#include /*- * Copyright (c) 1990 The Regents of the University of California. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /*- * Copyright (c) 2001 by Thomas Moestl . * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * from tahoe: in_cksum.c 1.2 86/01/05 * from: @(#)in_cksum.c 1.3 (Berkeley) 1/19/91 * from: FreeBSD: src/sys/i386/i386/in_cksum.c,v 1.22 2000/11/25 */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include /* * Checksum routine for Internet Protocol family headers. * * This routine is very heavily used in the network * code and should be modified for each CPU to be as fast as possible. * * This implementation is a sparc64 version. Most code was taken over * and adapted from the i386. Some optimizations were changed to achieve * (hopefully) better performance. * This uses 64-bit loads, but 32-bit additions due to the lack of a 64-bit * add-with-carry operation. */ /* * REDUCE() is actually not used that frequently... maybe a C implementation * would suffice. */ #define REDUCE(sum, tmp) __asm( \ "sll %2, 16, %1\n" \ "addcc %2, %1, %0\n" \ "srl %0, 16, %0\n" \ "addc %0, 0, %0" : "=r" (sum), "=&r" (tmp) : "0" (sum) : "cc") /* * Note that some of these macros depend on the flags being preserved * between calls, thus they have to be used within a single __asm(). */ #define LD64_ADD32(n, mod) \ "ldx [%3 + " #n "], %1\n" \ "add" #mod " %2, %1, %0\n" \ "srlx %1, 32, %1\n" \ "addccc %0, %1, %0\n" #define LD32_ADD32(n, mod) \ "lduw [%3 + " #n "], %1\n" \ "add" #mod " %2, %1, %0\n" #define MOP(sum, tmp, addr) \ "addc %2, 0, %0" \ : "=r" (sum), "=&r" (tmp) : "0" (sum), "r" (addr) : "cc" u_short in_cksum_skip(struct mbuf *m, int len, int skip) { u_short *w; unsigned long tmp, sum = 0; int mlen = 0; int byte_swapped = 0; u_short su = 0; len -= skip; for (; skip > 0 && m != NULL; m = m->m_next) { if (m->m_len > skip) { mlen = m->m_len - skip; w = (u_short *)(mtod(m, u_char *) + skip); goto skip_start; } else skip -= m->m_len; } for (; m != NULL && len > 0; m = m->m_next) { if (m->m_len == 0) continue; w = mtod(m, u_short *); if (mlen == -1) { /* * The first byte of this mbuf is the continuation * of a word spanning between this mbuf and the * last mbuf. * * The high order byte of su is already saved when * scanning previous mbuf. sum was REDUCEd when we * found mlen == -1 */ sum += su | *(u_char *)w; w = (u_short *)((u_char *)w + 1); mlen = m->m_len - 1; len--; } else mlen = m->m_len; skip_start: if (len < mlen) mlen = len; len -= mlen; /* * Force to a 8-byte boundary first so that we can use * LD64_ADD32. */ if (((u_long)w & 7) != 0) { REDUCE(sum, tmp); if (((u_long)w & 1) != 0 && mlen >= 1) { sum <<= 8; su = *(u_char *)w << 8; w = (u_short *)((u_char *)w + 1); mlen--; byte_swapped = 1; } if (((u_long)w & 2) != 0 && mlen >= 2) { sum += *w++; mlen -= 2; } if (((u_long)w & 4) != 0 && mlen >= 4) { __asm( LD32_ADD32(0, cc) MOP(sum, tmp, w) ); w += 2; mlen -= 4; } } /* * Do as much of the checksum as possible 64 bits at at time. * In fact, this loop is unrolled to make overhead from * branches &c small. */ for (; mlen >= 64; mlen -= 64) { __asm( LD64_ADD32(0, cc) LD64_ADD32(8, ccc) LD64_ADD32(16, ccc) LD64_ADD32(24, ccc) LD64_ADD32(32, ccc) LD64_ADD32(40, ccc) LD64_ADD32(48, ccc) LD64_ADD32(56, ccc) MOP(sum, tmp, w) ); w += 32; } if (mlen >= 32) { __asm( LD64_ADD32(0, cc) LD64_ADD32(8, ccc) LD64_ADD32(16, ccc) LD64_ADD32(24, ccc) MOP(sum, tmp, w) ); w += 16; mlen -= 32; } if (mlen >= 16) { __asm( LD64_ADD32(0, cc) LD64_ADD32(8, ccc) MOP(sum, tmp, w) ); w += 8; mlen -= 16; } if (mlen >= 8) { __asm( LD64_ADD32(0, cc) MOP(sum, tmp, w) ); w += 4; mlen -= 8; } REDUCE(sum, tmp); while ((mlen -= 2) >= 0) sum += *w++; if (byte_swapped) { sum <<= 8; byte_swapped = 0; if (mlen == -1) { su |= *(u_char *)w; sum += su; mlen = 0; } else mlen = -1; } else if (mlen == -1) { /* * This mbuf has odd number of bytes. * There could be a word split between * this mbuf and the next mbuf. * Save the last byte (to prepend to next mbuf). */ su = *(u_char *)w << 8; } } if (len) printf("%s: out of data by %d\n", __func__, len); if (mlen == -1) { /* * The last mbuf has odd # of bytes. Follow the * standard (the odd byte is shifted left by 8 bits). */ sum += su & 0xff00; } REDUCE(sum, tmp); return (~sum & 0xffff); }