xref: /linux-6.15/include/linux/sysfs.h (revision 6fa79bca)
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 <linux/atomic.h>
21 
22 struct kobject;
23 struct module;
24 enum kobj_ns_type;
25 
26 struct attribute {
27 	const char		*name;
28 	umode_t			mode;
29 #ifdef CONFIG_DEBUG_LOCK_ALLOC
30 	bool			ignore_lockdep:1;
31 	struct lock_class_key	*key;
32 	struct lock_class_key	skey;
33 #endif
34 };
35 
36 /**
37  *	sysfs_attr_init - initialize a dynamically allocated sysfs attribute
38  *	@attr: struct attribute to initialize
39  *
40  *	Initialize a dynamically allocated struct attribute so we can
41  *	make lockdep happy.  This is a new requirement for attributes
42  *	and initially this is only needed when lockdep is enabled.
43  *	Lockdep gives a nice error when your attribute is added to
44  *	sysfs if you don't have this.
45  */
46 #ifdef CONFIG_DEBUG_LOCK_ALLOC
47 #define sysfs_attr_init(attr)				\
48 do {							\
49 	static struct lock_class_key __key;		\
50 							\
51 	(attr)->key = &__key;				\
52 } while(0)
53 #else
54 #define sysfs_attr_init(attr) do {} while(0)
55 #endif
56 
57 struct attribute_group {
58 	const char		*name;
59 	umode_t			(*is_visible)(struct kobject *,
60 					      struct attribute *, int);
61 	struct attribute	**attrs;
62 };
63 
64 
65 
66 /**
67  * Use these macros to make defining attributes easier. See include/linux/device.h
68  * for examples..
69  */
70 
71 #define __ATTR(_name,_mode,_show,_store) { \
72 	.attr = {.name = __stringify(_name), .mode = _mode },	\
73 	.show	= _show,					\
74 	.store	= _store,					\
75 }
76 
77 #define __ATTR_RO(_name) { \
78 	.attr	= { .name = __stringify(_name), .mode = 0444 },	\
79 	.show	= _name##_show,					\
80 }
81 
82 #define __ATTR_NULL { .attr = { .name = NULL } }
83 
84 #ifdef CONFIG_DEBUG_LOCK_ALLOC
85 #define __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) {	\
86 	.attr = {.name = __stringify(_name), .mode = _mode,	\
87 			.ignore_lockdep = true },		\
88 	.show		= _show,				\
89 	.store		= _store,				\
90 }
91 #else
92 #define __ATTR_IGNORE_LOCKDEP	__ATTR
93 #endif
94 
95 #define attr_name(_attr) (_attr).attr.name
96 
97 struct file;
98 struct vm_area_struct;
99 
100 struct bin_attribute {
101 	struct attribute	attr;
102 	size_t			size;
103 	void			*private;
104 	ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *,
105 			char *, loff_t, size_t);
106 	ssize_t (*write)(struct file *,struct kobject *, struct bin_attribute *,
107 			 char *, loff_t, size_t);
108 	int (*mmap)(struct file *, struct kobject *, struct bin_attribute *attr,
109 		    struct vm_area_struct *vma);
110 };
111 
112 /**
113  *	sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
114  *	@attr: struct bin_attribute to initialize
115  *
116  *	Initialize a dynamically allocated struct bin_attribute so we
117  *	can make lockdep happy.  This is a new requirement for
118  *	attributes and initially this is only needed when lockdep is
119  *	enabled.  Lockdep gives a nice error when your attribute is
120  *	added to sysfs if you don't have this.
121  */
122 #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
123 
124 struct sysfs_ops {
125 	ssize_t	(*show)(struct kobject *, struct attribute *,char *);
126 	ssize_t	(*store)(struct kobject *,struct attribute *,const char *, size_t);
127 	const void *(*namespace)(struct kobject *, const struct attribute *);
128 };
129 
130 struct sysfs_dirent;
131 
132 #ifdef CONFIG_SYSFS
133 
134 int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
135 			    void *data, struct module *owner);
136 
137 int __must_check sysfs_create_dir(struct kobject *kobj);
138 void sysfs_remove_dir(struct kobject *kobj);
139 int __must_check sysfs_rename_dir(struct kobject *kobj, const char *new_name);
140 int __must_check sysfs_move_dir(struct kobject *kobj,
141 				struct kobject *new_parent_kobj);
142 
143 int __must_check sysfs_create_file(struct kobject *kobj,
144 				   const struct attribute *attr);
145 int __must_check sysfs_create_files(struct kobject *kobj,
146 				   const struct attribute **attr);
147 int __must_check sysfs_chmod_file(struct kobject *kobj,
148 				  const struct attribute *attr, umode_t mode);
149 void sysfs_remove_file(struct kobject *kobj, const struct attribute *attr);
150 void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
151 
152 int __must_check sysfs_create_bin_file(struct kobject *kobj,
153 				       const struct bin_attribute *attr);
154 void sysfs_remove_bin_file(struct kobject *kobj,
155 			   const struct bin_attribute *attr);
156 
157 int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
158 				   const char *name);
159 int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
160 					  struct kobject *target,
161 					  const char *name);
162 void sysfs_remove_link(struct kobject *kobj, const char *name);
163 
164 int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
165 			const char *old_name, const char *new_name);
166 
167 void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
168 			const char *name);
169 
170 int __must_check sysfs_create_group(struct kobject *kobj,
171 				    const struct attribute_group *grp);
172 int sysfs_update_group(struct kobject *kobj,
173 		       const struct attribute_group *grp);
174 void sysfs_remove_group(struct kobject *kobj,
175 			const struct attribute_group *grp);
176 int sysfs_add_file_to_group(struct kobject *kobj,
177 			const struct attribute *attr, const char *group);
178 void sysfs_remove_file_from_group(struct kobject *kobj,
179 			const struct attribute *attr, const char *group);
180 int sysfs_merge_group(struct kobject *kobj,
181 		       const struct attribute_group *grp);
182 void sysfs_unmerge_group(struct kobject *kobj,
183 		       const struct attribute_group *grp);
184 
185 void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
186 void sysfs_notify_dirent(struct sysfs_dirent *sd);
187 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
188 				      const void *ns,
189 				      const unsigned char *name);
190 struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd);
191 void sysfs_put(struct sysfs_dirent *sd);
192 
193 int __must_check sysfs_init(void);
194 
195 #else /* CONFIG_SYSFS */
196 
197 static inline int sysfs_schedule_callback(struct kobject *kobj,
198 		void (*func)(void *), void *data, struct module *owner)
199 {
200 	return -ENOSYS;
201 }
202 
203 static inline int sysfs_create_dir(struct kobject *kobj)
204 {
205 	return 0;
206 }
207 
208 static inline void sysfs_remove_dir(struct kobject *kobj)
209 {
210 }
211 
212 static inline int sysfs_rename_dir(struct kobject *kobj, const char *new_name)
213 {
214 	return 0;
215 }
216 
217 static inline int sysfs_move_dir(struct kobject *kobj,
218 				 struct kobject *new_parent_kobj)
219 {
220 	return 0;
221 }
222 
223 static inline int sysfs_create_file(struct kobject *kobj,
224 				    const struct attribute *attr)
225 {
226 	return 0;
227 }
228 
229 static inline int sysfs_create_files(struct kobject *kobj,
230 				    const struct attribute **attr)
231 {
232 	return 0;
233 }
234 
235 static inline int sysfs_chmod_file(struct kobject *kobj,
236 				   const struct attribute *attr, umode_t mode)
237 {
238 	return 0;
239 }
240 
241 static inline void sysfs_remove_file(struct kobject *kobj,
242 				     const struct attribute *attr)
243 {
244 }
245 
246 static inline void sysfs_remove_files(struct kobject *kobj,
247 				     const struct attribute **attr)
248 {
249 }
250 
251 static inline int sysfs_create_bin_file(struct kobject *kobj,
252 					const struct bin_attribute *attr)
253 {
254 	return 0;
255 }
256 
257 static inline void sysfs_remove_bin_file(struct kobject *kobj,
258 					 const struct bin_attribute *attr)
259 {
260 }
261 
262 static inline int sysfs_create_link(struct kobject *kobj,
263 				    struct kobject *target, const char *name)
264 {
265 	return 0;
266 }
267 
268 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
269 					   struct kobject *target,
270 					   const char *name)
271 {
272 	return 0;
273 }
274 
275 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
276 {
277 }
278 
279 static inline int sysfs_rename_link(struct kobject *k, struct kobject *t,
280 				    const char *old_name, const char *new_name)
281 {
282 	return 0;
283 }
284 
285 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
286 				     const char *name)
287 {
288 }
289 
290 static inline int sysfs_create_group(struct kobject *kobj,
291 				     const struct attribute_group *grp)
292 {
293 	return 0;
294 }
295 
296 static inline int sysfs_update_group(struct kobject *kobj,
297 				const struct attribute_group *grp)
298 {
299 	return 0;
300 }
301 
302 static inline void sysfs_remove_group(struct kobject *kobj,
303 				      const struct attribute_group *grp)
304 {
305 }
306 
307 static inline int sysfs_add_file_to_group(struct kobject *kobj,
308 		const struct attribute *attr, const char *group)
309 {
310 	return 0;
311 }
312 
313 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
314 		const struct attribute *attr, const char *group)
315 {
316 }
317 
318 static inline int sysfs_merge_group(struct kobject *kobj,
319 		       const struct attribute_group *grp)
320 {
321 	return 0;
322 }
323 
324 static inline void sysfs_unmerge_group(struct kobject *kobj,
325 		       const struct attribute_group *grp)
326 {
327 }
328 
329 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
330 				const char *attr)
331 {
332 }
333 static inline void sysfs_notify_dirent(struct sysfs_dirent *sd)
334 {
335 }
336 static inline
337 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
338 				      const void *ns,
339 				      const unsigned char *name)
340 {
341 	return NULL;
342 }
343 static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd)
344 {
345 	return NULL;
346 }
347 static inline void sysfs_put(struct sysfs_dirent *sd)
348 {
349 }
350 
351 static inline int __must_check sysfs_init(void)
352 {
353 	return 0;
354 }
355 
356 #endif /* CONFIG_SYSFS */
357 
358 #endif /* _SYSFS_H_ */
359