1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc. 4 * Copyright (c) 2013 Red Hat, Inc. 5 * All Rights Reserved. 6 */ 7 #ifndef __XFS_DA_FORMAT_H__ 8 #define __XFS_DA_FORMAT_H__ 9 10 /* 11 * This structure is common to both leaf nodes and non-leaf nodes in the Btree. 12 * 13 * It is used to manage a doubly linked list of all blocks at the same 14 * level in the Btree, and to identify which type of block this is. 15 */ 16 #define XFS_DA_NODE_MAGIC 0xfebe /* magic number: non-leaf blocks */ 17 #define XFS_ATTR_LEAF_MAGIC 0xfbee /* magic number: attribute leaf blks */ 18 #define XFS_DIR2_LEAF1_MAGIC 0xd2f1 /* magic number: v2 dirlf single blks */ 19 #define XFS_DIR2_LEAFN_MAGIC 0xd2ff /* magic number: v2 dirlf multi blks */ 20 21 typedef struct xfs_da_blkinfo { 22 __be32 forw; /* previous block in list */ 23 __be32 back; /* following block in list */ 24 __be16 magic; /* validity check on block */ 25 __be16 pad; /* unused */ 26 } xfs_da_blkinfo_t; 27 28 /* 29 * CRC enabled directory structure types 30 * 31 * The headers change size for the additional verification information, but 32 * otherwise the tree layouts and contents are unchanged. Hence the da btree 33 * code can use the struct xfs_da_blkinfo for manipulating the tree links and 34 * magic numbers without modification for both v2 and v3 nodes. 35 */ 36 #define XFS_DA3_NODE_MAGIC 0x3ebe /* magic number: non-leaf blocks */ 37 #define XFS_ATTR3_LEAF_MAGIC 0x3bee /* magic number: attribute leaf blks */ 38 #define XFS_DIR3_LEAF1_MAGIC 0x3df1 /* magic number: v3 dirlf single blks */ 39 #define XFS_DIR3_LEAFN_MAGIC 0x3dff /* magic number: v3 dirlf multi blks */ 40 41 struct xfs_da3_blkinfo { 42 /* 43 * the node link manipulation code relies on the fact that the first 44 * element of this structure is the struct xfs_da_blkinfo so it can 45 * ignore the differences in the rest of the structures. 46 */ 47 struct xfs_da_blkinfo hdr; 48 __be32 crc; /* CRC of block */ 49 __be64 blkno; /* first block of the buffer */ 50 __be64 lsn; /* sequence number of last write */ 51 uuid_t uuid; /* filesystem we belong to */ 52 __be64 owner; /* inode that owns the block */ 53 }; 54 55 /* 56 * This is the structure of the root and intermediate nodes in the Btree. 57 * The leaf nodes are defined above. 58 * 59 * Entries are not packed. 60 * 61 * Since we have duplicate keys, use a binary search but always follow 62 * all match in the block, not just the first match found. 63 */ 64 #define XFS_DA_NODE_MAXDEPTH 5 /* max depth of Btree */ 65 66 typedef struct xfs_da_node_hdr { 67 struct xfs_da_blkinfo info; /* block type, links, etc. */ 68 __be16 __count; /* count of active entries */ 69 __be16 __level; /* level above leaves (leaf == 0) */ 70 } xfs_da_node_hdr_t; 71 72 struct xfs_da3_node_hdr { 73 struct xfs_da3_blkinfo info; /* block type, links, etc. */ 74 __be16 __count; /* count of active entries */ 75 __be16 __level; /* level above leaves (leaf == 0) */ 76 __be32 __pad32; 77 }; 78 79 #define XFS_DA3_NODE_CRC_OFF (offsetof(struct xfs_da3_node_hdr, info.crc)) 80 81 typedef struct xfs_da_node_entry { 82 __be32 hashval; /* hash value for this descendant */ 83 __be32 before; /* Btree block before this key */ 84 } xfs_da_node_entry_t; 85 86 typedef struct xfs_da_intnode { 87 struct xfs_da_node_hdr hdr; 88 struct xfs_da_node_entry __btree[]; 89 } xfs_da_intnode_t; 90 91 struct xfs_da3_intnode { 92 struct xfs_da3_node_hdr hdr; 93 struct xfs_da_node_entry __btree[]; 94 }; 95 96 /* 97 * Directory version 2. 98 * 99 * There are 4 possible formats: 100 * - shortform - embedded into the inode 101 * - single block - data with embedded leaf at the end 102 * - multiple data blocks, single leaf+freeindex block 103 * - data blocks, node and leaf blocks (btree), freeindex blocks 104 * 105 * Note: many node blocks structures and constants are shared with the attr 106 * code and defined in xfs_da_btree.h. 107 */ 108 109 #define XFS_DIR2_BLOCK_MAGIC 0x58443242 /* XD2B: single block dirs */ 110 #define XFS_DIR2_DATA_MAGIC 0x58443244 /* XD2D: multiblock dirs */ 111 #define XFS_DIR2_FREE_MAGIC 0x58443246 /* XD2F: free index blocks */ 112 113 /* 114 * Directory Version 3 With CRCs. 115 * 116 * The tree formats are the same as for version 2 directories. The difference 117 * is in the block header and dirent formats. In many cases the v3 structures 118 * use v2 definitions as they are no different and this makes code sharing much 119 * easier. 120 * 121 * Also, the xfs_dir3_*() functions handle both v2 and v3 formats - if the 122 * format is v2 then they switch to the existing v2 code, or the format is v3 123 * they implement the v3 functionality. This means the existing dir2 is a mix of 124 * xfs_dir2/xfs_dir3 calls and functions. The xfs_dir3 functions are called 125 * where there is a difference in the formats, otherwise the code is unchanged. 126 * 127 * Where it is possible, the code decides what to do based on the magic numbers 128 * in the blocks rather than feature bits in the superblock. This means the code 129 * is as independent of the external XFS code as possible as doesn't require 130 * passing struct xfs_mount pointers into places where it isn't really 131 * necessary. 132 * 133 * Version 3 includes: 134 * 135 * - a larger block header for CRC and identification purposes and so the 136 * offsets of all the structures inside the blocks are different. 137 * 138 * - new magic numbers to be able to detect the v2/v3 types on the fly. 139 */ 140 141 #define XFS_DIR3_BLOCK_MAGIC 0x58444233 /* XDB3: single block dirs */ 142 #define XFS_DIR3_DATA_MAGIC 0x58444433 /* XDD3: multiblock dirs */ 143 #define XFS_DIR3_FREE_MAGIC 0x58444633 /* XDF3: free index blocks */ 144 145 /* 146 * Dirents in version 3 directories have a file type field. Additions to this 147 * list are an on-disk format change, requiring feature bits. Valid values 148 * are as follows: 149 */ 150 #define XFS_DIR3_FT_UNKNOWN 0 151 #define XFS_DIR3_FT_REG_FILE 1 152 #define XFS_DIR3_FT_DIR 2 153 #define XFS_DIR3_FT_CHRDEV 3 154 #define XFS_DIR3_FT_BLKDEV 4 155 #define XFS_DIR3_FT_FIFO 5 156 #define XFS_DIR3_FT_SOCK 6 157 #define XFS_DIR3_FT_SYMLINK 7 158 #define XFS_DIR3_FT_WHT 8 159 160 #define XFS_DIR3_FT_MAX 9 161 162 /* 163 * Byte offset in data block and shortform entry. 164 */ 165 typedef uint16_t xfs_dir2_data_off_t; 166 #define NULLDATAOFF 0xffffU 167 typedef uint xfs_dir2_data_aoff_t; /* argument form */ 168 169 /* 170 * Offset in data space of a data entry. 171 */ 172 typedef uint32_t xfs_dir2_dataptr_t; 173 #define XFS_DIR2_MAX_DATAPTR ((xfs_dir2_dataptr_t)0xffffffff) 174 #define XFS_DIR2_NULL_DATAPTR ((xfs_dir2_dataptr_t)0) 175 176 /* 177 * Byte offset in a directory. 178 */ 179 typedef xfs_off_t xfs_dir2_off_t; 180 181 /* 182 * Directory block number (logical dirblk in file) 183 */ 184 typedef uint32_t xfs_dir2_db_t; 185 186 #define XFS_INO32_SIZE 4 187 #define XFS_INO64_SIZE 8 188 #define XFS_INO64_DIFF (XFS_INO64_SIZE - XFS_INO32_SIZE) 189 190 #define XFS_DIR2_MAX_SHORT_INUM ((xfs_ino_t)0xffffffffULL) 191 192 /* 193 * Directory layout when stored internal to an inode. 194 * 195 * Small directories are packed as tightly as possible so as to fit into the 196 * literal area of the inode. These "shortform" directories consist of a 197 * single xfs_dir2_sf_hdr header followed by zero or more xfs_dir2_sf_entry 198 * structures. Due the different inode number storage size and the variable 199 * length name field in the xfs_dir2_sf_entry all these structure are 200 * variable length, and the accessors in this file should be used to iterate 201 * over them. 202 */ 203 typedef struct xfs_dir2_sf_hdr { 204 uint8_t count; /* count of entries */ 205 uint8_t i8count; /* count of 8-byte inode #s */ 206 uint8_t parent[8]; /* parent dir inode number */ 207 } __packed xfs_dir2_sf_hdr_t; 208 209 typedef struct xfs_dir2_sf_entry { 210 __u8 namelen; /* actual name length */ 211 __u8 offset[2]; /* saved offset */ 212 __u8 name[]; /* name, variable size */ 213 /* 214 * A single byte containing the file type field follows the inode 215 * number for version 3 directory entries. 216 * 217 * A 64-bit or 32-bit inode number follows here, at a variable offset 218 * after the name. 219 */ 220 } __packed xfs_dir2_sf_entry_t; 221 222 static inline int xfs_dir2_sf_hdr_size(int i8count) 223 { 224 return sizeof(struct xfs_dir2_sf_hdr) - 225 (i8count == 0) * XFS_INO64_DIFF; 226 } 227 228 static inline xfs_dir2_data_aoff_t 229 xfs_dir2_sf_get_offset(xfs_dir2_sf_entry_t *sfep) 230 { 231 return get_unaligned_be16(sfep->offset); 232 } 233 234 static inline void 235 xfs_dir2_sf_put_offset(xfs_dir2_sf_entry_t *sfep, xfs_dir2_data_aoff_t off) 236 { 237 put_unaligned_be16(off, sfep->offset); 238 } 239 240 static inline struct xfs_dir2_sf_entry * 241 xfs_dir2_sf_firstentry(struct xfs_dir2_sf_hdr *hdr) 242 { 243 return (struct xfs_dir2_sf_entry *) 244 ((char *)hdr + xfs_dir2_sf_hdr_size(hdr->i8count)); 245 } 246 247 /* 248 * Data block structures. 249 * 250 * A pure data block looks like the following drawing on disk: 251 * 252 * +-------------------------------------------------+ 253 * | xfs_dir2_data_hdr_t | 254 * +-------------------------------------------------+ 255 * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | 256 * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | 257 * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | 258 * | ... | 259 * +-------------------------------------------------+ 260 * | unused space | 261 * +-------------------------------------------------+ 262 * 263 * As all the entries are variable size structures the accessors below should 264 * be used to iterate over them. 265 * 266 * In addition to the pure data blocks for the data and node formats, 267 * most structures are also used for the combined data/freespace "block" 268 * format below. 269 */ 270 271 #define XFS_DIR2_DATA_ALIGN_LOG 3 /* i.e., 8 bytes */ 272 #define XFS_DIR2_DATA_ALIGN (1 << XFS_DIR2_DATA_ALIGN_LOG) 273 #define XFS_DIR2_DATA_FREE_TAG 0xffff 274 #define XFS_DIR2_DATA_FD_COUNT 3 275 276 /* 277 * Directory address space divided into sections, 278 * spaces separated by 32GB. 279 */ 280 #define XFS_DIR2_SPACE_SIZE (1ULL << (32 + XFS_DIR2_DATA_ALIGN_LOG)) 281 #define XFS_DIR2_DATA_SPACE 0 282 #define XFS_DIR2_DATA_OFFSET (XFS_DIR2_DATA_SPACE * XFS_DIR2_SPACE_SIZE) 283 284 /* 285 * Describe a free area in the data block. 286 * 287 * The freespace will be formatted as a xfs_dir2_data_unused_t. 288 */ 289 typedef struct xfs_dir2_data_free { 290 __be16 offset; /* start of freespace */ 291 __be16 length; /* length of freespace */ 292 } xfs_dir2_data_free_t; 293 294 /* 295 * Header for the data blocks. 296 * 297 * The code knows that XFS_DIR2_DATA_FD_COUNT is 3. 298 */ 299 typedef struct xfs_dir2_data_hdr { 300 __be32 magic; /* XFS_DIR2_DATA_MAGIC or */ 301 /* XFS_DIR2_BLOCK_MAGIC */ 302 xfs_dir2_data_free_t bestfree[XFS_DIR2_DATA_FD_COUNT]; 303 } xfs_dir2_data_hdr_t; 304 305 /* 306 * define a structure for all the verification fields we are adding to the 307 * directory block structures. This will be used in several structures. 308 * The magic number must be the first entry to align with all the dir2 309 * structures so we determine how to decode them just by the magic number. 310 */ 311 struct xfs_dir3_blk_hdr { 312 __be32 magic; /* magic number */ 313 __be32 crc; /* CRC of block */ 314 __be64 blkno; /* first block of the buffer */ 315 __be64 lsn; /* sequence number of last write */ 316 uuid_t uuid; /* filesystem we belong to */ 317 __be64 owner; /* inode that owns the block */ 318 }; 319 320 struct xfs_dir3_data_hdr { 321 struct xfs_dir3_blk_hdr hdr; 322 xfs_dir2_data_free_t best_free[XFS_DIR2_DATA_FD_COUNT]; 323 __be32 pad; /* 64 bit alignment */ 324 }; 325 326 #define XFS_DIR3_DATA_CRC_OFF offsetof(struct xfs_dir3_data_hdr, hdr.crc) 327 328 /* 329 * Active entry in a data block. 330 * 331 * Aligned to 8 bytes. After the variable length name field there is a 332 * 2 byte tag field, which can be accessed using xfs_dir3_data_entry_tag_p. 333 * 334 * For dir3 structures, there is file type field between the name and the tag. 335 * This can only be manipulated by helper functions. It is packed hard against 336 * the end of the name so any padding for rounding is between the file type and 337 * the tag. 338 */ 339 typedef struct xfs_dir2_data_entry { 340 __be64 inumber; /* inode number */ 341 __u8 namelen; /* name length */ 342 __u8 name[]; /* name bytes, no null */ 343 /* __u8 filetype; */ /* type of inode we point to */ 344 /* __be16 tag; */ /* starting offset of us */ 345 } xfs_dir2_data_entry_t; 346 347 /* 348 * Unused entry in a data block. 349 * 350 * Aligned to 8 bytes. Tag appears as the last 2 bytes and must be accessed 351 * using xfs_dir2_data_unused_tag_p. 352 */ 353 typedef struct xfs_dir2_data_unused { 354 __be16 freetag; /* XFS_DIR2_DATA_FREE_TAG */ 355 __be16 length; /* total free length */ 356 /* variable offset */ 357 __be16 tag; /* starting offset of us */ 358 } xfs_dir2_data_unused_t; 359 360 /* 361 * Pointer to a freespace's tag word. 362 */ 363 static inline __be16 * 364 xfs_dir2_data_unused_tag_p(struct xfs_dir2_data_unused *dup) 365 { 366 return (__be16 *)((char *)dup + 367 be16_to_cpu(dup->length) - sizeof(__be16)); 368 } 369 370 /* 371 * Leaf block structures. 372 * 373 * A pure leaf block looks like the following drawing on disk: 374 * 375 * +---------------------------+ 376 * | xfs_dir2_leaf_hdr_t | 377 * +---------------------------+ 378 * | xfs_dir2_leaf_entry_t | 379 * | xfs_dir2_leaf_entry_t | 380 * | xfs_dir2_leaf_entry_t | 381 * | xfs_dir2_leaf_entry_t | 382 * | ... | 383 * +---------------------------+ 384 * | xfs_dir2_data_off_t | 385 * | xfs_dir2_data_off_t | 386 * | xfs_dir2_data_off_t | 387 * | ... | 388 * +---------------------------+ 389 * | xfs_dir2_leaf_tail_t | 390 * +---------------------------+ 391 * 392 * The xfs_dir2_data_off_t members (bests) and tail are at the end of the block 393 * for single-leaf (magic = XFS_DIR2_LEAF1_MAGIC) blocks only, but not present 394 * for directories with separate leaf nodes and free space blocks 395 * (magic = XFS_DIR2_LEAFN_MAGIC). 396 * 397 * As all the entries are variable size structures the accessors below should 398 * be used to iterate over them. 399 */ 400 401 /* 402 * Offset of the leaf/node space. First block in this space 403 * is the btree root. 404 */ 405 #define XFS_DIR2_LEAF_SPACE 1 406 #define XFS_DIR2_LEAF_OFFSET (XFS_DIR2_LEAF_SPACE * XFS_DIR2_SPACE_SIZE) 407 408 /* 409 * Leaf block header. 410 */ 411 typedef struct xfs_dir2_leaf_hdr { 412 xfs_da_blkinfo_t info; /* header for da routines */ 413 __be16 count; /* count of entries */ 414 __be16 stale; /* count of stale entries */ 415 } xfs_dir2_leaf_hdr_t; 416 417 struct xfs_dir3_leaf_hdr { 418 struct xfs_da3_blkinfo info; /* header for da routines */ 419 __be16 count; /* count of entries */ 420 __be16 stale; /* count of stale entries */ 421 __be32 pad; /* 64 bit alignment */ 422 }; 423 424 /* 425 * Leaf block entry. 426 */ 427 typedef struct xfs_dir2_leaf_entry { 428 __be32 hashval; /* hash value of name */ 429 __be32 address; /* address of data entry */ 430 } xfs_dir2_leaf_entry_t; 431 432 /* 433 * Leaf block tail. 434 */ 435 typedef struct xfs_dir2_leaf_tail { 436 __be32 bestcount; 437 } xfs_dir2_leaf_tail_t; 438 439 /* 440 * Leaf block. 441 */ 442 typedef struct xfs_dir2_leaf { 443 xfs_dir2_leaf_hdr_t hdr; /* leaf header */ 444 xfs_dir2_leaf_entry_t __ents[]; /* entries */ 445 } xfs_dir2_leaf_t; 446 447 struct xfs_dir3_leaf { 448 struct xfs_dir3_leaf_hdr hdr; /* leaf header */ 449 struct xfs_dir2_leaf_entry __ents[]; /* entries */ 450 }; 451 452 #define XFS_DIR3_LEAF_CRC_OFF offsetof(struct xfs_dir3_leaf_hdr, info.crc) 453 454 /* 455 * Get address of the bests array in the single-leaf block. 456 */ 457 static inline __be16 * 458 xfs_dir2_leaf_bests_p(struct xfs_dir2_leaf_tail *ltp) 459 { 460 return (__be16 *)ltp - be32_to_cpu(ltp->bestcount); 461 } 462 463 /* 464 * Free space block definitions for the node format. 465 */ 466 467 /* 468 * Offset of the freespace index. 469 */ 470 #define XFS_DIR2_FREE_SPACE 2 471 #define XFS_DIR2_FREE_OFFSET (XFS_DIR2_FREE_SPACE * XFS_DIR2_SPACE_SIZE) 472 473 typedef struct xfs_dir2_free_hdr { 474 __be32 magic; /* XFS_DIR2_FREE_MAGIC */ 475 __be32 firstdb; /* db of first entry */ 476 __be32 nvalid; /* count of valid entries */ 477 __be32 nused; /* count of used entries */ 478 } xfs_dir2_free_hdr_t; 479 480 typedef struct xfs_dir2_free { 481 xfs_dir2_free_hdr_t hdr; /* block header */ 482 __be16 bests[]; /* best free counts */ 483 /* unused entries are -1 */ 484 } xfs_dir2_free_t; 485 486 struct xfs_dir3_free_hdr { 487 struct xfs_dir3_blk_hdr hdr; 488 __be32 firstdb; /* db of first entry */ 489 __be32 nvalid; /* count of valid entries */ 490 __be32 nused; /* count of used entries */ 491 __be32 pad; /* 64 bit alignment */ 492 }; 493 494 struct xfs_dir3_free { 495 struct xfs_dir3_free_hdr hdr; 496 __be16 bests[]; /* best free counts */ 497 /* unused entries are -1 */ 498 }; 499 500 #define XFS_DIR3_FREE_CRC_OFF offsetof(struct xfs_dir3_free, hdr.hdr.crc) 501 502 /* 503 * Single block format. 504 * 505 * The single block format looks like the following drawing on disk: 506 * 507 * +-------------------------------------------------+ 508 * | xfs_dir2_data_hdr_t | 509 * +-------------------------------------------------+ 510 * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | 511 * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | 512 * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t : 513 * | ... | 514 * +-------------------------------------------------+ 515 * | unused space | 516 * +-------------------------------------------------+ 517 * | ... | 518 * | xfs_dir2_leaf_entry_t | 519 * | xfs_dir2_leaf_entry_t | 520 * +-------------------------------------------------+ 521 * | xfs_dir2_block_tail_t | 522 * +-------------------------------------------------+ 523 * 524 * As all the entries are variable size structures the accessors below should 525 * be used to iterate over them. 526 */ 527 528 typedef struct xfs_dir2_block_tail { 529 __be32 count; /* count of leaf entries */ 530 __be32 stale; /* count of stale lf entries */ 531 } xfs_dir2_block_tail_t; 532 533 /* 534 * Pointer to the leaf entries embedded in a data block (1-block format) 535 */ 536 static inline struct xfs_dir2_leaf_entry * 537 xfs_dir2_block_leaf_p(struct xfs_dir2_block_tail *btp) 538 { 539 return ((struct xfs_dir2_leaf_entry *)btp) - be32_to_cpu(btp->count); 540 } 541 542 543 /* 544 * Attribute storage layout 545 * 546 * Attribute lists are structured around Btrees where all the data 547 * elements are in the leaf nodes. Attribute names are hashed into an int, 548 * then that int is used as the index into the Btree. Since the hashval 549 * of an attribute name may not be unique, we may have duplicate keys. The 550 * internal links in the Btree are logical block offsets into the file. 551 * 552 * Struct leaf_entry's are packed from the top. Name/values grow from the 553 * bottom but are not packed. The freemap contains run-length-encoded entries 554 * for the free bytes after the leaf_entry's, but only the N largest such, 555 * smaller runs are dropped. When the freemap doesn't show enough space 556 * for an allocation, we compact the name/value area and try again. If we 557 * still don't have enough space, then we have to split the block. The 558 * name/value structs (both local and remote versions) must be 32bit aligned. 559 * 560 * Since we have duplicate hash keys, for each key that matches, compare 561 * the actual name string. The root and intermediate node search always 562 * takes the first-in-the-block key match found, so we should only have 563 * to work "forw"ard. If none matches, continue with the "forw"ard leaf 564 * nodes until the hash key changes or the attribute name is found. 565 * 566 * We store the fact that an attribute is a ROOT/USER/SECURE attribute in 567 * the leaf_entry. The namespaces are independent only because we also look 568 * at the namespace bit when we are looking for a matching attribute name. 569 * 570 * We also store an "incomplete" bit in the leaf_entry. It shows that an 571 * attribute is in the middle of being created and should not be shown to 572 * the user if we crash during the time that the bit is set. We clear the 573 * bit when we have finished setting up the attribute. We do this because 574 * we cannot create some large attributes inside a single transaction, and we 575 * need some indication that we weren't finished if we crash in the middle. 576 */ 577 #define XFS_ATTR_LEAF_MAPSIZE 3 /* how many freespace slots */ 578 579 /* 580 * Entries are packed toward the top as tight as possible. 581 */ 582 struct xfs_attr_shortform { 583 struct xfs_attr_sf_hdr { /* constant-structure header block */ 584 __be16 totsize; /* total bytes in shortform list */ 585 __u8 count; /* count of active entries */ 586 __u8 padding; 587 } hdr; 588 struct xfs_attr_sf_entry { 589 uint8_t namelen; /* actual length of name (no NULL) */ 590 uint8_t valuelen; /* actual length of value (no NULL) */ 591 uint8_t flags; /* flags bits (see xfs_attr_leaf.h) */ 592 uint8_t nameval[]; /* name & value bytes concatenated */ 593 } list[1]; /* variable sized array */ 594 }; 595 596 typedef struct xfs_attr_leaf_map { /* RLE map of free bytes */ 597 __be16 base; /* base of free region */ 598 __be16 size; /* length of free region */ 599 } xfs_attr_leaf_map_t; 600 601 typedef struct xfs_attr_leaf_hdr { /* constant-structure header block */ 602 xfs_da_blkinfo_t info; /* block type, links, etc. */ 603 __be16 count; /* count of active leaf_entry's */ 604 __be16 usedbytes; /* num bytes of names/values stored */ 605 __be16 firstused; /* first used byte in name area */ 606 __u8 holes; /* != 0 if blk needs compaction */ 607 __u8 pad1; 608 xfs_attr_leaf_map_t freemap[XFS_ATTR_LEAF_MAPSIZE]; 609 /* N largest free regions */ 610 } xfs_attr_leaf_hdr_t; 611 612 typedef struct xfs_attr_leaf_entry { /* sorted on key, not name */ 613 __be32 hashval; /* hash value of name */ 614 __be16 nameidx; /* index into buffer of name/value */ 615 __u8 flags; /* LOCAL/ROOT/SECURE/INCOMPLETE flag */ 616 __u8 pad2; /* unused pad byte */ 617 } xfs_attr_leaf_entry_t; 618 619 typedef struct xfs_attr_leaf_name_local { 620 __be16 valuelen; /* number of bytes in value */ 621 __u8 namelen; /* length of name bytes */ 622 __u8 nameval[1]; /* name/value bytes */ 623 } xfs_attr_leaf_name_local_t; 624 625 typedef struct xfs_attr_leaf_name_remote { 626 __be32 valueblk; /* block number of value bytes */ 627 __be32 valuelen; /* number of bytes in value */ 628 __u8 namelen; /* length of name bytes */ 629 __u8 name[1]; /* name bytes */ 630 } xfs_attr_leaf_name_remote_t; 631 632 typedef struct xfs_attr_leafblock { 633 xfs_attr_leaf_hdr_t hdr; /* constant-structure header block */ 634 xfs_attr_leaf_entry_t entries[1]; /* sorted on key, not name */ 635 /* 636 * The rest of the block contains the following structures after the 637 * leaf entries, growing from the bottom up. The variables are never 638 * referenced and definining them can actually make gcc optimize away 639 * accesses to the 'entries' array above index 0 so don't do that. 640 * 641 * xfs_attr_leaf_name_local_t namelist; 642 * xfs_attr_leaf_name_remote_t valuelist; 643 */ 644 } xfs_attr_leafblock_t; 645 646 /* 647 * CRC enabled leaf structures. Called "version 3" structures to match the 648 * version number of the directory and dablk structures for this feature, and 649 * attr2 is already taken by the variable inode attribute fork size feature. 650 */ 651 struct xfs_attr3_leaf_hdr { 652 struct xfs_da3_blkinfo info; 653 __be16 count; 654 __be16 usedbytes; 655 __be16 firstused; 656 __u8 holes; 657 __u8 pad1; 658 struct xfs_attr_leaf_map freemap[XFS_ATTR_LEAF_MAPSIZE]; 659 __be32 pad2; /* 64 bit alignment */ 660 }; 661 662 #define XFS_ATTR3_LEAF_CRC_OFF (offsetof(struct xfs_attr3_leaf_hdr, info.crc)) 663 664 struct xfs_attr3_leafblock { 665 struct xfs_attr3_leaf_hdr hdr; 666 struct xfs_attr_leaf_entry entries[1]; 667 668 /* 669 * The rest of the block contains the following structures after the 670 * leaf entries, growing from the bottom up. The variables are never 671 * referenced, the locations accessed purely from helper functions. 672 * 673 * struct xfs_attr_leaf_name_local 674 * struct xfs_attr_leaf_name_remote 675 */ 676 }; 677 678 /* 679 * Special value to represent fs block size in the leaf header firstused field. 680 * Only used when block size overflows the 2-bytes available on disk. 681 */ 682 #define XFS_ATTR3_LEAF_NULLOFF 0 683 684 /* 685 * Flags used in the leaf_entry[i].flags field. 686 */ 687 #define XFS_ATTR_LOCAL_BIT 0 /* attr is stored locally */ 688 #define XFS_ATTR_ROOT_BIT 1 /* limit access to trusted attrs */ 689 #define XFS_ATTR_SECURE_BIT 2 /* limit access to secure attrs */ 690 #define XFS_ATTR_INCOMPLETE_BIT 7 /* attr in middle of create/delete */ 691 #define XFS_ATTR_LOCAL (1 << XFS_ATTR_LOCAL_BIT) 692 #define XFS_ATTR_ROOT (1 << XFS_ATTR_ROOT_BIT) 693 #define XFS_ATTR_SECURE (1 << XFS_ATTR_SECURE_BIT) 694 #define XFS_ATTR_INCOMPLETE (1 << XFS_ATTR_INCOMPLETE_BIT) 695 #define XFS_ATTR_NSP_ONDISK_MASK (XFS_ATTR_ROOT | XFS_ATTR_SECURE) 696 697 /* 698 * Alignment for namelist and valuelist entries (since they are mixed 699 * there can be only one alignment value) 700 */ 701 #define XFS_ATTR_LEAF_NAME_ALIGN ((uint)sizeof(xfs_dablk_t)) 702 703 static inline int 704 xfs_attr3_leaf_hdr_size(struct xfs_attr_leafblock *leafp) 705 { 706 if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) 707 return sizeof(struct xfs_attr3_leaf_hdr); 708 return sizeof(struct xfs_attr_leaf_hdr); 709 } 710 711 static inline struct xfs_attr_leaf_entry * 712 xfs_attr3_leaf_entryp(xfs_attr_leafblock_t *leafp) 713 { 714 if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) 715 return &((struct xfs_attr3_leafblock *)leafp)->entries[0]; 716 return &leafp->entries[0]; 717 } 718 719 /* 720 * Cast typed pointers for "local" and "remote" name/value structs. 721 */ 722 static inline char * 723 xfs_attr3_leaf_name(xfs_attr_leafblock_t *leafp, int idx) 724 { 725 struct xfs_attr_leaf_entry *entries = xfs_attr3_leaf_entryp(leafp); 726 727 return &((char *)leafp)[be16_to_cpu(entries[idx].nameidx)]; 728 } 729 730 static inline xfs_attr_leaf_name_remote_t * 731 xfs_attr3_leaf_name_remote(xfs_attr_leafblock_t *leafp, int idx) 732 { 733 return (xfs_attr_leaf_name_remote_t *)xfs_attr3_leaf_name(leafp, idx); 734 } 735 736 static inline xfs_attr_leaf_name_local_t * 737 xfs_attr3_leaf_name_local(xfs_attr_leafblock_t *leafp, int idx) 738 { 739 return (xfs_attr_leaf_name_local_t *)xfs_attr3_leaf_name(leafp, idx); 740 } 741 742 /* 743 * Calculate total bytes used (including trailing pad for alignment) for 744 * a "local" name/value structure, a "remote" name/value structure, and 745 * a pointer which might be either. 746 */ 747 static inline int xfs_attr_leaf_entsize_remote(int nlen) 748 { 749 return round_up(sizeof(struct xfs_attr_leaf_name_remote) - 1 + 750 nlen, XFS_ATTR_LEAF_NAME_ALIGN); 751 } 752 753 static inline int xfs_attr_leaf_entsize_local(int nlen, int vlen) 754 { 755 return round_up(sizeof(struct xfs_attr_leaf_name_local) - 1 + 756 nlen + vlen, XFS_ATTR_LEAF_NAME_ALIGN); 757 } 758 759 static inline int xfs_attr_leaf_entsize_local_max(int bsize) 760 { 761 return (((bsize) >> 1) + ((bsize) >> 2)); 762 } 763 764 765 766 /* 767 * Remote attribute block format definition 768 * 769 * There is one of these headers per filesystem block in a remote attribute. 770 * This is done to ensure there is a 1:1 mapping between the attribute value 771 * length and the number of blocks needed to store the attribute. This makes the 772 * verification of a buffer a little more complex, but greatly simplifies the 773 * allocation, reading and writing of these attributes as we don't have to guess 774 * the number of blocks needed to store the attribute data. 775 */ 776 #define XFS_ATTR3_RMT_MAGIC 0x5841524d /* XARM */ 777 778 struct xfs_attr3_rmt_hdr { 779 __be32 rm_magic; 780 __be32 rm_offset; 781 __be32 rm_bytes; 782 __be32 rm_crc; 783 uuid_t rm_uuid; 784 __be64 rm_owner; 785 __be64 rm_blkno; 786 __be64 rm_lsn; 787 }; 788 789 #define XFS_ATTR3_RMT_CRC_OFF offsetof(struct xfs_attr3_rmt_hdr, rm_crc) 790 791 #define XFS_ATTR3_RMT_BUF_SPACE(mp, bufsize) \ 792 ((bufsize) - (xfs_sb_version_hascrc(&(mp)->m_sb) ? \ 793 sizeof(struct xfs_attr3_rmt_hdr) : 0)) 794 795 /* Number of bytes in a directory block. */ 796 static inline unsigned int xfs_dir2_dirblock_bytes(struct xfs_sb *sbp) 797 { 798 return 1 << (sbp->sb_blocklog + sbp->sb_dirblklog); 799 } 800 801 xfs_failaddr_t xfs_da3_blkinfo_verify(struct xfs_buf *bp, 802 struct xfs_da3_blkinfo *hdr3); 803 804 #endif /* __XFS_DA_FORMAT_H__ */ 805