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 */
46int around[9] = {
47	0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f, 0xff, 0x1ff, 0x3ff
48};
49int 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 */
65static 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
100static 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 */
138u_char *fragtbl[MAXFRAG + 1] = {
139	0, fragtbl124, fragtbl124, 0, fragtbl124, 0, 0, 0, fragtbl8,
140};
141