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linux/include/asm-alpha/checksum.h
Al Viro 9be259aae5 [NET]: Alpha checksum annotations and cleanups.
* sanitize prototypes and annotate
* kill useless access_ok() in csum_partial_copy_from_user() (the only
caller checks it already).
* do_csum_partial_copy_from_user() is not needed now
* replace htons(len) with len << 8 - they are the same wrt checksums
on little-endian.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:23:01 -08:00

76 lines
2.0 KiB
C

#ifndef _ALPHA_CHECKSUM_H
#define _ALPHA_CHECKSUM_H
#include <linux/in6.h>
/*
* This is a version of ip_compute_csum() optimized for IP headers,
* which always checksum on 4 octet boundaries.
*/
extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
/*
* computes the checksum of the TCP/UDP pseudo-header
* returns a 16-bit checksum, already complemented
*/
extern __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
unsigned short len,
unsigned short proto,
__wsum sum);
__wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
unsigned short len, unsigned short proto,
__wsum sum);
/*
* computes the checksum of a memory block at buff, length len,
* and adds in "sum" (32-bit)
*
* returns a 32-bit number suitable for feeding into itself
* or csum_tcpudp_magic
*
* this function must be called with even lengths, except
* for the last fragment, which may be odd
*
* it's best to have buff aligned on a 32-bit boundary
*/
extern __wsum csum_partial(const void *buff, int len, __wsum sum);
/*
* the same as csum_partial, but copies from src while it
* checksums
*
* here even more important to align src and dst on a 32-bit (or even
* better 64-bit) boundary
*/
__wsum csum_partial_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *errp);
__wsum csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum);
/*
* this routine is used for miscellaneous IP-like checksums, mainly
* in icmp.c
*/
extern __sum16 ip_compute_csum(const void *buff, int len);
/*
* Fold a partial checksum without adding pseudo headers
*/
static inline __sum16 csum_fold(__wsum csum)
{
u32 sum = (__force u32)csum;
sum = (sum & 0xffff) + (sum >> 16);
sum = (sum & 0xffff) + (sum >> 16);
return (__force __sum16)~sum;
}
#define _HAVE_ARCH_IPV6_CSUM
extern __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
const struct in6_addr *daddr,
__u32 len, unsigned short proto,
__wsum sum);
#endif