gfs2: nfs lock support for gfs2
[linux-2.6] / fs / gfs2 / quota.c
1 /*
2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
3  * Copyright (C) 2004-2006 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 to 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/lm_interface.h>
49
50 #include "gfs2.h"
51 #include "incore.h"
52 #include "bmap.h"
53 #include "glock.h"
54 #include "glops.h"
55 #include "log.h"
56 #include "meta_io.h"
57 #include "quota.h"
58 #include "rgrp.h"
59 #include "super.h"
60 #include "trans.h"
61 #include "inode.h"
62 #include "ops_file.h"
63 #include "ops_address.h"
64 #include "util.h"
65
66 #define QUOTA_USER 1
67 #define QUOTA_GROUP 0
68
69 static u64 qd2offset(struct gfs2_quota_data *qd)
70 {
71         u64 offset;
72
73         offset = 2 * (u64)qd->qd_id + !test_bit(QDF_USER, &qd->qd_flags);
74         offset *= sizeof(struct gfs2_quota);
75
76         return offset;
77 }
78
79 static int qd_alloc(struct gfs2_sbd *sdp, int user, u32 id,
80                     struct gfs2_quota_data **qdp)
81 {
82         struct gfs2_quota_data *qd;
83         int error;
84
85         qd = kzalloc(sizeof(struct gfs2_quota_data), GFP_KERNEL);
86         if (!qd)
87                 return -ENOMEM;
88
89         qd->qd_count = 1;
90         qd->qd_id = id;
91         if (user)
92                 set_bit(QDF_USER, &qd->qd_flags);
93         qd->qd_slot = -1;
94
95         error = gfs2_glock_get(sdp, 2 * (u64)id + !user,
96                               &gfs2_quota_glops, CREATE, &qd->qd_gl);
97         if (error)
98                 goto fail;
99
100         error = gfs2_lvb_hold(qd->qd_gl);
101         gfs2_glock_put(qd->qd_gl);
102         if (error)
103                 goto fail;
104
105         *qdp = qd;
106
107         return 0;
108
109 fail:
110         kfree(qd);
111         return error;
112 }
113
114 static int qd_get(struct gfs2_sbd *sdp, int user, u32 id, int create,
115                   struct gfs2_quota_data **qdp)
116 {
117         struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
118         int error, found;
119
120         *qdp = NULL;
121
122         for (;;) {
123                 found = 0;
124                 spin_lock(&sdp->sd_quota_spin);
125                 list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
126                         if (qd->qd_id == id &&
127                             !test_bit(QDF_USER, &qd->qd_flags) == !user) {
128                                 qd->qd_count++;
129                                 found = 1;
130                                 break;
131                         }
132                 }
133
134                 if (!found)
135                         qd = NULL;
136
137                 if (!qd && new_qd) {
138                         qd = new_qd;
139                         list_add(&qd->qd_list, &sdp->sd_quota_list);
140                         atomic_inc(&sdp->sd_quota_count);
141                         new_qd = NULL;
142                 }
143
144                 spin_unlock(&sdp->sd_quota_spin);
145
146                 if (qd || !create) {
147                         if (new_qd) {
148                                 gfs2_lvb_unhold(new_qd->qd_gl);
149                                 kfree(new_qd);
150                         }
151                         *qdp = qd;
152                         return 0;
153                 }
154
155                 error = qd_alloc(sdp, user, id, &new_qd);
156                 if (error)
157                         return error;
158         }
159 }
160
161 static void qd_hold(struct gfs2_quota_data *qd)
162 {
163         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
164
165         spin_lock(&sdp->sd_quota_spin);
166         gfs2_assert(sdp, qd->qd_count);
167         qd->qd_count++;
168         spin_unlock(&sdp->sd_quota_spin);
169 }
170
171 static void qd_put(struct gfs2_quota_data *qd)
172 {
173         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
174         spin_lock(&sdp->sd_quota_spin);
175         gfs2_assert(sdp, qd->qd_count);
176         if (!--qd->qd_count)
177                 qd->qd_last_touched = jiffies;
178         spin_unlock(&sdp->sd_quota_spin);
179 }
180
181 static int slot_get(struct gfs2_quota_data *qd)
182 {
183         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
184         unsigned int c, o = 0, b;
185         unsigned char byte = 0;
186
187         spin_lock(&sdp->sd_quota_spin);
188
189         if (qd->qd_slot_count++) {
190                 spin_unlock(&sdp->sd_quota_spin);
191                 return 0;
192         }
193
194         for (c = 0; c < sdp->sd_quota_chunks; c++)
195                 for (o = 0; o < PAGE_SIZE; o++) {
196                         byte = sdp->sd_quota_bitmap[c][o];
197                         if (byte != 0xFF)
198                                 goto found;
199                 }
200
201         goto fail;
202
203 found:
204         for (b = 0; b < 8; b++)
205                 if (!(byte & (1 << b)))
206                         break;
207         qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
208
209         if (qd->qd_slot >= sdp->sd_quota_slots)
210                 goto fail;
211
212         sdp->sd_quota_bitmap[c][o] |= 1 << b;
213
214         spin_unlock(&sdp->sd_quota_spin);
215
216         return 0;
217
218 fail:
219         qd->qd_slot_count--;
220         spin_unlock(&sdp->sd_quota_spin);
221         return -ENOSPC;
222 }
223
224 static void slot_hold(struct gfs2_quota_data *qd)
225 {
226         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
227
228         spin_lock(&sdp->sd_quota_spin);
229         gfs2_assert(sdp, qd->qd_slot_count);
230         qd->qd_slot_count++;
231         spin_unlock(&sdp->sd_quota_spin);
232 }
233
234 static void slot_put(struct gfs2_quota_data *qd)
235 {
236         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
237
238         spin_lock(&sdp->sd_quota_spin);
239         gfs2_assert(sdp, qd->qd_slot_count);
240         if (!--qd->qd_slot_count) {
241                 gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
242                 qd->qd_slot = -1;
243         }
244         spin_unlock(&sdp->sd_quota_spin);
245 }
246
247 static int bh_get(struct gfs2_quota_data *qd)
248 {
249         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
250         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
251         unsigned int block, offset;
252         struct buffer_head *bh;
253         int error;
254         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
255
256         mutex_lock(&sdp->sd_quota_mutex);
257
258         if (qd->qd_bh_count++) {
259                 mutex_unlock(&sdp->sd_quota_mutex);
260                 return 0;
261         }
262
263         block = qd->qd_slot / sdp->sd_qc_per_block;
264         offset = qd->qd_slot % sdp->sd_qc_per_block;;
265
266         bh_map.b_size = 1 << ip->i_inode.i_blkbits;
267         error = gfs2_block_map(&ip->i_inode, block, 0, &bh_map);
268         if (error)
269                 goto fail;
270         error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
271         if (error)
272                 goto fail;
273         error = -EIO;
274         if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
275                 goto fail_brelse;
276
277         qd->qd_bh = bh;
278         qd->qd_bh_qc = (struct gfs2_quota_change *)
279                 (bh->b_data + sizeof(struct gfs2_meta_header) +
280                  offset * sizeof(struct gfs2_quota_change));
281
282         mutex_unlock(&sdp->sd_quota_mutex);
283
284         return 0;
285
286 fail_brelse:
287         brelse(bh);
288 fail:
289         qd->qd_bh_count--;
290         mutex_unlock(&sdp->sd_quota_mutex);
291         return error;
292 }
293
294 static void bh_put(struct gfs2_quota_data *qd)
295 {
296         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
297
298         mutex_lock(&sdp->sd_quota_mutex);
299         gfs2_assert(sdp, qd->qd_bh_count);
300         if (!--qd->qd_bh_count) {
301                 brelse(qd->qd_bh);
302                 qd->qd_bh = NULL;
303                 qd->qd_bh_qc = NULL;
304         }
305         mutex_unlock(&sdp->sd_quota_mutex);
306 }
307
308 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
309 {
310         struct gfs2_quota_data *qd = NULL;
311         int error;
312         int found = 0;
313
314         *qdp = NULL;
315
316         if (sdp->sd_vfs->s_flags & MS_RDONLY)
317                 return 0;
318
319         spin_lock(&sdp->sd_quota_spin);
320
321         list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
322                 if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
323                     !test_bit(QDF_CHANGE, &qd->qd_flags) ||
324                     qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
325                         continue;
326
327                 list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
328
329                 set_bit(QDF_LOCKED, &qd->qd_flags);
330                 gfs2_assert_warn(sdp, qd->qd_count);
331                 qd->qd_count++;
332                 qd->qd_change_sync = qd->qd_change;
333                 gfs2_assert_warn(sdp, qd->qd_slot_count);
334                 qd->qd_slot_count++;
335                 found = 1;
336
337                 break;
338         }
339
340         if (!found)
341                 qd = NULL;
342
343         spin_unlock(&sdp->sd_quota_spin);
344
345         if (qd) {
346                 gfs2_assert_warn(sdp, qd->qd_change_sync);
347                 error = bh_get(qd);
348                 if (error) {
349                         clear_bit(QDF_LOCKED, &qd->qd_flags);
350                         slot_put(qd);
351                         qd_put(qd);
352                         return error;
353                 }
354         }
355
356         *qdp = qd;
357
358         return 0;
359 }
360
361 static int qd_trylock(struct gfs2_quota_data *qd)
362 {
363         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
364
365         if (sdp->sd_vfs->s_flags & MS_RDONLY)
366                 return 0;
367
368         spin_lock(&sdp->sd_quota_spin);
369
370         if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
371             !test_bit(QDF_CHANGE, &qd->qd_flags)) {
372                 spin_unlock(&sdp->sd_quota_spin);
373                 return 0;
374         }
375
376         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
377
378         set_bit(QDF_LOCKED, &qd->qd_flags);
379         gfs2_assert_warn(sdp, qd->qd_count);
380         qd->qd_count++;
381         qd->qd_change_sync = qd->qd_change;
382         gfs2_assert_warn(sdp, qd->qd_slot_count);
383         qd->qd_slot_count++;
384
385         spin_unlock(&sdp->sd_quota_spin);
386
387         gfs2_assert_warn(sdp, qd->qd_change_sync);
388         if (bh_get(qd)) {
389                 clear_bit(QDF_LOCKED, &qd->qd_flags);
390                 slot_put(qd);
391                 qd_put(qd);
392                 return 0;
393         }
394
395         return 1;
396 }
397
398 static void qd_unlock(struct gfs2_quota_data *qd)
399 {
400         gfs2_assert_warn(qd->qd_gl->gl_sbd,
401                          test_bit(QDF_LOCKED, &qd->qd_flags));
402         clear_bit(QDF_LOCKED, &qd->qd_flags);
403         bh_put(qd);
404         slot_put(qd);
405         qd_put(qd);
406 }
407
408 static int qdsb_get(struct gfs2_sbd *sdp, int user, u32 id, int create,
409                     struct gfs2_quota_data **qdp)
410 {
411         int error;
412
413         error = qd_get(sdp, user, id, create, qdp);
414         if (error)
415                 return error;
416
417         error = slot_get(*qdp);
418         if (error)
419                 goto fail;
420
421         error = bh_get(*qdp);
422         if (error)
423                 goto fail_slot;
424
425         return 0;
426
427 fail_slot:
428         slot_put(*qdp);
429 fail:
430         qd_put(*qdp);
431         return error;
432 }
433
434 static void qdsb_put(struct gfs2_quota_data *qd)
435 {
436         bh_put(qd);
437         slot_put(qd);
438         qd_put(qd);
439 }
440
441 int gfs2_quota_hold(struct gfs2_inode *ip, u32 uid, u32 gid)
442 {
443         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
444         struct gfs2_alloc *al = &ip->i_alloc;
445         struct gfs2_quota_data **qd = al->al_qd;
446         int error;
447
448         if (gfs2_assert_warn(sdp, !al->al_qd_num) ||
449             gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
450                 return -EIO;
451
452         if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
453                 return 0;
454
455         error = qdsb_get(sdp, QUOTA_USER, ip->i_inode.i_uid, CREATE, qd);
456         if (error)
457                 goto out;
458         al->al_qd_num++;
459         qd++;
460
461         error = qdsb_get(sdp, QUOTA_GROUP, ip->i_inode.i_gid, CREATE, qd);
462         if (error)
463                 goto out;
464         al->al_qd_num++;
465         qd++;
466
467         if (uid != NO_QUOTA_CHANGE && uid != ip->i_inode.i_uid) {
468                 error = qdsb_get(sdp, QUOTA_USER, uid, CREATE, qd);
469                 if (error)
470                         goto out;
471                 al->al_qd_num++;
472                 qd++;
473         }
474
475         if (gid != NO_QUOTA_CHANGE && gid != ip->i_inode.i_gid) {
476                 error = qdsb_get(sdp, QUOTA_GROUP, gid, CREATE, qd);
477                 if (error)
478                         goto out;
479                 al->al_qd_num++;
480                 qd++;
481         }
482
483 out:
484         if (error)
485                 gfs2_quota_unhold(ip);
486         return error;
487 }
488
489 void gfs2_quota_unhold(struct gfs2_inode *ip)
490 {
491         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
492         struct gfs2_alloc *al = &ip->i_alloc;
493         unsigned int x;
494
495         gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
496
497         for (x = 0; x < al->al_qd_num; x++) {
498                 qdsb_put(al->al_qd[x]);
499                 al->al_qd[x] = NULL;
500         }
501         al->al_qd_num = 0;
502 }
503
504 static int sort_qd(const void *a, const void *b)
505 {
506         const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
507         const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
508
509         if (!test_bit(QDF_USER, &qd_a->qd_flags) !=
510             !test_bit(QDF_USER, &qd_b->qd_flags)) {
511                 if (test_bit(QDF_USER, &qd_a->qd_flags))
512                         return -1;
513                 else
514                         return 1;
515         }
516         if (qd_a->qd_id < qd_b->qd_id)
517                 return -1;
518         if (qd_a->qd_id > qd_b->qd_id)
519                 return 1;
520
521         return 0;
522 }
523
524 static void do_qc(struct gfs2_quota_data *qd, s64 change)
525 {
526         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
527         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
528         struct gfs2_quota_change *qc = qd->qd_bh_qc;
529         s64 x;
530
531         mutex_lock(&sdp->sd_quota_mutex);
532         gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
533
534         if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
535                 qc->qc_change = 0;
536                 qc->qc_flags = 0;
537                 if (test_bit(QDF_USER, &qd->qd_flags))
538                         qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
539                 qc->qc_id = cpu_to_be32(qd->qd_id);
540         }
541
542         x = be64_to_cpu(qc->qc_change) + change;
543         qc->qc_change = cpu_to_be64(x);
544
545         spin_lock(&sdp->sd_quota_spin);
546         qd->qd_change = x;
547         spin_unlock(&sdp->sd_quota_spin);
548
549         if (!x) {
550                 gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
551                 clear_bit(QDF_CHANGE, &qd->qd_flags);
552                 qc->qc_flags = 0;
553                 qc->qc_id = 0;
554                 slot_put(qd);
555                 qd_put(qd);
556         } else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
557                 qd_hold(qd);
558                 slot_hold(qd);
559         }
560
561         mutex_unlock(&sdp->sd_quota_mutex);
562 }
563
564 /**
565  * gfs2_adjust_quota
566  *
567  * This function was mostly borrowed from gfs2_block_truncate_page which was
568  * in turn mostly borrowed from ext3
569  */
570 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
571                              s64 change, struct gfs2_quota_data *qd)
572 {
573         struct inode *inode = &ip->i_inode;
574         struct address_space *mapping = inode->i_mapping;
575         unsigned long index = loc >> PAGE_CACHE_SHIFT;
576         unsigned offset = loc & (PAGE_CACHE_SHIFT - 1);
577         unsigned blocksize, iblock, pos;
578         struct buffer_head *bh;
579         struct page *page;
580         void *kaddr;
581         __be64 *ptr;
582         s64 value;
583         int err = -EIO;
584
585         page = grab_cache_page(mapping, index);
586         if (!page)
587                 return -ENOMEM;
588
589         blocksize = inode->i_sb->s_blocksize;
590         iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
591
592         if (!page_has_buffers(page))
593                 create_empty_buffers(page, blocksize, 0);
594
595         bh = page_buffers(page);
596         pos = blocksize;
597         while (offset >= pos) {
598                 bh = bh->b_this_page;
599                 iblock++;
600                 pos += blocksize;
601         }
602
603         if (!buffer_mapped(bh)) {
604                 gfs2_get_block(inode, iblock, bh, 1);
605                 if (!buffer_mapped(bh))
606                         goto unlock;
607         }
608
609         if (PageUptodate(page))
610                 set_buffer_uptodate(bh);
611
612         if (!buffer_uptodate(bh)) {
613                 ll_rw_block(READ_META, 1, &bh);
614                 wait_on_buffer(bh);
615                 if (!buffer_uptodate(bh))
616                         goto unlock;
617         }
618
619         gfs2_trans_add_bh(ip->i_gl, bh, 0);
620
621         kaddr = kmap_atomic(page, KM_USER0);
622         ptr = kaddr + offset;
623         value = (s64)be64_to_cpu(*ptr) + change;
624         *ptr = cpu_to_be64(value);
625         flush_dcache_page(page);
626         kunmap_atomic(kaddr, KM_USER0);
627         err = 0;
628         qd->qd_qb.qb_magic = cpu_to_be32(GFS2_MAGIC);
629         qd->qd_qb.qb_value = cpu_to_be64(value);
630 unlock:
631         unlock_page(page);
632         page_cache_release(page);
633         return err;
634 }
635
636 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
637 {
638         struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
639         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
640         unsigned int data_blocks, ind_blocks;
641         struct gfs2_holder *ghs, i_gh;
642         unsigned int qx, x;
643         struct gfs2_quota_data *qd;
644         loff_t offset;
645         unsigned int nalloc = 0;
646         struct gfs2_alloc *al = NULL;
647         int error;
648
649         gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
650                               &data_blocks, &ind_blocks);
651
652         ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_KERNEL);
653         if (!ghs)
654                 return -ENOMEM;
655
656         sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
657         for (qx = 0; qx < num_qd; qx++) {
658                 error = gfs2_glock_nq_init(qda[qx]->qd_gl,
659                                            LM_ST_EXCLUSIVE,
660                                            GL_NOCACHE, &ghs[qx]);
661                 if (error)
662                         goto out;
663         }
664
665         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
666         if (error)
667                 goto out;
668
669         for (x = 0; x < num_qd; x++) {
670                 int alloc_required;
671
672                 offset = qd2offset(qda[x]);
673                 error = gfs2_write_alloc_required(ip, offset,
674                                                   sizeof(struct gfs2_quota),
675                                                   &alloc_required);
676                 if (error)
677                         goto out_gunlock;
678                 if (alloc_required)
679                         nalloc++;
680         }
681
682         if (nalloc) {
683                 al = gfs2_alloc_get(ip);
684
685                 al->al_requested = nalloc * (data_blocks + ind_blocks);
686
687                 error = gfs2_inplace_reserve(ip);
688                 if (error)
689                         goto out_alloc;
690
691                 error = gfs2_trans_begin(sdp,
692                                          al->al_rgd->rd_ri.ri_length +
693                                          num_qd * data_blocks +
694                                          nalloc * ind_blocks +
695                                          RES_DINODE + num_qd +
696                                          RES_STATFS, 0);
697                 if (error)
698                         goto out_ipres;
699         } else {
700                 error = gfs2_trans_begin(sdp,
701                                          num_qd * data_blocks +
702                                          RES_DINODE + num_qd, 0);
703                 if (error)
704                         goto out_gunlock;
705         }
706
707         for (x = 0; x < num_qd; x++) {
708                 qd = qda[x];
709                 offset = qd2offset(qd);
710                 error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync,
711                                           (struct gfs2_quota_data *)
712                                           qd->qd_gl->gl_lvb);
713                 if (error)
714                         goto out_end_trans;
715
716                 do_qc(qd, -qd->qd_change_sync);
717         }
718
719         error = 0;
720
721 out_end_trans:
722         gfs2_trans_end(sdp);
723 out_ipres:
724         if (nalloc)
725                 gfs2_inplace_release(ip);
726 out_alloc:
727         if (nalloc)
728                 gfs2_alloc_put(ip);
729 out_gunlock:
730         gfs2_glock_dq_uninit(&i_gh);
731 out:
732         while (qx--)
733                 gfs2_glock_dq_uninit(&ghs[qx]);
734         kfree(ghs);
735         gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
736         return error;
737 }
738
739 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
740                     struct gfs2_holder *q_gh)
741 {
742         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
743         struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
744         struct gfs2_holder i_gh;
745         struct gfs2_quota_host q;
746         char buf[sizeof(struct gfs2_quota)];
747         struct file_ra_state ra_state;
748         int error;
749         struct gfs2_quota_lvb *qlvb;
750
751         file_ra_state_init(&ra_state, sdp->sd_quota_inode->i_mapping);
752 restart:
753         error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
754         if (error)
755                 return error;
756
757         qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
758
759         if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
760                 loff_t pos;
761                 gfs2_glock_dq_uninit(q_gh);
762                 error = gfs2_glock_nq_init(qd->qd_gl,
763                                           LM_ST_EXCLUSIVE, GL_NOCACHE,
764                                           q_gh);
765                 if (error)
766                         return error;
767
768                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
769                 if (error)
770                         goto fail;
771
772                 memset(buf, 0, sizeof(struct gfs2_quota));
773                 pos = qd2offset(qd);
774                 error = gfs2_internal_read(ip, &ra_state, buf,
775                                            &pos, sizeof(struct gfs2_quota));
776                 if (error < 0)
777                         goto fail_gunlock;
778
779                 gfs2_glock_dq_uninit(&i_gh);
780
781
782                 gfs2_quota_in(&q, buf);
783                 qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
784                 qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
785                 qlvb->__pad = 0;
786                 qlvb->qb_limit = cpu_to_be64(q.qu_limit);
787                 qlvb->qb_warn = cpu_to_be64(q.qu_warn);
788                 qlvb->qb_value = cpu_to_be64(q.qu_value);
789                 qd->qd_qb = *qlvb;
790
791                 if (gfs2_glock_is_blocking(qd->qd_gl)) {
792                         gfs2_glock_dq_uninit(q_gh);
793                         force_refresh = 0;
794                         goto restart;
795                 }
796         }
797
798         return 0;
799
800 fail_gunlock:
801         gfs2_glock_dq_uninit(&i_gh);
802 fail:
803         gfs2_glock_dq_uninit(q_gh);
804         return error;
805 }
806
807 int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
808 {
809         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
810         struct gfs2_alloc *al = &ip->i_alloc;
811         unsigned int x;
812         int error = 0;
813
814         gfs2_quota_hold(ip, uid, gid);
815
816         if (capable(CAP_SYS_RESOURCE) ||
817             sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
818                 return 0;
819
820         sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
821              sort_qd, NULL);
822
823         for (x = 0; x < al->al_qd_num; x++) {
824                 error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
825                 if (error)
826                         break;
827         }
828
829         if (!error)
830                 set_bit(GIF_QD_LOCKED, &ip->i_flags);
831         else {
832                 while (x--)
833                         gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
834                 gfs2_quota_unhold(ip);
835         }
836
837         return error;
838 }
839
840 static int need_sync(struct gfs2_quota_data *qd)
841 {
842         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
843         struct gfs2_tune *gt = &sdp->sd_tune;
844         s64 value;
845         unsigned int num, den;
846         int do_sync = 1;
847
848         if (!qd->qd_qb.qb_limit)
849                 return 0;
850
851         spin_lock(&sdp->sd_quota_spin);
852         value = qd->qd_change;
853         spin_unlock(&sdp->sd_quota_spin);
854
855         spin_lock(&gt->gt_spin);
856         num = gt->gt_quota_scale_num;
857         den = gt->gt_quota_scale_den;
858         spin_unlock(&gt->gt_spin);
859
860         if (value < 0)
861                 do_sync = 0;
862         else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
863                  (s64)be64_to_cpu(qd->qd_qb.qb_limit))
864                 do_sync = 0;
865         else {
866                 value *= gfs2_jindex_size(sdp) * num;
867                 do_div(value, den);
868                 value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
869                 if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
870                         do_sync = 0;
871         }
872
873         return do_sync;
874 }
875
876 void gfs2_quota_unlock(struct gfs2_inode *ip)
877 {
878         struct gfs2_alloc *al = &ip->i_alloc;
879         struct gfs2_quota_data *qda[4];
880         unsigned int count = 0;
881         unsigned int x;
882
883         if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
884                 goto out;
885
886         for (x = 0; x < al->al_qd_num; x++) {
887                 struct gfs2_quota_data *qd;
888                 int sync;
889
890                 qd = al->al_qd[x];
891                 sync = need_sync(qd);
892
893                 gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
894
895                 if (sync && qd_trylock(qd))
896                         qda[count++] = qd;
897         }
898
899         if (count) {
900                 do_sync(count, qda);
901                 for (x = 0; x < count; x++)
902                         qd_unlock(qda[x]);
903         }
904
905 out:
906         gfs2_quota_unhold(ip);
907 }
908
909 #define MAX_LINE 256
910
911 static int print_message(struct gfs2_quota_data *qd, char *type)
912 {
913         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
914
915         printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\r\n",
916                sdp->sd_fsname, type,
917                (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
918                qd->qd_id);
919
920         return 0;
921 }
922
923 int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
924 {
925         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
926         struct gfs2_alloc *al = &ip->i_alloc;
927         struct gfs2_quota_data *qd;
928         s64 value;
929         unsigned int x;
930         int error = 0;
931
932         if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
933                 return 0;
934
935         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
936                 return 0;
937
938         for (x = 0; x < al->al_qd_num; x++) {
939                 qd = al->al_qd[x];
940
941                 if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
942                       (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
943                         continue;
944
945                 value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
946                 spin_lock(&sdp->sd_quota_spin);
947                 value += qd->qd_change;
948                 spin_unlock(&sdp->sd_quota_spin);
949
950                 if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
951                         print_message(qd, "exceeded");
952                         error = -EDQUOT;
953                         break;
954                 } else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
955                            (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
956                            time_after_eq(jiffies, qd->qd_last_warn +
957                                          gfs2_tune_get(sdp,
958                                                 gt_quota_warn_period) * HZ)) {
959                         error = print_message(qd, "warning");
960                         qd->qd_last_warn = jiffies;
961                 }
962         }
963
964         return error;
965 }
966
967 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
968                        u32 uid, u32 gid)
969 {
970         struct gfs2_alloc *al = &ip->i_alloc;
971         struct gfs2_quota_data *qd;
972         unsigned int x;
973         unsigned int found = 0;
974
975         if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
976                 return;
977         if (ip->i_di.di_flags & GFS2_DIF_SYSTEM)
978                 return;
979
980         for (x = 0; x < al->al_qd_num; x++) {
981                 qd = al->al_qd[x];
982
983                 if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
984                     (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
985                         do_qc(qd, change);
986                         found++;
987                 }
988         }
989 }
990
991 int gfs2_quota_sync(struct gfs2_sbd *sdp)
992 {
993         struct gfs2_quota_data **qda;
994         unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
995         unsigned int num_qd;
996         unsigned int x;
997         int error = 0;
998
999         sdp->sd_quota_sync_gen++;
1000
1001         qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1002         if (!qda)
1003                 return -ENOMEM;
1004
1005         do {
1006                 num_qd = 0;
1007
1008                 for (;;) {
1009                         error = qd_fish(sdp, qda + num_qd);
1010                         if (error || !qda[num_qd])
1011                                 break;
1012                         if (++num_qd == max_qd)
1013                                 break;
1014                 }
1015
1016                 if (num_qd) {
1017                         if (!error)
1018                                 error = do_sync(num_qd, qda);
1019                         if (!error)
1020                                 for (x = 0; x < num_qd; x++)
1021                                         qda[x]->qd_sync_gen =
1022                                                 sdp->sd_quota_sync_gen;
1023
1024                         for (x = 0; x < num_qd; x++)
1025                                 qd_unlock(qda[x]);
1026                 }
1027         } while (!error && num_qd == max_qd);
1028
1029         kfree(qda);
1030
1031         return error;
1032 }
1033
1034 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
1035 {
1036         struct gfs2_quota_data *qd;
1037         struct gfs2_holder q_gh;
1038         int error;
1039
1040         error = qd_get(sdp, user, id, CREATE, &qd);
1041         if (error)
1042                 return error;
1043
1044         error = do_glock(qd, FORCE, &q_gh);
1045         if (!error)
1046                 gfs2_glock_dq_uninit(&q_gh);
1047
1048         qd_put(qd);
1049
1050         return error;
1051 }
1052
1053 int gfs2_quota_init(struct gfs2_sbd *sdp)
1054 {
1055         struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1056         unsigned int blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
1057         unsigned int x, slot = 0;
1058         unsigned int found = 0;
1059         u64 dblock;
1060         u32 extlen = 0;
1061         int error;
1062
1063         if (!ip->i_di.di_size || ip->i_di.di_size > (64 << 20) ||
1064             ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1)) {
1065                 gfs2_consist_inode(ip);
1066                 return -EIO;
1067         }
1068         sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1069         sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1070
1071         error = -ENOMEM;
1072
1073         sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1074                                        sizeof(unsigned char *), GFP_KERNEL);
1075         if (!sdp->sd_quota_bitmap)
1076                 return error;
1077
1078         for (x = 0; x < sdp->sd_quota_chunks; x++) {
1079                 sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_KERNEL);
1080                 if (!sdp->sd_quota_bitmap[x])
1081                         goto fail;
1082         }
1083
1084         for (x = 0; x < blocks; x++) {
1085                 struct buffer_head *bh;
1086                 unsigned int y;
1087
1088                 if (!extlen) {
1089                         int new = 0;
1090                         error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1091                         if (error)
1092                                 goto fail;
1093                 }
1094                 error = -EIO;
1095                 bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1096                 if (!bh)
1097                         goto fail;
1098                 if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1099                         brelse(bh);
1100                         goto fail;
1101                 }
1102
1103                 for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1104                      y++, slot++) {
1105                         struct gfs2_quota_change_host qc;
1106                         struct gfs2_quota_data *qd;
1107
1108                         gfs2_quota_change_in(&qc, bh->b_data +
1109                                           sizeof(struct gfs2_meta_header) +
1110                                           y * sizeof(struct gfs2_quota_change));
1111                         if (!qc.qc_change)
1112                                 continue;
1113
1114                         error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1115                                          qc.qc_id, &qd);
1116                         if (error) {
1117                                 brelse(bh);
1118                                 goto fail;
1119                         }
1120
1121                         set_bit(QDF_CHANGE, &qd->qd_flags);
1122                         qd->qd_change = qc.qc_change;
1123                         qd->qd_slot = slot;
1124                         qd->qd_slot_count = 1;
1125                         qd->qd_last_touched = jiffies;
1126
1127                         spin_lock(&sdp->sd_quota_spin);
1128                         gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1129                         list_add(&qd->qd_list, &sdp->sd_quota_list);
1130                         atomic_inc(&sdp->sd_quota_count);
1131                         spin_unlock(&sdp->sd_quota_spin);
1132
1133                         found++;
1134                 }
1135
1136                 brelse(bh);
1137                 dblock++;
1138                 extlen--;
1139         }
1140
1141         if (found)
1142                 fs_info(sdp, "found %u quota changes\n", found);
1143
1144         return 0;
1145
1146 fail:
1147         gfs2_quota_cleanup(sdp);
1148         return error;
1149 }
1150
1151 void gfs2_quota_scan(struct gfs2_sbd *sdp)
1152 {
1153         struct gfs2_quota_data *qd, *safe;
1154         LIST_HEAD(dead);
1155
1156         spin_lock(&sdp->sd_quota_spin);
1157         list_for_each_entry_safe(qd, safe, &sdp->sd_quota_list, qd_list) {
1158                 if (!qd->qd_count &&
1159                     time_after_eq(jiffies, qd->qd_last_touched +
1160                                 gfs2_tune_get(sdp, gt_quota_cache_secs) * HZ)) {
1161                         list_move(&qd->qd_list, &dead);
1162                         gfs2_assert_warn(sdp,
1163                                          atomic_read(&sdp->sd_quota_count) > 0);
1164                         atomic_dec(&sdp->sd_quota_count);
1165                 }
1166         }
1167         spin_unlock(&sdp->sd_quota_spin);
1168
1169         while (!list_empty(&dead)) {
1170                 qd = list_entry(dead.next, struct gfs2_quota_data, qd_list);
1171                 list_del(&qd->qd_list);
1172
1173                 gfs2_assert_warn(sdp, !qd->qd_change);
1174                 gfs2_assert_warn(sdp, !qd->qd_slot_count);
1175                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1176
1177                 gfs2_lvb_unhold(qd->qd_gl);
1178                 kfree(qd);
1179         }
1180 }
1181
1182 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1183 {
1184         struct list_head *head = &sdp->sd_quota_list;
1185         struct gfs2_quota_data *qd;
1186         unsigned int x;
1187
1188         spin_lock(&sdp->sd_quota_spin);
1189         while (!list_empty(head)) {
1190                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1191
1192                 if (qd->qd_count > 1 ||
1193                     (qd->qd_count && !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1194                         list_move(&qd->qd_list, head);
1195                         spin_unlock(&sdp->sd_quota_spin);
1196                         schedule();
1197                         spin_lock(&sdp->sd_quota_spin);
1198                         continue;
1199                 }
1200
1201                 list_del(&qd->qd_list);
1202                 atomic_dec(&sdp->sd_quota_count);
1203                 spin_unlock(&sdp->sd_quota_spin);
1204
1205                 if (!qd->qd_count) {
1206                         gfs2_assert_warn(sdp, !qd->qd_change);
1207                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
1208                 } else
1209                         gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1210                 gfs2_assert_warn(sdp, !qd->qd_bh_count);
1211
1212                 gfs2_lvb_unhold(qd->qd_gl);
1213                 kfree(qd);
1214
1215                 spin_lock(&sdp->sd_quota_spin);
1216         }
1217         spin_unlock(&sdp->sd_quota_spin);
1218
1219         gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1220
1221         if (sdp->sd_quota_bitmap) {
1222                 for (x = 0; x < sdp->sd_quota_chunks; x++)
1223                         kfree(sdp->sd_quota_bitmap[x]);
1224                 kfree(sdp->sd_quota_bitmap);
1225         }
1226 }
1227