linux-hardened/include/linux/kobject.h
Emese Revfy 52cf25d0ab Driver core: Constify struct sysfs_ops in struct kobj_type
Constify struct sysfs_ops.

This is part of the ops structure constification
effort started by Arjan van de Ven et al.

Benefits of this constification:

 * prevents modification of data that is shared
   (referenced) by many other structure instances
   at runtime

 * detects/prevents accidental (but not intentional)
   modification attempts on archs that enforce
   read-only kernel data at runtime

 * potentially better optimized code as the compiler
   can assume that the const data cannot be changed

 * the compiler/linker move const data into .rodata
   and therefore exclude them from false sharing

Signed-off-by: Emese Revfy <re.emese@gmail.com>
Acked-by: David Teigland <teigland@redhat.com>
Acked-by: Matt Domsch <Matt_Domsch@dell.com>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Acked-by: Hans J. Koch <hjk@linutronix.de>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-07 17:04:49 -08:00

229 lines
6.9 KiB
C

/*
* kobject.h - generic kernel object infrastructure.
*
* Copyright (c) 2002-2003 Patrick Mochel
* Copyright (c) 2002-2003 Open Source Development Labs
* Copyright (c) 2006-2008 Greg Kroah-Hartman <greg@kroah.com>
* Copyright (c) 2006-2008 Novell Inc.
*
* 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_
#include <linux/types.h>
#include <linux/list.h>
#include <linux/sysfs.h>
#include <linux/compiler.h>
#include <linux/spinlock.h>
#include <linux/kref.h>
#include <linux/kernel.h>
#include <linux/wait.h>
#include <asm/atomic.h>
#define UEVENT_HELPER_PATH_LEN 256
#define UEVENT_NUM_ENVP 32 /* number of env pointers */
#define UEVENT_BUFFER_SIZE 2048 /* buffer for the variables */
/* path to the userspace helper executed on an event */
extern char uevent_helper[];
/* counter to tag the uevent, read only except for the kobject core */
extern u64 uevent_seqnum;
/*
* The actions here must match the index to the string array
* in lib/kobject_uevent.c
*
* Do not add new actions here without checking with the driver-core
* maintainers. Action strings are not meant to express subsystem
* or device specific properties. In most cases you want to send a
* kobject_uevent_env(kobj, KOBJ_CHANGE, env) with additional event
* specific variables added to the event environment.
*/
enum kobject_action {
KOBJ_ADD,
KOBJ_REMOVE,
KOBJ_CHANGE,
KOBJ_MOVE,
KOBJ_ONLINE,
KOBJ_OFFLINE,
KOBJ_MAX
};
struct kobject {
const char *name;
struct list_head entry;
struct kobject *parent;
struct kset *kset;
struct kobj_type *ktype;
struct sysfs_dirent *sd;
struct kref kref;
unsigned int state_initialized:1;
unsigned int state_in_sysfs:1;
unsigned int state_add_uevent_sent:1;
unsigned int state_remove_uevent_sent:1;
unsigned int uevent_suppress:1;
};
extern int kobject_set_name(struct kobject *kobj, const char *name, ...)
__attribute__((format(printf, 2, 3)));
extern int kobject_set_name_vargs(struct kobject *kobj, const char *fmt,
va_list vargs);
static inline const char *kobject_name(const struct kobject *kobj)
{
return kobj->name;
}
extern void kobject_init(struct kobject *kobj, struct kobj_type *ktype);
extern int __must_check kobject_add(struct kobject *kobj,
struct kobject *parent,
const char *fmt, ...);
extern int __must_check kobject_init_and_add(struct kobject *kobj,
struct kobj_type *ktype,
struct kobject *parent,
const char *fmt, ...);
extern void kobject_del(struct kobject *kobj);
extern struct kobject * __must_check kobject_create(void);
extern struct kobject * __must_check kobject_create_and_add(const char *name,
struct kobject *parent);
extern int __must_check kobject_rename(struct kobject *, const char *new_name);
extern int __must_check kobject_move(struct kobject *, struct kobject *);
extern struct kobject *kobject_get(struct kobject *kobj);
extern void kobject_put(struct kobject *kobj);
extern char *kobject_get_path(struct kobject *kobj, gfp_t flag);
struct kobj_type {
void (*release)(struct kobject *kobj);
const struct sysfs_ops *sysfs_ops;
struct attribute **default_attrs;
};
struct kobj_uevent_env {
char *envp[UEVENT_NUM_ENVP];
int envp_idx;
char buf[UEVENT_BUFFER_SIZE];
int buflen;
};
struct kset_uevent_ops {
int (* const filter)(struct kset *kset, struct kobject *kobj);
const char *(* const name)(struct kset *kset, struct kobject *kobj);
int (* const uevent)(struct kset *kset, struct kobject *kobj,
struct kobj_uevent_env *env);
};
struct kobj_attribute {
struct attribute attr;
ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr,
char *buf);
ssize_t (*store)(struct kobject *kobj, struct kobj_attribute *attr,
const char *buf, size_t count);
};
extern const struct sysfs_ops kobj_sysfs_ops;
/**
* struct kset - a set of kobjects of a specific type, belonging to a specific subsystem.
*
* A kset defines a group of kobjects. They can be individually
* different "types" but overall these kobjects all want to be grouped
* together and operated on in the same manner. ksets are used to
* define the attribute callbacks and other common events that happen to
* a kobject.
*
* @list: the list of all kobjects for this kset
* @list_lock: a lock for iterating over the kobjects
* @kobj: the embedded kobject for this kset (recursion, isn't it fun...)
* @uevent_ops: the set of uevent operations for this kset. These are
* called whenever a kobject has something happen to it so that the kset
* can add new environment variables, or filter out the uevents if so
* desired.
*/
struct kset {
struct list_head list;
spinlock_t list_lock;
struct kobject kobj;
const struct kset_uevent_ops *uevent_ops;
};
extern void kset_init(struct kset *kset);
extern int __must_check kset_register(struct kset *kset);
extern void kset_unregister(struct kset *kset);
extern struct kset * __must_check kset_create_and_add(const char *name,
const struct kset_uevent_ops *u,
struct kobject *parent_kobj);
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 *kobj)
{
return kobj->ktype;
}
extern struct kobject *kset_find_obj(struct kset *, const char *);
/* The global /sys/kernel/ kobject for people to chain off of */
extern struct kobject *kernel_kobj;
/* The global /sys/kernel/mm/ kobject for people to chain off of */
extern struct kobject *mm_kobj;
/* The global /sys/hypervisor/ kobject for people to chain off of */
extern struct kobject *hypervisor_kobj;
/* The global /sys/power/ kobject for people to chain off of */
extern struct kobject *power_kobj;
/* The global /sys/firmware/ kobject for people to chain off of */
extern struct kobject *firmware_kobj;
#if defined(CONFIG_HOTPLUG)
int kobject_uevent(struct kobject *kobj, enum kobject_action action);
int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
char *envp[]);
int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...)
__attribute__((format (printf, 2, 3)));
int kobject_action_type(const char *buf, size_t count,
enum kobject_action *type);
#else
static inline int kobject_uevent(struct kobject *kobj,
enum kobject_action action)
{ return 0; }
static inline int kobject_uevent_env(struct kobject *kobj,
enum kobject_action action,
char *envp[])
{ return 0; }
static inline int add_uevent_var(struct kobj_uevent_env *env,
const char *format, ...)
{ return 0; }
static inline int kobject_action_type(const char *buf, size_t count,
enum kobject_action *type)
{ return -EINVAL; }
#endif
#endif /* _KOBJECT_H_ */