fs/ubifs/ubifs-media.h

   1 /*
   2  * This file is part of UBIFS.
   3  *
   4  * Copyright (C) 2006-2008 Nokia Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 as published by
   8  * the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along with
  16  * this program; if not, write to the Free Software Foundation, Inc., 51
  17  * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  18  *
  19  * Authors: Artem Bityutskiy (Битюцкий Артём)
  20  *          Adrian Hunter
  21  */
  22
  23 /*
  24  * This file describes UBIFS on-flash format and contains definitions of all the
  25  * relevant data structures and constants.
  26  *
  27  * All UBIFS on-flash objects are stored in the form of nodes. All nodes start
  28  * with the UBIFS node magic number and have the same common header. Nodes
  29  * always sit at 8-byte aligned positions on the media and node header sizes are
  30  * also 8-byte aligned (except for the indexing node and the padding node).
  31  */
  32
  33 #ifndef __UBIFS_MEDIA_H__
  34 #define __UBIFS_MEDIA_H__
  35
  36 /* UBIFS node magic number (must not have the padding byte first or last) */
  37 #define UBIFS_NODE_MAGIC  0x06101831
  38
  39 /* UBIFS on-flash format version */
  40 #define UBIFS_FORMAT_VERSION 4
  41
  42 /* Minimum logical eraseblock size in bytes */
  43 #define UBIFS_MIN_LEB_SZ (15*1024)
  44
  45 /* Initial CRC32 value used when calculating CRC checksums */
  46 #define UBIFS_CRC32_INIT 0xFFFFFFFFU
  47
  48 /*
  49  * UBIFS does not try to compress data if its length is less than the below
  50  * constant.
  51  */
  52 #define UBIFS_MIN_COMPR_LEN 128
  53
  54 /*
  55  * If compressed data length is less than %UBIFS_MIN_COMPRESS_DIFF bytes
  56  * shorter than uncompressed data length, UBIFS preferes to leave this data
  57  * node uncompress, because it'll be read faster.
  58  */
  59 #define UBIFS_MIN_COMPRESS_DIFF 64
  60
  61 /* Root inode number */
  62 #define UBIFS_ROOT_INO 1
  63
  64 /* Lowest inode number used for regular inodes (not UBIFS-only internal ones) */
  65 #define UBIFS_FIRST_INO 64
  66
  67 /*
  68  * Maximum file name and extended attribute length (must be a multiple of 8,
  69  * minus 1).
  70  */
  71 #define UBIFS_MAX_NLEN 255
  72
  73 /* Maximum number of data journal heads */
  74 #define UBIFS_MAX_JHEADS 1
  75
  76 /*
  77  * Size of UBIFS data block. Note, UBIFS is not a block oriented file-system,
  78  * which means that it does not treat the underlying media as consisting of
  79  * blocks like in case of hard drives. Do not be confused. UBIFS block is just
  80  * the maximum amount of data which one data node can have or which can be
  81  * attached to an inode node.
  82  */
  83 #define UBIFS_BLOCK_SIZE  4096
  84 #define UBIFS_BLOCK_SHIFT 12
  85
  86 /* UBIFS padding byte pattern (must not be first or last byte of node magic) */
  87 #define UBIFS_PADDING_BYTE 0xCE
  88
  89 /* Maximum possible key length */
  90 #define UBIFS_MAX_KEY_LEN 16
  91
  92 /* Key length ("simple" format) */
  93 #define UBIFS_SK_LEN 8
  94
  95 /* Minimum index tree fanout */
  96 #define UBIFS_MIN_FANOUT 3
  97
  98 /* Maximum number of levels in UBIFS indexing B-tree */
  99 #define UBIFS_MAX_LEVELS 512
 100
 101 /* Maximum amount of data attached to an inode in bytes */
 102 #define UBIFS_MAX_INO_DATA UBIFS_BLOCK_SIZE
 103
 104 /* LEB Properties Tree fanout (must be power of 2) and fanout shift */
 105 #define UBIFS_LPT_FANOUT 4
 106 #define UBIFS_LPT_FANOUT_SHIFT 2
 107
 108 /* LEB Properties Tree bit field sizes */
 109 #define UBIFS_LPT_CRC_BITS 16
 110 #define UBIFS_LPT_CRC_BYTES 2
 111 #define UBIFS_LPT_TYPE_BITS 4
 112
 113 /* The key is always at the same position in all keyed nodes */
 114 #define UBIFS_KEY_OFFSET offsetof(struct ubifs_ino_node, key)
 115
 116 /*
 117  * LEB Properties Tree node types.
 118  *
 119  * UBIFS_LPT_PNODE: LPT leaf node (contains LEB properties)
 120  * UBIFS_LPT_NNODE: LPT internal node
 121  * UBIFS_LPT_LTAB: LPT's own lprops table
 122  * UBIFS_LPT_LSAVE: LPT's save table (big model only)
 123  * UBIFS_LPT_NODE_CNT: count of LPT node types
 124  * UBIFS_LPT_NOT_A_NODE: all ones (15 for 4 bits) is never a valid node type
 125  */
 126 enum {
 127         UBIFS_LPT_PNODE,
 128         UBIFS_LPT_NNODE,
 129         UBIFS_LPT_LTAB,
 130         UBIFS_LPT_LSAVE,
 131         UBIFS_LPT_NODE_CNT,
 132         UBIFS_LPT_NOT_A_NODE = (1 << UBIFS_LPT_TYPE_BITS) - 1,
 133 };
 134
 135 /*
 136  * UBIFS inode types.
 137  *
 138  * UBIFS_ITYPE_REG: regular file
 139  * UBIFS_ITYPE_DIR: directory
 140  * UBIFS_ITYPE_LNK: soft link
 141  * UBIFS_ITYPE_BLK: block device node
 142  * UBIFS_ITYPE_CHR: character device node
 143  * UBIFS_ITYPE_FIFO: fifo
 144  * UBIFS_ITYPE_SOCK: socket
 145  * UBIFS_ITYPES_CNT: count of supported file types
 146  */
 147 enum {
 148         UBIFS_ITYPE_REG,
 149         UBIFS_ITYPE_DIR,
 150         UBIFS_ITYPE_LNK,
 151         UBIFS_ITYPE_BLK,
 152         UBIFS_ITYPE_CHR,
 153         UBIFS_ITYPE_FIFO,
 154         UBIFS_ITYPE_SOCK,
 155         UBIFS_ITYPES_CNT,
 156 };
 157
 158 /*
 159  * Supported key hash functions.
 160  *
 161  * UBIFS_KEY_HASH_R5: R5 hash
 162  * UBIFS_KEY_HASH_TEST: test hash which just returns first 4 bytes of the name
 163  */
 164 enum {
 165         UBIFS_KEY_HASH_R5,
 166         UBIFS_KEY_HASH_TEST,
 167 };
 168
 169 /*
 170  * Supported key formats.
 171  *
 172  * UBIFS_SIMPLE_KEY_FMT: simple key format
 173  */
 174 enum {
 175         UBIFS_SIMPLE_KEY_FMT,
 176 };
 177
 178 /*
 179  * The simple key format uses 29 bits for storing UBIFS block number and hash
 180  * value.
 181  */
 182 #define UBIFS_S_KEY_BLOCK_BITS 29
 183 #define UBIFS_S_KEY_BLOCK_MASK 0x1FFFFFFF
 184 #define UBIFS_S_KEY_HASH_BITS  UBIFS_S_KEY_BLOCK_BITS
 185 #define UBIFS_S_KEY_HASH_MASK  UBIFS_S_KEY_BLOCK_MASK
 186
 187 /*
 188  * Key types.
 189  *
 190  * UBIFS_INO_KEY: inode node key
 191  * UBIFS_DATA_KEY: data node key
 192  * UBIFS_DENT_KEY: directory entry node key
 193  * UBIFS_XENT_KEY: extended attribute entry key
 194  * UBIFS_KEY_TYPES_CNT: number of supported key types
 195  */
 196 enum {
 197         UBIFS_INO_KEY,
 198         UBIFS_DATA_KEY,
 199         UBIFS_DENT_KEY,
 200         UBIFS_XENT_KEY,
 201         UBIFS_KEY_TYPES_CNT,
 202 };
 203
 204 /* Count of LEBs reserved for the superblock area */
 205 #define UBIFS_SB_LEBS 1
 206 /* Count of LEBs reserved for the master area */
 207 #define UBIFS_MST_LEBS 2
 208
 209 /* First LEB of the superblock area */
 210 #define UBIFS_SB_LNUM 0
 211 /* First LEB of the master area */
 212 #define UBIFS_MST_LNUM (UBIFS_SB_LNUM + UBIFS_SB_LEBS)
 213 /* First LEB of the log area */
 214 #define UBIFS_LOG_LNUM (UBIFS_MST_LNUM + UBIFS_MST_LEBS)
 215
 216 /*
 217  * The below constants define the absolute minimum values for various UBIFS
 218  * media areas. Many of them actually depend of flash geometry and the FS
 219  * configuration (number of journal heads, orphan LEBs, etc). This means that
 220  * the smallest volume size which can be used for UBIFS cannot be pre-defined
 221  * by these constants. The file-system that meets the below limitation will not
 222  * necessarily mount. UBIFS does run-time calculations and validates the FS
 223  * size.
 224  */
 225
 226 /* Minimum number of logical eraseblocks in the log */
 227 #define UBIFS_MIN_LOG_LEBS 2
 228 /* Minimum number of bud logical eraseblocks (one for each head) */
 229 #define UBIFS_MIN_BUD_LEBS 3
 230 /* Minimum number of journal logical eraseblocks */
 231 #define UBIFS_MIN_JNL_LEBS (UBIFS_MIN_LOG_LEBS + UBIFS_MIN_BUD_LEBS)
 232 /* Minimum number of LPT area logical eraseblocks */
 233 #define UBIFS_MIN_LPT_LEBS 2
 234 /* Minimum number of orphan area logical eraseblocks */
 235 #define UBIFS_MIN_ORPH_LEBS 1
 236 /*
 237  * Minimum number of main area logical eraseblocks (buds, 3 for the index, 1
 238  * for GC, 1 for deletions, and at least 1 for committed data).
 239  */
 240 #define UBIFS_MIN_MAIN_LEBS (UBIFS_MIN_BUD_LEBS + 6)
 241
 242 /* Minimum number of logical eraseblocks */
 243 #define UBIFS_MIN_LEB_CNT (UBIFS_SB_LEBS + UBIFS_MST_LEBS + \
 244                            UBIFS_MIN_LOG_LEBS + UBIFS_MIN_LPT_LEBS + \
 245                            UBIFS_MIN_ORPH_LEBS + UBIFS_MIN_MAIN_LEBS)
 246
 247 /* Node sizes (N.B. these are guaranteed to be multiples of 8) */
 248 #define UBIFS_CH_SZ        sizeof(struct ubifs_ch)
 249 #define UBIFS_INO_NODE_SZ  sizeof(struct ubifs_ino_node)
 250 #define UBIFS_DATA_NODE_SZ sizeof(struct ubifs_data_node)
 251 #define UBIFS_DENT_NODE_SZ sizeof(struct ubifs_dent_node)
 252 #define UBIFS_TRUN_NODE_SZ sizeof(struct ubifs_trun_node)
 253 #define UBIFS_PAD_NODE_SZ  sizeof(struct ubifs_pad_node)
 254 #define UBIFS_SB_NODE_SZ   sizeof(struct ubifs_sb_node)
 255 #define UBIFS_MST_NODE_SZ  sizeof(struct ubifs_mst_node)
 256 #define UBIFS_REF_NODE_SZ  sizeof(struct ubifs_ref_node)
 257 #define UBIFS_IDX_NODE_SZ  sizeof(struct ubifs_idx_node)
 258 #define UBIFS_CS_NODE_SZ   sizeof(struct ubifs_cs_node)
 259 #define UBIFS_ORPH_NODE_SZ sizeof(struct ubifs_orph_node)
 260 /* Extended attribute entry nodes are identical to directory entry nodes */
 261 #define UBIFS_XENT_NODE_SZ UBIFS_DENT_NODE_SZ
 262 /* Only this does not have to be multiple of 8 bytes */
 263 #define UBIFS_BRANCH_SZ    sizeof(struct ubifs_branch)
 264
 265 /* Maximum node sizes (N.B. these are guaranteed to be multiples of 8) */
 266 #define UBIFS_MAX_DATA_NODE_SZ  (UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE)
 267 #define UBIFS_MAX_INO_NODE_SZ   (UBIFS_INO_NODE_SZ + UBIFS_MAX_INO_DATA)
 268 #define UBIFS_MAX_DENT_NODE_SZ  (UBIFS_DENT_NODE_SZ + UBIFS_MAX_NLEN + 1)
 269 #define UBIFS_MAX_XENT_NODE_SZ  UBIFS_MAX_DENT_NODE_SZ
 270
 271 /* The largest UBIFS node */
 272 #define UBIFS_MAX_NODE_SZ UBIFS_MAX_INO_NODE_SZ
 273
 274 /*
 275  * On-flash inode flags.
 276  *
 277  * UBIFS_COMPR_FL: use compression for this inode
 278  * UBIFS_SYNC_FL:  I/O on this inode has to be synchronous
 279  * UBIFS_IMMUTABLE_FL: inode is immutable
 280  * UBIFS_APPEND_FL: writes to the inode may only append data
 281  * UBIFS_DIRSYNC_FL: I/O on this directory inode has to be synchronous
 282  * UBIFS_XATTR_FL: this inode is the inode for an extended attribute value
 283  *
 284  * Note, these are on-flash flags which correspond to ioctl flags
 285  * (@FS_COMPR_FL, etc). They have the same values now, but generally, do not
 286  * have to be the same.
 287  */
 288 enum {
 289         UBIFS_COMPR_FL     = 0x01,
 290         UBIFS_SYNC_FL      = 0x02,
 291         UBIFS_IMMUTABLE_FL = 0x04,
 292         UBIFS_APPEND_FL    = 0x08,
 293         UBIFS_DIRSYNC_FL   = 0x10,
 294         UBIFS_XATTR_FL     = 0x20,
 295 };
 296
 297 /* Inode flag bits used by UBIFS */
 298 #define UBIFS_FL_MASK 0x0000001F
 299
 300 /*
 301  * UBIFS compression algorithms.
 302  *
 303  * UBIFS_COMPR_NONE: no compression
 304  * UBIFS_COMPR_LZO: LZO compression
 305  * UBIFS_COMPR_ZLIB: ZLIB compression
 306  * UBIFS_COMPR_TYPES_CNT: count of supported compression types
 307  */
 308 enum {
 309         UBIFS_COMPR_NONE,
 310         UBIFS_COMPR_LZO,
 311         UBIFS_COMPR_ZLIB,
 312         UBIFS_COMPR_TYPES_CNT,
 313 };
 314
 315 /*
 316  * UBIFS node types.
 317  *
 318  * UBIFS_INO_NODE: inode node
 319  * UBIFS_DATA_NODE: data node
 320  * UBIFS_DENT_NODE: directory entry node
 321  * UBIFS_XENT_NODE: extended attribute node
 322  * UBIFS_TRUN_NODE: truncation node
 323  * UBIFS_PAD_NODE: padding node
 324  * UBIFS_SB_NODE: superblock node
 325  * UBIFS_MST_NODE: master node
 326  * UBIFS_REF_NODE: LEB reference node
 327  * UBIFS_IDX_NODE: index node
 328  * UBIFS_CS_NODE: commit start node
 329  * UBIFS_ORPH_NODE: orphan node
 330  * UBIFS_NODE_TYPES_CNT: count of supported node types
 331  *
 332  * Note, we index arrays by these numbers, so keep them low and contiguous.
 333  * Node type constants for inodes, direntries and so on have to be the same as
 334  * corresponding key type constants.
 335  */
 336 enum {
 337         UBIFS_INO_NODE,
 338         UBIFS_DATA_NODE,
 339         UBIFS_DENT_NODE,
 340         UBIFS_XENT_NODE,
 341         UBIFS_TRUN_NODE,
 342         UBIFS_PAD_NODE,
 343         UBIFS_SB_NODE,
 344         UBIFS_MST_NODE,
 345         UBIFS_REF_NODE,
 346         UBIFS_IDX_NODE,
 347         UBIFS_CS_NODE,
 348         UBIFS_ORPH_NODE,
 349         UBIFS_NODE_TYPES_CNT,
 350 };
 351
 352 /*
 353  * Master node flags.
 354  *
 355  * UBIFS_MST_DIRTY: rebooted uncleanly - master node is dirty
 356  * UBIFS_MST_NO_ORPHS: no orphan inodes present
 357  * UBIFS_MST_RCVRY: written by recovery
 358  */
 359 enum {
 360         UBIFS_MST_DIRTY = 1,
 361         UBIFS_MST_NO_ORPHS = 2,
 362         UBIFS_MST_RCVRY = 4,
 363 };
 364
 365 /*
 366  * Node group type (used by recovery to recover whole group or none).
 367  *
 368  * UBIFS_NO_NODE_GROUP: this node is not part of a group
 369  * UBIFS_IN_NODE_GROUP: this node is a part of a group
 370  * UBIFS_LAST_OF_NODE_GROUP: this node is the last in a group
 371  */
 372 enum {
 373         UBIFS_NO_NODE_GROUP = 0,
 374         UBIFS_IN_NODE_GROUP,
 375         UBIFS_LAST_OF_NODE_GROUP,
 376 };
 377
 378 /*
 379  * Superblock flags.
 380  *
 381  * UBIFS_FLG_BIGLPT: if "big" LPT model is used if set
 382  */
 383 enum {
 384         UBIFS_FLG_BIGLPT = 0x02,
 385 };
 386
 387 /**
 388  * struct ubifs_ch - common header node.
 389  * @magic: UBIFS node magic number (%UBIFS_NODE_MAGIC)
 390  * @crc: CRC-32 checksum of the node header
 391  * @sqnum: sequence number
 392  * @len: full node length
 393  * @node_type: node type
 394  * @group_type: node group type
 395  * @padding: reserved for future, zeroes
 396  *
 397  * Every UBIFS node starts with this common part. If the node has a key, the
 398  * key always goes next.
 399  */
 400 struct ubifs_ch {
 401         __le32 magic;
 402         __le32 crc;
 403         __le64 sqnum;
 404         __le32 len;
 405         __u8 node_type;
 406         __u8 group_type;
 407         __u8 padding[2];
 408 } __attribute__ ((packed));
 409
 410 /**
 411  * union ubifs_dev_desc - device node descriptor.
 412  * @new: new type device descriptor
 413  * @huge: huge type device descriptor
 414  *
 415  * This data structure describes major/minor numbers of a device node. In an
 416  * inode is a device node then its data contains an object of this type. UBIFS
 417  * uses standard Linux "new" and "huge" device node encodings.
 418  */
 419 union ubifs_dev_desc {
 420         __le32 new;
 421         __le64 huge;
 422 } __attribute__ ((packed));
 423
 424 /**
 425  * struct ubifs_ino_node - inode node.
 426  * @ch: common header
 427  * @key: node key
 428  * @creat_sqnum: sequence number at time of creation
 429  * @size: inode size in bytes (amount of uncompressed data)
 430  * @atime_sec: access time seconds
 431  * @ctime_sec: creation time seconds
 432  * @mtime_sec: modification time seconds
 433  * @atime_nsec: access time nanoseconds
 434  * @ctime_nsec: creation time nanoseconds
 435  * @mtime_nsec: modification time nanoseconds
 436  * @nlink: number of hard links
 437  * @uid: owner ID
 438  * @gid: group ID
 439  * @mode: access flags
 440  * @flags: per-inode flags (%UBIFS_COMPR_FL, %UBIFS_SYNC_FL, etc)
 441  * @data_len: inode data length
 442  * @xattr_cnt: count of extended attributes this inode has
 443  * @xattr_size: summarized size of all extended attributes in bytes
 444  * @padding1: reserved for future, zeroes
 445  * @xattr_names: sum of lengths of all extended attribute names belonging to
 446  *               this inode
 447  * @compr_type: compression type used for this inode
 448  * @padding2: reserved for future, zeroes
 449  * @data: data attached to the inode
 450  *
 451  * Note, even though inode compression type is defined by @compr_type, some
 452  * nodes of this inode may be compressed with different compressor - this
 453  * happens if compression type is changed while the inode already has data
 454  * nodes. But @compr_type will be use for further writes to the inode.
 455  *
 456  * Note, do not forget to amend 'zero_ino_node_unused()' function when changing
 457  * the padding fields.
 458  */
 459 struct ubifs_ino_node {
 460         struct ubifs_ch ch;
 461         __u8 key[UBIFS_MAX_KEY_LEN];
 462         __le64 creat_sqnum;
 463         __le64 size;
 464         __le64 atime_sec;
 465         __le64 ctime_sec;
 466         __le64 mtime_sec;
 467         __le32 atime_nsec;
 468         __le32 ctime_nsec;
 469         __le32 mtime_nsec;
 470         __le32 nlink;
 471         __le32 uid;
 472         __le32 gid;
 473         __le32 mode;
 474         __le32 flags;
 475         __le32 data_len;
 476         __le32 xattr_cnt;
 477         __le32 xattr_size;
 478         __u8 padding1[4]; /* Watch 'zero_ino_node_unused()' if changing! */
 479         __le32 xattr_names;
 480         __le16 compr_type;
 481         __u8 padding2[26]; /* Watch 'zero_ino_node_unused()' if changing! */
 482         __u8 data[];
 483 } __attribute__ ((packed));
 484
 485 /**
 486  * struct ubifs_dent_node - directory entry node.
 487  * @ch: common header
 488  * @key: node key
 489  * @inum: target inode number
 490  * @padding1: reserved for future, zeroes
 491  * @type: type of the target inode (%UBIFS_ITYPE_REG, %UBIFS_ITYPE_DIR, etc)
 492  * @nlen: name length
 493  * @padding2: reserved for future, zeroes
 494  * @name: zero-terminated name
 495  *
 496  * Note, do not forget to amend 'zero_dent_node_unused()' function when
 497  * changing the padding fields.
 498  */
 499 struct ubifs_dent_node {
 500         struct ubifs_ch ch;
 501         __u8 key[UBIFS_MAX_KEY_LEN];
 502         __le64 inum;
 503         __u8 padding1;
 504         __u8 type;
 505         __le16 nlen;
 506         __u8 padding2[4]; /* Watch 'zero_dent_node_unused()' if changing! */
 507         __u8 name[];
 508 } __attribute__ ((packed));
 509
 510 /**
 511  * struct ubifs_data_node - data node.
 512  * @ch: common header
 513  * @key: node key
 514  * @size: uncompressed data size in bytes
 515  * @compr_type: compression type (%UBIFS_COMPR_NONE, %UBIFS_COMPR_LZO, etc)
 516  * @padding: reserved for future, zeroes
 517  * @data: data
 518  *
 519  * Note, do not forget to amend 'zero_data_node_unused()' function when
 520  * changing the padding fields.
 521  */
 522 struct ubifs_data_node {
 523         struct ubifs_ch ch;
 524         __u8 key[UBIFS_MAX_KEY_LEN];
 525         __le32 size;
 526         __le16 compr_type;
 527         __u8 padding[2]; /* Watch 'zero_data_node_unused()' if changing! */
 528         __u8 data[];
 529 } __attribute__ ((packed));
 530
 531 /**
 532  * struct ubifs_trun_node - truncation node.
 533  * @ch: common header
 534  * @inum: truncated inode number
 535  * @padding: reserved for future, zeroes
 536  * @old_size: size before truncation
 537  * @new_size: size after truncation
 538  *
 539  * This node exists only in the journal and never goes to the main area. Note,
 540  * do not forget to amend 'zero_trun_node_unused()' function when changing the
 541  * padding fields.
 542  */
 543 struct ubifs_trun_node {
 544         struct ubifs_ch ch;
 545         __le32 inum;
 546         __u8 padding[12]; /* Watch 'zero_trun_node_unused()' if changing! */
 547         __le64 old_size;
 548         __le64 new_size;
 549 } __attribute__ ((packed));
 550
 551 /**
 552  * struct ubifs_pad_node - padding node.
 553  * @ch: common header
 554  * @pad_len: how many bytes after this node are unused (because padded)
 555  * @padding: reserved for future, zeroes
 556  */
 557 struct ubifs_pad_node {
 558         struct ubifs_ch ch;
 559         __le32 pad_len;
 560 } __attribute__ ((packed));
 561
 562 /**
 563  * struct ubifs_sb_node - superblock node.
 564  * @ch: common header
 565  * @padding: reserved for future, zeroes
 566  * @key_hash: type of hash function used in keys
 567  * @key_fmt: format of the key
 568  * @flags: file-system flags (%UBIFS_FLG_BIGLPT, etc)
 569  * @min_io_size: minimal input/output unit size
 570  * @leb_size: logical eraseblock size in bytes
 571  * @leb_cnt: count of LEBs used by file-system
 572  * @max_leb_cnt: maximum count of LEBs used by file-system
 573  * @max_bud_bytes: maximum amount of data stored in buds
 574  * @log_lebs: log size in logical eraseblocks
 575  * @lpt_lebs: number of LEBs used for lprops table
 576  * @orph_lebs: number of LEBs used for recording orphans
 577  * @jhead_cnt: count of journal heads
 578  * @fanout: tree fanout (max. number of links per indexing node)
 579  * @lsave_cnt: number of LEB numbers in LPT's save table
 580  * @fmt_version: UBIFS on-flash format version
 581  * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc)
 582  * @padding1: reserved for future, zeroes
 583  * @rp_uid: reserve pool UID
 584  * @rp_gid: reserve pool GID
 585  * @rp_size: size of the reserved pool in bytes
 586  * @padding2: reserved for future, zeroes
 587  * @time_gran: time granularity in nanoseconds
 588  * @uuid: UUID generated when the file system image was created
 589  */
 590 struct ubifs_sb_node {
 591         struct ubifs_ch ch;
 592         __u8 padding[2];
 593         __u8 key_hash;
 594         __u8 key_fmt;
 595         __le32 flags;
 596         __le32 min_io_size;
 597         __le32 leb_size;
 598         __le32 leb_cnt;
 599         __le32 max_leb_cnt;
 600         __le64 max_bud_bytes;
 601         __le32 log_lebs;
 602         __le32 lpt_lebs;
 603         __le32 orph_lebs;
 604         __le32 jhead_cnt;
 605         __le32 fanout;
 606         __le32 lsave_cnt;
 607         __le32 fmt_version;
 608         __le16 default_compr;
 609         __u8 padding1[2];
 610         __le32 rp_uid;
 611         __le32 rp_gid;
 612         __le64 rp_size;
 613         __le32 time_gran;
 614         __u8 uuid[16];
 615         __u8 padding2[3972];
 616 } __attribute__ ((packed));
 617
 618 /**
 619  * struct ubifs_mst_node - master node.
 620  * @ch: common header
 621  * @highest_inum: highest inode number in the committed index
 622  * @cmt_no: commit number
 623  * @flags: various flags (%UBIFS_MST_DIRTY, etc)
 624  * @log_lnum: start of the log
 625  * @root_lnum: LEB number of the root indexing node
 626  * @root_offs: offset within @root_lnum
 627  * @root_len: root indexing node length
 628  * @gc_lnum: LEB reserved for garbage collection (%-1 value means the LEB was
 629  * not reserved and should be reserved on mount)
 630  * @ihead_lnum: LEB number of index head
 631  * @ihead_offs: offset of index head
 632  * @index_size: size of index on flash
 633  * @total_free: total free space in bytes
 634  * @total_dirty: total dirty space in bytes
 635  * @total_used: total used space in bytes (includes only data LEBs)
 636  * @total_dead: total dead space in bytes (includes only data LEBs)
 637  * @total_dark: total dark space in bytes (includes only data LEBs)
 638  * @lpt_lnum: LEB number of LPT root nnode
 639  * @lpt_offs: offset of LPT root nnode
 640  * @nhead_lnum: LEB number of LPT head
 641  * @nhead_offs: offset of LPT head
 642  * @ltab_lnum: LEB number of LPT's own lprops table
 643  * @ltab_offs: offset of LPT's own lprops table
 644  * @lsave_lnum: LEB number of LPT's save table (big model only)
 645  * @lsave_offs: offset of LPT's save table (big model only)
 646  * @lscan_lnum: LEB number of last LPT scan
 647  * @empty_lebs: number of empty logical eraseblocks
 648  * @idx_lebs: number of indexing logical eraseblocks
 649  * @leb_cnt: count of LEBs used by file-system
 650  * @padding: reserved for future, zeroes
 651  */
 652 struct ubifs_mst_node {
 653         struct ubifs_ch ch;
 654         __le64 highest_inum;
 655         __le64 cmt_no;
 656         __le32 flags;
 657         __le32 log_lnum;
 658         __le32 root_lnum;
 659         __le32 root_offs;
 660         __le32 root_len;
 661         __le32 gc_lnum;
 662         __le32 ihead_lnum;
 663         __le32 ihead_offs;
 664         __le64 index_size;
 665         __le64 total_free;
 666         __le64 total_dirty;
 667         __le64 total_used;
 668         __le64 total_dead;
 669         __le64 total_dark;
 670         __le32 lpt_lnum;
 671         __le32 lpt_offs;
 672         __le32 nhead_lnum;
 673         __le32 nhead_offs;
 674         __le32 ltab_lnum;
 675         __le32 ltab_offs;
 676         __le32 lsave_lnum;
 677         __le32 lsave_offs;
 678         __le32 lscan_lnum;
 679         __le32 empty_lebs;
 680         __le32 idx_lebs;
 681         __le32 leb_cnt;
 682         __u8 padding[344];
 683 } __attribute__ ((packed));
 684
 685 /**
 686  * struct ubifs_ref_node - logical eraseblock reference node.
 687  * @ch: common header
 688  * @lnum: the referred logical eraseblock number
 689  * @offs: start offset in the referred LEB
 690  * @jhead: journal head number
 691  * @padding: reserved for future, zeroes
 692  */
 693 struct ubifs_ref_node {
 694         struct ubifs_ch ch;
 695         __le32 lnum;
 696         __le32 offs;
 697         __le32 jhead;
 698         __u8 padding[28];
 699 } __attribute__ ((packed));
 700
 701 /**
 702  * struct ubifs_branch - key/reference/length branch
 703  * @lnum: LEB number of the target node
 704  * @offs: offset within @lnum
 705  * @len: target node length
 706  * @key: key
 707  */
 708 struct ubifs_branch {
 709         __le32 lnum;
 710         __le32 offs;
 711         __le32 len;
 712         __u8 key[];
 713 } __attribute__ ((packed));
 714
 715 /**
 716  * struct ubifs_idx_node - indexing node.
 717  * @ch: common header
 718  * @child_cnt: number of child index nodes
 719  * @level: tree level
 720  * @branches: LEB number / offset / length / key branches
 721  */
 722 struct ubifs_idx_node {
 723         struct ubifs_ch ch;
 724         __le16 child_cnt;
 725         __le16 level;
 726         __u8 branches[];
 727 } __attribute__ ((packed));
 728
 729 /**
 730  * struct ubifs_cs_node - commit start node.
 731  * @ch: common header
 732  * @cmt_no: commit number
 733  */
 734 struct ubifs_cs_node {
 735         struct ubifs_ch ch;
 736         __le64 cmt_no;
 737 } __attribute__ ((packed));
 738
 739 /**
 740  * struct ubifs_orph_node - orphan node.
 741  * @ch: common header
 742  * @cmt_no: commit number (also top bit is set on the last node of the commit)
 743  * @inos: inode numbers of orphans
 744  */
 745 struct ubifs_orph_node {
 746         struct ubifs_ch ch;
 747         __le64 cmt_no;
 748         __le64 inos[];
 749 } __attribute__ ((packed));
 750
 751 #endif /* __UBIFS_MEDIA_H__ */