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 __u32 len, __u8 proto, 89 __wsum sum) 90 { 91 __asm__( 92 " add %1, %0, %0\n" 93 " addc %2, %0, %0\n" 94 " addc %3, %0, %0\n" 95 " addc %%r0, %0, %0\n" 96 : "=r" (sum) 97 : "r" (daddr), "r"(saddr), "r"(proto+len), "0"(sum)); 98 return sum; 99 } 100 101 /* 102 * computes the checksum of the TCP/UDP pseudo-header 103 * returns a 16-bit checksum, already complemented 104 */ 105 static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, 106 __u32 len, __u8 proto, 107 __wsum sum) 108 { 109 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum)); 110 } 111 112 /* 113 * this routine is used for miscellaneous IP-like checksums, mainly 114 * in icmp.c 115 */ 116 static inline __sum16 ip_compute_csum(const void *buf, int len) 117 { 118 return csum_fold (csum_partial(buf, len, 0)); 119 } 120 121 122 #define _HAVE_ARCH_IPV6_CSUM 123 static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr, 124 const struct in6_addr *daddr, 125 __u32 len, __u8 proto, 126 __wsum sum) 127 { 128 __asm__ __volatile__ ( 129 130 #if BITS_PER_LONG > 32 131 132 /* 133 ** We can execute two loads and two adds per cycle on PA 8000. 134 ** But add insn's get serialized waiting for the carry bit. 135 ** Try to keep 4 registers with "live" values ahead of the ALU. 136 */ 137 138 " ldd,ma 8(%1), %%r19\n" /* get 1st saddr word */ 139 " ldd,ma 8(%2), %%r20\n" /* get 1st daddr word */ 140 " add %8, %3, %3\n"/* add 16-bit proto + len */ 141 " add %%r19, %0, %0\n" 142 " ldd,ma 8(%1), %%r21\n" /* 2cd saddr */ 143 " ldd,ma 8(%2), %%r22\n" /* 2cd daddr */ 144 " add,dc %%r20, %0, %0\n" 145 " add,dc %%r21, %0, %0\n" 146 " add,dc %%r22, %0, %0\n" 147 " add,dc %3, %0, %0\n" /* fold in proto+len | carry bit */ 148 " extrd,u %0, 31, 32, %%r19\n" /* copy upper half down */ 149 " depdi 0, 31, 32, %0\n" /* clear upper half */ 150 " add %%r19, %0, %0\n" /* fold into 32-bits */ 151 " addc 0, %0, %0\n" /* add carry */ 152 153 #else 154 155 /* 156 ** For PA 1.x, the insn order doesn't matter as much. 157 ** Insn stream is serialized on the carry bit here too. 158 ** result from the previous operation (eg r0 + x) 159 */ 160 161 " ldw,ma 4(%1), %%r19\n" /* get 1st saddr word */ 162 " ldw,ma 4(%2), %%r20\n" /* get 1st daddr word */ 163 " add %8, %3, %3\n" /* add 16-bit proto + len */ 164 " add %%r19, %0, %0\n" 165 " ldw,ma 4(%1), %%r21\n" /* 2cd saddr */ 166 " addc %%r20, %0, %0\n" 167 " ldw,ma 4(%2), %%r22\n" /* 2cd daddr */ 168 " addc %%r21, %0, %0\n" 169 " ldw,ma 4(%1), %%r19\n" /* 3rd saddr */ 170 " addc %%r22, %0, %0\n" 171 " ldw,ma 4(%2), %%r20\n" /* 3rd daddr */ 172 " addc %%r19, %0, %0\n" 173 " ldw,ma 4(%1), %%r21\n" /* 4th saddr */ 174 " addc %%r20, %0, %0\n" 175 " ldw,ma 4(%2), %%r22\n" /* 4th daddr */ 176 " addc %%r21, %0, %0\n" 177 " addc %%r22, %0, %0\n" 178 " addc %3, %0, %0\n" /* fold in proto+len, catch carry */ 179 180 #endif 181 : "=r" (sum), "=r" (saddr), "=r" (daddr), "=r" (len) 182 : "0" (sum), "1" (saddr), "2" (daddr), "3" (len), "r" (proto) 183 : "r19", "r20", "r21", "r22", "memory"); 184 return csum_fold(sum); 185 } 186 187 /* 188 * Copy and checksum to user 189 */ 190 #define HAVE_CSUM_COPY_USER 191 static __inline__ __wsum csum_and_copy_to_user(const void *src, 192 void __user *dst, 193 int len, __wsum sum, 194 int *err_ptr) 195 { 196 /* code stolen from include/asm-mips64 */ 197 sum = csum_partial(src, len, sum); 198 199 if (copy_to_user(dst, src, len)) { 200 *err_ptr = -EFAULT; 201 return (__force __wsum)-1; 202 } 203 204 return sum; 205 } 206 207 #endif 208 209