1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2000-2003 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6#include "xfs.h"
7#include "xfs_fs.h"
8#include "xfs_format.h"
9#include "xfs_log_format.h"
10#include "xfs_shared.h"
11#include "xfs_trans_resv.h"
12#include "xfs_bit.h"
13#include "xfs_mount.h"
14#include "xfs_defer.h"
15#include "xfs_inode.h"
16#include "xfs_bmap.h"
17#include "xfs_quota.h"
18#include "xfs_trans.h"
19#include "xfs_buf_item.h"
20#include "xfs_trans_space.h"
21#include "xfs_trans_priv.h"
22#include "xfs_qm.h"
23#include "xfs_trace.h"
24#include "xfs_log.h"
25#include "xfs_bmap_btree.h"
26#include "xfs_error.h"
27#include "xfs_health.h"
28
29/*
30 * Lock order:
31 *
32 * ip->i_lock
33 * qi->qi_tree_lock
34 * dquot->q_qlock (xfs_dqlock() and friends)
35 * dquot->q_flush (xfs_dqflock() and friends)
36 * qi->qi_lru_lock
37 *
38 * If two dquots need to be locked the order is user before group/project,
39 * otherwise by the lowest id first, see xfs_dqlock2.
40 */
41
42struct kmem_cache *xfs_dqtrx_cache;
43static struct kmem_cache *xfs_dquot_cache;
44
45static struct lock_class_key xfs_dquot_group_class;
46static struct lock_class_key xfs_dquot_project_class;
47
48/* Record observations of quota corruption with the health tracking system. */
49static void
50xfs_dquot_mark_sick(
51 struct xfs_dquot *dqp)
52{
53 struct xfs_mount *mp = dqp->q_mount;
54
55 switch (dqp->q_type) {
56 case XFS_DQTYPE_USER:
57 xfs_fs_mark_sick(mp, XFS_SICK_FS_UQUOTA);
58 break;
59 case XFS_DQTYPE_GROUP:
60 xfs_fs_mark_sick(mp, XFS_SICK_FS_GQUOTA);
61 break;
62 case XFS_DQTYPE_PROJ:
63 xfs_fs_mark_sick(mp, XFS_SICK_FS_PQUOTA);
64 break;
65 default:
66 ASSERT(0);
67 break;
68 }
69}
70
71/*
72 * This is called to free all the memory associated with a dquot
73 */
74void
75xfs_qm_dqdestroy(
76 struct xfs_dquot *dqp)
77{
78 ASSERT(list_empty(&dqp->q_lru));
79
80 kvfree(addr: dqp->q_logitem.qli_item.li_lv_shadow);
81 mutex_destroy(lock: &dqp->q_qlock);
82
83 XFS_STATS_DEC(dqp->q_mount, xs_qm_dquot);
84 kmem_cache_free(s: xfs_dquot_cache, objp: dqp);
85}
86
87/*
88 * If default limits are in force, push them into the dquot now.
89 * We overwrite the dquot limits only if they are zero and this
90 * is not the root dquot.
91 */
92void
93xfs_qm_adjust_dqlimits(
94 struct xfs_dquot *dq)
95{
96 struct xfs_mount *mp = dq->q_mount;
97 struct xfs_quotainfo *q = mp->m_quotainfo;
98 struct xfs_def_quota *defq;
99 int prealloc = 0;
100
101 ASSERT(dq->q_id);
102 defq = xfs_get_defquota(q, xfs_dquot_type(dqp: dq));
103
104 if (!dq->q_blk.softlimit) {
105 dq->q_blk.softlimit = defq->blk.soft;
106 prealloc = 1;
107 }
108 if (!dq->q_blk.hardlimit) {
109 dq->q_blk.hardlimit = defq->blk.hard;
110 prealloc = 1;
111 }
112 if (!dq->q_ino.softlimit)
113 dq->q_ino.softlimit = defq->ino.soft;
114 if (!dq->q_ino.hardlimit)
115 dq->q_ino.hardlimit = defq->ino.hard;
116 if (!dq->q_rtb.softlimit)
117 dq->q_rtb.softlimit = defq->rtb.soft;
118 if (!dq->q_rtb.hardlimit)
119 dq->q_rtb.hardlimit = defq->rtb.hard;
120
121 if (prealloc)
122 xfs_dquot_set_prealloc_limits(dq);
123}
124
125/* Set the expiration time of a quota's grace period. */
126time64_t
127xfs_dquot_set_timeout(
128 struct xfs_mount *mp,
129 time64_t timeout)
130{
131 struct xfs_quotainfo *qi = mp->m_quotainfo;
132
133 return clamp_t(time64_t, timeout, qi->qi_expiry_min,
134 qi->qi_expiry_max);
135}
136
137/* Set the length of the default grace period. */
138time64_t
139xfs_dquot_set_grace_period(
140 time64_t grace)
141{
142 return clamp_t(time64_t, grace, XFS_DQ_GRACE_MIN, XFS_DQ_GRACE_MAX);
143}
144
145/*
146 * Determine if this quota counter is over either limit and set the quota
147 * timers as appropriate.
148 */
149static inline void
150xfs_qm_adjust_res_timer(
151 struct xfs_mount *mp,
152 struct xfs_dquot_res *res,
153 struct xfs_quota_limits *qlim)
154{
155 ASSERT(res->hardlimit == 0 || res->softlimit <= res->hardlimit);
156
157 if ((res->softlimit && res->count > res->softlimit) ||
158 (res->hardlimit && res->count > res->hardlimit)) {
159 if (res->timer == 0)
160 res->timer = xfs_dquot_set_timeout(mp,
161 timeout: ktime_get_real_seconds() + qlim->time);
162 } else {
163 res->timer = 0;
164 }
165}
166
167/*
168 * Check the limits and timers of a dquot and start or reset timers
169 * if necessary.
170 * This gets called even when quota enforcement is OFF, which makes our
171 * life a little less complicated. (We just don't reject any quota
172 * reservations in that case, when enforcement is off).
173 * We also return 0 as the values of the timers in Q_GETQUOTA calls, when
174 * enforcement's off.
175 * In contrast, warnings are a little different in that they don't
176 * 'automatically' get started when limits get exceeded. They do
177 * get reset to zero, however, when we find the count to be under
178 * the soft limit (they are only ever set non-zero via userspace).
179 */
180void
181xfs_qm_adjust_dqtimers(
182 struct xfs_dquot *dq)
183{
184 struct xfs_mount *mp = dq->q_mount;
185 struct xfs_quotainfo *qi = mp->m_quotainfo;
186 struct xfs_def_quota *defq;
187
188 ASSERT(dq->q_id);
189 defq = xfs_get_defquota(qi, xfs_dquot_type(dqp: dq));
190
191 xfs_qm_adjust_res_timer(mp: dq->q_mount, res: &dq->q_blk, qlim: &defq->blk);
192 xfs_qm_adjust_res_timer(mp: dq->q_mount, res: &dq->q_ino, qlim: &defq->ino);
193 xfs_qm_adjust_res_timer(mp: dq->q_mount, res: &dq->q_rtb, qlim: &defq->rtb);
194}
195
196/*
197 * initialize a buffer full of dquots and log the whole thing
198 */
199void
200xfs_qm_init_dquot_blk(
201 struct xfs_trans *tp,
202 xfs_dqid_t id,
203 xfs_dqtype_t type,
204 struct xfs_buf *bp)
205{
206 struct xfs_mount *mp = tp->t_mountp;
207 struct xfs_quotainfo *q = mp->m_quotainfo;
208 struct xfs_dqblk *d;
209 xfs_dqid_t curid;
210 unsigned int qflag;
211 unsigned int blftype;
212 int i;
213
214 ASSERT(tp);
215 ASSERT(xfs_buf_islocked(bp));
216
217 switch (type) {
218 case XFS_DQTYPE_USER:
219 qflag = XFS_UQUOTA_CHKD;
220 blftype = XFS_BLF_UDQUOT_BUF;
221 break;
222 case XFS_DQTYPE_PROJ:
223 qflag = XFS_PQUOTA_CHKD;
224 blftype = XFS_BLF_PDQUOT_BUF;
225 break;
226 case XFS_DQTYPE_GROUP:
227 qflag = XFS_GQUOTA_CHKD;
228 blftype = XFS_BLF_GDQUOT_BUF;
229 break;
230 default:
231 ASSERT(0);
232 return;
233 }
234
235 d = bp->b_addr;
236
237 /*
238 * ID of the first dquot in the block - id's are zero based.
239 */
240 curid = id - (id % q->qi_dqperchunk);
241 memset(d, 0, BBTOB(q->qi_dqchunklen));
242 for (i = 0; i < q->qi_dqperchunk; i++, d++, curid++) {
243 d->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
244 d->dd_diskdq.d_version = XFS_DQUOT_VERSION;
245 d->dd_diskdq.d_id = cpu_to_be32(curid);
246 d->dd_diskdq.d_type = type;
247 if (curid > 0 && xfs_has_bigtime(mp))
248 d->dd_diskdq.d_type |= XFS_DQTYPE_BIGTIME;
249 if (xfs_has_crc(mp)) {
250 uuid_copy(dst: &d->dd_uuid, src: &mp->m_sb.sb_meta_uuid);
251 xfs_update_cksum((char *)d, sizeof(struct xfs_dqblk),
252 XFS_DQUOT_CRC_OFF);
253 }
254 }
255
256 xfs_trans_dquot_buf(tp, bp, blftype);
257
258 /*
259 * quotacheck uses delayed writes to update all the dquots on disk in an
260 * efficient manner instead of logging the individual dquot changes as
261 * they are made. However if we log the buffer allocated here and crash
262 * after quotacheck while the logged initialisation is still in the
263 * active region of the log, log recovery can replay the dquot buffer
264 * initialisation over the top of the checked dquots and corrupt quota
265 * accounting.
266 *
267 * To avoid this problem, quotacheck cannot log the initialised buffer.
268 * We must still dirty the buffer and write it back before the
269 * allocation transaction clears the log. Therefore, mark the buffer as
270 * ordered instead of logging it directly. This is safe for quotacheck
271 * because it detects and repairs allocated but initialized dquot blocks
272 * in the quota inodes.
273 */
274 if (!(mp->m_qflags & qflag))
275 xfs_trans_ordered_buf(tp, bp);
276 else
277 xfs_trans_log_buf(tp, bp, 0, BBTOB(q->qi_dqchunklen) - 1);
278}
279
280/*
281 * Initialize the dynamic speculative preallocation thresholds. The lo/hi
282 * watermarks correspond to the soft and hard limits by default. If a soft limit
283 * is not specified, we use 95% of the hard limit.
284 */
285void
286xfs_dquot_set_prealloc_limits(struct xfs_dquot *dqp)
287{
288 uint64_t space;
289
290 dqp->q_prealloc_hi_wmark = dqp->q_blk.hardlimit;
291 dqp->q_prealloc_lo_wmark = dqp->q_blk.softlimit;
292 if (!dqp->q_prealloc_lo_wmark) {
293 dqp->q_prealloc_lo_wmark = dqp->q_prealloc_hi_wmark;
294 do_div(dqp->q_prealloc_lo_wmark, 100);
295 dqp->q_prealloc_lo_wmark *= 95;
296 }
297
298 space = dqp->q_prealloc_hi_wmark;
299
300 do_div(space, 100);
301 dqp->q_low_space[XFS_QLOWSP_1_PCNT] = space;
302 dqp->q_low_space[XFS_QLOWSP_3_PCNT] = space * 3;
303 dqp->q_low_space[XFS_QLOWSP_5_PCNT] = space * 5;
304}
305
306/*
307 * Ensure that the given in-core dquot has a buffer on disk backing it, and
308 * return the buffer locked and held. This is called when the bmapi finds a
309 * hole.
310 */
311STATIC int
312xfs_dquot_disk_alloc(
313 struct xfs_dquot *dqp,
314 struct xfs_buf **bpp)
315{
316 struct xfs_bmbt_irec map;
317 struct xfs_trans *tp;
318 struct xfs_mount *mp = dqp->q_mount;
319 struct xfs_buf *bp;
320 xfs_dqtype_t qtype = xfs_dquot_type(dqp);
321 struct xfs_inode *quotip = xfs_quota_inode(mp, qtype);
322 int nmaps = 1;
323 int error;
324
325 trace_xfs_dqalloc(dqp);
326
327 error = xfs_trans_alloc(mp, resp: &M_RES(mp)->tr_qm_dqalloc,
328 blocks: XFS_QM_DQALLOC_SPACE_RES(mp), rtextents: 0, flags: 0, tpp: &tp);
329 if (error)
330 return error;
331
332 xfs_ilock(quotip, XFS_ILOCK_EXCL);
333 xfs_trans_ijoin(tp, quotip, 0);
334
335 if (!xfs_this_quota_on(dqp->q_mount, qtype)) {
336 /*
337 * Return if this type of quotas is turned off while we didn't
338 * have an inode lock
339 */
340 error = -ESRCH;
341 goto err_cancel;
342 }
343
344 error = xfs_iext_count_may_overflow(quotip, XFS_DATA_FORK,
345 XFS_IEXT_ADD_NOSPLIT_CNT);
346 if (error == -EFBIG)
347 error = xfs_iext_count_upgrade(tp, quotip,
348 XFS_IEXT_ADD_NOSPLIT_CNT);
349 if (error)
350 goto err_cancel;
351
352 /* Create the block mapping. */
353 error = xfs_bmapi_write(tp, quotip, dqp->q_fileoffset,
354 XFS_DQUOT_CLUSTER_SIZE_FSB, XFS_BMAPI_METADATA, 0, &map,
355 &nmaps);
356 if (error)
357 goto err_cancel;
358
359 ASSERT(map.br_blockcount == XFS_DQUOT_CLUSTER_SIZE_FSB);
360 ASSERT(nmaps == 1);
361 ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&
362 (map.br_startblock != HOLESTARTBLOCK));
363
364 /*
365 * Keep track of the blkno to save a lookup later
366 */
367 dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock);
368
369 /* now we can just get the buffer (there's nothing to read yet) */
370 error = xfs_trans_get_buf(tp, target: mp->m_ddev_targp, blkno: dqp->q_blkno,
371 numblks: mp->m_quotainfo->qi_dqchunklen, flags: 0, bpp: &bp);
372 if (error)
373 goto err_cancel;
374 bp->b_ops = &xfs_dquot_buf_ops;
375
376 /*
377 * Make a chunk of dquots out of this buffer and log
378 * the entire thing.
379 */
380 xfs_qm_init_dquot_blk(tp, dqp->q_id, qtype, bp);
381 xfs_buf_set_ref(bp, XFS_DQUOT_REF);
382
383 /*
384 * Hold the buffer and join it to the dfops so that we'll still own
385 * the buffer when we return to the caller. The buffer disposal on
386 * error must be paid attention to very carefully, as it has been
387 * broken since commit efa092f3d4c6 "[XFS] Fixes a bug in the quota
388 * code when allocating a new dquot record" in 2005, and the later
389 * conversion to xfs_defer_ops in commit 310a75a3c6c747 failed to keep
390 * the buffer locked across the _defer_finish call. We can now do
391 * this correctly with xfs_defer_bjoin.
392 *
393 * Above, we allocated a disk block for the dquot information and used
394 * get_buf to initialize the dquot. If the _defer_finish fails, the old
395 * transaction is gone but the new buffer is not joined or held to any
396 * transaction, so we must _buf_relse it.
397 *
398 * If everything succeeds, the caller of this function is returned a
399 * buffer that is locked and held to the transaction. The caller
400 * is responsible for unlocking any buffer passed back, either
401 * manually or by committing the transaction. On error, the buffer is
402 * released and not passed back.
403 *
404 * Keep the quota inode ILOCKed until after the transaction commit to
405 * maintain the atomicity of bmap/rmap updates.
406 */
407 xfs_trans_bhold(tp, bp);
408 error = xfs_trans_commit(tp);
409 xfs_iunlock(quotip, XFS_ILOCK_EXCL);
410 if (error) {
411 xfs_buf_relse(bp);
412 return error;
413 }
414
415 *bpp = bp;
416 return 0;
417
418err_cancel:
419 xfs_trans_cancel(tp);
420 xfs_iunlock(quotip, XFS_ILOCK_EXCL);
421 return error;
422}
423
424/*
425 * Read in the in-core dquot's on-disk metadata and return the buffer.
426 * Returns ENOENT to signal a hole.
427 */
428STATIC int
429xfs_dquot_disk_read(
430 struct xfs_mount *mp,
431 struct xfs_dquot *dqp,
432 struct xfs_buf **bpp)
433{
434 struct xfs_bmbt_irec map;
435 struct xfs_buf *bp;
436 xfs_dqtype_t qtype = xfs_dquot_type(dqp);
437 struct xfs_inode *quotip = xfs_quota_inode(mp, qtype);
438 uint lock_mode;
439 int nmaps = 1;
440 int error;
441
442 lock_mode = xfs_ilock_data_map_shared(quotip);
443 if (!xfs_this_quota_on(mp, qtype)) {
444 /*
445 * Return if this type of quotas is turned off while we
446 * didn't have the quota inode lock.
447 */
448 xfs_iunlock(quotip, lock_mode);
449 return -ESRCH;
450 }
451
452 /*
453 * Find the block map; no allocations yet
454 */
455 error = xfs_bmapi_read(quotip, dqp->q_fileoffset,
456 XFS_DQUOT_CLUSTER_SIZE_FSB, &map, &nmaps, 0);
457 xfs_iunlock(quotip, lock_mode);
458 if (error)
459 return error;
460
461 ASSERT(nmaps == 1);
462 ASSERT(map.br_blockcount >= 1);
463 ASSERT(map.br_startblock != DELAYSTARTBLOCK);
464 if (map.br_startblock == HOLESTARTBLOCK)
465 return -ENOENT;
466
467 trace_xfs_dqtobp_read(dqp);
468
469 /*
470 * store the blkno etc so that we don't have to do the
471 * mapping all the time
472 */
473 dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock);
474
475 error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, dqp->q_blkno,
476 mp->m_quotainfo->qi_dqchunklen, 0, &bp,
477 &xfs_dquot_buf_ops);
478 if (xfs_metadata_is_sick(error))
479 xfs_dquot_mark_sick(dqp);
480 if (error) {
481 ASSERT(bp == NULL);
482 return error;
483 }
484
485 ASSERT(xfs_buf_islocked(bp));
486 xfs_buf_set_ref(bp, XFS_DQUOT_REF);
487 *bpp = bp;
488
489 return 0;
490}
491
492/* Allocate and initialize everything we need for an incore dquot. */
493STATIC struct xfs_dquot *
494xfs_dquot_alloc(
495 struct xfs_mount *mp,
496 xfs_dqid_t id,
497 xfs_dqtype_t type)
498{
499 struct xfs_dquot *dqp;
500
501 dqp = kmem_cache_zalloc(k: xfs_dquot_cache, GFP_KERNEL | __GFP_NOFAIL);
502
503 dqp->q_type = type;
504 dqp->q_id = id;
505 dqp->q_mount = mp;
506 INIT_LIST_HEAD(list: &dqp->q_lru);
507 mutex_init(&dqp->q_qlock);
508 init_waitqueue_head(&dqp->q_pinwait);
509 dqp->q_fileoffset = (xfs_fileoff_t)id / mp->m_quotainfo->qi_dqperchunk;
510 /*
511 * Offset of dquot in the (fixed sized) dquot chunk.
512 */
513 dqp->q_bufoffset = (id % mp->m_quotainfo->qi_dqperchunk) *
514 sizeof(struct xfs_dqblk);
515
516 /*
517 * Because we want to use a counting completion, complete
518 * the flush completion once to allow a single access to
519 * the flush completion without blocking.
520 */
521 init_completion(x: &dqp->q_flush);
522 complete(&dqp->q_flush);
523
524 /*
525 * Make sure group quotas have a different lock class than user
526 * quotas.
527 */
528 switch (type) {
529 case XFS_DQTYPE_USER:
530 /* uses the default lock class */
531 break;
532 case XFS_DQTYPE_GROUP:
533 lockdep_set_class(&dqp->q_qlock, &xfs_dquot_group_class);
534 break;
535 case XFS_DQTYPE_PROJ:
536 lockdep_set_class(&dqp->q_qlock, &xfs_dquot_project_class);
537 break;
538 default:
539 ASSERT(0);
540 break;
541 }
542
543 xfs_qm_dquot_logitem_init(dqp);
544
545 XFS_STATS_INC(mp, xs_qm_dquot);
546 return dqp;
547}
548
549/* Check the ondisk dquot's id and type match what the incore dquot expects. */
550static bool
551xfs_dquot_check_type(
552 struct xfs_dquot *dqp,
553 struct xfs_disk_dquot *ddqp)
554{
555 uint8_t ddqp_type;
556 uint8_t dqp_type;
557
558 ddqp_type = ddqp->d_type & XFS_DQTYPE_REC_MASK;
559 dqp_type = xfs_dquot_type(dqp);
560
561 if (be32_to_cpu(ddqp->d_id) != dqp->q_id)
562 return false;
563
564 /*
565 * V5 filesystems always expect an exact type match. V4 filesystems
566 * expect an exact match for user dquots and for non-root group and
567 * project dquots.
568 */
569 if (xfs_has_crc(dqp->q_mount) ||
570 dqp_type == XFS_DQTYPE_USER || dqp->q_id != 0)
571 return ddqp_type == dqp_type;
572
573 /*
574 * V4 filesystems support either group or project quotas, but not both
575 * at the same time. The non-user quota file can be switched between
576 * group and project quota uses depending on the mount options, which
577 * means that we can encounter the other type when we try to load quota
578 * defaults. Quotacheck will soon reset the entire quota file
579 * (including the root dquot) anyway, but don't log scary corruption
580 * reports to dmesg.
581 */
582 return ddqp_type == XFS_DQTYPE_GROUP || ddqp_type == XFS_DQTYPE_PROJ;
583}
584
585/* Copy the in-core quota fields in from the on-disk buffer. */
586STATIC int
587xfs_dquot_from_disk(
588 struct xfs_dquot *dqp,
589 struct xfs_buf *bp)
590{
591 struct xfs_dqblk *dqb = xfs_buf_offset(bp, dqp->q_bufoffset);
592 struct xfs_disk_dquot *ddqp = &dqb->dd_diskdq;
593
594 /*
595 * Ensure that we got the type and ID we were looking for.
596 * Everything else was checked by the dquot buffer verifier.
597 */
598 if (!xfs_dquot_check_type(dqp, ddqp)) {
599 xfs_alert_tag(bp->b_mount, XFS_PTAG_VERIFIER_ERROR,
600 "Metadata corruption detected at %pS, quota %u",
601 __this_address, dqp->q_id);
602 xfs_alert(bp->b_mount, "Unmount and run xfs_repair");
603 xfs_dquot_mark_sick(dqp);
604 return -EFSCORRUPTED;
605 }
606
607 /* copy everything from disk dquot to the incore dquot */
608 dqp->q_type = ddqp->d_type;
609 dqp->q_blk.hardlimit = be64_to_cpu(ddqp->d_blk_hardlimit);
610 dqp->q_blk.softlimit = be64_to_cpu(ddqp->d_blk_softlimit);
611 dqp->q_ino.hardlimit = be64_to_cpu(ddqp->d_ino_hardlimit);
612 dqp->q_ino.softlimit = be64_to_cpu(ddqp->d_ino_softlimit);
613 dqp->q_rtb.hardlimit = be64_to_cpu(ddqp->d_rtb_hardlimit);
614 dqp->q_rtb.softlimit = be64_to_cpu(ddqp->d_rtb_softlimit);
615
616 dqp->q_blk.count = be64_to_cpu(ddqp->d_bcount);
617 dqp->q_ino.count = be64_to_cpu(ddqp->d_icount);
618 dqp->q_rtb.count = be64_to_cpu(ddqp->d_rtbcount);
619
620 dqp->q_blk.timer = xfs_dquot_from_disk_ts(ddqp, ddqp->d_btimer);
621 dqp->q_ino.timer = xfs_dquot_from_disk_ts(ddqp, ddqp->d_itimer);
622 dqp->q_rtb.timer = xfs_dquot_from_disk_ts(ddqp, ddqp->d_rtbtimer);
623
624 /*
625 * Reservation counters are defined as reservation plus current usage
626 * to avoid having to add every time.
627 */
628 dqp->q_blk.reserved = dqp->q_blk.count;
629 dqp->q_ino.reserved = dqp->q_ino.count;
630 dqp->q_rtb.reserved = dqp->q_rtb.count;
631
632 /* initialize the dquot speculative prealloc thresholds */
633 xfs_dquot_set_prealloc_limits(dqp);
634 return 0;
635}
636
637/* Copy the in-core quota fields into the on-disk buffer. */
638void
639xfs_dquot_to_disk(
640 struct xfs_disk_dquot *ddqp,
641 struct xfs_dquot *dqp)
642{
643 ddqp->d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
644 ddqp->d_version = XFS_DQUOT_VERSION;
645 ddqp->d_type = dqp->q_type;
646 ddqp->d_id = cpu_to_be32(dqp->q_id);
647 ddqp->d_pad0 = 0;
648 ddqp->d_pad = 0;
649
650 ddqp->d_blk_hardlimit = cpu_to_be64(dqp->q_blk.hardlimit);
651 ddqp->d_blk_softlimit = cpu_to_be64(dqp->q_blk.softlimit);
652 ddqp->d_ino_hardlimit = cpu_to_be64(dqp->q_ino.hardlimit);
653 ddqp->d_ino_softlimit = cpu_to_be64(dqp->q_ino.softlimit);
654 ddqp->d_rtb_hardlimit = cpu_to_be64(dqp->q_rtb.hardlimit);
655 ddqp->d_rtb_softlimit = cpu_to_be64(dqp->q_rtb.softlimit);
656
657 ddqp->d_bcount = cpu_to_be64(dqp->q_blk.count);
658 ddqp->d_icount = cpu_to_be64(dqp->q_ino.count);
659 ddqp->d_rtbcount = cpu_to_be64(dqp->q_rtb.count);
660
661 ddqp->d_bwarns = 0;
662 ddqp->d_iwarns = 0;
663 ddqp->d_rtbwarns = 0;
664
665 ddqp->d_btimer = xfs_dquot_to_disk_ts(dqp, dqp->q_blk.timer);
666 ddqp->d_itimer = xfs_dquot_to_disk_ts(dqp, dqp->q_ino.timer);
667 ddqp->d_rtbtimer = xfs_dquot_to_disk_ts(dqp, dqp->q_rtb.timer);
668}
669
670/*
671 * Read in the ondisk dquot using dqtobp() then copy it to an incore version,
672 * and release the buffer immediately. If @can_alloc is true, fill any
673 * holes in the on-disk metadata.
674 */
675static int
676xfs_qm_dqread(
677 struct xfs_mount *mp,
678 xfs_dqid_t id,
679 xfs_dqtype_t type,
680 bool can_alloc,
681 struct xfs_dquot **dqpp)
682{
683 struct xfs_dquot *dqp;
684 struct xfs_buf *bp;
685 int error;
686
687 dqp = xfs_dquot_alloc(mp, id, type);
688 trace_xfs_dqread(dqp);
689
690 /* Try to read the buffer, allocating if necessary. */
691 error = xfs_dquot_disk_read(mp, dqp, bpp: &bp);
692 if (error == -ENOENT && can_alloc)
693 error = xfs_dquot_disk_alloc(dqp, bpp: &bp);
694 if (error)
695 goto err;
696
697 /*
698 * At this point we should have a clean locked buffer. Copy the data
699 * to the incore dquot and release the buffer since the incore dquot
700 * has its own locking protocol so we needn't tie up the buffer any
701 * further.
702 */
703 ASSERT(xfs_buf_islocked(bp));
704 error = xfs_dquot_from_disk(dqp, bp);
705 xfs_buf_relse(bp);
706 if (error)
707 goto err;
708
709 *dqpp = dqp;
710 return error;
711
712err:
713 trace_xfs_dqread_fail(dqp);
714 xfs_qm_dqdestroy(dqp);
715 *dqpp = NULL;
716 return error;
717}
718
719/*
720 * Advance to the next id in the current chunk, or if at the
721 * end of the chunk, skip ahead to first id in next allocated chunk
722 * using the SEEK_DATA interface.
723 */
724static int
725xfs_dq_get_next_id(
726 struct xfs_mount *mp,
727 xfs_dqtype_t type,
728 xfs_dqid_t *id)
729{
730 struct xfs_inode *quotip = xfs_quota_inode(mp, type);
731 xfs_dqid_t next_id = *id + 1; /* simple advance */
732 uint lock_flags;
733 struct xfs_bmbt_irec got;
734 struct xfs_iext_cursor cur;
735 xfs_fsblock_t start;
736 int error = 0;
737
738 /* If we'd wrap past the max ID, stop */
739 if (next_id < *id)
740 return -ENOENT;
741
742 /* If new ID is within the current chunk, advancing it sufficed */
743 if (next_id % mp->m_quotainfo->qi_dqperchunk) {
744 *id = next_id;
745 return 0;
746 }
747
748 /* Nope, next_id is now past the current chunk, so find the next one */
749 start = (xfs_fsblock_t)next_id / mp->m_quotainfo->qi_dqperchunk;
750
751 lock_flags = xfs_ilock_data_map_shared(quotip);
752 error = xfs_iread_extents(NULL, quotip, XFS_DATA_FORK);
753 if (error)
754 return error;
755
756 if (xfs_iext_lookup_extent(quotip, &quotip->i_df, start, &cur, &got)) {
757 /* contiguous chunk, bump startoff for the id calculation */
758 if (got.br_startoff < start)
759 got.br_startoff = start;
760 *id = got.br_startoff * mp->m_quotainfo->qi_dqperchunk;
761 } else {
762 error = -ENOENT;
763 }
764
765 xfs_iunlock(quotip, lock_flags);
766
767 return error;
768}
769
770/*
771 * Look up the dquot in the in-core cache. If found, the dquot is returned
772 * locked and ready to go.
773 */
774static struct xfs_dquot *
775xfs_qm_dqget_cache_lookup(
776 struct xfs_mount *mp,
777 struct xfs_quotainfo *qi,
778 struct radix_tree_root *tree,
779 xfs_dqid_t id)
780{
781 struct xfs_dquot *dqp;
782
783restart:
784 mutex_lock(&qi->qi_tree_lock);
785 dqp = radix_tree_lookup(tree, id);
786 if (!dqp) {
787 mutex_unlock(lock: &qi->qi_tree_lock);
788 XFS_STATS_INC(mp, xs_qm_dqcachemisses);
789 return NULL;
790 }
791
792 xfs_dqlock(dqp);
793 if (dqp->q_flags & XFS_DQFLAG_FREEING) {
794 xfs_dqunlock(dqp);
795 mutex_unlock(lock: &qi->qi_tree_lock);
796 trace_xfs_dqget_freeing(dqp);
797 delay(ticks: 1);
798 goto restart;
799 }
800
801 dqp->q_nrefs++;
802 mutex_unlock(lock: &qi->qi_tree_lock);
803
804 trace_xfs_dqget_hit(dqp);
805 XFS_STATS_INC(mp, xs_qm_dqcachehits);
806 return dqp;
807}
808
809/*
810 * Try to insert a new dquot into the in-core cache. If an error occurs the
811 * caller should throw away the dquot and start over. Otherwise, the dquot
812 * is returned locked (and held by the cache) as if there had been a cache
813 * hit.
814 *
815 * The insert needs to be done under memalloc_nofs context because the radix
816 * tree can do memory allocation during insert. The qi->qi_tree_lock is taken in
817 * memory reclaim when freeing unused dquots, so we cannot have the radix tree
818 * node allocation recursing into filesystem reclaim whilst we hold the
819 * qi_tree_lock.
820 */
821static int
822xfs_qm_dqget_cache_insert(
823 struct xfs_mount *mp,
824 struct xfs_quotainfo *qi,
825 struct radix_tree_root *tree,
826 xfs_dqid_t id,
827 struct xfs_dquot *dqp)
828{
829 unsigned int nofs_flags;
830 int error;
831
832 nofs_flags = memalloc_nofs_save();
833 mutex_lock(&qi->qi_tree_lock);
834 error = radix_tree_insert(tree, index: id, dqp);
835 if (unlikely(error)) {
836 /* Duplicate found! Caller must try again. */
837 trace_xfs_dqget_dup(dqp);
838 goto out_unlock;
839 }
840
841 /* Return a locked dquot to the caller, with a reference taken. */
842 xfs_dqlock(dqp);
843 dqp->q_nrefs = 1;
844 qi->qi_dquots++;
845
846out_unlock:
847 mutex_unlock(lock: &qi->qi_tree_lock);
848 memalloc_nofs_restore(flags: nofs_flags);
849 return error;
850}
851
852/* Check our input parameters. */
853static int
854xfs_qm_dqget_checks(
855 struct xfs_mount *mp,
856 xfs_dqtype_t type)
857{
858 switch (type) {
859 case XFS_DQTYPE_USER:
860 if (!XFS_IS_UQUOTA_ON(mp))
861 return -ESRCH;
862 return 0;
863 case XFS_DQTYPE_GROUP:
864 if (!XFS_IS_GQUOTA_ON(mp))
865 return -ESRCH;
866 return 0;
867 case XFS_DQTYPE_PROJ:
868 if (!XFS_IS_PQUOTA_ON(mp))
869 return -ESRCH;
870 return 0;
871 default:
872 WARN_ON_ONCE(0);
873 return -EINVAL;
874 }
875}
876
877/*
878 * Given the file system, id, and type (UDQUOT/GDQUOT/PDQUOT), return a
879 * locked dquot, doing an allocation (if requested) as needed.
880 */
881int
882xfs_qm_dqget(
883 struct xfs_mount *mp,
884 xfs_dqid_t id,
885 xfs_dqtype_t type,
886 bool can_alloc,
887 struct xfs_dquot **O_dqpp)
888{
889 struct xfs_quotainfo *qi = mp->m_quotainfo;
890 struct radix_tree_root *tree = xfs_dquot_tree(qi, type);
891 struct xfs_dquot *dqp;
892 int error;
893
894 error = xfs_qm_dqget_checks(mp, type);
895 if (error)
896 return error;
897
898restart:
899 dqp = xfs_qm_dqget_cache_lookup(mp, qi, tree, id);
900 if (dqp) {
901 *O_dqpp = dqp;
902 return 0;
903 }
904
905 error = xfs_qm_dqread(mp, id, type, can_alloc, &dqp);
906 if (error)
907 return error;
908
909 error = xfs_qm_dqget_cache_insert(mp, qi, tree, id, dqp);
910 if (error) {
911 /*
912 * Duplicate found. Just throw away the new dquot and start
913 * over.
914 */
915 xfs_qm_dqdestroy(dqp);
916 XFS_STATS_INC(mp, xs_qm_dquot_dups);
917 goto restart;
918 }
919
920 trace_xfs_dqget_miss(dqp);
921 *O_dqpp = dqp;
922 return 0;
923}
924
925/*
926 * Given a dquot id and type, read and initialize a dquot from the on-disk
927 * metadata. This function is only for use during quota initialization so
928 * it ignores the dquot cache assuming that the dquot shrinker isn't set up.
929 * The caller is responsible for _qm_dqdestroy'ing the returned dquot.
930 */
931int
932xfs_qm_dqget_uncached(
933 struct xfs_mount *mp,
934 xfs_dqid_t id,
935 xfs_dqtype_t type,
936 struct xfs_dquot **dqpp)
937{
938 int error;
939
940 error = xfs_qm_dqget_checks(mp, type);
941 if (error)
942 return error;
943
944 return xfs_qm_dqread(mp, id, type, 0, dqpp);
945}
946
947/* Return the quota id for a given inode and type. */
948xfs_dqid_t
949xfs_qm_id_for_quotatype(
950 struct xfs_inode *ip,
951 xfs_dqtype_t type)
952{
953 switch (type) {
954 case XFS_DQTYPE_USER:
955 return i_uid_read(inode: VFS_I(ip));
956 case XFS_DQTYPE_GROUP:
957 return i_gid_read(inode: VFS_I(ip));
958 case XFS_DQTYPE_PROJ:
959 return ip->i_projid;
960 }
961 ASSERT(0);
962 return 0;
963}
964
965/*
966 * Return the dquot for a given inode and type. If @can_alloc is true, then
967 * allocate blocks if needed. The inode's ILOCK must be held and it must not
968 * have already had an inode attached.
969 */
970int
971xfs_qm_dqget_inode(
972 struct xfs_inode *ip,
973 xfs_dqtype_t type,
974 bool can_alloc,
975 struct xfs_dquot **O_dqpp)
976{
977 struct xfs_mount *mp = ip->i_mount;
978 struct xfs_quotainfo *qi = mp->m_quotainfo;
979 struct radix_tree_root *tree = xfs_dquot_tree(qi, type);
980 struct xfs_dquot *dqp;
981 xfs_dqid_t id;
982 int error;
983
984 error = xfs_qm_dqget_checks(mp, type);
985 if (error)
986 return error;
987
988 xfs_assert_ilocked(ip, XFS_ILOCK_EXCL);
989 ASSERT(xfs_inode_dquot(ip, type) == NULL);
990
991 id = xfs_qm_id_for_quotatype(ip, type);
992
993restart:
994 dqp = xfs_qm_dqget_cache_lookup(mp, qi, tree, id);
995 if (dqp) {
996 *O_dqpp = dqp;
997 return 0;
998 }
999
1000 /*
1001 * Dquot cache miss. We don't want to keep the inode lock across
1002 * a (potential) disk read. Also we don't want to deal with the lock
1003 * ordering between quotainode and this inode. OTOH, dropping the inode
1004 * lock here means dealing with a chown that can happen before
1005 * we re-acquire the lock.
1006 */
1007 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1008 error = xfs_qm_dqread(mp, id, type, can_alloc, &dqp);
1009 xfs_ilock(ip, XFS_ILOCK_EXCL);
1010 if (error)
1011 return error;
1012
1013 /*
1014 * A dquot could be attached to this inode by now, since we had
1015 * dropped the ilock.
1016 */
1017 if (xfs_this_quota_on(mp, type)) {
1018 struct xfs_dquot *dqp1;
1019
1020 dqp1 = xfs_inode_dquot(ip, type);
1021 if (dqp1) {
1022 xfs_qm_dqdestroy(dqp);
1023 dqp = dqp1;
1024 xfs_dqlock(dqp);
1025 goto dqret;
1026 }
1027 } else {
1028 /* inode stays locked on return */
1029 xfs_qm_dqdestroy(dqp);
1030 return -ESRCH;
1031 }
1032
1033 error = xfs_qm_dqget_cache_insert(mp, qi, tree, id, dqp);
1034 if (error) {
1035 /*
1036 * Duplicate found. Just throw away the new dquot and start
1037 * over.
1038 */
1039 xfs_qm_dqdestroy(dqp);
1040 XFS_STATS_INC(mp, xs_qm_dquot_dups);
1041 goto restart;
1042 }
1043
1044dqret:
1045 xfs_assert_ilocked(ip, XFS_ILOCK_EXCL);
1046 trace_xfs_dqget_miss(dqp);
1047 *O_dqpp = dqp;
1048 return 0;
1049}
1050
1051/*
1052 * Starting at @id and progressing upwards, look for an initialized incore
1053 * dquot, lock it, and return it.
1054 */
1055int
1056xfs_qm_dqget_next(
1057 struct xfs_mount *mp,
1058 xfs_dqid_t id,
1059 xfs_dqtype_t type,
1060 struct xfs_dquot **dqpp)
1061{
1062 struct xfs_dquot *dqp;
1063 int error = 0;
1064
1065 *dqpp = NULL;
1066 for (; !error; error = xfs_dq_get_next_id(mp, type, &id)) {
1067 error = xfs_qm_dqget(mp, id, type, false, &dqp);
1068 if (error == -ENOENT)
1069 continue;
1070 else if (error != 0)
1071 break;
1072
1073 if (!XFS_IS_DQUOT_UNINITIALIZED(dqp)) {
1074 *dqpp = dqp;
1075 return 0;
1076 }
1077
1078 xfs_qm_dqput(dqp);
1079 }
1080
1081 return error;
1082}
1083
1084/*
1085 * Release a reference to the dquot (decrement ref-count) and unlock it.
1086 *
1087 * If there is a group quota attached to this dquot, carefully release that
1088 * too without tripping over deadlocks'n'stuff.
1089 */
1090void
1091xfs_qm_dqput(
1092 struct xfs_dquot *dqp)
1093{
1094 ASSERT(dqp->q_nrefs > 0);
1095 ASSERT(XFS_DQ_IS_LOCKED(dqp));
1096
1097 trace_xfs_dqput(dqp);
1098
1099 if (--dqp->q_nrefs == 0) {
1100 struct xfs_quotainfo *qi = dqp->q_mount->m_quotainfo;
1101 trace_xfs_dqput_free(dqp);
1102
1103 if (list_lru_add_obj(lru: &qi->qi_lru, item: &dqp->q_lru))
1104 XFS_STATS_INC(dqp->q_mount, xs_qm_dquot_unused);
1105 }
1106 xfs_dqunlock(dqp);
1107}
1108
1109/*
1110 * Release a dquot. Flush it if dirty, then dqput() it.
1111 * dquot must not be locked.
1112 */
1113void
1114xfs_qm_dqrele(
1115 struct xfs_dquot *dqp)
1116{
1117 if (!dqp)
1118 return;
1119
1120 trace_xfs_dqrele(dqp);
1121
1122 xfs_dqlock(dqp);
1123 /*
1124 * We don't care to flush it if the dquot is dirty here.
1125 * That will create stutters that we want to avoid.
1126 * Instead we do a delayed write when we try to reclaim
1127 * a dirty dquot. Also xfs_sync will take part of the burden...
1128 */
1129 xfs_qm_dqput(dqp);
1130}
1131
1132/*
1133 * This is the dquot flushing I/O completion routine. It is called
1134 * from interrupt level when the buffer containing the dquot is
1135 * flushed to disk. It is responsible for removing the dquot logitem
1136 * from the AIL if it has not been re-logged, and unlocking the dquot's
1137 * flush lock. This behavior is very similar to that of inodes..
1138 */
1139static void
1140xfs_qm_dqflush_done(
1141 struct xfs_log_item *lip)
1142{
1143 struct xfs_dq_logitem *qip = (struct xfs_dq_logitem *)lip;
1144 struct xfs_dquot *dqp = qip->qli_dquot;
1145 struct xfs_ail *ailp = lip->li_ailp;
1146 xfs_lsn_t tail_lsn;
1147
1148 /*
1149 * We only want to pull the item from the AIL if its
1150 * location in the log has not changed since we started the flush.
1151 * Thus, we only bother if the dquot's lsn has
1152 * not changed. First we check the lsn outside the lock
1153 * since it's cheaper, and then we recheck while
1154 * holding the lock before removing the dquot from the AIL.
1155 */
1156 if (test_bit(XFS_LI_IN_AIL, &lip->li_flags) &&
1157 ((lip->li_lsn == qip->qli_flush_lsn) ||
1158 test_bit(XFS_LI_FAILED, &lip->li_flags))) {
1159
1160 spin_lock(lock: &ailp->ail_lock);
1161 xfs_clear_li_failed(lip);
1162 if (lip->li_lsn == qip->qli_flush_lsn) {
1163 /* xfs_ail_update_finish() drops the AIL lock */
1164 tail_lsn = xfs_ail_delete_one(ailp, lip);
1165 xfs_ail_update_finish(ailp, tail_lsn);
1166 } else {
1167 spin_unlock(lock: &ailp->ail_lock);
1168 }
1169 }
1170
1171 /*
1172 * Release the dq's flush lock since we're done with it.
1173 */
1174 xfs_dqfunlock(dqp);
1175}
1176
1177void
1178xfs_buf_dquot_iodone(
1179 struct xfs_buf *bp)
1180{
1181 struct xfs_log_item *lip, *n;
1182
1183 list_for_each_entry_safe(lip, n, &bp->b_li_list, li_bio_list) {
1184 list_del_init(entry: &lip->li_bio_list);
1185 xfs_qm_dqflush_done(lip);
1186 }
1187}
1188
1189void
1190xfs_buf_dquot_io_fail(
1191 struct xfs_buf *bp)
1192{
1193 struct xfs_log_item *lip;
1194
1195 spin_lock(lock: &bp->b_mount->m_ail->ail_lock);
1196 list_for_each_entry(lip, &bp->b_li_list, li_bio_list)
1197 xfs_set_li_failed(lip, bp);
1198 spin_unlock(lock: &bp->b_mount->m_ail->ail_lock);
1199}
1200
1201/* Check incore dquot for errors before we flush. */
1202static xfs_failaddr_t
1203xfs_qm_dqflush_check(
1204 struct xfs_dquot *dqp)
1205{
1206 xfs_dqtype_t type = xfs_dquot_type(dqp);
1207
1208 if (type != XFS_DQTYPE_USER &&
1209 type != XFS_DQTYPE_GROUP &&
1210 type != XFS_DQTYPE_PROJ)
1211 return __this_address;
1212
1213 if (dqp->q_id == 0)
1214 return NULL;
1215
1216 if (dqp->q_blk.softlimit && dqp->q_blk.count > dqp->q_blk.softlimit &&
1217 !dqp->q_blk.timer)
1218 return __this_address;
1219
1220 if (dqp->q_ino.softlimit && dqp->q_ino.count > dqp->q_ino.softlimit &&
1221 !dqp->q_ino.timer)
1222 return __this_address;
1223
1224 if (dqp->q_rtb.softlimit && dqp->q_rtb.count > dqp->q_rtb.softlimit &&
1225 !dqp->q_rtb.timer)
1226 return __this_address;
1227
1228 /* bigtime flag should never be set on root dquots */
1229 if (dqp->q_type & XFS_DQTYPE_BIGTIME) {
1230 if (!xfs_has_bigtime(mp: dqp->q_mount))
1231 return __this_address;
1232 if (dqp->q_id == 0)
1233 return __this_address;
1234 }
1235
1236 return NULL;
1237}
1238
1239/*
1240 * Write a modified dquot to disk.
1241 * The dquot must be locked and the flush lock too taken by caller.
1242 * The flush lock will not be unlocked until the dquot reaches the disk,
1243 * but the dquot is free to be unlocked and modified by the caller
1244 * in the interim. Dquot is still locked on return. This behavior is
1245 * identical to that of inodes.
1246 */
1247int
1248xfs_qm_dqflush(
1249 struct xfs_dquot *dqp,
1250 struct xfs_buf **bpp)
1251{
1252 struct xfs_mount *mp = dqp->q_mount;
1253 struct xfs_log_item *lip = &dqp->q_logitem.qli_item;
1254 struct xfs_buf *bp;
1255 struct xfs_dqblk *dqblk;
1256 xfs_failaddr_t fa;
1257 int error;
1258
1259 ASSERT(XFS_DQ_IS_LOCKED(dqp));
1260 ASSERT(!completion_done(&dqp->q_flush));
1261
1262 trace_xfs_dqflush(dqp);
1263
1264 *bpp = NULL;
1265
1266 xfs_qm_dqunpin_wait(dqp);
1267
1268 /*
1269 * Get the buffer containing the on-disk dquot
1270 */
1271 error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, dqp->q_blkno,
1272 mp->m_quotainfo->qi_dqchunklen, XBF_TRYLOCK,
1273 &bp, &xfs_dquot_buf_ops);
1274 if (error == -EAGAIN)
1275 goto out_unlock;
1276 if (xfs_metadata_is_sick(error))
1277 xfs_dquot_mark_sick(dqp);
1278 if (error)
1279 goto out_abort;
1280
1281 fa = xfs_qm_dqflush_check(dqp);
1282 if (fa) {
1283 xfs_alert(mp, "corrupt dquot ID 0x%x in memory at %pS",
1284 dqp->q_id, fa);
1285 xfs_buf_relse(bp);
1286 xfs_dquot_mark_sick(dqp);
1287 error = -EFSCORRUPTED;
1288 goto out_abort;
1289 }
1290
1291 /* Flush the incore dquot to the ondisk buffer. */
1292 dqblk = xfs_buf_offset(bp, dqp->q_bufoffset);
1293 xfs_dquot_to_disk(ddqp: &dqblk->dd_diskdq, dqp);
1294
1295 /*
1296 * Clear the dirty field and remember the flush lsn for later use.
1297 */
1298 dqp->q_flags &= ~XFS_DQFLAG_DIRTY;
1299
1300 xfs_trans_ail_copy_lsn(mp->m_ail, &dqp->q_logitem.qli_flush_lsn,
1301 &dqp->q_logitem.qli_item.li_lsn);
1302
1303 /*
1304 * copy the lsn into the on-disk dquot now while we have the in memory
1305 * dquot here. This can't be done later in the write verifier as we
1306 * can't get access to the log item at that point in time.
1307 *
1308 * We also calculate the CRC here so that the on-disk dquot in the
1309 * buffer always has a valid CRC. This ensures there is no possibility
1310 * of a dquot without an up-to-date CRC getting to disk.
1311 */
1312 if (xfs_has_crc(mp)) {
1313 dqblk->dd_lsn = cpu_to_be64(dqp->q_logitem.qli_item.li_lsn);
1314 xfs_update_cksum((char *)dqblk, sizeof(struct xfs_dqblk),
1315 XFS_DQUOT_CRC_OFF);
1316 }
1317
1318 /*
1319 * Attach the dquot to the buffer so that we can remove this dquot from
1320 * the AIL and release the flush lock once the dquot is synced to disk.
1321 */
1322 bp->b_flags |= _XBF_DQUOTS;
1323 list_add_tail(new: &dqp->q_logitem.qli_item.li_bio_list, head: &bp->b_li_list);
1324
1325 /*
1326 * If the buffer is pinned then push on the log so we won't
1327 * get stuck waiting in the write for too long.
1328 */
1329 if (xfs_buf_ispinned(bp)) {
1330 trace_xfs_dqflush_force(dqp);
1331 xfs_log_force(mp, flags: 0);
1332 }
1333
1334 trace_xfs_dqflush_done(dqp);
1335 *bpp = bp;
1336 return 0;
1337
1338out_abort:
1339 dqp->q_flags &= ~XFS_DQFLAG_DIRTY;
1340 xfs_trans_ail_delete(lip, shutdown_type: 0);
1341 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1342out_unlock:
1343 xfs_dqfunlock(dqp);
1344 return error;
1345}
1346
1347/*
1348 * Lock two xfs_dquot structures.
1349 *
1350 * To avoid deadlocks we always lock the quota structure with
1351 * the lowerd id first.
1352 */
1353void
1354xfs_dqlock2(
1355 struct xfs_dquot *d1,
1356 struct xfs_dquot *d2)
1357{
1358 if (d1 && d2) {
1359 ASSERT(d1 != d2);
1360 if (d1->q_id > d2->q_id) {
1361 mutex_lock(&d2->q_qlock);
1362 mutex_lock_nested(lock: &d1->q_qlock, subclass: XFS_QLOCK_NESTED);
1363 } else {
1364 mutex_lock(&d1->q_qlock);
1365 mutex_lock_nested(lock: &d2->q_qlock, subclass: XFS_QLOCK_NESTED);
1366 }
1367 } else if (d1) {
1368 mutex_lock(&d1->q_qlock);
1369 } else if (d2) {
1370 mutex_lock(&d2->q_qlock);
1371 }
1372}
1373
1374int __init
1375xfs_qm_init(void)
1376{
1377 xfs_dquot_cache = kmem_cache_create(name: "xfs_dquot",
1378 size: sizeof(struct xfs_dquot),
1379 align: 0, flags: 0, NULL);
1380 if (!xfs_dquot_cache)
1381 goto out;
1382
1383 xfs_dqtrx_cache = kmem_cache_create(name: "xfs_dqtrx",
1384 size: sizeof(struct xfs_dquot_acct),
1385 align: 0, flags: 0, NULL);
1386 if (!xfs_dqtrx_cache)
1387 goto out_free_dquot_cache;
1388
1389 return 0;
1390
1391out_free_dquot_cache:
1392 kmem_cache_destroy(s: xfs_dquot_cache);
1393out:
1394 return -ENOMEM;
1395}
1396
1397void
1398xfs_qm_exit(void)
1399{
1400 kmem_cache_destroy(s: xfs_dqtrx_cache);
1401 kmem_cache_destroy(s: xfs_dquot_cache);
1402}
1403

source code of linux/fs/xfs/xfs_dquot.c