busybox/util-linux/volume_id/ubifs.c

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/*
* volume_id - reads filesystem label and uuid
*
* Copyright (C) 2012 S-G Bergh <sgb@systemasis.org>
*
* Licensed under GPLv2, see file LICENSE in this source tree.
*/
//kbuild:lib-$(CONFIG_FEATURE_VOLUMEID_UBIFS) += ubifs.o
//config:config FEATURE_VOLUMEID_UBIFS
//config: bool "UBIFS filesystem"
//config: default y
//config: depends on VOLUMEID
//config: help
//config: UBIFS (Unsorted Block Image File System) is a file
//config: system for use with raw flash memory media.
#include "volume_id_internal.h"
#define UBIFS_NODE_MAGIC 0x06101831
/*
* struct ubifs_ch - common header node.
* @magic: UBIFS node magic number (%UBIFS_NODE_MAGIC)
* @crc: CRC-32 checksum of the node header
* @sqnum: sequence number
* @len: full node length
* @node_type: node type
* @group_type: node group type
* @padding: reserved for future, zeroes
*
* Every UBIFS node starts with this common part. If the node has a key, the
* key always goes next.
*/
struct ubifs_ch {
uint32_t magic;
uint32_t crc;
uint64_t sqnum;
uint32_t len;
uint8_t node_type;
uint8_t group_type;
uint8_t padding[2];
} PACKED;
/*
* struct ubifs_sb_node - superblock node.
* @ch: common header
* @padding: reserved for future, zeroes
* @key_hash: type of hash function used in keys
* @key_fmt: format of the key
* @flags: file-system flags (%UBIFS_FLG_BIGLPT, etc)
* @min_io_size: minimal input/output unit size
* @leb_size: logical eraseblock size in bytes
* @leb_cnt: count of LEBs used by file-system
* @max_leb_cnt: maximum count of LEBs used by file-system
* @max_bud_bytes: maximum amount of data stored in buds
* @log_lebs: log size in logical eraseblocks
* @lpt_lebs: number of LEBs used for lprops table
* @orph_lebs: number of LEBs used for recording orphans
* @jhead_cnt: count of journal heads
* @fanout: tree fanout (max. number of links per indexing node)
* @lsave_cnt: number of LEB numbers in LPT's save table
* @fmt_version: UBIFS on-flash format version
* @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc)
* @padding1: reserved for future, zeroes
* @rp_uid: reserve pool UID
* @rp_gid: reserve pool GID
* @rp_size: size of the reserved pool in bytes
* @padding2: reserved for future, zeroes
* @time_gran: time granularity in nanoseconds
* @uuid: UUID generated when the file system image was created
* @ro_compat_version: UBIFS R/O compatibility version
*/
struct ubifs_sb_node {
struct ubifs_ch ch;
uint8_t padding[2];
uint8_t key_hash;
uint8_t key_fmt;
uint32_t flags;
uint32_t min_io_size;
uint32_t leb_size;
uint32_t leb_cnt;
uint32_t max_leb_cnt;
uint64_t max_bud_bytes;
uint32_t log_lebs;
uint32_t lpt_lebs;
uint32_t orph_lebs;
uint32_t jhead_cnt;
uint32_t fanout;
uint32_t lsave_cnt;
uint32_t fmt_version;
uint16_t default_compr;
uint8_t padding1[2];
uint32_t rp_uid;
uint32_t rp_gid;
uint64_t rp_size;
uint32_t time_gran;
uint8_t uuid[16];
uint32_t ro_compat_version;
/*
uint8_t padding2[3968];
*/
} PACKED;
int FAST_FUNC volume_id_probe_ubifs(struct volume_id *id /*,uint64_t off*/)
{
#define off ((uint64_t)0)
struct ubifs_sb_node *sb;
dbg("UBIFS: probing at offset 0x%llx", (unsigned long long) off);
sb = volume_id_get_buffer(id, off, sizeof(struct ubifs_sb_node));
if (!sb)
return -1;
if (le32_to_cpu(sb->ch.magic) != UBIFS_NODE_MAGIC)
return -1;
IF_FEATURE_BLKID_TYPE(id->type = "ubifs";)
volume_id_set_uuid(id, sb->uuid, UUID_DCE);
return 0;
}