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#ifdef __KERNEL__
#ifndef _ASM_M32R_CHECKSUM_H
#define _ASM_M32R_CHECKSUM_H
/*
* include/asm-m32r/checksum.h
*
* IP/TCP/UDP checksum routines
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Some code taken from mips and parisc architecture.
*
* Copyright (C) 2001, 2002 Hiroyuki Kondo, Hirokazu Takata
* Copyright (C) 2004 Hirokazu Takata <takata at linux-m32r.org>
*/
#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
*/
asmlinkage 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
*/
extern unsigned int csum_partial_copy_nocheck(const unsigned char *src,
unsigned char *dst,
int len, unsigned int sum);
/*
* This is a new version of the above that records errors it finds in *errp,
* but continues and zeros thre rest of the buffer.
*/
extern unsigned int csum_partial_copy_from_user(const unsigned char __user *src,
unsigned char *dst,
int len, unsigned int sum,
int *err_ptr);
/*
* Fold a partial checksum
*/
static inline unsigned int csum_fold(unsigned int sum)
{
unsigned long tmpreg;
__asm__(
" sll3 %1, %0, #16 \n"
" cmp %0, %0 \n"
" addx %0, %1 \n"
" ldi %1, #0 \n"
" srli %0, #16 \n"
" addx %0, %1 \n"
" xor3 %0, %0, #0x0000ffff \n"
: "=r" (sum), "=&r" (tmpreg)
: "0" (sum)
: "cbit"
);
return 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 long sum, tmpreg0, tmpreg1;
__asm__ __volatile__(
" ld %0, @%1+ \n"
" addi %2, #-4 \n"
"# bgez %2, 2f \n"
" cmp %0, %0 \n"
" ld %3, @%1+ \n"
" ld %4, @%1+ \n"
" addx %0, %3 \n"
" ld %3, @%1+ \n"
" addx %0, %4 \n"
" addx %0, %3 \n"
" .fillinsn\n"
"1: \n"
" ld %4, @%1+ \n"
" addi %2, #-1 \n"
" addx %0, %4 \n"
" bgtz %2, 1b \n"
"\n"
" ldi %3, #0 \n"
" addx %0, %3 \n"
" .fillinsn\n"
"2: \n"
/* Since the input registers which are loaded with iph and ihl
are modified, we must also specify them as outputs, or gcc
will assume they contain their original values. */
: "=&r" (sum), "=r" (iph), "=r" (ihl), "=&r" (tmpreg0), "=&r" (tmpreg1)
: "1" (iph), "2" (ihl)
: "cbit", "memory");
return csum_fold(sum);
}
static inline unsigned long csum_tcpudp_nofold(unsigned long saddr,
unsigned long daddr,
unsigned short len,
unsigned short proto,
unsigned int sum)
{
#if defined(__LITTLE_ENDIAN)
unsigned long len_proto = (ntohs(len)<<16)+proto*256;
#else
unsigned long len_proto = (proto<<16)+len;
#endif
unsigned long tmpreg;
__asm__(
" cmp %0, %0 \n"
" addx %0, %2 \n"
" addx %0, %3 \n"
" addx %0, %4 \n"
" ldi %1, #0 \n"
" addx %0, %1 \n"
: "=r" (sum), "=&r" (tmpreg)
: "r" (daddr), "r" (saddr), "r" (len_proto), "0" (sum)
: "cbit"
);
return sum;
}
/*
* computes the checksum of the TCP/UDP pseudo-header
* returns a 16-bit checksum, already complemented
*/
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
*/
static inline unsigned short ip_compute_csum(unsigned char * buff, int len) {
return csum_fold (csum_partial(buff, len, 0));
}
#define _HAVE_ARCH_IPV6_CSUM
static inline unsigned short int csum_ipv6_magic(struct in6_addr *saddr,
struct in6_addr *daddr,
__u16 len,
unsigned short proto,
unsigned int sum)
{
unsigned long tmpreg0, tmpreg1, tmpreg2, tmpreg3;
__asm__(
" ld %1, @(%5) \n"
" ld %2, @(4,%5) \n"
" ld %3, @(8,%5) \n"
" ld %4, @(12,%5) \n"
" add %0, %1 \n"
" addx %0, %2 \n"
" addx %0, %3 \n"
" addx %0, %4 \n"
" ld %1, @(%6) \n"
" ld %2, @(4,%6) \n"
" ld %3, @(8,%6) \n"
" ld %4, @(12,%6) \n"
" addx %0, %1 \n"
" addx %0, %2 \n"
" addx %0, %3 \n"
" addx %0, %4 \n"
" addx %0, %7 \n"
" addx %0, %8 \n"
" ldi %1, #0 \n"
" addx %0, %1 \n"
: "=&r" (sum), "=&r" (tmpreg0), "=&r" (tmpreg1),
"=&r" (tmpreg2), "=&r" (tmpreg3)
: "r" (saddr), "r" (daddr),
"r" (htonl((__u32) (len))), "r" (htonl(proto)), "0" (sum)
: "cbit"
);
return csum_fold(sum);
}
#endif /* _ASM_M32R_CHECKSUM_H */
#endif /* __KERNEL__ */
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