dm raid: fix discard limits for raid1

commit cc07d72bf350b77faeffee1c37bc52197171473f upstream.

Block core warned that discard_granularity was 0 for dm-raid with
personality of raid1.  Reason is that raid_io_hints() was incorrectly
special-casing raid1 rather than raid0.

Fix raid_io_hints() by removing discard limits settings for
raid1. Check for raid0 instead.

Fixes: 61697a6abd24a ("dm: eliminate 'split_discard_bios' flag from DM target interface")
Cc: stable@vger.kernel.org
Reported-by: Zdenek Kabelac <zkabelac@redhat.com>
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Reported-by: Stephan Bärwolf <stephan@matrixstorm.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 56b723d..6dca932 100644 (file)
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -3730,10 +3730,10 @@ static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
        blk_limits_io_opt(limits, chunk_size_bytes * mddev_data_stripes(rs));
 
        /*
-        * RAID1 and RAID10 personalities require bio splitting,
-        * RAID0/4/5/6 don't and process large discard bios properly.
+        * RAID0 and RAID10 personalities require bio splitting,
+        * RAID1/4/5/6 don't and process large discard bios properly.
         */
-       if (rs_is_raid1(rs) || rs_is_raid10(rs)) {
+       if (rs_is_raid0(rs) || rs_is_raid10(rs)) {
                limits->discard_granularity = chunk_size_bytes;
                limits->max_discard_sectors = rs->md.chunk_sectors;
        }