xref: /qemu/tests/qemu-iotests/250 (revision ca61e750)
1#!/usr/bin/env bash
2# group: rw quick
3#
4# Test big discard in qcow2 shrink
5#
6# Copyright (c) 2019 Virtuozzo International GmbH. All rights reserved.
7#
8# This program is free software; you can redistribute it and/or modify
9# it under the terms of the GNU General Public License as published by
10# the Free Software Foundation; either version 2 of the License, or
11# (at your option) any later version.
12#
13# This program is distributed in the hope that it will be useful,
14# but WITHOUT ANY WARRANTY; without even the implied warranty of
15# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16# GNU General Public License for more details.
17#
18# You should have received a copy of the GNU General Public License
19# along with this program.  If not, see <http://www.gnu.org/licenses/>.
20#
21
22# creator
23owner=v.sementsov-og@mail.ru
24
25seq=`basename $0`
26echo "QA output created by $seq"
27
28status=1	# failure is the default!
29
30_cleanup()
31{
32    _cleanup_test_img
33}
34trap "_cleanup; exit \$status" 0 1 2 3 15
35
36# get standard environment, filters and checks
37. ./common.rc
38. ./common.filter
39
40_supported_fmt qcow2
41_supported_proto file fuse
42_supported_os Linux
43# This test does not make much sense with external data files
44_unsupported_imgopts data_file
45
46# This test checks that qcow2_process_discards does not truncate a discard
47# request > 2G.
48# To reproduce bug we need to overflow int by one sequential discard, so we
49# need size > 2G, bigger cluster size (as with default 64k we may have maximum
50# of 512M sequential data, corresponding to one L1 entry), and we need some
51# data of the beginning of the disk mapped to the end of file to prevent
52# bdrv_co_truncate(bs->file) call in qcow2_co_truncate(), which might succeed
53# anyway.
54
55disk_usage()
56{
57    du --block-size=1 $1 | awk '{print $1}'
58}
59
60size=2100M
61
62_make_test_img -o "cluster_size=1M,preallocation=metadata" $size
63$QEMU_IO -c 'discard 0 10M' -c 'discard 2090M 10M' \
64         -c 'write 2090M 10M' -c 'write 0 10M' "$TEST_IMG" | _filter_qemu_io
65
66# Check that our trick with swapping first and last 10M chunks succeeded.
67# Otherwise test may pass even if bdrv_pdiscard() fails in
68# qcow2_process_discards()
69$QEMU_IMG map "$TEST_IMG" | _filter_testdir
70
71before=$(disk_usage "$TEST_IMG")
72$QEMU_IMG resize --shrink "$TEST_IMG" 5M
73after=$(disk_usage "$TEST_IMG")
74
75echo "Disk usage delta: $((before - after))"
76
77# success, all done
78echo "*** done"
79rm -f $seq.full
80status=0
81