aha/include/asm-ia64/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

76 lines
2.1 KiB
C

#ifndef _ASM_IA64_CHECKSUM_H
#define _ASM_IA64_CHECKSUM_H
/*
* Modified 1998, 1999
* David Mosberger-Tang <davidm@hpl.hp.com>, Hewlett-Packard Co
*/
/*
* This is a version of ip_compute_csum() optimized for IP headers,
* which always checksum on 4 octet boundaries.
*/
extern unsigned short ip_fast_csum (unsigned char * iph, unsigned int ihl);
/*
* Computes the checksum of the TCP/UDP pseudo-header returns a 16-bit
* checksum, already complemented
*/
extern unsigned short int csum_tcpudp_magic (unsigned long saddr,
unsigned long daddr,
unsigned short len,
unsigned short proto,
unsigned int sum);
extern unsigned int csum_tcpudp_nofold (unsigned long saddr,
unsigned long daddr,
unsigned short len,
unsigned short proto,
unsigned int sum);
/*
* 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
*/
extern unsigned int csum_partial (const unsigned char * buff, int len,
unsigned int sum);
/*
* Same as csum_partial, but copies from src while it checksums.
*
* Here it is 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, unsigned int sum,
int *errp);
extern unsigned int csum_partial_copy_nocheck (const char *src, char *dst,
int len, unsigned int sum);
/*
* This routine is used for miscellaneous IP-like checksums, mainly in
* icmp.c
*/
extern unsigned short ip_compute_csum (unsigned char *buff, int len);
/*
* Fold a partial checksum without adding pseudo headers.
*/
static inline unsigned short
csum_fold (unsigned int sum)
{
sum = (sum & 0xffff) + (sum >> 16);
sum = (sum & 0xffff) + (sum >> 16);
return ~sum;
}
#endif /* _ASM_IA64_CHECKSUM_H */