#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2016 SUSE Linux Products GmbH. All Rights Reserved.
#
# FS QA Test 002
#
# Test that calling fsync against a file using the merged directory does not
# result in a crash nor fails unexpectedly.
#
# This is motivated by a change in overlayfs that resulted in a crash (invalid
# memory access) when the lower or upper directory belonged to a btrfs file
# system.
#
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
_supported_fs overlay
_supported_os Linux
_require_scratch

# Remove all files from previous tests
_scratch_mkfs

# Create our test file.
lowerdir=$OVL_BASE_SCRATCH_MNT/$OVL_LOWER
mkdir -p $lowerdir
touch $lowerdir/foobar

_scratch_mount

# Write some data to our file and fsync it, using the merged directory path.
# This should work and not result in a crash.
$XFS_IO_PROG -c "pwrite 0 64k" -c "fsync" $SCRATCH_MNT/foobar | _filter_xfs_io

# success, all done
status=0
exit