tests/generic/177

#! /bin/bash
# FSQA Test No. 177
#
# Test that a file fsync works after punching a hole for the same file range
# multiple times and that after log/journal replay the file's content is
# correct.
#
# This test is motivated by a bug found in btrfs.
#
#-----------------------------------------------------------------------
#
# Copyright (C) 2015 SUSE Linux Products GmbH. All Rights Reserved.
# Author: Filipe Manana <fdmanana@suse.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()
{
	_cleanup_flakey
	cd /
	rm -f $tmp.*
}

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

# real QA test starts here
_supported_fs generic
_supported_os Linux
_require_scratch
_require_xfs_io_command "fpunch"
_require_xfs_io_command "fiemap"
_require_dm_target flakey

rm -f $seqres.full

_scratch_mkfs >>$seqres.full 2>&1
_require_metadata_journaling $SCRATCH_DEV
_init_flakey
_mount_flakey

# Create out test file with some data and then fsync it.
# We do the fsync only to make sure the last fsync we do in this test triggers
# the fast code path of btrfs' fsync implementation, a condition necessary to
# trigger the bug btrfs had.
$XFS_IO_PROG -f -c "pwrite -S 0xaa 0K 128K" \
		-c "fsync"                  \
		$SCRATCH_MNT/foobar | _filter_xfs_io

# Now punch a hole against the range [96K, 128K[.
$XFS_IO_PROG -c "fpunch 96K 32K" $SCRATCH_MNT/foobar

# Punch another hole against a range that overlaps the previous range and ends
# beyond eof.
$XFS_IO_PROG -c "fpunch 64K 128K" $SCRATCH_MNT/foobar

# Punch another hole against a range that overlaps the first range ([96K, 128K[)
# and ends at eof.
$XFS_IO_PROG -c "fpunch 32K 96K" $SCRATCH_MNT/foobar

# Fsync our file. We want to verify that, after a power failure and mounting the
# filesystem again, the file content reflects all the hole punch operations.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foobar

echo "File digest before power failure:"
md5sum $SCRATCH_MNT/foobar | _filter_scratch

echo "Fiemap before power failure:"
$XFS_IO_PROG -c "fiemap -v" $SCRATCH_MNT/foobar | _filter_fiemap

_flakey_drop_and_remount

echo "File digest after log replay:"
# Must match the same digest we got before the power failure.
md5sum $SCRATCH_MNT/foobar | _filter_scratch

echo "Fiemap after log replay:"
# Must match the same extent listing we got before the power failure.
$XFS_IO_PROG -c "fiemap -v" $SCRATCH_MNT/foobar | _filter_fiemap

_unmount_flakey

status=0
exit