tests: extend test 131 to cover availability of the discard operation

This patch contains test which minimally tests discard and new cluster
allocation logic.

The following checks are added:
* write 2 clusters, discard the first allocated
* write another cluster, check that the hole is filled
* write 2 clusters, discard the first allocated, write 1 cluster at
  non-aligned to cluster offset (2 new clusters should be allocated)

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>

tests/qemu-iotests/131

@@ -74,6 +74,37 @@ poke_file "$TEST_IMG" "$inuse_offset" "\x59\x6e\x6f\x74"
 echo "== read corrupted image with repairing =="
 { $QEMU_IO -c "read -P 0x11 $CLUSTER_SIZE $CLUSTER_SIZE" "$TEST_IMG"; } 2>&1 | _filter_qemu_io | _filter_testdir
 
+echo "== check discard =="
+
+# Clear image
+_make_test_img $size
+
+{ $QEMU_IO -c "write -P 0x11 0 $CLUSTER_DBL_SIZE" "$TEST_IMG"; } 2>&1 | _filter_qemu_io | _filter_testdir
+{ $QEMU_IMG map "$TEST_IMG"; } 2>&1 | _filter_qemu_img_map
+{ $QEMU_IO -c "discard 0 $CLUSTER_SIZE" "$TEST_IMG"; } 2>&1 | _filter_qemu_io | _filter_testdir
+{ $QEMU_IMG map "$TEST_IMG"; } 2>&1 | _filter_qemu_img_map
+{ $QEMU_IO -c "read -P 0 0 $CLUSTER_SIZE" "$TEST_IMG"; } 2>&1 | _filter_qemu_io | _filter_testdir
+
+echo "== check simple allocation over the discarded hole =="
+
+{ $QEMU_IO -c "write -P 0x11 $CLUSTER_DBL_SIZE $CLUSTER_SIZE" "$TEST_IMG"; } 2>&1 | _filter_qemu_io | _filter_testdir
+{ $QEMU_IMG map "$TEST_IMG"; } 2>&1 | _filter_qemu_img_map
+{ $QEMU_IO -c "read -P 0x11 $CLUSTER_DBL_SIZE $CLUSTER_SIZE" "$TEST_IMG"; } 2>&1 | _filter_qemu_io | _filter_testdir
+
+echo "== check more complex allocation over the discard hole =="
+
+# Clear image
+_make_test_img $size
+
+{ $QEMU_IO -c "write -P 0x11 $CLUSTER_DBL_SIZE $CLUSTER_DBL_SIZE" "$TEST_IMG"; } 2>&1 | _filter_qemu_io | _filter_testdir
+{ $QEMU_IO -c "discard $CLUSTER_DBL_SIZE $CLUSTER_SIZE" "$TEST_IMG"; } 2>&1 | _filter_qemu_io | _filter_testdir
+# There is 1 cluster hole. Fill it fully and allocate 1 cluster at the end
+{ $QEMU_IO -c "write -P 0x12 $CLUSTER_HALF_SIZE $CLUSTER_SIZE" "$TEST_IMG"; } 2>&1 | _filter_qemu_io | _filter_testdir
+{ $QEMU_IMG map "$TEST_IMG"; } 2>&1 | _filter_qemu_img_map
+{ $QEMU_IO -c "read -P 0x12 $CLUSTER_HALF_SIZE $CLUSTER_SIZE" "$TEST_IMG"; } 2>&1 | _filter_qemu_io | _filter_testdir
+{ $QEMU_IO -c "read -P 0 0 $CLUSTER_HALF_SIZE" "$TEST_IMG"; } 2>&1 | _filter_qemu_io | _filter_testdir
+{ $QEMU_IO -c "read -P 0 $((CLUSTER_SIZE + CLUSTER_HALF_SIZE)) $CLUSTER_HALF_SIZE" "$TEST_IMG"; } 2>&1 | _filter_qemu_io | _filter_testdir
+
 echo "== allocate with backing =="
 # Verify that allocating clusters works fine even when there is a backing image.
 # Regression test for a bug where we would pass a buffer read from the backing

tests/qemu-iotests/131.out

@@ -26,6 +26,44 @@ read 524288/524288 bytes at offset 0
 Repairing image was not closed correctly
 read 1048576/1048576 bytes at offset 1048576
 1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+== check discard ==
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
+wrote 2097152/2097152 bytes at offset 0
+2 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+Offset          Length          File
+0               0x200000        TEST_DIR/t.IMGFMT
+discard 1048576/1048576 bytes at offset 0
+1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+Offset          Length          File
+0x100000        0x100000        TEST_DIR/t.IMGFMT
+read 1048576/1048576 bytes at offset 0
+1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+== check simple allocation over the discarded hole ==
+wrote 1048576/1048576 bytes at offset 2097152
+1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+Offset          Length          File
+0x100000        0x100000        TEST_DIR/t.IMGFMT
+0x200000        0x100000        TEST_DIR/t.IMGFMT
+read 1048576/1048576 bytes at offset 2097152
+1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+== check more complex allocation over the discard hole ==
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
+wrote 2097152/2097152 bytes at offset 2097152
+2 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+discard 1048576/1048576 bytes at offset 2097152
+1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 1048576/1048576 bytes at offset 524288
+1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+Offset          Length          File
+0               0x100000        TEST_DIR/t.IMGFMT
+0x100000        0x100000        TEST_DIR/t.IMGFMT
+0x300000        0x100000        TEST_DIR/t.IMGFMT
+read 1048576/1048576 bytes at offset 524288
+1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 524288/524288 bytes at offset 0
+512 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 524288/524288 bytes at offset 1572864
+512 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 == allocate with backing ==
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
 Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=67108864