kernfs.h

  1/* SPDX-License-Identifier: GPL-2.0-only */
  2/*
  3 * kernfs.h - pseudo filesystem decoupled from vfs locking
  4 */
  5
  6#ifndef __LINUX_KERNFS_H
  7#define __LINUX_KERNFS_H
  8
  9#include <linux/err.h>
 10#include <linux/list.h>
 11#include <linux/mutex.h>
 12#include <linux/idr.h>
 13#include <linux/lockdep.h>
 14#include <linux/rbtree.h>
 15#include <linux/atomic.h>
 16#include <linux/bug.h>
 17#include <linux/types.h>
 18#include <linux/uidgid.h>
 19#include <linux/wait.h>
 20#include <linux/rwsem.h>
 21#include <linux/cache.h>
 22
 23struct file;
 24struct dentry;
 25struct iattr;
 26struct seq_file;
 27struct vm_area_struct;
 28struct vm_operations_struct;
 29struct super_block;
 30struct file_system_type;
 31struct poll_table_struct;
 32struct fs_context;
 33
 34struct kernfs_fs_context;
 35struct kernfs_open_node;
 36struct kernfs_iattrs;
 37
 38/*
 39 * NR_KERNFS_LOCK_BITS determines size (NR_KERNFS_LOCKS) of hash
 40 * table of locks.
 41 * Having a small hash table would impact scalability, since
 42 * more and more kernfs_node objects will end up using same lock
 43 * and having a very large hash table would waste memory.
 44 *
 45 * At the moment size of hash table of locks is being set based on
 46 * the number of CPUs as follows:
 47 *
 48 * NR_CPU      NR_KERNFS_LOCK_BITS      NR_KERNFS_LOCKS
 49 *   1                  1                       2
 50 *  2-3                 2                       4
 51 *  4-7                 4                       16
 52 *  8-15                6                       64
 53 *  16-31               8                       256
 54 *  32 and more         10                      1024
 55 *
 56 * The above relation between NR_CPU and number of locks is based
 57 * on some internal experimentation which involved booting qemu
 58 * with different values of smp, performing some sysfs operations
 59 * on all CPUs and observing how increase in number of locks impacts
 60 * completion time of these sysfs operations on each CPU.
 61 */
 62#ifdef CONFIG_SMP
 63#define NR_KERNFS_LOCK_BITS (2 * (ilog2(NR_CPUS < 32 ? NR_CPUS : 32)))
 64#else
 65#define NR_KERNFS_LOCK_BITS     1
 66#endif
 67
 68#define NR_KERNFS_LOCKS     (1 << NR_KERNFS_LOCK_BITS)
 69
 70/*
 71 * There's one kernfs_open_file for each open file and one kernfs_open_node
 72 * for each kernfs_node with one or more open files.
 73 *
 74 * filp->private_data points to seq_file whose ->private points to
 75 * kernfs_open_file.
 76 *
 77 * kernfs_open_files are chained at kernfs_open_node->files, which is
 78 * protected by kernfs_global_locks.open_file_mutex[i].
 79 *
 80 * To reduce possible contention in sysfs access, arising due to single
 81 * locks, use an array of locks (e.g. open_file_mutex) and use kernfs_node
 82 * object address as hash keys to get the index of these locks.
 83 *
 84 * Hashed mutexes are safe to use here because operations using these don't
 85 * rely on global exclusion.
 86 *
 87 * In future we intend to replace other global locks with hashed ones as well.
 88 * kernfs_global_locks acts as a holder for all such hash tables.
 89 */
 90struct kernfs_global_locks {
 91	struct mutex open_file_mutex[NR_KERNFS_LOCKS];
 92};
 93
 94enum kernfs_node_type {
 95	KERNFS_DIR		= 0x0001,
 96	KERNFS_FILE		= 0x0002,
 97	KERNFS_LINK		= 0x0004,
 98};
 99
100#define KERNFS_TYPE_MASK		0x000f
101#define KERNFS_FLAG_MASK		~KERNFS_TYPE_MASK
102#define KERNFS_MAX_USER_XATTRS		128
103#define KERNFS_USER_XATTR_SIZE_LIMIT	(128 << 10)
104
105enum kernfs_node_flag {
106	KERNFS_ACTIVATED	= 0x0010,
107	KERNFS_NS		= 0x0020,
108	KERNFS_HAS_SEQ_SHOW	= 0x0040,
109	KERNFS_HAS_MMAP		= 0x0080,
110	KERNFS_LOCKDEP		= 0x0100,
111	KERNFS_HIDDEN		= 0x0200,
112	KERNFS_SUICIDAL		= 0x0400,
113	KERNFS_SUICIDED		= 0x0800,
114	KERNFS_EMPTY_DIR	= 0x1000,
115	KERNFS_HAS_RELEASE	= 0x2000,
116	KERNFS_REMOVING		= 0x4000,
117};
118
119/* @flags for kernfs_create_root() */
120enum kernfs_root_flag {
121	/*
122	 * kernfs_nodes are created in the deactivated state and invisible.
123	 * They require explicit kernfs_activate() to become visible.  This
124	 * can be used to make related nodes become visible atomically
125	 * after all nodes are created successfully.
126	 */
127	KERNFS_ROOT_CREATE_DEACTIVATED		= 0x0001,
128
129	/*
130	 * For regular files, if the opener has CAP_DAC_OVERRIDE, open(2)
131	 * succeeds regardless of the RW permissions.  sysfs had an extra
132	 * layer of enforcement where open(2) fails with -EACCES regardless
133	 * of CAP_DAC_OVERRIDE if the permission doesn't have the
134	 * respective read or write access at all (none of S_IRUGO or
135	 * S_IWUGO) or the respective operation isn't implemented.  The
136	 * following flag enables that behavior.
137	 */
138	KERNFS_ROOT_EXTRA_OPEN_PERM_CHECK	= 0x0002,
139
140	/*
141	 * The filesystem supports exportfs operation, so userspace can use
142	 * fhandle to access nodes of the fs.
143	 */
144	KERNFS_ROOT_SUPPORT_EXPORTOP		= 0x0004,
145
146	/*
147	 * Support user xattrs to be written to nodes rooted at this root.
148	 */
149	KERNFS_ROOT_SUPPORT_USER_XATTR		= 0x0008,
150
151	/*
152	 * Renames must not change the parent node.
153	 */
154	KERNFS_ROOT_INVARIANT_PARENT		= 0x0010,
155};
156
157/* type-specific structures for kernfs_node union members */
158struct kernfs_elem_dir {
159	unsigned long		subdirs;
160	/* children rbtree starts here and goes through kn->rb */
161	struct rb_root		children;
162
163	/*
164	 * The kernfs hierarchy this directory belongs to.  This fits
165	 * better directly in kernfs_node but is here to save space.
166	 */
167	struct kernfs_root	*root;
168	/*
169	 * Monotonic revision counter, used to identify if a directory
170	 * node has changed during negative dentry revalidation.
171	 */
172	unsigned long		rev;
173};
174
175struct kernfs_elem_symlink {
176	struct kernfs_node	*target_kn;
177};
178
179struct kernfs_elem_attr {
180	const struct kernfs_ops	*ops;
181	struct kernfs_open_node __rcu	*open;
182	loff_t			size;
183	struct kernfs_node	*notify_next;	/* for kernfs_notify() */
184};
185
186/*
187 * kernfs_node - the building block of kernfs hierarchy.  Each and every
188 * kernfs node is represented by single kernfs_node.  Most fields are
189 * private to kernfs and shouldn't be accessed directly by kernfs users.
190 *
191 * As long as count reference is held, the kernfs_node itself is
192 * accessible.  Dereferencing elem or any other outer entity requires
193 * active reference.
194 */
195struct kernfs_node {
196	atomic_t		count;
197	atomic_t		active;
198#ifdef CONFIG_DEBUG_LOCK_ALLOC
199	struct lockdep_map	dep_map;
200#endif
201	/*
202	 * Use kernfs_get_parent() and kernfs_name/path() instead of
203	 * accessing the following two fields directly.  If the node is
204	 * never moved to a different parent, it is safe to access the
205	 * parent directly.
206	 */
207	struct kernfs_node	__rcu *__parent;
208	const char		__rcu *name;
209
210	struct rb_node		rb;
211
212	const void		*ns;	/* namespace tag */
213	unsigned int		hash;	/* ns + name hash */
214	unsigned short		flags;
215	umode_t			mode;
216
217	union {
218		struct kernfs_elem_dir		dir;
219		struct kernfs_elem_symlink	symlink;
220		struct kernfs_elem_attr		attr;
221	};
222
223	/*
224	 * 64bit unique ID.  On 64bit ino setups, id is the ino.  On 32bit,
225	 * the low 32bits are ino and upper generation.
226	 */
227	u64			id;
228
229	void			*priv;
230	struct kernfs_iattrs	*iattr;
231
232	struct rcu_head		rcu;
233};
234
235/*
236 * kernfs_syscall_ops may be specified on kernfs_create_root() to support
237 * syscalls.  These optional callbacks are invoked on the matching syscalls
238 * and can perform any kernfs operations which don't necessarily have to be
239 * the exact operation requested.  An active reference is held for each
240 * kernfs_node parameter.
241 */
242struct kernfs_syscall_ops {
243	int (*show_options)(struct seq_file *sf, struct kernfs_root *root);
244
245	int (*mkdir)(struct kernfs_node *parent, const char *name,
246		     umode_t mode);
247	int (*rmdir)(struct kernfs_node *kn);
248	int (*rename)(struct kernfs_node *kn, struct kernfs_node *new_parent,
249		      const char *new_name);
250	int (*show_path)(struct seq_file *sf, struct kernfs_node *kn,
251			 struct kernfs_root *root);
252};
253
254struct kernfs_node *kernfs_root_to_node(struct kernfs_root *root);
255
256struct kernfs_open_file {
257	/* published fields */
258	struct kernfs_node	*kn;
259	struct file		*file;
260	struct seq_file		*seq_file;
261	void			*priv;
262
263	/* private fields, do not use outside kernfs proper */
264	struct mutex		mutex;
265	struct mutex		prealloc_mutex;
266	int			event;
267	struct list_head	list;
268	char			*prealloc_buf;
269
270	size_t			atomic_write_len;
271	bool			mmapped:1;
272	bool			released:1;
273	const struct vm_operations_struct *vm_ops;
274};
275
276struct kernfs_ops {
277	/*
278	 * Optional open/release methods.  Both are called with
279	 * @of->seq_file populated.
280	 */
281	int (*open)(struct kernfs_open_file *of);
282	void (*release)(struct kernfs_open_file *of);
283
284	/*
285	 * Read is handled by either seq_file or raw_read().
286	 *
287	 * If seq_show() is present, seq_file path is active.  Other seq
288	 * operations are optional and if not implemented, the behavior is
289	 * equivalent to single_open().  @sf->private points to the
290	 * associated kernfs_open_file.
291	 *
292	 * read() is bounced through kernel buffer and a read larger than
293	 * PAGE_SIZE results in partial operation of PAGE_SIZE.
294	 */
295	int (*seq_show)(struct seq_file *sf, void *v);
296
297	void *(*seq_start)(struct seq_file *sf, loff_t *ppos);
298	void *(*seq_next)(struct seq_file *sf, void *v, loff_t *ppos);
299	void (*seq_stop)(struct seq_file *sf, void *v);
300
301	ssize_t (*read)(struct kernfs_open_file *of, char *buf, size_t bytes,
302			loff_t off);
303
304	/*
305	 * write() is bounced through kernel buffer.  If atomic_write_len
306	 * is not set, a write larger than PAGE_SIZE results in partial
307	 * operations of PAGE_SIZE chunks.  If atomic_write_len is set,
308	 * writes upto the specified size are executed atomically but
309	 * larger ones are rejected with -E2BIG.
310	 */
311	size_t atomic_write_len;
312	/*
313	 * "prealloc" causes a buffer to be allocated at open for
314	 * all read/write requests.  As ->seq_show uses seq_read()
315	 * which does its own allocation, it is incompatible with
316	 * ->prealloc.  Provide ->read and ->write with ->prealloc.
317	 */
318	bool prealloc;
319	ssize_t (*write)(struct kernfs_open_file *of, char *buf, size_t bytes,
320			 loff_t off);
321
322	__poll_t (*poll)(struct kernfs_open_file *of,
323			 struct poll_table_struct *pt);
324
325	int (*mmap)(struct kernfs_open_file *of, struct vm_area_struct *vma);
326	loff_t (*llseek)(struct kernfs_open_file *of, loff_t offset, int whence);
327};
328
329/*
330 * The kernfs superblock creation/mount parameter context.
331 */
332struct kernfs_fs_context {
333	struct kernfs_root	*root;		/* Root of the hierarchy being mounted */
334	void			*ns_tag;	/* Namespace tag of the mount (or NULL) */
335	unsigned long		magic;		/* File system specific magic number */
336
337	/* The following are set/used by kernfs_mount() */
338	bool			new_sb_created;	/* Set to T if we allocated a new sb */
339};
340
341#ifdef CONFIG_KERNFS
342
343static inline enum kernfs_node_type kernfs_type(struct kernfs_node *kn)
344{
345	return kn->flags & KERNFS_TYPE_MASK;
346}
347
348static inline ino_t kernfs_id_ino(u64 id)
349{
350	/* id is ino if ino_t is 64bit; otherwise, low 32bits */
351	if (sizeof(ino_t) >= sizeof(u64))
352		return id;
353	else
354		return (u32)id;
355}
356
357static inline u32 kernfs_id_gen(u64 id)
358{
359	/* gen is fixed at 1 if ino_t is 64bit; otherwise, high 32bits */
360	if (sizeof(ino_t) >= sizeof(u64))
361		return 1;
362	else
363		return id >> 32;
364}
365
366static inline ino_t kernfs_ino(struct kernfs_node *kn)
367{
368	return kernfs_id_ino(kn->id);
369}
370
371static inline ino_t kernfs_gen(struct kernfs_node *kn)
372{
373	return kernfs_id_gen(kn->id);
374}
375
376/**
377 * kernfs_enable_ns - enable namespace under a directory
378 * @kn: directory of interest, should be empty
379 *
380 * This is to be called right after @kn is created to enable namespace
381 * under it.  All children of @kn must have non-NULL namespace tags and
382 * only the ones which match the super_block's tag will be visible.
383 */
384static inline void kernfs_enable_ns(struct kernfs_node *kn)
385{
386	WARN_ON_ONCE(kernfs_type(kn) != KERNFS_DIR);
387	WARN_ON_ONCE(!RB_EMPTY_ROOT(&kn->dir.children));
388	kn->flags |= KERNFS_NS;
389}
390
391/**
392 * kernfs_ns_enabled - test whether namespace is enabled
393 * @kn: the node to test
394 *
395 * Test whether namespace filtering is enabled for the children of @ns.
396 */
397static inline bool kernfs_ns_enabled(struct kernfs_node *kn)
398{
399	return kn->flags & KERNFS_NS;
400}
401
402int kernfs_name(struct kernfs_node *kn, char *buf, size_t buflen);
403int kernfs_path_from_node(struct kernfs_node *kn_to, struct kernfs_node *kn_from,
404			  char *buf, size_t buflen);
405void pr_cont_kernfs_name(struct kernfs_node *kn);
406void pr_cont_kernfs_path(struct kernfs_node *kn);
407struct kernfs_node *kernfs_get_parent(struct kernfs_node *kn);
408struct kernfs_node *kernfs_find_and_get_ns(struct kernfs_node *parent,
409					   const char *name, const void *ns);
410struct kernfs_node *kernfs_walk_and_get_ns(struct kernfs_node *parent,
411					   const char *path, const void *ns);
412void kernfs_get(struct kernfs_node *kn);
413void kernfs_put(struct kernfs_node *kn);
414
415struct kernfs_node *kernfs_node_from_dentry(struct dentry *dentry);
416struct kernfs_root *kernfs_root_from_sb(struct super_block *sb);
417struct inode *kernfs_get_inode(struct super_block *sb, struct kernfs_node *kn);
418
419struct dentry *kernfs_node_dentry(struct kernfs_node *kn,
420				  struct super_block *sb);
421struct kernfs_root *kernfs_create_root(struct kernfs_syscall_ops *scops,
422				       unsigned int flags, void *priv);
423void kernfs_destroy_root(struct kernfs_root *root);
424unsigned int kernfs_root_flags(struct kernfs_node *kn);
425
426struct kernfs_node *kernfs_create_dir_ns(struct kernfs_node *parent,
427					 const char *name, umode_t mode,
428					 kuid_t uid, kgid_t gid,
429					 void *priv, const void *ns);
430struct kernfs_node *kernfs_create_empty_dir(struct kernfs_node *parent,
431					    const char *name);
432struct kernfs_node *__kernfs_create_file(struct kernfs_node *parent,
433					 const char *name, umode_t mode,
434					 kuid_t uid, kgid_t gid,
435					 loff_t size,
436					 const struct kernfs_ops *ops,
437					 void *priv, const void *ns,
438					 struct lock_class_key *key);
439struct kernfs_node *kernfs_create_link(struct kernfs_node *parent,
440				       const char *name,
441				       struct kernfs_node *target);
442void kernfs_activate(struct kernfs_node *kn);
443void kernfs_show(struct kernfs_node *kn, bool show);
444void kernfs_remove(struct kernfs_node *kn);
445void kernfs_break_active_protection(struct kernfs_node *kn);
446void kernfs_unbreak_active_protection(struct kernfs_node *kn);
447bool kernfs_remove_self(struct kernfs_node *kn);
448int kernfs_remove_by_name_ns(struct kernfs_node *parent, const char *name,
449			     const void *ns);
450int kernfs_rename_ns(struct kernfs_node *kn, struct kernfs_node *new_parent,
451		     const char *new_name, const void *new_ns);
452int kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr);
453__poll_t kernfs_generic_poll(struct kernfs_open_file *of,
454			     struct poll_table_struct *pt);
455void kernfs_notify(struct kernfs_node *kn);
456
457int kernfs_xattr_get(struct kernfs_node *kn, const char *name,
458		     void *value, size_t size);
459int kernfs_xattr_set(struct kernfs_node *kn, const char *name,
460		     const void *value, size_t size, int flags);
461
462const void *kernfs_super_ns(struct super_block *sb);
463int kernfs_get_tree(struct fs_context *fc);
464void kernfs_free_fs_context(struct fs_context *fc);
465void kernfs_kill_sb(struct super_block *sb);
466
467void kernfs_init(void);
468
469struct kernfs_node *kernfs_find_and_get_node_by_id(struct kernfs_root *root,
470						   u64 id);
471#else	/* CONFIG_KERNFS */
472
473static inline enum kernfs_node_type kernfs_type(struct kernfs_node *kn)
474{ return 0; }	/* whatever */
475
476static inline void kernfs_enable_ns(struct kernfs_node *kn) { }
477
478static inline bool kernfs_ns_enabled(struct kernfs_node *kn)
479{ return false; }
480
481static inline int kernfs_name(struct kernfs_node *kn, char *buf, size_t buflen)
482{ return -ENOSYS; }
483
484static inline int kernfs_path_from_node(struct kernfs_node *root_kn,
485					struct kernfs_node *kn,
486					char *buf, size_t buflen)
487{ return -ENOSYS; }
488
489static inline void pr_cont_kernfs_name(struct kernfs_node *kn) { }
490static inline void pr_cont_kernfs_path(struct kernfs_node *kn) { }
491
492static inline struct kernfs_node *kernfs_get_parent(struct kernfs_node *kn)
493{ return NULL; }
494
495static inline struct kernfs_node *
496kernfs_find_and_get_ns(struct kernfs_node *parent, const char *name,
497		       const void *ns)
498{ return NULL; }
499static inline struct kernfs_node *
500kernfs_walk_and_get_ns(struct kernfs_node *parent, const char *path,
501		       const void *ns)
502{ return NULL; }
503
504static inline void kernfs_get(struct kernfs_node *kn) { }
505static inline void kernfs_put(struct kernfs_node *kn) { }
506
507static inline struct kernfs_node *kernfs_node_from_dentry(struct dentry *dentry)
508{ return NULL; }
509
510static inline struct kernfs_root *kernfs_root_from_sb(struct super_block *sb)
511{ return NULL; }
512
513static inline struct inode *
514kernfs_get_inode(struct super_block *sb, struct kernfs_node *kn)
515{ return NULL; }
516
517static inline struct kernfs_root *
518kernfs_create_root(struct kernfs_syscall_ops *scops, unsigned int flags,
519		   void *priv)
520{ return ERR_PTR(-ENOSYS); }
521
522static inline void kernfs_destroy_root(struct kernfs_root *root) { }
523static inline unsigned int kernfs_root_flags(struct kernfs_node *kn)
524{ return 0; }
525
526static inline struct kernfs_node *
527kernfs_create_dir_ns(struct kernfs_node *parent, const char *name,
528		     umode_t mode, kuid_t uid, kgid_t gid,
529		     void *priv, const void *ns)
530{ return ERR_PTR(-ENOSYS); }
531
532static inline struct kernfs_node *
533__kernfs_create_file(struct kernfs_node *parent, const char *name,
534		     umode_t mode, kuid_t uid, kgid_t gid,
535		     loff_t size, const struct kernfs_ops *ops,
536		     void *priv, const void *ns, struct lock_class_key *key)
537{ return ERR_PTR(-ENOSYS); }
538
539static inline struct kernfs_node *
540kernfs_create_link(struct kernfs_node *parent, const char *name,
541		   struct kernfs_node *target)
542{ return ERR_PTR(-ENOSYS); }
543
544static inline void kernfs_activate(struct kernfs_node *kn) { }
545
546static inline void kernfs_remove(struct kernfs_node *kn) { }
547
548static inline bool kernfs_remove_self(struct kernfs_node *kn)
549{ return false; }
550
551static inline int kernfs_remove_by_name_ns(struct kernfs_node *kn,
552					   const char *name, const void *ns)
553{ return -ENOSYS; }
554
555static inline int kernfs_rename_ns(struct kernfs_node *kn,
556				   struct kernfs_node *new_parent,
557				   const char *new_name, const void *new_ns)
558{ return -ENOSYS; }
559
560static inline int kernfs_setattr(struct kernfs_node *kn,
561				 const struct iattr *iattr)
562{ return -ENOSYS; }
563
564static inline __poll_t kernfs_generic_poll(struct kernfs_open_file *of,
565					   struct poll_table_struct *pt)
566{ return -ENOSYS; }
567
568static inline void kernfs_notify(struct kernfs_node *kn) { }
569
570static inline int kernfs_xattr_get(struct kernfs_node *kn, const char *name,
571				   void *value, size_t size)
572{ return -ENOSYS; }
573
574static inline int kernfs_xattr_set(struct kernfs_node *kn, const char *name,
575				   const void *value, size_t size, int flags)
576{ return -ENOSYS; }
577
578static inline const void *kernfs_super_ns(struct super_block *sb)
579{ return NULL; }
580
581static inline int kernfs_get_tree(struct fs_context *fc)
582{ return -ENOSYS; }
583
584static inline void kernfs_free_fs_context(struct fs_context *fc) { }
585
586static inline void kernfs_kill_sb(struct super_block *sb) { }
587
588static inline void kernfs_init(void) { }
589
590#endif	/* CONFIG_KERNFS */
591
592/**
593 * kernfs_path - build full path of a given node
594 * @kn: kernfs_node of interest
595 * @buf: buffer to copy @kn's name into
596 * @buflen: size of @buf
597 *
598 * If @kn is NULL result will be "(null)".
599 *
600 * Returns the length of the full path.  If the full length is equal to or
601 * greater than @buflen, @buf contains the truncated path with the trailing
602 * '\0'.  On error, -errno is returned.
603 */
604static inline int kernfs_path(struct kernfs_node *kn, char *buf, size_t buflen)
605{
606	return kernfs_path_from_node(kn, NULL, buf, buflen);
607}
608
609static inline struct kernfs_node *
610kernfs_find_and_get(struct kernfs_node *kn, const char *name)
611{
612	return kernfs_find_and_get_ns(kn, name, NULL);
613}
614
615static inline struct kernfs_node *
616kernfs_walk_and_get(struct kernfs_node *kn, const char *path)
617{
618	return kernfs_walk_and_get_ns(kn, path, NULL);
619}
620
621static inline struct kernfs_node *
622kernfs_create_dir(struct kernfs_node *parent, const char *name, umode_t mode,
623		  void *priv)
624{
625	return kernfs_create_dir_ns(parent, name, mode,
626				    GLOBAL_ROOT_UID, GLOBAL_ROOT_GID,
627				    priv, NULL);
628}
629
630static inline int kernfs_remove_by_name(struct kernfs_node *parent,
631					const char *name)
632{
633	return kernfs_remove_by_name_ns(parent, name, NULL);
634}
635
636static inline int kernfs_rename(struct kernfs_node *kn,
637				struct kernfs_node *new_parent,
638				const char *new_name)
639{
640	return kernfs_rename_ns(kn, new_parent, new_name, NULL);
641}
642
643#endif	/* __LINUX_KERNFS_H */