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  *
  12  */
  13
  14 #ifndef __LINUX_JFFS2_H__
  15 #define __LINUX_JFFS2_H__
  16
  17 #define JFFS2_SUPER_MAGIC   0x72b6
  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 /* 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 #define JFFS2_NODETYPE_SUMMARY (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 6)
  66
  67 #define JFFS2_NODETYPE_XATTR (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 8)
  68 #define JFFS2_NODETYPE_XREF (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 9)
  69
  70 /* XATTR Related */
  71 #define JFFS2_XPREFIX_USER              1       /* for "user." */
  72 #define JFFS2_XPREFIX_SECURITY          2       /* for "security." */
  73 #define JFFS2_XPREFIX_ACL_ACCESS        3       /* for "system.posix_acl_access" */
  74 #define JFFS2_XPREFIX_ACL_DEFAULT       4       /* for "system.posix_acl_default" */
  75 #define JFFS2_XPREFIX_TRUSTED           5       /* for "trusted.*" */
  76
  77 #define JFFS2_ACL_VERSION               0x0001
  78
  79 // Maybe later...
  80 //#define JFFS2_NODETYPE_CHECKPOINT (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 3)
  81 //#define JFFS2_NODETYPE_OPTIONS (JFFS2_FEATURE_RWCOMPAT_COPY | JFFS2_NODE_ACCURATE | 4)
  82
  83
  84 #define JFFS2_INO_FLAG_PREREAD    1     /* Do read_inode() for this one at
  85                                            mount time, don't wait for it to
  86                                            happen later */
  87 #define JFFS2_INO_FLAG_USERCOMPR  2     /* User has requested a specific
  88                                            compression type */
  89
  90
  91 /* These can go once we've made sure we've caught all uses without
  92    byteswapping */
  93
  94 typedef uint32_t jint32_t;
  95
  96 typedef uint32_t jmode_t;
  97
  98 typedef uint16_t jint16_t;
  99
 100 struct jffs2_unknown_node
 101 {
 102         /* All start like this */
 103         jint16_t magic;
 104         jint16_t nodetype;
 105         jint32_t totlen; /* So we can skip over nodes we don't grok */
 106         jint32_t hdr_crc;
 107 };
 108
 109 struct jffs2_raw_dirent
 110 {
 111         jint16_t magic;
 112         jint16_t nodetype;      /* == JFFS2_NODETYPE_DIRENT */
 113         jint32_t totlen;
 114         jint32_t hdr_crc;
 115         jint32_t pino;
 116         jint32_t version;
 117         jint32_t ino; /* == zero for unlink */
 118         jint32_t mctime;
 119         uint8_t nsize;
 120         uint8_t type;
 121         uint8_t unused[2];
 122         jint32_t node_crc;
 123         jint32_t name_crc;
 124         uint8_t name[0];
 125 };
 126
 127 /* The JFFS2 raw inode structure: Used for storage on physical media.  */
 128 /* The uid, gid, atime, mtime and ctime members could be longer, but
 129    are left like this for space efficiency. If and when people decide
 130    they really need them extended, it's simple enough to add support for
 131    a new type of raw node.
 132 */
 133 struct jffs2_raw_inode
 134 {
 135         jint16_t magic;      /* A constant magic number.  */
 136         jint16_t nodetype;   /* == JFFS2_NODETYPE_INODE */
 137         jint32_t totlen;     /* Total length of this node (inc data, etc.) */
 138         jint32_t hdr_crc;
 139         jint32_t ino;        /* Inode number.  */
 140         jint32_t version;    /* Version number.  */
 141         jmode_t mode;       /* The file's type or mode.  */
 142         jint16_t uid;        /* The file's owner.  */
 143         jint16_t gid;        /* The file's group.  */
 144         jint32_t isize;      /* Total resultant size of this inode (used for truncations)  */
 145         jint32_t atime;      /* Last access time.  */
 146         jint32_t mtime;      /* Last modification time.  */
 147         jint32_t ctime;      /* Change time.  */
 148         jint32_t offset;     /* Where to begin to write.  */
 149         jint32_t csize;      /* (Compressed) data size */
 150         jint32_t dsize;      /* Size of the node's data. (after decompression) */
 151         uint8_t compr;       /* Compression algorithm used */
 152         uint8_t usercompr;   /* Compression algorithm requested by the user */
 153         jint16_t flags;      /* See JFFS2_INO_FLAG_* */
 154         jint32_t data_crc;   /* CRC for the (compressed) data.  */
 155         jint32_t node_crc;   /* CRC for the raw inode (excluding data)  */
 156         uint8_t data[0];
 157 };
 158
 159 struct jffs2_raw_xattr {
 160         jint16_t magic;
 161         jint16_t nodetype;      /* = JFFS2_NODETYPE_XATTR */
 162         jint32_t totlen;
 163         jint32_t hdr_crc;
 164         jint32_t xid;           /* XATTR identifier number */
 165         jint32_t version;
 166         uint8_t xprefix;
 167         uint8_t name_len;
 168         jint16_t value_len;
 169         jint32_t data_crc;
 170         jint32_t node_crc;
 171         uint8_t data[0];
 172 } __attribute__((packed));
 173
 174 struct jffs2_raw_xref
 175 {
 176         jint16_t magic;
 177         jint16_t nodetype;      /* = JFFS2_NODETYPE_XREF */
 178         jint32_t totlen;
 179         jint32_t hdr_crc;
 180         jint32_t ino;           /* inode number */
 181         jint32_t xid;           /* XATTR identifier number */
 182         jint32_t xseqno;        /* xref sequencial number */
 183         jint32_t node_crc;
 184 } __attribute__((packed));
 185
 186 struct jffs2_raw_summary
 187 {
 188         jint16_t magic;
 189         jint16_t nodetype;      /* = JFFS2_NODETYPE_SUMMARY */
 190         jint32_t totlen;
 191         jint32_t hdr_crc;
 192         jint32_t sum_num;       /* number of sum entries*/
 193         jint32_t cln_mkr;       /* clean marker size, 0 = no cleanmarker */
 194         jint32_t padded;        /* sum of the size of padding nodes */
 195         jint32_t sum_crc;       /* summary information crc */
 196         jint32_t node_crc;      /* node crc */
 197         jint32_t sum[0];        /* inode summary info */
 198 };
 199
 200 union jffs2_node_union
 201 {
 202         struct jffs2_raw_inode i;
 203         struct jffs2_raw_dirent d;
 204         struct jffs2_raw_xattr x;
 205         struct jffs2_raw_xref r;
 206         struct jffs2_raw_summary s;
 207         struct jffs2_unknown_node u;
 208 };
 209
 210 /* Data payload for device nodes. */
 211 union jffs2_device_node {
 212         jint16_t old;
 213         jint32_t new;
 214 };
 215
 216 #endif /* __LINUX_JFFS2_H__ */