1 /* 2 * JFFS2 -- Journalling Flash File System, Version 2. 3 * 4 * Copyright (C) 2001 Red Hat, Inc. 5 * 6 * Created by David Woodhouse <dwmw2@cambridge.redhat.com> 7 * 8 * The original JFFS, from which the design for JFFS2 was derived, 9 * was designed and implemented by Axis Communications AB. 10 * 11 * The contents of this file are subject to the Red Hat eCos Public 12 * License Version 1.1 (the "Licence"); you may not use this file 13 * except in compliance with the Licence. You may obtain a copy of 14 * the Licence at http://www.redhat.com/ 15 * 16 * Software distributed under the Licence is distributed on an "AS IS" 17 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. 18 * See the Licence for the specific language governing rights and 19 * limitations under the Licence. 20 * 21 * The Original Code is JFFS2 - Journalling Flash File System, version 2 22 * 23 * Alternatively, the contents of this file may be used under the 24 * terms of the GNU General Public License version 2 (the "GPL"), in 25 * which case the provisions of the GPL are applicable instead of the 26 * above. If you wish to allow the use of your version of this file 27 * only under the terms of the GPL and not to allow others to use your 28 * version of this file under the RHEPL, indicate your decision by 29 * deleting the provisions above and replace them with the notice and 30 * other provisions required by the GPL. If you do not delete the 31 * provisions above, a recipient may use your version of this file 32 * under either the RHEPL or the GPL. 33 * 34 * $Id: jffs2.h,v 1.19 2001/10/09 13:20:23 dwmw2 Exp $ 35 * 36 */ 37 38 #ifndef __LINUX_JFFS2_H__ 39 #define __LINUX_JFFS2_H__ 40 41 #include <asm/types.h> 42 #define JFFS2_SUPER_MAGIC 0x72b6 43 44 /* Values we may expect to find in the 'magic' field */ 45 #define JFFS2_OLD_MAGIC_BITMASK 0x1984 46 #define JFFS2_MAGIC_BITMASK 0x1985 47 #define KSAMTIB_CIGAM_2SFFJ 0x5981 /* For detecting wrong-endian fs */ 48 #define JFFS2_EMPTY_BITMASK 0xffff 49 #define JFFS2_DIRTY_BITMASK 0x0000 50 51 /* We only allow a single char for length, and 0xFF is empty flash so 52 we don't want it confused with a real length. Hence max 254. 53 */ 54 #define JFFS2_MAX_NAME_LEN 254 55 56 /* How small can we sensibly write nodes? */ 57 #define JFFS2_MIN_DATA_LEN 128 58 59 #define JFFS2_COMPR_NONE 0x00 60 #define JFFS2_COMPR_ZERO 0x01 61 #define JFFS2_COMPR_RTIME 0x02 62 #define JFFS2_COMPR_RUBINMIPS 0x03 63 #define JFFS2_COMPR_COPY 0x04 64 #define JFFS2_COMPR_DYNRUBIN 0x05 65 #define JFFS2_COMPR_ZLIB 0x06 66 /* Compatibility flags. */ 67 #define JFFS2_COMPAT_MASK 0xc000 /* What do to if an unknown nodetype is found */ 68 #define JFFS2_NODE_ACCURATE 0x2000 69 /* INCOMPAT: Fail to mount the filesystem */ 70 #define JFFS2_FEATURE_INCOMPAT 0xc000 71 /* ROCOMPAT: Mount read-only */ 72 #define JFFS2_FEATURE_ROCOMPAT 0x8000 73 /* RWCOMPAT_COPY: Mount read/write, and copy the node when it's GC'd */ 74 #define JFFS2_FEATURE_RWCOMPAT_COPY 0x4000 75 /* RWCOMPAT_DELETE: Mount read/write, and delete the node when it's GC'd */ 76 #define JFFS2_FEATURE_RWCOMPAT_DELETE 0x0000 77 78 #define JFFS2_NODETYPE_DIRENT (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 1) 79 #define JFFS2_NODETYPE_INODE (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 2) 80 #define JFFS2_NODETYPE_CLEANMARKER (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 3) 81 82 // Maybe later... 83 //#define JFFS2_NODETYPE_CHECKPOINT (JFFS2_FEATURE_RWCOMPAT_DELETE | JFFS2_NODE_ACCURATE | 3) 84 //#define JFFS2_NODETYPE_OPTIONS (JFFS2_FEATURE_RWCOMPAT_COPY | JFFS2_NODE_ACCURATE | 4) 85 86 /* Same as the non_ECC versions, but with extra space for real 87 * ECC instead of just the checksum. For use on NAND flash 88 */ 89 //#define JFFS2_NODETYPE_DIRENT_ECC (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 5) 90 //#define JFFS2_NODETYPE_INODE_ECC (JFFS2_FEATURE_INCOMPAT | JFFS2_NODE_ACCURATE | 6) 91 92 #define JFFS2_INO_FLAG_PREREAD 1 /* Do read_inode() for this one at 93 mount time, don't wait for it to 94 happen later */ 95 #define JFFS2_INO_FLAG_USERCOMPR 2 /* User has requested a specific 96 compression type */ 97 98 99 struct jffs2_unknown_node 100 { 101 /* All start like this */ 102 __u16 magic; 103 __u16 nodetype; 104 __u32 totlen; /* So we can skip over nodes we don't grok */ 105 __u32 hdr_crc; 106 } __attribute__((packed)); 107 108 struct jffs2_raw_dirent 109 { 110 __u16 magic; 111 __u16 nodetype; /* == JFFS_NODETYPE_DIRENT */ 112 __u32 totlen; 113 __u32 hdr_crc; 114 __u32 pino; 115 __u32 version; 116 __u32 ino; /* == zero for unlink */ 117 __u32 mctime; 118 __u8 nsize; 119 __u8 type; 120 __u8 unused[2]; 121 __u32 node_crc; 122 __u32 name_crc; 123 __u8 name[0]; 124 } __attribute__((packed)); 125 126 /* The JFFS2 raw inode structure: Used for storage on physical media. */ 127 /* The uid, gid, atime, mtime and ctime members could be longer, but 128 are left like this for space efficiency. If and when people decide 129 they really need them extended, it's simple enough to add support for 130 a new type of raw node. 131 */ 132 struct jffs2_raw_inode 133 { 134 __u16 magic; /* A constant magic number. */ 135 __u16 nodetype; /* == JFFS_NODETYPE_INODE */ 136 __u32 totlen; /* Total length of this node (inc data, etc.) */ 137 __u32 hdr_crc; 138 __u32 ino; /* Inode number. */ 139 __u32 version; /* Version number. */ 140 __u32 mode; /* The file's type or mode. */ 141 __u16 uid; /* The file's owner. */ 142 __u16 gid; /* The file's group. */ 143 __u32 isize; /* Total resultant size of this inode (used for truncations) */ 144 __u32 atime; /* Last access time. */ 145 __u32 mtime; /* Last modification time. */ 146 __u32 ctime; /* Change time. */ 147 __u32 offset; /* Where to begin to write. */ 148 __u32 csize; /* (Compressed) data size */ 149 __u32 dsize; /* Size of the node's data. (after decompression) */ 150 __u8 compr; /* Compression algorithm used */ 151 __u8 usercompr; /* Compression algorithm requested by the user */ 152 __u16 flags; /* See JFFS2_INO_FLAG_* */ 153 __u32 data_crc; /* CRC for the (compressed) data. */ 154 __u32 node_crc; /* CRC for the raw inode (excluding data) */ 155 // __u8 data[dsize]; 156 } __attribute__((packed)); 157 158 union jffs2_node_union { 159 struct jffs2_raw_inode i; 160 struct jffs2_raw_dirent d; 161 struct jffs2_unknown_node u; 162 }; 163 164 #endif /* __LINUX_JFFS2_H__ */ 165