path: root/util-linux/volume_id/ubifs.c (plain)
blob: 13604ec35c8921a603d7da83b7f09e78396488d9

1	/*
2	* volume_id - reads filesystem label and uuid
3	*
4	* Copyright (C) 2012 S-G Bergh <sgb@systemasis.org>
5	*
6	* Licensed under GPLv2, see file LICENSE in this source tree.
7	*/
8
9	//kbuild:lib-$(CONFIG_FEATURE_VOLUMEID_UBIFS) += ubifs.o
10
11	//config:
12	//config:config FEATURE_VOLUMEID_UBIFS
13	//config: bool "UBIFS filesystem"
14	//config: default y
15	//config: depends on VOLUMEID
16	//config: help
17	//config: UBIFS (Unsorted Block Image File System) is a file
18	//config: system for use with raw flash memory media.
19	//config:
20
21	#include "volume_id_internal.h"
22
23	#define UBIFS_NODE_MAGIC 0x06101831
24
25	/*
26	* struct ubifs_ch - common header node.
27	* @magic: UBIFS node magic number (%UBIFS_NODE_MAGIC)
28	* @crc: CRC-32 checksum of the node header
29	* @sqnum: sequence number
30	* @len: full node length
31	* @node_type: node type
32	* @group_type: node group type
33	* @padding: reserved for future, zeroes
34	*
35	* Every UBIFS node starts with this common part. If the node has a key, the
36	* key always goes next.
37	*/
38	struct ubifs_ch {
39	uint32_t magic;
40	uint32_t crc;
41	uint64_t sqnum;
42	uint32_t len;
43	uint8_t node_type;
44	uint8_t group_type;
45	uint8_t padding[2];
46	} PACKED;
47
48	/*
49	* struct ubifs_sb_node - superblock node.
50	* @ch: common header
51	* @padding: reserved for future, zeroes
52	* @key_hash: type of hash function used in keys
53	* @key_fmt: format of the key
54	* @flags: file-system flags (%UBIFS_FLG_BIGLPT, etc)
55	* @min_io_size: minimal input/output unit size
56	* @leb_size: logical eraseblock size in bytes
57	* @leb_cnt: count of LEBs used by file-system
58	* @max_leb_cnt: maximum count of LEBs used by file-system
59	* @max_bud_bytes: maximum amount of data stored in buds
60	* @log_lebs: log size in logical eraseblocks
61	* @lpt_lebs: number of LEBs used for lprops table
62	* @orph_lebs: number of LEBs used for recording orphans
63	* @jhead_cnt: count of journal heads
64	* @fanout: tree fanout (max. number of links per indexing node)
65	* @lsave_cnt: number of LEB numbers in LPT's save table
66	* @fmt_version: UBIFS on-flash format version
67	* @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc)
68	* @padding1: reserved for future, zeroes
69	* @rp_uid: reserve pool UID
70	* @rp_gid: reserve pool GID
71	* @rp_size: size of the reserved pool in bytes
72	* @padding2: reserved for future, zeroes
73	* @time_gran: time granularity in nanoseconds
74	* @uuid: UUID generated when the file system image was created
75	* @ro_compat_version: UBIFS R/O compatibility version
76	*/
77	struct ubifs_sb_node {
78	struct ubifs_ch ch;
79	uint8_t padding[2];
80	uint8_t key_hash;
81	uint8_t key_fmt;
82	uint32_t flags;
83	uint32_t min_io_size;
84	uint32_t leb_size;
85	uint32_t leb_cnt;
86	uint32_t max_leb_cnt;
87	uint64_t max_bud_bytes;
88	uint32_t log_lebs;
89	uint32_t lpt_lebs;
90	uint32_t orph_lebs;
91	uint32_t jhead_cnt;
92	uint32_t fanout;
93	uint32_t lsave_cnt;
94	uint32_t fmt_version;
95	uint16_t default_compr;
96	uint8_t padding1[2];
97	uint32_t rp_uid;
98	uint32_t rp_gid;
99	uint64_t rp_size;
100	uint32_t time_gran;
101	uint8_t uuid[16];
102	uint32_t ro_compat_version;
103	/*
104	uint8_t padding2[3968];
105	*/
106	} PACKED;
107
108	int FAST_FUNC volume_id_probe_ubifs(struct volume_id *id /*,uint64_t off*/)
109	{
110	#define off ((uint64_t)0)
111	struct ubifs_sb_node *sb;
112
113	dbg("UBIFS: probing at offset 0x%llx", (unsigned long long) off);
114	sb = volume_id_get_buffer(id, off, sizeof(struct ubifs_sb_node));
115	if (!sb)
116	return -1;
117
118	if (le32_to_cpu(sb->ch.magic) != UBIFS_NODE_MAGIC)
119	return -1;
120
121	IF_FEATURE_BLKID_TYPE(id->type = "ubifs";)
122	volume_id_set_uuid(id, sb->uuid, UUID_DCE);
123
124	return 0;
125	}
126