b39847a505
Saving icount as a parameters of the snapshot allows navigation between them in the execution replay scenario. This information can be used for finding a specific snapshot for proceeding the recorded execution to the specific moment of the time. E.g., 'reverse step' action (introduced in one of the following patches) needs to load the nearest snapshot which is prior to the current moment of time. This patch also updates snapshot test which verifies qemu monitor output. Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru> Acked-by: Markus Armbruster <armbru@redhat.com> Acked-by: Kevin Wolf <kwolf@redhat.com> -- v4 changes: - squashed format update with test output update v7 changes: - introduced the spaces between the fields in snapshot info output - updated the test to match new field widths Message-Id: <160174518865.12451.14327573383978752463.stgit@pasha-ThinkPad-X280> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
528 lines
16 KiB
Bash
Executable file
528 lines
16 KiB
Bash
Executable file
#!/usr/bin/env bash
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#
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# Test case for qcow2's handling of extra data in snapshot table entries
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# (and more generally, how certain cases of broken snapshot tables are
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# handled)
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#
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# Copyright (C) 2019 Red Hat, Inc.
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program. If not, see <http://www.gnu.org/licenses/>.
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#
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# creator
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owner=mreitz@redhat.com
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seq=$(basename $0)
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echo "QA output created by $seq"
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status=1 # failure is the default!
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_cleanup()
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{
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_cleanup_test_img
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rm -f "$TEST_IMG".v{2,3}.orig
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rm -f "$TEST_DIR"/sn{0,1,2}{,-pre,-extra,-post}
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}
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trap "_cleanup; exit \$status" 0 1 2 3 15
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# get standard environment, filters and checks
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. ./common.rc
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. ./common.filter
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# This tests qcow2-specific low-level functionality
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_supported_fmt qcow2
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_supported_proto file
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_supported_os Linux
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# (1) We create a v2 image that supports nothing but refcount_bits=16
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# (2) We do some refcount management on our own which expects
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# refcount_bits=16
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# As for data files, they do not support snapshots at all.
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_unsupported_imgopts 'refcount_bits=\([^1]\|.\([^6]\|$\)\)' data_file
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# Parameters:
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# $1: image filename
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# $2: snapshot table entry offset in the image
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snapshot_table_entry_size()
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{
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id_len=$(peek_file_be "$1" $(($2 + 12)) 2)
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name_len=$(peek_file_be "$1" $(($2 + 14)) 2)
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extra_len=$(peek_file_be "$1" $(($2 + 36)) 4)
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full_len=$((40 + extra_len + id_len + name_len))
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echo $(((full_len + 7) / 8 * 8))
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}
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# Parameter:
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# $1: image filename
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print_snapshot_table()
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{
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nb_entries=$(peek_file_be "$1" 60 4)
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offset=$(peek_file_be "$1" 64 8)
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echo "Snapshots in $1:" | _filter_testdir | _filter_imgfmt
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for ((i = 0; i < nb_entries; i++)); do
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id_len=$(peek_file_be "$1" $((offset + 12)) 2)
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name_len=$(peek_file_be "$1" $((offset + 14)) 2)
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extra_len=$(peek_file_be "$1" $((offset + 36)) 4)
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extra_ofs=$((offset + 40))
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id_ofs=$((extra_ofs + extra_len))
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name_ofs=$((id_ofs + id_len))
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echo " [$i]"
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echo " ID: $(peek_file_raw "$1" $id_ofs $id_len)"
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echo " Name: $(peek_file_raw "$1" $name_ofs $name_len)"
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echo " Extra data size: $extra_len"
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if [ $extra_len -ge 8 ]; then
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echo " VM state size: $(peek_file_be "$1" $extra_ofs 8)"
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fi
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if [ $extra_len -ge 16 ]; then
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echo " Disk size: $(peek_file_be "$1" $((extra_ofs + 8)) 8)"
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fi
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if [ $extra_len -ge 24 ]; then
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echo " Icount: $(peek_file_be "$1" $((extra_ofs + 16)) 8)"
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fi
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if [ $extra_len -gt 24 ]; then
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echo ' Unknown extra data:' \
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"$(peek_file_raw "$1" $((extra_ofs + 16)) $((extra_len - 16)) \
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| tr -d '\0')"
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fi
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offset=$((offset + $(snapshot_table_entry_size "$1" $offset)))
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done
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}
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# Mark clusters as allocated; works only in refblock 0 (i.e. before
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# cluster #32768).
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# Parameters:
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# $1: Start offset of what to allocate
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# $2: End offset (exclusive)
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refblock0_allocate()
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{
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reftable_ofs=$(peek_file_be "$TEST_IMG" 48 8)
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refblock_ofs=$(peek_file_be "$TEST_IMG" $reftable_ofs 8)
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cluster=$(($1 / 65536))
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ecluster=$((($2 + 65535) / 65536))
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while [ $cluster -lt $ecluster ]; do
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if [ $cluster -ge 32768 ]; then
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echo "*** Abort: Cluster $cluster exceeds refblock 0 ***"
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exit 1
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fi
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poke_file "$TEST_IMG" $((refblock_ofs + cluster * 2)) '\x00\x01'
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cluster=$((cluster + 1))
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done
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}
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echo
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echo '=== Create v2 template ==='
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echo
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# Create v2 image with a snapshot table with three entries:
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# [0]: No extra data (valid with v2, not valid with v3)
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# [1]: Has extra data unknown to qemu
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# [2]: Has the 64-bit VM state size, but not the disk size (again,
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# valid with v2, not valid with v3)
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TEST_IMG="$TEST_IMG.v2.orig" IMGOPTS='compat=0.10' _make_test_img 64M
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$QEMU_IMG snapshot -c sn0 "$TEST_IMG.v2.orig"
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$QEMU_IMG snapshot -c sn1 "$TEST_IMG.v2.orig"
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$QEMU_IMG snapshot -c sn2 "$TEST_IMG.v2.orig"
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# Copy out all existing snapshot table entries
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sn_table_ofs=$(peek_file_be "$TEST_IMG.v2.orig" 64 8)
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# ofs: Snapshot table entry offset
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# eds: Extra data size
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# ids: Name + ID size
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# len: Total entry length
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sn0_ofs=$sn_table_ofs
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sn0_eds=$(peek_file_be "$TEST_IMG.v2.orig" $((sn0_ofs + 36)) 4)
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sn0_ids=$(($(peek_file_be "$TEST_IMG.v2.orig" $((sn0_ofs + 12)) 2) +
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$(peek_file_be "$TEST_IMG.v2.orig" $((sn0_ofs + 14)) 2)))
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sn0_len=$(snapshot_table_entry_size "$TEST_IMG.v2.orig" $sn0_ofs)
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sn1_ofs=$((sn0_ofs + sn0_len))
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sn1_eds=$(peek_file_be "$TEST_IMG.v2.orig" $((sn1_ofs + 36)) 4)
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sn1_ids=$(($(peek_file_be "$TEST_IMG.v2.orig" $((sn1_ofs + 12)) 2) +
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$(peek_file_be "$TEST_IMG.v2.orig" $((sn1_ofs + 14)) 2)))
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sn1_len=$(snapshot_table_entry_size "$TEST_IMG.v2.orig" $sn1_ofs)
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sn2_ofs=$((sn1_ofs + sn1_len))
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sn2_eds=$(peek_file_be "$TEST_IMG.v2.orig" $((sn2_ofs + 36)) 4)
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sn2_ids=$(($(peek_file_be "$TEST_IMG.v2.orig" $((sn2_ofs + 12)) 2) +
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$(peek_file_be "$TEST_IMG.v2.orig" $((sn2_ofs + 14)) 2)))
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sn2_len=$(snapshot_table_entry_size "$TEST_IMG.v2.orig" $sn2_ofs)
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# Data before extra data
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dd if="$TEST_IMG.v2.orig" of="$TEST_DIR/sn0-pre" bs=1 skip=$sn0_ofs count=40 \
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&> /dev/null
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dd if="$TEST_IMG.v2.orig" of="$TEST_DIR/sn1-pre" bs=1 skip=$sn1_ofs count=40 \
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&> /dev/null
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dd if="$TEST_IMG.v2.orig" of="$TEST_DIR/sn2-pre" bs=1 skip=$sn2_ofs count=40 \
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&> /dev/null
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# Extra data
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dd if="$TEST_IMG.v2.orig" of="$TEST_DIR/sn0-extra" bs=1 \
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skip=$((sn0_ofs + 40)) count=$sn0_eds &> /dev/null
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dd if="$TEST_IMG.v2.orig" of="$TEST_DIR/sn1-extra" bs=1 \
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skip=$((sn1_ofs + 40)) count=$sn1_eds &> /dev/null
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dd if="$TEST_IMG.v2.orig" of="$TEST_DIR/sn2-extra" bs=1 \
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skip=$((sn2_ofs + 40)) count=$sn2_eds &> /dev/null
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# Data after extra data
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dd if="$TEST_IMG.v2.orig" of="$TEST_DIR/sn0-post" bs=1 \
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skip=$((sn0_ofs + 40 + sn0_eds)) count=$sn0_ids \
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&> /dev/null
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dd if="$TEST_IMG.v2.orig" of="$TEST_DIR/sn1-post" bs=1 \
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skip=$((sn1_ofs + 40 + sn1_eds)) count=$sn1_ids \
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&> /dev/null
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dd if="$TEST_IMG.v2.orig" of="$TEST_DIR/sn2-post" bs=1 \
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skip=$((sn2_ofs + 40 + sn2_eds)) count=$sn2_ids \
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&> /dev/null
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# Amend them, one by one
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# Set sn0's extra data size to 0
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poke_file "$TEST_DIR/sn0-pre" 36 '\x00\x00\x00\x00'
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truncate -s 0 "$TEST_DIR/sn0-extra"
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# Grow sn0-post to pad
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truncate -s $(($(snapshot_table_entry_size "$TEST_DIR/sn0-pre") - 40)) \
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"$TEST_DIR/sn0-post"
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# Set sn1's extra data size to 50
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poke_file "$TEST_DIR/sn1-pre" 36 '\x00\x00\x00\x32'
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truncate -s 50 "$TEST_DIR/sn1-extra"
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poke_file "$TEST_DIR/sn1-extra" 24 'very important data'
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# Grow sn1-post to pad
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truncate -s $(($(snapshot_table_entry_size "$TEST_DIR/sn1-pre") - 90)) \
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"$TEST_DIR/sn1-post"
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# Set sn2's extra data size to 8
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poke_file "$TEST_DIR/sn2-pre" 36 '\x00\x00\x00\x08'
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truncate -s 8 "$TEST_DIR/sn2-extra"
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# Grow sn2-post to pad
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truncate -s $(($(snapshot_table_entry_size "$TEST_DIR/sn2-pre") - 48)) \
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"$TEST_DIR/sn2-post"
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# Construct snapshot table
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cat "$TEST_DIR"/sn0-{pre,extra,post} \
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"$TEST_DIR"/sn1-{pre,extra,post} \
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"$TEST_DIR"/sn2-{pre,extra,post} \
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| dd of="$TEST_IMG.v2.orig" bs=1 seek=$sn_table_ofs conv=notrunc \
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&> /dev/null
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# Done!
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TEST_IMG="$TEST_IMG.v2.orig" _check_test_img
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print_snapshot_table "$TEST_IMG.v2.orig"
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echo
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echo '=== Upgrade to v3 ==='
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echo
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cp "$TEST_IMG.v2.orig" "$TEST_IMG.v3.orig"
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$QEMU_IMG amend -o compat=1.1 "$TEST_IMG.v3.orig"
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TEST_IMG="$TEST_IMG.v3.orig" _check_test_img
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print_snapshot_table "$TEST_IMG.v3.orig"
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echo
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echo '=== Repair botched v3 ==='
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echo
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# Force the v2 file to be v3. v3 requires each snapshot table entry
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# to have at least 16 bytes of extra data, so it will not comply to
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# the qcow2 v3 specification; but we can fix that.
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cp "$TEST_IMG.v2.orig" "$TEST_IMG"
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# Set version
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poke_file "$TEST_IMG" 4 '\x00\x00\x00\x03'
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# Increase header length (necessary for v3)
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poke_file "$TEST_IMG" 100 '\x00\x00\x00\x68'
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# Set refcount order (necessary for v3)
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poke_file "$TEST_IMG" 96 '\x00\x00\x00\x04'
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_check_test_img -r all
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print_snapshot_table "$TEST_IMG"
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# From now on, just test the qcow2 version we are supposed to test.
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# (v3 by default, v2 by choice through $IMGOPTS.)
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# That works because we always write all known extra data when
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# updating the snapshot table, independent of the version.
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if echo "$IMGOPTS" | grep -q 'compat=\(0\.10\|v2\)' 2> /dev/null; then
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subver=v2
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else
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subver=v3
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fi
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echo
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echo '=== Add new snapshot ==='
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echo
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cp "$TEST_IMG.$subver.orig" "$TEST_IMG"
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$QEMU_IMG snapshot -c sn3 "$TEST_IMG"
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_check_test_img
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print_snapshot_table "$TEST_IMG"
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echo
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echo '=== Remove different snapshots ==='
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for sn in sn0 sn1 sn2; do
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echo
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echo "--- $sn ---"
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cp "$TEST_IMG.$subver.orig" "$TEST_IMG"
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$QEMU_IMG snapshot -d $sn "$TEST_IMG"
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_check_test_img
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print_snapshot_table "$TEST_IMG"
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done
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echo
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echo '=== Reject too much unknown extra data ==='
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echo
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cp "$TEST_IMG.$subver.orig" "$TEST_IMG"
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$QEMU_IMG snapshot -c sn3 "$TEST_IMG"
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sn_table_ofs=$(peek_file_be "$TEST_IMG" 64 8)
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sn0_ofs=$sn_table_ofs
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sn1_ofs=$((sn0_ofs + $(snapshot_table_entry_size "$TEST_IMG" $sn0_ofs)))
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sn2_ofs=$((sn1_ofs + $(snapshot_table_entry_size "$TEST_IMG" $sn1_ofs)))
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sn3_ofs=$((sn2_ofs + $(snapshot_table_entry_size "$TEST_IMG" $sn2_ofs)))
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# 64 kB of extra data should be rejected
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# (Note that this also induces a refcount error, because it spills
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# over to the next cluster. That's a good way to test that we can
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# handle simultaneous snapshot table and refcount errors.)
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poke_file "$TEST_IMG" $((sn3_ofs + 36)) '\x00\x01\x00\x00'
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# Print error
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_img_info
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echo
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_check_test_img
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echo
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# Should be repairable
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_check_test_img -r all
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echo
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echo '=== Snapshot table too big ==='
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echo
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sn_table_ofs=$(peek_file_be "$TEST_IMG.v3.orig" 64 8)
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# Fill a snapshot with 1 kB of extra data, a 65535-char ID, and a
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# 65535-char name, and repeat it as many times as necessary to fill
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# 64 MB (the maximum supported by qemu)
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touch "$TEST_DIR/sn0"
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# Full size (fixed + extra + ID + name + padding)
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sn_size=$((40 + 1024 + 65535 + 65535 + 2))
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# We only need the fixed part, though.
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truncate -s 40 "$TEST_DIR/sn0"
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# 65535-char ID string
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poke_file "$TEST_DIR/sn0" 12 '\xff\xff'
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# 65535-char name
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poke_file "$TEST_DIR/sn0" 14 '\xff\xff'
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# 1 kB of extra data
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poke_file "$TEST_DIR/sn0" 36 '\x00\x00\x04\x00'
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# Create test image
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_make_test_img 64M
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# Hook up snapshot table somewhere safe (at 1 MB)
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poke_file "$TEST_IMG" 64 '\x00\x00\x00\x00\x00\x10\x00\x00'
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offset=1048576
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size_written=0
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sn_count=0
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while [ $size_written -le $((64 * 1048576)) ]; do
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dd if="$TEST_DIR/sn0" of="$TEST_IMG" bs=1 seek=$offset conv=notrunc \
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&> /dev/null
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offset=$((offset + sn_size))
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size_written=$((size_written + sn_size))
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sn_count=$((sn_count + 1))
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done
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truncate -s "$offset" "$TEST_IMG"
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# Give the last snapshot (the one to be removed) an L1 table so we can
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# see how that is handled when repairing the image
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# (Put it two clusters before 1 MB, and one L2 table one cluster
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# before 1 MB)
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poke_file "$TEST_IMG" $((offset - sn_size + 0)) \
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'\x00\x00\x00\x00\x00\x0e\x00\x00'
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poke_file "$TEST_IMG" $((offset - sn_size + 8)) \
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'\x00\x00\x00\x01'
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# Hook up the L2 table
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poke_file "$TEST_IMG" $((1048576 - 2 * 65536)) \
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'\x80\x00\x00\x00\x00\x0f\x00\x00'
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# Make sure all of the clusters we just hooked up are allocated:
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# - The snapshot table
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# - The last snapshot's L1 and L2 table
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refblock0_allocate $((1048576 - 2 * 65536)) $offset
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poke_file "$TEST_IMG" 60 \
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"$(printf '%08x' $sn_count | sed -e 's/\(..\)/\\x\1/g')"
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# Print error
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_img_info
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echo
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_check_test_img
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echo
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# Should be repairable
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_check_test_img -r all
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echo
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echo "$((sn_count - 1)) snapshots should remain:"
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echo " qemu-img info reports $(_img_info | grep -c '^ \{32\}') snapshots"
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echo " Image header reports $(peek_file_be "$TEST_IMG" 60 4) snapshots"
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echo
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echo '=== Snapshot table too big with one entry with too much extra data ==='
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echo
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# For this test, we reuse the image from the previous case, which has
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# a snapshot table that is right at the limit.
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# Our layout looks like this:
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# - (a number of snapshot table entries)
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# - One snapshot with $extra_data_size extra data
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# - One normal snapshot that breaks the 64 MB boundary
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# - One normal snapshot beyond the 64 MB boundary
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#
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# $extra_data_size is calculated so that simply by virtue of it
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# decreasing to 1 kB, the penultimate snapshot will fit into 64 MB
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# limit again. The final snapshot will always be beyond the limit, so
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# that we can see that the repair algorithm does still determine the
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# limit to be somewhere, even when truncating one snapshot's extra
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# data.
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# The last case has removed the last snapshot, so calculate
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# $old_offset to get the current image's real length
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old_offset=$((offset - sn_size))
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# The layout from the previous test had one snapshot beyond the 64 MB
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# limit; we want the same (after the oversized extra data has been
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# truncated to 1 kB), so we drop the last three snapshots and
|
|
# construct them from scratch.
|
|
offset=$((offset - 3 * sn_size))
|
|
sn_count=$((sn_count - 3))
|
|
|
|
# Assuming we had already written one of the three snapshots
|
|
# (necessary so we can calculate $extra_data_size next).
|
|
size_written=$((size_written - 2 * sn_size))
|
|
|
|
# Increase the extra data size so we go past the limit
|
|
# (The -1024 comes from the 1 kB of extra data we already have)
|
|
extra_data_size=$((64 * 1048576 + 8 - sn_size - (size_written - 1024)))
|
|
|
|
poke_file "$TEST_IMG" $((offset + 36)) \
|
|
"$(printf '%08x' $extra_data_size | sed -e 's/\(..\)/\\x\1/g')"
|
|
|
|
offset=$((offset + sn_size - 1024 + extra_data_size))
|
|
size_written=$((size_written - 1024 + extra_data_size))
|
|
sn_count=$((sn_count + 1))
|
|
|
|
# Write the two normal snapshots
|
|
for ((i = 0; i < 2; i++)); do
|
|
dd if="$TEST_DIR/sn0" of="$TEST_IMG" bs=1 seek=$offset conv=notrunc \
|
|
&> /dev/null
|
|
offset=$((offset + sn_size))
|
|
size_written=$((size_written + sn_size))
|
|
sn_count=$((sn_count + 1))
|
|
|
|
if [ $i = 0 ]; then
|
|
# Check that the penultimate snapshot is beyond the 64 MB limit
|
|
echo "Snapshot table size should equal $((64 * 1048576 + 8)):" \
|
|
$size_written
|
|
echo
|
|
fi
|
|
done
|
|
|
|
truncate -s $offset "$TEST_IMG"
|
|
refblock0_allocate $old_offset $offset
|
|
|
|
poke_file "$TEST_IMG" 60 \
|
|
"$(printf '%08x' $sn_count | sed -e 's/\(..\)/\\x\1/g')"
|
|
|
|
# Print error
|
|
_img_info
|
|
echo
|
|
_check_test_img
|
|
echo
|
|
|
|
# Just truncating the extra data should be sufficient to shorten the
|
|
# snapshot table so only one snapshot exceeds the extra size
|
|
_check_test_img -r all
|
|
|
|
echo
|
|
echo '=== Too many snapshots ==='
|
|
echo
|
|
|
|
# Create a v2 image, for speeds' sake: All-zero snapshot table entries
|
|
# are only valid in v2.
|
|
IMGOPTS='compat=0.10' _make_test_img 64M
|
|
|
|
# Hook up snapshot table somewhere safe (at 1 MB)
|
|
poke_file "$TEST_IMG" 64 '\x00\x00\x00\x00\x00\x10\x00\x00'
|
|
# "Create" more than 65536 snapshots (twice that many here)
|
|
poke_file "$TEST_IMG" 60 '\x00\x02\x00\x00'
|
|
|
|
# 40-byte all-zero snapshot table entries are valid snapshots, but
|
|
# only in v2 (v3 needs 16 bytes of extra data, so we would have to
|
|
# write 131072x '\x10').
|
|
truncate -s $((1048576 + 40 * 131072)) "$TEST_IMG"
|
|
|
|
# But let us give one of the snapshots to be removed an L1 table so
|
|
# we can see how that is handled when repairing the image.
|
|
# (Put it two clusters before 1 MB, and one L2 table one cluster
|
|
# before 1 MB)
|
|
poke_file "$TEST_IMG" $((1048576 + 40 * 65536 + 0)) \
|
|
'\x00\x00\x00\x00\x00\x0e\x00\x00'
|
|
poke_file "$TEST_IMG" $((1048576 + 40 * 65536 + 8)) \
|
|
'\x00\x00\x00\x01'
|
|
|
|
# Hook up the L2 table
|
|
poke_file "$TEST_IMG" $((1048576 - 2 * 65536)) \
|
|
'\x80\x00\x00\x00\x00\x0f\x00\x00'
|
|
|
|
# Make sure all of the clusters we just hooked up are allocated:
|
|
# - The snapshot table
|
|
# - The last snapshot's L1 and L2 table
|
|
refblock0_allocate $((1048576 - 2 * 65536)) $((1048576 + 40 * 131072))
|
|
|
|
# Print error
|
|
_img_info
|
|
echo
|
|
_check_test_img
|
|
echo
|
|
|
|
# Should be repairable
|
|
_check_test_img -r all
|
|
|
|
echo
|
|
echo '65536 snapshots should remain:'
|
|
echo " qemu-img info reports $(_img_info | grep -c '^ \{32\}') snapshots"
|
|
echo " Image header reports $(peek_file_be "$TEST_IMG" 60 4) snapshots"
|
|
|
|
# success, all done
|
|
echo "*** done"
|
|
status=0
|