1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __SPARC_CHECKSUM_H 3 #define __SPARC_CHECKSUM_H 4 5 /* checksum.h: IP/UDP/TCP checksum routines on the Sparc. 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 fs:src 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 42 unsigned int __csum_partial_copy_sparc_generic (const unsigned char *, unsigned char *); 43 44 static inline __wsum 45 csum_partial_copy_nocheck(const void *src, void *dst, int len) 46 { 47 register unsigned int ret asm("o0") = (unsigned int)src; 48 register char *d asm("o1") = dst; 49 register int l asm("g1") = len; 50 51 __asm__ __volatile__ ( 52 "call __csum_partial_copy_sparc_generic\n\t" 53 " mov -1, %%g7\n" 54 : "=&r" (ret), "=&r" (d), "=&r" (l) 55 : "0" (ret), "1" (d), "2" (l) 56 : "o2", "o3", "o4", "o5", "o7", 57 "g2", "g3", "g4", "g5", "g7", 58 "memory", "cc"); 59 return (__force __wsum)ret; 60 } 61 62 static inline __wsum 63 csum_and_copy_from_user(const void __user *src, void *dst, int len) 64 { 65 if (unlikely(!access_ok(src, len))) 66 return 0; 67 return csum_partial_copy_nocheck((__force void *)src, dst, len); 68 } 69 70 static inline __wsum 71 csum_and_copy_to_user(const void *src, void __user *dst, int len) 72 { 73 if (!access_ok(dst, len)) 74 return 0; 75 return csum_partial_copy_nocheck(src, (__force void *)dst, len); 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 */ 81 static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) 82 { 83 __sum16 sum; 84 85 /* Note: We must read %2 before we touch %0 for the first time, 86 * because GCC can legitimately use the same register for 87 * both operands. 88 */ 89 __asm__ __volatile__("sub\t%2, 4, %%g4\n\t" 90 "ld\t[%1 + 0x00], %0\n\t" 91 "ld\t[%1 + 0x04], %%g2\n\t" 92 "ld\t[%1 + 0x08], %%g3\n\t" 93 "addcc\t%%g2, %0, %0\n\t" 94 "addxcc\t%%g3, %0, %0\n\t" 95 "ld\t[%1 + 0x0c], %%g2\n\t" 96 "ld\t[%1 + 0x10], %%g3\n\t" 97 "addxcc\t%%g2, %0, %0\n\t" 98 "addx\t%0, %%g0, %0\n" 99 "1:\taddcc\t%%g3, %0, %0\n\t" 100 "add\t%1, 4, %1\n\t" 101 "addxcc\t%0, %%g0, %0\n\t" 102 "subcc\t%%g4, 1, %%g4\n\t" 103 "be,a\t2f\n\t" 104 "sll\t%0, 16, %%g2\n\t" 105 "b\t1b\n\t" 106 "ld\t[%1 + 0x10], %%g3\n" 107 "2:\taddcc\t%0, %%g2, %%g2\n\t" 108 "srl\t%%g2, 16, %0\n\t" 109 "addx\t%0, %%g0, %0\n\t" 110 "xnor\t%%g0, %0, %0" 111 : "=r" (sum), "=&r" (iph) 112 : "r" (ihl), "1" (iph) 113 : "g2", "g3", "g4", "cc", "memory"); 114 return sum; 115 } 116 117 /* Fold a partial checksum without adding pseudo headers. */ 118 static inline __sum16 csum_fold(__wsum sum) 119 { 120 unsigned int tmp; 121 122 __asm__ __volatile__("addcc\t%0, %1, %1\n\t" 123 "srl\t%1, 16, %1\n\t" 124 "addx\t%1, %%g0, %1\n\t" 125 "xnor\t%%g0, %1, %0" 126 : "=&r" (sum), "=r" (tmp) 127 : "0" (sum), "1" ((__force u32)sum<<16) 128 : "cc"); 129 return (__force __sum16)sum; 130 } 131 132 static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, 133 __u32 len, __u8 proto, 134 __wsum sum) 135 { 136 __asm__ __volatile__("addcc\t%1, %0, %0\n\t" 137 "addxcc\t%2, %0, %0\n\t" 138 "addxcc\t%3, %0, %0\n\t" 139 "addx\t%0, %%g0, %0\n\t" 140 : "=r" (sum), "=r" (saddr) 141 : "r" (daddr), "r" (proto + len), "0" (sum), 142 "1" (saddr) 143 : "cc"); 144 return sum; 145 } 146 147 /* 148 * computes the checksum of the TCP/UDP pseudo-header 149 * returns a 16-bit checksum, already complemented 150 */ 151 static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, 152 __u32 len, __u8 proto, 153 __wsum sum) 154 { 155 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum)); 156 } 157 158 #define _HAVE_ARCH_IPV6_CSUM 159 160 static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr, 161 const struct in6_addr *daddr, 162 __u32 len, __u8 proto, __wsum sum) 163 { 164 __asm__ __volatile__ ( 165 "addcc %3, %4, %%g4\n\t" 166 "addxcc %5, %%g4, %%g4\n\t" 167 "ld [%2 + 0x0c], %%g2\n\t" 168 "ld [%2 + 0x08], %%g3\n\t" 169 "addxcc %%g2, %%g4, %%g4\n\t" 170 "ld [%2 + 0x04], %%g2\n\t" 171 "addxcc %%g3, %%g4, %%g4\n\t" 172 "ld [%2 + 0x00], %%g3\n\t" 173 "addxcc %%g2, %%g4, %%g4\n\t" 174 "ld [%1 + 0x0c], %%g2\n\t" 175 "addxcc %%g3, %%g4, %%g4\n\t" 176 "ld [%1 + 0x08], %%g3\n\t" 177 "addxcc %%g2, %%g4, %%g4\n\t" 178 "ld [%1 + 0x04], %%g2\n\t" 179 "addxcc %%g3, %%g4, %%g4\n\t" 180 "ld [%1 + 0x00], %%g3\n\t" 181 "addxcc %%g2, %%g4, %%g4\n\t" 182 "addxcc %%g3, %%g4, %0\n\t" 183 "addx 0, %0, %0\n" 184 : "=&r" (sum) 185 : "r" (saddr), "r" (daddr), 186 "r"(htonl(len)), "r"(htonl(proto)), "r"(sum) 187 : "g2", "g3", "g4", "cc"); 188 189 return csum_fold(sum); 190 } 191 192 /* this routine is used for miscellaneous IP-like checksums, mainly in icmp.c */ 193 static inline __sum16 ip_compute_csum(const void *buff, int len) 194 { 195 return csum_fold(csum_partial(buff, len, 0)); 196 } 197 198 #define HAVE_ARCH_CSUM_ADD 199 static inline __wsum csum_add(__wsum csum, __wsum addend) 200 { 201 __asm__ __volatile__( 202 "addcc %0, %1, %0\n" 203 "addx %0, %%g0, %0" 204 : "=r" (csum) 205 : "r" (addend), "0" (csum)); 206 207 return csum; 208 } 209 210 #endif /* !(__SPARC_CHECKSUM_H) */ 211