1 /* SPDX-License-Identifier: GPL-2.0 */ 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 <linux/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 */ 33 __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 */ 41 __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len); 42 __wsum csum_and_copy_from_user(const void __user *src, void *dst, int len); 43 __wsum csum_and_copy_to_user(const void *src, void __user *dst, int len); 44 45 /* ihl is always 5 or greater, almost always is 5, and iph is word aligned 46 * the majority of the time. 47 */ 48 __sum16 ip_fast_csum(const void *iph, unsigned int ihl); 49 50 /* Fold a partial checksum without adding pseudo headers. */ 51 static inline __sum16 csum_fold(__wsum sum) 52 { 53 unsigned int tmp; 54 55 __asm__ __volatile__( 56 " addcc %0, %1, %1\n" 57 " srl %1, 16, %1\n" 58 " addc %1, %%g0, %1\n" 59 " xnor %%g0, %1, %0\n" 60 : "=&r" (sum), "=r" (tmp) 61 : "0" (sum), "1" ((__force u32)sum<<16) 62 : "cc"); 63 return (__force __sum16)sum; 64 } 65 66 static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, 67 __u32 len, __u8 proto, 68 __wsum sum) 69 { 70 __asm__ __volatile__( 71 " addcc %1, %0, %0\n" 72 " addccc %2, %0, %0\n" 73 " addccc %3, %0, %0\n" 74 " addc %0, %%g0, %0\n" 75 : "=r" (sum), "=r" (saddr) 76 : "r" (daddr), "r" (proto + len), "0" (sum), "1" (saddr) 77 : "cc"); 78 return sum; 79 } 80 81 /* 82 * computes the checksum of the TCP/UDP pseudo-header 83 * returns a 16-bit checksum, already complemented 84 */ 85 static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, 86 __u32 len, __u8 proto, 87 __wsum sum) 88 { 89 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum)); 90 } 91 92 #define _HAVE_ARCH_IPV6_CSUM 93 94 static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr, 95 const struct in6_addr *daddr, 96 __u32 len, __u8 proto, __wsum sum) 97 { 98 __asm__ __volatile__ ( 99 " addcc %3, %4, %%g7\n" 100 " addccc %5, %%g7, %%g7\n" 101 " lduw [%2 + 0x0c], %%g2\n" 102 " lduw [%2 + 0x08], %%g3\n" 103 " addccc %%g2, %%g7, %%g7\n" 104 " lduw [%2 + 0x04], %%g2\n" 105 " addccc %%g3, %%g7, %%g7\n" 106 " lduw [%2 + 0x00], %%g3\n" 107 " addccc %%g2, %%g7, %%g7\n" 108 " lduw [%1 + 0x0c], %%g2\n" 109 " addccc %%g3, %%g7, %%g7\n" 110 " lduw [%1 + 0x08], %%g3\n" 111 " addccc %%g2, %%g7, %%g7\n" 112 " lduw [%1 + 0x04], %%g2\n" 113 " addccc %%g3, %%g7, %%g7\n" 114 " lduw [%1 + 0x00], %%g3\n" 115 " addccc %%g2, %%g7, %%g7\n" 116 " addccc %%g3, %%g7, %0\n" 117 " addc 0, %0, %0\n" 118 : "=&r" (sum) 119 : "r" (saddr), "r" (daddr), "r"(htonl(len)), 120 "r"(htonl(proto)), "r"(sum) 121 : "g2", "g3", "g7", "cc"); 122 123 return csum_fold(sum); 124 } 125 126 /* this routine is used for miscellaneous IP-like checksums, mainly in icmp.c */ 127 static inline __sum16 ip_compute_csum(const void *buff, int len) 128 { 129 return csum_fold(csum_partial(buff, len, 0)); 130 } 131 132 #define HAVE_ARCH_CSUM_ADD 133 static inline __wsum csum_add(__wsum csum, __wsum addend) 134 { 135 __asm__ __volatile__( 136 "addcc %0, %1, %0\n" 137 "addx %0, %%g0, %0" 138 : "=r" (csum) 139 : "r" (addend), "0" (csum)); 140 141 return csum; 142 } 143 144 #endif /* !(__SPARC64_CHECKSUM_H) */ 145