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/kernfs.h>
16 #include <linux/compiler.h>
17 #include <linux/errno.h>
18 #include <linux/list.h>
19 #include <linux/lockdep.h>
20 #include <linux/kobject_ns.h>
21 #include <linux/stat.h>
22 #include <linux/atomic.h>
23
24 struct kobject;
25 struct module;
26 struct bin_attribute;
27 enum kobj_ns_type;
28
29 struct attribute {
30 const char *name;
31 umode_t mode;
32 #ifdef CONFIG_DEBUG_LOCK_ALLOC
33 bool ignore_lockdep:1;
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 /**
61 * struct attribute_group - data structure used to declare an attribute group.
62 * @name: Optional: Attribute group name
63 * If specified, the attribute group will be created in
64 * a new subdirectory with this name.
65 * @is_visible: Optional: Function to return permissions associated with an
66 * attribute of the group. Will be called repeatedly for each
67 * non-binary attribute in the group. Only read/write
68 * permissions as well as SYSFS_PREALLOC are accepted. Must
69 * return 0 if an attribute is not visible. The returned value
70 * will replace static permissions defined in struct attribute.
71 * @is_bin_visible:
72 * Optional: Function to return permissions associated with a
73 * binary attribute of the group. Will be called repeatedly
74 * for each binary attribute in the group. Only read/write
75 * permissions as well as SYSFS_PREALLOC are accepted. Must
76 * return 0 if a binary attribute is not visible. The returned
77 * value will replace static permissions defined in
78 * struct bin_attribute.
79 * @attrs: Pointer to NULL terminated list of attributes.
80 * @bin_attrs: Pointer to NULL terminated list of binary attributes.
81 * Either attrs or bin_attrs or both must be provided.
82 */
83 struct attribute_group {
84 const char *name;
85 umode_t (*is_visible)(struct kobject *,
86 struct attribute *, int);
87 umode_t (*is_bin_visible)(struct kobject *,
88 struct bin_attribute *, int);
89 struct attribute **attrs;
90 struct bin_attribute **bin_attrs;
91 };
92
93 /**
94 * Use these macros to make defining attributes easier. See include/linux/device.h
95 * for examples..
96 */
97
98 #define SYSFS_PREALLOC 010000
99
100 #define __ATTR(_name, _mode, _show, _store) { \
101 .attr = {.name = __stringify(_name), \
102 .mode = VERIFY_OCTAL_PERMISSIONS(_mode) }, \
103 .show = _show, \
104 .store = _store, \
105 }
106
107 #define __ATTR_PREALLOC(_name, _mode, _show, _store) { \
108 .attr = {.name = __stringify(_name), \
109 .mode = SYSFS_PREALLOC | VERIFY_OCTAL_PERMISSIONS(_mode) },\
110 .show = _show, \
111 .store = _store, \
112 }
113
114 #define __ATTR_RO(_name) { \
115 .attr = { .name = __stringify(_name), .mode = S_IRUGO }, \
116 .show = _name##_show, \
117 }
118
119 #define __ATTR_RO_MODE(_name, _mode) { \
120 .attr = { .name = __stringify(_name), \
121 .mode = VERIFY_OCTAL_PERMISSIONS(_mode) }, \
122 .show = _name##_show, \
123 }
124
125 #define __ATTR_WO(_name) { \
126 .attr = { .name = __stringify(_name), .mode = S_IWUSR }, \
127 .store = _name##_store, \
128 }
129
130 #define __ATTR_RW(_name) __ATTR(_name, (S_IWUSR | S_IRUGO), \
131 _name##_show, _name##_store)
132
133 #define __ATTR_NULL { .attr = { .name = NULL } }
134
135 #ifdef CONFIG_DEBUG_LOCK_ALLOC
136 #define __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) { \
137 .attr = {.name = __stringify(_name), .mode = _mode, \
138 .ignore_lockdep = true }, \
139 .show = _show, \
140 .store = _store, \
141 }
142 #else
143 #define __ATTR_IGNORE_LOCKDEP __ATTR
144 #endif
145
146 #define __ATTRIBUTE_GROUPS(_name) \
147 static const struct attribute_group *_name##_groups[] = { \
148 &_name##_group, \
149 NULL, \
150 }
151
152 #define ATTRIBUTE_GROUPS(_name) \
153 static const struct attribute_group _name##_group = { \
154 .attrs = _name##_attrs, \
155 }; \
156 __ATTRIBUTE_GROUPS(_name)
157
158 struct file;
159 struct vm_area_struct;
160
161 struct bin_attribute {
162 struct attribute attr;
163 size_t size;
164 void *private;
165 ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *,
166 char *, loff_t, size_t);
167 ssize_t (*write)(struct file *, struct kobject *, struct bin_attribute *,
168 char *, loff_t, size_t);
169 int (*mmap)(struct file *, struct kobject *, struct bin_attribute *attr,
170 struct vm_area_struct *vma);
171 };
172
173 /**
174 * sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
175 * @attr: struct bin_attribute to initialize
176 *
177 * Initialize a dynamically allocated struct bin_attribute so we
178 * can make lockdep happy. This is a new requirement for
179 * attributes and initially this is only needed when lockdep is
180 * enabled. Lockdep gives a nice error when your attribute is
181 * added to sysfs if you don't have this.
182 */
183 #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
184
185 /* macros to create static binary attributes easier */
186 #define __BIN_ATTR(_name, _mode, _read, _write, _size) { \
187 .attr = { .name = __stringify(_name), .mode = _mode }, \
188 .read = _read, \
189 .write = _write, \
190 .size = _size, \
191 }
192
193 #define __BIN_ATTR_RO(_name, _size) { \
194 .attr = { .name = __stringify(_name), .mode = S_IRUGO }, \
195 .read = _name##_read, \
196 .size = _size, \
197 }
198
199 #define __BIN_ATTR_RW(_name, _size) __BIN_ATTR(_name, \
200 (S_IWUSR | S_IRUGO), _name##_read, \
201 _name##_write, _size)
202
203 #define __BIN_ATTR_NULL __ATTR_NULL
204
205 #define BIN_ATTR(_name, _mode, _read, _write, _size) \
206 struct bin_attribute bin_attr_##_name = __BIN_ATTR(_name, _mode, _read, \
207 _write, _size)
208
209 #define BIN_ATTR_RO(_name, _size) \
210 struct bin_attribute bin_attr_##_name = __BIN_ATTR_RO(_name, _size)
211
212 #define BIN_ATTR_RW(_name, _size) \
213 struct bin_attribute bin_attr_##_name = __BIN_ATTR_RW(_name, _size)
214
215 struct sysfs_ops {
216 ssize_t (*show)(struct kobject *, struct attribute *, char *);
217 ssize_t (*store)(struct kobject *, struct attribute *, const char *, size_t);
218 };
219
220 #ifdef CONFIG_SYSFS
221
222 int __must_check sysfs_create_dir_ns(struct kobject *kobj, const void *ns);
223 void sysfs_remove_dir(struct kobject *kobj);
224 int __must_check sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name,
225 const void *new_ns);
226 int __must_check sysfs_move_dir_ns(struct kobject *kobj,
227 struct kobject *new_parent_kobj,
228 const void *new_ns);
229 int __must_check sysfs_create_mount_point(struct kobject *parent_kobj,
230 const char *name);
231 void sysfs_remove_mount_point(struct kobject *parent_kobj,
232 const char *name);
233
234 int __must_check sysfs_create_file_ns(struct kobject *kobj,
235 const struct attribute *attr,
236 const void *ns);
237 int __must_check sysfs_create_files(struct kobject *kobj,
238 const struct attribute **attr);
239 int __must_check sysfs_chmod_file(struct kobject *kobj,
240 const struct attribute *attr, umode_t mode);
241 void sysfs_remove_file_ns(struct kobject *kobj, const struct attribute *attr,
242 const void *ns);
243 bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr);
244 void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
245
246 int __must_check sysfs_create_bin_file(struct kobject *kobj,
247 const struct bin_attribute *attr);
248 void sysfs_remove_bin_file(struct kobject *kobj,
249 const struct bin_attribute *attr);
250
251 int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
252 const char *name);
253 int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
254 struct kobject *target,
255 const char *name);
256 void sysfs_remove_link(struct kobject *kobj, const char *name);
257
258 int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *target,
259 const char *old_name, const char *new_name,
260 const void *new_ns);
261
262 void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
263 const char *name);
264
265 int __must_check sysfs_create_group(struct kobject *kobj,
266 const struct attribute_group *grp);
267 int __must_check sysfs_create_groups(struct kobject *kobj,
268 const struct attribute_group **groups);
269 int sysfs_update_group(struct kobject *kobj,
270 const struct attribute_group *grp);
271 void sysfs_remove_group(struct kobject *kobj,
272 const struct attribute_group *grp);
273 void sysfs_remove_groups(struct kobject *kobj,
274 const struct attribute_group **groups);
275 int sysfs_add_file_to_group(struct kobject *kobj,
276 const struct attribute *attr, const char *group);
277 void sysfs_remove_file_from_group(struct kobject *kobj,
278 const struct attribute *attr, const char *group);
279 int sysfs_merge_group(struct kobject *kobj,
280 const struct attribute_group *grp);
281 void sysfs_unmerge_group(struct kobject *kobj,
282 const struct attribute_group *grp);
283 int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name,
284 struct kobject *target, const char *link_name);
285 void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
286 const char *link_name);
287 int __compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
288 struct kobject *target_kobj,
289 const char *target_name);
290
291 void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
292
293 int __must_check sysfs_init(void);
294
sysfs_enable_ns(struct kernfs_node * kn)295 static inline void sysfs_enable_ns(struct kernfs_node *kn)
296 {
297 return kernfs_enable_ns(kn);
298 }
299
300 #else /* CONFIG_SYSFS */
301
sysfs_create_dir_ns(struct kobject * kobj,const void * ns)302 static inline int sysfs_create_dir_ns(struct kobject *kobj, const void *ns)
303 {
304 return 0;
305 }
306
sysfs_remove_dir(struct kobject * kobj)307 static inline void sysfs_remove_dir(struct kobject *kobj)
308 {
309 }
310
sysfs_rename_dir_ns(struct kobject * kobj,const char * new_name,const void * new_ns)311 static inline int sysfs_rename_dir_ns(struct kobject *kobj,
312 const char *new_name, const void *new_ns)
313 {
314 return 0;
315 }
316
sysfs_move_dir_ns(struct kobject * kobj,struct kobject * new_parent_kobj,const void * new_ns)317 static inline int sysfs_move_dir_ns(struct kobject *kobj,
318 struct kobject *new_parent_kobj,
319 const void *new_ns)
320 {
321 return 0;
322 }
323
sysfs_create_mount_point(struct kobject * parent_kobj,const char * name)324 static inline int sysfs_create_mount_point(struct kobject *parent_kobj,
325 const char *name)
326 {
327 return 0;
328 }
329
sysfs_remove_mount_point(struct kobject * parent_kobj,const char * name)330 static inline void sysfs_remove_mount_point(struct kobject *parent_kobj,
331 const char *name)
332 {
333 }
334
sysfs_create_file_ns(struct kobject * kobj,const struct attribute * attr,const void * ns)335 static inline int sysfs_create_file_ns(struct kobject *kobj,
336 const struct attribute *attr,
337 const void *ns)
338 {
339 return 0;
340 }
341
sysfs_create_files(struct kobject * kobj,const struct attribute ** attr)342 static inline int sysfs_create_files(struct kobject *kobj,
343 const struct attribute **attr)
344 {
345 return 0;
346 }
347
sysfs_chmod_file(struct kobject * kobj,const struct attribute * attr,umode_t mode)348 static inline int sysfs_chmod_file(struct kobject *kobj,
349 const struct attribute *attr, umode_t mode)
350 {
351 return 0;
352 }
353
sysfs_remove_file_ns(struct kobject * kobj,const struct attribute * attr,const void * ns)354 static inline void sysfs_remove_file_ns(struct kobject *kobj,
355 const struct attribute *attr,
356 const void *ns)
357 {
358 }
359
sysfs_remove_file_self(struct kobject * kobj,const struct attribute * attr)360 static inline bool sysfs_remove_file_self(struct kobject *kobj,
361 const struct attribute *attr)
362 {
363 return false;
364 }
365
sysfs_remove_files(struct kobject * kobj,const struct attribute ** attr)366 static inline void sysfs_remove_files(struct kobject *kobj,
367 const struct attribute **attr)
368 {
369 }
370
sysfs_create_bin_file(struct kobject * kobj,const struct bin_attribute * attr)371 static inline int sysfs_create_bin_file(struct kobject *kobj,
372 const struct bin_attribute *attr)
373 {
374 return 0;
375 }
376
sysfs_remove_bin_file(struct kobject * kobj,const struct bin_attribute * attr)377 static inline void sysfs_remove_bin_file(struct kobject *kobj,
378 const struct bin_attribute *attr)
379 {
380 }
381
sysfs_create_link(struct kobject * kobj,struct kobject * target,const char * name)382 static inline int sysfs_create_link(struct kobject *kobj,
383 struct kobject *target, const char *name)
384 {
385 return 0;
386 }
387
sysfs_create_link_nowarn(struct kobject * kobj,struct kobject * target,const char * name)388 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
389 struct kobject *target,
390 const char *name)
391 {
392 return 0;
393 }
394
sysfs_remove_link(struct kobject * kobj,const char * name)395 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
396 {
397 }
398
sysfs_rename_link_ns(struct kobject * k,struct kobject * t,const char * old_name,const char * new_name,const void * ns)399 static inline int sysfs_rename_link_ns(struct kobject *k, struct kobject *t,
400 const char *old_name,
401 const char *new_name, const void *ns)
402 {
403 return 0;
404 }
405
sysfs_delete_link(struct kobject * k,struct kobject * t,const char * name)406 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
407 const char *name)
408 {
409 }
410
sysfs_create_group(struct kobject * kobj,const struct attribute_group * grp)411 static inline int sysfs_create_group(struct kobject *kobj,
412 const struct attribute_group *grp)
413 {
414 return 0;
415 }
416
sysfs_create_groups(struct kobject * kobj,const struct attribute_group ** groups)417 static inline int sysfs_create_groups(struct kobject *kobj,
418 const struct attribute_group **groups)
419 {
420 return 0;
421 }
422
sysfs_update_group(struct kobject * kobj,const struct attribute_group * grp)423 static inline int sysfs_update_group(struct kobject *kobj,
424 const struct attribute_group *grp)
425 {
426 return 0;
427 }
428
sysfs_remove_group(struct kobject * kobj,const struct attribute_group * grp)429 static inline void sysfs_remove_group(struct kobject *kobj,
430 const struct attribute_group *grp)
431 {
432 }
433
sysfs_remove_groups(struct kobject * kobj,const struct attribute_group ** groups)434 static inline void sysfs_remove_groups(struct kobject *kobj,
435 const struct attribute_group **groups)
436 {
437 }
438
sysfs_add_file_to_group(struct kobject * kobj,const struct attribute * attr,const char * group)439 static inline int sysfs_add_file_to_group(struct kobject *kobj,
440 const struct attribute *attr, const char *group)
441 {
442 return 0;
443 }
444
sysfs_remove_file_from_group(struct kobject * kobj,const struct attribute * attr,const char * group)445 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
446 const struct attribute *attr, const char *group)
447 {
448 }
449
sysfs_merge_group(struct kobject * kobj,const struct attribute_group * grp)450 static inline int sysfs_merge_group(struct kobject *kobj,
451 const struct attribute_group *grp)
452 {
453 return 0;
454 }
455
sysfs_unmerge_group(struct kobject * kobj,const struct attribute_group * grp)456 static inline void sysfs_unmerge_group(struct kobject *kobj,
457 const struct attribute_group *grp)
458 {
459 }
460
sysfs_add_link_to_group(struct kobject * kobj,const char * group_name,struct kobject * target,const char * link_name)461 static inline int sysfs_add_link_to_group(struct kobject *kobj,
462 const char *group_name, struct kobject *target,
463 const char *link_name)
464 {
465 return 0;
466 }
467
sysfs_remove_link_from_group(struct kobject * kobj,const char * group_name,const char * link_name)468 static inline void sysfs_remove_link_from_group(struct kobject *kobj,
469 const char *group_name, const char *link_name)
470 {
471 }
472
__compat_only_sysfs_link_entry_to_kobj(struct kobject * kobj,struct kobject * target_kobj,const char * target_name)473 static inline int __compat_only_sysfs_link_entry_to_kobj(
474 struct kobject *kobj,
475 struct kobject *target_kobj,
476 const char *target_name)
477 {
478 return 0;
479 }
480
sysfs_notify(struct kobject * kobj,const char * dir,const char * attr)481 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
482 const char *attr)
483 {
484 }
485
sysfs_init(void)486 static inline int __must_check sysfs_init(void)
487 {
488 return 0;
489 }
490
sysfs_enable_ns(struct kernfs_node * kn)491 static inline void sysfs_enable_ns(struct kernfs_node *kn)
492 {
493 }
494
495 #endif /* CONFIG_SYSFS */
496
sysfs_create_file(struct kobject * kobj,const struct attribute * attr)497 static inline int __must_check sysfs_create_file(struct kobject *kobj,
498 const struct attribute *attr)
499 {
500 return sysfs_create_file_ns(kobj, attr, NULL);
501 }
502
sysfs_remove_file(struct kobject * kobj,const struct attribute * attr)503 static inline void sysfs_remove_file(struct kobject *kobj,
504 const struct attribute *attr)
505 {
506 sysfs_remove_file_ns(kobj, attr, NULL);
507 }
508
sysfs_rename_link(struct kobject * kobj,struct kobject * target,const char * old_name,const char * new_name)509 static inline int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
510 const char *old_name, const char *new_name)
511 {
512 return sysfs_rename_link_ns(kobj, target, old_name, new_name, NULL);
513 }
514
sysfs_notify_dirent(struct kernfs_node * kn)515 static inline void sysfs_notify_dirent(struct kernfs_node *kn)
516 {
517 kernfs_notify(kn);
518 }
519
sysfs_get_dirent(struct kernfs_node * parent,const unsigned char * name)520 static inline struct kernfs_node *sysfs_get_dirent(struct kernfs_node *parent,
521 const unsigned char *name)
522 {
523 return kernfs_find_and_get(parent, name);
524 }
525
sysfs_get(struct kernfs_node * kn)526 static inline struct kernfs_node *sysfs_get(struct kernfs_node *kn)
527 {
528 kernfs_get(kn);
529 return kn;
530 }
531
sysfs_put(struct kernfs_node * kn)532 static inline void sysfs_put(struct kernfs_node *kn)
533 {
534 kernfs_put(kn);
535 }
536
537 #endif /* _SYSFS_H_ */
538