xref: /openbmc/linux/arch/ia64/include/asm/checksum.h (revision 0da85d1e)
1 #ifndef _ASM_IA64_CHECKSUM_H
2 #define _ASM_IA64_CHECKSUM_H
3 
4 /*
5  * Modified 1998, 1999
6  *	David Mosberger-Tang <davidm@hpl.hp.com>, Hewlett-Packard Co
7  */
8 
9 /*
10  * This is a version of ip_compute_csum() optimized for IP headers,
11  * which always checksum on 4 octet boundaries.
12  */
13 extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
14 
15 /*
16  * Computes the checksum of the TCP/UDP pseudo-header returns a 16-bit
17  * checksum, already complemented
18  */
19 extern __sum16 csum_tcpudp_magic (__be32 saddr, __be32 daddr,
20 					     unsigned short len,
21 					     unsigned short proto,
22 					     __wsum sum);
23 
24 extern __wsum csum_tcpudp_nofold (__be32 saddr, __be32 daddr,
25 					unsigned short len,
26 					unsigned short proto,
27 					__wsum sum);
28 
29 /*
30  * Computes the checksum of a memory block at buff, length len,
31  * and adds in "sum" (32-bit)
32  *
33  * returns a 32-bit number suitable for feeding into itself
34  * or csum_tcpudp_magic
35  *
36  * this function must be called with even lengths, except
37  * for the last fragment, which may be odd
38  *
39  * it's best to have buff aligned on a 32-bit boundary
40  */
41 extern __wsum csum_partial(const void *buff, int len, __wsum sum);
42 
43 /*
44  * Same as csum_partial, but copies from src while it checksums.
45  *
46  * Here it is even more important to align src and dst on a 32-bit (or
47  * even better 64-bit) boundary.
48  */
49 extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst,
50 						 int len, __wsum sum,
51 						 int *errp);
52 
53 extern __wsum csum_partial_copy_nocheck(const void *src, void *dst,
54 					       int len, __wsum sum);
55 
56 /*
57  * This routine is used for miscellaneous IP-like checksums, mainly in
58  * icmp.c
59  */
60 extern __sum16 ip_compute_csum(const void *buff, int len);
61 
62 /*
63  * Fold a partial checksum without adding pseudo headers.
64  */
65 static inline __sum16 csum_fold(__wsum csum)
66 {
67 	u32 sum = (__force u32)csum;
68 	sum = (sum & 0xffff) + (sum >> 16);
69 	sum = (sum & 0xffff) + (sum >> 16);
70 	return (__force __sum16)~sum;
71 }
72 
73 #define _HAVE_ARCH_IPV6_CSUM	1
74 struct in6_addr;
75 extern __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
76 	const struct in6_addr *daddr, __u32 len, unsigned short proto,
77 	__wsum csum);
78 
79 #endif /* _ASM_IA64_CHECKSUM_H */
80