tests/qemu-iotests/115

   1 #!/bin/bash
   2 #
   3 # Test case for non-self-referential qcow2 refcount blocks
   4 #
   5 # Copyright (C) 2014 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=mreitz@redhat.com
  23
  24 seq="$(basename $0)"
  25 echo "QA output created by $seq"
  26
  27 here="$PWD"
  28 tmp=/tmp/$$
  29 status=1        # failure is the default!
  30
  31 _cleanup()
  32 {
  33         _cleanup_test_img
  34 }
  35 trap "_cleanup; exit \$status" 0 1 2 3 15
  36
  37 # get standard environment, filters and checks
  38 . ./common.rc
  39 . ./common.filter
  40
  41 _supported_fmt qcow2
  42 _supported_proto file
  43 _supported_os Linux
  44 # This test relies on refcounts being 64 bits wide (which does not work with
  45 # compat=0.10)
  46 _unsupported_imgopts 'refcount_bits=\([^6]\|.\([^4]\|$\)\)' 'compat=0.10'
  47
  48 echo
  49 echo '=== Testing large refcount and L1 table ==='
  50 echo
  51
  52 # Create an image with an L1 table and a refcount table that each span twice the
  53 # number of clusters which can be described by a single refblock; therefore, at
  54 # least two refblocks cannot count their own refcounts because all the clusters
  55 # they describe are part of the L1 table or refcount table.
  56
  57 # One refblock can describe (with cluster_size=512 and refcount_bits=64)
  58 # 512/8 = 64 clusters, therefore the L1 table should cover 128 clusters, which
  59 # equals 128 * (512/8) = 8192 entries (actually, 8192 - 512/8 = 8129 would
  60 # suffice, but it does not really matter). 8192 L2 tables can in turn describe
  61 # 8192 * 512/8 = 524,288 clusters which cover a space of 256 MB.
  62
  63 # Since with refcount_bits=64 every refcount block entry is 64 bits wide (just
  64 # like the L2 table entries), the same calculation applies to the refcount table
  65 # as well; the difference is that while for the L1 table the guest disk size is
  66 # concerned, for the refcount table it is the image length that has to be at
  67 # least 256 MB. We can achieve that by using preallocation=metadata for an image
  68 # which has a guest disk size of 256 MB.
  69
  70 IMGOPTS="$IMGOPTS,refcount_bits=64,cluster_size=512,preallocation=metadata" \
  71     _make_test_img 256M
  72
  73 # We know for sure that the L1 and refcount tables do not overlap with any other
  74 # structure because the metadata overlap checks would have caught that case.
  75
  76 # Because qemu refuses to open qcow2 files whose L1 table does not cover the
  77 # whole guest disk size, it is definitely large enough. On the other hand, to
  78 # test whether the refcount table is large enough, we simply have to verify that
  79 # indeed all the clusters are allocated, which is done by qemu-img check.
  80
  81 # The final thing we need to test is whether the tables are actually covered by
  82 # refcount blocks; since all clusters of the tables are referenced, we can use
  83 # qemu-img check for that purpose, too.
  84
  85 $QEMU_IMG check "$TEST_IMG" | \
  86     sed -e 's/^.* = \([0-9]\+\.[0-9]\+% allocated\).*\(clusters\)$/\1 \2/' \
  87         -e '/^Image end offset/d'
  88
  89 # (Note that we cannot use _check_test_img because that function filters out the
  90 # allocation status)
  91
  92 # success, all done
  93 echo '*** done'
  94 rm -f $seq.full
  95 status=0