param.h revision 974
1/*-
2 * Copyright (c) 1990 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * William Jolitz.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by the University of
19 *	California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 *	from: @(#)param.h	5.8 (Berkeley) 6/28/91
37 *	$Id: param.h,v 1.11 1993/12/19 00:50:17 wollman Exp $
38 */
39
40#ifndef _MACHINE_PARAM_H_
41#define _MACHINE_PARAM_H_ 1
42
43/*
44 * Machine dependent constants for Intel 386.
45 */
46
47#define MACHINE		"i386"
48#define MID_MACHINE	MID_I386
49
50/*
51 * Round p (pointer or byte index) up to a correctly-aligned value
52 * for all data types (int, long, ...).   The result is u_int and
53 * must be cast to any desired pointer type.
54 */
55#define ALIGNBYTES	(sizeof(int) - 1)
56#define ALIGN(p)	(((u_int)(p) + ALIGNBYTES) &~ ALIGNBYTES)
57
58/* XXX PGSHIFT and PG_SHIFT are two names for the same thing */
59#define PGSHIFT		12		/* LOG2(NBPG) */
60#define NBPG		(1 << PGSHIFT)	/* bytes/page */
61#define PGOFSET		(NBPG-1)	/* byte offset into page */
62#define NPTEPG		(NBPG/(sizeof (struct pte)))
63
64/* XXX PDRSHIFT and PD_SHIFT are two names for the same thing */
65#define PDRSHIFT	22		/* LOG2(NBPDR) */
66#define NBPDR		(1 << PDRSHIFT)	/* bytes/page dir */
67#define PDROFSET	(NBPDR-1)	/* byte offset into page dir */
68
69/*
70 * XXX This should really be KPTDPTDI << PDRSHIFT, but since KPTDPTDI is
71 * defined in pmap.h which is included after this we can't do that
72 * (YET!)
73 */
74#define BTOPKERNBASE	(KERNBASE >> PGSHIFT)
75
76#define DEV_BSHIFT	9		/* log2(DEV_BSIZE) */
77#define DEV_BSIZE	(1 << DEV_BSHIFT)
78
79#define BLKDEV_IOSIZE	2048
80#define MAXPHYS		(64 * 1024)	/* max raw I/O transfer size */
81
82#define CLSIZELOG2	0
83#define CLSIZE		(1 << CLSIZELOG2)
84
85/* NOTE: SSIZE, SINCR and UPAGES must be multiples of CLSIZE */
86#define SSIZE	1		/* initial stack size/NBPG */
87#define SINCR	1		/* increment of stack/NBPG */
88
89#define UPAGES	2		/* pages of u-area */
90
91/*
92 * Constants related to network buffer management.
93 * MCLBYTES must be no larger than CLBYTES (the software page size), and,
94 * on machines that exchange pages of input or output buffers with mbuf
95 * clusters (MAPPED_MBUFS), MCLBYTES must also be an integral multiple
96 * of the hardware page size.
97 */
98#ifndef	MSIZE
99#define MSIZE		128		/* size of an mbuf */
100#endif	/* MSIZE */
101
102#ifndef	MCLSHIFT
103#define MCLSHIFT	11		/* convert bytes to m_buf clusters */
104#endif	/* MCLSHIFT */
105#define MCLBYTES	(1 << MCLSHIFT)	/* size of an m_buf cluster */
106#define MCLOFSET	(MCLBYTES - 1)	/* offset within an m_buf cluster */
107
108#ifndef NMBCLUSTERS
109#ifdef GATEWAY
110#define NMBCLUSTERS	512		/* map size, max cluster allocation */
111#else
112#define NMBCLUSTERS	256		/* map size, max cluster allocation */
113#endif	/* GATEWAY */
114#endif	/* NMBCLUSTERS */
115
116/*
117 * Some macros for units conversion
118 */
119/* Core clicks (4096 bytes) to segments and vice versa */
120#define ctos(x)	(x)
121#define stoc(x)	(x)
122
123/* Core clicks (4096 bytes) to disk blocks */
124#define ctod(x)	((x)<<(PGSHIFT-DEV_BSHIFT))
125#define dtoc(x)	((x)>>(PGSHIFT-DEV_BSHIFT))
126#define dtob(x)	((x)<<DEV_BSHIFT)
127
128/* clicks to bytes */
129#define ctob(x)	((x)<<PGSHIFT)
130
131/* bytes to clicks */
132#define btoc(x)	(((unsigned)(x)+(NBPG-1))>>PGSHIFT)
133
134#define btodb(bytes)	 		/* calculates (bytes / DEV_BSIZE) */ \
135	((unsigned)(bytes) >> DEV_BSHIFT)
136#define dbtob(db)			/* calculates (db * DEV_BSIZE) */ \
137	((unsigned)(db) << DEV_BSHIFT)
138
139/*
140 * Map a ``block device block'' to a file system block.
141 * This should be device dependent, and will be if we
142 * add an entry to cdevsw/bdevsw for that purpose.
143 * For now though just use DEV_BSIZE.
144 */
145#define bdbtofsb(bn)	((bn) / (BLKDEV_IOSIZE/DEV_BSIZE))
146
147/*
148 * Mach derived conversion macros
149 */
150#define i386_round_pdr(x)	((((unsigned)(x)) + NBPDR - 1) & ~(NBPDR-1))
151#define i386_trunc_pdr(x)	((unsigned)(x) & ~(NBPDR-1))
152#define i386_round_page(x)	((((unsigned)(x)) + NBPG - 1) & ~(NBPG-1))
153#define i386_trunc_page(x)	((unsigned)(x) & ~(NBPG-1))
154#define i386_btod(x)		((unsigned)(x) >> PDRSHIFT)
155#define i386_dtob(x)		((unsigned)(x) << PDRSHIFT)
156#define i386_btop(x)		((unsigned)(x) >> PGSHIFT)
157#define i386_ptob(x)		((unsigned)(x) << PGSHIFT)
158
159#endif /* _MACHINE_PARAM_H_ */
160