#! /bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (c) 2025 SUSE S.A.  All Rights Reserved.
#
# FS QA Test No. 342
#
# Test free space tree mount options, for newer kernels with only 2 options involed:
# - No space cache
# - New (default) v2 space cache
#
. ./common/preamble
_begin_fstest auto quick

_require_scratch
_require_btrfs_command inspect-internal dump-super
_require_btrfs_fs_feature free_space_tree

# The block-group-tree feature relies on v2 cache, thus it doesn't support
# "nospace_cache" mount option.
_require_btrfs_no_block_group_tree

mkfs_nocache()
{
	_scratch_mkfs >/dev/null 2>&1
	_scratch_mount -o clear_cache,nospace_cache
	_scratch_unmount
}

mkfs_v2()
{
	_scratch_mkfs >/dev/null 2>&1
	_scratch_mount -o space_cache=v2
	_scratch_unmount
}

check_fst_compat()
{
	compat_ro="$($BTRFS_UTIL_PROG inspect-internal dump-super "$SCRATCH_DEV" | \
		     sed -rn 's/^compat_ro_flags\s+(.*)$/\1/p')"
	if ((compat_ro & 0x1)); then
		echo "free space tree is enabled"
	else
		echo "free space tree is disabled"
	fi
}

# Mount options might interfere.
export MOUNT_OPTIONS=""

# When the free space tree is not enabled:
# -o space_cache=v2: enable the free space tree
# -o clear_cache,space_cache=v2: clear the old space cache and enable the free space tree
# We don't check the no options case or plain space_cache as that will change
# in the future to turn on space_cache=v2.

mkfs_nocache
echo "Using no space cache"
_scratch_mount -o nospace_cache
check_fst_compat
_scratch_unmount

mkfs_nocache
echo "Enabling free space tree"
_scratch_mount -o space_cache=v2
check_fst_compat
_scratch_unmount

# When the free space tree is enabled:
# -o nospace_cache: error
# no options, -o space_cache=v2: keep using the free space tree
# -o clear_cache, -o clear_cache,space_cache=v2: clear and recreate the free space tree
# -o clear_cache,nospace_cache: clear the free space tree

mkfs_v2
echo "Trying to mount without free space tree"
_try_scratch_mount -o nospace_cache >/dev/null 2>&1 || echo "mount failed"

mkfs_v2
echo "Mounting existing free space tree"
_scratch_mount
check_fst_compat
_scratch_unmount
_scratch_mount -o space_cache=v2
check_fst_compat
_scratch_unmount

mkfs_v2
echo "Recreating free space tree"
_scratch_mount -o clear_cache,space_cache=v2
check_fst_compat
_scratch_unmount
mkfs_v2
_scratch_mount -o clear_cache
check_fst_compat
_scratch_unmount

mkfs_v2
echo "Disabling free space tree"
_scratch_mount -o clear_cache,nospace_cache
check_fst_compat
_scratch_unmount

_exit 0
