4 * (C) 1997 Linus Torvalds
9 #include <linux/dcache.h>
10 #include <linux/init.h>
11 #include <linux/slab.h>
12 #include <linux/writeback.h>
13 #include <linux/module.h>
14 #include <linux/backing-dev.h>
15 #include <linux/wait.h>
16 #include <linux/rwsem.h>
17 #include <linux/hash.h>
18 #include <linux/swap.h>
19 #include <linux/security.h>
20 #include <linux/pagemap.h>
21 #include <linux/cdev.h>
22 #include <linux/bootmem.h>
23 #include <linux/fsnotify.h>
24 #include <linux/mount.h>
25 #include <linux/async.h>
26 #include <linux/posix_acl.h>
29 * This is needed for the following functions:
31 * - invalidate_inode_buffers
34 * FIXME: remove all knowledge of the buffer layer from this file
36 #include <linux/buffer_head.h>
39 * New inode.c implementation.
41 * This implementation has the basic premise of trying
42 * to be extremely low-overhead and SMP-safe, yet be
43 * simple enough to be "obviously correct".
48 /* inode dynamic allocation 1999, Andrea Arcangeli <andrea@suse.de> */
50 /* #define INODE_PARANOIA 1 */
51 /* #define INODE_DEBUG 1 */
54 * Inode lookup is no longer as critical as it used to be:
55 * most of the lookups are going to be through the dcache.
57 #define I_HASHBITS i_hash_shift
58 #define I_HASHMASK i_hash_mask
60 static unsigned int i_hash_mask __read_mostly
;
61 static unsigned int i_hash_shift __read_mostly
;
64 * Each inode can be on two separate lists. One is
65 * the hash list of the inode, used for lookups. The
66 * other linked list is the "type" list:
67 * "in_use" - valid inode, i_count > 0, i_nlink > 0
68 * "dirty" - as "in_use" but also dirty
69 * "unused" - valid inode, i_count = 0
71 * A "dirty" list is maintained for each super block,
72 * allowing for low-overhead inode sync() operations.
75 static LIST_HEAD(inode_unused
);
76 static struct hlist_head
*inode_hashtable __read_mostly
;
79 * A simple spinlock to protect the list manipulations.
81 * NOTE! You also have to own the lock if you change
82 * the i_state of an inode while it is in use..
84 DEFINE_SPINLOCK(inode_lock
);
87 * iprune_sem provides exclusion between the kswapd or try_to_free_pages
88 * icache shrinking path, and the umount path. Without this exclusion,
89 * by the time prune_icache calls iput for the inode whose pages it has
90 * been invalidating, or by the time it calls clear_inode & destroy_inode
91 * from its final dispose_list, the struct super_block they refer to
92 * (for inode->i_sb->s_op) may already have been freed and reused.
94 * We make this an rwsem because the fastpath is icache shrinking. In
95 * some cases a filesystem may be doing a significant amount of work in
96 * its inode reclaim code, so this should improve parallelism.
98 static DECLARE_RWSEM(iprune_sem
);
101 * Statistics gathering..
103 struct inodes_stat_t inodes_stat
;
105 static struct percpu_counter nr_inodes __cacheline_aligned_in_smp
;
106 static struct percpu_counter nr_inodes_unused __cacheline_aligned_in_smp
;
108 static struct kmem_cache
*inode_cachep __read_mostly
;
110 static inline int get_nr_inodes(void)
112 return percpu_counter_sum_positive(&nr_inodes
);
115 static inline int get_nr_inodes_unused(void)
117 return percpu_counter_sum_positive(&nr_inodes_unused
);
120 int get_nr_dirty_inodes(void)
122 int nr_dirty
= get_nr_inodes() - get_nr_inodes_unused();
123 return nr_dirty
> 0 ? nr_dirty
: 0;
128 * Handle nr_inode sysctl
131 int proc_nr_inodes(ctl_table
*table
, int write
,
132 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
134 inodes_stat
.nr_inodes
= get_nr_inodes();
135 inodes_stat
.nr_unused
= get_nr_inodes_unused();
136 return proc_dointvec(table
, write
, buffer
, lenp
, ppos
);
140 static void wake_up_inode(struct inode
*inode
)
143 * Prevent speculative execution through spin_unlock(&inode_lock);
146 wake_up_bit(&inode
->i_state
, __I_NEW
);
150 * inode_init_always - perform inode structure intialisation
151 * @sb: superblock inode belongs to
152 * @inode: inode to initialise
154 * These are initializations that need to be done on every inode
155 * allocation as the fields are not initialised by slab allocation.
157 int inode_init_always(struct super_block
*sb
, struct inode
*inode
)
159 static const struct address_space_operations empty_aops
;
160 static const struct inode_operations empty_iops
;
161 static const struct file_operations empty_fops
;
162 struct address_space
*const mapping
= &inode
->i_data
;
165 inode
->i_blkbits
= sb
->s_blocksize_bits
;
167 atomic_set(&inode
->i_count
, 1);
168 inode
->i_op
= &empty_iops
;
169 inode
->i_fop
= &empty_fops
;
173 atomic_set(&inode
->i_writecount
, 0);
177 inode
->i_generation
= 0;
179 memset(&inode
->i_dquot
, 0, sizeof(inode
->i_dquot
));
181 inode
->i_pipe
= NULL
;
182 inode
->i_bdev
= NULL
;
183 inode
->i_cdev
= NULL
;
185 inode
->dirtied_when
= 0;
187 if (security_inode_alloc(inode
))
189 spin_lock_init(&inode
->i_lock
);
190 lockdep_set_class(&inode
->i_lock
, &sb
->s_type
->i_lock_key
);
192 mutex_init(&inode
->i_mutex
);
193 lockdep_set_class(&inode
->i_mutex
, &sb
->s_type
->i_mutex_key
);
195 init_rwsem(&inode
->i_alloc_sem
);
196 lockdep_set_class(&inode
->i_alloc_sem
, &sb
->s_type
->i_alloc_sem_key
);
198 mapping
->a_ops
= &empty_aops
;
199 mapping
->host
= inode
;
201 mapping_set_gfp_mask(mapping
, GFP_HIGHUSER_MOVABLE
);
202 mapping
->assoc_mapping
= NULL
;
203 mapping
->backing_dev_info
= &default_backing_dev_info
;
204 mapping
->writeback_index
= 0;
207 * If the block_device provides a backing_dev_info for client
208 * inodes then use that. Otherwise the inode share the bdev's
212 struct backing_dev_info
*bdi
;
214 bdi
= sb
->s_bdev
->bd_inode
->i_mapping
->backing_dev_info
;
215 mapping
->backing_dev_info
= bdi
;
217 inode
->i_private
= NULL
;
218 inode
->i_mapping
= mapping
;
219 #ifdef CONFIG_FS_POSIX_ACL
220 inode
->i_acl
= inode
->i_default_acl
= ACL_NOT_CACHED
;
223 #ifdef CONFIG_FSNOTIFY
224 inode
->i_fsnotify_mask
= 0;
227 percpu_counter_inc(&nr_inodes
);
233 EXPORT_SYMBOL(inode_init_always
);
235 static struct inode
*alloc_inode(struct super_block
*sb
)
239 if (sb
->s_op
->alloc_inode
)
240 inode
= sb
->s_op
->alloc_inode(sb
);
242 inode
= kmem_cache_alloc(inode_cachep
, GFP_KERNEL
);
247 if (unlikely(inode_init_always(sb
, inode
))) {
248 if (inode
->i_sb
->s_op
->destroy_inode
)
249 inode
->i_sb
->s_op
->destroy_inode(inode
);
251 kmem_cache_free(inode_cachep
, inode
);
258 void __destroy_inode(struct inode
*inode
)
260 BUG_ON(inode_has_buffers(inode
));
261 security_inode_free(inode
);
262 fsnotify_inode_delete(inode
);
263 #ifdef CONFIG_FS_POSIX_ACL
264 if (inode
->i_acl
&& inode
->i_acl
!= ACL_NOT_CACHED
)
265 posix_acl_release(inode
->i_acl
);
266 if (inode
->i_default_acl
&& inode
->i_default_acl
!= ACL_NOT_CACHED
)
267 posix_acl_release(inode
->i_default_acl
);
269 percpu_counter_dec(&nr_inodes
);
271 EXPORT_SYMBOL(__destroy_inode
);
273 static void destroy_inode(struct inode
*inode
)
275 __destroy_inode(inode
);
276 if (inode
->i_sb
->s_op
->destroy_inode
)
277 inode
->i_sb
->s_op
->destroy_inode(inode
);
279 kmem_cache_free(inode_cachep
, (inode
));
283 * These are initializations that only need to be done
284 * once, because the fields are idempotent across use
285 * of the inode, so let the slab aware of that.
287 void inode_init_once(struct inode
*inode
)
289 memset(inode
, 0, sizeof(*inode
));
290 INIT_HLIST_NODE(&inode
->i_hash
);
291 INIT_LIST_HEAD(&inode
->i_dentry
);
292 INIT_LIST_HEAD(&inode
->i_devices
);
293 INIT_LIST_HEAD(&inode
->i_list
);
294 INIT_RADIX_TREE(&inode
->i_data
.page_tree
, GFP_ATOMIC
);
295 spin_lock_init(&inode
->i_data
.tree_lock
);
296 spin_lock_init(&inode
->i_data
.i_mmap_lock
);
297 INIT_LIST_HEAD(&inode
->i_data
.private_list
);
298 spin_lock_init(&inode
->i_data
.private_lock
);
299 INIT_RAW_PRIO_TREE_ROOT(&inode
->i_data
.i_mmap
);
300 INIT_LIST_HEAD(&inode
->i_data
.i_mmap_nonlinear
);
301 i_size_ordered_init(inode
);
302 #ifdef CONFIG_FSNOTIFY
303 INIT_HLIST_HEAD(&inode
->i_fsnotify_marks
);
306 EXPORT_SYMBOL(inode_init_once
);
308 static void init_once(void *foo
)
310 struct inode
*inode
= (struct inode
*) foo
;
312 inode_init_once(inode
);
316 * inode_lock must be held
318 void __iget(struct inode
*inode
)
320 atomic_inc(&inode
->i_count
);
324 * get additional reference to inode; caller must already hold one.
326 void ihold(struct inode
*inode
)
328 WARN_ON(atomic_inc_return(&inode
->i_count
) < 2);
330 EXPORT_SYMBOL(ihold
);
332 static void inode_lru_list_add(struct inode
*inode
)
334 if (list_empty(&inode
->i_list
)) {
335 list_add(&inode
->i_list
, &inode_unused
);
336 percpu_counter_inc(&nr_inodes_unused
);
340 static void inode_lru_list_del(struct inode
*inode
)
342 if (!list_empty(&inode
->i_list
)) {
343 list_del_init(&inode
->i_list
);
344 percpu_counter_dec(&nr_inodes_unused
);
348 static inline void __inode_sb_list_add(struct inode
*inode
)
350 list_add(&inode
->i_sb_list
, &inode
->i_sb
->s_inodes
);
354 * inode_sb_list_add - add inode to the superblock list of inodes
355 * @inode: inode to add
357 void inode_sb_list_add(struct inode
*inode
)
359 spin_lock(&inode_lock
);
360 __inode_sb_list_add(inode
);
361 spin_unlock(&inode_lock
);
363 EXPORT_SYMBOL_GPL(inode_sb_list_add
);
365 static inline void __inode_sb_list_del(struct inode
*inode
)
367 list_del_init(&inode
->i_sb_list
);
370 static unsigned long hash(struct super_block
*sb
, unsigned long hashval
)
374 tmp
= (hashval
* (unsigned long)sb
) ^ (GOLDEN_RATIO_PRIME
+ hashval
) /
376 tmp
= tmp
^ ((tmp
^ GOLDEN_RATIO_PRIME
) >> I_HASHBITS
);
377 return tmp
& I_HASHMASK
;
381 * __insert_inode_hash - hash an inode
382 * @inode: unhashed inode
383 * @hashval: unsigned long value used to locate this object in the
386 * Add an inode to the inode hash for this superblock.
388 void __insert_inode_hash(struct inode
*inode
, unsigned long hashval
)
390 struct hlist_head
*b
= inode_hashtable
+ hash(inode
->i_sb
, hashval
);
392 spin_lock(&inode_lock
);
393 hlist_add_head(&inode
->i_hash
, b
);
394 spin_unlock(&inode_lock
);
396 EXPORT_SYMBOL(__insert_inode_hash
);
399 * __remove_inode_hash - remove an inode from the hash
400 * @inode: inode to unhash
402 * Remove an inode from the superblock.
404 static void __remove_inode_hash(struct inode
*inode
)
406 hlist_del_init(&inode
->i_hash
);
410 * remove_inode_hash - remove an inode from the hash
411 * @inode: inode to unhash
413 * Remove an inode from the superblock.
415 void remove_inode_hash(struct inode
*inode
)
417 spin_lock(&inode_lock
);
418 hlist_del_init(&inode
->i_hash
);
419 spin_unlock(&inode_lock
);
421 EXPORT_SYMBOL(remove_inode_hash
);
423 void end_writeback(struct inode
*inode
)
426 BUG_ON(inode
->i_data
.nrpages
);
427 BUG_ON(!list_empty(&inode
->i_data
.private_list
));
428 BUG_ON(!(inode
->i_state
& I_FREEING
));
429 BUG_ON(inode
->i_state
& I_CLEAR
);
430 inode_sync_wait(inode
);
431 inode
->i_state
= I_FREEING
| I_CLEAR
;
433 EXPORT_SYMBOL(end_writeback
);
435 static void evict(struct inode
*inode
)
437 const struct super_operations
*op
= inode
->i_sb
->s_op
;
439 if (op
->evict_inode
) {
440 op
->evict_inode(inode
);
442 if (inode
->i_data
.nrpages
)
443 truncate_inode_pages(&inode
->i_data
, 0);
444 end_writeback(inode
);
446 if (S_ISBLK(inode
->i_mode
) && inode
->i_bdev
)
448 if (S_ISCHR(inode
->i_mode
) && inode
->i_cdev
)
453 * dispose_list - dispose of the contents of a local list
454 * @head: the head of the list to free
456 * Dispose-list gets a local list with local inodes in it, so it doesn't
457 * need to worry about list corruption and SMP locks.
459 static void dispose_list(struct list_head
*head
)
461 while (!list_empty(head
)) {
464 inode
= list_first_entry(head
, struct inode
, i_list
);
465 list_del_init(&inode
->i_list
);
469 spin_lock(&inode_lock
);
470 __remove_inode_hash(inode
);
471 __inode_sb_list_del(inode
);
472 spin_unlock(&inode_lock
);
474 wake_up_inode(inode
);
475 destroy_inode(inode
);
480 * Invalidate all inodes for a device.
482 static int invalidate_list(struct list_head
*head
, struct list_head
*dispose
)
484 struct list_head
*next
;
489 struct list_head
*tmp
= next
;
493 * We can reschedule here without worrying about the list's
494 * consistency because the per-sb list of inodes must not
495 * change during umount anymore, and because iprune_sem keeps
496 * shrink_icache_memory() away.
498 cond_resched_lock(&inode_lock
);
503 inode
= list_entry(tmp
, struct inode
, i_sb_list
);
504 if (inode
->i_state
& I_NEW
)
506 invalidate_inode_buffers(inode
);
507 if (!atomic_read(&inode
->i_count
)) {
508 list_move(&inode
->i_list
, dispose
);
509 WARN_ON(inode
->i_state
& I_NEW
);
510 inode
->i_state
|= I_FREEING
;
511 if (!(inode
->i_state
& (I_DIRTY
| I_SYNC
)))
512 percpu_counter_dec(&nr_inodes_unused
);
521 * invalidate_inodes - discard the inodes on a device
524 * Discard all of the inodes for a given superblock. If the discard
525 * fails because there are busy inodes then a non zero value is returned.
526 * If the discard is successful all the inodes have been discarded.
528 int invalidate_inodes(struct super_block
*sb
)
531 LIST_HEAD(throw_away
);
533 down_write(&iprune_sem
);
534 spin_lock(&inode_lock
);
535 fsnotify_unmount_inodes(&sb
->s_inodes
);
536 busy
= invalidate_list(&sb
->s_inodes
, &throw_away
);
537 spin_unlock(&inode_lock
);
539 dispose_list(&throw_away
);
540 up_write(&iprune_sem
);
545 static int can_unuse(struct inode
*inode
)
547 if (inode
->i_state
& ~I_REFERENCED
)
549 if (inode_has_buffers(inode
))
551 if (atomic_read(&inode
->i_count
))
553 if (inode
->i_data
.nrpages
)
559 * Scan `goal' inodes on the unused list for freeable ones. They are moved to a
560 * temporary list and then are freed outside inode_lock by dispose_list().
562 * Any inodes which are pinned purely because of attached pagecache have their
563 * pagecache removed. If the inode has metadata buffers attached to
564 * mapping->private_list then try to remove them.
566 * If the inode has the I_REFERENCED flag set, then it means that it has been
567 * used recently - the flag is set in iput_final(). When we encounter such an
568 * inode, clear the flag and move it to the back of the LRU so it gets another
569 * pass through the LRU before it gets reclaimed. This is necessary because of
570 * the fact we are doing lazy LRU updates to minimise lock contention so the
571 * LRU does not have strict ordering. Hence we don't want to reclaim inodes
572 * with this flag set because they are the inodes that are out of order.
574 static void prune_icache(int nr_to_scan
)
578 unsigned long reap
= 0;
580 down_read(&iprune_sem
);
581 spin_lock(&inode_lock
);
582 for (nr_scanned
= 0; nr_scanned
< nr_to_scan
; nr_scanned
++) {
585 if (list_empty(&inode_unused
))
588 inode
= list_entry(inode_unused
.prev
, struct inode
, i_list
);
591 * Referenced or dirty inodes are still in use. Give them
592 * another pass through the LRU as we canot reclaim them now.
594 if (atomic_read(&inode
->i_count
) ||
595 (inode
->i_state
& ~I_REFERENCED
)) {
596 list_del_init(&inode
->i_list
);
597 percpu_counter_dec(&nr_inodes_unused
);
601 /* recently referenced inodes get one more pass */
602 if (inode
->i_state
& I_REFERENCED
) {
603 list_move(&inode
->i_list
, &inode_unused
);
604 inode
->i_state
&= ~I_REFERENCED
;
607 if (inode_has_buffers(inode
) || inode
->i_data
.nrpages
) {
609 spin_unlock(&inode_lock
);
610 if (remove_inode_buffers(inode
))
611 reap
+= invalidate_mapping_pages(&inode
->i_data
,
614 spin_lock(&inode_lock
);
616 if (inode
!= list_entry(inode_unused
.next
,
617 struct inode
, i_list
))
618 continue; /* wrong inode or list_empty */
619 if (!can_unuse(inode
))
622 list_move(&inode
->i_list
, &freeable
);
623 WARN_ON(inode
->i_state
& I_NEW
);
624 inode
->i_state
|= I_FREEING
;
625 percpu_counter_dec(&nr_inodes_unused
);
627 if (current_is_kswapd())
628 __count_vm_events(KSWAPD_INODESTEAL
, reap
);
630 __count_vm_events(PGINODESTEAL
, reap
);
631 spin_unlock(&inode_lock
);
633 dispose_list(&freeable
);
634 up_read(&iprune_sem
);
638 * shrink_icache_memory() will attempt to reclaim some unused inodes. Here,
639 * "unused" means that no dentries are referring to the inodes: the files are
640 * not open and the dcache references to those inodes have already been
643 * This function is passed the number of inodes to scan, and it returns the
644 * total number of remaining possibly-reclaimable inodes.
646 static int shrink_icache_memory(struct shrinker
*shrink
, int nr
, gfp_t gfp_mask
)
650 * Nasty deadlock avoidance. We may hold various FS locks,
651 * and we don't want to recurse into the FS that called us
652 * in clear_inode() and friends..
654 if (!(gfp_mask
& __GFP_FS
))
658 return (get_nr_inodes_unused() / 100) * sysctl_vfs_cache_pressure
;
661 static struct shrinker icache_shrinker
= {
662 .shrink
= shrink_icache_memory
,
663 .seeks
= DEFAULT_SEEKS
,
666 static void __wait_on_freeing_inode(struct inode
*inode
);
668 * Called with the inode lock held.
670 static struct inode
*find_inode(struct super_block
*sb
,
671 struct hlist_head
*head
,
672 int (*test
)(struct inode
*, void *),
675 struct hlist_node
*node
;
676 struct inode
*inode
= NULL
;
679 hlist_for_each_entry(inode
, node
, head
, i_hash
) {
680 if (inode
->i_sb
!= sb
)
682 if (!test(inode
, data
))
684 if (inode
->i_state
& (I_FREEING
|I_WILL_FREE
)) {
685 __wait_on_freeing_inode(inode
);
695 * find_inode_fast is the fast path version of find_inode, see the comment at
696 * iget_locked for details.
698 static struct inode
*find_inode_fast(struct super_block
*sb
,
699 struct hlist_head
*head
, unsigned long ino
)
701 struct hlist_node
*node
;
702 struct inode
*inode
= NULL
;
705 hlist_for_each_entry(inode
, node
, head
, i_hash
) {
706 if (inode
->i_ino
!= ino
)
708 if (inode
->i_sb
!= sb
)
710 if (inode
->i_state
& (I_FREEING
|I_WILL_FREE
)) {
711 __wait_on_freeing_inode(inode
);
721 * Each cpu owns a range of LAST_INO_BATCH numbers.
722 * 'shared_last_ino' is dirtied only once out of LAST_INO_BATCH allocations,
723 * to renew the exhausted range.
725 * This does not significantly increase overflow rate because every CPU can
726 * consume at most LAST_INO_BATCH-1 unused inode numbers. So there is
727 * NR_CPUS*(LAST_INO_BATCH-1) wastage. At 4096 and 1024, this is ~0.1% of the
728 * 2^32 range, and is a worst-case. Even a 50% wastage would only increase
729 * overflow rate by 2x, which does not seem too significant.
731 * On a 32bit, non LFS stat() call, glibc will generate an EOVERFLOW
732 * error if st_ino won't fit in target struct field. Use 32bit counter
733 * here to attempt to avoid that.
735 #define LAST_INO_BATCH 1024
736 static DEFINE_PER_CPU(unsigned int, last_ino
);
738 unsigned int get_next_ino(void)
740 unsigned int *p
= &get_cpu_var(last_ino
);
741 unsigned int res
= *p
;
744 if (unlikely((res
& (LAST_INO_BATCH
-1)) == 0)) {
745 static atomic_t shared_last_ino
;
746 int next
= atomic_add_return(LAST_INO_BATCH
, &shared_last_ino
);
748 res
= next
- LAST_INO_BATCH
;
753 put_cpu_var(last_ino
);
756 EXPORT_SYMBOL(get_next_ino
);
759 * new_inode - obtain an inode
762 * Allocates a new inode for given superblock. The default gfp_mask
763 * for allocations related to inode->i_mapping is GFP_HIGHUSER_MOVABLE.
764 * If HIGHMEM pages are unsuitable or it is known that pages allocated
765 * for the page cache are not reclaimable or migratable,
766 * mapping_set_gfp_mask() must be called with suitable flags on the
767 * newly created inode's mapping
770 struct inode
*new_inode(struct super_block
*sb
)
774 spin_lock_prefetch(&inode_lock
);
776 inode
= alloc_inode(sb
);
778 spin_lock(&inode_lock
);
779 __inode_sb_list_add(inode
);
781 spin_unlock(&inode_lock
);
785 EXPORT_SYMBOL(new_inode
);
787 void unlock_new_inode(struct inode
*inode
)
789 #ifdef CONFIG_DEBUG_LOCK_ALLOC
790 if (S_ISDIR(inode
->i_mode
)) {
791 struct file_system_type
*type
= inode
->i_sb
->s_type
;
793 /* Set new key only if filesystem hasn't already changed it */
794 if (!lockdep_match_class(&inode
->i_mutex
,
795 &type
->i_mutex_key
)) {
797 * ensure nobody is actually holding i_mutex
799 mutex_destroy(&inode
->i_mutex
);
800 mutex_init(&inode
->i_mutex
);
801 lockdep_set_class(&inode
->i_mutex
,
802 &type
->i_mutex_dir_key
);
807 * This is special! We do not need the spinlock when clearing I_NEW,
808 * because we're guaranteed that nobody else tries to do anything about
809 * the state of the inode when it is locked, as we just created it (so
810 * there can be no old holders that haven't tested I_NEW).
811 * However we must emit the memory barrier so that other CPUs reliably
812 * see the clearing of I_NEW after the other inode initialisation has
816 WARN_ON(!(inode
->i_state
& I_NEW
));
817 inode
->i_state
&= ~I_NEW
;
818 wake_up_inode(inode
);
820 EXPORT_SYMBOL(unlock_new_inode
);
823 * This is called without the inode lock held.. Be careful.
825 * We no longer cache the sb_flags in i_flags - see fs.h
826 * -- rmk@arm.uk.linux.org
828 static struct inode
*get_new_inode(struct super_block
*sb
,
829 struct hlist_head
*head
,
830 int (*test
)(struct inode
*, void *),
831 int (*set
)(struct inode
*, void *),
836 inode
= alloc_inode(sb
);
840 spin_lock(&inode_lock
);
841 /* We released the lock, so.. */
842 old
= find_inode(sb
, head
, test
, data
);
844 if (set(inode
, data
))
847 hlist_add_head(&inode
->i_hash
, head
);
848 __inode_sb_list_add(inode
);
849 inode
->i_state
= I_NEW
;
850 spin_unlock(&inode_lock
);
852 /* Return the locked inode with I_NEW set, the
853 * caller is responsible for filling in the contents
859 * Uhhuh, somebody else created the same inode under
860 * us. Use the old inode instead of the one we just
863 spin_unlock(&inode_lock
);
864 destroy_inode(inode
);
866 wait_on_inode(inode
);
871 spin_unlock(&inode_lock
);
872 destroy_inode(inode
);
877 * get_new_inode_fast is the fast path version of get_new_inode, see the
878 * comment at iget_locked for details.
880 static struct inode
*get_new_inode_fast(struct super_block
*sb
,
881 struct hlist_head
*head
, unsigned long ino
)
885 inode
= alloc_inode(sb
);
889 spin_lock(&inode_lock
);
890 /* We released the lock, so.. */
891 old
= find_inode_fast(sb
, head
, ino
);
894 hlist_add_head(&inode
->i_hash
, head
);
895 __inode_sb_list_add(inode
);
896 inode
->i_state
= I_NEW
;
897 spin_unlock(&inode_lock
);
899 /* Return the locked inode with I_NEW set, the
900 * caller is responsible for filling in the contents
906 * Uhhuh, somebody else created the same inode under
907 * us. Use the old inode instead of the one we just
910 spin_unlock(&inode_lock
);
911 destroy_inode(inode
);
913 wait_on_inode(inode
);
919 * search the inode cache for a matching inode number.
920 * If we find one, then the inode number we are trying to
921 * allocate is not unique and so we should not use it.
923 * Returns 1 if the inode number is unique, 0 if it is not.
925 static int test_inode_iunique(struct super_block
*sb
, unsigned long ino
)
927 struct hlist_head
*b
= inode_hashtable
+ hash(sb
, ino
);
928 struct hlist_node
*node
;
931 hlist_for_each_entry(inode
, node
, b
, i_hash
) {
932 if (inode
->i_ino
== ino
&& inode
->i_sb
== sb
)
940 * iunique - get a unique inode number
942 * @max_reserved: highest reserved inode number
944 * Obtain an inode number that is unique on the system for a given
945 * superblock. This is used by file systems that have no natural
946 * permanent inode numbering system. An inode number is returned that
947 * is higher than the reserved limit but unique.
950 * With a large number of inodes live on the file system this function
951 * currently becomes quite slow.
953 ino_t
iunique(struct super_block
*sb
, ino_t max_reserved
)
956 * On a 32bit, non LFS stat() call, glibc will generate an EOVERFLOW
957 * error if st_ino won't fit in target struct field. Use 32bit counter
958 * here to attempt to avoid that.
960 static DEFINE_SPINLOCK(iunique_lock
);
961 static unsigned int counter
;
964 spin_lock(&inode_lock
);
965 spin_lock(&iunique_lock
);
967 if (counter
<= max_reserved
)
968 counter
= max_reserved
+ 1;
970 } while (!test_inode_iunique(sb
, res
));
971 spin_unlock(&iunique_lock
);
972 spin_unlock(&inode_lock
);
976 EXPORT_SYMBOL(iunique
);
978 struct inode
*igrab(struct inode
*inode
)
980 spin_lock(&inode_lock
);
981 if (!(inode
->i_state
& (I_FREEING
|I_WILL_FREE
)))
985 * Handle the case where s_op->clear_inode is not been
986 * called yet, and somebody is calling igrab
987 * while the inode is getting freed.
990 spin_unlock(&inode_lock
);
993 EXPORT_SYMBOL(igrab
);
996 * ifind - internal function, you want ilookup5() or iget5().
997 * @sb: super block of file system to search
998 * @head: the head of the list to search
999 * @test: callback used for comparisons between inodes
1000 * @data: opaque data pointer to pass to @test
1001 * @wait: if true wait for the inode to be unlocked, if false do not
1003 * ifind() searches for the inode specified by @data in the inode
1004 * cache. This is a generalized version of ifind_fast() for file systems where
1005 * the inode number is not sufficient for unique identification of an inode.
1007 * If the inode is in the cache, the inode is returned with an incremented
1010 * Otherwise NULL is returned.
1012 * Note, @test is called with the inode_lock held, so can't sleep.
1014 static struct inode
*ifind(struct super_block
*sb
,
1015 struct hlist_head
*head
, int (*test
)(struct inode
*, void *),
1016 void *data
, const int wait
)
1018 struct inode
*inode
;
1020 spin_lock(&inode_lock
);
1021 inode
= find_inode(sb
, head
, test
, data
);
1023 spin_unlock(&inode_lock
);
1025 wait_on_inode(inode
);
1028 spin_unlock(&inode_lock
);
1033 * ifind_fast - internal function, you want ilookup() or iget().
1034 * @sb: super block of file system to search
1035 * @head: head of the list to search
1036 * @ino: inode number to search for
1038 * ifind_fast() searches for the inode @ino in the inode cache. This is for
1039 * file systems where the inode number is sufficient for unique identification
1042 * If the inode is in the cache, the inode is returned with an incremented
1045 * Otherwise NULL is returned.
1047 static struct inode
*ifind_fast(struct super_block
*sb
,
1048 struct hlist_head
*head
, unsigned long ino
)
1050 struct inode
*inode
;
1052 spin_lock(&inode_lock
);
1053 inode
= find_inode_fast(sb
, head
, ino
);
1055 spin_unlock(&inode_lock
);
1056 wait_on_inode(inode
);
1059 spin_unlock(&inode_lock
);
1064 * ilookup5_nowait - search for an inode in the inode cache
1065 * @sb: super block of file system to search
1066 * @hashval: hash value (usually inode number) to search for
1067 * @test: callback used for comparisons between inodes
1068 * @data: opaque data pointer to pass to @test
1070 * ilookup5() uses ifind() to search for the inode specified by @hashval and
1071 * @data in the inode cache. This is a generalized version of ilookup() for
1072 * file systems where the inode number is not sufficient for unique
1073 * identification of an inode.
1075 * If the inode is in the cache, the inode is returned with an incremented
1076 * reference count. Note, the inode lock is not waited upon so you have to be
1077 * very careful what you do with the returned inode. You probably should be
1078 * using ilookup5() instead.
1080 * Otherwise NULL is returned.
1082 * Note, @test is called with the inode_lock held, so can't sleep.
1084 struct inode
*ilookup5_nowait(struct super_block
*sb
, unsigned long hashval
,
1085 int (*test
)(struct inode
*, void *), void *data
)
1087 struct hlist_head
*head
= inode_hashtable
+ hash(sb
, hashval
);
1089 return ifind(sb
, head
, test
, data
, 0);
1091 EXPORT_SYMBOL(ilookup5_nowait
);
1094 * ilookup5 - search for an inode in the inode cache
1095 * @sb: super block of file system to search
1096 * @hashval: hash value (usually inode number) to search for
1097 * @test: callback used for comparisons between inodes
1098 * @data: opaque data pointer to pass to @test
1100 * ilookup5() uses ifind() to search for the inode specified by @hashval and
1101 * @data in the inode cache. This is a generalized version of ilookup() for
1102 * file systems where the inode number is not sufficient for unique
1103 * identification of an inode.
1105 * If the inode is in the cache, the inode lock is waited upon and the inode is
1106 * returned with an incremented reference count.
1108 * Otherwise NULL is returned.
1110 * Note, @test is called with the inode_lock held, so can't sleep.
1112 struct inode
*ilookup5(struct super_block
*sb
, unsigned long hashval
,
1113 int (*test
)(struct inode
*, void *), void *data
)
1115 struct hlist_head
*head
= inode_hashtable
+ hash(sb
, hashval
);
1117 return ifind(sb
, head
, test
, data
, 1);
1119 EXPORT_SYMBOL(ilookup5
);
1122 * ilookup - search for an inode in the inode cache
1123 * @sb: super block of file system to search
1124 * @ino: inode number to search for
1126 * ilookup() uses ifind_fast() to search for the inode @ino in the inode cache.
1127 * This is for file systems where the inode number is sufficient for unique
1128 * identification of an inode.
1130 * If the inode is in the cache, the inode is returned with an incremented
1133 * Otherwise NULL is returned.
1135 struct inode
*ilookup(struct super_block
*sb
, unsigned long ino
)
1137 struct hlist_head
*head
= inode_hashtable
+ hash(sb
, ino
);
1139 return ifind_fast(sb
, head
, ino
);
1141 EXPORT_SYMBOL(ilookup
);
1144 * iget5_locked - obtain an inode from a mounted file system
1145 * @sb: super block of file system
1146 * @hashval: hash value (usually inode number) to get
1147 * @test: callback used for comparisons between inodes
1148 * @set: callback used to initialize a new struct inode
1149 * @data: opaque data pointer to pass to @test and @set
1151 * iget5_locked() uses ifind() to search for the inode specified by @hashval
1152 * and @data in the inode cache and if present it is returned with an increased
1153 * reference count. This is a generalized version of iget_locked() for file
1154 * systems where the inode number is not sufficient for unique identification
1157 * If the inode is not in cache, get_new_inode() is called to allocate a new
1158 * inode and this is returned locked, hashed, and with the I_NEW flag set. The
1159 * file system gets to fill it in before unlocking it via unlock_new_inode().
1161 * Note both @test and @set are called with the inode_lock held, so can't sleep.
1163 struct inode
*iget5_locked(struct super_block
*sb
, unsigned long hashval
,
1164 int (*test
)(struct inode
*, void *),
1165 int (*set
)(struct inode
*, void *), void *data
)
1167 struct hlist_head
*head
= inode_hashtable
+ hash(sb
, hashval
);
1168 struct inode
*inode
;
1170 inode
= ifind(sb
, head
, test
, data
, 1);
1174 * get_new_inode() will do the right thing, re-trying the search
1175 * in case it had to block at any point.
1177 return get_new_inode(sb
, head
, test
, set
, data
);
1179 EXPORT_SYMBOL(iget5_locked
);
1182 * iget_locked - obtain an inode from a mounted file system
1183 * @sb: super block of file system
1184 * @ino: inode number to get
1186 * iget_locked() uses ifind_fast() to search for the inode specified by @ino in
1187 * the inode cache and if present it is returned with an increased reference
1188 * count. This is for file systems where the inode number is sufficient for
1189 * unique identification of an inode.
1191 * If the inode is not in cache, get_new_inode_fast() is called to allocate a
1192 * new inode and this is returned locked, hashed, and with the I_NEW flag set.
1193 * The file system gets to fill it in before unlocking it via
1194 * unlock_new_inode().
1196 struct inode
*iget_locked(struct super_block
*sb
, unsigned long ino
)
1198 struct hlist_head
*head
= inode_hashtable
+ hash(sb
, ino
);
1199 struct inode
*inode
;
1201 inode
= ifind_fast(sb
, head
, ino
);
1205 * get_new_inode_fast() will do the right thing, re-trying the search
1206 * in case it had to block at any point.
1208 return get_new_inode_fast(sb
, head
, ino
);
1210 EXPORT_SYMBOL(iget_locked
);
1212 int insert_inode_locked(struct inode
*inode
)
1214 struct super_block
*sb
= inode
->i_sb
;
1215 ino_t ino
= inode
->i_ino
;
1216 struct hlist_head
*head
= inode_hashtable
+ hash(sb
, ino
);
1218 inode
->i_state
|= I_NEW
;
1220 struct hlist_node
*node
;
1221 struct inode
*old
= NULL
;
1222 spin_lock(&inode_lock
);
1223 hlist_for_each_entry(old
, node
, head
, i_hash
) {
1224 if (old
->i_ino
!= ino
)
1226 if (old
->i_sb
!= sb
)
1228 if (old
->i_state
& (I_FREEING
|I_WILL_FREE
))
1232 if (likely(!node
)) {
1233 hlist_add_head(&inode
->i_hash
, head
);
1234 spin_unlock(&inode_lock
);
1238 spin_unlock(&inode_lock
);
1240 if (unlikely(!inode_unhashed(old
))) {
1247 EXPORT_SYMBOL(insert_inode_locked
);
1249 int insert_inode_locked4(struct inode
*inode
, unsigned long hashval
,
1250 int (*test
)(struct inode
*, void *), void *data
)
1252 struct super_block
*sb
= inode
->i_sb
;
1253 struct hlist_head
*head
= inode_hashtable
+ hash(sb
, hashval
);
1255 inode
->i_state
|= I_NEW
;
1258 struct hlist_node
*node
;
1259 struct inode
*old
= NULL
;
1261 spin_lock(&inode_lock
);
1262 hlist_for_each_entry(old
, node
, head
, i_hash
) {
1263 if (old
->i_sb
!= sb
)
1265 if (!test(old
, data
))
1267 if (old
->i_state
& (I_FREEING
|I_WILL_FREE
))
1271 if (likely(!node
)) {
1272 hlist_add_head(&inode
->i_hash
, head
);
1273 spin_unlock(&inode_lock
);
1277 spin_unlock(&inode_lock
);
1279 if (unlikely(!inode_unhashed(old
))) {
1286 EXPORT_SYMBOL(insert_inode_locked4
);
1289 int generic_delete_inode(struct inode
*inode
)
1293 EXPORT_SYMBOL(generic_delete_inode
);
1296 * Normal UNIX filesystem behaviour: delete the
1297 * inode when the usage count drops to zero, and
1300 int generic_drop_inode(struct inode
*inode
)
1302 return !inode
->i_nlink
|| inode_unhashed(inode
);
1304 EXPORT_SYMBOL_GPL(generic_drop_inode
);
1307 * Called when we're dropping the last reference
1310 * Call the FS "drop_inode()" function, defaulting to
1311 * the legacy UNIX filesystem behaviour. If it tells
1312 * us to evict inode, do so. Otherwise, retain inode
1313 * in cache if fs is alive, sync and evict if fs is
1316 static void iput_final(struct inode
*inode
)
1318 struct super_block
*sb
= inode
->i_sb
;
1319 const struct super_operations
*op
= inode
->i_sb
->s_op
;
1322 if (op
&& op
->drop_inode
)
1323 drop
= op
->drop_inode(inode
);
1325 drop
= generic_drop_inode(inode
);
1328 if (sb
->s_flags
& MS_ACTIVE
) {
1329 inode
->i_state
|= I_REFERENCED
;
1330 if (!(inode
->i_state
& (I_DIRTY
|I_SYNC
))) {
1331 inode_lru_list_add(inode
);
1333 spin_unlock(&inode_lock
);
1336 WARN_ON(inode
->i_state
& I_NEW
);
1337 inode
->i_state
|= I_WILL_FREE
;
1338 spin_unlock(&inode_lock
);
1339 write_inode_now(inode
, 1);
1340 spin_lock(&inode_lock
);
1341 WARN_ON(inode
->i_state
& I_NEW
);
1342 inode
->i_state
&= ~I_WILL_FREE
;
1343 __remove_inode_hash(inode
);
1345 WARN_ON(inode
->i_state
& I_NEW
);
1346 inode
->i_state
|= I_FREEING
;
1349 * After we delete the inode from the LRU here, we avoid moving dirty
1350 * inodes back onto the LRU now because I_FREEING is set and hence
1351 * writeback_single_inode() won't move the inode around.
1353 inode_lru_list_del(inode
);
1355 __inode_sb_list_del(inode
);
1356 spin_unlock(&inode_lock
);
1358 remove_inode_hash(inode
);
1359 wake_up_inode(inode
);
1360 BUG_ON(inode
->i_state
!= (I_FREEING
| I_CLEAR
));
1361 destroy_inode(inode
);
1365 * iput - put an inode
1366 * @inode: inode to put
1368 * Puts an inode, dropping its usage count. If the inode use count hits
1369 * zero, the inode is then freed and may also be destroyed.
1371 * Consequently, iput() can sleep.
1373 void iput(struct inode
*inode
)
1376 BUG_ON(inode
->i_state
& I_CLEAR
);
1378 if (atomic_dec_and_lock(&inode
->i_count
, &inode_lock
))
1382 EXPORT_SYMBOL(iput
);
1385 * bmap - find a block number in a file
1386 * @inode: inode of file
1387 * @block: block to find
1389 * Returns the block number on the device holding the inode that
1390 * is the disk block number for the block of the file requested.
1391 * That is, asked for block 4 of inode 1 the function will return the
1392 * disk block relative to the disk start that holds that block of the
1395 sector_t
bmap(struct inode
*inode
, sector_t block
)
1398 if (inode
->i_mapping
->a_ops
->bmap
)
1399 res
= inode
->i_mapping
->a_ops
->bmap(inode
->i_mapping
, block
);
1402 EXPORT_SYMBOL(bmap
);
1405 * With relative atime, only update atime if the previous atime is
1406 * earlier than either the ctime or mtime or if at least a day has
1407 * passed since the last atime update.
1409 static int relatime_need_update(struct vfsmount
*mnt
, struct inode
*inode
,
1410 struct timespec now
)
1413 if (!(mnt
->mnt_flags
& MNT_RELATIME
))
1416 * Is mtime younger than atime? If yes, update atime:
1418 if (timespec_compare(&inode
->i_mtime
, &inode
->i_atime
) >= 0)
1421 * Is ctime younger than atime? If yes, update atime:
1423 if (timespec_compare(&inode
->i_ctime
, &inode
->i_atime
) >= 0)
1427 * Is the previous atime value older than a day? If yes,
1430 if ((long)(now
.tv_sec
- inode
->i_atime
.tv_sec
) >= 24*60*60)
1433 * Good, we can skip the atime update:
1439 * touch_atime - update the access time
1440 * @mnt: mount the inode is accessed on
1441 * @dentry: dentry accessed
1443 * Update the accessed time on an inode and mark it for writeback.
1444 * This function automatically handles read only file systems and media,
1445 * as well as the "noatime" flag and inode specific "noatime" markers.
1447 void touch_atime(struct vfsmount
*mnt
, struct dentry
*dentry
)
1449 struct inode
*inode
= dentry
->d_inode
;
1450 struct timespec now
;
1452 if (inode
->i_flags
& S_NOATIME
)
1454 if (IS_NOATIME(inode
))
1456 if ((inode
->i_sb
->s_flags
& MS_NODIRATIME
) && S_ISDIR(inode
->i_mode
))
1459 if (mnt
->mnt_flags
& MNT_NOATIME
)
1461 if ((mnt
->mnt_flags
& MNT_NODIRATIME
) && S_ISDIR(inode
->i_mode
))
1464 now
= current_fs_time(inode
->i_sb
);
1466 if (!relatime_need_update(mnt
, inode
, now
))
1469 if (timespec_equal(&inode
->i_atime
, &now
))
1472 if (mnt_want_write(mnt
))
1475 inode
->i_atime
= now
;
1476 mark_inode_dirty_sync(inode
);
1477 mnt_drop_write(mnt
);
1479 EXPORT_SYMBOL(touch_atime
);
1482 * file_update_time - update mtime and ctime time
1483 * @file: file accessed
1485 * Update the mtime and ctime members of an inode and mark the inode
1486 * for writeback. Note that this function is meant exclusively for
1487 * usage in the file write path of filesystems, and filesystems may
1488 * choose to explicitly ignore update via this function with the
1489 * S_NOCMTIME inode flag, e.g. for network filesystem where these
1490 * timestamps are handled by the server.
1493 void file_update_time(struct file
*file
)
1495 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
1496 struct timespec now
;
1497 enum { S_MTIME
= 1, S_CTIME
= 2, S_VERSION
= 4 } sync_it
= 0;
1499 /* First try to exhaust all avenues to not sync */
1500 if (IS_NOCMTIME(inode
))
1503 now
= current_fs_time(inode
->i_sb
);
1504 if (!timespec_equal(&inode
->i_mtime
, &now
))
1507 if (!timespec_equal(&inode
->i_ctime
, &now
))
1510 if (IS_I_VERSION(inode
))
1511 sync_it
|= S_VERSION
;
1516 /* Finally allowed to write? Takes lock. */
1517 if (mnt_want_write_file(file
))
1520 /* Only change inode inside the lock region */
1521 if (sync_it
& S_VERSION
)
1522 inode_inc_iversion(inode
);
1523 if (sync_it
& S_CTIME
)
1524 inode
->i_ctime
= now
;
1525 if (sync_it
& S_MTIME
)
1526 inode
->i_mtime
= now
;
1527 mark_inode_dirty_sync(inode
);
1528 mnt_drop_write(file
->f_path
.mnt
);
1530 EXPORT_SYMBOL(file_update_time
);
1532 int inode_needs_sync(struct inode
*inode
)
1536 if (S_ISDIR(inode
->i_mode
) && IS_DIRSYNC(inode
))
1540 EXPORT_SYMBOL(inode_needs_sync
);
1542 int inode_wait(void *word
)
1547 EXPORT_SYMBOL(inode_wait
);
1550 * If we try to find an inode in the inode hash while it is being
1551 * deleted, we have to wait until the filesystem completes its
1552 * deletion before reporting that it isn't found. This function waits
1553 * until the deletion _might_ have completed. Callers are responsible
1554 * to recheck inode state.
1556 * It doesn't matter if I_NEW is not set initially, a call to
1557 * wake_up_inode() after removing from the hash list will DTRT.
1559 * This is called with inode_lock held.
1561 static void __wait_on_freeing_inode(struct inode
*inode
)
1563 wait_queue_head_t
*wq
;
1564 DEFINE_WAIT_BIT(wait
, &inode
->i_state
, __I_NEW
);
1565 wq
= bit_waitqueue(&inode
->i_state
, __I_NEW
);
1566 prepare_to_wait(wq
, &wait
.wait
, TASK_UNINTERRUPTIBLE
);
1567 spin_unlock(&inode_lock
);
1569 finish_wait(wq
, &wait
.wait
);
1570 spin_lock(&inode_lock
);
1573 static __initdata
unsigned long ihash_entries
;
1574 static int __init
set_ihash_entries(char *str
)
1578 ihash_entries
= simple_strtoul(str
, &str
, 0);
1581 __setup("ihash_entries=", set_ihash_entries
);
1584 * Initialize the waitqueues and inode hash table.
1586 void __init
inode_init_early(void)
1590 /* If hashes are distributed across NUMA nodes, defer
1591 * hash allocation until vmalloc space is available.
1597 alloc_large_system_hash("Inode-cache",
1598 sizeof(struct hlist_head
),
1606 for (loop
= 0; loop
< (1 << i_hash_shift
); loop
++)
1607 INIT_HLIST_HEAD(&inode_hashtable
[loop
]);
1610 void __init
inode_init(void)
1614 /* inode slab cache */
1615 inode_cachep
= kmem_cache_create("inode_cache",
1616 sizeof(struct inode
),
1618 (SLAB_RECLAIM_ACCOUNT
|SLAB_PANIC
|
1621 register_shrinker(&icache_shrinker
);
1622 percpu_counter_init(&nr_inodes
, 0);
1623 percpu_counter_init(&nr_inodes_unused
, 0);
1625 /* Hash may have been set up in inode_init_early */
1630 alloc_large_system_hash("Inode-cache",
1631 sizeof(struct hlist_head
),
1639 for (loop
= 0; loop
< (1 << i_hash_shift
); loop
++)
1640 INIT_HLIST_HEAD(&inode_hashtable
[loop
]);
1643 void init_special_inode(struct inode
*inode
, umode_t mode
, dev_t rdev
)
1645 inode
->i_mode
= mode
;
1646 if (S_ISCHR(mode
)) {
1647 inode
->i_fop
= &def_chr_fops
;
1648 inode
->i_rdev
= rdev
;
1649 } else if (S_ISBLK(mode
)) {
1650 inode
->i_fop
= &def_blk_fops
;
1651 inode
->i_rdev
= rdev
;
1652 } else if (S_ISFIFO(mode
))
1653 inode
->i_fop
= &def_fifo_fops
;
1654 else if (S_ISSOCK(mode
))
1655 inode
->i_fop
= &bad_sock_fops
;
1657 printk(KERN_DEBUG
"init_special_inode: bogus i_mode (%o) for"
1658 " inode %s:%lu\n", mode
, inode
->i_sb
->s_id
,
1661 EXPORT_SYMBOL(init_special_inode
);
1664 * Init uid,gid,mode for new inode according to posix standards
1666 * @dir: Directory inode
1667 * @mode: mode of the new inode
1669 void inode_init_owner(struct inode
*inode
, const struct inode
*dir
,
1672 inode
->i_uid
= current_fsuid();
1673 if (dir
&& dir
->i_mode
& S_ISGID
) {
1674 inode
->i_gid
= dir
->i_gid
;
1678 inode
->i_gid
= current_fsgid();
1679 inode
->i_mode
= mode
;
1681 EXPORT_SYMBOL(inode_init_owner
);