
||||
* @fm_sem: allows ubi_update_fastmap() to block EBA table changes
|
||||
* @fm_eba_sem: allows ubi_update_fastmap() to block EBA table changes
|
||||
* @fm_work: fastmap work queue
|
||||
* @fm_work_scheduled: non-zero if fastmap work was scheduled
|
||||
*
|
||||
|
@ -534,8 +535,8 @@ struct ubi_device {
|
|||
struct ubi_fastmap_layout *fm;
|
||||
struct ubi_fm_pool fm_pool;
|
||||
struct ubi_fm_pool fm_wl_pool;
|
||||
struct rw_semaphore fm_sem;
|
||||
struct mutex fm_mutex;
|
||||
struct rw_semaphore fm_eba_sem;
|
||||
struct rw_semaphore fm_protect;
|
||||
void *fm_buf;
|
||||
size_t fm_size;
|
||||
struct work_struct fm_work;
|
||||
|
|
|
@ -641,7 +641,7 @@ void ubi_refill_pools(struct ubi_device *ubi)
|
|||
|
||||
/* ubi_wl_get_peb - works exaclty like __wl_get_peb but keeps track of
|
||||
* the fastmap pool.
|
||||
* Returns with ubi->fm_sem held in read mode!
|
||||
* Returns with ubi->fm_eba_sem held in read mode!
|
||||
*/
|
||||
int ubi_wl_get_peb(struct ubi_device *ubi)
|
||||
{
|
||||
|
@ -650,20 +650,20 @@ int ubi_wl_get_peb(struct ubi_device *ubi)
|
|||
struct ubi_fm_pool *wl_pool = &ubi->fm_wl_pool;
|
||||
|
||||
again:
|
||||
down_read(&ubi->fm_sem);
|
||||
down_read(&ubi->fm_eba_sem);
|
||||
spin_lock(&ubi->wl_lock);
|
||||
/* We check here also for the WL pool because at this point we can
|
||||
* refill the WL pool synchronous. */
|
||||
if (pool->used == pool->size || wl_pool->used == wl_pool->size) {
|
||||
spin_unlock(&ubi->wl_lock);
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
ret = ubi_update_fastmap(ubi);
|
||||
if (ret) {
|
||||
ubi_msg(ubi, "Unable to write a new fastmap: %i", ret);
|
||||
down_read(&ubi->fm_sem);
|
||||
down_read(&ubi->fm_eba_sem);
|
||||
return -ENOSPC;
|
||||
}
|
||||
down_read(&ubi->fm_sem);
|
||||
down_read(&ubi->fm_eba_sem);
|
||||
spin_lock(&ubi->wl_lock);
|
||||
}
|
||||
|
||||
|
@ -675,7 +675,7 @@ again:
|
|||
goto out;
|
||||
}
|
||||
retried = 1;
|
||||
up_read(&ubi->fm_sem);
|
||||
up_read(&ubi->fm_eba_sem);
|
||||
goto again;
|
||||
}
|
||||
|
||||
|
@ -731,7 +731,7 @@ int ubi_wl_get_peb(struct ubi_device *ubi)
|
|||
spin_lock(&ubi->wl_lock);
|
||||
peb = wl_get_peb(ubi);
|
||||
spin_unlock(&ubi->wl_lock);
|
||||
down_read(&ubi->fm_sem);
|
||||
down_read(&ubi->fm_eba_sem);
|
||||
|
||||
if (peb < 0)
|
||||
return peb;
|
||||
|
@ -1607,6 +1607,8 @@ int ubi_wl_put_peb(struct ubi_device *ubi, int vol_id, int lnum,
|
|||
ubi_assert(pnum >= 0);
|
||||
ubi_assert(pnum < ubi->peb_count);
|
||||
|
||||
down_read(&ubi->fm_protect);
|
||||
|
||||
retry:
|
||||
spin_lock(&ubi->wl_lock);
|
||||
e = ubi->lookuptbl[pnum];
|
||||
|
@ -1637,6 +1639,7 @@ retry:
|
|||
ubi_assert(!ubi->move_to_put);
|
||||
ubi->move_to_put = 1;
|
||||
spin_unlock(&ubi->wl_lock);
|
||||
up_read(&ubi->fm_protect);
|
||||
return 0;
|
||||
} else {
|
||||
if (in_wl_tree(e, &ubi->used)) {
|
||||
|
@ -1658,6 +1661,7 @@ retry:
|
|||
ubi_err(ubi, "PEB %d not found", pnum);
|
||||
ubi_ro_mode(ubi);
|
||||
spin_unlock(&ubi->wl_lock);
|
||||
up_read(&ubi->fm_protect);
|
||||
return err;
|
||||
}
|
||||
}
|
||||
|
@ -1671,6 +1675,7 @@ retry:
|
|||
spin_unlock(&ubi->wl_lock);
|
||||
}
|
||||
|
||||
up_read(&ubi->fm_protect);
|
||||
return err;
|
||||
}
|
||||
|
||||
|
|
Loading…
Reference in a new issue