mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-21 16:29:59 +00:00
![Al Viro](/assets/img/avatar_default.png)
* sanitized prototypes, annotated * kill shift-by-16 in checksum calculation Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
210 lines
5.5 KiB
C
210 lines
5.5 KiB
C
#ifndef _PARISC_CHECKSUM_H
|
|
#define _PARISC_CHECKSUM_H
|
|
|
|
#include <linux/in6.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 __wsum csum_partial(const void *, int, __wsum);
|
|
|
|
/*
|
|
* 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 __wsum csum_partial_copy_nocheck(const void *, void *, int, __wsum);
|
|
|
|
/*
|
|
* this is a new version of the above that records errors it finds in *errp,
|
|
* but continues and zeros the rest of the buffer.
|
|
*/
|
|
extern __wsum csum_partial_copy_from_user(const void __user *src,
|
|
void *dst, int len, __wsum sum, int *errp);
|
|
|
|
/*
|
|
* Optimized for IP headers, which always checksum on 4 octet boundaries.
|
|
*
|
|
* Written by Randolph Chung <tausq@debian.org>, and then mucked with by
|
|
* LaMont Jones <lamont@debian.org>
|
|
*/
|
|
static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
|
|
{
|
|
unsigned int sum;
|
|
|
|
__asm__ __volatile__ (
|
|
" ldws,ma 4(%1), %0\n"
|
|
" addib,<= -4, %2, 2f\n"
|
|
"\n"
|
|
" ldws 4(%1), %%r20\n"
|
|
" ldws 8(%1), %%r21\n"
|
|
" add %0, %%r20, %0\n"
|
|
" ldws,ma 12(%1), %%r19\n"
|
|
" addc %0, %%r21, %0\n"
|
|
" addc %0, %%r19, %0\n"
|
|
"1: ldws,ma 4(%1), %%r19\n"
|
|
" addib,< 0, %2, 1b\n"
|
|
" addc %0, %%r19, %0\n"
|
|
"\n"
|
|
" extru %0, 31, 16, %%r20\n"
|
|
" extru %0, 15, 16, %%r21\n"
|
|
" addc %%r20, %%r21, %0\n"
|
|
" extru %0, 15, 16, %%r21\n"
|
|
" add %0, %%r21, %0\n"
|
|
" subi -1, %0, %0\n"
|
|
"2:\n"
|
|
: "=r" (sum), "=r" (iph), "=r" (ihl)
|
|
: "1" (iph), "2" (ihl)
|
|
: "r19", "r20", "r21" );
|
|
|
|
return (__force __sum16)sum;
|
|
}
|
|
|
|
/*
|
|
* Fold a partial checksum
|
|
*/
|
|
static inline __sum16 csum_fold(__wsum csum)
|
|
{
|
|
u32 sum = (__force u32)csum;
|
|
/* add the swapped two 16-bit halves of sum,
|
|
a possible carry from adding the two 16-bit halves,
|
|
will carry from the lower half into the upper half,
|
|
giving us the correct sum in the upper half. */
|
|
sum += (sum << 16) + (sum >> 16);
|
|
return (__force __sum16)(~sum >> 16);
|
|
}
|
|
|
|
static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
|
|
unsigned short len,
|
|
unsigned short proto,
|
|
__wsum sum)
|
|
{
|
|
__asm__(
|
|
" add %1, %0, %0\n"
|
|
" addc %2, %0, %0\n"
|
|
" addc %3, %0, %0\n"
|
|
" addc %%r0, %0, %0\n"
|
|
: "=r" (sum)
|
|
: "r" (daddr), "r"(saddr), "r"(proto+len), "0"(sum));
|
|
return sum;
|
|
}
|
|
|
|
/*
|
|
* computes the checksum of the TCP/UDP pseudo-header
|
|
* returns a 16-bit checksum, already complemented
|
|
*/
|
|
static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
|
|
unsigned short len,
|
|
unsigned short proto,
|
|
__wsum 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 __sum16 ip_compute_csum(const void *buf, int len)
|
|
{
|
|
return csum_fold (csum_partial(buf, len, 0));
|
|
}
|
|
|
|
|
|
#define _HAVE_ARCH_IPV6_CSUM
|
|
static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
|
|
const struct in6_addr *daddr,
|
|
__u32 len, unsigned short proto,
|
|
__wsum sum)
|
|
{
|
|
__asm__ __volatile__ (
|
|
|
|
#if BITS_PER_LONG > 32
|
|
|
|
/*
|
|
** We can execute two loads and two adds per cycle on PA 8000.
|
|
** But add insn's get serialized waiting for the carry bit.
|
|
** Try to keep 4 registers with "live" values ahead of the ALU.
|
|
*/
|
|
|
|
" ldd,ma 8(%1), %%r19\n" /* get 1st saddr word */
|
|
" ldd,ma 8(%2), %%r20\n" /* get 1st daddr word */
|
|
" add %8, %3, %3\n"/* add 16-bit proto + len */
|
|
" add %%r19, %0, %0\n"
|
|
" ldd,ma 8(%1), %%r21\n" /* 2cd saddr */
|
|
" ldd,ma 8(%2), %%r22\n" /* 2cd daddr */
|
|
" add,dc %%r20, %0, %0\n"
|
|
" add,dc %%r21, %0, %0\n"
|
|
" add,dc %%r22, %0, %0\n"
|
|
" add,dc %3, %0, %0\n" /* fold in proto+len | carry bit */
|
|
" extrd,u %0, 31, 32, %%r19\n" /* copy upper half down */
|
|
" depdi 0, 31, 32, %0\n" /* clear upper half */
|
|
" add %%r19, %0, %0\n" /* fold into 32-bits */
|
|
" addc 0, %0, %0\n" /* add carry */
|
|
|
|
#else
|
|
|
|
/*
|
|
** For PA 1.x, the insn order doesn't matter as much.
|
|
** Insn stream is serialized on the carry bit here too.
|
|
** result from the previous operation (eg r0 + x)
|
|
*/
|
|
|
|
" ldw,ma 4(%1), %%r19\n" /* get 1st saddr word */
|
|
" ldw,ma 4(%2), %%r20\n" /* get 1st daddr word */
|
|
" add %8, %3, %3\n" /* add 16-bit proto + len */
|
|
" add %%r19, %0, %0\n"
|
|
" ldw,ma 4(%1), %%r21\n" /* 2cd saddr */
|
|
" addc %%r20, %0, %0\n"
|
|
" ldw,ma 4(%2), %%r22\n" /* 2cd daddr */
|
|
" addc %%r21, %0, %0\n"
|
|
" ldw,ma 4(%1), %%r19\n" /* 3rd saddr */
|
|
" addc %%r22, %0, %0\n"
|
|
" ldw,ma 4(%2), %%r20\n" /* 3rd daddr */
|
|
" addc %%r19, %0, %0\n"
|
|
" ldw,ma 4(%1), %%r21\n" /* 4th saddr */
|
|
" addc %%r20, %0, %0\n"
|
|
" ldw,ma 4(%2), %%r22\n" /* 4th daddr */
|
|
" addc %%r21, %0, %0\n"
|
|
" addc %%r22, %0, %0\n"
|
|
" addc %3, %0, %0\n" /* fold in proto+len, catch carry */
|
|
|
|
#endif
|
|
: "=r" (sum), "=r" (saddr), "=r" (daddr), "=r" (len)
|
|
: "0" (sum), "1" (saddr), "2" (daddr), "3" (len), "r" (proto)
|
|
: "r19", "r20", "r21", "r22");
|
|
return csum_fold(sum);
|
|
}
|
|
|
|
/*
|
|
* Copy and checksum to user
|
|
*/
|
|
#define HAVE_CSUM_COPY_USER
|
|
static __inline__ __wsum csum_and_copy_to_user(const void *src,
|
|
void __user *dst,
|
|
int len, __wsum 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 (__force __wsum)-1;
|
|
}
|
|
|
|
return sum;
|
|
}
|
|
|
|
#endif
|
|
|