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