UBI: fix error handling in erase worker

Do not switch to read-only mode in case of -EINTR and some
other obvious cases. Switch to RO mode only when we do not
know what is the error.

Reported-by: Vinit Agnihotri <vinit.agnihotri@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
index d512cf1..9de9537 100644 (file)
--- a/drivers/mtd/ubi/wl.c
+++ b/drivers/mtd/ubi/wl.c
@@ -1060,9 +1060,8 @@ out_unlock:
 static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk,
                        int cancel)
 {
-       int err;
        struct ubi_wl_entry *e = wl_wrk->e;
-       int pnum = e->pnum;
+       int pnum = e->pnum, err, need;
 
        if (cancel) {
                dbg_wl("cancel erasure of PEB %d EC %d", pnum, e->ec);
@@ -1097,62 +1096,70 @@ static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk,
        kfree(wl_wrk);
        kmem_cache_free(wl_entries_slab, e);
 
-       if (err != -EIO) {
+       if (err == -EINTR || err == -ENOMEM || err == -EAGAIN ||
+           err == -EBUSY) {
+               int err1;
+
+               /* Re-schedule the LEB for erasure */
+               err1 = schedule_erase(ubi, e, 0);
+               if (err1) {
+                       err = err1;
+                       goto out_ro;
+               }
+               return err;
+       } else if (err != -EIO) {
                /*
                 * If this is not %-EIO, we have no idea what to do. Scheduling
                 * this physical eraseblock for erasure again would cause
                 * errors again and again. Well, lets switch to RO mode.
                 */
-               ubi_ro_mode(ubi);
-               return err;
+               goto out_ro;
        }
 
        /* It is %-EIO, the PEB went bad */
 
        if (!ubi->bad_allowed) {
                ubi_err("bad physical eraseblock %d detected", pnum);
-               ubi_ro_mode(ubi);
-               err = -EIO;
-       } else {
-               int need;
-
-               spin_lock(&ubi->volumes_lock);
-               need = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs + 1;
-               if (need > 0) {
-                       need = ubi->avail_pebs >= need ? need : ubi->avail_pebs;
-                       ubi->avail_pebs -= need;
-                       ubi->rsvd_pebs += need;
-                       ubi->beb_rsvd_pebs += need;
-                       if (need > 0)
-                               ubi_msg("reserve more %d PEBs", need);
-               }
+               goto out_ro;
+       }
 
-               if (ubi->beb_rsvd_pebs == 0) {
-                       spin_unlock(&ubi->volumes_lock);
-                       ubi_err("no reserved physical eraseblocks");
-                       ubi_ro_mode(ubi);
-                       return -EIO;
-               }
+       spin_lock(&ubi->volumes_lock);
+       need = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs + 1;
+       if (need > 0) {
+               need = ubi->avail_pebs >= need ? need : ubi->avail_pebs;
+               ubi->avail_pebs -= need;
+               ubi->rsvd_pebs += need;
+               ubi->beb_rsvd_pebs += need;
+               if (need > 0)
+                       ubi_msg("reserve more %d PEBs", need);
+       }
 
+       if (ubi->beb_rsvd_pebs == 0) {
                spin_unlock(&ubi->volumes_lock);
-               ubi_msg("mark PEB %d as bad", pnum);
+               ubi_err("no reserved physical eraseblocks");
+               goto out_ro;
+       }
 
-               err = ubi_io_mark_bad(ubi, pnum);
-               if (err) {
-                       ubi_ro_mode(ubi);
-                       return err;
-               }
+       spin_unlock(&ubi->volumes_lock);
+       ubi_msg("mark PEB %d as bad", pnum);
 
-               spin_lock(&ubi->volumes_lock);
-               ubi->beb_rsvd_pebs -= 1;
-               ubi->bad_peb_count += 1;
-               ubi->good_peb_count -= 1;
-               ubi_calculate_reserved(ubi);
-               if (ubi->beb_rsvd_pebs == 0)
-                       ubi_warn("last PEB from the reserved pool was used");
-               spin_unlock(&ubi->volumes_lock);
-       }
+       err = ubi_io_mark_bad(ubi, pnum);
+       if (err)
+               goto out_ro;
+
+       spin_lock(&ubi->volumes_lock);
+       ubi->beb_rsvd_pebs -= 1;
+       ubi->bad_peb_count += 1;
+       ubi->good_peb_count -= 1;
+       ubi_calculate_reserved(ubi);
+       if (ubi->beb_rsvd_pebs == 0)
+               ubi_warn("last PEB from the reserved pool was used");
+       spin_unlock(&ubi->volumes_lock);
+
+       return err;
 
+out_ro:
+       ubi_ro_mode(ubi);
        return err;
 }