#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (c) 2015 Red Hat Inc.  All Rights Reserved.
#
# FS QA Test No. 084
#
# Test hardlink to unlinked file.
#
# Regression test for commit:
# aae8a97 fs: Don't allow to create hardlink for deleted file
#
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

# real QA test starts here
_supported_fs generic
_supported_os Linux
_require_scratch

link_unlink_storm()
{
	local src=$1
	local target=$2
	local i=0

	while true; do
		ln -f $src $target.$i >/dev/null 2>&1
		rm -f $target.$i >/dev/null 2>&1
		let i=i+1
	done
}

rm -f $seqres.full
nr_cpu=`$here/src/feature -o`
echo "Silence is golden"

_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount

# create, open & unlinked files so unlinked inode list is not empty
src/multi_open_unlink -f $SCRATCH_MNT/$seq.unlinked -n $nr_cpu &
open_pid=$!

# start link/unlink storm
src=$SCRATCH_MNT/$seq.target
touch $src
for i in `seq 1 $nr_cpu`; do
	target=$SCRATCH_MNT/$seq.target.link.$i
	link_unlink_storm $src $target &
	link_pids="$link_pids $!"
done

# remove & re-create target to race with link/unlink
while true; do
	rm -f $src
	touch $src
done &
sleep 5
kill $! >/dev/null 2>&1

kill $open_pid $link_pids >/dev/null 2>&1
wait $open_pid $link_pids

# all done, no oops/hang expected, _check_filesystems checks SCRATCH_DEV after test
status=0
exit
