dm crypt: disable barriers

Disable barriers in dm-crypt because of current workqueue processing can
reorder requests.

This must be addresed later but for now disabling barriers is needed to
prevent data corruption.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index d8121234c347..8527827b24f1 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -954,6 +954,9 @@ static int crypt_map(struct dm_target *ti, struct bio *bio,
         struct crypt_config *cc = ti->private;
         struct crypt_io *io;
 
+        if (bio_barrier(bio))
+                return -EOPNOTSUPP;
+
         io = mempool_alloc(cc->io_pool, GFP_NOIO);
         io->target = ti;
         io->base_bio = bio;