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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6#include "xfs.h"
7#include "xfs_fs.h"
8#include "xfs_shared.h"
9#include "xfs_format.h"
10#include "xfs_log_format.h"
11#include "xfs_trans_resv.h"
12#include "xfs_bit.h"
13#include "xfs_sb.h"
14#include "xfs_mount.h"
15#include "xfs_inode.h"
16#include "xfs_dir2.h"
17#include "xfs_ialloc.h"
18#include "xfs_alloc.h"
19#include "xfs_rtalloc.h"
20#include "xfs_bmap.h"
21#include "xfs_trans.h"
22#include "xfs_trans_priv.h"
23#include "xfs_log.h"
24#include "xfs_log_priv.h"
25#include "xfs_error.h"
26#include "xfs_quota.h"
27#include "xfs_fsops.h"
28#include "xfs_icache.h"
29#include "xfs_sysfs.h"
30#include "xfs_rmap_btree.h"
31#include "xfs_refcount_btree.h"
32#include "xfs_reflink.h"
33#include "xfs_extent_busy.h"
34#include "xfs_health.h"
35#include "xfs_trace.h"
36#include "xfs_ag.h"
37#include "scrub/stats.h"
38
39static DEFINE_MUTEX(xfs_uuid_table_mutex);
40static int xfs_uuid_table_size;
41static uuid_t *xfs_uuid_table;
42
43void
44xfs_uuid_table_free(void)
45{
46 if (xfs_uuid_table_size == 0)
47 return;
48 kfree(xfs_uuid_table);
49 xfs_uuid_table = NULL;
50 xfs_uuid_table_size = 0;
51}
52
53/*
54 * See if the UUID is unique among mounted XFS filesystems.
55 * Mount fails if UUID is nil or a FS with the same UUID is already mounted.
56 */
57STATIC int
58xfs_uuid_mount(
59 struct xfs_mount *mp)
60{
61 uuid_t *uuid = &mp->m_sb.sb_uuid;
62 int hole, i;
63
64 /* Publish UUID in struct super_block */
65 super_set_uuid(mp->m_super, uuid->b, sizeof(*uuid));
66
67 if (xfs_has_nouuid(mp))
68 return 0;
69
70 if (uuid_is_null(uuid)) {
71 xfs_warn(mp, "Filesystem has null UUID - can't mount");
72 return -EINVAL;
73 }
74
75 mutex_lock(&xfs_uuid_table_mutex);
76 for (i = 0, hole = -1; i < xfs_uuid_table_size; i++) {
77 if (uuid_is_null(&xfs_uuid_table[i])) {
78 hole = i;
79 continue;
80 }
81 if (uuid_equal(uuid, &xfs_uuid_table[i]))
82 goto out_duplicate;
83 }
84
85 if (hole < 0) {
86 xfs_uuid_table = krealloc(xfs_uuid_table,
87 (xfs_uuid_table_size + 1) * sizeof(*xfs_uuid_table),
88 GFP_KERNEL | __GFP_NOFAIL);
89 hole = xfs_uuid_table_size++;
90 }
91 xfs_uuid_table[hole] = *uuid;
92 mutex_unlock(&xfs_uuid_table_mutex);
93
94 return 0;
95
96 out_duplicate:
97 mutex_unlock(&xfs_uuid_table_mutex);
98 xfs_warn(mp, "Filesystem has duplicate UUID %pU - can't mount", uuid);
99 return -EINVAL;
100}
101
102STATIC void
103xfs_uuid_unmount(
104 struct xfs_mount *mp)
105{
106 uuid_t *uuid = &mp->m_sb.sb_uuid;
107 int i;
108
109 if (xfs_has_nouuid(mp))
110 return;
111
112 mutex_lock(&xfs_uuid_table_mutex);
113 for (i = 0; i < xfs_uuid_table_size; i++) {
114 if (uuid_is_null(&xfs_uuid_table[i]))
115 continue;
116 if (!uuid_equal(uuid, &xfs_uuid_table[i]))
117 continue;
118 memset(&xfs_uuid_table[i], 0, sizeof(uuid_t));
119 break;
120 }
121 ASSERT(i < xfs_uuid_table_size);
122 mutex_unlock(&xfs_uuid_table_mutex);
123}
124
125/*
126 * Check size of device based on the (data/realtime) block count.
127 * Note: this check is used by the growfs code as well as mount.
128 */
129int
130xfs_sb_validate_fsb_count(
131 xfs_sb_t *sbp,
132 uint64_t nblocks)
133{
134 ASSERT(PAGE_SHIFT >= sbp->sb_blocklog);
135 ASSERT(sbp->sb_blocklog >= BBSHIFT);
136
137 /* Limited by ULONG_MAX of page cache index */
138 if (nblocks >> (PAGE_SHIFT - sbp->sb_blocklog) > ULONG_MAX)
139 return -EFBIG;
140 return 0;
141}
142
143/*
144 * xfs_readsb
145 *
146 * Does the initial read of the superblock.
147 */
148int
149xfs_readsb(
150 struct xfs_mount *mp,
151 int flags)
152{
153 unsigned int sector_size;
154 struct xfs_buf *bp;
155 struct xfs_sb *sbp = &mp->m_sb;
156 int error;
157 int loud = !(flags & XFS_MFSI_QUIET);
158 const struct xfs_buf_ops *buf_ops;
159
160 ASSERT(mp->m_sb_bp == NULL);
161 ASSERT(mp->m_ddev_targp != NULL);
162
163 /*
164 * For the initial read, we must guess at the sector
165 * size based on the block device. It's enough to
166 * get the sb_sectsize out of the superblock and
167 * then reread with the proper length.
168 * We don't verify it yet, because it may not be complete.
169 */
170 sector_size = xfs_getsize_buftarg(mp->m_ddev_targp);
171 buf_ops = NULL;
172
173 /*
174 * Allocate a (locked) buffer to hold the superblock. This will be kept
175 * around at all times to optimize access to the superblock. Therefore,
176 * set XBF_NO_IOACCT to make sure it doesn't hold the buftarg count
177 * elevated.
178 */
179reread:
180 error = xfs_buf_read_uncached(mp->m_ddev_targp, XFS_SB_DADDR,
181 BTOBB(sector_size), XBF_NO_IOACCT, &bp,
182 buf_ops);
183 if (error) {
184 if (loud)
185 xfs_warn(mp, "SB validate failed with error %d.", error);
186 /* bad CRC means corrupted metadata */
187 if (error == -EFSBADCRC)
188 error = -EFSCORRUPTED;
189 return error;
190 }
191
192 /*
193 * Initialize the mount structure from the superblock.
194 */
195 xfs_sb_from_disk(sbp, bp->b_addr);
196
197 /*
198 * If we haven't validated the superblock, do so now before we try
199 * to check the sector size and reread the superblock appropriately.
200 */
201 if (sbp->sb_magicnum != XFS_SB_MAGIC) {
202 if (loud)
203 xfs_warn(mp, "Invalid superblock magic number");
204 error = -EINVAL;
205 goto release_buf;
206 }
207
208 /*
209 * We must be able to do sector-sized and sector-aligned IO.
210 */
211 if (sector_size > sbp->sb_sectsize) {
212 if (loud)
213 xfs_warn(mp, "device supports %u byte sectors (not %u)",
214 sector_size, sbp->sb_sectsize);
215 error = -ENOSYS;
216 goto release_buf;
217 }
218
219 if (buf_ops == NULL) {
220 /*
221 * Re-read the superblock so the buffer is correctly sized,
222 * and properly verified.
223 */
224 xfs_buf_relse(bp);
225 sector_size = sbp->sb_sectsize;
226 buf_ops = loud ? &xfs_sb_buf_ops : &xfs_sb_quiet_buf_ops;
227 goto reread;
228 }
229
230 mp->m_features |= xfs_sb_version_to_features(sbp);
231 xfs_reinit_percpu_counters(mp);
232
233 /* no need to be quiet anymore, so reset the buf ops */
234 bp->b_ops = &xfs_sb_buf_ops;
235
236 mp->m_sb_bp = bp;
237 xfs_buf_unlock(bp);
238 return 0;
239
240release_buf:
241 xfs_buf_relse(bp);
242 return error;
243}
244
245/*
246 * If the sunit/swidth change would move the precomputed root inode value, we
247 * must reject the ondisk change because repair will stumble over that.
248 * However, we allow the mount to proceed because we never rejected this
249 * combination before. Returns true to update the sb, false otherwise.
250 */
251static inline int
252xfs_check_new_dalign(
253 struct xfs_mount *mp,
254 int new_dalign,
255 bool *update_sb)
256{
257 struct xfs_sb *sbp = &mp->m_sb;
258 xfs_ino_t calc_ino;
259
260 calc_ino = xfs_ialloc_calc_rootino(mp, new_dalign);
261 trace_xfs_check_new_dalign(mp, new_dalign, calc_ino);
262
263 if (sbp->sb_rootino == calc_ino) {
264 *update_sb = true;
265 return 0;
266 }
267
268 xfs_warn(mp,
269"Cannot change stripe alignment; would require moving root inode.");
270
271 /*
272 * XXX: Next time we add a new incompat feature, this should start
273 * returning -EINVAL to fail the mount. Until then, spit out a warning
274 * that we're ignoring the administrator's instructions.
275 */
276 xfs_warn(mp, "Skipping superblock stripe alignment update.");
277 *update_sb = false;
278 return 0;
279}
280
281/*
282 * If we were provided with new sunit/swidth values as mount options, make sure
283 * that they pass basic alignment and superblock feature checks, and convert
284 * them into the same units (FSB) that everything else expects. This step
285 * /must/ be done before computing the inode geometry.
286 */
287STATIC int
288xfs_validate_new_dalign(
289 struct xfs_mount *mp)
290{
291 if (mp->m_dalign == 0)
292 return 0;
293
294 /*
295 * If stripe unit and stripe width are not multiples
296 * of the fs blocksize turn off alignment.
297 */
298 if ((BBTOB(mp->m_dalign) & mp->m_blockmask) ||
299 (BBTOB(mp->m_swidth) & mp->m_blockmask)) {
300 xfs_warn(mp,
301 "alignment check failed: sunit/swidth vs. blocksize(%d)",
302 mp->m_sb.sb_blocksize);
303 return -EINVAL;
304 }
305
306 /*
307 * Convert the stripe unit and width to FSBs.
308 */
309 mp->m_dalign = XFS_BB_TO_FSBT(mp, mp->m_dalign);
310 if (mp->m_dalign && (mp->m_sb.sb_agblocks % mp->m_dalign)) {
311 xfs_warn(mp,
312 "alignment check failed: sunit/swidth vs. agsize(%d)",
313 mp->m_sb.sb_agblocks);
314 return -EINVAL;
315 }
316
317 if (!mp->m_dalign) {
318 xfs_warn(mp,
319 "alignment check failed: sunit(%d) less than bsize(%d)",
320 mp->m_dalign, mp->m_sb.sb_blocksize);
321 return -EINVAL;
322 }
323
324 mp->m_swidth = XFS_BB_TO_FSBT(mp, mp->m_swidth);
325
326 if (!xfs_has_dalign(mp)) {
327 xfs_warn(mp,
328"cannot change alignment: superblock does not support data alignment");
329 return -EINVAL;
330 }
331
332 return 0;
333}
334
335/* Update alignment values based on mount options and sb values. */
336STATIC int
337xfs_update_alignment(
338 struct xfs_mount *mp)
339{
340 struct xfs_sb *sbp = &mp->m_sb;
341
342 if (mp->m_dalign) {
343 bool update_sb;
344 int error;
345
346 if (sbp->sb_unit == mp->m_dalign &&
347 sbp->sb_width == mp->m_swidth)
348 return 0;
349
350 error = xfs_check_new_dalign(mp, mp->m_dalign, &update_sb);
351 if (error || !update_sb)
352 return error;
353
354 sbp->sb_unit = mp->m_dalign;
355 sbp->sb_width = mp->m_swidth;
356 mp->m_update_sb = true;
357 } else if (!xfs_has_noalign(mp) && xfs_has_dalign(mp)) {
358 mp->m_dalign = sbp->sb_unit;
359 mp->m_swidth = sbp->sb_width;
360 }
361
362 return 0;
363}
364
365/*
366 * precalculate the low space thresholds for dynamic speculative preallocation.
367 */
368void
369xfs_set_low_space_thresholds(
370 struct xfs_mount *mp)
371{
372 uint64_t dblocks = mp->m_sb.sb_dblocks;
373 uint64_t rtexts = mp->m_sb.sb_rextents;
374 int i;
375
376 do_div(dblocks, 100);
377 do_div(rtexts, 100);
378
379 for (i = 0; i < XFS_LOWSP_MAX; i++) {
380 mp->m_low_space[i] = dblocks * (i + 1);
381 mp->m_low_rtexts[i] = rtexts * (i + 1);
382 }
383}
384
385/*
386 * Check that the data (and log if separate) is an ok size.
387 */
388STATIC int
389xfs_check_sizes(
390 struct xfs_mount *mp)
391{
392 struct xfs_buf *bp;
393 xfs_daddr_t d;
394 int error;
395
396 d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks);
397 if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_dblocks) {
398 xfs_warn(mp, "filesystem size mismatch detected");
399 return -EFBIG;
400 }
401 error = xfs_buf_read_uncached(mp->m_ddev_targp,
402 d - XFS_FSS_TO_BB(mp, 1),
403 XFS_FSS_TO_BB(mp, 1), 0, &bp, NULL);
404 if (error) {
405 xfs_warn(mp, "last sector read failed");
406 return error;
407 }
408 xfs_buf_relse(bp);
409
410 if (mp->m_logdev_targp == mp->m_ddev_targp)
411 return 0;
412
413 d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_logblocks);
414 if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_logblocks) {
415 xfs_warn(mp, "log size mismatch detected");
416 return -EFBIG;
417 }
418 error = xfs_buf_read_uncached(mp->m_logdev_targp,
419 d - XFS_FSB_TO_BB(mp, 1),
420 XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
421 if (error) {
422 xfs_warn(mp, "log device read failed");
423 return error;
424 }
425 xfs_buf_relse(bp);
426 return 0;
427}
428
429/*
430 * Clear the quotaflags in memory and in the superblock.
431 */
432int
433xfs_mount_reset_sbqflags(
434 struct xfs_mount *mp)
435{
436 mp->m_qflags = 0;
437
438 /* It is OK to look at sb_qflags in the mount path without m_sb_lock. */
439 if (mp->m_sb.sb_qflags == 0)
440 return 0;
441 spin_lock(&mp->m_sb_lock);
442 mp->m_sb.sb_qflags = 0;
443 spin_unlock(&mp->m_sb_lock);
444
445 if (!xfs_fs_writable(mp, SB_FREEZE_WRITE))
446 return 0;
447
448 return xfs_sync_sb(mp, false);
449}
450
451uint64_t
452xfs_default_resblks(xfs_mount_t *mp)
453{
454 uint64_t resblks;
455
456 /*
457 * We default to 5% or 8192 fsbs of space reserved, whichever is
458 * smaller. This is intended to cover concurrent allocation
459 * transactions when we initially hit enospc. These each require a 4
460 * block reservation. Hence by default we cover roughly 2000 concurrent
461 * allocation reservations.
462 */
463 resblks = mp->m_sb.sb_dblocks;
464 do_div(resblks, 20);
465 resblks = min_t(uint64_t, resblks, 8192);
466 return resblks;
467}
468
469/* Ensure the summary counts are correct. */
470STATIC int
471xfs_check_summary_counts(
472 struct xfs_mount *mp)
473{
474 int error = 0;
475
476 /*
477 * The AG0 superblock verifier rejects in-progress filesystems,
478 * so we should never see the flag set this far into mounting.
479 */
480 if (mp->m_sb.sb_inprogress) {
481 xfs_err(mp, "sb_inprogress set after log recovery??");
482 WARN_ON(1);
483 return -EFSCORRUPTED;
484 }
485
486 /*
487 * Now the log is mounted, we know if it was an unclean shutdown or
488 * not. If it was, with the first phase of recovery has completed, we
489 * have consistent AG blocks on disk. We have not recovered EFIs yet,
490 * but they are recovered transactionally in the second recovery phase
491 * later.
492 *
493 * If the log was clean when we mounted, we can check the summary
494 * counters. If any of them are obviously incorrect, we can recompute
495 * them from the AGF headers in the next step.
496 */
497 if (xfs_is_clean(mp) &&
498 (mp->m_sb.sb_fdblocks > mp->m_sb.sb_dblocks ||
499 !xfs_verify_icount(mp, mp->m_sb.sb_icount) ||
500 mp->m_sb.sb_ifree > mp->m_sb.sb_icount))
501 xfs_fs_mark_sick(mp, XFS_SICK_FS_COUNTERS);
502
503 /*
504 * We can safely re-initialise incore superblock counters from the
505 * per-ag data. These may not be correct if the filesystem was not
506 * cleanly unmounted, so we waited for recovery to finish before doing
507 * this.
508 *
509 * If the filesystem was cleanly unmounted or the previous check did
510 * not flag anything weird, then we can trust the values in the
511 * superblock to be correct and we don't need to do anything here.
512 * Otherwise, recalculate the summary counters.
513 */
514 if ((xfs_has_lazysbcount(mp) && !xfs_is_clean(mp)) ||
515 xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS)) {
516 error = xfs_initialize_perag_data(mp, mp->m_sb.sb_agcount);
517 if (error)
518 return error;
519 }
520
521 /*
522 * Older kernels misused sb_frextents to reflect both incore
523 * reservations made by running transactions and the actual count of
524 * free rt extents in the ondisk metadata. Transactions committed
525 * during runtime can therefore contain a superblock update that
526 * undercounts the number of free rt extents tracked in the rt bitmap.
527 * A clean unmount record will have the correct frextents value since
528 * there can be no other transactions running at that point.
529 *
530 * If we're mounting the rt volume after recovering the log, recompute
531 * frextents from the rtbitmap file to fix the inconsistency.
532 */
533 if (xfs_has_realtime(mp) && !xfs_is_clean(mp)) {
534 error = xfs_rtalloc_reinit_frextents(mp);
535 if (error)
536 return error;
537 }
538
539 return 0;
540}
541
542static void
543xfs_unmount_check(
544 struct xfs_mount *mp)
545{
546 if (xfs_is_shutdown(mp))
547 return;
548
549 if (percpu_counter_sum(&mp->m_ifree) >
550 percpu_counter_sum(&mp->m_icount)) {
551 xfs_alert(mp, "ifree/icount mismatch at unmount");
552 xfs_fs_mark_sick(mp, XFS_SICK_FS_COUNTERS);
553 }
554}
555
556/*
557 * Flush and reclaim dirty inodes in preparation for unmount. Inodes and
558 * internal inode structures can be sitting in the CIL and AIL at this point,
559 * so we need to unpin them, write them back and/or reclaim them before unmount
560 * can proceed. In other words, callers are required to have inactivated all
561 * inodes.
562 *
563 * An inode cluster that has been freed can have its buffer still pinned in
564 * memory because the transaction is still sitting in a iclog. The stale inodes
565 * on that buffer will be pinned to the buffer until the transaction hits the
566 * disk and the callbacks run. Pushing the AIL will skip the stale inodes and
567 * may never see the pinned buffer, so nothing will push out the iclog and
568 * unpin the buffer.
569 *
570 * Hence we need to force the log to unpin everything first. However, log
571 * forces don't wait for the discards they issue to complete, so we have to
572 * explicitly wait for them to complete here as well.
573 *
574 * Then we can tell the world we are unmounting so that error handling knows
575 * that the filesystem is going away and we should error out anything that we
576 * have been retrying in the background. This will prevent never-ending
577 * retries in AIL pushing from hanging the unmount.
578 *
579 * Finally, we can push the AIL to clean all the remaining dirty objects, then
580 * reclaim the remaining inodes that are still in memory at this point in time.
581 */
582static void
583xfs_unmount_flush_inodes(
584 struct xfs_mount *mp)
585{
586 xfs_log_force(mp, XFS_LOG_SYNC);
587 xfs_extent_busy_wait_all(mp);
588 flush_workqueue(xfs_discard_wq);
589
590 set_bit(XFS_OPSTATE_UNMOUNTING, &mp->m_opstate);
591
592 xfs_ail_push_all_sync(mp->m_ail);
593 xfs_inodegc_stop(mp);
594 cancel_delayed_work_sync(&mp->m_reclaim_work);
595 xfs_reclaim_inodes(mp);
596 xfs_health_unmount(mp);
597}
598
599static void
600xfs_mount_setup_inode_geom(
601 struct xfs_mount *mp)
602{
603 struct xfs_ino_geometry *igeo = M_IGEO(mp);
604
605 igeo->attr_fork_offset = xfs_bmap_compute_attr_offset(mp);
606 ASSERT(igeo->attr_fork_offset < XFS_LITINO(mp));
607
608 xfs_ialloc_setup_geometry(mp);
609}
610
611/* Compute maximum possible height for per-AG btree types for this fs. */
612static inline void
613xfs_agbtree_compute_maxlevels(
614 struct xfs_mount *mp)
615{
616 unsigned int levels;
617
618 levels = max(mp->m_alloc_maxlevels, M_IGEO(mp)->inobt_maxlevels);
619 levels = max(levels, mp->m_rmap_maxlevels);
620 mp->m_agbtree_maxlevels = max(levels, mp->m_refc_maxlevels);
621}
622
623/*
624 * This function does the following on an initial mount of a file system:
625 * - reads the superblock from disk and init the mount struct
626 * - if we're a 32-bit kernel, do a size check on the superblock
627 * so we don't mount terabyte filesystems
628 * - init mount struct realtime fields
629 * - allocate inode hash table for fs
630 * - init directory manager
631 * - perform recovery and init the log manager
632 */
633int
634xfs_mountfs(
635 struct xfs_mount *mp)
636{
637 struct xfs_sb *sbp = &(mp->m_sb);
638 struct xfs_inode *rip;
639 struct xfs_ino_geometry *igeo = M_IGEO(mp);
640 uint quotamount = 0;
641 uint quotaflags = 0;
642 int error = 0;
643
644 xfs_sb_mount_common(mp, sbp);
645
646 /*
647 * Check for a mismatched features2 values. Older kernels read & wrote
648 * into the wrong sb offset for sb_features2 on some platforms due to
649 * xfs_sb_t not being 64bit size aligned when sb_features2 was added,
650 * which made older superblock reading/writing routines swap it as a
651 * 64-bit value.
652 *
653 * For backwards compatibility, we make both slots equal.
654 *
655 * If we detect a mismatched field, we OR the set bits into the existing
656 * features2 field in case it has already been modified; we don't want
657 * to lose any features. We then update the bad location with the ORed
658 * value so that older kernels will see any features2 flags. The
659 * superblock writeback code ensures the new sb_features2 is copied to
660 * sb_bad_features2 before it is logged or written to disk.
661 */
662 if (xfs_sb_has_mismatched_features2(sbp)) {
663 xfs_warn(mp, "correcting sb_features alignment problem");
664 sbp->sb_features2 |= sbp->sb_bad_features2;
665 mp->m_update_sb = true;
666 }
667
668
669 /* always use v2 inodes by default now */
670 if (!(mp->m_sb.sb_versionnum & XFS_SB_VERSION_NLINKBIT)) {
671 mp->m_sb.sb_versionnum |= XFS_SB_VERSION_NLINKBIT;
672 mp->m_features |= XFS_FEAT_NLINK;
673 mp->m_update_sb = true;
674 }
675
676 /*
677 * If we were given new sunit/swidth options, do some basic validation
678 * checks and convert the incore dalign and swidth values to the
679 * same units (FSB) that everything else uses. This /must/ happen
680 * before computing the inode geometry.
681 */
682 error = xfs_validate_new_dalign(mp);
683 if (error)
684 goto out;
685
686 xfs_alloc_compute_maxlevels(mp);
687 xfs_bmap_compute_maxlevels(mp, XFS_DATA_FORK);
688 xfs_bmap_compute_maxlevels(mp, XFS_ATTR_FORK);
689 xfs_mount_setup_inode_geom(mp);
690 xfs_rmapbt_compute_maxlevels(mp);
691 xfs_refcountbt_compute_maxlevels(mp);
692
693 xfs_agbtree_compute_maxlevels(mp);
694
695 /*
696 * Check if sb_agblocks is aligned at stripe boundary. If sb_agblocks
697 * is NOT aligned turn off m_dalign since allocator alignment is within
698 * an ag, therefore ag has to be aligned at stripe boundary. Note that
699 * we must compute the free space and rmap btree geometry before doing
700 * this.
701 */
702 error = xfs_update_alignment(mp);
703 if (error)
704 goto out;
705
706 /* enable fail_at_unmount as default */
707 mp->m_fail_unmount = true;
708
709 super_set_sysfs_name_id(mp->m_super);
710
711 error = xfs_sysfs_init(&mp->m_kobj, &xfs_mp_ktype,
712 NULL, mp->m_super->s_id);
713 if (error)
714 goto out;
715
716 error = xfs_sysfs_init(&mp->m_stats.xs_kobj, &xfs_stats_ktype,
717 &mp->m_kobj, "stats");
718 if (error)
719 goto out_remove_sysfs;
720
721 xchk_stats_register(mp->m_scrub_stats, mp->m_debugfs);
722
723 error = xfs_error_sysfs_init(mp);
724 if (error)
725 goto out_remove_scrub_stats;
726
727 error = xfs_errortag_init(mp);
728 if (error)
729 goto out_remove_error_sysfs;
730
731 error = xfs_uuid_mount(mp);
732 if (error)
733 goto out_remove_errortag;
734
735 /*
736 * Update the preferred write size based on the information from the
737 * on-disk superblock.
738 */
739 mp->m_allocsize_log =
740 max_t(uint32_t, sbp->sb_blocklog, mp->m_allocsize_log);
741 mp->m_allocsize_blocks = 1U << (mp->m_allocsize_log - sbp->sb_blocklog);
742
743 /* set the low space thresholds for dynamic preallocation */
744 xfs_set_low_space_thresholds(mp);
745
746 /*
747 * If enabled, sparse inode chunk alignment is expected to match the
748 * cluster size. Full inode chunk alignment must match the chunk size,
749 * but that is checked on sb read verification...
750 */
751 if (xfs_has_sparseinodes(mp) &&
752 mp->m_sb.sb_spino_align !=
753 XFS_B_TO_FSBT(mp, igeo->inode_cluster_size_raw)) {
754 xfs_warn(mp,
755 "Sparse inode block alignment (%u) must match cluster size (%llu).",
756 mp->m_sb.sb_spino_align,
757 XFS_B_TO_FSBT(mp, igeo->inode_cluster_size_raw));
758 error = -EINVAL;
759 goto out_remove_uuid;
760 }
761
762 /*
763 * Check that the data (and log if separate) is an ok size.
764 */
765 error = xfs_check_sizes(mp);
766 if (error)
767 goto out_remove_uuid;
768
769 /*
770 * Initialize realtime fields in the mount structure
771 */
772 error = xfs_rtmount_init(mp);
773 if (error) {
774 xfs_warn(mp, "RT mount failed");
775 goto out_remove_uuid;
776 }
777
778 /*
779 * Copies the low order bits of the timestamp and the randomly
780 * set "sequence" number out of a UUID.
781 */
782 mp->m_fixedfsid[0] =
783 (get_unaligned_be16(&sbp->sb_uuid.b[8]) << 16) |
784 get_unaligned_be16(&sbp->sb_uuid.b[4]);
785 mp->m_fixedfsid[1] = get_unaligned_be32(&sbp->sb_uuid.b[0]);
786
787 error = xfs_da_mount(mp);
788 if (error) {
789 xfs_warn(mp, "Failed dir/attr init: %d", error);
790 goto out_remove_uuid;
791 }
792
793 /*
794 * Initialize the precomputed transaction reservations values.
795 */
796 xfs_trans_init(mp);
797
798 /*
799 * Allocate and initialize the per-ag data.
800 */
801 error = xfs_initialize_perag(mp, sbp->sb_agcount, mp->m_sb.sb_dblocks,
802 &mp->m_maxagi);
803 if (error) {
804 xfs_warn(mp, "Failed per-ag init: %d", error);
805 goto out_free_dir;
806 }
807
808 if (XFS_IS_CORRUPT(mp, !sbp->sb_logblocks)) {
809 xfs_warn(mp, "no log defined");
810 error = -EFSCORRUPTED;
811 goto out_free_perag;
812 }
813
814 error = xfs_inodegc_register_shrinker(mp);
815 if (error)
816 goto out_fail_wait;
817
818 /*
819 * Log's mount-time initialization. The first part of recovery can place
820 * some items on the AIL, to be handled when recovery is finished or
821 * cancelled.
822 */
823 error = xfs_log_mount(mp, mp->m_logdev_targp,
824 XFS_FSB_TO_DADDR(mp, sbp->sb_logstart),
825 XFS_FSB_TO_BB(mp, sbp->sb_logblocks));
826 if (error) {
827 xfs_warn(mp, "log mount failed");
828 goto out_inodegc_shrinker;
829 }
830
831 /* Enable background inode inactivation workers. */
832 xfs_inodegc_start(mp);
833 xfs_blockgc_start(mp);
834
835 /*
836 * Now that we've recovered any pending superblock feature bit
837 * additions, we can finish setting up the attr2 behaviour for the
838 * mount. The noattr2 option overrides the superblock flag, so only
839 * check the superblock feature flag if the mount option is not set.
840 */
841 if (xfs_has_noattr2(mp)) {
842 mp->m_features &= ~XFS_FEAT_ATTR2;
843 } else if (!xfs_has_attr2(mp) &&
844 (mp->m_sb.sb_features2 & XFS_SB_VERSION2_ATTR2BIT)) {
845 mp->m_features |= XFS_FEAT_ATTR2;
846 }
847
848 /*
849 * Get and sanity-check the root inode.
850 * Save the pointer to it in the mount structure.
851 */
852 error = xfs_iget(mp, NULL, sbp->sb_rootino, XFS_IGET_UNTRUSTED,
853 XFS_ILOCK_EXCL, &rip);
854 if (error) {
855 xfs_warn(mp,
856 "Failed to read root inode 0x%llx, error %d",
857 sbp->sb_rootino, -error);
858 goto out_log_dealloc;
859 }
860
861 ASSERT(rip != NULL);
862
863 if (XFS_IS_CORRUPT(mp, !S_ISDIR(VFS_I(rip)->i_mode))) {
864 xfs_warn(mp, "corrupted root inode %llu: not a directory",
865 (unsigned long long)rip->i_ino);
866 xfs_iunlock(rip, XFS_ILOCK_EXCL);
867 error = -EFSCORRUPTED;
868 goto out_rele_rip;
869 }
870 mp->m_rootip = rip; /* save it */
871
872 xfs_iunlock(rip, XFS_ILOCK_EXCL);
873
874 /*
875 * Initialize realtime inode pointers in the mount structure
876 */
877 error = xfs_rtmount_inodes(mp);
878 if (error) {
879 /*
880 * Free up the root inode.
881 */
882 xfs_warn(mp, "failed to read RT inodes");
883 goto out_rele_rip;
884 }
885
886 /* Make sure the summary counts are ok. */
887 error = xfs_check_summary_counts(mp);
888 if (error)
889 goto out_rtunmount;
890
891 /*
892 * If this is a read-only mount defer the superblock updates until
893 * the next remount into writeable mode. Otherwise we would never
894 * perform the update e.g. for the root filesystem.
895 */
896 if (mp->m_update_sb && !xfs_is_readonly(mp)) {
897 error = xfs_sync_sb(mp, false);
898 if (error) {
899 xfs_warn(mp, "failed to write sb changes");
900 goto out_rtunmount;
901 }
902 }
903
904 /*
905 * Initialise the XFS quota management subsystem for this mount
906 */
907 if (XFS_IS_QUOTA_ON(mp)) {
908 error = xfs_qm_newmount(mp, "amount, "aflags);
909 if (error)
910 goto out_rtunmount;
911 } else {
912 /*
913 * If a file system had quotas running earlier, but decided to
914 * mount without -o uquota/pquota/gquota options, revoke the
915 * quotachecked license.
916 */
917 if (mp->m_sb.sb_qflags & XFS_ALL_QUOTA_ACCT) {
918 xfs_notice(mp, "resetting quota flags");
919 error = xfs_mount_reset_sbqflags(mp);
920 if (error)
921 goto out_rtunmount;
922 }
923 }
924
925 /*
926 * Finish recovering the file system. This part needed to be delayed
927 * until after the root and real-time bitmap inodes were consistently
928 * read in. Temporarily create per-AG space reservations for metadata
929 * btree shape changes because space freeing transactions (for inode
930 * inactivation) require the per-AG reservation in lieu of reserving
931 * blocks.
932 */
933 error = xfs_fs_reserve_ag_blocks(mp);
934 if (error && error == -ENOSPC)
935 xfs_warn(mp,
936 "ENOSPC reserving per-AG metadata pool, log recovery may fail.");
937 error = xfs_log_mount_finish(mp);
938 xfs_fs_unreserve_ag_blocks(mp);
939 if (error) {
940 xfs_warn(mp, "log mount finish failed");
941 goto out_rtunmount;
942 }
943
944 /*
945 * Now the log is fully replayed, we can transition to full read-only
946 * mode for read-only mounts. This will sync all the metadata and clean
947 * the log so that the recovery we just performed does not have to be
948 * replayed again on the next mount.
949 *
950 * We use the same quiesce mechanism as the rw->ro remount, as they are
951 * semantically identical operations.
952 */
953 if (xfs_is_readonly(mp) && !xfs_has_norecovery(mp))
954 xfs_log_clean(mp);
955
956 /*
957 * Complete the quota initialisation, post-log-replay component.
958 */
959 if (quotamount) {
960 ASSERT(mp->m_qflags == 0);
961 mp->m_qflags = quotaflags;
962
963 xfs_qm_mount_quotas(mp);
964 }
965
966 /*
967 * Now we are mounted, reserve a small amount of unused space for
968 * privileged transactions. This is needed so that transaction
969 * space required for critical operations can dip into this pool
970 * when at ENOSPC. This is needed for operations like create with
971 * attr, unwritten extent conversion at ENOSPC, etc. Data allocations
972 * are not allowed to use this reserved space.
973 *
974 * This may drive us straight to ENOSPC on mount, but that implies
975 * we were already there on the last unmount. Warn if this occurs.
976 */
977 if (!xfs_is_readonly(mp)) {
978 error = xfs_reserve_blocks(mp, xfs_default_resblks(mp));
979 if (error)
980 xfs_warn(mp,
981 "Unable to allocate reserve blocks. Continuing without reserve pool.");
982
983 /* Reserve AG blocks for future btree expansion. */
984 error = xfs_fs_reserve_ag_blocks(mp);
985 if (error && error != -ENOSPC)
986 goto out_agresv;
987 }
988
989 return 0;
990
991 out_agresv:
992 xfs_fs_unreserve_ag_blocks(mp);
993 xfs_qm_unmount_quotas(mp);
994 out_rtunmount:
995 xfs_rtunmount_inodes(mp);
996 out_rele_rip:
997 xfs_irele(rip);
998 /* Clean out dquots that might be in memory after quotacheck. */
999 xfs_qm_unmount(mp);
1000
1001 /*
1002 * Inactivate all inodes that might still be in memory after a log
1003 * intent recovery failure so that reclaim can free them. Metadata
1004 * inodes and the root directory shouldn't need inactivation, but the
1005 * mount failed for some reason, so pull down all the state and flee.
1006 */
1007 xfs_inodegc_flush(mp);
1008
1009 /*
1010 * Flush all inode reclamation work and flush the log.
1011 * We have to do this /after/ rtunmount and qm_unmount because those
1012 * two will have scheduled delayed reclaim for the rt/quota inodes.
1013 *
1014 * This is slightly different from the unmountfs call sequence
1015 * because we could be tearing down a partially set up mount. In
1016 * particular, if log_mount_finish fails we bail out without calling
1017 * qm_unmount_quotas and therefore rely on qm_unmount to release the
1018 * quota inodes.
1019 */
1020 xfs_unmount_flush_inodes(mp);
1021 out_log_dealloc:
1022 xfs_log_mount_cancel(mp);
1023 out_inodegc_shrinker:
1024 shrinker_free(mp->m_inodegc_shrinker);
1025 out_fail_wait:
1026 if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp)
1027 xfs_buftarg_drain(mp->m_logdev_targp);
1028 xfs_buftarg_drain(mp->m_ddev_targp);
1029 out_free_perag:
1030 xfs_free_perag(mp);
1031 out_free_dir:
1032 xfs_da_unmount(mp);
1033 out_remove_uuid:
1034 xfs_uuid_unmount(mp);
1035 out_remove_errortag:
1036 xfs_errortag_del(mp);
1037 out_remove_error_sysfs:
1038 xfs_error_sysfs_del(mp);
1039 out_remove_scrub_stats:
1040 xchk_stats_unregister(mp->m_scrub_stats);
1041 xfs_sysfs_del(&mp->m_stats.xs_kobj);
1042 out_remove_sysfs:
1043 xfs_sysfs_del(&mp->m_kobj);
1044 out:
1045 return error;
1046}
1047
1048/*
1049 * This flushes out the inodes,dquots and the superblock, unmounts the
1050 * log and makes sure that incore structures are freed.
1051 */
1052void
1053xfs_unmountfs(
1054 struct xfs_mount *mp)
1055{
1056 int error;
1057
1058 /*
1059 * Perform all on-disk metadata updates required to inactivate inodes
1060 * that the VFS evicted earlier in the unmount process. Freeing inodes
1061 * and discarding CoW fork preallocations can cause shape changes to
1062 * the free inode and refcount btrees, respectively, so we must finish
1063 * this before we discard the metadata space reservations. Metadata
1064 * inodes and the root directory do not require inactivation.
1065 */
1066 xfs_inodegc_flush(mp);
1067
1068 xfs_blockgc_stop(mp);
1069 xfs_fs_unreserve_ag_blocks(mp);
1070 xfs_qm_unmount_quotas(mp);
1071 xfs_rtunmount_inodes(mp);
1072 xfs_irele(mp->m_rootip);
1073
1074 xfs_unmount_flush_inodes(mp);
1075
1076 xfs_qm_unmount(mp);
1077
1078 /*
1079 * Unreserve any blocks we have so that when we unmount we don't account
1080 * the reserved free space as used. This is really only necessary for
1081 * lazy superblock counting because it trusts the incore superblock
1082 * counters to be absolutely correct on clean unmount.
1083 *
1084 * We don't bother correcting this elsewhere for lazy superblock
1085 * counting because on mount of an unclean filesystem we reconstruct the
1086 * correct counter value and this is irrelevant.
1087 *
1088 * For non-lazy counter filesystems, this doesn't matter at all because
1089 * we only every apply deltas to the superblock and hence the incore
1090 * value does not matter....
1091 */
1092 error = xfs_reserve_blocks(mp, 0);
1093 if (error)
1094 xfs_warn(mp, "Unable to free reserved block pool. "
1095 "Freespace may not be correct on next mount.");
1096 xfs_unmount_check(mp);
1097
1098 xfs_log_unmount(mp);
1099 xfs_da_unmount(mp);
1100 xfs_uuid_unmount(mp);
1101
1102#if defined(DEBUG)
1103 xfs_errortag_clearall(mp);
1104#endif
1105 shrinker_free(mp->m_inodegc_shrinker);
1106 xfs_free_perag(mp);
1107
1108 xfs_errortag_del(mp);
1109 xfs_error_sysfs_del(mp);
1110 xchk_stats_unregister(mp->m_scrub_stats);
1111 xfs_sysfs_del(&mp->m_stats.xs_kobj);
1112 xfs_sysfs_del(&mp->m_kobj);
1113}
1114
1115/*
1116 * Determine whether modifications can proceed. The caller specifies the minimum
1117 * freeze level for which modifications should not be allowed. This allows
1118 * certain operations to proceed while the freeze sequence is in progress, if
1119 * necessary.
1120 */
1121bool
1122xfs_fs_writable(
1123 struct xfs_mount *mp,
1124 int level)
1125{
1126 ASSERT(level > SB_UNFROZEN);
1127 if ((mp->m_super->s_writers.frozen >= level) ||
1128 xfs_is_shutdown(mp) || xfs_is_readonly(mp))
1129 return false;
1130
1131 return true;
1132}
1133
1134/* Adjust m_fdblocks or m_frextents. */
1135int
1136xfs_mod_freecounter(
1137 struct xfs_mount *mp,
1138 struct percpu_counter *counter,
1139 int64_t delta,
1140 bool rsvd)
1141{
1142 int64_t lcounter;
1143 long long res_used;
1144 uint64_t set_aside = 0;
1145 s32 batch;
1146 bool has_resv_pool;
1147
1148 ASSERT(counter == &mp->m_fdblocks || counter == &mp->m_frextents);
1149 has_resv_pool = (counter == &mp->m_fdblocks);
1150 if (rsvd)
1151 ASSERT(has_resv_pool);
1152
1153 if (delta > 0) {
1154 /*
1155 * If the reserve pool is depleted, put blocks back into it
1156 * first. Most of the time the pool is full.
1157 */
1158 if (likely(!has_resv_pool ||
1159 mp->m_resblks == mp->m_resblks_avail)) {
1160 percpu_counter_add(counter, delta);
1161 return 0;
1162 }
1163
1164 spin_lock(&mp->m_sb_lock);
1165 res_used = (long long)(mp->m_resblks - mp->m_resblks_avail);
1166
1167 if (res_used > delta) {
1168 mp->m_resblks_avail += delta;
1169 } else {
1170 delta -= res_used;
1171 mp->m_resblks_avail = mp->m_resblks;
1172 percpu_counter_add(counter, delta);
1173 }
1174 spin_unlock(&mp->m_sb_lock);
1175 return 0;
1176 }
1177
1178 /*
1179 * Taking blocks away, need to be more accurate the closer we
1180 * are to zero.
1181 *
1182 * If the counter has a value of less than 2 * max batch size,
1183 * then make everything serialise as we are real close to
1184 * ENOSPC.
1185 */
1186 if (__percpu_counter_compare(counter, 2 * XFS_FDBLOCKS_BATCH,
1187 XFS_FDBLOCKS_BATCH) < 0)
1188 batch = 1;
1189 else
1190 batch = XFS_FDBLOCKS_BATCH;
1191
1192 /*
1193 * Set aside allocbt blocks because these blocks are tracked as free
1194 * space but not available for allocation. Technically this means that a
1195 * single reservation cannot consume all remaining free space, but the
1196 * ratio of allocbt blocks to usable free blocks should be rather small.
1197 * The tradeoff without this is that filesystems that maintain high
1198 * perag block reservations can over reserve physical block availability
1199 * and fail physical allocation, which leads to much more serious
1200 * problems (i.e. transaction abort, pagecache discards, etc.) than
1201 * slightly premature -ENOSPC.
1202 */
1203 if (has_resv_pool)
1204 set_aside = xfs_fdblocks_unavailable(mp);
1205 percpu_counter_add_batch(counter, delta, batch);
1206 if (__percpu_counter_compare(counter, set_aside,
1207 XFS_FDBLOCKS_BATCH) >= 0) {
1208 /* we had space! */
1209 return 0;
1210 }
1211
1212 /*
1213 * lock up the sb for dipping into reserves before releasing the space
1214 * that took us to ENOSPC.
1215 */
1216 spin_lock(&mp->m_sb_lock);
1217 percpu_counter_add(counter, -delta);
1218 if (!has_resv_pool || !rsvd)
1219 goto fdblocks_enospc;
1220
1221 lcounter = (long long)mp->m_resblks_avail + delta;
1222 if (lcounter >= 0) {
1223 mp->m_resblks_avail = lcounter;
1224 spin_unlock(&mp->m_sb_lock);
1225 return 0;
1226 }
1227 xfs_warn_once(mp,
1228"Reserve blocks depleted! Consider increasing reserve pool size.");
1229
1230fdblocks_enospc:
1231 spin_unlock(&mp->m_sb_lock);
1232 return -ENOSPC;
1233}
1234
1235/*
1236 * Used to free the superblock along various error paths.
1237 */
1238void
1239xfs_freesb(
1240 struct xfs_mount *mp)
1241{
1242 struct xfs_buf *bp = mp->m_sb_bp;
1243
1244 xfs_buf_lock(bp);
1245 mp->m_sb_bp = NULL;
1246 xfs_buf_relse(bp);
1247}
1248
1249/*
1250 * If the underlying (data/log/rt) device is readonly, there are some
1251 * operations that cannot proceed.
1252 */
1253int
1254xfs_dev_is_read_only(
1255 struct xfs_mount *mp,
1256 char *message)
1257{
1258 if (xfs_readonly_buftarg(mp->m_ddev_targp) ||
1259 xfs_readonly_buftarg(mp->m_logdev_targp) ||
1260 (mp->m_rtdev_targp && xfs_readonly_buftarg(mp->m_rtdev_targp))) {
1261 xfs_notice(mp, "%s required on read-only device.", message);
1262 xfs_notice(mp, "write access unavailable, cannot proceed.");
1263 return -EROFS;
1264 }
1265 return 0;
1266}
1267
1268/* Force the summary counters to be recalculated at next mount. */
1269void
1270xfs_force_summary_recalc(
1271 struct xfs_mount *mp)
1272{
1273 if (!xfs_has_lazysbcount(mp))
1274 return;
1275
1276 xfs_fs_mark_sick(mp, XFS_SICK_FS_COUNTERS);
1277}
1278
1279/*
1280 * Enable a log incompat feature flag in the primary superblock. The caller
1281 * cannot have any other transactions in progress.
1282 */
1283int
1284xfs_add_incompat_log_feature(
1285 struct xfs_mount *mp,
1286 uint32_t feature)
1287{
1288 struct xfs_dsb *dsb;
1289 int error;
1290
1291 ASSERT(hweight32(feature) == 1);
1292 ASSERT(!(feature & XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN));
1293
1294 /*
1295 * Force the log to disk and kick the background AIL thread to reduce
1296 * the chances that the bwrite will stall waiting for the AIL to unpin
1297 * the primary superblock buffer. This isn't a data integrity
1298 * operation, so we don't need a synchronous push.
1299 */
1300 error = xfs_log_force(mp, XFS_LOG_SYNC);
1301 if (error)
1302 return error;
1303 xfs_ail_push_all(mp->m_ail);
1304
1305 /*
1306 * Lock the primary superblock buffer to serialize all callers that
1307 * are trying to set feature bits.
1308 */
1309 xfs_buf_lock(mp->m_sb_bp);
1310 xfs_buf_hold(mp->m_sb_bp);
1311
1312 if (xfs_is_shutdown(mp)) {
1313 error = -EIO;
1314 goto rele;
1315 }
1316
1317 if (xfs_sb_has_incompat_log_feature(&mp->m_sb, feature))
1318 goto rele;
1319
1320 /*
1321 * Write the primary superblock to disk immediately, because we need
1322 * the log_incompat bit to be set in the primary super now to protect
1323 * the log items that we're going to commit later.
1324 */
1325 dsb = mp->m_sb_bp->b_addr;
1326 xfs_sb_to_disk(dsb, &mp->m_sb);
1327 dsb->sb_features_log_incompat |= cpu_to_be32(feature);
1328 error = xfs_bwrite(mp->m_sb_bp);
1329 if (error)
1330 goto shutdown;
1331
1332 /*
1333 * Add the feature bits to the incore superblock before we unlock the
1334 * buffer.
1335 */
1336 xfs_sb_add_incompat_log_features(&mp->m_sb, feature);
1337 xfs_buf_relse(mp->m_sb_bp);
1338
1339 /* Log the superblock to disk. */
1340 return xfs_sync_sb(mp, false);
1341shutdown:
1342 xfs_force_shutdown(mp, SHUTDOWN_META_IO_ERROR);
1343rele:
1344 xfs_buf_relse(mp->m_sb_bp);
1345 return error;
1346}
1347
1348/*
1349 * Clear all the log incompat flags from the superblock.
1350 *
1351 * The caller cannot be in a transaction, must ensure that the log does not
1352 * contain any log items protected by any log incompat bit, and must ensure
1353 * that there are no other threads that depend on the state of the log incompat
1354 * feature flags in the primary super.
1355 *
1356 * Returns true if the superblock is dirty.
1357 */
1358bool
1359xfs_clear_incompat_log_features(
1360 struct xfs_mount *mp)
1361{
1362 bool ret = false;
1363
1364 if (!xfs_has_crc(mp) ||
1365 !xfs_sb_has_incompat_log_feature(&mp->m_sb,
1366 XFS_SB_FEAT_INCOMPAT_LOG_ALL) ||
1367 xfs_is_shutdown(mp))
1368 return false;
1369
1370 /*
1371 * Update the incore superblock. We synchronize on the primary super
1372 * buffer lock to be consistent with the add function, though at least
1373 * in theory this shouldn't be necessary.
1374 */
1375 xfs_buf_lock(mp->m_sb_bp);
1376 xfs_buf_hold(mp->m_sb_bp);
1377
1378 if (xfs_sb_has_incompat_log_feature(&mp->m_sb,
1379 XFS_SB_FEAT_INCOMPAT_LOG_ALL)) {
1380 xfs_sb_remove_incompat_log_features(&mp->m_sb);
1381 ret = true;
1382 }
1383
1384 xfs_buf_relse(mp->m_sb_bp);
1385 return ret;
1386}
1387
1388/*
1389 * Update the in-core delayed block counter.
1390 *
1391 * We prefer to update the counter without having to take a spinlock for every
1392 * counter update (i.e. batching). Each change to delayed allocation
1393 * reservations can change can easily exceed the default percpu counter
1394 * batching, so we use a larger batch factor here.
1395 *
1396 * Note that we don't currently have any callers requiring fast summation
1397 * (e.g. percpu_counter_read) so we can use a big batch value here.
1398 */
1399#define XFS_DELALLOC_BATCH (4096)
1400void
1401xfs_mod_delalloc(
1402 struct xfs_mount *mp,
1403 int64_t delta)
1404{
1405 percpu_counter_add_batch(&mp->m_delalloc_blks, delta,
1406 XFS_DELALLOC_BATCH);
1407}
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}