#! /bin/bash
# FSQA Test No. 017
#
# Test unstable inode number
#
# This simple test demonstrates a known issue with overlayfs:
# - stat file A shows inode number X
# - modify A to trigger copy up
# - stat file A shows inode number Y != X
#
# Also test if d_ino of readdir entries changes after copy up.
#
#-----------------------------------------------------------------------
#
# Copyright (C) 2016 CTERA Networks. All Rights Reserved.
# Author: Amir Goldstein <amir73il@gmail.com>
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it would be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write the Free Software Foundation,
# Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
#-----------------------------------------------------------------------
#

seq=`basename $0`
seqres=$RESULT_DIR/$seq
echo "QA output created by $seq"

tmp=/tmp/$$
status=1	# failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 15

_cleanup()
{
	rm -f $tmp.*
}

# get standard environment, filters and checks
. ./common/rc
. ./common/filter

# real QA test starts here
_supported_fs overlay
_supported_os Linux
_require_scratch

rm -f $seqres.full

_scratch_mkfs >>$seqres.full 2>&1

# Create our test files.
# Not dealing with hardlinks here, because there is more to test
# then stable inode number.
# Hardlinks will get a test of their own.
lowerdir=$SCRATCH_DEV/$OVERLAY_LOWER_DIR
mkdir -p $lowerdir
mkdir $lowerdir/dir
touch $lowerdir/file
ln -s $lowerdir/file $lowerdir/symlink
mknod $lowerdir/chrdev c 1 1
mknod $lowerdir/blkdev b 1 1
mknod $lowerdir/fifo p


_scratch_mount


rm -f $tmp.before $tmp.after

# Test stable stat(2) st_ino

# Record inode numbers before and after copy up
for f in dir file symlink chrdev blkdev fifo; do
	ls -id $SCRATCH_MNT/$f >> $tmp.before
	# chown -h modifies all those file types
	chown -h 100 $SCRATCH_MNT/$f
	ls -id $SCRATCH_MNT/$f >> $tmp.after
done

# Test stable readdir(3)/getdents(2) d_ino

# find by inode number - expect to find file by inode number
cat $tmp.before | while read ino f; do
	find $f -inum $ino -maxdepth 0 | _filter_scratch
done

# Compare before..after - expect silence
diff $tmp.before $tmp.after

status=0
exit