cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

checksum.h (1774B)

      1/*
      2 * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
      3 * Copyright (C) 2004 Microtronix Datacom Ltd.
      4 *
      5 * This file is subject to the terms and conditions of the GNU General Public
      6 * License. See the file "COPYING" in the main directory of this archive
      7 * for more details.
      8 */
      9
     10#ifndef _ASM_NIOS_CHECKSUM_H
     11#define _ASM_NIOS_CHECKSUM_H
     12
     13/* Take these from lib/checksum.c */
     14extern __wsum csum_partial(const void *buff, int len, __wsum sum);
     15extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
     16extern __sum16 ip_compute_csum(const void *buff, int len);
     17
     18/*
     19 * Fold a partial checksum
     20 */
     21static inline __sum16 csum_fold(__wsum sum)
     22{
     23	__asm__ __volatile__(
     24		"add	%0, %1, %0\n"
     25		"cmpltu	r8, %0, %1\n"
     26		"srli	%0, %0, 16\n"
     27		"add	%0, %0, r8\n"
     28		"nor	%0, %0, %0\n"
     29		: "=r" (sum)
     30		: "r" (sum << 16), "0" (sum)
     31		: "r8");
     32	return (__force __sum16) sum;
     33}
     34
     35/*
     36 * computes the checksum of the TCP/UDP pseudo-header
     37 * returns a 16-bit checksum, already complemented
     38 */
     39#define csum_tcpudp_nofold csum_tcpudp_nofold
     40static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
     41					__u32 len, __u8 proto,
     42					__wsum sum)
     43{
     44	__asm__ __volatile__(
     45		"add	%0, %1, %0\n"
     46		"cmpltu	r8, %0, %1\n"
     47		"add	%0, %0, r8\n"	/* add carry */
     48		"add	%0, %2, %0\n"
     49		"cmpltu	r8, %0, %2\n"
     50		"add	%0, %0, r8\n"	/* add carry */
     51		"add	%0, %3, %0\n"
     52		"cmpltu	r8, %0, %3\n"
     53		"add	%0, %0, r8\n"	/* add carry */
     54		: "=r" (sum), "=r" (saddr)
     55		: "r" (daddr), "r" ((len + proto) << 8),
     56		  "0" (sum),
     57		  "1" (saddr)
     58		: "r8");
     59
     60	return sum;
     61}
     62
     63static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
     64					__u32 len, __u8 proto,
     65					__wsum sum)
     66{
     67	return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum));
     68}
     69
     70#endif /* _ASM_NIOS_CHECKSUM_H */