From 4aac0a63fe8d418a2b74e43708f59380ba379a3b Mon Sep 17 00:00:00 2001 From: Alasdair G Kergon Date: Wed, 1 Feb 2006 03:04:55 -0800 Subject: [PATCH] [PATCH] device-mapper snapshot: barriers not supported The snapshot and origin targets are incapable of handling barriers and need to indicate this. Signed-off-by: Alasdair G Kergon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/dm-snap.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c index ad9b61f16c5..f3759dd7828 100644 --- a/drivers/md/dm-snap.c +++ b/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; } -- 2.20.1