xref: /openbmc/linux/fs/gfs2/quota.c (revision b6dcefde)
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;
641 	struct gfs2_quota *qp;
642 	s64 value;
643 	int err = -EIO;
644 	u64 size;
645 
646 	if (gfs2_is_stuffed(ip))
647 		gfs2_unstuff_dinode(ip, NULL);
648 
649 	page = grab_cache_page(mapping, index);
650 	if (!page)
651 		return -ENOMEM;
652 
653 	blocksize = inode->i_sb->s_blocksize;
654 	iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
655 
656 	if (!page_has_buffers(page))
657 		create_empty_buffers(page, blocksize, 0);
658 
659 	bh = page_buffers(page);
660 	pos = blocksize;
661 	while (offset >= pos) {
662 		bh = bh->b_this_page;
663 		iblock++;
664 		pos += blocksize;
665 	}
666 
667 	if (!buffer_mapped(bh)) {
668 		gfs2_block_map(inode, iblock, bh, 1);
669 		if (!buffer_mapped(bh))
670 			goto unlock;
671 	}
672 
673 	if (PageUptodate(page))
674 		set_buffer_uptodate(bh);
675 
676 	if (!buffer_uptodate(bh)) {
677 		ll_rw_block(READ_META, 1, &bh);
678 		wait_on_buffer(bh);
679 		if (!buffer_uptodate(bh))
680 			goto unlock;
681 	}
682 
683 	gfs2_trans_add_bh(ip->i_gl, bh, 0);
684 
685 	kaddr = kmap_atomic(page, KM_USER0);
686 	qp = kaddr + offset;
687 	value = (s64)be64_to_cpu(qp->qu_value) + change;
688 	qp->qu_value = cpu_to_be64(value);
689 	qd->qd_qb.qb_value = qp->qu_value;
690 	if (fdq) {
691 		if (fdq->d_fieldmask & FS_DQ_BSOFT) {
692 			qp->qu_warn = cpu_to_be64(fdq->d_blk_softlimit);
693 			qd->qd_qb.qb_warn = qp->qu_warn;
694 		}
695 		if (fdq->d_fieldmask & FS_DQ_BHARD) {
696 			qp->qu_limit = cpu_to_be64(fdq->d_blk_hardlimit);
697 			qd->qd_qb.qb_limit = qp->qu_limit;
698 		}
699 	}
700 	flush_dcache_page(page);
701 	kunmap_atomic(kaddr, KM_USER0);
702 
703 	err = gfs2_meta_inode_buffer(ip, &dibh);
704 	if (err)
705 		goto unlock;
706 
707 	size = loc + sizeof(struct gfs2_quota);
708 	if (size > inode->i_size) {
709 		ip->i_disksize = size;
710 		i_size_write(inode, size);
711 	}
712 	inode->i_mtime = inode->i_atime = CURRENT_TIME;
713 	gfs2_trans_add_bh(ip->i_gl, dibh, 1);
714 	gfs2_dinode_out(ip, dibh->b_data);
715 	brelse(dibh);
716 	mark_inode_dirty(inode);
717 
718 unlock:
719 	unlock_page(page);
720 	page_cache_release(page);
721 	return err;
722 }
723 
724 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
725 {
726 	struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
727 	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
728 	unsigned int data_blocks, ind_blocks;
729 	struct gfs2_holder *ghs, i_gh;
730 	unsigned int qx, x;
731 	struct gfs2_quota_data *qd;
732 	loff_t offset;
733 	unsigned int nalloc = 0, blocks;
734 	struct gfs2_alloc *al = NULL;
735 	int error;
736 
737 	gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
738 			      &data_blocks, &ind_blocks);
739 
740 	ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
741 	if (!ghs)
742 		return -ENOMEM;
743 
744 	sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
745 	mutex_lock_nested(&ip->i_inode.i_mutex, I_MUTEX_QUOTA);
746 	for (qx = 0; qx < num_qd; qx++) {
747 		error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
748 					   GL_NOCACHE, &ghs[qx]);
749 		if (error)
750 			goto out;
751 	}
752 
753 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
754 	if (error)
755 		goto out;
756 
757 	for (x = 0; x < num_qd; x++) {
758 		int alloc_required;
759 
760 		offset = qd2offset(qda[x]);
761 		error = gfs2_write_alloc_required(ip, offset,
762 						  sizeof(struct gfs2_quota),
763 						  &alloc_required);
764 		if (error)
765 			goto out_gunlock;
766 		if (alloc_required)
767 			nalloc++;
768 	}
769 
770 	al = gfs2_alloc_get(ip);
771 	if (!al) {
772 		error = -ENOMEM;
773 		goto out_gunlock;
774 	}
775 	/*
776 	 * 1 blk for unstuffing inode if stuffed. We add this extra
777 	 * block to the reservation unconditionally. If the inode
778 	 * doesn't need unstuffing, the block will be released to the
779 	 * rgrp since it won't be allocated during the transaction
780 	 */
781 	al->al_requested = 1;
782 	/* +1 in the end for block requested above for unstuffing */
783 	blocks = num_qd * data_blocks + RES_DINODE + num_qd + 1;
784 
785 	if (nalloc)
786 		al->al_requested += nalloc * (data_blocks + ind_blocks);
787 	error = gfs2_inplace_reserve(ip);
788 	if (error)
789 		goto out_alloc;
790 
791 	if (nalloc)
792 		blocks += al->al_rgd->rd_length + nalloc * ind_blocks + RES_STATFS;
793 
794 	error = gfs2_trans_begin(sdp, blocks, 0);
795 	if (error)
796 		goto out_ipres;
797 
798 	for (x = 0; x < num_qd; x++) {
799 		qd = qda[x];
800 		offset = qd2offset(qd);
801 		error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
802 		if (error)
803 			goto out_end_trans;
804 
805 		do_qc(qd, -qd->qd_change_sync);
806 	}
807 
808 	error = 0;
809 
810 out_end_trans:
811 	gfs2_trans_end(sdp);
812 out_ipres:
813 	gfs2_inplace_release(ip);
814 out_alloc:
815 	gfs2_alloc_put(ip);
816 out_gunlock:
817 	gfs2_glock_dq_uninit(&i_gh);
818 out:
819 	while (qx--)
820 		gfs2_glock_dq_uninit(&ghs[qx]);
821 	mutex_unlock(&ip->i_inode.i_mutex);
822 	kfree(ghs);
823 	gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
824 	return error;
825 }
826 
827 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
828 {
829 	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
830 	struct gfs2_quota q;
831 	struct gfs2_quota_lvb *qlvb;
832 	loff_t pos;
833 	int error;
834 
835 	memset(&q, 0, sizeof(struct gfs2_quota));
836 	pos = qd2offset(qd);
837 	error = gfs2_internal_read(ip, NULL, (char *)&q, &pos, sizeof(q));
838 	if (error < 0)
839 		return error;
840 
841 	qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
842 	qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
843 	qlvb->__pad = 0;
844 	qlvb->qb_limit = q.qu_limit;
845 	qlvb->qb_warn = q.qu_warn;
846 	qlvb->qb_value = q.qu_value;
847 	qd->qd_qb = *qlvb;
848 
849 	return 0;
850 }
851 
852 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
853 		    struct gfs2_holder *q_gh)
854 {
855 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
856 	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
857 	struct gfs2_holder i_gh;
858 	int error;
859 
860 restart:
861 	error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
862 	if (error)
863 		return error;
864 
865 	qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
866 
867 	if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
868 		gfs2_glock_dq_uninit(q_gh);
869 		error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
870 					   GL_NOCACHE, q_gh);
871 		if (error)
872 			return error;
873 
874 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
875 		if (error)
876 			goto fail;
877 
878 		error = update_qd(sdp, qd);
879 		if (error)
880 			goto fail_gunlock;
881 
882 		gfs2_glock_dq_uninit(&i_gh);
883 		gfs2_glock_dq_uninit(q_gh);
884 		force_refresh = 0;
885 		goto restart;
886 	}
887 
888 	return 0;
889 
890 fail_gunlock:
891 	gfs2_glock_dq_uninit(&i_gh);
892 fail:
893 	gfs2_glock_dq_uninit(q_gh);
894 	return error;
895 }
896 
897 int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
898 {
899 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
900 	struct gfs2_alloc *al = ip->i_alloc;
901 	unsigned int x;
902 	int error = 0;
903 
904 	gfs2_quota_hold(ip, uid, gid);
905 
906 	if (capable(CAP_SYS_RESOURCE) ||
907 	    sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
908 		return 0;
909 
910 	sort(al->al_qd, al->al_qd_num, sizeof(struct gfs2_quota_data *),
911 	     sort_qd, NULL);
912 
913 	for (x = 0; x < al->al_qd_num; x++) {
914 		error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
915 		if (error)
916 			break;
917 	}
918 
919 	if (!error)
920 		set_bit(GIF_QD_LOCKED, &ip->i_flags);
921 	else {
922 		while (x--)
923 			gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
924 		gfs2_quota_unhold(ip);
925 	}
926 
927 	return error;
928 }
929 
930 static int need_sync(struct gfs2_quota_data *qd)
931 {
932 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
933 	struct gfs2_tune *gt = &sdp->sd_tune;
934 	s64 value;
935 	unsigned int num, den;
936 	int do_sync = 1;
937 
938 	if (!qd->qd_qb.qb_limit)
939 		return 0;
940 
941 	spin_lock(&qd_lru_lock);
942 	value = qd->qd_change;
943 	spin_unlock(&qd_lru_lock);
944 
945 	spin_lock(&gt->gt_spin);
946 	num = gt->gt_quota_scale_num;
947 	den = gt->gt_quota_scale_den;
948 	spin_unlock(&gt->gt_spin);
949 
950 	if (value < 0)
951 		do_sync = 0;
952 	else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
953 		 (s64)be64_to_cpu(qd->qd_qb.qb_limit))
954 		do_sync = 0;
955 	else {
956 		value *= gfs2_jindex_size(sdp) * num;
957 		value = div_s64(value, den);
958 		value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
959 		if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
960 			do_sync = 0;
961 	}
962 
963 	return do_sync;
964 }
965 
966 void gfs2_quota_unlock(struct gfs2_inode *ip)
967 {
968 	struct gfs2_alloc *al = ip->i_alloc;
969 	struct gfs2_quota_data *qda[4];
970 	unsigned int count = 0;
971 	unsigned int x;
972 
973 	if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
974 		goto out;
975 
976 	for (x = 0; x < al->al_qd_num; x++) {
977 		struct gfs2_quota_data *qd;
978 		int sync;
979 
980 		qd = al->al_qd[x];
981 		sync = need_sync(qd);
982 
983 		gfs2_glock_dq_uninit(&al->al_qd_ghs[x]);
984 
985 		if (sync && qd_trylock(qd))
986 			qda[count++] = qd;
987 	}
988 
989 	if (count) {
990 		do_sync(count, qda);
991 		for (x = 0; x < count; x++)
992 			qd_unlock(qda[x]);
993 	}
994 
995 out:
996 	gfs2_quota_unhold(ip);
997 }
998 
999 #define MAX_LINE 256
1000 
1001 static int print_message(struct gfs2_quota_data *qd, char *type)
1002 {
1003 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
1004 
1005 	printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\n",
1006 	       sdp->sd_fsname, type,
1007 	       (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
1008 	       qd->qd_id);
1009 
1010 	return 0;
1011 }
1012 
1013 int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
1014 {
1015 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1016 	struct gfs2_alloc *al = ip->i_alloc;
1017 	struct gfs2_quota_data *qd;
1018 	s64 value;
1019 	unsigned int x;
1020 	int error = 0;
1021 
1022 	if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1023 		return 0;
1024 
1025         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1026                 return 0;
1027 
1028 	for (x = 0; x < al->al_qd_num; x++) {
1029 		qd = al->al_qd[x];
1030 
1031 		if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1032 		      (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
1033 			continue;
1034 
1035 		value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1036 		spin_lock(&qd_lru_lock);
1037 		value += qd->qd_change;
1038 		spin_unlock(&qd_lru_lock);
1039 
1040 		if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
1041 			print_message(qd, "exceeded");
1042 			quota_send_warning(test_bit(QDF_USER, &qd->qd_flags) ?
1043 					   USRQUOTA : GRPQUOTA, qd->qd_id,
1044 					   sdp->sd_vfs->s_dev, QUOTA_NL_BHARDWARN);
1045 
1046 			error = -EDQUOT;
1047 			break;
1048 		} else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
1049 			   (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
1050 			   time_after_eq(jiffies, qd->qd_last_warn +
1051 					 gfs2_tune_get(sdp,
1052 						gt_quota_warn_period) * HZ)) {
1053 			quota_send_warning(test_bit(QDF_USER, &qd->qd_flags) ?
1054 					   USRQUOTA : GRPQUOTA, qd->qd_id,
1055 					   sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1056 			error = print_message(qd, "warning");
1057 			qd->qd_last_warn = jiffies;
1058 		}
1059 	}
1060 
1061 	return error;
1062 }
1063 
1064 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1065 		       u32 uid, u32 gid)
1066 {
1067 	struct gfs2_alloc *al = ip->i_alloc;
1068 	struct gfs2_quota_data *qd;
1069 	unsigned int x;
1070 
1071 	if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1072 		return;
1073 	if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1074 		return;
1075 
1076 	for (x = 0; x < al->al_qd_num; x++) {
1077 		qd = al->al_qd[x];
1078 
1079 		if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1080 		    (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
1081 			do_qc(qd, change);
1082 		}
1083 	}
1084 }
1085 
1086 int gfs2_quota_sync(struct super_block *sb, int type)
1087 {
1088 	struct gfs2_sbd *sdp = sb->s_fs_info;
1089 	struct gfs2_quota_data **qda;
1090 	unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
1091 	unsigned int num_qd;
1092 	unsigned int x;
1093 	int error = 0;
1094 
1095 	sdp->sd_quota_sync_gen++;
1096 
1097 	qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1098 	if (!qda)
1099 		return -ENOMEM;
1100 
1101 	do {
1102 		num_qd = 0;
1103 
1104 		for (;;) {
1105 			error = qd_fish(sdp, qda + num_qd);
1106 			if (error || !qda[num_qd])
1107 				break;
1108 			if (++num_qd == max_qd)
1109 				break;
1110 		}
1111 
1112 		if (num_qd) {
1113 			if (!error)
1114 				error = do_sync(num_qd, qda);
1115 			if (!error)
1116 				for (x = 0; x < num_qd; x++)
1117 					qda[x]->qd_sync_gen =
1118 						sdp->sd_quota_sync_gen;
1119 
1120 			for (x = 0; x < num_qd; x++)
1121 				qd_unlock(qda[x]);
1122 		}
1123 	} while (!error && num_qd == max_qd);
1124 
1125 	kfree(qda);
1126 
1127 	return error;
1128 }
1129 
1130 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
1131 {
1132 	struct gfs2_quota_data *qd;
1133 	struct gfs2_holder q_gh;
1134 	int error;
1135 
1136 	error = qd_get(sdp, user, id, &qd);
1137 	if (error)
1138 		return error;
1139 
1140 	error = do_glock(qd, FORCE, &q_gh);
1141 	if (!error)
1142 		gfs2_glock_dq_uninit(&q_gh);
1143 
1144 	qd_put(qd);
1145 	return error;
1146 }
1147 
1148 static void gfs2_quota_change_in(struct gfs2_quota_change_host *qc, const void *buf)
1149 {
1150 	const struct gfs2_quota_change *str = buf;
1151 
1152 	qc->qc_change = be64_to_cpu(str->qc_change);
1153 	qc->qc_flags = be32_to_cpu(str->qc_flags);
1154 	qc->qc_id = be32_to_cpu(str->qc_id);
1155 }
1156 
1157 int gfs2_quota_init(struct gfs2_sbd *sdp)
1158 {
1159 	struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1160 	unsigned int blocks = ip->i_disksize >> sdp->sd_sb.sb_bsize_shift;
1161 	unsigned int x, slot = 0;
1162 	unsigned int found = 0;
1163 	u64 dblock;
1164 	u32 extlen = 0;
1165 	int error;
1166 
1167 	if (!ip->i_disksize || ip->i_disksize > (64 << 20) ||
1168 	    ip->i_disksize & (sdp->sd_sb.sb_bsize - 1)) {
1169 		gfs2_consist_inode(ip);
1170 		return -EIO;
1171 	}
1172 	sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1173 	sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1174 
1175 	error = -ENOMEM;
1176 
1177 	sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1178 				       sizeof(unsigned char *), GFP_NOFS);
1179 	if (!sdp->sd_quota_bitmap)
1180 		return error;
1181 
1182 	for (x = 0; x < sdp->sd_quota_chunks; x++) {
1183 		sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_NOFS);
1184 		if (!sdp->sd_quota_bitmap[x])
1185 			goto fail;
1186 	}
1187 
1188 	for (x = 0; x < blocks; x++) {
1189 		struct buffer_head *bh;
1190 		unsigned int y;
1191 
1192 		if (!extlen) {
1193 			int new = 0;
1194 			error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1195 			if (error)
1196 				goto fail;
1197 		}
1198 		error = -EIO;
1199 		bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1200 		if (!bh)
1201 			goto fail;
1202 		if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1203 			brelse(bh);
1204 			goto fail;
1205 		}
1206 
1207 		for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1208 		     y++, slot++) {
1209 			struct gfs2_quota_change_host qc;
1210 			struct gfs2_quota_data *qd;
1211 
1212 			gfs2_quota_change_in(&qc, bh->b_data +
1213 					  sizeof(struct gfs2_meta_header) +
1214 					  y * sizeof(struct gfs2_quota_change));
1215 			if (!qc.qc_change)
1216 				continue;
1217 
1218 			error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1219 					 qc.qc_id, &qd);
1220 			if (error) {
1221 				brelse(bh);
1222 				goto fail;
1223 			}
1224 
1225 			set_bit(QDF_CHANGE, &qd->qd_flags);
1226 			qd->qd_change = qc.qc_change;
1227 			qd->qd_slot = slot;
1228 			qd->qd_slot_count = 1;
1229 
1230 			spin_lock(&qd_lru_lock);
1231 			gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1232 			list_add(&qd->qd_list, &sdp->sd_quota_list);
1233 			atomic_inc(&sdp->sd_quota_count);
1234 			spin_unlock(&qd_lru_lock);
1235 
1236 			found++;
1237 		}
1238 
1239 		brelse(bh);
1240 		dblock++;
1241 		extlen--;
1242 	}
1243 
1244 	if (found)
1245 		fs_info(sdp, "found %u quota changes\n", found);
1246 
1247 	return 0;
1248 
1249 fail:
1250 	gfs2_quota_cleanup(sdp);
1251 	return error;
1252 }
1253 
1254 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1255 {
1256 	struct list_head *head = &sdp->sd_quota_list;
1257 	struct gfs2_quota_data *qd;
1258 	unsigned int x;
1259 
1260 	spin_lock(&qd_lru_lock);
1261 	while (!list_empty(head)) {
1262 		qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1263 
1264 		if (atomic_read(&qd->qd_count) > 1 ||
1265 		    (atomic_read(&qd->qd_count) &&
1266 		     !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1267 			list_move(&qd->qd_list, head);
1268 			spin_unlock(&qd_lru_lock);
1269 			schedule();
1270 			spin_lock(&qd_lru_lock);
1271 			continue;
1272 		}
1273 
1274 		list_del(&qd->qd_list);
1275 		/* Also remove if this qd exists in the reclaim list */
1276 		if (!list_empty(&qd->qd_reclaim)) {
1277 			list_del_init(&qd->qd_reclaim);
1278 			atomic_dec(&qd_lru_count);
1279 		}
1280 		atomic_dec(&sdp->sd_quota_count);
1281 		spin_unlock(&qd_lru_lock);
1282 
1283 		if (!atomic_read(&qd->qd_count)) {
1284 			gfs2_assert_warn(sdp, !qd->qd_change);
1285 			gfs2_assert_warn(sdp, !qd->qd_slot_count);
1286 		} else
1287 			gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1288 		gfs2_assert_warn(sdp, !qd->qd_bh_count);
1289 
1290 		gfs2_glock_put(qd->qd_gl);
1291 		kmem_cache_free(gfs2_quotad_cachep, qd);
1292 
1293 		spin_lock(&qd_lru_lock);
1294 	}
1295 	spin_unlock(&qd_lru_lock);
1296 
1297 	gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1298 
1299 	if (sdp->sd_quota_bitmap) {
1300 		for (x = 0; x < sdp->sd_quota_chunks; x++)
1301 			kfree(sdp->sd_quota_bitmap[x]);
1302 		kfree(sdp->sd_quota_bitmap);
1303 	}
1304 }
1305 
1306 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1307 {
1308 	if (error == 0 || error == -EROFS)
1309 		return;
1310 	if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1311 		fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1312 }
1313 
1314 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1315 			       int (*fxn)(struct super_block *sb, int type),
1316 			       unsigned long t, unsigned long *timeo,
1317 			       unsigned int *new_timeo)
1318 {
1319 	if (t >= *timeo) {
1320 		int error = fxn(sdp->sd_vfs, 0);
1321 		quotad_error(sdp, msg, error);
1322 		*timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1323 	} else {
1324 		*timeo -= t;
1325 	}
1326 }
1327 
1328 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1329 {
1330 	struct gfs2_inode *ip;
1331 
1332 	while(1) {
1333 		ip = NULL;
1334 		spin_lock(&sdp->sd_trunc_lock);
1335 		if (!list_empty(&sdp->sd_trunc_list)) {
1336 			ip = list_entry(sdp->sd_trunc_list.next,
1337 					struct gfs2_inode, i_trunc_list);
1338 			list_del_init(&ip->i_trunc_list);
1339 		}
1340 		spin_unlock(&sdp->sd_trunc_lock);
1341 		if (ip == NULL)
1342 			return;
1343 		gfs2_glock_finish_truncate(ip);
1344 	}
1345 }
1346 
1347 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1348 	if (!sdp->sd_statfs_force_sync) {
1349 		sdp->sd_statfs_force_sync = 1;
1350 		wake_up(&sdp->sd_quota_wait);
1351 	}
1352 }
1353 
1354 
1355 /**
1356  * gfs2_quotad - Write cached quota changes into the quota file
1357  * @sdp: Pointer to GFS2 superblock
1358  *
1359  */
1360 
1361 int gfs2_quotad(void *data)
1362 {
1363 	struct gfs2_sbd *sdp = data;
1364 	struct gfs2_tune *tune = &sdp->sd_tune;
1365 	unsigned long statfs_timeo = 0;
1366 	unsigned long quotad_timeo = 0;
1367 	unsigned long t = 0;
1368 	DEFINE_WAIT(wait);
1369 	int empty;
1370 
1371 	while (!kthread_should_stop()) {
1372 
1373 		/* Update the master statfs file */
1374 		if (sdp->sd_statfs_force_sync) {
1375 			int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1376 			quotad_error(sdp, "statfs", error);
1377 			statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1378 		}
1379 		else
1380 			quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1381 				   	   &statfs_timeo,
1382 					   &tune->gt_statfs_quantum);
1383 
1384 		/* Update quota file */
1385 		quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
1386 				   &quotad_timeo, &tune->gt_quota_quantum);
1387 
1388 		/* Check for & recover partially truncated inodes */
1389 		quotad_check_trunc_list(sdp);
1390 
1391 		if (freezing(current))
1392 			refrigerator();
1393 		t = min(quotad_timeo, statfs_timeo);
1394 
1395 		prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1396 		spin_lock(&sdp->sd_trunc_lock);
1397 		empty = list_empty(&sdp->sd_trunc_list);
1398 		spin_unlock(&sdp->sd_trunc_lock);
1399 		if (empty && !sdp->sd_statfs_force_sync)
1400 			t -= schedule_timeout(t);
1401 		else
1402 			t = 0;
1403 		finish_wait(&sdp->sd_quota_wait, &wait);
1404 	}
1405 
1406 	return 0;
1407 }
1408 
1409 static int gfs2_quota_get_xstate(struct super_block *sb,
1410 				 struct fs_quota_stat *fqs)
1411 {
1412 	struct gfs2_sbd *sdp = sb->s_fs_info;
1413 
1414 	memset(fqs, 0, sizeof(struct fs_quota_stat));
1415 	fqs->qs_version = FS_QSTAT_VERSION;
1416 	if (sdp->sd_args.ar_quota == GFS2_QUOTA_ON)
1417 		fqs->qs_flags = (XFS_QUOTA_UDQ_ENFD | XFS_QUOTA_GDQ_ENFD);
1418 	else if (sdp->sd_args.ar_quota == GFS2_QUOTA_ACCOUNT)
1419 		fqs->qs_flags = (XFS_QUOTA_UDQ_ACCT | XFS_QUOTA_GDQ_ACCT);
1420 	if (sdp->sd_quota_inode) {
1421 		fqs->qs_uquota.qfs_ino = GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1422 		fqs->qs_uquota.qfs_nblks = sdp->sd_quota_inode->i_blocks;
1423 	}
1424 	fqs->qs_uquota.qfs_nextents = 1; /* unsupported */
1425 	fqs->qs_gquota = fqs->qs_uquota; /* its the same inode in both cases */
1426 	fqs->qs_incoredqs = atomic_read(&qd_lru_count);
1427 	return 0;
1428 }
1429 
1430 static int gfs2_xquota_get(struct super_block *sb, int type, qid_t id,
1431 			   struct fs_disk_quota *fdq)
1432 {
1433 	struct gfs2_sbd *sdp = sb->s_fs_info;
1434 	struct gfs2_quota_lvb *qlvb;
1435 	struct gfs2_quota_data *qd;
1436 	struct gfs2_holder q_gh;
1437 	int error;
1438 
1439 	memset(fdq, 0, sizeof(struct fs_disk_quota));
1440 
1441 	if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1442 		return -ESRCH; /* Crazy XFS error code */
1443 
1444 	if (type == USRQUOTA)
1445 		type = QUOTA_USER;
1446 	else if (type == GRPQUOTA)
1447 		type = QUOTA_GROUP;
1448 	else
1449 		return -EINVAL;
1450 
1451 	error = qd_get(sdp, type, id, &qd);
1452 	if (error)
1453 		return error;
1454 	error = do_glock(qd, FORCE, &q_gh);
1455 	if (error)
1456 		goto out;
1457 
1458 	qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
1459 	fdq->d_version = FS_DQUOT_VERSION;
1460 	fdq->d_flags = (type == QUOTA_USER) ? XFS_USER_QUOTA : XFS_GROUP_QUOTA;
1461 	fdq->d_id = id;
1462 	fdq->d_blk_hardlimit = be64_to_cpu(qlvb->qb_limit);
1463 	fdq->d_blk_softlimit = be64_to_cpu(qlvb->qb_warn);
1464 	fdq->d_bcount = be64_to_cpu(qlvb->qb_value);
1465 
1466 	gfs2_glock_dq_uninit(&q_gh);
1467 out:
1468 	qd_put(qd);
1469 	return error;
1470 }
1471 
1472 /* GFS2 only supports a subset of the XFS fields */
1473 #define GFS2_FIELDMASK (FS_DQ_BSOFT|FS_DQ_BHARD)
1474 
1475 static int gfs2_xquota_set(struct super_block *sb, int type, qid_t id,
1476 			   struct fs_disk_quota *fdq)
1477 {
1478 	struct gfs2_sbd *sdp = sb->s_fs_info;
1479 	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1480 	struct gfs2_quota_data *qd;
1481 	struct gfs2_holder q_gh, i_gh;
1482 	unsigned int data_blocks, ind_blocks;
1483 	unsigned int blocks = 0;
1484 	int alloc_required;
1485 	struct gfs2_alloc *al;
1486 	loff_t offset;
1487 	int error;
1488 
1489 	if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1490 		return -ESRCH; /* Crazy XFS error code */
1491 
1492 	switch(type) {
1493 	case USRQUOTA:
1494 		type = QUOTA_USER;
1495 		if (fdq->d_flags != XFS_USER_QUOTA)
1496 			return -EINVAL;
1497 		break;
1498 	case GRPQUOTA:
1499 		type = QUOTA_GROUP;
1500 		if (fdq->d_flags != XFS_GROUP_QUOTA)
1501 			return -EINVAL;
1502 		break;
1503 	default:
1504 		return -EINVAL;
1505 	}
1506 
1507 	if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1508 		return -EINVAL;
1509 	if (fdq->d_id != id)
1510 		return -EINVAL;
1511 
1512 	error = qd_get(sdp, type, id, &qd);
1513 	if (error)
1514 		return error;
1515 
1516 	mutex_lock(&ip->i_inode.i_mutex);
1517 	error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1518 	if (error)
1519 		goto out_put;
1520 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1521 	if (error)
1522 		goto out_q;
1523 
1524 	/* Check for existing entry, if none then alloc new blocks */
1525 	error = update_qd(sdp, qd);
1526 	if (error)
1527 		goto out_i;
1528 
1529 	/* If nothing has changed, this is a no-op */
1530 	if ((fdq->d_fieldmask & FS_DQ_BSOFT) &&
1531 	    (fdq->d_blk_softlimit == be64_to_cpu(qd->qd_qb.qb_warn)))
1532 		fdq->d_fieldmask ^= FS_DQ_BSOFT;
1533 	if ((fdq->d_fieldmask & FS_DQ_BHARD) &&
1534 	    (fdq->d_blk_hardlimit == be64_to_cpu(qd->qd_qb.qb_limit)))
1535 		fdq->d_fieldmask ^= FS_DQ_BHARD;
1536 	if (fdq->d_fieldmask == 0)
1537 		goto out_i;
1538 
1539 	offset = qd2offset(qd);
1540 	error = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota),
1541 					  &alloc_required);
1542 	if (error)
1543 		goto out_i;
1544 	if (alloc_required) {
1545 		al = gfs2_alloc_get(ip);
1546 		if (al == NULL)
1547 			goto out_i;
1548 		gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1549 				       &data_blocks, &ind_blocks);
1550 		blocks = al->al_requested = 1 + data_blocks + ind_blocks;
1551 		error = gfs2_inplace_reserve(ip);
1552 		if (error)
1553 			goto out_alloc;
1554 	}
1555 
1556 	error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 1, 0);
1557 	if (error)
1558 		goto out_release;
1559 
1560 	/* Apply changes */
1561 	error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1562 
1563 	gfs2_trans_end(sdp);
1564 out_release:
1565 	if (alloc_required) {
1566 		gfs2_inplace_release(ip);
1567 out_alloc:
1568 		gfs2_alloc_put(ip);
1569 	}
1570 out_i:
1571 	gfs2_glock_dq_uninit(&i_gh);
1572 out_q:
1573 	gfs2_glock_dq_uninit(&q_gh);
1574 out_put:
1575 	mutex_unlock(&ip->i_inode.i_mutex);
1576 	qd_put(qd);
1577 	return error;
1578 }
1579 
1580 const struct quotactl_ops gfs2_quotactl_ops = {
1581 	.quota_sync     = gfs2_quota_sync,
1582 	.get_xstate     = gfs2_quota_get_xstate,
1583 	.get_xquota	= gfs2_xquota_get,
1584 	.set_xquota	= gfs2_xquota_set,
1585 };
1586 
1587