From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56486) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bkZcu-0002qE-Nr for qemu-devel@nongnu.org; Thu, 15 Sep 2016 12:35:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bkZcq-0004Lh-23 for qemu-devel@nongnu.org; Thu, 15 Sep 2016 12:35:04 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:45479 helo=relay.sw.ru) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bkZcp-0004Ku-Kk for qemu-devel@nongnu.org; Thu, 15 Sep 2016 12:34:59 -0400 From: "Denis V. Lunev" Date: Thu, 15 Sep 2016 19:34:50 +0300 Message-Id: <1473957290-13382-3-git-send-email-den@openvz.org> In-Reply-To: <1473957290-13382-1-git-send-email-den@openvz.org> References: <1473957290-13382-1-git-send-email-den@openvz.org> Subject: [Qemu-devel] [PATCH v3 2/2] mirror: fix improperly filled copy_bitmap for mirror block job List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org, qemu-devel@nongnu.org Cc: den@openvz.org, Stefan Hajnoczi , Fam Zheng , Kevin Wolf , Max Reitz , Jeff Cody bdrv_is_allocated_above() returns true in the case even for completel zeroed areas as BDRV_BLOCK_ALLOCATED flag is set in both cases. The patch stops using bdrv_is_allocated_above() wrapper and switches to bdrv_get_block_status_above() to distinguish zeroed areas and areas with data to avoid extra IO operations if possible. Signed-off-by: Denis V. Lunev CC: Stefan Hajnoczi CC: Fam Zheng CC: Kevin Wolf CC: Max Reitz CC: Jeff Cody --- block/mirror.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/block/mirror.c b/block/mirror.c index e0b3f41..2710f62 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -548,11 +548,11 @@ static void mirror_throttle(MirrorBlockJob *s) static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s) { - int64_t sector_num, end; + int64_t sector_num, end, alloc_mask; BlockDriverState *base = s->base; BlockDriverState *bs = blk_bs(s->common.blk); BlockDriverState *target_bs = blk_bs(s->target); - int ret, n; + int n; end = s->bdev_length / BDRV_SECTOR_SIZE; @@ -585,11 +585,15 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s) mirror_drain(s); } + alloc_mask = base == NULL ? BDRV_BLOCK_ALLOCATED : BDRV_BLOCK_DATA; + /* First part, loop on the sectors and initialize the dirty bitmap. */ for (sector_num = 0; sector_num < end; ) { /* Just to make sure we are not exceeding int limit. */ int nb_sectors = MIN(INT_MAX >> BDRV_SECTOR_BITS, end - sector_num); + int64_t status; + BlockDriverState *file; mirror_throttle(s); @@ -597,13 +601,14 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s) return 0; } - ret = bdrv_is_allocated_above(bs, base, sector_num, nb_sectors, &n); - if (ret < 0) { - return ret; + status = bdrv_get_block_status_above(bs, base, sector_num, + nb_sectors, &n, &file); + if (status < 0) { + return status; } assert(n > 0); - if (ret == 1) { + if (status & alloc_mask) { bdrv_set_dirty_bitmap(s->dirty_bitmap, sector_num, n); } sector_num += n; -- 2.7.4