Merge branches 'pm-cpufreq', 'pm-cpuidle', 'pm-devfreq', 'pm-opp' and 'pm-tools'
[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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
40
41 #include <linux/sched.h>
42 #include <linux/slab.h>
43 #include <linux/mm.h>
44 #include <linux/spinlock.h>
45 #include <linux/completion.h>
46 #include <linux/buffer_head.h>
47 #include <linux/sort.h>
48 #include <linux/fs.h>
49 #include <linux/bio.h>
50 #include <linux/gfs2_ondisk.h>
51 #include <linux/kthread.h>
52 #include <linux/freezer.h>
53 #include <linux/quota.h>
54 #include <linux/dqblk_xfs.h>
55 #include <linux/lockref.h>
56 #include <linux/list_lru.h>
57 #include <linux/rcupdate.h>
58 #include <linux/rculist_bl.h>
59 #include <linux/bit_spinlock.h>
60 #include <linux/jhash.h>
61 #include <linux/vmalloc.h>
62
63 #include "gfs2.h"
64 #include "incore.h"
65 #include "bmap.h"
66 #include "glock.h"
67 #include "glops.h"
68 #include "log.h"
69 #include "meta_io.h"
70 #include "quota.h"
71 #include "rgrp.h"
72 #include "super.h"
73 #include "trans.h"
74 #include "inode.h"
75 #include "util.h"
76
77 #define GFS2_QD_HASH_SHIFT      12
78 #define GFS2_QD_HASH_SIZE       (1 << GFS2_QD_HASH_SHIFT)
79 #define GFS2_QD_HASH_MASK       (GFS2_QD_HASH_SIZE - 1)
80
81 /* Lock order: qd_lock -> bucket lock -> qd->lockref.lock -> lru lock */
82 /*                     -> sd_bitmap_lock                              */
83 static DEFINE_SPINLOCK(qd_lock);
84 struct list_lru gfs2_qd_lru;
85
86 static struct hlist_bl_head qd_hash_table[GFS2_QD_HASH_SIZE];
87
88 static unsigned int gfs2_qd_hash(const struct gfs2_sbd *sdp,
89                                  const struct kqid qid)
90 {
91         unsigned int h;
92
93         h = jhash(&sdp, sizeof(struct gfs2_sbd *), 0);
94         h = jhash(&qid, sizeof(struct kqid), h);
95
96         return h & GFS2_QD_HASH_MASK;
97 }
98
99 static inline void spin_lock_bucket(unsigned int hash)
100 {
101         hlist_bl_lock(&qd_hash_table[hash]);
102 }
103
104 static inline void spin_unlock_bucket(unsigned int hash)
105 {
106         hlist_bl_unlock(&qd_hash_table[hash]);
107 }
108
109 static void gfs2_qd_dealloc(struct rcu_head *rcu)
110 {
111         struct gfs2_quota_data *qd = container_of(rcu, struct gfs2_quota_data, qd_rcu);
112         kmem_cache_free(gfs2_quotad_cachep, qd);
113 }
114
115 static void gfs2_qd_dispose(struct list_head *list)
116 {
117         struct gfs2_quota_data *qd;
118         struct gfs2_sbd *sdp;
119
120         while (!list_empty(list)) {
121                 qd = list_entry(list->next, struct gfs2_quota_data, qd_lru);
122                 sdp = qd->qd_gl->gl_sbd;
123
124                 list_del(&qd->qd_lru);
125
126                 /* Free from the filesystem-specific list */
127                 spin_lock(&qd_lock);
128                 list_del(&qd->qd_list);
129                 spin_unlock(&qd_lock);
130
131                 spin_lock_bucket(qd->qd_hash);
132                 hlist_bl_del_rcu(&qd->qd_hlist);
133                 spin_unlock_bucket(qd->qd_hash);
134
135                 gfs2_assert_warn(sdp, !qd->qd_change);
136                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
137                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
138
139                 gfs2_glock_put(qd->qd_gl);
140                 atomic_dec(&sdp->sd_quota_count);
141
142                 /* Delete it from the common reclaim list */
143                 call_rcu(&qd->qd_rcu, gfs2_qd_dealloc);
144         }
145 }
146
147
148 static enum lru_status gfs2_qd_isolate(struct list_head *item, spinlock_t *lock, void *arg)
149 {
150         struct list_head *dispose = arg;
151         struct gfs2_quota_data *qd = list_entry(item, struct gfs2_quota_data, qd_lru);
152
153         if (!spin_trylock(&qd->qd_lockref.lock))
154                 return LRU_SKIP;
155
156         if (qd->qd_lockref.count == 0) {
157                 lockref_mark_dead(&qd->qd_lockref);
158                 list_move(&qd->qd_lru, dispose);
159         }
160
161         spin_unlock(&qd->qd_lockref.lock);
162         return LRU_REMOVED;
163 }
164
165 static unsigned long gfs2_qd_shrink_scan(struct shrinker *shrink,
166                                          struct shrink_control *sc)
167 {
168         LIST_HEAD(dispose);
169         unsigned long freed;
170
171         if (!(sc->gfp_mask & __GFP_FS))
172                 return SHRINK_STOP;
173
174         freed = list_lru_walk_node(&gfs2_qd_lru, sc->nid, gfs2_qd_isolate,
175                                    &dispose, &sc->nr_to_scan);
176
177         gfs2_qd_dispose(&dispose);
178
179         return freed;
180 }
181
182 static unsigned long gfs2_qd_shrink_count(struct shrinker *shrink,
183                                           struct shrink_control *sc)
184 {
185         return vfs_pressure_ratio(list_lru_count_node(&gfs2_qd_lru, sc->nid));
186 }
187
188 struct shrinker gfs2_qd_shrinker = {
189         .count_objects = gfs2_qd_shrink_count,
190         .scan_objects = gfs2_qd_shrink_scan,
191         .seeks = DEFAULT_SEEKS,
192         .flags = SHRINKER_NUMA_AWARE,
193 };
194
195
196 static u64 qd2index(struct gfs2_quota_data *qd)
197 {
198         struct kqid qid = qd->qd_id;
199         return (2 * (u64)from_kqid(&init_user_ns, qid)) +
200                 ((qid.type == USRQUOTA) ? 0 : 1);
201 }
202
203 static u64 qd2offset(struct gfs2_quota_data *qd)
204 {
205         u64 offset;
206
207         offset = qd2index(qd);
208         offset *= sizeof(struct gfs2_quota);
209
210         return offset;
211 }
212
213 static struct gfs2_quota_data *qd_alloc(unsigned hash, struct gfs2_sbd *sdp, struct kqid qid)
214 {
215         struct gfs2_quota_data *qd;
216         int error;
217
218         qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
219         if (!qd)
220                 return NULL;
221
222         qd->qd_sbd = sdp;
223         qd->qd_lockref.count = 1;
224         spin_lock_init(&qd->qd_lockref.lock);
225         qd->qd_id = qid;
226         qd->qd_slot = -1;
227         INIT_LIST_HEAD(&qd->qd_lru);
228         qd->qd_hash = hash;
229
230         error = gfs2_glock_get(sdp, qd2index(qd),
231                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
232         if (error)
233                 goto fail;
234
235         return qd;
236
237 fail:
238         kmem_cache_free(gfs2_quotad_cachep, qd);
239         return NULL;
240 }
241
242 static struct gfs2_quota_data *gfs2_qd_search_bucket(unsigned int hash,
243                                                      const struct gfs2_sbd *sdp,
244                                                      struct kqid qid)
245 {
246         struct gfs2_quota_data *qd;
247         struct hlist_bl_node *h;
248
249         hlist_bl_for_each_entry_rcu(qd, h, &qd_hash_table[hash], qd_hlist) {
250                 if (!qid_eq(qd->qd_id, qid))
251                         continue;
252                 if (qd->qd_sbd != sdp)
253                         continue;
254                 if (lockref_get_not_dead(&qd->qd_lockref)) {
255                         list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
256                         return qd;
257                 }
258         }
259
260         return NULL;
261 }
262
263
264 static int qd_get(struct gfs2_sbd *sdp, struct kqid qid,
265                   struct gfs2_quota_data **qdp)
266 {
267         struct gfs2_quota_data *qd, *new_qd;
268         unsigned int hash = gfs2_qd_hash(sdp, qid);
269
270         rcu_read_lock();
271         *qdp = qd = gfs2_qd_search_bucket(hash, sdp, qid);
272         rcu_read_unlock();
273
274         if (qd)
275                 return 0;
276
277         new_qd = qd_alloc(hash, sdp, qid);
278         if (!new_qd)
279                 return -ENOMEM;
280
281         spin_lock(&qd_lock);
282         spin_lock_bucket(hash);
283         *qdp = qd = gfs2_qd_search_bucket(hash, sdp, qid);
284         if (qd == NULL) {
285                 *qdp = new_qd;
286                 list_add(&new_qd->qd_list, &sdp->sd_quota_list);
287                 hlist_bl_add_head_rcu(&new_qd->qd_hlist, &qd_hash_table[hash]);
288                 atomic_inc(&sdp->sd_quota_count);
289         }
290         spin_unlock_bucket(hash);
291         spin_unlock(&qd_lock);
292
293         if (qd) {
294                 gfs2_glock_put(new_qd->qd_gl);
295                 kmem_cache_free(gfs2_quotad_cachep, new_qd);
296         }
297
298         return 0;
299 }
300
301
302 static void qd_hold(struct gfs2_quota_data *qd)
303 {
304         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
305         gfs2_assert(sdp, !__lockref_is_dead(&qd->qd_lockref));
306         lockref_get(&qd->qd_lockref);
307 }
308
309 static void qd_put(struct gfs2_quota_data *qd)
310 {
311         if (lockref_put_or_lock(&qd->qd_lockref))
312                 return;
313
314         qd->qd_lockref.count = 0;
315         list_lru_add(&gfs2_qd_lru, &qd->qd_lru);
316         spin_unlock(&qd->qd_lockref.lock);
317
318 }
319
320 static int slot_get(struct gfs2_quota_data *qd)
321 {
322         struct gfs2_sbd *sdp = qd->qd_sbd;
323         unsigned int bit;
324         int error = 0;
325
326         spin_lock(&sdp->sd_bitmap_lock);
327         if (qd->qd_slot_count != 0)
328                 goto out;
329
330         error = -ENOSPC;
331         bit = find_first_zero_bit(sdp->sd_quota_bitmap, sdp->sd_quota_slots);
332         if (bit < sdp->sd_quota_slots) {
333                 set_bit(bit, sdp->sd_quota_bitmap);
334                 qd->qd_slot = bit;
335                 error = 0;
336 out:
337                 qd->qd_slot_count++;
338         }
339         spin_unlock(&sdp->sd_bitmap_lock);
340
341         return error;
342 }
343
344 static void slot_hold(struct gfs2_quota_data *qd)
345 {
346         struct gfs2_sbd *sdp = qd->qd_sbd;
347
348         spin_lock(&sdp->sd_bitmap_lock);
349         gfs2_assert(sdp, qd->qd_slot_count);
350         qd->qd_slot_count++;
351         spin_unlock(&sdp->sd_bitmap_lock);
352 }
353
354 static void slot_put(struct gfs2_quota_data *qd)
355 {
356         struct gfs2_sbd *sdp = qd->qd_sbd;
357
358         spin_lock(&sdp->sd_bitmap_lock);
359         gfs2_assert(sdp, qd->qd_slot_count);
360         if (!--qd->qd_slot_count) {
361                 BUG_ON(!test_and_clear_bit(qd->qd_slot, sdp->sd_quota_bitmap));
362                 qd->qd_slot = -1;
363         }
364         spin_unlock(&sdp->sd_bitmap_lock);
365 }
366
367 static int bh_get(struct gfs2_quota_data *qd)
368 {
369         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
370         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
371         unsigned int block, offset;
372         struct buffer_head *bh;
373         int error;
374         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
375
376         mutex_lock(&sdp->sd_quota_mutex);
377
378         if (qd->qd_bh_count++) {
379                 mutex_unlock(&sdp->sd_quota_mutex);
380                 return 0;
381         }
382
383         block = qd->qd_slot / sdp->sd_qc_per_block;
384         offset = qd->qd_slot % sdp->sd_qc_per_block;
385
386         bh_map.b_size = 1 << ip->i_inode.i_blkbits;
387         error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
388         if (error)
389                 goto fail;
390         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
391         if (error)
392                 goto fail;
393         error = -EIO;
394         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
395                 goto fail_brelse;
396
397         qd->qd_bh = bh;
398         qd->qd_bh_qc = (struct gfs2_quota_change *)
399                 (bh->b_data + sizeof(struct gfs2_meta_header) +
400                  offset * sizeof(struct gfs2_quota_change));
401
402         mutex_unlock(&sdp->sd_quota_mutex);
403
404         return 0;
405
406 fail_brelse:
407         brelse(bh);
408 fail:
409         qd->qd_bh_count--;
410         mutex_unlock(&sdp->sd_quota_mutex);
411         return error;
412 }
413
414 static void bh_put(struct gfs2_quota_data *qd)
415 {
416         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
417
418         mutex_lock(&sdp->sd_quota_mutex);
419         gfs2_assert(sdp, qd->qd_bh_count);
420         if (!--qd->qd_bh_count) {
421                 brelse(qd->qd_bh);
422                 qd->qd_bh = NULL;
423                 qd->qd_bh_qc = NULL;
424         }
425         mutex_unlock(&sdp->sd_quota_mutex);
426 }
427
428 static int qd_check_sync(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd,
429                          u64 *sync_gen)
430 {
431         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
432             !test_bit(QDF_CHANGE, &qd->qd_flags) ||
433             (sync_gen && (qd->qd_sync_gen >= *sync_gen)))
434                 return 0;
435
436         if (!lockref_get_not_dead(&qd->qd_lockref))
437                 return 0;
438
439         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
440         set_bit(QDF_LOCKED, &qd->qd_flags);
441         qd->qd_change_sync = qd->qd_change;
442         slot_hold(qd);
443         return 1;
444 }
445
446 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
447 {
448         struct gfs2_quota_data *qd = NULL;
449         int error;
450         int found = 0;
451
452         *qdp = NULL;
453
454         if (sdp->sd_vfs->s_flags & MS_RDONLY)
455                 return 0;
456
457         spin_lock(&qd_lock);
458
459         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
460                 found = qd_check_sync(sdp, qd, &sdp->sd_quota_sync_gen);
461                 if (found)
462                         break;
463         }
464
465         if (!found)
466                 qd = NULL;
467
468         spin_unlock(&qd_lock);
469
470         if (qd) {
471                 gfs2_assert_warn(sdp, qd->qd_change_sync);
472                 error = bh_get(qd);
473                 if (error) {
474                         clear_bit(QDF_LOCKED, &qd->qd_flags);
475                         slot_put(qd);
476                         qd_put(qd);
477                         return error;
478                 }
479         }
480
481         *qdp = qd;
482
483         return 0;
484 }
485
486 static void qd_unlock(struct gfs2_quota_data *qd)
487 {
488         gfs2_assert_warn(qd->qd_gl->gl_sbd,
489                          test_bit(QDF_LOCKED, &qd->qd_flags));
490         clear_bit(QDF_LOCKED, &qd->qd_flags);
491         bh_put(qd);
492         slot_put(qd);
493         qd_put(qd);
494 }
495
496 static int qdsb_get(struct gfs2_sbd *sdp, struct kqid qid,
497                     struct gfs2_quota_data **qdp)
498 {
499         int error;
500
501         error = qd_get(sdp, qid, qdp);
502         if (error)
503                 return error;
504
505         error = slot_get(*qdp);
506         if (error)
507                 goto fail;
508
509         error = bh_get(*qdp);
510         if (error)
511                 goto fail_slot;
512
513         return 0;
514
515 fail_slot:
516         slot_put(*qdp);
517 fail:
518         qd_put(*qdp);
519         return error;
520 }
521
522 static void qdsb_put(struct gfs2_quota_data *qd)
523 {
524         bh_put(qd);
525         slot_put(qd);
526         qd_put(qd);
527 }
528
529 int gfs2_quota_hold(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
530 {
531         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
532         struct gfs2_quota_data **qd;
533         int error;
534
535         if (ip->i_res == NULL) {
536                 error = gfs2_rs_alloc(ip);
537                 if (error)
538                         return error;
539         }
540
541         qd = ip->i_res->rs_qa_qd;
542
543         if (gfs2_assert_warn(sdp, !ip->i_res->rs_qa_qd_num) ||
544             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
545                 return -EIO;
546
547         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
548                 return 0;
549
550         error = qdsb_get(sdp, make_kqid_uid(ip->i_inode.i_uid), qd);
551         if (error)
552                 goto out;
553         ip->i_res->rs_qa_qd_num++;
554         qd++;
555
556         error = qdsb_get(sdp, make_kqid_gid(ip->i_inode.i_gid), qd);
557         if (error)
558                 goto out;
559         ip->i_res->rs_qa_qd_num++;
560         qd++;
561
562         if (!uid_eq(uid, NO_UID_QUOTA_CHANGE) &&
563             !uid_eq(uid, ip->i_inode.i_uid)) {
564                 error = qdsb_get(sdp, make_kqid_uid(uid), qd);
565                 if (error)
566                         goto out;
567                 ip->i_res->rs_qa_qd_num++;
568                 qd++;
569         }
570
571         if (!gid_eq(gid, NO_GID_QUOTA_CHANGE) &&
572             !gid_eq(gid, ip->i_inode.i_gid)) {
573                 error = qdsb_get(sdp, make_kqid_gid(gid), qd);
574                 if (error)
575                         goto out;
576                 ip->i_res->rs_qa_qd_num++;
577                 qd++;
578         }
579
580 out:
581         if (error)
582                 gfs2_quota_unhold(ip);
583         return error;
584 }
585
586 void gfs2_quota_unhold(struct gfs2_inode *ip)
587 {
588         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
589         unsigned int x;
590
591         if (ip->i_res == NULL)
592                 return;
593         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
594
595         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
596                 qdsb_put(ip->i_res->rs_qa_qd[x]);
597                 ip->i_res->rs_qa_qd[x] = NULL;
598         }
599         ip->i_res->rs_qa_qd_num = 0;
600 }
601
602 static int sort_qd(const void *a, const void *b)
603 {
604         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
605         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
606
607         if (qid_lt(qd_a->qd_id, qd_b->qd_id))
608                 return -1;
609         if (qid_lt(qd_b->qd_id, qd_a->qd_id))
610                 return 1;
611         return 0;
612 }
613
614 static void do_qc(struct gfs2_quota_data *qd, s64 change)
615 {
616         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
617         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
618         struct gfs2_quota_change *qc = qd->qd_bh_qc;
619         s64 x;
620
621         mutex_lock(&sdp->sd_quota_mutex);
622         gfs2_trans_add_meta(ip->i_gl, qd->qd_bh);
623
624         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
625                 qc->qc_change = 0;
626                 qc->qc_flags = 0;
627                 if (qd->qd_id.type == USRQUOTA)
628                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
629                 qc->qc_id = cpu_to_be32(from_kqid(&init_user_ns, qd->qd_id));
630         }
631
632         x = be64_to_cpu(qc->qc_change) + change;
633         qc->qc_change = cpu_to_be64(x);
634
635         spin_lock(&qd_lock);
636         qd->qd_change = x;
637         spin_unlock(&qd_lock);
638
639         if (!x) {
640                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
641                 clear_bit(QDF_CHANGE, &qd->qd_flags);
642                 qc->qc_flags = 0;
643                 qc->qc_id = 0;
644                 slot_put(qd);
645                 qd_put(qd);
646         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
647                 qd_hold(qd);
648                 slot_hold(qd);
649         }
650
651         mutex_unlock(&sdp->sd_quota_mutex);
652 }
653
654 /**
655  * gfs2_adjust_quota - adjust record of current block usage
656  * @ip: The quota inode
657  * @loc: Offset of the entry in the quota file
658  * @change: The amount of usage change to record
659  * @qd: The quota data
660  * @fdq: The updated limits to record
661  *
662  * This function was mostly borrowed from gfs2_block_truncate_page which was
663  * in turn mostly borrowed from ext3
664  *
665  * Returns: 0 or -ve on error
666  */
667
668 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
669                              s64 change, struct gfs2_quota_data *qd,
670                              struct qc_dqblk *fdq)
671 {
672         struct inode *inode = &ip->i_inode;
673         struct gfs2_sbd *sdp = GFS2_SB(inode);
674         struct address_space *mapping = inode->i_mapping;
675         unsigned long index = loc >> PAGE_CACHE_SHIFT;
676         unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
677         unsigned blocksize, iblock, pos;
678         struct buffer_head *bh;
679         struct page *page;
680         void *kaddr, *ptr;
681         struct gfs2_quota q;
682         int err, nbytes;
683         u64 size;
684
685         if (gfs2_is_stuffed(ip)) {
686                 err = gfs2_unstuff_dinode(ip, NULL);
687                 if (err)
688                         return err;
689         }
690
691         memset(&q, 0, sizeof(struct gfs2_quota));
692         err = gfs2_internal_read(ip, (char *)&q, &loc, sizeof(q));
693         if (err < 0)
694                 return err;
695
696         err = -EIO;
697         be64_add_cpu(&q.qu_value, change);
698         qd->qd_qb.qb_value = q.qu_value;
699         if (fdq) {
700                 if (fdq->d_fieldmask & QC_SPC_SOFT) {
701                         q.qu_warn = cpu_to_be64(fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift);
702                         qd->qd_qb.qb_warn = q.qu_warn;
703                 }
704                 if (fdq->d_fieldmask & QC_SPC_HARD) {
705                         q.qu_limit = cpu_to_be64(fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift);
706                         qd->qd_qb.qb_limit = q.qu_limit;
707                 }
708                 if (fdq->d_fieldmask & QC_SPACE) {
709                         q.qu_value = cpu_to_be64(fdq->d_space >> sdp->sd_sb.sb_bsize_shift);
710                         qd->qd_qb.qb_value = q.qu_value;
711                 }
712         }
713
714         /* Write the quota into the quota file on disk */
715         ptr = &q;
716         nbytes = sizeof(struct gfs2_quota);
717 get_a_page:
718         page = find_or_create_page(mapping, index, GFP_NOFS);
719         if (!page)
720                 return -ENOMEM;
721
722         blocksize = inode->i_sb->s_blocksize;
723         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
724
725         if (!page_has_buffers(page))
726                 create_empty_buffers(page, blocksize, 0);
727
728         bh = page_buffers(page);
729         pos = blocksize;
730         while (offset >= pos) {
731                 bh = bh->b_this_page;
732                 iblock++;
733                 pos += blocksize;
734         }
735
736         if (!buffer_mapped(bh)) {
737                 gfs2_block_map(inode, iblock, bh, 1);
738                 if (!buffer_mapped(bh))
739                         goto unlock_out;
740                 /* If it's a newly allocated disk block for quota, zero it */
741                 if (buffer_new(bh))
742                         zero_user(page, pos - blocksize, bh->b_size);
743         }
744
745         if (PageUptodate(page))
746                 set_buffer_uptodate(bh);
747
748         if (!buffer_uptodate(bh)) {
749                 ll_rw_block(READ | REQ_META, 1, &bh);
750                 wait_on_buffer(bh);
751                 if (!buffer_uptodate(bh))
752                         goto unlock_out;
753         }
754
755         gfs2_trans_add_data(ip->i_gl, bh);
756
757         kaddr = kmap_atomic(page);
758         if (offset + sizeof(struct gfs2_quota) > PAGE_CACHE_SIZE)
759                 nbytes = PAGE_CACHE_SIZE - offset;
760         memcpy(kaddr + offset, ptr, nbytes);
761         flush_dcache_page(page);
762         kunmap_atomic(kaddr);
763         unlock_page(page);
764         page_cache_release(page);
765
766         /* If quota straddles page boundary, we need to update the rest of the
767          * quota at the beginning of the next page */
768         if ((offset + sizeof(struct gfs2_quota)) > PAGE_CACHE_SIZE) {
769                 ptr = ptr + nbytes;
770                 nbytes = sizeof(struct gfs2_quota) - nbytes;
771                 offset = 0;
772                 index++;
773                 goto get_a_page;
774         }
775
776         size = loc + sizeof(struct gfs2_quota);
777         if (size > inode->i_size)
778                 i_size_write(inode, size);
779         inode->i_mtime = inode->i_atime = CURRENT_TIME;
780         mark_inode_dirty(inode);
781         set_bit(QDF_REFRESH, &qd->qd_flags);
782         return 0;
783
784 unlock_out:
785         unlock_page(page);
786         page_cache_release(page);
787         return err;
788 }
789
790 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
791 {
792         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
793         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
794         struct gfs2_alloc_parms ap = { .aflags = 0, };
795         unsigned int data_blocks, ind_blocks;
796         struct gfs2_holder *ghs, i_gh;
797         unsigned int qx, x;
798         struct gfs2_quota_data *qd;
799         unsigned reserved;
800         loff_t offset;
801         unsigned int nalloc = 0, blocks;
802         int error;
803
804         error = gfs2_rs_alloc(ip);
805         if (error)
806                 return error;
807
808         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
809                               &data_blocks, &ind_blocks);
810
811         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
812         if (!ghs)
813                 return -ENOMEM;
814
815         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
816         mutex_lock(&ip->i_inode.i_mutex);
817         for (qx = 0; qx < num_qd; qx++) {
818                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
819                                            GL_NOCACHE, &ghs[qx]);
820                 if (error)
821                         goto out;
822         }
823
824         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
825         if (error)
826                 goto out;
827
828         for (x = 0; x < num_qd; x++) {
829                 offset = qd2offset(qda[x]);
830                 if (gfs2_write_alloc_required(ip, offset,
831                                               sizeof(struct gfs2_quota)))
832                         nalloc++;
833         }
834
835         /* 
836          * 1 blk for unstuffing inode if stuffed. We add this extra
837          * block to the reservation unconditionally. If the inode
838          * doesn't need unstuffing, the block will be released to the 
839          * rgrp since it won't be allocated during the transaction
840          */
841         /* +3 in the end for unstuffing block, inode size update block
842          * and another block in case quota straddles page boundary and 
843          * two blocks need to be updated instead of 1 */
844         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
845
846         reserved = 1 + (nalloc * (data_blocks + ind_blocks));
847         ap.target = reserved;
848         error = gfs2_inplace_reserve(ip, &ap);
849         if (error)
850                 goto out_alloc;
851
852         if (nalloc)
853                 blocks += gfs2_rg_blocks(ip, reserved) + nalloc * ind_blocks + RES_STATFS;
854
855         error = gfs2_trans_begin(sdp, blocks, 0);
856         if (error)
857                 goto out_ipres;
858
859         for (x = 0; x < num_qd; x++) {
860                 qd = qda[x];
861                 offset = qd2offset(qd);
862                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
863                 if (error)
864                         goto out_end_trans;
865
866                 do_qc(qd, -qd->qd_change_sync);
867                 set_bit(QDF_REFRESH, &qd->qd_flags);
868         }
869
870         error = 0;
871
872 out_end_trans:
873         gfs2_trans_end(sdp);
874 out_ipres:
875         gfs2_inplace_release(ip);
876 out_alloc:
877         gfs2_glock_dq_uninit(&i_gh);
878 out:
879         while (qx--)
880                 gfs2_glock_dq_uninit(&ghs[qx]);
881         mutex_unlock(&ip->i_inode.i_mutex);
882         kfree(ghs);
883         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl, NORMAL_FLUSH);
884         return error;
885 }
886
887 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
888 {
889         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
890         struct gfs2_quota q;
891         struct gfs2_quota_lvb *qlvb;
892         loff_t pos;
893         int error;
894
895         memset(&q, 0, sizeof(struct gfs2_quota));
896         pos = qd2offset(qd);
897         error = gfs2_internal_read(ip, (char *)&q, &pos, sizeof(q));
898         if (error < 0)
899                 return error;
900
901         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
902         qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
903         qlvb->__pad = 0;
904         qlvb->qb_limit = q.qu_limit;
905         qlvb->qb_warn = q.qu_warn;
906         qlvb->qb_value = q.qu_value;
907         qd->qd_qb = *qlvb;
908
909         return 0;
910 }
911
912 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
913                     struct gfs2_holder *q_gh)
914 {
915         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
916         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
917         struct gfs2_holder i_gh;
918         int error;
919
920 restart:
921         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
922         if (error)
923                 return error;
924
925         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
926
927         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
928                 gfs2_glock_dq_uninit(q_gh);
929                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
930                                            GL_NOCACHE, q_gh);
931                 if (error)
932                         return error;
933
934                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
935                 if (error)
936                         goto fail;
937
938                 error = update_qd(sdp, qd);
939                 if (error)
940                         goto fail_gunlock;
941
942                 gfs2_glock_dq_uninit(&i_gh);
943                 gfs2_glock_dq_uninit(q_gh);
944                 force_refresh = 0;
945                 goto restart;
946         }
947
948         return 0;
949
950 fail_gunlock:
951         gfs2_glock_dq_uninit(&i_gh);
952 fail:
953         gfs2_glock_dq_uninit(q_gh);
954         return error;
955 }
956
957 int gfs2_quota_lock(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
958 {
959         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
960         struct gfs2_quota_data *qd;
961         unsigned int x;
962         int error = 0;
963
964         error = gfs2_quota_hold(ip, uid, gid);
965         if (error)
966                 return error;
967
968         if (capable(CAP_SYS_RESOURCE) ||
969             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
970                 return 0;
971
972         sort(ip->i_res->rs_qa_qd, ip->i_res->rs_qa_qd_num,
973              sizeof(struct gfs2_quota_data *), sort_qd, NULL);
974
975         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
976                 int force = NO_FORCE;
977                 qd = ip->i_res->rs_qa_qd[x];
978                 if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
979                         force = FORCE;
980                 error = do_glock(qd, force, &ip->i_res->rs_qa_qd_ghs[x]);
981                 if (error)
982                         break;
983         }
984
985         if (!error)
986                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
987         else {
988                 while (x--)
989                         gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
990                 gfs2_quota_unhold(ip);
991         }
992
993         return error;
994 }
995
996 static int need_sync(struct gfs2_quota_data *qd)
997 {
998         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
999         struct gfs2_tune *gt = &sdp->sd_tune;
1000         s64 value;
1001         unsigned int num, den;
1002         int do_sync = 1;
1003
1004         if (!qd->qd_qb.qb_limit)
1005                 return 0;
1006
1007         spin_lock(&qd_lock);
1008         value = qd->qd_change;
1009         spin_unlock(&qd_lock);
1010
1011         spin_lock(&gt->gt_spin);
1012         num = gt->gt_quota_scale_num;
1013         den = gt->gt_quota_scale_den;
1014         spin_unlock(&gt->gt_spin);
1015
1016         if (value < 0)
1017                 do_sync = 0;
1018         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
1019                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1020                 do_sync = 0;
1021         else {
1022                 value *= gfs2_jindex_size(sdp) * num;
1023                 value = div_s64(value, den);
1024                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
1025                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1026                         do_sync = 0;
1027         }
1028
1029         return do_sync;
1030 }
1031
1032 void gfs2_quota_unlock(struct gfs2_inode *ip)
1033 {
1034         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1035         struct gfs2_quota_data *qda[4];
1036         unsigned int count = 0;
1037         unsigned int x;
1038         int found;
1039
1040         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1041                 goto out;
1042
1043         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1044                 struct gfs2_quota_data *qd;
1045                 int sync;
1046
1047                 qd = ip->i_res->rs_qa_qd[x];
1048                 sync = need_sync(qd);
1049
1050                 gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
1051                 if (!sync)
1052                         continue;
1053
1054                 spin_lock(&qd_lock);
1055                 found = qd_check_sync(sdp, qd, NULL);
1056                 spin_unlock(&qd_lock);
1057
1058                 if (!found)
1059                         continue;
1060
1061                 gfs2_assert_warn(sdp, qd->qd_change_sync);
1062                 if (bh_get(qd)) {
1063                         clear_bit(QDF_LOCKED, &qd->qd_flags);
1064                         slot_put(qd);
1065                         qd_put(qd);
1066                         continue;
1067                 }
1068
1069                 qda[count++] = qd;
1070         }
1071
1072         if (count) {
1073                 do_sync(count, qda);
1074                 for (x = 0; x < count; x++)
1075                         qd_unlock(qda[x]);
1076         }
1077
1078 out:
1079         gfs2_quota_unhold(ip);
1080 }
1081
1082 #define MAX_LINE 256
1083
1084 static int print_message(struct gfs2_quota_data *qd, char *type)
1085 {
1086         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
1087
1088         fs_info(sdp, "quota %s for %s %u\n",
1089                 type,
1090                 (qd->qd_id.type == USRQUOTA) ? "user" : "group",
1091                 from_kqid(&init_user_ns, qd->qd_id));
1092
1093         return 0;
1094 }
1095
1096 int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
1097 {
1098         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1099         struct gfs2_quota_data *qd;
1100         s64 value;
1101         unsigned int x;
1102         int error = 0;
1103
1104         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1105                 return 0;
1106
1107         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1108                 return 0;
1109
1110         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1111                 qd = ip->i_res->rs_qa_qd[x];
1112
1113                 if (!(qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1114                       qid_eq(qd->qd_id, make_kqid_gid(gid))))
1115                         continue;
1116
1117                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1118                 spin_lock(&qd_lock);
1119                 value += qd->qd_change;
1120                 spin_unlock(&qd_lock);
1121
1122                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
1123                         print_message(qd, "exceeded");
1124                         quota_send_warning(qd->qd_id,
1125                                            sdp->sd_vfs->s_dev, QUOTA_NL_BHARDWARN);
1126
1127                         error = -EDQUOT;
1128                         break;
1129                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
1130                            (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
1131                            time_after_eq(jiffies, qd->qd_last_warn +
1132                                          gfs2_tune_get(sdp,
1133                                                 gt_quota_warn_period) * HZ)) {
1134                         quota_send_warning(qd->qd_id,
1135                                            sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1136                         error = print_message(qd, "warning");
1137                         qd->qd_last_warn = jiffies;
1138                 }
1139         }
1140
1141         return error;
1142 }
1143
1144 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1145                        kuid_t uid, kgid_t gid)
1146 {
1147         struct gfs2_quota_data *qd;
1148         unsigned int x;
1149
1150         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1151                 return;
1152         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1153                 return;
1154
1155         for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1156                 qd = ip->i_res->rs_qa_qd[x];
1157
1158                 if (qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1159                     qid_eq(qd->qd_id, make_kqid_gid(gid))) {
1160                         do_qc(qd, change);
1161                 }
1162         }
1163 }
1164
1165 int gfs2_quota_sync(struct super_block *sb, int type)
1166 {
1167         struct gfs2_sbd *sdp = sb->s_fs_info;
1168         struct gfs2_quota_data **qda;
1169         unsigned int max_qd = PAGE_SIZE/sizeof(struct gfs2_holder);
1170         unsigned int num_qd;
1171         unsigned int x;
1172         int error = 0;
1173
1174         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1175         if (!qda)
1176                 return -ENOMEM;
1177
1178         mutex_lock(&sdp->sd_quota_sync_mutex);
1179         sdp->sd_quota_sync_gen++;
1180
1181         do {
1182                 num_qd = 0;
1183
1184                 for (;;) {
1185                         error = qd_fish(sdp, qda + num_qd);
1186                         if (error || !qda[num_qd])
1187                                 break;
1188                         if (++num_qd == max_qd)
1189                                 break;
1190                 }
1191
1192                 if (num_qd) {
1193                         if (!error)
1194                                 error = do_sync(num_qd, qda);
1195                         if (!error)
1196                                 for (x = 0; x < num_qd; x++)
1197                                         qda[x]->qd_sync_gen =
1198                                                 sdp->sd_quota_sync_gen;
1199
1200                         for (x = 0; x < num_qd; x++)
1201                                 qd_unlock(qda[x]);
1202                 }
1203         } while (!error && num_qd == max_qd);
1204
1205         mutex_unlock(&sdp->sd_quota_sync_mutex);
1206         kfree(qda);
1207
1208         return error;
1209 }
1210
1211 int gfs2_quota_refresh(struct gfs2_sbd *sdp, struct kqid qid)
1212 {
1213         struct gfs2_quota_data *qd;
1214         struct gfs2_holder q_gh;
1215         int error;
1216
1217         error = qd_get(sdp, qid, &qd);
1218         if (error)
1219                 return error;
1220
1221         error = do_glock(qd, FORCE, &q_gh);
1222         if (!error)
1223                 gfs2_glock_dq_uninit(&q_gh);
1224
1225         qd_put(qd);
1226         return error;
1227 }
1228
1229 int gfs2_quota_init(struct gfs2_sbd *sdp)
1230 {
1231         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1232         u64 size = i_size_read(sdp->sd_qc_inode);
1233         unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1234         unsigned int x, slot = 0;
1235         unsigned int found = 0;
1236         unsigned int hash;
1237         unsigned int bm_size;
1238         u64 dblock;
1239         u32 extlen = 0;
1240         int error;
1241
1242         if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1243                 return -EIO;
1244
1245         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1246         bm_size = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * sizeof(unsigned long));
1247         bm_size *= sizeof(unsigned long);
1248         error = -ENOMEM;
1249         sdp->sd_quota_bitmap = kzalloc(bm_size, GFP_NOFS | __GFP_NOWARN);
1250         if (sdp->sd_quota_bitmap == NULL)
1251                 sdp->sd_quota_bitmap = __vmalloc(bm_size, GFP_NOFS |
1252                                                  __GFP_ZERO, PAGE_KERNEL);
1253         if (!sdp->sd_quota_bitmap)
1254                 return error;
1255
1256         for (x = 0; x < blocks; x++) {
1257                 struct buffer_head *bh;
1258                 const struct gfs2_quota_change *qc;
1259                 unsigned int y;
1260
1261                 if (!extlen) {
1262                         int new = 0;
1263                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1264                         if (error)
1265                                 goto fail;
1266                 }
1267                 error = -EIO;
1268                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1269                 if (!bh)
1270                         goto fail;
1271                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1272                         brelse(bh);
1273                         goto fail;
1274                 }
1275
1276                 qc = (const struct gfs2_quota_change *)(bh->b_data + sizeof(struct gfs2_meta_header));
1277                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1278                      y++, slot++) {
1279                         struct gfs2_quota_data *qd;
1280                         s64 qc_change = be64_to_cpu(qc->qc_change);
1281                         u32 qc_flags = be32_to_cpu(qc->qc_flags);
1282                         enum quota_type qtype = (qc_flags & GFS2_QCF_USER) ?
1283                                                 USRQUOTA : GRPQUOTA;
1284                         struct kqid qc_id = make_kqid(&init_user_ns, qtype,
1285                                                       be32_to_cpu(qc->qc_id));
1286                         qc++;
1287                         if (!qc_change)
1288                                 continue;
1289
1290                         hash = gfs2_qd_hash(sdp, qc_id);
1291                         qd = qd_alloc(hash, sdp, qc_id);
1292                         if (qd == NULL) {
1293                                 brelse(bh);
1294                                 goto fail;
1295                         }
1296
1297                         set_bit(QDF_CHANGE, &qd->qd_flags);
1298                         qd->qd_change = qc_change;
1299                         qd->qd_slot = slot;
1300                         qd->qd_slot_count = 1;
1301
1302                         spin_lock(&qd_lock);
1303                         BUG_ON(test_and_set_bit(slot, sdp->sd_quota_bitmap));
1304                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1305                         atomic_inc(&sdp->sd_quota_count);
1306                         spin_unlock(&qd_lock);
1307
1308                         spin_lock_bucket(hash);
1309                         hlist_bl_add_head_rcu(&qd->qd_hlist, &qd_hash_table[hash]);
1310                         spin_unlock_bucket(hash);
1311
1312                         found++;
1313                 }
1314
1315                 brelse(bh);
1316                 dblock++;
1317                 extlen--;
1318         }
1319
1320         if (found)
1321                 fs_info(sdp, "found %u quota changes\n", found);
1322
1323         return 0;
1324
1325 fail:
1326         gfs2_quota_cleanup(sdp);
1327         return error;
1328 }
1329
1330 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1331 {
1332         struct list_head *head = &sdp->sd_quota_list;
1333         struct gfs2_quota_data *qd;
1334
1335         spin_lock(&qd_lock);
1336         while (!list_empty(head)) {
1337                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1338
1339                 list_del(&qd->qd_list);
1340
1341                 /* Also remove if this qd exists in the reclaim list */
1342                 list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
1343                 atomic_dec(&sdp->sd_quota_count);
1344                 spin_unlock(&qd_lock);
1345
1346                 spin_lock_bucket(qd->qd_hash);
1347                 hlist_bl_del_rcu(&qd->qd_hlist);
1348                 spin_unlock_bucket(qd->qd_hash);
1349
1350                 gfs2_assert_warn(sdp, !qd->qd_change);
1351                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1352                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1353
1354                 gfs2_glock_put(qd->qd_gl);
1355                 call_rcu(&qd->qd_rcu, gfs2_qd_dealloc);
1356
1357                 spin_lock(&qd_lock);
1358         }
1359         spin_unlock(&qd_lock);
1360
1361         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1362
1363         kvfree(sdp->sd_quota_bitmap);
1364         sdp->sd_quota_bitmap = NULL;
1365 }
1366
1367 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1368 {
1369         if (error == 0 || error == -EROFS)
1370                 return;
1371         if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1372                 fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1373 }
1374
1375 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1376                                int (*fxn)(struct super_block *sb, int type),
1377                                unsigned long t, unsigned long *timeo,
1378                                unsigned int *new_timeo)
1379 {
1380         if (t >= *timeo) {
1381                 int error = fxn(sdp->sd_vfs, 0);
1382                 quotad_error(sdp, msg, error);
1383                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1384         } else {
1385                 *timeo -= t;
1386         }
1387 }
1388
1389 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1390 {
1391         struct gfs2_inode *ip;
1392
1393         while(1) {
1394                 ip = NULL;
1395                 spin_lock(&sdp->sd_trunc_lock);
1396                 if (!list_empty(&sdp->sd_trunc_list)) {
1397                         ip = list_entry(sdp->sd_trunc_list.next,
1398                                         struct gfs2_inode, i_trunc_list);
1399                         list_del_init(&ip->i_trunc_list);
1400                 }
1401                 spin_unlock(&sdp->sd_trunc_lock);
1402                 if (ip == NULL)
1403                         return;
1404                 gfs2_glock_finish_truncate(ip);
1405         }
1406 }
1407
1408 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1409         if (!sdp->sd_statfs_force_sync) {
1410                 sdp->sd_statfs_force_sync = 1;
1411                 wake_up(&sdp->sd_quota_wait);
1412         }
1413 }
1414
1415
1416 /**
1417  * gfs2_quotad - Write cached quota changes into the quota file
1418  * @sdp: Pointer to GFS2 superblock
1419  *
1420  */
1421
1422 int gfs2_quotad(void *data)
1423 {
1424         struct gfs2_sbd *sdp = data;
1425         struct gfs2_tune *tune = &sdp->sd_tune;
1426         unsigned long statfs_timeo = 0;
1427         unsigned long quotad_timeo = 0;
1428         unsigned long t = 0;
1429         DEFINE_WAIT(wait);
1430         int empty;
1431
1432         while (!kthread_should_stop()) {
1433
1434                 /* Update the master statfs file */
1435                 if (sdp->sd_statfs_force_sync) {
1436                         int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1437                         quotad_error(sdp, "statfs", error);
1438                         statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1439                 }
1440                 else
1441                         quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1442                                            &statfs_timeo,
1443                                            &tune->gt_statfs_quantum);
1444
1445                 /* Update quota file */
1446                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
1447                                    &quotad_timeo, &tune->gt_quota_quantum);
1448
1449                 /* Check for & recover partially truncated inodes */
1450                 quotad_check_trunc_list(sdp);
1451
1452                 try_to_freeze();
1453
1454                 t = min(quotad_timeo, statfs_timeo);
1455
1456                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1457                 spin_lock(&sdp->sd_trunc_lock);
1458                 empty = list_empty(&sdp->sd_trunc_list);
1459                 spin_unlock(&sdp->sd_trunc_lock);
1460                 if (empty && !sdp->sd_statfs_force_sync)
1461                         t -= schedule_timeout(t);
1462                 else
1463                         t = 0;
1464                 finish_wait(&sdp->sd_quota_wait, &wait);
1465         }
1466
1467         return 0;
1468 }
1469
1470 static int gfs2_quota_get_xstate(struct super_block *sb,
1471                                  struct fs_quota_stat *fqs)
1472 {
1473         struct gfs2_sbd *sdp = sb->s_fs_info;
1474
1475         memset(fqs, 0, sizeof(struct fs_quota_stat));
1476         fqs->qs_version = FS_QSTAT_VERSION;
1477
1478         switch (sdp->sd_args.ar_quota) {
1479         case GFS2_QUOTA_ON:
1480                 fqs->qs_flags |= (FS_QUOTA_UDQ_ENFD | FS_QUOTA_GDQ_ENFD);
1481                 /*FALLTHRU*/
1482         case GFS2_QUOTA_ACCOUNT:
1483                 fqs->qs_flags |= (FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT);
1484                 break;
1485         case GFS2_QUOTA_OFF:
1486                 break;
1487         }
1488
1489         if (sdp->sd_quota_inode) {
1490                 fqs->qs_uquota.qfs_ino = GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1491                 fqs->qs_uquota.qfs_nblks = sdp->sd_quota_inode->i_blocks;
1492         }
1493         fqs->qs_uquota.qfs_nextents = 1; /* unsupported */
1494         fqs->qs_gquota = fqs->qs_uquota; /* its the same inode in both cases */
1495         fqs->qs_incoredqs = list_lru_count(&gfs2_qd_lru);
1496         return 0;
1497 }
1498
1499 static int gfs2_get_dqblk(struct super_block *sb, struct kqid qid,
1500                           struct qc_dqblk *fdq)
1501 {
1502         struct gfs2_sbd *sdp = sb->s_fs_info;
1503         struct gfs2_quota_lvb *qlvb;
1504         struct gfs2_quota_data *qd;
1505         struct gfs2_holder q_gh;
1506         int error;
1507
1508         memset(fdq, 0, sizeof(*fdq));
1509
1510         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1511                 return -ESRCH; /* Crazy XFS error code */
1512
1513         if ((qid.type != USRQUOTA) &&
1514             (qid.type != GRPQUOTA))
1515                 return -EINVAL;
1516
1517         error = qd_get(sdp, qid, &qd);
1518         if (error)
1519                 return error;
1520         error = do_glock(qd, FORCE, &q_gh);
1521         if (error)
1522                 goto out;
1523
1524         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1525         fdq->d_spc_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_sb.sb_bsize_shift;
1526         fdq->d_spc_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_sb.sb_bsize_shift;
1527         fdq->d_space = be64_to_cpu(qlvb->qb_value) << sdp->sd_sb.sb_bsize_shift;
1528
1529         gfs2_glock_dq_uninit(&q_gh);
1530 out:
1531         qd_put(qd);
1532         return error;
1533 }
1534
1535 /* GFS2 only supports a subset of the XFS fields */
1536 #define GFS2_FIELDMASK (QC_SPC_SOFT|QC_SPC_HARD|QC_SPACE)
1537
1538 static int gfs2_set_dqblk(struct super_block *sb, struct kqid qid,
1539                           struct qc_dqblk *fdq)
1540 {
1541         struct gfs2_sbd *sdp = sb->s_fs_info;
1542         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1543         struct gfs2_quota_data *qd;
1544         struct gfs2_holder q_gh, i_gh;
1545         unsigned int data_blocks, ind_blocks;
1546         unsigned int blocks = 0;
1547         int alloc_required;
1548         loff_t offset;
1549         int error;
1550
1551         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1552                 return -ESRCH; /* Crazy XFS error code */
1553
1554         if ((qid.type != USRQUOTA) &&
1555             (qid.type != GRPQUOTA))
1556                 return -EINVAL;
1557
1558         if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1559                 return -EINVAL;
1560
1561         error = qd_get(sdp, qid, &qd);
1562         if (error)
1563                 return error;
1564
1565         error = gfs2_rs_alloc(ip);
1566         if (error)
1567                 goto out_put;
1568
1569         mutex_lock(&ip->i_inode.i_mutex);
1570         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1571         if (error)
1572                 goto out_unlockput;
1573         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1574         if (error)
1575                 goto out_q;
1576
1577         /* Check for existing entry, if none then alloc new blocks */
1578         error = update_qd(sdp, qd);
1579         if (error)
1580                 goto out_i;
1581
1582         /* If nothing has changed, this is a no-op */
1583         if ((fdq->d_fieldmask & QC_SPC_SOFT) &&
1584             ((fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1585                 fdq->d_fieldmask ^= QC_SPC_SOFT;
1586
1587         if ((fdq->d_fieldmask & QC_SPC_HARD) &&
1588             ((fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1589                 fdq->d_fieldmask ^= QC_SPC_HARD;
1590
1591         if ((fdq->d_fieldmask & QC_SPACE) &&
1592             ((fdq->d_space >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1593                 fdq->d_fieldmask ^= QC_SPACE;
1594
1595         if (fdq->d_fieldmask == 0)
1596                 goto out_i;
1597
1598         offset = qd2offset(qd);
1599         alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1600         if (gfs2_is_stuffed(ip))
1601                 alloc_required = 1;
1602         if (alloc_required) {
1603                 struct gfs2_alloc_parms ap = { .aflags = 0, };
1604                 gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1605                                        &data_blocks, &ind_blocks);
1606                 blocks = 1 + data_blocks + ind_blocks;
1607                 ap.target = blocks;
1608                 error = gfs2_inplace_reserve(ip, &ap);
1609                 if (error)
1610                         goto out_i;
1611                 blocks += gfs2_rg_blocks(ip, blocks);
1612         }
1613
1614         /* Some quotas span block boundaries and can update two blocks,
1615            adding an extra block to the transaction to handle such quotas */
1616         error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1617         if (error)
1618                 goto out_release;
1619
1620         /* Apply changes */
1621         error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1622
1623         gfs2_trans_end(sdp);
1624 out_release:
1625         if (alloc_required)
1626                 gfs2_inplace_release(ip);
1627 out_i:
1628         gfs2_glock_dq_uninit(&i_gh);
1629 out_q:
1630         gfs2_glock_dq_uninit(&q_gh);
1631 out_unlockput:
1632         mutex_unlock(&ip->i_inode.i_mutex);
1633 out_put:
1634         qd_put(qd);
1635         return error;
1636 }
1637
1638 const struct quotactl_ops gfs2_quotactl_ops = {
1639         .quota_sync     = gfs2_quota_sync,
1640         .get_xstate     = gfs2_quota_get_xstate,
1641         .get_dqblk      = gfs2_get_dqblk,
1642         .set_dqblk      = gfs2_set_dqblk,
1643 };
1644
1645 void __init gfs2_quota_hash_init(void)
1646 {
1647         unsigned i;
1648
1649         for(i = 0; i < GFS2_QD_HASH_SIZE; i++)
1650                 INIT_HLIST_BL_HEAD(&qd_hash_table[i]);
1651 }