tests/qemu-iotests/112

   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
  23 owner=mreitz@redhat.com
  24
  25 seq="$(basename $0)"
  26 echo "QA output created by $seq"
  27
  28 status=1        # failure is the default!
  29
  30 _cleanup()
  31 {
  32         _cleanup_test_img
  33 }
  34 trap "_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 _unsupported_imgopts refcount_bits 'compat=0.10' data_file
  47
  48 print_refcount_bits()
  49 {
  50     $QEMU_IMG info "$TEST_IMG" | sed -n '/refcount bits:/ s/^ *//p'
  51 }
  52
  53 echo
  54 echo '=== refcount_bits limits ==='
  55 echo
  56
  57 # Must be positive (non-zero)
  58 _make_test_img -o "refcount_bits=0" 64M
  59 # Must be positive (non-negative)
  60 _make_test_img -o "refcount_bits=-1" 64M
  61 # May not exceed 64
  62 _make_test_img -o "refcount_bits=128" 64M
  63 # Must be a power of two
  64 _make_test_img -o "refcount_bits=42" 64M
  65
  66 # 1 is the minimum
  67 _make_test_img -o "refcount_bits=1" 64M
  68 print_refcount_bits
  69
  70 # 64 is the maximum
  71 _make_test_img -o "refcount_bits=64" 64M
  72 print_refcount_bits
  73
  74 # 16 is the default
  75 _make_test_img 64M
  76 print_refcount_bits
  77
  78 echo
  79 echo '=== refcount_bits and compat=0.10 ==='
  80 echo
  81
  82 # Should work
  83 _make_test_img -o "compat=0.10,refcount_bits=16" 64M
  84 print_refcount_bits
  85
  86 # Should not work
  87 _make_test_img -o "compat=0.10,refcount_bits=1" 64M
  88 _make_test_img -o "compat=0.10,refcount_bits=64" 64M
  89
  90
  91 echo
  92 echo '=== Snapshot limit on refcount_bits=1 ==='
  93 echo
  94
  95 _make_test_img -o "refcount_bits=1" 64M
  96 print_refcount_bits
  97
  98 $QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
  99
 100 # Should fail for now; in the future, this might be supported by automatically
 101 # copying all clusters with overflowing refcount
 102 $QEMU_IMG snapshot -c foo "$TEST_IMG"
 103
 104 # The new L1 table could/should be leaked
 105 _check_test_img
 106
 107 echo
 108 echo '=== Snapshot limit on refcount_bits=2 ==='
 109 echo
 110
 111 _make_test_img -o "refcount_bits=2" 64M
 112 print_refcount_bits
 113
 114 $QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
 115
 116 # Should succeed
 117 $QEMU_IMG snapshot -c foo "$TEST_IMG"
 118 $QEMU_IMG snapshot -c bar "$TEST_IMG"
 119 # Should fail (4th reference)
 120 $QEMU_IMG snapshot -c baz "$TEST_IMG"
 121
 122 # The new L1 table could/should be leaked
 123 _check_test_img
 124
 125 echo
 126 echo '=== Compressed clusters with refcount_bits=1 ==='
 127 echo
 128
 129 _make_test_img -o "refcount_bits=1" 64M
 130 print_refcount_bits
 131
 132 # Both should fit into a single host cluster; instead of failing to increase the
 133 # refcount of that cluster, qemu should just allocate a new cluster and make
 134 # this operation succeed
 135 $QEMU_IO -c 'write -P 0 -c  0  64k' \
 136          -c 'write -P 1 -c 64k 64k' \
 137          "$TEST_IMG" | _filter_qemu_io
 138
 139 _check_test_img
 140
 141 echo
 142 echo '=== MSb set in 64 bit refcount ==='
 143 echo
 144
 145 _make_test_img -o "refcount_bits=64" 64M
 146 print_refcount_bits
 147
 148 $QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
 149
 150 # Set the MSb in the refblock entry of the data cluster
 151 poke_file "$TEST_IMG" $((0x20028)) "\x80\x00\x00\x00\x00\x00\x00\x00"
 152
 153 # Clear OFLAG_COPIED in the L2 entry of the data cluster
 154 poke_file "$TEST_IMG" $((0x40000)) "\x00\x00\x00\x00\x00\x05\x00\x00"
 155
 156 # Try to write to that cluster (should work, even though the MSb is set)
 157 $QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
 158
 159 echo
 160 echo '=== Snapshot on maximum 64 bit refcount value ==='
 161 echo
 162
 163 _make_test_img -o "refcount_bits=64" 64M
 164 print_refcount_bits
 165
 166 $QEMU_IO -c 'write 0 512' "$TEST_IMG" | _filter_qemu_io
 167
 168 # Set the refblock entry to the maximum value possible
 169 poke_file "$TEST_IMG" $((0x20028)) "\xff\xff\xff\xff\xff\xff\xff\xff"
 170
 171 # Clear OFLAG_COPIED in the L2 entry of the data cluster
 172 poke_file "$TEST_IMG" $((0x40000)) "\x00\x00\x00\x00\x00\x05\x00\x00"
 173
 174 # Try a snapshot (should correctly identify the overflow; may work in the future
 175 # by falling back to COW)
 176 $QEMU_IMG snapshot -c foo "$TEST_IMG"
 177
 178 # The new L1 table could/should be leaked; and obviously the data cluster is
 179 # leaked (refcount=UINT64_MAX reference=1)
 180 _check_test_img
 181
 182 echo
 183 echo '=== Amend from refcount_bits=16 to refcount_bits=1 ==='
 184 echo
 185
 186 _make_test_img 64M
 187 print_refcount_bits
 188
 189 $QEMU_IO -c 'write 16M 32M' "$TEST_IMG" | _filter_qemu_io
 190 $QEMU_IMG amend -o refcount_bits=1 "$TEST_IMG"
 191 _check_test_img
 192 print_refcount_bits
 193
 194 echo
 195 echo '=== Amend from refcount_bits=1 to refcount_bits=64 ==='
 196 echo
 197
 198 $QEMU_IMG amend -o refcount_bits=64 "$TEST_IMG"
 199 _check_test_img
 200 print_refcount_bits
 201
 202 echo
 203 echo '=== Amend to compat=0.10 ==='
 204 echo
 205
 206 # Should not work because refcount_bits needs to be 16 for compat=0.10
 207 $QEMU_IMG amend -o compat=0.10 "$TEST_IMG"
 208 print_refcount_bits
 209 # Should work
 210 $QEMU_IMG amend -o compat=0.10,refcount_bits=16 "$TEST_IMG"
 211 _check_test_img
 212 print_refcount_bits
 213
 214 # Get back to compat=1.1 and refcount_bits=16
 215 $QEMU_IMG amend -o compat=1.1 "$TEST_IMG"
 216 print_refcount_bits
 217 # Should not work
 218 $QEMU_IMG amend -o refcount_bits=32,compat=0.10 "$TEST_IMG"
 219 print_refcount_bits
 220
 221 echo
 222 echo '=== Amend with snapshot ==='
 223 echo
 224
 225 $QEMU_IMG snapshot -c foo "$TEST_IMG"
 226 # Just to have different refcounts across the image
 227 $QEMU_IO -c 'write 0 16M' "$TEST_IMG" | _filter_qemu_io
 228
 229 # Should not work (may work in the future by first decreasing all refcounts so
 230 # they fit into the target range by copying them)
 231 $QEMU_IMG amend -o refcount_bits=1 "$TEST_IMG"
 232 _check_test_img
 233 print_refcount_bits
 234
 235 # Should work
 236 $QEMU_IMG amend -o refcount_bits=2 "$TEST_IMG"
 237 _check_test_img
 238 print_refcount_bits
 239
 240 echo
 241 echo '=== Testing too many references for check ==='
 242 echo
 243
 244 _make_test_img -o "refcount_bits=1" 64M
 245 print_refcount_bits
 246
 247 # This cluster should be created at 0x50000
 248 $QEMU_IO -c 'write 0 64k' "$TEST_IMG" | _filter_qemu_io
 249 # Now make the second L2 entry (the L2 table should be at 0x40000) point to that
 250 # cluster, so we have two references
 251 poke_file "$TEST_IMG" $((0x40008)) "\x80\x00\x00\x00\x00\x05\x00\x00"
 252
 253 # This should say "please use amend"
 254 _check_test_img -r all
 255
 256 # So we do that
 257 $QEMU_IMG amend -o refcount_bits=2 "$TEST_IMG"
 258 print_refcount_bits
 259
 260 # And try again
 261 _check_test_img -r all
 262
 263 echo
 264 echo '=== Multiple walks necessary during amend ==='
 265 echo
 266
 267 _make_test_img -o "refcount_bits=1,cluster_size=512" 64k
 268
 269 # Cluster 0 is the image header, clusters 1 to 4 are used by the L1 table, a
 270 # single L2 table, the reftable and a single refblock. This creates 58 data
 271 # clusters (actually, the L2 table is created here, too), so in total there are
 272 # then 63 used clusters in the image. With a refcount width of 64, one refblock
 273 # describes 64 clusters (512 bytes / 64 bits/entry = 64 entries), so this will
 274 # make the first refblock in the amended image have exactly one free entry.
 275 $QEMU_IO -c "write 0 $((58 * 512))" "$TEST_IMG" | _filter_qemu_io
 276
 277 # Now change the refcount width; since the first new refblock will have exactly
 278 # one free entry, that entry will be used to store its own reference. No other
 279 # refblocks are needed, so then the new reftable will be allocated; since the
 280 # first new refblock is completely filled up, this will require a new refblock
 281 # which is why the refcount width changing function will need to run through
 282 # everything one more time until the allocations are stable.
 283 # Having more walks than usual should be visible as regressing progress (from
 284 # 66.67 % (2/3 walks) to 50.00 % (2/4 walks)).
 285 $QEMU_IMG amend -o refcount_bits=64 -p "$TEST_IMG" | tr '\r' '\n' \
 286                                                    | grep -A 1 '66.67'
 287 print_refcount_bits
 288
 289 _check_test_img
 290
 291
 292 # success, all done
 293 echo '*** done'
 294 rm -f $seq.full
 295 status=0