xref: /openbsd-src/sys/arch/i386/include/param.h (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1 /*	$OpenBSD: param.h,v 1.18 2001/07/18 10:47:04 art Exp $	*/
2 /*	$NetBSD: param.h,v 1.29 1996/03/04 05:04:26 cgd Exp $	*/
3 
4 /*-
5  * Copyright (c) 1990 The Regents of the University of California.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * William Jolitz.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the University of
22  *	California, Berkeley and its contributors.
23  * 4. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  *
39  *	@(#)param.h	5.8 (Berkeley) 6/28/91
40  */
41 
42 /*
43  * Machine dependent constants for Intel 386.
44  */
45 
46 #ifdef _KERNEL
47 #ifdef _LOCORE
48 #include <machine/psl.h>
49 #else
50 #include <machine/cpu.h>
51 #endif
52 #endif
53 
54 #define	_MACHINE	i386
55 #define	MACHINE		"i386"
56 #define	_MACHINE_ARCH	i386
57 #define	MACHINE_ARCH	"i386"
58 #define	MID_MACHINE	MID_I386
59 
60 /*
61  * Round p (pointer or byte index) up to a correctly-aligned value
62  * for all data types (int, long, ...).   The result is u_int and
63  * must be cast to any desired pointer type.
64  */
65 #define ALIGNBYTES	(sizeof(int) - 1)
66 #define ALIGN(p)	(((u_int)(p) + ALIGNBYTES) &~ ALIGNBYTES)
67 
68 #define	PGSHIFT		12		/* LOG2(NBPG) */
69 #define	NBPG		(1 << PGSHIFT)	/* bytes/page */
70 #define	PGOFSET		(NBPG-1)	/* byte offset into page */
71 
72 #define PAGE_SHIFT	12
73 #define PAGE_SIZE	(1 << PAGE_SHIFT)
74 #define PAGE_MASK	(PAGE_SIZE - 1)
75 
76 #define	NPTEPG		(NBPG/(sizeof (pt_entry_t)))
77 
78 #define	KERNBASE	0xe0000000		/* start of kernel virtual space */
79 #define	KERNTEXTOFF	(KERNBASE+0x100000)	/* start of kernel text */
80 #define	BTOPKERNBASE	((u_long)KERNBASE >> PGSHIFT)
81 
82 #define	DEV_BSHIFT	9		/* log2(DEV_BSIZE) */
83 #define	DEV_BSIZE	(1 << DEV_BSHIFT)
84 #define	BLKDEV_IOSIZE	2048
85 #ifndef	MAXPHYS
86 #define	MAXPHYS		(64 * 1024)	/* max raw I/O transfer size */
87 #endif
88 
89 #define	SSIZE		1		/* initial stack size/NBPG */
90 #define	SINCR		1		/* increment of stack/NBPG */
91 #define	UPAGES		2		/* pages of u-area */
92 #define	USPACE		(UPAGES * NBPG)	/* total size of u-area */
93 
94 #ifndef MSGBUFSIZE
95 #define MSGBUFSIZE	2*NBPG		/* default message buffer size */
96 #endif
97 
98 /*
99  * Constants related to network buffer management.
100  * MCLBYTES must be no larger than the software page size, and,
101  * on machines that exchange pages of input or output buffers with mbuf
102  * clusters (MAPPED_MBUFS), MCLBYTES must also be an integral multiple
103  * of the hardware page size.
104  */
105 #define	MSIZE		256		/* size of an mbuf */
106 #define	MCLSHIFT	11		/* convert bytes to m_buf clusters */
107 #define	MCLBYTES	(1 << MCLSHIFT)	/* size of a m_buf cluster */
108 #define	MCLOFSET	(MCLBYTES - 1)	/* offset within a m_buf cluster */
109 
110 #ifndef NMBCLUSTERS
111 #define	NMBCLUSTERS	2048		/* map size, max cluster allocation */
112 #endif
113 
114 /*
115  * Size of kernel malloc arena in logical pages
116  */
117 #ifndef NKMEMCLUSTERS
118 #define	NKMEMCLUSTERS	(16 * 1024 * 1024 / PAGE_SIZE)
119 #endif
120 
121 /* pages ("clicks") to disk blocks */
122 #define	ctod(x)		((x) << (PGSHIFT - DEV_BSHIFT))
123 #define	dtoc(x)		((x) >> (PGSHIFT - DEV_BSHIFT))
124 
125 /* bytes to pages */
126 #define	ctob(x)		((x) << PGSHIFT)
127 #define	btoc(x)		(((x) + PGOFSET) >> PGSHIFT)
128 
129 /* bytes to disk blocks */
130 #define	dbtob(x)	((x) << DEV_BSHIFT)
131 #define	btodb(x)	((x) >> DEV_BSHIFT)
132 
133 /*
134  * Map a ``block device block'' to a file system block.
135  * This should be device dependent, and should use the bsize
136  * field from the disk label.
137  * For now though just use DEV_BSIZE.
138  */
139 #define	bdbtofsb(bn)	((bn) / (BLKDEV_IOSIZE / DEV_BSIZE))
140 
141 /*
142  * Mach derived conversion macros
143  */
144 #define	i386_round_pdr(x)	((((unsigned)(x)) + PDOFSET) & ~PDOFSET)
145 #define	i386_trunc_pdr(x)	((unsigned)(x) & ~PDOFSET)
146 #define	i386_btod(x)		((unsigned)(x) >> PDSHIFT)
147 #define	i386_dtob(x)		((unsigned)(x) << PDSHIFT)
148 #define	i386_round_page(x)	((((unsigned)(x)) + PGOFSET) & ~PGOFSET)
149 #define	i386_trunc_page(x)	((unsigned)(x) & ~PGOFSET)
150 #define	i386_btop(x)		((unsigned)(x) >> PGSHIFT)
151 #define	i386_ptob(x)		((unsigned)(x) << PGSHIFT)
152