This was deprecated back in bc5ee6da7 (qcow2: Deprecate use of qemu-img amend to change backing file), and no one in the meantime has given any reasons why it should be supported. Time to make change attempts a hard error (but for convenience, specifying the _same_ backing chain is not forbidden). Update a couple of iotests to match. Signed-off-by: Eric Blake <eblake(a)redhat.com&gt; --- docs/system/deprecated.rst | 12 ------------ docs/system/removed-features.rst | 12 ++++++++++++ block/qcow2.c | 13 ++++--------- tests/qemu-iotests/061 | 3 +++ tests/qemu-iotests/061.out | 3 ++- tests/qemu-iotests/082.out | 6 ++++-- 6 files changed, 25 insertions(+), 24 deletions(-) diff --git a/docs/system/deprecated.rst b/docs/system/deprecated.rst index 80cae862528a..9ec1a9d0e03e 100644 --- a/docs/system/deprecated.rst +++ b/docs/system/deprecated.rst @@ -315,18 +315,6 @@ this CPU is also deprecated. Related binaries ---------------- -qemu-img amend to adjust backing file (since 5.1) -''''''''''''''''''''''''''''''''''''''''''''''''' - -The use of ``qemu-img amend`` to modify the name or format of a qcow2 -backing image is deprecated; this functionality was never fully -documented or tested, and interferes with other amend operations that -need access to the original backing image (such as deciding whether a -v3 zero cluster may be left unallocated when converting to a v2 -image). Rather, any changes to the backing chain should be performed -with ``qemu-img rebase -u`` either before or after the remaining -changes being performed by amend, as appropriate. - qemu-img backing file without format (since 5.1) '''''''''''''''''''''''''''''''''''''''''''''''' diff --git a/docs/system/removed-features.rst b/docs/system/removed-features.rst index 29e90601a51a..28b5df757d35 100644 --- a/docs/system/removed-features.rst +++ b/docs/system/removed-features.rst @@ -454,6 +454,18 @@ topologies described with -smp include all possible cpus, i.e. The ``enforce-config-section`` property was replaced by the ``-global migration.send-configuration={on|off}`` option. +qemu-img amend to adjust backing file (removed in 6.1) +'''''''''''''''''''''''''''''''''''''''''''''''''''''' + +The use of ``qemu-img amend`` to modify the name or format of a qcow2 +backing image was never fully documented or tested, and interferes +with other amend operations that need access to the original backing +image (such as deciding whether a v3 zero cluster may be left +unallocated when converting to a v2 image). Any changes to the +backing chain should be performed with ``qemu-img rebase -u`` either +before or after the remaining changes being performed by amend, as +appropriate. + Block devices ------------- diff --git a/block/qcow2.c b/block/qcow2.c index 9727ae8fe341..898c4fc4464c 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -5620,15 +5620,10 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, if (backing_file || backing_format) { if (g_strcmp0(backing_file, s->image_backing_file) || g_strcmp0(backing_format, s->image_backing_format)) { - warn_report("Deprecated use of amend to alter the backing file; " - "use qemu-img rebase instead"); - } - ret = qcow2_change_backing_file(bs, - backing_file ?: s->image_backing_file, - backing_format ?: s->image_backing_format); - if (ret < 0) { - error_setg_errno(errp, -ret, "Failed to change the backing file"); - return ret; + error_setg(errp, "Cannot amend the backing file"); + error_append_hint(errp, + "You can use 'qemu-img rebase' instead.\n"); + return -EINVAL; } } diff --git a/tests/qemu-iotests/061 b/tests/qemu-iotests/061 index e26d94a0df31..9507c223bda4 100755 --- a/tests/qemu-iotests/061 +++ b/tests/qemu-iotests/061 @@ -167,6 +167,9 @@ _make_test_img -o "compat=1.1" 64M TEST_IMG="$TEST_IMG.base" _make_test_img -o "compat=1.1" 64M $QEMU_IO -c "write -P 0x2a 0 128k" "$TEST_IMG.base" | _filter_qemu_io $QEMU_IO -c "read -P 0 0 128k" "$TEST_IMG" | _filter_qemu_io +$QEMU_IMG amend -o "backing_file=$TEST_IMG.base,backing_fmt=qcow2" \ + "$TEST_IMG" && echo "unexpected pass" +$QEMU_IMG rebase -u -b "$TEST_IMG.base" -F qcow2 "$TEST_IMG" $QEMU_IMG amend -o "backing_file=$TEST_IMG.base,backing_fmt=qcow2" "$TEST_IMG" $QEMU_IO -c "read -P 0x2a 0 128k" "$TEST_IMG" | _filter_qemu_io _check_test_img diff --git a/tests/qemu-iotests/061.out b/tests/qemu-iotests/061.out index ee30da266514..7ecbd4dea875 100644 --- a/tests/qemu-iotests/061.out +++ b/tests/qemu-iotests/061.out @@ -370,7 +370,8 @@ wrote 131072/131072 bytes at offset 0 128 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) read 131072/131072 bytes at offset 0 128 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) -qemu-img: warning: Deprecated use of amend to alter the backing file; use qemu-img rebase instead +qemu-img: Cannot amend the backing file +You can use 'qemu-img rebase' instead. read 131072/131072 bytes at offset 0 128 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) No errors were found on the image. diff --git a/tests/qemu-iotests/082.out b/tests/qemu-iotests/082.out index b70c12c1393d..077ed0f2c7d9 100644 --- a/tests/qemu-iotests/082.out +++ b/tests/qemu-iotests/082.out @@ -808,12 +808,14 @@ Amend options for 'qcow2': size=<size> - Virtual disk size Testing: amend -f qcow2 -o backing_file=TEST_DIR/t.qcow2,,help TEST_DIR/t.qcow2 -qemu-img: warning: Deprecated use of amend to alter the backing file; use qemu-img rebase instead +qemu-img: Cannot amend the backing file +You can use 'qemu-img rebase' instead. Testing: rebase -u -b -f qcow2 TEST_DIR/t.qcow2 Testing: amend -f qcow2 -o backing_file=TEST_DIR/t.qcow2,,? TEST_DIR/t.qcow2 -qemu-img: warning: Deprecated use of amend to alter the backing file; use qemu-img rebase instead +qemu-img: Cannot amend the backing file +You can use 'qemu-img rebase' instead. Testing: rebase -u -b -f qcow2 TEST_DIR/t.qcow2 -- 2.31.1