xref: /linux/include/linux/sysfs.h (revision eb3289fc474f74105e0627bf508e3f9742fd3b63)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * sysfs.h - definitions for the device driver filesystem
4  *
5  * Copyright (c) 2001,2002 Patrick Mochel
6  * Copyright (c) 2004 Silicon Graphics, Inc.
7  * Copyright (c) 2007 SUSE Linux Products GmbH
8  * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
9  *
10  * Please see Documentation/filesystems/sysfs.rst for more information.
11  */
12 
13 #ifndef _SYSFS_H_
14 #define _SYSFS_H_
15 
16 #include <linux/kernfs.h>
17 #include <linux/compiler.h>
18 #include <linux/errno.h>
19 #include <linux/list.h>
20 #include <linux/lockdep.h>
21 #include <linux/kobject_ns.h>
22 #include <linux/stat.h>
23 #include <linux/atomic.h>
24 
25 struct kobject;
26 struct module;
27 struct bin_attribute;
28 enum kobj_ns_type;
29 
30 struct attribute {
31 	const char		*name;
32 	umode_t			mode;
33 #ifdef CONFIG_DEBUG_LOCK_ALLOC
34 	bool			ignore_lockdep:1;
35 	struct lock_class_key	*key;
36 	struct lock_class_key	skey;
37 #endif
38 };
39 
40 /**
41  *	sysfs_attr_init - initialize a dynamically allocated sysfs attribute
42  *	@attr: struct attribute to initialize
43  *
44  *	Initialize a dynamically allocated struct attribute so we can
45  *	make lockdep happy.  This is a new requirement for attributes
46  *	and initially this is only needed when lockdep is enabled.
47  *	Lockdep gives a nice error when your attribute is added to
48  *	sysfs if you don't have this.
49  */
50 #ifdef CONFIG_DEBUG_LOCK_ALLOC
51 #define sysfs_attr_init(attr)				\
52 do {							\
53 	static struct lock_class_key __key;		\
54 							\
55 	(attr)->key = &__key;				\
56 } while (0)
57 #else
58 #define sysfs_attr_init(attr) do {} while (0)
59 #endif
60 
61 /**
62  * struct attribute_group - data structure used to declare an attribute group.
63  * @name:	Optional: Attribute group name
64  *		If specified, the attribute group will be created in a
65  *		new subdirectory with this name. Additionally when a
66  *		group is named, @is_visible and @is_bin_visible may
67  *		return SYSFS_GROUP_INVISIBLE to control visibility of
68  *		the directory itself.
69  * @is_visible:	Optional: Function to return permissions associated with an
70  *		attribute of the group. Will be called repeatedly for
71  *		each non-binary attribute in the group. Only read/write
72  *		permissions as well as SYSFS_PREALLOC are accepted. Must
73  *		return 0 if an attribute is not visible. The returned
74  *		value will replace static permissions defined in struct
75  *		attribute. Use SYSFS_GROUP_VISIBLE() when assigning this
76  *		callback to specify separate _group_visible() and
77  *		_attr_visible() handlers.
78  * @is_bin_visible:
79  *		Optional: Function to return permissions associated with a
80  *		binary attribute of the group. Will be called repeatedly
81  *		for each binary attribute in the group. Only read/write
82  *		permissions as well as SYSFS_PREALLOC (and the
83  *		visibility flags for named groups) are accepted. Must
84  *		return 0 if a binary attribute is not visible. The
85  *		returned value will replace static permissions defined
86  *		in struct bin_attribute. If @is_visible is not set, Use
87  *		SYSFS_GROUP_VISIBLE() when assigning this callback to
88  *		specify separate _group_visible() and _attr_visible()
89  *		handlers.
90  * @bin_size:
91  *		Optional: Function to return the size of a binary attribute
92  *		of the group. Will be called repeatedly for each binary
93  *		attribute in the group. Overwrites the size field embedded
94  *		inside the attribute itself.
95  * @attrs:	Pointer to NULL terminated list of attributes.
96  * @bin_attrs:	Pointer to NULL terminated list of binary attributes.
97  *		Either attrs or bin_attrs or both must be provided.
98  */
99 struct attribute_group {
100 	const char		*name;
101 	umode_t			(*is_visible)(struct kobject *,
102 					      struct attribute *, int);
103 	umode_t			(*is_bin_visible)(struct kobject *,
104 						  const struct bin_attribute *, int);
105 	size_t			(*bin_size)(struct kobject *,
106 					    const struct bin_attribute *,
107 					    int);
108 	struct attribute	**attrs;
109 	const struct bin_attribute	*const *bin_attrs;
110 };
111 
112 #define SYSFS_PREALLOC		010000
113 #define SYSFS_GROUP_INVISIBLE	020000
114 
115 /*
116  * DEFINE_SYSFS_GROUP_VISIBLE(name):
117  *	A helper macro to pair with the assignment of ".is_visible =
118  *	SYSFS_GROUP_VISIBLE(name)", that arranges for the directory
119  *	associated with a named attribute_group to optionally be hidden.
120  *	This allows for static declaration of attribute_groups, and the
121  *	simplification of attribute visibility lifetime that implies,
122  *	without polluting sysfs with empty attribute directories.
123  * Ex.
124  *
125  * static umode_t example_attr_visible(struct kobject *kobj,
126  *                                   struct attribute *attr, int n)
127  * {
128  *       if (example_attr_condition)
129  *               return 0;
130  *       else if (ro_attr_condition)
131  *               return 0444;
132  *       return a->mode;
133  * }
134  *
135  * static bool example_group_visible(struct kobject *kobj)
136  * {
137  *       if (example_group_condition)
138  *               return false;
139  *       return true;
140  * }
141  *
142  * DEFINE_SYSFS_GROUP_VISIBLE(example);
143  *
144  * static struct attribute_group example_group = {
145  *       .name = "example",
146  *       .is_visible = SYSFS_GROUP_VISIBLE(example),
147  *       .attrs = &example_attrs,
148  * };
149  *
150  * Note that it expects <name>_attr_visible and <name>_group_visible to
151  * be defined. For cases where individual attributes do not need
152  * separate visibility consideration, only entire group visibility at
153  * once, see DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE().
154  */
155 #define DEFINE_SYSFS_GROUP_VISIBLE(name)                             \
156 	static inline umode_t sysfs_group_visible_##name(            \
157 		struct kobject *kobj, struct attribute *attr, int n) \
158 	{                                                            \
159 		if (n == 0 && !name##_group_visible(kobj))           \
160 			return SYSFS_GROUP_INVISIBLE;                \
161 		return name##_attr_visible(kobj, attr, n);           \
162 	}
163 
164 /*
165  * DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE(name):
166  *	A helper macro to pair with SYSFS_GROUP_VISIBLE() that like
167  *	DEFINE_SYSFS_GROUP_VISIBLE() controls group visibility, but does
168  *	not require the implementation of a per-attribute visibility
169  *	callback.
170  * Ex.
171  *
172  * static bool example_group_visible(struct kobject *kobj)
173  * {
174  *       if (example_group_condition)
175  *               return false;
176  *       return true;
177  * }
178  *
179  * DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE(example);
180  *
181  * static struct attribute_group example_group = {
182  *       .name = "example",
183  *       .is_visible = SYSFS_GROUP_VISIBLE(example),
184  *       .attrs = &example_attrs,
185  * };
186  */
187 #define DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE(name)                   \
188 	static inline umode_t sysfs_group_visible_##name(         \
189 		struct kobject *kobj, struct attribute *a, int n) \
190 	{                                                         \
191 		if (n == 0 && !name##_group_visible(kobj))        \
192 			return SYSFS_GROUP_INVISIBLE;             \
193 		return a->mode;                                   \
194 	}
195 
196 /*
197  * Same as DEFINE_SYSFS_GROUP_VISIBLE, but for groups with only binary
198  * attributes. If an attribute_group defines both text and binary
199  * attributes, the group visibility is determined by the function
200  * specified to is_visible() not is_bin_visible()
201  */
202 #define DEFINE_SYSFS_BIN_GROUP_VISIBLE(name)                                   \
203 	static inline umode_t sysfs_group_visible_##name(                      \
204 		struct kobject *kobj, const struct bin_attribute *attr, int n) \
205 	{                                                                      \
206 		if (n == 0 && !name##_group_visible(kobj))                     \
207 			return SYSFS_GROUP_INVISIBLE;                          \
208 		return name##_attr_visible(kobj, attr, n);                     \
209 	}
210 
211 #define DEFINE_SIMPLE_SYSFS_BIN_GROUP_VISIBLE(name)                         \
212 	static inline umode_t sysfs_group_visible_##name(                   \
213 		struct kobject *kobj, const struct bin_attribute *a, int n) \
214 	{                                                                   \
215 		if (n == 0 && !name##_group_visible(kobj))                  \
216 			return SYSFS_GROUP_INVISIBLE;                       \
217 		return a->mode;                                             \
218 	}
219 
220 #define SYSFS_GROUP_VISIBLE(fn) sysfs_group_visible_##fn
221 
222 /*
223  * Use these macros to make defining attributes easier.
224  * See include/linux/device.h for examples..
225  */
226 
227 #define __ATTR(_name, _mode, _show, _store) {				\
228 	.attr = {.name = __stringify(_name),				\
229 		 .mode = VERIFY_OCTAL_PERMISSIONS(_mode) },		\
230 	.show	= _show,						\
231 	.store	= _store,						\
232 }
233 
234 #define __ATTR_PREALLOC(_name, _mode, _show, _store) {			\
235 	.attr = {.name = __stringify(_name),				\
236 		 .mode = SYSFS_PREALLOC | VERIFY_OCTAL_PERMISSIONS(_mode) },\
237 	.show	= _show,						\
238 	.store	= _store,						\
239 }
240 
241 #define __ATTR_RO(_name) {						\
242 	.attr	= { .name = __stringify(_name), .mode = 0444 },		\
243 	.show	= _name##_show,						\
244 }
245 
246 #define __ATTR_RO_MODE(_name, _mode) {					\
247 	.attr	= { .name = __stringify(_name),				\
248 		    .mode = VERIFY_OCTAL_PERMISSIONS(_mode) },		\
249 	.show	= _name##_show,						\
250 }
251 
252 #define __ATTR_RW_MODE(_name, _mode) {					\
253 	.attr	= { .name = __stringify(_name),				\
254 		    .mode = VERIFY_OCTAL_PERMISSIONS(_mode) },		\
255 	.show	= _name##_show,						\
256 	.store	= _name##_store,					\
257 }
258 
259 #define __ATTR_WO(_name) {						\
260 	.attr	= { .name = __stringify(_name), .mode = 0200 },		\
261 	.store	= _name##_store,					\
262 }
263 
264 #define __ATTR_RW(_name) __ATTR(_name, 0644, _name##_show, _name##_store)
265 
266 #define __ATTR_NULL { .attr = { .name = NULL } }
267 
268 #ifdef CONFIG_DEBUG_LOCK_ALLOC
269 #define __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) {	\
270 	.attr = {.name = __stringify(_name), .mode = _mode,	\
271 			.ignore_lockdep = true },		\
272 	.show		= _show,				\
273 	.store		= _store,				\
274 }
275 #else
276 #define __ATTR_IGNORE_LOCKDEP	__ATTR
277 #endif
278 
279 #define __ATTRIBUTE_GROUPS(_name)				\
280 static const struct attribute_group *_name##_groups[] = {	\
281 	&_name##_group,						\
282 	NULL,							\
283 }
284 
285 #define ATTRIBUTE_GROUPS(_name)					\
286 static const struct attribute_group _name##_group = {		\
287 	.attrs = _name##_attrs,					\
288 };								\
289 __ATTRIBUTE_GROUPS(_name)
290 
291 #define BIN_ATTRIBUTE_GROUPS(_name)				\
292 static const struct attribute_group _name##_group = {		\
293 	.bin_attrs = _name##_attrs,				\
294 };								\
295 __ATTRIBUTE_GROUPS(_name)
296 
297 struct file;
298 struct vm_area_struct;
299 struct address_space;
300 
301 struct bin_attribute {
302 	struct attribute	attr;
303 	size_t			size;
304 	void			*private;
305 	struct address_space *(*f_mapping)(void);
306 	ssize_t (*read)(struct file *, struct kobject *, const struct bin_attribute *,
307 			char *, loff_t, size_t);
308 	ssize_t (*write)(struct file *, struct kobject *, const struct bin_attribute *,
309 			 char *, loff_t, size_t);
310 	loff_t (*llseek)(struct file *, struct kobject *, const struct bin_attribute *,
311 			 loff_t, int);
312 	int (*mmap)(struct file *, struct kobject *, const struct bin_attribute *attr,
313 		    struct vm_area_struct *vma);
314 };
315 
316 /**
317  *	sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
318  *	@attr: struct bin_attribute to initialize
319  *
320  *	Initialize a dynamically allocated struct bin_attribute so we
321  *	can make lockdep happy.  This is a new requirement for
322  *	attributes and initially this is only needed when lockdep is
323  *	enabled.  Lockdep gives a nice error when your attribute is
324  *	added to sysfs if you don't have this.
325  */
326 #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
327 
328 /* macros to create static binary attributes easier */
329 #define __BIN_ATTR(_name, _mode, _read, _write, _size) {		\
330 	.attr = { .name = __stringify(_name), .mode = _mode },		\
331 	.read = _read,							\
332 	.write = _write,						\
333 	.size	= _size,						\
334 }
335 
336 #define __BIN_ATTR_RO(_name, _size)					\
337 	__BIN_ATTR(_name, 0444, _name##_read, NULL, _size)
338 
339 #define __BIN_ATTR_WO(_name, _size)					\
340 	__BIN_ATTR(_name, 0200, NULL, _name##_write, _size)
341 
342 #define __BIN_ATTR_RW(_name, _size)					\
343 	__BIN_ATTR(_name, 0644, _name##_read, _name##_write, _size)
344 
345 #define __BIN_ATTR_NULL __ATTR_NULL
346 
347 #define BIN_ATTR(_name, _mode, _read, _write, _size)			\
348 struct bin_attribute bin_attr_##_name = __BIN_ATTR(_name, _mode, _read,	\
349 					_write, _size)
350 
351 #define BIN_ATTR_RO(_name, _size)					\
352 struct bin_attribute bin_attr_##_name = __BIN_ATTR_RO(_name, _size)
353 
354 #define BIN_ATTR_WO(_name, _size)					\
355 struct bin_attribute bin_attr_##_name = __BIN_ATTR_WO(_name, _size)
356 
357 #define BIN_ATTR_RW(_name, _size)					\
358 struct bin_attribute bin_attr_##_name = __BIN_ATTR_RW(_name, _size)
359 
360 
361 #define __BIN_ATTR_ADMIN_RO(_name, _size)				\
362 	__BIN_ATTR(_name, 0400, _name##_read, NULL, _size)
363 
364 #define __BIN_ATTR_ADMIN_RW(_name, _size)					\
365 	__BIN_ATTR(_name, 0600, _name##_read, _name##_write, _size)
366 
367 #define BIN_ATTR_ADMIN_RO(_name, _size)					\
368 struct bin_attribute bin_attr_##_name = __BIN_ATTR_ADMIN_RO(_name, _size)
369 
370 #define BIN_ATTR_ADMIN_RW(_name, _size)					\
371 struct bin_attribute bin_attr_##_name = __BIN_ATTR_ADMIN_RW(_name, _size)
372 
373 #define __BIN_ATTR_SIMPLE_RO(_name, _mode)				\
374 	__BIN_ATTR(_name, _mode, sysfs_bin_attr_simple_read, NULL, 0)
375 
376 #define BIN_ATTR_SIMPLE_RO(_name)					\
377 struct bin_attribute bin_attr_##_name = __BIN_ATTR_SIMPLE_RO(_name, 0444)
378 
379 #define BIN_ATTR_SIMPLE_ADMIN_RO(_name)					\
380 struct bin_attribute bin_attr_##_name = __BIN_ATTR_SIMPLE_RO(_name, 0400)
381 
382 struct sysfs_ops {
383 	ssize_t	(*show)(struct kobject *, struct attribute *, char *);
384 	ssize_t	(*store)(struct kobject *, struct attribute *, const char *, size_t);
385 };
386 
387 #ifdef CONFIG_SYSFS
388 
389 int __must_check sysfs_create_dir_ns(struct kobject *kobj, const void *ns);
390 void sysfs_remove_dir(struct kobject *kobj);
391 int __must_check sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name,
392 				     const void *new_ns);
393 int __must_check sysfs_move_dir_ns(struct kobject *kobj,
394 				   struct kobject *new_parent_kobj,
395 				   const void *new_ns);
396 int __must_check sysfs_create_mount_point(struct kobject *parent_kobj,
397 					  const char *name);
398 void sysfs_remove_mount_point(struct kobject *parent_kobj,
399 			      const char *name);
400 
401 int __must_check sysfs_create_file_ns(struct kobject *kobj,
402 				      const struct attribute *attr,
403 				      const void *ns);
404 int __must_check sysfs_create_files(struct kobject *kobj,
405 				   const struct attribute * const *attr);
406 int __must_check sysfs_chmod_file(struct kobject *kobj,
407 				  const struct attribute *attr, umode_t mode);
408 struct kernfs_node *sysfs_break_active_protection(struct kobject *kobj,
409 						  const struct attribute *attr);
410 void sysfs_unbreak_active_protection(struct kernfs_node *kn);
411 void sysfs_remove_file_ns(struct kobject *kobj, const struct attribute *attr,
412 			  const void *ns);
413 bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr);
414 void sysfs_remove_files(struct kobject *kobj, const struct attribute * const *attr);
415 
416 int __must_check sysfs_create_bin_file(struct kobject *kobj,
417 				       const struct bin_attribute *attr);
418 void sysfs_remove_bin_file(struct kobject *kobj,
419 			   const struct bin_attribute *attr);
420 
421 int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
422 				   const char *name);
423 int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
424 					  struct kobject *target,
425 					  const char *name);
426 void sysfs_remove_link(struct kobject *kobj, const char *name);
427 
428 int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *target,
429 			 const char *old_name, const char *new_name,
430 			 const void *new_ns);
431 
432 void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
433 			const char *name);
434 
435 int __must_check sysfs_create_group(struct kobject *kobj,
436 				    const struct attribute_group *grp);
437 int __must_check sysfs_create_groups(struct kobject *kobj,
438 				     const struct attribute_group **groups);
439 int __must_check sysfs_update_groups(struct kobject *kobj,
440 				     const struct attribute_group **groups);
441 int sysfs_update_group(struct kobject *kobj,
442 		       const struct attribute_group *grp);
443 void sysfs_remove_group(struct kobject *kobj,
444 			const struct attribute_group *grp);
445 void sysfs_remove_groups(struct kobject *kobj,
446 			 const struct attribute_group **groups);
447 int sysfs_add_file_to_group(struct kobject *kobj,
448 			const struct attribute *attr, const char *group);
449 void sysfs_remove_file_from_group(struct kobject *kobj,
450 			const struct attribute *attr, const char *group);
451 int sysfs_merge_group(struct kobject *kobj,
452 		       const struct attribute_group *grp);
453 void sysfs_unmerge_group(struct kobject *kobj,
454 		       const struct attribute_group *grp);
455 int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name,
456 			    struct kobject *target, const char *link_name);
457 void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
458 				  const char *link_name);
459 int compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
460 					 struct kobject *target_kobj,
461 					 const char *target_name,
462 					 const char *symlink_name);
463 
464 void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
465 
466 int __must_check sysfs_init(void);
467 
468 static inline void sysfs_enable_ns(struct kernfs_node *kn)
469 {
470 	return kernfs_enable_ns(kn);
471 }
472 
473 int sysfs_file_change_owner(struct kobject *kobj, const char *name, kuid_t kuid,
474 			    kgid_t kgid);
475 int sysfs_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid);
476 int sysfs_link_change_owner(struct kobject *kobj, struct kobject *targ,
477 			    const char *name, kuid_t kuid, kgid_t kgid);
478 int sysfs_groups_change_owner(struct kobject *kobj,
479 			      const struct attribute_group **groups,
480 			      kuid_t kuid, kgid_t kgid);
481 int sysfs_group_change_owner(struct kobject *kobj,
482 			     const struct attribute_group *groups, kuid_t kuid,
483 			     kgid_t kgid);
484 __printf(2, 3)
485 int sysfs_emit(char *buf, const char *fmt, ...);
486 __printf(3, 4)
487 int sysfs_emit_at(char *buf, int at, const char *fmt, ...);
488 
489 ssize_t sysfs_bin_attr_simple_read(struct file *file, struct kobject *kobj,
490 				   const struct bin_attribute *attr, char *buf,
491 				   loff_t off, size_t count);
492 
493 #else /* CONFIG_SYSFS */
494 
495 static inline int sysfs_create_dir_ns(struct kobject *kobj, const void *ns)
496 {
497 	return 0;
498 }
499 
500 static inline void sysfs_remove_dir(struct kobject *kobj)
501 {
502 }
503 
504 static inline int sysfs_rename_dir_ns(struct kobject *kobj,
505 				      const char *new_name, const void *new_ns)
506 {
507 	return 0;
508 }
509 
510 static inline int sysfs_move_dir_ns(struct kobject *kobj,
511 				    struct kobject *new_parent_kobj,
512 				    const void *new_ns)
513 {
514 	return 0;
515 }
516 
517 static inline int sysfs_create_mount_point(struct kobject *parent_kobj,
518 					   const char *name)
519 {
520 	return 0;
521 }
522 
523 static inline void sysfs_remove_mount_point(struct kobject *parent_kobj,
524 					    const char *name)
525 {
526 }
527 
528 static inline int sysfs_create_file_ns(struct kobject *kobj,
529 				       const struct attribute *attr,
530 				       const void *ns)
531 {
532 	return 0;
533 }
534 
535 static inline int sysfs_create_files(struct kobject *kobj,
536 				    const struct attribute * const *attr)
537 {
538 	return 0;
539 }
540 
541 static inline int sysfs_chmod_file(struct kobject *kobj,
542 				   const struct attribute *attr, umode_t mode)
543 {
544 	return 0;
545 }
546 
547 static inline struct kernfs_node *
548 sysfs_break_active_protection(struct kobject *kobj,
549 			      const struct attribute *attr)
550 {
551 	return NULL;
552 }
553 
554 static inline void sysfs_unbreak_active_protection(struct kernfs_node *kn)
555 {
556 }
557 
558 static inline void sysfs_remove_file_ns(struct kobject *kobj,
559 					const struct attribute *attr,
560 					const void *ns)
561 {
562 }
563 
564 static inline bool sysfs_remove_file_self(struct kobject *kobj,
565 					  const struct attribute *attr)
566 {
567 	return false;
568 }
569 
570 static inline void sysfs_remove_files(struct kobject *kobj,
571 				     const struct attribute * const *attr)
572 {
573 }
574 
575 static inline int sysfs_create_bin_file(struct kobject *kobj,
576 					const struct bin_attribute *attr)
577 {
578 	return 0;
579 }
580 
581 static inline void sysfs_remove_bin_file(struct kobject *kobj,
582 					 const struct bin_attribute *attr)
583 {
584 }
585 
586 static inline int sysfs_create_link(struct kobject *kobj,
587 				    struct kobject *target, const char *name)
588 {
589 	return 0;
590 }
591 
592 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
593 					   struct kobject *target,
594 					   const char *name)
595 {
596 	return 0;
597 }
598 
599 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
600 {
601 }
602 
603 static inline int sysfs_rename_link_ns(struct kobject *k, struct kobject *t,
604 				       const char *old_name,
605 				       const char *new_name, const void *ns)
606 {
607 	return 0;
608 }
609 
610 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
611 				     const char *name)
612 {
613 }
614 
615 static inline int sysfs_create_group(struct kobject *kobj,
616 				     const struct attribute_group *grp)
617 {
618 	return 0;
619 }
620 
621 static inline int sysfs_create_groups(struct kobject *kobj,
622 				      const struct attribute_group **groups)
623 {
624 	return 0;
625 }
626 
627 static inline int sysfs_update_groups(struct kobject *kobj,
628 				      const struct attribute_group **groups)
629 {
630 	return 0;
631 }
632 
633 static inline int sysfs_update_group(struct kobject *kobj,
634 				const struct attribute_group *grp)
635 {
636 	return 0;
637 }
638 
639 static inline void sysfs_remove_group(struct kobject *kobj,
640 				      const struct attribute_group *grp)
641 {
642 }
643 
644 static inline void sysfs_remove_groups(struct kobject *kobj,
645 				       const struct attribute_group **groups)
646 {
647 }
648 
649 static inline int sysfs_add_file_to_group(struct kobject *kobj,
650 		const struct attribute *attr, const char *group)
651 {
652 	return 0;
653 }
654 
655 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
656 		const struct attribute *attr, const char *group)
657 {
658 }
659 
660 static inline int sysfs_merge_group(struct kobject *kobj,
661 		       const struct attribute_group *grp)
662 {
663 	return 0;
664 }
665 
666 static inline void sysfs_unmerge_group(struct kobject *kobj,
667 		       const struct attribute_group *grp)
668 {
669 }
670 
671 static inline int sysfs_add_link_to_group(struct kobject *kobj,
672 		const char *group_name, struct kobject *target,
673 		const char *link_name)
674 {
675 	return 0;
676 }
677 
678 static inline void sysfs_remove_link_from_group(struct kobject *kobj,
679 		const char *group_name, const char *link_name)
680 {
681 }
682 
683 static inline int compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
684 						       struct kobject *target_kobj,
685 						       const char *target_name,
686 						       const char *symlink_name)
687 {
688 	return 0;
689 }
690 
691 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
692 				const char *attr)
693 {
694 }
695 
696 static inline int __must_check sysfs_init(void)
697 {
698 	return 0;
699 }
700 
701 static inline void sysfs_enable_ns(struct kernfs_node *kn)
702 {
703 }
704 
705 static inline int sysfs_file_change_owner(struct kobject *kobj,
706 					  const char *name, kuid_t kuid,
707 					  kgid_t kgid)
708 {
709 	return 0;
710 }
711 
712 static inline int sysfs_link_change_owner(struct kobject *kobj,
713 					  struct kobject *targ,
714 					  const char *name, kuid_t kuid,
715 					  kgid_t kgid)
716 {
717 	return 0;
718 }
719 
720 static inline int sysfs_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid)
721 {
722 	return 0;
723 }
724 
725 static inline int sysfs_groups_change_owner(struct kobject *kobj,
726 			  const struct attribute_group **groups,
727 			  kuid_t kuid, kgid_t kgid)
728 {
729 	return 0;
730 }
731 
732 static inline int sysfs_group_change_owner(struct kobject *kobj,
733 					   const struct attribute_group *groups,
734 					   kuid_t kuid, kgid_t kgid)
735 {
736 	return 0;
737 }
738 
739 __printf(2, 3)
740 static inline int sysfs_emit(char *buf, const char *fmt, ...)
741 {
742 	return 0;
743 }
744 
745 __printf(3, 4)
746 static inline int sysfs_emit_at(char *buf, int at, const char *fmt, ...)
747 {
748 	return 0;
749 }
750 
751 static inline ssize_t sysfs_bin_attr_simple_read(struct file *file,
752 						 struct kobject *kobj,
753 						 const struct bin_attribute *attr,
754 						 char *buf, loff_t off,
755 						 size_t count)
756 {
757 	return 0;
758 }
759 #endif /* CONFIG_SYSFS */
760 
761 static inline int __must_check sysfs_create_file(struct kobject *kobj,
762 						 const struct attribute *attr)
763 {
764 	return sysfs_create_file_ns(kobj, attr, NULL);
765 }
766 
767 static inline void sysfs_remove_file(struct kobject *kobj,
768 				     const struct attribute *attr)
769 {
770 	sysfs_remove_file_ns(kobj, attr, NULL);
771 }
772 
773 static inline int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
774 				    const char *old_name, const char *new_name)
775 {
776 	return sysfs_rename_link_ns(kobj, target, old_name, new_name, NULL);
777 }
778 
779 static inline void sysfs_notify_dirent(struct kernfs_node *kn)
780 {
781 	kernfs_notify(kn);
782 }
783 
784 static inline struct kernfs_node *sysfs_get_dirent(struct kernfs_node *parent,
785 						   const char *name)
786 {
787 	return kernfs_find_and_get(parent, name);
788 }
789 
790 static inline struct kernfs_node *sysfs_get(struct kernfs_node *kn)
791 {
792 	kernfs_get(kn);
793 	return kn;
794 }
795 
796 static inline void sysfs_put(struct kernfs_node *kn)
797 {
798 	kernfs_put(kn);
799 }
800 
801 #endif /* _SYSFS_H_ */
802