checksum.h (3497B)
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#define _HAVE_ARCH_CSUM_AND_COPY 35extern __wsum csum_and_copy_from_user(const void __user *src, 36 void *dst, 37 int len); 38 39extern __wsum csum_partial_copy_nocheck(const void *src, 40 void *dst, int len); 41 42/* 43 * This is a version of ip_fast_csum() optimized for IP headers, 44 * which always checksum on 4 octet boundaries. 45 */ 46static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) 47{ 48 unsigned int sum = 0; 49 unsigned long tmp; 50 51 __asm__ ("subqw #1,%2\n" 52 "1:\t" 53 "movel %1@+,%3\n\t" 54 "addxl %3,%0\n\t" 55 "dbra %2,1b\n\t" 56 "movel %0,%3\n\t" 57 "swap %3\n\t" 58 "addxw %3,%0\n\t" 59 "clrw %3\n\t" 60 "addxw %3,%0\n\t" 61 : "=d" (sum), "=&a" (iph), "=&d" (ihl), "=&d" (tmp) 62 : "0" (sum), "1" (iph), "2" (ihl) 63 : "memory"); 64 return (__force __sum16)~sum; 65} 66 67static inline __sum16 csum_fold(__wsum sum) 68{ 69 unsigned int tmp = (__force u32)sum; 70 71 __asm__("swap %1\n\t" 72 "addw %1, %0\n\t" 73 "clrw %1\n\t" 74 "addxw %1, %0" 75 : "=&d" (sum), "=&d" (tmp) 76 : "0" (sum), "1" (tmp)); 77 78 return (__force __sum16)~sum; 79} 80 81static inline __wsum 82csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len, 83 unsigned short proto, __wsum sum) 84{ 85 __asm__ ("addl %2,%0\n\t" 86 "addxl %3,%0\n\t" 87 "addxl %4,%0\n\t" 88 "clrl %1\n\t" 89 "addxl %1,%0" 90 : "=&d" (sum), "=d" (saddr) 91 : "g" (daddr), "1" (saddr), "d" (len + proto), 92 "0" (sum)); 93 return sum; 94} 95 96 97/* 98 * computes the checksum of the TCP/UDP pseudo-header 99 * returns a 16-bit checksum, already complemented 100 */ 101static inline __sum16 102csum_tcpudp_magic(__be32 saddr, __be32 daddr, unsigned short len, 103 unsigned short proto, __wsum sum) 104{ 105 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum)); 106} 107 108/* 109 * this routine is used for miscellaneous IP-like checksums, mainly 110 * in icmp.c 111 */ 112 113static inline __sum16 ip_compute_csum(const void *buff, int len) 114{ 115 return csum_fold (csum_partial(buff, len, 0)); 116} 117 118#define _HAVE_ARCH_IPV6_CSUM 119static __inline__ __sum16 120csum_ipv6_magic(const struct in6_addr *saddr, const struct in6_addr *daddr, 121 __u32 len, __u8 proto, __wsum sum) 122{ 123 register unsigned long tmp; 124 __asm__("addl %2@,%0\n\t" 125 "movel %2@(4),%1\n\t" 126 "addxl %1,%0\n\t" 127 "movel %2@(8),%1\n\t" 128 "addxl %1,%0\n\t" 129 "movel %2@(12),%1\n\t" 130 "addxl %1,%0\n\t" 131 "movel %3@,%1\n\t" 132 "addxl %1,%0\n\t" 133 "movel %3@(4),%1\n\t" 134 "addxl %1,%0\n\t" 135 "movel %3@(8),%1\n\t" 136 "addxl %1,%0\n\t" 137 "movel %3@(12),%1\n\t" 138 "addxl %1,%0\n\t" 139 "addxl %4,%0\n\t" 140 "clrl %1\n\t" 141 "addxl %1,%0" 142 : "=&d" (sum), "=&d" (tmp) 143 : "a" (saddr), "a" (daddr), "d" (len + proto), 144 "0" (sum)); 145 146 return csum_fold(sum); 147} 148 149#endif /* CONFIG_GENERIC_CSUM */ 150#endif /* _M68K_CHECKSUM_H */