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#ifndef _PARISC_CHECKSUM_H
#define _PARISC_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 *, int, unsigned int);
/*
* 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 int csum_partial_copy(const char *, char *, int, unsigned int);
/*
* the same as csum_partial, but copies from user space
*
* this is obsolete and will go away.
*/
#define csum_partial_copy_fromuser csum_partial_copy
/*
* this is a new version of the above that records errors it finds in *errp,
* but continues and zeros the rest of the buffer.
*/
unsigned int csum_partial_copy_from_user(const char *src, char *dst, int len, unsigned int sum, int *errp);
/*
* Note: when you get a NULL pointer exception here this means someone
* passed in an incorrect kernel address to one of these functions.
*
* If you use these functions directly please don't forget the
* verify_area().
*/
extern __inline__
unsigned int csum_partial_copy_nocheck (const char *src, char *dst,
int len, int sum)
{
return csum_partial_copy (src, dst, len, sum);
}
/*
* Optimized for IP headers, which always checksum on 4 octet boundaries.
*
* Written by Randolph Chung <tausq@debian.org>
*/
static inline unsigned short ip_fast_csum(unsigned char * iph,
unsigned int ihl) {
unsigned int sum;
__asm__ __volatile__ ("
ldws,ma 4(%1), %0
addi -4, %2, %2
comib,>= 0, %2, 2f
ldws,ma 4(%1), %%r19
add %0, %%r19, %0
ldws,ma 4(%1), %%r19
addc %0, %%r19, %0
ldws,ma 4(%1), %%r19
addc %0, %%r19, %0
1: ldws,ma 4(%1), %%r19
addib,<> -1, %2, 1b
addc %0, %%r19, %0
addc %0, %%r0, %0
zdepi -1, 31, 16, %%r19
and %0, %%r19, %%r20
extru %0, 15, 16, %%r21
add %%r20, %%r21, %0
and %0, %%r19, %%r20
extru %0, 15, 16, %%r21
add %%r20, %%r21, %0
subi -1, %0, %0
2:
"
: "=r" (sum), "=r" (iph), "=r" (ihl)
: "1" (iph), "2" (ihl)
: "r19", "r20", "r21" );
return(sum);
}
/*
* Fold a partial checksum
*/
static inline unsigned int csum_fold(unsigned int sum)
{
sum = (sum & 0xffff) + (sum >> 16);
sum = (sum & 0xffff) + (sum >> 16);
return ~sum;
}
static inline unsigned long csum_tcpudp_nofold(unsigned long saddr,
unsigned long daddr,
unsigned short len,
unsigned short proto,
unsigned int sum)
{
__asm__("
add %1, %0, %0
addc %2, %0, %0
addc %3, %0, %0
addc %%r0, %0, %0 "
: "=r" (sum)
: "r" (daddr), "r"(saddr), "r"((proto<<16)+len), "0"(sum));
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 * buf, int len) {
return csum_fold (csum_partial(buf, len, 0));
}
#define _HAVE_ARCH_IPV6_CSUM
static __inline__ unsigned short int csum_ipv6_magic(struct in6_addr *saddr,
struct in6_addr *daddr,
__u16 len,
unsigned short proto,
unsigned int sum)
{
BUG();
return csum_fold(sum);
}
/*
* Copy and checksum to user
*/
#define HAVE_CSUM_COPY_USER
static __inline__ unsigned int csum_and_copy_to_user (const char *src, char *dst,
int len, int sum, int *err_ptr)
{
/* code stolen from include/asm-mips64 */
sum = csum_partial(src, len, sum);
if (copy_to_user(dst, src, len)) {
*err_ptr = -EFAULT;
return -1;
}
return sum;
}
#endif
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