From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- arch/ia64/lib/checksum.c | 102 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 102 insertions(+) create mode 100644 arch/ia64/lib/checksum.c (limited to 'arch/ia64/lib/checksum.c') diff --git a/arch/ia64/lib/checksum.c b/arch/ia64/lib/checksum.c new file mode 100644 index 000000000000..beb11721d9f5 --- /dev/null +++ b/arch/ia64/lib/checksum.c @@ -0,0 +1,102 @@ +/* + * Network checksum routines + * + * Copyright (C) 1999, 2003 Hewlett-Packard Co + * Stephane Eranian + * + * Most of the code coming from arch/alpha/lib/checksum.c + * + * This file contains network checksum routines that are better done + * in an architecture-specific manner due to speed.. + */ + +#include +#include + +#include + +static inline unsigned short +from64to16 (unsigned long x) +{ + /* add up 32-bit words for 33 bits */ + x = (x & 0xffffffff) + (x >> 32); + /* add up 16-bit and 17-bit words for 17+c bits */ + x = (x & 0xffff) + (x >> 16); + /* add up 16-bit and 2-bit for 16+c bit */ + x = (x & 0xffff) + (x >> 16); + /* add up carry.. */ + x = (x & 0xffff) + (x >> 16); + return x; +} + +/* + * computes the checksum of the TCP/UDP pseudo-header + * returns a 16-bit checksum, already complemented. + */ +unsigned short int +csum_tcpudp_magic (unsigned long saddr, unsigned long daddr, unsigned short len, + unsigned short proto, unsigned int sum) +{ + return ~from64to16(saddr + daddr + sum + ((unsigned long) ntohs(len) << 16) + + ((unsigned long) proto << 8)); +} + +EXPORT_SYMBOL(csum_tcpudp_magic); + +unsigned int +csum_tcpudp_nofold (unsigned long saddr, unsigned long daddr, unsigned short len, + unsigned short proto, unsigned int sum) +{ + unsigned long result; + + result = (saddr + daddr + sum + + ((unsigned long) ntohs(len) << 16) + + ((unsigned long) proto << 8)); + + /* Fold down to 32-bits so we don't lose in the typedef-less network stack. */ + /* 64 to 33 */ + result = (result & 0xffffffff) + (result >> 32); + /* 33 to 32 */ + result = (result & 0xffffffff) + (result >> 32); + return result; +} + +extern unsigned long do_csum (const unsigned char *, long); + +/* + * 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 + */ +unsigned int +csum_partial (const unsigned char * buff, int len, unsigned int sum) +{ + unsigned long result = do_csum(buff, len); + + /* add in old sum, and carry.. */ + result += sum; + /* 32+c bits -> 32 bits */ + result = (result & 0xffffffff) + (result >> 32); + return result; +} + +EXPORT_SYMBOL(csum_partial); + +/* + * this routine is used for miscellaneous IP-like checksums, mainly + * in icmp.c + */ +unsigned short +ip_compute_csum (unsigned char * buff, int len) +{ + return ~do_csum(buff,len); +} + +EXPORT_SYMBOL(ip_compute_csum); -- cgit v1.2.1