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kvm tools, setup: Create private directory
[linux-2.6/next.git] / fs / xfs / xfs_ialloc.c
blob84ebeec16642155d3bf5faf48b3443585504389a
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 void
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 ASSERT(fbuf);
206 ASSERT(!XFS_BUF_GETERROR(fbuf));
207
208 /*
209 * Initialize all inodes in this buffer and then log them.
210 *
211 * XXX: It would be much better if we had just one transaction
212 * to log a whole cluster of inodes instead of all the
213 * individual transactions causing a lot of log traffic.
214 */
215 xfs_buf_zero(fbuf, 0, ninodes << mp->m_sb.sb_inodelog);
216 for (i = 0; i < ninodes; i++) {
217 int ioffset = i << mp->m_sb.sb_inodelog;
218 uint isize = sizeof(struct xfs_dinode);
219
220 free = xfs_make_iptr(mp, fbuf, i);
221 free->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
222 free->di_version = version;
223 free->di_gen = cpu_to_be32(gen);
224 free->di_next_unlinked = cpu_to_be32(NULLAGINO);
225 xfs_trans_log_buf(tp, fbuf, ioffset, ioffset + isize - 1);
226 }
227 xfs_trans_inode_alloc_buf(tp, fbuf);
228 }
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 xfs_ialloc_inode_init(args.mp, tp, agno, args.agbno, args.len,
374 random32());
375
376 /*
377 * Convert the results.
378 */
379 newino = XFS_OFFBNO_TO_AGINO(args.mp, args.agbno, 0);
380 be32_add_cpu(&agi->agi_count, newlen);
381 be32_add_cpu(&agi->agi_freecount, newlen);
382 pag = xfs_perag_get(args.mp, agno);
383 pag->pagi_freecount += newlen;
384 xfs_perag_put(pag);
385 agi->agi_newino = cpu_to_be32(newino);
386
387 /*
388 * Insert records describing the new inode chunk into the btree.
389 */
390 cur = xfs_inobt_init_cursor(args.mp, tp, agbp, agno);
391 for (thisino = newino;
392 thisino < newino + newlen;
393 thisino += XFS_INODES_PER_CHUNK) {
394 cur->bc_rec.i.ir_startino = thisino;
395 cur->bc_rec.i.ir_freecount = XFS_INODES_PER_CHUNK;
396 cur->bc_rec.i.ir_free = XFS_INOBT_ALL_FREE;
397 error = xfs_btree_lookup(cur, XFS_LOOKUP_EQ, &i);
398 if (error) {
399 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
400 return error;
401 }
402 ASSERT(i == 0);
403 error = xfs_btree_insert(cur, &i);
404 if (error) {
405 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
406 return error;
407 }
408 ASSERT(i == 1);
409 }
410 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
411 /*
412 * Log allocation group header fields
413 */
414 xfs_ialloc_log_agi(tp, agbp,
415 XFS_AGI_COUNT | XFS_AGI_FREECOUNT | XFS_AGI_NEWINO);
416 /*
417 * Modify/log superblock values for inode count and inode free count.
418 */
419 xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, (long)newlen);
420 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, (long)newlen);
421 *alloc = 1;
422 return 0;
423 }
424
425 STATIC xfs_agnumber_t
426 xfs_ialloc_next_ag(
427 xfs_mount_t *mp)
428 {
429 xfs_agnumber_t agno;
430
431 spin_lock(&mp->m_agirotor_lock);
432 agno = mp->m_agirotor;
433 if (++mp->m_agirotor == mp->m_maxagi)
434 mp->m_agirotor = 0;
435 spin_unlock(&mp->m_agirotor_lock);
436
437 return agno;
438 }
439
440 /*
441 * Select an allocation group to look for a free inode in, based on the parent
442 * inode and then mode. Return the allocation group buffer.
443 */
444 STATIC xfs_buf_t * /* allocation group buffer */
445 xfs_ialloc_ag_select(
446 xfs_trans_t *tp, /* transaction pointer */
447 xfs_ino_t parent, /* parent directory inode number */
448 mode_t mode, /* bits set to indicate file type */
449 int okalloc) /* ok to allocate more space */
450 {
451 xfs_buf_t *agbp; /* allocation group header buffer */
452 xfs_agnumber_t agcount; /* number of ag's in the filesystem */
453 xfs_agnumber_t agno; /* current ag number */
454 int flags; /* alloc buffer locking flags */
455 xfs_extlen_t ineed; /* blocks needed for inode allocation */
456 xfs_extlen_t longest = 0; /* longest extent available */
457 xfs_mount_t *mp; /* mount point structure */
458 int needspace; /* file mode implies space allocated */
459 xfs_perag_t *pag; /* per allocation group data */
460 xfs_agnumber_t pagno; /* parent (starting) ag number */
461
462 /*
463 * Files of these types need at least one block if length > 0
464 * (and they won't fit in the inode, but that's hard to figure out).
465 */
466 needspace = S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode);
467 mp = tp->t_mountp;
468 agcount = mp->m_maxagi;
469 if (S_ISDIR(mode))
470 pagno = xfs_ialloc_next_ag(mp);
471 else {
472 pagno = XFS_INO_TO_AGNO(mp, parent);
473 if (pagno >= agcount)
474 pagno = 0;
475 }
476 ASSERT(pagno < agcount);
477 /*
478 * Loop through allocation groups, looking for one with a little
479 * free space in it. Note we don't look for free inodes, exactly.
480 * Instead, we include whether there is a need to allocate inodes
481 * to mean that blocks must be allocated for them,
482 * if none are currently free.
483 */
484 agno = pagno;
485 flags = XFS_ALLOC_FLAG_TRYLOCK;
486 for (;;) {
487 pag = xfs_perag_get(mp, agno);
488 if (!pag->pagi_init) {
489 if (xfs_ialloc_read_agi(mp, tp, agno, &agbp)) {
490 agbp = NULL;
491 goto nextag;
492 }
493 } else
494 agbp = NULL;
495
496 if (!pag->pagi_inodeok) {
497 xfs_ialloc_next_ag(mp);
498 goto unlock_nextag;
499 }
500
501 /*
502 * Is there enough free space for the file plus a block
503 * of inodes (if we need to allocate some)?
504 */
505 ineed = pag->pagi_freecount ? 0 : XFS_IALLOC_BLOCKS(mp);
506 if (ineed && !pag->pagf_init) {
507 if (agbp == NULL &&
508 xfs_ialloc_read_agi(mp, tp, agno, &agbp)) {
509 agbp = NULL;
510 goto nextag;
511 }
512 (void)xfs_alloc_pagf_init(mp, tp, agno, flags);
513 }
514 if (!ineed || pag->pagf_init) {
515 if (ineed && !(longest = pag->pagf_longest))
516 longest = pag->pagf_flcount > 0;
517 if (!ineed ||
518 (pag->pagf_freeblks >= needspace + ineed &&
519 longest >= ineed &&
520 okalloc)) {
521 if (agbp == NULL &&
522 xfs_ialloc_read_agi(mp, tp, agno, &agbp)) {
523 agbp = NULL;
524 goto nextag;
525 }
526 xfs_perag_put(pag);
527 return agbp;
528 }
529 }
530 unlock_nextag:
531 if (agbp)
532 xfs_trans_brelse(tp, agbp);
533 nextag:
534 xfs_perag_put(pag);
535 /*
536 * No point in iterating over the rest, if we're shutting
537 * down.
538 */
539 if (XFS_FORCED_SHUTDOWN(mp))
540 return NULL;
541 agno++;
542 if (agno >= agcount)
543 agno = 0;
544 if (agno == pagno) {
545 if (flags == 0)
546 return NULL;
547 flags = 0;
548 }
549 }
550 }
551
552 /*
553 * Try to retrieve the next record to the left/right from the current one.
554 */
555 STATIC int
556 xfs_ialloc_next_rec(
557 struct xfs_btree_cur *cur,
558 xfs_inobt_rec_incore_t *rec,
559 int *done,
560 int left)
561 {
562 int error;
563 int i;
564
565 if (left)
566 error = xfs_btree_decrement(cur, 0, &i);
567 else
568 error = xfs_btree_increment(cur, 0, &i);
569
570 if (error)
571 return error;
572 *done = !i;
573 if (i) {
574 error = xfs_inobt_get_rec(cur, rec, &i);
575 if (error)
576 return error;
577 XFS_WANT_CORRUPTED_RETURN(i == 1);
578 }
579
580 return 0;
581 }
582
583 STATIC int
584 xfs_ialloc_get_rec(
585 struct xfs_btree_cur *cur,
586 xfs_agino_t agino,
587 xfs_inobt_rec_incore_t *rec,
588 int *done,
589 int left)
590 {
591 int error;
592 int i;
593
594 error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_EQ, &i);
595 if (error)
596 return error;
597 *done = !i;
598 if (i) {
599 error = xfs_inobt_get_rec(cur, rec, &i);
600 if (error)
601 return error;
602 XFS_WANT_CORRUPTED_RETURN(i == 1);
603 }
604
605 return 0;
606 }
607
608 /*
609 * Visible inode allocation functions.
610 */
611
612 /*
613 * Allocate an inode on disk.
614 * Mode is used to tell whether the new inode will need space, and whether
615 * it is a directory.
616 *
617 * The arguments IO_agbp and alloc_done are defined to work within
618 * the constraint of one allocation per transaction.
619 * xfs_dialloc() is designed to be called twice if it has to do an
620 * allocation to make more free inodes. On the first call,
621 * IO_agbp should be set to NULL. If an inode is available,
622 * i.e., xfs_dialloc() did not need to do an allocation, an inode
623 * number is returned. In this case, IO_agbp would be set to the
624 * current ag_buf and alloc_done set to false.
625 * If an allocation needed to be done, xfs_dialloc would return
626 * the current ag_buf in IO_agbp and set alloc_done to true.
627 * The caller should then commit the current transaction, allocate a new
628 * transaction, and call xfs_dialloc() again, passing in the previous
629 * value of IO_agbp. IO_agbp should be held across the transactions.
630 * Since the agbp is locked across the two calls, the second call is
631 * guaranteed to have a free inode available.
632 *
633 * Once we successfully pick an inode its number is returned and the
634 * on-disk data structures are updated. The inode itself is not read
635 * in, since doing so would break ordering constraints with xfs_reclaim.
636 */
637 int
638 xfs_dialloc(
639 xfs_trans_t *tp, /* transaction pointer */
640 xfs_ino_t parent, /* parent inode (directory) */
641 mode_t mode, /* mode bits for new inode */
642 int okalloc, /* ok to allocate more space */
643 xfs_buf_t **IO_agbp, /* in/out ag header's buffer */
644 boolean_t *alloc_done, /* true if we needed to replenish
645 inode freelist */
646 xfs_ino_t *inop) /* inode number allocated */
647 {
648 xfs_agnumber_t agcount; /* number of allocation groups */
649 xfs_buf_t *agbp; /* allocation group header's buffer */
650 xfs_agnumber_t agno; /* allocation group number */
651 xfs_agi_t *agi; /* allocation group header structure */
652 xfs_btree_cur_t *cur; /* inode allocation btree cursor */
653 int error; /* error return value */
654 int i; /* result code */
655 int ialloced; /* inode allocation status */
656 int noroom = 0; /* no space for inode blk allocation */
657 xfs_ino_t ino; /* fs-relative inode to be returned */
658 /* REFERENCED */
659 int j; /* result code */
660 xfs_mount_t *mp; /* file system mount structure */
661 int offset; /* index of inode in chunk */
662 xfs_agino_t pagino; /* parent's AG relative inode # */
663 xfs_agnumber_t pagno; /* parent's AG number */
664 xfs_inobt_rec_incore_t rec; /* inode allocation record */
665 xfs_agnumber_t tagno; /* testing allocation group number */
666 xfs_btree_cur_t *tcur; /* temp cursor */
667 xfs_inobt_rec_incore_t trec; /* temp inode allocation record */
668 struct xfs_perag *pag;
669
670
671 if (*IO_agbp == NULL) {
672 /*
673 * We do not have an agbp, so select an initial allocation
674 * group for inode allocation.
675 */
676 agbp = xfs_ialloc_ag_select(tp, parent, mode, okalloc);
677 /*
678 * Couldn't find an allocation group satisfying the
679 * criteria, give up.
680 */
681 if (!agbp) {
682 *inop = NULLFSINO;
683 return 0;
684 }
685 agi = XFS_BUF_TO_AGI(agbp);
686 ASSERT(be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC);
687 } else {
688 /*
689 * Continue where we left off before. In this case, we
690 * know that the allocation group has free inodes.
691 */
692 agbp = *IO_agbp;
693 agi = XFS_BUF_TO_AGI(agbp);
694 ASSERT(be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC);
695 ASSERT(be32_to_cpu(agi->agi_freecount) > 0);
696 }
697 mp = tp->t_mountp;
698 agcount = mp->m_sb.sb_agcount;
699 agno = be32_to_cpu(agi->agi_seqno);
700 tagno = agno;
701 pagno = XFS_INO_TO_AGNO(mp, parent);
702 pagino = XFS_INO_TO_AGINO(mp, parent);
703
704 /*
705 * If we have already hit the ceiling of inode blocks then clear
706 * okalloc so we scan all available agi structures for a free
707 * inode.
708 */
709
710 if (mp->m_maxicount &&
711 mp->m_sb.sb_icount + XFS_IALLOC_INODES(mp) > mp->m_maxicount) {
712 noroom = 1;
713 okalloc = 0;
714 }
715
716 /*
717 * Loop until we find an allocation group that either has free inodes
718 * or in which we can allocate some inodes. Iterate through the
719 * allocation groups upward, wrapping at the end.
720 */
721 *alloc_done = B_FALSE;
722 while (!agi->agi_freecount) {
723 /*
724 * Don't do anything if we're not supposed to allocate
725 * any blocks, just go on to the next ag.
726 */
727 if (okalloc) {
728 /*
729 * Try to allocate some new inodes in the allocation
730 * group.
731 */
732 if ((error = xfs_ialloc_ag_alloc(tp, agbp, &ialloced))) {
733 xfs_trans_brelse(tp, agbp);
734 if (error == ENOSPC) {
735 *inop = NULLFSINO;
736 return 0;
737 } else
738 return error;
739 }
740 if (ialloced) {
741 /*
742 * We successfully allocated some inodes, return
743 * the current context to the caller so that it
744 * can commit the current transaction and call
745 * us again where we left off.
746 */
747 ASSERT(be32_to_cpu(agi->agi_freecount) > 0);
748 *alloc_done = B_TRUE;
749 *IO_agbp = agbp;
750 *inop = NULLFSINO;
751 return 0;
752 }
753 }
754 /*
755 * If it failed, give up on this ag.
756 */
757 xfs_trans_brelse(tp, agbp);
758 /*
759 * Go on to the next ag: get its ag header.
760 */
761 nextag:
762 if (++tagno == agcount)
763 tagno = 0;
764 if (tagno == agno) {
765 *inop = NULLFSINO;
766 return noroom ? ENOSPC : 0;
767 }
768 pag = xfs_perag_get(mp, tagno);
769 if (pag->pagi_inodeok == 0) {
770 xfs_perag_put(pag);
771 goto nextag;
772 }
773 error = xfs_ialloc_read_agi(mp, tp, tagno, &agbp);
774 xfs_perag_put(pag);
775 if (error)
776 goto nextag;
777 agi = XFS_BUF_TO_AGI(agbp);
778 ASSERT(be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC);
779 }
780 /*
781 * Here with an allocation group that has a free inode.
782 * Reset agno since we may have chosen a new ag in the
783 * loop above.
784 */
785 agno = tagno;
786 *IO_agbp = NULL;
787 pag = xfs_perag_get(mp, agno);
788
789 restart_pagno:
790 cur = xfs_inobt_init_cursor(mp, tp, agbp, be32_to_cpu(agi->agi_seqno));
791 /*
792 * If pagino is 0 (this is the root inode allocation) use newino.
793 * This must work because we've just allocated some.
794 */
795 if (!pagino)
796 pagino = be32_to_cpu(agi->agi_newino);
797
798 error = xfs_check_agi_freecount(cur, agi);
799 if (error)
800 goto error0;
801
802 /*
803 * If in the same AG as the parent, try to get near the parent.
804 */
805 if (pagno == agno) {
806 int doneleft; /* done, to the left */
807 int doneright; /* done, to the right */
808 int searchdistance = 10;
809
810 error = xfs_inobt_lookup(cur, pagino, XFS_LOOKUP_LE, &i);
811 if (error)
812 goto error0;
813 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
814
815 error = xfs_inobt_get_rec(cur, &rec, &j);
816 if (error)
817 goto error0;
818 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
819
820 if (rec.ir_freecount > 0) {
821 /*
822 * Found a free inode in the same chunk
823 * as the parent, done.
824 */
825 goto alloc_inode;
826 }
827
828
829 /*
830 * In the same AG as parent, but parent's chunk is full.
831 */
832
833 /* duplicate the cursor, search left & right simultaneously */
834 error = xfs_btree_dup_cursor(cur, &tcur);
835 if (error)
836 goto error0;
837
838 /*
839 * Skip to last blocks looked up if same parent inode.
840 */
841 if (pagino != NULLAGINO &&
842 pag->pagl_pagino == pagino &&
843 pag->pagl_leftrec != NULLAGINO &&
844 pag->pagl_rightrec != NULLAGINO) {
845 error = xfs_ialloc_get_rec(tcur, pag->pagl_leftrec,
846 &trec, &doneleft, 1);
847 if (error)
848 goto error1;
849
850 error = xfs_ialloc_get_rec(cur, pag->pagl_rightrec,
851 &rec, &doneright, 0);
852 if (error)
853 goto error1;
854 } else {
855 /* search left with tcur, back up 1 record */
856 error = xfs_ialloc_next_rec(tcur, &trec, &doneleft, 1);
857 if (error)
858 goto error1;
859
860 /* search right with cur, go forward 1 record. */
861 error = xfs_ialloc_next_rec(cur, &rec, &doneright, 0);
862 if (error)
863 goto error1;
864 }
865
866 /*
867 * Loop until we find an inode chunk with a free inode.
868 */
869 while (!doneleft || !doneright) {
870 int useleft; /* using left inode chunk this time */
871
872 if (!--searchdistance) {
873 /*
874 * Not in range - save last search
875 * location and allocate a new inode
876 */
877 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
878 pag->pagl_leftrec = trec.ir_startino;
879 pag->pagl_rightrec = rec.ir_startino;
880 pag->pagl_pagino = pagino;
881 goto newino;
882 }
883
884 /* figure out the closer block if both are valid. */
885 if (!doneleft && !doneright) {
886 useleft = pagino -
887 (trec.ir_startino + XFS_INODES_PER_CHUNK - 1) <
888 rec.ir_startino - pagino;
889 } else {
890 useleft = !doneleft;
891 }
892
893 /* free inodes to the left? */
894 if (useleft && trec.ir_freecount) {
895 rec = trec;
896 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
897 cur = tcur;
898
899 pag->pagl_leftrec = trec.ir_startino;
900 pag->pagl_rightrec = rec.ir_startino;
901 pag->pagl_pagino = pagino;
902 goto alloc_inode;
903 }
904
905 /* free inodes to the right? */
906 if (!useleft && rec.ir_freecount) {
907 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
908
909 pag->pagl_leftrec = trec.ir_startino;
910 pag->pagl_rightrec = rec.ir_startino;
911 pag->pagl_pagino = pagino;
912 goto alloc_inode;
913 }
914
915 /* get next record to check */
916 if (useleft) {
917 error = xfs_ialloc_next_rec(tcur, &trec,
918 &doneleft, 1);
919 } else {
920 error = xfs_ialloc_next_rec(cur, &rec,
921 &doneright, 0);
922 }
923 if (error)
924 goto error1;
925 }
926
927 /*
928 * We've reached the end of the btree. because
929 * we are only searching a small chunk of the
930 * btree each search, there is obviously free
931 * inodes closer to the parent inode than we
932 * are now. restart the search again.
933 */
934 pag->pagl_pagino = NULLAGINO;
935 pag->pagl_leftrec = NULLAGINO;
936 pag->pagl_rightrec = NULLAGINO;
937 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
938 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
939 goto restart_pagno;
940 }
941
942 /*
943 * In a different AG from the parent.
944 * See if the most recently allocated block has any free.
945 */
946 newino:
947 if (be32_to_cpu(agi->agi_newino) != NULLAGINO) {
948 error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
949 XFS_LOOKUP_EQ, &i);
950 if (error)
951 goto error0;
952
953 if (i == 1) {
954 error = xfs_inobt_get_rec(cur, &rec, &j);
955 if (error)
956 goto error0;
957
958 if (j == 1 && rec.ir_freecount > 0) {
959 /*
960 * The last chunk allocated in the group
961 * still has a free inode.
962 */
963 goto alloc_inode;
964 }
965 }
966 }
967
968 /*
969 * None left in the last group, search the whole AG
970 */
971 error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
972 if (error)
973 goto error0;
974 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
975
976 for (;;) {
977 error = xfs_inobt_get_rec(cur, &rec, &i);
978 if (error)
979 goto error0;
980 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
981 if (rec.ir_freecount > 0)
982 break;
983 error = xfs_btree_increment(cur, 0, &i);
984 if (error)
985 goto error0;
986 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
987 }
988
989 alloc_inode:
990 offset = xfs_ialloc_find_free(&rec.ir_free);
991 ASSERT(offset >= 0);
992 ASSERT(offset < XFS_INODES_PER_CHUNK);
993 ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
994 XFS_INODES_PER_CHUNK) == 0);
995 ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino + offset);
996 rec.ir_free &= ~XFS_INOBT_MASK(offset);
997 rec.ir_freecount--;
998 error = xfs_inobt_update(cur, &rec);
999 if (error)
1000 goto error0;
1001 be32_add_cpu(&agi->agi_freecount, -1);
1002 xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1003 pag->pagi_freecount--;
1004
1005 error = xfs_check_agi_freecount(cur, agi);
1006 if (error)
1007 goto error0;
1008
1009 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1010 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
1011 xfs_perag_put(pag);
1012 *inop = ino;
1013 return 0;
1014 error1:
1015 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
1016 error0:
1017 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1018 xfs_perag_put(pag);
1019 return error;
1020 }
1021
1022 /*
1023 * Free disk inode. Carefully avoids touching the incore inode, all
1024 * manipulations incore are the caller's responsibility.
1025 * The on-disk inode is not changed by this operation, only the
1026 * btree (free inode mask) is changed.
1027 */
1028 int
1029 xfs_difree(
1030 xfs_trans_t *tp, /* transaction pointer */
1031 xfs_ino_t inode, /* inode to be freed */
1032 xfs_bmap_free_t *flist, /* extents to free */
1033 int *delete, /* set if inode cluster was deleted */
1034 xfs_ino_t *first_ino) /* first inode in deleted cluster */
1035 {
1036 /* REFERENCED */
1037 xfs_agblock_t agbno; /* block number containing inode */
1038 xfs_buf_t *agbp; /* buffer containing allocation group header */
1039 xfs_agino_t agino; /* inode number relative to allocation group */
1040 xfs_agnumber_t agno; /* allocation group number */
1041 xfs_agi_t *agi; /* allocation group header */
1042 xfs_btree_cur_t *cur; /* inode btree cursor */
1043 int error; /* error return value */
1044 int i; /* result code */
1045 int ilen; /* inodes in an inode cluster */
1046 xfs_mount_t *mp; /* mount structure for filesystem */
1047 int off; /* offset of inode in inode chunk */
1048 xfs_inobt_rec_incore_t rec; /* btree record */
1049 struct xfs_perag *pag;
1050
1051 mp = tp->t_mountp;
1052
1053 /*
1054 * Break up inode number into its components.
1055 */
1056 agno = XFS_INO_TO_AGNO(mp, inode);
1057 if (agno >= mp->m_sb.sb_agcount) {
1058 xfs_warn(mp, "%s: agno >= mp->m_sb.sb_agcount (%d >= %d).",
1059 __func__, agno, mp->m_sb.sb_agcount);
1060 ASSERT(0);
1061 return XFS_ERROR(EINVAL);
1062 }
1063 agino = XFS_INO_TO_AGINO(mp, inode);
1064 if (inode != XFS_AGINO_TO_INO(mp, agno, agino)) {
1065 xfs_warn(mp, "%s: inode != XFS_AGINO_TO_INO() (%llu != %llu).",
1066 __func__, (unsigned long long)inode,
1067 (unsigned long long)XFS_AGINO_TO_INO(mp, agno, agino));
1068 ASSERT(0);
1069 return XFS_ERROR(EINVAL);
1070 }
1071 agbno = XFS_AGINO_TO_AGBNO(mp, agino);
1072 if (agbno >= mp->m_sb.sb_agblocks) {
1073 xfs_warn(mp, "%s: agbno >= mp->m_sb.sb_agblocks (%d >= %d).",
1074 __func__, agbno, mp->m_sb.sb_agblocks);
1075 ASSERT(0);
1076 return XFS_ERROR(EINVAL);
1077 }
1078 /*
1079 * Get the allocation group header.
1080 */
1081 error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
1082 if (error) {
1083 xfs_warn(mp, "%s: xfs_ialloc_read_agi() returned error %d.",
1084 __func__, error);
1085 return error;
1086 }
1087 agi = XFS_BUF_TO_AGI(agbp);
1088 ASSERT(be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC);
1089 ASSERT(agbno < be32_to_cpu(agi->agi_length));
1090 /*
1091 * Initialize the cursor.
1092 */
1093 cur = xfs_inobt_init_cursor(mp, tp, agbp, agno);
1094
1095 error = xfs_check_agi_freecount(cur, agi);
1096 if (error)
1097 goto error0;
1098
1099 /*
1100 * Look for the entry describing this inode.
1101 */
1102 if ((error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i))) {
1103 xfs_warn(mp, "%s: xfs_inobt_lookup() returned error %d.",
1104 __func__, error);
1105 goto error0;
1106 }
1107 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1108 error = xfs_inobt_get_rec(cur, &rec, &i);
1109 if (error) {
1110 xfs_warn(mp, "%s: xfs_inobt_get_rec() returned error %d.",
1111 __func__, error);
1112 goto error0;
1113 }
1114 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1115 /*
1116 * Get the offset in the inode chunk.
1117 */
1118 off = agino - rec.ir_startino;
1119 ASSERT(off >= 0 && off < XFS_INODES_PER_CHUNK);
1120 ASSERT(!(rec.ir_free & XFS_INOBT_MASK(off)));
1121 /*
1122 * Mark the inode free & increment the count.
1123 */
1124 rec.ir_free |= XFS_INOBT_MASK(off);
1125 rec.ir_freecount++;
1126
1127 /*
1128 * When an inode cluster is free, it becomes eligible for removal
1129 */
1130 if (!(mp->m_flags & XFS_MOUNT_IKEEP) &&
1131 (rec.ir_freecount == XFS_IALLOC_INODES(mp))) {
1132
1133 *delete = 1;
1134 *first_ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino);
1135
1136 /*
1137 * Remove the inode cluster from the AGI B+Tree, adjust the
1138 * AGI and Superblock inode counts, and mark the disk space
1139 * to be freed when the transaction is committed.
1140 */
1141 ilen = XFS_IALLOC_INODES(mp);
1142 be32_add_cpu(&agi->agi_count, -ilen);
1143 be32_add_cpu(&agi->agi_freecount, -(ilen - 1));
1144 xfs_ialloc_log_agi(tp, agbp, XFS_AGI_COUNT | XFS_AGI_FREECOUNT);
1145 pag = xfs_perag_get(mp, agno);
1146 pag->pagi_freecount -= ilen - 1;
1147 xfs_perag_put(pag);
1148 xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, -ilen);
1149 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -(ilen - 1));
1150
1151 if ((error = xfs_btree_delete(cur, &i))) {
1152 xfs_warn(mp, "%s: xfs_btree_delete returned error %d.",
1153 __func__, error);
1154 goto error0;
1155 }
1156
1157 xfs_bmap_add_free(XFS_AGB_TO_FSB(mp,
1158 agno, XFS_INO_TO_AGBNO(mp,rec.ir_startino)),
1159 XFS_IALLOC_BLOCKS(mp), flist, mp);
1160 } else {
1161 *delete = 0;
1162
1163 error = xfs_inobt_update(cur, &rec);
1164 if (error) {
1165 xfs_warn(mp, "%s: xfs_inobt_update returned error %d.",
1166 __func__, error);
1167 goto error0;
1168 }
1169
1170 /*
1171 * Change the inode free counts and log the ag/sb changes.
1172 */
1173 be32_add_cpu(&agi->agi_freecount, 1);
1174 xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1175 pag = xfs_perag_get(mp, agno);
1176 pag->pagi_freecount++;
1177 xfs_perag_put(pag);
1178 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, 1);
1179 }
1180
1181 error = xfs_check_agi_freecount(cur, agi);
1182 if (error)
1183 goto error0;
1184
1185 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1186 return 0;
1187
1188 error0:
1189 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1190 return error;
1191 }
1192
1193 STATIC int
1194 xfs_imap_lookup(
1195 struct xfs_mount *mp,
1196 struct xfs_trans *tp,
1197 xfs_agnumber_t agno,
1198 xfs_agino_t agino,
1199 xfs_agblock_t agbno,
1200 xfs_agblock_t *chunk_agbno,
1201 xfs_agblock_t *offset_agbno,
1202 int flags)
1203 {
1204 struct xfs_inobt_rec_incore rec;
1205 struct xfs_btree_cur *cur;
1206 struct xfs_buf *agbp;
1207 int error;
1208 int i;
1209
1210 error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
1211 if (error) {
1212 xfs_alert(mp,
1213 "%s: xfs_ialloc_read_agi() returned error %d, agno %d",
1214 __func__, error, agno);
1215 return error;
1216 }
1217
1218 /*
1219 * Lookup the inode record for the given agino. If the record cannot be
1220 * found, then it's an invalid inode number and we should abort. Once
1221 * we have a record, we need to ensure it contains the inode number
1222 * we are looking up.
1223 */
1224 cur = xfs_inobt_init_cursor(mp, tp, agbp, agno);
1225 error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i);
1226 if (!error) {
1227 if (i)
1228 error = xfs_inobt_get_rec(cur, &rec, &i);
1229 if (!error && i == 0)
1230 error = EINVAL;
1231 }
1232
1233 xfs_trans_brelse(tp, agbp);
1234 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1235 if (error)
1236 return error;
1237
1238 /* check that the returned record contains the required inode */
1239 if (rec.ir_startino > agino ||
1240 rec.ir_startino + XFS_IALLOC_INODES(mp) <= agino)
1241 return EINVAL;
1242
1243 /* for untrusted inodes check it is allocated first */
1244 if ((flags & XFS_IGET_UNTRUSTED) &&
1245 (rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino)))
1246 return EINVAL;
1247
1248 *chunk_agbno = XFS_AGINO_TO_AGBNO(mp, rec.ir_startino);
1249 *offset_agbno = agbno - *chunk_agbno;
1250 return 0;
1251 }
1252
1253 /*
1254 * Return the location of the inode in imap, for mapping it into a buffer.
1255 */
1256 int
1257 xfs_imap(
1258 xfs_mount_t *mp, /* file system mount structure */
1259 xfs_trans_t *tp, /* transaction pointer */
1260 xfs_ino_t ino, /* inode to locate */
1261 struct xfs_imap *imap, /* location map structure */
1262 uint flags) /* flags for inode btree lookup */
1263 {
1264 xfs_agblock_t agbno; /* block number of inode in the alloc group */
1265 xfs_agino_t agino; /* inode number within alloc group */
1266 xfs_agnumber_t agno; /* allocation group number */
1267 int blks_per_cluster; /* num blocks per inode cluster */
1268 xfs_agblock_t chunk_agbno; /* first block in inode chunk */
1269 xfs_agblock_t cluster_agbno; /* first block in inode cluster */
1270 int error; /* error code */
1271 int offset; /* index of inode in its buffer */
1272 int offset_agbno; /* blks from chunk start to inode */
1273
1274 ASSERT(ino != NULLFSINO);
1275
1276 /*
1277 * Split up the inode number into its parts.
1278 */
1279 agno = XFS_INO_TO_AGNO(mp, ino);
1280 agino = XFS_INO_TO_AGINO(mp, ino);
1281 agbno = XFS_AGINO_TO_AGBNO(mp, agino);
1282 if (agno >= mp->m_sb.sb_agcount || agbno >= mp->m_sb.sb_agblocks ||
1283 ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
1284 #ifdef DEBUG
1285 /*
1286 * Don't output diagnostic information for untrusted inodes
1287 * as they can be invalid without implying corruption.
1288 */
1289 if (flags & XFS_IGET_UNTRUSTED)
1290 return XFS_ERROR(EINVAL);
1291 if (agno >= mp->m_sb.sb_agcount) {
1292 xfs_alert(mp,
1293 "%s: agno (%d) >= mp->m_sb.sb_agcount (%d)",
1294 __func__, agno, mp->m_sb.sb_agcount);
1295 }
1296 if (agbno >= mp->m_sb.sb_agblocks) {
1297 xfs_alert(mp,
1298 "%s: agbno (0x%llx) >= mp->m_sb.sb_agblocks (0x%lx)",
1299 __func__, (unsigned long long)agbno,
1300 (unsigned long)mp->m_sb.sb_agblocks);
1301 }
1302 if (ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
1303 xfs_alert(mp,
1304 "%s: ino (0x%llx) != XFS_AGINO_TO_INO() (0x%llx)",
1305 __func__, ino,
1306 XFS_AGINO_TO_INO(mp, agno, agino));
1307 }
1308 xfs_stack_trace();
1309 #endif /* DEBUG */
1310 return XFS_ERROR(EINVAL);
1311 }
1312
1313 blks_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_blocklog;
1314
1315 /*
1316 * For bulkstat and handle lookups, we have an untrusted inode number
1317 * that we have to verify is valid. We cannot do this just by reading
1318 * the inode buffer as it may have been unlinked and removed leaving
1319 * inodes in stale state on disk. Hence we have to do a btree lookup
1320 * in all cases where an untrusted inode number is passed.
1321 */
1322 if (flags & XFS_IGET_UNTRUSTED) {
1323 error = xfs_imap_lookup(mp, tp, agno, agino, agbno,
1324 &chunk_agbno, &offset_agbno, flags);
1325 if (error)
1326 return error;
1327 goto out_map;
1328 }
1329
1330 /*
1331 * If the inode cluster size is the same as the blocksize or
1332 * smaller we get to the buffer by simple arithmetics.
1333 */
1334 if (XFS_INODE_CLUSTER_SIZE(mp) <= mp->m_sb.sb_blocksize) {
1335 offset = XFS_INO_TO_OFFSET(mp, ino);
1336 ASSERT(offset < mp->m_sb.sb_inopblock);
1337
1338 imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, agbno);
1339 imap->im_len = XFS_FSB_TO_BB(mp, 1);
1340 imap->im_boffset = (ushort)(offset << mp->m_sb.sb_inodelog);
1341 return 0;
1342 }
1343
1344 /*
1345 * If the inode chunks are aligned then use simple maths to
1346 * find the location. Otherwise we have to do a btree
1347 * lookup to find the location.
1348 */
1349 if (mp->m_inoalign_mask) {
1350 offset_agbno = agbno & mp->m_inoalign_mask;
1351 chunk_agbno = agbno - offset_agbno;
1352 } else {
1353 error = xfs_imap_lookup(mp, tp, agno, agino, agbno,
1354 &chunk_agbno, &offset_agbno, flags);
1355 if (error)
1356 return error;
1357 }
1358
1359 out_map:
1360 ASSERT(agbno >= chunk_agbno);
1361 cluster_agbno = chunk_agbno +
1362 ((offset_agbno / blks_per_cluster) * blks_per_cluster);
1363 offset = ((agbno - cluster_agbno) * mp->m_sb.sb_inopblock) +
1364 XFS_INO_TO_OFFSET(mp, ino);
1365
1366 imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, cluster_agbno);
1367 imap->im_len = XFS_FSB_TO_BB(mp, blks_per_cluster);
1368 imap->im_boffset = (ushort)(offset << mp->m_sb.sb_inodelog);
1369
1370 /*
1371 * If the inode number maps to a block outside the bounds
1372 * of the file system then return NULL rather than calling
1373 * read_buf and panicing when we get an error from the
1374 * driver.
1375 */
1376 if ((imap->im_blkno + imap->im_len) >
1377 XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
1378 xfs_alert(mp,
1379 "%s: (im_blkno (0x%llx) + im_len (0x%llx)) > sb_dblocks (0x%llx)",
1380 __func__, (unsigned long long) imap->im_blkno,
1381 (unsigned long long) imap->im_len,
1382 XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks));
1383 return XFS_ERROR(EINVAL);
1384 }
1385 return 0;
1386 }
1387
1388 /*
1389 * Compute and fill in value of m_in_maxlevels.
1390 */
1391 void
1392 xfs_ialloc_compute_maxlevels(
1393 xfs_mount_t *mp) /* file system mount structure */
1394 {
1395 int level;
1396 uint maxblocks;
1397 uint maxleafents;
1398 int minleafrecs;
1399 int minnoderecs;
1400
1401 maxleafents = (1LL << XFS_INO_AGINO_BITS(mp)) >>
1402 XFS_INODES_PER_CHUNK_LOG;
1403 minleafrecs = mp->m_alloc_mnr[0];
1404 minnoderecs = mp->m_alloc_mnr[1];
1405 maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs;
1406 for (level = 1; maxblocks > 1; level++)
1407 maxblocks = (maxblocks + minnoderecs - 1) / minnoderecs;
1408 mp->m_in_maxlevels = level;
1409 }
1410
1411 /*
1412 * Log specified fields for the ag hdr (inode section)
1413 */
1414 void
1415 xfs_ialloc_log_agi(
1416 xfs_trans_t *tp, /* transaction pointer */
1417 xfs_buf_t *bp, /* allocation group header buffer */
1418 int fields) /* bitmask of fields to log */
1419 {
1420 int first; /* first byte number */
1421 int last; /* last byte number */
1422 static const short offsets[] = { /* field starting offsets */
1423 /* keep in sync with bit definitions */
1424 offsetof(xfs_agi_t, agi_magicnum),
1425 offsetof(xfs_agi_t, agi_versionnum),
1426 offsetof(xfs_agi_t, agi_seqno),
1427 offsetof(xfs_agi_t, agi_length),
1428 offsetof(xfs_agi_t, agi_count),
1429 offsetof(xfs_agi_t, agi_root),
1430 offsetof(xfs_agi_t, agi_level),
1431 offsetof(xfs_agi_t, agi_freecount),
1432 offsetof(xfs_agi_t, agi_newino),
1433 offsetof(xfs_agi_t, agi_dirino),
1434 offsetof(xfs_agi_t, agi_unlinked),
1435 sizeof(xfs_agi_t)
1436 };
1437 #ifdef DEBUG
1438 xfs_agi_t *agi; /* allocation group header */
1439
1440 agi = XFS_BUF_TO_AGI(bp);
1441 ASSERT(be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC);
1442 #endif
1443 /*
1444 * Compute byte offsets for the first and last fields.
1445 */
1446 xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS, &first, &last);
1447 /*
1448 * Log the allocation group inode header buffer.
1449 */
1450 xfs_trans_log_buf(tp, bp, first, last);
1451 }
1452
1453 #ifdef DEBUG
1454 STATIC void
1455 xfs_check_agi_unlinked(
1456 struct xfs_agi *agi)
1457 {
1458 int i;
1459
1460 for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++)
1461 ASSERT(agi->agi_unlinked[i]);
1462 }
1463 #else
1464 #define xfs_check_agi_unlinked(agi)
1465 #endif
1466
1467 /*
1468 * Read in the allocation group header (inode allocation section)
1469 */
1470 int
1471 xfs_read_agi(
1472 struct xfs_mount *mp, /* file system mount structure */
1473 struct xfs_trans *tp, /* transaction pointer */
1474 xfs_agnumber_t agno, /* allocation group number */
1475 struct xfs_buf **bpp) /* allocation group hdr buf */
1476 {
1477 struct xfs_agi *agi; /* allocation group header */
1478 int agi_ok; /* agi is consistent */
1479 int error;
1480
1481 ASSERT(agno != NULLAGNUMBER);
1482
1483 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
1484 XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
1485 XFS_FSS_TO_BB(mp, 1), 0, bpp);
1486 if (error)
1487 return error;
1488
1489 ASSERT(*bpp && !XFS_BUF_GETERROR(*bpp));
1490 agi = XFS_BUF_TO_AGI(*bpp);
1491
1492 /*
1493 * Validate the magic number of the agi block.
1494 */
1495 agi_ok = be32_to_cpu(agi->agi_magicnum) == XFS_AGI_MAGIC &&
1496 XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)) &&
1497 be32_to_cpu(agi->agi_seqno) == agno;
1498 if (unlikely(XFS_TEST_ERROR(!agi_ok, mp, XFS_ERRTAG_IALLOC_READ_AGI,
1499 XFS_RANDOM_IALLOC_READ_AGI))) {
1500 XFS_CORRUPTION_ERROR("xfs_read_agi", XFS_ERRLEVEL_LOW,
1501 mp, agi);
1502 xfs_trans_brelse(tp, *bpp);
1503 return XFS_ERROR(EFSCORRUPTED);
1504 }
1505
1506 XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_AGI, XFS_AGI_REF);
1507
1508 xfs_check_agi_unlinked(agi);
1509 return 0;
1510 }
1511
1512 int
1513 xfs_ialloc_read_agi(
1514 struct xfs_mount *mp, /* file system mount structure */
1515 struct xfs_trans *tp, /* transaction pointer */
1516 xfs_agnumber_t agno, /* allocation group number */
1517 struct xfs_buf **bpp) /* allocation group hdr buf */
1518 {
1519 struct xfs_agi *agi; /* allocation group header */
1520 struct xfs_perag *pag; /* per allocation group data */
1521 int error;
1522
1523 error = xfs_read_agi(mp, tp, agno, bpp);
1524 if (error)
1525 return error;
1526
1527 agi = XFS_BUF_TO_AGI(*bpp);
1528 pag = xfs_perag_get(mp, agno);
1529 if (!pag->pagi_init) {
1530 pag->pagi_freecount = be32_to_cpu(agi->agi_freecount);
1531 pag->pagi_count = be32_to_cpu(agi->agi_count);
1532 pag->pagi_init = 1;
1533 }
1534
1535 /*
1536 * It's possible for these to be out of sync if
1537 * we are in the middle of a forced shutdown.
1538 */
1539 ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) ||
1540 XFS_FORCED_SHUTDOWN(mp));
1541 xfs_perag_put(pag);
1542 return 0;
1543 }
1544
1545 /*
1546 * Read in the agi to initialise the per-ag data in the mount structure
1547 */
1548 int
1549 xfs_ialloc_pagi_init(
1550 xfs_mount_t *mp, /* file system mount structure */
1551 xfs_trans_t *tp, /* transaction pointer */
1552 xfs_agnumber_t agno) /* allocation group number */
1553 {
1554 xfs_buf_t *bp = NULL;
1555 int error;
1556
1557 error = xfs_ialloc_read_agi(mp, tp, agno, &bp);
1558 if (error)
1559 return error;
1560 if (bp)
1561 xfs_trans_brelse(tp, bp);
1562 return 0;
1563 }
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