linux-mm / page-reclaim / cd52d1ee9a92587b242d946a2300a3245d3b885a / . / include / asm-alpha / checksum.h

#ifndef _ALPHA_CHECKSUM_H | |

#define _ALPHA_CHECKSUM_H | |

#include <linux/in6.h> | |

/* | |

* 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); | |

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); | |

/* | |

* 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_from_user(const char __user *src, char *dst, int len, unsigned int sum, int *errp); | |

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; | |

} | |

#define _HAVE_ARCH_IPV6_CSUM | |

extern unsigned short int csum_ipv6_magic(struct in6_addr *saddr, | |

struct in6_addr *daddr, | |

__u32 len, | |

unsigned short proto, | |

unsigned int sum); | |

#endif |