tests/qemu-iotests/179

   1 #!/usr/bin/env bash
   2 #
   3 # Test case for write zeroes with unmap
   4 #
   5 # Copyright (C) 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=eblake@redhat.com
  23
  24 seq="$(basename $0)"
  25 echo "QA output created by $seq"
  26
  27 status=1        # failure is the default!
  28
  29 _cleanup()
  30 {
  31         _cleanup_test_img
  32     rm -f "$TEST_DIR/blkdebug.conf"
  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 # v2 images can't mark clusters as zero
  45 _unsupported_imgopts compat=0.10
  46
  47 echo
  48 echo '=== Testing write zeroes with unmap ==='
  49 echo
  50
  51 TEST_IMG="$TEST_IMG.base" _make_test_img 64M
  52 _make_test_img -b "$TEST_IMG.base"
  53
  54 # Offsets chosen at or near 2M boundaries so test works at all cluster sizes
  55 # 8k and larger (smaller clusters fail due to non-contiguous allocations)
  56
  57 # Aligned writes to unallocated cluster should not allocate mapping, but must
  58 # mark cluster as zero, whether or not unmap was requested
  59 $QEMU_IO -c "write -z -u 2M 2M" "$TEST_IMG.base" | _filter_qemu_io
  60 $QEMU_IO -c "write -z 6M 2M" "$TEST_IMG.base" | _filter_qemu_io
  61 $QEMU_IO -c "map" "$TEST_IMG.base" | _filter_qemu_io
  62 $QEMU_IMG map --output=json "$TEST_IMG.base" | _filter_qemu_img_map
  63
  64 # Unaligned writes need not allocate mapping if the cluster already reads
  65 # as zero, but must mark cluster as zero, whether or not unmap was requested
  66 $QEMU_IO -c "write -z -u 10485761 2097150" "$TEST_IMG.base" | _filter_qemu_io
  67 $QEMU_IO -c "write -z 14680065 2097150" "$TEST_IMG.base" | _filter_qemu_io
  68 $QEMU_IO -c "map" "$TEST_IMG.base" | _filter_qemu_io
  69 $QEMU_IMG map --output=json "$TEST_IMG.base" | _filter_qemu_img_map
  70
  71 # Requesting unmap of normal data must deallocate; omitting unmap should
  72 # preserve the mapping
  73 $QEMU_IO -c "write 18M 14M" "$TEST_IMG.base" | _filter_qemu_io
  74 $QEMU_IO -c "write -z -u 20M 2M" "$TEST_IMG.base" | _filter_qemu_io
  75 $QEMU_IO -c "write -z 24M 6M" "$TEST_IMG.base" | _filter_qemu_io
  76 $QEMU_IO -c "map" "$TEST_IMG.base" | _filter_qemu_io
  77 $QEMU_IMG map --output=json "$TEST_IMG.base" | _filter_qemu_img_map
  78
  79 # Likewise when writing on already-mapped zero data
  80 $QEMU_IO -c "write -z -u 26M 2M" "$TEST_IMG.base" | _filter_qemu_io
  81 $QEMU_IO -c "write -z 28M 2M" "$TEST_IMG.base" | _filter_qemu_io
  82 $QEMU_IO -c "map" "$TEST_IMG.base" | _filter_qemu_io
  83 $QEMU_IMG map --output=json "$TEST_IMG.base" | _filter_qemu_img_map
  84
  85 # Writing on unmapped zeroes does not allocate
  86 $QEMU_IO -c "write -z 32M 8M" "$TEST_IMG.base" | _filter_qemu_io
  87 $QEMU_IO -c "write -z -u 34M 2M" "$TEST_IMG.base" | _filter_qemu_io
  88 $QEMU_IO -c "write -z 36M 2M" "$TEST_IMG.base" | _filter_qemu_io
  89 $QEMU_IO -c "map" "$TEST_IMG.base" | _filter_qemu_io
  90 $QEMU_IMG map --output=json "$TEST_IMG.base" | _filter_qemu_img_map
  91
  92 # Writing zero overrides a backing file, regardless of backing cluster type
  93 $QEMU_IO -c "write -z 40M 8M" "$TEST_IMG.base" | _filter_qemu_io
  94 $QEMU_IO -c "write 48M 8M" "$TEST_IMG.base" | _filter_qemu_io
  95 $QEMU_IO -c "write -z -u 42M 2M" "$TEST_IMG" | _filter_qemu_io
  96 $QEMU_IO -c "write -z 44M 2M" "$TEST_IMG" | _filter_qemu_io
  97 $QEMU_IO -c "write -z -u 50M 2M" "$TEST_IMG" | _filter_qemu_io
  98 $QEMU_IO -c "write -z 52M 2M" "$TEST_IMG" | _filter_qemu_io
  99 $QEMU_IO -c "write -z -u 58M 2M" "$TEST_IMG" | _filter_qemu_io
 100 $QEMU_IO -c "write -z 60M 2M" "$TEST_IMG" | _filter_qemu_io
 101 $QEMU_IO -c "map" "$TEST_IMG" | _filter_qemu_io
 102 $QEMU_IMG map --output=json "$TEST_IMG" | _filter_qemu_img_map
 103
 104 # Final check that mappings are correct and images are still sane
 105 TEST_IMG="$TEST_IMG.base" _check_test_img
 106 _check_test_img
 107
 108 echo
 109 echo '=== Testing cache optimization ==='
 110 echo
 111
 112 BLKDBG_TEST_IMG="blkdebug:$TEST_DIR/blkdebug.conf:$TEST_IMG.base"
 113
 114 cat > "$TEST_DIR/blkdebug.conf" <<EOF
 115 [inject-error]
 116 event = "l2_update"
 117 errno = "5"
 118 immediately = "on"
 119 once = "off"
 120 EOF
 121
 122 # None of the following writes should trigger an L2 update, because the
 123 # cluster already reads as zero, and we don't have to change allocation
 124 $QEMU_IO -c "w -z -u 20M 2M" "$BLKDBG_TEST_IMG" | _filter_qemu_io
 125 $QEMU_IO -c "w -z 20M 2M" "$BLKDBG_TEST_IMG" | _filter_qemu_io
 126 $QEMU_IO -c "w -z 28M 2M" "$BLKDBG_TEST_IMG" | _filter_qemu_io
 127
 128 # success, all done
 129 echo '*** done'
 130 status=0