1 #ifndef _ALPHA_CHECKSUM_H
2 #define _ALPHA_CHECKSUM_H
7 * This is a version of ip_compute_csum() optimized for IP headers,
8 * which always checksum on 4 octet boundaries.
10 extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
13 * computes the checksum of the TCP/UDP pseudo-header
14 * returns a 16-bit checksum, already complemented
16 __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
17 __u32 len, __u8 proto, __wsum sum);
19 __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
20 __u32 len, __u8 proto, __wsum sum);
23 * computes the checksum of a memory block at buff, length len,
24 * and adds in "sum" (32-bit)
26 * returns a 32-bit number suitable for feeding into itself
27 * or csum_tcpudp_magic
29 * this function must be called with even lengths, except
30 * for the last fragment, which may be odd
32 * it's best to have buff aligned on a 32-bit boundary
34 extern __wsum csum_partial(const void *buff, int len, __wsum sum);
37 * the same as csum_partial, but copies from src while it
40 * here even more important to align src and dst on a 32-bit (or even
41 * better 64-bit) boundary
43 __wsum csum_partial_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *errp);
45 __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum);
49 * this routine is used for miscellaneous IP-like checksums, mainly
53 extern __sum16 ip_compute_csum(const void *buff, int len);
56 * Fold a partial checksum without adding pseudo headers
59 static inline __sum16 csum_fold(__wsum csum)
61 u32 sum = (__force u32)csum;
62 sum = (sum & 0xffff) + (sum >> 16);
63 sum = (sum & 0xffff) + (sum >> 16);
64 return (__force __sum16)~sum;
67 #define _HAVE_ARCH_IPV6_CSUM
68 extern __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
69 const struct in6_addr *daddr,
70 __u32 len, __u8 proto, __wsum sum);