2 * kobject.h - generic kernel object infrastructure.
4 * Copyright (c) 2002-2003 Patrick Mochel
5 * Copyright (c) 2002-2003 Open Source Development Labs
7 * This file is released under the GPLv2.
10 * Please read Documentation/kobject.txt before using the kobject
11 * interface, ESPECIALLY the parts about reference counts and object
20 #include <linux/types.h>
21 #include <linux/list.h>
22 #include <linux/sysfs.h>
23 #include <linux/compiler.h>
24 #include <linux/spinlock.h>
25 #include <linux/rwsem.h>
26 #include <linux/kref.h>
27 #include <linux/kernel.h>
28 #include <linux/wait.h>
29 #include <asm/atomic.h>
31 #define KOBJ_NAME_LEN 20
32 #define UEVENT_HELPER_PATH_LEN 256
34 /* path to the userspace helper executed on an event */
35 extern char uevent_helper
[];
37 /* counter to tag the uevent, read only except for the kobject core */
38 extern u64 uevent_seqnum
;
40 /* the actions here must match the proper string in lib/kobject_uevent.c */
41 typedef int __bitwise kobject_action_t
;
43 KOBJ_ADD
= (__force kobject_action_t
) 0x01, /* exclusive to core */
44 KOBJ_REMOVE
= (__force kobject_action_t
) 0x02, /* exclusive to core */
45 KOBJ_CHANGE
= (__force kobject_action_t
) 0x03, /* device state change */
46 KOBJ_MOUNT
= (__force kobject_action_t
) 0x04, /* mount event for block devices (broken) */
47 KOBJ_UMOUNT
= (__force kobject_action_t
) 0x05, /* umount event for block devices (broken) */
48 KOBJ_OFFLINE
= (__force kobject_action_t
) 0x06, /* device offline */
49 KOBJ_ONLINE
= (__force kobject_action_t
) 0x07, /* device online */
50 KOBJ_MOVE
= (__force kobject_action_t
) 0x08, /* device move */
55 char name
[KOBJ_NAME_LEN
];
57 struct list_head entry
;
58 struct kobject
* parent
;
60 struct kobj_type
* ktype
;
61 struct dentry
* dentry
;
62 wait_queue_head_t poll
;
65 extern int kobject_set_name(struct kobject
*, const char *, ...)
66 __attribute__((format(printf
,2,3)));
68 static inline const char * kobject_name(const struct kobject
* kobj
)
73 extern void kobject_init(struct kobject
*);
74 extern void kobject_cleanup(struct kobject
*);
76 extern int __must_check
kobject_add(struct kobject
*);
77 extern void kobject_del(struct kobject
*);
79 extern int __must_check
kobject_rename(struct kobject
*, const char *new_name
);
80 extern int __must_check
kobject_move(struct kobject
*, struct kobject
*);
82 extern int __must_check
kobject_register(struct kobject
*);
83 extern void kobject_unregister(struct kobject
*);
85 extern struct kobject
* kobject_get(struct kobject
*);
86 extern void kobject_put(struct kobject
*);
88 extern struct kobject
*kobject_add_dir(struct kobject
*, const char *);
90 extern char * kobject_get_path(struct kobject
*, gfp_t
);
93 void (*release
)(struct kobject
*);
94 struct sysfs_ops
* sysfs_ops
;
95 struct attribute
** default_attrs
;
100 * kset - a set of kobjects of a specific type, belonging
101 * to a specific subsystem.
103 * All kobjects of a kset should be embedded in an identical
104 * type. This type may have a descriptor, which the kset points
105 * to. This allows there to exist sets of objects of the same
106 * type in different subsystems.
108 * A subsystem does not have to be a list of only one type
109 * of object; multiple ksets can belong to one subsystem. All
110 * ksets of a subsystem share the subsystem's lock.
112 * Each kset can support specific event variables; it can
113 * supress the event generation or add subsystem specific
114 * variables carried with the event.
116 struct kset_uevent_ops
{
117 int (*filter
)(struct kset
*kset
, struct kobject
*kobj
);
118 const char *(*name
)(struct kset
*kset
, struct kobject
*kobj
);
119 int (*uevent
)(struct kset
*kset
, struct kobject
*kobj
, char **envp
,
120 int num_envp
, char *buffer
, int buffer_size
);
124 struct subsystem
* subsys
;
125 struct kobj_type
* ktype
;
126 struct list_head list
;
127 spinlock_t list_lock
;
129 struct kset_uevent_ops
* uevent_ops
;
133 extern void kset_init(struct kset
* k
);
134 extern int __must_check
kset_add(struct kset
* k
);
135 extern int __must_check
kset_register(struct kset
* k
);
136 extern void kset_unregister(struct kset
* k
);
138 static inline struct kset
* to_kset(struct kobject
* kobj
)
140 return kobj
? container_of(kobj
,struct kset
,kobj
) : NULL
;
143 static inline struct kset
* kset_get(struct kset
* k
)
145 return k
? to_kset(kobject_get(&k
->kobj
)) : NULL
;
148 static inline void kset_put(struct kset
* k
)
150 kobject_put(&k
->kobj
);
153 static inline struct kobj_type
* get_ktype(struct kobject
* k
)
155 if (k
->kset
&& k
->kset
->ktype
)
156 return k
->kset
->ktype
;
161 extern struct kobject
* kset_find_obj(struct kset
*, const char *);
165 * Use this when initializing an embedded kset with no other
166 * fields to initialize.
168 #define set_kset_name(str) .kset = { .kobj = { .name = str } }
174 struct rw_semaphore rwsem
;
177 #define decl_subsys(_name,_type,_uevent_ops) \
178 struct subsystem _name##_subsys = { \
180 .kobj = { .name = __stringify(_name) }, \
182 .uevent_ops =_uevent_ops, \
185 #define decl_subsys_name(_varname,_name,_type,_uevent_ops) \
186 struct subsystem _varname##_subsys = { \
188 .kobj = { .name = __stringify(_name) }, \
190 .uevent_ops =_uevent_ops, \
194 /* The global /sys/kernel/ subsystem for people to chain off of */
195 extern struct subsystem kernel_subsys
;
196 /* The global /sys/hypervisor/ subsystem */
197 extern struct subsystem hypervisor_subsys
;
200 * Helpers for setting the kset of registered objects.
201 * Often, a registered object belongs to a kset embedded in a
202 * subsystem. These do no magic, just make the resulting code
207 * kobj_set_kset_s(obj,subsys) - set kset for embedded kobject.
208 * @obj: ptr to some object type.
209 * @subsys: a subsystem object (not a ptr).
211 * Can be used for any object type with an embedded ->kobj.
214 #define kobj_set_kset_s(obj,subsys) \
215 (obj)->kobj.kset = &(subsys).kset
218 * kset_set_kset_s(obj,subsys) - set kset for embedded kset.
219 * @obj: ptr to some object type.
220 * @subsys: a subsystem object (not a ptr).
222 * Can be used for any object type with an embedded ->kset.
223 * Sets the kset of @obj's embedded kobject (via its embedded
224 * kset) to @subsys.kset. This makes @obj a member of that
228 #define kset_set_kset_s(obj,subsys) \
229 (obj)->kset.kobj.kset = &(subsys).kset
232 * subsys_set_kset(obj,subsys) - set kset for subsystem
233 * @obj: ptr to some object type.
234 * @subsys: a subsystem object (not a ptr).
236 * Can be used for any object type with an embedded ->subsys.
237 * Sets the kset of @obj's kobject to @subsys.kset. This makes
238 * the object a member of that kset.
241 #define subsys_set_kset(obj,_subsys) \
242 (obj)->subsys.kset.kobj.kset = &(_subsys).kset
244 extern void subsystem_init(struct subsystem
*);
245 extern int __must_check
subsystem_register(struct subsystem
*);
246 extern void subsystem_unregister(struct subsystem
*);
248 static inline struct subsystem
* subsys_get(struct subsystem
* s
)
250 return s
? container_of(kset_get(&s
->kset
),struct subsystem
,kset
) : NULL
;
253 static inline void subsys_put(struct subsystem
* s
)
258 struct subsys_attribute
{
259 struct attribute attr
;
260 ssize_t (*show
)(struct subsystem
*, char *);
261 ssize_t (*store
)(struct subsystem
*, const char *, size_t);
264 extern int __must_check
subsys_create_file(struct subsystem
* ,
265 struct subsys_attribute
*);
267 #if defined(CONFIG_HOTPLUG)
268 void kobject_uevent(struct kobject
*kobj
, enum kobject_action action
);
269 void kobject_uevent_env(struct kobject
*kobj
, enum kobject_action action
,
272 int add_uevent_var(char **envp
, int num_envp
, int *cur_index
,
273 char *buffer
, int buffer_size
, int *cur_len
,
274 const char *format
, ...)
275 __attribute__((format (printf
, 7, 8)));
277 static inline void kobject_uevent(struct kobject
*kobj
, enum kobject_action action
) { }
278 static inline void kobject_uevent_env(struct kobject
*kobj
,
279 enum kobject_action action
,
283 static inline int add_uevent_var(char **envp
, int num_envp
, int *cur_index
,
284 char *buffer
, int buffer_size
, int *cur_len
,
285 const char *format
, ...)
289 #endif /* __KERNEL__ */
290 #endif /* _KOBJECT_H_ */