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/spinlock.h>
24#include <linux/rwsem.h>
25#include <linux/kref.h>
26#include <linux/kobject_uevent.h>
27#include <linux/kernel.h>
28#include <asm/atomic.h>
29
30#define KOBJ_NAME_LEN 20
31
32/* counter to tag the hotplug event, read only except for the kobject core */
33extern u64 hotplug_seqnum;
34
35struct kobject {
36 char * k_name;
37 char name[KOBJ_NAME_LEN];
38 struct kref kref;
39 struct list_head entry;
40 struct kobject * parent;
41 struct kset * kset;
42 struct kobj_type * ktype;
43 struct dentry * dentry;
44};
45
46extern int kobject_set_name(struct kobject *, const char *, ...)
47 __attribute__((format(printf,2,3)));
48
49static inline char * kobject_name(struct kobject * kobj)
50{
51 return kobj->k_name;
52}
53
54extern void kobject_init(struct kobject *);
55extern void kobject_cleanup(struct kobject *);
56
57extern int kobject_add(struct kobject *);
58extern void kobject_del(struct kobject *);
59
60extern int kobject_rename(struct kobject *, char *new_name);
61
62extern int kobject_register(struct kobject *);
63extern void kobject_unregister(struct kobject *);
64
65extern struct kobject * kobject_get(struct kobject *);
66extern void kobject_put(struct kobject *);
67
68extern char * kobject_get_path(struct kobject *, int);
69
70struct kobj_type {
71 void (*release)(struct kobject *);
72 struct sysfs_ops * sysfs_ops;
73 struct attribute ** default_attrs;
74};
75
76
77/**
78 * kset - a set of kobjects of a specific type, belonging
79 * to a specific subsystem.
80 *
81 * All kobjects of a kset should be embedded in an identical
82 * type. This type may have a descriptor, which the kset points
83 * to. This allows there to exist sets of objects of the same
84 * type in different subsystems.
85 *
86 * A subsystem does not have to be a list of only one type
87 * of object; multiple ksets can belong to one subsystem. All
88 * ksets of a subsystem share the subsystem's lock.
89 *
90 * Each kset can support hotplugging; if it does, it will be given
91 * the opportunity to filter out specific kobjects from being
92 * reported, as well as to add its own "data" elements to the
93 * environment being passed to the hotplug helper.
94 */
95struct kset_hotplug_ops {
96 int (*filter)(struct kset *kset, struct kobject *kobj);
97 char *(*name)(struct kset *kset, struct kobject *kobj);
98 int (*hotplug)(struct kset *kset, struct kobject *kobj, char **envp,
99 int num_envp, char *buffer, int buffer_size);
100};
101
102struct kset {
103 struct subsystem * subsys;
104 struct kobj_type * ktype;
105 struct list_head list;
106 spinlock_t list_lock;
107 struct kobject kobj;
108 struct kset_hotplug_ops * hotplug_ops;
109};
110
111
112extern void kset_init(struct kset * k);
113extern int kset_add(struct kset * k);
114extern int kset_register(struct kset * k);
115extern void kset_unregister(struct kset * k);
116
117static inline struct kset * to_kset(struct kobject * kobj)
118{
119 return kobj ? container_of(kobj,struct kset,kobj) : NULL;
120}
121
122static inline struct kset * kset_get(struct kset * k)
123{
124 return k ? to_kset(kobject_get(&k->kobj)) : NULL;
125}
126
127static inline void kset_put(struct kset * k)
128{
129 kobject_put(&k->kobj);
130}
131
132static inline struct kobj_type * get_ktype(struct kobject * k)
133{
134 if (k->kset && k->kset->ktype)
135 return k->kset->ktype;
136 else
137 return k->ktype;
138}
139
140extern struct kobject * kset_find_obj(struct kset *, const char *);
141
142
143/**
144 * Use this when initializing an embedded kset with no other
145 * fields to initialize.
146 */
147#define set_kset_name(str) .kset = { .kobj = { .name = str } }
148
149
150
151struct subsystem {
152 struct kset kset;
153 struct rw_semaphore rwsem;
154};
155
156#define decl_subsys(_name,_type,_hotplug_ops) \
157struct subsystem _name##_subsys = { \
158 .kset = { \
159 .kobj = { .name = __stringify(_name) }, \
160 .ktype = _type, \
161 .hotplug_ops =_hotplug_ops, \
162 } \
163}
164#define decl_subsys_name(_varname,_name,_type,_hotplug_ops) \
165struct subsystem _varname##_subsys = { \
166 .kset = { \
167 .kobj = { .name = __stringify(_name) }, \
168 .ktype = _type, \
169 .hotplug_ops =_hotplug_ops, \
170 } \
171}
172
173/* The global /sys/kernel/ subsystem for people to chain off of */
174extern struct subsystem kernel_subsys;
175
176/**
177 * Helpers for setting the kset of registered objects.
178 * Often, a registered object belongs to a kset embedded in a
179 * subsystem. These do no magic, just make the resulting code
180 * easier to follow.
181 */
182
183/**
184 * kobj_set_kset_s(obj,subsys) - set kset for embedded kobject.
185 * @obj: ptr to some object type.
186 * @subsys: a subsystem object (not a ptr).
187 *
188 * Can be used for any object type with an embedded ->kobj.
189 */
190
191#define kobj_set_kset_s(obj,subsys) \
192 (obj)->kobj.kset = &(subsys).kset
193
194/**
195 * kset_set_kset_s(obj,subsys) - set kset for embedded kset.
196 * @obj: ptr to some object type.
197 * @subsys: a subsystem object (not a ptr).
198 *
199 * Can be used for any object type with an embedded ->kset.
200 * Sets the kset of @obj's embedded kobject (via its embedded
201 * kset) to @subsys.kset. This makes @obj a member of that
202 * kset.
203 */
204
205#define kset_set_kset_s(obj,subsys) \
206 (obj)->kset.kobj.kset = &(subsys).kset
207
208/**
209 * subsys_set_kset(obj,subsys) - set kset for subsystem
210 * @obj: ptr to some object type.
211 * @subsys: a subsystem object (not a ptr).
212 *
213 * Can be used for any object type with an embedded ->subsys.
214 * Sets the kset of @obj's kobject to @subsys.kset. This makes
215 * the object a member of that kset.
216 */
217
218#define subsys_set_kset(obj,_subsys) \
219 (obj)->subsys.kset.kobj.kset = &(_subsys).kset
220
221extern void subsystem_init(struct subsystem *);
222extern int subsystem_register(struct subsystem *);
223extern void subsystem_unregister(struct subsystem *);
224
225static inline struct subsystem * subsys_get(struct subsystem * s)
226{
227 return s ? container_of(kset_get(&s->kset),struct subsystem,kset) : NULL;
228}
229
230static inline void subsys_put(struct subsystem * s)
231{
232 kset_put(&s->kset);
233}
234
235struct subsys_attribute {
236 struct attribute attr;
237 ssize_t (*show)(struct subsystem *, char *);
238 ssize_t (*store)(struct subsystem *, const char *, size_t);
239};
240
241extern int subsys_create_file(struct subsystem * , struct subsys_attribute *);
242extern void subsys_remove_file(struct subsystem * , struct subsys_attribute *);
243
244#ifdef CONFIG_HOTPLUG
245void kobject_hotplug(struct kobject *kobj, enum kobject_action action);
246int add_hotplug_env_var(char **envp, int num_envp, int *cur_index,
247 char *buffer, int buffer_size, int *cur_len,
248 const char *format, ...)
249 __attribute__((format (printf, 7, 8)));
250#else
251static inline void kobject_hotplug(struct kobject *kobj, enum kobject_action action) { }
252static inline int add_hotplug_env_var(char **envp, int num_envp, int *cur_index,
253 char *buffer, int buffer_size, int *cur_len,
254 const char *format, ...)
255{ return 0; }
256#endif
257
258#endif /* __KERNEL__ */
259#endif /* _KOBJECT_H_ */