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_sb.h"
13 #include "xfs_mount.h"
14 #include "xfs_trans.h"
15 #include "xfs_error.h"
16 #include "xfs_alloc.h"
17 #include "xfs_fsops.h"
18 #include "xfs_trans_space.h"
19 #include "xfs_log.h"
20 #include "xfs_ag.h"
21 #include "xfs_ag_resv.h"
22
23 /*
24 * growfs operations
25 */
26 static int
xfs_growfs_data_private(xfs_mount_t * mp,xfs_growfs_data_t * in)27 xfs_growfs_data_private(
28 xfs_mount_t *mp, /* mount point for filesystem */
29 xfs_growfs_data_t *in) /* growfs data input struct */
30 {
31 xfs_buf_t *bp;
32 int error;
33 xfs_agnumber_t nagcount;
34 xfs_agnumber_t nagimax = 0;
35 xfs_rfsblock_t nb, nb_mod;
36 xfs_rfsblock_t new;
37 xfs_agnumber_t oagcount;
38 xfs_trans_t *tp;
39 struct aghdr_init_data id = {};
40
41 nb = in->newblocks;
42 if (nb < mp->m_sb.sb_dblocks)
43 return -EINVAL;
44 if ((error = xfs_sb_validate_fsb_count(&mp->m_sb, nb)))
45 return error;
46 error = xfs_buf_read_uncached(mp->m_ddev_targp,
47 XFS_FSB_TO_BB(mp, nb) - XFS_FSS_TO_BB(mp, 1),
48 XFS_FSS_TO_BB(mp, 1), 0, &bp, NULL);
49 if (error)
50 return error;
51 xfs_buf_relse(bp);
52
53 new = nb; /* use new as a temporary here */
54 nb_mod = do_div(new, mp->m_sb.sb_agblocks);
55 nagcount = new + (nb_mod != 0);
56 if (nb_mod && nb_mod < XFS_MIN_AG_BLOCKS) {
57 nagcount--;
58 nb = (xfs_rfsblock_t)nagcount * mp->m_sb.sb_agblocks;
59 if (nb < mp->m_sb.sb_dblocks)
60 return -EINVAL;
61 }
62 new = nb - mp->m_sb.sb_dblocks;
63 oagcount = mp->m_sb.sb_agcount;
64
65 /* allocate the new per-ag structures */
66 if (nagcount > oagcount) {
67 error = xfs_initialize_perag(mp, nagcount, &nagimax);
68 if (error)
69 return error;
70 }
71
72 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growdata,
73 XFS_GROWFS_SPACE_RES(mp), 0, XFS_TRANS_RESERVE, &tp);
74 if (error)
75 return error;
76
77 /*
78 * Write new AG headers to disk. Non-transactional, but need to be
79 * written and completed prior to the growfs transaction being logged.
80 * To do this, we use a delayed write buffer list and wait for
81 * submission and IO completion of the list as a whole. This allows the
82 * IO subsystem to merge all the AG headers in a single AG into a single
83 * IO and hide most of the latency of the IO from us.
84 *
85 * This also means that if we get an error whilst building the buffer
86 * list to write, we can cancel the entire list without having written
87 * anything.
88 */
89 INIT_LIST_HEAD(&id.buffer_list);
90 for (id.agno = nagcount - 1;
91 id.agno >= oagcount;
92 id.agno--, new -= id.agsize) {
93
94 if (id.agno == nagcount - 1)
95 id.agsize = nb -
96 (id.agno * (xfs_rfsblock_t)mp->m_sb.sb_agblocks);
97 else
98 id.agsize = mp->m_sb.sb_agblocks;
99
100 error = xfs_ag_init_headers(mp, &id);
101 if (error) {
102 xfs_buf_delwri_cancel(&id.buffer_list);
103 goto out_trans_cancel;
104 }
105 }
106 error = xfs_buf_delwri_submit(&id.buffer_list);
107 if (error)
108 goto out_trans_cancel;
109
110 xfs_trans_agblocks_delta(tp, id.nfree);
111
112 /* If there are new blocks in the old last AG, extend it. */
113 if (new) {
114 error = xfs_ag_extend_space(mp, tp, &id, new);
115 if (error)
116 goto out_trans_cancel;
117 }
118
119 /*
120 * Update changed superblock fields transactionally. These are not
121 * seen by the rest of the world until the transaction commit applies
122 * them atomically to the superblock.
123 */
124 if (nagcount > oagcount)
125 xfs_trans_mod_sb(tp, XFS_TRANS_SB_AGCOUNT, nagcount - oagcount);
126 if (nb > mp->m_sb.sb_dblocks)
127 xfs_trans_mod_sb(tp, XFS_TRANS_SB_DBLOCKS,
128 nb - mp->m_sb.sb_dblocks);
129 if (id.nfree)
130 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, id.nfree);
131 xfs_trans_set_sync(tp);
132 error = xfs_trans_commit(tp);
133 if (error)
134 return error;
135
136 /* New allocation groups fully initialized, so update mount struct */
137 if (nagimax)
138 mp->m_maxagi = nagimax;
139 xfs_set_low_space_thresholds(mp);
140 mp->m_alloc_set_aside = xfs_alloc_set_aside(mp);
141
142 /*
143 * If we expanded the last AG, free the per-AG reservation
144 * so we can reinitialize it with the new size.
145 */
146 if (new) {
147 struct xfs_perag *pag;
148
149 pag = xfs_perag_get(mp, id.agno);
150 error = xfs_ag_resv_free(pag);
151 xfs_perag_put(pag);
152 if (error)
153 return error;
154 }
155
156 /*
157 * Reserve AG metadata blocks. ENOSPC here does not mean there was a
158 * growfs failure, just that there still isn't space for new user data
159 * after the grow has been run.
160 */
161 error = xfs_fs_reserve_ag_blocks(mp);
162 if (error == -ENOSPC)
163 error = 0;
164 return error;
165
166 out_trans_cancel:
167 xfs_trans_cancel(tp);
168 return error;
169 }
170
171 static int
xfs_growfs_log_private(xfs_mount_t * mp,xfs_growfs_log_t * in)172 xfs_growfs_log_private(
173 xfs_mount_t *mp, /* mount point for filesystem */
174 xfs_growfs_log_t *in) /* growfs log input struct */
175 {
176 xfs_extlen_t nb;
177
178 nb = in->newblocks;
179 if (nb < XFS_MIN_LOG_BLOCKS || nb < XFS_B_TO_FSB(mp, XFS_MIN_LOG_BYTES))
180 return -EINVAL;
181 if (nb == mp->m_sb.sb_logblocks &&
182 in->isint == (mp->m_sb.sb_logstart != 0))
183 return -EINVAL;
184 /*
185 * Moving the log is hard, need new interfaces to sync
186 * the log first, hold off all activity while moving it.
187 * Can have shorter or longer log in the same space,
188 * or transform internal to external log or vice versa.
189 */
190 return -ENOSYS;
191 }
192
193 static int
xfs_growfs_imaxpct(struct xfs_mount * mp,__u32 imaxpct)194 xfs_growfs_imaxpct(
195 struct xfs_mount *mp,
196 __u32 imaxpct)
197 {
198 struct xfs_trans *tp;
199 int dpct;
200 int error;
201
202 if (imaxpct > 100)
203 return -EINVAL;
204
205 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growdata,
206 XFS_GROWFS_SPACE_RES(mp), 0, XFS_TRANS_RESERVE, &tp);
207 if (error)
208 return error;
209
210 dpct = imaxpct - mp->m_sb.sb_imax_pct;
211 xfs_trans_mod_sb(tp, XFS_TRANS_SB_IMAXPCT, dpct);
212 xfs_trans_set_sync(tp);
213 return xfs_trans_commit(tp);
214 }
215
216 /*
217 * protected versions of growfs function acquire and release locks on the mount
218 * point - exported through ioctls: XFS_IOC_FSGROWFSDATA, XFS_IOC_FSGROWFSLOG,
219 * XFS_IOC_FSGROWFSRT
220 */
221 int
xfs_growfs_data(struct xfs_mount * mp,struct xfs_growfs_data * in)222 xfs_growfs_data(
223 struct xfs_mount *mp,
224 struct xfs_growfs_data *in)
225 {
226 int error = 0;
227
228 if (!capable(CAP_SYS_ADMIN))
229 return -EPERM;
230 if (!mutex_trylock(&mp->m_growlock))
231 return -EWOULDBLOCK;
232
233 /* update imaxpct separately to the physical grow of the filesystem */
234 if (in->imaxpct != mp->m_sb.sb_imax_pct) {
235 error = xfs_growfs_imaxpct(mp, in->imaxpct);
236 if (error)
237 goto out_error;
238 }
239
240 if (in->newblocks != mp->m_sb.sb_dblocks) {
241 error = xfs_growfs_data_private(mp, in);
242 if (error)
243 goto out_error;
244 }
245
246 /* Post growfs calculations needed to reflect new state in operations */
247 if (mp->m_sb.sb_imax_pct) {
248 uint64_t icount = mp->m_sb.sb_dblocks * mp->m_sb.sb_imax_pct;
249 do_div(icount, 100);
250 M_IGEO(mp)->maxicount = XFS_FSB_TO_INO(mp, icount);
251 } else
252 M_IGEO(mp)->maxicount = 0;
253
254 /* Update secondary superblocks now the physical grow has completed */
255 error = xfs_update_secondary_sbs(mp);
256
257 out_error:
258 /*
259 * Increment the generation unconditionally, the error could be from
260 * updating the secondary superblocks, in which case the new size
261 * is live already.
262 */
263 mp->m_generation++;
264 mutex_unlock(&mp->m_growlock);
265 return error;
266 }
267
268 int
xfs_growfs_log(xfs_mount_t * mp,xfs_growfs_log_t * in)269 xfs_growfs_log(
270 xfs_mount_t *mp,
271 xfs_growfs_log_t *in)
272 {
273 int error;
274
275 if (!capable(CAP_SYS_ADMIN))
276 return -EPERM;
277 if (!mutex_trylock(&mp->m_growlock))
278 return -EWOULDBLOCK;
279 error = xfs_growfs_log_private(mp, in);
280 mutex_unlock(&mp->m_growlock);
281 return error;
282 }
283
284 /*
285 * exported through ioctl XFS_IOC_FSCOUNTS
286 */
287
288 void
xfs_fs_counts(xfs_mount_t * mp,xfs_fsop_counts_t * cnt)289 xfs_fs_counts(
290 xfs_mount_t *mp,
291 xfs_fsop_counts_t *cnt)
292 {
293 cnt->allocino = percpu_counter_read_positive(&mp->m_icount);
294 cnt->freeino = percpu_counter_read_positive(&mp->m_ifree);
295 cnt->freedata = percpu_counter_read_positive(&mp->m_fdblocks) -
296 mp->m_alloc_set_aside;
297
298 spin_lock(&mp->m_sb_lock);
299 cnt->freertx = mp->m_sb.sb_frextents;
300 spin_unlock(&mp->m_sb_lock);
301 }
302
303 /*
304 * exported through ioctl XFS_IOC_SET_RESBLKS & XFS_IOC_GET_RESBLKS
305 *
306 * xfs_reserve_blocks is called to set m_resblks
307 * in the in-core mount table. The number of unused reserved blocks
308 * is kept in m_resblks_avail.
309 *
310 * Reserve the requested number of blocks if available. Otherwise return
311 * as many as possible to satisfy the request. The actual number
312 * reserved are returned in outval
313 *
314 * A null inval pointer indicates that only the current reserved blocks
315 * available should be returned no settings are changed.
316 */
317
318 int
xfs_reserve_blocks(xfs_mount_t * mp,uint64_t * inval,xfs_fsop_resblks_t * outval)319 xfs_reserve_blocks(
320 xfs_mount_t *mp,
321 uint64_t *inval,
322 xfs_fsop_resblks_t *outval)
323 {
324 int64_t lcounter, delta;
325 int64_t fdblks_delta = 0;
326 uint64_t request;
327 int64_t free;
328 int error = 0;
329
330 /* If inval is null, report current values and return */
331 if (inval == (uint64_t *)NULL) {
332 if (!outval)
333 return -EINVAL;
334 outval->resblks = mp->m_resblks;
335 outval->resblks_avail = mp->m_resblks_avail;
336 return 0;
337 }
338
339 request = *inval;
340
341 /*
342 * With per-cpu counters, this becomes an interesting problem. we need
343 * to work out if we are freeing or allocation blocks first, then we can
344 * do the modification as necessary.
345 *
346 * We do this under the m_sb_lock so that if we are near ENOSPC, we will
347 * hold out any changes while we work out what to do. This means that
348 * the amount of free space can change while we do this, so we need to
349 * retry if we end up trying to reserve more space than is available.
350 */
351 spin_lock(&mp->m_sb_lock);
352
353 /*
354 * If our previous reservation was larger than the current value,
355 * then move any unused blocks back to the free pool. Modify the resblks
356 * counters directly since we shouldn't have any problems unreserving
357 * space.
358 */
359 if (mp->m_resblks > request) {
360 lcounter = mp->m_resblks_avail - request;
361 if (lcounter > 0) { /* release unused blocks */
362 fdblks_delta = lcounter;
363 mp->m_resblks_avail -= lcounter;
364 }
365 mp->m_resblks = request;
366 if (fdblks_delta) {
367 spin_unlock(&mp->m_sb_lock);
368 error = xfs_mod_fdblocks(mp, fdblks_delta, 0);
369 spin_lock(&mp->m_sb_lock);
370 }
371
372 goto out;
373 }
374
375 /*
376 * If the request is larger than the current reservation, reserve the
377 * blocks before we update the reserve counters. Sample m_fdblocks and
378 * perform a partial reservation if the request exceeds free space.
379 *
380 * The code below estimates how many blocks it can request from
381 * fdblocks to stash in the reserve pool. This is a classic TOCTOU
382 * race since fdblocks updates are not always coordinated via
383 * m_sb_lock. Set the reserve size even if there's not enough free
384 * space to fill it because mod_fdblocks will refill an undersized
385 * reserve when it can.
386 */
387 free = percpu_counter_sum(&mp->m_fdblocks) -
388 xfs_fdblocks_unavailable(mp);
389 delta = request - mp->m_resblks;
390 mp->m_resblks = request;
391 if (delta > 0 && free > 0) {
392 /*
393 * We'll either succeed in getting space from the free block
394 * count or we'll get an ENOSPC. Don't set the reserved flag
395 * here - we don't want to reserve the extra reserve blocks
396 * from the reserve.
397 *
398 * The desired reserve size can change after we drop the lock.
399 * Use mod_fdblocks to put the space into the reserve or into
400 * fdblocks as appropriate.
401 */
402 fdblks_delta = min(free, delta);
403 spin_unlock(&mp->m_sb_lock);
404 error = xfs_mod_fdblocks(mp, -fdblks_delta, 0);
405 if (!error)
406 xfs_mod_fdblocks(mp, fdblks_delta, 0);
407 spin_lock(&mp->m_sb_lock);
408 }
409 out:
410 if (outval) {
411 outval->resblks = mp->m_resblks;
412 outval->resblks_avail = mp->m_resblks_avail;
413 }
414
415 spin_unlock(&mp->m_sb_lock);
416 return error;
417 }
418
419 int
xfs_fs_goingdown(xfs_mount_t * mp,uint32_t inflags)420 xfs_fs_goingdown(
421 xfs_mount_t *mp,
422 uint32_t inflags)
423 {
424 switch (inflags) {
425 case XFS_FSOP_GOING_FLAGS_DEFAULT: {
426 struct super_block *sb = freeze_bdev(mp->m_super->s_bdev);
427
428 if (sb && !IS_ERR(sb)) {
429 xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
430 thaw_bdev(sb->s_bdev, sb);
431 }
432
433 break;
434 }
435 case XFS_FSOP_GOING_FLAGS_LOGFLUSH:
436 xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
437 break;
438 case XFS_FSOP_GOING_FLAGS_NOLOGFLUSH:
439 xfs_force_shutdown(mp,
440 SHUTDOWN_FORCE_UMOUNT | SHUTDOWN_LOG_IO_ERROR);
441 break;
442 default:
443 return -EINVAL;
444 }
445
446 return 0;
447 }
448
449 /*
450 * Force a shutdown of the filesystem instantly while keeping the filesystem
451 * consistent. We don't do an unmount here; just shutdown the shop, make sure
452 * that absolutely nothing persistent happens to this filesystem after this
453 * point.
454 */
455 void
xfs_do_force_shutdown(struct xfs_mount * mp,int flags,char * fname,int lnnum)456 xfs_do_force_shutdown(
457 struct xfs_mount *mp,
458 int flags,
459 char *fname,
460 int lnnum)
461 {
462 bool logerror = flags & SHUTDOWN_LOG_IO_ERROR;
463
464 /*
465 * No need to duplicate efforts.
466 */
467 if (XFS_FORCED_SHUTDOWN(mp) && !logerror)
468 return;
469
470 /*
471 * This flags XFS_MOUNT_FS_SHUTDOWN, makes sure that we don't
472 * queue up anybody new on the log reservations, and wakes up
473 * everybody who's sleeping on log reservations to tell them
474 * the bad news.
475 */
476 if (xfs_log_force_umount(mp, logerror))
477 return;
478
479 if (flags & SHUTDOWN_FORCE_UMOUNT) {
480 xfs_alert(mp,
481 "User initiated shutdown received. Shutting down filesystem");
482 return;
483 }
484
485 xfs_notice(mp,
486 "%s(0x%x) called from line %d of file %s. Return address = "PTR_FMT,
487 __func__, flags, lnnum, fname, __return_address);
488
489 if (flags & SHUTDOWN_CORRUPT_INCORE) {
490 xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_CORRUPT,
491 "Corruption of in-memory data detected. Shutting down filesystem");
492 if (XFS_ERRLEVEL_HIGH <= xfs_error_level)
493 xfs_stack_trace();
494 } else if (logerror) {
495 xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_LOGERROR,
496 "Log I/O Error Detected. Shutting down filesystem");
497 } else {
498 xfs_alert_tag(mp, XFS_PTAG_SHUTDOWN_IOERROR,
499 "I/O Error Detected. Shutting down filesystem");
500 }
501
502 xfs_alert(mp,
503 "Please unmount the filesystem and rectify the problem(s)");
504 }
505
506 /*
507 * Reserve free space for per-AG metadata.
508 */
509 int
xfs_fs_reserve_ag_blocks(struct xfs_mount * mp)510 xfs_fs_reserve_ag_blocks(
511 struct xfs_mount *mp)
512 {
513 xfs_agnumber_t agno;
514 struct xfs_perag *pag;
515 int error = 0;
516 int err2;
517
518 mp->m_finobt_nores = false;
519 for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
520 pag = xfs_perag_get(mp, agno);
521 err2 = xfs_ag_resv_init(pag, NULL);
522 xfs_perag_put(pag);
523 if (err2 && !error)
524 error = err2;
525 }
526
527 if (error && error != -ENOSPC) {
528 xfs_warn(mp,
529 "Error %d reserving per-AG metadata reserve pool.", error);
530 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
531 }
532
533 return error;
534 }
535
536 /*
537 * Free space reserved for per-AG metadata.
538 */
539 int
xfs_fs_unreserve_ag_blocks(struct xfs_mount * mp)540 xfs_fs_unreserve_ag_blocks(
541 struct xfs_mount *mp)
542 {
543 xfs_agnumber_t agno;
544 struct xfs_perag *pag;
545 int error = 0;
546 int err2;
547
548 for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
549 pag = xfs_perag_get(mp, agno);
550 err2 = xfs_ag_resv_free(pag);
551 xfs_perag_put(pag);
552 if (err2 && !error)
553 error = err2;
554 }
555
556 if (error)
557 xfs_warn(mp,
558 "Error %d freeing per-AG metadata reserve pool.", error);
559
560 return error;
561 }
562