Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wirel...
[linux-drm-fsl-dcu.git] / 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 for 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/mm.h>
42 #include <linux/spinlock.h>
43 #include <linux/completion.h>
44 #include <linux/buffer_head.h>
45 #include <linux/sort.h>
46 #include <linux/fs.h>
47 #include <linux/bio.h>
48 #include <linux/gfs2_ondisk.h>
49 #include <linux/kthread.h>
50 #include <linux/freezer.h>
51 #include <linux/quota.h>
52 #include <linux/dqblk_xfs.h>
53 #include <linux/lockref.h>
54 #include <linux/list_lru.h>
55
56 #include "gfs2.h"
57 #include "incore.h"
58 #include "bmap.h"
59 #include "glock.h"
60 #include "glops.h"
61 #include "log.h"
62 #include "meta_io.h"
63 #include "quota.h"
64 #include "rgrp.h"
65 #include "super.h"
66 #include "trans.h"
67 #include "inode.h"
68 #include "util.h"
69
70 struct gfs2_quota_change_host {
71         u64 qc_change;
72         u32 qc_flags; /* GFS2_QCF_... */
73         struct kqid qc_id;
74 };
75
76 /* Lock order: qd_lock -> qd->lockref.lock -> lru lock */
77 static DEFINE_SPINLOCK(qd_lock);
78 struct list_lru gfs2_qd_lru;
79
80 static void gfs2_qd_dispose(struct list_head *list)
81 {
82         struct gfs2_quota_data *qd;
83         struct gfs2_sbd *sdp;
84
85         while (!list_empty(list)) {
86                 qd = list_entry(list->next, struct gfs2_quota_data, qd_lru);
87                 sdp = qd->qd_gl->gl_sbd;
88
89                 list_del(&qd->qd_lru);
90
91                 /* Free from the filesystem-specific list */
92                 spin_lock(&qd_lock);
93                 list_del(&qd->qd_list);
94                 spin_unlock(&qd_lock);
95
96                 gfs2_assert_warn(sdp, !qd->qd_change);
97                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
98                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
99
100                 gfs2_glock_put(qd->qd_gl);
101                 atomic_dec(&sdp->sd_quota_count);
102
103                 /* Delete it from the common reclaim list */
104                 kmem_cache_free(gfs2_quotad_cachep, qd);
105         }
106 }
107
108
109 static enum lru_status gfs2_qd_isolate(struct list_head *item, spinlock_t *lock, void *arg)
110 {
111         struct list_head *dispose = arg;
112         struct gfs2_quota_data *qd = list_entry(item, struct gfs2_quota_data, qd_lru);
113
114         if (!spin_trylock(&qd->qd_lockref.lock))
115                 return LRU_SKIP;
116
117         if (qd->qd_lockref.count == 0) {
118                 lockref_mark_dead(&qd->qd_lockref);
119                 list_move(&qd->qd_lru, dispose);
120         }
121
122         spin_unlock(&qd->qd_lockref.lock);
123         return LRU_REMOVED;
124 }
125
126 static unsigned long gfs2_qd_shrink_scan(struct shrinker *shrink,
127                                          struct shrink_control *sc)
128 {
129         LIST_HEAD(dispose);
130         unsigned long freed;
131
132         if (!(sc->gfp_mask & __GFP_FS))
133                 return SHRINK_STOP;
134
135         freed = list_lru_walk_node(&gfs2_qd_lru, sc->nid, gfs2_qd_isolate,
136                                    &dispose, &sc->nr_to_scan);
137
138         gfs2_qd_dispose(&dispose);
139
140         return freed;
141 }
142
143 static unsigned long gfs2_qd_shrink_count(struct shrinker *shrink,
144                                           struct shrink_control *sc)
145 {
146         return vfs_pressure_ratio(list_lru_count_node(&gfs2_qd_lru, sc->nid));
147 }
148
149 struct shrinker gfs2_qd_shrinker = {
150         .count_objects = gfs2_qd_shrink_count,
151         .scan_objects = gfs2_qd_shrink_scan,
152         .seeks = DEFAULT_SEEKS,
153         .flags = SHRINKER_NUMA_AWARE,
154 };
155
156
157 static u64 qd2index(struct gfs2_quota_data *qd)
158 {
159         struct kqid qid = qd->qd_id;
160         return (2 * (u64)from_kqid(&init_user_ns, qid)) +
161                 ((qid.type == USRQUOTA) ? 0 : 1);
162 }
163
164 static u64 qd2offset(struct gfs2_quota_data *qd)
165 {
166         u64 offset;
167
168         offset = qd2index(qd);
169         offset *= sizeof(struct gfs2_quota);
170
171         return offset;
172 }
173
174 static int qd_alloc(struct gfs2_sbd *sdp, struct kqid qid,
175                     struct gfs2_quota_data **qdp)
176 {
177         struct gfs2_quota_data *qd;
178         int error;
179
180         qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
181         if (!qd)
182                 return -ENOMEM;
183
184         qd->qd_lockref.count = 1;
185         spin_lock_init(&qd->qd_lockref.lock);
186         qd->qd_id = qid;
187         qd->qd_slot = -1;
188         INIT_LIST_HEAD(&qd->qd_lru);
189
190         error = gfs2_glock_get(sdp, qd2index(qd),
191                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
192         if (error)
193                 goto fail;
194
195         *qdp = qd;
196
197         return 0;
198
199 fail:
200         kmem_cache_free(gfs2_quotad_cachep, qd);
201         return error;
202 }
203
204 static int qd_get(struct gfs2_sbd *sdp, struct kqid qid,
205                   struct gfs2_quota_data **qdp)
206 {
207         struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
208         int error, found;
209
210         *qdp = NULL;
211
212         for (;;) {
213                 found = 0;
214                 spin_lock(&qd_lock);
215                 list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
216                         if (qid_eq(qd->qd_id, qid) &&
217                             lockref_get_not_dead(&qd->qd_lockref)) {
218                                 list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
219                                 found = 1;
220                                 break;
221                         }
222                 }
223
224                 if (!found)
225                         qd = NULL;
226
227                 if (!qd && new_qd) {
228                         qd = new_qd;
229                         list_add(&qd->qd_list, &sdp->sd_quota_list);
230                         atomic_inc(&sdp->sd_quota_count);
231                         new_qd = NULL;
232                 }
233
234                 spin_unlock(&qd_lock);
235
236                 if (qd) {
237                         if (new_qd) {
238                                 gfs2_glock_put(new_qd->qd_gl);
239                                 kmem_cache_free(gfs2_quotad_cachep, new_qd);
240                         }
241                         *qdp = qd;
242                         return 0;
243                 }
244
245                 error = qd_alloc(sdp, qid, &new_qd);
246                 if (error)
247                         return error;
248         }
249 }
250
251 static void qd_hold(struct gfs2_quota_data *qd)
252 {
253         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
254         gfs2_assert(sdp, !__lockref_is_dead(&qd->qd_lockref));
255         lockref_get(&qd->qd_lockref);
256 }
257
258 static void qd_put(struct gfs2_quota_data *qd)
259 {
260         if (lockref_put_or_lock(&qd->qd_lockref))
261                 return;
262
263         qd->qd_lockref.count = 0;
264         list_lru_add(&gfs2_qd_lru, &qd->qd_lru);
265         spin_unlock(&qd->qd_lockref.lock);
266
267 }
268
269 static int slot_get(struct gfs2_quota_data *qd)
270 {
271         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
272         unsigned int c, o = 0, b;
273         unsigned char byte = 0;
274
275         spin_lock(&qd_lock);
276
277         if (qd->qd_slot_count++) {
278                 spin_unlock(&qd_lock);
279                 return 0;
280         }
281
282         for (c = 0; c < sdp->sd_quota_chunks; c++)
283                 for (o = 0; o < PAGE_SIZE; o++) {
284                         byte = sdp->sd_quota_bitmap[c][o];
285                         if (byte != 0xFF)
286                                 goto found;
287                 }
288
289         goto fail;
290
291 found:
292         for (b = 0; b < 8; b++)
293                 if (!(byte & (1 << b)))
294                         break;
295         qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
296
297         if (qd->qd_slot >= sdp->sd_quota_slots)
298                 goto fail;
299
300         sdp->sd_quota_bitmap[c][o] |= 1 << b;
301
302         spin_unlock(&qd_lock);
303
304         return 0;
305
306 fail:
307         qd->qd_slot_count--;
308         spin_unlock(&qd_lock);
309         return -ENOSPC;
310 }
311
312 static void slot_hold(struct gfs2_quota_data *qd)
313 {
314         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
315
316         spin_lock(&qd_lock);
317         gfs2_assert(sdp, qd->qd_slot_count);
318         qd->qd_slot_count++;
319         spin_unlock(&qd_lock);
320 }
321
322 static void gfs2_icbit_munge(struct gfs2_sbd *sdp, unsigned char **bitmap,
323                              unsigned int bit, int new_value)
324 {
325         unsigned int c, o, b = bit;
326         int old_value;
327
328         c = b / (8 * PAGE_SIZE);
329         b %= 8 * PAGE_SIZE;
330         o = b / 8;
331         b %= 8;
332
333         old_value = (bitmap[c][o] & (1 << b));
334         gfs2_assert_withdraw(sdp, !old_value != !new_value);
335
336         if (new_value)
337                 bitmap[c][o] |= 1 << b;
338         else
339                 bitmap[c][o] &= ~(1 << b);
340 }
341
342 static void slot_put(struct gfs2_quota_data *qd)
343 {
344         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
345
346         spin_lock(&qd_lock);
347         gfs2_assert(sdp, qd->qd_slot_count);
348         if (!--qd->qd_slot_count) {
349                 gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
350                 qd->qd_slot = -1;
351         }
352         spin_unlock(&qd_lock);
353 }
354
355 static int bh_get(struct gfs2_quota_data *qd)
356 {
357         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
358         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
359         unsigned int block, offset;
360         struct buffer_head *bh;
361         int error;
362         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
363
364         mutex_lock(&sdp->sd_quota_mutex);
365
366         if (qd->qd_bh_count++) {
367                 mutex_unlock(&sdp->sd_quota_mutex);
368                 return 0;
369         }
370
371         block = qd->qd_slot / sdp->sd_qc_per_block;
372         offset = qd->qd_slot % sdp->sd_qc_per_block;
373
374         bh_map.b_size = 1 << ip->i_inode.i_blkbits;
375         error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
376         if (error)
377                 goto fail;
378         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
379         if (error)
380                 goto fail;
381         error = -EIO;
382         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
383                 goto fail_brelse;
384
385         qd->qd_bh = bh;
386         qd->qd_bh_qc = (struct gfs2_quota_change *)
387                 (bh->b_data + sizeof(struct gfs2_meta_header) +
388                  offset * sizeof(struct gfs2_quota_change));
389
390         mutex_unlock(&sdp->sd_quota_mutex);
391
392         return 0;
393
394 fail_brelse:
395         brelse(bh);
396 fail:
397         qd->qd_bh_count--;
398         mutex_unlock(&sdp->sd_quota_mutex);
399         return error;
400 }
401
402 static void bh_put(struct gfs2_quota_data *qd)
403 {
404         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
405
406         mutex_lock(&sdp->sd_quota_mutex);
407         gfs2_assert(sdp, qd->qd_bh_count);
408         if (!--qd->qd_bh_count) {
409                 brelse(qd->qd_bh);
410                 qd->qd_bh = NULL;
411                 qd->qd_bh_qc = NULL;
412         }
413         mutex_unlock(&sdp->sd_quota_mutex);
414 }
415
416 static int qd_check_sync(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd,
417                          u64 *sync_gen)
418 {
419         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
420             !test_bit(QDF_CHANGE, &qd->qd_flags) ||
421             (sync_gen && (qd->qd_sync_gen >= *sync_gen)))
422                 return 0;
423
424         if (!lockref_get_not_dead(&qd->qd_lockref))
425                 return 0;
426
427         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
428         set_bit(QDF_LOCKED, &qd->qd_flags);
429         qd->qd_change_sync = qd->qd_change;
430         gfs2_assert_warn(sdp, qd->qd_slot_count);
431         qd->qd_slot_count++;
432         return 1;
433 }
434
435 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
436 {
437         struct gfs2_quota_data *qd = NULL;
438         int error;
439         int found = 0;
440
441         *qdp = NULL;
442
443         if (sdp->sd_vfs->s_flags & MS_RDONLY)
444                 return 0;
445
446         spin_lock(&qd_lock);
447
448         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
449                 found = qd_check_sync(sdp, qd, &sdp->sd_quota_sync_gen);
450                 if (found)
451                         break;
452         }
453
454         if (!found)
455                 qd = NULL;
456
457         spin_unlock(&qd_lock);
458
459         if (qd) {
460                 gfs2_assert_warn(sdp, qd->qd_change_sync);
461                 error = bh_get(qd);
462                 if (error) {
463                         clear_bit(QDF_LOCKED, &qd->qd_flags);
464                         slot_put(qd);
465                         qd_put(qd);
466                         return error;
467                 }
468         }
469
470         *qdp = qd;
471
472         return 0;
473 }
474
475 static void qd_unlock(struct gfs2_quota_data *qd)
476 {
477         gfs2_assert_warn(qd->qd_gl->gl_sbd,
478                          test_bit(QDF_LOCKED, &qd->qd_flags));
479         clear_bit(QDF_LOCKED, &qd->qd_flags);
480         bh_put(qd);
481         slot_put(qd);
482         qd_put(qd);
483 }
484
485 static int qdsb_get(struct gfs2_sbd *sdp, struct kqid qid,
486                     struct gfs2_quota_data **qdp)
487 {
488         int error;
489
490         error = qd_get(sdp, qid, qdp);
491         if (error)
492                 return error;
493
494         error = slot_get(*qdp);
495         if (error)
496                 goto fail;
497
498         error = bh_get(*qdp);
499         if (error)
500                 goto fail_slot;
501
502         return 0;
503
504 fail_slot:
505         slot_put(*qdp);
506 fail:
507         qd_put(*qdp);
508         return error;
509 }
510
511 static void qdsb_put(struct gfs2_quota_data *qd)
512 {
513         bh_put(qd);
514         slot_put(qd);
515         qd_put(qd);
516 }
517
518 int gfs2_quota_hold(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
519 {
520         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
521         struct gfs2_quota_data **qd;
522         int error;
523
524         if (ip->i_res == NULL) {
525                 error = gfs2_rs_alloc(ip);
526                 if (error)
527                         return error;
528         }
529
530         qd = ip->i_res->rs_qa_qd;
531
532         if (gfs2_assert_warn(sdp, !ip->i_res->rs_qa_qd_num) ||
533             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
534                 return -EIO;
535
536         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
537                 return 0;
538
539         error = qdsb_get(sdp, make_kqid_uid(ip->i_inode.i_uid), qd);
540         if (error)
541                 goto out;
542         ip->i_res->rs_qa_qd_num++;
543         qd++;
544
545         error = qdsb_get(sdp, make_kqid_gid(ip->i_inode.i_gid), qd);
546         if (error)
547                 goto out;
548         ip->i_res->rs_qa_qd_num++;
549         qd++;
550
551         if (!uid_eq(uid, NO_UID_QUOTA_CHANGE) &&
552             !uid_eq(uid, ip->i_inode.i_uid)) {
553                 error = qdsb_get(sdp, make_kqid_uid(uid), qd);
554                 if (error)
555                         goto out;
556                 ip->i_res->rs_qa_qd_num++;
557                 qd++;
558         }
559
560         if (!gid_eq(gid, NO_GID_QUOTA_CHANGE) &&
561             !gid_eq(gid, ip->i_inode.i_gid)) {
562                 error = qdsb_get(sdp, make_kqid_gid(gid), qd);
563                 if (error)
564                         goto out;
565                 ip->i_res->rs_qa_qd_num++;
566                 qd++;
567         }
568
569 out:
570         if (error)
571                 gfs2_quota_unhold(ip);
572         return error;
573 }
574
575 void gfs2_quota_unhold(struct gfs2_inode *ip)
576 {
577         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
578         unsigned int x;
579
580         if (ip->i_res == NULL)
581                 return;
582         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
583
584         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
585                 qdsb_put(ip->i_res->rs_qa_qd[x]);
586                 ip->i_res->rs_qa_qd[x] = NULL;
587         }
588         ip->i_res->rs_qa_qd_num = 0;
589 }
590
591 static int sort_qd(const void *a, const void *b)
592 {
593         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
594         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
595
596         if (qid_lt(qd_a->qd_id, qd_b->qd_id))
597                 return -1;
598         if (qid_lt(qd_b->qd_id, qd_a->qd_id))
599                 return 1;
600         return 0;
601 }
602
603 static void do_qc(struct gfs2_quota_data *qd, s64 change)
604 {
605         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
606         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
607         struct gfs2_quota_change *qc = qd->qd_bh_qc;
608         s64 x;
609
610         mutex_lock(&sdp->sd_quota_mutex);
611         gfs2_trans_add_meta(ip->i_gl, qd->qd_bh);
612
613         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
614                 qc->qc_change = 0;
615                 qc->qc_flags = 0;
616                 if (qd->qd_id.type == USRQUOTA)
617                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
618                 qc->qc_id = cpu_to_be32(from_kqid(&init_user_ns, qd->qd_id));
619         }
620
621         x = be64_to_cpu(qc->qc_change) + change;
622         qc->qc_change = cpu_to_be64(x);
623
624         spin_lock(&qd_lock);
625         qd->qd_change = x;
626         spin_unlock(&qd_lock);
627
628         if (!x) {
629                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
630                 clear_bit(QDF_CHANGE, &qd->qd_flags);
631                 qc->qc_flags = 0;
632                 qc->qc_id = 0;
633                 slot_put(qd);
634                 qd_put(qd);
635         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
636                 qd_hold(qd);
637                 slot_hold(qd);
638         }
639
640         mutex_unlock(&sdp->sd_quota_mutex);
641 }
642
643 /**
644  * gfs2_adjust_quota - adjust record of current block usage
645  * @ip: The quota inode
646  * @loc: Offset of the entry in the quota file
647  * @change: The amount of usage change to record
648  * @qd: The quota data
649  * @fdq: The updated limits to record
650  *
651  * This function was mostly borrowed from gfs2_block_truncate_page which was
652  * in turn mostly borrowed from ext3
653  *
654  * Returns: 0 or -ve on error
655  */
656
657 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
658                              s64 change, struct gfs2_quota_data *qd,
659                              struct fs_disk_quota *fdq)
660 {
661         struct inode *inode = &ip->i_inode;
662         struct gfs2_sbd *sdp = GFS2_SB(inode);
663         struct address_space *mapping = inode->i_mapping;
664         unsigned long index = loc >> PAGE_CACHE_SHIFT;
665         unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
666         unsigned blocksize, iblock, pos;
667         struct buffer_head *bh;
668         struct page *page;
669         void *kaddr, *ptr;
670         struct gfs2_quota q;
671         int err, nbytes;
672         u64 size;
673
674         if (gfs2_is_stuffed(ip)) {
675                 err = gfs2_unstuff_dinode(ip, NULL);
676                 if (err)
677                         return err;
678         }
679
680         memset(&q, 0, sizeof(struct gfs2_quota));
681         err = gfs2_internal_read(ip, (char *)&q, &loc, sizeof(q));
682         if (err < 0)
683                 return err;
684
685         err = -EIO;
686         be64_add_cpu(&q.qu_value, change);
687         qd->qd_qb.qb_value = q.qu_value;
688         if (fdq) {
689                 if (fdq->d_fieldmask & FS_DQ_BSOFT) {
690                         q.qu_warn = cpu_to_be64(fdq->d_blk_softlimit >> sdp->sd_fsb2bb_shift);
691                         qd->qd_qb.qb_warn = q.qu_warn;
692                 }
693                 if (fdq->d_fieldmask & FS_DQ_BHARD) {
694                         q.qu_limit = cpu_to_be64(fdq->d_blk_hardlimit >> sdp->sd_fsb2bb_shift);
695                         qd->qd_qb.qb_limit = q.qu_limit;
696                 }
697                 if (fdq->d_fieldmask & FS_DQ_BCOUNT) {
698                         q.qu_value = cpu_to_be64(fdq->d_bcount >> sdp->sd_fsb2bb_shift);
699                         qd->qd_qb.qb_value = q.qu_value;
700                 }
701         }
702
703         /* Write the quota into the quota file on disk */
704         ptr = &q;
705         nbytes = sizeof(struct gfs2_quota);
706 get_a_page:
707         page = find_or_create_page(mapping, index, GFP_NOFS);
708         if (!page)
709                 return -ENOMEM;
710
711         blocksize = inode->i_sb->s_blocksize;
712         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
713
714         if (!page_has_buffers(page))
715                 create_empty_buffers(page, blocksize, 0);
716
717         bh = page_buffers(page);
718         pos = blocksize;
719         while (offset >= pos) {
720                 bh = bh->b_this_page;
721                 iblock++;
722                 pos += blocksize;
723         }
724
725         if (!buffer_mapped(bh)) {
726                 gfs2_block_map(inode, iblock, bh, 1);
727                 if (!buffer_mapped(bh))
728                         goto unlock_out;
729                 /* If it's a newly allocated disk block for quota, zero it */
730                 if (buffer_new(bh))
731                         zero_user(page, pos - blocksize, bh->b_size);
732         }
733
734         if (PageUptodate(page))
735                 set_buffer_uptodate(bh);
736
737         if (!buffer_uptodate(bh)) {
738                 ll_rw_block(READ | REQ_META, 1, &bh);
739                 wait_on_buffer(bh);
740                 if (!buffer_uptodate(bh))
741                         goto unlock_out;
742         }
743
744         gfs2_trans_add_data(ip->i_gl, bh);
745
746         kaddr = kmap_atomic(page);
747         if (offset + sizeof(struct gfs2_quota) > PAGE_CACHE_SIZE)
748                 nbytes = PAGE_CACHE_SIZE - offset;
749         memcpy(kaddr + offset, ptr, nbytes);
750         flush_dcache_page(page);
751         kunmap_atomic(kaddr);
752         unlock_page(page);
753         page_cache_release(page);
754
755         /* If quota straddles page boundary, we need to update the rest of the
756          * quota at the beginning of the next page */
757         if ((offset + sizeof(struct gfs2_quota)) > PAGE_CACHE_SIZE) {
758                 ptr = ptr + nbytes;
759                 nbytes = sizeof(struct gfs2_quota) - nbytes;
760                 offset = 0;
761                 index++;
762                 goto get_a_page;
763         }
764
765         size = loc + sizeof(struct gfs2_quota);
766         if (size > inode->i_size)
767                 i_size_write(inode, size);
768         inode->i_mtime = inode->i_atime = CURRENT_TIME;
769         mark_inode_dirty(inode);
770         return 0;
771
772 unlock_out:
773         unlock_page(page);
774         page_cache_release(page);
775         return err;
776 }
777
778 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
779 {
780         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
781         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
782         struct gfs2_alloc_parms ap = { .aflags = 0, };
783         unsigned int data_blocks, ind_blocks;
784         struct gfs2_holder *ghs, i_gh;
785         unsigned int qx, x;
786         struct gfs2_quota_data *qd;
787         unsigned reserved;
788         loff_t offset;
789         unsigned int nalloc = 0, blocks;
790         int error;
791
792         error = gfs2_rs_alloc(ip);
793         if (error)
794                 return error;
795
796         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
797                               &data_blocks, &ind_blocks);
798
799         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
800         if (!ghs)
801                 return -ENOMEM;
802
803         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
804         mutex_lock(&ip->i_inode.i_mutex);
805         for (qx = 0; qx < num_qd; qx++) {
806                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
807                                            GL_NOCACHE, &ghs[qx]);
808                 if (error)
809                         goto out;
810         }
811
812         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
813         if (error)
814                 goto out;
815
816         for (x = 0; x < num_qd; x++) {
817                 offset = qd2offset(qda[x]);
818                 if (gfs2_write_alloc_required(ip, offset,
819                                               sizeof(struct gfs2_quota)))
820                         nalloc++;
821         }
822
823         /* 
824          * 1 blk for unstuffing inode if stuffed. We add this extra
825          * block to the reservation unconditionally. If the inode
826          * doesn't need unstuffing, the block will be released to the 
827          * rgrp since it won't be allocated during the transaction
828          */
829         /* +3 in the end for unstuffing block, inode size update block
830          * and another block in case quota straddles page boundary and 
831          * two blocks need to be updated instead of 1 */
832         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
833
834         reserved = 1 + (nalloc * (data_blocks + ind_blocks));
835         ap.target = reserved;
836         error = gfs2_inplace_reserve(ip, &ap);
837         if (error)
838                 goto out_alloc;
839
840         if (nalloc)
841                 blocks += gfs2_rg_blocks(ip, reserved) + nalloc * ind_blocks + RES_STATFS;
842
843         error = gfs2_trans_begin(sdp, blocks, 0);
844         if (error)
845                 goto out_ipres;
846
847         for (x = 0; x < num_qd; x++) {
848                 qd = qda[x];
849                 offset = qd2offset(qd);
850                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
851                 if (error)
852                         goto out_end_trans;
853
854                 do_qc(qd, -qd->qd_change_sync);
855                 set_bit(QDF_REFRESH, &qd->qd_flags);
856         }
857
858         error = 0;
859
860 out_end_trans:
861         gfs2_trans_end(sdp);
862 out_ipres:
863         gfs2_inplace_release(ip);
864 out_alloc:
865         gfs2_glock_dq_uninit(&i_gh);
866 out:
867         while (qx--)
868                 gfs2_glock_dq_uninit(&ghs[qx]);
869         mutex_unlock(&ip->i_inode.i_mutex);
870         kfree(ghs);
871         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
872         return error;
873 }
874
875 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
876 {
877         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
878         struct gfs2_quota q;
879         struct gfs2_quota_lvb *qlvb;
880         loff_t pos;
881         int error;
882
883         memset(&q, 0, sizeof(struct gfs2_quota));
884         pos = qd2offset(qd);
885         error = gfs2_internal_read(ip, (char *)&q, &pos, sizeof(q));
886         if (error < 0)
887                 return error;
888
889         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
890         qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
891         qlvb->__pad = 0;
892         qlvb->qb_limit = q.qu_limit;
893         qlvb->qb_warn = q.qu_warn;
894         qlvb->qb_value = q.qu_value;
895         qd->qd_qb = *qlvb;
896
897         return 0;
898 }
899
900 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
901                     struct gfs2_holder *q_gh)
902 {
903         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
904         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
905         struct gfs2_holder i_gh;
906         int error;
907
908 restart:
909         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
910         if (error)
911                 return error;
912
913         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
914
915         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
916                 gfs2_glock_dq_uninit(q_gh);
917                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
918                                            GL_NOCACHE, q_gh);
919                 if (error)
920                         return error;
921
922                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
923                 if (error)
924                         goto fail;
925
926                 error = update_qd(sdp, qd);
927                 if (error)
928                         goto fail_gunlock;
929
930                 gfs2_glock_dq_uninit(&i_gh);
931                 gfs2_glock_dq_uninit(q_gh);
932                 force_refresh = 0;
933                 goto restart;
934         }
935
936         return 0;
937
938 fail_gunlock:
939         gfs2_glock_dq_uninit(&i_gh);
940 fail:
941         gfs2_glock_dq_uninit(q_gh);
942         return error;
943 }
944
945 int gfs2_quota_lock(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
946 {
947         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
948         struct gfs2_quota_data *qd;
949         unsigned int x;
950         int error = 0;
951
952         error = gfs2_quota_hold(ip, uid, gid);
953         if (error)
954                 return error;
955
956         if (capable(CAP_SYS_RESOURCE) ||
957             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
958                 return 0;
959
960         sort(ip->i_res->rs_qa_qd, ip->i_res->rs_qa_qd_num,
961              sizeof(struct gfs2_quota_data *), sort_qd, NULL);
962
963         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
964                 int force = NO_FORCE;
965                 qd = ip->i_res->rs_qa_qd[x];
966                 if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
967                         force = FORCE;
968                 error = do_glock(qd, force, &ip->i_res->rs_qa_qd_ghs[x]);
969                 if (error)
970                         break;
971         }
972
973         if (!error)
974                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
975         else {
976                 while (x--)
977                         gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
978                 gfs2_quota_unhold(ip);
979         }
980
981         return error;
982 }
983
984 static int need_sync(struct gfs2_quota_data *qd)
985 {
986         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
987         struct gfs2_tune *gt = &sdp->sd_tune;
988         s64 value;
989         unsigned int num, den;
990         int do_sync = 1;
991
992         if (!qd->qd_qb.qb_limit)
993                 return 0;
994
995         spin_lock(&qd_lock);
996         value = qd->qd_change;
997         spin_unlock(&qd_lock);
998
999         spin_lock(&gt->gt_spin);
1000         num = gt->gt_quota_scale_num;
1001         den = gt->gt_quota_scale_den;
1002         spin_unlock(&gt->gt_spin);
1003
1004         if (value < 0)
1005                 do_sync = 0;
1006         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
1007                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1008                 do_sync = 0;
1009         else {
1010                 value *= gfs2_jindex_size(sdp) * num;
1011                 value = div_s64(value, den);
1012                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
1013                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1014                         do_sync = 0;
1015         }
1016
1017         return do_sync;
1018 }
1019
1020 void gfs2_quota_unlock(struct gfs2_inode *ip)
1021 {
1022         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1023         struct gfs2_quota_data *qda[4];
1024         unsigned int count = 0;
1025         unsigned int x;
1026         int found;
1027
1028         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1029                 goto out;
1030
1031         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1032                 struct gfs2_quota_data *qd;
1033                 int sync;
1034
1035                 qd = ip->i_res->rs_qa_qd[x];
1036                 sync = need_sync(qd);
1037
1038                 gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
1039                 if (!sync)
1040                         continue;
1041
1042                 spin_lock(&qd_lock);
1043                 found = qd_check_sync(sdp, qd, NULL);
1044                 spin_unlock(&qd_lock);
1045
1046                 if (!found)
1047                         continue;
1048
1049                 gfs2_assert_warn(sdp, qd->qd_change_sync);
1050                 if (bh_get(qd)) {
1051                         clear_bit(QDF_LOCKED, &qd->qd_flags);
1052                         slot_put(qd);
1053                         qd_put(qd);
1054                         continue;
1055                 }
1056
1057                 qda[count++] = qd;
1058         }
1059
1060         if (count) {
1061                 do_sync(count, qda);
1062                 for (x = 0; x < count; x++)
1063                         qd_unlock(qda[x]);
1064         }
1065
1066 out:
1067         gfs2_quota_unhold(ip);
1068 }
1069
1070 #define MAX_LINE 256
1071
1072 static int print_message(struct gfs2_quota_data *qd, char *type)
1073 {
1074         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
1075
1076         printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\n",
1077                sdp->sd_fsname, type,
1078                (qd->qd_id.type == USRQUOTA) ? "user" : "group",
1079                from_kqid(&init_user_ns, qd->qd_id));
1080
1081         return 0;
1082 }
1083
1084 int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
1085 {
1086         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1087         struct gfs2_quota_data *qd;
1088         s64 value;
1089         unsigned int x;
1090         int error = 0;
1091
1092         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1093                 return 0;
1094
1095         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1096                 return 0;
1097
1098         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1099                 qd = ip->i_res->rs_qa_qd[x];
1100
1101                 if (!(qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1102                       qid_eq(qd->qd_id, make_kqid_gid(gid))))
1103                         continue;
1104
1105                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1106                 spin_lock(&qd_lock);
1107                 value += qd->qd_change;
1108                 spin_unlock(&qd_lock);
1109
1110                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
1111                         print_message(qd, "exceeded");
1112                         quota_send_warning(qd->qd_id,
1113                                            sdp->sd_vfs->s_dev, QUOTA_NL_BHARDWARN);
1114
1115                         error = -EDQUOT;
1116                         break;
1117                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
1118                            (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
1119                            time_after_eq(jiffies, qd->qd_last_warn +
1120                                          gfs2_tune_get(sdp,
1121                                                 gt_quota_warn_period) * HZ)) {
1122                         quota_send_warning(qd->qd_id,
1123                                            sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1124                         error = print_message(qd, "warning");
1125                         qd->qd_last_warn = jiffies;
1126                 }
1127         }
1128
1129         return error;
1130 }
1131
1132 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1133                        kuid_t uid, kgid_t gid)
1134 {
1135         struct gfs2_quota_data *qd;
1136         unsigned int x;
1137
1138         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1139                 return;
1140         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1141                 return;
1142
1143         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1144                 qd = ip->i_res->rs_qa_qd[x];
1145
1146                 if (qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1147                     qid_eq(qd->qd_id, make_kqid_gid(gid))) {
1148                         do_qc(qd, change);
1149                 }
1150         }
1151 }
1152
1153 int gfs2_quota_sync(struct super_block *sb, int type)
1154 {
1155         struct gfs2_sbd *sdp = sb->s_fs_info;
1156         struct gfs2_quota_data **qda;
1157         unsigned int max_qd = PAGE_SIZE/sizeof(struct gfs2_holder);
1158         unsigned int num_qd;
1159         unsigned int x;
1160         int error = 0;
1161
1162         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1163         if (!qda)
1164                 return -ENOMEM;
1165
1166         mutex_lock(&sdp->sd_quota_sync_mutex);
1167         sdp->sd_quota_sync_gen++;
1168
1169         do {
1170                 num_qd = 0;
1171
1172                 for (;;) {
1173                         error = qd_fish(sdp, qda + num_qd);
1174                         if (error || !qda[num_qd])
1175                                 break;
1176                         if (++num_qd == max_qd)
1177                                 break;
1178                 }
1179
1180                 if (num_qd) {
1181                         if (!error)
1182                                 error = do_sync(num_qd, qda);
1183                         if (!error)
1184                                 for (x = 0; x < num_qd; x++)
1185                                         qda[x]->qd_sync_gen =
1186                                                 sdp->sd_quota_sync_gen;
1187
1188                         for (x = 0; x < num_qd; x++)
1189                                 qd_unlock(qda[x]);
1190                 }
1191         } while (!error && num_qd == max_qd);
1192
1193         mutex_unlock(&sdp->sd_quota_sync_mutex);
1194         kfree(qda);
1195
1196         return error;
1197 }
1198
1199 int gfs2_quota_refresh(struct gfs2_sbd *sdp, struct kqid qid)
1200 {
1201         struct gfs2_quota_data *qd;
1202         struct gfs2_holder q_gh;
1203         int error;
1204
1205         error = qd_get(sdp, qid, &qd);
1206         if (error)
1207                 return error;
1208
1209         error = do_glock(qd, FORCE, &q_gh);
1210         if (!error)
1211                 gfs2_glock_dq_uninit(&q_gh);
1212
1213         qd_put(qd);
1214         return error;
1215 }
1216
1217 static void gfs2_quota_change_in(struct gfs2_quota_change_host *qc, const void *buf)
1218 {
1219         const struct gfs2_quota_change *str = buf;
1220
1221         qc->qc_change = be64_to_cpu(str->qc_change);
1222         qc->qc_flags = be32_to_cpu(str->qc_flags);
1223         qc->qc_id = make_kqid(&init_user_ns,
1224                               (qc->qc_flags & GFS2_QCF_USER)?USRQUOTA:GRPQUOTA,
1225                               be32_to_cpu(str->qc_id));
1226 }
1227
1228 int gfs2_quota_init(struct gfs2_sbd *sdp)
1229 {
1230         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1231         u64 size = i_size_read(sdp->sd_qc_inode);
1232         unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1233         unsigned int x, slot = 0;
1234         unsigned int found = 0;
1235         u64 dblock;
1236         u32 extlen = 0;
1237         int error;
1238
1239         if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1240                 return -EIO;
1241
1242         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1243         sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1244
1245         error = -ENOMEM;
1246
1247         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1248                                        sizeof(unsigned char *), GFP_NOFS);
1249         if (!sdp->sd_quota_bitmap)
1250                 return error;
1251
1252         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1253                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_NOFS);
1254                 if (!sdp->sd_quota_bitmap[x])
1255                         goto fail;
1256         }
1257
1258         for (x = 0; x < blocks; x++) {
1259                 struct buffer_head *bh;
1260                 unsigned int y;
1261
1262                 if (!extlen) {
1263                         int new = 0;
1264                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1265                         if (error)
1266                                 goto fail;
1267                 }
1268                 error = -EIO;
1269                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1270                 if (!bh)
1271                         goto fail;
1272                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1273                         brelse(bh);
1274                         goto fail;
1275                 }
1276
1277                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1278                      y++, slot++) {
1279                         struct gfs2_quota_change_host qc;
1280                         struct gfs2_quota_data *qd;
1281
1282                         gfs2_quota_change_in(&qc, bh->b_data +
1283                                           sizeof(struct gfs2_meta_header) +
1284                                           y * sizeof(struct gfs2_quota_change));
1285                         if (!qc.qc_change)
1286                                 continue;
1287
1288                         error = qd_alloc(sdp, qc.qc_id, &qd);
1289                         if (error) {
1290                                 brelse(bh);
1291                                 goto fail;
1292                         }
1293
1294                         set_bit(QDF_CHANGE, &qd->qd_flags);
1295                         qd->qd_change = qc.qc_change;
1296                         qd->qd_slot = slot;
1297                         qd->qd_slot_count = 1;
1298
1299                         spin_lock(&qd_lock);
1300                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1301                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1302                         atomic_inc(&sdp->sd_quota_count);
1303                         spin_unlock(&qd_lock);
1304
1305                         found++;
1306                 }
1307
1308                 brelse(bh);
1309                 dblock++;
1310                 extlen--;
1311         }
1312
1313         if (found)
1314                 fs_info(sdp, "found %u quota changes\n", found);
1315
1316         return 0;
1317
1318 fail:
1319         gfs2_quota_cleanup(sdp);
1320         return error;
1321 }
1322
1323 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1324 {
1325         struct list_head *head = &sdp->sd_quota_list;
1326         struct gfs2_quota_data *qd;
1327         unsigned int x;
1328
1329         spin_lock(&qd_lock);
1330         while (!list_empty(head)) {
1331                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1332
1333                 /*
1334                  * To be removed in due course... we should be able to
1335                  * ensure that all refs to the qd have done by this point
1336                  * so that this rather odd test is not required
1337                  */
1338                 spin_lock(&qd->qd_lockref.lock);
1339                 if (qd->qd_lockref.count > 1 ||
1340                     (qd->qd_lockref.count && !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1341                         spin_unlock(&qd->qd_lockref.lock);
1342                         list_move(&qd->qd_list, head);
1343                         spin_unlock(&qd_lock);
1344                         schedule();
1345                         spin_lock(&qd_lock);
1346                         continue;
1347                 }
1348                 spin_unlock(&qd->qd_lockref.lock);
1349
1350                 list_del(&qd->qd_list);
1351                 /* Also remove if this qd exists in the reclaim list */
1352                 list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
1353                 atomic_dec(&sdp->sd_quota_count);
1354                 spin_unlock(&qd_lock);
1355
1356                 if (!qd->qd_lockref.count) {
1357                         gfs2_assert_warn(sdp, !qd->qd_change);
1358                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1359                 } else
1360                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1361                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1362
1363                 gfs2_glock_put(qd->qd_gl);
1364                 kmem_cache_free(gfs2_quotad_cachep, qd);
1365
1366                 spin_lock(&qd_lock);
1367         }
1368         spin_unlock(&qd_lock);
1369
1370         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1371
1372         if (sdp->sd_quota_bitmap) {
1373                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1374                         kfree(sdp->sd_quota_bitmap[x]);
1375                 kfree(sdp->sd_quota_bitmap);
1376         }
1377 }
1378
1379 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1380 {
1381         if (error == 0 || error == -EROFS)
1382                 return;
1383         if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1384                 fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1385 }
1386
1387 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1388                                int (*fxn)(struct super_block *sb, int type),
1389                                unsigned long t, unsigned long *timeo,
1390                                unsigned int *new_timeo)
1391 {
1392         if (t >= *timeo) {
1393                 int error = fxn(sdp->sd_vfs, 0);
1394                 quotad_error(sdp, msg, error);
1395                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1396         } else {
1397                 *timeo -= t;
1398         }
1399 }
1400
1401 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1402 {
1403         struct gfs2_inode *ip;
1404
1405         while(1) {
1406                 ip = NULL;
1407                 spin_lock(&sdp->sd_trunc_lock);
1408                 if (!list_empty(&sdp->sd_trunc_list)) {
1409                         ip = list_entry(sdp->sd_trunc_list.next,
1410                                         struct gfs2_inode, i_trunc_list);
1411                         list_del_init(&ip->i_trunc_list);
1412                 }
1413                 spin_unlock(&sdp->sd_trunc_lock);
1414                 if (ip == NULL)
1415                         return;
1416                 gfs2_glock_finish_truncate(ip);
1417         }
1418 }
1419
1420 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1421         if (!sdp->sd_statfs_force_sync) {
1422                 sdp->sd_statfs_force_sync = 1;
1423                 wake_up(&sdp->sd_quota_wait);
1424         }
1425 }
1426
1427
1428 /**
1429  * gfs2_quotad - Write cached quota changes into the quota file
1430  * @sdp: Pointer to GFS2 superblock
1431  *
1432  */
1433
1434 int gfs2_quotad(void *data)
1435 {
1436         struct gfs2_sbd *sdp = data;
1437         struct gfs2_tune *tune = &sdp->sd_tune;
1438         unsigned long statfs_timeo = 0;
1439         unsigned long quotad_timeo = 0;
1440         unsigned long t = 0;
1441         DEFINE_WAIT(wait);
1442         int empty;
1443
1444         while (!kthread_should_stop()) {
1445
1446                 /* Update the master statfs file */
1447                 if (sdp->sd_statfs_force_sync) {
1448                         int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1449                         quotad_error(sdp, "statfs", error);
1450                         statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1451                 }
1452                 else
1453                         quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1454                                            &statfs_timeo,
1455                                            &tune->gt_statfs_quantum);
1456
1457                 /* Update quota file */
1458                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
1459                                    &quotad_timeo, &tune->gt_quota_quantum);
1460
1461                 /* Check for & recover partially truncated inodes */
1462                 quotad_check_trunc_list(sdp);
1463
1464                 try_to_freeze();
1465
1466                 t = min(quotad_timeo, statfs_timeo);
1467
1468                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1469                 spin_lock(&sdp->sd_trunc_lock);
1470                 empty = list_empty(&sdp->sd_trunc_list);
1471                 spin_unlock(&sdp->sd_trunc_lock);
1472                 if (empty && !sdp->sd_statfs_force_sync)
1473                         t -= schedule_timeout(t);
1474                 else
1475                         t = 0;
1476                 finish_wait(&sdp->sd_quota_wait, &wait);
1477         }
1478
1479         return 0;
1480 }
1481
1482 static int gfs2_quota_get_xstate(struct super_block *sb,
1483                                  struct fs_quota_stat *fqs)
1484 {
1485         struct gfs2_sbd *sdp = sb->s_fs_info;
1486
1487         memset(fqs, 0, sizeof(struct fs_quota_stat));
1488         fqs->qs_version = FS_QSTAT_VERSION;
1489
1490         switch (sdp->sd_args.ar_quota) {
1491         case GFS2_QUOTA_ON:
1492                 fqs->qs_flags |= (FS_QUOTA_UDQ_ENFD | FS_QUOTA_GDQ_ENFD);
1493                 /*FALLTHRU*/
1494         case GFS2_QUOTA_ACCOUNT:
1495                 fqs->qs_flags |= (FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT);
1496                 break;
1497         case GFS2_QUOTA_OFF:
1498                 break;
1499         }
1500
1501         if (sdp->sd_quota_inode) {
1502                 fqs->qs_uquota.qfs_ino = GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1503                 fqs->qs_uquota.qfs_nblks = sdp->sd_quota_inode->i_blocks;
1504         }
1505         fqs->qs_uquota.qfs_nextents = 1; /* unsupported */
1506         fqs->qs_gquota = fqs->qs_uquota; /* its the same inode in both cases */
1507         fqs->qs_incoredqs = list_lru_count(&gfs2_qd_lru);
1508         return 0;
1509 }
1510
1511 static int gfs2_get_dqblk(struct super_block *sb, struct kqid qid,
1512                           struct fs_disk_quota *fdq)
1513 {
1514         struct gfs2_sbd *sdp = sb->s_fs_info;
1515         struct gfs2_quota_lvb *qlvb;
1516         struct gfs2_quota_data *qd;
1517         struct gfs2_holder q_gh;
1518         int error;
1519
1520         memset(fdq, 0, sizeof(struct fs_disk_quota));
1521
1522         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1523                 return -ESRCH; /* Crazy XFS error code */
1524
1525         if ((qid.type != USRQUOTA) &&
1526             (qid.type != GRPQUOTA))
1527                 return -EINVAL;
1528
1529         error = qd_get(sdp, qid, &qd);
1530         if (error)
1531                 return error;
1532         error = do_glock(qd, FORCE, &q_gh);
1533         if (error)
1534                 goto out;
1535
1536         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1537         fdq->d_version = FS_DQUOT_VERSION;
1538         fdq->d_flags = (qid.type == USRQUOTA) ? FS_USER_QUOTA : FS_GROUP_QUOTA;
1539         fdq->d_id = from_kqid_munged(current_user_ns(), qid);
1540         fdq->d_blk_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_fsb2bb_shift;
1541         fdq->d_blk_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_fsb2bb_shift;
1542         fdq->d_bcount = be64_to_cpu(qlvb->qb_value) << sdp->sd_fsb2bb_shift;
1543
1544         gfs2_glock_dq_uninit(&q_gh);
1545 out:
1546         qd_put(qd);
1547         return error;
1548 }
1549
1550 /* GFS2 only supports a subset of the XFS fields */
1551 #define GFS2_FIELDMASK (FS_DQ_BSOFT|FS_DQ_BHARD|FS_DQ_BCOUNT)
1552
1553 static int gfs2_set_dqblk(struct super_block *sb, struct kqid qid,
1554                           struct fs_disk_quota *fdq)
1555 {
1556         struct gfs2_sbd *sdp = sb->s_fs_info;
1557         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1558         struct gfs2_quota_data *qd;
1559         struct gfs2_holder q_gh, i_gh;
1560         unsigned int data_blocks, ind_blocks;
1561         unsigned int blocks = 0;
1562         int alloc_required;
1563         loff_t offset;
1564         int error;
1565
1566         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1567                 return -ESRCH; /* Crazy XFS error code */
1568
1569         if ((qid.type != USRQUOTA) &&
1570             (qid.type != GRPQUOTA))
1571                 return -EINVAL;
1572
1573         if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1574                 return -EINVAL;
1575
1576         error = qd_get(sdp, qid, &qd);
1577         if (error)
1578                 return error;
1579
1580         error = gfs2_rs_alloc(ip);
1581         if (error)
1582                 goto out_put;
1583
1584         mutex_lock(&ip->i_inode.i_mutex);
1585         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1586         if (error)
1587                 goto out_unlockput;
1588         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1589         if (error)
1590                 goto out_q;
1591
1592         /* Check for existing entry, if none then alloc new blocks */
1593         error = update_qd(sdp, qd);
1594         if (error)
1595                 goto out_i;
1596
1597         /* If nothing has changed, this is a no-op */
1598         if ((fdq->d_fieldmask & FS_DQ_BSOFT) &&
1599             ((fdq->d_blk_softlimit >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1600                 fdq->d_fieldmask ^= FS_DQ_BSOFT;
1601
1602         if ((fdq->d_fieldmask & FS_DQ_BHARD) &&
1603             ((fdq->d_blk_hardlimit >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1604                 fdq->d_fieldmask ^= FS_DQ_BHARD;
1605
1606         if ((fdq->d_fieldmask & FS_DQ_BCOUNT) &&
1607             ((fdq->d_bcount >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1608                 fdq->d_fieldmask ^= FS_DQ_BCOUNT;
1609
1610         if (fdq->d_fieldmask == 0)
1611                 goto out_i;
1612
1613         offset = qd2offset(qd);
1614         alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1615         if (gfs2_is_stuffed(ip))
1616                 alloc_required = 1;
1617         if (alloc_required) {
1618                 struct gfs2_alloc_parms ap = { .aflags = 0, };
1619                 gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1620                                        &data_blocks, &ind_blocks);
1621                 blocks = 1 + data_blocks + ind_blocks;
1622                 ap.target = blocks;
1623                 error = gfs2_inplace_reserve(ip, &ap);
1624                 if (error)
1625                         goto out_i;
1626                 blocks += gfs2_rg_blocks(ip, blocks);
1627         }
1628
1629         /* Some quotas span block boundaries and can update two blocks,
1630            adding an extra block to the transaction to handle such quotas */
1631         error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1632         if (error)
1633                 goto out_release;
1634
1635         /* Apply changes */
1636         error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1637
1638         gfs2_trans_end(sdp);
1639 out_release:
1640         if (alloc_required)
1641                 gfs2_inplace_release(ip);
1642 out_i:
1643         gfs2_glock_dq_uninit(&i_gh);
1644 out_q:
1645         gfs2_glock_dq_uninit(&q_gh);
1646 out_unlockput:
1647         mutex_unlock(&ip->i_inode.i_mutex);
1648 out_put:
1649         qd_put(qd);
1650         return error;
1651 }
1652
1653 const struct quotactl_ops gfs2_quotactl_ops = {
1654         .quota_sync     = gfs2_quota_sync,
1655         .get_xstate     = gfs2_quota_get_xstate,
1656         .get_dqblk      = gfs2_get_dqblk,
1657         .set_dqblk      = gfs2_set_dqblk,
1658 };