Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) /* SPDX-License-Identifier: GPL-2.0 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) #ifndef __TOOLS_LINUX_ERR_H
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3) #define __TOOLS_LINUX_ERR_H
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5) #include <linux/compiler.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) #include <asm/errno.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11)  * Original kernel header comment:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)  * Kernel pointers have redundant information, so we can use a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14)  * scheme where we can return either an error code or a normal
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)  * pointer with the same return value.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)  * This should be a per-architecture thing, to allow different
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18)  * error and pointer decisions.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20)  * Userspace note:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21)  * The same principle works for userspace, because 'error' pointers
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)  * fall down to the unused hole far from user space, as described
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23)  * in Documentation/x86/x86_64/mm.rst for x86_64 arch:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25)  * 0000000000000000 - 00007fffffffffff (=47 bits) user space, different per mm hole caused by [48:63] sign extension
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26)  * ffffffffffe00000 - ffffffffffffffff (=2 MB) unused hole
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28)  * It should be the same case for other architectures, because
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29)  * this code is used in generic kernel code.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) #define MAX_ERRNO	4095
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) #define IS_ERR_VALUE(x) unlikely((x) >= (unsigned long)-MAX_ERRNO)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) static inline void * __must_check ERR_PTR(long error_)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 	return (void *) error_;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) static inline long __must_check PTR_ERR(__force const void *ptr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 	return (long) ptr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) static inline bool __must_check IS_ERR(__force const void *ptr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 	return IS_ERR_VALUE((unsigned long)ptr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) static inline bool __must_check IS_ERR_OR_NULL(__force const void *ptr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 	return unlikely(!ptr) || IS_ERR_VALUE((unsigned long)ptr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) static inline int __must_check PTR_ERR_OR_ZERO(__force const void *ptr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 	if (IS_ERR(ptr))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 		return PTR_ERR(ptr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 	else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64)  * ERR_CAST - Explicitly cast an error-valued pointer to another pointer type
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65)  * @ptr: The pointer to cast.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67)  * Explicitly cast an error-valued pointer to another pointer type in such a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68)  * way as to make it clear that's what's going on.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) static inline void * __must_check ERR_CAST(__force const void *ptr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) 	/* cast away the const */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 	return (void *) ptr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) #endif /* _LINUX_ERR_H */