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author | Kumar Gala <galak@freescale.com> | 2005-10-20 11:44:46 -0500 |
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committer | Paul Mackerras <paulus@samba.org> | 2005-10-26 15:54:31 +1000 |
commit | d95bbcb3a344b3eb84b45d162c0a20348f0af37f (patch) | |
tree | 036e03b868b09e3b064489ff7d8f2ccca26a9dda /include/asm-powerpc/checksum.h | |
parent | 60dda2565bbf31bbe662fd143a41c861b7a190cf (diff) | |
download | linux-d95bbcb3a344b3eb84b45d162c0a20348f0af37f.tar.gz linux-d95bbcb3a344b3eb84b45d162c0a20348f0af37f.tar.bz2 linux-d95bbcb3a344b3eb84b45d162c0a20348f0af37f.zip |
[PATCH] powerpc: merge include/asm-ppc*/checksum.h into include/asm-powerpc/checksum.h
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'include/asm-powerpc/checksum.h')
-rw-r--r-- | include/asm-powerpc/checksum.h | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/include/asm-powerpc/checksum.h b/include/asm-powerpc/checksum.h new file mode 100644 index 000000000000..d8354d8a49ce --- /dev/null +++ b/include/asm-powerpc/checksum.h @@ -0,0 +1,132 @@ +#ifndef _ASM_POWERPC_CHECKSUM_H +#define _ASM_POWERPC_CHECKSUM_H + +/* + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +/* + * This is a version of ip_compute_csum() optimized for IP headers, + * which always checksum on 4 octet boundaries. ihl is the number + * of 32-bit words and is always >= 5. + */ +extern unsigned short ip_fast_csum(unsigned char * iph, unsigned int ihl); + +/* + * computes the checksum of the TCP/UDP pseudo-header + * returns a 16-bit checksum, already complemented + */ +extern unsigned short csum_tcpudp_magic(unsigned long saddr, + unsigned long daddr, + unsigned short len, + unsigned short proto, + unsigned int sum); + +/* + * 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); + +/* + * Computes the checksum of a memory block at src, length len, + * and adds in "sum" (32-bit), while copying the block to dst. + * If an access exception occurs on src or dst, it stores -EFAULT + * to *src_err or *dst_err respectively (if that pointer is not + * NULL), and, for an error on src, zeroes the rest of dst. + * + * Like csum_partial, this must be called with even lengths, + * except for the last fragment. + */ +extern unsigned int csum_partial_copy_generic(const char *src, char *dst, + int len, unsigned int sum, + int *src_err, int *dst_err); +/* + * the same as csum_partial, but copies from src to dst while it + * checksums. + */ +unsigned int csum_partial_copy_nocheck(const char *src, + char *dst, + int len, + unsigned int sum); + +#define csum_partial_copy_from_user(src, dst, len, sum, errp) \ + csum_partial_copy_generic((src), (dst), (len), (sum), (errp), NULL) + +#define csum_partial_copy_nocheck(src, dst, len, sum) \ + csum_partial_copy_generic((src), (dst), (len), (sum), NULL, NULL) + + +/* + * turns a 32-bit partial checksum (e.g. from csum_partial) into a + * 1's complement 16-bit checksum. + */ +static inline unsigned int csum_fold(unsigned int sum) +{ + unsigned int tmp; + + /* swap the two 16-bit halves of sum */ + __asm__("rlwinm %0,%1,16,0,31" : "=r" (tmp) : "r" (sum)); + /* if there is a carry from adding the two 16-bit halves, + it will carry from the lower half into the upper half, + giving us the correct sum in the upper half. */ + sum = ~(sum + tmp) >> 16; + return 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)); +} + +#ifdef __powerpc64__ +static inline u32 csum_tcpudp_nofold(u32 saddr, + u32 daddr, + unsigned short len, + unsigned short proto, + unsigned int sum) +{ + unsigned long s = sum; + + s += saddr; + s += daddr; + s += (proto << 16) + len; + s += (s >> 32); + return (u32) s; +} +#else +static inline unsigned long csum_tcpudp_nofold(unsigned long saddr, + unsigned long daddr, + unsigned short len, + unsigned short proto, + unsigned int sum) +{ + __asm__("\n\ + addc %0,%0,%1 \n\ + adde %0,%0,%2 \n\ + adde %0,%0,%3 \n\ + addze %0,%0 \n\ + " + : "=r" (sum) + : "r" (daddr), "r"(saddr), "r"((proto<<16)+len), "0"(sum)); + return sum; +} + +#endif +#endif |