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 $seq"
  26
  27 here=`pwd`
  28 status=1        # failure is the default!
  29
  30 _cleanup()
  31 {
  32         _cleanup_test_img
  33 }
  34 trap "_cleanup; exit \$status" 0 1 2 3 15
  35
  36 # get standard environment, filters and checks
  37 . ./common.rc
  38 . ./common.filter
  39
  40 _supported_fmt qcow2
  41 _supported_proto file
  42 _supported_os Linux
  43
  44 CLUSTER_SIZE=4k
  45 size=$((128 * 1024 * 1024))
  46
  47 # This test requires zero clusters, added in v3 images
  48 _unsupported_imgopts compat=0.10
  49
  50 echo
  51 echo == backing file contains zeros ==
  52
  53 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
  54 _make_test_img -b "$TEST_IMG.base"
  55
  56 # Make sure that the whole cluster is allocated even for partial write_zeroes
  57 # when the backing file contains zeros
  58
  59 # X = non-zero data sector in backing file
  60 # - = sector unallocated in whole backing chain
  61 # 0 = sector touched by write_zeroes request
  62
  63 # 1. Tail unaligned:    00 00 -- --
  64 # 2. Head unaligned:    -- -- 00 00
  65 # 3. Both unaligned:    -- 00 00 --
  66 # 4. Both, 2 clusters:  -- -- -- 00 | 00 -- -- --
  67
  68 $QEMU_IO -c "write -z 0 2k" "$TEST_IMG" | _filter_qemu_io
  69 $QEMU_IO -c "write -z 10k 2k" "$TEST_IMG" | _filter_qemu_io
  70 $QEMU_IO -c "write -z 17k 2k" "$TEST_IMG" | _filter_qemu_io
  71 $QEMU_IO -c "write -z 27k 2k" "$TEST_IMG" | _filter_qemu_io
  72 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
  73
  74 echo
  75 echo == backing file contains non-zero data before write_zeroes ==
  76
  77 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
  78 _make_test_img -b "$TEST_IMG.base"
  79
  80 # Single cluster; non-zero data at the cluster start
  81 # ... | XX -- 00 -- | ...
  82 $QEMU_IO -c "write -P 0x11 32k 1k" "$TEST_IMG.base" | _filter_qemu_io
  83 $QEMU_IO -c "write -z 34k 1k" "$TEST_IMG" | _filter_qemu_io
  84 $QEMU_IO -c "read -P 0x11 32k 1k" "$TEST_IMG" | _filter_qemu_io
  85 $QEMU_IO -c "read -P 0 33k 3k" "$TEST_IMG" | _filter_qemu_io
  86
  87 # Single cluster; non-zero data exists, but not at the cluster start
  88 # ... | -- XX 00 -- | ...
  89 $QEMU_IO -c "write -P 0x11 65k 1k" "$TEST_IMG.base" | _filter_qemu_io
  90 $QEMU_IO -c "write -z 66k 1k" "$TEST_IMG" | _filter_qemu_io
  91 $QEMU_IO -c "read -P 0x11 65k 1k" "$TEST_IMG" | _filter_qemu_io
  92 $QEMU_IO -c "read -P 0 64k 1k" "$TEST_IMG" | _filter_qemu_io
  93 $QEMU_IO -c "read -P 0 66k 2k" "$TEST_IMG" | _filter_qemu_io
  94
  95 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
  96
  97 echo
  98 echo == backing file contains non-zero data after write_zeroes ==
  99
 100 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 101 _make_test_img -b "$TEST_IMG.base"
 102
 103 # Single cluster; non-zero data directly after request
 104 # ... | -- 00 XX -- | ...
 105 $QEMU_IO -c "write -P 0x11 34k 1k" "$TEST_IMG.base" | _filter_qemu_io
 106 $QEMU_IO -c "write -z 33k 1k" "$TEST_IMG" | _filter_qemu_io
 107 $QEMU_IO -c "read -P 0 32k 2k" "$TEST_IMG" | _filter_qemu_io
 108 $QEMU_IO -c "read -P 0x11 34k 1k" "$TEST_IMG" | _filter_qemu_io
 109 $QEMU_IO -c "read -P 0 35k 1k" "$TEST_IMG" | _filter_qemu_io
 110
 111 # Single cluster; non-zero data exists, but not directly after request
 112 # ... | -- 00 -- XX | ...
 113 $QEMU_IO -c "write -P 0x11 43k 1k" "$TEST_IMG.base" | _filter_qemu_io
 114 $QEMU_IO -c "write -z 41k 1k" "$TEST_IMG" | _filter_qemu_io
 115 $QEMU_IO -c "read -P 0x11 43k 1k" "$TEST_IMG" | _filter_qemu_io
 116 $QEMU_IO -c "read -P 0 40k 3k" "$TEST_IMG" | _filter_qemu_io
 117
 118 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 119
 120 echo
 121 echo == write_zeroes covers non-zero data ==
 122
 123 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 124 _make_test_img -b "$TEST_IMG.base"
 125
 126 # non-zero data at front of request
 127 # Backing file: -- XX -- --
 128 # Active layer: -- 00 00 --
 129
 130 $QEMU_IO -c "write -P 0x11 5k 1k" "$TEST_IMG.base" | _filter_qemu_io
 131 $QEMU_IO -c "write -z 5k 2k" "$TEST_IMG" | _filter_qemu_io
 132 $QEMU_IO -c "read -P 0 4k 4k" "$TEST_IMG" | _filter_qemu_io
 133
 134 # non-zero data at end of request
 135 # Backing file: -- -- XX --
 136 # Active layer: -- 00 00 --
 137
 138 $QEMU_IO -c "write -P 0x11 14k 1k" "$TEST_IMG.base" | _filter_qemu_io
 139 $QEMU_IO -c "write -z 13k 2k" "$TEST_IMG" | _filter_qemu_io
 140 $QEMU_IO -c "read -P 0 12k 4k" "$TEST_IMG" | _filter_qemu_io
 141
 142 # non-zero data matches size of request
 143 # Backing file: -- XX XX --
 144 # Active layer: -- 00 00 --
 145
 146 $QEMU_IO -c "write -P 0x11 21k 2k" "$TEST_IMG.base" | _filter_qemu_io
 147 $QEMU_IO -c "write -z 21k 2k" "$TEST_IMG" | _filter_qemu_io
 148 $QEMU_IO -c "read -P 0 20k 4k" "$TEST_IMG" | _filter_qemu_io
 149
 150 # non-zero data smaller than request
 151 # Backing file: -- -X X- --
 152 # Active layer: -- 00 00 --
 153
 154 $QEMU_IO -c "write -P 0x11 30208 1k" "$TEST_IMG.base" | _filter_qemu_io
 155 $QEMU_IO -c "write -z 29k 2k" "$TEST_IMG" | _filter_qemu_io
 156 $QEMU_IO -c "read -P 0 28k 4k" "$TEST_IMG" | _filter_qemu_io
 157
 158 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 159
 160 echo
 161 echo == spanning two clusters, non-zero before request ==
 162
 163 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 164 _make_test_img -b "$TEST_IMG.base"
 165
 166 # Two clusters; non-zero data before request:
 167 # 1. At cluster start:          32k: XX -- -- 00 | 00 -- -- --
 168 # 2. Between unallocated space: 48k: -- XX -- 00 | 00 -- -- --
 169 # 3. Directly before request:   64k: -- -- XX 00 | 00 -- -- --
 170
 171 $QEMU_IO -c "write -P 0x11 32k 1k" "$TEST_IMG.base" | _filter_qemu_io
 172 $QEMU_IO -c "write -z 35k 2k" "$TEST_IMG" | _filter_qemu_io
 173 $QEMU_IO -c "read -P 0x11 32k 1k" "$TEST_IMG" | _filter_qemu_io
 174 $QEMU_IO -c "read -P 0 33k 7k" "$TEST_IMG" | _filter_qemu_io
 175
 176 $QEMU_IO -c "write -P 0x11 49k 1k" "$TEST_IMG.base" | _filter_qemu_io
 177 $QEMU_IO -c "write -z 51k 2k" "$TEST_IMG" | _filter_qemu_io
 178 $QEMU_IO -c "read -P 0 48k 1k" "$TEST_IMG" | _filter_qemu_io
 179 $QEMU_IO -c "read -P 0x11 49k 1k" "$TEST_IMG" | _filter_qemu_io
 180 $QEMU_IO -c "read -P 0 50k 6k" "$TEST_IMG" | _filter_qemu_io
 181
 182 $QEMU_IO -c "write -P 0x11 66k 1k" "$TEST_IMG.base" | _filter_qemu_io
 183 $QEMU_IO -c "write -z 67k 2k" "$TEST_IMG" | _filter_qemu_io
 184 $QEMU_IO -c "read -P 0 64k 2k" "$TEST_IMG" | _filter_qemu_io
 185 $QEMU_IO -c "read -P 0x11 66k 1k" "$TEST_IMG" | _filter_qemu_io
 186 $QEMU_IO -c "read -P 0 67k 5k" "$TEST_IMG" | _filter_qemu_io
 187
 188 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 189
 190 echo
 191 echo == spanning two clusters, non-zero after request ==
 192
 193 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 194 _make_test_img -b "$TEST_IMG.base"
 195
 196 # Two clusters; non-zero data after request:
 197 # 1. Directly after request:    32k: -- -- -- 00 | 00 XX -- --
 198 # 2. Between unallocated space: 48k: -- -- -- 00 | 00 -- XX --
 199 # 3. At cluster end:            64k: -- -- -- 00 | 00 -- -- XX
 200
 201 $QEMU_IO -c "write -P 0x11 37k 1k" "$TEST_IMG.base" | _filter_qemu_io
 202 $QEMU_IO -c "write -z 35k 2k" "$TEST_IMG" | _filter_qemu_io
 203 $QEMU_IO -c "read -P 0 32k 5k" "$TEST_IMG" | _filter_qemu_io
 204 $QEMU_IO -c "read -P 0x11 37k 1k" "$TEST_IMG" | _filter_qemu_io
 205 $QEMU_IO -c "read -P 0 38k 2k" "$TEST_IMG" | _filter_qemu_io
 206
 207 $QEMU_IO -c "write -P 0x11 54k 1k" "$TEST_IMG.base" | _filter_qemu_io
 208 $QEMU_IO -c "write -z 51k 2k" "$TEST_IMG" | _filter_qemu_io
 209 $QEMU_IO -c "read -P 0 48k 6k" "$TEST_IMG" | _filter_qemu_io
 210 $QEMU_IO -c "read -P 0x11 54k 1k" "$TEST_IMG" | _filter_qemu_io
 211 $QEMU_IO -c "read -P 0 55k 1k" "$TEST_IMG" | _filter_qemu_io
 212
 213 $QEMU_IO -c "write -P 0x11 71k 1k" "$TEST_IMG.base" | _filter_qemu_io
 214 $QEMU_IO -c "write -z 67k 2k" "$TEST_IMG" | _filter_qemu_io
 215 $QEMU_IO -c "read -P 0 64k 7k" "$TEST_IMG" | _filter_qemu_io
 216 $QEMU_IO -c "read -P 0x11 71k 1k" "$TEST_IMG" | _filter_qemu_io
 217
 218 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 219
 220 echo
 221 echo == spanning two clusters, partially overwriting backing file ==
 222
 223 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 224 _make_test_img -b "$TEST_IMG.base"
 225
 226 # Backing file: -- -- XX XX | XX XX -- --
 227 # Active layer: -- -- XX 00 | 00 XX -- --
 228
 229 $QEMU_IO -c "write -P 0x11 2k 4k" "$TEST_IMG.base" | _filter_qemu_io
 230 $QEMU_IO -c "write -z 3k 2k" "$TEST_IMG" | _filter_qemu_io
 231 $QEMU_IO -c "read -P 0 0k 2k" "$TEST_IMG" | _filter_qemu_io
 232 $QEMU_IO -c "read -P 0x11 2k 1k" "$TEST_IMG" | _filter_qemu_io
 233 $QEMU_IO -c "read -P 0 3k 2k" "$TEST_IMG" | _filter_qemu_io
 234 $QEMU_IO -c "read -P 0x11 5k 1k" "$TEST_IMG" | _filter_qemu_io
 235 $QEMU_IO -c "read -P 0 6k 2k" "$TEST_IMG" | _filter_qemu_io
 236
 237 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 238
 239 echo
 240 echo == spanning multiple clusters, non-zero in first cluster ==
 241
 242 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 243 _make_test_img -b "$TEST_IMG.base"
 244
 245 # Backing file: 64k: XX XX -- -- | -- -- -- -- | -- -- -- --
 246 # Active layer: 64k: XX XX 00 00 | 00 00 00 00 | 00 -- -- --
 247
 248 $QEMU_IO -c "write -P 0x11 64k 2k" "$TEST_IMG.base" | _filter_qemu_io
 249 $QEMU_IO -c "write -z 66k 7k" "$TEST_IMG" | _filter_qemu_io
 250 $QEMU_IO -c "read -P 0x11 64k 2k" "$TEST_IMG" | _filter_qemu_io
 251 $QEMU_IO -c "read -P 0 66k 10k" "$TEST_IMG" | _filter_qemu_io
 252
 253 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 254
 255 echo
 256 echo == spanning multiple clusters, non-zero in intermediate cluster ==
 257
 258 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 259 _make_test_img -b "$TEST_IMG.base"
 260
 261 # Backing file: 64k: -- -- -- -- | -- XX XX -- | -- -- -- --
 262 # Active layer: 64k: -- -- 00 00 | 00 00 00 00 | 00 -- -- --
 263
 264 $QEMU_IO -c "write -P 0x11 69k 2k" "$TEST_IMG.base" | _filter_qemu_io
 265 $QEMU_IO -c "write -z 66k 7k" "$TEST_IMG" | _filter_qemu_io
 266 $QEMU_IO -c "read -P 0 64k 12k" "$TEST_IMG" | _filter_qemu_io
 267
 268 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 269
 270 echo
 271 echo == spanning multiple clusters, non-zero in final cluster ==
 272
 273 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 274 _make_test_img -b "$TEST_IMG.base"
 275
 276 # Backing file: 64k: -- -- -- -- | -- -- -- -- | -- -- XX XX
 277 # Active layer: 64k: -- -- 00 00 | 00 00 00 00 | 00 -- XX XX
 278
 279 $QEMU_IO -c "write -P 0x11 74k 2k" "$TEST_IMG.base" | _filter_qemu_io
 280 $QEMU_IO -c "write -z 66k 7k" "$TEST_IMG" | _filter_qemu_io
 281 $QEMU_IO -c "read -P 0 64k 10k" "$TEST_IMG" | _filter_qemu_io
 282 $QEMU_IO -c "read -P 0x11 74k 2k" "$TEST_IMG" | _filter_qemu_io
 283
 284 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 285
 286 echo
 287 echo == spanning multiple clusters, partially overwriting backing file ==
 288
 289 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $size
 290 _make_test_img -b "$TEST_IMG.base"
 291
 292 # Backing file: 64k: -- XX XX XX | XX XX XX XX | XX XX XX --
 293 # Active layer: 64k: -- XX 00 00 | 00 00 00 00 | 00 XX XX --
 294
 295 $QEMU_IO -c "write -P 0x11 65k 10k" "$TEST_IMG.base" | _filter_qemu_io
 296 $QEMU_IO -c "write -z 66k 7k" "$TEST_IMG" | _filter_qemu_io
 297 $QEMU_IO -c "read -P 0 64k 1k" "$TEST_IMG" | _filter_qemu_io
 298 $QEMU_IO -c "read -P 0x11 65k 1k" "$TEST_IMG" | _filter_qemu_io
 299 $QEMU_IO -c "read -P 0 66k 7k" "$TEST_IMG" | _filter_qemu_io
 300 $QEMU_IO -c "read -P 0x11 73k 2k" "$TEST_IMG" | _filter_qemu_io
 301 $QEMU_IO -c "read -P 0 75k 1k" "$TEST_IMG" | _filter_qemu_io
 302
 303 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 304
 305 echo
 306 echo == unaligned image tail cluster, no allocation needed ==
 307
 308 # With no backing file, write to all or part of unallocated partial cluster
 309 # will mark the cluster as zero, but does not allocate.
 310 # Re-create the image each time to get back to unallocated clusters.
 311
 312 # Write at the front: sector-wise, the request is: 128m... | 00 -- -- --
 313 _make_test_img $((size + 2048))
 314 $QEMU_IO -c "write -z $size 512" "$TEST_IMG" | _filter_qemu_io
 315 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 316 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 317
 318 # Write at the back: sector-wise, the request is: 128m... | -- -- -- 00
 319 _make_test_img $((size + 2048))
 320 $QEMU_IO -c "write -z $((size + 1536)) 512" "$TEST_IMG" | _filter_qemu_io
 321 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 322 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 323
 324 # Write at middle: sector-wise, the request is: 128m... | -- 00 00 --
 325 _make_test_img $((size + 2048))
 326 $QEMU_IO -c "write -z $((size + 512)) 1024" "$TEST_IMG" | _filter_qemu_io
 327 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 328 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 329
 330 # Write entire cluster: sector-wise, the request is: 128m... | 00 00 00 00
 331 _make_test_img $((size + 2048))
 332 $QEMU_IO -c "write -z $size 2048" "$TEST_IMG" | _filter_qemu_io
 333 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 334 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 335
 336 # Repeat with backing file holding unallocated cluster.
 337 # TODO: Note that this forces an allocation, because we aren't yet able to
 338 # quickly detect that reads beyond EOF of the backing file are always zero
 339 CLUSTER_SIZE=2048 TEST_IMG="$TEST_IMG.base" _make_test_img $((size + 1024))
 340
 341 # Write at the front: sector-wise, the request is:
 342 # backing: 128m... | -- --
 343 # active:  128m... | 00 -- -- --
 344 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 345 $QEMU_IO -c "write -z $size 512" "$TEST_IMG" | _filter_qemu_io
 346 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 347 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 348
 349 # Write at the back: sector-wise, the request is:
 350 # backing: 128m... | -- --
 351 # active:  128m... | -- -- -- 00
 352 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 353 $QEMU_IO -c "write -z $((size + 1536)) 512" "$TEST_IMG" | _filter_qemu_io
 354 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 355 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 356
 357 # Write at middle: sector-wise, the request is:
 358 # backing: 128m... | -- --
 359 # active:  128m... | -- 00 00 --
 360 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 361 $QEMU_IO -c "write -z $((size + 512)) 1024" "$TEST_IMG" | _filter_qemu_io
 362 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 363 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 364
 365 # Write entire cluster: sector-wise, the request is:
 366 # backing: 128m... | -- --
 367 # active:  128m... | 00 00 00 00
 368 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 369 $QEMU_IO -c "write -z $size 2048" "$TEST_IMG" | _filter_qemu_io
 370 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 371 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 372
 373 # Repeat with backing file holding zero'd cluster
 374 # TODO: Note that this forces an allocation, because we aren't yet able to
 375 # quickly detect that reads beyond EOF of the backing file are always zero
 376 $QEMU_IO -c "write -z $size 512" "$TEST_IMG.base" | _filter_qemu_io
 377
 378 # Write at the front: sector-wise, the request is:
 379 # backing: 128m... | 00 00
 380 # active:  128m... | 00 -- -- --
 381 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 382 $QEMU_IO -c "write -z $size 512" "$TEST_IMG" | _filter_qemu_io
 383 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 384 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 385
 386 # Write at the back: sector-wise, the request is:
 387 # backing: 128m... | 00 00
 388 # active:  128m... | -- -- -- 00
 389 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 390 $QEMU_IO -c "write -z $((size + 1536)) 512" "$TEST_IMG" | _filter_qemu_io
 391 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 392 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 393
 394 # Write at middle: sector-wise, the request is:
 395 # backing: 128m... | 00 00
 396 # active:  128m... | -- 00 00 --
 397 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 398 $QEMU_IO -c "write -z $((size + 512)) 1024" "$TEST_IMG" | _filter_qemu_io
 399 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 400 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 401
 402 # Write entire cluster: sector-wise, the request is:
 403 # backing: 128m... | 00 00
 404 # active:  128m... | 00 00 00 00
 405 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 406 $QEMU_IO -c "write -z $size 2048" "$TEST_IMG" | _filter_qemu_io
 407 $QEMU_IO -c "alloc $size 2048" "$TEST_IMG" | _filter_qemu_io
 408 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 409
 410 # A preallocated cluster maintains its allocation, whether it stays as
 411 # data due to a partial write:
 412 # Convert 128m... | XX XX => ... | XX 00
 413 _make_test_img $((size + 1024))
 414 $QEMU_IO -c "write -P 1 $((size)) 1024" "$TEST_IMG" | _filter_qemu_io
 415 $QEMU_IO -c "write -z $((size + 512)) 512" "$TEST_IMG" | _filter_qemu_io
 416 $QEMU_IO -c "read -P 1 $((size)) 512" "$TEST_IMG" | _filter_qemu_io
 417 $QEMU_IO -c "read -P 0 $((size + 512)) 512" "$TEST_IMG" | _filter_qemu_io
 418 $QEMU_IO -c "alloc $size 1024" "$TEST_IMG" | _filter_qemu_io
 419 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 420
 421 # or because it is the entire cluster and can use the zero flag:
 422 # Convert 128m... | XX XX => ... | 00 00
 423 $QEMU_IO -c "write -z $((size)) 1024" "$TEST_IMG" | _filter_qemu_io
 424 $QEMU_IO -c "alloc $size 1024" "$TEST_IMG" | _filter_qemu_io
 425 $QEMU_IO -c "read -P 0 $size 1024" "$TEST_IMG" | _filter_qemu_io
 426 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 427
 428 echo
 429 echo == unaligned image tail cluster, allocation required ==
 430
 431 # Write beyond backing file must COW
 432 # Backing file: 128m... | XX --
 433 # Active layer: 128m... | -- -- 00 --
 434 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $((size + 1024))
 435 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 436 $QEMU_IO -c "write -P 1 $((size)) 512" "$TEST_IMG.base" | _filter_qemu_io
 437 $QEMU_IO -c "write -z $((size + 1024)) 512" "$TEST_IMG" | _filter_qemu_io
 438 $QEMU_IO -c "read -P 1 $((size)) 512" "$TEST_IMG" | _filter_qemu_io
 439 $QEMU_IO -c "read -P 0 $((size + 512)) 1536" "$TEST_IMG" | _filter_qemu_io
 440 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 441
 442 # Writes at boundaries of (partial) cluster must not lose mid-cluster data
 443 # Backing file: 128m: ... | -- XX
 444 # Active layer: 128m: ... | 00 -- -- 00
 445 CLUSTER_SIZE=512 TEST_IMG="$TEST_IMG.base" _make_test_img $((size + 1024))
 446 _make_test_img -b "$TEST_IMG.base" $((size + 2048))
 447 $QEMU_IO -c "write -P 1 $((size + 512)) 512" "$TEST_IMG.base" | _filter_qemu_io
 448 $QEMU_IO -c "write -z $((size)) 512" "$TEST_IMG" | _filter_qemu_io
 449 $QEMU_IO -c "read -P 0 $((size)) 512" "$TEST_IMG" | _filter_qemu_io
 450 $QEMU_IO -c "read -P 1 $((size + 512)) 512" "$TEST_IMG" | _filter_qemu_io
 451 $QEMU_IO -c "read -P 0 $((size + 1024)) 1024" "$TEST_IMG" | _filter_qemu_io
 452 $QEMU_IO -c "write -z $((size + 1536)) 512" "$TEST_IMG" | _filter_qemu_io
 453 $QEMU_IO -c "read -P 0 $((size)) 512" "$TEST_IMG" | _filter_qemu_io
 454 $QEMU_IO -c "read -P 1 $((size + 512)) 512" "$TEST_IMG" | _filter_qemu_io
 455 $QEMU_IO -c "read -P 0 $((size + 1024)) 1024" "$TEST_IMG" | _filter_qemu_io
 456 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 457
 458 # success, all done
 459 echo "*** done"
 460 rm -f $seq.full
 461 status=0