Signed-off-by: Max Reitz <mre...@redhat.com> --- tests/qemu-iotests/244 | 65 ++++++++++++++++++++++++++++++++++++++ tests/qemu-iotests/244.out | 23 ++++++++++++++ 2 files changed, 88 insertions(+)
diff --git a/tests/qemu-iotests/244 b/tests/qemu-iotests/244 index efe3c0428b..c2fdeab0c7 100755 --- a/tests/qemu-iotests/244 +++ b/tests/qemu-iotests/244 @@ -217,6 +217,71 @@ $QEMU_IMG amend -f $IMGFMT -o "data_file=blkdebug::$TEST_IMG.data" "$TEST_IMG" $QEMU_IMG convert -f $IMGFMT -O $IMGFMT -n -C "$TEST_IMG.src" "$TEST_IMG" $QEMU_IMG compare -f $IMGFMT -F $IMGFMT "$TEST_IMG.src" "$TEST_IMG" +echo +echo '=== Preallocation with data-file-raw ===' + +echo +echo '--- Using a non-zeroed data file ---' + +# Using data-file-raw must enforce at least metadata preallocation so +# that it does not matter whether one reads the raw file or the qcow2 +# file + +# The real test we would like to do here is to use an existing block +# device with some random data on it as the external data file. +# When creating the qcow2 file, it would not be overwritten and its +# data would stay as it is. However, using an existing block device +# is a bit cumbersome in a test, so we are going to cheat by using a +# normal regular file. + +# Unfortunately, this will O_CREAT | O_TRUNC that regular file, so +# there is no point in creating it beforehand and filling it with +# random data: +_make_test_img -o "data_file=$TEST_IMG.data,data_file_raw=on" 1M + +# So now comes the cheating: We write directly into the data file. +# That is actually unsupported, but it works for this test. +# (As written above, the actual case would be to use a block device +# as the external data file. Such a device would not be emptied when +# the qcow2 file is created, so its data would persist that step.) +$QEMU_IO -f raw -c 'write -P 42 0 1M' "$TEST_IMG.data" | _filter_qemu_io + +echo +echo 'Comparing pattern:' + +# Reading from either the qcow2 file or the data file should return +# the same result: +$QEMU_IO -f raw -c 'read -P 42 0 1M' "$TEST_IMG.data" | _filter_qemu_io +$QEMU_IO -f $IMGFMT -c 'read -P 42 0 1M' "$TEST_IMG" | _filter_qemu_io + +# For good measure +$QEMU_IMG compare -f raw "$TEST_IMG.data" "$TEST_IMG" + +echo +echo '--- Giving a backing file at runtime ---' + +# qcow2 files with data-file-raw cannot have backing files given by +# their image header, but qemu will allow you to set a backing node at +# runtime -- it should not have any effect, though (because reading +# from the qcow2 node should return the same data as reading from the +# raw node). + +_make_test_img -o "data_file=$TEST_IMG.data,data_file_raw=on" 1M +TEST_IMG="$TEST_IMG.base" _make_test_img 1M + +# Write something that is not zero into the base image +$QEMU_IO -c 'write -P 42 0 1M' "$TEST_IMG.base" | _filter_qemu_io + +echo +echo 'Comparing qcow2 image and raw data file:' + +# $TEST_IMG and $TEST_IMG.data must show the same data at all times; +# that is, the qcow2 node must not fall through to the backing image +# at any point +$QEMU_IMG compare --image-opts \ + "driver=raw,file.filename=$TEST_IMG.data" \ + "file.filename=$TEST_IMG,backing.file.filename=$TEST_IMG.base" + # success, all done echo "*** done" rm -f $seq.full diff --git a/tests/qemu-iotests/244.out b/tests/qemu-iotests/244.out index 24f02363dd..34d6b0e626 100644 --- a/tests/qemu-iotests/244.out +++ b/tests/qemu-iotests/244.out @@ -130,4 +130,27 @@ Offset Length Mapped to File Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 data_file=TEST_DIR/t.IMGFMT.data Images are identical. Images are identical. + +=== Preallocation with data-file-raw === + +--- Using a non-zeroed data file --- +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 data_file=TEST_DIR/t.IMGFMT.data data_file_raw=on +wrote 1048576/1048576 bytes at offset 0 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) + +Comparing pattern: +read 1048576/1048576 bytes at offset 0 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +read 1048576/1048576 bytes at offset 0 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +Images are identical. + +--- Giving a backing file at runtime --- +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 data_file=TEST_DIR/t.IMGFMT.data data_file_raw=on +Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=1048576 +wrote 1048576/1048576 bytes at offset 0 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) + +Comparing qcow2 image and raw data file: +Images are identical. *** done -- 2.26.2
