1 /*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
4 * Copyright © 2001-2007 Red Hat, Inc.
5 * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
6 *
7 * Created by David Woodhouse <dwmw2@infradead.org>
8 *
9 * For licensing information, see the file 'LICENCE' in the
10 * jffs2 directory.
11 */
12
13 #ifndef __LINUX_JFFS2_H__
14 #define __LINUX_JFFS2_H__
15
16 #include <linux/types.h>
17 #include <linux/magic.h>
18
19 /* You must include something which defines the C99 uintXX_t types.
20 We don't do it from here because this file is used in too many
21 different environments. */
22
23 /* Values we may expect to find in the 'magic' field */
24 #define JFFS2_OLD_MAGIC_BITMASK 0x1984
25 #define JFFS2_MAGIC_BITMASK 0x1985
26 #define KSAMTIB_CIGAM_2SFFJ 0x8519 /* For detecting wrong-endian fs */
27 #define JFFS2_EMPTY_BITMASK 0xffff
28 #define JFFS2_DIRTY_BITMASK 0x0000
29
30 /* Summary node MAGIC marker */
31 #define JFFS2_SUM_MAGIC 0x02851885
32
33 /* We only allow a single char for length, and 0xFF is empty flash so
34 we don't want it confused with a real length. Hence max 254.
35 */
36 #define JFFS2_MAX_NAME_LEN 254
37
38 /* How small can we sensibly write nodes? */
39 #define JFFS2_MIN_DATA_LEN 128
40
41 #define JFFS2_COMPR_NONE 0x00
42 #define JFFS2_COMPR_ZERO 0x01
43 #define JFFS2_COMPR_RTIME 0x02
44 #define JFFS2_COMPR_RUBINMIPS 0x03
45 #define JFFS2_COMPR_COPY 0x04
46 #define JFFS2_COMPR_DYNRUBIN 0x05
47 #define JFFS2_COMPR_ZLIB 0x06
48 #define JFFS2_COMPR_LZO 0x07
49 /* Compatibility flags. */
50 #define JFFS2_COMPAT_MASK 0xc000 /* What do to if an unknown nodetype is found */
51 #define JFFS2_NODE_ACCURATE 0x2000
52 /* INCOMPAT: Fail to mount the filesystem */
53 #define JFFS2_FEATURE_INCOMPAT 0xc000
54 /* ROCOMPAT: Mount read-only */
55 #define JFFS2_FEATURE_ROCOMPAT 0x8000
56 /* RWCOMPAT_COPY: Mount read/write, and copy the node when it's GC'd */
57 #define JFFS2_FEATURE_RWCOMPAT_COPY 0x4000
58 /* RWCOMPAT_DELETE: Mount read/write, and delete the node when it's GC'd */
59 #define JFFS2_FEATURE_RWCOMPAT_DELETE 0x0000
60
61 #define JFFS2_NODETYPE_DIRENT (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 1)
62 #define JFFS2_NODETYPE_INODE (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 2)
63 #define JFFS2_NODETYPE_CLEANMARKER (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 3)
64 #define JFFS2_NODETYPE_PADDING (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 4)
65
66 #define JFFS2_NODETYPE_SUMMARY (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 6)
67
68 #define JFFS2_NODETYPE_XATTR (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 8)
69 #define JFFS2_NODETYPE_XREF (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 9)
70
71 /* XATTR Related */
72 #define JFFS2_XPREFIX_USER 1 /* for "user." */
73 #define JFFS2_XPREFIX_SECURITY 2 /* for "security." */
74 #define JFFS2_XPREFIX_ACL_ACCESS 3 /* for "system.posix_acl_access" */
75 #define JFFS2_XPREFIX_ACL_DEFAULT 4 /* for "system.posix_acl_default" */
76 #define JFFS2_XPREFIX_TRUSTED 5 /* for "trusted.*" */
77
78 #define JFFS2_ACL_VERSION 0x0001
79
80 #define JFFS2_INO_FLAG_PREREAD 1 /* Do read_inode() for this one at
81 mount time, don't wait for it to
82 happen later */
83 #define JFFS2_INO_FLAG_USERCOMPR 2 /* User has requested a specific
84 compression type */
85
86
87 /* These can go once we've made sure we've caught all uses without
88 byteswapping */
89
90 typedef struct {
91 __u32 v32;
92 } __attribute__((packed)) jint32_t;
93
94 typedef struct {
95 __u32 m;
96 } __attribute__((packed)) jmode_t;
97
98 typedef struct {
99 __u16 v16;
100 } __attribute__((packed)) jint16_t;
101
102 struct jffs2_unknown_node
103 {
104 /* All start like this */
105 jint16_t magic;
106 jint16_t nodetype;
107 jint32_t totlen; /* So we can skip over nodes we don't grok */
108 jint32_t hdr_crc;
109 };
110
111 struct jffs2_raw_dirent
112 {
113 jint16_t magic;
114 jint16_t nodetype; /* == JFFS2_NODETYPE_DIRENT */
115 jint32_t totlen;
116 jint32_t hdr_crc;
117 jint32_t pino;
118 jint32_t version;
119 jint32_t ino; /* == zero for unlink */
120 jint32_t mctime;
121 __u8 nsize;
122 __u8 type;
123 __u8 unused[2];
124 jint32_t node_crc;
125 jint32_t name_crc;
126 __u8 name[0];
127 };
128
129 /* The JFFS2 raw inode structure: Used for storage on physical media. */
130 /* The uid, gid, atime, mtime and ctime members could be longer, but
131 are left like this for space efficiency. If and when people decide
132 they really need them extended, it's simple enough to add support for
133 a new type of raw node.
134 */
135 struct jffs2_raw_inode
136 {
137 jint16_t magic; /* A constant magic number. */
138 jint16_t nodetype; /* == JFFS2_NODETYPE_INODE */
139 jint32_t totlen; /* Total length of this node (inc data, etc.) */
140 jint32_t hdr_crc;
141 jint32_t ino; /* Inode number. */
142 jint32_t version; /* Version number. */
143 jmode_t mode; /* The file's type or mode. */
144 jint16_t uid; /* The file's owner. */
145 jint16_t gid; /* The file's group. */
146 jint32_t isize; /* Total resultant size of this inode (used for truncations) */
147 jint32_t atime; /* Last access time. */
148 jint32_t mtime; /* Last modification time. */
149 jint32_t ctime; /* Change time. */
150 jint32_t offset; /* Where to begin to write. */
151 jint32_t csize; /* (Compressed) data size */
152 jint32_t dsize; /* Size of the node's data. (after decompression) */
153 __u8 compr; /* Compression algorithm used */
154 __u8 usercompr; /* Compression algorithm requested by the user */
155 jint16_t flags; /* See JFFS2_INO_FLAG_* */
156 jint32_t data_crc; /* CRC for the (compressed) data. */
157 jint32_t node_crc; /* CRC for the raw inode (excluding data) */
158 __u8 data[0];
159 };
160
161 struct jffs2_raw_xattr {
162 jint16_t magic;
163 jint16_t nodetype; /* = JFFS2_NODETYPE_XATTR */
164 jint32_t totlen;
165 jint32_t hdr_crc;
166 jint32_t xid; /* XATTR identifier number */
167 jint32_t version;
168 __u8 xprefix;
169 __u8 name_len;
170 jint16_t value_len;
171 jint32_t data_crc;
172 jint32_t node_crc;
173 __u8 data[0];
174 } __attribute__((packed));
175
176 struct jffs2_raw_xref
177 {
178 jint16_t magic;
179 jint16_t nodetype; /* = JFFS2_NODETYPE_XREF */
180 jint32_t totlen;
181 jint32_t hdr_crc;
182 jint32_t ino; /* inode number */
183 jint32_t xid; /* XATTR identifier number */
184 jint32_t xseqno; /* xref sequential number */
185 jint32_t node_crc;
186 } __attribute__((packed));
187
188 struct jffs2_raw_summary
189 {
190 jint16_t magic;
191 jint16_t nodetype; /* = JFFS2_NODETYPE_SUMMARY */
192 jint32_t totlen;
193 jint32_t hdr_crc;
194 jint32_t sum_num; /* number of sum entries*/
195 jint32_t cln_mkr; /* clean marker size, 0 = no cleanmarker */
196 jint32_t padded; /* sum of the size of padding nodes */
197 jint32_t sum_crc; /* summary information crc */
198 jint32_t node_crc; /* node crc */
199 jint32_t sum[0]; /* inode summary info */
200 };
201
202 union jffs2_node_union
203 {
204 struct jffs2_raw_inode i;
205 struct jffs2_raw_dirent d;
206 struct jffs2_raw_xattr x;
207 struct jffs2_raw_xref r;
208 struct jffs2_raw_summary s;
209 struct jffs2_unknown_node u;
210 };
211
212 /* Data payload for device nodes. */
213 union jffs2_device_node {
214 jint16_t old_id;
215 jint32_t new_id;
216 };
217
218 #endif /* __LINUX_JFFS2_H__ */