1 /* SPDX-License-Identifier: GPL-2.0 */
3 * sysfs.h - definitions for the device driver filesystem
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>
10 * Please see Documentation/filesystems/sysfs.txt for more information.
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>
33 #ifdef CONFIG_DEBUG_LOCK_ALLOC
34 bool ignore_lockdep:1;
35 struct lock_class_key *key;
36 struct lock_class_key skey;
41 * sysfs_attr_init - initialize a dynamically allocated sysfs attribute
42 * @attr: struct attribute to initialize
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.
50 #ifdef CONFIG_DEBUG_LOCK_ALLOC
51 #define sysfs_attr_init(attr) \
53 static struct lock_class_key __key; \
55 (attr)->key = &__key; \
58 #define sysfs_attr_init(attr) do {} while (0)
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.
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.
84 struct attribute_group {
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;
95 * Use these macros to make defining attributes easier. See include/linux/device.h
99 #define SYSFS_PREALLOC 010000
101 #define __ATTR(_name, _mode, _show, _store) { \
102 .attr = {.name = __stringify(_name), \
103 .mode = VERIFY_OCTAL_PERMISSIONS(_mode) }, \
108 #define __ATTR_PREALLOC(_name, _mode, _show, _store) { \
109 .attr = {.name = __stringify(_name), \
110 .mode = SYSFS_PREALLOC | VERIFY_OCTAL_PERMISSIONS(_mode) },\
115 #define __ATTR_RO(_name) { \
116 .attr = { .name = __stringify(_name), .mode = S_IRUGO }, \
117 .show = _name##_show, \
120 #define __ATTR_RO_MODE(_name, _mode) { \
121 .attr = { .name = __stringify(_name), \
122 .mode = VERIFY_OCTAL_PERMISSIONS(_mode) }, \
123 .show = _name##_show, \
126 #define __ATTR_WO(_name) { \
127 .attr = { .name = __stringify(_name), .mode = S_IWUSR }, \
128 .store = _name##_store, \
131 #define __ATTR_RW(_name) __ATTR(_name, (S_IWUSR | S_IRUGO), \
132 _name##_show, _name##_store)
134 #define __ATTR_NULL { .attr = { .name = NULL } }
136 #ifdef CONFIG_DEBUG_LOCK_ALLOC
137 #define __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) { \
138 .attr = {.name = __stringify(_name), .mode = _mode, \
139 .ignore_lockdep = true }, \
144 #define __ATTR_IGNORE_LOCKDEP __ATTR
147 #define __ATTRIBUTE_GROUPS(_name) \
148 static const struct attribute_group *_name##_groups[] = { \
153 #define ATTRIBUTE_GROUPS(_name) \
154 static const struct attribute_group _name##_group = { \
155 .attrs = _name##_attrs, \
157 __ATTRIBUTE_GROUPS(_name)
160 struct vm_area_struct;
162 struct bin_attribute {
163 struct attribute attr;
166 ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *,
167 char *, loff_t, size_t);
168 ssize_t (*write)(struct file *, struct kobject *, struct bin_attribute *,
169 char *, loff_t, size_t);
170 int (*mmap)(struct file *, struct kobject *, struct bin_attribute *attr,
171 struct vm_area_struct *vma);
175 * sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
176 * @attr: struct bin_attribute to initialize
178 * Initialize a dynamically allocated struct bin_attribute so we
179 * can make lockdep happy. This is a new requirement for
180 * attributes and initially this is only needed when lockdep is
181 * enabled. Lockdep gives a nice error when your attribute is
182 * added to sysfs if you don't have this.
184 #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
186 /* macros to create static binary attributes easier */
187 #define __BIN_ATTR(_name, _mode, _read, _write, _size) { \
188 .attr = { .name = __stringify(_name), .mode = _mode }, \
194 #define __BIN_ATTR_RO(_name, _size) { \
195 .attr = { .name = __stringify(_name), .mode = S_IRUGO }, \
196 .read = _name##_read, \
200 #define __BIN_ATTR_RW(_name, _size) __BIN_ATTR(_name, \
201 (S_IWUSR | S_IRUGO), _name##_read, \
202 _name##_write, _size)
204 #define __BIN_ATTR_NULL __ATTR_NULL
206 #define BIN_ATTR(_name, _mode, _read, _write, _size) \
207 struct bin_attribute bin_attr_##_name = __BIN_ATTR(_name, _mode, _read, \
210 #define BIN_ATTR_RO(_name, _size) \
211 struct bin_attribute bin_attr_##_name = __BIN_ATTR_RO(_name, _size)
213 #define BIN_ATTR_RW(_name, _size) \
214 struct bin_attribute bin_attr_##_name = __BIN_ATTR_RW(_name, _size)
217 ssize_t (*show)(struct kobject *, struct attribute *, char *);
218 ssize_t (*store)(struct kobject *, struct attribute *, const char *, size_t);
223 int __must_check sysfs_create_dir_ns(struct kobject *kobj, const void *ns);
224 void sysfs_remove_dir(struct kobject *kobj);
225 int __must_check sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name,
227 int __must_check sysfs_move_dir_ns(struct kobject *kobj,
228 struct kobject *new_parent_kobj,
230 int __must_check sysfs_create_mount_point(struct kobject *parent_kobj,
232 void sysfs_remove_mount_point(struct kobject *parent_kobj,
235 int __must_check sysfs_create_file_ns(struct kobject *kobj,
236 const struct attribute *attr,
238 int __must_check sysfs_create_files(struct kobject *kobj,
239 const struct attribute **attr);
240 int __must_check sysfs_chmod_file(struct kobject *kobj,
241 const struct attribute *attr, umode_t mode);
242 struct kernfs_node *sysfs_break_active_protection(struct kobject *kobj,
243 const struct attribute *attr);
244 void sysfs_unbreak_active_protection(struct kernfs_node *kn);
245 void sysfs_remove_file_ns(struct kobject *kobj, const struct attribute *attr,
247 bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr);
248 void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
250 int __must_check sysfs_create_bin_file(struct kobject *kobj,
251 const struct bin_attribute *attr);
252 void sysfs_remove_bin_file(struct kobject *kobj,
253 const struct bin_attribute *attr);
255 int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
257 int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
258 struct kobject *target,
260 void sysfs_remove_link(struct kobject *kobj, const char *name);
262 int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *target,
263 const char *old_name, const char *new_name,
266 void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
269 int __must_check sysfs_create_group(struct kobject *kobj,
270 const struct attribute_group *grp);
271 int __must_check sysfs_create_groups(struct kobject *kobj,
272 const struct attribute_group **groups);
273 int sysfs_update_group(struct kobject *kobj,
274 const struct attribute_group *grp);
275 void sysfs_remove_group(struct kobject *kobj,
276 const struct attribute_group *grp);
277 void sysfs_remove_groups(struct kobject *kobj,
278 const struct attribute_group **groups);
279 int sysfs_add_file_to_group(struct kobject *kobj,
280 const struct attribute *attr, const char *group);
281 void sysfs_remove_file_from_group(struct kobject *kobj,
282 const struct attribute *attr, const char *group);
283 int sysfs_merge_group(struct kobject *kobj,
284 const struct attribute_group *grp);
285 void sysfs_unmerge_group(struct kobject *kobj,
286 const struct attribute_group *grp);
287 int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name,
288 struct kobject *target, const char *link_name);
289 void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
290 const char *link_name);
291 int __compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
292 struct kobject *target_kobj,
293 const char *target_name);
295 void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
297 int __must_check sysfs_init(void);
299 static inline void sysfs_enable_ns(struct kernfs_node *kn)
301 return kernfs_enable_ns(kn);
305 int sysfs_emit(char *buf, const char *fmt, ...);
307 int sysfs_emit_at(char *buf, int at, const char *fmt, ...);
309 #else /* CONFIG_SYSFS */
311 static inline int sysfs_create_dir_ns(struct kobject *kobj, const void *ns)
316 static inline void sysfs_remove_dir(struct kobject *kobj)
320 static inline int sysfs_rename_dir_ns(struct kobject *kobj,
321 const char *new_name, const void *new_ns)
326 static inline int sysfs_move_dir_ns(struct kobject *kobj,
327 struct kobject *new_parent_kobj,
333 static inline int sysfs_create_mount_point(struct kobject *parent_kobj,
339 static inline void sysfs_remove_mount_point(struct kobject *parent_kobj,
344 static inline int sysfs_create_file_ns(struct kobject *kobj,
345 const struct attribute *attr,
351 static inline int sysfs_create_files(struct kobject *kobj,
352 const struct attribute **attr)
357 static inline int sysfs_chmod_file(struct kobject *kobj,
358 const struct attribute *attr, umode_t mode)
363 static inline struct kernfs_node *
364 sysfs_break_active_protection(struct kobject *kobj,
365 const struct attribute *attr)
370 static inline void sysfs_unbreak_active_protection(struct kernfs_node *kn)
374 static inline void sysfs_remove_file_ns(struct kobject *kobj,
375 const struct attribute *attr,
380 static inline bool sysfs_remove_file_self(struct kobject *kobj,
381 const struct attribute *attr)
386 static inline void sysfs_remove_files(struct kobject *kobj,
387 const struct attribute **attr)
391 static inline int sysfs_create_bin_file(struct kobject *kobj,
392 const struct bin_attribute *attr)
397 static inline void sysfs_remove_bin_file(struct kobject *kobj,
398 const struct bin_attribute *attr)
402 static inline int sysfs_create_link(struct kobject *kobj,
403 struct kobject *target, const char *name)
408 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
409 struct kobject *target,
415 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
419 static inline int sysfs_rename_link_ns(struct kobject *k, struct kobject *t,
420 const char *old_name,
421 const char *new_name, const void *ns)
426 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
431 static inline int sysfs_create_group(struct kobject *kobj,
432 const struct attribute_group *grp)
437 static inline int sysfs_create_groups(struct kobject *kobj,
438 const struct attribute_group **groups)
443 static inline int sysfs_update_group(struct kobject *kobj,
444 const struct attribute_group *grp)
449 static inline void sysfs_remove_group(struct kobject *kobj,
450 const struct attribute_group *grp)
454 static inline void sysfs_remove_groups(struct kobject *kobj,
455 const struct attribute_group **groups)
459 static inline int sysfs_add_file_to_group(struct kobject *kobj,
460 const struct attribute *attr, const char *group)
465 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
466 const struct attribute *attr, const char *group)
470 static inline int sysfs_merge_group(struct kobject *kobj,
471 const struct attribute_group *grp)
476 static inline void sysfs_unmerge_group(struct kobject *kobj,
477 const struct attribute_group *grp)
481 static inline int sysfs_add_link_to_group(struct kobject *kobj,
482 const char *group_name, struct kobject *target,
483 const char *link_name)
488 static inline void sysfs_remove_link_from_group(struct kobject *kobj,
489 const char *group_name, const char *link_name)
493 static inline int __compat_only_sysfs_link_entry_to_kobj(
494 struct kobject *kobj,
495 struct kobject *target_kobj,
496 const char *target_name)
501 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
506 static inline int __must_check sysfs_init(void)
511 static inline void sysfs_enable_ns(struct kernfs_node *kn)
516 static inline int sysfs_emit(char *buf, const char *fmt, ...)
522 static inline int sysfs_emit_at(char *buf, int at, const char *fmt, ...)
526 #endif /* CONFIG_SYSFS */
528 static inline int __must_check sysfs_create_file(struct kobject *kobj,
529 const struct attribute *attr)
531 return sysfs_create_file_ns(kobj, attr, NULL);
534 static inline void sysfs_remove_file(struct kobject *kobj,
535 const struct attribute *attr)
537 sysfs_remove_file_ns(kobj, attr, NULL);
540 static inline int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
541 const char *old_name, const char *new_name)
543 return sysfs_rename_link_ns(kobj, target, old_name, new_name, NULL);
546 static inline void sysfs_notify_dirent(struct kernfs_node *kn)
551 static inline struct kernfs_node *sysfs_get_dirent(struct kernfs_node *parent,
554 return kernfs_find_and_get(parent, name);
557 static inline struct kernfs_node *sysfs_get(struct kernfs_node *kn)
563 static inline void sysfs_put(struct kernfs_node *kn)
568 #endif /* _SYSFS_H_ */