12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_ERR_H
#define _LINUX_ERR_H

#include <linux/compiler.h>
#include <linux/types.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 normal
 * 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((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO)

static inline void * __must_check ERR_PTR(long error)
	return (void *) error;

static inline long __must_check PTR_ERR(__force const void *ptr)
	return (long) ptr;

static inline bool __must_check IS_ERR(__force const void *ptr)
	return IS_ERR_VALUE((unsigned long)ptr);

static inline bool __must_check IS_ERR_OR_NULL(__force const void *ptr)
	return unlikely(!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(__force const void *ptr)
	/* cast away the const */
	return (void *) ptr;

static inline int __must_check PTR_ERR_OR_ZERO(__force const void *ptr)
	if (IS_ERR(ptr))
		return PTR_ERR(ptr);
		return 0;

/* Deprecated */
#define PTR_RET(p) PTR_ERR_OR_ZERO(p)


#endif /* _LINUX_ERR_H */