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 21typedef 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: v2 dirlf single blks */ 39#define XFS_DIR3_LEAFN_MAGIC 0x3dff /* magic number: v2 dirlf multi blks */ 40 41struct 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 66typedef 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 72struct 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 81typedef 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 86typedef struct xfs_da_intnode { 87 struct xfs_da_node_hdr hdr; 88 struct xfs_da_node_entry __btree[]; 89} xfs_da_intnode_t; 90 91struct xfs_da3_intnode { 92 struct xfs_da3_node_hdr hdr; 93 struct xfs_da_node_entry __btree[]; 94}; 95 96/* 97 * In-core version of the node header to abstract the differences in the v2 and 98 * v3 disk format of the headers. Callers need to convert to/from disk format as 99 * appropriate. 100 */ 101struct xfs_da3_icnode_hdr { 102 uint32_t forw; 103 uint32_t back; 104 uint16_t magic; 105 uint16_t count; 106 uint16_t level; 107}; 108 109/* 110 * Directory version 2. 111 * 112 * There are 4 possible formats: 113 * - shortform - embedded into the inode 114 * - single block - data with embedded leaf at the end 115 * - multiple data blocks, single leaf+freeindex block 116 * - data blocks, node and leaf blocks (btree), freeindex blocks 117 * 118 * Note: many node blocks structures and constants are shared with the attr 119 * code and defined in xfs_da_btree.h. 120 */ 121 122#define XFS_DIR2_BLOCK_MAGIC 0x58443242 /* XD2B: single block dirs */ 123#define XFS_DIR2_DATA_MAGIC 0x58443244 /* XD2D: multiblock dirs */ 124#define XFS_DIR2_FREE_MAGIC 0x58443246 /* XD2F: free index blocks */ 125 126/* 127 * Directory Version 3 With CRCs. 128 * 129 * The tree formats are the same as for version 2 directories. The difference 130 * is in the block header and dirent formats. In many cases the v3 structures 131 * use v2 definitions as they are no different and this makes code sharing much 132 * easier. 133 * 134 * Also, the xfs_dir3_*() functions handle both v2 and v3 formats - if the 135 * format is v2 then they switch to the existing v2 code, or the format is v3 136 * they implement the v3 functionality. This means the existing dir2 is a mix of 137 * xfs_dir2/xfs_dir3 calls and functions. The xfs_dir3 functions are called 138 * where there is a difference in the formats, otherwise the code is unchanged. 139 * 140 * Where it is possible, the code decides what to do based on the magic numbers 141 * in the blocks rather than feature bits in the superblock. This means the code 142 * is as independent of the external XFS code as possible as doesn't require 143 * passing struct xfs_mount pointers into places where it isn't really 144 * necessary. 145 * 146 * Version 3 includes: 147 * 148 * - a larger block header for CRC and identification purposes and so the 149 * offsets of all the structures inside the blocks are different. 150 * 151 * - new magic numbers to be able to detect the v2/v3 types on the fly. 152 */ 153 154#define XFS_DIR3_BLOCK_MAGIC 0x58444233 /* XDB3: single block dirs */ 155#define XFS_DIR3_DATA_MAGIC 0x58444433 /* XDD3: multiblock dirs */ 156#define XFS_DIR3_FREE_MAGIC 0x58444633 /* XDF3: free index blocks */ 157 158/* 159 * Dirents in version 3 directories have a file type field. Additions to this 160 * list are an on-disk format change, requiring feature bits. Valid values 161 * are as follows: 162 */ 163#define XFS_DIR3_FT_UNKNOWN 0 164#define XFS_DIR3_FT_REG_FILE 1 165#define XFS_DIR3_FT_DIR 2 166#define XFS_DIR3_FT_CHRDEV 3 167#define XFS_DIR3_FT_BLKDEV 4 168#define XFS_DIR3_FT_FIFO 5 169#define XFS_DIR3_FT_SOCK 6 170#define XFS_DIR3_FT_SYMLINK 7 171#define XFS_DIR3_FT_WHT 8 172 173#define XFS_DIR3_FT_MAX 9 174 175/* 176 * Byte offset in data block and shortform entry. 177 */ 178typedef uint16_t xfs_dir2_data_off_t; 179#define NULLDATAOFF 0xffffU 180typedef uint xfs_dir2_data_aoff_t; /* argument form */ 181 182/* 183 * Offset in data space of a data entry. 184 */ 185typedef uint32_t xfs_dir2_dataptr_t; 186#define XFS_DIR2_MAX_DATAPTR ((xfs_dir2_dataptr_t)0xffffffff) 187#define XFS_DIR2_NULL_DATAPTR ((xfs_dir2_dataptr_t)0) 188 189/* 190 * Byte offset in a directory. 191 */ 192typedef xfs_off_t xfs_dir2_off_t; 193 194/* 195 * Directory block number (logical dirblk in file) 196 */ 197typedef uint32_t xfs_dir2_db_t; 198 199#define XFS_INO32_SIZE 4 200#define XFS_INO64_SIZE 8 201#define XFS_INO64_DIFF (XFS_INO64_SIZE - XFS_INO32_SIZE) 202 203#define XFS_DIR2_MAX_SHORT_INUM ((xfs_ino_t)0xffffffffULL) 204 205/* 206 * Directory layout when stored internal to an inode. 207 * 208 * Small directories are packed as tightly as possible so as to fit into the 209 * literal area of the inode. These "shortform" directories consist of a 210 * single xfs_dir2_sf_hdr header followed by zero or more xfs_dir2_sf_entry 211 * structures. Due the different inode number storage size and the variable 212 * length name field in the xfs_dir2_sf_entry all these structure are 213 * variable length, and the accessors in this file should be used to iterate 214 * over them. 215 */ 216typedef struct xfs_dir2_sf_hdr { 217 uint8_t count; /* count of entries */ 218 uint8_t i8count; /* count of 8-byte inode #s */ 219 uint8_t parent[8]; /* parent dir inode number */ 220} __packed xfs_dir2_sf_hdr_t; 221 222typedef struct xfs_dir2_sf_entry { 223 __u8 namelen; /* actual name length */ 224 __u8 offset[2]; /* saved offset */ 225 __u8 name[]; /* name, variable size */ 226 /* 227 * A single byte containing the file type field follows the inode 228 * number for version 3 directory entries. 229 * 230 * A 64-bit or 32-bit inode number follows here, at a variable offset 231 * after the name. 232 */ 233} xfs_dir2_sf_entry_t; 234 235static inline int xfs_dir2_sf_hdr_size(int i8count) 236{ 237 return sizeof(struct xfs_dir2_sf_hdr) - 238 (i8count == 0) * XFS_INO64_DIFF; 239} 240 241static inline xfs_dir2_data_aoff_t 242xfs_dir2_sf_get_offset(xfs_dir2_sf_entry_t *sfep) 243{ 244 return get_unaligned_be16(sfep->offset); 245} 246 247static inline void 248xfs_dir2_sf_put_offset(xfs_dir2_sf_entry_t *sfep, xfs_dir2_data_aoff_t off) 249{ 250 put_unaligned_be16(off, sfep->offset); 251} 252 253static inline struct xfs_dir2_sf_entry * 254xfs_dir2_sf_firstentry(struct xfs_dir2_sf_hdr *hdr) 255{ 256 return (struct xfs_dir2_sf_entry *) 257 ((char *)hdr + xfs_dir2_sf_hdr_size(hdr->i8count)); 258} 259 260/* 261 * Data block structures. 262 * 263 * A pure data block looks like the following drawing on disk: 264 * 265 * +-------------------------------------------------+ 266 * | xfs_dir2_data_hdr_t | 267 * +-------------------------------------------------+ 268 * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | 269 * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | 270 * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | 271 * | ... | 272 * +-------------------------------------------------+ 273 * | unused space | 274 * +-------------------------------------------------+ 275 * 276 * As all the entries are variable size structures the accessors below should 277 * be used to iterate over them. 278 * 279 * In addition to the pure data blocks for the data and node formats, 280 * most structures are also used for the combined data/freespace "block" 281 * format below. 282 */ 283 284#define XFS_DIR2_DATA_ALIGN_LOG 3 /* i.e., 8 bytes */ 285#define XFS_DIR2_DATA_ALIGN (1 << XFS_DIR2_DATA_ALIGN_LOG) 286#define XFS_DIR2_DATA_FREE_TAG 0xffff 287#define XFS_DIR2_DATA_FD_COUNT 3 288 289/* 290 * Directory address space divided into sections, 291 * spaces separated by 32GB. 292 */ 293#define XFS_DIR2_SPACE_SIZE (1ULL << (32 + XFS_DIR2_DATA_ALIGN_LOG)) 294#define XFS_DIR2_DATA_SPACE 0 295#define XFS_DIR2_DATA_OFFSET (XFS_DIR2_DATA_SPACE * XFS_DIR2_SPACE_SIZE) 296 297/* 298 * Describe a free area in the data block. 299 * 300 * The freespace will be formatted as a xfs_dir2_data_unused_t. 301 */ 302typedef struct xfs_dir2_data_free { 303 __be16 offset; /* start of freespace */ 304 __be16 length; /* length of freespace */ 305} xfs_dir2_data_free_t; 306 307/* 308 * Header for the data blocks. 309 * 310 * The code knows that XFS_DIR2_DATA_FD_COUNT is 3. 311 */ 312typedef struct xfs_dir2_data_hdr { 313 __be32 magic; /* XFS_DIR2_DATA_MAGIC or */ 314 /* XFS_DIR2_BLOCK_MAGIC */ 315 xfs_dir2_data_free_t bestfree[XFS_DIR2_DATA_FD_COUNT]; 316} xfs_dir2_data_hdr_t; 317 318/* 319 * define a structure for all the verification fields we are adding to the 320 * directory block structures. This will be used in several structures. 321 * The magic number must be the first entry to align with all the dir2 322 * structures so we determine how to decode them just by the magic number. 323 */ 324struct xfs_dir3_blk_hdr { 325 __be32 magic; /* magic number */ 326 __be32 crc; /* CRC of block */ 327 __be64 blkno; /* first block of the buffer */ 328 __be64 lsn; /* sequence number of last write */ 329 uuid_t uuid; /* filesystem we belong to */ 330 __be64 owner; /* inode that owns the block */ 331}; 332 333struct xfs_dir3_data_hdr { 334 struct xfs_dir3_blk_hdr hdr; 335 xfs_dir2_data_free_t best_free[XFS_DIR2_DATA_FD_COUNT]; 336 __be32 pad; /* 64 bit alignment */ 337}; 338 339#define XFS_DIR3_DATA_CRC_OFF offsetof(struct xfs_dir3_data_hdr, hdr.crc) 340 341/* 342 * Active entry in a data block. 343 * 344 * Aligned to 8 bytes. After the variable length name field there is a 345 * 2 byte tag field, which can be accessed using xfs_dir3_data_entry_tag_p. 346 * 347 * For dir3 structures, there is file type field between the name and the tag. 348 * This can only be manipulated by helper functions. It is packed hard against 349 * the end of the name so any padding for rounding is between the file type and 350 * the tag. 351 */ 352typedef struct xfs_dir2_data_entry { 353 __be64 inumber; /* inode number */ 354 __u8 namelen; /* name length */ 355 __u8 name[]; /* name bytes, no null */ 356 /* __u8 filetype; */ /* type of inode we point to */ 357 /* __be16 tag; */ /* starting offset of us */ 358} xfs_dir2_data_entry_t; 359 360/* 361 * Unused entry in a data block. 362 * 363 * Aligned to 8 bytes. Tag appears as the last 2 bytes and must be accessed 364 * using xfs_dir2_data_unused_tag_p. 365 */ 366typedef struct xfs_dir2_data_unused { 367 __be16 freetag; /* XFS_DIR2_DATA_FREE_TAG */ 368 __be16 length; /* total free length */ 369 /* variable offset */ 370 __be16 tag; /* starting offset of us */ 371} xfs_dir2_data_unused_t; 372 373/* 374 * Pointer to a freespace's tag word. 375 */ 376static inline __be16 * 377xfs_dir2_data_unused_tag_p(struct xfs_dir2_data_unused *dup) 378{ 379 return (__be16 *)((char *)dup + 380 be16_to_cpu(dup->length) - sizeof(__be16)); 381} 382 383/* 384 * Leaf block structures. 385 * 386 * A pure leaf block looks like the following drawing on disk: 387 * 388 * +---------------------------+ 389 * | xfs_dir2_leaf_hdr_t | 390 * +---------------------------+ 391 * | xfs_dir2_leaf_entry_t | 392 * | xfs_dir2_leaf_entry_t | 393 * | xfs_dir2_leaf_entry_t | 394 * | xfs_dir2_leaf_entry_t | 395 * | ... | 396 * +---------------------------+ 397 * | xfs_dir2_data_off_t | 398 * | xfs_dir2_data_off_t | 399 * | xfs_dir2_data_off_t | 400 * | ... | 401 * +---------------------------+ 402 * | xfs_dir2_leaf_tail_t | 403 * +---------------------------+ 404 * 405 * The xfs_dir2_data_off_t members (bests) and tail are at the end of the block 406 * for single-leaf (magic = XFS_DIR2_LEAF1_MAGIC) blocks only, but not present 407 * for directories with separate leaf nodes and free space blocks 408 * (magic = XFS_DIR2_LEAFN_MAGIC). 409 * 410 * As all the entries are variable size structures the accessors below should 411 * be used to iterate over them. 412 */ 413 414/* 415 * Offset of the leaf/node space. First block in this space 416 * is the btree root. 417 */ 418#define XFS_DIR2_LEAF_SPACE 1 419#define XFS_DIR2_LEAF_OFFSET (XFS_DIR2_LEAF_SPACE * XFS_DIR2_SPACE_SIZE) 420 421/* 422 * Leaf block header. 423 */ 424typedef struct xfs_dir2_leaf_hdr { 425 xfs_da_blkinfo_t info; /* header for da routines */ 426 __be16 count; /* count of entries */ 427 __be16 stale; /* count of stale entries */ 428} xfs_dir2_leaf_hdr_t; 429 430struct xfs_dir3_leaf_hdr { 431 struct xfs_da3_blkinfo info; /* header for da routines */ 432 __be16 count; /* count of entries */ 433 __be16 stale; /* count of stale entries */ 434 __be32 pad; /* 64 bit alignment */ 435}; 436 437struct xfs_dir3_icleaf_hdr { 438 uint32_t forw; 439 uint32_t back; 440 uint16_t magic; 441 uint16_t count; 442 uint16_t stale; 443}; 444 445/* 446 * Leaf block entry. 447 */ 448typedef struct xfs_dir2_leaf_entry { 449 __be32 hashval; /* hash value of name */ 450 __be32 address; /* address of data entry */ 451} xfs_dir2_leaf_entry_t; 452 453/* 454 * Leaf block tail. 455 */ 456typedef struct xfs_dir2_leaf_tail { 457 __be32 bestcount; 458} xfs_dir2_leaf_tail_t; 459 460/* 461 * Leaf block. 462 */ 463typedef struct xfs_dir2_leaf { 464 xfs_dir2_leaf_hdr_t hdr; /* leaf header */ 465 xfs_dir2_leaf_entry_t __ents[]; /* entries */ 466} xfs_dir2_leaf_t; 467 468struct xfs_dir3_leaf { 469 struct xfs_dir3_leaf_hdr hdr; /* leaf header */ 470 struct xfs_dir2_leaf_entry __ents[]; /* entries */ 471}; 472 473#define XFS_DIR3_LEAF_CRC_OFF offsetof(struct xfs_dir3_leaf_hdr, info.crc) 474 475/* 476 * Get address of the bests array in the single-leaf block. 477 */ 478static inline __be16 * 479xfs_dir2_leaf_bests_p(struct xfs_dir2_leaf_tail *ltp) 480{ 481 return (__be16 *)ltp - be32_to_cpu(ltp->bestcount); 482} 483 484/* 485 * Free space block defintions for the node format. 486 */ 487 488/* 489 * Offset of the freespace index. 490 */ 491#define XFS_DIR2_FREE_SPACE 2 492#define XFS_DIR2_FREE_OFFSET (XFS_DIR2_FREE_SPACE * XFS_DIR2_SPACE_SIZE) 493 494typedef struct xfs_dir2_free_hdr { 495 __be32 magic; /* XFS_DIR2_FREE_MAGIC */ 496 __be32 firstdb; /* db of first entry */ 497 __be32 nvalid; /* count of valid entries */ 498 __be32 nused; /* count of used entries */ 499} xfs_dir2_free_hdr_t; 500 501typedef struct xfs_dir2_free { 502 xfs_dir2_free_hdr_t hdr; /* block header */ 503 __be16 bests[]; /* best free counts */ 504 /* unused entries are -1 */ 505} xfs_dir2_free_t; 506 507struct xfs_dir3_free_hdr { 508 struct xfs_dir3_blk_hdr hdr; 509 __be32 firstdb; /* db of first entry */ 510 __be32 nvalid; /* count of valid entries */ 511 __be32 nused; /* count of used entries */ 512 __be32 pad; /* 64 bit alignment */ 513}; 514 515struct xfs_dir3_free { 516 struct xfs_dir3_free_hdr hdr; 517 __be16 bests[]; /* best free counts */ 518 /* unused entries are -1 */ 519}; 520 521#define XFS_DIR3_FREE_CRC_OFF offsetof(struct xfs_dir3_free, hdr.hdr.crc) 522 523/* 524 * In core version of the free block header, abstracted away from on-disk format 525 * differences. Use this in the code, and convert to/from the disk version using 526 * xfs_dir3_free_hdr_from_disk/xfs_dir3_free_hdr_to_disk. 527 */ 528struct xfs_dir3_icfree_hdr { 529 uint32_t magic; 530 uint32_t firstdb; 531 uint32_t nvalid; 532 uint32_t nused; 533 534}; 535 536/* 537 * Single block format. 538 * 539 * The single block format looks like the following drawing on disk: 540 * 541 * +-------------------------------------------------+ 542 * | xfs_dir2_data_hdr_t | 543 * +-------------------------------------------------+ 544 * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | 545 * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t | 546 * | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t : 547 * | ... | 548 * +-------------------------------------------------+ 549 * | unused space | 550 * +-------------------------------------------------+ 551 * | ... | 552 * | xfs_dir2_leaf_entry_t | 553 * | xfs_dir2_leaf_entry_t | 554 * +-------------------------------------------------+ 555 * | xfs_dir2_block_tail_t | 556 * +-------------------------------------------------+ 557 * 558 * As all the entries are variable size structures the accessors below should 559 * be used to iterate over them. 560 */ 561 562typedef struct xfs_dir2_block_tail { 563 __be32 count; /* count of leaf entries */ 564 __be32 stale; /* count of stale lf entries */ 565} xfs_dir2_block_tail_t; 566 567/* 568 * Pointer to the leaf entries embedded in a data block (1-block format) 569 */ 570static inline struct xfs_dir2_leaf_entry * 571xfs_dir2_block_leaf_p(struct xfs_dir2_block_tail *btp) 572{ 573 return ((struct xfs_dir2_leaf_entry *)btp) - be32_to_cpu(btp->count); 574} 575 576 577/* 578 * Attribute storage layout 579 * 580 * Attribute lists are structured around Btrees where all the data 581 * elements are in the leaf nodes. Attribute names are hashed into an int, 582 * then that int is used as the index into the Btree. Since the hashval 583 * of an attribute name may not be unique, we may have duplicate keys. The 584 * internal links in the Btree are logical block offsets into the file. 585 * 586 * Struct leaf_entry's are packed from the top. Name/values grow from the 587 * bottom but are not packed. The freemap contains run-length-encoded entries 588 * for the free bytes after the leaf_entry's, but only the N largest such, 589 * smaller runs are dropped. When the freemap doesn't show enough space 590 * for an allocation, we compact the name/value area and try again. If we 591 * still don't have enough space, then we have to split the block. The 592 * name/value structs (both local and remote versions) must be 32bit aligned. 593 * 594 * Since we have duplicate hash keys, for each key that matches, compare 595 * the actual name string. The root and intermediate node search always 596 * takes the first-in-the-block key match found, so we should only have 597 * to work "forw"ard. If none matches, continue with the "forw"ard leaf 598 * nodes until the hash key changes or the attribute name is found. 599 * 600 * We store the fact that an attribute is a ROOT/USER/SECURE attribute in 601 * the leaf_entry. The namespaces are independent only because we also look 602 * at the namespace bit when we are looking for a matching attribute name. 603 * 604 * We also store an "incomplete" bit in the leaf_entry. It shows that an 605 * attribute is in the middle of being created and should not be shown to 606 * the user if we crash during the time that the bit is set. We clear the 607 * bit when we have finished setting up the attribute. We do this because 608 * we cannot create some large attributes inside a single transaction, and we 609 * need some indication that we weren't finished if we crash in the middle. 610 */ 611#define XFS_ATTR_LEAF_MAPSIZE 3 /* how many freespace slots */ 612 613/* 614 * Entries are packed toward the top as tight as possible. 615 */ 616typedef struct xfs_attr_shortform { 617 struct xfs_attr_sf_hdr { /* constant-structure header block */ 618 __be16 totsize; /* total bytes in shortform list */ 619 __u8 count; /* count of active entries */ 620 __u8 padding; 621 } hdr; 622 struct xfs_attr_sf_entry { 623 uint8_t namelen; /* actual length of name (no NULL) */ 624 uint8_t valuelen; /* actual length of value (no NULL) */ 625 uint8_t flags; /* flags bits (see xfs_attr_leaf.h) */ 626 uint8_t nameval[1]; /* name & value bytes concatenated */ 627 } list[1]; /* variable sized array */ 628} xfs_attr_shortform_t; 629 630typedef struct xfs_attr_leaf_map { /* RLE map of free bytes */ 631 __be16 base; /* base of free region */ 632 __be16 size; /* length of free region */ 633} xfs_attr_leaf_map_t; 634 635typedef struct xfs_attr_leaf_hdr { /* constant-structure header block */ 636 xfs_da_blkinfo_t info; /* block type, links, etc. */ 637 __be16 count; /* count of active leaf_entry's */ 638 __be16 usedbytes; /* num bytes of names/values stored */ 639 __be16 firstused; /* first used byte in name area */ 640 __u8 holes; /* != 0 if blk needs compaction */ 641 __u8 pad1; 642 xfs_attr_leaf_map_t freemap[XFS_ATTR_LEAF_MAPSIZE]; 643 /* N largest free regions */ 644} xfs_attr_leaf_hdr_t; 645 646typedef struct xfs_attr_leaf_entry { /* sorted on key, not name */ 647 __be32 hashval; /* hash value of name */ 648 __be16 nameidx; /* index into buffer of name/value */ 649 __u8 flags; /* LOCAL/ROOT/SECURE/INCOMPLETE flag */ 650 __u8 pad2; /* unused pad byte */ 651} xfs_attr_leaf_entry_t; 652 653typedef struct xfs_attr_leaf_name_local { 654 __be16 valuelen; /* number of bytes in value */ 655 __u8 namelen; /* length of name bytes */ 656 __u8 nameval[1]; /* name/value bytes */ 657} xfs_attr_leaf_name_local_t; 658 659typedef struct xfs_attr_leaf_name_remote { 660 __be32 valueblk; /* block number of value bytes */ 661 __be32 valuelen; /* number of bytes in value */ 662 __u8 namelen; /* length of name bytes */ 663 __u8 name[1]; /* name bytes */ 664} xfs_attr_leaf_name_remote_t; 665 666typedef struct xfs_attr_leafblock { 667 xfs_attr_leaf_hdr_t hdr; /* constant-structure header block */ 668 xfs_attr_leaf_entry_t entries[1]; /* sorted on key, not name */ 669 /* 670 * The rest of the block contains the following structures after the 671 * leaf entries, growing from the bottom up. The variables are never 672 * referenced and definining them can actually make gcc optimize away 673 * accesses to the 'entries' array above index 0 so don't do that. 674 * 675 * xfs_attr_leaf_name_local_t namelist; 676 * xfs_attr_leaf_name_remote_t valuelist; 677 */ 678} xfs_attr_leafblock_t; 679 680/* 681 * CRC enabled leaf structures. Called "version 3" structures to match the 682 * version number of the directory and dablk structures for this feature, and 683 * attr2 is already taken by the variable inode attribute fork size feature. 684 */ 685struct xfs_attr3_leaf_hdr { 686 struct xfs_da3_blkinfo info; 687 __be16 count; 688 __be16 usedbytes; 689 __be16 firstused; 690 __u8 holes; 691 __u8 pad1; 692 struct xfs_attr_leaf_map freemap[XFS_ATTR_LEAF_MAPSIZE]; 693 __be32 pad2; /* 64 bit alignment */ 694}; 695 696#define XFS_ATTR3_LEAF_CRC_OFF (offsetof(struct xfs_attr3_leaf_hdr, info.crc)) 697 698struct xfs_attr3_leafblock { 699 struct xfs_attr3_leaf_hdr hdr; 700 struct xfs_attr_leaf_entry entries[1]; 701 702 /* 703 * The rest of the block contains the following structures after the 704 * leaf entries, growing from the bottom up. The variables are never 705 * referenced, the locations accessed purely from helper functions. 706 * 707 * struct xfs_attr_leaf_name_local 708 * struct xfs_attr_leaf_name_remote 709 */ 710}; 711 712/* 713 * incore, neutral version of the attribute leaf header 714 */ 715struct xfs_attr3_icleaf_hdr { 716 uint32_t forw; 717 uint32_t back; 718 uint16_t magic; 719 uint16_t count; 720 uint16_t usedbytes; 721 /* 722 * firstused is 32-bit here instead of 16-bit like the on-disk variant 723 * to support maximum fsb size of 64k without overflow issues throughout 724 * the attr code. Instead, the overflow condition is handled on 725 * conversion to/from disk. 726 */ 727 uint32_t firstused; 728 __u8 holes; 729 struct { 730 uint16_t base; 731 uint16_t size; 732 } freemap[XFS_ATTR_LEAF_MAPSIZE]; 733}; 734 735/* 736 * Special value to represent fs block size in the leaf header firstused field. 737 * Only used when block size overflows the 2-bytes available on disk. 738 */ 739#define XFS_ATTR3_LEAF_NULLOFF 0 740 741/* 742 * Flags used in the leaf_entry[i].flags field. 743 * NOTE: the INCOMPLETE bit must not collide with the flags bits specified 744 * on the system call, they are "or"ed together for various operations. 745 */ 746#define XFS_ATTR_LOCAL_BIT 0 /* attr is stored locally */ 747#define XFS_ATTR_ROOT_BIT 1 /* limit access to trusted attrs */ 748#define XFS_ATTR_SECURE_BIT 2 /* limit access to secure attrs */ 749#define XFS_ATTR_INCOMPLETE_BIT 7 /* attr in middle of create/delete */ 750#define XFS_ATTR_LOCAL (1 << XFS_ATTR_LOCAL_BIT) 751#define XFS_ATTR_ROOT (1 << XFS_ATTR_ROOT_BIT) 752#define XFS_ATTR_SECURE (1 << XFS_ATTR_SECURE_BIT) 753#define XFS_ATTR_INCOMPLETE (1 << XFS_ATTR_INCOMPLETE_BIT) 754 755/* 756 * Conversion macros for converting namespace bits from argument flags 757 * to ondisk flags. 758 */ 759#define XFS_ATTR_NSP_ARGS_MASK (ATTR_ROOT | ATTR_SECURE) 760#define XFS_ATTR_NSP_ONDISK_MASK (XFS_ATTR_ROOT | XFS_ATTR_SECURE) 761#define XFS_ATTR_NSP_ONDISK(flags) ((flags) & XFS_ATTR_NSP_ONDISK_MASK) 762#define XFS_ATTR_NSP_ARGS(flags) ((flags) & XFS_ATTR_NSP_ARGS_MASK) 763#define XFS_ATTR_NSP_ARGS_TO_ONDISK(x) (((x) & ATTR_ROOT ? XFS_ATTR_ROOT : 0) |\ 764 ((x) & ATTR_SECURE ? XFS_ATTR_SECURE : 0)) 765#define XFS_ATTR_NSP_ONDISK_TO_ARGS(x) (((x) & XFS_ATTR_ROOT ? ATTR_ROOT : 0) |\ 766 ((x) & XFS_ATTR_SECURE ? ATTR_SECURE : 0)) 767 768/* 769 * Alignment for namelist and valuelist entries (since they are mixed 770 * there can be only one alignment value) 771 */ 772#define XFS_ATTR_LEAF_NAME_ALIGN ((uint)sizeof(xfs_dablk_t)) 773 774static inline int 775xfs_attr3_leaf_hdr_size(struct xfs_attr_leafblock *leafp) 776{ 777 if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) 778 return sizeof(struct xfs_attr3_leaf_hdr); 779 return sizeof(struct xfs_attr_leaf_hdr); 780} 781 782static inline struct xfs_attr_leaf_entry * 783xfs_attr3_leaf_entryp(xfs_attr_leafblock_t *leafp) 784{ 785 if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC)) 786 return &((struct xfs_attr3_leafblock *)leafp)->entries[0]; 787 return &leafp->entries[0]; 788} 789 790/* 791 * Cast typed pointers for "local" and "remote" name/value structs. 792 */ 793static inline char * 794xfs_attr3_leaf_name(xfs_attr_leafblock_t *leafp, int idx) 795{ 796 struct xfs_attr_leaf_entry *entries = xfs_attr3_leaf_entryp(leafp); 797 798 return &((char *)leafp)[be16_to_cpu(entries[idx].nameidx)]; 799} 800 801static inline xfs_attr_leaf_name_remote_t * 802xfs_attr3_leaf_name_remote(xfs_attr_leafblock_t *leafp, int idx) 803{ 804 return (xfs_attr_leaf_name_remote_t *)xfs_attr3_leaf_name(leafp, idx); 805} 806 807static inline xfs_attr_leaf_name_local_t * 808xfs_attr3_leaf_name_local(xfs_attr_leafblock_t *leafp, int idx) 809{ 810 return (xfs_attr_leaf_name_local_t *)xfs_attr3_leaf_name(leafp, idx); 811} 812 813/* 814 * Calculate total bytes used (including trailing pad for alignment) for 815 * a "local" name/value structure, a "remote" name/value structure, and 816 * a pointer which might be either. 817 */ 818static inline int xfs_attr_leaf_entsize_remote(int nlen) 819{ 820 return ((uint)sizeof(xfs_attr_leaf_name_remote_t) - 1 + (nlen) + \ 821 XFS_ATTR_LEAF_NAME_ALIGN - 1) & ~(XFS_ATTR_LEAF_NAME_ALIGN - 1); 822} 823 824static inline int xfs_attr_leaf_entsize_local(int nlen, int vlen) 825{ 826 return ((uint)sizeof(xfs_attr_leaf_name_local_t) - 1 + (nlen) + (vlen) + 827 XFS_ATTR_LEAF_NAME_ALIGN - 1) & ~(XFS_ATTR_LEAF_NAME_ALIGN - 1); 828} 829 830static inline int xfs_attr_leaf_entsize_local_max(int bsize) 831{ 832 return (((bsize) >> 1) + ((bsize) >> 2)); 833} 834 835 836 837/* 838 * Remote attribute block format definition 839 * 840 * There is one of these headers per filesystem block in a remote attribute. 841 * This is done to ensure there is a 1:1 mapping between the attribute value 842 * length and the number of blocks needed to store the attribute. This makes the 843 * verification of a buffer a little more complex, but greatly simplifies the 844 * allocation, reading and writing of these attributes as we don't have to guess 845 * the number of blocks needed to store the attribute data. 846 */ 847#define XFS_ATTR3_RMT_MAGIC 0x5841524d /* XARM */ 848 849struct xfs_attr3_rmt_hdr { 850 __be32 rm_magic; 851 __be32 rm_offset; 852 __be32 rm_bytes; 853 __be32 rm_crc; 854 uuid_t rm_uuid; 855 __be64 rm_owner; 856 __be64 rm_blkno; 857 __be64 rm_lsn; 858}; 859 860#define XFS_ATTR3_RMT_CRC_OFF offsetof(struct xfs_attr3_rmt_hdr, rm_crc) 861 862#define XFS_ATTR3_RMT_BUF_SPACE(mp, bufsize) \ 863 ((bufsize) - (xfs_sb_version_hascrc(&(mp)->m_sb) ? \ 864 sizeof(struct xfs_attr3_rmt_hdr) : 0)) 865 866/* Number of bytes in a directory block. */ 867static inline unsigned int xfs_dir2_dirblock_bytes(struct xfs_sb *sbp) 868{ 869 return 1 << (sbp->sb_blocklog + sbp->sb_dirblklog); 870} 871 872xfs_failaddr_t xfs_da3_blkinfo_verify(struct xfs_buf *bp, 873 struct xfs_da3_blkinfo *hdr3); 874 875#endif /* __XFS_DA_FORMAT_H__ */ 876