projects/linux·blob v3.13 · refs

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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 * Copyright (c) 2006-2008 Greg Kroah-Hartman <[email protected]>
7 * Copyright (c) 2006-2008 Novell Inc.
8 *
9 * This file is released under the GPLv2.
10 *
11 * Please read Documentation/kobject.txt before using the kobject
12 * interface, ESPECIALLY the parts about reference counts and object
13 * destructors.
14 */
15
16#ifndef _KOBJECT_H_
17#define _KOBJECT_H_
18
19#include <linux/types.h>
20#include <linux/list.h>
21#include <linux/sysfs.h>
22#include <linux/compiler.h>
23#include <linux/spinlock.h>
24#include <linux/kref.h>
25#include <linux/kobject_ns.h>
26#include <linux/kernel.h>
27#include <linux/wait.h>
28#include <linux/atomic.h>
29#include <linux/workqueue.h>
30
31#define UEVENT_HELPER_PATH_LEN 256
32#define UEVENT_NUM_ENVP 32 /* number of env pointers */
33#define UEVENT_BUFFER_SIZE 2048 /* buffer for the variables */
34
35/* path to the userspace helper executed on an event */
36extern char uevent_helper[];
37
38/* counter to tag the uevent, read only except for the kobject core */
39extern u64 uevent_seqnum;
40
41/*
42 * The actions here must match the index to the string array
43 * in lib/kobject_uevent.c
44 *
45 * Do not add new actions here without checking with the driver-core
46 * maintainers. Action strings are not meant to express subsystem
47 * or device specific properties. In most cases you want to send a
48 * kobject_uevent_env(kobj, KOBJ_CHANGE, env) with additional event
49 * specific variables added to the event environment.
50 */
51enum kobject_action {
52 KOBJ_ADD,
53 KOBJ_REMOVE,
54 KOBJ_CHANGE,
55 KOBJ_MOVE,
56 KOBJ_ONLINE,
57 KOBJ_OFFLINE,
58 KOBJ_MAX
59};
60
61struct kobject {
62 const char *name;
63 struct list_head entry;
64 struct kobject *parent;
65 struct kset *kset;
66 struct kobj_type *ktype;
67 struct sysfs_dirent *sd;
68 struct kref kref;
69#ifdef CONFIG_DEBUG_KOBJECT_RELEASE
70 struct delayed_work release;
71#endif
72 unsigned int state_initialized:1;
73 unsigned int state_in_sysfs:1;
74 unsigned int state_add_uevent_sent:1;
75 unsigned int state_remove_uevent_sent:1;
76 unsigned int uevent_suppress:1;
77};
78
79extern __printf(2, 3)
80int kobject_set_name(struct kobject *kobj, const char *name, ...);
81extern int kobject_set_name_vargs(struct kobject *kobj, const char *fmt,
82 va_list vargs);
83
84static inline const char *kobject_name(const struct kobject *kobj)
85{
86 return kobj->name;
87}
88
89extern void kobject_init(struct kobject *kobj, struct kobj_type *ktype);
90extern __printf(3, 4) __must_check
91int kobject_add(struct kobject *kobj, struct kobject *parent,
92 const char *fmt, ...);
93extern __printf(4, 5) __must_check
94int kobject_init_and_add(struct kobject *kobj,
95 struct kobj_type *ktype, struct kobject *parent,
96 const char *fmt, ...);
97
98extern void kobject_del(struct kobject *kobj);
99
100extern struct kobject * __must_check kobject_create(void);
101extern struct kobject * __must_check kobject_create_and_add(const char *name,
102 struct kobject *parent);
103
104extern int __must_check kobject_rename(struct kobject *, const char *new_name);
105extern int __must_check kobject_move(struct kobject *, struct kobject *);
106
107extern struct kobject *kobject_get(struct kobject *kobj);
108extern void kobject_put(struct kobject *kobj);
109
110extern const void *kobject_namespace(struct kobject *kobj);
111extern char *kobject_get_path(struct kobject *kobj, gfp_t flag);
112
113struct kobj_type {
114 void (*release)(struct kobject *kobj);
115 const struct sysfs_ops *sysfs_ops;
116 struct attribute **default_attrs;
117 const struct kobj_ns_type_operations *(*child_ns_type)(struct kobject *kobj);
118 const void *(*namespace)(struct kobject *kobj);
119};
120
121struct kobj_uevent_env {
122 char *envp[UEVENT_NUM_ENVP];
123 int envp_idx;
124 char buf[UEVENT_BUFFER_SIZE];
125 int buflen;
126};
127
128struct kset_uevent_ops {
129 int (* const filter)(struct kset *kset, struct kobject *kobj);
130 const char *(* const name)(struct kset *kset, struct kobject *kobj);
131 int (* const uevent)(struct kset *kset, struct kobject *kobj,
132 struct kobj_uevent_env *env);
133};
134
135struct kobj_attribute {
136 struct attribute attr;
137 ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr,
138 char *buf);
139 ssize_t (*store)(struct kobject *kobj, struct kobj_attribute *attr,
140 const char *buf, size_t count);
141};
142
143extern const struct sysfs_ops kobj_sysfs_ops;
144
145struct sock;
146
147/**
148 * struct kset - a set of kobjects of a specific type, belonging to a specific subsystem.
149 *
150 * A kset defines a group of kobjects. They can be individually
151 * different "types" but overall these kobjects all want to be grouped
152 * together and operated on in the same manner. ksets are used to
153 * define the attribute callbacks and other common events that happen to
154 * a kobject.
155 *
156 * @list: the list of all kobjects for this kset
157 * @list_lock: a lock for iterating over the kobjects
158 * @kobj: the embedded kobject for this kset (recursion, isn't it fun...)
159 * @uevent_ops: the set of uevent operations for this kset. These are
160 * called whenever a kobject has something happen to it so that the kset
161 * can add new environment variables, or filter out the uevents if so
162 * desired.
163 */
164struct kset {
165 struct list_head list;
166 spinlock_t list_lock;
167 struct kobject kobj;
168 const struct kset_uevent_ops *uevent_ops;
169};
170
171extern void kset_init(struct kset *kset);
172extern int __must_check kset_register(struct kset *kset);
173extern void kset_unregister(struct kset *kset);
174extern struct kset * __must_check kset_create_and_add(const char *name,
175 const struct kset_uevent_ops *u,
176 struct kobject *parent_kobj);
177
178static inline struct kset *to_kset(struct kobject *kobj)
179{
180 return kobj ? container_of(kobj, struct kset, kobj) : NULL;
181}
182
183static inline struct kset *kset_get(struct kset *k)
184{
185 return k ? to_kset(kobject_get(&k->kobj)) : NULL;
186}
187
188static inline void kset_put(struct kset *k)
189{
190 kobject_put(&k->kobj);
191}
192
193static inline struct kobj_type *get_ktype(struct kobject *kobj)
194{
195 return kobj->ktype;
196}
197
198extern struct kobject *kset_find_obj(struct kset *, const char *);
199
200/* The global /sys/kernel/ kobject for people to chain off of */
201extern struct kobject *kernel_kobj;
202/* The global /sys/kernel/mm/ kobject for people to chain off of */
203extern struct kobject *mm_kobj;
204/* The global /sys/hypervisor/ kobject for people to chain off of */
205extern struct kobject *hypervisor_kobj;
206/* The global /sys/power/ kobject for people to chain off of */
207extern struct kobject *power_kobj;
208/* The global /sys/firmware/ kobject for people to chain off of */
209extern struct kobject *firmware_kobj;
210
211int kobject_uevent(struct kobject *kobj, enum kobject_action action);
212int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
213 char *envp[]);
214
215__printf(2, 3)
216int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...);
217
218int kobject_action_type(const char *buf, size_t count,
219 enum kobject_action *type);
220
221#endif /* _KOBJECT_H_ */