fs/squashfs/squashfs_fs.h

   1 #ifndef SQUASHFS_FS
   2 #define SQUASHFS_FS
   3 /*
   4  * Squashfs
   5  *
   6  * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
   7  * Phillip Lougher <phillip@lougher.demon.co.uk>
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License
  11  * as published by the Free Software Foundation; either version 2,
  12  * or (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  22  *
  23  * squashfs_fs.h
  24  */
  25
  26 #define SQUASHFS_CACHED_FRAGMENTS       CONFIG_SQUASHFS_FRAGMENT_CACHE_SIZE
  27 #define SQUASHFS_MAJOR                  4
  28 #define SQUASHFS_MINOR                  0
  29 #define SQUASHFS_START                  0
  30
  31 /* size of metadata (inode and directory) blocks */
  32 #define SQUASHFS_METADATA_SIZE          8192
  33 #define SQUASHFS_METADATA_LOG           13
  34
  35 /* default size of data blocks */
  36 #define SQUASHFS_FILE_SIZE              131072
  37 #define SQUASHFS_FILE_LOG               17
  38
  39 #define SQUASHFS_FILE_MAX_SIZE          1048576
  40 #define SQUASHFS_FILE_MAX_LOG           20
  41
  42 /* Max number of uids and gids */
  43 #define SQUASHFS_IDS                    65536
  44
  45 /* Max length of filename (not 255) */
  46 #define SQUASHFS_NAME_LEN               256
  47
  48 #define SQUASHFS_INVALID_FRAG           (0xffffffffU)
  49 #define SQUASHFS_INVALID_XATTR          (0xffffffffU)
  50 #define SQUASHFS_INVALID_BLK            (-1LL)
  51
  52 /* Filesystem flags */
  53 #define SQUASHFS_NOI                    0
  54 #define SQUASHFS_NOD                    1
  55 #define SQUASHFS_NOF                    3
  56 #define SQUASHFS_NO_FRAG                4
  57 #define SQUASHFS_ALWAYS_FRAG            5
  58 #define SQUASHFS_DUPLICATE              6
  59 #define SQUASHFS_EXPORT                 7
  60
  61 #define SQUASHFS_BIT(flag, bit)         ((flag >> bit) & 1)
  62
  63 #define SQUASHFS_UNCOMPRESSED_INODES(flags)     SQUASHFS_BIT(flags, \
  64                                                 SQUASHFS_NOI)
  65
  66 #define SQUASHFS_UNCOMPRESSED_DATA(flags)       SQUASHFS_BIT(flags, \
  67                                                 SQUASHFS_NOD)
  68
  69 #define SQUASHFS_UNCOMPRESSED_FRAGMENTS(flags)  SQUASHFS_BIT(flags, \
  70                                                 SQUASHFS_NOF)
  71
  72 #define SQUASHFS_NO_FRAGMENTS(flags)            SQUASHFS_BIT(flags, \
  73                                                 SQUASHFS_NO_FRAG)
  74
  75 #define SQUASHFS_ALWAYS_FRAGMENTS(flags)        SQUASHFS_BIT(flags, \
  76                                                 SQUASHFS_ALWAYS_FRAG)
  77
  78 #define SQUASHFS_DUPLICATES(flags)              SQUASHFS_BIT(flags, \
  79                                                 SQUASHFS_DUPLICATE)
  80
  81 #define SQUASHFS_EXPORTABLE(flags)              SQUASHFS_BIT(flags, \
  82                                                 SQUASHFS_EXPORT)
  83
  84 /* Max number of types and file types */
  85 #define SQUASHFS_DIR_TYPE               1
  86 #define SQUASHFS_REG_TYPE               2
  87 #define SQUASHFS_SYMLINK_TYPE           3
  88 #define SQUASHFS_BLKDEV_TYPE            4
  89 #define SQUASHFS_CHRDEV_TYPE            5
  90 #define SQUASHFS_FIFO_TYPE              6
  91 #define SQUASHFS_SOCKET_TYPE            7
  92 #define SQUASHFS_LDIR_TYPE              8
  93 #define SQUASHFS_LREG_TYPE              9
  94 #define SQUASHFS_LSYMLINK_TYPE          10
  95 #define SQUASHFS_LBLKDEV_TYPE           11
  96 #define SQUASHFS_LCHRDEV_TYPE           12
  97 #define SQUASHFS_LFIFO_TYPE             13
  98 #define SQUASHFS_LSOCKET_TYPE           14
  99
 100 /* Xattr types */
 101 #define SQUASHFS_XATTR_USER             0
 102 #define SQUASHFS_XATTR_TRUSTED          1
 103 #define SQUASHFS_XATTR_SECURITY         2
 104 #define SQUASHFS_XATTR_VALUE_OOL        256
 105 #define SQUASHFS_XATTR_PREFIX_MASK      0xff
 106
 107 /* Flag whether block is compressed or uncompressed, bit is set if block is
 108  * uncompressed */
 109 #define SQUASHFS_COMPRESSED_BIT         (1 << 15)
 110
 111 #define SQUASHFS_COMPRESSED_SIZE(B)     (((B) & ~SQUASHFS_COMPRESSED_BIT) ? \
 112                 (B) & ~SQUASHFS_COMPRESSED_BIT :  SQUASHFS_COMPRESSED_BIT)
 113
 114 #define SQUASHFS_COMPRESSED(B)          (!((B) & SQUASHFS_COMPRESSED_BIT))
 115
 116 #define SQUASHFS_COMPRESSED_BIT_BLOCK   (1 << 24)
 117
 118 #define SQUASHFS_COMPRESSED_SIZE_BLOCK(B)       ((B) & \
 119                                                 ~SQUASHFS_COMPRESSED_BIT_BLOCK)
 120
 121 #define SQUASHFS_COMPRESSED_BLOCK(B)    (!((B) & SQUASHFS_COMPRESSED_BIT_BLOCK))
 122
 123 /*
 124  * Inode number ops.  Inodes consist of a compressed block number, and an
 125  * uncompressed offset within that block
 126  */
 127 #define SQUASHFS_INODE_BLK(A)           ((unsigned int) ((A) >> 16))
 128
 129 #define SQUASHFS_INODE_OFFSET(A)        ((unsigned int) ((A) & 0xffff))
 130
 131 #define SQUASHFS_MKINODE(A, B)          ((long long)(((long long) (A)\
 132                                         << 16) + (B)))
 133
 134 /* Translate between VFS mode and squashfs mode */
 135 #define SQUASHFS_MODE(A)                ((A) & 0xfff)
 136
 137 /* fragment and fragment table defines */
 138 #define SQUASHFS_FRAGMENT_BYTES(A)      \
 139                                 ((A) * sizeof(struct squashfs_fragment_entry))
 140
 141 #define SQUASHFS_FRAGMENT_INDEX(A)      (SQUASHFS_FRAGMENT_BYTES(A) / \
 142                                         SQUASHFS_METADATA_SIZE)
 143
 144 #define SQUASHFS_FRAGMENT_INDEX_OFFSET(A)       (SQUASHFS_FRAGMENT_BYTES(A) % \
 145                                                 SQUASHFS_METADATA_SIZE)
 146
 147 #define SQUASHFS_FRAGMENT_INDEXES(A)    ((SQUASHFS_FRAGMENT_BYTES(A) + \
 148                                         SQUASHFS_METADATA_SIZE - 1) / \
 149                                         SQUASHFS_METADATA_SIZE)
 150
 151 #define SQUASHFS_FRAGMENT_INDEX_BYTES(A)        (SQUASHFS_FRAGMENT_INDEXES(A) *\
 152                                                 sizeof(u64))
 153
 154 /* inode lookup table defines */
 155 #define SQUASHFS_LOOKUP_BYTES(A)        ((A) * sizeof(u64))
 156
 157 #define SQUASHFS_LOOKUP_BLOCK(A)        (SQUASHFS_LOOKUP_BYTES(A) / \
 158                                         SQUASHFS_METADATA_SIZE)
 159
 160 #define SQUASHFS_LOOKUP_BLOCK_OFFSET(A) (SQUASHFS_LOOKUP_BYTES(A) % \
 161                                         SQUASHFS_METADATA_SIZE)
 162
 163 #define SQUASHFS_LOOKUP_BLOCKS(A)       ((SQUASHFS_LOOKUP_BYTES(A) + \
 164                                         SQUASHFS_METADATA_SIZE - 1) / \
 165                                         SQUASHFS_METADATA_SIZE)
 166
 167 #define SQUASHFS_LOOKUP_BLOCK_BYTES(A)  (SQUASHFS_LOOKUP_BLOCKS(A) *\
 168                                         sizeof(u64))
 169
 170 /* uid/gid lookup table defines */
 171 #define SQUASHFS_ID_BYTES(A)            ((A) * sizeof(unsigned int))
 172
 173 #define SQUASHFS_ID_BLOCK(A)            (SQUASHFS_ID_BYTES(A) / \
 174                                         SQUASHFS_METADATA_SIZE)
 175
 176 #define SQUASHFS_ID_BLOCK_OFFSET(A)     (SQUASHFS_ID_BYTES(A) % \
 177                                         SQUASHFS_METADATA_SIZE)
 178
 179 #define SQUASHFS_ID_BLOCKS(A)           ((SQUASHFS_ID_BYTES(A) + \
 180                                         SQUASHFS_METADATA_SIZE - 1) / \
 181                                         SQUASHFS_METADATA_SIZE)
 182
 183 #define SQUASHFS_ID_BLOCK_BYTES(A)      (SQUASHFS_ID_BLOCKS(A) *\
 184                                         sizeof(u64))
 185 /* xattr id lookup table defines */
 186 #define SQUASHFS_XATTR_BYTES(A)         ((A) * sizeof(struct squashfs_xattr_id))
 187
 188 #define SQUASHFS_XATTR_BLOCK(A)         (SQUASHFS_XATTR_BYTES(A) / \
 189                                         SQUASHFS_METADATA_SIZE)
 190
 191 #define SQUASHFS_XATTR_BLOCK_OFFSET(A)  (SQUASHFS_XATTR_BYTES(A) % \
 192                                         SQUASHFS_METADATA_SIZE)
 193
 194 #define SQUASHFS_XATTR_BLOCKS(A)        ((SQUASHFS_XATTR_BYTES(A) + \
 195                                         SQUASHFS_METADATA_SIZE - 1) / \
 196                                         SQUASHFS_METADATA_SIZE)
 197
 198 #define SQUASHFS_XATTR_BLOCK_BYTES(A)   (SQUASHFS_XATTR_BLOCKS(A) *\
 199                                         sizeof(u64))
 200 #define SQUASHFS_XATTR_BLK(A)           ((unsigned int) ((A) >> 16))
 201
 202 #define SQUASHFS_XATTR_OFFSET(A)        ((unsigned int) ((A) & 0xffff))
 203
 204 /* cached data constants for filesystem */
 205 #define SQUASHFS_CACHED_BLKS            8
 206
 207 #define SQUASHFS_MAX_FILE_SIZE_LOG      64
 208
 209 #define SQUASHFS_MAX_FILE_SIZE          (1LL << \
 210                                         (SQUASHFS_MAX_FILE_SIZE_LOG - 2))
 211
 212 /* meta index cache */
 213 #define SQUASHFS_META_INDEXES   (SQUASHFS_METADATA_SIZE / sizeof(unsigned int))
 214 #define SQUASHFS_META_ENTRIES   127
 215 #define SQUASHFS_META_SLOTS     8
 216
 217 struct meta_entry {
 218         u64                     data_block;
 219         unsigned int            index_block;
 220         unsigned short          offset;
 221         unsigned short          pad;
 222 };
 223
 224 struct meta_index {
 225         unsigned int            inode_number;
 226         unsigned int            offset;
 227         unsigned short          entries;
 228         unsigned short          skip;
 229         unsigned short          locked;
 230         unsigned short          pad;
 231         struct meta_entry       meta_entry[SQUASHFS_META_ENTRIES];
 232 };
 233
 234
 235 /*
 236  * definitions for structures on disk
 237  */
 238 #define ZLIB_COMPRESSION        1
 239 #define LZMA_COMPRESSION        2
 240 #define LZO_COMPRESSION         3
 241
 242 struct squashfs_super_block {
 243         __le32                  s_magic;
 244         __le32                  inodes;
 245         __le32                  mkfs_time;
 246         __le32                  block_size;
 247         __le32                  fragments;
 248         __le16                  compression;
 249         __le16                  block_log;
 250         __le16                  flags;
 251         __le16                  no_ids;
 252         __le16                  s_major;
 253         __le16                  s_minor;
 254         __le64                  root_inode;
 255         __le64                  bytes_used;
 256         __le64                  id_table_start;
 257         __le64                  xattr_id_table_start;
 258         __le64                  inode_table_start;
 259         __le64                  directory_table_start;
 260         __le64                  fragment_table_start;
 261         __le64                  lookup_table_start;
 262 };
 263
 264 struct squashfs_dir_index {
 265         __le32                  index;
 266         __le32                  start_block;
 267         __le32                  size;
 268         unsigned char           name[0];
 269 };
 270
 271 struct squashfs_base_inode {
 272         __le16                  inode_type;
 273         __le16                  mode;
 274         __le16                  uid;
 275         __le16                  guid;
 276         __le32                  mtime;
 277         __le32                  inode_number;
 278 };
 279
 280 struct squashfs_ipc_inode {
 281         __le16                  inode_type;
 282         __le16                  mode;
 283         __le16                  uid;
 284         __le16                  guid;
 285         __le32                  mtime;
 286         __le32                  inode_number;
 287         __le32                  nlink;
 288 };
 289
 290 struct squashfs_dev_inode {
 291         __le16                  inode_type;
 292         __le16                  mode;
 293         __le16                  uid;
 294         __le16                  guid;
 295         __le32                  mtime;
 296         __le32                  inode_number;
 297         __le32                  nlink;
 298         __le32                  rdev;
 299 };
 300
 301 struct squashfs_symlink_inode {
 302         __le16                  inode_type;
 303         __le16                  mode;
 304         __le16                  uid;
 305         __le16                  guid;
 306         __le32                  mtime;
 307         __le32                  inode_number;
 308         __le32                  nlink;
 309         __le32                  symlink_size;
 310         char                    symlink[0];
 311 };
 312
 313 struct squashfs_reg_inode {
 314         __le16                  inode_type;
 315         __le16                  mode;
 316         __le16                  uid;
 317         __le16                  guid;
 318         __le32                  mtime;
 319         __le32                  inode_number;
 320         __le32                  start_block;
 321         __le32                  fragment;
 322         __le32                  offset;
 323         __le32                  file_size;
 324         __le16                  block_list[0];
 325 };
 326
 327 struct squashfs_lreg_inode {
 328         __le16                  inode_type;
 329         __le16                  mode;
 330         __le16                  uid;
 331         __le16                  guid;
 332         __le32                  mtime;
 333         __le32                  inode_number;
 334         __le64                  start_block;
 335         __le64                  file_size;
 336         __le64                  sparse;
 337         __le32                  nlink;
 338         __le32                  fragment;
 339         __le32                  offset;
 340         __le32                  xattr;
 341         __le16                  block_list[0];
 342 };
 343
 344 struct squashfs_dir_inode {
 345         __le16                  inode_type;
 346         __le16                  mode;
 347         __le16                  uid;
 348         __le16                  guid;
 349         __le32                  mtime;
 350         __le32                  inode_number;
 351         __le32                  start_block;
 352         __le32                  nlink;
 353         __le16                  file_size;
 354         __le16                  offset;
 355         __le32                  parent_inode;
 356 };
 357
 358 struct squashfs_ldir_inode {
 359         __le16                  inode_type;
 360         __le16                  mode;
 361         __le16                  uid;
 362         __le16                  guid;
 363         __le32                  mtime;
 364         __le32                  inode_number;
 365         __le32                  nlink;
 366         __le32                  file_size;
 367         __le32                  start_block;
 368         __le32                  parent_inode;
 369         __le16                  i_count;
 370         __le16                  offset;
 371         __le32                  xattr;
 372         struct squashfs_dir_index       index[0];
 373 };
 374
 375 union squashfs_inode {
 376         struct squashfs_base_inode              base;
 377         struct squashfs_dev_inode               dev;
 378         struct squashfs_symlink_inode           symlink;
 379         struct squashfs_reg_inode               reg;
 380         struct squashfs_lreg_inode              lreg;
 381         struct squashfs_dir_inode               dir;
 382         struct squashfs_ldir_inode              ldir;
 383         struct squashfs_ipc_inode               ipc;
 384 };
 385
 386 struct squashfs_dir_entry {
 387         __le16                  offset;
 388         __le16                  inode_number;
 389         __le16                  type;
 390         __le16                  size;
 391         char                    name[0];
 392 };
 393
 394 struct squashfs_dir_header {
 395         __le32                  count;
 396         __le32                  start_block;
 397         __le32                  inode_number;
 398 };
 399
 400 struct squashfs_fragment_entry {
 401         __le64                  start_block;
 402         __le32                  size;
 403         unsigned int            unused;
 404 };
 405
 406 struct squashfs_xattr_entry {
 407         __le16                  type;
 408         __le16                  size;
 409         char                    data[0];
 410 };
 411
 412 struct squashfs_xattr_val {
 413         __le32                  vsize;
 414         char                    value[0];
 415 };
 416
 417 struct squashfs_xattr_id {
 418         __le64                  xattr;
 419         __le32                  count;
 420         __le32                  size;
 421 };
 422
 423 struct squashfs_xattr_id_table {
 424         __le64                  xattr_table_start;
 425         __le32                  xattr_ids;
 426         __le32                  unused;
 427 };
 428
 429 #endif