#ifndef _M68K_CHECKSUM_H #define _M68K_CHECKSUM_H #include /* * 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 */ extern unsigned int csum_partial_copy_from_user(const unsigned char *src, unsigned char *dst, int len, int sum, int *csum_err); extern unsigned int csum_partial_copy_nocheck(const unsigned char *src, unsigned char *dst, int len, int sum); /* * This is a version of ip_compute_csum() optimized for IP headers, * which always checksum on 4 octet boundaries. * */ static inline unsigned short ip_fast_csum(unsigned char *iph, unsigned int ihl) { unsigned int sum = 0; unsigned long tmp; __asm__ ("subqw #1,%2\n" "1:\t" "movel %1@+,%3\n\t" "addxl %3,%0\n\t" "dbra %2,1b\n\t" "movel %0,%3\n\t" "swap %3\n\t" "addxw %3,%0\n\t" "clrw %3\n\t" "addxw %3,%0\n\t" : "=d" (sum), "=&a" (iph), "=&d" (ihl), "=&d" (tmp) : "0" (sum), "1" (iph), "2" (ihl) : "memory"); return ~sum; } /* * Fold a partial checksum */ static inline unsigned int csum_fold(unsigned int sum) { unsigned int tmp = sum; __asm__("swap %1\n\t" "addw %1, %0\n\t" "clrw %1\n\t" "addxw %1, %0" : "=&d" (sum), "=&d" (tmp) : "0" (sum), "1" (tmp)); return ~sum; } static inline unsigned int csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len, unsigned short proto, unsigned int sum) { __asm__ ("addl %2,%0\n\t" "addxl %3,%0\n\t" "addxl %4,%0\n\t" "clrl %1\n\t" "addxl %1,%0" : "=&d" (sum), "=d" (saddr) : "g" (daddr), "1" (saddr), "d" (len + proto), "0" (sum)); return sum; } /* * computes the checksum of the TCP/UDP pseudo-header * returns a 16-bit checksum, already complemented */ 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 */ static inline unsigned short ip_compute_csum(unsigned char * buff, int len) { return csum_fold (csum_partial(buff, len, 0)); } #define _HAVE_ARCH_IPV6_CSUM static __inline__ unsigned short int csum_ipv6_magic(struct in6_addr *saddr, struct in6_addr *daddr, __u32 len, unsigned short proto, unsigned int sum) { register unsigned long tmp; __asm__("addl %2@,%0\n\t" "movel %2@(4),%1\n\t" "addxl %1,%0\n\t" "movel %2@(8),%1\n\t" "addxl %1,%0\n\t" "movel %2@(12),%1\n\t" "addxl %1,%0\n\t" "movel %3@,%1\n\t" "addxl %1,%0\n\t" "movel %3@(4),%1\n\t" "addxl %1,%0\n\t" "movel %3@(8),%1\n\t" "addxl %1,%0\n\t" "movel %3@(12),%1\n\t" "addxl %1,%0\n\t" "addxl %4,%0\n\t" "clrl %1\n\t" "addxl %1,%0" : "=&d" (sum), "=&d" (tmp) : "a" (saddr), "a" (daddr), "d" (len + proto), "0" (sum)); return csum_fold(sum); } #endif /* _M68K_CHECKSUM_H */