1 #ifndef _ALPHA_CHECKSUM_H
2 #define _ALPHA_CHECKSUM_H
3
4 #include <linux/in6.h>
5
6 /*
7 * This is a version of ip_compute_csum() optimized for IP headers,
8 * which always checksum on 4 octet boundaries.
9 */
10 extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
11
12 /*
13 * computes the checksum of the TCP/UDP pseudo-header
14 * returns a 16-bit checksum, already complemented
15 */
16 extern __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
17 unsigned short len,
18 unsigned short proto,
19 __wsum sum);
20
21 __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
22 unsigned short len, unsigned short proto,
23 __wsum sum);
24
25 /*
26 * computes the checksum of a memory block at buff, length len,
27 * and adds in "sum" (32-bit)
28 *
29 * returns a 32-bit number suitable for feeding into itself
30 * or csum_tcpudp_magic
31 *
32 * this function must be called with even lengths, except
33 * for the last fragment, which may be odd
34 *
35 * it's best to have buff aligned on a 32-bit boundary
36 */
37 extern __wsum csum_partial(const void *buff, int len, __wsum sum);
38
39 /*
40 * the same as csum_partial, but copies from src while it
41 * checksums
42 *
43 * here even more important to align src and dst on a 32-bit (or even
44 * better 64-bit) boundary
45 */
46 __wsum csum_partial_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *errp);
47
48 __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum);
49
50
51 /*
52 * this routine is used for miscellaneous IP-like checksums, mainly
53 * in icmp.c
54 */
55
56 extern __sum16 ip_compute_csum(const void *buff, int len);
57
58 /*
59 * Fold a partial checksum without adding pseudo headers
60 */
61
csum_fold(__wsum csum)62 static inline __sum16 csum_fold(__wsum csum)
63 {
64 u32 sum = (__force u32)csum;
65 sum = (sum & 0xffff) + (sum >> 16);
66 sum = (sum & 0xffff) + (sum >> 16);
67 return (__force __sum16)~sum;
68 }
69
70 #define _HAVE_ARCH_IPV6_CSUM
71 extern __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
72 const struct in6_addr *daddr,
73 __u32 len, unsigned short proto,
74 __wsum sum);
75 #endif
76