tests/qemu-iotests/112

   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
  22 owner=mreitz@redhat.com
  23
  24 seq="$(basename $0)"
  25 echo "QA output created by $seq"
  26
  27 status=1        # failure is the default!
  28
  29 _cleanup()
  30 {
  31         _cleanup_test_img
  32 }
  33 trap "_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
  47 print_refcount_bits()
  48 {
  49     $QEMU_IMG info "$TEST_IMG" | sed -n '/refcount bits:/ s/^ *//p'
  50 }
  51
  52 echo
  53 echo '=== refcount_bits limits ==='
  54 echo
  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
  67 print_refcount_bits
  68
  69 # 64 is the maximum
  70 _make_test_img -o "refcount_bits=64" 64M
  71 print_refcount_bits
  72
  73 # 16 is the default
  74 _make_test_img 64M
  75 print_refcount_bits
  76
  77 echo
  78 echo '=== refcount_bits and compat=0.10 ==='
  79 echo
  80
  81 # Should work
  82 _make_test_img -o "compat=0.10,refcount_bits=16" 64M
  83 print_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
  90 echo
  91 echo '=== Snapshot limit on refcount_bits=1 ==='
  92 echo
  93
  94 _make_test_img -o "refcount_bits=1" 64M
  95 print_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
 106 echo
 107 echo '=== Snapshot limit on refcount_bits=2 ==='
 108 echo
 109
 110 _make_test_img -o "refcount_bits=2" 64M
 111 print_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
 124 echo
 125 echo '=== Compressed clusters with refcount_bits=1 ==='
 126 echo
 127
 128 _make_test_img -o "refcount_bits=1" 64M
 129 print_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
 140 echo
 141 echo '=== MSb set in 64 bit refcount ==='
 142 echo
 143
 144 _make_test_img -o "refcount_bits=64" 64M
 145 print_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
 150 poke_file "$TEST_IMG" $((0x20028)) "\x80\x00\x00\x00\x00\x00\x00\x00"
 151
 152 # Clear OFLAG_COPIED in the L2 entry of the data cluster
 153 poke_file "$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
 158 echo
 159 echo '=== Snapshot on maximum 64 bit refcount value ==='
 160 echo
 161
 162 _make_test_img -o "refcount_bits=64" 64M
 163 print_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
 168 poke_file "$TEST_IMG" $((0x20028)) "\xff\xff\xff\xff\xff\xff\xff\xff"
 169
 170 # Clear OFLAG_COPIED in the L2 entry of the data cluster
 171 poke_file "$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
 181 echo
 182 echo '=== Amend from refcount_bits=16 to refcount_bits=1 ==='
 183 echo
 184
 185 _make_test_img 64M
 186 print_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
 191 print_refcount_bits
 192
 193 echo
 194 echo '=== Amend from refcount_bits=1 to refcount_bits=64 ==='
 195 echo
 196
 197 $QEMU_IMG amend -o refcount_bits=64 "$TEST_IMG"
 198 _check_test_img
 199 print_refcount_bits
 200
 201 echo
 202 echo '=== Amend to compat=0.10 ==='
 203 echo
 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"
 207 print_refcount_bits
 208 # Should work
 209 $QEMU_IMG amend -o compat=0.10,refcount_bits=16 "$TEST_IMG"
 210 _check_test_img
 211 print_refcount_bits
 212
 213 # Get back to compat=1.1 and refcount_bits=16
 214 $QEMU_IMG amend -o compat=1.1 "$TEST_IMG"
 215 print_refcount_bits
 216 # Should not work
 217 $QEMU_IMG amend -o refcount_bits=32,compat=0.10 "$TEST_IMG"
 218 print_refcount_bits
 219
 220 echo
 221 echo '=== Amend with snapshot ==='
 222 echo
 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
 232 print_refcount_bits
 233
 234 # Should work
 235 $QEMU_IMG amend -o refcount_bits=2 "$TEST_IMG"
 236 _check_test_img
 237 print_refcount_bits
 238
 239 echo
 240 echo '=== Testing too many references for check ==='
 241 echo
 242
 243 _make_test_img -o "refcount_bits=1" 64M
 244 print_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
 250 poke_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"
 257 print_refcount_bits
 258
 259 # And try again
 260 _check_test_img -r all
 261
 262 echo
 263 echo '=== Multiple walks necessary during amend ==='
 264 echo
 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'
 286 print_refcount_bits
 287
 288 _check_test_img
 289
 290
 291 # success, all done
 292 echo '*** done'
 293 rm -f $seq.full
 294 status=0