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xfs: detect agfl count corruption and reset agfl
[thirdparty/xfsprogs-dev.git] / libxfs / xfs_rmap_btree.c
CommitLineData
b3a96b46
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1/*
2 * Copyright (c) 2014 Red Hat, 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 "libxfs_priv.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_bit.h"
25#include "xfs_sb.h"
26#include "xfs_mount.h"
27#include "xfs_defer.h"
28#include "xfs_inode.h"
29#include "xfs_trans.h"
30#include "xfs_alloc.h"
31#include "xfs_btree.h"
936ca687 32#include "xfs_rmap.h"
b3a96b46
DW
33#include "xfs_rmap_btree.h"
34#include "xfs_trace.h"
35#include "xfs_cksum.h"
02cc8b2a 36#include "xfs_ag_resv.h"
b3a96b46 37
936ca687
DW
38/*
39 * Reverse map btree.
40 *
41 * This is a per-ag tree used to track the owner(s) of a given extent. With
42 * reflink it is possible for there to be multiple owners, which is a departure
43 * from classic XFS. Owner records for data extents are inserted when the
44 * extent is mapped and removed when an extent is unmapped. Owner records for
45 * all other block types (i.e. metadata) are inserted when an extent is
46 * allocated and removed when an extent is freed. There can only be one owner
47 * of a metadata extent, usually an inode or some other metadata structure like
48 * an AG btree.
49 *
50 * The rmap btree is part of the free space management, so blocks for the tree
51 * are sourced from the agfl. Hence we need transaction reservation support for
52 * this tree so that the freelist is always large enough. This also impacts on
53 * the minimum space we need to leave free in the AG.
54 *
55 * The tree is ordered by [ag block, owner, offset]. This is a large key size,
56 * but it is the only way to enforce unique keys when a block can be owned by
57 * multiple files at any offset. There's no need to order/search by extent
58 * size for online updating/management of the tree. It is intended that most
59 * reverse lookups will be to find the owner(s) of a particular block, or to
60 * try to recover tree and file data from corrupt primary metadata.
61 */
62
b3a96b46
DW
63static struct xfs_btree_cur *
64xfs_rmapbt_dup_cursor(
65 struct xfs_btree_cur *cur)
66{
67 return xfs_rmapbt_init_cursor(cur->bc_mp, cur->bc_tp,
68 cur->bc_private.a.agbp, cur->bc_private.a.agno);
69}
70
936ca687
DW
71STATIC void
72xfs_rmapbt_set_root(
73 struct xfs_btree_cur *cur,
74 union xfs_btree_ptr *ptr,
75 int inc)
76{
77 struct xfs_buf *agbp = cur->bc_private.a.agbp;
78 struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
79 xfs_agnumber_t seqno = be32_to_cpu(agf->agf_seqno);
80 int btnum = cur->bc_btnum;
81 struct xfs_perag *pag = xfs_perag_get(cur->bc_mp, seqno);
82
83 ASSERT(ptr->s != 0);
84
85 agf->agf_roots[btnum] = ptr->s;
86 be32_add_cpu(&agf->agf_levels[btnum], inc);
87 pag->pagf_levels[btnum] += inc;
88 xfs_perag_put(pag);
89
90 xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_ROOTS | XFS_AGF_LEVELS);
91}
92
93STATIC int
94xfs_rmapbt_alloc_block(
95 struct xfs_btree_cur *cur,
96 union xfs_btree_ptr *start,
97 union xfs_btree_ptr *new,
98 int *stat)
99{
8511b71a
DW
100 struct xfs_buf *agbp = cur->bc_private.a.agbp;
101 struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
936ca687
DW
102 int error;
103 xfs_agblock_t bno;
104
936ca687
DW
105 /* Allocate the new block from the freelist. If we can't, give up. */
106 error = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_private.a.agbp,
107 &bno, 1);
97b3ffd0 108 if (error)
936ca687 109 return error;
936ca687
DW
110
111 trace_xfs_rmapbt_alloc_block(cur->bc_mp, cur->bc_private.a.agno,
112 bno, 1);
113 if (bno == NULLAGBLOCK) {
936ca687
DW
114 *stat = 0;
115 return 0;
116 }
117
118 xfs_extent_busy_reuse(cur->bc_mp, cur->bc_private.a.agno, bno, 1,
119 false);
120
121 xfs_trans_agbtree_delta(cur->bc_tp, 1);
122 new->s = cpu_to_be32(bno);
8511b71a
DW
123 be32_add_cpu(&agf->agf_rmap_blocks, 1);
124 xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_RMAP_BLOCKS);
936ca687 125
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BF
126 xfs_ag_resv_rmapbt_alloc(cur->bc_mp, cur->bc_private.a.agno);
127
936ca687
DW
128 *stat = 1;
129 return 0;
130}
131
132STATIC int
133xfs_rmapbt_free_block(
134 struct xfs_btree_cur *cur,
135 struct xfs_buf *bp)
136{
137 struct xfs_buf *agbp = cur->bc_private.a.agbp;
138 struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
139 xfs_agblock_t bno;
140 int error;
141
142 bno = xfs_daddr_to_agbno(cur->bc_mp, XFS_BUF_ADDR(bp));
143 trace_xfs_rmapbt_free_block(cur->bc_mp, cur->bc_private.a.agno,
144 bno, 1);
8511b71a
DW
145 be32_add_cpu(&agf->agf_rmap_blocks, -1);
146 xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_RMAP_BLOCKS);
936ca687
DW
147 error = xfs_alloc_put_freelist(cur->bc_tp, agbp, NULL, bno, 1);
148 if (error)
149 return error;
150
151 xfs_extent_busy_insert(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1,
152 XFS_EXTENT_BUSY_SKIP_DISCARD);
153 xfs_trans_agbtree_delta(cur->bc_tp, -1);
154
9760cac2
BF
155 xfs_ag_resv_rmapbt_free(cur->bc_mp, cur->bc_private.a.agno);
156
936ca687
DW
157 return 0;
158}
159
160STATIC int
161xfs_rmapbt_get_minrecs(
162 struct xfs_btree_cur *cur,
163 int level)
164{
165 return cur->bc_mp->m_rmap_mnr[level != 0];
166}
167
168STATIC int
169xfs_rmapbt_get_maxrecs(
170 struct xfs_btree_cur *cur,
171 int level)
172{
173 return cur->bc_mp->m_rmap_mxr[level != 0];
174}
175
176STATIC void
177xfs_rmapbt_init_key_from_rec(
178 union xfs_btree_key *key,
179 union xfs_btree_rec *rec)
180{
181 key->rmap.rm_startblock = rec->rmap.rm_startblock;
182 key->rmap.rm_owner = rec->rmap.rm_owner;
183 key->rmap.rm_offset = rec->rmap.rm_offset;
184}
185
634b234e
DW
186/*
187 * The high key for a reverse mapping record can be computed by shifting
188 * the startblock and offset to the highest value that would still map
189 * to that record. In practice this means that we add blockcount-1 to
190 * the startblock for all records, and if the record is for a data/attr
191 * fork mapping, we add blockcount-1 to the offset too.
192 */
193STATIC void
194xfs_rmapbt_init_high_key_from_rec(
195 union xfs_btree_key *key,
196 union xfs_btree_rec *rec)
197{
4a492e72 198 uint64_t off;
634b234e
DW
199 int adj;
200
201 adj = be32_to_cpu(rec->rmap.rm_blockcount) - 1;
202
203 key->rmap.rm_startblock = rec->rmap.rm_startblock;
204 be32_add_cpu(&key->rmap.rm_startblock, adj);
205 key->rmap.rm_owner = rec->rmap.rm_owner;
206 key->rmap.rm_offset = rec->rmap.rm_offset;
207 if (XFS_RMAP_NON_INODE_OWNER(be64_to_cpu(rec->rmap.rm_owner)) ||
208 XFS_RMAP_IS_BMBT_BLOCK(be64_to_cpu(rec->rmap.rm_offset)))
209 return;
210 off = be64_to_cpu(key->rmap.rm_offset);
211 off = (XFS_RMAP_OFF(off) + adj) | (off & ~XFS_RMAP_OFF_MASK);
212 key->rmap.rm_offset = cpu_to_be64(off);
213}
214
936ca687
DW
215STATIC void
216xfs_rmapbt_init_rec_from_cur(
217 struct xfs_btree_cur *cur,
218 union xfs_btree_rec *rec)
219{
220 rec->rmap.rm_startblock = cpu_to_be32(cur->bc_rec.r.rm_startblock);
221 rec->rmap.rm_blockcount = cpu_to_be32(cur->bc_rec.r.rm_blockcount);
222 rec->rmap.rm_owner = cpu_to_be64(cur->bc_rec.r.rm_owner);
223 rec->rmap.rm_offset = cpu_to_be64(
224 xfs_rmap_irec_offset_pack(&cur->bc_rec.r));
225}
226
227STATIC void
228xfs_rmapbt_init_ptr_from_cur(
229 struct xfs_btree_cur *cur,
230 union xfs_btree_ptr *ptr)
231{
232 struct xfs_agf *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
233
234 ASSERT(cur->bc_private.a.agno == be32_to_cpu(agf->agf_seqno));
235 ASSERT(agf->agf_roots[cur->bc_btnum] != 0);
236
237 ptr->s = agf->agf_roots[cur->bc_btnum];
238}
239
4a492e72 240STATIC int64_t
936ca687
DW
241xfs_rmapbt_key_diff(
242 struct xfs_btree_cur *cur,
243 union xfs_btree_key *key)
244{
245 struct xfs_rmap_irec *rec = &cur->bc_rec.r;
246 struct xfs_rmap_key *kp = &key->rmap;
247 __u64 x, y;
4a492e72 248 int64_t d;
936ca687 249
4a492e72 250 d = (int64_t)be32_to_cpu(kp->rm_startblock) - rec->rm_startblock;
936ca687
DW
251 if (d)
252 return d;
253
254 x = be64_to_cpu(kp->rm_owner);
255 y = rec->rm_owner;
256 if (x > y)
257 return 1;
258 else if (y > x)
259 return -1;
260
261 x = XFS_RMAP_OFF(be64_to_cpu(kp->rm_offset));
262 y = rec->rm_offset;
263 if (x > y)
264 return 1;
265 else if (y > x)
266 return -1;
267 return 0;
268}
269
4a492e72 270STATIC int64_t
634b234e
DW
271xfs_rmapbt_diff_two_keys(
272 struct xfs_btree_cur *cur,
273 union xfs_btree_key *k1,
274 union xfs_btree_key *k2)
275{
276 struct xfs_rmap_key *kp1 = &k1->rmap;
277 struct xfs_rmap_key *kp2 = &k2->rmap;
4a492e72 278 int64_t d;
634b234e
DW
279 __u64 x, y;
280
4a492e72 281 d = (int64_t)be32_to_cpu(kp1->rm_startblock) -
634b234e
DW
282 be32_to_cpu(kp2->rm_startblock);
283 if (d)
284 return d;
285
286 x = be64_to_cpu(kp1->rm_owner);
287 y = be64_to_cpu(kp2->rm_owner);
288 if (x > y)
289 return 1;
290 else if (y > x)
291 return -1;
292
293 x = XFS_RMAP_OFF(be64_to_cpu(kp1->rm_offset));
294 y = XFS_RMAP_OFF(be64_to_cpu(kp2->rm_offset));
295 if (x > y)
296 return 1;
297 else if (y > x)
298 return -1;
299 return 0;
300}
301
bc01119d 302static xfs_failaddr_t
b3a96b46
DW
303xfs_rmapbt_verify(
304 struct xfs_buf *bp)
305{
306 struct xfs_mount *mp = bp->b_target->bt_mount;
307 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
308 struct xfs_perag *pag = bp->b_pag;
bc01119d 309 xfs_failaddr_t fa;
b3a96b46
DW
310 unsigned int level;
311
312 /*
313 * magic number and level verification
314 *
315 * During growfs operations, we can't verify the exact level or owner as
316 * the perag is not fully initialised and hence not attached to the
317 * buffer. In this case, check against the maximum tree depth.
318 *
319 * Similarly, during log recovery we will have a perag structure
320 * attached, but the agf information will not yet have been initialised
321 * from the on disk AGF. Again, we can only check against maximum limits
322 * in this case.
323 */
324 if (block->bb_magic != cpu_to_be32(XFS_RMAP_CRC_MAGIC))
bc01119d 325 return __this_address;
b3a96b46
DW
326
327 if (!xfs_sb_version_hasrmapbt(&mp->m_sb))
bc01119d
DW
328 return __this_address;
329 fa = xfs_btree_sblock_v5hdr_verify(bp);
330 if (fa)
331 return fa;
b3a96b46
DW
332
333 level = be16_to_cpu(block->bb_level);
334 if (pag && pag->pagf_init) {
335 if (level >= pag->pagf_levels[XFS_BTNUM_RMAPi])
bc01119d 336 return __this_address;
b3a96b46 337 } else if (level >= mp->m_rmap_maxlevels)
bc01119d 338 return __this_address;
b3a96b46
DW
339
340 return xfs_btree_sblock_verify(bp, mp->m_rmap_mxr[level != 0]);
341}
342
343static void
344xfs_rmapbt_read_verify(
345 struct xfs_buf *bp)
346{
1e697959
DW
347 xfs_failaddr_t fa;
348
b3a96b46 349 if (!xfs_btree_sblock_verify_crc(bp))
1e697959
DW
350 xfs_verifier_error(bp, -EFSBADCRC, __this_address);
351 else {
352 fa = xfs_rmapbt_verify(bp);
353 if (fa)
354 xfs_verifier_error(bp, -EFSCORRUPTED, fa);
355 }
b3a96b46 356
7e6c95f1 357 if (bp->b_error)
b3a96b46 358 trace_xfs_btree_corrupt(bp, _RET_IP_);
b3a96b46
DW
359}
360
361static void
362xfs_rmapbt_write_verify(
363 struct xfs_buf *bp)
364{
1e697959
DW
365 xfs_failaddr_t fa;
366
367 fa = xfs_rmapbt_verify(bp);
368 if (fa) {
b3a96b46 369 trace_xfs_btree_corrupt(bp, _RET_IP_);
1e697959 370 xfs_verifier_error(bp, -EFSCORRUPTED, fa);
b3a96b46
DW
371 return;
372 }
373 xfs_btree_sblock_calc_crc(bp);
374
375}
376
377const struct xfs_buf_ops xfs_rmapbt_buf_ops = {
378 .name = "xfs_rmapbt",
379 .verify_read = xfs_rmapbt_read_verify,
380 .verify_write = xfs_rmapbt_write_verify,
95d9582b 381 .verify_struct = xfs_rmapbt_verify,
b3a96b46
DW
382};
383
936ca687
DW
384STATIC int
385xfs_rmapbt_keys_inorder(
386 struct xfs_btree_cur *cur,
387 union xfs_btree_key *k1,
388 union xfs_btree_key *k2)
389{
4a492e72
DW
390 uint32_t x;
391 uint32_t y;
392 uint64_t a;
393 uint64_t b;
936ca687
DW
394
395 x = be32_to_cpu(k1->rmap.rm_startblock);
396 y = be32_to_cpu(k2->rmap.rm_startblock);
397 if (x < y)
398 return 1;
399 else if (x > y)
400 return 0;
401 a = be64_to_cpu(k1->rmap.rm_owner);
402 b = be64_to_cpu(k2->rmap.rm_owner);
403 if (a < b)
404 return 1;
405 else if (a > b)
406 return 0;
407 a = XFS_RMAP_OFF(be64_to_cpu(k1->rmap.rm_offset));
408 b = XFS_RMAP_OFF(be64_to_cpu(k2->rmap.rm_offset));
409 if (a <= b)
410 return 1;
411 return 0;
412}
413
414STATIC int
415xfs_rmapbt_recs_inorder(
416 struct xfs_btree_cur *cur,
417 union xfs_btree_rec *r1,
418 union xfs_btree_rec *r2)
419{
4a492e72
DW
420 uint32_t x;
421 uint32_t y;
422 uint64_t a;
423 uint64_t b;
936ca687
DW
424
425 x = be32_to_cpu(r1->rmap.rm_startblock);
426 y = be32_to_cpu(r2->rmap.rm_startblock);
427 if (x < y)
428 return 1;
429 else if (x > y)
430 return 0;
431 a = be64_to_cpu(r1->rmap.rm_owner);
432 b = be64_to_cpu(r2->rmap.rm_owner);
433 if (a < b)
434 return 1;
435 else if (a > b)
436 return 0;
437 a = XFS_RMAP_OFF(be64_to_cpu(r1->rmap.rm_offset));
438 b = XFS_RMAP_OFF(be64_to_cpu(r2->rmap.rm_offset));
439 if (a <= b)
440 return 1;
441 return 0;
442}
936ca687 443
b3a96b46
DW
444static const struct xfs_btree_ops xfs_rmapbt_ops = {
445 .rec_len = sizeof(struct xfs_rmap_rec),
446 .key_len = 2 * sizeof(struct xfs_rmap_key),
447
448 .dup_cursor = xfs_rmapbt_dup_cursor,
936ca687
DW
449 .set_root = xfs_rmapbt_set_root,
450 .alloc_block = xfs_rmapbt_alloc_block,
451 .free_block = xfs_rmapbt_free_block,
452 .get_minrecs = xfs_rmapbt_get_minrecs,
453 .get_maxrecs = xfs_rmapbt_get_maxrecs,
454 .init_key_from_rec = xfs_rmapbt_init_key_from_rec,
634b234e 455 .init_high_key_from_rec = xfs_rmapbt_init_high_key_from_rec,
936ca687
DW
456 .init_rec_from_cur = xfs_rmapbt_init_rec_from_cur,
457 .init_ptr_from_cur = xfs_rmapbt_init_ptr_from_cur,
458 .key_diff = xfs_rmapbt_key_diff,
b3a96b46 459 .buf_ops = &xfs_rmapbt_buf_ops,
634b234e 460 .diff_two_keys = xfs_rmapbt_diff_two_keys,
936ca687
DW
461 .keys_inorder = xfs_rmapbt_keys_inorder,
462 .recs_inorder = xfs_rmapbt_recs_inorder,
b3a96b46
DW
463};
464
465/*
466 * Allocate a new allocation btree cursor.
467 */
468struct xfs_btree_cur *
469xfs_rmapbt_init_cursor(
470 struct xfs_mount *mp,
471 struct xfs_trans *tp,
472 struct xfs_buf *agbp,
473 xfs_agnumber_t agno)
474{
475 struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
476 struct xfs_btree_cur *cur;
477
478 cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_NOFS);
479 cur->bc_tp = tp;
480 cur->bc_mp = mp;
634b234e 481 /* Overlapping btree; 2 keys per pointer. */
b3a96b46 482 cur->bc_btnum = XFS_BTNUM_RMAP;
634b234e 483 cur->bc_flags = XFS_BTREE_CRC_BLOCKS | XFS_BTREE_OVERLAPPING;
b3a96b46
DW
484 cur->bc_blocklog = mp->m_sb.sb_blocklog;
485 cur->bc_ops = &xfs_rmapbt_ops;
486 cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAP]);
5d8acc46 487 cur->bc_statoff = XFS_STATS_CALC_INDEX(xs_rmap_2);
b3a96b46
DW
488
489 cur->bc_private.a.agbp = agbp;
490 cur->bc_private.a.agno = agno;
491
492 return cur;
493}
494
495/*
496 * Calculate number of records in an rmap btree block.
497 */
498int
499xfs_rmapbt_maxrecs(
500 struct xfs_mount *mp,
501 int blocklen,
502 int leaf)
503{
504 blocklen -= XFS_RMAP_BLOCK_LEN;
505
506 if (leaf)
507 return blocklen / sizeof(struct xfs_rmap_rec);
508 return blocklen /
634b234e 509 (2 * sizeof(struct xfs_rmap_key) + sizeof(xfs_rmap_ptr_t));
b3a96b46
DW
510}
511
512/* Compute the maximum height of an rmap btree. */
513void
514xfs_rmapbt_compute_maxlevels(
515 struct xfs_mount *mp)
516{
88ce0792
DW
517 /*
518 * On a non-reflink filesystem, the maximum number of rmap
519 * records is the number of blocks in the AG, hence the max
520 * rmapbt height is log_$maxrecs($agblocks). However, with
521 * reflink each AG block can have up to 2^32 (per the refcount
522 * record format) owners, which means that theoretically we
523 * could face up to 2^64 rmap records.
524 *
525 * That effectively means that the max rmapbt height must be
526 * XFS_BTREE_MAXLEVELS. "Fortunately" we'll run out of AG
527 * blocks to feed the rmapbt long before the rmapbt reaches
528 * maximum height. The reflink code uses ag_resv_critical to
529 * disallow reflinking when less than 10% of the per-AG metadata
530 * block reservation since the fallback is a regular file copy.
531 */
532 if (xfs_sb_version_hasreflink(&mp->m_sb))
533 mp->m_rmap_maxlevels = XFS_BTREE_MAXLEVELS;
534 else
535 mp->m_rmap_maxlevels = xfs_btree_compute_maxlevels(mp,
536 mp->m_rmap_mnr, mp->m_sb.sb_agblocks);
b3a96b46 537}
02cc8b2a
DW
538
539/* Calculate the refcount btree size for some records. */
540xfs_extlen_t
541xfs_rmapbt_calc_size(
542 struct xfs_mount *mp,
543 unsigned long long len)
544{
545 return xfs_btree_calc_size(mp, mp->m_rmap_mnr, len);
546}
547
548/*
549 * Calculate the maximum refcount btree size.
550 */
551xfs_extlen_t
552xfs_rmapbt_max_size(
f21c57ed
DW
553 struct xfs_mount *mp,
554 xfs_agblock_t agblocks)
02cc8b2a
DW
555{
556 /* Bail out if we're uninitialized, which can happen in mkfs. */
557 if (mp->m_rmap_mxr[0] == 0)
558 return 0;
559
f21c57ed 560 return xfs_rmapbt_calc_size(mp, agblocks);
02cc8b2a
DW
561}
562
563/*
564 * Figure out how many blocks to reserve and how many are used by this btree.
565 */
566int
567xfs_rmapbt_calc_reserves(
568 struct xfs_mount *mp,
569 xfs_agnumber_t agno,
570 xfs_extlen_t *ask,
571 xfs_extlen_t *used)
572{
573 struct xfs_buf *agbp;
574 struct xfs_agf *agf;
f21c57ed 575 xfs_agblock_t agblocks;
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576 xfs_extlen_t tree_len;
577 int error;
578
579 if (!xfs_sb_version_hasrmapbt(&mp->m_sb))
580 return 0;
581
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582 error = xfs_alloc_read_agf(mp, NULL, agno, 0, &agbp);
583 if (error)
584 return error;
585
586 agf = XFS_BUF_TO_AGF(agbp);
f21c57ed 587 agblocks = be32_to_cpu(agf->agf_length);
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588 tree_len = be32_to_cpu(agf->agf_rmap_blocks);
589 xfs_buf_relse(agbp);
590
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591 /* Reserve 1% of the AG or enough for 1 block per record. */
592 *ask += max(agblocks / 100, xfs_rmapbt_max_size(mp, agblocks));
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593 *used += tree_len;
594
595 return error;
596}