xref: /openbmc/qemu/tests/qemu-iotests/115 (revision b91a0fa7)
1#!/usr/bin/env bash
2# group: rw
3#
4# Test case for non-self-referential qcow2 refcount blocks
5#
6# Copyright (C) 2014 Red Hat, Inc.
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=mreitz@redhat.com
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# This test relies on refcounts being 64 bits wide (which does not work with
43# compat=0.10)
44_unsupported_imgopts 'refcount_bits=\([^6]\|.\([^4]\|$\)\)' 'compat=0.10'
45
46echo
47echo '=== Testing large refcount and L1 table ==='
48echo
49
50# Create an image with an L1 table and a refcount table that each span twice the
51# number of clusters which can be described by a single refblock; therefore, at
52# least two refblocks cannot count their own refcounts because all the clusters
53# they describe are part of the L1 table or refcount table.
54
55# One refblock can describe (with cluster_size=512 and refcount_bits=64)
56# 512/8 = 64 clusters, therefore the L1 table should cover 128 clusters, which
57# equals 128 * (512/8) = 8192 entries (actually, 8192 - 512/8 = 8129 would
58# suffice, but it does not really matter). 8192 L2 tables can in turn describe
59# 8192 * 512/8 = 524,288 clusters which cover a space of 256 MB.
60
61# Since with refcount_bits=64 every refcount block entry is 64 bits wide (just
62# like the L2 table entries), the same calculation applies to the refcount table
63# as well; the difference is that while for the L1 table the guest disk size is
64# concerned, for the refcount table it is the image length that has to be at
65# least 256 MB. We can achieve that by using preallocation=metadata for an image
66# which has a guest disk size of 256 MB.
67
68_make_test_img -o "refcount_bits=64,cluster_size=512,preallocation=metadata" 256M
69
70# We know for sure that the L1 and refcount tables do not overlap with any other
71# structure because the metadata overlap checks would have caught that case.
72
73# Because qemu refuses to open qcow2 files whose L1 table does not cover the
74# whole guest disk size, it is definitely large enough. On the other hand, to
75# test whether the refcount table is large enough, we simply have to verify that
76# indeed all the clusters are allocated, which is done by qemu-img check.
77
78# The final thing we need to test is whether the tables are actually covered by
79# refcount blocks; since all clusters of the tables are referenced, we can use
80# qemu-img check for that purpose, too.
81
82$QEMU_IMG check "$TEST_IMG" | \
83    sed -e 's/^.* = \([0-9]\+\.[0-9]\+% allocated\).*\(clusters\)$/\1 \2/' \
84        -e '/^Image end offset/d'
85
86# (Note that we cannot use _check_test_img because that function filters out the
87# allocation status)
88
89# success, all done
90echo '*** done'
91rm -f $seq.full
92status=0
93