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
 90typedef struct {
 91	__u32 v32;
 92} __attribute__((packed)) jint32_t;
 93
 94typedef struct {
 95	__u32 m;
 96} __attribute__((packed)) jmode_t;
 97
 98typedef struct {
 99	__u16 v16;
100} __attribute__((packed)) jint16_t;
101
102struct 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
111struct 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[];
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*/
135struct 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[];
159};
160
161struct 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[];
174} __attribute__((packed));
175
176struct 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
188struct 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[]; 	/* inode summary info */
200};
201
202union 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. */
213union jffs2_device_node {
214	jint16_t old_id;
215	jint32_t new_id;
216};
217
218#endif /* __LINUX_JFFS2_H__ */