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 /* 40 * UBIFS on-flash format version. This version is increased when the on-flash 41 * format is changing. If this happens, UBIFS is will support older versions as 42 * well. But older UBIFS code will not support newer formats. Format changes 43 * will be rare and only when absolutely necessary, e.g. to fix a bug or to add 44 * a new feature. 45 * 46 * UBIFS went into mainline kernel with format version 4. The older formats 47 * were development formats. 48 */ 49 #define UBIFS_FORMAT_VERSION 5 50 51 /* 52 * Read-only compatibility version. If the UBIFS format is changed, older UBIFS 53 * implementations will not be able to mount newer formats in read-write mode. 54 * However, depending on the change, it may be possible to mount newer formats 55 * in R/O mode. This is indicated by the R/O compatibility version which is 56 * stored in the super-block. 57 * 58 * This is needed to support boot-loaders which only need R/O mounting. With 59 * this flag it is possible to do UBIFS format changes without a need to update 60 * boot-loaders. 61 */ 62 #define UBIFS_RO_COMPAT_VERSION 0 63 64 /* Minimum logical eraseblock size in bytes */ 65 #define UBIFS_MIN_LEB_SZ (15*1024) 66 67 /* Initial CRC32 value used when calculating CRC checksums */ 68 #define UBIFS_CRC32_INIT 0xFFFFFFFFU 69 70 /* 71 * UBIFS does not try to compress data if its length is less than the below 72 * constant. 73 */ 74 #define UBIFS_MIN_COMPR_LEN 128 75 76 /* 77 * If compressed data length is less than %UBIFS_MIN_COMPRESS_DIFF bytes 78 * shorter than uncompressed data length, UBIFS prefers to leave this data 79 * node uncompress, because it'll be read faster. 80 */ 81 #define UBIFS_MIN_COMPRESS_DIFF 64 82 83 /* Root inode number */ 84 #define UBIFS_ROOT_INO 1 85 86 /* Lowest inode number used for regular inodes (not UBIFS-only internal ones) */ 87 #define UBIFS_FIRST_INO 64 88 89 /* 90 * Maximum file name and extended attribute length (must be a multiple of 8, 91 * minus 1). 92 */ 93 #define UBIFS_MAX_NLEN 255 94 95 /* Maximum number of data journal heads */ 96 #define UBIFS_MAX_JHEADS 1 97 98 /* 99 * Size of UBIFS data block. Note, UBIFS is not a block oriented file-system, 100 * which means that it does not treat the underlying media as consisting of 101 * blocks like in case of hard drives. Do not be confused. UBIFS block is just 102 * the maximum amount of data which one data node can have or which can be 103 * attached to an inode node. 104 */ 105 #define UBIFS_BLOCK_SIZE 4096 106 #define UBIFS_BLOCK_SHIFT 12 107 108 /* UBIFS padding byte pattern (must not be first or last byte of node magic) */ 109 #define UBIFS_PADDING_BYTE 0xCE 110 111 /* Maximum possible key length */ 112 #define UBIFS_MAX_KEY_LEN 16 113 114 /* Key length ("simple" format) */ 115 #define UBIFS_SK_LEN 8 116 117 /* Minimum index tree fanout */ 118 #define UBIFS_MIN_FANOUT 3 119 120 /* Maximum number of levels in UBIFS indexing B-tree */ 121 #define UBIFS_MAX_LEVELS 512 122 123 /* Maximum amount of data attached to an inode in bytes */ 124 #define UBIFS_MAX_INO_DATA UBIFS_BLOCK_SIZE 125 126 /* LEB Properties Tree fanout (must be power of 2) and fanout shift */ 127 #define UBIFS_LPT_FANOUT 4 128 #define UBIFS_LPT_FANOUT_SHIFT 2 129 130 /* LEB Properties Tree bit field sizes */ 131 #define UBIFS_LPT_CRC_BITS 16 132 #define UBIFS_LPT_CRC_BYTES 2 133 #define UBIFS_LPT_TYPE_BITS 4 134 135 /* The key is always at the same position in all keyed nodes */ 136 #define UBIFS_KEY_OFFSET offsetof(struct ubifs_ino_node, key) 137 138 /* Garbage collector journal head number */ 139 #define UBIFS_GC_HEAD 0 140 /* Base journal head number */ 141 #define UBIFS_BASE_HEAD 1 142 /* Data journal head number */ 143 #define UBIFS_DATA_HEAD 2 144 145 /* 146 * LEB Properties Tree node types. 147 * 148 * UBIFS_LPT_PNODE: LPT leaf node (contains LEB properties) 149 * UBIFS_LPT_NNODE: LPT internal node 150 * UBIFS_LPT_LTAB: LPT's own lprops table 151 * UBIFS_LPT_LSAVE: LPT's save table (big model only) 152 * UBIFS_LPT_NODE_CNT: count of LPT node types 153 * UBIFS_LPT_NOT_A_NODE: all ones (15 for 4 bits) is never a valid node type 154 */ 155 enum { 156 UBIFS_LPT_PNODE, 157 UBIFS_LPT_NNODE, 158 UBIFS_LPT_LTAB, 159 UBIFS_LPT_LSAVE, 160 UBIFS_LPT_NODE_CNT, 161 UBIFS_LPT_NOT_A_NODE = (1 << UBIFS_LPT_TYPE_BITS) - 1, 162 }; 163 164 /* 165 * UBIFS inode types. 166 * 167 * UBIFS_ITYPE_REG: regular file 168 * UBIFS_ITYPE_DIR: directory 169 * UBIFS_ITYPE_LNK: soft link 170 * UBIFS_ITYPE_BLK: block device node 171 * UBIFS_ITYPE_CHR: character device node 172 * UBIFS_ITYPE_FIFO: fifo 173 * UBIFS_ITYPE_SOCK: socket 174 * UBIFS_ITYPES_CNT: count of supported file types 175 */ 176 enum { 177 UBIFS_ITYPE_REG, 178 UBIFS_ITYPE_DIR, 179 UBIFS_ITYPE_LNK, 180 UBIFS_ITYPE_BLK, 181 UBIFS_ITYPE_CHR, 182 UBIFS_ITYPE_FIFO, 183 UBIFS_ITYPE_SOCK, 184 UBIFS_ITYPES_CNT, 185 }; 186 187 /* 188 * Supported key hash functions. 189 * 190 * UBIFS_KEY_HASH_R5: R5 hash 191 * UBIFS_KEY_HASH_TEST: test hash which just returns first 4 bytes of the name 192 */ 193 enum { 194 UBIFS_KEY_HASH_R5, 195 UBIFS_KEY_HASH_TEST, 196 }; 197 198 /* 199 * Supported key formats. 200 * 201 * UBIFS_SIMPLE_KEY_FMT: simple key format 202 */ 203 enum { 204 UBIFS_SIMPLE_KEY_FMT, 205 }; 206 207 /* 208 * The simple key format uses 29 bits for storing UBIFS block number and hash 209 * value. 210 */ 211 #define UBIFS_S_KEY_BLOCK_BITS 29 212 #define UBIFS_S_KEY_BLOCK_MASK 0x1FFFFFFF 213 #define UBIFS_S_KEY_HASH_BITS UBIFS_S_KEY_BLOCK_BITS 214 #define UBIFS_S_KEY_HASH_MASK UBIFS_S_KEY_BLOCK_MASK 215 216 /* 217 * Key types. 218 * 219 * UBIFS_INO_KEY: inode node key 220 * UBIFS_DATA_KEY: data node key 221 * UBIFS_DENT_KEY: directory entry node key 222 * UBIFS_XENT_KEY: extended attribute entry key 223 * UBIFS_KEY_TYPES_CNT: number of supported key types 224 */ 225 enum { 226 UBIFS_INO_KEY, 227 UBIFS_DATA_KEY, 228 UBIFS_DENT_KEY, 229 UBIFS_XENT_KEY, 230 UBIFS_KEY_TYPES_CNT, 231 }; 232 233 /* Count of LEBs reserved for the superblock area */ 234 #define UBIFS_SB_LEBS 1 235 /* Count of LEBs reserved for the master area */ 236 #define UBIFS_MST_LEBS 2 237 238 /* First LEB of the superblock area */ 239 #define UBIFS_SB_LNUM 0 240 /* First LEB of the master area */ 241 #define UBIFS_MST_LNUM (UBIFS_SB_LNUM + UBIFS_SB_LEBS) 242 /* First LEB of the log area */ 243 #define UBIFS_LOG_LNUM (UBIFS_MST_LNUM + UBIFS_MST_LEBS) 244 245 /* 246 * The below constants define the absolute minimum values for various UBIFS 247 * media areas. Many of them actually depend of flash geometry and the FS 248 * configuration (number of journal heads, orphan LEBs, etc). This means that 249 * the smallest volume size which can be used for UBIFS cannot be pre-defined 250 * by these constants. The file-system that meets the below limitation will not 251 * necessarily mount. UBIFS does run-time calculations and validates the FS 252 * size. 253 */ 254 255 /* Minimum number of logical eraseblocks in the log */ 256 #define UBIFS_MIN_LOG_LEBS 2 257 /* Minimum number of bud logical eraseblocks (one for each head) */ 258 #define UBIFS_MIN_BUD_LEBS 3 259 /* Minimum number of journal logical eraseblocks */ 260 #define UBIFS_MIN_JNL_LEBS (UBIFS_MIN_LOG_LEBS + UBIFS_MIN_BUD_LEBS) 261 /* Minimum number of LPT area logical eraseblocks */ 262 #define UBIFS_MIN_LPT_LEBS 2 263 /* Minimum number of orphan area logical eraseblocks */ 264 #define UBIFS_MIN_ORPH_LEBS 1 265 /* 266 * Minimum number of main area logical eraseblocks (buds, 3 for the index, 1 267 * for GC, 1 for deletions, and at least 1 for committed data). 268 */ 269 #define UBIFS_MIN_MAIN_LEBS (UBIFS_MIN_BUD_LEBS + 6) 270 271 /* Minimum number of logical eraseblocks */ 272 #define UBIFS_MIN_LEB_CNT (UBIFS_SB_LEBS + UBIFS_MST_LEBS + \ 273 UBIFS_MIN_LOG_LEBS + UBIFS_MIN_LPT_LEBS + \ 274 UBIFS_MIN_ORPH_LEBS + UBIFS_MIN_MAIN_LEBS) 275 276 /* Node sizes (N.B. these are guaranteed to be multiples of 8) */ 277 #define UBIFS_CH_SZ sizeof(struct ubifs_ch) 278 #define UBIFS_INO_NODE_SZ sizeof(struct ubifs_ino_node) 279 #define UBIFS_DATA_NODE_SZ sizeof(struct ubifs_data_node) 280 #define UBIFS_DENT_NODE_SZ sizeof(struct ubifs_dent_node) 281 #define UBIFS_TRUN_NODE_SZ sizeof(struct ubifs_trun_node) 282 #define UBIFS_PAD_NODE_SZ sizeof(struct ubifs_pad_node) 283 #define UBIFS_SB_NODE_SZ sizeof(struct ubifs_sb_node) 284 #define UBIFS_MST_NODE_SZ sizeof(struct ubifs_mst_node) 285 #define UBIFS_REF_NODE_SZ sizeof(struct ubifs_ref_node) 286 #define UBIFS_IDX_NODE_SZ sizeof(struct ubifs_idx_node) 287 #define UBIFS_CS_NODE_SZ sizeof(struct ubifs_cs_node) 288 #define UBIFS_ORPH_NODE_SZ sizeof(struct ubifs_orph_node) 289 /* Extended attribute entry nodes are identical to directory entry nodes */ 290 #define UBIFS_XENT_NODE_SZ UBIFS_DENT_NODE_SZ 291 /* Only this does not have to be multiple of 8 bytes */ 292 #define UBIFS_BRANCH_SZ sizeof(struct ubifs_branch) 293 294 /* Maximum node sizes (N.B. these are guaranteed to be multiples of 8) */ 295 #define UBIFS_MAX_DATA_NODE_SZ (UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE) 296 #define UBIFS_MAX_INO_NODE_SZ (UBIFS_INO_NODE_SZ + UBIFS_MAX_INO_DATA) 297 #define UBIFS_MAX_DENT_NODE_SZ (UBIFS_DENT_NODE_SZ + UBIFS_MAX_NLEN + 1) 298 #define UBIFS_MAX_XENT_NODE_SZ UBIFS_MAX_DENT_NODE_SZ 299 300 /* The largest UBIFS node */ 301 #define UBIFS_MAX_NODE_SZ UBIFS_MAX_INO_NODE_SZ 302 303 /* 304 * xattr name of UBIFS encryption context, we don't use a prefix 305 * nor a long name to not waste space on the flash. 306 */ 307 #define UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT "c" 308 309 310 /* 311 * On-flash inode flags. 312 * 313 * UBIFS_COMPR_FL: use compression for this inode 314 * UBIFS_SYNC_FL: I/O on this inode has to be synchronous 315 * UBIFS_IMMUTABLE_FL: inode is immutable 316 * UBIFS_APPEND_FL: writes to the inode may only append data 317 * UBIFS_DIRSYNC_FL: I/O on this directory inode has to be synchronous 318 * UBIFS_XATTR_FL: this inode is the inode for an extended attribute value 319 * UBIFS_CRYPT_FL: use encryption for this inode 320 * 321 * Note, these are on-flash flags which correspond to ioctl flags 322 * (@FS_COMPR_FL, etc). They have the same values now, but generally, do not 323 * have to be the same. 324 */ 325 enum { 326 UBIFS_COMPR_FL = 0x01, 327 UBIFS_SYNC_FL = 0x02, 328 UBIFS_IMMUTABLE_FL = 0x04, 329 UBIFS_APPEND_FL = 0x08, 330 UBIFS_DIRSYNC_FL = 0x10, 331 UBIFS_XATTR_FL = 0x20, 332 UBIFS_CRYPT_FL = 0x40, 333 }; 334 335 /* Inode flag bits used by UBIFS */ 336 #define UBIFS_FL_MASK 0x0000001F 337 338 /* 339 * UBIFS compression algorithms. 340 * 341 * UBIFS_COMPR_NONE: no compression 342 * UBIFS_COMPR_LZO: LZO compression 343 * UBIFS_COMPR_ZLIB: ZLIB compression 344 * UBIFS_COMPR_TYPES_CNT: count of supported compression types 345 */ 346 enum { 347 UBIFS_COMPR_NONE, 348 UBIFS_COMPR_LZO, 349 UBIFS_COMPR_ZLIB, 350 UBIFS_COMPR_TYPES_CNT, 351 }; 352 353 /* 354 * UBIFS node types. 355 * 356 * UBIFS_INO_NODE: inode node 357 * UBIFS_DATA_NODE: data node 358 * UBIFS_DENT_NODE: directory entry node 359 * UBIFS_XENT_NODE: extended attribute node 360 * UBIFS_TRUN_NODE: truncation node 361 * UBIFS_PAD_NODE: padding node 362 * UBIFS_SB_NODE: superblock node 363 * UBIFS_MST_NODE: master node 364 * UBIFS_REF_NODE: LEB reference node 365 * UBIFS_IDX_NODE: index node 366 * UBIFS_CS_NODE: commit start node 367 * UBIFS_ORPH_NODE: orphan node 368 * UBIFS_NODE_TYPES_CNT: count of supported node types 369 * 370 * Note, we index arrays by these numbers, so keep them low and contiguous. 371 * Node type constants for inodes, direntries and so on have to be the same as 372 * corresponding key type constants. 373 */ 374 enum { 375 UBIFS_INO_NODE, 376 UBIFS_DATA_NODE, 377 UBIFS_DENT_NODE, 378 UBIFS_XENT_NODE, 379 UBIFS_TRUN_NODE, 380 UBIFS_PAD_NODE, 381 UBIFS_SB_NODE, 382 UBIFS_MST_NODE, 383 UBIFS_REF_NODE, 384 UBIFS_IDX_NODE, 385 UBIFS_CS_NODE, 386 UBIFS_ORPH_NODE, 387 UBIFS_NODE_TYPES_CNT, 388 }; 389 390 /* 391 * Master node flags. 392 * 393 * UBIFS_MST_DIRTY: rebooted uncleanly - master node is dirty 394 * UBIFS_MST_NO_ORPHS: no orphan inodes present 395 * UBIFS_MST_RCVRY: written by recovery 396 */ 397 enum { 398 UBIFS_MST_DIRTY = 1, 399 UBIFS_MST_NO_ORPHS = 2, 400 UBIFS_MST_RCVRY = 4, 401 }; 402 403 /* 404 * Node group type (used by recovery to recover whole group or none). 405 * 406 * UBIFS_NO_NODE_GROUP: this node is not part of a group 407 * UBIFS_IN_NODE_GROUP: this node is a part of a group 408 * UBIFS_LAST_OF_NODE_GROUP: this node is the last in a group 409 */ 410 enum { 411 UBIFS_NO_NODE_GROUP = 0, 412 UBIFS_IN_NODE_GROUP, 413 UBIFS_LAST_OF_NODE_GROUP, 414 }; 415 416 /* 417 * Superblock flags. 418 * 419 * UBIFS_FLG_BIGLPT: if "big" LPT model is used if set 420 * UBIFS_FLG_SPACE_FIXUP: first-mount "fixup" of free space within LEBs needed 421 * UBIFS_FLG_DOUBLE_HASH: store a 32bit cookie in directory entry nodes to 422 * support 64bit cookies for lookups by hash 423 * UBIFS_FLG_ENCRYPTION: this filesystem contains encrypted files 424 */ 425 enum { 426 UBIFS_FLG_BIGLPT = 0x02, 427 UBIFS_FLG_SPACE_FIXUP = 0x04, 428 UBIFS_FLG_DOUBLE_HASH = 0x08, 429 UBIFS_FLG_ENCRYPTION = 0x10, 430 }; 431 432 #define UBIFS_FLG_MASK (UBIFS_FLG_BIGLPT|UBIFS_FLG_SPACE_FIXUP|UBIFS_FLG_DOUBLE_HASH|UBIFS_FLG_ENCRYPTION) 433 434 /** 435 * struct ubifs_ch - common header node. 436 * @magic: UBIFS node magic number (%UBIFS_NODE_MAGIC) 437 * @crc: CRC-32 checksum of the node header 438 * @sqnum: sequence number 439 * @len: full node length 440 * @node_type: node type 441 * @group_type: node group type 442 * @padding: reserved for future, zeroes 443 * 444 * Every UBIFS node starts with this common part. If the node has a key, the 445 * key always goes next. 446 */ 447 struct ubifs_ch { 448 __le32 magic; 449 __le32 crc; 450 __le64 sqnum; 451 __le32 len; 452 __u8 node_type; 453 __u8 group_type; 454 __u8 padding[2]; 455 } __packed; 456 457 /** 458 * union ubifs_dev_desc - device node descriptor. 459 * @new: new type device descriptor 460 * @huge: huge type device descriptor 461 * 462 * This data structure describes major/minor numbers of a device node. In an 463 * inode is a device node then its data contains an object of this type. UBIFS 464 * uses standard Linux "new" and "huge" device node encodings. 465 */ 466 union ubifs_dev_desc { 467 __le32 new; 468 __le64 huge; 469 } __packed; 470 471 /** 472 * struct ubifs_ino_node - inode node. 473 * @ch: common header 474 * @key: node key 475 * @creat_sqnum: sequence number at time of creation 476 * @size: inode size in bytes (amount of uncompressed data) 477 * @atime_sec: access time seconds 478 * @ctime_sec: creation time seconds 479 * @mtime_sec: modification time seconds 480 * @atime_nsec: access time nanoseconds 481 * @ctime_nsec: creation time nanoseconds 482 * @mtime_nsec: modification time nanoseconds 483 * @nlink: number of hard links 484 * @uid: owner ID 485 * @gid: group ID 486 * @mode: access flags 487 * @flags: per-inode flags (%UBIFS_COMPR_FL, %UBIFS_SYNC_FL, etc) 488 * @data_len: inode data length 489 * @xattr_cnt: count of extended attributes this inode has 490 * @xattr_size: summarized size of all extended attributes in bytes 491 * @padding1: reserved for future, zeroes 492 * @xattr_names: sum of lengths of all extended attribute names belonging to 493 * this inode 494 * @compr_type: compression type used for this inode 495 * @padding2: reserved for future, zeroes 496 * @data: data attached to the inode 497 * 498 * Note, even though inode compression type is defined by @compr_type, some 499 * nodes of this inode may be compressed with different compressor - this 500 * happens if compression type is changed while the inode already has data 501 * nodes. But @compr_type will be use for further writes to the inode. 502 * 503 * Note, do not forget to amend 'zero_ino_node_unused()' function when changing 504 * the padding fields. 505 */ 506 struct ubifs_ino_node { 507 struct ubifs_ch ch; 508 __u8 key[UBIFS_MAX_KEY_LEN]; 509 __le64 creat_sqnum; 510 __le64 size; 511 __le64 atime_sec; 512 __le64 ctime_sec; 513 __le64 mtime_sec; 514 __le32 atime_nsec; 515 __le32 ctime_nsec; 516 __le32 mtime_nsec; 517 __le32 nlink; 518 __le32 uid; 519 __le32 gid; 520 __le32 mode; 521 __le32 flags; 522 __le32 data_len; 523 __le32 xattr_cnt; 524 __le32 xattr_size; 525 __u8 padding1[4]; /* Watch 'zero_ino_node_unused()' if changing! */ 526 __le32 xattr_names; 527 __le16 compr_type; 528 __u8 padding2[26]; /* Watch 'zero_ino_node_unused()' if changing! */ 529 __u8 data[]; 530 } __packed; 531 532 /** 533 * struct ubifs_dent_node - directory entry node. 534 * @ch: common header 535 * @key: node key 536 * @inum: target inode number 537 * @padding1: reserved for future, zeroes 538 * @type: type of the target inode (%UBIFS_ITYPE_REG, %UBIFS_ITYPE_DIR, etc) 539 * @nlen: name length 540 * @cookie: A 32bits random number, used to construct a 64bits 541 * identifier. 542 * @name: zero-terminated name 543 * 544 * Note, do not forget to amend 'zero_dent_node_unused()' function when 545 * changing the padding fields. 546 */ 547 struct ubifs_dent_node { 548 struct ubifs_ch ch; 549 __u8 key[UBIFS_MAX_KEY_LEN]; 550 __le64 inum; 551 __u8 padding1; 552 __u8 type; 553 __le16 nlen; 554 __le32 cookie; 555 __u8 name[]; 556 } __packed; 557 558 /** 559 * struct ubifs_data_node - data node. 560 * @ch: common header 561 * @key: node key 562 * @size: uncompressed data size in bytes 563 * @compr_type: compression type (%UBIFS_COMPR_NONE, %UBIFS_COMPR_LZO, etc) 564 * @compr_size: compressed data size in bytes, only valid when data is encrypted 565 * @data: data 566 * 567 */ 568 struct ubifs_data_node { 569 struct ubifs_ch ch; 570 __u8 key[UBIFS_MAX_KEY_LEN]; 571 __le32 size; 572 __le16 compr_type; 573 __le16 compr_size; 574 __u8 data[]; 575 } __packed; 576 577 /** 578 * struct ubifs_trun_node - truncation node. 579 * @ch: common header 580 * @inum: truncated inode number 581 * @padding: reserved for future, zeroes 582 * @old_size: size before truncation 583 * @new_size: size after truncation 584 * 585 * This node exists only in the journal and never goes to the main area. Note, 586 * do not forget to amend 'zero_trun_node_unused()' function when changing the 587 * padding fields. 588 */ 589 struct ubifs_trun_node { 590 struct ubifs_ch ch; 591 __le32 inum; 592 __u8 padding[12]; /* Watch 'zero_trun_node_unused()' if changing! */ 593 __le64 old_size; 594 __le64 new_size; 595 } __packed; 596 597 /** 598 * struct ubifs_pad_node - padding node. 599 * @ch: common header 600 * @pad_len: how many bytes after this node are unused (because padded) 601 * @padding: reserved for future, zeroes 602 */ 603 struct ubifs_pad_node { 604 struct ubifs_ch ch; 605 __le32 pad_len; 606 } __packed; 607 608 /** 609 * struct ubifs_sb_node - superblock node. 610 * @ch: common header 611 * @padding: reserved for future, zeroes 612 * @key_hash: type of hash function used in keys 613 * @key_fmt: format of the key 614 * @flags: file-system flags (%UBIFS_FLG_BIGLPT, etc) 615 * @min_io_size: minimal input/output unit size 616 * @leb_size: logical eraseblock size in bytes 617 * @leb_cnt: count of LEBs used by file-system 618 * @max_leb_cnt: maximum count of LEBs used by file-system 619 * @max_bud_bytes: maximum amount of data stored in buds 620 * @log_lebs: log size in logical eraseblocks 621 * @lpt_lebs: number of LEBs used for lprops table 622 * @orph_lebs: number of LEBs used for recording orphans 623 * @jhead_cnt: count of journal heads 624 * @fanout: tree fanout (max. number of links per indexing node) 625 * @lsave_cnt: number of LEB numbers in LPT's save table 626 * @fmt_version: UBIFS on-flash format version 627 * @default_compr: default compression algorithm (%UBIFS_COMPR_LZO, etc) 628 * @padding1: reserved for future, zeroes 629 * @rp_uid: reserve pool UID 630 * @rp_gid: reserve pool GID 631 * @rp_size: size of the reserved pool in bytes 632 * @padding2: reserved for future, zeroes 633 * @time_gran: time granularity in nanoseconds 634 * @uuid: UUID generated when the file system image was created 635 * @ro_compat_version: UBIFS R/O compatibility version 636 */ 637 struct ubifs_sb_node { 638 struct ubifs_ch ch; 639 __u8 padding[2]; 640 __u8 key_hash; 641 __u8 key_fmt; 642 __le32 flags; 643 __le32 min_io_size; 644 __le32 leb_size; 645 __le32 leb_cnt; 646 __le32 max_leb_cnt; 647 __le64 max_bud_bytes; 648 __le32 log_lebs; 649 __le32 lpt_lebs; 650 __le32 orph_lebs; 651 __le32 jhead_cnt; 652 __le32 fanout; 653 __le32 lsave_cnt; 654 __le32 fmt_version; 655 __le16 default_compr; 656 __u8 padding1[2]; 657 __le32 rp_uid; 658 __le32 rp_gid; 659 __le64 rp_size; 660 __le32 time_gran; 661 __u8 uuid[16]; 662 __le32 ro_compat_version; 663 __u8 padding2[3968]; 664 } __packed; 665 666 /** 667 * struct ubifs_mst_node - master node. 668 * @ch: common header 669 * @highest_inum: highest inode number in the committed index 670 * @cmt_no: commit number 671 * @flags: various flags (%UBIFS_MST_DIRTY, etc) 672 * @log_lnum: start of the log 673 * @root_lnum: LEB number of the root indexing node 674 * @root_offs: offset within @root_lnum 675 * @root_len: root indexing node length 676 * @gc_lnum: LEB reserved for garbage collection (%-1 value means the LEB was 677 * not reserved and should be reserved on mount) 678 * @ihead_lnum: LEB number of index head 679 * @ihead_offs: offset of index head 680 * @index_size: size of index on flash 681 * @total_free: total free space in bytes 682 * @total_dirty: total dirty space in bytes 683 * @total_used: total used space in bytes (includes only data LEBs) 684 * @total_dead: total dead space in bytes (includes only data LEBs) 685 * @total_dark: total dark space in bytes (includes only data LEBs) 686 * @lpt_lnum: LEB number of LPT root nnode 687 * @lpt_offs: offset of LPT root nnode 688 * @nhead_lnum: LEB number of LPT head 689 * @nhead_offs: offset of LPT head 690 * @ltab_lnum: LEB number of LPT's own lprops table 691 * @ltab_offs: offset of LPT's own lprops table 692 * @lsave_lnum: LEB number of LPT's save table (big model only) 693 * @lsave_offs: offset of LPT's save table (big model only) 694 * @lscan_lnum: LEB number of last LPT scan 695 * @empty_lebs: number of empty logical eraseblocks 696 * @idx_lebs: number of indexing logical eraseblocks 697 * @leb_cnt: count of LEBs used by file-system 698 * @padding: reserved for future, zeroes 699 */ 700 struct ubifs_mst_node { 701 struct ubifs_ch ch; 702 __le64 highest_inum; 703 __le64 cmt_no; 704 __le32 flags; 705 __le32 log_lnum; 706 __le32 root_lnum; 707 __le32 root_offs; 708 __le32 root_len; 709 __le32 gc_lnum; 710 __le32 ihead_lnum; 711 __le32 ihead_offs; 712 __le64 index_size; 713 __le64 total_free; 714 __le64 total_dirty; 715 __le64 total_used; 716 __le64 total_dead; 717 __le64 total_dark; 718 __le32 lpt_lnum; 719 __le32 lpt_offs; 720 __le32 nhead_lnum; 721 __le32 nhead_offs; 722 __le32 ltab_lnum; 723 __le32 ltab_offs; 724 __le32 lsave_lnum; 725 __le32 lsave_offs; 726 __le32 lscan_lnum; 727 __le32 empty_lebs; 728 __le32 idx_lebs; 729 __le32 leb_cnt; 730 __u8 padding[344]; 731 } __packed; 732 733 /** 734 * struct ubifs_ref_node - logical eraseblock reference node. 735 * @ch: common header 736 * @lnum: the referred logical eraseblock number 737 * @offs: start offset in the referred LEB 738 * @jhead: journal head number 739 * @padding: reserved for future, zeroes 740 */ 741 struct ubifs_ref_node { 742 struct ubifs_ch ch; 743 __le32 lnum; 744 __le32 offs; 745 __le32 jhead; 746 __u8 padding[28]; 747 } __packed; 748 749 /** 750 * struct ubifs_branch - key/reference/length branch 751 * @lnum: LEB number of the target node 752 * @offs: offset within @lnum 753 * @len: target node length 754 * @key: key 755 */ 756 struct ubifs_branch { 757 __le32 lnum; 758 __le32 offs; 759 __le32 len; 760 __u8 key[]; 761 } __packed; 762 763 /** 764 * struct ubifs_idx_node - indexing node. 765 * @ch: common header 766 * @child_cnt: number of child index nodes 767 * @level: tree level 768 * @branches: LEB number / offset / length / key branches 769 */ 770 struct ubifs_idx_node { 771 struct ubifs_ch ch; 772 __le16 child_cnt; 773 __le16 level; 774 __u8 branches[]; 775 } __packed; 776 777 /** 778 * struct ubifs_cs_node - commit start node. 779 * @ch: common header 780 * @cmt_no: commit number 781 */ 782 struct ubifs_cs_node { 783 struct ubifs_ch ch; 784 __le64 cmt_no; 785 } __packed; 786 787 /** 788 * struct ubifs_orph_node - orphan node. 789 * @ch: common header 790 * @cmt_no: commit number (also top bit is set on the last node of the commit) 791 * @inos: inode numbers of orphans 792 */ 793 struct ubifs_orph_node { 794 struct ubifs_ch ch; 795 __le64 cmt_no; 796 __le64 inos[]; 797 } __packed; 798 799 #endif /* __UBIFS_MEDIA_H__ */ 800