ext4_sb.c

/*
 * Copyright (C) 2014 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <errno.h>

#include "ext4_sb.h"

int ext4_parse_sb(struct ext4_super_block *sb, struct fs_info *info)
{
	uint64_t len_blocks;

        if (sb->s_magic != EXT4_SUPER_MAGIC)
                return -EINVAL;

        if ((sb->s_state & EXT4_VALID_FS) != EXT4_VALID_FS)
                return -EINVAL;

	info->block_size = 1024 << sb->s_log_block_size;
	info->blocks_per_group = sb->s_blocks_per_group;
	info->inodes_per_group = sb->s_inodes_per_group;
	info->inode_size = sb->s_inode_size;
	info->inodes = sb->s_inodes_count;
	info->feat_ro_compat = sb->s_feature_ro_compat;
	info->feat_compat = sb->s_feature_compat;
	info->feat_incompat = sb->s_feature_incompat;
	info->bg_desc_reserve_blocks = sb->s_reserved_gdt_blocks;
	info->label = sb->s_volume_name;

	len_blocks = ((uint64_t)sb->s_blocks_count_hi << 32) +
                sb->s_blocks_count_lo;
	info->len = (uint64_t)info->block_size * len_blocks;

	return 0;
}