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
21 struct xfs_buf;
22 struct xfs_bmap_free;
23 struct xfs_inode;
24 struct xfs_mount;
25 struct xfs_trans;
26
27 extern 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 the
46 * 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 the size
49 * macros below. Never use sizeof(xfs_btree_block).
50 *
51 * The blkno, crc, lsn, owner and uuid fields are only available in filesystems
52 * with the crc feature bit, and all accesses to them must be conditional on
53 * that flag.
54 */
55 struct xfs_btree_block {
56 __be32 bb_magic; /* magic number for block type */
57 __be16 bb_level; /* 0 is a leaf */
58 __be16 bb_numrecs; /* current # of data records */
59 union {
60 struct {
61 __be32 bb_leftsib;
62 __be32 bb_rightsib;
63
64 __be64 bb_blkno;
65 __be64 bb_lsn;
66 uuid_t bb_uuid;
67 __be32 bb_owner;
68 __le32 bb_crc;
69 } s; /* short form pointers */
70 struct {
71 __be64 bb_leftsib;
72 __be64 bb_rightsib;
73
74 __be64 bb_blkno;
75 __be64 bb_lsn;
76 uuid_t bb_uuid;
77 __be64 bb_owner;
78 __le32 bb_crc;
79 __be32 bb_pad; /* padding for alignment */
80 } l; /* long form pointers */
81 } bb_u; /* rest */
82 };
83
84 #define XFS_BTREE_SBLOCK_LEN 16 /* size of a short form block */
85 #define XFS_BTREE_LBLOCK_LEN 24 /* size of a long form block */
86
87 /* sizes of CRC enabled btree blocks */
88 #define XFS_BTREE_SBLOCK_CRC_LEN (XFS_BTREE_SBLOCK_LEN + 40)
89 #define XFS_BTREE_LBLOCK_CRC_LEN (XFS_BTREE_LBLOCK_LEN + 48)
90
91
92 #define XFS_BTREE_SBLOCK_CRC_OFF \
93 offsetof(struct xfs_btree_block, bb_u.s.bb_crc)
94 #define XFS_BTREE_LBLOCK_CRC_OFF \
95 offsetof(struct xfs_btree_block, bb_u.l.bb_crc)
96
97
98 /*
99 * Generic key, ptr and record wrapper structures.
100 *
101 * These are disk format structures, and are converted where necessary
102 * by the btree specific code that needs to interpret them.
103 */
104 union xfs_btree_ptr {
105 __be32 s; /* short form ptr */
106 __be64 l; /* long form ptr */
107 };
108
109 union xfs_btree_key {
110 xfs_bmbt_key_t bmbt;
111 xfs_bmdr_key_t bmbr; /* bmbt root block */
112 xfs_alloc_key_t alloc;
113 xfs_inobt_key_t inobt;
114 };
115
116 union xfs_btree_rec {
117 xfs_bmbt_rec_t bmbt;
118 xfs_bmdr_rec_t bmbr; /* bmbt root block */
119 xfs_alloc_rec_t alloc;
120 xfs_inobt_rec_t inobt;
121 };
122
123 /*
124 * For logging record fields.
125 */
126 #define XFS_BB_MAGIC 0x01
127 #define XFS_BB_LEVEL 0x02
128 #define XFS_BB_NUMRECS 0x04
129 #define XFS_BB_LEFTSIB 0x08
130 #define XFS_BB_RIGHTSIB 0x10
131 #define XFS_BB_BLKNO 0x20
132 #define XFS_BB_NUM_BITS 5
133 #define XFS_BB_ALL_BITS ((1 << XFS_BB_NUM_BITS) - 1)
134 #define XFS_BB_NUM_BITS_CRC 8
135 #define XFS_BB_ALL_BITS_CRC ((1 << XFS_BB_NUM_BITS_CRC) - 1)
136
137 /*
138 * Generic stats interface
139 */
140 #define __XFS_BTREE_STATS_INC(type, stat) \
141 XFS_STATS_INC(xs_ ## type ## _2_ ## stat)
142 #define XFS_BTREE_STATS_INC(cur, stat) \
143 do { \
144 switch (cur->bc_btnum) { \
145 case XFS_BTNUM_BNO: __XFS_BTREE_STATS_INC(abtb, stat); break; \
146 case XFS_BTNUM_CNT: __XFS_BTREE_STATS_INC(abtc, stat); break; \
147 case XFS_BTNUM_BMAP: __XFS_BTREE_STATS_INC(bmbt, stat); break; \
148 case XFS_BTNUM_INO: __XFS_BTREE_STATS_INC(ibt, stat); break; \
149 case XFS_BTNUM_MAX: ASSERT(0); /* fucking gcc */ ; break; \
150 } \
151 } while (0)
152
153 #define __XFS_BTREE_STATS_ADD(type, stat, val) \
154 XFS_STATS_ADD(xs_ ## type ## _2_ ## stat, val)
155 #define XFS_BTREE_STATS_ADD(cur, stat, val) \
156 do { \
157 switch (cur->bc_btnum) { \
158 case XFS_BTNUM_BNO: __XFS_BTREE_STATS_ADD(abtb, stat, val); break; \
159 case XFS_BTNUM_CNT: __XFS_BTREE_STATS_ADD(abtc, stat, val); break; \
160 case XFS_BTNUM_BMAP: __XFS_BTREE_STATS_ADD(bmbt, stat, val); break; \
161 case XFS_BTNUM_INO: __XFS_BTREE_STATS_ADD(ibt, stat, val); break; \
162 case XFS_BTNUM_MAX: ASSERT(0); /* fucking gcc */ ; break; \
163 } \
164 } while (0)
165
166 #define XFS_BTREE_MAXLEVELS 8 /* max of all btrees */
167
168 struct xfs_btree_ops {
169 /* size of the key and record structures */
170 size_t key_len;
171 size_t rec_len;
172
173 /* cursor operations */
174 struct xfs_btree_cur *(*dup_cursor)(struct xfs_btree_cur *);
175 void (*update_cursor)(struct xfs_btree_cur *src,
176 struct xfs_btree_cur *dst);
177
178 /* update btree root pointer */
179 void (*set_root)(struct xfs_btree_cur *cur,
180 union xfs_btree_ptr *nptr, int level_change);
181
182 /* block allocation / freeing */
183 int (*alloc_block)(struct xfs_btree_cur *cur,
184 union xfs_btree_ptr *start_bno,
185 union xfs_btree_ptr *new_bno,
186 int length, int *stat);
187 int (*free_block)(struct xfs_btree_cur *cur, struct xfs_buf *bp);
188
189 /* update last record information */
190 void (*update_lastrec)(struct xfs_btree_cur *cur,
191 struct xfs_btree_block *block,
192 union xfs_btree_rec *rec,
193 int ptr, int reason);
194
195 /* records in block/level */
196 int (*get_minrecs)(struct xfs_btree_cur *cur, int level);
197 int (*get_maxrecs)(struct xfs_btree_cur *cur, int level);
198
199 /* records on disk. Matter for the root in inode case. */
200 int (*get_dmaxrecs)(struct xfs_btree_cur *cur, int level);
201
202 /* init values of btree structures */
203 void (*init_key_from_rec)(union xfs_btree_key *key,
204 union xfs_btree_rec *rec);
205 void (*init_rec_from_key)(union xfs_btree_key *key,
206 union xfs_btree_rec *rec);
207 void (*init_rec_from_cur)(struct xfs_btree_cur *cur,
208 union xfs_btree_rec *rec);
209 void (*init_ptr_from_cur)(struct xfs_btree_cur *cur,
210 union xfs_btree_ptr *ptr);
211
212 /* difference between key value and cursor value */
213 __int64_t (*key_diff)(struct xfs_btree_cur *cur,
214 union xfs_btree_key *key);
215
216 const struct xfs_buf_ops *buf_ops;
217
218 #if defined(DEBUG) || defined(XFS_WARN)
219 /* check that k1 is lower than k2 */
220 int (*keys_inorder)(struct xfs_btree_cur *cur,
221 union xfs_btree_key *k1,
222 union xfs_btree_key *k2);
223
224 /* check that r1 is lower than r2 */
225 int (*recs_inorder)(struct xfs_btree_cur *cur,
226 union xfs_btree_rec *r1,
227 union xfs_btree_rec *r2);
228 #endif
229 };
230
231 /*
232 * Reasons for the update_lastrec method to be called.
233 */
234 #define LASTREC_UPDATE 0
235 #define LASTREC_INSREC 1
236 #define LASTREC_DELREC 2
237
238
239 /*
240 * Btree cursor structure.
241 * This collects all information needed by the btree code in one place.
242 */
243 typedef struct xfs_btree_cur
244 {
245 struct xfs_trans *bc_tp; /* transaction we're in, if any */
246 struct xfs_mount *bc_mp; /* file system mount struct */
247 const struct xfs_btree_ops *bc_ops;
248 uint bc_flags; /* btree features - below */
249 union {
250 xfs_alloc_rec_incore_t a;
251 xfs_bmbt_irec_t b;
252 xfs_inobt_rec_incore_t i;
253 } bc_rec; /* current insert/search record value */
254 struct xfs_buf *bc_bufs[XFS_BTREE_MAXLEVELS]; /* buf ptr per level */
255 int bc_ptrs[XFS_BTREE_MAXLEVELS]; /* key/record # */
256 __uint8_t bc_ra[XFS_BTREE_MAXLEVELS]; /* readahead bits */
257 #define XFS_BTCUR_LEFTRA 1 /* left sibling has been read-ahead */
258 #define XFS_BTCUR_RIGHTRA 2 /* right sibling has been read-ahead */
259 __uint8_t bc_nlevels; /* number of levels in the tree */
260 __uint8_t bc_blocklog; /* log2(blocksize) of btree blocks */
261 xfs_btnum_t bc_btnum; /* identifies which btree type */
262 union {
263 struct { /* needed for BNO, CNT, INO */
264 struct xfs_buf *agbp; /* agf/agi buffer pointer */
265 xfs_agnumber_t agno; /* ag number */
266 } a;
267 struct { /* needed for BMAP */
268 struct xfs_inode *ip; /* pointer to our inode */
269 struct xfs_bmap_free *flist; /* list to free after */
270 xfs_fsblock_t firstblock; /* 1st blk allocated */
271 int allocated; /* count of alloced */
272 short forksize; /* fork's inode space */
273 char whichfork; /* data or attr fork */
274 char flags; /* flags */
275 #define XFS_BTCUR_BPRV_WASDEL 1 /* was delayed */
276 } b;
277 } bc_private; /* per-btree type data */
278 } xfs_btree_cur_t;
279
280 /* cursor flags */
281 #define XFS_BTREE_LONG_PTRS (1<<0) /* pointers are 64bits long */
282 #define XFS_BTREE_ROOT_IN_INODE (1<<1) /* root may be variable size */
283 #define XFS_BTREE_LASTREC_UPDATE (1<<2) /* track last rec externally */
284 #define XFS_BTREE_CRC_BLOCKS (1<<3) /* uses extended btree blocks */
285
286
287 #define XFS_BTREE_NOERROR 0
288 #define XFS_BTREE_ERROR 1
289
290 /*
291 * Convert from buffer to btree block header.
292 */
293 #define XFS_BUF_TO_BLOCK(bp) ((struct xfs_btree_block *)((bp)->b_addr))
294
295
296 /*
297 * Check that block header is ok.
298 */
299 int
300 xfs_btree_check_block(
301 struct xfs_btree_cur *cur, /* btree cursor */
302 struct xfs_btree_block *block, /* generic btree block pointer */
303 int level, /* level of the btree block */
304 struct xfs_buf *bp); /* buffer containing block, if any */
305
306 /*
307 * Check that (long) pointer is ok.
308 */
309 int /* error (0 or EFSCORRUPTED) */
310 xfs_btree_check_lptr(
311 struct xfs_btree_cur *cur, /* btree cursor */
312 xfs_dfsbno_t ptr, /* btree block disk address */
313 int level); /* btree block level */
314
315 /*
316 * Delete the btree cursor.
317 */
318 void
319 xfs_btree_del_cursor(
320 xfs_btree_cur_t *cur, /* btree cursor */
321 int error); /* del because of error */
322
323 /*
324 * Duplicate the btree cursor.
325 * Allocate a new one, copy the record, re-get the buffers.
326 */
327 int /* error */
328 xfs_btree_dup_cursor(
329 xfs_btree_cur_t *cur, /* input cursor */
330 xfs_btree_cur_t **ncur);/* output cursor */
331
332 /*
333 * Get a buffer for the block, return it with no data read.
334 * Long-form addressing.
335 */
336 struct xfs_buf * /* buffer for fsbno */
337 xfs_btree_get_bufl(
338 struct xfs_mount *mp, /* file system mount point */
339 struct xfs_trans *tp, /* transaction pointer */
340 xfs_fsblock_t fsbno, /* file system block number */
341 uint lock); /* lock flags for get_buf */
342
343 /*
344 * Get a buffer for the block, return it with no data read.
345 * Short-form addressing.
346 */
347 struct xfs_buf * /* buffer for agno/agbno */
348 xfs_btree_get_bufs(
349 struct xfs_mount *mp, /* file system mount point */
350 struct xfs_trans *tp, /* transaction pointer */
351 xfs_agnumber_t agno, /* allocation group number */
352 xfs_agblock_t agbno, /* allocation group block number */
353 uint lock); /* lock flags for get_buf */
354
355 /*
356 * Check for the cursor referring to the last block at the given level.
357 */
358 int /* 1=is last block, 0=not last block */
359 xfs_btree_islastblock(
360 xfs_btree_cur_t *cur, /* btree cursor */
361 int level); /* level to check */
362
363 /*
364 * Compute first and last byte offsets for the fields given.
365 * Interprets the offsets table, which contains struct field offsets.
366 */
367 void
368 xfs_btree_offsets(
369 __int64_t fields, /* bitmask of fields */
370 const short *offsets,/* table of field offsets */
371 int nbits, /* number of bits to inspect */
372 int *first, /* output: first byte offset */
373 int *last); /* output: last byte offset */
374
375 /*
376 * Get a buffer for the block, return it read in.
377 * Long-form addressing.
378 */
379 int /* error */
380 xfs_btree_read_bufl(
381 struct xfs_mount *mp, /* file system mount point */
382 struct xfs_trans *tp, /* transaction pointer */
383 xfs_fsblock_t fsbno, /* file system block number */
384 uint lock, /* lock flags for read_buf */
385 struct xfs_buf **bpp, /* buffer for fsbno */
386 int refval, /* ref count value for buffer */
387 const struct xfs_buf_ops *ops);
388
389 /*
390 * Read-ahead the block, don't wait for it, don't return a buffer.
391 * Long-form addressing.
392 */
393 void /* error */
394 xfs_btree_reada_bufl(
395 struct xfs_mount *mp, /* file system mount point */
396 xfs_fsblock_t fsbno, /* file system block number */
397 xfs_extlen_t count, /* count of filesystem blocks */
398 const struct xfs_buf_ops *ops);
399
400 /*
401 * Read-ahead the block, don't wait for it, don't return a buffer.
402 * Short-form addressing.
403 */
404 void /* error */
405 xfs_btree_reada_bufs(
406 struct xfs_mount *mp, /* file system mount point */
407 xfs_agnumber_t agno, /* allocation group number */
408 xfs_agblock_t agbno, /* allocation group block number */
409 xfs_extlen_t count, /* count of filesystem blocks */
410 const struct xfs_buf_ops *ops);
411
412 /*
413 * Initialise a new btree block header
414 */
415 void
416 xfs_btree_init_block(
417 struct xfs_mount *mp,
418 struct xfs_buf *bp,
419 __u32 magic,
420 __u16 level,
421 __u16 numrecs,
422 __u64 owner,
423 unsigned int flags);
424
425 void
426 xfs_btree_init_block_int(
427 struct xfs_mount *mp,
428 struct xfs_btree_block *buf,
429 xfs_daddr_t blkno,
430 __u32 magic,
431 __u16 level,
432 __u16 numrecs,
433 __u64 owner,
434 unsigned int flags);
435
436 /*
437 * Common btree core entry points.
438 */
439 int xfs_btree_increment(struct xfs_btree_cur *, int, int *);
440 int xfs_btree_decrement(struct xfs_btree_cur *, int, int *);
441 int xfs_btree_lookup(struct xfs_btree_cur *, xfs_lookup_t, int *);
442 int xfs_btree_update(struct xfs_btree_cur *, union xfs_btree_rec *);
443 int xfs_btree_new_iroot(struct xfs_btree_cur *, int *, int *);
444 int xfs_btree_insert(struct xfs_btree_cur *, int *);
445 int xfs_btree_delete(struct xfs_btree_cur *, int *);
446 int xfs_btree_get_rec(struct xfs_btree_cur *, union xfs_btree_rec **, int *);
447
448 /*
449 * btree block CRC helpers
450 */
451 void xfs_btree_lblock_calc_crc(struct xfs_buf *);
452 bool xfs_btree_lblock_verify_crc(struct xfs_buf *);
453 void xfs_btree_sblock_calc_crc(struct xfs_buf *);
454 bool xfs_btree_sblock_verify_crc(struct xfs_buf *);
455
456 /*
457 * Internal btree helpers also used by xfs_bmap.c.
458 */
459 void xfs_btree_log_block(struct xfs_btree_cur *, struct xfs_buf *, int);
460 void xfs_btree_log_recs(struct xfs_btree_cur *, struct xfs_buf *, int, int);
461
462 /*
463 * Helpers.
464 */
xfs_btree_get_numrecs(struct xfs_btree_block * block)465 static inline int xfs_btree_get_numrecs(struct xfs_btree_block *block)
466 {
467 return be16_to_cpu(block->bb_numrecs);
468 }
469
xfs_btree_set_numrecs(struct xfs_btree_block * block,__uint16_t numrecs)470 static inline void xfs_btree_set_numrecs(struct xfs_btree_block *block,
471 __uint16_t numrecs)
472 {
473 block->bb_numrecs = cpu_to_be16(numrecs);
474 }
475
xfs_btree_get_level(struct xfs_btree_block * block)476 static inline int xfs_btree_get_level(struct xfs_btree_block *block)
477 {
478 return be16_to_cpu(block->bb_level);
479 }
480
481
482 /*
483 * Min and max functions for extlen, agblock, fileoff, and filblks types.
484 */
485 #define XFS_EXTLEN_MIN(a,b) min_t(xfs_extlen_t, (a), (b))
486 #define XFS_EXTLEN_MAX(a,b) max_t(xfs_extlen_t, (a), (b))
487 #define XFS_AGBLOCK_MIN(a,b) min_t(xfs_agblock_t, (a), (b))
488 #define XFS_AGBLOCK_MAX(a,b) max_t(xfs_agblock_t, (a), (b))
489 #define XFS_FILEOFF_MIN(a,b) min_t(xfs_fileoff_t, (a), (b))
490 #define XFS_FILEOFF_MAX(a,b) max_t(xfs_fileoff_t, (a), (b))
491 #define XFS_FILBLKS_MIN(a,b) min_t(xfs_filblks_t, (a), (b))
492 #define XFS_FILBLKS_MAX(a,b) max_t(xfs_filblks_t, (a), (b))
493
494 #define XFS_FSB_SANITY_CHECK(mp,fsb) \
495 (XFS_FSB_TO_AGNO(mp, fsb) < mp->m_sb.sb_agcount && \
496 XFS_FSB_TO_AGBNO(mp, fsb) < mp->m_sb.sb_agblocks)
497
498 /*
499 * Trace hooks. Currently not implemented as they need to be ported
500 * over to the generic tracing functionality, which is some effort.
501 *
502 * i,j = integer (32 bit)
503 * b = btree block buffer (xfs_buf_t)
504 * p = btree ptr
505 * r = btree record
506 * k = btree key
507 */
508 #define XFS_BTREE_TRACE_ARGBI(c, b, i)
509 #define XFS_BTREE_TRACE_ARGBII(c, b, i, j)
510 #define XFS_BTREE_TRACE_ARGI(c, i)
511 #define XFS_BTREE_TRACE_ARGIPK(c, i, p, s)
512 #define XFS_BTREE_TRACE_ARGIPR(c, i, p, r)
513 #define XFS_BTREE_TRACE_ARGIK(c, i, k)
514 #define XFS_BTREE_TRACE_ARGR(c, r)
515 #define XFS_BTREE_TRACE_CURSOR(c, t)
516
517 #endif /* __XFS_BTREE_H__ */
518