1/* 2 * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc. 3 * All Rights Reserved. 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU General Public License as 7 * published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it would be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 17 */ 18#ifndef __XFS_BTREE_H__ 19#define __XFS_BTREE_H__ 20 21struct xfs_buf; 22struct xfs_bmap_free; 23struct xfs_inode; 24struct xfs_mount; 25struct xfs_trans; 26 27/* 28 * This nonsense is to make -wlint happy. 29 */ 30#define XFS_LOOKUP_EQ ((xfs_lookup_t)XFS_LOOKUP_EQi) 31#define XFS_LOOKUP_LE ((xfs_lookup_t)XFS_LOOKUP_LEi) 32#define XFS_LOOKUP_GE ((xfs_lookup_t)XFS_LOOKUP_GEi) 33 34#define XFS_BTNUM_BNO ((xfs_btnum_t)XFS_BTNUM_BNOi) 35#define XFS_BTNUM_CNT ((xfs_btnum_t)XFS_BTNUM_CNTi) 36#define XFS_BTNUM_BMAP ((xfs_btnum_t)XFS_BTNUM_BMAPi) 37#define XFS_BTNUM_INO ((xfs_btnum_t)XFS_BTNUM_INOi) 38 39/* 40 * Short form header: space allocation btrees. 41 */ 42typedef struct xfs_btree_sblock { 43 __be32 bb_magic; /* magic number for block type */ 44 __be16 bb_level; /* 0 is a leaf */ 45 __be16 bb_numrecs; /* current # of data records */ 46 __be32 bb_leftsib; /* left sibling block or NULLAGBLOCK */ 47 __be32 bb_rightsib; /* right sibling block or NULLAGBLOCK */ 48} xfs_btree_sblock_t; 49 50/* 51 * Long form header: bmap btrees. 52 */ 53typedef struct xfs_btree_lblock { 54 __be32 bb_magic; /* magic number for block type */ 55 __be16 bb_level; /* 0 is a leaf */ 56 __be16 bb_numrecs; /* current # of data records */ 57 __be64 bb_leftsib; /* left sibling block or NULLDFSBNO */ 58 __be64 bb_rightsib; /* right sibling block or NULLDFSBNO */ 59} xfs_btree_lblock_t; 60 61/* 62 * Combined header and structure, used by common code. 63 */ 64typedef struct xfs_btree_hdr 65{ 66 __be32 bb_magic; /* magic number for block type */ 67 __be16 bb_level; /* 0 is a leaf */ 68 __be16 bb_numrecs; /* current # of data records */ 69} xfs_btree_hdr_t; 70 71typedef struct xfs_btree_block { 72 xfs_btree_hdr_t bb_h; /* header */ 73 union { 74 struct { 75 __be32 bb_leftsib; 76 __be32 bb_rightsib; 77 } s; /* short form pointers */ 78 struct { 79 __be64 bb_leftsib; 80 __be64 bb_rightsib; 81 } l; /* long form pointers */ 82 } bb_u; /* rest */ 83} xfs_btree_block_t; 84 85/* 86 * For logging record fields. 87 */ 88#define XFS_BB_MAGIC 0x01 89#define XFS_BB_LEVEL 0x02 90#define XFS_BB_NUMRECS 0x04 91#define XFS_BB_LEFTSIB 0x08 92#define XFS_BB_RIGHTSIB 0x10 93#define XFS_BB_NUM_BITS 5 94#define XFS_BB_ALL_BITS ((1 << XFS_BB_NUM_BITS) - 1) 95 96/* 97 * Boolean to select which form of xfs_btree_block_t.bb_u to use. 98 */ 99#define XFS_BTREE_LONG_PTRS(btnum) ((btnum) == XFS_BTNUM_BMAP) 100 101/* 102 * Magic numbers for btree blocks. 103 */ 104extern const __uint32_t xfs_magics[]; 105 106/* 107 * Maximum and minimum records in a btree block. 108 * Given block size, type prefix, and leaf flag (0 or 1). 109 * The divisor below is equivalent to lf ? (e1) : (e2) but that produces 110 * compiler warnings. 111 */ 112#define XFS_BTREE_BLOCK_MAXRECS(bsz,t,lf) \ 113 ((int)(((bsz) - (uint)sizeof(t ## _block_t)) / \ 114 (((lf) * (uint)sizeof(t ## _rec_t)) + \ 115 ((1 - (lf)) * \ 116 ((uint)sizeof(t ## _key_t) + (uint)sizeof(t ## _ptr_t)))))) 117#define XFS_BTREE_BLOCK_MINRECS(bsz,t,lf) \ 118 (XFS_BTREE_BLOCK_MAXRECS(bsz,t,lf) / 2) 119 120/* 121 * Record, key, and pointer address calculation macros. 122 * Given block size, type prefix, block pointer, and index of requested entry 123 * (first entry numbered 1). 124 */ 125#define XFS_BTREE_REC_ADDR(t,bb,i) \ 126 ((t ## _rec_t *)((char *)(bb) + sizeof(t ## _block_t) + \ 127 ((i) - 1) * sizeof(t ## _rec_t))) 128#define XFS_BTREE_KEY_ADDR(t,bb,i) \ 129 ((t ## _key_t *)((char *)(bb) + sizeof(t ## _block_t) + \ 130 ((i) - 1) * sizeof(t ## _key_t))) 131#define XFS_BTREE_PTR_ADDR(t,bb,i,mxr) \ 132 ((t ## _ptr_t *)((char *)(bb) + sizeof(t ## _block_t) + \ 133 (mxr) * sizeof(t ## _key_t) + ((i) - 1) * sizeof(t ## _ptr_t))) 134 135#define XFS_BTREE_MAXLEVELS 8 /* max of all btrees */ 136 137/* 138 * Btree cursor structure. 139 * This collects all information needed by the btree code in one place. 140 */ 141typedef struct xfs_btree_cur 142{ 143 struct xfs_trans *bc_tp; /* transaction we're in, if any */ 144 struct xfs_mount *bc_mp; /* file system mount struct */ 145 union { 146 xfs_alloc_rec_incore_t a; 147 xfs_bmbt_irec_t b; 148 xfs_inobt_rec_incore_t i; 149 } bc_rec; /* current insert/search record value */ 150 struct xfs_buf *bc_bufs[XFS_BTREE_MAXLEVELS]; /* buf ptr per level */ 151 int bc_ptrs[XFS_BTREE_MAXLEVELS]; /* key/record # */ 152 __uint8_t bc_ra[XFS_BTREE_MAXLEVELS]; /* readahead bits */ 153#define XFS_BTCUR_LEFTRA 1 /* left sibling has been read-ahead */ 154#define XFS_BTCUR_RIGHTRA 2 /* right sibling has been read-ahead */ 155 __uint8_t bc_nlevels; /* number of levels in the tree */ 156 __uint8_t bc_blocklog; /* log2(blocksize) of btree blocks */ 157 xfs_btnum_t bc_btnum; /* identifies which btree type */ 158 union { 159 struct { /* needed for BNO, CNT */ 160 struct xfs_buf *agbp; /* agf buffer pointer */ 161 xfs_agnumber_t agno; /* ag number */ 162 } a; 163 struct { /* needed for BMAP */ 164 struct xfs_inode *ip; /* pointer to our inode */ 165 struct xfs_bmap_free *flist; /* list to free after */ 166 xfs_fsblock_t firstblock; /* 1st blk allocated */ 167 int allocated; /* count of alloced */ 168 short forksize; /* fork's inode space */ 169 char whichfork; /* data or attr fork */ 170 char flags; /* flags */ 171#define XFS_BTCUR_BPRV_WASDEL 1 /* was delayed */ 172 } b; 173 struct { /* needed for INO */ 174 struct xfs_buf *agbp; /* agi buffer pointer */ 175 xfs_agnumber_t agno; /* ag number */ 176 } i; 177 } bc_private; /* per-btree type data */ 178} xfs_btree_cur_t; 179 180#define XFS_BTREE_NOERROR 0 181#define XFS_BTREE_ERROR 1 182 183/* 184 * Convert from buffer to btree block header. 185 */ 186#define XFS_BUF_TO_BLOCK(bp) ((xfs_btree_block_t *)XFS_BUF_PTR(bp)) 187#define XFS_BUF_TO_LBLOCK(bp) ((xfs_btree_lblock_t *)XFS_BUF_PTR(bp)) 188#define XFS_BUF_TO_SBLOCK(bp) ((xfs_btree_sblock_t *)XFS_BUF_PTR(bp)) 189 190 191#ifdef __KERNEL__ 192 193#ifdef DEBUG 194/* 195 * Debug routine: check that block header is ok. 196 */ 197void 198xfs_btree_check_block( 199 xfs_btree_cur_t *cur, /* btree cursor */ 200 xfs_btree_block_t *block, /* generic btree block pointer */ 201 int level, /* level of the btree block */ 202 struct xfs_buf *bp); /* buffer containing block, if any */ 203 204/* 205 * Debug routine: check that keys are in the right order. 206 */ 207void 208xfs_btree_check_key( 209 xfs_btnum_t btnum, /* btree identifier */ 210 void *ak1, /* pointer to left (lower) key */ 211 void *ak2); /* pointer to right (higher) key */ 212 213/* 214 * Debug routine: check that records are in the right order. 215 */ 216void 217xfs_btree_check_rec( 218 xfs_btnum_t btnum, /* btree identifier */ 219 void *ar1, /* pointer to left (lower) record */ 220 void *ar2); /* pointer to right (higher) record */ 221#else 222#define xfs_btree_check_block(a,b,c,d) 223#define xfs_btree_check_key(a,b,c) 224#define xfs_btree_check_rec(a,b,c) 225#endif /* DEBUG */ 226 227/* 228 * Checking routine: check that long form block header is ok. 229 */ 230int /* error (0 or EFSCORRUPTED) */ 231xfs_btree_check_lblock( 232 xfs_btree_cur_t *cur, /* btree cursor */ 233 xfs_btree_lblock_t *block, /* btree long form block pointer */ 234 int level, /* level of the btree block */ 235 struct xfs_buf *bp); /* buffer containing block, if any */ 236 237/* 238 * Checking routine: check that (long) pointer is ok. 239 */ 240int /* error (0 or EFSCORRUPTED) */ 241xfs_btree_check_lptr( 242 xfs_btree_cur_t *cur, /* btree cursor */ 243 xfs_dfsbno_t ptr, /* btree block disk address */ 244 int level); /* btree block level */ 245 246#define xfs_btree_check_lptr_disk(cur, ptr, level) \ 247 xfs_btree_check_lptr(cur, be64_to_cpu(ptr), level) 248 249/* 250 * Checking routine: check that short form block header is ok. 251 */ 252int /* error (0 or EFSCORRUPTED) */ 253xfs_btree_check_sblock( 254 xfs_btree_cur_t *cur, /* btree cursor */ 255 xfs_btree_sblock_t *block, /* btree short form block pointer */ 256 int level, /* level of the btree block */ 257 struct xfs_buf *bp); /* buffer containing block */ 258 259/* 260 * Checking routine: check that (short) pointer is ok. 261 */ 262int /* error (0 or EFSCORRUPTED) */ 263xfs_btree_check_sptr( 264 xfs_btree_cur_t *cur, /* btree cursor */ 265 xfs_agblock_t ptr, /* btree block disk address */ 266 int level); /* btree block level */ 267 268/* 269 * Delete the btree cursor. 270 */ 271void 272xfs_btree_del_cursor( 273 xfs_btree_cur_t *cur, /* btree cursor */ 274 int error); /* del because of error */ 275 276/* 277 * Duplicate the btree cursor. 278 * Allocate a new one, copy the record, re-get the buffers. 279 */ 280int /* error */ 281xfs_btree_dup_cursor( 282 xfs_btree_cur_t *cur, /* input cursor */ 283 xfs_btree_cur_t **ncur);/* output cursor */ 284 285/* 286 * Change the cursor to point to the first record in the current block 287 * at the given level. Other levels are unaffected. 288 */ 289int /* success=1, failure=0 */ 290xfs_btree_firstrec( 291 xfs_btree_cur_t *cur, /* btree cursor */ 292 int level); /* level to change */ 293 294/* 295 * Get a buffer for the block, return it with no data read. 296 * Long-form addressing. 297 */ 298struct xfs_buf * /* buffer for fsbno */ 299xfs_btree_get_bufl( 300 struct xfs_mount *mp, /* file system mount point */ 301 struct xfs_trans *tp, /* transaction pointer */ 302 xfs_fsblock_t fsbno, /* file system block number */ 303 uint lock); /* lock flags for get_buf */ 304 305/* 306 * Get a buffer for the block, return it with no data read. 307 * Short-form addressing. 308 */ 309struct xfs_buf * /* buffer for agno/agbno */ 310xfs_btree_get_bufs( 311 struct xfs_mount *mp, /* file system mount point */ 312 struct xfs_trans *tp, /* transaction pointer */ 313 xfs_agnumber_t agno, /* allocation group number */ 314 xfs_agblock_t agbno, /* allocation group block number */ 315 uint lock); /* lock flags for get_buf */ 316 317/* 318 * Allocate a new btree cursor. 319 * The cursor is either for allocation (A) or bmap (B). 320 */ 321xfs_btree_cur_t * /* new btree cursor */ 322xfs_btree_init_cursor( 323 struct xfs_mount *mp, /* file system mount point */ 324 struct xfs_trans *tp, /* transaction pointer */ 325 struct xfs_buf *agbp, /* (A only) buffer for agf structure */ 326 xfs_agnumber_t agno, /* (A only) allocation group number */ 327 xfs_btnum_t btnum, /* btree identifier */ 328 struct xfs_inode *ip, /* (B only) inode owning the btree */ 329 int whichfork); /* (B only) data/attr fork */ 330 331/* 332 * Check for the cursor referring to the last block at the given level. 333 */ 334int /* 1=is last block, 0=not last block */ 335xfs_btree_islastblock( 336 xfs_btree_cur_t *cur, /* btree cursor */ 337 int level); /* level to check */ 338 339/* 340 * Change the cursor to point to the last record in the current block 341 * at the given level. Other levels are unaffected. 342 */ 343int /* success=1, failure=0 */ 344xfs_btree_lastrec( 345 xfs_btree_cur_t *cur, /* btree cursor */ 346 int level); /* level to change */ 347 348/* 349 * Compute first and last byte offsets for the fields given. 350 * Interprets the offsets table, which contains struct field offsets. 351 */ 352void 353xfs_btree_offsets( 354 __int64_t fields, /* bitmask of fields */ 355 const short *offsets,/* table of field offsets */ 356 int nbits, /* number of bits to inspect */ 357 int *first, /* output: first byte offset */ 358 int *last); /* output: last byte offset */ 359 360/* 361 * Get a buffer for the block, return it read in. 362 * Long-form addressing. 363 */ 364int /* error */ 365xfs_btree_read_bufl( 366 struct xfs_mount *mp, /* file system mount point */ 367 struct xfs_trans *tp, /* transaction pointer */ 368 xfs_fsblock_t fsbno, /* file system block number */ 369 uint lock, /* lock flags for read_buf */ 370 struct xfs_buf **bpp, /* buffer for fsbno */ 371 int refval);/* ref count value for buffer */ 372 373/* 374 * Get a buffer for the block, return it read in. 375 * Short-form addressing. 376 */ 377int /* error */ 378xfs_btree_read_bufs( 379 struct xfs_mount *mp, /* file system mount point */ 380 struct xfs_trans *tp, /* transaction pointer */ 381 xfs_agnumber_t agno, /* allocation group number */ 382 xfs_agblock_t agbno, /* allocation group block number */ 383 uint lock, /* lock flags for read_buf */ 384 struct xfs_buf **bpp, /* buffer for agno/agbno */ 385 int refval);/* ref count value for buffer */ 386 387/* 388 * Read-ahead the block, don't wait for it, don't return a buffer. 389 * Long-form addressing. 390 */ 391void /* error */ 392xfs_btree_reada_bufl( 393 struct xfs_mount *mp, /* file system mount point */ 394 xfs_fsblock_t fsbno, /* file system block number */ 395 xfs_extlen_t count); /* count of filesystem blocks */ 396 397/* 398 * Read-ahead the block, don't wait for it, don't return a buffer. 399 * Short-form addressing. 400 */ 401void /* error */ 402xfs_btree_reada_bufs( 403 struct xfs_mount *mp, /* file system mount point */ 404 xfs_agnumber_t agno, /* allocation group number */ 405 xfs_agblock_t agbno, /* allocation group block number */ 406 xfs_extlen_t count); /* count of filesystem blocks */ 407 408/* 409 * Read-ahead btree blocks, at the given level. 410 * Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA. 411 */ 412int /* readahead block count */ 413xfs_btree_readahead_core( 414 xfs_btree_cur_t *cur, /* btree cursor */ 415 int lev, /* level in btree */ 416 int lr); /* left/right bits */ 417 418static inline int /* readahead block count */ 419xfs_btree_readahead( 420 xfs_btree_cur_t *cur, /* btree cursor */ 421 int lev, /* level in btree */ 422 int lr) /* left/right bits */ 423{ 424 if ((cur->bc_ra[lev] | lr) == cur->bc_ra[lev]) 425 return 0; 426 427 return xfs_btree_readahead_core(cur, lev, lr); 428} 429 430 431/* 432 * Set the buffer for level "lev" in the cursor to bp, releasing 433 * any previous buffer. 434 */ 435void 436xfs_btree_setbuf( 437 xfs_btree_cur_t *cur, /* btree cursor */ 438 int lev, /* level in btree */ 439 struct xfs_buf *bp); /* new buffer to set */ 440 441#endif /* __KERNEL__ */ 442 443 444/* 445 * Min and max functions for extlen, agblock, fileoff, and filblks types. 446 */ 447#define XFS_EXTLEN_MIN(a,b) \ 448 ((xfs_extlen_t)(a) < (xfs_extlen_t)(b) ? \ 449 (xfs_extlen_t)(a) : (xfs_extlen_t)(b)) 450#define XFS_EXTLEN_MAX(a,b) \ 451 ((xfs_extlen_t)(a) > (xfs_extlen_t)(b) ? \ 452 (xfs_extlen_t)(a) : (xfs_extlen_t)(b)) 453#define XFS_AGBLOCK_MIN(a,b) \ 454 ((xfs_agblock_t)(a) < (xfs_agblock_t)(b) ? \ 455 (xfs_agblock_t)(a) : (xfs_agblock_t)(b)) 456#define XFS_AGBLOCK_MAX(a,b) \ 457 ((xfs_agblock_t)(a) > (xfs_agblock_t)(b) ? \ 458 (xfs_agblock_t)(a) : (xfs_agblock_t)(b)) 459#define XFS_FILEOFF_MIN(a,b) \ 460 ((xfs_fileoff_t)(a) < (xfs_fileoff_t)(b) ? \ 461 (xfs_fileoff_t)(a) : (xfs_fileoff_t)(b)) 462#define XFS_FILEOFF_MAX(a,b) \ 463 ((xfs_fileoff_t)(a) > (xfs_fileoff_t)(b) ? \ 464 (xfs_fileoff_t)(a) : (xfs_fileoff_t)(b)) 465#define XFS_FILBLKS_MIN(a,b) \ 466 ((xfs_filblks_t)(a) < (xfs_filblks_t)(b) ? \ 467 (xfs_filblks_t)(a) : (xfs_filblks_t)(b)) 468#define XFS_FILBLKS_MAX(a,b) \ 469 ((xfs_filblks_t)(a) > (xfs_filblks_t)(b) ? \ 470 (xfs_filblks_t)(a) : (xfs_filblks_t)(b)) 471 472#define XFS_FSB_SANITY_CHECK(mp,fsb) \ 473 (XFS_FSB_TO_AGNO(mp, fsb) < mp->m_sb.sb_agcount && \ 474 XFS_FSB_TO_AGBNO(mp, fsb) < mp->m_sb.sb_agblocks) 475 476#endif /* __XFS_BTREE_H__ */ 477