aboutsummaryrefslogtreecommitdiff
path: root/include/linux/sysfs.h
blob: 86067dbe774517540d6e3b32e4ce63e456f9bcd9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
/* SPDX-License-Identifier: GPL-2.0 */
/*
 * sysfs.h - definitions for the device driver filesystem
 *
 * Copyright (c) 2001,2002 Patrick Mochel
 * Copyright (c) 2004 Silicon Graphics, Inc.
 * Copyright (c) 2007 SUSE Linux Products GmbH
 * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
 *
 * Please see Documentation/filesystems/sysfs.rst for more information.
 */

#ifndef _SYSFS_H_
#define _SYSFS_H_

#include <linux/kernfs.h>
#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/kobject_ns.h>
#include <linux/stat.h>
#include <linux/atomic.h>

struct kobject;
struct module;
struct bin_attribute;
enum kobj_ns_type;

struct attribute {
	const char		*name;
	umode_t			mode;
#ifdef CONFIG_DEBUG_LOCK_ALLOC
	bool			ignore_lockdep:1;
	struct lock_class_key	*key;
	struct lock_class_key	skey;
#endif
};

/**
 *	sysfs_attr_init - initialize a dynamically allocated sysfs attribute
 *	@attr: struct attribute to initialize
 *
 *	Initialize a dynamically allocated struct attribute so we can
 *	make lockdep happy.  This is a new requirement for attributes
 *	and initially this is only needed when lockdep is enabled.
 *	Lockdep gives a nice error when your attribute is added to
 *	sysfs if you don't have this.
 */
#ifdef CONFIG_DEBUG_LOCK_ALLOC
#define sysfs_attr_init(attr)				\
do {							\
	static struct lock_class_key __key;		\
							\
	(attr)->key = &__key;				\
} while (0)
#else
#define sysfs_attr_init(attr) do {} while (0)
#endif

/**
 * struct attribute_group - data structure used to declare an attribute group.
 * @name:	Optional: Attribute group name
 *		If specified, the attribute group will be created in
 *		a new subdirectory with this name.
 * @is_visible:	Optional: Function to return permissions associated with an
 *		attribute of the group. Will be called repeatedly for each
 *		non-binary attribute in the group. Only read/write
 *		permissions as well as SYSFS_PREALLOC are accepted. Must
 *		return 0 if an attribute is not visible. The returned value
 *		will replace static permissions defined in struct attribute.
 * @is_bin_visible:
 *		Optional: Function to return permissions associated with a
 *		binary attribute of the group. Will be called repeatedly
 *		for each binary attribute in the group. Only read/write
 *		permissions as well as SYSFS_PREALLOC are accepted. Must
 *		return 0 if a binary attribute is not visible. The returned
 *		value will replace static permissions defined in
 *		struct bin_attribute.
 * @attrs:	Pointer to NULL terminated list of attributes.
 * @bin_attrs:	Pointer to NULL terminated list of binary attributes.
 *		Either attrs or bin_attrs or both must be provided.
 */
struct attribute_group {
	const char		*name;
	umode_t			(*is_visible)(struct kobject *,
					      struct attribute *, int);
	umode_t			(*is_bin_visible)(struct kobject *,
						  struct bin_attribute *, int);
	struct attribute	**attrs;
	struct bin_attribute	**bin_attrs;
};

/*
 * Use these macros to make defining attributes easier.
 * See include/linux/device.h for examples..
 */

#define SYSFS_PREALLOC 010000

#define __ATTR(_name, _mode, _show, _store) {				\
	.attr = {.name = __stringify(_name),				\
		 .mode = VERIFY_OCTAL_PERMISSIONS(_mode) },		\
	.show	= _show,						\
	.store	= _store,						\
}

#define __ATTR_PREALLOC(_name, _mode, _show, _store) {			\
	.attr = {.name = __stringify(_name),				\
		 .mode = SYSFS_PREALLOC | VERIFY_OCTAL_PERMISSIONS(_mode) },\
	.show	= _show,						\
	.store	= _store,						\
}

#define __ATTR_RO(_name) {						\
	.attr	= { .name = __stringify(_name), .mode = 0444 },		\
	.show	= _name##_show,						\
}

#define __ATTR_RO_MODE(_name, _mode) {					\
	.attr	= { .name = __stringify(_name),				\
		    .mode = VERIFY_OCTAL_PERMISSIONS(_mode) },		\
	.show	= _name##_show,						\
}

#define __ATTR_WO(_name) {						\
	.attr	= { .name = __stringify(_name), .mode = 0200 },		\
	.store	= _name##_store,					\
}

#define __ATTR_RW(_name) __ATTR(_name, 0644, _name##_show, _name##_store)

#define __ATTR_NULL { .attr = { .name = NULL } }

#ifdef CONFIG_DEBUG_LOCK_ALLOC
#define __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) {	\
	.attr = {.name = __stringify(_name), .mode = _mode,	\
			.ignore_lockdep = true },		\
	.show		= _show,				\
	.store		= _store,				\
}
#else
#define __ATTR_IGNORE_LOCKDEP	__ATTR
#endif

#define __ATTRIBUTE_GROUPS(_name)				\
static const struct attribute_group *_name##_groups[] = {	\
	&_name##_group,						\
	NULL,							\
}

#define ATTRIBUTE_GROUPS(_name)					\
static const struct attribute_group _name##_group = {		\
	.attrs = _name##_attrs,					\
};								\
__ATTRIBUTE_GROUPS(_name)

struct file;
struct vm_area_struct;

struct bin_attribute {
	struct attribute	attr;
	size_t			size;
	void			*private;
	ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *,
			char *, loff_t, size_t);
	ssize_t (*write)(struct file *, struct kobject *, struct bin_attribute *,
			 char *, loff_t, size_t);
	int (*mmap)(struct file *, struct kobject *, struct bin_attribute *attr,
		    struct vm_area_struct *vma);
};

/**
 *	sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
 *	@attr: struct bin_attribute to initialize
 *
 *	Initialize a dynamically allocated struct bin_attribute so we
 *	can make lockdep happy.  This is a new requirement for
 *	attributes and initially this is only needed when lockdep is
 *	enabled.  Lockdep gives a nice error when your attribute is
 *	added to sysfs if you don't have this.
 */
#define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)

/* macros to create static binary attributes easier */
#define __BIN_ATTR(_name, _mode, _read, _write, _size) {		\
	.attr = { .name = __stringify(_name), .mode = _mode },		\
	.read	= _read,						\
	.write	= _write,						\
	.size	= _size,						\
}

#define __BIN_ATTR_RO(_name, _size) {					\
	.attr	= { .name = __stringify(_name), .mode = 0444 },		\
	.read	= _name##_read,						\
	.size	= _size,						\
}

#define __BIN_ATTR_WO(_name, _size) {					\
	.attr	= { .name = __stringify(_name), .mode = 0200 },		\
	.write	= _name##_write,					\
	.size	= _size,						\
}

#define __BIN_ATTR_RW(_name, _size)					\
	__BIN_ATTR(_name, 0644, _name##_read, _name##_write, _size)

#define __BIN_ATTR_NULL __ATTR_NULL

#define BIN_ATTR(_name, _mode, _read, _write, _size)			\
struct bin_attribute bin_attr_##_name = __BIN_ATTR(_name, _mode, _read,	\
					_write, _size)

#define BIN_ATTR_RO(_name, _size)					\
struct bin_attribute bin_attr_##_name = __BIN_ATTR_RO(_name, _size)

#define BIN_ATTR_WO(_name, _size)					\
struct bin_attribute bin_attr_##_name = __BIN_ATTR_WO(_name, _size)

#define BIN_ATTR_RW(_name, _size)					\
struct bin_attribute bin_attr_##_name = __BIN_ATTR_RW(_name, _size)

struct sysfs_ops {
	ssize_t	(*show)(struct kobject *, struct attribute *, char *);
	ssize_t	(*store)(struct kobject *, struct attribute *, const char *, size_t);
};

#ifdef CONFIG_SYSFS

int __must_check sysfs_create_dir_ns(struct kobject *kobj, const void *ns);
void sysfs_remove_dir(struct kobject *kobj);
int __must_check sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name,
				     const void *new_ns);
int __must_check sysfs_move_dir_ns(struct kobject *kobj,
				   struct kobject *new_parent_kobj,
				   const void *new_ns);
int __must_check sysfs_create_mount_point(struct kobject *parent_kobj,
					  const char *name);
void sysfs_remove_mount_point(struct kobject *parent_kobj,
			      const char *name);

int __must_check sysfs_create_file_ns(struct kobject *kobj,
				      const struct attribute *attr,
				      const void *ns);
int __must_check sysfs_create_files(struct kobject *kobj,
				   const struct attribute * const *attr);
int __must_check sysfs_chmod_file(struct kobject *kobj,
				  const struct attribute *attr, umode_t mode);
struct kernfs_node *sysfs_break_active_protection(struct kobject *kobj,
						  const struct attribute *attr);
void sysfs_unbreak_active_protection(struct kernfs_node *kn);
void sysfs_remove_file_ns(struct kobject *kobj, const struct attribute *attr,
			  const void *ns);
bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr);
void sysfs_remove_files(struct kobject *kobj, const struct attribute * const *attr);

int __must_check sysfs_create_bin_file(struct kobject *kobj,
				       const struct bin_attribute *attr);
void sysfs_remove_bin_file(struct kobject *kobj,
			   const struct bin_attribute *attr);

int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
				   const char *name);
int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
					  struct kobject *target,
					  const char *name);
void sysfs_remove_link(struct kobject *kobj, const char *name);

int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *target,
			 const char *old_name, const char *new_name,
			 const void *new_ns);

void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
			const char *name);

int __must_check sysfs_create_group(struct kobject *kobj,
				    const struct attribute_group *grp);
int __must_check sysfs_create_groups(struct kobject *kobj,
				     const struct attribute_group **groups);
int __must_check sysfs_update_groups(struct kobject *kobj,
				     const struct attribute_group **groups);
int sysfs_update_group(struct kobject *kobj,
		       const struct attribute_group *grp);
void sysfs_remove_group(struct kobject *kobj,
			const struct attribute_group *grp);
void sysfs_remove_groups(struct kobject *kobj,
			 const struct attribute_group **groups);
int sysfs_add_file_to_group(struct kobject *kobj,
			const struct attribute *attr, const char *group);
void sysfs_remove_file_from_group(struct kobject *kobj,
			const struct attribute *attr, const char *group);
int sysfs_merge_group(struct kobject *kobj,
		       const struct attribute_group *grp);
void sysfs_unmerge_group(struct kobject *kobj,
		       const struct attribute_group *grp);
int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name,
			    struct kobject *target, const char *link_name);
void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
				  const char *link_name);
int compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
					 struct kobject *target_kobj,
					 const char *target_name,
					 const char *symlink_name);

void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);

int __must_check sysfs_init(void);

static inline void sysfs_enable_ns(struct kernfs_node *kn)
{
	return kernfs_enable_ns(kn);
}

int sysfs_file_change_owner(struct kobject *kobj, const char *name, kuid_t kuid,
			    kgid_t kgid);
int sysfs_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid);
int sysfs_link_change_owner(struct kobject *kobj, struct kobject *targ,
			    const char *name, kuid_t kuid, kgid_t kgid);
int sysfs_groups_change_owner(struct kobject *kobj,
			      const struct attribute_group **groups,
			      kuid_t kuid, kgid_t kgid);
int sysfs_group_change_owner(struct kobject *kobj,
			     const struct attribute_group *groups, kuid_t kuid,
			     kgid_t kgid);

#else /* CONFIG_SYSFS */

static inline int sysfs_create_dir_ns(struct kobject *kobj, const void *ns)
{
	return 0;
}

static inline void sysfs_remove_dir(struct kobject *kobj)
{
}

static inline int sysfs_rename_dir_ns(struct kobject *kobj,
				      const char *new_name, const void *new_ns)
{
	return 0;
}

static inline int sysfs_move_dir_ns(struct kobject *kobj,
				    struct kobject *new_parent_kobj,
				    const void *new_ns)
{
	return 0;
}

static inline int sysfs_create_mount_point(struct kobject *parent_kobj,
					   const char *name)
{
	return 0;
}

static inline void sysfs_remove_mount_point(struct kobject *parent_kobj,
					    const char *name)
{
}

static inline int sysfs_create_file_ns(struct kobject *kobj,
				       const struct attribute *attr,
				       const void *ns)
{
	return 0;
}

static inline int sysfs_create_files(struct kobject *kobj,
				    const struct attribute * const *attr)
{
	return 0;
}

static inline int sysfs_chmod_file(struct kobject *kobj,
				   const struct attribute *attr, umode_t mode)
{
	return 0;
}

static inline struct kernfs_node *
sysfs_break_active_protection(struct kobject *kobj,
			      const struct attribute *attr)
{
	return NULL;
}

static inline void sysfs_unbreak_active_protection(struct kernfs_node *kn)
{
}

static inline void sysfs_remove_file_ns(struct kobject *kobj,
					const struct attribute *attr,
					const void *ns)
{
}

static inline bool sysfs_remove_file_self(struct kobject *kobj,
					  const struct attribute *attr)
{
	return false;
}

static inline void sysfs_remove_files(struct kobject *kobj,
				     const struct attribute * const *attr)
{
}

static inline int sysfs_create_bin_file(struct kobject *kobj,
					const struct bin_attribute *attr)
{
	return 0;
}

static inline void sysfs_remove_bin_file(struct kobject *kobj,
					 const struct bin_attribute *attr)
{
}

static inline int sysfs_create_link(struct kobject *kobj,
				    struct kobject *target, const char *name)
{
	return 0;
}

static inline int sysfs_create_link_nowarn(struct kobject *kobj,
					   struct kobject *target,
					   const char *name)
{
	return 0;
}

static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
{
}

static inline int sysfs_rename_link_ns(struct kobject *k, struct kobject *t,
				       const char *old_name,
				       const char *new_name, const void *ns)
{
	return 0;
}

static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
				     const char *name)
{
}

static inline int sysfs_create_group(struct kobject *kobj,
				     const struct attribute_group *grp)
{
	return 0;
}

static inline int sysfs_create_groups(struct kobject *kobj,
				      const struct attribute_group **groups)
{
	return 0;
}

static inline int sysfs_update_groups(struct kobject *kobj,
				      const struct attribute_group **groups)
{
	return 0;
}

static inline int sysfs_update_group(struct kobject *kobj,
				const struct attribute_group *grp)
{
	return 0;
}

static inline void sysfs_remove_group(struct kobject *kobj,
				      const struct attribute_group *grp)
{
}

static inline void sysfs_remove_groups(struct kobject *kobj,
				       const struct attribute_group **groups)
{
}

static inline int sysfs_add_file_to_group(struct kobject *kobj,
		const struct attribute *attr, const char *group)
{
	return 0;
}

static inline void sysfs_remove_file_from_group(struct kobject *kobj,
		const struct attribute *attr, const char *group)
{
}

static inline int sysfs_merge_group(struct kobject *kobj,
		       const struct attribute_group *grp)
{
	return 0;
}

static inline void sysfs_unmerge_group(struct kobject *kobj,
		       const struct attribute_group *grp)
{
}

static inline int sysfs_add_link_to_group(struct kobject *kobj,
		const char *group_name, struct kobject *target,
		const char *link_name)
{
	return 0;
}

static inline void sysfs_remove_link_from_group(struct kobject *kobj,
		const char *group_name, const char *link_name)
{
}

static inline int compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
						       struct kobject *target_kobj,
						       const char *target_name,
						       const char *symlink_name)
{
	return 0;
}

static inline void sysfs_notify(struct kobject *kobj, const char *dir,
				const char *attr)
{
}

static inline int __must_check sysfs_init(void)
{
	return 0;
}

static inline void sysfs_enable_ns(struct kernfs_node *kn)
{
}

static inline int sysfs_file_change_owner(struct kobject *kobj,
					  const char *name, kuid_t kuid,
					  kgid_t kgid)
{
	return 0;
}

static inline int sysfs_link_change_owner(struct kobject *kobj,
					  struct kobject *targ,
					  const char *name, kuid_t kuid,
					  kgid_t kgid)
{
	return 0;
}

static inline int sysfs_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid)
{
	return 0;
}

static inline int sysfs_groups_change_owner(struct kobject *kobj,
			  const struct attribute_group **groups,
			  kuid_t kuid, kgid_t kgid)
{
	return 0;
}

static inline int sysfs_group_change_owner(struct kobject *kobj,
					   const struct attribute_group *groups,
					   kuid_t kuid, kgid_t kgid)
{
	return 0;
}

#endif /* CONFIG_SYSFS */

static inline int __must_check sysfs_create_file(struct kobject *kobj,
						 const struct attribute *attr)
{
	return sysfs_create_file_ns(kobj, attr, NULL);
}

static inline void sysfs_remove_file(struct kobject *kobj,
				     const struct attribute *attr)
{
	sysfs_remove_file_ns(kobj, attr, NULL);
}

static inline int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
				    const char *old_name, const char *new_name)
{
	return sysfs_rename_link_ns(kobj, target, old_name, new_name, NULL);
}

static inline void sysfs_notify_dirent(struct kernfs_node *kn)
{
	kernfs_notify(kn);
}

static inline struct kernfs_node *sysfs_get_dirent(struct kernfs_node *parent,
						   const char *name)
{
	return kernfs_find_and_get(parent, name);
}

static inline struct kernfs_node *sysfs_get(struct kernfs_node *kn)
{
	kernfs_get(kn);
	return kn;
}

static inline void sysfs_put(struct kernfs_node *kn)
{
	kernfs_put(kn);
}

#endif /* _SYSFS_H_ */