qemu-iotests: Test one more spot for optimizing write_zeroes

Add another test to 154, showing that we currently allocate a
data cluster in the top layer if any sector of the backing file
was allocated.  The next patch will optimize this case.
Signed-off-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

tests/qemu-iotests/154

@@ -114,6 +114,46 @@ $QEMU_IO -c "read -P 0 40k 3k" "$TEST_IMG" | _filter_qemu_io
 
 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 
+echo
+echo == write_zeroes covers non-zero data ==
+
+CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
+_make_test_img -b "$TEST_IMG.base"
+
+# non-zero data at front of request
+# Backing file: -- XX -- --
+# Active layer: -- 00 00 --
+
+$QEMU_IO -c "write -P 0x11 5k 1k" "$TEST_IMG.base" | _filter_qemu_io
+$QEMU_IO -c "write -z 5k 2k" "$TEST_IMG" | _filter_qemu_io
+$QEMU_IO -c "read -P 0 4k 4k" "$TEST_IMG" | _filter_qemu_io
+
+# non-zero data at end of request
+# Backing file: -- -- XX --
+# Active layer: -- 00 00 --
+
+$QEMU_IO -c "write -P 0x11 14k 1k" "$TEST_IMG.base" | _filter_qemu_io
+$QEMU_IO -c "write -z 13k 2k" "$TEST_IMG" | _filter_qemu_io
+$QEMU_IO -c "read -P 0 12k 4k" "$TEST_IMG" | _filter_qemu_io
+
+# non-zero data matches size of request
+# Backing file: -- XX XX --
+# Active layer: -- 00 00 --
+
+$QEMU_IO -c "write -P 0x11 21k 2k" "$TEST_IMG.base" | _filter_qemu_io
+$QEMU_IO -c "write -z 21k 2k" "$TEST_IMG" | _filter_qemu_io
+$QEMU_IO -c "read -P 0 20k 4k" "$TEST_IMG" | _filter_qemu_io
+
+# non-zero data smaller than request
+# Backing file: -- -X X- --
+# Active layer: -- 00 00 --
+
+$QEMU_IO -c "write -P 0x11 30208 1k" "$TEST_IMG.base" | _filter_qemu_io
+$QEMU_IO -c "write -z 29k 2k" "$TEST_IMG" | _filter_qemu_io
+$QEMU_IO -c "read -P 0 28k 4k" "$TEST_IMG" | _filter_qemu_io
+
+$QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
+
 echo
 echo == spanning two clusters, non-zero before request ==
 

tests/qemu-iotests/154.out

@@ -74,6 +74,43 @@ read 3072/3072 bytes at offset 40960
 { "start": 40960, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": 24576},
 { "start": 45056, "length": 134172672, "depth": 1, "zero": true, "data": false}]
 
+== write_zeroes covers non-zero data ==
+Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=134217728
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file=TEST_DIR/t.IMGFMT.base
+wrote 1024/1024 bytes at offset 5120
+1 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 2048/2048 bytes at offset 5120
+2 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 4096/4096 bytes at offset 4096
+4 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 1024/1024 bytes at offset 14336
+1 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 2048/2048 bytes at offset 13312
+2 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 4096/4096 bytes at offset 12288
+4 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 2048/2048 bytes at offset 21504
+2 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 2048/2048 bytes at offset 21504
+2 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 4096/4096 bytes at offset 20480
+4 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 1024/1024 bytes at offset 30208
+1 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 2048/2048 bytes at offset 29696
+2 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 4096/4096 bytes at offset 28672
+4 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+[{ "start": 0, "length": 4096, "depth": 1, "zero": true, "data": false},
+{ "start": 4096, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": 20480},
+{ "start": 8192, "length": 4096, "depth": 1, "zero": true, "data": false},
+{ "start": 12288, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": 24576},
+{ "start": 16384, "length": 4096, "depth": 1, "zero": true, "data": false},
+{ "start": 20480, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": 28672},
+{ "start": 24576, "length": 4096, "depth": 1, "zero": true, "data": false},
+{ "start": 28672, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": 32768},
+{ "start": 32768, "length": 134184960, "depth": 1, "zero": true, "data": false}]
+
 == spanning two clusters, non-zero before request ==
 Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=134217728
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file=TEST_DIR/t.IMGFMT.base