blob: 5ede82432d2d26efeb0d402482f6483202db152d (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
|
#ifndef _LINUX_ERR_H
#define _LINUX_ERR_H
#include <linux/compiler.h>
#include <linux/compat.h>
#include <linux/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 *ERR_PTR(long error)
{
return (void *)(CONFIG_ERR_PTR_OFFSET + error);
}
static inline long PTR_ERR(const void *ptr)
{
return ((long)ptr - CONFIG_ERR_PTR_OFFSET);
}
static inline long IS_ERR(const void *ptr)
{
return IS_ERR_VALUE((unsigned long)PTR_ERR(ptr));
}
static inline bool IS_ERR_OR_NULL(const void *ptr)
{
return !ptr || IS_ERR_VALUE((unsigned long)PTR_ERR(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;
}
#endif
#endif /* _LINUX_ERR_H */
|