RISC-V: Fix a race condition during kernel stack overflow
[platform/kernel/linux-starfive.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 /* Lock order: qd_lock -> bucket lock -> qd->lockref.lock -> lru lock */
79 /*                     -> sd_bitmap_lock                              */
80 static DEFINE_SPINLOCK(qd_lock);
81 struct list_lru gfs2_qd_lru;
82
83 static struct hlist_bl_head qd_hash_table[GFS2_QD_HASH_SIZE];
84
85 static unsigned int gfs2_qd_hash(const struct gfs2_sbd *sdp,
86                                  const struct kqid qid)
87 {
88         unsigned int h;
89
90         h = jhash(&sdp, sizeof(struct gfs2_sbd *), 0);
91         h = jhash(&qid, sizeof(struct kqid), h);
92
93         return h & GFS2_QD_HASH_MASK;
94 }
95
96 static inline void spin_lock_bucket(unsigned int hash)
97 {
98         hlist_bl_lock(&qd_hash_table[hash]);
99 }
100
101 static inline void spin_unlock_bucket(unsigned int hash)
102 {
103         hlist_bl_unlock(&qd_hash_table[hash]);
104 }
105
106 static void gfs2_qd_dealloc(struct rcu_head *rcu)
107 {
108         struct gfs2_quota_data *qd = container_of(rcu, struct gfs2_quota_data, qd_rcu);
109         kmem_cache_free(gfs2_quotad_cachep, qd);
110 }
111
112 static void gfs2_qd_dispose(struct list_head *list)
113 {
114         struct gfs2_quota_data *qd;
115         struct gfs2_sbd *sdp;
116
117         while (!list_empty(list)) {
118                 qd = list_first_entry(list, struct gfs2_quota_data, qd_lru);
119                 sdp = qd->qd_gl->gl_name.ln_sbd;
120
121                 list_del(&qd->qd_lru);
122
123                 /* Free from the filesystem-specific list */
124                 spin_lock(&qd_lock);
125                 list_del(&qd->qd_list);
126                 spin_unlock(&qd_lock);
127
128                 spin_lock_bucket(qd->qd_hash);
129                 hlist_bl_del_rcu(&qd->qd_hlist);
130                 spin_unlock_bucket(qd->qd_hash);
131
132                 gfs2_assert_warn(sdp, !qd->qd_change);
133                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
134                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
135
136                 gfs2_glock_put(qd->qd_gl);
137                 atomic_dec(&sdp->sd_quota_count);
138
139                 /* Delete it from the common reclaim list */
140                 call_rcu(&qd->qd_rcu, gfs2_qd_dealloc);
141         }
142 }
143
144
145 static enum lru_status gfs2_qd_isolate(struct list_head *item,
146                 struct list_lru_one *lru, spinlock_t *lru_lock, void *arg)
147 {
148         struct list_head *dispose = arg;
149         struct gfs2_quota_data *qd = list_entry(item, struct gfs2_quota_data, qd_lru);
150
151         if (!spin_trylock(&qd->qd_lockref.lock))
152                 return LRU_SKIP;
153
154         if (qd->qd_lockref.count == 0) {
155                 lockref_mark_dead(&qd->qd_lockref);
156                 list_lru_isolate_move(lru, &qd->qd_lru, dispose);
157         }
158
159         spin_unlock(&qd->qd_lockref.lock);
160         return LRU_REMOVED;
161 }
162
163 static unsigned long gfs2_qd_shrink_scan(struct shrinker *shrink,
164                                          struct shrink_control *sc)
165 {
166         LIST_HEAD(dispose);
167         unsigned long freed;
168
169         if (!(sc->gfp_mask & __GFP_FS))
170                 return SHRINK_STOP;
171
172         freed = list_lru_shrink_walk(&gfs2_qd_lru, sc,
173                                      gfs2_qd_isolate, &dispose);
174
175         gfs2_qd_dispose(&dispose);
176
177         return freed;
178 }
179
180 static unsigned long gfs2_qd_shrink_count(struct shrinker *shrink,
181                                           struct shrink_control *sc)
182 {
183         return vfs_pressure_ratio(list_lru_shrink_count(&gfs2_qd_lru, sc));
184 }
185
186 struct shrinker gfs2_qd_shrinker = {
187         .count_objects = gfs2_qd_shrink_count,
188         .scan_objects = gfs2_qd_shrink_scan,
189         .seeks = DEFAULT_SEEKS,
190         .flags = SHRINKER_NUMA_AWARE,
191 };
192
193
194 static u64 qd2index(struct gfs2_quota_data *qd)
195 {
196         struct kqid qid = qd->qd_id;
197         return (2 * (u64)from_kqid(&init_user_ns, qid)) +
198                 ((qid.type == USRQUOTA) ? 0 : 1);
199 }
200
201 static u64 qd2offset(struct gfs2_quota_data *qd)
202 {
203         u64 offset;
204
205         offset = qd2index(qd);
206         offset *= sizeof(struct gfs2_quota);
207
208         return offset;
209 }
210
211 static struct gfs2_quota_data *qd_alloc(unsigned hash, struct gfs2_sbd *sdp, struct kqid qid)
212 {
213         struct gfs2_quota_data *qd;
214         int error;
215
216         qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
217         if (!qd)
218                 return NULL;
219
220         qd->qd_sbd = sdp;
221         qd->qd_lockref.count = 1;
222         spin_lock_init(&qd->qd_lockref.lock);
223         qd->qd_id = qid;
224         qd->qd_slot = -1;
225         INIT_LIST_HEAD(&qd->qd_lru);
226         qd->qd_hash = hash;
227
228         error = gfs2_glock_get(sdp, qd2index(qd),
229                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
230         if (error)
231                 goto fail;
232
233         return qd;
234
235 fail:
236         kmem_cache_free(gfs2_quotad_cachep, qd);
237         return NULL;
238 }
239
240 static struct gfs2_quota_data *gfs2_qd_search_bucket(unsigned int hash,
241                                                      const struct gfs2_sbd *sdp,
242                                                      struct kqid qid)
243 {
244         struct gfs2_quota_data *qd;
245         struct hlist_bl_node *h;
246
247         hlist_bl_for_each_entry_rcu(qd, h, &qd_hash_table[hash], qd_hlist) {
248                 if (!qid_eq(qd->qd_id, qid))
249                         continue;
250                 if (qd->qd_sbd != sdp)
251                         continue;
252                 if (lockref_get_not_dead(&qd->qd_lockref)) {
253                         list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
254                         return qd;
255                 }
256         }
257
258         return NULL;
259 }
260
261
262 static int qd_get(struct gfs2_sbd *sdp, struct kqid qid,
263                   struct gfs2_quota_data **qdp)
264 {
265         struct gfs2_quota_data *qd, *new_qd;
266         unsigned int hash = gfs2_qd_hash(sdp, qid);
267
268         rcu_read_lock();
269         *qdp = qd = gfs2_qd_search_bucket(hash, sdp, qid);
270         rcu_read_unlock();
271
272         if (qd)
273                 return 0;
274
275         new_qd = qd_alloc(hash, sdp, qid);
276         if (!new_qd)
277                 return -ENOMEM;
278
279         spin_lock(&qd_lock);
280         spin_lock_bucket(hash);
281         *qdp = qd = gfs2_qd_search_bucket(hash, sdp, qid);
282         if (qd == NULL) {
283                 *qdp = new_qd;
284                 list_add(&new_qd->qd_list, &sdp->sd_quota_list);
285                 hlist_bl_add_head_rcu(&new_qd->qd_hlist, &qd_hash_table[hash]);
286                 atomic_inc(&sdp->sd_quota_count);
287         }
288         spin_unlock_bucket(hash);
289         spin_unlock(&qd_lock);
290
291         if (qd) {
292                 gfs2_glock_put(new_qd->qd_gl);
293                 kmem_cache_free(gfs2_quotad_cachep, new_qd);
294         }
295
296         return 0;
297 }
298
299
300 static void qd_hold(struct gfs2_quota_data *qd)
301 {
302         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
303         gfs2_assert(sdp, !__lockref_is_dead(&qd->qd_lockref));
304         lockref_get(&qd->qd_lockref);
305 }
306
307 static void qd_put(struct gfs2_quota_data *qd)
308 {
309         if (lockref_put_or_lock(&qd->qd_lockref))
310                 return;
311
312         qd->qd_lockref.count = 0;
313         list_lru_add(&gfs2_qd_lru, &qd->qd_lru);
314         spin_unlock(&qd->qd_lockref.lock);
315
316 }
317
318 static int slot_get(struct gfs2_quota_data *qd)
319 {
320         struct gfs2_sbd *sdp = qd->qd_sbd;
321         unsigned int bit;
322         int error = 0;
323
324         spin_lock(&sdp->sd_bitmap_lock);
325         if (qd->qd_slot_count != 0)
326                 goto out;
327
328         error = -ENOSPC;
329         bit = find_first_zero_bit(sdp->sd_quota_bitmap, sdp->sd_quota_slots);
330         if (bit < sdp->sd_quota_slots) {
331                 set_bit(bit, sdp->sd_quota_bitmap);
332                 qd->qd_slot = bit;
333                 error = 0;
334 out:
335                 qd->qd_slot_count++;
336         }
337         spin_unlock(&sdp->sd_bitmap_lock);
338
339         return error;
340 }
341
342 static void slot_hold(struct gfs2_quota_data *qd)
343 {
344         struct gfs2_sbd *sdp = qd->qd_sbd;
345
346         spin_lock(&sdp->sd_bitmap_lock);
347         gfs2_assert(sdp, qd->qd_slot_count);
348         qd->qd_slot_count++;
349         spin_unlock(&sdp->sd_bitmap_lock);
350 }
351
352 static void slot_put(struct gfs2_quota_data *qd)
353 {
354         struct gfs2_sbd *sdp = qd->qd_sbd;
355
356         spin_lock(&sdp->sd_bitmap_lock);
357         gfs2_assert(sdp, qd->qd_slot_count);
358         if (!--qd->qd_slot_count) {
359                 BUG_ON(!test_and_clear_bit(qd->qd_slot, sdp->sd_quota_bitmap));
360                 qd->qd_slot = -1;
361         }
362         spin_unlock(&sdp->sd_bitmap_lock);
363 }
364
365 static int bh_get(struct gfs2_quota_data *qd)
366 {
367         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
368         struct inode *inode = sdp->sd_qc_inode;
369         struct gfs2_inode *ip = GFS2_I(inode);
370         unsigned int block, offset;
371         struct buffer_head *bh;
372         struct iomap iomap = { };
373         int error;
374
375         mutex_lock(&sdp->sd_quota_mutex);
376
377         if (qd->qd_bh_count++) {
378                 mutex_unlock(&sdp->sd_quota_mutex);
379                 return 0;
380         }
381
382         block = qd->qd_slot / sdp->sd_qc_per_block;
383         offset = qd->qd_slot % sdp->sd_qc_per_block;
384
385         error = gfs2_iomap_get(inode,
386                                (loff_t)block << inode->i_blkbits,
387                                i_blocksize(inode), &iomap);
388         if (error)
389                 goto fail;
390         error = -ENOENT;
391         if (iomap.type != IOMAP_MAPPED)
392                 goto fail;
393
394         error = gfs2_meta_read(ip->i_gl, iomap.addr >> inode->i_blkbits,
395                                DIO_WAIT, 0, &bh);
396         if (error)
397                 goto fail;
398         error = -EIO;
399         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
400                 goto fail_brelse;
401
402         qd->qd_bh = bh;
403         qd->qd_bh_qc = (struct gfs2_quota_change *)
404                 (bh->b_data + sizeof(struct gfs2_meta_header) +
405                  offset * sizeof(struct gfs2_quota_change));
406
407         mutex_unlock(&sdp->sd_quota_mutex);
408
409         return 0;
410
411 fail_brelse:
412         brelse(bh);
413 fail:
414         qd->qd_bh_count--;
415         mutex_unlock(&sdp->sd_quota_mutex);
416         return error;
417 }
418
419 static void bh_put(struct gfs2_quota_data *qd)
420 {
421         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
422
423         mutex_lock(&sdp->sd_quota_mutex);
424         gfs2_assert(sdp, qd->qd_bh_count);
425         if (!--qd->qd_bh_count) {
426                 brelse(qd->qd_bh);
427                 qd->qd_bh = NULL;
428                 qd->qd_bh_qc = NULL;
429         }
430         mutex_unlock(&sdp->sd_quota_mutex);
431 }
432
433 static int qd_check_sync(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd,
434                          u64 *sync_gen)
435 {
436         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
437             !test_bit(QDF_CHANGE, &qd->qd_flags) ||
438             (sync_gen && (qd->qd_sync_gen >= *sync_gen)))
439                 return 0;
440
441         if (!lockref_get_not_dead(&qd->qd_lockref))
442                 return 0;
443
444         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
445         set_bit(QDF_LOCKED, &qd->qd_flags);
446         qd->qd_change_sync = qd->qd_change;
447         slot_hold(qd);
448         return 1;
449 }
450
451 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
452 {
453         struct gfs2_quota_data *qd = NULL, *iter;
454         int error;
455
456         *qdp = NULL;
457
458         if (sb_rdonly(sdp->sd_vfs))
459                 return 0;
460
461         spin_lock(&qd_lock);
462
463         list_for_each_entry(iter, &sdp->sd_quota_list, qd_list) {
464                 if (qd_check_sync(sdp, iter, &sdp->sd_quota_sync_gen)) {
465                         qd = iter;
466                         break;
467                 }
468         }
469
470         spin_unlock(&qd_lock);
471
472         if (qd) {
473                 gfs2_assert_warn(sdp, qd->qd_change_sync);
474                 error = bh_get(qd);
475                 if (error) {
476                         clear_bit(QDF_LOCKED, &qd->qd_flags);
477                         slot_put(qd);
478                         qd_put(qd);
479                         return error;
480                 }
481         }
482
483         *qdp = qd;
484
485         return 0;
486 }
487
488 static void qd_unlock(struct gfs2_quota_data *qd)
489 {
490         gfs2_assert_warn(qd->qd_gl->gl_name.ln_sbd,
491                          test_bit(QDF_LOCKED, &qd->qd_flags));
492         clear_bit(QDF_LOCKED, &qd->qd_flags);
493         bh_put(qd);
494         slot_put(qd);
495         qd_put(qd);
496 }
497
498 static int qdsb_get(struct gfs2_sbd *sdp, struct kqid qid,
499                     struct gfs2_quota_data **qdp)
500 {
501         int error;
502
503         error = qd_get(sdp, qid, qdp);
504         if (error)
505                 return error;
506
507         error = slot_get(*qdp);
508         if (error)
509                 goto fail;
510
511         error = bh_get(*qdp);
512         if (error)
513                 goto fail_slot;
514
515         return 0;
516
517 fail_slot:
518         slot_put(*qdp);
519 fail:
520         qd_put(*qdp);
521         return error;
522 }
523
524 static void qdsb_put(struct gfs2_quota_data *qd)
525 {
526         bh_put(qd);
527         slot_put(qd);
528         qd_put(qd);
529 }
530
531 /**
532  * gfs2_qa_get - make sure we have a quota allocations data structure,
533  *               if necessary
534  * @ip: the inode for this reservation
535  */
536 int gfs2_qa_get(struct gfs2_inode *ip)
537 {
538         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
539         struct inode *inode = &ip->i_inode;
540
541         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
542                 return 0;
543
544         spin_lock(&inode->i_lock);
545         if (ip->i_qadata == NULL) {
546                 struct gfs2_qadata *tmp;
547
548                 spin_unlock(&inode->i_lock);
549                 tmp = kmem_cache_zalloc(gfs2_qadata_cachep, GFP_NOFS);
550                 if (!tmp)
551                         return -ENOMEM;
552
553                 spin_lock(&inode->i_lock);
554                 if (ip->i_qadata == NULL)
555                         ip->i_qadata = tmp;
556                 else
557                         kmem_cache_free(gfs2_qadata_cachep, tmp);
558         }
559         ip->i_qadata->qa_ref++;
560         spin_unlock(&inode->i_lock);
561         return 0;
562 }
563
564 void gfs2_qa_put(struct gfs2_inode *ip)
565 {
566         struct inode *inode = &ip->i_inode;
567
568         spin_lock(&inode->i_lock);
569         if (ip->i_qadata && --ip->i_qadata->qa_ref == 0) {
570                 kmem_cache_free(gfs2_qadata_cachep, ip->i_qadata);
571                 ip->i_qadata = NULL;
572         }
573         spin_unlock(&inode->i_lock);
574 }
575
576 int gfs2_quota_hold(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
577 {
578         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
579         struct gfs2_quota_data **qd;
580         int error;
581
582         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
583                 return 0;
584
585         error = gfs2_qa_get(ip);
586         if (error)
587                 return error;
588
589         qd = ip->i_qadata->qa_qd;
590
591         if (gfs2_assert_warn(sdp, !ip->i_qadata->qa_qd_num) ||
592             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags))) {
593                 error = -EIO;
594                 goto out;
595         }
596
597         error = qdsb_get(sdp, make_kqid_uid(ip->i_inode.i_uid), qd);
598         if (error)
599                 goto out_unhold;
600         ip->i_qadata->qa_qd_num++;
601         qd++;
602
603         error = qdsb_get(sdp, make_kqid_gid(ip->i_inode.i_gid), qd);
604         if (error)
605                 goto out_unhold;
606         ip->i_qadata->qa_qd_num++;
607         qd++;
608
609         if (!uid_eq(uid, NO_UID_QUOTA_CHANGE) &&
610             !uid_eq(uid, ip->i_inode.i_uid)) {
611                 error = qdsb_get(sdp, make_kqid_uid(uid), qd);
612                 if (error)
613                         goto out_unhold;
614                 ip->i_qadata->qa_qd_num++;
615                 qd++;
616         }
617
618         if (!gid_eq(gid, NO_GID_QUOTA_CHANGE) &&
619             !gid_eq(gid, ip->i_inode.i_gid)) {
620                 error = qdsb_get(sdp, make_kqid_gid(gid), qd);
621                 if (error)
622                         goto out_unhold;
623                 ip->i_qadata->qa_qd_num++;
624                 qd++;
625         }
626
627 out_unhold:
628         if (error)
629                 gfs2_quota_unhold(ip);
630 out:
631         return error;
632 }
633
634 void gfs2_quota_unhold(struct gfs2_inode *ip)
635 {
636         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
637         u32 x;
638
639         if (ip->i_qadata == NULL)
640                 return;
641
642         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
643
644         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
645                 qdsb_put(ip->i_qadata->qa_qd[x]);
646                 ip->i_qadata->qa_qd[x] = NULL;
647         }
648         ip->i_qadata->qa_qd_num = 0;
649         gfs2_qa_put(ip);
650 }
651
652 static int sort_qd(const void *a, const void *b)
653 {
654         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
655         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
656
657         if (qid_lt(qd_a->qd_id, qd_b->qd_id))
658                 return -1;
659         if (qid_lt(qd_b->qd_id, qd_a->qd_id))
660                 return 1;
661         return 0;
662 }
663
664 static void do_qc(struct gfs2_quota_data *qd, s64 change)
665 {
666         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
667         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
668         struct gfs2_quota_change *qc = qd->qd_bh_qc;
669         s64 x;
670
671         mutex_lock(&sdp->sd_quota_mutex);
672         gfs2_trans_add_meta(ip->i_gl, qd->qd_bh);
673
674         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
675                 qc->qc_change = 0;
676                 qc->qc_flags = 0;
677                 if (qd->qd_id.type == USRQUOTA)
678                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
679                 qc->qc_id = cpu_to_be32(from_kqid(&init_user_ns, qd->qd_id));
680         }
681
682         x = be64_to_cpu(qc->qc_change) + change;
683         qc->qc_change = cpu_to_be64(x);
684
685         spin_lock(&qd_lock);
686         qd->qd_change = x;
687         spin_unlock(&qd_lock);
688
689         if (!x) {
690                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
691                 clear_bit(QDF_CHANGE, &qd->qd_flags);
692                 qc->qc_flags = 0;
693                 qc->qc_id = 0;
694                 slot_put(qd);
695                 qd_put(qd);
696         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
697                 qd_hold(qd);
698                 slot_hold(qd);
699         }
700
701         if (change < 0) /* Reset quiet flag if we freed some blocks */
702                 clear_bit(QDF_QMSG_QUIET, &qd->qd_flags);
703         mutex_unlock(&sdp->sd_quota_mutex);
704 }
705
706 static int gfs2_write_buf_to_page(struct gfs2_inode *ip, unsigned long index,
707                                   unsigned off, void *buf, unsigned bytes)
708 {
709         struct inode *inode = &ip->i_inode;
710         struct gfs2_sbd *sdp = GFS2_SB(inode);
711         struct address_space *mapping = inode->i_mapping;
712         struct page *page;
713         struct buffer_head *bh;
714         void *kaddr;
715         u64 blk;
716         unsigned bsize = sdp->sd_sb.sb_bsize, bnum = 0, boff = 0;
717         unsigned to_write = bytes, pg_off = off;
718         int done = 0;
719
720         blk = index << (PAGE_SHIFT - sdp->sd_sb.sb_bsize_shift);
721         boff = off % bsize;
722
723         page = find_or_create_page(mapping, index, GFP_NOFS);
724         if (!page)
725                 return -ENOMEM;
726         if (!page_has_buffers(page))
727                 create_empty_buffers(page, bsize, 0);
728
729         bh = page_buffers(page);
730         while (!done) {
731                 /* Find the beginning block within the page */
732                 if (pg_off >= ((bnum * bsize) + bsize)) {
733                         bh = bh->b_this_page;
734                         bnum++;
735                         blk++;
736                         continue;
737                 }
738                 if (!buffer_mapped(bh)) {
739                         gfs2_block_map(inode, blk, bh, 1);
740                         if (!buffer_mapped(bh))
741                                 goto unlock_out;
742                         /* If it's a newly allocated disk block, zero it */
743                         if (buffer_new(bh))
744                                 zero_user(page, bnum * bsize, bh->b_size);
745                 }
746                 if (PageUptodate(page))
747                         set_buffer_uptodate(bh);
748                 if (bh_read(bh, REQ_META | REQ_PRIO) < 0)
749                         goto unlock_out;
750                 if (gfs2_is_jdata(ip))
751                         gfs2_trans_add_data(ip->i_gl, bh);
752                 else
753                         gfs2_ordered_add_inode(ip);
754
755                 /* If we need to write to the next block as well */
756                 if (to_write > (bsize - boff)) {
757                         pg_off += (bsize - boff);
758                         to_write -= (bsize - boff);
759                         boff = pg_off % bsize;
760                         continue;
761                 }
762                 done = 1;
763         }
764
765         /* Write to the page, now that we have setup the buffer(s) */
766         kaddr = kmap_atomic(page);
767         memcpy(kaddr + off, buf, bytes);
768         flush_dcache_page(page);
769         kunmap_atomic(kaddr);
770         unlock_page(page);
771         put_page(page);
772
773         return 0;
774
775 unlock_out:
776         unlock_page(page);
777         put_page(page);
778         return -EIO;
779 }
780
781 static int gfs2_write_disk_quota(struct gfs2_inode *ip, struct gfs2_quota *qp,
782                                  loff_t loc)
783 {
784         unsigned long pg_beg;
785         unsigned pg_off, nbytes, overflow = 0;
786         int pg_oflow = 0, error;
787         void *ptr;
788
789         nbytes = sizeof(struct gfs2_quota);
790
791         pg_beg = loc >> PAGE_SHIFT;
792         pg_off = offset_in_page(loc);
793
794         /* If the quota straddles a page boundary, split the write in two */
795         if ((pg_off + nbytes) > PAGE_SIZE) {
796                 pg_oflow = 1;
797                 overflow = (pg_off + nbytes) - PAGE_SIZE;
798         }
799
800         ptr = qp;
801         error = gfs2_write_buf_to_page(ip, pg_beg, pg_off, ptr,
802                                        nbytes - overflow);
803         /* If there's an overflow, write the remaining bytes to the next page */
804         if (!error && pg_oflow)
805                 error = gfs2_write_buf_to_page(ip, pg_beg + 1, 0,
806                                                ptr + nbytes - overflow,
807                                                overflow);
808         return error;
809 }
810
811 /**
812  * gfs2_adjust_quota - adjust record of current block usage
813  * @ip: The quota inode
814  * @loc: Offset of the entry in the quota file
815  * @change: The amount of usage change to record
816  * @qd: The quota data
817  * @fdq: The updated limits to record
818  *
819  * This function was mostly borrowed from gfs2_block_truncate_page which was
820  * in turn mostly borrowed from ext3
821  *
822  * Returns: 0 or -ve on error
823  */
824
825 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
826                              s64 change, struct gfs2_quota_data *qd,
827                              struct qc_dqblk *fdq)
828 {
829         struct inode *inode = &ip->i_inode;
830         struct gfs2_sbd *sdp = GFS2_SB(inode);
831         struct gfs2_quota q;
832         int err;
833         u64 size;
834
835         if (gfs2_is_stuffed(ip)) {
836                 err = gfs2_unstuff_dinode(ip);
837                 if (err)
838                         return err;
839         }
840
841         memset(&q, 0, sizeof(struct gfs2_quota));
842         err = gfs2_internal_read(ip, (char *)&q, &loc, sizeof(q));
843         if (err < 0)
844                 return err;
845
846         loc -= sizeof(q); /* gfs2_internal_read would've advanced the loc ptr */
847         err = -EIO;
848         be64_add_cpu(&q.qu_value, change);
849         if (((s64)be64_to_cpu(q.qu_value)) < 0)
850                 q.qu_value = 0; /* Never go negative on quota usage */
851         qd->qd_qb.qb_value = q.qu_value;
852         if (fdq) {
853                 if (fdq->d_fieldmask & QC_SPC_SOFT) {
854                         q.qu_warn = cpu_to_be64(fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift);
855                         qd->qd_qb.qb_warn = q.qu_warn;
856                 }
857                 if (fdq->d_fieldmask & QC_SPC_HARD) {
858                         q.qu_limit = cpu_to_be64(fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift);
859                         qd->qd_qb.qb_limit = q.qu_limit;
860                 }
861                 if (fdq->d_fieldmask & QC_SPACE) {
862                         q.qu_value = cpu_to_be64(fdq->d_space >> sdp->sd_sb.sb_bsize_shift);
863                         qd->qd_qb.qb_value = q.qu_value;
864                 }
865         }
866
867         err = gfs2_write_disk_quota(ip, &q, loc);
868         if (!err) {
869                 size = loc + sizeof(struct gfs2_quota);
870                 if (size > inode->i_size)
871                         i_size_write(inode, size);
872                 inode->i_mtime = inode->i_atime = current_time(inode);
873                 mark_inode_dirty(inode);
874                 set_bit(QDF_REFRESH, &qd->qd_flags);
875         }
876
877         return err;
878 }
879
880 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
881 {
882         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_name.ln_sbd;
883         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
884         struct gfs2_alloc_parms ap = { .aflags = 0, };
885         unsigned int data_blocks, ind_blocks;
886         struct gfs2_holder *ghs, i_gh;
887         unsigned int qx, x;
888         struct gfs2_quota_data *qd;
889         unsigned reserved;
890         loff_t offset;
891         unsigned int nalloc = 0, blocks;
892         int error;
893
894         error = gfs2_qa_get(ip);
895         if (error)
896                 return error;
897
898         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
899                               &data_blocks, &ind_blocks);
900
901         ghs = kmalloc_array(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
902         if (!ghs) {
903                 error = -ENOMEM;
904                 goto out;
905         }
906
907         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
908         inode_lock(&ip->i_inode);
909         for (qx = 0; qx < num_qd; qx++) {
910                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
911                                            GL_NOCACHE, &ghs[qx]);
912                 if (error)
913                         goto out_dq;
914         }
915
916         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
917         if (error)
918                 goto out_dq;
919
920         for (x = 0; x < num_qd; x++) {
921                 offset = qd2offset(qda[x]);
922                 if (gfs2_write_alloc_required(ip, offset,
923                                               sizeof(struct gfs2_quota)))
924                         nalloc++;
925         }
926
927         /* 
928          * 1 blk for unstuffing inode if stuffed. We add this extra
929          * block to the reservation unconditionally. If the inode
930          * doesn't need unstuffing, the block will be released to the 
931          * rgrp since it won't be allocated during the transaction
932          */
933         /* +3 in the end for unstuffing block, inode size update block
934          * and another block in case quota straddles page boundary and 
935          * two blocks need to be updated instead of 1 */
936         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
937
938         reserved = 1 + (nalloc * (data_blocks + ind_blocks));
939         ap.target = reserved;
940         error = gfs2_inplace_reserve(ip, &ap);
941         if (error)
942                 goto out_alloc;
943
944         if (nalloc)
945                 blocks += gfs2_rg_blocks(ip, reserved) + nalloc * ind_blocks + RES_STATFS;
946
947         error = gfs2_trans_begin(sdp, blocks, 0);
948         if (error)
949                 goto out_ipres;
950
951         for (x = 0; x < num_qd; x++) {
952                 qd = qda[x];
953                 offset = qd2offset(qd);
954                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
955                 if (error)
956                         goto out_end_trans;
957
958                 do_qc(qd, -qd->qd_change_sync);
959                 set_bit(QDF_REFRESH, &qd->qd_flags);
960         }
961
962         error = 0;
963
964 out_end_trans:
965         gfs2_trans_end(sdp);
966 out_ipres:
967         gfs2_inplace_release(ip);
968 out_alloc:
969         gfs2_glock_dq_uninit(&i_gh);
970 out_dq:
971         while (qx--)
972                 gfs2_glock_dq_uninit(&ghs[qx]);
973         inode_unlock(&ip->i_inode);
974         kfree(ghs);
975         gfs2_log_flush(ip->i_gl->gl_name.ln_sbd, ip->i_gl,
976                        GFS2_LOG_HEAD_FLUSH_NORMAL | GFS2_LFC_DO_SYNC);
977 out:
978         gfs2_qa_put(ip);
979         return error;
980 }
981
982 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
983 {
984         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
985         struct gfs2_quota q;
986         struct gfs2_quota_lvb *qlvb;
987         loff_t pos;
988         int error;
989
990         memset(&q, 0, sizeof(struct gfs2_quota));
991         pos = qd2offset(qd);
992         error = gfs2_internal_read(ip, (char *)&q, &pos, sizeof(q));
993         if (error < 0)
994                 return error;
995
996         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
997         qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
998         qlvb->__pad = 0;
999         qlvb->qb_limit = q.qu_limit;
1000         qlvb->qb_warn = q.qu_warn;
1001         qlvb->qb_value = q.qu_value;
1002         qd->qd_qb = *qlvb;
1003
1004         return 0;
1005 }
1006
1007 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
1008                     struct gfs2_holder *q_gh)
1009 {
1010         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1011         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1012         struct gfs2_holder i_gh;
1013         int error;
1014
1015 restart:
1016         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
1017         if (error)
1018                 return error;
1019
1020         if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
1021                 force_refresh = FORCE;
1022
1023         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1024
1025         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
1026                 gfs2_glock_dq_uninit(q_gh);
1027                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
1028                                            GL_NOCACHE, q_gh);
1029                 if (error)
1030                         return error;
1031
1032                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
1033                 if (error)
1034                         goto fail;
1035
1036                 error = update_qd(sdp, qd);
1037                 if (error)
1038                         goto fail_gunlock;
1039
1040                 gfs2_glock_dq_uninit(&i_gh);
1041                 gfs2_glock_dq_uninit(q_gh);
1042                 force_refresh = 0;
1043                 goto restart;
1044         }
1045
1046         return 0;
1047
1048 fail_gunlock:
1049         gfs2_glock_dq_uninit(&i_gh);
1050 fail:
1051         gfs2_glock_dq_uninit(q_gh);
1052         return error;
1053 }
1054
1055 int gfs2_quota_lock(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
1056 {
1057         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1058         struct gfs2_quota_data *qd;
1059         u32 x;
1060         int error = 0;
1061
1062         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1063                 return 0;
1064
1065         error = gfs2_quota_hold(ip, uid, gid);
1066         if (error)
1067                 return error;
1068
1069         sort(ip->i_qadata->qa_qd, ip->i_qadata->qa_qd_num,
1070              sizeof(struct gfs2_quota_data *), sort_qd, NULL);
1071
1072         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1073                 qd = ip->i_qadata->qa_qd[x];
1074                 error = do_glock(qd, NO_FORCE, &ip->i_qadata->qa_qd_ghs[x]);
1075                 if (error)
1076                         break;
1077         }
1078
1079         if (!error)
1080                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
1081         else {
1082                 while (x--)
1083                         gfs2_glock_dq_uninit(&ip->i_qadata->qa_qd_ghs[x]);
1084                 gfs2_quota_unhold(ip);
1085         }
1086
1087         return error;
1088 }
1089
1090 static int need_sync(struct gfs2_quota_data *qd)
1091 {
1092         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1093         struct gfs2_tune *gt = &sdp->sd_tune;
1094         s64 value;
1095         unsigned int num, den;
1096         int do_sync = 1;
1097
1098         if (!qd->qd_qb.qb_limit)
1099                 return 0;
1100
1101         spin_lock(&qd_lock);
1102         value = qd->qd_change;
1103         spin_unlock(&qd_lock);
1104
1105         spin_lock(&gt->gt_spin);
1106         num = gt->gt_quota_scale_num;
1107         den = gt->gt_quota_scale_den;
1108         spin_unlock(&gt->gt_spin);
1109
1110         if (value < 0)
1111                 do_sync = 0;
1112         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
1113                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1114                 do_sync = 0;
1115         else {
1116                 value *= gfs2_jindex_size(sdp) * num;
1117                 value = div_s64(value, den);
1118                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
1119                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1120                         do_sync = 0;
1121         }
1122
1123         return do_sync;
1124 }
1125
1126 void gfs2_quota_unlock(struct gfs2_inode *ip)
1127 {
1128         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1129         struct gfs2_quota_data *qda[4];
1130         unsigned int count = 0;
1131         u32 x;
1132         int found;
1133
1134         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1135                 return;
1136
1137         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1138                 struct gfs2_quota_data *qd;
1139                 int sync;
1140
1141                 qd = ip->i_qadata->qa_qd[x];
1142                 sync = need_sync(qd);
1143
1144                 gfs2_glock_dq_uninit(&ip->i_qadata->qa_qd_ghs[x]);
1145                 if (!sync)
1146                         continue;
1147
1148                 spin_lock(&qd_lock);
1149                 found = qd_check_sync(sdp, qd, NULL);
1150                 spin_unlock(&qd_lock);
1151
1152                 if (!found)
1153                         continue;
1154
1155                 gfs2_assert_warn(sdp, qd->qd_change_sync);
1156                 if (bh_get(qd)) {
1157                         clear_bit(QDF_LOCKED, &qd->qd_flags);
1158                         slot_put(qd);
1159                         qd_put(qd);
1160                         continue;
1161                 }
1162
1163                 qda[count++] = qd;
1164         }
1165
1166         if (count) {
1167                 do_sync(count, qda);
1168                 for (x = 0; x < count; x++)
1169                         qd_unlock(qda[x]);
1170         }
1171
1172         gfs2_quota_unhold(ip);
1173 }
1174
1175 #define MAX_LINE 256
1176
1177 static int print_message(struct gfs2_quota_data *qd, char *type)
1178 {
1179         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1180
1181         fs_info(sdp, "quota %s for %s %u\n",
1182                 type,
1183                 (qd->qd_id.type == USRQUOTA) ? "user" : "group",
1184                 from_kqid(&init_user_ns, qd->qd_id));
1185
1186         return 0;
1187 }
1188
1189 /**
1190  * gfs2_quota_check - check if allocating new blocks will exceed quota
1191  * @ip:  The inode for which this check is being performed
1192  * @uid: The uid to check against
1193  * @gid: The gid to check against
1194  * @ap:  The allocation parameters. ap->target contains the requested
1195  *       blocks. ap->min_target, if set, contains the minimum blks
1196  *       requested.
1197  *
1198  * Returns: 0 on success.
1199  *                  min_req = ap->min_target ? ap->min_target : ap->target;
1200  *                  quota must allow at least min_req blks for success and
1201  *                  ap->allowed is set to the number of blocks allowed
1202  *
1203  *          -EDQUOT otherwise, quota violation. ap->allowed is set to number
1204  *                  of blocks available.
1205  */
1206 int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid,
1207                      struct gfs2_alloc_parms *ap)
1208 {
1209         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1210         struct gfs2_quota_data *qd;
1211         s64 value, warn, limit;
1212         u32 x;
1213         int error = 0;
1214
1215         ap->allowed = UINT_MAX; /* Assume we are permitted a whole lot */
1216         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1217                 return 0;
1218
1219         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1220                 qd = ip->i_qadata->qa_qd[x];
1221
1222                 if (!(qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1223                       qid_eq(qd->qd_id, make_kqid_gid(gid))))
1224                         continue;
1225
1226                 warn = (s64)be64_to_cpu(qd->qd_qb.qb_warn);
1227                 limit = (s64)be64_to_cpu(qd->qd_qb.qb_limit);
1228                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1229                 spin_lock(&qd_lock);
1230                 value += qd->qd_change;
1231                 spin_unlock(&qd_lock);
1232
1233                 if (limit > 0 && (limit - value) < ap->allowed)
1234                         ap->allowed = limit - value;
1235                 /* If we can't meet the target */
1236                 if (limit && limit < (value + (s64)ap->target)) {
1237                         /* If no min_target specified or we don't meet
1238                          * min_target, return -EDQUOT */
1239                         if (!ap->min_target || ap->min_target > ap->allowed) {
1240                                 if (!test_and_set_bit(QDF_QMSG_QUIET,
1241                                                       &qd->qd_flags)) {
1242                                         print_message(qd, "exceeded");
1243                                         quota_send_warning(qd->qd_id,
1244                                                            sdp->sd_vfs->s_dev,
1245                                                            QUOTA_NL_BHARDWARN);
1246                                 }
1247                                 error = -EDQUOT;
1248                                 break;
1249                         }
1250                 } else if (warn && warn < value &&
1251                            time_after_eq(jiffies, qd->qd_last_warn +
1252                                          gfs2_tune_get(sdp, gt_quota_warn_period)
1253                                          * HZ)) {
1254                         quota_send_warning(qd->qd_id,
1255                                            sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1256                         error = print_message(qd, "warning");
1257                         qd->qd_last_warn = jiffies;
1258                 }
1259         }
1260         return error;
1261 }
1262
1263 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1264                        kuid_t uid, kgid_t gid)
1265 {
1266         struct gfs2_quota_data *qd;
1267         u32 x;
1268         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1269
1270         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON ||
1271             gfs2_assert_warn(sdp, change))
1272                 return;
1273         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1274                 return;
1275
1276         if (gfs2_assert_withdraw(sdp, ip->i_qadata &&
1277                                  ip->i_qadata->qa_ref > 0))
1278                 return;
1279         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1280                 qd = ip->i_qadata->qa_qd[x];
1281
1282                 if (qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1283                     qid_eq(qd->qd_id, make_kqid_gid(gid))) {
1284                         do_qc(qd, change);
1285                 }
1286         }
1287 }
1288
1289 int gfs2_quota_sync(struct super_block *sb, int type)
1290 {
1291         struct gfs2_sbd *sdp = sb->s_fs_info;
1292         struct gfs2_quota_data **qda;
1293         unsigned int max_qd = PAGE_SIZE / sizeof(struct gfs2_holder);
1294         unsigned int num_qd;
1295         unsigned int x;
1296         int error = 0;
1297
1298         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1299         if (!qda)
1300                 return -ENOMEM;
1301
1302         mutex_lock(&sdp->sd_quota_sync_mutex);
1303         sdp->sd_quota_sync_gen++;
1304
1305         do {
1306                 num_qd = 0;
1307
1308                 for (;;) {
1309                         error = qd_fish(sdp, qda + num_qd);
1310                         if (error || !qda[num_qd])
1311                                 break;
1312                         if (++num_qd == max_qd)
1313                                 break;
1314                 }
1315
1316                 if (num_qd) {
1317                         if (!error)
1318                                 error = do_sync(num_qd, qda);
1319                         if (!error)
1320                                 for (x = 0; x < num_qd; x++)
1321                                         qda[x]->qd_sync_gen =
1322                                                 sdp->sd_quota_sync_gen;
1323
1324                         for (x = 0; x < num_qd; x++)
1325                                 qd_unlock(qda[x]);
1326                 }
1327         } while (!error && num_qd == max_qd);
1328
1329         mutex_unlock(&sdp->sd_quota_sync_mutex);
1330         kfree(qda);
1331
1332         return error;
1333 }
1334
1335 int gfs2_quota_refresh(struct gfs2_sbd *sdp, struct kqid qid)
1336 {
1337         struct gfs2_quota_data *qd;
1338         struct gfs2_holder q_gh;
1339         int error;
1340
1341         error = qd_get(sdp, qid, &qd);
1342         if (error)
1343                 return error;
1344
1345         error = do_glock(qd, FORCE, &q_gh);
1346         if (!error)
1347                 gfs2_glock_dq_uninit(&q_gh);
1348
1349         qd_put(qd);
1350         return error;
1351 }
1352
1353 int gfs2_quota_init(struct gfs2_sbd *sdp)
1354 {
1355         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1356         u64 size = i_size_read(sdp->sd_qc_inode);
1357         unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1358         unsigned int x, slot = 0;
1359         unsigned int found = 0;
1360         unsigned int hash;
1361         unsigned int bm_size;
1362         u64 dblock;
1363         u32 extlen = 0;
1364         int error;
1365
1366         if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1367                 return -EIO;
1368
1369         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1370         bm_size = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * sizeof(unsigned long));
1371         bm_size *= sizeof(unsigned long);
1372         error = -ENOMEM;
1373         sdp->sd_quota_bitmap = kzalloc(bm_size, GFP_NOFS | __GFP_NOWARN);
1374         if (sdp->sd_quota_bitmap == NULL)
1375                 sdp->sd_quota_bitmap = __vmalloc(bm_size, GFP_NOFS |
1376                                                  __GFP_ZERO);
1377         if (!sdp->sd_quota_bitmap)
1378                 return error;
1379
1380         for (x = 0; x < blocks; x++) {
1381                 struct buffer_head *bh;
1382                 const struct gfs2_quota_change *qc;
1383                 unsigned int y;
1384
1385                 if (!extlen) {
1386                         extlen = 32;
1387                         error = gfs2_get_extent(&ip->i_inode, x, &dblock, &extlen);
1388                         if (error)
1389                                 goto fail;
1390                 }
1391                 error = -EIO;
1392                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1393                 if (!bh)
1394                         goto fail;
1395                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1396                         brelse(bh);
1397                         goto fail;
1398                 }
1399
1400                 qc = (const struct gfs2_quota_change *)(bh->b_data + sizeof(struct gfs2_meta_header));
1401                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1402                      y++, slot++) {
1403                         struct gfs2_quota_data *qd;
1404                         s64 qc_change = be64_to_cpu(qc->qc_change);
1405                         u32 qc_flags = be32_to_cpu(qc->qc_flags);
1406                         enum quota_type qtype = (qc_flags & GFS2_QCF_USER) ?
1407                                                 USRQUOTA : GRPQUOTA;
1408                         struct kqid qc_id = make_kqid(&init_user_ns, qtype,
1409                                                       be32_to_cpu(qc->qc_id));
1410                         qc++;
1411                         if (!qc_change)
1412                                 continue;
1413
1414                         hash = gfs2_qd_hash(sdp, qc_id);
1415                         qd = qd_alloc(hash, sdp, qc_id);
1416                         if (qd == NULL) {
1417                                 brelse(bh);
1418                                 goto fail;
1419                         }
1420
1421                         set_bit(QDF_CHANGE, &qd->qd_flags);
1422                         qd->qd_change = qc_change;
1423                         qd->qd_slot = slot;
1424                         qd->qd_slot_count = 1;
1425
1426                         spin_lock(&qd_lock);
1427                         BUG_ON(test_and_set_bit(slot, sdp->sd_quota_bitmap));
1428                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1429                         atomic_inc(&sdp->sd_quota_count);
1430                         spin_unlock(&qd_lock);
1431
1432                         spin_lock_bucket(hash);
1433                         hlist_bl_add_head_rcu(&qd->qd_hlist, &qd_hash_table[hash]);
1434                         spin_unlock_bucket(hash);
1435
1436                         found++;
1437                 }
1438
1439                 brelse(bh);
1440                 dblock++;
1441                 extlen--;
1442         }
1443
1444         if (found)
1445                 fs_info(sdp, "found %u quota changes\n", found);
1446
1447         return 0;
1448
1449 fail:
1450         gfs2_quota_cleanup(sdp);
1451         return error;
1452 }
1453
1454 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1455 {
1456         struct list_head *head = &sdp->sd_quota_list;
1457         struct gfs2_quota_data *qd;
1458
1459         spin_lock(&qd_lock);
1460         while (!list_empty(head)) {
1461                 qd = list_last_entry(head, struct gfs2_quota_data, qd_list);
1462
1463                 list_del(&qd->qd_list);
1464
1465                 /* Also remove if this qd exists in the reclaim list */
1466                 list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
1467                 atomic_dec(&sdp->sd_quota_count);
1468                 spin_unlock(&qd_lock);
1469
1470                 spin_lock_bucket(qd->qd_hash);
1471                 hlist_bl_del_rcu(&qd->qd_hlist);
1472                 spin_unlock_bucket(qd->qd_hash);
1473
1474                 gfs2_assert_warn(sdp, !qd->qd_change);
1475                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1476                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1477
1478                 gfs2_glock_put(qd->qd_gl);
1479                 call_rcu(&qd->qd_rcu, gfs2_qd_dealloc);
1480
1481                 spin_lock(&qd_lock);
1482         }
1483         spin_unlock(&qd_lock);
1484
1485         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1486
1487         kvfree(sdp->sd_quota_bitmap);
1488         sdp->sd_quota_bitmap = NULL;
1489 }
1490
1491 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1492 {
1493         if (error == 0 || error == -EROFS)
1494                 return;
1495         if (!gfs2_withdrawn(sdp)) {
1496                 if (!cmpxchg(&sdp->sd_log_error, 0, error))
1497                         fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1498                 wake_up(&sdp->sd_logd_waitq);
1499         }
1500 }
1501
1502 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1503                                int (*fxn)(struct super_block *sb, int type),
1504                                unsigned long t, unsigned long *timeo,
1505                                unsigned int *new_timeo)
1506 {
1507         if (t >= *timeo) {
1508                 int error = fxn(sdp->sd_vfs, 0);
1509                 quotad_error(sdp, msg, error);
1510                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1511         } else {
1512                 *timeo -= t;
1513         }
1514 }
1515
1516 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1517         if (!sdp->sd_statfs_force_sync) {
1518                 sdp->sd_statfs_force_sync = 1;
1519                 wake_up(&sdp->sd_quota_wait);
1520         }
1521 }
1522
1523
1524 /**
1525  * gfs2_quotad - Write cached quota changes into the quota file
1526  * @data: Pointer to GFS2 superblock
1527  *
1528  */
1529
1530 int gfs2_quotad(void *data)
1531 {
1532         struct gfs2_sbd *sdp = data;
1533         struct gfs2_tune *tune = &sdp->sd_tune;
1534         unsigned long statfs_timeo = 0;
1535         unsigned long quotad_timeo = 0;
1536         unsigned long t = 0;
1537         DEFINE_WAIT(wait);
1538
1539         while (!kthread_should_stop()) {
1540
1541                 if (gfs2_withdrawn(sdp))
1542                         goto bypass;
1543                 /* Update the master statfs file */
1544                 if (sdp->sd_statfs_force_sync) {
1545                         int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1546                         quotad_error(sdp, "statfs", error);
1547                         statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1548                 }
1549                 else
1550                         quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1551                                            &statfs_timeo,
1552                                            &tune->gt_statfs_quantum);
1553
1554                 /* Update quota file */
1555                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
1556                                    &quotad_timeo, &tune->gt_quota_quantum);
1557
1558                 try_to_freeze();
1559
1560 bypass:
1561                 t = min(quotad_timeo, statfs_timeo);
1562
1563                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1564                 if (!sdp->sd_statfs_force_sync)
1565                         t -= schedule_timeout(t);
1566                 else
1567                         t = 0;
1568                 finish_wait(&sdp->sd_quota_wait, &wait);
1569         }
1570
1571         return 0;
1572 }
1573
1574 static int gfs2_quota_get_state(struct super_block *sb, struct qc_state *state)
1575 {
1576         struct gfs2_sbd *sdp = sb->s_fs_info;
1577
1578         memset(state, 0, sizeof(*state));
1579
1580         switch (sdp->sd_args.ar_quota) {
1581         case GFS2_QUOTA_ON:
1582                 state->s_state[USRQUOTA].flags |= QCI_LIMITS_ENFORCED;
1583                 state->s_state[GRPQUOTA].flags |= QCI_LIMITS_ENFORCED;
1584                 fallthrough;
1585         case GFS2_QUOTA_ACCOUNT:
1586                 state->s_state[USRQUOTA].flags |= QCI_ACCT_ENABLED |
1587                                                   QCI_SYSFILE;
1588                 state->s_state[GRPQUOTA].flags |= QCI_ACCT_ENABLED |
1589                                                   QCI_SYSFILE;
1590                 break;
1591         case GFS2_QUOTA_OFF:
1592                 break;
1593         }
1594         if (sdp->sd_quota_inode) {
1595                 state->s_state[USRQUOTA].ino =
1596                                         GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1597                 state->s_state[USRQUOTA].blocks = sdp->sd_quota_inode->i_blocks;
1598         }
1599         state->s_state[USRQUOTA].nextents = 1;  /* unsupported */
1600         state->s_state[GRPQUOTA] = state->s_state[USRQUOTA];
1601         state->s_incoredqs = list_lru_count(&gfs2_qd_lru);
1602         return 0;
1603 }
1604
1605 static int gfs2_get_dqblk(struct super_block *sb, struct kqid qid,
1606                           struct qc_dqblk *fdq)
1607 {
1608         struct gfs2_sbd *sdp = sb->s_fs_info;
1609         struct gfs2_quota_lvb *qlvb;
1610         struct gfs2_quota_data *qd;
1611         struct gfs2_holder q_gh;
1612         int error;
1613
1614         memset(fdq, 0, sizeof(*fdq));
1615
1616         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1617                 return -ESRCH; /* Crazy XFS error code */
1618
1619         if ((qid.type != USRQUOTA) &&
1620             (qid.type != GRPQUOTA))
1621                 return -EINVAL;
1622
1623         error = qd_get(sdp, qid, &qd);
1624         if (error)
1625                 return error;
1626         error = do_glock(qd, FORCE, &q_gh);
1627         if (error)
1628                 goto out;
1629
1630         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1631         fdq->d_spc_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_sb.sb_bsize_shift;
1632         fdq->d_spc_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_sb.sb_bsize_shift;
1633         fdq->d_space = be64_to_cpu(qlvb->qb_value) << sdp->sd_sb.sb_bsize_shift;
1634
1635         gfs2_glock_dq_uninit(&q_gh);
1636 out:
1637         qd_put(qd);
1638         return error;
1639 }
1640
1641 /* GFS2 only supports a subset of the XFS fields */
1642 #define GFS2_FIELDMASK (QC_SPC_SOFT|QC_SPC_HARD|QC_SPACE)
1643
1644 static int gfs2_set_dqblk(struct super_block *sb, struct kqid qid,
1645                           struct qc_dqblk *fdq)
1646 {
1647         struct gfs2_sbd *sdp = sb->s_fs_info;
1648         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1649         struct gfs2_quota_data *qd;
1650         struct gfs2_holder q_gh, i_gh;
1651         unsigned int data_blocks, ind_blocks;
1652         unsigned int blocks = 0;
1653         int alloc_required;
1654         loff_t offset;
1655         int error;
1656
1657         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1658                 return -ESRCH; /* Crazy XFS error code */
1659
1660         if ((qid.type != USRQUOTA) &&
1661             (qid.type != GRPQUOTA))
1662                 return -EINVAL;
1663
1664         if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1665                 return -EINVAL;
1666
1667         error = qd_get(sdp, qid, &qd);
1668         if (error)
1669                 return error;
1670
1671         error = gfs2_qa_get(ip);
1672         if (error)
1673                 goto out_put;
1674
1675         inode_lock(&ip->i_inode);
1676         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1677         if (error)
1678                 goto out_unlockput;
1679         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1680         if (error)
1681                 goto out_q;
1682
1683         /* Check for existing entry, if none then alloc new blocks */
1684         error = update_qd(sdp, qd);
1685         if (error)
1686                 goto out_i;
1687
1688         /* If nothing has changed, this is a no-op */
1689         if ((fdq->d_fieldmask & QC_SPC_SOFT) &&
1690             ((fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1691                 fdq->d_fieldmask ^= QC_SPC_SOFT;
1692
1693         if ((fdq->d_fieldmask & QC_SPC_HARD) &&
1694             ((fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1695                 fdq->d_fieldmask ^= QC_SPC_HARD;
1696
1697         if ((fdq->d_fieldmask & QC_SPACE) &&
1698             ((fdq->d_space >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1699                 fdq->d_fieldmask ^= QC_SPACE;
1700
1701         if (fdq->d_fieldmask == 0)
1702                 goto out_i;
1703
1704         offset = qd2offset(qd);
1705         alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1706         if (gfs2_is_stuffed(ip))
1707                 alloc_required = 1;
1708         if (alloc_required) {
1709                 struct gfs2_alloc_parms ap = { .aflags = 0, };
1710                 gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1711                                        &data_blocks, &ind_blocks);
1712                 blocks = 1 + data_blocks + ind_blocks;
1713                 ap.target = blocks;
1714                 error = gfs2_inplace_reserve(ip, &ap);
1715                 if (error)
1716                         goto out_i;
1717                 blocks += gfs2_rg_blocks(ip, blocks);
1718         }
1719
1720         /* Some quotas span block boundaries and can update two blocks,
1721            adding an extra block to the transaction to handle such quotas */
1722         error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1723         if (error)
1724                 goto out_release;
1725
1726         /* Apply changes */
1727         error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1728         if (!error)
1729                 clear_bit(QDF_QMSG_QUIET, &qd->qd_flags);
1730
1731         gfs2_trans_end(sdp);
1732 out_release:
1733         if (alloc_required)
1734                 gfs2_inplace_release(ip);
1735 out_i:
1736         gfs2_glock_dq_uninit(&i_gh);
1737 out_q:
1738         gfs2_glock_dq_uninit(&q_gh);
1739 out_unlockput:
1740         gfs2_qa_put(ip);
1741         inode_unlock(&ip->i_inode);
1742 out_put:
1743         qd_put(qd);
1744         return error;
1745 }
1746
1747 const struct quotactl_ops gfs2_quotactl_ops = {
1748         .quota_sync     = gfs2_quota_sync,
1749         .get_state      = gfs2_quota_get_state,
1750         .get_dqblk      = gfs2_get_dqblk,
1751         .set_dqblk      = gfs2_set_dqblk,
1752 };
1753
1754 void __init gfs2_quota_hash_init(void)
1755 {
1756         unsigned i;
1757
1758         for(i = 0; i < GFS2_QD_HASH_SIZE; i++)
1759                 INIT_HLIST_BL_HEAD(&qd_hash_table[i]);
1760 }