xref: /linux-6.15/include/linux/sysfs.h (revision 3e4cd073)
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 int sysfs_merge_group(struct kobject *kobj,
168 		       const struct attribute_group *grp);
169 void sysfs_unmerge_group(struct kobject *kobj,
170 		       const struct attribute_group *grp);
171 
172 void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
173 void sysfs_notify_dirent(struct sysfs_dirent *sd);
174 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
175 				      const void *ns,
176 				      const unsigned char *name);
177 struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd);
178 void sysfs_put(struct sysfs_dirent *sd);
179 
180 /* Called to clear a ns tag when it is no longer valid */
181 void sysfs_exit_ns(enum kobj_ns_type type, const void *tag);
182 
183 int __must_check sysfs_init(void);
184 
185 #else /* CONFIG_SYSFS */
186 
187 static inline int sysfs_schedule_callback(struct kobject *kobj,
188 		void (*func)(void *), void *data, struct module *owner)
189 {
190 	return -ENOSYS;
191 }
192 
193 static inline int sysfs_create_dir(struct kobject *kobj)
194 {
195 	return 0;
196 }
197 
198 static inline void sysfs_remove_dir(struct kobject *kobj)
199 {
200 }
201 
202 static inline int sysfs_rename_dir(struct kobject *kobj, const char *new_name)
203 {
204 	return 0;
205 }
206 
207 static inline int sysfs_move_dir(struct kobject *kobj,
208 				 struct kobject *new_parent_kobj)
209 {
210 	return 0;
211 }
212 
213 static inline int sysfs_create_file(struct kobject *kobj,
214 				    const struct attribute *attr)
215 {
216 	return 0;
217 }
218 
219 static inline int sysfs_create_files(struct kobject *kobj,
220 				    const struct attribute **attr)
221 {
222 	return 0;
223 }
224 
225 static inline int sysfs_chmod_file(struct kobject *kobj,
226 				   const struct attribute *attr, mode_t mode)
227 {
228 	return 0;
229 }
230 
231 static inline void sysfs_remove_file(struct kobject *kobj,
232 				     const struct attribute *attr)
233 {
234 }
235 
236 static inline void sysfs_remove_files(struct kobject *kobj,
237 				     const struct attribute **attr)
238 {
239 }
240 
241 static inline int sysfs_create_bin_file(struct kobject *kobj,
242 					const struct bin_attribute *attr)
243 {
244 	return 0;
245 }
246 
247 static inline void sysfs_remove_bin_file(struct kobject *kobj,
248 					 const struct bin_attribute *attr)
249 {
250 }
251 
252 static inline int sysfs_create_link(struct kobject *kobj,
253 				    struct kobject *target, const char *name)
254 {
255 	return 0;
256 }
257 
258 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
259 					   struct kobject *target,
260 					   const char *name)
261 {
262 	return 0;
263 }
264 
265 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
266 {
267 }
268 
269 static inline int sysfs_rename_link(struct kobject *k, struct kobject *t,
270 				    const char *old_name, const char *new_name)
271 {
272 	return 0;
273 }
274 
275 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
276 				     const char *name)
277 {
278 }
279 
280 static inline int sysfs_create_group(struct kobject *kobj,
281 				     const struct attribute_group *grp)
282 {
283 	return 0;
284 }
285 
286 static inline int sysfs_update_group(struct kobject *kobj,
287 				const struct attribute_group *grp)
288 {
289 	return 0;
290 }
291 
292 static inline void sysfs_remove_group(struct kobject *kobj,
293 				      const struct attribute_group *grp)
294 {
295 }
296 
297 static inline int sysfs_add_file_to_group(struct kobject *kobj,
298 		const struct attribute *attr, const char *group)
299 {
300 	return 0;
301 }
302 
303 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
304 		const struct attribute *attr, const char *group)
305 {
306 }
307 
308 static inline int sysfs_merge_group(struct kobject *kobj,
309 		       const struct attribute_group *grp)
310 {
311 	return 0;
312 }
313 
314 static inline void sysfs_unmerge_group(struct kobject *kobj,
315 		       const struct attribute_group *grp)
316 {
317 }
318 
319 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
320 				const char *attr)
321 {
322 }
323 static inline void sysfs_notify_dirent(struct sysfs_dirent *sd)
324 {
325 }
326 static inline
327 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
328 				      const void *ns,
329 				      const unsigned char *name)
330 {
331 	return NULL;
332 }
333 static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd)
334 {
335 	return NULL;
336 }
337 static inline void sysfs_put(struct sysfs_dirent *sd)
338 {
339 }
340 
341 static inline void sysfs_exit_ns(int type, const void *tag)
342 {
343 }
344 
345 static inline int __must_check sysfs_init(void)
346 {
347 	return 0;
348 }
349 
350 #endif /* CONFIG_SYSFS */
351 
352 #endif /* _SYSFS_H_ */
353