tests/qemu-iotests/115

   1 #!/usr/bin/env bash
   2 # group: rw
   3 #
   4 # Test case for non-self-referential qcow2 refcount blocks
   5 #
   6 # Copyright (C) 2014 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 # creator
  23 owner=mreitz@redhat.com
  24
  25 seq="$(basename $0)"
  26 echo "QA output created by $seq"
  27
  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 fuse
  42 # This test relies on refcounts being 64 bits wide (which does not work with
  43 # compat=0.10)
  44 _unsupported_imgopts 'refcount_bits=\([^6]\|.\([^4]\|$\)\)' 'compat=0.10'
  45
  46 echo
  47 echo '=== Testing large refcount and L1 table ==='
  48 echo
  49
  50 # Create an image with an L1 table and a refcount table that each span twice the
  51 # number of clusters which can be described by a single refblock; therefore, at
  52 # least two refblocks cannot count their own refcounts because all the clusters
  53 # they describe are part of the L1 table or refcount table.
  54
  55 # One refblock can describe (with cluster_size=512 and refcount_bits=64)
  56 # 512/8 = 64 clusters, therefore the L1 table should cover 128 clusters, which
  57 # equals 128 * (512/8) = 8192 entries (actually, 8192 - 512/8 = 8129 would
  58 # suffice, but it does not really matter). 8192 L2 tables can in turn describe
  59 # 8192 * 512/8 = 524,288 clusters which cover a space of 256 MB.
  60
  61 # Since with refcount_bits=64 every refcount block entry is 64 bits wide (just
  62 # like the L2 table entries), the same calculation applies to the refcount table
  63 # as well; the difference is that while for the L1 table the guest disk size is
  64 # concerned, for the refcount table it is the image length that has to be at
  65 # least 256 MB. We can achieve that by using preallocation=metadata for an image
  66 # which has a guest disk size of 256 MB.
  67
  68 _make_test_img -o "refcount_bits=64,cluster_size=512,preallocation=metadata" 256M
  69
  70 # We know for sure that the L1 and refcount tables do not overlap with any other
  71 # structure because the metadata overlap checks would have caught that case.
  72
  73 # Because qemu refuses to open qcow2 files whose L1 table does not cover the
  74 # whole guest disk size, it is definitely large enough. On the other hand, to
  75 # test whether the refcount table is large enough, we simply have to verify that
  76 # indeed all the clusters are allocated, which is done by qemu-img check.
  77
  78 # The final thing we need to test is whether the tables are actually covered by
  79 # refcount blocks; since all clusters of the tables are referenced, we can use
  80 # qemu-img check for that purpose, too.
  81
  82 $QEMU_IMG check "$TEST_IMG" | \
  83     sed -e 's/^.* = \([0-9]\+\.[0-9]\+% allocated\).*\(clusters\)$/\1 \2/' \
  84         -e '/^Image end offset/d'
  85
  86 # (Note that we cannot use _check_test_img because that function filters out the
  87 # allocation status)
  88
  89 # success, all done
  90 echo '*** done'
  91 rm -f $seq.full
  92 status=0