vfs: introduce noop_llseek()
[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(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                         memset(bh->b_data, 0, bh->b_size);
699                         set_buffer_uptodate(bh);
700                 }
701         }
702
703         if (PageUptodate(page))
704                 set_buffer_uptodate(bh);
705
706         if (!buffer_uptodate(bh)) {
707                 ll_rw_block(READ_META, 1, &bh);
708                 wait_on_buffer(bh);
709                 if (!buffer_uptodate(bh))
710                         goto unlock_out;
711         }
712
713         gfs2_trans_add_bh(ip->i_gl, bh, 0);
714
715         kaddr = kmap_atomic(page, KM_USER0);
716         if (offset + sizeof(struct gfs2_quota) > PAGE_CACHE_SIZE)
717                 nbytes = PAGE_CACHE_SIZE - offset;
718         memcpy(kaddr + offset, ptr, nbytes);
719         flush_dcache_page(page);
720         kunmap_atomic(kaddr, KM_USER0);
721         unlock_page(page);
722         page_cache_release(page);
723
724         /* If quota straddles page boundary, we need to update the rest of the
725          * quota at the beginning of the next page */
726         if (offset != 0) { /* first page, offset is closer to PAGE_CACHE_SIZE */
727                 ptr = ptr + nbytes;
728                 nbytes = sizeof(struct gfs2_quota) - nbytes;
729                 offset = 0;
730                 index++;
731                 goto get_a_page;
732         }
733
734         /* Update the disk inode timestamp and size (if extended) */
735         err = gfs2_meta_inode_buffer(ip, &dibh);
736         if (err)
737                 goto out;
738
739         size = loc + sizeof(struct gfs2_quota);
740         if (size > inode->i_size) {
741                 ip->i_disksize = size;
742                 i_size_write(inode, size);
743         }
744         inode->i_mtime = inode->i_atime = CURRENT_TIME;
745         gfs2_trans_add_bh(ip->i_gl, dibh, 1);
746         gfs2_dinode_out(ip, dibh->b_data);
747         brelse(dibh);
748         mark_inode_dirty(inode);
749
750 out:
751         return err;
752 unlock_out:
753         unlock_page(page);
754         page_cache_release(page);
755         return err;
756 }
757
758 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
759 {
760         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
761         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
762         unsigned int data_blocks, ind_blocks;
763         struct gfs2_holder *ghs, i_gh;
764         unsigned int qx, x;
765         struct gfs2_quota_data *qd;
766         loff_t offset;
767         unsigned int nalloc = 0, blocks;
768         struct gfs2_alloc *al = NULL;
769         int error;
770
771         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
772                               &data_blocks, &ind_blocks);
773
774         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
775         if (!ghs)
776                 return -ENOMEM;
777
778         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
779         mutex_lock_nested(&ip->i_inode.i_mutex, I_MUTEX_QUOTA);
780         for (qx = 0; qx < num_qd; qx++) {
781                 error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
782                                            GL_NOCACHE, &ghs[qx]);
783                 if (error)
784                         goto out;
785         }
786
787         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
788         if (error)
789                 goto out;
790
791         for (x = 0; x < num_qd; x++) {
792                 int alloc_required;
793
794                 offset = qd2offset(qda[x]);
795                 error = gfs2_write_alloc_required(ip, offset,
796                                                   sizeof(struct gfs2_quota),
797                                                   &alloc_required);
798                 if (error)
799                         goto out_gunlock;
800                 if (alloc_required)
801                         nalloc++;
802         }
803
804         al = gfs2_alloc_get(ip);
805         if (!al) {
806                 error = -ENOMEM;
807                 goto out_gunlock;
808         }
809         /* 
810          * 1 blk for unstuffing inode if stuffed. We add this extra
811          * block to the reservation unconditionally. If the inode
812          * doesn't need unstuffing, the block will be released to the 
813          * rgrp since it won't be allocated during the transaction
814          */
815         al->al_requested = 1;
816         /* +3 in the end for unstuffing block, inode size update block
817          * and another block in case quota straddles page boundary and 
818          * two blocks need to be updated instead of 1 */
819         blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
820
821         if (nalloc)
822                 al->al_requested += nalloc * (data_blocks + ind_blocks);                
823         error = gfs2_inplace_reserve(ip);
824         if (error)
825                 goto out_alloc;
826
827         if (nalloc)
828                 blocks += al->al_rgd->rd_length + nalloc * ind_blocks + RES_STATFS;
829
830         error = gfs2_trans_begin(sdp, blocks, 0);
831         if (error)
832                 goto out_ipres;
833
834         for (x = 0; x < num_qd; x++) {
835                 qd = qda[x];
836                 offset = qd2offset(qd);
837                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
838                 if (error)
839                         goto out_end_trans;
840
841                 do_qc(qd, -qd->qd_change_sync);
842         }
843
844         error = 0;
845
846 out_end_trans:
847         gfs2_trans_end(sdp);
848 out_ipres:
849         gfs2_inplace_release(ip);
850 out_alloc:
851         gfs2_alloc_put(ip);
852 out_gunlock:
853         gfs2_glock_dq_uninit(&i_gh);
854 out:
855         while (qx--)
856                 gfs2_glock_dq_uninit(&ghs[qx]);
857         mutex_unlock(&ip->i_inode.i_mutex);
858         kfree(ghs);
859         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
860         return error;
861 }
862
863 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
864 {
865         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
866         struct gfs2_quota q;
867         struct gfs2_quota_lvb *qlvb;
868         loff_t pos;
869         int error;
870
871         memset(&q, 0, sizeof(struct gfs2_quota));
872         pos = qd2offset(qd);
873         error = gfs2_internal_read(ip, NULL, (char *)&q, &pos, sizeof(q));
874         if (error < 0)
875                 return error;
876
877         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
878         qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
879         qlvb->__pad = 0;
880         qlvb->qb_limit = q.qu_limit;
881         qlvb->qb_warn = q.qu_warn;
882         qlvb->qb_value = q.qu_value;
883         qd->qd_qb = *qlvb;
884
885         return 0;
886 }
887
888 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
889                     struct gfs2_holder *q_gh)
890 {
891         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
892         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
893         struct gfs2_holder i_gh;
894         int error;
895
896 restart:
897         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
898         if (error)
899                 return error;
900
901         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
902
903         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
904                 gfs2_glock_dq_uninit(q_gh);
905                 error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
906                                            GL_NOCACHE, q_gh);
907                 if (error)
908                         return error;
909
910                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
911                 if (error)
912                         goto fail;
913
914                 error = update_qd(sdp, qd);
915                 if (error)
916                         goto fail_gunlock;
917
918                 gfs2_glock_dq_uninit(&i_gh);
919                 gfs2_glock_dq_uninit(q_gh);
920                 force_refresh = 0;
921                 goto restart;
922         }
923
924         return 0;
925
926 fail_gunlock:
927         gfs2_glock_dq_uninit(&i_gh);
928 fail:
929         gfs2_glock_dq_uninit(q_gh);
930         return error;
931 }
932
933 int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
934 {
935         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
936         struct gfs2_alloc *al = ip->i_alloc;
937         unsigned int x;
938         int error = 0;
939
940         gfs2_quota_hold(ip, uid, gid);
941
942         if (capable(CAP_SYS_RESOURCE) ||
943             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
944                 return 0;
945
946         sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
947              sort_qd, NULL);
948
949         for (x = 0; x < al->al_qd_num; x++) {
950                 error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
951                 if (error)
952                         break;
953         }
954
955         if (!error)
956                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
957         else {
958                 while (x--)
959                         gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
960                 gfs2_quota_unhold(ip);
961         }
962
963         return error;
964 }
965
966 static int need_sync(struct gfs2_quota_data *qd)
967 {
968         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
969         struct gfs2_tune *gt = &sdp->sd_tune;
970         s64 value;
971         unsigned int num, den;
972         int do_sync = 1;
973
974         if (!qd->qd_qb.qb_limit)
975                 return 0;
976
977         spin_lock(&qd_lru_lock);
978         value = qd->qd_change;
979         spin_unlock(&qd_lru_lock);
980
981         spin_lock(&gt->gt_spin);
982         num = gt->gt_quota_scale_num;
983         den = gt->gt_quota_scale_den;
984         spin_unlock(&gt->gt_spin);
985
986         if (value < 0)
987                 do_sync = 0;
988         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
989                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
990                 do_sync = 0;
991         else {
992                 value *= gfs2_jindex_size(sdp) * num;
993                 value = div_s64(value, den);
994                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
995                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
996                         do_sync = 0;
997         }
998
999         return do_sync;
1000 }
1001
1002 void gfs2_quota_unlock(struct gfs2_inode *ip)
1003 {
1004         struct gfs2_alloc *al = ip->i_alloc;
1005         struct gfs2_quota_data *qda[4];
1006         unsigned int count = 0;
1007         unsigned int x;
1008
1009         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1010                 goto out;
1011
1012         for (x = 0; x < al->al_qd_num; x++) {
1013                 struct gfs2_quota_data *qd;
1014                 int sync;
1015
1016                 qd = al->al_qd[x];
1017                 sync = need_sync(qd);
1018
1019                 gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
1020
1021                 if (sync && qd_trylock(qd))
1022                         qda[count++] = qd;
1023         }
1024
1025         if (count) {
1026                 do_sync(count, qda);
1027                 for (x = 0; x < count; x++)
1028                         qd_unlock(qda[x]);
1029         }
1030
1031 out:
1032         gfs2_quota_unhold(ip);
1033 }
1034
1035 #define MAX_LINE 256
1036
1037 static int print_message(struct gfs2_quota_data *qd, char *type)
1038 {
1039         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
1040
1041         printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\n",
1042                sdp->sd_fsname, type,
1043                (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
1044                qd->qd_id);
1045
1046         return 0;
1047 }
1048
1049 int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
1050 {
1051         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1052         struct gfs2_alloc *al = ip->i_alloc;
1053         struct gfs2_quota_data *qd;
1054         s64 value;
1055         unsigned int x;
1056         int error = 0;
1057
1058         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1059                 return 0;
1060
1061         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1062                 return 0;
1063
1064         for (x = 0; x < al->al_qd_num; x++) {
1065                 qd = al->al_qd[x];
1066
1067                 if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1068                       (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
1069                         continue;
1070
1071                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1072                 spin_lock(&qd_lru_lock);
1073                 value += qd->qd_change;
1074                 spin_unlock(&qd_lru_lock);
1075
1076                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
1077                         print_message(qd, "exceeded");
1078                         quota_send_warning(test_bit(QDF_USER, &qd->qd_flags) ?
1079                                            USRQUOTA : GRPQUOTA, qd->qd_id,
1080                                            sdp->sd_vfs->s_dev, QUOTA_NL_BHARDWARN);
1081
1082                         error = -EDQUOT;
1083                         break;
1084                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
1085                            (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
1086                            time_after_eq(jiffies, qd->qd_last_warn +
1087                                          gfs2_tune_get(sdp,
1088                                                 gt_quota_warn_period) * HZ)) {
1089                         quota_send_warning(test_bit(QDF_USER, &qd->qd_flags) ?
1090                                            USRQUOTA : GRPQUOTA, qd->qd_id,
1091                                            sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1092                         error = print_message(qd, "warning");
1093                         qd->qd_last_warn = jiffies;
1094                 }
1095         }
1096
1097         return error;
1098 }
1099
1100 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1101                        u32 uid, u32 gid)
1102 {
1103         struct gfs2_alloc *al = ip->i_alloc;
1104         struct gfs2_quota_data *qd;
1105         unsigned int x;
1106
1107         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1108                 return;
1109         if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1110                 return;
1111
1112         for (x = 0; x < al->al_qd_num; x++) {
1113                 qd = al->al_qd[x];
1114
1115                 if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1116                     (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
1117                         do_qc(qd, change);
1118                 }
1119         }
1120 }
1121
1122 int gfs2_quota_sync(struct super_block *sb, int type, int wait)
1123 {
1124         struct gfs2_sbd *sdp = sb->s_fs_info;
1125         struct gfs2_quota_data **qda;
1126         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
1127         unsigned int num_qd;
1128         unsigned int x;
1129         int error = 0;
1130
1131         sdp->sd_quota_sync_gen++;
1132
1133         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1134         if (!qda)
1135                 return -ENOMEM;
1136
1137         do {
1138                 num_qd = 0;
1139
1140                 for (;;) {
1141                         error = qd_fish(sdp, qda + num_qd);
1142                         if (error || !qda[num_qd])
1143                                 break;
1144                         if (++num_qd == max_qd)
1145                                 break;
1146                 }
1147
1148                 if (num_qd) {
1149                         if (!error)
1150                                 error = do_sync(num_qd, qda);
1151                         if (!error)
1152                                 for (x = 0; x < num_qd; x++)
1153                                         qda[x]->qd_sync_gen =
1154                                                 sdp->sd_quota_sync_gen;
1155
1156                         for (x = 0; x < num_qd; x++)
1157                                 qd_unlock(qda[x]);
1158                 }
1159         } while (!error && num_qd == max_qd);
1160
1161         kfree(qda);
1162
1163         return error;
1164 }
1165
1166 static int gfs2_quota_sync_timeo(struct super_block *sb, int type)
1167 {
1168         return gfs2_quota_sync(sb, type, 0);
1169 }
1170
1171 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
1172 {
1173         struct gfs2_quota_data *qd;
1174         struct gfs2_holder q_gh;
1175         int error;
1176
1177         error = qd_get(sdp, user, id, &qd);
1178         if (error)
1179                 return error;
1180
1181         error = do_glock(qd, FORCE, &q_gh);
1182         if (!error)
1183                 gfs2_glock_dq_uninit(&q_gh);
1184
1185         qd_put(qd);
1186         return error;
1187 }
1188
1189 static void gfs2_quota_change_in(struct gfs2_quota_change_host *qc, const void *buf)
1190 {
1191         const struct gfs2_quota_change *str = buf;
1192
1193         qc->qc_change = be64_to_cpu(str->qc_change);
1194         qc->qc_flags = be32_to_cpu(str->qc_flags);
1195         qc->qc_id = be32_to_cpu(str->qc_id);
1196 }
1197
1198 int gfs2_quota_init(struct gfs2_sbd *sdp)
1199 {
1200         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1201         unsigned int blocks = ip->i_disksize >> sdp->sd_sb.sb_bsize_shift;
1202         unsigned int x, slot = 0;
1203         unsigned int found = 0;
1204         u64 dblock;
1205         u32 extlen = 0;
1206         int error;
1207
1208         if (!ip->i_disksize || ip->i_disksize > (64 << 20) ||
1209             ip->i_disksize & (sdp->sd_sb.sb_bsize - 1)) {
1210                 gfs2_consist_inode(ip);
1211                 return -EIO;
1212         }
1213         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1214         sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1215
1216         error = -ENOMEM;
1217
1218         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1219                                        sizeof(unsigned char *), GFP_NOFS);
1220         if (!sdp->sd_quota_bitmap)
1221                 return error;
1222
1223         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1224                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_NOFS);
1225                 if (!sdp->sd_quota_bitmap[x])
1226                         goto fail;
1227         }
1228
1229         for (x = 0; x < blocks; x++) {
1230                 struct buffer_head *bh;
1231                 unsigned int y;
1232
1233                 if (!extlen) {
1234                         int new = 0;
1235                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1236                         if (error)
1237                                 goto fail;
1238                 }
1239                 error = -EIO;
1240                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1241                 if (!bh)
1242                         goto fail;
1243                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1244                         brelse(bh);
1245                         goto fail;
1246                 }
1247
1248                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1249                      y++, slot++) {
1250                         struct gfs2_quota_change_host qc;
1251                         struct gfs2_quota_data *qd;
1252
1253                         gfs2_quota_change_in(&qc, bh->b_data +
1254                                           sizeof(struct gfs2_meta_header) +
1255                                           y * sizeof(struct gfs2_quota_change));
1256                         if (!qc.qc_change)
1257                                 continue;
1258
1259                         error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1260                                          qc.qc_id, &qd);
1261                         if (error) {
1262                                 brelse(bh);
1263                                 goto fail;
1264                         }
1265
1266                         set_bit(QDF_CHANGE, &qd->qd_flags);
1267                         qd->qd_change = qc.qc_change;
1268                         qd->qd_slot = slot;
1269                         qd->qd_slot_count = 1;
1270
1271                         spin_lock(&qd_lru_lock);
1272                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1273                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1274                         atomic_inc(&sdp->sd_quota_count);
1275                         spin_unlock(&qd_lru_lock);
1276
1277                         found++;
1278                 }
1279
1280                 brelse(bh);
1281                 dblock++;
1282                 extlen--;
1283         }
1284
1285         if (found)
1286                 fs_info(sdp, "found %u quota changes\n", found);
1287
1288         return 0;
1289
1290 fail:
1291         gfs2_quota_cleanup(sdp);
1292         return error;
1293 }
1294
1295 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1296 {
1297         struct list_head *head = &sdp->sd_quota_list;
1298         struct gfs2_quota_data *qd;
1299         unsigned int x;
1300
1301         spin_lock(&qd_lru_lock);
1302         while (!list_empty(head)) {
1303                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1304
1305                 if (atomic_read(&qd->qd_count) > 1 ||
1306                     (atomic_read(&qd->qd_count) &&
1307                      !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1308                         list_move(&qd->qd_list, head);
1309                         spin_unlock(&qd_lru_lock);
1310                         schedule();
1311                         spin_lock(&qd_lru_lock);
1312                         continue;
1313                 }
1314
1315                 list_del(&qd->qd_list);
1316                 /* Also remove if this qd exists in the reclaim list */
1317                 if (!list_empty(&qd->qd_reclaim)) {
1318                         list_del_init(&qd->qd_reclaim);
1319                         atomic_dec(&qd_lru_count);
1320                 }
1321                 atomic_dec(&sdp->sd_quota_count);
1322                 spin_unlock(&qd_lru_lock);
1323
1324                 if (!atomic_read(&qd->qd_count)) {
1325                         gfs2_assert_warn(sdp, !qd->qd_change);
1326                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1327                 } else
1328                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1329                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1330
1331                 gfs2_glock_put(qd->qd_gl);
1332                 kmem_cache_free(gfs2_quotad_cachep, qd);
1333
1334                 spin_lock(&qd_lru_lock);
1335         }
1336         spin_unlock(&qd_lru_lock);
1337
1338         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1339
1340         if (sdp->sd_quota_bitmap) {
1341                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1342                         kfree(sdp->sd_quota_bitmap[x]);
1343                 kfree(sdp->sd_quota_bitmap);
1344         }
1345 }
1346
1347 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1348 {
1349         if (error == 0 || error == -EROFS)
1350                 return;
1351         if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1352                 fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1353 }
1354
1355 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1356                                int (*fxn)(struct super_block *sb, int type),
1357                                unsigned long t, unsigned long *timeo,
1358                                unsigned int *new_timeo)
1359 {
1360         if (t >= *timeo) {
1361                 int error = fxn(sdp->sd_vfs, 0);
1362                 quotad_error(sdp, msg, error);
1363                 *timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1364         } else {
1365                 *timeo -= t;
1366         }
1367 }
1368
1369 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1370 {
1371         struct gfs2_inode *ip;
1372
1373         while(1) {
1374                 ip = NULL;
1375                 spin_lock(&sdp->sd_trunc_lock);
1376                 if (!list_empty(&sdp->sd_trunc_list)) {
1377                         ip = list_entry(sdp->sd_trunc_list.next,
1378                                         struct gfs2_inode, i_trunc_list);
1379                         list_del_init(&ip->i_trunc_list);
1380                 }
1381                 spin_unlock(&sdp->sd_trunc_lock);
1382                 if (ip == NULL)
1383                         return;
1384                 gfs2_glock_finish_truncate(ip);
1385         }
1386 }
1387
1388 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1389         if (!sdp->sd_statfs_force_sync) {
1390                 sdp->sd_statfs_force_sync = 1;
1391                 wake_up(&sdp->sd_quota_wait);
1392         }
1393 }
1394
1395
1396 /**
1397  * gfs2_quotad - Write cached quota changes into the quota file
1398  * @sdp: Pointer to GFS2 superblock
1399  *
1400  */
1401
1402 int gfs2_quotad(void *data)
1403 {
1404         struct gfs2_sbd *sdp = data;
1405         struct gfs2_tune *tune = &sdp->sd_tune;
1406         unsigned long statfs_timeo = 0;
1407         unsigned long quotad_timeo = 0;
1408         unsigned long t = 0;
1409         DEFINE_WAIT(wait);
1410         int empty;
1411
1412         while (!kthread_should_stop()) {
1413
1414                 /* Update the master statfs file */
1415                 if (sdp->sd_statfs_force_sync) {
1416                         int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1417                         quotad_error(sdp, "statfs", error);
1418                         statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1419                 }
1420                 else
1421                         quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1422                                            &statfs_timeo,
1423                                            &tune->gt_statfs_quantum);
1424
1425                 /* Update quota file */
1426                 quotad_check_timeo(sdp, "sync", gfs2_quota_sync_timeo, t,
1427                                    &quotad_timeo, &tune->gt_quota_quantum);
1428
1429                 /* Check for & recover partially truncated inodes */
1430                 quotad_check_trunc_list(sdp);
1431
1432                 if (freezing(current))
1433                         refrigerator();
1434                 t = min(quotad_timeo, statfs_timeo);
1435
1436                 prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1437                 spin_lock(&sdp->sd_trunc_lock);
1438                 empty = list_empty(&sdp->sd_trunc_list);
1439                 spin_unlock(&sdp->sd_trunc_lock);
1440                 if (empty && !sdp->sd_statfs_force_sync)
1441                         t -= schedule_timeout(t);
1442                 else
1443                         t = 0;
1444                 finish_wait(&sdp->sd_quota_wait, &wait);
1445         }
1446
1447         return 0;
1448 }
1449
1450 static int gfs2_quota_get_xstate(struct super_block *sb,
1451                                  struct fs_quota_stat *fqs)
1452 {
1453         struct gfs2_sbd *sdp = sb->s_fs_info;
1454
1455         memset(fqs, 0, sizeof(struct fs_quota_stat));
1456         fqs->qs_version = FS_QSTAT_VERSION;
1457
1458         switch (sdp->sd_args.ar_quota) {
1459         case GFS2_QUOTA_ON:
1460                 fqs->qs_flags |= (XFS_QUOTA_UDQ_ENFD | XFS_QUOTA_GDQ_ENFD);
1461                 /*FALLTHRU*/
1462         case GFS2_QUOTA_ACCOUNT:
1463                 fqs->qs_flags |= (XFS_QUOTA_UDQ_ACCT | XFS_QUOTA_GDQ_ACCT);
1464                 break;
1465         case GFS2_QUOTA_OFF:
1466                 break;
1467         }
1468
1469         if (sdp->sd_quota_inode) {
1470                 fqs->qs_uquota.qfs_ino = GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1471                 fqs->qs_uquota.qfs_nblks = sdp->sd_quota_inode->i_blocks;
1472         }
1473         fqs->qs_uquota.qfs_nextents = 1; /* unsupported */
1474         fqs->qs_gquota = fqs->qs_uquota; /* its the same inode in both cases */
1475         fqs->qs_incoredqs = atomic_read(&qd_lru_count);
1476         return 0;
1477 }
1478
1479 static int gfs2_get_dqblk(struct super_block *sb, int type, qid_t id,
1480                           struct fs_disk_quota *fdq)
1481 {
1482         struct gfs2_sbd *sdp = sb->s_fs_info;
1483         struct gfs2_quota_lvb *qlvb;
1484         struct gfs2_quota_data *qd;
1485         struct gfs2_holder q_gh;
1486         int error;
1487
1488         memset(fdq, 0, sizeof(struct fs_disk_quota));
1489
1490         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1491                 return -ESRCH; /* Crazy XFS error code */
1492
1493         if (type == USRQUOTA)
1494                 type = QUOTA_USER;
1495         else if (type == GRPQUOTA)
1496                 type = QUOTA_GROUP;
1497         else
1498                 return -EINVAL;
1499
1500         error = qd_get(sdp, type, id, &qd);
1501         if (error)
1502                 return error;
1503         error = do_glock(qd, FORCE, &q_gh);
1504         if (error)
1505                 goto out;
1506
1507         qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
1508         fdq->d_version = FS_DQUOT_VERSION;
1509         fdq->d_flags = (type == QUOTA_USER) ? XFS_USER_QUOTA : XFS_GROUP_QUOTA;
1510         fdq->d_id = id;
1511         fdq->d_blk_hardlimit = be64_to_cpu(qlvb->qb_limit);
1512         fdq->d_blk_softlimit = be64_to_cpu(qlvb->qb_warn);
1513         fdq->d_bcount = be64_to_cpu(qlvb->qb_value);
1514
1515         gfs2_glock_dq_uninit(&q_gh);
1516 out:
1517         qd_put(qd);
1518         return error;
1519 }
1520
1521 /* GFS2 only supports a subset of the XFS fields */
1522 #define GFS2_FIELDMASK (FS_DQ_BSOFT|FS_DQ_BHARD)
1523
1524 static int gfs2_set_dqblk(struct super_block *sb, int type, qid_t id,
1525                           struct fs_disk_quota *fdq)
1526 {
1527         struct gfs2_sbd *sdp = sb->s_fs_info;
1528         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1529         struct gfs2_quota_data *qd;
1530         struct gfs2_holder q_gh, i_gh;
1531         unsigned int data_blocks, ind_blocks;
1532         unsigned int blocks = 0;
1533         int alloc_required;
1534         struct gfs2_alloc *al;
1535         loff_t offset;
1536         int error;
1537
1538         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1539                 return -ESRCH; /* Crazy XFS error code */
1540
1541         switch(type) {
1542         case USRQUOTA:
1543                 type = QUOTA_USER;
1544                 if (fdq->d_flags != XFS_USER_QUOTA)
1545                         return -EINVAL;
1546                 break;
1547         case GRPQUOTA:
1548                 type = QUOTA_GROUP;
1549                 if (fdq->d_flags != XFS_GROUP_QUOTA)
1550                         return -EINVAL;
1551                 break;
1552         default:
1553                 return -EINVAL;
1554         }
1555
1556         if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1557                 return -EINVAL;
1558         if (fdq->d_id != id)
1559                 return -EINVAL;
1560
1561         error = qd_get(sdp, type, id, &qd);
1562         if (error)
1563                 return error;
1564
1565         mutex_lock(&ip->i_inode.i_mutex);
1566         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1567         if (error)
1568                 goto out_put;
1569         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1570         if (error)
1571                 goto out_q;
1572
1573         /* Check for existing entry, if none then alloc new blocks */
1574         error = update_qd(sdp, qd);
1575         if (error)
1576                 goto out_i;
1577
1578         /* If nothing has changed, this is a no-op */
1579         if ((fdq->d_fieldmask & FS_DQ_BSOFT) &&
1580             (fdq->d_blk_softlimit == be64_to_cpu(qd->qd_qb.qb_warn)))
1581                 fdq->d_fieldmask ^= FS_DQ_BSOFT;
1582         if ((fdq->d_fieldmask & FS_DQ_BHARD) &&
1583             (fdq->d_blk_hardlimit == be64_to_cpu(qd->qd_qb.qb_limit)))
1584                 fdq->d_fieldmask ^= FS_DQ_BHARD;
1585         if (fdq->d_fieldmask == 0)
1586                 goto out_i;
1587
1588         offset = qd2offset(qd);
1589         error = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota),
1590                                           &alloc_required);
1591         if (error)
1592                 goto out_i;
1593         if (alloc_required) {
1594                 al = gfs2_alloc_get(ip);
1595                 if (al == NULL)
1596                         goto out_i;
1597                 gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1598                                        &data_blocks, &ind_blocks);
1599                 blocks = al->al_requested = 1 + data_blocks + ind_blocks;
1600                 error = gfs2_inplace_reserve(ip);
1601                 if (error)
1602                         goto out_alloc;
1603         }
1604
1605         error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 1, 0);
1606         if (error)
1607                 goto out_release;
1608
1609         /* Apply changes */
1610         error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1611
1612         gfs2_trans_end(sdp);
1613 out_release:
1614         if (alloc_required) {
1615                 gfs2_inplace_release(ip);
1616 out_alloc:
1617                 gfs2_alloc_put(ip);
1618         }
1619 out_i:
1620         gfs2_glock_dq_uninit(&i_gh);
1621 out_q:
1622         gfs2_glock_dq_uninit(&q_gh);
1623 out_put:
1624         mutex_unlock(&ip->i_inode.i_mutex);
1625         qd_put(qd);
1626         return error;
1627 }
1628
1629 const struct quotactl_ops gfs2_quotactl_ops = {
1630         .quota_sync     = gfs2_quota_sync,
1631         .get_xstate     = gfs2_quota_get_xstate,
1632         .get_dqblk      = gfs2_get_dqblk,
1633         .set_dqblk      = gfs2_set_dqblk,
1634 };
1635