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_WO(_name) { \
120 .attr = { .name = __stringify(_name), .mode = S_IWUSR }, \
121 .store = _name##_store, \
122 }
123
124 #define __ATTR_RW(_name) __ATTR(_name, (S_IWUSR | S_IRUGO), \
125 _name##_show, _name##_store)
126
127 #define __ATTR_NULL { .attr = { .name = NULL } }
128
129 #ifdef CONFIG_DEBUG_LOCK_ALLOC
130 #define __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) { \
131 .attr = {.name = __stringify(_name), .mode = _mode, \
132 .ignore_lockdep = true }, \
133 .show = _show, \
134 .store = _store, \
135 }
136 #else
137 #define __ATTR_IGNORE_LOCKDEP __ATTR
138 #endif
139
140 #define __ATTRIBUTE_GROUPS(_name) \
141 static const struct attribute_group *_name##_groups[] = { \
142 &_name##_group, \
143 NULL, \
144 }
145
146 #define ATTRIBUTE_GROUPS(_name) \
147 static const struct attribute_group _name##_group = { \
148 .attrs = _name##_attrs, \
149 }; \
150 __ATTRIBUTE_GROUPS(_name)
151
152 struct file;
153 struct vm_area_struct;
154
155 struct bin_attribute {
156 struct attribute attr;
157 size_t size;
158 void *private;
159 ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *,
160 char *, loff_t, size_t);
161 ssize_t (*write)(struct file *, struct kobject *, struct bin_attribute *,
162 char *, loff_t, size_t);
163 int (*mmap)(struct file *, struct kobject *, struct bin_attribute *attr,
164 struct vm_area_struct *vma);
165 };
166
167 /**
168 * sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
169 * @attr: struct bin_attribute to initialize
170 *
171 * Initialize a dynamically allocated struct bin_attribute so we
172 * can make lockdep happy. This is a new requirement for
173 * attributes and initially this is only needed when lockdep is
174 * enabled. Lockdep gives a nice error when your attribute is
175 * added to sysfs if you don't have this.
176 */
177 #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
178
179 /* macros to create static binary attributes easier */
180 #define __BIN_ATTR(_name, _mode, _read, _write, _size) { \
181 .attr = { .name = __stringify(_name), .mode = _mode }, \
182 .read = _read, \
183 .write = _write, \
184 .size = _size, \
185 }
186
187 #define __BIN_ATTR_RO(_name, _size) { \
188 .attr = { .name = __stringify(_name), .mode = S_IRUGO }, \
189 .read = _name##_read, \
190 .size = _size, \
191 }
192
193 #define __BIN_ATTR_RW(_name, _size) __BIN_ATTR(_name, \
194 (S_IWUSR | S_IRUGO), _name##_read, \
195 _name##_write, _size)
196
197 #define __BIN_ATTR_NULL __ATTR_NULL
198
199 #define BIN_ATTR(_name, _mode, _read, _write, _size) \
200 struct bin_attribute bin_attr_##_name = __BIN_ATTR(_name, _mode, _read, \
201 _write, _size)
202
203 #define BIN_ATTR_RO(_name, _size) \
204 struct bin_attribute bin_attr_##_name = __BIN_ATTR_RO(_name, _size)
205
206 #define BIN_ATTR_RW(_name, _size) \
207 struct bin_attribute bin_attr_##_name = __BIN_ATTR_RW(_name, _size)
208
209 struct sysfs_ops {
210 ssize_t (*show)(struct kobject *, struct attribute *, char *);
211 ssize_t (*store)(struct kobject *, struct attribute *, const char *, size_t);
212 };
213
214 #ifdef CONFIG_SYSFS
215
216 int __must_check sysfs_create_dir_ns(struct kobject *kobj, const void *ns);
217 void sysfs_remove_dir(struct kobject *kobj);
218 int __must_check sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name,
219 const void *new_ns);
220 int __must_check sysfs_move_dir_ns(struct kobject *kobj,
221 struct kobject *new_parent_kobj,
222 const void *new_ns);
223 int __must_check sysfs_create_mount_point(struct kobject *parent_kobj,
224 const char *name);
225 void sysfs_remove_mount_point(struct kobject *parent_kobj,
226 const char *name);
227
228 int __must_check sysfs_create_file_ns(struct kobject *kobj,
229 const struct attribute *attr,
230 const void *ns);
231 int __must_check sysfs_create_files(struct kobject *kobj,
232 const struct attribute **attr);
233 int __must_check sysfs_chmod_file(struct kobject *kobj,
234 const struct attribute *attr, umode_t mode);
235 void sysfs_remove_file_ns(struct kobject *kobj, const struct attribute *attr,
236 const void *ns);
237 bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr);
238 void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
239
240 int __must_check sysfs_create_bin_file(struct kobject *kobj,
241 const struct bin_attribute *attr);
242 void sysfs_remove_bin_file(struct kobject *kobj,
243 const struct bin_attribute *attr);
244
245 int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
246 const char *name);
247 int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
248 struct kobject *target,
249 const char *name);
250 void sysfs_remove_link(struct kobject *kobj, const char *name);
251
252 int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *target,
253 const char *old_name, const char *new_name,
254 const void *new_ns);
255
256 void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
257 const char *name);
258
259 int __must_check sysfs_create_group(struct kobject *kobj,
260 const struct attribute_group *grp);
261 int __must_check sysfs_create_groups(struct kobject *kobj,
262 const struct attribute_group **groups);
263 int sysfs_update_group(struct kobject *kobj,
264 const struct attribute_group *grp);
265 void sysfs_remove_group(struct kobject *kobj,
266 const struct attribute_group *grp);
267 void sysfs_remove_groups(struct kobject *kobj,
268 const struct attribute_group **groups);
269 int sysfs_add_file_to_group(struct kobject *kobj,
270 const struct attribute *attr, const char *group);
271 void sysfs_remove_file_from_group(struct kobject *kobj,
272 const struct attribute *attr, const char *group);
273 int sysfs_merge_group(struct kobject *kobj,
274 const struct attribute_group *grp);
275 void sysfs_unmerge_group(struct kobject *kobj,
276 const struct attribute_group *grp);
277 int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name,
278 struct kobject *target, const char *link_name);
279 void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
280 const char *link_name);
281 int __compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
282 struct kobject *target_kobj,
283 const char *target_name);
284
285 void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
286
287 int __must_check sysfs_init(void);
288
289 static inline void sysfs_enable_ns(struct kernfs_node *kn)
290 {
291 return kernfs_enable_ns(kn);
292 }
293
294 #else /* CONFIG_SYSFS */
295
296 static inline int sysfs_create_dir_ns(struct kobject *kobj, const void *ns)
297 {
298 return 0;
299 }
300
301 static inline void sysfs_remove_dir(struct kobject *kobj)
302 {
303 }
304
305 static inline int sysfs_rename_dir_ns(struct kobject *kobj,
306 const char *new_name, const void *new_ns)
307 {
308 return 0;
309 }
310
311 static inline int sysfs_move_dir_ns(struct kobject *kobj,
312 struct kobject *new_parent_kobj,
313 const void *new_ns)
314 {
315 return 0;
316 }
317
318 static inline int sysfs_create_mount_point(struct kobject *parent_kobj,
319 const char *name)
320 {
321 return 0;
322 }
323
324 static inline void sysfs_remove_mount_point(struct kobject *parent_kobj,
325 const char *name)
326 {
327 }
328
329 static inline int sysfs_create_file_ns(struct kobject *kobj,
330 const struct attribute *attr,
331 const void *ns)
332 {
333 return 0;
334 }
335
336 static inline int sysfs_create_files(struct kobject *kobj,
337 const struct attribute **attr)
338 {
339 return 0;
340 }
341
342 static inline int sysfs_chmod_file(struct kobject *kobj,
343 const struct attribute *attr, umode_t mode)
344 {
345 return 0;
346 }
347
348 static inline void sysfs_remove_file_ns(struct kobject *kobj,
349 const struct attribute *attr,
350 const void *ns)
351 {
352 }
353
354 static inline bool sysfs_remove_file_self(struct kobject *kobj,
355 const struct attribute *attr)
356 {
357 return false;
358 }
359
360 static inline void sysfs_remove_files(struct kobject *kobj,
361 const struct attribute **attr)
362 {
363 }
364
365 static inline int sysfs_create_bin_file(struct kobject *kobj,
366 const struct bin_attribute *attr)
367 {
368 return 0;
369 }
370
371 static inline void sysfs_remove_bin_file(struct kobject *kobj,
372 const struct bin_attribute *attr)
373 {
374 }
375
376 static inline int sysfs_create_link(struct kobject *kobj,
377 struct kobject *target, const char *name)
378 {
379 return 0;
380 }
381
382 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
383 struct kobject *target,
384 const char *name)
385 {
386 return 0;
387 }
388
389 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
390 {
391 }
392
393 static inline int sysfs_rename_link_ns(struct kobject *k, struct kobject *t,
394 const char *old_name,
395 const char *new_name, const void *ns)
396 {
397 return 0;
398 }
399
400 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
401 const char *name)
402 {
403 }
404
405 static inline int sysfs_create_group(struct kobject *kobj,
406 const struct attribute_group *grp)
407 {
408 return 0;
409 }
410
411 static inline int sysfs_create_groups(struct kobject *kobj,
412 const struct attribute_group **groups)
413 {
414 return 0;
415 }
416
417 static inline int sysfs_update_group(struct kobject *kobj,
418 const struct attribute_group *grp)
419 {
420 return 0;
421 }
422
423 static inline void sysfs_remove_group(struct kobject *kobj,
424 const struct attribute_group *grp)
425 {
426 }
427
428 static inline void sysfs_remove_groups(struct kobject *kobj,
429 const struct attribute_group **groups)
430 {
431 }
432
433 static inline int sysfs_add_file_to_group(struct kobject *kobj,
434 const struct attribute *attr, const char *group)
435 {
436 return 0;
437 }
438
439 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
440 const struct attribute *attr, const char *group)
441 {
442 }
443
444 static inline int sysfs_merge_group(struct kobject *kobj,
445 const struct attribute_group *grp)
446 {
447 return 0;
448 }
449
450 static inline void sysfs_unmerge_group(struct kobject *kobj,
451 const struct attribute_group *grp)
452 {
453 }
454
455 static inline int sysfs_add_link_to_group(struct kobject *kobj,
456 const char *group_name, struct kobject *target,
457 const char *link_name)
458 {
459 return 0;
460 }
461
462 static inline void sysfs_remove_link_from_group(struct kobject *kobj,
463 const char *group_name, const char *link_name)
464 {
465 }
466
467 static inline int __compat_only_sysfs_link_entry_to_kobj(
468 struct kobject *kobj,
469 struct kobject *target_kobj,
470 const char *target_name)
471 {
472 return 0;
473 }
474
475 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
476 const char *attr)
477 {
478 }
479
480 static inline int __must_check sysfs_init(void)
481 {
482 return 0;
483 }
484
485 static inline void sysfs_enable_ns(struct kernfs_node *kn)
486 {
487 }
488
489 #endif /* CONFIG_SYSFS */
490
491 static inline int __must_check sysfs_create_file(struct kobject *kobj,
492 const struct attribute *attr)
493 {
494 return sysfs_create_file_ns(kobj, attr, NULL);
495 }
496
497 static inline void sysfs_remove_file(struct kobject *kobj,
498 const struct attribute *attr)
499 {
500 sysfs_remove_file_ns(kobj, attr, NULL);
501 }
502
503 static inline int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
504 const char *old_name, const char *new_name)
505 {
506 return sysfs_rename_link_ns(kobj, target, old_name, new_name, NULL);
507 }
508
509 static inline void sysfs_notify_dirent(struct kernfs_node *kn)
510 {
511 kernfs_notify(kn);
512 }
513
514 static inline struct kernfs_node *sysfs_get_dirent(struct kernfs_node *parent,
515 const unsigned char *name)
516 {
517 return kernfs_find_and_get(parent, name);
518 }
519
520 static inline struct kernfs_node *sysfs_get(struct kernfs_node *kn)
521 {
522 kernfs_get(kn);
523 return kn;
524 }
525
526 static inline void sysfs_put(struct kernfs_node *kn)
527 {
528 kernfs_put(kn);
529 }
530
531 #endif /* _SYSFS_H_ */
532
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