-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Milan Broz <mbroz@redhat.com>

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>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
Gitweb:     http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=9c89f8be1a7d14aad9d2c3f7d90d7d88f82c61e2

 drivers/md/dm-crypt.c |    3 +++
 1 file changed, 3 insertions(+)

--- linux-2.6.21.6.orig/drivers/md/dm-crypt.c
+++ linux-2.6.21.6/drivers/md/dm-crypt.c
@@ -954,6 +954,9 @@ static int crypt_map(struct dm_target *t
 	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;

--