huawei-mrd-kernel/include/linux/dcookies.h

68 lines
1.2 KiB
C

/*
* dcookies.h
*
* Persistent cookie-path mappings
*
* Copyright 2002 John Levon <levon@movementarian.org>
*/
#ifndef DCOOKIES_H
#define DCOOKIES_H
#ifdef CONFIG_PROFILING
#include <linux/dcache.h>
#include <linux/types.h>
struct dcookie_user;
struct path;
/**
* dcookie_register - register a user of dcookies
*
* Register as a dcookie user. Returns %NULL on failure.
*/
struct dcookie_user * dcookie_register(void);
/**
* dcookie_unregister - unregister a user of dcookies
*
* Unregister as a dcookie user. This may invalidate
* any dcookie values returned from get_dcookie().
*/
void dcookie_unregister(struct dcookie_user * user);
/**
* get_dcookie - acquire a dcookie
*
* Convert the given dentry/vfsmount pair into
* a cookie value.
*
* Returns -EINVAL if no living task has registered as a
* dcookie user.
*
* Returns 0 on success, with *cookie filled in
*/
int get_dcookie(struct path *path, unsigned long *cookie);
#else
static inline struct dcookie_user * dcookie_register(void)
{
return NULL;
}
static inline void dcookie_unregister(struct dcookie_user * user)
{
return;
}
static inline int get_dcookie(struct path *path, unsigned long *cookie)
{
return -ENOSYS;
}
#endif /* CONFIG_PROFILING */
#endif /* DCOOKIES_H */