@@ -122,6 +122,35 @@ $QEMU_IO -f qcow2 -C -c 'read 0 1024' "$TEST_WRAP" | _filter_qemu_io
$QEMU_IO -f qcow2 -c map "$TEST_WRAP"
_check_test_img
+echo
+echo '=== Copy-on-read with subclusters ==='
+echo
+
+# Create base and top images 64K (1 cluster) each. Make subclusters enabled
+# for the top image
+_make_test_img 64K
+IMGPROTO=file IMGFMT=qcow2 TEST_IMG_FILE="$TEST_WRAP" \
+ _make_test_img --no-opts -o extended_l2=true -F "$IMGFMT" -b "$TEST_IMG" \
+ 64K | _filter_img_create
+
+$QEMU_IO -c "write -P 0xaa 0 64k" "$TEST_IMG" | _filter_qemu_io
+
+# Allocate individual subclusters in the top image, and not the whole cluster
+$QEMU_IO -c "write -P 0xbb 28K 2K" -c "write -P 0xcc 34K 2K" "$TEST_WRAP" \
+ | _filter_qemu_io
+
+# Only 2 subclusters should be allocated in the top image at this point
+$QEMU_IMG map "$TEST_WRAP" | _filter_qemu_img_map
+
+# Actual copy-on-read operation
+$QEMU_IO -C -c "read -P 0xaa 30K 4K" "$TEST_WRAP" | _filter_qemu_io
+
+# And here we should have 4 subclusters allocated right in the middle of the
+# top image. Make sure the whole cluster remains unallocated
+$QEMU_IMG map "$TEST_WRAP" | _filter_qemu_img_map
+
+_check_test_img
+
# success, all done
echo '*** done'
status=0
@@ -31,4 +31,28 @@ read 1024/1024 bytes at offset 0
1 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
1 KiB (0x400) bytes allocated at offset 0 bytes (0x0)
No errors were found on the image.
+
+=== Copy-on-read with subclusters ===
+
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=65536
+Formatting 'TEST_DIR/t.wrap.IMGFMT', fmt=IMGFMT size=65536 backing_file=TEST_DIR/t.IMGFMT backing_fmt=IMGFMT
+wrote 65536/65536 bytes at offset 0
+64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 2048/2048 bytes at offset 28672
+2 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 2048/2048 bytes at offset 34816
+2 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+Offset Length File
+0 0x7000 TEST_DIR/t.IMGFMT
+0x7000 0x800 TEST_DIR/t.wrap.IMGFMT
+0x7800 0x1000 TEST_DIR/t.IMGFMT
+0x8800 0x800 TEST_DIR/t.wrap.IMGFMT
+0x9000 0x7000 TEST_DIR/t.IMGFMT
+read 4096/4096 bytes at offset 30720
+4 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+Offset Length File
+0 0x7000 TEST_DIR/t.IMGFMT
+0x7000 0x2000 TEST_DIR/t.wrap.IMGFMT
+0x9000 0x7000 TEST_DIR/t.IMGFMT
+No errors were found on the image.
*** done