/* * dcookies.h * * Persistent cookie-path mappings * * Copyright 2002 John Levon <levon@movementarian.org> */ #ifndef DCOOKIES_H #define DCOOKIES_H #include <linux/config.h> #ifdef CONFIG_PROFILING #include <linux/types.h> struct dcookie_user; /** * 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 dentry * dentry, struct vfsmount * vfsmnt, unsigned long * cookie); #else struct dcookie_user * dcookie_register(void) { return NULL; } void dcookie_unregister(struct dcookie_user * user) { return; } static inline int get_dcookie(struct dentry * dentry, struct vfsmount * vfsmnt, unsigned long * cookie) { return -ENOSYS; } #endif /* CONFIG_PROFILING */ #endif /* DCOOKIES_H */