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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>
Andrew Morton4a7fb632006-08-14 22:43:17 -070023#include <linux/compiler.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <linux/spinlock.h>
25#include <linux/rwsem.h>
26#include <linux/kref.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <linux/kernel.h>
NeilBrown4508a7a2006-03-20 17:53:53 +110028#include <linux/wait.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#include <asm/atomic.h>
30
Kay Sievers312c0042005-11-16 09:00:00 +010031#define KOBJ_NAME_LEN 20
32#define UEVENT_HELPER_PATH_LEN 256
Kay Sievers0296b222005-11-11 05:33:52 +010033
34/* path to the userspace helper executed on an event */
Kay Sievers312c0042005-11-16 09:00:00 +010035extern char uevent_helper[];
Kay Sievers0296b222005-11-11 05:33:52 +010036
Kay Sievers312c0042005-11-16 09:00:00 +010037/* counter to tag the uevent, read only except for the kobject core */
38extern u64 uevent_seqnum;
Linus Torvalds1da177e2005-04-16 15:20:36 -070039
Kay Sievers0296b222005-11-11 05:33:52 +010040/* the actions here must match the proper string in lib/kobject_uevent.c */
41typedef int __bitwise kobject_action_t;
42enum kobject_action {
Kay Sievers5f123fb2005-11-11 14:43:07 +010043 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 */
Greg Kroah-Hartmanfa675762006-02-22 09:39:02 -080046 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 */
Kay Sievers0296b222005-11-11 05:33:52 +010050};
51
Linus Torvalds1da177e2005-04-16 15:20:36 -070052struct kobject {
Dmitry Torokhovf3b4f3c2005-04-26 02:32:00 -050053 const char * k_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -070054 char name[KOBJ_NAME_LEN];
55 struct kref kref;
56 struct list_head entry;
57 struct kobject * parent;
58 struct kset * kset;
59 struct kobj_type * ktype;
60 struct dentry * dentry;
NeilBrown4508a7a2006-03-20 17:53:53 +110061 wait_queue_head_t poll;
Linus Torvalds1da177e2005-04-16 15:20:36 -070062};
63
64extern int kobject_set_name(struct kobject *, const char *, ...)
65 __attribute__((format(printf,2,3)));
66
Dmitry Torokhovf3b4f3c2005-04-26 02:32:00 -050067static inline const char * kobject_name(const struct kobject * kobj)
Linus Torvalds1da177e2005-04-16 15:20:36 -070068{
69 return kobj->k_name;
70}
71
72extern void kobject_init(struct kobject *);
73extern void kobject_cleanup(struct kobject *);
74
Andrew Morton4a7fb632006-08-14 22:43:17 -070075extern int __must_check kobject_add(struct kobject *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070076extern void kobject_del(struct kobject *);
77
Andrew Morton4a7fb632006-08-14 22:43:17 -070078extern int __must_check kobject_rename(struct kobject *, const char *new_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -070079
Andrew Morton4a7fb632006-08-14 22:43:17 -070080extern int __must_check kobject_register(struct kobject *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070081extern void kobject_unregister(struct kobject *);
82
83extern struct kobject * kobject_get(struct kobject *);
84extern void kobject_put(struct kobject *);
85
Jun'ichi Nomura74231722006-03-13 17:14:25 -050086extern struct kobject *kobject_add_dir(struct kobject *, const char *);
87
Al Virofd4f2df2005-10-21 03:18:50 -040088extern char * kobject_get_path(struct kobject *, gfp_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -070089
90struct kobj_type {
91 void (*release)(struct kobject *);
92 struct sysfs_ops * sysfs_ops;
93 struct attribute ** default_attrs;
94};
95
96
97/**
98 * kset - a set of kobjects of a specific type, belonging
99 * to a specific subsystem.
100 *
101 * All kobjects of a kset should be embedded in an identical
102 * type. This type may have a descriptor, which the kset points
103 * to. This allows there to exist sets of objects of the same
104 * type in different subsystems.
105 *
106 * A subsystem does not have to be a list of only one type
107 * of object; multiple ksets can belong to one subsystem. All
108 * ksets of a subsystem share the subsystem's lock.
109 *
Kay Sievers312c0042005-11-16 09:00:00 +0100110 * Each kset can support specific event variables; it can
111 * supress the event generation or add subsystem specific
112 * variables carried with the event.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113 */
Kay Sievers312c0042005-11-16 09:00:00 +0100114struct kset_uevent_ops {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 int (*filter)(struct kset *kset, struct kobject *kobj);
Dmitry Torokhov419cab32005-04-26 02:32:54 -0500116 const char *(*name)(struct kset *kset, struct kobject *kobj);
Kay Sievers312c0042005-11-16 09:00:00 +0100117 int (*uevent)(struct kset *kset, struct kobject *kobj, char **envp,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 int num_envp, char *buffer, int buffer_size);
119};
120
121struct kset {
122 struct subsystem * subsys;
123 struct kobj_type * ktype;
124 struct list_head list;
125 spinlock_t list_lock;
126 struct kobject kobj;
Kay Sievers312c0042005-11-16 09:00:00 +0100127 struct kset_uevent_ops * uevent_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128};
129
130
131extern void kset_init(struct kset * k);
Andrew Morton4a7fb632006-08-14 22:43:17 -0700132extern int __must_check kset_add(struct kset * k);
133extern int __must_check kset_register(struct kset * k);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134extern void kset_unregister(struct kset * k);
135
136static inline struct kset * to_kset(struct kobject * kobj)
137{
138 return kobj ? container_of(kobj,struct kset,kobj) : NULL;
139}
140
141static inline struct kset * kset_get(struct kset * k)
142{
143 return k ? to_kset(kobject_get(&k->kobj)) : NULL;
144}
145
146static inline void kset_put(struct kset * k)
147{
148 kobject_put(&k->kobj);
149}
150
151static inline struct kobj_type * get_ktype(struct kobject * k)
152{
153 if (k->kset && k->kset->ktype)
154 return k->kset->ktype;
155 else
156 return k->ktype;
157}
158
159extern struct kobject * kset_find_obj(struct kset *, const char *);
160
161
162/**
163 * Use this when initializing an embedded kset with no other
164 * fields to initialize.
165 */
166#define set_kset_name(str) .kset = { .kobj = { .name = str } }
167
168
169
170struct subsystem {
171 struct kset kset;
172 struct rw_semaphore rwsem;
173};
174
Kay Sievers312c0042005-11-16 09:00:00 +0100175#define decl_subsys(_name,_type,_uevent_ops) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176struct subsystem _name##_subsys = { \
177 .kset = { \
178 .kobj = { .name = __stringify(_name) }, \
179 .ktype = _type, \
Kay Sievers312c0042005-11-16 09:00:00 +0100180 .uevent_ops =_uevent_ops, \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181 } \
182}
Kay Sievers312c0042005-11-16 09:00:00 +0100183#define decl_subsys_name(_varname,_name,_type,_uevent_ops) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184struct subsystem _varname##_subsys = { \
185 .kset = { \
186 .kobj = { .name = __stringify(_name) }, \
187 .ktype = _type, \
Kay Sievers312c0042005-11-16 09:00:00 +0100188 .uevent_ops =_uevent_ops, \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189 } \
190}
191
192/* The global /sys/kernel/ subsystem for people to chain off of */
193extern struct subsystem kernel_subsys;
Michael Holzheu40394832006-05-09 12:53:49 +0200194/* The global /sys/hypervisor/ subsystem */
195extern struct subsystem hypervisor_subsys;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196
197/**
198 * Helpers for setting the kset of registered objects.
199 * Often, a registered object belongs to a kset embedded in a
200 * subsystem. These do no magic, just make the resulting code
201 * easier to follow.
202 */
203
204/**
205 * kobj_set_kset_s(obj,subsys) - set kset for embedded kobject.
206 * @obj: ptr to some object type.
207 * @subsys: a subsystem object (not a ptr).
208 *
209 * Can be used for any object type with an embedded ->kobj.
210 */
211
212#define kobj_set_kset_s(obj,subsys) \
213 (obj)->kobj.kset = &(subsys).kset
214
215/**
216 * kset_set_kset_s(obj,subsys) - set kset for embedded kset.
217 * @obj: ptr to some object type.
218 * @subsys: a subsystem object (not a ptr).
219 *
220 * Can be used for any object type with an embedded ->kset.
221 * Sets the kset of @obj's embedded kobject (via its embedded
222 * kset) to @subsys.kset. This makes @obj a member of that
223 * kset.
224 */
225
226#define kset_set_kset_s(obj,subsys) \
227 (obj)->kset.kobj.kset = &(subsys).kset
228
229/**
230 * subsys_set_kset(obj,subsys) - set kset for subsystem
231 * @obj: ptr to some object type.
232 * @subsys: a subsystem object (not a ptr).
233 *
234 * Can be used for any object type with an embedded ->subsys.
235 * Sets the kset of @obj's kobject to @subsys.kset. This makes
236 * the object a member of that kset.
237 */
238
239#define subsys_set_kset(obj,_subsys) \
240 (obj)->subsys.kset.kobj.kset = &(_subsys).kset
241
242extern void subsystem_init(struct subsystem *);
Andrew Morton4a7fb632006-08-14 22:43:17 -0700243extern int __must_check subsystem_register(struct subsystem *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244extern void subsystem_unregister(struct subsystem *);
245
246static inline struct subsystem * subsys_get(struct subsystem * s)
247{
248 return s ? container_of(kset_get(&s->kset),struct subsystem,kset) : NULL;
249}
250
251static inline void subsys_put(struct subsystem * s)
252{
253 kset_put(&s->kset);
254}
255
256struct subsys_attribute {
257 struct attribute attr;
258 ssize_t (*show)(struct subsystem *, char *);
259 ssize_t (*store)(struct subsystem *, const char *, size_t);
260};
261
Andrew Morton4a7fb632006-08-14 22:43:17 -0700262extern int __must_check subsys_create_file(struct subsystem * ,
263 struct subsys_attribute *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264
Kay Sievers4d17ffd2006-04-25 15:37:26 +0200265#if defined(CONFIG_HOTPLUG)
Kay Sievers312c0042005-11-16 09:00:00 +0100266void kobject_uevent(struct kobject *kobj, enum kobject_action action);
Kay Sievers0296b222005-11-11 05:33:52 +0100267
Kay Sievers312c0042005-11-16 09:00:00 +0100268int add_uevent_var(char **envp, int num_envp, int *cur_index,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 char *buffer, int buffer_size, int *cur_len,
270 const char *format, ...)
271 __attribute__((format (printf, 7, 8)));
272#else
Kay Sievers312c0042005-11-16 09:00:00 +0100273static inline void kobject_uevent(struct kobject *kobj, enum kobject_action action) { }
Kay Sievers5f123fb2005-11-11 14:43:07 +0100274
Kay Sievers312c0042005-11-16 09:00:00 +0100275static inline int add_uevent_var(char **envp, int num_envp, int *cur_index,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 char *buffer, int buffer_size, int *cur_len,
277 const char *format, ...)
278{ return 0; }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279#endif
280
281#endif /* __KERNEL__ */
282#endif /* _KOBJECT_H_ */