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 <mreitz@redhat.com>
Message-Id: <20200429141126.85159-5-mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[kwolf: Fixed up reference output for 098]
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Max Reitz 2020-04-29 16:11:26 +02:00 committed by Kevin Wolf
parent 2b7bbdbdef
commit 2d97fde439
3 changed files with 27 additions and 16 deletions

View File

@ -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.

View File

@ -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;
}
}

View File

@ -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