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-rw-r--r--fs/quota/dquot.c2617
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diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
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1/*
2 * Implementation of the diskquota system for the LINUX operating system. QUOTA
3 * is implemented using the BSD system call interface as the means of
4 * communication with the user level. This file contains the generic routines
5 * called by the different filesystems on allocation of an inode or block.
6 * These routines take care of the administration needed to have a consistent
7 * diskquota tracking system. The ideas of both user and group quotas are based
8 * on the Melbourne quota system as used on BSD derived systems. The internal
9 * implementation is based on one of the several variants of the LINUX
10 * inode-subsystem with added complexity of the diskquota system.
11 *
12 * Author: Marco van Wieringen <mvw@planets.elm.net>
13 *
14 * Fixes: Dmitry Gorodchanin <pgmdsg@ibi.com>, 11 Feb 96
15 *
16 * Revised list management to avoid races
17 * -- Bill Hawes, <whawes@star.net>, 9/98
18 *
19 * Fixed races in dquot_transfer(), dqget() and dquot_alloc_...().
20 * As the consequence the locking was moved from dquot_decr_...(),
21 * dquot_incr_...() to calling functions.
22 * invalidate_dquots() now writes modified dquots.
23 * Serialized quota_off() and quota_on() for mount point.
24 * Fixed a few bugs in grow_dquots().
25 * Fixed deadlock in write_dquot() - we no longer account quotas on
26 * quota files
27 * remove_dquot_ref() moved to inode.c - it now traverses through inodes
28 * add_dquot_ref() restarts after blocking
29 * Added check for bogus uid and fixed check for group in quotactl.
30 * Jan Kara, <jack@suse.cz>, sponsored by SuSE CR, 10-11/99
31 *
32 * Used struct list_head instead of own list struct
33 * Invalidation of referenced dquots is no longer possible
34 * Improved free_dquots list management
35 * Quota and i_blocks are now updated in one place to avoid races
36 * Warnings are now delayed so we won't block in critical section
37 * Write updated not to require dquot lock
38 * Jan Kara, <jack@suse.cz>, 9/2000
39 *
40 * Added dynamic quota structure allocation
41 * Jan Kara <jack@suse.cz> 12/2000
42 *
43 * Rewritten quota interface. Implemented new quota format and
44 * formats registering.
45 * Jan Kara, <jack@suse.cz>, 2001,2002
46 *
47 * New SMP locking.
48 * Jan Kara, <jack@suse.cz>, 10/2002
49 *
50 * Added journalled quota support, fix lock inversion problems
51 * Jan Kara, <jack@suse.cz>, 2003,2004
52 *
53 * (C) Copyright 1994 - 1997 Marco van Wieringen
54 */
55
56#include <linux/errno.h>
57#include <linux/kernel.h>
58#include <linux/fs.h>
59#include <linux/mount.h>
60#include <linux/mm.h>
61#include <linux/time.h>
62#include <linux/types.h>
63#include <linux/string.h>
64#include <linux/fcntl.h>
65#include <linux/stat.h>
66#include <linux/tty.h>
67#include <linux/file.h>
68#include <linux/slab.h>
69#include <linux/sysctl.h>
70#include <linux/init.h>
71#include <linux/module.h>
72#include <linux/proc_fs.h>
73#include <linux/security.h>
74#include <linux/kmod.h>
75#include <linux/namei.h>
76#include <linux/buffer_head.h>
77#include <linux/capability.h>
78#include <linux/quotaops.h>
79#include <linux/writeback.h> /* for inode_lock, oddly enough.. */
80#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
81#include <net/netlink.h>
82#include <net/genetlink.h>
83#endif
84
85#include <asm/uaccess.h>
86
87#define __DQUOT_PARANOIA
88
89/*
90 * There are three quota SMP locks. dq_list_lock protects all lists with quotas
91 * and quota formats, dqstats structure containing statistics about the lists
92 * dq_data_lock protects data from dq_dqb and also mem_dqinfo structures and
93 * also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes.
94 * i_blocks and i_bytes updates itself are guarded by i_lock acquired directly
95 * in inode_add_bytes() and inode_sub_bytes(). dq_state_lock protects
96 * modifications of quota state (on quotaon and quotaoff) and readers who care
97 * about latest values take it as well.
98 *
99 * The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock,
100 * dq_list_lock > dq_state_lock
101 *
102 * Note that some things (eg. sb pointer, type, id) doesn't change during
103 * the life of the dquot structure and so needn't to be protected by a lock
104 *
105 * Any operation working on dquots via inode pointers must hold dqptr_sem. If
106 * operation is just reading pointers from inode (or not using them at all) the
107 * read lock is enough. If pointers are altered function must hold write lock
108 * (these locking rules also apply for S_NOQUOTA flag in the inode - note that
109 * for altering the flag i_mutex is also needed).
110 *
111 * Each dquot has its dq_lock mutex. Locked dquots might not be referenced
112 * from inodes (dquot_alloc_space() and such don't check the dq_lock).
113 * Currently dquot is locked only when it is being read to memory (or space for
114 * it is being allocated) on the first dqget() and when it is being released on
115 * the last dqput(). The allocation and release oparations are serialized by
116 * the dq_lock and by checking the use count in dquot_release(). Write
117 * operations on dquots don't hold dq_lock as they copy data under dq_data_lock
118 * spinlock to internal buffers before writing.
119 *
120 * Lock ordering (including related VFS locks) is the following:
121 * i_mutex > dqonoff_sem > journal_lock > dqptr_sem > dquot->dq_lock >
122 * dqio_mutex
123 * The lock ordering of dqptr_sem imposed by quota code is only dqonoff_sem >
124 * dqptr_sem. But filesystem has to count with the fact that functions such as
125 * dquot_alloc_space() acquire dqptr_sem and they usually have to be called
126 * from inside a transaction to keep filesystem consistency after a crash. Also
127 * filesystems usually want to do some IO on dquot from ->mark_dirty which is
128 * called with dqptr_sem held.
129 * i_mutex on quota files is special (it's below dqio_mutex)
130 */
131
132static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_list_lock);
133static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_state_lock);
134__cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_data_lock);
135EXPORT_SYMBOL(dq_data_lock);
136
137static char *quotatypes[] = INITQFNAMES;
138static struct quota_format_type *quota_formats; /* List of registered formats */
139static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES;
140
141/* SLAB cache for dquot structures */
142static struct kmem_cache *dquot_cachep;
143
144int register_quota_format(struct quota_format_type *fmt)
145{
146 spin_lock(&dq_list_lock);
147 fmt->qf_next = quota_formats;
148 quota_formats = fmt;
149 spin_unlock(&dq_list_lock);
150 return 0;
151}
152EXPORT_SYMBOL(register_quota_format);
153
154void unregister_quota_format(struct quota_format_type *fmt)
155{
156 struct quota_format_type **actqf;
157
158 spin_lock(&dq_list_lock);
159 for (actqf = &quota_formats; *actqf && *actqf != fmt;
160 actqf = &(*actqf)->qf_next)
161 ;
162 if (*actqf)
163 *actqf = (*actqf)->qf_next;
164 spin_unlock(&dq_list_lock);
165}
166EXPORT_SYMBOL(unregister_quota_format);
167
168static struct quota_format_type *find_quota_format(int id)
169{
170 struct quota_format_type *actqf;
171
172 spin_lock(&dq_list_lock);
173 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id;
174 actqf = actqf->qf_next)
175 ;
176 if (!actqf || !try_module_get(actqf->qf_owner)) {
177 int qm;
178
179 spin_unlock(&dq_list_lock);
180
181 for (qm = 0; module_names[qm].qm_fmt_id &&
182 module_names[qm].qm_fmt_id != id; qm++)
183 ;
184 if (!module_names[qm].qm_fmt_id ||
185 request_module(module_names[qm].qm_mod_name))
186 return NULL;
187
188 spin_lock(&dq_list_lock);
189 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id;
190 actqf = actqf->qf_next)
191 ;
192 if (actqf && !try_module_get(actqf->qf_owner))
193 actqf = NULL;
194 }
195 spin_unlock(&dq_list_lock);
196 return actqf;
197}
198
199static void put_quota_format(struct quota_format_type *fmt)
200{
201 module_put(fmt->qf_owner);
202}
203
204/*
205 * Dquot List Management:
206 * The quota code uses three lists for dquot management: the inuse_list,
207 * free_dquots, and dquot_hash[] array. A single dquot structure may be
208 * on all three lists, depending on its current state.
209 *
210 * All dquots are placed to the end of inuse_list when first created, and this
211 * list is used for invalidate operation, which must look at every dquot.
212 *
213 * Unused dquots (dq_count == 0) are added to the free_dquots list when freed,
214 * and this list is searched whenever we need an available dquot. Dquots are
215 * removed from the list as soon as they are used again, and
216 * dqstats.free_dquots gives the number of dquots on the list. When
217 * dquot is invalidated it's completely released from memory.
218 *
219 * Dquots with a specific identity (device, type and id) are placed on
220 * one of the dquot_hash[] hash chains. The provides an efficient search
221 * mechanism to locate a specific dquot.
222 */
223
224static LIST_HEAD(inuse_list);
225static LIST_HEAD(free_dquots);
226static unsigned int dq_hash_bits, dq_hash_mask;
227static struct hlist_head *dquot_hash;
228
229struct dqstats dqstats;
230EXPORT_SYMBOL(dqstats);
231
232static inline unsigned int
233hashfn(const struct super_block *sb, unsigned int id, int type)
234{
235 unsigned long tmp;
236
237 tmp = (((unsigned long)sb>>L1_CACHE_SHIFT) ^ id) * (MAXQUOTAS - type);
238 return (tmp + (tmp >> dq_hash_bits)) & dq_hash_mask;
239}
240
241/*
242 * Following list functions expect dq_list_lock to be held
243 */
244static inline void insert_dquot_hash(struct dquot *dquot)
245{
246 struct hlist_head *head;
247 head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id, dquot->dq_type);
248 hlist_add_head(&dquot->dq_hash, head);
249}
250
251static inline void remove_dquot_hash(struct dquot *dquot)
252{
253 hlist_del_init(&dquot->dq_hash);
254}
255
256static struct dquot *find_dquot(unsigned int hashent, struct super_block *sb,
257 unsigned int id, int type)
258{
259 struct hlist_node *node;
260 struct dquot *dquot;
261
262 hlist_for_each (node, dquot_hash+hashent) {
263 dquot = hlist_entry(node, struct dquot, dq_hash);
264 if (dquot->dq_sb == sb && dquot->dq_id == id &&
265 dquot->dq_type == type)
266 return dquot;
267 }
268 return NULL;
269}
270
271/* Add a dquot to the tail of the free list */
272static inline void put_dquot_last(struct dquot *dquot)
273{
274 list_add_tail(&dquot->dq_free, &free_dquots);
275 dqstats.free_dquots++;
276}
277
278static inline void remove_free_dquot(struct dquot *dquot)
279{
280 if (list_empty(&dquot->dq_free))
281 return;
282 list_del_init(&dquot->dq_free);
283 dqstats.free_dquots--;
284}
285
286static inline void put_inuse(struct dquot *dquot)
287{
288 /* We add to the back of inuse list so we don't have to restart
289 * when traversing this list and we block */
290 list_add_tail(&dquot->dq_inuse, &inuse_list);
291 dqstats.allocated_dquots++;
292}
293
294static inline void remove_inuse(struct dquot *dquot)
295{
296 dqstats.allocated_dquots--;
297 list_del(&dquot->dq_inuse);
298}
299/*
300 * End of list functions needing dq_list_lock
301 */
302
303static void wait_on_dquot(struct dquot *dquot)
304{
305 mutex_lock(&dquot->dq_lock);
306 mutex_unlock(&dquot->dq_lock);
307}
308
309static inline int dquot_dirty(struct dquot *dquot)
310{
311 return test_bit(DQ_MOD_B, &dquot->dq_flags);
312}
313
314static inline int mark_dquot_dirty(struct dquot *dquot)
315{
316 return dquot->dq_sb->dq_op->mark_dirty(dquot);
317}
318
319int dquot_mark_dquot_dirty(struct dquot *dquot)
320{
321 spin_lock(&dq_list_lock);
322 if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags))
323 list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)->
324 info[dquot->dq_type].dqi_dirty_list);
325 spin_unlock(&dq_list_lock);
326 return 0;
327}
328EXPORT_SYMBOL(dquot_mark_dquot_dirty);
329
330/* This function needs dq_list_lock */
331static inline int clear_dquot_dirty(struct dquot *dquot)
332{
333 if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags))
334 return 0;
335 list_del_init(&dquot->dq_dirty);
336 return 1;
337}
338
339void mark_info_dirty(struct super_block *sb, int type)
340{
341 set_bit(DQF_INFO_DIRTY_B, &sb_dqopt(sb)->info[type].dqi_flags);
342}
343EXPORT_SYMBOL(mark_info_dirty);
344
345/*
346 * Read dquot from disk and alloc space for it
347 */
348
349int dquot_acquire(struct dquot *dquot)
350{
351 int ret = 0, ret2 = 0;
352 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
353
354 mutex_lock(&dquot->dq_lock);
355 mutex_lock(&dqopt->dqio_mutex);
356 if (!test_bit(DQ_READ_B, &dquot->dq_flags))
357 ret = dqopt->ops[dquot->dq_type]->read_dqblk(dquot);
358 if (ret < 0)
359 goto out_iolock;
360 set_bit(DQ_READ_B, &dquot->dq_flags);
361 /* Instantiate dquot if needed */
362 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) {
363 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot);
364 /* Write the info if needed */
365 if (info_dirty(&dqopt->info[dquot->dq_type])) {
366 ret2 = dqopt->ops[dquot->dq_type]->write_file_info(
367 dquot->dq_sb, dquot->dq_type);
368 }
369 if (ret < 0)
370 goto out_iolock;
371 if (ret2 < 0) {
372 ret = ret2;
373 goto out_iolock;
374 }
375 }
376 set_bit(DQ_ACTIVE_B, &dquot->dq_flags);
377out_iolock:
378 mutex_unlock(&dqopt->dqio_mutex);
379 mutex_unlock(&dquot->dq_lock);
380 return ret;
381}
382EXPORT_SYMBOL(dquot_acquire);
383
384/*
385 * Write dquot to disk
386 */
387int dquot_commit(struct dquot *dquot)
388{
389 int ret = 0, ret2 = 0;
390 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
391
392 mutex_lock(&dqopt->dqio_mutex);
393 spin_lock(&dq_list_lock);
394 if (!clear_dquot_dirty(dquot)) {
395 spin_unlock(&dq_list_lock);
396 goto out_sem;
397 }
398 spin_unlock(&dq_list_lock);
399 /* Inactive dquot can be only if there was error during read/init
400 * => we have better not writing it */
401 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
402 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot);
403 if (info_dirty(&dqopt->info[dquot->dq_type])) {
404 ret2 = dqopt->ops[dquot->dq_type]->write_file_info(
405 dquot->dq_sb, dquot->dq_type);
406 }
407 if (ret >= 0)
408 ret = ret2;
409 }
410out_sem:
411 mutex_unlock(&dqopt->dqio_mutex);
412 return ret;
413}
414EXPORT_SYMBOL(dquot_commit);
415
416/*
417 * Release dquot
418 */
419int dquot_release(struct dquot *dquot)
420{
421 int ret = 0, ret2 = 0;
422 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
423
424 mutex_lock(&dquot->dq_lock);
425 /* Check whether we are not racing with some other dqget() */
426 if (atomic_read(&dquot->dq_count) > 1)
427 goto out_dqlock;
428 mutex_lock(&dqopt->dqio_mutex);
429 if (dqopt->ops[dquot->dq_type]->release_dqblk) {
430 ret = dqopt->ops[dquot->dq_type]->release_dqblk(dquot);
431 /* Write the info */
432 if (info_dirty(&dqopt->info[dquot->dq_type])) {
433 ret2 = dqopt->ops[dquot->dq_type]->write_file_info(
434 dquot->dq_sb, dquot->dq_type);
435 }
436 if (ret >= 0)
437 ret = ret2;
438 }
439 clear_bit(DQ_ACTIVE_B, &dquot->dq_flags);
440 mutex_unlock(&dqopt->dqio_mutex);
441out_dqlock:
442 mutex_unlock(&dquot->dq_lock);
443 return ret;
444}
445EXPORT_SYMBOL(dquot_release);
446
447void dquot_destroy(struct dquot *dquot)
448{
449 kmem_cache_free(dquot_cachep, dquot);
450}
451EXPORT_SYMBOL(dquot_destroy);
452
453static inline void do_destroy_dquot(struct dquot *dquot)
454{
455 dquot->dq_sb->dq_op->destroy_dquot(dquot);
456}
457
458/* Invalidate all dquots on the list. Note that this function is called after
459 * quota is disabled and pointers from inodes removed so there cannot be new
460 * quota users. There can still be some users of quotas due to inodes being
461 * just deleted or pruned by prune_icache() (those are not attached to any
462 * list) or parallel quotactl call. We have to wait for such users.
463 */
464static void invalidate_dquots(struct super_block *sb, int type)
465{
466 struct dquot *dquot, *tmp;
467
468restart:
469 spin_lock(&dq_list_lock);
470 list_for_each_entry_safe(dquot, tmp, &inuse_list, dq_inuse) {
471 if (dquot->dq_sb != sb)
472 continue;
473 if (dquot->dq_type != type)
474 continue;
475 /* Wait for dquot users */
476 if (atomic_read(&dquot->dq_count)) {
477 DEFINE_WAIT(wait);
478
479 atomic_inc(&dquot->dq_count);
480 prepare_to_wait(&dquot->dq_wait_unused, &wait,
481 TASK_UNINTERRUPTIBLE);
482 spin_unlock(&dq_list_lock);
483 /* Once dqput() wakes us up, we know it's time to free
484 * the dquot.
485 * IMPORTANT: we rely on the fact that there is always
486 * at most one process waiting for dquot to free.
487 * Otherwise dq_count would be > 1 and we would never
488 * wake up.
489 */
490 if (atomic_read(&dquot->dq_count) > 1)
491 schedule();
492 finish_wait(&dquot->dq_wait_unused, &wait);
493 dqput(dquot);
494 /* At this moment dquot() need not exist (it could be
495 * reclaimed by prune_dqcache(). Hence we must
496 * restart. */
497 goto restart;
498 }
499 /*
500 * Quota now has no users and it has been written on last
501 * dqput()
502 */
503 remove_dquot_hash(dquot);
504 remove_free_dquot(dquot);
505 remove_inuse(dquot);
506 do_destroy_dquot(dquot);
507 }
508 spin_unlock(&dq_list_lock);
509}
510
511/* Call callback for every active dquot on given filesystem */
512int dquot_scan_active(struct super_block *sb,
513 int (*fn)(struct dquot *dquot, unsigned long priv),
514 unsigned long priv)
515{
516 struct dquot *dquot, *old_dquot = NULL;
517 int ret = 0;
518
519 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
520 spin_lock(&dq_list_lock);
521 list_for_each_entry(dquot, &inuse_list, dq_inuse) {
522 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags))
523 continue;
524 if (dquot->dq_sb != sb)
525 continue;
526 /* Now we have active dquot so we can just increase use count */
527 atomic_inc(&dquot->dq_count);
528 dqstats.lookups++;
529 spin_unlock(&dq_list_lock);
530 dqput(old_dquot);
531 old_dquot = dquot;
532 ret = fn(dquot, priv);
533 if (ret < 0)
534 goto out;
535 spin_lock(&dq_list_lock);
536 /* We are safe to continue now because our dquot could not
537 * be moved out of the inuse list while we hold the reference */
538 }
539 spin_unlock(&dq_list_lock);
540out:
541 dqput(old_dquot);
542 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
543 return ret;
544}
545EXPORT_SYMBOL(dquot_scan_active);
546
547int vfs_quota_sync(struct super_block *sb, int type)
548{
549 struct list_head *dirty;
550 struct dquot *dquot;
551 struct quota_info *dqopt = sb_dqopt(sb);
552 int cnt;
553
554 mutex_lock(&dqopt->dqonoff_mutex);
555 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
556 if (type != -1 && cnt != type)
557 continue;
558 if (!sb_has_quota_active(sb, cnt))
559 continue;
560 spin_lock(&dq_list_lock);
561 dirty = &dqopt->info[cnt].dqi_dirty_list;
562 while (!list_empty(dirty)) {
563 dquot = list_first_entry(dirty, struct dquot,
564 dq_dirty);
565 /* Dirty and inactive can be only bad dquot... */
566 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
567 clear_dquot_dirty(dquot);
568 continue;
569 }
570 /* Now we have active dquot from which someone is
571 * holding reference so we can safely just increase
572 * use count */
573 atomic_inc(&dquot->dq_count);
574 dqstats.lookups++;
575 spin_unlock(&dq_list_lock);
576 sb->dq_op->write_dquot(dquot);
577 dqput(dquot);
578 spin_lock(&dq_list_lock);
579 }
580 spin_unlock(&dq_list_lock);
581 }
582
583 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
584 if ((cnt == type || type == -1) && sb_has_quota_active(sb, cnt)
585 && info_dirty(&dqopt->info[cnt]))
586 sb->dq_op->write_info(sb, cnt);
587 spin_lock(&dq_list_lock);
588 dqstats.syncs++;
589 spin_unlock(&dq_list_lock);
590 mutex_unlock(&dqopt->dqonoff_mutex);
591
592 return 0;
593}
594EXPORT_SYMBOL(vfs_quota_sync);
595
596/* Free unused dquots from cache */
597static void prune_dqcache(int count)
598{
599 struct list_head *head;
600 struct dquot *dquot;
601
602 head = free_dquots.prev;
603 while (head != &free_dquots && count) {
604 dquot = list_entry(head, struct dquot, dq_free);
605 remove_dquot_hash(dquot);
606 remove_free_dquot(dquot);
607 remove_inuse(dquot);
608 do_destroy_dquot(dquot);
609 count--;
610 head = free_dquots.prev;
611 }
612}
613
614/*
615 * This is called from kswapd when we think we need some
616 * more memory
617 */
618
619static int shrink_dqcache_memory(int nr, gfp_t gfp_mask)
620{
621 if (nr) {
622 spin_lock(&dq_list_lock);
623 prune_dqcache(nr);
624 spin_unlock(&dq_list_lock);
625 }
626 return (dqstats.free_dquots / 100) * sysctl_vfs_cache_pressure;
627}
628
629static struct shrinker dqcache_shrinker = {
630 .shrink = shrink_dqcache_memory,
631 .seeks = DEFAULT_SEEKS,
632};
633
634/*
635 * Put reference to dquot
636 * NOTE: If you change this function please check whether dqput_blocks() works right...
637 */
638void dqput(struct dquot *dquot)
639{
640 int ret;
641
642 if (!dquot)
643 return;
644#ifdef __DQUOT_PARANOIA
645 if (!atomic_read(&dquot->dq_count)) {
646 printk("VFS: dqput: trying to free free dquot\n");
647 printk("VFS: device %s, dquot of %s %d\n",
648 dquot->dq_sb->s_id,
649 quotatypes[dquot->dq_type],
650 dquot->dq_id);
651 BUG();
652 }
653#endif
654
655 spin_lock(&dq_list_lock);
656 dqstats.drops++;
657 spin_unlock(&dq_list_lock);
658we_slept:
659 spin_lock(&dq_list_lock);
660 if (atomic_read(&dquot->dq_count) > 1) {
661 /* We have more than one user... nothing to do */
662 atomic_dec(&dquot->dq_count);
663 /* Releasing dquot during quotaoff phase? */
664 if (!sb_has_quota_active(dquot->dq_sb, dquot->dq_type) &&
665 atomic_read(&dquot->dq_count) == 1)
666 wake_up(&dquot->dq_wait_unused);
667 spin_unlock(&dq_list_lock);
668 return;
669 }
670 /* Need to release dquot? */
671 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) {
672 spin_unlock(&dq_list_lock);
673 /* Commit dquot before releasing */
674 ret = dquot->dq_sb->dq_op->write_dquot(dquot);
675 if (ret < 0) {
676 printk(KERN_ERR "VFS: cannot write quota structure on "
677 "device %s (error %d). Quota may get out of "
678 "sync!\n", dquot->dq_sb->s_id, ret);
679 /*
680 * We clear dirty bit anyway, so that we avoid
681 * infinite loop here
682 */
683 spin_lock(&dq_list_lock);
684 clear_dquot_dirty(dquot);
685 spin_unlock(&dq_list_lock);
686 }
687 goto we_slept;
688 }
689 /* Clear flag in case dquot was inactive (something bad happened) */
690 clear_dquot_dirty(dquot);
691 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
692 spin_unlock(&dq_list_lock);
693 dquot->dq_sb->dq_op->release_dquot(dquot);
694 goto we_slept;
695 }
696 atomic_dec(&dquot->dq_count);
697#ifdef __DQUOT_PARANOIA
698 /* sanity check */
699 BUG_ON(!list_empty(&dquot->dq_free));
700#endif
701 put_dquot_last(dquot);
702 spin_unlock(&dq_list_lock);
703}
704EXPORT_SYMBOL(dqput);
705
706struct dquot *dquot_alloc(struct super_block *sb, int type)
707{
708 return kmem_cache_zalloc(dquot_cachep, GFP_NOFS);
709}
710EXPORT_SYMBOL(dquot_alloc);
711
712static struct dquot *get_empty_dquot(struct super_block *sb, int type)
713{
714 struct dquot *dquot;
715
716 dquot = sb->dq_op->alloc_dquot(sb, type);
717 if(!dquot)
718 return NULL;
719
720 mutex_init(&dquot->dq_lock);
721 INIT_LIST_HEAD(&dquot->dq_free);
722 INIT_LIST_HEAD(&dquot->dq_inuse);
723 INIT_HLIST_NODE(&dquot->dq_hash);
724 INIT_LIST_HEAD(&dquot->dq_dirty);
725 init_waitqueue_head(&dquot->dq_wait_unused);
726 dquot->dq_sb = sb;
727 dquot->dq_type = type;
728 atomic_set(&dquot->dq_count, 1);
729
730 return dquot;
731}
732
733/*
734 * Get reference to dquot
735 *
736 * Locking is slightly tricky here. We are guarded from parallel quotaoff()
737 * destroying our dquot by:
738 * a) checking for quota flags under dq_list_lock and
739 * b) getting a reference to dquot before we release dq_list_lock
740 */
741struct dquot *dqget(struct super_block *sb, unsigned int id, int type)
742{
743 unsigned int hashent = hashfn(sb, id, type);
744 struct dquot *dquot = NULL, *empty = NULL;
745
746 if (!sb_has_quota_active(sb, type))
747 return NULL;
748we_slept:
749 spin_lock(&dq_list_lock);
750 spin_lock(&dq_state_lock);
751 if (!sb_has_quota_active(sb, type)) {
752 spin_unlock(&dq_state_lock);
753 spin_unlock(&dq_list_lock);
754 goto out;
755 }
756 spin_unlock(&dq_state_lock);
757
758 dquot = find_dquot(hashent, sb, id, type);
759 if (!dquot) {
760 if (!empty) {
761 spin_unlock(&dq_list_lock);
762 empty = get_empty_dquot(sb, type);
763 if (!empty)
764 schedule(); /* Try to wait for a moment... */
765 goto we_slept;
766 }
767 dquot = empty;
768 empty = NULL;
769 dquot->dq_id = id;
770 /* all dquots go on the inuse_list */
771 put_inuse(dquot);
772 /* hash it first so it can be found */
773 insert_dquot_hash(dquot);
774 dqstats.lookups++;
775 spin_unlock(&dq_list_lock);
776 } else {
777 if (!atomic_read(&dquot->dq_count))
778 remove_free_dquot(dquot);
779 atomic_inc(&dquot->dq_count);
780 dqstats.cache_hits++;
781 dqstats.lookups++;
782 spin_unlock(&dq_list_lock);
783 }
784 /* Wait for dq_lock - after this we know that either dquot_release() is
785 * already finished or it will be canceled due to dq_count > 1 test */
786 wait_on_dquot(dquot);
787 /* Read the dquot / allocate space in quota file */
788 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) &&
789 sb->dq_op->acquire_dquot(dquot) < 0) {
790 dqput(dquot);
791 dquot = NULL;
792 goto out;
793 }
794#ifdef __DQUOT_PARANOIA
795 BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */
796#endif
797out:
798 if (empty)
799 do_destroy_dquot(empty);
800
801 return dquot;
802}
803EXPORT_SYMBOL(dqget);
804
805static int dqinit_needed(struct inode *inode, int type)
806{
807 int cnt;
808
809 if (IS_NOQUOTA(inode))
810 return 0;
811 if (type != -1)
812 return !inode->i_dquot[type];
813 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
814 if (!inode->i_dquot[cnt])
815 return 1;
816 return 0;
817}
818
819/* This routine is guarded by dqonoff_mutex mutex */
820static void add_dquot_ref(struct super_block *sb, int type)
821{
822 struct inode *inode, *old_inode = NULL;
823
824 spin_lock(&inode_lock);
825 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
826 if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW))
827 continue;
828 if (!atomic_read(&inode->i_writecount))
829 continue;
830 if (!dqinit_needed(inode, type))
831 continue;
832
833 __iget(inode);
834 spin_unlock(&inode_lock);
835
836 iput(old_inode);
837 sb->dq_op->initialize(inode, type);
838 /* We hold a reference to 'inode' so it couldn't have been
839 * removed from s_inodes list while we dropped the inode_lock.
840 * We cannot iput the inode now as we can be holding the last
841 * reference and we cannot iput it under inode_lock. So we
842 * keep the reference and iput it later. */
843 old_inode = inode;
844 spin_lock(&inode_lock);
845 }
846 spin_unlock(&inode_lock);
847 iput(old_inode);
848}
849
850/*
851 * Return 0 if dqput() won't block.
852 * (note that 1 doesn't necessarily mean blocking)
853 */
854static inline int dqput_blocks(struct dquot *dquot)
855{
856 if (atomic_read(&dquot->dq_count) <= 1)
857 return 1;
858 return 0;
859}
860
861/*
862 * Remove references to dquots from inode and add dquot to list for freeing
863 * if we have the last referece to dquot
864 * We can't race with anybody because we hold dqptr_sem for writing...
865 */
866static int remove_inode_dquot_ref(struct inode *inode, int type,
867 struct list_head *tofree_head)
868{
869 struct dquot *dquot = inode->i_dquot[type];
870
871 inode->i_dquot[type] = NULL;
872 if (dquot) {
873 if (dqput_blocks(dquot)) {
874#ifdef __DQUOT_PARANOIA
875 if (atomic_read(&dquot->dq_count) != 1)
876 printk(KERN_WARNING "VFS: Adding dquot with dq_count %d to dispose list.\n", atomic_read(&dquot->dq_count));
877#endif
878 spin_lock(&dq_list_lock);
879 /* As dquot must have currently users it can't be on
880 * the free list... */
881 list_add(&dquot->dq_free, tofree_head);
882 spin_unlock(&dq_list_lock);
883 return 1;
884 }
885 else
886 dqput(dquot); /* We have guaranteed we won't block */
887 }
888 return 0;
889}
890
891/*
892 * Free list of dquots
893 * Dquots are removed from inodes and no new references can be got so we are
894 * the only ones holding reference
895 */
896static void put_dquot_list(struct list_head *tofree_head)
897{
898 struct list_head *act_head;
899 struct dquot *dquot;
900
901 act_head = tofree_head->next;
902 while (act_head != tofree_head) {
903 dquot = list_entry(act_head, struct dquot, dq_free);
904 act_head = act_head->next;
905 /* Remove dquot from the list so we won't have problems... */
906 list_del_init(&dquot->dq_free);
907 dqput(dquot);
908 }
909}
910
911static void remove_dquot_ref(struct super_block *sb, int type,
912 struct list_head *tofree_head)
913{
914 struct inode *inode;
915
916 spin_lock(&inode_lock);
917 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
918 /*
919 * We have to scan also I_NEW inodes because they can already
920 * have quota pointer initialized. Luckily, we need to touch
921 * only quota pointers and these have separate locking
922 * (dqptr_sem).
923 */
924 if (!IS_NOQUOTA(inode))
925 remove_inode_dquot_ref(inode, type, tofree_head);
926 }
927 spin_unlock(&inode_lock);
928}
929
930/* Gather all references from inodes and drop them */
931static void drop_dquot_ref(struct super_block *sb, int type)
932{
933 LIST_HEAD(tofree_head);
934
935 if (sb->dq_op) {
936 down_write(&sb_dqopt(sb)->dqptr_sem);
937 remove_dquot_ref(sb, type, &tofree_head);
938 up_write(&sb_dqopt(sb)->dqptr_sem);
939 put_dquot_list(&tofree_head);
940 }
941}
942
943static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number)
944{
945 dquot->dq_dqb.dqb_curinodes += number;
946}
947
948static inline void dquot_incr_space(struct dquot *dquot, qsize_t number)
949{
950 dquot->dq_dqb.dqb_curspace += number;
951}
952
953static inline void dquot_resv_space(struct dquot *dquot, qsize_t number)
954{
955 dquot->dq_dqb.dqb_rsvspace += number;
956}
957
958/*
959 * Claim reserved quota space
960 */
961static void dquot_claim_reserved_space(struct dquot *dquot,
962 qsize_t number)
963{
964 WARN_ON(dquot->dq_dqb.dqb_rsvspace < number);
965 dquot->dq_dqb.dqb_curspace += number;
966 dquot->dq_dqb.dqb_rsvspace -= number;
967}
968
969static inline
970void dquot_free_reserved_space(struct dquot *dquot, qsize_t number)
971{
972 dquot->dq_dqb.dqb_rsvspace -= number;
973}
974
975static void dquot_decr_inodes(struct dquot *dquot, qsize_t number)
976{
977 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE ||
978 dquot->dq_dqb.dqb_curinodes >= number)
979 dquot->dq_dqb.dqb_curinodes -= number;
980 else
981 dquot->dq_dqb.dqb_curinodes = 0;
982 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit)
983 dquot->dq_dqb.dqb_itime = (time_t) 0;
984 clear_bit(DQ_INODES_B, &dquot->dq_flags);
985}
986
987static void dquot_decr_space(struct dquot *dquot, qsize_t number)
988{
989 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE ||
990 dquot->dq_dqb.dqb_curspace >= number)
991 dquot->dq_dqb.dqb_curspace -= number;
992 else
993 dquot->dq_dqb.dqb_curspace = 0;
994 if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit)
995 dquot->dq_dqb.dqb_btime = (time_t) 0;
996 clear_bit(DQ_BLKS_B, &dquot->dq_flags);
997}
998
999static int warning_issued(struct dquot *dquot, const int warntype)
1000{
1001 int flag = (warntype == QUOTA_NL_BHARDWARN ||
1002 warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B :
1003 ((warntype == QUOTA_NL_IHARDWARN ||
1004 warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0);
1005
1006 if (!flag)
1007 return 0;
1008 return test_and_set_bit(flag, &dquot->dq_flags);
1009}
1010
1011#ifdef CONFIG_PRINT_QUOTA_WARNING
1012static int flag_print_warnings = 1;
1013
1014static int need_print_warning(struct dquot *dquot)
1015{
1016 if (!flag_print_warnings)
1017 return 0;
1018
1019 switch (dquot->dq_type) {
1020 case USRQUOTA:
1021 return current_fsuid() == dquot->dq_id;
1022 case GRPQUOTA:
1023 return in_group_p(dquot->dq_id);
1024 }
1025 return 0;
1026}
1027
1028/* Print warning to user which exceeded quota */
1029static void print_warning(struct dquot *dquot, const int warntype)
1030{
1031 char *msg = NULL;
1032 struct tty_struct *tty;
1033
1034 if (warntype == QUOTA_NL_IHARDBELOW ||
1035 warntype == QUOTA_NL_ISOFTBELOW ||
1036 warntype == QUOTA_NL_BHARDBELOW ||
1037 warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(dquot))
1038 return;
1039
1040 tty = get_current_tty();
1041 if (!tty)
1042 return;
1043 tty_write_message(tty, dquot->dq_sb->s_id);
1044 if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN)
1045 tty_write_message(tty, ": warning, ");
1046 else
1047 tty_write_message(tty, ": write failed, ");
1048 tty_write_message(tty, quotatypes[dquot->dq_type]);
1049 switch (warntype) {
1050 case QUOTA_NL_IHARDWARN:
1051 msg = " file limit reached.\r\n";
1052 break;
1053 case QUOTA_NL_ISOFTLONGWARN:
1054 msg = " file quota exceeded too long.\r\n";
1055 break;
1056 case QUOTA_NL_ISOFTWARN:
1057 msg = " file quota exceeded.\r\n";
1058 break;
1059 case QUOTA_NL_BHARDWARN:
1060 msg = " block limit reached.\r\n";
1061 break;
1062 case QUOTA_NL_BSOFTLONGWARN:
1063 msg = " block quota exceeded too long.\r\n";
1064 break;
1065 case QUOTA_NL_BSOFTWARN:
1066 msg = " block quota exceeded.\r\n";
1067 break;
1068 }
1069 tty_write_message(tty, msg);
1070 tty_kref_put(tty);
1071}
1072#endif
1073
1074#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
1075
1076/* Netlink family structure for quota */
1077static struct genl_family quota_genl_family = {
1078 .id = GENL_ID_GENERATE,
1079 .hdrsize = 0,
1080 .name = "VFS_DQUOT",
1081 .version = 1,
1082 .maxattr = QUOTA_NL_A_MAX,
1083};
1084
1085/* Send warning to userspace about user which exceeded quota */
1086static void send_warning(const struct dquot *dquot, const char warntype)
1087{
1088 static atomic_t seq;
1089 struct sk_buff *skb;
1090 void *msg_head;
1091 int ret;
1092 int msg_size = 4 * nla_total_size(sizeof(u32)) +
1093 2 * nla_total_size(sizeof(u64));
1094
1095 /* We have to allocate using GFP_NOFS as we are called from a
1096 * filesystem performing write and thus further recursion into
1097 * the fs to free some data could cause deadlocks. */
1098 skb = genlmsg_new(msg_size, GFP_NOFS);
1099 if (!skb) {
1100 printk(KERN_ERR
1101 "VFS: Not enough memory to send quota warning.\n");
1102 return;
1103 }
1104 msg_head = genlmsg_put(skb, 0, atomic_add_return(1, &seq),
1105 &quota_genl_family, 0, QUOTA_NL_C_WARNING);
1106 if (!msg_head) {
1107 printk(KERN_ERR
1108 "VFS: Cannot store netlink header in quota warning.\n");
1109 goto err_out;
1110 }
1111 ret = nla_put_u32(skb, QUOTA_NL_A_QTYPE, dquot->dq_type);
1112 if (ret)
1113 goto attr_err_out;
1114 ret = nla_put_u64(skb, QUOTA_NL_A_EXCESS_ID, dquot->dq_id);
1115 if (ret)
1116 goto attr_err_out;
1117 ret = nla_put_u32(skb, QUOTA_NL_A_WARNING, warntype);
1118 if (ret)
1119 goto attr_err_out;
1120 ret = nla_put_u32(skb, QUOTA_NL_A_DEV_MAJOR,
1121 MAJOR(dquot->dq_sb->s_dev));
1122 if (ret)
1123 goto attr_err_out;
1124 ret = nla_put_u32(skb, QUOTA_NL_A_DEV_MINOR,
1125 MINOR(dquot->dq_sb->s_dev));
1126 if (ret)
1127 goto attr_err_out;
1128 ret = nla_put_u64(skb, QUOTA_NL_A_CAUSED_ID, current_uid());
1129 if (ret)
1130 goto attr_err_out;
1131 genlmsg_end(skb, msg_head);
1132
1133 genlmsg_multicast(skb, 0, quota_genl_family.id, GFP_NOFS);
1134 return;
1135attr_err_out:
1136 printk(KERN_ERR "VFS: Not enough space to compose quota message!\n");
1137err_out:
1138 kfree_skb(skb);
1139}
1140#endif
1141/*
1142 * Write warnings to the console and send warning messages over netlink.
1143 *
1144 * Note that this function can sleep.
1145 */
1146static void flush_warnings(struct dquot *const *dquots, char *warntype)
1147{
1148 int i;
1149
1150 for (i = 0; i < MAXQUOTAS; i++)
1151 if (dquots[i] && warntype[i] != QUOTA_NL_NOWARN &&
1152 !warning_issued(dquots[i], warntype[i])) {
1153#ifdef CONFIG_PRINT_QUOTA_WARNING
1154 print_warning(dquots[i], warntype[i]);
1155#endif
1156#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
1157 send_warning(dquots[i], warntype[i]);
1158#endif
1159 }
1160}
1161
1162static int ignore_hardlimit(struct dquot *dquot)
1163{
1164 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type];
1165
1166 return capable(CAP_SYS_RESOURCE) &&
1167 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD ||
1168 !(info->dqi_flags & V1_DQF_RSQUASH));
1169}
1170
1171/* needs dq_data_lock */
1172static int check_idq(struct dquot *dquot, qsize_t inodes, char *warntype)
1173{
1174 qsize_t newinodes = dquot->dq_dqb.dqb_curinodes + inodes;
1175
1176 *warntype = QUOTA_NL_NOWARN;
1177 if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type) ||
1178 test_bit(DQ_FAKE_B, &dquot->dq_flags))
1179 return QUOTA_OK;
1180
1181 if (dquot->dq_dqb.dqb_ihardlimit &&
1182 newinodes > dquot->dq_dqb.dqb_ihardlimit &&
1183 !ignore_hardlimit(dquot)) {
1184 *warntype = QUOTA_NL_IHARDWARN;
1185 return NO_QUOTA;
1186 }
1187
1188 if (dquot->dq_dqb.dqb_isoftlimit &&
1189 newinodes > dquot->dq_dqb.dqb_isoftlimit &&
1190 dquot->dq_dqb.dqb_itime &&
1191 get_seconds() >= dquot->dq_dqb.dqb_itime &&
1192 !ignore_hardlimit(dquot)) {
1193 *warntype = QUOTA_NL_ISOFTLONGWARN;
1194 return NO_QUOTA;
1195 }
1196
1197 if (dquot->dq_dqb.dqb_isoftlimit &&
1198 newinodes > dquot->dq_dqb.dqb_isoftlimit &&
1199 dquot->dq_dqb.dqb_itime == 0) {
1200 *warntype = QUOTA_NL_ISOFTWARN;
1201 dquot->dq_dqb.dqb_itime = get_seconds() +
1202 sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace;
1203 }
1204
1205 return QUOTA_OK;
1206}
1207
1208/* needs dq_data_lock */
1209static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype)
1210{
1211 qsize_t tspace;
1212 struct super_block *sb = dquot->dq_sb;
1213
1214 *warntype = QUOTA_NL_NOWARN;
1215 if (!sb_has_quota_limits_enabled(sb, dquot->dq_type) ||
1216 test_bit(DQ_FAKE_B, &dquot->dq_flags))
1217 return QUOTA_OK;
1218
1219 tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace
1220 + space;
1221
1222 if (dquot->dq_dqb.dqb_bhardlimit &&
1223 tspace > dquot->dq_dqb.dqb_bhardlimit &&
1224 !ignore_hardlimit(dquot)) {
1225 if (!prealloc)
1226 *warntype = QUOTA_NL_BHARDWARN;
1227 return NO_QUOTA;
1228 }
1229
1230 if (dquot->dq_dqb.dqb_bsoftlimit &&
1231 tspace > dquot->dq_dqb.dqb_bsoftlimit &&
1232 dquot->dq_dqb.dqb_btime &&
1233 get_seconds() >= dquot->dq_dqb.dqb_btime &&
1234 !ignore_hardlimit(dquot)) {
1235 if (!prealloc)
1236 *warntype = QUOTA_NL_BSOFTLONGWARN;
1237 return NO_QUOTA;
1238 }
1239
1240 if (dquot->dq_dqb.dqb_bsoftlimit &&
1241 tspace > dquot->dq_dqb.dqb_bsoftlimit &&
1242 dquot->dq_dqb.dqb_btime == 0) {
1243 if (!prealloc) {
1244 *warntype = QUOTA_NL_BSOFTWARN;
1245 dquot->dq_dqb.dqb_btime = get_seconds() +
1246 sb_dqopt(sb)->info[dquot->dq_type].dqi_bgrace;
1247 }
1248 else
1249 /*
1250 * We don't allow preallocation to exceed softlimit so exceeding will
1251 * be always printed
1252 */
1253 return NO_QUOTA;
1254 }
1255
1256 return QUOTA_OK;
1257}
1258
1259static int info_idq_free(struct dquot *dquot, qsize_t inodes)
1260{
1261 qsize_t newinodes;
1262
1263 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) ||
1264 dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit ||
1265 !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type))
1266 return QUOTA_NL_NOWARN;
1267
1268 newinodes = dquot->dq_dqb.dqb_curinodes - inodes;
1269 if (newinodes <= dquot->dq_dqb.dqb_isoftlimit)
1270 return QUOTA_NL_ISOFTBELOW;
1271 if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit &&
1272 newinodes < dquot->dq_dqb.dqb_ihardlimit)
1273 return QUOTA_NL_IHARDBELOW;
1274 return QUOTA_NL_NOWARN;
1275}
1276
1277static int info_bdq_free(struct dquot *dquot, qsize_t space)
1278{
1279 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) ||
1280 dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit)
1281 return QUOTA_NL_NOWARN;
1282
1283 if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit)
1284 return QUOTA_NL_BSOFTBELOW;
1285 if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit &&
1286 dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit)
1287 return QUOTA_NL_BHARDBELOW;
1288 return QUOTA_NL_NOWARN;
1289}
1290/*
1291 * Initialize quota pointers in inode
1292 * We do things in a bit complicated way but by that we avoid calling
1293 * dqget() and thus filesystem callbacks under dqptr_sem.
1294 */
1295int dquot_initialize(struct inode *inode, int type)
1296{
1297 unsigned int id = 0;
1298 int cnt, ret = 0;
1299 struct dquot *got[MAXQUOTAS] = { NULL, NULL };
1300 struct super_block *sb = inode->i_sb;
1301
1302 /* First test before acquiring mutex - solves deadlocks when we
1303 * re-enter the quota code and are already holding the mutex */
1304 if (IS_NOQUOTA(inode))
1305 return 0;
1306
1307 /* First get references to structures we might need. */
1308 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1309 if (type != -1 && cnt != type)
1310 continue;
1311 switch (cnt) {
1312 case USRQUOTA:
1313 id = inode->i_uid;
1314 break;
1315 case GRPQUOTA:
1316 id = inode->i_gid;
1317 break;
1318 }
1319 got[cnt] = dqget(sb, id, cnt);
1320 }
1321
1322 down_write(&sb_dqopt(sb)->dqptr_sem);
1323 /* Having dqptr_sem we know NOQUOTA flags can't be altered... */
1324 if (IS_NOQUOTA(inode))
1325 goto out_err;
1326 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1327 if (type != -1 && cnt != type)
1328 continue;
1329 /* Avoid races with quotaoff() */
1330 if (!sb_has_quota_active(sb, cnt))
1331 continue;
1332 if (!inode->i_dquot[cnt]) {
1333 inode->i_dquot[cnt] = got[cnt];
1334 got[cnt] = NULL;
1335 }
1336 }
1337out_err:
1338 up_write(&sb_dqopt(sb)->dqptr_sem);
1339 /* Drop unused references */
1340 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1341 dqput(got[cnt]);
1342 return ret;
1343}
1344EXPORT_SYMBOL(dquot_initialize);
1345
1346/*
1347 * Release all quotas referenced by inode
1348 */
1349int dquot_drop(struct inode *inode)
1350{
1351 int cnt;
1352 struct dquot *put[MAXQUOTAS];
1353
1354 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1355 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1356 put[cnt] = inode->i_dquot[cnt];
1357 inode->i_dquot[cnt] = NULL;
1358 }
1359 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1360
1361 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1362 dqput(put[cnt]);
1363 return 0;
1364}
1365EXPORT_SYMBOL(dquot_drop);
1366
1367/* Wrapper to remove references to quota structures from inode */
1368void vfs_dq_drop(struct inode *inode)
1369{
1370 /* Here we can get arbitrary inode from clear_inode() so we have
1371 * to be careful. OTOH we don't need locking as quota operations
1372 * are allowed to change only at mount time */
1373 if (!IS_NOQUOTA(inode) && inode->i_sb && inode->i_sb->dq_op
1374 && inode->i_sb->dq_op->drop) {
1375 int cnt;
1376 /* Test before calling to rule out calls from proc and such
1377 * where we are not allowed to block. Note that this is
1378 * actually reliable test even without the lock - the caller
1379 * must assure that nobody can come after the DQUOT_DROP and
1380 * add quota pointers back anyway */
1381 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1382 if (inode->i_dquot[cnt])
1383 break;
1384 if (cnt < MAXQUOTAS)
1385 inode->i_sb->dq_op->drop(inode);
1386 }
1387}
1388EXPORT_SYMBOL(vfs_dq_drop);
1389
1390/*
1391 * Following four functions update i_blocks+i_bytes fields and
1392 * quota information (together with appropriate checks)
1393 * NOTE: We absolutely rely on the fact that caller dirties
1394 * the inode (usually macros in quotaops.h care about this) and
1395 * holds a handle for the current transaction so that dquot write and
1396 * inode write go into the same transaction.
1397 */
1398
1399/*
1400 * This operation can block, but only after everything is updated
1401 */
1402int __dquot_alloc_space(struct inode *inode, qsize_t number,
1403 int warn, int reserve)
1404{
1405 int cnt, ret = QUOTA_OK;
1406 char warntype[MAXQUOTAS];
1407
1408 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1409 warntype[cnt] = QUOTA_NL_NOWARN;
1410
1411 spin_lock(&dq_data_lock);
1412 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1413 if (!inode->i_dquot[cnt])
1414 continue;
1415 if (check_bdq(inode->i_dquot[cnt], number, warn, warntype+cnt)
1416 == NO_QUOTA) {
1417 ret = NO_QUOTA;
1418 goto out_unlock;
1419 }
1420 }
1421 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1422 if (!inode->i_dquot[cnt])
1423 continue;
1424 if (reserve)
1425 dquot_resv_space(inode->i_dquot[cnt], number);
1426 else
1427 dquot_incr_space(inode->i_dquot[cnt], number);
1428 }
1429 if (!reserve)
1430 inode_add_bytes(inode, number);
1431out_unlock:
1432 spin_unlock(&dq_data_lock);
1433 flush_warnings(inode->i_dquot, warntype);
1434 return ret;
1435}
1436
1437int dquot_alloc_space(struct inode *inode, qsize_t number, int warn)
1438{
1439 int cnt, ret = QUOTA_OK;
1440
1441 /*
1442 * First test before acquiring mutex - solves deadlocks when we
1443 * re-enter the quota code and are already holding the mutex
1444 */
1445 if (IS_NOQUOTA(inode)) {
1446 inode_add_bytes(inode, number);
1447 goto out;
1448 }
1449
1450 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1451 if (IS_NOQUOTA(inode)) {
1452 inode_add_bytes(inode, number);
1453 goto out_unlock;
1454 }
1455
1456 ret = __dquot_alloc_space(inode, number, warn, 0);
1457 if (ret == NO_QUOTA)
1458 goto out_unlock;
1459
1460 /* Dirtify all the dquots - this can block when journalling */
1461 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1462 if (inode->i_dquot[cnt])
1463 mark_dquot_dirty(inode->i_dquot[cnt]);
1464out_unlock:
1465 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1466out:
1467 return ret;
1468}
1469EXPORT_SYMBOL(dquot_alloc_space);
1470
1471int dquot_reserve_space(struct inode *inode, qsize_t number, int warn)
1472{
1473 int ret = QUOTA_OK;
1474
1475 if (IS_NOQUOTA(inode))
1476 goto out;
1477
1478 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1479 if (IS_NOQUOTA(inode))
1480 goto out_unlock;
1481
1482 ret = __dquot_alloc_space(inode, number, warn, 1);
1483out_unlock:
1484 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1485out:
1486 return ret;
1487}
1488EXPORT_SYMBOL(dquot_reserve_space);
1489
1490/*
1491 * This operation can block, but only after everything is updated
1492 */
1493int dquot_alloc_inode(const struct inode *inode, qsize_t number)
1494{
1495 int cnt, ret = NO_QUOTA;
1496 char warntype[MAXQUOTAS];
1497
1498 /* First test before acquiring mutex - solves deadlocks when we
1499 * re-enter the quota code and are already holding the mutex */
1500 if (IS_NOQUOTA(inode))
1501 return QUOTA_OK;
1502 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1503 warntype[cnt] = QUOTA_NL_NOWARN;
1504 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1505 if (IS_NOQUOTA(inode)) {
1506 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1507 return QUOTA_OK;
1508 }
1509 spin_lock(&dq_data_lock);
1510 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1511 if (!inode->i_dquot[cnt])
1512 continue;
1513 if (check_idq(inode->i_dquot[cnt], number, warntype+cnt)
1514 == NO_QUOTA)
1515 goto warn_put_all;
1516 }
1517
1518 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1519 if (!inode->i_dquot[cnt])
1520 continue;
1521 dquot_incr_inodes(inode->i_dquot[cnt], number);
1522 }
1523 ret = QUOTA_OK;
1524warn_put_all:
1525 spin_unlock(&dq_data_lock);
1526 if (ret == QUOTA_OK)
1527 /* Dirtify all the dquots - this can block when journalling */
1528 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1529 if (inode->i_dquot[cnt])
1530 mark_dquot_dirty(inode->i_dquot[cnt]);
1531 flush_warnings(inode->i_dquot, warntype);
1532 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1533 return ret;
1534}
1535EXPORT_SYMBOL(dquot_alloc_inode);
1536
1537int dquot_claim_space(struct inode *inode, qsize_t number)
1538{
1539 int cnt;
1540 int ret = QUOTA_OK;
1541
1542 if (IS_NOQUOTA(inode)) {
1543 inode_add_bytes(inode, number);
1544 goto out;
1545 }
1546
1547 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1548 if (IS_NOQUOTA(inode)) {
1549 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1550 inode_add_bytes(inode, number);
1551 goto out;
1552 }
1553
1554 spin_lock(&dq_data_lock);
1555 /* Claim reserved quotas to allocated quotas */
1556 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1557 if (inode->i_dquot[cnt])
1558 dquot_claim_reserved_space(inode->i_dquot[cnt],
1559 number);
1560 }
1561 /* Update inode bytes */
1562 inode_add_bytes(inode, number);
1563 spin_unlock(&dq_data_lock);
1564 /* Dirtify all the dquots - this can block when journalling */
1565 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1566 if (inode->i_dquot[cnt])
1567 mark_dquot_dirty(inode->i_dquot[cnt]);
1568 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1569out:
1570 return ret;
1571}
1572EXPORT_SYMBOL(dquot_claim_space);
1573
1574/*
1575 * Release reserved quota space
1576 */
1577void dquot_release_reserved_space(struct inode *inode, qsize_t number)
1578{
1579 int cnt;
1580
1581 if (IS_NOQUOTA(inode))
1582 goto out;
1583
1584 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1585 if (IS_NOQUOTA(inode))
1586 goto out_unlock;
1587
1588 spin_lock(&dq_data_lock);
1589 /* Release reserved dquots */
1590 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1591 if (inode->i_dquot[cnt])
1592 dquot_free_reserved_space(inode->i_dquot[cnt], number);
1593 }
1594 spin_unlock(&dq_data_lock);
1595
1596out_unlock:
1597 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1598out:
1599 return;
1600}
1601EXPORT_SYMBOL(dquot_release_reserved_space);
1602
1603/*
1604 * This operation can block, but only after everything is updated
1605 */
1606int dquot_free_space(struct inode *inode, qsize_t number)
1607{
1608 unsigned int cnt;
1609 char warntype[MAXQUOTAS];
1610
1611 /* First test before acquiring mutex - solves deadlocks when we
1612 * re-enter the quota code and are already holding the mutex */
1613 if (IS_NOQUOTA(inode)) {
1614out_sub:
1615 inode_sub_bytes(inode, number);
1616 return QUOTA_OK;
1617 }
1618
1619 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1620 /* Now recheck reliably when holding dqptr_sem */
1621 if (IS_NOQUOTA(inode)) {
1622 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1623 goto out_sub;
1624 }
1625 spin_lock(&dq_data_lock);
1626 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1627 if (!inode->i_dquot[cnt])
1628 continue;
1629 warntype[cnt] = info_bdq_free(inode->i_dquot[cnt], number);
1630 dquot_decr_space(inode->i_dquot[cnt], number);
1631 }
1632 inode_sub_bytes(inode, number);
1633 spin_unlock(&dq_data_lock);
1634 /* Dirtify all the dquots - this can block when journalling */
1635 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1636 if (inode->i_dquot[cnt])
1637 mark_dquot_dirty(inode->i_dquot[cnt]);
1638 flush_warnings(inode->i_dquot, warntype);
1639 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1640 return QUOTA_OK;
1641}
1642EXPORT_SYMBOL(dquot_free_space);
1643
1644/*
1645 * This operation can block, but only after everything is updated
1646 */
1647int dquot_free_inode(const struct inode *inode, qsize_t number)
1648{
1649 unsigned int cnt;
1650 char warntype[MAXQUOTAS];
1651
1652 /* First test before acquiring mutex - solves deadlocks when we
1653 * re-enter the quota code and are already holding the mutex */
1654 if (IS_NOQUOTA(inode))
1655 return QUOTA_OK;
1656
1657 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1658 /* Now recheck reliably when holding dqptr_sem */
1659 if (IS_NOQUOTA(inode)) {
1660 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1661 return QUOTA_OK;
1662 }
1663 spin_lock(&dq_data_lock);
1664 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1665 if (!inode->i_dquot[cnt])
1666 continue;
1667 warntype[cnt] = info_idq_free(inode->i_dquot[cnt], number);
1668 dquot_decr_inodes(inode->i_dquot[cnt], number);
1669 }
1670 spin_unlock(&dq_data_lock);
1671 /* Dirtify all the dquots - this can block when journalling */
1672 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1673 if (inode->i_dquot[cnt])
1674 mark_dquot_dirty(inode->i_dquot[cnt]);
1675 flush_warnings(inode->i_dquot, warntype);
1676 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1677 return QUOTA_OK;
1678}
1679EXPORT_SYMBOL(dquot_free_inode);
1680
1681/*
1682 * call back function, get reserved quota space from underlying fs
1683 */
1684qsize_t dquot_get_reserved_space(struct inode *inode)
1685{
1686 qsize_t reserved_space = 0;
1687
1688 if (sb_any_quota_active(inode->i_sb) &&
1689 inode->i_sb->dq_op->get_reserved_space)
1690 reserved_space = inode->i_sb->dq_op->get_reserved_space(inode);
1691 return reserved_space;
1692}
1693
1694/*
1695 * Transfer the number of inode and blocks from one diskquota to an other.
1696 *
1697 * This operation can block, but only after everything is updated
1698 * A transaction must be started when entering this function.
1699 */
1700int dquot_transfer(struct inode *inode, struct iattr *iattr)
1701{
1702 qsize_t space, cur_space;
1703 qsize_t rsv_space = 0;
1704 struct dquot *transfer_from[MAXQUOTAS];
1705 struct dquot *transfer_to[MAXQUOTAS];
1706 int cnt, ret = QUOTA_OK;
1707 int chuid = iattr->ia_valid & ATTR_UID && inode->i_uid != iattr->ia_uid,
1708 chgid = iattr->ia_valid & ATTR_GID && inode->i_gid != iattr->ia_gid;
1709 char warntype_to[MAXQUOTAS];
1710 char warntype_from_inodes[MAXQUOTAS], warntype_from_space[MAXQUOTAS];
1711
1712 /* First test before acquiring mutex - solves deadlocks when we
1713 * re-enter the quota code and are already holding the mutex */
1714 if (IS_NOQUOTA(inode))
1715 return QUOTA_OK;
1716 /* Initialize the arrays */
1717 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1718 transfer_from[cnt] = NULL;
1719 transfer_to[cnt] = NULL;
1720 warntype_to[cnt] = QUOTA_NL_NOWARN;
1721 }
1722 if (chuid)
1723 transfer_to[USRQUOTA] = dqget(inode->i_sb, iattr->ia_uid,
1724 USRQUOTA);
1725 if (chgid)
1726 transfer_to[GRPQUOTA] = dqget(inode->i_sb, iattr->ia_gid,
1727 GRPQUOTA);
1728
1729 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1730 /* Now recheck reliably when holding dqptr_sem */
1731 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */
1732 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1733 goto put_all;
1734 }
1735 spin_lock(&dq_data_lock);
1736 cur_space = inode_get_bytes(inode);
1737 rsv_space = dquot_get_reserved_space(inode);
1738 space = cur_space + rsv_space;
1739 /* Build the transfer_from list and check the limits */
1740 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1741 if (!transfer_to[cnt])
1742 continue;
1743 transfer_from[cnt] = inode->i_dquot[cnt];
1744 if (check_idq(transfer_to[cnt], 1, warntype_to + cnt) ==
1745 NO_QUOTA || check_bdq(transfer_to[cnt], space, 0,
1746 warntype_to + cnt) == NO_QUOTA)
1747 goto over_quota;
1748 }
1749
1750 /*
1751 * Finally perform the needed transfer from transfer_from to transfer_to
1752 */
1753 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1754 /*
1755 * Skip changes for same uid or gid or for turned off quota-type.
1756 */
1757 if (!transfer_to[cnt])
1758 continue;
1759
1760 /* Due to IO error we might not have transfer_from[] structure */
1761 if (transfer_from[cnt]) {
1762 warntype_from_inodes[cnt] =
1763 info_idq_free(transfer_from[cnt], 1);
1764 warntype_from_space[cnt] =
1765 info_bdq_free(transfer_from[cnt], space);
1766 dquot_decr_inodes(transfer_from[cnt], 1);
1767 dquot_decr_space(transfer_from[cnt], cur_space);
1768 dquot_free_reserved_space(transfer_from[cnt],
1769 rsv_space);
1770 }
1771
1772 dquot_incr_inodes(transfer_to[cnt], 1);
1773 dquot_incr_space(transfer_to[cnt], cur_space);
1774 dquot_resv_space(transfer_to[cnt], rsv_space);
1775
1776 inode->i_dquot[cnt] = transfer_to[cnt];
1777 }
1778 spin_unlock(&dq_data_lock);
1779 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1780
1781 /* Dirtify all the dquots - this can block when journalling */
1782 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1783 if (transfer_from[cnt])
1784 mark_dquot_dirty(transfer_from[cnt]);
1785 if (transfer_to[cnt]) {
1786 mark_dquot_dirty(transfer_to[cnt]);
1787 /* The reference we got is transferred to the inode */
1788 transfer_to[cnt] = NULL;
1789 }
1790 }
1791warn_put_all:
1792 flush_warnings(transfer_to, warntype_to);
1793 flush_warnings(transfer_from, warntype_from_inodes);
1794 flush_warnings(transfer_from, warntype_from_space);
1795put_all:
1796 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1797 dqput(transfer_from[cnt]);
1798 dqput(transfer_to[cnt]);
1799 }
1800 return ret;
1801over_quota:
1802 spin_unlock(&dq_data_lock);
1803 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1804 /* Clear dquot pointers we don't want to dqput() */
1805 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1806 transfer_from[cnt] = NULL;
1807 ret = NO_QUOTA;
1808 goto warn_put_all;
1809}
1810EXPORT_SYMBOL(dquot_transfer);
1811
1812/* Wrapper for transferring ownership of an inode */
1813int vfs_dq_transfer(struct inode *inode, struct iattr *iattr)
1814{
1815 if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode)) {
1816 vfs_dq_init(inode);
1817 if (inode->i_sb->dq_op->transfer(inode, iattr) == NO_QUOTA)
1818 return 1;
1819 }
1820 return 0;
1821}
1822EXPORT_SYMBOL(vfs_dq_transfer);
1823
1824/*
1825 * Write info of quota file to disk
1826 */
1827int dquot_commit_info(struct super_block *sb, int type)
1828{
1829 int ret;
1830 struct quota_info *dqopt = sb_dqopt(sb);
1831
1832 mutex_lock(&dqopt->dqio_mutex);
1833 ret = dqopt->ops[type]->write_file_info(sb, type);
1834 mutex_unlock(&dqopt->dqio_mutex);
1835 return ret;
1836}
1837EXPORT_SYMBOL(dquot_commit_info);
1838
1839/*
1840 * Definitions of diskquota operations.
1841 */
1842struct dquot_operations dquot_operations = {
1843 .initialize = dquot_initialize,
1844 .drop = dquot_drop,
1845 .alloc_space = dquot_alloc_space,
1846 .alloc_inode = dquot_alloc_inode,
1847 .free_space = dquot_free_space,
1848 .free_inode = dquot_free_inode,
1849 .transfer = dquot_transfer,
1850 .write_dquot = dquot_commit,
1851 .acquire_dquot = dquot_acquire,
1852 .release_dquot = dquot_release,
1853 .mark_dirty = dquot_mark_dquot_dirty,
1854 .write_info = dquot_commit_info,
1855 .alloc_dquot = dquot_alloc,
1856 .destroy_dquot = dquot_destroy,
1857};
1858
1859/*
1860 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount)
1861 */
1862int vfs_quota_disable(struct super_block *sb, int type, unsigned int flags)
1863{
1864 int cnt, ret = 0;
1865 struct quota_info *dqopt = sb_dqopt(sb);
1866 struct inode *toputinode[MAXQUOTAS];
1867
1868 /* Cannot turn off usage accounting without turning off limits, or
1869 * suspend quotas and simultaneously turn quotas off. */
1870 if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED))
1871 || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED |
1872 DQUOT_USAGE_ENABLED)))
1873 return -EINVAL;
1874
1875 /* We need to serialize quota_off() for device */
1876 mutex_lock(&dqopt->dqonoff_mutex);
1877
1878 /*
1879 * Skip everything if there's nothing to do. We have to do this because
1880 * sometimes we are called when fill_super() failed and calling
1881 * sync_fs() in such cases does no good.
1882 */
1883 if (!sb_any_quota_loaded(sb)) {
1884 mutex_unlock(&dqopt->dqonoff_mutex);
1885 return 0;
1886 }
1887 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1888 toputinode[cnt] = NULL;
1889 if (type != -1 && cnt != type)
1890 continue;
1891 if (!sb_has_quota_loaded(sb, cnt))
1892 continue;
1893
1894 if (flags & DQUOT_SUSPENDED) {
1895 spin_lock(&dq_state_lock);
1896 dqopt->flags |=
1897 dquot_state_flag(DQUOT_SUSPENDED, cnt);
1898 spin_unlock(&dq_state_lock);
1899 } else {
1900 spin_lock(&dq_state_lock);
1901 dqopt->flags &= ~dquot_state_flag(flags, cnt);
1902 /* Turning off suspended quotas? */
1903 if (!sb_has_quota_loaded(sb, cnt) &&
1904 sb_has_quota_suspended(sb, cnt)) {
1905 dqopt->flags &= ~dquot_state_flag(
1906 DQUOT_SUSPENDED, cnt);
1907 spin_unlock(&dq_state_lock);
1908 iput(dqopt->files[cnt]);
1909 dqopt->files[cnt] = NULL;
1910 continue;
1911 }
1912 spin_unlock(&dq_state_lock);
1913 }
1914
1915 /* We still have to keep quota loaded? */
1916 if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED))
1917 continue;
1918
1919 /* Note: these are blocking operations */
1920 drop_dquot_ref(sb, cnt);
1921 invalidate_dquots(sb, cnt);
1922 /*
1923 * Now all dquots should be invalidated, all writes done so we
1924 * should be only users of the info. No locks needed.
1925 */
1926 if (info_dirty(&dqopt->info[cnt]))
1927 sb->dq_op->write_info(sb, cnt);
1928 if (dqopt->ops[cnt]->free_file_info)
1929 dqopt->ops[cnt]->free_file_info(sb, cnt);
1930 put_quota_format(dqopt->info[cnt].dqi_format);
1931
1932 toputinode[cnt] = dqopt->files[cnt];
1933 if (!sb_has_quota_loaded(sb, cnt))
1934 dqopt->files[cnt] = NULL;
1935 dqopt->info[cnt].dqi_flags = 0;
1936 dqopt->info[cnt].dqi_igrace = 0;
1937 dqopt->info[cnt].dqi_bgrace = 0;
1938 dqopt->ops[cnt] = NULL;
1939 }
1940 mutex_unlock(&dqopt->dqonoff_mutex);
1941
1942 /* Skip syncing and setting flags if quota files are hidden */
1943 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE)
1944 goto put_inodes;
1945
1946 /* Sync the superblock so that buffers with quota data are written to
1947 * disk (and so userspace sees correct data afterwards). */
1948 if (sb->s_op->sync_fs)
1949 sb->s_op->sync_fs(sb, 1);
1950 sync_blockdev(sb->s_bdev);
1951 /* Now the quota files are just ordinary files and we can set the
1952 * inode flags back. Moreover we discard the pagecache so that
1953 * userspace sees the writes we did bypassing the pagecache. We
1954 * must also discard the blockdev buffers so that we see the
1955 * changes done by userspace on the next quotaon() */
1956 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1957 if (toputinode[cnt]) {
1958 mutex_lock(&dqopt->dqonoff_mutex);
1959 /* If quota was reenabled in the meantime, we have
1960 * nothing to do */
1961 if (!sb_has_quota_loaded(sb, cnt)) {
1962 mutex_lock_nested(&toputinode[cnt]->i_mutex,
1963 I_MUTEX_QUOTA);
1964 toputinode[cnt]->i_flags &= ~(S_IMMUTABLE |
1965 S_NOATIME | S_NOQUOTA);
1966 truncate_inode_pages(&toputinode[cnt]->i_data,
1967 0);
1968 mutex_unlock(&toputinode[cnt]->i_mutex);
1969 mark_inode_dirty(toputinode[cnt]);
1970 }
1971 mutex_unlock(&dqopt->dqonoff_mutex);
1972 }
1973 if (sb->s_bdev)
1974 invalidate_bdev(sb->s_bdev);
1975put_inodes:
1976 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1977 if (toputinode[cnt]) {
1978 /* On remount RO, we keep the inode pointer so that we
1979 * can reenable quota on the subsequent remount RW. We
1980 * have to check 'flags' variable and not use sb_has_
1981 * function because another quotaon / quotaoff could
1982 * change global state before we got here. We refuse
1983 * to suspend quotas when there is pending delete on
1984 * the quota file... */
1985 if (!(flags & DQUOT_SUSPENDED))
1986 iput(toputinode[cnt]);
1987 else if (!toputinode[cnt]->i_nlink)
1988 ret = -EBUSY;
1989 }
1990 return ret;
1991}
1992EXPORT_SYMBOL(vfs_quota_disable);
1993
1994int vfs_quota_off(struct super_block *sb, int type, int remount)
1995{
1996 return vfs_quota_disable(sb, type, remount ? DQUOT_SUSPENDED :
1997 (DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED));
1998}
1999EXPORT_SYMBOL(vfs_quota_off);
2000/*
2001 * Turn quotas on on a device
2002 */
2003
2004/*
2005 * Helper function to turn quotas on when we already have the inode of
2006 * quota file and no quota information is loaded.
2007 */
2008static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
2009 unsigned int flags)
2010{
2011 struct quota_format_type *fmt = find_quota_format(format_id);
2012 struct super_block *sb = inode->i_sb;
2013 struct quota_info *dqopt = sb_dqopt(sb);
2014 int error;
2015 int oldflags = -1;
2016
2017 if (!fmt)
2018 return -ESRCH;
2019 if (!S_ISREG(inode->i_mode)) {
2020 error = -EACCES;
2021 goto out_fmt;
2022 }
2023 if (IS_RDONLY(inode)) {
2024 error = -EROFS;
2025 goto out_fmt;
2026 }
2027 if (!sb->s_op->quota_write || !sb->s_op->quota_read) {
2028 error = -EINVAL;
2029 goto out_fmt;
2030 }
2031 /* Usage always has to be set... */
2032 if (!(flags & DQUOT_USAGE_ENABLED)) {
2033 error = -EINVAL;
2034 goto out_fmt;
2035 }
2036
2037 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) {
2038 /* As we bypass the pagecache we must now flush the inode so
2039 * that we see all the changes from userspace... */
2040 write_inode_now(inode, 1);
2041 /* And now flush the block cache so that kernel sees the
2042 * changes */
2043 invalidate_bdev(sb->s_bdev);
2044 }
2045 mutex_lock(&inode->i_mutex);
2046 mutex_lock(&dqopt->dqonoff_mutex);
2047 if (sb_has_quota_loaded(sb, type)) {
2048 error = -EBUSY;
2049 goto out_lock;
2050 }
2051
2052 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) {
2053 /* We don't want quota and atime on quota files (deadlocks
2054 * possible) Also nobody should write to the file - we use
2055 * special IO operations which ignore the immutable bit. */
2056 down_write(&dqopt->dqptr_sem);
2057 oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE |
2058 S_NOQUOTA);
2059 inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE;
2060 up_write(&dqopt->dqptr_sem);
2061 sb->dq_op->drop(inode);
2062 }
2063
2064 error = -EIO;
2065 dqopt->files[type] = igrab(inode);
2066 if (!dqopt->files[type])
2067 goto out_lock;
2068 error = -EINVAL;
2069 if (!fmt->qf_ops->check_quota_file(sb, type))
2070 goto out_file_init;
2071
2072 dqopt->ops[type] = fmt->qf_ops;
2073 dqopt->info[type].dqi_format = fmt;
2074 dqopt->info[type].dqi_fmt_id = format_id;
2075 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list);
2076 mutex_lock(&dqopt->dqio_mutex);
2077 error = dqopt->ops[type]->read_file_info(sb, type);
2078 if (error < 0) {
2079 mutex_unlock(&dqopt->dqio_mutex);
2080 goto out_file_init;
2081 }
2082 mutex_unlock(&dqopt->dqio_mutex);
2083 mutex_unlock(&inode->i_mutex);
2084 spin_lock(&dq_state_lock);
2085 dqopt->flags |= dquot_state_flag(flags, type);
2086 spin_unlock(&dq_state_lock);
2087
2088 add_dquot_ref(sb, type);
2089 mutex_unlock(&dqopt->dqonoff_mutex);
2090
2091 return 0;
2092
2093out_file_init:
2094 dqopt->files[type] = NULL;
2095 iput(inode);
2096out_lock:
2097 mutex_unlock(&dqopt->dqonoff_mutex);
2098 if (oldflags != -1) {
2099 down_write(&dqopt->dqptr_sem);
2100 /* Set the flags back (in the case of accidental quotaon()
2101 * on a wrong file we don't want to mess up the flags) */
2102 inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE);
2103 inode->i_flags |= oldflags;
2104 up_write(&dqopt->dqptr_sem);
2105 }
2106 mutex_unlock(&inode->i_mutex);
2107out_fmt:
2108 put_quota_format(fmt);
2109
2110 return error;
2111}
2112
2113/* Reenable quotas on remount RW */
2114static int vfs_quota_on_remount(struct super_block *sb, int type)
2115{
2116 struct quota_info *dqopt = sb_dqopt(sb);
2117 struct inode *inode;
2118 int ret;
2119 unsigned int flags;
2120
2121 mutex_lock(&dqopt->dqonoff_mutex);
2122 if (!sb_has_quota_suspended(sb, type)) {
2123 mutex_unlock(&dqopt->dqonoff_mutex);
2124 return 0;
2125 }
2126 inode = dqopt->files[type];
2127 dqopt->files[type] = NULL;
2128 spin_lock(&dq_state_lock);
2129 flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED |
2130 DQUOT_LIMITS_ENABLED, type);
2131 dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, type);
2132 spin_unlock(&dq_state_lock);
2133 mutex_unlock(&dqopt->dqonoff_mutex);
2134
2135 flags = dquot_generic_flag(flags, type);
2136 ret = vfs_load_quota_inode(inode, type, dqopt->info[type].dqi_fmt_id,
2137 flags);
2138 iput(inode);
2139
2140 return ret;
2141}
2142
2143int vfs_quota_on_path(struct super_block *sb, int type, int format_id,
2144 struct path *path)
2145{
2146 int error = security_quota_on(path->dentry);
2147 if (error)
2148 return error;
2149 /* Quota file not on the same filesystem? */
2150 if (path->mnt->mnt_sb != sb)
2151 error = -EXDEV;
2152 else
2153 error = vfs_load_quota_inode(path->dentry->d_inode, type,
2154 format_id, DQUOT_USAGE_ENABLED |
2155 DQUOT_LIMITS_ENABLED);
2156 return error;
2157}
2158EXPORT_SYMBOL(vfs_quota_on_path);
2159
2160int vfs_quota_on(struct super_block *sb, int type, int format_id, char *name,
2161 int remount)
2162{
2163 struct path path;
2164 int error;
2165
2166 if (remount)
2167 return vfs_quota_on_remount(sb, type);
2168
2169 error = kern_path(name, LOOKUP_FOLLOW, &path);
2170 if (!error) {
2171 error = vfs_quota_on_path(sb, type, format_id, &path);
2172 path_put(&path);
2173 }
2174 return error;
2175}
2176EXPORT_SYMBOL(vfs_quota_on);
2177
2178/*
2179 * More powerful function for turning on quotas allowing setting
2180 * of individual quota flags
2181 */
2182int vfs_quota_enable(struct inode *inode, int type, int format_id,
2183 unsigned int flags)
2184{
2185 int ret = 0;
2186 struct super_block *sb = inode->i_sb;
2187 struct quota_info *dqopt = sb_dqopt(sb);
2188
2189 /* Just unsuspend quotas? */
2190 if (flags & DQUOT_SUSPENDED)
2191 return vfs_quota_on_remount(sb, type);
2192 if (!flags)
2193 return 0;
2194 /* Just updating flags needed? */
2195 if (sb_has_quota_loaded(sb, type)) {
2196 mutex_lock(&dqopt->dqonoff_mutex);
2197 /* Now do a reliable test... */
2198 if (!sb_has_quota_loaded(sb, type)) {
2199 mutex_unlock(&dqopt->dqonoff_mutex);
2200 goto load_quota;
2201 }
2202 if (flags & DQUOT_USAGE_ENABLED &&
2203 sb_has_quota_usage_enabled(sb, type)) {
2204 ret = -EBUSY;
2205 goto out_lock;
2206 }
2207 if (flags & DQUOT_LIMITS_ENABLED &&
2208 sb_has_quota_limits_enabled(sb, type)) {
2209 ret = -EBUSY;
2210 goto out_lock;
2211 }
2212 spin_lock(&dq_state_lock);
2213 sb_dqopt(sb)->flags |= dquot_state_flag(flags, type);
2214 spin_unlock(&dq_state_lock);
2215out_lock:
2216 mutex_unlock(&dqopt->dqonoff_mutex);
2217 return ret;
2218 }
2219
2220load_quota:
2221 return vfs_load_quota_inode(inode, type, format_id, flags);
2222}
2223EXPORT_SYMBOL(vfs_quota_enable);
2224
2225/*
2226 * This function is used when filesystem needs to initialize quotas
2227 * during mount time.
2228 */
2229int vfs_quota_on_mount(struct super_block *sb, char *qf_name,
2230 int format_id, int type)
2231{
2232 struct dentry *dentry;
2233 int error;
2234
2235 dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name));
2236 if (IS_ERR(dentry))
2237 return PTR_ERR(dentry);
2238
2239 if (!dentry->d_inode) {
2240 error = -ENOENT;
2241 goto out;
2242 }
2243
2244 error = security_quota_on(dentry);
2245 if (!error)
2246 error = vfs_load_quota_inode(dentry->d_inode, type, format_id,
2247 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
2248
2249out:
2250 dput(dentry);
2251 return error;
2252}
2253EXPORT_SYMBOL(vfs_quota_on_mount);
2254
2255/* Wrapper to turn on quotas when remounting rw */
2256int vfs_dq_quota_on_remount(struct super_block *sb)
2257{
2258 int cnt;
2259 int ret = 0, err;
2260
2261 if (!sb->s_qcop || !sb->s_qcop->quota_on)
2262 return -ENOSYS;
2263 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
2264 err = sb->s_qcop->quota_on(sb, cnt, 0, NULL, 1);
2265 if (err < 0 && !ret)
2266 ret = err;
2267 }
2268 return ret;
2269}
2270EXPORT_SYMBOL(vfs_dq_quota_on_remount);
2271
2272static inline qsize_t qbtos(qsize_t blocks)
2273{
2274 return blocks << QIF_DQBLKSIZE_BITS;
2275}
2276
2277static inline qsize_t stoqb(qsize_t space)
2278{
2279 return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS;
2280}
2281
2282/* Generic routine for getting common part of quota structure */
2283static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di)
2284{
2285 struct mem_dqblk *dm = &dquot->dq_dqb;
2286
2287 spin_lock(&dq_data_lock);
2288 di->dqb_bhardlimit = stoqb(dm->dqb_bhardlimit);
2289 di->dqb_bsoftlimit = stoqb(dm->dqb_bsoftlimit);
2290 di->dqb_curspace = dm->dqb_curspace + dm->dqb_rsvspace;
2291 di->dqb_ihardlimit = dm->dqb_ihardlimit;
2292 di->dqb_isoftlimit = dm->dqb_isoftlimit;
2293 di->dqb_curinodes = dm->dqb_curinodes;
2294 di->dqb_btime = dm->dqb_btime;
2295 di->dqb_itime = dm->dqb_itime;
2296 di->dqb_valid = QIF_ALL;
2297 spin_unlock(&dq_data_lock);
2298}
2299
2300int vfs_get_dqblk(struct super_block *sb, int type, qid_t id,
2301 struct if_dqblk *di)
2302{
2303 struct dquot *dquot;
2304
2305 dquot = dqget(sb, id, type);
2306 if (!dquot)
2307 return -ESRCH;
2308 do_get_dqblk(dquot, di);
2309 dqput(dquot);
2310
2311 return 0;
2312}
2313EXPORT_SYMBOL(vfs_get_dqblk);
2314
2315/* Generic routine for setting common part of quota structure */
2316static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
2317{
2318 struct mem_dqblk *dm = &dquot->dq_dqb;
2319 int check_blim = 0, check_ilim = 0;
2320 struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type];
2321
2322 if ((di->dqb_valid & QIF_BLIMITS &&
2323 (di->dqb_bhardlimit > dqi->dqi_maxblimit ||
2324 di->dqb_bsoftlimit > dqi->dqi_maxblimit)) ||
2325 (di->dqb_valid & QIF_ILIMITS &&
2326 (di->dqb_ihardlimit > dqi->dqi_maxilimit ||
2327 di->dqb_isoftlimit > dqi->dqi_maxilimit)))
2328 return -ERANGE;
2329
2330 spin_lock(&dq_data_lock);
2331 if (di->dqb_valid & QIF_SPACE) {
2332 dm->dqb_curspace = di->dqb_curspace - dm->dqb_rsvspace;
2333 check_blim = 1;
2334 __set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags);
2335 }
2336 if (di->dqb_valid & QIF_BLIMITS) {
2337 dm->dqb_bsoftlimit = qbtos(di->dqb_bsoftlimit);
2338 dm->dqb_bhardlimit = qbtos(di->dqb_bhardlimit);
2339 check_blim = 1;
2340 __set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags);
2341 }
2342 if (di->dqb_valid & QIF_INODES) {
2343 dm->dqb_curinodes = di->dqb_curinodes;
2344 check_ilim = 1;
2345 __set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags);
2346 }
2347 if (di->dqb_valid & QIF_ILIMITS) {
2348 dm->dqb_isoftlimit = di->dqb_isoftlimit;
2349 dm->dqb_ihardlimit = di->dqb_ihardlimit;
2350 check_ilim = 1;
2351 __set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags);
2352 }
2353 if (di->dqb_valid & QIF_BTIME) {
2354 dm->dqb_btime = di->dqb_btime;
2355 check_blim = 1;
2356 __set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags);
2357 }
2358 if (di->dqb_valid & QIF_ITIME) {
2359 dm->dqb_itime = di->dqb_itime;
2360 check_ilim = 1;
2361 __set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags);
2362 }
2363
2364 if (check_blim) {
2365 if (!dm->dqb_bsoftlimit ||
2366 dm->dqb_curspace < dm->dqb_bsoftlimit) {
2367 dm->dqb_btime = 0;
2368 clear_bit(DQ_BLKS_B, &dquot->dq_flags);
2369 } else if (!(di->dqb_valid & QIF_BTIME))
2370 /* Set grace only if user hasn't provided his own... */
2371 dm->dqb_btime = get_seconds() + dqi->dqi_bgrace;
2372 }
2373 if (check_ilim) {
2374 if (!dm->dqb_isoftlimit ||
2375 dm->dqb_curinodes < dm->dqb_isoftlimit) {
2376 dm->dqb_itime = 0;
2377 clear_bit(DQ_INODES_B, &dquot->dq_flags);
2378 } else if (!(di->dqb_valid & QIF_ITIME))
2379 /* Set grace only if user hasn't provided his own... */
2380 dm->dqb_itime = get_seconds() + dqi->dqi_igrace;
2381 }
2382 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit ||
2383 dm->dqb_isoftlimit)
2384 clear_bit(DQ_FAKE_B, &dquot->dq_flags);
2385 else
2386 set_bit(DQ_FAKE_B, &dquot->dq_flags);
2387 spin_unlock(&dq_data_lock);
2388 mark_dquot_dirty(dquot);
2389
2390 return 0;
2391}
2392
2393int vfs_set_dqblk(struct super_block *sb, int type, qid_t id,
2394 struct if_dqblk *di)
2395{
2396 struct dquot *dquot;
2397 int rc;
2398
2399 dquot = dqget(sb, id, type);
2400 if (!dquot) {
2401 rc = -ESRCH;
2402 goto out;
2403 }
2404 rc = do_set_dqblk(dquot, di);
2405 dqput(dquot);
2406out:
2407 return rc;
2408}
2409EXPORT_SYMBOL(vfs_set_dqblk);
2410
2411/* Generic routine for getting common part of quota file information */
2412int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii)
2413{
2414 struct mem_dqinfo *mi;
2415
2416 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
2417 if (!sb_has_quota_active(sb, type)) {
2418 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
2419 return -ESRCH;
2420 }
2421 mi = sb_dqopt(sb)->info + type;
2422 spin_lock(&dq_data_lock);
2423 ii->dqi_bgrace = mi->dqi_bgrace;
2424 ii->dqi_igrace = mi->dqi_igrace;
2425 ii->dqi_flags = mi->dqi_flags & DQF_MASK;
2426 ii->dqi_valid = IIF_ALL;
2427 spin_unlock(&dq_data_lock);
2428 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
2429 return 0;
2430}
2431EXPORT_SYMBOL(vfs_get_dqinfo);
2432
2433/* Generic routine for setting common part of quota file information */
2434int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii)
2435{
2436 struct mem_dqinfo *mi;
2437 int err = 0;
2438
2439 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
2440 if (!sb_has_quota_active(sb, type)) {
2441 err = -ESRCH;
2442 goto out;
2443 }
2444 mi = sb_dqopt(sb)->info + type;
2445 spin_lock(&dq_data_lock);
2446 if (ii->dqi_valid & IIF_BGRACE)
2447 mi->dqi_bgrace = ii->dqi_bgrace;
2448 if (ii->dqi_valid & IIF_IGRACE)
2449 mi->dqi_igrace = ii->dqi_igrace;
2450 if (ii->dqi_valid & IIF_FLAGS)
2451 mi->dqi_flags = (mi->dqi_flags & ~DQF_MASK) |
2452 (ii->dqi_flags & DQF_MASK);
2453 spin_unlock(&dq_data_lock);
2454 mark_info_dirty(sb, type);
2455 /* Force write to disk */
2456 sb->dq_op->write_info(sb, type);
2457out:
2458 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
2459 return err;
2460}
2461EXPORT_SYMBOL(vfs_set_dqinfo);
2462
2463struct quotactl_ops vfs_quotactl_ops = {
2464 .quota_on = vfs_quota_on,
2465 .quota_off = vfs_quota_off,
2466 .quota_sync = vfs_quota_sync,
2467 .get_info = vfs_get_dqinfo,
2468 .set_info = vfs_set_dqinfo,
2469 .get_dqblk = vfs_get_dqblk,
2470 .set_dqblk = vfs_set_dqblk
2471};
2472
2473static ctl_table fs_dqstats_table[] = {
2474 {
2475 .ctl_name = FS_DQ_LOOKUPS,
2476 .procname = "lookups",
2477 .data = &dqstats.lookups,
2478 .maxlen = sizeof(int),
2479 .mode = 0444,
2480 .proc_handler = &proc_dointvec,
2481 },
2482 {
2483 .ctl_name = FS_DQ_DROPS,
2484 .procname = "drops",
2485 .data = &dqstats.drops,
2486 .maxlen = sizeof(int),
2487 .mode = 0444,
2488 .proc_handler = &proc_dointvec,
2489 },
2490 {
2491 .ctl_name = FS_DQ_READS,
2492 .procname = "reads",
2493 .data = &dqstats.reads,
2494 .maxlen = sizeof(int),
2495 .mode = 0444,
2496 .proc_handler = &proc_dointvec,
2497 },
2498 {
2499 .ctl_name = FS_DQ_WRITES,
2500 .procname = "writes",
2501 .data = &dqstats.writes,
2502 .maxlen = sizeof(int),
2503 .mode = 0444,
2504 .proc_handler = &proc_dointvec,
2505 },
2506 {
2507 .ctl_name = FS_DQ_CACHE_HITS,
2508 .procname = "cache_hits",
2509 .data = &dqstats.cache_hits,
2510 .maxlen = sizeof(int),
2511 .mode = 0444,
2512 .proc_handler = &proc_dointvec,
2513 },
2514 {
2515 .ctl_name = FS_DQ_ALLOCATED,
2516 .procname = "allocated_dquots",
2517 .data = &dqstats.allocated_dquots,
2518 .maxlen = sizeof(int),
2519 .mode = 0444,
2520 .proc_handler = &proc_dointvec,
2521 },
2522 {
2523 .ctl_name = FS_DQ_FREE,
2524 .procname = "free_dquots",
2525 .data = &dqstats.free_dquots,
2526 .maxlen = sizeof(int),
2527 .mode = 0444,
2528 .proc_handler = &proc_dointvec,
2529 },
2530 {
2531 .ctl_name = FS_DQ_SYNCS,
2532 .procname = "syncs",
2533 .data = &dqstats.syncs,
2534 .maxlen = sizeof(int),
2535 .mode = 0444,
2536 .proc_handler = &proc_dointvec,
2537 },
2538#ifdef CONFIG_PRINT_QUOTA_WARNING
2539 {
2540 .ctl_name = FS_DQ_WARNINGS,
2541 .procname = "warnings",
2542 .data = &flag_print_warnings,
2543 .maxlen = sizeof(int),
2544 .mode = 0644,
2545 .proc_handler = &proc_dointvec,
2546 },
2547#endif
2548 { .ctl_name = 0 },
2549};
2550
2551static ctl_table fs_table[] = {
2552 {
2553 .ctl_name = FS_DQSTATS,
2554 .procname = "quota",
2555 .mode = 0555,
2556 .child = fs_dqstats_table,
2557 },
2558 { .ctl_name = 0 },
2559};
2560
2561static ctl_table sys_table[] = {
2562 {
2563 .ctl_name = CTL_FS,
2564 .procname = "fs",
2565 .mode = 0555,
2566 .child = fs_table,
2567 },
2568 { .ctl_name = 0 },
2569};
2570
2571static int __init dquot_init(void)
2572{
2573 int i;
2574 unsigned long nr_hash, order;
2575
2576 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__);
2577
2578 register_sysctl_table(sys_table);
2579
2580 dquot_cachep = kmem_cache_create("dquot",
2581 sizeof(struct dquot), sizeof(unsigned long) * 4,
2582 (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
2583 SLAB_MEM_SPREAD|SLAB_PANIC),
2584 NULL);
2585
2586 order = 0;
2587 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order);
2588 if (!dquot_hash)
2589 panic("Cannot create dquot hash table");
2590
2591 /* Find power-of-two hlist_heads which can fit into allocation */
2592 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head);
2593 dq_hash_bits = 0;
2594 do {
2595 dq_hash_bits++;
2596 } while (nr_hash >> dq_hash_bits);
2597 dq_hash_bits--;
2598
2599 nr_hash = 1UL << dq_hash_bits;
2600 dq_hash_mask = nr_hash - 1;
2601 for (i = 0; i < nr_hash; i++)
2602 INIT_HLIST_HEAD(dquot_hash + i);
2603
2604 printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n",
2605 nr_hash, order, (PAGE_SIZE << order));
2606
2607 register_shrinker(&dqcache_shrinker);
2608
2609#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
2610 if (genl_register_family(&quota_genl_family) != 0)
2611 printk(KERN_ERR
2612 "VFS: Failed to create quota netlink interface.\n");
2613#endif
2614
2615 return 0;
2616}
2617module_init(dquot_init);
generated by cgit v1.2.2 (git 2.25.0) at 2025-01-04 01:39:28 -0500