#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2022 SUSE Linux Products GmbH. All Rights Reserved.
#
# FS QA Test 257
#
# Make sure btrfs doesn't defrag preallocated extents, nor lone extents
# before preallocated extents.
#

. ./common/preamble
_begin_fstest auto quick defrag prealloc fiemap

# Override the default cleanup function.
# _cleanup()
# {
# 	cd /
# 	rm -r -f $tmp.*
# }

. ./common/filter

_supported_fs btrfs
_require_scratch

# We rely on specific extent layout, don't run on compress
_require_btrfs_no_compress

# Needs 4K sectorsize
_require_btrfs_support_sectorsize 4096
_require_xfs_io_command "falloc"
_require_xfs_io_command "fiemap"

_scratch_mkfs -s 4k >> $seqres.full 2>&1

# Need datacow to make the defragged extents to have different bytenr
_scratch_mount -o datacow

# Create a file with the following layout:
# 0       4K        8K        16K
# |<- R ->|<-- Preallocated ->|
# R is regular extents.
#
# In this case it makes no sense to defrag any extent.
$XFS_IO_PROG -f -c "pwrite 0 4k" -c sync -c "falloc 4k 12k" \
	"$SCRATCH_MNT/foobar" >> $seqres.full

echo "=== Initial file extent layout ===" >> $seqres.full
$XFS_IO_PROG -c "fiemap -v" "$SCRATCH_MNT/foobar" >> $seqres.full

# Save the bytenr of both extents
old_regular=$(_get_file_extent_sector "$SCRATCH_MNT/foobar" 0)
old_prealloc=$(_get_file_extent_sector "$SCRATCH_MNT/foobar" 4096)

# Now defrag and write the defragged range back to disk
$BTRFS_UTIL_PROG filesystem defrag "$SCRATCH_MNT/foobar" >> $seqres.full
sync

echo "=== File extent layout after defrag ===" >> $seqres.full
$XFS_IO_PROG -c "fiemap -v" "$SCRATCH_MNT/foobar" >> $seqres.full

new_regular=$(_get_file_extent_sector "$SCRATCH_MNT/foobar" 0)
new_prealloc=$(_get_file_extent_sector "$SCRATCH_MNT/foobar" 4096)

if [ "$old_regular" -ne "$new_regular" ]; then
	echo "the single lone sector got defragged"
fi
if [ "$old_prealloc" -ne "$new_prealloc" ]; then
	echo "the preallocated extent got defragged"
fi

echo "Silence is golden"

# success, all done
status=0
exit