1/* MN10300 Optimised checksumming code 2 * 3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. 4 * Written by David Howells (dhowells@redhat.com) 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public Licence 8 * as published by the Free Software Foundation; either version 9 * 2 of the Licence, or (at your option) any later version. 10 */ 11#ifndef _ASM_CHECKSUM_H 12#define _ASM_CHECKSUM_H 13 14extern __wsum csum_partial(const void *buff, int len, __wsum sum); 15extern __wsum csum_partial_copy_nocheck(const void *src, void *dst, 16 int len, __wsum sum); 17extern __wsum csum_partial_copy_from_user(const void *src, void *dst, 18 int len, __wsum sum, 19 int *err_ptr); 20extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl); 21extern __wsum csum_partial(const void *buff, int len, __wsum sum); 22extern __sum16 ip_compute_csum(const void *buff, int len); 23 24#define csum_partial_copy_fromuser csum_partial_copy 25extern __wsum csum_partial_copy(const void *src, void *dst, int len, 26 __wsum sum); 27 28static inline __sum16 csum_fold(__wsum sum) 29{ 30 asm( 31 " add %1,%0 \n" 32 " addc 0xffff,%0 \n" 33 : "=r" (sum) 34 : "r" (sum << 16), "0" (sum & 0xffff0000) 35 : "cc" 36 ); 37 return (~sum) >> 16; 38} 39 40static inline __wsum csum_tcpudp_nofold(unsigned long saddr, 41 unsigned long daddr, 42 unsigned short len, 43 unsigned short proto, 44 __wsum sum) 45{ 46 __wsum tmp; 47 48 tmp = (__wsum) ntohs(len) << 16; 49 tmp += (__wsum) proto << 8; 50 51 asm( 52 " add %1,%0 \n" 53 " addc %2,%0 \n" 54 " addc %3,%0 \n" 55 " addc 0,%0 \n" 56 : "=r" (sum) 57 : "r" (daddr), "r"(saddr), "r"(tmp), "0"(sum) 58 : "cc" 59 ); 60 return sum; 61} 62 63/* 64 * computes the checksum of the TCP/UDP pseudo-header 65 * returns a 16-bit checksum, already complemented 66 */ 67static inline __sum16 csum_tcpudp_magic(unsigned long saddr, 68 unsigned long daddr, 69 unsigned short len, 70 unsigned short proto, 71 __wsum sum) 72{ 73 return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum)); 74} 75 76#undef _HAVE_ARCH_IPV6_CSUM 77 78/* 79 * Copy and checksum to user 80 */ 81#define HAVE_CSUM_COPY_USER 82extern __wsum csum_and_copy_to_user(const void *src, void *dst, int len, 83 __wsum sum, int *err_ptr); 84 85 86#endif /* _ASM_CHECKSUM_H */ 87