/* * include/asm-v850/checksum.h -- Checksum ops * * Copyright (C) 2001,2005 NEC Corporation * Copyright (C) 2001,2005 Miles Bader <miles@gnu.org> * * This file is subject to the terms and conditions of the GNU General * Public License. See the file COPYING in the main directory of this * archive for more details. * * Written by Miles Bader <miles@gnu.org> */ #ifndef __V850_CHECKSUM_H__ #define __V850_CHECKSUM_H__ /* * computes the checksum of a memory block at buff, length len, * and adds in "sum" (32-bit) * * returns a 32-bit number suitable for feeding into itself * or csum_tcpudp_magic * * this function must be called with even lengths, except * for the last fragment, which may be odd * * it's best to have buff aligned on a 32-bit boundary */ extern unsigned int csum_partial (const unsigned char * buff, int len, unsigned int sum); /* * the same as csum_partial, but copies from src while it * checksums * * here even more important to align src and dst on a 32-bit (or even * better 64-bit) boundary */ extern unsigned csum_partial_copy (const unsigned char *src, unsigned char *dst, int len, unsigned sum); /* * the same as csum_partial_copy, but copies from user space. * * here even more important to align src and dst on a 32-bit (or even * better 64-bit) boundary */ extern unsigned csum_partial_copy_from_user (const unsigned char *src, unsigned char *dst, int len, unsigned sum, int *csum_err); #define csum_partial_copy_nocheck(src, dst, len, sum) \ csum_partial_copy ((src), (dst), (len), (sum)) unsigned short ip_fast_csum (unsigned char *iph, unsigned int ihl); /* * Fold a partial checksum */ static inline unsigned int csum_fold (unsigned long sum) { unsigned int result; /* %0 %1 hsw %1, %0 H L L H add %1, %0 H L H+L+C H+L */ asm ("hsw %1, %0; add %1, %0" : "=&r" (result) : "r" (sum)); return (~result) >> 16; } /* * computes the checksum of the TCP/UDP pseudo-header * returns a 16-bit checksum, already complemented */ static inline unsigned int csum_tcpudp_nofold (unsigned long saddr, unsigned long daddr, unsigned short len, unsigned short proto, unsigned int sum) { int __carry; __asm__ ("add %2, %0;" "setf c, %1;" "add %1, %0;" "add %3, %0;" "setf c, %1;" "add %1, %0;" "add %4, %0;" "setf c, %1;" "add %1, %0" : "=&r" (sum), "=&r" (__carry) : "r" (daddr), "r" (saddr), "r" (ntohs (len) + (proto << 8)), "0" (sum)); return sum; } static inline unsigned short int csum_tcpudp_magic (unsigned long saddr, unsigned long daddr, unsigned short len, unsigned short proto, unsigned int sum) { return csum_fold (csum_tcpudp_nofold (saddr, daddr, len, proto, sum)); } /* * this routine is used for miscellaneous IP-like checksums, mainly * in icmp.c */ extern unsigned short ip_compute_csum (const unsigned char * buff, int len); #endif /* __V850_CHECKSUM_H__ */