Linux kernel mirror (for testing)
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1/*
2 * kobject.h - generic kernel object infrastructure.
3 *
4 * Copyright (c) 2002-2003 Patrick Mochel
5 * Copyright (c) 2002-2003 Open Source Development Labs
6 *
7 * This file is released under the GPLv2.
8 *
9 *
10 * Please read Documentation/kobject.txt before using the kobject
11 * interface, ESPECIALLY the parts about reference counts and object
12 * destructors.
13 */
14
15#ifndef _KOBJECT_H_
16#define _KOBJECT_H_
17
18#ifdef __KERNEL__
19
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>
30
31#define KOBJ_NAME_LEN 20
32#define UEVENT_HELPER_PATH_LEN 256
33
34/* path to the userspace helper executed on an event */
35extern char uevent_helper[];
36
37/* counter to tag the uevent, read only except for the kobject core */
38extern u64 uevent_seqnum;
39
40/* the actions here must match the proper string in lib/kobject_uevent.c */
41typedef int __bitwise kobject_action_t;
42enum kobject_action {
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 */
51};
52
53struct kobject {
54 const char * k_name;
55 char name[KOBJ_NAME_LEN];
56 struct kref kref;
57 struct list_head entry;
58 struct kobject * parent;
59 struct kset * kset;
60 struct kobj_type * ktype;
61 struct dentry * dentry;
62 wait_queue_head_t poll;
63};
64
65extern int kobject_set_name(struct kobject *, const char *, ...)
66 __attribute__((format(printf,2,3)));
67
68static inline const char * kobject_name(const struct kobject * kobj)
69{
70 return kobj->k_name;
71}
72
73extern void kobject_init(struct kobject *);
74extern void kobject_cleanup(struct kobject *);
75
76extern int __must_check kobject_add(struct kobject *);
77extern int __must_check kobject_shadow_add(struct kobject *, struct dentry *);
78extern void kobject_del(struct kobject *);
79
80extern int __must_check kobject_rename(struct kobject *, const char *new_name);
81extern int __must_check kobject_shadow_rename(struct kobject *kobj,
82 struct dentry *new_parent,
83 const char *new_name);
84extern int __must_check kobject_move(struct kobject *, struct kobject *);
85
86extern int __must_check kobject_register(struct kobject *);
87extern void kobject_unregister(struct kobject *);
88
89extern struct kobject * kobject_get(struct kobject *);
90extern void kobject_put(struct kobject *);
91
92extern struct kobject *kobject_add_dir(struct kobject *, const char *);
93
94extern char * kobject_get_path(struct kobject *, gfp_t);
95
96struct kobj_type {
97 void (*release)(struct kobject *);
98 struct sysfs_ops * sysfs_ops;
99 struct attribute ** default_attrs;
100};
101
102
103/**
104 * kset - a set of kobjects of a specific type, belonging
105 * to a specific subsystem.
106 *
107 * All kobjects of a kset should be embedded in an identical
108 * type. This type may have a descriptor, which the kset points
109 * to. This allows there to exist sets of objects of the same
110 * type in different subsystems.
111 *
112 * A subsystem does not have to be a list of only one type
113 * of object; multiple ksets can belong to one subsystem. All
114 * ksets of a subsystem share the subsystem's lock.
115 *
116 * Each kset can support specific event variables; it can
117 * supress the event generation or add subsystem specific
118 * variables carried with the event.
119 */
120struct kset_uevent_ops {
121 int (*filter)(struct kset *kset, struct kobject *kobj);
122 const char *(*name)(struct kset *kset, struct kobject *kobj);
123 int (*uevent)(struct kset *kset, struct kobject *kobj, char **envp,
124 int num_envp, char *buffer, int buffer_size);
125};
126
127struct kset {
128 struct subsystem * subsys;
129 struct kobj_type * ktype;
130 struct list_head list;
131 spinlock_t list_lock;
132 struct kobject kobj;
133 struct kset_uevent_ops * uevent_ops;
134};
135
136
137extern void kset_init(struct kset * k);
138extern int __must_check kset_add(struct kset * k);
139extern int __must_check kset_register(struct kset * k);
140extern void kset_unregister(struct kset * k);
141
142static inline struct kset * to_kset(struct kobject * kobj)
143{
144 return kobj ? container_of(kobj,struct kset,kobj) : NULL;
145}
146
147static inline struct kset * kset_get(struct kset * k)
148{
149 return k ? to_kset(kobject_get(&k->kobj)) : NULL;
150}
151
152static inline void kset_put(struct kset * k)
153{
154 kobject_put(&k->kobj);
155}
156
157static inline struct kobj_type * get_ktype(struct kobject * k)
158{
159 if (k->kset && k->kset->ktype)
160 return k->kset->ktype;
161 else
162 return k->ktype;
163}
164
165extern struct kobject * kset_find_obj(struct kset *, const char *);
166
167
168/**
169 * Use this when initializing an embedded kset with no other
170 * fields to initialize.
171 */
172#define set_kset_name(str) .kset = { .kobj = { .name = str } }
173
174
175
176struct subsystem {
177 struct kset kset;
178 struct rw_semaphore rwsem;
179};
180
181#define decl_subsys(_name,_type,_uevent_ops) \
182struct subsystem _name##_subsys = { \
183 .kset = { \
184 .kobj = { .name = __stringify(_name) }, \
185 .ktype = _type, \
186 .uevent_ops =_uevent_ops, \
187 } \
188}
189#define decl_subsys_name(_varname,_name,_type,_uevent_ops) \
190struct subsystem _varname##_subsys = { \
191 .kset = { \
192 .kobj = { .name = __stringify(_name) }, \
193 .ktype = _type, \
194 .uevent_ops =_uevent_ops, \
195 } \
196}
197
198/* The global /sys/kernel/ subsystem for people to chain off of */
199extern struct subsystem kernel_subsys;
200/* The global /sys/hypervisor/ subsystem */
201extern struct subsystem hypervisor_subsys;
202
203/**
204 * Helpers for setting the kset of registered objects.
205 * Often, a registered object belongs to a kset embedded in a
206 * subsystem. These do no magic, just make the resulting code
207 * easier to follow.
208 */
209
210/**
211 * kobj_set_kset_s(obj,subsys) - set kset for embedded kobject.
212 * @obj: ptr to some object type.
213 * @subsys: a subsystem object (not a ptr).
214 *
215 * Can be used for any object type with an embedded ->kobj.
216 */
217
218#define kobj_set_kset_s(obj,subsys) \
219 (obj)->kobj.kset = &(subsys).kset
220
221/**
222 * kset_set_kset_s(obj,subsys) - set kset for embedded kset.
223 * @obj: ptr to some object type.
224 * @subsys: a subsystem object (not a ptr).
225 *
226 * Can be used for any object type with an embedded ->kset.
227 * Sets the kset of @obj's embedded kobject (via its embedded
228 * kset) to @subsys.kset. This makes @obj a member of that
229 * kset.
230 */
231
232#define kset_set_kset_s(obj,subsys) \
233 (obj)->kset.kobj.kset = &(subsys).kset
234
235/**
236 * subsys_set_kset(obj,subsys) - set kset for subsystem
237 * @obj: ptr to some object type.
238 * @subsys: a subsystem object (not a ptr).
239 *
240 * Can be used for any object type with an embedded ->subsys.
241 * Sets the kset of @obj's kobject to @subsys.kset. This makes
242 * the object a member of that kset.
243 */
244
245#define subsys_set_kset(obj,_subsys) \
246 (obj)->subsys.kset.kobj.kset = &(_subsys).kset
247
248extern void subsystem_init(struct subsystem *);
249extern int __must_check subsystem_register(struct subsystem *);
250extern void subsystem_unregister(struct subsystem *);
251
252static inline struct subsystem * subsys_get(struct subsystem * s)
253{
254 return s ? container_of(kset_get(&s->kset),struct subsystem,kset) : NULL;
255}
256
257static inline void subsys_put(struct subsystem * s)
258{
259 kset_put(&s->kset);
260}
261
262struct subsys_attribute {
263 struct attribute attr;
264 ssize_t (*show)(struct subsystem *, char *);
265 ssize_t (*store)(struct subsystem *, const char *, size_t);
266};
267
268extern int __must_check subsys_create_file(struct subsystem * ,
269 struct subsys_attribute *);
270
271#if defined(CONFIG_HOTPLUG)
272int kobject_uevent(struct kobject *kobj, enum kobject_action action);
273int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
274 char *envp[]);
275
276int add_uevent_var(char **envp, int num_envp, int *cur_index,
277 char *buffer, int buffer_size, int *cur_len,
278 const char *format, ...)
279 __attribute__((format (printf, 7, 8)));
280#else
281static inline int kobject_uevent(struct kobject *kobj, enum kobject_action action)
282{ return 0; }
283static inline int kobject_uevent_env(struct kobject *kobj,
284 enum kobject_action action,
285 char *envp[])
286{ return 0; }
287
288static inline int add_uevent_var(char **envp, int num_envp, int *cur_index,
289 char *buffer, int buffer_size, int *cur_len,
290 const char *format, ...)
291{ return 0; }
292#endif
293
294#endif /* __KERNEL__ */
295#endif /* _KOBJECT_H_ */