From 5fe38a5246e96640345f39f2a40fcbed0f9c717c Mon Sep 17 00:00:00 2001
From: Mikulas Patocka <mpatocka@redhat.com>
Date: Fri, 20 Jul 2012 14:25:05 +0100
Subject: [PATCH] --- yaml --- r: 312107 b: refs/heads/master c:
 650d2a06b4fe1cc1d218c20e256650f68bf0ca31 h: refs/heads/master i:   312105:
 0969ca61ee3fda55ffb85659418fb63ce29d1ce8   312103:
 de249c94e3a23c401a82d2d595162b3276aa0741 v: v3

---
 [refs]                     | 2 +-
 trunk/drivers/md/dm-thin.c | 6 +++++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index 4ad6830c8a8f..ee066cedcb30 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 751f188dd5ab95b3f2b5f2f467c38aae5a2877eb
+refs/heads/master: 650d2a06b4fe1cc1d218c20e256650f68bf0ca31
diff --git a/trunk/drivers/md/dm-thin.c b/trunk/drivers/md/dm-thin.c
index ce59824fb414..68694da0d21d 100644
--- a/trunk/drivers/md/dm-thin.c
+++ b/trunk/drivers/md/dm-thin.c
@@ -1245,7 +1245,10 @@ static void process_discard(struct thin_c *tc, struct bio *bio)
 
 			cell_release_singleton(cell, bio);
 			cell_release_singleton(cell2, bio);
-			remap_and_issue(tc, bio, lookup_result.block);
+			if ((!lookup_result.shared) && pool->pf.discard_passdown)
+				remap_and_issue(tc, bio, lookup_result.block);
+			else
+				bio_endio(bio, 0);
 		}
 		break;
 
@@ -2628,6 +2631,7 @@ static int thin_ctr(struct dm_target *ti, unsigned argc, char **argv)
 	if (tc->pool->pf.discard_enabled) {
 		ti->discards_supported = 1;
 		ti->num_discard_requests = 1;
+		ti->discard_zeroes_data_unsupported = 1;
 	}
 
 	dm_put(pool_md);