tests/btrfs/279

#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2022 SUSE Linux Products GmbH. All Rights Reserved.
#
# FS QA Test 279
#
# Test that if we have two files with shared extents, after removing one of the
# files, if we do a fiemap against the other file, it does not report extents as
# shared anymore.
#
# This exercises the processing of delayed references for data extents in the
# backref walking code, used by fiemap to determine if an extent is shared.
#
. ./common/preamble
_begin_fstest auto quick subvol fiemap clone

. ./common/filter
. ./common/reflink
. ./common/punch # for _filter_fiemap_flags

_require_scratch_reflink
_require_cp_reflink
_require_xfs_io_command "fiemap"

_fixed_by_kernel_commit 4fc7b5722824 \
	"btrfs: fix processing of delayed data refs during backref walking"

run_test()
{
	local file_path_1=$1
	local file_path_2=$2
	local do_sync=$3

	$XFS_IO_PROG -f -c "pwrite 0 64K" $file_path_1 | _filter_xfs_io
	_cp_reflink $file_path_1 $file_path_2

	if [ $do_sync -eq 1 ]; then
		sync
	fi

	echo "Fiemap of $file_path_1 before deleting $file_path_2:" | \
		_filter_scratch
	$XFS_IO_PROG -c "fiemap -v" $file_path_1 | _filter_fiemap_flags

	rm -f $file_path_2

	echo "Fiemap of $file_path_1 after deleting $file_path_2:" | \
		_filter_scratch
	$XFS_IO_PROG -c "fiemap -v" $file_path_1 | _filter_fiemap_flags
}

_scratch_mkfs >> $seqres.full 2>&1
_scratch_mount

# Create two test subvolumes, we'll reflink files between them.
$BTRFS_UTIL_PROG subvolume create $SCRATCH_MNT/subv1 | _filter_scratch
$BTRFS_UTIL_PROG subvolume create $SCRATCH_MNT/subv2 | _filter_scratch

echo
echo "Testing with same subvolume and without transaction commit"
echo
run_test "$SCRATCH_MNT/subv1/f1" "$SCRATCH_MNT/subv1/f2" 0

echo
echo "Testing with same subvolume and with transaction commit"
echo
run_test "$SCRATCH_MNT/subv1/f3" "$SCRATCH_MNT/subv1/f4" 1

echo
echo "Testing with different subvolumes and without transaction commit"
echo
run_test "$SCRATCH_MNT/subv1/f5" "$SCRATCH_MNT/subv2/f6" 0

echo
echo "Testing with different subvolumes and with transaction commit"
echo
run_test "$SCRATCH_MNT/subv1/f7" "$SCRATCH_MNT/subv2/f8" 1

# success, all done
status=0
exit