[PATCH] device-mapper multipath: Barriers not supported
dm multipath will report barriers as not supported with this patch.
Signed-off-by: Lars Marowsky-Bree <lmb@suse.de>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 0c1b852..84cdb70 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -765,6 +765,9 @@
struct mpath_io *mpio;
struct multipath *m = (struct multipath *) ti->private;
+ if (bio_barrier(bio))
+ return -EOPNOTSUPP;
+
mpio = mempool_alloc(m->mpio_pool, GFP_NOIO);
dm_bio_record(&mpio->details, bio);
@@ -988,6 +991,9 @@
if ((error == -EWOULDBLOCK) && bio_rw_ahead(bio))
return error;
+ if (error == -EOPNOTSUPP)
+ return error;
+
spin_lock(&m->lock);
if (!m->nr_valid_paths) {
if (!m->queue_if_no_path || m->suspended) {