tests/qemu-iotests/250

   1 #!/usr/bin/env bash
   2 #
   3 # Test big discard in qcow2 shrink
   4 #
   5 # Copyright (c) 2019 Virtuozzo International GmbH. All rights reserved.
   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=vsementsov@virtuozzo.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 # This test checks that qcow2_process_discards does not truncate a discard
  44 # request > 2G.
  45 # To reproduce bug we need to overflow int by one sequential discard, so we
  46 # need size > 2G, bigger cluster size (as with default 64k we may have maximum
  47 # of 512M sequential data, corresponding to one L1 entry), and we need some
  48 # data of the beginning of the disk mapped to the end of file to prevent
  49 # bdrv_co_truncate(bs->file) call in qcow2_co_truncate(), which might succeed
  50 # anyway.
  51
  52 disk_usage()
  53 {
  54     du --block-size=1 $1 | awk '{print $1}'
  55 }
  56
  57 size=2100M
  58 IMGOPTS="cluster_size=1M,preallocation=metadata"
  59
  60 _make_test_img $size
  61 $QEMU_IO -c 'discard 0 10M' -c 'discard 2090M 10M' \
  62          -c 'write 2090M 10M' -c 'write 0 10M' "$TEST_IMG" | _filter_qemu_io
  63
  64 # Check that our trick with swapping first and last 10M chunks succeeded.
  65 # Otherwise test may pass even if bdrv_pdiscard() fails in
  66 # qcow2_process_discards()
  67 $QEMU_IMG map "$TEST_IMG" | _filter_testdir
  68
  69 before=$(disk_usage "$TEST_IMG")
  70 $QEMU_IMG resize --shrink "$TEST_IMG" 5M
  71 after=$(disk_usage "$TEST_IMG")
  72
  73 echo "Disk usage delta: $((before - after))"
  74
  75 # success, all done
  76 echo "*** done"
  77 rm -f $seq.full
  78 status=0