1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _PARISC_CHECKSUM_H 3 #define _PARISC_CHECKSUM_H 4 5 #include <linux/in6.h> 6 7 /* 8 * computes the checksum of a memory block at buff, length len, 9 * and adds in "sum" (32-bit) 10 * 11 * returns a 32-bit number suitable for feeding into itself 12 * or csum_tcpudp_magic 13 * 14 * this function must be called with even lengths, except 15 * for the last fragment, which may be odd 16 * 17 * it's best to have buff aligned on a 32-bit boundary 18 */ 19 extern __wsum csum_partial(const void *, int, __wsum); 20 21 /* 22 * The same as csum_partial, but copies from src while it checksums. 23 * 24 * Here even more important to align src and dst on a 32-bit (or even 25 * better 64-bit) boundary 26 */ 27 extern __wsum csum_partial_copy_nocheck(const void *, void *, int, __wsum); 28 29 /* 30 * Optimized for IP headers, which always checksum on 4 octet boundaries. 31 * 32 * Written by Randolph Chung <tausq@debian.org>, and then mucked with by 33 * LaMont Jones <lamont@debian.org> 34 */ 35 static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) 36 { 37 unsigned int sum; 38 unsigned long t0, t1, t2; 39 40 __asm__ __volatile__ ( 41 " ldws,ma 4(%1), %0\n" 42 " addib,<= -4, %2, 2f\n" 43 "\n" 44 " ldws 4(%1), %4\n" 45 " ldws 8(%1), %5\n" 46 " add %0, %4, %0\n" 47 " ldws,ma 12(%1), %3\n" 48 " addc %0, %5, %0\n" 49 " addc %0, %3, %0\n" 50 "1: ldws,ma 4(%1), %3\n" 51 " addib,< 0, %2, 1b\n" 52 " addc %0, %3, %0\n" 53 "\n" 54 " extru %0, 31, 16, %4\n" 55 " extru %0, 15, 16, %5\n" 56 " addc %4, %5, %0\n" 57 " extru %0, 15, 16, %5\n" 58 " add %0, %5, %0\n" 59 " subi -1, %0, %0\n" 60 "2:\n" 61 : "=r" (sum), "=r" (iph), "=r" (ihl), "=r" (t0), "=r" (t1), "=r" (t2) 62 : "1" (iph), "2" (ihl) 63 : "memory"); 64 65 return (__force __sum16)sum; 66 } 67 68 /* 69 * Fold a partial checksum 70 */ 71 static inline __sum16 csum_fold(__wsum csum) 72 { 73 u32 sum = (__force u32)csum; 74 /* add the swapped two 16-bit halves of sum, 75 a possible carry from adding the two 16-bit halves, 76 will carry from the lower half into the upper half, 77 giving us the correct sum in the upper half. */ 78 sum += (sum << 16) + (sum >> 16); 79 return (__force __sum16)(~sum >> 16); 80 } 81 82 static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, 83 __u32 len, __u8 proto, 84 __wsum sum) 85 { 86 __asm__( 87 " add %1, %0, %0\n" 88 " addc %2, %0, %0\n" 89 " addc %3, %0, %0\n" 90 " addc %%r0, %0, %0\n" 91 : "=r" (sum) 92 : "r" (daddr), "r"(saddr), "r"(proto+len), "0"(sum)); 93 return sum; 94 } 95 96 /* 97 * computes the checksum of the TCP/UDP pseudo-header 98 * returns a 16-bit checksum, already complemented 99 */ 100 static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, 101 __u32 len, __u8 proto, 102 __wsum sum) 103 { 104 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum)); 105 } 106 107 /* 108 * this routine is used for miscellaneous IP-like checksums, mainly 109 * in icmp.c 110 */ 111 static inline __sum16 ip_compute_csum(const void *buf, int len) 112 { 113 return csum_fold (csum_partial(buf, len, 0)); 114 } 115 116 117 #define _HAVE_ARCH_IPV6_CSUM 118 static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr, 119 const struct in6_addr *daddr, 120 __u32 len, __u8 proto, 121 __wsum sum) 122 { 123 unsigned long t0, t1, t2, t3; 124 125 len += proto; /* add 16-bit proto + len */ 126 127 __asm__ __volatile__ ( 128 129 #if BITS_PER_LONG > 32 130 131 /* 132 ** We can execute two loads and two adds per cycle on PA 8000. 133 ** But add insn's get serialized waiting for the carry bit. 134 ** Try to keep 4 registers with "live" values ahead of the ALU. 135 */ 136 137 " ldd,ma 8(%1), %4\n" /* get 1st saddr word */ 138 " ldd,ma 8(%2), %5\n" /* get 1st daddr word */ 139 " add %4, %0, %0\n" 140 " ldd,ma 8(%1), %6\n" /* 2nd saddr */ 141 " ldd,ma 8(%2), %7\n" /* 2nd daddr */ 142 " add,dc %5, %0, %0\n" 143 " add,dc %6, %0, %0\n" 144 " add,dc %7, %0, %0\n" 145 " add,dc %3, %0, %0\n" /* fold in proto+len | carry bit */ 146 " extrd,u %0, 31, 32, %4\n"/* copy upper half down */ 147 " depdi 0, 31, 32, %0\n"/* clear upper half */ 148 " add %4, %0, %0\n" /* fold into 32-bits */ 149 " addc 0, %0, %0\n" /* add carry */ 150 151 #else 152 153 /* 154 ** For PA 1.x, the insn order doesn't matter as much. 155 ** Insn stream is serialized on the carry bit here too. 156 ** result from the previous operation (eg r0 + x) 157 */ 158 " ldw,ma 4(%1), %4\n" /* get 1st saddr word */ 159 " ldw,ma 4(%2), %5\n" /* get 1st daddr word */ 160 " add %4, %0, %0\n" 161 " ldw,ma 4(%1), %6\n" /* 2nd saddr */ 162 " addc %5, %0, %0\n" 163 " ldw,ma 4(%2), %7\n" /* 2nd daddr */ 164 " addc %6, %0, %0\n" 165 " ldw,ma 4(%1), %4\n" /* 3rd saddr */ 166 " addc %7, %0, %0\n" 167 " ldw,ma 4(%2), %5\n" /* 3rd daddr */ 168 " addc %4, %0, %0\n" 169 " ldw,ma 4(%1), %6\n" /* 4th saddr */ 170 " addc %5, %0, %0\n" 171 " ldw,ma 4(%2), %7\n" /* 4th daddr */ 172 " addc %6, %0, %0\n" 173 " addc %7, %0, %0\n" 174 " addc %3, %0, %0\n" /* fold in proto+len, catch carry */ 175 176 #endif 177 : "=r" (sum), "=r" (saddr), "=r" (daddr), "=r" (len), 178 "=r" (t0), "=r" (t1), "=r" (t2), "=r" (t3) 179 : "0" (sum), "1" (saddr), "2" (daddr), "3" (len) 180 : "memory"); 181 return csum_fold(sum); 182 } 183 184 /* 185 * Copy and checksum to user 186 */ 187 #define HAVE_CSUM_COPY_USER 188 static __inline__ __wsum csum_and_copy_to_user(const void *src, 189 void __user *dst, 190 int len, __wsum sum, 191 int *err_ptr) 192 { 193 /* code stolen from include/asm-mips64 */ 194 sum = csum_partial(src, len, sum); 195 196 if (copy_to_user(dst, src, len)) { 197 *err_ptr = -EFAULT; 198 return (__force __wsum)-1; 199 } 200 201 return sum; 202 } 203 204 #endif 205 206