+++ /dev/null
-/*
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this archive
- * for more details.
- *
- * Copyright (C) 1995, 96, 97, 98, 99, 2001 by Ralf Baechle
- * Copyright (C) 1999 Silicon Graphics, Inc.
- * Copyright (C) 2001 Thiemo Seufer.
- * Copyright (C) 2002 Maciej W. Rozycki
- */
-#ifndef _ASM_CHECKSUM_H
-#define _ASM_CHECKSUM_H
-
-#include <linux/in6.h>
-
-#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
- */
-__wsum csum_partial(const void *buff, int len, __wsum sum);
-
-__wsum __csum_partial_copy_user(const void *src, void *dst,
- int len, __wsum sum, int *err_ptr);
-
-/*
- * this is a new version of the above that records errors it finds in *errp,
- * but continues and zeros the rest of the buffer.
- */
-static inline
-__wsum csum_partial_copy_from_user(const void __user *src, void *dst, int len,
- __wsum sum, int *err_ptr)
-{
- might_sleep();
- return __csum_partial_copy_user((__force void *)src, dst,
- len, sum, err_ptr);
-}
-
-/*
- * 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)
-{
- might_sleep();
- if (access_ok(VERIFY_WRITE, dst, len))
- return __csum_partial_copy_user(src, (__force void *)dst,
- len, sum, err_ptr);
- if (len)
- *err_ptr = -EFAULT;
-
- return (__force __wsum)-1; /* invalid checksum */
-}
-
-/*
- * the same as csum_partial, but copies from user space (but on MIPS
- * we have just one address space, so this is identical to the above)
- */
-__wsum csum_partial_copy_nocheck(const void *src, void *dst,
- int len, __wsum sum);
-
-/*
- * Fold a partial checksum without adding pseudo headers
- */
-static inline __sum16 csum_fold(__wsum sum)
-{
- __asm__(
- " .set push # csum_fold\n"
- " .set noat \n"
- " sll $1, %0, 16 \n"
- " addu %0, $1 \n"
- " sltu $1, %0, $1 \n"
- " srl %0, %0, 16 \n"
- " addu %0, $1 \n"
- " xori %0, 0xffff \n"
- " .set pop"
- : "=r" (sum)
- : "0" (sum));
-
- return (__force __sum16)sum;
-}
-
-/*
- * This is a version of ip_compute_csum() optimized for IP headers,
- * which always checksum on 4 octet boundaries.
- *
- * By Jorge Cwik <jorge@laser.satlink.net>, adapted for linux by
- * Arnt Gulbrandsen.
- */
-static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
-{
- const unsigned int *word = iph;
- const unsigned int *stop = word + ihl;
- unsigned int csum;
- int carry;
-
- csum = word[0];
- csum += word[1];
- carry = (csum < word[1]);
- csum += carry;
-
- csum += word[2];
- carry = (csum < word[2]);
- csum += carry;
-
- csum += word[3];
- carry = (csum < word[3]);
- csum += carry;
-
- word += 4;
- do {
- csum += *word;
- carry = (csum < *word);
- csum += carry;
- word++;
- } while (word != stop);
-
- return csum_fold(csum);
-}
-
-static inline __wsum csum_tcpudp_nofold(__be32 saddr,
- __be32 daddr, unsigned short len, unsigned short proto,
- __wsum sum)
-{
- __asm__(
- " .set push # csum_tcpudp_nofold\n"
- " .set noat \n"
-#ifdef CONFIG_32BIT
- " addu %0, %2 \n"
- " sltu $1, %0, %2 \n"
- " addu %0, $1 \n"
-
- " addu %0, %3 \n"
- " sltu $1, %0, %3 \n"
- " addu %0, $1 \n"
-
- " addu %0, %4 \n"
- " sltu $1, %0, %4 \n"
- " addu %0, $1 \n"
-#endif
-#ifdef CONFIG_64BIT
- " daddu %0, %2 \n"
- " daddu %0, %3 \n"
- " daddu %0, %4 \n"
- " dsll32 $1, %0, 0 \n"
- " daddu %0, $1 \n"
- " dsra32 %0, %0, 0 \n"
-#endif
- " .set pop"
- : "=r" (sum)
- : "0" ((__force unsigned long)daddr),
- "r" ((__force unsigned long)saddr),
-#ifdef __MIPSEL__
- "r" ((proto + len) << 8),
-#else
- "r" (proto + len),
-#endif
- "r" ((__force unsigned long)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 *buff, int len)
-{
- return csum_fold(csum_partial(buff, 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__(
- " .set push # csum_ipv6_magic\n"
- " .set noreorder \n"
- " .set noat \n"
- " addu %0, %5 # proto (long in network byte order)\n"
- " sltu $1, %0, %5 \n"
- " addu %0, $1 \n"
-
- " addu %0, %6 # csum\n"
- " sltu $1, %0, %6 \n"
- " lw %1, 0(%2) # four words source address\n"
- " addu %0, $1 \n"
- " addu %0, %1 \n"
- " sltu $1, %0, %1 \n"
-
- " lw %1, 4(%2) \n"
- " addu %0, $1 \n"
- " addu %0, %1 \n"
- " sltu $1, %0, %1 \n"
-
- " lw %1, 8(%2) \n"
- " addu %0, $1 \n"
- " addu %0, %1 \n"
- " sltu $1, %0, %1 \n"
-
- " lw %1, 12(%2) \n"
- " addu %0, $1 \n"
- " addu %0, %1 \n"
- " sltu $1, %0, %1 \n"
-
- " lw %1, 0(%3) \n"
- " addu %0, $1 \n"
- " addu %0, %1 \n"
- " sltu $1, %0, %1 \n"
-
- " lw %1, 4(%3) \n"
- " addu %0, $1 \n"
- " addu %0, %1 \n"
- " sltu $1, %0, %1 \n"
-
- " lw %1, 8(%3) \n"
- " addu %0, $1 \n"
- " addu %0, %1 \n"
- " sltu $1, %0, %1 \n"
-
- " lw %1, 12(%3) \n"
- " addu %0, $1 \n"
- " addu %0, %1 \n"
- " sltu $1, %0, %1 \n"
-
- " addu %0, $1 # Add final carry\n"
- " .set pop"
- : "=r" (sum), "=r" (proto)
- : "r" (saddr), "r" (daddr),
- "0" (htonl(len)), "1" (htonl(proto)), "r" (sum));
-
- return csum_fold(sum);
-}
-
-#endif /* _ASM_CHECKSUM_H */
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff