Cregit: Linux 5.16: err.h

Contributors: 12
Author	Tokens	Token Proportion	Commits	Commit Proportion
Linus Torvalds	79	42.93%	3	21.43%
Uwe Kleine-König	29	15.76%	1	7.14%
Phil Carmody	24	13.04%	1	7.14%
David Howells	22	11.96%	1	7.14%
Joe Perches	6	3.26%	1	7.14%
Jani Nikula	5	2.72%	1	7.14%
Randy Dunlap	5	2.72%	1	7.14%
Dan Carpenter	5	2.72%	1	7.14%
Ralf Baechle	4	2.17%	1	7.14%
Viresh Kumar	3	1.63%	1	7.14%
Rusty Russell	1	0.54%	1	7.14%
Greg Kroah-Hartman	1	0.54%	1	7.14%
Total	184		14

/* 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);
	else
		return 0;
}

#endif

#endif /* _LINUX_ERR_H */