[apple/xnu.git] / bsd / ufs / ffs / ffs_tables.c

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
 * Copyright (c) 1982, 1986, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)ffs_tables.c	8.1 (Berkeley) 6/11/93
 */

#include <sys/param.h>

/*
 * Bit patterns for identifying fragments in the block map
 * used as ((map & around) == inside)
 */
int around[9] = {
	0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f, 0xff, 0x1ff, 0x3ff
};
int inside[9] = {
	0x0, 0x2, 0x6, 0xe, 0x1e, 0x3e, 0x7e, 0xfe, 0x1fe
};

/*
 * Given a block map bit pattern, the frag tables tell whether a
 * particular size fragment is available. 
 *
 * used as:
 * if ((1 << (size - 1)) & fragtbl[fs->fs_frag][map] {
 *	at least one fragment of the indicated size is available
 * }
 *
 * These tables are used by the scanc instruction on the VAX to
 * quickly find an appropriate fragment.
 */
u_char fragtbl124[256] = {
	0x00, 0x16, 0x16, 0x2a, 0x16, 0x16, 0x26, 0x4e,
	0x16, 0x16, 0x16, 0x3e, 0x2a, 0x3e, 0x4e, 0x8a,
	0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
	0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
	0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
	0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
	0x2a, 0x3e, 0x3e, 0x2a, 0x3e, 0x3e, 0x2e, 0x6e,
	0x3e, 0x3e, 0x3e, 0x3e, 0x2a, 0x3e, 0x6e, 0xaa,
	0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
	0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
	0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
	0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
	0x26, 0x36, 0x36, 0x2e, 0x36, 0x36, 0x26, 0x6e,
	0x36, 0x36, 0x36, 0x3e, 0x2e, 0x3e, 0x6e, 0xae,
	0x4e, 0x5e, 0x5e, 0x6e, 0x5e, 0x5e, 0x6e, 0x4e,
	0x5e, 0x5e, 0x5e, 0x7e, 0x6e, 0x7e, 0x4e, 0xce,
	0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
	0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
	0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
	0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
	0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
	0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
	0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e,
	0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e, 0xbe,
	0x2a, 0x3e, 0x3e, 0x2a, 0x3e, 0x3e, 0x2e, 0x6e,
	0x3e, 0x3e, 0x3e, 0x3e, 0x2a, 0x3e, 0x6e, 0xaa,
	0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e,
	0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e, 0xbe,
	0x4e, 0x5e, 0x5e, 0x6e, 0x5e, 0x5e, 0x6e, 0x4e,
	0x5e, 0x5e, 0x5e, 0x7e, 0x6e, 0x7e, 0x4e, 0xce,
	0x8a, 0x9e, 0x9e, 0xaa, 0x9e, 0x9e, 0xae, 0xce,
	0x9e, 0x9e, 0x9e, 0xbe, 0xaa, 0xbe, 0xce, 0x8a,
};

u_char fragtbl8[256] = {
	0x00, 0x01, 0x01, 0x02, 0x01, 0x01, 0x02, 0x04,
	0x01, 0x01, 0x01, 0x03, 0x02, 0x03, 0x04, 0x08,
	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
	0x02, 0x03, 0x03, 0x02, 0x04, 0x05, 0x08, 0x10,
	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
	0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06,
	0x04, 0x05, 0x05, 0x06, 0x08, 0x09, 0x10, 0x20,
	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
	0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
	0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06,
	0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0a,
	0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04,
	0x08, 0x09, 0x09, 0x0a, 0x10, 0x11, 0x20, 0x40,
	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
	0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
	0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
	0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
	0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07,
	0x05, 0x05, 0x05, 0x07, 0x09, 0x09, 0x11, 0x21,
	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06,
	0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0a,
	0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07,
	0x02, 0x03, 0x03, 0x02, 0x06, 0x07, 0x0a, 0x12,
	0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04,
	0x05, 0x05, 0x05, 0x07, 0x06, 0x07, 0x04, 0x0c,
	0x08, 0x09, 0x09, 0x0a, 0x09, 0x09, 0x0a, 0x0c,
	0x10, 0x11, 0x11, 0x12, 0x20, 0x21, 0x40, 0x80,
};

/*
 * The actual fragtbl array.
 */
u_char *fragtbl[MAXFRAG + 1] = {
	0, fragtbl124, fragtbl124, 0, fragtbl124, 0, 0, 0, fragtbl8,
};
Commit	Line	Data
1c79356b	1	/*
5d5c5d0d A	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
5d5c5d0d A	3	*
8f6c56a5	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
1c79356b	5	*
8f6c56a5 A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
	14	*
	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
8ad349bb	24	* limitations under the License.
8f6c56a5 A	25	*
8f6c56a5 A	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
1c79356b A	27	*/
	28	/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
	29	/*
	30	* Copyright (c) 1982, 1986, 1993
	31	* The Regents of the University of California. All rights reserved.
	32	*
	33	* Redistribution and use in source and binary forms, with or without
	34	* modification, are permitted provided that the following conditions
	35	* are met:
	36	* 1. Redistributions of source code must retain the above copyright
	37	* notice, this list of conditions and the following disclaimer.
	38	* 2. Redistributions in binary form must reproduce the above copyright
	39	* notice, this list of conditions and the following disclaimer in the
	40	* documentation and/or other materials provided with the distribution.
	41	* 3. All advertising materials mentioning features or use of this software
	42	* must display the following acknowledgement:
	43	* This product includes software developed by the University of
	44	* California, Berkeley and its contributors.
	45	* 4. Neither the name of the University nor the names of its contributors
	46	* may be used to endorse or promote products derived from this software
	47	* without specific prior written permission.
	48	*
	49	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	50	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	51	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	52	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	53	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	54	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	55	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	56	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	57	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	58	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	59	* SUCH DAMAGE.
	60	*
	61	* @(#)ffs_tables.c 8.1 (Berkeley) 6/11/93
	62	*/
	63
	64	#include <sys/param.h>
	65
	66	/*
	67	* Bit patterns for identifying fragments in the block map
	68	* used as ((map & around) == inside)
	69	*/
	70	int around[9] = {
	71	0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f, 0xff, 0x1ff, 0x3ff
	72	};
	73	int inside[9] = {
	74	0x0, 0x2, 0x6, 0xe, 0x1e, 0x3e, 0x7e, 0xfe, 0x1fe
	75	};
	76
	77	/*
	78	* Given a block map bit pattern, the frag tables tell whether a
	79	* particular size fragment is available.
	80	*
	81	* used as:
	82	* if ((1 << (size - 1)) & fragtbl[fs->fs_frag][map] {
	83	* at least one fragment of the indicated size is available
	84	* }
	85	*
	86	* These tables are used by the scanc instruction on the VAX to
	87	* quickly find an appropriate fragment.
	88	*/
	89	u_char fragtbl124[256] = {
	90	0x00, 0x16, 0x16, 0x2a, 0x16, 0x16, 0x26, 0x4e,
91	0x16, 0x16, 0x16, 0x3e, 0x2a, 0x3e, 0x4e, 0x8a,
92	0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
93	0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
94	0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
95	0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
96	0x2a, 0x3e, 0x3e, 0x2a, 0x3e, 0x3e, 0x2e, 0x6e,
97	0x3e, 0x3e, 0x3e, 0x3e, 0x2a, 0x3e, 0x6e, 0xaa,
98	0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
99	0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
100	0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
101	0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
102	0x26, 0x36, 0x36, 0x2e, 0x36, 0x36, 0x26, 0x6e,
103	0x36, 0x36, 0x36, 0x3e, 0x2e, 0x3e, 0x6e, 0xae,
104	0x4e, 0x5e, 0x5e, 0x6e, 0x5e, 0x5e, 0x6e, 0x4e,
105	0x5e, 0x5e, 0x5e, 0x7e, 0x6e, 0x7e, 0x4e, 0xce,
106	0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
107	0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
108	0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
109	0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
110	0x16, 0x16, 0x16, 0x3e, 0x16, 0x16, 0x36, 0x5e,
111	0x16, 0x16, 0x16, 0x3e, 0x3e, 0x3e, 0x5e, 0x9e,
112	0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e,
113	0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e, 0xbe,
114	0x2a, 0x3e, 0x3e, 0x2a, 0x3e, 0x3e, 0x2e, 0x6e,
115	0x3e, 0x3e, 0x3e, 0x3e, 0x2a, 0x3e, 0x6e, 0xaa,
116	0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e,
117	0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x3e, 0x7e, 0xbe,
118	0x4e, 0x5e, 0x5e, 0x6e, 0x5e, 0x5e, 0x6e, 0x4e,
119	0x5e, 0x5e, 0x5e, 0x7e, 0x6e, 0x7e, 0x4e, 0xce,
120	0x8a, 0x9e, 0x9e, 0xaa, 0x9e, 0x9e, 0xae, 0xce,
121	0x9e, 0x9e, 0x9e, 0xbe, 0xaa, 0xbe, 0xce, 0x8a,
122	};
123
124	u_char fragtbl8[256] = {
125	0x00, 0x01, 0x01, 0x02, 0x01, 0x01, 0x02, 0x04,
126	0x01, 0x01, 0x01, 0x03, 0x02, 0x03, 0x04, 0x08,
127	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
128	0x02, 0x03, 0x03, 0x02, 0x04, 0x05, 0x08, 0x10,
129	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
130	0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
131	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06,
132	0x04, 0x05, 0x05, 0x06, 0x08, 0x09, 0x10, 0x20,
133	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
134	0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
135	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
136	0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
137	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06,
138	0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0a,
139	0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04,
140	0x08, 0x09, 0x09, 0x0a, 0x10, 0x11, 0x20, 0x40,
141	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
142	0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
143	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
144	0x03, 0x03, 0x03, 0x03, 0x05, 0x05, 0x09, 0x11,
145	0x01, 0x01, 0x01, 0x03, 0x01, 0x01, 0x03, 0x05,
146	0x01, 0x01, 0x01, 0x03, 0x03, 0x03, 0x05, 0x09,
147	0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07,
148	0x05, 0x05, 0x05, 0x07, 0x09, 0x09, 0x11, 0x21,
149	0x02, 0x03, 0x03, 0x02, 0x03, 0x03, 0x02, 0x06,
150	0x03, 0x03, 0x03, 0x03, 0x02, 0x03, 0x06, 0x0a,
151	0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x07,
152	0x02, 0x03, 0x03, 0x02, 0x06, 0x07, 0x0a, 0x12,
153	0x04, 0x05, 0x05, 0x06, 0x05, 0x05, 0x06, 0x04,
154	0x05, 0x05, 0x05, 0x07, 0x06, 0x07, 0x04, 0x0c,
155	0x08, 0x09, 0x09, 0x0a, 0x09, 0x09, 0x0a, 0x0c,
156	0x10, 0x11, 0x11, 0x12, 0x20, 0x21, 0x40, 0x80,
157	};
158
159	/*
160	* The actual fragtbl array.
161	*/
162	u_char *fragtbl[MAXFRAG + 1] = {
163	0, fragtbl124, fragtbl124, 0, fragtbl124, 0, 0, 0, fragtbl8,
164	};