xref: /linux-6.15/include/linux/sysfs.h (revision 4dc7ccf7)
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 <asm/atomic.h>
20 
21 struct kobject;
22 struct module;
23 
24 /* FIXME
25  * The *owner field is no longer used.
26  * x86 tree has been cleaned up. The owner
27  * attribute is still left for other arches.
28  */
29 struct attribute {
30 	const char		*name;
31 	struct module		*owner;
32 	mode_t			mode;
33 #ifdef CONFIG_DEBUG_LOCK_ALLOC
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 struct attribute_group {
61 	const char		*name;
62 	mode_t			(*is_visible)(struct kobject *,
63 					      struct attribute *, int);
64 	struct attribute	**attrs;
65 };
66 
67 
68 
69 /**
70  * Use these macros to make defining attributes easier. See include/linux/device.h
71  * for examples..
72  */
73 
74 #define __ATTR(_name,_mode,_show,_store) { \
75 	.attr = {.name = __stringify(_name), .mode = _mode },	\
76 	.show	= _show,					\
77 	.store	= _store,					\
78 }
79 
80 #define __ATTR_RO(_name) { \
81 	.attr	= { .name = __stringify(_name), .mode = 0444 },	\
82 	.show	= _name##_show,					\
83 }
84 
85 #define __ATTR_NULL { .attr = { .name = NULL } }
86 
87 #define attr_name(_attr) (_attr).attr.name
88 
89 struct vm_area_struct;
90 
91 struct bin_attribute {
92 	struct attribute	attr;
93 	size_t			size;
94 	void			*private;
95 	ssize_t (*read)(struct kobject *, struct bin_attribute *,
96 			char *, loff_t, size_t);
97 	ssize_t (*write)(struct kobject *, struct bin_attribute *,
98 			 char *, loff_t, size_t);
99 	int (*mmap)(struct kobject *, struct bin_attribute *attr,
100 		    struct vm_area_struct *vma);
101 };
102 
103 /**
104  *	sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
105  *	@attr: struct bin_attribute to initialize
106  *
107  *	Initialize a dynamically allocated struct bin_attribute so we
108  *	can make lockdep happy.  This is a new requirement for
109  *	attributes and initially this is only needed when lockdep is
110  *	enabled.  Lockdep gives a nice error when your attribute is
111  *	added to sysfs if you don't have this.
112  */
113 #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
114 
115 struct sysfs_ops {
116 	ssize_t	(*show)(struct kobject *, struct attribute *,char *);
117 	ssize_t	(*store)(struct kobject *,struct attribute *,const char *, size_t);
118 };
119 
120 struct sysfs_dirent;
121 
122 #ifdef CONFIG_SYSFS
123 
124 int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
125 			    void *data, struct module *owner);
126 
127 int __must_check sysfs_create_dir(struct kobject *kobj);
128 void sysfs_remove_dir(struct kobject *kobj);
129 int __must_check sysfs_rename_dir(struct kobject *kobj, const char *new_name);
130 int __must_check sysfs_move_dir(struct kobject *kobj,
131 				struct kobject *new_parent_kobj);
132 
133 int __must_check sysfs_create_file(struct kobject *kobj,
134 				   const struct attribute *attr);
135 int __must_check sysfs_create_files(struct kobject *kobj,
136 				   const struct attribute **attr);
137 int __must_check sysfs_chmod_file(struct kobject *kobj, struct attribute *attr,
138 				  mode_t mode);
139 void sysfs_remove_file(struct kobject *kobj, const struct attribute *attr);
140 void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
141 
142 int __must_check sysfs_create_bin_file(struct kobject *kobj,
143 				       const struct bin_attribute *attr);
144 void sysfs_remove_bin_file(struct kobject *kobj,
145 			   const struct bin_attribute *attr);
146 
147 int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
148 				   const char *name);
149 int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
150 					  struct kobject *target,
151 					  const char *name);
152 void sysfs_remove_link(struct kobject *kobj, const char *name);
153 
154 int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
155 			const char *old_name, const char *new_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 unsigned char *name);
172 struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd);
173 void sysfs_put(struct sysfs_dirent *sd);
174 void sysfs_printk_last_file(void);
175 int __must_check sysfs_init(void);
176 
177 #else /* CONFIG_SYSFS */
178 
179 static inline int sysfs_schedule_callback(struct kobject *kobj,
180 		void (*func)(void *), void *data, struct module *owner)
181 {
182 	return -ENOSYS;
183 }
184 
185 static inline int sysfs_create_dir(struct kobject *kobj)
186 {
187 	return 0;
188 }
189 
190 static inline void sysfs_remove_dir(struct kobject *kobj)
191 {
192 }
193 
194 static inline int sysfs_rename_dir(struct kobject *kobj, const char *new_name)
195 {
196 	return 0;
197 }
198 
199 static inline int sysfs_move_dir(struct kobject *kobj,
200 				 struct kobject *new_parent_kobj)
201 {
202 	return 0;
203 }
204 
205 static inline int sysfs_create_file(struct kobject *kobj,
206 				    const struct attribute *attr)
207 {
208 	return 0;
209 }
210 
211 static inline int sysfs_create_files(struct kobject *kobj,
212 				    const struct attribute **attr)
213 {
214 	return 0;
215 }
216 
217 static inline int sysfs_chmod_file(struct kobject *kobj,
218 				   struct attribute *attr, mode_t mode)
219 {
220 	return 0;
221 }
222 
223 static inline void sysfs_remove_file(struct kobject *kobj,
224 				     const struct attribute *attr)
225 {
226 }
227 
228 static inline void sysfs_remove_files(struct kobject *kobj,
229 				     const struct attribute **attr)
230 {
231 }
232 
233 static inline int sysfs_create_bin_file(struct kobject *kobj,
234 					const struct bin_attribute *attr)
235 {
236 	return 0;
237 }
238 
239 static inline void sysfs_remove_bin_file(struct kobject *kobj,
240 					 const struct bin_attribute *attr)
241 {
242 }
243 
244 static inline int sysfs_create_link(struct kobject *kobj,
245 				    struct kobject *target, const char *name)
246 {
247 	return 0;
248 }
249 
250 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
251 					   struct kobject *target,
252 					   const char *name)
253 {
254 	return 0;
255 }
256 
257 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
258 {
259 }
260 
261 static inline int sysfs_rename_link(struct kobject *k, struct kobject *t,
262 				    const char *old_name, const char *new_name)
263 {
264 	return 0;
265 }
266 
267 static inline int sysfs_create_group(struct kobject *kobj,
268 				     const struct attribute_group *grp)
269 {
270 	return 0;
271 }
272 
273 static inline int sysfs_update_group(struct kobject *kobj,
274 				const struct attribute_group *grp)
275 {
276 	return 0;
277 }
278 
279 static inline void sysfs_remove_group(struct kobject *kobj,
280 				      const struct attribute_group *grp)
281 {
282 }
283 
284 static inline int sysfs_add_file_to_group(struct kobject *kobj,
285 		const struct attribute *attr, const char *group)
286 {
287 	return 0;
288 }
289 
290 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
291 		const struct attribute *attr, const char *group)
292 {
293 }
294 
295 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
296 				const char *attr)
297 {
298 }
299 static inline void sysfs_notify_dirent(struct sysfs_dirent *sd)
300 {
301 }
302 static inline
303 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
304 				      const unsigned char *name)
305 {
306 	return NULL;
307 }
308 static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd)
309 {
310 	return NULL;
311 }
312 static inline void sysfs_put(struct sysfs_dirent *sd)
313 {
314 }
315 
316 static inline int __must_check sysfs_init(void)
317 {
318 	return 0;
319 }
320 
321 static inline void sysfs_printk_last_file(void)
322 {
323 }
324 
325 #endif /* CONFIG_SYSFS */
326 
327 #endif /* _SYSFS_H_ */
328