xref: /openbmc/linux/fs/gfs2/quota.c (revision 81d67439)
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/mm.h>
42 #include <linux/spinlock.h>
43 #include <linux/completion.h>
44 #include <linux/buffer_head.h>
45 #include <linux/sort.h>
46 #include <linux/fs.h>
47 #include <linux/bio.h>
48 #include <linux/gfs2_ondisk.h>
49 #include <linux/kthread.h>
50 #include <linux/freezer.h>
51 #include <linux/quota.h>
52 #include <linux/dqblk_xfs.h>
53 
54 #include "gfs2.h"
55 #include "incore.h"
56 #include "bmap.h"
57 #include "glock.h"
58 #include "glops.h"
59 #include "log.h"
60 #include "meta_io.h"
61 #include "quota.h"
62 #include "rgrp.h"
63 #include "super.h"
64 #include "trans.h"
65 #include "inode.h"
66 #include "util.h"
67 
68 #define QUOTA_USER 1
69 #define QUOTA_GROUP 0
70 
71 struct gfs2_quota_change_host {
72 	u64 qc_change;
73 	u32 qc_flags; /* GFS2_QCF_... */
74 	u32 qc_id;
75 };
76 
77 static LIST_HEAD(qd_lru_list);
78 static atomic_t qd_lru_count = ATOMIC_INIT(0);
79 static DEFINE_SPINLOCK(qd_lru_lock);
80 
81 int gfs2_shrink_qd_memory(struct shrinker *shrink, struct shrink_control *sc)
82 {
83 	struct gfs2_quota_data *qd;
84 	struct gfs2_sbd *sdp;
85 	int nr_to_scan = sc->nr_to_scan;
86 
87 	if (nr_to_scan == 0)
88 		goto out;
89 
90 	if (!(sc->gfp_mask & __GFP_FS))
91 		return -1;
92 
93 	spin_lock(&qd_lru_lock);
94 	while (nr_to_scan && !list_empty(&qd_lru_list)) {
95 		qd = list_entry(qd_lru_list.next,
96 				struct gfs2_quota_data, qd_reclaim);
97 		sdp = qd->qd_gl->gl_sbd;
98 
99 		/* Free from the filesystem-specific list */
100 		list_del(&qd->qd_list);
101 
102 		gfs2_assert_warn(sdp, !qd->qd_change);
103 		gfs2_assert_warn(sdp, !qd->qd_slot_count);
104 		gfs2_assert_warn(sdp, !qd->qd_bh_count);
105 
106 		gfs2_glock_put(qd->qd_gl);
107 		atomic_dec(&sdp->sd_quota_count);
108 
109 		/* Delete it from the common reclaim list */
110 		list_del_init(&qd->qd_reclaim);
111 		atomic_dec(&qd_lru_count);
112 		spin_unlock(&qd_lru_lock);
113 		kmem_cache_free(gfs2_quotad_cachep, qd);
114 		spin_lock(&qd_lru_lock);
115 		nr_to_scan--;
116 	}
117 	spin_unlock(&qd_lru_lock);
118 
119 out:
120 	return (atomic_read(&qd_lru_count) * sysctl_vfs_cache_pressure) / 100;
121 }
122 
123 static u64 qd2offset(struct gfs2_quota_data *qd)
124 {
125 	u64 offset;
126 
127 	offset = 2 * (u64)qd->qd_id + !test_bit(QDF_USER, &qd->qd_flags);
128 	offset *= sizeof(struct gfs2_quota);
129 
130 	return offset;
131 }
132 
133 static int qd_alloc(struct gfs2_sbd *sdp, int user, u32 id,
134 		    struct gfs2_quota_data **qdp)
135 {
136 	struct gfs2_quota_data *qd;
137 	int error;
138 
139 	qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
140 	if (!qd)
141 		return -ENOMEM;
142 
143 	atomic_set(&qd->qd_count, 1);
144 	qd->qd_id = id;
145 	if (user)
146 		set_bit(QDF_USER, &qd->qd_flags);
147 	qd->qd_slot = -1;
148 	INIT_LIST_HEAD(&qd->qd_reclaim);
149 
150 	error = gfs2_glock_get(sdp, 2 * (u64)id + !user,
151 			      &gfs2_quota_glops, CREATE, &qd->qd_gl);
152 	if (error)
153 		goto fail;
154 
155 	*qdp = qd;
156 
157 	return 0;
158 
159 fail:
160 	kmem_cache_free(gfs2_quotad_cachep, qd);
161 	return error;
162 }
163 
164 static int qd_get(struct gfs2_sbd *sdp, int user, u32 id,
165 		  struct gfs2_quota_data **qdp)
166 {
167 	struct gfs2_quota_data *qd = NULL, *new_qd = NULL;
168 	int error, found;
169 
170 	*qdp = NULL;
171 
172 	for (;;) {
173 		found = 0;
174 		spin_lock(&qd_lru_lock);
175 		list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
176 			if (qd->qd_id == id &&
177 			    !test_bit(QDF_USER, &qd->qd_flags) == !user) {
178 				if (!atomic_read(&qd->qd_count) &&
179 				    !list_empty(&qd->qd_reclaim)) {
180 					/* Remove it from reclaim list */
181 					list_del_init(&qd->qd_reclaim);
182 					atomic_dec(&qd_lru_count);
183 				}
184 				atomic_inc(&qd->qd_count);
185 				found = 1;
186 				break;
187 			}
188 		}
189 
190 		if (!found)
191 			qd = NULL;
192 
193 		if (!qd && new_qd) {
194 			qd = new_qd;
195 			list_add(&qd->qd_list, &sdp->sd_quota_list);
196 			atomic_inc(&sdp->sd_quota_count);
197 			new_qd = NULL;
198 		}
199 
200 		spin_unlock(&qd_lru_lock);
201 
202 		if (qd) {
203 			if (new_qd) {
204 				gfs2_glock_put(new_qd->qd_gl);
205 				kmem_cache_free(gfs2_quotad_cachep, new_qd);
206 			}
207 			*qdp = qd;
208 			return 0;
209 		}
210 
211 		error = qd_alloc(sdp, user, id, &new_qd);
212 		if (error)
213 			return error;
214 	}
215 }
216 
217 static void qd_hold(struct gfs2_quota_data *qd)
218 {
219 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
220 	gfs2_assert(sdp, atomic_read(&qd->qd_count));
221 	atomic_inc(&qd->qd_count);
222 }
223 
224 static void qd_put(struct gfs2_quota_data *qd)
225 {
226 	if (atomic_dec_and_lock(&qd->qd_count, &qd_lru_lock)) {
227 		/* Add to the reclaim list */
228 		list_add_tail(&qd->qd_reclaim, &qd_lru_list);
229 		atomic_inc(&qd_lru_count);
230 		spin_unlock(&qd_lru_lock);
231 	}
232 }
233 
234 static int slot_get(struct gfs2_quota_data *qd)
235 {
236 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
237 	unsigned int c, o = 0, b;
238 	unsigned char byte = 0;
239 
240 	spin_lock(&qd_lru_lock);
241 
242 	if (qd->qd_slot_count++) {
243 		spin_unlock(&qd_lru_lock);
244 		return 0;
245 	}
246 
247 	for (c = 0; c < sdp->sd_quota_chunks; c++)
248 		for (o = 0; o < PAGE_SIZE; o++) {
249 			byte = sdp->sd_quota_bitmap[c][o];
250 			if (byte != 0xFF)
251 				goto found;
252 		}
253 
254 	goto fail;
255 
256 found:
257 	for (b = 0; b < 8; b++)
258 		if (!(byte & (1 << b)))
259 			break;
260 	qd->qd_slot = c * (8 * PAGE_SIZE) + o * 8 + b;
261 
262 	if (qd->qd_slot >= sdp->sd_quota_slots)
263 		goto fail;
264 
265 	sdp->sd_quota_bitmap[c][o] |= 1 << b;
266 
267 	spin_unlock(&qd_lru_lock);
268 
269 	return 0;
270 
271 fail:
272 	qd->qd_slot_count--;
273 	spin_unlock(&qd_lru_lock);
274 	return -ENOSPC;
275 }
276 
277 static void slot_hold(struct gfs2_quota_data *qd)
278 {
279 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
280 
281 	spin_lock(&qd_lru_lock);
282 	gfs2_assert(sdp, qd->qd_slot_count);
283 	qd->qd_slot_count++;
284 	spin_unlock(&qd_lru_lock);
285 }
286 
287 static void slot_put(struct gfs2_quota_data *qd)
288 {
289 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
290 
291 	spin_lock(&qd_lru_lock);
292 	gfs2_assert(sdp, qd->qd_slot_count);
293 	if (!--qd->qd_slot_count) {
294 		gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, qd->qd_slot, 0);
295 		qd->qd_slot = -1;
296 	}
297 	spin_unlock(&qd_lru_lock);
298 }
299 
300 static int bh_get(struct gfs2_quota_data *qd)
301 {
302 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
303 	struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
304 	unsigned int block, offset;
305 	struct buffer_head *bh;
306 	int error;
307 	struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
308 
309 	mutex_lock(&sdp->sd_quota_mutex);
310 
311 	if (qd->qd_bh_count++) {
312 		mutex_unlock(&sdp->sd_quota_mutex);
313 		return 0;
314 	}
315 
316 	block = qd->qd_slot / sdp->sd_qc_per_block;
317 	offset = qd->qd_slot % sdp->sd_qc_per_block;
318 
319 	bh_map.b_size = 1 << ip->i_inode.i_blkbits;
320 	error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
321 	if (error)
322 		goto fail;
323 	error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
324 	if (error)
325 		goto fail;
326 	error = -EIO;
327 	if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
328 		goto fail_brelse;
329 
330 	qd->qd_bh = bh;
331 	qd->qd_bh_qc = (struct gfs2_quota_change *)
332 		(bh->b_data + sizeof(struct gfs2_meta_header) +
333 		 offset * sizeof(struct gfs2_quota_change));
334 
335 	mutex_unlock(&sdp->sd_quota_mutex);
336 
337 	return 0;
338 
339 fail_brelse:
340 	brelse(bh);
341 fail:
342 	qd->qd_bh_count--;
343 	mutex_unlock(&sdp->sd_quota_mutex);
344 	return error;
345 }
346 
347 static void bh_put(struct gfs2_quota_data *qd)
348 {
349 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
350 
351 	mutex_lock(&sdp->sd_quota_mutex);
352 	gfs2_assert(sdp, qd->qd_bh_count);
353 	if (!--qd->qd_bh_count) {
354 		brelse(qd->qd_bh);
355 		qd->qd_bh = NULL;
356 		qd->qd_bh_qc = NULL;
357 	}
358 	mutex_unlock(&sdp->sd_quota_mutex);
359 }
360 
361 static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
362 {
363 	struct gfs2_quota_data *qd = NULL;
364 	int error;
365 	int found = 0;
366 
367 	*qdp = NULL;
368 
369 	if (sdp->sd_vfs->s_flags & MS_RDONLY)
370 		return 0;
371 
372 	spin_lock(&qd_lru_lock);
373 
374 	list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
375 		if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
376 		    !test_bit(QDF_CHANGE, &qd->qd_flags) ||
377 		    qd->qd_sync_gen >= sdp->sd_quota_sync_gen)
378 			continue;
379 
380 		list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
381 
382 		set_bit(QDF_LOCKED, &qd->qd_flags);
383 		gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
384 		atomic_inc(&qd->qd_count);
385 		qd->qd_change_sync = qd->qd_change;
386 		gfs2_assert_warn(sdp, qd->qd_slot_count);
387 		qd->qd_slot_count++;
388 		found = 1;
389 
390 		break;
391 	}
392 
393 	if (!found)
394 		qd = NULL;
395 
396 	spin_unlock(&qd_lru_lock);
397 
398 	if (qd) {
399 		gfs2_assert_warn(sdp, qd->qd_change_sync);
400 		error = bh_get(qd);
401 		if (error) {
402 			clear_bit(QDF_LOCKED, &qd->qd_flags);
403 			slot_put(qd);
404 			qd_put(qd);
405 			return error;
406 		}
407 	}
408 
409 	*qdp = qd;
410 
411 	return 0;
412 }
413 
414 static int qd_trylock(struct gfs2_quota_data *qd)
415 {
416 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
417 
418 	if (sdp->sd_vfs->s_flags & MS_RDONLY)
419 		return 0;
420 
421 	spin_lock(&qd_lru_lock);
422 
423 	if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
424 	    !test_bit(QDF_CHANGE, &qd->qd_flags)) {
425 		spin_unlock(&qd_lru_lock);
426 		return 0;
427 	}
428 
429 	list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
430 
431 	set_bit(QDF_LOCKED, &qd->qd_flags);
432 	gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
433 	atomic_inc(&qd->qd_count);
434 	qd->qd_change_sync = qd->qd_change;
435 	gfs2_assert_warn(sdp, qd->qd_slot_count);
436 	qd->qd_slot_count++;
437 
438 	spin_unlock(&qd_lru_lock);
439 
440 	gfs2_assert_warn(sdp, qd->qd_change_sync);
441 	if (bh_get(qd)) {
442 		clear_bit(QDF_LOCKED, &qd->qd_flags);
443 		slot_put(qd);
444 		qd_put(qd);
445 		return 0;
446 	}
447 
448 	return 1;
449 }
450 
451 static void qd_unlock(struct gfs2_quota_data *qd)
452 {
453 	gfs2_assert_warn(qd->qd_gl->gl_sbd,
454 			 test_bit(QDF_LOCKED, &qd->qd_flags));
455 	clear_bit(QDF_LOCKED, &qd->qd_flags);
456 	bh_put(qd);
457 	slot_put(qd);
458 	qd_put(qd);
459 }
460 
461 static int qdsb_get(struct gfs2_sbd *sdp, int user, u32 id,
462 		    struct gfs2_quota_data **qdp)
463 {
464 	int error;
465 
466 	error = qd_get(sdp, user, id, qdp);
467 	if (error)
468 		return error;
469 
470 	error = slot_get(*qdp);
471 	if (error)
472 		goto fail;
473 
474 	error = bh_get(*qdp);
475 	if (error)
476 		goto fail_slot;
477 
478 	return 0;
479 
480 fail_slot:
481 	slot_put(*qdp);
482 fail:
483 	qd_put(*qdp);
484 	return error;
485 }
486 
487 static void qdsb_put(struct gfs2_quota_data *qd)
488 {
489 	bh_put(qd);
490 	slot_put(qd);
491 	qd_put(qd);
492 }
493 
494 int gfs2_quota_hold(struct gfs2_inode *ip, u32 uid, u32 gid)
495 {
496 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
497 	struct gfs2_alloc *al = ip->i_alloc;
498 	struct gfs2_quota_data **qd = al->al_qd;
499 	int error;
500 
501 	if (gfs2_assert_warn(sdp, !al->al_qd_num) ||
502 	    gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
503 		return -EIO;
504 
505 	if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
506 		return 0;
507 
508 	error = qdsb_get(sdp, QUOTA_USER, ip->i_inode.i_uid, qd);
509 	if (error)
510 		goto out;
511 	al->al_qd_num++;
512 	qd++;
513 
514 	error = qdsb_get(sdp, QUOTA_GROUP, ip->i_inode.i_gid, qd);
515 	if (error)
516 		goto out;
517 	al->al_qd_num++;
518 	qd++;
519 
520 	if (uid != NO_QUOTA_CHANGE && uid != ip->i_inode.i_uid) {
521 		error = qdsb_get(sdp, QUOTA_USER, uid, qd);
522 		if (error)
523 			goto out;
524 		al->al_qd_num++;
525 		qd++;
526 	}
527 
528 	if (gid != NO_QUOTA_CHANGE && gid != ip->i_inode.i_gid) {
529 		error = qdsb_get(sdp, QUOTA_GROUP, gid, qd);
530 		if (error)
531 			goto out;
532 		al->al_qd_num++;
533 		qd++;
534 	}
535 
536 out:
537 	if (error)
538 		gfs2_quota_unhold(ip);
539 	return error;
540 }
541 
542 void gfs2_quota_unhold(struct gfs2_inode *ip)
543 {
544 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
545 	struct gfs2_alloc *al = ip->i_alloc;
546 	unsigned int x;
547 
548 	gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
549 
550 	for (x = 0; x < al->al_qd_num; x++) {
551 		qdsb_put(al->al_qd[x]);
552 		al->al_qd[x] = NULL;
553 	}
554 	al->al_qd_num = 0;
555 }
556 
557 static int sort_qd(const void *a, const void *b)
558 {
559 	const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
560 	const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
561 
562 	if (!test_bit(QDF_USER, &qd_a->qd_flags) !=
563 	    !test_bit(QDF_USER, &qd_b->qd_flags)) {
564 		if (test_bit(QDF_USER, &qd_a->qd_flags))
565 			return -1;
566 		else
567 			return 1;
568 	}
569 	if (qd_a->qd_id < qd_b->qd_id)
570 		return -1;
571 	if (qd_a->qd_id > qd_b->qd_id)
572 		return 1;
573 
574 	return 0;
575 }
576 
577 static void do_qc(struct gfs2_quota_data *qd, s64 change)
578 {
579 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
580 	struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
581 	struct gfs2_quota_change *qc = qd->qd_bh_qc;
582 	s64 x;
583 
584 	mutex_lock(&sdp->sd_quota_mutex);
585 	gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
586 
587 	if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
588 		qc->qc_change = 0;
589 		qc->qc_flags = 0;
590 		if (test_bit(QDF_USER, &qd->qd_flags))
591 			qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
592 		qc->qc_id = cpu_to_be32(qd->qd_id);
593 	}
594 
595 	x = be64_to_cpu(qc->qc_change) + change;
596 	qc->qc_change = cpu_to_be64(x);
597 
598 	spin_lock(&qd_lru_lock);
599 	qd->qd_change = x;
600 	spin_unlock(&qd_lru_lock);
601 
602 	if (!x) {
603 		gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
604 		clear_bit(QDF_CHANGE, &qd->qd_flags);
605 		qc->qc_flags = 0;
606 		qc->qc_id = 0;
607 		slot_put(qd);
608 		qd_put(qd);
609 	} else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
610 		qd_hold(qd);
611 		slot_hold(qd);
612 	}
613 
614 	mutex_unlock(&sdp->sd_quota_mutex);
615 }
616 
617 /**
618  * gfs2_adjust_quota - adjust record of current block usage
619  * @ip: The quota inode
620  * @loc: Offset of the entry in the quota file
621  * @change: The amount of usage change to record
622  * @qd: The quota data
623  * @fdq: The updated limits to record
624  *
625  * This function was mostly borrowed from gfs2_block_truncate_page which was
626  * in turn mostly borrowed from ext3
627  *
628  * Returns: 0 or -ve on error
629  */
630 
631 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
632 			     s64 change, struct gfs2_quota_data *qd,
633 			     struct fs_disk_quota *fdq)
634 {
635 	struct inode *inode = &ip->i_inode;
636 	struct gfs2_sbd *sdp = GFS2_SB(inode);
637 	struct address_space *mapping = inode->i_mapping;
638 	unsigned long index = loc >> PAGE_CACHE_SHIFT;
639 	unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
640 	unsigned blocksize, iblock, pos;
641 	struct buffer_head *bh, *dibh;
642 	struct page *page;
643 	void *kaddr, *ptr;
644 	struct gfs2_quota q, *qp;
645 	int err, nbytes;
646 	u64 size;
647 
648 	if (gfs2_is_stuffed(ip))
649 		gfs2_unstuff_dinode(ip, NULL);
650 
651 	memset(&q, 0, sizeof(struct gfs2_quota));
652 	err = gfs2_internal_read(ip, NULL, (char *)&q, &loc, sizeof(q));
653 	if (err < 0)
654 		return err;
655 
656 	err = -EIO;
657 	qp = &q;
658 	qp->qu_value = be64_to_cpu(qp->qu_value);
659 	qp->qu_value += change;
660 	qp->qu_value = cpu_to_be64(qp->qu_value);
661 	qd->qd_qb.qb_value = qp->qu_value;
662 	if (fdq) {
663 		if (fdq->d_fieldmask & FS_DQ_BSOFT) {
664 			qp->qu_warn = cpu_to_be64(fdq->d_blk_softlimit >> sdp->sd_fsb2bb_shift);
665 			qd->qd_qb.qb_warn = qp->qu_warn;
666 		}
667 		if (fdq->d_fieldmask & FS_DQ_BHARD) {
668 			qp->qu_limit = cpu_to_be64(fdq->d_blk_hardlimit >> sdp->sd_fsb2bb_shift);
669 			qd->qd_qb.qb_limit = qp->qu_limit;
670 		}
671 		if (fdq->d_fieldmask & FS_DQ_BCOUNT) {
672 			qp->qu_value = cpu_to_be64(fdq->d_bcount >> sdp->sd_fsb2bb_shift);
673 			qd->qd_qb.qb_value = qp->qu_value;
674 		}
675 	}
676 
677 	/* Write the quota into the quota file on disk */
678 	ptr = qp;
679 	nbytes = sizeof(struct gfs2_quota);
680 get_a_page:
681 	page = grab_cache_page(mapping, index);
682 	if (!page)
683 		return -ENOMEM;
684 
685 	blocksize = inode->i_sb->s_blocksize;
686 	iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
687 
688 	if (!page_has_buffers(page))
689 		create_empty_buffers(page, blocksize, 0);
690 
691 	bh = page_buffers(page);
692 	pos = blocksize;
693 	while (offset >= pos) {
694 		bh = bh->b_this_page;
695 		iblock++;
696 		pos += blocksize;
697 	}
698 
699 	if (!buffer_mapped(bh)) {
700 		gfs2_block_map(inode, iblock, bh, 1);
701 		if (!buffer_mapped(bh))
702 			goto unlock_out;
703 		/* If it's a newly allocated disk block for quota, zero it */
704 		if (buffer_new(bh))
705 			zero_user(page, pos - blocksize, bh->b_size);
706 	}
707 
708 	if (PageUptodate(page))
709 		set_buffer_uptodate(bh);
710 
711 	if (!buffer_uptodate(bh)) {
712 		ll_rw_block(READ_META, 1, &bh);
713 		wait_on_buffer(bh);
714 		if (!buffer_uptodate(bh))
715 			goto unlock_out;
716 	}
717 
718 	gfs2_trans_add_bh(ip->i_gl, bh, 0);
719 
720 	kaddr = kmap_atomic(page, KM_USER0);
721 	if (offset + sizeof(struct gfs2_quota) > PAGE_CACHE_SIZE)
722 		nbytes = PAGE_CACHE_SIZE - offset;
723 	memcpy(kaddr + offset, ptr, nbytes);
724 	flush_dcache_page(page);
725 	kunmap_atomic(kaddr, KM_USER0);
726 	unlock_page(page);
727 	page_cache_release(page);
728 
729 	/* If quota straddles page boundary, we need to update the rest of the
730 	 * quota at the beginning of the next page */
731 	if ((offset + sizeof(struct gfs2_quota)) > PAGE_CACHE_SIZE) {
732 		ptr = ptr + nbytes;
733 		nbytes = sizeof(struct gfs2_quota) - nbytes;
734 		offset = 0;
735 		index++;
736 		goto get_a_page;
737 	}
738 
739 	/* Update the disk inode timestamp and size (if extended) */
740 	err = gfs2_meta_inode_buffer(ip, &dibh);
741 	if (err)
742 		goto out;
743 
744 	size = loc + sizeof(struct gfs2_quota);
745 	if (size > inode->i_size)
746 		i_size_write(inode, size);
747 	inode->i_mtime = inode->i_atime = CURRENT_TIME;
748 	gfs2_trans_add_bh(ip->i_gl, dibh, 1);
749 	gfs2_dinode_out(ip, dibh->b_data);
750 	brelse(dibh);
751 	mark_inode_dirty(inode);
752 
753 out:
754 	return err;
755 unlock_out:
756 	unlock_page(page);
757 	page_cache_release(page);
758 	return err;
759 }
760 
761 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
762 {
763 	struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
764 	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
765 	unsigned int data_blocks, ind_blocks;
766 	struct gfs2_holder *ghs, i_gh;
767 	unsigned int qx, x;
768 	struct gfs2_quota_data *qd;
769 	loff_t offset;
770 	unsigned int nalloc = 0, blocks;
771 	struct gfs2_alloc *al = NULL;
772 	int error;
773 
774 	gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
775 			      &data_blocks, &ind_blocks);
776 
777 	ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
778 	if (!ghs)
779 		return -ENOMEM;
780 
781 	sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
782 	mutex_lock_nested(&ip->i_inode.i_mutex, I_MUTEX_QUOTA);
783 	for (qx = 0; qx < num_qd; qx++) {
784 		error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
785 					   GL_NOCACHE, &ghs[qx]);
786 		if (error)
787 			goto out;
788 	}
789 
790 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
791 	if (error)
792 		goto out;
793 
794 	for (x = 0; x < num_qd; x++) {
795 		offset = qd2offset(qda[x]);
796 		if (gfs2_write_alloc_required(ip, offset,
797 					      sizeof(struct gfs2_quota)))
798 			nalloc++;
799 	}
800 
801 	al = gfs2_alloc_get(ip);
802 	if (!al) {
803 		error = -ENOMEM;
804 		goto out_gunlock;
805 	}
806 	/*
807 	 * 1 blk for unstuffing inode if stuffed. We add this extra
808 	 * block to the reservation unconditionally. If the inode
809 	 * doesn't need unstuffing, the block will be released to the
810 	 * rgrp since it won't be allocated during the transaction
811 	 */
812 	al->al_requested = 1;
813 	/* +3 in the end for unstuffing block, inode size update block
814 	 * and another block in case quota straddles page boundary and
815 	 * two blocks need to be updated instead of 1 */
816 	blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
817 
818 	if (nalloc)
819 		al->al_requested += nalloc * (data_blocks + ind_blocks);
820 	error = gfs2_inplace_reserve(ip);
821 	if (error)
822 		goto out_alloc;
823 
824 	if (nalloc)
825 		blocks += gfs2_rg_blocks(al) + nalloc * ind_blocks + RES_STATFS;
826 
827 	error = gfs2_trans_begin(sdp, blocks, 0);
828 	if (error)
829 		goto out_ipres;
830 
831 	for (x = 0; x < num_qd; x++) {
832 		qd = qda[x];
833 		offset = qd2offset(qd);
834 		error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
835 		if (error)
836 			goto out_end_trans;
837 
838 		do_qc(qd, -qd->qd_change_sync);
839 		set_bit(QDF_REFRESH, &qd->qd_flags);
840 	}
841 
842 	error = 0;
843 
844 out_end_trans:
845 	gfs2_trans_end(sdp);
846 out_ipres:
847 	gfs2_inplace_release(ip);
848 out_alloc:
849 	gfs2_alloc_put(ip);
850 out_gunlock:
851 	gfs2_glock_dq_uninit(&i_gh);
852 out:
853 	while (qx--)
854 		gfs2_glock_dq_uninit(&ghs[qx]);
855 	mutex_unlock(&ip->i_inode.i_mutex);
856 	kfree(ghs);
857 	gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
858 	return error;
859 }
860 
861 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
862 {
863 	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
864 	struct gfs2_quota q;
865 	struct gfs2_quota_lvb *qlvb;
866 	loff_t pos;
867 	int error;
868 
869 	memset(&q, 0, sizeof(struct gfs2_quota));
870 	pos = qd2offset(qd);
871 	error = gfs2_internal_read(ip, NULL, (char *)&q, &pos, sizeof(q));
872 	if (error < 0)
873 		return error;
874 
875 	qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
876 	qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
877 	qlvb->__pad = 0;
878 	qlvb->qb_limit = q.qu_limit;
879 	qlvb->qb_warn = q.qu_warn;
880 	qlvb->qb_value = q.qu_value;
881 	qd->qd_qb = *qlvb;
882 
883 	return 0;
884 }
885 
886 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
887 		    struct gfs2_holder *q_gh)
888 {
889 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
890 	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
891 	struct gfs2_holder i_gh;
892 	int error;
893 
894 restart:
895 	error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
896 	if (error)
897 		return error;
898 
899 	qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
900 
901 	if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
902 		gfs2_glock_dq_uninit(q_gh);
903 		error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
904 					   GL_NOCACHE, q_gh);
905 		if (error)
906 			return error;
907 
908 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
909 		if (error)
910 			goto fail;
911 
912 		error = update_qd(sdp, qd);
913 		if (error)
914 			goto fail_gunlock;
915 
916 		gfs2_glock_dq_uninit(&i_gh);
917 		gfs2_glock_dq_uninit(q_gh);
918 		force_refresh = 0;
919 		goto restart;
920 	}
921 
922 	return 0;
923 
924 fail_gunlock:
925 	gfs2_glock_dq_uninit(&i_gh);
926 fail:
927 	gfs2_glock_dq_uninit(q_gh);
928 	return error;
929 }
930 
931 int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
932 {
933 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
934 	struct gfs2_alloc *al = ip->i_alloc;
935 	struct gfs2_quota_data *qd;
936 	unsigned int x;
937 	int error = 0;
938 
939 	gfs2_quota_hold(ip, uid, gid);
940 
941 	if (capable(CAP_SYS_RESOURCE) ||
942 	    sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
943 		return 0;
944 
945 	sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
946 	     sort_qd, NULL);
947 
948 	for (x = 0; x < al->al_qd_num; x++) {
949 		int force = NO_FORCE;
950 		qd = al->al_qd[x];
951 		if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
952 			force = FORCE;
953 		error = do_glock(qd, force, &al->al_qd_ghs[x]);
954 		if (error)
955 			break;
956 	}
957 
958 	if (!error)
959 		set_bit(GIF_QD_LOCKED, &ip->i_flags);
960 	else {
961 		while (x--)
962 			gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
963 		gfs2_quota_unhold(ip);
964 	}
965 
966 	return error;
967 }
968 
969 static int need_sync(struct gfs2_quota_data *qd)
970 {
971 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
972 	struct gfs2_tune *gt = &sdp->sd_tune;
973 	s64 value;
974 	unsigned int num, den;
975 	int do_sync = 1;
976 
977 	if (!qd->qd_qb.qb_limit)
978 		return 0;
979 
980 	spin_lock(&qd_lru_lock);
981 	value = qd->qd_change;
982 	spin_unlock(&qd_lru_lock);
983 
984 	spin_lock(&gt->gt_spin);
985 	num = gt->gt_quota_scale_num;
986 	den = gt->gt_quota_scale_den;
987 	spin_unlock(&gt->gt_spin);
988 
989 	if (value < 0)
990 		do_sync = 0;
991 	else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
992 		 (s64)be64_to_cpu(qd->qd_qb.qb_limit))
993 		do_sync = 0;
994 	else {
995 		value *= gfs2_jindex_size(sdp) * num;
996 		value = div_s64(value, den);
997 		value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
998 		if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
999 			do_sync = 0;
1000 	}
1001 
1002 	return do_sync;
1003 }
1004 
1005 void gfs2_quota_unlock(struct gfs2_inode *ip)
1006 {
1007 	struct gfs2_alloc *al = ip->i_alloc;
1008 	struct gfs2_quota_data *qda[4];
1009 	unsigned int count = 0;
1010 	unsigned int x;
1011 
1012 	if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1013 		goto out;
1014 
1015 	for (x = 0; x < al->al_qd_num; x++) {
1016 		struct gfs2_quota_data *qd;
1017 		int sync;
1018 
1019 		qd = al->al_qd[x];
1020 		sync = need_sync(qd);
1021 
1022 		gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
1023 
1024 		if (sync && qd_trylock(qd))
1025 			qda[count++] = qd;
1026 	}
1027 
1028 	if (count) {
1029 		do_sync(count, qda);
1030 		for (x = 0; x < count; x++)
1031 			qd_unlock(qda[x]);
1032 	}
1033 
1034 out:
1035 	gfs2_quota_unhold(ip);
1036 }
1037 
1038 #define MAX_LINE 256
1039 
1040 static int print_message(struct gfs2_quota_data *qd, char *type)
1041 {
1042 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
1043 
1044 	printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\n",
1045 	       sdp->sd_fsname, type,
1046 	       (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
1047 	       qd->qd_id);
1048 
1049 	return 0;
1050 }
1051 
1052 int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
1053 {
1054 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1055 	struct gfs2_alloc *al = ip->i_alloc;
1056 	struct gfs2_quota_data *qd;
1057 	s64 value;
1058 	unsigned int x;
1059 	int error = 0;
1060 
1061 	if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1062 		return 0;
1063 
1064         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1065                 return 0;
1066 
1067 	for (x = 0; x < al->al_qd_num; x++) {
1068 		qd = al->al_qd[x];
1069 
1070 		if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1071 		      (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
1072 			continue;
1073 
1074 		value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1075 		spin_lock(&qd_lru_lock);
1076 		value += qd->qd_change;
1077 		spin_unlock(&qd_lru_lock);
1078 
1079 		if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
1080 			print_message(qd, "exceeded");
1081 			quota_send_warning(test_bit(QDF_USER, &qd->qd_flags) ?
1082 					   USRQUOTA : GRPQUOTA, qd->qd_id,
1083 					   sdp->sd_vfs->s_dev, QUOTA_NL_BHARDWARN);
1084 
1085 			error = -EDQUOT;
1086 			break;
1087 		} else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
1088 			   (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
1089 			   time_after_eq(jiffies, qd->qd_last_warn +
1090 					 gfs2_tune_get(sdp,
1091 						gt_quota_warn_period) * HZ)) {
1092 			quota_send_warning(test_bit(QDF_USER, &qd->qd_flags) ?
1093 					   USRQUOTA : GRPQUOTA, qd->qd_id,
1094 					   sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1095 			error = print_message(qd, "warning");
1096 			qd->qd_last_warn = jiffies;
1097 		}
1098 	}
1099 
1100 	return error;
1101 }
1102 
1103 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1104 		       u32 uid, u32 gid)
1105 {
1106 	struct gfs2_alloc *al = ip->i_alloc;
1107 	struct gfs2_quota_data *qd;
1108 	unsigned int x;
1109 
1110 	if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1111 		return;
1112 	if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1113 		return;
1114 
1115 	for (x = 0; x < al->al_qd_num; x++) {
1116 		qd = al->al_qd[x];
1117 
1118 		if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1119 		    (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
1120 			do_qc(qd, change);
1121 		}
1122 	}
1123 }
1124 
1125 int gfs2_quota_sync(struct super_block *sb, int type, int wait)
1126 {
1127 	struct gfs2_sbd *sdp = sb->s_fs_info;
1128 	struct gfs2_quota_data **qda;
1129 	unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
1130 	unsigned int num_qd;
1131 	unsigned int x;
1132 	int error = 0;
1133 
1134 	sdp->sd_quota_sync_gen++;
1135 
1136 	qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1137 	if (!qda)
1138 		return -ENOMEM;
1139 
1140 	do {
1141 		num_qd = 0;
1142 
1143 		for (;;) {
1144 			error = qd_fish(sdp, qda + num_qd);
1145 			if (error || !qda[num_qd])
1146 				break;
1147 			if (++num_qd == max_qd)
1148 				break;
1149 		}
1150 
1151 		if (num_qd) {
1152 			if (!error)
1153 				error = do_sync(num_qd, qda);
1154 			if (!error)
1155 				for (x = 0; x < num_qd; x++)
1156 					qda[x]->qd_sync_gen =
1157 						sdp->sd_quota_sync_gen;
1158 
1159 			for (x = 0; x < num_qd; x++)
1160 				qd_unlock(qda[x]);
1161 		}
1162 	} while (!error && num_qd == max_qd);
1163 
1164 	kfree(qda);
1165 
1166 	return error;
1167 }
1168 
1169 static int gfs2_quota_sync_timeo(struct super_block *sb, int type)
1170 {
1171 	return gfs2_quota_sync(sb, type, 0);
1172 }
1173 
1174 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
1175 {
1176 	struct gfs2_quota_data *qd;
1177 	struct gfs2_holder q_gh;
1178 	int error;
1179 
1180 	error = qd_get(sdp, user, id, &qd);
1181 	if (error)
1182 		return error;
1183 
1184 	error = do_glock(qd, FORCE, &q_gh);
1185 	if (!error)
1186 		gfs2_glock_dq_uninit(&q_gh);
1187 
1188 	qd_put(qd);
1189 	return error;
1190 }
1191 
1192 static void gfs2_quota_change_in(struct gfs2_quota_change_host *qc, const void *buf)
1193 {
1194 	const struct gfs2_quota_change *str = buf;
1195 
1196 	qc->qc_change = be64_to_cpu(str->qc_change);
1197 	qc->qc_flags = be32_to_cpu(str->qc_flags);
1198 	qc->qc_id = be32_to_cpu(str->qc_id);
1199 }
1200 
1201 int gfs2_quota_init(struct gfs2_sbd *sdp)
1202 {
1203 	struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1204 	u64 size = i_size_read(sdp->sd_qc_inode);
1205 	unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1206 	unsigned int x, slot = 0;
1207 	unsigned int found = 0;
1208 	u64 dblock;
1209 	u32 extlen = 0;
1210 	int error;
1211 
1212 	if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1213 		return -EIO;
1214 
1215 	sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1216 	sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1217 
1218 	error = -ENOMEM;
1219 
1220 	sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1221 				       sizeof(unsigned char *), GFP_NOFS);
1222 	if (!sdp->sd_quota_bitmap)
1223 		return error;
1224 
1225 	for (x = 0; x < sdp->sd_quota_chunks; x++) {
1226 		sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_NOFS);
1227 		if (!sdp->sd_quota_bitmap[x])
1228 			goto fail;
1229 	}
1230 
1231 	for (x = 0; x < blocks; x++) {
1232 		struct buffer_head *bh;
1233 		unsigned int y;
1234 
1235 		if (!extlen) {
1236 			int new = 0;
1237 			error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1238 			if (error)
1239 				goto fail;
1240 		}
1241 		error = -EIO;
1242 		bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1243 		if (!bh)
1244 			goto fail;
1245 		if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1246 			brelse(bh);
1247 			goto fail;
1248 		}
1249 
1250 		for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1251 		     y++, slot++) {
1252 			struct gfs2_quota_change_host qc;
1253 			struct gfs2_quota_data *qd;
1254 
1255 			gfs2_quota_change_in(&qc, bh->b_data +
1256 					  sizeof(struct gfs2_meta_header) +
1257 					  y * sizeof(struct gfs2_quota_change));
1258 			if (!qc.qc_change)
1259 				continue;
1260 
1261 			error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1262 					 qc.qc_id, &qd);
1263 			if (error) {
1264 				brelse(bh);
1265 				goto fail;
1266 			}
1267 
1268 			set_bit(QDF_CHANGE, &qd->qd_flags);
1269 			qd->qd_change = qc.qc_change;
1270 			qd->qd_slot = slot;
1271 			qd->qd_slot_count = 1;
1272 
1273 			spin_lock(&qd_lru_lock);
1274 			gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1275 			list_add(&qd->qd_list, &sdp->sd_quota_list);
1276 			atomic_inc(&sdp->sd_quota_count);
1277 			spin_unlock(&qd_lru_lock);
1278 
1279 			found++;
1280 		}
1281 
1282 		brelse(bh);
1283 		dblock++;
1284 		extlen--;
1285 	}
1286 
1287 	if (found)
1288 		fs_info(sdp, "found %u quota changes\n", found);
1289 
1290 	return 0;
1291 
1292 fail:
1293 	gfs2_quota_cleanup(sdp);
1294 	return error;
1295 }
1296 
1297 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1298 {
1299 	struct list_head *head = &sdp->sd_quota_list;
1300 	struct gfs2_quota_data *qd;
1301 	unsigned int x;
1302 
1303 	spin_lock(&qd_lru_lock);
1304 	while (!list_empty(head)) {
1305 		qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1306 
1307 		if (atomic_read(&qd->qd_count) > 1 ||
1308 		    (atomic_read(&qd->qd_count) &&
1309 		     !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1310 			list_move(&qd->qd_list, head);
1311 			spin_unlock(&qd_lru_lock);
1312 			schedule();
1313 			spin_lock(&qd_lru_lock);
1314 			continue;
1315 		}
1316 
1317 		list_del(&qd->qd_list);
1318 		/* Also remove if this qd exists in the reclaim list */
1319 		if (!list_empty(&qd->qd_reclaim)) {
1320 			list_del_init(&qd->qd_reclaim);
1321 			atomic_dec(&qd_lru_count);
1322 		}
1323 		atomic_dec(&sdp->sd_quota_count);
1324 		spin_unlock(&qd_lru_lock);
1325 
1326 		if (!atomic_read(&qd->qd_count)) {
1327 			gfs2_assert_warn(sdp, !qd->qd_change);
1328 			gfs2_assert_warn(sdp, !qd->qd_slot_count);
1329 		} else
1330 			gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1331 		gfs2_assert_warn(sdp, !qd->qd_bh_count);
1332 
1333 		gfs2_glock_put(qd->qd_gl);
1334 		kmem_cache_free(gfs2_quotad_cachep, qd);
1335 
1336 		spin_lock(&qd_lru_lock);
1337 	}
1338 	spin_unlock(&qd_lru_lock);
1339 
1340 	gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1341 
1342 	if (sdp->sd_quota_bitmap) {
1343 		for (x = 0; x < sdp->sd_quota_chunks; x++)
1344 			kfree(sdp->sd_quota_bitmap[x]);
1345 		kfree(sdp->sd_quota_bitmap);
1346 	}
1347 }
1348 
1349 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1350 {
1351 	if (error == 0 || error == -EROFS)
1352 		return;
1353 	if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1354 		fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1355 }
1356 
1357 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1358 			       int (*fxn)(struct super_block *sb, int type),
1359 			       unsigned long t, unsigned long *timeo,
1360 			       unsigned int *new_timeo)
1361 {
1362 	if (t >= *timeo) {
1363 		int error = fxn(sdp->sd_vfs, 0);
1364 		quotad_error(sdp, msg, error);
1365 		*timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1366 	} else {
1367 		*timeo -= t;
1368 	}
1369 }
1370 
1371 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1372 {
1373 	struct gfs2_inode *ip;
1374 
1375 	while(1) {
1376 		ip = NULL;
1377 		spin_lock(&sdp->sd_trunc_lock);
1378 		if (!list_empty(&sdp->sd_trunc_list)) {
1379 			ip = list_entry(sdp->sd_trunc_list.next,
1380 					struct gfs2_inode, i_trunc_list);
1381 			list_del_init(&ip->i_trunc_list);
1382 		}
1383 		spin_unlock(&sdp->sd_trunc_lock);
1384 		if (ip == NULL)
1385 			return;
1386 		gfs2_glock_finish_truncate(ip);
1387 	}
1388 }
1389 
1390 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1391 	if (!sdp->sd_statfs_force_sync) {
1392 		sdp->sd_statfs_force_sync = 1;
1393 		wake_up(&sdp->sd_quota_wait);
1394 	}
1395 }
1396 
1397 
1398 /**
1399  * gfs2_quotad - Write cached quota changes into the quota file
1400  * @sdp: Pointer to GFS2 superblock
1401  *
1402  */
1403 
1404 int gfs2_quotad(void *data)
1405 {
1406 	struct gfs2_sbd *sdp = data;
1407 	struct gfs2_tune *tune = &sdp->sd_tune;
1408 	unsigned long statfs_timeo = 0;
1409 	unsigned long quotad_timeo = 0;
1410 	unsigned long t = 0;
1411 	DEFINE_WAIT(wait);
1412 	int empty;
1413 
1414 	while (!kthread_should_stop()) {
1415 
1416 		/* Update the master statfs file */
1417 		if (sdp->sd_statfs_force_sync) {
1418 			int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1419 			quotad_error(sdp, "statfs", error);
1420 			statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1421 		}
1422 		else
1423 			quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1424 				   	   &statfs_timeo,
1425 					   &tune->gt_statfs_quantum);
1426 
1427 		/* Update quota file */
1428 		quotad_check_timeo(sdp, "sync", gfs2_quota_sync_timeo, t,
1429 				   &quotad_timeo, &tune->gt_quota_quantum);
1430 
1431 		/* Check for & recover partially truncated inodes */
1432 		quotad_check_trunc_list(sdp);
1433 
1434 		if (freezing(current))
1435 			refrigerator();
1436 		t = min(quotad_timeo, statfs_timeo);
1437 
1438 		prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1439 		spin_lock(&sdp->sd_trunc_lock);
1440 		empty = list_empty(&sdp->sd_trunc_list);
1441 		spin_unlock(&sdp->sd_trunc_lock);
1442 		if (empty && !sdp->sd_statfs_force_sync)
1443 			t -= schedule_timeout(t);
1444 		else
1445 			t = 0;
1446 		finish_wait(&sdp->sd_quota_wait, &wait);
1447 	}
1448 
1449 	return 0;
1450 }
1451 
1452 static int gfs2_quota_get_xstate(struct super_block *sb,
1453 				 struct fs_quota_stat *fqs)
1454 {
1455 	struct gfs2_sbd *sdp = sb->s_fs_info;
1456 
1457 	memset(fqs, 0, sizeof(struct fs_quota_stat));
1458 	fqs->qs_version = FS_QSTAT_VERSION;
1459 
1460 	switch (sdp->sd_args.ar_quota) {
1461 	case GFS2_QUOTA_ON:
1462 		fqs->qs_flags |= (FS_QUOTA_UDQ_ENFD | FS_QUOTA_GDQ_ENFD);
1463 		/*FALLTHRU*/
1464 	case GFS2_QUOTA_ACCOUNT:
1465 		fqs->qs_flags |= (FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT);
1466 		break;
1467 	case GFS2_QUOTA_OFF:
1468 		break;
1469 	}
1470 
1471 	if (sdp->sd_quota_inode) {
1472 		fqs->qs_uquota.qfs_ino = GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1473 		fqs->qs_uquota.qfs_nblks = sdp->sd_quota_inode->i_blocks;
1474 	}
1475 	fqs->qs_uquota.qfs_nextents = 1; /* unsupported */
1476 	fqs->qs_gquota = fqs->qs_uquota; /* its the same inode in both cases */
1477 	fqs->qs_incoredqs = atomic_read(&qd_lru_count);
1478 	return 0;
1479 }
1480 
1481 static int gfs2_get_dqblk(struct super_block *sb, int type, qid_t id,
1482 			  struct fs_disk_quota *fdq)
1483 {
1484 	struct gfs2_sbd *sdp = sb->s_fs_info;
1485 	struct gfs2_quota_lvb *qlvb;
1486 	struct gfs2_quota_data *qd;
1487 	struct gfs2_holder q_gh;
1488 	int error;
1489 
1490 	memset(fdq, 0, sizeof(struct fs_disk_quota));
1491 
1492 	if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1493 		return -ESRCH; /* Crazy XFS error code */
1494 
1495 	if (type == USRQUOTA)
1496 		type = QUOTA_USER;
1497 	else if (type == GRPQUOTA)
1498 		type = QUOTA_GROUP;
1499 	else
1500 		return -EINVAL;
1501 
1502 	error = qd_get(sdp, type, id, &qd);
1503 	if (error)
1504 		return error;
1505 	error = do_glock(qd, FORCE, &q_gh);
1506 	if (error)
1507 		goto out;
1508 
1509 	qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
1510 	fdq->d_version = FS_DQUOT_VERSION;
1511 	fdq->d_flags = (type == QUOTA_USER) ? FS_USER_QUOTA : FS_GROUP_QUOTA;
1512 	fdq->d_id = id;
1513 	fdq->d_blk_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_fsb2bb_shift;
1514 	fdq->d_blk_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_fsb2bb_shift;
1515 	fdq->d_bcount = be64_to_cpu(qlvb->qb_value) << sdp->sd_fsb2bb_shift;
1516 
1517 	gfs2_glock_dq_uninit(&q_gh);
1518 out:
1519 	qd_put(qd);
1520 	return error;
1521 }
1522 
1523 /* GFS2 only supports a subset of the XFS fields */
1524 #define GFS2_FIELDMASK (FS_DQ_BSOFT|FS_DQ_BHARD|FS_DQ_BCOUNT)
1525 
1526 static int gfs2_set_dqblk(struct super_block *sb, int type, qid_t id,
1527 			  struct fs_disk_quota *fdq)
1528 {
1529 	struct gfs2_sbd *sdp = sb->s_fs_info;
1530 	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1531 	struct gfs2_quota_data *qd;
1532 	struct gfs2_holder q_gh, i_gh;
1533 	unsigned int data_blocks, ind_blocks;
1534 	unsigned int blocks = 0;
1535 	int alloc_required;
1536 	struct gfs2_alloc *al;
1537 	loff_t offset;
1538 	int error;
1539 
1540 	if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1541 		return -ESRCH; /* Crazy XFS error code */
1542 
1543 	switch(type) {
1544 	case USRQUOTA:
1545 		type = QUOTA_USER;
1546 		if (fdq->d_flags != FS_USER_QUOTA)
1547 			return -EINVAL;
1548 		break;
1549 	case GRPQUOTA:
1550 		type = QUOTA_GROUP;
1551 		if (fdq->d_flags != FS_GROUP_QUOTA)
1552 			return -EINVAL;
1553 		break;
1554 	default:
1555 		return -EINVAL;
1556 	}
1557 
1558 	if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1559 		return -EINVAL;
1560 	if (fdq->d_id != id)
1561 		return -EINVAL;
1562 
1563 	error = qd_get(sdp, type, id, &qd);
1564 	if (error)
1565 		return error;
1566 
1567 	mutex_lock(&ip->i_inode.i_mutex);
1568 	error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1569 	if (error)
1570 		goto out_put;
1571 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1572 	if (error)
1573 		goto out_q;
1574 
1575 	/* Check for existing entry, if none then alloc new blocks */
1576 	error = update_qd(sdp, qd);
1577 	if (error)
1578 		goto out_i;
1579 
1580 	/* If nothing has changed, this is a no-op */
1581 	if ((fdq->d_fieldmask & FS_DQ_BSOFT) &&
1582 	    ((fdq->d_blk_softlimit >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1583 		fdq->d_fieldmask ^= FS_DQ_BSOFT;
1584 
1585 	if ((fdq->d_fieldmask & FS_DQ_BHARD) &&
1586 	    ((fdq->d_blk_hardlimit >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1587 		fdq->d_fieldmask ^= FS_DQ_BHARD;
1588 
1589 	if ((fdq->d_fieldmask & FS_DQ_BCOUNT) &&
1590 	    ((fdq->d_bcount >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1591 		fdq->d_fieldmask ^= FS_DQ_BCOUNT;
1592 
1593 	if (fdq->d_fieldmask == 0)
1594 		goto out_i;
1595 
1596 	offset = qd2offset(qd);
1597 	alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1598 	if (gfs2_is_stuffed(ip))
1599 		alloc_required = 1;
1600 	if (alloc_required) {
1601 		al = gfs2_alloc_get(ip);
1602 		if (al == NULL)
1603 			goto out_i;
1604 		gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1605 				       &data_blocks, &ind_blocks);
1606 		blocks = al->al_requested = 1 + data_blocks + ind_blocks;
1607 		error = gfs2_inplace_reserve(ip);
1608 		if (error)
1609 			goto out_alloc;
1610 		blocks += gfs2_rg_blocks(al);
1611 	}
1612 
1613 	/* Some quotas span block boundaries and can update two blocks,
1614 	   adding an extra block to the transaction to handle such quotas */
1615 	error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1616 	if (error)
1617 		goto out_release;
1618 
1619 	/* Apply changes */
1620 	error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1621 
1622 	gfs2_trans_end(sdp);
1623 out_release:
1624 	if (alloc_required) {
1625 		gfs2_inplace_release(ip);
1626 out_alloc:
1627 		gfs2_alloc_put(ip);
1628 	}
1629 out_i:
1630 	gfs2_glock_dq_uninit(&i_gh);
1631 out_q:
1632 	gfs2_glock_dq_uninit(&q_gh);
1633 out_put:
1634 	mutex_unlock(&ip->i_inode.i_mutex);
1635 	qd_put(qd);
1636 	return error;
1637 }
1638 
1639 const struct quotactl_ops gfs2_quotactl_ops = {
1640 	.quota_sync     = gfs2_quota_sync,
1641 	.get_xstate     = gfs2_quota_get_xstate,
1642 	.get_dqblk	= gfs2_get_dqblk,
1643 	.set_dqblk	= gfs2_set_dqblk,
1644 };
1645