mirror of
https://github.com/adulau/aha.git
synced 2024-12-29 12:16:20 +00:00
aa9c33b496
Avoid conditional branch instructions during carry bit additions. Special thanks to Bernd. Simplify: Use ((len + proto) << 8) like every other __LITTLE_ENDIAN__ machine Cc: Bernd Schmidt <bernds_cb1@t-online.de> Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> Signed-off-by: Bryan Wu <cooloney@kernel.org>
101 lines
2.4 KiB
C
101 lines
2.4 KiB
C
#ifndef _BFIN_CHECKSUM_H
|
|
#define _BFIN_CHECKSUM_H
|
|
|
|
/*
|
|
* MODIFIED FOR BFIN April 30, 2001 akbar.hussain@lineo.com
|
|
*
|
|
* 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(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);
|
|
|
|
#define csum_partial_copy_nocheck(src, dst, len, sum) \
|
|
csum_partial_copy((src), (dst), (len), (sum))
|
|
|
|
__sum16 ip_fast_csum(unsigned char *iph, unsigned int ihl);
|
|
|
|
/*
|
|
* Fold a partial checksum
|
|
*/
|
|
|
|
static inline __sum16 csum_fold(__wsum sum)
|
|
{
|
|
while (sum >> 16)
|
|
sum = (sum & 0xffff) + (sum >> 16);
|
|
return ((~(sum << 16)) >> 16);
|
|
}
|
|
|
|
/*
|
|
* 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)
|
|
{
|
|
unsigned int carry;
|
|
|
|
__asm__ ("%0 = %0 + %2;\n\t"
|
|
"CC = AC0;\n\t"
|
|
"%1 = CC;\n\t"
|
|
"%0 = %0 + %1;\n\t"
|
|
"%0 = %0 + %3;\n\t"
|
|
"CC = AC0;\n\t"
|
|
"%1 = CC;\n\t"
|
|
"%0 = %0 + %1;\n\t"
|
|
"%0 = %0 + %4;\n\t"
|
|
"CC = AC0;\n\t"
|
|
"%1 = CC;\n\t"
|
|
"%0 = %0 + %1;\n\t"
|
|
: "=d" (sum), "=&d" (carry)
|
|
: "d" (daddr), "d" (saddr), "d" ((len + proto) << 8), "0"(sum)
|
|
: "CC");
|
|
|
|
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 /* _BFIN_CHECKSUM_H */
|