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#ifndef _H8300_CHECKSUM_H
#define _H8300_CHECKSUM_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
*/
__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_nocheck(const void *src, void *dst, int len, __wsum 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 __wsum csum_partial_copy_from_user(const void __user *src, void *dst,
int len, __wsum sum, int *csum_err);
__sum16 ip_fast_csum(const void *iph, unsigned int ihl);
/*
* Fold a partial checksum
*/
static inline __sum16 csum_fold(__wsum sum)
{
__asm__("mov.l %0,er0\n\t"
"add.w e0,r0\n\t"
"xor.w e0,e0\n\t"
"rotxl.w e0\n\t"
"add.w e0,r0\n\t"
"sub.w e0,e0\n\t"
"mov.l er0,%0"
: "=r"(sum)
: "0"(sum)
: "er0");
return (__force __sum16)~sum;
}
/*
* computes the checksum of the TCP/UDP pseudo-header
* returns a 16-bit checksum, already complemented
*/
static inline __wsum
csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len,
unsigned short proto, __wsum sum)
{
__asm__ ("sub.l er0,er0\n\t"
"add.l %2,%0\n\t"
"addx #0,r0l\n\t"
"add.l %3,%0\n\t"
"addx #0,r0l\n\t"
"add.l %4,%0\n\t"
"addx #0,r0l\n\t"
"add.l er0,%0\n\t"
"bcc 1f\n\t"
"inc.l #1,%0\n"
"1:"
: "=&r" (sum)
: "0" (sum), "r" (daddr), "r" (saddr), "r" (len + proto)
:"er0");
return sum;
}
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));
}
/*
* this routine is used for miscellaneous IP-like checksums, mainly
* in icmp.c
*/
extern __sum16 ip_compute_csum(const void *buff, int len);
#endif /* _H8300_CHECKSUM_H */
