#ifndef __ASM_SH_CHECKSUM_H #define __ASM_SH_CHECKSUM_H /* * 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) 1999 by Kaz Kojima & Niibe Yutaka */ #include <linux/in6.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 */ asmlinkage __wsum csum_partial(const void *buff, int len, __wsum sum); /* * the same as csum_partial, but copies from src while it * checksums, and handles user-space pointer exceptions correctly, when needed. * * here even more important to align src and dst on a 32-bit (or even * better 64-bit) boundary */ asmlinkage __wsum csum_partial_copy_generic(const void *src, void *dst, int len, __wsum sum, int *src_err_ptr, int *dst_err_ptr); /* * Note: when you get a NULL pointer exception here this means someone * passed in an incorrect kernel address to one of these functions. * * If you use these functions directly please don't forget the * access_ok(). */ static inline __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum) { return csum_partial_copy_generic(src, dst, len, sum, NULL, NULL); } static inline __wsum csum_partial_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *err_ptr) { return csum_partial_copy_generic((__force const void *)src, dst, len, sum, err_ptr, NULL); } /* * Fold a partial checksum */ static inline __sum16 csum_fold(__wsum sum) { unsigned int __dummy; __asm__("swap.w %0, %1\n\t" "extu.w %0, %0\n\t" "extu.w %1, %1\n\t" "add %1, %0\n\t" "swap.w %0, %1\n\t" "add %1, %0\n\t" "not %0, %0\n\t" : "=r" (sum), "=&r" (__dummy) : "0" (sum) : "t"); return (__force __sum16)sum; } /* * This is a version of ip_compute_csum() optimized for IP headers, * which always checksum on 4 octet boundaries. * * i386 version 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) { unsigned int sum, __dummy0, __dummy1; __asm__ __volatile__( "mov.l @%1+, %0\n\t" "mov.l @%1+, %3\n\t" "add #-2, %2\n\t" "clrt\n\t" "1:\t" "addc %3, %0\n\t" "movt %4\n\t" "mov.l @%1+, %3\n\t" "dt %2\n\t" "bf/s 1b\n\t" " cmp/eq #1, %4\n\t" "addc %3, %0\n\t" "addc %2, %0" /* Here %2 is 0, add carry-bit */ /* Since the input registers which are loaded with iph and ihl are modified, we must also specify them as outputs, or gcc will assume they contain their original values. */ : "=r" (sum), "=r" (iph), "=r" (ihl), "=&r" (__dummy0), "=&z" (__dummy1) : "1" (iph), "2" (ihl) : "t"); return csum_fold(sum); } static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len, unsigned short proto, __wsum sum) { #ifdef __LITTLE_ENDIAN__ unsigned long len_proto = (proto + len) << 8; #else unsigned long len_proto = proto + len; #endif __asm__("clrt\n\t" "addc %0, %1\n\t" "addc %2, %1\n\t" "addc %3, %1\n\t" "movt %0\n\t" "add %1, %0" : "=r" (sum), "=r" (len_proto) : "r" (daddr), "r" (saddr), "1" (len_proto), "0" (sum) : "t"); 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) { unsigned int __dummy; __asm__("clrt\n\t" "mov.l @(0,%2), %1\n\t" "addc %1, %0\n\t" "mov.l @(4,%2), %1\n\t" "addc %1, %0\n\t" "mov.l @(8,%2), %1\n\t" "addc %1, %0\n\t" "mov.l @(12,%2), %1\n\t" "addc %1, %0\n\t" "mov.l @(0,%3), %1\n\t" "addc %1, %0\n\t" "mov.l @(4,%3), %1\n\t" "addc %1, %0\n\t" "mov.l @(8,%3), %1\n\t" "addc %1, %0\n\t" "mov.l @(12,%3), %1\n\t" "addc %1, %0\n\t" "addc %4, %0\n\t" "addc %5, %0\n\t" "movt %1\n\t" "add %1, %0\n" : "=r" (sum), "=&r" (__dummy) : "r" (saddr), "r" (daddr), "r" (htonl(len)), "r" (htonl(proto)), "0" (sum) : "t"); return csum_fold(sum); } /* * 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) { if (access_ok(VERIFY_WRITE, dst, len)) return csum_partial_copy_generic((__force const void *)src, dst, len, sum, NULL, err_ptr); if (len) *err_ptr = -EFAULT; return (__force __wsum)-1; /* invalid checksum */ } #endif /* __ASM_SH_CHECKSUM_H */