tests/qemu-iotests/154

   1 #!/bin/bash
   2 #
   3 # qcow2 specific bdrv_pwrite_zeroes tests with backing files (complements 034)
   4 #
   5 # Copyright (C) 2016-2017 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=kwolf@redhat.com
  23
  24 seq=`basename $0`
  25 echo "QA output created by $seq"
  26
  27 status=1        # failure is the default!
  28
  29 _cleanup()
  30 {
  31         _cleanup_test_img
  32 }
  33 trap "_cleanup; exit \$status" 0 1 2 3 15
  34
  35 # get standard environment, filters and checks
  36 . ./common.rc
  37 . ./common.filter
  38
  39 _supported_fmt qcow2
  40 _supported_proto file
  41 _supported_os Linux
  42
  43 CLUSTER_SIZE=4k
  44 size=$((128 * 1024 * 1024))
  45
  46 # This test requires zero clusters, added in v3 images
  47 _unsupported_imgopts compat=0.10
  48
  49 echo
  50 echo == backing file contains zeros ==
  51
  52 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
  53 _make_test_img -b "$TEST_IMG.base"
  54
  55 # Make sure that the whole cluster is allocated even for partial write_zeroes
  56 # when the backing file contains zeros
  57
  58 # X = non-zero data sector in backing file
  59 # - = sector unallocated in whole backing chain
  60 # 0 = sector touched by write_zeroes request
  61
  62 # 1. Tail unaligned:    00 00 -- --
  63 # 2. Head unaligned:    -- -- 00 00
  64 # 3. Both unaligned:    -- 00 00 --
  65 # 4. Both, 2 clusters:  -- -- -- 00 | 00 -- -- --
  66
  67 $QEMU_IO -c "write -z 0 2k" "$TEST_IMG" | _filter_qemu_io
  68 $QEMU_IO -c "write -z 10k 2k" "$TEST_IMG" | _filter_qemu_io
  69 $QEMU_IO -c "write -z 17k 2k" "$TEST_IMG" | _filter_qemu_io
  70 $QEMU_IO -c "write -z 27k 2k" "$TEST_IMG" | _filter_qemu_io
  71 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
  72
  73 echo
  74 echo == backing file contains non-zero data before write_zeroes ==
  75
  76 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
  77 _make_test_img -b "$TEST_IMG.base"
  78
  79 # Single cluster; non-zero data at the cluster start
  80 # ... | XX -- 00 -- | ...
  81 $QEMU_IO -c "write -P 0x11 32k 1k" "$TEST_IMG.base" | _filter_qemu_io
  82 $QEMU_IO -c "write -z 34k 1k" "$TEST_IMG" | _filter_qemu_io
  83 $QEMU_IO -c "read -P 0x11 32k 1k" "$TEST_IMG" | _filter_qemu_io
  84 $QEMU_IO -c "read -P 0 33k 3k" "$TEST_IMG" | _filter_qemu_io
  85
  86 # Single cluster; non-zero data exists, but not at the cluster start
  87 # ... | -- XX 00 -- | ...
  88 $QEMU_IO -c "write -P 0x11 65k 1k" "$TEST_IMG.base" | _filter_qemu_io
  89 $QEMU_IO -c "write -z 66k 1k" "$TEST_IMG" | _filter_qemu_io
  90 $QEMU_IO -c "read -P 0x11 65k 1k" "$TEST_IMG" | _filter_qemu_io
  91 $QEMU_IO -c "read -P 0 64k 1k" "$TEST_IMG" | _filter_qemu_io
  92 $QEMU_IO -c "read -P 0 66k 2k" "$TEST_IMG" | _filter_qemu_io
  93
  94 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
  95
  96 echo
  97 echo == backing file contains non-zero data after write_zeroes ==
  98
  99 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 100 _make_test_img -b "$TEST_IMG.base"
 101
 102 # Single cluster; non-zero data directly after request
 103 # ... | -- 00 XX -- | ...
 104 $QEMU_IO -c "write -P 0x11 34k 1k" "$TEST_IMG.base" | _filter_qemu_io
 105 $QEMU_IO -c "write -z 33k 1k" "$TEST_IMG" | _filter_qemu_io
 106 $QEMU_IO -c "read -P 0 32k 2k" "$TEST_IMG" | _filter_qemu_io
 107 $QEMU_IO -c "read -P 0x11 34k 1k" "$TEST_IMG" | _filter_qemu_io
 108 $QEMU_IO -c "read -P 0 35k 1k" "$TEST_IMG" | _filter_qemu_io
 109
 110 # Single cluster; non-zero data exists, but not directly after request
 111 # ... | -- 00 -- XX | ...
 112 $QEMU_IO -c "write -P 0x11 43k 1k" "$TEST_IMG.base" | _filter_qemu_io
 113 $QEMU_IO -c "write -z 41k 1k" "$TEST_IMG" | _filter_qemu_io
 114 $QEMU_IO -c "read -P 0x11 43k 1k" "$TEST_IMG" | _filter_qemu_io
 115 $QEMU_IO -c "read -P 0 40k 3k" "$TEST_IMG" | _filter_qemu_io
 116
 117 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 118
 119 echo
 120 echo == write_zeroes covers non-zero data ==
 121
 122 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 123 _make_test_img -b "$TEST_IMG.base"
 124
 125 # non-zero data at front of request
 126 # Backing file: -- XX -- --
 127 # Active layer: -- 00 00 --
 128
 129 $QEMU_IO -c "write -P 0x11 5k 1k" "$TEST_IMG.base" | _filter_qemu_io
 130 $QEMU_IO -c "write -z 5k 2k" "$TEST_IMG" | _filter_qemu_io
 131 $QEMU_IO -c "read -P 0 4k 4k" "$TEST_IMG" | _filter_qemu_io
 132
 133 # non-zero data at end of request
 134 # Backing file: -- -- XX --
 135 # Active layer: -- 00 00 --
 136
 137 $QEMU_IO -c "write -P 0x11 14k 1k" "$TEST_IMG.base" | _filter_qemu_io
 138 $QEMU_IO -c "write -z 13k 2k" "$TEST_IMG" | _filter_qemu_io
 139 $QEMU_IO -c "read -P 0 12k 4k" "$TEST_IMG" | _filter_qemu_io
 140
 141 # non-zero data matches size of request
 142 # Backing file: -- XX XX --
 143 # Active layer: -- 00 00 --
 144
 145 $QEMU_IO -c "write -P 0x11 21k 2k" "$TEST_IMG.base" | _filter_qemu_io
 146 $QEMU_IO -c "write -z 21k 2k" "$TEST_IMG" | _filter_qemu_io
 147 $QEMU_IO -c "read -P 0 20k 4k" "$TEST_IMG" | _filter_qemu_io
 148
 149 # non-zero data smaller than request
 150 # Backing file: -- -X X- --
 151 # Active layer: -- 00 00 --
 152
 153 $QEMU_IO -c "write -P 0x11 30208 1k" "$TEST_IMG.base" | _filter_qemu_io
 154 $QEMU_IO -c "write -z 29k 2k" "$TEST_IMG" | _filter_qemu_io
 155 $QEMU_IO -c "read -P 0 28k 4k" "$TEST_IMG" | _filter_qemu_io
 156
 157 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 158
 159 echo
 160 echo == spanning two clusters, non-zero before request ==
 161
 162 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 163 _make_test_img -b "$TEST_IMG.base"
 164
 165 # Two clusters; non-zero data before request:
 166 # 1. At cluster start:          32k: XX -- -- 00 | 00 -- -- --
 167 # 2. Between unallocated space: 48k: -- XX -- 00 | 00 -- -- --
 168 # 3. Directly before request:   64k: -- -- XX 00 | 00 -- -- --
 169
 170 $QEMU_IO -c "write -P 0x11 32k 1k" "$TEST_IMG.base" | _filter_qemu_io
 171 $QEMU_IO -c "write -z 35k 2k" "$TEST_IMG" | _filter_qemu_io
 172 $QEMU_IO -c "read -P 0x11 32k 1k" "$TEST_IMG" | _filter_qemu_io
 173 $QEMU_IO -c "read -P 0 33k 7k" "$TEST_IMG" | _filter_qemu_io
 174
 175 $QEMU_IO -c "write -P 0x11 49k 1k" "$TEST_IMG.base" | _filter_qemu_io
 176 $QEMU_IO -c "write -z 51k 2k" "$TEST_IMG" | _filter_qemu_io
 177 $QEMU_IO -c "read -P 0 48k 1k" "$TEST_IMG" | _filter_qemu_io
 178 $QEMU_IO -c "read -P 0x11 49k 1k" "$TEST_IMG" | _filter_qemu_io
 179 $QEMU_IO -c "read -P 0 50k 6k" "$TEST_IMG" | _filter_qemu_io
 180
 181 $QEMU_IO -c "write -P 0x11 66k 1k" "$TEST_IMG.base" | _filter_qemu_io
 182 $QEMU_IO -c "write -z 67k 2k" "$TEST_IMG" | _filter_qemu_io
 183 $QEMU_IO -c "read -P 0 64k 2k" "$TEST_IMG" | _filter_qemu_io
 184 $QEMU_IO -c "read -P 0x11 66k 1k" "$TEST_IMG" | _filter_qemu_io
 185 $QEMU_IO -c "read -P 0 67k 5k" "$TEST_IMG" | _filter_qemu_io
 186
 187 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 188
 189 echo
 190 echo == spanning two clusters, non-zero after request ==
 191
 192 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 193 _make_test_img -b "$TEST_IMG.base"
 194
 195 # Two clusters; non-zero data after request:
 196 # 1. Directly after request:    32k: -- -- -- 00 | 00 XX -- --
 197 # 2. Between unallocated space: 48k: -- -- -- 00 | 00 -- XX --
 198 # 3. At cluster end:            64k: -- -- -- 00 | 00 -- -- XX
 199
 200 $QEMU_IO -c "write -P 0x11 37k 1k" "$TEST_IMG.base" | _filter_qemu_io
 201 $QEMU_IO -c "write -z 35k 2k" "$TEST_IMG" | _filter_qemu_io
 202 $QEMU_IO -c "read -P 0 32k 5k" "$TEST_IMG" | _filter_qemu_io
 203 $QEMU_IO -c "read -P 0x11 37k 1k" "$TEST_IMG" | _filter_qemu_io
 204 $QEMU_IO -c "read -P 0 38k 2k" "$TEST_IMG" | _filter_qemu_io
 205
 206 $QEMU_IO -c "write -P 0x11 54k 1k" "$TEST_IMG.base" | _filter_qemu_io
 207 $QEMU_IO -c "write -z 51k 2k" "$TEST_IMG" | _filter_qemu_io
 208 $QEMU_IO -c "read -P 0 48k 6k" "$TEST_IMG" | _filter_qemu_io
 209 $QEMU_IO -c "read -P 0x11 54k 1k" "$TEST_IMG" | _filter_qemu_io
 210 $QEMU_IO -c "read -P 0 55k 1k" "$TEST_IMG" | _filter_qemu_io
 211
 212 $QEMU_IO -c "write -P 0x11 71k 1k" "$TEST_IMG.base" | _filter_qemu_io
 213 $QEMU_IO -c "write -z 67k 2k" "$TEST_IMG" | _filter_qemu_io
 214 $QEMU_IO -c "read -P 0 64k 7k" "$TEST_IMG" | _filter_qemu_io
 215 $QEMU_IO -c "read -P 0x11 71k 1k" "$TEST_IMG" | _filter_qemu_io
 216
 217 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 218
 219 echo
 220 echo == spanning two clusters, partially overwriting backing file ==
 221
 222 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 223 _make_test_img -b "$TEST_IMG.base"
 224
 225 # Backing file: -- -- XX XX | XX XX -- --
 226 # Active layer: -- -- XX 00 | 00 XX -- --
 227
 228 $QEMU_IO -c "write -P 0x11 2k 4k" "$TEST_IMG.base" | _filter_qemu_io
 229 $QEMU_IO -c "write -z 3k 2k" "$TEST_IMG" | _filter_qemu_io
 230 $QEMU_IO -c "read -P 0 0k 2k" "$TEST_IMG" | _filter_qemu_io
 231 $QEMU_IO -c "read -P 0x11 2k 1k" "$TEST_IMG" | _filter_qemu_io
 232 $QEMU_IO -c "read -P 0 3k 2k" "$TEST_IMG" | _filter_qemu_io
 233 $QEMU_IO -c "read -P 0x11 5k 1k" "$TEST_IMG" | _filter_qemu_io
 234 $QEMU_IO -c "read -P 0 6k 2k" "$TEST_IMG" | _filter_qemu_io
 235
 236 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 237
 238 echo
 239 echo == spanning multiple clusters, non-zero in first cluster ==
 240
 241 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 242 _make_test_img -b "$TEST_IMG.base"
 243
 244 # Backing file: 64k: XX XX -- -- | -- -- -- -- | -- -- -- --
 245 # Active layer: 64k: XX XX 00 00 | 00 00 00 00 | 00 -- -- --
 246
 247 $QEMU_IO -c "write -P 0x11 64k 2k" "$TEST_IMG.base" | _filter_qemu_io
 248 $QEMU_IO -c "write -z 66k 7k" "$TEST_IMG" | _filter_qemu_io
 249 $QEMU_IO -c "read -P 0x11 64k 2k" "$TEST_IMG" | _filter_qemu_io
 250 $QEMU_IO -c "read -P 0 66k 10k" "$TEST_IMG" | _filter_qemu_io
 251
 252 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 253
 254 echo
 255 echo == spanning multiple clusters, non-zero in intermediate cluster ==
 256
 257 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 258 _make_test_img -b "$TEST_IMG.base"
 259
 260 # Backing file: 64k: -- -- -- -- | -- XX XX -- | -- -- -- --
 261 # Active layer: 64k: -- -- 00 00 | 00 00 00 00 | 00 -- -- --
 262
 263 $QEMU_IO -c "write -P 0x11 69k 2k" "$TEST_IMG.base" | _filter_qemu_io
 264 $QEMU_IO -c "write -z 66k 7k" "$TEST_IMG" | _filter_qemu_io
 265 $QEMU_IO -c "read -P 0 64k 12k" "$TEST_IMG" | _filter_qemu_io
 266
 267 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 268
 269 echo
 270 echo == spanning multiple clusters, non-zero in final cluster ==
 271
 272 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 273 _make_test_img -b "$TEST_IMG.base"
 274
 275 # Backing file: 64k: -- -- -- -- | -- -- -- -- | -- -- XX XX
 276 # Active layer: 64k: -- -- 00 00 | 00 00 00 00 | 00 -- XX XX
 277
 278 $QEMU_IO -c "write -P 0x11 74k 2k" "$TEST_IMG.base" | _filter_qemu_io
 279 $QEMU_IO -c "write -z 66k 7k" "$TEST_IMG" | _filter_qemu_io
 280 $QEMU_IO -c "read -P 0 64k 10k" "$TEST_IMG" | _filter_qemu_io
 281 $QEMU_IO -c "read -P 0x11 74k 2k" "$TEST_IMG" | _filter_qemu_io
 282
 283 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 284
 285 echo
 286 echo == spanning multiple clusters, partially overwriting backing file ==
 287
 288 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 289 _make_test_img -b "$TEST_IMG.base"
 290
 291 # Backing file: 64k: -- XX XX XX | XX XX XX XX | XX XX XX --
 292 # Active layer: 64k: -- XX 00 00 | 00 00 00 00 | 00 XX XX --
 293
 294 $QEMU_IO -c "write -P 0x11 65k 10k" "$TEST_IMG.base" | _filter_qemu_io
 295 $QEMU_IO -c "write -z 66k 7k" "$TEST_IMG" | _filter_qemu_io
 296 $QEMU_IO -c "read -P 0 64k 1k" "$TEST_IMG" | _filter_qemu_io
 297 $QEMU_IO -c "read -P 0x11 65k 1k" "$TEST_IMG" | _filter_qemu_io
 298 $QEMU_IO -c "read -P 0 66k 7k" "$TEST_IMG" | _filter_qemu_io
 299 $QEMU_IO -c "read -P 0x11 73k 2k" "$TEST_IMG" | _filter_qemu_io
 300 $QEMU_IO -c "read -P 0 75k 1k" "$TEST_IMG" | _filter_qemu_io
 301
 302 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 303
 304 echo
 305 echo == unaligned image tail cluster, no allocation needed ==
 306
 307 # With no backing file, write to all or part of unallocated partial cluster
 308 # will mark the cluster as zero, but does not allocate.
 309 # Re-create the image each time to get back to unallocated clusters.
 310
 311 # Write at the front: sector-wise, the request is: 128m... | 00 -- -- --
 312 _make_test_img $((size + 2048))
 313 $QEMU_IO -c "write -z $size 512" "$TEST_IMG" | _filter_qemu_io
 314 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 315 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 316
 317 # Write at the back: sector-wise, the request is: 128m... | -- -- -- 00
 318 _make_test_img $((size + 2048))
 319 $QEMU_IO -c "write -z $((size + 1536)) 512" "$TEST_IMG" | _filter_qemu_io
 320 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 321 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 322
 323 # Write at middle: sector-wise, the request is: 128m... | -- 00 00 --
 324 _make_test_img $((size + 2048))
 325 $QEMU_IO -c "write -z $((size + 512)) 1024" "$TEST_IMG" | _filter_qemu_io
 326 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 327 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 328
 329 # Write entire cluster: sector-wise, the request is: 128m... | 00 00 00 00
 330 _make_test_img $((size + 2048))
 331 $QEMU_IO -c "write -z $size 2048" "$TEST_IMG" | _filter_qemu_io
 332 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 333 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 334
 335 # Repeat with backing file holding unallocated cluster.
 336 CLUSTER_SIZE=2048 TEST_IMG="$TEST_IMG.base" _make_test_img $((size + 1024))
 337
 338 # Write at the front: sector-wise, the request is:
 339 # backing: 128m... | -- --
 340 # active:  128m... | 00 -- -- --
 341 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 342 $QEMU_IO -c "write -z $size 512" "$TEST_IMG" | _filter_qemu_io
 343 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 344 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 345
 346 # Write at the back: sector-wise, the request is:
 347 # backing: 128m... | -- --
 348 # active:  128m... | -- -- -- 00
 349 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 350 $QEMU_IO -c "write -z $((size + 1536)) 512" "$TEST_IMG" | _filter_qemu_io
 351 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 352 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 353
 354 # Write at middle: sector-wise, the request is:
 355 # backing: 128m... | -- --
 356 # active:  128m... | -- 00 00 --
 357 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 358 $QEMU_IO -c "write -z $((size + 512)) 1024" "$TEST_IMG" | _filter_qemu_io
 359 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 360 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 361
 362 # Write entire cluster: sector-wise, the request is:
 363 # backing: 128m... | -- --
 364 # active:  128m... | 00 00 00 00
 365 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 366 $QEMU_IO -c "write -z $size 2048" "$TEST_IMG" | _filter_qemu_io
 367 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 368 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 369
 370 # Repeat with backing file holding zero'd cluster
 371 $QEMU_IO -c "write -z $size 512" "$TEST_IMG.base" | _filter_qemu_io
 372
 373 # Write at the front: sector-wise, the request is:
 374 # backing: 128m... | 00 00
 375 # active:  128m... | 00 -- -- --
 376 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 377 $QEMU_IO -c "write -z $size 512" "$TEST_IMG" | _filter_qemu_io
 378 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 379 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 380
 381 # Write at the back: sector-wise, the request is:
 382 # backing: 128m... | 00 00
 383 # active:  128m... | -- -- -- 00
 384 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 385 $QEMU_IO -c "write -z $((size + 1536)) 512" "$TEST_IMG" | _filter_qemu_io
 386 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 387 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 388
 389 # Write at middle: sector-wise, the request is:
 390 # backing: 128m... | 00 00
 391 # active:  128m... | -- 00 00 --
 392 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 393 $QEMU_IO -c "write -z $((size + 512)) 1024" "$TEST_IMG" | _filter_qemu_io
 394 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 395 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 396
 397 # Write entire cluster: sector-wise, the request is:
 398 # backing: 128m... | 00 00
 399 # active:  128m... | 00 00 00 00
 400 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 401 $QEMU_IO -c "write -z $size 2048" "$TEST_IMG" | _filter_qemu_io
 402 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 403 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 404
 405 # A preallocated cluster maintains its allocation, whether it stays as
 406 # data due to a partial write:
 407 # Convert 128m... | XX XX => ... | XX 00
 408 _make_test_img $((size + 1024))
 409 $QEMU_IO -c "write -P 1 $((size)) 1024" "$TEST_IMG" | _filter_qemu_io
 410 $QEMU_IO -c "write -z $((size + 512)) 512" "$TEST_IMG" | _filter_qemu_io
 411 $QEMU_IO -c "read -P 1 $((size)) 512" "$TEST_IMG" | _filter_qemu_io
 412 $QEMU_IO -c "read -P 0 $((size + 512)) 512" "$TEST_IMG" | _filter_qemu_io
 413 $QEMU_IO -c "alloc $size 1024" "$TEST_IMG" | _filter_qemu_io
 414 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 415
 416 # or because it is the entire cluster and can use the zero flag:
 417 # Convert 128m... | XX XX => ... | 00 00
 418 $QEMU_IO -c "write -z $((size)) 1024" "$TEST_IMG" | _filter_qemu_io
 419 $QEMU_IO -c "alloc $size 1024" "$TEST_IMG" | _filter_qemu_io
 420 $QEMU_IO -c "read -P 0 $size 1024" "$TEST_IMG" | _filter_qemu_io
 421 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 422
 423 echo
 424 echo == unaligned image tail cluster, allocation required ==
 425
 426 # Write beyond backing file must COW
 427 # Backing file: 128m... | XX --
 428 # Active layer: 128m... | -- -- 00 --
 429 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $((size + 1024))
 430 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 431 $QEMU_IO -c "write -P 1 $((size)) 512" "$TEST_IMG.base" | _filter_qemu_io
 432 $QEMU_IO -c "write -z $((size + 1024)) 512" "$TEST_IMG" | _filter_qemu_io
 433 $QEMU_IO -c "read -P 1 $((size)) 512" "$TEST_IMG" | _filter_qemu_io
 434 $QEMU_IO -c "read -P 0 $((size + 512)) 1536" "$TEST_IMG" | _filter_qemu_io
 435 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 436
 437 # Writes at boundaries of (partial) cluster must not lose mid-cluster data
 438 # Backing file: 128m: ... | -- XX
 439 # Active layer: 128m: ... | 00 -- -- 00
 440 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $((size + 1024))
 441 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 442 $QEMU_IO -c "write -P 1 $((size + 512)) 512" "$TEST_IMG.base" | _filter_qemu_io
 443 $QEMU_IO -c "write -z $((size)) 512" "$TEST_IMG" | _filter_qemu_io
 444 $QEMU_IO -c "read -P 0 $((size)) 512" "$TEST_IMG" | _filter_qemu_io
 445 $QEMU_IO -c "read -P 1 $((size + 512)) 512" "$TEST_IMG" | _filter_qemu_io
 446 $QEMU_IO -c "read -P 0 $((size + 1024)) 1024" "$TEST_IMG" | _filter_qemu_io
 447 $QEMU_IO -c "write -z $((size + 1536)) 512" "$TEST_IMG" | _filter_qemu_io
 448 $QEMU_IO -c "read -P 0 $((size)) 512" "$TEST_IMG" | _filter_qemu_io
 449 $QEMU_IO -c "read -P 1 $((size + 512)) 512" "$TEST_IMG" | _filter_qemu_io
 450 $QEMU_IO -c "read -P 0 $((size + 1024)) 1024" "$TEST_IMG" | _filter_qemu_io
 451 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 452
 453 # success, all done
 454 echo "*** done"
 455 rm -f $seq.full
 456 status=0