1 // SPDX-License-Identifier: GPL-2.0
3 * Implementation of the diskquota system for the LINUX operating system. QUOTA
4 * is implemented using the BSD system call interface as the means of
5 * communication with the user level. This file contains the generic routines
6 * called by the different filesystems on allocation of an inode or block.
7 * These routines take care of the administration needed to have a consistent
8 * diskquota tracking system. The ideas of both user and group quotas are based
9 * on the Melbourne quota system as used on BSD derived systems. The internal
10 * implementation is based on one of the several variants of the LINUX
11 * inode-subsystem with added complexity of the diskquota system.
13 * Author: Marco van Wieringen <mvw@planets.elm.net>
15 * Fixes: Dmitry Gorodchanin <pgmdsg@ibi.com>, 11 Feb 96
17 * Revised list management to avoid races
18 * -- Bill Hawes, <whawes@star.net>, 9/98
20 * Fixed races in dquot_transfer(), dqget() and dquot_alloc_...().
21 * As the consequence the locking was moved from dquot_decr_...(),
22 * dquot_incr_...() to calling functions.
23 * invalidate_dquots() now writes modified dquots.
24 * Serialized quota_off() and quota_on() for mount point.
25 * Fixed a few bugs in grow_dquots().
26 * Fixed deadlock in write_dquot() - we no longer account quotas on
28 * remove_dquot_ref() moved to inode.c - it now traverses through inodes
29 * add_dquot_ref() restarts after blocking
30 * Added check for bogus uid and fixed check for group in quotactl.
31 * Jan Kara, <jack@suse.cz>, sponsored by SuSE CR, 10-11/99
33 * Used struct list_head instead of own list struct
34 * Invalidation of referenced dquots is no longer possible
35 * Improved free_dquots list management
36 * Quota and i_blocks are now updated in one place to avoid races
37 * Warnings are now delayed so we won't block in critical section
38 * Write updated not to require dquot lock
39 * Jan Kara, <jack@suse.cz>, 9/2000
41 * Added dynamic quota structure allocation
42 * Jan Kara <jack@suse.cz> 12/2000
44 * Rewritten quota interface. Implemented new quota format and
45 * formats registering.
46 * Jan Kara, <jack@suse.cz>, 2001,2002
49 * Jan Kara, <jack@suse.cz>, 10/2002
51 * Added journalled quota support, fix lock inversion problems
52 * Jan Kara, <jack@suse.cz>, 2003,2004
54 * (C) Copyright 1994 - 1997 Marco van Wieringen
57 #include <linux/errno.h>
58 #include <linux/kernel.h>
60 #include <linux/mount.h>
62 #include <linux/time.h>
63 #include <linux/types.h>
64 #include <linux/string.h>
65 #include <linux/fcntl.h>
66 #include <linux/stat.h>
67 #include <linux/tty.h>
68 #include <linux/file.h>
69 #include <linux/slab.h>
70 #include <linux/sysctl.h>
71 #include <linux/init.h>
72 #include <linux/module.h>
73 #include <linux/proc_fs.h>
74 #include <linux/security.h>
75 #include <linux/sched.h>
76 #include <linux/cred.h>
77 #include <linux/kmod.h>
78 #include <linux/namei.h>
79 #include <linux/capability.h>
80 #include <linux/quotaops.h>
81 #include <linux/blkdev.h>
82 #include <linux/sched/mm.h>
83 #include "../internal.h" /* ugh */
85 #include <linux/uaccess.h>
88 * There are five quota SMP locks:
89 * * dq_list_lock protects all lists with quotas and quota formats.
90 * * dquot->dq_dqb_lock protects data from dq_dqb
91 * * inode->i_lock protects inode->i_blocks, i_bytes and also guards
92 * consistency of dquot->dq_dqb with inode->i_blocks, i_bytes so that
93 * dquot_transfer() can stabilize amount it transfers
94 * * dq_data_lock protects mem_dqinfo structures and modifications of dquot
95 * pointers in the inode
96 * * dq_state_lock protects modifications of quota state (on quotaon and
97 * quotaoff) and readers who care about latest values take it as well.
99 * The spinlock ordering is hence:
100 * dq_data_lock > dq_list_lock > i_lock > dquot->dq_dqb_lock,
101 * dq_list_lock > dq_state_lock
103 * Note that some things (eg. sb pointer, type, id) doesn't change during
104 * the life of the dquot structure and so needn't to be protected by a lock
106 * Operation accessing dquots via inode pointers are protected by dquot_srcu.
107 * Operation of reading pointer needs srcu_read_lock(&dquot_srcu), and
108 * synchronize_srcu(&dquot_srcu) is called after clearing pointers from
109 * inode and before dropping dquot references to avoid use of dquots after
110 * they are freed. dq_data_lock is used to serialize the pointer setting and
111 * clearing operations.
112 * Special care needs to be taken about S_NOQUOTA inode flag (marking that
113 * inode is a quota file). Functions adding pointers from inode to dquots have
114 * to check this flag under dq_data_lock and then (if S_NOQUOTA is not set) they
115 * have to do all pointer modifications before dropping dq_data_lock. This makes
116 * sure they cannot race with quotaon which first sets S_NOQUOTA flag and
117 * then drops all pointers to dquots from an inode.
119 * Each dquot has its dq_lock mutex. Dquot is locked when it is being read to
120 * memory (or space for it is being allocated) on the first dqget(), when it is
121 * being written out, and when it is being released on the last dqput(). The
122 * allocation and release operations are serialized by the dq_lock and by
123 * checking the use count in dquot_release().
125 * Lock ordering (including related VFS locks) is the following:
126 * s_umount > i_mutex > journal_lock > dquot->dq_lock > dqio_sem
129 static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_list_lock);
130 static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_state_lock);
131 __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_data_lock);
132 EXPORT_SYMBOL(dq_data_lock);
133 DEFINE_STATIC_SRCU(dquot_srcu);
135 static DECLARE_WAIT_QUEUE_HEAD(dquot_ref_wq);
137 void __quota_error(struct super_block *sb, const char *func,
138 const char *fmt, ...)
140 if (printk_ratelimit()) {
142 struct va_format vaf;
149 printk(KERN_ERR "Quota error (device %s): %s: %pV\n",
150 sb->s_id, func, &vaf);
155 EXPORT_SYMBOL(__quota_error);
157 #if defined(CONFIG_QUOTA_DEBUG) || defined(CONFIG_PRINT_QUOTA_WARNING)
158 static char *quotatypes[] = INITQFNAMES;
160 static struct quota_format_type *quota_formats; /* List of registered formats */
161 static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES;
163 /* SLAB cache for dquot structures */
164 static struct kmem_cache *dquot_cachep;
166 int register_quota_format(struct quota_format_type *fmt)
168 spin_lock(&dq_list_lock);
169 fmt->qf_next = quota_formats;
171 spin_unlock(&dq_list_lock);
174 EXPORT_SYMBOL(register_quota_format);
176 void unregister_quota_format(struct quota_format_type *fmt)
178 struct quota_format_type **actqf;
180 spin_lock(&dq_list_lock);
181 for (actqf = "a_formats; *actqf && *actqf != fmt;
182 actqf = &(*actqf)->qf_next)
185 *actqf = (*actqf)->qf_next;
186 spin_unlock(&dq_list_lock);
188 EXPORT_SYMBOL(unregister_quota_format);
190 static struct quota_format_type *find_quota_format(int id)
192 struct quota_format_type *actqf;
194 spin_lock(&dq_list_lock);
195 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id;
196 actqf = actqf->qf_next)
198 if (!actqf || !try_module_get(actqf->qf_owner)) {
201 spin_unlock(&dq_list_lock);
203 for (qm = 0; module_names[qm].qm_fmt_id &&
204 module_names[qm].qm_fmt_id != id; qm++)
206 if (!module_names[qm].qm_fmt_id ||
207 request_module(module_names[qm].qm_mod_name))
210 spin_lock(&dq_list_lock);
211 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id;
212 actqf = actqf->qf_next)
214 if (actqf && !try_module_get(actqf->qf_owner))
217 spin_unlock(&dq_list_lock);
221 static void put_quota_format(struct quota_format_type *fmt)
223 module_put(fmt->qf_owner);
227 * Dquot List Management:
228 * The quota code uses five lists for dquot management: the inuse_list,
229 * releasing_dquots, free_dquots, dqi_dirty_list, and dquot_hash[] array.
230 * A single dquot structure may be on some of those lists, depending on
233 * All dquots are placed to the end of inuse_list when first created, and this
234 * list is used for invalidate operation, which must look at every dquot.
236 * When the last reference of a dquot will be dropped, the dquot will be
237 * added to releasing_dquots. We'd then queue work item which would call
238 * synchronize_srcu() and after that perform the final cleanup of all the
239 * dquots on the list. Both releasing_dquots and free_dquots use the
240 * dq_free list_head in the dquot struct. When a dquot is removed from
241 * releasing_dquots, a reference count is always subtracted, and if
242 * dq_count == 0 at that point, the dquot will be added to the free_dquots.
244 * Unused dquots (dq_count == 0) are added to the free_dquots list when freed,
245 * and this list is searched whenever we need an available dquot. Dquots are
246 * removed from the list as soon as they are used again, and
247 * dqstats.free_dquots gives the number of dquots on the list. When
248 * dquot is invalidated it's completely released from memory.
250 * Dirty dquots are added to the dqi_dirty_list of quota_info when mark
251 * dirtied, and this list is searched when writing dirty dquots back to
252 * quota file. Note that some filesystems do dirty dquot tracking on their
253 * own (e.g. in a journal) and thus don't use dqi_dirty_list.
255 * Dquots with a specific identity (device, type and id) are placed on
256 * one of the dquot_hash[] hash chains. The provides an efficient search
257 * mechanism to locate a specific dquot.
260 static LIST_HEAD(inuse_list);
261 static LIST_HEAD(free_dquots);
262 static LIST_HEAD(releasing_dquots);
263 static unsigned int dq_hash_bits, dq_hash_mask;
264 static struct hlist_head *dquot_hash;
266 struct dqstats dqstats;
267 EXPORT_SYMBOL(dqstats);
269 static qsize_t inode_get_rsv_space(struct inode *inode);
270 static qsize_t __inode_get_rsv_space(struct inode *inode);
271 static int __dquot_initialize(struct inode *inode, int type);
273 static void quota_release_workfn(struct work_struct *work);
274 static DECLARE_DELAYED_WORK(quota_release_work, quota_release_workfn);
276 static inline unsigned int
277 hashfn(const struct super_block *sb, struct kqid qid)
279 unsigned int id = from_kqid(&init_user_ns, qid);
283 tmp = (((unsigned long)sb>>L1_CACHE_SHIFT) ^ id) * (MAXQUOTAS - type);
284 return (tmp + (tmp >> dq_hash_bits)) & dq_hash_mask;
288 * Following list functions expect dq_list_lock to be held
290 static inline void insert_dquot_hash(struct dquot *dquot)
292 struct hlist_head *head;
293 head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id);
294 hlist_add_head(&dquot->dq_hash, head);
297 static inline void remove_dquot_hash(struct dquot *dquot)
299 hlist_del_init(&dquot->dq_hash);
302 static struct dquot *find_dquot(unsigned int hashent, struct super_block *sb,
307 hlist_for_each_entry(dquot, dquot_hash+hashent, dq_hash)
308 if (dquot->dq_sb == sb && qid_eq(dquot->dq_id, qid))
314 /* Add a dquot to the tail of the free list */
315 static inline void put_dquot_last(struct dquot *dquot)
317 list_add_tail(&dquot->dq_free, &free_dquots);
318 dqstats_inc(DQST_FREE_DQUOTS);
321 static inline void put_releasing_dquots(struct dquot *dquot)
323 list_add_tail(&dquot->dq_free, &releasing_dquots);
326 static inline void remove_free_dquot(struct dquot *dquot)
328 if (list_empty(&dquot->dq_free))
330 list_del_init(&dquot->dq_free);
331 if (!atomic_read(&dquot->dq_count))
332 dqstats_dec(DQST_FREE_DQUOTS);
335 static inline void put_inuse(struct dquot *dquot)
337 /* We add to the back of inuse list so we don't have to restart
338 * when traversing this list and we block */
339 list_add_tail(&dquot->dq_inuse, &inuse_list);
340 dqstats_inc(DQST_ALLOC_DQUOTS);
343 static inline void remove_inuse(struct dquot *dquot)
345 dqstats_dec(DQST_ALLOC_DQUOTS);
346 list_del(&dquot->dq_inuse);
349 * End of list functions needing dq_list_lock
352 static void wait_on_dquot(struct dquot *dquot)
354 mutex_lock(&dquot->dq_lock);
355 mutex_unlock(&dquot->dq_lock);
358 static inline int dquot_active(struct dquot *dquot)
360 return test_bit(DQ_ACTIVE_B, &dquot->dq_flags);
363 static inline int dquot_dirty(struct dquot *dquot)
365 return test_bit(DQ_MOD_B, &dquot->dq_flags);
368 static inline int mark_dquot_dirty(struct dquot *dquot)
370 return dquot->dq_sb->dq_op->mark_dirty(dquot);
373 /* Mark dquot dirty in atomic manner, and return it's old dirty flag state */
374 int dquot_mark_dquot_dirty(struct dquot *dquot)
378 if (!dquot_active(dquot))
381 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NOLIST_DIRTY)
382 return test_and_set_bit(DQ_MOD_B, &dquot->dq_flags);
384 /* If quota is dirty already, we don't have to acquire dq_list_lock */
385 if (dquot_dirty(dquot))
388 spin_lock(&dq_list_lock);
389 if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags)) {
390 list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)->
391 info[dquot->dq_id.type].dqi_dirty_list);
394 spin_unlock(&dq_list_lock);
397 EXPORT_SYMBOL(dquot_mark_dquot_dirty);
399 /* Dirtify all the dquots - this can block when journalling */
400 static inline int mark_all_dquot_dirty(struct dquot * const *dquot)
405 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
407 /* Even in case of error we have to continue */
408 ret = mark_dquot_dirty(dquot[cnt]);
415 static inline void dqput_all(struct dquot **dquot)
419 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
423 static inline int clear_dquot_dirty(struct dquot *dquot)
425 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NOLIST_DIRTY)
426 return test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags);
428 spin_lock(&dq_list_lock);
429 if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags)) {
430 spin_unlock(&dq_list_lock);
433 list_del_init(&dquot->dq_dirty);
434 spin_unlock(&dq_list_lock);
438 void mark_info_dirty(struct super_block *sb, int type)
440 spin_lock(&dq_data_lock);
441 sb_dqopt(sb)->info[type].dqi_flags |= DQF_INFO_DIRTY;
442 spin_unlock(&dq_data_lock);
444 EXPORT_SYMBOL(mark_info_dirty);
447 * Read dquot from disk and alloc space for it
450 int dquot_acquire(struct dquot *dquot)
452 int ret = 0, ret2 = 0;
453 unsigned int memalloc;
454 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
456 mutex_lock(&dquot->dq_lock);
457 memalloc = memalloc_nofs_save();
458 if (!test_bit(DQ_READ_B, &dquot->dq_flags)) {
459 ret = dqopt->ops[dquot->dq_id.type]->read_dqblk(dquot);
463 /* Make sure flags update is visible after dquot has been filled */
464 smp_mb__before_atomic();
465 set_bit(DQ_READ_B, &dquot->dq_flags);
466 /* Instantiate dquot if needed */
467 if (!dquot_active(dquot) && !dquot->dq_off) {
468 ret = dqopt->ops[dquot->dq_id.type]->commit_dqblk(dquot);
469 /* Write the info if needed */
470 if (info_dirty(&dqopt->info[dquot->dq_id.type])) {
471 ret2 = dqopt->ops[dquot->dq_id.type]->write_file_info(
472 dquot->dq_sb, dquot->dq_id.type);
482 * Make sure flags update is visible after on-disk struct has been
483 * allocated. Paired with smp_rmb() in dqget().
485 smp_mb__before_atomic();
486 set_bit(DQ_ACTIVE_B, &dquot->dq_flags);
488 memalloc_nofs_restore(memalloc);
489 mutex_unlock(&dquot->dq_lock);
492 EXPORT_SYMBOL(dquot_acquire);
495 * Write dquot to disk
497 int dquot_commit(struct dquot *dquot)
500 unsigned int memalloc;
501 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
503 mutex_lock(&dquot->dq_lock);
504 memalloc = memalloc_nofs_save();
505 if (!clear_dquot_dirty(dquot))
507 /* Inactive dquot can be only if there was error during read/init
508 * => we have better not writing it */
509 if (dquot_active(dquot))
510 ret = dqopt->ops[dquot->dq_id.type]->commit_dqblk(dquot);
514 memalloc_nofs_restore(memalloc);
515 mutex_unlock(&dquot->dq_lock);
518 EXPORT_SYMBOL(dquot_commit);
523 int dquot_release(struct dquot *dquot)
525 int ret = 0, ret2 = 0;
526 unsigned int memalloc;
527 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
529 mutex_lock(&dquot->dq_lock);
530 memalloc = memalloc_nofs_save();
531 /* Check whether we are not racing with some other dqget() */
532 if (dquot_is_busy(dquot))
534 if (dqopt->ops[dquot->dq_id.type]->release_dqblk) {
535 ret = dqopt->ops[dquot->dq_id.type]->release_dqblk(dquot);
537 if (info_dirty(&dqopt->info[dquot->dq_id.type])) {
538 ret2 = dqopt->ops[dquot->dq_id.type]->write_file_info(
539 dquot->dq_sb, dquot->dq_id.type);
544 clear_bit(DQ_ACTIVE_B, &dquot->dq_flags);
546 memalloc_nofs_restore(memalloc);
547 mutex_unlock(&dquot->dq_lock);
550 EXPORT_SYMBOL(dquot_release);
552 void dquot_destroy(struct dquot *dquot)
554 kmem_cache_free(dquot_cachep, dquot);
556 EXPORT_SYMBOL(dquot_destroy);
558 static inline void do_destroy_dquot(struct dquot *dquot)
560 dquot->dq_sb->dq_op->destroy_dquot(dquot);
563 /* Invalidate all dquots on the list. Note that this function is called after
564 * quota is disabled and pointers from inodes removed so there cannot be new
565 * quota users. There can still be some users of quotas due to inodes being
566 * just deleted or pruned by prune_icache() (those are not attached to any
567 * list) or parallel quotactl call. We have to wait for such users.
569 static void invalidate_dquots(struct super_block *sb, int type)
571 struct dquot *dquot, *tmp;
574 flush_delayed_work("a_release_work);
576 spin_lock(&dq_list_lock);
577 list_for_each_entry_safe(dquot, tmp, &inuse_list, dq_inuse) {
578 if (dquot->dq_sb != sb)
580 if (dquot->dq_id.type != type)
582 /* Wait for dquot users */
583 if (atomic_read(&dquot->dq_count)) {
584 /* dquot in releasing_dquots, flush and retry */
585 if (!list_empty(&dquot->dq_free)) {
586 spin_unlock(&dq_list_lock);
590 atomic_inc(&dquot->dq_count);
591 spin_unlock(&dq_list_lock);
593 * Once dqput() wakes us up, we know it's time to free
595 * IMPORTANT: we rely on the fact that there is always
596 * at most one process waiting for dquot to free.
597 * Otherwise dq_count would be > 1 and we would never
600 wait_event(dquot_ref_wq,
601 atomic_read(&dquot->dq_count) == 1);
603 /* At this moment dquot() need not exist (it could be
604 * reclaimed by prune_dqcache(). Hence we must
609 * Quota now has no users and it has been written on last
612 remove_dquot_hash(dquot);
613 remove_free_dquot(dquot);
615 do_destroy_dquot(dquot);
617 spin_unlock(&dq_list_lock);
620 /* Call callback for every active dquot on given filesystem */
621 int dquot_scan_active(struct super_block *sb,
622 int (*fn)(struct dquot *dquot, unsigned long priv),
625 struct dquot *dquot, *old_dquot = NULL;
628 WARN_ON_ONCE(!rwsem_is_locked(&sb->s_umount));
630 spin_lock(&dq_list_lock);
631 list_for_each_entry(dquot, &inuse_list, dq_inuse) {
632 if (!dquot_active(dquot))
634 if (dquot->dq_sb != sb)
636 /* Now we have active dquot so we can just increase use count */
637 atomic_inc(&dquot->dq_count);
638 spin_unlock(&dq_list_lock);
642 * ->release_dquot() can be racing with us. Our reference
643 * protects us from new calls to it so just wait for any
644 * outstanding call and recheck the DQ_ACTIVE_B after that.
646 wait_on_dquot(dquot);
647 if (dquot_active(dquot)) {
648 ret = fn(dquot, priv);
652 spin_lock(&dq_list_lock);
653 /* We are safe to continue now because our dquot could not
654 * be moved out of the inuse list while we hold the reference */
656 spin_unlock(&dq_list_lock);
661 EXPORT_SYMBOL(dquot_scan_active);
663 static inline int dquot_write_dquot(struct dquot *dquot)
665 int ret = dquot->dq_sb->dq_op->write_dquot(dquot);
667 quota_error(dquot->dq_sb, "Can't write quota structure "
668 "(error %d). Quota may get out of sync!", ret);
669 /* Clear dirty bit anyway to avoid infinite loop. */
670 clear_dquot_dirty(dquot);
675 /* Write all dquot structures to quota files */
676 int dquot_writeback_dquots(struct super_block *sb, int type)
678 struct list_head dirty;
680 struct quota_info *dqopt = sb_dqopt(sb);
684 WARN_ON_ONCE(!rwsem_is_locked(&sb->s_umount));
686 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
687 if (type != -1 && cnt != type)
689 if (!sb_has_quota_active(sb, cnt))
691 spin_lock(&dq_list_lock);
692 /* Move list away to avoid livelock. */
693 list_replace_init(&dqopt->info[cnt].dqi_dirty_list, &dirty);
694 while (!list_empty(&dirty)) {
695 dquot = list_first_entry(&dirty, struct dquot,
698 WARN_ON(!dquot_active(dquot));
700 /* Now we have active dquot from which someone is
701 * holding reference so we can safely just increase
704 spin_unlock(&dq_list_lock);
705 err = dquot_write_dquot(dquot);
709 spin_lock(&dq_list_lock);
711 spin_unlock(&dq_list_lock);
714 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
715 if ((cnt == type || type == -1) && sb_has_quota_active(sb, cnt)
716 && info_dirty(&dqopt->info[cnt]))
717 sb->dq_op->write_info(sb, cnt);
718 dqstats_inc(DQST_SYNCS);
722 EXPORT_SYMBOL(dquot_writeback_dquots);
724 /* Write all dquot structures to disk and make them visible from userspace */
725 int dquot_quota_sync(struct super_block *sb, int type)
727 struct quota_info *dqopt = sb_dqopt(sb);
731 ret = dquot_writeback_dquots(sb, type);
734 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE)
737 /* This is not very clever (and fast) but currently I don't know about
738 * any other simple way of getting quota data to disk and we must get
739 * them there for userspace to be visible... */
740 if (sb->s_op->sync_fs) {
741 ret = sb->s_op->sync_fs(sb, 1);
745 ret = sync_blockdev(sb->s_bdev);
750 * Now when everything is written we can discard the pagecache so
751 * that userspace sees the changes.
753 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
754 if (type != -1 && cnt != type)
756 if (!sb_has_quota_active(sb, cnt))
758 inode_lock(dqopt->files[cnt]);
759 truncate_inode_pages(&dqopt->files[cnt]->i_data, 0);
760 inode_unlock(dqopt->files[cnt]);
765 EXPORT_SYMBOL(dquot_quota_sync);
768 dqcache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
771 unsigned long freed = 0;
773 spin_lock(&dq_list_lock);
774 while (!list_empty(&free_dquots) && sc->nr_to_scan) {
775 dquot = list_first_entry(&free_dquots, struct dquot, dq_free);
776 remove_dquot_hash(dquot);
777 remove_free_dquot(dquot);
779 do_destroy_dquot(dquot);
783 spin_unlock(&dq_list_lock);
788 dqcache_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
790 return vfs_pressure_ratio(
791 percpu_counter_read_positive(&dqstats.counter[DQST_FREE_DQUOTS]));
794 static struct shrinker dqcache_shrinker = {
795 .count_objects = dqcache_shrink_count,
796 .scan_objects = dqcache_shrink_scan,
797 .seeks = DEFAULT_SEEKS,
801 * Safely release dquot and put reference to dquot.
803 static void quota_release_workfn(struct work_struct *work)
806 struct list_head rls_head;
808 spin_lock(&dq_list_lock);
809 /* Exchange the list head to avoid livelock. */
810 list_replace_init(&releasing_dquots, &rls_head);
811 spin_unlock(&dq_list_lock);
814 synchronize_srcu(&dquot_srcu);
815 spin_lock(&dq_list_lock);
816 while (!list_empty(&rls_head)) {
817 dquot = list_first_entry(&rls_head, struct dquot, dq_free);
818 /* Dquot got used again? */
819 if (atomic_read(&dquot->dq_count) > 1) {
820 remove_free_dquot(dquot);
821 atomic_dec(&dquot->dq_count);
824 if (dquot_dirty(dquot)) {
825 spin_unlock(&dq_list_lock);
826 /* Commit dquot before releasing */
827 dquot_write_dquot(dquot);
830 if (dquot_active(dquot)) {
831 spin_unlock(&dq_list_lock);
832 dquot->dq_sb->dq_op->release_dquot(dquot);
835 /* Dquot is inactive and clean, now move it to free list */
836 remove_free_dquot(dquot);
837 atomic_dec(&dquot->dq_count);
838 put_dquot_last(dquot);
840 spin_unlock(&dq_list_lock);
844 * Put reference to dquot
846 void dqput(struct dquot *dquot)
850 #ifdef CONFIG_QUOTA_DEBUG
851 if (!atomic_read(&dquot->dq_count)) {
852 quota_error(dquot->dq_sb, "trying to free free dquot of %s %d",
853 quotatypes[dquot->dq_id.type],
854 from_kqid(&init_user_ns, dquot->dq_id));
858 dqstats_inc(DQST_DROPS);
860 spin_lock(&dq_list_lock);
861 if (atomic_read(&dquot->dq_count) > 1) {
862 /* We have more than one user... nothing to do */
863 atomic_dec(&dquot->dq_count);
864 /* Releasing dquot during quotaoff phase? */
865 if (!sb_has_quota_active(dquot->dq_sb, dquot->dq_id.type) &&
866 atomic_read(&dquot->dq_count) == 1)
867 wake_up(&dquot_ref_wq);
868 spin_unlock(&dq_list_lock);
872 /* Need to release dquot? */
873 #ifdef CONFIG_QUOTA_DEBUG
875 BUG_ON(!list_empty(&dquot->dq_free));
877 put_releasing_dquots(dquot);
878 spin_unlock(&dq_list_lock);
879 queue_delayed_work(system_unbound_wq, "a_release_work, 1);
881 EXPORT_SYMBOL(dqput);
883 struct dquot *dquot_alloc(struct super_block *sb, int type)
885 return kmem_cache_zalloc(dquot_cachep, GFP_NOFS);
887 EXPORT_SYMBOL(dquot_alloc);
889 static struct dquot *get_empty_dquot(struct super_block *sb, int type)
893 dquot = sb->dq_op->alloc_dquot(sb, type);
897 mutex_init(&dquot->dq_lock);
898 INIT_LIST_HEAD(&dquot->dq_free);
899 INIT_LIST_HEAD(&dquot->dq_inuse);
900 INIT_HLIST_NODE(&dquot->dq_hash);
901 INIT_LIST_HEAD(&dquot->dq_dirty);
903 dquot->dq_id = make_kqid_invalid(type);
904 atomic_set(&dquot->dq_count, 1);
905 spin_lock_init(&dquot->dq_dqb_lock);
911 * Get reference to dquot
913 * Locking is slightly tricky here. We are guarded from parallel quotaoff()
914 * destroying our dquot by:
915 * a) checking for quota flags under dq_list_lock and
916 * b) getting a reference to dquot before we release dq_list_lock
918 struct dquot *dqget(struct super_block *sb, struct kqid qid)
920 unsigned int hashent = hashfn(sb, qid);
921 struct dquot *dquot, *empty = NULL;
923 if (!qid_has_mapping(sb->s_user_ns, qid))
924 return ERR_PTR(-EINVAL);
926 if (!sb_has_quota_active(sb, qid.type))
927 return ERR_PTR(-ESRCH);
929 spin_lock(&dq_list_lock);
930 spin_lock(&dq_state_lock);
931 if (!sb_has_quota_active(sb, qid.type)) {
932 spin_unlock(&dq_state_lock);
933 spin_unlock(&dq_list_lock);
934 dquot = ERR_PTR(-ESRCH);
937 spin_unlock(&dq_state_lock);
939 dquot = find_dquot(hashent, sb, qid);
942 spin_unlock(&dq_list_lock);
943 empty = get_empty_dquot(sb, qid.type);
945 schedule(); /* Try to wait for a moment... */
951 /* all dquots go on the inuse_list */
953 /* hash it first so it can be found */
954 insert_dquot_hash(dquot);
955 spin_unlock(&dq_list_lock);
956 dqstats_inc(DQST_LOOKUPS);
958 if (!atomic_read(&dquot->dq_count))
959 remove_free_dquot(dquot);
960 atomic_inc(&dquot->dq_count);
961 spin_unlock(&dq_list_lock);
962 dqstats_inc(DQST_CACHE_HITS);
963 dqstats_inc(DQST_LOOKUPS);
965 /* Wait for dq_lock - after this we know that either dquot_release() is
966 * already finished or it will be canceled due to dq_count > 1 test */
967 wait_on_dquot(dquot);
968 /* Read the dquot / allocate space in quota file */
969 if (!dquot_active(dquot)) {
972 err = sb->dq_op->acquire_dquot(dquot);
975 dquot = ERR_PTR(err);
980 * Make sure following reads see filled structure - paired with
981 * smp_mb__before_atomic() in dquot_acquire().
984 #ifdef CONFIG_QUOTA_DEBUG
985 BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */
989 do_destroy_dquot(empty);
993 EXPORT_SYMBOL(dqget);
995 static inline struct dquot **i_dquot(struct inode *inode)
997 return inode->i_sb->s_op->get_dquots(inode);
1000 static int dqinit_needed(struct inode *inode, int type)
1002 struct dquot * const *dquots;
1005 if (IS_NOQUOTA(inode))
1008 dquots = i_dquot(inode);
1010 return !dquots[type];
1011 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1017 /* This routine is guarded by s_umount semaphore */
1018 static int add_dquot_ref(struct super_block *sb, int type)
1020 struct inode *inode, *old_inode = NULL;
1021 #ifdef CONFIG_QUOTA_DEBUG
1026 spin_lock(&sb->s_inode_list_lock);
1027 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
1028 spin_lock(&inode->i_lock);
1029 if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) ||
1030 !atomic_read(&inode->i_writecount) ||
1031 !dqinit_needed(inode, type)) {
1032 spin_unlock(&inode->i_lock);
1036 spin_unlock(&inode->i_lock);
1037 spin_unlock(&sb->s_inode_list_lock);
1039 #ifdef CONFIG_QUOTA_DEBUG
1040 if (unlikely(inode_get_rsv_space(inode) > 0))
1044 err = __dquot_initialize(inode, type);
1051 * We hold a reference to 'inode' so it couldn't have been
1052 * removed from s_inodes list while we dropped the
1053 * s_inode_list_lock. We cannot iput the inode now as we can be
1054 * holding the last reference and we cannot iput it under
1055 * s_inode_list_lock. So we keep the reference and iput it
1060 spin_lock(&sb->s_inode_list_lock);
1062 spin_unlock(&sb->s_inode_list_lock);
1065 #ifdef CONFIG_QUOTA_DEBUG
1067 quota_error(sb, "Writes happened before quota was turned on "
1068 "thus quota information is probably inconsistent. "
1069 "Please run quotacheck(8)");
1075 static void remove_dquot_ref(struct super_block *sb, int type)
1077 struct inode *inode;
1078 #ifdef CONFIG_QUOTA_DEBUG
1082 spin_lock(&sb->s_inode_list_lock);
1083 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
1085 * We have to scan also I_NEW inodes because they can already
1086 * have quota pointer initialized. Luckily, we need to touch
1087 * only quota pointers and these have separate locking
1090 spin_lock(&dq_data_lock);
1091 if (!IS_NOQUOTA(inode)) {
1092 struct dquot **dquots = i_dquot(inode);
1093 struct dquot *dquot = dquots[type];
1095 #ifdef CONFIG_QUOTA_DEBUG
1096 if (unlikely(inode_get_rsv_space(inode) > 0))
1099 dquots[type] = NULL;
1103 spin_unlock(&dq_data_lock);
1105 spin_unlock(&sb->s_inode_list_lock);
1106 #ifdef CONFIG_QUOTA_DEBUG
1108 printk(KERN_WARNING "VFS (%s): Writes happened after quota"
1109 " was disabled thus quota information is probably "
1110 "inconsistent. Please run quotacheck(8).\n", sb->s_id);
1115 /* Gather all references from inodes and drop them */
1116 static void drop_dquot_ref(struct super_block *sb, int type)
1119 remove_dquot_ref(sb, type);
1123 void dquot_free_reserved_space(struct dquot *dquot, qsize_t number)
1125 if (dquot->dq_dqb.dqb_rsvspace >= number)
1126 dquot->dq_dqb.dqb_rsvspace -= number;
1129 dquot->dq_dqb.dqb_rsvspace = 0;
1131 if (dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace <=
1132 dquot->dq_dqb.dqb_bsoftlimit)
1133 dquot->dq_dqb.dqb_btime = (time64_t) 0;
1134 clear_bit(DQ_BLKS_B, &dquot->dq_flags);
1137 static void dquot_decr_inodes(struct dquot *dquot, qsize_t number)
1139 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE ||
1140 dquot->dq_dqb.dqb_curinodes >= number)
1141 dquot->dq_dqb.dqb_curinodes -= number;
1143 dquot->dq_dqb.dqb_curinodes = 0;
1144 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit)
1145 dquot->dq_dqb.dqb_itime = (time64_t) 0;
1146 clear_bit(DQ_INODES_B, &dquot->dq_flags);
1149 static void dquot_decr_space(struct dquot *dquot, qsize_t number)
1151 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE ||
1152 dquot->dq_dqb.dqb_curspace >= number)
1153 dquot->dq_dqb.dqb_curspace -= number;
1155 dquot->dq_dqb.dqb_curspace = 0;
1156 if (dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace <=
1157 dquot->dq_dqb.dqb_bsoftlimit)
1158 dquot->dq_dqb.dqb_btime = (time64_t) 0;
1159 clear_bit(DQ_BLKS_B, &dquot->dq_flags);
1163 struct super_block *w_sb;
1164 struct kqid w_dq_id;
1168 static int warning_issued(struct dquot *dquot, const int warntype)
1170 int flag = (warntype == QUOTA_NL_BHARDWARN ||
1171 warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B :
1172 ((warntype == QUOTA_NL_IHARDWARN ||
1173 warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0);
1177 return test_and_set_bit(flag, &dquot->dq_flags);
1180 #ifdef CONFIG_PRINT_QUOTA_WARNING
1181 static int flag_print_warnings = 1;
1183 static int need_print_warning(struct dquot_warn *warn)
1185 if (!flag_print_warnings)
1188 switch (warn->w_dq_id.type) {
1190 return uid_eq(current_fsuid(), warn->w_dq_id.uid);
1192 return in_group_p(warn->w_dq_id.gid);
1199 /* Print warning to user which exceeded quota */
1200 static void print_warning(struct dquot_warn *warn)
1203 struct tty_struct *tty;
1204 int warntype = warn->w_type;
1206 if (warntype == QUOTA_NL_IHARDBELOW ||
1207 warntype == QUOTA_NL_ISOFTBELOW ||
1208 warntype == QUOTA_NL_BHARDBELOW ||
1209 warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(warn))
1212 tty = get_current_tty();
1215 tty_write_message(tty, warn->w_sb->s_id);
1216 if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN)
1217 tty_write_message(tty, ": warning, ");
1219 tty_write_message(tty, ": write failed, ");
1220 tty_write_message(tty, quotatypes[warn->w_dq_id.type]);
1222 case QUOTA_NL_IHARDWARN:
1223 msg = " file limit reached.\r\n";
1225 case QUOTA_NL_ISOFTLONGWARN:
1226 msg = " file quota exceeded too long.\r\n";
1228 case QUOTA_NL_ISOFTWARN:
1229 msg = " file quota exceeded.\r\n";
1231 case QUOTA_NL_BHARDWARN:
1232 msg = " block limit reached.\r\n";
1234 case QUOTA_NL_BSOFTLONGWARN:
1235 msg = " block quota exceeded too long.\r\n";
1237 case QUOTA_NL_BSOFTWARN:
1238 msg = " block quota exceeded.\r\n";
1241 tty_write_message(tty, msg);
1246 static void prepare_warning(struct dquot_warn *warn, struct dquot *dquot,
1249 if (warning_issued(dquot, warntype))
1251 warn->w_type = warntype;
1252 warn->w_sb = dquot->dq_sb;
1253 warn->w_dq_id = dquot->dq_id;
1257 * Write warnings to the console and send warning messages over netlink.
1259 * Note that this function can call into tty and networking code.
1261 static void flush_warnings(struct dquot_warn *warn)
1265 for (i = 0; i < MAXQUOTAS; i++) {
1266 if (warn[i].w_type == QUOTA_NL_NOWARN)
1268 #ifdef CONFIG_PRINT_QUOTA_WARNING
1269 print_warning(&warn[i]);
1271 quota_send_warning(warn[i].w_dq_id,
1272 warn[i].w_sb->s_dev, warn[i].w_type);
1276 static int ignore_hardlimit(struct dquot *dquot)
1278 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type];
1280 return capable(CAP_SYS_RESOURCE) &&
1281 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD ||
1282 !(info->dqi_flags & DQF_ROOT_SQUASH));
1285 static int dquot_add_inodes(struct dquot *dquot, qsize_t inodes,
1286 struct dquot_warn *warn)
1291 spin_lock(&dquot->dq_dqb_lock);
1292 newinodes = dquot->dq_dqb.dqb_curinodes + inodes;
1293 if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_id.type) ||
1294 test_bit(DQ_FAKE_B, &dquot->dq_flags))
1297 if (dquot->dq_dqb.dqb_ihardlimit &&
1298 newinodes > dquot->dq_dqb.dqb_ihardlimit &&
1299 !ignore_hardlimit(dquot)) {
1300 prepare_warning(warn, dquot, QUOTA_NL_IHARDWARN);
1305 if (dquot->dq_dqb.dqb_isoftlimit &&
1306 newinodes > dquot->dq_dqb.dqb_isoftlimit &&
1307 dquot->dq_dqb.dqb_itime &&
1308 ktime_get_real_seconds() >= dquot->dq_dqb.dqb_itime &&
1309 !ignore_hardlimit(dquot)) {
1310 prepare_warning(warn, dquot, QUOTA_NL_ISOFTLONGWARN);
1315 if (dquot->dq_dqb.dqb_isoftlimit &&
1316 newinodes > dquot->dq_dqb.dqb_isoftlimit &&
1317 dquot->dq_dqb.dqb_itime == 0) {
1318 prepare_warning(warn, dquot, QUOTA_NL_ISOFTWARN);
1319 dquot->dq_dqb.dqb_itime = ktime_get_real_seconds() +
1320 sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type].dqi_igrace;
1323 dquot->dq_dqb.dqb_curinodes = newinodes;
1326 spin_unlock(&dquot->dq_dqb_lock);
1330 static int dquot_add_space(struct dquot *dquot, qsize_t space,
1331 qsize_t rsv_space, unsigned int flags,
1332 struct dquot_warn *warn)
1335 struct super_block *sb = dquot->dq_sb;
1338 spin_lock(&dquot->dq_dqb_lock);
1339 if (!sb_has_quota_limits_enabled(sb, dquot->dq_id.type) ||
1340 test_bit(DQ_FAKE_B, &dquot->dq_flags))
1343 tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace
1344 + space + rsv_space;
1346 if (dquot->dq_dqb.dqb_bhardlimit &&
1347 tspace > dquot->dq_dqb.dqb_bhardlimit &&
1348 !ignore_hardlimit(dquot)) {
1349 if (flags & DQUOT_SPACE_WARN)
1350 prepare_warning(warn, dquot, QUOTA_NL_BHARDWARN);
1355 if (dquot->dq_dqb.dqb_bsoftlimit &&
1356 tspace > dquot->dq_dqb.dqb_bsoftlimit &&
1357 dquot->dq_dqb.dqb_btime &&
1358 ktime_get_real_seconds() >= dquot->dq_dqb.dqb_btime &&
1359 !ignore_hardlimit(dquot)) {
1360 if (flags & DQUOT_SPACE_WARN)
1361 prepare_warning(warn, dquot, QUOTA_NL_BSOFTLONGWARN);
1366 if (dquot->dq_dqb.dqb_bsoftlimit &&
1367 tspace > dquot->dq_dqb.dqb_bsoftlimit &&
1368 dquot->dq_dqb.dqb_btime == 0) {
1369 if (flags & DQUOT_SPACE_WARN) {
1370 prepare_warning(warn, dquot, QUOTA_NL_BSOFTWARN);
1371 dquot->dq_dqb.dqb_btime = ktime_get_real_seconds() +
1372 sb_dqopt(sb)->info[dquot->dq_id.type].dqi_bgrace;
1375 * We don't allow preallocation to exceed softlimit so exceeding will
1384 * We have to be careful and go through warning generation & grace time
1385 * setting even if DQUOT_SPACE_NOFAIL is set. That's why we check it
1388 if (flags & DQUOT_SPACE_NOFAIL)
1391 dquot->dq_dqb.dqb_rsvspace += rsv_space;
1392 dquot->dq_dqb.dqb_curspace += space;
1394 spin_unlock(&dquot->dq_dqb_lock);
1398 static int info_idq_free(struct dquot *dquot, qsize_t inodes)
1402 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) ||
1403 dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit ||
1404 !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_id.type))
1405 return QUOTA_NL_NOWARN;
1407 newinodes = dquot->dq_dqb.dqb_curinodes - inodes;
1408 if (newinodes <= dquot->dq_dqb.dqb_isoftlimit)
1409 return QUOTA_NL_ISOFTBELOW;
1410 if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit &&
1411 newinodes < dquot->dq_dqb.dqb_ihardlimit)
1412 return QUOTA_NL_IHARDBELOW;
1413 return QUOTA_NL_NOWARN;
1416 static int info_bdq_free(struct dquot *dquot, qsize_t space)
1420 tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace;
1422 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) ||
1423 tspace <= dquot->dq_dqb.dqb_bsoftlimit)
1424 return QUOTA_NL_NOWARN;
1426 if (tspace - space <= dquot->dq_dqb.dqb_bsoftlimit)
1427 return QUOTA_NL_BSOFTBELOW;
1428 if (tspace >= dquot->dq_dqb.dqb_bhardlimit &&
1429 tspace - space < dquot->dq_dqb.dqb_bhardlimit)
1430 return QUOTA_NL_BHARDBELOW;
1431 return QUOTA_NL_NOWARN;
1434 static int inode_quota_active(const struct inode *inode)
1436 struct super_block *sb = inode->i_sb;
1438 if (IS_NOQUOTA(inode))
1440 return sb_any_quota_loaded(sb) & ~sb_any_quota_suspended(sb);
1444 * Initialize quota pointers in inode
1446 * It is better to call this function outside of any transaction as it
1447 * might need a lot of space in journal for dquot structure allocation.
1449 static int __dquot_initialize(struct inode *inode, int type)
1451 int cnt, init_needed = 0;
1452 struct dquot **dquots, *got[MAXQUOTAS] = {};
1453 struct super_block *sb = inode->i_sb;
1457 if (!inode_quota_active(inode))
1460 dquots = i_dquot(inode);
1462 /* First get references to structures we might need. */
1463 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1467 struct dquot *dquot;
1469 if (type != -1 && cnt != type)
1472 * The i_dquot should have been initialized in most cases,
1473 * we check it without locking here to avoid unnecessary
1474 * dqget()/dqput() calls.
1479 if (!sb_has_quota_active(sb, cnt))
1486 qid = make_kqid_uid(inode->i_uid);
1489 qid = make_kqid_gid(inode->i_gid);
1492 rc = inode->i_sb->dq_op->get_projid(inode, &projid);
1495 qid = make_kqid_projid(projid);
1498 dquot = dqget(sb, qid);
1499 if (IS_ERR(dquot)) {
1500 /* We raced with somebody turning quotas off... */
1501 if (PTR_ERR(dquot) != -ESRCH) {
1502 ret = PTR_ERR(dquot);
1510 /* All required i_dquot has been initialized */
1514 spin_lock(&dq_data_lock);
1515 if (IS_NOQUOTA(inode))
1517 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1518 if (type != -1 && cnt != type)
1520 /* Avoid races with quotaoff() */
1521 if (!sb_has_quota_active(sb, cnt))
1523 /* We could race with quotaon or dqget() could have failed */
1527 dquots[cnt] = got[cnt];
1530 * Make quota reservation system happy if someone
1531 * did a write before quota was turned on
1533 rsv = inode_get_rsv_space(inode);
1534 if (unlikely(rsv)) {
1535 spin_lock(&inode->i_lock);
1536 /* Get reservation again under proper lock */
1537 rsv = __inode_get_rsv_space(inode);
1538 spin_lock(&dquots[cnt]->dq_dqb_lock);
1539 dquots[cnt]->dq_dqb.dqb_rsvspace += rsv;
1540 spin_unlock(&dquots[cnt]->dq_dqb_lock);
1541 spin_unlock(&inode->i_lock);
1546 spin_unlock(&dq_data_lock);
1548 /* Drop unused references */
1554 int dquot_initialize(struct inode *inode)
1556 return __dquot_initialize(inode, -1);
1558 EXPORT_SYMBOL(dquot_initialize);
1560 bool dquot_initialize_needed(struct inode *inode)
1562 struct dquot **dquots;
1565 if (!inode_quota_active(inode))
1568 dquots = i_dquot(inode);
1569 for (i = 0; i < MAXQUOTAS; i++)
1570 if (!dquots[i] && sb_has_quota_active(inode->i_sb, i))
1574 EXPORT_SYMBOL(dquot_initialize_needed);
1577 * Release all quotas referenced by inode.
1579 * This function only be called on inode free or converting
1580 * a file to quota file, no other users for the i_dquot in
1581 * both cases, so we needn't call synchronize_srcu() after
1584 static void __dquot_drop(struct inode *inode)
1587 struct dquot **dquots = i_dquot(inode);
1588 struct dquot *put[MAXQUOTAS];
1590 spin_lock(&dq_data_lock);
1591 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1592 put[cnt] = dquots[cnt];
1595 spin_unlock(&dq_data_lock);
1599 void dquot_drop(struct inode *inode)
1601 struct dquot * const *dquots;
1604 if (IS_NOQUOTA(inode))
1608 * Test before calling to rule out calls from proc and such
1609 * where we are not allowed to block. Note that this is
1610 * actually reliable test even without the lock - the caller
1611 * must assure that nobody can come after the DQUOT_DROP and
1612 * add quota pointers back anyway.
1614 dquots = i_dquot(inode);
1615 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1620 if (cnt < MAXQUOTAS)
1621 __dquot_drop(inode);
1623 EXPORT_SYMBOL(dquot_drop);
1626 * inode_reserved_space is managed internally by quota, and protected by
1627 * i_lock similar to i_blocks+i_bytes.
1629 static qsize_t *inode_reserved_space(struct inode * inode)
1631 /* Filesystem must explicitly define it's own method in order to use
1632 * quota reservation interface */
1633 BUG_ON(!inode->i_sb->dq_op->get_reserved_space);
1634 return inode->i_sb->dq_op->get_reserved_space(inode);
1637 static qsize_t __inode_get_rsv_space(struct inode *inode)
1639 if (!inode->i_sb->dq_op->get_reserved_space)
1641 return *inode_reserved_space(inode);
1644 static qsize_t inode_get_rsv_space(struct inode *inode)
1648 if (!inode->i_sb->dq_op->get_reserved_space)
1650 spin_lock(&inode->i_lock);
1651 ret = __inode_get_rsv_space(inode);
1652 spin_unlock(&inode->i_lock);
1657 * This functions updates i_blocks+i_bytes fields and quota information
1658 * (together with appropriate checks).
1660 * NOTE: We absolutely rely on the fact that caller dirties the inode
1661 * (usually helpers in quotaops.h care about this) and holds a handle for
1662 * the current transaction so that dquot write and inode write go into the
1667 * This operation can block, but only after everything is updated
1669 int __dquot_alloc_space(struct inode *inode, qsize_t number, int flags)
1671 int cnt, ret = 0, index;
1672 struct dquot_warn warn[MAXQUOTAS];
1673 int reserve = flags & DQUOT_SPACE_RESERVE;
1674 struct dquot **dquots;
1676 if (!inode_quota_active(inode)) {
1678 spin_lock(&inode->i_lock);
1679 *inode_reserved_space(inode) += number;
1680 spin_unlock(&inode->i_lock);
1682 inode_add_bytes(inode, number);
1687 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1688 warn[cnt].w_type = QUOTA_NL_NOWARN;
1690 dquots = i_dquot(inode);
1691 index = srcu_read_lock(&dquot_srcu);
1692 spin_lock(&inode->i_lock);
1693 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1697 ret = dquot_add_space(dquots[cnt], 0, number, flags,
1700 ret = dquot_add_space(dquots[cnt], number, 0, flags,
1704 /* Back out changes we already did */
1705 for (cnt--; cnt >= 0; cnt--) {
1708 spin_lock(&dquots[cnt]->dq_dqb_lock);
1710 dquot_free_reserved_space(dquots[cnt],
1713 dquot_decr_space(dquots[cnt], number);
1714 spin_unlock(&dquots[cnt]->dq_dqb_lock);
1716 spin_unlock(&inode->i_lock);
1717 goto out_flush_warn;
1721 *inode_reserved_space(inode) += number;
1723 __inode_add_bytes(inode, number);
1724 spin_unlock(&inode->i_lock);
1727 goto out_flush_warn;
1728 mark_all_dquot_dirty(dquots);
1730 srcu_read_unlock(&dquot_srcu, index);
1731 flush_warnings(warn);
1735 EXPORT_SYMBOL(__dquot_alloc_space);
1738 * This operation can block, but only after everything is updated
1740 int dquot_alloc_inode(struct inode *inode)
1742 int cnt, ret = 0, index;
1743 struct dquot_warn warn[MAXQUOTAS];
1744 struct dquot * const *dquots;
1746 if (!inode_quota_active(inode))
1748 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
1749 warn[cnt].w_type = QUOTA_NL_NOWARN;
1751 dquots = i_dquot(inode);
1752 index = srcu_read_lock(&dquot_srcu);
1753 spin_lock(&inode->i_lock);
1754 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1757 ret = dquot_add_inodes(dquots[cnt], 1, &warn[cnt]);
1759 for (cnt--; cnt >= 0; cnt--) {
1762 /* Back out changes we already did */
1763 spin_lock(&dquots[cnt]->dq_dqb_lock);
1764 dquot_decr_inodes(dquots[cnt], 1);
1765 spin_unlock(&dquots[cnt]->dq_dqb_lock);
1772 spin_unlock(&inode->i_lock);
1774 mark_all_dquot_dirty(dquots);
1775 srcu_read_unlock(&dquot_srcu, index);
1776 flush_warnings(warn);
1779 EXPORT_SYMBOL(dquot_alloc_inode);
1782 * Convert in-memory reserved quotas to real consumed quotas
1784 int dquot_claim_space_nodirty(struct inode *inode, qsize_t number)
1786 struct dquot **dquots;
1789 if (!inode_quota_active(inode)) {
1790 spin_lock(&inode->i_lock);
1791 *inode_reserved_space(inode) -= number;
1792 __inode_add_bytes(inode, number);
1793 spin_unlock(&inode->i_lock);
1797 dquots = i_dquot(inode);
1798 index = srcu_read_lock(&dquot_srcu);
1799 spin_lock(&inode->i_lock);
1800 /* Claim reserved quotas to allocated quotas */
1801 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1803 struct dquot *dquot = dquots[cnt];
1805 spin_lock(&dquot->dq_dqb_lock);
1806 if (WARN_ON_ONCE(dquot->dq_dqb.dqb_rsvspace < number))
1807 number = dquot->dq_dqb.dqb_rsvspace;
1808 dquot->dq_dqb.dqb_curspace += number;
1809 dquot->dq_dqb.dqb_rsvspace -= number;
1810 spin_unlock(&dquot->dq_dqb_lock);
1813 /* Update inode bytes */
1814 *inode_reserved_space(inode) -= number;
1815 __inode_add_bytes(inode, number);
1816 spin_unlock(&inode->i_lock);
1817 mark_all_dquot_dirty(dquots);
1818 srcu_read_unlock(&dquot_srcu, index);
1821 EXPORT_SYMBOL(dquot_claim_space_nodirty);
1824 * Convert allocated space back to in-memory reserved quotas
1826 void dquot_reclaim_space_nodirty(struct inode *inode, qsize_t number)
1828 struct dquot **dquots;
1831 if (!inode_quota_active(inode)) {
1832 spin_lock(&inode->i_lock);
1833 *inode_reserved_space(inode) += number;
1834 __inode_sub_bytes(inode, number);
1835 spin_unlock(&inode->i_lock);
1839 dquots = i_dquot(inode);
1840 index = srcu_read_lock(&dquot_srcu);
1841 spin_lock(&inode->i_lock);
1842 /* Claim reserved quotas to allocated quotas */
1843 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1845 struct dquot *dquot = dquots[cnt];
1847 spin_lock(&dquot->dq_dqb_lock);
1848 if (WARN_ON_ONCE(dquot->dq_dqb.dqb_curspace < number))
1849 number = dquot->dq_dqb.dqb_curspace;
1850 dquot->dq_dqb.dqb_rsvspace += number;
1851 dquot->dq_dqb.dqb_curspace -= number;
1852 spin_unlock(&dquot->dq_dqb_lock);
1855 /* Update inode bytes */
1856 *inode_reserved_space(inode) += number;
1857 __inode_sub_bytes(inode, number);
1858 spin_unlock(&inode->i_lock);
1859 mark_all_dquot_dirty(dquots);
1860 srcu_read_unlock(&dquot_srcu, index);
1863 EXPORT_SYMBOL(dquot_reclaim_space_nodirty);
1866 * This operation can block, but only after everything is updated
1868 void __dquot_free_space(struct inode *inode, qsize_t number, int flags)
1871 struct dquot_warn warn[MAXQUOTAS];
1872 struct dquot **dquots;
1873 int reserve = flags & DQUOT_SPACE_RESERVE, index;
1875 if (!inode_quota_active(inode)) {
1877 spin_lock(&inode->i_lock);
1878 *inode_reserved_space(inode) -= number;
1879 spin_unlock(&inode->i_lock);
1881 inode_sub_bytes(inode, number);
1886 dquots = i_dquot(inode);
1887 index = srcu_read_lock(&dquot_srcu);
1888 spin_lock(&inode->i_lock);
1889 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1892 warn[cnt].w_type = QUOTA_NL_NOWARN;
1895 spin_lock(&dquots[cnt]->dq_dqb_lock);
1896 wtype = info_bdq_free(dquots[cnt], number);
1897 if (wtype != QUOTA_NL_NOWARN)
1898 prepare_warning(&warn[cnt], dquots[cnt], wtype);
1900 dquot_free_reserved_space(dquots[cnt], number);
1902 dquot_decr_space(dquots[cnt], number);
1903 spin_unlock(&dquots[cnt]->dq_dqb_lock);
1906 *inode_reserved_space(inode) -= number;
1908 __inode_sub_bytes(inode, number);
1909 spin_unlock(&inode->i_lock);
1913 mark_all_dquot_dirty(dquots);
1915 srcu_read_unlock(&dquot_srcu, index);
1916 flush_warnings(warn);
1918 EXPORT_SYMBOL(__dquot_free_space);
1921 * This operation can block, but only after everything is updated
1923 void dquot_free_inode(struct inode *inode)
1926 struct dquot_warn warn[MAXQUOTAS];
1927 struct dquot * const *dquots;
1930 if (!inode_quota_active(inode))
1933 dquots = i_dquot(inode);
1934 index = srcu_read_lock(&dquot_srcu);
1935 spin_lock(&inode->i_lock);
1936 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1939 warn[cnt].w_type = QUOTA_NL_NOWARN;
1942 spin_lock(&dquots[cnt]->dq_dqb_lock);
1943 wtype = info_idq_free(dquots[cnt], 1);
1944 if (wtype != QUOTA_NL_NOWARN)
1945 prepare_warning(&warn[cnt], dquots[cnt], wtype);
1946 dquot_decr_inodes(dquots[cnt], 1);
1947 spin_unlock(&dquots[cnt]->dq_dqb_lock);
1949 spin_unlock(&inode->i_lock);
1950 mark_all_dquot_dirty(dquots);
1951 srcu_read_unlock(&dquot_srcu, index);
1952 flush_warnings(warn);
1954 EXPORT_SYMBOL(dquot_free_inode);
1957 * Transfer the number of inode and blocks from one diskquota to an other.
1958 * On success, dquot references in transfer_to are consumed and references
1959 * to original dquots that need to be released are placed there. On failure,
1960 * references are kept untouched.
1962 * This operation can block, but only after everything is updated
1963 * A transaction must be started when entering this function.
1965 * We are holding reference on transfer_from & transfer_to, no need to
1966 * protect them by srcu_read_lock().
1968 int __dquot_transfer(struct inode *inode, struct dquot **transfer_to)
1971 qsize_t rsv_space = 0;
1972 qsize_t inode_usage = 1;
1973 struct dquot *transfer_from[MAXQUOTAS] = {};
1975 char is_valid[MAXQUOTAS] = {};
1976 struct dquot_warn warn_to[MAXQUOTAS];
1977 struct dquot_warn warn_from_inodes[MAXQUOTAS];
1978 struct dquot_warn warn_from_space[MAXQUOTAS];
1980 if (IS_NOQUOTA(inode))
1983 if (inode->i_sb->dq_op->get_inode_usage) {
1984 ret = inode->i_sb->dq_op->get_inode_usage(inode, &inode_usage);
1989 /* Initialize the arrays */
1990 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1991 warn_to[cnt].w_type = QUOTA_NL_NOWARN;
1992 warn_from_inodes[cnt].w_type = QUOTA_NL_NOWARN;
1993 warn_from_space[cnt].w_type = QUOTA_NL_NOWARN;
1996 spin_lock(&dq_data_lock);
1997 spin_lock(&inode->i_lock);
1998 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */
1999 spin_unlock(&inode->i_lock);
2000 spin_unlock(&dq_data_lock);
2003 cur_space = __inode_get_bytes(inode);
2004 rsv_space = __inode_get_rsv_space(inode);
2006 * Build the transfer_from list, check limits, and update usage in
2007 * the target structures.
2009 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
2011 * Skip changes for same uid or gid or for turned off quota-type.
2013 if (!transfer_to[cnt])
2015 /* Avoid races with quotaoff() */
2016 if (!sb_has_quota_active(inode->i_sb, cnt))
2019 transfer_from[cnt] = i_dquot(inode)[cnt];
2020 ret = dquot_add_inodes(transfer_to[cnt], inode_usage,
2024 ret = dquot_add_space(transfer_to[cnt], cur_space, rsv_space,
2025 DQUOT_SPACE_WARN, &warn_to[cnt]);
2027 spin_lock(&transfer_to[cnt]->dq_dqb_lock);
2028 dquot_decr_inodes(transfer_to[cnt], inode_usage);
2029 spin_unlock(&transfer_to[cnt]->dq_dqb_lock);
2034 /* Decrease usage for source structures and update quota pointers */
2035 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
2038 /* Due to IO error we might not have transfer_from[] structure */
2039 if (transfer_from[cnt]) {
2042 spin_lock(&transfer_from[cnt]->dq_dqb_lock);
2043 wtype = info_idq_free(transfer_from[cnt], inode_usage);
2044 if (wtype != QUOTA_NL_NOWARN)
2045 prepare_warning(&warn_from_inodes[cnt],
2046 transfer_from[cnt], wtype);
2047 wtype = info_bdq_free(transfer_from[cnt],
2048 cur_space + rsv_space);
2049 if (wtype != QUOTA_NL_NOWARN)
2050 prepare_warning(&warn_from_space[cnt],
2051 transfer_from[cnt], wtype);
2052 dquot_decr_inodes(transfer_from[cnt], inode_usage);
2053 dquot_decr_space(transfer_from[cnt], cur_space);
2054 dquot_free_reserved_space(transfer_from[cnt],
2056 spin_unlock(&transfer_from[cnt]->dq_dqb_lock);
2058 i_dquot(inode)[cnt] = transfer_to[cnt];
2060 spin_unlock(&inode->i_lock);
2061 spin_unlock(&dq_data_lock);
2063 mark_all_dquot_dirty(transfer_from);
2064 mark_all_dquot_dirty(transfer_to);
2065 flush_warnings(warn_to);
2066 flush_warnings(warn_from_inodes);
2067 flush_warnings(warn_from_space);
2068 /* Pass back references to put */
2069 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
2071 transfer_to[cnt] = transfer_from[cnt];
2074 /* Back out changes we already did */
2075 for (cnt--; cnt >= 0; cnt--) {
2078 spin_lock(&transfer_to[cnt]->dq_dqb_lock);
2079 dquot_decr_inodes(transfer_to[cnt], inode_usage);
2080 dquot_decr_space(transfer_to[cnt], cur_space);
2081 dquot_free_reserved_space(transfer_to[cnt], rsv_space);
2082 spin_unlock(&transfer_to[cnt]->dq_dqb_lock);
2084 spin_unlock(&inode->i_lock);
2085 spin_unlock(&dq_data_lock);
2086 flush_warnings(warn_to);
2089 EXPORT_SYMBOL(__dquot_transfer);
2091 /* Wrapper for transferring ownership of an inode for uid/gid only
2092 * Called from FSXXX_setattr()
2094 int dquot_transfer(struct mnt_idmap *idmap, struct inode *inode,
2095 struct iattr *iattr)
2097 struct dquot *transfer_to[MAXQUOTAS] = {};
2098 struct dquot *dquot;
2099 struct super_block *sb = inode->i_sb;
2102 if (!inode_quota_active(inode))
2105 if (i_uid_needs_update(idmap, iattr, inode)) {
2106 kuid_t kuid = from_vfsuid(idmap, i_user_ns(inode),
2109 dquot = dqget(sb, make_kqid_uid(kuid));
2110 if (IS_ERR(dquot)) {
2111 if (PTR_ERR(dquot) != -ESRCH) {
2112 ret = PTR_ERR(dquot);
2117 transfer_to[USRQUOTA] = dquot;
2119 if (i_gid_needs_update(idmap, iattr, inode)) {
2120 kgid_t kgid = from_vfsgid(idmap, i_user_ns(inode),
2123 dquot = dqget(sb, make_kqid_gid(kgid));
2124 if (IS_ERR(dquot)) {
2125 if (PTR_ERR(dquot) != -ESRCH) {
2126 ret = PTR_ERR(dquot);
2131 transfer_to[GRPQUOTA] = dquot;
2133 ret = __dquot_transfer(inode, transfer_to);
2135 dqput_all(transfer_to);
2138 EXPORT_SYMBOL(dquot_transfer);
2141 * Write info of quota file to disk
2143 int dquot_commit_info(struct super_block *sb, int type)
2145 struct quota_info *dqopt = sb_dqopt(sb);
2147 return dqopt->ops[type]->write_file_info(sb, type);
2149 EXPORT_SYMBOL(dquot_commit_info);
2151 int dquot_get_next_id(struct super_block *sb, struct kqid *qid)
2153 struct quota_info *dqopt = sb_dqopt(sb);
2155 if (!sb_has_quota_active(sb, qid->type))
2157 if (!dqopt->ops[qid->type]->get_next_id)
2159 return dqopt->ops[qid->type]->get_next_id(sb, qid);
2161 EXPORT_SYMBOL(dquot_get_next_id);
2164 * Definitions of diskquota operations.
2166 const struct dquot_operations dquot_operations = {
2167 .write_dquot = dquot_commit,
2168 .acquire_dquot = dquot_acquire,
2169 .release_dquot = dquot_release,
2170 .mark_dirty = dquot_mark_dquot_dirty,
2171 .write_info = dquot_commit_info,
2172 .alloc_dquot = dquot_alloc,
2173 .destroy_dquot = dquot_destroy,
2174 .get_next_id = dquot_get_next_id,
2176 EXPORT_SYMBOL(dquot_operations);
2179 * Generic helper for ->open on filesystems supporting disk quotas.
2181 int dquot_file_open(struct inode *inode, struct file *file)
2185 error = generic_file_open(inode, file);
2186 if (!error && (file->f_mode & FMODE_WRITE))
2187 error = dquot_initialize(inode);
2190 EXPORT_SYMBOL(dquot_file_open);
2192 static void vfs_cleanup_quota_inode(struct super_block *sb, int type)
2194 struct quota_info *dqopt = sb_dqopt(sb);
2195 struct inode *inode = dqopt->files[type];
2199 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) {
2201 inode->i_flags &= ~S_NOQUOTA;
2202 inode_unlock(inode);
2204 dqopt->files[type] = NULL;
2209 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount)
2211 int dquot_disable(struct super_block *sb, int type, unsigned int flags)
2214 struct quota_info *dqopt = sb_dqopt(sb);
2216 /* s_umount should be held in exclusive mode */
2217 if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount)))
2218 up_read(&sb->s_umount);
2220 /* Cannot turn off usage accounting without turning off limits, or
2221 * suspend quotas and simultaneously turn quotas off. */
2222 if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED))
2223 || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED |
2224 DQUOT_USAGE_ENABLED)))
2228 * Skip everything if there's nothing to do. We have to do this because
2229 * sometimes we are called when fill_super() failed and calling
2230 * sync_fs() in such cases does no good.
2232 if (!sb_any_quota_loaded(sb))
2235 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
2236 if (type != -1 && cnt != type)
2238 if (!sb_has_quota_loaded(sb, cnt))
2241 if (flags & DQUOT_SUSPENDED) {
2242 spin_lock(&dq_state_lock);
2244 dquot_state_flag(DQUOT_SUSPENDED, cnt);
2245 spin_unlock(&dq_state_lock);
2247 spin_lock(&dq_state_lock);
2248 dqopt->flags &= ~dquot_state_flag(flags, cnt);
2249 /* Turning off suspended quotas? */
2250 if (!sb_has_quota_loaded(sb, cnt) &&
2251 sb_has_quota_suspended(sb, cnt)) {
2252 dqopt->flags &= ~dquot_state_flag(
2253 DQUOT_SUSPENDED, cnt);
2254 spin_unlock(&dq_state_lock);
2255 vfs_cleanup_quota_inode(sb, cnt);
2258 spin_unlock(&dq_state_lock);
2261 /* We still have to keep quota loaded? */
2262 if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED))
2265 /* Note: these are blocking operations */
2266 drop_dquot_ref(sb, cnt);
2267 invalidate_dquots(sb, cnt);
2269 * Now all dquots should be invalidated, all writes done so we
2270 * should be only users of the info. No locks needed.
2272 if (info_dirty(&dqopt->info[cnt]))
2273 sb->dq_op->write_info(sb, cnt);
2274 if (dqopt->ops[cnt]->free_file_info)
2275 dqopt->ops[cnt]->free_file_info(sb, cnt);
2276 put_quota_format(dqopt->info[cnt].dqi_format);
2277 dqopt->info[cnt].dqi_flags = 0;
2278 dqopt->info[cnt].dqi_igrace = 0;
2279 dqopt->info[cnt].dqi_bgrace = 0;
2280 dqopt->ops[cnt] = NULL;
2283 /* Skip syncing and setting flags if quota files are hidden */
2284 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE)
2287 /* Sync the superblock so that buffers with quota data are written to
2288 * disk (and so userspace sees correct data afterwards). */
2289 if (sb->s_op->sync_fs)
2290 sb->s_op->sync_fs(sb, 1);
2291 sync_blockdev(sb->s_bdev);
2292 /* Now the quota files are just ordinary files and we can set the
2293 * inode flags back. Moreover we discard the pagecache so that
2294 * userspace sees the writes we did bypassing the pagecache. We
2295 * must also discard the blockdev buffers so that we see the
2296 * changes done by userspace on the next quotaon() */
2297 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
2298 if (!sb_has_quota_loaded(sb, cnt) && dqopt->files[cnt]) {
2299 inode_lock(dqopt->files[cnt]);
2300 truncate_inode_pages(&dqopt->files[cnt]->i_data, 0);
2301 inode_unlock(dqopt->files[cnt]);
2304 invalidate_bdev(sb->s_bdev);
2306 /* We are done when suspending quotas */
2307 if (flags & DQUOT_SUSPENDED)
2310 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
2311 if (!sb_has_quota_loaded(sb, cnt))
2312 vfs_cleanup_quota_inode(sb, cnt);
2315 EXPORT_SYMBOL(dquot_disable);
2317 int dquot_quota_off(struct super_block *sb, int type)
2319 return dquot_disable(sb, type,
2320 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
2322 EXPORT_SYMBOL(dquot_quota_off);
2325 * Turn quotas on on a device
2328 static int vfs_setup_quota_inode(struct inode *inode, int type)
2330 struct super_block *sb = inode->i_sb;
2331 struct quota_info *dqopt = sb_dqopt(sb);
2333 if (is_bad_inode(inode))
2335 if (!S_ISREG(inode->i_mode))
2337 if (IS_RDONLY(inode))
2339 if (sb_has_quota_loaded(sb, type))
2342 dqopt->files[type] = igrab(inode);
2343 if (!dqopt->files[type])
2345 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) {
2346 /* We don't want quota and atime on quota files (deadlocks
2347 * possible) Also nobody should write to the file - we use
2348 * special IO operations which ignore the immutable bit. */
2350 inode->i_flags |= S_NOQUOTA;
2351 inode_unlock(inode);
2353 * When S_NOQUOTA is set, remove dquot references as no more
2354 * references can be added
2356 __dquot_drop(inode);
2361 int dquot_load_quota_sb(struct super_block *sb, int type, int format_id,
2364 struct quota_format_type *fmt = find_quota_format(format_id);
2365 struct quota_info *dqopt = sb_dqopt(sb);
2368 lockdep_assert_held_write(&sb->s_umount);
2370 /* Just unsuspend quotas? */
2371 BUG_ON(flags & DQUOT_SUSPENDED);
2375 if (!sb->dq_op || !sb->s_qcop ||
2376 (type == PRJQUOTA && sb->dq_op->get_projid == NULL)) {
2380 /* Filesystems outside of init_user_ns not yet supported */
2381 if (sb->s_user_ns != &init_user_ns) {
2385 /* Usage always has to be set... */
2386 if (!(flags & DQUOT_USAGE_ENABLED)) {
2390 if (sb_has_quota_loaded(sb, type)) {
2395 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) {
2396 /* As we bypass the pagecache we must now flush all the
2397 * dirty data and invalidate caches so that kernel sees
2398 * changes from userspace. It is not enough to just flush
2399 * the quota file since if blocksize < pagesize, invalidation
2400 * of the cache could fail because of other unrelated dirty
2402 sync_filesystem(sb);
2403 invalidate_bdev(sb->s_bdev);
2407 if (!fmt->qf_ops->check_quota_file(sb, type))
2410 dqopt->ops[type] = fmt->qf_ops;
2411 dqopt->info[type].dqi_format = fmt;
2412 dqopt->info[type].dqi_fmt_id = format_id;
2413 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list);
2414 error = dqopt->ops[type]->read_file_info(sb, type);
2417 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) {
2418 spin_lock(&dq_data_lock);
2419 dqopt->info[type].dqi_flags |= DQF_SYS_FILE;
2420 spin_unlock(&dq_data_lock);
2422 spin_lock(&dq_state_lock);
2423 dqopt->flags |= dquot_state_flag(flags, type);
2424 spin_unlock(&dq_state_lock);
2426 error = add_dquot_ref(sb, type);
2428 dquot_disable(sb, type,
2429 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
2433 put_quota_format(fmt);
2437 EXPORT_SYMBOL(dquot_load_quota_sb);
2440 * More powerful function for turning on quotas on given quota inode allowing
2441 * setting of individual quota flags
2443 int dquot_load_quota_inode(struct inode *inode, int type, int format_id,
2448 err = vfs_setup_quota_inode(inode, type);
2451 err = dquot_load_quota_sb(inode->i_sb, type, format_id, flags);
2453 vfs_cleanup_quota_inode(inode->i_sb, type);
2456 EXPORT_SYMBOL(dquot_load_quota_inode);
2458 /* Reenable quotas on remount RW */
2459 int dquot_resume(struct super_block *sb, int type)
2461 struct quota_info *dqopt = sb_dqopt(sb);
2465 /* s_umount should be held in exclusive mode */
2466 if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount)))
2467 up_read(&sb->s_umount);
2469 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
2470 if (type != -1 && cnt != type)
2472 if (!sb_has_quota_suspended(sb, cnt))
2475 spin_lock(&dq_state_lock);
2476 flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED |
2477 DQUOT_LIMITS_ENABLED,
2479 dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, cnt);
2480 spin_unlock(&dq_state_lock);
2482 flags = dquot_generic_flag(flags, cnt);
2483 ret = dquot_load_quota_sb(sb, cnt, dqopt->info[cnt].dqi_fmt_id,
2486 vfs_cleanup_quota_inode(sb, cnt);
2491 EXPORT_SYMBOL(dquot_resume);
2493 int dquot_quota_on(struct super_block *sb, int type, int format_id,
2494 const struct path *path)
2496 int error = security_quota_on(path->dentry);
2499 /* Quota file not on the same filesystem? */
2500 if (path->dentry->d_sb != sb)
2503 error = dquot_load_quota_inode(d_inode(path->dentry), type,
2504 format_id, DQUOT_USAGE_ENABLED |
2505 DQUOT_LIMITS_ENABLED);
2508 EXPORT_SYMBOL(dquot_quota_on);
2511 * This function is used when filesystem needs to initialize quotas
2512 * during mount time.
2514 int dquot_quota_on_mount(struct super_block *sb, char *qf_name,
2515 int format_id, int type)
2517 struct dentry *dentry;
2520 dentry = lookup_positive_unlocked(qf_name, sb->s_root, strlen(qf_name));
2522 return PTR_ERR(dentry);
2524 error = security_quota_on(dentry);
2526 error = dquot_load_quota_inode(d_inode(dentry), type, format_id,
2527 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
2532 EXPORT_SYMBOL(dquot_quota_on_mount);
2534 static int dquot_quota_enable(struct super_block *sb, unsigned int flags)
2538 struct quota_info *dqopt = sb_dqopt(sb);
2540 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE))
2542 /* Accounting cannot be turned on while fs is mounted */
2543 flags &= ~(FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT | FS_QUOTA_PDQ_ACCT);
2546 for (type = 0; type < MAXQUOTAS; type++) {
2547 if (!(flags & qtype_enforce_flag(type)))
2549 /* Can't enforce without accounting */
2550 if (!sb_has_quota_usage_enabled(sb, type)) {
2554 if (sb_has_quota_limits_enabled(sb, type)) {
2558 spin_lock(&dq_state_lock);
2559 dqopt->flags |= dquot_state_flag(DQUOT_LIMITS_ENABLED, type);
2560 spin_unlock(&dq_state_lock);
2564 /* Backout enforcement enablement we already did */
2565 for (type--; type >= 0; type--) {
2566 if (flags & qtype_enforce_flag(type))
2567 dquot_disable(sb, type, DQUOT_LIMITS_ENABLED);
2569 /* Error code translation for better compatibility with XFS */
2575 static int dquot_quota_disable(struct super_block *sb, unsigned int flags)
2579 struct quota_info *dqopt = sb_dqopt(sb);
2581 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE))
2584 * We don't support turning off accounting via quotactl. In principle
2585 * quota infrastructure can do this but filesystems don't expect
2586 * userspace to be able to do it.
2589 (FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT | FS_QUOTA_PDQ_ACCT))
2592 /* Filter out limits not enabled */
2593 for (type = 0; type < MAXQUOTAS; type++)
2594 if (!sb_has_quota_limits_enabled(sb, type))
2595 flags &= ~qtype_enforce_flag(type);
2599 for (type = 0; type < MAXQUOTAS; type++) {
2600 if (flags & qtype_enforce_flag(type)) {
2601 ret = dquot_disable(sb, type, DQUOT_LIMITS_ENABLED);
2608 /* Backout enforcement disabling we already did */
2609 for (type--; type >= 0; type--) {
2610 if (flags & qtype_enforce_flag(type)) {
2611 spin_lock(&dq_state_lock);
2613 dquot_state_flag(DQUOT_LIMITS_ENABLED, type);
2614 spin_unlock(&dq_state_lock);
2620 /* Generic routine for getting common part of quota structure */
2621 static void do_get_dqblk(struct dquot *dquot, struct qc_dqblk *di)
2623 struct mem_dqblk *dm = &dquot->dq_dqb;
2625 memset(di, 0, sizeof(*di));
2626 spin_lock(&dquot->dq_dqb_lock);
2627 di->d_spc_hardlimit = dm->dqb_bhardlimit;
2628 di->d_spc_softlimit = dm->dqb_bsoftlimit;
2629 di->d_ino_hardlimit = dm->dqb_ihardlimit;
2630 di->d_ino_softlimit = dm->dqb_isoftlimit;
2631 di->d_space = dm->dqb_curspace + dm->dqb_rsvspace;
2632 di->d_ino_count = dm->dqb_curinodes;
2633 di->d_spc_timer = dm->dqb_btime;
2634 di->d_ino_timer = dm->dqb_itime;
2635 spin_unlock(&dquot->dq_dqb_lock);
2638 int dquot_get_dqblk(struct super_block *sb, struct kqid qid,
2639 struct qc_dqblk *di)
2641 struct dquot *dquot;
2643 dquot = dqget(sb, qid);
2645 return PTR_ERR(dquot);
2646 do_get_dqblk(dquot, di);
2651 EXPORT_SYMBOL(dquot_get_dqblk);
2653 int dquot_get_next_dqblk(struct super_block *sb, struct kqid *qid,
2654 struct qc_dqblk *di)
2656 struct dquot *dquot;
2659 if (!sb->dq_op->get_next_id)
2661 err = sb->dq_op->get_next_id(sb, qid);
2664 dquot = dqget(sb, *qid);
2666 return PTR_ERR(dquot);
2667 do_get_dqblk(dquot, di);
2672 EXPORT_SYMBOL(dquot_get_next_dqblk);
2674 #define VFS_QC_MASK \
2675 (QC_SPACE | QC_SPC_SOFT | QC_SPC_HARD | \
2676 QC_INO_COUNT | QC_INO_SOFT | QC_INO_HARD | \
2677 QC_SPC_TIMER | QC_INO_TIMER)
2679 /* Generic routine for setting common part of quota structure */
2680 static int do_set_dqblk(struct dquot *dquot, struct qc_dqblk *di)
2682 struct mem_dqblk *dm = &dquot->dq_dqb;
2683 int check_blim = 0, check_ilim = 0;
2684 struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type];
2686 if (di->d_fieldmask & ~VFS_QC_MASK)
2689 if (((di->d_fieldmask & QC_SPC_SOFT) &&
2690 di->d_spc_softlimit > dqi->dqi_max_spc_limit) ||
2691 ((di->d_fieldmask & QC_SPC_HARD) &&
2692 di->d_spc_hardlimit > dqi->dqi_max_spc_limit) ||
2693 ((di->d_fieldmask & QC_INO_SOFT) &&
2694 (di->d_ino_softlimit > dqi->dqi_max_ino_limit)) ||
2695 ((di->d_fieldmask & QC_INO_HARD) &&
2696 (di->d_ino_hardlimit > dqi->dqi_max_ino_limit)))
2699 spin_lock(&dquot->dq_dqb_lock);
2700 if (di->d_fieldmask & QC_SPACE) {
2701 dm->dqb_curspace = di->d_space - dm->dqb_rsvspace;
2703 set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags);
2706 if (di->d_fieldmask & QC_SPC_SOFT)
2707 dm->dqb_bsoftlimit = di->d_spc_softlimit;
2708 if (di->d_fieldmask & QC_SPC_HARD)
2709 dm->dqb_bhardlimit = di->d_spc_hardlimit;
2710 if (di->d_fieldmask & (QC_SPC_SOFT | QC_SPC_HARD)) {
2712 set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags);
2715 if (di->d_fieldmask & QC_INO_COUNT) {
2716 dm->dqb_curinodes = di->d_ino_count;
2718 set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags);
2721 if (di->d_fieldmask & QC_INO_SOFT)
2722 dm->dqb_isoftlimit = di->d_ino_softlimit;
2723 if (di->d_fieldmask & QC_INO_HARD)
2724 dm->dqb_ihardlimit = di->d_ino_hardlimit;
2725 if (di->d_fieldmask & (QC_INO_SOFT | QC_INO_HARD)) {
2727 set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags);
2730 if (di->d_fieldmask & QC_SPC_TIMER) {
2731 dm->dqb_btime = di->d_spc_timer;
2733 set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags);
2736 if (di->d_fieldmask & QC_INO_TIMER) {
2737 dm->dqb_itime = di->d_ino_timer;
2739 set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags);
2743 if (!dm->dqb_bsoftlimit ||
2744 dm->dqb_curspace + dm->dqb_rsvspace <= dm->dqb_bsoftlimit) {
2746 clear_bit(DQ_BLKS_B, &dquot->dq_flags);
2747 } else if (!(di->d_fieldmask & QC_SPC_TIMER))
2748 /* Set grace only if user hasn't provided his own... */
2749 dm->dqb_btime = ktime_get_real_seconds() + dqi->dqi_bgrace;
2752 if (!dm->dqb_isoftlimit ||
2753 dm->dqb_curinodes <= dm->dqb_isoftlimit) {
2755 clear_bit(DQ_INODES_B, &dquot->dq_flags);
2756 } else if (!(di->d_fieldmask & QC_INO_TIMER))
2757 /* Set grace only if user hasn't provided his own... */
2758 dm->dqb_itime = ktime_get_real_seconds() + dqi->dqi_igrace;
2760 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit ||
2762 clear_bit(DQ_FAKE_B, &dquot->dq_flags);
2764 set_bit(DQ_FAKE_B, &dquot->dq_flags);
2765 spin_unlock(&dquot->dq_dqb_lock);
2766 mark_dquot_dirty(dquot);
2771 int dquot_set_dqblk(struct super_block *sb, struct kqid qid,
2772 struct qc_dqblk *di)
2774 struct dquot *dquot;
2777 dquot = dqget(sb, qid);
2778 if (IS_ERR(dquot)) {
2779 rc = PTR_ERR(dquot);
2782 rc = do_set_dqblk(dquot, di);
2787 EXPORT_SYMBOL(dquot_set_dqblk);
2789 /* Generic routine for getting common part of quota file information */
2790 int dquot_get_state(struct super_block *sb, struct qc_state *state)
2792 struct mem_dqinfo *mi;
2793 struct qc_type_state *tstate;
2794 struct quota_info *dqopt = sb_dqopt(sb);
2797 memset(state, 0, sizeof(*state));
2798 for (type = 0; type < MAXQUOTAS; type++) {
2799 if (!sb_has_quota_active(sb, type))
2801 tstate = state->s_state + type;
2802 mi = sb_dqopt(sb)->info + type;
2803 tstate->flags = QCI_ACCT_ENABLED;
2804 spin_lock(&dq_data_lock);
2805 if (mi->dqi_flags & DQF_SYS_FILE)
2806 tstate->flags |= QCI_SYSFILE;
2807 if (mi->dqi_flags & DQF_ROOT_SQUASH)
2808 tstate->flags |= QCI_ROOT_SQUASH;
2809 if (sb_has_quota_limits_enabled(sb, type))
2810 tstate->flags |= QCI_LIMITS_ENFORCED;
2811 tstate->spc_timelimit = mi->dqi_bgrace;
2812 tstate->ino_timelimit = mi->dqi_igrace;
2813 if (dqopt->files[type]) {
2814 tstate->ino = dqopt->files[type]->i_ino;
2815 tstate->blocks = dqopt->files[type]->i_blocks;
2817 tstate->nextents = 1; /* We don't know... */
2818 spin_unlock(&dq_data_lock);
2822 EXPORT_SYMBOL(dquot_get_state);
2824 /* Generic routine for setting common part of quota file information */
2825 int dquot_set_dqinfo(struct super_block *sb, int type, struct qc_info *ii)
2827 struct mem_dqinfo *mi;
2829 if ((ii->i_fieldmask & QC_WARNS_MASK) ||
2830 (ii->i_fieldmask & QC_RT_SPC_TIMER))
2832 if (!sb_has_quota_active(sb, type))
2834 mi = sb_dqopt(sb)->info + type;
2835 if (ii->i_fieldmask & QC_FLAGS) {
2836 if ((ii->i_flags & QCI_ROOT_SQUASH &&
2837 mi->dqi_format->qf_fmt_id != QFMT_VFS_OLD))
2840 spin_lock(&dq_data_lock);
2841 if (ii->i_fieldmask & QC_SPC_TIMER)
2842 mi->dqi_bgrace = ii->i_spc_timelimit;
2843 if (ii->i_fieldmask & QC_INO_TIMER)
2844 mi->dqi_igrace = ii->i_ino_timelimit;
2845 if (ii->i_fieldmask & QC_FLAGS) {
2846 if (ii->i_flags & QCI_ROOT_SQUASH)
2847 mi->dqi_flags |= DQF_ROOT_SQUASH;
2849 mi->dqi_flags &= ~DQF_ROOT_SQUASH;
2851 spin_unlock(&dq_data_lock);
2852 mark_info_dirty(sb, type);
2853 /* Force write to disk */
2854 return sb->dq_op->write_info(sb, type);
2856 EXPORT_SYMBOL(dquot_set_dqinfo);
2858 const struct quotactl_ops dquot_quotactl_sysfile_ops = {
2859 .quota_enable = dquot_quota_enable,
2860 .quota_disable = dquot_quota_disable,
2861 .quota_sync = dquot_quota_sync,
2862 .get_state = dquot_get_state,
2863 .set_info = dquot_set_dqinfo,
2864 .get_dqblk = dquot_get_dqblk,
2865 .get_nextdqblk = dquot_get_next_dqblk,
2866 .set_dqblk = dquot_set_dqblk
2868 EXPORT_SYMBOL(dquot_quotactl_sysfile_ops);
2870 static int do_proc_dqstats(struct ctl_table *table, int write,
2871 void *buffer, size_t *lenp, loff_t *ppos)
2873 unsigned int type = (unsigned long *)table->data - dqstats.stat;
2874 s64 value = percpu_counter_sum(&dqstats.counter[type]);
2876 /* Filter negative values for non-monotonic counters */
2877 if (value < 0 && (type == DQST_ALLOC_DQUOTS ||
2878 type == DQST_FREE_DQUOTS))
2881 /* Update global table */
2882 dqstats.stat[type] = value;
2883 return proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
2886 static struct ctl_table fs_dqstats_table[] = {
2888 .procname = "lookups",
2889 .data = &dqstats.stat[DQST_LOOKUPS],
2890 .maxlen = sizeof(unsigned long),
2892 .proc_handler = do_proc_dqstats,
2895 .procname = "drops",
2896 .data = &dqstats.stat[DQST_DROPS],
2897 .maxlen = sizeof(unsigned long),
2899 .proc_handler = do_proc_dqstats,
2902 .procname = "reads",
2903 .data = &dqstats.stat[DQST_READS],
2904 .maxlen = sizeof(unsigned long),
2906 .proc_handler = do_proc_dqstats,
2909 .procname = "writes",
2910 .data = &dqstats.stat[DQST_WRITES],
2911 .maxlen = sizeof(unsigned long),
2913 .proc_handler = do_proc_dqstats,
2916 .procname = "cache_hits",
2917 .data = &dqstats.stat[DQST_CACHE_HITS],
2918 .maxlen = sizeof(unsigned long),
2920 .proc_handler = do_proc_dqstats,
2923 .procname = "allocated_dquots",
2924 .data = &dqstats.stat[DQST_ALLOC_DQUOTS],
2925 .maxlen = sizeof(unsigned long),
2927 .proc_handler = do_proc_dqstats,
2930 .procname = "free_dquots",
2931 .data = &dqstats.stat[DQST_FREE_DQUOTS],
2932 .maxlen = sizeof(unsigned long),
2934 .proc_handler = do_proc_dqstats,
2937 .procname = "syncs",
2938 .data = &dqstats.stat[DQST_SYNCS],
2939 .maxlen = sizeof(unsigned long),
2941 .proc_handler = do_proc_dqstats,
2943 #ifdef CONFIG_PRINT_QUOTA_WARNING
2945 .procname = "warnings",
2946 .data = &flag_print_warnings,
2947 .maxlen = sizeof(int),
2949 .proc_handler = proc_dointvec,
2955 static int __init dquot_init(void)
2958 unsigned long nr_hash, order;
2960 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__);
2962 register_sysctl_init("fs/quota", fs_dqstats_table);
2964 dquot_cachep = kmem_cache_create("dquot",
2965 sizeof(struct dquot), sizeof(unsigned long) * 4,
2966 (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
2967 SLAB_MEM_SPREAD|SLAB_PANIC),
2971 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_KERNEL, order);
2973 panic("Cannot create dquot hash table");
2975 for (i = 0; i < _DQST_DQSTAT_LAST; i++) {
2976 ret = percpu_counter_init(&dqstats.counter[i], 0, GFP_KERNEL);
2978 panic("Cannot create dquot stat counters");
2981 /* Find power-of-two hlist_heads which can fit into allocation */
2982 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head);
2983 dq_hash_bits = ilog2(nr_hash);
2985 nr_hash = 1UL << dq_hash_bits;
2986 dq_hash_mask = nr_hash - 1;
2987 for (i = 0; i < nr_hash; i++)
2988 INIT_HLIST_HEAD(dquot_hash + i);
2990 pr_info("VFS: Dquot-cache hash table entries: %ld (order %ld,"
2991 " %ld bytes)\n", nr_hash, order, (PAGE_SIZE << order));
2993 if (register_shrinker(&dqcache_shrinker, "dquota-cache"))
2994 panic("Cannot register dquot shrinker");
2998 fs_initcall(dquot_init);