1 #ifndef _LINUX_ERR_H 2 #define _LINUX_ERR_H 3 4 #include <linux/compiler.h> 5 6 #include <asm/errno.h> 7 8 /* 9 * Kernel pointers have redundant information, so we can use a 10 * scheme where we can return either an error code or a dentry 11 * pointer with the same return value. 12 * 13 * This should be a per-architecture thing, to allow different 14 * error and pointer decisions. 15 */ 16 #define MAX_ERRNO 4095 17 18 #define IS_ERR_VALUE(x) unlikely((x) >= (unsigned long)-MAX_ERRNO) 19 20 static inline void *ERR_PTR(long error) 21 { 22 return (void *) error; 23 } 24 25 static inline long PTR_ERR(const void *ptr) 26 { 27 return (long) ptr; 28 } 29 30 static inline long IS_ERR(const void *ptr) 31 { 32 return IS_ERR_VALUE((unsigned long)ptr); 33 } 34 35 #endif /* _LINUX_ERR_H */ 36