ffs_tables.c revision 1.6
1 /* $NetBSD: ffs_tables.c,v 1.6 2003/08/07 16:34:31 agc Exp $ */ 2 3 /* 4 * Copyright (c) 1982, 1986, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)ffs_tables.c 8.1 (Berkeley) 6/11/93 32 */ 33 34 #include <sys/cdefs.h> 35 #if defined(__KERNEL_RCSID) 36 __KERNEL_RCSID(0, "$NetBSD: ffs_tables.c,v 1.6 2003/08/07 16:34:31 agc Exp $"); 37 #endif 38 39 #if HAVE_CONFIG_H 40 #include "config.h" 41 #endif 42 43 #include <sys/param.h> 44 45 /* 46 * Bit patterns for identifying fragments in the block map 47 * used as ((map & around) == inside) 48 */ 49 const int around[9] = { 50 0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f, 0xff, 0x1ff, 0x3ff 51 }; 52 const int inside[9] = { 53 0x0, 0x2, 0x6, 0xe, 0x1e, 0x3e, 0x7e, 0xfe, 0x1fe 54 }; 55 56 /* 57 * Given a block map bit pattern, the frag tables tell whether a 58 * particular size fragment is available. 59 * 60 * used as: 61 * if ((1 << (size - 1)) & fragtbl[fs->fs_frag][map] { 62 * at least one fragment of the indicated size is available 63 * } 64 * 65 * These tables are used by the scanc instruction on the VAX to 66 * quickly find an appropriate fragment. 67 */ 68 const u_char fragtbl124[256] = { 69 0x00, 0x16, 0x16, 0x2a, 0x16, 0x16, 0x26, 0x4e, 70 0x16, 0x16, 0x16, 0x3e, 0x2a, 0x3e, 0x4e, 0x8a, 71 0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e, 72 0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e, 73 0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e, 74 0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e, 75 0x2a, 0x3e, 0x3e, 0x2a, 0x3e, 0x3e, 0x2e, 0x6e, 76 0x3e, 0x3e, 0x3e, 0x3e, 0x2a, 0x3e, 0x6e, 0xaa, 77 0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e, 78 0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e, 79 0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e, 80 0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e, 81 0x26, 0x36, 0x36, 0x2e, 0x36, 0x36, 0x26, 0x6e, 82 0x36, 0x36, 0x36, 0x3e, 0x2e, 0x3e, 0x6e, 0xae, 83 0x4e, 0x5e, 0x5e, 0x6e, 0x5e, 0x5e, 0x6e, 0x4e, 84 0x5e, 0x5e, 0x5e, 0x7e, 0x6e, 0x7e, 0x4e, 0xce, 85 0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e, 86 0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e, 87 0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e, 88 0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e, 89 0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e, 90 0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e, 91 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e, 92 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e, 0xbe, 93 0x2a, 0x3e, 0x3e, 0x2a, 0x3e, 0x3e, 0x2e, 0x6e, 94 0x3e, 0x3e, 0x3e, 0x3e, 0x2a, 0x3e, 0x6e, 0xaa, 95 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e, 96 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e, 0xbe, 97 0x4e, 0x5e, 0x5e, 0x6e, 0x5e, 0x5e, 0x6e, 0x4e, 98 0x5e, 0x5e, 0x5e, 0x7e, 0x6e, 0x7e, 0x4e, 0xce, 99 0x8a, 0x9e, 0x9e, 0xaa, 0x9e, 0x9e, 0xae, 0xce, 100 0x9e, 0x9e, 0x9e, 0xbe, 0xaa, 0xbe, 0xce, 0x8a, 101 }; 102 103 const u_char fragtbl8[256] = { 104 0x00, 0x01, 0x01, 0x02, 0x01, 0x01, 0x02, 0x04, 105 0x01, 0x01, 0x01, 0x03, 0x02, 0x03, 0x04, 0x08, 106 0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 107 0x02, 0x03, 0x03, 0x02, 0x04, 0x05, 0x08, 0x10, 108 0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 109 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09, 110 0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 111 0x04, 0x05, 0x05, 0x06, 0x08, 0x09, 0x10, 0x20, 112 0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 113 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09, 114 0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 115 0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11, 116 0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 117 0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0a, 118 0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04, 119 0x08, 0x09, 0x09, 0x0a, 0x10, 0x11, 0x20, 0x40, 120 0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 121 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09, 122 0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 123 0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11, 124 0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 125 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09, 126 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07, 127 0x05, 0x05, 0x05, 0x07, 0x09, 0x09, 0x11, 0x21, 128 0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 129 0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0a, 130 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07, 131 0x02, 0x03, 0x03, 0x02, 0x06, 0x07, 0x0a, 0x12, 132 0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04, 133 0x05, 0x05, 0x05, 0x07, 0x06, 0x07, 0x04, 0x0c, 134 0x08, 0x09, 0x09, 0x0a, 0x09, 0x09, 0x0a, 0x0c, 135 0x10, 0x11, 0x11, 0x12, 0x20, 0x21, 0x40, 0x80, 136 }; 137 138 /* 139 * The actual fragtbl array. 140 */ 141 const u_char * const fragtbl[MAXFRAG + 1] = { 142 0, fragtbl124, fragtbl124, 0, fragtbl124, 0, 0, 0, fragtbl8, 143 }; 144
Indexes created Mon Sep 29 15:09:53 GMT 2025