Linux kernel mirror (for testing)
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linux
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/kref.h>
26#include <linux/kernel.h>
27#include <linux/wait.h>
28#include <asm/atomic.h>
29
30#define KOBJ_NAME_LEN 20
31#define UEVENT_HELPER_PATH_LEN 256
32
33/* path to the userspace helper executed on an event */
34extern char uevent_helper[];
35
36/* counter to tag the uevent, read only except for the kobject core */
37extern u64 uevent_seqnum;
38
39/*
40 * The actions here must match the index to the string array
41 * in lib/kobject_uevent.c
42 *
43 * Do not add new actions here without checking with the driver-core
44 * maintainers. Action strings are not meant to express subsystem
45 * or device specific properties. In most cases you want to send a
46 * kobject_uevent_env(kobj, KOBJ_CHANGE, env) with additional event
47 * specific variables added to the event environment.
48 */
49enum kobject_action {
50 KOBJ_ADD,
51 KOBJ_REMOVE,
52 KOBJ_CHANGE,
53 KOBJ_MOVE,
54 KOBJ_ONLINE,
55 KOBJ_OFFLINE,
56 KOBJ_MAX
57};
58
59/* The list of strings defining the valid kobject actions as specified above */
60extern const char *kobject_actions[];
61
62struct kobject {
63 const char * k_name;
64 char name[KOBJ_NAME_LEN];
65 struct kref kref;
66 struct list_head entry;
67 struct kobject * parent;
68 struct kset * kset;
69 struct kobj_type * ktype;
70 struct sysfs_dirent * sd;
71 wait_queue_head_t poll;
72};
73
74extern int kobject_set_name(struct kobject *, const char *, ...)
75 __attribute__((format(printf,2,3)));
76
77static inline const char * kobject_name(const struct kobject * kobj)
78{
79 return kobj->k_name;
80}
81
82extern void kobject_init(struct kobject *);
83extern void kobject_cleanup(struct kobject *);
84
85extern int __must_check kobject_add(struct kobject *);
86extern int __must_check kobject_shadow_add(struct kobject *kobj,
87 struct sysfs_dirent *shadow_parent);
88extern void kobject_del(struct kobject *);
89
90extern int __must_check kobject_rename(struct kobject *, const char *new_name);
91extern int __must_check kobject_shadow_rename(struct kobject *kobj,
92 struct sysfs_dirent *new_parent,
93 const char *new_name);
94extern int __must_check kobject_move(struct kobject *, struct kobject *);
95
96extern int __must_check kobject_register(struct kobject *);
97extern void kobject_unregister(struct kobject *);
98
99extern struct kobject * kobject_get(struct kobject *);
100extern void kobject_put(struct kobject *);
101
102extern struct kobject *kobject_kset_add_dir(struct kset *kset,
103 struct kobject *, const char *);
104extern struct kobject *kobject_add_dir(struct kobject *, const char *);
105
106extern char * kobject_get_path(struct kobject *, gfp_t);
107
108struct kobj_type {
109 void (*release)(struct kobject *);
110 struct sysfs_ops * sysfs_ops;
111 struct attribute ** default_attrs;
112};
113
114struct kset_uevent_ops {
115 int (*filter)(struct kset *kset, struct kobject *kobj);
116 const char *(*name)(struct kset *kset, struct kobject *kobj);
117 int (*uevent)(struct kset *kset, struct kobject *kobj, char **envp,
118 int num_envp, char *buffer, int buffer_size);
119};
120
121/*
122 * struct kset - a set of kobjects of a specific type, belonging
123 * to a specific subsystem.
124 *
125 * All kobjects of a kset should be embedded in an identical
126 * type. This type may have a descriptor, which the kset points
127 * to. This allows there to exist sets of objects of the same
128 * type in different subsystems.
129 *
130 * A subsystem does not have to be a list of only one type
131 * of object; multiple ksets can belong to one subsystem. All
132 * ksets of a subsystem share the subsystem's lock.
133 *
134 * Each kset can support specific event variables; it can
135 * supress the event generation or add subsystem specific
136 * variables carried with the event.
137 */
138struct kset {
139 struct kobj_type * ktype;
140 struct list_head list;
141 spinlock_t list_lock;
142 struct kobject kobj;
143 struct kset_uevent_ops * uevent_ops;
144};
145
146
147extern void kset_init(struct kset * k);
148extern int __must_check kset_add(struct kset * k);
149extern int __must_check kset_register(struct kset * k);
150extern void kset_unregister(struct kset * k);
151
152static inline struct kset * to_kset(struct kobject * kobj)
153{
154 return kobj ? container_of(kobj,struct kset,kobj) : NULL;
155}
156
157static inline struct kset * kset_get(struct kset * k)
158{
159 return k ? to_kset(kobject_get(&k->kobj)) : NULL;
160}
161
162static inline void kset_put(struct kset * k)
163{
164 kobject_put(&k->kobj);
165}
166
167static inline struct kobj_type * get_ktype(struct kobject * k)
168{
169 if (k->kset && k->kset->ktype)
170 return k->kset->ktype;
171 else
172 return k->ktype;
173}
174
175extern struct kobject * kset_find_obj(struct kset *, const char *);
176
177
178/*
179 * Use this when initializing an embedded kset with no other
180 * fields to initialize.
181 */
182#define set_kset_name(str) .kset = { .kobj = { .name = str } }
183
184
185#define decl_subsys(_name,_type,_uevent_ops) \
186struct kset _name##_subsys = { \
187 .kobj = { .name = __stringify(_name) }, \
188 .ktype = _type, \
189 .uevent_ops =_uevent_ops, \
190}
191#define decl_subsys_name(_varname,_name,_type,_uevent_ops) \
192struct kset _varname##_subsys = { \
193 .kobj = { .name = __stringify(_name) }, \
194 .ktype = _type, \
195 .uevent_ops =_uevent_ops, \
196}
197
198/* The global /sys/kernel/ subsystem for people to chain off of */
199extern struct kset kernel_subsys;
200/* The global /sys/hypervisor/ subsystem */
201extern struct kset 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)
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)
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.kobj.kset = &(_subsys)
247
248extern void subsystem_init(struct kset *);
249extern int __must_check subsystem_register(struct kset *);
250extern void subsystem_unregister(struct kset *);
251
252static inline struct kset *subsys_get(struct kset *s)
253{
254 if (s)
255 return kset_get(s);
256 return NULL;
257}
258
259static inline void subsys_put(struct kset *s)
260{
261 kset_put(s);
262}
263
264struct subsys_attribute {
265 struct attribute attr;
266 ssize_t (*show)(struct kset *, char *);
267 ssize_t (*store)(struct kset *, const char *, size_t);
268};
269
270extern int __must_check subsys_create_file(struct kset *,
271 struct subsys_attribute *);
272
273#if defined(CONFIG_HOTPLUG)
274int kobject_uevent(struct kobject *kobj, enum kobject_action action);
275int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
276 char *envp[]);
277
278int add_uevent_var(char **envp, int num_envp, int *cur_index,
279 char *buffer, int buffer_size, int *cur_len,
280 const char *format, ...)
281 __attribute__((format (printf, 7, 8)));
282#else
283static inline int kobject_uevent(struct kobject *kobj, enum kobject_action action)
284{ return 0; }
285static inline int kobject_uevent_env(struct kobject *kobj,
286 enum kobject_action action,
287 char *envp[])
288{ return 0; }
289
290static inline int add_uevent_var(char **envp, int num_envp, int *cur_index,
291 char *buffer, int buffer_size, int *cur_len,
292 const char *format, ...)
293{ return 0; }
294#endif
295
296#endif /* __KERNEL__ */
297#endif /* _KOBJECT_H_ */