xref: /freebsd/sys/i386/include/vmparam.h (revision 9336e0699bda8a301cd2bfa37106b6ec5e32012e)
1 /*-
2  * Copyright (c) 1990 The Regents of the University of California.
3  * All rights reserved.
4  * Copyright (c) 1994 John S. Dyson
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * William Jolitz.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 4. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	from: @(#)vmparam.h	5.9 (Berkeley) 5/12/91
35  * $FreeBSD$
36  */
37 
38 
39 #ifndef _MACHINE_VMPARAM_H_
40 #define _MACHINE_VMPARAM_H_ 1
41 
42 /*
43  * Machine dependent constants for 386.
44  */
45 
46 #ifndef PAE
47 #define VM_PROT_READ_IS_EXEC	/* if you can read -- then you can exec */
48 #endif
49 
50 /*
51  * Virtual memory related constants, all in bytes
52  */
53 #define	MAXTSIZ		(128UL*1024*1024)	/* max text size */
54 #ifndef DFLDSIZ
55 #define	DFLDSIZ		(128UL*1024*1024)	/* initial data size limit */
56 #endif
57 #ifndef MAXDSIZ
58 #define	MAXDSIZ		(512UL*1024*1024)	/* max data size */
59 #endif
60 #ifndef	DFLSSIZ
61 #define	DFLSSIZ		(8UL*1024*1024)		/* initial stack size limit */
62 #endif
63 #ifndef	MAXSSIZ
64 #define	MAXSSIZ		(64UL*1024*1024)	/* max stack size */
65 #endif
66 #ifndef SGROWSIZ
67 #define SGROWSIZ	(128UL*1024)		/* amount to grow stack */
68 #endif
69 
70 /*
71  * The time for a process to be blocked before being very swappable.
72  * This is a number of seconds which the system takes as being a non-trivial
73  * amount of real time.  You probably shouldn't change this;
74  * it is used in subtle ways (fractions and multiples of it are, that is, like
75  * half of a ``long time'', almost a long time, etc.)
76  * It is related to human patience and other factors which don't really
77  * change over time.
78  */
79 #define	MAXSLP 		20
80 
81 
82 /*
83  * The physical address space is densely populated.
84  */
85 #define	VM_PHYSSEG_DENSE
86 
87 /*
88  * The number of PHYSSEG entries must be one greater than the number
89  * of phys_avail entries because the phys_avail entry that spans the
90  * largest physical address that is accessible by ISA DMA is split
91  * into two PHYSSEG entries.
92  */
93 #define	VM_PHYSSEG_MAX		17
94 
95 /*
96  * Create two free page pools.  Since the i386 kernel virtual address
97  * space does not include a mapping onto the machine's entire physical
98  * memory, VM_FREEPOOL_DIRECT is defined as an alias for the default
99  * pool, VM_FREEPOOL_DEFAULT.
100  */
101 #define	VM_NFREEPOOL		2
102 #define	VM_FREEPOOL_CACHE	1
103 #define	VM_FREEPOOL_DEFAULT	0
104 #define	VM_FREEPOOL_DIRECT	0
105 
106 /*
107  * Create two free page lists: VM_FREELIST_DEFAULT is for physical
108  * pages that are above the largest physical address that is
109  * accessible by ISA DMA and VM_FREELIST_ISADMA is for physical pages
110  * that are below that address.
111  */
112 #define	VM_NFREELIST		2
113 #define	VM_FREELIST_DEFAULT	0
114 #define	VM_FREELIST_ISADMA	1
115 
116 /*
117  * The largest allocation size is 2MB under PAE and 4MB otherwise.
118  */
119 #ifdef PAE
120 #define	VM_NFREEORDER		10
121 #else
122 #define	VM_NFREEORDER		11
123 #endif
124 
125 /*
126  * Disable superpage reservations.
127  */
128 #ifndef	VM_NRESERVLEVEL
129 #define	VM_NRESERVLEVEL		0
130 #endif
131 
132 /*
133  * Level 0 reservations consist of 512 pages under PAE and 1024 pages
134  * otherwise.
135  */
136 #ifndef	VM_LEVEL_0_ORDER
137 #ifdef PAE
138 #define	VM_LEVEL_0_ORDER	9
139 #else
140 #define	VM_LEVEL_0_ORDER	10
141 #endif
142 #endif
143 
144 /*
145  * Kernel physical load address.
146  */
147 #ifndef KERNLOAD
148 #define	KERNLOAD		(1 << PDRSHIFT)
149 #endif
150 
151 /*
152  * Virtual addresses of things.  Derived from the page directory and
153  * page table indexes from pmap.h for precision.
154  * Because of the page that is both a PD and PT, it looks a little
155  * messy at times, but hey, we'll do anything to save a page :-)
156  */
157 
158 #define VM_MAX_KERNEL_ADDRESS	VADDR(KPTDI+NKPDE-1, NPTEPG-1)
159 #define VM_MIN_KERNEL_ADDRESS	VADDR(PTDPTDI, PTDPTDI)
160 
161 #define	KERNBASE		VADDR(KPTDI, 0)
162 
163 #define UPT_MAX_ADDRESS		VADDR(PTDPTDI, PTDPTDI)
164 #define UPT_MIN_ADDRESS		VADDR(PTDPTDI, 0)
165 
166 #define VM_MAXUSER_ADDRESS	VADDR(PTDPTDI, 0)
167 
168 #define USRSTACK		VM_MAXUSER_ADDRESS
169 
170 #define VM_MAX_ADDRESS		VADDR(PTDPTDI, PTDPTDI)
171 #define VM_MIN_ADDRESS		((vm_offset_t)0)
172 
173 /* virtual sizes (bytes) for various kernel submaps */
174 #ifndef VM_KMEM_SIZE
175 #define VM_KMEM_SIZE		(12 * 1024 * 1024)
176 #endif
177 
178 /*
179  * How many physical pages per KVA page allocated.
180  * min(max(max(VM_KMEM_SIZE, Physical memory/VM_KMEM_SIZE_SCALE),
181  *     VM_KMEM_SIZE_MIN), VM_KMEM_SIZE_MAX)
182  * is the total KVA space allocated for kmem_map.
183  */
184 #ifndef VM_KMEM_SIZE_SCALE
185 #define	VM_KMEM_SIZE_SCALE	(3)
186 #endif
187 
188 /*
189  * Ceiling on amount of kmem_map kva space.
190  */
191 #ifndef VM_KMEM_SIZE_MAX
192 #define	VM_KMEM_SIZE_MAX	(320 * 1024 * 1024)
193 #endif
194 
195 /* initial pagein size of beginning of executable file */
196 #ifndef VM_INITIAL_PAGEIN
197 #define	VM_INITIAL_PAGEIN	16
198 #endif
199 
200 #endif /* _MACHINE_VMPARAM_H_ */
201