xref: /qemu/tests/qemu-iotests/112 (revision ab9056ff)
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_unsupported_imgopts refcount_bits 'compat=0.10'
45
46print_refcount_bits()
47{
48    $QEMU_IMG info "$TEST_IMG" | sed -n '/refcount bits:/ s/^ *//p'
49}
50
51echo
52echo '=== refcount_bits limits ==='
53echo
54
55# Must be positive (non-zero)
56IMGOPTS="$IMGOPTS,refcount_bits=0" _make_test_img 64M
57# Must be positive (non-negative)
58IMGOPTS="$IMGOPTS,refcount_bits=-1" _make_test_img 64M
59# May not exceed 64
60IMGOPTS="$IMGOPTS,refcount_bits=128" _make_test_img 64M
61# Must be a power of two
62IMGOPTS="$IMGOPTS,refcount_bits=42" _make_test_img 64M
63
64# 1 is the minimum
65IMGOPTS="$IMGOPTS,refcount_bits=1" _make_test_img 64M
66print_refcount_bits
67
68# 64 is the maximum
69IMGOPTS="$IMGOPTS,refcount_bits=64" _make_test_img 64M
70print_refcount_bits
71
72# 16 is the default
73_make_test_img 64M
74print_refcount_bits
75
76echo
77echo '=== refcount_bits and compat=0.10 ==='
78echo
79
80# Should work
81IMGOPTS="$IMGOPTS,compat=0.10,refcount_bits=16" _make_test_img 64M
82print_refcount_bits
83
84# Should not work
85IMGOPTS="$IMGOPTS,compat=0.10,refcount_bits=1" _make_test_img 64M
86IMGOPTS="$IMGOPTS,compat=0.10,refcount_bits=64" _make_test_img 64M
87
88
89echo
90echo '=== Snapshot limit on refcount_bits=1 ==='
91echo
92
93IMGOPTS="$IMGOPTS,refcount_bits=1" _make_test_img 64M
94print_refcount_bits
95
96$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
97
98# Should fail for now; in the future, this might be supported by automatically
99# copying all clusters with overflowing refcount
100$QEMU_IMG snapshot -c foo "$TEST_IMG"
101
102# The new L1 table could/should be leaked
103_check_test_img
104
105echo
106echo '=== Snapshot limit on refcount_bits=2 ==='
107echo
108
109IMGOPTS="$IMGOPTS,refcount_bits=2" _make_test_img 64M
110print_refcount_bits
111
112$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
113
114# Should succeed
115$QEMU_IMG snapshot -c foo "$TEST_IMG"
116$QEMU_IMG snapshot -c bar "$TEST_IMG"
117# Should fail (4th reference)
118$QEMU_IMG snapshot -c baz "$TEST_IMG"
119
120# The new L1 table could/should be leaked
121_check_test_img
122
123echo
124echo '=== Compressed clusters with refcount_bits=1 ==='
125echo
126
127IMGOPTS="$IMGOPTS,refcount_bits=1" _make_test_img 64M
128print_refcount_bits
129
130# Both should fit into a single host cluster; instead of failing to increase the
131# refcount of that cluster, qemu should just allocate a new cluster and make
132# this operation succeed
133$QEMU_IO -c 'write -P 0 -c  0  64k' \
134         -c 'write -P 1 -c 64k 64k' \
135         "$TEST_IMG" | _filter_qemu_io
136
137_check_test_img
138
139echo
140echo '=== MSb set in 64 bit refcount ==='
141echo
142
143IMGOPTS="$IMGOPTS,refcount_bits=64" _make_test_img 64M
144print_refcount_bits
145
146$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
147
148# Set the MSb in the refblock entry of the data cluster
149poke_file "$TEST_IMG" $((0x20028)) "\x80\x00\x00\x00\x00\x00\x00\x00"
150
151# Clear OFLAG_COPIED in the L2 entry of the data cluster
152poke_file "$TEST_IMG" $((0x40000)) "\x00\x00\x00\x00\x00\x05\x00\x00"
153
154# Try to write to that cluster (should work, even though the MSb is set)
155$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
156
157echo
158echo '=== Snapshot on maximum 64 bit refcount value ==='
159echo
160
161IMGOPTS="$IMGOPTS,refcount_bits=64" _make_test_img 64M
162print_refcount_bits
163
164$QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
165
166# Set the refblock entry to the maximum value possible
167poke_file "$TEST_IMG" $((0x20028)) "\xff\xff\xff\xff\xff\xff\xff\xff"
168
169# Clear OFLAG_COPIED in the L2 entry of the data cluster
170poke_file "$TEST_IMG" $((0x40000)) "\x00\x00\x00\x00\x00\x05\x00\x00"
171
172# Try a snapshot (should correctly identify the overflow; may work in the future
173# by falling back to COW)
174$QEMU_IMG snapshot -c foo "$TEST_IMG"
175
176# The new L1 table could/should be leaked; and obviously the data cluster is
177# leaked (refcount=UINT64_MAX reference=1)
178_check_test_img
179
180echo
181echo '=== Amend from refcount_bits=16 to refcount_bits=1 ==='
182echo
183
184_make_test_img 64M
185print_refcount_bits
186
187$QEMU_IO -c 'write 16M 32M' "$TEST_IMG" | _filter_qemu_io
188$QEMU_IMG amend -o refcount_bits=1 "$TEST_IMG"
189_check_test_img
190print_refcount_bits
191
192echo
193echo '=== Amend from refcount_bits=1 to refcount_bits=64 ==='
194echo
195
196$QEMU_IMG amend -o refcount_bits=64 "$TEST_IMG"
197_check_test_img
198print_refcount_bits
199
200echo
201echo '=== Amend to compat=0.10 ==='
202echo
203
204# Should not work because refcount_bits needs to be 16 for compat=0.10
205$QEMU_IMG amend -o compat=0.10 "$TEST_IMG"
206print_refcount_bits
207# Should work
208$QEMU_IMG amend -o compat=0.10,refcount_bits=16 "$TEST_IMG"
209_check_test_img
210print_refcount_bits
211
212# Get back to compat=1.1 and refcount_bits=16
213$QEMU_IMG amend -o compat=1.1 "$TEST_IMG"
214print_refcount_bits
215# Should not work
216$QEMU_IMG amend -o refcount_bits=32,compat=0.10 "$TEST_IMG"
217print_refcount_bits
218
219echo
220echo '=== Amend with snapshot ==='
221echo
222
223$QEMU_IMG snapshot -c foo "$TEST_IMG"
224# Just to have different refcounts across the image
225$QEMU_IO -c 'write 0 16M' "$TEST_IMG" | _filter_qemu_io
226
227# Should not work (may work in the future by first decreasing all refcounts so
228# they fit into the target range by copying them)
229$QEMU_IMG amend -o refcount_bits=1 "$TEST_IMG"
230_check_test_img
231print_refcount_bits
232
233# Should work
234$QEMU_IMG amend -o refcount_bits=2 "$TEST_IMG"
235_check_test_img
236print_refcount_bits
237
238echo
239echo '=== Testing too many references for check ==='
240echo
241
242IMGOPTS="$IMGOPTS,refcount_bits=1" _make_test_img 64M
243print_refcount_bits
244
245# This cluster should be created at 0x50000
246$QEMU_IO -c 'write 0 64k' "$TEST_IMG" | _filter_qemu_io
247# Now make the second L2 entry (the L2 table should be at 0x40000) point to that
248# cluster, so we have two references
249poke_file "$TEST_IMG" $((0x40008)) "\x80\x00\x00\x00\x00\x05\x00\x00"
250
251# This should say "please use amend"
252_check_test_img -r all
253
254# So we do that
255$QEMU_IMG amend -o refcount_bits=2 "$TEST_IMG"
256print_refcount_bits
257
258# And try again
259_check_test_img -r all
260
261echo
262echo '=== Multiple walks necessary during amend ==='
263echo
264
265IMGOPTS="$IMGOPTS,refcount_bits=1,cluster_size=512" _make_test_img 64k
266
267# Cluster 0 is the image header, clusters 1 to 4 are used by the L1 table, a
268# single L2 table, the reftable and a single refblock. This creates 58 data
269# clusters (actually, the L2 table is created here, too), so in total there are
270# then 63 used clusters in the image. With a refcount width of 64, one refblock
271# describes 64 clusters (512 bytes / 64 bits/entry = 64 entries), so this will
272# make the first refblock in the amended image have exactly one free entry.
273$QEMU_IO -c "write 0 $((58 * 512))" "$TEST_IMG" | _filter_qemu_io
274
275# Now change the refcount width; since the first new refblock will have exactly
276# one free entry, that entry will be used to store its own reference. No other
277# refblocks are needed, so then the new reftable will be allocated; since the
278# first new refblock is completely filled up, this will require a new refblock
279# which is why the refcount width changing function will need to run through
280# everything one more time until the allocations are stable.
281# Having more walks than usual should be visible as regressing progress (from
282# 66.67 % (2/3 walks) to 50.00 % (2/4 walks)).
283$QEMU_IMG amend -o refcount_bits=64 -p "$TEST_IMG" | tr '\r' '\n' \
284                                                   | grep -A 1 '66.67'
285print_refcount_bits
286
287_check_test_img
288
289
290# success, all done
291echo '*** done'
292rm -f $seq.full
293status=0
294