xref: /openbsd-src/sys/arch/i386/include/vmparam.h (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1 /*	$OpenBSD: vmparam.h,v 1.20 2001/06/27 06:19:45 art Exp $	*/
2 /*	$NetBSD: vmparam.h,v 1.15 1994/10/27 04:16:34 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  *	@(#)vmparam.h	5.9 (Berkeley) 5/12/91
40  */
41 
42 #ifndef _MACHINE_VM_PARAM_H_
43 #define _MACHINE_VM_PARAM_H_
44 /*
45  * Machine dependent constants for 386.
46  */
47 
48 /*
49  * Virtual address space arrangement. On 386, both user and kernel
50  * share the address space, not unlike the vax.
51  * USRTEXT is the start of the user text/data space, while USRSTACK
52  * is the top (end) of the user stack. Immediately above the user stack
53  * resides the user structure, which is UPAGES long and contains the
54  * kernel stack.
55  *
56  * Immediately after the user structure is the page table map, and then
57  * kernal address space.
58  */
59 #define	USRTEXT		PAGE_SIZE
60 #define	USRSTACK	VM_MAXUSER_ADDRESS
61 
62 /*
63  * Virtual memory related constants, all in bytes
64  */
65 #define	MAXTSIZ		(64*1024*1024)		/* max text size */
66 #ifndef DFLDSIZ
67 #define	DFLDSIZ		(64*1024*1024)		/* initial data size limit */
68 #endif
69 #ifndef MAXDSIZ
70 #define	MAXDSIZ		(1*1024*1024*1024)	/* max data size */
71 #endif
72 #ifndef	DFLSSIZ
73 #define	DFLSSIZ		(4*1024*1024)		/* initial stack size limit */
74 #endif
75 #ifndef	MAXSSIZ
76 #define	MAXSSIZ		(32*1024*1024)		/* max stack size */
77 #endif
78 
79 /*
80  * Default sizes of swap allocation chunks (see dmap.h).
81  * The actual values may be changed in vminit() based on MAXDSIZ.
82  * With MAXDSIZ of 16Mb and NDMAP of 38, dmmax will be 1024.
83  */
84 #define	DMMIN	32			/* smallest swap allocation */
85 #define	DMMAX	4096			/* largest potential swap allocation */
86 #define	DMTEXT	1024			/* swap allocation for text */
87 
88 /*
89  * Size of shared memory map
90  */
91 #ifndef SHMMAXPGS
92 #define SHMMAXPGS	2048
93 #endif
94 
95 /*
96  * Size of User Raw I/O map
97  */
98 #define	USRIOSIZE 	300
99 
100 /*
101  * The time for a process to be blocked before being very swappable.
102  * This is a number of seconds which the system takes as being a non-trivial
103  * amount of real time.  You probably shouldn't change this;
104  * it is used in subtle ways (fractions and multiples of it are, that is, like
105  * half of a ``long time'', almost a long time, etc.)
106  * It is related to human patience and other factors which don't really
107  * change over time.
108  */
109 #define	MAXSLP 		20
110 
111 /*
112  * A swapped in process is given a small amount of core without being bothered
113  * by the page replacement algorithm.  Basically this says that if you are
114  * swapped in you deserve some resources.  We protect the last SAFERSS
115  * pages against paging and will just swap you out rather than paging you.
116  */
117 #define	SAFERSS		8		/* nominal ``small'' resident set size
118 					   protected against replacement */
119 
120 /*
121  * Mach derived constants
122  */
123 
124 /* XXX Compatibility */
125 #define APTDPTDI	PDSLOT_APTE
126 #define PTDPTDI		PDSLOT_PTE
127 
128 /* user/kernel map constants */
129 #define VM_MIN_ADDRESS		((vm_offset_t)0)
130 #define VM_MAXUSER_ADDRESS	((vm_offset_t)((PTDPTDI<<PDSHIFT) - USPACE))
131 #define VM_MAX_ADDRESS		((vm_offset_t)((PTDPTDI<<PDSHIFT) + (PTDPTDI<<PGSHIFT)))
132 #define VM_MIN_KERNEL_ADDRESS	((vm_offset_t)KERNBASE)
133 #define VM_MAX_KERNEL_ADDRESS	((vm_offset_t)(APTDPTDI<<PDSHIFT))
134 
135 /* virtual sizes (bytes) for various kernel submaps */
136 #define VM_MBUF_SIZE		(NMBCLUSTERS*MCLBYTES)
137 #define VM_KMEM_SIZE		(NKMEMCLUSTERS*PAGE_SIZE)
138 #define VM_PHYS_SIZE		(USRIOSIZE*PAGE_SIZE)
139 
140 #define	VM_PHYSSEG_MAX	4	/* actually we could have this many segments */
141 #define	VM_PHYSSEG_STRAT	VM_PSTRAT_BSEARCH
142 #define	VM_PHYSSEG_NOADD	/* can't add RAM after vm_mem_init */
143 
144 #define VM_NFREELIST		2
145 #define VM_FREELIST_DEFAULT	0
146 #define VM_FREELIST_FIRST16	1
147 
148 /*
149  * pmap specific data stored in the vm_physmem[] array
150  */
151 struct pmap_physseg {
152 	struct pv_head *pvhead;		/* pv_head array */
153 	char *attrs;			/* attrs array */
154 };
155 
156 #endif /* _MACHINE_VM_PARAM_H_ */
157