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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 | #ifndef _M68K_CHECKSUM_H #define _M68K_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)) /* * 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; __asm__ ("subqw #1,%2\n" "1:\t" "movel %1@+,%/d0\n\t" "addxl %/d0,%0\n\t" "dbra %2,1b\n\t" "movel %0,%/d0\n\t" "swap %/d0\n\t" "addxw %/d0,%0\n\t" "clrw %/d0\n\t" "addxw %/d0,%0\n\t" : "=d" (sum), "=a" (iph), "=d" (ihl) : "0" (sum), "1" (iph), "2" (ihl) : "d0"); 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" (sum)); 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__ ("addl %1,%0\n\t" "addxl %4,%0\n\t" "addxl %5,%0\n\t" "clrl %1\n\t" "addxl %1,%0" : "=&d" (sum), "=&d" (saddr) : "0" (daddr), "1" (saddr), "d" (len + proto), "d"(sum)); 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 */ 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 */ |