265 lines
7.6 KiB
C
265 lines
7.6 KiB
C
#ifndef _S390_CHECKSUM_H
|
|
#define _S390_CHECKSUM_H
|
|
|
|
/*
|
|
* include/asm-s390/checksum.h
|
|
* S390 fast network checksum routines
|
|
* see also arch/S390/lib/checksum.c
|
|
*
|
|
* S390 version
|
|
* Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
|
|
* Author(s): Ulrich Hild (first version)
|
|
* Martin Schwidefsky (heavily optimized CKSM version)
|
|
* D.J. Barrow (third attempt)
|
|
*/
|
|
|
|
#include <asm/uaccess.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
|
|
*/
|
|
static inline unsigned int
|
|
csum_partial(const unsigned char * buff, int len, unsigned int sum)
|
|
{
|
|
/*
|
|
* Experiments with ethernet and slip connections show that buf
|
|
* is aligned on either a 2-byte or 4-byte boundary.
|
|
*/
|
|
#ifndef __s390x__
|
|
register_pair rp;
|
|
|
|
rp.subreg.even = (unsigned long) buff;
|
|
rp.subreg.odd = (unsigned long) len;
|
|
__asm__ __volatile__ (
|
|
"0: cksm %0,%1\n" /* do checksum on longs */
|
|
" jo 0b\n"
|
|
: "+&d" (sum), "+&a" (rp) : : "cc", "memory" );
|
|
#else /* __s390x__ */
|
|
__asm__ __volatile__ (
|
|
" lgr 2,%1\n" /* address in gpr 2 */
|
|
" lgfr 3,%2\n" /* length in gpr 3 */
|
|
"0: cksm %0,2\n" /* do checksum on longs */
|
|
" jo 0b\n"
|
|
: "+&d" (sum)
|
|
: "d" (buff), "d" (len)
|
|
: "cc", "memory", "2", "3" );
|
|
#endif /* __s390x__ */
|
|
return sum;
|
|
}
|
|
|
|
/*
|
|
* csum_partial as an inline function
|
|
*/
|
|
static inline unsigned int
|
|
csum_partial_inline(const unsigned char * buff, int len, unsigned int sum)
|
|
{
|
|
#ifndef __s390x__
|
|
register_pair rp;
|
|
|
|
rp.subreg.even = (unsigned long) buff;
|
|
rp.subreg.odd = (unsigned long) len;
|
|
__asm__ __volatile__ (
|
|
"0: cksm %0,%1\n" /* do checksum on longs */
|
|
" jo 0b\n"
|
|
: "+&d" (sum), "+&a" (rp) : : "cc", "memory" );
|
|
#else /* __s390x__ */
|
|
__asm__ __volatile__ (
|
|
" lgr 2,%1\n" /* address in gpr 2 */
|
|
" lgfr 3,%2\n" /* length in gpr 3 */
|
|
"0: cksm %0,2\n" /* do checksum on longs */
|
|
" jo 0b\n"
|
|
: "+&d" (sum)
|
|
: "d" (buff), "d" (len)
|
|
: "cc", "memory", "2", "3" );
|
|
#endif /* __s390x__ */
|
|
return 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
|
|
*
|
|
* Copy from userspace and compute checksum. If we catch an exception
|
|
* then zero the rest of the buffer.
|
|
*/
|
|
static inline unsigned int
|
|
csum_partial_copy_from_user(const char __user *src, char *dst,
|
|
int len, unsigned int sum,
|
|
int *err_ptr)
|
|
{
|
|
int missing;
|
|
|
|
missing = copy_from_user(dst, src, len);
|
|
if (missing) {
|
|
memset(dst + len - missing, 0, missing);
|
|
*err_ptr = -EFAULT;
|
|
}
|
|
|
|
return csum_partial(dst, len, sum);
|
|
}
|
|
|
|
|
|
static inline unsigned int
|
|
csum_partial_copy_nocheck (const char *src, char *dst, int len, unsigned int sum)
|
|
{
|
|
memcpy(dst,src,len);
|
|
return csum_partial_inline(dst, len, sum);
|
|
}
|
|
|
|
/*
|
|
* Fold a partial checksum without adding pseudo headers
|
|
*/
|
|
static inline unsigned short
|
|
csum_fold(unsigned int sum)
|
|
{
|
|
#ifndef __s390x__
|
|
register_pair rp;
|
|
|
|
__asm__ __volatile__ (
|
|
" slr %N1,%N1\n" /* %0 = H L */
|
|
" lr %1,%0\n" /* %0 = H L, %1 = H L 0 0 */
|
|
" srdl %1,16\n" /* %0 = H L, %1 = 0 H L 0 */
|
|
" alr %1,%N1\n" /* %0 = H L, %1 = L H L 0 */
|
|
" alr %0,%1\n" /* %0 = H+L+C L+H */
|
|
" srl %0,16\n" /* %0 = H+L+C */
|
|
: "+&d" (sum), "=d" (rp) : : "cc" );
|
|
#else /* __s390x__ */
|
|
__asm__ __volatile__ (
|
|
" sr 3,3\n" /* %0 = H*65536 + L */
|
|
" lr 2,%0\n" /* %0 = H L, R2/R3 = H L / 0 0 */
|
|
" srdl 2,16\n" /* %0 = H L, R2/R3 = 0 H / L 0 */
|
|
" alr 2,3\n" /* %0 = H L, R2/R3 = L H / L 0 */
|
|
" alr %0,2\n" /* %0 = H+L+C L+H */
|
|
" srl %0,16\n" /* %0 = H+L+C */
|
|
: "+&d" (sum) : : "cc", "2", "3");
|
|
#endif /* __s390x__ */
|
|
return ((unsigned short) ~sum);
|
|
}
|
|
|
|
/*
|
|
* This is a version of ip_compute_csum() optimized for IP headers,
|
|
* which always checksum on 4 octet boundaries.
|
|
*
|
|
*/
|
|
static inline unsigned short
|
|
ip_fast_csum(unsigned char *iph, unsigned int ihl)
|
|
{
|
|
unsigned long sum;
|
|
#ifndef __s390x__
|
|
register_pair rp;
|
|
|
|
rp.subreg.even = (unsigned long) iph;
|
|
rp.subreg.odd = (unsigned long) ihl*4;
|
|
__asm__ __volatile__ (
|
|
" sr %0,%0\n" /* set sum to zero */
|
|
"0: cksm %0,%1\n" /* do checksum on longs */
|
|
" jo 0b\n"
|
|
: "=&d" (sum), "+&a" (rp) : : "cc", "memory" );
|
|
#else /* __s390x__ */
|
|
__asm__ __volatile__ (
|
|
" slgr %0,%0\n" /* set sum to zero */
|
|
" lgr 2,%1\n" /* address in gpr 2 */
|
|
" lgfr 3,%2\n" /* length in gpr 3 */
|
|
"0: cksm %0,2\n" /* do checksum on ints */
|
|
" jo 0b\n"
|
|
: "=&d" (sum)
|
|
: "d" (iph), "d" (ihl*4)
|
|
: "cc", "memory", "2", "3" );
|
|
#endif /* __s390x__ */
|
|
return csum_fold(sum);
|
|
}
|
|
|
|
/*
|
|
* computes the checksum of the TCP/UDP pseudo-header
|
|
* returns a 32-bit checksum
|
|
*/
|
|
static inline unsigned int
|
|
csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr,
|
|
unsigned short len, unsigned short proto,
|
|
unsigned int sum)
|
|
{
|
|
#ifndef __s390x__
|
|
__asm__ __volatile__ (
|
|
" alr %0,%1\n" /* sum += saddr */
|
|
" brc 12,0f\n"
|
|
" ahi %0,1\n" /* add carry */
|
|
"0:"
|
|
: "+&d" (sum) : "d" (saddr) : "cc" );
|
|
__asm__ __volatile__ (
|
|
" alr %0,%1\n" /* sum += daddr */
|
|
" brc 12,1f\n"
|
|
" ahi %0,1\n" /* add carry */
|
|
"1:"
|
|
: "+&d" (sum) : "d" (daddr) : "cc" );
|
|
__asm__ __volatile__ (
|
|
" alr %0,%1\n" /* sum += (len<<16) + (proto<<8) */
|
|
" brc 12,2f\n"
|
|
" ahi %0,1\n" /* add carry */
|
|
"2:"
|
|
: "+&d" (sum)
|
|
: "d" (((unsigned int) len<<16) + (unsigned int) proto)
|
|
: "cc" );
|
|
#else /* __s390x__ */
|
|
__asm__ __volatile__ (
|
|
" lgfr %0,%0\n"
|
|
" algr %0,%1\n" /* sum += saddr */
|
|
" brc 12,0f\n"
|
|
" aghi %0,1\n" /* add carry */
|
|
"0: algr %0,%2\n" /* sum += daddr */
|
|
" brc 12,1f\n"
|
|
" aghi %0,1\n" /* add carry */
|
|
"1: algfr %0,%3\n" /* sum += (len<<16) + proto */
|
|
" brc 12,2f\n"
|
|
" aghi %0,1\n" /* add carry */
|
|
"2: srlg 0,%0,32\n"
|
|
" alr %0,0\n" /* fold to 32 bits */
|
|
" brc 12,3f\n"
|
|
" ahi %0,1\n" /* add carry */
|
|
"3: llgfr %0,%0"
|
|
: "+&d" (sum)
|
|
: "d" (saddr), "d" (daddr),
|
|
"d" (((unsigned int) len<<16) + (unsigned int) proto)
|
|
: "cc", "0" );
|
|
#endif /* __s390x__ */
|
|
return sum;
|
|
}
|
|
|
|
/*
|
|
* computes the checksum of the TCP/UDP pseudo-header
|
|
* returns a 16-bit checksum, already complemented
|
|
*/
|
|
|
|
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
|
|
*/
|
|
|
|
static inline unsigned short
|
|
ip_compute_csum(unsigned char * buff, int len)
|
|
{
|
|
return csum_fold(csum_partial(buff, len, 0));
|
|
}
|
|
|
|
#endif /* _S390_CHECKSUM_H */
|
|
|
|
|