package/mtd/src/jffs2.h

   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@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 #define JFFS2_SUPER_MAGIC   0x72b6
  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 /* 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 // Maybe later...
  81 //#define JFFS2_NODETYPE_CHECKPOINT (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 3)
  82 //#define JFFS2_NODETYPE_OPTIONS (JFFS2_FEATURE_RWCOMPAT_COPY | JFFS2_NODE_ACCURATE | 4)
  83
  84
  85 #define JFFS2_INO_FLAG_PREREAD    1     /* Do read_inode() for this one at
  86                                            mount time, don't wait for it to
  87                                            happen later */
  88 #define JFFS2_INO_FLAG_USERCOMPR  2     /* User has requested a specific
  89                                            compression type */
  90
  91
  92 /* These can go once we've made sure we've caught all uses without
  93    byteswapping */
  94
  95 typedef uint32_t jint32_t;
  96
  97 typedef uint32_t jmode_t;
  98
  99 typedef uint16_t jint16_t;
 100
 101 struct jffs2_unknown_node
 102 {
 103         /* All start like this */
 104         jint16_t magic;
 105         jint16_t nodetype;
 106         jint32_t totlen; /* So we can skip over nodes we don't grok */
 107         jint32_t hdr_crc;
 108 };
 109
 110 struct jffs2_raw_dirent
 111 {
 112         jint16_t magic;
 113         jint16_t nodetype;      /* == JFFS2_NODETYPE_DIRENT */
 114         jint32_t totlen;
 115         jint32_t hdr_crc;
 116         jint32_t pino;
 117         jint32_t version;
 118         jint32_t ino; /* == zero for unlink */
 119         jint32_t mctime;
 120         uint8_t nsize;
 121         uint8_t type;
 122         uint8_t unused[2];
 123         jint32_t node_crc;
 124         jint32_t name_crc;
 125         uint8_t name[0];
 126 };
 127
 128 /* The JFFS2 raw inode structure: Used for storage on physical media.  */
 129 /* The uid, gid, atime, mtime and ctime members could be longer, but
 130    are left like this for space efficiency. If and when people decide
 131    they really need them extended, it's simple enough to add support for
 132    a new type of raw node.
 133 */
 134 struct jffs2_raw_inode
 135 {
 136         jint16_t magic;      /* A constant magic number.  */
 137         jint16_t nodetype;   /* == JFFS2_NODETYPE_INODE */
 138         jint32_t totlen;     /* Total length of this node (inc data, etc.) */
 139         jint32_t hdr_crc;
 140         jint32_t ino;        /* Inode number.  */
 141         jint32_t version;    /* Version number.  */
 142         jmode_t mode;       /* The file's type or mode.  */
 143         jint16_t uid;        /* The file's owner.  */
 144         jint16_t gid;        /* The file's group.  */
 145         jint32_t isize;      /* Total resultant size of this inode (used for truncations)  */
 146         jint32_t atime;      /* Last access time.  */
 147         jint32_t mtime;      /* Last modification time.  */
 148         jint32_t ctime;      /* Change time.  */
 149         jint32_t offset;     /* Where to begin to write.  */
 150         jint32_t csize;      /* (Compressed) data size */
 151         jint32_t dsize;      /* Size of the node's data. (after decompression) */
 152         uint8_t compr;       /* Compression algorithm used */
 153         uint8_t usercompr;   /* Compression algorithm requested by the user */
 154         jint16_t flags;      /* See JFFS2_INO_FLAG_* */
 155         jint32_t data_crc;   /* CRC for the (compressed) data.  */
 156         jint32_t node_crc;   /* CRC for the raw inode (excluding data)  */
 157         uint8_t data[0];
 158 };
 159
 160 struct jffs2_raw_xattr {
 161         jint16_t magic;
 162         jint16_t nodetype;      /* = JFFS2_NODETYPE_XATTR */
 163         jint32_t totlen;
 164         jint32_t hdr_crc;
 165         jint32_t xid;           /* XATTR identifier number */
 166         jint32_t version;
 167         uint8_t xprefix;
 168         uint8_t name_len;
 169         jint16_t value_len;
 170         jint32_t data_crc;
 171         jint32_t node_crc;
 172         uint8_t data[0];
 173 } __attribute__((packed));
 174
 175 struct jffs2_raw_xref
 176 {
 177         jint16_t magic;
 178         jint16_t nodetype;      /* = JFFS2_NODETYPE_XREF */
 179         jint32_t totlen;
 180         jint32_t hdr_crc;
 181         jint32_t ino;           /* inode number */
 182         jint32_t xid;           /* XATTR identifier number */
 183         jint32_t xseqno;        /* xref sequencial number */
 184         jint32_t node_crc;
 185 } __attribute__((packed));
 186
 187 struct jffs2_raw_summary
 188 {
 189         jint16_t magic;
 190         jint16_t nodetype;      /* = JFFS2_NODETYPE_SUMMARY */
 191         jint32_t totlen;
 192         jint32_t hdr_crc;
 193         jint32_t sum_num;       /* number of sum entries*/
 194         jint32_t cln_mkr;       /* clean marker size, 0 = no cleanmarker */
 195         jint32_t padded;        /* sum of the size of padding nodes */
 196         jint32_t sum_crc;       /* summary information crc */
 197         jint32_t node_crc;      /* node crc */
 198         jint32_t sum[0];        /* inode summary info */
 199 };
 200
 201 union jffs2_node_union
 202 {
 203         struct jffs2_raw_inode i;
 204         struct jffs2_raw_dirent d;
 205         struct jffs2_raw_xattr x;
 206         struct jffs2_raw_xref r;
 207         struct jffs2_raw_summary s;
 208         struct jffs2_unknown_node u;
 209 };
 210
 211 /* Data payload for device nodes. */
 212 union jffs2_device_node {
 213         jint16_t old;
 214         jint32_t new;
 215 };
 216
 217 #endif /* __LINUX_JFFS2_H__ */