xref: /openbmc/linux/fs/xfs/libxfs/xfs_alloc_btree.c (revision 612a462a)
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 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_shared.h"
21 #include "xfs_format.h"
22 #include "xfs_log_format.h"
23 #include "xfs_trans_resv.h"
24 #include "xfs_sb.h"
25 #include "xfs_mount.h"
26 #include "xfs_btree.h"
27 #include "xfs_alloc_btree.h"
28 #include "xfs_alloc.h"
29 #include "xfs_extent_busy.h"
30 #include "xfs_error.h"
31 #include "xfs_trace.h"
32 #include "xfs_cksum.h"
33 #include "xfs_trans.h"
34 
35 
36 STATIC struct xfs_btree_cur *
37 xfs_allocbt_dup_cursor(
38 	struct xfs_btree_cur	*cur)
39 {
40 	return xfs_allocbt_init_cursor(cur->bc_mp, cur->bc_tp,
41 			cur->bc_private.a.agbp, cur->bc_private.a.agno,
42 			cur->bc_btnum);
43 }
44 
45 STATIC void
46 xfs_allocbt_set_root(
47 	struct xfs_btree_cur	*cur,
48 	union xfs_btree_ptr	*ptr,
49 	int			inc)
50 {
51 	struct xfs_buf		*agbp = cur->bc_private.a.agbp;
52 	struct xfs_agf		*agf = XFS_BUF_TO_AGF(agbp);
53 	xfs_agnumber_t		seqno = be32_to_cpu(agf->agf_seqno);
54 	int			btnum = cur->bc_btnum;
55 	struct xfs_perag	*pag = xfs_perag_get(cur->bc_mp, seqno);
56 
57 	ASSERT(ptr->s != 0);
58 
59 	agf->agf_roots[btnum] = ptr->s;
60 	be32_add_cpu(&agf->agf_levels[btnum], inc);
61 	pag->pagf_levels[btnum] += inc;
62 	xfs_perag_put(pag);
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 	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 	XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
78 
79 	/* Allocate the new block from the freelist. If we can't, give up.  */
80 	error = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_private.a.agbp,
81 				       &bno, 1);
82 	if (error) {
83 		XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
84 		return error;
85 	}
86 
87 	if (bno == NULLAGBLOCK) {
88 		XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
89 		*stat = 0;
90 		return 0;
91 	}
92 
93 	xfs_extent_busy_reuse(cur->bc_mp, cur->bc_private.a.agno, bno, 1, false);
94 
95 	xfs_trans_agbtree_delta(cur->bc_tp, 1);
96 	new->s = cpu_to_be32(bno);
97 
98 	XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
99 	*stat = 1;
100 	return 0;
101 }
102 
103 STATIC int
104 xfs_allocbt_free_block(
105 	struct xfs_btree_cur	*cur,
106 	struct xfs_buf		*bp)
107 {
108 	struct xfs_buf		*agbp = cur->bc_private.a.agbp;
109 	struct xfs_agf		*agf = XFS_BUF_TO_AGF(agbp);
110 	xfs_agblock_t		bno;
111 	int			error;
112 
113 	bno = xfs_daddr_to_agbno(cur->bc_mp, XFS_BUF_ADDR(bp));
114 	error = xfs_alloc_put_freelist(cur->bc_tp, agbp, NULL, bno, 1);
115 	if (error)
116 		return error;
117 
118 	xfs_extent_busy_insert(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1,
119 			      XFS_EXTENT_BUSY_SKIP_DISCARD);
120 	xfs_trans_agbtree_delta(cur->bc_tp, -1);
121 	return 0;
122 }
123 
124 /*
125  * Update the longest extent in the AGF
126  */
127 STATIC void
128 xfs_allocbt_update_lastrec(
129 	struct xfs_btree_cur	*cur,
130 	struct xfs_btree_block	*block,
131 	union xfs_btree_rec	*rec,
132 	int			ptr,
133 	int			reason)
134 {
135 	struct xfs_agf		*agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
136 	xfs_agnumber_t		seqno = be32_to_cpu(agf->agf_seqno);
137 	struct xfs_perag	*pag;
138 	__be32			len;
139 	int			numrecs;
140 
141 	ASSERT(cur->bc_btnum == XFS_BTNUM_CNT);
142 
143 	switch (reason) {
144 	case LASTREC_UPDATE:
145 		/*
146 		 * If this is the last leaf block and it's the last record,
147 		 * then update the size of the longest extent in the AG.
148 		 */
149 		if (ptr != xfs_btree_get_numrecs(block))
150 			return;
151 		len = rec->alloc.ar_blockcount;
152 		break;
153 	case LASTREC_INSREC:
154 		if (be32_to_cpu(rec->alloc.ar_blockcount) <=
155 		    be32_to_cpu(agf->agf_longest))
156 			return;
157 		len = rec->alloc.ar_blockcount;
158 		break;
159 	case LASTREC_DELREC:
160 		numrecs = xfs_btree_get_numrecs(block);
161 		if (ptr <= numrecs)
162 			return;
163 		ASSERT(ptr == numrecs + 1);
164 
165 		if (numrecs) {
166 			xfs_alloc_rec_t *rrp;
167 
168 			rrp = XFS_ALLOC_REC_ADDR(cur->bc_mp, block, numrecs);
169 			len = rrp->ar_blockcount;
170 		} else {
171 			len = 0;
172 		}
173 
174 		break;
175 	default:
176 		ASSERT(0);
177 		return;
178 	}
179 
180 	agf->agf_longest = len;
181 	pag = xfs_perag_get(cur->bc_mp, seqno);
182 	pag->pagf_longest = be32_to_cpu(len);
183 	xfs_perag_put(pag);
184 	xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp, XFS_AGF_LONGEST);
185 }
186 
187 STATIC int
188 xfs_allocbt_get_minrecs(
189 	struct xfs_btree_cur	*cur,
190 	int			level)
191 {
192 	return cur->bc_mp->m_alloc_mnr[level != 0];
193 }
194 
195 STATIC int
196 xfs_allocbt_get_maxrecs(
197 	struct xfs_btree_cur	*cur,
198 	int			level)
199 {
200 	return cur->bc_mp->m_alloc_mxr[level != 0];
201 }
202 
203 STATIC void
204 xfs_allocbt_init_key_from_rec(
205 	union xfs_btree_key	*key,
206 	union xfs_btree_rec	*rec)
207 {
208 	key->alloc.ar_startblock = rec->alloc.ar_startblock;
209 	key->alloc.ar_blockcount = rec->alloc.ar_blockcount;
210 }
211 
212 STATIC void
213 xfs_bnobt_init_high_key_from_rec(
214 	union xfs_btree_key	*key,
215 	union xfs_btree_rec	*rec)
216 {
217 	__u32			x;
218 
219 	x = be32_to_cpu(rec->alloc.ar_startblock);
220 	x += be32_to_cpu(rec->alloc.ar_blockcount) - 1;
221 	key->alloc.ar_startblock = cpu_to_be32(x);
222 	key->alloc.ar_blockcount = 0;
223 }
224 
225 STATIC void
226 xfs_cntbt_init_high_key_from_rec(
227 	union xfs_btree_key	*key,
228 	union xfs_btree_rec	*rec)
229 {
230 	key->alloc.ar_blockcount = rec->alloc.ar_blockcount;
231 	key->alloc.ar_startblock = 0;
232 }
233 
234 STATIC void
235 xfs_allocbt_init_rec_from_cur(
236 	struct xfs_btree_cur	*cur,
237 	union xfs_btree_rec	*rec)
238 {
239 	rec->alloc.ar_startblock = cpu_to_be32(cur->bc_rec.a.ar_startblock);
240 	rec->alloc.ar_blockcount = cpu_to_be32(cur->bc_rec.a.ar_blockcount);
241 }
242 
243 STATIC void
244 xfs_allocbt_init_ptr_from_cur(
245 	struct xfs_btree_cur	*cur,
246 	union xfs_btree_ptr	*ptr)
247 {
248 	struct xfs_agf		*agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
249 
250 	ASSERT(cur->bc_private.a.agno == be32_to_cpu(agf->agf_seqno));
251 	ASSERT(agf->agf_roots[cur->bc_btnum] != 0);
252 
253 	ptr->s = agf->agf_roots[cur->bc_btnum];
254 }
255 
256 STATIC int64_t
257 xfs_bnobt_key_diff(
258 	struct xfs_btree_cur	*cur,
259 	union xfs_btree_key	*key)
260 {
261 	xfs_alloc_rec_incore_t	*rec = &cur->bc_rec.a;
262 	xfs_alloc_key_t		*kp = &key->alloc;
263 
264 	return (int64_t)be32_to_cpu(kp->ar_startblock) - rec->ar_startblock;
265 }
266 
267 STATIC int64_t
268 xfs_cntbt_key_diff(
269 	struct xfs_btree_cur	*cur,
270 	union xfs_btree_key	*key)
271 {
272 	xfs_alloc_rec_incore_t	*rec = &cur->bc_rec.a;
273 	xfs_alloc_key_t		*kp = &key->alloc;
274 	int64_t			diff;
275 
276 	diff = (int64_t)be32_to_cpu(kp->ar_blockcount) - rec->ar_blockcount;
277 	if (diff)
278 		return diff;
279 
280 	return (int64_t)be32_to_cpu(kp->ar_startblock) - rec->ar_startblock;
281 }
282 
283 STATIC int64_t
284 xfs_bnobt_diff_two_keys(
285 	struct xfs_btree_cur	*cur,
286 	union xfs_btree_key	*k1,
287 	union xfs_btree_key	*k2)
288 {
289 	return (int64_t)be32_to_cpu(k1->alloc.ar_startblock) -
290 			  be32_to_cpu(k2->alloc.ar_startblock);
291 }
292 
293 STATIC int64_t
294 xfs_cntbt_diff_two_keys(
295 	struct xfs_btree_cur	*cur,
296 	union xfs_btree_key	*k1,
297 	union xfs_btree_key	*k2)
298 {
299 	int64_t			diff;
300 
301 	diff =  be32_to_cpu(k1->alloc.ar_blockcount) -
302 		be32_to_cpu(k2->alloc.ar_blockcount);
303 	if (diff)
304 		return diff;
305 
306 	return  be32_to_cpu(k1->alloc.ar_startblock) -
307 		be32_to_cpu(k2->alloc.ar_startblock);
308 }
309 
310 static bool
311 xfs_allocbt_verify(
312 	struct xfs_buf		*bp)
313 {
314 	struct xfs_mount	*mp = bp->b_target->bt_mount;
315 	struct xfs_btree_block	*block = XFS_BUF_TO_BLOCK(bp);
316 	struct xfs_perag	*pag = bp->b_pag;
317 	unsigned int		level;
318 
319 	/*
320 	 * magic number and level verification
321 	 *
322 	 * During growfs operations, we can't verify the exact level or owner as
323 	 * the perag is not fully initialised and hence not attached to the
324 	 * buffer.  In this case, check against the maximum tree depth.
325 	 *
326 	 * Similarly, during log recovery we will have a perag structure
327 	 * attached, but the agf information will not yet have been initialised
328 	 * from the on disk AGF. Again, we can only check against maximum limits
329 	 * in this case.
330 	 */
331 	level = be16_to_cpu(block->bb_level);
332 	switch (block->bb_magic) {
333 	case cpu_to_be32(XFS_ABTB_CRC_MAGIC):
334 		if (!xfs_btree_sblock_v5hdr_verify(bp))
335 			return false;
336 		/* fall through */
337 	case cpu_to_be32(XFS_ABTB_MAGIC):
338 		if (pag && pag->pagf_init) {
339 			if (level >= pag->pagf_levels[XFS_BTNUM_BNOi])
340 				return false;
341 		} else if (level >= mp->m_ag_maxlevels)
342 			return false;
343 		break;
344 	case cpu_to_be32(XFS_ABTC_CRC_MAGIC):
345 		if (!xfs_btree_sblock_v5hdr_verify(bp))
346 			return false;
347 		/* fall through */
348 	case cpu_to_be32(XFS_ABTC_MAGIC):
349 		if (pag && pag->pagf_init) {
350 			if (level >= pag->pagf_levels[XFS_BTNUM_CNTi])
351 				return false;
352 		} else if (level >= mp->m_ag_maxlevels)
353 			return false;
354 		break;
355 	default:
356 		return false;
357 	}
358 
359 	return xfs_btree_sblock_verify(bp, mp->m_alloc_mxr[level != 0]);
360 }
361 
362 static void
363 xfs_allocbt_read_verify(
364 	struct xfs_buf	*bp)
365 {
366 	if (!xfs_btree_sblock_verify_crc(bp))
367 		xfs_buf_ioerror(bp, -EFSBADCRC);
368 	else if (!xfs_allocbt_verify(bp))
369 		xfs_buf_ioerror(bp, -EFSCORRUPTED);
370 
371 	if (bp->b_error) {
372 		trace_xfs_btree_corrupt(bp, _RET_IP_);
373 		xfs_verifier_error(bp);
374 	}
375 }
376 
377 static void
378 xfs_allocbt_write_verify(
379 	struct xfs_buf	*bp)
380 {
381 	if (!xfs_allocbt_verify(bp)) {
382 		trace_xfs_btree_corrupt(bp, _RET_IP_);
383 		xfs_buf_ioerror(bp, -EFSCORRUPTED);
384 		xfs_verifier_error(bp);
385 		return;
386 	}
387 	xfs_btree_sblock_calc_crc(bp);
388 
389 }
390 
391 const struct xfs_buf_ops xfs_allocbt_buf_ops = {
392 	.name = "xfs_allocbt",
393 	.verify_read = xfs_allocbt_read_verify,
394 	.verify_write = xfs_allocbt_write_verify,
395 };
396 
397 
398 STATIC int
399 xfs_bnobt_keys_inorder(
400 	struct xfs_btree_cur	*cur,
401 	union xfs_btree_key	*k1,
402 	union xfs_btree_key	*k2)
403 {
404 	return be32_to_cpu(k1->alloc.ar_startblock) <
405 	       be32_to_cpu(k2->alloc.ar_startblock);
406 }
407 
408 STATIC int
409 xfs_bnobt_recs_inorder(
410 	struct xfs_btree_cur	*cur,
411 	union xfs_btree_rec	*r1,
412 	union xfs_btree_rec	*r2)
413 {
414 	return be32_to_cpu(r1->alloc.ar_startblock) +
415 		be32_to_cpu(r1->alloc.ar_blockcount) <=
416 		be32_to_cpu(r2->alloc.ar_startblock);
417 }
418 
419 STATIC int
420 xfs_cntbt_keys_inorder(
421 	struct xfs_btree_cur	*cur,
422 	union xfs_btree_key	*k1,
423 	union xfs_btree_key	*k2)
424 {
425 	return be32_to_cpu(k1->alloc.ar_blockcount) <
426 		be32_to_cpu(k2->alloc.ar_blockcount) ||
427 		(k1->alloc.ar_blockcount == k2->alloc.ar_blockcount &&
428 		 be32_to_cpu(k1->alloc.ar_startblock) <
429 		 be32_to_cpu(k2->alloc.ar_startblock));
430 }
431 
432 STATIC int
433 xfs_cntbt_recs_inorder(
434 	struct xfs_btree_cur	*cur,
435 	union xfs_btree_rec	*r1,
436 	union xfs_btree_rec	*r2)
437 {
438 	return be32_to_cpu(r1->alloc.ar_blockcount) <
439 		be32_to_cpu(r2->alloc.ar_blockcount) ||
440 		(r1->alloc.ar_blockcount == r2->alloc.ar_blockcount &&
441 		 be32_to_cpu(r1->alloc.ar_startblock) <
442 		 be32_to_cpu(r2->alloc.ar_startblock));
443 }
444 
445 static const struct xfs_btree_ops xfs_bnobt_ops = {
446 	.rec_len		= sizeof(xfs_alloc_rec_t),
447 	.key_len		= sizeof(xfs_alloc_key_t),
448 
449 	.dup_cursor		= xfs_allocbt_dup_cursor,
450 	.set_root		= xfs_allocbt_set_root,
451 	.alloc_block		= xfs_allocbt_alloc_block,
452 	.free_block		= xfs_allocbt_free_block,
453 	.update_lastrec		= xfs_allocbt_update_lastrec,
454 	.get_minrecs		= xfs_allocbt_get_minrecs,
455 	.get_maxrecs		= xfs_allocbt_get_maxrecs,
456 	.init_key_from_rec	= xfs_allocbt_init_key_from_rec,
457 	.init_high_key_from_rec	= xfs_bnobt_init_high_key_from_rec,
458 	.init_rec_from_cur	= xfs_allocbt_init_rec_from_cur,
459 	.init_ptr_from_cur	= xfs_allocbt_init_ptr_from_cur,
460 	.key_diff		= xfs_bnobt_key_diff,
461 	.buf_ops		= &xfs_allocbt_buf_ops,
462 	.diff_two_keys		= xfs_bnobt_diff_two_keys,
463 	.keys_inorder		= xfs_bnobt_keys_inorder,
464 	.recs_inorder		= xfs_bnobt_recs_inorder,
465 };
466 
467 static const struct xfs_btree_ops xfs_cntbt_ops = {
468 	.rec_len		= sizeof(xfs_alloc_rec_t),
469 	.key_len		= sizeof(xfs_alloc_key_t),
470 
471 	.dup_cursor		= xfs_allocbt_dup_cursor,
472 	.set_root		= xfs_allocbt_set_root,
473 	.alloc_block		= xfs_allocbt_alloc_block,
474 	.free_block		= xfs_allocbt_free_block,
475 	.update_lastrec		= xfs_allocbt_update_lastrec,
476 	.get_minrecs		= xfs_allocbt_get_minrecs,
477 	.get_maxrecs		= xfs_allocbt_get_maxrecs,
478 	.init_key_from_rec	= xfs_allocbt_init_key_from_rec,
479 	.init_high_key_from_rec	= xfs_cntbt_init_high_key_from_rec,
480 	.init_rec_from_cur	= xfs_allocbt_init_rec_from_cur,
481 	.init_ptr_from_cur	= xfs_allocbt_init_ptr_from_cur,
482 	.key_diff		= xfs_cntbt_key_diff,
483 	.buf_ops		= &xfs_allocbt_buf_ops,
484 	.diff_two_keys		= xfs_cntbt_diff_two_keys,
485 	.keys_inorder		= xfs_cntbt_keys_inorder,
486 	.recs_inorder		= xfs_cntbt_recs_inorder,
487 };
488 
489 /*
490  * Allocate a new allocation btree cursor.
491  */
492 struct xfs_btree_cur *			/* new alloc btree cursor */
493 xfs_allocbt_init_cursor(
494 	struct xfs_mount	*mp,		/* file system mount point */
495 	struct xfs_trans	*tp,		/* transaction pointer */
496 	struct xfs_buf		*agbp,		/* buffer for agf structure */
497 	xfs_agnumber_t		agno,		/* allocation group number */
498 	xfs_btnum_t		btnum)		/* btree identifier */
499 {
500 	struct xfs_agf		*agf = XFS_BUF_TO_AGF(agbp);
501 	struct xfs_btree_cur	*cur;
502 
503 	ASSERT(btnum == XFS_BTNUM_BNO || btnum == XFS_BTNUM_CNT);
504 
505 	cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_NOFS);
506 
507 	cur->bc_tp = tp;
508 	cur->bc_mp = mp;
509 	cur->bc_btnum = btnum;
510 	cur->bc_blocklog = mp->m_sb.sb_blocklog;
511 
512 	if (btnum == XFS_BTNUM_CNT) {
513 		cur->bc_statoff = XFS_STATS_CALC_INDEX(xs_abtc_2);
514 		cur->bc_ops = &xfs_cntbt_ops;
515 		cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]);
516 		cur->bc_flags = XFS_BTREE_LASTREC_UPDATE;
517 	} else {
518 		cur->bc_statoff = XFS_STATS_CALC_INDEX(xs_abtb_2);
519 		cur->bc_ops = &xfs_bnobt_ops;
520 		cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]);
521 	}
522 
523 	cur->bc_private.a.agbp = agbp;
524 	cur->bc_private.a.agno = agno;
525 
526 	if (xfs_sb_version_hascrc(&mp->m_sb))
527 		cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
528 
529 	return cur;
530 }
531 
532 /*
533  * Calculate number of records in an alloc btree block.
534  */
535 int
536 xfs_allocbt_maxrecs(
537 	struct xfs_mount	*mp,
538 	int			blocklen,
539 	int			leaf)
540 {
541 	blocklen -= XFS_ALLOC_BLOCK_LEN(mp);
542 
543 	if (leaf)
544 		return blocklen / sizeof(xfs_alloc_rec_t);
545 	return blocklen / (sizeof(xfs_alloc_key_t) + sizeof(xfs_alloc_ptr_t));
546 }
547