2 * kobject.h - generic kernel object infrastructure.
4 * Copyright (c) 2002-2003 Patrick Mochel
5 * Copyright (c) 2002-2003 Open Source Development Labs
6 * Copyright (c) 2006-2007 Greg Kroah-Hartman <greg@kroah.com>
7 * Copyright (c) 2006-2007 Novell Inc.
9 * This file is released under the GPLv2.
12 * Please read Documentation/kobject.txt before using the kobject
13 * interface, ESPECIALLY the parts about reference counts and object
22 #include <linux/types.h>
23 #include <linux/list.h>
24 #include <linux/sysfs.h>
25 #include <linux/compiler.h>
26 #include <linux/spinlock.h>
27 #include <linux/kref.h>
28 #include <linux/kernel.h>
29 #include <linux/wait.h>
30 #include <asm/atomic.h>
32 #define KOBJ_NAME_LEN 20
33 #define UEVENT_HELPER_PATH_LEN 256
34 #define UEVENT_NUM_ENVP 32 /* number of env pointers */
35 #define UEVENT_BUFFER_SIZE 2048 /* buffer for the variables */
37 /* path to the userspace helper executed on an event */
38 extern char uevent_helper[];
40 /* counter to tag the uevent, read only except for the kobject core */
41 extern u64 uevent_seqnum;
44 * The actions here must match the index to the string array
45 * in lib/kobject_uevent.c
47 * Do not add new actions here without checking with the driver-core
48 * maintainers. Action strings are not meant to express subsystem
49 * or device specific properties. In most cases you want to send a
50 * kobject_uevent_env(kobj, KOBJ_CHANGE, env) with additional event
51 * specific variables added to the event environment.
66 struct list_head entry;
67 struct kobject * parent;
69 struct kobj_type * ktype;
70 struct sysfs_dirent * sd;
73 extern int kobject_set_name(struct kobject *, const char *, ...)
74 __attribute__((format(printf,2,3)));
76 static inline const char * kobject_name(const struct kobject * kobj)
81 extern void kobject_init(struct kobject *);
82 extern void kobject_init_ng(struct kobject *kobj, struct kobj_type *ktype);
83 extern int __must_check kobject_add(struct kobject *);
84 extern void kobject_del(struct kobject *);
86 extern int __must_check kobject_rename(struct kobject *, const char *new_name);
87 extern int __must_check kobject_move(struct kobject *, struct kobject *);
89 extern int __must_check kobject_register(struct kobject *);
90 extern void kobject_unregister(struct kobject *);
92 extern struct kobject * kobject_get(struct kobject *);
93 extern void kobject_put(struct kobject *);
95 extern struct kobject *kobject_kset_add_dir(struct kset *kset,
96 struct kobject *, const char *);
97 extern struct kobject *kobject_add_dir(struct kobject *, const char *);
99 extern char * kobject_get_path(struct kobject *, gfp_t);
102 void (*release)(struct kobject *);
103 struct sysfs_ops * sysfs_ops;
104 struct attribute ** default_attrs;
107 struct kobj_uevent_env {
108 char *envp[UEVENT_NUM_ENVP];
110 char buf[UEVENT_BUFFER_SIZE];
114 struct 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,
118 struct kobj_uevent_env *env);
122 * struct kset - a set of kobjects of a specific type, belonging to a specific subsystem.
124 * A kset defines a group of kobjects. They can be individually
125 * different "types" but overall these kobjects all want to be grouped
126 * together and operated on in the same manner. ksets are used to
127 * define the attribute callbacks and other common events that happen to
130 * @ktype: the struct kobj_type for this specific kset
131 * @list: the list of all kobjects for this kset
132 * @list_lock: a lock for iterating over the kobjects
133 * @kobj: the embedded kobject for this kset (recursion, isn't it fun...)
134 * @uevent_ops: the set of uevent operations for this kset. These are
135 * called whenever a kobject has something happen to it so that the kset
136 * can add new environment variables, or filter out the uevents if so
140 struct kobj_type *ktype;
141 struct list_head list;
142 spinlock_t list_lock;
144 struct kset_uevent_ops *uevent_ops;
148 extern void kset_init(struct kset * k);
149 extern int __must_check kset_add(struct kset * k);
150 extern int __must_check kset_register(struct kset * k);
151 extern void kset_unregister(struct kset * k);
153 static inline struct kset * to_kset(struct kobject * kobj)
155 return kobj ? container_of(kobj,struct kset,kobj) : NULL;
158 static inline struct kset * kset_get(struct kset * k)
160 return k ? to_kset(kobject_get(&k->kobj)) : NULL;
163 static inline void kset_put(struct kset * k)
165 kobject_put(&k->kobj);
168 static inline struct kobj_type * get_ktype(struct kobject * k)
170 if (k->kset && k->kset->ktype)
171 return k->kset->ktype;
176 extern struct kobject * kset_find_obj(struct kset *, const char *);
180 * Use this when initializing an embedded kset with no other
181 * fields to initialize.
183 #define set_kset_name(str) .kset = { .kobj = { .k_name = str } }
186 #define decl_subsys(_name,_type,_uevent_ops) \
187 struct kset _name##_subsys = { \
188 .kobj = { .k_name = __stringify(_name) }, \
190 .uevent_ops =_uevent_ops, \
192 #define decl_subsys_name(_varname,_name,_type,_uevent_ops) \
193 struct kset _varname##_subsys = { \
194 .kobj = { .k_name = __stringify(_name) }, \
196 .uevent_ops =_uevent_ops, \
199 /* The global /sys/kernel/ subsystem for people to chain off of */
200 extern struct kset kernel_subsys;
201 /* The global /sys/hypervisor/ subsystem */
202 extern struct kset hypervisor_subsys;
205 * Helpers for setting the kset of registered objects.
206 * Often, a registered object belongs to a kset embedded in a
207 * subsystem. These do no magic, just make the resulting code
212 * kobj_set_kset_s(obj,subsys) - set kset for embedded kobject.
213 * @obj: ptr to some object type.
214 * @subsys: a subsystem object (not a ptr).
216 * Can be used for any object type with an embedded ->kobj.
219 #define kobj_set_kset_s(obj,subsys) \
220 (obj)->kobj.kset = &(subsys)
222 extern int __must_check subsystem_register(struct kset *);
223 extern void subsystem_unregister(struct kset *);
225 struct subsys_attribute {
226 struct attribute attr;
227 ssize_t (*show)(struct kset *, char *);
228 ssize_t (*store)(struct kset *, const char *, size_t);
231 extern int __must_check subsys_create_file(struct kset *,
232 struct subsys_attribute *);
234 #if defined(CONFIG_HOTPLUG)
235 int kobject_uevent(struct kobject *kobj, enum kobject_action action);
236 int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
239 int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...)
240 __attribute__((format (printf, 2, 3)));
242 int kobject_action_type(const char *buf, size_t count,
243 enum kobject_action *type);
245 static inline int kobject_uevent(struct kobject *kobj, enum kobject_action action)
247 static inline int kobject_uevent_env(struct kobject *kobj,
248 enum kobject_action action,
252 static inline int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...)
255 static inline int kobject_action_type(const char *buf, size_t count,
256 enum kobject_action *type)
260 #endif /* __KERNEL__ */
261 #endif /* _KOBJECT_H_ */