1#ifndef _LINUX_ERR_H
 2#define _LINUX_ERR_H
 3
 4#include <linux/compiler.h>
 5#include <linux/types.h>
 6
 7#include <asm/errno.h>
 8
 9/*
10 * Kernel pointers have redundant information, so we can use a
11 * scheme where we can return either an error code or a normal
12 * pointer with the same return value.
13 *
14 * This should be a per-architecture thing, to allow different
15 * error and pointer decisions.
16 */
17#define MAX_ERRNO	4095
18
19#ifndef __ASSEMBLY__
20
21#define IS_ERR_VALUE(x) unlikely((x) >= (unsigned long)-MAX_ERRNO)
22
23static inline void * __must_check ERR_PTR(long error)
24{
25	return (void *) error;
26}
27
28static inline long __must_check PTR_ERR(__force const void *ptr)
29{
30	return (long) ptr;
31}
32
33static inline bool __must_check IS_ERR(__force const void *ptr)
34{
35	return IS_ERR_VALUE((unsigned long)ptr);
36}
37
38static inline bool __must_check IS_ERR_OR_NULL(__force const void *ptr)
39{
40	return !ptr || IS_ERR_VALUE((unsigned long)ptr);
41}
42
43/**
44 * ERR_CAST - Explicitly cast an error-valued pointer to another pointer type
45 * @ptr: The pointer to cast.
46 *
47 * Explicitly cast an error-valued pointer to another pointer type in such a
48 * way as to make it clear that's what's going on.
49 */
50static inline void * __must_check ERR_CAST(__force const void *ptr)
51{
52	/* cast away the const */
53	return (void *) ptr;
54}
55
56static inline int __must_check PTR_ERR_OR_ZERO(__force const void *ptr)
57{
58	if (IS_ERR(ptr))
59		return PTR_ERR(ptr);
60	else
61		return 0;
62}
63
64/* Deprecated */
65#define PTR_RET(p) PTR_ERR_OR_ZERO(p)
66
67#endif
68
69#endif /* _LINUX_ERR_H */

 1/* SPDX-License-Identifier: GPL-2.0 */
 2#ifndef _LINUX_ERR_H
 3#define _LINUX_ERR_H
 4
 5#include <linux/compiler.h>
 6#include <linux/types.h>
 7
 8#include <asm/errno.h>
 9
10/*
11 * Kernel pointers have redundant information, so we can use a
12 * scheme where we can return either an error code or a normal
13 * pointer with the same return value.
14 *
15 * This should be a per-architecture thing, to allow different
16 * error and pointer decisions.
17 */
18#define MAX_ERRNO	4095
19
20#ifndef __ASSEMBLY__
21
22#define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO)
23
24static inline void * __must_check ERR_PTR(long error)
25{
26	return (void *) error;
27}
28
29static inline long __must_check PTR_ERR(__force const void *ptr)
30{
31	return (long) ptr;
32}
33
34static inline bool __must_check IS_ERR(__force const void *ptr)
35{
36	return IS_ERR_VALUE((unsigned long)ptr);
37}
38
39static inline bool __must_check IS_ERR_OR_NULL(__force const void *ptr)
40{
41	return unlikely(!ptr) || IS_ERR_VALUE((unsigned long)ptr);
42}
43
44/**
45 * ERR_CAST - Explicitly cast an error-valued pointer to another pointer type
46 * @ptr: The pointer to cast.
47 *
48 * Explicitly cast an error-valued pointer to another pointer type in such a
49 * way as to make it clear that's what's going on.
50 */
51static inline void * __must_check ERR_CAST(__force const void *ptr)
52{
53	/* cast away the const */
54	return (void *) ptr;
55}
56
57static inline int __must_check PTR_ERR_OR_ZERO(__force const void *ptr)
58{
59	if (IS_ERR(ptr))
60		return PTR_ERR(ptr);
61	else
62		return 0;
63}
64
65/* Deprecated */
66#define PTR_RET(p) PTR_ERR_OR_ZERO(p)
67
68#endif
69
70#endif /* _LINUX_ERR_H */