param.h revision 551
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 *	$Id$
38 */
39
40/*
41 * Machine dependent constants for Intel 386.
42 */
43
44#define MACHINE		"i386"
45#define MID_MACHINE	MID_I386
46
47/*
48 * Round p (pointer or byte index) up to a correctly-aligned value
49 * for all data types (int, long, ...).   The result is u_int and
50 * must be cast to any desired pointer type.
51 */
52#define ALIGNBYTES	(sizeof(int) - 1)
53#define ALIGN(p)	(((u_int)(p) + ALIGNBYTES) &~ ALIGNBYTES)
54
55#define	NBPG		4096		/* bytes/page */
56#define	PGOFSET		(NBPG-1)	/* byte offset into page */
57#define	PGSHIFT		12		/* LOG2(NBPG) */
58#define	NPTEPG		(NBPG/(sizeof (struct pte)))
59
60#define NBPDR		(1024*NBPG)	/* bytes/page dir */
61#define	PDROFSET	(NBPDR-1)	/* byte offset into page dir */
62#define	PDRSHIFT	22		/* LOG2(NBPDR) */
63
64#define	KERNBASE	0xFE000000	/* start of kernel virtual */
65#define	BTOPKERNBASE	((u_long)KERNBASE >> PGSHIFT)
66
67#define	DEV_BSIZE	512
68#define	DEV_BSHIFT	9		/* log2(DEV_BSIZE) */
69#define BLKDEV_IOSIZE	2048
70#define	MAXPHYS		(64 * 1024)	/* max raw I/O transfer size */
71
72#define	CLSIZE		1
73#define	CLSIZELOG2	0
74
75/* NOTE: SSIZE, SINCR and UPAGES must be multiples of CLSIZE */
76#define	SSIZE	1		/* initial stack size/NBPG */
77#define	SINCR	1		/* increment of stack/NBPG */
78
79#define	UPAGES	2		/* pages of u-area */
80
81/*
82 * Constants related to network buffer management.
83 * MCLBYTES must be no larger than CLBYTES (the software page size), and,
84 * on machines that exchange pages of input or output buffers with mbuf
85 * clusters (MAPPED_MBUFS), MCLBYTES must also be an integral multiple
86 * of the hardware page size.
87 */
88#ifndef	MSIZE
89#define	MSIZE		128		/* size of an mbuf */
90#endif	/* MSIZE */
91
92#ifndef	MCLSHIFT
93#define	MCLSHIFT	11		/* convert bytes to m_buf clusters */
94#endif	/* MCLSHIFT */
95#define	MCLBYTES	(1 << MCLSHIFT)	/* size of a m_buf cluster */
96#define	MCLOFSET	(MCLBYTES - 1)	/* offset within a m_buf cluster */
97
98#ifndef NMBCLUSTERS
99#ifdef GATEWAY
100#define	NMBCLUSTERS	512		/* map size, max cluster allocation */
101#else
102#define	NMBCLUSTERS	256		/* map size, max cluster allocation */
103#endif	/* GATEWAY */
104#endif	/* NMBCLUSTERS */
105
106/*
107 * Size of kernel malloc arena in CLBYTES-sized logical pages
108 */
109#ifndef NKMEMCLUSTERS
110#define	NKMEMCLUSTERS	(3072*1024/CLBYTES)
111#endif
112/*
113 * Some macros for units conversion
114 */
115/* Core clicks (4096 bytes) to segments and vice versa */
116#define	ctos(x)	(x)
117#define	stoc(x)	(x)
118
119/* Core clicks (4096 bytes) to disk blocks */
120#define	ctod(x)	((x)<<(PGSHIFT-DEV_BSHIFT))
121#define	dtoc(x)	((x)>>(PGSHIFT-DEV_BSHIFT))
122#define	dtob(x)	((x)<<DEV_BSHIFT)
123
124/* clicks to bytes */
125#define	ctob(x)	((x)<<PGSHIFT)
126
127/* bytes to clicks */
128#define	btoc(x)	(((unsigned)(x)+(NBPG-1))>>PGSHIFT)
129
130#define	btodb(bytes)	 		/* calculates (bytes / DEV_BSIZE) */ \
131	((unsigned)(bytes) >> DEV_BSHIFT)
132#define	dbtob(db)			/* calculates (db * DEV_BSIZE) */ \
133	((unsigned)(db) << DEV_BSHIFT)
134
135/*
136 * Map a ``block device block'' to a file system block.
137 * This should be device dependent, and will be if we
138 * add an entry to cdevsw/bdevsw for that purpose.
139 * For now though just use DEV_BSIZE.
140 */
141#define	bdbtofsb(bn)	((bn) / (BLKDEV_IOSIZE/DEV_BSIZE))
142
143/*
144 * Mach derived conversion macros
145 */
146#define i386_round_pdr(x)	((((unsigned)(x)) + NBPDR - 1) & ~(NBPDR-1))
147#define i386_trunc_pdr(x)	((unsigned)(x) & ~(NBPDR-1))
148#define i386_round_page(x)	((((unsigned)(x)) + NBPG - 1) & ~(NBPG-1))
149#define i386_trunc_page(x)	((unsigned)(x) & ~(NBPG-1))
150#define i386_btod(x)		((unsigned)(x) >> PDRSHIFT)
151#define i386_dtob(x)		((unsigned)(x) << PDRSHIFT)
152#define i386_btop(x)		((unsigned)(x) >> PGSHIFT)
153#define i386_ptob(x)		((unsigned)(x) << PGSHIFT)
154