diff mbox

[3.11,38/93] dm cache: always split discards on cache block boundaries

Message ID 1403528592-2163-39-git-send-email-luis.henriques@canonical.com
State New
Headers show

Commit Message

Luis Henriques June 23, 2014, 1:02 p.m. UTC 
3.11.10.12 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Heinz Mauelshagen <heinzm@redhat.com>

commit f1daa838e861ae1a0fb7cd9721a21258430fcc8c upstream.

The DM cache target cannot cope with discards that span multiple cache
blocks, so each discard bio that spans more than one cache block must
get split by the DM core.

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
---
 drivers/md/dm-cache-target.c | 2 ++
 1 file changed, 2 insertions(+)
diff mbox

Patch

diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c
index 8175041200c7..cb51c1d05417 100644
--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -1929,6 +1929,8 @@  static int cache_create(struct cache_args *ca, struct cache **result)
 	ti->num_discard_bios = 1;
 	ti->discards_supported = true;
 	ti->discard_zeroes_data_unsupported = true;
+	/* Discard bios must be split on a block boundary */
+	ti->split_discard_bios = true;
 
 	cache->features = ca->features;
 	ti->per_bio_data_size = get_per_bio_data_size(cache);