[PATCH hci-8.1 2/2] iotests/290: add 'discard' and 'write -z -u' case with a snapshot #VSTOR-151885

[Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>]

Before the previous commit, issuing 'discard' and 'write -z -u'
operations with discard-no-unref=on option enabled led to data
corruption.  Add a test to cover this case.

Signed-off-by: Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>
---
 tests/qemu-iotests/290     | 16 ++++++++++++++++
 tests/qemu-iotests/290.out |  5 +++++
 2 files changed, 21 insertions(+)

diff --git a/tests/qemu-iotests/290 b/tests/qemu-iotests/290
index 4eb929d15fa..9e711275867 100755
--- a/tests/qemu-iotests/290
+++ b/tests/qemu-iotests/290
@@ -126,6 +126,22 @@ $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 echo "# Output of qemu-img map for the image with kept reference"
 $QEMU_IMG map --output=json "$NOUNREF_IMG" | _filter_qemu_img_map
 
+echo
+echo "### Discard with 'discard-no-unref' on a cluster shared with a snapshot"
+echo
+
+_make_test_img 128k
+$QEMU_IO -c 'write -q -P 0xaa 0 128k' "$TEST_IMG" | _filter_qemu_io
+$QEMU_IMG snapshot -c snap "$TEST_IMG"
+QEMU_IO_OPTIONS=$QEMU_IO_OPTIONS_NO_FMT \
+$QEMU_IO -c 'discard -q 0 64k' -c 'write -q -z -u 64k 64k' --image-opts \
+         "driver=$IMGFMT,file.filename=$TEST_IMG,discard-no-unref=on" \
+         | _filter_qemu_io
+$QEMU_IO -c 'read -q -P 0 0 128k' "$TEST_IMG" | _filter_qemu_io
+$QEMU_IMG snapshot -a snap "$TEST_IMG"
+$QEMU_IO -c 'read -q -P 0xaa 0 128k' "$TEST_IMG" | _filter_qemu_io
+_check_test_img
+
 # success, all done
 echo "*** done"
 rm -f $seq.full
diff --git a/tests/qemu-iotests/290.out b/tests/qemu-iotests/290.out
index f790feae81a..aa5d164fa9f 100644
--- a/tests/qemu-iotests/290.out
+++ b/tests/qemu-iotests/290.out
@@ -86,4 +86,9 @@ Images are identical.
 # Output of qemu-img map for the image with kept reference
 [{ "start": 0, "length": 65536, "depth": 0, "present": true, "zero": false, "data": true, "compressed": false, "offset": OFFSET},
 { "start": 65536, "length": 65536, "depth": 0, "present": true, "zero": true, "data": false, "compressed": false, "offset": OFFSET}]
+
+### Discard with 'discard-no-unref' on a cluster shared with a snapshot
+
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=131072
+No errors were found on the image.
 *** done
-- 
2.47.1