gfs2: move privileged user check to gfs2_quota_lock_check
[platform/kernel/linux-rpi.git] / fs / gfs2 / quota.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
4  * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
5  */
6
7 /*
8  * Quota change tags are associated with each transaction that allocates or
9  * deallocates space.  Those changes are accumulated locally to each node (in a
10  * per-node file) and then are periodically synced to the quota file.  This
11  * avoids the bottleneck of constantly touching the quota file, but introduces
12  * fuzziness in the current usage value of IDs that are being used on different
13  * nodes in the cluster simultaneously.  So, it is possible for a user on
14  * multiple nodes to overrun their quota, but that overrun is controlable.
15  * Since quota tags are part of transactions, there is no need for a quota check
16  * program to be run on node crashes or anything like that.
17  *
18  * There are couple of knobs that let the administrator manage the quota
19  * fuzziness.  "quota_quantum" sets the maximum time a quota change can be
20  * sitting on one node before being synced to the quota file.  (The default is
21  * 60 seconds.)  Another knob, "quota_scale" controls how quickly the frequency
22  * of quota file syncs increases as the user moves closer to their limit.  The
23  * more frequent the syncs, the more accurate the quota enforcement, but that
24  * means that there is more contention between the nodes for the quota file.
25  * The default value is one.  This sets the maximum theoretical quota overrun
26  * (with infinite node with infinite bandwidth) to twice the user's limit.  (In
27  * practice, the maximum overrun you see should be much less.)  A "quota_scale"
28  * number greater than one makes quota syncs more frequent and reduces the
29  * maximum overrun.  Numbers less than one (but greater than zero) make quota
30  * syncs less frequent.
31  *
32  * GFS quotas also use per-ID Lock Value Blocks (LVBs) to cache the contents of
33  * the quota file, so it is not being constantly read.
34  */
35
36 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
37
38 #include <linux/sched.h>
39 #include <linux/slab.h>
40 #include <linux/mm.h>
41 #include <linux/spinlock.h>
42 #include <linux/completion.h>
43 #include <linux/buffer_head.h>
44 #include <linux/sort.h>
45 #include <linux/fs.h>
46 #include <linux/bio.h>
47 #include <linux/gfs2_ondisk.h>
48 #include <linux/kthread.h>
49 #include <linux/freezer.h>
50 #include <linux/quota.h>
51 #include <linux/dqblk_xfs.h>
52 #include <linux/lockref.h>
53 #include <linux/list_lru.h>
54 #include <linux/rcupdate.h>
55 #include <linux/rculist_bl.h>
56 #include <linux/bit_spinlock.h>
57 #include <linux/jhash.h>
58 #include <linux/vmalloc.h>
59
60 #include "gfs2.h"
61 #include "incore.h"
62 #include "bmap.h"
63 #include "glock.h"
64 #include "glops.h"
65 #include "log.h"
66 #include "meta_io.h"
67 #include "quota.h"
68 #include "rgrp.h"
69 #include "super.h"
70 #include "trans.h"
71 #include "inode.h"
72 #include "util.h"
73
74 #define GFS2_QD_HASH_SHIFT      12
75 #define GFS2_QD_HASH_SIZE       BIT(GFS2_QD_HASH_SHIFT)
76 #define GFS2_QD_HASH_MASK       (GFS2_QD_HASH_SIZE - 1)
77
78 /* 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 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_get - make sure we have a quota allocations data structure,
529  *               if necessary
530  * @ip: the inode for this reservation
531  */
532 int gfs2_qa_get(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                         goto out;
546                 }
547         }
548         ip->i_qadata->qa_ref++;
549 out:
550         up_write(&ip->i_rw_mutex);
551         return error;
552 }
553
554 void gfs2_qa_put(struct gfs2_inode *ip)
555 {
556         down_write(&ip->i_rw_mutex);
557         if (ip->i_qadata && --ip->i_qadata->qa_ref == 0) {
558                 kmem_cache_free(gfs2_qadata_cachep, ip->i_qadata);
559                 ip->i_qadata = NULL;
560         }
561         up_write(&ip->i_rw_mutex);
562 }
563
564 int gfs2_quota_hold(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
565 {
566         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
567         struct gfs2_quota_data **qd;
568         int error;
569
570         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
571                 return 0;
572
573         error = gfs2_qa_get(ip);
574         if (error)
575                 return error;
576
577         qd = ip->i_qadata->qa_qd;
578
579         if (gfs2_assert_warn(sdp, !ip->i_qadata->qa_qd_num) ||
580             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags))) {
581                 error = -EIO;
582                 goto out;
583         }
584
585         error = qdsb_get(sdp, make_kqid_uid(ip->i_inode.i_uid), qd);
586         if (error)
587                 goto out_unhold;
588         ip->i_qadata->qa_qd_num++;
589         qd++;
590
591         error = qdsb_get(sdp, make_kqid_gid(ip->i_inode.i_gid), qd);
592         if (error)
593                 goto out_unhold;
594         ip->i_qadata->qa_qd_num++;
595         qd++;
596
597         if (!uid_eq(uid, NO_UID_QUOTA_CHANGE) &&
598             !uid_eq(uid, ip->i_inode.i_uid)) {
599                 error = qdsb_get(sdp, make_kqid_uid(uid), qd);
600                 if (error)
601                         goto out_unhold;
602                 ip->i_qadata->qa_qd_num++;
603                 qd++;
604         }
605
606         if (!gid_eq(gid, NO_GID_QUOTA_CHANGE) &&
607             !gid_eq(gid, ip->i_inode.i_gid)) {
608                 error = qdsb_get(sdp, make_kqid_gid(gid), qd);
609                 if (error)
610                         goto out_unhold;
611                 ip->i_qadata->qa_qd_num++;
612                 qd++;
613         }
614
615 out_unhold:
616         if (error)
617                 gfs2_quota_unhold(ip);
618 out:
619         return error;
620 }
621
622 void gfs2_quota_unhold(struct gfs2_inode *ip)
623 {
624         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
625         u32 x;
626
627         if (ip->i_qadata == NULL)
628                 return;
629
630         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
631
632         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
633                 qdsb_put(ip->i_qadata->qa_qd[x]);
634                 ip->i_qadata->qa_qd[x] = NULL;
635         }
636         ip->i_qadata->qa_qd_num = 0;
637         gfs2_qa_put(ip);
638 }
639
640 static int sort_qd(const void *a, const void *b)
641 {
642         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
643         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
644
645         if (qid_lt(qd_a->qd_id, qd_b->qd_id))
646                 return -1;
647         if (qid_lt(qd_b->qd_id, qd_a->qd_id))
648                 return 1;
649         return 0;
650 }
651
652 static void do_qc(struct gfs2_quota_data *qd, s64 change)
653 {
654         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
655         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
656         struct gfs2_quota_change *qc = qd->qd_bh_qc;
657         s64 x;
658
659         mutex_lock(&sdp->sd_quota_mutex);
660         gfs2_trans_add_meta(ip->i_gl, qd->qd_bh);
661
662         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
663                 qc->qc_change = 0;
664                 qc->qc_flags = 0;
665                 if (qd->qd_id.type == USRQUOTA)
666                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
667                 qc->qc_id = cpu_to_be32(from_kqid(&init_user_ns, qd->qd_id));
668         }
669
670         x = be64_to_cpu(qc->qc_change) + change;
671         qc->qc_change = cpu_to_be64(x);
672
673         spin_lock(&qd_lock);
674         qd->qd_change = x;
675         spin_unlock(&qd_lock);
676
677         if (!x) {
678                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
679                 clear_bit(QDF_CHANGE, &qd->qd_flags);
680                 qc->qc_flags = 0;
681                 qc->qc_id = 0;
682                 slot_put(qd);
683                 qd_put(qd);
684         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
685                 qd_hold(qd);
686                 slot_hold(qd);
687         }
688
689         if (change < 0) /* Reset quiet flag if we freed some blocks */
690                 clear_bit(QDF_QMSG_QUIET, &qd->qd_flags);
691         mutex_unlock(&sdp->sd_quota_mutex);
692 }
693
694 static int gfs2_write_buf_to_page(struct gfs2_inode *ip, unsigned long index,
695                                   unsigned off, void *buf, unsigned bytes)
696 {
697         struct inode *inode = &ip->i_inode;
698         struct gfs2_sbd *sdp = GFS2_SB(inode);
699         struct address_space *mapping = inode->i_mapping;
700         struct page *page;
701         struct buffer_head *bh;
702         void *kaddr;
703         u64 blk;
704         unsigned bsize = sdp->sd_sb.sb_bsize, bnum = 0, boff = 0;
705         unsigned to_write = bytes, pg_off = off;
706         int done = 0;
707
708         blk = index << (PAGE_SHIFT - sdp->sd_sb.sb_bsize_shift);
709         boff = off % bsize;
710
711         page = find_or_create_page(mapping, index, GFP_NOFS);
712         if (!page)
713                 return -ENOMEM;
714         if (!page_has_buffers(page))
715                 create_empty_buffers(page, bsize, 0);
716
717         bh = page_buffers(page);
718         while (!done) {
719                 /* Find the beginning block within the page */
720                 if (pg_off >= ((bnum * bsize) + bsize)) {
721                         bh = bh->b_this_page;
722                         bnum++;
723                         blk++;
724                         continue;
725                 }
726                 if (!buffer_mapped(bh)) {
727                         gfs2_block_map(inode, blk, bh, 1);
728                         if (!buffer_mapped(bh))
729                                 goto unlock_out;
730                         /* If it's a newly allocated disk block, zero it */
731                         if (buffer_new(bh))
732                                 zero_user(page, bnum * bsize, bh->b_size);
733                 }
734                 if (PageUptodate(page))
735                         set_buffer_uptodate(bh);
736                 if (!buffer_uptodate(bh)) {
737                         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &bh);
738                         wait_on_buffer(bh);
739                         if (!buffer_uptodate(bh))
740                                 goto unlock_out;
741                 }
742                 if (gfs2_is_jdata(ip))
743                         gfs2_trans_add_data(ip->i_gl, bh);
744                 else
745                         gfs2_ordered_add_inode(ip);
746
747                 /* If we need to write to the next block as well */
748                 if (to_write > (bsize - boff)) {
749                         pg_off += (bsize - boff);
750                         to_write -= (bsize - boff);
751                         boff = pg_off % bsize;
752                         continue;
753                 }
754                 done = 1;
755         }
756
757         /* Write to the page, now that we have setup the buffer(s) */
758         kaddr = kmap_atomic(page);
759         memcpy(kaddr + off, buf, bytes);
760         flush_dcache_page(page);
761         kunmap_atomic(kaddr);
762         unlock_page(page);
763         put_page(page);
764
765         return 0;
766
767 unlock_out:
768         unlock_page(page);
769         put_page(page);
770         return -EIO;
771 }
772
773 static int gfs2_write_disk_quota(struct gfs2_inode *ip, struct gfs2_quota *qp,
774                                  loff_t loc)
775 {
776         unsigned long pg_beg;
777         unsigned pg_off, nbytes, overflow = 0;
778         int pg_oflow = 0, error;
779         void *ptr;
780
781         nbytes = sizeof(struct gfs2_quota);
782
783         pg_beg = loc >> PAGE_SHIFT;
784         pg_off = offset_in_page(loc);
785
786         /* If the quota straddles a page boundary, split the write in two */
787         if ((pg_off + nbytes) > PAGE_SIZE) {
788                 pg_oflow = 1;
789                 overflow = (pg_off + nbytes) - PAGE_SIZE;
790         }
791
792         ptr = qp;
793         error = gfs2_write_buf_to_page(ip, pg_beg, pg_off, ptr,
794                                        nbytes - overflow);
795         /* If there's an overflow, write the remaining bytes to the next page */
796         if (!error && pg_oflow)
797                 error = gfs2_write_buf_to_page(ip, pg_beg + 1, 0,
798                                                ptr + nbytes - overflow,
799                                                overflow);
800         return error;
801 }
802
803 /**
804  * gfs2_adjust_quota - adjust record of current block usage
805  * @ip: The quota inode
806  * @loc: Offset of the entry in the quota file
807  * @change: The amount of usage change to record
808  * @qd: The quota data
809  * @fdq: The updated limits to record
810  *
811  * This function was mostly borrowed from gfs2_block_truncate_page which was
812  * in turn mostly borrowed from ext3
813  *
814  * Returns: 0 or -ve on error
815  */
816
817 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
818                              s64 change, struct gfs2_quota_data *qd,
819                              struct qc_dqblk *fdq)
820 {
821         struct inode *inode = &ip->i_inode;
822         struct gfs2_sbd *sdp = GFS2_SB(inode);
823         struct gfs2_quota q;
824         int err;
825         u64 size;
826
827         if (gfs2_is_stuffed(ip)) {
828                 err = gfs2_unstuff_dinode(ip, NULL);
829                 if (err)
830                         return err;
831         }
832
833         memset(&q, 0, sizeof(struct gfs2_quota));
834         err = gfs2_internal_read(ip, (char *)&q, &loc, sizeof(q));
835         if (err < 0)
836                 return err;
837
838         loc -= sizeof(q); /* gfs2_internal_read would've advanced the loc ptr */
839         err = -EIO;
840         be64_add_cpu(&q.qu_value, change);
841         if (((s64)be64_to_cpu(q.qu_value)) < 0)
842                 q.qu_value = 0; /* Never go negative on quota usage */
843         qd->qd_qb.qb_value = q.qu_value;
844         if (fdq) {
845                 if (fdq->d_fieldmask & QC_SPC_SOFT) {
846                         q.qu_warn = cpu_to_be64(fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift);
847                         qd->qd_qb.qb_warn = q.qu_warn;
848                 }
849                 if (fdq->d_fieldmask & QC_SPC_HARD) {
850                         q.qu_limit = cpu_to_be64(fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift);
851                         qd->qd_qb.qb_limit = q.qu_limit;
852                 }
853                 if (fdq->d_fieldmask & QC_SPACE) {
854                         q.qu_value = cpu_to_be64(fdq->d_space >> sdp->sd_sb.sb_bsize_shift);
855                         qd->qd_qb.qb_value = q.qu_value;
856                 }
857         }
858
859         err = gfs2_write_disk_quota(ip, &q, loc);
860         if (!err) {
861                 size = loc + sizeof(struct gfs2_quota);
862                 if (size > inode->i_size)
863                         i_size_write(inode, size);
864                 inode->i_mtime = inode->i_atime = current_time(inode);
865                 mark_inode_dirty(inode);
866                 set_bit(QDF_REFRESH, &qd->qd_flags);
867         }
868
869         return err;
870 }
871
872 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
873 {
874         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_name.ln_sbd;
875         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
876         struct gfs2_alloc_parms ap = { .aflags = 0, };
877         unsigned int data_blocks, ind_blocks;
878         struct gfs2_holder *ghs, i_gh;
879         unsigned int qx, x;
880         struct gfs2_quota_data *qd;
881         unsigned reserved;
882         loff_t offset;
883         unsigned int nalloc = 0, blocks;
884         int error;
885
886         error = gfs2_qa_get(ip);
887         if (error)
888                 return error;
889
890         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
891                               &data_blocks, &ind_blocks);
892
893         ghs = kmalloc_array(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
894         if (!ghs) {
895                 error = -ENOMEM;
896                 goto out;
897         }
898
899         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
900         inode_lock(&ip->i_inode);
901         for (qx = 0; qx < num_qd; qx++) {
902                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
903                                            GL_NOCACHE, &ghs[qx]);
904                 if (error)
905                         goto out_dq;
906         }
907
908         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
909         if (error)
910                 goto out_dq;
911
912         for (x = 0; x < num_qd; x++) {
913                 offset = qd2offset(qda[x]);
914                 if (gfs2_write_alloc_required(ip, offset,
915                                               sizeof(struct gfs2_quota)))
916                         nalloc++;
917         }
918
919         /* 
920          * 1 blk for unstuffing inode if stuffed. We add this extra
921          * block to the reservation unconditionally. If the inode
922          * doesn't need unstuffing, the block will be released to the 
923          * rgrp since it won't be allocated during the transaction
924          */
925         /* +3 in the end for unstuffing block, inode size update block
926          * and another block in case quota straddles page boundary and 
927          * two blocks need to be updated instead of 1 */
928         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
929
930         reserved = 1 + (nalloc * (data_blocks + ind_blocks));
931         ap.target = reserved;
932         error = gfs2_inplace_reserve(ip, &ap);
933         if (error)
934                 goto out_alloc;
935
936         if (nalloc)
937                 blocks += gfs2_rg_blocks(ip, reserved) + nalloc * ind_blocks + RES_STATFS;
938
939         error = gfs2_trans_begin(sdp, blocks, 0);
940         if (error)
941                 goto out_ipres;
942
943         for (x = 0; x < num_qd; x++) {
944                 qd = qda[x];
945                 offset = qd2offset(qd);
946                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
947                 if (error)
948                         goto out_end_trans;
949
950                 do_qc(qd, -qd->qd_change_sync);
951                 set_bit(QDF_REFRESH, &qd->qd_flags);
952         }
953
954         error = 0;
955
956 out_end_trans:
957         gfs2_trans_end(sdp);
958 out_ipres:
959         gfs2_inplace_release(ip);
960 out_alloc:
961         gfs2_glock_dq_uninit(&i_gh);
962 out_dq:
963         while (qx--)
964                 gfs2_glock_dq_uninit(&ghs[qx]);
965         inode_unlock(&ip->i_inode);
966         kfree(ghs);
967         gfs2_log_flush(ip->i_gl->gl_name.ln_sbd, ip->i_gl,
968                        GFS2_LOG_HEAD_FLUSH_NORMAL | GFS2_LFC_DO_SYNC);
969 out:
970         gfs2_qa_put(ip);
971         return error;
972 }
973
974 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
975 {
976         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
977         struct gfs2_quota q;
978         struct gfs2_quota_lvb *qlvb;
979         loff_t pos;
980         int error;
981
982         memset(&q, 0, sizeof(struct gfs2_quota));
983         pos = qd2offset(qd);
984         error = gfs2_internal_read(ip, (char *)&q, &pos, sizeof(q));
985         if (error < 0)
986                 return error;
987
988         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
989         qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
990         qlvb->__pad = 0;
991         qlvb->qb_limit = q.qu_limit;
992         qlvb->qb_warn = q.qu_warn;
993         qlvb->qb_value = q.qu_value;
994         qd->qd_qb = *qlvb;
995
996         return 0;
997 }
998
999 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
1000                     struct gfs2_holder *q_gh)
1001 {
1002         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1003         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1004         struct gfs2_holder i_gh;
1005         int error;
1006
1007 restart:
1008         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
1009         if (error)
1010                 return error;
1011
1012         if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
1013                 force_refresh = FORCE;
1014
1015         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1016
1017         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
1018                 gfs2_glock_dq_uninit(q_gh);
1019                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
1020                                            GL_NOCACHE, q_gh);
1021                 if (error)
1022                         return error;
1023
1024                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
1025                 if (error)
1026                         goto fail;
1027
1028                 error = update_qd(sdp, qd);
1029                 if (error)
1030                         goto fail_gunlock;
1031
1032                 gfs2_glock_dq_uninit(&i_gh);
1033                 gfs2_glock_dq_uninit(q_gh);
1034                 force_refresh = 0;
1035                 goto restart;
1036         }
1037
1038         return 0;
1039
1040 fail_gunlock:
1041         gfs2_glock_dq_uninit(&i_gh);
1042 fail:
1043         gfs2_glock_dq_uninit(q_gh);
1044         return error;
1045 }
1046
1047 int gfs2_quota_lock(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
1048 {
1049         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1050         struct gfs2_quota_data *qd;
1051         u32 x;
1052         int error = 0;
1053
1054         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1055                 return 0;
1056
1057         error = gfs2_quota_hold(ip, uid, gid);
1058         if (error)
1059                 return error;
1060
1061         sort(ip->i_qadata->qa_qd, ip->i_qadata->qa_qd_num,
1062              sizeof(struct gfs2_quota_data *), sort_qd, NULL);
1063
1064         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1065                 qd = ip->i_qadata->qa_qd[x];
1066                 error = do_glock(qd, NO_FORCE, &ip->i_qadata->qa_qd_ghs[x]);
1067                 if (error)
1068                         break;
1069         }
1070
1071         if (!error)
1072                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
1073         else {
1074                 while (x--)
1075                         gfs2_glock_dq_uninit(&ip->i_qadata->qa_qd_ghs[x]);
1076                 gfs2_quota_unhold(ip);
1077         }
1078
1079         return error;
1080 }
1081
1082 static int need_sync(struct gfs2_quota_data *qd)
1083 {
1084         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1085         struct gfs2_tune *gt = &sdp->sd_tune;
1086         s64 value;
1087         unsigned int num, den;
1088         int do_sync = 1;
1089
1090         if (!qd->qd_qb.qb_limit)
1091                 return 0;
1092
1093         spin_lock(&qd_lock);
1094         value = qd->qd_change;
1095         spin_unlock(&qd_lock);
1096
1097         spin_lock(&gt->gt_spin);
1098         num = gt->gt_quota_scale_num;
1099         den = gt->gt_quota_scale_den;
1100         spin_unlock(&gt->gt_spin);
1101
1102         if (value < 0)
1103                 do_sync = 0;
1104         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
1105                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1106                 do_sync = 0;
1107         else {
1108                 value *= gfs2_jindex_size(sdp) * num;
1109                 value = div_s64(value, den);
1110                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
1111                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1112                         do_sync = 0;
1113         }
1114
1115         return do_sync;
1116 }
1117
1118 void gfs2_quota_unlock(struct gfs2_inode *ip)
1119 {
1120         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1121         struct gfs2_quota_data *qda[4];
1122         unsigned int count = 0;
1123         u32 x;
1124         int found;
1125
1126         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1127                 goto out;
1128
1129         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1130                 struct gfs2_quota_data *qd;
1131                 int sync;
1132
1133                 qd = ip->i_qadata->qa_qd[x];
1134                 sync = need_sync(qd);
1135
1136                 gfs2_glock_dq_uninit(&ip->i_qadata->qa_qd_ghs[x]);
1137                 if (!sync)
1138                         continue;
1139
1140                 spin_lock(&qd_lock);
1141                 found = qd_check_sync(sdp, qd, NULL);
1142                 spin_unlock(&qd_lock);
1143
1144                 if (!found)
1145                         continue;
1146
1147                 gfs2_assert_warn(sdp, qd->qd_change_sync);
1148                 if (bh_get(qd)) {
1149                         clear_bit(QDF_LOCKED, &qd->qd_flags);
1150                         slot_put(qd);
1151                         qd_put(qd);
1152                         continue;
1153                 }
1154
1155                 qda[count++] = qd;
1156         }
1157
1158         if (count) {
1159                 do_sync(count, qda);
1160                 for (x = 0; x < count; x++)
1161                         qd_unlock(qda[x]);
1162         }
1163
1164 out:
1165         gfs2_quota_unhold(ip);
1166 }
1167
1168 #define MAX_LINE 256
1169
1170 static int print_message(struct gfs2_quota_data *qd, char *type)
1171 {
1172         struct gfs2_sbd *sdp = qd->qd_gl->gl_name.ln_sbd;
1173
1174         fs_info(sdp, "quota %s for %s %u\n",
1175                 type,
1176                 (qd->qd_id.type == USRQUOTA) ? "user" : "group",
1177                 from_kqid(&init_user_ns, qd->qd_id));
1178
1179         return 0;
1180 }
1181
1182 /**
1183  * gfs2_quota_check - check if allocating new blocks will exceed quota
1184  * @ip:  The inode for which this check is being performed
1185  * @uid: The uid to check against
1186  * @gid: The gid to check against
1187  * @ap:  The allocation parameters. ap->target contains the requested
1188  *       blocks. ap->min_target, if set, contains the minimum blks
1189  *       requested.
1190  *
1191  * Returns: 0 on success.
1192  *                  min_req = ap->min_target ? ap->min_target : ap->target;
1193  *                  quota must allow at least min_req blks for success and
1194  *                  ap->allowed is set to the number of blocks allowed
1195  *
1196  *          -EDQUOT otherwise, quota violation. ap->allowed is set to number
1197  *                  of blocks available.
1198  */
1199 int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid,
1200                      struct gfs2_alloc_parms *ap)
1201 {
1202         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1203         struct gfs2_quota_data *qd;
1204         s64 value, warn, limit;
1205         u32 x;
1206         int error = 0;
1207
1208         ap->allowed = UINT_MAX; /* Assume we are permitted a whole lot */
1209         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1210                 return 0;
1211
1212         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1213                 qd = ip->i_qadata->qa_qd[x];
1214
1215                 if (!(qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1216                       qid_eq(qd->qd_id, make_kqid_gid(gid))))
1217                         continue;
1218
1219                 warn = (s64)be64_to_cpu(qd->qd_qb.qb_warn);
1220                 limit = (s64)be64_to_cpu(qd->qd_qb.qb_limit);
1221                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1222                 spin_lock(&qd_lock);
1223                 value += qd->qd_change;
1224                 spin_unlock(&qd_lock);
1225
1226                 if (limit > 0 && (limit - value) < ap->allowed)
1227                         ap->allowed = limit - value;
1228                 /* If we can't meet the target */
1229                 if (limit && limit < (value + (s64)ap->target)) {
1230                         /* If no min_target specified or we don't meet
1231                          * min_target, return -EDQUOT */
1232                         if (!ap->min_target || ap->min_target > ap->allowed) {
1233                                 if (!test_and_set_bit(QDF_QMSG_QUIET,
1234                                                       &qd->qd_flags)) {
1235                                         print_message(qd, "exceeded");
1236                                         quota_send_warning(qd->qd_id,
1237                                                            sdp->sd_vfs->s_dev,
1238                                                            QUOTA_NL_BHARDWARN);
1239                                 }
1240                                 error = -EDQUOT;
1241                                 break;
1242                         }
1243                 } else if (warn && warn < value &&
1244                            time_after_eq(jiffies, qd->qd_last_warn +
1245                                          gfs2_tune_get(sdp, gt_quota_warn_period)
1246                                          * HZ)) {
1247                         quota_send_warning(qd->qd_id,
1248                                            sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1249                         error = print_message(qd, "warning");
1250                         qd->qd_last_warn = jiffies;
1251                 }
1252         }
1253         return error;
1254 }
1255
1256 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1257                        kuid_t uid, kgid_t gid)
1258 {
1259         struct gfs2_quota_data *qd;
1260         u32 x;
1261         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1262
1263         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON ||
1264             gfs2_assert_warn(sdp, change))
1265                 return;
1266         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1267                 return;
1268
1269         if (gfs2_assert_withdraw(sdp, ip->i_qadata &&
1270                                  ip->i_qadata->qa_ref > 0))
1271                 return;
1272         for (x = 0; x < ip->i_qadata->qa_qd_num; x++) {
1273                 qd = ip->i_qadata->qa_qd[x];
1274
1275                 if (qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1276                     qid_eq(qd->qd_id, make_kqid_gid(gid))) {
1277                         do_qc(qd, change);
1278                 }
1279         }
1280 }
1281
1282 int gfs2_quota_sync(struct super_block *sb, int type)
1283 {
1284         struct gfs2_sbd *sdp = sb->s_fs_info;
1285         struct gfs2_quota_data **qda;
1286         unsigned int max_qd = PAGE_SIZE / sizeof(struct gfs2_holder);
1287         unsigned int num_qd;
1288         unsigned int x;
1289         int error = 0;
1290
1291         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1292         if (!qda)
1293                 return -ENOMEM;
1294
1295         mutex_lock(&sdp->sd_quota_sync_mutex);
1296         sdp->sd_quota_sync_gen++;
1297
1298         do {
1299                 num_qd = 0;
1300
1301                 for (;;) {
1302                         error = qd_fish(sdp, qda + num_qd);
1303                         if (error || !qda[num_qd])
1304                                 break;
1305                         if (++num_qd == max_qd)
1306                                 break;
1307                 }
1308
1309                 if (num_qd) {
1310                         if (!error)
1311                                 error = do_sync(num_qd, qda);
1312                         if (!error)
1313                                 for (x = 0; x < num_qd; x++)
1314                                         qda[x]->qd_sync_gen =
1315                                                 sdp->sd_quota_sync_gen;
1316
1317                         for (x = 0; x < num_qd; x++)
1318                                 qd_unlock(qda[x]);
1319                 }
1320         } while (!error && num_qd == max_qd);
1321
1322         mutex_unlock(&sdp->sd_quota_sync_mutex);
1323         kfree(qda);
1324
1325         return error;
1326 }
1327
1328 int gfs2_quota_refresh(struct gfs2_sbd *sdp, struct kqid qid)
1329 {
1330         struct gfs2_quota_data *qd;
1331         struct gfs2_holder q_gh;
1332         int error;
1333
1334         error = qd_get(sdp, qid, &qd);
1335         if (error)
1336                 return error;
1337
1338         error = do_glock(qd, FORCE, &q_gh);
1339         if (!error)
1340                 gfs2_glock_dq_uninit(&q_gh);
1341
1342         qd_put(qd);
1343         return error;
1344 }
1345
1346 int gfs2_quota_init(struct gfs2_sbd *sdp)
1347 {
1348         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1349         u64 size = i_size_read(sdp->sd_qc_inode);
1350         unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1351         unsigned int x, slot = 0;
1352         unsigned int found = 0;
1353         unsigned int hash;
1354         unsigned int bm_size;
1355         u64 dblock;
1356         u32 extlen = 0;
1357         int error;
1358
1359         if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1360                 return -EIO;
1361
1362         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1363         bm_size = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * sizeof(unsigned long));
1364         bm_size *= sizeof(unsigned long);
1365         error = -ENOMEM;
1366         sdp->sd_quota_bitmap = kzalloc(bm_size, GFP_NOFS | __GFP_NOWARN);
1367         if (sdp->sd_quota_bitmap == NULL)
1368                 sdp->sd_quota_bitmap = __vmalloc(bm_size, GFP_NOFS |
1369                                                  __GFP_ZERO, PAGE_KERNEL);
1370         if (!sdp->sd_quota_bitmap)
1371                 return error;
1372
1373         for (x = 0; x < blocks; x++) {
1374                 struct buffer_head *bh;
1375                 const struct gfs2_quota_change *qc;
1376                 unsigned int y;
1377
1378                 if (!extlen) {
1379                         int new = 0;
1380                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1381                         if (error)
1382                                 goto fail;
1383                 }
1384                 error = -EIO;
1385                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1386                 if (!bh)
1387                         goto fail;
1388                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1389                         brelse(bh);
1390                         goto fail;
1391                 }
1392
1393                 qc = (const struct gfs2_quota_change *)(bh->b_data + sizeof(struct gfs2_meta_header));
1394                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1395                      y++, slot++) {
1396                         struct gfs2_quota_data *qd;
1397                         s64 qc_change = be64_to_cpu(qc->qc_change);
1398                         u32 qc_flags = be32_to_cpu(qc->qc_flags);
1399                         enum quota_type qtype = (qc_flags & GFS2_QCF_USER) ?
1400                                                 USRQUOTA : GRPQUOTA;
1401                         struct kqid qc_id = make_kqid(&init_user_ns, qtype,
1402                                                       be32_to_cpu(qc->qc_id));
1403                         qc++;
1404                         if (!qc_change)
1405                                 continue;
1406
1407                         hash = gfs2_qd_hash(sdp, qc_id);
1408                         qd = qd_alloc(hash, sdp, qc_id);
1409                         if (qd == NULL) {
1410                                 brelse(bh);
1411                                 goto fail;
1412                         }
1413
1414                         set_bit(QDF_CHANGE, &qd->qd_flags);
1415                         qd->qd_change = qc_change;
1416                         qd->qd_slot = slot;
1417                         qd->qd_slot_count = 1;
1418
1419                         spin_lock(&qd_lock);
1420                         BUG_ON(test_and_set_bit(slot, sdp->sd_quota_bitmap));
1421                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1422                         atomic_inc(&sdp->sd_quota_count);
1423                         spin_unlock(&qd_lock);
1424
1425                         spin_lock_bucket(hash);
1426                         hlist_bl_add_head_rcu(&qd->qd_hlist, &qd_hash_table[hash]);
1427                         spin_unlock_bucket(hash);
1428
1429                         found++;
1430                 }
1431
1432                 brelse(bh);
1433                 dblock++;
1434                 extlen--;
1435         }
1436
1437         if (found)
1438                 fs_info(sdp, "found %u quota changes\n", found);
1439
1440         return 0;
1441
1442 fail:
1443         gfs2_quota_cleanup(sdp);
1444         return error;
1445 }
1446
1447 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1448 {
1449         struct list_head *head = &sdp->sd_quota_list;
1450         struct gfs2_quota_data *qd;
1451
1452         spin_lock(&qd_lock);
1453         while (!list_empty(head)) {
1454                 qd = list_last_entry(head, struct gfs2_quota_data, qd_list);
1455
1456                 list_del(&qd->qd_list);
1457
1458                 /* Also remove if this qd exists in the reclaim list */
1459                 list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
1460                 atomic_dec(&sdp->sd_quota_count);
1461                 spin_unlock(&qd_lock);
1462
1463                 spin_lock_bucket(qd->qd_hash);
1464                 hlist_bl_del_rcu(&qd->qd_hlist);
1465                 spin_unlock_bucket(qd->qd_hash);
1466
1467                 gfs2_assert_warn(sdp, !qd->qd_change);
1468                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1469                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1470
1471                 gfs2_glock_put(qd->qd_gl);
1472                 call_rcu(&qd->qd_rcu, gfs2_qd_dealloc);
1473
1474                 spin_lock(&qd_lock);
1475         }
1476         spin_unlock(&qd_lock);
1477
1478         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1479
1480         kvfree(sdp->sd_quota_bitmap);
1481         sdp->sd_quota_bitmap = NULL;
1482 }
1483
1484 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1485 {
1486         if (error == 0 || error == -EROFS)
1487                 return;
1488         if (!gfs2_withdrawn(sdp)) {
1489                 if (!cmpxchg(&sdp->sd_log_error, 0, error))
1490                         fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1491                 wake_up(&sdp->sd_logd_waitq);
1492         }
1493 }
1494
1495 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1496                                int (*fxn)(struct super_block *sb, int type),
1497                                unsigned long t, unsigned long *timeo,
1498                                unsigned int *new_timeo)
1499 {
1500         if (t >= *timeo) {
1501                 int error = fxn(sdp->sd_vfs, 0);
1502                 quotad_error(sdp, msg, error);
1503                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1504         } else {
1505                 *timeo -= t;
1506         }
1507 }
1508
1509 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1510 {
1511         struct gfs2_inode *ip;
1512
1513         while(1) {
1514                 ip = NULL;
1515                 spin_lock(&sdp->sd_trunc_lock);
1516                 if (!list_empty(&sdp->sd_trunc_list)) {
1517                         ip = list_first_entry(&sdp->sd_trunc_list,
1518                                         struct gfs2_inode, i_trunc_list);
1519                         list_del_init(&ip->i_trunc_list);
1520                 }
1521                 spin_unlock(&sdp->sd_trunc_lock);
1522                 if (ip == NULL)
1523                         return;
1524                 gfs2_glock_finish_truncate(ip);
1525         }
1526 }
1527
1528 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1529         if (!sdp->sd_statfs_force_sync) {
1530                 sdp->sd_statfs_force_sync = 1;
1531                 wake_up(&sdp->sd_quota_wait);
1532         }
1533 }
1534
1535
1536 /**
1537  * gfs2_quotad - Write cached quota changes into the quota file
1538  * @sdp: Pointer to GFS2 superblock
1539  *
1540  */
1541
1542 int gfs2_quotad(void *data)
1543 {
1544         struct gfs2_sbd *sdp = data;
1545         struct gfs2_tune *tune = &sdp->sd_tune;
1546         unsigned long statfs_timeo = 0;
1547         unsigned long quotad_timeo = 0;
1548         unsigned long t = 0;
1549         DEFINE_WAIT(wait);
1550         int empty;
1551
1552         while (!kthread_should_stop()) {
1553
1554                 if (gfs2_withdrawn(sdp))
1555                         goto bypass;
1556                 /* Update the master statfs file */
1557                 if (sdp->sd_statfs_force_sync) {
1558                         int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1559                         quotad_error(sdp, "statfs", error);
1560                         statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1561                 }
1562                 else
1563                         quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1564                                            &statfs_timeo,
1565                                            &tune->gt_statfs_quantum);
1566
1567                 /* Update quota file */
1568                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
1569                                    &quotad_timeo, &tune->gt_quota_quantum);
1570
1571                 /* Check for & recover partially truncated inodes */
1572                 quotad_check_trunc_list(sdp);
1573
1574                 try_to_freeze();
1575
1576 bypass:
1577                 t = min(quotad_timeo, statfs_timeo);
1578
1579                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1580                 spin_lock(&sdp->sd_trunc_lock);
1581                 empty = list_empty(&sdp->sd_trunc_list);
1582                 spin_unlock(&sdp->sd_trunc_lock);
1583                 if (empty && !sdp->sd_statfs_force_sync)
1584                         t -= schedule_timeout(t);
1585                 else
1586                         t = 0;
1587                 finish_wait(&sdp->sd_quota_wait, &wait);
1588         }
1589
1590         return 0;
1591 }
1592
1593 static int gfs2_quota_get_state(struct super_block *sb, struct qc_state *state)
1594 {
1595         struct gfs2_sbd *sdp = sb->s_fs_info;
1596
1597         memset(state, 0, sizeof(*state));
1598
1599         switch (sdp->sd_args.ar_quota) {
1600         case GFS2_QUOTA_ON:
1601                 state->s_state[USRQUOTA].flags |= QCI_LIMITS_ENFORCED;
1602                 state->s_state[GRPQUOTA].flags |= QCI_LIMITS_ENFORCED;
1603                 /*FALLTHRU*/
1604         case GFS2_QUOTA_ACCOUNT:
1605                 state->s_state[USRQUOTA].flags |= QCI_ACCT_ENABLED |
1606                                                   QCI_SYSFILE;
1607                 state->s_state[GRPQUOTA].flags |= QCI_ACCT_ENABLED |
1608                                                   QCI_SYSFILE;
1609                 break;
1610         case GFS2_QUOTA_OFF:
1611                 break;
1612         }
1613         if (sdp->sd_quota_inode) {
1614                 state->s_state[USRQUOTA].ino =
1615                                         GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1616                 state->s_state[USRQUOTA].blocks = sdp->sd_quota_inode->i_blocks;
1617         }
1618         state->s_state[USRQUOTA].nextents = 1;  /* unsupported */
1619         state->s_state[GRPQUOTA] = state->s_state[USRQUOTA];
1620         state->s_incoredqs = list_lru_count(&gfs2_qd_lru);
1621         return 0;
1622 }
1623
1624 static int gfs2_get_dqblk(struct super_block *sb, struct kqid qid,
1625                           struct qc_dqblk *fdq)
1626 {
1627         struct gfs2_sbd *sdp = sb->s_fs_info;
1628         struct gfs2_quota_lvb *qlvb;
1629         struct gfs2_quota_data *qd;
1630         struct gfs2_holder q_gh;
1631         int error;
1632
1633         memset(fdq, 0, sizeof(*fdq));
1634
1635         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1636                 return -ESRCH; /* Crazy XFS error code */
1637
1638         if ((qid.type != USRQUOTA) &&
1639             (qid.type != GRPQUOTA))
1640                 return -EINVAL;
1641
1642         error = qd_get(sdp, qid, &qd);
1643         if (error)
1644                 return error;
1645         error = do_glock(qd, FORCE, &q_gh);
1646         if (error)
1647                 goto out;
1648
1649         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1650         fdq->d_spc_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_sb.sb_bsize_shift;
1651         fdq->d_spc_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_sb.sb_bsize_shift;
1652         fdq->d_space = be64_to_cpu(qlvb->qb_value) << sdp->sd_sb.sb_bsize_shift;
1653
1654         gfs2_glock_dq_uninit(&q_gh);
1655 out:
1656         qd_put(qd);
1657         return error;
1658 }
1659
1660 /* GFS2 only supports a subset of the XFS fields */
1661 #define GFS2_FIELDMASK (QC_SPC_SOFT|QC_SPC_HARD|QC_SPACE)
1662
1663 static int gfs2_set_dqblk(struct super_block *sb, struct kqid qid,
1664                           struct qc_dqblk *fdq)
1665 {
1666         struct gfs2_sbd *sdp = sb->s_fs_info;
1667         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1668         struct gfs2_quota_data *qd;
1669         struct gfs2_holder q_gh, i_gh;
1670         unsigned int data_blocks, ind_blocks;
1671         unsigned int blocks = 0;
1672         int alloc_required;
1673         loff_t offset;
1674         int error;
1675
1676         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1677                 return -ESRCH; /* Crazy XFS error code */
1678
1679         if ((qid.type != USRQUOTA) &&
1680             (qid.type != GRPQUOTA))
1681                 return -EINVAL;
1682
1683         if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1684                 return -EINVAL;
1685
1686         error = qd_get(sdp, qid, &qd);
1687         if (error)
1688                 return error;
1689
1690         error = gfs2_qa_get(ip);
1691         if (error)
1692                 goto out_put;
1693
1694         inode_lock(&ip->i_inode);
1695         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1696         if (error)
1697                 goto out_unlockput;
1698         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1699         if (error)
1700                 goto out_q;
1701
1702         /* Check for existing entry, if none then alloc new blocks */
1703         error = update_qd(sdp, qd);
1704         if (error)
1705                 goto out_i;
1706
1707         /* If nothing has changed, this is a no-op */
1708         if ((fdq->d_fieldmask & QC_SPC_SOFT) &&
1709             ((fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1710                 fdq->d_fieldmask ^= QC_SPC_SOFT;
1711
1712         if ((fdq->d_fieldmask & QC_SPC_HARD) &&
1713             ((fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1714                 fdq->d_fieldmask ^= QC_SPC_HARD;
1715
1716         if ((fdq->d_fieldmask & QC_SPACE) &&
1717             ((fdq->d_space >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1718                 fdq->d_fieldmask ^= QC_SPACE;
1719
1720         if (fdq->d_fieldmask == 0)
1721                 goto out_i;
1722
1723         offset = qd2offset(qd);
1724         alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1725         if (gfs2_is_stuffed(ip))
1726                 alloc_required = 1;
1727         if (alloc_required) {
1728                 struct gfs2_alloc_parms ap = { .aflags = 0, };
1729                 gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1730                                        &data_blocks, &ind_blocks);
1731                 blocks = 1 + data_blocks + ind_blocks;
1732                 ap.target = blocks;
1733                 error = gfs2_inplace_reserve(ip, &ap);
1734                 if (error)
1735                         goto out_i;
1736                 blocks += gfs2_rg_blocks(ip, blocks);
1737         }
1738
1739         /* Some quotas span block boundaries and can update two blocks,
1740            adding an extra block to the transaction to handle such quotas */
1741         error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1742         if (error)
1743                 goto out_release;
1744
1745         /* Apply changes */
1746         error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1747         if (!error)
1748                 clear_bit(QDF_QMSG_QUIET, &qd->qd_flags);
1749
1750         gfs2_trans_end(sdp);
1751 out_release:
1752         if (alloc_required)
1753                 gfs2_inplace_release(ip);
1754 out_i:
1755         gfs2_glock_dq_uninit(&i_gh);
1756 out_q:
1757         gfs2_glock_dq_uninit(&q_gh);
1758 out_unlockput:
1759         gfs2_qa_put(ip);
1760         inode_unlock(&ip->i_inode);
1761 out_put:
1762         qd_put(qd);
1763         return error;
1764 }
1765
1766 const struct quotactl_ops gfs2_quotactl_ops = {
1767         .quota_sync     = gfs2_quota_sync,
1768         .get_state      = gfs2_quota_get_state,
1769         .get_dqblk      = gfs2_get_dqblk,
1770         .set_dqblk      = gfs2_set_dqblk,
1771 };
1772
1773 void __init gfs2_quota_hash_init(void)
1774 {
1775         unsigned i;
1776
1777         for(i = 0; i < GFS2_QD_HASH_SIZE; i++)
1778                 INIT_HLIST_BL_HEAD(&qd_hash_table[i]);
1779 }