Line data Source code
1 : /* SPDX-License-Identifier: GPL-2.0 */
2 : /*
3 : * sysfs.h - definitions for the device driver filesystem
4 : *
5 : * Copyright (c) 2001,2002 Patrick Mochel
6 : * Copyright (c) 2004 Silicon Graphics, Inc.
7 : * Copyright (c) 2007 SUSE Linux Products GmbH
8 : * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
9 : *
10 : * Please see Documentation/filesystems/sysfs.rst for more information.
11 : */
12 :
13 : #ifndef _SYSFS_H_
14 : #define _SYSFS_H_
15 :
16 : #include <linux/kernfs.h>
17 : #include <linux/compiler.h>
18 : #include <linux/errno.h>
19 : #include <linux/list.h>
20 : #include <linux/lockdep.h>
21 : #include <linux/kobject_ns.h>
22 : #include <linux/stat.h>
23 : #include <linux/atomic.h>
24 :
25 : struct kobject;
26 : struct module;
27 : struct bin_attribute;
28 : enum kobj_ns_type;
29 :
30 : struct attribute {
31 : const char *name;
32 : umode_t mode;
33 : #ifdef CONFIG_DEBUG_LOCK_ALLOC
34 : bool ignore_lockdep:1;
35 : struct lock_class_key *key;
36 : struct lock_class_key skey;
37 : #endif
38 : };
39 :
40 : /**
41 : * sysfs_attr_init - initialize a dynamically allocated sysfs attribute
42 : * @attr: struct attribute to initialize
43 : *
44 : * Initialize a dynamically allocated struct attribute so we can
45 : * make lockdep happy. This is a new requirement for attributes
46 : * and initially this is only needed when lockdep is enabled.
47 : * Lockdep gives a nice error when your attribute is added to
48 : * sysfs if you don't have this.
49 : */
50 : #ifdef CONFIG_DEBUG_LOCK_ALLOC
51 : #define sysfs_attr_init(attr) \
52 : do { \
53 : static struct lock_class_key __key; \
54 : \
55 : (attr)->key = &__key; \
56 : } while (0)
57 : #else
58 : #define sysfs_attr_init(attr) do {} while (0)
59 : #endif
60 :
61 : /**
62 : * struct attribute_group - data structure used to declare an attribute group.
63 : * @name: Optional: Attribute group name
64 : * If specified, the attribute group will be created in
65 : * a new subdirectory with this name.
66 : * @is_visible: Optional: Function to return permissions associated with an
67 : * attribute of the group. Will be called repeatedly for each
68 : * non-binary attribute in the group. Only read/write
69 : * permissions as well as SYSFS_PREALLOC are accepted. Must
70 : * return 0 if an attribute is not visible. The returned value
71 : * will replace static permissions defined in struct attribute.
72 : * @is_bin_visible:
73 : * Optional: Function to return permissions associated with a
74 : * binary attribute of the group. Will be called repeatedly
75 : * for each binary attribute in the group. Only read/write
76 : * permissions as well as SYSFS_PREALLOC are accepted. Must
77 : * return 0 if a binary attribute is not visible. The returned
78 : * value will replace static permissions defined in
79 : * struct bin_attribute.
80 : * @attrs: Pointer to NULL terminated list of attributes.
81 : * @bin_attrs: Pointer to NULL terminated list of binary attributes.
82 : * Either attrs or bin_attrs or both must be provided.
83 : */
84 : struct attribute_group {
85 : const char *name;
86 : umode_t (*is_visible)(struct kobject *,
87 : struct attribute *, int);
88 : umode_t (*is_bin_visible)(struct kobject *,
89 : struct bin_attribute *, int);
90 : struct attribute **attrs;
91 : struct bin_attribute **bin_attrs;
92 : };
93 :
94 : /*
95 : * Use these macros to make defining attributes easier.
96 : * See include/linux/device.h for examples..
97 : */
98 :
99 : #define SYSFS_PREALLOC 010000
100 :
101 : #define __ATTR(_name, _mode, _show, _store) { \
102 : .attr = {.name = __stringify(_name), \
103 : .mode = VERIFY_OCTAL_PERMISSIONS(_mode) }, \
104 : .show = _show, \
105 : .store = _store, \
106 : }
107 :
108 : #define __ATTR_PREALLOC(_name, _mode, _show, _store) { \
109 : .attr = {.name = __stringify(_name), \
110 : .mode = SYSFS_PREALLOC | VERIFY_OCTAL_PERMISSIONS(_mode) },\
111 : .show = _show, \
112 : .store = _store, \
113 : }
114 :
115 : #define __ATTR_RO(_name) { \
116 : .attr = { .name = __stringify(_name), .mode = 0444 }, \
117 : .show = _name##_show, \
118 : }
119 :
120 : #define __ATTR_RO_MODE(_name, _mode) { \
121 : .attr = { .name = __stringify(_name), \
122 : .mode = VERIFY_OCTAL_PERMISSIONS(_mode) }, \
123 : .show = _name##_show, \
124 : }
125 :
126 : #define __ATTR_RW_MODE(_name, _mode) { \
127 : .attr = { .name = __stringify(_name), \
128 : .mode = VERIFY_OCTAL_PERMISSIONS(_mode) }, \
129 : .show = _name##_show, \
130 : .store = _name##_store, \
131 : }
132 :
133 : #define __ATTR_WO(_name) { \
134 : .attr = { .name = __stringify(_name), .mode = 0200 }, \
135 : .store = _name##_store, \
136 : }
137 :
138 : #define __ATTR_RW(_name) __ATTR(_name, 0644, _name##_show, _name##_store)
139 :
140 : #define __ATTR_NULL { .attr = { .name = NULL } }
141 :
142 : #ifdef CONFIG_DEBUG_LOCK_ALLOC
143 : #define __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) { \
144 : .attr = {.name = __stringify(_name), .mode = _mode, \
145 : .ignore_lockdep = true }, \
146 : .show = _show, \
147 : .store = _store, \
148 : }
149 : #else
150 : #define __ATTR_IGNORE_LOCKDEP __ATTR
151 : #endif
152 :
153 : #define __ATTRIBUTE_GROUPS(_name) \
154 : static const struct attribute_group *_name##_groups[] = { \
155 : &_name##_group, \
156 : NULL, \
157 : }
158 :
159 : #define ATTRIBUTE_GROUPS(_name) \
160 : static const struct attribute_group _name##_group = { \
161 : .attrs = _name##_attrs, \
162 : }; \
163 : __ATTRIBUTE_GROUPS(_name)
164 :
165 : struct file;
166 : struct vm_area_struct;
167 : struct address_space;
168 :
169 : struct bin_attribute {
170 : struct attribute attr;
171 : size_t size;
172 : void *private;
173 : struct address_space *mapping;
174 : ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *,
175 : char *, loff_t, size_t);
176 : ssize_t (*write)(struct file *, struct kobject *, struct bin_attribute *,
177 : char *, loff_t, size_t);
178 : int (*mmap)(struct file *, struct kobject *, struct bin_attribute *attr,
179 : struct vm_area_struct *vma);
180 : };
181 :
182 : /**
183 : * sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
184 : * @attr: struct bin_attribute to initialize
185 : *
186 : * Initialize a dynamically allocated struct bin_attribute so we
187 : * can make lockdep happy. This is a new requirement for
188 : * attributes and initially this is only needed when lockdep is
189 : * enabled. Lockdep gives a nice error when your attribute is
190 : * added to sysfs if you don't have this.
191 : */
192 : #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
193 :
194 : /* macros to create static binary attributes easier */
195 : #define __BIN_ATTR(_name, _mode, _read, _write, _size) { \
196 : .attr = { .name = __stringify(_name), .mode = _mode }, \
197 : .read = _read, \
198 : .write = _write, \
199 : .size = _size, \
200 : }
201 :
202 : #define __BIN_ATTR_RO(_name, _size) { \
203 : .attr = { .name = __stringify(_name), .mode = 0444 }, \
204 : .read = _name##_read, \
205 : .size = _size, \
206 : }
207 :
208 : #define __BIN_ATTR_WO(_name, _size) { \
209 : .attr = { .name = __stringify(_name), .mode = 0200 }, \
210 : .write = _name##_write, \
211 : .size = _size, \
212 : }
213 :
214 : #define __BIN_ATTR_RW(_name, _size) \
215 : __BIN_ATTR(_name, 0644, _name##_read, _name##_write, _size)
216 :
217 : #define __BIN_ATTR_NULL __ATTR_NULL
218 :
219 : #define BIN_ATTR(_name, _mode, _read, _write, _size) \
220 : struct bin_attribute bin_attr_##_name = __BIN_ATTR(_name, _mode, _read, \
221 : _write, _size)
222 :
223 : #define BIN_ATTR_RO(_name, _size) \
224 : struct bin_attribute bin_attr_##_name = __BIN_ATTR_RO(_name, _size)
225 :
226 : #define BIN_ATTR_WO(_name, _size) \
227 : struct bin_attribute bin_attr_##_name = __BIN_ATTR_WO(_name, _size)
228 :
229 : #define BIN_ATTR_RW(_name, _size) \
230 : struct bin_attribute bin_attr_##_name = __BIN_ATTR_RW(_name, _size)
231 :
232 : struct sysfs_ops {
233 : ssize_t (*show)(struct kobject *, struct attribute *, char *);
234 : ssize_t (*store)(struct kobject *, struct attribute *, const char *, size_t);
235 : };
236 :
237 : #ifdef CONFIG_SYSFS
238 :
239 : int __must_check sysfs_create_dir_ns(struct kobject *kobj, const void *ns);
240 : void sysfs_remove_dir(struct kobject *kobj);
241 : int __must_check sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name,
242 : const void *new_ns);
243 : int __must_check sysfs_move_dir_ns(struct kobject *kobj,
244 : struct kobject *new_parent_kobj,
245 : const void *new_ns);
246 : int __must_check sysfs_create_mount_point(struct kobject *parent_kobj,
247 : const char *name);
248 : void sysfs_remove_mount_point(struct kobject *parent_kobj,
249 : const char *name);
250 :
251 : int __must_check sysfs_create_file_ns(struct kobject *kobj,
252 : const struct attribute *attr,
253 : const void *ns);
254 : int __must_check sysfs_create_files(struct kobject *kobj,
255 : const struct attribute * const *attr);
256 : int __must_check sysfs_chmod_file(struct kobject *kobj,
257 : const struct attribute *attr, umode_t mode);
258 : struct kernfs_node *sysfs_break_active_protection(struct kobject *kobj,
259 : const struct attribute *attr);
260 : void sysfs_unbreak_active_protection(struct kernfs_node *kn);
261 : void sysfs_remove_file_ns(struct kobject *kobj, const struct attribute *attr,
262 : const void *ns);
263 : bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr);
264 : void sysfs_remove_files(struct kobject *kobj, const struct attribute * const *attr);
265 :
266 : int __must_check sysfs_create_bin_file(struct kobject *kobj,
267 : const struct bin_attribute *attr);
268 : void sysfs_remove_bin_file(struct kobject *kobj,
269 : const struct bin_attribute *attr);
270 :
271 : int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
272 : const char *name);
273 : int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
274 : struct kobject *target,
275 : const char *name);
276 : void sysfs_remove_link(struct kobject *kobj, const char *name);
277 :
278 : int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *target,
279 : const char *old_name, const char *new_name,
280 : const void *new_ns);
281 :
282 : void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
283 : const char *name);
284 :
285 : int __must_check sysfs_create_group(struct kobject *kobj,
286 : const struct attribute_group *grp);
287 : int __must_check sysfs_create_groups(struct kobject *kobj,
288 : const struct attribute_group **groups);
289 : int __must_check sysfs_update_groups(struct kobject *kobj,
290 : const struct attribute_group **groups);
291 : int sysfs_update_group(struct kobject *kobj,
292 : const struct attribute_group *grp);
293 : void sysfs_remove_group(struct kobject *kobj,
294 : const struct attribute_group *grp);
295 : void sysfs_remove_groups(struct kobject *kobj,
296 : const struct attribute_group **groups);
297 : int sysfs_add_file_to_group(struct kobject *kobj,
298 : const struct attribute *attr, const char *group);
299 : void sysfs_remove_file_from_group(struct kobject *kobj,
300 : const struct attribute *attr, const char *group);
301 : int sysfs_merge_group(struct kobject *kobj,
302 : const struct attribute_group *grp);
303 : void sysfs_unmerge_group(struct kobject *kobj,
304 : const struct attribute_group *grp);
305 : int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name,
306 : struct kobject *target, const char *link_name);
307 : void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
308 : const char *link_name);
309 : int compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
310 : struct kobject *target_kobj,
311 : const char *target_name,
312 : const char *symlink_name);
313 :
314 : void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
315 :
316 : int __must_check sysfs_init(void);
317 :
318 3 : static inline void sysfs_enable_ns(struct kernfs_node *kn)
319 : {
320 3 : return kernfs_enable_ns(kn);
321 : }
322 :
323 : int sysfs_file_change_owner(struct kobject *kobj, const char *name, kuid_t kuid,
324 : kgid_t kgid);
325 : int sysfs_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid);
326 : int sysfs_link_change_owner(struct kobject *kobj, struct kobject *targ,
327 : const char *name, kuid_t kuid, kgid_t kgid);
328 : int sysfs_groups_change_owner(struct kobject *kobj,
329 : const struct attribute_group **groups,
330 : kuid_t kuid, kgid_t kgid);
331 : int sysfs_group_change_owner(struct kobject *kobj,
332 : const struct attribute_group *groups, kuid_t kuid,
333 : kgid_t kgid);
334 : __printf(2, 3)
335 : int sysfs_emit(char *buf, const char *fmt, ...);
336 : __printf(3, 4)
337 : int sysfs_emit_at(char *buf, int at, const char *fmt, ...);
338 :
339 : #else /* CONFIG_SYSFS */
340 :
341 : static inline int sysfs_create_dir_ns(struct kobject *kobj, const void *ns)
342 : {
343 : return 0;
344 : }
345 :
346 : static inline void sysfs_remove_dir(struct kobject *kobj)
347 : {
348 : }
349 :
350 : static inline int sysfs_rename_dir_ns(struct kobject *kobj,
351 : const char *new_name, const void *new_ns)
352 : {
353 : return 0;
354 : }
355 :
356 : static inline int sysfs_move_dir_ns(struct kobject *kobj,
357 : struct kobject *new_parent_kobj,
358 : const void *new_ns)
359 : {
360 : return 0;
361 : }
362 :
363 : static inline int sysfs_create_mount_point(struct kobject *parent_kobj,
364 : const char *name)
365 : {
366 : return 0;
367 : }
368 :
369 : static inline void sysfs_remove_mount_point(struct kobject *parent_kobj,
370 : const char *name)
371 : {
372 : }
373 :
374 : static inline int sysfs_create_file_ns(struct kobject *kobj,
375 : const struct attribute *attr,
376 : const void *ns)
377 : {
378 : return 0;
379 : }
380 :
381 : static inline int sysfs_create_files(struct kobject *kobj,
382 : const struct attribute * const *attr)
383 : {
384 : return 0;
385 : }
386 :
387 : static inline int sysfs_chmod_file(struct kobject *kobj,
388 : const struct attribute *attr, umode_t mode)
389 : {
390 : return 0;
391 : }
392 :
393 : static inline struct kernfs_node *
394 : sysfs_break_active_protection(struct kobject *kobj,
395 : const struct attribute *attr)
396 : {
397 : return NULL;
398 : }
399 :
400 : static inline void sysfs_unbreak_active_protection(struct kernfs_node *kn)
401 : {
402 : }
403 :
404 : static inline void sysfs_remove_file_ns(struct kobject *kobj,
405 : const struct attribute *attr,
406 : const void *ns)
407 : {
408 : }
409 :
410 : static inline bool sysfs_remove_file_self(struct kobject *kobj,
411 : const struct attribute *attr)
412 : {
413 : return false;
414 : }
415 :
416 : static inline void sysfs_remove_files(struct kobject *kobj,
417 : const struct attribute * const *attr)
418 : {
419 : }
420 :
421 : static inline int sysfs_create_bin_file(struct kobject *kobj,
422 : const struct bin_attribute *attr)
423 : {
424 : return 0;
425 : }
426 :
427 : static inline void sysfs_remove_bin_file(struct kobject *kobj,
428 : const struct bin_attribute *attr)
429 : {
430 : }
431 :
432 : static inline int sysfs_create_link(struct kobject *kobj,
433 : struct kobject *target, const char *name)
434 : {
435 : return 0;
436 : }
437 :
438 : static inline int sysfs_create_link_nowarn(struct kobject *kobj,
439 : struct kobject *target,
440 : const char *name)
441 : {
442 : return 0;
443 : }
444 :
445 : static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
446 : {
447 : }
448 :
449 : static inline int sysfs_rename_link_ns(struct kobject *k, struct kobject *t,
450 : const char *old_name,
451 : const char *new_name, const void *ns)
452 : {
453 : return 0;
454 : }
455 :
456 : static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
457 : const char *name)
458 : {
459 : }
460 :
461 : static inline int sysfs_create_group(struct kobject *kobj,
462 : const struct attribute_group *grp)
463 : {
464 : return 0;
465 : }
466 :
467 : static inline int sysfs_create_groups(struct kobject *kobj,
468 : const struct attribute_group **groups)
469 : {
470 : return 0;
471 : }
472 :
473 : static inline int sysfs_update_groups(struct kobject *kobj,
474 : const struct attribute_group **groups)
475 : {
476 : return 0;
477 : }
478 :
479 : static inline int sysfs_update_group(struct kobject *kobj,
480 : const struct attribute_group *grp)
481 : {
482 : return 0;
483 : }
484 :
485 : static inline void sysfs_remove_group(struct kobject *kobj,
486 : const struct attribute_group *grp)
487 : {
488 : }
489 :
490 : static inline void sysfs_remove_groups(struct kobject *kobj,
491 : const struct attribute_group **groups)
492 : {
493 : }
494 :
495 : static inline int sysfs_add_file_to_group(struct kobject *kobj,
496 : const struct attribute *attr, const char *group)
497 : {
498 : return 0;
499 : }
500 :
501 : static inline void sysfs_remove_file_from_group(struct kobject *kobj,
502 : const struct attribute *attr, const char *group)
503 : {
504 : }
505 :
506 : static inline int sysfs_merge_group(struct kobject *kobj,
507 : const struct attribute_group *grp)
508 : {
509 : return 0;
510 : }
511 :
512 : static inline void sysfs_unmerge_group(struct kobject *kobj,
513 : const struct attribute_group *grp)
514 : {
515 : }
516 :
517 : static inline int sysfs_add_link_to_group(struct kobject *kobj,
518 : const char *group_name, struct kobject *target,
519 : const char *link_name)
520 : {
521 : return 0;
522 : }
523 :
524 : static inline void sysfs_remove_link_from_group(struct kobject *kobj,
525 : const char *group_name, const char *link_name)
526 : {
527 : }
528 :
529 : static inline int compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
530 : struct kobject *target_kobj,
531 : const char *target_name,
532 : const char *symlink_name)
533 : {
534 : return 0;
535 : }
536 :
537 : static inline void sysfs_notify(struct kobject *kobj, const char *dir,
538 : const char *attr)
539 : {
540 : }
541 :
542 : static inline int __must_check sysfs_init(void)
543 : {
544 : return 0;
545 : }
546 :
547 : static inline void sysfs_enable_ns(struct kernfs_node *kn)
548 : {
549 : }
550 :
551 : static inline int sysfs_file_change_owner(struct kobject *kobj,
552 : const char *name, kuid_t kuid,
553 : kgid_t kgid)
554 : {
555 : return 0;
556 : }
557 :
558 : static inline int sysfs_link_change_owner(struct kobject *kobj,
559 : struct kobject *targ,
560 : const char *name, kuid_t kuid,
561 : kgid_t kgid)
562 : {
563 : return 0;
564 : }
565 :
566 : static inline int sysfs_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid)
567 : {
568 : return 0;
569 : }
570 :
571 : static inline int sysfs_groups_change_owner(struct kobject *kobj,
572 : const struct attribute_group **groups,
573 : kuid_t kuid, kgid_t kgid)
574 : {
575 : return 0;
576 : }
577 :
578 : static inline int sysfs_group_change_owner(struct kobject *kobj,
579 : const struct attribute_group *groups,
580 : kuid_t kuid, kgid_t kgid)
581 : {
582 : return 0;
583 : }
584 :
585 : __printf(2, 3)
586 : static inline int sysfs_emit(char *buf, const char *fmt, ...)
587 : {
588 : return 0;
589 : }
590 :
591 : __printf(3, 4)
592 : static inline int sysfs_emit_at(char *buf, int at, const char *fmt, ...)
593 : {
594 : return 0;
595 : }
596 : #endif /* CONFIG_SYSFS */
597 :
598 405 : static inline int __must_check sysfs_create_file(struct kobject *kobj,
599 : const struct attribute *attr)
600 : {
601 405 : return sysfs_create_file_ns(kobj, attr, NULL);
602 : }
603 :
604 6 : static inline void sysfs_remove_file(struct kobject *kobj,
605 : const struct attribute *attr)
606 : {
607 6 : sysfs_remove_file_ns(kobj, attr, NULL);
608 6 : }
609 :
610 : static inline int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
611 : const char *old_name, const char *new_name)
612 : {
613 : return sysfs_rename_link_ns(kobj, target, old_name, new_name, NULL);
614 : }
615 :
616 : static inline void sysfs_notify_dirent(struct kernfs_node *kn)
617 : {
618 : kernfs_notify(kn);
619 : }
620 :
621 : static inline struct kernfs_node *sysfs_get_dirent(struct kernfs_node *parent,
622 : const char *name)
623 : {
624 : return kernfs_find_and_get(parent, name);
625 : }
626 :
627 544 : static inline struct kernfs_node *sysfs_get(struct kernfs_node *kn)
628 : {
629 544 : kernfs_get(kn);
630 544 : return kn;
631 : }
632 :
633 1 : static inline void sysfs_put(struct kernfs_node *kn)
634 : {
635 1 : kernfs_put(kn);
636 : }
637 :
638 : #endif /* _SYSFS_H_ */
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