iotests/308: Add test for 'write -zu'

Try writing zeroes to a FUSE export while allowing the area to be
unmapped; block/file-posix.c generally implements writing zeroes with
BDRV_REQ_MAY_UNMAP ('write -zu') by calling fallocate(PUNCH_HOLE).  This
used to lead to a blk_pdiscard() in the FUSE export, which may or may
not lead to the area being zeroed.  HEAD^ fixed this to use
blk_pwrite_zeroes() instead (again with BDRV_REQ_MAY_UNMAP), so verify
that running `qemu-io 'write -zu'` on a FUSE exports always results in
zeroes being written.

Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20230227104725.33511-3-hreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Hanna Czenczek 2023-02-27 11:47:25 +01:00 committed by Kevin Wolf
parent 1703eb1c27
commit 27e0d8b508
2 changed files with 78 additions and 0 deletions

View File

@ -370,6 +370,49 @@ echo
echo '=== Compare copy with original ==='
$QEMU_IMG compare -f raw -F $IMGFMT "$COPIED_IMG" "$TEST_IMG"
_cleanup_test_img
echo
echo '=== Writing zeroes while unmapping ==='
# Regression test for https://gitlab.com/qemu-project/qemu/-/issues/1507
_make_test_img 64M
$QEMU_IO -c 'write -s /dev/urandom 0 64M' "$TEST_IMG" | _filter_qemu_io
_launch_qemu
_send_qemu_cmd $QEMU_HANDLE \
"{'execute': 'qmp_capabilities'}" \
'return'
_send_qemu_cmd $QEMU_HANDLE \
"{'execute': 'blockdev-add',
'arguments': {
'driver': '$IMGFMT',
'node-name': 'node-format',
'file': {
'driver': 'file',
'filename': '$TEST_IMG'
}
} }" \
'return'
fuse_export_add 'export' "'mountpoint': '$EXT_MP', 'writable': true"
# Try writing zeroes by unmapping
$QEMU_IO -f raw -c 'write -zu 0 64M' "$EXT_MP" | _filter_qemu_io
# Check the result
$QEMU_IO -f raw -c 'read -P 0 0 64M' "$EXT_MP" | _filter_qemu_io
_send_qemu_cmd $QEMU_HANDLE \
"{'execute': 'quit'}" \
'return'
wait=yes _cleanup_qemu
# Check the original image
$QEMU_IO -c 'read -P 0 0 64M' "$TEST_IMG" | _filter_qemu_io
_cleanup_test_img
# success, all done
echo "*** done"

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@ -171,4 +171,39 @@ OK: Post-truncate image size is as expected
=== Compare copy with original ===
Images are identical.
=== Writing zeroes while unmapping ===
Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
wrote 67108864/67108864 bytes at offset 0
64 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
{'execute': 'qmp_capabilities'}
{"return": {}}
{'execute': 'blockdev-add',
'arguments': {
'driver': 'IMGFMT',
'node-name': 'node-format',
'file': {
'driver': 'file',
'filename': 'TEST_DIR/t.IMGFMT'
}
} }
{"return": {}}
{'execute': 'block-export-add',
'arguments': {
'type': 'fuse',
'id': 'export',
'node-name': 'node-format',
'mountpoint': 'TEST_DIR/t.IMGFMT.fuse', 'writable': true
} }
{"return": {}}
wrote 67108864/67108864 bytes at offset 0
64 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
read 67108864/67108864 bytes at offset 0
64 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
{'execute': 'quit'}
{"return": {}}
{"timestamp": {"seconds": TIMESTAMP, "microseconds": TIMESTAMP}, "event": "SHUTDOWN", "data": {"guest": false, "reason": "host-qmp-quit"}}
{"timestamp": {"seconds": TIMESTAMP, "microseconds": TIMESTAMP}, "event": "BLOCK_EXPORT_DELETED", "data": {"id": "export"}}
read 67108864/67108864 bytes at offset 0
64 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
*** done