Linux-libre 5.4.48-gnu
[librecmc/linux-libre.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_entry(list->next, 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 gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
369         unsigned int block, offset;
370         struct buffer_head *bh;
371         int error;
372         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
373
374         mutex_lock(&sdp->sd_quota_mutex);
375
376         if (qd->qd_bh_count++) {
377                 mutex_unlock(&sdp->sd_quota_mutex);
378                 return 0;
379         }
380
381         block = qd->qd_slot / sdp->sd_qc_per_block;
382         offset = qd->qd_slot % sdp->sd_qc_per_block;
383
384         bh_map.b_size = BIT(ip->i_inode.i_blkbits);
385         error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
386         if (error)
387                 goto fail;
388         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, 0, &bh);
389         if (error)
390                 goto fail;
391         error = -EIO;
392         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
393                 goto fail_brelse;
394
395         qd->qd_bh = bh;
396         qd->qd_bh_qc = (struct gfs2_quota_change *)
397                 (bh->b_data + sizeof(struct gfs2_meta_header) +
398                  offset * sizeof(struct gfs2_quota_change));
399
400         mutex_unlock(&sdp->sd_quota_mutex);
401
402         return 0;
403
404 fail_brelse:
405         brelse(bh);
406 fail:
407         qd->qd_bh_count--;
408         mutex_unlock(&sdp->sd_quota_mutex);
409         return error;
410 }
411
412 static void bh_put(struct gfs2_quota_data *qd)
413 {
414         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
415
416         mutex_lock(&sdp->sd_quota_mutex);
417         gfs2_assert(sdp, qd->qd_bh_count);
418         if (!--qd->qd_bh_count) {
419                 brelse(qd->qd_bh);
420                 qd->qd_bh = NULL;
421                 qd->qd_bh_qc = NULL;
422         }
423         mutex_unlock(&sdp->sd_quota_mutex);
424 }
425
426 static int qd_check_sync(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd,
427                          u64 *sync_gen)
428 {
429         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
430             !test_bit(QDF_CHANGE, &qd->qd_flags) ||
431             (sync_gen && (qd->qd_sync_gen >= *sync_gen)))
432                 return 0;
433
434         if (!lockref_get_not_dead(&qd->qd_lockref))
435                 return 0;
436
437         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
438         set_bit(QDF_LOCKED, &qd->qd_flags);
439         qd->qd_change_sync = qd->qd_change;
440         slot_hold(qd);
441         return 1;
442 }
443
444 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
445 {
446         struct gfs2_quota_data *qd = NULL;
447         int error;
448         int found = 0;
449
450         *qdp = NULL;
451
452         if (sb_rdonly(sdp->sd_vfs))
453                 return 0;
454
455         spin_lock(&qd_lock);
456
457         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
458                 found = qd_check_sync(sdp, qd, &sdp->sd_quota_sync_gen);
459                 if (found)
460                         break;
461         }
462
463         if (!found)
464                 qd = NULL;
465
466         spin_unlock(&qd_lock);
467
468         if (qd) {
469                 gfs2_assert_warn(sdp, qd->qd_change_sync);
470                 error = bh_get(qd);
471                 if (error) {
472                         clear_bit(QDF_LOCKED, &qd->qd_flags);
473                         slot_put(qd);
474                         qd_put(qd);
475                         return error;
476                 }
477         }
478
479         *qdp = qd;
480
481         return 0;
482 }
483
484 static void qd_unlock(struct gfs2_quota_data *qd)
485 {
486         gfs2_assert_warn(qd->qd_gl->gl_name.ln_sbd,
487                          test_bit(QDF_LOCKED, &qd->qd_flags));
488         clear_bit(QDF_LOCKED, &qd->qd_flags);
489         bh_put(qd);
490         slot_put(qd);
491         qd_put(qd);
492 }
493
494 static int qdsb_get(struct gfs2_sbd *sdp, struct kqid qid,
495                     struct gfs2_quota_data **qdp)
496 {
497         int error;
498
499         error = qd_get(sdp, qid, qdp);
500         if (error)
501                 return error;
502
503         error = slot_get(*qdp);
504         if (error)
505                 goto fail;
506
507         error = bh_get(*qdp);
508         if (error)
509                 goto fail_slot;
510
511         return 0;
512
513 fail_slot:
514         slot_put(*qdp);
515 fail:
516         qd_put(*qdp);
517         return error;
518 }
519
520 static void qdsb_put(struct gfs2_quota_data *qd)
521 {
522         bh_put(qd);
523         slot_put(qd);
524         qd_put(qd);
525 }
526
527 /**
528  * gfs2_qa_alloc - make sure we have a quota allocations data structure,
529  *                 if necessary
530  * @ip: the inode for this reservation
531  */
532 int gfs2_qa_alloc(struct gfs2_inode *ip)
533 {
534         int error = 0;
535         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
536
537         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
538                 return 0;
539
540         down_write(&ip->i_rw_mutex);
541         if (ip->i_qadata == NULL) {
542                 ip->i_qadata = kmem_cache_zalloc(gfs2_qadata_cachep, GFP_NOFS);
543                 if (!ip->i_qadata)
544                         error = -ENOMEM;
545         }
546         up_write(&ip->i_rw_mutex);
547         return error;
548 }
549
550 void gfs2_qa_delete(struct gfs2_inode *ip, atomic_t *wcount)
551 {
552         down_write(&ip->i_rw_mutex);
553         if (ip->i_qadata && ((wcount == NULL) || (atomic_read(wcount) <= 1))) {
554                 kmem_cache_free(gfs2_qadata_cachep, ip->i_qadata);
555                 ip->i_qadata = NULL;
556         }
557         up_write(&ip->i_rw_mutex);
558 }
559
560 int gfs2_quota_hold(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
561 {
562         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
563         struct gfs2_quota_data **qd;
564         int error;
565
566         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
567                 return 0;
568
569         if (ip->i_qadata == NULL) {
570                 error = gfs2_rsqa_alloc(ip);
571                 if (error)
572                         return error;
573         }
574
575         qd = ip->i_qadata->qa_qd;
576
577         if (gfs2_assert_warn(sdp, !ip->i_qadata->qa_qd_num) ||
578             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
579                 return -EIO;
580
581         error = qdsb_get(sdp, make_kqid_uid(ip->i_inode.i_uid), qd);
582         if (error)
583                 goto out;
584         ip->i_qadata->qa_qd_num++;
585         qd++;
586
587         error = qdsb_get(sdp, make_kqid_gid(ip->i_inode.i_gid), qd);
588         if (error)
589                 goto out;
590         ip->i_qadata->qa_qd_num++;
591         qd++;
592
593         if (!uid_eq(uid, NO_UID_QUOTA_CHANGE) &&
594             !uid_eq(uid, ip->i_inode.i_uid)) {
595                 error = qdsb_get(sdp, make_kqid_uid(uid), qd);
596                 if (error)
597                         goto out;
598                 ip->i_qadata->qa_qd_num++;
599                 qd++;
600         }
601
602         if (!gid_eq(gid, NO_GID_QUOTA_CHANGE) &&
603             !gid_eq(gid, ip->i_inode.i_gid)) {
604                 error = qdsb_get(sdp, make_kqid_gid(gid), qd);
605                 if (error)
606                         goto out;
607                 ip->i_qadata->qa_qd_num++;
608                 qd++;
609         }
610
611 out:
612         if (error)
613                 gfs2_quota_unhold(ip);
614         return error;
615 }
616
617 void gfs2_quota_unhold(struct gfs2_inode *ip)
618 {
619         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
620         u32 x;
621
622         if (ip->i_qadata == NULL)
623                 return;
624         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
625
626         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
627                 qdsb_put(ip->i_qadata->qa_qd[x]);
628                 ip->i_qadata->qa_qd[x] = NULL;
629         }
630         ip->i_qadata->qa_qd_num = 0;
631 }
632
633 static int sort_qd(const void *a, const void *b)
634 {
635         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
636         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
637
638         if (qid_lt(qd_a->qd_id, qd_b->qd_id))
639                 return -1;
640         if (qid_lt(qd_b->qd_id, qd_a->qd_id))
641                 return 1;
642         return 0;
643 }
644
645 static void do_qc(struct gfs2_quota_data *qd, s64 change)
646 {
647         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
648         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
649         struct gfs2_quota_change *qc = qd->qd_bh_qc;
650         s64 x;
651
652         mutex_lock(&sdp->sd_quota_mutex);
653         gfs2_trans_add_meta(ip->i_gl, qd->qd_bh);
654
655         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
656                 qc->qc_change = 0;
657                 qc->qc_flags = 0;
658                 if (qd->qd_id.type == USRQUOTA)
659                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
660                 qc->qc_id = cpu_to_be32(from_kqid(&init_user_ns, qd->qd_id));
661         }
662
663         x = be64_to_cpu(qc->qc_change) + change;
664         qc->qc_change = cpu_to_be64(x);
665
666         spin_lock(&qd_lock);
667         qd->qd_change = x;
668         spin_unlock(&qd_lock);
669
670         if (!x) {
671                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
672                 clear_bit(QDF_CHANGE, &qd->qd_flags);
673                 qc->qc_flags = 0;
674                 qc->qc_id = 0;
675                 slot_put(qd);
676                 qd_put(qd);
677         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
678                 qd_hold(qd);
679                 slot_hold(qd);
680         }
681
682         if (change < 0) /* Reset quiet flag if we freed some blocks */
683                 clear_bit(QDF_QMSG_QUIET, &qd->qd_flags);
684         mutex_unlock(&sdp->sd_quota_mutex);
685 }
686
687 static int gfs2_write_buf_to_page(struct gfs2_inode *ip, unsigned long index,
688                                   unsigned off, void *buf, unsigned bytes)
689 {
690         struct inode *inode = &ip->i_inode;
691         struct gfs2_sbd *sdp = GFS2_SB(inode);
692         struct address_space *mapping = inode->i_mapping;
693         struct page *page;
694         struct buffer_head *bh;
695         void *kaddr;
696         u64 blk;
697         unsigned bsize = sdp->sd_sb.sb_bsize, bnum = 0, boff = 0;
698         unsigned to_write = bytes, pg_off = off;
699         int done = 0;
700
701         blk = index << (PAGE_SHIFT - sdp->sd_sb.sb_bsize_shift);
702         boff = off % bsize;
703
704         page = find_or_create_page(mapping, index, GFP_NOFS);
705         if (!page)
706                 return -ENOMEM;
707         if (!page_has_buffers(page))
708                 create_empty_buffers(page, bsize, 0);
709
710         bh = page_buffers(page);
711         while (!done) {
712                 /* Find the beginning block within the page */
713                 if (pg_off >= ((bnum * bsize) + bsize)) {
714                         bh = bh->b_this_page;
715                         bnum++;
716                         blk++;
717                         continue;
718                 }
719                 if (!buffer_mapped(bh)) {
720                         gfs2_block_map(inode, blk, bh, 1);
721                         if (!buffer_mapped(bh))
722                                 goto unlock_out;
723                         /* If it's a newly allocated disk block, zero it */
724                         if (buffer_new(bh))
725                                 zero_user(page, bnum * bsize, bh->b_size);
726                 }
727                 if (PageUptodate(page))
728                         set_buffer_uptodate(bh);
729                 if (!buffer_uptodate(bh)) {
730                         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &bh);
731                         wait_on_buffer(bh);
732                         if (!buffer_uptodate(bh))
733                                 goto unlock_out;
734                 }
735                 if (gfs2_is_jdata(ip))
736                         gfs2_trans_add_data(ip->i_gl, bh);
737                 else
738                         gfs2_ordered_add_inode(ip);
739
740                 /* If we need to write to the next block as well */
741                 if (to_write > (bsize - boff)) {
742                         pg_off += (bsize - boff);
743                         to_write -= (bsize - boff);
744                         boff = pg_off % bsize;
745                         continue;
746                 }
747                 done = 1;
748         }
749
750         /* Write to the page, now that we have setup the buffer(s) */
751         kaddr = kmap_atomic(page);
752         memcpy(kaddr + off, buf, bytes);
753         flush_dcache_page(page);
754         kunmap_atomic(kaddr);
755         unlock_page(page);
756         put_page(page);
757
758         return 0;
759
760 unlock_out:
761         unlock_page(page);
762         put_page(page);
763         return -EIO;
764 }
765
766 static int gfs2_write_disk_quota(struct gfs2_inode *ip, struct gfs2_quota *qp,
767                                  loff_t loc)
768 {
769         unsigned long pg_beg;
770         unsigned pg_off, nbytes, overflow = 0;
771         int pg_oflow = 0, error;
772         void *ptr;
773
774         nbytes = sizeof(struct gfs2_quota);
775
776         pg_beg = loc >> PAGE_SHIFT;
777         pg_off = offset_in_page(loc);
778
779         /* If the quota straddles a page boundary, split the write in two */
780         if ((pg_off + nbytes) > PAGE_SIZE) {
781                 pg_oflow = 1;
782                 overflow = (pg_off + nbytes) - PAGE_SIZE;
783         }
784
785         ptr = qp;
786         error = gfs2_write_buf_to_page(ip, pg_beg, pg_off, ptr,
787                                        nbytes - overflow);
788         /* If there's an overflow, write the remaining bytes to the next page */
789         if (!error && pg_oflow)
790                 error = gfs2_write_buf_to_page(ip, pg_beg + 1, 0,
791                                                ptr + nbytes - overflow,
792                                                overflow);
793         return error;
794 }
795
796 /**
797  * gfs2_adjust_quota - adjust record of current block usage
798  * @ip: The quota inode
799  * @loc: Offset of the entry in the quota file
800  * @change: The amount of usage change to record
801  * @qd: The quota data
802  * @fdq: The updated limits to record
803  *
804  * This function was mostly borrowed from gfs2_block_truncate_page which was
805  * in turn mostly borrowed from ext3
806  *
807  * Returns: 0 or -ve on error
808  */
809
810 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
811                              s64 change, struct gfs2_quota_data *qd,
812                              struct qc_dqblk *fdq)
813 {
814         struct inode *inode = &ip->i_inode;
815         struct gfs2_sbd *sdp = GFS2_SB(inode);
816         struct gfs2_quota q;
817         int err;
818         u64 size;
819
820         if (gfs2_is_stuffed(ip)) {
821                 err = gfs2_unstuff_dinode(ip, NULL);
822                 if (err)
823                         return err;
824         }
825
826         memset(&q, 0, sizeof(struct gfs2_quota));
827         err = gfs2_internal_read(ip, (char *)&q, &loc, sizeof(q));
828         if (err < 0)
829                 return err;
830
831         loc -= sizeof(q); /* gfs2_internal_read would've advanced the loc ptr */
832         err = -EIO;
833         be64_add_cpu(&q.qu_value, change);
834         if (((s64)be64_to_cpu(q.qu_value)) < 0)
835                 q.qu_value = 0; /* Never go negative on quota usage */
836         qd->qd_qb.qb_value = q.qu_value;
837         if (fdq) {
838                 if (fdq->d_fieldmask & QC_SPC_SOFT) {
839                         q.qu_warn = cpu_to_be64(fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift);
840                         qd->qd_qb.qb_warn = q.qu_warn;
841                 }
842                 if (fdq->d_fieldmask & QC_SPC_HARD) {
843                         q.qu_limit = cpu_to_be64(fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift);
844                         qd->qd_qb.qb_limit = q.qu_limit;
845                 }
846                 if (fdq->d_fieldmask & QC_SPACE) {
847                         q.qu_value = cpu_to_be64(fdq->d_space >> sdp->sd_sb.sb_bsize_shift);
848                         qd->qd_qb.qb_value = q.qu_value;
849                 }
850         }
851
852         err = gfs2_write_disk_quota(ip, &q, loc);
853         if (!err) {
854                 size = loc + sizeof(struct gfs2_quota);
855                 if (size > inode->i_size)
856                         i_size_write(inode, size);
857                 inode->i_mtime = inode->i_atime = current_time(inode);
858                 mark_inode_dirty(inode);
859                 set_bit(QDF_REFRESH, &qd->qd_flags);
860         }
861
862         return err;
863 }
864
865 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
866 {
867         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_name.ln_sbd;
868         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
869         struct gfs2_alloc_parms ap = { .aflags = 0, };
870         unsigned int data_blocks, ind_blocks;
871         struct gfs2_holder *ghs, i_gh;
872         unsigned int qx, x;
873         struct gfs2_quota_data *qd;
874         unsigned reserved;
875         loff_t offset;
876         unsigned int nalloc = 0, blocks;
877         int error;
878
879         error = gfs2_rsqa_alloc(ip);
880         if (error)
881                 return error;
882
883         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
884                               &data_blocks, &ind_blocks);
885
886         ghs = kmalloc_array(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
887         if (!ghs)
888                 return -ENOMEM;
889
890         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
891         inode_lock(&ip->i_inode);
892         for (qx = 0; qx < num_qd; qx++) {
893                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
894                                            GL_NOCACHE, &ghs[qx]);
895                 if (error)
896                         goto out;
897         }
898
899         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
900         if (error)
901                 goto out;
902
903         for (x = 0; x < num_qd; x++) {
904                 offset = qd2offset(qda[x]);
905                 if (gfs2_write_alloc_required(ip, offset,
906                                               sizeof(struct gfs2_quota)))
907                         nalloc++;
908         }
909
910         /* 
911          * 1 blk for unstuffing inode if stuffed. We add this extra
912          * block to the reservation unconditionally. If the inode
913          * doesn't need unstuffing, the block will be released to the 
914          * rgrp since it won't be allocated during the transaction
915          */
916         /* +3 in the end for unstuffing block, inode size update block
917          * and another block in case quota straddles page boundary and 
918          * two blocks need to be updated instead of 1 */
919         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
920
921         reserved = 1 + (nalloc * (data_blocks + ind_blocks));
922         ap.target = reserved;
923         error = gfs2_inplace_reserve(ip, &ap);
924         if (error)
925                 goto out_alloc;
926
927         if (nalloc)
928                 blocks += gfs2_rg_blocks(ip, reserved) + nalloc * ind_blocks + RES_STATFS;
929
930         error = gfs2_trans_begin(sdp, blocks, 0);
931         if (error)
932                 goto out_ipres;
933
934         for (x = 0; x < num_qd; x++) {
935                 qd = qda[x];
936                 offset = qd2offset(qd);
937                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
938                 if (error)
939                         goto out_end_trans;
940
941                 do_qc(qd, -qd->qd_change_sync);
942                 set_bit(QDF_REFRESH, &qd->qd_flags);
943         }
944
945         error = 0;
946
947 out_end_trans:
948         gfs2_trans_end(sdp);
949 out_ipres:
950         gfs2_inplace_release(ip);
951 out_alloc:
952         gfs2_glock_dq_uninit(&i_gh);
953 out:
954         while (qx--)
955                 gfs2_glock_dq_uninit(&ghs[qx]);
956         inode_unlock(&ip->i_inode);
957         kfree(ghs);
958         gfs2_log_flush(ip->i_gl->gl_name.ln_sbd, ip->i_gl,
959                        GFS2_LOG_HEAD_FLUSH_NORMAL | GFS2_LFC_DO_SYNC);
960         return error;
961 }
962
963 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
964 {
965         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
966         struct gfs2_quota q;
967         struct gfs2_quota_lvb *qlvb;
968         loff_t pos;
969         int error;
970
971         memset(&q, 0, sizeof(struct gfs2_quota));
972         pos = qd2offset(qd);
973         error = gfs2_internal_read(ip, (char *)&q, &pos, sizeof(q));
974         if (error < 0)
975                 return error;
976
977         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
978         qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
979         qlvb->__pad = 0;
980         qlvb->qb_limit = q.qu_limit;
981         qlvb->qb_warn = q.qu_warn;
982         qlvb->qb_value = q.qu_value;
983         qd->qd_qb = *qlvb;
984
985         return 0;
986 }
987
988 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
989                     struct gfs2_holder *q_gh)
990 {
991         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
992         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
993         struct gfs2_holder i_gh;
994         int error;
995
996 restart:
997         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
998         if (error)
999                 return error;
1000
1001         if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
1002                 force_refresh = FORCE;
1003
1004         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1005
1006         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
1007                 gfs2_glock_dq_uninit(q_gh);
1008                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
1009                                            GL_NOCACHE, q_gh);
1010                 if (error)
1011                         return error;
1012
1013                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
1014                 if (error)
1015                         goto fail;
1016
1017                 error = update_qd(sdp, qd);
1018                 if (error)
1019                         goto fail_gunlock;
1020
1021                 gfs2_glock_dq_uninit(&i_gh);
1022                 gfs2_glock_dq_uninit(q_gh);
1023                 force_refresh = 0;
1024                 goto restart;
1025         }
1026
1027         return 0;
1028
1029 fail_gunlock:
1030         gfs2_glock_dq_uninit(&i_gh);
1031 fail:
1032         gfs2_glock_dq_uninit(q_gh);
1033         return error;
1034 }
1035
1036 int gfs2_quota_lock(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
1037 {
1038         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1039         struct gfs2_quota_data *qd;
1040         u32 x;
1041         int error = 0;
1042
1043         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1044                 return 0;
1045
1046         error = gfs2_quota_hold(ip, uid, gid);
1047         if (error)
1048                 return error;
1049
1050         sort(ip->i_qadata->qa_qd, ip->i_qadata->qa_qd_num,
1051              sizeof(struct gfs2_quota_data *), sort_qd, NULL);
1052
1053         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1054                 qd = ip->i_qadata->qa_qd[x];
1055                 error = do_glock(qd, NO_FORCE, &ip->i_qadata->qa_qd_ghs[x]);
1056                 if (error)
1057                         break;
1058         }
1059
1060         if (!error)
1061                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
1062         else {
1063                 while (x--)
1064                         gfs2_glock_dq_uninit(&ip->i_qadata->qa_qd_ghs[x]);
1065                 gfs2_quota_unhold(ip);
1066         }
1067
1068         return error;
1069 }
1070
1071 static int need_sync(struct gfs2_quota_data *qd)
1072 {
1073         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1074         struct gfs2_tune *gt = &sdp->sd_tune;
1075         s64 value;
1076         unsigned int num, den;
1077         int do_sync = 1;
1078
1079         if (!qd->qd_qb.qb_limit)
1080                 return 0;
1081
1082         spin_lock(&qd_lock);
1083         value = qd->qd_change;
1084         spin_unlock(&qd_lock);
1085
1086         spin_lock(&gt->gt_spin);
1087         num = gt->gt_quota_scale_num;
1088         den = gt->gt_quota_scale_den;
1089         spin_unlock(&gt->gt_spin);
1090
1091         if (value < 0)
1092                 do_sync = 0;
1093         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
1094                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1095                 do_sync = 0;
1096         else {
1097                 value *= gfs2_jindex_size(sdp) * num;
1098                 value = div_s64(value, den);
1099                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
1100                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1101                         do_sync = 0;
1102         }
1103
1104         return do_sync;
1105 }
1106
1107 void gfs2_quota_unlock(struct gfs2_inode *ip)
1108 {
1109         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1110         struct gfs2_quota_data *qda[4];
1111         unsigned int count = 0;
1112         u32 x;
1113         int found;
1114
1115         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1116                 goto out;
1117
1118         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1119                 struct gfs2_quota_data *qd;
1120                 int sync;
1121
1122                 qd = ip->i_qadata->qa_qd[x];
1123                 sync = need_sync(qd);
1124
1125                 gfs2_glock_dq_uninit(&ip->i_qadata->qa_qd_ghs[x]);
1126                 if (!sync)
1127                         continue;
1128
1129                 spin_lock(&qd_lock);
1130                 found = qd_check_sync(sdp, qd, NULL);
1131                 spin_unlock(&qd_lock);
1132
1133                 if (!found)
1134                         continue;
1135
1136                 gfs2_assert_warn(sdp, qd->qd_change_sync);
1137                 if (bh_get(qd)) {
1138                         clear_bit(QDF_LOCKED, &qd->qd_flags);
1139                         slot_put(qd);
1140                         qd_put(qd);
1141                         continue;
1142                 }
1143
1144                 qda[count++] = qd;
1145         }
1146
1147         if (count) {
1148                 do_sync(count, qda);
1149                 for (x = 0; x < count; x++)
1150                         qd_unlock(qda[x]);
1151         }
1152
1153 out:
1154         gfs2_quota_unhold(ip);
1155 }
1156
1157 #define MAX_LINE 256
1158
1159 static int print_message(struct gfs2_quota_data *qd, char *type)
1160 {
1161         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1162
1163         fs_info(sdp, "quota %s for %s %u\n",
1164                 type,
1165                 (qd->qd_id.type == USRQUOTA) ? "user" : "group",
1166                 from_kqid(&init_user_ns, qd->qd_id));
1167
1168         return 0;
1169 }
1170
1171 /**
1172  * gfs2_quota_check - check if allocating new blocks will exceed quota
1173  * @ip:  The inode for which this check is being performed
1174  * @uid: The uid to check against
1175  * @gid: The gid to check against
1176  * @ap:  The allocation parameters. ap->target contains the requested
1177  *       blocks. ap->min_target, if set, contains the minimum blks
1178  *       requested.
1179  *
1180  * Returns: 0 on success.
1181  *                  min_req = ap->min_target ? ap->min_target : ap->target;
1182  *                  quota must allow at least min_req blks for success and
1183  *                  ap->allowed is set to the number of blocks allowed
1184  *
1185  *          -EDQUOT otherwise, quota violation. ap->allowed is set to number
1186  *                  of blocks available.
1187  */
1188 int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid,
1189                      struct gfs2_alloc_parms *ap)
1190 {
1191         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1192         struct gfs2_quota_data *qd;
1193         s64 value, warn, limit;
1194         u32 x;
1195         int error = 0;
1196
1197         ap->allowed = UINT_MAX; /* Assume we are permitted a whole lot */
1198         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1199                 return 0;
1200
1201         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1202                 return 0;
1203
1204         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1205                 qd = ip->i_qadata->qa_qd[x];
1206
1207                 if (!(qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1208                       qid_eq(qd->qd_id, make_kqid_gid(gid))))
1209                         continue;
1210
1211                 warn = (s64)be64_to_cpu(qd->qd_qb.qb_warn);
1212                 limit = (s64)be64_to_cpu(qd->qd_qb.qb_limit);
1213                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1214                 spin_lock(&qd_lock);
1215                 value += qd->qd_change;
1216                 spin_unlock(&qd_lock);
1217
1218                 if (limit > 0 && (limit - value) < ap->allowed)
1219                         ap->allowed = limit - value;
1220                 /* If we can't meet the target */
1221                 if (limit && limit < (value + (s64)ap->target)) {
1222                         /* If no min_target specified or we don't meet
1223                          * min_target, return -EDQUOT */
1224                         if (!ap->min_target || ap->min_target > ap->allowed) {
1225                                 if (!test_and_set_bit(QDF_QMSG_QUIET,
1226                                                       &qd->qd_flags)) {
1227                                         print_message(qd, "exceeded");
1228                                         quota_send_warning(qd->qd_id,
1229                                                            sdp->sd_vfs->s_dev,
1230                                                            QUOTA_NL_BHARDWARN);
1231                                 }
1232                                 error = -EDQUOT;
1233                                 break;
1234                         }
1235                 } else if (warn && warn < value &&
1236                            time_after_eq(jiffies, qd->qd_last_warn +
1237                                          gfs2_tune_get(sdp, gt_quota_warn_period)
1238                                          * HZ)) {
1239                         quota_send_warning(qd->qd_id,
1240                                            sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1241                         error = print_message(qd, "warning");
1242                         qd->qd_last_warn = jiffies;
1243                 }
1244         }
1245         return error;
1246 }
1247
1248 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1249                        kuid_t uid, kgid_t gid)
1250 {
1251         struct gfs2_quota_data *qd;
1252         u32 x;
1253         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1254
1255         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON ||
1256             gfs2_assert_warn(sdp, change))
1257                 return;
1258         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1259                 return;
1260
1261         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1262                 qd = ip->i_qadata->qa_qd[x];
1263
1264                 if (qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1265                     qid_eq(qd->qd_id, make_kqid_gid(gid))) {
1266                         do_qc(qd, change);
1267                 }
1268         }
1269 }
1270
1271 int gfs2_quota_sync(struct super_block *sb, int type)
1272 {
1273         struct gfs2_sbd *sdp = sb->s_fs_info;
1274         struct gfs2_quota_data **qda;
1275         unsigned int max_qd = PAGE_SIZE/sizeof(struct gfs2_holder);
1276         unsigned int num_qd;
1277         unsigned int x;
1278         int error = 0;
1279
1280         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1281         if (!qda)
1282                 return -ENOMEM;
1283
1284         mutex_lock(&sdp->sd_quota_sync_mutex);
1285         sdp->sd_quota_sync_gen++;
1286
1287         do {
1288                 num_qd = 0;
1289
1290                 for (;;) {
1291                         error = qd_fish(sdp, qda + num_qd);
1292                         if (error || !qda[num_qd])
1293                                 break;
1294                         if (++num_qd == max_qd)
1295                                 break;
1296                 }
1297
1298                 if (num_qd) {
1299                         if (!error)
1300                                 error = do_sync(num_qd, qda);
1301                         if (!error)
1302                                 for (x = 0; x < num_qd; x++)
1303                                         qda[x]->qd_sync_gen =
1304                                                 sdp->sd_quota_sync_gen;
1305
1306                         for (x = 0; x < num_qd; x++)
1307                                 qd_unlock(qda[x]);
1308                 }
1309         } while (!error && num_qd == max_qd);
1310
1311         mutex_unlock(&sdp->sd_quota_sync_mutex);
1312         kfree(qda);
1313
1314         return error;
1315 }
1316
1317 int gfs2_quota_refresh(struct gfs2_sbd *sdp, struct kqid qid)
1318 {
1319         struct gfs2_quota_data *qd;
1320         struct gfs2_holder q_gh;
1321         int error;
1322
1323         error = qd_get(sdp, qid, &qd);
1324         if (error)
1325                 return error;
1326
1327         error = do_glock(qd, FORCE, &q_gh);
1328         if (!error)
1329                 gfs2_glock_dq_uninit(&q_gh);
1330
1331         qd_put(qd);
1332         return error;
1333 }
1334
1335 int gfs2_quota_init(struct gfs2_sbd *sdp)
1336 {
1337         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1338         u64 size = i_size_read(sdp->sd_qc_inode);
1339         unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1340         unsigned int x, slot = 0;
1341         unsigned int found = 0;
1342         unsigned int hash;
1343         unsigned int bm_size;
1344         u64 dblock;
1345         u32 extlen = 0;
1346         int error;
1347
1348         if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1349                 return -EIO;
1350
1351         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1352         bm_size = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * sizeof(unsigned long));
1353         bm_size *= sizeof(unsigned long);
1354         error = -ENOMEM;
1355         sdp->sd_quota_bitmap = kzalloc(bm_size, GFP_NOFS | __GFP_NOWARN);
1356         if (sdp->sd_quota_bitmap == NULL)
1357                 sdp->sd_quota_bitmap = __vmalloc(bm_size, GFP_NOFS |
1358                                                  __GFP_ZERO, PAGE_KERNEL);
1359         if (!sdp->sd_quota_bitmap)
1360                 return error;
1361
1362         for (x = 0; x < blocks; x++) {
1363                 struct buffer_head *bh;
1364                 const struct gfs2_quota_change *qc;
1365                 unsigned int y;
1366
1367                 if (!extlen) {
1368                         int new = 0;
1369                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1370                         if (error)
1371                                 goto fail;
1372                 }
1373                 error = -EIO;
1374                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1375                 if (!bh)
1376                         goto fail;
1377                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1378                         brelse(bh);
1379                         goto fail;
1380                 }
1381
1382                 qc = (const struct gfs2_quota_change *)(bh->b_data + sizeof(struct gfs2_meta_header));
1383                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1384                      y++, slot++) {
1385                         struct gfs2_quota_data *qd;
1386                         s64 qc_change = be64_to_cpu(qc->qc_change);
1387                         u32 qc_flags = be32_to_cpu(qc->qc_flags);
1388                         enum quota_type qtype = (qc_flags & GFS2_QCF_USER) ?
1389                                                 USRQUOTA : GRPQUOTA;
1390                         struct kqid qc_id = make_kqid(&init_user_ns, qtype,
1391                                                       be32_to_cpu(qc->qc_id));
1392                         qc++;
1393                         if (!qc_change)
1394                                 continue;
1395
1396                         hash = gfs2_qd_hash(sdp, qc_id);
1397                         qd = qd_alloc(hash, sdp, qc_id);
1398                         if (qd == NULL) {
1399                                 brelse(bh);
1400                                 goto fail;
1401                         }
1402
1403                         set_bit(QDF_CHANGE, &qd->qd_flags);
1404                         qd->qd_change = qc_change;
1405                         qd->qd_slot = slot;
1406                         qd->qd_slot_count = 1;
1407
1408                         spin_lock(&qd_lock);
1409                         BUG_ON(test_and_set_bit(slot, sdp->sd_quota_bitmap));
1410                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1411                         atomic_inc(&sdp->sd_quota_count);
1412                         spin_unlock(&qd_lock);
1413
1414                         spin_lock_bucket(hash);
1415                         hlist_bl_add_head_rcu(&qd->qd_hlist, &qd_hash_table[hash]);
1416                         spin_unlock_bucket(hash);
1417
1418                         found++;
1419                 }
1420
1421                 brelse(bh);
1422                 dblock++;
1423                 extlen--;
1424         }
1425
1426         if (found)
1427                 fs_info(sdp, "found %u quota changes\n", found);
1428
1429         return 0;
1430
1431 fail:
1432         gfs2_quota_cleanup(sdp);
1433         return error;
1434 }
1435
1436 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1437 {
1438         struct list_head *head = &sdp->sd_quota_list;
1439         struct gfs2_quota_data *qd;
1440
1441         spin_lock(&qd_lock);
1442         while (!list_empty(head)) {
1443                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1444
1445                 list_del(&qd->qd_list);
1446
1447                 /* Also remove if this qd exists in the reclaim list */
1448                 list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
1449                 atomic_dec(&sdp->sd_quota_count);
1450                 spin_unlock(&qd_lock);
1451
1452                 spin_lock_bucket(qd->qd_hash);
1453                 hlist_bl_del_rcu(&qd->qd_hlist);
1454                 spin_unlock_bucket(qd->qd_hash);
1455
1456                 gfs2_assert_warn(sdp, !qd->qd_change);
1457                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1458                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1459
1460                 gfs2_glock_put(qd->qd_gl);
1461                 call_rcu(&qd->qd_rcu, gfs2_qd_dealloc);
1462
1463                 spin_lock(&qd_lock);
1464         }
1465         spin_unlock(&qd_lock);
1466
1467         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1468
1469         kvfree(sdp->sd_quota_bitmap);
1470         sdp->sd_quota_bitmap = NULL;
1471 }
1472
1473 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1474 {
1475         if (error == 0 || error == -EROFS)
1476                 return;
1477         if (!test_bit(SDF_WITHDRAWN, &sdp->sd_flags)) {
1478                 fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1479                 sdp->sd_log_error = error;
1480                 wake_up(&sdp->sd_logd_waitq);
1481         }
1482 }
1483
1484 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1485                                int (*fxn)(struct super_block *sb, int type),
1486                                unsigned long t, unsigned long *timeo,
1487                                unsigned int *new_timeo)
1488 {
1489         if (t >= *timeo) {
1490                 int error = fxn(sdp->sd_vfs, 0);
1491                 quotad_error(sdp, msg, error);
1492                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1493         } else {
1494                 *timeo -= t;
1495         }
1496 }
1497
1498 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1499 {
1500         struct gfs2_inode *ip;
1501
1502         while(1) {
1503                 ip = NULL;
1504                 spin_lock(&sdp->sd_trunc_lock);
1505                 if (!list_empty(&sdp->sd_trunc_list)) {
1506                         ip = list_entry(sdp->sd_trunc_list.next,
1507                                         struct gfs2_inode, i_trunc_list);
1508                         list_del_init(&ip->i_trunc_list);
1509                 }
1510                 spin_unlock(&sdp->sd_trunc_lock);
1511                 if (ip == NULL)
1512                         return;
1513                 gfs2_glock_finish_truncate(ip);
1514         }
1515 }
1516
1517 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1518         if (!sdp->sd_statfs_force_sync) {
1519                 sdp->sd_statfs_force_sync = 1;
1520                 wake_up(&sdp->sd_quota_wait);
1521         }
1522 }
1523
1524
1525 /**
1526  * gfs2_quotad - Write cached quota changes into the quota file
1527  * @sdp: Pointer to GFS2 superblock
1528  *
1529  */
1530
1531 int gfs2_quotad(void *data)
1532 {
1533         struct gfs2_sbd *sdp = data;
1534         struct gfs2_tune *tune = &sdp->sd_tune;
1535         unsigned long statfs_timeo = 0;
1536         unsigned long quotad_timeo = 0;
1537         unsigned long t = 0;
1538         DEFINE_WAIT(wait);
1539         int empty;
1540
1541         while (!kthread_should_stop()) {
1542
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                 /* Check for & recover partially truncated inodes */
1559                 quotad_check_trunc_list(sdp);
1560
1561                 try_to_freeze();
1562
1563                 t = min(quotad_timeo, statfs_timeo);
1564
1565                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1566                 spin_lock(&sdp->sd_trunc_lock);
1567                 empty = list_empty(&sdp->sd_trunc_list);
1568                 spin_unlock(&sdp->sd_trunc_lock);
1569                 if (empty && !sdp->sd_statfs_force_sync)
1570                         t -= schedule_timeout(t);
1571                 else
1572                         t = 0;
1573                 finish_wait(&sdp->sd_quota_wait, &wait);
1574         }
1575
1576         return 0;
1577 }
1578
1579 static int gfs2_quota_get_state(struct super_block *sb, struct qc_state *state)
1580 {
1581         struct gfs2_sbd *sdp = sb->s_fs_info;
1582
1583         memset(state, 0, sizeof(*state));
1584
1585         switch (sdp->sd_args.ar_quota) {
1586         case GFS2_QUOTA_ON:
1587                 state->s_state[USRQUOTA].flags |= QCI_LIMITS_ENFORCED;
1588                 state->s_state[GRPQUOTA].flags |= QCI_LIMITS_ENFORCED;
1589                 /*FALLTHRU*/
1590         case GFS2_QUOTA_ACCOUNT:
1591                 state->s_state[USRQUOTA].flags |= QCI_ACCT_ENABLED |
1592                                                   QCI_SYSFILE;
1593                 state->s_state[GRPQUOTA].flags |= QCI_ACCT_ENABLED |
1594                                                   QCI_SYSFILE;
1595                 break;
1596         case GFS2_QUOTA_OFF:
1597                 break;
1598         }
1599         if (sdp->sd_quota_inode) {
1600                 state->s_state[USRQUOTA].ino =
1601                                         GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1602                 state->s_state[USRQUOTA].blocks = sdp->sd_quota_inode->i_blocks;
1603         }
1604         state->s_state[USRQUOTA].nextents = 1;  /* unsupported */
1605         state->s_state[GRPQUOTA] = state->s_state[USRQUOTA];
1606         state->s_incoredqs = list_lru_count(&gfs2_qd_lru);
1607         return 0;
1608 }
1609
1610 static int gfs2_get_dqblk(struct super_block *sb, struct kqid qid,
1611                           struct qc_dqblk *fdq)
1612 {
1613         struct gfs2_sbd *sdp = sb->s_fs_info;
1614         struct gfs2_quota_lvb *qlvb;
1615         struct gfs2_quota_data *qd;
1616         struct gfs2_holder q_gh;
1617         int error;
1618
1619         memset(fdq, 0, sizeof(*fdq));
1620
1621         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1622                 return -ESRCH; /* Crazy XFS error code */
1623
1624         if ((qid.type != USRQUOTA) &&
1625             (qid.type != GRPQUOTA))
1626                 return -EINVAL;
1627
1628         error = qd_get(sdp, qid, &qd);
1629         if (error)
1630                 return error;
1631         error = do_glock(qd, FORCE, &q_gh);
1632         if (error)
1633                 goto out;
1634
1635         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1636         fdq->d_spc_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_sb.sb_bsize_shift;
1637         fdq->d_spc_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_sb.sb_bsize_shift;
1638         fdq->d_space = be64_to_cpu(qlvb->qb_value) << sdp->sd_sb.sb_bsize_shift;
1639
1640         gfs2_glock_dq_uninit(&q_gh);
1641 out:
1642         qd_put(qd);
1643         return error;
1644 }
1645
1646 /* GFS2 only supports a subset of the XFS fields */
1647 #define GFS2_FIELDMASK (QC_SPC_SOFT|QC_SPC_HARD|QC_SPACE)
1648
1649 static int gfs2_set_dqblk(struct super_block *sb, struct kqid qid,
1650                           struct qc_dqblk *fdq)
1651 {
1652         struct gfs2_sbd *sdp = sb->s_fs_info;
1653         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1654         struct gfs2_quota_data *qd;
1655         struct gfs2_holder q_gh, i_gh;
1656         unsigned int data_blocks, ind_blocks;
1657         unsigned int blocks = 0;
1658         int alloc_required;
1659         loff_t offset;
1660         int error;
1661
1662         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1663                 return -ESRCH; /* Crazy XFS error code */
1664
1665         if ((qid.type != USRQUOTA) &&
1666             (qid.type != GRPQUOTA))
1667                 return -EINVAL;
1668
1669         if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1670                 return -EINVAL;
1671
1672         error = qd_get(sdp, qid, &qd);
1673         if (error)
1674                 return error;
1675
1676         error = gfs2_rsqa_alloc(ip);
1677         if (error)
1678                 goto out_put;
1679
1680         inode_lock(&ip->i_inode);
1681         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1682         if (error)
1683                 goto out_unlockput;
1684         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1685         if (error)
1686                 goto out_q;
1687
1688         /* Check for existing entry, if none then alloc new blocks */
1689         error = update_qd(sdp, qd);
1690         if (error)
1691                 goto out_i;
1692
1693         /* If nothing has changed, this is a no-op */
1694         if ((fdq->d_fieldmask & QC_SPC_SOFT) &&
1695             ((fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1696                 fdq->d_fieldmask ^= QC_SPC_SOFT;
1697
1698         if ((fdq->d_fieldmask & QC_SPC_HARD) &&
1699             ((fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1700                 fdq->d_fieldmask ^= QC_SPC_HARD;
1701
1702         if ((fdq->d_fieldmask & QC_SPACE) &&
1703             ((fdq->d_space >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1704                 fdq->d_fieldmask ^= QC_SPACE;
1705
1706         if (fdq->d_fieldmask == 0)
1707                 goto out_i;
1708
1709         offset = qd2offset(qd);
1710         alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1711         if (gfs2_is_stuffed(ip))
1712                 alloc_required = 1;
1713         if (alloc_required) {
1714                 struct gfs2_alloc_parms ap = { .aflags = 0, };
1715                 gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1716                                        &data_blocks, &ind_blocks);
1717                 blocks = 1 + data_blocks + ind_blocks;
1718                 ap.target = blocks;
1719                 error = gfs2_inplace_reserve(ip, &ap);
1720                 if (error)
1721                         goto out_i;
1722                 blocks += gfs2_rg_blocks(ip, blocks);
1723         }
1724
1725         /* Some quotas span block boundaries and can update two blocks,
1726            adding an extra block to the transaction to handle such quotas */
1727         error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1728         if (error)
1729                 goto out_release;
1730
1731         /* Apply changes */
1732         error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1733         if (!error)
1734                 clear_bit(QDF_QMSG_QUIET, &qd->qd_flags);
1735
1736         gfs2_trans_end(sdp);
1737 out_release:
1738         if (alloc_required)
1739                 gfs2_inplace_release(ip);
1740 out_i:
1741         gfs2_glock_dq_uninit(&i_gh);
1742 out_q:
1743         gfs2_glock_dq_uninit(&q_gh);
1744 out_unlockput:
1745         inode_unlock(&ip->i_inode);
1746 out_put:
1747         qd_put(qd);
1748         return error;
1749 }
1750
1751 const struct quotactl_ops gfs2_quotactl_ops = {
1752         .quota_sync     = gfs2_quota_sync,
1753         .get_state      = gfs2_quota_get_state,
1754         .get_dqblk      = gfs2_get_dqblk,
1755         .set_dqblk      = gfs2_set_dqblk,
1756 };
1757
1758 void __init gfs2_quota_hash_init(void)
1759 {
1760         unsigned i;
1761
1762         for(i = 0; i < GFS2_QD_HASH_SIZE; i++)
1763                 INIT_HLIST_BL_HEAD(&qd_hash_table[i]);
1764 }