• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * sysfs.h - definitions for the device driver filesystem
3  *
4  * Copyright (c) 2001,2002 Patrick Mochel
5  * Copyright (c) 2004 Silicon Graphics, Inc.
6  * Copyright (c) 2007 SUSE Linux Products GmbH
7  * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
8  *
9  * Please see Documentation/filesystems/sysfs.txt for more information.
10  */
11 
12 #ifndef _SYSFS_H_
13 #define _SYSFS_H_
14 
15 #include <linux/kernfs.h>
16 #include <linux/compiler.h>
17 #include <linux/errno.h>
18 #include <linux/list.h>
19 #include <linux/lockdep.h>
20 #include <linux/kobject_ns.h>
21 #include <linux/stat.h>
22 #include <linux/atomic.h>
23 
24 struct kobject;
25 struct module;
26 struct bin_attribute;
27 enum kobj_ns_type;
28 
29 struct attribute {
30 	const char		*name;
31 	umode_t			mode;
32 #ifdef CONFIG_DEBUG_LOCK_ALLOC
33 	bool			ignore_lockdep:1;
34 	struct lock_class_key	*key;
35 	struct lock_class_key	skey;
36 #endif
37 };
38 
39 /**
40  *	sysfs_attr_init - initialize a dynamically allocated sysfs attribute
41  *	@attr: struct attribute to initialize
42  *
43  *	Initialize a dynamically allocated struct attribute so we can
44  *	make lockdep happy.  This is a new requirement for attributes
45  *	and initially this is only needed when lockdep is enabled.
46  *	Lockdep gives a nice error when your attribute is added to
47  *	sysfs if you don't have this.
48  */
49 #ifdef CONFIG_DEBUG_LOCK_ALLOC
50 #define sysfs_attr_init(attr)				\
51 do {							\
52 	static struct lock_class_key __key;		\
53 							\
54 	(attr)->key = &__key;				\
55 } while (0)
56 #else
57 #define sysfs_attr_init(attr) do {} while (0)
58 #endif
59 
60 /**
61  * struct attribute_group - data structure used to declare an attribute group.
62  * @name:	Optional: Attribute group name
63  *		If specified, the attribute group will be created in
64  *		a new subdirectory with this name.
65  * @is_visible:	Optional: Function to return permissions associated with an
66  *		attribute of the group. Will be called repeatedly for each
67  *		non-binary attribute in the group. Only read/write
68  *		permissions as well as SYSFS_PREALLOC are accepted. Must
69  *		return 0 if an attribute is not visible. The returned value
70  *		will replace static permissions defined in struct attribute.
71  * @is_bin_visible:
72  *		Optional: Function to return permissions associated with a
73  *		binary attribute of the group. Will be called repeatedly
74  *		for each binary attribute in the group. Only read/write
75  *		permissions as well as SYSFS_PREALLOC are accepted. Must
76  *		return 0 if a binary attribute is not visible. The returned
77  *		value will replace static permissions defined in
78  *		struct bin_attribute.
79  * @attrs:	Pointer to NULL terminated list of attributes.
80  * @bin_attrs:	Pointer to NULL terminated list of binary attributes.
81  *		Either attrs or bin_attrs or both must be provided.
82  */
83 struct attribute_group {
84 	const char		*name;
85 	umode_t			(*is_visible)(struct kobject *,
86 					      struct attribute *, int);
87 	umode_t			(*is_bin_visible)(struct kobject *,
88 						  struct bin_attribute *, int);
89 	struct attribute	**attrs;
90 	struct bin_attribute	**bin_attrs;
91 };
92 
93 /**
94  * Use these macros to make defining attributes easier. See include/linux/device.h
95  * for examples..
96  */
97 
98 #define SYSFS_PREALLOC 010000
99 
100 #define __ATTR(_name, _mode, _show, _store) {				\
101 	.attr = {.name = __stringify(_name),				\
102 		 .mode = VERIFY_OCTAL_PERMISSIONS(_mode) },		\
103 	.show	= _show,						\
104 	.store	= _store,						\
105 }
106 
107 #define __ATTR_PREALLOC(_name, _mode, _show, _store) {			\
108 	.attr = {.name = __stringify(_name),				\
109 		 .mode = SYSFS_PREALLOC | VERIFY_OCTAL_PERMISSIONS(_mode) },\
110 	.show	= _show,						\
111 	.store	= _store,						\
112 }
113 
114 #define __ATTR_RO(_name) {						\
115 	.attr	= { .name = __stringify(_name), .mode = S_IRUGO },	\
116 	.show	= _name##_show,						\
117 }
118 
119 #define __ATTR_RO_MODE(_name, _mode) {					\
120 	.attr	= { .name = __stringify(_name),				\
121 		    .mode = VERIFY_OCTAL_PERMISSIONS(_mode) },		\
122 	.show	= _name##_show,						\
123 }
124 
125 #define __ATTR_WO(_name) {						\
126 	.attr	= { .name = __stringify(_name), .mode = S_IWUSR },	\
127 	.store	= _name##_store,					\
128 }
129 
130 #define __ATTR_RW(_name) __ATTR(_name, (S_IWUSR | S_IRUGO),		\
131 			 _name##_show, _name##_store)
132 
133 #define __ATTR_NULL { .attr = { .name = NULL } }
134 
135 #ifdef CONFIG_DEBUG_LOCK_ALLOC
136 #define __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) {	\
137 	.attr = {.name = __stringify(_name), .mode = _mode,	\
138 			.ignore_lockdep = true },		\
139 	.show		= _show,				\
140 	.store		= _store,				\
141 }
142 #else
143 #define __ATTR_IGNORE_LOCKDEP	__ATTR
144 #endif
145 
146 #define __ATTRIBUTE_GROUPS(_name)				\
147 static const struct attribute_group *_name##_groups[] = {	\
148 	&_name##_group,						\
149 	NULL,							\
150 }
151 
152 #define ATTRIBUTE_GROUPS(_name)					\
153 static const struct attribute_group _name##_group = {		\
154 	.attrs = _name##_attrs,					\
155 };								\
156 __ATTRIBUTE_GROUPS(_name)
157 
158 struct file;
159 struct vm_area_struct;
160 
161 struct bin_attribute {
162 	struct attribute	attr;
163 	size_t			size;
164 	void			*private;
165 	ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *,
166 			char *, loff_t, size_t);
167 	ssize_t (*write)(struct file *, struct kobject *, struct bin_attribute *,
168 			 char *, loff_t, size_t);
169 	int (*mmap)(struct file *, struct kobject *, struct bin_attribute *attr,
170 		    struct vm_area_struct *vma);
171 };
172 
173 /**
174  *	sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
175  *	@attr: struct bin_attribute to initialize
176  *
177  *	Initialize a dynamically allocated struct bin_attribute so we
178  *	can make lockdep happy.  This is a new requirement for
179  *	attributes and initially this is only needed when lockdep is
180  *	enabled.  Lockdep gives a nice error when your attribute is
181  *	added to sysfs if you don't have this.
182  */
183 #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
184 
185 /* macros to create static binary attributes easier */
186 #define __BIN_ATTR(_name, _mode, _read, _write, _size) {		\
187 	.attr = { .name = __stringify(_name), .mode = _mode },		\
188 	.read	= _read,						\
189 	.write	= _write,						\
190 	.size	= _size,						\
191 }
192 
193 #define __BIN_ATTR_RO(_name, _size) {					\
194 	.attr	= { .name = __stringify(_name), .mode = S_IRUGO },	\
195 	.read	= _name##_read,						\
196 	.size	= _size,						\
197 }
198 
199 #define __BIN_ATTR_RW(_name, _size) __BIN_ATTR(_name,			\
200 				   (S_IWUSR | S_IRUGO), _name##_read,	\
201 				   _name##_write, _size)
202 
203 #define __BIN_ATTR_NULL __ATTR_NULL
204 
205 #define BIN_ATTR(_name, _mode, _read, _write, _size)			\
206 struct bin_attribute bin_attr_##_name = __BIN_ATTR(_name, _mode, _read,	\
207 					_write, _size)
208 
209 #define BIN_ATTR_RO(_name, _size)					\
210 struct bin_attribute bin_attr_##_name = __BIN_ATTR_RO(_name, _size)
211 
212 #define BIN_ATTR_RW(_name, _size)					\
213 struct bin_attribute bin_attr_##_name = __BIN_ATTR_RW(_name, _size)
214 
215 struct sysfs_ops {
216 	ssize_t	(*show)(struct kobject *, struct attribute *, char *);
217 	ssize_t	(*store)(struct kobject *, struct attribute *, const char *, size_t);
218 };
219 
220 #ifdef CONFIG_SYSFS
221 
222 int __must_check sysfs_create_dir_ns(struct kobject *kobj, const void *ns);
223 void sysfs_remove_dir(struct kobject *kobj);
224 int __must_check sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name,
225 				     const void *new_ns);
226 int __must_check sysfs_move_dir_ns(struct kobject *kobj,
227 				   struct kobject *new_parent_kobj,
228 				   const void *new_ns);
229 int __must_check sysfs_create_mount_point(struct kobject *parent_kobj,
230 					  const char *name);
231 void sysfs_remove_mount_point(struct kobject *parent_kobj,
232 			      const char *name);
233 
234 int __must_check sysfs_create_file_ns(struct kobject *kobj,
235 				      const struct attribute *attr,
236 				      const void *ns);
237 int __must_check sysfs_create_files(struct kobject *kobj,
238 				   const struct attribute **attr);
239 int __must_check sysfs_chmod_file(struct kobject *kobj,
240 				  const struct attribute *attr, umode_t mode);
241 void sysfs_remove_file_ns(struct kobject *kobj, const struct attribute *attr,
242 			  const void *ns);
243 bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr);
244 void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
245 
246 int __must_check sysfs_create_bin_file(struct kobject *kobj,
247 				       const struct bin_attribute *attr);
248 void sysfs_remove_bin_file(struct kobject *kobj,
249 			   const struct bin_attribute *attr);
250 
251 int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
252 				   const char *name);
253 int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
254 					  struct kobject *target,
255 					  const char *name);
256 void sysfs_remove_link(struct kobject *kobj, const char *name);
257 
258 int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *target,
259 			 const char *old_name, const char *new_name,
260 			 const void *new_ns);
261 
262 void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
263 			const char *name);
264 
265 int __must_check sysfs_create_group(struct kobject *kobj,
266 				    const struct attribute_group *grp);
267 int __must_check sysfs_create_groups(struct kobject *kobj,
268 				     const struct attribute_group **groups);
269 int sysfs_update_group(struct kobject *kobj,
270 		       const struct attribute_group *grp);
271 void sysfs_remove_group(struct kobject *kobj,
272 			const struct attribute_group *grp);
273 void sysfs_remove_groups(struct kobject *kobj,
274 			 const struct attribute_group **groups);
275 int sysfs_add_file_to_group(struct kobject *kobj,
276 			const struct attribute *attr, const char *group);
277 void sysfs_remove_file_from_group(struct kobject *kobj,
278 			const struct attribute *attr, const char *group);
279 int sysfs_merge_group(struct kobject *kobj,
280 		       const struct attribute_group *grp);
281 void sysfs_unmerge_group(struct kobject *kobj,
282 		       const struct attribute_group *grp);
283 int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name,
284 			    struct kobject *target, const char *link_name);
285 void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
286 				  const char *link_name);
287 int __compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
288 				      struct kobject *target_kobj,
289 				      const char *target_name);
290 
291 void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
292 
293 int __must_check sysfs_init(void);
294 
sysfs_enable_ns(struct kernfs_node * kn)295 static inline void sysfs_enable_ns(struct kernfs_node *kn)
296 {
297 	return kernfs_enable_ns(kn);
298 }
299 
300 #else /* CONFIG_SYSFS */
301 
sysfs_create_dir_ns(struct kobject * kobj,const void * ns)302 static inline int sysfs_create_dir_ns(struct kobject *kobj, const void *ns)
303 {
304 	return 0;
305 }
306 
sysfs_remove_dir(struct kobject * kobj)307 static inline void sysfs_remove_dir(struct kobject *kobj)
308 {
309 }
310 
sysfs_rename_dir_ns(struct kobject * kobj,const char * new_name,const void * new_ns)311 static inline int sysfs_rename_dir_ns(struct kobject *kobj,
312 				      const char *new_name, const void *new_ns)
313 {
314 	return 0;
315 }
316 
sysfs_move_dir_ns(struct kobject * kobj,struct kobject * new_parent_kobj,const void * new_ns)317 static inline int sysfs_move_dir_ns(struct kobject *kobj,
318 				    struct kobject *new_parent_kobj,
319 				    const void *new_ns)
320 {
321 	return 0;
322 }
323 
sysfs_create_mount_point(struct kobject * parent_kobj,const char * name)324 static inline int sysfs_create_mount_point(struct kobject *parent_kobj,
325 					   const char *name)
326 {
327 	return 0;
328 }
329 
sysfs_remove_mount_point(struct kobject * parent_kobj,const char * name)330 static inline void sysfs_remove_mount_point(struct kobject *parent_kobj,
331 					    const char *name)
332 {
333 }
334 
sysfs_create_file_ns(struct kobject * kobj,const struct attribute * attr,const void * ns)335 static inline int sysfs_create_file_ns(struct kobject *kobj,
336 				       const struct attribute *attr,
337 				       const void *ns)
338 {
339 	return 0;
340 }
341 
sysfs_create_files(struct kobject * kobj,const struct attribute ** attr)342 static inline int sysfs_create_files(struct kobject *kobj,
343 				    const struct attribute **attr)
344 {
345 	return 0;
346 }
347 
sysfs_chmod_file(struct kobject * kobj,const struct attribute * attr,umode_t mode)348 static inline int sysfs_chmod_file(struct kobject *kobj,
349 				   const struct attribute *attr, umode_t mode)
350 {
351 	return 0;
352 }
353 
sysfs_remove_file_ns(struct kobject * kobj,const struct attribute * attr,const void * ns)354 static inline void sysfs_remove_file_ns(struct kobject *kobj,
355 					const struct attribute *attr,
356 					const void *ns)
357 {
358 }
359 
sysfs_remove_file_self(struct kobject * kobj,const struct attribute * attr)360 static inline bool sysfs_remove_file_self(struct kobject *kobj,
361 					  const struct attribute *attr)
362 {
363 	return false;
364 }
365 
sysfs_remove_files(struct kobject * kobj,const struct attribute ** attr)366 static inline void sysfs_remove_files(struct kobject *kobj,
367 				     const struct attribute **attr)
368 {
369 }
370 
sysfs_create_bin_file(struct kobject * kobj,const struct bin_attribute * attr)371 static inline int sysfs_create_bin_file(struct kobject *kobj,
372 					const struct bin_attribute *attr)
373 {
374 	return 0;
375 }
376 
sysfs_remove_bin_file(struct kobject * kobj,const struct bin_attribute * attr)377 static inline void sysfs_remove_bin_file(struct kobject *kobj,
378 					 const struct bin_attribute *attr)
379 {
380 }
381 
sysfs_create_link(struct kobject * kobj,struct kobject * target,const char * name)382 static inline int sysfs_create_link(struct kobject *kobj,
383 				    struct kobject *target, const char *name)
384 {
385 	return 0;
386 }
387 
sysfs_create_link_nowarn(struct kobject * kobj,struct kobject * target,const char * name)388 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
389 					   struct kobject *target,
390 					   const char *name)
391 {
392 	return 0;
393 }
394 
sysfs_remove_link(struct kobject * kobj,const char * name)395 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
396 {
397 }
398 
sysfs_rename_link_ns(struct kobject * k,struct kobject * t,const char * old_name,const char * new_name,const void * ns)399 static inline int sysfs_rename_link_ns(struct kobject *k, struct kobject *t,
400 				       const char *old_name,
401 				       const char *new_name, const void *ns)
402 {
403 	return 0;
404 }
405 
sysfs_delete_link(struct kobject * k,struct kobject * t,const char * name)406 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
407 				     const char *name)
408 {
409 }
410 
sysfs_create_group(struct kobject * kobj,const struct attribute_group * grp)411 static inline int sysfs_create_group(struct kobject *kobj,
412 				     const struct attribute_group *grp)
413 {
414 	return 0;
415 }
416 
sysfs_create_groups(struct kobject * kobj,const struct attribute_group ** groups)417 static inline int sysfs_create_groups(struct kobject *kobj,
418 				      const struct attribute_group **groups)
419 {
420 	return 0;
421 }
422 
sysfs_update_group(struct kobject * kobj,const struct attribute_group * grp)423 static inline int sysfs_update_group(struct kobject *kobj,
424 				const struct attribute_group *grp)
425 {
426 	return 0;
427 }
428 
sysfs_remove_group(struct kobject * kobj,const struct attribute_group * grp)429 static inline void sysfs_remove_group(struct kobject *kobj,
430 				      const struct attribute_group *grp)
431 {
432 }
433 
sysfs_remove_groups(struct kobject * kobj,const struct attribute_group ** groups)434 static inline void sysfs_remove_groups(struct kobject *kobj,
435 				       const struct attribute_group **groups)
436 {
437 }
438 
sysfs_add_file_to_group(struct kobject * kobj,const struct attribute * attr,const char * group)439 static inline int sysfs_add_file_to_group(struct kobject *kobj,
440 		const struct attribute *attr, const char *group)
441 {
442 	return 0;
443 }
444 
sysfs_remove_file_from_group(struct kobject * kobj,const struct attribute * attr,const char * group)445 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
446 		const struct attribute *attr, const char *group)
447 {
448 }
449 
sysfs_merge_group(struct kobject * kobj,const struct attribute_group * grp)450 static inline int sysfs_merge_group(struct kobject *kobj,
451 		       const struct attribute_group *grp)
452 {
453 	return 0;
454 }
455 
sysfs_unmerge_group(struct kobject * kobj,const struct attribute_group * grp)456 static inline void sysfs_unmerge_group(struct kobject *kobj,
457 		       const struct attribute_group *grp)
458 {
459 }
460 
sysfs_add_link_to_group(struct kobject * kobj,const char * group_name,struct kobject * target,const char * link_name)461 static inline int sysfs_add_link_to_group(struct kobject *kobj,
462 		const char *group_name, struct kobject *target,
463 		const char *link_name)
464 {
465 	return 0;
466 }
467 
sysfs_remove_link_from_group(struct kobject * kobj,const char * group_name,const char * link_name)468 static inline void sysfs_remove_link_from_group(struct kobject *kobj,
469 		const char *group_name, const char *link_name)
470 {
471 }
472 
__compat_only_sysfs_link_entry_to_kobj(struct kobject * kobj,struct kobject * target_kobj,const char * target_name)473 static inline int __compat_only_sysfs_link_entry_to_kobj(
474 	struct kobject *kobj,
475 	struct kobject *target_kobj,
476 	const char *target_name)
477 {
478 	return 0;
479 }
480 
sysfs_notify(struct kobject * kobj,const char * dir,const char * attr)481 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
482 				const char *attr)
483 {
484 }
485 
sysfs_init(void)486 static inline int __must_check sysfs_init(void)
487 {
488 	return 0;
489 }
490 
sysfs_enable_ns(struct kernfs_node * kn)491 static inline void sysfs_enable_ns(struct kernfs_node *kn)
492 {
493 }
494 
495 #endif /* CONFIG_SYSFS */
496 
sysfs_create_file(struct kobject * kobj,const struct attribute * attr)497 static inline int __must_check sysfs_create_file(struct kobject *kobj,
498 						 const struct attribute *attr)
499 {
500 	return sysfs_create_file_ns(kobj, attr, NULL);
501 }
502 
sysfs_remove_file(struct kobject * kobj,const struct attribute * attr)503 static inline void sysfs_remove_file(struct kobject *kobj,
504 				     const struct attribute *attr)
505 {
506 	sysfs_remove_file_ns(kobj, attr, NULL);
507 }
508 
sysfs_rename_link(struct kobject * kobj,struct kobject * target,const char * old_name,const char * new_name)509 static inline int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
510 				    const char *old_name, const char *new_name)
511 {
512 	return sysfs_rename_link_ns(kobj, target, old_name, new_name, NULL);
513 }
514 
sysfs_notify_dirent(struct kernfs_node * kn)515 static inline void sysfs_notify_dirent(struct kernfs_node *kn)
516 {
517 	kernfs_notify(kn);
518 }
519 
sysfs_get_dirent(struct kernfs_node * parent,const unsigned char * name)520 static inline struct kernfs_node *sysfs_get_dirent(struct kernfs_node *parent,
521 						   const unsigned char *name)
522 {
523 	return kernfs_find_and_get(parent, name);
524 }
525 
sysfs_get(struct kernfs_node * kn)526 static inline struct kernfs_node *sysfs_get(struct kernfs_node *kn)
527 {
528 	kernfs_get(kn);
529 	return kn;
530 }
531 
sysfs_put(struct kernfs_node * kn)532 static inline void sysfs_put(struct kernfs_node *kn)
533 {
534 	kernfs_put(kn);
535 }
536 
537 #endif /* _SYSFS_H_ */
538