From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55203) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VPa9Y-00077Y-LU for qemu-devel@nongnu.org; Fri, 27 Sep 2013 11:40:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VPa9R-0007sN-MV for qemu-devel@nongnu.org; Fri, 27 Sep 2013 11:40:24 -0400 Received: from mx1.redhat.com ([209.132.183.28]:13384) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VPa9R-0007sC-D5 for qemu-devel@nongnu.org; Fri, 27 Sep 2013 11:40:17 -0400 From: Kevin Wolf Date: Fri, 27 Sep 2013 17:39:27 +0200 Message-Id: <1380296370-14523-28-git-send-email-kwolf@redhat.com> In-Reply-To: <1380296370-14523-1-git-send-email-kwolf@redhat.com> References: <1380296370-14523-1-git-send-email-kwolf@redhat.com> Subject: [Qemu-devel] [PULL 27/30] qcow2: Free only newly allocated clusters on error List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: anthony@codemonkey.ws Cc: kwolf@redhat.com, qemu-devel@nongnu.org From: Max Reitz In expand_zero_clusters_in_l1, a new cluster is only allocated if it was not already preallocated. On error, such preallocated clusters should not be freed, but only the newly allocated ones. Signed-off-by: Max Reitz Signed-off-by: Kevin Wolf --- block/qcow2-cluster.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index c743db1..91d07f2 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -1554,6 +1554,7 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table, uint64_t l2_entry = be64_to_cpu(l2_table[j]); int64_t offset = l2_entry & L2E_OFFSET_MASK, cluster_index; int cluster_type = qcow2_get_cluster_type(l2_entry); + bool preallocated = offset != 0; if (cluster_type == QCOW2_CLUSTER_NORMAL) { cluster_index = offset >> s->cluster_bits; @@ -1579,8 +1580,7 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table, continue; } - if (!offset) { - /* not preallocated */ + if (!preallocated) { if (!bs->backing_hd) { /* not backed; therefore we can simply deallocate the * cluster */ @@ -1599,16 +1599,20 @@ static int expand_zero_clusters_in_l1(BlockDriverState *bs, uint64_t *l1_table, ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT, offset, s->cluster_size); if (ret < 0) { - qcow2_free_clusters(bs, offset, s->cluster_size, - QCOW2_DISCARD_ALWAYS); + if (!preallocated) { + qcow2_free_clusters(bs, offset, s->cluster_size, + QCOW2_DISCARD_ALWAYS); + } goto fail; } ret = bdrv_write_zeroes(bs->file, offset / BDRV_SECTOR_SIZE, s->cluster_sectors); if (ret < 0) { - qcow2_free_clusters(bs, offset, s->cluster_size, - QCOW2_DISCARD_ALWAYS); + if (!preallocated) { + qcow2_free_clusters(bs, offset, s->cluster_size, + QCOW2_DISCARD_ALWAYS); + } goto fail; } -- 1.8.1.4