1/* $Id: checksum.h,v 1.1.1.1 2007/08/03 18:53:36 Exp $ */ 2#ifndef __SPARC64_CHECKSUM_H 3#define __SPARC64_CHECKSUM_H 4 5/* checksum.h: IP/UDP/TCP checksum routines on the V9. 6 * 7 * Copyright(C) 1995 Linus Torvalds 8 * Copyright(C) 1995 Miguel de Icaza 9 * Copyright(C) 1996 David S. Miller 10 * Copyright(C) 1996 Eddie C. Dost 11 * Copyright(C) 1997 Jakub Jelinek 12 * 13 * derived from: 14 * Alpha checksum c-code 15 * ix86 inline assembly 16 * RFC1071 Computing the Internet Checksum 17 */ 18 19#include <linux/in6.h> 20#include <asm/uaccess.h> 21 22/* computes the checksum of a memory block at buff, length len, 23 * and adds in "sum" (32-bit) 24 * 25 * returns a 32-bit number suitable for feeding into itself 26 * or csum_tcpudp_magic 27 * 28 * this function must be called with even lengths, except 29 * for the last fragment, which may be odd 30 * 31 * it's best to have buff aligned on a 32-bit boundary 32 */ 33extern __wsum csum_partial(const void * buff, int len, __wsum sum); 34 35/* the same as csum_partial, but copies from user space while it 36 * checksums 37 * 38 * here even more important to align src and dst on a 32-bit (or even 39 * better 64-bit) boundary 40 */ 41extern __wsum csum_partial_copy_nocheck(const void *src, void *dst, 42 int len, __wsum sum); 43 44extern long __csum_partial_copy_from_user(const void __user *src, 45 void *dst, int len, 46 __wsum sum); 47 48static inline __wsum 49csum_partial_copy_from_user(const void __user *src, 50 void *dst, int len, 51 __wsum sum, int *err) 52{ 53 long ret = __csum_partial_copy_from_user(src, dst, len, sum); 54 if (ret < 0) 55 *err = -EFAULT; 56 return (__force __wsum) ret; 57} 58 59/* 60 * Copy and checksum to user 61 */ 62#define HAVE_CSUM_COPY_USER 63extern long __csum_partial_copy_to_user(const void *src, 64 void __user *dst, int len, 65 __wsum sum); 66 67static inline __wsum 68csum_and_copy_to_user(const void *src, 69 void __user *dst, int len, 70 __wsum sum, int *err) 71{ 72 long ret = __csum_partial_copy_to_user(src, dst, len, sum); 73 if (ret < 0) 74 *err = -EFAULT; 75 return (__force __wsum) ret; 76} 77 78/* ihl is always 5 or greater, almost always is 5, and iph is word aligned 79 * the majority of the time. 80 */ 81extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl); 82 83/* Fold a partial checksum without adding pseudo headers. */ 84static inline __sum16 csum_fold(__wsum sum) 85{ 86 unsigned int tmp; 87 88 __asm__ __volatile__( 89" addcc %0, %1, %1\n" 90" srl %1, 16, %1\n" 91" addc %1, %%g0, %1\n" 92" xnor %%g0, %1, %0\n" 93 : "=&r" (sum), "=r" (tmp) 94 : "0" (sum), "1" ((__force u32)sum<<16) 95 : "cc"); 96 return (__force __sum16)sum; 97} 98 99static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, 100 unsigned int len, 101 unsigned short proto, 102 __wsum sum) 103{ 104 __asm__ __volatile__( 105" addcc %1, %0, %0\n" 106" addccc %2, %0, %0\n" 107" addccc %3, %0, %0\n" 108" addc %0, %%g0, %0\n" 109 : "=r" (sum), "=r" (saddr) 110 : "r" (daddr), "r" (proto + len), "0" (sum), "1" (saddr) 111 : "cc"); 112 return sum; 113} 114 115/* 116 * computes the checksum of the TCP/UDP pseudo-header 117 * returns a 16-bit checksum, already complemented 118 */ 119static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, 120 unsigned short len, 121 unsigned short proto, 122 __wsum sum) 123{ 124 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum)); 125} 126 127#define _HAVE_ARCH_IPV6_CSUM 128 129static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr, 130 const struct in6_addr *daddr, 131 __u32 len, unsigned short proto, 132 __wsum sum) 133{ 134 __asm__ __volatile__ ( 135" addcc %3, %4, %%g7\n" 136" addccc %5, %%g7, %%g7\n" 137" lduw [%2 + 0x0c], %%g2\n" 138" lduw [%2 + 0x08], %%g3\n" 139" addccc %%g2, %%g7, %%g7\n" 140" lduw [%2 + 0x04], %%g2\n" 141" addccc %%g3, %%g7, %%g7\n" 142" lduw [%2 + 0x00], %%g3\n" 143" addccc %%g2, %%g7, %%g7\n" 144" lduw [%1 + 0x0c], %%g2\n" 145" addccc %%g3, %%g7, %%g7\n" 146" lduw [%1 + 0x08], %%g3\n" 147" addccc %%g2, %%g7, %%g7\n" 148" lduw [%1 + 0x04], %%g2\n" 149" addccc %%g3, %%g7, %%g7\n" 150" lduw [%1 + 0x00], %%g3\n" 151" addccc %%g2, %%g7, %%g7\n" 152" addccc %%g3, %%g7, %0\n" 153" addc 0, %0, %0\n" 154 : "=&r" (sum) 155 : "r" (saddr), "r" (daddr), "r"(htonl(len)), 156 "r"(htonl(proto)), "r"(sum) 157 : "g2", "g3", "g7", "cc"); 158 159 return csum_fold(sum); 160} 161 162/* this routine is used for miscellaneous IP-like checksums, mainly in icmp.c */ 163static inline __sum16 ip_compute_csum(const void *buff, int len) 164{ 165 return csum_fold(csum_partial(buff, len, 0)); 166} 167 168#endif /* !(__SPARC64_CHECKSUM_H) */ 169