1#ifndef _PARISC_CHECKSUM_H 2#define _PARISC_CHECKSUM_H 3 4#include <linux/in6.h> 5 6/* 7 * computes the checksum of a memory block at buff, length len, 8 * and adds in "sum" (32-bit) 9 * 10 * returns a 32-bit number suitable for feeding into itself 11 * or csum_tcpudp_magic 12 * 13 * this function must be called with even lengths, except 14 * for the last fragment, which may be odd 15 * 16 * it's best to have buff aligned on a 32-bit boundary 17 */ 18extern __wsum csum_partial(const void *, int, __wsum); 19 20/* 21 * The same as csum_partial, but copies from src while it checksums. 22 * 23 * Here even more important to align src and dst on a 32-bit (or even 24 * better 64-bit) boundary 25 */ 26extern __wsum csum_partial_copy_nocheck(const void *, void *, int, __wsum); 27 28/* 29 * this is a new version of the above that records errors it finds in *errp, 30 * but continues and zeros the rest of the buffer. 31 */ 32extern __wsum csum_partial_copy_from_user(const void __user *src, 33 void *dst, int len, __wsum sum, int *errp); 34 35/* 36 * Optimized for IP headers, which always checksum on 4 octet boundaries. 37 * 38 * Written by Randolph Chung <tausq@debian.org>, and then mucked with by 39 * LaMont Jones <lamont@debian.org> 40 */ 41static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) 42{ 43 unsigned int sum; 44 45 __asm__ __volatile__ ( 46" ldws,ma 4(%1), %0\n" 47" addib,<= -4, %2, 2f\n" 48"\n" 49" ldws 4(%1), %%r20\n" 50" ldws 8(%1), %%r21\n" 51" add %0, %%r20, %0\n" 52" ldws,ma 12(%1), %%r19\n" 53" addc %0, %%r21, %0\n" 54" addc %0, %%r19, %0\n" 55"1: ldws,ma 4(%1), %%r19\n" 56" addib,< 0, %2, 1b\n" 57" addc %0, %%r19, %0\n" 58"\n" 59" extru %0, 31, 16, %%r20\n" 60" extru %0, 15, 16, %%r21\n" 61" addc %%r20, %%r21, %0\n" 62" extru %0, 15, 16, %%r21\n" 63" add %0, %%r21, %0\n" 64" subi -1, %0, %0\n" 65"2:\n" 66 : "=r" (sum), "=r" (iph), "=r" (ihl) 67 : "1" (iph), "2" (ihl) 68 : "r19", "r20", "r21" ); 69 70 return (__force __sum16)sum; 71} 72 73/* 74 * Fold a partial checksum 75 */ 76static inline __sum16 csum_fold(__wsum csum) 77{ 78 u32 sum = (__force u32)csum; 79 /* add the swapped two 16-bit halves of sum, 80 a possible carry from adding the two 16-bit halves, 81 will carry from the lower half into the upper half, 82 giving us the correct sum in the upper half. */ 83 sum += (sum << 16) + (sum >> 16); 84 return (__force __sum16)(~sum >> 16); 85} 86 87static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, 88 unsigned short len, 89 unsigned short proto, 90 __wsum sum) 91{ 92 __asm__( 93 " add %1, %0, %0\n" 94 " addc %2, %0, %0\n" 95 " addc %3, %0, %0\n" 96 " addc %%r0, %0, %0\n" 97 : "=r" (sum) 98 : "r" (daddr), "r"(saddr), "r"(proto+len), "0"(sum)); 99 return sum; 100} 101 102/* 103 * computes the checksum of the TCP/UDP pseudo-header 104 * returns a 16-bit checksum, already complemented 105 */ 106static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, 107 unsigned short len, 108 unsigned short proto, 109 __wsum sum) 110{ 111 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum)); 112} 113 114/* 115 * this routine is used for miscellaneous IP-like checksums, mainly 116 * in icmp.c 117 */ 118static inline __sum16 ip_compute_csum(const void *buf, int len) 119{ 120 return csum_fold (csum_partial(buf, len, 0)); 121} 122 123 124#define _HAVE_ARCH_IPV6_CSUM 125static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr, 126 const struct in6_addr *daddr, 127 __u32 len, unsigned short proto, 128 __wsum sum) 129{ 130 __asm__ __volatile__ ( 131 132#if BITS_PER_LONG > 32 133 134 /* 135 ** We can execute two loads and two adds per cycle on PA 8000. 136 ** But add insn's get serialized waiting for the carry bit. 137 ** Try to keep 4 registers with "live" values ahead of the ALU. 138 */ 139 140" ldd,ma 8(%1), %%r19\n" /* get 1st saddr word */ 141" ldd,ma 8(%2), %%r20\n" /* get 1st daddr word */ 142" add %8, %3, %3\n"/* add 16-bit proto + len */ 143" add %%r19, %0, %0\n" 144" ldd,ma 8(%1), %%r21\n" /* 2cd saddr */ 145" ldd,ma 8(%2), %%r22\n" /* 2cd daddr */ 146" add,dc %%r20, %0, %0\n" 147" add,dc %%r21, %0, %0\n" 148" add,dc %%r22, %0, %0\n" 149" add,dc %3, %0, %0\n" /* fold in proto+len | carry bit */ 150" extrd,u %0, 31, 32, %%r19\n" /* copy upper half down */ 151" depdi 0, 31, 32, %0\n" /* clear upper half */ 152" add %%r19, %0, %0\n" /* fold into 32-bits */ 153" addc 0, %0, %0\n" /* add carry */ 154 155#else 156 157 /* 158 ** For PA 1.x, the insn order doesn't matter as much. 159 ** Insn stream is serialized on the carry bit here too. 160 ** result from the previous operation (eg r0 + x) 161 */ 162 163" ldw,ma 4(%1), %%r19\n" /* get 1st saddr word */ 164" ldw,ma 4(%2), %%r20\n" /* get 1st daddr word */ 165" add %8, %3, %3\n" /* add 16-bit proto + len */ 166" add %%r19, %0, %0\n" 167" ldw,ma 4(%1), %%r21\n" /* 2cd saddr */ 168" addc %%r20, %0, %0\n" 169" ldw,ma 4(%2), %%r22\n" /* 2cd daddr */ 170" addc %%r21, %0, %0\n" 171" ldw,ma 4(%1), %%r19\n" /* 3rd saddr */ 172" addc %%r22, %0, %0\n" 173" ldw,ma 4(%2), %%r20\n" /* 3rd daddr */ 174" addc %%r19, %0, %0\n" 175" ldw,ma 4(%1), %%r21\n" /* 4th saddr */ 176" addc %%r20, %0, %0\n" 177" ldw,ma 4(%2), %%r22\n" /* 4th daddr */ 178" addc %%r21, %0, %0\n" 179" addc %%r22, %0, %0\n" 180" addc %3, %0, %0\n" /* fold in proto+len, catch carry */ 181 182#endif 183 : "=r" (sum), "=r" (saddr), "=r" (daddr), "=r" (len) 184 : "0" (sum), "1" (saddr), "2" (daddr), "3" (len), "r" (proto) 185 : "r19", "r20", "r21", "r22"); 186 return csum_fold(sum); 187} 188 189/* 190 * Copy and checksum to user 191 */ 192#define HAVE_CSUM_COPY_USER 193static __inline__ __wsum csum_and_copy_to_user(const void *src, 194 void __user *dst, 195 int len, __wsum sum, 196 int *err_ptr) 197{ 198 /* code stolen from include/asm-mips64 */ 199 sum = csum_partial(src, len, sum); 200 201 if (copy_to_user(dst, src, len)) { 202 *err_ptr = -EFAULT; 203 return (__force __wsum)-1; 204 } 205 206 return sum; 207} 208 209#endif 210