#!/bin/bash
# FS QA Test No. xfs/011
#
# Test the xfs log reservation mechanism for leaks. Run an fsstress workload to
# include a variety of fs operations, freeze the filesystem and verify that
# there are no oustanding reservations against the log.
#
#-----------------------------------------------------------------------
# Copyright (c) 2014 Red Hat, 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!

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

_cleanup()
{
	$KILLALL_PROG -9 fsstress 2>/dev/null
	wait
	cd /
	_scratch_unmount 2>/dev/null
	rm -f $tmp.*
}
trap "_cleanup; exit \$status" 0 1 2 3 15

# Use the information exported by XFS to sysfs to determine whether the log has
# active reservations after a filesystem freeze.
_check_scratch_log_state()
{
	devname=`_short_dev $SCRATCH_DEV`
	attrpath="/sys/fs/xfs/$devname/log"

	# freeze the fs to ensure data is synced and the log is flushed. this
	# means no outstanding transactions, and thus no outstanding log
	# reservations, should exist
	xfs_freeze -f $SCRATCH_MNT

	# the log head is exported in basic blocks and the log grant heads in
	# bytes. convert the log head to bytes for precise comparison
	log_head_cycle=`awk -F : '{ print $1 }' $attrpath/log_head_lsn`
	log_head_bytes=`awk -F : '{ print $2 }' $attrpath/log_head_lsn`
	log_head_bytes=$((log_head_bytes * 512))

	for attr in "reserve_grant_head" "write_grant_head"; do
		cycle=`cat $attrpath/$attr | awk -F : '{ print $1 }'`
		bytes=`cat $attrpath/$attr | awk -F : '{ print $2 }'`

		if [ $cycle != $log_head_cycle ] ||
		   [ $bytes != $log_head_bytes ]
		then
			echo "$attr ($cycle:$bytes) does not match" \
				"log_head_lsn ($log_head_cycle:$log_head_bytes)," \
				"possible leak detected."
		fi
	done

	xfs_freeze -u $SCRATCH_MNT
}

# real QA test starts here
_supported_fs xfs
_supported_os Linux

_require_scratch
_require_freeze
_require_xfs_sysfs $(_short_dev $TEST_DEV)/log
_require_command "$KILLALL_PROG" killall

rm -f $seqres.full

echo "Silence is golden."

_scratch_mkfs_xfs >> $seqres.full 2>&1
_scratch_mount

_check_scratch_log_state

$FSSTRESS_PROG -d $SCRATCH_MNT/fsstress -n 9999999 -p 2 -S t \
	>> $seqres.full 2>&1 &

iters=5
while [ $iters -gt 0 ]; do
	sleep 3
	_check_scratch_log_state
	iters=$((iters - 1))
done

$KILLALL_PROG $FSSTRESS_PROG
wait

_scratch_unmount

status=0
exit
