dm mpath: support barriers

Flush support for dm-multipath target.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 92bdcbb..f1cf8f7 100644 (file)
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -835,6 +835,8 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc,
                goto bad;
        }
 
+       ti->num_flush_requests = 1;
+
        return 0;
 
  bad: