2 # SPDX-License-Identifier: GPL-2.0
3 # Copyright (c) 2016 Red Hat, Inc. All Rights Reserved.
7 # Regression test for an XFS multi-block buffer logging bug.
9 # The XFS bug results in a panic when a non-contiguous multi-block buffer is
10 # mapped and logged in a particular manner, such that only regions beyond the
11 # first fsb-sized mapping are logged. The crash occurs asynchronous to
12 # transaction submission, when the associated buffer log item is pushed from the
13 # CIL (i.e., when the log is subsequently flushed).
16 seqres=$RESULT_DIR/$seq
17 echo "QA output created by $seq"
21 status=1 # failure is the default!
22 trap "_cleanup; exit \$status" 0 1 2 3 15
30 # get standard environment, filters and checks
33 # Modify as appropriate.
37 _require_scratch_nocheck # check complains about single AG fs
39 _require_xfs_io_command "fpunch"
40 _require_command $UUIDGEN_PROG uuidgen
44 # Create a small fs with a large directory block size. We want to fill up the fs
45 # quickly and then create multi-fsb dirblocks over fragmented free space.
46 _scratch_mkfs_xfs -d size=20m -n size=64k >> $seqres.full 2>&1
49 # Fill a source directory with many largish-named files. 1k uuid-named entries
50 # sufficiently populates a 64k directory block.
51 mkdir $SCRATCH_MNT/src
52 for i in $(seq 0 1023); do
53 touch $SCRATCH_MNT/src/`$UUIDGEN_PROG`
56 # precreate target dirs while we still have free space for inodes
57 for i in $(seq 0 3); do
61 # consume and fragment free space
62 $XFS_IO_PROG -xc "resblks 16" $SCRATCH_MNT >> $seqres.full 2>&1
63 dd if=/dev/zero of=$SCRATCH_MNT/file bs=4k >> $seqres.full 2>&1
64 $XFS_IO_PROG -c "fsync" $SCRATCH_MNT/file >> $seqres.full 2>&1
65 size=`_get_filesize $SCRATCH_MNT/file`
66 for i in $(seq 0 8192 $size); do
67 $XFS_IO_PROG -c "fpunch $i 4k" $SCRATCH_MNT/file >> $seqres.full 2>&1
70 # Replicate the src dir several times into fragmented free space. After one or
71 # two dirs, we should have nothing but non-contiguous directory blocks.
72 for d in $(seq 0 3); do
73 for f in `ls -1 $SCRATCH_MNT/src`; do
74 ln $SCRATCH_MNT/src/$f $SCRATCH_MNT/$d/$f
78 # Fragment the target dirs a bit. Remove a handful of entries from each to
79 # populate the best free space regions in the directory block headers. We want
80 # to populate these now so the subsequent unlinks have no reason to log the
81 # first block of the directory.
82 for d in $(seq 0 3); do
84 for f in `ls -U $SCRATCH_MNT/$d`; do
86 unlink $SCRATCH_MNT/$d/$f
92 # remount to flush and ensure subsequent operations allocate a new log item
95 # Unlink an entry towards the end of each dir and fsync. The unlink should only
96 # need to log the latter mappings of the 64k directory block. If the logging bug
97 # is present, this will crash!
98 for d in $(seq 0 3); do
99 f=`ls -U $SCRATCH_MNT/$d | tail -10 | head -n 1`
100 unlink $SCRATCH_MNT/$d/$f
101 $XFS_IO_PROG -c fsync $SCRATCH_MNT/$d
104 echo Silence is golden.