freebsd-dev/sys/arm/include/in_cksum.h
Mark Johnston ecbbe83144 netinet: Deduplicate most in_cksum() implementations
in_cksum() and related routines are implemented separately for each
platform, but only i386 and arm have optimized versions.  Other
platforms' copies of in_cksum.c are identical except for style
differences and support for big-endian CPUs.

Deduplicate the implementations for the rest of the platforms.  This
will make it easier to implement in_cksum() for unmapped mbufs.  On arm
and i386, define HAVE_MD_IN_CKSUM to mean that the MI implementation is
not to be compiled.

No functional change intended.

Reviewed by:	kp, glebius
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D33095
2021-11-24 13:31:16 -05:00

70 lines
2.5 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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.
* 3. 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.
*
* 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
* $FreeBSD$
*/
#ifndef _MACHINE_IN_CKSUM_H_
#define _MACHINE_IN_CKSUM_H_ 1
#include <sys/cdefs.h>
#ifdef _KERNEL
#define HAVE_MD_IN_CKSUM
u_short in_cksum(struct mbuf *m, int len);
u_short in_addword(u_short sum, u_short b);
u_short in_cksum_skip(struct mbuf *m, int len, int skip);
u_int do_cksum(const void *, int);
#if defined(IPVERSION) && (IPVERSION == 4)
u_int in_cksum_hdr(const struct ip *);
#endif
static __inline u_short
in_pseudo(u_int sum, u_int b, u_int c)
{
__asm __volatile("adds %0, %0, %1\n"
"adcs %0, %0, %2\n"
"adc %0, %0, #0\n"
: "+r" (sum)
: "r" (b), "r" (c));
sum = (sum & 0xffff) + (sum >> 16);
if (sum > 0xffff)
sum -= 0xffff;
return (sum);
}
#endif /* _KERNEL */
#endif /* _MACHINE_IN_CKSUM_H_ */