#! /bin/bash
# FS QA Test No. 166
#
# Test for races or FS corruption when DIO writing to a file that's also
# the source of a reflink operation.
#
#-----------------------------------------------------------------------
# Copyright (c) 2015 Oracle, Inc.  All Rights Reserved.
#
# 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"

here=`pwd`
tmp=/tmp/$$
status=1	# failure is the default!
trap "_cleanup; exit \$status" 0 1 2 3 7 15

_cleanup()
{
    cd /
    rm -rf "$tmp".*
    wait
}

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

# real QA test starts here
_supported_os Linux
_require_scratch_reflink
_require_cp_reflink

echo "Format and mount"
_scratch_mkfs > "$seqres.full" 2>&1
_scratch_mount >> "$seqres.full" 2>&1

testdir="$SCRATCH_MNT/test-$seq"
rm -rf "$testdir"
mkdir "$testdir"

loops=1024
nr_loops=$((loops - 1))
blksz=65536

echo "Initialize file"
echo > "$seqres.full"
_pwrite_byte 0x61 0 $((loops * blksz)) "$testdir/file1" >> "$seqres.full"
_scratch_remount

# Snapshot creator...
snappy() {
	n=0
	while [ ! -e "$testdir/finished" ]; do
		_cp_reflink "$testdir/file1" "$testdir/snap_$n" || break
		n=$((n + 1))
	done
}

echo "Snapshot a file undergoing directio rewrite"
snappy &
seq $nr_loops -1 0 | while read i; do
	_pwrite_byte 0x63 $((i * blksz)) $blksz -d "$testdir/file1" >> "$seqres.full"
done
touch $testdir/finished
wait

echo "Check for damage"
_scratch_unmount
_check_scratch_fs

echo "Done"

# success, all done
status=0
exit