forked from Minki/linux
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
184 lines
4.7 KiB
C
184 lines
4.7 KiB
C
/* checksum.h: FRV checksumming
|
|
*
|
|
* Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#ifndef _ASM_CHECKSUM_H
|
|
#define _ASM_CHECKSUM_H
|
|
|
|
#include <linux/in6.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
|
|
*/
|
|
unsigned int csum_partial(const unsigned char * buff, int len, unsigned int 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
|
|
*/
|
|
unsigned int csum_partial_copy(const char *src, char *dst, int len, int sum);
|
|
|
|
/*
|
|
* the same as csum_partial_copy, but copies from user space.
|
|
*
|
|
* here even more important to align src and dst on a 32-bit (or even
|
|
* better 64-bit) boundary
|
|
*/
|
|
extern unsigned int csum_partial_copy_from_user(const char *src, char *dst,
|
|
int len, int sum, int *csum_err);
|
|
|
|
#define csum_partial_copy_nocheck(src, dst, len, sum) \
|
|
csum_partial_copy((src), (dst), (len), (sum))
|
|
|
|
/*
|
|
* This is a version of ip_compute_csum() optimized for IP headers,
|
|
* which always checksum on 4 octet boundaries.
|
|
*
|
|
*/
|
|
static inline
|
|
unsigned short ip_fast_csum(unsigned char *iph, unsigned int ihl)
|
|
{
|
|
unsigned int tmp, inc, sum = 0;
|
|
|
|
asm(" addcc gr0,gr0,gr0,icc0\n" /* clear icc0.C */
|
|
" subi %1,#4,%1 \n"
|
|
"0: \n"
|
|
" ldu.p @(%1,%3),%4 \n"
|
|
" subicc %2,#1,%2,icc1 \n"
|
|
" addxcc.p %4,%0,%0,icc0 \n"
|
|
" bhi icc1,#2,0b \n"
|
|
|
|
/* fold the 33-bit result into 16-bits */
|
|
" addxcc gr0,%0,%0,icc0 \n"
|
|
" srli %0,#16,%1 \n"
|
|
" sethi #0,%0 \n"
|
|
" add %1,%0,%0 \n"
|
|
" srli %0,#16,%1 \n"
|
|
" add %1,%0,%0 \n"
|
|
|
|
: "=r" (sum), "=r" (iph), "=r" (ihl), "=r" (inc), "=&r"(tmp)
|
|
: "0" (sum), "1" (iph), "2" (ihl), "3" (4),
|
|
"m"(*(volatile struct { int _[100]; } *)iph)
|
|
: "icc0", "icc1"
|
|
);
|
|
|
|
return ~sum;
|
|
}
|
|
|
|
/*
|
|
* Fold a partial checksum
|
|
*/
|
|
static inline unsigned int csum_fold(unsigned int sum)
|
|
{
|
|
unsigned int tmp;
|
|
|
|
asm(" srli %0,#16,%1 \n"
|
|
" sethi #0,%0 \n"
|
|
" add %1,%0,%0 \n"
|
|
" srli %0,#16,%1 \n"
|
|
" add %1,%0,%0 \n"
|
|
: "=r"(sum), "=&r"(tmp)
|
|
: "0"(sum)
|
|
);
|
|
|
|
return ~sum;
|
|
}
|
|
|
|
/*
|
|
* computes the checksum of the TCP/UDP pseudo-header
|
|
* returns a 16-bit checksum, already complemented
|
|
*/
|
|
static inline unsigned int
|
|
csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len,
|
|
unsigned short proto, unsigned int sum)
|
|
{
|
|
asm(" addcc %1,%0,%0,icc0 \n"
|
|
" addxcc %2,%0,%0,icc0 \n"
|
|
" addxcc %3,%0,%0,icc0 \n"
|
|
" addxcc gr0,%0,%0,icc0 \n"
|
|
: "=r" (sum)
|
|
: "r" (daddr), "r" (saddr), "r" (len + proto), "0"(sum)
|
|
: "icc0"
|
|
);
|
|
return sum;
|
|
}
|
|
|
|
static inline unsigned short int
|
|
csum_tcpudp_magic(unsigned long saddr, unsigned long daddr, unsigned short len,
|
|
unsigned short proto, unsigned int sum)
|
|
{
|
|
return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
|
|
}
|
|
|
|
/*
|
|
* this routine is used for miscellaneous IP-like checksums, mainly
|
|
* in icmp.c
|
|
*/
|
|
extern unsigned short ip_compute_csum(const unsigned char * buff, int len);
|
|
|
|
#define _HAVE_ARCH_IPV6_CSUM
|
|
static inline unsigned short int
|
|
csum_ipv6_magic(struct in6_addr *saddr, struct in6_addr *daddr,
|
|
__u32 len, unsigned short proto, unsigned int sum)
|
|
{
|
|
unsigned long tmp, tmp2;
|
|
|
|
asm(" addcc %2,%0,%0,icc0 \n"
|
|
|
|
/* add up the source addr */
|
|
" ldi @(%3,0),%1 \n"
|
|
" addxcc %1,%0,%0,icc0 \n"
|
|
" ldi @(%3,4),%2 \n"
|
|
" addxcc %2,%0,%0,icc0 \n"
|
|
" ldi @(%3,8),%1 \n"
|
|
" addxcc %1,%0,%0,icc0 \n"
|
|
" ldi @(%3,12),%2 \n"
|
|
" addxcc %2,%0,%0,icc0 \n"
|
|
|
|
/* add up the dest addr */
|
|
" ldi @(%4,0),%1 \n"
|
|
" addxcc %1,%0,%0,icc0 \n"
|
|
" ldi @(%4,4),%2 \n"
|
|
" addxcc %2,%0,%0,icc0 \n"
|
|
" ldi @(%4,8),%1 \n"
|
|
" addxcc %1,%0,%0,icc0 \n"
|
|
" ldi @(%4,12),%2 \n"
|
|
" addxcc %2,%0,%0,icc0 \n"
|
|
|
|
/* fold the 33-bit result into 16-bits */
|
|
" addxcc gr0,%0,%0,icc0 \n"
|
|
" srli %0,#16,%1 \n"
|
|
" sethi #0,%0 \n"
|
|
" add %1,%0,%0 \n"
|
|
" srli %0,#16,%1 \n"
|
|
" add %1,%0,%0 \n"
|
|
|
|
: "=r" (sum), "=&r" (tmp), "=r" (tmp2)
|
|
: "r" (saddr), "r" (daddr), "0" (sum), "2" (len + proto)
|
|
: "icc0"
|
|
);
|
|
|
|
return ~sum;
|
|
}
|
|
|
|
#endif /* _ASM_CHECKSUM_H */
|