treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / arch / arm64 / include / asm / checksum.h
blob8d2a7de39744236771557118e8189eb6f67441a9
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright (C) 2016 ARM Ltd.
4 */
5 #ifndef __ASM_CHECKSUM_H
6 #define __ASM_CHECKSUM_H
8 #include <linux/types.h>
10 static inline __sum16 csum_fold(__wsum csum)
12 u32 sum = (__force u32)csum;
13 sum += (sum >> 16) | (sum << 16);
14 return ~(__force __sum16)(sum >> 16);
16 #define csum_fold csum_fold
18 static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
20 __uint128_t tmp;
21 u64 sum;
23 tmp = *(const __uint128_t *)iph;
24 iph += 16;
25 ihl -= 4;
26 tmp += ((tmp >> 64) | (tmp << 64));
27 sum = tmp >> 64;
28 do {
29 sum += *(const u32 *)iph;
30 iph += 4;
31 } while (--ihl);
33 sum += ((sum >> 32) | (sum << 32));
34 return csum_fold((__force u32)(sum >> 32));
36 #define ip_fast_csum ip_fast_csum
38 extern unsigned int do_csum(const unsigned char *buff, int len);
39 #define do_csum do_csum
41 #include <asm-generic/checksum.h>
43 #endif /* __ASM_CHECKSUM_H */