1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 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 __FBSDID("$FreeBSD$"); 36 37 #include <sys/param.h> 38 #include <sys/types.h> 39 #include <ufs/ufs/dinode.h> 40 #include <ufs/ffs/fs.h> 41 42 /* 43 * Bit patterns for identifying fragments in the block map 44 * used as ((map & around) == inside) 45 */ 46 int around[9] = { 47 0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f, 0xff, 0x1ff, 0x3ff 48 }; 49 int inside[9] = { 50 0x0, 0x2, 0x6, 0xe, 0x1e, 0x3e, 0x7e, 0xfe, 0x1fe 51 }; 52 53 /* 54 * Given a block map bit pattern, the frag tables tell whether a 55 * particular size fragment is available. 56 * 57 * used as: 58 * if ((1 << (size - 1)) & fragtbl[fs->fs_frag][map] { 59 * at least one fragment of the indicated size is available 60 * } 61 * 62 * These tables are used by the scanc instruction on the VAX to 63 * quickly find an appropriate fragment. 64 */ 65 static u_char fragtbl124[256] = { 66 0x00, 0x16, 0x16, 0x2a, 0x16, 0x16, 0x26, 0x4e, 67 0x16, 0x16, 0x16, 0x3e, 0x2a, 0x3e, 0x4e, 0x8a, 68 0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e, 69 0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e, 70 0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e, 71 0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e, 72 0x2a, 0x3e, 0x3e, 0x2a, 0x3e, 0x3e, 0x2e, 0x6e, 73 0x3e, 0x3e, 0x3e, 0x3e, 0x2a, 0x3e, 0x6e, 0xaa, 74 0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e, 75 0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e, 76 0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e, 77 0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e, 78 0x26, 0x36, 0x36, 0x2e, 0x36, 0x36, 0x26, 0x6e, 79 0x36, 0x36, 0x36, 0x3e, 0x2e, 0x3e, 0x6e, 0xae, 80 0x4e, 0x5e, 0x5e, 0x6e, 0x5e, 0x5e, 0x6e, 0x4e, 81 0x5e, 0x5e, 0x5e, 0x7e, 0x6e, 0x7e, 0x4e, 0xce, 82 0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e, 83 0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e, 84 0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e, 85 0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e, 86 0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e, 87 0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e, 88 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e, 89 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e, 0xbe, 90 0x2a, 0x3e, 0x3e, 0x2a, 0x3e, 0x3e, 0x2e, 0x6e, 91 0x3e, 0x3e, 0x3e, 0x3e, 0x2a, 0x3e, 0x6e, 0xaa, 92 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e, 93 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e, 0xbe, 94 0x4e, 0x5e, 0x5e, 0x6e, 0x5e, 0x5e, 0x6e, 0x4e, 95 0x5e, 0x5e, 0x5e, 0x7e, 0x6e, 0x7e, 0x4e, 0xce, 96 0x8a, 0x9e, 0x9e, 0xaa, 0x9e, 0x9e, 0xae, 0xce, 97 0x9e, 0x9e, 0x9e, 0xbe, 0xaa, 0xbe, 0xce, 0x8a, 98 }; 99 100 static u_char fragtbl8[256] = { 101 0x00, 0x01, 0x01, 0x02, 0x01, 0x01, 0x02, 0x04, 102 0x01, 0x01, 0x01, 0x03, 0x02, 0x03, 0x04, 0x08, 103 0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 104 0x02, 0x03, 0x03, 0x02, 0x04, 0x05, 0x08, 0x10, 105 0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 106 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09, 107 0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 108 0x04, 0x05, 0x05, 0x06, 0x08, 0x09, 0x10, 0x20, 109 0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 110 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09, 111 0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 112 0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11, 113 0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 114 0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0a, 115 0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04, 116 0x08, 0x09, 0x09, 0x0a, 0x10, 0x11, 0x20, 0x40, 117 0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 118 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09, 119 0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 120 0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11, 121 0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05, 122 0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09, 123 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07, 124 0x05, 0x05, 0x05, 0x07, 0x09, 0x09, 0x11, 0x21, 125 0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06, 126 0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0a, 127 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07, 128 0x02, 0x03, 0x03, 0x02, 0x06, 0x07, 0x0a, 0x12, 129 0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04, 130 0x05, 0x05, 0x05, 0x07, 0x06, 0x07, 0x04, 0x0c, 131 0x08, 0x09, 0x09, 0x0a, 0x09, 0x09, 0x0a, 0x0c, 132 0x10, 0x11, 0x11, 0x12, 0x20, 0x21, 0x40, 0x80, 133 }; 134 135 /* 136 * The actual fragtbl array. 137 */ 138 u_char *fragtbl[MAXFRAG + 1] = { 139 0, fragtbl124, fragtbl124, 0, fragtbl124, 0, 0, 0, fragtbl8, 140 }; 141