From 2d97fde43991829f74e1e258bb82031605bf9bca Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Wed, 29 Apr 2020 16:11:26 +0200 Subject: block: Use blk_make_empty() after commits bdrv_commit() already has a BlockBackend pointing to the BDS that we want to empty, it just has the wrong permissions. qemu-img commit has no BlockBackend pointing to the old backing file yet, but introducing one is simple. After this commit, bdrv_make_empty() is the only remaining caller of BlockDriver.bdrv_make_empty(). Signed-off-by: Max Reitz Message-Id: <20200429141126.85159-5-mreitz@redhat.com> Reviewed-by: Eric Blake [kwolf: Fixed up reference output for 098] Signed-off-by: Kevin Wolf --- block/commit.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) (limited to 'block/commit.c') diff --git a/block/commit.c b/block/commit.c index 87f6096d90..ba60fb7955 100644 --- a/block/commit.c +++ b/block/commit.c @@ -414,7 +414,9 @@ int bdrv_commit(BlockDriverState *bs) } ctx = bdrv_get_aio_context(bs); - src = blk_new(ctx, BLK_PERM_CONSISTENT_READ, BLK_PERM_ALL); + /* WRITE_UNCHANGED is required for bdrv_make_empty() */ + src = blk_new(ctx, BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED, + BLK_PERM_ALL); backing = blk_new(ctx, BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL); ret = blk_insert_bs(src, bs, &local_err); @@ -492,14 +494,14 @@ int bdrv_commit(BlockDriverState *bs) } } - if (drv->bdrv_make_empty) { - ret = drv->bdrv_make_empty(bs); - if (ret < 0) { - goto ro_cleanup; - } - blk_flush(src); + ret = blk_make_empty(src, NULL); + /* Ignore -ENOTSUP */ + if (ret < 0 && ret != -ENOTSUP) { + goto ro_cleanup; } + blk_flush(src); + /* * Make sure all data we wrote to the backing device is actually * stable on disk. -- cgit v1.2.3-55-g7522