xref: /linux/fs/xfs/libxfs/xfs_alloc_btree.c (revision a06c3fad49a50d5d5eb078f93e70f4d3eca5d5a5)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
4  * All Rights Reserved.
5  */
6 #include "xfs.h"
7 #include "xfs_fs.h"
8 #include "xfs_shared.h"
9 #include "xfs_format.h"
10 #include "xfs_log_format.h"
11 #include "xfs_trans_resv.h"
12 #include "xfs_mount.h"
13 #include "xfs_btree.h"
14 #include "xfs_btree_staging.h"
15 #include "xfs_alloc_btree.h"
16 #include "xfs_alloc.h"
17 #include "xfs_extent_busy.h"
18 #include "xfs_error.h"
19 #include "xfs_health.h"
20 #include "xfs_trace.h"
21 #include "xfs_trans.h"
22 #include "xfs_ag.h"
23 
24 static struct kmem_cache	*xfs_allocbt_cur_cache;
25 
26 STATIC struct xfs_btree_cur *
27 xfs_bnobt_dup_cursor(
28 	struct xfs_btree_cur	*cur)
29 {
30 	return xfs_bnobt_init_cursor(cur->bc_mp, cur->bc_tp, cur->bc_ag.agbp,
31 			cur->bc_ag.pag);
32 }
33 
34 STATIC struct xfs_btree_cur *
35 xfs_cntbt_dup_cursor(
36 	struct xfs_btree_cur	*cur)
37 {
38 	return xfs_cntbt_init_cursor(cur->bc_mp, cur->bc_tp, cur->bc_ag.agbp,
39 			cur->bc_ag.pag);
40 }
41 
42 
43 STATIC void
44 xfs_allocbt_set_root(
45 	struct xfs_btree_cur		*cur,
46 	const union xfs_btree_ptr	*ptr,
47 	int				inc)
48 {
49 	struct xfs_buf		*agbp = cur->bc_ag.agbp;
50 	struct xfs_agf		*agf = agbp->b_addr;
51 
52 	ASSERT(ptr->s != 0);
53 
54 	if (xfs_btree_is_bno(cur->bc_ops)) {
55 		agf->agf_bno_root = ptr->s;
56 		be32_add_cpu(&agf->agf_bno_level, inc);
57 		cur->bc_ag.pag->pagf_bno_level += inc;
58 	} else {
59 		agf->agf_cnt_root = ptr->s;
60 		be32_add_cpu(&agf->agf_cnt_level, inc);
61 		cur->bc_ag.pag->pagf_cnt_level += inc;
62 	}
63 
64 	xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_ROOTS | XFS_AGF_LEVELS);
65 }
66 
67 STATIC int
68 xfs_allocbt_alloc_block(
69 	struct xfs_btree_cur		*cur,
70 	const union xfs_btree_ptr	*start,
71 	union xfs_btree_ptr		*new,
72 	int				*stat)
73 {
74 	int			error;
75 	xfs_agblock_t		bno;
76 
77 	/* Allocate the new block from the freelist. If we can't, give up.  */
78 	error = xfs_alloc_get_freelist(cur->bc_ag.pag, cur->bc_tp,
79 			cur->bc_ag.agbp, &bno, 1);
80 	if (error)
81 		return error;
82 
83 	if (bno == NULLAGBLOCK) {
84 		*stat = 0;
85 		return 0;
86 	}
87 
88 	atomic64_inc(&cur->bc_mp->m_allocbt_blks);
89 	xfs_extent_busy_reuse(cur->bc_mp, cur->bc_ag.pag, bno, 1, false);
90 
91 	new->s = cpu_to_be32(bno);
92 
93 	*stat = 1;
94 	return 0;
95 }
96 
97 STATIC int
98 xfs_allocbt_free_block(
99 	struct xfs_btree_cur	*cur,
100 	struct xfs_buf		*bp)
101 {
102 	struct xfs_buf		*agbp = cur->bc_ag.agbp;
103 	xfs_agblock_t		bno;
104 	int			error;
105 
106 	bno = xfs_daddr_to_agbno(cur->bc_mp, xfs_buf_daddr(bp));
107 	error = xfs_alloc_put_freelist(cur->bc_ag.pag, cur->bc_tp, agbp, NULL,
108 			bno, 1);
109 	if (error)
110 		return error;
111 
112 	atomic64_dec(&cur->bc_mp->m_allocbt_blks);
113 	xfs_extent_busy_insert(cur->bc_tp, agbp->b_pag, bno, 1,
114 			      XFS_EXTENT_BUSY_SKIP_DISCARD);
115 	return 0;
116 }
117 
118 STATIC int
119 xfs_allocbt_get_minrecs(
120 	struct xfs_btree_cur	*cur,
121 	int			level)
122 {
123 	return cur->bc_mp->m_alloc_mnr[level != 0];
124 }
125 
126 STATIC int
127 xfs_allocbt_get_maxrecs(
128 	struct xfs_btree_cur	*cur,
129 	int			level)
130 {
131 	return cur->bc_mp->m_alloc_mxr[level != 0];
132 }
133 
134 STATIC void
135 xfs_allocbt_init_key_from_rec(
136 	union xfs_btree_key		*key,
137 	const union xfs_btree_rec	*rec)
138 {
139 	key->alloc.ar_startblock = rec->alloc.ar_startblock;
140 	key->alloc.ar_blockcount = rec->alloc.ar_blockcount;
141 }
142 
143 STATIC void
144 xfs_bnobt_init_high_key_from_rec(
145 	union xfs_btree_key		*key,
146 	const union xfs_btree_rec	*rec)
147 {
148 	__u32				x;
149 
150 	x = be32_to_cpu(rec->alloc.ar_startblock);
151 	x += be32_to_cpu(rec->alloc.ar_blockcount) - 1;
152 	key->alloc.ar_startblock = cpu_to_be32(x);
153 	key->alloc.ar_blockcount = 0;
154 }
155 
156 STATIC void
157 xfs_cntbt_init_high_key_from_rec(
158 	union xfs_btree_key		*key,
159 	const union xfs_btree_rec	*rec)
160 {
161 	key->alloc.ar_blockcount = rec->alloc.ar_blockcount;
162 	key->alloc.ar_startblock = 0;
163 }
164 
165 STATIC void
166 xfs_allocbt_init_rec_from_cur(
167 	struct xfs_btree_cur	*cur,
168 	union xfs_btree_rec	*rec)
169 {
170 	rec->alloc.ar_startblock = cpu_to_be32(cur->bc_rec.a.ar_startblock);
171 	rec->alloc.ar_blockcount = cpu_to_be32(cur->bc_rec.a.ar_blockcount);
172 }
173 
174 STATIC void
175 xfs_allocbt_init_ptr_from_cur(
176 	struct xfs_btree_cur	*cur,
177 	union xfs_btree_ptr	*ptr)
178 {
179 	struct xfs_agf		*agf = cur->bc_ag.agbp->b_addr;
180 
181 	ASSERT(cur->bc_ag.pag->pag_agno == be32_to_cpu(agf->agf_seqno));
182 
183 	if (xfs_btree_is_bno(cur->bc_ops))
184 		ptr->s = agf->agf_bno_root;
185 	else
186 		ptr->s = agf->agf_cnt_root;
187 }
188 
189 STATIC int64_t
190 xfs_bnobt_key_diff(
191 	struct xfs_btree_cur		*cur,
192 	const union xfs_btree_key	*key)
193 {
194 	struct xfs_alloc_rec_incore	*rec = &cur->bc_rec.a;
195 	const struct xfs_alloc_rec	*kp = &key->alloc;
196 
197 	return (int64_t)be32_to_cpu(kp->ar_startblock) - rec->ar_startblock;
198 }
199 
200 STATIC int64_t
201 xfs_cntbt_key_diff(
202 	struct xfs_btree_cur		*cur,
203 	const union xfs_btree_key	*key)
204 {
205 	struct xfs_alloc_rec_incore	*rec = &cur->bc_rec.a;
206 	const struct xfs_alloc_rec	*kp = &key->alloc;
207 	int64_t				diff;
208 
209 	diff = (int64_t)be32_to_cpu(kp->ar_blockcount) - rec->ar_blockcount;
210 	if (diff)
211 		return diff;
212 
213 	return (int64_t)be32_to_cpu(kp->ar_startblock) - rec->ar_startblock;
214 }
215 
216 STATIC int64_t
217 xfs_bnobt_diff_two_keys(
218 	struct xfs_btree_cur		*cur,
219 	const union xfs_btree_key	*k1,
220 	const union xfs_btree_key	*k2,
221 	const union xfs_btree_key	*mask)
222 {
223 	ASSERT(!mask || mask->alloc.ar_startblock);
224 
225 	return (int64_t)be32_to_cpu(k1->alloc.ar_startblock) -
226 			be32_to_cpu(k2->alloc.ar_startblock);
227 }
228 
229 STATIC int64_t
230 xfs_cntbt_diff_two_keys(
231 	struct xfs_btree_cur		*cur,
232 	const union xfs_btree_key	*k1,
233 	const union xfs_btree_key	*k2,
234 	const union xfs_btree_key	*mask)
235 {
236 	int64_t				diff;
237 
238 	ASSERT(!mask || (mask->alloc.ar_blockcount &&
239 			 mask->alloc.ar_startblock));
240 
241 	diff =  be32_to_cpu(k1->alloc.ar_blockcount) -
242 		be32_to_cpu(k2->alloc.ar_blockcount);
243 	if (diff)
244 		return diff;
245 
246 	return  be32_to_cpu(k1->alloc.ar_startblock) -
247 		be32_to_cpu(k2->alloc.ar_startblock);
248 }
249 
250 static xfs_failaddr_t
251 xfs_allocbt_verify(
252 	struct xfs_buf		*bp)
253 {
254 	struct xfs_mount	*mp = bp->b_mount;
255 	struct xfs_btree_block	*block = XFS_BUF_TO_BLOCK(bp);
256 	struct xfs_perag	*pag = bp->b_pag;
257 	xfs_failaddr_t		fa;
258 	unsigned int		level;
259 
260 	if (!xfs_verify_magic(bp, block->bb_magic))
261 		return __this_address;
262 
263 	if (xfs_has_crc(mp)) {
264 		fa = xfs_btree_agblock_v5hdr_verify(bp);
265 		if (fa)
266 			return fa;
267 	}
268 
269 	/*
270 	 * The perag may not be attached during grow operations or fully
271 	 * initialized from the AGF during log recovery. Therefore we can only
272 	 * check against maximum tree depth from those contexts.
273 	 *
274 	 * Otherwise check against the per-tree limit. Peek at one of the
275 	 * verifier magic values to determine the type of tree we're verifying
276 	 * against.
277 	 */
278 	level = be16_to_cpu(block->bb_level);
279 	if (pag && xfs_perag_initialised_agf(pag)) {
280 		unsigned int	maxlevel, repair_maxlevel = 0;
281 
282 		/*
283 		 * Online repair could be rewriting the free space btrees, so
284 		 * we'll validate against the larger of either tree while this
285 		 * is going on.
286 		 */
287 		if (bp->b_ops->magic[0] == cpu_to_be32(XFS_ABTC_MAGIC)) {
288 			maxlevel = pag->pagf_cnt_level;
289 #ifdef CONFIG_XFS_ONLINE_REPAIR
290 			repair_maxlevel = pag->pagf_repair_cnt_level;
291 #endif
292 		} else {
293 			maxlevel = pag->pagf_bno_level;
294 #ifdef CONFIG_XFS_ONLINE_REPAIR
295 			repair_maxlevel = pag->pagf_repair_bno_level;
296 #endif
297 		}
298 
299 		if (level >= max(maxlevel, repair_maxlevel))
300 			return __this_address;
301 	} else if (level >= mp->m_alloc_maxlevels)
302 		return __this_address;
303 
304 	return xfs_btree_agblock_verify(bp, mp->m_alloc_mxr[level != 0]);
305 }
306 
307 static void
308 xfs_allocbt_read_verify(
309 	struct xfs_buf	*bp)
310 {
311 	xfs_failaddr_t	fa;
312 
313 	if (!xfs_btree_agblock_verify_crc(bp))
314 		xfs_verifier_error(bp, -EFSBADCRC, __this_address);
315 	else {
316 		fa = xfs_allocbt_verify(bp);
317 		if (fa)
318 			xfs_verifier_error(bp, -EFSCORRUPTED, fa);
319 	}
320 
321 	if (bp->b_error)
322 		trace_xfs_btree_corrupt(bp, _RET_IP_);
323 }
324 
325 static void
326 xfs_allocbt_write_verify(
327 	struct xfs_buf	*bp)
328 {
329 	xfs_failaddr_t	fa;
330 
331 	fa = xfs_allocbt_verify(bp);
332 	if (fa) {
333 		trace_xfs_btree_corrupt(bp, _RET_IP_);
334 		xfs_verifier_error(bp, -EFSCORRUPTED, fa);
335 		return;
336 	}
337 	xfs_btree_agblock_calc_crc(bp);
338 
339 }
340 
341 const struct xfs_buf_ops xfs_bnobt_buf_ops = {
342 	.name = "xfs_bnobt",
343 	.magic = { cpu_to_be32(XFS_ABTB_MAGIC),
344 		   cpu_to_be32(XFS_ABTB_CRC_MAGIC) },
345 	.verify_read = xfs_allocbt_read_verify,
346 	.verify_write = xfs_allocbt_write_verify,
347 	.verify_struct = xfs_allocbt_verify,
348 };
349 
350 const struct xfs_buf_ops xfs_cntbt_buf_ops = {
351 	.name = "xfs_cntbt",
352 	.magic = { cpu_to_be32(XFS_ABTC_MAGIC),
353 		   cpu_to_be32(XFS_ABTC_CRC_MAGIC) },
354 	.verify_read = xfs_allocbt_read_verify,
355 	.verify_write = xfs_allocbt_write_verify,
356 	.verify_struct = xfs_allocbt_verify,
357 };
358 
359 STATIC int
360 xfs_bnobt_keys_inorder(
361 	struct xfs_btree_cur		*cur,
362 	const union xfs_btree_key	*k1,
363 	const union xfs_btree_key	*k2)
364 {
365 	return be32_to_cpu(k1->alloc.ar_startblock) <
366 	       be32_to_cpu(k2->alloc.ar_startblock);
367 }
368 
369 STATIC int
370 xfs_bnobt_recs_inorder(
371 	struct xfs_btree_cur		*cur,
372 	const union xfs_btree_rec	*r1,
373 	const union xfs_btree_rec	*r2)
374 {
375 	return be32_to_cpu(r1->alloc.ar_startblock) +
376 		be32_to_cpu(r1->alloc.ar_blockcount) <=
377 		be32_to_cpu(r2->alloc.ar_startblock);
378 }
379 
380 STATIC int
381 xfs_cntbt_keys_inorder(
382 	struct xfs_btree_cur		*cur,
383 	const union xfs_btree_key	*k1,
384 	const union xfs_btree_key	*k2)
385 {
386 	return be32_to_cpu(k1->alloc.ar_blockcount) <
387 		be32_to_cpu(k2->alloc.ar_blockcount) ||
388 		(k1->alloc.ar_blockcount == k2->alloc.ar_blockcount &&
389 		 be32_to_cpu(k1->alloc.ar_startblock) <
390 		 be32_to_cpu(k2->alloc.ar_startblock));
391 }
392 
393 STATIC int
394 xfs_cntbt_recs_inorder(
395 	struct xfs_btree_cur		*cur,
396 	const union xfs_btree_rec	*r1,
397 	const union xfs_btree_rec	*r2)
398 {
399 	return be32_to_cpu(r1->alloc.ar_blockcount) <
400 		be32_to_cpu(r2->alloc.ar_blockcount) ||
401 		(r1->alloc.ar_blockcount == r2->alloc.ar_blockcount &&
402 		 be32_to_cpu(r1->alloc.ar_startblock) <
403 		 be32_to_cpu(r2->alloc.ar_startblock));
404 }
405 
406 STATIC enum xbtree_key_contig
407 xfs_allocbt_keys_contiguous(
408 	struct xfs_btree_cur		*cur,
409 	const union xfs_btree_key	*key1,
410 	const union xfs_btree_key	*key2,
411 	const union xfs_btree_key	*mask)
412 {
413 	ASSERT(!mask || mask->alloc.ar_startblock);
414 
415 	return xbtree_key_contig(be32_to_cpu(key1->alloc.ar_startblock),
416 				 be32_to_cpu(key2->alloc.ar_startblock));
417 }
418 
419 const struct xfs_btree_ops xfs_bnobt_ops = {
420 	.name			= "bno",
421 	.type			= XFS_BTREE_TYPE_AG,
422 
423 	.rec_len		= sizeof(xfs_alloc_rec_t),
424 	.key_len		= sizeof(xfs_alloc_key_t),
425 	.ptr_len		= XFS_BTREE_SHORT_PTR_LEN,
426 
427 	.lru_refs		= XFS_ALLOC_BTREE_REF,
428 	.statoff		= XFS_STATS_CALC_INDEX(xs_abtb_2),
429 	.sick_mask		= XFS_SICK_AG_BNOBT,
430 
431 	.dup_cursor		= xfs_bnobt_dup_cursor,
432 	.set_root		= xfs_allocbt_set_root,
433 	.alloc_block		= xfs_allocbt_alloc_block,
434 	.free_block		= xfs_allocbt_free_block,
435 	.get_minrecs		= xfs_allocbt_get_minrecs,
436 	.get_maxrecs		= xfs_allocbt_get_maxrecs,
437 	.init_key_from_rec	= xfs_allocbt_init_key_from_rec,
438 	.init_high_key_from_rec	= xfs_bnobt_init_high_key_from_rec,
439 	.init_rec_from_cur	= xfs_allocbt_init_rec_from_cur,
440 	.init_ptr_from_cur	= xfs_allocbt_init_ptr_from_cur,
441 	.key_diff		= xfs_bnobt_key_diff,
442 	.buf_ops		= &xfs_bnobt_buf_ops,
443 	.diff_two_keys		= xfs_bnobt_diff_two_keys,
444 	.keys_inorder		= xfs_bnobt_keys_inorder,
445 	.recs_inorder		= xfs_bnobt_recs_inorder,
446 	.keys_contiguous	= xfs_allocbt_keys_contiguous,
447 };
448 
449 const struct xfs_btree_ops xfs_cntbt_ops = {
450 	.name			= "cnt",
451 	.type			= XFS_BTREE_TYPE_AG,
452 
453 	.rec_len		= sizeof(xfs_alloc_rec_t),
454 	.key_len		= sizeof(xfs_alloc_key_t),
455 	.ptr_len		= XFS_BTREE_SHORT_PTR_LEN,
456 
457 	.lru_refs		= XFS_ALLOC_BTREE_REF,
458 	.statoff		= XFS_STATS_CALC_INDEX(xs_abtc_2),
459 	.sick_mask		= XFS_SICK_AG_CNTBT,
460 
461 	.dup_cursor		= xfs_cntbt_dup_cursor,
462 	.set_root		= xfs_allocbt_set_root,
463 	.alloc_block		= xfs_allocbt_alloc_block,
464 	.free_block		= xfs_allocbt_free_block,
465 	.get_minrecs		= xfs_allocbt_get_minrecs,
466 	.get_maxrecs		= xfs_allocbt_get_maxrecs,
467 	.init_key_from_rec	= xfs_allocbt_init_key_from_rec,
468 	.init_high_key_from_rec	= xfs_cntbt_init_high_key_from_rec,
469 	.init_rec_from_cur	= xfs_allocbt_init_rec_from_cur,
470 	.init_ptr_from_cur	= xfs_allocbt_init_ptr_from_cur,
471 	.key_diff		= xfs_cntbt_key_diff,
472 	.buf_ops		= &xfs_cntbt_buf_ops,
473 	.diff_two_keys		= xfs_cntbt_diff_two_keys,
474 	.keys_inorder		= xfs_cntbt_keys_inorder,
475 	.recs_inorder		= xfs_cntbt_recs_inorder,
476 	.keys_contiguous	= NULL, /* not needed right now */
477 };
478 
479 /*
480  * Allocate a new bnobt cursor.
481  *
482  * For staging cursors tp and agbp are NULL.
483  */
484 struct xfs_btree_cur *
485 xfs_bnobt_init_cursor(
486 	struct xfs_mount	*mp,
487 	struct xfs_trans	*tp,
488 	struct xfs_buf		*agbp,
489 	struct xfs_perag	*pag)
490 {
491 	struct xfs_btree_cur	*cur;
492 
493 	cur = xfs_btree_alloc_cursor(mp, tp, &xfs_bnobt_ops,
494 			mp->m_alloc_maxlevels, xfs_allocbt_cur_cache);
495 	cur->bc_ag.pag = xfs_perag_hold(pag);
496 	cur->bc_ag.agbp = agbp;
497 	if (agbp) {
498 		struct xfs_agf		*agf = agbp->b_addr;
499 
500 		cur->bc_nlevels = be32_to_cpu(agf->agf_bno_level);
501 	}
502 	return cur;
503 }
504 
505 /*
506  * Allocate a new cntbt cursor.
507  *
508  * For staging cursors tp and agbp are NULL.
509  */
510 struct xfs_btree_cur *
511 xfs_cntbt_init_cursor(
512 	struct xfs_mount	*mp,
513 	struct xfs_trans	*tp,
514 	struct xfs_buf		*agbp,
515 	struct xfs_perag	*pag)
516 {
517 	struct xfs_btree_cur	*cur;
518 
519 	cur = xfs_btree_alloc_cursor(mp, tp, &xfs_cntbt_ops,
520 			mp->m_alloc_maxlevels, xfs_allocbt_cur_cache);
521 	cur->bc_ag.pag = xfs_perag_hold(pag);
522 	cur->bc_ag.agbp = agbp;
523 	if (agbp) {
524 		struct xfs_agf		*agf = agbp->b_addr;
525 
526 		cur->bc_nlevels = be32_to_cpu(agf->agf_cnt_level);
527 	}
528 	return cur;
529 }
530 
531 /*
532  * Install a new free space btree root.  Caller is responsible for invalidating
533  * and freeing the old btree blocks.
534  */
535 void
536 xfs_allocbt_commit_staged_btree(
537 	struct xfs_btree_cur	*cur,
538 	struct xfs_trans	*tp,
539 	struct xfs_buf		*agbp)
540 {
541 	struct xfs_agf		*agf = agbp->b_addr;
542 	struct xbtree_afakeroot	*afake = cur->bc_ag.afake;
543 
544 	ASSERT(cur->bc_flags & XFS_BTREE_STAGING);
545 
546 	if (xfs_btree_is_bno(cur->bc_ops)) {
547 		agf->agf_bno_root = cpu_to_be32(afake->af_root);
548 		agf->agf_bno_level = cpu_to_be32(afake->af_levels);
549 	} else {
550 		agf->agf_cnt_root = cpu_to_be32(afake->af_root);
551 		agf->agf_cnt_level = cpu_to_be32(afake->af_levels);
552 	}
553 	xfs_alloc_log_agf(tp, agbp, XFS_AGF_ROOTS | XFS_AGF_LEVELS);
554 
555 	xfs_btree_commit_afakeroot(cur, tp, agbp);
556 }
557 
558 /* Calculate number of records in an alloc btree block. */
559 static inline unsigned int
560 xfs_allocbt_block_maxrecs(
561 	unsigned int		blocklen,
562 	bool			leaf)
563 {
564 	if (leaf)
565 		return blocklen / sizeof(xfs_alloc_rec_t);
566 	return blocklen / (sizeof(xfs_alloc_key_t) + sizeof(xfs_alloc_ptr_t));
567 }
568 
569 /*
570  * Calculate number of records in an alloc btree block.
571  */
572 int
573 xfs_allocbt_maxrecs(
574 	struct xfs_mount	*mp,
575 	int			blocklen,
576 	int			leaf)
577 {
578 	blocklen -= XFS_ALLOC_BLOCK_LEN(mp);
579 	return xfs_allocbt_block_maxrecs(blocklen, leaf);
580 }
581 
582 /* Free space btrees are at their largest when every other block is free. */
583 #define XFS_MAX_FREESP_RECORDS	((XFS_MAX_AG_BLOCKS + 1) / 2)
584 
585 /* Compute the max possible height for free space btrees. */
586 unsigned int
587 xfs_allocbt_maxlevels_ondisk(void)
588 {
589 	unsigned int		minrecs[2];
590 	unsigned int		blocklen;
591 
592 	blocklen = min(XFS_MIN_BLOCKSIZE - XFS_BTREE_SBLOCK_LEN,
593 		       XFS_MIN_CRC_BLOCKSIZE - XFS_BTREE_SBLOCK_CRC_LEN);
594 
595 	minrecs[0] = xfs_allocbt_block_maxrecs(blocklen, true) / 2;
596 	minrecs[1] = xfs_allocbt_block_maxrecs(blocklen, false) / 2;
597 
598 	return xfs_btree_compute_maxlevels(minrecs, XFS_MAX_FREESP_RECORDS);
599 }
600 
601 /* Calculate the freespace btree size for some records. */
602 xfs_extlen_t
603 xfs_allocbt_calc_size(
604 	struct xfs_mount	*mp,
605 	unsigned long long	len)
606 {
607 	return xfs_btree_calc_size(mp->m_alloc_mnr, len);
608 }
609 
610 int __init
611 xfs_allocbt_init_cur_cache(void)
612 {
613 	xfs_allocbt_cur_cache = kmem_cache_create("xfs_bnobt_cur",
614 			xfs_btree_cur_sizeof(xfs_allocbt_maxlevels_ondisk()),
615 			0, 0, NULL);
616 
617 	if (!xfs_allocbt_cur_cache)
618 		return -ENOMEM;
619 	return 0;
620 }
621 
622 void
623 xfs_allocbt_destroy_cur_cache(void)
624 {
625 	kmem_cache_destroy(xfs_allocbt_cur_cache);
626 	xfs_allocbt_cur_cache = NULL;
627 }
628