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 */ 18 extern __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 */ 26 extern __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 */ 32 extern __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 */ 41 static 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", "memory"); 69 70 return (__force __sum16)sum; 71 } 72 73 /* 74 * Fold a partial checksum 75 */ 76 static 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 87 static 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 */ 106 static 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 */ 118 static 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 125 static __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", "memory"); 186 return csum_fold(sum); 187 } 188 189 /* 190 * Copy and checksum to user 191 */ 192 #define HAVE_CSUM_COPY_USER 193 static __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 210 211