xref: /minix/sys/arch/i386/include/vmparam.h (revision 0a6a1f1d)
1 /*	$NetBSD: vmparam.h,v 1.81 2014/07/24 13:42:28 riastradh Exp $	*/
2 
3 /*-
4  * Copyright (c) 1990 The Regents of the University of California.
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  * 3. 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  *	@(#)vmparam.h	5.9 (Berkeley) 5/12/91
35  */
36 
37 #ifndef _I386_VMPARAM_H_
38 #define _I386_VMPARAM_H_
39 
40 #include <sys/tree.h>
41 #include <sys/mutex.h>
42 
43 /*
44  * Machine dependent constants for 386.
45  */
46 
47 /*
48  * Page size on the IA-32 is not variable in the traditional sense.
49  * We override the PAGE_* definitions to compile-time constants.
50  */
51 #define	PAGE_SHIFT	12
52 #define	PAGE_SIZE	(1 << PAGE_SHIFT)
53 #define	PAGE_MASK	(PAGE_SIZE - 1)
54 
55 /*
56  * Virtual address space arrangement. On 386, both user and kernel
57  * share the address space, not unlike the vax.
58  * USRSTACK is the top (end) of the user stack. Immediately above the
59  * user stack is the page table map, and then kernel address space.
60  */
61 #define	USRSTACK	VM_MAXUSER_ADDRESS
62 
63 /*
64  * Virtual memory related constants, all in bytes
65  */
66 #define	MAXTSIZ		(256*1024*1024)		/* max text size */
67 #ifndef DFLDSIZ
68 #define	DFLDSIZ		(256*1024*1024)		/* initial data size limit */
69 #endif
70 #ifndef MAXDSIZ
71 #define	MAXDSIZ		(3U*1024*1024*1024)	/* 3G max data size */
72 #endif
73 #ifndef MAXDSIZ_BU
74 #define	MAXDSIZ_BU	(2U*1024*1024*1024 +	/* 2.5G max data size for */ \
75 			 1U* 512*1024*1024)	/* bottom-up allocation */ \
76 						/* could be a bit more */
77 #endif
78 #ifndef	DFLSSIZ
79 #define	DFLSSIZ		(2*1024*1024)		/* initial stack size limit */
80 #endif
81 #ifndef	MAXSSIZ
82 #define	MAXSSIZ		(64*1024*1024)		/* max stack size */
83 #endif
84 
85 /*
86  * IA-32 can't do per-page execute permission, so instead we implement
87  * two executable segments for %cs, one that covers everything and one
88  * that excludes some of the address space (currently just the stack).
89  * I386_MAX_EXE_ADDR is the upper boundary for the smaller segment.
90  */
91 #define I386_MAX_EXE_ADDR	(USRSTACK - MAXSSIZ)
92 
93 /*
94  * Size of User Raw I/O map
95  */
96 #define	USRIOSIZE 	300
97 
98 /*
99  * Mach derived constants
100  */
101 
102 /* user/kernel map constants */
103 #define VM_MIN_ADDRESS		((vaddr_t)0)
104 #define	VM_MAXUSER_ADDRESS	((vaddr_t)(PDIR_SLOT_PTE << L2_SHIFT))
105 #define	VM_MAX_ADDRESS		\
106 	((vaddr_t)((PDIR_SLOT_PTE << L2_SHIFT) + (PDIR_SLOT_PTE << L1_SHIFT)))
107 #define	VM_MIN_KERNEL_ADDRESS	((vaddr_t)(PDIR_SLOT_KERN << L2_SHIFT))
108 #define	VM_MAX_KERNEL_ADDRESS	((vaddr_t)((PDIR_SLOT_KERN + NKL2_MAX_ENTRIES) << L2_SHIFT))
109 
110 /*
111  * The address to which unspecified mapping requests default
112  */
113 #ifdef _KERNEL_OPT
114 #include "opt_uvm.h"
115 #include "opt_xen.h"
116 #endif
117 #define __USE_TOPDOWN_VM
118 #define VM_DEFAULT_ADDRESS_TOPDOWN(da, sz) \
119     trunc_page(USRSTACK - MAXSSIZ - (sz))
120 #define VM_DEFAULT_ADDRESS_BOTTOMUP(da, sz) \
121     round_page((vaddr_t)(da) + (vsize_t)MIN(maxdmap, MAXDSIZ_BU))
122 
123 /* XXX max. amount of KVM to be used by buffers. */
124 #ifndef VM_MAX_KERNEL_BUF
125 #define VM_MAX_KERNEL_BUF	(384 * 1024 * 1024)
126 #endif
127 
128 /* virtual sizes (bytes) for various kernel submaps */
129 #define VM_PHYS_SIZE		(USRIOSIZE*PAGE_SIZE)
130 
131 #define VM_PHYSSEG_STRAT	VM_PSTRAT_BIGFIRST
132 
133 #ifdef XEN
134 #define	VM_PHYSSEG_MAX		1
135 #define	VM_NFREELIST		1
136 #else
137 #define	VM_PHYSSEG_MAX		32	/* 1 "hole" + 31 free lists */
138 #define	VM_NFREELIST		4
139 #define	VM_FREELIST_FIRST16	3
140 #define	VM_FREELIST_FIRST1G	2
141 #define	VM_FREELIST_FIRST4G	1
142 #endif /* XEN */
143 #define	VM_FREELIST_DEFAULT	0
144 
145 #endif /* _I386_VMPARAM_H_ */
146