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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include <linux/kernel.h>
NeilBrown4508a7a2006-03-20 17:53:53 +110027#include <linux/wait.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070028#include <asm/atomic.h>
29
Kay Sievers312c0042005-11-16 09:00:00 +010030#define KOBJ_NAME_LEN 20
31#define UEVENT_HELPER_PATH_LEN 256
Kay Sievers0296b222005-11-11 05:33:52 +010032
33/* path to the userspace helper executed on an event */
Kay Sievers312c0042005-11-16 09:00:00 +010034extern char uevent_helper[];
Kay Sievers0296b222005-11-11 05:33:52 +010035
Kay Sievers312c0042005-11-16 09:00:00 +010036/* counter to tag the uevent, read only except for the kobject core */
37extern u64 uevent_seqnum;
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
Kay Sievers0296b222005-11-11 05:33:52 +010039/* the actions here must match the proper string in lib/kobject_uevent.c */
40typedef int __bitwise kobject_action_t;
41enum kobject_action {
Kay Sievers5f123fb2005-11-11 14:43:07 +010042 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 */
Greg Kroah-Hartmanfa675762006-02-22 09:39:02 -080045 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 */
Kay Sievers0296b222005-11-11 05:33:52 +010049};
50
Linus Torvalds1da177e2005-04-16 15:20:36 -070051struct kobject {
Dmitry Torokhovf3b4f3c2005-04-26 02:32:00 -050052 const char * k_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -070053 char name[KOBJ_NAME_LEN];
54 struct kref kref;
55 struct list_head entry;
56 struct kobject * parent;
57 struct kset * kset;
58 struct kobj_type * ktype;
59 struct dentry * dentry;
NeilBrown4508a7a2006-03-20 17:53:53 +110060 wait_queue_head_t poll;
Linus Torvalds1da177e2005-04-16 15:20:36 -070061};
62
63extern int kobject_set_name(struct kobject *, const char *, ...)
64 __attribute__((format(printf,2,3)));
65
Dmitry Torokhovf3b4f3c2005-04-26 02:32:00 -050066static inline const char * kobject_name(const struct kobject * kobj)
Linus Torvalds1da177e2005-04-16 15:20:36 -070067{
68 return kobj->k_name;
69}
70
71extern void kobject_init(struct kobject *);
72extern void kobject_cleanup(struct kobject *);
73
74extern int kobject_add(struct kobject *);
75extern void kobject_del(struct kobject *);
76
Dmitry Torokhovf3b4f3c2005-04-26 02:32:00 -050077extern int kobject_rename(struct kobject *, const char *new_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -070078
79extern int kobject_register(struct kobject *);
80extern void kobject_unregister(struct kobject *);
81
82extern struct kobject * kobject_get(struct kobject *);
83extern void kobject_put(struct kobject *);
84
Jun'ichi Nomura74231722006-03-13 17:14:25 -050085extern struct kobject *kobject_add_dir(struct kobject *, const char *);
86
Al Virofd4f2df2005-10-21 03:18:50 -040087extern char * kobject_get_path(struct kobject *, gfp_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -070088
89struct kobj_type {
90 void (*release)(struct kobject *);
91 struct sysfs_ops * sysfs_ops;
92 struct attribute ** default_attrs;
93};
94
95
96/**
97 * kset - a set of kobjects of a specific type, belonging
98 * to a specific subsystem.
99 *
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.
104 *
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.
108 *
Kay Sievers312c0042005-11-16 09:00:00 +0100109 * Each kset can support specific event variables; it can
110 * supress the event generation or add subsystem specific
111 * variables carried with the event.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 */
Kay Sievers312c0042005-11-16 09:00:00 +0100113struct kset_uevent_ops {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114 int (*filter)(struct kset *kset, struct kobject *kobj);
Dmitry Torokhov419cab32005-04-26 02:32:54 -0500115 const char *(*name)(struct kset *kset, struct kobject *kobj);
Kay Sievers312c0042005-11-16 09:00:00 +0100116 int (*uevent)(struct kset *kset, struct kobject *kobj, char **envp,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117 int num_envp, char *buffer, int buffer_size);
118};
119
120struct kset {
121 struct subsystem * subsys;
122 struct kobj_type * ktype;
123 struct list_head list;
124 spinlock_t list_lock;
125 struct kobject kobj;
Kay Sievers312c0042005-11-16 09:00:00 +0100126 struct kset_uevent_ops * uevent_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127};
128
129
130extern void kset_init(struct kset * k);
131extern int kset_add(struct kset * k);
132extern int kset_register(struct kset * k);
133extern void kset_unregister(struct kset * k);
134
135static inline struct kset * to_kset(struct kobject * kobj)
136{
137 return kobj ? container_of(kobj,struct kset,kobj) : NULL;
138}
139
140static inline struct kset * kset_get(struct kset * k)
141{
142 return k ? to_kset(kobject_get(&k->kobj)) : NULL;
143}
144
145static inline void kset_put(struct kset * k)
146{
147 kobject_put(&k->kobj);
148}
149
150static inline struct kobj_type * get_ktype(struct kobject * k)
151{
152 if (k->kset && k->kset->ktype)
153 return k->kset->ktype;
154 else
155 return k->ktype;
156}
157
158extern struct kobject * kset_find_obj(struct kset *, const char *);
159
160
161/**
162 * Use this when initializing an embedded kset with no other
163 * fields to initialize.
164 */
165#define set_kset_name(str) .kset = { .kobj = { .name = str } }
166
167
168
169struct subsystem {
170 struct kset kset;
171 struct rw_semaphore rwsem;
172};
173
Kay Sievers312c0042005-11-16 09:00:00 +0100174#define decl_subsys(_name,_type,_uevent_ops) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175struct subsystem _name##_subsys = { \
176 .kset = { \
177 .kobj = { .name = __stringify(_name) }, \
178 .ktype = _type, \
Kay Sievers312c0042005-11-16 09:00:00 +0100179 .uevent_ops =_uevent_ops, \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180 } \
181}
Kay Sievers312c0042005-11-16 09:00:00 +0100182#define decl_subsys_name(_varname,_name,_type,_uevent_ops) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183struct subsystem _varname##_subsys = { \
184 .kset = { \
185 .kobj = { .name = __stringify(_name) }, \
186 .ktype = _type, \
Kay Sievers312c0042005-11-16 09:00:00 +0100187 .uevent_ops =_uevent_ops, \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188 } \
189}
190
191/* The global /sys/kernel/ subsystem for people to chain off of */
192extern struct subsystem kernel_subsys;
193
194/**
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
198 * easier to follow.
199 */
200
201/**
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).
205 *
206 * Can be used for any object type with an embedded ->kobj.
207 */
208
209#define kobj_set_kset_s(obj,subsys) \
210 (obj)->kobj.kset = &(subsys).kset
211
212/**
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).
216 *
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
220 * kset.
221 */
222
223#define kset_set_kset_s(obj,subsys) \
224 (obj)->kset.kobj.kset = &(subsys).kset
225
226/**
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).
230 *
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.
234 */
235
236#define subsys_set_kset(obj,_subsys) \
237 (obj)->subsys.kset.kobj.kset = &(_subsys).kset
238
239extern void subsystem_init(struct subsystem *);
240extern int subsystem_register(struct subsystem *);
241extern void subsystem_unregister(struct subsystem *);
242
243static inline struct subsystem * subsys_get(struct subsystem * s)
244{
245 return s ? container_of(kset_get(&s->kset),struct subsystem,kset) : NULL;
246}
247
248static inline void subsys_put(struct subsystem * s)
249{
250 kset_put(&s->kset);
251}
252
253struct subsys_attribute {
254 struct attribute attr;
255 ssize_t (*show)(struct subsystem *, char *);
256 ssize_t (*store)(struct subsystem *, const char *, size_t);
257};
258
259extern int subsys_create_file(struct subsystem * , struct subsys_attribute *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260
Kay Sievers4d17ffd2006-04-25 15:37:26 +0200261#if defined(CONFIG_HOTPLUG)
Kay Sievers312c0042005-11-16 09:00:00 +0100262void kobject_uevent(struct kobject *kobj, enum kobject_action action);
Kay Sievers0296b222005-11-11 05:33:52 +0100263
Kay Sievers312c0042005-11-16 09:00:00 +0100264int add_uevent_var(char **envp, int num_envp, int *cur_index,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265 char *buffer, int buffer_size, int *cur_len,
266 const char *format, ...)
267 __attribute__((format (printf, 7, 8)));
268#else
Kay Sievers312c0042005-11-16 09:00:00 +0100269static inline void kobject_uevent(struct kobject *kobj, enum kobject_action action) { }
Kay Sievers5f123fb2005-11-11 14:43:07 +0100270
Kay Sievers312c0042005-11-16 09:00:00 +0100271static inline int add_uevent_var(char **envp, int num_envp, int *cur_index,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 char *buffer, int buffer_size, int *cur_len,
273 const char *format, ...)
274{ return 0; }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275#endif
276
277#endif /* __KERNEL__ */
278#endif /* _KOBJECT_H_ */