From 0920e161034a5674a1de8fbdbb505f08c89e10d7 Mon Sep 17 00:00:00 2001 From: Liu Bo Date: Mon, 4 Dec 2017 15:33:23 -0700 Subject: [PATCH] btrfs: reproduce a read failure on raid6 setup This test case is to reproduce a bug of raid6 reconstruction process. The kernel fix are Btrfs: do not merge rbios if their fail stripe index are not identical Btrfs: make raid6 rebuild retry more [eguan: whitespace and indention fix, add 'raid' group] Signed-off-by: Liu Bo Reviewed-by: Eryu Guan Signed-off-by: Eryu Guan --- tests/btrfs/157 | 121 ++++++++++++++++++++++++++++++++++++++++++++ tests/btrfs/157.out | 10 ++++ tests/btrfs/group | 1 + 3 files changed, 132 insertions(+) create mode 100755 tests/btrfs/157 create mode 100644 tests/btrfs/157.out diff --git a/tests/btrfs/157 b/tests/btrfs/157 new file mode 100755 index 00000000..1105253c --- /dev/null +++ b/tests/btrfs/157 @@ -0,0 +1,121 @@ +#! /bin/bash +# FS QA Test 157 +# +# The test case is to reproduce a bug in raid6 reconstruction process that +# would end up with read failure if there is data corruption on two disks in +# the same horizontal stripe, e.g. due to bitrot. +# +# The bug happens when +# a) all disks are good to read, +# b) there is corrupted data on two disks in the same horizontal stripe due to +# something like bitrot, +# c) when rebuilding data after crc fails, btrfs is not able to tell whether +# other copies are good or corrupted because btrfs doesn't have crc for +# unallocated blocks. +# +# The kernel fixes are +# Btrfs: do not merge rbios if their fail stripe index are not identical +# Btrfs: make raid6 rebuild retry more +# +#----------------------------------------------------------------------- +# Copyright (c) 2017 Oracle. All Rights Reserved. +# +# 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. +# +# This program is distributed in the hope that it would 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, write the Free Software Foundation, +# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +#----------------------------------------------------------------------- +# + +seq=`basename $0` +seqres=$RESULT_DIR/$seq +echo "QA output created by $seq" + +here=`pwd` +tmp=/tmp/$$ +status=1 # failure is the default! +trap "_cleanup; exit \$status" 0 1 2 3 15 + +_cleanup() +{ + cd / + rm -f $tmp.* +} + +# get standard environment, filters and checks +. ./common/rc +. ./common/filter + +# remove previous $seqres.full before test +rm -f $seqres.full + +# real QA test starts here + +# Modify as appropriate. +_supported_fs btrfs +_supported_os Linux +_require_scratch_dev_pool 4 +_require_btrfs_command inspect-internal dump-tree + +get_physical_stripe0() +{ + $BTRFS_UTIL_PROG inspect-internal dump-tree -t 3 $SCRATCH_DEV | \ + grep " DATA\|RAID6" -A 10 | \ + $AWK_PROG '($1 ~ /stripe/ && $3 ~ /devid/ && $2 ~ /0/) { print $6 }' +} + +get_physical_stripe1() +{ + $BTRFS_UTIL_PROG inspect-internal dump-tree -t 3 $SCRATCH_DEV | \ + grep " DATA\|RAID6" -A 10 | \ + $AWK_PROG '($1 ~ /stripe/ && $3 ~ /devid/ && $2 ~ /1/) { print $6 }' +} + +_scratch_dev_pool_get 4 +# step 1: create a raid6 btrfs and create a 4K file +echo "step 1......mkfs.btrfs" >>$seqres.full + +mkfs_opts="-d raid6 -b 1G" +_scratch_pool_mkfs $mkfs_opts >>$seqres.full 2>&1 + +# -o nospace_cache makes sure data is written to the start position of the data +# chunk +_scratch_mount -o nospace_cache + +# [0,64K) is written to stripe 0 and [64K, 128K) is written to stripe 1 +$XFS_IO_PROG -f -d -c "pwrite -S 0xaa 0 128K" -c "fsync" \ + "$SCRATCH_MNT/foobar" | _filter_xfs_io + +_scratch_unmount + +stripe_0=`get_physical_stripe0` +stripe_1=`get_physical_stripe1` +dev4=`echo $SCRATCH_DEV_POOL | awk '{print $4}'` +dev3=`echo $SCRATCH_DEV_POOL | awk '{print $3}'` + +# step 2: corrupt the 1st and 2nd stripe (stripe 0 and 1) +echo "step 2......simulate bitrot at offset $stripe_0 of device_4($dev4) and offset $stripe_1 of device_3($dev3)" >>$seqres.full + +$XFS_IO_PROG -f -d -c "pwrite -S 0xbb $stripe_0 64K" $dev4 | _filter_xfs_io +$XFS_IO_PROG -f -d -c "pwrite -S 0xbb $stripe_1 64K" $dev3 | _filter_xfs_io + +# step 3: read foobar to repair the bitrot +echo "step 3......repair the bitrot" >> $seqres.full +_scratch_mount -o nospace_cache + +# read the 2nd stripe, i.e. [64K, 128K), to trigger repair +od -x -j 64K $SCRATCH_MNT/foobar + +_scratch_dev_pool_put + +# success, all done +status=0 +exit diff --git a/tests/btrfs/157.out b/tests/btrfs/157.out new file mode 100644 index 00000000..08d592c4 --- /dev/null +++ b/tests/btrfs/157.out @@ -0,0 +1,10 @@ +QA output created by 157 +wrote 131072/131072 bytes at offset 0 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 65536/65536 bytes at offset 9437184 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 65536/65536 bytes at offset 9437184 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +0200000 aaaa aaaa aaaa aaaa aaaa aaaa aaaa aaaa +* +0400000 diff --git a/tests/btrfs/group b/tests/btrfs/group index ff070d18..f68abf4d 100644 --- a/tests/btrfs/group +++ b/tests/btrfs/group @@ -159,3 +159,4 @@ 154 auto quick 155 auto quick send 156 auto quick trim +157 auto quick raid -- 2.30.2