#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2020 SUSE Linux Products GmbH. All Rights Reserved.
#
# FSQA Test No. 209
#
# Test a scenario were we fsync a range of a file and have a power failure.
# We want to check that after a power failure and mounting the filesystem, we
# do not end up with a missing file extent representing a hole. This applies
# only when not using the NO_HOLES feature.
#
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/attr
. ./common/filter
. ./common/dmflakey

# real QA test starts here
_supported_fs btrfs
_supported_os Linux
_require_scratch
_require_dm_target flakey
_require_btrfs_fs_feature "no_holes"
_require_btrfs_mkfs_feature "no-holes"
_require_xfs_io_command "sync_range"

rm -f $seqres.full

_scratch_mkfs -O ^no-holes >>$seqres.full 2>&1
_require_metadata_journaling $SCRATCH_DEV
_init_flakey
_mount_flakey

# Create a 256K file with a single extent and fsync it to clear the full sync
# bit from the inode - we want the msync below to trigger a fast fsync.
$XFS_IO_PROG -f \
	     -c "pwrite -S 0xab 0 256K" \
	     -c "fsync" \
	     $SCRATCH_MNT/foo | _filter_xfs_io

# Force a transaction commit and wipe out the log tree.
sync

# Dirty 768K of data, increasing the file size to 1Mb, and flush only the range
# from 256K to 512K without updating the log tree (sync_file_range() does not
# trigger fsync, it only starts writeback and waits for it to finish).
$XFS_IO_PROG -c "pwrite -S 0xcd 256K 768K" \
	     -c "sync_range -abw 256K 256K" \
	     $SCRATCH_MNT/foo | _filter_xfs_io

# Now dirty the range from 768K to 1M again and sync that range.
$XFS_IO_PROG \
    -c "mmap -w 768K 256K"        \
    -c "mwrite -S 0xef 768K 256K" \
    -c "msync -s 768K 256K"       \
    -c "munmap"                   \
    $SCRATCH_MNT/foo | _filter_xfs_io

echo "File digest before power failure: $(_md5_checksum $SCRATCH_MNT/foo)"

# Simulate a power failure and mount again the filesystem.
_flakey_drop_and_remount

# Should match what we got before the power failure.
echo "File digest after power failure: $(_md5_checksum $SCRATCH_MNT/foo)"

# We also want to check that fsck doesn't fail due to an error of a missing
# file extent item that represents a hole for the range 256K to 512K. The
# fstests framework does the fsck once the test exits.
_unmount_flakey

status=0
exit