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-rw-r--r--fs/xfs/xfs_dquot.c1454
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diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c
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1/*
2 * Copyright (c) 2000-2003 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_bit.h"
21#include "xfs_log.h"
22#include "xfs_inum.h"
23#include "xfs_trans.h"
24#include "xfs_sb.h"
25#include "xfs_ag.h"
26#include "xfs_alloc.h"
27#include "xfs_quota.h"
28#include "xfs_mount.h"
29#include "xfs_bmap_btree.h"
30#include "xfs_inode.h"
31#include "xfs_bmap.h"
32#include "xfs_rtalloc.h"
33#include "xfs_error.h"
34#include "xfs_itable.h"
35#include "xfs_attr.h"
36#include "xfs_buf_item.h"
37#include "xfs_trans_space.h"
38#include "xfs_trans_priv.h"
39#include "xfs_qm.h"
40#include "xfs_trace.h"
41
42
43/*
44 LOCK ORDER
45
46 inode lock (ilock)
47 dquot hash-chain lock (hashlock)
48 xqm dquot freelist lock (freelistlock
49 mount's dquot list lock (mplistlock)
50 user dquot lock - lock ordering among dquots is based on the uid or gid
51 group dquot lock - similar to udquots. Between the two dquots, the udquot
52 has to be locked first.
53 pin lock - the dquot lock must be held to take this lock.
54 flush lock - ditto.
55*/
56
57#ifdef DEBUG
58xfs_buftarg_t *xfs_dqerror_target;
59int xfs_do_dqerror;
60int xfs_dqreq_num;
61int xfs_dqerror_mod = 33;
62#endif
63
64static struct lock_class_key xfs_dquot_other_class;
65
66/*
67 * Allocate and initialize a dquot. We don't always allocate fresh memory;
68 * we try to reclaim a free dquot if the number of incore dquots are above
69 * a threshold.
70 * The only field inside the core that gets initialized at this point
71 * is the d_id field. The idea is to fill in the entire q_core
72 * when we read in the on disk dquot.
73 */
74STATIC xfs_dquot_t *
75xfs_qm_dqinit(
76 xfs_mount_t *mp,
77 xfs_dqid_t id,
78 uint type)
79{
80 xfs_dquot_t *dqp;
81 boolean_t brandnewdquot;
82
83 brandnewdquot = xfs_qm_dqalloc_incore(&dqp);
84 dqp->dq_flags = type;
85 dqp->q_core.d_id = cpu_to_be32(id);
86 dqp->q_mount = mp;
87
88 /*
89 * No need to re-initialize these if this is a reclaimed dquot.
90 */
91 if (brandnewdquot) {
92 INIT_LIST_HEAD(&dqp->q_freelist);
93 mutex_init(&dqp->q_qlock);
94 init_waitqueue_head(&dqp->q_pinwait);
95
96 /*
97 * Because we want to use a counting completion, complete
98 * the flush completion once to allow a single access to
99 * the flush completion without blocking.
100 */
101 init_completion(&dqp->q_flush);
102 complete(&dqp->q_flush);
103
104 trace_xfs_dqinit(dqp);
105 } else {
106 /*
107 * Only the q_core portion was zeroed in dqreclaim_one().
108 * So, we need to reset others.
109 */
110 dqp->q_nrefs = 0;
111 dqp->q_blkno = 0;
112 INIT_LIST_HEAD(&dqp->q_mplist);
113 INIT_LIST_HEAD(&dqp->q_hashlist);
114 dqp->q_bufoffset = 0;
115 dqp->q_fileoffset = 0;
116 dqp->q_transp = NULL;
117 dqp->q_gdquot = NULL;
118 dqp->q_res_bcount = 0;
119 dqp->q_res_icount = 0;
120 dqp->q_res_rtbcount = 0;
121 atomic_set(&dqp->q_pincount, 0);
122 dqp->q_hash = NULL;
123 ASSERT(list_empty(&dqp->q_freelist));
124
125 trace_xfs_dqreuse(dqp);
126 }
127
128 /*
129 * In either case we need to make sure group quotas have a different
130 * lock class than user quotas, to make sure lockdep knows we can
131 * locks of one of each at the same time.
132 */
133 if (!(type & XFS_DQ_USER))
134 lockdep_set_class(&dqp->q_qlock, &xfs_dquot_other_class);
135
136 /*
137 * log item gets initialized later
138 */
139 return (dqp);
140}
141
142/*
143 * This is called to free all the memory associated with a dquot
144 */
145void
146xfs_qm_dqdestroy(
147 xfs_dquot_t *dqp)
148{
149 ASSERT(list_empty(&dqp->q_freelist));
150
151 mutex_destroy(&dqp->q_qlock);
152 kmem_zone_free(xfs_Gqm->qm_dqzone, dqp);
153
154 atomic_dec(&xfs_Gqm->qm_totaldquots);
155}
156
157/*
158 * This is what a 'fresh' dquot inside a dquot chunk looks like on disk.
159 */
160STATIC void
161xfs_qm_dqinit_core(
162 xfs_dqid_t id,
163 uint type,
164 xfs_dqblk_t *d)
165{
166 /*
167 * Caller has zero'd the entire dquot 'chunk' already.
168 */
169 d->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC);
170 d->dd_diskdq.d_version = XFS_DQUOT_VERSION;
171 d->dd_diskdq.d_id = cpu_to_be32(id);
172 d->dd_diskdq.d_flags = type;
173}
174
175/*
176 * If default limits are in force, push them into the dquot now.
177 * We overwrite the dquot limits only if they are zero and this
178 * is not the root dquot.
179 */
180void
181xfs_qm_adjust_dqlimits(
182 xfs_mount_t *mp,
183 xfs_disk_dquot_t *d)
184{
185 xfs_quotainfo_t *q = mp->m_quotainfo;
186
187 ASSERT(d->d_id);
188
189 if (q->qi_bsoftlimit && !d->d_blk_softlimit)
190 d->d_blk_softlimit = cpu_to_be64(q->qi_bsoftlimit);
191 if (q->qi_bhardlimit && !d->d_blk_hardlimit)
192 d->d_blk_hardlimit = cpu_to_be64(q->qi_bhardlimit);
193 if (q->qi_isoftlimit && !d->d_ino_softlimit)
194 d->d_ino_softlimit = cpu_to_be64(q->qi_isoftlimit);
195 if (q->qi_ihardlimit && !d->d_ino_hardlimit)
196 d->d_ino_hardlimit = cpu_to_be64(q->qi_ihardlimit);
197 if (q->qi_rtbsoftlimit && !d->d_rtb_softlimit)
198 d->d_rtb_softlimit = cpu_to_be64(q->qi_rtbsoftlimit);
199 if (q->qi_rtbhardlimit && !d->d_rtb_hardlimit)
200 d->d_rtb_hardlimit = cpu_to_be64(q->qi_rtbhardlimit);
201}
202
203/*
204 * Check the limits and timers of a dquot and start or reset timers
205 * if necessary.
206 * This gets called even when quota enforcement is OFF, which makes our
207 * life a little less complicated. (We just don't reject any quota
208 * reservations in that case, when enforcement is off).
209 * We also return 0 as the values of the timers in Q_GETQUOTA calls, when
210 * enforcement's off.
211 * In contrast, warnings are a little different in that they don't
212 * 'automatically' get started when limits get exceeded. They do
213 * get reset to zero, however, when we find the count to be under
214 * the soft limit (they are only ever set non-zero via userspace).
215 */
216void
217xfs_qm_adjust_dqtimers(
218 xfs_mount_t *mp,
219 xfs_disk_dquot_t *d)
220{
221 ASSERT(d->d_id);
222
223#ifdef DEBUG
224 if (d->d_blk_hardlimit)
225 ASSERT(be64_to_cpu(d->d_blk_softlimit) <=
226 be64_to_cpu(d->d_blk_hardlimit));
227 if (d->d_ino_hardlimit)
228 ASSERT(be64_to_cpu(d->d_ino_softlimit) <=
229 be64_to_cpu(d->d_ino_hardlimit));
230 if (d->d_rtb_hardlimit)
231 ASSERT(be64_to_cpu(d->d_rtb_softlimit) <=
232 be64_to_cpu(d->d_rtb_hardlimit));
233#endif
234
235 if (!d->d_btimer) {
236 if ((d->d_blk_softlimit &&
237 (be64_to_cpu(d->d_bcount) >=
238 be64_to_cpu(d->d_blk_softlimit))) ||
239 (d->d_blk_hardlimit &&
240 (be64_to_cpu(d->d_bcount) >=
241 be64_to_cpu(d->d_blk_hardlimit)))) {
242 d->d_btimer = cpu_to_be32(get_seconds() +
243 mp->m_quotainfo->qi_btimelimit);
244 } else {
245 d->d_bwarns = 0;
246 }
247 } else {
248 if ((!d->d_blk_softlimit ||
249 (be64_to_cpu(d->d_bcount) <
250 be64_to_cpu(d->d_blk_softlimit))) &&
251 (!d->d_blk_hardlimit ||
252 (be64_to_cpu(d->d_bcount) <
253 be64_to_cpu(d->d_blk_hardlimit)))) {
254 d->d_btimer = 0;
255 }
256 }
257
258 if (!d->d_itimer) {
259 if ((d->d_ino_softlimit &&
260 (be64_to_cpu(d->d_icount) >=
261 be64_to_cpu(d->d_ino_softlimit))) ||
262 (d->d_ino_hardlimit &&
263 (be64_to_cpu(d->d_icount) >=
264 be64_to_cpu(d->d_ino_hardlimit)))) {
265 d->d_itimer = cpu_to_be32(get_seconds() +
266 mp->m_quotainfo->qi_itimelimit);
267 } else {
268 d->d_iwarns = 0;
269 }
270 } else {
271 if ((!d->d_ino_softlimit ||
272 (be64_to_cpu(d->d_icount) <
273 be64_to_cpu(d->d_ino_softlimit))) &&
274 (!d->d_ino_hardlimit ||
275 (be64_to_cpu(d->d_icount) <
276 be64_to_cpu(d->d_ino_hardlimit)))) {
277 d->d_itimer = 0;
278 }
279 }
280
281 if (!d->d_rtbtimer) {
282 if ((d->d_rtb_softlimit &&
283 (be64_to_cpu(d->d_rtbcount) >=
284 be64_to_cpu(d->d_rtb_softlimit))) ||
285 (d->d_rtb_hardlimit &&
286 (be64_to_cpu(d->d_rtbcount) >=
287 be64_to_cpu(d->d_rtb_hardlimit)))) {
288 d->d_rtbtimer = cpu_to_be32(get_seconds() +
289 mp->m_quotainfo->qi_rtbtimelimit);
290 } else {
291 d->d_rtbwarns = 0;
292 }
293 } else {
294 if ((!d->d_rtb_softlimit ||
295 (be64_to_cpu(d->d_rtbcount) <
296 be64_to_cpu(d->d_rtb_softlimit))) &&
297 (!d->d_rtb_hardlimit ||
298 (be64_to_cpu(d->d_rtbcount) <
299 be64_to_cpu(d->d_rtb_hardlimit)))) {
300 d->d_rtbtimer = 0;
301 }
302 }
303}
304
305/*
306 * initialize a buffer full of dquots and log the whole thing
307 */
308STATIC void
309xfs_qm_init_dquot_blk(
310 xfs_trans_t *tp,
311 xfs_mount_t *mp,
312 xfs_dqid_t id,
313 uint type,
314 xfs_buf_t *bp)
315{
316 struct xfs_quotainfo *q = mp->m_quotainfo;
317 xfs_dqblk_t *d;
318 int curid, i;
319
320 ASSERT(tp);
321 ASSERT(xfs_buf_islocked(bp));
322
323 d = bp->b_addr;
324
325 /*
326 * ID of the first dquot in the block - id's are zero based.
327 */
328 curid = id - (id % q->qi_dqperchunk);
329 ASSERT(curid >= 0);
330 memset(d, 0, BBTOB(q->qi_dqchunklen));
331 for (i = 0; i < q->qi_dqperchunk; i++, d++, curid++)
332 xfs_qm_dqinit_core(curid, type, d);
333 xfs_trans_dquot_buf(tp, bp,
334 (type & XFS_DQ_USER ? XFS_BLF_UDQUOT_BUF :
335 ((type & XFS_DQ_PROJ) ? XFS_BLF_PDQUOT_BUF :
336 XFS_BLF_GDQUOT_BUF)));
337 xfs_trans_log_buf(tp, bp, 0, BBTOB(q->qi_dqchunklen) - 1);
338}
339
340
341
342/*
343 * Allocate a block and fill it with dquots.
344 * This is called when the bmapi finds a hole.
345 */
346STATIC int
347xfs_qm_dqalloc(
348 xfs_trans_t **tpp,
349 xfs_mount_t *mp,
350 xfs_dquot_t *dqp,
351 xfs_inode_t *quotip,
352 xfs_fileoff_t offset_fsb,
353 xfs_buf_t **O_bpp)
354{
355 xfs_fsblock_t firstblock;
356 xfs_bmap_free_t flist;
357 xfs_bmbt_irec_t map;
358 int nmaps, error, committed;
359 xfs_buf_t *bp;
360 xfs_trans_t *tp = *tpp;
361
362 ASSERT(tp != NULL);
363
364 trace_xfs_dqalloc(dqp);
365
366 /*
367 * Initialize the bmap freelist prior to calling bmapi code.
368 */
369 xfs_bmap_init(&flist, &firstblock);
370 xfs_ilock(quotip, XFS_ILOCK_EXCL);
371 /*
372 * Return if this type of quotas is turned off while we didn't
373 * have an inode lock
374 */
375 if (XFS_IS_THIS_QUOTA_OFF(dqp)) {
376 xfs_iunlock(quotip, XFS_ILOCK_EXCL);
377 return (ESRCH);
378 }
379
380 xfs_trans_ijoin_ref(tp, quotip, XFS_ILOCK_EXCL);
381 nmaps = 1;
382 if ((error = xfs_bmapi(tp, quotip,
383 offset_fsb, XFS_DQUOT_CLUSTER_SIZE_FSB,
384 XFS_BMAPI_METADATA | XFS_BMAPI_WRITE,
385 &firstblock,
386 XFS_QM_DQALLOC_SPACE_RES(mp),
387 &map, &nmaps, &flist))) {
388 goto error0;
389 }
390 ASSERT(map.br_blockcount == XFS_DQUOT_CLUSTER_SIZE_FSB);
391 ASSERT(nmaps == 1);
392 ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&
393 (map.br_startblock != HOLESTARTBLOCK));
394
395 /*
396 * Keep track of the blkno to save a lookup later
397 */
398 dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock);
399
400 /* now we can just get the buffer (there's nothing to read yet) */
401 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp,
402 dqp->q_blkno,
403 mp->m_quotainfo->qi_dqchunklen,
404 0);
405 if (!bp || (error = xfs_buf_geterror(bp)))
406 goto error1;
407 /*
408 * Make a chunk of dquots out of this buffer and log
409 * the entire thing.
410 */
411 xfs_qm_init_dquot_blk(tp, mp, be32_to_cpu(dqp->q_core.d_id),
412 dqp->dq_flags & XFS_DQ_ALLTYPES, bp);
413
414 /*
415 * xfs_bmap_finish() may commit the current transaction and
416 * start a second transaction if the freelist is not empty.
417 *
418 * Since we still want to modify this buffer, we need to
419 * ensure that the buffer is not released on commit of
420 * the first transaction and ensure the buffer is added to the
421 * second transaction.
422 *
423 * If there is only one transaction then don't stop the buffer
424 * from being released when it commits later on.
425 */
426
427 xfs_trans_bhold(tp, bp);
428
429 if ((error = xfs_bmap_finish(tpp, &flist, &committed))) {
430 goto error1;
431 }
432
433 if (committed) {
434 tp = *tpp;
435 xfs_trans_bjoin(tp, bp);
436 } else {
437 xfs_trans_bhold_release(tp, bp);
438 }
439
440 *O_bpp = bp;
441 return 0;
442
443 error1:
444 xfs_bmap_cancel(&flist);
445 error0:
446 xfs_iunlock(quotip, XFS_ILOCK_EXCL);
447
448 return (error);
449}
450
451/*
452 * Maps a dquot to the buffer containing its on-disk version.
453 * This returns a ptr to the buffer containing the on-disk dquot
454 * in the bpp param, and a ptr to the on-disk dquot within that buffer
455 */
456STATIC int
457xfs_qm_dqtobp(
458 xfs_trans_t **tpp,
459 xfs_dquot_t *dqp,
460 xfs_disk_dquot_t **O_ddpp,
461 xfs_buf_t **O_bpp,
462 uint flags)
463{
464 xfs_bmbt_irec_t map;
465 int nmaps = 1, error;
466 xfs_buf_t *bp;
467 xfs_inode_t *quotip = XFS_DQ_TO_QIP(dqp);
468 xfs_mount_t *mp = dqp->q_mount;
469 xfs_disk_dquot_t *ddq;
470 xfs_dqid_t id = be32_to_cpu(dqp->q_core.d_id);
471 xfs_trans_t *tp = (tpp ? *tpp : NULL);
472
473 dqp->q_fileoffset = (xfs_fileoff_t)id / mp->m_quotainfo->qi_dqperchunk;
474
475 xfs_ilock(quotip, XFS_ILOCK_SHARED);
476 if (XFS_IS_THIS_QUOTA_OFF(dqp)) {
477 /*
478 * Return if this type of quotas is turned off while we
479 * didn't have the quota inode lock.
480 */
481 xfs_iunlock(quotip, XFS_ILOCK_SHARED);
482 return ESRCH;
483 }
484
485 /*
486 * Find the block map; no allocations yet
487 */
488 error = xfs_bmapi(NULL, quotip, dqp->q_fileoffset,
489 XFS_DQUOT_CLUSTER_SIZE_FSB, XFS_BMAPI_METADATA,
490 NULL, 0, &map, &nmaps, NULL);
491
492 xfs_iunlock(quotip, XFS_ILOCK_SHARED);
493 if (error)
494 return error;
495
496 ASSERT(nmaps == 1);
497 ASSERT(map.br_blockcount == 1);
498
499 /*
500 * Offset of dquot in the (fixed sized) dquot chunk.
501 */
502 dqp->q_bufoffset = (id % mp->m_quotainfo->qi_dqperchunk) *
503 sizeof(xfs_dqblk_t);
504
505 ASSERT(map.br_startblock != DELAYSTARTBLOCK);
506 if (map.br_startblock == HOLESTARTBLOCK) {
507 /*
508 * We don't allocate unless we're asked to
509 */
510 if (!(flags & XFS_QMOPT_DQALLOC))
511 return ENOENT;
512
513 ASSERT(tp);
514 error = xfs_qm_dqalloc(tpp, mp, dqp, quotip,
515 dqp->q_fileoffset, &bp);
516 if (error)
517 return error;
518 tp = *tpp;
519 } else {
520 trace_xfs_dqtobp_read(dqp);
521
522 /*
523 * store the blkno etc so that we don't have to do the
524 * mapping all the time
525 */
526 dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock);
527
528 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
529 dqp->q_blkno,
530 mp->m_quotainfo->qi_dqchunklen,
531 0, &bp);
532 if (error || !bp)
533 return XFS_ERROR(error);
534 }
535
536 ASSERT(xfs_buf_islocked(bp));
537
538 /*
539 * calculate the location of the dquot inside the buffer.
540 */
541 ddq = bp->b_addr + dqp->q_bufoffset;
542
543 /*
544 * A simple sanity check in case we got a corrupted dquot...
545 */
546 error = xfs_qm_dqcheck(mp, ddq, id, dqp->dq_flags & XFS_DQ_ALLTYPES,
547 flags & (XFS_QMOPT_DQREPAIR|XFS_QMOPT_DOWARN),
548 "dqtobp");
549 if (error) {
550 if (!(flags & XFS_QMOPT_DQREPAIR)) {
551 xfs_trans_brelse(tp, bp);
552 return XFS_ERROR(EIO);
553 }
554 }
555
556 *O_bpp = bp;
557 *O_ddpp = ddq;
558
559 return (0);
560}
561
562
563/*
564 * Read in the ondisk dquot using dqtobp() then copy it to an incore version,
565 * and release the buffer immediately.
566 *
567 */
568/* ARGSUSED */
569STATIC int
570xfs_qm_dqread(
571 xfs_trans_t **tpp,
572 xfs_dqid_t id,
573 xfs_dquot_t *dqp, /* dquot to get filled in */
574 uint flags)
575{
576 xfs_disk_dquot_t *ddqp;
577 xfs_buf_t *bp;
578 int error;
579 xfs_trans_t *tp;
580
581 ASSERT(tpp);
582
583 trace_xfs_dqread(dqp);
584
585 /*
586 * get a pointer to the on-disk dquot and the buffer containing it
587 * dqp already knows its own type (GROUP/USER).
588 */
589 if ((error = xfs_qm_dqtobp(tpp, dqp, &ddqp, &bp, flags))) {
590 return (error);
591 }
592 tp = *tpp;
593
594 /* copy everything from disk dquot to the incore dquot */
595 memcpy(&dqp->q_core, ddqp, sizeof(xfs_disk_dquot_t));
596 ASSERT(be32_to_cpu(dqp->q_core.d_id) == id);
597 xfs_qm_dquot_logitem_init(dqp);
598
599 /*
600 * Reservation counters are defined as reservation plus current usage
601 * to avoid having to add every time.
602 */
603 dqp->q_res_bcount = be64_to_cpu(ddqp->d_bcount);
604 dqp->q_res_icount = be64_to_cpu(ddqp->d_icount);
605 dqp->q_res_rtbcount = be64_to_cpu(ddqp->d_rtbcount);
606
607 /* Mark the buf so that this will stay incore a little longer */
608 XFS_BUF_SET_VTYPE_REF(bp, B_FS_DQUOT, XFS_DQUOT_REF);
609
610 /*
611 * We got the buffer with a xfs_trans_read_buf() (in dqtobp())
612 * So we need to release with xfs_trans_brelse().
613 * The strategy here is identical to that of inodes; we lock
614 * the dquot in xfs_qm_dqget() before making it accessible to
615 * others. This is because dquots, like inodes, need a good level of
616 * concurrency, and we don't want to take locks on the entire buffers
617 * for dquot accesses.
618 * Note also that the dquot buffer may even be dirty at this point, if
619 * this particular dquot was repaired. We still aren't afraid to
620 * brelse it because we have the changes incore.
621 */
622 ASSERT(xfs_buf_islocked(bp));
623 xfs_trans_brelse(tp, bp);
624
625 return (error);
626}
627
628
629/*
630 * allocate an incore dquot from the kernel heap,
631 * and fill its core with quota information kept on disk.
632 * If XFS_QMOPT_DQALLOC is set, it'll allocate a dquot on disk
633 * if it wasn't already allocated.
634 */
635STATIC int
636xfs_qm_idtodq(
637 xfs_mount_t *mp,
638 xfs_dqid_t id, /* gid or uid, depending on type */
639 uint type, /* UDQUOT or GDQUOT */
640 uint flags, /* DQALLOC, DQREPAIR */
641 xfs_dquot_t **O_dqpp)/* OUT : incore dquot, not locked */
642{
643 xfs_dquot_t *dqp;
644 int error;
645 xfs_trans_t *tp;
646 int cancelflags=0;
647
648 dqp = xfs_qm_dqinit(mp, id, type);
649 tp = NULL;
650 if (flags & XFS_QMOPT_DQALLOC) {
651 tp = xfs_trans_alloc(mp, XFS_TRANS_QM_DQALLOC);
652 error = xfs_trans_reserve(tp, XFS_QM_DQALLOC_SPACE_RES(mp),
653 XFS_WRITE_LOG_RES(mp) +
654 BBTOB(mp->m_quotainfo->qi_dqchunklen) - 1 +
655 128,
656 0,
657 XFS_TRANS_PERM_LOG_RES,
658 XFS_WRITE_LOG_COUNT);
659 if (error) {
660 cancelflags = 0;
661 goto error0;
662 }
663 cancelflags = XFS_TRANS_RELEASE_LOG_RES;
664 }
665
666 /*
667 * Read it from disk; xfs_dqread() takes care of
668 * all the necessary initialization of dquot's fields (locks, etc)
669 */
670 if ((error = xfs_qm_dqread(&tp, id, dqp, flags))) {
671 /*
672 * This can happen if quotas got turned off (ESRCH),
673 * or if the dquot didn't exist on disk and we ask to
674 * allocate (ENOENT).
675 */
676 trace_xfs_dqread_fail(dqp);
677 cancelflags |= XFS_TRANS_ABORT;
678 goto error0;
679 }
680 if (tp) {
681 if ((error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES)))
682 goto error1;
683 }
684
685 *O_dqpp = dqp;
686 return (0);
687
688 error0:
689 ASSERT(error);
690 if (tp)
691 xfs_trans_cancel(tp, cancelflags);
692 error1:
693 xfs_qm_dqdestroy(dqp);
694 *O_dqpp = NULL;
695 return (error);
696}
697
698/*
699 * Lookup a dquot in the incore dquot hashtable. We keep two separate
700 * hashtables for user and group dquots; and, these are global tables
701 * inside the XQM, not per-filesystem tables.
702 * The hash chain must be locked by caller, and it is left locked
703 * on return. Returning dquot is locked.
704 */
705STATIC int
706xfs_qm_dqlookup(
707 xfs_mount_t *mp,
708 xfs_dqid_t id,
709 xfs_dqhash_t *qh,
710 xfs_dquot_t **O_dqpp)
711{
712 xfs_dquot_t *dqp;
713 uint flist_locked;
714
715 ASSERT(mutex_is_locked(&qh->qh_lock));
716
717 flist_locked = B_FALSE;
718
719 /*
720 * Traverse the hashchain looking for a match
721 */
722 list_for_each_entry(dqp, &qh->qh_list, q_hashlist) {
723 /*
724 * We already have the hashlock. We don't need the
725 * dqlock to look at the id field of the dquot, since the
726 * id can't be modified without the hashlock anyway.
727 */
728 if (be32_to_cpu(dqp->q_core.d_id) == id && dqp->q_mount == mp) {
729 trace_xfs_dqlookup_found(dqp);
730
731 /*
732 * All in core dquots must be on the dqlist of mp
733 */
734 ASSERT(!list_empty(&dqp->q_mplist));
735
736 xfs_dqlock(dqp);
737 if (dqp->q_nrefs == 0) {
738 ASSERT(!list_empty(&dqp->q_freelist));
739 if (!mutex_trylock(&xfs_Gqm->qm_dqfrlist_lock)) {
740 trace_xfs_dqlookup_want(dqp);
741
742 /*
743 * We may have raced with dqreclaim_one()
744 * (and lost). So, flag that we don't
745 * want the dquot to be reclaimed.
746 */
747 dqp->dq_flags |= XFS_DQ_WANT;
748 xfs_dqunlock(dqp);
749 mutex_lock(&xfs_Gqm->qm_dqfrlist_lock);
750 xfs_dqlock(dqp);
751 dqp->dq_flags &= ~(XFS_DQ_WANT);
752 }
753 flist_locked = B_TRUE;
754 }
755
756 /*
757 * id couldn't have changed; we had the hashlock all
758 * along
759 */
760 ASSERT(be32_to_cpu(dqp->q_core.d_id) == id);
761
762 if (flist_locked) {
763 if (dqp->q_nrefs != 0) {
764 mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
765 flist_locked = B_FALSE;
766 } else {
767 /* take it off the freelist */
768 trace_xfs_dqlookup_freelist(dqp);
769 list_del_init(&dqp->q_freelist);
770 xfs_Gqm->qm_dqfrlist_cnt--;
771 }
772 }
773
774 XFS_DQHOLD(dqp);
775
776 if (flist_locked)
777 mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
778 /*
779 * move the dquot to the front of the hashchain
780 */
781 ASSERT(mutex_is_locked(&qh->qh_lock));
782 list_move(&dqp->q_hashlist, &qh->qh_list);
783 trace_xfs_dqlookup_done(dqp);
784 *O_dqpp = dqp;
785 return 0;
786 }
787 }
788
789 *O_dqpp = NULL;
790 ASSERT(mutex_is_locked(&qh->qh_lock));
791 return (1);
792}
793
794/*
795 * Given the file system, inode OR id, and type (UDQUOT/GDQUOT), return a
796 * a locked dquot, doing an allocation (if requested) as needed.
797 * When both an inode and an id are given, the inode's id takes precedence.
798 * That is, if the id changes while we don't hold the ilock inside this
799 * function, the new dquot is returned, not necessarily the one requested
800 * in the id argument.
801 */
802int
803xfs_qm_dqget(
804 xfs_mount_t *mp,
805 xfs_inode_t *ip, /* locked inode (optional) */
806 xfs_dqid_t id, /* uid/projid/gid depending on type */
807 uint type, /* XFS_DQ_USER/XFS_DQ_PROJ/XFS_DQ_GROUP */
808 uint flags, /* DQALLOC, DQSUSER, DQREPAIR, DOWARN */
809 xfs_dquot_t **O_dqpp) /* OUT : locked incore dquot */
810{
811 xfs_dquot_t *dqp;
812 xfs_dqhash_t *h;
813 uint version;
814 int error;
815
816 ASSERT(XFS_IS_QUOTA_RUNNING(mp));
817 if ((! XFS_IS_UQUOTA_ON(mp) && type == XFS_DQ_USER) ||
818 (! XFS_IS_PQUOTA_ON(mp) && type == XFS_DQ_PROJ) ||
819 (! XFS_IS_GQUOTA_ON(mp) && type == XFS_DQ_GROUP)) {
820 return (ESRCH);
821 }
822 h = XFS_DQ_HASH(mp, id, type);
823
824#ifdef DEBUG
825 if (xfs_do_dqerror) {
826 if ((xfs_dqerror_target == mp->m_ddev_targp) &&
827 (xfs_dqreq_num++ % xfs_dqerror_mod) == 0) {
828 xfs_debug(mp, "Returning error in dqget");
829 return (EIO);
830 }
831 }
832#endif
833
834 again:
835
836#ifdef DEBUG
837 ASSERT(type == XFS_DQ_USER ||
838 type == XFS_DQ_PROJ ||
839 type == XFS_DQ_GROUP);
840 if (ip) {
841 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
842 if (type == XFS_DQ_USER)
843 ASSERT(ip->i_udquot == NULL);
844 else
845 ASSERT(ip->i_gdquot == NULL);
846 }
847#endif
848 mutex_lock(&h->qh_lock);
849
850 /*
851 * Look in the cache (hashtable).
852 * The chain is kept locked during lookup.
853 */
854 if (xfs_qm_dqlookup(mp, id, h, O_dqpp) == 0) {
855 XQM_STATS_INC(xqmstats.xs_qm_dqcachehits);
856 /*
857 * The dquot was found, moved to the front of the chain,
858 * taken off the freelist if it was on it, and locked
859 * at this point. Just unlock the hashchain and return.
860 */
861 ASSERT(*O_dqpp);
862 ASSERT(XFS_DQ_IS_LOCKED(*O_dqpp));
863 mutex_unlock(&h->qh_lock);
864 trace_xfs_dqget_hit(*O_dqpp);
865 return (0); /* success */
866 }
867 XQM_STATS_INC(xqmstats.xs_qm_dqcachemisses);
868
869 /*
870 * Dquot cache miss. We don't want to keep the inode lock across
871 * a (potential) disk read. Also we don't want to deal with the lock
872 * ordering between quotainode and this inode. OTOH, dropping the inode
873 * lock here means dealing with a chown that can happen before
874 * we re-acquire the lock.
875 */
876 if (ip)
877 xfs_iunlock(ip, XFS_ILOCK_EXCL);
878 /*
879 * Save the hashchain version stamp, and unlock the chain, so that
880 * we don't keep the lock across a disk read
881 */
882 version = h->qh_version;
883 mutex_unlock(&h->qh_lock);
884
885 /*
886 * Allocate the dquot on the kernel heap, and read the ondisk
887 * portion off the disk. Also, do all the necessary initialization
888 * This can return ENOENT if dquot didn't exist on disk and we didn't
889 * ask it to allocate; ESRCH if quotas got turned off suddenly.
890 */
891 if ((error = xfs_qm_idtodq(mp, id, type,
892 flags & (XFS_QMOPT_DQALLOC|XFS_QMOPT_DQREPAIR|
893 XFS_QMOPT_DOWARN),
894 &dqp))) {
895 if (ip)
896 xfs_ilock(ip, XFS_ILOCK_EXCL);
897 return (error);
898 }
899
900 /*
901 * See if this is mount code calling to look at the overall quota limits
902 * which are stored in the id == 0 user or group's dquot.
903 * Since we may not have done a quotacheck by this point, just return
904 * the dquot without attaching it to any hashtables, lists, etc, or even
905 * taking a reference.
906 * The caller must dqdestroy this once done.
907 */
908 if (flags & XFS_QMOPT_DQSUSER) {
909 ASSERT(id == 0);
910 ASSERT(! ip);
911 goto dqret;
912 }
913
914 /*
915 * Dquot lock comes after hashlock in the lock ordering
916 */
917 if (ip) {
918 xfs_ilock(ip, XFS_ILOCK_EXCL);
919
920 /*
921 * A dquot could be attached to this inode by now, since
922 * we had dropped the ilock.
923 */
924 if (type == XFS_DQ_USER) {
925 if (!XFS_IS_UQUOTA_ON(mp)) {
926 /* inode stays locked on return */
927 xfs_qm_dqdestroy(dqp);
928 return XFS_ERROR(ESRCH);
929 }
930 if (ip->i_udquot) {
931 xfs_qm_dqdestroy(dqp);
932 dqp = ip->i_udquot;
933 xfs_dqlock(dqp);
934 goto dqret;
935 }
936 } else {
937 if (!XFS_IS_OQUOTA_ON(mp)) {
938 /* inode stays locked on return */
939 xfs_qm_dqdestroy(dqp);
940 return XFS_ERROR(ESRCH);
941 }
942 if (ip->i_gdquot) {
943 xfs_qm_dqdestroy(dqp);
944 dqp = ip->i_gdquot;
945 xfs_dqlock(dqp);
946 goto dqret;
947 }
948 }
949 }
950
951 /*
952 * Hashlock comes after ilock in lock order
953 */
954 mutex_lock(&h->qh_lock);
955 if (version != h->qh_version) {
956 xfs_dquot_t *tmpdqp;
957 /*
958 * Now, see if somebody else put the dquot in the
959 * hashtable before us. This can happen because we didn't
960 * keep the hashchain lock. We don't have to worry about
961 * lock order between the two dquots here since dqp isn't
962 * on any findable lists yet.
963 */
964 if (xfs_qm_dqlookup(mp, id, h, &tmpdqp) == 0) {
965 /*
966 * Duplicate found. Just throw away the new dquot
967 * and start over.
968 */
969 xfs_qm_dqput(tmpdqp);
970 mutex_unlock(&h->qh_lock);
971 xfs_qm_dqdestroy(dqp);
972 XQM_STATS_INC(xqmstats.xs_qm_dquot_dups);
973 goto again;
974 }
975 }
976
977 /*
978 * Put the dquot at the beginning of the hash-chain and mp's list
979 * LOCK ORDER: hashlock, freelistlock, mplistlock, udqlock, gdqlock ..
980 */
981 ASSERT(mutex_is_locked(&h->qh_lock));
982 dqp->q_hash = h;
983 list_add(&dqp->q_hashlist, &h->qh_list);
984 h->qh_version++;
985
986 /*
987 * Attach this dquot to this filesystem's list of all dquots,
988 * kept inside the mount structure in m_quotainfo field
989 */
990 mutex_lock(&mp->m_quotainfo->qi_dqlist_lock);
991
992 /*
993 * We return a locked dquot to the caller, with a reference taken
994 */
995 xfs_dqlock(dqp);
996 dqp->q_nrefs = 1;
997
998 list_add(&dqp->q_mplist, &mp->m_quotainfo->qi_dqlist);
999 mp->m_quotainfo->qi_dquots++;
1000 mutex_unlock(&mp->m_quotainfo->qi_dqlist_lock);
1001 mutex_unlock(&h->qh_lock);
1002 dqret:
1003 ASSERT((ip == NULL) || xfs_isilocked(ip, XFS_ILOCK_EXCL));
1004 trace_xfs_dqget_miss(dqp);
1005 *O_dqpp = dqp;
1006 return (0);
1007}
1008
1009
1010/*
1011 * Release a reference to the dquot (decrement ref-count)
1012 * and unlock it. If there is a group quota attached to this
1013 * dquot, carefully release that too without tripping over
1014 * deadlocks'n'stuff.
1015 */
1016void
1017xfs_qm_dqput(
1018 xfs_dquot_t *dqp)
1019{
1020 xfs_dquot_t *gdqp;
1021
1022 ASSERT(dqp->q_nrefs > 0);
1023 ASSERT(XFS_DQ_IS_LOCKED(dqp));
1024
1025 trace_xfs_dqput(dqp);
1026
1027 if (dqp->q_nrefs != 1) {
1028 dqp->q_nrefs--;
1029 xfs_dqunlock(dqp);
1030 return;
1031 }
1032
1033 /*
1034 * drop the dqlock and acquire the freelist and dqlock
1035 * in the right order; but try to get it out-of-order first
1036 */
1037 if (!mutex_trylock(&xfs_Gqm->qm_dqfrlist_lock)) {
1038 trace_xfs_dqput_wait(dqp);
1039 xfs_dqunlock(dqp);
1040 mutex_lock(&xfs_Gqm->qm_dqfrlist_lock);
1041 xfs_dqlock(dqp);
1042 }
1043
1044 while (1) {
1045 gdqp = NULL;
1046
1047 /* We can't depend on nrefs being == 1 here */
1048 if (--dqp->q_nrefs == 0) {
1049 trace_xfs_dqput_free(dqp);
1050
1051 list_add_tail(&dqp->q_freelist, &xfs_Gqm->qm_dqfrlist);
1052 xfs_Gqm->qm_dqfrlist_cnt++;
1053
1054 /*
1055 * If we just added a udquot to the freelist, then
1056 * we want to release the gdquot reference that
1057 * it (probably) has. Otherwise it'll keep the
1058 * gdquot from getting reclaimed.
1059 */
1060 if ((gdqp = dqp->q_gdquot)) {
1061 /*
1062 * Avoid a recursive dqput call
1063 */
1064 xfs_dqlock(gdqp);
1065 dqp->q_gdquot = NULL;
1066 }
1067 }
1068 xfs_dqunlock(dqp);
1069
1070 /*
1071 * If we had a group quota inside the user quota as a hint,
1072 * release it now.
1073 */
1074 if (! gdqp)
1075 break;
1076 dqp = gdqp;
1077 }
1078 mutex_unlock(&xfs_Gqm->qm_dqfrlist_lock);
1079}
1080
1081/*
1082 * Release a dquot. Flush it if dirty, then dqput() it.
1083 * dquot must not be locked.
1084 */
1085void
1086xfs_qm_dqrele(
1087 xfs_dquot_t *dqp)
1088{
1089 if (!dqp)
1090 return;
1091
1092 trace_xfs_dqrele(dqp);
1093
1094 xfs_dqlock(dqp);
1095 /*
1096 * We don't care to flush it if the dquot is dirty here.
1097 * That will create stutters that we want to avoid.
1098 * Instead we do a delayed write when we try to reclaim
1099 * a dirty dquot. Also xfs_sync will take part of the burden...
1100 */
1101 xfs_qm_dqput(dqp);
1102}
1103
1104/*
1105 * This is the dquot flushing I/O completion routine. It is called
1106 * from interrupt level when the buffer containing the dquot is
1107 * flushed to disk. It is responsible for removing the dquot logitem
1108 * from the AIL if it has not been re-logged, and unlocking the dquot's
1109 * flush lock. This behavior is very similar to that of inodes..
1110 */
1111STATIC void
1112xfs_qm_dqflush_done(
1113 struct xfs_buf *bp,
1114 struct xfs_log_item *lip)
1115{
1116 xfs_dq_logitem_t *qip = (struct xfs_dq_logitem *)lip;
1117 xfs_dquot_t *dqp = qip->qli_dquot;
1118 struct xfs_ail *ailp = lip->li_ailp;
1119
1120 /*
1121 * We only want to pull the item from the AIL if its
1122 * location in the log has not changed since we started the flush.
1123 * Thus, we only bother if the dquot's lsn has
1124 * not changed. First we check the lsn outside the lock
1125 * since it's cheaper, and then we recheck while
1126 * holding the lock before removing the dquot from the AIL.
1127 */
1128 if ((lip->li_flags & XFS_LI_IN_AIL) &&
1129 lip->li_lsn == qip->qli_flush_lsn) {
1130
1131 /* xfs_trans_ail_delete() drops the AIL lock. */
1132 spin_lock(&ailp->xa_lock);
1133 if (lip->li_lsn == qip->qli_flush_lsn)
1134 xfs_trans_ail_delete(ailp, lip);
1135 else
1136 spin_unlock(&ailp->xa_lock);
1137 }
1138
1139 /*
1140 * Release the dq's flush lock since we're done with it.
1141 */
1142 xfs_dqfunlock(dqp);
1143}
1144
1145/*
1146 * Write a modified dquot to disk.
1147 * The dquot must be locked and the flush lock too taken by caller.
1148 * The flush lock will not be unlocked until the dquot reaches the disk,
1149 * but the dquot is free to be unlocked and modified by the caller
1150 * in the interim. Dquot is still locked on return. This behavior is
1151 * identical to that of inodes.
1152 */
1153int
1154xfs_qm_dqflush(
1155 xfs_dquot_t *dqp,
1156 uint flags)
1157{
1158 struct xfs_mount *mp = dqp->q_mount;
1159 struct xfs_buf *bp;
1160 struct xfs_disk_dquot *ddqp;
1161 int error;
1162
1163 ASSERT(XFS_DQ_IS_LOCKED(dqp));
1164 ASSERT(!completion_done(&dqp->q_flush));
1165
1166 trace_xfs_dqflush(dqp);
1167
1168 /*
1169 * If not dirty, or it's pinned and we are not supposed to block, nada.
1170 */
1171 if (!XFS_DQ_IS_DIRTY(dqp) ||
1172 (!(flags & SYNC_WAIT) && atomic_read(&dqp->q_pincount) > 0)) {
1173 xfs_dqfunlock(dqp);
1174 return 0;
1175 }
1176 xfs_qm_dqunpin_wait(dqp);
1177
1178 /*
1179 * This may have been unpinned because the filesystem is shutting
1180 * down forcibly. If that's the case we must not write this dquot
1181 * to disk, because the log record didn't make it to disk!
1182 */
1183 if (XFS_FORCED_SHUTDOWN(mp)) {
1184 dqp->dq_flags &= ~XFS_DQ_DIRTY;
1185 xfs_dqfunlock(dqp);
1186 return XFS_ERROR(EIO);
1187 }
1188
1189 /*
1190 * Get the buffer containing the on-disk dquot
1191 */
1192 error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, dqp->q_blkno,
1193 mp->m_quotainfo->qi_dqchunklen, 0, &bp);
1194 if (error) {
1195 ASSERT(error != ENOENT);
1196 xfs_dqfunlock(dqp);
1197 return error;
1198 }
1199
1200 /*
1201 * Calculate the location of the dquot inside the buffer.
1202 */
1203 ddqp = bp->b_addr + dqp->q_bufoffset;
1204
1205 /*
1206 * A simple sanity check in case we got a corrupted dquot..
1207 */
1208 error = xfs_qm_dqcheck(mp, &dqp->q_core, be32_to_cpu(ddqp->d_id), 0,
1209 XFS_QMOPT_DOWARN, "dqflush (incore copy)");
1210 if (error) {
1211 xfs_buf_relse(bp);
1212 xfs_dqfunlock(dqp);
1213 xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1214 return XFS_ERROR(EIO);
1215 }
1216
1217 /* This is the only portion of data that needs to persist */
1218 memcpy(ddqp, &dqp->q_core, sizeof(xfs_disk_dquot_t));
1219
1220 /*
1221 * Clear the dirty field and remember the flush lsn for later use.
1222 */
1223 dqp->dq_flags &= ~XFS_DQ_DIRTY;
1224
1225 xfs_trans_ail_copy_lsn(mp->m_ail, &dqp->q_logitem.qli_flush_lsn,
1226 &dqp->q_logitem.qli_item.li_lsn);
1227
1228 /*
1229 * Attach an iodone routine so that we can remove this dquot from the
1230 * AIL and release the flush lock once the dquot is synced to disk.
1231 */
1232 xfs_buf_attach_iodone(bp, xfs_qm_dqflush_done,
1233 &dqp->q_logitem.qli_item);
1234
1235 /*
1236 * If the buffer is pinned then push on the log so we won't
1237 * get stuck waiting in the write for too long.
1238 */
1239 if (xfs_buf_ispinned(bp)) {
1240 trace_xfs_dqflush_force(dqp);
1241 xfs_log_force(mp, 0);
1242 }
1243
1244 if (flags & SYNC_WAIT)
1245 error = xfs_bwrite(mp, bp);
1246 else
1247 xfs_bdwrite(mp, bp);
1248
1249 trace_xfs_dqflush_done(dqp);
1250
1251 /*
1252 * dqp is still locked, but caller is free to unlock it now.
1253 */
1254 return error;
1255
1256}
1257
1258int
1259xfs_qm_dqlock_nowait(
1260 xfs_dquot_t *dqp)
1261{
1262 return mutex_trylock(&dqp->q_qlock);
1263}
1264
1265void
1266xfs_dqlock(
1267 xfs_dquot_t *dqp)
1268{
1269 mutex_lock(&dqp->q_qlock);
1270}
1271
1272void
1273xfs_dqunlock(
1274 xfs_dquot_t *dqp)
1275{
1276 mutex_unlock(&(dqp->q_qlock));
1277 if (dqp->q_logitem.qli_dquot == dqp) {
1278 /* Once was dqp->q_mount, but might just have been cleared */
1279 xfs_trans_unlocked_item(dqp->q_logitem.qli_item.li_ailp,
1280 (xfs_log_item_t*)&(dqp->q_logitem));
1281 }
1282}
1283
1284
1285void
1286xfs_dqunlock_nonotify(
1287 xfs_dquot_t *dqp)
1288{
1289 mutex_unlock(&(dqp->q_qlock));
1290}
1291
1292/*
1293 * Lock two xfs_dquot structures.
1294 *
1295 * To avoid deadlocks we always lock the quota structure with
1296 * the lowerd id first.
1297 */
1298void
1299xfs_dqlock2(
1300 xfs_dquot_t *d1,
1301 xfs_dquot_t *d2)
1302{
1303 if (d1 && d2) {
1304 ASSERT(d1 != d2);
1305 if (be32_to_cpu(d1->q_core.d_id) >
1306 be32_to_cpu(d2->q_core.d_id)) {
1307 mutex_lock(&d2->q_qlock);
1308 mutex_lock_nested(&d1->q_qlock, XFS_QLOCK_NESTED);
1309 } else {
1310 mutex_lock(&d1->q_qlock);
1311 mutex_lock_nested(&d2->q_qlock, XFS_QLOCK_NESTED);
1312 }
1313 } else if (d1) {
1314 mutex_lock(&d1->q_qlock);
1315 } else if (d2) {
1316 mutex_lock(&d2->q_qlock);
1317 }
1318}
1319
1320
1321/*
1322 * Take a dquot out of the mount's dqlist as well as the hashlist.
1323 * This is called via unmount as well as quotaoff, and the purge
1324 * will always succeed unless there are soft (temp) references
1325 * outstanding.
1326 *
1327 * This returns 0 if it was purged, 1 if it wasn't. It's not an error code
1328 * that we're returning! XXXsup - not cool.
1329 */
1330/* ARGSUSED */
1331int
1332xfs_qm_dqpurge(
1333 xfs_dquot_t *dqp)
1334{
1335 xfs_dqhash_t *qh = dqp->q_hash;
1336 xfs_mount_t *mp = dqp->q_mount;
1337
1338 ASSERT(mutex_is_locked(&mp->m_quotainfo->qi_dqlist_lock));
1339 ASSERT(mutex_is_locked(&dqp->q_hash->qh_lock));
1340
1341 xfs_dqlock(dqp);
1342 /*
1343 * We really can't afford to purge a dquot that is
1344 * referenced, because these are hard refs.
1345 * It shouldn't happen in general because we went thru _all_ inodes in
1346 * dqrele_all_inodes before calling this and didn't let the mountlock go.
1347 * However it is possible that we have dquots with temporary
1348 * references that are not attached to an inode. e.g. see xfs_setattr().
1349 */
1350 if (dqp->q_nrefs != 0) {
1351 xfs_dqunlock(dqp);
1352 mutex_unlock(&dqp->q_hash->qh_lock);
1353 return (1);
1354 }
1355
1356 ASSERT(!list_empty(&dqp->q_freelist));
1357
1358 /*
1359 * If we're turning off quotas, we have to make sure that, for
1360 * example, we don't delete quota disk blocks while dquots are
1361 * in the process of getting written to those disk blocks.
1362 * This dquot might well be on AIL, and we can't leave it there
1363 * if we're turning off quotas. Basically, we need this flush
1364 * lock, and are willing to block on it.
1365 */
1366 if (!xfs_dqflock_nowait(dqp)) {
1367 /*
1368 * Block on the flush lock after nudging dquot buffer,
1369 * if it is incore.
1370 */
1371 xfs_qm_dqflock_pushbuf_wait(dqp);
1372 }
1373
1374 /*
1375 * XXXIf we're turning this type of quotas off, we don't care
1376 * about the dirty metadata sitting in this dquot. OTOH, if
1377 * we're unmounting, we do care, so we flush it and wait.
1378 */
1379 if (XFS_DQ_IS_DIRTY(dqp)) {
1380 int error;
1381
1382 /* dqflush unlocks dqflock */
1383 /*
1384 * Given that dqpurge is a very rare occurrence, it is OK
1385 * that we're holding the hashlist and mplist locks
1386 * across the disk write. But, ... XXXsup
1387 *
1388 * We don't care about getting disk errors here. We need
1389 * to purge this dquot anyway, so we go ahead regardless.
1390 */
1391 error = xfs_qm_dqflush(dqp, SYNC_WAIT);
1392 if (error)
1393 xfs_warn(mp, "%s: dquot %p flush failed",
1394 __func__, dqp);
1395 xfs_dqflock(dqp);
1396 }
1397 ASSERT(atomic_read(&dqp->q_pincount) == 0);
1398 ASSERT(XFS_FORCED_SHUTDOWN(mp) ||
1399 !(dqp->q_logitem.qli_item.li_flags & XFS_LI_IN_AIL));
1400
1401 list_del_init(&dqp->q_hashlist);
1402 qh->qh_version++;
1403 list_del_init(&dqp->q_mplist);
1404 mp->m_quotainfo->qi_dqreclaims++;
1405 mp->m_quotainfo->qi_dquots--;
1406 /*
1407 * XXX Move this to the front of the freelist, if we can get the
1408 * freelist lock.
1409 */
1410 ASSERT(!list_empty(&dqp->q_freelist));
1411
1412 dqp->q_mount = NULL;
1413 dqp->q_hash = NULL;
1414 dqp->dq_flags = XFS_DQ_INACTIVE;
1415 memset(&dqp->q_core, 0, sizeof(dqp->q_core));
1416 xfs_dqfunlock(dqp);
1417 xfs_dqunlock(dqp);
1418 mutex_unlock(&qh->qh_lock);
1419 return (0);
1420}
1421
1422
1423/*
1424 * Give the buffer a little push if it is incore and
1425 * wait on the flush lock.
1426 */
1427void
1428xfs_qm_dqflock_pushbuf_wait(
1429 xfs_dquot_t *dqp)
1430{
1431 xfs_mount_t *mp = dqp->q_mount;
1432 xfs_buf_t *bp;
1433
1434 /*
1435 * Check to see if the dquot has been flushed delayed
1436 * write. If so, grab its buffer and send it
1437 * out immediately. We'll be able to acquire
1438 * the flush lock when the I/O completes.
1439 */
1440 bp = xfs_incore(mp->m_ddev_targp, dqp->q_blkno,
1441 mp->m_quotainfo->qi_dqchunklen, XBF_TRYLOCK);
1442 if (!bp)
1443 goto out_lock;
1444
1445 if (XFS_BUF_ISDELAYWRITE(bp)) {
1446 if (xfs_buf_ispinned(bp))
1447 xfs_log_force(mp, 0);
1448 xfs_buf_delwri_promote(bp);
1449 wake_up_process(bp->b_target->bt_task);
1450 }
1451 xfs_buf_relse(bp);
1452out_lock:
1453 xfs_dqflock(dqp);
1454}
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-27 05:22:40 -0500