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1/*
2 * Copyright (c) 2000-2002,2005 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_bit.h"
25#include "xfs_sb.h"
26#include "xfs_mount.h"
27#include "xfs_inode.h"
28#include "xfs_btree.h"
29#include "xfs_ialloc.h"
30#include "xfs_ialloc_btree.h"
31#include "xfs_alloc.h"
32#include "xfs_rtalloc.h"
33#include "xfs_error.h"
34#include "xfs_bmap.h"
35#include "xfs_cksum.h"
36#include "xfs_trans.h"
37#include "xfs_buf_item.h"
38#include "xfs_icreate_item.h"
39#include "xfs_icache.h"
40#include "xfs_trace.h"
41#include "xfs_log.h"
42
43
44/*
45 * Allocation group level functions.
46 */
47static inline int
48xfs_ialloc_cluster_alignment(
49 struct xfs_mount *mp)
50{
51 if (xfs_sb_version_hasalign(&mp->m_sb) &&
52 mp->m_sb.sb_inoalignmt >=
53 XFS_B_TO_FSBT(mp, mp->m_inode_cluster_size))
54 return mp->m_sb.sb_inoalignmt;
55 return 1;
56}
57
58/*
59 * Lookup a record by ino in the btree given by cur.
60 */
61int /* error */
62xfs_inobt_lookup(
63 struct xfs_btree_cur *cur, /* btree cursor */
64 xfs_agino_t ino, /* starting inode of chunk */
65 xfs_lookup_t dir, /* <=, >=, == */
66 int *stat) /* success/failure */
67{
68 cur->bc_rec.i.ir_startino = ino;
69 cur->bc_rec.i.ir_holemask = 0;
70 cur->bc_rec.i.ir_count = 0;
71 cur->bc_rec.i.ir_freecount = 0;
72 cur->bc_rec.i.ir_free = 0;
73 return xfs_btree_lookup(cur, dir, stat);
74}
75
76/*
77 * Update the record referred to by cur to the value given.
78 * This either works (return 0) or gets an EFSCORRUPTED error.
79 */
80STATIC int /* error */
81xfs_inobt_update(
82 struct xfs_btree_cur *cur, /* btree cursor */
83 xfs_inobt_rec_incore_t *irec) /* btree record */
84{
85 union xfs_btree_rec rec;
86
87 rec.inobt.ir_startino = cpu_to_be32(irec->ir_startino);
88 if (xfs_sb_version_hassparseinodes(&cur->bc_mp->m_sb)) {
89 rec.inobt.ir_u.sp.ir_holemask = cpu_to_be16(irec->ir_holemask);
90 rec.inobt.ir_u.sp.ir_count = irec->ir_count;
91 rec.inobt.ir_u.sp.ir_freecount = irec->ir_freecount;
92 } else {
93 /* ir_holemask/ir_count not supported on-disk */
94 rec.inobt.ir_u.f.ir_freecount = cpu_to_be32(irec->ir_freecount);
95 }
96 rec.inobt.ir_free = cpu_to_be64(irec->ir_free);
97 return xfs_btree_update(cur, &rec);
98}
99
100/*
101 * Get the data from the pointed-to record.
102 */
103int /* error */
104xfs_inobt_get_rec(
105 struct xfs_btree_cur *cur, /* btree cursor */
106 xfs_inobt_rec_incore_t *irec, /* btree record */
107 int *stat) /* output: success/failure */
108{
109 union xfs_btree_rec *rec;
110 int error;
111
112 error = xfs_btree_get_rec(cur, &rec, stat);
113 if (error || *stat == 0)
114 return error;
115
116 irec->ir_startino = be32_to_cpu(rec->inobt.ir_startino);
117 if (xfs_sb_version_hassparseinodes(&cur->bc_mp->m_sb)) {
118 irec->ir_holemask = be16_to_cpu(rec->inobt.ir_u.sp.ir_holemask);
119 irec->ir_count = rec->inobt.ir_u.sp.ir_count;
120 irec->ir_freecount = rec->inobt.ir_u.sp.ir_freecount;
121 } else {
122 /*
123 * ir_holemask/ir_count not supported on-disk. Fill in hardcoded
124 * values for full inode chunks.
125 */
126 irec->ir_holemask = XFS_INOBT_HOLEMASK_FULL;
127 irec->ir_count = XFS_INODES_PER_CHUNK;
128 irec->ir_freecount =
129 be32_to_cpu(rec->inobt.ir_u.f.ir_freecount);
130 }
131 irec->ir_free = be64_to_cpu(rec->inobt.ir_free);
132
133 return 0;
134}
135
136/*
137 * Insert a single inobt record. Cursor must already point to desired location.
138 */
139STATIC int
140xfs_inobt_insert_rec(
141 struct xfs_btree_cur *cur,
142 __uint16_t holemask,
143 __uint8_t count,
144 __int32_t freecount,
145 xfs_inofree_t free,
146 int *stat)
147{
148 cur->bc_rec.i.ir_holemask = holemask;
149 cur->bc_rec.i.ir_count = count;
150 cur->bc_rec.i.ir_freecount = freecount;
151 cur->bc_rec.i.ir_free = free;
152 return xfs_btree_insert(cur, stat);
153}
154
155/*
156 * Insert records describing a newly allocated inode chunk into the inobt.
157 */
158STATIC int
159xfs_inobt_insert(
160 struct xfs_mount *mp,
161 struct xfs_trans *tp,
162 struct xfs_buf *agbp,
163 xfs_agino_t newino,
164 xfs_agino_t newlen,
165 xfs_btnum_t btnum)
166{
167 struct xfs_btree_cur *cur;
168 struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
169 xfs_agnumber_t agno = be32_to_cpu(agi->agi_seqno);
170 xfs_agino_t thisino;
171 int i;
172 int error;
173
174 cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, btnum);
175
176 for (thisino = newino;
177 thisino < newino + newlen;
178 thisino += XFS_INODES_PER_CHUNK) {
179 error = xfs_inobt_lookup(cur, thisino, XFS_LOOKUP_EQ, &i);
180 if (error) {
181 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
182 return error;
183 }
184 ASSERT(i == 0);
185
186 error = xfs_inobt_insert_rec(cur, XFS_INOBT_HOLEMASK_FULL,
187 XFS_INODES_PER_CHUNK,
188 XFS_INODES_PER_CHUNK,
189 XFS_INOBT_ALL_FREE, &i);
190 if (error) {
191 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
192 return error;
193 }
194 ASSERT(i == 1);
195 }
196
197 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
198
199 return 0;
200}
201
202/*
203 * Verify that the number of free inodes in the AGI is correct.
204 */
205#ifdef DEBUG
206STATIC int
207xfs_check_agi_freecount(
208 struct xfs_btree_cur *cur,
209 struct xfs_agi *agi)
210{
211 if (cur->bc_nlevels == 1) {
212 xfs_inobt_rec_incore_t rec;
213 int freecount = 0;
214 int error;
215 int i;
216
217 error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
218 if (error)
219 return error;
220
221 do {
222 error = xfs_inobt_get_rec(cur, &rec, &i);
223 if (error)
224 return error;
225
226 if (i) {
227 freecount += rec.ir_freecount;
228 error = xfs_btree_increment(cur, 0, &i);
229 if (error)
230 return error;
231 }
232 } while (i == 1);
233
234 if (!XFS_FORCED_SHUTDOWN(cur->bc_mp))
235 ASSERT(freecount == be32_to_cpu(agi->agi_freecount));
236 }
237 return 0;
238}
239#else
240#define xfs_check_agi_freecount(cur, agi) 0
241#endif
242
243/*
244 * Initialise a new set of inodes. When called without a transaction context
245 * (e.g. from recovery) we initiate a delayed write of the inode buffers rather
246 * than logging them (which in a transaction context puts them into the AIL
247 * for writeback rather than the xfsbufd queue).
248 */
249int
250xfs_ialloc_inode_init(
251 struct xfs_mount *mp,
252 struct xfs_trans *tp,
253 struct list_head *buffer_list,
254 int icount,
255 xfs_agnumber_t agno,
256 xfs_agblock_t agbno,
257 xfs_agblock_t length,
258 unsigned int gen)
259{
260 struct xfs_buf *fbuf;
261 struct xfs_dinode *free;
262 int nbufs, blks_per_cluster, inodes_per_cluster;
263 int version;
264 int i, j;
265 xfs_daddr_t d;
266 xfs_ino_t ino = 0;
267
268 /*
269 * Loop over the new block(s), filling in the inodes. For small block
270 * sizes, manipulate the inodes in buffers which are multiples of the
271 * blocks size.
272 */
273 blks_per_cluster = xfs_icluster_size_fsb(mp);
274 inodes_per_cluster = blks_per_cluster << mp->m_sb.sb_inopblog;
275 nbufs = length / blks_per_cluster;
276
277 /*
278 * Figure out what version number to use in the inodes we create. If
279 * the superblock version has caught up to the one that supports the new
280 * inode format, then use the new inode version. Otherwise use the old
281 * version so that old kernels will continue to be able to use the file
282 * system.
283 *
284 * For v3 inodes, we also need to write the inode number into the inode,
285 * so calculate the first inode number of the chunk here as
286 * XFS_OFFBNO_TO_AGINO() only works within a filesystem block, not
287 * across multiple filesystem blocks (such as a cluster) and so cannot
288 * be used in the cluster buffer loop below.
289 *
290 * Further, because we are writing the inode directly into the buffer
291 * and calculating a CRC on the entire inode, we have ot log the entire
292 * inode so that the entire range the CRC covers is present in the log.
293 * That means for v3 inode we log the entire buffer rather than just the
294 * inode cores.
295 */
296 if (xfs_sb_version_hascrc(&mp->m_sb)) {
297 version = 3;
298 ino = XFS_AGINO_TO_INO(mp, agno,
299 XFS_OFFBNO_TO_AGINO(mp, agbno, 0));
300
301 /*
302 * log the initialisation that is about to take place as an
303 * logical operation. This means the transaction does not
304 * need to log the physical changes to the inode buffers as log
305 * recovery will know what initialisation is actually needed.
306 * Hence we only need to log the buffers as "ordered" buffers so
307 * they track in the AIL as if they were physically logged.
308 */
309 if (tp)
310 xfs_icreate_log(tp, agno, agbno, icount,
311 mp->m_sb.sb_inodesize, length, gen);
312 } else
313 version = 2;
314
315 for (j = 0; j < nbufs; j++) {
316 /*
317 * Get the block.
318 */
319 d = XFS_AGB_TO_DADDR(mp, agno, agbno + (j * blks_per_cluster));
320 fbuf = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
321 mp->m_bsize * blks_per_cluster,
322 XBF_UNMAPPED);
323 if (!fbuf)
324 return -ENOMEM;
325
326 /* Initialize the inode buffers and log them appropriately. */
327 fbuf->b_ops = &xfs_inode_buf_ops;
328 xfs_buf_zero(fbuf, 0, BBTOB(fbuf->b_length));
329 for (i = 0; i < inodes_per_cluster; i++) {
330 int ioffset = i << mp->m_sb.sb_inodelog;
331 uint isize = xfs_dinode_size(version);
332
333 free = xfs_make_iptr(mp, fbuf, i);
334 free->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
335 free->di_version = version;
336 free->di_gen = cpu_to_be32(gen);
337 free->di_next_unlinked = cpu_to_be32(NULLAGINO);
338
339 if (version == 3) {
340 free->di_ino = cpu_to_be64(ino);
341 ino++;
342 uuid_copy(&free->di_uuid,
343 &mp->m_sb.sb_meta_uuid);
344 xfs_dinode_calc_crc(mp, free);
345 } else if (tp) {
346 /* just log the inode core */
347 xfs_trans_log_buf(tp, fbuf, ioffset,
348 ioffset + isize - 1);
349 }
350 }
351
352 if (tp) {
353 /*
354 * Mark the buffer as an inode allocation buffer so it
355 * sticks in AIL at the point of this allocation
356 * transaction. This ensures the they are on disk before
357 * the tail of the log can be moved past this
358 * transaction (i.e. by preventing relogging from moving
359 * it forward in the log).
360 */
361 xfs_trans_inode_alloc_buf(tp, fbuf);
362 if (version == 3) {
363 /*
364 * Mark the buffer as ordered so that they are
365 * not physically logged in the transaction but
366 * still tracked in the AIL as part of the
367 * transaction and pin the log appropriately.
368 */
369 xfs_trans_ordered_buf(tp, fbuf);
370 xfs_trans_log_buf(tp, fbuf, 0,
371 BBTOB(fbuf->b_length) - 1);
372 }
373 } else {
374 fbuf->b_flags |= XBF_DONE;
375 xfs_buf_delwri_queue(fbuf, buffer_list);
376 xfs_buf_relse(fbuf);
377 }
378 }
379 return 0;
380}
381
382/*
383 * Align startino and allocmask for a recently allocated sparse chunk such that
384 * they are fit for insertion (or merge) into the on-disk inode btrees.
385 *
386 * Background:
387 *
388 * When enabled, sparse inode support increases the inode alignment from cluster
389 * size to inode chunk size. This means that the minimum range between two
390 * non-adjacent inode records in the inobt is large enough for a full inode
391 * record. This allows for cluster sized, cluster aligned block allocation
392 * without need to worry about whether the resulting inode record overlaps with
393 * another record in the tree. Without this basic rule, we would have to deal
394 * with the consequences of overlap by potentially undoing recent allocations in
395 * the inode allocation codepath.
396 *
397 * Because of this alignment rule (which is enforced on mount), there are two
398 * inobt possibilities for newly allocated sparse chunks. One is that the
399 * aligned inode record for the chunk covers a range of inodes not already
400 * covered in the inobt (i.e., it is safe to insert a new sparse record). The
401 * other is that a record already exists at the aligned startino that considers
402 * the newly allocated range as sparse. In the latter case, record content is
403 * merged in hope that sparse inode chunks fill to full chunks over time.
404 */
405STATIC void
406xfs_align_sparse_ino(
407 struct xfs_mount *mp,
408 xfs_agino_t *startino,
409 uint16_t *allocmask)
410{
411 xfs_agblock_t agbno;
412 xfs_agblock_t mod;
413 int offset;
414
415 agbno = XFS_AGINO_TO_AGBNO(mp, *startino);
416 mod = agbno % mp->m_sb.sb_inoalignmt;
417 if (!mod)
418 return;
419
420 /* calculate the inode offset and align startino */
421 offset = mod << mp->m_sb.sb_inopblog;
422 *startino -= offset;
423
424 /*
425 * Since startino has been aligned down, left shift allocmask such that
426 * it continues to represent the same physical inodes relative to the
427 * new startino.
428 */
429 *allocmask <<= offset / XFS_INODES_PER_HOLEMASK_BIT;
430}
431
432/*
433 * Determine whether the source inode record can merge into the target. Both
434 * records must be sparse, the inode ranges must match and there must be no
435 * allocation overlap between the records.
436 */
437STATIC bool
438__xfs_inobt_can_merge(
439 struct xfs_inobt_rec_incore *trec, /* tgt record */
440 struct xfs_inobt_rec_incore *srec) /* src record */
441{
442 uint64_t talloc;
443 uint64_t salloc;
444
445 /* records must cover the same inode range */
446 if (trec->ir_startino != srec->ir_startino)
447 return false;
448
449 /* both records must be sparse */
450 if (!xfs_inobt_issparse(trec->ir_holemask) ||
451 !xfs_inobt_issparse(srec->ir_holemask))
452 return false;
453
454 /* both records must track some inodes */
455 if (!trec->ir_count || !srec->ir_count)
456 return false;
457
458 /* can't exceed capacity of a full record */
459 if (trec->ir_count + srec->ir_count > XFS_INODES_PER_CHUNK)
460 return false;
461
462 /* verify there is no allocation overlap */
463 talloc = xfs_inobt_irec_to_allocmask(trec);
464 salloc = xfs_inobt_irec_to_allocmask(srec);
465 if (talloc & salloc)
466 return false;
467
468 return true;
469}
470
471/*
472 * Merge the source inode record into the target. The caller must call
473 * __xfs_inobt_can_merge() to ensure the merge is valid.
474 */
475STATIC void
476__xfs_inobt_rec_merge(
477 struct xfs_inobt_rec_incore *trec, /* target */
478 struct xfs_inobt_rec_incore *srec) /* src */
479{
480 ASSERT(trec->ir_startino == srec->ir_startino);
481
482 /* combine the counts */
483 trec->ir_count += srec->ir_count;
484 trec->ir_freecount += srec->ir_freecount;
485
486 /*
487 * Merge the holemask and free mask. For both fields, 0 bits refer to
488 * allocated inodes. We combine the allocated ranges with bitwise AND.
489 */
490 trec->ir_holemask &= srec->ir_holemask;
491 trec->ir_free &= srec->ir_free;
492}
493
494/*
495 * Insert a new sparse inode chunk into the associated inode btree. The inode
496 * record for the sparse chunk is pre-aligned to a startino that should match
497 * any pre-existing sparse inode record in the tree. This allows sparse chunks
498 * to fill over time.
499 *
500 * This function supports two modes of handling preexisting records depending on
501 * the merge flag. If merge is true, the provided record is merged with the
502 * existing record and updated in place. The merged record is returned in nrec.
503 * If merge is false, an existing record is replaced with the provided record.
504 * If no preexisting record exists, the provided record is always inserted.
505 *
506 * It is considered corruption if a merge is requested and not possible. Given
507 * the sparse inode alignment constraints, this should never happen.
508 */
509STATIC int
510xfs_inobt_insert_sprec(
511 struct xfs_mount *mp,
512 struct xfs_trans *tp,
513 struct xfs_buf *agbp,
514 int btnum,
515 struct xfs_inobt_rec_incore *nrec, /* in/out: new/merged rec. */
516 bool merge) /* merge or replace */
517{
518 struct xfs_btree_cur *cur;
519 struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
520 xfs_agnumber_t agno = be32_to_cpu(agi->agi_seqno);
521 int error;
522 int i;
523 struct xfs_inobt_rec_incore rec;
524
525 cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, btnum);
526
527 /* the new record is pre-aligned so we know where to look */
528 error = xfs_inobt_lookup(cur, nrec->ir_startino, XFS_LOOKUP_EQ, &i);
529 if (error)
530 goto error;
531 /* if nothing there, insert a new record and return */
532 if (i == 0) {
533 error = xfs_inobt_insert_rec(cur, nrec->ir_holemask,
534 nrec->ir_count, nrec->ir_freecount,
535 nrec->ir_free, &i);
536 if (error)
537 goto error;
538 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error);
539
540 goto out;
541 }
542
543 /*
544 * A record exists at this startino. Merge or replace the record
545 * depending on what we've been asked to do.
546 */
547 if (merge) {
548 error = xfs_inobt_get_rec(cur, &rec, &i);
549 if (error)
550 goto error;
551 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error);
552 XFS_WANT_CORRUPTED_GOTO(mp,
553 rec.ir_startino == nrec->ir_startino,
554 error);
555
556 /*
557 * This should never fail. If we have coexisting records that
558 * cannot merge, something is seriously wrong.
559 */
560 XFS_WANT_CORRUPTED_GOTO(mp, __xfs_inobt_can_merge(nrec, &rec),
561 error);
562
563 trace_xfs_irec_merge_pre(mp, agno, rec.ir_startino,
564 rec.ir_holemask, nrec->ir_startino,
565 nrec->ir_holemask);
566
567 /* merge to nrec to output the updated record */
568 __xfs_inobt_rec_merge(nrec, &rec);
569
570 trace_xfs_irec_merge_post(mp, agno, nrec->ir_startino,
571 nrec->ir_holemask);
572
573 error = xfs_inobt_rec_check_count(mp, nrec);
574 if (error)
575 goto error;
576 }
577
578 error = xfs_inobt_update(cur, nrec);
579 if (error)
580 goto error;
581
582out:
583 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
584 return 0;
585error:
586 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
587 return error;
588}
589
590/*
591 * Allocate new inodes in the allocation group specified by agbp.
592 * Return 0 for success, else error code.
593 */
594STATIC int /* error code or 0 */
595xfs_ialloc_ag_alloc(
596 xfs_trans_t *tp, /* transaction pointer */
597 xfs_buf_t *agbp, /* alloc group buffer */
598 int *alloc)
599{
600 xfs_agi_t *agi; /* allocation group header */
601 xfs_alloc_arg_t args; /* allocation argument structure */
602 xfs_agnumber_t agno;
603 int error;
604 xfs_agino_t newino; /* new first inode's number */
605 xfs_agino_t newlen; /* new number of inodes */
606 int isaligned = 0; /* inode allocation at stripe unit */
607 /* boundary */
608 uint16_t allocmask = (uint16_t) -1; /* init. to full chunk */
609 struct xfs_inobt_rec_incore rec;
610 struct xfs_perag *pag;
611 int do_sparse = 0;
612
613 memset(&args, 0, sizeof(args));
614 args.tp = tp;
615 args.mp = tp->t_mountp;
616 args.fsbno = NULLFSBLOCK;
617
618#ifdef DEBUG
619 /* randomly do sparse inode allocations */
620 if (xfs_sb_version_hassparseinodes(&tp->t_mountp->m_sb) &&
621 args.mp->m_ialloc_min_blks < args.mp->m_ialloc_blks)
622 do_sparse = prandom_u32() & 1;
623#endif
624
625 /*
626 * Locking will ensure that we don't have two callers in here
627 * at one time.
628 */
629 newlen = args.mp->m_ialloc_inos;
630 if (args.mp->m_maxicount &&
631 percpu_counter_read_positive(&args.mp->m_icount) + newlen >
632 args.mp->m_maxicount)
633 return -ENOSPC;
634 args.minlen = args.maxlen = args.mp->m_ialloc_blks;
635 /*
636 * First try to allocate inodes contiguous with the last-allocated
637 * chunk of inodes. If the filesystem is striped, this will fill
638 * an entire stripe unit with inodes.
639 */
640 agi = XFS_BUF_TO_AGI(agbp);
641 newino = be32_to_cpu(agi->agi_newino);
642 agno = be32_to_cpu(agi->agi_seqno);
643 args.agbno = XFS_AGINO_TO_AGBNO(args.mp, newino) +
644 args.mp->m_ialloc_blks;
645 if (do_sparse)
646 goto sparse_alloc;
647 if (likely(newino != NULLAGINO &&
648 (args.agbno < be32_to_cpu(agi->agi_length)))) {
649 args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
650 args.type = XFS_ALLOCTYPE_THIS_BNO;
651 args.prod = 1;
652
653 /*
654 * We need to take into account alignment here to ensure that
655 * we don't modify the free list if we fail to have an exact
656 * block. If we don't have an exact match, and every oher
657 * attempt allocation attempt fails, we'll end up cancelling
658 * a dirty transaction and shutting down.
659 *
660 * For an exact allocation, alignment must be 1,
661 * however we need to take cluster alignment into account when
662 * fixing up the freelist. Use the minalignslop field to
663 * indicate that extra blocks might be required for alignment,
664 * but not to use them in the actual exact allocation.
665 */
666 args.alignment = 1;
667 args.minalignslop = xfs_ialloc_cluster_alignment(args.mp) - 1;
668
669 /* Allow space for the inode btree to split. */
670 args.minleft = args.mp->m_in_maxlevels - 1;
671 if ((error = xfs_alloc_vextent(&args)))
672 return error;
673
674 /*
675 * This request might have dirtied the transaction if the AG can
676 * satisfy the request, but the exact block was not available.
677 * If the allocation did fail, subsequent requests will relax
678 * the exact agbno requirement and increase the alignment
679 * instead. It is critical that the total size of the request
680 * (len + alignment + slop) does not increase from this point
681 * on, so reset minalignslop to ensure it is not included in
682 * subsequent requests.
683 */
684 args.minalignslop = 0;
685 }
686
687 if (unlikely(args.fsbno == NULLFSBLOCK)) {
688 /*
689 * Set the alignment for the allocation.
690 * If stripe alignment is turned on then align at stripe unit
691 * boundary.
692 * If the cluster size is smaller than a filesystem block
693 * then we're doing I/O for inodes in filesystem block size
694 * pieces, so don't need alignment anyway.
695 */
696 isaligned = 0;
697 if (args.mp->m_sinoalign) {
698 ASSERT(!(args.mp->m_flags & XFS_MOUNT_NOALIGN));
699 args.alignment = args.mp->m_dalign;
700 isaligned = 1;
701 } else
702 args.alignment = xfs_ialloc_cluster_alignment(args.mp);
703 /*
704 * Need to figure out where to allocate the inode blocks.
705 * Ideally they should be spaced out through the a.g.
706 * For now, just allocate blocks up front.
707 */
708 args.agbno = be32_to_cpu(agi->agi_root);
709 args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
710 /*
711 * Allocate a fixed-size extent of inodes.
712 */
713 args.type = XFS_ALLOCTYPE_NEAR_BNO;
714 args.prod = 1;
715 /*
716 * Allow space for the inode btree to split.
717 */
718 args.minleft = args.mp->m_in_maxlevels - 1;
719 if ((error = xfs_alloc_vextent(&args)))
720 return error;
721 }
722
723 /*
724 * If stripe alignment is turned on, then try again with cluster
725 * alignment.
726 */
727 if (isaligned && args.fsbno == NULLFSBLOCK) {
728 args.type = XFS_ALLOCTYPE_NEAR_BNO;
729 args.agbno = be32_to_cpu(agi->agi_root);
730 args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
731 args.alignment = xfs_ialloc_cluster_alignment(args.mp);
732 if ((error = xfs_alloc_vextent(&args)))
733 return error;
734 }
735
736 /*
737 * Finally, try a sparse allocation if the filesystem supports it and
738 * the sparse allocation length is smaller than a full chunk.
739 */
740 if (xfs_sb_version_hassparseinodes(&args.mp->m_sb) &&
741 args.mp->m_ialloc_min_blks < args.mp->m_ialloc_blks &&
742 args.fsbno == NULLFSBLOCK) {
743sparse_alloc:
744 args.type = XFS_ALLOCTYPE_NEAR_BNO;
745 args.agbno = be32_to_cpu(agi->agi_root);
746 args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
747 args.alignment = args.mp->m_sb.sb_spino_align;
748 args.prod = 1;
749
750 args.minlen = args.mp->m_ialloc_min_blks;
751 args.maxlen = args.minlen;
752
753 /*
754 * The inode record will be aligned to full chunk size. We must
755 * prevent sparse allocation from AG boundaries that result in
756 * invalid inode records, such as records that start at agbno 0
757 * or extend beyond the AG.
758 *
759 * Set min agbno to the first aligned, non-zero agbno and max to
760 * the last aligned agbno that is at least one full chunk from
761 * the end of the AG.
762 */
763 args.min_agbno = args.mp->m_sb.sb_inoalignmt;
764 args.max_agbno = round_down(args.mp->m_sb.sb_agblocks,
765 args.mp->m_sb.sb_inoalignmt) -
766 args.mp->m_ialloc_blks;
767
768 error = xfs_alloc_vextent(&args);
769 if (error)
770 return error;
771
772 newlen = args.len << args.mp->m_sb.sb_inopblog;
773 ASSERT(newlen <= XFS_INODES_PER_CHUNK);
774 allocmask = (1 << (newlen / XFS_INODES_PER_HOLEMASK_BIT)) - 1;
775 }
776
777 if (args.fsbno == NULLFSBLOCK) {
778 *alloc = 0;
779 return 0;
780 }
781 ASSERT(args.len == args.minlen);
782
783 /*
784 * Stamp and write the inode buffers.
785 *
786 * Seed the new inode cluster with a random generation number. This
787 * prevents short-term reuse of generation numbers if a chunk is
788 * freed and then immediately reallocated. We use random numbers
789 * rather than a linear progression to prevent the next generation
790 * number from being easily guessable.
791 */
792 error = xfs_ialloc_inode_init(args.mp, tp, NULL, newlen, agno,
793 args.agbno, args.len, prandom_u32());
794
795 if (error)
796 return error;
797 /*
798 * Convert the results.
799 */
800 newino = XFS_OFFBNO_TO_AGINO(args.mp, args.agbno, 0);
801
802 if (xfs_inobt_issparse(~allocmask)) {
803 /*
804 * We've allocated a sparse chunk. Align the startino and mask.
805 */
806 xfs_align_sparse_ino(args.mp, &newino, &allocmask);
807
808 rec.ir_startino = newino;
809 rec.ir_holemask = ~allocmask;
810 rec.ir_count = newlen;
811 rec.ir_freecount = newlen;
812 rec.ir_free = XFS_INOBT_ALL_FREE;
813
814 /*
815 * Insert the sparse record into the inobt and allow for a merge
816 * if necessary. If a merge does occur, rec is updated to the
817 * merged record.
818 */
819 error = xfs_inobt_insert_sprec(args.mp, tp, agbp, XFS_BTNUM_INO,
820 &rec, true);
821 if (error == -EFSCORRUPTED) {
822 xfs_alert(args.mp,
823 "invalid sparse inode record: ino 0x%llx holemask 0x%x count %u",
824 XFS_AGINO_TO_INO(args.mp, agno,
825 rec.ir_startino),
826 rec.ir_holemask, rec.ir_count);
827 xfs_force_shutdown(args.mp, SHUTDOWN_CORRUPT_INCORE);
828 }
829 if (error)
830 return error;
831
832 /*
833 * We can't merge the part we've just allocated as for the inobt
834 * due to finobt semantics. The original record may or may not
835 * exist independent of whether physical inodes exist in this
836 * sparse chunk.
837 *
838 * We must update the finobt record based on the inobt record.
839 * rec contains the fully merged and up to date inobt record
840 * from the previous call. Set merge false to replace any
841 * existing record with this one.
842 */
843 if (xfs_sb_version_hasfinobt(&args.mp->m_sb)) {
844 error = xfs_inobt_insert_sprec(args.mp, tp, agbp,
845 XFS_BTNUM_FINO, &rec,
846 false);
847 if (error)
848 return error;
849 }
850 } else {
851 /* full chunk - insert new records to both btrees */
852 error = xfs_inobt_insert(args.mp, tp, agbp, newino, newlen,
853 XFS_BTNUM_INO);
854 if (error)
855 return error;
856
857 if (xfs_sb_version_hasfinobt(&args.mp->m_sb)) {
858 error = xfs_inobt_insert(args.mp, tp, agbp, newino,
859 newlen, XFS_BTNUM_FINO);
860 if (error)
861 return error;
862 }
863 }
864
865 /*
866 * Update AGI counts and newino.
867 */
868 be32_add_cpu(&agi->agi_count, newlen);
869 be32_add_cpu(&agi->agi_freecount, newlen);
870 pag = xfs_perag_get(args.mp, agno);
871 pag->pagi_freecount += newlen;
872 xfs_perag_put(pag);
873 agi->agi_newino = cpu_to_be32(newino);
874
875 /*
876 * Log allocation group header fields
877 */
878 xfs_ialloc_log_agi(tp, agbp,
879 XFS_AGI_COUNT | XFS_AGI_FREECOUNT | XFS_AGI_NEWINO);
880 /*
881 * Modify/log superblock values for inode count and inode free count.
882 */
883 xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, (long)newlen);
884 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, (long)newlen);
885 *alloc = 1;
886 return 0;
887}
888
889STATIC xfs_agnumber_t
890xfs_ialloc_next_ag(
891 xfs_mount_t *mp)
892{
893 xfs_agnumber_t agno;
894
895 spin_lock(&mp->m_agirotor_lock);
896 agno = mp->m_agirotor;
897 if (++mp->m_agirotor >= mp->m_maxagi)
898 mp->m_agirotor = 0;
899 spin_unlock(&mp->m_agirotor_lock);
900
901 return agno;
902}
903
904/*
905 * Select an allocation group to look for a free inode in, based on the parent
906 * inode and the mode. Return the allocation group buffer.
907 */
908STATIC xfs_agnumber_t
909xfs_ialloc_ag_select(
910 xfs_trans_t *tp, /* transaction pointer */
911 xfs_ino_t parent, /* parent directory inode number */
912 umode_t mode, /* bits set to indicate file type */
913 int okalloc) /* ok to allocate more space */
914{
915 xfs_agnumber_t agcount; /* number of ag's in the filesystem */
916 xfs_agnumber_t agno; /* current ag number */
917 int flags; /* alloc buffer locking flags */
918 xfs_extlen_t ineed; /* blocks needed for inode allocation */
919 xfs_extlen_t longest = 0; /* longest extent available */
920 xfs_mount_t *mp; /* mount point structure */
921 int needspace; /* file mode implies space allocated */
922 xfs_perag_t *pag; /* per allocation group data */
923 xfs_agnumber_t pagno; /* parent (starting) ag number */
924 int error;
925
926 /*
927 * Files of these types need at least one block if length > 0
928 * (and they won't fit in the inode, but that's hard to figure out).
929 */
930 needspace = S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode);
931 mp = tp->t_mountp;
932 agcount = mp->m_maxagi;
933 if (S_ISDIR(mode))
934 pagno = xfs_ialloc_next_ag(mp);
935 else {
936 pagno = XFS_INO_TO_AGNO(mp, parent);
937 if (pagno >= agcount)
938 pagno = 0;
939 }
940
941 ASSERT(pagno < agcount);
942
943 /*
944 * Loop through allocation groups, looking for one with a little
945 * free space in it. Note we don't look for free inodes, exactly.
946 * Instead, we include whether there is a need to allocate inodes
947 * to mean that blocks must be allocated for them,
948 * if none are currently free.
949 */
950 agno = pagno;
951 flags = XFS_ALLOC_FLAG_TRYLOCK;
952 for (;;) {
953 pag = xfs_perag_get(mp, agno);
954 if (!pag->pagi_inodeok) {
955 xfs_ialloc_next_ag(mp);
956 goto nextag;
957 }
958
959 if (!pag->pagi_init) {
960 error = xfs_ialloc_pagi_init(mp, tp, agno);
961 if (error)
962 goto nextag;
963 }
964
965 if (pag->pagi_freecount) {
966 xfs_perag_put(pag);
967 return agno;
968 }
969
970 if (!okalloc)
971 goto nextag;
972
973 if (!pag->pagf_init) {
974 error = xfs_alloc_pagf_init(mp, tp, agno, flags);
975 if (error)
976 goto nextag;
977 }
978
979 /*
980 * Check that there is enough free space for the file plus a
981 * chunk of inodes if we need to allocate some. If this is the
982 * first pass across the AGs, take into account the potential
983 * space needed for alignment of inode chunks when checking the
984 * longest contiguous free space in the AG - this prevents us
985 * from getting ENOSPC because we have free space larger than
986 * m_ialloc_blks but alignment constraints prevent us from using
987 * it.
988 *
989 * If we can't find an AG with space for full alignment slack to
990 * be taken into account, we must be near ENOSPC in all AGs.
991 * Hence we don't include alignment for the second pass and so
992 * if we fail allocation due to alignment issues then it is most
993 * likely a real ENOSPC condition.
994 */
995 ineed = mp->m_ialloc_min_blks;
996 if (flags && ineed > 1)
997 ineed += xfs_ialloc_cluster_alignment(mp);
998 longest = pag->pagf_longest;
999 if (!longest)
1000 longest = pag->pagf_flcount > 0;
1001
1002 if (pag->pagf_freeblks >= needspace + ineed &&
1003 longest >= ineed) {
1004 xfs_perag_put(pag);
1005 return agno;
1006 }
1007nextag:
1008 xfs_perag_put(pag);
1009 /*
1010 * No point in iterating over the rest, if we're shutting
1011 * down.
1012 */
1013 if (XFS_FORCED_SHUTDOWN(mp))
1014 return NULLAGNUMBER;
1015 agno++;
1016 if (agno >= agcount)
1017 agno = 0;
1018 if (agno == pagno) {
1019 if (flags == 0)
1020 return NULLAGNUMBER;
1021 flags = 0;
1022 }
1023 }
1024}
1025
1026/*
1027 * Try to retrieve the next record to the left/right from the current one.
1028 */
1029STATIC int
1030xfs_ialloc_next_rec(
1031 struct xfs_btree_cur *cur,
1032 xfs_inobt_rec_incore_t *rec,
1033 int *done,
1034 int left)
1035{
1036 int error;
1037 int i;
1038
1039 if (left)
1040 error = xfs_btree_decrement(cur, 0, &i);
1041 else
1042 error = xfs_btree_increment(cur, 0, &i);
1043
1044 if (error)
1045 return error;
1046 *done = !i;
1047 if (i) {
1048 error = xfs_inobt_get_rec(cur, rec, &i);
1049 if (error)
1050 return error;
1051 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, i == 1);
1052 }
1053
1054 return 0;
1055}
1056
1057STATIC int
1058xfs_ialloc_get_rec(
1059 struct xfs_btree_cur *cur,
1060 xfs_agino_t agino,
1061 xfs_inobt_rec_incore_t *rec,
1062 int *done)
1063{
1064 int error;
1065 int i;
1066
1067 error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_EQ, &i);
1068 if (error)
1069 return error;
1070 *done = !i;
1071 if (i) {
1072 error = xfs_inobt_get_rec(cur, rec, &i);
1073 if (error)
1074 return error;
1075 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, i == 1);
1076 }
1077
1078 return 0;
1079}
1080
1081/*
1082 * Return the offset of the first free inode in the record. If the inode chunk
1083 * is sparsely allocated, we convert the record holemask to inode granularity
1084 * and mask off the unallocated regions from the inode free mask.
1085 */
1086STATIC int
1087xfs_inobt_first_free_inode(
1088 struct xfs_inobt_rec_incore *rec)
1089{
1090 xfs_inofree_t realfree;
1091
1092 /* if there are no holes, return the first available offset */
1093 if (!xfs_inobt_issparse(rec->ir_holemask))
1094 return xfs_lowbit64(rec->ir_free);
1095
1096 realfree = xfs_inobt_irec_to_allocmask(rec);
1097 realfree &= rec->ir_free;
1098
1099 return xfs_lowbit64(realfree);
1100}
1101
1102/*
1103 * Allocate an inode using the inobt-only algorithm.
1104 */
1105STATIC int
1106xfs_dialloc_ag_inobt(
1107 struct xfs_trans *tp,
1108 struct xfs_buf *agbp,
1109 xfs_ino_t parent,
1110 xfs_ino_t *inop)
1111{
1112 struct xfs_mount *mp = tp->t_mountp;
1113 struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
1114 xfs_agnumber_t agno = be32_to_cpu(agi->agi_seqno);
1115 xfs_agnumber_t pagno = XFS_INO_TO_AGNO(mp, parent);
1116 xfs_agino_t pagino = XFS_INO_TO_AGINO(mp, parent);
1117 struct xfs_perag *pag;
1118 struct xfs_btree_cur *cur, *tcur;
1119 struct xfs_inobt_rec_incore rec, trec;
1120 xfs_ino_t ino;
1121 int error;
1122 int offset;
1123 int i, j;
1124
1125 pag = xfs_perag_get(mp, agno);
1126
1127 ASSERT(pag->pagi_init);
1128 ASSERT(pag->pagi_inodeok);
1129 ASSERT(pag->pagi_freecount > 0);
1130
1131 restart_pagno:
1132 cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_INO);
1133 /*
1134 * If pagino is 0 (this is the root inode allocation) use newino.
1135 * This must work because we've just allocated some.
1136 */
1137 if (!pagino)
1138 pagino = be32_to_cpu(agi->agi_newino);
1139
1140 error = xfs_check_agi_freecount(cur, agi);
1141 if (error)
1142 goto error0;
1143
1144 /*
1145 * If in the same AG as the parent, try to get near the parent.
1146 */
1147 if (pagno == agno) {
1148 int doneleft; /* done, to the left */
1149 int doneright; /* done, to the right */
1150 int searchdistance = 10;
1151
1152 error = xfs_inobt_lookup(cur, pagino, XFS_LOOKUP_LE, &i);
1153 if (error)
1154 goto error0;
1155 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1156
1157 error = xfs_inobt_get_rec(cur, &rec, &j);
1158 if (error)
1159 goto error0;
1160 XFS_WANT_CORRUPTED_GOTO(mp, j == 1, error0);
1161
1162 if (rec.ir_freecount > 0) {
1163 /*
1164 * Found a free inode in the same chunk
1165 * as the parent, done.
1166 */
1167 goto alloc_inode;
1168 }
1169
1170
1171 /*
1172 * In the same AG as parent, but parent's chunk is full.
1173 */
1174
1175 /* duplicate the cursor, search left & right simultaneously */
1176 error = xfs_btree_dup_cursor(cur, &tcur);
1177 if (error)
1178 goto error0;
1179
1180 /*
1181 * Skip to last blocks looked up if same parent inode.
1182 */
1183 if (pagino != NULLAGINO &&
1184 pag->pagl_pagino == pagino &&
1185 pag->pagl_leftrec != NULLAGINO &&
1186 pag->pagl_rightrec != NULLAGINO) {
1187 error = xfs_ialloc_get_rec(tcur, pag->pagl_leftrec,
1188 &trec, &doneleft);
1189 if (error)
1190 goto error1;
1191
1192 error = xfs_ialloc_get_rec(cur, pag->pagl_rightrec,
1193 &rec, &doneright);
1194 if (error)
1195 goto error1;
1196 } else {
1197 /* search left with tcur, back up 1 record */
1198 error = xfs_ialloc_next_rec(tcur, &trec, &doneleft, 1);
1199 if (error)
1200 goto error1;
1201
1202 /* search right with cur, go forward 1 record. */
1203 error = xfs_ialloc_next_rec(cur, &rec, &doneright, 0);
1204 if (error)
1205 goto error1;
1206 }
1207
1208 /*
1209 * Loop until we find an inode chunk with a free inode.
1210 */
1211 while (!doneleft || !doneright) {
1212 int useleft; /* using left inode chunk this time */
1213
1214 if (!--searchdistance) {
1215 /*
1216 * Not in range - save last search
1217 * location and allocate a new inode
1218 */
1219 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1220 pag->pagl_leftrec = trec.ir_startino;
1221 pag->pagl_rightrec = rec.ir_startino;
1222 pag->pagl_pagino = pagino;
1223 goto newino;
1224 }
1225
1226 /* figure out the closer block if both are valid. */
1227 if (!doneleft && !doneright) {
1228 useleft = pagino -
1229 (trec.ir_startino + XFS_INODES_PER_CHUNK - 1) <
1230 rec.ir_startino - pagino;
1231 } else {
1232 useleft = !doneleft;
1233 }
1234
1235 /* free inodes to the left? */
1236 if (useleft && trec.ir_freecount) {
1237 rec = trec;
1238 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1239 cur = tcur;
1240
1241 pag->pagl_leftrec = trec.ir_startino;
1242 pag->pagl_rightrec = rec.ir_startino;
1243 pag->pagl_pagino = pagino;
1244 goto alloc_inode;
1245 }
1246
1247 /* free inodes to the right? */
1248 if (!useleft && rec.ir_freecount) {
1249 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1250
1251 pag->pagl_leftrec = trec.ir_startino;
1252 pag->pagl_rightrec = rec.ir_startino;
1253 pag->pagl_pagino = pagino;
1254 goto alloc_inode;
1255 }
1256
1257 /* get next record to check */
1258 if (useleft) {
1259 error = xfs_ialloc_next_rec(tcur, &trec,
1260 &doneleft, 1);
1261 } else {
1262 error = xfs_ialloc_next_rec(cur, &rec,
1263 &doneright, 0);
1264 }
1265 if (error)
1266 goto error1;
1267 }
1268
1269 /*
1270 * We've reached the end of the btree. because
1271 * we are only searching a small chunk of the
1272 * btree each search, there is obviously free
1273 * inodes closer to the parent inode than we
1274 * are now. restart the search again.
1275 */
1276 pag->pagl_pagino = NULLAGINO;
1277 pag->pagl_leftrec = NULLAGINO;
1278 pag->pagl_rightrec = NULLAGINO;
1279 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
1280 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1281 goto restart_pagno;
1282 }
1283
1284 /*
1285 * In a different AG from the parent.
1286 * See if the most recently allocated block has any free.
1287 */
1288newino:
1289 if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
1290 error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
1291 XFS_LOOKUP_EQ, &i);
1292 if (error)
1293 goto error0;
1294
1295 if (i == 1) {
1296 error = xfs_inobt_get_rec(cur, &rec, &j);
1297 if (error)
1298 goto error0;
1299
1300 if (j == 1 && rec.ir_freecount > 0) {
1301 /*
1302 * The last chunk allocated in the group
1303 * still has a free inode.
1304 */
1305 goto alloc_inode;
1306 }
1307 }
1308 }
1309
1310 /*
1311 * None left in the last group, search the whole AG
1312 */
1313 error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
1314 if (error)
1315 goto error0;
1316 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1317
1318 for (;;) {
1319 error = xfs_inobt_get_rec(cur, &rec, &i);
1320 if (error)
1321 goto error0;
1322 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1323 if (rec.ir_freecount > 0)
1324 break;
1325 error = xfs_btree_increment(cur, 0, &i);
1326 if (error)
1327 goto error0;
1328 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1329 }
1330
1331alloc_inode:
1332 offset = xfs_inobt_first_free_inode(&rec);
1333 ASSERT(offset >= 0);
1334 ASSERT(offset < XFS_INODES_PER_CHUNK);
1335 ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
1336 XFS_INODES_PER_CHUNK) == 0);
1337 ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino + offset);
1338 rec.ir_free &= ~XFS_INOBT_MASK(offset);
1339 rec.ir_freecount--;
1340 error = xfs_inobt_update(cur, &rec);
1341 if (error)
1342 goto error0;
1343 be32_add_cpu(&agi->agi_freecount, -1);
1344 xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1345 pag->pagi_freecount--;
1346
1347 error = xfs_check_agi_freecount(cur, agi);
1348 if (error)
1349 goto error0;
1350
1351 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1352 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1353 xfs_perag_put(pag);
1354 *inop = ino;
1355 return 0;
1356error1:
1357 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
1358error0:
1359 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1360 xfs_perag_put(pag);
1361 return error;
1362}
1363
1364/*
1365 * Use the free inode btree to allocate an inode based on distance from the
1366 * parent. Note that the provided cursor may be deleted and replaced.
1367 */
1368STATIC int
1369xfs_dialloc_ag_finobt_near(
1370 xfs_agino_t pagino,
1371 struct xfs_btree_cur **ocur,
1372 struct xfs_inobt_rec_incore *rec)
1373{
1374 struct xfs_btree_cur *lcur = *ocur; /* left search cursor */
1375 struct xfs_btree_cur *rcur; /* right search cursor */
1376 struct xfs_inobt_rec_incore rrec;
1377 int error;
1378 int i, j;
1379
1380 error = xfs_inobt_lookup(lcur, pagino, XFS_LOOKUP_LE, &i);
1381 if (error)
1382 return error;
1383
1384 if (i == 1) {
1385 error = xfs_inobt_get_rec(lcur, rec, &i);
1386 if (error)
1387 return error;
1388 XFS_WANT_CORRUPTED_RETURN(lcur->bc_mp, i == 1);
1389
1390 /*
1391 * See if we've landed in the parent inode record. The finobt
1392 * only tracks chunks with at least one free inode, so record
1393 * existence is enough.
1394 */
1395 if (pagino >= rec->ir_startino &&
1396 pagino < (rec->ir_startino + XFS_INODES_PER_CHUNK))
1397 return 0;
1398 }
1399
1400 error = xfs_btree_dup_cursor(lcur, &rcur);
1401 if (error)
1402 return error;
1403
1404 error = xfs_inobt_lookup(rcur, pagino, XFS_LOOKUP_GE, &j);
1405 if (error)
1406 goto error_rcur;
1407 if (j == 1) {
1408 error = xfs_inobt_get_rec(rcur, &rrec, &j);
1409 if (error)
1410 goto error_rcur;
1411 XFS_WANT_CORRUPTED_GOTO(lcur->bc_mp, j == 1, error_rcur);
1412 }
1413
1414 XFS_WANT_CORRUPTED_GOTO(lcur->bc_mp, i == 1 || j == 1, error_rcur);
1415 if (i == 1 && j == 1) {
1416 /*
1417 * Both the left and right records are valid. Choose the closer
1418 * inode chunk to the target.
1419 */
1420 if ((pagino - rec->ir_startino + XFS_INODES_PER_CHUNK - 1) >
1421 (rrec.ir_startino - pagino)) {
1422 *rec = rrec;
1423 xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
1424 *ocur = rcur;
1425 } else {
1426 xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
1427 }
1428 } else if (j == 1) {
1429 /* only the right record is valid */
1430 *rec = rrec;
1431 xfs_btree_del_cursor(lcur, XFS_BTREE_NOERROR);
1432 *ocur = rcur;
1433 } else if (i == 1) {
1434 /* only the left record is valid */
1435 xfs_btree_del_cursor(rcur, XFS_BTREE_NOERROR);
1436 }
1437
1438 return 0;
1439
1440error_rcur:
1441 xfs_btree_del_cursor(rcur, XFS_BTREE_ERROR);
1442 return error;
1443}
1444
1445/*
1446 * Use the free inode btree to find a free inode based on a newino hint. If
1447 * the hint is NULL, find the first free inode in the AG.
1448 */
1449STATIC int
1450xfs_dialloc_ag_finobt_newino(
1451 struct xfs_agi *agi,
1452 struct xfs_btree_cur *cur,
1453 struct xfs_inobt_rec_incore *rec)
1454{
1455 int error;
1456 int i;
1457
1458 if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
1459 error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
1460 XFS_LOOKUP_EQ, &i);
1461 if (error)
1462 return error;
1463 if (i == 1) {
1464 error = xfs_inobt_get_rec(cur, rec, &i);
1465 if (error)
1466 return error;
1467 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, i == 1);
1468 return 0;
1469 }
1470 }
1471
1472 /*
1473 * Find the first inode available in the AG.
1474 */
1475 error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
1476 if (error)
1477 return error;
1478 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, i == 1);
1479
1480 error = xfs_inobt_get_rec(cur, rec, &i);
1481 if (error)
1482 return error;
1483 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, i == 1);
1484
1485 return 0;
1486}
1487
1488/*
1489 * Update the inobt based on a modification made to the finobt. Also ensure that
1490 * the records from both trees are equivalent post-modification.
1491 */
1492STATIC int
1493xfs_dialloc_ag_update_inobt(
1494 struct xfs_btree_cur *cur, /* inobt cursor */
1495 struct xfs_inobt_rec_incore *frec, /* finobt record */
1496 int offset) /* inode offset */
1497{
1498 struct xfs_inobt_rec_incore rec;
1499 int error;
1500 int i;
1501
1502 error = xfs_inobt_lookup(cur, frec->ir_startino, XFS_LOOKUP_EQ, &i);
1503 if (error)
1504 return error;
1505 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, i == 1);
1506
1507 error = xfs_inobt_get_rec(cur, &rec, &i);
1508 if (error)
1509 return error;
1510 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, i == 1);
1511 ASSERT((XFS_AGINO_TO_OFFSET(cur->bc_mp, rec.ir_startino) %
1512 XFS_INODES_PER_CHUNK) == 0);
1513
1514 rec.ir_free &= ~XFS_INOBT_MASK(offset);
1515 rec.ir_freecount--;
1516
1517 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, (rec.ir_free == frec->ir_free) &&
1518 (rec.ir_freecount == frec->ir_freecount));
1519
1520 return xfs_inobt_update(cur, &rec);
1521}
1522
1523/*
1524 * Allocate an inode using the free inode btree, if available. Otherwise, fall
1525 * back to the inobt search algorithm.
1526 *
1527 * The caller selected an AG for us, and made sure that free inodes are
1528 * available.
1529 */
1530STATIC int
1531xfs_dialloc_ag(
1532 struct xfs_trans *tp,
1533 struct xfs_buf *agbp,
1534 xfs_ino_t parent,
1535 xfs_ino_t *inop)
1536{
1537 struct xfs_mount *mp = tp->t_mountp;
1538 struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
1539 xfs_agnumber_t agno = be32_to_cpu(agi->agi_seqno);
1540 xfs_agnumber_t pagno = XFS_INO_TO_AGNO(mp, parent);
1541 xfs_agino_t pagino = XFS_INO_TO_AGINO(mp, parent);
1542 struct xfs_perag *pag;
1543 struct xfs_btree_cur *cur; /* finobt cursor */
1544 struct xfs_btree_cur *icur; /* inobt cursor */
1545 struct xfs_inobt_rec_incore rec;
1546 xfs_ino_t ino;
1547 int error;
1548 int offset;
1549 int i;
1550
1551 if (!xfs_sb_version_hasfinobt(&mp->m_sb))
1552 return xfs_dialloc_ag_inobt(tp, agbp, parent, inop);
1553
1554 pag = xfs_perag_get(mp, agno);
1555
1556 /*
1557 * If pagino is 0 (this is the root inode allocation) use newino.
1558 * This must work because we've just allocated some.
1559 */
1560 if (!pagino)
1561 pagino = be32_to_cpu(agi->agi_newino);
1562
1563 cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_FINO);
1564
1565 error = xfs_check_agi_freecount(cur, agi);
1566 if (error)
1567 goto error_cur;
1568
1569 /*
1570 * The search algorithm depends on whether we're in the same AG as the
1571 * parent. If so, find the closest available inode to the parent. If
1572 * not, consider the agi hint or find the first free inode in the AG.
1573 */
1574 if (agno == pagno)
1575 error = xfs_dialloc_ag_finobt_near(pagino, &cur, &rec);
1576 else
1577 error = xfs_dialloc_ag_finobt_newino(agi, cur, &rec);
1578 if (error)
1579 goto error_cur;
1580
1581 offset = xfs_inobt_first_free_inode(&rec);
1582 ASSERT(offset >= 0);
1583 ASSERT(offset < XFS_INODES_PER_CHUNK);
1584 ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
1585 XFS_INODES_PER_CHUNK) == 0);
1586 ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino + offset);
1587
1588 /*
1589 * Modify or remove the finobt record.
1590 */
1591 rec.ir_free &= ~XFS_INOBT_MASK(offset);
1592 rec.ir_freecount--;
1593 if (rec.ir_freecount)
1594 error = xfs_inobt_update(cur, &rec);
1595 else
1596 error = xfs_btree_delete(cur, &i);
1597 if (error)
1598 goto error_cur;
1599
1600 /*
1601 * The finobt has now been updated appropriately. We haven't updated the
1602 * agi and superblock yet, so we can create an inobt cursor and validate
1603 * the original freecount. If all is well, make the equivalent update to
1604 * the inobt using the finobt record and offset information.
1605 */
1606 icur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_INO);
1607
1608 error = xfs_check_agi_freecount(icur, agi);
1609 if (error)
1610 goto error_icur;
1611
1612 error = xfs_dialloc_ag_update_inobt(icur, &rec, offset);
1613 if (error)
1614 goto error_icur;
1615
1616 /*
1617 * Both trees have now been updated. We must update the perag and
1618 * superblock before we can check the freecount for each btree.
1619 */
1620 be32_add_cpu(&agi->agi_freecount, -1);
1621 xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1622 pag->pagi_freecount--;
1623
1624 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1625
1626 error = xfs_check_agi_freecount(icur, agi);
1627 if (error)
1628 goto error_icur;
1629 error = xfs_check_agi_freecount(cur, agi);
1630 if (error)
1631 goto error_icur;
1632
1633 xfs_btree_del_cursor(icur, XFS_BTREE_NOERROR);
1634 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1635 xfs_perag_put(pag);
1636 *inop = ino;
1637 return 0;
1638
1639error_icur:
1640 xfs_btree_del_cursor(icur, XFS_BTREE_ERROR);
1641error_cur:
1642 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1643 xfs_perag_put(pag);
1644 return error;
1645}
1646
1647/*
1648 * Allocate an inode on disk.
1649 *
1650 * Mode is used to tell whether the new inode will need space, and whether it
1651 * is a directory.
1652 *
1653 * This function is designed to be called twice if it has to do an allocation
1654 * to make more free inodes. On the first call, *IO_agbp should be set to NULL.
1655 * If an inode is available without having to performn an allocation, an inode
1656 * number is returned. In this case, *IO_agbp is set to NULL. If an allocation
1657 * needs to be done, xfs_dialloc returns the current AGI buffer in *IO_agbp.
1658 * The caller should then commit the current transaction, allocate a
1659 * new transaction, and call xfs_dialloc() again, passing in the previous value
1660 * of *IO_agbp. IO_agbp should be held across the transactions. Since the AGI
1661 * buffer is locked across the two calls, the second call is guaranteed to have
1662 * a free inode available.
1663 *
1664 * Once we successfully pick an inode its number is returned and the on-disk
1665 * data structures are updated. The inode itself is not read in, since doing so
1666 * would break ordering constraints with xfs_reclaim.
1667 */
1668int
1669xfs_dialloc(
1670 struct xfs_trans *tp,
1671 xfs_ino_t parent,
1672 umode_t mode,
1673 int okalloc,
1674 struct xfs_buf **IO_agbp,
1675 xfs_ino_t *inop)
1676{
1677 struct xfs_mount *mp = tp->t_mountp;
1678 struct xfs_buf *agbp;
1679 xfs_agnumber_t agno;
1680 int error;
1681 int ialloced;
1682 int noroom = 0;
1683 xfs_agnumber_t start_agno;
1684 struct xfs_perag *pag;
1685
1686 if (*IO_agbp) {
1687 /*
1688 * If the caller passes in a pointer to the AGI buffer,
1689 * continue where we left off before. In this case, we
1690 * know that the allocation group has free inodes.
1691 */
1692 agbp = *IO_agbp;
1693 goto out_alloc;
1694 }
1695
1696 /*
1697 * We do not have an agbp, so select an initial allocation
1698 * group for inode allocation.
1699 */
1700 start_agno = xfs_ialloc_ag_select(tp, parent, mode, okalloc);
1701 if (start_agno == NULLAGNUMBER) {
1702 *inop = NULLFSINO;
1703 return 0;
1704 }
1705
1706 /*
1707 * If we have already hit the ceiling of inode blocks then clear
1708 * okalloc so we scan all available agi structures for a free
1709 * inode.
1710 *
1711 * Read rough value of mp->m_icount by percpu_counter_read_positive,
1712 * which will sacrifice the preciseness but improve the performance.
1713 */
1714 if (mp->m_maxicount &&
1715 percpu_counter_read_positive(&mp->m_icount) + mp->m_ialloc_inos
1716 > mp->m_maxicount) {
1717 noroom = 1;
1718 okalloc = 0;
1719 }
1720
1721 /*
1722 * Loop until we find an allocation group that either has free inodes
1723 * or in which we can allocate some inodes. Iterate through the
1724 * allocation groups upward, wrapping at the end.
1725 */
1726 agno = start_agno;
1727 for (;;) {
1728 pag = xfs_perag_get(mp, agno);
1729 if (!pag->pagi_inodeok) {
1730 xfs_ialloc_next_ag(mp);
1731 goto nextag;
1732 }
1733
1734 if (!pag->pagi_init) {
1735 error = xfs_ialloc_pagi_init(mp, tp, agno);
1736 if (error)
1737 goto out_error;
1738 }
1739
1740 /*
1741 * Do a first racy fast path check if this AG is usable.
1742 */
1743 if (!pag->pagi_freecount && !okalloc)
1744 goto nextag;
1745
1746 /*
1747 * Then read in the AGI buffer and recheck with the AGI buffer
1748 * lock held.
1749 */
1750 error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
1751 if (error)
1752 goto out_error;
1753
1754 if (pag->pagi_freecount) {
1755 xfs_perag_put(pag);
1756 goto out_alloc;
1757 }
1758
1759 if (!okalloc)
1760 goto nextag_relse_buffer;
1761
1762
1763 error = xfs_ialloc_ag_alloc(tp, agbp, &ialloced);
1764 if (error) {
1765 xfs_trans_brelse(tp, agbp);
1766
1767 if (error != -ENOSPC)
1768 goto out_error;
1769
1770 xfs_perag_put(pag);
1771 *inop = NULLFSINO;
1772 return 0;
1773 }
1774
1775 if (ialloced) {
1776 /*
1777 * We successfully allocated some inodes, return
1778 * the current context to the caller so that it
1779 * can commit the current transaction and call
1780 * us again where we left off.
1781 */
1782 ASSERT(pag->pagi_freecount > 0);
1783 xfs_perag_put(pag);
1784
1785 *IO_agbp = agbp;
1786 *inop = NULLFSINO;
1787 return 0;
1788 }
1789
1790nextag_relse_buffer:
1791 xfs_trans_brelse(tp, agbp);
1792nextag:
1793 xfs_perag_put(pag);
1794 if (++agno == mp->m_sb.sb_agcount)
1795 agno = 0;
1796 if (agno == start_agno) {
1797 *inop = NULLFSINO;
1798 return noroom ? -ENOSPC : 0;
1799 }
1800 }
1801
1802out_alloc:
1803 *IO_agbp = NULL;
1804 return xfs_dialloc_ag(tp, agbp, parent, inop);
1805out_error:
1806 xfs_perag_put(pag);
1807 return error;
1808}
1809
1810/*
1811 * Free the blocks of an inode chunk. We must consider that the inode chunk
1812 * might be sparse and only free the regions that are allocated as part of the
1813 * chunk.
1814 */
1815STATIC void
1816xfs_difree_inode_chunk(
1817 struct xfs_mount *mp,
1818 xfs_agnumber_t agno,
1819 struct xfs_inobt_rec_incore *rec,
1820 struct xfs_bmap_free *flist)
1821{
1822 xfs_agblock_t sagbno = XFS_AGINO_TO_AGBNO(mp, rec->ir_startino);
1823 int startidx, endidx;
1824 int nextbit;
1825 xfs_agblock_t agbno;
1826 int contigblk;
1827 DECLARE_BITMAP(holemask, XFS_INOBT_HOLEMASK_BITS);
1828
1829 if (!xfs_inobt_issparse(rec->ir_holemask)) {
1830 /* not sparse, calculate extent info directly */
1831 xfs_bmap_add_free(XFS_AGB_TO_FSB(mp, agno,
1832 XFS_AGINO_TO_AGBNO(mp, rec->ir_startino)),
1833 mp->m_ialloc_blks, flist, mp);
1834 return;
1835 }
1836
1837 /* holemask is only 16-bits (fits in an unsigned long) */
1838 ASSERT(sizeof(rec->ir_holemask) <= sizeof(holemask[0]));
1839 holemask[0] = rec->ir_holemask;
1840
1841 /*
1842 * Find contiguous ranges of zeroes (i.e., allocated regions) in the
1843 * holemask and convert the start/end index of each range to an extent.
1844 * We start with the start and end index both pointing at the first 0 in
1845 * the mask.
1846 */
1847 startidx = endidx = find_first_zero_bit(holemask,
1848 XFS_INOBT_HOLEMASK_BITS);
1849 nextbit = startidx + 1;
1850 while (startidx < XFS_INOBT_HOLEMASK_BITS) {
1851 nextbit = find_next_zero_bit(holemask, XFS_INOBT_HOLEMASK_BITS,
1852 nextbit);
1853 /*
1854 * If the next zero bit is contiguous, update the end index of
1855 * the current range and continue.
1856 */
1857 if (nextbit != XFS_INOBT_HOLEMASK_BITS &&
1858 nextbit == endidx + 1) {
1859 endidx = nextbit;
1860 goto next;
1861 }
1862
1863 /*
1864 * nextbit is not contiguous with the current end index. Convert
1865 * the current start/end to an extent and add it to the free
1866 * list.
1867 */
1868 agbno = sagbno + (startidx * XFS_INODES_PER_HOLEMASK_BIT) /
1869 mp->m_sb.sb_inopblock;
1870 contigblk = ((endidx - startidx + 1) *
1871 XFS_INODES_PER_HOLEMASK_BIT) /
1872 mp->m_sb.sb_inopblock;
1873
1874 ASSERT(agbno % mp->m_sb.sb_spino_align == 0);
1875 ASSERT(contigblk % mp->m_sb.sb_spino_align == 0);
1876 xfs_bmap_add_free(XFS_AGB_TO_FSB(mp, agno, agbno), contigblk,
1877 flist, mp);
1878
1879 /* reset range to current bit and carry on... */
1880 startidx = endidx = nextbit;
1881
1882next:
1883 nextbit++;
1884 }
1885}
1886
1887STATIC int
1888xfs_difree_inobt(
1889 struct xfs_mount *mp,
1890 struct xfs_trans *tp,
1891 struct xfs_buf *agbp,
1892 xfs_agino_t agino,
1893 struct xfs_bmap_free *flist,
1894 struct xfs_icluster *xic,
1895 struct xfs_inobt_rec_incore *orec)
1896{
1897 struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
1898 xfs_agnumber_t agno = be32_to_cpu(agi->agi_seqno);
1899 struct xfs_perag *pag;
1900 struct xfs_btree_cur *cur;
1901 struct xfs_inobt_rec_incore rec;
1902 int ilen;
1903 int error;
1904 int i;
1905 int off;
1906
1907 ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
1908 ASSERT(XFS_AGINO_TO_AGBNO(mp, agino) < be32_to_cpu(agi->agi_length));
1909
1910 /*
1911 * Initialize the cursor.
1912 */
1913 cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_INO);
1914
1915 error = xfs_check_agi_freecount(cur, agi);
1916 if (error)
1917 goto error0;
1918
1919 /*
1920 * Look for the entry describing this inode.
1921 */
1922 if ((error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i))) {
1923 xfs_warn(mp, "%s: xfs_inobt_lookup() returned error %d.",
1924 __func__, error);
1925 goto error0;
1926 }
1927 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1928 error = xfs_inobt_get_rec(cur, &rec, &i);
1929 if (error) {
1930 xfs_warn(mp, "%s: xfs_inobt_get_rec() returned error %d.",
1931 __func__, error);
1932 goto error0;
1933 }
1934 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1935 /*
1936 * Get the offset in the inode chunk.
1937 */
1938 off = agino - rec.ir_startino;
1939 ASSERT(off >= 0 && off < XFS_INODES_PER_CHUNK);
1940 ASSERT(!(rec.ir_free & XFS_INOBT_MASK(off)));
1941 /*
1942 * Mark the inode free & increment the count.
1943 */
1944 rec.ir_free |= XFS_INOBT_MASK(off);
1945 rec.ir_freecount++;
1946
1947 /*
1948 * When an inode chunk is free, it becomes eligible for removal. Don't
1949 * remove the chunk if the block size is large enough for multiple inode
1950 * chunks (that might not be free).
1951 */
1952 if (!(mp->m_flags & XFS_MOUNT_IKEEP) &&
1953 rec.ir_free == XFS_INOBT_ALL_FREE &&
1954 mp->m_sb.sb_inopblock <= XFS_INODES_PER_CHUNK) {
1955 xic->deleted = 1;
1956 xic->first_ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino);
1957 xic->alloc = xfs_inobt_irec_to_allocmask(&rec);
1958
1959 /*
1960 * Remove the inode cluster from the AGI B+Tree, adjust the
1961 * AGI and Superblock inode counts, and mark the disk space
1962 * to be freed when the transaction is committed.
1963 */
1964 ilen = rec.ir_freecount;
1965 be32_add_cpu(&agi->agi_count, -ilen);
1966 be32_add_cpu(&agi->agi_freecount, -(ilen - 1));
1967 xfs_ialloc_log_agi(tp, agbp, XFS_AGI_COUNT | XFS_AGI_FREECOUNT);
1968 pag = xfs_perag_get(mp, agno);
1969 pag->pagi_freecount -= ilen - 1;
1970 xfs_perag_put(pag);
1971 xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, -ilen);
1972 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -(ilen - 1));
1973
1974 if ((error = xfs_btree_delete(cur, &i))) {
1975 xfs_warn(mp, "%s: xfs_btree_delete returned error %d.",
1976 __func__, error);
1977 goto error0;
1978 }
1979
1980 xfs_difree_inode_chunk(mp, agno, &rec, flist);
1981 } else {
1982 xic->deleted = 0;
1983
1984 error = xfs_inobt_update(cur, &rec);
1985 if (error) {
1986 xfs_warn(mp, "%s: xfs_inobt_update returned error %d.",
1987 __func__, error);
1988 goto error0;
1989 }
1990
1991 /*
1992 * Change the inode free counts and log the ag/sb changes.
1993 */
1994 be32_add_cpu(&agi->agi_freecount, 1);
1995 xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1996 pag = xfs_perag_get(mp, agno);
1997 pag->pagi_freecount++;
1998 xfs_perag_put(pag);
1999 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, 1);
2000 }
2001
2002 error = xfs_check_agi_freecount(cur, agi);
2003 if (error)
2004 goto error0;
2005
2006 *orec = rec;
2007 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
2008 return 0;
2009
2010error0:
2011 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
2012 return error;
2013}
2014
2015/*
2016 * Free an inode in the free inode btree.
2017 */
2018STATIC int
2019xfs_difree_finobt(
2020 struct xfs_mount *mp,
2021 struct xfs_trans *tp,
2022 struct xfs_buf *agbp,
2023 xfs_agino_t agino,
2024 struct xfs_inobt_rec_incore *ibtrec) /* inobt record */
2025{
2026 struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
2027 xfs_agnumber_t agno = be32_to_cpu(agi->agi_seqno);
2028 struct xfs_btree_cur *cur;
2029 struct xfs_inobt_rec_incore rec;
2030 int offset = agino - ibtrec->ir_startino;
2031 int error;
2032 int i;
2033
2034 cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_FINO);
2035
2036 error = xfs_inobt_lookup(cur, ibtrec->ir_startino, XFS_LOOKUP_EQ, &i);
2037 if (error)
2038 goto error;
2039 if (i == 0) {
2040 /*
2041 * If the record does not exist in the finobt, we must have just
2042 * freed an inode in a previously fully allocated chunk. If not,
2043 * something is out of sync.
2044 */
2045 XFS_WANT_CORRUPTED_GOTO(mp, ibtrec->ir_freecount == 1, error);
2046
2047 error = xfs_inobt_insert_rec(cur, ibtrec->ir_holemask,
2048 ibtrec->ir_count,
2049 ibtrec->ir_freecount,
2050 ibtrec->ir_free, &i);
2051 if (error)
2052 goto error;
2053 ASSERT(i == 1);
2054
2055 goto out;
2056 }
2057
2058 /*
2059 * Read and update the existing record. We could just copy the ibtrec
2060 * across here, but that would defeat the purpose of having redundant
2061 * metadata. By making the modifications independently, we can catch
2062 * corruptions that we wouldn't see if we just copied from one record
2063 * to another.
2064 */
2065 error = xfs_inobt_get_rec(cur, &rec, &i);
2066 if (error)
2067 goto error;
2068 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error);
2069
2070 rec.ir_free |= XFS_INOBT_MASK(offset);
2071 rec.ir_freecount++;
2072
2073 XFS_WANT_CORRUPTED_GOTO(mp, (rec.ir_free == ibtrec->ir_free) &&
2074 (rec.ir_freecount == ibtrec->ir_freecount),
2075 error);
2076
2077 /*
2078 * The content of inobt records should always match between the inobt
2079 * and finobt. The lifecycle of records in the finobt is different from
2080 * the inobt in that the finobt only tracks records with at least one
2081 * free inode. Hence, if all of the inodes are free and we aren't
2082 * keeping inode chunks permanently on disk, remove the record.
2083 * Otherwise, update the record with the new information.
2084 *
2085 * Note that we currently can't free chunks when the block size is large
2086 * enough for multiple chunks. Leave the finobt record to remain in sync
2087 * with the inobt.
2088 */
2089 if (rec.ir_free == XFS_INOBT_ALL_FREE &&
2090 mp->m_sb.sb_inopblock <= XFS_INODES_PER_CHUNK &&
2091 !(mp->m_flags & XFS_MOUNT_IKEEP)) {
2092 error = xfs_btree_delete(cur, &i);
2093 if (error)
2094 goto error;
2095 ASSERT(i == 1);
2096 } else {
2097 error = xfs_inobt_update(cur, &rec);
2098 if (error)
2099 goto error;
2100 }
2101
2102out:
2103 error = xfs_check_agi_freecount(cur, agi);
2104 if (error)
2105 goto error;
2106
2107 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
2108 return 0;
2109
2110error:
2111 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
2112 return error;
2113}
2114
2115/*
2116 * Free disk inode. Carefully avoids touching the incore inode, all
2117 * manipulations incore are the caller's responsibility.
2118 * The on-disk inode is not changed by this operation, only the
2119 * btree (free inode mask) is changed.
2120 */
2121int
2122xfs_difree(
2123 struct xfs_trans *tp, /* transaction pointer */
2124 xfs_ino_t inode, /* inode to be freed */
2125 struct xfs_bmap_free *flist, /* extents to free */
2126 struct xfs_icluster *xic) /* cluster info if deleted */
2127{
2128 /* REFERENCED */
2129 xfs_agblock_t agbno; /* block number containing inode */
2130 struct xfs_buf *agbp; /* buffer for allocation group header */
2131 xfs_agino_t agino; /* allocation group inode number */
2132 xfs_agnumber_t agno; /* allocation group number */
2133 int error; /* error return value */
2134 struct xfs_mount *mp; /* mount structure for filesystem */
2135 struct xfs_inobt_rec_incore rec;/* btree record */
2136
2137 mp = tp->t_mountp;
2138
2139 /*
2140 * Break up inode number into its components.
2141 */
2142 agno = XFS_INO_TO_AGNO(mp, inode);
2143 if (agno >= mp->m_sb.sb_agcount) {
2144 xfs_warn(mp, "%s: agno >= mp->m_sb.sb_agcount (%d >= %d).",
2145 __func__, agno, mp->m_sb.sb_agcount);
2146 ASSERT(0);
2147 return -EINVAL;
2148 }
2149 agino = XFS_INO_TO_AGINO(mp, inode);
2150 if (inode != XFS_AGINO_TO_INO(mp, agno, agino)) {
2151 xfs_warn(mp, "%s: inode != XFS_AGINO_TO_INO() (%llu != %llu).",
2152 __func__, (unsigned long long)inode,
2153 (unsigned long long)XFS_AGINO_TO_INO(mp, agno, agino));
2154 ASSERT(0);
2155 return -EINVAL;
2156 }
2157 agbno = XFS_AGINO_TO_AGBNO(mp, agino);
2158 if (agbno >= mp->m_sb.sb_agblocks) {
2159 xfs_warn(mp, "%s: agbno >= mp->m_sb.sb_agblocks (%d >= %d).",
2160 __func__, agbno, mp->m_sb.sb_agblocks);
2161 ASSERT(0);
2162 return -EINVAL;
2163 }
2164 /*
2165 * Get the allocation group header.
2166 */
2167 error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
2168 if (error) {
2169 xfs_warn(mp, "%s: xfs_ialloc_read_agi() returned error %d.",
2170 __func__, error);
2171 return error;
2172 }
2173
2174 /*
2175 * Fix up the inode allocation btree.
2176 */
2177 error = xfs_difree_inobt(mp, tp, agbp, agino, flist, xic, &rec);
2178 if (error)
2179 goto error0;
2180
2181 /*
2182 * Fix up the free inode btree.
2183 */
2184 if (xfs_sb_version_hasfinobt(&mp->m_sb)) {
2185 error = xfs_difree_finobt(mp, tp, agbp, agino, &rec);
2186 if (error)
2187 goto error0;
2188 }
2189
2190 return 0;
2191
2192error0:
2193 return error;
2194}
2195
2196STATIC int
2197xfs_imap_lookup(
2198 struct xfs_mount *mp,
2199 struct xfs_trans *tp,
2200 xfs_agnumber_t agno,
2201 xfs_agino_t agino,
2202 xfs_agblock_t agbno,
2203 xfs_agblock_t *chunk_agbno,
2204 xfs_agblock_t *offset_agbno,
2205 int flags)
2206{
2207 struct xfs_inobt_rec_incore rec;
2208 struct xfs_btree_cur *cur;
2209 struct xfs_buf *agbp;
2210 int error;
2211 int i;
2212
2213 error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
2214 if (error) {
2215 xfs_alert(mp,
2216 "%s: xfs_ialloc_read_agi() returned error %d, agno %d",
2217 __func__, error, agno);
2218 return error;
2219 }
2220
2221 /*
2222 * Lookup the inode record for the given agino. If the record cannot be
2223 * found, then it's an invalid inode number and we should abort. Once
2224 * we have a record, we need to ensure it contains the inode number
2225 * we are looking up.
2226 */
2227 cur = xfs_inobt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_INO);
2228 error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i);
2229 if (!error) {
2230 if (i)
2231 error = xfs_inobt_get_rec(cur, &rec, &i);
2232 if (!error && i == 0)
2233 error = -EINVAL;
2234 }
2235
2236 xfs_trans_brelse(tp, agbp);
2237 xfs_btree_del_cursor(cur, error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
2238 if (error)
2239 return error;
2240
2241 /* check that the returned record contains the required inode */
2242 if (rec.ir_startino > agino ||
2243 rec.ir_startino + mp->m_ialloc_inos <= agino)
2244 return -EINVAL;
2245
2246 /* for untrusted inodes check it is allocated first */
2247 if ((flags & XFS_IGET_UNTRUSTED) &&
2248 (rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino)))
2249 return -EINVAL;
2250
2251 *chunk_agbno = XFS_AGINO_TO_AGBNO(mp, rec.ir_startino);
2252 *offset_agbno = agbno - *chunk_agbno;
2253 return 0;
2254}
2255
2256/*
2257 * Return the location of the inode in imap, for mapping it into a buffer.
2258 */
2259int
2260xfs_imap(
2261 xfs_mount_t *mp, /* file system mount structure */
2262 xfs_trans_t *tp, /* transaction pointer */
2263 xfs_ino_t ino, /* inode to locate */
2264 struct xfs_imap *imap, /* location map structure */
2265 uint flags) /* flags for inode btree lookup */
2266{
2267 xfs_agblock_t agbno; /* block number of inode in the alloc group */
2268 xfs_agino_t agino; /* inode number within alloc group */
2269 xfs_agnumber_t agno; /* allocation group number */
2270 int blks_per_cluster; /* num blocks per inode cluster */
2271 xfs_agblock_t chunk_agbno; /* first block in inode chunk */
2272 xfs_agblock_t cluster_agbno; /* first block in inode cluster */
2273 int error; /* error code */
2274 int offset; /* index of inode in its buffer */
2275 xfs_agblock_t offset_agbno; /* blks from chunk start to inode */
2276
2277 ASSERT(ino != NULLFSINO);
2278
2279 /*
2280 * Split up the inode number into its parts.
2281 */
2282 agno = XFS_INO_TO_AGNO(mp, ino);
2283 agino = XFS_INO_TO_AGINO(mp, ino);
2284 agbno = XFS_AGINO_TO_AGBNO(mp, agino);
2285 if (agno >= mp->m_sb.sb_agcount || agbno >= mp->m_sb.sb_agblocks ||
2286 ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
2287#ifdef DEBUG
2288 /*
2289 * Don't output diagnostic information for untrusted inodes
2290 * as they can be invalid without implying corruption.
2291 */
2292 if (flags & XFS_IGET_UNTRUSTED)
2293 return -EINVAL;
2294 if (agno >= mp->m_sb.sb_agcount) {
2295 xfs_alert(mp,
2296 "%s: agno (%d) >= mp->m_sb.sb_agcount (%d)",
2297 __func__, agno, mp->m_sb.sb_agcount);
2298 }
2299 if (agbno >= mp->m_sb.sb_agblocks) {
2300 xfs_alert(mp,
2301 "%s: agbno (0x%llx) >= mp->m_sb.sb_agblocks (0x%lx)",
2302 __func__, (unsigned long long)agbno,
2303 (unsigned long)mp->m_sb.sb_agblocks);
2304 }
2305 if (ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
2306 xfs_alert(mp,
2307 "%s: ino (0x%llx) != XFS_AGINO_TO_INO() (0x%llx)",
2308 __func__, ino,
2309 XFS_AGINO_TO_INO(mp, agno, agino));
2310 }
2311 xfs_stack_trace();
2312#endif /* DEBUG */
2313 return -EINVAL;
2314 }
2315
2316 blks_per_cluster = xfs_icluster_size_fsb(mp);
2317
2318 /*
2319 * For bulkstat and handle lookups, we have an untrusted inode number
2320 * that we have to verify is valid. We cannot do this just by reading
2321 * the inode buffer as it may have been unlinked and removed leaving
2322 * inodes in stale state on disk. Hence we have to do a btree lookup
2323 * in all cases where an untrusted inode number is passed.
2324 */
2325 if (flags & XFS_IGET_UNTRUSTED) {
2326 error = xfs_imap_lookup(mp, tp, agno, agino, agbno,
2327 &chunk_agbno, &offset_agbno, flags);
2328 if (error)
2329 return error;
2330 goto out_map;
2331 }
2332
2333 /*
2334 * If the inode cluster size is the same as the blocksize or
2335 * smaller we get to the buffer by simple arithmetics.
2336 */
2337 if (blks_per_cluster == 1) {
2338 offset = XFS_INO_TO_OFFSET(mp, ino);
2339 ASSERT(offset < mp->m_sb.sb_inopblock);
2340
2341 imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, agbno);
2342 imap->im_len = XFS_FSB_TO_BB(mp, 1);
2343 imap->im_boffset = (ushort)(offset << mp->m_sb.sb_inodelog);
2344 return 0;
2345 }
2346
2347 /*
2348 * If the inode chunks are aligned then use simple maths to
2349 * find the location. Otherwise we have to do a btree
2350 * lookup to find the location.
2351 */
2352 if (mp->m_inoalign_mask) {
2353 offset_agbno = agbno & mp->m_inoalign_mask;
2354 chunk_agbno = agbno - offset_agbno;
2355 } else {
2356 error = xfs_imap_lookup(mp, tp, agno, agino, agbno,
2357 &chunk_agbno, &offset_agbno, flags);
2358 if (error)
2359 return error;
2360 }
2361
2362out_map:
2363 ASSERT(agbno >= chunk_agbno);
2364 cluster_agbno = chunk_agbno +
2365 ((offset_agbno / blks_per_cluster) * blks_per_cluster);
2366 offset = ((agbno - cluster_agbno) * mp->m_sb.sb_inopblock) +
2367 XFS_INO_TO_OFFSET(mp, ino);
2368
2369 imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, cluster_agbno);
2370 imap->im_len = XFS_FSB_TO_BB(mp, blks_per_cluster);
2371 imap->im_boffset = (ushort)(offset << mp->m_sb.sb_inodelog);
2372
2373 /*
2374 * If the inode number maps to a block outside the bounds
2375 * of the file system then return NULL rather than calling
2376 * read_buf and panicing when we get an error from the
2377 * driver.
2378 */
2379 if ((imap->im_blkno + imap->im_len) >
2380 XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
2381 xfs_alert(mp,
2382 "%s: (im_blkno (0x%llx) + im_len (0x%llx)) > sb_dblocks (0x%llx)",
2383 __func__, (unsigned long long) imap->im_blkno,
2384 (unsigned long long) imap->im_len,
2385 XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks));
2386 return -EINVAL;
2387 }
2388 return 0;
2389}
2390
2391/*
2392 * Compute and fill in value of m_in_maxlevels.
2393 */
2394void
2395xfs_ialloc_compute_maxlevels(
2396 xfs_mount_t *mp) /* file system mount structure */
2397{
2398 int level;
2399 uint maxblocks;
2400 uint maxleafents;
2401 int minleafrecs;
2402 int minnoderecs;
2403
2404 maxleafents = (1LL << XFS_INO_AGINO_BITS(mp)) >>
2405 XFS_INODES_PER_CHUNK_LOG;
2406 minleafrecs = mp->m_inobt_mnr[0];
2407 minnoderecs = mp->m_inobt_mnr[1];
2408 maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs;
2409 for (level = 1; maxblocks > 1; level++)
2410 maxblocks = (maxblocks + minnoderecs - 1) / minnoderecs;
2411 mp->m_in_maxlevels = level;
2412}
2413
2414/*
2415 * Log specified fields for the ag hdr (inode section). The growth of the agi
2416 * structure over time requires that we interpret the buffer as two logical
2417 * regions delineated by the end of the unlinked list. This is due to the size
2418 * of the hash table and its location in the middle of the agi.
2419 *
2420 * For example, a request to log a field before agi_unlinked and a field after
2421 * agi_unlinked could cause us to log the entire hash table and use an excessive
2422 * amount of log space. To avoid this behavior, log the region up through
2423 * agi_unlinked in one call and the region after agi_unlinked through the end of
2424 * the structure in another.
2425 */
2426void
2427xfs_ialloc_log_agi(
2428 xfs_trans_t *tp, /* transaction pointer */
2429 xfs_buf_t *bp, /* allocation group header buffer */
2430 int fields) /* bitmask of fields to log */
2431{
2432 int first; /* first byte number */
2433 int last; /* last byte number */
2434 static const short offsets[] = { /* field starting offsets */
2435 /* keep in sync with bit definitions */
2436 offsetof(xfs_agi_t, agi_magicnum),
2437 offsetof(xfs_agi_t, agi_versionnum),
2438 offsetof(xfs_agi_t, agi_seqno),
2439 offsetof(xfs_agi_t, agi_length),
2440 offsetof(xfs_agi_t, agi_count),
2441 offsetof(xfs_agi_t, agi_root),
2442 offsetof(xfs_agi_t, agi_level),
2443 offsetof(xfs_agi_t, agi_freecount),
2444 offsetof(xfs_agi_t, agi_newino),
2445 offsetof(xfs_agi_t, agi_dirino),
2446 offsetof(xfs_agi_t, agi_unlinked),
2447 offsetof(xfs_agi_t, agi_free_root),
2448 offsetof(xfs_agi_t, agi_free_level),
2449 sizeof(xfs_agi_t)
2450 };
2451#ifdef DEBUG
2452 xfs_agi_t *agi; /* allocation group header */
2453
2454 agi = XFS_BUF_TO_AGI(bp);
2455 ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
2456#endif
2457
2458 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_AGI_BUF);
2459
2460 /*
2461 * Compute byte offsets for the first and last fields in the first
2462 * region and log the agi buffer. This only logs up through
2463 * agi_unlinked.
2464 */
2465 if (fields & XFS_AGI_ALL_BITS_R1) {
2466 xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R1,
2467 &first, &last);
2468 xfs_trans_log_buf(tp, bp, first, last);
2469 }
2470
2471 /*
2472 * Mask off the bits in the first region and calculate the first and
2473 * last field offsets for any bits in the second region.
2474 */
2475 fields &= ~XFS_AGI_ALL_BITS_R1;
2476 if (fields) {
2477 xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS_R2,
2478 &first, &last);
2479 xfs_trans_log_buf(tp, bp, first, last);
2480 }
2481}
2482
2483#ifdef DEBUG
2484STATIC void
2485xfs_check_agi_unlinked(
2486 struct xfs_agi *agi)
2487{
2488 int i;
2489
2490 for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++)
2491 ASSERT(agi->agi_unlinked[i]);
2492}
2493#else
2494#define xfs_check_agi_unlinked(agi)
2495#endif
2496
2497static bool
2498xfs_agi_verify(
2499 struct xfs_buf *bp)
2500{
2501 struct xfs_mount *mp = bp->b_target->bt_mount;
2502 struct xfs_agi *agi = XFS_BUF_TO_AGI(bp);
2503
2504 if (xfs_sb_version_hascrc(&mp->m_sb)) {
2505 if (!uuid_equal(&agi->agi_uuid, &mp->m_sb.sb_meta_uuid))
2506 return false;
2507 if (!xfs_log_check_lsn(mp,
2508 be64_to_cpu(XFS_BUF_TO_AGI(bp)->agi_lsn)))
2509 return false;
2510 }
2511
2512 /*
2513 * Validate the magic number of the agi block.
2514 */
2515 if (agi->agi_magicnum != cpu_to_be32(XFS_AGI_MAGIC))
2516 return false;
2517 if (!XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)))
2518 return false;
2519
2520 if (be32_to_cpu(agi->agi_level) > XFS_BTREE_MAXLEVELS)
2521 return false;
2522 /*
2523 * during growfs operations, the perag is not fully initialised,
2524 * so we can't use it for any useful checking. growfs ensures we can't
2525 * use it by using uncached buffers that don't have the perag attached
2526 * so we can detect and avoid this problem.
2527 */
2528 if (bp->b_pag && be32_to_cpu(agi->agi_seqno) != bp->b_pag->pag_agno)
2529 return false;
2530
2531 xfs_check_agi_unlinked(agi);
2532 return true;
2533}
2534
2535static void
2536xfs_agi_read_verify(
2537 struct xfs_buf *bp)
2538{
2539 struct xfs_mount *mp = bp->b_target->bt_mount;
2540
2541 if (xfs_sb_version_hascrc(&mp->m_sb) &&
2542 !xfs_buf_verify_cksum(bp, XFS_AGI_CRC_OFF))
2543 xfs_buf_ioerror(bp, -EFSBADCRC);
2544 else if (XFS_TEST_ERROR(!xfs_agi_verify(bp), mp,
2545 XFS_ERRTAG_IALLOC_READ_AGI,
2546 XFS_RANDOM_IALLOC_READ_AGI))
2547 xfs_buf_ioerror(bp, -EFSCORRUPTED);
2548
2549 if (bp->b_error)
2550 xfs_verifier_error(bp);
2551}
2552
2553static void
2554xfs_agi_write_verify(
2555 struct xfs_buf *bp)
2556{
2557 struct xfs_mount *mp = bp->b_target->bt_mount;
2558 struct xfs_buf_log_item *bip = bp->b_fspriv;
2559
2560 if (!xfs_agi_verify(bp)) {
2561 xfs_buf_ioerror(bp, -EFSCORRUPTED);
2562 xfs_verifier_error(bp);
2563 return;
2564 }
2565
2566 if (!xfs_sb_version_hascrc(&mp->m_sb))
2567 return;
2568
2569 if (bip)
2570 XFS_BUF_TO_AGI(bp)->agi_lsn = cpu_to_be64(bip->bli_item.li_lsn);
2571 xfs_buf_update_cksum(bp, XFS_AGI_CRC_OFF);
2572}
2573
2574const struct xfs_buf_ops xfs_agi_buf_ops = {
2575 .name = "xfs_agi",
2576 .verify_read = xfs_agi_read_verify,
2577 .verify_write = xfs_agi_write_verify,
2578};
2579
2580/*
2581 * Read in the allocation group header (inode allocation section)
2582 */
2583int
2584xfs_read_agi(
2585 struct xfs_mount *mp, /* file system mount structure */
2586 struct xfs_trans *tp, /* transaction pointer */
2587 xfs_agnumber_t agno, /* allocation group number */
2588 struct xfs_buf **bpp) /* allocation group hdr buf */
2589{
2590 int error;
2591
2592 trace_xfs_read_agi(mp, agno);
2593
2594 ASSERT(agno != NULLAGNUMBER);
2595 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
2596 XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
2597 XFS_FSS_TO_BB(mp, 1), 0, bpp, &xfs_agi_buf_ops);
2598 if (error)
2599 return error;
2600
2601 xfs_buf_set_ref(*bpp, XFS_AGI_REF);
2602 return 0;
2603}
2604
2605int
2606xfs_ialloc_read_agi(
2607 struct xfs_mount *mp, /* file system mount structure */
2608 struct xfs_trans *tp, /* transaction pointer */
2609 xfs_agnumber_t agno, /* allocation group number */
2610 struct xfs_buf **bpp) /* allocation group hdr buf */
2611{
2612 struct xfs_agi *agi; /* allocation group header */
2613 struct xfs_perag *pag; /* per allocation group data */
2614 int error;
2615
2616 trace_xfs_ialloc_read_agi(mp, agno);
2617
2618 error = xfs_read_agi(mp, tp, agno, bpp);
2619 if (error)
2620 return error;
2621
2622 agi = XFS_BUF_TO_AGI(*bpp);
2623 pag = xfs_perag_get(mp, agno);
2624 if (!pag->pagi_init) {
2625 pag->pagi_freecount = be32_to_cpu(agi->agi_freecount);
2626 pag->pagi_count = be32_to_cpu(agi->agi_count);
2627 pag->pagi_init = 1;
2628 }
2629
2630 /*
2631 * It's possible for these to be out of sync if
2632 * we are in the middle of a forced shutdown.
2633 */
2634 ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) ||
2635 XFS_FORCED_SHUTDOWN(mp));
2636 xfs_perag_put(pag);
2637 return 0;
2638}
2639
2640/*
2641 * Read in the agi to initialise the per-ag data in the mount structure
2642 */
2643int
2644xfs_ialloc_pagi_init(
2645 xfs_mount_t *mp, /* file system mount structure */
2646 xfs_trans_t *tp, /* transaction pointer */
2647 xfs_agnumber_t agno) /* allocation group number */
2648{
2649 xfs_buf_t *bp = NULL;
2650 int error;
2651
2652 error = xfs_ialloc_read_agi(mp, tp, agno, &bp);
2653 if (error)
2654 return error;
2655 if (bp)
2656 xfs_trans_brelse(tp, bp);
2657 return 0;
2658}