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/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 void sysfs_printk_last_file(void);
180 
181 /* Called to clear a ns tag when it is no longer valid */
182 void sysfs_exit_ns(enum kobj_ns_type type, const void *tag);
183 
184 int __must_check sysfs_init(void);
185 
186 #else /* CONFIG_SYSFS */
187 
sysfs_schedule_callback(struct kobject * kobj,void (* func)(void *),void * data,struct module * owner)188 static inline int sysfs_schedule_callback(struct kobject *kobj,
189 		void (*func)(void *), void *data, struct module *owner)
190 {
191 	return -ENOSYS;
192 }
193 
sysfs_create_dir(struct kobject * kobj)194 static inline int sysfs_create_dir(struct kobject *kobj)
195 {
196 	return 0;
197 }
198 
sysfs_remove_dir(struct kobject * kobj)199 static inline void sysfs_remove_dir(struct kobject *kobj)
200 {
201 }
202 
sysfs_rename_dir(struct kobject * kobj,const char * new_name)203 static inline int sysfs_rename_dir(struct kobject *kobj, const char *new_name)
204 {
205 	return 0;
206 }
207 
sysfs_move_dir(struct kobject * kobj,struct kobject * new_parent_kobj)208 static inline int sysfs_move_dir(struct kobject *kobj,
209 				 struct kobject *new_parent_kobj)
210 {
211 	return 0;
212 }
213 
sysfs_create_file(struct kobject * kobj,const struct attribute * attr)214 static inline int sysfs_create_file(struct kobject *kobj,
215 				    const struct attribute *attr)
216 {
217 	return 0;
218 }
219 
sysfs_create_files(struct kobject * kobj,const struct attribute ** attr)220 static inline int sysfs_create_files(struct kobject *kobj,
221 				    const struct attribute **attr)
222 {
223 	return 0;
224 }
225 
sysfs_chmod_file(struct kobject * kobj,const struct attribute * attr,mode_t mode)226 static inline int sysfs_chmod_file(struct kobject *kobj,
227 				   const struct attribute *attr, mode_t mode)
228 {
229 	return 0;
230 }
231 
sysfs_remove_file(struct kobject * kobj,const struct attribute * attr)232 static inline void sysfs_remove_file(struct kobject *kobj,
233 				     const struct attribute *attr)
234 {
235 }
236 
sysfs_remove_files(struct kobject * kobj,const struct attribute ** attr)237 static inline void sysfs_remove_files(struct kobject *kobj,
238 				     const struct attribute **attr)
239 {
240 }
241 
sysfs_create_bin_file(struct kobject * kobj,const struct bin_attribute * attr)242 static inline int sysfs_create_bin_file(struct kobject *kobj,
243 					const struct bin_attribute *attr)
244 {
245 	return 0;
246 }
247 
sysfs_remove_bin_file(struct kobject * kobj,const struct bin_attribute * attr)248 static inline void sysfs_remove_bin_file(struct kobject *kobj,
249 					 const struct bin_attribute *attr)
250 {
251 }
252 
sysfs_create_link(struct kobject * kobj,struct kobject * target,const char * name)253 static inline int sysfs_create_link(struct kobject *kobj,
254 				    struct kobject *target, const char *name)
255 {
256 	return 0;
257 }
258 
sysfs_create_link_nowarn(struct kobject * kobj,struct kobject * target,const char * name)259 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
260 					   struct kobject *target,
261 					   const char *name)
262 {
263 	return 0;
264 }
265 
sysfs_remove_link(struct kobject * kobj,const char * name)266 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
267 {
268 }
269 
sysfs_rename_link(struct kobject * k,struct kobject * t,const char * old_name,const char * new_name)270 static inline int sysfs_rename_link(struct kobject *k, struct kobject *t,
271 				    const char *old_name, const char *new_name)
272 {
273 	return 0;
274 }
275 
sysfs_delete_link(struct kobject * k,struct kobject * t,const char * name)276 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
277 				     const char *name)
278 {
279 }
280 
sysfs_create_group(struct kobject * kobj,const struct attribute_group * grp)281 static inline int sysfs_create_group(struct kobject *kobj,
282 				     const struct attribute_group *grp)
283 {
284 	return 0;
285 }
286 
sysfs_update_group(struct kobject * kobj,const struct attribute_group * grp)287 static inline int sysfs_update_group(struct kobject *kobj,
288 				const struct attribute_group *grp)
289 {
290 	return 0;
291 }
292 
sysfs_remove_group(struct kobject * kobj,const struct attribute_group * grp)293 static inline void sysfs_remove_group(struct kobject *kobj,
294 				      const struct attribute_group *grp)
295 {
296 }
297 
sysfs_add_file_to_group(struct kobject * kobj,const struct attribute * attr,const char * group)298 static inline int sysfs_add_file_to_group(struct kobject *kobj,
299 		const struct attribute *attr, const char *group)
300 {
301 	return 0;
302 }
303 
sysfs_remove_file_from_group(struct kobject * kobj,const struct attribute * attr,const char * group)304 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
305 		const struct attribute *attr, const char *group)
306 {
307 }
308 
sysfs_merge_group(struct kobject * kobj,const struct attribute_group * grp)309 static inline int sysfs_merge_group(struct kobject *kobj,
310 		       const struct attribute_group *grp)
311 {
312 	return 0;
313 }
314 
sysfs_unmerge_group(struct kobject * kobj,const struct attribute_group * grp)315 static inline void sysfs_unmerge_group(struct kobject *kobj,
316 		       const struct attribute_group *grp)
317 {
318 }
319 
sysfs_notify(struct kobject * kobj,const char * dir,const char * attr)320 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
321 				const char *attr)
322 {
323 }
sysfs_notify_dirent(struct sysfs_dirent * sd)324 static inline void sysfs_notify_dirent(struct sysfs_dirent *sd)
325 {
326 }
327 static inline
sysfs_get_dirent(struct sysfs_dirent * parent_sd,const void * ns,const unsigned char * name)328 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
329 				      const void *ns,
330 				      const unsigned char *name)
331 {
332 	return NULL;
333 }
sysfs_get(struct sysfs_dirent * sd)334 static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd)
335 {
336 	return NULL;
337 }
sysfs_put(struct sysfs_dirent * sd)338 static inline void sysfs_put(struct sysfs_dirent *sd)
339 {
340 }
341 
sysfs_exit_ns(int type,const void * tag)342 static inline void sysfs_exit_ns(int type, const void *tag)
343 {
344 }
345 
sysfs_init(void)346 static inline int __must_check sysfs_init(void)
347 {
348 	return 0;
349 }
350 
sysfs_printk_last_file(void)351 static inline void sysfs_printk_last_file(void)
352 {
353 }
354 
355 #endif /* CONFIG_SYSFS */
356 
357 #endif /* _SYSFS_H_ */
358