2 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
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.
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.
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
20 #include "xfs_types.h"
24 #include "xfs_trans.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"
39 #include "xfs_cksum.h"
40 #include "xfs_buf_item.h"
41 #include "xfs_icreate_item.h"
45 * Allocation group level functions.
48 xfs_ialloc_cluster_alignment(
49 xfs_alloc_arg_t *args)
51 if (xfs_sb_version_hasalign(&args->mp->m_sb) &&
52 args->mp->m_sb.sb_inoalignmt >=
53 XFS_B_TO_FSBT(args->mp, XFS_INODE_CLUSTER_SIZE(args->mp)))
54 return args->mp->m_sb.sb_inoalignmt;
59 * Lookup a record by ino in the btree given by cur.
63 struct xfs_btree_cur *cur, /* btree cursor */
64 xfs_agino_t ino, /* starting inode of chunk */
65 xfs_lookup_t dir, /* <=, >=, == */
66 int *stat) /* success/failure */
68 cur->bc_rec.i.ir_startino = ino;
69 cur->bc_rec.i.ir_freecount = 0;
70 cur->bc_rec.i.ir_free = 0;
71 return xfs_btree_lookup(cur, dir, stat);
75 * Update the record referred to by cur to the value given.
76 * This either works (return 0) or gets an EFSCORRUPTED error.
78 STATIC int /* error */
80 struct xfs_btree_cur *cur, /* btree cursor */
81 xfs_inobt_rec_incore_t *irec) /* btree record */
83 union xfs_btree_rec rec;
85 rec.inobt.ir_startino = cpu_to_be32(irec->ir_startino);
86 rec.inobt.ir_freecount = cpu_to_be32(irec->ir_freecount);
87 rec.inobt.ir_free = cpu_to_be64(irec->ir_free);
88 return xfs_btree_update(cur, &rec);
92 * Get the data from the pointed-to record.
96 struct xfs_btree_cur *cur, /* btree cursor */
97 xfs_inobt_rec_incore_t *irec, /* btree record */
98 int *stat) /* output: success/failure */
100 union xfs_btree_rec *rec;
103 error = xfs_btree_get_rec(cur, &rec, stat);
104 if (!error && *stat == 1) {
105 irec->ir_startino = be32_to_cpu(rec->inobt.ir_startino);
106 irec->ir_freecount = be32_to_cpu(rec->inobt.ir_freecount);
107 irec->ir_free = be64_to_cpu(rec->inobt.ir_free);
113 * Verify that the number of free inodes in the AGI is correct.
117 xfs_check_agi_freecount(
118 struct xfs_btree_cur *cur,
121 if (cur->bc_nlevels == 1) {
122 xfs_inobt_rec_incore_t rec;
127 error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
132 error = xfs_inobt_get_rec(cur, &rec, &i);
137 freecount += rec.ir_freecount;
138 error = xfs_btree_increment(cur, 0, &i);
144 if (!XFS_FORCED_SHUTDOWN(cur->bc_mp))
145 ASSERT(freecount == be32_to_cpu(agi->agi_freecount));
150 #define xfs_check_agi_freecount(cur, agi) 0
154 * Initialise a new set of inodes. When called without a transaction context
155 * (e.g. from recovery) we initiate a delayed write of the inode buffers rather
156 * than logging them (which in a transaction context puts them into the AIL
157 * for writeback rather than the xfsbufd queue).
160 xfs_ialloc_inode_init(
161 struct xfs_mount *mp,
162 struct xfs_trans *tp,
163 struct list_head *buffer_list,
166 xfs_agblock_t length,
169 struct xfs_buf *fbuf;
170 struct xfs_dinode *free;
171 int blks_per_cluster, nbufs, ninodes;
178 * Loop over the new block(s), filling in the inodes.
179 * For small block sizes, manipulate the inodes in buffers
180 * which are multiples of the blocks size.
182 if (mp->m_sb.sb_blocksize >= XFS_INODE_CLUSTER_SIZE(mp)) {
183 blks_per_cluster = 1;
185 ninodes = mp->m_sb.sb_inopblock;
187 blks_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) /
188 mp->m_sb.sb_blocksize;
189 nbufs = length / blks_per_cluster;
190 ninodes = blks_per_cluster * mp->m_sb.sb_inopblock;
194 * Figure out what version number to use in the inodes we create. If
195 * the superblock version has caught up to the one that supports the new
196 * inode format, then use the new inode version. Otherwise use the old
197 * version so that old kernels will continue to be able to use the file
200 * For v3 inodes, we also need to write the inode number into the inode,
201 * so calculate the first inode number of the chunk here as
202 * XFS_OFFBNO_TO_AGINO() only works within a filesystem block, not
203 * across multiple filesystem blocks (such as a cluster) and so cannot
204 * be used in the cluster buffer loop below.
206 * Further, because we are writing the inode directly into the buffer
207 * and calculating a CRC on the entire inode, we have ot log the entire
208 * inode so that the entire range the CRC covers is present in the log.
209 * That means for v3 inode we log the entire buffer rather than just the
212 if (xfs_sb_version_hascrc(&mp->m_sb)) {
214 ino = XFS_AGINO_TO_INO(mp, agno,
215 XFS_OFFBNO_TO_AGINO(mp, agbno, 0));
218 * log the initialisation that is about to take place as an
219 * logical operation. This means the transaction does not
220 * need to log the physical changes to the inode buffers as log
221 * recovery will know what initialisation is actually needed.
222 * Hence we only need to log the buffers as "ordered" buffers so
223 * they track in the AIL as if they were physically logged.
226 xfs_icreate_log(tp, agno, agbno, XFS_IALLOC_INODES(mp),
227 mp->m_sb.sb_inodesize, length, gen);
228 } else if (xfs_sb_version_hasnlink(&mp->m_sb))
233 for (j = 0; j < nbufs; j++) {
237 d = XFS_AGB_TO_DADDR(mp, agno, agbno + (j * blks_per_cluster));
238 fbuf = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
239 mp->m_bsize * blks_per_cluster,
244 /* Initialize the inode buffers and log them appropriately. */
245 fbuf->b_ops = &xfs_inode_buf_ops;
246 xfs_buf_zero(fbuf, 0, BBTOB(fbuf->b_length));
247 for (i = 0; i < ninodes; i++) {
248 int ioffset = i << mp->m_sb.sb_inodelog;
249 uint isize = xfs_dinode_size(version);
251 free = xfs_make_iptr(mp, fbuf, i);
252 free->di_magic = cpu_to_be16(XFS_DINODE_MAGIC);
253 free->di_version = version;
254 free->di_gen = cpu_to_be32(gen);
255 free->di_next_unlinked = cpu_to_be32(NULLAGINO);
258 free->di_ino = cpu_to_be64(ino);
260 uuid_copy(&free->di_uuid, &mp->m_sb.sb_uuid);
261 xfs_dinode_calc_crc(mp, free);
263 /* just log the inode core */
264 xfs_trans_log_buf(tp, fbuf, ioffset,
265 ioffset + isize - 1);
271 * Mark the buffer as an inode allocation buffer so it
272 * sticks in AIL at the point of this allocation
273 * transaction. This ensures the they are on disk before
274 * the tail of the log can be moved past this
275 * transaction (i.e. by preventing relogging from moving
276 * it forward in the log).
278 xfs_trans_inode_alloc_buf(tp, fbuf);
281 * Mark the buffer as ordered so that they are
282 * not physically logged in the transaction but
283 * still tracked in the AIL as part of the
284 * transaction and pin the log appropriately.
286 xfs_trans_ordered_buf(tp, fbuf);
287 xfs_trans_log_buf(tp, fbuf, 0,
288 BBTOB(fbuf->b_length) - 1);
291 fbuf->b_flags |= XBF_DONE;
292 xfs_buf_delwri_queue(fbuf, buffer_list);
300 * Allocate new inodes in the allocation group specified by agbp.
301 * Return 0 for success, else error code.
303 STATIC int /* error code or 0 */
305 xfs_trans_t *tp, /* transaction pointer */
306 xfs_buf_t *agbp, /* alloc group buffer */
309 xfs_agi_t *agi; /* allocation group header */
310 xfs_alloc_arg_t args; /* allocation argument structure */
311 xfs_btree_cur_t *cur; /* inode btree cursor */
315 xfs_agino_t newino; /* new first inode's number */
316 xfs_agino_t newlen; /* new number of inodes */
317 xfs_agino_t thisino; /* current inode number, for loop */
318 int isaligned = 0; /* inode allocation at stripe unit */
320 struct xfs_perag *pag;
322 memset(&args, 0, sizeof(args));
324 args.mp = tp->t_mountp;
327 * Locking will ensure that we don't have two callers in here
330 newlen = XFS_IALLOC_INODES(args.mp);
331 if (args.mp->m_maxicount &&
332 args.mp->m_sb.sb_icount + newlen > args.mp->m_maxicount)
333 return XFS_ERROR(ENOSPC);
334 args.minlen = args.maxlen = XFS_IALLOC_BLOCKS(args.mp);
336 * First try to allocate inodes contiguous with the last-allocated
337 * chunk of inodes. If the filesystem is striped, this will fill
338 * an entire stripe unit with inodes.
340 agi = XFS_BUF_TO_AGI(agbp);
341 newino = be32_to_cpu(agi->agi_newino);
342 agno = be32_to_cpu(agi->agi_seqno);
343 args.agbno = XFS_AGINO_TO_AGBNO(args.mp, newino) +
344 XFS_IALLOC_BLOCKS(args.mp);
345 if (likely(newino != NULLAGINO &&
346 (args.agbno < be32_to_cpu(agi->agi_length)))) {
347 args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
348 args.type = XFS_ALLOCTYPE_THIS_BNO;
352 * We need to take into account alignment here to ensure that
353 * we don't modify the free list if we fail to have an exact
354 * block. If we don't have an exact match, and every oher
355 * attempt allocation attempt fails, we'll end up cancelling
356 * a dirty transaction and shutting down.
358 * For an exact allocation, alignment must be 1,
359 * however we need to take cluster alignment into account when
360 * fixing up the freelist. Use the minalignslop field to
361 * indicate that extra blocks might be required for alignment,
362 * but not to use them in the actual exact allocation.
365 args.minalignslop = xfs_ialloc_cluster_alignment(&args) - 1;
367 /* Allow space for the inode btree to split. */
368 args.minleft = args.mp->m_in_maxlevels - 1;
369 if ((error = xfs_alloc_vextent(&args)))
372 args.fsbno = NULLFSBLOCK;
374 if (unlikely(args.fsbno == NULLFSBLOCK)) {
376 * Set the alignment for the allocation.
377 * If stripe alignment is turned on then align at stripe unit
379 * If the cluster size is smaller than a filesystem block
380 * then we're doing I/O for inodes in filesystem block size
381 * pieces, so don't need alignment anyway.
384 if (args.mp->m_sinoalign) {
385 ASSERT(!(args.mp->m_flags & XFS_MOUNT_NOALIGN));
386 args.alignment = args.mp->m_dalign;
389 args.alignment = xfs_ialloc_cluster_alignment(&args);
391 * Need to figure out where to allocate the inode blocks.
392 * Ideally they should be spaced out through the a.g.
393 * For now, just allocate blocks up front.
395 args.agbno = be32_to_cpu(agi->agi_root);
396 args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
398 * Allocate a fixed-size extent of inodes.
400 args.type = XFS_ALLOCTYPE_NEAR_BNO;
403 * Allow space for the inode btree to split.
405 args.minleft = args.mp->m_in_maxlevels - 1;
406 if ((error = xfs_alloc_vextent(&args)))
411 * If stripe alignment is turned on, then try again with cluster
414 if (isaligned && args.fsbno == NULLFSBLOCK) {
415 args.type = XFS_ALLOCTYPE_NEAR_BNO;
416 args.agbno = be32_to_cpu(agi->agi_root);
417 args.fsbno = XFS_AGB_TO_FSB(args.mp, agno, args.agbno);
418 args.alignment = xfs_ialloc_cluster_alignment(&args);
419 if ((error = xfs_alloc_vextent(&args)))
423 if (args.fsbno == NULLFSBLOCK) {
427 ASSERT(args.len == args.minlen);
430 * Stamp and write the inode buffers.
432 * Seed the new inode cluster with a random generation number. This
433 * prevents short-term reuse of generation numbers if a chunk is
434 * freed and then immediately reallocated. We use random numbers
435 * rather than a linear progression to prevent the next generation
436 * number from being easily guessable.
438 error = xfs_ialloc_inode_init(args.mp, tp, NULL, agno, args.agbno,
439 args.len, prandom_u32());
444 * Convert the results.
446 newino = XFS_OFFBNO_TO_AGINO(args.mp, args.agbno, 0);
447 be32_add_cpu(&agi->agi_count, newlen);
448 be32_add_cpu(&agi->agi_freecount, newlen);
449 pag = xfs_perag_get(args.mp, agno);
450 pag->pagi_freecount += newlen;
452 agi->agi_newino = cpu_to_be32(newino);
455 * Insert records describing the new inode chunk into the btree.
457 cur = xfs_inobt_init_cursor(args.mp, tp, agbp, agno);
458 for (thisino = newino;
459 thisino < newino + newlen;
460 thisino += XFS_INODES_PER_CHUNK) {
461 cur->bc_rec.i.ir_startino = thisino;
462 cur->bc_rec.i.ir_freecount = XFS_INODES_PER_CHUNK;
463 cur->bc_rec.i.ir_free = XFS_INOBT_ALL_FREE;
464 error = xfs_btree_lookup(cur, XFS_LOOKUP_EQ, &i);
466 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
470 error = xfs_btree_insert(cur, &i);
472 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
477 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
479 * Log allocation group header fields
481 xfs_ialloc_log_agi(tp, agbp,
482 XFS_AGI_COUNT | XFS_AGI_FREECOUNT | XFS_AGI_NEWINO);
484 * Modify/log superblock values for inode count and inode free count.
486 xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, (long)newlen);
487 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, (long)newlen);
492 STATIC xfs_agnumber_t
498 spin_lock(&mp->m_agirotor_lock);
499 agno = mp->m_agirotor;
500 if (++mp->m_agirotor >= mp->m_maxagi)
502 spin_unlock(&mp->m_agirotor_lock);
508 * Select an allocation group to look for a free inode in, based on the parent
509 * inode and then mode. Return the allocation group buffer.
511 STATIC xfs_agnumber_t
512 xfs_ialloc_ag_select(
513 xfs_trans_t *tp, /* transaction pointer */
514 xfs_ino_t parent, /* parent directory inode number */
515 umode_t mode, /* bits set to indicate file type */
516 int okalloc) /* ok to allocate more space */
518 xfs_agnumber_t agcount; /* number of ag's in the filesystem */
519 xfs_agnumber_t agno; /* current ag number */
520 int flags; /* alloc buffer locking flags */
521 xfs_extlen_t ineed; /* blocks needed for inode allocation */
522 xfs_extlen_t longest = 0; /* longest extent available */
523 xfs_mount_t *mp; /* mount point structure */
524 int needspace; /* file mode implies space allocated */
525 xfs_perag_t *pag; /* per allocation group data */
526 xfs_agnumber_t pagno; /* parent (starting) ag number */
530 * Files of these types need at least one block if length > 0
531 * (and they won't fit in the inode, but that's hard to figure out).
533 needspace = S_ISDIR(mode) || S_ISREG(mode) || S_ISLNK(mode);
535 agcount = mp->m_maxagi;
537 pagno = xfs_ialloc_next_ag(mp);
539 pagno = XFS_INO_TO_AGNO(mp, parent);
540 if (pagno >= agcount)
544 ASSERT(pagno < agcount);
547 * Loop through allocation groups, looking for one with a little
548 * free space in it. Note we don't look for free inodes, exactly.
549 * Instead, we include whether there is a need to allocate inodes
550 * to mean that blocks must be allocated for them,
551 * if none are currently free.
554 flags = XFS_ALLOC_FLAG_TRYLOCK;
556 pag = xfs_perag_get(mp, agno);
557 if (!pag->pagi_inodeok) {
558 xfs_ialloc_next_ag(mp);
562 if (!pag->pagi_init) {
563 error = xfs_ialloc_pagi_init(mp, tp, agno);
568 if (pag->pagi_freecount) {
576 if (!pag->pagf_init) {
577 error = xfs_alloc_pagf_init(mp, tp, agno, flags);
583 * Is there enough free space for the file plus a block of
584 * inodes? (if we need to allocate some)?
586 ineed = XFS_IALLOC_BLOCKS(mp);
587 longest = pag->pagf_longest;
589 longest = pag->pagf_flcount > 0;
591 if (pag->pagf_freeblks >= needspace + ineed &&
599 * No point in iterating over the rest, if we're shutting
602 if (XFS_FORCED_SHUTDOWN(mp))
616 * Try to retrieve the next record to the left/right from the current one.
620 struct xfs_btree_cur *cur,
621 xfs_inobt_rec_incore_t *rec,
629 error = xfs_btree_decrement(cur, 0, &i);
631 error = xfs_btree_increment(cur, 0, &i);
637 error = xfs_inobt_get_rec(cur, rec, &i);
640 XFS_WANT_CORRUPTED_RETURN(i == 1);
648 struct xfs_btree_cur *cur,
650 xfs_inobt_rec_incore_t *rec,
656 error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_EQ, &i);
661 error = xfs_inobt_get_rec(cur, rec, &i);
664 XFS_WANT_CORRUPTED_RETURN(i == 1);
673 * The caller selected an AG for us, and made sure that free inodes are
678 struct xfs_trans *tp,
679 struct xfs_buf *agbp,
683 struct xfs_mount *mp = tp->t_mountp;
684 struct xfs_agi *agi = XFS_BUF_TO_AGI(agbp);
685 xfs_agnumber_t agno = be32_to_cpu(agi->agi_seqno);
686 xfs_agnumber_t pagno = XFS_INO_TO_AGNO(mp, parent);
687 xfs_agino_t pagino = XFS_INO_TO_AGINO(mp, parent);
688 struct xfs_perag *pag;
689 struct xfs_btree_cur *cur, *tcur;
690 struct xfs_inobt_rec_incore rec, trec;
696 pag = xfs_perag_get(mp, agno);
698 ASSERT(pag->pagi_init);
699 ASSERT(pag->pagi_inodeok);
700 ASSERT(pag->pagi_freecount > 0);
703 cur = xfs_inobt_init_cursor(mp, tp, agbp, agno);
705 * If pagino is 0 (this is the root inode allocation) use newino.
706 * This must work because we've just allocated some.
709 pagino = be32_to_cpu(agi->agi_newino);
711 error = xfs_check_agi_freecount(cur, agi);
716 * If in the same AG as the parent, try to get near the parent.
719 int doneleft; /* done, to the left */
720 int doneright; /* done, to the right */
721 int searchdistance = 10;
723 error = xfs_inobt_lookup(cur, pagino, XFS_LOOKUP_LE, &i);
726 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
728 error = xfs_inobt_get_rec(cur, &rec, &j);
731 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
733 if (rec.ir_freecount > 0) {
735 * Found a free inode in the same chunk
736 * as the parent, done.
743 * In the same AG as parent, but parent's chunk is full.
746 /* duplicate the cursor, search left & right simultaneously */
747 error = xfs_btree_dup_cursor(cur, &tcur);
752 * Skip to last blocks looked up if same parent inode.
754 if (pagino != NULLAGINO &&
755 pag->pagl_pagino == pagino &&
756 pag->pagl_leftrec != NULLAGINO &&
757 pag->pagl_rightrec != NULLAGINO) {
758 error = xfs_ialloc_get_rec(tcur, pag->pagl_leftrec,
763 error = xfs_ialloc_get_rec(cur, pag->pagl_rightrec,
768 /* search left with tcur, back up 1 record */
769 error = xfs_ialloc_next_rec(tcur, &trec, &doneleft, 1);
773 /* search right with cur, go forward 1 record. */
774 error = xfs_ialloc_next_rec(cur, &rec, &doneright, 0);
780 * Loop until we find an inode chunk with a free inode.
782 while (!doneleft || !doneright) {
783 int useleft; /* using left inode chunk this time */
785 if (!--searchdistance) {
787 * Not in range - save last search
788 * location and allocate a new inode
790 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
791 pag->pagl_leftrec = trec.ir_startino;
792 pag->pagl_rightrec = rec.ir_startino;
793 pag->pagl_pagino = pagino;
797 /* figure out the closer block if both are valid. */
798 if (!doneleft && !doneright) {
800 (trec.ir_startino + XFS_INODES_PER_CHUNK - 1) <
801 rec.ir_startino - pagino;
806 /* free inodes to the left? */
807 if (useleft && trec.ir_freecount) {
809 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
812 pag->pagl_leftrec = trec.ir_startino;
813 pag->pagl_rightrec = rec.ir_startino;
814 pag->pagl_pagino = pagino;
818 /* free inodes to the right? */
819 if (!useleft && rec.ir_freecount) {
820 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
822 pag->pagl_leftrec = trec.ir_startino;
823 pag->pagl_rightrec = rec.ir_startino;
824 pag->pagl_pagino = pagino;
828 /* get next record to check */
830 error = xfs_ialloc_next_rec(tcur, &trec,
833 error = xfs_ialloc_next_rec(cur, &rec,
841 * We've reached the end of the btree. because
842 * we are only searching a small chunk of the
843 * btree each search, there is obviously free
844 * inodes closer to the parent inode than we
845 * are now. restart the search again.
847 pag->pagl_pagino = NULLAGINO;
848 pag->pagl_leftrec = NULLAGINO;
849 pag->pagl_rightrec = NULLAGINO;
850 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
851 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
856 * In a different AG from the parent.
857 * See if the most recently allocated block has any free.
860 if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
861 error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
867 error = xfs_inobt_get_rec(cur, &rec, &j);
871 if (j == 1 && rec.ir_freecount > 0) {
873 * The last chunk allocated in the group
874 * still has a free inode.
882 * None left in the last group, search the whole AG
884 error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &i);
887 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
890 error = xfs_inobt_get_rec(cur, &rec, &i);
893 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
894 if (rec.ir_freecount > 0)
896 error = xfs_btree_increment(cur, 0, &i);
899 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
903 offset = xfs_lowbit64(rec.ir_free);
905 ASSERT(offset < XFS_INODES_PER_CHUNK);
906 ASSERT((XFS_AGINO_TO_OFFSET(mp, rec.ir_startino) %
907 XFS_INODES_PER_CHUNK) == 0);
908 ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino + offset);
909 rec.ir_free &= ~XFS_INOBT_MASK(offset);
911 error = xfs_inobt_update(cur, &rec);
914 be32_add_cpu(&agi->agi_freecount, -1);
915 xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
916 pag->pagi_freecount--;
918 error = xfs_check_agi_freecount(cur, agi);
922 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
923 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -1);
928 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
930 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
936 * Allocate an inode on disk.
938 * Mode is used to tell whether the new inode will need space, and whether it
941 * This function is designed to be called twice if it has to do an allocation
942 * to make more free inodes. On the first call, *IO_agbp should be set to NULL.
943 * If an inode is available without having to performn an allocation, an inode
944 * number is returned. In this case, *IO_agbp is set to NULL. If an allocation
945 * needs to be done, xfs_dialloc returns the current AGI buffer in *IO_agbp.
946 * The caller should then commit the current transaction, allocate a
947 * new transaction, and call xfs_dialloc() again, passing in the previous value
948 * of *IO_agbp. IO_agbp should be held across the transactions. Since the AGI
949 * buffer is locked across the two calls, the second call is guaranteed to have
950 * a free inode available.
952 * Once we successfully pick an inode its number is returned and the on-disk
953 * data structures are updated. The inode itself is not read in, since doing so
954 * would break ordering constraints with xfs_reclaim.
958 struct xfs_trans *tp,
962 struct xfs_buf **IO_agbp,
965 struct xfs_mount *mp = tp->t_mountp;
966 struct xfs_buf *agbp;
971 xfs_agnumber_t start_agno;
972 struct xfs_perag *pag;
976 * If the caller passes in a pointer to the AGI buffer,
977 * continue where we left off before. In this case, we
978 * know that the allocation group has free inodes.
985 * We do not have an agbp, so select an initial allocation
986 * group for inode allocation.
988 start_agno = xfs_ialloc_ag_select(tp, parent, mode, okalloc);
989 if (start_agno == NULLAGNUMBER) {
995 * If we have already hit the ceiling of inode blocks then clear
996 * okalloc so we scan all available agi structures for a free
999 if (mp->m_maxicount &&
1000 mp->m_sb.sb_icount + XFS_IALLOC_INODES(mp) > mp->m_maxicount) {
1006 * Loop until we find an allocation group that either has free inodes
1007 * or in which we can allocate some inodes. Iterate through the
1008 * allocation groups upward, wrapping at the end.
1012 pag = xfs_perag_get(mp, agno);
1013 if (!pag->pagi_inodeok) {
1014 xfs_ialloc_next_ag(mp);
1018 if (!pag->pagi_init) {
1019 error = xfs_ialloc_pagi_init(mp, tp, agno);
1025 * Do a first racy fast path check if this AG is usable.
1027 if (!pag->pagi_freecount && !okalloc)
1031 * Then read in the AGI buffer and recheck with the AGI buffer
1034 error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
1038 if (pag->pagi_freecount) {
1044 goto nextag_relse_buffer;
1047 error = xfs_ialloc_ag_alloc(tp, agbp, &ialloced);
1049 xfs_trans_brelse(tp, agbp);
1051 if (error != ENOSPC)
1061 * We successfully allocated some inodes, return
1062 * the current context to the caller so that it
1063 * can commit the current transaction and call
1064 * us again where we left off.
1066 ASSERT(pag->pagi_freecount > 0);
1074 nextag_relse_buffer:
1075 xfs_trans_brelse(tp, agbp);
1078 if (++agno == mp->m_sb.sb_agcount)
1080 if (agno == start_agno) {
1082 return noroom ? ENOSPC : 0;
1088 return xfs_dialloc_ag(tp, agbp, parent, inop);
1091 return XFS_ERROR(error);
1095 * Free disk inode. Carefully avoids touching the incore inode, all
1096 * manipulations incore are the caller's responsibility.
1097 * The on-disk inode is not changed by this operation, only the
1098 * btree (free inode mask) is changed.
1102 xfs_trans_t *tp, /* transaction pointer */
1103 xfs_ino_t inode, /* inode to be freed */
1104 xfs_bmap_free_t *flist, /* extents to free */
1105 int *delete, /* set if inode cluster was deleted */
1106 xfs_ino_t *first_ino) /* first inode in deleted cluster */
1109 xfs_agblock_t agbno; /* block number containing inode */
1110 xfs_buf_t *agbp; /* buffer containing allocation group header */
1111 xfs_agino_t agino; /* inode number relative to allocation group */
1112 xfs_agnumber_t agno; /* allocation group number */
1113 xfs_agi_t *agi; /* allocation group header */
1114 xfs_btree_cur_t *cur; /* inode btree cursor */
1115 int error; /* error return value */
1116 int i; /* result code */
1117 int ilen; /* inodes in an inode cluster */
1118 xfs_mount_t *mp; /* mount structure for filesystem */
1119 int off; /* offset of inode in inode chunk */
1120 xfs_inobt_rec_incore_t rec; /* btree record */
1121 struct xfs_perag *pag;
1126 * Break up inode number into its components.
1128 agno = XFS_INO_TO_AGNO(mp, inode);
1129 if (agno >= mp->m_sb.sb_agcount) {
1130 xfs_warn(mp, "%s: agno >= mp->m_sb.sb_agcount (%d >= %d).",
1131 __func__, agno, mp->m_sb.sb_agcount);
1133 return XFS_ERROR(EINVAL);
1135 agino = XFS_INO_TO_AGINO(mp, inode);
1136 if (inode != XFS_AGINO_TO_INO(mp, agno, agino)) {
1137 xfs_warn(mp, "%s: inode != XFS_AGINO_TO_INO() (%llu != %llu).",
1138 __func__, (unsigned long long)inode,
1139 (unsigned long long)XFS_AGINO_TO_INO(mp, agno, agino));
1141 return XFS_ERROR(EINVAL);
1143 agbno = XFS_AGINO_TO_AGBNO(mp, agino);
1144 if (agbno >= mp->m_sb.sb_agblocks) {
1145 xfs_warn(mp, "%s: agbno >= mp->m_sb.sb_agblocks (%d >= %d).",
1146 __func__, agbno, mp->m_sb.sb_agblocks);
1148 return XFS_ERROR(EINVAL);
1151 * Get the allocation group header.
1153 error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
1155 xfs_warn(mp, "%s: xfs_ialloc_read_agi() returned error %d.",
1159 agi = XFS_BUF_TO_AGI(agbp);
1160 ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
1161 ASSERT(agbno < be32_to_cpu(agi->agi_length));
1163 * Initialize the cursor.
1165 cur = xfs_inobt_init_cursor(mp, tp, agbp, agno);
1167 error = xfs_check_agi_freecount(cur, agi);
1172 * Look for the entry describing this inode.
1174 if ((error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i))) {
1175 xfs_warn(mp, "%s: xfs_inobt_lookup() returned error %d.",
1179 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1180 error = xfs_inobt_get_rec(cur, &rec, &i);
1182 xfs_warn(mp, "%s: xfs_inobt_get_rec() returned error %d.",
1186 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
1188 * Get the offset in the inode chunk.
1190 off = agino - rec.ir_startino;
1191 ASSERT(off >= 0 && off < XFS_INODES_PER_CHUNK);
1192 ASSERT(!(rec.ir_free & XFS_INOBT_MASK(off)));
1194 * Mark the inode free & increment the count.
1196 rec.ir_free |= XFS_INOBT_MASK(off);
1200 * When an inode cluster is free, it becomes eligible for removal
1202 if (!(mp->m_flags & XFS_MOUNT_IKEEP) &&
1203 (rec.ir_freecount == XFS_IALLOC_INODES(mp))) {
1206 *first_ino = XFS_AGINO_TO_INO(mp, agno, rec.ir_startino);
1209 * Remove the inode cluster from the AGI B+Tree, adjust the
1210 * AGI and Superblock inode counts, and mark the disk space
1211 * to be freed when the transaction is committed.
1213 ilen = XFS_IALLOC_INODES(mp);
1214 be32_add_cpu(&agi->agi_count, -ilen);
1215 be32_add_cpu(&agi->agi_freecount, -(ilen - 1));
1216 xfs_ialloc_log_agi(tp, agbp, XFS_AGI_COUNT | XFS_AGI_FREECOUNT);
1217 pag = xfs_perag_get(mp, agno);
1218 pag->pagi_freecount -= ilen - 1;
1220 xfs_trans_mod_sb(tp, XFS_TRANS_SB_ICOUNT, -ilen);
1221 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, -(ilen - 1));
1223 if ((error = xfs_btree_delete(cur, &i))) {
1224 xfs_warn(mp, "%s: xfs_btree_delete returned error %d.",
1229 xfs_bmap_add_free(XFS_AGB_TO_FSB(mp,
1230 agno, XFS_INO_TO_AGBNO(mp,rec.ir_startino)),
1231 XFS_IALLOC_BLOCKS(mp), flist, mp);
1235 error = xfs_inobt_update(cur, &rec);
1237 xfs_warn(mp, "%s: xfs_inobt_update returned error %d.",
1243 * Change the inode free counts and log the ag/sb changes.
1245 be32_add_cpu(&agi->agi_freecount, 1);
1246 xfs_ialloc_log_agi(tp, agbp, XFS_AGI_FREECOUNT);
1247 pag = xfs_perag_get(mp, agno);
1248 pag->pagi_freecount++;
1250 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IFREE, 1);
1253 error = xfs_check_agi_freecount(cur, agi);
1257 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1261 xfs_btree_del_cursor(cur, XFS_BTREE_ERROR);
1267 struct xfs_mount *mp,
1268 struct xfs_trans *tp,
1269 xfs_agnumber_t agno,
1271 xfs_agblock_t agbno,
1272 xfs_agblock_t *chunk_agbno,
1273 xfs_agblock_t *offset_agbno,
1276 struct xfs_inobt_rec_incore rec;
1277 struct xfs_btree_cur *cur;
1278 struct xfs_buf *agbp;
1282 error = xfs_ialloc_read_agi(mp, tp, agno, &agbp);
1285 "%s: xfs_ialloc_read_agi() returned error %d, agno %d",
1286 __func__, error, agno);
1291 * Lookup the inode record for the given agino. If the record cannot be
1292 * found, then it's an invalid inode number and we should abort. Once
1293 * we have a record, we need to ensure it contains the inode number
1294 * we are looking up.
1296 cur = xfs_inobt_init_cursor(mp, tp, agbp, agno);
1297 error = xfs_inobt_lookup(cur, agino, XFS_LOOKUP_LE, &i);
1300 error = xfs_inobt_get_rec(cur, &rec, &i);
1301 if (!error && i == 0)
1305 xfs_trans_brelse(tp, agbp);
1306 xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
1310 /* check that the returned record contains the required inode */
1311 if (rec.ir_startino > agino ||
1312 rec.ir_startino + XFS_IALLOC_INODES(mp) <= agino)
1315 /* for untrusted inodes check it is allocated first */
1316 if ((flags & XFS_IGET_UNTRUSTED) &&
1317 (rec.ir_free & XFS_INOBT_MASK(agino - rec.ir_startino)))
1320 *chunk_agbno = XFS_AGINO_TO_AGBNO(mp, rec.ir_startino);
1321 *offset_agbno = agbno - *chunk_agbno;
1326 * Return the location of the inode in imap, for mapping it into a buffer.
1330 xfs_mount_t *mp, /* file system mount structure */
1331 xfs_trans_t *tp, /* transaction pointer */
1332 xfs_ino_t ino, /* inode to locate */
1333 struct xfs_imap *imap, /* location map structure */
1334 uint flags) /* flags for inode btree lookup */
1336 xfs_agblock_t agbno; /* block number of inode in the alloc group */
1337 xfs_agino_t agino; /* inode number within alloc group */
1338 xfs_agnumber_t agno; /* allocation group number */
1339 int blks_per_cluster; /* num blocks per inode cluster */
1340 xfs_agblock_t chunk_agbno; /* first block in inode chunk */
1341 xfs_agblock_t cluster_agbno; /* first block in inode cluster */
1342 int error; /* error code */
1343 int offset; /* index of inode in its buffer */
1344 int offset_agbno; /* blks from chunk start to inode */
1346 ASSERT(ino != NULLFSINO);
1349 * Split up the inode number into its parts.
1351 agno = XFS_INO_TO_AGNO(mp, ino);
1352 agino = XFS_INO_TO_AGINO(mp, ino);
1353 agbno = XFS_AGINO_TO_AGBNO(mp, agino);
1354 if (agno >= mp->m_sb.sb_agcount || agbno >= mp->m_sb.sb_agblocks ||
1355 ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
1358 * Don't output diagnostic information for untrusted inodes
1359 * as they can be invalid without implying corruption.
1361 if (flags & XFS_IGET_UNTRUSTED)
1362 return XFS_ERROR(EINVAL);
1363 if (agno >= mp->m_sb.sb_agcount) {
1365 "%s: agno (%d) >= mp->m_sb.sb_agcount (%d)",
1366 __func__, agno, mp->m_sb.sb_agcount);
1368 if (agbno >= mp->m_sb.sb_agblocks) {
1370 "%s: agbno (0x%llx) >= mp->m_sb.sb_agblocks (0x%lx)",
1371 __func__, (unsigned long long)agbno,
1372 (unsigned long)mp->m_sb.sb_agblocks);
1374 if (ino != XFS_AGINO_TO_INO(mp, agno, agino)) {
1376 "%s: ino (0x%llx) != XFS_AGINO_TO_INO() (0x%llx)",
1378 XFS_AGINO_TO_INO(mp, agno, agino));
1382 return XFS_ERROR(EINVAL);
1385 blks_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_blocklog;
1388 * For bulkstat and handle lookups, we have an untrusted inode number
1389 * that we have to verify is valid. We cannot do this just by reading
1390 * the inode buffer as it may have been unlinked and removed leaving
1391 * inodes in stale state on disk. Hence we have to do a btree lookup
1392 * in all cases where an untrusted inode number is passed.
1394 if (flags & XFS_IGET_UNTRUSTED) {
1395 error = xfs_imap_lookup(mp, tp, agno, agino, agbno,
1396 &chunk_agbno, &offset_agbno, flags);
1403 * If the inode cluster size is the same as the blocksize or
1404 * smaller we get to the buffer by simple arithmetics.
1406 if (XFS_INODE_CLUSTER_SIZE(mp) <= mp->m_sb.sb_blocksize) {
1407 offset = XFS_INO_TO_OFFSET(mp, ino);
1408 ASSERT(offset < mp->m_sb.sb_inopblock);
1410 imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, agbno);
1411 imap->im_len = XFS_FSB_TO_BB(mp, 1);
1412 imap->im_boffset = (ushort)(offset << mp->m_sb.sb_inodelog);
1417 * If the inode chunks are aligned then use simple maths to
1418 * find the location. Otherwise we have to do a btree
1419 * lookup to find the location.
1421 if (mp->m_inoalign_mask) {
1422 offset_agbno = agbno & mp->m_inoalign_mask;
1423 chunk_agbno = agbno - offset_agbno;
1425 error = xfs_imap_lookup(mp, tp, agno, agino, agbno,
1426 &chunk_agbno, &offset_agbno, flags);
1432 ASSERT(agbno >= chunk_agbno);
1433 cluster_agbno = chunk_agbno +
1434 ((offset_agbno / blks_per_cluster) * blks_per_cluster);
1435 offset = ((agbno - cluster_agbno) * mp->m_sb.sb_inopblock) +
1436 XFS_INO_TO_OFFSET(mp, ino);
1438 imap->im_blkno = XFS_AGB_TO_DADDR(mp, agno, cluster_agbno);
1439 imap->im_len = XFS_FSB_TO_BB(mp, blks_per_cluster);
1440 imap->im_boffset = (ushort)(offset << mp->m_sb.sb_inodelog);
1443 * If the inode number maps to a block outside the bounds
1444 * of the file system then return NULL rather than calling
1445 * read_buf and panicing when we get an error from the
1448 if ((imap->im_blkno + imap->im_len) >
1449 XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks)) {
1451 "%s: (im_blkno (0x%llx) + im_len (0x%llx)) > sb_dblocks (0x%llx)",
1452 __func__, (unsigned long long) imap->im_blkno,
1453 (unsigned long long) imap->im_len,
1454 XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks));
1455 return XFS_ERROR(EINVAL);
1461 * Compute and fill in value of m_in_maxlevels.
1464 xfs_ialloc_compute_maxlevels(
1465 xfs_mount_t *mp) /* file system mount structure */
1473 maxleafents = (1LL << XFS_INO_AGINO_BITS(mp)) >>
1474 XFS_INODES_PER_CHUNK_LOG;
1475 minleafrecs = mp->m_alloc_mnr[0];
1476 minnoderecs = mp->m_alloc_mnr[1];
1477 maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs;
1478 for (level = 1; maxblocks > 1; level++)
1479 maxblocks = (maxblocks + minnoderecs - 1) / minnoderecs;
1480 mp->m_in_maxlevels = level;
1484 * Log specified fields for the ag hdr (inode section)
1488 xfs_trans_t *tp, /* transaction pointer */
1489 xfs_buf_t *bp, /* allocation group header buffer */
1490 int fields) /* bitmask of fields to log */
1492 int first; /* first byte number */
1493 int last; /* last byte number */
1494 static const short offsets[] = { /* field starting offsets */
1495 /* keep in sync with bit definitions */
1496 offsetof(xfs_agi_t, agi_magicnum),
1497 offsetof(xfs_agi_t, agi_versionnum),
1498 offsetof(xfs_agi_t, agi_seqno),
1499 offsetof(xfs_agi_t, agi_length),
1500 offsetof(xfs_agi_t, agi_count),
1501 offsetof(xfs_agi_t, agi_root),
1502 offsetof(xfs_agi_t, agi_level),
1503 offsetof(xfs_agi_t, agi_freecount),
1504 offsetof(xfs_agi_t, agi_newino),
1505 offsetof(xfs_agi_t, agi_dirino),
1506 offsetof(xfs_agi_t, agi_unlinked),
1510 xfs_agi_t *agi; /* allocation group header */
1512 agi = XFS_BUF_TO_AGI(bp);
1513 ASSERT(agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC));
1516 * Compute byte offsets for the first and last fields.
1518 xfs_btree_offsets(fields, offsets, XFS_AGI_NUM_BITS, &first, &last);
1520 * Log the allocation group inode header buffer.
1522 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_AGI_BUF);
1523 xfs_trans_log_buf(tp, bp, first, last);
1528 xfs_check_agi_unlinked(
1529 struct xfs_agi *agi)
1533 for (i = 0; i < XFS_AGI_UNLINKED_BUCKETS; i++)
1534 ASSERT(agi->agi_unlinked[i]);
1537 #define xfs_check_agi_unlinked(agi)
1544 struct xfs_mount *mp = bp->b_target->bt_mount;
1545 struct xfs_agi *agi = XFS_BUF_TO_AGI(bp);
1547 if (xfs_sb_version_hascrc(&mp->m_sb) &&
1548 !uuid_equal(&agi->agi_uuid, &mp->m_sb.sb_uuid))
1551 * Validate the magic number of the agi block.
1553 if (agi->agi_magicnum != cpu_to_be32(XFS_AGI_MAGIC))
1555 if (!XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)))
1559 * during growfs operations, the perag is not fully initialised,
1560 * so we can't use it for any useful checking. growfs ensures we can't
1561 * use it by using uncached buffers that don't have the perag attached
1562 * so we can detect and avoid this problem.
1564 if (bp->b_pag && be32_to_cpu(agi->agi_seqno) != bp->b_pag->pag_agno)
1567 xfs_check_agi_unlinked(agi);
1572 xfs_agi_read_verify(
1575 struct xfs_mount *mp = bp->b_target->bt_mount;
1578 if (xfs_sb_version_hascrc(&mp->m_sb))
1579 agi_ok = xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
1580 offsetof(struct xfs_agi, agi_crc));
1581 agi_ok = agi_ok && xfs_agi_verify(bp);
1583 if (unlikely(XFS_TEST_ERROR(!agi_ok, mp, XFS_ERRTAG_IALLOC_READ_AGI,
1584 XFS_RANDOM_IALLOC_READ_AGI))) {
1585 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
1586 xfs_buf_ioerror(bp, EFSCORRUPTED);
1591 xfs_agi_write_verify(
1594 struct xfs_mount *mp = bp->b_target->bt_mount;
1595 struct xfs_buf_log_item *bip = bp->b_fspriv;
1597 if (!xfs_agi_verify(bp)) {
1598 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
1599 xfs_buf_ioerror(bp, EFSCORRUPTED);
1603 if (!xfs_sb_version_hascrc(&mp->m_sb))
1607 XFS_BUF_TO_AGI(bp)->agi_lsn = cpu_to_be64(bip->bli_item.li_lsn);
1608 xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length),
1609 offsetof(struct xfs_agi, agi_crc));
1612 const struct xfs_buf_ops xfs_agi_buf_ops = {
1613 .verify_read = xfs_agi_read_verify,
1614 .verify_write = xfs_agi_write_verify,
1618 * Read in the allocation group header (inode allocation section)
1622 struct xfs_mount *mp, /* file system mount structure */
1623 struct xfs_trans *tp, /* transaction pointer */
1624 xfs_agnumber_t agno, /* allocation group number */
1625 struct xfs_buf **bpp) /* allocation group hdr buf */
1629 ASSERT(agno != NULLAGNUMBER);
1631 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
1632 XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)),
1633 XFS_FSS_TO_BB(mp, 1), 0, bpp, &xfs_agi_buf_ops);
1637 ASSERT(!xfs_buf_geterror(*bpp));
1638 xfs_buf_set_ref(*bpp, XFS_AGI_REF);
1643 xfs_ialloc_read_agi(
1644 struct xfs_mount *mp, /* file system mount structure */
1645 struct xfs_trans *tp, /* transaction pointer */
1646 xfs_agnumber_t agno, /* allocation group number */
1647 struct xfs_buf **bpp) /* allocation group hdr buf */
1649 struct xfs_agi *agi; /* allocation group header */
1650 struct xfs_perag *pag; /* per allocation group data */
1653 error = xfs_read_agi(mp, tp, agno, bpp);
1657 agi = XFS_BUF_TO_AGI(*bpp);
1658 pag = xfs_perag_get(mp, agno);
1659 if (!pag->pagi_init) {
1660 pag->pagi_freecount = be32_to_cpu(agi->agi_freecount);
1661 pag->pagi_count = be32_to_cpu(agi->agi_count);
1666 * It's possible for these to be out of sync if
1667 * we are in the middle of a forced shutdown.
1669 ASSERT(pag->pagi_freecount == be32_to_cpu(agi->agi_freecount) ||
1670 XFS_FORCED_SHUTDOWN(mp));
1676 * Read in the agi to initialise the per-ag data in the mount structure
1679 xfs_ialloc_pagi_init(
1680 xfs_mount_t *mp, /* file system mount structure */
1681 xfs_trans_t *tp, /* transaction pointer */
1682 xfs_agnumber_t agno) /* allocation group number */
1684 xfs_buf_t *bp = NULL;
1687 error = xfs_ialloc_read_agi(mp, tp, agno, &bp);
1691 xfs_trans_brelse(tp, bp);