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      1 /*
      2  * JFFS2 -- Journalling Flash File System, Version 2.
      3  *
      4  * Copyright (C) 2001-2003 Red Hat, Inc.
      5  *
      6  * Created by David Woodhouse <dwmw2 (at) infradead.org>
      7  *
      8  * For licensing information, see the file 'LICENCE' in the
      9  * jffs2 directory.
     10  *
     11  * $Id: jffs2.h,v 1.38 2005/09/26 11:37:23 havasi Exp $
     12  *
     13  */
     14 
     15 #ifndef __LINUX_JFFS2_H__
     16 #define __LINUX_JFFS2_H__
     17 
     18 #include <linux/magic.h>
     19 
     20 /* You must include something which defines the C99 uintXX_t types.
     21    We don't do it from here because this file is used in too many
     22    different environments. */
     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 /* Summary node MAGIC marker */
     32 #define JFFS2_SUM_MAGIC	0x02851885
     33 
     34 /* We only allow a single char for length, and 0xFF is empty flash so
     35    we don't want it confused with a real length. Hence max 254.
     36 */
     37 #define JFFS2_MAX_NAME_LEN 254
     38 
     39 /* How small can we sensibly write nodes? */
     40 #define JFFS2_MIN_DATA_LEN 128
     41 
     42 #define JFFS2_COMPR_NONE	0x00
     43 #define JFFS2_COMPR_ZERO	0x01
     44 #define JFFS2_COMPR_RTIME	0x02
     45 #define JFFS2_COMPR_RUBINMIPS	0x03
     46 #define JFFS2_COMPR_COPY	0x04
     47 #define JFFS2_COMPR_DYNRUBIN	0x05
     48 #define JFFS2_COMPR_ZLIB	0x06
     49 #define JFFS2_COMPR_LZO		0x07
     50 /* Compatibility flags. */
     51 #define JFFS2_COMPAT_MASK 0xc000      /* What do to if an unknown nodetype is found */
     52 #define JFFS2_NODE_ACCURATE 0x2000
     53 /* INCOMPAT: Fail to mount the filesystem */
     54 #define JFFS2_FEATURE_INCOMPAT 0xc000
     55 /* ROCOMPAT: Mount read-only */
     56 #define JFFS2_FEATURE_ROCOMPAT 0x8000
     57 /* RWCOMPAT_COPY: Mount read/write, and copy the node when it's GC'd */
     58 #define JFFS2_FEATURE_RWCOMPAT_COPY 0x4000
     59 /* RWCOMPAT_DELETE: Mount read/write, and delete the node when it's GC'd */
     60 #define JFFS2_FEATURE_RWCOMPAT_DELETE 0x0000
     61 
     62 #define JFFS2_NODETYPE_DIRENT (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 1)
     63 #define JFFS2_NODETYPE_INODE (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 2)
     64 #define JFFS2_NODETYPE_CLEANMARKER (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 3)
     65 #define JFFS2_NODETYPE_PADDING (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 4)
     66 
     67 #define JFFS2_NODETYPE_SUMMARY (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 6)
     68 
     69 #define JFFS2_NODETYPE_XATTR (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 8)
     70 #define JFFS2_NODETYPE_XREF (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 9)
     71 
     72 /* XATTR Related */
     73 #define JFFS2_XPREFIX_USER		1	/* for "user." */
     74 #define JFFS2_XPREFIX_SECURITY		2	/* for "security." */
     75 #define JFFS2_XPREFIX_ACL_ACCESS	3	/* for "system.posix_acl_access" */
     76 #define JFFS2_XPREFIX_ACL_DEFAULT	4	/* for "system.posix_acl_default" */
     77 #define JFFS2_XPREFIX_TRUSTED		5	/* for "trusted.*" */
     78 
     79 #define JFFS2_ACL_VERSION		0x0001
     80 
     81 // Maybe later...
     82 //#define JFFS2_NODETYPE_CHECKPOINT (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 3)
     83 //#define JFFS2_NODETYPE_OPTIONS (JFFS2_FEATURE_RWCOMPAT_COPY | JFFS2_NODE_ACCURATE | 4)
     84 
     85 
     86 #define JFFS2_INO_FLAG_PREREAD	  1	/* Do read_inode() for this one at
     87 					   mount time, don't wait for it to
     88 					   happen later */
     89 #define JFFS2_INO_FLAG_USERCOMPR  2	/* User has requested a specific
     90 					   compression type */
     91 
     92 
     93 /* These can go once we've made sure we've caught all uses without
     94    byteswapping */
     95 
     96 typedef struct {
     97 	uint32_t v32;
     98 } __attribute__((packed)) jint32_t;
     99 
    100 typedef struct {
    101 	uint32_t m;
    102 } __attribute__((packed)) jmode_t;
    103 
    104 typedef struct {
    105 	uint16_t v16;
    106 } __attribute__((packed)) jint16_t;
    107 
    108 struct jffs2_unknown_node
    109 {
    110 	/* All start like this */
    111 	jint16_t magic;
    112 	jint16_t nodetype;
    113 	jint32_t totlen; /* So we can skip over nodes we don't grok */
    114 	jint32_t hdr_crc;
    115 };
    116 
    117 struct jffs2_raw_dirent
    118 {
    119 	jint16_t magic;
    120 	jint16_t nodetype;	/* == JFFS2_NODETYPE_DIRENT */
    121 	jint32_t totlen;
    122 	jint32_t hdr_crc;
    123 	jint32_t pino;
    124 	jint32_t version;
    125 	jint32_t ino; /* == zero for unlink */
    126 	jint32_t mctime;
    127 	uint8_t nsize;
    128 	uint8_t type;
    129 	uint8_t unused[2];
    130 	jint32_t node_crc;
    131 	jint32_t name_crc;
    132 	uint8_t name[0];
    133 };
    134 
    135 /* The JFFS2 raw inode structure: Used for storage on physical media.  */
    136 /* The uid, gid, atime, mtime and ctime members could be longer, but
    137    are left like this for space efficiency. If and when people decide
    138    they really need them extended, it's simple enough to add support for
    139    a new type of raw node.
    140 */
    141 struct jffs2_raw_inode
    142 {
    143 	jint16_t magic;      /* A constant magic number.  */
    144 	jint16_t nodetype;   /* == JFFS2_NODETYPE_INODE */
    145 	jint32_t totlen;     /* Total length of this node (inc data, etc.) */
    146 	jint32_t hdr_crc;
    147 	jint32_t ino;        /* Inode number.  */
    148 	jint32_t version;    /* Version number.  */
    149 	jmode_t mode;       /* The file's type or mode.  */
    150 	jint16_t uid;        /* The file's owner.  */
    151 	jint16_t gid;        /* The file's group.  */
    152 	jint32_t isize;      /* Total resultant size of this inode (used for truncations)  */
    153 	jint32_t atime;      /* Last access time.  */
    154 	jint32_t mtime;      /* Last modification time.  */
    155 	jint32_t ctime;      /* Change time.  */
    156 	jint32_t offset;     /* Where to begin to write.  */
    157 	jint32_t csize;      /* (Compressed) data size */
    158 	jint32_t dsize;	     /* Size of the node's data. (after decompression) */
    159 	uint8_t compr;       /* Compression algorithm used */
    160 	uint8_t usercompr;   /* Compression algorithm requested by the user */
    161 	jint16_t flags;	     /* See JFFS2_INO_FLAG_* */
    162 	jint32_t data_crc;   /* CRC for the (compressed) data.  */
    163 	jint32_t node_crc;   /* CRC for the raw inode (excluding data)  */
    164 	uint8_t data[0];
    165 };
    166 
    167 struct jffs2_raw_xattr {
    168 	jint16_t magic;
    169 	jint16_t nodetype;	/* = JFFS2_NODETYPE_XATTR */
    170 	jint32_t totlen;
    171 	jint32_t hdr_crc;
    172 	jint32_t xid;		/* XATTR identifier number */
    173 	jint32_t version;
    174 	uint8_t xprefix;
    175 	uint8_t name_len;
    176 	jint16_t value_len;
    177 	jint32_t data_crc;
    178 	jint32_t node_crc;
    179 	uint8_t data[0];
    180 } __attribute__((packed));
    181 
    182 struct jffs2_raw_xref
    183 {
    184 	jint16_t magic;
    185 	jint16_t nodetype;	/* = JFFS2_NODETYPE_XREF */
    186 	jint32_t totlen;
    187 	jint32_t hdr_crc;
    188 	jint32_t ino;		/* inode number */
    189 	jint32_t xid;		/* XATTR identifier number */
    190 	jint32_t xseqno;	/* xref sequencial number */
    191 	jint32_t node_crc;
    192 } __attribute__((packed));
    193 
    194 struct jffs2_raw_summary
    195 {
    196 	jint16_t magic;
    197 	jint16_t nodetype; 	/* = JFFS2_NODETYPE_SUMMARY */
    198 	jint32_t totlen;
    199 	jint32_t hdr_crc;
    200 	jint32_t sum_num;	/* number of sum entries*/
    201 	jint32_t cln_mkr;	/* clean marker size, 0 = no cleanmarker */
    202 	jint32_t padded;	/* sum of the size of padding nodes */
    203 	jint32_t sum_crc;	/* summary information crc */
    204 	jint32_t node_crc; 	/* node crc */
    205 	jint32_t sum[0]; 	/* inode summary info */
    206 };
    207 
    208 union jffs2_node_union
    209 {
    210 	struct jffs2_raw_inode i;
    211 	struct jffs2_raw_dirent d;
    212 	struct jffs2_raw_xattr x;
    213 	struct jffs2_raw_xref r;
    214 	struct jffs2_raw_summary s;
    215 	struct jffs2_unknown_node u;
    216 };
    217 
    218 /* Data payload for device nodes. */
    219 union jffs2_device_node {
    220 	jint16_t old;
    221 	jint32_t new;
    222 };
    223 
    224 #endif /* __LINUX_JFFS2_H__ */
    225