linux / linux / kernel / git / torvalds / linux / refs/tags/v2.6.12-rc5 / . / include / asm-ia64 / checksum.h

#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 */ |