1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _M68K_CHECKSUM_H 3 #define _M68K_CHECKSUM_H 4 5 #include <linux/in6.h> 6 7 #ifdef CONFIG_GENERIC_CSUM 8 #include <asm-generic/checksum.h> 9 #else 10 11 /* 12 * computes the checksum of a memory block at buff, length len, 13 * and adds in "sum" (32-bit) 14 * 15 * returns a 32-bit number suitable for feeding into itself 16 * or csum_tcpudp_magic 17 * 18 * this function must be called with even lengths, except 19 * for the last fragment, which may be odd 20 * 21 * it's best to have buff aligned on a 32-bit boundary 22 */ 23 __wsum csum_partial(const void *buff, int len, __wsum sum); 24 25 /* 26 * the same as csum_partial, but copies from src while it 27 * checksums 28 * 29 * here even more important to align src and dst on a 32-bit (or even 30 * better 64-bit) boundary 31 */ 32 33 #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER 34 extern __wsum csum_and_copy_from_user(const void __user *src, 35 void *dst, 36 int len, __wsum sum, 37 int *csum_err); 38 39 extern __wsum csum_partial_copy_nocheck(const void *src, 40 void *dst, int len, 41 __wsum sum); 42 43 /* 44 * This is a version of ip_fast_csum() optimized for IP headers, 45 * which always checksum on 4 octet boundaries. 46 */ 47 static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) 48 { 49 unsigned int sum = 0; 50 unsigned long tmp; 51 52 __asm__ ("subqw #1,%2\n" 53 "1:\t" 54 "movel %1@+,%3\n\t" 55 "addxl %3,%0\n\t" 56 "dbra %2,1b\n\t" 57 "movel %0,%3\n\t" 58 "swap %3\n\t" 59 "addxw %3,%0\n\t" 60 "clrw %3\n\t" 61 "addxw %3,%0\n\t" 62 : "=d" (sum), "=&a" (iph), "=&d" (ihl), "=&d" (tmp) 63 : "0" (sum), "1" (iph), "2" (ihl) 64 : "memory"); 65 return (__force __sum16)~sum; 66 } 67 68 static inline __sum16 csum_fold(__wsum sum) 69 { 70 unsigned int tmp = (__force u32)sum; 71 72 __asm__("swap %1\n\t" 73 "addw %1, %0\n\t" 74 "clrw %1\n\t" 75 "addxw %1, %0" 76 : "=&d" (sum), "=&d" (tmp) 77 : "0" (sum), "1" (tmp)); 78 79 return (__force __sum16)~sum; 80 } 81 82 static inline __wsum 83 csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len, 84 unsigned short proto, __wsum sum) 85 { 86 __asm__ ("addl %2,%0\n\t" 87 "addxl %3,%0\n\t" 88 "addxl %4,%0\n\t" 89 "clrl %1\n\t" 90 "addxl %1,%0" 91 : "=&d" (sum), "=d" (saddr) 92 : "g" (daddr), "1" (saddr), "d" (len + proto), 93 "0" (sum)); 94 return sum; 95 } 96 97 98 /* 99 * computes the checksum of the TCP/UDP pseudo-header 100 * returns a 16-bit checksum, already complemented 101 */ 102 static inline __sum16 103 csum_tcpudp_magic(__be32 saddr, __be32 daddr, unsigned short len, 104 unsigned short proto, __wsum sum) 105 { 106 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum)); 107 } 108 109 /* 110 * this routine is used for miscellaneous IP-like checksums, mainly 111 * in icmp.c 112 */ 113 114 static inline __sum16 ip_compute_csum(const void *buff, int len) 115 { 116 return csum_fold (csum_partial(buff, len, 0)); 117 } 118 119 #define _HAVE_ARCH_IPV6_CSUM 120 static __inline__ __sum16 121 csum_ipv6_magic(const struct in6_addr *saddr, const struct in6_addr *daddr, 122 __u32 len, __u8 proto, __wsum sum) 123 { 124 register unsigned long tmp; 125 __asm__("addl %2@,%0\n\t" 126 "movel %2@(4),%1\n\t" 127 "addxl %1,%0\n\t" 128 "movel %2@(8),%1\n\t" 129 "addxl %1,%0\n\t" 130 "movel %2@(12),%1\n\t" 131 "addxl %1,%0\n\t" 132 "movel %3@,%1\n\t" 133 "addxl %1,%0\n\t" 134 "movel %3@(4),%1\n\t" 135 "addxl %1,%0\n\t" 136 "movel %3@(8),%1\n\t" 137 "addxl %1,%0\n\t" 138 "movel %3@(12),%1\n\t" 139 "addxl %1,%0\n\t" 140 "addxl %4,%0\n\t" 141 "clrl %1\n\t" 142 "addxl %1,%0" 143 : "=&d" (sum), "=&d" (tmp) 144 : "a" (saddr), "a" (daddr), "d" (len + proto), 145 "0" (sum)); 146 147 return csum_fold(sum); 148 } 149 150 #endif /* CONFIG_GENERIC_CSUM */ 151 #endif /* _M68K_CHECKSUM_H */ 152