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linux/include/asm-m68knommu/checksum.h
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
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!
2005-04-16 15:20:36 -07:00

134 lines
3.2 KiB
C

#ifndef _M68K_CHECKSUM_H
#define _M68K_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))
unsigned short ip_fast_csum(unsigned char *iph, unsigned int ihl);
/*
* Fold a partial checksum
*/
static inline unsigned int csum_fold(unsigned int sum)
{
#ifdef CONFIG_COLDFIRE
sum = (sum & 0xffff) + (sum >> 16);
sum = (sum & 0xffff) + (sum >> 16);
#else
unsigned int tmp = sum;
__asm__("swap %1\n\t"
"addw %1, %0\n\t"
"clrw %1\n\t"
"addxw %1, %0"
: "=&d" (sum), "=&d" (tmp)
: "0" (sum), "1" (sum));
#endif
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__ ("addl %1,%0\n\t"
"addxl %4,%0\n\t"
"addxl %5,%0\n\t"
"clrl %1\n\t"
"addxl %1,%0"
: "=&d" (sum), "=&d" (saddr)
: "0" (daddr), "1" (saddr), "d" (len + proto),
"d"(sum));
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)
{
register unsigned long tmp;
__asm__("addl %2@,%0\n\t"
"movel %2@(4),%1\n\t"
"addxl %1,%0\n\t"
"movel %2@(8),%1\n\t"
"addxl %1,%0\n\t"
"movel %2@(12),%1\n\t"
"addxl %1,%0\n\t"
"movel %3@,%1\n\t"
"addxl %1,%0\n\t"
"movel %3@(4),%1\n\t"
"addxl %1,%0\n\t"
"movel %3@(8),%1\n\t"
"addxl %1,%0\n\t"
"movel %3@(12),%1\n\t"
"addxl %1,%0\n\t"
"addxl %4,%0\n\t"
"clrl %1\n\t"
"addxl %1,%0"
: "=&d" (sum), "=&d" (tmp)
: "a" (saddr), "a" (daddr), "d" (len + proto),
"0" (sum));
return csum_fold(sum);
}
#endif /* _M68K_CHECKSUM_H */