#ifndef _LINUX_ERR_H #define _LINUX_ERR_H #include <linux/compiler.h> #include <asm/errno.h> /* * Kernel pointers have redundant information, so we can use a * scheme where we can return either an error code or a dentry * pointer with the same return value. * * This should be a per-architecture thing, to allow different * error and pointer decisions. */ #define MAX_ERRNO 4095 #ifndef __ASSEMBLY__ #define IS_ERR_VALUE(x) unlikely((x) >= (unsigned long)-MAX_ERRNO) static inline void * __must_check ERR_PTR(long error) { return (void *) error; } static inline long __must_check PTR_ERR(const void *ptr) { return (long) ptr; } static inline long __must_check IS_ERR(const void *ptr) { return IS_ERR_VALUE((unsigned long)ptr); } static inline long __must_check IS_ERR_OR_NULL(const void *ptr) { return !ptr || IS_ERR_VALUE((unsigned long)ptr); } /** * ERR_CAST - Explicitly cast an error-valued pointer to another pointer type * @ptr: The pointer to cast. * * Explicitly cast an error-valued pointer to another pointer type in such a * way as to make it clear that's what's going on. */ static inline void * __must_check ERR_CAST(const void *ptr) { /* cast away the const */ return (void *) ptr; } #endif #endif /* _LINUX_ERR_H */