From 5e4c728df67c47b719c0a6b66875101160074d9e Mon Sep 17 00:00:00 2001
From: Alasdair G Kergon <agk@redhat.com>
Date: Wed, 1 Feb 2006 03:04:55 -0800
Subject: [PATCH] --- yaml --- r: 19330 b: refs/heads/master c:
 4aac0a63fe8d418a2b74e43708f59380ba379a3b h: refs/heads/master v: v3

---
 [refs]                     | 2 +-
 trunk/drivers/md/dm-snap.c | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 748d28926ffb..0da20c0c8980 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 3eaf840e0b0046f56602c524c7ba58a82f5526c5
+refs/heads/master: 4aac0a63fe8d418a2b74e43708f59380ba379a3b
diff --git a/trunk/drivers/md/dm-snap.c b/trunk/drivers/md/dm-snap.c
index ad9b61f16c5e..f3759dd7828e 100644
--- a/trunk/drivers/md/dm-snap.c
+++ b/trunk/drivers/md/dm-snap.c
@@ -792,6 +792,9 @@ static int snapshot_map(struct dm_target *ti, struct bio *bio,
 	if (!s->valid)
 		return -EIO;
 
+	if (unlikely(bio_barrier(bio)))
+		return -EOPNOTSUPP;
+
 	/*
 	 * Write to snapshot - higher level takes care of RW/RO
 	 * flags so we should only get this if we are
@@ -1058,6 +1061,9 @@ static int origin_map(struct dm_target *ti, struct bio *bio,
 	struct dm_dev *dev = (struct dm_dev *) ti->private;
 	bio->bi_bdev = dev->bdev;
 
+	if (unlikely(bio_barrier(bio)))
+		return -EOPNOTSUPP;
+
 	/* Only tell snapshots if this is a write */
 	return (bio_rw(bio) == WRITE) ? do_origin(dev, bio) : 1;
 }