#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (c) 2019 Red Hat Inc.  All Rights Reserved.
#
# FS QA Test 589
#
# Test mount shared subtrees, verify the move semantics:
#
# ---------------------------------------------------------------------------
# |         MOVE MOUNT OPERATION                                            |
# |**************************************************************************
# |source(A)->| shared       |       private  |       slave    | unbindable |
# | dest(B)  |               |                |                |            |
# |   |      |               |                |                |            |
# |   v      |               |                |                |            |
# |**************************************************************************
# |  shared  | shared        |     shared     | shared & slave |  invalid   |
# |          |               |                |                |            |
# |non-shared| shared        |      private   |      slave     | unbindable |
# ***************************************************************************
#   NOTE: moving a mount residing under a shared mount is invalid.
#
#-----------------------------------------------------------------------
#
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.*
	_clear_mount_stack
	# make sure there's no bug cause dentry isn't be freed
	rm -rf $MNTHEAD
}

# 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 generic
_require_test
_require_scratch
_require_local_device $SCRATCH_DEV

fs_stress()
{
	local target=$1

	$FSSTRESS_PROG -n 50 -p 3 -d $target >/dev/null
	sync
}

# prepare some mountpoint dir
SRCHEAD=$TEST_DIR/$seq-src
DSTHEAD=$TEST_DIR/$seq-dst
rm -rf $SRCHEAD $DSTHEAD
mkdir $SRCHEAD $DSTHEAD 2>>$seqres.full
mpA=$SRCHEAD/"$$"_mpA
mpB=$SRCHEAD/"$$"_mpB
mpC=$DSTHEAD/"$$"_mpC
mpD=$DSTHEAD/"$$"_mpD

find_mnt()
{
	echo "------"
	findmnt -n -o TARGET,SOURCE $SCRATCH_DEV | \
		sed -e "s;$mpA;mpA;g" \
		    -e "s;$mpB;mpB;g" \
		    -e "s;$mpC;mpC;g" \
		    -e "s;$mpD;mpD;g" | \
		_filter_spaces | _filter_testdir_and_scratch | sort
	echo "======"
}

start_test()
{
	local type=$1

	_scratch_mkfs >$seqres.full 2>&1

	_get_mount -t $FSTYP $SCRATCH_DEV $SRCHEAD
	# make sure $SRCHEAD is private
	$MOUNT_PROG --make-private $SRCHEAD

	_get_mount -t $FSTYP $SCRATCH_DEV $DSTHEAD
	# test start with a bind, then make-shared $DSTHEAD
	_get_mount --bind $DSTHEAD $DSTHEAD
	$MOUNT_PROG --make-"${type}" $DSTHEAD
	mkdir $mpA $mpB $mpC $mpD
}

end_test()
{
	_clear_mount_stack
	rm -rf $mpA $mpB $mpC $mpD
}

move_run()
{
	local source=$1
	local dest=$2

	start_test $dest

	echo "move $source to $dest"
	_get_mount -t $FSTYP $SCRATCH_DEV $mpA
	mkdir -p $mpA/dir 2>/dev/null
	$MOUNT_PROG --make-shared $mpA
	# need a peer for slave later
	_get_mount --bind $mpA $mpB
	$MOUNT_PROG --make-"$source" $mpB
	# maybe unbindable at here
	_get_mount --move $mpB $mpC 2>/dev/null
	if [ $? -ne 0 ]; then
		find_mnt
		end_test
		return 0
	fi

	# check mpC after move B to C
	for m in $mpA $mpC; do
		_get_mount -t $FSTYP $SCRATCH_DEV $m/dir
		fs_stress $m/dir
		find_mnt
		_put_mount
	done

	# mpC will be in different parent mount, test moving from different
	# parent mount, and moving a mount residing under a shared mount is
	# invalid
	_get_mount --move $mpC $mpD 2>/dev/null
	if [ $? -ne 0 ]; then
		find_mnt
		end_test
		return 0
	fi
	for m in $mpA $mpD; do
		_get_mount -t $FSTYP $SCRATCH_DEV $m/dir
		fs_stress $m/dir
		find_mnt
		_put_mount
	done

	end_test
}

move_test()
{
	#        source     dest
	move_run shared     shared
	move_run slave      shared
	move_run private    shared
	move_run unbindable shared

	move_run shared     slave
	move_run slave      slave
	move_run private    slave
	move_run unbindable slave

	move_run shared     private
	move_run slave      private
	move_run private    private
	move_run unbindable private
}

move_test

# success, all done
status=0
exit