#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (c) 2017 Red Hat Inc.  All Rights Reserved.
#
# FS QA Test 029
#
# There are dirs/files in lower dir and upper dir before
# mounting overlayfs. After mounting, use dir in overlayfs
# mountpoint as lowerdir to mount another overlayfs, then
# access old files through the second overlayfs. It was
# not working, kernel commit below fixed it.
#
# c4fcfc1619ea ovl: fix d_real() for stacked fs
#
# This reproducer was originally written by
#     Miklos Szeredi <mszeredi@redhat.com>
#
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 /
	$UMOUNT_PROG $tmp/mnt
	rm -rf $tmp
	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

# Modify as appropriate.
_supported_fs overlay
_require_scratch

# Remove all files from previous tests
_scratch_mkfs

# Preparing files
upperdir=$OVL_BASE_SCRATCH_MNT/$OVL_UPPER
lowerdir=$OVL_BASE_SCRATCH_MNT/$OVL_LOWER
mkdir -p $upperdir/up
echo foo > $upperdir/up/foo
mkdir -p $lowerdir/low
echo bar > $lowerdir/low/bar

# mount overlay in SCRATCH_MNT
_scratch_mount

mkdir -p $tmp/{upper,mnt,work}
# mount overlay again using upper dir from SCRATCH_MNT dir
_overlay_mount_dirs $SCRATCH_MNT/up $tmp/{upper,work} \
  overlay $tmp/mnt
# accessing file in the second mount
cat $tmp/mnt/foo
$UMOUNT_PROG $tmp/mnt

# re-create upper/work to avoid ovl_verify_origin() mount failure
# when index is enabled
rm -rf $tmp/{upper,work}
mkdir -p $tmp/{upper,work}
# mount overlay again using lower dir from SCRATCH_MNT dir
_overlay_mount_dirs $SCRATCH_MNT/low $tmp/{upper,work} \
  overlay $tmp/mnt
cat $tmp/mnt/bar
$UMOUNT_PROG $tmp/mnt

rm -rf $tmp/{upper,work}
mkdir -p $tmp/{upper,work}
# mount overlay again using SCRATCH_MNT dir
_overlay_mount_dirs $SCRATCH_MNT/ $tmp/{upper,work} \
  overlay $tmp/mnt
cat $tmp/mnt/up/foo
cat $tmp/mnt/low/bar

# success, all done
status=0
exit