From 2d97fde43991829f74e1e258bb82031605bf9bca Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Wed, 29 Apr 2020 16:11:26 +0200 Subject: [PATCH] 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 +++++++++------- qemu-img.c | 19 ++++++++++++++----- tests/qemu-iotests/098.out | 8 ++++---- 3 files changed, 27 insertions(+), 16 deletions(-) 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. diff --git a/qemu-img.c b/qemu-img.c index 6a4327aaba..f1795c788c 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -1104,11 +1104,20 @@ static int img_commit(int argc, char **argv) goto unref_backing; } - if (!drop && bs->drv->bdrv_make_empty) { - ret = bs->drv->bdrv_make_empty(bs); - if (ret) { - error_setg_errno(&local_err, -ret, "Could not empty %s", - filename); + if (!drop) { + BlockBackend *old_backing_blk; + + old_backing_blk = blk_new_with_bs(bs, BLK_PERM_WRITE, BLK_PERM_ALL, + &local_err); + if (!old_backing_blk) { + goto unref_backing; + } + ret = blk_make_empty(old_backing_blk, &local_err); + blk_unref(old_backing_blk); + if (ret == -ENOTSUP) { + error_free(local_err); + local_err = NULL; + } else if (ret < 0) { goto unref_backing; } } diff --git a/tests/qemu-iotests/098.out b/tests/qemu-iotests/098.out index 7634d0e8b0..23cf371f53 100644 --- a/tests/qemu-iotests/098.out +++ b/tests/qemu-iotests/098.out @@ -6,7 +6,7 @@ Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=67108864 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 backing_file=TEST_DIR/t.IMGFMT.base wrote 65536/65536 bytes at offset 0 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) -qemu-img: Could not empty blkdebug:TEST_DIR/blkdebug.conf:TEST_DIR/t.IMGFMT: Input/output error +qemu-img: Failed to empty blkdebug:TEST_DIR/blkdebug.conf:TEST_DIR/t.IMGFMT: Input/output error No errors were found on the image. === empty_image_prepare === @@ -15,7 +15,7 @@ Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=67108864 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 backing_file=TEST_DIR/t.IMGFMT.base wrote 65536/65536 bytes at offset 0 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) -qemu-img: Could not empty blkdebug:TEST_DIR/blkdebug.conf:TEST_DIR/t.IMGFMT: Input/output error +qemu-img: Failed to empty blkdebug:TEST_DIR/blkdebug.conf:TEST_DIR/t.IMGFMT: Input/output error Leaked cluster 4 refcount=1 reference=0 Leaked cluster 5 refcount=1 reference=0 Repairing cluster 4 refcount=1 reference=0 @@ -28,7 +28,7 @@ Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=67108864 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 backing_file=TEST_DIR/t.IMGFMT.base wrote 65536/65536 bytes at offset 0 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) -qemu-img: Could not empty blkdebug:TEST_DIR/blkdebug.conf:TEST_DIR/t.IMGFMT: Input/output error +qemu-img: Failed to empty blkdebug:TEST_DIR/blkdebug.conf:TEST_DIR/t.IMGFMT: Input/output error ERROR cluster 0 refcount=0 reference=1 ERROR cluster 1 refcount=0 reference=1 ERROR cluster 3 refcount=0 reference=1 @@ -42,7 +42,7 @@ Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=67108864 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 backing_file=TEST_DIR/t.IMGFMT.base wrote 65536/65536 bytes at offset 0 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) -qemu-img: Could not empty blkdebug:TEST_DIR/blkdebug.conf:TEST_DIR/t.IMGFMT: Input/output error +qemu-img: Failed to empty blkdebug:TEST_DIR/blkdebug.conf:TEST_DIR/t.IMGFMT: Input/output error ERROR cluster 0 refcount=0 reference=1 ERROR cluster 1 refcount=0 reference=1 ERROR cluster 3 refcount=0 reference=1