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path: root/drivers/mtd/ubi/wl.c
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Diffstat (limited to 'drivers/mtd/ubi/wl.c')
-rw-r--r--drivers/mtd/ubi/wl.c45
1 files changed, 38 insertions, 7 deletions
diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
index 793882ba2a6e..9d1d3595a240 100644
--- a/drivers/mtd/ubi/wl.c
+++ b/drivers/mtd/ubi/wl.c
@@ -55,8 +55,8 @@
*
* As it was said, for the UBI sub-system all physical eraseblocks are either
* "free" or "used". Free eraseblock are kept in the @wl->free RB-tree, while
- * used eraseblocks are kept in @wl->used or @wl->scrub RB-trees, or
- * (temporarily) in the @wl->pq queue.
+ * used eraseblocks are kept in @wl->used, @wl->erroneous, or @wl->scrub
+ * RB-trees, as well as (temporarily) in the @wl->pq queue.
*
* When the WL sub-system returns a physical eraseblock, the physical
* eraseblock is protected from being moved for some "time". For this reason,
@@ -83,6 +83,8 @@
* used. The former state corresponds to the @wl->free tree. The latter state
* is split up on several sub-states:
* o the WL movement is allowed (@wl->used tree);
+ * o the WL movement is disallowed (@wl->erroneous) becouse the PEB is
+ * erroneous - e.g., there was a read error;
* o the WL movement is temporarily prohibited (@wl->pq queue);
* o scrubbing is needed (@wl->scrub tree).
*
@@ -653,7 +655,7 @@ static int schedule_erase(struct ubi_device *ubi, struct ubi_wl_entry *e,
static int wear_leveling_worker(struct ubi_device *ubi, struct ubi_work *wrk,
int cancel)
{
- int err, scrubbing = 0, torture = 0, protect = 0;
+ int err, scrubbing = 0, torture = 0, protect = 0, erroneous = 0;
struct ubi_wl_entry *e1, *e2;
struct ubi_vid_hdr *vid_hdr;
@@ -769,13 +771,31 @@ static int wear_leveling_worker(struct ubi_device *ubi, struct ubi_work *wrk,
goto out_not_moved;
}
- if (err == MOVE_CANCEL_BITFLIPS ||
- err == MOVE_TARGET_WR_ERR) {
+ if (err == MOVE_CANCEL_BITFLIPS || err == MOVE_TARGET_WR_ERR ||
+ err == MOVE_TARGET_RD_ERR) {
/* Target PEB bit-flips or write error, torture it */
torture = 1;
goto out_not_moved;
}
+ if (err == MOVE_SOURCE_RD_ERR) {
+ /*
+ * An error happened while reading the source PEB. Do
+ * not switch to R/O mode in this case, and give the
+ * upper layers a possibility to recover from this,
+ * e.g. by unmapping corresponding LEB. Instead, just
+ * put thie PEB to the @ubi->erroneus list to prevent
+ * UBI from trying to move the over and over again.
+ */
+ if (ubi->erroneous_peb_count > ubi->max_erroneous) {
+ ubi_err("too many erroneous eraseblocks (%d)",
+ ubi->erroneous_peb_count);
+ goto out_error;
+ }
+ erroneous = 1;
+ goto out_not_moved;
+ }
+
if (err < 0)
goto out_error;
@@ -832,7 +852,10 @@ out_not_moved:
spin_lock(&ubi->wl_lock);
if (protect)
prot_queue_add(ubi, e1);
- else if (scrubbing)
+ else if (erroneous) {
+ wl_tree_add(e1, &ubi->erroneous);
+ ubi->erroneous_peb_count += 1;
+ } else if (scrubbing)
wl_tree_add(e1, &ubi->scrub);
else
wl_tree_add(e1, &ubi->used);
@@ -1116,6 +1139,13 @@ retry:
} else if (in_wl_tree(e, &ubi->scrub)) {
paranoid_check_in_wl_tree(e, &ubi->scrub);
rb_erase(&e->u.rb, &ubi->scrub);
+ } else if (in_wl_tree(e, &ubi->erroneous)) {
+ paranoid_check_in_wl_tree(e, &ubi->erroneous);
+ rb_erase(&e->u.rb, &ubi->erroneous);
+ ubi->erroneous_peb_count -= 1;
+ ubi_assert(ubi->erroneous_peb_count >= 0);
+ /* Erronious PEBs should be tortured */
+ torture = 1;
} else {
err = prot_queue_del(ubi, e->pnum);
if (err) {
@@ -1364,7 +1394,7 @@ int ubi_wl_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si)
struct ubi_scan_leb *seb, *tmp;
struct ubi_wl_entry *e;
- ubi->used = ubi->free = ubi->scrub = RB_ROOT;
+ ubi->used = ubi->erroneous = ubi->free = ubi->scrub = RB_ROOT;
spin_lock_init(&ubi->wl_lock);
mutex_init(&ubi->move_mutex);
init_rwsem(&ubi->work_sem);
@@ -1502,6 +1532,7 @@ void ubi_wl_close(struct ubi_device *ubi)
cancel_pending(ubi);
protection_queue_destroy(ubi);
tree_destroy(&ubi->used);
+ tree_destroy(&ubi->erroneous);
tree_destroy(&ubi->free);
tree_destroy(&ubi->scrub);
kfree(ubi->lookuptbl);