1 // SPDX-License-Identifier: GPL-2.0-only
3 * (C) 1997 Linus Torvalds
4 * (C) 1999 Andrea Arcangeli <andrea@suse.de> (dynamic inode allocation)
6 #include <linux/export.h>
9 #include <linux/backing-dev.h>
10 #include <linux/hash.h>
11 #include <linux/swap.h>
12 #include <linux/security.h>
13 #include <linux/cdev.h>
14 #include <linux/memblock.h>
15 #include <linux/fsnotify.h>
16 #include <linux/mount.h>
17 #include <linux/posix_acl.h>
18 #include <linux/prefetch.h>
19 #include <linux/buffer_head.h> /* for inode_has_buffers */
20 #include <linux/ratelimit.h>
21 #include <linux/list_lru.h>
22 #include <linux/iversion.h>
23 #include <trace/events/writeback.h>
27 * Inode locking rules:
29 * inode->i_lock protects:
30 * inode->i_state, inode->i_hash, __iget()
31 * Inode LRU list locks protect:
32 * inode->i_sb->s_inode_lru, inode->i_lru
33 * inode->i_sb->s_inode_list_lock protects:
34 * inode->i_sb->s_inodes, inode->i_sb_list
35 * bdi->wb.list_lock protects:
36 * bdi->wb.b_{dirty,io,more_io,dirty_time}, inode->i_io_list
37 * inode_hash_lock protects:
38 * inode_hashtable, inode->i_hash
42 * inode->i_sb->s_inode_list_lock
44 * Inode LRU list locks
50 * inode->i_sb->s_inode_list_lock
57 static unsigned int i_hash_mask __read_mostly
;
58 static unsigned int i_hash_shift __read_mostly
;
59 static struct hlist_head
*inode_hashtable __read_mostly
;
60 static __cacheline_aligned_in_smp
DEFINE_SPINLOCK(inode_hash_lock
);
63 * Empty aops. Can be used for the cases where the user does not
64 * define any of the address_space operations.
66 const struct address_space_operations empty_aops
= {
68 EXPORT_SYMBOL(empty_aops
);
70 static DEFINE_PER_CPU(unsigned long, nr_inodes
);
71 static DEFINE_PER_CPU(unsigned long, nr_unused
);
73 static struct kmem_cache
*inode_cachep __read_mostly
;
75 static long get_nr_inodes(void)
79 for_each_possible_cpu(i
)
80 sum
+= per_cpu(nr_inodes
, i
);
81 return sum
< 0 ? 0 : sum
;
84 static inline long get_nr_inodes_unused(void)
88 for_each_possible_cpu(i
)
89 sum
+= per_cpu(nr_unused
, i
);
90 return sum
< 0 ? 0 : sum
;
93 long get_nr_dirty_inodes(void)
95 /* not actually dirty inodes, but a wild approximation */
96 long nr_dirty
= get_nr_inodes() - get_nr_inodes_unused();
97 return nr_dirty
> 0 ? nr_dirty
: 0;
101 * Handle nr_inode sysctl
105 * Statistics gathering..
107 static struct inodes_stat_t inodes_stat
;
109 static int proc_nr_inodes(struct ctl_table
*table
, int write
, void *buffer
,
110 size_t *lenp
, loff_t
*ppos
)
112 inodes_stat
.nr_inodes
= get_nr_inodes();
113 inodes_stat
.nr_unused
= get_nr_inodes_unused();
114 return proc_doulongvec_minmax(table
, write
, buffer
, lenp
, ppos
);
117 static struct ctl_table inodes_sysctls
[] = {
119 .procname
= "inode-nr",
120 .data
= &inodes_stat
,
121 .maxlen
= 2*sizeof(long),
123 .proc_handler
= proc_nr_inodes
,
126 .procname
= "inode-state",
127 .data
= &inodes_stat
,
128 .maxlen
= 7*sizeof(long),
130 .proc_handler
= proc_nr_inodes
,
135 static int __init
init_fs_inode_sysctls(void)
137 register_sysctl_init("fs", inodes_sysctls
);
140 early_initcall(init_fs_inode_sysctls
);
143 static int no_open(struct inode
*inode
, struct file
*file
)
149 * inode_init_always - perform inode structure initialisation
150 * @sb: superblock inode belongs to
151 * @inode: inode to initialise
153 * These are initializations that need to be done on every inode
154 * allocation as the fields are not initialised by slab allocation.
156 int inode_init_always(struct super_block
*sb
, struct inode
*inode
)
158 static const struct inode_operations empty_iops
;
159 static const struct file_operations no_open_fops
= {.open
= no_open
};
160 struct address_space
*const mapping
= &inode
->i_data
;
163 inode
->i_blkbits
= sb
->s_blocksize_bits
;
165 atomic64_set(&inode
->i_sequence
, 0);
166 atomic_set(&inode
->i_count
, 1);
167 inode
->i_op
= &empty_iops
;
168 inode
->i_fop
= &no_open_fops
;
170 inode
->__i_nlink
= 1;
171 inode
->i_opflags
= 0;
173 inode
->i_opflags
|= IOP_XATTR
;
174 i_uid_write(inode
, 0);
175 i_gid_write(inode
, 0);
176 atomic_set(&inode
->i_writecount
, 0);
178 inode
->i_write_hint
= WRITE_LIFE_NOT_SET
;
181 inode
->i_generation
= 0;
182 inode
->i_pipe
= NULL
;
183 inode
->i_cdev
= NULL
;
184 inode
->i_link
= NULL
;
185 inode
->i_dir_seq
= 0;
187 inode
->dirtied_when
= 0;
189 #ifdef CONFIG_CGROUP_WRITEBACK
190 inode
->i_wb_frn_winner
= 0;
191 inode
->i_wb_frn_avg_time
= 0;
192 inode
->i_wb_frn_history
= 0;
195 if (security_inode_alloc(inode
))
197 spin_lock_init(&inode
->i_lock
);
198 lockdep_set_class(&inode
->i_lock
, &sb
->s_type
->i_lock_key
);
200 init_rwsem(&inode
->i_rwsem
);
201 lockdep_set_class(&inode
->i_rwsem
, &sb
->s_type
->i_mutex_key
);
203 atomic_set(&inode
->i_dio_count
, 0);
205 mapping
->a_ops
= &empty_aops
;
206 mapping
->host
= inode
;
209 atomic_set(&mapping
->i_mmap_writable
, 0);
210 #ifdef CONFIG_READ_ONLY_THP_FOR_FS
211 atomic_set(&mapping
->nr_thps
, 0);
213 mapping_set_gfp_mask(mapping
, GFP_HIGHUSER_MOVABLE
);
214 mapping
->private_data
= NULL
;
215 mapping
->writeback_index
= 0;
216 init_rwsem(&mapping
->invalidate_lock
);
217 lockdep_set_class_and_name(&mapping
->invalidate_lock
,
218 &sb
->s_type
->invalidate_lock_key
,
219 "mapping.invalidate_lock");
220 inode
->i_private
= NULL
;
221 inode
->i_mapping
= mapping
;
222 INIT_HLIST_HEAD(&inode
->i_dentry
); /* buggered by rcu freeing */
223 #ifdef CONFIG_FS_POSIX_ACL
224 inode
->i_acl
= inode
->i_default_acl
= ACL_NOT_CACHED
;
227 #ifdef CONFIG_FSNOTIFY
228 inode
->i_fsnotify_mask
= 0;
230 inode
->i_flctx
= NULL
;
231 this_cpu_inc(nr_inodes
);
237 EXPORT_SYMBOL(inode_init_always
);
239 void free_inode_nonrcu(struct inode
*inode
)
241 kmem_cache_free(inode_cachep
, inode
);
243 EXPORT_SYMBOL(free_inode_nonrcu
);
245 static void i_callback(struct rcu_head
*head
)
247 struct inode
*inode
= container_of(head
, struct inode
, i_rcu
);
248 if (inode
->free_inode
)
249 inode
->free_inode(inode
);
251 free_inode_nonrcu(inode
);
254 static struct inode
*alloc_inode(struct super_block
*sb
)
256 const struct super_operations
*ops
= sb
->s_op
;
259 if (ops
->alloc_inode
)
260 inode
= ops
->alloc_inode(sb
);
262 inode
= alloc_inode_sb(sb
, inode_cachep
, GFP_KERNEL
);
267 if (unlikely(inode_init_always(sb
, inode
))) {
268 if (ops
->destroy_inode
) {
269 ops
->destroy_inode(inode
);
270 if (!ops
->free_inode
)
273 inode
->free_inode
= ops
->free_inode
;
274 i_callback(&inode
->i_rcu
);
281 void __destroy_inode(struct inode
*inode
)
283 BUG_ON(inode_has_buffers(inode
));
284 inode_detach_wb(inode
);
285 security_inode_free(inode
);
286 fsnotify_inode_delete(inode
);
287 locks_free_lock_context(inode
);
288 if (!inode
->i_nlink
) {
289 WARN_ON(atomic_long_read(&inode
->i_sb
->s_remove_count
) == 0);
290 atomic_long_dec(&inode
->i_sb
->s_remove_count
);
293 #ifdef CONFIG_FS_POSIX_ACL
294 if (inode
->i_acl
&& !is_uncached_acl(inode
->i_acl
))
295 posix_acl_release(inode
->i_acl
);
296 if (inode
->i_default_acl
&& !is_uncached_acl(inode
->i_default_acl
))
297 posix_acl_release(inode
->i_default_acl
);
299 this_cpu_dec(nr_inodes
);
301 EXPORT_SYMBOL(__destroy_inode
);
303 static void destroy_inode(struct inode
*inode
)
305 const struct super_operations
*ops
= inode
->i_sb
->s_op
;
307 BUG_ON(!list_empty(&inode
->i_lru
));
308 __destroy_inode(inode
);
309 if (ops
->destroy_inode
) {
310 ops
->destroy_inode(inode
);
311 if (!ops
->free_inode
)
314 inode
->free_inode
= ops
->free_inode
;
315 call_rcu(&inode
->i_rcu
, i_callback
);
319 * drop_nlink - directly drop an inode's link count
322 * This is a low-level filesystem helper to replace any
323 * direct filesystem manipulation of i_nlink. In cases
324 * where we are attempting to track writes to the
325 * filesystem, a decrement to zero means an imminent
326 * write when the file is truncated and actually unlinked
329 void drop_nlink(struct inode
*inode
)
331 WARN_ON(inode
->i_nlink
== 0);
334 atomic_long_inc(&inode
->i_sb
->s_remove_count
);
336 EXPORT_SYMBOL(drop_nlink
);
339 * clear_nlink - directly zero an inode's link count
342 * This is a low-level filesystem helper to replace any
343 * direct filesystem manipulation of i_nlink. See
344 * drop_nlink() for why we care about i_nlink hitting zero.
346 void clear_nlink(struct inode
*inode
)
348 if (inode
->i_nlink
) {
349 inode
->__i_nlink
= 0;
350 atomic_long_inc(&inode
->i_sb
->s_remove_count
);
353 EXPORT_SYMBOL(clear_nlink
);
356 * set_nlink - directly set an inode's link count
358 * @nlink: new nlink (should be non-zero)
360 * This is a low-level filesystem helper to replace any
361 * direct filesystem manipulation of i_nlink.
363 void set_nlink(struct inode
*inode
, unsigned int nlink
)
368 /* Yes, some filesystems do change nlink from zero to one */
369 if (inode
->i_nlink
== 0)
370 atomic_long_dec(&inode
->i_sb
->s_remove_count
);
372 inode
->__i_nlink
= nlink
;
375 EXPORT_SYMBOL(set_nlink
);
378 * inc_nlink - directly increment an inode's link count
381 * This is a low-level filesystem helper to replace any
382 * direct filesystem manipulation of i_nlink. Currently,
383 * it is only here for parity with dec_nlink().
385 void inc_nlink(struct inode
*inode
)
387 if (unlikely(inode
->i_nlink
== 0)) {
388 WARN_ON(!(inode
->i_state
& I_LINKABLE
));
389 atomic_long_dec(&inode
->i_sb
->s_remove_count
);
394 EXPORT_SYMBOL(inc_nlink
);
396 static void __address_space_init_once(struct address_space
*mapping
)
398 xa_init_flags(&mapping
->i_pages
, XA_FLAGS_LOCK_IRQ
| XA_FLAGS_ACCOUNT
);
399 init_rwsem(&mapping
->i_mmap_rwsem
);
400 INIT_LIST_HEAD(&mapping
->private_list
);
401 spin_lock_init(&mapping
->private_lock
);
402 mapping
->i_mmap
= RB_ROOT_CACHED
;
405 void address_space_init_once(struct address_space
*mapping
)
407 memset(mapping
, 0, sizeof(*mapping
));
408 __address_space_init_once(mapping
);
410 EXPORT_SYMBOL(address_space_init_once
);
413 * These are initializations that only need to be done
414 * once, because the fields are idempotent across use
415 * of the inode, so let the slab aware of that.
417 void inode_init_once(struct inode
*inode
)
419 memset(inode
, 0, sizeof(*inode
));
420 INIT_HLIST_NODE(&inode
->i_hash
);
421 INIT_LIST_HEAD(&inode
->i_devices
);
422 INIT_LIST_HEAD(&inode
->i_io_list
);
423 INIT_LIST_HEAD(&inode
->i_wb_list
);
424 INIT_LIST_HEAD(&inode
->i_lru
);
425 __address_space_init_once(&inode
->i_data
);
426 i_size_ordered_init(inode
);
428 EXPORT_SYMBOL(inode_init_once
);
430 static void init_once(void *foo
)
432 struct inode
*inode
= (struct inode
*) foo
;
434 inode_init_once(inode
);
438 * inode->i_lock must be held
440 void __iget(struct inode
*inode
)
442 atomic_inc(&inode
->i_count
);
446 * get additional reference to inode; caller must already hold one.
448 void ihold(struct inode
*inode
)
450 WARN_ON(atomic_inc_return(&inode
->i_count
) < 2);
452 EXPORT_SYMBOL(ihold
);
454 static void __inode_add_lru(struct inode
*inode
, bool rotate
)
456 if (inode
->i_state
& (I_DIRTY_ALL
| I_SYNC
| I_FREEING
| I_WILL_FREE
))
458 if (atomic_read(&inode
->i_count
))
460 if (!(inode
->i_sb
->s_flags
& SB_ACTIVE
))
462 if (!mapping_shrinkable(&inode
->i_data
))
465 if (list_lru_add(&inode
->i_sb
->s_inode_lru
, &inode
->i_lru
))
466 this_cpu_inc(nr_unused
);
468 inode
->i_state
|= I_REFERENCED
;
472 * Add inode to LRU if needed (inode is unused and clean).
474 * Needs inode->i_lock held.
476 void inode_add_lru(struct inode
*inode
)
478 __inode_add_lru(inode
, false);
481 static void inode_lru_list_del(struct inode
*inode
)
483 if (list_lru_del(&inode
->i_sb
->s_inode_lru
, &inode
->i_lru
))
484 this_cpu_dec(nr_unused
);
488 * inode_sb_list_add - add inode to the superblock list of inodes
489 * @inode: inode to add
491 void inode_sb_list_add(struct inode
*inode
)
493 spin_lock(&inode
->i_sb
->s_inode_list_lock
);
494 list_add(&inode
->i_sb_list
, &inode
->i_sb
->s_inodes
);
495 spin_unlock(&inode
->i_sb
->s_inode_list_lock
);
497 EXPORT_SYMBOL_GPL(inode_sb_list_add
);
499 static inline void inode_sb_list_del(struct inode
*inode
)
501 if (!list_empty(&inode
->i_sb_list
)) {
502 spin_lock(&inode
->i_sb
->s_inode_list_lock
);
503 list_del_init(&inode
->i_sb_list
);
504 spin_unlock(&inode
->i_sb
->s_inode_list_lock
);
508 static unsigned long hash(struct super_block
*sb
, unsigned long hashval
)
512 tmp
= (hashval
* (unsigned long)sb
) ^ (GOLDEN_RATIO_PRIME
+ hashval
) /
514 tmp
= tmp
^ ((tmp
^ GOLDEN_RATIO_PRIME
) >> i_hash_shift
);
515 return tmp
& i_hash_mask
;
519 * __insert_inode_hash - hash an inode
520 * @inode: unhashed inode
521 * @hashval: unsigned long value used to locate this object in the
524 * Add an inode to the inode hash for this superblock.
526 void __insert_inode_hash(struct inode
*inode
, unsigned long hashval
)
528 struct hlist_head
*b
= inode_hashtable
+ hash(inode
->i_sb
, hashval
);
530 spin_lock(&inode_hash_lock
);
531 spin_lock(&inode
->i_lock
);
532 hlist_add_head_rcu(&inode
->i_hash
, b
);
533 spin_unlock(&inode
->i_lock
);
534 spin_unlock(&inode_hash_lock
);
536 EXPORT_SYMBOL(__insert_inode_hash
);
539 * __remove_inode_hash - remove an inode from the hash
540 * @inode: inode to unhash
542 * Remove an inode from the superblock.
544 void __remove_inode_hash(struct inode
*inode
)
546 spin_lock(&inode_hash_lock
);
547 spin_lock(&inode
->i_lock
);
548 hlist_del_init_rcu(&inode
->i_hash
);
549 spin_unlock(&inode
->i_lock
);
550 spin_unlock(&inode_hash_lock
);
552 EXPORT_SYMBOL(__remove_inode_hash
);
554 void dump_mapping(const struct address_space
*mapping
)
557 const struct address_space_operations
*a_ops
;
558 struct hlist_node
*dentry_first
;
559 struct dentry
*dentry_ptr
;
560 struct dentry dentry
;
564 * If mapping is an invalid pointer, we don't want to crash
565 * accessing it, so probe everything depending on it carefully.
567 if (get_kernel_nofault(host
, &mapping
->host
) ||
568 get_kernel_nofault(a_ops
, &mapping
->a_ops
)) {
569 pr_warn("invalid mapping:%px\n", mapping
);
574 pr_warn("aops:%ps\n", a_ops
);
578 if (get_kernel_nofault(dentry_first
, &host
->i_dentry
.first
) ||
579 get_kernel_nofault(ino
, &host
->i_ino
)) {
580 pr_warn("aops:%ps invalid inode:%px\n", a_ops
, host
);
585 pr_warn("aops:%ps ino:%lx\n", a_ops
, ino
);
589 dentry_ptr
= container_of(dentry_first
, struct dentry
, d_u
.d_alias
);
590 if (get_kernel_nofault(dentry
, dentry_ptr
)) {
591 pr_warn("aops:%ps ino:%lx invalid dentry:%px\n",
592 a_ops
, ino
, dentry_ptr
);
597 * if dentry is corrupted, the %pd handler may still crash,
598 * but it's unlikely that we reach here with a corrupt mapping
600 pr_warn("aops:%ps ino:%lx dentry name:\"%pd\"\n", a_ops
, ino
, &dentry
);
603 void clear_inode(struct inode
*inode
)
606 * We have to cycle the i_pages lock here because reclaim can be in the
607 * process of removing the last page (in __delete_from_page_cache())
608 * and we must not free the mapping under it.
610 xa_lock_irq(&inode
->i_data
.i_pages
);
611 BUG_ON(inode
->i_data
.nrpages
);
613 * Almost always, mapping_empty(&inode->i_data) here; but there are
614 * two known and long-standing ways in which nodes may get left behind
615 * (when deep radix-tree node allocation failed partway; or when THP
616 * collapse_file() failed). Until those two known cases are cleaned up,
617 * or a cleanup function is called here, do not BUG_ON(!mapping_empty),
618 * nor even WARN_ON(!mapping_empty).
620 xa_unlock_irq(&inode
->i_data
.i_pages
);
621 BUG_ON(!list_empty(&inode
->i_data
.private_list
));
622 BUG_ON(!(inode
->i_state
& I_FREEING
));
623 BUG_ON(inode
->i_state
& I_CLEAR
);
624 BUG_ON(!list_empty(&inode
->i_wb_list
));
625 /* don't need i_lock here, no concurrent mods to i_state */
626 inode
->i_state
= I_FREEING
| I_CLEAR
;
628 EXPORT_SYMBOL(clear_inode
);
631 * Free the inode passed in, removing it from the lists it is still connected
632 * to. We remove any pages still attached to the inode and wait for any IO that
633 * is still in progress before finally destroying the inode.
635 * An inode must already be marked I_FREEING so that we avoid the inode being
636 * moved back onto lists if we race with other code that manipulates the lists
637 * (e.g. writeback_single_inode). The caller is responsible for setting this.
639 * An inode must already be removed from the LRU list before being evicted from
640 * the cache. This should occur atomically with setting the I_FREEING state
641 * flag, so no inodes here should ever be on the LRU when being evicted.
643 static void evict(struct inode
*inode
)
645 const struct super_operations
*op
= inode
->i_sb
->s_op
;
647 BUG_ON(!(inode
->i_state
& I_FREEING
));
648 BUG_ON(!list_empty(&inode
->i_lru
));
650 if (!list_empty(&inode
->i_io_list
))
651 inode_io_list_del(inode
);
653 inode_sb_list_del(inode
);
656 * Wait for flusher thread to be done with the inode so that filesystem
657 * does not start destroying it while writeback is still running. Since
658 * the inode has I_FREEING set, flusher thread won't start new work on
659 * the inode. We just have to wait for running writeback to finish.
661 inode_wait_for_writeback(inode
);
663 if (op
->evict_inode
) {
664 op
->evict_inode(inode
);
666 truncate_inode_pages_final(&inode
->i_data
);
669 if (S_ISCHR(inode
->i_mode
) && inode
->i_cdev
)
672 remove_inode_hash(inode
);
674 spin_lock(&inode
->i_lock
);
675 wake_up_bit(&inode
->i_state
, __I_NEW
);
676 BUG_ON(inode
->i_state
!= (I_FREEING
| I_CLEAR
));
677 spin_unlock(&inode
->i_lock
);
679 destroy_inode(inode
);
683 * dispose_list - dispose of the contents of a local list
684 * @head: the head of the list to free
686 * Dispose-list gets a local list with local inodes in it, so it doesn't
687 * need to worry about list corruption and SMP locks.
689 static void dispose_list(struct list_head
*head
)
691 while (!list_empty(head
)) {
694 inode
= list_first_entry(head
, struct inode
, i_lru
);
695 list_del_init(&inode
->i_lru
);
703 * evict_inodes - evict all evictable inodes for a superblock
704 * @sb: superblock to operate on
706 * Make sure that no inodes with zero refcount are retained. This is
707 * called by superblock shutdown after having SB_ACTIVE flag removed,
708 * so any inode reaching zero refcount during or after that call will
709 * be immediately evicted.
711 void evict_inodes(struct super_block
*sb
)
713 struct inode
*inode
, *next
;
717 spin_lock(&sb
->s_inode_list_lock
);
718 list_for_each_entry_safe(inode
, next
, &sb
->s_inodes
, i_sb_list
) {
719 if (atomic_read(&inode
->i_count
))
722 spin_lock(&inode
->i_lock
);
723 if (inode
->i_state
& (I_NEW
| I_FREEING
| I_WILL_FREE
)) {
724 spin_unlock(&inode
->i_lock
);
728 inode
->i_state
|= I_FREEING
;
729 inode_lru_list_del(inode
);
730 spin_unlock(&inode
->i_lock
);
731 list_add(&inode
->i_lru
, &dispose
);
734 * We can have a ton of inodes to evict at unmount time given
735 * enough memory, check to see if we need to go to sleep for a
736 * bit so we don't livelock.
738 if (need_resched()) {
739 spin_unlock(&sb
->s_inode_list_lock
);
741 dispose_list(&dispose
);
745 spin_unlock(&sb
->s_inode_list_lock
);
747 dispose_list(&dispose
);
749 EXPORT_SYMBOL_GPL(evict_inodes
);
752 * invalidate_inodes - attempt to free all inodes on a superblock
753 * @sb: superblock to operate on
754 * @kill_dirty: flag to guide handling of dirty inodes
756 * Attempts to free all inodes for a given superblock. If there were any
757 * busy inodes return a non-zero value, else zero.
758 * If @kill_dirty is set, discard dirty inodes too, otherwise treat
761 int invalidate_inodes(struct super_block
*sb
, bool kill_dirty
)
764 struct inode
*inode
, *next
;
768 spin_lock(&sb
->s_inode_list_lock
);
769 list_for_each_entry_safe(inode
, next
, &sb
->s_inodes
, i_sb_list
) {
770 spin_lock(&inode
->i_lock
);
771 if (inode
->i_state
& (I_NEW
| I_FREEING
| I_WILL_FREE
)) {
772 spin_unlock(&inode
->i_lock
);
775 if (inode
->i_state
& I_DIRTY_ALL
&& !kill_dirty
) {
776 spin_unlock(&inode
->i_lock
);
780 if (atomic_read(&inode
->i_count
)) {
781 spin_unlock(&inode
->i_lock
);
786 inode
->i_state
|= I_FREEING
;
787 inode_lru_list_del(inode
);
788 spin_unlock(&inode
->i_lock
);
789 list_add(&inode
->i_lru
, &dispose
);
790 if (need_resched()) {
791 spin_unlock(&sb
->s_inode_list_lock
);
793 dispose_list(&dispose
);
797 spin_unlock(&sb
->s_inode_list_lock
);
799 dispose_list(&dispose
);
805 * Isolate the inode from the LRU in preparation for freeing it.
807 * If the inode has the I_REFERENCED flag set, then it means that it has been
808 * used recently - the flag is set in iput_final(). When we encounter such an
809 * inode, clear the flag and move it to the back of the LRU so it gets another
810 * pass through the LRU before it gets reclaimed. This is necessary because of
811 * the fact we are doing lazy LRU updates to minimise lock contention so the
812 * LRU does not have strict ordering. Hence we don't want to reclaim inodes
813 * with this flag set because they are the inodes that are out of order.
815 static enum lru_status
inode_lru_isolate(struct list_head
*item
,
816 struct list_lru_one
*lru
, spinlock_t
*lru_lock
, void *arg
)
818 struct list_head
*freeable
= arg
;
819 struct inode
*inode
= container_of(item
, struct inode
, i_lru
);
822 * We are inverting the lru lock/inode->i_lock here, so use a
823 * trylock. If we fail to get the lock, just skip it.
825 if (!spin_trylock(&inode
->i_lock
))
829 * Inodes can get referenced, redirtied, or repopulated while
830 * they're already on the LRU, and this can make them
831 * unreclaimable for a while. Remove them lazily here; iput,
832 * sync, or the last page cache deletion will requeue them.
834 if (atomic_read(&inode
->i_count
) ||
835 (inode
->i_state
& ~I_REFERENCED
) ||
836 !mapping_shrinkable(&inode
->i_data
)) {
837 list_lru_isolate(lru
, &inode
->i_lru
);
838 spin_unlock(&inode
->i_lock
);
839 this_cpu_dec(nr_unused
);
843 /* Recently referenced inodes get one more pass */
844 if (inode
->i_state
& I_REFERENCED
) {
845 inode
->i_state
&= ~I_REFERENCED
;
846 spin_unlock(&inode
->i_lock
);
851 * On highmem systems, mapping_shrinkable() permits dropping
852 * page cache in order to free up struct inodes: lowmem might
853 * be under pressure before the cache inside the highmem zone.
855 if (inode_has_buffers(inode
) || !mapping_empty(&inode
->i_data
)) {
857 spin_unlock(&inode
->i_lock
);
858 spin_unlock(lru_lock
);
859 if (remove_inode_buffers(inode
)) {
861 reap
= invalidate_mapping_pages(&inode
->i_data
, 0, -1);
862 if (current_is_kswapd())
863 __count_vm_events(KSWAPD_INODESTEAL
, reap
);
865 __count_vm_events(PGINODESTEAL
, reap
);
866 if (current
->reclaim_state
)
867 current
->reclaim_state
->reclaimed_slab
+= reap
;
874 WARN_ON(inode
->i_state
& I_NEW
);
875 inode
->i_state
|= I_FREEING
;
876 list_lru_isolate_move(lru
, &inode
->i_lru
, freeable
);
877 spin_unlock(&inode
->i_lock
);
879 this_cpu_dec(nr_unused
);
884 * Walk the superblock inode LRU for freeable inodes and attempt to free them.
885 * This is called from the superblock shrinker function with a number of inodes
886 * to trim from the LRU. Inodes to be freed are moved to a temporary list and
887 * then are freed outside inode_lock by dispose_list().
889 long prune_icache_sb(struct super_block
*sb
, struct shrink_control
*sc
)
894 freed
= list_lru_shrink_walk(&sb
->s_inode_lru
, sc
,
895 inode_lru_isolate
, &freeable
);
896 dispose_list(&freeable
);
900 static void __wait_on_freeing_inode(struct inode
*inode
);
902 * Called with the inode lock held.
904 static struct inode
*find_inode(struct super_block
*sb
,
905 struct hlist_head
*head
,
906 int (*test
)(struct inode
*, void *),
909 struct inode
*inode
= NULL
;
912 hlist_for_each_entry(inode
, head
, i_hash
) {
913 if (inode
->i_sb
!= sb
)
915 if (!test(inode
, data
))
917 spin_lock(&inode
->i_lock
);
918 if (inode
->i_state
& (I_FREEING
|I_WILL_FREE
)) {
919 __wait_on_freeing_inode(inode
);
922 if (unlikely(inode
->i_state
& I_CREATING
)) {
923 spin_unlock(&inode
->i_lock
);
924 return ERR_PTR(-ESTALE
);
927 spin_unlock(&inode
->i_lock
);
934 * find_inode_fast is the fast path version of find_inode, see the comment at
935 * iget_locked for details.
937 static struct inode
*find_inode_fast(struct super_block
*sb
,
938 struct hlist_head
*head
, unsigned long ino
)
940 struct inode
*inode
= NULL
;
943 hlist_for_each_entry(inode
, head
, i_hash
) {
944 if (inode
->i_ino
!= ino
)
946 if (inode
->i_sb
!= sb
)
948 spin_lock(&inode
->i_lock
);
949 if (inode
->i_state
& (I_FREEING
|I_WILL_FREE
)) {
950 __wait_on_freeing_inode(inode
);
953 if (unlikely(inode
->i_state
& I_CREATING
)) {
954 spin_unlock(&inode
->i_lock
);
955 return ERR_PTR(-ESTALE
);
958 spin_unlock(&inode
->i_lock
);
965 * Each cpu owns a range of LAST_INO_BATCH numbers.
966 * 'shared_last_ino' is dirtied only once out of LAST_INO_BATCH allocations,
967 * to renew the exhausted range.
969 * This does not significantly increase overflow rate because every CPU can
970 * consume at most LAST_INO_BATCH-1 unused inode numbers. So there is
971 * NR_CPUS*(LAST_INO_BATCH-1) wastage. At 4096 and 1024, this is ~0.1% of the
972 * 2^32 range, and is a worst-case. Even a 50% wastage would only increase
973 * overflow rate by 2x, which does not seem too significant.
975 * On a 32bit, non LFS stat() call, glibc will generate an EOVERFLOW
976 * error if st_ino won't fit in target struct field. Use 32bit counter
977 * here to attempt to avoid that.
979 #define LAST_INO_BATCH 1024
980 static DEFINE_PER_CPU(unsigned int, last_ino
);
982 unsigned int get_next_ino(void)
984 unsigned int *p
= &get_cpu_var(last_ino
);
985 unsigned int res
= *p
;
988 if (unlikely((res
& (LAST_INO_BATCH
-1)) == 0)) {
989 static atomic_t shared_last_ino
;
990 int next
= atomic_add_return(LAST_INO_BATCH
, &shared_last_ino
);
992 res
= next
- LAST_INO_BATCH
;
997 /* get_next_ino should not provide a 0 inode number */
1001 put_cpu_var(last_ino
);
1004 EXPORT_SYMBOL(get_next_ino
);
1007 * new_inode_pseudo - obtain an inode
1010 * Allocates a new inode for given superblock.
1011 * Inode wont be chained in superblock s_inodes list
1013 * - fs can't be unmount
1014 * - quotas, fsnotify, writeback can't work
1016 struct inode
*new_inode_pseudo(struct super_block
*sb
)
1018 struct inode
*inode
= alloc_inode(sb
);
1021 spin_lock(&inode
->i_lock
);
1023 spin_unlock(&inode
->i_lock
);
1024 INIT_LIST_HEAD(&inode
->i_sb_list
);
1030 * new_inode - obtain an inode
1033 * Allocates a new inode for given superblock. The default gfp_mask
1034 * for allocations related to inode->i_mapping is GFP_HIGHUSER_MOVABLE.
1035 * If HIGHMEM pages are unsuitable or it is known that pages allocated
1036 * for the page cache are not reclaimable or migratable,
1037 * mapping_set_gfp_mask() must be called with suitable flags on the
1038 * newly created inode's mapping
1041 struct inode
*new_inode(struct super_block
*sb
)
1043 struct inode
*inode
;
1045 spin_lock_prefetch(&sb
->s_inode_list_lock
);
1047 inode
= new_inode_pseudo(sb
);
1049 inode_sb_list_add(inode
);
1052 EXPORT_SYMBOL(new_inode
);
1054 #ifdef CONFIG_DEBUG_LOCK_ALLOC
1055 void lockdep_annotate_inode_mutex_key(struct inode
*inode
)
1057 if (S_ISDIR(inode
->i_mode
)) {
1058 struct file_system_type
*type
= inode
->i_sb
->s_type
;
1060 /* Set new key only if filesystem hasn't already changed it */
1061 if (lockdep_match_class(&inode
->i_rwsem
, &type
->i_mutex_key
)) {
1063 * ensure nobody is actually holding i_mutex
1065 // mutex_destroy(&inode->i_mutex);
1066 init_rwsem(&inode
->i_rwsem
);
1067 lockdep_set_class(&inode
->i_rwsem
,
1068 &type
->i_mutex_dir_key
);
1072 EXPORT_SYMBOL(lockdep_annotate_inode_mutex_key
);
1076 * unlock_new_inode - clear the I_NEW state and wake up any waiters
1077 * @inode: new inode to unlock
1079 * Called when the inode is fully initialised to clear the new state of the
1080 * inode and wake up anyone waiting for the inode to finish initialisation.
1082 void unlock_new_inode(struct inode
*inode
)
1084 lockdep_annotate_inode_mutex_key(inode
);
1085 spin_lock(&inode
->i_lock
);
1086 WARN_ON(!(inode
->i_state
& I_NEW
));
1087 inode
->i_state
&= ~I_NEW
& ~I_CREATING
;
1089 wake_up_bit(&inode
->i_state
, __I_NEW
);
1090 spin_unlock(&inode
->i_lock
);
1092 EXPORT_SYMBOL(unlock_new_inode
);
1094 void discard_new_inode(struct inode
*inode
)
1096 lockdep_annotate_inode_mutex_key(inode
);
1097 spin_lock(&inode
->i_lock
);
1098 WARN_ON(!(inode
->i_state
& I_NEW
));
1099 inode
->i_state
&= ~I_NEW
;
1101 wake_up_bit(&inode
->i_state
, __I_NEW
);
1102 spin_unlock(&inode
->i_lock
);
1105 EXPORT_SYMBOL(discard_new_inode
);
1108 * lock_two_nondirectories - take two i_mutexes on non-directory objects
1110 * Lock any non-NULL argument that is not a directory.
1111 * Zero, one or two objects may be locked by this function.
1113 * @inode1: first inode to lock
1114 * @inode2: second inode to lock
1116 void lock_two_nondirectories(struct inode
*inode1
, struct inode
*inode2
)
1118 if (inode1
> inode2
)
1119 swap(inode1
, inode2
);
1121 if (inode1
&& !S_ISDIR(inode1
->i_mode
))
1123 if (inode2
&& !S_ISDIR(inode2
->i_mode
) && inode2
!= inode1
)
1124 inode_lock_nested(inode2
, I_MUTEX_NONDIR2
);
1126 EXPORT_SYMBOL(lock_two_nondirectories
);
1129 * unlock_two_nondirectories - release locks from lock_two_nondirectories()
1130 * @inode1: first inode to unlock
1131 * @inode2: second inode to unlock
1133 void unlock_two_nondirectories(struct inode
*inode1
, struct inode
*inode2
)
1135 if (inode1
&& !S_ISDIR(inode1
->i_mode
))
1136 inode_unlock(inode1
);
1137 if (inode2
&& !S_ISDIR(inode2
->i_mode
) && inode2
!= inode1
)
1138 inode_unlock(inode2
);
1140 EXPORT_SYMBOL(unlock_two_nondirectories
);
1143 * inode_insert5 - obtain an inode from a mounted file system
1144 * @inode: pre-allocated inode to use for insert to cache
1145 * @hashval: hash value (usually inode number) to get
1146 * @test: callback used for comparisons between inodes
1147 * @set: callback used to initialize a new struct inode
1148 * @data: opaque data pointer to pass to @test and @set
1150 * Search for the inode specified by @hashval and @data in the inode cache,
1151 * and if present it is return it with an increased reference count. This is
1152 * a variant of iget5_locked() for callers that don't want to fail on memory
1153 * allocation of inode.
1155 * If the inode is not in cache, insert the pre-allocated inode to cache and
1156 * return it locked, hashed, and with the I_NEW flag set. The file system gets
1157 * to fill it in before unlocking it via unlock_new_inode().
1159 * Note both @test and @set are called with the inode_hash_lock held, so can't
1162 struct inode
*inode_insert5(struct inode
*inode
, unsigned long hashval
,
1163 int (*test
)(struct inode
*, void *),
1164 int (*set
)(struct inode
*, void *), void *data
)
1166 struct hlist_head
*head
= inode_hashtable
+ hash(inode
->i_sb
, hashval
);
1168 bool creating
= inode
->i_state
& I_CREATING
;
1171 spin_lock(&inode_hash_lock
);
1172 old
= find_inode(inode
->i_sb
, head
, test
, data
);
1173 if (unlikely(old
)) {
1175 * Uhhuh, somebody else created the same inode under us.
1176 * Use the old inode instead of the preallocated one.
1178 spin_unlock(&inode_hash_lock
);
1182 if (unlikely(inode_unhashed(old
))) {
1189 if (set
&& unlikely(set(inode
, data
))) {
1195 * Return the locked inode with I_NEW set, the
1196 * caller is responsible for filling in the contents
1198 spin_lock(&inode
->i_lock
);
1199 inode
->i_state
|= I_NEW
;
1200 hlist_add_head_rcu(&inode
->i_hash
, head
);
1201 spin_unlock(&inode
->i_lock
);
1203 inode_sb_list_add(inode
);
1205 spin_unlock(&inode_hash_lock
);
1209 EXPORT_SYMBOL(inode_insert5
);
1212 * iget5_locked - obtain an inode from a mounted file system
1213 * @sb: super block of file system
1214 * @hashval: hash value (usually inode number) to get
1215 * @test: callback used for comparisons between inodes
1216 * @set: callback used to initialize a new struct inode
1217 * @data: opaque data pointer to pass to @test and @set
1219 * Search for the inode specified by @hashval and @data in the inode cache,
1220 * and if present it is return it with an increased reference count. This is
1221 * a generalized version of iget_locked() for file systems where the inode
1222 * number is not sufficient for unique identification of an inode.
1224 * If the inode is not in cache, allocate a new inode and return it locked,
1225 * hashed, and with the I_NEW flag set. The file system gets to fill it in
1226 * before unlocking it via unlock_new_inode().
1228 * Note both @test and @set are called with the inode_hash_lock held, so can't
1231 struct inode
*iget5_locked(struct super_block
*sb
, unsigned long hashval
,
1232 int (*test
)(struct inode
*, void *),
1233 int (*set
)(struct inode
*, void *), void *data
)
1235 struct inode
*inode
= ilookup5(sb
, hashval
, test
, data
);
1238 struct inode
*new = alloc_inode(sb
);
1242 inode
= inode_insert5(new, hashval
, test
, set
, data
);
1243 if (unlikely(inode
!= new))
1249 EXPORT_SYMBOL(iget5_locked
);
1252 * iget_locked - obtain an inode from a mounted file system
1253 * @sb: super block of file system
1254 * @ino: inode number to get
1256 * Search for the inode specified by @ino in the inode cache and if present
1257 * return it with an increased reference count. This is for file systems
1258 * where the inode number is sufficient for unique identification of an inode.
1260 * If the inode is not in cache, allocate a new inode and return it locked,
1261 * hashed, and with the I_NEW flag set. The file system gets to fill it in
1262 * before unlocking it via unlock_new_inode().
1264 struct inode
*iget_locked(struct super_block
*sb
, unsigned long ino
)
1266 struct hlist_head
*head
= inode_hashtable
+ hash(sb
, ino
);
1267 struct inode
*inode
;
1269 spin_lock(&inode_hash_lock
);
1270 inode
= find_inode_fast(sb
, head
, ino
);
1271 spin_unlock(&inode_hash_lock
);
1275 wait_on_inode(inode
);
1276 if (unlikely(inode_unhashed(inode
))) {
1283 inode
= alloc_inode(sb
);
1287 spin_lock(&inode_hash_lock
);
1288 /* We released the lock, so.. */
1289 old
= find_inode_fast(sb
, head
, ino
);
1292 spin_lock(&inode
->i_lock
);
1293 inode
->i_state
= I_NEW
;
1294 hlist_add_head_rcu(&inode
->i_hash
, head
);
1295 spin_unlock(&inode
->i_lock
);
1296 inode_sb_list_add(inode
);
1297 spin_unlock(&inode_hash_lock
);
1299 /* Return the locked inode with I_NEW set, the
1300 * caller is responsible for filling in the contents
1306 * Uhhuh, somebody else created the same inode under
1307 * us. Use the old inode instead of the one we just
1310 spin_unlock(&inode_hash_lock
);
1311 destroy_inode(inode
);
1315 wait_on_inode(inode
);
1316 if (unlikely(inode_unhashed(inode
))) {
1323 EXPORT_SYMBOL(iget_locked
);
1326 * search the inode cache for a matching inode number.
1327 * If we find one, then the inode number we are trying to
1328 * allocate is not unique and so we should not use it.
1330 * Returns 1 if the inode number is unique, 0 if it is not.
1332 static int test_inode_iunique(struct super_block
*sb
, unsigned long ino
)
1334 struct hlist_head
*b
= inode_hashtable
+ hash(sb
, ino
);
1335 struct inode
*inode
;
1337 hlist_for_each_entry_rcu(inode
, b
, i_hash
) {
1338 if (inode
->i_ino
== ino
&& inode
->i_sb
== sb
)
1345 * iunique - get a unique inode number
1347 * @max_reserved: highest reserved inode number
1349 * Obtain an inode number that is unique on the system for a given
1350 * superblock. This is used by file systems that have no natural
1351 * permanent inode numbering system. An inode number is returned that
1352 * is higher than the reserved limit but unique.
1355 * With a large number of inodes live on the file system this function
1356 * currently becomes quite slow.
1358 ino_t
iunique(struct super_block
*sb
, ino_t max_reserved
)
1361 * On a 32bit, non LFS stat() call, glibc will generate an EOVERFLOW
1362 * error if st_ino won't fit in target struct field. Use 32bit counter
1363 * here to attempt to avoid that.
1365 static DEFINE_SPINLOCK(iunique_lock
);
1366 static unsigned int counter
;
1370 spin_lock(&iunique_lock
);
1372 if (counter
<= max_reserved
)
1373 counter
= max_reserved
+ 1;
1375 } while (!test_inode_iunique(sb
, res
));
1376 spin_unlock(&iunique_lock
);
1381 EXPORT_SYMBOL(iunique
);
1383 struct inode
*igrab(struct inode
*inode
)
1385 spin_lock(&inode
->i_lock
);
1386 if (!(inode
->i_state
& (I_FREEING
|I_WILL_FREE
))) {
1388 spin_unlock(&inode
->i_lock
);
1390 spin_unlock(&inode
->i_lock
);
1392 * Handle the case where s_op->clear_inode is not been
1393 * called yet, and somebody is calling igrab
1394 * while the inode is getting freed.
1400 EXPORT_SYMBOL(igrab
);
1403 * ilookup5_nowait - search for an inode in the inode cache
1404 * @sb: super block of file system to search
1405 * @hashval: hash value (usually inode number) to search for
1406 * @test: callback used for comparisons between inodes
1407 * @data: opaque data pointer to pass to @test
1409 * Search for the inode specified by @hashval and @data in the inode cache.
1410 * If the inode is in the cache, the inode is returned with an incremented
1413 * Note: I_NEW is not waited upon so you have to be very careful what you do
1414 * with the returned inode. You probably should be using ilookup5() instead.
1416 * Note2: @test is called with the inode_hash_lock held, so can't sleep.
1418 struct inode
*ilookup5_nowait(struct super_block
*sb
, unsigned long hashval
,
1419 int (*test
)(struct inode
*, void *), void *data
)
1421 struct hlist_head
*head
= inode_hashtable
+ hash(sb
, hashval
);
1422 struct inode
*inode
;
1424 spin_lock(&inode_hash_lock
);
1425 inode
= find_inode(sb
, head
, test
, data
);
1426 spin_unlock(&inode_hash_lock
);
1428 return IS_ERR(inode
) ? NULL
: inode
;
1430 EXPORT_SYMBOL(ilookup5_nowait
);
1433 * ilookup5 - search for an inode in the inode cache
1434 * @sb: super block of file system to search
1435 * @hashval: hash value (usually inode number) to search for
1436 * @test: callback used for comparisons between inodes
1437 * @data: opaque data pointer to pass to @test
1439 * Search for the inode specified by @hashval and @data in the inode cache,
1440 * and if the inode is in the cache, return the inode with an incremented
1441 * reference count. Waits on I_NEW before returning the inode.
1442 * returned with an incremented reference count.
1444 * This is a generalized version of ilookup() for file systems where the
1445 * inode number is not sufficient for unique identification of an inode.
1447 * Note: @test is called with the inode_hash_lock held, so can't sleep.
1449 struct inode
*ilookup5(struct super_block
*sb
, unsigned long hashval
,
1450 int (*test
)(struct inode
*, void *), void *data
)
1452 struct inode
*inode
;
1454 inode
= ilookup5_nowait(sb
, hashval
, test
, data
);
1456 wait_on_inode(inode
);
1457 if (unlikely(inode_unhashed(inode
))) {
1464 EXPORT_SYMBOL(ilookup5
);
1467 * ilookup - search for an inode in the inode cache
1468 * @sb: super block of file system to search
1469 * @ino: inode number to search for
1471 * Search for the inode @ino in the inode cache, and if the inode is in the
1472 * cache, the inode is returned with an incremented reference count.
1474 struct inode
*ilookup(struct super_block
*sb
, unsigned long ino
)
1476 struct hlist_head
*head
= inode_hashtable
+ hash(sb
, ino
);
1477 struct inode
*inode
;
1479 spin_lock(&inode_hash_lock
);
1480 inode
= find_inode_fast(sb
, head
, ino
);
1481 spin_unlock(&inode_hash_lock
);
1486 wait_on_inode(inode
);
1487 if (unlikely(inode_unhashed(inode
))) {
1494 EXPORT_SYMBOL(ilookup
);
1497 * find_inode_nowait - find an inode in the inode cache
1498 * @sb: super block of file system to search
1499 * @hashval: hash value (usually inode number) to search for
1500 * @match: callback used for comparisons between inodes
1501 * @data: opaque data pointer to pass to @match
1503 * Search for the inode specified by @hashval and @data in the inode
1504 * cache, where the helper function @match will return 0 if the inode
1505 * does not match, 1 if the inode does match, and -1 if the search
1506 * should be stopped. The @match function must be responsible for
1507 * taking the i_lock spin_lock and checking i_state for an inode being
1508 * freed or being initialized, and incrementing the reference count
1509 * before returning 1. It also must not sleep, since it is called with
1510 * the inode_hash_lock spinlock held.
1512 * This is a even more generalized version of ilookup5() when the
1513 * function must never block --- find_inode() can block in
1514 * __wait_on_freeing_inode() --- or when the caller can not increment
1515 * the reference count because the resulting iput() might cause an
1516 * inode eviction. The tradeoff is that the @match funtion must be
1517 * very carefully implemented.
1519 struct inode
*find_inode_nowait(struct super_block
*sb
,
1520 unsigned long hashval
,
1521 int (*match
)(struct inode
*, unsigned long,
1525 struct hlist_head
*head
= inode_hashtable
+ hash(sb
, hashval
);
1526 struct inode
*inode
, *ret_inode
= NULL
;
1529 spin_lock(&inode_hash_lock
);
1530 hlist_for_each_entry(inode
, head
, i_hash
) {
1531 if (inode
->i_sb
!= sb
)
1533 mval
= match(inode
, hashval
, data
);
1541 spin_unlock(&inode_hash_lock
);
1544 EXPORT_SYMBOL(find_inode_nowait
);
1547 * find_inode_rcu - find an inode in the inode cache
1548 * @sb: Super block of file system to search
1549 * @hashval: Key to hash
1550 * @test: Function to test match on an inode
1551 * @data: Data for test function
1553 * Search for the inode specified by @hashval and @data in the inode cache,
1554 * where the helper function @test will return 0 if the inode does not match
1555 * and 1 if it does. The @test function must be responsible for taking the
1556 * i_lock spin_lock and checking i_state for an inode being freed or being
1559 * If successful, this will return the inode for which the @test function
1560 * returned 1 and NULL otherwise.
1562 * The @test function is not permitted to take a ref on any inode presented.
1563 * It is also not permitted to sleep.
1565 * The caller must hold the RCU read lock.
1567 struct inode
*find_inode_rcu(struct super_block
*sb
, unsigned long hashval
,
1568 int (*test
)(struct inode
*, void *), void *data
)
1570 struct hlist_head
*head
= inode_hashtable
+ hash(sb
, hashval
);
1571 struct inode
*inode
;
1573 RCU_LOCKDEP_WARN(!rcu_read_lock_held(),
1574 "suspicious find_inode_rcu() usage");
1576 hlist_for_each_entry_rcu(inode
, head
, i_hash
) {
1577 if (inode
->i_sb
== sb
&&
1578 !(READ_ONCE(inode
->i_state
) & (I_FREEING
| I_WILL_FREE
)) &&
1584 EXPORT_SYMBOL(find_inode_rcu
);
1587 * find_inode_by_ino_rcu - Find an inode in the inode cache
1588 * @sb: Super block of file system to search
1589 * @ino: The inode number to match
1591 * Search for the inode specified by @hashval and @data in the inode cache,
1592 * where the helper function @test will return 0 if the inode does not match
1593 * and 1 if it does. The @test function must be responsible for taking the
1594 * i_lock spin_lock and checking i_state for an inode being freed or being
1597 * If successful, this will return the inode for which the @test function
1598 * returned 1 and NULL otherwise.
1600 * The @test function is not permitted to take a ref on any inode presented.
1601 * It is also not permitted to sleep.
1603 * The caller must hold the RCU read lock.
1605 struct inode
*find_inode_by_ino_rcu(struct super_block
*sb
,
1608 struct hlist_head
*head
= inode_hashtable
+ hash(sb
, ino
);
1609 struct inode
*inode
;
1611 RCU_LOCKDEP_WARN(!rcu_read_lock_held(),
1612 "suspicious find_inode_by_ino_rcu() usage");
1614 hlist_for_each_entry_rcu(inode
, head
, i_hash
) {
1615 if (inode
->i_ino
== ino
&&
1616 inode
->i_sb
== sb
&&
1617 !(READ_ONCE(inode
->i_state
) & (I_FREEING
| I_WILL_FREE
)))
1622 EXPORT_SYMBOL(find_inode_by_ino_rcu
);
1624 int insert_inode_locked(struct inode
*inode
)
1626 struct super_block
*sb
= inode
->i_sb
;
1627 ino_t ino
= inode
->i_ino
;
1628 struct hlist_head
*head
= inode_hashtable
+ hash(sb
, ino
);
1631 struct inode
*old
= NULL
;
1632 spin_lock(&inode_hash_lock
);
1633 hlist_for_each_entry(old
, head
, i_hash
) {
1634 if (old
->i_ino
!= ino
)
1636 if (old
->i_sb
!= sb
)
1638 spin_lock(&old
->i_lock
);
1639 if (old
->i_state
& (I_FREEING
|I_WILL_FREE
)) {
1640 spin_unlock(&old
->i_lock
);
1646 spin_lock(&inode
->i_lock
);
1647 inode
->i_state
|= I_NEW
| I_CREATING
;
1648 hlist_add_head_rcu(&inode
->i_hash
, head
);
1649 spin_unlock(&inode
->i_lock
);
1650 spin_unlock(&inode_hash_lock
);
1653 if (unlikely(old
->i_state
& I_CREATING
)) {
1654 spin_unlock(&old
->i_lock
);
1655 spin_unlock(&inode_hash_lock
);
1659 spin_unlock(&old
->i_lock
);
1660 spin_unlock(&inode_hash_lock
);
1662 if (unlikely(!inode_unhashed(old
))) {
1669 EXPORT_SYMBOL(insert_inode_locked
);
1671 int insert_inode_locked4(struct inode
*inode
, unsigned long hashval
,
1672 int (*test
)(struct inode
*, void *), void *data
)
1676 inode
->i_state
|= I_CREATING
;
1677 old
= inode_insert5(inode
, hashval
, test
, NULL
, data
);
1685 EXPORT_SYMBOL(insert_inode_locked4
);
1688 int generic_delete_inode(struct inode
*inode
)
1692 EXPORT_SYMBOL(generic_delete_inode
);
1695 * Called when we're dropping the last reference
1698 * Call the FS "drop_inode()" function, defaulting to
1699 * the legacy UNIX filesystem behaviour. If it tells
1700 * us to evict inode, do so. Otherwise, retain inode
1701 * in cache if fs is alive, sync and evict if fs is
1704 static void iput_final(struct inode
*inode
)
1706 struct super_block
*sb
= inode
->i_sb
;
1707 const struct super_operations
*op
= inode
->i_sb
->s_op
;
1708 unsigned long state
;
1711 WARN_ON(inode
->i_state
& I_NEW
);
1714 drop
= op
->drop_inode(inode
);
1716 drop
= generic_drop_inode(inode
);
1719 !(inode
->i_state
& I_DONTCACHE
) &&
1720 (sb
->s_flags
& SB_ACTIVE
)) {
1721 __inode_add_lru(inode
, true);
1722 spin_unlock(&inode
->i_lock
);
1726 state
= inode
->i_state
;
1728 WRITE_ONCE(inode
->i_state
, state
| I_WILL_FREE
);
1729 spin_unlock(&inode
->i_lock
);
1731 write_inode_now(inode
, 1);
1733 spin_lock(&inode
->i_lock
);
1734 state
= inode
->i_state
;
1735 WARN_ON(state
& I_NEW
);
1736 state
&= ~I_WILL_FREE
;
1739 WRITE_ONCE(inode
->i_state
, state
| I_FREEING
);
1740 if (!list_empty(&inode
->i_lru
))
1741 inode_lru_list_del(inode
);
1742 spin_unlock(&inode
->i_lock
);
1748 * iput - put an inode
1749 * @inode: inode to put
1751 * Puts an inode, dropping its usage count. If the inode use count hits
1752 * zero, the inode is then freed and may also be destroyed.
1754 * Consequently, iput() can sleep.
1756 void iput(struct inode
*inode
)
1760 BUG_ON(inode
->i_state
& I_CLEAR
);
1762 if (atomic_dec_and_lock(&inode
->i_count
, &inode
->i_lock
)) {
1763 if (inode
->i_nlink
&& (inode
->i_state
& I_DIRTY_TIME
)) {
1764 atomic_inc(&inode
->i_count
);
1765 spin_unlock(&inode
->i_lock
);
1766 trace_writeback_lazytime_iput(inode
);
1767 mark_inode_dirty_sync(inode
);
1773 EXPORT_SYMBOL(iput
);
1777 * bmap - find a block number in a file
1778 * @inode: inode owning the block number being requested
1779 * @block: pointer containing the block to find
1781 * Replaces the value in ``*block`` with the block number on the device holding
1782 * corresponding to the requested block number in the file.
1783 * That is, asked for block 4 of inode 1 the function will replace the
1784 * 4 in ``*block``, with disk block relative to the disk start that holds that
1785 * block of the file.
1787 * Returns -EINVAL in case of error, 0 otherwise. If mapping falls into a
1788 * hole, returns 0 and ``*block`` is also set to 0.
1790 int bmap(struct inode
*inode
, sector_t
*block
)
1792 if (!inode
->i_mapping
->a_ops
->bmap
)
1795 *block
= inode
->i_mapping
->a_ops
->bmap(inode
->i_mapping
, *block
);
1798 EXPORT_SYMBOL(bmap
);
1802 * With relative atime, only update atime if the previous atime is
1803 * earlier than either the ctime or mtime or if at least a day has
1804 * passed since the last atime update.
1806 static int relatime_need_update(struct vfsmount
*mnt
, struct inode
*inode
,
1807 struct timespec64 now
)
1810 if (!(mnt
->mnt_flags
& MNT_RELATIME
))
1813 * Is mtime younger than atime? If yes, update atime:
1815 if (timespec64_compare(&inode
->i_mtime
, &inode
->i_atime
) >= 0)
1818 * Is ctime younger than atime? If yes, update atime:
1820 if (timespec64_compare(&inode
->i_ctime
, &inode
->i_atime
) >= 0)
1824 * Is the previous atime value older than a day? If yes,
1827 if ((long)(now
.tv_sec
- inode
->i_atime
.tv_sec
) >= 24*60*60)
1830 * Good, we can skip the atime update:
1835 int generic_update_time(struct inode
*inode
, struct timespec64
*time
, int flags
)
1837 int dirty_flags
= 0;
1839 if (flags
& (S_ATIME
| S_CTIME
| S_MTIME
)) {
1840 if (flags
& S_ATIME
)
1841 inode
->i_atime
= *time
;
1842 if (flags
& S_CTIME
)
1843 inode
->i_ctime
= *time
;
1844 if (flags
& S_MTIME
)
1845 inode
->i_mtime
= *time
;
1847 if (inode
->i_sb
->s_flags
& SB_LAZYTIME
)
1848 dirty_flags
|= I_DIRTY_TIME
;
1850 dirty_flags
|= I_DIRTY_SYNC
;
1853 if ((flags
& S_VERSION
) && inode_maybe_inc_iversion(inode
, false))
1854 dirty_flags
|= I_DIRTY_SYNC
;
1856 __mark_inode_dirty(inode
, dirty_flags
);
1859 EXPORT_SYMBOL(generic_update_time
);
1862 * This does the actual work of updating an inodes time or version. Must have
1863 * had called mnt_want_write() before calling this.
1865 int inode_update_time(struct inode
*inode
, struct timespec64
*time
, int flags
)
1867 if (inode
->i_op
->update_time
)
1868 return inode
->i_op
->update_time(inode
, time
, flags
);
1869 return generic_update_time(inode
, time
, flags
);
1871 EXPORT_SYMBOL(inode_update_time
);
1874 * atime_needs_update - update the access time
1875 * @path: the &struct path to update
1876 * @inode: inode to update
1878 * Update the accessed time on an inode and mark it for writeback.
1879 * This function automatically handles read only file systems and media,
1880 * as well as the "noatime" flag and inode specific "noatime" markers.
1882 bool atime_needs_update(const struct path
*path
, struct inode
*inode
)
1884 struct vfsmount
*mnt
= path
->mnt
;
1885 struct timespec64 now
;
1887 if (inode
->i_flags
& S_NOATIME
)
1890 /* Atime updates will likely cause i_uid and i_gid to be written
1891 * back improprely if their true value is unknown to the vfs.
1893 if (HAS_UNMAPPED_ID(mnt_user_ns(mnt
), inode
))
1896 if (IS_NOATIME(inode
))
1898 if ((inode
->i_sb
->s_flags
& SB_NODIRATIME
) && S_ISDIR(inode
->i_mode
))
1901 if (mnt
->mnt_flags
& MNT_NOATIME
)
1903 if ((mnt
->mnt_flags
& MNT_NODIRATIME
) && S_ISDIR(inode
->i_mode
))
1906 now
= current_time(inode
);
1908 if (!relatime_need_update(mnt
, inode
, now
))
1911 if (timespec64_equal(&inode
->i_atime
, &now
))
1917 void touch_atime(const struct path
*path
)
1919 struct vfsmount
*mnt
= path
->mnt
;
1920 struct inode
*inode
= d_inode(path
->dentry
);
1921 struct timespec64 now
;
1923 if (!atime_needs_update(path
, inode
))
1926 if (!sb_start_write_trylock(inode
->i_sb
))
1929 if (__mnt_want_write(mnt
) != 0)
1932 * File systems can error out when updating inodes if they need to
1933 * allocate new space to modify an inode (such is the case for
1934 * Btrfs), but since we touch atime while walking down the path we
1935 * really don't care if we failed to update the atime of the file,
1936 * so just ignore the return value.
1937 * We may also fail on filesystems that have the ability to make parts
1938 * of the fs read only, e.g. subvolumes in Btrfs.
1940 now
= current_time(inode
);
1941 inode_update_time(inode
, &now
, S_ATIME
);
1942 __mnt_drop_write(mnt
);
1944 sb_end_write(inode
->i_sb
);
1946 EXPORT_SYMBOL(touch_atime
);
1949 * The logic we want is
1951 * if suid or (sgid and xgrp)
1954 int should_remove_suid(struct dentry
*dentry
)
1956 umode_t mode
= d_inode(dentry
)->i_mode
;
1959 /* suid always must be killed */
1960 if (unlikely(mode
& S_ISUID
))
1961 kill
= ATTR_KILL_SUID
;
1964 * sgid without any exec bits is just a mandatory locking mark; leave
1965 * it alone. If some exec bits are set, it's a real sgid; kill it.
1967 if (unlikely((mode
& S_ISGID
) && (mode
& S_IXGRP
)))
1968 kill
|= ATTR_KILL_SGID
;
1970 if (unlikely(kill
&& !capable(CAP_FSETID
) && S_ISREG(mode
)))
1975 EXPORT_SYMBOL(should_remove_suid
);
1978 * Return mask of changes for notify_change() that need to be done as a
1979 * response to write or truncate. Return 0 if nothing has to be changed.
1980 * Negative value on error (change should be denied).
1982 int dentry_needs_remove_privs(struct dentry
*dentry
)
1984 struct inode
*inode
= d_inode(dentry
);
1988 if (IS_NOSEC(inode
))
1991 mask
= should_remove_suid(dentry
);
1992 ret
= security_inode_need_killpriv(dentry
);
1996 mask
|= ATTR_KILL_PRIV
;
2000 static int __remove_privs(struct user_namespace
*mnt_userns
,
2001 struct dentry
*dentry
, int kill
)
2003 struct iattr newattrs
;
2005 newattrs
.ia_valid
= ATTR_FORCE
| kill
;
2007 * Note we call this on write, so notify_change will not
2008 * encounter any conflicting delegations:
2010 return notify_change(mnt_userns
, dentry
, &newattrs
, NULL
);
2014 * Remove special file priviledges (suid, capabilities) when file is written
2017 int file_remove_privs(struct file
*file
)
2019 struct dentry
*dentry
= file_dentry(file
);
2020 struct inode
*inode
= file_inode(file
);
2025 * Fast path for nothing security related.
2026 * As well for non-regular files, e.g. blkdev inodes.
2027 * For example, blkdev_write_iter() might get here
2028 * trying to remove privs which it is not allowed to.
2030 if (IS_NOSEC(inode
) || !S_ISREG(inode
->i_mode
))
2033 kill
= dentry_needs_remove_privs(dentry
);
2037 error
= __remove_privs(file_mnt_user_ns(file
), dentry
, kill
);
2039 inode_has_no_xattr(inode
);
2043 EXPORT_SYMBOL(file_remove_privs
);
2046 * file_update_time - update mtime and ctime time
2047 * @file: file accessed
2049 * Update the mtime and ctime members of an inode and mark the inode
2050 * for writeback. Note that this function is meant exclusively for
2051 * usage in the file write path of filesystems, and filesystems may
2052 * choose to explicitly ignore update via this function with the
2053 * S_NOCMTIME inode flag, e.g. for network filesystem where these
2054 * timestamps are handled by the server. This can return an error for
2055 * file systems who need to allocate space in order to update an inode.
2058 int file_update_time(struct file
*file
)
2060 struct inode
*inode
= file_inode(file
);
2061 struct timespec64 now
;
2065 /* First try to exhaust all avenues to not sync */
2066 if (IS_NOCMTIME(inode
))
2069 now
= current_time(inode
);
2070 if (!timespec64_equal(&inode
->i_mtime
, &now
))
2073 if (!timespec64_equal(&inode
->i_ctime
, &now
))
2076 if (IS_I_VERSION(inode
) && inode_iversion_need_inc(inode
))
2077 sync_it
|= S_VERSION
;
2082 /* Finally allowed to write? Takes lock. */
2083 if (__mnt_want_write_file(file
))
2086 ret
= inode_update_time(inode
, &now
, sync_it
);
2087 __mnt_drop_write_file(file
);
2091 EXPORT_SYMBOL(file_update_time
);
2093 /* Caller must hold the file's inode lock */
2094 int file_modified(struct file
*file
)
2099 * Clear the security bits if the process is not being run by root.
2100 * This keeps people from modifying setuid and setgid binaries.
2102 err
= file_remove_privs(file
);
2106 if (unlikely(file
->f_mode
& FMODE_NOCMTIME
))
2109 return file_update_time(file
);
2111 EXPORT_SYMBOL(file_modified
);
2113 int inode_needs_sync(struct inode
*inode
)
2117 if (S_ISDIR(inode
->i_mode
) && IS_DIRSYNC(inode
))
2121 EXPORT_SYMBOL(inode_needs_sync
);
2124 * If we try to find an inode in the inode hash while it is being
2125 * deleted, we have to wait until the filesystem completes its
2126 * deletion before reporting that it isn't found. This function waits
2127 * until the deletion _might_ have completed. Callers are responsible
2128 * to recheck inode state.
2130 * It doesn't matter if I_NEW is not set initially, a call to
2131 * wake_up_bit(&inode->i_state, __I_NEW) after removing from the hash list
2134 static void __wait_on_freeing_inode(struct inode
*inode
)
2136 wait_queue_head_t
*wq
;
2137 DEFINE_WAIT_BIT(wait
, &inode
->i_state
, __I_NEW
);
2138 wq
= bit_waitqueue(&inode
->i_state
, __I_NEW
);
2139 prepare_to_wait(wq
, &wait
.wq_entry
, TASK_UNINTERRUPTIBLE
);
2140 spin_unlock(&inode
->i_lock
);
2141 spin_unlock(&inode_hash_lock
);
2143 finish_wait(wq
, &wait
.wq_entry
);
2144 spin_lock(&inode_hash_lock
);
2147 static __initdata
unsigned long ihash_entries
;
2148 static int __init
set_ihash_entries(char *str
)
2152 ihash_entries
= simple_strtoul(str
, &str
, 0);
2155 __setup("ihash_entries=", set_ihash_entries
);
2158 * Initialize the waitqueues and inode hash table.
2160 void __init
inode_init_early(void)
2162 /* If hashes are distributed across NUMA nodes, defer
2163 * hash allocation until vmalloc space is available.
2169 alloc_large_system_hash("Inode-cache",
2170 sizeof(struct hlist_head
),
2173 HASH_EARLY
| HASH_ZERO
,
2180 void __init
inode_init(void)
2182 /* inode slab cache */
2183 inode_cachep
= kmem_cache_create("inode_cache",
2184 sizeof(struct inode
),
2186 (SLAB_RECLAIM_ACCOUNT
|SLAB_PANIC
|
2187 SLAB_MEM_SPREAD
|SLAB_ACCOUNT
),
2190 /* Hash may have been set up in inode_init_early */
2195 alloc_large_system_hash("Inode-cache",
2196 sizeof(struct hlist_head
),
2206 void init_special_inode(struct inode
*inode
, umode_t mode
, dev_t rdev
)
2208 inode
->i_mode
= mode
;
2209 if (S_ISCHR(mode
)) {
2210 inode
->i_fop
= &def_chr_fops
;
2211 inode
->i_rdev
= rdev
;
2212 } else if (S_ISBLK(mode
)) {
2213 inode
->i_fop
= &def_blk_fops
;
2214 inode
->i_rdev
= rdev
;
2215 } else if (S_ISFIFO(mode
))
2216 inode
->i_fop
= &pipefifo_fops
;
2217 else if (S_ISSOCK(mode
))
2218 ; /* leave it no_open_fops */
2220 printk(KERN_DEBUG
"init_special_inode: bogus i_mode (%o) for"
2221 " inode %s:%lu\n", mode
, inode
->i_sb
->s_id
,
2224 EXPORT_SYMBOL(init_special_inode
);
2227 * inode_init_owner - Init uid,gid,mode for new inode according to posix standards
2228 * @mnt_userns: User namespace of the mount the inode was created from
2230 * @dir: Directory inode
2231 * @mode: mode of the new inode
2233 * If the inode has been created through an idmapped mount the user namespace of
2234 * the vfsmount must be passed through @mnt_userns. This function will then take
2235 * care to map the inode according to @mnt_userns before checking permissions
2236 * and initializing i_uid and i_gid. On non-idmapped mounts or if permission
2237 * checking is to be performed on the raw inode simply passs init_user_ns.
2239 void inode_init_owner(struct user_namespace
*mnt_userns
, struct inode
*inode
,
2240 const struct inode
*dir
, umode_t mode
)
2242 inode_fsuid_set(inode
, mnt_userns
);
2243 if (dir
&& dir
->i_mode
& S_ISGID
) {
2244 inode
->i_gid
= dir
->i_gid
;
2246 /* Directories are special, and always inherit S_ISGID */
2249 else if ((mode
& (S_ISGID
| S_IXGRP
)) == (S_ISGID
| S_IXGRP
) &&
2250 !in_group_p(i_gid_into_mnt(mnt_userns
, dir
)) &&
2251 !capable_wrt_inode_uidgid(mnt_userns
, dir
, CAP_FSETID
))
2254 inode_fsgid_set(inode
, mnt_userns
);
2255 inode
->i_mode
= mode
;
2257 EXPORT_SYMBOL(inode_init_owner
);
2260 * inode_owner_or_capable - check current task permissions to inode
2261 * @mnt_userns: user namespace of the mount the inode was found from
2262 * @inode: inode being checked
2264 * Return true if current either has CAP_FOWNER in a namespace with the
2265 * inode owner uid mapped, or owns the file.
2267 * If the inode has been found through an idmapped mount the user namespace of
2268 * the vfsmount must be passed through @mnt_userns. This function will then take
2269 * care to map the inode according to @mnt_userns before checking permissions.
2270 * On non-idmapped mounts or if permission checking is to be performed on the
2271 * raw inode simply passs init_user_ns.
2273 bool inode_owner_or_capable(struct user_namespace
*mnt_userns
,
2274 const struct inode
*inode
)
2277 struct user_namespace
*ns
;
2279 i_uid
= i_uid_into_mnt(mnt_userns
, inode
);
2280 if (uid_eq(current_fsuid(), i_uid
))
2283 ns
= current_user_ns();
2284 if (kuid_has_mapping(ns
, i_uid
) && ns_capable(ns
, CAP_FOWNER
))
2288 EXPORT_SYMBOL(inode_owner_or_capable
);
2291 * Direct i/o helper functions
2293 static void __inode_dio_wait(struct inode
*inode
)
2295 wait_queue_head_t
*wq
= bit_waitqueue(&inode
->i_state
, __I_DIO_WAKEUP
);
2296 DEFINE_WAIT_BIT(q
, &inode
->i_state
, __I_DIO_WAKEUP
);
2299 prepare_to_wait(wq
, &q
.wq_entry
, TASK_UNINTERRUPTIBLE
);
2300 if (atomic_read(&inode
->i_dio_count
))
2302 } while (atomic_read(&inode
->i_dio_count
));
2303 finish_wait(wq
, &q
.wq_entry
);
2307 * inode_dio_wait - wait for outstanding DIO requests to finish
2308 * @inode: inode to wait for
2310 * Waits for all pending direct I/O requests to finish so that we can
2311 * proceed with a truncate or equivalent operation.
2313 * Must be called under a lock that serializes taking new references
2314 * to i_dio_count, usually by inode->i_mutex.
2316 void inode_dio_wait(struct inode
*inode
)
2318 if (atomic_read(&inode
->i_dio_count
))
2319 __inode_dio_wait(inode
);
2321 EXPORT_SYMBOL(inode_dio_wait
);
2324 * inode_set_flags - atomically set some inode flags
2326 * Note: the caller should be holding i_mutex, or else be sure that
2327 * they have exclusive access to the inode structure (i.e., while the
2328 * inode is being instantiated). The reason for the cmpxchg() loop
2329 * --- which wouldn't be necessary if all code paths which modify
2330 * i_flags actually followed this rule, is that there is at least one
2331 * code path which doesn't today so we use cmpxchg() out of an abundance
2334 * In the long run, i_mutex is overkill, and we should probably look
2335 * at using the i_lock spinlock to protect i_flags, and then make sure
2336 * it is so documented in include/linux/fs.h and that all code follows
2337 * the locking convention!!
2339 void inode_set_flags(struct inode
*inode
, unsigned int flags
,
2342 WARN_ON_ONCE(flags
& ~mask
);
2343 set_mask_bits(&inode
->i_flags
, mask
, flags
);
2345 EXPORT_SYMBOL(inode_set_flags
);
2347 void inode_nohighmem(struct inode
*inode
)
2349 mapping_set_gfp_mask(inode
->i_mapping
, GFP_USER
);
2351 EXPORT_SYMBOL(inode_nohighmem
);
2354 * timestamp_truncate - Truncate timespec to a granularity
2356 * @inode: inode being updated
2358 * Truncate a timespec to the granularity supported by the fs
2359 * containing the inode. Always rounds down. gran must
2360 * not be 0 nor greater than a second (NSEC_PER_SEC, or 10^9 ns).
2362 struct timespec64
timestamp_truncate(struct timespec64 t
, struct inode
*inode
)
2364 struct super_block
*sb
= inode
->i_sb
;
2365 unsigned int gran
= sb
->s_time_gran
;
2367 t
.tv_sec
= clamp(t
.tv_sec
, sb
->s_time_min
, sb
->s_time_max
);
2368 if (unlikely(t
.tv_sec
== sb
->s_time_max
|| t
.tv_sec
== sb
->s_time_min
))
2371 /* Avoid division in the common cases 1 ns and 1 s. */
2374 else if (gran
== NSEC_PER_SEC
)
2376 else if (gran
> 1 && gran
< NSEC_PER_SEC
)
2377 t
.tv_nsec
-= t
.tv_nsec
% gran
;
2379 WARN(1, "invalid file time granularity: %u", gran
);
2382 EXPORT_SYMBOL(timestamp_truncate
);
2385 * current_time - Return FS time
2388 * Return the current time truncated to the time granularity supported by
2391 * Note that inode and inode->sb cannot be NULL.
2392 * Otherwise, the function warns and returns time without truncation.
2394 struct timespec64
current_time(struct inode
*inode
)
2396 struct timespec64 now
;
2398 ktime_get_coarse_real_ts64(&now
);
2400 if (unlikely(!inode
->i_sb
)) {
2401 WARN(1, "current_time() called with uninitialized super_block in the inode");
2405 return timestamp_truncate(now
, inode
);
2407 EXPORT_SYMBOL(current_time
);