1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_IA64_CHECKSUM_H
3 #define _ASM_IA64_CHECKSUM_H
4
5 /*
6 * Modified 1998, 1999
7 * David Mosberger-Tang <davidm@hpl.hp.com>, Hewlett-Packard Co
8 */
9
10 /*
11 * This is a version of ip_compute_csum() optimized for IP headers,
12 * which always checksum on 4 octet boundaries.
13 */
14 extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
15
16 /*
17 * Computes the checksum of the TCP/UDP pseudo-header returns a 16-bit
18 * checksum, already complemented
19 */
20 extern __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
21 __u32 len, __u8 proto, __wsum sum);
22
23 extern __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
24 __u32 len, __u8 proto, __wsum sum);
25
26 /*
27 * Computes the checksum of a memory block at buff, length len,
28 * and adds in "sum" (32-bit)
29 *
30 * returns a 32-bit number suitable for feeding into itself
31 * or csum_tcpudp_magic
32 *
33 * this function must be called with even lengths, except
34 * for the last fragment, which may be odd
35 *
36 * it's best to have buff aligned on a 32-bit boundary
37 */
38 extern __wsum csum_partial(const void *buff, int len, __wsum sum);
39
40 /*
41 * This routine is used for miscellaneous IP-like checksums, mainly in
42 * icmp.c
43 */
44 extern __sum16 ip_compute_csum(const void *buff, int len);
45
46 /*
47 * Fold a partial checksum without adding pseudo headers.
48 */
csum_fold(__wsum csum)49 static inline __sum16 csum_fold(__wsum csum)
50 {
51 u32 sum = (__force u32)csum;
52 sum = (sum & 0xffff) + (sum >> 16);
53 sum = (sum & 0xffff) + (sum >> 16);
54 return (__force __sum16)~sum;
55 }
56
57 #define _HAVE_ARCH_IPV6_CSUM 1
58 struct in6_addr;
59 extern __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
60 const struct in6_addr *daddr,
61 __u32 len, __u8 proto, __wsum csum);
62
63 #endif /* _ASM_IA64_CHECKSUM_H */
64