#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (c) 2021 Anand Jain. All Rights Reserved.
# Copyright (c) 2021 Oracle. All Rights Reserved.
#
# FS QA Test No. 254
#
# Test if the kernel can free the stale device entries.
#
. ./common/preamble
_begin_fstest auto quick volume

# Override the default cleanup function.
node=$seq-test
cleanup_dmdev()
{
	_dmsetup_remove $node
}

_cleanup()
{
	cd /
	rm -f $tmp.*
	rm -rf $seq_mnt > /dev/null 2>&1
	cleanup_dmdev
}

# Import common functions.
. ./common/filter
. ./common/filter.btrfs

# real QA test starts here
_supported_fs btrfs
_require_scratch_dev_pool 3
_require_block_device $SCRATCH_DEV
_require_dm_target linear
_require_btrfs_forget_or_module_loadable
_require_scratch_nocheck
_require_command "$WIPEFS_PROG" wipefs
_check_minimal_fs_size $((1024 * 1024 * 1024))

_fixed_by_kernel_commit 770c79fb6550 \
	"btrfs: harden identification of a stale device"

_scratch_dev_pool_get 3

setup_dmdev()
{
	# Some small size.
	size=$((1024 * 1024 * 1024))
	size_in_sector=$((size / 512))

	table="0 $size_in_sector linear $SCRATCH_DEV 0"
	_dmsetup_create $node --table "$table" || \
		_fail "setup dm device failed"
}

# Use a known it is much easier to debug.
lvdev=/dev/mapper/$node

seq_mnt=$TEST_DIR/$seq.mnt
mkdir -p $seq_mnt

test_forget()
{
	setup_dmdev
	dmdev=$(realpath $lvdev)

	_mkfs_dev $dmdev

	# Check if we can un-scan using the mapper device path.
	$BTRFS_UTIL_PROG device scan --forget $lvdev

	# Cleanup
	$WIPEFS_PROG -a $lvdev > /dev/null 2>&1
	$BTRFS_UTIL_PROG device scan --forget

	cleanup_dmdev
}

test_add_device()
{
	setup_dmdev
	dmdev=$(realpath $lvdev)
	scratch_dev2=$(echo $SCRATCH_DEV_POOL | $AWK_PROG '{print $2}')
	scratch_dev3=$(echo $SCRATCH_DEV_POOL | $AWK_PROG '{print $3}')

	_mkfs_dev $scratch_dev3
	_mount $scratch_dev3 $seq_mnt

	_mkfs_dev -draid1 -mraid1 $lvdev $scratch_dev2

	# Added device should free the stale device in the kernel.
	$BTRFS_UTIL_PROG device add -f $dmdev $seq_mnt > /dev/null 2>&1

	_mount -o degraded $scratch_dev2 $SCRATCH_MNT

	# Check if the missing device is shown.
	$BTRFS_UTIL_PROG filesystem show -m $SCRATCH_MNT | \
					_filter_btrfs_filesystem_show

	$UMOUNT_PROG $seq_mnt
	_scratch_unmount
	cleanup_dmdev
}

test_forget
test_add_device

_scratch_dev_pool_put

status=0
exit