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.
96 * See include/linux/device.h for examples..
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 = 0444 }, \
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 = 0200 }, \
128 .store = _name##_store, \
131 #define __ATTR_RW(_name) __ATTR(_name, 0644, _name##_show, _name##_store)
133 #define __ATTR_NULL { .attr = { .name = NULL } }
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 }, \
143 #define __ATTR_IGNORE_LOCKDEP __ATTR
146 #define __ATTRIBUTE_GROUPS(_name) \
147 static const struct attribute_group *_name##_groups[] = { \
152 #define ATTRIBUTE_GROUPS(_name) \
153 static const struct attribute_group _name##_group = { \
154 .attrs = _name##_attrs, \
156 __ATTRIBUTE_GROUPS(_name)
159 struct vm_area_struct;
161 struct bin_attribute {
162 struct attribute attr;
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);
174 * sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
175 * @attr: struct bin_attribute to initialize
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.
183 #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
185 /* macros to create static binary attributes easier */
186 #define __BIN_ATTR(_name, _mode, _read, _write, _size) { \
187 .attr = { .name = __stringify(_name), .mode = _mode }, \
193 #define __BIN_ATTR_RO(_name, _size) { \
194 .attr = { .name = __stringify(_name), .mode = 0444 }, \
195 .read = _name##_read, \
199 #define __BIN_ATTR_RW(_name, _size) \
200 __BIN_ATTR(_name, 0644, _name##_read, _name##_write, _size)
202 #define __BIN_ATTR_NULL __ATTR_NULL
204 #define BIN_ATTR(_name, _mode, _read, _write, _size) \
205 struct bin_attribute bin_attr_##_name = __BIN_ATTR(_name, _mode, _read, \
208 #define BIN_ATTR_RO(_name, _size) \
209 struct bin_attribute bin_attr_##_name = __BIN_ATTR_RO(_name, _size)
211 #define BIN_ATTR_RW(_name, _size) \
212 struct bin_attribute bin_attr_##_name = __BIN_ATTR_RW(_name, _size)
215 ssize_t (*show)(struct kobject *, struct attribute *, char *);
216 ssize_t (*store)(struct kobject *, struct attribute *, const char *, size_t);
221 int __must_check sysfs_create_dir_ns(struct kobject *kobj, const void *ns);
222 void sysfs_remove_dir(struct kobject *kobj);
223 int __must_check sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name,
225 int __must_check sysfs_move_dir_ns(struct kobject *kobj,
226 struct kobject *new_parent_kobj,
228 int __must_check sysfs_create_mount_point(struct kobject *parent_kobj,
230 void sysfs_remove_mount_point(struct kobject *parent_kobj,
233 int __must_check sysfs_create_file_ns(struct kobject *kobj,
234 const struct attribute *attr,
236 int __must_check sysfs_create_files(struct kobject *kobj,
237 const struct attribute **attr);
238 int __must_check sysfs_chmod_file(struct kobject *kobj,
239 const struct attribute *attr, umode_t mode);
240 struct kernfs_node *sysfs_break_active_protection(struct kobject *kobj,
241 const struct attribute *attr);
242 void sysfs_unbreak_active_protection(struct kernfs_node *kn);
243 void sysfs_remove_file_ns(struct kobject *kobj, const struct attribute *attr,
245 bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr);
246 void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
248 int __must_check sysfs_create_bin_file(struct kobject *kobj,
249 const struct bin_attribute *attr);
250 void sysfs_remove_bin_file(struct kobject *kobj,
251 const struct bin_attribute *attr);
253 int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
255 int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
256 struct kobject *target,
258 void sysfs_remove_link(struct kobject *kobj, const char *name);
260 int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *target,
261 const char *old_name, const char *new_name,
264 void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
267 int __must_check sysfs_create_group(struct kobject *kobj,
268 const struct attribute_group *grp);
269 int __must_check sysfs_create_groups(struct kobject *kobj,
270 const struct attribute_group **groups);
271 int sysfs_update_group(struct kobject *kobj,
272 const struct attribute_group *grp);
273 void sysfs_remove_group(struct kobject *kobj,
274 const struct attribute_group *grp);
275 void sysfs_remove_groups(struct kobject *kobj,
276 const struct attribute_group **groups);
277 int sysfs_add_file_to_group(struct kobject *kobj,
278 const struct attribute *attr, const char *group);
279 void sysfs_remove_file_from_group(struct kobject *kobj,
280 const struct attribute *attr, const char *group);
281 int sysfs_merge_group(struct kobject *kobj,
282 const struct attribute_group *grp);
283 void sysfs_unmerge_group(struct kobject *kobj,
284 const struct attribute_group *grp);
285 int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name,
286 struct kobject *target, const char *link_name);
287 void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
288 const char *link_name);
289 int __compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
290 struct kobject *target_kobj,
291 const char *target_name);
293 void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
295 int __must_check sysfs_init(void);
297 static inline void sysfs_enable_ns(struct kernfs_node *kn)
299 return kernfs_enable_ns(kn);
302 #else /* CONFIG_SYSFS */
304 static inline int sysfs_create_dir_ns(struct kobject *kobj, const void *ns)
309 static inline void sysfs_remove_dir(struct kobject *kobj)
313 static inline int sysfs_rename_dir_ns(struct kobject *kobj,
314 const char *new_name, const void *new_ns)
319 static inline int sysfs_move_dir_ns(struct kobject *kobj,
320 struct kobject *new_parent_kobj,
326 static inline int sysfs_create_mount_point(struct kobject *parent_kobj,
332 static inline void sysfs_remove_mount_point(struct kobject *parent_kobj,
337 static inline int sysfs_create_file_ns(struct kobject *kobj,
338 const struct attribute *attr,
344 static inline int sysfs_create_files(struct kobject *kobj,
345 const struct attribute **attr)
350 static inline int sysfs_chmod_file(struct kobject *kobj,
351 const struct attribute *attr, umode_t mode)
356 static inline struct kernfs_node *
357 sysfs_break_active_protection(struct kobject *kobj,
358 const struct attribute *attr)
363 static inline void sysfs_unbreak_active_protection(struct kernfs_node *kn)
367 static inline void sysfs_remove_file_ns(struct kobject *kobj,
368 const struct attribute *attr,
373 static inline bool sysfs_remove_file_self(struct kobject *kobj,
374 const struct attribute *attr)
379 static inline void sysfs_remove_files(struct kobject *kobj,
380 const struct attribute **attr)
384 static inline int sysfs_create_bin_file(struct kobject *kobj,
385 const struct bin_attribute *attr)
390 static inline void sysfs_remove_bin_file(struct kobject *kobj,
391 const struct bin_attribute *attr)
395 static inline int sysfs_create_link(struct kobject *kobj,
396 struct kobject *target, const char *name)
401 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
402 struct kobject *target,
408 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
412 static inline int sysfs_rename_link_ns(struct kobject *k, struct kobject *t,
413 const char *old_name,
414 const char *new_name, const void *ns)
419 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
424 static inline int sysfs_create_group(struct kobject *kobj,
425 const struct attribute_group *grp)
430 static inline int sysfs_create_groups(struct kobject *kobj,
431 const struct attribute_group **groups)
436 static inline int sysfs_update_group(struct kobject *kobj,
437 const struct attribute_group *grp)
442 static inline void sysfs_remove_group(struct kobject *kobj,
443 const struct attribute_group *grp)
447 static inline void sysfs_remove_groups(struct kobject *kobj,
448 const struct attribute_group **groups)
452 static inline int sysfs_add_file_to_group(struct kobject *kobj,
453 const struct attribute *attr, const char *group)
458 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
459 const struct attribute *attr, const char *group)
463 static inline int sysfs_merge_group(struct kobject *kobj,
464 const struct attribute_group *grp)
469 static inline void sysfs_unmerge_group(struct kobject *kobj,
470 const struct attribute_group *grp)
474 static inline int sysfs_add_link_to_group(struct kobject *kobj,
475 const char *group_name, struct kobject *target,
476 const char *link_name)
481 static inline void sysfs_remove_link_from_group(struct kobject *kobj,
482 const char *group_name, const char *link_name)
486 static inline int __compat_only_sysfs_link_entry_to_kobj(
487 struct kobject *kobj,
488 struct kobject *target_kobj,
489 const char *target_name)
494 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
499 static inline int __must_check sysfs_init(void)
504 static inline void sysfs_enable_ns(struct kernfs_node *kn)
508 #endif /* CONFIG_SYSFS */
510 static inline int __must_check sysfs_create_file(struct kobject *kobj,
511 const struct attribute *attr)
513 return sysfs_create_file_ns(kobj, attr, NULL);
516 static inline void sysfs_remove_file(struct kobject *kobj,
517 const struct attribute *attr)
519 sysfs_remove_file_ns(kobj, attr, NULL);
522 static inline int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
523 const char *old_name, const char *new_name)
525 return sysfs_rename_link_ns(kobj, target, old_name, new_name, NULL);
528 static inline void sysfs_notify_dirent(struct kernfs_node *kn)
533 static inline struct kernfs_node *sysfs_get_dirent(struct kernfs_node *parent,
536 return kernfs_find_and_get(parent, name);
539 static inline struct kernfs_node *sysfs_get(struct kernfs_node *kn)
545 static inline void sysfs_put(struct kernfs_node *kn)
550 #endif /* _SYSFS_H_ */