/*
* dcookies.h
*
* Persistent cookie-path mappings
*
* Copyright 2002 John Levon <[email protected]>
*/

#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 */