LXR linux/fs/squashfs/squashfs

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