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 _unsupported_imgopts refcount_bits 'compat=0.10'
  45
  46 print_refcount_bits()
  47 {
  48     $QEMU_IMG info "$TEST_IMG" | sed -n '/refcount bits:/ s/^ *//p'
  49 }
  50
  51 echo
  52 echo '=== refcount_bits limits ==='
  53 echo
  54
  55 # Must be positive (non-zero)
  56 IMGOPTS="$IMGOPTS,refcount_bits=0" _make_test_img 64M
  57 # Must be positive (non-negative)
  58 IMGOPTS="$IMGOPTS,refcount_bits=-1" _make_test_img 64M
  59 # May not exceed 64
  60 IMGOPTS="$IMGOPTS,refcount_bits=128" _make_test_img 64M
  61 # Must be a power of two
  62 IMGOPTS="$IMGOPTS,refcount_bits=42" _make_test_img 64M
  63
  64 # 1 is the minimum
  65 IMGOPTS="$IMGOPTS,refcount_bits=1" _make_test_img 64M
  66 print_refcount_bits
  67
  68 # 64 is the maximum
  69 IMGOPTS="$IMGOPTS,refcount_bits=64" _make_test_img 64M
  70 print_refcount_bits
  71
  72 # 16 is the default
  73 _make_test_img 64M
  74 print_refcount_bits
  75
  76 echo
  77 echo '=== refcount_bits and compat=0.10 ==='
  78 echo
  79
  80 # Should work
  81 IMGOPTS="$IMGOPTS,compat=0.10,refcount_bits=16" _make_test_img 64M
  82 print_refcount_bits
  83
  84 # Should not work
  85 IMGOPTS="$IMGOPTS,compat=0.10,refcount_bits=1" _make_test_img 64M
  86 IMGOPTS="$IMGOPTS,compat=0.10,refcount_bits=64" _make_test_img 64M
  87
  88
  89 echo
  90 echo '=== Snapshot limit on refcount_bits=1 ==='
  91 echo
  92
  93 IMGOPTS="$IMGOPTS,refcount_bits=1" _make_test_img 64M
  94 print_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
 105 echo
 106 echo '=== Snapshot limit on refcount_bits=2 ==='
 107 echo
 108
 109 IMGOPTS="$IMGOPTS,refcount_bits=2" _make_test_img 64M
 110 print_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
 123 echo
 124 echo '=== Compressed clusters with refcount_bits=1 ==='
 125 echo
 126
 127 IMGOPTS="$IMGOPTS,refcount_bits=1" _make_test_img 64M
 128 print_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
 139 echo
 140 echo '=== MSb set in 64 bit refcount ==='
 141 echo
 142
 143 IMGOPTS="$IMGOPTS,refcount_bits=64" _make_test_img 64M
 144 print_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
 149 poke_file "$TEST_IMG" $((0x20028)) "\x80\x00\x00\x00\x00\x00\x00\x00"
 150
 151 # Clear OFLAG_COPIED in the L2 entry of the data cluster
 152 poke_file "$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
 157 echo
 158 echo '=== Snapshot on maximum 64 bit refcount value ==='
 159 echo
 160
 161 IMGOPTS="$IMGOPTS,refcount_bits=64" _make_test_img 64M
 162 print_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
 167 poke_file "$TEST_IMG" $((0x20028)) "\xff\xff\xff\xff\xff\xff\xff\xff"
 168
 169 # Clear OFLAG_COPIED in the L2 entry of the data cluster
 170 poke_file "$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
 180 echo
 181 echo '=== Amend from refcount_bits=16 to refcount_bits=1 ==='
 182 echo
 183
 184 _make_test_img 64M
 185 print_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
 190 print_refcount_bits
 191
 192 echo
 193 echo '=== Amend from refcount_bits=1 to refcount_bits=64 ==='
 194 echo
 195
 196 $QEMU_IMG amend -o refcount_bits=64 "$TEST_IMG"
 197 _check_test_img
 198 print_refcount_bits
 199
 200 echo
 201 echo '=== Amend to compat=0.10 ==='
 202 echo
 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"
 206 print_refcount_bits
 207 # Should work
 208 $QEMU_IMG amend -o compat=0.10,refcount_bits=16 "$TEST_IMG"
 209 _check_test_img
 210 print_refcount_bits
 211
 212 # Get back to compat=1.1 and refcount_bits=16
 213 $QEMU_IMG amend -o compat=1.1 "$TEST_IMG"
 214 print_refcount_bits
 215 # Should not work
 216 $QEMU_IMG amend -o refcount_bits=32,compat=0.10 "$TEST_IMG"
 217 print_refcount_bits
 218
 219 echo
 220 echo '=== Amend with snapshot ==='
 221 echo
 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
 231 print_refcount_bits
 232
 233 # Should work
 234 $QEMU_IMG amend -o refcount_bits=2 "$TEST_IMG"
 235 _check_test_img
 236 print_refcount_bits
 237
 238 echo
 239 echo '=== Testing too many references for check ==='
 240 echo
 241
 242 IMGOPTS="$IMGOPTS,refcount_bits=1" _make_test_img 64M
 243 print_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
 249 poke_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"
 256 print_refcount_bits
 257
 258 # And try again
 259 _check_test_img -r all
 260
 261 echo
 262 echo '=== Multiple walks necessary during amend ==='
 263 echo
 264
 265 IMGOPTS="$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'
 285 print_refcount_bits
 286
 287 _check_test_img
 288
 289
 290 # success, all done
 291 echo '*** done'
 292 rm -f $seq.full
 293 status=0