#! /bin/bash
# FS QA Test No. btrfs/056
#
# Regression test for btrfs ioctl clone operation + fsync + log recovery.
# The issue was that doing an fsync after cloning into a file didn't gave any
# persistence guarantees as it should. What happened was that the in memory
# metadata (extent maps) weren't updated, which made the fsync code not able
# to detect that file data has been changed.
#
# This issue is fixed by the following linux kernel btrfs patch:
#
#    Btrfs: make fsync work after cloning into a file
#
#-----------------------------------------------------------------------
# Copyright (c) 2014 Filipe Manana.  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"

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

_cleanup()
{
	_cleanup_flakey
	rm -fr $tmp
}

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

# real QA test starts here
_supported_fs btrfs
_supported_os Linux
_require_scratch
_require_cloner
_require_btrfs_fs_feature "no_holes"
_require_btrfs_mkfs_feature "no-holes"
_require_dm_flakey
_need_to_be_root

rm -f $seqres.full

test_btrfs_clone_fsync_log_recover()
{
	_scratch_mkfs "$1" >/dev/null 2>&1
	_init_flakey
	SAVE_MOUNT_OPTIONS="$MOUNT_OPTIONS"
	MOUNT_OPTIONS="$MOUNT_OPTIONS $2"
	_mount_flakey

	# Create a file with 4 extents and 1 hole, all with a size of 8Kb each.
	# The hole is in the range [16384, 24576[.
	$XFS_IO_PROG -s -f -c "pwrite -S 0x01 -b 8192 0 8192" \
			-c "pwrite -S 0x02 -b 8192 8192 8192" \
			-c "pwrite -S 0x04 -b 8192 24576 8192" \
			-c "pwrite -S 0x05 -b 8192 32768 8192" \
		$SCRATCH_MNT/foo | _filter_xfs_io

	# Clone destination file, 1 extent of 96kb.
	$XFS_IO_PROG -f -c "pwrite -S 0xff -b 98304 0 98304" -c "fsync" \
		$SCRATCH_MNT/bar | _filter_xfs_io

	# Clone second half of the 2nd extent, the 8kb hole, the 3rd extent
	# and the first half of the 4th extent into file bar.
	$CLONER_PROG -s 12288 -d 0 -l 24576 $SCRATCH_MNT/foo $SCRATCH_MNT/bar
	$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/bar

	# Test small files too consisting of 1 inline extent
	$XFS_IO_PROG -f -c "pwrite -S 0x00 -b 3500 0 3500" -c "fsync" \
		$SCRATCH_MNT/foo2 | _filter_xfs_io

	$XFS_IO_PROG -f -c "pwrite -S 0xcc -b 1000 0 1000" -c "fsync" \
		$SCRATCH_MNT/bar2 | _filter_xfs_io

	# Clone the entire foo2 file into bar2, overwriting all data in bar2
	# and increasing its size.
	$CLONER_PROG -s 0 -d 0 -l 3500 $SCRATCH_MNT/foo2 $SCRATCH_MNT/bar2
	$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/bar2

	_load_flakey_table $FLAKEY_DROP_WRITES
	_unmount_flakey

	# Verify that there are no consistency errors.
	_check_scratch_fs $FLAKEY_DEV

	_load_flakey_table $FLAKEY_ALLOW_WRITES
	_mount_flakey

	# Verify the cloned range was persisted by fsync and the log recovery
	# code did its work well.
	echo "Verifying file bar content"
	od -t x1 $SCRATCH_MNT/bar

	echo "Verifying file bar2 content"
	od -t x1 $SCRATCH_MNT/bar2

	_unmount_flakey

	# Verify that there are no consistency errors.
	_check_scratch_fs $FLAKEY_DEV

	_cleanup_flakey
	MOUNT_OPTIONS="$SAVE_MOUNT_OPTIONS"
}

# Regardless of the NO_HOLES feature being enabled or not, the test results
# should be exactly the same for both cases.

echo "Testing without the NO_HOLES feature"
# As of btrfs-progs 3.14.x, the no-holes feature isn't enabled by default.
# But explicitly disable it at mkfs time as it might be enabled by default
# in future versions.
test_btrfs_clone_fsync_log_recover "-O ^no-holes"

echo "Testing without the NO_HOLES feature and compression (lzo)"
test_btrfs_clone_fsync_log_recover "-O ^no-holes" "-o compress-force=lzo"

echo "Testing with the NO_HOLES feature enabled"
test_btrfs_clone_fsync_log_recover "-O no-holes"

echo "Testing with the NO_HOLES feature enabled and compression (lzo)"
test_btrfs_clone_fsync_log_recover "-O no-holes" "-o compress-force=lzo"

status=0
exit