xref: /qemu/tests/qemu-iotests/112 (revision abff1abf)
1#!/usr/bin/env bash
2#
3# Test cases for different refcount_bits values
4#
5# Copyright (C) 2015 Red Hat, Inc.
6#
7# This program is free software; you can redistribute it and/or modify
8# it under the terms of the GNU General Public License as published by
9# the Free Software Foundation; either version 2 of the License, or
10# (at your option) any later version.
11#
12# This program is distributed in the hope that it will be useful,
13# but WITHOUT ANY WARRANTY; without even the implied warranty of
14# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15# GNU General Public License for more details.
16#
17# You should have received a copy of the GNU General Public License
18# along with this program.  If not, see <http://www.gnu.org/licenses/>.
19#
20
21# creator
22owner=mreitz@redhat.com
23
24seq="$(basename $0)"
25echo "QA output created by $seq"
26
27status=1	# failure is the default!
28
29_cleanup()
30{
31	_cleanup_test_img
32}
33trap "_cleanup; exit \$status" 0 1 2 3 15
34
35# get standard environment, filters and checks
36. ./common.rc
37. ./common.filter
38
39# This tests qcow2-specific low-level functionality
40_supported_fmt qcow2
41_supported_proto file
42# This test will set refcount_bits on its own which would conflict with the
43# manual setting; compat will be overridden as well;
44# and external data files do not work well with our refcount testing
45_unsupported_imgopts refcount_bits 'compat=0.10' data_file
46
47print_refcount_bits()
48{
49    $QEMU_IMG info "$TEST_IMG" | sed -n '/refcount bits:/ s/^ *//p'
50}
51
52echo
53echo '=== refcount_bits limits ==='
54echo
55
56# Must be positive (non-zero)
57_make_test_img -o "refcount_bits=0" 64M
58# Must be positive (non-negative)
59_make_test_img -o "refcount_bits=-1" 64M
60# May not exceed 64
61_make_test_img -o "refcount_bits=128" 64M
62# Must be a power of two
63_make_test_img -o "refcount_bits=42" 64M
64
65# 1 is the minimum
66_make_test_img -o "refcount_bits=1" 64M
67print_refcount_bits
68
69# 64 is the maximum
70_make_test_img -o "refcount_bits=64" 64M
71print_refcount_bits
72
73# 16 is the default
74_make_test_img 64M
75print_refcount_bits
76
77echo
78echo '=== refcount_bits and compat=0.10 ==='
79echo
80
81# Should work
82_make_test_img -o "compat=0.10,refcount_bits=16" 64M
83print_refcount_bits
84
85# Should not work
86_make_test_img -o "compat=0.10,refcount_bits=1" 64M
87_make_test_img -o "compat=0.10,refcount_bits=64" 64M
88
89
90echo
91echo '=== Snapshot limit on refcount_bits=1 ==='
92echo
93
94_make_test_img -o "refcount_bits=1" 64M
95print_refcount_bits
96
97$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
98
99# Should fail for now; in the future, this might be supported by automatically
100# copying all clusters with overflowing refcount
101$QEMU_IMG snapshot -c foo "$TEST_IMG"
102
103# The new L1 table could/should be leaked
104_check_test_img
105
106echo
107echo '=== Snapshot limit on refcount_bits=2 ==='
108echo
109
110_make_test_img -o "refcount_bits=2" 64M
111print_refcount_bits
112
113$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
114
115# Should succeed
116$QEMU_IMG snapshot -c foo "$TEST_IMG"
117$QEMU_IMG snapshot -c bar "$TEST_IMG"
118# Should fail (4th reference)
119$QEMU_IMG snapshot -c baz "$TEST_IMG"
120
121# The new L1 table could/should be leaked
122_check_test_img
123
124echo
125echo '=== Compressed clusters with refcount_bits=1 ==='
126echo
127
128_make_test_img -o "refcount_bits=1" 64M
129print_refcount_bits
130
131# Both should fit into a single host cluster; instead of failing to increase the
132# refcount of that cluster, qemu should just allocate a new cluster and make
133# this operation succeed
134$QEMU_IO -c 'write -P 0 -c  0  64k' \
135         -c 'write -P 1 -c 64k 64k' \
136         "$TEST_IMG" | _filter_qemu_io
137
138_check_test_img
139
140echo
141echo '=== MSb set in 64 bit refcount ==='
142echo
143
144_make_test_img -o "refcount_bits=64" 64M
145print_refcount_bits
146
147$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
148
149# Set the MSb in the refblock entry of the data cluster
150poke_file "$TEST_IMG" $((0x20028)) "\x80\x00\x00\x00\x00\x00\x00\x00"
151
152# Clear OFLAG_COPIED in the L2 entry of the data cluster
153poke_file "$TEST_IMG" $((0x40000)) "\x00\x00\x00\x00\x00\x05\x00\x00"
154
155# Try to write to that cluster (should work, even though the MSb is set)
156$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
157
158echo
159echo '=== Snapshot on maximum 64 bit refcount value ==='
160echo
161
162_make_test_img -o "refcount_bits=64" 64M
163print_refcount_bits
164
165$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
166
167# Set the refblock entry to the maximum value possible
168poke_file "$TEST_IMG" $((0x20028)) "\xff\xff\xff\xff\xff\xff\xff\xff"
169
170# Clear OFLAG_COPIED in the L2 entry of the data cluster
171poke_file "$TEST_IMG" $((0x40000)) "\x00\x00\x00\x00\x00\x05\x00\x00"
172
173# Try a snapshot (should correctly identify the overflow; may work in the future
174# by falling back to COW)
175$QEMU_IMG snapshot -c foo "$TEST_IMG"
176
177# The new L1 table could/should be leaked; and obviously the data cluster is
178# leaked (refcount=UINT64_MAX reference=1)
179_check_test_img
180
181echo
182echo '=== Amend from refcount_bits=16 to refcount_bits=1 ==='
183echo
184
185_make_test_img 64M
186print_refcount_bits
187
188$QEMU_IO -c 'write 16M 32M' "$TEST_IMG" | _filter_qemu_io
189$QEMU_IMG amend -o refcount_bits=1 "$TEST_IMG"
190_check_test_img
191print_refcount_bits
192
193echo
194echo '=== Amend from refcount_bits=1 to refcount_bits=64 ==='
195echo
196
197$QEMU_IMG amend -o refcount_bits=64 "$TEST_IMG"
198_check_test_img
199print_refcount_bits
200
201echo
202echo '=== Amend to compat=0.10 ==='
203echo
204
205# Should not work because refcount_bits needs to be 16 for compat=0.10
206$QEMU_IMG amend -o compat=0.10 "$TEST_IMG"
207print_refcount_bits
208# Should work
209$QEMU_IMG amend -o compat=0.10,refcount_bits=16 "$TEST_IMG"
210_check_test_img
211print_refcount_bits
212
213# Get back to compat=1.1 and refcount_bits=16
214$QEMU_IMG amend -o compat=1.1 "$TEST_IMG"
215print_refcount_bits
216# Should not work
217$QEMU_IMG amend -o refcount_bits=32,compat=0.10 "$TEST_IMG"
218print_refcount_bits
219
220echo
221echo '=== Amend with snapshot ==='
222echo
223
224$QEMU_IMG snapshot -c foo "$TEST_IMG"
225# Just to have different refcounts across the image
226$QEMU_IO -c 'write 0 16M' "$TEST_IMG" | _filter_qemu_io
227
228# Should not work (may work in the future by first decreasing all refcounts so
229# they fit into the target range by copying them)
230$QEMU_IMG amend -o refcount_bits=1 "$TEST_IMG"
231_check_test_img
232print_refcount_bits
233
234# Should work
235$QEMU_IMG amend -o refcount_bits=2 "$TEST_IMG"
236_check_test_img
237print_refcount_bits
238
239echo
240echo '=== Testing too many references for check ==='
241echo
242
243_make_test_img -o "refcount_bits=1" 64M
244print_refcount_bits
245
246# This cluster should be created at 0x50000
247$QEMU_IO -c 'write 0 64k' "$TEST_IMG" | _filter_qemu_io
248# Now make the second L2 entry (the L2 table should be at 0x40000) point to that
249# cluster, so we have two references
250poke_file "$TEST_IMG" $((0x40008)) "\x80\x00\x00\x00\x00\x05\x00\x00"
251
252# This should say "please use amend"
253_check_test_img -r all
254
255# So we do that
256$QEMU_IMG amend -o refcount_bits=2 "$TEST_IMG"
257print_refcount_bits
258
259# And try again
260_check_test_img -r all
261
262echo
263echo '=== Multiple walks necessary during amend ==='
264echo
265
266_make_test_img -o "refcount_bits=1,cluster_size=512" 64k
267
268# Cluster 0 is the image header, clusters 1 to 4 are used by the L1 table, a
269# single L2 table, the reftable and a single refblock. This creates 58 data
270# clusters (actually, the L2 table is created here, too), so in total there are
271# then 63 used clusters in the image. With a refcount width of 64, one refblock
272# describes 64 clusters (512 bytes / 64 bits/entry = 64 entries), so this will
273# make the first refblock in the amended image have exactly one free entry.
274$QEMU_IO -c "write 0 $((58 * 512))" "$TEST_IMG" | _filter_qemu_io
275
276# Now change the refcount width; since the first new refblock will have exactly
277# one free entry, that entry will be used to store its own reference. No other
278# refblocks are needed, so then the new reftable will be allocated; since the
279# first new refblock is completely filled up, this will require a new refblock
280# which is why the refcount width changing function will need to run through
281# everything one more time until the allocations are stable.
282# Having more walks than usual should be visible as regressing progress (from
283# 66.67 % (2/3 walks) to 50.00 % (2/4 walks)).
284$QEMU_IMG amend -o refcount_bits=64 -p "$TEST_IMG" | tr '\r' '\n' \
285                                                   | grep -A 1 '66.67'
286print_refcount_bits
287
288_check_test_img
289
290
291# success, all done
292echo '*** done'
293rm -f $seq.full
294status=0
295