No tests were covering write zeroes with unmap. Additionally, I wanted to prove that my patch to optimize write zeroes for compat=0.10 images actually had an impact; for that, run: ./check -qcow2 -o compat=0.10 179
Writing the test to work correctly for both old and new qcow2 images is a bit tricky: 'qemu-img map' works for showing whether a cluster is assigned an offset (in the preallocation sense), but older images have to write literal zeroes where newer images can set the zero flag. Thankfully, 'qemu-io alloc' hides the difference, by instead reporting whether a cluster's content comes from the current layer (regardless of whether it was due to a cluster allocation or a flag). Signed-off-by: Eric Blake <ebl...@redhat.com> --- tests/qemu-iotests/179 | 78 ++++++++++++++++++++++++++++++++++++++++++++++ tests/qemu-iotests/179.out | 22 +++++++++++++ tests/qemu-iotests/group | 1 + 3 files changed, 101 insertions(+) create mode 100755 tests/qemu-iotests/179 create mode 100644 tests/qemu-iotests/179.out diff --git a/tests/qemu-iotests/179 b/tests/qemu-iotests/179 new file mode 100755 index 0000000..338a45d --- /dev/null +++ b/tests/qemu-iotests/179 @@ -0,0 +1,78 @@ +#!/bin/bash +# +# Test case for write zeroes with unmap +# +# Copyright (C) 2017 Red Hat, Inc. +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. +# + +# creator +owner=ebl...@redhat.com + +seq="$(basename $0)" +echo "QA output created by $seq" + +here="$PWD" +status=1 # failure is the default! + +_cleanup() +{ + _cleanup_test_img +} +trap "_cleanup; exit \$status" 0 1 2 3 15 + +# get standard environment, filters and checks +. ./common.rc +. ./common.filter + +_supported_fmt qcow2 +_supported_proto file +_supported_os Linux + +echo +echo '=== Testing write zeroes with unmap ===' +echo + +TEST_IMG="$TEST_IMG.base" _make_test_img 16M +_make_test_img -b "$TEST_IMG.base" + +# Aligned writes should not allocate clusters, if unmap is requested +# and there is no backing file. +$QEMU_IO -c "write -z -u 1M 1M" "$TEST_IMG.base" | _filter_qemu_io + +# Unmap can even clear previously-allocated clusters. +$QEMU_IO -c "write 3M 1M" "$TEST_IMG.base" | _filter_qemu_io +$QEMU_IO -c "write -z -u 3M 1M" "$TEST_IMG.base" | _filter_qemu_io + +# Up to now, the entire image should still be unallocated. +$QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map + +# But not requesting unmap must result in allocation (whether a cluster +# allocation in compat=0.10 or a flag allocation in compat=1.1). +$QEMU_IO -c "write -z 5M 1M" "$TEST_IMG.base" | _filter_qemu_io +$QEMU_IO -c "alloc 5M $((1024*1024 / 512))" "$TEST_IMG.base" | _filter_qemu_io + +# Presence of a backing file overrides permission to unmap. Again, +# compat=0.10 images allocate, while compat=1.1 images set zero flag. +$QEMU_IO -c "write -z -u 7M 1M" "$TEST_IMG" | _filter_qemu_io +$QEMU_IO -c "alloc 7M $((1024 * 1024 / 512))" "$TEST_IMG" | _filter_qemu_io + +# Final check that images are still sane. +TEST_IMG="$TEST_IMG.base" _check_test_img +_check_test_img + +# success, all done +echo '*** done' +status=0 diff --git a/tests/qemu-iotests/179.out b/tests/qemu-iotests/179.out new file mode 100644 index 0000000..fc97b19 --- /dev/null +++ b/tests/qemu-iotests/179.out @@ -0,0 +1,22 @@ +QA output created by 179 + +=== Testing write zeroes with unmap === + +Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=16777216 +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=16777216 backing_file=TEST_DIR/t.IMGFMT.base +wrote 1048576/1048576 bytes at offset 1048576 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 1048576/1048576 bytes at offset 3145728 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 1048576/1048576 bytes at offset 3145728 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +[{ "start": 0, "length": 16777216, "depth": 1, "zero": true, "data": false}] +wrote 1048576/1048576 bytes at offset 5242880 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +2048/2048 sectors allocated at offset 5 MiB +wrote 1048576/1048576 bytes at offset 7340032 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +2048/2048 sectors allocated at offset 7 MiB +No errors were found on the image. +No errors were found on the image. +*** done diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group index 43142dd..cfc8823 100644 --- a/tests/qemu-iotests/group +++ b/tests/qemu-iotests/group @@ -169,3 +169,4 @@ 174 auto 175 auto quick 176 rw auto backing +179 rw auto quick -- 2.9.3
