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