xref: /qemu/tests/qemu-iotests/112 (revision a976a99a)
1#!/usr/bin/env bash
2# group: rw
3#
4# Test cases for different refcount_bits values
5#
6# Copyright (C) 2015 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=hreitz@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# This tests qcow2-specific low-level functionality
41_supported_fmt qcow2
42_supported_proto file fuse
43# This test will set refcount_bits on its own which would conflict with the
44# manual setting; compat will be overridden as well;
45# and external data files do not work well with our refcount testing
46# also, compression type is not supported with compat=0.10 used in test
47_unsupported_imgopts refcount_bits 'compat=0.10' data_file compression_type
48
49print_refcount_bits()
50{
51    $QEMU_IMG info "$TEST_IMG" | sed -n '/refcount bits:/ s/^ *//p'
52}
53
54echo
55echo '=== refcount_bits limits ==='
56echo
57
58# Must be positive (non-zero)
59_make_test_img -o "refcount_bits=0" 64M
60# Must be positive (non-negative)
61_make_test_img -o "refcount_bits=-1" 64M
62# May not exceed 64
63_make_test_img -o "refcount_bits=128" 64M
64# Must be a power of two
65_make_test_img -o "refcount_bits=42" 64M
66
67# 1 is the minimum
68_make_test_img -o "refcount_bits=1" 64M
69print_refcount_bits
70
71# 64 is the maximum
72_make_test_img -o "refcount_bits=64" 64M
73print_refcount_bits
74
75# 16 is the default
76_make_test_img 64M
77print_refcount_bits
78
79echo
80echo '=== refcount_bits and compat=0.10 ==='
81echo
82
83# Should work
84_make_test_img -o "compat=0.10,refcount_bits=16" 64M
85print_refcount_bits
86
87# Should not work
88_make_test_img -o "compat=0.10,refcount_bits=1" 64M
89_make_test_img -o "compat=0.10,refcount_bits=64" 64M
90
91
92echo
93echo '=== Snapshot limit on refcount_bits=1 ==='
94echo
95
96_make_test_img -o "refcount_bits=1" 64M
97print_refcount_bits
98
99$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
100
101# Should fail for now; in the future, this might be supported by automatically
102# copying all clusters with overflowing refcount
103$QEMU_IMG snapshot -c foo "$TEST_IMG"
104
105# The new L1 table could/should be leaked
106_check_test_img
107
108echo
109echo '=== Snapshot limit on refcount_bits=2 ==='
110echo
111
112_make_test_img -o "refcount_bits=2" 64M
113print_refcount_bits
114
115$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
116
117# Should succeed
118$QEMU_IMG snapshot -c foo "$TEST_IMG"
119$QEMU_IMG snapshot -c bar "$TEST_IMG"
120# Should fail (4th reference)
121$QEMU_IMG snapshot -c baz "$TEST_IMG"
122
123# The new L1 table could/should be leaked
124_check_test_img
125
126echo
127echo '=== Compressed clusters with refcount_bits=1 ==='
128echo
129
130_make_test_img -o "refcount_bits=1" 64M
131print_refcount_bits
132
133# Both should fit into a single host cluster; instead of failing to increase the
134# refcount of that cluster, qemu should just allocate a new cluster and make
135# this operation succeed
136$QEMU_IO -c 'write -P 0 -c  0  64k' \
137         -c 'write -P 1 -c 64k 64k' \
138         "$TEST_IMG" | _filter_qemu_io
139
140_check_test_img
141
142echo
143echo '=== MSb set in 64 bit refcount ==='
144echo
145
146_make_test_img -o "refcount_bits=64" 64M
147print_refcount_bits
148
149$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
150
151# Set the MSb in the refblock entry of the data cluster
152poke_file "$TEST_IMG" $((0x20028)) "\x80\x00\x00\x00\x00\x00\x00\x00"
153
154# Clear OFLAG_COPIED in the L2 entry of the data cluster
155poke_file "$TEST_IMG" $((0x40000)) "\x00\x00\x00\x00\x00\x05\x00\x00"
156
157# Try to write to that cluster (should work, even though the MSb is set)
158$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
159
160echo
161echo '=== Snapshot on maximum 64 bit refcount value ==='
162echo
163
164_make_test_img -o "refcount_bits=64" 64M
165print_refcount_bits
166
167$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
168
169# Set the refblock entry to the maximum value possible
170poke_file "$TEST_IMG" $((0x20028)) "\xff\xff\xff\xff\xff\xff\xff\xff"
171
172# Clear OFLAG_COPIED in the L2 entry of the data cluster
173poke_file "$TEST_IMG" $((0x40000)) "\x00\x00\x00\x00\x00\x05\x00\x00"
174
175# Try a snapshot (should correctly identify the overflow; may work in the future
176# by falling back to COW)
177$QEMU_IMG snapshot -c foo "$TEST_IMG"
178
179# The new L1 table could/should be leaked; and obviously the data cluster is
180# leaked (refcount=UINT64_MAX reference=1)
181_check_test_img
182
183echo
184echo '=== Amend from refcount_bits=16 to refcount_bits=1 ==='
185echo
186
187_make_test_img 64M
188print_refcount_bits
189
190$QEMU_IO -c 'write 16M 32M' "$TEST_IMG" | _filter_qemu_io
191$QEMU_IMG amend -o refcount_bits=1 "$TEST_IMG"
192_check_test_img
193print_refcount_bits
194
195echo
196echo '=== Amend from refcount_bits=1 to refcount_bits=64 ==='
197echo
198
199$QEMU_IMG amend -o refcount_bits=64 "$TEST_IMG"
200_check_test_img
201print_refcount_bits
202
203echo
204echo '=== Amend to compat=0.10 ==='
205echo
206
207# Should not work because refcount_bits needs to be 16 for compat=0.10
208$QEMU_IMG amend -o compat=0.10 "$TEST_IMG"
209print_refcount_bits
210# Should work
211$QEMU_IMG amend -o compat=0.10,refcount_bits=16 "$TEST_IMG"
212_check_test_img
213print_refcount_bits
214
215# Get back to compat=1.1 and refcount_bits=16
216$QEMU_IMG amend -o compat=1.1 "$TEST_IMG"
217print_refcount_bits
218# Should not work
219$QEMU_IMG amend -o refcount_bits=32,compat=0.10 "$TEST_IMG"
220print_refcount_bits
221
222echo
223echo '=== Amend with snapshot ==='
224echo
225
226$QEMU_IMG snapshot -c foo "$TEST_IMG"
227# Just to have different refcounts across the image
228$QEMU_IO -c 'write 0 16M' "$TEST_IMG" | _filter_qemu_io
229
230# Should not work (may work in the future by first decreasing all refcounts so
231# they fit into the target range by copying them)
232$QEMU_IMG amend -o refcount_bits=1 "$TEST_IMG"
233_check_test_img
234print_refcount_bits
235
236# Should work
237$QEMU_IMG amend -o refcount_bits=2 "$TEST_IMG"
238_check_test_img
239print_refcount_bits
240
241echo
242echo '=== Testing too many references for check ==='
243echo
244
245_make_test_img -o "refcount_bits=1" 64M
246print_refcount_bits
247
248# This cluster should be created at 0x50000
249$QEMU_IO -c 'write 0 64k' "$TEST_IMG" | _filter_qemu_io
250# Now make the second L2 entry (the L2 table should be at 0x40000) point to that
251# cluster, so we have two references
252poke_file "$TEST_IMG" $((0x40008)) "\x80\x00\x00\x00\x00\x05\x00\x00"
253
254# This should say "please use amend"
255_check_test_img -r all
256
257# So we do that
258$QEMU_IMG amend -o refcount_bits=2 "$TEST_IMG"
259print_refcount_bits
260
261# And try again
262_check_test_img -r all
263
264echo
265echo '=== Multiple walks necessary during amend ==='
266echo
267
268_make_test_img -o "refcount_bits=1,cluster_size=512" 64k
269
270# Cluster 0 is the image header, clusters 1 to 4 are used by the L1 table, a
271# single L2 table, the reftable and a single refblock. This creates 58 data
272# clusters (actually, the L2 table is created here, too), so in total there are
273# then 63 used clusters in the image. With a refcount width of 64, one refblock
274# describes 64 clusters (512 bytes / 64 bits/entry = 64 entries), so this will
275# make the first refblock in the amended image have exactly one free entry.
276$QEMU_IO -c "write 0 $((58 * 512))" "$TEST_IMG" | _filter_qemu_io
277
278# Now change the refcount width; since the first new refblock will have exactly
279# one free entry, that entry will be used to store its own reference. No other
280# refblocks are needed, so then the new reftable will be allocated; since the
281# first new refblock is completely filled up, this will require a new refblock
282# which is why the refcount width changing function will need to run through
283# everything one more time until the allocations are stable.
284# Having more walks than usual should be visible as regressing progress (from
285# 66.67 % (2/3 walks) to 50.00 % (2/4 walks)).
286$QEMU_IMG amend -o refcount_bits=64 -p "$TEST_IMG" | tr '\r' '\n' \
287                                                   | grep -A 1 '66.67'
288print_refcount_bits
289
290_check_test_img
291
292
293# success, all done
294echo '*** done'
295rm -f $seq.full
296status=0
297