Merge tag 'microblaze-v6.6' of git://git.monstr.eu/linux-2.6-microblaze
[platform/kernel/linux-rpi.git] / fs / gfs2 / quota.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
4  * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
5  */
6
7 /*
8  * Quota change tags are associated with each transaction that allocates or
9  * deallocates space.  Those changes are accumulated locally to each node (in a
10  * per-node file) and then are periodically synced to the quota file.  This
11  * avoids the bottleneck of constantly touching the quota file, but introduces
12  * fuzziness in the current usage value of IDs that are being used on different
13  * nodes in the cluster simultaneously.  So, it is possible for a user on
14  * multiple nodes to overrun their quota, but that overrun is controlable.
15  * Since quota tags are part of transactions, there is no need for a quota check
16  * program to be run on node crashes or anything like that.
17  *
18  * There are couple of knobs that let the administrator manage the quota
19  * fuzziness.  "quota_quantum" sets the maximum time a quota change can be
20  * sitting on one node before being synced to the quota file.  (The default is
21  * 60 seconds.)  Another knob, "quota_scale" controls how quickly the frequency
22  * of quota file syncs increases as the user moves closer to their limit.  The
23  * more frequent the syncs, the more accurate the quota enforcement, but that
24  * means that there is more contention between the nodes for the quota file.
25  * The default value is one.  This sets the maximum theoretical quota overrun
26  * (with infinite node with infinite bandwidth) to twice the user's limit.  (In
27  * practice, the maximum overrun you see should be much less.)  A "quota_scale"
28  * number greater than one makes quota syncs more frequent and reduces the
29  * maximum overrun.  Numbers less than one (but greater than zero) make quota
30  * syncs less frequent.
31  *
32  * GFS quotas also use per-ID Lock Value Blocks (LVBs) to cache the contents of
33  * the quota file, so it is not being constantly read.
34  */
35
36 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
37
38 #include <linux/sched.h>
39 #include <linux/slab.h>
40 #include <linux/mm.h>
41 #include <linux/spinlock.h>
42 #include <linux/completion.h>
43 #include <linux/buffer_head.h>
44 #include <linux/sort.h>
45 #include <linux/fs.h>
46 #include <linux/bio.h>
47 #include <linux/gfs2_ondisk.h>
48 #include <linux/kthread.h>
49 #include <linux/freezer.h>
50 #include <linux/quota.h>
51 #include <linux/dqblk_xfs.h>
52 #include <linux/lockref.h>
53 #include <linux/list_lru.h>
54 #include <linux/rcupdate.h>
55 #include <linux/rculist_bl.h>
56 #include <linux/bit_spinlock.h>
57 #include <linux/jhash.h>
58 #include <linux/vmalloc.h>
59
60 #include "gfs2.h"
61 #include "incore.h"
62 #include "bmap.h"
63 #include "glock.h"
64 #include "glops.h"
65 #include "log.h"
66 #include "meta_io.h"
67 #include "quota.h"
68 #include "rgrp.h"
69 #include "super.h"
70 #include "trans.h"
71 #include "inode.h"
72 #include "util.h"
73
74 #define GFS2_QD_HASH_SHIFT      12
75 #define GFS2_QD_HASH_SIZE       BIT(GFS2_QD_HASH_SHIFT)
76 #define GFS2_QD_HASH_MASK       (GFS2_QD_HASH_SIZE - 1)
77
78 #define QC_CHANGE 0
79 #define QC_SYNC 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_first_entry(list, struct gfs2_quota_data, qd_lru);
122                 sdp = qd->qd_gl->gl_name.ln_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,
149                 struct list_lru_one *lru, spinlock_t *lru_lock, void *arg)
150 {
151         struct list_head *dispose = arg;
152         struct gfs2_quota_data *qd = list_entry(item, struct gfs2_quota_data, qd_lru);
153
154         if (!spin_trylock(&qd->qd_lockref.lock))
155                 return LRU_SKIP;
156
157         if (qd->qd_lockref.count == 0) {
158                 lockref_mark_dead(&qd->qd_lockref);
159                 list_lru_isolate_move(lru, &qd->qd_lru, dispose);
160         }
161
162         spin_unlock(&qd->qd_lockref.lock);
163         return LRU_REMOVED;
164 }
165
166 static unsigned long gfs2_qd_shrink_scan(struct shrinker *shrink,
167                                          struct shrink_control *sc)
168 {
169         LIST_HEAD(dispose);
170         unsigned long freed;
171
172         if (!(sc->gfp_mask & __GFP_FS))
173                 return SHRINK_STOP;
174
175         freed = list_lru_shrink_walk(&gfs2_qd_lru, sc,
176                                      gfs2_qd_isolate, &dispose);
177
178         gfs2_qd_dispose(&dispose);
179
180         return freed;
181 }
182
183 static unsigned long gfs2_qd_shrink_count(struct shrinker *shrink,
184                                           struct shrink_control *sc)
185 {
186         return vfs_pressure_ratio(list_lru_shrink_count(&gfs2_qd_lru, sc));
187 }
188
189 struct shrinker gfs2_qd_shrinker = {
190         .count_objects = gfs2_qd_shrink_count,
191         .scan_objects = gfs2_qd_shrink_scan,
192         .seeks = DEFAULT_SEEKS,
193         .flags = SHRINKER_NUMA_AWARE,
194 };
195
196
197 static u64 qd2index(struct gfs2_quota_data *qd)
198 {
199         struct kqid qid = qd->qd_id;
200         return (2 * (u64)from_kqid(&init_user_ns, qid)) +
201                 ((qid.type == USRQUOTA) ? 0 : 1);
202 }
203
204 static u64 qd2offset(struct gfs2_quota_data *qd)
205 {
206         u64 offset;
207
208         offset = qd2index(qd);
209         offset *= sizeof(struct gfs2_quota);
210
211         return offset;
212 }
213
214 static struct gfs2_quota_data *qd_alloc(unsigned hash, struct gfs2_sbd *sdp, struct kqid qid)
215 {
216         struct gfs2_quota_data *qd;
217         int error;
218
219         qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
220         if (!qd)
221                 return NULL;
222
223         qd->qd_sbd = sdp;
224         qd->qd_lockref.count = 1;
225         spin_lock_init(&qd->qd_lockref.lock);
226         qd->qd_id = qid;
227         qd->qd_slot = -1;
228         INIT_LIST_HEAD(&qd->qd_lru);
229         qd->qd_hash = hash;
230
231         error = gfs2_glock_get(sdp, qd2index(qd),
232                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
233         if (error)
234                 goto fail;
235
236         return qd;
237
238 fail:
239         kmem_cache_free(gfs2_quotad_cachep, qd);
240         return NULL;
241 }
242
243 static struct gfs2_quota_data *gfs2_qd_search_bucket(unsigned int hash,
244                                                      const struct gfs2_sbd *sdp,
245                                                      struct kqid qid)
246 {
247         struct gfs2_quota_data *qd;
248         struct hlist_bl_node *h;
249
250         hlist_bl_for_each_entry_rcu(qd, h, &qd_hash_table[hash], qd_hlist) {
251                 if (!qid_eq(qd->qd_id, qid))
252                         continue;
253                 if (qd->qd_sbd != sdp)
254                         continue;
255                 if (lockref_get_not_dead(&qd->qd_lockref)) {
256                         list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
257                         return qd;
258                 }
259         }
260
261         return NULL;
262 }
263
264
265 static int qd_get(struct gfs2_sbd *sdp, struct kqid qid,
266                   struct gfs2_quota_data **qdp)
267 {
268         struct gfs2_quota_data *qd, *new_qd;
269         unsigned int hash = gfs2_qd_hash(sdp, qid);
270
271         rcu_read_lock();
272         *qdp = qd = gfs2_qd_search_bucket(hash, sdp, qid);
273         rcu_read_unlock();
274
275         if (qd)
276                 return 0;
277
278         new_qd = qd_alloc(hash, sdp, qid);
279         if (!new_qd)
280                 return -ENOMEM;
281
282         spin_lock(&qd_lock);
283         spin_lock_bucket(hash);
284         *qdp = qd = gfs2_qd_search_bucket(hash, sdp, qid);
285         if (qd == NULL) {
286                 *qdp = new_qd;
287                 list_add(&new_qd->qd_list, &sdp->sd_quota_list);
288                 hlist_bl_add_head_rcu(&new_qd->qd_hlist, &qd_hash_table[hash]);
289                 atomic_inc(&sdp->sd_quota_count);
290         }
291         spin_unlock_bucket(hash);
292         spin_unlock(&qd_lock);
293
294         if (qd) {
295                 gfs2_glock_put(new_qd->qd_gl);
296                 kmem_cache_free(gfs2_quotad_cachep, new_qd);
297         }
298
299         return 0;
300 }
301
302
303 static void qd_hold(struct gfs2_quota_data *qd)
304 {
305         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
306         gfs2_assert(sdp, !__lockref_is_dead(&qd->qd_lockref));
307         lockref_get(&qd->qd_lockref);
308 }
309
310 static void qd_put(struct gfs2_quota_data *qd)
311 {
312         if (lockref_put_or_lock(&qd->qd_lockref))
313                 return;
314
315         qd->qd_lockref.count = 0;
316         list_lru_add(&gfs2_qd_lru, &qd->qd_lru);
317         spin_unlock(&qd->qd_lockref.lock);
318
319 }
320
321 static int slot_get(struct gfs2_quota_data *qd)
322 {
323         struct gfs2_sbd *sdp = qd->qd_sbd;
324         unsigned int bit;
325         int error = 0;
326
327         spin_lock(&sdp->sd_bitmap_lock);
328         if (qd->qd_slot_count != 0)
329                 goto out;
330
331         error = -ENOSPC;
332         bit = find_first_zero_bit(sdp->sd_quota_bitmap, sdp->sd_quota_slots);
333         if (bit < sdp->sd_quota_slots) {
334                 set_bit(bit, sdp->sd_quota_bitmap);
335                 qd->qd_slot = bit;
336                 error = 0;
337 out:
338                 qd->qd_slot_count++;
339         }
340         spin_unlock(&sdp->sd_bitmap_lock);
341
342         return error;
343 }
344
345 static void slot_hold(struct gfs2_quota_data *qd)
346 {
347         struct gfs2_sbd *sdp = qd->qd_sbd;
348
349         spin_lock(&sdp->sd_bitmap_lock);
350         gfs2_assert(sdp, qd->qd_slot_count);
351         qd->qd_slot_count++;
352         spin_unlock(&sdp->sd_bitmap_lock);
353 }
354
355 static void slot_put(struct gfs2_quota_data *qd)
356 {
357         struct gfs2_sbd *sdp = qd->qd_sbd;
358
359         spin_lock(&sdp->sd_bitmap_lock);
360         gfs2_assert(sdp, qd->qd_slot_count);
361         if (!--qd->qd_slot_count) {
362                 BUG_ON(!test_and_clear_bit(qd->qd_slot, sdp->sd_quota_bitmap));
363                 qd->qd_slot = -1;
364         }
365         spin_unlock(&sdp->sd_bitmap_lock);
366 }
367
368 static int bh_get(struct gfs2_quota_data *qd)
369 {
370         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
371         struct inode *inode = sdp->sd_qc_inode;
372         struct gfs2_inode *ip = GFS2_I(inode);
373         unsigned int block, offset;
374         struct buffer_head *bh;
375         struct iomap iomap = { };
376         int error;
377
378         mutex_lock(&sdp->sd_quota_mutex);
379
380         if (qd->qd_bh_count++) {
381                 mutex_unlock(&sdp->sd_quota_mutex);
382                 return 0;
383         }
384
385         block = qd->qd_slot / sdp->sd_qc_per_block;
386         offset = qd->qd_slot % sdp->sd_qc_per_block;
387
388         error = gfs2_iomap_get(inode,
389                                (loff_t)block << inode->i_blkbits,
390                                i_blocksize(inode), &iomap);
391         if (error)
392                 goto fail;
393         error = -ENOENT;
394         if (iomap.type != IOMAP_MAPPED)
395                 goto fail;
396
397         error = gfs2_meta_read(ip->i_gl, iomap.addr >> inode->i_blkbits,
398                                DIO_WAIT, 0, &bh);
399         if (error)
400                 goto fail;
401         error = -EIO;
402         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
403                 goto fail_brelse;
404
405         qd->qd_bh = bh;
406         qd->qd_bh_qc = (struct gfs2_quota_change *)
407                 (bh->b_data + sizeof(struct gfs2_meta_header) +
408                  offset * sizeof(struct gfs2_quota_change));
409
410         mutex_unlock(&sdp->sd_quota_mutex);
411
412         return 0;
413
414 fail_brelse:
415         brelse(bh);
416 fail:
417         qd->qd_bh_count--;
418         mutex_unlock(&sdp->sd_quota_mutex);
419         return error;
420 }
421
422 static void bh_put(struct gfs2_quota_data *qd)
423 {
424         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
425
426         mutex_lock(&sdp->sd_quota_mutex);
427         gfs2_assert(sdp, qd->qd_bh_count);
428         if (!--qd->qd_bh_count) {
429                 brelse(qd->qd_bh);
430                 qd->qd_bh = NULL;
431                 qd->qd_bh_qc = NULL;
432         }
433         mutex_unlock(&sdp->sd_quota_mutex);
434 }
435
436 static int qd_check_sync(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd,
437                          u64 *sync_gen)
438 {
439         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
440             !test_bit(QDF_CHANGE, &qd->qd_flags) ||
441             (sync_gen && (qd->qd_sync_gen >= *sync_gen)))
442                 return 0;
443
444         if (!lockref_get_not_dead(&qd->qd_lockref))
445                 return 0;
446
447         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
448         set_bit(QDF_LOCKED, &qd->qd_flags);
449         qd->qd_change_sync = qd->qd_change;
450         slot_hold(qd);
451         return 1;
452 }
453
454 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
455 {
456         struct gfs2_quota_data *qd = NULL, *iter;
457         int error;
458
459         *qdp = NULL;
460
461         if (sb_rdonly(sdp->sd_vfs))
462                 return 0;
463
464         spin_lock(&qd_lock);
465
466         list_for_each_entry(iter, &sdp->sd_quota_list, qd_list) {
467                 if (qd_check_sync(sdp, iter, &sdp->sd_quota_sync_gen)) {
468                         qd = iter;
469                         break;
470                 }
471         }
472
473         spin_unlock(&qd_lock);
474
475         if (qd) {
476                 error = bh_get(qd);
477                 if (error) {
478                         clear_bit(QDF_LOCKED, &qd->qd_flags);
479                         slot_put(qd);
480                         qd_put(qd);
481                         return error;
482                 }
483         }
484
485         *qdp = qd;
486
487         return 0;
488 }
489
490 static void qd_unlock(struct gfs2_quota_data *qd)
491 {
492         gfs2_assert_warn(qd->qd_gl->gl_name.ln_sbd,
493                          test_bit(QDF_LOCKED, &qd->qd_flags));
494         clear_bit(QDF_LOCKED, &qd->qd_flags);
495         bh_put(qd);
496         slot_put(qd);
497         qd_put(qd);
498 }
499
500 static int qdsb_get(struct gfs2_sbd *sdp, struct kqid qid,
501                     struct gfs2_quota_data **qdp)
502 {
503         int error;
504
505         error = qd_get(sdp, qid, qdp);
506         if (error)
507                 return error;
508
509         error = slot_get(*qdp);
510         if (error)
511                 goto fail;
512
513         error = bh_get(*qdp);
514         if (error)
515                 goto fail_slot;
516
517         return 0;
518
519 fail_slot:
520         slot_put(*qdp);
521 fail:
522         qd_put(*qdp);
523         return error;
524 }
525
526 static void qdsb_put(struct gfs2_quota_data *qd)
527 {
528         bh_put(qd);
529         slot_put(qd);
530         qd_put(qd);
531 }
532
533 /**
534  * gfs2_qa_get - make sure we have a quota allocations data structure,
535  *               if necessary
536  * @ip: the inode for this reservation
537  */
538 int gfs2_qa_get(struct gfs2_inode *ip)
539 {
540         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
541         struct inode *inode = &ip->i_inode;
542
543         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
544                 return 0;
545
546         spin_lock(&inode->i_lock);
547         if (ip->i_qadata == NULL) {
548                 struct gfs2_qadata *tmp;
549
550                 spin_unlock(&inode->i_lock);
551                 tmp = kmem_cache_zalloc(gfs2_qadata_cachep, GFP_NOFS);
552                 if (!tmp)
553                         return -ENOMEM;
554
555                 spin_lock(&inode->i_lock);
556                 if (ip->i_qadata == NULL)
557                         ip->i_qadata = tmp;
558                 else
559                         kmem_cache_free(gfs2_qadata_cachep, tmp);
560         }
561         ip->i_qadata->qa_ref++;
562         spin_unlock(&inode->i_lock);
563         return 0;
564 }
565
566 void gfs2_qa_put(struct gfs2_inode *ip)
567 {
568         struct inode *inode = &ip->i_inode;
569
570         spin_lock(&inode->i_lock);
571         if (ip->i_qadata && --ip->i_qadata->qa_ref == 0) {
572                 kmem_cache_free(gfs2_qadata_cachep, ip->i_qadata);
573                 ip->i_qadata = NULL;
574         }
575         spin_unlock(&inode->i_lock);
576 }
577
578 int gfs2_quota_hold(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
579 {
580         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
581         struct gfs2_quota_data **qd;
582         int error;
583
584         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
585                 return 0;
586
587         error = gfs2_qa_get(ip);
588         if (error)
589                 return error;
590
591         qd = ip->i_qadata->qa_qd;
592
593         if (gfs2_assert_warn(sdp, !ip->i_qadata->qa_qd_num) ||
594             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags))) {
595                 error = -EIO;
596                 gfs2_qa_put(ip);
597                 goto out;
598         }
599
600         error = qdsb_get(sdp, make_kqid_uid(ip->i_inode.i_uid), qd);
601         if (error)
602                 goto out_unhold;
603         ip->i_qadata->qa_qd_num++;
604         qd++;
605
606         error = qdsb_get(sdp, make_kqid_gid(ip->i_inode.i_gid), qd);
607         if (error)
608                 goto out_unhold;
609         ip->i_qadata->qa_qd_num++;
610         qd++;
611
612         if (!uid_eq(uid, NO_UID_QUOTA_CHANGE) &&
613             !uid_eq(uid, ip->i_inode.i_uid)) {
614                 error = qdsb_get(sdp, make_kqid_uid(uid), qd);
615                 if (error)
616                         goto out_unhold;
617                 ip->i_qadata->qa_qd_num++;
618                 qd++;
619         }
620
621         if (!gid_eq(gid, NO_GID_QUOTA_CHANGE) &&
622             !gid_eq(gid, ip->i_inode.i_gid)) {
623                 error = qdsb_get(sdp, make_kqid_gid(gid), qd);
624                 if (error)
625                         goto out_unhold;
626                 ip->i_qadata->qa_qd_num++;
627                 qd++;
628         }
629
630 out_unhold:
631         if (error)
632                 gfs2_quota_unhold(ip);
633 out:
634         return error;
635 }
636
637 void gfs2_quota_unhold(struct gfs2_inode *ip)
638 {
639         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
640         u32 x;
641
642         if (ip->i_qadata == NULL)
643                 return;
644
645         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
646
647         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
648                 qdsb_put(ip->i_qadata->qa_qd[x]);
649                 ip->i_qadata->qa_qd[x] = NULL;
650         }
651         ip->i_qadata->qa_qd_num = 0;
652         gfs2_qa_put(ip);
653 }
654
655 static int sort_qd(const void *a, const void *b)
656 {
657         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
658         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
659
660         if (qid_lt(qd_a->qd_id, qd_b->qd_id))
661                 return -1;
662         if (qid_lt(qd_b->qd_id, qd_a->qd_id))
663                 return 1;
664         return 0;
665 }
666
667 static void do_qc(struct gfs2_quota_data *qd, s64 change, int qc_type)
668 {
669         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
670         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
671         struct gfs2_quota_change *qc = qd->qd_bh_qc;
672         s64 x;
673
674         mutex_lock(&sdp->sd_quota_mutex);
675         gfs2_trans_add_meta(ip->i_gl, qd->qd_bh);
676
677         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
678                 qc->qc_change = 0;
679                 qc->qc_flags = 0;
680                 if (qd->qd_id.type == USRQUOTA)
681                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
682                 qc->qc_id = cpu_to_be32(from_kqid(&init_user_ns, qd->qd_id));
683         }
684
685         x = be64_to_cpu(qc->qc_change) + change;
686         qc->qc_change = cpu_to_be64(x);
687
688         spin_lock(&qd_lock);
689         qd->qd_change = x;
690         spin_unlock(&qd_lock);
691
692         if (qc_type == QC_CHANGE) {
693                 if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
694                         qd_hold(qd);
695                         slot_hold(qd);
696                 }
697         } else {
698                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
699                 clear_bit(QDF_CHANGE, &qd->qd_flags);
700                 qc->qc_flags = 0;
701                 qc->qc_id = 0;
702                 slot_put(qd);
703                 qd_put(qd);
704         }
705
706         if (change < 0) /* Reset quiet flag if we freed some blocks */
707                 clear_bit(QDF_QMSG_QUIET, &qd->qd_flags);
708         mutex_unlock(&sdp->sd_quota_mutex);
709 }
710
711 static int gfs2_write_buf_to_page(struct gfs2_inode *ip, unsigned long index,
712                                   unsigned off, void *buf, unsigned bytes)
713 {
714         struct inode *inode = &ip->i_inode;
715         struct gfs2_sbd *sdp = GFS2_SB(inode);
716         struct address_space *mapping = inode->i_mapping;
717         struct page *page;
718         struct buffer_head *bh;
719         u64 blk;
720         unsigned bsize = sdp->sd_sb.sb_bsize, bnum = 0, boff = 0;
721         unsigned to_write = bytes, pg_off = off;
722         int done = 0;
723
724         blk = index << (PAGE_SHIFT - sdp->sd_sb.sb_bsize_shift);
725         boff = off % bsize;
726
727         page = find_or_create_page(mapping, index, GFP_NOFS);
728         if (!page)
729                 return -ENOMEM;
730         if (!page_has_buffers(page))
731                 create_empty_buffers(page, bsize, 0);
732
733         bh = page_buffers(page);
734         while (!done) {
735                 /* Find the beginning block within the page */
736                 if (pg_off >= ((bnum * bsize) + bsize)) {
737                         bh = bh->b_this_page;
738                         bnum++;
739                         blk++;
740                         continue;
741                 }
742                 if (!buffer_mapped(bh)) {
743                         gfs2_block_map(inode, blk, bh, 1);
744                         if (!buffer_mapped(bh))
745                                 goto unlock_out;
746                         /* If it's a newly allocated disk block, zero it */
747                         if (buffer_new(bh))
748                                 zero_user(page, bnum * bsize, bh->b_size);
749                 }
750                 if (PageUptodate(page))
751                         set_buffer_uptodate(bh);
752                 if (bh_read(bh, REQ_META | REQ_PRIO) < 0)
753                         goto unlock_out;
754                 if (gfs2_is_jdata(ip))
755                         gfs2_trans_add_data(ip->i_gl, bh);
756                 else
757                         gfs2_ordered_add_inode(ip);
758
759                 /* If we need to write to the next block as well */
760                 if (to_write > (bsize - boff)) {
761                         pg_off += (bsize - boff);
762                         to_write -= (bsize - boff);
763                         boff = pg_off % bsize;
764                         continue;
765                 }
766                 done = 1;
767         }
768
769         /* Write to the page, now that we have setup the buffer(s) */
770         memcpy_to_page(page, off, buf, bytes);
771         flush_dcache_page(page);
772         unlock_page(page);
773         put_page(page);
774
775         return 0;
776
777 unlock_out:
778         unlock_page(page);
779         put_page(page);
780         return -EIO;
781 }
782
783 static int gfs2_write_disk_quota(struct gfs2_inode *ip, struct gfs2_quota *qp,
784                                  loff_t loc)
785 {
786         unsigned long pg_beg;
787         unsigned pg_off, nbytes, overflow = 0;
788         int pg_oflow = 0, error;
789         void *ptr;
790
791         nbytes = sizeof(struct gfs2_quota);
792
793         pg_beg = loc >> PAGE_SHIFT;
794         pg_off = offset_in_page(loc);
795
796         /* If the quota straddles a page boundary, split the write in two */
797         if ((pg_off + nbytes) > PAGE_SIZE) {
798                 pg_oflow = 1;
799                 overflow = (pg_off + nbytes) - PAGE_SIZE;
800         }
801
802         ptr = qp;
803         error = gfs2_write_buf_to_page(ip, pg_beg, pg_off, ptr,
804                                        nbytes - overflow);
805         /* If there's an overflow, write the remaining bytes to the next page */
806         if (!error && pg_oflow)
807                 error = gfs2_write_buf_to_page(ip, pg_beg + 1, 0,
808                                                ptr + nbytes - overflow,
809                                                overflow);
810         return error;
811 }
812
813 /**
814  * gfs2_adjust_quota - adjust record of current block usage
815  * @ip: The quota inode
816  * @loc: Offset of the entry in the quota file
817  * @change: The amount of usage change to record
818  * @qd: The quota data
819  * @fdq: The updated limits to record
820  *
821  * This function was mostly borrowed from gfs2_block_truncate_page which was
822  * in turn mostly borrowed from ext3
823  *
824  * Returns: 0 or -ve on error
825  */
826
827 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
828                              s64 change, struct gfs2_quota_data *qd,
829                              struct qc_dqblk *fdq)
830 {
831         struct inode *inode = &ip->i_inode;
832         struct gfs2_sbd *sdp = GFS2_SB(inode);
833         struct gfs2_quota q;
834         int err;
835         u64 size;
836
837         if (gfs2_is_stuffed(ip)) {
838                 err = gfs2_unstuff_dinode(ip);
839                 if (err)
840                         return err;
841         }
842
843         memset(&q, 0, sizeof(struct gfs2_quota));
844         err = gfs2_internal_read(ip, (char *)&q, &loc, sizeof(q));
845         if (err < 0)
846                 return err;
847
848         loc -= sizeof(q); /* gfs2_internal_read would've advanced the loc ptr */
849         err = -EIO;
850         be64_add_cpu(&q.qu_value, change);
851         if (((s64)be64_to_cpu(q.qu_value)) < 0)
852                 q.qu_value = 0; /* Never go negative on quota usage */
853         qd->qd_qb.qb_value = q.qu_value;
854         if (fdq) {
855                 if (fdq->d_fieldmask & QC_SPC_SOFT) {
856                         q.qu_warn = cpu_to_be64(fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift);
857                         qd->qd_qb.qb_warn = q.qu_warn;
858                 }
859                 if (fdq->d_fieldmask & QC_SPC_HARD) {
860                         q.qu_limit = cpu_to_be64(fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift);
861                         qd->qd_qb.qb_limit = q.qu_limit;
862                 }
863                 if (fdq->d_fieldmask & QC_SPACE) {
864                         q.qu_value = cpu_to_be64(fdq->d_space >> sdp->sd_sb.sb_bsize_shift);
865                         qd->qd_qb.qb_value = q.qu_value;
866                 }
867         }
868
869         err = gfs2_write_disk_quota(ip, &q, loc);
870         if (!err) {
871                 size = loc + sizeof(struct gfs2_quota);
872                 if (size > inode->i_size)
873                         i_size_write(inode, size);
874                 inode->i_mtime = inode_set_ctime_current(inode);
875                 mark_inode_dirty(inode);
876                 set_bit(QDF_REFRESH, &qd->qd_flags);
877         }
878
879         return err;
880 }
881
882 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
883 {
884         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_name.ln_sbd;
885         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
886         struct gfs2_alloc_parms ap = { .aflags = 0, };
887         unsigned int data_blocks, ind_blocks;
888         struct gfs2_holder *ghs, i_gh;
889         unsigned int qx, x;
890         struct gfs2_quota_data *qd;
891         unsigned reserved;
892         loff_t offset;
893         unsigned int nalloc = 0, blocks;
894         int error;
895
896         error = gfs2_qa_get(ip);
897         if (error)
898                 return error;
899
900         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
901                               &data_blocks, &ind_blocks);
902
903         ghs = kmalloc_array(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
904         if (!ghs) {
905                 error = -ENOMEM;
906                 goto out;
907         }
908
909         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
910         inode_lock(&ip->i_inode);
911         for (qx = 0; qx < num_qd; qx++) {
912                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
913                                            GL_NOCACHE, &ghs[qx]);
914                 if (error)
915                         goto out_dq;
916         }
917
918         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
919         if (error)
920                 goto out_dq;
921
922         for (x = 0; x < num_qd; x++) {
923                 offset = qd2offset(qda[x]);
924                 if (gfs2_write_alloc_required(ip, offset,
925                                               sizeof(struct gfs2_quota)))
926                         nalloc++;
927         }
928
929         /* 
930          * 1 blk for unstuffing inode if stuffed. We add this extra
931          * block to the reservation unconditionally. If the inode
932          * doesn't need unstuffing, the block will be released to the 
933          * rgrp since it won't be allocated during the transaction
934          */
935         /* +3 in the end for unstuffing block, inode size update block
936          * and another block in case quota straddles page boundary and 
937          * two blocks need to be updated instead of 1 */
938         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
939
940         reserved = 1 + (nalloc * (data_blocks + ind_blocks));
941         ap.target = reserved;
942         error = gfs2_inplace_reserve(ip, &ap);
943         if (error)
944                 goto out_alloc;
945
946         if (nalloc)
947                 blocks += gfs2_rg_blocks(ip, reserved) + nalloc * ind_blocks + RES_STATFS;
948
949         error = gfs2_trans_begin(sdp, blocks, 0);
950         if (error)
951                 goto out_ipres;
952
953         for (x = 0; x < num_qd; x++) {
954                 qd = qda[x];
955                 offset = qd2offset(qd);
956                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
957                 if (error)
958                         goto out_end_trans;
959
960                 do_qc(qd, -qd->qd_change_sync, QC_SYNC);
961                 set_bit(QDF_REFRESH, &qd->qd_flags);
962         }
963
964         error = 0;
965
966 out_end_trans:
967         gfs2_trans_end(sdp);
968 out_ipres:
969         gfs2_inplace_release(ip);
970 out_alloc:
971         gfs2_glock_dq_uninit(&i_gh);
972 out_dq:
973         while (qx--)
974                 gfs2_glock_dq_uninit(&ghs[qx]);
975         inode_unlock(&ip->i_inode);
976         kfree(ghs);
977         gfs2_log_flush(ip->i_gl->gl_name.ln_sbd, ip->i_gl,
978                        GFS2_LOG_HEAD_FLUSH_NORMAL | GFS2_LFC_DO_SYNC);
979 out:
980         gfs2_qa_put(ip);
981         return error;
982 }
983
984 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
985 {
986         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
987         struct gfs2_quota q;
988         struct gfs2_quota_lvb *qlvb;
989         loff_t pos;
990         int error;
991
992         memset(&q, 0, sizeof(struct gfs2_quota));
993         pos = qd2offset(qd);
994         error = gfs2_internal_read(ip, (char *)&q, &pos, sizeof(q));
995         if (error < 0)
996                 return error;
997
998         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
999         qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
1000         qlvb->__pad = 0;
1001         qlvb->qb_limit = q.qu_limit;
1002         qlvb->qb_warn = q.qu_warn;
1003         qlvb->qb_value = q.qu_value;
1004         qd->qd_qb = *qlvb;
1005
1006         return 0;
1007 }
1008
1009 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
1010                     struct gfs2_holder *q_gh)
1011 {
1012         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1013         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1014         struct gfs2_holder i_gh;
1015         int error;
1016
1017 restart:
1018         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
1019         if (error)
1020                 return error;
1021
1022         if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
1023                 force_refresh = FORCE;
1024
1025         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1026
1027         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
1028                 gfs2_glock_dq_uninit(q_gh);
1029                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
1030                                            GL_NOCACHE, q_gh);
1031                 if (error)
1032                         return error;
1033
1034                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
1035                 if (error)
1036                         goto fail;
1037
1038                 error = update_qd(sdp, qd);
1039                 if (error)
1040                         goto fail_gunlock;
1041
1042                 gfs2_glock_dq_uninit(&i_gh);
1043                 gfs2_glock_dq_uninit(q_gh);
1044                 force_refresh = 0;
1045                 goto restart;
1046         }
1047
1048         return 0;
1049
1050 fail_gunlock:
1051         gfs2_glock_dq_uninit(&i_gh);
1052 fail:
1053         gfs2_glock_dq_uninit(q_gh);
1054         return error;
1055 }
1056
1057 int gfs2_quota_lock(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
1058 {
1059         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1060         struct gfs2_quota_data *qd;
1061         u32 x;
1062         int error = 0;
1063
1064         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1065                 return 0;
1066
1067         error = gfs2_quota_hold(ip, uid, gid);
1068         if (error)
1069                 return error;
1070
1071         sort(ip->i_qadata->qa_qd, ip->i_qadata->qa_qd_num,
1072              sizeof(struct gfs2_quota_data *), sort_qd, NULL);
1073
1074         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1075                 qd = ip->i_qadata->qa_qd[x];
1076                 error = do_glock(qd, NO_FORCE, &ip->i_qadata->qa_qd_ghs[x]);
1077                 if (error)
1078                         break;
1079         }
1080
1081         if (!error)
1082                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
1083         else {
1084                 while (x--)
1085                         gfs2_glock_dq_uninit(&ip->i_qadata->qa_qd_ghs[x]);
1086                 gfs2_quota_unhold(ip);
1087         }
1088
1089         return error;
1090 }
1091
1092 static int need_sync(struct gfs2_quota_data *qd)
1093 {
1094         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1095         struct gfs2_tune *gt = &sdp->sd_tune;
1096         s64 value;
1097         unsigned int num, den;
1098         int do_sync = 1;
1099
1100         if (!qd->qd_qb.qb_limit)
1101                 return 0;
1102
1103         spin_lock(&qd_lock);
1104         value = qd->qd_change;
1105         spin_unlock(&qd_lock);
1106
1107         spin_lock(&gt->gt_spin);
1108         num = gt->gt_quota_scale_num;
1109         den = gt->gt_quota_scale_den;
1110         spin_unlock(&gt->gt_spin);
1111
1112         if (value < 0)
1113                 do_sync = 0;
1114         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
1115                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1116                 do_sync = 0;
1117         else {
1118                 value *= gfs2_jindex_size(sdp) * num;
1119                 value = div_s64(value, den);
1120                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
1121                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1122                         do_sync = 0;
1123         }
1124
1125         return do_sync;
1126 }
1127
1128 void gfs2_quota_unlock(struct gfs2_inode *ip)
1129 {
1130         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1131         struct gfs2_quota_data *qda[4];
1132         unsigned int count = 0;
1133         u32 x;
1134         int found;
1135
1136         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1137                 return;
1138
1139         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1140                 struct gfs2_quota_data *qd;
1141                 int sync;
1142
1143                 qd = ip->i_qadata->qa_qd[x];
1144                 sync = need_sync(qd);
1145
1146                 gfs2_glock_dq_uninit(&ip->i_qadata->qa_qd_ghs[x]);
1147                 if (!sync)
1148                         continue;
1149
1150                 spin_lock(&qd_lock);
1151                 found = qd_check_sync(sdp, qd, NULL);
1152                 spin_unlock(&qd_lock);
1153
1154                 if (!found)
1155                         continue;
1156
1157                 gfs2_assert_warn(sdp, qd->qd_change_sync);
1158                 if (bh_get(qd)) {
1159                         clear_bit(QDF_LOCKED, &qd->qd_flags);
1160                         slot_put(qd);
1161                         qd_put(qd);
1162                         continue;
1163                 }
1164
1165                 qda[count++] = qd;
1166         }
1167
1168         if (count) {
1169                 do_sync(count, qda);
1170                 for (x = 0; x < count; x++)
1171                         qd_unlock(qda[x]);
1172         }
1173
1174         gfs2_quota_unhold(ip);
1175 }
1176
1177 #define MAX_LINE 256
1178
1179 static int print_message(struct gfs2_quota_data *qd, char *type)
1180 {
1181         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1182
1183         fs_info(sdp, "quota %s for %s %u\n",
1184                 type,
1185                 (qd->qd_id.type == USRQUOTA) ? "user" : "group",
1186                 from_kqid(&init_user_ns, qd->qd_id));
1187
1188         return 0;
1189 }
1190
1191 /**
1192  * gfs2_quota_check - check if allocating new blocks will exceed quota
1193  * @ip:  The inode for which this check is being performed
1194  * @uid: The uid to check against
1195  * @gid: The gid to check against
1196  * @ap:  The allocation parameters. ap->target contains the requested
1197  *       blocks. ap->min_target, if set, contains the minimum blks
1198  *       requested.
1199  *
1200  * Returns: 0 on success.
1201  *                  min_req = ap->min_target ? ap->min_target : ap->target;
1202  *                  quota must allow at least min_req blks for success and
1203  *                  ap->allowed is set to the number of blocks allowed
1204  *
1205  *          -EDQUOT otherwise, quota violation. ap->allowed is set to number
1206  *                  of blocks available.
1207  */
1208 int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid,
1209                      struct gfs2_alloc_parms *ap)
1210 {
1211         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1212         struct gfs2_quota_data *qd;
1213         s64 value, warn, limit;
1214         u32 x;
1215         int error = 0;
1216
1217         ap->allowed = UINT_MAX; /* Assume we are permitted a whole lot */
1218         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1219                 return 0;
1220
1221         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1222                 qd = ip->i_qadata->qa_qd[x];
1223
1224                 if (!(qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1225                       qid_eq(qd->qd_id, make_kqid_gid(gid))))
1226                         continue;
1227
1228                 warn = (s64)be64_to_cpu(qd->qd_qb.qb_warn);
1229                 limit = (s64)be64_to_cpu(qd->qd_qb.qb_limit);
1230                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1231                 spin_lock(&qd_lock);
1232                 value += qd->qd_change;
1233                 spin_unlock(&qd_lock);
1234
1235                 if (limit > 0 && (limit - value) < ap->allowed)
1236                         ap->allowed = limit - value;
1237                 /* If we can't meet the target */
1238                 if (limit && limit < (value + (s64)ap->target)) {
1239                         /* If no min_target specified or we don't meet
1240                          * min_target, return -EDQUOT */
1241                         if (!ap->min_target || ap->min_target > ap->allowed) {
1242                                 if (!test_and_set_bit(QDF_QMSG_QUIET,
1243                                                       &qd->qd_flags)) {
1244                                         print_message(qd, "exceeded");
1245                                         quota_send_warning(qd->qd_id,
1246                                                            sdp->sd_vfs->s_dev,
1247                                                            QUOTA_NL_BHARDWARN);
1248                                 }
1249                                 error = -EDQUOT;
1250                                 break;
1251                         }
1252                 } else if (warn && warn < value &&
1253                            time_after_eq(jiffies, qd->qd_last_warn +
1254                                          gfs2_tune_get(sdp, gt_quota_warn_period)
1255                                          * HZ)) {
1256                         quota_send_warning(qd->qd_id,
1257                                            sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1258                         error = print_message(qd, "warning");
1259                         qd->qd_last_warn = jiffies;
1260                 }
1261         }
1262         return error;
1263 }
1264
1265 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1266                        kuid_t uid, kgid_t gid)
1267 {
1268         struct gfs2_quota_data *qd;
1269         u32 x;
1270         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1271
1272         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON ||
1273             gfs2_assert_warn(sdp, change))
1274                 return;
1275         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1276                 return;
1277
1278         if (gfs2_assert_withdraw(sdp, ip->i_qadata &&
1279                                  ip->i_qadata->qa_ref > 0))
1280                 return;
1281         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1282                 qd = ip->i_qadata->qa_qd[x];
1283
1284                 if (qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1285                     qid_eq(qd->qd_id, make_kqid_gid(gid))) {
1286                         do_qc(qd, change, QC_CHANGE);
1287                 }
1288         }
1289 }
1290
1291 int gfs2_quota_sync(struct super_block *sb, int type)
1292 {
1293         struct gfs2_sbd *sdp = sb->s_fs_info;
1294         struct gfs2_quota_data **qda;
1295         unsigned int max_qd = PAGE_SIZE / sizeof(struct gfs2_holder);
1296         unsigned int num_qd;
1297         unsigned int x;
1298         int error = 0;
1299
1300         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1301         if (!qda)
1302                 return -ENOMEM;
1303
1304         mutex_lock(&sdp->sd_quota_sync_mutex);
1305         sdp->sd_quota_sync_gen++;
1306
1307         do {
1308                 num_qd = 0;
1309
1310                 for (;;) {
1311                         error = qd_fish(sdp, qda + num_qd);
1312                         if (error || !qda[num_qd])
1313                                 break;
1314                         if (++num_qd == max_qd)
1315                                 break;
1316                 }
1317
1318                 if (num_qd) {
1319                         if (!error)
1320                                 error = do_sync(num_qd, qda);
1321                         if (!error)
1322                                 for (x = 0; x < num_qd; x++)
1323                                         qda[x]->qd_sync_gen =
1324                                                 sdp->sd_quota_sync_gen;
1325
1326                         for (x = 0; x < num_qd; x++)
1327                                 qd_unlock(qda[x]);
1328                 }
1329         } while (!error && num_qd == max_qd);
1330
1331         mutex_unlock(&sdp->sd_quota_sync_mutex);
1332         kfree(qda);
1333
1334         return error;
1335 }
1336
1337 int gfs2_quota_refresh(struct gfs2_sbd *sdp, struct kqid qid)
1338 {
1339         struct gfs2_quota_data *qd;
1340         struct gfs2_holder q_gh;
1341         int error;
1342
1343         error = qd_get(sdp, qid, &qd);
1344         if (error)
1345                 return error;
1346
1347         error = do_glock(qd, FORCE, &q_gh);
1348         if (!error)
1349                 gfs2_glock_dq_uninit(&q_gh);
1350
1351         qd_put(qd);
1352         return error;
1353 }
1354
1355 int gfs2_quota_init(struct gfs2_sbd *sdp)
1356 {
1357         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1358         u64 size = i_size_read(sdp->sd_qc_inode);
1359         unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1360         unsigned int x, slot = 0;
1361         unsigned int found = 0;
1362         unsigned int hash;
1363         unsigned int bm_size;
1364         u64 dblock;
1365         u32 extlen = 0;
1366         int error;
1367
1368         if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1369                 return -EIO;
1370
1371         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1372         bm_size = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * sizeof(unsigned long));
1373         bm_size *= sizeof(unsigned long);
1374         error = -ENOMEM;
1375         sdp->sd_quota_bitmap = kzalloc(bm_size, GFP_NOFS | __GFP_NOWARN);
1376         if (sdp->sd_quota_bitmap == NULL)
1377                 sdp->sd_quota_bitmap = __vmalloc(bm_size, GFP_NOFS |
1378                                                  __GFP_ZERO);
1379         if (!sdp->sd_quota_bitmap)
1380                 return error;
1381
1382         for (x = 0; x < blocks; x++) {
1383                 struct buffer_head *bh;
1384                 const struct gfs2_quota_change *qc;
1385                 unsigned int y;
1386
1387                 if (!extlen) {
1388                         extlen = 32;
1389                         error = gfs2_get_extent(&ip->i_inode, x, &dblock, &extlen);
1390                         if (error)
1391                                 goto fail;
1392                 }
1393                 error = -EIO;
1394                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1395                 if (!bh)
1396                         goto fail;
1397                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1398                         brelse(bh);
1399                         goto fail;
1400                 }
1401
1402                 qc = (const struct gfs2_quota_change *)(bh->b_data + sizeof(struct gfs2_meta_header));
1403                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1404                      y++, slot++) {
1405                         struct gfs2_quota_data *qd;
1406                         s64 qc_change = be64_to_cpu(qc->qc_change);
1407                         u32 qc_flags = be32_to_cpu(qc->qc_flags);
1408                         enum quota_type qtype = (qc_flags & GFS2_QCF_USER) ?
1409                                                 USRQUOTA : GRPQUOTA;
1410                         struct kqid qc_id = make_kqid(&init_user_ns, qtype,
1411                                                       be32_to_cpu(qc->qc_id));
1412                         qc++;
1413                         if (!qc_change)
1414                                 continue;
1415
1416                         hash = gfs2_qd_hash(sdp, qc_id);
1417                         qd = qd_alloc(hash, sdp, qc_id);
1418                         if (qd == NULL) {
1419                                 brelse(bh);
1420                                 goto fail;
1421                         }
1422
1423                         set_bit(QDF_CHANGE, &qd->qd_flags);
1424                         qd->qd_change = qc_change;
1425                         qd->qd_slot = slot;
1426                         qd->qd_slot_count = 1;
1427
1428                         spin_lock(&qd_lock);
1429                         BUG_ON(test_and_set_bit(slot, sdp->sd_quota_bitmap));
1430                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1431                         atomic_inc(&sdp->sd_quota_count);
1432                         spin_unlock(&qd_lock);
1433
1434                         spin_lock_bucket(hash);
1435                         hlist_bl_add_head_rcu(&qd->qd_hlist, &qd_hash_table[hash]);
1436                         spin_unlock_bucket(hash);
1437
1438                         found++;
1439                 }
1440
1441                 brelse(bh);
1442                 dblock++;
1443                 extlen--;
1444         }
1445
1446         if (found)
1447                 fs_info(sdp, "found %u quota changes\n", found);
1448
1449         return 0;
1450
1451 fail:
1452         gfs2_quota_cleanup(sdp);
1453         return error;
1454 }
1455
1456 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1457 {
1458         struct list_head *head = &sdp->sd_quota_list;
1459         struct gfs2_quota_data *qd;
1460
1461         spin_lock(&qd_lock);
1462         while (!list_empty(head)) {
1463                 qd = list_last_entry(head, struct gfs2_quota_data, qd_list);
1464
1465                 list_del(&qd->qd_list);
1466
1467                 /* Also remove if this qd exists in the reclaim list */
1468                 list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
1469                 atomic_dec(&sdp->sd_quota_count);
1470                 spin_unlock(&qd_lock);
1471
1472                 spin_lock_bucket(qd->qd_hash);
1473                 hlist_bl_del_rcu(&qd->qd_hlist);
1474                 spin_unlock_bucket(qd->qd_hash);
1475
1476                 gfs2_assert_warn(sdp, !qd->qd_change);
1477                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1478                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1479
1480                 gfs2_glock_put(qd->qd_gl);
1481                 call_rcu(&qd->qd_rcu, gfs2_qd_dealloc);
1482
1483                 spin_lock(&qd_lock);
1484         }
1485         spin_unlock(&qd_lock);
1486
1487         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1488
1489         kvfree(sdp->sd_quota_bitmap);
1490         sdp->sd_quota_bitmap = NULL;
1491 }
1492
1493 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1494 {
1495         if (error == 0 || error == -EROFS)
1496                 return;
1497         if (!gfs2_withdrawn(sdp)) {
1498                 if (!cmpxchg(&sdp->sd_log_error, 0, error))
1499                         fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1500                 wake_up(&sdp->sd_logd_waitq);
1501         }
1502 }
1503
1504 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1505                                int (*fxn)(struct super_block *sb, int type),
1506                                unsigned long t, unsigned long *timeo,
1507                                unsigned int *new_timeo)
1508 {
1509         if (t >= *timeo) {
1510                 int error = fxn(sdp->sd_vfs, 0);
1511                 quotad_error(sdp, msg, error);
1512                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1513         } else {
1514                 *timeo -= t;
1515         }
1516 }
1517
1518 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1519         if (!sdp->sd_statfs_force_sync) {
1520                 sdp->sd_statfs_force_sync = 1;
1521                 wake_up(&sdp->sd_quota_wait);
1522         }
1523 }
1524
1525
1526 /**
1527  * gfs2_quotad - Write cached quota changes into the quota file
1528  * @data: Pointer to GFS2 superblock
1529  *
1530  */
1531
1532 int gfs2_quotad(void *data)
1533 {
1534         struct gfs2_sbd *sdp = data;
1535         struct gfs2_tune *tune = &sdp->sd_tune;
1536         unsigned long statfs_timeo = 0;
1537         unsigned long quotad_timeo = 0;
1538         unsigned long t = 0;
1539         DEFINE_WAIT(wait);
1540
1541         while (!kthread_should_stop()) {
1542
1543                 if (gfs2_withdrawn(sdp))
1544                         goto bypass;
1545                 /* Update the master statfs file */
1546                 if (sdp->sd_statfs_force_sync) {
1547                         int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1548                         quotad_error(sdp, "statfs", error);
1549                         statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1550                 }
1551                 else
1552                         quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1553                                            &statfs_timeo,
1554                                            &tune->gt_statfs_quantum);
1555
1556                 /* Update quota file */
1557                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
1558                                    &quotad_timeo, &tune->gt_quota_quantum);
1559
1560                 try_to_freeze();
1561
1562 bypass:
1563                 t = min(quotad_timeo, statfs_timeo);
1564
1565                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1566                 if (!sdp->sd_statfs_force_sync)
1567                         t -= schedule_timeout(t);
1568                 else
1569                         t = 0;
1570                 finish_wait(&sdp->sd_quota_wait, &wait);
1571         }
1572
1573         return 0;
1574 }
1575
1576 static int gfs2_quota_get_state(struct super_block *sb, struct qc_state *state)
1577 {
1578         struct gfs2_sbd *sdp = sb->s_fs_info;
1579
1580         memset(state, 0, sizeof(*state));
1581
1582         switch (sdp->sd_args.ar_quota) {
1583         case GFS2_QUOTA_ON:
1584                 state->s_state[USRQUOTA].flags |= QCI_LIMITS_ENFORCED;
1585                 state->s_state[GRPQUOTA].flags |= QCI_LIMITS_ENFORCED;
1586                 fallthrough;
1587         case GFS2_QUOTA_ACCOUNT:
1588                 state->s_state[USRQUOTA].flags |= QCI_ACCT_ENABLED |
1589                                                   QCI_SYSFILE;
1590                 state->s_state[GRPQUOTA].flags |= QCI_ACCT_ENABLED |
1591                                                   QCI_SYSFILE;
1592                 break;
1593         case GFS2_QUOTA_OFF:
1594                 break;
1595         }
1596         if (sdp->sd_quota_inode) {
1597                 state->s_state[USRQUOTA].ino =
1598                                         GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1599                 state->s_state[USRQUOTA].blocks = sdp->sd_quota_inode->i_blocks;
1600         }
1601         state->s_state[USRQUOTA].nextents = 1;  /* unsupported */
1602         state->s_state[GRPQUOTA] = state->s_state[USRQUOTA];
1603         state->s_incoredqs = list_lru_count(&gfs2_qd_lru);
1604         return 0;
1605 }
1606
1607 static int gfs2_get_dqblk(struct super_block *sb, struct kqid qid,
1608                           struct qc_dqblk *fdq)
1609 {
1610         struct gfs2_sbd *sdp = sb->s_fs_info;
1611         struct gfs2_quota_lvb *qlvb;
1612         struct gfs2_quota_data *qd;
1613         struct gfs2_holder q_gh;
1614         int error;
1615
1616         memset(fdq, 0, sizeof(*fdq));
1617
1618         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1619                 return -ESRCH; /* Crazy XFS error code */
1620
1621         if ((qid.type != USRQUOTA) &&
1622             (qid.type != GRPQUOTA))
1623                 return -EINVAL;
1624
1625         error = qd_get(sdp, qid, &qd);
1626         if (error)
1627                 return error;
1628         error = do_glock(qd, FORCE, &q_gh);
1629         if (error)
1630                 goto out;
1631
1632         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1633         fdq->d_spc_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_sb.sb_bsize_shift;
1634         fdq->d_spc_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_sb.sb_bsize_shift;
1635         fdq->d_space = be64_to_cpu(qlvb->qb_value) << sdp->sd_sb.sb_bsize_shift;
1636
1637         gfs2_glock_dq_uninit(&q_gh);
1638 out:
1639         qd_put(qd);
1640         return error;
1641 }
1642
1643 /* GFS2 only supports a subset of the XFS fields */
1644 #define GFS2_FIELDMASK (QC_SPC_SOFT|QC_SPC_HARD|QC_SPACE)
1645
1646 static int gfs2_set_dqblk(struct super_block *sb, struct kqid qid,
1647                           struct qc_dqblk *fdq)
1648 {
1649         struct gfs2_sbd *sdp = sb->s_fs_info;
1650         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1651         struct gfs2_quota_data *qd;
1652         struct gfs2_holder q_gh, i_gh;
1653         unsigned int data_blocks, ind_blocks;
1654         unsigned int blocks = 0;
1655         int alloc_required;
1656         loff_t offset;
1657         int error;
1658
1659         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1660                 return -ESRCH; /* Crazy XFS error code */
1661
1662         if ((qid.type != USRQUOTA) &&
1663             (qid.type != GRPQUOTA))
1664                 return -EINVAL;
1665
1666         if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1667                 return -EINVAL;
1668
1669         error = qd_get(sdp, qid, &qd);
1670         if (error)
1671                 return error;
1672
1673         error = gfs2_qa_get(ip);
1674         if (error)
1675                 goto out_put;
1676
1677         inode_lock(&ip->i_inode);
1678         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1679         if (error)
1680                 goto out_unlockput;
1681         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1682         if (error)
1683                 goto out_q;
1684
1685         /* Check for existing entry, if none then alloc new blocks */
1686         error = update_qd(sdp, qd);
1687         if (error)
1688                 goto out_i;
1689
1690         /* If nothing has changed, this is a no-op */
1691         if ((fdq->d_fieldmask & QC_SPC_SOFT) &&
1692             ((fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1693                 fdq->d_fieldmask ^= QC_SPC_SOFT;
1694
1695         if ((fdq->d_fieldmask & QC_SPC_HARD) &&
1696             ((fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1697                 fdq->d_fieldmask ^= QC_SPC_HARD;
1698
1699         if ((fdq->d_fieldmask & QC_SPACE) &&
1700             ((fdq->d_space >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1701                 fdq->d_fieldmask ^= QC_SPACE;
1702
1703         if (fdq->d_fieldmask == 0)
1704                 goto out_i;
1705
1706         offset = qd2offset(qd);
1707         alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1708         if (gfs2_is_stuffed(ip))
1709                 alloc_required = 1;
1710         if (alloc_required) {
1711                 struct gfs2_alloc_parms ap = { .aflags = 0, };
1712                 gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1713                                        &data_blocks, &ind_blocks);
1714                 blocks = 1 + data_blocks + ind_blocks;
1715                 ap.target = blocks;
1716                 error = gfs2_inplace_reserve(ip, &ap);
1717                 if (error)
1718                         goto out_i;
1719                 blocks += gfs2_rg_blocks(ip, blocks);
1720         }
1721
1722         /* Some quotas span block boundaries and can update two blocks,
1723            adding an extra block to the transaction to handle such quotas */
1724         error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1725         if (error)
1726                 goto out_release;
1727
1728         /* Apply changes */
1729         error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1730         if (!error)
1731                 clear_bit(QDF_QMSG_QUIET, &qd->qd_flags);
1732
1733         gfs2_trans_end(sdp);
1734 out_release:
1735         if (alloc_required)
1736                 gfs2_inplace_release(ip);
1737 out_i:
1738         gfs2_glock_dq_uninit(&i_gh);
1739 out_q:
1740         gfs2_glock_dq_uninit(&q_gh);
1741 out_unlockput:
1742         gfs2_qa_put(ip);
1743         inode_unlock(&ip->i_inode);
1744 out_put:
1745         qd_put(qd);
1746         return error;
1747 }
1748
1749 const struct quotactl_ops gfs2_quotactl_ops = {
1750         .quota_sync     = gfs2_quota_sync,
1751         .get_state      = gfs2_quota_get_state,
1752         .get_dqblk      = gfs2_get_dqblk,
1753         .set_dqblk      = gfs2_set_dqblk,
1754 };
1755
1756 void __init gfs2_quota_hash_init(void)
1757 {
1758         unsigned i;
1759
1760         for(i = 0; i < GFS2_QD_HASH_SIZE; i++)
1761                 INIT_HLIST_BL_HEAD(&qd_hash_table[i]);
1762 }