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/* Inode types including extended 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/* Max type value stored in directory entry */
 107#define SQUASHFS_MAX_DIR_TYPE           7
 108
 109/* Xattr types */
 110#define SQUASHFS_XATTR_USER             0
 111#define SQUASHFS_XATTR_TRUSTED          1
 112#define SQUASHFS_XATTR_SECURITY         2
 113#define SQUASHFS_XATTR_VALUE_OOL        256
 114#define SQUASHFS_XATTR_PREFIX_MASK      0xff
 115
 116/* Flag whether block is compressed or uncompressed, bit is set if block is
 117 * uncompressed */
 118#define SQUASHFS_COMPRESSED_BIT         (1 << 15)
 119
 120#define SQUASHFS_COMPRESSED_SIZE(B)     (((B) & ~SQUASHFS_COMPRESSED_BIT) ? \
 121                (B) & ~SQUASHFS_COMPRESSED_BIT :  SQUASHFS_COMPRESSED_BIT)
 122
 123#define SQUASHFS_COMPRESSED(B)          (!((B) & SQUASHFS_COMPRESSED_BIT))
 124
 125#define SQUASHFS_COMPRESSED_BIT_BLOCK   (1 << 24)
 126
 127#define SQUASHFS_COMPRESSED_SIZE_BLOCK(B)       ((B) & \
 128                                                ~SQUASHFS_COMPRESSED_BIT_BLOCK)
 129
 130#define SQUASHFS_COMPRESSED_BLOCK(B)    (!((B) & SQUASHFS_COMPRESSED_BIT_BLOCK))
 131
 132/*
 133 * Inode number ops.  Inodes consist of a compressed block number, and an
 134 * uncompressed offset within that block
 135 */
 136#define SQUASHFS_INODE_BLK(A)           ((unsigned int) ((A) >> 16))
 137
 138#define SQUASHFS_INODE_OFFSET(A)        ((unsigned int) ((A) & 0xffff))
 139
 140#define SQUASHFS_MKINODE(A, B)          ((long long)(((long long) (A)\
 141                                        << 16) + (B)))
 142
 143/* fragment and fragment table defines */
 144#define SQUASHFS_FRAGMENT_BYTES(A)      \
 145                                ((A) * sizeof(struct squashfs_fragment_entry))
 146
 147#define SQUASHFS_FRAGMENT_INDEX(A)      (SQUASHFS_FRAGMENT_BYTES(A) / \
 148                                        SQUASHFS_METADATA_SIZE)
 149
 150#define SQUASHFS_FRAGMENT_INDEX_OFFSET(A)       (SQUASHFS_FRAGMENT_BYTES(A) % \
 151                                                SQUASHFS_METADATA_SIZE)
 152
 153#define SQUASHFS_FRAGMENT_INDEXES(A)    ((SQUASHFS_FRAGMENT_BYTES(A) + \
 154                                        SQUASHFS_METADATA_SIZE - 1) / \
 155                                        SQUASHFS_METADATA_SIZE)
 156
 157#define SQUASHFS_FRAGMENT_INDEX_BYTES(A)        (SQUASHFS_FRAGMENT_INDEXES(A) *\
 158                                                sizeof(u64))
 159
 160/* inode lookup table defines */
 161#define SQUASHFS_LOOKUP_BYTES(A)        ((A) * sizeof(u64))
 162
 163#define SQUASHFS_LOOKUP_BLOCK(A)        (SQUASHFS_LOOKUP_BYTES(A) / \
 164                                        SQUASHFS_METADATA_SIZE)
 165
 166#define SQUASHFS_LOOKUP_BLOCK_OFFSET(A) (SQUASHFS_LOOKUP_BYTES(A) % \
 167                                        SQUASHFS_METADATA_SIZE)
 168
 169#define SQUASHFS_LOOKUP_BLOCKS(A)       ((SQUASHFS_LOOKUP_BYTES(A) + \
 170                                        SQUASHFS_METADATA_SIZE - 1) / \
 171                                        SQUASHFS_METADATA_SIZE)
 172
 173#define SQUASHFS_LOOKUP_BLOCK_BYTES(A)  (SQUASHFS_LOOKUP_BLOCKS(A) *\
 174                                        sizeof(u64))
 175
 176/* uid/gid lookup table defines */
 177#define SQUASHFS_ID_BYTES(A)            ((A) * sizeof(unsigned int))
 178
 179#define SQUASHFS_ID_BLOCK(A)            (SQUASHFS_ID_BYTES(A) / \
 180                                        SQUASHFS_METADATA_SIZE)
 181
 182#define SQUASHFS_ID_BLOCK_OFFSET(A)     (SQUASHFS_ID_BYTES(A) % \
 183                                        SQUASHFS_METADATA_SIZE)
 184
 185#define SQUASHFS_ID_BLOCKS(A)           ((SQUASHFS_ID_BYTES(A) + \
 186                                        SQUASHFS_METADATA_SIZE - 1) / \
 187                                        SQUASHFS_METADATA_SIZE)
 188
 189#define SQUASHFS_ID_BLOCK_BYTES(A)      (SQUASHFS_ID_BLOCKS(A) *\
 190                                        sizeof(u64))
 191/* xattr id lookup table defines */
 192#define SQUASHFS_XATTR_BYTES(A)         ((A) * sizeof(struct squashfs_xattr_id))
 193
 194#define SQUASHFS_XATTR_BLOCK(A)         (SQUASHFS_XATTR_BYTES(A) / \
 195                                        SQUASHFS_METADATA_SIZE)
 196
 197#define SQUASHFS_XATTR_BLOCK_OFFSET(A)  (SQUASHFS_XATTR_BYTES(A) % \
 198                                        SQUASHFS_METADATA_SIZE)
 199
 200#define SQUASHFS_XATTR_BLOCKS(A)        ((SQUASHFS_XATTR_BYTES(A) + \
 201                                        SQUASHFS_METADATA_SIZE - 1) / \
 202                                        SQUASHFS_METADATA_SIZE)
 203
 204#define SQUASHFS_XATTR_BLOCK_BYTES(A)   (SQUASHFS_XATTR_BLOCKS(A) *\
 205                                        sizeof(u64))
 206#define SQUASHFS_XATTR_BLK(A)           ((unsigned int) ((A) >> 16))
 207
 208#define SQUASHFS_XATTR_OFFSET(A)        ((unsigned int) ((A) & 0xffff))
 209
 210/* cached data constants for filesystem */
 211#define SQUASHFS_CACHED_BLKS            8
 212
 213/* meta index cache */
 214#define SQUASHFS_META_INDEXES   (SQUASHFS_METADATA_SIZE / sizeof(unsigned int))
 215#define SQUASHFS_META_ENTRIES   127
 216#define SQUASHFS_META_SLOTS     8
 217
 218struct meta_entry {
 219        u64                     data_block;
 220        unsigned int            index_block;
 221        unsigned short          offset;
 222        unsigned short          pad;
 223};
 224
 225struct meta_index {
 226        unsigned int            inode_number;
 227        unsigned int            offset;
 228        unsigned short          entries;
 229        unsigned short          skip;
 230        unsigned short          locked;
 231        unsigned short          pad;
 232        struct meta_entry       meta_entry[SQUASHFS_META_ENTRIES];
 233};
 234
 235
 236/*
 237 * definitions for structures on disk
 238 */
 239#define ZLIB_COMPRESSION        1
 240#define LZMA_COMPRESSION        2
 241#define LZO_COMPRESSION         3
 242#define XZ_COMPRESSION          4
 243#define LZ4_COMPRESSION         5
 244#define ZSTD_COMPRESSION        6
 245
 246struct squashfs_super_block {
 247        __le32                  s_magic;
 248        __le32                  inodes;
 249        __le32                  mkfs_time;
 250        __le32                  block_size;
 251        __le32                  fragments;
 252        __le16                  compression;
 253        __le16                  block_log;
 254        __le16                  flags;
 255        __le16                  no_ids;
 256        __le16                  s_major;
 257        __le16                  s_minor;
 258        __le64                  root_inode;
 259        __le64                  bytes_used;
 260        __le64                  id_table_start;
 261        __le64                  xattr_id_table_start;
 262        __le64                  inode_table_start;
 263        __le64                  directory_table_start;
 264        __le64                  fragment_table_start;
 265        __le64                  lookup_table_start;
 266};
 267
 268struct squashfs_dir_index {
 269        __le32                  index;
 270        __le32                  start_block;
 271        __le32                  size;
 272        unsigned char           name[0];
 273};
 274
 275struct squashfs_base_inode {
 276        __le16                  inode_type;
 277        __le16                  mode;
 278        __le16                  uid;
 279        __le16                  guid;
 280        __le32                  mtime;
 281        __le32                  inode_number;
 282};
 283
 284struct squashfs_ipc_inode {
 285        __le16                  inode_type;
 286        __le16                  mode;
 287        __le16                  uid;
 288        __le16                  guid;
 289        __le32                  mtime;
 290        __le32                  inode_number;
 291        __le32                  nlink;
 292};
 293
 294struct squashfs_lipc_inode {
 295        __le16                  inode_type;
 296        __le16                  mode;
 297        __le16                  uid;
 298        __le16                  guid;
 299        __le32                  mtime;
 300        __le32                  inode_number;
 301        __le32                  nlink;
 302        __le32                  xattr;
 303};
 304
 305struct squashfs_dev_inode {
 306        __le16                  inode_type;
 307        __le16                  mode;
 308        __le16                  uid;
 309        __le16                  guid;
 310        __le32                  mtime;
 311        __le32                  inode_number;
 312        __le32                  nlink;
 313        __le32                  rdev;
 314};
 315
 316struct squashfs_ldev_inode {
 317        __le16                  inode_type;
 318        __le16                  mode;
 319        __le16                  uid;
 320        __le16                  guid;
 321        __le32                  mtime;
 322        __le32                  inode_number;
 323        __le32                  nlink;
 324        __le32                  rdev;
 325        __le32                  xattr;
 326};
 327
 328struct squashfs_symlink_inode {
 329        __le16                  inode_type;
 330        __le16                  mode;
 331        __le16                  uid;
 332        __le16                  guid;
 333        __le32                  mtime;
 334        __le32                  inode_number;
 335        __le32                  nlink;
 336        __le32                  symlink_size;
 337        char                    symlink[0];
 338};
 339
 340struct squashfs_reg_inode {
 341        __le16                  inode_type;
 342        __le16                  mode;
 343        __le16                  uid;
 344        __le16                  guid;
 345        __le32                  mtime;
 346        __le32                  inode_number;
 347        __le32                  start_block;
 348        __le32                  fragment;
 349        __le32                  offset;
 350        __le32                  file_size;
 351        __le16                  block_list[0];
 352};
 353
 354struct squashfs_lreg_inode {
 355        __le16                  inode_type;
 356        __le16                  mode;
 357        __le16                  uid;
 358        __le16                  guid;
 359        __le32                  mtime;
 360        __le32                  inode_number;
 361        __le64                  start_block;
 362        __le64                  file_size;
 363        __le64                  sparse;
 364        __le32                  nlink;
 365        __le32                  fragment;
 366        __le32                  offset;
 367        __le32                  xattr;
 368        __le16                  block_list[0];
 369};
 370
 371struct squashfs_dir_inode {
 372        __le16                  inode_type;
 373        __le16                  mode;
 374        __le16                  uid;
 375        __le16                  guid;
 376        __le32                  mtime;
 377        __le32                  inode_number;
 378        __le32                  start_block;
 379        __le32                  nlink;
 380        __le16                  file_size;
 381        __le16                  offset;
 382        __le32                  parent_inode;
 383};
 384
 385struct squashfs_ldir_inode {
 386        __le16                  inode_type;
 387        __le16                  mode;
 388        __le16                  uid;
 389        __le16                  guid;
 390        __le32                  mtime;
 391        __le32                  inode_number;
 392        __le32                  nlink;
 393        __le32                  file_size;
 394        __le32                  start_block;
 395        __le32                  parent_inode;
 396        __le16                  i_count;
 397        __le16                  offset;
 398        __le32                  xattr;
 399        struct squashfs_dir_index       index[0];
 400};
 401
 402union squashfs_inode {
 403        struct squashfs_base_inode              base;
 404        struct squashfs_dev_inode               dev;
 405        struct squashfs_ldev_inode              ldev;
 406        struct squashfs_symlink_inode           symlink;
 407        struct squashfs_reg_inode               reg;
 408        struct squashfs_lreg_inode              lreg;
 409        struct squashfs_dir_inode               dir;
 410        struct squashfs_ldir_inode              ldir;
 411        struct squashfs_ipc_inode               ipc;
 412        struct squashfs_lipc_inode              lipc;
 413};
 414
 415struct squashfs_dir_entry {
 416        __le16                  offset;
 417        __le16                  inode_number;
 418        __le16                  type;
 419        __le16                  size;
 420        char                    name[0];
 421};
 422
 423struct squashfs_dir_header {
 424        __le32                  count;
 425        __le32                  start_block;
 426        __le32                  inode_number;
 427};
 428
 429struct squashfs_fragment_entry {
 430        __le64                  start_block;
 431        __le32                  size;
 432        unsigned int            unused;
 433};
 434
 435struct squashfs_xattr_entry {
 436        __le16                  type;
 437        __le16                  size;
 438        char                    data[0];
 439};
 440
 441struct squashfs_xattr_val {
 442        __le32                  vsize;
 443        char                    value[0];
 444};
 445
 446struct squashfs_xattr_id {
 447        __le64                  xattr;
 448        __le32                  count;
 449        __le32                  size;
 450};
 451
 452struct squashfs_xattr_id_table {
 453        __le64                  xattr_table_start;
 454        __le32                  xattr_ids;
 455        __le32                  unused;
 456};
 457
 458#endif
 459