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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
40
41#include <linux/sched.h>
42#include <linux/slab.h>
43#include <linux/mm.h>
44#include <linux/spinlock.h>
45#include <linux/completion.h>
46#include <linux/buffer_head.h>
47#include <linux/sort.h>
48#include <linux/fs.h>
49#include <linux/bio.h>
50#include <linux/gfs2_ondisk.h>
51#include <linux/kthread.h>
52#include <linux/freezer.h>
53#include <linux/quota.h>
54#include <linux/dqblk_xfs.h>
55#include <linux/lockref.h>
56#include <linux/list_lru.h>
57#include <linux/rcupdate.h>
58#include <linux/rculist_bl.h>
59#include <linux/bit_spinlock.h>
60#include <linux/jhash.h>
61#include <linux/vmalloc.h>
62
63#include "gfs2.h"
64#include "incore.h"
65#include "bmap.h"
66#include "glock.h"
67#include "glops.h"
68#include "log.h"
69#include "meta_io.h"
70#include "quota.h"
71#include "rgrp.h"
72#include "super.h"
73#include "trans.h"
74#include "inode.h"
75#include "util.h"
76
77#define GFS2_QD_HASH_SHIFT      12
78#define GFS2_QD_HASH_SIZE       (1 << GFS2_QD_HASH_SHIFT)
79#define GFS2_QD_HASH_MASK       (GFS2_QD_HASH_SIZE - 1)
80
81/* Lock order: qd_lock -> bucket lock -> qd->lockref.lock -> lru lock */
82/*                     -> sd_bitmap_lock                              */
83static DEFINE_SPINLOCK(qd_lock);
84struct list_lru gfs2_qd_lru;
85
86static struct hlist_bl_head qd_hash_table[GFS2_QD_HASH_SIZE];
87
88static unsigned int gfs2_qd_hash(const struct gfs2_sbd *sdp,
89				 const struct kqid qid)
90{
91	unsigned int h;
92
93	h = jhash(&sdp, sizeof(struct gfs2_sbd *), 0);
94	h = jhash(&qid, sizeof(struct kqid), h);
95
96	return h & GFS2_QD_HASH_MASK;
97}
98
99static inline void spin_lock_bucket(unsigned int hash)
100{
101        hlist_bl_lock(&qd_hash_table[hash]);
102}
103
104static inline void spin_unlock_bucket(unsigned int hash)
105{
106        hlist_bl_unlock(&qd_hash_table[hash]);
107}
108
109static void gfs2_qd_dealloc(struct rcu_head *rcu)
110{
111	struct gfs2_quota_data *qd = container_of(rcu, struct gfs2_quota_data, qd_rcu);
112	kmem_cache_free(gfs2_quotad_cachep, qd);
113}
114
115static void gfs2_qd_dispose(struct list_head *list)
116{
117	struct gfs2_quota_data *qd;
118	struct gfs2_sbd *sdp;
119
120	while (!list_empty(list)) {
121		qd = list_entry(list->next, struct gfs2_quota_data, qd_lru);
122		sdp = qd->qd_gl->gl_sbd;
123
124		list_del(&qd->qd_lru);
125
126		/* Free from the filesystem-specific list */
127		spin_lock(&qd_lock);
128		list_del(&qd->qd_list);
129		spin_unlock(&qd_lock);
130
131		spin_lock_bucket(qd->qd_hash);
132		hlist_bl_del_rcu(&qd->qd_hlist);
133		spin_unlock_bucket(qd->qd_hash);
134
135		gfs2_assert_warn(sdp, !qd->qd_change);
136		gfs2_assert_warn(sdp, !qd->qd_slot_count);
137		gfs2_assert_warn(sdp, !qd->qd_bh_count);
138
139		gfs2_glock_put(qd->qd_gl);
140		atomic_dec(&sdp->sd_quota_count);
141
142		/* Delete it from the common reclaim list */
143		call_rcu(&qd->qd_rcu, gfs2_qd_dealloc);
144	}
145}
146
147
148static enum lru_status gfs2_qd_isolate(struct list_head *item,
149		struct list_lru_one *lru, spinlock_t *lru_lock, void *arg)
150{
151	struct list_head *dispose = arg;
152	struct gfs2_quota_data *qd = list_entry(item, struct gfs2_quota_data, qd_lru);
153
154	if (!spin_trylock(&qd->qd_lockref.lock))
155		return LRU_SKIP;
156
157	if (qd->qd_lockref.count == 0) {
158		lockref_mark_dead(&qd->qd_lockref);
159		list_lru_isolate_move(lru, &qd->qd_lru, dispose);
160	}
161
162	spin_unlock(&qd->qd_lockref.lock);
163	return LRU_REMOVED;
164}
165
166static unsigned long gfs2_qd_shrink_scan(struct shrinker *shrink,
167					 struct shrink_control *sc)
168{
169	LIST_HEAD(dispose);
170	unsigned long freed;
171
172	if (!(sc->gfp_mask & __GFP_FS))
173		return SHRINK_STOP;
174
175	freed = list_lru_shrink_walk(&gfs2_qd_lru, sc,
176				     gfs2_qd_isolate, &dispose);
177
178	gfs2_qd_dispose(&dispose);
179
180	return freed;
181}
182
183static unsigned long gfs2_qd_shrink_count(struct shrinker *shrink,
184					  struct shrink_control *sc)
185{
186	return vfs_pressure_ratio(list_lru_shrink_count(&gfs2_qd_lru, sc));
187}
188
189struct shrinker gfs2_qd_shrinker = {
190	.count_objects = gfs2_qd_shrink_count,
191	.scan_objects = gfs2_qd_shrink_scan,
192	.seeks = DEFAULT_SEEKS,
193	.flags = SHRINKER_NUMA_AWARE,
194};
195
196
197static u64 qd2index(struct gfs2_quota_data *qd)
198{
199	struct kqid qid = qd->qd_id;
200	return (2 * (u64)from_kqid(&init_user_ns, qid)) +
201		((qid.type == USRQUOTA) ? 0 : 1);
202}
203
204static u64 qd2offset(struct gfs2_quota_data *qd)
205{
206	u64 offset;
207
208	offset = qd2index(qd);
209	offset *= sizeof(struct gfs2_quota);
210
211	return offset;
212}
213
214static struct gfs2_quota_data *qd_alloc(unsigned hash, struct gfs2_sbd *sdp, struct kqid qid)
215{
216	struct gfs2_quota_data *qd;
217	int error;
218
219	qd = kmem_cache_zalloc(gfs2_quotad_cachep, GFP_NOFS);
220	if (!qd)
221		return NULL;
222
223	qd->qd_sbd = sdp;
224	qd->qd_lockref.count = 1;
225	spin_lock_init(&qd->qd_lockref.lock);
226	qd->qd_id = qid;
227	qd->qd_slot = -1;
228	INIT_LIST_HEAD(&qd->qd_lru);
229	qd->qd_hash = hash;
230
231	error = gfs2_glock_get(sdp, qd2index(qd),
232			      &gfs2_quota_glops, CREATE, &qd->qd_gl);
233	if (error)
234		goto fail;
235
236	return qd;
237
238fail:
239	kmem_cache_free(gfs2_quotad_cachep, qd);
240	return NULL;
241}
242
243static struct gfs2_quota_data *gfs2_qd_search_bucket(unsigned int hash,
244						     const struct gfs2_sbd *sdp,
245						     struct kqid qid)
246{
247	struct gfs2_quota_data *qd;
248	struct hlist_bl_node *h;
249
250	hlist_bl_for_each_entry_rcu(qd, h, &qd_hash_table[hash], qd_hlist) {
251		if (!qid_eq(qd->qd_id, qid))
252			continue;
253		if (qd->qd_sbd != sdp)
254			continue;
255		if (lockref_get_not_dead(&qd->qd_lockref)) {
256			list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
257			return qd;
258		}
259	}
260
261	return NULL;
262}
263
264
265static int qd_get(struct gfs2_sbd *sdp, struct kqid qid,
266		  struct gfs2_quota_data **qdp)
267{
268	struct gfs2_quota_data *qd, *new_qd;
269	unsigned int hash = gfs2_qd_hash(sdp, qid);
270
271	rcu_read_lock();
272	*qdp = qd = gfs2_qd_search_bucket(hash, sdp, qid);
273	rcu_read_unlock();
274
275	if (qd)
276		return 0;
277
278	new_qd = qd_alloc(hash, sdp, qid);
279	if (!new_qd)
280		return -ENOMEM;
281
282	spin_lock(&qd_lock);
283	spin_lock_bucket(hash);
284	*qdp = qd = gfs2_qd_search_bucket(hash, sdp, qid);
285	if (qd == NULL) {
286		*qdp = new_qd;
287		list_add(&new_qd->qd_list, &sdp->sd_quota_list);
288		hlist_bl_add_head_rcu(&new_qd->qd_hlist, &qd_hash_table[hash]);
289		atomic_inc(&sdp->sd_quota_count);
290	}
291	spin_unlock_bucket(hash);
292	spin_unlock(&qd_lock);
293
294	if (qd) {
295		gfs2_glock_put(new_qd->qd_gl);
296		kmem_cache_free(gfs2_quotad_cachep, new_qd);
297	}
298
299	return 0;
300}
301
302
303static void qd_hold(struct gfs2_quota_data *qd)
304{
305	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
306	gfs2_assert(sdp, !__lockref_is_dead(&qd->qd_lockref));
307	lockref_get(&qd->qd_lockref);
308}
309
310static void qd_put(struct gfs2_quota_data *qd)
311{
312	if (lockref_put_or_lock(&qd->qd_lockref))
313		return;
314
315	qd->qd_lockref.count = 0;
316	list_lru_add(&gfs2_qd_lru, &qd->qd_lru);
317	spin_unlock(&qd->qd_lockref.lock);
318
319}
320
321static int slot_get(struct gfs2_quota_data *qd)
322{
323	struct gfs2_sbd *sdp = qd->qd_sbd;
324	unsigned int bit;
325	int error = 0;
326
327	spin_lock(&sdp->sd_bitmap_lock);
328	if (qd->qd_slot_count != 0)
329		goto out;
330
331	error = -ENOSPC;
332	bit = find_first_zero_bit(sdp->sd_quota_bitmap, sdp->sd_quota_slots);
333	if (bit < sdp->sd_quota_slots) {
334		set_bit(bit, sdp->sd_quota_bitmap);
335		qd->qd_slot = bit;
336		error = 0;
337out:
338		qd->qd_slot_count++;
339	}
340	spin_unlock(&sdp->sd_bitmap_lock);
341
342	return error;
343}
344
345static void slot_hold(struct gfs2_quota_data *qd)
346{
347	struct gfs2_sbd *sdp = qd->qd_sbd;
348
349	spin_lock(&sdp->sd_bitmap_lock);
350	gfs2_assert(sdp, qd->qd_slot_count);
351	qd->qd_slot_count++;
352	spin_unlock(&sdp->sd_bitmap_lock);
353}
354
355static void slot_put(struct gfs2_quota_data *qd)
356{
357	struct gfs2_sbd *sdp = qd->qd_sbd;
358
359	spin_lock(&sdp->sd_bitmap_lock);
360	gfs2_assert(sdp, qd->qd_slot_count);
361	if (!--qd->qd_slot_count) {
362		BUG_ON(!test_and_clear_bit(qd->qd_slot, sdp->sd_quota_bitmap));
363		qd->qd_slot = -1;
364	}
365	spin_unlock(&sdp->sd_bitmap_lock);
366}
367
368static int bh_get(struct gfs2_quota_data *qd)
369{
370	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
371	struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
372	unsigned int block, offset;
373	struct buffer_head *bh;
374	int error;
375	struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
376
377	mutex_lock(&sdp->sd_quota_mutex);
378
379	if (qd->qd_bh_count++) {
380		mutex_unlock(&sdp->sd_quota_mutex);
381		return 0;
382	}
383
384	block = qd->qd_slot / sdp->sd_qc_per_block;
385	offset = qd->qd_slot % sdp->sd_qc_per_block;
386
387	bh_map.b_size = 1 << ip->i_inode.i_blkbits;
388	error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
389	if (error)
390		goto fail;
391	error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
392	if (error)
393		goto fail;
394	error = -EIO;
395	if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
396		goto fail_brelse;
397
398	qd->qd_bh = bh;
399	qd->qd_bh_qc = (struct gfs2_quota_change *)
400		(bh->b_data + sizeof(struct gfs2_meta_header) +
401		 offset * sizeof(struct gfs2_quota_change));
402
403	mutex_unlock(&sdp->sd_quota_mutex);
404
405	return 0;
406
407fail_brelse:
408	brelse(bh);
409fail:
410	qd->qd_bh_count--;
411	mutex_unlock(&sdp->sd_quota_mutex);
412	return error;
413}
414
415static void bh_put(struct gfs2_quota_data *qd)
416{
417	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
418
419	mutex_lock(&sdp->sd_quota_mutex);
420	gfs2_assert(sdp, qd->qd_bh_count);
421	if (!--qd->qd_bh_count) {
422		brelse(qd->qd_bh);
423		qd->qd_bh = NULL;
424		qd->qd_bh_qc = NULL;
425	}
426	mutex_unlock(&sdp->sd_quota_mutex);
427}
428
429static int qd_check_sync(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd,
430			 u64 *sync_gen)
431{
432	if (test_bit(QDF_LOCKED, &qd->qd_flags) ||
433	    !test_bit(QDF_CHANGE, &qd->qd_flags) ||
434	    (sync_gen && (qd->qd_sync_gen >= *sync_gen)))
435		return 0;
436
437	if (!lockref_get_not_dead(&qd->qd_lockref))
438		return 0;
439
440	list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
441	set_bit(QDF_LOCKED, &qd->qd_flags);
442	qd->qd_change_sync = qd->qd_change;
443	slot_hold(qd);
444	return 1;
445}
446
447static int qd_fish(struct gfs2_sbd *sdp, struct gfs2_quota_data **qdp)
448{
449	struct gfs2_quota_data *qd = NULL;
450	int error;
451	int found = 0;
452
453	*qdp = NULL;
454
455	if (sdp->sd_vfs->s_flags & MS_RDONLY)
456		return 0;
457
458	spin_lock(&qd_lock);
459
460	list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
461		found = qd_check_sync(sdp, qd, &sdp->sd_quota_sync_gen);
462		if (found)
463			break;
464	}
465
466	if (!found)
467		qd = NULL;
468
469	spin_unlock(&qd_lock);
470
471	if (qd) {
472		gfs2_assert_warn(sdp, qd->qd_change_sync);
473		error = bh_get(qd);
474		if (error) {
475			clear_bit(QDF_LOCKED, &qd->qd_flags);
476			slot_put(qd);
477			qd_put(qd);
478			return error;
479		}
480	}
481
482	*qdp = qd;
483
484	return 0;
485}
486
487static void qd_unlock(struct gfs2_quota_data *qd)
488{
489	gfs2_assert_warn(qd->qd_gl->gl_sbd,
490			 test_bit(QDF_LOCKED, &qd->qd_flags));
491	clear_bit(QDF_LOCKED, &qd->qd_flags);
492	bh_put(qd);
493	slot_put(qd);
494	qd_put(qd);
495}
496
497static int qdsb_get(struct gfs2_sbd *sdp, struct kqid qid,
498		    struct gfs2_quota_data **qdp)
499{
500	int error;
501
502	error = qd_get(sdp, qid, qdp);
503	if (error)
504		return error;
505
506	error = slot_get(*qdp);
507	if (error)
508		goto fail;
509
510	error = bh_get(*qdp);
511	if (error)
512		goto fail_slot;
513
514	return 0;
515
516fail_slot:
517	slot_put(*qdp);
518fail:
519	qd_put(*qdp);
520	return error;
521}
522
523static void qdsb_put(struct gfs2_quota_data *qd)
524{
525	bh_put(qd);
526	slot_put(qd);
527	qd_put(qd);
528}
529
530int gfs2_quota_hold(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
531{
532	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
533	struct gfs2_quota_data **qd;
534	int error;
535
536	if (ip->i_res == NULL) {
537		error = gfs2_rs_alloc(ip);
538		if (error)
539			return error;
540	}
541
542	qd = ip->i_res->rs_qa_qd;
543
544	if (gfs2_assert_warn(sdp, !ip->i_res->rs_qa_qd_num) ||
545	    gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags)))
546		return -EIO;
547
548	if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
549		return 0;
550
551	error = qdsb_get(sdp, make_kqid_uid(ip->i_inode.i_uid), qd);
552	if (error)
553		goto out;
554	ip->i_res->rs_qa_qd_num++;
555	qd++;
556
557	error = qdsb_get(sdp, make_kqid_gid(ip->i_inode.i_gid), qd);
558	if (error)
559		goto out;
560	ip->i_res->rs_qa_qd_num++;
561	qd++;
562
563	if (!uid_eq(uid, NO_UID_QUOTA_CHANGE) &&
564	    !uid_eq(uid, ip->i_inode.i_uid)) {
565		error = qdsb_get(sdp, make_kqid_uid(uid), qd);
566		if (error)
567			goto out;
568		ip->i_res->rs_qa_qd_num++;
569		qd++;
570	}
571
572	if (!gid_eq(gid, NO_GID_QUOTA_CHANGE) &&
573	    !gid_eq(gid, ip->i_inode.i_gid)) {
574		error = qdsb_get(sdp, make_kqid_gid(gid), qd);
575		if (error)
576			goto out;
577		ip->i_res->rs_qa_qd_num++;
578		qd++;
579	}
580
581out:
582	if (error)
583		gfs2_quota_unhold(ip);
584	return error;
585}
586
587void gfs2_quota_unhold(struct gfs2_inode *ip)
588{
589	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
590	unsigned int x;
591
592	if (ip->i_res == NULL)
593		return;
594	gfs2_assert_warn(sdp, !test_bit(GIF_QD_LOCKED, &ip->i_flags));
595
596	for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
597		qdsb_put(ip->i_res->rs_qa_qd[x]);
598		ip->i_res->rs_qa_qd[x] = NULL;
599	}
600	ip->i_res->rs_qa_qd_num = 0;
601}
602
603static int sort_qd(const void *a, const void *b)
604{
605	const struct gfs2_quota_data *qd_a = *(const struct gfs2_quota_data **)a;
606	const struct gfs2_quota_data *qd_b = *(const struct gfs2_quota_data **)b;
607
608	if (qid_lt(qd_a->qd_id, qd_b->qd_id))
609		return -1;
610	if (qid_lt(qd_b->qd_id, qd_a->qd_id))
611		return 1;
612	return 0;
613}
614
615static void do_qc(struct gfs2_quota_data *qd, s64 change)
616{
617	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
618	struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
619	struct gfs2_quota_change *qc = qd->qd_bh_qc;
620	s64 x;
621
622	mutex_lock(&sdp->sd_quota_mutex);
623	gfs2_trans_add_meta(ip->i_gl, qd->qd_bh);
624
625	if (!test_bit(QDF_CHANGE, &qd->qd_flags)) {
626		qc->qc_change = 0;
627		qc->qc_flags = 0;
628		if (qd->qd_id.type == USRQUOTA)
629			qc->qc_flags = cpu_to_be32(GFS2_QCF_USER);
630		qc->qc_id = cpu_to_be32(from_kqid(&init_user_ns, qd->qd_id));
631	}
632
633	x = be64_to_cpu(qc->qc_change) + change;
634	qc->qc_change = cpu_to_be64(x);
635
636	spin_lock(&qd_lock);
637	qd->qd_change = x;
638	spin_unlock(&qd_lock);
639
640	if (!x) {
641		gfs2_assert_warn(sdp, test_bit(QDF_CHANGE, &qd->qd_flags));
642		clear_bit(QDF_CHANGE, &qd->qd_flags);
643		qc->qc_flags = 0;
644		qc->qc_id = 0;
645		slot_put(qd);
646		qd_put(qd);
647	} else if (!test_and_set_bit(QDF_CHANGE, &qd->qd_flags)) {
648		qd_hold(qd);
649		slot_hold(qd);
650	}
651
652	mutex_unlock(&sdp->sd_quota_mutex);
653}
654
655/**
656 * gfs2_adjust_quota - adjust record of current block usage
657 * @ip: The quota inode
658 * @loc: Offset of the entry in the quota file
659 * @change: The amount of usage change to record
660 * @qd: The quota data
661 * @fdq: The updated limits to record
662 *
663 * This function was mostly borrowed from gfs2_block_truncate_page which was
664 * in turn mostly borrowed from ext3
665 *
666 * Returns: 0 or -ve on error
667 */
668
669static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc,
670			     s64 change, struct gfs2_quota_data *qd,
671			     struct qc_dqblk *fdq)
672{
673	struct inode *inode = &ip->i_inode;
674	struct gfs2_sbd *sdp = GFS2_SB(inode);
675	struct address_space *mapping = inode->i_mapping;
676	unsigned long index = loc >> PAGE_CACHE_SHIFT;
677	unsigned offset = loc & (PAGE_CACHE_SIZE - 1);
678	unsigned blocksize, iblock, pos;
679	struct buffer_head *bh;
680	struct page *page;
681	void *kaddr, *ptr;
682	struct gfs2_quota q;
683	int err, nbytes;
684	u64 size;
685
686	if (gfs2_is_stuffed(ip)) {
687		err = gfs2_unstuff_dinode(ip, NULL);
688		if (err)
689			return err;
690	}
691
692	memset(&q, 0, sizeof(struct gfs2_quota));
693	err = gfs2_internal_read(ip, (char *)&q, &loc, sizeof(q));
694	if (err < 0)
695		return err;
696
697	err = -EIO;
698	be64_add_cpu(&q.qu_value, change);
699	qd->qd_qb.qb_value = q.qu_value;
700	if (fdq) {
701		if (fdq->d_fieldmask & QC_SPC_SOFT) {
702			q.qu_warn = cpu_to_be64(fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift);
703			qd->qd_qb.qb_warn = q.qu_warn;
704		}
705		if (fdq->d_fieldmask & QC_SPC_HARD) {
706			q.qu_limit = cpu_to_be64(fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift);
707			qd->qd_qb.qb_limit = q.qu_limit;
708		}
709		if (fdq->d_fieldmask & QC_SPACE) {
710			q.qu_value = cpu_to_be64(fdq->d_space >> sdp->sd_sb.sb_bsize_shift);
711			qd->qd_qb.qb_value = q.qu_value;
712		}
713	}
714
715	/* Write the quota into the quota file on disk */
716	ptr = &q;
717	nbytes = sizeof(struct gfs2_quota);
718get_a_page:
719	page = find_or_create_page(mapping, index, GFP_NOFS);
720	if (!page)
721		return -ENOMEM;
722
723	blocksize = inode->i_sb->s_blocksize;
724	iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
725
726	if (!page_has_buffers(page))
727		create_empty_buffers(page, blocksize, 0);
728
729	bh = page_buffers(page);
730	pos = blocksize;
731	while (offset >= pos) {
732		bh = bh->b_this_page;
733		iblock++;
734		pos += blocksize;
735	}
736
737	if (!buffer_mapped(bh)) {
738		gfs2_block_map(inode, iblock, bh, 1);
739		if (!buffer_mapped(bh))
740			goto unlock_out;
741		/* If it's a newly allocated disk block for quota, zero it */
742		if (buffer_new(bh))
743			zero_user(page, pos - blocksize, bh->b_size);
744	}
745
746	if (PageUptodate(page))
747		set_buffer_uptodate(bh);
748
749	if (!buffer_uptodate(bh)) {
750		ll_rw_block(READ | REQ_META, 1, &bh);
751		wait_on_buffer(bh);
752		if (!buffer_uptodate(bh))
753			goto unlock_out;
754	}
755
756	gfs2_trans_add_data(ip->i_gl, bh);
757
758	kaddr = kmap_atomic(page);
759	if (offset + sizeof(struct gfs2_quota) > PAGE_CACHE_SIZE)
760		nbytes = PAGE_CACHE_SIZE - offset;
761	memcpy(kaddr + offset, ptr, nbytes);
762	flush_dcache_page(page);
763	kunmap_atomic(kaddr);
764	unlock_page(page);
765	page_cache_release(page);
766
767	/* If quota straddles page boundary, we need to update the rest of the
768	 * quota at the beginning of the next page */
769	if ((offset + sizeof(struct gfs2_quota)) > PAGE_CACHE_SIZE) {
770		ptr = ptr + nbytes;
771		nbytes = sizeof(struct gfs2_quota) - nbytes;
772		offset = 0;
773		index++;
774		goto get_a_page;
775	}
776
777	size = loc + sizeof(struct gfs2_quota);
778	if (size > inode->i_size)
779		i_size_write(inode, size);
780	inode->i_mtime = inode->i_atime = CURRENT_TIME;
781	mark_inode_dirty(inode);
782	set_bit(QDF_REFRESH, &qd->qd_flags);
783	return 0;
784
785unlock_out:
786	unlock_page(page);
787	page_cache_release(page);
788	return err;
789}
790
791static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
792{
793	struct gfs2_sbd *sdp = (*qda)->qd_gl->gl_sbd;
794	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
795	struct gfs2_alloc_parms ap = { .aflags = 0, };
796	unsigned int data_blocks, ind_blocks;
797	struct gfs2_holder *ghs, i_gh;
798	unsigned int qx, x;
799	struct gfs2_quota_data *qd;
800	unsigned reserved;
801	loff_t offset;
802	unsigned int nalloc = 0, blocks;
803	int error;
804
805	error = gfs2_rs_alloc(ip);
806	if (error)
807		return error;
808
809	gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
810			      &data_blocks, &ind_blocks);
811
812	ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS);
813	if (!ghs)
814		return -ENOMEM;
815
816	sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL);
817	mutex_lock(&ip->i_inode.i_mutex);
818	for (qx = 0; qx < num_qd; qx++) {
819		error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE,
820					   GL_NOCACHE, &ghs[qx]);
821		if (error)
822			goto out;
823	}
824
825	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
826	if (error)
827		goto out;
828
829	for (x = 0; x < num_qd; x++) {
830		offset = qd2offset(qda[x]);
831		if (gfs2_write_alloc_required(ip, offset,
832					      sizeof(struct gfs2_quota)))
833			nalloc++;
834	}
835
836	/*
837	 * 1 blk for unstuffing inode if stuffed. We add this extra
838	 * block to the reservation unconditionally. If the inode
839	 * doesn't need unstuffing, the block will be released to the
840	 * rgrp since it won't be allocated during the transaction
841	 */
842	/* +3 in the end for unstuffing block, inode size update block
843	 * and another block in case quota straddles page boundary and
844	 * two blocks need to be updated instead of 1 */
845	blocks = num_qd * data_blocks + RES_DINODE + num_qd + 3;
846
847	reserved = 1 + (nalloc * (data_blocks + ind_blocks));
848	ap.target = reserved;
849	error = gfs2_inplace_reserve(ip, &ap);
850	if (error)
851		goto out_alloc;
852
853	if (nalloc)
854		blocks += gfs2_rg_blocks(ip, reserved) + nalloc * ind_blocks + RES_STATFS;
855
856	error = gfs2_trans_begin(sdp, blocks, 0);
857	if (error)
858		goto out_ipres;
859
860	for (x = 0; x < num_qd; x++) {
861		qd = qda[x];
862		offset = qd2offset(qd);
863		error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, qd, NULL);
864		if (error)
865			goto out_end_trans;
866
867		do_qc(qd, -qd->qd_change_sync);
868		set_bit(QDF_REFRESH, &qd->qd_flags);
869	}
870
871	error = 0;
872
873out_end_trans:
874	gfs2_trans_end(sdp);
875out_ipres:
876	gfs2_inplace_release(ip);
877out_alloc:
878	gfs2_glock_dq_uninit(&i_gh);
879out:
880	while (qx--)
881		gfs2_glock_dq_uninit(&ghs[qx]);
882	mutex_unlock(&ip->i_inode.i_mutex);
883	kfree(ghs);
884	gfs2_log_flush(ip->i_gl->gl_sbd, ip->i_gl, NORMAL_FLUSH);
885	return error;
886}
887
888static int update_qd(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd)
889{
890	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
891	struct gfs2_quota q;
892	struct gfs2_quota_lvb *qlvb;
893	loff_t pos;
894	int error;
895
896	memset(&q, 0, sizeof(struct gfs2_quota));
897	pos = qd2offset(qd);
898	error = gfs2_internal_read(ip, (char *)&q, &pos, sizeof(q));
899	if (error < 0)
900		return error;
901
902	qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
903	qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC);
904	qlvb->__pad = 0;
905	qlvb->qb_limit = q.qu_limit;
906	qlvb->qb_warn = q.qu_warn;
907	qlvb->qb_value = q.qu_value;
908	qd->qd_qb = *qlvb;
909
910	return 0;
911}
912
913static int do_glock(struct gfs2_quota_data *qd, int force_refresh,
914		    struct gfs2_holder *q_gh)
915{
916	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
917	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
918	struct gfs2_holder i_gh;
919	int error;
920
921restart:
922	error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_SHARED, 0, q_gh);
923	if (error)
924		return error;
925
926	if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
927		force_refresh = FORCE;
928
929	qd->qd_qb = *(struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
930
931	if (force_refresh || qd->qd_qb.qb_magic != cpu_to_be32(GFS2_MAGIC)) {
932		gfs2_glock_dq_uninit(q_gh);
933		error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE,
934					   GL_NOCACHE, q_gh);
935		if (error)
936			return error;
937
938		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
939		if (error)
940			goto fail;
941
942		error = update_qd(sdp, qd);
943		if (error)
944			goto fail_gunlock;
945
946		gfs2_glock_dq_uninit(&i_gh);
947		gfs2_glock_dq_uninit(q_gh);
948		force_refresh = 0;
949		goto restart;
950	}
951
952	return 0;
953
954fail_gunlock:
955	gfs2_glock_dq_uninit(&i_gh);
956fail:
957	gfs2_glock_dq_uninit(q_gh);
958	return error;
959}
960
961int gfs2_quota_lock(struct gfs2_inode *ip, kuid_t uid, kgid_t gid)
962{
963	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
964	struct gfs2_quota_data *qd;
965	unsigned int x;
966	int error = 0;
967
968	error = gfs2_quota_hold(ip, uid, gid);
969	if (error)
970		return error;
971
972	if (capable(CAP_SYS_RESOURCE) ||
973	    sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
974		return 0;
975
976	sort(ip->i_res->rs_qa_qd, ip->i_res->rs_qa_qd_num,
977	     sizeof(struct gfs2_quota_data *), sort_qd, NULL);
978
979	for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
980		qd = ip->i_res->rs_qa_qd[x];
981		error = do_glock(qd, NO_FORCE, &ip->i_res->rs_qa_qd_ghs[x]);
982		if (error)
983			break;
984	}
985
986	if (!error)
987		set_bit(GIF_QD_LOCKED, &ip->i_flags);
988	else {
989		while (x--)
990			gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
991		gfs2_quota_unhold(ip);
992	}
993
994	return error;
995}
996
997static int need_sync(struct gfs2_quota_data *qd)
998{
999	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
1000	struct gfs2_tune *gt = &sdp->sd_tune;
1001	s64 value;
1002	unsigned int num, den;
1003	int do_sync = 1;
1004
1005	if (!qd->qd_qb.qb_limit)
1006		return 0;
1007
1008	spin_lock(&qd_lock);
1009	value = qd->qd_change;
1010	spin_unlock(&qd_lock);
1011
1012	spin_lock(&gt->gt_spin);
1013	num = gt->gt_quota_scale_num;
1014	den = gt->gt_quota_scale_den;
1015	spin_unlock(&gt->gt_spin);
1016
1017	if (value < 0)
1018		do_sync = 0;
1019	else if ((s64)be64_to_cpu(qd->qd_qb.qb_value) >=
1020		 (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1021		do_sync = 0;
1022	else {
1023		value *= gfs2_jindex_size(sdp) * num;
1024		value = div_s64(value, den);
1025		value += (s64)be64_to_cpu(qd->qd_qb.qb_value);
1026		if (value < (s64)be64_to_cpu(qd->qd_qb.qb_limit))
1027			do_sync = 0;
1028	}
1029
1030	return do_sync;
1031}
1032
1033void gfs2_quota_unlock(struct gfs2_inode *ip)
1034{
1035	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1036	struct gfs2_quota_data *qda[4];
1037	unsigned int count = 0;
1038	unsigned int x;
1039	int found;
1040
1041	if (!test_and_clear_bit(GIF_QD_LOCKED, &ip->i_flags))
1042		goto out;
1043
1044	for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1045		struct gfs2_quota_data *qd;
1046		int sync;
1047
1048		qd = ip->i_res->rs_qa_qd[x];
1049		sync = need_sync(qd);
1050
1051		gfs2_glock_dq_uninit(&ip->i_res->rs_qa_qd_ghs[x]);
1052		if (!sync)
1053			continue;
1054
1055		spin_lock(&qd_lock);
1056		found = qd_check_sync(sdp, qd, NULL);
1057		spin_unlock(&qd_lock);
1058
1059		if (!found)
1060			continue;
1061
1062		gfs2_assert_warn(sdp, qd->qd_change_sync);
1063		if (bh_get(qd)) {
1064			clear_bit(QDF_LOCKED, &qd->qd_flags);
1065			slot_put(qd);
1066			qd_put(qd);
1067			continue;
1068		}
1069
1070		qda[count++] = qd;
1071	}
1072
1073	if (count) {
1074		do_sync(count, qda);
1075		for (x = 0; x < count; x++)
1076			qd_unlock(qda[x]);
1077	}
1078
1079out:
1080	gfs2_quota_unhold(ip);
1081}
1082
1083#define MAX_LINE 256
1084
1085static int print_message(struct gfs2_quota_data *qd, char *type)
1086{
1087	struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
1088
1089	fs_info(sdp, "quota %s for %s %u\n",
1090		type,
1091		(qd->qd_id.type == USRQUOTA) ? "user" : "group",
1092		from_kqid(&init_user_ns, qd->qd_id));
1093
1094	return 0;
1095}
1096
1097/**
1098 * gfs2_quota_check - check if allocating new blocks will exceed quota
1099 * @ip:  The inode for which this check is being performed
1100 * @uid: The uid to check against
1101 * @gid: The gid to check against
1102 * @ap:  The allocation parameters. ap->target contains the requested
1103 *       blocks. ap->min_target, if set, contains the minimum blks
1104 *       requested.
1105 *
1106 * Returns: 0 on success.
1107 *                  min_req = ap->min_target ? ap->min_target : ap->target;
1108 *                  quota must allow atleast min_req blks for success and
1109 *                  ap->allowed is set to the number of blocks allowed
1110 *
1111 *          -EDQUOT otherwise, quota violation. ap->allowed is set to number
1112 *                  of blocks available.
1113 */
1114int gfs2_quota_check(struct gfs2_inode *ip, kuid_t uid, kgid_t gid,
1115		     struct gfs2_alloc_parms *ap)
1116{
1117	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1118	struct gfs2_quota_data *qd;
1119	s64 value, warn, limit;
1120	unsigned int x;
1121	int error = 0;
1122
1123	ap->allowed = UINT_MAX; /* Assume we are permitted a whole lot */
1124	if (!test_bit(GIF_QD_LOCKED, &ip->i_flags))
1125		return 0;
1126
1127        if (sdp->sd_args.ar_quota != GFS2_QUOTA_ON)
1128                return 0;
1129
1130	for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1131		qd = ip->i_res->rs_qa_qd[x];
1132
1133		if (!(qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1134		      qid_eq(qd->qd_id, make_kqid_gid(gid))))
1135			continue;
1136
1137		warn = (s64)be64_to_cpu(qd->qd_qb.qb_warn);
1138		limit = (s64)be64_to_cpu(qd->qd_qb.qb_limit);
1139		value = (s64)be64_to_cpu(qd->qd_qb.qb_value);
1140		spin_lock(&qd_lock);
1141		value += qd->qd_change;
1142		spin_unlock(&qd_lock);
1143
1144		if (limit > 0 && (limit - value) < ap->allowed)
1145			ap->allowed = limit - value;
1146		/* If we can't meet the target */
1147		if (limit && limit < (value + (s64)ap->target)) {
1148			/* If no min_target specified or we don't meet
1149			 * min_target, return -EDQUOT */
1150			if (!ap->min_target || ap->min_target > ap->allowed) {
1151				print_message(qd, "exceeded");
1152				quota_send_warning(qd->qd_id,
1153						   sdp->sd_vfs->s_dev,
1154						   QUOTA_NL_BHARDWARN);
1155				error = -EDQUOT;
1156				break;
1157			}
1158		} else if (warn && warn < value &&
1159			   time_after_eq(jiffies, qd->qd_last_warn +
1160					 gfs2_tune_get(sdp, gt_quota_warn_period)
1161					 * HZ)) {
1162			quota_send_warning(qd->qd_id,
1163					   sdp->sd_vfs->s_dev, QUOTA_NL_BSOFTWARN);
1164			error = print_message(qd, "warning");
1165			qd->qd_last_warn = jiffies;
1166		}
1167	}
1168	return error;
1169}
1170
1171void gfs2_quota_change(struct gfs2_inode *ip, s64 change,
1172		       kuid_t uid, kgid_t gid)
1173{
1174	struct gfs2_quota_data *qd;
1175	unsigned int x;
1176
1177	if (gfs2_assert_warn(GFS2_SB(&ip->i_inode), change))
1178		return;
1179	if (ip->i_diskflags & GFS2_DIF_SYSTEM)
1180		return;
1181
1182	for (x = 0; x < ip->i_res->rs_qa_qd_num; x++) {
1183		qd = ip->i_res->rs_qa_qd[x];
1184
1185		if (qid_eq(qd->qd_id, make_kqid_uid(uid)) ||
1186		    qid_eq(qd->qd_id, make_kqid_gid(gid))) {
1187			do_qc(qd, change);
1188		}
1189	}
1190}
1191
1192int gfs2_quota_sync(struct super_block *sb, int type)
1193{
1194	struct gfs2_sbd *sdp = sb->s_fs_info;
1195	struct gfs2_quota_data **qda;
1196	unsigned int max_qd = PAGE_SIZE/sizeof(struct gfs2_holder);
1197	unsigned int num_qd;
1198	unsigned int x;
1199	int error = 0;
1200
1201	qda = kcalloc(max_qd, sizeof(struct gfs2_quota_data *), GFP_KERNEL);
1202	if (!qda)
1203		return -ENOMEM;
1204
1205	mutex_lock(&sdp->sd_quota_sync_mutex);
1206	sdp->sd_quota_sync_gen++;
1207
1208	do {
1209		num_qd = 0;
1210
1211		for (;;) {
1212			error = qd_fish(sdp, qda + num_qd);
1213			if (error || !qda[num_qd])
1214				break;
1215			if (++num_qd == max_qd)
1216				break;
1217		}
1218
1219		if (num_qd) {
1220			if (!error)
1221				error = do_sync(num_qd, qda);
1222			if (!error)
1223				for (x = 0; x < num_qd; x++)
1224					qda[x]->qd_sync_gen =
1225						sdp->sd_quota_sync_gen;
1226
1227			for (x = 0; x < num_qd; x++)
1228				qd_unlock(qda[x]);
1229		}
1230	} while (!error && num_qd == max_qd);
1231
1232	mutex_unlock(&sdp->sd_quota_sync_mutex);
1233	kfree(qda);
1234
1235	return error;
1236}
1237
1238int gfs2_quota_refresh(struct gfs2_sbd *sdp, struct kqid qid)
1239{
1240	struct gfs2_quota_data *qd;
1241	struct gfs2_holder q_gh;
1242	int error;
1243
1244	error = qd_get(sdp, qid, &qd);
1245	if (error)
1246		return error;
1247
1248	error = do_glock(qd, FORCE, &q_gh);
1249	if (!error)
1250		gfs2_glock_dq_uninit(&q_gh);
1251
1252	qd_put(qd);
1253	return error;
1254}
1255
1256int gfs2_quota_init(struct gfs2_sbd *sdp)
1257{
1258	struct gfs2_inode *ip = GFS2_I(sdp->sd_qc_inode);
1259	u64 size = i_size_read(sdp->sd_qc_inode);
1260	unsigned int blocks = size >> sdp->sd_sb.sb_bsize_shift;
1261	unsigned int x, slot = 0;
1262	unsigned int found = 0;
1263	unsigned int hash;
1264	unsigned int bm_size;
1265	u64 dblock;
1266	u32 extlen = 0;
1267	int error;
1268
1269	if (gfs2_check_internal_file_size(sdp->sd_qc_inode, 1, 64 << 20))
1270		return -EIO;
1271
1272	sdp->sd_quota_slots = blocks * sdp->sd_qc_per_block;
1273	bm_size = DIV_ROUND_UP(sdp->sd_quota_slots, 8 * sizeof(unsigned long));
1274	bm_size *= sizeof(unsigned long);
1275	error = -ENOMEM;
1276	sdp->sd_quota_bitmap = kzalloc(bm_size, GFP_NOFS | __GFP_NOWARN);
1277	if (sdp->sd_quota_bitmap == NULL)
1278		sdp->sd_quota_bitmap = __vmalloc(bm_size, GFP_NOFS |
1279						 __GFP_ZERO, PAGE_KERNEL);
1280	if (!sdp->sd_quota_bitmap)
1281		return error;
1282
1283	for (x = 0; x < blocks; x++) {
1284		struct buffer_head *bh;
1285		const struct gfs2_quota_change *qc;
1286		unsigned int y;
1287
1288		if (!extlen) {
1289			int new = 0;
1290			error = gfs2_extent_map(&ip->i_inode, x, &new, &dblock, &extlen);
1291			if (error)
1292				goto fail;
1293		}
1294		error = -EIO;
1295		bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
1296		if (!bh)
1297			goto fail;
1298		if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC)) {
1299			brelse(bh);
1300			goto fail;
1301		}
1302
1303		qc = (const struct gfs2_quota_change *)(bh->b_data + sizeof(struct gfs2_meta_header));
1304		for (y = 0; y < sdp->sd_qc_per_block && slot < sdp->sd_quota_slots;
1305		     y++, slot++) {
1306			struct gfs2_quota_data *qd;
1307			s64 qc_change = be64_to_cpu(qc->qc_change);
1308			u32 qc_flags = be32_to_cpu(qc->qc_flags);
1309			enum quota_type qtype = (qc_flags & GFS2_QCF_USER) ?
1310						USRQUOTA : GRPQUOTA;
1311			struct kqid qc_id = make_kqid(&init_user_ns, qtype,
1312						      be32_to_cpu(qc->qc_id));
1313			qc++;
1314			if (!qc_change)
1315				continue;
1316
1317			hash = gfs2_qd_hash(sdp, qc_id);
1318			qd = qd_alloc(hash, sdp, qc_id);
1319			if (qd == NULL) {
1320				brelse(bh);
1321				goto fail;
1322			}
1323
1324			set_bit(QDF_CHANGE, &qd->qd_flags);
1325			qd->qd_change = qc_change;
1326			qd->qd_slot = slot;
1327			qd->qd_slot_count = 1;
1328
1329			spin_lock(&qd_lock);
1330			BUG_ON(test_and_set_bit(slot, sdp->sd_quota_bitmap));
1331			list_add(&qd->qd_list, &sdp->sd_quota_list);
1332			atomic_inc(&sdp->sd_quota_count);
1333			spin_unlock(&qd_lock);
1334
1335			spin_lock_bucket(hash);
1336			hlist_bl_add_head_rcu(&qd->qd_hlist, &qd_hash_table[hash]);
1337			spin_unlock_bucket(hash);
1338
1339			found++;
1340		}
1341
1342		brelse(bh);
1343		dblock++;
1344		extlen--;
1345	}
1346
1347	if (found)
1348		fs_info(sdp, "found %u quota changes\n", found);
1349
1350	return 0;
1351
1352fail:
1353	gfs2_quota_cleanup(sdp);
1354	return error;
1355}
1356
1357void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
1358{
1359	struct list_head *head = &sdp->sd_quota_list;
1360	struct gfs2_quota_data *qd;
1361
1362	spin_lock(&qd_lock);
1363	while (!list_empty(head)) {
1364		qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
1365
1366		list_del(&qd->qd_list);
1367
1368		/* Also remove if this qd exists in the reclaim list */
1369		list_lru_del(&gfs2_qd_lru, &qd->qd_lru);
1370		atomic_dec(&sdp->sd_quota_count);
1371		spin_unlock(&qd_lock);
1372
1373		spin_lock_bucket(qd->qd_hash);
1374		hlist_bl_del_rcu(&qd->qd_hlist);
1375		spin_unlock_bucket(qd->qd_hash);
1376
1377		gfs2_assert_warn(sdp, !qd->qd_change);
1378		gfs2_assert_warn(sdp, !qd->qd_slot_count);
1379		gfs2_assert_warn(sdp, !qd->qd_bh_count);
1380
1381		gfs2_glock_put(qd->qd_gl);
1382		call_rcu(&qd->qd_rcu, gfs2_qd_dealloc);
1383
1384		spin_lock(&qd_lock);
1385	}
1386	spin_unlock(&qd_lock);
1387
1388	gfs2_assert_warn(sdp, !atomic_read(&sdp->sd_quota_count));
1389
1390	kvfree(sdp->sd_quota_bitmap);
1391	sdp->sd_quota_bitmap = NULL;
1392}
1393
1394static void quotad_error(struct gfs2_sbd *sdp, const char *msg, int error)
1395{
1396	if (error == 0 || error == -EROFS)
1397		return;
1398	if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
1399		fs_err(sdp, "gfs2_quotad: %s error %d\n", msg, error);
1400}
1401
1402static void quotad_check_timeo(struct gfs2_sbd *sdp, const char *msg,
1403			       int (*fxn)(struct super_block *sb, int type),
1404			       unsigned long t, unsigned long *timeo,
1405			       unsigned int *new_timeo)
1406{
1407	if (t >= *timeo) {
1408		int error = fxn(sdp->sd_vfs, 0);
1409		quotad_error(sdp, msg, error);
1410		*timeo = gfs2_tune_get_i(&sdp->sd_tune, new_timeo) * HZ;
1411	} else {
1412		*timeo -= t;
1413	}
1414}
1415
1416static void quotad_check_trunc_list(struct gfs2_sbd *sdp)
1417{
1418	struct gfs2_inode *ip;
1419
1420	while(1) {
1421		ip = NULL;
1422		spin_lock(&sdp->sd_trunc_lock);
1423		if (!list_empty(&sdp->sd_trunc_list)) {
1424			ip = list_entry(sdp->sd_trunc_list.next,
1425					struct gfs2_inode, i_trunc_list);
1426			list_del_init(&ip->i_trunc_list);
1427		}
1428		spin_unlock(&sdp->sd_trunc_lock);
1429		if (ip == NULL)
1430			return;
1431		gfs2_glock_finish_truncate(ip);
1432	}
1433}
1434
1435void gfs2_wake_up_statfs(struct gfs2_sbd *sdp) {
1436	if (!sdp->sd_statfs_force_sync) {
1437		sdp->sd_statfs_force_sync = 1;
1438		wake_up(&sdp->sd_quota_wait);
1439	}
1440}
1441
1442
1443/**
1444 * gfs2_quotad - Write cached quota changes into the quota file
1445 * @sdp: Pointer to GFS2 superblock
1446 *
1447 */
1448
1449int gfs2_quotad(void *data)
1450{
1451	struct gfs2_sbd *sdp = data;
1452	struct gfs2_tune *tune = &sdp->sd_tune;
1453	unsigned long statfs_timeo = 0;
1454	unsigned long quotad_timeo = 0;
1455	unsigned long t = 0;
1456	DEFINE_WAIT(wait);
1457	int empty;
1458
1459	while (!kthread_should_stop()) {
1460
1461		/* Update the master statfs file */
1462		if (sdp->sd_statfs_force_sync) {
1463			int error = gfs2_statfs_sync(sdp->sd_vfs, 0);
1464			quotad_error(sdp, "statfs", error);
1465			statfs_timeo = gfs2_tune_get(sdp, gt_statfs_quantum) * HZ;
1466		}
1467		else
1468			quotad_check_timeo(sdp, "statfs", gfs2_statfs_sync, t,
1469				   	   &statfs_timeo,
1470					   &tune->gt_statfs_quantum);
1471
1472		/* Update quota file */
1473		quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
1474				   &quotad_timeo, &tune->gt_quota_quantum);
1475
1476		/* Check for & recover partially truncated inodes */
1477		quotad_check_trunc_list(sdp);
1478
1479		try_to_freeze();
1480
1481		t = min(quotad_timeo, statfs_timeo);
1482
1483		prepare_to_wait(&sdp->sd_quota_wait, &wait, TASK_INTERRUPTIBLE);
1484		spin_lock(&sdp->sd_trunc_lock);
1485		empty = list_empty(&sdp->sd_trunc_list);
1486		spin_unlock(&sdp->sd_trunc_lock);
1487		if (empty && !sdp->sd_statfs_force_sync)
1488			t -= schedule_timeout(t);
1489		else
1490			t = 0;
1491		finish_wait(&sdp->sd_quota_wait, &wait);
1492	}
1493
1494	return 0;
1495}
1496
1497static int gfs2_quota_get_state(struct super_block *sb, struct qc_state *state)
1498{
1499	struct gfs2_sbd *sdp = sb->s_fs_info;
1500
1501	memset(state, 0, sizeof(*state));
1502
1503	switch (sdp->sd_args.ar_quota) {
1504	case GFS2_QUOTA_ON:
1505		state->s_state[USRQUOTA].flags |= QCI_LIMITS_ENFORCED;
1506		state->s_state[GRPQUOTA].flags |= QCI_LIMITS_ENFORCED;
1507		/*FALLTHRU*/
1508	case GFS2_QUOTA_ACCOUNT:
1509		state->s_state[USRQUOTA].flags |= QCI_ACCT_ENABLED |
1510						  QCI_SYSFILE;
1511		state->s_state[GRPQUOTA].flags |= QCI_ACCT_ENABLED |
1512						  QCI_SYSFILE;
1513		break;
1514	case GFS2_QUOTA_OFF:
1515		break;
1516	}
1517	if (sdp->sd_quota_inode) {
1518		state->s_state[USRQUOTA].ino =
1519					GFS2_I(sdp->sd_quota_inode)->i_no_addr;
1520		state->s_state[USRQUOTA].blocks = sdp->sd_quota_inode->i_blocks;
1521	}
1522	state->s_state[USRQUOTA].nextents = 1;	/* unsupported */
1523	state->s_state[GRPQUOTA] = state->s_state[USRQUOTA];
1524	state->s_incoredqs = list_lru_count(&gfs2_qd_lru);
1525	return 0;
1526}
1527
1528static int gfs2_get_dqblk(struct super_block *sb, struct kqid qid,
1529			  struct qc_dqblk *fdq)
1530{
1531	struct gfs2_sbd *sdp = sb->s_fs_info;
1532	struct gfs2_quota_lvb *qlvb;
1533	struct gfs2_quota_data *qd;
1534	struct gfs2_holder q_gh;
1535	int error;
1536
1537	memset(fdq, 0, sizeof(*fdq));
1538
1539	if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1540		return -ESRCH; /* Crazy XFS error code */
1541
1542	if ((qid.type != USRQUOTA) &&
1543	    (qid.type != GRPQUOTA))
1544		return -EINVAL;
1545
1546	error = qd_get(sdp, qid, &qd);
1547	if (error)
1548		return error;
1549	error = do_glock(qd, FORCE, &q_gh);
1550	if (error)
1551		goto out;
1552
1553	qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lksb.sb_lvbptr;
1554	fdq->d_spc_hardlimit = be64_to_cpu(qlvb->qb_limit) << sdp->sd_sb.sb_bsize_shift;
1555	fdq->d_spc_softlimit = be64_to_cpu(qlvb->qb_warn) << sdp->sd_sb.sb_bsize_shift;
1556	fdq->d_space = be64_to_cpu(qlvb->qb_value) << sdp->sd_sb.sb_bsize_shift;
1557
1558	gfs2_glock_dq_uninit(&q_gh);
1559out:
1560	qd_put(qd);
1561	return error;
1562}
1563
1564/* GFS2 only supports a subset of the XFS fields */
1565#define GFS2_FIELDMASK (QC_SPC_SOFT|QC_SPC_HARD|QC_SPACE)
1566
1567static int gfs2_set_dqblk(struct super_block *sb, struct kqid qid,
1568			  struct qc_dqblk *fdq)
1569{
1570	struct gfs2_sbd *sdp = sb->s_fs_info;
1571	struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode);
1572	struct gfs2_quota_data *qd;
1573	struct gfs2_holder q_gh, i_gh;
1574	unsigned int data_blocks, ind_blocks;
1575	unsigned int blocks = 0;
1576	int alloc_required;
1577	loff_t offset;
1578	int error;
1579
1580	if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
1581		return -ESRCH; /* Crazy XFS error code */
1582
1583	if ((qid.type != USRQUOTA) &&
1584	    (qid.type != GRPQUOTA))
1585		return -EINVAL;
1586
1587	if (fdq->d_fieldmask & ~GFS2_FIELDMASK)
1588		return -EINVAL;
1589
1590	error = qd_get(sdp, qid, &qd);
1591	if (error)
1592		return error;
1593
1594	error = gfs2_rs_alloc(ip);
1595	if (error)
1596		goto out_put;
1597
1598	mutex_lock(&ip->i_inode.i_mutex);
1599	error = gfs2_glock_nq_init(qd->qd_gl, LM_ST_EXCLUSIVE, 0, &q_gh);
1600	if (error)
1601		goto out_unlockput;
1602	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1603	if (error)
1604		goto out_q;
1605
1606	/* Check for existing entry, if none then alloc new blocks */
1607	error = update_qd(sdp, qd);
1608	if (error)
1609		goto out_i;
1610
1611	/* If nothing has changed, this is a no-op */
1612	if ((fdq->d_fieldmask & QC_SPC_SOFT) &&
1613	    ((fdq->d_spc_softlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_warn)))
1614		fdq->d_fieldmask ^= QC_SPC_SOFT;
1615
1616	if ((fdq->d_fieldmask & QC_SPC_HARD) &&
1617	    ((fdq->d_spc_hardlimit >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_limit)))
1618		fdq->d_fieldmask ^= QC_SPC_HARD;
1619
1620	if ((fdq->d_fieldmask & QC_SPACE) &&
1621	    ((fdq->d_space >> sdp->sd_sb.sb_bsize_shift) == be64_to_cpu(qd->qd_qb.qb_value)))
1622		fdq->d_fieldmask ^= QC_SPACE;
1623
1624	if (fdq->d_fieldmask == 0)
1625		goto out_i;
1626
1627	offset = qd2offset(qd);
1628	alloc_required = gfs2_write_alloc_required(ip, offset, sizeof(struct gfs2_quota));
1629	if (gfs2_is_stuffed(ip))
1630		alloc_required = 1;
1631	if (alloc_required) {
1632		struct gfs2_alloc_parms ap = { .aflags = 0, };
1633		gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota),
1634				       &data_blocks, &ind_blocks);
1635		blocks = 1 + data_blocks + ind_blocks;
1636		ap.target = blocks;
1637		error = gfs2_inplace_reserve(ip, &ap);
1638		if (error)
1639			goto out_i;
1640		blocks += gfs2_rg_blocks(ip, blocks);
1641	}
1642
1643	/* Some quotas span block boundaries and can update two blocks,
1644	   adding an extra block to the transaction to handle such quotas */
1645	error = gfs2_trans_begin(sdp, blocks + RES_DINODE + 2, 0);
1646	if (error)
1647		goto out_release;
1648
1649	/* Apply changes */
1650	error = gfs2_adjust_quota(ip, offset, 0, qd, fdq);
1651
1652	gfs2_trans_end(sdp);
1653out_release:
1654	if (alloc_required)
1655		gfs2_inplace_release(ip);
1656out_i:
1657	gfs2_glock_dq_uninit(&i_gh);
1658out_q:
1659	gfs2_glock_dq_uninit(&q_gh);
1660out_unlockput:
1661	mutex_unlock(&ip->i_inode.i_mutex);
1662out_put:
1663	qd_put(qd);
1664	return error;
1665}
1666
1667const struct quotactl_ops gfs2_quotactl_ops = {
1668	.quota_sync     = gfs2_quota_sync,
1669	.get_state	= gfs2_quota_get_state,
1670	.get_dqblk	= gfs2_get_dqblk,
1671	.set_dqblk	= gfs2_set_dqblk,
1672};
1673
1674void __init gfs2_quota_hash_init(void)
1675{
1676	unsigned i;
1677
1678	for(i = 0; i < GFS2_QD_HASH_SIZE; i++)
1679		INIT_HLIST_BL_HEAD(&qd_hash_table[i]);
1680}
1681