/* $Id: checksum.h,v 1.19 2002/02/09 19:49:31 davem Exp $ */
#ifndef __SPARC64_CHECKSUM_H
#define __SPARC64_CHECKSUM_H
/* checksum.h: IP/UDP/TCP checksum routines on the V9.
*
* Copyright(C) 1995 Linus Torvalds
* Copyright(C) 1995 Miguel de Icaza
* Copyright(C) 1996 David S. Miller
* Copyright(C) 1996 Eddie C. Dost
* Copyright(C) 1997 Jakub Jelinek
*
* derived from:
* Alpha checksum c-code
* ix86 inline assembly
* RFC1071 Computing the Internet Checksum
*/
#include <linux/in6.h>
#include <asm/uaccess.h>
/* 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 user space while it
* checksums
*
* here even more important to align src and dst on a 32-bit (or even
* better 64-bit) boundary
*/
extern __wsum csum_partial_copy_nocheck(const void *src, void *dst,
int len, __wsum sum);
extern long __csum_partial_copy_from_user(const void __user *src,
void *dst, int len,
__wsum sum);
static inline __wsum
csum_partial_copy_from_user(const void __user *src,
void *dst, int len,
__wsum sum, int *err)
{
long ret = __csum_partial_copy_from_user(src, dst, len, sum);
if (ret < 0)
*err = -EFAULT;
return (__force __wsum) ret;
}
/*
* Copy and checksum to user
*/
#define HAVE_CSUM_COPY_USER
extern long __csum_partial_copy_to_user(const void *src,
void __user *dst, int len,
__wsum sum);
static inline __wsum
csum_and_copy_to_user(const void *src,
void __user *dst, int len,
__wsum sum, int *err)
{
long ret = __csum_partial_copy_to_user(src, dst, len, sum);
if (ret < 0)
*err = -EFAULT;
return (__force __wsum) ret;
}
/* ihl is always 5 or greater, almost always is 5, and iph is word aligned
* the majority of the time.
*/
extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
/* Fold a partial checksum without adding pseudo headers. */
static inline __sum16 csum_fold(__wsum sum)
{
unsigned int tmp;
__asm__ __volatile__(
" addcc %0, %1, %1\n"
" srl %1, 16, %1\n"
" addc %1, %%g0, %1\n"
" xnor %%g0, %1, %0\n"
: "=&r" (sum), "=r" (tmp)
: "0" (sum), "1" ((__force u32)sum<<16)
: "cc");
return (__force __sum16)sum;
}
static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
unsigned int len,
unsigned short proto,
__wsum sum)
{
__asm__ __volatile__(
" addcc %1, %0, %0\n"
" addccc %2, %0, %0\n"
" addccc %3, %0, %0\n"
" addc %0, %%g0, %0\n"
: "=r" (sum), "=r" (saddr)
: "r" (daddr), "r" (proto + len), "0" (sum), "1" (saddr)
: "cc");
return sum;
}
/*
* computes the checksum of the TCP/UDP pseudo-header
* returns a 16-bit checksum, already complemented
*/
static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
unsigned short len,
unsigned short proto,
__wsum sum)
{
return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
}
#define _HAVE_ARCH_IPV6_CSUM
static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
const struct in6_addr *daddr,
__u32 len, unsigned short proto,
__wsum sum)
{
__asm__ __volatile__ (
" addcc %3, %4, %%g7\n"
" addccc %5, %%g7, %%g7\n"
" lduw [%2 + 0x0c], %%g2\n"
" lduw [%2 + 0x08], %%g3\n"
" addccc %%g2, %%g7, %%g7\n"
" lduw [%2 + 0x04], %%g2\n"
" addccc %%g3, %%g7, %%g7\n"
" lduw [%2 + 0x00], %%g3\n"
" addccc %%g2, %%g7, %%g7\n"
" lduw [%1 + 0x0c], %%g2\n"
" addccc %%g3, %%g7, %%g7\n"
" lduw [%1 + 0x08], %%g3\n"
" addccc %%g2, %%g7, %%g7\n"
" lduw [%1 + 0x04], %%g2\n"
" addccc %%g3, %%g7, %%g7\n"
" lduw [%1 + 0x00], %%g3\n"
" addccc %%g2, %%g7, %%g7\n"
" addccc %%g3, %%g7, %0\n"
" addc 0, %0, %0\n"
: "=&r" (sum)
: "r" (saddr), "r" (daddr), "r"(htonl(len)),
"r"(htonl(proto)), "r"(sum)
: "g2", "g3", "g7", "cc");
return csum_fold(sum);
}
/* this routine is used for miscellaneous IP-like checksums, mainly in icmp.c */
static inline __sum16 ip_compute_csum(const void *buff, int len)
{
return csum_fold(csum_partial(buff, len, 0));
}
#endif /* !(__SPARC64_CHECKSUM_H) */
