1 // SPDX-License-Identifier: GPL-2.0
3 * inode.c - part of debugfs, a tiny little debug file system
5 * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
6 * Copyright (C) 2004 IBM Inc.
8 * debugfs is for people to use instead of /proc or /sys.
9 * See ./Documentation/core-api/kernel-api.rst for more details.
12 #include <linux/module.h>
14 #include <linux/mount.h>
15 #include <linux/pagemap.h>
16 #include <linux/init.h>
17 #include <linux/kobject.h>
18 #include <linux/namei.h>
19 #include <linux/debugfs.h>
20 #include <linux/fsnotify.h>
21 #include <linux/string.h>
22 #include <linux/seq_file.h>
23 #include <linux/parser.h>
24 #include <linux/magic.h>
25 #include <linux/slab.h>
29 #define DEBUGFS_DEFAULT_MODE 0700
31 static struct vfsmount
*debugfs_mount
;
32 static int debugfs_mount_count
;
33 static bool debugfs_registered
;
35 static struct inode
*debugfs_get_inode(struct super_block
*sb
)
37 struct inode
*inode
= new_inode(sb
);
39 inode
->i_ino
= get_next_ino();
40 inode
->i_atime
= inode
->i_mtime
=
41 inode
->i_ctime
= current_time(inode
);
46 struct debugfs_mount_opts
{
59 static const match_table_t tokens
= {
62 {Opt_mode
, "mode=%o"},
66 struct debugfs_fs_info
{
67 struct debugfs_mount_opts mount_opts
;
70 static int debugfs_parse_options(char *data
, struct debugfs_mount_opts
*opts
)
72 substring_t args
[MAX_OPT_ARGS
];
79 opts
->mode
= DEBUGFS_DEFAULT_MODE
;
81 while ((p
= strsep(&data
, ",")) != NULL
) {
85 token
= match_token(p
, tokens
, args
);
88 if (match_int(&args
[0], &option
))
90 uid
= make_kuid(current_user_ns(), option
);
96 if (match_int(&args
[0], &option
))
98 gid
= make_kgid(current_user_ns(), option
);
104 if (match_octal(&args
[0], &option
))
106 opts
->mode
= option
& S_IALLUGO
;
109 * We might like to report bad mount options here;
110 * but traditionally debugfs has ignored all mount options
118 static int debugfs_apply_options(struct super_block
*sb
)
120 struct debugfs_fs_info
*fsi
= sb
->s_fs_info
;
121 struct inode
*inode
= d_inode(sb
->s_root
);
122 struct debugfs_mount_opts
*opts
= &fsi
->mount_opts
;
124 inode
->i_mode
&= ~S_IALLUGO
;
125 inode
->i_mode
|= opts
->mode
;
127 inode
->i_uid
= opts
->uid
;
128 inode
->i_gid
= opts
->gid
;
133 static int debugfs_remount(struct super_block
*sb
, int *flags
, char *data
)
136 struct debugfs_fs_info
*fsi
= sb
->s_fs_info
;
139 err
= debugfs_parse_options(data
, &fsi
->mount_opts
);
143 debugfs_apply_options(sb
);
149 static int debugfs_show_options(struct seq_file
*m
, struct dentry
*root
)
151 struct debugfs_fs_info
*fsi
= root
->d_sb
->s_fs_info
;
152 struct debugfs_mount_opts
*opts
= &fsi
->mount_opts
;
154 if (!uid_eq(opts
->uid
, GLOBAL_ROOT_UID
))
155 seq_printf(m
, ",uid=%u",
156 from_kuid_munged(&init_user_ns
, opts
->uid
));
157 if (!gid_eq(opts
->gid
, GLOBAL_ROOT_GID
))
158 seq_printf(m
, ",gid=%u",
159 from_kgid_munged(&init_user_ns
, opts
->gid
));
160 if (opts
->mode
!= DEBUGFS_DEFAULT_MODE
)
161 seq_printf(m
, ",mode=%o", opts
->mode
);
166 static void debugfs_i_callback(struct rcu_head
*head
)
168 struct inode
*inode
= container_of(head
, struct inode
, i_rcu
);
169 if (S_ISLNK(inode
->i_mode
))
170 kfree(inode
->i_link
);
171 free_inode_nonrcu(inode
);
174 static void debugfs_destroy_inode(struct inode
*inode
)
176 call_rcu(&inode
->i_rcu
, debugfs_i_callback
);
179 static const struct super_operations debugfs_super_operations
= {
180 .statfs
= simple_statfs
,
181 .remount_fs
= debugfs_remount
,
182 .show_options
= debugfs_show_options
,
183 .destroy_inode
= debugfs_destroy_inode
,
186 static void debugfs_release_dentry(struct dentry
*dentry
)
188 void *fsd
= dentry
->d_fsdata
;
190 if (!((unsigned long)fsd
& DEBUGFS_FSDATA_IS_REAL_FOPS_BIT
))
191 kfree(dentry
->d_fsdata
);
194 static struct vfsmount
*debugfs_automount(struct path
*path
)
196 debugfs_automount_t f
;
197 f
= (debugfs_automount_t
)path
->dentry
->d_fsdata
;
198 return f(path
->dentry
, d_inode(path
->dentry
)->i_private
);
201 static const struct dentry_operations debugfs_dops
= {
202 .d_delete
= always_delete_dentry
,
203 .d_release
= debugfs_release_dentry
,
204 .d_automount
= debugfs_automount
,
207 static int debug_fill_super(struct super_block
*sb
, void *data
, int silent
)
209 static const struct tree_descr debug_files
[] = {{""}};
210 struct debugfs_fs_info
*fsi
;
213 fsi
= kzalloc(sizeof(struct debugfs_fs_info
), GFP_KERNEL
);
220 err
= debugfs_parse_options(data
, &fsi
->mount_opts
);
224 err
= simple_fill_super(sb
, DEBUGFS_MAGIC
, debug_files
);
228 sb
->s_op
= &debugfs_super_operations
;
229 sb
->s_d_op
= &debugfs_dops
;
231 debugfs_apply_options(sb
);
237 sb
->s_fs_info
= NULL
;
241 static struct dentry
*debug_mount(struct file_system_type
*fs_type
,
242 int flags
, const char *dev_name
,
245 return mount_single(fs_type
, flags
, data
, debug_fill_super
);
248 static struct file_system_type debug_fs_type
= {
249 .owner
= THIS_MODULE
,
251 .mount
= debug_mount
,
252 .kill_sb
= kill_litter_super
,
254 MODULE_ALIAS_FS("debugfs");
257 * debugfs_lookup() - look up an existing debugfs file
258 * @name: a pointer to a string containing the name of the file to look up.
259 * @parent: a pointer to the parent dentry of the file.
261 * This function will return a pointer to a dentry if it succeeds. If the file
262 * doesn't exist or an error occurs, %NULL will be returned. The returned
263 * dentry must be passed to dput() when it is no longer needed.
265 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
268 struct dentry
*debugfs_lookup(const char *name
, struct dentry
*parent
)
270 struct dentry
*dentry
;
276 parent
= debugfs_mount
->mnt_root
;
278 inode_lock(d_inode(parent
));
279 dentry
= lookup_one_len(name
, parent
, strlen(name
));
280 inode_unlock(d_inode(parent
));
284 if (!d_really_is_positive(dentry
)) {
290 EXPORT_SYMBOL_GPL(debugfs_lookup
);
292 static struct dentry
*start_creating(const char *name
, struct dentry
*parent
)
294 struct dentry
*dentry
;
297 pr_debug("debugfs: creating file '%s'\n",name
);
302 error
= simple_pin_fs(&debug_fs_type
, &debugfs_mount
,
303 &debugfs_mount_count
);
305 return ERR_PTR(error
);
307 /* If the parent is not specified, we create it in the root.
308 * We need the root dentry to do this, which is in the super
309 * block. A pointer to that is in the struct vfsmount that we
313 parent
= debugfs_mount
->mnt_root
;
315 inode_lock(d_inode(parent
));
316 dentry
= lookup_one_len(name
, parent
, strlen(name
));
317 if (!IS_ERR(dentry
) && d_really_is_positive(dentry
)) {
319 dentry
= ERR_PTR(-EEXIST
);
322 if (IS_ERR(dentry
)) {
323 inode_unlock(d_inode(parent
));
324 simple_release_fs(&debugfs_mount
, &debugfs_mount_count
);
330 static struct dentry
*failed_creating(struct dentry
*dentry
)
332 inode_unlock(d_inode(dentry
->d_parent
));
334 simple_release_fs(&debugfs_mount
, &debugfs_mount_count
);
338 static struct dentry
*end_creating(struct dentry
*dentry
)
340 inode_unlock(d_inode(dentry
->d_parent
));
344 static struct dentry
*__debugfs_create_file(const char *name
, umode_t mode
,
345 struct dentry
*parent
, void *data
,
346 const struct file_operations
*proxy_fops
,
347 const struct file_operations
*real_fops
)
349 struct dentry
*dentry
;
352 if (!(mode
& S_IFMT
))
354 BUG_ON(!S_ISREG(mode
));
355 dentry
= start_creating(name
, parent
);
360 inode
= debugfs_get_inode(dentry
->d_sb
);
361 if (unlikely(!inode
))
362 return failed_creating(dentry
);
364 inode
->i_mode
= mode
;
365 inode
->i_private
= data
;
367 inode
->i_fop
= proxy_fops
;
368 dentry
->d_fsdata
= (void *)((unsigned long)real_fops
|
369 DEBUGFS_FSDATA_IS_REAL_FOPS_BIT
);
371 d_instantiate(dentry
, inode
);
372 fsnotify_create(d_inode(dentry
->d_parent
), dentry
);
373 return end_creating(dentry
);
377 * debugfs_create_file - create a file in the debugfs filesystem
378 * @name: a pointer to a string containing the name of the file to create.
379 * @mode: the permission that the file should have.
380 * @parent: a pointer to the parent dentry for this file. This should be a
381 * directory dentry if set. If this parameter is NULL, then the
382 * file will be created in the root of the debugfs filesystem.
383 * @data: a pointer to something that the caller will want to get to later
384 * on. The inode.i_private pointer will point to this value on
386 * @fops: a pointer to a struct file_operations that should be used for
389 * This is the basic "create a file" function for debugfs. It allows for a
390 * wide range of flexibility in creating a file, or a directory (if you want
391 * to create a directory, the debugfs_create_dir() function is
392 * recommended to be used instead.)
394 * This function will return a pointer to a dentry if it succeeds. This
395 * pointer must be passed to the debugfs_remove() function when the file is
396 * to be removed (no automatic cleanup happens if your module is unloaded,
397 * you are responsible here.) If an error occurs, %NULL will be returned.
399 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
402 struct dentry
*debugfs_create_file(const char *name
, umode_t mode
,
403 struct dentry
*parent
, void *data
,
404 const struct file_operations
*fops
)
407 return __debugfs_create_file(name
, mode
, parent
, data
,
408 fops
? &debugfs_full_proxy_file_operations
:
409 &debugfs_noop_file_operations
,
412 EXPORT_SYMBOL_GPL(debugfs_create_file
);
415 * debugfs_create_file_unsafe - create a file in the debugfs filesystem
416 * @name: a pointer to a string containing the name of the file to create.
417 * @mode: the permission that the file should have.
418 * @parent: a pointer to the parent dentry for this file. This should be a
419 * directory dentry if set. If this parameter is NULL, then the
420 * file will be created in the root of the debugfs filesystem.
421 * @data: a pointer to something that the caller will want to get to later
422 * on. The inode.i_private pointer will point to this value on
424 * @fops: a pointer to a struct file_operations that should be used for
427 * debugfs_create_file_unsafe() is completely analogous to
428 * debugfs_create_file(), the only difference being that the fops
429 * handed it will not get protected against file removals by the
432 * It is your responsibility to protect your struct file_operation
433 * methods against file removals by means of debugfs_use_file_start()
434 * and debugfs_use_file_finish(). ->open() is still protected by
437 * Any struct file_operations defined by means of
438 * DEFINE_DEBUGFS_ATTRIBUTE() is protected against file removals and
439 * thus, may be used here.
441 struct dentry
*debugfs_create_file_unsafe(const char *name
, umode_t mode
,
442 struct dentry
*parent
, void *data
,
443 const struct file_operations
*fops
)
446 return __debugfs_create_file(name
, mode
, parent
, data
,
447 fops
? &debugfs_open_proxy_file_operations
:
448 &debugfs_noop_file_operations
,
451 EXPORT_SYMBOL_GPL(debugfs_create_file_unsafe
);
454 * debugfs_create_file_size - create a file in the debugfs filesystem
455 * @name: a pointer to a string containing the name of the file to create.
456 * @mode: the permission that the file should have.
457 * @parent: a pointer to the parent dentry for this file. This should be a
458 * directory dentry if set. If this parameter is NULL, then the
459 * file will be created in the root of the debugfs filesystem.
460 * @data: a pointer to something that the caller will want to get to later
461 * on. The inode.i_private pointer will point to this value on
463 * @fops: a pointer to a struct file_operations that should be used for
465 * @file_size: initial file size
467 * This is the basic "create a file" function for debugfs. It allows for a
468 * wide range of flexibility in creating a file, or a directory (if you want
469 * to create a directory, the debugfs_create_dir() function is
470 * recommended to be used instead.)
472 * This function will return a pointer to a dentry if it succeeds. This
473 * pointer must be passed to the debugfs_remove() function when the file is
474 * to be removed (no automatic cleanup happens if your module is unloaded,
475 * you are responsible here.) If an error occurs, %NULL will be returned.
477 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
480 struct dentry
*debugfs_create_file_size(const char *name
, umode_t mode
,
481 struct dentry
*parent
, void *data
,
482 const struct file_operations
*fops
,
485 struct dentry
*de
= debugfs_create_file(name
, mode
, parent
, data
, fops
);
488 d_inode(de
)->i_size
= file_size
;
491 EXPORT_SYMBOL_GPL(debugfs_create_file_size
);
494 * debugfs_create_dir - create a directory in the debugfs filesystem
495 * @name: a pointer to a string containing the name of the directory to
497 * @parent: a pointer to the parent dentry for this file. This should be a
498 * directory dentry if set. If this parameter is NULL, then the
499 * directory will be created in the root of the debugfs filesystem.
501 * This function creates a directory in debugfs with the given name.
503 * This function will return a pointer to a dentry if it succeeds. This
504 * pointer must be passed to the debugfs_remove() function when the file is
505 * to be removed (no automatic cleanup happens if your module is unloaded,
506 * you are responsible here.) If an error occurs, %NULL will be returned.
508 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
511 struct dentry
*debugfs_create_dir(const char *name
, struct dentry
*parent
)
513 struct dentry
*dentry
= start_creating(name
, parent
);
519 inode
= debugfs_get_inode(dentry
->d_sb
);
520 if (unlikely(!inode
))
521 return failed_creating(dentry
);
523 inode
->i_mode
= S_IFDIR
| S_IRWXU
| S_IRUGO
| S_IXUGO
;
524 inode
->i_op
= &simple_dir_inode_operations
;
525 inode
->i_fop
= &simple_dir_operations
;
527 /* directory inodes start off with i_nlink == 2 (for "." entry) */
529 d_instantiate(dentry
, inode
);
530 inc_nlink(d_inode(dentry
->d_parent
));
531 fsnotify_mkdir(d_inode(dentry
->d_parent
), dentry
);
532 return end_creating(dentry
);
534 EXPORT_SYMBOL_GPL(debugfs_create_dir
);
537 * debugfs_create_automount - create automount point in the debugfs filesystem
538 * @name: a pointer to a string containing the name of the file to create.
539 * @parent: a pointer to the parent dentry for this file. This should be a
540 * directory dentry if set. If this parameter is NULL, then the
541 * file will be created in the root of the debugfs filesystem.
542 * @f: function to be called when pathname resolution steps on that one.
543 * @data: opaque argument to pass to f().
545 * @f should return what ->d_automount() would.
547 struct dentry
*debugfs_create_automount(const char *name
,
548 struct dentry
*parent
,
549 debugfs_automount_t f
,
552 struct dentry
*dentry
= start_creating(name
, parent
);
558 inode
= debugfs_get_inode(dentry
->d_sb
);
559 if (unlikely(!inode
))
560 return failed_creating(dentry
);
562 make_empty_dir_inode(inode
);
563 inode
->i_flags
|= S_AUTOMOUNT
;
564 inode
->i_private
= data
;
565 dentry
->d_fsdata
= (void *)f
;
566 /* directory inodes start off with i_nlink == 2 (for "." entry) */
568 d_instantiate(dentry
, inode
);
569 inc_nlink(d_inode(dentry
->d_parent
));
570 fsnotify_mkdir(d_inode(dentry
->d_parent
), dentry
);
571 return end_creating(dentry
);
573 EXPORT_SYMBOL(debugfs_create_automount
);
576 * debugfs_create_symlink- create a symbolic link in the debugfs filesystem
577 * @name: a pointer to a string containing the name of the symbolic link to
579 * @parent: a pointer to the parent dentry for this symbolic link. This
580 * should be a directory dentry if set. If this parameter is NULL,
581 * then the symbolic link will be created in the root of the debugfs
583 * @target: a pointer to a string containing the path to the target of the
586 * This function creates a symbolic link with the given name in debugfs that
587 * links to the given target path.
589 * This function will return a pointer to a dentry if it succeeds. This
590 * pointer must be passed to the debugfs_remove() function when the symbolic
591 * link is to be removed (no automatic cleanup happens if your module is
592 * unloaded, you are responsible here.) If an error occurs, %NULL will be
595 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
598 struct dentry
*debugfs_create_symlink(const char *name
, struct dentry
*parent
,
601 struct dentry
*dentry
;
603 char *link
= kstrdup(target
, GFP_KERNEL
);
607 dentry
= start_creating(name
, parent
);
608 if (IS_ERR(dentry
)) {
613 inode
= debugfs_get_inode(dentry
->d_sb
);
614 if (unlikely(!inode
)) {
616 return failed_creating(dentry
);
618 inode
->i_mode
= S_IFLNK
| S_IRWXUGO
;
619 inode
->i_op
= &simple_symlink_inode_operations
;
620 inode
->i_link
= link
;
621 d_instantiate(dentry
, inode
);
622 return end_creating(dentry
);
624 EXPORT_SYMBOL_GPL(debugfs_create_symlink
);
626 static void __debugfs_remove_file(struct dentry
*dentry
, struct dentry
*parent
)
628 struct debugfs_fsdata
*fsd
;
630 simple_unlink(d_inode(parent
), dentry
);
634 * Paired with the closing smp_mb() implied by a successful
635 * cmpxchg() in debugfs_file_get(): either
636 * debugfs_file_get() must see a dead dentry or we must see a
637 * debugfs_fsdata instance at ->d_fsdata here (or both).
640 fsd
= READ_ONCE(dentry
->d_fsdata
);
641 if ((unsigned long)fsd
& DEBUGFS_FSDATA_IS_REAL_FOPS_BIT
)
643 if (!refcount_dec_and_test(&fsd
->active_users
))
644 wait_for_completion(&fsd
->active_users_drained
);
647 static int __debugfs_remove(struct dentry
*dentry
, struct dentry
*parent
)
651 if (simple_positive(dentry
)) {
653 if (!d_is_reg(dentry
)) {
654 if (d_is_dir(dentry
))
655 ret
= simple_rmdir(d_inode(parent
), dentry
);
657 simple_unlink(d_inode(parent
), dentry
);
661 __debugfs_remove_file(dentry
, parent
);
669 * debugfs_remove - removes a file or directory from the debugfs filesystem
670 * @dentry: a pointer to a the dentry of the file or directory to be
671 * removed. If this parameter is NULL or an error value, nothing
674 * This function removes a file or directory in debugfs that was previously
675 * created with a call to another debugfs function (like
676 * debugfs_create_file() or variants thereof.)
678 * This function is required to be called in order for the file to be
679 * removed, no automatic cleanup of files will happen when a module is
680 * removed, you are responsible here.
682 void debugfs_remove(struct dentry
*dentry
)
684 struct dentry
*parent
;
687 if (IS_ERR_OR_NULL(dentry
))
690 parent
= dentry
->d_parent
;
691 inode_lock(d_inode(parent
));
692 ret
= __debugfs_remove(dentry
, parent
);
693 inode_unlock(d_inode(parent
));
695 simple_release_fs(&debugfs_mount
, &debugfs_mount_count
);
697 EXPORT_SYMBOL_GPL(debugfs_remove
);
700 * debugfs_remove_recursive - recursively removes a directory
701 * @dentry: a pointer to a the dentry of the directory to be removed. If this
702 * parameter is NULL or an error value, nothing will be done.
704 * This function recursively removes a directory tree in debugfs that
705 * was previously created with a call to another debugfs function
706 * (like debugfs_create_file() or variants thereof.)
708 * This function is required to be called in order for the file to be
709 * removed, no automatic cleanup of files will happen when a module is
710 * removed, you are responsible here.
712 void debugfs_remove_recursive(struct dentry
*dentry
)
714 struct dentry
*child
, *parent
;
716 if (IS_ERR_OR_NULL(dentry
))
721 inode_lock(d_inode(parent
));
724 * The parent->d_subdirs is protected by the d_lock. Outside that
725 * lock, the child can be unlinked and set to be freed which can
726 * use the d_u.d_child as the rcu head and corrupt this list.
728 spin_lock(&parent
->d_lock
);
729 list_for_each_entry(child
, &parent
->d_subdirs
, d_child
) {
730 if (!simple_positive(child
))
733 /* perhaps simple_empty(child) makes more sense */
734 if (!list_empty(&child
->d_subdirs
)) {
735 spin_unlock(&parent
->d_lock
);
736 inode_unlock(d_inode(parent
));
741 spin_unlock(&parent
->d_lock
);
743 if (!__debugfs_remove(child
, parent
))
744 simple_release_fs(&debugfs_mount
, &debugfs_mount_count
);
747 * The parent->d_lock protects agaist child from unlinking
748 * from d_subdirs. When releasing the parent->d_lock we can
749 * no longer trust that the next pointer is valid.
750 * Restart the loop. We'll skip this one with the
751 * simple_positive() check.
755 spin_unlock(&parent
->d_lock
);
757 inode_unlock(d_inode(parent
));
759 parent
= parent
->d_parent
;
760 inode_lock(d_inode(parent
));
766 if (!__debugfs_remove(child
, parent
))
767 simple_release_fs(&debugfs_mount
, &debugfs_mount_count
);
768 inode_unlock(d_inode(parent
));
770 EXPORT_SYMBOL_GPL(debugfs_remove_recursive
);
773 * debugfs_rename - rename a file/directory in the debugfs filesystem
774 * @old_dir: a pointer to the parent dentry for the renamed object. This
775 * should be a directory dentry.
776 * @old_dentry: dentry of an object to be renamed.
777 * @new_dir: a pointer to the parent dentry where the object should be
778 * moved. This should be a directory dentry.
779 * @new_name: a pointer to a string containing the target name.
781 * This function renames a file/directory in debugfs. The target must not
782 * exist for rename to succeed.
784 * This function will return a pointer to old_dentry (which is updated to
785 * reflect renaming) if it succeeds. If an error occurs, %NULL will be
788 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
791 struct dentry
*debugfs_rename(struct dentry
*old_dir
, struct dentry
*old_dentry
,
792 struct dentry
*new_dir
, const char *new_name
)
795 struct dentry
*dentry
= NULL
, *trap
;
796 struct name_snapshot old_name
;
802 if (IS_ERR_OR_NULL(old_dentry
))
805 trap
= lock_rename(new_dir
, old_dir
);
806 /* Source or destination directories don't exist? */
807 if (d_really_is_negative(old_dir
) || d_really_is_negative(new_dir
))
809 /* Source does not exist, cyclic rename, or mountpoint? */
810 if (d_really_is_negative(old_dentry
) || old_dentry
== trap
||
811 d_mountpoint(old_dentry
))
813 dentry
= lookup_one_len(new_name
, new_dir
, strlen(new_name
));
814 /* Lookup failed, cyclic rename or target exists? */
815 if (IS_ERR(dentry
) || dentry
== trap
|| d_really_is_positive(dentry
))
818 take_dentry_name_snapshot(&old_name
, old_dentry
);
820 error
= simple_rename(d_inode(old_dir
), old_dentry
, d_inode(new_dir
),
823 release_dentry_name_snapshot(&old_name
);
826 d_move(old_dentry
, dentry
);
827 fsnotify_move(d_inode(old_dir
), d_inode(new_dir
), old_name
.name
,
828 d_is_dir(old_dentry
),
830 release_dentry_name_snapshot(&old_name
);
831 unlock_rename(new_dir
, old_dir
);
835 if (dentry
&& !IS_ERR(dentry
))
837 unlock_rename(new_dir
, old_dir
);
840 EXPORT_SYMBOL_GPL(debugfs_rename
);
843 * debugfs_initialized - Tells whether debugfs has been registered
845 bool debugfs_initialized(void)
847 return debugfs_registered
;
849 EXPORT_SYMBOL_GPL(debugfs_initialized
);
851 static int __init
debugfs_init(void)
855 retval
= sysfs_create_mount_point(kernel_kobj
, "debug");
859 retval
= register_filesystem(&debug_fs_type
);
861 sysfs_remove_mount_point(kernel_kobj
, "debug");
863 debugfs_registered
= true;
867 core_initcall(debugfs_init
);