Merge tag 'dm-3.10-changes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm

Pull device-mapper updates from Alasdair Kergon:
 "Allow devices that hold metadata for the device-mapper thin
  provisioning target to be extended easily; allow WRITE SAME on
  multipath devices; an assortment of little fixes and clean-ups."

* tag 'dm-3.10-changes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm: (21 commits)
  dm cache: set config value
  dm cache: move config fns
  dm thin: generate event when metadata threshold passed
  dm persistent metadata: add space map threshold callback
  dm persistent data: add threshold callback to space map
  dm thin: detect metadata device resizing
  dm persistent data: support space map resizing
  dm thin: open dev read only when possible
  dm thin: refactor data dev resize
  dm cache: replace memcpy with struct assignment
  dm cache: fix typos in comments
  dm cache policy: fix description of lookup fn
  dm: document iterate_devices
  dm persistent data: fix error message typos
  dm cache: tune migration throttling
  dm mpath: enable WRITE SAME support
  dm table: fix write same support
  dm bufio: avoid a possible __vmalloc deadlock
  dm snapshot: fix error return code in snapshot_ctr
  dm cache: fix error return code in cache_create
  ...

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/md/dm-cache-policy.h b/drivers/md/dm-cache-policy.h
index 558bdfdabf5..33369ca9614 100644
--- a/drivers/md/dm-cache-policy.h
+++ b/drivers/md/dm-cache-policy.h
@@ -130,8 +130,8 @@ struct dm_cache_policy {
 	 *
 	 * Must not block.
 	 *
-	 * Returns 1 iff in cache, 0 iff not, < 0 on error (-EWOULDBLOCK
-	 * would be typical).
+	 * Returns 0 if in cache, -ENOENT if not, < 0 for other errors
+	 * (-EWOULDBLOCK would be typical).
 	 */
 	int (*lookup)(struct dm_cache_policy *p, dm_oblock_t oblock, dm_cblock_t *cblock);