xref: /linux-6.15/include/linux/sysfs.h (revision 6482f554)
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 <[email protected]>
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/compiler.h>
16 #include <linux/errno.h>
17 #include <linux/list.h>
18 #include <linux/lockdep.h>
19 #include <linux/kobject_ns.h>
20 #include <asm/atomic.h>
21 
22 struct kobject;
23 struct module;
24 enum kobj_ns_type;
25 
26 struct attribute {
27 	const char		*name;
28 	mode_t			mode;
29 #ifdef CONFIG_DEBUG_LOCK_ALLOC
30 	struct lock_class_key	*key;
31 	struct lock_class_key	skey;
32 #endif
33 };
34 
35 /**
36  *	sysfs_attr_init - initialize a dynamically allocated sysfs attribute
37  *	@attr: struct attribute to initialize
38  *
39  *	Initialize a dynamically allocated struct attribute so we can
40  *	make lockdep happy.  This is a new requirement for attributes
41  *	and initially this is only needed when lockdep is enabled.
42  *	Lockdep gives a nice error when your attribute is added to
43  *	sysfs if you don't have this.
44  */
45 #ifdef CONFIG_DEBUG_LOCK_ALLOC
46 #define sysfs_attr_init(attr)				\
47 do {							\
48 	static struct lock_class_key __key;		\
49 							\
50 	(attr)->key = &__key;				\
51 } while(0)
52 #else
53 #define sysfs_attr_init(attr) do {} while(0)
54 #endif
55 
56 struct attribute_group {
57 	const char		*name;
58 	mode_t			(*is_visible)(struct kobject *,
59 					      struct attribute *, int);
60 	struct attribute	**attrs;
61 };
62 
63 
64 
65 /**
66  * Use these macros to make defining attributes easier. See include/linux/device.h
67  * for examples..
68  */
69 
70 #define __ATTR(_name,_mode,_show,_store) { \
71 	.attr = {.name = __stringify(_name), .mode = _mode },	\
72 	.show	= _show,					\
73 	.store	= _store,					\
74 }
75 
76 #define __ATTR_RO(_name) { \
77 	.attr	= { .name = __stringify(_name), .mode = 0444 },	\
78 	.show	= _name##_show,					\
79 }
80 
81 #define __ATTR_NULL { .attr = { .name = NULL } }
82 
83 #define attr_name(_attr) (_attr).attr.name
84 
85 struct file;
86 struct vm_area_struct;
87 
88 struct bin_attribute {
89 	struct attribute	attr;
90 	size_t			size;
91 	void			*private;
92 	ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *,
93 			char *, loff_t, size_t);
94 	ssize_t (*write)(struct file *,struct kobject *, struct bin_attribute *,
95 			 char *, loff_t, size_t);
96 	int (*mmap)(struct file *, struct kobject *, struct bin_attribute *attr,
97 		    struct vm_area_struct *vma);
98 };
99 
100 /**
101  *	sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
102  *	@attr: struct bin_attribute to initialize
103  *
104  *	Initialize a dynamically allocated struct bin_attribute so we
105  *	can make lockdep happy.  This is a new requirement for
106  *	attributes and initially this is only needed when lockdep is
107  *	enabled.  Lockdep gives a nice error when your attribute is
108  *	added to sysfs if you don't have this.
109  */
110 #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
111 
112 struct sysfs_ops {
113 	ssize_t	(*show)(struct kobject *, struct attribute *,char *);
114 	ssize_t	(*store)(struct kobject *,struct attribute *,const char *, size_t);
115 };
116 
117 struct sysfs_dirent;
118 
119 #ifdef CONFIG_SYSFS
120 
121 int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
122 			    void *data, struct module *owner);
123 
124 int __must_check sysfs_create_dir(struct kobject *kobj);
125 void sysfs_remove_dir(struct kobject *kobj);
126 int __must_check sysfs_rename_dir(struct kobject *kobj, const char *new_name);
127 int __must_check sysfs_move_dir(struct kobject *kobj,
128 				struct kobject *new_parent_kobj);
129 
130 int __must_check sysfs_create_file(struct kobject *kobj,
131 				   const struct attribute *attr);
132 int __must_check sysfs_create_files(struct kobject *kobj,
133 				   const struct attribute **attr);
134 int __must_check sysfs_chmod_file(struct kobject *kobj,
135 				  const struct attribute *attr, mode_t mode);
136 void sysfs_remove_file(struct kobject *kobj, const struct attribute *attr);
137 void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
138 
139 int __must_check sysfs_create_bin_file(struct kobject *kobj,
140 				       const struct bin_attribute *attr);
141 void sysfs_remove_bin_file(struct kobject *kobj,
142 			   const struct bin_attribute *attr);
143 
144 int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
145 				   const char *name);
146 int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
147 					  struct kobject *target,
148 					  const char *name);
149 void sysfs_remove_link(struct kobject *kobj, const char *name);
150 
151 int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
152 			const char *old_name, const char *new_name);
153 
154 void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
155 			const char *name);
156 
157 int __must_check sysfs_create_group(struct kobject *kobj,
158 				    const struct attribute_group *grp);
159 int sysfs_update_group(struct kobject *kobj,
160 		       const struct attribute_group *grp);
161 void sysfs_remove_group(struct kobject *kobj,
162 			const struct attribute_group *grp);
163 int sysfs_add_file_to_group(struct kobject *kobj,
164 			const struct attribute *attr, const char *group);
165 void sysfs_remove_file_from_group(struct kobject *kobj,
166 			const struct attribute *attr, const char *group);
167 
168 void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
169 void sysfs_notify_dirent(struct sysfs_dirent *sd);
170 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
171 				      const void *ns,
172 				      const unsigned char *name);
173 struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd);
174 void sysfs_put(struct sysfs_dirent *sd);
175 void sysfs_printk_last_file(void);
176 
177 /* Called to clear a ns tag when it is no longer valid */
178 void sysfs_exit_ns(enum kobj_ns_type type, const void *tag);
179 
180 int __must_check sysfs_init(void);
181 
182 #else /* CONFIG_SYSFS */
183 
184 static inline int sysfs_schedule_callback(struct kobject *kobj,
185 		void (*func)(void *), void *data, struct module *owner)
186 {
187 	return -ENOSYS;
188 }
189 
190 static inline int sysfs_create_dir(struct kobject *kobj)
191 {
192 	return 0;
193 }
194 
195 static inline void sysfs_remove_dir(struct kobject *kobj)
196 {
197 }
198 
199 static inline int sysfs_rename_dir(struct kobject *kobj, const char *new_name)
200 {
201 	return 0;
202 }
203 
204 static inline int sysfs_move_dir(struct kobject *kobj,
205 				 struct kobject *new_parent_kobj)
206 {
207 	return 0;
208 }
209 
210 static inline int sysfs_create_file(struct kobject *kobj,
211 				    const struct attribute *attr)
212 {
213 	return 0;
214 }
215 
216 static inline int sysfs_create_files(struct kobject *kobj,
217 				    const struct attribute **attr)
218 {
219 	return 0;
220 }
221 
222 static inline int sysfs_chmod_file(struct kobject *kobj,
223 				   const struct attribute *attr, mode_t mode)
224 {
225 	return 0;
226 }
227 
228 static inline void sysfs_remove_file(struct kobject *kobj,
229 				     const struct attribute *attr)
230 {
231 }
232 
233 static inline void sysfs_remove_files(struct kobject *kobj,
234 				     const struct attribute **attr)
235 {
236 }
237 
238 static inline int sysfs_create_bin_file(struct kobject *kobj,
239 					const struct bin_attribute *attr)
240 {
241 	return 0;
242 }
243 
244 static inline void sysfs_remove_bin_file(struct kobject *kobj,
245 					 const struct bin_attribute *attr)
246 {
247 }
248 
249 static inline int sysfs_create_link(struct kobject *kobj,
250 				    struct kobject *target, const char *name)
251 {
252 	return 0;
253 }
254 
255 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
256 					   struct kobject *target,
257 					   const char *name)
258 {
259 	return 0;
260 }
261 
262 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
263 {
264 }
265 
266 static inline int sysfs_rename_link(struct kobject *k, struct kobject *t,
267 				    const char *old_name, const char *new_name)
268 {
269 	return 0;
270 }
271 
272 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
273 				     const char *name)
274 {
275 }
276 
277 static inline int sysfs_create_group(struct kobject *kobj,
278 				     const struct attribute_group *grp)
279 {
280 	return 0;
281 }
282 
283 static inline int sysfs_update_group(struct kobject *kobj,
284 				const struct attribute_group *grp)
285 {
286 	return 0;
287 }
288 
289 static inline void sysfs_remove_group(struct kobject *kobj,
290 				      const struct attribute_group *grp)
291 {
292 }
293 
294 static inline int sysfs_add_file_to_group(struct kobject *kobj,
295 		const struct attribute *attr, const char *group)
296 {
297 	return 0;
298 }
299 
300 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
301 		const struct attribute *attr, const char *group)
302 {
303 }
304 
305 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
306 				const char *attr)
307 {
308 }
309 static inline void sysfs_notify_dirent(struct sysfs_dirent *sd)
310 {
311 }
312 static inline
313 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
314 				      const void *ns,
315 				      const unsigned char *name)
316 {
317 	return NULL;
318 }
319 static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd)
320 {
321 	return NULL;
322 }
323 static inline void sysfs_put(struct sysfs_dirent *sd)
324 {
325 }
326 
327 static inline void sysfs_exit_ns(int type, const void *tag)
328 {
329 }
330 
331 static inline int __must_check sysfs_init(void)
332 {
333 	return 0;
334 }
335 
336 static inline void sysfs_printk_last_file(void)
337 {
338 }
339 
340 #endif /* CONFIG_SYSFS */
341 
342 #endif /* _SYSFS_H_ */
343