524 lines
16 KiB
Plaintext
524 lines
16 KiB
Plaintext
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#!/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 qocw2-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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_unsupported_imgopts 'refcount_bits=\([^1]\|.\([^6]\|$\)\)'
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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 [ $extra_len -gt 16 ]; then
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echo ' Unknown extra data:' \
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"$(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 42
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poke_file "$TEST_DIR/sn1-pre" 36 '\x00\x00\x00\x2a'
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truncate -s 42 "$TEST_DIR/sn1-extra"
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poke_file "$TEST_DIR/sn1-extra" 16 'very important data'
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# Grow sn1-post to pad
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truncate -s $(($(snapshot_table_entry_size "$TEST_DIR/sn1-pre") - 82)) \
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"$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=$((40 + 1024 + 65535 + 65535 + 2))
|
||
|
|
|
||
|
|
# We only need the fixed part, though.
|
||
|
|
truncate -s 40 "$TEST_DIR/sn0"
|
||
|
|
|
||
|
|
# 65535-char ID string
|
||
|
|
poke_file "$TEST_DIR/sn0" 12 '\xff\xff'
|
||
|
|
# 65535-char name
|
||
|
|
poke_file "$TEST_DIR/sn0" 14 '\xff\xff'
|
||
|
|
# 1 kB of extra data
|
||
|
|
poke_file "$TEST_DIR/sn0" 36 '\x00\x00\x04\x00'
|
||
|
|
|
||
|
|
# Create test image
|
||
|
|
_make_test_img 64M
|
||
|
|
|
||
|
|
# Hook up snapshot table somewhere safe (at 1 MB)
|
||
|
|
poke_file "$TEST_IMG" 64 '\x00\x00\x00\x00\x00\x10\x00\x00'
|
||
|
|
|
||
|
|
offset=1048576
|
||
|
|
size_written=0
|
||
|
|
sn_count=0
|
||
|
|
while [ $size_written -le $((64 * 1048576)) ]; do
|
||
|
|
dd if="$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=$((sn_count + 1))
|
||
|
|
done
|
||
|
|
truncate -s "$offset" "$TEST_IMG"
|
||
|
|
|
||
|
|
# Give the last snapshot (the one to be removed) an L1 table so we can
|
||
|
|
# see how that is handled when repairing the image
|
||
|
|
# (Put it two clusters before 1 MB, and one L2 table one cluster
|
||
|
|
# before 1 MB)
|
||
|
|
poke_file "$TEST_IMG" $((offset - sn_size + 0)) \
|
||
|
|
'\x00\x00\x00\x00\x00\x0e\x00\x00'
|
||
|
|
poke_file "$TEST_IMG" $((offset - sn_size + 8)) \
|
||
|
|
'\x00\x00\x00\x01'
|
||
|
|
|
||
|
|
# Hook up the L2 table
|
||
|
|
poke_file "$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)) $offset
|
||
|
|
|
||
|
|
poke_file "$TEST_IMG" 60 \
|
||
|
|
"$(printf '%08x' $sn_count | sed -e 's/\(..\)/\\x\1/g')"
|
||
|
|
|
||
|
|
# Print error
|
||
|
|
_img_info
|
||
|
|
echo
|
||
|
|
_check_test_img
|
||
|
|
echo
|
||
|
|
|
||
|
|
# Should be repairable
|
||
|
|
_check_test_img -r all
|
||
|
|
|
||
|
|
echo
|
||
|
|
echo "$((sn_count - 1)) snapshots should remain:"
|
||
|
|
echo " qemu-img info reports $(_img_info | grep -c '^ \{34\}') snapshots"
|
||
|
|
echo " Image header reports $(peek_file_be "$TEST_IMG" 60 4) snapshots"
|
||
|
|
|
||
|
|
echo
|
||
|
|
echo '=== Snapshot table too big with one entry with too much extra data ==='
|
||
|
|
echo
|
||
|
|
|
||
|
|
# For this test, we reuse the image from the previous case, which has
|
||
|
|
# a snapshot table that is right at the limit.
|
||
|
|
# Our layout looks like this:
|
||
|
|
# - (a number of snapshot table entries)
|
||
|
|
# - One snapshot with $extra_data_size extra data
|
||
|
|
# - One normal snapshot that breaks the 64 MB boundary
|
||
|
|
# - One normal snapshot beyond the 64 MB boundary
|
||
|
|
#
|
||
|
|
# $extra_data_size is calculated so that simply by virtue of it
|
||
|
|
# decreasing to 1 kB, the penultimate snapshot will fit into 64 MB
|
||
|
|
# limit again. The final snapshot will always be beyond the limit, so
|
||
|
|
# that we can see that the repair algorithm does still determine the
|
||
|
|
# limit to be somewhere, even when truncating one snapshot's extra
|
||
|
|
# data.
|
||
|
|
|
||
|
|
# The last case has removed the last snapshot, so calculate
|
||
|
|
# $old_offset to get the current image's real length
|
||
|
|
old_offset=$((offset - sn_size))
|
||
|
|
|
||
|
|
# The layout from the previous test had one snapshot beyond the 64 MB
|
||
|
|
# limit; we want the same (after the oversized extra data has been
|
||
|
|
# 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 '^ \{34\}') snapshots"
|
||
|
|
echo " Image header reports $(peek_file_be "$TEST_IMG" 60 4) snapshots"
|
||
|
|
|
||
|
|
# success, all done
|
||
|
|
echo "*** done"
|
||
|
|
status=0
|