diff mbox

[PULL,11/20] block: fix race in bdrv_co_discard with drive-mirror

Message ID 1466431531-17806-12-git-send-email-stefanha@redhat.com
State New
Headers show

Commit Message

Stefan Hajnoczi June 20, 2016, 2:05 p.m. UTC 
From: "Denis V. Lunev" <den@openvz.org>

Actually we must set dirty bitmap dirty after we have written all our
zeroes for correct processing in drive mirror code. In the other case
we can face not zeroes in this area in mirror_iteration.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy<vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1466093381-6120-3-git-send-email-den@openvz.org
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/io.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff mbox

Patch

diff --git a/block/io.c b/block/io.c
index 3527d91..8ab6f95 100644
--- a/block/io.c
+++ b/block/io.c
@@ -2349,7 +2349,6 @@  int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num,
 
     tracked_request_begin(&req, bs, sector_num << BDRV_SECTOR_BITS,
                           nb_sectors << BDRV_SECTOR_BITS, BDRV_TRACKED_DISCARD);
-    bdrv_set_dirty(bs, sector_num, nb_sectors);
 
     max_discard = MIN_NON_ZERO(bs->bl.max_discard, BDRV_REQUEST_MAX_SECTORS);
     while (nb_sectors > 0) {
@@ -2398,6 +2397,8 @@  int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num,
     }
     ret = 0;
 out:
+    bdrv_set_dirty(bs, req.offset >> BDRV_SECTOR_BITS,
+                   req.bytes >> BDRV_SECTOR_BITS);
     tracked_request_end(&req);
     return ret;
 }