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/spinlock.h>
24 #include <linux/rwsem.h>
25 #include <linux/kref.h>
26 #include <linux/kernel.h>
27 #include <linux/wait.h>
28 #include <asm/atomic.h>
30 #define KOBJ_NAME_LEN 20
31 #define UEVENT_HELPER_PATH_LEN 256
33 /* path to the userspace helper executed on an event */
34 extern char uevent_helper
[];
36 /* counter to tag the uevent, read only except for the kobject core */
37 extern u64 uevent_seqnum
;
39 /* the actions here must match the proper string in lib/kobject_uevent.c */
40 typedef int __bitwise kobject_action_t
;
42 KOBJ_ADD
= (__force kobject_action_t
) 0x01, /* exclusive to core */
43 KOBJ_REMOVE
= (__force kobject_action_t
) 0x02, /* exclusive to core */
44 KOBJ_CHANGE
= (__force kobject_action_t
) 0x03, /* device state change */
45 KOBJ_MOUNT
= (__force kobject_action_t
) 0x04, /* mount event for block devices (broken) */
46 KOBJ_UMOUNT
= (__force kobject_action_t
) 0x05, /* umount event for block devices (broken) */
47 KOBJ_OFFLINE
= (__force kobject_action_t
) 0x06, /* device offline */
48 KOBJ_ONLINE
= (__force kobject_action_t
) 0x07, /* device online */
53 char name
[KOBJ_NAME_LEN
];
55 struct list_head entry
;
56 struct kobject
* parent
;
58 struct kobj_type
* ktype
;
59 struct dentry
* dentry
;
60 wait_queue_head_t poll
;
63 extern int kobject_set_name(struct kobject
*, const char *, ...)
64 __attribute__((format(printf
,2,3)));
66 static inline const char * kobject_name(const struct kobject
* kobj
)
71 extern void kobject_init(struct kobject
*);
72 extern void kobject_cleanup(struct kobject
*);
74 extern int kobject_add(struct kobject
*);
75 extern void kobject_del(struct kobject
*);
77 extern int kobject_rename(struct kobject
*, const char *new_name
);
79 extern int kobject_register(struct kobject
*);
80 extern void kobject_unregister(struct kobject
*);
82 extern struct kobject
* kobject_get(struct kobject
*);
83 extern void kobject_put(struct kobject
*);
85 extern struct kobject
*kobject_add_dir(struct kobject
*, const char *);
87 extern char * kobject_get_path(struct kobject
*, gfp_t
);
90 void (*release
)(struct kobject
*);
91 struct sysfs_ops
* sysfs_ops
;
92 struct attribute
** default_attrs
;
97 * kset - a set of kobjects of a specific type, belonging
98 * to a specific subsystem.
100 * All kobjects of a kset should be embedded in an identical
101 * type. This type may have a descriptor, which the kset points
102 * to. This allows there to exist sets of objects of the same
103 * type in different subsystems.
105 * A subsystem does not have to be a list of only one type
106 * of object; multiple ksets can belong to one subsystem. All
107 * ksets of a subsystem share the subsystem's lock.
109 * Each kset can support specific event variables; it can
110 * supress the event generation or add subsystem specific
111 * variables carried with the event.
113 struct kset_uevent_ops
{
114 int (*filter
)(struct kset
*kset
, struct kobject
*kobj
);
115 const char *(*name
)(struct kset
*kset
, struct kobject
*kobj
);
116 int (*uevent
)(struct kset
*kset
, struct kobject
*kobj
, char **envp
,
117 int num_envp
, char *buffer
, int buffer_size
);
121 struct subsystem
* subsys
;
122 struct kobj_type
* ktype
;
123 struct list_head list
;
124 spinlock_t list_lock
;
126 struct kset_uevent_ops
* uevent_ops
;
130 extern void kset_init(struct kset
* k
);
131 extern int kset_add(struct kset
* k
);
132 extern int kset_register(struct kset
* k
);
133 extern void kset_unregister(struct kset
* k
);
135 static inline struct kset
* to_kset(struct kobject
* kobj
)
137 return kobj
? container_of(kobj
,struct kset
,kobj
) : NULL
;
140 static inline struct kset
* kset_get(struct kset
* k
)
142 return k
? to_kset(kobject_get(&k
->kobj
)) : NULL
;
145 static inline void kset_put(struct kset
* k
)
147 kobject_put(&k
->kobj
);
150 static inline struct kobj_type
* get_ktype(struct kobject
* k
)
152 if (k
->kset
&& k
->kset
->ktype
)
153 return k
->kset
->ktype
;
158 extern struct kobject
* kset_find_obj(struct kset
*, const char *);
162 * Use this when initializing an embedded kset with no other
163 * fields to initialize.
165 #define set_kset_name(str) .kset = { .kobj = { .name = str } }
171 struct rw_semaphore rwsem
;
174 #define decl_subsys(_name,_type,_uevent_ops) \
175 struct subsystem _name##_subsys = { \
177 .kobj = { .name = __stringify(_name) }, \
179 .uevent_ops =_uevent_ops, \
182 #define decl_subsys_name(_varname,_name,_type,_uevent_ops) \
183 struct subsystem _varname##_subsys = { \
185 .kobj = { .name = __stringify(_name) }, \
187 .uevent_ops =_uevent_ops, \
191 /* The global /sys/kernel/ subsystem for people to chain off of */
192 extern struct subsystem kernel_subsys
;
195 * Helpers for setting the kset of registered objects.
196 * Often, a registered object belongs to a kset embedded in a
197 * subsystem. These do no magic, just make the resulting code
202 * kobj_set_kset_s(obj,subsys) - set kset for embedded kobject.
203 * @obj: ptr to some object type.
204 * @subsys: a subsystem object (not a ptr).
206 * Can be used for any object type with an embedded ->kobj.
209 #define kobj_set_kset_s(obj,subsys) \
210 (obj)->kobj.kset = &(subsys).kset
213 * kset_set_kset_s(obj,subsys) - set kset for embedded kset.
214 * @obj: ptr to some object type.
215 * @subsys: a subsystem object (not a ptr).
217 * Can be used for any object type with an embedded ->kset.
218 * Sets the kset of @obj's embedded kobject (via its embedded
219 * kset) to @subsys.kset. This makes @obj a member of that
223 #define kset_set_kset_s(obj,subsys) \
224 (obj)->kset.kobj.kset = &(subsys).kset
227 * subsys_set_kset(obj,subsys) - set kset for subsystem
228 * @obj: ptr to some object type.
229 * @subsys: a subsystem object (not a ptr).
231 * Can be used for any object type with an embedded ->subsys.
232 * Sets the kset of @obj's kobject to @subsys.kset. This makes
233 * the object a member of that kset.
236 #define subsys_set_kset(obj,_subsys) \
237 (obj)->subsys.kset.kobj.kset = &(_subsys).kset
239 extern void subsystem_init(struct subsystem
*);
240 extern int subsystem_register(struct subsystem
*);
241 extern void subsystem_unregister(struct subsystem
*);
243 static inline struct subsystem
* subsys_get(struct subsystem
* s
)
245 return s
? container_of(kset_get(&s
->kset
),struct subsystem
,kset
) : NULL
;
248 static inline void subsys_put(struct subsystem
* s
)
253 struct subsys_attribute
{
254 struct attribute attr
;
255 ssize_t (*show
)(struct subsystem
*, char *);
256 ssize_t (*store
)(struct subsystem
*, const char *, size_t);
259 extern int subsys_create_file(struct subsystem
* , struct subsys_attribute
*);
261 #if defined(CONFIG_HOTPLUG)
262 void kobject_uevent(struct kobject
*kobj
, enum kobject_action action
);
264 int add_uevent_var(char **envp
, int num_envp
, int *cur_index
,
265 char *buffer
, int buffer_size
, int *cur_len
,
266 const char *format
, ...)
267 __attribute__((format (printf
, 7, 8)));
269 static inline void kobject_uevent(struct kobject
*kobj
, enum kobject_action action
) { }
271 static inline int add_uevent_var(char **envp
, int num_envp
, int *cur_index
,
272 char *buffer
, int buffer_size
, int *cur_len
,
273 const char *format
, ...)
277 #endif /* __KERNEL__ */
278 #endif /* _KOBJECT_H_ */