tests/qemu-iotests/220

   1 #!/usr/bin/env bash
   2 # group: rw auto
   3 #
   4 # max limits on compression in huge qcow2 files
   5 #
   6 # Copyright (C) 2018 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 seq=$(basename $0)
  23 echo "QA output created by $seq"
  24
  25 status=1    # failure is the default!
  26
  27 _cleanup()
  28 {
  29     _cleanup_test_img
  30 }
  31 trap "_cleanup; exit \$status" 0 1 2 3 15
  32
  33 # get standard environment, filters and checks
  34 . ./common.rc
  35 . ./common.filter
  36 . ./common.pattern
  37
  38 _supported_fmt qcow2
  39 _supported_proto file fuse
  40 _supported_os Linux
  41 # To use a different refcount width but 16 bits we need compat=1.1,
  42 # and external data files do not support compressed clusters.
  43 _unsupported_imgopts 'compat=0.10' data_file
  44
  45 echo "== Creating huge file =="
  46
  47 # Sanity check: We require a file system that permits the creation
  48 # of a HUGE (but very sparse) file.  tmpfs works, ext4 does not.
  49 _require_large_file 513T
  50
  51 _make_test_img -o 'cluster_size=2M,refcount_bits=1' 513T
  52
  53 echo "== Populating refcounts =="
  54 # We want an image with 256M refcounts * 2M clusters = 512T referenced.
  55 # Each 2M cluster holds 16M refcounts; the refcount table initially uses
  56 # 1 refblock, so we need to add 15 more.  The refcount table lives at 2M,
  57 # first refblock at 4M, L2 at 6M, so our remaining additions start at 8M.
  58 # Then, for each refblock, mark it as fully populated.
  59 to_hex() {
  60     printf %016x\\n $1 | sed 's/\(..\)/\\x\1/g'
  61 }
  62 truncate --size=38m "$TEST_IMG"
  63 entry=$((0x200000))
  64 $QEMU_IO_PROG -f raw -c "w -P 0xff 4m 2m" "$TEST_IMG" | _filter_qemu_io
  65 for i in {1..15}; do
  66     offs=$((0x600000 + i*0x200000))
  67     poke_file "$TEST_IMG" $((i*8 + entry)) $(to_hex $offs)
  68     $QEMU_IO_PROG -f raw -c "w -P 0xff $offs 2m" "$TEST_IMG" | _filter_qemu_io
  69 done
  70
  71 echo "== Checking file before =="
  72 # FIXME: 'qemu-img check' doesn't diagnose refcounts beyond the end of
  73 # the file as leaked clusters
  74 _check_test_img 2>&1 | sed '/^Leaked cluster/d'
  75 stat -c 'image size %s' "$TEST_IMG"
  76
  77 echo "== Trying to write compressed cluster =="
  78 # Given our file size, the next available cluster at 512T lies beyond the
  79 # maximum offset that a compressed 2M cluster can reside in
  80 $QEMU_IO_PROG -c 'w -c 0 2m' "$TEST_IMG" | _filter_qemu_io
  81 # The attempt failed, but ended up allocating a new refblock
  82 stat -c 'image size %s' "$TEST_IMG"
  83
  84 echo "== Writing normal cluster =="
  85 # The failed write should not corrupt the image, so a normal write succeeds
  86 $QEMU_IO_PROG -c 'w 0 2m' "$TEST_IMG" | _filter_qemu_io
  87
  88 echo "== Checking file after =="
  89 # qemu-img now sees the millions of leaked clusters, thanks to the allocations
  90 # at 512T.  Undo many of our faked references to speed up the check.
  91 $QEMU_IO_PROG -f raw -c "w -z 5m 1m" -c "w -z 8m 30m" "$TEST_IMG" |
  92     _filter_qemu_io
  93 _check_test_img 2>&1 | sed '/^Leaked cluster/d'
  94
  95 # success, all done
  96 echo "*** done"
  97 rm -f $seq.full
  98 status=0