Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph...
[pandora-kernel.git] / fs / gfs2 / quota.c
1 /*
2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3  * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
4  *
5  * This copyrighted material is made available to anyone wishing to use,
6  * modify, copy, or redistribute it subject to the terms and conditions
7  * of the GNU General Public License version 2.
8  */
9
10 /*
11  * Quota change tags are associated with each transaction that allocates or
12  * deallocates space.  Those changes are accumulated locally to each node (in a
13  * per-node file) and then are periodically synced to the quota file.  This
14  * avoids the bottleneck of constantly touching the quota file, but introduces
15  * fuzziness in the current usage value of IDs that are being used on different
16  * nodes in the cluster simultaneously.  So, it is possible for a user on
17  * multiple nodes to overrun their quota, but that overrun is controlable.
18  * Since quota tags are part of transactions, there is no need for a quota check
19  * program to be run on node crashes or anything like that.
20  *
21  * There are couple of knobs that let the administrator manage the quota
22  * fuzziness.  "quota_quantum" sets the maximum time a quota change can be
23  * sitting on one node before being synced to the quota file.  (The default is
24  * 60 seconds.)  Another knob, "quota_scale" controls how quickly the frequency
25  * of quota file syncs increases as the user moves closer to their limit.  The
26  * more frequent the syncs, the more accurate the quota enforcement, but that
27  * means that there is more contention between the nodes for the quota file.
28  * The default value is one.  This sets the maximum theoretical quota overrun
29  * (with infinite node with infinite bandwidth) to twice the user's limit.  (In
30  * practice, the maximum overrun you see should be much less.)  A "quota_scale"
31  * number greater than one makes quota syncs more frequent and reduces the
32  * maximum overrun.  Numbers less than one (but greater than zero) make quota
33  * syncs less frequent.
34  *
35  * GFS quotas also use per-ID Lock Value Blocks (LVBs) to cache the contents of
36  * the quota file, so it is not being constantly read.
37  */
38
39 #include <linux/sched.h>
40 #include <linux/slab.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
53 #include "gfs2.h"
54 #include "incore.h"
55 #include "bmap.h"
56 #include "glock.h"
57 #include "glops.h"
58 #include "log.h"
59 #include "meta_io.h"
60 #include "quota.h"
61 #include "rgrp.h"
62 #include "super.h"
63 #include "trans.h"
64 #include "inode.h"
65 #include "util.h"
66
67 #define QUOTA_USER 1
68 #define QUOTA_GROUP 0
69
70 struct gfs2_quota_change_host {
71         u64 qc_change;
72         u32 qc_flags; /* GFS2_QCF_... */
73         u32 qc_id;
74 };
75
76 static LIST_HEAD(qd_lru_list);
77 static atomic_t qd_lru_count = ATOMIC_INIT(0);
78 static DEFINE_SPINLOCK(qd_lru_lock);
79
80 int gfs2_shrink_qd_memory(struct shrinker *shrink, int nr, gfp_t gfp_mask)
81 {
82         struct gfs2_quota_data *qd;
83         struct gfs2_sbd *sdp;
84
85         if (nr == 0)
86                 goto out;
87
88         if (!(gfp_mask & __GFP_FS))
89                 return -1;
90
91         spin_lock(&qd_lru_lock);
92         while (nr && !list_empty(&qd_lru_list)) {
93                 qd = list_entry(qd_lru_list.next,
94                                 struct gfs2_quota_data, qd_reclaim);
95                 sdp = qd->qd_gl->gl_sbd;
96
97                 /* Free from the filesystem-specific list */
98                 list_del(&qd->qd_list);
99
100                 gfs2_assert_warn(sdp, !qd->qd_change);
101                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
102                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
103
104                 gfs2_glock_put(qd->qd_gl);
105                 atomic_dec(&sdp->sd_quota_count);
106
107                 /* Delete it from the common reclaim list */
108                 list_del_init(&qd->qd_reclaim);
109                 atomic_dec(&qd_lru_count);
110                 spin_unlock(&qd_lru_lock);
111                 kmem_cache_free(gfs2_quotad_cachep, qd);
112                 spin_lock(&qd_lru_lock);
113                 nr--;
114         }
115         spin_unlock(&qd_lru_lock);
116
117 out:
118         return (atomic_read(&qd_lru_count) * sysctl_vfs_cache_pressure) / 100;
119 }
120
121 static u64 qd2offset(struct gfs2_quota_data *qd)
122 {
123         u64 offset;
124
125         offset = 2 * (u64)qd->qd_id + !test_bit(QDF_USER, &qd->qd_flags);
126         offset *= sizeof(struct gfs2_quota);
127
128         return offset;
129 }
130
131 static int qd_alloc(struct gfs2_sbd *sdp, int user, u32 id,
132                     struct gfs2_quota_data **qdp)
133 {
134         struct gfs2_quota_data *qd;
135         int error;
136
137         qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
138         if (!qd)
139                 return -ENOMEM;
140
141         atomic_set(&qd->qd_count, 1);
142         qd->qd_id = id;
143         if (user)
144                 set_bit(QDF_USER, &qd->qd_flags);
145         qd->qd_slot = -1;
146         INIT_LIST_HEAD(&qd->qd_reclaim);
147
148         error = gfs2_glock_get(sdp, 2 * (u64)id + !user,
149                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
150         if (error)
151                 goto fail;
152
153         *qdp = qd;
154
155         return 0;
156
157 fail:
158         kmem_cache_free(gfs2_quotad_cachep, qd);
159         return error;
160 }
161
162 static int qd_get(struct gfs2_sbd *sdp, int user, u32 id,
163                   struct gfs2_quota_data **qdp)
164 {
165         struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
166         int error, found;
167
168         *qdp = NULL;
169
170         for (;;) {
171                 found = 0;
172                 spin_lock(&qd_lru_lock);
173                 list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
174                         if (qd->qd_id == id &&
175                             !test_bit(QDF_USER, &qd->qd_flags) == !user) {
176                                 if (!atomic_read(&qd->qd_count) &&
177                                     !list_empty(&qd->qd_reclaim)) {
178                                         /* Remove it from reclaim list */
179                                         list_del_init(&qd->qd_reclaim);
180                                         atomic_dec(&qd_lru_count);
181                                 }
182                                 atomic_inc(&qd->qd_count);
183                                 found = 1;
184                                 break;
185                         }
186                 }
187
188                 if (!found)
189                         qd = NULL;
190
191                 if (!qd && new_qd) {
192                         qd = new_qd;
193                         list_add(&qd->qd_list, &sdp->sd_quota_list);
194                         atomic_inc(&sdp->sd_quota_count);
195                         new_qd = NULL;
196                 }
197
198                 spin_unlock(&qd_lru_lock);
199
200                 if (qd) {
201                         if (new_qd) {
202                                 gfs2_glock_put(new_qd->qd_gl);
203                                 kmem_cache_free(gfs2_quotad_cachep, new_qd);
204                         }
205                         *qdp = qd;
206                         return 0;
207                 }
208
209                 error = qd_alloc(sdp, user, id, &new_qd);
210                 if (error)
211                         return error;
212         }
213 }
214
215 static void qd_hold(struct gfs2_quota_data *qd)
216 {
217         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
218         gfs2_assert(sdp, atomic_read(&qd->qd_count));
219         atomic_inc(&qd->qd_count);
220 }
221
222 static void qd_put(struct gfs2_quota_data *qd)
223 {
224         if (atomic_dec_and_lock(&qd->qd_count, &qd_lru_lock)) {
225                 /* Add to the reclaim list */
226                 list_add_tail(&qd->qd_reclaim, &qd_lru_list);
227                 atomic_inc(&qd_lru_count);
228                 spin_unlock(&qd_lru_lock);
229         }
230 }
231
232 static int slot_get(struct gfs2_quota_data *qd)
233 {
234         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
235         unsigned int c, o = 0, b;
236         unsigned char byte = 0;
237
238         spin_lock(&qd_lru_lock);
239
240         if (qd->qd_slot_count++) {
241                 spin_unlock(&qd_lru_lock);
242                 return 0;
243         }
244
245         for (c = 0; c < sdp->sd_quota_chunks; c++)
246                 for (o = 0; o < PAGE_SIZE; o++) {
247                         byte = sdp->sd_quota_bitmap[c][o];
248                         if (byte != 0xFF)
249                                 goto found;
250                 }
251
252         goto fail;
253
254 found:
255         for (b = 0; b < 8; b++)
256                 if (!(byte & (1 << b)))
257                         break;
258         qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
259
260         if (qd->qd_slot >= sdp->sd_quota_slots)
261                 goto fail;
262
263         sdp->sd_quota_bitmap[c][o] |= 1 << b;
264
265         spin_unlock(&qd_lru_lock);
266
267         return 0;
268
269 fail:
270         qd->qd_slot_count--;
271         spin_unlock(&qd_lru_lock);
272         return -ENOSPC;
273 }
274
275 static void slot_hold(struct gfs2_quota_data *qd)
276 {
277         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
278
279         spin_lock(&qd_lru_lock);
280         gfs2_assert(sdp, qd->qd_slot_count);
281         qd->qd_slot_count++;
282         spin_unlock(&qd_lru_lock);
283 }
284
285 static void slot_put(struct gfs2_quota_data *qd)
286 {
287         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
288
289         spin_lock(&qd_lru_lock);
290         gfs2_assert(sdp, qd->qd_slot_count);
291         if (!--qd->qd_slot_count) {
292                 gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
293                 qd->qd_slot = -1;
294         }
295         spin_unlock(&qd_lru_lock);
296 }
297
298 static int bh_get(struct gfs2_quota_data *qd)
299 {
300         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
301         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
302         unsigned int block, offset;
303         struct buffer_head *bh;
304         int error;
305         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
306
307         mutex_lock(&sdp->sd_quota_mutex);
308
309         if (qd->qd_bh_count++) {
310                 mutex_unlock(&sdp->sd_quota_mutex);
311                 return 0;
312         }
313
314         block = qd->qd_slot / sdp->sd_qc_per_block;
315         offset = qd->qd_slot % sdp->sd_qc_per_block;
316
317         bh_map.b_size = 1 << ip->i_inode.i_blkbits;
318         error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
319         if (error)
320                 goto fail;
321         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
322         if (error)
323                 goto fail;
324         error = -EIO;
325         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
326                 goto fail_brelse;
327
328         qd->qd_bh = bh;
329         qd->qd_bh_qc = (struct gfs2_quota_change *)
330                 (bh->b_data + sizeof(struct gfs2_meta_header) +
331                  offset * sizeof(struct gfs2_quota_change));
332
333         mutex_unlock(&sdp->sd_quota_mutex);
334
335         return 0;
336
337 fail_brelse:
338         brelse(bh);
339 fail:
340         qd->qd_bh_count--;
341         mutex_unlock(&sdp->sd_quota_mutex);
342         return error;
343 }
344
345 static void bh_put(struct gfs2_quota_data *qd)
346 {
347         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
348
349         mutex_lock(&sdp->sd_quota_mutex);
350         gfs2_assert(sdp, qd->qd_bh_count);
351         if (!--qd->qd_bh_count) {
352                 brelse(qd->qd_bh);
353                 qd->qd_bh = NULL;
354                 qd->qd_bh_qc = NULL;
355         }
356         mutex_unlock(&sdp->sd_quota_mutex);
357 }
358
359 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
360 {
361         struct gfs2_quota_data *qd = NULL;
362         int error;
363         int found = 0;
364
365         *qdp = NULL;
366
367         if (sdp->sd_vfs->s_flags & MS_RDONLY)
368                 return 0;
369
370         spin_lock(&qd_lru_lock);
371
372         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
373                 if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
374                     !test_bit(QDF_CHANGE, &qd->qd_flags) ||
375                     qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
376                         continue;
377
378                 list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
379
380                 set_bit(QDF_LOCKED, &qd->qd_flags);
381                 gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
382                 atomic_inc(&qd->qd_count);
383                 qd->qd_change_sync = qd->qd_change;
384                 gfs2_assert_warn(sdp, qd->qd_slot_count);
385                 qd->qd_slot_count++;
386                 found = 1;
387
388                 break;
389         }
390
391         if (!found)
392                 qd = NULL;
393
394         spin_unlock(&qd_lru_lock);
395
396         if (qd) {
397                 gfs2_assert_warn(sdp, qd->qd_change_sync);
398                 error = bh_get(qd);
399                 if (error) {
400                         clear_bit(QDF_LOCKED, &qd->qd_flags);
401                         slot_put(qd);
402                         qd_put(qd);
403                         return error;
404                 }
405         }
406
407         *qdp = qd;
408
409         return 0;
410 }
411
412 static int qd_trylock(struct gfs2_quota_data *qd)
413 {
414         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
415
416         if (sdp->sd_vfs->s_flags & MS_RDONLY)
417                 return 0;
418
419         spin_lock(&qd_lru_lock);
420
421         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
422             !test_bit(QDF_CHANGE, &qd->qd_flags)) {
423                 spin_unlock(&qd_lru_lock);
424                 return 0;
425         }
426
427         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
428
429         set_bit(QDF_LOCKED, &qd->qd_flags);
430         gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
431         atomic_inc(&qd->qd_count);
432         qd->qd_change_sync = qd->qd_change;
433         gfs2_assert_warn(sdp, qd->qd_slot_count);
434         qd->qd_slot_count++;
435
436         spin_unlock(&qd_lru_lock);
437
438         gfs2_assert_warn(sdp, qd->qd_change_sync);
439         if (bh_get(qd)) {
440                 clear_bit(QDF_LOCKED, &qd->qd_flags);
441                 slot_put(qd);
442                 qd_put(qd);
443                 return 0;
444         }
445
446         return 1;
447 }
448
449 static void qd_unlock(struct gfs2_quota_data *qd)
450 {
451         gfs2_assert_warn(qd->qd_gl->gl_sbd,
452                          test_bit(QDF_LOCKED, &qd->qd_flags));
453         clear_bit(QDF_LOCKED, &qd->qd_flags);
454         bh_put(qd);
455         slot_put(qd);
456         qd_put(qd);
457 }
458
459 static int qdsb_get(struct gfs2_sbd *sdp, int user, u32 id,
460                     struct gfs2_quota_data **qdp)
461 {
462         int error;
463
464         error = qd_get(sdp, user, id, qdp);
465         if (error)
466                 return error;
467
468         error = slot_get(*qdp);
469         if (error)
470                 goto fail;
471
472         error = bh_get(*qdp);
473         if (error)
474                 goto fail_slot;
475
476         return 0;
477
478 fail_slot:
479         slot_put(*qdp);
480 fail:
481         qd_put(*qdp);
482         return error;
483 }
484
485 static void qdsb_put(struct gfs2_quota_data *qd)
486 {
487         bh_put(qd);
488         slot_put(qd);
489         qd_put(qd);
490 }
491
492 int gfs2_quota_hold(struct gfs2_inode *ip, u32 uid, u32 gid)
493 {
494         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
495         struct gfs2_alloc *al = ip->i_alloc;
496         struct gfs2_quota_data **qd = al->al_qd;
497         int error;
498
499         if (gfs2_assert_warn(sdp, !al->al_qd_num) ||
500             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
501                 return -EIO;
502
503         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
504                 return 0;
505
506         error = qdsb_get(sdp, QUOTA_USER, ip->i_inode.i_uid, qd);
507         if (error)
508                 goto out;
509         al->al_qd_num++;
510         qd++;
511
512         error = qdsb_get(sdp, QUOTA_GROUP, ip->i_inode.i_gid, qd);
513         if (error)
514                 goto out;
515         al->al_qd_num++;
516         qd++;
517
518         if (uid != NO_QUOTA_CHANGE && uid != ip->i_inode.i_uid) {
519                 error = qdsb_get(sdp, QUOTA_USER, uid, qd);
520                 if (error)
521                         goto out;
522                 al->al_qd_num++;
523                 qd++;
524         }
525
526         if (gid != NO_QUOTA_CHANGE && gid != ip->i_inode.i_gid) {
527                 error = qdsb_get(sdp, QUOTA_GROUP, gid, qd);
528                 if (error)
529                         goto out;
530                 al->al_qd_num++;
531                 qd++;
532         }
533
534 out:
535         if (error)
536                 gfs2_quota_unhold(ip);
537         return error;
538 }
539
540 void gfs2_quota_unhold(struct gfs2_inode *ip)
541 {
542         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
543         struct gfs2_alloc *al = ip->i_alloc;
544         unsigned int x;
545
546         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
547
548         for (x = 0; x < al->al_qd_num; x++) {
549                 qdsb_put(al->al_qd[x]);
550                 al->al_qd[x] = NULL;
551         }
552         al->al_qd_num = 0;
553 }
554
555 static int sort_qd(const void *a, const void *b)
556 {
557         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
558         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
559
560         if (!test_bit(QDF_USER, &qd_a->qd_flags) !=
561             !test_bit(QDF_USER, &qd_b->qd_flags)) {
562                 if (test_bit(QDF_USER, &qd_a->qd_flags))
563                         return -1;
564                 else
565                         return 1;
566         }
567         if (qd_a->qd_id < qd_b->qd_id)
568                 return -1;
569         if (qd_a->qd_id > qd_b->qd_id)
570                 return 1;
571
572         return 0;
573 }
574
575 static void do_qc(struct gfs2_quota_data *qd, s64 change)
576 {
577         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
578         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
579         struct gfs2_quota_change *qc = qd->qd_bh_qc;
580         s64 x;
581
582         mutex_lock(&sdp->sd_quota_mutex);
583         gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
584
585         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
586                 qc->qc_change = 0;
587                 qc->qc_flags = 0;
588                 if (test_bit(QDF_USER, &qd->qd_flags))
589                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
590                 qc->qc_id = cpu_to_be32(qd->qd_id);
591         }
592
593         x = be64_to_cpu(qc->qc_change) + change;
594         qc->qc_change = cpu_to_be64(x);
595
596         spin_lock(&qd_lru_lock);
597         qd->qd_change = x;
598         spin_unlock(&qd_lru_lock);
599
600         if (!x) {
601                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
602                 clear_bit(QDF_CHANGE, &qd->qd_flags);
603                 qc->qc_flags = 0;
604                 qc->qc_id = 0;
605                 slot_put(qd);
606                 qd_put(qd);
607         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
608                 qd_hold(qd);
609                 slot_hold(qd);
610         }
611
612         mutex_unlock(&sdp->sd_quota_mutex);
613 }
614
615 /**
616  * gfs2_adjust_quota - adjust record of current block usage
617  * @ip: The quota inode
618  * @loc: Offset of the entry in the quota file
619  * @change: The amount of usage change to record
620  * @qd: The quota data
621  * @fdq: The updated limits to record
622  *
623  * This function was mostly borrowed from gfs2_block_truncate_page which was
624  * in turn mostly borrowed from ext3
625  *
626  * Returns: 0 or -ve on error
627  */
628
629 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
630                              s64 change, struct gfs2_quota_data *qd,
631                              struct fs_disk_quota *fdq)
632 {
633         struct inode *inode = &ip->i_inode;
634         struct address_space *mapping = inode->i_mapping;
635         unsigned long index = loc >> PAGE_CACHE_SHIFT;
636         unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
637         unsigned blocksize, iblock, pos;
638         struct buffer_head *bh, *dibh;
639         struct page *page;
640         void *kaddr, *ptr;
641         struct gfs2_quota q, *qp;
642         int err, nbytes;
643         u64 size;
644
645         if (gfs2_is_stuffed(ip))
646                 gfs2_unstuff_dinode(ip, NULL);
647
648         memset(&q, 0, sizeof(struct gfs2_quota));
649         err = gfs2_internal_read(ip, NULL, (char *)&q, &loc, sizeof(q));
650         if (err < 0)
651                 return err;
652
653         err = -EIO;
654         qp = &q;
655         qp->qu_value = be64_to_cpu(qp->qu_value);
656         qp->qu_value += change;
657         qp->qu_value = cpu_to_be64(qp->qu_value);
658         qd->qd_qb.qb_value = qp->qu_value;
659         if (fdq) {
660                 if (fdq->d_fieldmask & FS_DQ_BSOFT) {
661                         qp->qu_warn = cpu_to_be64(fdq->d_blk_softlimit);
662                         qd->qd_qb.qb_warn = qp->qu_warn;
663                 }
664                 if (fdq->d_fieldmask & FS_DQ_BHARD) {
665                         qp->qu_limit = cpu_to_be64(fdq->d_blk_hardlimit);
666                         qd->qd_qb.qb_limit = qp->qu_limit;
667                 }
668         }
669
670         /* Write the quota into the quota file on disk */
671         ptr = qp;
672         nbytes = sizeof(struct gfs2_quota);
673 get_a_page:
674         page = grab_cache_page(mapping, index);
675         if (!page)
676                 return -ENOMEM;
677
678         blocksize = inode->i_sb->s_blocksize;
679         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
680
681         if (!page_has_buffers(page))
682                 create_empty_buffers(page, blocksize, 0);
683
684         bh = page_buffers(page);
685         pos = blocksize;
686         while (offset >= pos) {
687                 bh = bh->b_this_page;
688                 iblock++;
689                 pos += blocksize;
690         }
691
692         if (!buffer_mapped(bh)) {
693                 gfs2_block_map(inode, iblock, bh, 1);
694                 if (!buffer_mapped(bh))
695                         goto unlock_out;
696                 /* If it's a newly allocated disk block for quota, zero it */
697                 if (buffer_new(bh))
698                         zero_user(page, pos - blocksize, bh->b_size);
699         }
700
701         if (PageUptodate(page))
702                 set_buffer_uptodate(bh);
703
704         if (!buffer_uptodate(bh)) {
705                 ll_rw_block(READ_META, 1, &bh);
706                 wait_on_buffer(bh);
707                 if (!buffer_uptodate(bh))
708                         goto unlock_out;
709         }
710
711         gfs2_trans_add_bh(ip->i_gl, bh, 0);
712
713         kaddr = kmap_atomic(page, KM_USER0);
714         if (offset + sizeof(struct gfs2_quota) > PAGE_CACHE_SIZE)
715                 nbytes = PAGE_CACHE_SIZE - offset;
716         memcpy(kaddr + offset, ptr, nbytes);
717         flush_dcache_page(page);
718         kunmap_atomic(kaddr, KM_USER0);
719         unlock_page(page);
720         page_cache_release(page);
721
722         /* If quota straddles page boundary, we need to update the rest of the
723          * quota at the beginning of the next page */
724         if ((offset + sizeof(struct gfs2_quota)) > PAGE_CACHE_SIZE) {
725                 ptr = ptr + nbytes;
726                 nbytes = sizeof(struct gfs2_quota) - nbytes;
727                 offset = 0;
728                 index++;
729                 goto get_a_page;
730         }
731
732         /* Update the disk inode timestamp and size (if extended) */
733         err = gfs2_meta_inode_buffer(ip, &dibh);
734         if (err)
735                 goto out;
736
737         size = loc + sizeof(struct gfs2_quota);
738         if (size > inode->i_size) {
739                 ip->i_disksize = size;
740                 i_size_write(inode, size);
741         }
742         inode->i_mtime = inode->i_atime = CURRENT_TIME;
743         gfs2_trans_add_bh(ip->i_gl, dibh, 1);
744         gfs2_dinode_out(ip, dibh->b_data);
745         brelse(dibh);
746         mark_inode_dirty(inode);
747
748 out:
749         return err;
750 unlock_out:
751         unlock_page(page);
752         page_cache_release(page);
753         return err;
754 }
755
756 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
757 {
758         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
759         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
760         unsigned int data_blocks, ind_blocks;
761         struct gfs2_holder *ghs, i_gh;
762         unsigned int qx, x;
763         struct gfs2_quota_data *qd;
764         loff_t offset;
765         unsigned int nalloc = 0, blocks;
766         struct gfs2_alloc *al = NULL;
767         int error;
768
769         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
770                               &data_blocks, &ind_blocks);
771
772         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
773         if (!ghs)
774                 return -ENOMEM;
775
776         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
777         mutex_lock_nested(&ip->i_inode.i_mutex, I_MUTEX_QUOTA);
778         for (qx = 0; qx < num_qd; qx++) {
779                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
780                                            GL_NOCACHE, &ghs[qx]);
781                 if (error)
782                         goto out;
783         }
784
785         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
786         if (error)
787                 goto out;
788
789         for (x = 0; x < num_qd; x++) {
790                 offset = qd2offset(qda[x]);
791                 if (gfs2_write_alloc_required(ip, offset,
792                                               sizeof(struct gfs2_quota)))
793                         nalloc++;
794         }
795
796         al = gfs2_alloc_get(ip);
797         if (!al) {
798                 error = -ENOMEM;
799                 goto out_gunlock;
800         }
801         /* 
802          * 1 blk for unstuffing inode if stuffed. We add this extra
803          * block to the reservation unconditionally. If the inode
804          * doesn't need unstuffing, the block will be released to the 
805          * rgrp since it won't be allocated during the transaction
806          */
807         al->al_requested = 1;
808         /* +3 in the end for unstuffing block, inode size update block
809          * and another block in case quota straddles page boundary and 
810          * two blocks need to be updated instead of 1 */
811         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
812
813         if (nalloc)
814                 al->al_requested += nalloc * (data_blocks + ind_blocks);                
815         error = gfs2_inplace_reserve(ip);
816         if (error)
817                 goto out_alloc;
818
819         if (nalloc)
820                 blocks += al->al_rgd->rd_length + nalloc * ind_blocks + RES_STATFS;
821
822         error = gfs2_trans_begin(sdp, blocks, 0);
823         if (error)
824                 goto out_ipres;
825
826         for (x = 0; x < num_qd; x++) {
827                 qd = qda[x];
828                 offset = qd2offset(qd);
829                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
830                 if (error)
831                         goto out_end_trans;
832
833                 do_qc(qd, -qd->qd_change_sync);
834         }
835
836         error = 0;
837
838 out_end_trans:
839         gfs2_trans_end(sdp);
840 out_ipres:
841         gfs2_inplace_release(ip);
842 out_alloc:
843         gfs2_alloc_put(ip);
844 out_gunlock:
845         gfs2_glock_dq_uninit(&i_gh);
846 out:
847         while (qx--)
848                 gfs2_glock_dq_uninit(&ghs[qx]);
849         mutex_unlock(&ip->i_inode.i_mutex);
850         kfree(ghs);
851         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
852         return error;
853 }
854
855 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
856 {
857         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
858         struct gfs2_quota q;
859         struct gfs2_quota_lvb *qlvb;
860         loff_t pos;
861         int error;
862
863         memset(&q, 0, sizeof(struct gfs2_quota));
864         pos = qd2offset(qd);
865         error = gfs2_internal_read(ip, NULL, (char *)&q, &pos, sizeof(q));
866         if (error < 0)
867                 return error;
868
869         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
870         qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
871         qlvb->__pad = 0;
872         qlvb->qb_limit = q.qu_limit;
873         qlvb->qb_warn = q.qu_warn;
874         qlvb->qb_value = q.qu_value;
875         qd->qd_qb = *qlvb;
876
877         return 0;
878 }
879
880 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
881                     struct gfs2_holder *q_gh)
882 {
883         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
884         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
885         struct gfs2_holder i_gh;
886         int error;
887
888 restart:
889         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
890         if (error)
891                 return error;
892
893         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
894
895         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
896                 gfs2_glock_dq_uninit(q_gh);
897                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
898                                            GL_NOCACHE, q_gh);
899                 if (error)
900                         return error;
901
902                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
903                 if (error)
904                         goto fail;
905
906                 error = update_qd(sdp, qd);
907                 if (error)
908                         goto fail_gunlock;
909
910                 gfs2_glock_dq_uninit(&i_gh);
911                 gfs2_glock_dq_uninit(q_gh);
912                 force_refresh = 0;
913                 goto restart;
914         }
915
916         return 0;
917
918 fail_gunlock:
919         gfs2_glock_dq_uninit(&i_gh);
920 fail:
921         gfs2_glock_dq_uninit(q_gh);
922         return error;
923 }
924
925 int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
926 {
927         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
928         struct gfs2_alloc *al = ip->i_alloc;
929         unsigned int x;
930         int error = 0;
931
932         gfs2_quota_hold(ip, uid, gid);
933
934         if (capable(CAP_SYS_RESOURCE) ||
935             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
936                 return 0;
937
938         sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
939              sort_qd, NULL);
940
941         for (x = 0; x < al->al_qd_num; x++) {
942                 error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
943                 if (error)
944                         break;
945         }
946
947         if (!error)
948                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
949         else {
950                 while (x--)
951                         gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
952                 gfs2_quota_unhold(ip);
953         }
954
955         return error;
956 }
957
958 static int need_sync(struct gfs2_quota_data *qd)
959 {
960         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
961         struct gfs2_tune *gt = &sdp->sd_tune;
962         s64 value;
963         unsigned int num, den;
964         int do_sync = 1;
965
966         if (!qd->qd_qb.qb_limit)
967                 return 0;
968
969         spin_lock(&qd_lru_lock);
970         value = qd->qd_change;
971         spin_unlock(&qd_lru_lock);
972
973         spin_lock(&gt->gt_spin);
974         num = gt->gt_quota_scale_num;
975         den = gt->gt_quota_scale_den;
976         spin_unlock(&gt->gt_spin);
977
978         if (value < 0)
979                 do_sync = 0;
980         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
981                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
982                 do_sync = 0;
983         else {
984                 value *= gfs2_jindex_size(sdp) * num;
985                 value = div_s64(value, den);
986                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
987                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
988                         do_sync = 0;
989         }
990
991         return do_sync;
992 }
993
994 void gfs2_quota_unlock(struct gfs2_inode *ip)
995 {
996         struct gfs2_alloc *al = ip->i_alloc;
997         struct gfs2_quota_data *qda[4];
998         unsigned int count = 0;
999         unsigned int x;
1000
1001         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1002                 goto out;
1003
1004         for (x = 0; x < al->al_qd_num; x++) {
1005                 struct gfs2_quota_data *qd;
1006                 int sync;
1007
1008                 qd = al->al_qd[x];
1009                 sync = need_sync(qd);
1010
1011                 gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
1012
1013                 if (sync && qd_trylock(qd))
1014                         qda[count++] = qd;
1015         }
1016
1017         if (count) {
1018                 do_sync(count, qda);
1019                 for (x = 0; x < count; x++)
1020                         qd_unlock(qda[x]);
1021         }
1022
1023 out:
1024         gfs2_quota_unhold(ip);
1025 }
1026
1027 #define MAX_LINE 256
1028
1029 static int print_message(struct gfs2_quota_data *qd, char *type)
1030 {
1031         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
1032
1033         printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\n",
1034                sdp->sd_fsname, type,
1035                (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
1036                qd->qd_id);
1037
1038         return 0;
1039 }
1040
1041 int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
1042 {
1043         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1044         struct gfs2_alloc *al = ip->i_alloc;
1045         struct gfs2_quota_data *qd;
1046         s64 value;
1047         unsigned int x;
1048         int error = 0;
1049
1050         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1051                 return 0;
1052
1053         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1054                 return 0;
1055
1056         for (x = 0; x < al->al_qd_num; x++) {
1057                 qd = al->al_qd[x];
1058
1059                 if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1060                       (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
1061                         continue;
1062
1063                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1064                 spin_lock(&qd_lru_lock);
1065                 value += qd->qd_change;
1066                 spin_unlock(&qd_lru_lock);
1067
1068                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
1069                         print_message(qd, "exceeded");
1070                         quota_send_warning(test_bit(QDF_USER, &qd->qd_flags) ?
1071                                            USRQUOTA : GRPQUOTA, qd->qd_id,
1072                                            sdp->sd_vfs->s_dev, QUOTA_NL_BHARDWARN);
1073
1074                         error = -EDQUOT;
1075                         break;
1076                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
1077                            (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
1078                            time_after_eq(jiffies, qd->qd_last_warn +
1079                                          gfs2_tune_get(sdp,
1080                                                 gt_quota_warn_period) * HZ)) {
1081                         quota_send_warning(test_bit(QDF_USER, &qd->qd_flags) ?
1082                                            USRQUOTA : GRPQUOTA, qd->qd_id,
1083                                            sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1084                         error = print_message(qd, "warning");
1085                         qd->qd_last_warn = jiffies;
1086                 }
1087         }
1088
1089         return error;
1090 }
1091
1092 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1093                        u32 uid, u32 gid)
1094 {
1095         struct gfs2_alloc *al = ip->i_alloc;
1096         struct gfs2_quota_data *qd;
1097         unsigned int x;
1098
1099         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1100                 return;
1101         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1102                 return;
1103
1104         for (x = 0; x < al->al_qd_num; x++) {
1105                 qd = al->al_qd[x];
1106
1107                 if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1108                     (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
1109                         do_qc(qd, change);
1110                 }
1111         }
1112 }
1113
1114 int gfs2_quota_sync(struct super_block *sb, int type, int wait)
1115 {
1116         struct gfs2_sbd *sdp = sb->s_fs_info;
1117         struct gfs2_quota_data **qda;
1118         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
1119         unsigned int num_qd;
1120         unsigned int x;
1121         int error = 0;
1122
1123         sdp->sd_quota_sync_gen++;
1124
1125         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1126         if (!qda)
1127                 return -ENOMEM;
1128
1129         do {
1130                 num_qd = 0;
1131
1132                 for (;;) {
1133                         error = qd_fish(sdp, qda + num_qd);
1134                         if (error || !qda[num_qd])
1135                                 break;
1136                         if (++num_qd == max_qd)
1137                                 break;
1138                 }
1139
1140                 if (num_qd) {
1141                         if (!error)
1142                                 error = do_sync(num_qd, qda);
1143                         if (!error)
1144                                 for (x = 0; x < num_qd; x++)
1145                                         qda[x]->qd_sync_gen =
1146                                                 sdp->sd_quota_sync_gen;
1147
1148                         for (x = 0; x < num_qd; x++)
1149                                 qd_unlock(qda[x]);
1150                 }
1151         } while (!error && num_qd == max_qd);
1152
1153         kfree(qda);
1154
1155         return error;
1156 }
1157
1158 static int gfs2_quota_sync_timeo(struct super_block *sb, int type)
1159 {
1160         return gfs2_quota_sync(sb, type, 0);
1161 }
1162
1163 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
1164 {
1165         struct gfs2_quota_data *qd;
1166         struct gfs2_holder q_gh;
1167         int error;
1168
1169         error = qd_get(sdp, user, id, &qd);
1170         if (error)
1171                 return error;
1172
1173         error = do_glock(qd, FORCE, &q_gh);
1174         if (!error)
1175                 gfs2_glock_dq_uninit(&q_gh);
1176
1177         qd_put(qd);
1178         return error;
1179 }
1180
1181 static void gfs2_quota_change_in(struct gfs2_quota_change_host *qc, const void *buf)
1182 {
1183         const struct gfs2_quota_change *str = buf;
1184
1185         qc->qc_change = be64_to_cpu(str->qc_change);
1186         qc->qc_flags = be32_to_cpu(str->qc_flags);
1187         qc->qc_id = be32_to_cpu(str->qc_id);
1188 }
1189
1190 int gfs2_quota_init(struct gfs2_sbd *sdp)
1191 {
1192         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1193         unsigned int blocks = ip->i_disksize >> sdp->sd_sb.sb_bsize_shift;
1194         unsigned int x, slot = 0;
1195         unsigned int found = 0;
1196         u64 dblock;
1197         u32 extlen = 0;
1198         int error;
1199
1200         if (!ip->i_disksize || ip->i_disksize > (64 << 20) ||
1201             ip->i_disksize & (sdp->sd_sb.sb_bsize - 1)) {
1202                 gfs2_consist_inode(ip);
1203                 return -EIO;
1204         }
1205         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1206         sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1207
1208         error = -ENOMEM;
1209
1210         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1211                                        sizeof(unsigned char *), GFP_NOFS);
1212         if (!sdp->sd_quota_bitmap)
1213                 return error;
1214
1215         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1216                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_NOFS);
1217                 if (!sdp->sd_quota_bitmap[x])
1218                         goto fail;
1219         }
1220
1221         for (x = 0; x < blocks; x++) {
1222                 struct buffer_head *bh;
1223                 unsigned int y;
1224
1225                 if (!extlen) {
1226                         int new = 0;
1227                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1228                         if (error)
1229                                 goto fail;
1230                 }
1231                 error = -EIO;
1232                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1233                 if (!bh)
1234                         goto fail;
1235                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1236                         brelse(bh);
1237                         goto fail;
1238                 }
1239
1240                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1241                      y++, slot++) {
1242                         struct gfs2_quota_change_host qc;
1243                         struct gfs2_quota_data *qd;
1244
1245                         gfs2_quota_change_in(&qc, bh->b_data +
1246                                           sizeof(struct gfs2_meta_header) +
1247                                           y * sizeof(struct gfs2_quota_change));
1248                         if (!qc.qc_change)
1249                                 continue;
1250
1251                         error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1252                                          qc.qc_id, &qd);
1253                         if (error) {
1254                                 brelse(bh);
1255                                 goto fail;
1256                         }
1257
1258                         set_bit(QDF_CHANGE, &qd->qd_flags);
1259                         qd->qd_change = qc.qc_change;
1260                         qd->qd_slot = slot;
1261                         qd->qd_slot_count = 1;
1262
1263                         spin_lock(&qd_lru_lock);
1264                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1265                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1266                         atomic_inc(&sdp->sd_quota_count);
1267                         spin_unlock(&qd_lru_lock);
1268
1269                         found++;
1270                 }
1271
1272                 brelse(bh);
1273                 dblock++;
1274                 extlen--;
1275         }
1276
1277         if (found)
1278                 fs_info(sdp, "found %u quota changes\n", found);
1279
1280         return 0;
1281
1282 fail:
1283         gfs2_quota_cleanup(sdp);
1284         return error;
1285 }
1286
1287 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1288 {
1289         struct list_head *head = &sdp->sd_quota_list;
1290         struct gfs2_quota_data *qd;
1291         unsigned int x;
1292
1293         spin_lock(&qd_lru_lock);
1294         while (!list_empty(head)) {
1295                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1296
1297                 if (atomic_read(&qd->qd_count) > 1 ||
1298                     (atomic_read(&qd->qd_count) &&
1299                      !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1300                         list_move(&qd->qd_list, head);
1301                         spin_unlock(&qd_lru_lock);
1302                         schedule();
1303                         spin_lock(&qd_lru_lock);
1304                         continue;
1305                 }
1306
1307                 list_del(&qd->qd_list);
1308                 /* Also remove if this qd exists in the reclaim list */
1309                 if (!list_empty(&qd->qd_reclaim)) {
1310                         list_del_init(&qd->qd_reclaim);
1311                         atomic_dec(&qd_lru_count);
1312                 }
1313                 atomic_dec(&sdp->sd_quota_count);
1314                 spin_unlock(&qd_lru_lock);
1315
1316                 if (!atomic_read(&qd->qd_count)) {
1317                         gfs2_assert_warn(sdp, !qd->qd_change);
1318                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1319                 } else
1320                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1321                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1322
1323                 gfs2_glock_put(qd->qd_gl);
1324                 kmem_cache_free(gfs2_quotad_cachep, qd);
1325
1326                 spin_lock(&qd_lru_lock);
1327         }
1328         spin_unlock(&qd_lru_lock);
1329
1330         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1331
1332         if (sdp->sd_quota_bitmap) {
1333                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1334                         kfree(sdp->sd_quota_bitmap[x]);
1335                 kfree(sdp->sd_quota_bitmap);
1336         }
1337 }
1338
1339 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1340 {
1341         if (error == 0 || error == -EROFS)
1342                 return;
1343         if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1344                 fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1345 }
1346
1347 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1348                                int (*fxn)(struct super_block *sb, int type),
1349                                unsigned long t, unsigned long *timeo,
1350                                unsigned int *new_timeo)
1351 {
1352         if (t >= *timeo) {
1353                 int error = fxn(sdp->sd_vfs, 0);
1354                 quotad_error(sdp, msg, error);
1355                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1356         } else {
1357                 *timeo -= t;
1358         }
1359 }
1360
1361 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1362 {
1363         struct gfs2_inode *ip;
1364
1365         while(1) {
1366                 ip = NULL;
1367                 spin_lock(&sdp->sd_trunc_lock);
1368                 if (!list_empty(&sdp->sd_trunc_list)) {
1369                         ip = list_entry(sdp->sd_trunc_list.next,
1370                                         struct gfs2_inode, i_trunc_list);
1371                         list_del_init(&ip->i_trunc_list);
1372                 }
1373                 spin_unlock(&sdp->sd_trunc_lock);
1374                 if (ip == NULL)
1375                         return;
1376                 gfs2_glock_finish_truncate(ip);
1377         }
1378 }
1379
1380 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1381         if (!sdp->sd_statfs_force_sync) {
1382                 sdp->sd_statfs_force_sync = 1;
1383                 wake_up(&sdp->sd_quota_wait);
1384         }
1385 }
1386
1387
1388 /**
1389  * gfs2_quotad - Write cached quota changes into the quota file
1390  * @sdp: Pointer to GFS2 superblock
1391  *
1392  */
1393
1394 int gfs2_quotad(void *data)
1395 {
1396         struct gfs2_sbd *sdp = data;
1397         struct gfs2_tune *tune = &sdp->sd_tune;
1398         unsigned long statfs_timeo = 0;
1399         unsigned long quotad_timeo = 0;
1400         unsigned long t = 0;
1401         DEFINE_WAIT(wait);
1402         int empty;
1403
1404         while (!kthread_should_stop()) {
1405
1406                 /* Update the master statfs file */
1407                 if (sdp->sd_statfs_force_sync) {
1408                         int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1409                         quotad_error(sdp, "statfs", error);
1410                         statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1411                 }
1412                 else
1413                         quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1414                                            &statfs_timeo,
1415                                            &tune->gt_statfs_quantum);
1416
1417                 /* Update quota file */
1418                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync_timeo, t,
1419                                    &quotad_timeo, &tune->gt_quota_quantum);
1420
1421                 /* Check for & recover partially truncated inodes */
1422                 quotad_check_trunc_list(sdp);
1423
1424                 if (freezing(current))
1425                         refrigerator();
1426                 t = min(quotad_timeo, statfs_timeo);
1427
1428                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1429                 spin_lock(&sdp->sd_trunc_lock);
1430                 empty = list_empty(&sdp->sd_trunc_list);
1431                 spin_unlock(&sdp->sd_trunc_lock);
1432                 if (empty && !sdp->sd_statfs_force_sync)
1433                         t -= schedule_timeout(t);
1434                 else
1435                         t = 0;
1436                 finish_wait(&sdp->sd_quota_wait, &wait);
1437         }
1438
1439         return 0;
1440 }
1441
1442 static int gfs2_quota_get_xstate(struct super_block *sb,
1443                                  struct fs_quota_stat *fqs)
1444 {
1445         struct gfs2_sbd *sdp = sb->s_fs_info;
1446
1447         memset(fqs, 0, sizeof(struct fs_quota_stat));
1448         fqs->qs_version = FS_QSTAT_VERSION;
1449
1450         switch (sdp->sd_args.ar_quota) {
1451         case GFS2_QUOTA_ON:
1452                 fqs->qs_flags |= (FS_QUOTA_UDQ_ENFD | FS_QUOTA_GDQ_ENFD);
1453                 /*FALLTHRU*/
1454         case GFS2_QUOTA_ACCOUNT:
1455                 fqs->qs_flags |= (FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT);
1456                 break;
1457         case GFS2_QUOTA_OFF:
1458                 break;
1459         }
1460
1461         if (sdp->sd_quota_inode) {
1462                 fqs->qs_uquota.qfs_ino = GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1463                 fqs->qs_uquota.qfs_nblks = sdp->sd_quota_inode->i_blocks;
1464         }
1465         fqs->qs_uquota.qfs_nextents = 1; /* unsupported */
1466         fqs->qs_gquota = fqs->qs_uquota; /* its the same inode in both cases */
1467         fqs->qs_incoredqs = atomic_read(&qd_lru_count);
1468         return 0;
1469 }
1470
1471 static int gfs2_get_dqblk(struct super_block *sb, int type, qid_t id,
1472                           struct fs_disk_quota *fdq)
1473 {
1474         struct gfs2_sbd *sdp = sb->s_fs_info;
1475         struct gfs2_quota_lvb *qlvb;
1476         struct gfs2_quota_data *qd;
1477         struct gfs2_holder q_gh;
1478         int error;
1479
1480         memset(fdq, 0, sizeof(struct fs_disk_quota));
1481
1482         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1483                 return -ESRCH; /* Crazy XFS error code */
1484
1485         if (type == USRQUOTA)
1486                 type = QUOTA_USER;
1487         else if (type == GRPQUOTA)
1488                 type = QUOTA_GROUP;
1489         else
1490                 return -EINVAL;
1491
1492         error = qd_get(sdp, type, id, &qd);
1493         if (error)
1494                 return error;
1495         error = do_glock(qd, FORCE, &q_gh);
1496         if (error)
1497                 goto out;
1498
1499         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
1500         fdq->d_version = FS_DQUOT_VERSION;
1501         fdq->d_flags = (type == QUOTA_USER) ? FS_USER_QUOTA : FS_GROUP_QUOTA;
1502         fdq->d_id = id;
1503         fdq->d_blk_hardlimit = be64_to_cpu(qlvb->qb_limit);
1504         fdq->d_blk_softlimit = be64_to_cpu(qlvb->qb_warn);
1505         fdq->d_bcount = be64_to_cpu(qlvb->qb_value);
1506
1507         gfs2_glock_dq_uninit(&q_gh);
1508 out:
1509         qd_put(qd);
1510         return error;
1511 }
1512
1513 /* GFS2 only supports a subset of the XFS fields */
1514 #define GFS2_FIELDMASK (FS_DQ_BSOFT|FS_DQ_BHARD)
1515
1516 static int gfs2_set_dqblk(struct super_block *sb, int type, qid_t id,
1517                           struct fs_disk_quota *fdq)
1518 {
1519         struct gfs2_sbd *sdp = sb->s_fs_info;
1520         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1521         struct gfs2_quota_data *qd;
1522         struct gfs2_holder q_gh, i_gh;
1523         unsigned int data_blocks, ind_blocks;
1524         unsigned int blocks = 0;
1525         int alloc_required;
1526         struct gfs2_alloc *al;
1527         loff_t offset;
1528         int error;
1529
1530         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1531                 return -ESRCH; /* Crazy XFS error code */
1532
1533         switch(type) {
1534         case USRQUOTA:
1535                 type = QUOTA_USER;
1536                 if (fdq->d_flags != FS_USER_QUOTA)
1537                         return -EINVAL;
1538                 break;
1539         case GRPQUOTA:
1540                 type = QUOTA_GROUP;
1541                 if (fdq->d_flags != FS_GROUP_QUOTA)
1542                         return -EINVAL;
1543                 break;
1544         default:
1545                 return -EINVAL;
1546         }
1547
1548         if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1549                 return -EINVAL;
1550         if (fdq->d_id != id)
1551                 return -EINVAL;
1552
1553         error = qd_get(sdp, type, id, &qd);
1554         if (error)
1555                 return error;
1556
1557         mutex_lock(&ip->i_inode.i_mutex);
1558         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1559         if (error)
1560                 goto out_put;
1561         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1562         if (error)
1563                 goto out_q;
1564
1565         /* Check for existing entry, if none then alloc new blocks */
1566         error = update_qd(sdp, qd);
1567         if (error)
1568                 goto out_i;
1569
1570         /* If nothing has changed, this is a no-op */
1571         if ((fdq->d_fieldmask & FS_DQ_BSOFT) &&
1572             (fdq->d_blk_softlimit == be64_to_cpu(qd->qd_qb.qb_warn)))
1573                 fdq->d_fieldmask ^= FS_DQ_BSOFT;
1574         if ((fdq->d_fieldmask & FS_DQ_BHARD) &&
1575             (fdq->d_blk_hardlimit == be64_to_cpu(qd->qd_qb.qb_limit)))
1576                 fdq->d_fieldmask ^= FS_DQ_BHARD;
1577         if (fdq->d_fieldmask == 0)
1578                 goto out_i;
1579
1580         offset = qd2offset(qd);
1581         alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1582         if (alloc_required) {
1583                 al = gfs2_alloc_get(ip);
1584                 if (al == NULL)
1585                         goto out_i;
1586                 gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1587                                        &data_blocks, &ind_blocks);
1588                 blocks = al->al_requested = 1 + data_blocks + ind_blocks;
1589                 error = gfs2_inplace_reserve(ip);
1590                 if (error)
1591                         goto out_alloc;
1592         }
1593
1594         error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 1, 0);
1595         if (error)
1596                 goto out_release;
1597
1598         /* Apply changes */
1599         error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1600
1601         gfs2_trans_end(sdp);
1602 out_release:
1603         if (alloc_required) {
1604                 gfs2_inplace_release(ip);
1605 out_alloc:
1606                 gfs2_alloc_put(ip);
1607         }
1608 out_i:
1609         gfs2_glock_dq_uninit(&i_gh);
1610 out_q:
1611         gfs2_glock_dq_uninit(&q_gh);
1612 out_put:
1613         mutex_unlock(&ip->i_inode.i_mutex);
1614         qd_put(qd);
1615         return error;
1616 }
1617
1618 const struct quotactl_ops gfs2_quotactl_ops = {
1619         .quota_sync     = gfs2_quota_sync,
1620         .get_xstate     = gfs2_quota_get_xstate,
1621         .get_dqblk      = gfs2_get_dqblk,
1622         .set_dqblk      = gfs2_set_dqblk,
1623 };
1624