From 65d01862c82d46a2f440dab3818e8e08e6879551 Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Sat, 13 Jun 2015 16:22:34 +0200 Subject: [PATCH 40/42] iotests: Add tests for refcount table growth Message-id: <1434212556-3927-41-git-send-email-mreitz@redhat.com> Patchwork-id: 66059 O-Subject: [RHEL-7.2 qemu-kvm PATCH 40/42] iotests: Add tests for refcount table growth Bugzilla: 1129893 RH-Acked-by: Jeffrey Cody RH-Acked-by: Fam Zheng RH-Acked-by: Stefan Hajnoczi BZ: 1129893 Signed-off-by: Max Reitz Message-id: 1423598552-24301-3-git-send-email-mreitz@redhat.com Reviewed-by: Eric Blake Reviewed-by: Kevin Wolf Signed-off-by: Max Reitz (cherry picked from commit 0e8a371468ce24513b15a9ae362f12822e1973a3) Signed-off-by: Miroslav Rezanina Conflicts: tests/qemu-iotests/group Signed-off-by: Max Reitz --- tests/qemu-iotests/121 | 102 +++++++++++++++++++++++++++++++++++++++++++++ tests/qemu-iotests/121.out | 23 ++++++++++ tests/qemu-iotests/group | 1 + 3 files changed, 126 insertions(+) create mode 100755 tests/qemu-iotests/121 create mode 100644 tests/qemu-iotests/121.out diff --git a/tests/qemu-iotests/121 b/tests/qemu-iotests/121 new file mode 100755 index 0000000..0912c3f --- /dev/null +++ b/tests/qemu-iotests/121 @@ -0,0 +1,102 @@ +#!/bin/bash +# +# Test cases for qcow2 refcount table growth +# +# Copyright (C) 2015 Red Hat, Inc. +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . +# + +# creator +owner=mreitz@redhat.com + +seq="$(basename $0)" +echo "QA output created by $seq" + +here="$PWD" +tmp=/tmp/$$ +status=1 # failure is the default! + +_cleanup() +{ + _cleanup_test_img +} +trap "_cleanup; exit \$status" 0 1 2 3 15 + +# get standard environment, filters and checks +. ./common.rc +. ./common.filter + +_supported_fmt qcow2 +_supported_proto file +_supported_os Linux + +echo +echo '=== New refcount structures may not conflict with existing structures ===' + +echo +echo '--- Test 1 ---' +echo + +# Preallocation speeds up the write operation, but preallocating everything will +# destroy the purpose of the write; so preallocate one KB less than what would +# cause a reftable growth... +IMGOPTS='preallocation=metadata,cluster_size=1k' _make_test_img 64512K +# ...and make the image the desired size afterwards. +$QEMU_IMG resize "$TEST_IMG" 65M + +# The first write results in a growth of the refcount table during an allocation +# which has precisely the required size so that the new refcount block allocated +# in alloc_refcount_block() is right after cluster_index; this did lead to a +# different refcount block being written to disk (a zeroed cluster) than what is +# cached (a refblock with one entry having a refcount of 1), and the second +# write would then result in that cached cluster being marked dirty and then +# in it being written to disk. +# This should not happen, the new refcount structures may not conflict with +# new_block. +# (Note that for some reason, 'write 63M 1K' does not trigger the problem) +$QEMU_IO -c 'write 62M 1025K' -c 'write 64M 1M' "$TEST_IMG" | _filter_qemu_io + +_check_test_img + + +echo +echo '--- Test 2 ---' +echo + +IMGOPTS='preallocation=metadata,cluster_size=1k' _make_test_img 64513K +# This results in an L1 table growth which in turn results in some clusters at +# the start of the image becoming free +$QEMU_IMG resize "$TEST_IMG" 65M + +# This write results in a refcount table growth; but the refblock allocated +# immediately before that (new_block) takes cluster index 4 (which is now free) +# and is thus not self-describing (in contrast to test 1, where new_block was +# self-describing). The refcount table growth algorithm then used to place the +# new refcount structures at cluster index 65536 (which is the same as the +# cluster_index parameter in this case), allocating a new refcount block for +# that cluster while new_block already existed, leaking new_block. +# Therefore, the new refcount structures may not be put at cluster_index +# (because new_block already describes that cluster, and the new structures try +# to be self-describing). +$QEMU_IO -c 'write 63M 130K' "$TEST_IMG" | _filter_qemu_io + +_check_test_img + + +# success, all done +echo +echo '*** done' +rm -f $seq.full +status=0 diff --git a/tests/qemu-iotests/121.out b/tests/qemu-iotests/121.out new file mode 100644 index 0000000..ff18e2c --- /dev/null +++ b/tests/qemu-iotests/121.out @@ -0,0 +1,23 @@ +QA output created by 121 + +=== New refcount structures may not conflict with existing structures === + +--- Test 1 --- + +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=66060288 preallocation='metadata' +Image resized. +wrote 1049600/1049600 bytes at offset 65011712 +1.001 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 1048576/1048576 bytes at offset 67108864 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +No errors were found on the image. + +--- Test 2 --- + +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=66061312 preallocation='metadata' +Image resized. +wrote 133120/133120 bytes at offset 66060288 +130 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +No errors were found on the image. + +*** done diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group index 5867cf7..dbb2a36 100644 --- a/tests/qemu-iotests/group +++ b/tests/qemu-iotests/group @@ -89,3 +89,4 @@ 107 rw auto quick 108 rw auto quick 114 rw auto quick +121 rw auto -- 1.8.3.1