zfs/lib/libzpool/fletcher.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 #pragma ident   "@(#)fletcher.c 1.2     06/03/03 SMI"
  27
  28 #include <sys/types.h>
  29 #include <sys/sysmacros.h>
  30 #include <sys/byteorder.h>
  31 #include <sys/spa.h>
  32
  33 void
  34 fletcher_2_native(const void *buf, uint64_t size, zio_cksum_t *zcp)
  35 {
  36         const uint64_t *ip = buf;
  37         const uint64_t *ipend = ip + (size / sizeof (uint64_t));
  38         uint64_t a0, b0, a1, b1;
  39
  40         for (a0 = b0 = a1 = b1 = 0; ip < ipend; ip += 2) {
  41                 a0 += ip[0];
  42                 a1 += ip[1];
  43                 b0 += a0;
  44                 b1 += a1;
  45         }
  46
  47         ZIO_SET_CHECKSUM(zcp, a0, a1, b0, b1);
  48 }
  49
  50 void
  51 fletcher_2_byteswap(const void *buf, uint64_t size, zio_cksum_t *zcp)
  52 {
  53         const uint64_t *ip = buf;
  54         const uint64_t *ipend = ip + (size / sizeof (uint64_t));
  55         uint64_t a0, b0, a1, b1;
  56
  57         for (a0 = b0 = a1 = b1 = 0; ip < ipend; ip += 2) {
  58                 a0 += BSWAP_64(ip[0]);
  59                 a1 += BSWAP_64(ip[1]);
  60                 b0 += a0;
  61                 b1 += a1;
  62         }
  63
  64         ZIO_SET_CHECKSUM(zcp, a0, a1, b0, b1);
  65 }
  66
  67 void
  68 fletcher_4_native(const void *buf, uint64_t size, zio_cksum_t *zcp)
  69 {
  70         const uint32_t *ip = buf;
  71         const uint32_t *ipend = ip + (size / sizeof (uint32_t));
  72         uint64_t a, b, c, d;
  73
  74         for (a = b = c = d = 0; ip < ipend; ip++) {
  75                 a += ip[0];
  76                 b += a;
  77                 c += b;
  78                 d += c;
  79         }
  80
  81         ZIO_SET_CHECKSUM(zcp, a, b, c, d);
  82 }
  83
  84 void
  85 fletcher_4_byteswap(const void *buf, uint64_t size, zio_cksum_t *zcp)
  86 {
  87         const uint32_t *ip = buf;
  88         const uint32_t *ipend = ip + (size / sizeof (uint32_t));
  89         uint64_t a, b, c, d;
  90
  91         for (a = b = c = d = 0; ip < ipend; ip++) {
  92                 a += BSWAP_32(ip[0]);
  93                 b += a;
  94                 c += b;
  95                 d += c;
  96         }
  97
  98         ZIO_SET_CHECKSUM(zcp, a, b, c, d);
  99 }
 100
 101 void
 102 fletcher_4_incremental_native(const void *buf, uint64_t size,
 103     zio_cksum_t *zcp)
 104 {
 105         const uint32_t *ip = buf;
 106         const uint32_t *ipend = ip + (size / sizeof (uint32_t));
 107         uint64_t a, b, c, d;
 108
 109         a = zcp->zc_word[0];
 110         b = zcp->zc_word[1];
 111         c = zcp->zc_word[2];
 112         d = zcp->zc_word[3];
 113
 114         for (; ip < ipend; ip++) {
 115                 a += ip[0];
 116                 b += a;
 117                 c += b;
 118                 d += c;
 119         }
 120
 121         ZIO_SET_CHECKSUM(zcp, a, b, c, d);
 122 }
 123
 124 void
 125 fletcher_4_incremental_byteswap(const void *buf, uint64_t size,
 126     zio_cksum_t *zcp)
 127 {
 128         const uint32_t *ip = buf;
 129         const uint32_t *ipend = ip + (size / sizeof (uint32_t));
 130         uint64_t a, b, c, d;
 131
 132         a = zcp->zc_word[0];
 133         b = zcp->zc_word[1];
 134         c = zcp->zc_word[2];
 135         d = zcp->zc_word[3];
 136
 137         for (; ip < ipend; ip++) {
 138                 a += BSWAP_32(ip[0]);
 139                 b += a;
 140                 c += b;
 141                 d += c;
 142         }
 143
 144         ZIO_SET_CHECKSUM(zcp, a, b, c, d);
 145 }