FreeBSD/Linux Kernel Cross Reference
sys/sparc64/include/in_cksum.h

     /*-
      * Copyright (c) 1990 The Regents of the University of California.
      * All rights reserved.
      *
      * Redistribution and use in source and binary forms, with or without
      * modification, are permitted provided that the following conditions
      * are met:
      * 1. Redistributions of source code must retain the above copyright
      *    notice, this list of conditions and the following disclaimer.
     * 2. Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in the
     *    documentation and/or other materials provided with the distribution.
     * 4. Neither the name of the University nor the names of its contributors
     *    may be used to endorse or promote products derived from this software
     *    without specific prior written permission.
     *
     * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     * SUCH DAMAGE.
     */
    /*-
     * Copyright (c) 2001 by Thomas Moestl <tmm@FreeBSD.org>.
     * All rights reserved.
     *
     * Redistribution and use in source and binary forms, with or without
     * modification, are permitted provided that the following conditions
     * are met:
     * 1. Redistributions of source code must retain the above copyright
     *    notice, this list of conditions and the following disclaimer.
     * 2. Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in the
     *    documentation and/or other materials provided with the distribution.
     *
     * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
     * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
     * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
     * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
     * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
     * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     *
     *      from tahoe:     in_cksum.c      1.2     86/01/05
     *      from:           @(#)in_cksum.c  1.3 (Berkeley) 1/19/91
     *      from: Id: in_cksum.c,v 1.8 1995/12/03 18:35:19 bde Exp
     *      from: FreeBSD: src/sys/alpha/include/in_cksum.h,v 1.5 2000/05/06
     *
     * $FreeBSD: releng/6.4/sys/sparc64/include/in_cksum.h 180301 2008-07-05 16:28:52Z marius $
     */
    
    #ifndef _MACHINE_IN_CKSUM_H_
    #define _MACHINE_IN_CKSUM_H_    1
    
    #include <sys/cdefs.h>
    
    #define in_cksum(m, len)        in_cksum_skip(m, len, 0)
    
    static __inline void
    in_cksum_update(struct ip *ip)
    {
            int __tmp;
    
            __tmp = (int)ip->ip_sum + 1;
            ip->ip_sum = __tmp + (__tmp >> 16);
    }
    
    static __inline u_short
    in_addword(u_short sum, u_short b)
    {
            u_long __ret, __tmp;
    
            __asm(
                "sll %2, 16, %0\n"
                "sll %3, 16, %1\n"
                "addcc %0, %1, %0\n"
                "srl %0, 16, %0\n"
                "addc %0, 0, %0\n"
                : "=&r" (__ret), "=&r" (__tmp) : "r" (sum), "r" (b) : "cc");
            return (__ret);
    }
    
    static __inline u_short
    in_pseudo(u_int sum, u_int b, u_int c)
    {
            u_long __tmp;
    
            __asm(
                "addcc %0, %3, %0\n"
                "addccc %0, %4, %0\n"
               "addc %0, 0, %0\n"
               "sll %0, 16, %1\n"
               "addcc %0, %1, %0\n"
               "srl %0, 16, %0\n"
               "addc %0, 0, %0\n"
               : "=r" (sum), "=&r" (__tmp) : "" (sum), "r" (b), "r" (c) : "cc");
           return (sum);
   }
   
   static __inline u_int
   in_cksum_hdr(struct ip *ip)
   {
           u_long __ret, __tmp1, __tmp2, __tmp3, __tmp4;
   
           /*
            * Use 32-bit memory accesses and additions - addition with carry only
            * works for 32 bits, and fixing up alignment issues for 64 is probably
            * more trouble than it's worth.
            * This may read outside of the ip header, but does not cross a page
            * boundary in doing so, so that should be OK.
            * Actually, this specialized implementation might be overkill - using
            * a generic implementation for both in_cksum_skip and in_cksum_hdr
            * should not be too much more expensive.
            */
   #define __LD_ADD(addr, tmp, sum, offs, mod)                             \
       "lduw [" #addr " + " #offs "], " #tmp "\n"                          \
       "add" # mod " " #sum ", " #tmp ", " #sum "\n"
   
           __asm(
               "and %5, 3, %3\n"
               "andn %5, 3, %1\n"
               "brz,pt %3, 0f\n"
               " lduw [%1], %0\n"
               "mov 4, %4\n"
               "sub %4, %3, %4\n"
               "sll %4, 3, %4\n"           /* fix up unaligned buffers */
               "mov 1, %2\n"
               "sll %2, %4, %4\n"
               "sub %4, 1, %4\n"
               "lduw [%1 + 20], %2\n"
               "andn %2, %4, %2\n"
               "and %0, %4, %0\n"
               "or %0, %2, %0\n"
               "0:\n"
               __LD_ADD(%1, %2, %0, 4, cc)
               __LD_ADD(%1, %2, %0, 8, ccc)
               __LD_ADD(%1, %2, %0, 12, ccc)
               __LD_ADD(%1, %2, %0, 16, ccc)
               "addc %0, 0, %0\n"          /* reduce */
               "1:\n"
               "sll %0, 16, %2\n"
               "addcc %0, %2, %0\n"
               "srl %0, 16, %0\n"
               "addc %0, 0, %0\n"
               "andcc %3, 1, %3\n"         /* need to byte-swap? */
               "clr %3\n"
               "bne,a,pn %%xcc, 1b\n"
               " sll %0, 8, %0\n"
               "not %0\n"
               "sll %0, 16, %0\n"
               "srl %0, 16, %0\n"
               : "=&r" (__ret), "=r" (__tmp1), "=&r" (__tmp2), "=&r" (__tmp3),
               "=&r" (__tmp4) : "1" (ip) : "cc");
   #undef __LD_ADD
           return (__ret);
   }
   
   u_short in_cksum_skip(struct mbuf *m, int len, int skip);
   
   #endif /* _MACHINE_IN_CKSUM_H_ */

Cache object: 0690f31da6387280f2b69d99849311a5