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1/*
2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18#include "xfs.h"
19#include "xfs_fs.h"
20#include "xfs_shared.h"
21#include "xfs_format.h"
22#include "xfs_log_format.h"
23#include "xfs_trans_resv.h"
24#include "xfs_bit.h"
25#include "xfs_sb.h"
26#include "xfs_mount.h"
27#include "xfs_defer.h"
28#include "xfs_da_format.h"
29#include "xfs_da_btree.h"
30#include "xfs_inode.h"
31#include "xfs_dir2.h"
32#include "xfs_ialloc.h"
33#include "xfs_alloc.h"
34#include "xfs_rtalloc.h"
35#include "xfs_bmap.h"
36#include "xfs_trans.h"
37#include "xfs_trans_priv.h"
38#include "xfs_log.h"
39#include "xfs_error.h"
40#include "xfs_quota.h"
41#include "xfs_fsops.h"
42#include "xfs_trace.h"
43#include "xfs_icache.h"
44#include "xfs_sysfs.h"
45#include "xfs_rmap_btree.h"
46#include "xfs_refcount_btree.h"
47#include "xfs_reflink.h"
48
49
50static DEFINE_MUTEX(xfs_uuid_table_mutex);
51static int xfs_uuid_table_size;
52static uuid_t *xfs_uuid_table;
53
54void
55xfs_uuid_table_free(void)
56{
57 if (xfs_uuid_table_size == 0)
58 return;
59 kmem_free(xfs_uuid_table);
60 xfs_uuid_table = NULL;
61 xfs_uuid_table_size = 0;
62}
63
64/*
65 * See if the UUID is unique among mounted XFS filesystems.
66 * Mount fails if UUID is nil or a FS with the same UUID is already mounted.
67 */
68STATIC int
69xfs_uuid_mount(
70 struct xfs_mount *mp)
71{
72 uuid_t *uuid = &mp->m_sb.sb_uuid;
73 int hole, i;
74
75 if (mp->m_flags & XFS_MOUNT_NOUUID)
76 return 0;
77
78 if (uuid_is_nil(uuid)) {
79 xfs_warn(mp, "Filesystem has nil UUID - can't mount");
80 return -EINVAL;
81 }
82
83 mutex_lock(&xfs_uuid_table_mutex);
84 for (i = 0, hole = -1; i < xfs_uuid_table_size; i++) {
85 if (uuid_is_nil(&xfs_uuid_table[i])) {
86 hole = i;
87 continue;
88 }
89 if (uuid_equal(uuid, &xfs_uuid_table[i]))
90 goto out_duplicate;
91 }
92
93 if (hole < 0) {
94 xfs_uuid_table = kmem_realloc(xfs_uuid_table,
95 (xfs_uuid_table_size + 1) * sizeof(*xfs_uuid_table),
96 KM_SLEEP);
97 hole = xfs_uuid_table_size++;
98 }
99 xfs_uuid_table[hole] = *uuid;
100 mutex_unlock(&xfs_uuid_table_mutex);
101
102 return 0;
103
104 out_duplicate:
105 mutex_unlock(&xfs_uuid_table_mutex);
106 xfs_warn(mp, "Filesystem has duplicate UUID %pU - can't mount", uuid);
107 return -EINVAL;
108}
109
110STATIC void
111xfs_uuid_unmount(
112 struct xfs_mount *mp)
113{
114 uuid_t *uuid = &mp->m_sb.sb_uuid;
115 int i;
116
117 if (mp->m_flags & XFS_MOUNT_NOUUID)
118 return;
119
120 mutex_lock(&xfs_uuid_table_mutex);
121 for (i = 0; i < xfs_uuid_table_size; i++) {
122 if (uuid_is_nil(&xfs_uuid_table[i]))
123 continue;
124 if (!uuid_equal(uuid, &xfs_uuid_table[i]))
125 continue;
126 memset(&xfs_uuid_table[i], 0, sizeof(uuid_t));
127 break;
128 }
129 ASSERT(i < xfs_uuid_table_size);
130 mutex_unlock(&xfs_uuid_table_mutex);
131}
132
133
134STATIC void
135__xfs_free_perag(
136 struct rcu_head *head)
137{
138 struct xfs_perag *pag = container_of(head, struct xfs_perag, rcu_head);
139
140 ASSERT(atomic_read(&pag->pag_ref) == 0);
141 kmem_free(pag);
142}
143
144/*
145 * Free up the per-ag resources associated with the mount structure.
146 */
147STATIC void
148xfs_free_perag(
149 xfs_mount_t *mp)
150{
151 xfs_agnumber_t agno;
152 struct xfs_perag *pag;
153
154 for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
155 spin_lock(&mp->m_perag_lock);
156 pag = radix_tree_delete(&mp->m_perag_tree, agno);
157 spin_unlock(&mp->m_perag_lock);
158 ASSERT(pag);
159 ASSERT(atomic_read(&pag->pag_ref) == 0);
160 xfs_buf_hash_destroy(pag);
161 call_rcu(&pag->rcu_head, __xfs_free_perag);
162 }
163}
164
165/*
166 * Check size of device based on the (data/realtime) block count.
167 * Note: this check is used by the growfs code as well as mount.
168 */
169int
170xfs_sb_validate_fsb_count(
171 xfs_sb_t *sbp,
172 __uint64_t nblocks)
173{
174 ASSERT(PAGE_SHIFT >= sbp->sb_blocklog);
175 ASSERT(sbp->sb_blocklog >= BBSHIFT);
176
177 /* Limited by ULONG_MAX of page cache index */
178 if (nblocks >> (PAGE_SHIFT - sbp->sb_blocklog) > ULONG_MAX)
179 return -EFBIG;
180 return 0;
181}
182
183int
184xfs_initialize_perag(
185 xfs_mount_t *mp,
186 xfs_agnumber_t agcount,
187 xfs_agnumber_t *maxagi)
188{
189 xfs_agnumber_t index;
190 xfs_agnumber_t first_initialised = NULLAGNUMBER;
191 xfs_perag_t *pag;
192 int error = -ENOMEM;
193
194 /*
195 * Walk the current per-ag tree so we don't try to initialise AGs
196 * that already exist (growfs case). Allocate and insert all the
197 * AGs we don't find ready for initialisation.
198 */
199 for (index = 0; index < agcount; index++) {
200 pag = xfs_perag_get(mp, index);
201 if (pag) {
202 xfs_perag_put(pag);
203 continue;
204 }
205
206 pag = kmem_zalloc(sizeof(*pag), KM_MAYFAIL);
207 if (!pag)
208 goto out_unwind_new_pags;
209 pag->pag_agno = index;
210 pag->pag_mount = mp;
211 spin_lock_init(&pag->pag_ici_lock);
212 mutex_init(&pag->pag_ici_reclaim_lock);
213 INIT_RADIX_TREE(&pag->pag_ici_root, GFP_ATOMIC);
214 if (xfs_buf_hash_init(pag))
215 goto out_free_pag;
216
217 if (radix_tree_preload(GFP_NOFS))
218 goto out_hash_destroy;
219
220 spin_lock(&mp->m_perag_lock);
221 if (radix_tree_insert(&mp->m_perag_tree, index, pag)) {
222 BUG();
223 spin_unlock(&mp->m_perag_lock);
224 radix_tree_preload_end();
225 error = -EEXIST;
226 goto out_hash_destroy;
227 }
228 spin_unlock(&mp->m_perag_lock);
229 radix_tree_preload_end();
230 /* first new pag is fully initialized */
231 if (first_initialised == NULLAGNUMBER)
232 first_initialised = index;
233 }
234
235 index = xfs_set_inode_alloc(mp, agcount);
236
237 if (maxagi)
238 *maxagi = index;
239
240 mp->m_ag_prealloc_blocks = xfs_prealloc_blocks(mp);
241 return 0;
242
243out_hash_destroy:
244 xfs_buf_hash_destroy(pag);
245out_free_pag:
246 kmem_free(pag);
247out_unwind_new_pags:
248 /* unwind any prior newly initialized pags */
249 for (index = first_initialised; index < agcount; index++) {
250 pag = radix_tree_delete(&mp->m_perag_tree, index);
251 if (!pag)
252 break;
253 xfs_buf_hash_destroy(pag);
254 kmem_free(pag);
255 }
256 return error;
257}
258
259/*
260 * xfs_readsb
261 *
262 * Does the initial read of the superblock.
263 */
264int
265xfs_readsb(
266 struct xfs_mount *mp,
267 int flags)
268{
269 unsigned int sector_size;
270 struct xfs_buf *bp;
271 struct xfs_sb *sbp = &mp->m_sb;
272 int error;
273 int loud = !(flags & XFS_MFSI_QUIET);
274 const struct xfs_buf_ops *buf_ops;
275
276 ASSERT(mp->m_sb_bp == NULL);
277 ASSERT(mp->m_ddev_targp != NULL);
278
279 /*
280 * For the initial read, we must guess at the sector
281 * size based on the block device. It's enough to
282 * get the sb_sectsize out of the superblock and
283 * then reread with the proper length.
284 * We don't verify it yet, because it may not be complete.
285 */
286 sector_size = xfs_getsize_buftarg(mp->m_ddev_targp);
287 buf_ops = NULL;
288
289 /*
290 * Allocate a (locked) buffer to hold the superblock. This will be kept
291 * around at all times to optimize access to the superblock. Therefore,
292 * set XBF_NO_IOACCT to make sure it doesn't hold the buftarg count
293 * elevated.
294 */
295reread:
296 error = xfs_buf_read_uncached(mp->m_ddev_targp, XFS_SB_DADDR,
297 BTOBB(sector_size), XBF_NO_IOACCT, &bp,
298 buf_ops);
299 if (error) {
300 if (loud)
301 xfs_warn(mp, "SB validate failed with error %d.", error);
302 /* bad CRC means corrupted metadata */
303 if (error == -EFSBADCRC)
304 error = -EFSCORRUPTED;
305 return error;
306 }
307
308 /*
309 * Initialize the mount structure from the superblock.
310 */
311 xfs_sb_from_disk(sbp, XFS_BUF_TO_SBP(bp));
312
313 /*
314 * If we haven't validated the superblock, do so now before we try
315 * to check the sector size and reread the superblock appropriately.
316 */
317 if (sbp->sb_magicnum != XFS_SB_MAGIC) {
318 if (loud)
319 xfs_warn(mp, "Invalid superblock magic number");
320 error = -EINVAL;
321 goto release_buf;
322 }
323
324 /*
325 * We must be able to do sector-sized and sector-aligned IO.
326 */
327 if (sector_size > sbp->sb_sectsize) {
328 if (loud)
329 xfs_warn(mp, "device supports %u byte sectors (not %u)",
330 sector_size, sbp->sb_sectsize);
331 error = -ENOSYS;
332 goto release_buf;
333 }
334
335 if (buf_ops == NULL) {
336 /*
337 * Re-read the superblock so the buffer is correctly sized,
338 * and properly verified.
339 */
340 xfs_buf_relse(bp);
341 sector_size = sbp->sb_sectsize;
342 buf_ops = loud ? &xfs_sb_buf_ops : &xfs_sb_quiet_buf_ops;
343 goto reread;
344 }
345
346 xfs_reinit_percpu_counters(mp);
347
348 /* no need to be quiet anymore, so reset the buf ops */
349 bp->b_ops = &xfs_sb_buf_ops;
350
351 mp->m_sb_bp = bp;
352 xfs_buf_unlock(bp);
353 return 0;
354
355release_buf:
356 xfs_buf_relse(bp);
357 return error;
358}
359
360/*
361 * Update alignment values based on mount options and sb values
362 */
363STATIC int
364xfs_update_alignment(xfs_mount_t *mp)
365{
366 xfs_sb_t *sbp = &(mp->m_sb);
367
368 if (mp->m_dalign) {
369 /*
370 * If stripe unit and stripe width are not multiples
371 * of the fs blocksize turn off alignment.
372 */
373 if ((BBTOB(mp->m_dalign) & mp->m_blockmask) ||
374 (BBTOB(mp->m_swidth) & mp->m_blockmask)) {
375 xfs_warn(mp,
376 "alignment check failed: sunit/swidth vs. blocksize(%d)",
377 sbp->sb_blocksize);
378 return -EINVAL;
379 } else {
380 /*
381 * Convert the stripe unit and width to FSBs.
382 */
383 mp->m_dalign = XFS_BB_TO_FSBT(mp, mp->m_dalign);
384 if (mp->m_dalign && (sbp->sb_agblocks % mp->m_dalign)) {
385 xfs_warn(mp,
386 "alignment check failed: sunit/swidth vs. agsize(%d)",
387 sbp->sb_agblocks);
388 return -EINVAL;
389 } else if (mp->m_dalign) {
390 mp->m_swidth = XFS_BB_TO_FSBT(mp, mp->m_swidth);
391 } else {
392 xfs_warn(mp,
393 "alignment check failed: sunit(%d) less than bsize(%d)",
394 mp->m_dalign, sbp->sb_blocksize);
395 return -EINVAL;
396 }
397 }
398
399 /*
400 * Update superblock with new values
401 * and log changes
402 */
403 if (xfs_sb_version_hasdalign(sbp)) {
404 if (sbp->sb_unit != mp->m_dalign) {
405 sbp->sb_unit = mp->m_dalign;
406 mp->m_update_sb = true;
407 }
408 if (sbp->sb_width != mp->m_swidth) {
409 sbp->sb_width = mp->m_swidth;
410 mp->m_update_sb = true;
411 }
412 } else {
413 xfs_warn(mp,
414 "cannot change alignment: superblock does not support data alignment");
415 return -EINVAL;
416 }
417 } else if ((mp->m_flags & XFS_MOUNT_NOALIGN) != XFS_MOUNT_NOALIGN &&
418 xfs_sb_version_hasdalign(&mp->m_sb)) {
419 mp->m_dalign = sbp->sb_unit;
420 mp->m_swidth = sbp->sb_width;
421 }
422
423 return 0;
424}
425
426/*
427 * Set the maximum inode count for this filesystem
428 */
429STATIC void
430xfs_set_maxicount(xfs_mount_t *mp)
431{
432 xfs_sb_t *sbp = &(mp->m_sb);
433 __uint64_t icount;
434
435 if (sbp->sb_imax_pct) {
436 /*
437 * Make sure the maximum inode count is a multiple
438 * of the units we allocate inodes in.
439 */
440 icount = sbp->sb_dblocks * sbp->sb_imax_pct;
441 do_div(icount, 100);
442 do_div(icount, mp->m_ialloc_blks);
443 mp->m_maxicount = (icount * mp->m_ialloc_blks) <<
444 sbp->sb_inopblog;
445 } else {
446 mp->m_maxicount = 0;
447 }
448}
449
450/*
451 * Set the default minimum read and write sizes unless
452 * already specified in a mount option.
453 * We use smaller I/O sizes when the file system
454 * is being used for NFS service (wsync mount option).
455 */
456STATIC void
457xfs_set_rw_sizes(xfs_mount_t *mp)
458{
459 xfs_sb_t *sbp = &(mp->m_sb);
460 int readio_log, writeio_log;
461
462 if (!(mp->m_flags & XFS_MOUNT_DFLT_IOSIZE)) {
463 if (mp->m_flags & XFS_MOUNT_WSYNC) {
464 readio_log = XFS_WSYNC_READIO_LOG;
465 writeio_log = XFS_WSYNC_WRITEIO_LOG;
466 } else {
467 readio_log = XFS_READIO_LOG_LARGE;
468 writeio_log = XFS_WRITEIO_LOG_LARGE;
469 }
470 } else {
471 readio_log = mp->m_readio_log;
472 writeio_log = mp->m_writeio_log;
473 }
474
475 if (sbp->sb_blocklog > readio_log) {
476 mp->m_readio_log = sbp->sb_blocklog;
477 } else {
478 mp->m_readio_log = readio_log;
479 }
480 mp->m_readio_blocks = 1 << (mp->m_readio_log - sbp->sb_blocklog);
481 if (sbp->sb_blocklog > writeio_log) {
482 mp->m_writeio_log = sbp->sb_blocklog;
483 } else {
484 mp->m_writeio_log = writeio_log;
485 }
486 mp->m_writeio_blocks = 1 << (mp->m_writeio_log - sbp->sb_blocklog);
487}
488
489/*
490 * precalculate the low space thresholds for dynamic speculative preallocation.
491 */
492void
493xfs_set_low_space_thresholds(
494 struct xfs_mount *mp)
495{
496 int i;
497
498 for (i = 0; i < XFS_LOWSP_MAX; i++) {
499 __uint64_t space = mp->m_sb.sb_dblocks;
500
501 do_div(space, 100);
502 mp->m_low_space[i] = space * (i + 1);
503 }
504}
505
506
507/*
508 * Set whether we're using inode alignment.
509 */
510STATIC void
511xfs_set_inoalignment(xfs_mount_t *mp)
512{
513 if (xfs_sb_version_hasalign(&mp->m_sb) &&
514 mp->m_sb.sb_inoalignmt >= xfs_icluster_size_fsb(mp))
515 mp->m_inoalign_mask = mp->m_sb.sb_inoalignmt - 1;
516 else
517 mp->m_inoalign_mask = 0;
518 /*
519 * If we are using stripe alignment, check whether
520 * the stripe unit is a multiple of the inode alignment
521 */
522 if (mp->m_dalign && mp->m_inoalign_mask &&
523 !(mp->m_dalign & mp->m_inoalign_mask))
524 mp->m_sinoalign = mp->m_dalign;
525 else
526 mp->m_sinoalign = 0;
527}
528
529/*
530 * Check that the data (and log if separate) is an ok size.
531 */
532STATIC int
533xfs_check_sizes(
534 struct xfs_mount *mp)
535{
536 struct xfs_buf *bp;
537 xfs_daddr_t d;
538 int error;
539
540 d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks);
541 if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_dblocks) {
542 xfs_warn(mp, "filesystem size mismatch detected");
543 return -EFBIG;
544 }
545 error = xfs_buf_read_uncached(mp->m_ddev_targp,
546 d - XFS_FSS_TO_BB(mp, 1),
547 XFS_FSS_TO_BB(mp, 1), 0, &bp, NULL);
548 if (error) {
549 xfs_warn(mp, "last sector read failed");
550 return error;
551 }
552 xfs_buf_relse(bp);
553
554 if (mp->m_logdev_targp == mp->m_ddev_targp)
555 return 0;
556
557 d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_logblocks);
558 if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_logblocks) {
559 xfs_warn(mp, "log size mismatch detected");
560 return -EFBIG;
561 }
562 error = xfs_buf_read_uncached(mp->m_logdev_targp,
563 d - XFS_FSB_TO_BB(mp, 1),
564 XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
565 if (error) {
566 xfs_warn(mp, "log device read failed");
567 return error;
568 }
569 xfs_buf_relse(bp);
570 return 0;
571}
572
573/*
574 * Clear the quotaflags in memory and in the superblock.
575 */
576int
577xfs_mount_reset_sbqflags(
578 struct xfs_mount *mp)
579{
580 mp->m_qflags = 0;
581
582 /* It is OK to look at sb_qflags in the mount path without m_sb_lock. */
583 if (mp->m_sb.sb_qflags == 0)
584 return 0;
585 spin_lock(&mp->m_sb_lock);
586 mp->m_sb.sb_qflags = 0;
587 spin_unlock(&mp->m_sb_lock);
588
589 if (!xfs_fs_writable(mp, SB_FREEZE_WRITE))
590 return 0;
591
592 return xfs_sync_sb(mp, false);
593}
594
595__uint64_t
596xfs_default_resblks(xfs_mount_t *mp)
597{
598 __uint64_t resblks;
599
600 /*
601 * We default to 5% or 8192 fsbs of space reserved, whichever is
602 * smaller. This is intended to cover concurrent allocation
603 * transactions when we initially hit enospc. These each require a 4
604 * block reservation. Hence by default we cover roughly 2000 concurrent
605 * allocation reservations.
606 */
607 resblks = mp->m_sb.sb_dblocks;
608 do_div(resblks, 20);
609 resblks = min_t(__uint64_t, resblks, 8192);
610 return resblks;
611}
612
613/*
614 * This function does the following on an initial mount of a file system:
615 * - reads the superblock from disk and init the mount struct
616 * - if we're a 32-bit kernel, do a size check on the superblock
617 * so we don't mount terabyte filesystems
618 * - init mount struct realtime fields
619 * - allocate inode hash table for fs
620 * - init directory manager
621 * - perform recovery and init the log manager
622 */
623int
624xfs_mountfs(
625 struct xfs_mount *mp)
626{
627 struct xfs_sb *sbp = &(mp->m_sb);
628 struct xfs_inode *rip;
629 __uint64_t resblks;
630 uint quotamount = 0;
631 uint quotaflags = 0;
632 int error = 0;
633
634 xfs_sb_mount_common(mp, sbp);
635
636 /*
637 * Check for a mismatched features2 values. Older kernels read & wrote
638 * into the wrong sb offset for sb_features2 on some platforms due to
639 * xfs_sb_t not being 64bit size aligned when sb_features2 was added,
640 * which made older superblock reading/writing routines swap it as a
641 * 64-bit value.
642 *
643 * For backwards compatibility, we make both slots equal.
644 *
645 * If we detect a mismatched field, we OR the set bits into the existing
646 * features2 field in case it has already been modified; we don't want
647 * to lose any features. We then update the bad location with the ORed
648 * value so that older kernels will see any features2 flags. The
649 * superblock writeback code ensures the new sb_features2 is copied to
650 * sb_bad_features2 before it is logged or written to disk.
651 */
652 if (xfs_sb_has_mismatched_features2(sbp)) {
653 xfs_warn(mp, "correcting sb_features alignment problem");
654 sbp->sb_features2 |= sbp->sb_bad_features2;
655 mp->m_update_sb = true;
656
657 /*
658 * Re-check for ATTR2 in case it was found in bad_features2
659 * slot.
660 */
661 if (xfs_sb_version_hasattr2(&mp->m_sb) &&
662 !(mp->m_flags & XFS_MOUNT_NOATTR2))
663 mp->m_flags |= XFS_MOUNT_ATTR2;
664 }
665
666 if (xfs_sb_version_hasattr2(&mp->m_sb) &&
667 (mp->m_flags & XFS_MOUNT_NOATTR2)) {
668 xfs_sb_version_removeattr2(&mp->m_sb);
669 mp->m_update_sb = true;
670
671 /* update sb_versionnum for the clearing of the morebits */
672 if (!sbp->sb_features2)
673 mp->m_update_sb = true;
674 }
675
676 /* always use v2 inodes by default now */
677 if (!(mp->m_sb.sb_versionnum & XFS_SB_VERSION_NLINKBIT)) {
678 mp->m_sb.sb_versionnum |= XFS_SB_VERSION_NLINKBIT;
679 mp->m_update_sb = true;
680 }
681
682 /*
683 * Check if sb_agblocks is aligned at stripe boundary
684 * If sb_agblocks is NOT aligned turn off m_dalign since
685 * allocator alignment is within an ag, therefore ag has
686 * to be aligned at stripe boundary.
687 */
688 error = xfs_update_alignment(mp);
689 if (error)
690 goto out;
691
692 xfs_alloc_compute_maxlevels(mp);
693 xfs_bmap_compute_maxlevels(mp, XFS_DATA_FORK);
694 xfs_bmap_compute_maxlevels(mp, XFS_ATTR_FORK);
695 xfs_ialloc_compute_maxlevels(mp);
696 xfs_rmapbt_compute_maxlevels(mp);
697 xfs_refcountbt_compute_maxlevels(mp);
698
699 xfs_set_maxicount(mp);
700
701 /* enable fail_at_unmount as default */
702 mp->m_fail_unmount = 1;
703
704 error = xfs_sysfs_init(&mp->m_kobj, &xfs_mp_ktype, NULL, mp->m_fsname);
705 if (error)
706 goto out;
707
708 error = xfs_sysfs_init(&mp->m_stats.xs_kobj, &xfs_stats_ktype,
709 &mp->m_kobj, "stats");
710 if (error)
711 goto out_remove_sysfs;
712
713 error = xfs_error_sysfs_init(mp);
714 if (error)
715 goto out_del_stats;
716
717
718 error = xfs_uuid_mount(mp);
719 if (error)
720 goto out_remove_error_sysfs;
721
722 /*
723 * Set the minimum read and write sizes
724 */
725 xfs_set_rw_sizes(mp);
726
727 /* set the low space thresholds for dynamic preallocation */
728 xfs_set_low_space_thresholds(mp);
729
730 /*
731 * Set the inode cluster size.
732 * This may still be overridden by the file system
733 * block size if it is larger than the chosen cluster size.
734 *
735 * For v5 filesystems, scale the cluster size with the inode size to
736 * keep a constant ratio of inode per cluster buffer, but only if mkfs
737 * has set the inode alignment value appropriately for larger cluster
738 * sizes.
739 */
740 mp->m_inode_cluster_size = XFS_INODE_BIG_CLUSTER_SIZE;
741 if (xfs_sb_version_hascrc(&mp->m_sb)) {
742 int new_size = mp->m_inode_cluster_size;
743
744 new_size *= mp->m_sb.sb_inodesize / XFS_DINODE_MIN_SIZE;
745 if (mp->m_sb.sb_inoalignmt >= XFS_B_TO_FSBT(mp, new_size))
746 mp->m_inode_cluster_size = new_size;
747 }
748
749 /*
750 * If enabled, sparse inode chunk alignment is expected to match the
751 * cluster size. Full inode chunk alignment must match the chunk size,
752 * but that is checked on sb read verification...
753 */
754 if (xfs_sb_version_hassparseinodes(&mp->m_sb) &&
755 mp->m_sb.sb_spino_align !=
756 XFS_B_TO_FSBT(mp, mp->m_inode_cluster_size)) {
757 xfs_warn(mp,
758 "Sparse inode block alignment (%u) must match cluster size (%llu).",
759 mp->m_sb.sb_spino_align,
760 XFS_B_TO_FSBT(mp, mp->m_inode_cluster_size));
761 error = -EINVAL;
762 goto out_remove_uuid;
763 }
764
765 /*
766 * Set inode alignment fields
767 */
768 xfs_set_inoalignment(mp);
769
770 /*
771 * Check that the data (and log if separate) is an ok size.
772 */
773 error = xfs_check_sizes(mp);
774 if (error)
775 goto out_remove_uuid;
776
777 /*
778 * Initialize realtime fields in the mount structure
779 */
780 error = xfs_rtmount_init(mp);
781 if (error) {
782 xfs_warn(mp, "RT mount failed");
783 goto out_remove_uuid;
784 }
785
786 /*
787 * Copies the low order bits of the timestamp and the randomly
788 * set "sequence" number out of a UUID.
789 */
790 uuid_getnodeuniq(&sbp->sb_uuid, mp->m_fixedfsid);
791
792 mp->m_dmevmask = 0; /* not persistent; set after each mount */
793
794 error = xfs_da_mount(mp);
795 if (error) {
796 xfs_warn(mp, "Failed dir/attr init: %d", error);
797 goto out_remove_uuid;
798 }
799
800 /*
801 * Initialize the precomputed transaction reservations values.
802 */
803 xfs_trans_init(mp);
804
805 /*
806 * Allocate and initialize the per-ag data.
807 */
808 spin_lock_init(&mp->m_perag_lock);
809 INIT_RADIX_TREE(&mp->m_perag_tree, GFP_ATOMIC);
810 error = xfs_initialize_perag(mp, sbp->sb_agcount, &mp->m_maxagi);
811 if (error) {
812 xfs_warn(mp, "Failed per-ag init: %d", error);
813 goto out_free_dir;
814 }
815
816 if (!sbp->sb_logblocks) {
817 xfs_warn(mp, "no log defined");
818 XFS_ERROR_REPORT("xfs_mountfs", XFS_ERRLEVEL_LOW, mp);
819 error = -EFSCORRUPTED;
820 goto out_free_perag;
821 }
822
823 /*
824 * Log's mount-time initialization. The first part of recovery can place
825 * some items on the AIL, to be handled when recovery is finished or
826 * cancelled.
827 */
828 error = xfs_log_mount(mp, mp->m_logdev_targp,
829 XFS_FSB_TO_DADDR(mp, sbp->sb_logstart),
830 XFS_FSB_TO_BB(mp, sbp->sb_logblocks));
831 if (error) {
832 xfs_warn(mp, "log mount failed");
833 goto out_fail_wait;
834 }
835
836 /*
837 * Now the log is mounted, we know if it was an unclean shutdown or
838 * not. If it was, with the first phase of recovery has completed, we
839 * have consistent AG blocks on disk. We have not recovered EFIs yet,
840 * but they are recovered transactionally in the second recovery phase
841 * later.
842 *
843 * Hence we can safely re-initialise incore superblock counters from
844 * the per-ag data. These may not be correct if the filesystem was not
845 * cleanly unmounted, so we need to wait for recovery to finish before
846 * doing this.
847 *
848 * If the filesystem was cleanly unmounted, then we can trust the
849 * values in the superblock to be correct and we don't need to do
850 * anything here.
851 *
852 * If we are currently making the filesystem, the initialisation will
853 * fail as the perag data is in an undefined state.
854 */
855 if (xfs_sb_version_haslazysbcount(&mp->m_sb) &&
856 !XFS_LAST_UNMOUNT_WAS_CLEAN(mp) &&
857 !mp->m_sb.sb_inprogress) {
858 error = xfs_initialize_perag_data(mp, sbp->sb_agcount);
859 if (error)
860 goto out_log_dealloc;
861 }
862
863 /*
864 * Get and sanity-check the root inode.
865 * Save the pointer to it in the mount structure.
866 */
867 error = xfs_iget(mp, NULL, sbp->sb_rootino, 0, XFS_ILOCK_EXCL, &rip);
868 if (error) {
869 xfs_warn(mp, "failed to read root inode");
870 goto out_log_dealloc;
871 }
872
873 ASSERT(rip != NULL);
874
875 if (unlikely(!S_ISDIR(VFS_I(rip)->i_mode))) {
876 xfs_warn(mp, "corrupted root inode %llu: not a directory",
877 (unsigned long long)rip->i_ino);
878 xfs_iunlock(rip, XFS_ILOCK_EXCL);
879 XFS_ERROR_REPORT("xfs_mountfs_int(2)", XFS_ERRLEVEL_LOW,
880 mp);
881 error = -EFSCORRUPTED;
882 goto out_rele_rip;
883 }
884 mp->m_rootip = rip; /* save it */
885
886 xfs_iunlock(rip, XFS_ILOCK_EXCL);
887
888 /*
889 * Initialize realtime inode pointers in the mount structure
890 */
891 error = xfs_rtmount_inodes(mp);
892 if (error) {
893 /*
894 * Free up the root inode.
895 */
896 xfs_warn(mp, "failed to read RT inodes");
897 goto out_rele_rip;
898 }
899
900 /*
901 * If this is a read-only mount defer the superblock updates until
902 * the next remount into writeable mode. Otherwise we would never
903 * perform the update e.g. for the root filesystem.
904 */
905 if (mp->m_update_sb && !(mp->m_flags & XFS_MOUNT_RDONLY)) {
906 error = xfs_sync_sb(mp, false);
907 if (error) {
908 xfs_warn(mp, "failed to write sb changes");
909 goto out_rtunmount;
910 }
911 }
912
913 /*
914 * Initialise the XFS quota management subsystem for this mount
915 */
916 if (XFS_IS_QUOTA_RUNNING(mp)) {
917 error = xfs_qm_newmount(mp, "amount, "aflags);
918 if (error)
919 goto out_rtunmount;
920 } else {
921 ASSERT(!XFS_IS_QUOTA_ON(mp));
922
923 /*
924 * If a file system had quotas running earlier, but decided to
925 * mount without -o uquota/pquota/gquota options, revoke the
926 * quotachecked license.
927 */
928 if (mp->m_sb.sb_qflags & XFS_ALL_QUOTA_ACCT) {
929 xfs_notice(mp, "resetting quota flags");
930 error = xfs_mount_reset_sbqflags(mp);
931 if (error)
932 goto out_rtunmount;
933 }
934 }
935
936 /*
937 * During the second phase of log recovery, we need iget and
938 * iput to behave like they do for an active filesystem.
939 * xfs_fs_drop_inode needs to be able to prevent the deletion
940 * of inodes before we're done replaying log items on those
941 * inodes.
942 */
943 mp->m_super->s_flags |= MS_ACTIVE;
944
945 /*
946 * Finish recovering the file system. This part needed to be delayed
947 * until after the root and real-time bitmap inodes were consistently
948 * read in.
949 */
950 error = xfs_log_mount_finish(mp);
951 if (error) {
952 xfs_warn(mp, "log mount finish failed");
953 goto out_rtunmount;
954 }
955
956 /*
957 * Now the log is fully replayed, we can transition to full read-only
958 * mode for read-only mounts. This will sync all the metadata and clean
959 * the log so that the recovery we just performed does not have to be
960 * replayed again on the next mount.
961 *
962 * We use the same quiesce mechanism as the rw->ro remount, as they are
963 * semantically identical operations.
964 */
965 if ((mp->m_flags & (XFS_MOUNT_RDONLY|XFS_MOUNT_NORECOVERY)) ==
966 XFS_MOUNT_RDONLY) {
967 xfs_quiesce_attr(mp);
968 }
969
970 /*
971 * Complete the quota initialisation, post-log-replay component.
972 */
973 if (quotamount) {
974 ASSERT(mp->m_qflags == 0);
975 mp->m_qflags = quotaflags;
976
977 xfs_qm_mount_quotas(mp);
978 }
979
980 /*
981 * Now we are mounted, reserve a small amount of unused space for
982 * privileged transactions. This is needed so that transaction
983 * space required for critical operations can dip into this pool
984 * when at ENOSPC. This is needed for operations like create with
985 * attr, unwritten extent conversion at ENOSPC, etc. Data allocations
986 * are not allowed to use this reserved space.
987 *
988 * This may drive us straight to ENOSPC on mount, but that implies
989 * we were already there on the last unmount. Warn if this occurs.
990 */
991 if (!(mp->m_flags & XFS_MOUNT_RDONLY)) {
992 resblks = xfs_default_resblks(mp);
993 error = xfs_reserve_blocks(mp, &resblks, NULL);
994 if (error)
995 xfs_warn(mp,
996 "Unable to allocate reserve blocks. Continuing without reserve pool.");
997
998 /* Recover any CoW blocks that never got remapped. */
999 error = xfs_reflink_recover_cow(mp);
1000 if (error) {
1001 xfs_err(mp,
1002 "Error %d recovering leftover CoW allocations.", error);
1003 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1004 goto out_quota;
1005 }
1006
1007 /* Reserve AG blocks for future btree expansion. */
1008 error = xfs_fs_reserve_ag_blocks(mp);
1009 if (error && error != -ENOSPC)
1010 goto out_agresv;
1011 }
1012
1013 return 0;
1014
1015 out_agresv:
1016 xfs_fs_unreserve_ag_blocks(mp);
1017 out_quota:
1018 xfs_qm_unmount_quotas(mp);
1019 out_rtunmount:
1020 mp->m_super->s_flags &= ~MS_ACTIVE;
1021 xfs_rtunmount_inodes(mp);
1022 out_rele_rip:
1023 IRELE(rip);
1024 cancel_delayed_work_sync(&mp->m_reclaim_work);
1025 xfs_reclaim_inodes(mp, SYNC_WAIT);
1026 out_log_dealloc:
1027 mp->m_flags |= XFS_MOUNT_UNMOUNTING;
1028 xfs_log_mount_cancel(mp);
1029 out_fail_wait:
1030 if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp)
1031 xfs_wait_buftarg(mp->m_logdev_targp);
1032 xfs_wait_buftarg(mp->m_ddev_targp);
1033 out_free_perag:
1034 xfs_free_perag(mp);
1035 out_free_dir:
1036 xfs_da_unmount(mp);
1037 out_remove_uuid:
1038 xfs_uuid_unmount(mp);
1039 out_remove_error_sysfs:
1040 xfs_error_sysfs_del(mp);
1041 out_del_stats:
1042 xfs_sysfs_del(&mp->m_stats.xs_kobj);
1043 out_remove_sysfs:
1044 xfs_sysfs_del(&mp->m_kobj);
1045 out:
1046 return error;
1047}
1048
1049/*
1050 * This flushes out the inodes,dquots and the superblock, unmounts the
1051 * log and makes sure that incore structures are freed.
1052 */
1053void
1054xfs_unmountfs(
1055 struct xfs_mount *mp)
1056{
1057 __uint64_t resblks;
1058 int error;
1059
1060 cancel_delayed_work_sync(&mp->m_eofblocks_work);
1061 cancel_delayed_work_sync(&mp->m_cowblocks_work);
1062
1063 xfs_fs_unreserve_ag_blocks(mp);
1064 xfs_qm_unmount_quotas(mp);
1065 xfs_rtunmount_inodes(mp);
1066 IRELE(mp->m_rootip);
1067
1068 /*
1069 * We can potentially deadlock here if we have an inode cluster
1070 * that has been freed has its buffer still pinned in memory because
1071 * the transaction is still sitting in a iclog. The stale inodes
1072 * on that buffer will have their flush locks held until the
1073 * transaction hits the disk and the callbacks run. the inode
1074 * flush takes the flush lock unconditionally and with nothing to
1075 * push out the iclog we will never get that unlocked. hence we
1076 * need to force the log first.
1077 */
1078 xfs_log_force(mp, XFS_LOG_SYNC);
1079
1080 /*
1081 * We now need to tell the world we are unmounting. This will allow
1082 * us to detect that the filesystem is going away and we should error
1083 * out anything that we have been retrying in the background. This will
1084 * prevent neverending retries in AIL pushing from hanging the unmount.
1085 */
1086 mp->m_flags |= XFS_MOUNT_UNMOUNTING;
1087
1088 /*
1089 * Flush all pending changes from the AIL.
1090 */
1091 xfs_ail_push_all_sync(mp->m_ail);
1092
1093 /*
1094 * And reclaim all inodes. At this point there should be no dirty
1095 * inodes and none should be pinned or locked, but use synchronous
1096 * reclaim just to be sure. We can stop background inode reclaim
1097 * here as well if it is still running.
1098 */
1099 cancel_delayed_work_sync(&mp->m_reclaim_work);
1100 xfs_reclaim_inodes(mp, SYNC_WAIT);
1101
1102 xfs_qm_unmount(mp);
1103
1104 /*
1105 * Unreserve any blocks we have so that when we unmount we don't account
1106 * the reserved free space as used. This is really only necessary for
1107 * lazy superblock counting because it trusts the incore superblock
1108 * counters to be absolutely correct on clean unmount.
1109 *
1110 * We don't bother correcting this elsewhere for lazy superblock
1111 * counting because on mount of an unclean filesystem we reconstruct the
1112 * correct counter value and this is irrelevant.
1113 *
1114 * For non-lazy counter filesystems, this doesn't matter at all because
1115 * we only every apply deltas to the superblock and hence the incore
1116 * value does not matter....
1117 */
1118 resblks = 0;
1119 error = xfs_reserve_blocks(mp, &resblks, NULL);
1120 if (error)
1121 xfs_warn(mp, "Unable to free reserved block pool. "
1122 "Freespace may not be correct on next mount.");
1123
1124 error = xfs_log_sbcount(mp);
1125 if (error)
1126 xfs_warn(mp, "Unable to update superblock counters. "
1127 "Freespace may not be correct on next mount.");
1128
1129
1130 xfs_log_unmount(mp);
1131 xfs_da_unmount(mp);
1132 xfs_uuid_unmount(mp);
1133
1134#if defined(DEBUG)
1135 xfs_errortag_clearall(mp, 0);
1136#endif
1137 xfs_free_perag(mp);
1138
1139 xfs_error_sysfs_del(mp);
1140 xfs_sysfs_del(&mp->m_stats.xs_kobj);
1141 xfs_sysfs_del(&mp->m_kobj);
1142}
1143
1144/*
1145 * Determine whether modifications can proceed. The caller specifies the minimum
1146 * freeze level for which modifications should not be allowed. This allows
1147 * certain operations to proceed while the freeze sequence is in progress, if
1148 * necessary.
1149 */
1150bool
1151xfs_fs_writable(
1152 struct xfs_mount *mp,
1153 int level)
1154{
1155 ASSERT(level > SB_UNFROZEN);
1156 if ((mp->m_super->s_writers.frozen >= level) ||
1157 XFS_FORCED_SHUTDOWN(mp) || (mp->m_flags & XFS_MOUNT_RDONLY))
1158 return false;
1159
1160 return true;
1161}
1162
1163/*
1164 * xfs_log_sbcount
1165 *
1166 * Sync the superblock counters to disk.
1167 *
1168 * Note this code can be called during the process of freezing, so we use the
1169 * transaction allocator that does not block when the transaction subsystem is
1170 * in its frozen state.
1171 */
1172int
1173xfs_log_sbcount(xfs_mount_t *mp)
1174{
1175 /* allow this to proceed during the freeze sequence... */
1176 if (!xfs_fs_writable(mp, SB_FREEZE_COMPLETE))
1177 return 0;
1178
1179 /*
1180 * we don't need to do this if we are updating the superblock
1181 * counters on every modification.
1182 */
1183 if (!xfs_sb_version_haslazysbcount(&mp->m_sb))
1184 return 0;
1185
1186 return xfs_sync_sb(mp, true);
1187}
1188
1189/*
1190 * Deltas for the inode count are +/-64, hence we use a large batch size
1191 * of 128 so we don't need to take the counter lock on every update.
1192 */
1193#define XFS_ICOUNT_BATCH 128
1194int
1195xfs_mod_icount(
1196 struct xfs_mount *mp,
1197 int64_t delta)
1198{
1199 __percpu_counter_add(&mp->m_icount, delta, XFS_ICOUNT_BATCH);
1200 if (__percpu_counter_compare(&mp->m_icount, 0, XFS_ICOUNT_BATCH) < 0) {
1201 ASSERT(0);
1202 percpu_counter_add(&mp->m_icount, -delta);
1203 return -EINVAL;
1204 }
1205 return 0;
1206}
1207
1208int
1209xfs_mod_ifree(
1210 struct xfs_mount *mp,
1211 int64_t delta)
1212{
1213 percpu_counter_add(&mp->m_ifree, delta);
1214 if (percpu_counter_compare(&mp->m_ifree, 0) < 0) {
1215 ASSERT(0);
1216 percpu_counter_add(&mp->m_ifree, -delta);
1217 return -EINVAL;
1218 }
1219 return 0;
1220}
1221
1222/*
1223 * Deltas for the block count can vary from 1 to very large, but lock contention
1224 * only occurs on frequent small block count updates such as in the delayed
1225 * allocation path for buffered writes (page a time updates). Hence we set
1226 * a large batch count (1024) to minimise global counter updates except when
1227 * we get near to ENOSPC and we have to be very accurate with our updates.
1228 */
1229#define XFS_FDBLOCKS_BATCH 1024
1230int
1231xfs_mod_fdblocks(
1232 struct xfs_mount *mp,
1233 int64_t delta,
1234 bool rsvd)
1235{
1236 int64_t lcounter;
1237 long long res_used;
1238 s32 batch;
1239
1240 if (delta > 0) {
1241 /*
1242 * If the reserve pool is depleted, put blocks back into it
1243 * first. Most of the time the pool is full.
1244 */
1245 if (likely(mp->m_resblks == mp->m_resblks_avail)) {
1246 percpu_counter_add(&mp->m_fdblocks, delta);
1247 return 0;
1248 }
1249
1250 spin_lock(&mp->m_sb_lock);
1251 res_used = (long long)(mp->m_resblks - mp->m_resblks_avail);
1252
1253 if (res_used > delta) {
1254 mp->m_resblks_avail += delta;
1255 } else {
1256 delta -= res_used;
1257 mp->m_resblks_avail = mp->m_resblks;
1258 percpu_counter_add(&mp->m_fdblocks, delta);
1259 }
1260 spin_unlock(&mp->m_sb_lock);
1261 return 0;
1262 }
1263
1264 /*
1265 * Taking blocks away, need to be more accurate the closer we
1266 * are to zero.
1267 *
1268 * If the counter has a value of less than 2 * max batch size,
1269 * then make everything serialise as we are real close to
1270 * ENOSPC.
1271 */
1272 if (__percpu_counter_compare(&mp->m_fdblocks, 2 * XFS_FDBLOCKS_BATCH,
1273 XFS_FDBLOCKS_BATCH) < 0)
1274 batch = 1;
1275 else
1276 batch = XFS_FDBLOCKS_BATCH;
1277
1278 __percpu_counter_add(&mp->m_fdblocks, delta, batch);
1279 if (__percpu_counter_compare(&mp->m_fdblocks, mp->m_alloc_set_aside,
1280 XFS_FDBLOCKS_BATCH) >= 0) {
1281 /* we had space! */
1282 return 0;
1283 }
1284
1285 /*
1286 * lock up the sb for dipping into reserves before releasing the space
1287 * that took us to ENOSPC.
1288 */
1289 spin_lock(&mp->m_sb_lock);
1290 percpu_counter_add(&mp->m_fdblocks, -delta);
1291 if (!rsvd)
1292 goto fdblocks_enospc;
1293
1294 lcounter = (long long)mp->m_resblks_avail + delta;
1295 if (lcounter >= 0) {
1296 mp->m_resblks_avail = lcounter;
1297 spin_unlock(&mp->m_sb_lock);
1298 return 0;
1299 }
1300 printk_once(KERN_WARNING
1301 "Filesystem \"%s\": reserve blocks depleted! "
1302 "Consider increasing reserve pool size.",
1303 mp->m_fsname);
1304fdblocks_enospc:
1305 spin_unlock(&mp->m_sb_lock);
1306 return -ENOSPC;
1307}
1308
1309int
1310xfs_mod_frextents(
1311 struct xfs_mount *mp,
1312 int64_t delta)
1313{
1314 int64_t lcounter;
1315 int ret = 0;
1316
1317 spin_lock(&mp->m_sb_lock);
1318 lcounter = mp->m_sb.sb_frextents + delta;
1319 if (lcounter < 0)
1320 ret = -ENOSPC;
1321 else
1322 mp->m_sb.sb_frextents = lcounter;
1323 spin_unlock(&mp->m_sb_lock);
1324 return ret;
1325}
1326
1327/*
1328 * xfs_getsb() is called to obtain the buffer for the superblock.
1329 * The buffer is returned locked and read in from disk.
1330 * The buffer should be released with a call to xfs_brelse().
1331 *
1332 * If the flags parameter is BUF_TRYLOCK, then we'll only return
1333 * the superblock buffer if it can be locked without sleeping.
1334 * If it can't then we'll return NULL.
1335 */
1336struct xfs_buf *
1337xfs_getsb(
1338 struct xfs_mount *mp,
1339 int flags)
1340{
1341 struct xfs_buf *bp = mp->m_sb_bp;
1342
1343 if (!xfs_buf_trylock(bp)) {
1344 if (flags & XBF_TRYLOCK)
1345 return NULL;
1346 xfs_buf_lock(bp);
1347 }
1348
1349 xfs_buf_hold(bp);
1350 ASSERT(bp->b_flags & XBF_DONE);
1351 return bp;
1352}
1353
1354/*
1355 * Used to free the superblock along various error paths.
1356 */
1357void
1358xfs_freesb(
1359 struct xfs_mount *mp)
1360{
1361 struct xfs_buf *bp = mp->m_sb_bp;
1362
1363 xfs_buf_lock(bp);
1364 mp->m_sb_bp = NULL;
1365 xfs_buf_relse(bp);
1366}
1367
1368/*
1369 * If the underlying (data/log/rt) device is readonly, there are some
1370 * operations that cannot proceed.
1371 */
1372int
1373xfs_dev_is_read_only(
1374 struct xfs_mount *mp,
1375 char *message)
1376{
1377 if (xfs_readonly_buftarg(mp->m_ddev_targp) ||
1378 xfs_readonly_buftarg(mp->m_logdev_targp) ||
1379 (mp->m_rtdev_targp && xfs_readonly_buftarg(mp->m_rtdev_targp))) {
1380 xfs_notice(mp, "%s required on read-only device.", message);
1381 xfs_notice(mp, "write access unavailable, cannot proceed.");
1382 return -EROFS;
1383 }
1384 return 0;
1385}
1/*
2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18#include "xfs.h"
19#include "xfs_fs.h"
20#include "xfs_shared.h"
21#include "xfs_format.h"
22#include "xfs_log_format.h"
23#include "xfs_trans_resv.h"
24#include "xfs_bit.h"
25#include "xfs_inum.h"
26#include "xfs_sb.h"
27#include "xfs_ag.h"
28#include "xfs_mount.h"
29#include "xfs_da_format.h"
30#include "xfs_inode.h"
31#include "xfs_dir2.h"
32#include "xfs_ialloc.h"
33#include "xfs_alloc.h"
34#include "xfs_rtalloc.h"
35#include "xfs_bmap.h"
36#include "xfs_trans.h"
37#include "xfs_trans_priv.h"
38#include "xfs_log.h"
39#include "xfs_error.h"
40#include "xfs_quota.h"
41#include "xfs_fsops.h"
42#include "xfs_trace.h"
43#include "xfs_icache.h"
44#include "xfs_dinode.h"
45
46
47#ifdef HAVE_PERCPU_SB
48STATIC void xfs_icsb_balance_counter(xfs_mount_t *, xfs_sb_field_t,
49 int);
50STATIC void xfs_icsb_balance_counter_locked(xfs_mount_t *, xfs_sb_field_t,
51 int);
52STATIC void xfs_icsb_disable_counter(xfs_mount_t *, xfs_sb_field_t);
53#else
54
55#define xfs_icsb_balance_counter(mp, a, b) do { } while (0)
56#define xfs_icsb_balance_counter_locked(mp, a, b) do { } while (0)
57#endif
58
59static DEFINE_MUTEX(xfs_uuid_table_mutex);
60static int xfs_uuid_table_size;
61static uuid_t *xfs_uuid_table;
62
63/*
64 * See if the UUID is unique among mounted XFS filesystems.
65 * Mount fails if UUID is nil or a FS with the same UUID is already mounted.
66 */
67STATIC int
68xfs_uuid_mount(
69 struct xfs_mount *mp)
70{
71 uuid_t *uuid = &mp->m_sb.sb_uuid;
72 int hole, i;
73
74 if (mp->m_flags & XFS_MOUNT_NOUUID)
75 return 0;
76
77 if (uuid_is_nil(uuid)) {
78 xfs_warn(mp, "Filesystem has nil UUID - can't mount");
79 return XFS_ERROR(EINVAL);
80 }
81
82 mutex_lock(&xfs_uuid_table_mutex);
83 for (i = 0, hole = -1; i < xfs_uuid_table_size; i++) {
84 if (uuid_is_nil(&xfs_uuid_table[i])) {
85 hole = i;
86 continue;
87 }
88 if (uuid_equal(uuid, &xfs_uuid_table[i]))
89 goto out_duplicate;
90 }
91
92 if (hole < 0) {
93 xfs_uuid_table = kmem_realloc(xfs_uuid_table,
94 (xfs_uuid_table_size + 1) * sizeof(*xfs_uuid_table),
95 xfs_uuid_table_size * sizeof(*xfs_uuid_table),
96 KM_SLEEP);
97 hole = xfs_uuid_table_size++;
98 }
99 xfs_uuid_table[hole] = *uuid;
100 mutex_unlock(&xfs_uuid_table_mutex);
101
102 return 0;
103
104 out_duplicate:
105 mutex_unlock(&xfs_uuid_table_mutex);
106 xfs_warn(mp, "Filesystem has duplicate UUID %pU - can't mount", uuid);
107 return XFS_ERROR(EINVAL);
108}
109
110STATIC void
111xfs_uuid_unmount(
112 struct xfs_mount *mp)
113{
114 uuid_t *uuid = &mp->m_sb.sb_uuid;
115 int i;
116
117 if (mp->m_flags & XFS_MOUNT_NOUUID)
118 return;
119
120 mutex_lock(&xfs_uuid_table_mutex);
121 for (i = 0; i < xfs_uuid_table_size; i++) {
122 if (uuid_is_nil(&xfs_uuid_table[i]))
123 continue;
124 if (!uuid_equal(uuid, &xfs_uuid_table[i]))
125 continue;
126 memset(&xfs_uuid_table[i], 0, sizeof(uuid_t));
127 break;
128 }
129 ASSERT(i < xfs_uuid_table_size);
130 mutex_unlock(&xfs_uuid_table_mutex);
131}
132
133
134STATIC void
135__xfs_free_perag(
136 struct rcu_head *head)
137{
138 struct xfs_perag *pag = container_of(head, struct xfs_perag, rcu_head);
139
140 ASSERT(atomic_read(&pag->pag_ref) == 0);
141 kmem_free(pag);
142}
143
144/*
145 * Free up the per-ag resources associated with the mount structure.
146 */
147STATIC void
148xfs_free_perag(
149 xfs_mount_t *mp)
150{
151 xfs_agnumber_t agno;
152 struct xfs_perag *pag;
153
154 for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
155 spin_lock(&mp->m_perag_lock);
156 pag = radix_tree_delete(&mp->m_perag_tree, agno);
157 spin_unlock(&mp->m_perag_lock);
158 ASSERT(pag);
159 ASSERT(atomic_read(&pag->pag_ref) == 0);
160 call_rcu(&pag->rcu_head, __xfs_free_perag);
161 }
162}
163
164/*
165 * Check size of device based on the (data/realtime) block count.
166 * Note: this check is used by the growfs code as well as mount.
167 */
168int
169xfs_sb_validate_fsb_count(
170 xfs_sb_t *sbp,
171 __uint64_t nblocks)
172{
173 ASSERT(PAGE_SHIFT >= sbp->sb_blocklog);
174 ASSERT(sbp->sb_blocklog >= BBSHIFT);
175
176#if XFS_BIG_BLKNOS /* Limited by ULONG_MAX of page cache index */
177 if (nblocks >> (PAGE_CACHE_SHIFT - sbp->sb_blocklog) > ULONG_MAX)
178 return EFBIG;
179#else /* Limited by UINT_MAX of sectors */
180 if (nblocks << (sbp->sb_blocklog - BBSHIFT) > UINT_MAX)
181 return EFBIG;
182#endif
183 return 0;
184}
185
186int
187xfs_initialize_perag(
188 xfs_mount_t *mp,
189 xfs_agnumber_t agcount,
190 xfs_agnumber_t *maxagi)
191{
192 xfs_agnumber_t index;
193 xfs_agnumber_t first_initialised = 0;
194 xfs_perag_t *pag;
195 xfs_agino_t agino;
196 xfs_ino_t ino;
197 xfs_sb_t *sbp = &mp->m_sb;
198 int error = -ENOMEM;
199
200 /*
201 * Walk the current per-ag tree so we don't try to initialise AGs
202 * that already exist (growfs case). Allocate and insert all the
203 * AGs we don't find ready for initialisation.
204 */
205 for (index = 0; index < agcount; index++) {
206 pag = xfs_perag_get(mp, index);
207 if (pag) {
208 xfs_perag_put(pag);
209 continue;
210 }
211 if (!first_initialised)
212 first_initialised = index;
213
214 pag = kmem_zalloc(sizeof(*pag), KM_MAYFAIL);
215 if (!pag)
216 goto out_unwind;
217 pag->pag_agno = index;
218 pag->pag_mount = mp;
219 spin_lock_init(&pag->pag_ici_lock);
220 mutex_init(&pag->pag_ici_reclaim_lock);
221 INIT_RADIX_TREE(&pag->pag_ici_root, GFP_ATOMIC);
222 spin_lock_init(&pag->pag_buf_lock);
223 pag->pag_buf_tree = RB_ROOT;
224
225 if (radix_tree_preload(GFP_NOFS))
226 goto out_unwind;
227
228 spin_lock(&mp->m_perag_lock);
229 if (radix_tree_insert(&mp->m_perag_tree, index, pag)) {
230 BUG();
231 spin_unlock(&mp->m_perag_lock);
232 radix_tree_preload_end();
233 error = -EEXIST;
234 goto out_unwind;
235 }
236 spin_unlock(&mp->m_perag_lock);
237 radix_tree_preload_end();
238 }
239
240 /*
241 * If we mount with the inode64 option, or no inode overflows
242 * the legacy 32-bit address space clear the inode32 option.
243 */
244 agino = XFS_OFFBNO_TO_AGINO(mp, sbp->sb_agblocks - 1, 0);
245 ino = XFS_AGINO_TO_INO(mp, agcount - 1, agino);
246
247 if ((mp->m_flags & XFS_MOUNT_SMALL_INUMS) && ino > XFS_MAXINUMBER_32)
248 mp->m_flags |= XFS_MOUNT_32BITINODES;
249 else
250 mp->m_flags &= ~XFS_MOUNT_32BITINODES;
251
252 if (mp->m_flags & XFS_MOUNT_32BITINODES)
253 index = xfs_set_inode32(mp);
254 else
255 index = xfs_set_inode64(mp);
256
257 if (maxagi)
258 *maxagi = index;
259 return 0;
260
261out_unwind:
262 kmem_free(pag);
263 for (; index > first_initialised; index--) {
264 pag = radix_tree_delete(&mp->m_perag_tree, index);
265 kmem_free(pag);
266 }
267 return error;
268}
269
270/*
271 * xfs_readsb
272 *
273 * Does the initial read of the superblock.
274 */
275int
276xfs_readsb(
277 struct xfs_mount *mp,
278 int flags)
279{
280 unsigned int sector_size;
281 struct xfs_buf *bp;
282 struct xfs_sb *sbp = &mp->m_sb;
283 int error;
284 int loud = !(flags & XFS_MFSI_QUIET);
285 const struct xfs_buf_ops *buf_ops;
286
287 ASSERT(mp->m_sb_bp == NULL);
288 ASSERT(mp->m_ddev_targp != NULL);
289
290 /*
291 * For the initial read, we must guess at the sector
292 * size based on the block device. It's enough to
293 * get the sb_sectsize out of the superblock and
294 * then reread with the proper length.
295 * We don't verify it yet, because it may not be complete.
296 */
297 sector_size = xfs_getsize_buftarg(mp->m_ddev_targp);
298 buf_ops = NULL;
299
300 /*
301 * Allocate a (locked) buffer to hold the superblock.
302 * This will be kept around at all times to optimize
303 * access to the superblock.
304 */
305reread:
306 bp = xfs_buf_read_uncached(mp->m_ddev_targp, XFS_SB_DADDR,
307 BTOBB(sector_size), 0, buf_ops);
308 if (!bp) {
309 if (loud)
310 xfs_warn(mp, "SB buffer read failed");
311 return EIO;
312 }
313 if (bp->b_error) {
314 error = bp->b_error;
315 if (loud)
316 xfs_warn(mp, "SB validate failed with error %d.", error);
317 /* bad CRC means corrupted metadata */
318 if (error == EFSBADCRC)
319 error = EFSCORRUPTED;
320 goto release_buf;
321 }
322
323 /*
324 * Initialize the mount structure from the superblock.
325 */
326 xfs_sb_from_disk(&mp->m_sb, XFS_BUF_TO_SBP(bp));
327 xfs_sb_quota_from_disk(&mp->m_sb);
328
329 /*
330 * We must be able to do sector-sized and sector-aligned IO.
331 */
332 if (sector_size > sbp->sb_sectsize) {
333 if (loud)
334 xfs_warn(mp, "device supports %u byte sectors (not %u)",
335 sector_size, sbp->sb_sectsize);
336 error = ENOSYS;
337 goto release_buf;
338 }
339
340 /*
341 * Re-read the superblock so the buffer is correctly sized,
342 * and properly verified.
343 */
344 if (buf_ops == NULL) {
345 xfs_buf_relse(bp);
346 sector_size = sbp->sb_sectsize;
347 buf_ops = loud ? &xfs_sb_buf_ops : &xfs_sb_quiet_buf_ops;
348 goto reread;
349 }
350
351 /* Initialize per-cpu counters */
352 xfs_icsb_reinit_counters(mp);
353
354 /* no need to be quiet anymore, so reset the buf ops */
355 bp->b_ops = &xfs_sb_buf_ops;
356
357 mp->m_sb_bp = bp;
358 xfs_buf_unlock(bp);
359 return 0;
360
361release_buf:
362 xfs_buf_relse(bp);
363 return error;
364}
365
366/*
367 * Update alignment values based on mount options and sb values
368 */
369STATIC int
370xfs_update_alignment(xfs_mount_t *mp)
371{
372 xfs_sb_t *sbp = &(mp->m_sb);
373
374 if (mp->m_dalign) {
375 /*
376 * If stripe unit and stripe width are not multiples
377 * of the fs blocksize turn off alignment.
378 */
379 if ((BBTOB(mp->m_dalign) & mp->m_blockmask) ||
380 (BBTOB(mp->m_swidth) & mp->m_blockmask)) {
381 xfs_warn(mp,
382 "alignment check failed: sunit/swidth vs. blocksize(%d)",
383 sbp->sb_blocksize);
384 return XFS_ERROR(EINVAL);
385 } else {
386 /*
387 * Convert the stripe unit and width to FSBs.
388 */
389 mp->m_dalign = XFS_BB_TO_FSBT(mp, mp->m_dalign);
390 if (mp->m_dalign && (sbp->sb_agblocks % mp->m_dalign)) {
391 xfs_warn(mp,
392 "alignment check failed: sunit/swidth vs. agsize(%d)",
393 sbp->sb_agblocks);
394 return XFS_ERROR(EINVAL);
395 } else if (mp->m_dalign) {
396 mp->m_swidth = XFS_BB_TO_FSBT(mp, mp->m_swidth);
397 } else {
398 xfs_warn(mp,
399 "alignment check failed: sunit(%d) less than bsize(%d)",
400 mp->m_dalign, sbp->sb_blocksize);
401 return XFS_ERROR(EINVAL);
402 }
403 }
404
405 /*
406 * Update superblock with new values
407 * and log changes
408 */
409 if (xfs_sb_version_hasdalign(sbp)) {
410 if (sbp->sb_unit != mp->m_dalign) {
411 sbp->sb_unit = mp->m_dalign;
412 mp->m_update_flags |= XFS_SB_UNIT;
413 }
414 if (sbp->sb_width != mp->m_swidth) {
415 sbp->sb_width = mp->m_swidth;
416 mp->m_update_flags |= XFS_SB_WIDTH;
417 }
418 } else {
419 xfs_warn(mp,
420 "cannot change alignment: superblock does not support data alignment");
421 return XFS_ERROR(EINVAL);
422 }
423 } else if ((mp->m_flags & XFS_MOUNT_NOALIGN) != XFS_MOUNT_NOALIGN &&
424 xfs_sb_version_hasdalign(&mp->m_sb)) {
425 mp->m_dalign = sbp->sb_unit;
426 mp->m_swidth = sbp->sb_width;
427 }
428
429 return 0;
430}
431
432/*
433 * Set the maximum inode count for this filesystem
434 */
435STATIC void
436xfs_set_maxicount(xfs_mount_t *mp)
437{
438 xfs_sb_t *sbp = &(mp->m_sb);
439 __uint64_t icount;
440
441 if (sbp->sb_imax_pct) {
442 /*
443 * Make sure the maximum inode count is a multiple
444 * of the units we allocate inodes in.
445 */
446 icount = sbp->sb_dblocks * sbp->sb_imax_pct;
447 do_div(icount, 100);
448 do_div(icount, mp->m_ialloc_blks);
449 mp->m_maxicount = (icount * mp->m_ialloc_blks) <<
450 sbp->sb_inopblog;
451 } else {
452 mp->m_maxicount = 0;
453 }
454}
455
456/*
457 * Set the default minimum read and write sizes unless
458 * already specified in a mount option.
459 * We use smaller I/O sizes when the file system
460 * is being used for NFS service (wsync mount option).
461 */
462STATIC void
463xfs_set_rw_sizes(xfs_mount_t *mp)
464{
465 xfs_sb_t *sbp = &(mp->m_sb);
466 int readio_log, writeio_log;
467
468 if (!(mp->m_flags & XFS_MOUNT_DFLT_IOSIZE)) {
469 if (mp->m_flags & XFS_MOUNT_WSYNC) {
470 readio_log = XFS_WSYNC_READIO_LOG;
471 writeio_log = XFS_WSYNC_WRITEIO_LOG;
472 } else {
473 readio_log = XFS_READIO_LOG_LARGE;
474 writeio_log = XFS_WRITEIO_LOG_LARGE;
475 }
476 } else {
477 readio_log = mp->m_readio_log;
478 writeio_log = mp->m_writeio_log;
479 }
480
481 if (sbp->sb_blocklog > readio_log) {
482 mp->m_readio_log = sbp->sb_blocklog;
483 } else {
484 mp->m_readio_log = readio_log;
485 }
486 mp->m_readio_blocks = 1 << (mp->m_readio_log - sbp->sb_blocklog);
487 if (sbp->sb_blocklog > writeio_log) {
488 mp->m_writeio_log = sbp->sb_blocklog;
489 } else {
490 mp->m_writeio_log = writeio_log;
491 }
492 mp->m_writeio_blocks = 1 << (mp->m_writeio_log - sbp->sb_blocklog);
493}
494
495/*
496 * precalculate the low space thresholds for dynamic speculative preallocation.
497 */
498void
499xfs_set_low_space_thresholds(
500 struct xfs_mount *mp)
501{
502 int i;
503
504 for (i = 0; i < XFS_LOWSP_MAX; i++) {
505 __uint64_t space = mp->m_sb.sb_dblocks;
506
507 do_div(space, 100);
508 mp->m_low_space[i] = space * (i + 1);
509 }
510}
511
512
513/*
514 * Set whether we're using inode alignment.
515 */
516STATIC void
517xfs_set_inoalignment(xfs_mount_t *mp)
518{
519 if (xfs_sb_version_hasalign(&mp->m_sb) &&
520 mp->m_sb.sb_inoalignmt >=
521 XFS_B_TO_FSBT(mp, mp->m_inode_cluster_size))
522 mp->m_inoalign_mask = mp->m_sb.sb_inoalignmt - 1;
523 else
524 mp->m_inoalign_mask = 0;
525 /*
526 * If we are using stripe alignment, check whether
527 * the stripe unit is a multiple of the inode alignment
528 */
529 if (mp->m_dalign && mp->m_inoalign_mask &&
530 !(mp->m_dalign & mp->m_inoalign_mask))
531 mp->m_sinoalign = mp->m_dalign;
532 else
533 mp->m_sinoalign = 0;
534}
535
536/*
537 * Check that the data (and log if separate) is an ok size.
538 */
539STATIC int
540xfs_check_sizes(xfs_mount_t *mp)
541{
542 xfs_buf_t *bp;
543 xfs_daddr_t d;
544
545 d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks);
546 if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_dblocks) {
547 xfs_warn(mp, "filesystem size mismatch detected");
548 return XFS_ERROR(EFBIG);
549 }
550 bp = xfs_buf_read_uncached(mp->m_ddev_targp,
551 d - XFS_FSS_TO_BB(mp, 1),
552 XFS_FSS_TO_BB(mp, 1), 0, NULL);
553 if (!bp) {
554 xfs_warn(mp, "last sector read failed");
555 return EIO;
556 }
557 xfs_buf_relse(bp);
558
559 if (mp->m_logdev_targp != mp->m_ddev_targp) {
560 d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_logblocks);
561 if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_logblocks) {
562 xfs_warn(mp, "log size mismatch detected");
563 return XFS_ERROR(EFBIG);
564 }
565 bp = xfs_buf_read_uncached(mp->m_logdev_targp,
566 d - XFS_FSB_TO_BB(mp, 1),
567 XFS_FSB_TO_BB(mp, 1), 0, NULL);
568 if (!bp) {
569 xfs_warn(mp, "log device read failed");
570 return EIO;
571 }
572 xfs_buf_relse(bp);
573 }
574 return 0;
575}
576
577/*
578 * Clear the quotaflags in memory and in the superblock.
579 */
580int
581xfs_mount_reset_sbqflags(
582 struct xfs_mount *mp)
583{
584 int error;
585 struct xfs_trans *tp;
586
587 mp->m_qflags = 0;
588
589 /*
590 * It is OK to look at sb_qflags here in mount path,
591 * without m_sb_lock.
592 */
593 if (mp->m_sb.sb_qflags == 0)
594 return 0;
595 spin_lock(&mp->m_sb_lock);
596 mp->m_sb.sb_qflags = 0;
597 spin_unlock(&mp->m_sb_lock);
598
599 /*
600 * If the fs is readonly, let the incore superblock run
601 * with quotas off but don't flush the update out to disk
602 */
603 if (mp->m_flags & XFS_MOUNT_RDONLY)
604 return 0;
605
606 tp = xfs_trans_alloc(mp, XFS_TRANS_QM_SBCHANGE);
607 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_qm_sbchange, 0, 0);
608 if (error) {
609 xfs_trans_cancel(tp, 0);
610 xfs_alert(mp, "%s: Superblock update failed!", __func__);
611 return error;
612 }
613
614 xfs_mod_sb(tp, XFS_SB_QFLAGS);
615 return xfs_trans_commit(tp, 0);
616}
617
618__uint64_t
619xfs_default_resblks(xfs_mount_t *mp)
620{
621 __uint64_t resblks;
622
623 /*
624 * We default to 5% or 8192 fsbs of space reserved, whichever is
625 * smaller. This is intended to cover concurrent allocation
626 * transactions when we initially hit enospc. These each require a 4
627 * block reservation. Hence by default we cover roughly 2000 concurrent
628 * allocation reservations.
629 */
630 resblks = mp->m_sb.sb_dblocks;
631 do_div(resblks, 20);
632 resblks = min_t(__uint64_t, resblks, 8192);
633 return resblks;
634}
635
636/*
637 * This function does the following on an initial mount of a file system:
638 * - reads the superblock from disk and init the mount struct
639 * - if we're a 32-bit kernel, do a size check on the superblock
640 * so we don't mount terabyte filesystems
641 * - init mount struct realtime fields
642 * - allocate inode hash table for fs
643 * - init directory manager
644 * - perform recovery and init the log manager
645 */
646int
647xfs_mountfs(
648 xfs_mount_t *mp)
649{
650 xfs_sb_t *sbp = &(mp->m_sb);
651 xfs_inode_t *rip;
652 __uint64_t resblks;
653 uint quotamount = 0;
654 uint quotaflags = 0;
655 int error = 0;
656
657 xfs_sb_mount_common(mp, sbp);
658
659 /*
660 * Check for a mismatched features2 values. Older kernels
661 * read & wrote into the wrong sb offset for sb_features2
662 * on some platforms due to xfs_sb_t not being 64bit size aligned
663 * when sb_features2 was added, which made older superblock
664 * reading/writing routines swap it as a 64-bit value.
665 *
666 * For backwards compatibility, we make both slots equal.
667 *
668 * If we detect a mismatched field, we OR the set bits into the
669 * existing features2 field in case it has already been modified; we
670 * don't want to lose any features. We then update the bad location
671 * with the ORed value so that older kernels will see any features2
672 * flags, and mark the two fields as needing updates once the
673 * transaction subsystem is online.
674 */
675 if (xfs_sb_has_mismatched_features2(sbp)) {
676 xfs_warn(mp, "correcting sb_features alignment problem");
677 sbp->sb_features2 |= sbp->sb_bad_features2;
678 sbp->sb_bad_features2 = sbp->sb_features2;
679 mp->m_update_flags |= XFS_SB_FEATURES2 | XFS_SB_BAD_FEATURES2;
680
681 /*
682 * Re-check for ATTR2 in case it was found in bad_features2
683 * slot.
684 */
685 if (xfs_sb_version_hasattr2(&mp->m_sb) &&
686 !(mp->m_flags & XFS_MOUNT_NOATTR2))
687 mp->m_flags |= XFS_MOUNT_ATTR2;
688 }
689
690 if (xfs_sb_version_hasattr2(&mp->m_sb) &&
691 (mp->m_flags & XFS_MOUNT_NOATTR2)) {
692 xfs_sb_version_removeattr2(&mp->m_sb);
693 mp->m_update_flags |= XFS_SB_FEATURES2;
694
695 /* update sb_versionnum for the clearing of the morebits */
696 if (!sbp->sb_features2)
697 mp->m_update_flags |= XFS_SB_VERSIONNUM;
698 }
699
700 /*
701 * Check if sb_agblocks is aligned at stripe boundary
702 * If sb_agblocks is NOT aligned turn off m_dalign since
703 * allocator alignment is within an ag, therefore ag has
704 * to be aligned at stripe boundary.
705 */
706 error = xfs_update_alignment(mp);
707 if (error)
708 goto out;
709
710 xfs_alloc_compute_maxlevels(mp);
711 xfs_bmap_compute_maxlevels(mp, XFS_DATA_FORK);
712 xfs_bmap_compute_maxlevels(mp, XFS_ATTR_FORK);
713 xfs_ialloc_compute_maxlevels(mp);
714
715 xfs_set_maxicount(mp);
716
717 error = xfs_uuid_mount(mp);
718 if (error)
719 goto out;
720
721 /*
722 * Set the minimum read and write sizes
723 */
724 xfs_set_rw_sizes(mp);
725
726 /* set the low space thresholds for dynamic preallocation */
727 xfs_set_low_space_thresholds(mp);
728
729 /*
730 * Set the inode cluster size.
731 * This may still be overridden by the file system
732 * block size if it is larger than the chosen cluster size.
733 *
734 * For v5 filesystems, scale the cluster size with the inode size to
735 * keep a constant ratio of inode per cluster buffer, but only if mkfs
736 * has set the inode alignment value appropriately for larger cluster
737 * sizes.
738 */
739 mp->m_inode_cluster_size = XFS_INODE_BIG_CLUSTER_SIZE;
740 if (xfs_sb_version_hascrc(&mp->m_sb)) {
741 int new_size = mp->m_inode_cluster_size;
742
743 new_size *= mp->m_sb.sb_inodesize / XFS_DINODE_MIN_SIZE;
744 if (mp->m_sb.sb_inoalignmt >= XFS_B_TO_FSBT(mp, new_size))
745 mp->m_inode_cluster_size = new_size;
746 }
747
748 /*
749 * Set inode alignment fields
750 */
751 xfs_set_inoalignment(mp);
752
753 /*
754 * Check that the data (and log if separate) is an ok size.
755 */
756 error = xfs_check_sizes(mp);
757 if (error)
758 goto out_remove_uuid;
759
760 /*
761 * Initialize realtime fields in the mount structure
762 */
763 error = xfs_rtmount_init(mp);
764 if (error) {
765 xfs_warn(mp, "RT mount failed");
766 goto out_remove_uuid;
767 }
768
769 /*
770 * Copies the low order bits of the timestamp and the randomly
771 * set "sequence" number out of a UUID.
772 */
773 uuid_getnodeuniq(&sbp->sb_uuid, mp->m_fixedfsid);
774
775 mp->m_dmevmask = 0; /* not persistent; set after each mount */
776
777 xfs_dir_mount(mp);
778
779 /*
780 * Initialize the attribute manager's entries.
781 */
782 mp->m_attr_magicpct = (mp->m_sb.sb_blocksize * 37) / 100;
783
784 /*
785 * Initialize the precomputed transaction reservations values.
786 */
787 xfs_trans_init(mp);
788
789 /*
790 * Allocate and initialize the per-ag data.
791 */
792 spin_lock_init(&mp->m_perag_lock);
793 INIT_RADIX_TREE(&mp->m_perag_tree, GFP_ATOMIC);
794 error = xfs_initialize_perag(mp, sbp->sb_agcount, &mp->m_maxagi);
795 if (error) {
796 xfs_warn(mp, "Failed per-ag init: %d", error);
797 goto out_remove_uuid;
798 }
799
800 if (!sbp->sb_logblocks) {
801 xfs_warn(mp, "no log defined");
802 XFS_ERROR_REPORT("xfs_mountfs", XFS_ERRLEVEL_LOW, mp);
803 error = XFS_ERROR(EFSCORRUPTED);
804 goto out_free_perag;
805 }
806
807 /*
808 * log's mount-time initialization. Perform 1st part recovery if needed
809 */
810 error = xfs_log_mount(mp, mp->m_logdev_targp,
811 XFS_FSB_TO_DADDR(mp, sbp->sb_logstart),
812 XFS_FSB_TO_BB(mp, sbp->sb_logblocks));
813 if (error) {
814 xfs_warn(mp, "log mount failed");
815 goto out_fail_wait;
816 }
817
818 /*
819 * Now the log is mounted, we know if it was an unclean shutdown or
820 * not. If it was, with the first phase of recovery has completed, we
821 * have consistent AG blocks on disk. We have not recovered EFIs yet,
822 * but they are recovered transactionally in the second recovery phase
823 * later.
824 *
825 * Hence we can safely re-initialise incore superblock counters from
826 * the per-ag data. These may not be correct if the filesystem was not
827 * cleanly unmounted, so we need to wait for recovery to finish before
828 * doing this.
829 *
830 * If the filesystem was cleanly unmounted, then we can trust the
831 * values in the superblock to be correct and we don't need to do
832 * anything here.
833 *
834 * If we are currently making the filesystem, the initialisation will
835 * fail as the perag data is in an undefined state.
836 */
837 if (xfs_sb_version_haslazysbcount(&mp->m_sb) &&
838 !XFS_LAST_UNMOUNT_WAS_CLEAN(mp) &&
839 !mp->m_sb.sb_inprogress) {
840 error = xfs_initialize_perag_data(mp, sbp->sb_agcount);
841 if (error)
842 goto out_fail_wait;
843 }
844
845 /*
846 * Get and sanity-check the root inode.
847 * Save the pointer to it in the mount structure.
848 */
849 error = xfs_iget(mp, NULL, sbp->sb_rootino, 0, XFS_ILOCK_EXCL, &rip);
850 if (error) {
851 xfs_warn(mp, "failed to read root inode");
852 goto out_log_dealloc;
853 }
854
855 ASSERT(rip != NULL);
856
857 if (unlikely(!S_ISDIR(rip->i_d.di_mode))) {
858 xfs_warn(mp, "corrupted root inode %llu: not a directory",
859 (unsigned long long)rip->i_ino);
860 xfs_iunlock(rip, XFS_ILOCK_EXCL);
861 XFS_ERROR_REPORT("xfs_mountfs_int(2)", XFS_ERRLEVEL_LOW,
862 mp);
863 error = XFS_ERROR(EFSCORRUPTED);
864 goto out_rele_rip;
865 }
866 mp->m_rootip = rip; /* save it */
867
868 xfs_iunlock(rip, XFS_ILOCK_EXCL);
869
870 /*
871 * Initialize realtime inode pointers in the mount structure
872 */
873 error = xfs_rtmount_inodes(mp);
874 if (error) {
875 /*
876 * Free up the root inode.
877 */
878 xfs_warn(mp, "failed to read RT inodes");
879 goto out_rele_rip;
880 }
881
882 /*
883 * If this is a read-only mount defer the superblock updates until
884 * the next remount into writeable mode. Otherwise we would never
885 * perform the update e.g. for the root filesystem.
886 */
887 if (mp->m_update_flags && !(mp->m_flags & XFS_MOUNT_RDONLY)) {
888 error = xfs_mount_log_sb(mp, mp->m_update_flags);
889 if (error) {
890 xfs_warn(mp, "failed to write sb changes");
891 goto out_rtunmount;
892 }
893 }
894
895 /*
896 * Initialise the XFS quota management subsystem for this mount
897 */
898 if (XFS_IS_QUOTA_RUNNING(mp)) {
899 error = xfs_qm_newmount(mp, "amount, "aflags);
900 if (error)
901 goto out_rtunmount;
902 } else {
903 ASSERT(!XFS_IS_QUOTA_ON(mp));
904
905 /*
906 * If a file system had quotas running earlier, but decided to
907 * mount without -o uquota/pquota/gquota options, revoke the
908 * quotachecked license.
909 */
910 if (mp->m_sb.sb_qflags & XFS_ALL_QUOTA_ACCT) {
911 xfs_notice(mp, "resetting quota flags");
912 error = xfs_mount_reset_sbqflags(mp);
913 if (error)
914 return error;
915 }
916 }
917
918 /*
919 * Finish recovering the file system. This part needed to be
920 * delayed until after the root and real-time bitmap inodes
921 * were consistently read in.
922 */
923 error = xfs_log_mount_finish(mp);
924 if (error) {
925 xfs_warn(mp, "log mount finish failed");
926 goto out_rtunmount;
927 }
928
929 /*
930 * Complete the quota initialisation, post-log-replay component.
931 */
932 if (quotamount) {
933 ASSERT(mp->m_qflags == 0);
934 mp->m_qflags = quotaflags;
935
936 xfs_qm_mount_quotas(mp);
937 }
938
939 /*
940 * Now we are mounted, reserve a small amount of unused space for
941 * privileged transactions. This is needed so that transaction
942 * space required for critical operations can dip into this pool
943 * when at ENOSPC. This is needed for operations like create with
944 * attr, unwritten extent conversion at ENOSPC, etc. Data allocations
945 * are not allowed to use this reserved space.
946 *
947 * This may drive us straight to ENOSPC on mount, but that implies
948 * we were already there on the last unmount. Warn if this occurs.
949 */
950 if (!(mp->m_flags & XFS_MOUNT_RDONLY)) {
951 resblks = xfs_default_resblks(mp);
952 error = xfs_reserve_blocks(mp, &resblks, NULL);
953 if (error)
954 xfs_warn(mp,
955 "Unable to allocate reserve blocks. Continuing without reserve pool.");
956 }
957
958 return 0;
959
960 out_rtunmount:
961 xfs_rtunmount_inodes(mp);
962 out_rele_rip:
963 IRELE(rip);
964 out_log_dealloc:
965 xfs_log_unmount(mp);
966 out_fail_wait:
967 if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp)
968 xfs_wait_buftarg(mp->m_logdev_targp);
969 xfs_wait_buftarg(mp->m_ddev_targp);
970 out_free_perag:
971 xfs_free_perag(mp);
972 out_remove_uuid:
973 xfs_uuid_unmount(mp);
974 out:
975 return error;
976}
977
978/*
979 * This flushes out the inodes,dquots and the superblock, unmounts the
980 * log and makes sure that incore structures are freed.
981 */
982void
983xfs_unmountfs(
984 struct xfs_mount *mp)
985{
986 __uint64_t resblks;
987 int error;
988
989 cancel_delayed_work_sync(&mp->m_eofblocks_work);
990
991 xfs_qm_unmount_quotas(mp);
992 xfs_rtunmount_inodes(mp);
993 IRELE(mp->m_rootip);
994
995 /*
996 * We can potentially deadlock here if we have an inode cluster
997 * that has been freed has its buffer still pinned in memory because
998 * the transaction is still sitting in a iclog. The stale inodes
999 * on that buffer will have their flush locks held until the
1000 * transaction hits the disk and the callbacks run. the inode
1001 * flush takes the flush lock unconditionally and with nothing to
1002 * push out the iclog we will never get that unlocked. hence we
1003 * need to force the log first.
1004 */
1005 xfs_log_force(mp, XFS_LOG_SYNC);
1006
1007 /*
1008 * Flush all pending changes from the AIL.
1009 */
1010 xfs_ail_push_all_sync(mp->m_ail);
1011
1012 /*
1013 * And reclaim all inodes. At this point there should be no dirty
1014 * inodes and none should be pinned or locked, but use synchronous
1015 * reclaim just to be sure. We can stop background inode reclaim
1016 * here as well if it is still running.
1017 */
1018 cancel_delayed_work_sync(&mp->m_reclaim_work);
1019 xfs_reclaim_inodes(mp, SYNC_WAIT);
1020
1021 xfs_qm_unmount(mp);
1022
1023 /*
1024 * Unreserve any blocks we have so that when we unmount we don't account
1025 * the reserved free space as used. This is really only necessary for
1026 * lazy superblock counting because it trusts the incore superblock
1027 * counters to be absolutely correct on clean unmount.
1028 *
1029 * We don't bother correcting this elsewhere for lazy superblock
1030 * counting because on mount of an unclean filesystem we reconstruct the
1031 * correct counter value and this is irrelevant.
1032 *
1033 * For non-lazy counter filesystems, this doesn't matter at all because
1034 * we only every apply deltas to the superblock and hence the incore
1035 * value does not matter....
1036 */
1037 resblks = 0;
1038 error = xfs_reserve_blocks(mp, &resblks, NULL);
1039 if (error)
1040 xfs_warn(mp, "Unable to free reserved block pool. "
1041 "Freespace may not be correct on next mount.");
1042
1043 error = xfs_log_sbcount(mp);
1044 if (error)
1045 xfs_warn(mp, "Unable to update superblock counters. "
1046 "Freespace may not be correct on next mount.");
1047
1048 xfs_log_unmount(mp);
1049 xfs_uuid_unmount(mp);
1050
1051#if defined(DEBUG)
1052 xfs_errortag_clearall(mp, 0);
1053#endif
1054 xfs_free_perag(mp);
1055}
1056
1057int
1058xfs_fs_writable(xfs_mount_t *mp)
1059{
1060 return !(mp->m_super->s_writers.frozen || XFS_FORCED_SHUTDOWN(mp) ||
1061 (mp->m_flags & XFS_MOUNT_RDONLY));
1062}
1063
1064/*
1065 * xfs_log_sbcount
1066 *
1067 * Sync the superblock counters to disk.
1068 *
1069 * Note this code can be called during the process of freezing, so
1070 * we may need to use the transaction allocator which does not
1071 * block when the transaction subsystem is in its frozen state.
1072 */
1073int
1074xfs_log_sbcount(xfs_mount_t *mp)
1075{
1076 xfs_trans_t *tp;
1077 int error;
1078
1079 if (!xfs_fs_writable(mp))
1080 return 0;
1081
1082 xfs_icsb_sync_counters(mp, 0);
1083
1084 /*
1085 * we don't need to do this if we are updating the superblock
1086 * counters on every modification.
1087 */
1088 if (!xfs_sb_version_haslazysbcount(&mp->m_sb))
1089 return 0;
1090
1091 tp = _xfs_trans_alloc(mp, XFS_TRANS_SB_COUNT, KM_SLEEP);
1092 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_sb, 0, 0);
1093 if (error) {
1094 xfs_trans_cancel(tp, 0);
1095 return error;
1096 }
1097
1098 xfs_mod_sb(tp, XFS_SB_IFREE | XFS_SB_ICOUNT | XFS_SB_FDBLOCKS);
1099 xfs_trans_set_sync(tp);
1100 error = xfs_trans_commit(tp, 0);
1101 return error;
1102}
1103
1104/*
1105 * xfs_mod_incore_sb_unlocked() is a utility routine commonly used to apply
1106 * a delta to a specified field in the in-core superblock. Simply
1107 * switch on the field indicated and apply the delta to that field.
1108 * Fields are not allowed to dip below zero, so if the delta would
1109 * do this do not apply it and return EINVAL.
1110 *
1111 * The m_sb_lock must be held when this routine is called.
1112 */
1113STATIC int
1114xfs_mod_incore_sb_unlocked(
1115 xfs_mount_t *mp,
1116 xfs_sb_field_t field,
1117 int64_t delta,
1118 int rsvd)
1119{
1120 int scounter; /* short counter for 32 bit fields */
1121 long long lcounter; /* long counter for 64 bit fields */
1122 long long res_used, rem;
1123
1124 /*
1125 * With the in-core superblock spin lock held, switch
1126 * on the indicated field. Apply the delta to the
1127 * proper field. If the fields value would dip below
1128 * 0, then do not apply the delta and return EINVAL.
1129 */
1130 switch (field) {
1131 case XFS_SBS_ICOUNT:
1132 lcounter = (long long)mp->m_sb.sb_icount;
1133 lcounter += delta;
1134 if (lcounter < 0) {
1135 ASSERT(0);
1136 return XFS_ERROR(EINVAL);
1137 }
1138 mp->m_sb.sb_icount = lcounter;
1139 return 0;
1140 case XFS_SBS_IFREE:
1141 lcounter = (long long)mp->m_sb.sb_ifree;
1142 lcounter += delta;
1143 if (lcounter < 0) {
1144 ASSERT(0);
1145 return XFS_ERROR(EINVAL);
1146 }
1147 mp->m_sb.sb_ifree = lcounter;
1148 return 0;
1149 case XFS_SBS_FDBLOCKS:
1150 lcounter = (long long)
1151 mp->m_sb.sb_fdblocks - XFS_ALLOC_SET_ASIDE(mp);
1152 res_used = (long long)(mp->m_resblks - mp->m_resblks_avail);
1153
1154 if (delta > 0) { /* Putting blocks back */
1155 if (res_used > delta) {
1156 mp->m_resblks_avail += delta;
1157 } else {
1158 rem = delta - res_used;
1159 mp->m_resblks_avail = mp->m_resblks;
1160 lcounter += rem;
1161 }
1162 } else { /* Taking blocks away */
1163 lcounter += delta;
1164 if (lcounter >= 0) {
1165 mp->m_sb.sb_fdblocks = lcounter +
1166 XFS_ALLOC_SET_ASIDE(mp);
1167 return 0;
1168 }
1169
1170 /*
1171 * We are out of blocks, use any available reserved
1172 * blocks if were allowed to.
1173 */
1174 if (!rsvd)
1175 return XFS_ERROR(ENOSPC);
1176
1177 lcounter = (long long)mp->m_resblks_avail + delta;
1178 if (lcounter >= 0) {
1179 mp->m_resblks_avail = lcounter;
1180 return 0;
1181 }
1182 printk_once(KERN_WARNING
1183 "Filesystem \"%s\": reserve blocks depleted! "
1184 "Consider increasing reserve pool size.",
1185 mp->m_fsname);
1186 return XFS_ERROR(ENOSPC);
1187 }
1188
1189 mp->m_sb.sb_fdblocks = lcounter + XFS_ALLOC_SET_ASIDE(mp);
1190 return 0;
1191 case XFS_SBS_FREXTENTS:
1192 lcounter = (long long)mp->m_sb.sb_frextents;
1193 lcounter += delta;
1194 if (lcounter < 0) {
1195 return XFS_ERROR(ENOSPC);
1196 }
1197 mp->m_sb.sb_frextents = lcounter;
1198 return 0;
1199 case XFS_SBS_DBLOCKS:
1200 lcounter = (long long)mp->m_sb.sb_dblocks;
1201 lcounter += delta;
1202 if (lcounter < 0) {
1203 ASSERT(0);
1204 return XFS_ERROR(EINVAL);
1205 }
1206 mp->m_sb.sb_dblocks = lcounter;
1207 return 0;
1208 case XFS_SBS_AGCOUNT:
1209 scounter = mp->m_sb.sb_agcount;
1210 scounter += delta;
1211 if (scounter < 0) {
1212 ASSERT(0);
1213 return XFS_ERROR(EINVAL);
1214 }
1215 mp->m_sb.sb_agcount = scounter;
1216 return 0;
1217 case XFS_SBS_IMAX_PCT:
1218 scounter = mp->m_sb.sb_imax_pct;
1219 scounter += delta;
1220 if (scounter < 0) {
1221 ASSERT(0);
1222 return XFS_ERROR(EINVAL);
1223 }
1224 mp->m_sb.sb_imax_pct = scounter;
1225 return 0;
1226 case XFS_SBS_REXTSIZE:
1227 scounter = mp->m_sb.sb_rextsize;
1228 scounter += delta;
1229 if (scounter < 0) {
1230 ASSERT(0);
1231 return XFS_ERROR(EINVAL);
1232 }
1233 mp->m_sb.sb_rextsize = scounter;
1234 return 0;
1235 case XFS_SBS_RBMBLOCKS:
1236 scounter = mp->m_sb.sb_rbmblocks;
1237 scounter += delta;
1238 if (scounter < 0) {
1239 ASSERT(0);
1240 return XFS_ERROR(EINVAL);
1241 }
1242 mp->m_sb.sb_rbmblocks = scounter;
1243 return 0;
1244 case XFS_SBS_RBLOCKS:
1245 lcounter = (long long)mp->m_sb.sb_rblocks;
1246 lcounter += delta;
1247 if (lcounter < 0) {
1248 ASSERT(0);
1249 return XFS_ERROR(EINVAL);
1250 }
1251 mp->m_sb.sb_rblocks = lcounter;
1252 return 0;
1253 case XFS_SBS_REXTENTS:
1254 lcounter = (long long)mp->m_sb.sb_rextents;
1255 lcounter += delta;
1256 if (lcounter < 0) {
1257 ASSERT(0);
1258 return XFS_ERROR(EINVAL);
1259 }
1260 mp->m_sb.sb_rextents = lcounter;
1261 return 0;
1262 case XFS_SBS_REXTSLOG:
1263 scounter = mp->m_sb.sb_rextslog;
1264 scounter += delta;
1265 if (scounter < 0) {
1266 ASSERT(0);
1267 return XFS_ERROR(EINVAL);
1268 }
1269 mp->m_sb.sb_rextslog = scounter;
1270 return 0;
1271 default:
1272 ASSERT(0);
1273 return XFS_ERROR(EINVAL);
1274 }
1275}
1276
1277/*
1278 * xfs_mod_incore_sb() is used to change a field in the in-core
1279 * superblock structure by the specified delta. This modification
1280 * is protected by the m_sb_lock. Just use the xfs_mod_incore_sb_unlocked()
1281 * routine to do the work.
1282 */
1283int
1284xfs_mod_incore_sb(
1285 struct xfs_mount *mp,
1286 xfs_sb_field_t field,
1287 int64_t delta,
1288 int rsvd)
1289{
1290 int status;
1291
1292#ifdef HAVE_PERCPU_SB
1293 ASSERT(field < XFS_SBS_ICOUNT || field > XFS_SBS_FDBLOCKS);
1294#endif
1295 spin_lock(&mp->m_sb_lock);
1296 status = xfs_mod_incore_sb_unlocked(mp, field, delta, rsvd);
1297 spin_unlock(&mp->m_sb_lock);
1298
1299 return status;
1300}
1301
1302/*
1303 * Change more than one field in the in-core superblock structure at a time.
1304 *
1305 * The fields and changes to those fields are specified in the array of
1306 * xfs_mod_sb structures passed in. Either all of the specified deltas
1307 * will be applied or none of them will. If any modified field dips below 0,
1308 * then all modifications will be backed out and EINVAL will be returned.
1309 *
1310 * Note that this function may not be used for the superblock values that
1311 * are tracked with the in-memory per-cpu counters - a direct call to
1312 * xfs_icsb_modify_counters is required for these.
1313 */
1314int
1315xfs_mod_incore_sb_batch(
1316 struct xfs_mount *mp,
1317 xfs_mod_sb_t *msb,
1318 uint nmsb,
1319 int rsvd)
1320{
1321 xfs_mod_sb_t *msbp;
1322 int error = 0;
1323
1324 /*
1325 * Loop through the array of mod structures and apply each individually.
1326 * If any fail, then back out all those which have already been applied.
1327 * Do all of this within the scope of the m_sb_lock so that all of the
1328 * changes will be atomic.
1329 */
1330 spin_lock(&mp->m_sb_lock);
1331 for (msbp = msb; msbp < (msb + nmsb); msbp++) {
1332 ASSERT(msbp->msb_field < XFS_SBS_ICOUNT ||
1333 msbp->msb_field > XFS_SBS_FDBLOCKS);
1334
1335 error = xfs_mod_incore_sb_unlocked(mp, msbp->msb_field,
1336 msbp->msb_delta, rsvd);
1337 if (error)
1338 goto unwind;
1339 }
1340 spin_unlock(&mp->m_sb_lock);
1341 return 0;
1342
1343unwind:
1344 while (--msbp >= msb) {
1345 error = xfs_mod_incore_sb_unlocked(mp, msbp->msb_field,
1346 -msbp->msb_delta, rsvd);
1347 ASSERT(error == 0);
1348 }
1349 spin_unlock(&mp->m_sb_lock);
1350 return error;
1351}
1352
1353/*
1354 * xfs_getsb() is called to obtain the buffer for the superblock.
1355 * The buffer is returned locked and read in from disk.
1356 * The buffer should be released with a call to xfs_brelse().
1357 *
1358 * If the flags parameter is BUF_TRYLOCK, then we'll only return
1359 * the superblock buffer if it can be locked without sleeping.
1360 * If it can't then we'll return NULL.
1361 */
1362struct xfs_buf *
1363xfs_getsb(
1364 struct xfs_mount *mp,
1365 int flags)
1366{
1367 struct xfs_buf *bp = mp->m_sb_bp;
1368
1369 if (!xfs_buf_trylock(bp)) {
1370 if (flags & XBF_TRYLOCK)
1371 return NULL;
1372 xfs_buf_lock(bp);
1373 }
1374
1375 xfs_buf_hold(bp);
1376 ASSERT(XFS_BUF_ISDONE(bp));
1377 return bp;
1378}
1379
1380/*
1381 * Used to free the superblock along various error paths.
1382 */
1383void
1384xfs_freesb(
1385 struct xfs_mount *mp)
1386{
1387 struct xfs_buf *bp = mp->m_sb_bp;
1388
1389 xfs_buf_lock(bp);
1390 mp->m_sb_bp = NULL;
1391 xfs_buf_relse(bp);
1392}
1393
1394/*
1395 * Used to log changes to the superblock unit and width fields which could
1396 * be altered by the mount options, as well as any potential sb_features2
1397 * fixup. Only the first superblock is updated.
1398 */
1399int
1400xfs_mount_log_sb(
1401 xfs_mount_t *mp,
1402 __int64_t fields)
1403{
1404 xfs_trans_t *tp;
1405 int error;
1406
1407 ASSERT(fields & (XFS_SB_UNIT | XFS_SB_WIDTH | XFS_SB_UUID |
1408 XFS_SB_FEATURES2 | XFS_SB_BAD_FEATURES2 |
1409 XFS_SB_VERSIONNUM));
1410
1411 tp = xfs_trans_alloc(mp, XFS_TRANS_SB_UNIT);
1412 error = xfs_trans_reserve(tp, &M_RES(mp)->tr_sb, 0, 0);
1413 if (error) {
1414 xfs_trans_cancel(tp, 0);
1415 return error;
1416 }
1417 xfs_mod_sb(tp, fields);
1418 error = xfs_trans_commit(tp, 0);
1419 return error;
1420}
1421
1422/*
1423 * If the underlying (data/log/rt) device is readonly, there are some
1424 * operations that cannot proceed.
1425 */
1426int
1427xfs_dev_is_read_only(
1428 struct xfs_mount *mp,
1429 char *message)
1430{
1431 if (xfs_readonly_buftarg(mp->m_ddev_targp) ||
1432 xfs_readonly_buftarg(mp->m_logdev_targp) ||
1433 (mp->m_rtdev_targp && xfs_readonly_buftarg(mp->m_rtdev_targp))) {
1434 xfs_notice(mp, "%s required on read-only device.", message);
1435 xfs_notice(mp, "write access unavailable, cannot proceed.");
1436 return EROFS;
1437 }
1438 return 0;
1439}
1440
1441#ifdef HAVE_PERCPU_SB
1442/*
1443 * Per-cpu incore superblock counters
1444 *
1445 * Simple concept, difficult implementation
1446 *
1447 * Basically, replace the incore superblock counters with a distributed per cpu
1448 * counter for contended fields (e.g. free block count).
1449 *
1450 * Difficulties arise in that the incore sb is used for ENOSPC checking, and
1451 * hence needs to be accurately read when we are running low on space. Hence
1452 * there is a method to enable and disable the per-cpu counters based on how
1453 * much "stuff" is available in them.
1454 *
1455 * Basically, a counter is enabled if there is enough free resource to justify
1456 * running a per-cpu fast-path. If the per-cpu counter runs out (i.e. a local
1457 * ENOSPC), then we disable the counters to synchronise all callers and
1458 * re-distribute the available resources.
1459 *
1460 * If, once we redistributed the available resources, we still get a failure,
1461 * we disable the per-cpu counter and go through the slow path.
1462 *
1463 * The slow path is the current xfs_mod_incore_sb() function. This means that
1464 * when we disable a per-cpu counter, we need to drain its resources back to
1465 * the global superblock. We do this after disabling the counter to prevent
1466 * more threads from queueing up on the counter.
1467 *
1468 * Essentially, this means that we still need a lock in the fast path to enable
1469 * synchronisation between the global counters and the per-cpu counters. This
1470 * is not a problem because the lock will be local to a CPU almost all the time
1471 * and have little contention except when we get to ENOSPC conditions.
1472 *
1473 * Basically, this lock becomes a barrier that enables us to lock out the fast
1474 * path while we do things like enabling and disabling counters and
1475 * synchronising the counters.
1476 *
1477 * Locking rules:
1478 *
1479 * 1. m_sb_lock before picking up per-cpu locks
1480 * 2. per-cpu locks always picked up via for_each_online_cpu() order
1481 * 3. accurate counter sync requires m_sb_lock + per cpu locks
1482 * 4. modifying per-cpu counters requires holding per-cpu lock
1483 * 5. modifying global counters requires holding m_sb_lock
1484 * 6. enabling or disabling a counter requires holding the m_sb_lock
1485 * and _none_ of the per-cpu locks.
1486 *
1487 * Disabled counters are only ever re-enabled by a balance operation
1488 * that results in more free resources per CPU than a given threshold.
1489 * To ensure counters don't remain disabled, they are rebalanced when
1490 * the global resource goes above a higher threshold (i.e. some hysteresis
1491 * is present to prevent thrashing).
1492 */
1493
1494#ifdef CONFIG_HOTPLUG_CPU
1495/*
1496 * hot-plug CPU notifier support.
1497 *
1498 * We need a notifier per filesystem as we need to be able to identify
1499 * the filesystem to balance the counters out. This is achieved by
1500 * having a notifier block embedded in the xfs_mount_t and doing pointer
1501 * magic to get the mount pointer from the notifier block address.
1502 */
1503STATIC int
1504xfs_icsb_cpu_notify(
1505 struct notifier_block *nfb,
1506 unsigned long action,
1507 void *hcpu)
1508{
1509 xfs_icsb_cnts_t *cntp;
1510 xfs_mount_t *mp;
1511
1512 mp = (xfs_mount_t *)container_of(nfb, xfs_mount_t, m_icsb_notifier);
1513 cntp = (xfs_icsb_cnts_t *)
1514 per_cpu_ptr(mp->m_sb_cnts, (unsigned long)hcpu);
1515 switch (action) {
1516 case CPU_UP_PREPARE:
1517 case CPU_UP_PREPARE_FROZEN:
1518 /* Easy Case - initialize the area and locks, and
1519 * then rebalance when online does everything else for us. */
1520 memset(cntp, 0, sizeof(xfs_icsb_cnts_t));
1521 break;
1522 case CPU_ONLINE:
1523 case CPU_ONLINE_FROZEN:
1524 xfs_icsb_lock(mp);
1525 xfs_icsb_balance_counter(mp, XFS_SBS_ICOUNT, 0);
1526 xfs_icsb_balance_counter(mp, XFS_SBS_IFREE, 0);
1527 xfs_icsb_balance_counter(mp, XFS_SBS_FDBLOCKS, 0);
1528 xfs_icsb_unlock(mp);
1529 break;
1530 case CPU_DEAD:
1531 case CPU_DEAD_FROZEN:
1532 /* Disable all the counters, then fold the dead cpu's
1533 * count into the total on the global superblock and
1534 * re-enable the counters. */
1535 xfs_icsb_lock(mp);
1536 spin_lock(&mp->m_sb_lock);
1537 xfs_icsb_disable_counter(mp, XFS_SBS_ICOUNT);
1538 xfs_icsb_disable_counter(mp, XFS_SBS_IFREE);
1539 xfs_icsb_disable_counter(mp, XFS_SBS_FDBLOCKS);
1540
1541 mp->m_sb.sb_icount += cntp->icsb_icount;
1542 mp->m_sb.sb_ifree += cntp->icsb_ifree;
1543 mp->m_sb.sb_fdblocks += cntp->icsb_fdblocks;
1544
1545 memset(cntp, 0, sizeof(xfs_icsb_cnts_t));
1546
1547 xfs_icsb_balance_counter_locked(mp, XFS_SBS_ICOUNT, 0);
1548 xfs_icsb_balance_counter_locked(mp, XFS_SBS_IFREE, 0);
1549 xfs_icsb_balance_counter_locked(mp, XFS_SBS_FDBLOCKS, 0);
1550 spin_unlock(&mp->m_sb_lock);
1551 xfs_icsb_unlock(mp);
1552 break;
1553 }
1554
1555 return NOTIFY_OK;
1556}
1557#endif /* CONFIG_HOTPLUG_CPU */
1558
1559int
1560xfs_icsb_init_counters(
1561 xfs_mount_t *mp)
1562{
1563 xfs_icsb_cnts_t *cntp;
1564 int i;
1565
1566 mp->m_sb_cnts = alloc_percpu(xfs_icsb_cnts_t);
1567 if (mp->m_sb_cnts == NULL)
1568 return -ENOMEM;
1569
1570 for_each_online_cpu(i) {
1571 cntp = (xfs_icsb_cnts_t *)per_cpu_ptr(mp->m_sb_cnts, i);
1572 memset(cntp, 0, sizeof(xfs_icsb_cnts_t));
1573 }
1574
1575 mutex_init(&mp->m_icsb_mutex);
1576
1577 /*
1578 * start with all counters disabled so that the
1579 * initial balance kicks us off correctly
1580 */
1581 mp->m_icsb_counters = -1;
1582
1583#ifdef CONFIG_HOTPLUG_CPU
1584 mp->m_icsb_notifier.notifier_call = xfs_icsb_cpu_notify;
1585 mp->m_icsb_notifier.priority = 0;
1586 register_hotcpu_notifier(&mp->m_icsb_notifier);
1587#endif /* CONFIG_HOTPLUG_CPU */
1588
1589 return 0;
1590}
1591
1592void
1593xfs_icsb_reinit_counters(
1594 xfs_mount_t *mp)
1595{
1596 xfs_icsb_lock(mp);
1597 /*
1598 * start with all counters disabled so that the
1599 * initial balance kicks us off correctly
1600 */
1601 mp->m_icsb_counters = -1;
1602 xfs_icsb_balance_counter(mp, XFS_SBS_ICOUNT, 0);
1603 xfs_icsb_balance_counter(mp, XFS_SBS_IFREE, 0);
1604 xfs_icsb_balance_counter(mp, XFS_SBS_FDBLOCKS, 0);
1605 xfs_icsb_unlock(mp);
1606}
1607
1608void
1609xfs_icsb_destroy_counters(
1610 xfs_mount_t *mp)
1611{
1612 if (mp->m_sb_cnts) {
1613 unregister_hotcpu_notifier(&mp->m_icsb_notifier);
1614 free_percpu(mp->m_sb_cnts);
1615 }
1616 mutex_destroy(&mp->m_icsb_mutex);
1617}
1618
1619STATIC void
1620xfs_icsb_lock_cntr(
1621 xfs_icsb_cnts_t *icsbp)
1622{
1623 while (test_and_set_bit(XFS_ICSB_FLAG_LOCK, &icsbp->icsb_flags)) {
1624 ndelay(1000);
1625 }
1626}
1627
1628STATIC void
1629xfs_icsb_unlock_cntr(
1630 xfs_icsb_cnts_t *icsbp)
1631{
1632 clear_bit(XFS_ICSB_FLAG_LOCK, &icsbp->icsb_flags);
1633}
1634
1635
1636STATIC void
1637xfs_icsb_lock_all_counters(
1638 xfs_mount_t *mp)
1639{
1640 xfs_icsb_cnts_t *cntp;
1641 int i;
1642
1643 for_each_online_cpu(i) {
1644 cntp = (xfs_icsb_cnts_t *)per_cpu_ptr(mp->m_sb_cnts, i);
1645 xfs_icsb_lock_cntr(cntp);
1646 }
1647}
1648
1649STATIC void
1650xfs_icsb_unlock_all_counters(
1651 xfs_mount_t *mp)
1652{
1653 xfs_icsb_cnts_t *cntp;
1654 int i;
1655
1656 for_each_online_cpu(i) {
1657 cntp = (xfs_icsb_cnts_t *)per_cpu_ptr(mp->m_sb_cnts, i);
1658 xfs_icsb_unlock_cntr(cntp);
1659 }
1660}
1661
1662STATIC void
1663xfs_icsb_count(
1664 xfs_mount_t *mp,
1665 xfs_icsb_cnts_t *cnt,
1666 int flags)
1667{
1668 xfs_icsb_cnts_t *cntp;
1669 int i;
1670
1671 memset(cnt, 0, sizeof(xfs_icsb_cnts_t));
1672
1673 if (!(flags & XFS_ICSB_LAZY_COUNT))
1674 xfs_icsb_lock_all_counters(mp);
1675
1676 for_each_online_cpu(i) {
1677 cntp = (xfs_icsb_cnts_t *)per_cpu_ptr(mp->m_sb_cnts, i);
1678 cnt->icsb_icount += cntp->icsb_icount;
1679 cnt->icsb_ifree += cntp->icsb_ifree;
1680 cnt->icsb_fdblocks += cntp->icsb_fdblocks;
1681 }
1682
1683 if (!(flags & XFS_ICSB_LAZY_COUNT))
1684 xfs_icsb_unlock_all_counters(mp);
1685}
1686
1687STATIC int
1688xfs_icsb_counter_disabled(
1689 xfs_mount_t *mp,
1690 xfs_sb_field_t field)
1691{
1692 ASSERT((field >= XFS_SBS_ICOUNT) && (field <= XFS_SBS_FDBLOCKS));
1693 return test_bit(field, &mp->m_icsb_counters);
1694}
1695
1696STATIC void
1697xfs_icsb_disable_counter(
1698 xfs_mount_t *mp,
1699 xfs_sb_field_t field)
1700{
1701 xfs_icsb_cnts_t cnt;
1702
1703 ASSERT((field >= XFS_SBS_ICOUNT) && (field <= XFS_SBS_FDBLOCKS));
1704
1705 /*
1706 * If we are already disabled, then there is nothing to do
1707 * here. We check before locking all the counters to avoid
1708 * the expensive lock operation when being called in the
1709 * slow path and the counter is already disabled. This is
1710 * safe because the only time we set or clear this state is under
1711 * the m_icsb_mutex.
1712 */
1713 if (xfs_icsb_counter_disabled(mp, field))
1714 return;
1715
1716 xfs_icsb_lock_all_counters(mp);
1717 if (!test_and_set_bit(field, &mp->m_icsb_counters)) {
1718 /* drain back to superblock */
1719
1720 xfs_icsb_count(mp, &cnt, XFS_ICSB_LAZY_COUNT);
1721 switch(field) {
1722 case XFS_SBS_ICOUNT:
1723 mp->m_sb.sb_icount = cnt.icsb_icount;
1724 break;
1725 case XFS_SBS_IFREE:
1726 mp->m_sb.sb_ifree = cnt.icsb_ifree;
1727 break;
1728 case XFS_SBS_FDBLOCKS:
1729 mp->m_sb.sb_fdblocks = cnt.icsb_fdblocks;
1730 break;
1731 default:
1732 BUG();
1733 }
1734 }
1735
1736 xfs_icsb_unlock_all_counters(mp);
1737}
1738
1739STATIC void
1740xfs_icsb_enable_counter(
1741 xfs_mount_t *mp,
1742 xfs_sb_field_t field,
1743 uint64_t count,
1744 uint64_t resid)
1745{
1746 xfs_icsb_cnts_t *cntp;
1747 int i;
1748
1749 ASSERT((field >= XFS_SBS_ICOUNT) && (field <= XFS_SBS_FDBLOCKS));
1750
1751 xfs_icsb_lock_all_counters(mp);
1752 for_each_online_cpu(i) {
1753 cntp = per_cpu_ptr(mp->m_sb_cnts, i);
1754 switch (field) {
1755 case XFS_SBS_ICOUNT:
1756 cntp->icsb_icount = count + resid;
1757 break;
1758 case XFS_SBS_IFREE:
1759 cntp->icsb_ifree = count + resid;
1760 break;
1761 case XFS_SBS_FDBLOCKS:
1762 cntp->icsb_fdblocks = count + resid;
1763 break;
1764 default:
1765 BUG();
1766 break;
1767 }
1768 resid = 0;
1769 }
1770 clear_bit(field, &mp->m_icsb_counters);
1771 xfs_icsb_unlock_all_counters(mp);
1772}
1773
1774void
1775xfs_icsb_sync_counters_locked(
1776 xfs_mount_t *mp,
1777 int flags)
1778{
1779 xfs_icsb_cnts_t cnt;
1780
1781 xfs_icsb_count(mp, &cnt, flags);
1782
1783 if (!xfs_icsb_counter_disabled(mp, XFS_SBS_ICOUNT))
1784 mp->m_sb.sb_icount = cnt.icsb_icount;
1785 if (!xfs_icsb_counter_disabled(mp, XFS_SBS_IFREE))
1786 mp->m_sb.sb_ifree = cnt.icsb_ifree;
1787 if (!xfs_icsb_counter_disabled(mp, XFS_SBS_FDBLOCKS))
1788 mp->m_sb.sb_fdblocks = cnt.icsb_fdblocks;
1789}
1790
1791/*
1792 * Accurate update of per-cpu counters to incore superblock
1793 */
1794void
1795xfs_icsb_sync_counters(
1796 xfs_mount_t *mp,
1797 int flags)
1798{
1799 spin_lock(&mp->m_sb_lock);
1800 xfs_icsb_sync_counters_locked(mp, flags);
1801 spin_unlock(&mp->m_sb_lock);
1802}
1803
1804/*
1805 * Balance and enable/disable counters as necessary.
1806 *
1807 * Thresholds for re-enabling counters are somewhat magic. inode counts are
1808 * chosen to be the same number as single on disk allocation chunk per CPU, and
1809 * free blocks is something far enough zero that we aren't going thrash when we
1810 * get near ENOSPC. We also need to supply a minimum we require per cpu to
1811 * prevent looping endlessly when xfs_alloc_space asks for more than will
1812 * be distributed to a single CPU but each CPU has enough blocks to be
1813 * reenabled.
1814 *
1815 * Note that we can be called when counters are already disabled.
1816 * xfs_icsb_disable_counter() optimises the counter locking in this case to
1817 * prevent locking every per-cpu counter needlessly.
1818 */
1819
1820#define XFS_ICSB_INO_CNTR_REENABLE (uint64_t)64
1821#define XFS_ICSB_FDBLK_CNTR_REENABLE(mp) \
1822 (uint64_t)(512 + XFS_ALLOC_SET_ASIDE(mp))
1823STATIC void
1824xfs_icsb_balance_counter_locked(
1825 xfs_mount_t *mp,
1826 xfs_sb_field_t field,
1827 int min_per_cpu)
1828{
1829 uint64_t count, resid;
1830 int weight = num_online_cpus();
1831 uint64_t min = (uint64_t)min_per_cpu;
1832
1833 /* disable counter and sync counter */
1834 xfs_icsb_disable_counter(mp, field);
1835
1836 /* update counters - first CPU gets residual*/
1837 switch (field) {
1838 case XFS_SBS_ICOUNT:
1839 count = mp->m_sb.sb_icount;
1840 resid = do_div(count, weight);
1841 if (count < max(min, XFS_ICSB_INO_CNTR_REENABLE))
1842 return;
1843 break;
1844 case XFS_SBS_IFREE:
1845 count = mp->m_sb.sb_ifree;
1846 resid = do_div(count, weight);
1847 if (count < max(min, XFS_ICSB_INO_CNTR_REENABLE))
1848 return;
1849 break;
1850 case XFS_SBS_FDBLOCKS:
1851 count = mp->m_sb.sb_fdblocks;
1852 resid = do_div(count, weight);
1853 if (count < max(min, XFS_ICSB_FDBLK_CNTR_REENABLE(mp)))
1854 return;
1855 break;
1856 default:
1857 BUG();
1858 count = resid = 0; /* quiet, gcc */
1859 break;
1860 }
1861
1862 xfs_icsb_enable_counter(mp, field, count, resid);
1863}
1864
1865STATIC void
1866xfs_icsb_balance_counter(
1867 xfs_mount_t *mp,
1868 xfs_sb_field_t fields,
1869 int min_per_cpu)
1870{
1871 spin_lock(&mp->m_sb_lock);
1872 xfs_icsb_balance_counter_locked(mp, fields, min_per_cpu);
1873 spin_unlock(&mp->m_sb_lock);
1874}
1875
1876int
1877xfs_icsb_modify_counters(
1878 xfs_mount_t *mp,
1879 xfs_sb_field_t field,
1880 int64_t delta,
1881 int rsvd)
1882{
1883 xfs_icsb_cnts_t *icsbp;
1884 long long lcounter; /* long counter for 64 bit fields */
1885 int ret = 0;
1886
1887 might_sleep();
1888again:
1889 preempt_disable();
1890 icsbp = this_cpu_ptr(mp->m_sb_cnts);
1891
1892 /*
1893 * if the counter is disabled, go to slow path
1894 */
1895 if (unlikely(xfs_icsb_counter_disabled(mp, field)))
1896 goto slow_path;
1897 xfs_icsb_lock_cntr(icsbp);
1898 if (unlikely(xfs_icsb_counter_disabled(mp, field))) {
1899 xfs_icsb_unlock_cntr(icsbp);
1900 goto slow_path;
1901 }
1902
1903 switch (field) {
1904 case XFS_SBS_ICOUNT:
1905 lcounter = icsbp->icsb_icount;
1906 lcounter += delta;
1907 if (unlikely(lcounter < 0))
1908 goto balance_counter;
1909 icsbp->icsb_icount = lcounter;
1910 break;
1911
1912 case XFS_SBS_IFREE:
1913 lcounter = icsbp->icsb_ifree;
1914 lcounter += delta;
1915 if (unlikely(lcounter < 0))
1916 goto balance_counter;
1917 icsbp->icsb_ifree = lcounter;
1918 break;
1919
1920 case XFS_SBS_FDBLOCKS:
1921 BUG_ON((mp->m_resblks - mp->m_resblks_avail) != 0);
1922
1923 lcounter = icsbp->icsb_fdblocks - XFS_ALLOC_SET_ASIDE(mp);
1924 lcounter += delta;
1925 if (unlikely(lcounter < 0))
1926 goto balance_counter;
1927 icsbp->icsb_fdblocks = lcounter + XFS_ALLOC_SET_ASIDE(mp);
1928 break;
1929 default:
1930 BUG();
1931 break;
1932 }
1933 xfs_icsb_unlock_cntr(icsbp);
1934 preempt_enable();
1935 return 0;
1936
1937slow_path:
1938 preempt_enable();
1939
1940 /*
1941 * serialise with a mutex so we don't burn lots of cpu on
1942 * the superblock lock. We still need to hold the superblock
1943 * lock, however, when we modify the global structures.
1944 */
1945 xfs_icsb_lock(mp);
1946
1947 /*
1948 * Now running atomically.
1949 *
1950 * If the counter is enabled, someone has beaten us to rebalancing.
1951 * Drop the lock and try again in the fast path....
1952 */
1953 if (!(xfs_icsb_counter_disabled(mp, field))) {
1954 xfs_icsb_unlock(mp);
1955 goto again;
1956 }
1957
1958 /*
1959 * The counter is currently disabled. Because we are
1960 * running atomically here, we know a rebalance cannot
1961 * be in progress. Hence we can go straight to operating
1962 * on the global superblock. We do not call xfs_mod_incore_sb()
1963 * here even though we need to get the m_sb_lock. Doing so
1964 * will cause us to re-enter this function and deadlock.
1965 * Hence we get the m_sb_lock ourselves and then call
1966 * xfs_mod_incore_sb_unlocked() as the unlocked path operates
1967 * directly on the global counters.
1968 */
1969 spin_lock(&mp->m_sb_lock);
1970 ret = xfs_mod_incore_sb_unlocked(mp, field, delta, rsvd);
1971 spin_unlock(&mp->m_sb_lock);
1972
1973 /*
1974 * Now that we've modified the global superblock, we
1975 * may be able to re-enable the distributed counters
1976 * (e.g. lots of space just got freed). After that
1977 * we are done.
1978 */
1979 if (ret != ENOSPC)
1980 xfs_icsb_balance_counter(mp, field, 0);
1981 xfs_icsb_unlock(mp);
1982 return ret;
1983
1984balance_counter:
1985 xfs_icsb_unlock_cntr(icsbp);
1986 preempt_enable();
1987
1988 /*
1989 * We may have multiple threads here if multiple per-cpu
1990 * counters run dry at the same time. This will mean we can
1991 * do more balances than strictly necessary but it is not
1992 * the common slowpath case.
1993 */
1994 xfs_icsb_lock(mp);
1995
1996 /*
1997 * running atomically.
1998 *
1999 * This will leave the counter in the correct state for future
2000 * accesses. After the rebalance, we simply try again and our retry
2001 * will either succeed through the fast path or slow path without
2002 * another balance operation being required.
2003 */
2004 xfs_icsb_balance_counter(mp, field, delta);
2005 xfs_icsb_unlock(mp);
2006 goto again;
2007}
2008
2009#endif