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/* $Id: checksum.h,v 1.1.1.1 2004-04-15 02:40:34 phoenix Exp $ */

#ifndef __SPARC_CHECKSUM_H

#define __SPARC_CHECKSUM_H

/*  checksum.h:  IP/UDP/TCP checksum routines on the Sparc.

 *

 *  Copyright(C) 1995 Linus Torvalds

 *  Copyright(C) 1995 Miguel de Icaza

 *  Copyright(C) 1996 David S. Miller

 *  Copyright(C) 1996 Eddie C. Dost

 *  Copyright(C) 1997 Jakub Jelinek

 *

 * derived from:

 *      Alpha checksum c-code

 *      ix86 inline assembly

 *      RFC1071 Computing the Internet Checksum

 */

#include <linux/in6.h>

#include <asm/uaccess.h>

#include <asm/cprefix.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 * buff, int len, unsigned int sum);

/* the same as csum_partial, but copies from fs:src while it

 * checksums

 *

 * here even more important to align src and dst on a 32-bit (or even

 * better 64-bit) boundary

 */

/* FIXME: Remove these two macros ASAP */

#define csum_partial_copy(src, dst, len, sum) \

                       csum_partial_copy_nocheck(src,dst,len,sum)

#define csum_partial_copy_fromuser(s, d, l, w)  \

                         csum_partial_copy((char *) (s), (d), (l), (w))

extern unsigned int __csum_partial_copy_sparc_generic (const char *, char *);

static inline unsigned int

csum_partial_copy_nocheck (const char *src, char *dst, int len,

                           unsigned int sum)

{

        register unsigned int ret asm("o0") = (unsigned int)src;

        register char *d asm("o1") = dst;

        register int l asm("g1") = len;

        __asm__ __volatile__ (

                "call " C_LABEL_STR(__csum_partial_copy_sparc_generic) "\n\t"

                " mov %6, %%g7\n"

        : "=&r" (ret), "=&r" (d), "=&r" (l)

        : "0" (ret), "1" (d), "2" (l), "r" (sum)

        : "o2", "o3", "o4", "o5", "o7",

          "g2", "g3", "g4", "g5", "g7",

          "memory", "cc");

        return ret;

}

static inline unsigned int

csum_partial_copy_from_user(const char *src, char *dst, int len,

                            unsigned int sum, int *err)

  {

        if (!access_ok (VERIFY_READ, src, len)) {

                *err = -EFAULT;

                memset (dst, 0, len);

                return sum;

        } else {

                register unsigned int ret asm("o0") = (unsigned int)src;

                register char *d asm("o1") = dst;

                register int l asm("g1") = len;

                register unsigned int s asm("g7") = sum;

                __asm__ __volatile__ (

                ".section __ex_table,#alloc\n\t"

                ".align 4\n\t"

                ".word 1f,2\n\t"

                ".previous\n"

                "1:\n\t"

                "call " C_LABEL_STR(__csum_partial_copy_sparc_generic) "\n\t"

                " st %8, [%%sp + 64]\n"

                : "=&r" (ret), "=&r" (d), "=&r" (l), "=&r" (s)

                : "0" (ret), "1" (d), "2" (l), "3" (s), "r" (err)

                : "o2", "o3", "o4", "o5", "o7", "g2", "g3", "g4", "g5",

                  "cc", "memory");

                return ret;

        }

  }

static inline unsigned int

csum_partial_copy_to_user(const char *src, char *dst, int len,

                          unsigned int sum, int *err)

{

        if (!access_ok (VERIFY_WRITE, dst, len)) {

                *err = -EFAULT;

                return sum;

        } else {

                register unsigned int ret asm("o0") = (unsigned int)src;

                register char *d asm("o1") = dst;

                register int l asm("g1") = len;

                register unsigned int s asm("g7") = sum;

                __asm__ __volatile__ (

                ".section __ex_table,#alloc\n\t"

                ".align 4\n\t"

                ".word 1f,1\n\t"

                ".previous\n"

                "1:\n\t"

                "call " C_LABEL_STR(__csum_partial_copy_sparc_generic) "\n\t"

                " st %8, [%%sp + 64]\n"

                : "=&r" (ret), "=&r" (d), "=&r" (l), "=&r" (s)

                : "0" (ret), "1" (d), "2" (l), "3" (s), "r" (err)

                : "o2", "o3", "o4", "o5", "o7",

                  "g2", "g3", "g4", "g5",

                  "cc", "memory");

                return ret;

        }

}

#define HAVE_CSUM_COPY_USER

#define csum_and_copy_to_user csum_partial_copy_to_user

/* ihl is always 5 or greater, almost always is 5, and iph is word aligned

 * the majority of the time.

 */

static inline unsigned short ip_fast_csum(const unsigned char *iph,

                                          unsigned int ihl)

{

        unsigned short sum;

        /* Note: We must read %2 before we touch %0 for the first time,

         *       because GCC can legitimately use the same register for

         *       both operands.

         */

        __asm__ __volatile__("sub\t%2, 4, %%g4\n\t"

                             "ld\t[%1 + 0x00], %0\n\t"

                             "ld\t[%1 + 0x04], %%g2\n\t"

                             "ld\t[%1 + 0x08], %%g3\n\t"

                             "addcc\t%%g2, %0, %0\n\t"

                             "addxcc\t%%g3, %0, %0\n\t"

                             "ld\t[%1 + 0x0c], %%g2\n\t"

                             "ld\t[%1 + 0x10], %%g3\n\t"

                             "addxcc\t%%g2, %0, %0\n\t"

                             "addx\t%0, %%g0, %0\n"

                             "1:\taddcc\t%%g3, %0, %0\n\t"

                             "add\t%1, 4, %1\n\t"

                             "addxcc\t%0, %%g0, %0\n\t"

                             "subcc\t%%g4, 1, %%g4\n\t"

                             "be,a\t2f\n\t"

                             "sll\t%0, 16, %%g2\n\t"

                             "b\t1b\n\t"

                             "ld\t[%1 + 0x10], %%g3\n"

                             "2:\taddcc\t%0, %%g2, %%g2\n\t"

                             "srl\t%%g2, 16, %0\n\t"

                             "addx\t%0, %%g0, %0\n\t"

                             "xnor\t%%g0, %0, %0"

                             : "=r" (sum), "=&r" (iph)

                             : "r" (ihl), "1" (iph)

                             : "g2", "g3", "g4", "cc");

        return sum;

}

/* Fold a partial checksum without adding pseudo headers. */

static inline unsigned int csum_fold(unsigned int sum)

{

        unsigned int tmp;

        __asm__ __volatile__("addcc\t%0, %1, %1\n\t"

                             "srl\t%1, 16, %1\n\t"

                             "addx\t%1, %%g0, %1\n\t"

                             "xnor\t%%g0, %1, %0"

                             : "=&r" (sum), "=r" (tmp)

                             : "0" (sum), "1" (sum<<16)

                             : "cc");

        return sum;

}

static inline unsigned long csum_tcpudp_nofold(unsigned long saddr,

                                               unsigned long daddr,

                                               unsigned int len,

                                               unsigned short proto,

                                               unsigned int sum)

{

        __asm__ __volatile__("addcc\t%1, %0, %0\n\t"

                             "addxcc\t%2, %0, %0\n\t"

                             "addxcc\t%3, %0, %0\n\t"

                             "addx\t%0, %%g0, %0\n\t"

                             : "=r" (sum), "=r" (saddr)

                             : "r" (daddr), "r" ((proto<<16)+len), "0" (sum),

                               "1" (saddr)

                             : "cc");

        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));

}

#define _HAVE_ARCH_IPV6_CSUM

static inline unsigned short int csum_ipv6_magic(struct in6_addr *saddr,

                                                 struct in6_addr *daddr,

                                                 __u32 len,

                                                 unsigned short proto,

                                                 unsigned int sum)

{

        __asm__ __volatile__ (

                "addcc  %3, %4, %%g4\n\t"

                "addxcc %5, %%g4, %%g4\n\t"

                "ld     [%2 + 0x0c], %%g2\n\t"

                "ld     [%2 + 0x08], %%g3\n\t"

                "addxcc %%g2, %%g4, %%g4\n\t"

                "ld     [%2 + 0x04], %%g2\n\t"

                "addxcc %%g3, %%g4, %%g4\n\t"

                "ld     [%2 + 0x00], %%g3\n\t"

                "addxcc %%g2, %%g4, %%g4\n\t"

                "ld     [%1 + 0x0c], %%g2\n\t"

                "addxcc %%g3, %%g4, %%g4\n\t"

                "ld     [%1 + 0x08], %%g3\n\t"

                "addxcc %%g2, %%g4, %%g4\n\t"

                "ld     [%1 + 0x04], %%g2\n\t"

                "addxcc %%g3, %%g4, %%g4\n\t"

                "ld     [%1 + 0x00], %%g3\n\t"

                "addxcc %%g2, %%g4, %%g4\n\t"

                "addxcc %%g3, %%g4, %0\n\t"

                "addx   0, %0, %0\n"

                : "=&r" (sum)

                : "r" (saddr), "r" (daddr),

                  "r"(htonl(len)), "r"(htonl(proto)), "r"(sum)

                : "g2", "g3", "g4", "cc");

        return csum_fold(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 /* !(__SPARC_CHECKSUM_H) */