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