#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (c) 2015 Red Hat Inc. All Rights Reserved.
#
# FS QA Test No. 085
#
# Exercise fs freeze/unfreeze and mount/umount race, which could lead to
# use-after-free oops.
#
# This commit fixed the issue:
# 1494583 fix get_active_super()/umount() race
#
. ./common/preamble
_begin_fstest auto freeze mount

# Override the default cleanup function.
_cleanup()
{
	cleanup_dmdev
	cd /
	rm -f $tmp.*
}

cleanup_dmdev()
{
	if [ -n "$pid" ]; then
		kill -9 $pid 2>> $seqres.full
		wait $pid 2>> $seqres.full
	fi
	# in case it's still suspended and/or mounted
	$DMSETUP_PROG resume $lvdev >> $seqres.full 2>&1
	_unmount -q $SCRATCH_MNT >/dev/null 2>&1
	_dmsetup_remove $node
}

# Import common functions.
. ./common/filter

_require_scratch
_require_block_device $SCRATCH_DEV
_require_dm_target linear
_require_freeze

setup_dmdev()
{
	table="0 $size_in_sector linear $SCRATCH_DEV 0"
	_dmsetup_create $node --table "$table" || \
		_fail "setup dm device failed"
}

echo "Silence is golden"

size=$((256 * 1024 * 1024))
size_in_sector=$((size / 512))
_scratch_mkfs_sized $size >>$seqres.full 2>&1

node=$seq-test
lvdev=/dev/mapper/$node
setup_dmdev

# take use of dmsetup suspend to freeze the fs.
# xfs_freeze/fsfreeze cannot be used in this test, because it can possibly
# freeze the root fs of the host when SCRATCH_MNT is not mounted
#
# And the results of the racing commands (suspend/resume, mount/umount) are not
# important, as long as they're racing with each other. So just throw away the
# outputs and ignore the results.
for ((i=0; i<100; i++)); do
	$DMSETUP_PROG suspend $lvdev >> $seqres.full 2>&1
	$DMSETUP_PROG resume $lvdev >> $seqres.full 2>&1
done &
pid=$!
for ((i=0; i<100; i++)); do
	_mount $lvdev $SCRATCH_MNT >> $seqres.full 2>&1
	_unmount $lvdev >> $seqres.full 2>&1
done &
pid="$pid $!"

wait $pid
unset pid

cleanup_dmdev
status=0
exit
