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dm mpath: check if scsi_dh module already loaded before trying to load
[zen-stable.git] / fs / xfs / xfs_ialloc.c
blobdad1a31aa4fca504c8f4103e85e4b027793d791a
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_types.h"
21 #include "xfs_bit.h"
22 #include "xfs_log.h"
23 #include "xfs_inum.h"
24 #include "xfs_trans.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_mount.h"
28 #include "xfs_bmap_btree.h"
29 #include "xfs_alloc_btree.h"
30 #include "xfs_ialloc_btree.h"
31 #include "xfs_dinode.h"
32 #include "xfs_inode.h"
33 #include "xfs_btree.h"
34 #include "xfs_ialloc.h"
35 #include "xfs_alloc.h"
36 #include "xfs_rtalloc.h"
37 #include "xfs_error.h"
38 #include "xfs_bmap.h"
39
40
41 /*
42 * Allocation group level functions.
43 */
44 static inline int
45 xfs_ialloc_cluster_alignment(
46 xfs_alloc_arg_t *args)
47 {
48 if (xfs_sb_version_hasalign(&args->mp->m_sb) &&
49 args->mp->m_sb.sb_inoalignmt >=
50 XFS_B_TO_FSBT(args->mp, XFS_INODE_CLUSTER_SIZE(args->mp)))
51 return args->mp->m_sb.sb_inoalignmt;
52 return 1;
53 }
54
55 /*
56 * Lookup a record by ino in the btree given by cur.
57 */
58 int /* error */
59 xfs_inobt_lookup(
60 struct xfs_btree_cur *cur, /* btree cursor */
61 xfs_agino_t ino, /* starting inode of chunk */
62 xfs_lookup_t dir, /* <=, >=, == */
63 int *stat) /* success/failure */
64 {
65 cur->bc_rec.i.ir_startino = ino;
66 cur->bc_rec.i.ir_freecount = 0;
67 cur->bc_rec.i.ir_free = 0;
68 return xfs_btree_lookup(cur, dir, stat);
69 }
70
71 /*
72 * Update the record referred to by cur to the value given.
73 * This either works (return 0) or gets an EFSCORRUPTED error.
74 */
75 STATIC int /* error */
76 xfs_inobt_update(
77 struct xfs_btree_cur *cur, /* btree cursor */
78 xfs_inobt_rec_incore_t *irec) /* btree record */
79 {
80 union xfs_btree_rec rec;
81
82 rec.inobt.ir_startino = cpu_to_be32(irec->ir_startino);
83 rec.inobt.ir_freecount = cpu_to_be32(irec->ir_freecount);
84 rec.inobt.ir_free = cpu_to_be64(irec->ir_free);
85 return xfs_btree_update(cur, &rec);
86 }
87
88 /*
89 * Get the data from the pointed-to record.
90 */
91 int /* error */
92 xfs_inobt_get_rec(
93 struct xfs_btree_cur *cur, /* btree cursor */
94 xfs_inobt_rec_incore_t *irec, /* btree record */
95 int *stat) /* output: success/failure */
96 {
97 union xfs_btree_rec *rec;
98 int error;
99
100 error = xfs_btree_get_rec(cur, &rec, stat);
101 if (!error && *stat == 1) {
102 irec->ir_startino = be32_to_cpu(rec->inobt.ir_startino);
103 irec->ir_freecount = be32_to_cpu(rec->inobt.ir_freecount);
104 irec->ir_free = be64_to_cpu(rec->inobt.ir_free);
105 }
106 return error;
107 }
108
109 /*
110 * Verify that the number of free inodes in the AGI is correct.
111 */
112 #ifdef DEBUG
113 STATIC int
114 xfs_check_agi_freecount(
115 struct xfs_btree_cur *cur,
116 struct xfs_agi *agi)
117 {
118 if (cur->bc_nlevels == 1) {
119 xfs_inobt_rec_incore_t rec;
120 int freecount = 0;
121 int error;
122 int i;
123
124 error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
125 if (error)
126 return error;
127
128 do {
129 error = xfs_inobt_get_rec(cur, &rec, &i);
130 if (error)
131 return error;
132
133 if (i) {
134 freecount += rec.ir_freecount;
135 error = xfs_btree_increment(cur, 0, &i);
136 if (error)
137 return error;
138 }
139 } while (i == 1);
140
141 if (!XFS_FORCED_SHUTDOWN(cur->bc_mp))
142 ASSERT(freecount == be32_to_cpu(agi->agi_freecount));
143 }
144 return 0;
145 }
146 #else
147 #define xfs_check_agi_freecount(cur, agi) 0
148 #endif
149
150 /*
151 * Initialise a new set of inodes.
152 */
153 STATIC int
154 xfs_ialloc_inode_init(
155 struct xfs_mount *mp,
156 struct xfs_trans *tp,
157 xfs_agnumber_t agno,
158 xfs_agblock_t agbno,
159 xfs_agblock_t length,
160 unsigned int gen)
161 {
162 struct xfs_buf *fbuf;
163 struct xfs_dinode *free;
164 int blks_per_cluster, nbufs, ninodes;
165 int version;
166 int i, j;
167 xfs_daddr_t d;
168
169 /*
170 * Loop over the new block(s), filling in the inodes.
171 * For small block sizes, manipulate the inodes in buffers
172 * which are multiples of the blocks size.
173 */
174 if (mp->m_sb.sb_blocksize >= XFS_INODE_CLUSTER_SIZE(mp)) {
175 blks_per_cluster = 1;
176 nbufs = length;
177 ninodes = mp->m_sb.sb_inopblock;
178 } else {
179 blks_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) /
180 mp->m_sb.sb_blocksize;
181 nbufs = length / blks_per_cluster;
182 ninodes = blks_per_cluster * mp->m_sb.sb_inopblock;
183 }
184
185 /*
186 * Figure out what version number to use in the inodes we create.
187 * If the superblock version has caught up to the one that supports
188 * the new inode format, then use the new inode version. Otherwise
189 * use the old version so that old kernels will continue to be
190 * able to use the file system.
191 */
192 if (xfs_sb_version_hasnlink(&mp->m_sb))
193 version = 2;
194 else
195 version = 1;
196
197 for (j = 0; j < nbufs; j++) {
198 /*
199 * Get the block.
200 */
201 d = XFS_AGB_TO_DADDR(mp, agno, agbno + (j * blks_per_cluster));
202 fbuf = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
203 mp->m_bsize * blks_per_cluster,
204 XBF_LOCK);
205 if (!fbuf)
206 return ENOMEM;
207 /*
208 * Initialize all inodes in this buffer and then log them.
209 *
210 * XXX: It would be much better if we had just one transaction
211 * to log a whole cluster of inodes instead of all the
212 * individual transactions causing a lot of log traffic.
213 */
214 xfs_buf_zero(fbuf, 0, ninodes << mp->m_sb.sb_inodelog);
215 for (i = 0; i < ninodes; i++) {
216 int ioffset = i << mp->m_sb.sb_inodelog;
217 uint isize = sizeof(struct xfs_dinode);
218
219 free = xfs_make_iptr(mp, fbuf, i);
220 free->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
221 free->di_version = version;
222 free->di_gen = cpu_to_be32(gen);
223 free->di_next_unlinked = cpu_to_be32(NULLAGINO);
224 xfs_trans_log_buf(tp, fbuf, ioffset, ioffset + isize - 1);
225 }
226 xfs_trans_inode_alloc_buf(tp, fbuf);
227 }
228 return 0;
229 }
230
231 /*
232 * Allocate new inodes in the allocation group specified by agbp.
233 * Return 0 for success, else error code.
234 */
235 STATIC int /* error code or 0 */
236 xfs_ialloc_ag_alloc(
237 xfs_trans_t *tp, /* transaction pointer */
238 xfs_buf_t *agbp, /* alloc group buffer */
239 int *alloc)
240 {
241 xfs_agi_t *agi; /* allocation group header */
242 xfs_alloc_arg_t args; /* allocation argument structure */
243 xfs_btree_cur_t *cur; /* inode btree cursor */
244 xfs_agnumber_t agno;
245 int error;
246 int i;
247 xfs_agino_t newino; /* new first inode's number */
248 xfs_agino_t newlen; /* new number of inodes */
249 xfs_agino_t thisino; /* current inode number, for loop */
250 int isaligned = 0; /* inode allocation at stripe unit */
251 /* boundary */
252 struct xfs_perag *pag;
253
254 args.tp = tp;
255 args.mp = tp->t_mountp;
256
257 /*
258 * Locking will ensure that we don't have two callers in here
259 * at one time.
260 */
261 newlen = XFS_IALLOC_INODES(args.mp);
262 if (args.mp->m_maxicount &&
263 args.mp->m_sb.sb_icount + newlen > args.mp->m_maxicount)
264 return XFS_ERROR(ENOSPC);
265 args.minlen = args.maxlen = XFS_IALLOC_BLOCKS(args.mp);
266 /*
267 * First try to allocate inodes contiguous with the last-allocated
268 * chunk of inodes. If the filesystem is striped, this will fill
269 * an entire stripe unit with inodes.
270 */
271 agi = XFS_BUF_TO_AGI(agbp);
272 newino = be32_to_cpu(agi->agi_newino);
273 agno = be32_to_cpu(agi->agi_seqno);
274 args.agbno = XFS_AGINO_TO_AGBNO(args.mp, newino) +
275 XFS_IALLOC_BLOCKS(args.mp);
276 if (likely(newino != NULLAGINO &&
277 (args.agbno < be32_to_cpu(agi->agi_length)))) {
278 args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
279 args.type = XFS_ALLOCTYPE_THIS_BNO;
280 args.mod = args.total = args.wasdel = args.isfl =
281 args.userdata = args.minalignslop = 0;
282 args.prod = 1;
283
284 /*
285 * We need to take into account alignment here to ensure that
286 * we don't modify the free list if we fail to have an exact
287 * block. If we don't have an exact match, and every oher
288 * attempt allocation attempt fails, we'll end up cancelling
289 * a dirty transaction and shutting down.
290 *
291 * For an exact allocation, alignment must be 1,
292 * however we need to take cluster alignment into account when
293 * fixing up the freelist. Use the minalignslop field to
294 * indicate that extra blocks might be required for alignment,
295 * but not to use them in the actual exact allocation.
296 */
297 args.alignment = 1;
298 args.minalignslop = xfs_ialloc_cluster_alignment(&args) - 1;
299
300 /* Allow space for the inode btree to split. */
301 args.minleft = args.mp->m_in_maxlevels - 1;
302 if ((error = xfs_alloc_vextent(&args)))
303 return error;
304 } else
305 args.fsbno = NULLFSBLOCK;
306
307 if (unlikely(args.fsbno == NULLFSBLOCK)) {
308 /*
309 * Set the alignment for the allocation.
310 * If stripe alignment is turned on then align at stripe unit
311 * boundary.
312 * If the cluster size is smaller than a filesystem block
313 * then we're doing I/O for inodes in filesystem block size
314 * pieces, so don't need alignment anyway.
315 */
316 isaligned = 0;
317 if (args.mp->m_sinoalign) {
318 ASSERT(!(args.mp->m_flags & XFS_MOUNT_NOALIGN));
319 args.alignment = args.mp->m_dalign;
320 isaligned = 1;
321 } else
322 args.alignment = xfs_ialloc_cluster_alignment(&args);
323 /*
324 * Need to figure out where to allocate the inode blocks.
325 * Ideally they should be spaced out through the a.g.
326 * For now, just allocate blocks up front.
327 */
328 args.agbno = be32_to_cpu(agi->agi_root);
329 args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
330 /*
331 * Allocate a fixed-size extent of inodes.
332 */
333 args.type = XFS_ALLOCTYPE_NEAR_BNO;
334 args.mod = args.total = args.wasdel = args.isfl =
335 args.userdata = args.minalignslop = 0;
336 args.prod = 1;
337 /*
338 * Allow space for the inode btree to split.
339 */
340 args.minleft = args.mp->m_in_maxlevels - 1;
341 if ((error = xfs_alloc_vextent(&args)))
342 return error;
343 }
344
345 /*
346 * If stripe alignment is turned on, then try again with cluster
347 * alignment.
348 */
349 if (isaligned && args.fsbno == NULLFSBLOCK) {
350 args.type = XFS_ALLOCTYPE_NEAR_BNO;
351 args.agbno = be32_to_cpu(agi->agi_root);
352 args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
353 args.alignment = xfs_ialloc_cluster_alignment(&args);
354 if ((error = xfs_alloc_vextent(&args)))
355 return error;
356 }
357
358 if (args.fsbno == NULLFSBLOCK) {
359 *alloc = 0;
360 return 0;
361 }
362 ASSERT(args.len == args.minlen);
363
364 /*
365 * Stamp and write the inode buffers.
366 *
367 * Seed the new inode cluster with a random generation number. This
368 * prevents short-term reuse of generation numbers if a chunk is
369 * freed and then immediately reallocated. We use random numbers
370 * rather than a linear progression to prevent the next generation
371 * number from being easily guessable.
372 */
373 error = xfs_ialloc_inode_init(args.mp, tp, agno, args.agbno,
374 args.len, random32());
375
376 if (error)
377 return error;
378 /*
379 * Convert the results.
380 */
381 newino = XFS_OFFBNO_TO_AGINO(args.mp, args.agbno, 0);
382 be32_add_cpu(&agi->agi_count, newlen);
383 be32_add_cpu(&agi->agi_freecount, newlen);
384 pag = xfs_perag_get(args.mp, agno);
385 pag->pagi_freecount += newlen;
386 xfs_perag_put(pag);
387 agi->agi_newino = cpu_to_be32(newino);
388
389 /*
390 * Insert records describing the new inode chunk into the btree.
391 */
392 cur = xfs_inobt_init_cursor(args.mp, tp, agbp, agno);
393 for (thisino = newino;
394 thisino < newino + newlen;
395 thisino += XFS_INODES_PER_CHUNK) {
396 cur->bc_rec.i.ir_startino = thisino;
397 cur->bc_rec.i.ir_freecount = XFS_INODES_PER_CHUNK;
398 cur->bc_rec.i.ir_free = XFS_INOBT_ALL_FREE;
399 error = xfs_btree_lookup(cur, XFS_LOOKUP_EQ, &i);
400 if (error) {
401 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
402 return error;
403 }
404 ASSERT(i == 0);
405 error = xfs_btree_insert(cur, &i);
406 if (error) {
407 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
408 return error;
409 }
410 ASSERT(i == 1);
411 }
412 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
413 /*
414 * Log allocation group header fields
415 */
416 xfs_ialloc_log_agi(tp, agbp,
417 XFS_AGI_COUNT | XFS_AGI_FREECOUNT | XFS_AGI_NEWINO);
418 /*
419 * Modify/log superblock values for inode count and inode free count.
420 */
421 xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, (long)newlen);
422 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, (long)newlen);
423 *alloc = 1;
424 return 0;
425 }
426
427 STATIC xfs_agnumber_t
428 xfs_ialloc_next_ag(
429 xfs_mount_t *mp)
430 {
431 xfs_agnumber_t agno;
432
433 spin_lock(&mp->m_agirotor_lock);
434 agno = mp->m_agirotor;
435 if (++mp->m_agirotor == mp->m_maxagi)
436 mp->m_agirotor = 0;
437 spin_unlock(&mp->m_agirotor_lock);
438
439 return agno;
440 }
441
442 /*
443 * Select an allocation group to look for a free inode in, based on the parent
444 * inode and then mode. Return the allocation group buffer.
445 */
446 STATIC xfs_buf_t * /* allocation group buffer */
447 xfs_ialloc_ag_select(
448 xfs_trans_t *tp, /* transaction pointer */
449 xfs_ino_t parent, /* parent directory inode number */
450 umode_t mode, /* bits set to indicate file type */
451 int okalloc) /* ok to allocate more space */
452 {
453 xfs_buf_t *agbp; /* allocation group header buffer */
454 xfs_agnumber_t agcount; /* number of ag's in the filesystem */
455 xfs_agnumber_t agno; /* current ag number */
456 int flags; /* alloc buffer locking flags */
457 xfs_extlen_t ineed; /* blocks needed for inode allocation */
458 xfs_extlen_t longest = 0; /* longest extent available */
459 xfs_mount_t *mp; /* mount point structure */
460 int needspace; /* file mode implies space allocated */
461 xfs_perag_t *pag; /* per allocation group data */
462 xfs_agnumber_t pagno; /* parent (starting) ag number */
463
464 /*
465 * Files of these types need at least one block if length > 0
466 * (and they won't fit in the inode, but that's hard to figure out).
467 */
468 needspace = S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode);
469 mp = tp->t_mountp;
470 agcount = mp->m_maxagi;
471 if (S_ISDIR(mode))
472 pagno = xfs_ialloc_next_ag(mp);
473 else {
474 pagno = XFS_INO_TO_AGNO(mp, parent);
475 if (pagno >= agcount)
476 pagno = 0;
477 }
478 ASSERT(pagno < agcount);
479 /*
480 * Loop through allocation groups, looking for one with a little
481 * free space in it. Note we don't look for free inodes, exactly.
482 * Instead, we include whether there is a need to allocate inodes
483 * to mean that blocks must be allocated for them,
484 * if none are currently free.
485 */
486 agno = pagno;
487 flags = XFS_ALLOC_FLAG_TRYLOCK;
488 for (;;) {
489 pag = xfs_perag_get(mp, agno);
490 if (!pag->pagi_init) {
491 if (xfs_ialloc_read_agi(mp, tp, agno, &agbp)) {
492 agbp = NULL;
493 goto nextag;
494 }
495 } else
496 agbp = NULL;
497
498 if (!pag->pagi_inodeok) {
499 xfs_ialloc_next_ag(mp);
500 goto unlock_nextag;
501 }
502
503 /*
504 * Is there enough free space for the file plus a block
505 * of inodes (if we need to allocate some)?
506 */
507 ineed = pag->pagi_freecount ? 0 : XFS_IALLOC_BLOCKS(mp);
508 if (ineed && !pag->pagf_init) {
509 if (agbp == NULL &&
510 xfs_ialloc_read_agi(mp, tp, agno, &agbp)) {
511 agbp = NULL;
512 goto nextag;
513 }
514 (void)xfs_alloc_pagf_init(mp, tp, agno, flags);
515 }
516 if (!ineed || pag->pagf_init) {
517 if (ineed && !(longest = pag->pagf_longest))
518 longest = pag->pagf_flcount > 0;
519 if (!ineed ||
520 (pag->pagf_freeblks >= needspace + ineed &&
521 longest >= ineed &&
522 okalloc)) {
523 if (agbp == NULL &&
524 xfs_ialloc_read_agi(mp, tp, agno, &agbp)) {
525 agbp = NULL;
526 goto nextag;
527 }
528 xfs_perag_put(pag);
529 return agbp;
530 }
531 }
532 unlock_nextag:
533 if (agbp)
534 xfs_trans_brelse(tp, agbp);
535 nextag:
536 xfs_perag_put(pag);
537 /*
538 * No point in iterating over the rest, if we're shutting
539 * down.
540 */
541 if (XFS_FORCED_SHUTDOWN(mp))
542 return NULL;
543 agno++;
544 if (agno >= agcount)
545 agno = 0;
546 if (agno == pagno) {
547 if (flags == 0)
548 return NULL;
549 flags = 0;
550 }
551 }
552 }
553
554 /*
555 * Try to retrieve the next record to the left/right from the current one.
556 */
557 STATIC int
558 xfs_ialloc_next_rec(
559 struct xfs_btree_cur *cur,
560 xfs_inobt_rec_incore_t *rec,
561 int *done,
562 int left)
563 {
564 int error;
565 int i;
566
567 if (left)
568 error = xfs_btree_decrement(cur, 0, &i);
569 else
570 error = xfs_btree_increment(cur, 0, &i);
571
572 if (error)
573 return error;
574 *done = !i;
575 if (i) {
576 error = xfs_inobt_get_rec(cur, rec, &i);
577 if (error)
578 return error;
579 XFS_WANT_CORRUPTED_RETURN(i == 1);
580 }
581
582 return 0;
583 }
584
585 STATIC int
586 xfs_ialloc_get_rec(
587 struct xfs_btree_cur *cur,
588 xfs_agino_t agino,
589 xfs_inobt_rec_incore_t *rec,
590 int *done,
591 int left)
592 {
593 int error;
594 int i;
595
596 error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_EQ, &i);
597 if (error)
598 return error;
599 *done = !i;
600 if (i) {
601 error = xfs_inobt_get_rec(cur, rec, &i);
602 if (error)
603 return error;
604 XFS_WANT_CORRUPTED_RETURN(i == 1);
605 }
606
607 return 0;
608 }
609
610 /*
611 * Visible inode allocation functions.
612 */
613
614 /*
615 * Allocate an inode on disk.
616 * Mode is used to tell whether the new inode will need space, and whether
617 * it is a directory.
618 *
619 * The arguments IO_agbp and alloc_done are defined to work within
620 * the constraint of one allocation per transaction.
621 * xfs_dialloc() is designed to be called twice if it has to do an
622 * allocation to make more free inodes. On the first call,
623 * IO_agbp should be set to NULL. If an inode is available,
624 * i.e., xfs_dialloc() did not need to do an allocation, an inode
625 * number is returned. In this case, IO_agbp would be set to the
626 * current ag_buf and alloc_done set to false.
627 * If an allocation needed to be done, xfs_dialloc would return
628 * the current ag_buf in IO_agbp and set alloc_done to true.
629 * The caller should then commit the current transaction, allocate a new
630 * transaction, and call xfs_dialloc() again, passing in the previous
631 * value of IO_agbp. IO_agbp should be held across the transactions.
632 * Since the agbp is locked across the two calls, the second call is
633 * guaranteed to have a free inode available.
634 *
635 * Once we successfully pick an inode its number is returned and the
636 * on-disk data structures are updated. The inode itself is not read
637 * in, since doing so would break ordering constraints with xfs_reclaim.
638 */
639 int
640 xfs_dialloc(
641 xfs_trans_t *tp, /* transaction pointer */
642 xfs_ino_t parent, /* parent inode (directory) */
643 umode_t mode, /* mode bits for new inode */
644 int okalloc, /* ok to allocate more space */
645 xfs_buf_t **IO_agbp, /* in/out ag header's buffer */
646 boolean_t *alloc_done, /* true if we needed to replenish
647 inode freelist */
648 xfs_ino_t *inop) /* inode number allocated */
649 {
650 xfs_agnumber_t agcount; /* number of allocation groups */
651 xfs_buf_t *agbp; /* allocation group header's buffer */
652 xfs_agnumber_t agno; /* allocation group number */
653 xfs_agi_t *agi; /* allocation group header structure */
654 xfs_btree_cur_t *cur; /* inode allocation btree cursor */
655 int error; /* error return value */
656 int i; /* result code */
657 int ialloced; /* inode allocation status */
658 int noroom = 0; /* no space for inode blk allocation */
659 xfs_ino_t ino; /* fs-relative inode to be returned */
660 /* REFERENCED */
661 int j; /* result code */
662 xfs_mount_t *mp; /* file system mount structure */
663 int offset; /* index of inode in chunk */
664 xfs_agino_t pagino; /* parent's AG relative inode # */
665 xfs_agnumber_t pagno; /* parent's AG number */
666 xfs_inobt_rec_incore_t rec; /* inode allocation record */
667 xfs_agnumber_t tagno; /* testing allocation group number */
668 xfs_btree_cur_t *tcur; /* temp cursor */
669 xfs_inobt_rec_incore_t trec; /* temp inode allocation record */
670 struct xfs_perag *pag;
671
672
673 if (*IO_agbp == NULL) {
674 /*
675 * We do not have an agbp, so select an initial allocation
676 * group for inode allocation.
677 */
678 agbp = xfs_ialloc_ag_select(tp, parent, mode, okalloc);
679 /*
680 * Couldn't find an allocation group satisfying the
681 * criteria, give up.
682 */
683 if (!agbp) {
684 *inop = NULLFSINO;
685 return 0;
686 }
687 agi = XFS_BUF_TO_AGI(agbp);
688 ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
689 } else {
690 /*
691 * Continue where we left off before. In this case, we
692 * know that the allocation group has free inodes.
693 */
694 agbp = *IO_agbp;
695 agi = XFS_BUF_TO_AGI(agbp);
696 ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
697 ASSERT(be32_to_cpu(agi->agi_freecount) > 0);
698 }
699 mp = tp->t_mountp;
700 agcount = mp->m_sb.sb_agcount;
701 agno = be32_to_cpu(agi->agi_seqno);
702 tagno = agno;
703 pagno = XFS_INO_TO_AGNO(mp, parent);
704 pagino = XFS_INO_TO_AGINO(mp, parent);
705
706 /*
707 * If we have already hit the ceiling of inode blocks then clear
708 * okalloc so we scan all available agi structures for a free
709 * inode.
710 */
711
712 if (mp->m_maxicount &&
713 mp->m_sb.sb_icount + XFS_IALLOC_INODES(mp) > mp->m_maxicount) {
714 noroom = 1;
715 okalloc = 0;
716 }
717
718 /*
719 * Loop until we find an allocation group that either has free inodes
720 * or in which we can allocate some inodes. Iterate through the
721 * allocation groups upward, wrapping at the end.
722 */
723 *alloc_done = B_FALSE;
724 while (!agi->agi_freecount) {
725 /*
726 * Don't do anything if we're not supposed to allocate
727 * any blocks, just go on to the next ag.
728 */
729 if (okalloc) {
730 /*
731 * Try to allocate some new inodes in the allocation
732 * group.
733 */
734 if ((error = xfs_ialloc_ag_alloc(tp, agbp, &ialloced))) {
735 xfs_trans_brelse(tp, agbp);
736 if (error == ENOSPC) {
737 *inop = NULLFSINO;
738 return 0;
739 } else
740 return error;
741 }
742 if (ialloced) {
743 /*
744 * We successfully allocated some inodes, return
745 * the current context to the caller so that it
746 * can commit the current transaction and call
747 * us again where we left off.
748 */
749 ASSERT(be32_to_cpu(agi->agi_freecount) > 0);
750 *alloc_done = B_TRUE;
751 *IO_agbp = agbp;
752 *inop = NULLFSINO;
753 return 0;
754 }
755 }
756 /*
757 * If it failed, give up on this ag.
758 */
759 xfs_trans_brelse(tp, agbp);
760 /*
761 * Go on to the next ag: get its ag header.
762 */
763 nextag:
764 if (++tagno == agcount)
765 tagno = 0;
766 if (tagno == agno) {
767 *inop = NULLFSINO;
768 return noroom ? ENOSPC : 0;
769 }
770 pag = xfs_perag_get(mp, tagno);
771 if (pag->pagi_inodeok == 0) {
772 xfs_perag_put(pag);
773 goto nextag;
774 }
775 error = xfs_ialloc_read_agi(mp, tp, tagno, &agbp);
776 xfs_perag_put(pag);
777 if (error)
778 goto nextag;
779 agi = XFS_BUF_TO_AGI(agbp);
780 ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
781 }
782 /*
783 * Here with an allocation group that has a free inode.
784 * Reset agno since we may have chosen a new ag in the
785 * loop above.
786 */
787 agno = tagno;
788 *IO_agbp = NULL;
789 pag = xfs_perag_get(mp, agno);
790
791 restart_pagno:
792 cur = xfs_inobt_init_cursor(mp, tp, agbp, be32_to_cpu(agi->agi_seqno));
793 /*
794 * If pagino is 0 (this is the root inode allocation) use newino.
795 * This must work because we've just allocated some.
796 */
797 if (!pagino)
798 pagino = be32_to_cpu(agi->agi_newino);
799
800 error = xfs_check_agi_freecount(cur, agi);
801 if (error)
802 goto error0;
803
804 /*
805 * If in the same AG as the parent, try to get near the parent.
806 */
807 if (pagno == agno) {
808 int doneleft; /* done, to the left */
809 int doneright; /* done, to the right */
810 int searchdistance = 10;
811
812 error = xfs_inobt_lookup(cur, pagino, XFS_LOOKUP_LE, &i);
813 if (error)
814 goto error0;
815 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
816
817 error = xfs_inobt_get_rec(cur, &rec, &j);
818 if (error)
819 goto error0;
820 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
821
822 if (rec.ir_freecount > 0) {
823 /*
824 * Found a free inode in the same chunk
825 * as the parent, done.
826 */
827 goto alloc_inode;
828 }
829
830
831 /*
832 * In the same AG as parent, but parent's chunk is full.
833 */
834
835 /* duplicate the cursor, search left & right simultaneously */
836 error = xfs_btree_dup_cursor(cur, &tcur);
837 if (error)
838 goto error0;
839
840 /*
841 * Skip to last blocks looked up if same parent inode.
842 */
843 if (pagino != NULLAGINO &&
844 pag->pagl_pagino == pagino &&
845 pag->pagl_leftrec != NULLAGINO &&
846 pag->pagl_rightrec != NULLAGINO) {
847 error = xfs_ialloc_get_rec(tcur, pag->pagl_leftrec,
848 &trec, &doneleft, 1);
849 if (error)
850 goto error1;
851
852 error = xfs_ialloc_get_rec(cur, pag->pagl_rightrec,
853 &rec, &doneright, 0);
854 if (error)
855 goto error1;
856 } else {
857 /* search left with tcur, back up 1 record */
858 error = xfs_ialloc_next_rec(tcur, &trec, &doneleft, 1);
859 if (error)
860 goto error1;
861
862 /* search right with cur, go forward 1 record. */
863 error = xfs_ialloc_next_rec(cur, &rec, &doneright, 0);
864 if (error)
865 goto error1;
866 }
867
868 /*
869 * Loop until we find an inode chunk with a free inode.
870 */
871 while (!doneleft || !doneright) {
872 int useleft; /* using left inode chunk this time */
873
874 if (!--searchdistance) {
875 /*
876 * Not in range - save last search
877 * location and allocate a new inode
878 */
879 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
880 pag->pagl_leftrec = trec.ir_startino;
881 pag->pagl_rightrec = rec.ir_startino;
882 pag->pagl_pagino = pagino;
883 goto newino;
884 }
885
886 /* figure out the closer block if both are valid. */
887 if (!doneleft && !doneright) {
888 useleft = pagino -
889 (trec.ir_startino + XFS_INODES_PER_CHUNK - 1) <
890 rec.ir_startino - pagino;
891 } else {
892 useleft = !doneleft;
893 }
894
895 /* free inodes to the left? */
896 if (useleft && trec.ir_freecount) {
897 rec = trec;
898 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
899 cur = tcur;
900
901 pag->pagl_leftrec = trec.ir_startino;
902 pag->pagl_rightrec = rec.ir_startino;
903 pag->pagl_pagino = pagino;
904 goto alloc_inode;
905 }
906
907 /* free inodes to the right? */
908 if (!useleft && rec.ir_freecount) {
909 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
910
911 pag->pagl_leftrec = trec.ir_startino;
912 pag->pagl_rightrec = rec.ir_startino;
913 pag->pagl_pagino = pagino;
914 goto alloc_inode;
915 }
916
917 /* get next record to check */
918 if (useleft) {
919 error = xfs_ialloc_next_rec(tcur, &trec,
920 &doneleft, 1);
921 } else {
922 error = xfs_ialloc_next_rec(cur, &rec,
923 &doneright, 0);
924 }
925 if (error)
926 goto error1;
927 }
928
929 /*
930 * We've reached the end of the btree. because
931 * we are only searching a small chunk of the
932 * btree each search, there is obviously free
933 * inodes closer to the parent inode than we
934 * are now. restart the search again.
935 */
936 pag->pagl_pagino = NULLAGINO;
937 pag->pagl_leftrec = NULLAGINO;
938 pag->pagl_rightrec = NULLAGINO;
939 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
940 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
941 goto restart_pagno;
942 }
943
944 /*
945 * In a different AG from the parent.
946 * See if the most recently allocated block has any free.
947 */
948 newino:
949 if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
950 error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
951 XFS_LOOKUP_EQ, &i);
952 if (error)
953 goto error0;
954
955 if (i == 1) {
956 error = xfs_inobt_get_rec(cur, &rec, &j);
957 if (error)
958 goto error0;
959
960 if (j == 1 && rec.ir_freecount > 0) {
961 /*
962 * The last chunk allocated in the group
963 * still has a free inode.
964 */
965 goto alloc_inode;
966 }
967 }
968 }
969
970 /*
971 * None left in the last group, search the whole AG
972 */
973 error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
974 if (error)
975 goto error0;
976 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
977
978 for (;;) {
979 error = xfs_inobt_get_rec(cur, &rec, &i);
980 if (error)
981 goto error0;
982 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
983 if (rec.ir_freecount > 0)
984 break;
985 error = xfs_btree_increment(cur, 0, &i);
986 if (error)
987 goto error0;
988 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
989 }
990
991 alloc_inode:
992 offset = xfs_ialloc_find_free(&rec.ir_free);
993 ASSERT(offset >= 0);
994 ASSERT(offset < XFS_INODES_PER_CHUNK);
995 ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
996 XFS_INODES_PER_CHUNK) == 0);
997 ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino + offset);
998 rec.ir_free &= ~XFS_INOBT_MASK(offset);
999 rec.ir_freecount--;
1000 error = xfs_inobt_update(cur, &rec);
1001 if (error)
1002 goto error0;
1003 be32_add_cpu(&agi->agi_freecount, -1);
1004 xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1005 pag->pagi_freecount--;
1006
1007 error = xfs_check_agi_freecount(cur, agi);
1008 if (error)
1009 goto error0;
1010
1011 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1012 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1013 xfs_perag_put(pag);
1014 *inop = ino;
1015 return 0;
1016 error1:
1017 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
1018 error0:
1019 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1020 xfs_perag_put(pag);
1021 return error;
1022 }
1023
1024 /*
1025 * Free disk inode. Carefully avoids touching the incore inode, all
1026 * manipulations incore are the caller's responsibility.
1027 * The on-disk inode is not changed by this operation, only the
1028 * btree (free inode mask) is changed.
1029 */
1030 int
1031 xfs_difree(
1032 xfs_trans_t *tp, /* transaction pointer */
1033 xfs_ino_t inode, /* inode to be freed */
1034 xfs_bmap_free_t *flist, /* extents to free */
1035 int *delete, /* set if inode cluster was deleted */
1036 xfs_ino_t *first_ino) /* first inode in deleted cluster */
1037 {
1038 /* REFERENCED */
1039 xfs_agblock_t agbno; /* block number containing inode */
1040 xfs_buf_t *agbp; /* buffer containing allocation group header */
1041 xfs_agino_t agino; /* inode number relative to allocation group */
1042 xfs_agnumber_t agno; /* allocation group number */
1043 xfs_agi_t *agi; /* allocation group header */
1044 xfs_btree_cur_t *cur; /* inode btree cursor */
1045 int error; /* error return value */
1046 int i; /* result code */
1047 int ilen; /* inodes in an inode cluster */
1048 xfs_mount_t *mp; /* mount structure for filesystem */
1049 int off; /* offset of inode in inode chunk */
1050 xfs_inobt_rec_incore_t rec; /* btree record */
1051 struct xfs_perag *pag;
1052
1053 mp = tp->t_mountp;
1054
1055 /*
1056 * Break up inode number into its components.
1057 */
1058 agno = XFS_INO_TO_AGNO(mp, inode);
1059 if (agno >= mp->m_sb.sb_agcount) {
1060 xfs_warn(mp, "%s: agno >= mp->m_sb.sb_agcount (%d >= %d).",
1061 __func__, agno, mp->m_sb.sb_agcount);
1062 ASSERT(0);
1063 return XFS_ERROR(EINVAL);
1064 }
1065 agino = XFS_INO_TO_AGINO(mp, inode);
1066 if (inode != XFS_AGINO_TO_INO(mp, agno, agino)) {
1067 xfs_warn(mp, "%s: inode != XFS_AGINO_TO_INO() (%llu != %llu).",
1068 __func__, (unsigned long long)inode,
1069 (unsigned long long)XFS_AGINO_TO_INO(mp, agno, agino));
1070 ASSERT(0);
1071 return XFS_ERROR(EINVAL);
1072 }
1073 agbno = XFS_AGINO_TO_AGBNO(mp, agino);
1074 if (agbno >= mp->m_sb.sb_agblocks) {
1075 xfs_warn(mp, "%s: agbno >= mp->m_sb.sb_agblocks (%d >= %d).",
1076 __func__, agbno, mp->m_sb.sb_agblocks);
1077 ASSERT(0);
1078 return XFS_ERROR(EINVAL);
1079 }
1080 /*
1081 * Get the allocation group header.
1082 */
1083 error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
1084 if (error) {
1085 xfs_warn(mp, "%s: xfs_ialloc_read_agi() returned error %d.",
1086 __func__, error);
1087 return error;
1088 }
1089 agi = XFS_BUF_TO_AGI(agbp);
1090 ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
1091 ASSERT(agbno < be32_to_cpu(agi->agi_length));
1092 /*
1093 * Initialize the cursor.
1094 */
1095 cur = xfs_inobt_init_cursor(mp, tp, agbp, agno);
1096
1097 error = xfs_check_agi_freecount(cur, agi);
1098 if (error)
1099 goto error0;
1100
1101 /*
1102 * Look for the entry describing this inode.
1103 */
1104 if ((error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i))) {
1105 xfs_warn(mp, "%s: xfs_inobt_lookup() returned error %d.",
1106 __func__, error);
1107 goto error0;
1108 }
1109 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1110 error = xfs_inobt_get_rec(cur, &rec, &i);
1111 if (error) {
1112 xfs_warn(mp, "%s: xfs_inobt_get_rec() returned error %d.",
1113 __func__, error);
1114 goto error0;
1115 }
1116 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1117 /*
1118 * Get the offset in the inode chunk.
1119 */
1120 off = agino - rec.ir_startino;
1121 ASSERT(off >= 0 && off < XFS_INODES_PER_CHUNK);
1122 ASSERT(!(rec.ir_free & XFS_INOBT_MASK(off)));
1123 /*
1124 * Mark the inode free & increment the count.
1125 */
1126 rec.ir_free |= XFS_INOBT_MASK(off);
1127 rec.ir_freecount++;
1128
1129 /*
1130 * When an inode cluster is free, it becomes eligible for removal
1131 */
1132 if (!(mp->m_flags & XFS_MOUNT_IKEEP) &&
1133 (rec.ir_freecount == XFS_IALLOC_INODES(mp))) {
1134
1135 *delete = 1;
1136 *first_ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino);
1137
1138 /*
1139 * Remove the inode cluster from the AGI B+Tree, adjust the
1140 * AGI and Superblock inode counts, and mark the disk space
1141 * to be freed when the transaction is committed.
1142 */
1143 ilen = XFS_IALLOC_INODES(mp);
1144 be32_add_cpu(&agi->agi_count, -ilen);
1145 be32_add_cpu(&agi->agi_freecount, -(ilen - 1));
1146 xfs_ialloc_log_agi(tp, agbp, XFS_AGI_COUNT | XFS_AGI_FREECOUNT);
1147 pag = xfs_perag_get(mp, agno);
1148 pag->pagi_freecount -= ilen - 1;
1149 xfs_perag_put(pag);
1150 xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, -ilen);
1151 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -(ilen - 1));
1152
1153 if ((error = xfs_btree_delete(cur, &i))) {
1154 xfs_warn(mp, "%s: xfs_btree_delete returned error %d.",
1155 __func__, error);
1156 goto error0;
1157 }
1158
1159 xfs_bmap_add_free(XFS_AGB_TO_FSB(mp,
1160 agno, XFS_INO_TO_AGBNO(mp,rec.ir_startino)),
1161 XFS_IALLOC_BLOCKS(mp), flist, mp);
1162 } else {
1163 *delete = 0;
1164
1165 error = xfs_inobt_update(cur, &rec);
1166 if (error) {
1167 xfs_warn(mp, "%s: xfs_inobt_update returned error %d.",
1168 __func__, error);
1169 goto error0;
1170 }
1171
1172 /*
1173 * Change the inode free counts and log the ag/sb changes.
1174 */
1175 be32_add_cpu(&agi->agi_freecount, 1);
1176 xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1177 pag = xfs_perag_get(mp, agno);
1178 pag->pagi_freecount++;
1179 xfs_perag_put(pag);
1180 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, 1);
1181 }
1182
1183 error = xfs_check_agi_freecount(cur, agi);
1184 if (error)
1185 goto error0;
1186
1187 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1188 return 0;
1189
1190 error0:
1191 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1192 return error;
1193 }
1194
1195 STATIC int
1196 xfs_imap_lookup(
1197 struct xfs_mount *mp,
1198 struct xfs_trans *tp,
1199 xfs_agnumber_t agno,
1200 xfs_agino_t agino,
1201 xfs_agblock_t agbno,
1202 xfs_agblock_t *chunk_agbno,
1203 xfs_agblock_t *offset_agbno,
1204 int flags)
1205 {
1206 struct xfs_inobt_rec_incore rec;
1207 struct xfs_btree_cur *cur;
1208 struct xfs_buf *agbp;
1209 int error;
1210 int i;
1211
1212 error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
1213 if (error) {
1214 xfs_alert(mp,
1215 "%s: xfs_ialloc_read_agi() returned error %d, agno %d",
1216 __func__, error, agno);
1217 return error;
1218 }
1219
1220 /*
1221 * Lookup the inode record for the given agino. If the record cannot be
1222 * found, then it's an invalid inode number and we should abort. Once
1223 * we have a record, we need to ensure it contains the inode number
1224 * we are looking up.
1225 */
1226 cur = xfs_inobt_init_cursor(mp, tp, agbp, agno);
1227 error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i);
1228 if (!error) {
1229 if (i)
1230 error = xfs_inobt_get_rec(cur, &rec, &i);
1231 if (!error && i == 0)
1232 error = EINVAL;
1233 }
1234
1235 xfs_trans_brelse(tp, agbp);
1236 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1237 if (error)
1238 return error;
1239
1240 /* check that the returned record contains the required inode */
1241 if (rec.ir_startino > agino ||
1242 rec.ir_startino + XFS_IALLOC_INODES(mp) <= agino)
1243 return EINVAL;
1244
1245 /* for untrusted inodes check it is allocated first */
1246 if ((flags & XFS_IGET_UNTRUSTED) &&
1247 (rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino)))
1248 return EINVAL;
1249
1250 *chunk_agbno = XFS_AGINO_TO_AGBNO(mp, rec.ir_startino);
1251 *offset_agbno = agbno - *chunk_agbno;
1252 return 0;
1253 }
1254
1255 /*
1256 * Return the location of the inode in imap, for mapping it into a buffer.
1257 */
1258 int
1259 xfs_imap(
1260 xfs_mount_t *mp, /* file system mount structure */
1261 xfs_trans_t *tp, /* transaction pointer */
1262 xfs_ino_t ino, /* inode to locate */
1263 struct xfs_imap *imap, /* location map structure */
1264 uint flags) /* flags for inode btree lookup */
1265 {
1266 xfs_agblock_t agbno; /* block number of inode in the alloc group */
1267 xfs_agino_t agino; /* inode number within alloc group */
1268 xfs_agnumber_t agno; /* allocation group number */
1269 int blks_per_cluster; /* num blocks per inode cluster */
1270 xfs_agblock_t chunk_agbno; /* first block in inode chunk */
1271 xfs_agblock_t cluster_agbno; /* first block in inode cluster */
1272 int error; /* error code */
1273 int offset; /* index of inode in its buffer */
1274 int offset_agbno; /* blks from chunk start to inode */
1275
1276 ASSERT(ino != NULLFSINO);
1277
1278 /*
1279 * Split up the inode number into its parts.
1280 */
1281 agno = XFS_INO_TO_AGNO(mp, ino);
1282 agino = XFS_INO_TO_AGINO(mp, ino);
1283 agbno = XFS_AGINO_TO_AGBNO(mp, agino);
1284 if (agno >= mp->m_sb.sb_agcount || agbno >= mp->m_sb.sb_agblocks ||
1285 ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
1286 #ifdef DEBUG
1287 /*
1288 * Don't output diagnostic information for untrusted inodes
1289 * as they can be invalid without implying corruption.
1290 */
1291 if (flags & XFS_IGET_UNTRUSTED)
1292 return XFS_ERROR(EINVAL);
1293 if (agno >= mp->m_sb.sb_agcount) {
1294 xfs_alert(mp,
1295 "%s: agno (%d) >= mp->m_sb.sb_agcount (%d)",
1296 __func__, agno, mp->m_sb.sb_agcount);
1297 }
1298 if (agbno >= mp->m_sb.sb_agblocks) {
1299 xfs_alert(mp,
1300 "%s: agbno (0x%llx) >= mp->m_sb.sb_agblocks (0x%lx)",
1301 __func__, (unsigned long long)agbno,
1302 (unsigned long)mp->m_sb.sb_agblocks);
1303 }
1304 if (ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
1305 xfs_alert(mp,
1306 "%s: ino (0x%llx) != XFS_AGINO_TO_INO() (0x%llx)",
1307 __func__, ino,
1308 XFS_AGINO_TO_INO(mp, agno, agino));
1309 }
1310 xfs_stack_trace();
1311 #endif /* DEBUG */
1312 return XFS_ERROR(EINVAL);
1313 }
1314
1315 blks_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_blocklog;
1316
1317 /*
1318 * For bulkstat and handle lookups, we have an untrusted inode number
1319 * that we have to verify is valid. We cannot do this just by reading
1320 * the inode buffer as it may have been unlinked and removed leaving
1321 * inodes in stale state on disk. Hence we have to do a btree lookup
1322 * in all cases where an untrusted inode number is passed.
1323 */
1324 if (flags & XFS_IGET_UNTRUSTED) {
1325 error = xfs_imap_lookup(mp, tp, agno, agino, agbno,
1326 &chunk_agbno, &offset_agbno, flags);
1327 if (error)
1328 return error;
1329 goto out_map;
1330 }
1331
1332 /*
1333 * If the inode cluster size is the same as the blocksize or
1334 * smaller we get to the buffer by simple arithmetics.
1335 */
1336 if (XFS_INODE_CLUSTER_SIZE(mp) <= mp->m_sb.sb_blocksize) {
1337 offset = XFS_INO_TO_OFFSET(mp, ino);
1338 ASSERT(offset < mp->m_sb.sb_inopblock);
1339
1340 imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, agbno);
1341 imap->im_len = XFS_FSB_TO_BB(mp, 1);
1342 imap->im_boffset = (ushort)(offset << mp->m_sb.sb_inodelog);
1343 return 0;
1344 }
1345
1346 /*
1347 * If the inode chunks are aligned then use simple maths to
1348 * find the location. Otherwise we have to do a btree
1349 * lookup to find the location.
1350 */
1351 if (mp->m_inoalign_mask) {
1352 offset_agbno = agbno & mp->m_inoalign_mask;
1353 chunk_agbno = agbno - offset_agbno;
1354 } else {
1355 error = xfs_imap_lookup(mp, tp, agno, agino, agbno,
1356 &chunk_agbno, &offset_agbno, flags);
1357 if (error)
1358 return error;
1359 }
1360
1361 out_map:
1362 ASSERT(agbno >= chunk_agbno);
1363 cluster_agbno = chunk_agbno +
1364 ((offset_agbno / blks_per_cluster) * blks_per_cluster);
1365 offset = ((agbno - cluster_agbno) * mp->m_sb.sb_inopblock) +
1366 XFS_INO_TO_OFFSET(mp, ino);
1367
1368 imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, cluster_agbno);
1369 imap->im_len = XFS_FSB_TO_BB(mp, blks_per_cluster);
1370 imap->im_boffset = (ushort)(offset << mp->m_sb.sb_inodelog);
1371
1372 /*
1373 * If the inode number maps to a block outside the bounds
1374 * of the file system then return NULL rather than calling
1375 * read_buf and panicing when we get an error from the
1376 * driver.
1377 */
1378 if ((imap->im_blkno + imap->im_len) >
1379 XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
1380 xfs_alert(mp,
1381 "%s: (im_blkno (0x%llx) + im_len (0x%llx)) > sb_dblocks (0x%llx)",
1382 __func__, (unsigned long long) imap->im_blkno,
1383 (unsigned long long) imap->im_len,
1384 XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks));
1385 return XFS_ERROR(EINVAL);
1386 }
1387 return 0;
1388 }
1389
1390 /*
1391 * Compute and fill in value of m_in_maxlevels.
1392 */
1393 void
1394 xfs_ialloc_compute_maxlevels(
1395 xfs_mount_t *mp) /* file system mount structure */
1396 {
1397 int level;
1398 uint maxblocks;
1399 uint maxleafents;
1400 int minleafrecs;
1401 int minnoderecs;
1402
1403 maxleafents = (1LL << XFS_INO_AGINO_BITS(mp)) >>
1404 XFS_INODES_PER_CHUNK_LOG;
1405 minleafrecs = mp->m_alloc_mnr[0];
1406 minnoderecs = mp->m_alloc_mnr[1];
1407 maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs;
1408 for (level = 1; maxblocks > 1; level++)
1409 maxblocks = (maxblocks + minnoderecs - 1) / minnoderecs;
1410 mp->m_in_maxlevels = level;
1411 }
1412
1413 /*
1414 * Log specified fields for the ag hdr (inode section)
1415 */
1416 void
1417 xfs_ialloc_log_agi(
1418 xfs_trans_t *tp, /* transaction pointer */
1419 xfs_buf_t *bp, /* allocation group header buffer */
1420 int fields) /* bitmask of fields to log */
1421 {
1422 int first; /* first byte number */
1423 int last; /* last byte number */
1424 static const short offsets[] = { /* field starting offsets */
1425 /* keep in sync with bit definitions */
1426 offsetof(xfs_agi_t, agi_magicnum),
1427 offsetof(xfs_agi_t, agi_versionnum),
1428 offsetof(xfs_agi_t, agi_seqno),
1429 offsetof(xfs_agi_t, agi_length),
1430 offsetof(xfs_agi_t, agi_count),
1431 offsetof(xfs_agi_t, agi_root),
1432 offsetof(xfs_agi_t, agi_level),
1433 offsetof(xfs_agi_t, agi_freecount),
1434 offsetof(xfs_agi_t, agi_newino),
1435 offsetof(xfs_agi_t, agi_dirino),
1436 offsetof(xfs_agi_t, agi_unlinked),
1437 sizeof(xfs_agi_t)
1438 };
1439 #ifdef DEBUG
1440 xfs_agi_t *agi; /* allocation group header */
1441
1442 agi = XFS_BUF_TO_AGI(bp);
1443 ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
1444 #endif
1445 /*
1446 * Compute byte offsets for the first and last fields.
1447 */
1448 xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS, &first, &last);
1449 /*
1450 * Log the allocation group inode header buffer.
1451 */
1452 xfs_trans_log_buf(tp, bp, first, last);
1453 }
1454
1455 #ifdef DEBUG
1456 STATIC void
1457 xfs_check_agi_unlinked(
1458 struct xfs_agi *agi)
1459 {
1460 int i;
1461
1462 for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++)
1463 ASSERT(agi->agi_unlinked[i]);
1464 }
1465 #else
1466 #define xfs_check_agi_unlinked(agi)
1467 #endif
1468
1469 /*
1470 * Read in the allocation group header (inode allocation section)
1471 */
1472 int
1473 xfs_read_agi(
1474 struct xfs_mount *mp, /* file system mount structure */
1475 struct xfs_trans *tp, /* transaction pointer */
1476 xfs_agnumber_t agno, /* allocation group number */
1477 struct xfs_buf **bpp) /* allocation group hdr buf */
1478 {
1479 struct xfs_agi *agi; /* allocation group header */
1480 int agi_ok; /* agi is consistent */
1481 int error;
1482
1483 ASSERT(agno != NULLAGNUMBER);
1484
1485 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
1486 XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
1487 XFS_FSS_TO_BB(mp, 1), 0, bpp);
1488 if (error)
1489 return error;
1490
1491 ASSERT(!xfs_buf_geterror(*bpp));
1492 agi = XFS_BUF_TO_AGI(*bpp);
1493
1494 /*
1495 * Validate the magic number of the agi block.
1496 */
1497 agi_ok = agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC) &&
1498 XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)) &&
1499 be32_to_cpu(agi->agi_seqno) == agno;
1500 if (unlikely(XFS_TEST_ERROR(!agi_ok, mp, XFS_ERRTAG_IALLOC_READ_AGI,
1501 XFS_RANDOM_IALLOC_READ_AGI))) {
1502 XFS_CORRUPTION_ERROR("xfs_read_agi", XFS_ERRLEVEL_LOW,
1503 mp, agi);
1504 xfs_trans_brelse(tp, *bpp);
1505 return XFS_ERROR(EFSCORRUPTED);
1506 }
1507
1508 xfs_buf_set_ref(*bpp, XFS_AGI_REF);
1509
1510 xfs_check_agi_unlinked(agi);
1511 return 0;
1512 }
1513
1514 int
1515 xfs_ialloc_read_agi(
1516 struct xfs_mount *mp, /* file system mount structure */
1517 struct xfs_trans *tp, /* transaction pointer */
1518 xfs_agnumber_t agno, /* allocation group number */
1519 struct xfs_buf **bpp) /* allocation group hdr buf */
1520 {
1521 struct xfs_agi *agi; /* allocation group header */
1522 struct xfs_perag *pag; /* per allocation group data */
1523 int error;
1524
1525 error = xfs_read_agi(mp, tp, agno, bpp);
1526 if (error)
1527 return error;
1528
1529 agi = XFS_BUF_TO_AGI(*bpp);
1530 pag = xfs_perag_get(mp, agno);
1531 if (!pag->pagi_init) {
1532 pag->pagi_freecount = be32_to_cpu(agi->agi_freecount);
1533 pag->pagi_count = be32_to_cpu(agi->agi_count);
1534 pag->pagi_init = 1;
1535 }
1536
1537 /*
1538 * It's possible for these to be out of sync if
1539 * we are in the middle of a forced shutdown.
1540 */
1541 ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) ||
1542 XFS_FORCED_SHUTDOWN(mp));
1543 xfs_perag_put(pag);
1544 return 0;
1545 }
1546
1547 /*
1548 * Read in the agi to initialise the per-ag data in the mount structure
1549 */
1550 int
1551 xfs_ialloc_pagi_init(
1552 xfs_mount_t *mp, /* file system mount structure */
1553 xfs_trans_t *tp, /* transaction pointer */
1554 xfs_agnumber_t agno) /* allocation group number */
1555 {
1556 xfs_buf_t *bp = NULL;
1557 int error;
1558
1559 error = xfs_ialloc_read_agi(mp, tp, agno, &bp);
1560 if (error)
1561 return error;
1562 if (bp)
1563 xfs_trans_brelse(tp, bp);
1564 return 0;
1565 }