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 27extern kmem_zone_t *xfs_btree_cur_zone; 28 29/* 30 * This nonsense is to make -wlint happy. 31 */ 32#define XFS_LOOKUP_EQ ((xfs_lookup_t)XFS_LOOKUP_EQi) 33#define XFS_LOOKUP_LE ((xfs_lookup_t)XFS_LOOKUP_LEi) 34#define XFS_LOOKUP_GE ((xfs_lookup_t)XFS_LOOKUP_GEi) 35 36#define XFS_BTNUM_BNO ((xfs_btnum_t)XFS_BTNUM_BNOi) 37#define XFS_BTNUM_CNT ((xfs_btnum_t)XFS_BTNUM_CNTi) 38#define XFS_BTNUM_BMAP ((xfs_btnum_t)XFS_BTNUM_BMAPi) 39#define XFS_BTNUM_INO ((xfs_btnum_t)XFS_BTNUM_INOi) 40 41/* 42 * Generic btree header. 43 * 44 * This is a combination of the actual format used on disk for short and long 45 * format btrees. The first three fields are shared by both format, but 46 * the pointers are different and should be used with care. 47 * 48 * To get the size of the actual short or long form headers please use 49 * the size macros below. Never use sizeof(xfs_btree_block). 50 */ 51struct xfs_btree_block { 52 __be32 bb_magic; /* magic number for block type */ 53 __be16 bb_level; /* 0 is a leaf */ 54 __be16 bb_numrecs; /* current # of data records */ 55 union { 56 struct { 57 __be32 bb_leftsib; 58 __be32 bb_rightsib; 59 } s; /* short form pointers */ 60 struct { 61 __be64 bb_leftsib; 62 __be64 bb_rightsib; 63 } l; /* long form pointers */ 64 } bb_u; /* rest */ 65}; 66 67#define XFS_BTREE_SBLOCK_LEN 16 /* size of a short form block */ 68#define XFS_BTREE_LBLOCK_LEN 24 /* size of a long form block */ 69 70 71/* 72 * Generic key, ptr and record wrapper structures. 73 * 74 * These are disk format structures, and are converted where necessary 75 * by the btree specific code that needs to interpret them. 76 */ 77union xfs_btree_ptr { 78 __be32 s; /* short form ptr */ 79 __be64 l; /* long form ptr */ 80}; 81 82union xfs_btree_key { 83 xfs_bmbt_key_t bmbt; 84 xfs_bmdr_key_t bmbr; /* bmbt root block */ 85 xfs_alloc_key_t alloc; 86 xfs_inobt_key_t inobt; 87}; 88 89union xfs_btree_rec { 90 xfs_bmbt_rec_t bmbt; 91 xfs_bmdr_rec_t bmbr; /* bmbt root block */ 92 xfs_alloc_rec_t alloc; 93 xfs_inobt_rec_t inobt; 94}; 95 96/* 97 * For logging record fields. 98 */ 99#define XFS_BB_MAGIC 0x01 100#define XFS_BB_LEVEL 0x02 101#define XFS_BB_NUMRECS 0x04 102#define XFS_BB_LEFTSIB 0x08 103#define XFS_BB_RIGHTSIB 0x10 104#define XFS_BB_NUM_BITS 5 105#define XFS_BB_ALL_BITS ((1 << XFS_BB_NUM_BITS) - 1) 106 107/* 108 * Magic numbers for btree blocks. 109 */ 110extern const __uint32_t xfs_magics[]; 111 112/* 113 * Generic stats interface 114 */ 115#define __XFS_BTREE_STATS_INC(type, stat) \ 116 XFS_STATS_INC(xs_ ## type ## _2_ ## stat) 117#define XFS_BTREE_STATS_INC(cur, stat) \ 118do { \ 119 switch (cur->bc_btnum) { \ 120 case XFS_BTNUM_BNO: __XFS_BTREE_STATS_INC(abtb, stat); break; \ 121 case XFS_BTNUM_CNT: __XFS_BTREE_STATS_INC(abtc, stat); break; \ 122 case XFS_BTNUM_BMAP: __XFS_BTREE_STATS_INC(bmbt, stat); break; \ 123 case XFS_BTNUM_INO: __XFS_BTREE_STATS_INC(ibt, stat); break; \ 124 case XFS_BTNUM_MAX: ASSERT(0); /* fucking gcc */ ; break; \ 125 } \ 126} while (0) 127 128#define __XFS_BTREE_STATS_ADD(type, stat, val) \ 129 XFS_STATS_ADD(xs_ ## type ## _2_ ## stat, val) 130#define XFS_BTREE_STATS_ADD(cur, stat, val) \ 131do { \ 132 switch (cur->bc_btnum) { \ 133 case XFS_BTNUM_BNO: __XFS_BTREE_STATS_ADD(abtb, stat, val); break; \ 134 case XFS_BTNUM_CNT: __XFS_BTREE_STATS_ADD(abtc, stat, val); break; \ 135 case XFS_BTNUM_BMAP: __XFS_BTREE_STATS_ADD(bmbt, stat, val); break; \ 136 case XFS_BTNUM_INO: __XFS_BTREE_STATS_ADD(ibt, stat, val); break; \ 137 case XFS_BTNUM_MAX: ASSERT(0); /* fucking gcc */ ; break; \ 138 } \ 139} while (0) 140 141#define XFS_BTREE_MAXLEVELS 8 /* max of all btrees */ 142 143struct xfs_btree_ops { 144 /* size of the key and record structures */ 145 size_t key_len; 146 size_t rec_len; 147 148 /* cursor operations */ 149 struct xfs_btree_cur *(*dup_cursor)(struct xfs_btree_cur *); 150 void (*update_cursor)(struct xfs_btree_cur *src, 151 struct xfs_btree_cur *dst); 152 153 /* update btree root pointer */ 154 void (*set_root)(struct xfs_btree_cur *cur, 155 union xfs_btree_ptr *nptr, int level_change); 156 int (*kill_root)(struct xfs_btree_cur *cur, struct xfs_buf *bp, 157 int level, union xfs_btree_ptr *newroot); 158 159 /* block allocation / freeing */ 160 int (*alloc_block)(struct xfs_btree_cur *cur, 161 union xfs_btree_ptr *start_bno, 162 union xfs_btree_ptr *new_bno, 163 int length, int *stat); 164 int (*free_block)(struct xfs_btree_cur *cur, struct xfs_buf *bp); 165 166 /* update last record information */ 167 void (*update_lastrec)(struct xfs_btree_cur *cur, 168 struct xfs_btree_block *block, 169 union xfs_btree_rec *rec, 170 int ptr, int reason); 171 172 /* records in block/level */ 173 int (*get_minrecs)(struct xfs_btree_cur *cur, int level); 174 int (*get_maxrecs)(struct xfs_btree_cur *cur, int level); 175 176 /* records on disk. Matter for the root in inode case. */ 177 int (*get_dmaxrecs)(struct xfs_btree_cur *cur, int level); 178 179 /* init values of btree structures */ 180 void (*init_key_from_rec)(union xfs_btree_key *key, 181 union xfs_btree_rec *rec); 182 void (*init_rec_from_key)(union xfs_btree_key *key, 183 union xfs_btree_rec *rec); 184 void (*init_rec_from_cur)(struct xfs_btree_cur *cur, 185 union xfs_btree_rec *rec); 186 void (*init_ptr_from_cur)(struct xfs_btree_cur *cur, 187 union xfs_btree_ptr *ptr); 188 189 /* difference between key value and cursor value */ 190 __int64_t (*key_diff)(struct xfs_btree_cur *cur, 191 union xfs_btree_key *key); 192 193#ifdef DEBUG 194 /* check that k1 is lower than k2 */ 195 int (*keys_inorder)(struct xfs_btree_cur *cur, 196 union xfs_btree_key *k1, 197 union xfs_btree_key *k2); 198 199 /* check that r1 is lower than r2 */ 200 int (*recs_inorder)(struct xfs_btree_cur *cur, 201 union xfs_btree_rec *r1, 202 union xfs_btree_rec *r2); 203#endif 204 205 /* btree tracing */ 206#ifdef XFS_BTREE_TRACE 207 void (*trace_enter)(struct xfs_btree_cur *, const char *, 208 char *, int, int, __psunsigned_t, 209 __psunsigned_t, __psunsigned_t, 210 __psunsigned_t, __psunsigned_t, 211 __psunsigned_t, __psunsigned_t, 212 __psunsigned_t, __psunsigned_t, 213 __psunsigned_t, __psunsigned_t); 214 void (*trace_cursor)(struct xfs_btree_cur *, __uint32_t *, 215 __uint64_t *, __uint64_t *); 216 void (*trace_key)(struct xfs_btree_cur *, 217 union xfs_btree_key *, __uint64_t *, 218 __uint64_t *); 219 void (*trace_record)(struct xfs_btree_cur *, 220 union xfs_btree_rec *, __uint64_t *, 221 __uint64_t *, __uint64_t *); 222#endif 223}; 224 225/* 226 * Reasons for the update_lastrec method to be called. 227 */ 228#define LASTREC_UPDATE 0 229#define LASTREC_INSREC 1 230#define LASTREC_DELREC 2 231 232 233/* 234 * Btree cursor structure. 235 * This collects all information needed by the btree code in one place. 236 */ 237typedef struct xfs_btree_cur 238{ 239 struct xfs_trans *bc_tp; /* transaction we're in, if any */ 240 struct xfs_mount *bc_mp; /* file system mount struct */ 241 const struct xfs_btree_ops *bc_ops; 242 uint bc_flags; /* btree features - below */ 243 union { 244 xfs_alloc_rec_incore_t a; 245 xfs_bmbt_irec_t b; 246 xfs_inobt_rec_incore_t i; 247 } bc_rec; /* current insert/search record value */ 248 struct xfs_buf *bc_bufs[XFS_BTREE_MAXLEVELS]; /* buf ptr per level */ 249 int bc_ptrs[XFS_BTREE_MAXLEVELS]; /* key/record # */ 250 __uint8_t bc_ra[XFS_BTREE_MAXLEVELS]; /* readahead bits */ 251#define XFS_BTCUR_LEFTRA 1 /* left sibling has been read-ahead */ 252#define XFS_BTCUR_RIGHTRA 2 /* right sibling has been read-ahead */ 253 __uint8_t bc_nlevels; /* number of levels in the tree */ 254 __uint8_t bc_blocklog; /* log2(blocksize) of btree blocks */ 255 xfs_btnum_t bc_btnum; /* identifies which btree type */ 256 union { 257 struct { /* needed for BNO, CNT, INO */ 258 struct xfs_buf *agbp; /* agf/agi buffer pointer */ 259 xfs_agnumber_t agno; /* ag number */ 260 } a; 261 struct { /* needed for BMAP */ 262 struct xfs_inode *ip; /* pointer to our inode */ 263 struct xfs_bmap_free *flist; /* list to free after */ 264 xfs_fsblock_t firstblock; /* 1st blk allocated */ 265 int allocated; /* count of alloced */ 266 short forksize; /* fork's inode space */ 267 char whichfork; /* data or attr fork */ 268 char flags; /* flags */ 269#define XFS_BTCUR_BPRV_WASDEL 1 /* was delayed */ 270 } b; 271 } bc_private; /* per-btree type data */ 272} xfs_btree_cur_t; 273 274/* cursor flags */ 275#define XFS_BTREE_LONG_PTRS (1<<0) /* pointers are 64bits long */ 276#define XFS_BTREE_ROOT_IN_INODE (1<<1) /* root may be variable size */ 277#define XFS_BTREE_LASTREC_UPDATE (1<<2) /* track last rec externally */ 278 279 280#define XFS_BTREE_NOERROR 0 281#define XFS_BTREE_ERROR 1 282 283/* 284 * Convert from buffer to btree block header. 285 */ 286#define XFS_BUF_TO_BLOCK(bp) ((struct xfs_btree_block *)XFS_BUF_PTR(bp)) 287 288 289/* 290 * Check that block header is ok. 291 */ 292int 293xfs_btree_check_block( 294 struct xfs_btree_cur *cur, /* btree cursor */ 295 struct xfs_btree_block *block, /* generic btree block pointer */ 296 int level, /* level of the btree block */ 297 struct xfs_buf *bp); /* buffer containing block, if any */ 298 299/* 300 * Check that (long) pointer is ok. 301 */ 302int /* error (0 or EFSCORRUPTED) */ 303xfs_btree_check_lptr( 304 struct xfs_btree_cur *cur, /* btree cursor */ 305 xfs_dfsbno_t ptr, /* btree block disk address */ 306 int level); /* btree block level */ 307 308/* 309 * Delete the btree cursor. 310 */ 311void 312xfs_btree_del_cursor( 313 xfs_btree_cur_t *cur, /* btree cursor */ 314 int error); /* del because of error */ 315 316/* 317 * Duplicate the btree cursor. 318 * Allocate a new one, copy the record, re-get the buffers. 319 */ 320int /* error */ 321xfs_btree_dup_cursor( 322 xfs_btree_cur_t *cur, /* input cursor */ 323 xfs_btree_cur_t **ncur);/* output cursor */ 324 325/* 326 * Get a buffer for the block, return it with no data read. 327 * Long-form addressing. 328 */ 329struct xfs_buf * /* buffer for fsbno */ 330xfs_btree_get_bufl( 331 struct xfs_mount *mp, /* file system mount point */ 332 struct xfs_trans *tp, /* transaction pointer */ 333 xfs_fsblock_t fsbno, /* file system block number */ 334 uint lock); /* lock flags for get_buf */ 335 336/* 337 * Get a buffer for the block, return it with no data read. 338 * Short-form addressing. 339 */ 340struct xfs_buf * /* buffer for agno/agbno */ 341xfs_btree_get_bufs( 342 struct xfs_mount *mp, /* file system mount point */ 343 struct xfs_trans *tp, /* transaction pointer */ 344 xfs_agnumber_t agno, /* allocation group number */ 345 xfs_agblock_t agbno, /* allocation group block number */ 346 uint lock); /* lock flags for get_buf */ 347 348/* 349 * Check for the cursor referring to the last block at the given level. 350 */ 351int /* 1=is last block, 0=not last block */ 352xfs_btree_islastblock( 353 xfs_btree_cur_t *cur, /* btree cursor */ 354 int level); /* level to check */ 355 356/* 357 * Compute first and last byte offsets for the fields given. 358 * Interprets the offsets table, which contains struct field offsets. 359 */ 360void 361xfs_btree_offsets( 362 __int64_t fields, /* bitmask of fields */ 363 const short *offsets,/* table of field offsets */ 364 int nbits, /* number of bits to inspect */ 365 int *first, /* output: first byte offset */ 366 int *last); /* output: last byte offset */ 367 368/* 369 * Get a buffer for the block, return it read in. 370 * Long-form addressing. 371 */ 372int /* error */ 373xfs_btree_read_bufl( 374 struct xfs_mount *mp, /* file system mount point */ 375 struct xfs_trans *tp, /* transaction pointer */ 376 xfs_fsblock_t fsbno, /* file system block number */ 377 uint lock, /* lock flags for read_buf */ 378 struct xfs_buf **bpp, /* buffer for fsbno */ 379 int refval);/* ref count value for buffer */ 380 381/* 382 * Read-ahead the block, don't wait for it, don't return a buffer. 383 * Long-form addressing. 384 */ 385void /* error */ 386xfs_btree_reada_bufl( 387 struct xfs_mount *mp, /* file system mount point */ 388 xfs_fsblock_t fsbno, /* file system block number */ 389 xfs_extlen_t count); /* count of filesystem blocks */ 390 391/* 392 * Read-ahead the block, don't wait for it, don't return a buffer. 393 * Short-form addressing. 394 */ 395void /* error */ 396xfs_btree_reada_bufs( 397 struct xfs_mount *mp, /* file system mount point */ 398 xfs_agnumber_t agno, /* allocation group number */ 399 xfs_agblock_t agbno, /* allocation group block number */ 400 xfs_extlen_t count); /* count of filesystem blocks */ 401 402/* 403 * Set the buffer for level "lev" in the cursor to bp, releasing 404 * any previous buffer. 405 */ 406void 407xfs_btree_setbuf( 408 xfs_btree_cur_t *cur, /* btree cursor */ 409 int lev, /* level in btree */ 410 struct xfs_buf *bp); /* new buffer to set */ 411 412 413/* 414 * Common btree core entry points. 415 */ 416int xfs_btree_increment(struct xfs_btree_cur *, int, int *); 417int xfs_btree_decrement(struct xfs_btree_cur *, int, int *); 418int xfs_btree_lookup(struct xfs_btree_cur *, xfs_lookup_t, int *); 419int xfs_btree_update(struct xfs_btree_cur *, union xfs_btree_rec *); 420int xfs_btree_new_iroot(struct xfs_btree_cur *, int *, int *); 421int xfs_btree_insert(struct xfs_btree_cur *, int *); 422int xfs_btree_delete(struct xfs_btree_cur *, int *); 423int xfs_btree_get_rec(struct xfs_btree_cur *, union xfs_btree_rec **, int *); 424 425/* 426 * Internal btree helpers also used by xfs_bmap.c. 427 */ 428void xfs_btree_log_block(struct xfs_btree_cur *, struct xfs_buf *, int); 429void xfs_btree_log_recs(struct xfs_btree_cur *, struct xfs_buf *, int, int); 430 431/* 432 * Helpers. 433 */ 434static inline int xfs_btree_get_numrecs(struct xfs_btree_block *block) 435{ 436 return be16_to_cpu(block->bb_numrecs); 437} 438 439static inline void xfs_btree_set_numrecs(struct xfs_btree_block *block, 440 __uint16_t numrecs) 441{ 442 block->bb_numrecs = cpu_to_be16(numrecs); 443} 444 445static inline int xfs_btree_get_level(struct xfs_btree_block *block) 446{ 447 return be16_to_cpu(block->bb_level); 448} 449 450 451/* 452 * Min and max functions for extlen, agblock, fileoff, and filblks types. 453 */ 454#define XFS_EXTLEN_MIN(a,b) min_t(xfs_extlen_t, (a), (b)) 455#define XFS_EXTLEN_MAX(a,b) max_t(xfs_extlen_t, (a), (b)) 456#define XFS_AGBLOCK_MIN(a,b) min_t(xfs_agblock_t, (a), (b)) 457#define XFS_AGBLOCK_MAX(a,b) max_t(xfs_agblock_t, (a), (b)) 458#define XFS_FILEOFF_MIN(a,b) min_t(xfs_fileoff_t, (a), (b)) 459#define XFS_FILEOFF_MAX(a,b) max_t(xfs_fileoff_t, (a), (b)) 460#define XFS_FILBLKS_MIN(a,b) min_t(xfs_filblks_t, (a), (b)) 461#define XFS_FILBLKS_MAX(a,b) max_t(xfs_filblks_t, (a), (b)) 462 463#define XFS_FSB_SANITY_CHECK(mp,fsb) \ 464 (XFS_FSB_TO_AGNO(mp, fsb) < mp->m_sb.sb_agcount && \ 465 XFS_FSB_TO_AGBNO(mp, fsb) < mp->m_sb.sb_agblocks) 466 467#endif /* __XFS_BTREE_H__ */ 468