xref: /openbmc/linux/fs/gfs2/quota.c (revision 95e9fd10)
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_quota_data **qd;
498 	int error;
499 
500 	if (ip->i_res == NULL)
501 		gfs2_rs_alloc(ip);
502 
503 	qd = ip->i_res->rs_qa_qd;
504 
505 	if (gfs2_assert_warn(sdp, !ip->i_res->rs_qa_qd_num) ||
506 	    gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
507 		return -EIO;
508 
509 	if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
510 		return 0;
511 
512 	error = qdsb_get(sdp, QUOTA_USER, ip->i_inode.i_uid, qd);
513 	if (error)
514 		goto out;
515 	ip->i_res->rs_qa_qd_num++;
516 	qd++;
517 
518 	error = qdsb_get(sdp, QUOTA_GROUP, ip->i_inode.i_gid, qd);
519 	if (error)
520 		goto out;
521 	ip->i_res->rs_qa_qd_num++;
522 	qd++;
523 
524 	if (uid != NO_QUOTA_CHANGE && uid != ip->i_inode.i_uid) {
525 		error = qdsb_get(sdp, QUOTA_USER, uid, qd);
526 		if (error)
527 			goto out;
528 		ip->i_res->rs_qa_qd_num++;
529 		qd++;
530 	}
531 
532 	if (gid != NO_QUOTA_CHANGE && gid != ip->i_inode.i_gid) {
533 		error = qdsb_get(sdp, QUOTA_GROUP, gid, qd);
534 		if (error)
535 			goto out;
536 		ip->i_res->rs_qa_qd_num++;
537 		qd++;
538 	}
539 
540 out:
541 	if (error)
542 		gfs2_quota_unhold(ip);
543 	return error;
544 }
545 
546 void gfs2_quota_unhold(struct gfs2_inode *ip)
547 {
548 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
549 	unsigned int x;
550 
551 	if (ip->i_res == NULL)
552 		return;
553 	gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
554 
555 	for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
556 		qdsb_put(ip->i_res->rs_qa_qd[x]);
557 		ip->i_res->rs_qa_qd[x] = NULL;
558 	}
559 	ip->i_res->rs_qa_qd_num = 0;
560 }
561 
562 static int sort_qd(const void *a, const void *b)
563 {
564 	const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
565 	const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
566 
567 	if (!test_bit(QDF_USER, &qd_a->qd_flags) !=
568 	    !test_bit(QDF_USER, &qd_b->qd_flags)) {
569 		if (test_bit(QDF_USER, &qd_a->qd_flags))
570 			return -1;
571 		else
572 			return 1;
573 	}
574 	if (qd_a->qd_id < qd_b->qd_id)
575 		return -1;
576 	if (qd_a->qd_id > qd_b->qd_id)
577 		return 1;
578 
579 	return 0;
580 }
581 
582 static void do_qc(struct gfs2_quota_data *qd, s64 change)
583 {
584 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
585 	struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
586 	struct gfs2_quota_change *qc = qd->qd_bh_qc;
587 	s64 x;
588 
589 	mutex_lock(&sdp->sd_quota_mutex);
590 	gfs2_trans_add_bh(ip->i_gl, qd->qd_bh, 1);
591 
592 	if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
593 		qc->qc_change = 0;
594 		qc->qc_flags = 0;
595 		if (test_bit(QDF_USER, &qd->qd_flags))
596 			qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
597 		qc->qc_id = cpu_to_be32(qd->qd_id);
598 	}
599 
600 	x = be64_to_cpu(qc->qc_change) + change;
601 	qc->qc_change = cpu_to_be64(x);
602 
603 	spin_lock(&qd_lru_lock);
604 	qd->qd_change = x;
605 	spin_unlock(&qd_lru_lock);
606 
607 	if (!x) {
608 		gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
609 		clear_bit(QDF_CHANGE, &qd->qd_flags);
610 		qc->qc_flags = 0;
611 		qc->qc_id = 0;
612 		slot_put(qd);
613 		qd_put(qd);
614 	} else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
615 		qd_hold(qd);
616 		slot_hold(qd);
617 	}
618 
619 	mutex_unlock(&sdp->sd_quota_mutex);
620 }
621 
622 /**
623  * gfs2_adjust_quota - adjust record of current block usage
624  * @ip: The quota inode
625  * @loc: Offset of the entry in the quota file
626  * @change: The amount of usage change to record
627  * @qd: The quota data
628  * @fdq: The updated limits to record
629  *
630  * This function was mostly borrowed from gfs2_block_truncate_page which was
631  * in turn mostly borrowed from ext3
632  *
633  * Returns: 0 or -ve on error
634  */
635 
636 static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
637 			     s64 change, struct gfs2_quota_data *qd,
638 			     struct fs_disk_quota *fdq)
639 {
640 	struct inode *inode = &ip->i_inode;
641 	struct gfs2_sbd *sdp = GFS2_SB(inode);
642 	struct address_space *mapping = inode->i_mapping;
643 	unsigned long index = loc >> PAGE_CACHE_SHIFT;
644 	unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
645 	unsigned blocksize, iblock, pos;
646 	struct buffer_head *bh;
647 	struct page *page;
648 	void *kaddr, *ptr;
649 	struct gfs2_quota q, *qp;
650 	int err, nbytes;
651 	u64 size;
652 
653 	if (gfs2_is_stuffed(ip)) {
654 		err = gfs2_unstuff_dinode(ip, NULL);
655 		if (err)
656 			return err;
657 	}
658 
659 	memset(&q, 0, sizeof(struct gfs2_quota));
660 	err = gfs2_internal_read(ip, (char *)&q, &loc, sizeof(q));
661 	if (err < 0)
662 		return err;
663 
664 	err = -EIO;
665 	qp = &q;
666 	qp->qu_value = be64_to_cpu(qp->qu_value);
667 	qp->qu_value += change;
668 	qp->qu_value = cpu_to_be64(qp->qu_value);
669 	qd->qd_qb.qb_value = qp->qu_value;
670 	if (fdq) {
671 		if (fdq->d_fieldmask & FS_DQ_BSOFT) {
672 			qp->qu_warn = cpu_to_be64(fdq->d_blk_softlimit >> sdp->sd_fsb2bb_shift);
673 			qd->qd_qb.qb_warn = qp->qu_warn;
674 		}
675 		if (fdq->d_fieldmask & FS_DQ_BHARD) {
676 			qp->qu_limit = cpu_to_be64(fdq->d_blk_hardlimit >> sdp->sd_fsb2bb_shift);
677 			qd->qd_qb.qb_limit = qp->qu_limit;
678 		}
679 		if (fdq->d_fieldmask & FS_DQ_BCOUNT) {
680 			qp->qu_value = cpu_to_be64(fdq->d_bcount >> sdp->sd_fsb2bb_shift);
681 			qd->qd_qb.qb_value = qp->qu_value;
682 		}
683 	}
684 
685 	/* Write the quota into the quota file on disk */
686 	ptr = qp;
687 	nbytes = sizeof(struct gfs2_quota);
688 get_a_page:
689 	page = find_or_create_page(mapping, index, GFP_NOFS);
690 	if (!page)
691 		return -ENOMEM;
692 
693 	blocksize = inode->i_sb->s_blocksize;
694 	iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
695 
696 	if (!page_has_buffers(page))
697 		create_empty_buffers(page, blocksize, 0);
698 
699 	bh = page_buffers(page);
700 	pos = blocksize;
701 	while (offset >= pos) {
702 		bh = bh->b_this_page;
703 		iblock++;
704 		pos += blocksize;
705 	}
706 
707 	if (!buffer_mapped(bh)) {
708 		gfs2_block_map(inode, iblock, bh, 1);
709 		if (!buffer_mapped(bh))
710 			goto unlock_out;
711 		/* If it's a newly allocated disk block for quota, zero it */
712 		if (buffer_new(bh))
713 			zero_user(page, pos - blocksize, bh->b_size);
714 	}
715 
716 	if (PageUptodate(page))
717 		set_buffer_uptodate(bh);
718 
719 	if (!buffer_uptodate(bh)) {
720 		ll_rw_block(READ | REQ_META, 1, &bh);
721 		wait_on_buffer(bh);
722 		if (!buffer_uptodate(bh))
723 			goto unlock_out;
724 	}
725 
726 	gfs2_trans_add_bh(ip->i_gl, bh, 0);
727 
728 	kaddr = kmap_atomic(page);
729 	if (offset + sizeof(struct gfs2_quota) > PAGE_CACHE_SIZE)
730 		nbytes = PAGE_CACHE_SIZE - offset;
731 	memcpy(kaddr + offset, ptr, nbytes);
732 	flush_dcache_page(page);
733 	kunmap_atomic(kaddr);
734 	unlock_page(page);
735 	page_cache_release(page);
736 
737 	/* If quota straddles page boundary, we need to update the rest of the
738 	 * quota at the beginning of the next page */
739 	if ((offset + sizeof(struct gfs2_quota)) > PAGE_CACHE_SIZE) {
740 		ptr = ptr + nbytes;
741 		nbytes = sizeof(struct gfs2_quota) - nbytes;
742 		offset = 0;
743 		index++;
744 		goto get_a_page;
745 	}
746 
747 	size = loc + sizeof(struct gfs2_quota);
748 	if (size > inode->i_size)
749 		i_size_write(inode, size);
750 	inode->i_mtime = inode->i_atime = CURRENT_TIME;
751 	mark_inode_dirty(inode);
752 	return 0;
753 
754 unlock_out:
755 	unlock_page(page);
756 	page_cache_release(page);
757 	return err;
758 }
759 
760 static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
761 {
762 	struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
763 	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
764 	unsigned int data_blocks, ind_blocks;
765 	struct gfs2_holder *ghs, i_gh;
766 	unsigned int qx, x;
767 	struct gfs2_quota_data *qd;
768 	loff_t offset;
769 	unsigned int nalloc = 0, blocks;
770 	int error;
771 
772 	error = gfs2_rs_alloc(ip);
773 	if (error)
774 		return error;
775 
776 	gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
777 			      &data_blocks, &ind_blocks);
778 
779 	ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
780 	if (!ghs)
781 		return -ENOMEM;
782 
783 	sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
784 	mutex_lock_nested(&ip->i_inode.i_mutex, I_MUTEX_QUOTA);
785 	for (qx = 0; qx < num_qd; qx++) {
786 		error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
787 					   GL_NOCACHE, &ghs[qx]);
788 		if (error)
789 			goto out;
790 	}
791 
792 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
793 	if (error)
794 		goto out;
795 
796 	for (x = 0; x < num_qd; x++) {
797 		offset = qd2offset(qda[x]);
798 		if (gfs2_write_alloc_required(ip, offset,
799 					      sizeof(struct gfs2_quota)))
800 			nalloc++;
801 	}
802 
803 	/*
804 	 * 1 blk for unstuffing inode if stuffed. We add this extra
805 	 * block to the reservation unconditionally. If the inode
806 	 * doesn't need unstuffing, the block will be released to the
807 	 * rgrp since it won't be allocated during the transaction
808 	 */
809 	/* +3 in the end for unstuffing block, inode size update block
810 	 * and another block in case quota straddles page boundary and
811 	 * two blocks need to be updated instead of 1 */
812 	blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
813 
814 	error = gfs2_inplace_reserve(ip, 1 +
815 				     (nalloc * (data_blocks + ind_blocks)));
816 	if (error)
817 		goto out_alloc;
818 
819 	if (nalloc)
820 		blocks += gfs2_rg_blocks(ip) + nalloc * ind_blocks + RES_STATFS;
821 
822 	error = gfs2_trans_begin(sdp, blocks, 0);
823 	if (error)
824 		goto out_ipres;
825 
826 	for (x = 0; x < num_qd; x++) {
827 		qd = qda[x];
828 		offset = qd2offset(qd);
829 		error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
830 		if (error)
831 			goto out_end_trans;
832 
833 		do_qc(qd, -qd->qd_change_sync);
834 		set_bit(QDF_REFRESH, &qd->qd_flags);
835 	}
836 
837 	error = 0;
838 
839 out_end_trans:
840 	gfs2_trans_end(sdp);
841 out_ipres:
842 	gfs2_inplace_release(ip);
843 out_alloc:
844 	gfs2_glock_dq_uninit(&i_gh);
845 out:
846 	while (qx--)
847 		gfs2_glock_dq_uninit(&ghs[qx]);
848 	mutex_unlock(&ip->i_inode.i_mutex);
849 	kfree(ghs);
850 	gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl);
851 	return error;
852 }
853 
854 static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
855 {
856 	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
857 	struct gfs2_quota q;
858 	struct gfs2_quota_lvb *qlvb;
859 	loff_t pos;
860 	int error;
861 
862 	memset(&q, 0, sizeof(struct gfs2_quota));
863 	pos = qd2offset(qd);
864 	error = gfs2_internal_read(ip, (char *)&q, &pos, sizeof(q));
865 	if (error < 0)
866 		return error;
867 
868 	qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
869 	qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
870 	qlvb->__pad = 0;
871 	qlvb->qb_limit = q.qu_limit;
872 	qlvb->qb_warn = q.qu_warn;
873 	qlvb->qb_value = q.qu_value;
874 	qd->qd_qb = *qlvb;
875 
876 	return 0;
877 }
878 
879 static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
880 		    struct gfs2_holder *q_gh)
881 {
882 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
883 	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
884 	struct gfs2_holder i_gh;
885 	int error;
886 
887 restart:
888 	error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
889 	if (error)
890 		return error;
891 
892 	qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
893 
894 	if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
895 		gfs2_glock_dq_uninit(q_gh);
896 		error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
897 					   GL_NOCACHE, q_gh);
898 		if (error)
899 			return error;
900 
901 		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
902 		if (error)
903 			goto fail;
904 
905 		error = update_qd(sdp, qd);
906 		if (error)
907 			goto fail_gunlock;
908 
909 		gfs2_glock_dq_uninit(&i_gh);
910 		gfs2_glock_dq_uninit(q_gh);
911 		force_refresh = 0;
912 		goto restart;
913 	}
914 
915 	return 0;
916 
917 fail_gunlock:
918 	gfs2_glock_dq_uninit(&i_gh);
919 fail:
920 	gfs2_glock_dq_uninit(q_gh);
921 	return error;
922 }
923 
924 int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
925 {
926 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
927 	struct gfs2_quota_data *qd;
928 	unsigned int x;
929 	int error = 0;
930 
931 	error = gfs2_quota_hold(ip, uid, gid);
932 	if (error)
933 		return error;
934 
935 	if (capable(CAP_SYS_RESOURCE) ||
936 	    sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
937 		return 0;
938 
939 	sort(ip->i_res->rs_qa_qd, ip->i_res->rs_qa_qd_num,
940 	     sizeof(struct gfs2_quota_data *), sort_qd, NULL);
941 
942 	for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
943 		int force = NO_FORCE;
944 		qd = ip->i_res->rs_qa_qd[x];
945 		if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
946 			force = FORCE;
947 		error = do_glock(qd, force, &ip->i_res->rs_qa_qd_ghs[x]);
948 		if (error)
949 			break;
950 	}
951 
952 	if (!error)
953 		set_bit(GIF_QD_LOCKED, &ip->i_flags);
954 	else {
955 		while (x--)
956 			gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
957 		gfs2_quota_unhold(ip);
958 	}
959 
960 	return error;
961 }
962 
963 static int need_sync(struct gfs2_quota_data *qd)
964 {
965 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
966 	struct gfs2_tune *gt = &sdp->sd_tune;
967 	s64 value;
968 	unsigned int num, den;
969 	int do_sync = 1;
970 
971 	if (!qd->qd_qb.qb_limit)
972 		return 0;
973 
974 	spin_lock(&qd_lru_lock);
975 	value = qd->qd_change;
976 	spin_unlock(&qd_lru_lock);
977 
978 	spin_lock(&gt->gt_spin);
979 	num = gt->gt_quota_scale_num;
980 	den = gt->gt_quota_scale_den;
981 	spin_unlock(&gt->gt_spin);
982 
983 	if (value < 0)
984 		do_sync = 0;
985 	else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
986 		 (s64)be64_to_cpu(qd->qd_qb.qb_limit))
987 		do_sync = 0;
988 	else {
989 		value *= gfs2_jindex_size(sdp) * num;
990 		value = div_s64(value, den);
991 		value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
992 		if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
993 			do_sync = 0;
994 	}
995 
996 	return do_sync;
997 }
998 
999 void gfs2_quota_unlock(struct gfs2_inode *ip)
1000 {
1001 	struct gfs2_quota_data *qda[4];
1002 	unsigned int count = 0;
1003 	unsigned int x;
1004 
1005 	if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1006 		goto out;
1007 
1008 	for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1009 		struct gfs2_quota_data *qd;
1010 		int sync;
1011 
1012 		qd = ip->i_res->rs_qa_qd[x];
1013 		sync = need_sync(qd);
1014 
1015 		gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
1016 
1017 		if (sync && qd_trylock(qd))
1018 			qda[count++] = qd;
1019 	}
1020 
1021 	if (count) {
1022 		do_sync(count, qda);
1023 		for (x = 0; x < count; x++)
1024 			qd_unlock(qda[x]);
1025 	}
1026 
1027 out:
1028 	gfs2_quota_unhold(ip);
1029 }
1030 
1031 #define MAX_LINE 256
1032 
1033 static int print_message(struct gfs2_quota_data *qd, char *type)
1034 {
1035 	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
1036 
1037 	printk(KERN_INFO "GFS2: fsid=%s: quota %s for %s %u\n",
1038 	       sdp->sd_fsname, type,
1039 	       (test_bit(QDF_USER, &qd->qd_flags)) ? "user" : "group",
1040 	       qd->qd_id);
1041 
1042 	return 0;
1043 }
1044 
1045 int gfs2_quota_check(struct gfs2_inode *ip, u32 uid, u32 gid)
1046 {
1047 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1048 	struct gfs2_quota_data *qd;
1049 	s64 value;
1050 	unsigned int x;
1051 	int error = 0;
1052 
1053 	if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1054 		return 0;
1055 
1056         if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1057                 return 0;
1058 
1059 	for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1060 		qd = ip->i_res->rs_qa_qd[x];
1061 
1062 		if (!((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1063 		      (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))))
1064 			continue;
1065 
1066 		value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1067 		spin_lock(&qd_lru_lock);
1068 		value += qd->qd_change;
1069 		spin_unlock(&qd_lru_lock);
1070 
1071 		if (be64_to_cpu(qd->qd_qb.qb_limit) && (s64)be64_to_cpu(qd->qd_qb.qb_limit) < value) {
1072 			print_message(qd, "exceeded");
1073 			quota_send_warning(test_bit(QDF_USER, &qd->qd_flags) ?
1074 					   USRQUOTA : GRPQUOTA, qd->qd_id,
1075 					   sdp->sd_vfs->s_dev, QUOTA_NL_BHARDWARN);
1076 
1077 			error = -EDQUOT;
1078 			break;
1079 		} else if (be64_to_cpu(qd->qd_qb.qb_warn) &&
1080 			   (s64)be64_to_cpu(qd->qd_qb.qb_warn) < value &&
1081 			   time_after_eq(jiffies, qd->qd_last_warn +
1082 					 gfs2_tune_get(sdp,
1083 						gt_quota_warn_period) * HZ)) {
1084 			quota_send_warning(test_bit(QDF_USER, &qd->qd_flags) ?
1085 					   USRQUOTA : GRPQUOTA, qd->qd_id,
1086 					   sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1087 			error = print_message(qd, "warning");
1088 			qd->qd_last_warn = jiffies;
1089 		}
1090 	}
1091 
1092 	return error;
1093 }
1094 
1095 void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1096 		       u32 uid, u32 gid)
1097 {
1098 	struct gfs2_quota_data *qd;
1099 	unsigned int x;
1100 
1101 	if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1102 		return;
1103 	if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1104 		return;
1105 
1106 	for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1107 		qd = ip->i_res->rs_qa_qd[x];
1108 
1109 		if ((qd->qd_id == uid && test_bit(QDF_USER, &qd->qd_flags)) ||
1110 		    (qd->qd_id == gid && !test_bit(QDF_USER, &qd->qd_flags))) {
1111 			do_qc(qd, change);
1112 		}
1113 	}
1114 }
1115 
1116 int gfs2_quota_sync(struct super_block *sb, int type)
1117 {
1118 	struct gfs2_sbd *sdp = sb->s_fs_info;
1119 	struct gfs2_quota_data **qda;
1120 	unsigned int max_qd = gfs2_tune_get(sdp, gt_quota_simul_sync);
1121 	unsigned int num_qd;
1122 	unsigned int x;
1123 	int error = 0;
1124 
1125 	sdp->sd_quota_sync_gen++;
1126 
1127 	qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1128 	if (!qda)
1129 		return -ENOMEM;
1130 
1131 	do {
1132 		num_qd = 0;
1133 
1134 		for (;;) {
1135 			error = qd_fish(sdp, qda + num_qd);
1136 			if (error || !qda[num_qd])
1137 				break;
1138 			if (++num_qd == max_qd)
1139 				break;
1140 		}
1141 
1142 		if (num_qd) {
1143 			if (!error)
1144 				error = do_sync(num_qd, qda);
1145 			if (!error)
1146 				for (x = 0; x < num_qd; x++)
1147 					qda[x]->qd_sync_gen =
1148 						sdp->sd_quota_sync_gen;
1149 
1150 			for (x = 0; x < num_qd; x++)
1151 				qd_unlock(qda[x]);
1152 		}
1153 	} while (!error && num_qd == max_qd);
1154 
1155 	kfree(qda);
1156 
1157 	return error;
1158 }
1159 
1160 static int gfs2_quota_sync_timeo(struct super_block *sb, int type)
1161 {
1162 	return gfs2_quota_sync(sb, type);
1163 }
1164 
1165 int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id)
1166 {
1167 	struct gfs2_quota_data *qd;
1168 	struct gfs2_holder q_gh;
1169 	int error;
1170 
1171 	error = qd_get(sdp, user, id, &qd);
1172 	if (error)
1173 		return error;
1174 
1175 	error = do_glock(qd, FORCE, &q_gh);
1176 	if (!error)
1177 		gfs2_glock_dq_uninit(&q_gh);
1178 
1179 	qd_put(qd);
1180 	return error;
1181 }
1182 
1183 static void gfs2_quota_change_in(struct gfs2_quota_change_host *qc, const void *buf)
1184 {
1185 	const struct gfs2_quota_change *str = buf;
1186 
1187 	qc->qc_change = be64_to_cpu(str->qc_change);
1188 	qc->qc_flags = be32_to_cpu(str->qc_flags);
1189 	qc->qc_id = be32_to_cpu(str->qc_id);
1190 }
1191 
1192 int gfs2_quota_init(struct gfs2_sbd *sdp)
1193 {
1194 	struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1195 	u64 size = i_size_read(sdp->sd_qc_inode);
1196 	unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1197 	unsigned int x, slot = 0;
1198 	unsigned int found = 0;
1199 	u64 dblock;
1200 	u32 extlen = 0;
1201 	int error;
1202 
1203 	if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1204 		return -EIO;
1205 
1206 	sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1207 	sdp->sd_quota_chunks = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * PAGE_SIZE);
1208 
1209 	error = -ENOMEM;
1210 
1211 	sdp->sd_quota_bitmap = kcalloc(sdp->sd_quota_chunks,
1212 				       sizeof(unsigned char *), GFP_NOFS);
1213 	if (!sdp->sd_quota_bitmap)
1214 		return error;
1215 
1216 	for (x = 0; x < sdp->sd_quota_chunks; x++) {
1217 		sdp->sd_quota_bitmap[x] = kzalloc(PAGE_SIZE, GFP_NOFS);
1218 		if (!sdp->sd_quota_bitmap[x])
1219 			goto fail;
1220 	}
1221 
1222 	for (x = 0; x < blocks; x++) {
1223 		struct buffer_head *bh;
1224 		unsigned int y;
1225 
1226 		if (!extlen) {
1227 			int new = 0;
1228 			error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1229 			if (error)
1230 				goto fail;
1231 		}
1232 		error = -EIO;
1233 		bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1234 		if (!bh)
1235 			goto fail;
1236 		if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1237 			brelse(bh);
1238 			goto fail;
1239 		}
1240 
1241 		for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1242 		     y++, slot++) {
1243 			struct gfs2_quota_change_host qc;
1244 			struct gfs2_quota_data *qd;
1245 
1246 			gfs2_quota_change_in(&qc, bh->b_data +
1247 					  sizeof(struct gfs2_meta_header) +
1248 					  y * sizeof(struct gfs2_quota_change));
1249 			if (!qc.qc_change)
1250 				continue;
1251 
1252 			error = qd_alloc(sdp, (qc.qc_flags & GFS2_QCF_USER),
1253 					 qc.qc_id, &qd);
1254 			if (error) {
1255 				brelse(bh);
1256 				goto fail;
1257 			}
1258 
1259 			set_bit(QDF_CHANGE, &qd->qd_flags);
1260 			qd->qd_change = qc.qc_change;
1261 			qd->qd_slot = slot;
1262 			qd->qd_slot_count = 1;
1263 
1264 			spin_lock(&qd_lru_lock);
1265 			gfs2_icbit_munge(sdp, sdp->sd_quota_bitmap, slot, 1);
1266 			list_add(&qd->qd_list, &sdp->sd_quota_list);
1267 			atomic_inc(&sdp->sd_quota_count);
1268 			spin_unlock(&qd_lru_lock);
1269 
1270 			found++;
1271 		}
1272 
1273 		brelse(bh);
1274 		dblock++;
1275 		extlen--;
1276 	}
1277 
1278 	if (found)
1279 		fs_info(sdp, "found %u quota changes\n", found);
1280 
1281 	return 0;
1282 
1283 fail:
1284 	gfs2_quota_cleanup(sdp);
1285 	return error;
1286 }
1287 
1288 void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1289 {
1290 	struct list_head *head = &sdp->sd_quota_list;
1291 	struct gfs2_quota_data *qd;
1292 	unsigned int x;
1293 
1294 	spin_lock(&qd_lru_lock);
1295 	while (!list_empty(head)) {
1296 		qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1297 
1298 		if (atomic_read(&qd->qd_count) > 1 ||
1299 		    (atomic_read(&qd->qd_count) &&
1300 		     !test_bit(QDF_CHANGE, &qd->qd_flags))) {
1301 			list_move(&qd->qd_list, head);
1302 			spin_unlock(&qd_lru_lock);
1303 			schedule();
1304 			spin_lock(&qd_lru_lock);
1305 			continue;
1306 		}
1307 
1308 		list_del(&qd->qd_list);
1309 		/* Also remove if this qd exists in the reclaim list */
1310 		if (!list_empty(&qd->qd_reclaim)) {
1311 			list_del_init(&qd->qd_reclaim);
1312 			atomic_dec(&qd_lru_count);
1313 		}
1314 		atomic_dec(&sdp->sd_quota_count);
1315 		spin_unlock(&qd_lru_lock);
1316 
1317 		if (!atomic_read(&qd->qd_count)) {
1318 			gfs2_assert_warn(sdp, !qd->qd_change);
1319 			gfs2_assert_warn(sdp, !qd->qd_slot_count);
1320 		} else
1321 			gfs2_assert_warn(sdp, qd->qd_slot_count == 1);
1322 		gfs2_assert_warn(sdp, !qd->qd_bh_count);
1323 
1324 		gfs2_glock_put(qd->qd_gl);
1325 		kmem_cache_free(gfs2_quotad_cachep, qd);
1326 
1327 		spin_lock(&qd_lru_lock);
1328 	}
1329 	spin_unlock(&qd_lru_lock);
1330 
1331 	gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1332 
1333 	if (sdp->sd_quota_bitmap) {
1334 		for (x = 0; x < sdp->sd_quota_chunks; x++)
1335 			kfree(sdp->sd_quota_bitmap[x]);
1336 		kfree(sdp->sd_quota_bitmap);
1337 	}
1338 }
1339 
1340 static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1341 {
1342 	if (error == 0 || error == -EROFS)
1343 		return;
1344 	if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1345 		fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1346 }
1347 
1348 static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1349 			       int (*fxn)(struct super_block *sb, int type),
1350 			       unsigned long t, unsigned long *timeo,
1351 			       unsigned int *new_timeo)
1352 {
1353 	if (t >= *timeo) {
1354 		int error = fxn(sdp->sd_vfs, 0);
1355 		quotad_error(sdp, msg, error);
1356 		*timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1357 	} else {
1358 		*timeo -= t;
1359 	}
1360 }
1361 
1362 static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1363 {
1364 	struct gfs2_inode *ip;
1365 
1366 	while(1) {
1367 		ip = NULL;
1368 		spin_lock(&sdp->sd_trunc_lock);
1369 		if (!list_empty(&sdp->sd_trunc_list)) {
1370 			ip = list_entry(sdp->sd_trunc_list.next,
1371 					struct gfs2_inode, i_trunc_list);
1372 			list_del_init(&ip->i_trunc_list);
1373 		}
1374 		spin_unlock(&sdp->sd_trunc_lock);
1375 		if (ip == NULL)
1376 			return;
1377 		gfs2_glock_finish_truncate(ip);
1378 	}
1379 }
1380 
1381 void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1382 	if (!sdp->sd_statfs_force_sync) {
1383 		sdp->sd_statfs_force_sync = 1;
1384 		wake_up(&sdp->sd_quota_wait);
1385 	}
1386 }
1387 
1388 
1389 /**
1390  * gfs2_quotad - Write cached quota changes into the quota file
1391  * @sdp: Pointer to GFS2 superblock
1392  *
1393  */
1394 
1395 int gfs2_quotad(void *data)
1396 {
1397 	struct gfs2_sbd *sdp = data;
1398 	struct gfs2_tune *tune = &sdp->sd_tune;
1399 	unsigned long statfs_timeo = 0;
1400 	unsigned long quotad_timeo = 0;
1401 	unsigned long t = 0;
1402 	DEFINE_WAIT(wait);
1403 	int empty;
1404 
1405 	while (!kthread_should_stop()) {
1406 
1407 		/* Update the master statfs file */
1408 		if (sdp->sd_statfs_force_sync) {
1409 			int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1410 			quotad_error(sdp, "statfs", error);
1411 			statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1412 		}
1413 		else
1414 			quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1415 				   	   &statfs_timeo,
1416 					   &tune->gt_statfs_quantum);
1417 
1418 		/* Update quota file */
1419 		quotad_check_timeo(sdp, "sync", gfs2_quota_sync_timeo, t,
1420 				   &quotad_timeo, &tune->gt_quota_quantum);
1421 
1422 		/* Check for & recover partially truncated inodes */
1423 		quotad_check_trunc_list(sdp);
1424 
1425 		try_to_freeze();
1426 
1427 		t = min(quotad_timeo, statfs_timeo);
1428 
1429 		prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1430 		spin_lock(&sdp->sd_trunc_lock);
1431 		empty = list_empty(&sdp->sd_trunc_list);
1432 		spin_unlock(&sdp->sd_trunc_lock);
1433 		if (empty && !sdp->sd_statfs_force_sync)
1434 			t -= schedule_timeout(t);
1435 		else
1436 			t = 0;
1437 		finish_wait(&sdp->sd_quota_wait, &wait);
1438 	}
1439 
1440 	return 0;
1441 }
1442 
1443 static int gfs2_quota_get_xstate(struct super_block *sb,
1444 				 struct fs_quota_stat *fqs)
1445 {
1446 	struct gfs2_sbd *sdp = sb->s_fs_info;
1447 
1448 	memset(fqs, 0, sizeof(struct fs_quota_stat));
1449 	fqs->qs_version = FS_QSTAT_VERSION;
1450 
1451 	switch (sdp->sd_args.ar_quota) {
1452 	case GFS2_QUOTA_ON:
1453 		fqs->qs_flags |= (FS_QUOTA_UDQ_ENFD | FS_QUOTA_GDQ_ENFD);
1454 		/*FALLTHRU*/
1455 	case GFS2_QUOTA_ACCOUNT:
1456 		fqs->qs_flags |= (FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT);
1457 		break;
1458 	case GFS2_QUOTA_OFF:
1459 		break;
1460 	}
1461 
1462 	if (sdp->sd_quota_inode) {
1463 		fqs->qs_uquota.qfs_ino = GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1464 		fqs->qs_uquota.qfs_nblks = sdp->sd_quota_inode->i_blocks;
1465 	}
1466 	fqs->qs_uquota.qfs_nextents = 1; /* unsupported */
1467 	fqs->qs_gquota = fqs->qs_uquota; /* its the same inode in both cases */
1468 	fqs->qs_incoredqs = atomic_read(&qd_lru_count);
1469 	return 0;
1470 }
1471 
1472 static int gfs2_get_dqblk(struct super_block *sb, int type, qid_t id,
1473 			  struct fs_disk_quota *fdq)
1474 {
1475 	struct gfs2_sbd *sdp = sb->s_fs_info;
1476 	struct gfs2_quota_lvb *qlvb;
1477 	struct gfs2_quota_data *qd;
1478 	struct gfs2_holder q_gh;
1479 	int error;
1480 
1481 	memset(fdq, 0, sizeof(struct fs_disk_quota));
1482 
1483 	if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1484 		return -ESRCH; /* Crazy XFS error code */
1485 
1486 	if (type == USRQUOTA)
1487 		type = QUOTA_USER;
1488 	else if (type == GRPQUOTA)
1489 		type = QUOTA_GROUP;
1490 	else
1491 		return -EINVAL;
1492 
1493 	error = qd_get(sdp, type, id, &qd);
1494 	if (error)
1495 		return error;
1496 	error = do_glock(qd, FORCE, &q_gh);
1497 	if (error)
1498 		goto out;
1499 
1500 	qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb;
1501 	fdq->d_version = FS_DQUOT_VERSION;
1502 	fdq->d_flags = (type == QUOTA_USER) ? FS_USER_QUOTA : FS_GROUP_QUOTA;
1503 	fdq->d_id = id;
1504 	fdq->d_blk_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_fsb2bb_shift;
1505 	fdq->d_blk_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_fsb2bb_shift;
1506 	fdq->d_bcount = be64_to_cpu(qlvb->qb_value) << sdp->sd_fsb2bb_shift;
1507 
1508 	gfs2_glock_dq_uninit(&q_gh);
1509 out:
1510 	qd_put(qd);
1511 	return error;
1512 }
1513 
1514 /* GFS2 only supports a subset of the XFS fields */
1515 #define GFS2_FIELDMASK (FS_DQ_BSOFT|FS_DQ_BHARD|FS_DQ_BCOUNT)
1516 
1517 static int gfs2_set_dqblk(struct super_block *sb, int type, qid_t id,
1518 			  struct fs_disk_quota *fdq)
1519 {
1520 	struct gfs2_sbd *sdp = sb->s_fs_info;
1521 	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1522 	struct gfs2_quota_data *qd;
1523 	struct gfs2_holder q_gh, i_gh;
1524 	unsigned int data_blocks, ind_blocks;
1525 	unsigned int blocks = 0;
1526 	int alloc_required;
1527 	loff_t offset;
1528 	int error;
1529 
1530 	if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1531 		return -ESRCH; /* Crazy XFS error code */
1532 
1533 	switch(type) {
1534 	case USRQUOTA:
1535 		type = QUOTA_USER;
1536 		if (fdq->d_flags != FS_USER_QUOTA)
1537 			return -EINVAL;
1538 		break;
1539 	case GRPQUOTA:
1540 		type = QUOTA_GROUP;
1541 		if (fdq->d_flags != FS_GROUP_QUOTA)
1542 			return -EINVAL;
1543 		break;
1544 	default:
1545 		return -EINVAL;
1546 	}
1547 
1548 	if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1549 		return -EINVAL;
1550 	if (fdq->d_id != id)
1551 		return -EINVAL;
1552 
1553 	error = qd_get(sdp, type, id, &qd);
1554 	if (error)
1555 		return error;
1556 
1557 	error = gfs2_rs_alloc(ip);
1558 	if (error)
1559 		goto out_put;
1560 
1561 	mutex_lock(&ip->i_inode.i_mutex);
1562 	error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1563 	if (error)
1564 		goto out_unlockput;
1565 	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1566 	if (error)
1567 		goto out_q;
1568 
1569 	/* Check for existing entry, if none then alloc new blocks */
1570 	error = update_qd(sdp, qd);
1571 	if (error)
1572 		goto out_i;
1573 
1574 	/* If nothing has changed, this is a no-op */
1575 	if ((fdq->d_fieldmask & FS_DQ_BSOFT) &&
1576 	    ((fdq->d_blk_softlimit >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1577 		fdq->d_fieldmask ^= FS_DQ_BSOFT;
1578 
1579 	if ((fdq->d_fieldmask & FS_DQ_BHARD) &&
1580 	    ((fdq->d_blk_hardlimit >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1581 		fdq->d_fieldmask ^= FS_DQ_BHARD;
1582 
1583 	if ((fdq->d_fieldmask & FS_DQ_BCOUNT) &&
1584 	    ((fdq->d_bcount >> sdp->sd_fsb2bb_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1585 		fdq->d_fieldmask ^= FS_DQ_BCOUNT;
1586 
1587 	if (fdq->d_fieldmask == 0)
1588 		goto out_i;
1589 
1590 	offset = qd2offset(qd);
1591 	alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1592 	if (gfs2_is_stuffed(ip))
1593 		alloc_required = 1;
1594 	if (alloc_required) {
1595 		gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1596 				       &data_blocks, &ind_blocks);
1597 		blocks = 1 + data_blocks + ind_blocks;
1598 		error = gfs2_inplace_reserve(ip, blocks);
1599 		if (error)
1600 			goto out_i;
1601 		blocks += gfs2_rg_blocks(ip);
1602 	}
1603 
1604 	/* Some quotas span block boundaries and can update two blocks,
1605 	   adding an extra block to the transaction to handle such quotas */
1606 	error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1607 	if (error)
1608 		goto out_release;
1609 
1610 	/* Apply changes */
1611 	error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1612 
1613 	gfs2_trans_end(sdp);
1614 out_release:
1615 	if (alloc_required)
1616 		gfs2_inplace_release(ip);
1617 out_i:
1618 	gfs2_glock_dq_uninit(&i_gh);
1619 out_q:
1620 	gfs2_glock_dq_uninit(&q_gh);
1621 out_unlockput:
1622 	mutex_unlock(&ip->i_inode.i_mutex);
1623 out_put:
1624 	qd_put(qd);
1625 	return error;
1626 }
1627 
1628 const struct quotactl_ops gfs2_quotactl_ops = {
1629 	.quota_sync     = gfs2_quota_sync,
1630 	.get_xstate     = gfs2_quota_get_xstate,
1631 	.get_dqblk	= gfs2_get_dqblk,
1632 	.set_dqblk	= gfs2_set_dqblk,
1633 };
1634