linux-mm / kernel / git / torvalds / linux / 2a24ab628aa7b190be32f63dfb6d96f3fb61580a / . / include / asm-h8300 / checksum.h

#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 | |

*/ | |

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(const char *src, char *dst, int len, int 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 unsigned int csum_partial_copy_from_user(const char *src, char *dst, | |

int len, int sum, int *csum_err); | |

#define csum_partial_copy_nocheck(src, dst, len, sum) \ | |

csum_partial_copy((src), (dst), (len), (sum)) | |

unsigned short ip_fast_csum(unsigned char *iph, unsigned int ihl); | |

/* | |

* Fold a partial checksum | |

*/ | |

static inline unsigned int csum_fold(unsigned int 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 ~sum; | |

} | |

/* | |

* computes the checksum of the TCP/UDP pseudo-header | |

* returns a 16-bit checksum, already complemented | |

*/ | |

static inline unsigned int | |

csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len, | |

unsigned short proto, unsigned int 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 unsigned short int | |

csum_tcpudp_magic(unsigned long saddr, unsigned long daddr, unsigned short len, | |

unsigned short proto, unsigned int 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 unsigned short ip_compute_csum(const unsigned char * buff, int len); | |

#endif /* _H8300_CHECKSUM_H */ |