2 * kobject.h - generic kernel object infrastructure.
4 * Copyright (c) 2002-2003 Patrick Mochel
5 * Copyright (c) 2002-2003 Open Source Development Labs
7 * This file is released under the GPLv2.
10 * Please read Documentation/kobject.txt before using the kobject
11 * interface, ESPECIALLY the parts about reference counts and object
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>
30 #define KOBJ_NAME_LEN 20
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 */
35 /* path to the userspace helper executed on an event */
36 extern char uevent_helper[];
38 /* counter to tag the uevent, read only except for the kobject core */
39 extern u64 uevent_seqnum;
42 * The actions here must match the index to the string array
43 * in lib/kobject_uevent.c
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.
64 struct list_head entry;
65 struct kobject * parent;
67 struct kobj_type * ktype;
68 struct sysfs_dirent * sd;
69 wait_queue_head_t poll;
72 extern int kobject_set_name(struct kobject *, const char *, ...)
73 __attribute__((format(printf,2,3)));
75 static inline const char * kobject_name(const struct kobject * kobj)
80 extern void kobject_init(struct kobject *);
81 extern void kobject_cleanup(struct kobject *);
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
123 * to a specific subsystem.
125 * All kobjects of a kset should be embedded in an identical
126 * type. This type may have a descriptor, which the kset points
127 * to. This allows there to exist sets of objects of the same
128 * type in different subsystems.
130 * A subsystem does not have to be a list of only one type
131 * of object; multiple ksets can belong to one subsystem. All
132 * ksets of a subsystem share the subsystem's lock.
134 * Each kset can support specific event variables; it can
135 * supress the event generation or add subsystem specific
136 * variables carried with the event.
139 struct kobj_type * ktype;
140 struct list_head list;
141 spinlock_t list_lock;
143 struct kset_uevent_ops * uevent_ops;
147 extern void kset_init(struct kset * k);
148 extern int __must_check kset_add(struct kset * k);
149 extern int __must_check kset_register(struct kset * k);
150 extern void kset_unregister(struct kset * k);
152 static inline struct kset * to_kset(struct kobject * kobj)
154 return kobj ? container_of(kobj,struct kset,kobj) : NULL;
157 static inline struct kset * kset_get(struct kset * k)
159 return k ? to_kset(kobject_get(&k->kobj)) : NULL;
162 static inline void kset_put(struct kset * k)
164 kobject_put(&k->kobj);
167 static inline struct kobj_type * get_ktype(struct kobject * k)
169 if (k->kset && k->kset->ktype)
170 return k->kset->ktype;
175 extern struct kobject * kset_find_obj(struct kset *, const char *);
179 * Use this when initializing an embedded kset with no other
180 * fields to initialize.
182 #define set_kset_name(str) .kset = { .kobj = { .k_name = str } }
185 #define decl_subsys(_name,_type,_uevent_ops) \
186 struct kset _name##_subsys = { \
187 .kobj = { .k_name = __stringify(_name) }, \
189 .uevent_ops =_uevent_ops, \
191 #define decl_subsys_name(_varname,_name,_type,_uevent_ops) \
192 struct kset _varname##_subsys = { \
193 .kobj = { .k_name = __stringify(_name) }, \
195 .uevent_ops =_uevent_ops, \
198 /* The global /sys/kernel/ subsystem for people to chain off of */
199 extern struct kset kernel_subsys;
200 /* The global /sys/hypervisor/ subsystem */
201 extern struct kset hypervisor_subsys;
204 * Helpers for setting the kset of registered objects.
205 * Often, a registered object belongs to a kset embedded in a
206 * subsystem. These do no magic, just make the resulting code
211 * kobj_set_kset_s(obj,subsys) - set kset for embedded kobject.
212 * @obj: ptr to some object type.
213 * @subsys: a subsystem object (not a ptr).
215 * Can be used for any object type with an embedded ->kobj.
218 #define kobj_set_kset_s(obj,subsys) \
219 (obj)->kobj.kset = &(subsys)
221 extern void subsystem_init(struct kset *);
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_ */