From: Joe Thornber <ejt@redhat.com>

The thin provisioning target commits internal metadata on flush.  So it
should receive flushes regardless of whether the underlying devices
support them.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

---
 drivers/md/dm-thin.c |    1 +
 1 file changed, 1 insertion(+)

Index: linux-3.5/drivers/md/dm-thin.c
===================================================================
--- linux-3.5.orig/drivers/md/dm-thin.c
+++ linux-3.5/drivers/md/dm-thin.c
@@ -2652,6 +2652,7 @@ static int thin_ctr(struct dm_target *ti
 		goto bad_thin_open;
 
 	ti->num_flush_requests = 1;
+	ti->flush_supported = true;
 
 	/* In case the pool supports discards, pass them on. */
 	if (tc->pool->pf.discard_enabled) {