cachepc-qemu

Fork of AMDESE/qemu with changes for cachepc side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-qemu
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      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
     23owner=mreitz@redhat.com
     24
     25seq="$(basename $0)"
     26echo "QA output created by $seq"
     27
     28status=1	# failure is the default!
     29
     30_cleanup()
     31{
     32	_cleanup_test_img
     33}
     34trap "_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
     46echo
     47echo '=== Testing large refcount and L1 table ==='
     48echo
     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
     90echo '*** done'
     91rm -f $seq.full
     92status=0