/*
* kobject.h - generic kernel object infrastructure.
*
* Copyright (c) 2002-2003 Patrick Mochel
* Copyright (c) 2002-2003 Open Source Development Labs
*
* This file is released under the GPLv2.
*
*
* Please read Documentation/kobject.txt before using the kobject
* interface, ESPECIALLY the parts about reference counts and object
* destructors.
*/
#ifndef _KOBJECT_H_
#define _KOBJECT_H_
#ifdef __KERNEL__
#include <linux/types.h>
#include <linux/list.h>
#include <linux/sysfs.h>
#include <linux/spinlock.h>
#include <linux/rwsem.h>
#include <linux/kref.h>
#include <linux/kobject_uevent.h>
#include <linux/kernel.h>
#include <asm/atomic.h>
#define KOBJ_NAME_LEN 20
/* counter to tag the hotplug event, read only except for the kobject core */
extern u64 hotplug_seqnum;
struct kobject {
const char * k_name;
char name[KOBJ_NAME_LEN];
struct kref kref;
struct list_head entry;
struct kobject * parent;
struct kset * kset;
struct kobj_type * ktype;
struct dentry * dentry;
};
extern int kobject_set_name(struct kobject *, const char *, ...)
__attribute__((format(printf,2,3)));
static inline const char * kobject_name(const struct kobject * kobj)
{
return kobj->k_name;
}
extern void kobject_init(struct kobject *);
extern void kobject_cleanup(struct kobject *);
extern int kobject_add(struct kobject *);
extern void kobject_del(struct kobject *);
extern int kobject_rename(struct kobject *, const char *new_name);
extern int kobject_register(struct kobject *);
extern void kobject_unregister(struct kobject *);
extern struct kobject * kobject_get(struct kobject *);
extern void kobject_put(struct kobject *);
extern char * kobject_get_path(struct kobject *, int);
struct kobj_type {
void (*release)(struct kobject *);
struct sysfs_ops * sysfs_ops;
struct attribute ** default_attrs;
};
/**
* kset - a set of kobjects of a specific type, belonging
* to a specific subsystem.
*
* All kobjects of a kset should be embedded in an identical
* type. This type may have a descriptor, which the kset points
* to. This allows there to exist sets of objects of the same
* type in different subsystems.
*
* A subsystem does not have to be a list of only one type
* of object; multiple ksets can belong to one subsystem. All
* ksets of a subsystem share the subsystem's lock.
*
* Each kset can support hotplugging; if it does, it will be given
* the opportunity to filter out specific kobjects from being
* reported, as well as to add its own "data" elements to the
* environment being passed to the hotplug helper.
*/
struct kset_hotplug_ops {
int (*filter)(struct kset *kset, struct kobject *kobj);
const char *(*name)(struct kset *kset, struct kobject *kobj);
int (*hotplug)(struct kset *kset, struct kobject *kobj, char **envp,
int num_envp, char *buffer, int buffer_size);
};
struct kset {
struct subsystem * subsys;
struct kobj_type * ktype;
struct list_head list;
spinlock_t list_lock;
struct kobject kobj;
struct kset_hotplug_ops * hotplug_ops;
};
extern void kset_init(struct kset * k);
extern int kset_add(struct kset * k);
extern int kset_register(struct kset * k);
extern void kset_unregister(struct kset * k);
static inline struct kset * to_kset(struct kobject * kobj)
{
return kobj ? container_of(kobj,struct kset,kobj) : NULL;
}
static inline struct kset * kset_get(struct kset * k)
{
return k ? to_kset(kobject_get(&k->kobj)) : NULL;
}
static inline void kset_put(struct kset * k)
{
kobject_put(&k->kobj);
}
static inline struct kobj_type * get_ktype(struct kobject * k)
{
if (k->kset && k->kset->ktype)
return k->kset->ktype;
else
return k->ktype;
}
extern struct kobject * kset_find_obj(struct kset *, const char *);
/**
* Use this when initializing an embedded kset with no other
* fields to initialize.
*/
#define set_kset_name(str) .kset = { .kobj = { .name = str } }
struct subsystem {
struct kset kset;
struct rw_semaphore rwsem;
};
#define decl_subsys(_name,_type,_hotplug_ops) \
struct subsystem _name##_subsys = { \
.kset = { \
.kobj = { .name = __stringify(_name) }, \
.ktype = _type, \
.hotplug_ops =_hotplug_ops, \
} \
}
#define decl_subsys_name(_varname,_name,_type,_hotplug_ops) \
struct subsystem _varname##_subsys = { \
.kset = { \
.kobj = { .name = __stringify(_name) }, \
.ktype = _type, \
.hotplug_ops =_hotplug_ops, \
} \
}
/* The global /sys/kernel/ subsystem for people to chain off of */
extern struct subsystem kernel_subsys;
/**
* Helpers for setting the kset of registered objects.
* Often, a registered object belongs to a kset embedded in a
* subsystem. These do no magic, just make the resulting code
* easier to follow.
*/
/**
* kobj_set_kset_s(obj,subsys) - set kset for embedded kobject.
* @obj: ptr to some object type.
* @subsys: a subsystem object (not a ptr).
*
* Can be used for any object type with an embedded ->kobj.
*/
#define kobj_set_kset_s(obj,subsys) \
(obj)->kobj.kset = &(subsys).kset
/**
* kset_set_kset_s(obj,subsys) - set kset for embedded kset.
* @obj: ptr to some object type.
* @subsys: a subsystem object (not a ptr).
*
* Can be used for any object type with an embedded ->kset.
* Sets the kset of @obj's embedded kobject (via its embedded
* kset) to @subsys.kset. This makes @obj a member of that
* kset.
*/
#define kset_set_kset_s(obj,subsys) \
(obj)->kset.kobj.kset = &(subsys).kset
/**
* subsys_set_kset(obj,subsys) - set kset for subsystem
* @obj: ptr to some object type.
* @subsys: a subsystem object (not a ptr).
*
* Can be used for any object type with an embedded ->subsys.
* Sets the kset of @obj's kobject to @subsys.kset. This makes
* the object a member of that kset.
*/
#define subsys_set_kset(obj,_subsys) \
(obj)->subsys.kset.kobj.kset = &(_subsys).kset
extern void subsystem_init(struct subsystem *);
extern int subsystem_register(struct subsystem *);
extern void subsystem_unregister(struct subsystem *);
static inline struct subsystem * subsys_get(struct subsystem * s)
{
return s ? container_of(kset_get(&s->kset),struct subsystem,kset) : NULL;
}
static inline void subsys_put(struct subsystem * s)
{
kset_put(&s->kset);
}
struct subsys_attribute {
struct attribute attr;
ssize_t (*show)(struct subsystem *, char *);
ssize_t (*store)(struct subsystem *, const char *, size_t);
};
extern int subsys_create_file(struct subsystem * , struct subsys_attribute *);
extern void subsys_remove_file(struct subsystem * , struct subsys_attribute *);
#ifdef CONFIG_HOTPLUG
void kobject_hotplug(struct kobject *kobj, enum kobject_action action);
int add_hotplug_env_var(char **envp, int num_envp, int *cur_index,
char *buffer, int buffer_size, int *cur_len,
const char *format, ...)
__attribute__((format (printf, 7, 8)));
#else
static inline void kobject_hotplug(struct kobject *kobj, enum kobject_action action) { }
static inline int add_hotplug_env_var(char **envp, int num_envp, int *cur_index,
char *buffer, int buffer_size, int *cur_len,
const char *format, ...)
{ return 0; }
#endif
#endif /* __KERNEL__ */
#endif /* _KOBJECT_H_ */
