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 #define SQUASHFS_COMP_OPT               10
  61
  62 #define SQUASHFS_BIT(flag, bit)         ((flag >> bit) & 1)
  63
  64 #define SQUASHFS_UNCOMPRESSED_INODES(flags)     SQUASHFS_BIT(flags, \
  65                                                 SQUASHFS_NOI)
  66
  67 #define SQUASHFS_UNCOMPRESSED_DATA(flags)       SQUASHFS_BIT(flags, \
  68                                                 SQUASHFS_NOD)
  69
  70 #define SQUASHFS_UNCOMPRESSED_FRAGMENTS(flags)  SQUASHFS_BIT(flags, \
  71                                                 SQUASHFS_NOF)
  72
  73 #define SQUASHFS_NO_FRAGMENTS(flags)            SQUASHFS_BIT(flags, \
  74                                                 SQUASHFS_NO_FRAG)
  75
  76 #define SQUASHFS_ALWAYS_FRAGMENTS(flags)        SQUASHFS_BIT(flags, \
  77                                                 SQUASHFS_ALWAYS_FRAG)
  78
  79 #define SQUASHFS_DUPLICATES(flags)              SQUASHFS_BIT(flags, \
  80                                                 SQUASHFS_DUPLICATE)
  81
  82 #define SQUASHFS_EXPORTABLE(flags)              SQUASHFS_BIT(flags, \
  83                                                 SQUASHFS_EXPORT)
  84
  85 #define SQUASHFS_COMP_OPTS(flags)               SQUASHFS_BIT(flags, \
  86                                                 SQUASHFS_COMP_OPT)
  87
  88 /* Max number of types and file types */
  89 #define SQUASHFS_DIR_TYPE               1
  90 #define SQUASHFS_REG_TYPE               2
  91 #define SQUASHFS_SYMLINK_TYPE           3
  92 #define SQUASHFS_BLKDEV_TYPE            4
  93 #define SQUASHFS_CHRDEV_TYPE            5
  94 #define SQUASHFS_FIFO_TYPE              6
  95 #define SQUASHFS_SOCKET_TYPE            7
  96 #define SQUASHFS_LDIR_TYPE              8
  97 #define SQUASHFS_LREG_TYPE              9
  98 #define SQUASHFS_LSYMLINK_TYPE          10
  99 #define SQUASHFS_LBLKDEV_TYPE           11
 100 #define SQUASHFS_LCHRDEV_TYPE           12
 101 #define SQUASHFS_LFIFO_TYPE             13
 102 #define SQUASHFS_LSOCKET_TYPE           14
 103
 104 /* Xattr types */
 105 #define SQUASHFS_XATTR_USER             0
 106 #define SQUASHFS_XATTR_TRUSTED          1
 107 #define SQUASHFS_XATTR_SECURITY         2
 108 #define SQUASHFS_XATTR_VALUE_OOL        256
 109 #define SQUASHFS_XATTR_PREFIX_MASK      0xff
 110
 111 /* Flag whether block is compressed or uncompressed, bit is set if block is
 112  * uncompressed */
 113 #define SQUASHFS_COMPRESSED_BIT         (1 << 15)
 114
 115 #define SQUASHFS_COMPRESSED_SIZE(B)     (((B) & ~SQUASHFS_COMPRESSED_BIT) ? \
 116                 (B) & ~SQUASHFS_COMPRESSED_BIT :  SQUASHFS_COMPRESSED_BIT)
 117
 118 #define SQUASHFS_COMPRESSED(B)          (!((B) & SQUASHFS_COMPRESSED_BIT))
 119
 120 #define SQUASHFS_COMPRESSED_BIT_BLOCK   (1 << 24)
 121
 122 #define SQUASHFS_COMPRESSED_SIZE_BLOCK(B)       ((B) & \
 123                                                 ~SQUASHFS_COMPRESSED_BIT_BLOCK)
 124
 125 #define SQUASHFS_COMPRESSED_BLOCK(B)    (!((B) & SQUASHFS_COMPRESSED_BIT_BLOCK))
 126
 127 /*
 128  * Inode number ops.  Inodes consist of a compressed block number, and an
 129  * uncompressed offset within that block
 130  */
 131 #define SQUASHFS_INODE_BLK(A)           ((unsigned int) ((A) >> 16))
 132
 133 #define SQUASHFS_INODE_OFFSET(A)        ((unsigned int) ((A) & 0xffff))
 134
 135 #define SQUASHFS_MKINODE(A, B)          ((long long)(((long long) (A)\
 136                                         << 16) + (B)))
 137
 138 /* Translate between VFS mode and squashfs mode */
 139 #define SQUASHFS_MODE(A)                ((A) & 0xfff)
 140
 141 /* fragment and fragment table defines */
 142 #define SQUASHFS_FRAGMENT_BYTES(A)      \
 143                                 ((A) * sizeof(struct squashfs_fragment_entry))
 144
 145 #define SQUASHFS_FRAGMENT_INDEX(A)      (SQUASHFS_FRAGMENT_BYTES(A) / \
 146                                         SQUASHFS_METADATA_SIZE)
 147
 148 #define SQUASHFS_FRAGMENT_INDEX_OFFSET(A)       (SQUASHFS_FRAGMENT_BYTES(A) % \
 149                                                 SQUASHFS_METADATA_SIZE)
 150
 151 #define SQUASHFS_FRAGMENT_INDEXES(A)    ((SQUASHFS_FRAGMENT_BYTES(A) + \
 152                                         SQUASHFS_METADATA_SIZE - 1) / \
 153                                         SQUASHFS_METADATA_SIZE)
 154
 155 #define SQUASHFS_FRAGMENT_INDEX_BYTES(A)        (SQUASHFS_FRAGMENT_INDEXES(A) *\
 156                                                 sizeof(u64))
 157
 158 /* inode lookup table defines */
 159 #define SQUASHFS_LOOKUP_BYTES(A)        ((A) * sizeof(u64))
 160
 161 #define SQUASHFS_LOOKUP_BLOCK(A)        (SQUASHFS_LOOKUP_BYTES(A) / \
 162                                         SQUASHFS_METADATA_SIZE)
 163
 164 #define SQUASHFS_LOOKUP_BLOCK_OFFSET(A) (SQUASHFS_LOOKUP_BYTES(A) % \
 165                                         SQUASHFS_METADATA_SIZE)
 166
 167 #define SQUASHFS_LOOKUP_BLOCKS(A)       ((SQUASHFS_LOOKUP_BYTES(A) + \
 168                                         SQUASHFS_METADATA_SIZE - 1) / \
 169                                         SQUASHFS_METADATA_SIZE)
 170
 171 #define SQUASHFS_LOOKUP_BLOCK_BYTES(A)  (SQUASHFS_LOOKUP_BLOCKS(A) *\
 172                                         sizeof(u64))
 173
 174 /* uid/gid lookup table defines */
 175 #define SQUASHFS_ID_BYTES(A)            ((A) * sizeof(unsigned int))
 176
 177 #define SQUASHFS_ID_BLOCK(A)            (SQUASHFS_ID_BYTES(A) / \
 178                                         SQUASHFS_METADATA_SIZE)
 179
 180 #define SQUASHFS_ID_BLOCK_OFFSET(A)     (SQUASHFS_ID_BYTES(A) % \
 181                                         SQUASHFS_METADATA_SIZE)
 182
 183 #define SQUASHFS_ID_BLOCKS(A)           ((SQUASHFS_ID_BYTES(A) + \
 184                                         SQUASHFS_METADATA_SIZE - 1) / \
 185                                         SQUASHFS_METADATA_SIZE)
 186
 187 #define SQUASHFS_ID_BLOCK_BYTES(A)      (SQUASHFS_ID_BLOCKS(A) *\
 188                                         sizeof(u64))
 189 /* xattr id lookup table defines */
 190 #define SQUASHFS_XATTR_BYTES(A)         ((A) * sizeof(struct squashfs_xattr_id))
 191
 192 #define SQUASHFS_XATTR_BLOCK(A)         (SQUASHFS_XATTR_BYTES(A) / \
 193                                         SQUASHFS_METADATA_SIZE)
 194
 195 #define SQUASHFS_XATTR_BLOCK_OFFSET(A)  (SQUASHFS_XATTR_BYTES(A) % \
 196                                         SQUASHFS_METADATA_SIZE)
 197
 198 #define SQUASHFS_XATTR_BLOCKS(A)        ((SQUASHFS_XATTR_BYTES(A) + \
 199                                         SQUASHFS_METADATA_SIZE - 1) / \
 200                                         SQUASHFS_METADATA_SIZE)
 201
 202 #define SQUASHFS_XATTR_BLOCK_BYTES(A)   (SQUASHFS_XATTR_BLOCKS(A) *\
 203                                         sizeof(u64))
 204 #define SQUASHFS_XATTR_BLK(A)           ((unsigned int) ((A) >> 16))
 205
 206 #define SQUASHFS_XATTR_OFFSET(A)        ((unsigned int) ((A) & 0xffff))
 207
 208 /* cached data constants for filesystem */
 209 #define SQUASHFS_CACHED_BLKS            8
 210
 211 #define SQUASHFS_MAX_FILE_SIZE_LOG      64
 212
 213 #define SQUASHFS_MAX_FILE_SIZE          (1LL << \
 214                                         (SQUASHFS_MAX_FILE_SIZE_LOG - 2))
 215
 216 /* meta index cache */
 217 #define SQUASHFS_META_INDEXES   (SQUASHFS_METADATA_SIZE / sizeof(unsigned int))
 218 #define SQUASHFS_META_ENTRIES   127
 219 #define SQUASHFS_META_SLOTS     8
 220
 221 struct meta_entry {
 222         u64                     data_block;
 223         unsigned int            index_block;
 224         unsigned short          offset;
 225         unsigned short          pad;
 226 };
 227
 228 struct meta_index {
 229         unsigned int            inode_number;
 230         unsigned int            offset;
 231         unsigned short          entries;
 232         unsigned short          skip;
 233         unsigned short          locked;
 234         unsigned short          pad;
 235         struct meta_entry       meta_entry[SQUASHFS_META_ENTRIES];
 236 };
 237
 238
 239 /*
 240  * definitions for structures on disk
 241  */
 242 #define ZLIB_COMPRESSION        1
 243 #define LZMA_COMPRESSION        2
 244 #define LZO_COMPRESSION         3
 245 #define XZ_COMPRESSION          4
 246
 247 struct squashfs_super_block {
 248         __le32                  s_magic;
 249         __le32                  inodes;
 250         __le32                  mkfs_time;
 251         __le32                  block_size;
 252         __le32                  fragments;
 253         __le16                  compression;
 254         __le16                  block_log;
 255         __le16                  flags;
 256         __le16                  no_ids;
 257         __le16                  s_major;
 258         __le16                  s_minor;
 259         __le64                  root_inode;
 260         __le64                  bytes_used;
 261         __le64                  id_table_start;
 262         __le64                  xattr_id_table_start;
 263         __le64                  inode_table_start;
 264         __le64                  directory_table_start;
 265         __le64                  fragment_table_start;
 266         __le64                  lookup_table_start;
 267 };
 268
 269 struct squashfs_dir_index {
 270         __le32                  index;
 271         __le32                  start_block;
 272         __le32                  size;
 273         unsigned char           name[0];
 274 };
 275
 276 struct squashfs_base_inode {
 277         __le16                  inode_type;
 278         __le16                  mode;
 279         __le16                  uid;
 280         __le16                  guid;
 281         __le32                  mtime;
 282         __le32                  inode_number;
 283 };
 284
 285 struct squashfs_ipc_inode {
 286         __le16                  inode_type;
 287         __le16                  mode;
 288         __le16                  uid;
 289         __le16                  guid;
 290         __le32                  mtime;
 291         __le32                  inode_number;
 292         __le32                  nlink;
 293 };
 294
 295 struct squashfs_lipc_inode {
 296         __le16                  inode_type;
 297         __le16                  mode;
 298         __le16                  uid;
 299         __le16                  guid;
 300         __le32                  mtime;
 301         __le32                  inode_number;
 302         __le32                  nlink;
 303         __le32                  xattr;
 304 };
 305
 306 struct squashfs_dev_inode {
 307         __le16                  inode_type;
 308         __le16                  mode;
 309         __le16                  uid;
 310         __le16                  guid;
 311         __le32                  mtime;
 312         __le32                  inode_number;
 313         __le32                  nlink;
 314         __le32                  rdev;
 315 };
 316
 317 struct squashfs_ldev_inode {
 318         __le16                  inode_type;
 319         __le16                  mode;
 320         __le16                  uid;
 321         __le16                  guid;
 322         __le32                  mtime;
 323         __le32                  inode_number;
 324         __le32                  nlink;
 325         __le32                  rdev;
 326         __le32                  xattr;
 327 };
 328
 329 struct squashfs_symlink_inode {
 330         __le16                  inode_type;
 331         __le16                  mode;
 332         __le16                  uid;
 333         __le16                  guid;
 334         __le32                  mtime;
 335         __le32                  inode_number;
 336         __le32                  nlink;
 337         __le32                  symlink_size;
 338         char                    symlink[0];
 339 };
 340
 341 struct squashfs_reg_inode {
 342         __le16                  inode_type;
 343         __le16                  mode;
 344         __le16                  uid;
 345         __le16                  guid;
 346         __le32                  mtime;
 347         __le32                  inode_number;
 348         __le32                  start_block;
 349         __le32                  fragment;
 350         __le32                  offset;
 351         __le32                  file_size;
 352         __le16                  block_list[0];
 353 };
 354
 355 struct squashfs_lreg_inode {
 356         __le16                  inode_type;
 357         __le16                  mode;
 358         __le16                  uid;
 359         __le16                  guid;
 360         __le32                  mtime;
 361         __le32                  inode_number;
 362         __le64                  start_block;
 363         __le64                  file_size;
 364         __le64                  sparse;
 365         __le32                  nlink;
 366         __le32                  fragment;
 367         __le32                  offset;
 368         __le32                  xattr;
 369         __le16                  block_list[0];
 370 };
 371
 372 struct squashfs_dir_inode {
 373         __le16                  inode_type;
 374         __le16                  mode;
 375         __le16                  uid;
 376         __le16                  guid;
 377         __le32                  mtime;
 378         __le32                  inode_number;
 379         __le32                  start_block;
 380         __le32                  nlink;
 381         __le16                  file_size;
 382         __le16                  offset;
 383         __le32                  parent_inode;
 384 };
 385
 386 struct squashfs_ldir_inode {
 387         __le16                  inode_type;
 388         __le16                  mode;
 389         __le16                  uid;
 390         __le16                  guid;
 391         __le32                  mtime;
 392         __le32                  inode_number;
 393         __le32                  nlink;
 394         __le32                  file_size;
 395         __le32                  start_block;
 396         __le32                  parent_inode;
 397         __le16                  i_count;
 398         __le16                  offset;
 399         __le32                  xattr;
 400         struct squashfs_dir_index       index[0];
 401 };
 402
 403 union squashfs_inode {
 404         struct squashfs_base_inode              base;
 405         struct squashfs_dev_inode               dev;
 406         struct squashfs_ldev_inode              ldev;
 407         struct squashfs_symlink_inode           symlink;
 408         struct squashfs_reg_inode               reg;
 409         struct squashfs_lreg_inode              lreg;
 410         struct squashfs_dir_inode               dir;
 411         struct squashfs_ldir_inode              ldir;
 412         struct squashfs_ipc_inode               ipc;
 413         struct squashfs_lipc_inode              lipc;
 414 };
 415
 416 struct squashfs_dir_entry {
 417         __le16                  offset;
 418         __le16                  inode_number;
 419         __le16                  type;
 420         __le16                  size;
 421         char                    name[0];
 422 };
 423
 424 struct squashfs_dir_header {
 425         __le32                  count;
 426         __le32                  start_block;
 427         __le32                  inode_number;
 428 };
 429
 430 struct squashfs_fragment_entry {
 431         __le64                  start_block;
 432         __le32                  size;
 433         unsigned int            unused;
 434 };
 435
 436 struct squashfs_xattr_entry {
 437         __le16                  type;
 438         __le16                  size;
 439         char                    data[0];
 440 };
 441
 442 struct squashfs_xattr_val {
 443         __le32                  vsize;
 444         char                    value[0];
 445 };
 446
 447 struct squashfs_xattr_id {
 448         __le64                  xattr;
 449         __le32                  count;
 450         __le32                  size;
 451 };
 452
 453 struct squashfs_xattr_id_table {
 454         __le64                  xattr_table_start;
 455         __le32                  xattr_ids;
 456         __le32                  unused;
 457 };
 458
 459 #endif