Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
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
59struct kobject {
60 const char * k_name;
61 char name[KOBJ_NAME_LEN];
62 struct kref kref;
63 struct list_head entry;
64 struct kobject * parent;
65 struct kset * kset;
66 struct kobj_type * ktype;
67 struct sysfs_dirent * sd;
68 wait_queue_head_t poll;
69};
70
71extern int kobject_set_name(struct kobject *, const char *, ...)
72 __attribute__((format(printf,2,3)));
73
74static inline const char * kobject_name(const struct kobject * kobj)
75{
76 return kobj->k_name;
77}
78
79extern void kobject_init(struct kobject *);
80extern void kobject_cleanup(struct kobject *);
81
82extern int __must_check kobject_add(struct kobject *);
83extern int __must_check kobject_shadow_add(struct kobject *kobj,
84 struct sysfs_dirent *shadow_parent);
85extern void kobject_del(struct kobject *);
86
87extern int __must_check kobject_rename(struct kobject *, const char *new_name);
88extern int __must_check kobject_shadow_rename(struct kobject *kobj,
89 struct sysfs_dirent *new_parent,
90 const char *new_name);
91extern int __must_check kobject_move(struct kobject *, struct kobject *);
92
93extern int __must_check kobject_register(struct kobject *);
94extern void kobject_unregister(struct kobject *);
95
96extern struct kobject * kobject_get(struct kobject *);
97extern void kobject_put(struct kobject *);
98
99extern struct kobject *kobject_kset_add_dir(struct kset *kset,
100 struct kobject *, const char *);
101extern struct kobject *kobject_add_dir(struct kobject *, const char *);
102
103extern char * kobject_get_path(struct kobject *, gfp_t);
104
105struct kobj_type {
106 void (*release)(struct kobject *);
107 struct sysfs_ops * sysfs_ops;
108 struct attribute ** default_attrs;
109};
110
111
112/**
113 * kset - a set of kobjects of a specific type, belonging
114 * to a specific subsystem.
115 *
116 * All kobjects of a kset should be embedded in an identical
117 * type. This type may have a descriptor, which the kset points
118 * to. This allows there to exist sets of objects of the same
119 * type in different subsystems.
120 *
121 * A subsystem does not have to be a list of only one type
122 * of object; multiple ksets can belong to one subsystem. All
123 * ksets of a subsystem share the subsystem's lock.
124 *
125 * Each kset can support specific event variables; it can
126 * supress the event generation or add subsystem specific
127 * variables carried with the event.
128 */
129struct kset_uevent_ops {
130 int (*filter)(struct kset *kset, struct kobject *kobj);
131 const char *(*name)(struct kset *kset, struct kobject *kobj);
132 int (*uevent)(struct kset *kset, struct kobject *kobj, char **envp,
133 int num_envp, char *buffer, int buffer_size);
134};
135
136struct kset {
137 struct kobj_type * ktype;
138 struct list_head list;
139 spinlock_t list_lock;
140 struct kobject kobj;
141 struct kset_uevent_ops * uevent_ops;
142};
143
144
145extern void kset_init(struct kset * k);
146extern int __must_check kset_add(struct kset * k);
147extern int __must_check kset_register(struct kset * k);
148extern void kset_unregister(struct kset * k);
149
150static inline struct kset * to_kset(struct kobject * kobj)
151{
152 return kobj ? container_of(kobj,struct kset,kobj) : NULL;
153}
154
155static inline struct kset * kset_get(struct kset * k)
156{
157 return k ? to_kset(kobject_get(&k->kobj)) : NULL;
158}
159
160static inline void kset_put(struct kset * k)
161{
162 kobject_put(&k->kobj);
163}
164
165static inline struct kobj_type * get_ktype(struct kobject * k)
166{
167 if (k->kset && k->kset->ktype)
168 return k->kset->ktype;
169 else
170 return k->ktype;
171}
172
173extern struct kobject * kset_find_obj(struct kset *, const char *);
174
175
176/**
177 * Use this when initializing an embedded kset with no other
178 * fields to initialize.
179 */
180#define set_kset_name(str) .kset = { .kobj = { .name = str } }
181
182
183#define decl_subsys(_name,_type,_uevent_ops) \
184struct kset _name##_subsys = { \
185 .kobj = { .name = __stringify(_name) }, \
186 .ktype = _type, \
187 .uevent_ops =_uevent_ops, \
188}
189#define decl_subsys_name(_varname,_name,_type,_uevent_ops) \
190struct kset _varname##_subsys = { \
191 .kobj = { .name = __stringify(_name) }, \
192 .ktype = _type, \
193 .uevent_ops =_uevent_ops, \
194}
195
196/* The global /sys/kernel/ subsystem for people to chain off of */
197extern struct kset kernel_subsys;
198/* The global /sys/hypervisor/ subsystem */
199extern struct kset hypervisor_subsys;
200
201/**
202 * Helpers for setting the kset of registered objects.
203 * Often, a registered object belongs to a kset embedded in a
204 * subsystem. These do no magic, just make the resulting code
205 * easier to follow.
206 */
207
208/**
209 * kobj_set_kset_s(obj,subsys) - set kset for embedded kobject.
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 ->kobj.
214 */
215
216#define kobj_set_kset_s(obj,subsys) \
217 (obj)->kobj.kset = &(subsys)
218
219/**
220 * kset_set_kset_s(obj,subsys) - set kset for embedded kset.
221 * @obj: ptr to some object type.
222 * @subsys: a subsystem object (not a ptr).
223 *
224 * Can be used for any object type with an embedded ->kset.
225 * Sets the kset of @obj's embedded kobject (via its embedded
226 * kset) to @subsys.kset. This makes @obj a member of that
227 * kset.
228 */
229
230#define kset_set_kset_s(obj,subsys) \
231 (obj)->kset.kobj.kset = &(subsys)
232
233/**
234 * subsys_set_kset(obj,subsys) - set kset for subsystem
235 * @obj: ptr to some object type.
236 * @subsys: a subsystem object (not a ptr).
237 *
238 * Can be used for any object type with an embedded ->subsys.
239 * Sets the kset of @obj's kobject to @subsys.kset. This makes
240 * the object a member of that kset.
241 */
242
243#define subsys_set_kset(obj,_subsys) \
244 (obj)->subsys.kobj.kset = &(_subsys)
245
246extern void subsystem_init(struct kset *);
247extern int __must_check subsystem_register(struct kset *);
248extern void subsystem_unregister(struct kset *);
249
250static inline struct kset *subsys_get(struct kset *s)
251{
252 if (s)
253 return kset_get(s);
254 return NULL;
255}
256
257static inline void subsys_put(struct kset *s)
258{
259 kset_put(s);
260}
261
262struct subsys_attribute {
263 struct attribute attr;
264 ssize_t (*show)(struct kset *, char *);
265 ssize_t (*store)(struct kset *, const char *, size_t);
266};
267
268extern int __must_check subsys_create_file(struct kset *,
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_ */