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.
12 * Version: $Id: dquot.c,v 6.3 1996/11/17 18:35:34 mvw Exp mvw $
14 * Author: Marco van Wieringen <mvw@planets.elm.net>
16 * Fixes: Dmitry Gorodchanin <pgmdsg@ibi.com>, 11 Feb 96
18 * Revised list management to avoid races
19 * -- Bill Hawes, <whawes@star.net>, 9/98
21 * Fixed races in dquot_transfer(), dqget() and dquot_alloc_...().
22 * As the consequence the locking was moved from dquot_decr_...(),
23 * dquot_incr_...() to calling functions.
24 * invalidate_dquots() now writes modified dquots.
25 * Serialized quota_off() and quota_on() for mount point.
26 * Fixed a few bugs in grow_dquots().
27 * Fixed deadlock in write_dquot() - we no longer account quotas on
29 * remove_dquot_ref() moved to inode.c - it now traverses through inodes
30 * add_dquot_ref() restarts after blocking
31 * Added check for bogus uid and fixed check for group in quotactl.
32 * Jan Kara, <jack@suse.cz>, sponsored by SuSE CR, 10-11/99
34 * Used struct list_head instead of own list struct
35 * Invalidation of referenced dquots is no longer possible
36 * Improved free_dquots list management
37 * Quota and i_blocks are now updated in one place to avoid races
38 * Warnings are now delayed so we won't block in critical section
39 * Write updated not to require dquot lock
40 * Jan Kara, <jack@suse.cz>, 9/2000
42 * Added dynamic quota structure allocation
43 * Jan Kara <jack@suse.cz> 12/2000
45 * Rewritten quota interface. Implemented new quota format and
46 * formats registering.
47 * Jan Kara, <jack@suse.cz>, 2001,2002
50 * Jan Kara, <jack@suse.cz>, 10/2002
52 * Added journalled quota support, fix lock inversion problems
53 * Jan Kara, <jack@suse.cz>, 2003,2004
55 * (C) Copyright 1994 - 1997 Marco van Wieringen
58 #include <linux/errno.h>
59 #include <linux/kernel.h>
61 #include <linux/mount.h>
63 #include <linux/time.h>
64 #include <linux/types.h>
65 #include <linux/string.h>
66 #include <linux/fcntl.h>
67 #include <linux/stat.h>
68 #include <linux/tty.h>
69 #include <linux/file.h>
70 #include <linux/slab.h>
71 #include <linux/sysctl.h>
72 #include <linux/smp_lock.h>
73 #include <linux/init.h>
74 #include <linux/module.h>
75 #include <linux/proc_fs.h>
76 #include <linux/security.h>
77 #include <linux/kmod.h>
78 #include <linux/namei.h>
79 #include <linux/buffer_head.h>
80 #include <linux/capability.h>
81 #include <linux/quotaops.h>
83 #include <asm/uaccess.h>
85 #define __DQUOT_PARANOIA
88 * There are two quota SMP locks. dq_list_lock protects all lists with quotas
89 * and quota formats and also dqstats structure containing statistics about the
90 * lists. dq_data_lock protects data from dq_dqb and also mem_dqinfo structures
91 * and also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes.
92 * i_blocks and i_bytes updates itself are guarded by i_lock acquired directly
93 * in inode_add_bytes() and inode_sub_bytes().
95 * The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock
97 * Note that some things (eg. sb pointer, type, id) doesn't change during
98 * the life of the dquot structure and so needn't to be protected by a lock
100 * Any operation working on dquots via inode pointers must hold dqptr_sem. If
101 * operation is just reading pointers from inode (or not using them at all) the
102 * read lock is enough. If pointers are altered function must hold write lock
103 * (these locking rules also apply for S_NOQUOTA flag in the inode - note that
104 * for altering the flag i_mutex is also needed). If operation is holding
105 * reference to dquot in other way (e.g. quotactl ops) it must be guarded by
107 * This locking assures that:
108 * a) update/access to dquot pointers in inode is serialized
109 * b) everyone is guarded against invalidate_dquots()
111 * Each dquot has its dq_lock semaphore. 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.
120 * Lock ordering (including related VFS locks) is the following:
121 * i_mutex > dqonoff_sem > journal_lock > dqptr_sem > dquot->dq_lock > dqio_sem
122 * i_mutex on quota files is special (it's below dqio_sem)
125 static DEFINE_SPINLOCK(dq_list_lock);
126 DEFINE_SPINLOCK(dq_data_lock);
128 static char *quotatypes[] = INITQFNAMES;
129 static struct quota_format_type *quota_formats; /* List of registered formats */
130 static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES;
132 /* SLAB cache for dquot structures */
133 static kmem_cache_t *dquot_cachep;
135 int register_quota_format(struct quota_format_type *fmt)
137 spin_lock(&dq_list_lock);
138 fmt->qf_next = quota_formats;
140 spin_unlock(&dq_list_lock);
144 void unregister_quota_format(struct quota_format_type *fmt)
146 struct quota_format_type **actqf;
148 spin_lock(&dq_list_lock);
149 for (actqf = "a_formats; *actqf && *actqf != fmt; actqf = &(*actqf)->qf_next);
151 *actqf = (*actqf)->qf_next;
152 spin_unlock(&dq_list_lock);
155 static struct quota_format_type *find_quota_format(int id)
157 struct quota_format_type *actqf;
159 spin_lock(&dq_list_lock);
160 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; actqf = actqf->qf_next);
161 if (!actqf || !try_module_get(actqf->qf_owner)) {
164 spin_unlock(&dq_list_lock);
166 for (qm = 0; module_names[qm].qm_fmt_id && module_names[qm].qm_fmt_id != id; qm++);
167 if (!module_names[qm].qm_fmt_id || request_module(module_names[qm].qm_mod_name))
170 spin_lock(&dq_list_lock);
171 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; actqf = actqf->qf_next);
172 if (actqf && !try_module_get(actqf->qf_owner))
175 spin_unlock(&dq_list_lock);
179 static void put_quota_format(struct quota_format_type *fmt)
181 module_put(fmt->qf_owner);
185 * Dquot List Management:
186 * The quota code uses three lists for dquot management: the inuse_list,
187 * free_dquots, and dquot_hash[] array. A single dquot structure may be
188 * on all three lists, depending on its current state.
190 * All dquots are placed to the end of inuse_list when first created, and this
191 * list is used for invalidate operation, which must look at every dquot.
193 * Unused dquots (dq_count == 0) are added to the free_dquots list when freed,
194 * and this list is searched whenever we need an available dquot. Dquots are
195 * removed from the list as soon as they are used again, and
196 * dqstats.free_dquots gives the number of dquots on the list. When
197 * dquot is invalidated it's completely released from memory.
199 * Dquots with a specific identity (device, type and id) are placed on
200 * one of the dquot_hash[] hash chains. The provides an efficient search
201 * mechanism to locate a specific dquot.
204 static LIST_HEAD(inuse_list);
205 static LIST_HEAD(free_dquots);
206 static unsigned int dq_hash_bits, dq_hash_mask;
207 static struct hlist_head *dquot_hash;
209 struct dqstats dqstats;
211 static void dqput(struct dquot *dquot);
213 static inline unsigned int
214 hashfn(const struct super_block *sb, unsigned int id, int type)
218 tmp = (((unsigned long)sb>>L1_CACHE_SHIFT) ^ id) * (MAXQUOTAS - type);
219 return (tmp + (tmp >> dq_hash_bits)) & dq_hash_mask;
223 * Following list functions expect dq_list_lock to be held
225 static inline void insert_dquot_hash(struct dquot *dquot)
227 struct hlist_head *head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id, dquot->dq_type);
228 hlist_add_head(&dquot->dq_hash, head);
231 static inline void remove_dquot_hash(struct dquot *dquot)
233 hlist_del_init(&dquot->dq_hash);
236 static inline struct dquot *find_dquot(unsigned int hashent, struct super_block *sb, unsigned int id, int type)
238 struct hlist_node *node;
241 hlist_for_each (node, dquot_hash+hashent) {
242 dquot = hlist_entry(node, struct dquot, dq_hash);
243 if (dquot->dq_sb == sb && dquot->dq_id == id && dquot->dq_type == type)
249 /* Add a dquot to the tail of the free list */
250 static inline void put_dquot_last(struct dquot *dquot)
252 list_add(&dquot->dq_free, free_dquots.prev);
253 dqstats.free_dquots++;
256 static inline void remove_free_dquot(struct dquot *dquot)
258 if (list_empty(&dquot->dq_free))
260 list_del_init(&dquot->dq_free);
261 dqstats.free_dquots--;
264 static inline void put_inuse(struct dquot *dquot)
266 /* We add to the back of inuse list so we don't have to restart
267 * when traversing this list and we block */
268 list_add(&dquot->dq_inuse, inuse_list.prev);
269 dqstats.allocated_dquots++;
272 static inline void remove_inuse(struct dquot *dquot)
274 dqstats.allocated_dquots--;
275 list_del(&dquot->dq_inuse);
278 * End of list functions needing dq_list_lock
281 static void wait_on_dquot(struct dquot *dquot)
283 down(&dquot->dq_lock);
287 #define mark_dquot_dirty(dquot) ((dquot)->dq_sb->dq_op->mark_dirty(dquot))
289 int dquot_mark_dquot_dirty(struct dquot *dquot)
291 spin_lock(&dq_list_lock);
292 if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags))
293 list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)->
294 info[dquot->dq_type].dqi_dirty_list);
295 spin_unlock(&dq_list_lock);
299 /* This function needs dq_list_lock */
300 static inline int clear_dquot_dirty(struct dquot *dquot)
302 if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags))
304 list_del_init(&dquot->dq_dirty);
308 void mark_info_dirty(struct super_block *sb, int type)
310 set_bit(DQF_INFO_DIRTY_B, &sb_dqopt(sb)->info[type].dqi_flags);
312 EXPORT_SYMBOL(mark_info_dirty);
315 * Read dquot from disk and alloc space for it
318 int dquot_acquire(struct dquot *dquot)
320 int ret = 0, ret2 = 0;
321 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
323 down(&dquot->dq_lock);
324 down(&dqopt->dqio_sem);
325 if (!test_bit(DQ_READ_B, &dquot->dq_flags))
326 ret = dqopt->ops[dquot->dq_type]->read_dqblk(dquot);
329 set_bit(DQ_READ_B, &dquot->dq_flags);
330 /* Instantiate dquot if needed */
331 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) {
332 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot);
333 /* Write the info if needed */
334 if (info_dirty(&dqopt->info[dquot->dq_type]))
335 ret2 = dqopt->ops[dquot->dq_type]->write_file_info(dquot->dq_sb, dquot->dq_type);
343 set_bit(DQ_ACTIVE_B, &dquot->dq_flags);
345 up(&dqopt->dqio_sem);
351 * Write dquot to disk
353 int dquot_commit(struct dquot *dquot)
355 int ret = 0, ret2 = 0;
356 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
358 down(&dqopt->dqio_sem);
359 spin_lock(&dq_list_lock);
360 if (!clear_dquot_dirty(dquot)) {
361 spin_unlock(&dq_list_lock);
364 spin_unlock(&dq_list_lock);
365 /* Inactive dquot can be only if there was error during read/init
366 * => we have better not writing it */
367 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
368 ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot);
369 if (info_dirty(&dqopt->info[dquot->dq_type]))
370 ret2 = dqopt->ops[dquot->dq_type]->write_file_info(dquot->dq_sb, dquot->dq_type);
375 up(&dqopt->dqio_sem);
382 int dquot_release(struct dquot *dquot)
384 int ret = 0, ret2 = 0;
385 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
387 down(&dquot->dq_lock);
388 /* Check whether we are not racing with some other dqget() */
389 if (atomic_read(&dquot->dq_count) > 1)
391 down(&dqopt->dqio_sem);
392 if (dqopt->ops[dquot->dq_type]->release_dqblk) {
393 ret = dqopt->ops[dquot->dq_type]->release_dqblk(dquot);
395 if (info_dirty(&dqopt->info[dquot->dq_type]))
396 ret2 = dqopt->ops[dquot->dq_type]->write_file_info(dquot->dq_sb, dquot->dq_type);
400 clear_bit(DQ_ACTIVE_B, &dquot->dq_flags);
401 up(&dqopt->dqio_sem);
407 /* Invalidate all dquots on the list. Note that this function is called after
408 * quota is disabled and pointers from inodes removed so there cannot be new
409 * quota users. There can still be some users of quotas due to inodes being
410 * just deleted or pruned by prune_icache() (those are not attached to any
411 * list). We have to wait for such users.
413 static void invalidate_dquots(struct super_block *sb, int type)
415 struct dquot *dquot, *tmp;
418 spin_lock(&dq_list_lock);
419 list_for_each_entry_safe(dquot, tmp, &inuse_list, dq_inuse) {
420 if (dquot->dq_sb != sb)
422 if (dquot->dq_type != type)
424 /* Wait for dquot users */
425 if (atomic_read(&dquot->dq_count)) {
428 atomic_inc(&dquot->dq_count);
429 prepare_to_wait(&dquot->dq_wait_unused, &wait,
430 TASK_UNINTERRUPTIBLE);
431 spin_unlock(&dq_list_lock);
432 /* Once dqput() wakes us up, we know it's time to free
434 * IMPORTANT: we rely on the fact that there is always
435 * at most one process waiting for dquot to free.
436 * Otherwise dq_count would be > 1 and we would never
439 if (atomic_read(&dquot->dq_count) > 1)
441 finish_wait(&dquot->dq_wait_unused, &wait);
443 /* At this moment dquot() need not exist (it could be
444 * reclaimed by prune_dqcache(). Hence we must
449 * Quota now has no users and it has been written on last
452 remove_dquot_hash(dquot);
453 remove_free_dquot(dquot);
455 kmem_cache_free(dquot_cachep, dquot);
457 spin_unlock(&dq_list_lock);
460 int vfs_quota_sync(struct super_block *sb, int type)
462 struct list_head *dirty;
464 struct quota_info *dqopt = sb_dqopt(sb);
467 down(&dqopt->dqonoff_sem);
468 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
469 if (type != -1 && cnt != type)
471 if (!sb_has_quota_enabled(sb, cnt))
473 spin_lock(&dq_list_lock);
474 dirty = &dqopt->info[cnt].dqi_dirty_list;
475 while (!list_empty(dirty)) {
476 dquot = list_entry(dirty->next, struct dquot, dq_dirty);
477 /* Dirty and inactive can be only bad dquot... */
478 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
479 clear_dquot_dirty(dquot);
482 /* Now we have active dquot from which someone is
483 * holding reference so we can safely just increase
485 atomic_inc(&dquot->dq_count);
487 spin_unlock(&dq_list_lock);
488 sb->dq_op->write_dquot(dquot);
490 spin_lock(&dq_list_lock);
492 spin_unlock(&dq_list_lock);
495 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
496 if ((cnt == type || type == -1) && sb_has_quota_enabled(sb, cnt)
497 && info_dirty(&dqopt->info[cnt]))
498 sb->dq_op->write_info(sb, cnt);
499 spin_lock(&dq_list_lock);
501 spin_unlock(&dq_list_lock);
502 up(&dqopt->dqonoff_sem);
507 /* Free unused dquots from cache */
508 static void prune_dqcache(int count)
510 struct list_head *head;
513 head = free_dquots.prev;
514 while (head != &free_dquots && count) {
515 dquot = list_entry(head, struct dquot, dq_free);
516 remove_dquot_hash(dquot);
517 remove_free_dquot(dquot);
519 kmem_cache_free(dquot_cachep, dquot);
521 head = free_dquots.prev;
526 * This is called from kswapd when we think we need some
530 static int shrink_dqcache_memory(int nr, gfp_t gfp_mask)
533 spin_lock(&dq_list_lock);
535 spin_unlock(&dq_list_lock);
537 return (dqstats.free_dquots / 100) * sysctl_vfs_cache_pressure;
541 * Put reference to dquot
542 * NOTE: If you change this function please check whether dqput_blocks() works right...
543 * MUST be called with either dqptr_sem or dqonoff_sem held
545 static void dqput(struct dquot *dquot)
549 #ifdef __DQUOT_PARANOIA
550 if (!atomic_read(&dquot->dq_count)) {
551 printk("VFS: dqput: trying to free free dquot\n");
552 printk("VFS: device %s, dquot of %s %d\n",
554 quotatypes[dquot->dq_type],
560 spin_lock(&dq_list_lock);
562 spin_unlock(&dq_list_lock);
564 spin_lock(&dq_list_lock);
565 if (atomic_read(&dquot->dq_count) > 1) {
566 /* We have more than one user... nothing to do */
567 atomic_dec(&dquot->dq_count);
568 /* Releasing dquot during quotaoff phase? */
569 if (!sb_has_quota_enabled(dquot->dq_sb, dquot->dq_type) &&
570 atomic_read(&dquot->dq_count) == 1)
571 wake_up(&dquot->dq_wait_unused);
572 spin_unlock(&dq_list_lock);
575 /* Need to release dquot? */
576 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) {
577 spin_unlock(&dq_list_lock);
578 /* Commit dquot before releasing */
579 dquot->dq_sb->dq_op->write_dquot(dquot);
582 /* Clear flag in case dquot was inactive (something bad happened) */
583 clear_dquot_dirty(dquot);
584 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
585 spin_unlock(&dq_list_lock);
586 dquot->dq_sb->dq_op->release_dquot(dquot);
589 atomic_dec(&dquot->dq_count);
590 #ifdef __DQUOT_PARANOIA
592 if (!list_empty(&dquot->dq_free))
595 put_dquot_last(dquot);
596 spin_unlock(&dq_list_lock);
599 static struct dquot *get_empty_dquot(struct super_block *sb, int type)
603 dquot = kmem_cache_alloc(dquot_cachep, SLAB_NOFS);
607 memset((caddr_t)dquot, 0, sizeof(struct dquot));
608 sema_init(&dquot->dq_lock, 1);
609 INIT_LIST_HEAD(&dquot->dq_free);
610 INIT_LIST_HEAD(&dquot->dq_inuse);
611 INIT_HLIST_NODE(&dquot->dq_hash);
612 INIT_LIST_HEAD(&dquot->dq_dirty);
613 init_waitqueue_head(&dquot->dq_wait_unused);
615 dquot->dq_type = type;
616 atomic_set(&dquot->dq_count, 1);
622 * Get reference to dquot
623 * MUST be called with either dqptr_sem or dqonoff_sem held
625 static struct dquot *dqget(struct super_block *sb, unsigned int id, int type)
627 unsigned int hashent = hashfn(sb, id, type);
628 struct dquot *dquot, *empty = NODQUOT;
630 if (!sb_has_quota_enabled(sb, type))
633 spin_lock(&dq_list_lock);
634 if ((dquot = find_dquot(hashent, sb, id, type)) == NODQUOT) {
635 if (empty == NODQUOT) {
636 spin_unlock(&dq_list_lock);
637 if ((empty = get_empty_dquot(sb, type)) == NODQUOT)
638 schedule(); /* Try to wait for a moment... */
643 /* all dquots go on the inuse_list */
645 /* hash it first so it can be found */
646 insert_dquot_hash(dquot);
648 spin_unlock(&dq_list_lock);
650 if (!atomic_read(&dquot->dq_count))
651 remove_free_dquot(dquot);
652 atomic_inc(&dquot->dq_count);
653 dqstats.cache_hits++;
655 spin_unlock(&dq_list_lock);
657 kmem_cache_free(dquot_cachep, empty);
659 /* Wait for dq_lock - after this we know that either dquot_release() is already
660 * finished or it will be canceled due to dq_count > 1 test */
661 wait_on_dquot(dquot);
662 /* Read the dquot and instantiate it (everything done only if needed) */
663 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && sb->dq_op->acquire_dquot(dquot) < 0) {
667 #ifdef __DQUOT_PARANOIA
668 if (!dquot->dq_sb) /* Has somebody invalidated entry under us? */
675 static int dqinit_needed(struct inode *inode, int type)
679 if (IS_NOQUOTA(inode))
682 return inode->i_dquot[type] == NODQUOT;
683 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
684 if (inode->i_dquot[cnt] == NODQUOT)
689 /* This routine is guarded by dqonoff_sem semaphore */
690 static void add_dquot_ref(struct super_block *sb, int type)
696 list_for_each(p, &sb->s_files) {
697 struct file *filp = list_entry(p, struct file, f_u.fu_list);
698 struct inode *inode = filp->f_dentry->d_inode;
699 if (filp->f_mode & FMODE_WRITE && dqinit_needed(inode, type)) {
700 struct dentry *dentry = dget(filp->f_dentry);
702 sb->dq_op->initialize(inode, type);
704 /* As we may have blocked we had better restart... */
711 /* Return 0 if dqput() won't block (note that 1 doesn't necessarily mean blocking) */
712 static inline int dqput_blocks(struct dquot *dquot)
714 if (atomic_read(&dquot->dq_count) <= 1)
719 /* Remove references to dquots from inode - add dquot to list for freeing if needed */
720 /* We can't race with anybody because we hold dqptr_sem for writing... */
721 int remove_inode_dquot_ref(struct inode *inode, int type, struct list_head *tofree_head)
723 struct dquot *dquot = inode->i_dquot[type];
725 inode->i_dquot[type] = NODQUOT;
726 if (dquot != NODQUOT) {
727 if (dqput_blocks(dquot)) {
728 #ifdef __DQUOT_PARANOIA
729 if (atomic_read(&dquot->dq_count) != 1)
730 printk(KERN_WARNING "VFS: Adding dquot with dq_count %d to dispose list.\n", atomic_read(&dquot->dq_count));
732 spin_lock(&dq_list_lock);
733 list_add(&dquot->dq_free, tofree_head); /* As dquot must have currently users it can't be on the free list... */
734 spin_unlock(&dq_list_lock);
738 dqput(dquot); /* We have guaranteed we won't block */
743 /* Free list of dquots - called from inode.c */
744 /* dquots are removed from inodes, no new references can be got so we are the only ones holding reference */
745 static void put_dquot_list(struct list_head *tofree_head)
747 struct list_head *act_head;
750 act_head = tofree_head->next;
751 /* So now we have dquots on the list... Just free them */
752 while (act_head != tofree_head) {
753 dquot = list_entry(act_head, struct dquot, dq_free);
754 act_head = act_head->next;
755 list_del_init(&dquot->dq_free); /* Remove dquot from the list so we won't have problems... */
760 /* Gather all references from inodes and drop them */
761 static void drop_dquot_ref(struct super_block *sb, int type)
763 LIST_HEAD(tofree_head);
765 down_write(&sb_dqopt(sb)->dqptr_sem);
766 remove_dquot_ref(sb, type, &tofree_head);
767 up_write(&sb_dqopt(sb)->dqptr_sem);
768 put_dquot_list(&tofree_head);
771 static inline void dquot_incr_inodes(struct dquot *dquot, unsigned long number)
773 dquot->dq_dqb.dqb_curinodes += number;
776 static inline void dquot_incr_space(struct dquot *dquot, qsize_t number)
778 dquot->dq_dqb.dqb_curspace += number;
781 static inline void dquot_decr_inodes(struct dquot *dquot, unsigned long number)
783 if (dquot->dq_dqb.dqb_curinodes > number)
784 dquot->dq_dqb.dqb_curinodes -= number;
786 dquot->dq_dqb.dqb_curinodes = 0;
787 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit)
788 dquot->dq_dqb.dqb_itime = (time_t) 0;
789 clear_bit(DQ_INODES_B, &dquot->dq_flags);
792 static inline void dquot_decr_space(struct dquot *dquot, qsize_t number)
794 if (dquot->dq_dqb.dqb_curspace > number)
795 dquot->dq_dqb.dqb_curspace -= number;
797 dquot->dq_dqb.dqb_curspace = 0;
798 if (toqb(dquot->dq_dqb.dqb_curspace) <= dquot->dq_dqb.dqb_bsoftlimit)
799 dquot->dq_dqb.dqb_btime = (time_t) 0;
800 clear_bit(DQ_BLKS_B, &dquot->dq_flags);
803 static int flag_print_warnings = 1;
805 static inline int need_print_warning(struct dquot *dquot)
807 if (!flag_print_warnings)
810 switch (dquot->dq_type) {
812 return current->fsuid == dquot->dq_id;
814 return in_group_p(dquot->dq_id);
819 /* Values of warnings */
822 #define ISOFTLONGWARN 2
825 #define BSOFTLONGWARN 5
828 /* Print warning to user which exceeded quota */
829 static void print_warning(struct dquot *dquot, const char warntype)
832 int flag = (warntype == BHARDWARN || warntype == BSOFTLONGWARN) ? DQ_BLKS_B :
833 ((warntype == IHARDWARN || warntype == ISOFTLONGWARN) ? DQ_INODES_B : 0);
835 if (!need_print_warning(dquot) || (flag && test_and_set_bit(flag, &dquot->dq_flags)))
838 tty_write_message(current->signal->tty, dquot->dq_sb->s_id);
839 if (warntype == ISOFTWARN || warntype == BSOFTWARN)
840 tty_write_message(current->signal->tty, ": warning, ");
842 tty_write_message(current->signal->tty, ": write failed, ");
843 tty_write_message(current->signal->tty, quotatypes[dquot->dq_type]);
846 msg = " file limit reached.\r\n";
849 msg = " file quota exceeded too long.\r\n";
852 msg = " file quota exceeded.\r\n";
855 msg = " block limit reached.\r\n";
858 msg = " block quota exceeded too long.\r\n";
861 msg = " block quota exceeded.\r\n";
864 tty_write_message(current->signal->tty, msg);
867 static inline void flush_warnings(struct dquot **dquots, char *warntype)
871 for (i = 0; i < MAXQUOTAS; i++)
872 if (dquots[i] != NODQUOT && warntype[i] != NOWARN)
873 print_warning(dquots[i], warntype[i]);
876 static inline char ignore_hardlimit(struct dquot *dquot)
878 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type];
880 return capable(CAP_SYS_RESOURCE) &&
881 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || !(info->dqi_flags & V1_DQF_RSQUASH));
884 /* needs dq_data_lock */
885 static int check_idq(struct dquot *dquot, ulong inodes, char *warntype)
888 if (inodes <= 0 || test_bit(DQ_FAKE_B, &dquot->dq_flags))
891 if (dquot->dq_dqb.dqb_ihardlimit &&
892 (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_ihardlimit &&
893 !ignore_hardlimit(dquot)) {
894 *warntype = IHARDWARN;
898 if (dquot->dq_dqb.dqb_isoftlimit &&
899 (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_isoftlimit &&
900 dquot->dq_dqb.dqb_itime && get_seconds() >= dquot->dq_dqb.dqb_itime &&
901 !ignore_hardlimit(dquot)) {
902 *warntype = ISOFTLONGWARN;
906 if (dquot->dq_dqb.dqb_isoftlimit &&
907 (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_isoftlimit &&
908 dquot->dq_dqb.dqb_itime == 0) {
909 *warntype = ISOFTWARN;
910 dquot->dq_dqb.dqb_itime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace;
916 /* needs dq_data_lock */
917 static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype)
920 if (space <= 0 || test_bit(DQ_FAKE_B, &dquot->dq_flags))
923 if (dquot->dq_dqb.dqb_bhardlimit &&
924 toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bhardlimit &&
925 !ignore_hardlimit(dquot)) {
927 *warntype = BHARDWARN;
931 if (dquot->dq_dqb.dqb_bsoftlimit &&
932 toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bsoftlimit &&
933 dquot->dq_dqb.dqb_btime && get_seconds() >= dquot->dq_dqb.dqb_btime &&
934 !ignore_hardlimit(dquot)) {
936 *warntype = BSOFTLONGWARN;
940 if (dquot->dq_dqb.dqb_bsoftlimit &&
941 toqb(dquot->dq_dqb.dqb_curspace + space) > dquot->dq_dqb.dqb_bsoftlimit &&
942 dquot->dq_dqb.dqb_btime == 0) {
944 *warntype = BSOFTWARN;
945 dquot->dq_dqb.dqb_btime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_bgrace;
949 * We don't allow preallocation to exceed softlimit so exceeding will
959 * Initialize quota pointers in inode
960 * Transaction must be started at entry
962 int dquot_initialize(struct inode *inode, int type)
967 /* First test before acquiring semaphore - solves deadlocks when we
968 * re-enter the quota code and are already holding the semaphore */
969 if (IS_NOQUOTA(inode))
971 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
972 /* Having dqptr_sem we know NOQUOTA flags can't be altered... */
973 if (IS_NOQUOTA(inode))
975 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
976 if (type != -1 && cnt != type)
978 if (inode->i_dquot[cnt] == NODQUOT) {
987 inode->i_dquot[cnt] = dqget(inode->i_sb, id, cnt);
991 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
996 * Release all quotas referenced by inode
997 * Transaction must be started at an entry
999 int dquot_drop(struct inode *inode)
1003 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1004 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1005 if (inode->i_dquot[cnt] != NODQUOT) {
1006 dqput(inode->i_dquot[cnt]);
1007 inode->i_dquot[cnt] = NODQUOT;
1010 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1015 * Following four functions update i_blocks+i_bytes fields and
1016 * quota information (together with appropriate checks)
1017 * NOTE: We absolutely rely on the fact that caller dirties
1018 * the inode (usually macros in quotaops.h care about this) and
1019 * holds a handle for the current transaction so that dquot write and
1020 * inode write go into the same transaction.
1024 * This operation can block, but only after everything is updated
1026 int dquot_alloc_space(struct inode *inode, qsize_t number, int warn)
1028 int cnt, ret = NO_QUOTA;
1029 char warntype[MAXQUOTAS];
1031 /* First test before acquiring semaphore - solves deadlocks when we
1032 * re-enter the quota code and are already holding the semaphore */
1033 if (IS_NOQUOTA(inode)) {
1035 inode_add_bytes(inode, number);
1038 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1039 warntype[cnt] = NOWARN;
1041 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1042 if (IS_NOQUOTA(inode)) { /* Now we can do reliable test... */
1043 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1046 spin_lock(&dq_data_lock);
1047 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1048 if (inode->i_dquot[cnt] == NODQUOT)
1050 if (check_bdq(inode->i_dquot[cnt], number, warn, warntype+cnt) == NO_QUOTA)
1053 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1054 if (inode->i_dquot[cnt] == NODQUOT)
1056 dquot_incr_space(inode->i_dquot[cnt], number);
1058 inode_add_bytes(inode, number);
1061 spin_unlock(&dq_data_lock);
1062 if (ret == QUOTA_OK)
1063 /* Dirtify all the dquots - this can block when journalling */
1064 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1065 if (inode->i_dquot[cnt])
1066 mark_dquot_dirty(inode->i_dquot[cnt]);
1067 flush_warnings(inode->i_dquot, warntype);
1068 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1073 * This operation can block, but only after everything is updated
1075 int dquot_alloc_inode(const struct inode *inode, unsigned long number)
1077 int cnt, ret = NO_QUOTA;
1078 char warntype[MAXQUOTAS];
1080 /* First test before acquiring semaphore - solves deadlocks when we
1081 * re-enter the quota code and are already holding the semaphore */
1082 if (IS_NOQUOTA(inode))
1084 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1085 warntype[cnt] = NOWARN;
1086 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1087 if (IS_NOQUOTA(inode)) {
1088 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1091 spin_lock(&dq_data_lock);
1092 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1093 if (inode->i_dquot[cnt] == NODQUOT)
1095 if (check_idq(inode->i_dquot[cnt], number, warntype+cnt) == NO_QUOTA)
1099 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1100 if (inode->i_dquot[cnt] == NODQUOT)
1102 dquot_incr_inodes(inode->i_dquot[cnt], number);
1106 spin_unlock(&dq_data_lock);
1107 if (ret == QUOTA_OK)
1108 /* Dirtify all the dquots - this can block when journalling */
1109 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1110 if (inode->i_dquot[cnt])
1111 mark_dquot_dirty(inode->i_dquot[cnt]);
1112 flush_warnings((struct dquot **)inode->i_dquot, warntype);
1113 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1118 * This operation can block, but only after everything is updated
1120 int dquot_free_space(struct inode *inode, qsize_t number)
1124 /* First test before acquiring semaphore - solves deadlocks when we
1125 * re-enter the quota code and are already holding the semaphore */
1126 if (IS_NOQUOTA(inode)) {
1128 inode_sub_bytes(inode, number);
1131 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1132 /* Now recheck reliably when holding dqptr_sem */
1133 if (IS_NOQUOTA(inode)) {
1134 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1137 spin_lock(&dq_data_lock);
1138 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1139 if (inode->i_dquot[cnt] == NODQUOT)
1141 dquot_decr_space(inode->i_dquot[cnt], number);
1143 inode_sub_bytes(inode, number);
1144 spin_unlock(&dq_data_lock);
1145 /* Dirtify all the dquots - this can block when journalling */
1146 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1147 if (inode->i_dquot[cnt])
1148 mark_dquot_dirty(inode->i_dquot[cnt]);
1149 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1154 * This operation can block, but only after everything is updated
1156 int dquot_free_inode(const struct inode *inode, unsigned long number)
1160 /* First test before acquiring semaphore - solves deadlocks when we
1161 * re-enter the quota code and are already holding the semaphore */
1162 if (IS_NOQUOTA(inode))
1164 down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1165 /* Now recheck reliably when holding dqptr_sem */
1166 if (IS_NOQUOTA(inode)) {
1167 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1170 spin_lock(&dq_data_lock);
1171 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1172 if (inode->i_dquot[cnt] == NODQUOT)
1174 dquot_decr_inodes(inode->i_dquot[cnt], number);
1176 spin_unlock(&dq_data_lock);
1177 /* Dirtify all the dquots - this can block when journalling */
1178 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1179 if (inode->i_dquot[cnt])
1180 mark_dquot_dirty(inode->i_dquot[cnt]);
1181 up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
1186 * Transfer the number of inode and blocks from one diskquota to an other.
1188 * This operation can block, but only after everything is updated
1189 * A transaction must be started when entering this function.
1191 int dquot_transfer(struct inode *inode, struct iattr *iattr)
1194 struct dquot *transfer_from[MAXQUOTAS];
1195 struct dquot *transfer_to[MAXQUOTAS];
1196 int cnt, ret = NO_QUOTA, chuid = (iattr->ia_valid & ATTR_UID) && inode->i_uid != iattr->ia_uid,
1197 chgid = (iattr->ia_valid & ATTR_GID) && inode->i_gid != iattr->ia_gid;
1198 char warntype[MAXQUOTAS];
1200 /* First test before acquiring semaphore - solves deadlocks when we
1201 * re-enter the quota code and are already holding the semaphore */
1202 if (IS_NOQUOTA(inode))
1204 /* Clear the arrays */
1205 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1206 transfer_to[cnt] = transfer_from[cnt] = NODQUOT;
1207 warntype[cnt] = NOWARN;
1209 down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1210 /* Now recheck reliably when holding dqptr_sem */
1211 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */
1212 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1215 /* First build the transfer_to list - here we can block on
1216 * reading/instantiating of dquots. We know that the transaction for
1217 * us was already started so we don't violate lock ranking here */
1218 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1223 transfer_to[cnt] = dqget(inode->i_sb, iattr->ia_uid, cnt);
1228 transfer_to[cnt] = dqget(inode->i_sb, iattr->ia_gid, cnt);
1232 spin_lock(&dq_data_lock);
1233 space = inode_get_bytes(inode);
1234 /* Build the transfer_from list and check the limits */
1235 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1236 if (transfer_to[cnt] == NODQUOT)
1238 transfer_from[cnt] = inode->i_dquot[cnt];
1239 if (check_idq(transfer_to[cnt], 1, warntype+cnt) == NO_QUOTA ||
1240 check_bdq(transfer_to[cnt], space, 0, warntype+cnt) == NO_QUOTA)
1245 * Finally perform the needed transfer from transfer_from to transfer_to
1247 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1249 * Skip changes for same uid or gid or for turned off quota-type.
1251 if (transfer_to[cnt] == NODQUOT)
1254 /* Due to IO error we might not have transfer_from[] structure */
1255 if (transfer_from[cnt]) {
1256 dquot_decr_inodes(transfer_from[cnt], 1);
1257 dquot_decr_space(transfer_from[cnt], space);
1260 dquot_incr_inodes(transfer_to[cnt], 1);
1261 dquot_incr_space(transfer_to[cnt], space);
1263 inode->i_dquot[cnt] = transfer_to[cnt];
1267 spin_unlock(&dq_data_lock);
1268 /* Dirtify all the dquots - this can block when journalling */
1269 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1270 if (transfer_from[cnt])
1271 mark_dquot_dirty(transfer_from[cnt]);
1272 if (transfer_to[cnt])
1273 mark_dquot_dirty(transfer_to[cnt]);
1275 flush_warnings(transfer_to, warntype);
1277 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1278 if (ret == QUOTA_OK && transfer_from[cnt] != NODQUOT)
1279 dqput(transfer_from[cnt]);
1280 if (ret == NO_QUOTA && transfer_to[cnt] != NODQUOT)
1281 dqput(transfer_to[cnt]);
1283 up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
1288 * Write info of quota file to disk
1290 int dquot_commit_info(struct super_block *sb, int type)
1293 struct quota_info *dqopt = sb_dqopt(sb);
1295 down(&dqopt->dqio_sem);
1296 ret = dqopt->ops[type]->write_file_info(sb, type);
1297 up(&dqopt->dqio_sem);
1302 * Definitions of diskquota operations.
1304 struct dquot_operations dquot_operations = {
1305 .initialize = dquot_initialize,
1307 .alloc_space = dquot_alloc_space,
1308 .alloc_inode = dquot_alloc_inode,
1309 .free_space = dquot_free_space,
1310 .free_inode = dquot_free_inode,
1311 .transfer = dquot_transfer,
1312 .write_dquot = dquot_commit,
1313 .acquire_dquot = dquot_acquire,
1314 .release_dquot = dquot_release,
1315 .mark_dirty = dquot_mark_dquot_dirty,
1316 .write_info = dquot_commit_info
1319 static inline void set_enable_flags(struct quota_info *dqopt, int type)
1323 dqopt->flags |= DQUOT_USR_ENABLED;
1326 dqopt->flags |= DQUOT_GRP_ENABLED;
1331 static inline void reset_enable_flags(struct quota_info *dqopt, int type)
1335 dqopt->flags &= ~DQUOT_USR_ENABLED;
1338 dqopt->flags &= ~DQUOT_GRP_ENABLED;
1344 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount)
1346 int vfs_quota_off(struct super_block *sb, int type)
1349 struct quota_info *dqopt = sb_dqopt(sb);
1350 struct inode *toputinode[MAXQUOTAS];
1352 /* We need to serialize quota_off() for device */
1353 down(&dqopt->dqonoff_sem);
1354 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1355 toputinode[cnt] = NULL;
1356 if (type != -1 && cnt != type)
1358 if (!sb_has_quota_enabled(sb, cnt))
1360 reset_enable_flags(dqopt, cnt);
1362 /* Note: these are blocking operations */
1363 drop_dquot_ref(sb, cnt);
1364 invalidate_dquots(sb, cnt);
1366 * Now all dquots should be invalidated, all writes done so we should be only
1367 * users of the info. No locks needed.
1369 if (info_dirty(&dqopt->info[cnt]))
1370 sb->dq_op->write_info(sb, cnt);
1371 if (dqopt->ops[cnt]->free_file_info)
1372 dqopt->ops[cnt]->free_file_info(sb, cnt);
1373 put_quota_format(dqopt->info[cnt].dqi_format);
1375 toputinode[cnt] = dqopt->files[cnt];
1376 dqopt->files[cnt] = NULL;
1377 dqopt->info[cnt].dqi_flags = 0;
1378 dqopt->info[cnt].dqi_igrace = 0;
1379 dqopt->info[cnt].dqi_bgrace = 0;
1380 dqopt->ops[cnt] = NULL;
1382 up(&dqopt->dqonoff_sem);
1383 /* Sync the superblock so that buffers with quota data are written to
1384 * disk (and so userspace sees correct data afterwards). */
1385 if (sb->s_op->sync_fs)
1386 sb->s_op->sync_fs(sb, 1);
1387 sync_blockdev(sb->s_bdev);
1388 /* Now the quota files are just ordinary files and we can set the
1389 * inode flags back. Moreover we discard the pagecache so that
1390 * userspace sees the writes we did bypassing the pagecache. We
1391 * must also discard the blockdev buffers so that we see the
1392 * changes done by userspace on the next quotaon() */
1393 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1394 if (toputinode[cnt]) {
1395 down(&dqopt->dqonoff_sem);
1396 /* If quota was reenabled in the meantime, we have
1398 if (!sb_has_quota_enabled(sb, cnt)) {
1399 mutex_lock(&toputinode[cnt]->i_mutex);
1400 toputinode[cnt]->i_flags &= ~(S_IMMUTABLE |
1401 S_NOATIME | S_NOQUOTA);
1402 truncate_inode_pages(&toputinode[cnt]->i_data, 0);
1403 mutex_unlock(&toputinode[cnt]->i_mutex);
1404 mark_inode_dirty(toputinode[cnt]);
1405 iput(toputinode[cnt]);
1407 up(&dqopt->dqonoff_sem);
1410 invalidate_bdev(sb->s_bdev, 0);
1415 * Turn quotas on on a device
1418 /* Helper function when we already have the inode */
1419 static int vfs_quota_on_inode(struct inode *inode, int type, int format_id)
1421 struct quota_format_type *fmt = find_quota_format(format_id);
1422 struct super_block *sb = inode->i_sb;
1423 struct quota_info *dqopt = sb_dqopt(sb);
1429 if (!S_ISREG(inode->i_mode)) {
1433 if (IS_RDONLY(inode)) {
1437 if (!sb->s_op->quota_write || !sb->s_op->quota_read) {
1442 /* As we bypass the pagecache we must now flush the inode so that
1443 * we see all the changes from userspace... */
1444 write_inode_now(inode, 1);
1445 /* And now flush the block cache so that kernel sees the changes */
1446 invalidate_bdev(sb->s_bdev, 0);
1447 mutex_lock(&inode->i_mutex);
1448 down(&dqopt->dqonoff_sem);
1449 if (sb_has_quota_enabled(sb, type)) {
1453 /* We don't want quota and atime on quota files (deadlocks possible)
1454 * Also nobody should write to the file - we use special IO operations
1455 * which ignore the immutable bit. */
1456 down_write(&dqopt->dqptr_sem);
1457 oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | S_NOQUOTA);
1458 inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE;
1459 up_write(&dqopt->dqptr_sem);
1460 sb->dq_op->drop(inode);
1463 dqopt->files[type] = igrab(inode);
1464 if (!dqopt->files[type])
1467 if (!fmt->qf_ops->check_quota_file(sb, type))
1470 dqopt->ops[type] = fmt->qf_ops;
1471 dqopt->info[type].dqi_format = fmt;
1472 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list);
1473 down(&dqopt->dqio_sem);
1474 if ((error = dqopt->ops[type]->read_file_info(sb, type)) < 0) {
1475 up(&dqopt->dqio_sem);
1478 up(&dqopt->dqio_sem);
1479 mutex_unlock(&inode->i_mutex);
1480 set_enable_flags(dqopt, type);
1482 add_dquot_ref(sb, type);
1483 up(&dqopt->dqonoff_sem);
1488 dqopt->files[type] = NULL;
1491 up(&dqopt->dqonoff_sem);
1492 if (oldflags != -1) {
1493 down_write(&dqopt->dqptr_sem);
1494 /* Set the flags back (in the case of accidental quotaon()
1495 * on a wrong file we don't want to mess up the flags) */
1496 inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE);
1497 inode->i_flags |= oldflags;
1498 up_write(&dqopt->dqptr_sem);
1500 mutex_unlock(&inode->i_mutex);
1502 put_quota_format(fmt);
1507 /* Actual function called from quotactl() */
1508 int vfs_quota_on(struct super_block *sb, int type, int format_id, char *path)
1510 struct nameidata nd;
1513 error = path_lookup(path, LOOKUP_FOLLOW, &nd);
1516 error = security_quota_on(nd.dentry);
1519 /* Quota file not on the same filesystem? */
1520 if (nd.mnt->mnt_sb != sb)
1523 error = vfs_quota_on_inode(nd.dentry->d_inode, type, format_id);
1530 * This function is used when filesystem needs to initialize quotas
1531 * during mount time.
1533 int vfs_quota_on_mount(struct super_block *sb, char *qf_name,
1534 int format_id, int type)
1536 struct dentry *dentry;
1539 dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name));
1541 return PTR_ERR(dentry);
1543 if (!dentry->d_inode) {
1548 error = security_quota_on(dentry);
1550 error = vfs_quota_on_inode(dentry->d_inode, type, format_id);
1557 /* Generic routine for getting common part of quota structure */
1558 static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di)
1560 struct mem_dqblk *dm = &dquot->dq_dqb;
1562 spin_lock(&dq_data_lock);
1563 di->dqb_bhardlimit = dm->dqb_bhardlimit;
1564 di->dqb_bsoftlimit = dm->dqb_bsoftlimit;
1565 di->dqb_curspace = dm->dqb_curspace;
1566 di->dqb_ihardlimit = dm->dqb_ihardlimit;
1567 di->dqb_isoftlimit = dm->dqb_isoftlimit;
1568 di->dqb_curinodes = dm->dqb_curinodes;
1569 di->dqb_btime = dm->dqb_btime;
1570 di->dqb_itime = dm->dqb_itime;
1571 di->dqb_valid = QIF_ALL;
1572 spin_unlock(&dq_data_lock);
1575 int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di)
1577 struct dquot *dquot;
1579 down(&sb_dqopt(sb)->dqonoff_sem);
1580 if (!(dquot = dqget(sb, id, type))) {
1581 up(&sb_dqopt(sb)->dqonoff_sem);
1584 do_get_dqblk(dquot, di);
1586 up(&sb_dqopt(sb)->dqonoff_sem);
1590 /* Generic routine for setting common part of quota structure */
1591 static void do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
1593 struct mem_dqblk *dm = &dquot->dq_dqb;
1594 int check_blim = 0, check_ilim = 0;
1596 spin_lock(&dq_data_lock);
1597 if (di->dqb_valid & QIF_SPACE) {
1598 dm->dqb_curspace = di->dqb_curspace;
1601 if (di->dqb_valid & QIF_BLIMITS) {
1602 dm->dqb_bsoftlimit = di->dqb_bsoftlimit;
1603 dm->dqb_bhardlimit = di->dqb_bhardlimit;
1606 if (di->dqb_valid & QIF_INODES) {
1607 dm->dqb_curinodes = di->dqb_curinodes;
1610 if (di->dqb_valid & QIF_ILIMITS) {
1611 dm->dqb_isoftlimit = di->dqb_isoftlimit;
1612 dm->dqb_ihardlimit = di->dqb_ihardlimit;
1615 if (di->dqb_valid & QIF_BTIME)
1616 dm->dqb_btime = di->dqb_btime;
1617 if (di->dqb_valid & QIF_ITIME)
1618 dm->dqb_itime = di->dqb_itime;
1621 if (!dm->dqb_bsoftlimit || toqb(dm->dqb_curspace) < dm->dqb_bsoftlimit) {
1623 clear_bit(DQ_BLKS_B, &dquot->dq_flags);
1625 else if (!(di->dqb_valid & QIF_BTIME)) /* Set grace only if user hasn't provided his own... */
1626 dm->dqb_btime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_bgrace;
1629 if (!dm->dqb_isoftlimit || dm->dqb_curinodes < dm->dqb_isoftlimit) {
1631 clear_bit(DQ_INODES_B, &dquot->dq_flags);
1633 else if (!(di->dqb_valid & QIF_ITIME)) /* Set grace only if user hasn't provided his own... */
1634 dm->dqb_itime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace;
1636 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || dm->dqb_isoftlimit)
1637 clear_bit(DQ_FAKE_B, &dquot->dq_flags);
1639 set_bit(DQ_FAKE_B, &dquot->dq_flags);
1640 spin_unlock(&dq_data_lock);
1641 mark_dquot_dirty(dquot);
1644 int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di)
1646 struct dquot *dquot;
1648 down(&sb_dqopt(sb)->dqonoff_sem);
1649 if (!(dquot = dqget(sb, id, type))) {
1650 up(&sb_dqopt(sb)->dqonoff_sem);
1653 do_set_dqblk(dquot, di);
1655 up(&sb_dqopt(sb)->dqonoff_sem);
1659 /* Generic routine for getting common part of quota file information */
1660 int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii)
1662 struct mem_dqinfo *mi;
1664 down(&sb_dqopt(sb)->dqonoff_sem);
1665 if (!sb_has_quota_enabled(sb, type)) {
1666 up(&sb_dqopt(sb)->dqonoff_sem);
1669 mi = sb_dqopt(sb)->info + type;
1670 spin_lock(&dq_data_lock);
1671 ii->dqi_bgrace = mi->dqi_bgrace;
1672 ii->dqi_igrace = mi->dqi_igrace;
1673 ii->dqi_flags = mi->dqi_flags & DQF_MASK;
1674 ii->dqi_valid = IIF_ALL;
1675 spin_unlock(&dq_data_lock);
1676 up(&sb_dqopt(sb)->dqonoff_sem);
1680 /* Generic routine for setting common part of quota file information */
1681 int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii)
1683 struct mem_dqinfo *mi;
1685 down(&sb_dqopt(sb)->dqonoff_sem);
1686 if (!sb_has_quota_enabled(sb, type)) {
1687 up(&sb_dqopt(sb)->dqonoff_sem);
1690 mi = sb_dqopt(sb)->info + type;
1691 spin_lock(&dq_data_lock);
1692 if (ii->dqi_valid & IIF_BGRACE)
1693 mi->dqi_bgrace = ii->dqi_bgrace;
1694 if (ii->dqi_valid & IIF_IGRACE)
1695 mi->dqi_igrace = ii->dqi_igrace;
1696 if (ii->dqi_valid & IIF_FLAGS)
1697 mi->dqi_flags = (mi->dqi_flags & ~DQF_MASK) | (ii->dqi_flags & DQF_MASK);
1698 spin_unlock(&dq_data_lock);
1699 mark_info_dirty(sb, type);
1700 /* Force write to disk */
1701 sb->dq_op->write_info(sb, type);
1702 up(&sb_dqopt(sb)->dqonoff_sem);
1706 struct quotactl_ops vfs_quotactl_ops = {
1707 .quota_on = vfs_quota_on,
1708 .quota_off = vfs_quota_off,
1709 .quota_sync = vfs_quota_sync,
1710 .get_info = vfs_get_dqinfo,
1711 .set_info = vfs_set_dqinfo,
1712 .get_dqblk = vfs_get_dqblk,
1713 .set_dqblk = vfs_set_dqblk
1716 static ctl_table fs_dqstats_table[] = {
1718 .ctl_name = FS_DQ_LOOKUPS,
1719 .procname = "lookups",
1720 .data = &dqstats.lookups,
1721 .maxlen = sizeof(int),
1723 .proc_handler = &proc_dointvec,
1726 .ctl_name = FS_DQ_DROPS,
1727 .procname = "drops",
1728 .data = &dqstats.drops,
1729 .maxlen = sizeof(int),
1731 .proc_handler = &proc_dointvec,
1734 .ctl_name = FS_DQ_READS,
1735 .procname = "reads",
1736 .data = &dqstats.reads,
1737 .maxlen = sizeof(int),
1739 .proc_handler = &proc_dointvec,
1742 .ctl_name = FS_DQ_WRITES,
1743 .procname = "writes",
1744 .data = &dqstats.writes,
1745 .maxlen = sizeof(int),
1747 .proc_handler = &proc_dointvec,
1750 .ctl_name = FS_DQ_CACHE_HITS,
1751 .procname = "cache_hits",
1752 .data = &dqstats.cache_hits,
1753 .maxlen = sizeof(int),
1755 .proc_handler = &proc_dointvec,
1758 .ctl_name = FS_DQ_ALLOCATED,
1759 .procname = "allocated_dquots",
1760 .data = &dqstats.allocated_dquots,
1761 .maxlen = sizeof(int),
1763 .proc_handler = &proc_dointvec,
1766 .ctl_name = FS_DQ_FREE,
1767 .procname = "free_dquots",
1768 .data = &dqstats.free_dquots,
1769 .maxlen = sizeof(int),
1771 .proc_handler = &proc_dointvec,
1774 .ctl_name = FS_DQ_SYNCS,
1775 .procname = "syncs",
1776 .data = &dqstats.syncs,
1777 .maxlen = sizeof(int),
1779 .proc_handler = &proc_dointvec,
1782 .ctl_name = FS_DQ_WARNINGS,
1783 .procname = "warnings",
1784 .data = &flag_print_warnings,
1785 .maxlen = sizeof(int),
1787 .proc_handler = &proc_dointvec,
1792 static ctl_table fs_table[] = {
1794 .ctl_name = FS_DQSTATS,
1795 .procname = "quota",
1797 .child = fs_dqstats_table,
1802 static ctl_table sys_table[] = {
1812 static int __init dquot_init(void)
1815 unsigned long nr_hash, order;
1817 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__);
1819 register_sysctl_table(sys_table, 0);
1821 dquot_cachep = kmem_cache_create("dquot",
1822 sizeof(struct dquot), sizeof(unsigned long) * 4,
1823 SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|SLAB_PANIC,
1827 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order);
1829 panic("Cannot create dquot hash table");
1831 /* Find power-of-two hlist_heads which can fit into allocation */
1832 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head);
1836 } while (nr_hash >> dq_hash_bits);
1839 nr_hash = 1UL << dq_hash_bits;
1840 dq_hash_mask = nr_hash - 1;
1841 for (i = 0; i < nr_hash; i++)
1842 INIT_HLIST_HEAD(dquot_hash + i);
1844 printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n",
1845 nr_hash, order, (PAGE_SIZE << order));
1847 set_shrinker(DEFAULT_SEEKS, shrink_dqcache_memory);
1851 module_init(dquot_init);
1853 EXPORT_SYMBOL(register_quota_format);
1854 EXPORT_SYMBOL(unregister_quota_format);
1855 EXPORT_SYMBOL(dqstats);
1856 EXPORT_SYMBOL(dq_data_lock);
1857 EXPORT_SYMBOL(vfs_quota_on);
1858 EXPORT_SYMBOL(vfs_quota_on_mount);
1859 EXPORT_SYMBOL(vfs_quota_off);
1860 EXPORT_SYMBOL(vfs_quota_sync);
1861 EXPORT_SYMBOL(vfs_get_dqinfo);
1862 EXPORT_SYMBOL(vfs_set_dqinfo);
1863 EXPORT_SYMBOL(vfs_get_dqblk);
1864 EXPORT_SYMBOL(vfs_set_dqblk);
1865 EXPORT_SYMBOL(dquot_commit);
1866 EXPORT_SYMBOL(dquot_commit_info);
1867 EXPORT_SYMBOL(dquot_acquire);
1868 EXPORT_SYMBOL(dquot_release);
1869 EXPORT_SYMBOL(dquot_mark_dquot_dirty);
1870 EXPORT_SYMBOL(dquot_initialize);
1871 EXPORT_SYMBOL(dquot_drop);
1872 EXPORT_SYMBOL(dquot_alloc_space);
1873 EXPORT_SYMBOL(dquot_alloc_inode);
1874 EXPORT_SYMBOL(dquot_free_space);
1875 EXPORT_SYMBOL(dquot_free_inode);
1876 EXPORT_SYMBOL(dquot_transfer);