tests/generic/695

#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2022 SUSE Linux Products GmbH. All Rights Reserved.
#
# FS QA Test 695
#
# Test that if we punch a hole adjacent to an existing hole, fsync the file and
# then power fail, the new hole exists after mounting again the filesystem.
#
# This is motivated by a regression on btrfs, fixed by the commit mentioned
# below, when not using the no-holes feature (which is enabled by default since
# btrfs-progs 5.15).
#
. ./common/preamble
_begin_fstest auto quick log punch fiemap

_cleanup()
{
	_cleanup_flakey
	cd /
	rm -r -f $tmp.*
}

. ./common/filter
. ./common/dmflakey
. ./common/punch

[ "$FSTYP" = "btrfs" ] && _fixed_by_kernel_commit e6e3dec6c3c288 \
        "btrfs: update generation of hole file extent item when merging holes"
_require_scratch
_require_dm_target flakey
_require_xfs_io_command "fpunch"
_require_xfs_io_command "fiemap"

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

# We punch 2M holes and require extent allocations to align to 2M in fiemap
# results.
_require_congruent_file_oplen $SCRATCH_MNT $((2 * 1024 * 1024))

# Create our test file with the following layout:
#
# [0, 2M)    - hole
# [2M, 10M)  - extent
# [10M, 12M) - hole
$XFS_IO_PROG -f -c "truncate 12M" \
	     -c "pwrite -S 0xab 2M 8M" \
	     $SCRATCH_MNT/foobar | _filter_xfs_io

# Persist everything, commit the filesystem's transaction.
_scratch_sync

# Now punch two holes in the file:
#
# 1) For the range [2M, 4M), which is adjacent to the existing hole in the range
#    [0, 2M);
# 2) For the range [8M, 10M), which is adjacent to the existing hole in the
#    range [10M, 12M).
#
# These operations start a new filesystem transaction.
# Then finally fsync the file.
$XFS_IO_PROG -c "fpunch 2M 2M" \
	     -c "fpunch 8M 2M" \
	     -c "fsync" $SCRATCH_MNT/foobar

# Simulate a power failure and mount the filesystem to check that everything
# is in the same state as before the power failure.
_flakey_drop_and_remount

# We expect the following file layout:
#
# [0, 4M)    - hole
# [4M, 8M)   - extent
# [8M, 12M)  - hole
echo "File layout after power failure:"
$XFS_IO_PROG -c "fiemap -v" $SCRATCH_MNT/foobar | _filter_fiemap

# When reading the file we expect to get the range [4M, 8M) filled with bytes
# that have a value of 0xab and 0x00 for anything outside that range.
echo "File content after power failure:"
_hexdump $SCRATCH_MNT/foobar

_unmount_flakey

# success, all done
status=0
exit