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.rst 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_RW_MODE(_name, _mode) { \
127 .attr = { .name = __stringify(_name), \
128 .mode = VERIFY_OCTAL_PERMISSIONS(_mode) }, \
129 .show = _name##_show, \
130 .store = _name##_store, \
133 #define __ATTR_WO(_name) { \
134 .attr = { .name = __stringify(_name), .mode = 0200 }, \
135 .store = _name##_store, \
138 #define __ATTR_RW(_name) __ATTR(_name, 0644, _name##_show, _name##_store)
140 #define __ATTR_NULL { .attr = { .name = NULL } }
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 }, \
150 #define __ATTR_IGNORE_LOCKDEP __ATTR
153 #define __ATTRIBUTE_GROUPS(_name) \
154 static const struct attribute_group *_name##_groups[] = { \
159 #define ATTRIBUTE_GROUPS(_name) \
160 static const struct attribute_group _name##_group = { \
161 .attrs = _name##_attrs, \
163 __ATTRIBUTE_GROUPS(_name)
165 #define BIN_ATTRIBUTE_GROUPS(_name) \
166 static const struct attribute_group _name##_group = { \
167 .bin_attrs = _name##_attrs, \
169 __ATTRIBUTE_GROUPS(_name)
172 struct vm_area_struct;
173 struct address_space;
175 struct bin_attribute {
176 struct attribute attr;
179 struct address_space *(*f_mapping)(void);
180 ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *,
181 char *, loff_t, size_t);
182 ssize_t (*write)(struct file *, struct kobject *, struct bin_attribute *,
183 char *, loff_t, size_t);
184 int (*mmap)(struct file *, struct kobject *, struct bin_attribute *attr,
185 struct vm_area_struct *vma);
189 * sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
190 * @attr: struct bin_attribute to initialize
192 * Initialize a dynamically allocated struct bin_attribute so we
193 * can make lockdep happy. This is a new requirement for
194 * attributes and initially this is only needed when lockdep is
195 * enabled. Lockdep gives a nice error when your attribute is
196 * added to sysfs if you don't have this.
198 #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
200 /* macros to create static binary attributes easier */
201 #define __BIN_ATTR(_name, _mode, _read, _write, _size) { \
202 .attr = { .name = __stringify(_name), .mode = _mode }, \
208 #define __BIN_ATTR_RO(_name, _size) { \
209 .attr = { .name = __stringify(_name), .mode = 0444 }, \
210 .read = _name##_read, \
214 #define __BIN_ATTR_WO(_name, _size) { \
215 .attr = { .name = __stringify(_name), .mode = 0200 }, \
216 .write = _name##_write, \
220 #define __BIN_ATTR_RW(_name, _size) \
221 __BIN_ATTR(_name, 0644, _name##_read, _name##_write, _size)
223 #define __BIN_ATTR_NULL __ATTR_NULL
225 #define BIN_ATTR(_name, _mode, _read, _write, _size) \
226 struct bin_attribute bin_attr_##_name = __BIN_ATTR(_name, _mode, _read, \
229 #define BIN_ATTR_RO(_name, _size) \
230 struct bin_attribute bin_attr_##_name = __BIN_ATTR_RO(_name, _size)
232 #define BIN_ATTR_WO(_name, _size) \
233 struct bin_attribute bin_attr_##_name = __BIN_ATTR_WO(_name, _size)
235 #define BIN_ATTR_RW(_name, _size) \
236 struct bin_attribute bin_attr_##_name = __BIN_ATTR_RW(_name, _size)
239 #define __BIN_ATTR_ADMIN_RO(_name, _size) { \
240 .attr = { .name = __stringify(_name), .mode = 0400 }, \
241 .read = _name##_read, \
245 #define __BIN_ATTR_ADMIN_RW(_name, _size) \
246 __BIN_ATTR(_name, 0600, _name##_read, _name##_write, _size)
248 #define BIN_ATTR_ADMIN_RO(_name, _size) \
249 struct bin_attribute bin_attr_##_name = __BIN_ATTR_ADMIN_RO(_name, _size)
251 #define BIN_ATTR_ADMIN_RW(_name, _size) \
252 struct bin_attribute bin_attr_##_name = __BIN_ATTR_ADMIN_RW(_name, _size)
255 ssize_t (*show)(struct kobject *, struct attribute *, char *);
256 ssize_t (*store)(struct kobject *, struct attribute *, const char *, size_t);
261 int __must_check sysfs_create_dir_ns(struct kobject *kobj, const void *ns);
262 void sysfs_remove_dir(struct kobject *kobj);
263 int __must_check sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name,
265 int __must_check sysfs_move_dir_ns(struct kobject *kobj,
266 struct kobject *new_parent_kobj,
268 int __must_check sysfs_create_mount_point(struct kobject *parent_kobj,
270 void sysfs_remove_mount_point(struct kobject *parent_kobj,
273 int __must_check sysfs_create_file_ns(struct kobject *kobj,
274 const struct attribute *attr,
276 int __must_check sysfs_create_files(struct kobject *kobj,
277 const struct attribute * const *attr);
278 int __must_check sysfs_chmod_file(struct kobject *kobj,
279 const struct attribute *attr, umode_t mode);
280 struct kernfs_node *sysfs_break_active_protection(struct kobject *kobj,
281 const struct attribute *attr);
282 void sysfs_unbreak_active_protection(struct kernfs_node *kn);
283 void sysfs_remove_file_ns(struct kobject *kobj, const struct attribute *attr,
285 bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr);
286 void sysfs_remove_files(struct kobject *kobj, const struct attribute * const *attr);
288 int __must_check sysfs_create_bin_file(struct kobject *kobj,
289 const struct bin_attribute *attr);
290 void sysfs_remove_bin_file(struct kobject *kobj,
291 const struct bin_attribute *attr);
293 int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
295 int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
296 struct kobject *target,
298 void sysfs_remove_link(struct kobject *kobj, const char *name);
300 int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *target,
301 const char *old_name, const char *new_name,
304 void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
307 int __must_check sysfs_create_group(struct kobject *kobj,
308 const struct attribute_group *grp);
309 int __must_check sysfs_create_groups(struct kobject *kobj,
310 const struct attribute_group **groups);
311 int __must_check sysfs_update_groups(struct kobject *kobj,
312 const struct attribute_group **groups);
313 int sysfs_update_group(struct kobject *kobj,
314 const struct attribute_group *grp);
315 void sysfs_remove_group(struct kobject *kobj,
316 const struct attribute_group *grp);
317 void sysfs_remove_groups(struct kobject *kobj,
318 const struct attribute_group **groups);
319 int sysfs_add_file_to_group(struct kobject *kobj,
320 const struct attribute *attr, const char *group);
321 void sysfs_remove_file_from_group(struct kobject *kobj,
322 const struct attribute *attr, const char *group);
323 int sysfs_merge_group(struct kobject *kobj,
324 const struct attribute_group *grp);
325 void sysfs_unmerge_group(struct kobject *kobj,
326 const struct attribute_group *grp);
327 int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name,
328 struct kobject *target, const char *link_name);
329 void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
330 const char *link_name);
331 int compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
332 struct kobject *target_kobj,
333 const char *target_name,
334 const char *symlink_name);
336 void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
338 int __must_check sysfs_init(void);
340 static inline void sysfs_enable_ns(struct kernfs_node *kn)
342 return kernfs_enable_ns(kn);
345 int sysfs_file_change_owner(struct kobject *kobj, const char *name, kuid_t kuid,
347 int sysfs_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid);
348 int sysfs_link_change_owner(struct kobject *kobj, struct kobject *targ,
349 const char *name, kuid_t kuid, kgid_t kgid);
350 int sysfs_groups_change_owner(struct kobject *kobj,
351 const struct attribute_group **groups,
352 kuid_t kuid, kgid_t kgid);
353 int sysfs_group_change_owner(struct kobject *kobj,
354 const struct attribute_group *groups, kuid_t kuid,
357 int sysfs_emit(char *buf, const char *fmt, ...);
359 int sysfs_emit_at(char *buf, int at, const char *fmt, ...);
361 #else /* CONFIG_SYSFS */
363 static inline int sysfs_create_dir_ns(struct kobject *kobj, const void *ns)
368 static inline void sysfs_remove_dir(struct kobject *kobj)
372 static inline int sysfs_rename_dir_ns(struct kobject *kobj,
373 const char *new_name, const void *new_ns)
378 static inline int sysfs_move_dir_ns(struct kobject *kobj,
379 struct kobject *new_parent_kobj,
385 static inline int sysfs_create_mount_point(struct kobject *parent_kobj,
391 static inline void sysfs_remove_mount_point(struct kobject *parent_kobj,
396 static inline int sysfs_create_file_ns(struct kobject *kobj,
397 const struct attribute *attr,
403 static inline int sysfs_create_files(struct kobject *kobj,
404 const struct attribute * const *attr)
409 static inline int sysfs_chmod_file(struct kobject *kobj,
410 const struct attribute *attr, umode_t mode)
415 static inline struct kernfs_node *
416 sysfs_break_active_protection(struct kobject *kobj,
417 const struct attribute *attr)
422 static inline void sysfs_unbreak_active_protection(struct kernfs_node *kn)
426 static inline void sysfs_remove_file_ns(struct kobject *kobj,
427 const struct attribute *attr,
432 static inline bool sysfs_remove_file_self(struct kobject *kobj,
433 const struct attribute *attr)
438 static inline void sysfs_remove_files(struct kobject *kobj,
439 const struct attribute * const *attr)
443 static inline int sysfs_create_bin_file(struct kobject *kobj,
444 const struct bin_attribute *attr)
449 static inline void sysfs_remove_bin_file(struct kobject *kobj,
450 const struct bin_attribute *attr)
454 static inline int sysfs_create_link(struct kobject *kobj,
455 struct kobject *target, const char *name)
460 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
461 struct kobject *target,
467 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
471 static inline int sysfs_rename_link_ns(struct kobject *k, struct kobject *t,
472 const char *old_name,
473 const char *new_name, const void *ns)
478 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
483 static inline int sysfs_create_group(struct kobject *kobj,
484 const struct attribute_group *grp)
489 static inline int sysfs_create_groups(struct kobject *kobj,
490 const struct attribute_group **groups)
495 static inline int sysfs_update_groups(struct kobject *kobj,
496 const struct attribute_group **groups)
501 static inline int sysfs_update_group(struct kobject *kobj,
502 const struct attribute_group *grp)
507 static inline void sysfs_remove_group(struct kobject *kobj,
508 const struct attribute_group *grp)
512 static inline void sysfs_remove_groups(struct kobject *kobj,
513 const struct attribute_group **groups)
517 static inline int sysfs_add_file_to_group(struct kobject *kobj,
518 const struct attribute *attr, const char *group)
523 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
524 const struct attribute *attr, const char *group)
528 static inline int sysfs_merge_group(struct kobject *kobj,
529 const struct attribute_group *grp)
534 static inline void sysfs_unmerge_group(struct kobject *kobj,
535 const struct attribute_group *grp)
539 static inline int sysfs_add_link_to_group(struct kobject *kobj,
540 const char *group_name, struct kobject *target,
541 const char *link_name)
546 static inline void sysfs_remove_link_from_group(struct kobject *kobj,
547 const char *group_name, const char *link_name)
551 static inline int compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
552 struct kobject *target_kobj,
553 const char *target_name,
554 const char *symlink_name)
559 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
564 static inline int __must_check sysfs_init(void)
569 static inline void sysfs_enable_ns(struct kernfs_node *kn)
573 static inline int sysfs_file_change_owner(struct kobject *kobj,
574 const char *name, kuid_t kuid,
580 static inline int sysfs_link_change_owner(struct kobject *kobj,
581 struct kobject *targ,
582 const char *name, kuid_t kuid,
588 static inline int sysfs_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid)
593 static inline int sysfs_groups_change_owner(struct kobject *kobj,
594 const struct attribute_group **groups,
595 kuid_t kuid, kgid_t kgid)
600 static inline int sysfs_group_change_owner(struct kobject *kobj,
601 const struct attribute_group *groups,
602 kuid_t kuid, kgid_t kgid)
608 static inline int sysfs_emit(char *buf, const char *fmt, ...)
614 static inline int sysfs_emit_at(char *buf, int at, const char *fmt, ...)
618 #endif /* CONFIG_SYSFS */
620 static inline int __must_check sysfs_create_file(struct kobject *kobj,
621 const struct attribute *attr)
623 return sysfs_create_file_ns(kobj, attr, NULL);
626 static inline void sysfs_remove_file(struct kobject *kobj,
627 const struct attribute *attr)
629 sysfs_remove_file_ns(kobj, attr, NULL);
632 static inline int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
633 const char *old_name, const char *new_name)
635 return sysfs_rename_link_ns(kobj, target, old_name, new_name, NULL);
638 static inline void sysfs_notify_dirent(struct kernfs_node *kn)
643 static inline struct kernfs_node *sysfs_get_dirent(struct kernfs_node *parent,
646 return kernfs_find_and_get(parent, name);
649 static inline struct kernfs_node *sysfs_get(struct kernfs_node *kn)
655 static inline void sysfs_put(struct kernfs_node *kn)
660 #endif /* _SYSFS_H_ */