Merge branch 'for-2.6.30' into for-2.6.31
[linux-2.6] / fs / gfs2 / quota.c
1 /*
2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3  * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
4  *
5  * This copyrighted material is made available to anyone wishing to use,
6  * modify, copy, or redistribute it subject to the terms and conditions
7  * of the GNU General Public License version 2.
8  */
9
10 /*
11  * Quota change tags are associated with each transaction that allocates or
12  * deallocates space.  Those changes are accumulated locally to each node (in a
13  * per-node file) and then are periodically synced to the quota file.  This
14  * avoids the bottleneck of constantly touching the quota file, but introduces
15  * fuzziness in the current usage value of IDs that are being used on different
16  * nodes in the cluster simultaneously.  So, it is possible for a user on
17  * multiple nodes to overrun their quota, but that overrun is controlable.
18  * Since quota tags are part of transactions, there is no need to a quota check
19  * program to be run on node crashes or anything like that.
20  *
21  * There are couple of knobs that let the administrator manage the quota
22  * fuzziness.  "quota_quantum" sets the maximum time a quota change can be
23  * sitting on one node before being synced to the quota file.  (The default is
24  * 60 seconds.)  Another knob, "quota_scale" controls how quickly the frequency
25  * of quota file syncs increases as the user moves closer to their limit.  The
26  * more frequent the syncs, the more accurate the quota enforcement, but that
27  * means that there is more contention between the nodes for the quota file.
28  * The default value is one.  This sets the maximum theoretical quota overrun
29  * (with infinite node with infinite bandwidth) to twice the user's limit.  (In
30  * practice, the maximum overrun you see should be much less.)  A "quota_scale"
31  * number greater than one makes quota syncs more frequent and reduces the
32  * maximum overrun.  Numbers less than one (but greater than zero) make quota
33  * syncs less frequent.
34  *
35  * GFS quotas also use per-ID Lock Value Blocks (LVBs) to cache the contents of
36  * the quota file, so it is not being constantly read.
37  */
38
39 #include <linux/sched.h>
40 #include <linux/slab.h>
41 #include <linux/spinlock.h>
42 #include <linux/completion.h>
43 #include <linux/buffer_head.h>
44 #include <linux/sort.h>
45 #include <linux/fs.h>
46 #include <linux/bio.h>
47 #include <linux/gfs2_ondisk.h>
48 #include <linux/kthread.h>
49 #include <linux/freezer.h>
50
51 #include "gfs2.h"
52 #include "incore.h"
53 #include "bmap.h"
54 #include "glock.h"
55 #include "glops.h"
56 #include "log.h"
57 #include "meta_io.h"
58 #include "quota.h"
59 #include "rgrp.h"
60 #include "super.h"
61 #include "trans.h"
62 #include "inode.h"
63 #include "ops_address.h"
64 #include "util.h"
65
66 #define QUOTA_USER 1
67 #define QUOTA_GROUP 0
68
69 struct gfs2_quota_host {
70         u64 qu_limit;
71         u64 qu_warn;
72         s64 qu_value;
73         u32 qu_ll_next;
74 };
75
76 struct gfs2_quota_change_host {
77         u64 qc_change;
78         u32 qc_flags; /* GFS2_QCF_... */
79         u32 qc_id;
80 };
81
82 static LIST_HEAD(qd_lru_list);
83 static atomic_t qd_lru_count = ATOMIC_INIT(0);
84 static spinlock_t qd_lru_lock = SPIN_LOCK_UNLOCKED;
85
86 int gfs2_shrink_qd_memory(int nr, gfp_t gfp_mask)
87 {
88         struct gfs2_quota_data *qd;
89         struct gfs2_sbd *sdp;
90
91         if (nr == 0)
92                 goto out;
93
94         if (!(gfp_mask & __GFP_FS))
95                 return -1;
96
97         spin_lock(&qd_lru_lock);
98         while (nr && !list_empty(&qd_lru_list)) {
99                 qd = list_entry(qd_lru_list.next,
100                                 struct gfs2_quota_data, qd_reclaim);
101                 sdp = qd->qd_gl->gl_sbd;
102
103                 /* Free from the filesystem-specific list */
104                 list_del(&qd->qd_list);
105
106                 gfs2_assert_warn(sdp, !qd->qd_change);
107                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
108                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
109
110                 gfs2_glock_put(qd->qd_gl);
111                 atomic_dec(&sdp->sd_quota_count);
112
113                 /* Delete it from the common reclaim list */
114                 list_del_init(&qd->qd_reclaim);
115                 atomic_dec(&qd_lru_count);
116                 spin_unlock(&qd_lru_lock);
117                 kmem_cache_free(gfs2_quotad_cachep, qd);
118                 spin_lock(&qd_lru_lock);
119                 nr--;
120         }
121         spin_unlock(&qd_lru_lock);
122
123 out:
124         return (atomic_read(&qd_lru_count) * sysctl_vfs_cache_pressure) / 100;
125 }
126
127 static u64 qd2offset(struct gfs2_quota_data *qd)
128 {
129         u64 offset;
130
131         offset = 2 * (u64)qd->qd_id + !test_bit(QDF_USER, &qd->qd_flags);
132         offset *= sizeof(struct gfs2_quota);
133
134         return offset;
135 }
136
137 static int qd_alloc(struct gfs2_sbd *sdp, int user, u32 id,
138                     struct gfs2_quota_data **qdp)
139 {
140         struct gfs2_quota_data *qd;
141         int error;
142
143         qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
144         if (!qd)
145                 return -ENOMEM;
146
147         atomic_set(&qd->qd_count, 1);
148         qd->qd_id = id;
149         if (user)
150                 set_bit(QDF_USER, &qd->qd_flags);
151         qd->qd_slot = -1;
152         INIT_LIST_HEAD(&qd->qd_reclaim);
153
154         error = gfs2_glock_get(sdp, 2 * (u64)id + !user,
155                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
156         if (error)
157                 goto fail;
158
159         *qdp = qd;
160
161         return 0;
162
163 fail:
164         kmem_cache_free(gfs2_quotad_cachep, qd);
165         return error;
166 }
167
168 static int qd_get(struct gfs2_sbd *sdp, int user, u32 id, int create,
169                   struct gfs2_quota_data **qdp)
170 {
171         struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
172         int error, found;
173
174         *qdp = NULL;
175
176         for (;;) {
177                 found = 0;
178                 spin_lock(&qd_lru_lock);
179                 list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
180                         if (qd->qd_id == id &&
181                             !test_bit(QDF_USER, &qd->qd_flags) == !user) {
182                                 if (!atomic_read(&qd->qd_count) &&
183                                     !list_empty(&qd->qd_reclaim)) {
184                                         /* Remove it from reclaim list */
185                                         list_del_init(&qd->qd_reclaim);
186                                         atomic_dec(&qd_lru_count);
187                                 }
188                                 atomic_inc(&qd->qd_count);
189                                 found = 1;
190                                 break;
191                         }
192                 }
193
194                 if (!found)
195                         qd = NULL;
196
197                 if (!qd && new_qd) {
198                         qd = new_qd;
199                         list_add(&qd->qd_list, &sdp->sd_quota_list);
200                         atomic_inc(&sdp->sd_quota_count);
201                         new_qd = NULL;
202                 }
203
204                 spin_unlock(&qd_lru_lock);
205
206                 if (qd || !create) {
207                         if (new_qd) {
208                                 gfs2_glock_put(new_qd->qd_gl);
209                                 kmem_cache_free(gfs2_quotad_cachep, new_qd);
210                         }
211                         *qdp = qd;
212                         return 0;
213                 }
214
215                 error = qd_alloc(sdp, user, id, &new_qd);
216                 if (error)
217                         return error;
218         }
219 }
220
221 static void qd_hold(struct gfs2_quota_data *qd)
222 {
223         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
224         gfs2_assert(sdp, atomic_read(&qd->qd_count));
225         atomic_inc(&qd->qd_count);
226 }
227
228 static void qd_put(struct gfs2_quota_data *qd)
229 {
230         if (atomic_dec_and_lock(&qd->qd_count, &qd_lru_lock)) {
231                 /* Add to the reclaim list */
232                 list_add_tail(&qd->qd_reclaim, &qd_lru_list);
233                 atomic_inc(&qd_lru_count);
234                 spin_unlock(&qd_lru_lock);
235         }
236 }
237
238 static int slot_get(struct gfs2_quota_data *qd)
239 {
240         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
241         unsigned int c, o = 0, b;
242         unsigned char byte = 0;
243
244         spin_lock(&qd_lru_lock);
245
246         if (qd->qd_slot_count++) {
247                 spin_unlock(&qd_lru_lock);
248                 return 0;
249         }
250
251         for (c = 0; c < sdp->sd_quota_chunks; c++)
252                 for (o = 0; o < PAGE_SIZE; o++) {
253                         byte = sdp->sd_quota_bitmap[c][o];
254                         if (byte != 0xFF)
255                                 goto found;
256                 }
257
258         goto fail;
259
260 found:
261         for (b = 0; b < 8; b++)
262                 if (!(byte & (1 << b)))
263                         break;
264         qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
265
266         if (qd->qd_slot >= sdp->sd_quota_slots)
267                 goto fail;
268
269         sdp->sd_quota_bitmap[c][o] |= 1 << b;
270
271         spin_unlock(&qd_lru_lock);
272
273         return 0;
274
275 fail:
276         qd->qd_slot_count--;
277         spin_unlock(&qd_lru_lock);
278         return -ENOSPC;
279 }
280
281 static void slot_hold(struct gfs2_quota_data *qd)
282 {
283         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
284
285         spin_lock(&qd_lru_lock);
286         gfs2_assert(sdp, qd->qd_slot_count);
287         qd->qd_slot_count++;
288         spin_unlock(&qd_lru_lock);
289 }
290
291 static void slot_put(struct gfs2_quota_data *qd)
292 {
293         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
294
295         spin_lock(&qd_lru_lock);
296         gfs2_assert(sdp, qd->qd_slot_count);
297         if (!--qd->qd_slot_count) {
298                 gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
299                 qd->qd_slot = -1;
300         }
301         spin_unlock(&qd_lru_lock);
302 }
303
304 static int bh_get(struct gfs2_quota_data *qd)
305 {
306         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
307         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
308         unsigned int block, offset;
309         struct buffer_head *bh;
310         int error;
311         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
312
313         mutex_lock(&sdp->sd_quota_mutex);
314
315         if (qd->qd_bh_count++) {
316                 mutex_unlock(&sdp->sd_quota_mutex);
317                 return 0;
318         }
319
320         block = qd->qd_slot / sdp->sd_qc_per_block;
321         offset = qd->qd_slot % sdp->sd_qc_per_block;
322
323         bh_map.b_size = 1 << ip->i_inode.i_blkbits;
324         error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
325         if (error)
326                 goto fail;
327         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
328         if (error)
329                 goto fail;
330         error = -EIO;
331         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
332                 goto fail_brelse;
333
334         qd->qd_bh = bh;
335         qd->qd_bh_qc = (struct gfs2_quota_change *)
336                 (bh->b_data + sizeof(struct gfs2_meta_header) +
337                  offset * sizeof(struct gfs2_quota_change));
338
339         mutex_unlock(&sdp->sd_quota_mutex);
340
341         return 0;
342
343 fail_brelse:
344         brelse(bh);
345 fail:
346         qd->qd_bh_count--;
347         mutex_unlock(&sdp->sd_quota_mutex);
348         return error;
349 }
350
351 static void bh_put(struct gfs2_quota_data *qd)
352 {
353         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
354
355         mutex_lock(&sdp->sd_quota_mutex);
356         gfs2_assert(sdp, qd->qd_bh_count);
357         if (!--qd->qd_bh_count) {
358                 brelse(qd->qd_bh);
359                 qd->qd_bh = NULL;
360                 qd->qd_bh_qc = NULL;
361         }
362         mutex_unlock(&sdp->sd_quota_mutex);
363 }
364
365 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
366 {
367         struct gfs2_quota_data *qd = NULL;
368         int error;
369         int found = 0;
370
371         *qdp = NULL;
372
373         if (sdp->sd_vfs->s_flags & MS_RDONLY)
374                 return 0;
375
376         spin_lock(&qd_lru_lock);
377
378         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
379                 if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
380                     !test_bit(QDF_CHANGE, &qd->qd_flags) ||
381                     qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
382                         continue;
383
384                 list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
385
386                 set_bit(QDF_LOCKED, &qd->qd_flags);
387                 gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
388                 atomic_inc(&qd->qd_count);
389                 qd->qd_change_sync = qd->qd_change;
390                 gfs2_assert_warn(sdp, qd->qd_slot_count);
391                 qd->qd_slot_count++;
392                 found = 1;
393
394                 break;
395         }
396
397         if (!found)
398                 qd = NULL;
399
400         spin_unlock(&qd_lru_lock);
401
402         if (qd) {
403                 gfs2_assert_warn(sdp, qd->qd_change_sync);
404                 error = bh_get(qd);
405                 if (error) {
406                         clear_bit(QDF_LOCKED, &qd->qd_flags);
407                         slot_put(qd);
408                         qd_put(qd);
409                         return error;
410                 }
411         }
412
413         *qdp = qd;
414
415         return 0;
416 }
417
418 static int qd_trylock(struct gfs2_quota_data *qd)
419 {
420         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
421
422         if (sdp->sd_vfs->s_flags & MS_RDONLY)
423                 return 0;
424
425         spin_lock(&qd_lru_lock);
426
427         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
428             !test_bit(QDF_CHANGE, &qd->qd_flags)) {
429                 spin_unlock(&qd_lru_lock);
430                 return 0;
431         }
432
433         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
434
435         set_bit(QDF_LOCKED, &qd->qd_flags);
436         gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
437         atomic_inc(&qd->qd_count);
438         qd->qd_change_sync = qd->qd_change;
439         gfs2_assert_warn(sdp, qd->qd_slot_count);
440         qd->qd_slot_count++;
441
442         spin_unlock(&qd_lru_lock);
443
444         gfs2_assert_warn(sdp, qd->qd_change_sync);
445         if (bh_get(qd)) {
446                 clear_bit(QDF_LOCKED, &qd->qd_flags);
447                 slot_put(qd);
448                 qd_put(qd);
449                 return 0;
450         }
451
452         return 1;
453 }
454
455 static void qd_unlock(struct gfs2_quota_data *qd)
456 {
457         gfs2_assert_warn(qd->qd_gl->gl_sbd,
458                          test_bit(QDF_LOCKED, &qd->qd_flags));
459         clear_bit(QDF_LOCKED, &qd->qd_flags);
460         bh_put(qd);
461         slot_put(qd);
462         qd_put(qd);
463 }
464
465 static int qdsb_get(struct gfs2_sbd *sdp, int user, u32 id, int create,
466                     struct gfs2_quota_data **qdp)
467 {
468         int error;
469
470         error = qd_get(sdp, user, id, create, qdp);
471         if (error)
472                 return error;
473
474         error = slot_get(*qdp);
475         if (error)
476                 goto fail;
477
478         error = bh_get(*qdp);
479         if (error)
480                 goto fail_slot;
481
482         return 0;
483
484 fail_slot:
485         slot_put(*qdp);
486 fail:
487         qd_put(*qdp);
488         return error;
489 }
490
491 static void qdsb_put(struct gfs2_quota_data *qd)
492 {
493         bh_put(qd);
494         slot_put(qd);
495         qd_put(qd);
496 }
497
498 int gfs2_quota_hold(struct gfs2_inode *ip, u32 uid, u32 gid)
499 {
500         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
501         struct gfs2_alloc *al = ip->i_alloc;
502         struct gfs2_quota_data **qd = al->al_qd;
503         int error;
504
505         if (gfs2_assert_warn(sdp, !al->al_qd_num) ||
506             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
507                 return -EIO;
508
509         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
510                 return 0;
511
512         error = qdsb_get(sdp, QUOTA_USER, ip->i_inode.i_uid, CREATE, qd);
513         if (error)
514                 goto out;
515         al->al_qd_num++;
516         qd++;
517
518         error = qdsb_get(sdp, QUOTA_GROUP, ip->i_inode.i_gid, CREATE, qd);
519         if (error)
520                 goto out;
521         al->al_qd_num++;
522         qd++;
523
524         if (uid != NO_QUOTA_CHANGE && uid != ip->i_inode.i_uid) {
525                 error = qdsb_get(sdp, QUOTA_USER, uid, CREATE, qd);
526                 if (error)
527                         goto out;
528                 al->al_qd_num++;
529                 qd++;
530         }
531
532         if (gid != NO_QUOTA_CHANGE && gid != ip->i_inode.i_gid) {
533                 error = qdsb_get(sdp, QUOTA_GROUP, gid, CREATE, qd);
534                 if (error)
535                         goto out;
536                 al->al_qd_num++;
537                 qd++;
538         }
539
540 out:
541         if (error)
542                 gfs2_quota_unhold(ip);
543         return error;
544 }
545
546 void gfs2_quota_unhold(struct gfs2_inode *ip)
547 {
548         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
549         struct gfs2_alloc *al = ip->i_alloc;
550         unsigned int x;
551
552         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
553
554         for (x = 0; x < al->al_qd_num; x++) {
555                 qdsb_put(al->al_qd[x]);
556                 al->al_qd[x] = NULL;
557         }
558         al->al_qd_num = 0;
559 }
560
561 static int sort_qd(const void *a, const void *b)
562 {
563         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
564         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
565
566         if (!test_bit(QDF_USER, &qd_a->qd_flags) !=
567             !test_bit(QDF_USER, &qd_b->qd_flags)) {
568                 if (test_bit(QDF_USER, &qd_a->qd_flags))
569                         return -1;
570                 else
571                         return 1;
572         }
573         if (qd_a->qd_id < qd_b->qd_id)
574                 return -1;
575         if (qd_a->qd_id > qd_b->qd_id)
576                 return 1;
577
578         return 0;
579 }
580
581 static void do_qc(struct gfs2_quota_data *qd, s64 change)
582 {
583         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
584         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
585         struct gfs2_quota_change *qc = qd->qd_bh_qc;
586         s64 x;
587
588         mutex_lock(&sdp->sd_quota_mutex);
589         gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
590
591         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
592                 qc->qc_change = 0;
593                 qc->qc_flags = 0;
594                 if (test_bit(QDF_USER, &qd->qd_flags))
595                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
596                 qc->qc_id = cpu_to_be32(qd->qd_id);
597         }
598
599         x = be64_to_cpu(qc->qc_change) + change;
600         qc->qc_change = cpu_to_be64(x);
601
602         spin_lock(&qd_lru_lock);
603         qd->qd_change = x;
604         spin_unlock(&qd_lru_lock);
605
606         if (!x) {
607                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
608                 clear_bit(QDF_CHANGE, &qd->qd_flags);
609                 qc->qc_flags = 0;
610                 qc->qc_id = 0;
611                 slot_put(qd);
612                 qd_put(qd);
613         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
614                 qd_hold(qd);
615                 slot_hold(qd);
616         }
617
618         mutex_unlock(&sdp->sd_quota_mutex);
619 }
620
621 static void gfs2_quota_in(struct gfs2_quota_host *qu, const void *buf)
622 {
623         const struct gfs2_quota *str = buf;
624
625         qu->qu_limit = be64_to_cpu(str->qu_limit);
626         qu->qu_warn = be64_to_cpu(str->qu_warn);
627         qu->qu_value = be64_to_cpu(str->qu_value);
628         qu->qu_ll_next = be32_to_cpu(str->qu_ll_next);
629 }
630
631 static void gfs2_quota_out(const struct gfs2_quota_host *qu, void *buf)
632 {
633         struct gfs2_quota *str = buf;
634
635         str->qu_limit = cpu_to_be64(qu->qu_limit);
636         str->qu_warn = cpu_to_be64(qu->qu_warn);
637         str->qu_value = cpu_to_be64(qu->qu_value);
638         str->qu_ll_next = cpu_to_be32(qu->qu_ll_next);
639         memset(&str->qu_reserved, 0, sizeof(str->qu_reserved));
640 }
641
642 /**
643  * gfs2_adjust_quota
644  *
645  * This function was mostly borrowed from gfs2_block_truncate_page which was
646  * in turn mostly borrowed from ext3
647  */
648 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
649                              s64 change, struct gfs2_quota_data *qd)
650 {
651         struct inode *inode = &ip->i_inode;
652         struct address_space *mapping = inode->i_mapping;
653         unsigned long index = loc >> PAGE_CACHE_SHIFT;
654         unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
655         unsigned blocksize, iblock, pos;
656         struct buffer_head *bh;
657         struct page *page;
658         void *kaddr;
659         char *ptr;
660         struct gfs2_quota_host qp;
661         s64 value;
662         int err = -EIO;
663
664         if (gfs2_is_stuffed(ip))
665                 gfs2_unstuff_dinode(ip, NULL);
666         
667         page = grab_cache_page(mapping, index);
668         if (!page)
669                 return -ENOMEM;
670
671         blocksize = inode->i_sb->s_blocksize;
672         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
673
674         if (!page_has_buffers(page))
675                 create_empty_buffers(page, blocksize, 0);
676
677         bh = page_buffers(page);
678         pos = blocksize;
679         while (offset >= pos) {
680                 bh = bh->b_this_page;
681                 iblock++;
682                 pos += blocksize;
683         }
684
685         if (!buffer_mapped(bh)) {
686                 gfs2_block_map(inode, iblock, bh, 1);
687                 if (!buffer_mapped(bh))
688                         goto unlock;
689         }
690
691         if (PageUptodate(page))
692                 set_buffer_uptodate(bh);
693
694         if (!buffer_uptodate(bh)) {
695                 ll_rw_block(READ_META, 1, &bh);
696                 wait_on_buffer(bh);
697                 if (!buffer_uptodate(bh))
698                         goto unlock;
699         }
700
701         gfs2_trans_add_bh(ip->i_gl, bh, 0);
702
703         kaddr = kmap_atomic(page, KM_USER0);
704         ptr = kaddr + offset;
705         gfs2_quota_in(&qp, ptr);
706         qp.qu_value += change;
707         value = qp.qu_value;
708         gfs2_quota_out(&qp, ptr);
709         flush_dcache_page(page);
710         kunmap_atomic(kaddr, KM_USER0);
711         err = 0;
712         qd->qd_qb.qb_magic = cpu_to_be32(GFS2_MAGIC);
713         qd->qd_qb.qb_value = cpu_to_be64(value);
714         ((struct gfs2_quota_lvb*)(qd->qd_gl->gl_lvb))->qb_magic = cpu_to_be32(GFS2_MAGIC);
715         ((struct gfs2_quota_lvb*)(qd->qd_gl->gl_lvb))->qb_value = cpu_to_be64(value);
716 unlock:
717         unlock_page(page);
718         page_cache_release(page);
719         return err;
720 }
721
722 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
723 {
724         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
725         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
726         unsigned int data_blocks, ind_blocks;
727         struct gfs2_holder *ghs, i_gh;
728         unsigned int qx, x;
729         struct gfs2_quota_data *qd;
730         loff_t offset;
731         unsigned int nalloc = 0, blocks;
732         struct gfs2_alloc *al = NULL;
733         int error;
734
735         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
736                               &data_blocks, &ind_blocks);
737
738         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
739         if (!ghs)
740                 return -ENOMEM;
741
742         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
743         for (qx = 0; qx < num_qd; qx++) {
744                 error = gfs2_glock_nq_init(qda[qx]->qd_gl,
745                                            LM_ST_EXCLUSIVE,
746                                            GL_NOCACHE, &ghs[qx]);
747                 if (error)
748                         goto out;
749         }
750
751         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
752         if (error)
753                 goto out;
754
755         for (x = 0; x < num_qd; x++) {
756                 int alloc_required;
757
758                 offset = qd2offset(qda[x]);
759                 error = gfs2_write_alloc_required(ip, offset,
760                                                   sizeof(struct gfs2_quota),
761                                                   &alloc_required);
762                 if (error)
763                         goto out_gunlock;
764                 if (alloc_required)
765                         nalloc++;
766         }
767
768         al = gfs2_alloc_get(ip);
769         if (!al) {
770                 error = -ENOMEM;
771                 goto out_gunlock;
772         }
773         /* 
774          * 1 blk for unstuffing inode if stuffed. We add this extra
775          * block to the reservation unconditionally. If the inode
776          * doesn't need unstuffing, the block will be released to the 
777          * rgrp since it won't be allocated during the transaction
778          */
779         al->al_requested = 1;
780         /* +1 in the end for block requested above for unstuffing */
781         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 1;
782
783         if (nalloc)
784                 al->al_requested += nalloc * (data_blocks + ind_blocks);                
785         error = gfs2_inplace_reserve(ip);
786         if (error)
787                 goto out_alloc;
788
789         if (nalloc)
790                 blocks += al->al_rgd->rd_length + nalloc * ind_blocks + RES_STATFS;
791
792         error = gfs2_trans_begin(sdp, blocks, 0);
793         if (error)
794                 goto out_ipres;
795
796         for (x = 0; x < num_qd; x++) {
797                 qd = qda[x];
798                 offset = qd2offset(qd);
799                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync,
800                                           (struct gfs2_quota_data *)
801                                           qd);
802                 if (error)
803                         goto out_end_trans;
804
805                 do_qc(qd, -qd->qd_change_sync);
806         }
807
808         error = 0;
809
810 out_end_trans:
811         gfs2_trans_end(sdp);
812 out_ipres:
813         gfs2_inplace_release(ip);
814 out_alloc:
815         gfs2_alloc_put(ip);
816 out_gunlock:
817         gfs2_glock_dq_uninit(&i_gh);
818 out:
819         while (qx--)
820                 gfs2_glock_dq_uninit(&ghs[qx]);
821         kfree(ghs);
822         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
823         return error;
824 }
825
826 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
827                     struct gfs2_holder *q_gh)
828 {
829         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
830         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
831         struct gfs2_holder i_gh;
832         struct gfs2_quota_host q;
833         char buf[sizeof(struct gfs2_quota)];
834         int error;
835         struct gfs2_quota_lvb *qlvb;
836
837 restart:
838         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
839         if (error)
840                 return error;
841
842         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
843
844         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
845                 loff_t pos;
846                 gfs2_glock_dq_uninit(q_gh);
847                 error = gfs2_glock_nq_init(qd->qd_gl,
848                                            LM_ST_EXCLUSIVE, GL_NOCACHE,
849                                            q_gh);
850                 if (error)
851                         return error;
852
853                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
854                 if (error)
855                         goto fail;
856
857                 memset(buf, 0, sizeof(struct gfs2_quota));
858                 pos = qd2offset(qd);
859                 error = gfs2_internal_read(ip, NULL, buf, &pos,
860                                            sizeof(struct gfs2_quota));
861                 if (error < 0)
862                         goto fail_gunlock;
863
864                 gfs2_glock_dq_uninit(&i_gh);
865
866                 gfs2_quota_in(&q, buf);
867                 qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
868                 qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
869                 qlvb->__pad = 0;
870                 qlvb->qb_limit = cpu_to_be64(q.qu_limit);
871                 qlvb->qb_warn = cpu_to_be64(q.qu_warn);
872                 qlvb->qb_value = cpu_to_be64(q.qu_value);
873                 qd->qd_qb = *qlvb;
874
875                 if (gfs2_glock_is_blocking(qd->qd_gl)) {
876                         gfs2_glock_dq_uninit(q_gh);
877                         force_refresh = 0;
878                         goto restart;
879                 }
880         }
881
882         return 0;
883
884 fail_gunlock:
885         gfs2_glock_dq_uninit(&i_gh);
886 fail:
887         gfs2_glock_dq_uninit(q_gh);
888         return error;
889 }
890
891 int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
892 {
893         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
894         struct gfs2_alloc *al = ip->i_alloc;
895         unsigned int x;
896         int error = 0;
897
898         gfs2_quota_hold(ip, uid, gid);
899
900         if (capable(CAP_SYS_RESOURCE) ||
901             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
902                 return 0;
903
904         sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
905              sort_qd, NULL);
906
907         for (x = 0; x < al->al_qd_num; x++) {
908                 error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
909                 if (error)
910                         break;
911         }
912
913         if (!error)
914                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
915         else {
916                 while (x--)
917                         gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
918                 gfs2_quota_unhold(ip);
919         }
920
921         return error;
922 }
923
924 static int need_sync(struct gfs2_quota_data *qd)
925 {
926         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
927         struct gfs2_tune *gt = &sdp->sd_tune;
928         s64 value;
929         unsigned int num, den;
930         int do_sync = 1;
931
932         if (!qd->qd_qb.qb_limit)
933                 return 0;
934
935         spin_lock(&qd_lru_lock);
936         value = qd->qd_change;
937         spin_unlock(&qd_lru_lock);
938
939         spin_lock(&gt->gt_spin);
940         num = gt->gt_quota_scale_num;
941         den = gt->gt_quota_scale_den;
942         spin_unlock(&gt->gt_spin);
943
944         if (value < 0)
945                 do_sync = 0;
946         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
947                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
948                 do_sync = 0;
949         else {
950                 value *= gfs2_jindex_size(sdp) * num;
951                 value = div_s64(value, den);
952                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
953                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
954                         do_sync = 0;
955         }
956
957         return do_sync;
958 }
959
960 void gfs2_quota_unlock(struct gfs2_inode *ip)
961 {
962         struct gfs2_alloc *al = ip->i_alloc;
963         struct gfs2_quota_data *qda[4];
964         unsigned int count = 0;
965         unsigned int x;
966
967         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
968                 goto out;
969
970         for (x = 0; x < al->al_qd_num; x++) {
971                 struct gfs2_quota_data *qd;
972                 int sync;
973
974                 qd = al->al_qd[x];
975                 sync = need_sync(qd);
976
977                 gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
978
979                 if (sync && qd_trylock(qd))
980                         qda[count++] = qd;
981         }
982
983         if (count) {
984                 do_sync(count, qda);
985                 for (x = 0; x < count; x++)
986                         qd_unlock(qda[x]);
987         }
988
989 out:
990         gfs2_quota_unhold(ip);
991 }
992
993 #define MAX_LINE 256
994
995 static int print_message(struct gfs2_quota_data *qd, char *type)
996 {
997         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
998
999         printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\r\n",
1000                sdp->sd_fsname, type,
1001                (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
1002                qd->qd_id);
1003
1004         return 0;
1005 }
1006
1007 int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
1008 {
1009         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1010         struct gfs2_alloc *al = ip->i_alloc;
1011         struct gfs2_quota_data *qd;
1012         s64 value;
1013         unsigned int x;
1014         int error = 0;
1015
1016         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1017                 return 0;
1018
1019         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1020                 return 0;
1021
1022         for (x = 0; x < al->al_qd_num; x++) {
1023                 qd = al->al_qd[x];
1024
1025                 if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1026                       (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
1027                         continue;
1028
1029                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1030                 spin_lock(&qd_lru_lock);
1031                 value += qd->qd_change;
1032                 spin_unlock(&qd_lru_lock);
1033
1034                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
1035                         print_message(qd, "exceeded");
1036                         error = -EDQUOT;
1037                         break;
1038                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
1039                            (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
1040                            time_after_eq(jiffies, qd->qd_last_warn +
1041                                          gfs2_tune_get(sdp,
1042                                                 gt_quota_warn_period) * HZ)) {
1043                         error = print_message(qd, "warning");
1044                         qd->qd_last_warn = jiffies;
1045                 }
1046         }
1047
1048         return error;
1049 }
1050
1051 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1052                        u32 uid, u32 gid)
1053 {
1054         struct gfs2_alloc *al = ip->i_alloc;
1055         struct gfs2_quota_data *qd;
1056         unsigned int x;
1057
1058         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1059                 return;
1060         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1061                 return;
1062
1063         for (x = 0; x < al->al_qd_num; x++) {
1064                 qd = al->al_qd[x];
1065
1066                 if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1067                     (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
1068                         do_qc(qd, change);
1069                 }
1070         }
1071 }
1072
1073 int gfs2_quota_sync(struct gfs2_sbd *sdp)
1074 {
1075         struct gfs2_quota_data **qda;
1076         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
1077         unsigned int num_qd;
1078         unsigned int x;
1079         int error = 0;
1080
1081         sdp->sd_quota_sync_gen++;
1082
1083         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1084         if (!qda)
1085                 return -ENOMEM;
1086
1087         do {
1088                 num_qd = 0;
1089
1090                 for (;;) {
1091                         error = qd_fish(sdp, qda + num_qd);
1092                         if (error || !qda[num_qd])
1093                                 break;
1094                         if (++num_qd == max_qd)
1095                                 break;
1096                 }
1097
1098                 if (num_qd) {
1099                         if (!error)
1100                                 error = do_sync(num_qd, qda);
1101                         if (!error)
1102                                 for (x = 0; x < num_qd; x++)
1103                                         qda[x]->qd_sync_gen =
1104                                                 sdp->sd_quota_sync_gen;
1105
1106                         for (x = 0; x < num_qd; x++)
1107                                 qd_unlock(qda[x]);
1108                 }
1109         } while (!error && num_qd == max_qd);
1110
1111         kfree(qda);
1112
1113         return error;
1114 }
1115
1116 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
1117 {
1118         struct gfs2_quota_data *qd;
1119         struct gfs2_holder q_gh;
1120         int error;
1121
1122         error = qd_get(sdp, user, id, CREATE, &qd);
1123         if (error)
1124                 return error;
1125
1126         error = do_glock(qd, FORCE, &q_gh);
1127         if (!error)
1128                 gfs2_glock_dq_uninit(&q_gh);
1129
1130         qd_put(qd);
1131
1132         return error;
1133 }
1134
1135 static void gfs2_quota_change_in(struct gfs2_quota_change_host *qc, const void *buf)
1136 {
1137         const struct gfs2_quota_change *str = buf;
1138
1139         qc->qc_change = be64_to_cpu(str->qc_change);
1140         qc->qc_flags = be32_to_cpu(str->qc_flags);
1141         qc->qc_id = be32_to_cpu(str->qc_id);
1142 }
1143
1144 int gfs2_quota_init(struct gfs2_sbd *sdp)
1145 {
1146         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1147         unsigned int blocks = ip->i_disksize >> sdp->sd_sb.sb_bsize_shift;
1148         unsigned int x, slot = 0;
1149         unsigned int found = 0;
1150         u64 dblock;
1151         u32 extlen = 0;
1152         int error;
1153
1154         if (!ip->i_disksize || ip->i_disksize > (64 << 20) ||
1155             ip->i_disksize & (sdp->sd_sb.sb_bsize - 1)) {
1156                 gfs2_consist_inode(ip);
1157                 return -EIO;
1158         }
1159         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1160         sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1161
1162         error = -ENOMEM;
1163
1164         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1165                                        sizeof(unsigned char *), GFP_NOFS);
1166         if (!sdp->sd_quota_bitmap)
1167                 return error;
1168
1169         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1170                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_NOFS);
1171                 if (!sdp->sd_quota_bitmap[x])
1172                         goto fail;
1173         }
1174
1175         for (x = 0; x < blocks; x++) {
1176                 struct buffer_head *bh;
1177                 unsigned int y;
1178
1179                 if (!extlen) {
1180                         int new = 0;
1181                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1182                         if (error)
1183                                 goto fail;
1184                 }
1185                 error = -EIO;
1186                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1187                 if (!bh)
1188                         goto fail;
1189                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1190                         brelse(bh);
1191                         goto fail;
1192                 }
1193
1194                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1195                      y++, slot++) {
1196                         struct gfs2_quota_change_host qc;
1197                         struct gfs2_quota_data *qd;
1198
1199                         gfs2_quota_change_in(&qc, bh->b_data +
1200                                           sizeof(struct gfs2_meta_header) +
1201                                           y * sizeof(struct gfs2_quota_change));
1202                         if (!qc.qc_change)
1203                                 continue;
1204
1205                         error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1206                                          qc.qc_id, &qd);
1207                         if (error) {
1208                                 brelse(bh);
1209                                 goto fail;
1210                         }
1211
1212                         set_bit(QDF_CHANGE, &qd->qd_flags);
1213                         qd->qd_change = qc.qc_change;
1214                         qd->qd_slot = slot;
1215                         qd->qd_slot_count = 1;
1216
1217                         spin_lock(&qd_lru_lock);
1218                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1219                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1220                         atomic_inc(&sdp->sd_quota_count);
1221                         spin_unlock(&qd_lru_lock);
1222
1223                         found++;
1224                 }
1225
1226                 brelse(bh);
1227                 dblock++;
1228                 extlen--;
1229         }
1230
1231         if (found)
1232                 fs_info(sdp, "found %u quota changes\n", found);
1233
1234         return 0;
1235
1236 fail:
1237         gfs2_quota_cleanup(sdp);
1238         return error;
1239 }
1240
1241 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1242 {
1243         struct list_head *head = &sdp->sd_quota_list;
1244         struct gfs2_quota_data *qd;
1245         unsigned int x;
1246
1247         spin_lock(&qd_lru_lock);
1248         while (!list_empty(head)) {
1249                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1250
1251                 if (atomic_read(&qd->qd_count) > 1 ||
1252                     (atomic_read(&qd->qd_count) &&
1253                      !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1254                         list_move(&qd->qd_list, head);
1255                         spin_unlock(&qd_lru_lock);
1256                         schedule();
1257                         spin_lock(&qd_lru_lock);
1258                         continue;
1259                 }
1260
1261                 list_del(&qd->qd_list);
1262                 /* Also remove if this qd exists in the reclaim list */
1263                 if (!list_empty(&qd->qd_reclaim)) {
1264                         list_del_init(&qd->qd_reclaim);
1265                         atomic_dec(&qd_lru_count);
1266                 }
1267                 atomic_dec(&sdp->sd_quota_count);
1268                 spin_unlock(&qd_lru_lock);
1269
1270                 if (!atomic_read(&qd->qd_count)) {
1271                         gfs2_assert_warn(sdp, !qd->qd_change);
1272                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1273                 } else
1274                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1275                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1276
1277                 gfs2_glock_put(qd->qd_gl);
1278                 kmem_cache_free(gfs2_quotad_cachep, qd);
1279
1280                 spin_lock(&qd_lru_lock);
1281         }
1282         spin_unlock(&qd_lru_lock);
1283
1284         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1285
1286         if (sdp->sd_quota_bitmap) {
1287                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1288                         kfree(sdp->sd_quota_bitmap[x]);
1289                 kfree(sdp->sd_quota_bitmap);
1290         }
1291 }
1292
1293 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1294 {
1295         if (error == 0 || error == -EROFS)
1296                 return;
1297         if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1298                 fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1299 }
1300
1301 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1302                                int (*fxn)(struct gfs2_sbd *sdp),
1303                                unsigned long t, unsigned long *timeo,
1304                                unsigned int *new_timeo)
1305 {
1306         if (t >= *timeo) {
1307                 int error = fxn(sdp);
1308                 quotad_error(sdp, msg, error);
1309                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1310         } else {
1311                 *timeo -= t;
1312         }
1313 }
1314
1315 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1316 {
1317         struct gfs2_inode *ip;
1318
1319         while(1) {
1320                 ip = NULL;
1321                 spin_lock(&sdp->sd_trunc_lock);
1322                 if (!list_empty(&sdp->sd_trunc_list)) {
1323                         ip = list_entry(sdp->sd_trunc_list.next,
1324                                         struct gfs2_inode, i_trunc_list);
1325                         list_del_init(&ip->i_trunc_list);
1326                 }
1327                 spin_unlock(&sdp->sd_trunc_lock);
1328                 if (ip == NULL)
1329                         return;
1330                 gfs2_glock_finish_truncate(ip);
1331         }
1332 }
1333
1334 /**
1335  * gfs2_quotad - Write cached quota changes into the quota file
1336  * @sdp: Pointer to GFS2 superblock
1337  *
1338  */
1339
1340 int gfs2_quotad(void *data)
1341 {
1342         struct gfs2_sbd *sdp = data;
1343         struct gfs2_tune *tune = &sdp->sd_tune;
1344         unsigned long statfs_timeo = 0;
1345         unsigned long quotad_timeo = 0;
1346         unsigned long t = 0;
1347         DEFINE_WAIT(wait);
1348         int empty;
1349
1350         while (!kthread_should_stop()) {
1351
1352                 /* Update the master statfs file */
1353                 quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1354                                    &statfs_timeo, &tune->gt_statfs_quantum);
1355
1356                 /* Update quota file */
1357                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
1358                                    &quotad_timeo, &tune->gt_quota_quantum);
1359
1360                 /* Check for & recover partially truncated inodes */
1361                 quotad_check_trunc_list(sdp);
1362
1363                 if (freezing(current))
1364                         refrigerator();
1365                 t = min(quotad_timeo, statfs_timeo);
1366
1367                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_UNINTERRUPTIBLE);
1368                 spin_lock(&sdp->sd_trunc_lock);
1369                 empty = list_empty(&sdp->sd_trunc_list);
1370                 spin_unlock(&sdp->sd_trunc_lock);
1371                 if (empty)
1372                         t -= schedule_timeout(t);
1373                 else
1374                         t = 0;
1375                 finish_wait(&sdp->sd_quota_wait, &wait);
1376         }
1377
1378         return 0;
1379 }
1380