2 # SPDX-License-Identifier: GPL-2.0
3 # Copyright (c) 2017 Oracle. All Rights Reserved.
7 # The test case is to reproduce a bug in raid6 reconstruction process that
8 # would end up with read failure if there is data corruption on two disks in
9 # the same horizontal stripe, e.g. due to bitrot.
11 # The bug happens when
12 # a) all disks are good to read,
13 # b) there is corrupted data on two disks in the same horizontal stripe due to
14 # something like bitrot,
15 # c) when rebuilding data after crc fails, btrfs is not able to tell whether
16 # other copies are good or corrupted because btrfs doesn't have crc for
19 # The kernel fixes are
20 # Btrfs: do not merge rbios if their fail stripe index are not identical
21 # Btrfs: make raid6 rebuild retry more
24 _begin_fstest auto quick raid read_repair
26 # Import common functions.
29 # real QA test starts here
31 # Modify as appropriate.
33 _require_scratch_dev_pool 4
34 _require_btrfs_command inspect-internal dump-tree
35 _require_btrfs_fs_feature raid56
40 $BTRFS_UTIL_PROG inspect-internal dump-tree -t 3 $SCRATCH_DEV | \
41 grep " DATA\|RAID6" -A 10 | \
42 $AWK_PROG "(\$1 ~ /stripe/ && \$3 ~ /devid/ && \$2 ~ /$stripe/) { print \$6 }"
48 $BTRFS_UTIL_PROG inspect-internal dump-tree -t 3 $SCRATCH_DEV | \
49 grep " DATA\|RAID6" -A 10 | \
50 $AWK_PROG "(\$1 ~ /stripe/ && \$3 ~ /devid/ && \$2 ~ /$stripe/) { print \$4 }"
56 echo "$SCRATCH_DEV_POOL" | $AWK_PROG "{print \$$devid}"
59 _scratch_dev_pool_get 4
60 # step 1: create a raid6 btrfs and create a 128K file
61 echo "step 1......mkfs.btrfs" >>$seqres.full
63 _check_minimal_fs_size $(( 1024 * 1024 * 1024 ))
64 mkfs_opts="-d raid6 -b 1G"
65 _scratch_pool_mkfs $mkfs_opts >>$seqres.full 2>&1
67 # make sure data is written to the start position of the data chunk
68 _scratch_mount $(_btrfs_no_v1_cache_opt)
70 # [0,64K) is written to stripe 0 and [64K, 128K) is written to stripe 1
71 $XFS_IO_PROG -f -d -c "pwrite -S 0xaa 0 128K" -c "fsync" \
72 "$SCRATCH_MNT/foobar" | _filter_xfs_io
74 logical=$(_btrfs_get_first_logical $SCRATCH_MNT/foobar)
77 phy0=$(get_physical 0)
79 devpath0=$(get_device_path $devid0)
80 phy1=$(get_physical 1)
82 devpath1=$(get_device_path $devid1)
84 # step 2: corrupt stripe #0 and #1
85 echo "step 2......simulate bitrot at:" >>$seqres.full
86 echo " ......stripe #0: devid $devid0 devpath $devpath0 phy $phy0" \
88 echo " ......stripe #1: devid $devid1 devpath $devpath1 phy $phy1" \
91 $XFS_IO_PROG -f -d -c "pwrite -S 0xbb $phy0 64K" $devpath0 > /dev/null
92 $XFS_IO_PROG -f -d -c "pwrite -S 0xbb $phy1 64K" $devpath1 > /dev/null
94 # step 3: read foobar to repair the bitrot
95 echo "step 3......repair the bitrot" >> $seqres.full
96 _scratch_mount $(_btrfs_no_v1_cache_opt)
98 # read the 2nd stripe, i.e. [64K, 128K), to trigger repair
99 od -x -j 64K $SCRATCH_MNT/foobar
101 _scratch_dev_pool_put