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@squashfs.org.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 /* default size of block device I/O */
  40 #ifdef CONFIG_SQUASHFS_4K_DEVBLK_SIZE
  41 #define SQUASHFS_DEVBLK_SIZE 4096
  42 #else
  43 #define SQUASHFS_DEVBLK_SIZE 1024
  44 #endif
  45
  46 #define SQUASHFS_FILE_MAX_SIZE          1048576
  47 #define SQUASHFS_FILE_MAX_LOG           20
  48
  49 /* Max number of uids and gids */
  50 #define SQUASHFS_IDS                    65536
  51
  52 /* Max length of filename (not 255) */
  53 #define SQUASHFS_NAME_LEN               256
  54
  55 #define SQUASHFS_INVALID_FRAG           (0xffffffffU)
  56 #define SQUASHFS_INVALID_XATTR          (0xffffffffU)
  57 #define SQUASHFS_INVALID_BLK            (-1LL)
  58
  59 /* Filesystem flags */
  60 #define SQUASHFS_NOI                    0
  61 #define SQUASHFS_NOD                    1
  62 #define SQUASHFS_NOF                    3
  63 #define SQUASHFS_NO_FRAG                4
  64 #define SQUASHFS_ALWAYS_FRAG            5
  65 #define SQUASHFS_DUPLICATE              6
  66 #define SQUASHFS_EXPORT                 7
  67 #define SQUASHFS_COMP_OPT               10
  68
  69 #define SQUASHFS_BIT(flag, bit)         ((flag >> bit) & 1)
  70
  71 #define SQUASHFS_UNCOMPRESSED_INODES(flags)     SQUASHFS_BIT(flags, \
  72                                                 SQUASHFS_NOI)
  73
  74 #define SQUASHFS_UNCOMPRESSED_DATA(flags)       SQUASHFS_BIT(flags, \
  75                                                 SQUASHFS_NOD)
  76
  77 #define SQUASHFS_UNCOMPRESSED_FRAGMENTS(flags)  SQUASHFS_BIT(flags, \
  78                                                 SQUASHFS_NOF)
  79
  80 #define SQUASHFS_NO_FRAGMENTS(flags)            SQUASHFS_BIT(flags, \
  81                                                 SQUASHFS_NO_FRAG)
  82
  83 #define SQUASHFS_ALWAYS_FRAGMENTS(flags)        SQUASHFS_BIT(flags, \
  84                                                 SQUASHFS_ALWAYS_FRAG)
  85
  86 #define SQUASHFS_DUPLICATES(flags)              SQUASHFS_BIT(flags, \
  87                                                 SQUASHFS_DUPLICATE)
  88
  89 #define SQUASHFS_EXPORTABLE(flags)              SQUASHFS_BIT(flags, \
  90                                                 SQUASHFS_EXPORT)
  91
  92 #define SQUASHFS_COMP_OPTS(flags)               SQUASHFS_BIT(flags, \
  93                                                 SQUASHFS_COMP_OPT)
  94
  95 /* Max number of types and file types */
  96 #define SQUASHFS_DIR_TYPE               1
  97 #define SQUASHFS_REG_TYPE               2
  98 #define SQUASHFS_SYMLINK_TYPE           3
  99 #define SQUASHFS_BLKDEV_TYPE            4
 100 #define SQUASHFS_CHRDEV_TYPE            5
 101 #define SQUASHFS_FIFO_TYPE              6
 102 #define SQUASHFS_SOCKET_TYPE            7
 103 #define SQUASHFS_LDIR_TYPE              8
 104 #define SQUASHFS_LREG_TYPE              9
 105 #define SQUASHFS_LSYMLINK_TYPE          10
 106 #define SQUASHFS_LBLKDEV_TYPE           11
 107 #define SQUASHFS_LCHRDEV_TYPE           12
 108 #define SQUASHFS_LFIFO_TYPE             13
 109 #define SQUASHFS_LSOCKET_TYPE           14
 110
 111 /* Xattr types */
 112 #define SQUASHFS_XATTR_USER             0
 113 #define SQUASHFS_XATTR_TRUSTED          1
 114 #define SQUASHFS_XATTR_SECURITY         2
 115 #define SQUASHFS_XATTR_VALUE_OOL        256
 116 #define SQUASHFS_XATTR_PREFIX_MASK      0xff
 117
 118 /* Flag whether block is compressed or uncompressed, bit is set if block is
 119  * uncompressed */
 120 #define SQUASHFS_COMPRESSED_BIT         (1 << 15)
 121
 122 #define SQUASHFS_COMPRESSED_SIZE(B)     (((B) & ~SQUASHFS_COMPRESSED_BIT) ? \
 123                 (B) & ~SQUASHFS_COMPRESSED_BIT :  SQUASHFS_COMPRESSED_BIT)
 124
 125 #define SQUASHFS_COMPRESSED(B)          (!((B) & SQUASHFS_COMPRESSED_BIT))
 126
 127 #define SQUASHFS_COMPRESSED_BIT_BLOCK   (1 << 24)
 128
 129 #define SQUASHFS_COMPRESSED_SIZE_BLOCK(B)       ((B) & \
 130                                                 ~SQUASHFS_COMPRESSED_BIT_BLOCK)
 131
 132 #define SQUASHFS_COMPRESSED_BLOCK(B)    (!((B) & SQUASHFS_COMPRESSED_BIT_BLOCK))
 133
 134 /*
 135  * Inode number ops.  Inodes consist of a compressed block number, and an
 136  * uncompressed offset within that block
 137  */
 138 #define SQUASHFS_INODE_BLK(A)           ((unsigned int) ((A) >> 16))
 139
 140 #define SQUASHFS_INODE_OFFSET(A)        ((unsigned int) ((A) & 0xffff))
 141
 142 #define SQUASHFS_MKINODE(A, B)          ((long long)(((long long) (A)\
 143                                         << 16) + (B)))
 144
 145 /* Translate between VFS mode and squashfs mode */
 146 #define SQUASHFS_MODE(A)                ((A) & 0xfff)
 147
 148 /* fragment and fragment table defines */
 149 #define SQUASHFS_FRAGMENT_BYTES(A)      \
 150                                 ((A) * sizeof(struct squashfs_fragment_entry))
 151
 152 #define SQUASHFS_FRAGMENT_INDEX(A)      (SQUASHFS_FRAGMENT_BYTES(A) / \
 153                                         SQUASHFS_METADATA_SIZE)
 154
 155 #define SQUASHFS_FRAGMENT_INDEX_OFFSET(A)       (SQUASHFS_FRAGMENT_BYTES(A) % \
 156                                                 SQUASHFS_METADATA_SIZE)
 157
 158 #define SQUASHFS_FRAGMENT_INDEXES(A)    ((SQUASHFS_FRAGMENT_BYTES(A) + \
 159                                         SQUASHFS_METADATA_SIZE - 1) / \
 160                                         SQUASHFS_METADATA_SIZE)
 161
 162 #define SQUASHFS_FRAGMENT_INDEX_BYTES(A)        (SQUASHFS_FRAGMENT_INDEXES(A) *\
 163                                                 sizeof(u64))
 164
 165 /* inode lookup table defines */
 166 #define SQUASHFS_LOOKUP_BYTES(A)        ((A) * sizeof(u64))
 167
 168 #define SQUASHFS_LOOKUP_BLOCK(A)        (SQUASHFS_LOOKUP_BYTES(A) / \
 169                                         SQUASHFS_METADATA_SIZE)
 170
 171 #define SQUASHFS_LOOKUP_BLOCK_OFFSET(A) (SQUASHFS_LOOKUP_BYTES(A) % \
 172                                         SQUASHFS_METADATA_SIZE)
 173
 174 #define SQUASHFS_LOOKUP_BLOCKS(A)       ((SQUASHFS_LOOKUP_BYTES(A) + \
 175                                         SQUASHFS_METADATA_SIZE - 1) / \
 176                                         SQUASHFS_METADATA_SIZE)
 177
 178 #define SQUASHFS_LOOKUP_BLOCK_BYTES(A)  (SQUASHFS_LOOKUP_BLOCKS(A) *\
 179                                         sizeof(u64))
 180
 181 /* uid/gid lookup table defines */
 182 #define SQUASHFS_ID_BYTES(A)            ((A) * sizeof(unsigned int))
 183
 184 #define SQUASHFS_ID_BLOCK(A)            (SQUASHFS_ID_BYTES(A) / \
 185                                         SQUASHFS_METADATA_SIZE)
 186
 187 #define SQUASHFS_ID_BLOCK_OFFSET(A)     (SQUASHFS_ID_BYTES(A) % \
 188                                         SQUASHFS_METADATA_SIZE)
 189
 190 #define SQUASHFS_ID_BLOCKS(A)           ((SQUASHFS_ID_BYTES(A) + \
 191                                         SQUASHFS_METADATA_SIZE - 1) / \
 192                                         SQUASHFS_METADATA_SIZE)
 193
 194 #define SQUASHFS_ID_BLOCK_BYTES(A)      (SQUASHFS_ID_BLOCKS(A) *\
 195                                         sizeof(u64))
 196 /* xattr id lookup table defines */
 197 #define SQUASHFS_XATTR_BYTES(A)         ((A) * sizeof(struct squashfs_xattr_id))
 198
 199 #define SQUASHFS_XATTR_BLOCK(A)         (SQUASHFS_XATTR_BYTES(A) / \
 200                                         SQUASHFS_METADATA_SIZE)
 201
 202 #define SQUASHFS_XATTR_BLOCK_OFFSET(A)  (SQUASHFS_XATTR_BYTES(A) % \
 203                                         SQUASHFS_METADATA_SIZE)
 204
 205 #define SQUASHFS_XATTR_BLOCKS(A)        ((SQUASHFS_XATTR_BYTES(A) + \
 206                                         SQUASHFS_METADATA_SIZE - 1) / \
 207                                         SQUASHFS_METADATA_SIZE)
 208
 209 #define SQUASHFS_XATTR_BLOCK_BYTES(A)   (SQUASHFS_XATTR_BLOCKS(A) *\
 210                                         sizeof(u64))
 211 #define SQUASHFS_XATTR_BLK(A)           ((unsigned int) ((A) >> 16))
 212
 213 #define SQUASHFS_XATTR_OFFSET(A)        ((unsigned int) ((A) & 0xffff))
 214
 215 /* cached data constants for filesystem */
 216 #define SQUASHFS_CACHED_BLKS            8
 217
 218 #define SQUASHFS_MAX_FILE_SIZE_LOG      64
 219
 220 #define SQUASHFS_MAX_FILE_SIZE          (1LL << \
 221                                         (SQUASHFS_MAX_FILE_SIZE_LOG - 2))
 222
 223 /* meta index cache */
 224 #define SQUASHFS_META_INDEXES   (SQUASHFS_METADATA_SIZE / sizeof(unsigned int))
 225 #define SQUASHFS_META_ENTRIES   127
 226 #define SQUASHFS_META_SLOTS     8
 227
 228 struct meta_entry {
 229         u64                     data_block;
 230         unsigned int            index_block;
 231         unsigned short          offset;
 232         unsigned short          pad;
 233 };
 234
 235 struct meta_index {
 236         unsigned int            inode_number;
 237         unsigned int            offset;
 238         unsigned short          entries;
 239         unsigned short          skip;
 240         unsigned short          locked;
 241         unsigned short          pad;
 242         struct meta_entry       meta_entry[SQUASHFS_META_ENTRIES];
 243 };
 244
 245
 246 /*
 247  * definitions for structures on disk
 248  */
 249 #define ZLIB_COMPRESSION        1
 250 #define LZMA_COMPRESSION        2
 251 #define LZO_COMPRESSION         3
 252 #define XZ_COMPRESSION          4
 253
 254 struct squashfs_super_block {
 255         __le32                  s_magic;
 256         __le32                  inodes;
 257         __le32                  mkfs_time;
 258         __le32                  block_size;
 259         __le32                  fragments;
 260         __le16                  compression;
 261         __le16                  block_log;
 262         __le16                  flags;
 263         __le16                  no_ids;
 264         __le16                  s_major;
 265         __le16                  s_minor;
 266         __le64                  root_inode;
 267         __le64                  bytes_used;
 268         __le64                  id_table_start;
 269         __le64                  xattr_id_table_start;
 270         __le64                  inode_table_start;
 271         __le64                  directory_table_start;
 272         __le64                  fragment_table_start;
 273         __le64                  lookup_table_start;
 274 };
 275
 276 struct squashfs_dir_index {
 277         __le32                  index;
 278         __le32                  start_block;
 279         __le32                  size;
 280         unsigned char           name[0];
 281 };
 282
 283 struct squashfs_base_inode {
 284         __le16                  inode_type;
 285         __le16                  mode;
 286         __le16                  uid;
 287         __le16                  guid;
 288         __le32                  mtime;
 289         __le32                  inode_number;
 290 };
 291
 292 struct squashfs_ipc_inode {
 293         __le16                  inode_type;
 294         __le16                  mode;
 295         __le16                  uid;
 296         __le16                  guid;
 297         __le32                  mtime;
 298         __le32                  inode_number;
 299         __le32                  nlink;
 300 };
 301
 302 struct squashfs_lipc_inode {
 303         __le16                  inode_type;
 304         __le16                  mode;
 305         __le16                  uid;
 306         __le16                  guid;
 307         __le32                  mtime;
 308         __le32                  inode_number;
 309         __le32                  nlink;
 310         __le32                  xattr;
 311 };
 312
 313 struct squashfs_dev_inode {
 314         __le16                  inode_type;
 315         __le16                  mode;
 316         __le16                  uid;
 317         __le16                  guid;
 318         __le32                  mtime;
 319         __le32                  inode_number;
 320         __le32                  nlink;
 321         __le32                  rdev;
 322 };
 323
 324 struct squashfs_ldev_inode {
 325         __le16                  inode_type;
 326         __le16                  mode;
 327         __le16                  uid;
 328         __le16                  guid;
 329         __le32                  mtime;
 330         __le32                  inode_number;
 331         __le32                  nlink;
 332         __le32                  rdev;
 333         __le32                  xattr;
 334 };
 335
 336 struct squashfs_symlink_inode {
 337         __le16                  inode_type;
 338         __le16                  mode;
 339         __le16                  uid;
 340         __le16                  guid;
 341         __le32                  mtime;
 342         __le32                  inode_number;
 343         __le32                  nlink;
 344         __le32                  symlink_size;
 345         char                    symlink[0];
 346 };
 347
 348 struct squashfs_reg_inode {
 349         __le16                  inode_type;
 350         __le16                  mode;
 351         __le16                  uid;
 352         __le16                  guid;
 353         __le32                  mtime;
 354         __le32                  inode_number;
 355         __le32                  start_block;
 356         __le32                  fragment;
 357         __le32                  offset;
 358         __le32                  file_size;
 359         __le16                  block_list[0];
 360 };
 361
 362 struct squashfs_lreg_inode {
 363         __le16                  inode_type;
 364         __le16                  mode;
 365         __le16                  uid;
 366         __le16                  guid;
 367         __le32                  mtime;
 368         __le32                  inode_number;
 369         __le64                  start_block;
 370         __le64                  file_size;
 371         __le64                  sparse;
 372         __le32                  nlink;
 373         __le32                  fragment;
 374         __le32                  offset;
 375         __le32                  xattr;
 376         __le16                  block_list[0];
 377 };
 378
 379 struct squashfs_dir_inode {
 380         __le16                  inode_type;
 381         __le16                  mode;
 382         __le16                  uid;
 383         __le16                  guid;
 384         __le32                  mtime;
 385         __le32                  inode_number;
 386         __le32                  start_block;
 387         __le32                  nlink;
 388         __le16                  file_size;
 389         __le16                  offset;
 390         __le32                  parent_inode;
 391 };
 392
 393 struct squashfs_ldir_inode {
 394         __le16                  inode_type;
 395         __le16                  mode;
 396         __le16                  uid;
 397         __le16                  guid;
 398         __le32                  mtime;
 399         __le32                  inode_number;
 400         __le32                  nlink;
 401         __le32                  file_size;
 402         __le32                  start_block;
 403         __le32                  parent_inode;
 404         __le16                  i_count;
 405         __le16                  offset;
 406         __le32                  xattr;
 407         struct squashfs_dir_index       index[0];
 408 };
 409
 410 union squashfs_inode {
 411         struct squashfs_base_inode              base;
 412         struct squashfs_dev_inode               dev;
 413         struct squashfs_ldev_inode              ldev;
 414         struct squashfs_symlink_inode           symlink;
 415         struct squashfs_reg_inode               reg;
 416         struct squashfs_lreg_inode              lreg;
 417         struct squashfs_dir_inode               dir;
 418         struct squashfs_ldir_inode              ldir;
 419         struct squashfs_ipc_inode               ipc;
 420         struct squashfs_lipc_inode              lipc;
 421 };
 422
 423 struct squashfs_dir_entry {
 424         __le16                  offset;
 425         __le16                  inode_number;
 426         __le16                  type;
 427         __le16                  size;
 428         char                    name[0];
 429 };
 430
 431 struct squashfs_dir_header {
 432         __le32                  count;
 433         __le32                  start_block;
 434         __le32                  inode_number;
 435 };
 436
 437 struct squashfs_fragment_entry {
 438         __le64                  start_block;
 439         __le32                  size;
 440         unsigned int            unused;
 441 };
 442
 443 struct squashfs_xattr_entry {
 444         __le16                  type;
 445         __le16                  size;
 446         char                    data[0];
 447 };
 448
 449 struct squashfs_xattr_val {
 450         __le32                  vsize;
 451         char                    value[0];
 452 };
 453
 454 struct squashfs_xattr_id {
 455         __le64                  xattr;
 456         __le32                  count;
 457         __le32                  size;
 458 };
 459
 460 struct squashfs_xattr_id_table {
 461         __le64                  xattr_table_start;
 462         __le32                  xattr_ids;
 463         __le32                  unused;
 464 };
 465
 466 #endif