xref: /freebsd/sys/i386/include/param.h (revision 2ad872c5794e4c26fdf6ed219ad3f09ca0d5304a)
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 1.47 1998/10/13 08:24:37 dg Exp $
38  */
39 
40 #ifndef _MACHINE_PARAM_H_
41 #define	_MACHINE_PARAM_H_
42 
43 /*
44  * Machine dependent constants for Intel 386.
45  */
46 #define	_MACHINE	i386
47 #define MACHINE		"i386"
48 #define	_MACHINE_ARCH	i386
49 #define	MACHINE_ARCH	"i386"
50 #define MID_MACHINE	MID_I386
51 
52 /*
53  * OBJFORMAT_NAMES is a comma-separated list of the object formats
54  * that are supported on the architecture.
55  */
56 #define OBJFORMAT_NAMES		"elf", "aout"
57 #define OBJFORMAT_DEFAULT	"elf"
58 
59 #ifdef SMP
60 #define NCPUS		2
61 #else
62 #define NCPUS		1
63 #endif
64 
65 /*
66  * Round p (pointer or byte index) up to a correctly-aligned value
67  * for all data types (int, long, ...).   The result is unsigned int
68  * and must be cast to any desired pointer type.
69  */
70 #define ALIGNBYTES	(sizeof(int) - 1)
71 #define ALIGN(p)	(((unsigned)(p) + ALIGNBYTES) & ~ALIGNBYTES)
72 
73 #define PAGE_SHIFT	12		/* LOG2(PAGE_SIZE) */
74 #define PAGE_SIZE	(1<<PAGE_SHIFT)	/* bytes/page */
75 #define PAGE_MASK	(PAGE_SIZE-1)
76 #define NPTEPG		(PAGE_SIZE/(sizeof (pt_entry_t)))
77 
78 #define NPDEPG		(PAGE_SIZE/(sizeof (pd_entry_t)))
79 #define PDRSHIFT	22		/* LOG2(NBPDR) */
80 #define NBPDR		(1<<PDRSHIFT)	/* bytes/page dir */
81 #define PDRMASK		(NBPDR-1)
82 
83 #define DEV_BSHIFT	9		/* log2(DEV_BSIZE) */
84 #define DEV_BSIZE	(1<<DEV_BSHIFT)
85 
86 #define BLKDEV_IOSIZE	2048
87 #define DFLTPHYS	(64 * 1024)	/* default max raw I/O transfer size */
88 #define MAXPHYS		(128 * 1024)	/* max raw I/O transfer size */
89 
90 #define IOPAGES	2		/* pages of i/o permission bitmap */
91 #define UPAGES	2		/* pages of u-area */
92 #define UPAGES_HOLE	2	/* pages of "hole" at top of user space where */
93 				/* the upages used to be. DO NOT CHANGE! */
94 
95 /*
96  * Constants related to network buffer management.
97  * MCLBYTES must be no larger than CLBYTES (the software page size), and,
98  * on machines that exchange pages of input or output buffers with mbuf
99  * clusters (MAPPED_MBUFS), MCLBYTES must also be an integral multiple
100  * of the hardware page size.
101  */
102 #ifndef	MSIZE
103 #define MSIZE		128		/* size of an mbuf */
104 #endif	/* MSIZE */
105 
106 #ifndef	MCLSHIFT
107 #define MCLSHIFT	11		/* convert bytes to m_buf clusters */
108 #endif	/* MCLSHIFT */
109 #define MCLBYTES	(1 << MCLSHIFT)	/* size of an m_buf cluster */
110 #define MCLOFSET	(MCLBYTES - 1)	/* offset within an m_buf cluster */
111 
112 /*
113  * Some macros for units conversion
114  */
115 
116 /* clicks to bytes */
117 #define ctob(x)	((x)<<PAGE_SHIFT)
118 
119 /* bytes to clicks */
120 #define btoc(x)	(((unsigned)(x)+PAGE_MASK)>>PAGE_SHIFT)
121 
122 /*
123  * btodb() is messy and perhaps slow because `bytes' may be an off_t.  We
124  * want to shift an unsigned type to avoid sign extension and we don't
125  * want to widen `bytes' unnecessarily.  Assume that the result fits in
126  * a daddr_t.
127  */
128 #define btodb(bytes)	 		/* calculates (bytes / DEV_BSIZE) */ \
129 	(sizeof (bytes) > sizeof(long) \
130 	 ? (daddr_t)((unsigned long long)(bytes) >> DEV_BSHIFT) \
131 	 : (daddr_t)((unsigned long)(bytes) >> DEV_BSHIFT))
132 
133 #define dbtob(db)			/* calculates (db * DEV_BSIZE) */ \
134 	((off_t)(db) << DEV_BSHIFT)
135 
136 /*
137  * Mach derived conversion macros
138  */
139 #define trunc_page(x)		((x) & ~PAGE_MASK)
140 #define round_page(x)		(((x) + PAGE_MASK) & ~PAGE_MASK)
141 #define trunc_4mpage(x)		((unsigned)(x) & ~PDRMASK)
142 #define round_4mpage(x)		((((unsigned)(x)) + PDRMASK) & ~PDRMASK)
143 
144 #define atop(x)			((unsigned)(x) >> PAGE_SHIFT)
145 #define ptoa(x)			((unsigned)(x) << PAGE_SHIFT)
146 
147 #define i386_btop(x)		((unsigned)(x) >> PAGE_SHIFT)
148 #define i386_ptob(x)		((unsigned)(x) << PAGE_SHIFT)
149 
150 #endif /* !_MACHINE_PARAM_H_ */
151