blob: 419fc953ac16ee0d52e67ebaa258efd578bfb7b9 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
4 * Copyright (C) 2001-2003 Red Hat, Inc.
5 *
6 * Created by David Woodhouse <dwmw2@infradead.org>
7 *
8 * For licensing information, see the file 'LICENCE' in the
9 * jffs2 directory.
10 *
11 * $Id: jffs2.h,v 1.34 2004/11/16 20:36:14 dwmw2 Exp $
12 *
13 */
14
15#ifndef __LINUX_JFFS2_H__
16#define __LINUX_JFFS2_H__
17
18/* You must include something which defines the C99 uintXX_t types.
19 We don't do it from here because this file is used in too many
20 different environments. */
21
22#define JFFS2_SUPER_MAGIC 0x72b6
23
24/* Values we may expect to find in the 'magic' field */
25#define JFFS2_OLD_MAGIC_BITMASK 0x1984
26#define JFFS2_MAGIC_BITMASK 0x1985
27#define KSAMTIB_CIGAM_2SFFJ 0x8519 /* For detecting wrong-endian fs */
28#define JFFS2_EMPTY_BITMASK 0xffff
29#define JFFS2_DIRTY_BITMASK 0x0000
30
31/* We only allow a single char for length, and 0xFF is empty flash so
32 we don't want it confused with a real length. Hence max 254.
33*/
34#define JFFS2_MAX_NAME_LEN 254
35
36/* How small can we sensibly write nodes? */
37#define JFFS2_MIN_DATA_LEN 128
38
39#define JFFS2_COMPR_NONE 0x00
40#define JFFS2_COMPR_ZERO 0x01
41#define JFFS2_COMPR_RTIME 0x02
42#define JFFS2_COMPR_RUBINMIPS 0x03
43#define JFFS2_COMPR_COPY 0x04
44#define JFFS2_COMPR_DYNRUBIN 0x05
45#define JFFS2_COMPR_ZLIB 0x06
46#define JFFS2_COMPR_LZO 0x07
47#define JFFS2_COMPR_LZARI 0x08
48/* Compatibility flags. */
49#define JFFS2_COMPAT_MASK 0xc000 /* What do to if an unknown nodetype is found */
50#define JFFS2_NODE_ACCURATE 0x2000
51/* INCOMPAT: Fail to mount the filesystem */
52#define JFFS2_FEATURE_INCOMPAT 0xc000
53/* ROCOMPAT: Mount read-only */
54#define JFFS2_FEATURE_ROCOMPAT 0x8000
55/* RWCOMPAT_COPY: Mount read/write, and copy the node when it's GC'd */
56#define JFFS2_FEATURE_RWCOMPAT_COPY 0x4000
57/* RWCOMPAT_DELETE: Mount read/write, and delete the node when it's GC'd */
58#define JFFS2_FEATURE_RWCOMPAT_DELETE 0x0000
59
60#define JFFS2_NODETYPE_DIRENT (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 1)
61#define JFFS2_NODETYPE_INODE (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 2)
62#define JFFS2_NODETYPE_CLEANMARKER (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 3)
63#define JFFS2_NODETYPE_PADDING (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 4)
64
65// Maybe later...
66//#define JFFS2_NODETYPE_CHECKPOINT (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 3)
67//#define JFFS2_NODETYPE_OPTIONS (JFFS2_FEATURE_RWCOMPAT_COPY | JFFS2_NODE_ACCURATE | 4)
68
69
70#define JFFS2_INO_FLAG_PREREAD 1 /* Do read_inode() for this one at
71 mount time, don't wait for it to
72 happen later */
73#define JFFS2_INO_FLAG_USERCOMPR 2 /* User has requested a specific
74 compression type */
75
76
77/* These can go once we've made sure we've caught all uses without
78 byteswapping */
79
80typedef struct {
81 uint32_t v32;
82} __attribute__((packed)) jint32_t;
83
84typedef struct {
85 uint32_t m;
86} __attribute__((packed)) jmode_t;
87
88typedef struct {
89 uint16_t v16;
90} __attribute__((packed)) jint16_t;
91
92struct jffs2_unknown_node
93{
94 /* All start like this */
95 jint16_t magic;
96 jint16_t nodetype;
97 jint32_t totlen; /* So we can skip over nodes we don't grok */
98 jint32_t hdr_crc;
99} __attribute__((packed));
100
101struct jffs2_raw_dirent
102{
103 jint16_t magic;
104 jint16_t nodetype; /* == JFFS_NODETYPE_DIRENT */
105 jint32_t totlen;
106 jint32_t hdr_crc;
107 jint32_t pino;
108 jint32_t version;
109 jint32_t ino; /* == zero for unlink */
110 jint32_t mctime;
111 uint8_t nsize;
112 uint8_t type;
113 uint8_t unused[2];
114 jint32_t node_crc;
115 jint32_t name_crc;
116 uint8_t name[0];
117} __attribute__((packed));
118
119/* The JFFS2 raw inode structure: Used for storage on physical media. */
120/* The uid, gid, atime, mtime and ctime members could be longer, but
121 are left like this for space efficiency. If and when people decide
122 they really need them extended, it's simple enough to add support for
123 a new type of raw node.
124*/
125struct jffs2_raw_inode
126{
127 jint16_t magic; /* A constant magic number. */
128 jint16_t nodetype; /* == JFFS_NODETYPE_INODE */
129 jint32_t totlen; /* Total length of this node (inc data, etc.) */
130 jint32_t hdr_crc;
131 jint32_t ino; /* Inode number. */
132 jint32_t version; /* Version number. */
133 jmode_t mode; /* The file's type or mode. */
134 jint16_t uid; /* The file's owner. */
135 jint16_t gid; /* The file's group. */
136 jint32_t isize; /* Total resultant size of this inode (used for truncations) */
137 jint32_t atime; /* Last access time. */
138 jint32_t mtime; /* Last modification time. */
139 jint32_t ctime; /* Change time. */
140 jint32_t offset; /* Where to begin to write. */
141 jint32_t csize; /* (Compressed) data size */
142 jint32_t dsize; /* Size of the node's data. (after decompression) */
143 uint8_t compr; /* Compression algorithm used */
144 uint8_t usercompr; /* Compression algorithm requested by the user */
145 jint16_t flags; /* See JFFS2_INO_FLAG_* */
146 jint32_t data_crc; /* CRC for the (compressed) data. */
147 jint32_t node_crc; /* CRC for the raw inode (excluding data) */
148 uint8_t data[0];
149} __attribute__((packed));
150
151union jffs2_node_union {
152 struct jffs2_raw_inode i;
153 struct jffs2_raw_dirent d;
154 struct jffs2_unknown_node u;
155};
156
157#endif /* __LINUX_JFFS2_H__ */