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- /* $Id: checksum.h,v 1.29 1999/03/21 05:22:07 davem 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 <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(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 *);
-
- extern __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) "
- mov %4, %%g7
- " : "=r" (ret) : "0" (ret), "r" (d), "r" (l), "r" (sum) :
- "o1", "o2", "o3", "o4", "o5", "o7", "g1", "g2", "g3", "g4", "g5", "g7");
- return ret;
- }
-
- extern __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
- .align 4
- .word 1f,2
- .previous
- 1:
- call " C_LABEL_STR(__csum_partial_copy_sparc_generic) "
- st %5, [%%sp + 64]
- " : "=r" (ret) : "0" (ret), "r" (d), "r" (l), "r" (s), "r" (err) :
- "o1", "o2", "o3", "o4", "o5", "o7", "g1", "g2", "g3", "g4", "g5", "g7");
- return ret;
- }
- }
-
- extern __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
- .align 4
- .word 1f,1
- .previous
- 1:
- call " C_LABEL_STR(__csum_partial_copy_sparc_generic) "
- st %5, [%%sp + 64]
- " : "=r" (ret) : "0" (ret), "r" (d), "r" (l), "r" (s), "r" (err) :
- "o1", "o2", "o3", "o4", "o5", "o7", "g1", "g2", "g3", "g4", "g5", "g7");
- 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.
- */
- extern __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. */
- extern __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;
- }
-
- extern __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,
- __u16 len,
- unsigned short proto,
- unsigned int sum)
- {
- __asm__ __volatile__ ("
- addcc %3, %4, %%g4
- addxcc %5, %%g4, %%g4
- ld [%2 + 0x0c], %%g2
- ld [%2 + 0x08], %%g3
- addxcc %%g2, %%g4, %%g4
- ld [%2 + 0x04], %%g2
- addxcc %%g3, %%g4, %%g4
- ld [%2 + 0x00], %%g3
- addxcc %%g2, %%g4, %%g4
- ld [%1 + 0x0c], %%g2
- addxcc %%g3, %%g4, %%g4
- ld [%1 + 0x08], %%g3
- addxcc %%g2, %%g4, %%g4
- ld [%1 + 0x04], %%g2
- addxcc %%g3, %%g4, %%g4
- ld [%1 + 0x00], %%g3
- addxcc %%g2, %%g4, %%g4
- addxcc %%g3, %%g4, %0
- addx 0, %0, %0
- "
- : "=&r" (sum)
- : "r" (saddr), "r" (daddr),
- "r"(htonl((__u32) (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 */
- extern __inline__ unsigned short ip_compute_csum(unsigned char * buff, int len)
- {
- return csum_fold(csum_partial(buff, len, 0));
- }
-
- #endif /* !(__SPARC_CHECKSUM_H) */
-