xref: /freebsd/sys/i386/include/vmparam.h (revision 4f52dfbb8d6c4d446500c5b097e3806ec219fbd4)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1990 The Regents of the University of California.
5  * All rights reserved.
6  * Copyright (c) 1994 John S. Dyson
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to Berkeley by
10  * William Jolitz.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. 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: @(#)vmparam.h	5.9 (Berkeley) 5/12/91
37  * $FreeBSD$
38  */
39 
40 
41 #ifndef _MACHINE_VMPARAM_H_
42 #define _MACHINE_VMPARAM_H_ 1
43 
44 /*
45  * Machine dependent constants for 386.
46  */
47 
48 /*
49  * Virtual memory related constants, all in bytes
50  */
51 #define	MAXTSIZ		(128UL*1024*1024)	/* max text size */
52 #ifndef DFLDSIZ
53 #define	DFLDSIZ		(128UL*1024*1024)	/* initial data size limit */
54 #endif
55 #ifndef MAXDSIZ
56 #define	MAXDSIZ		(512UL*1024*1024)	/* max data size */
57 #endif
58 #ifndef	DFLSSIZ
59 #define	DFLSSIZ		(8UL*1024*1024)		/* initial stack size limit */
60 #endif
61 #ifndef	MAXSSIZ
62 #define	MAXSSIZ		(64UL*1024*1024)	/* max stack size */
63 #endif
64 #ifndef SGROWSIZ
65 #define SGROWSIZ	(128UL*1024)		/* amount to grow stack */
66 #endif
67 
68 /*
69  * Choose between DENSE and SPARSE based on whether lower execution time or
70  * lower kernel address space consumption is desired.  Under PAE, kernel
71  * address space is often in short supply.
72  */
73 #ifdef PAE
74 #define	VM_PHYSSEG_SPARSE
75 #else
76 #define	VM_PHYSSEG_DENSE
77 #endif
78 
79 /*
80  * The number of PHYSSEG entries must be one greater than the number
81  * of phys_avail entries because the phys_avail entry that spans the
82  * largest physical address that is accessible by ISA DMA is split
83  * into two PHYSSEG entries.
84  */
85 #define	VM_PHYSSEG_MAX		17
86 
87 /*
88  * Create one free page pool.  Since the i386 kernel virtual address
89  * space does not include a mapping onto the machine's entire physical
90  * memory, VM_FREEPOOL_DIRECT is defined as an alias for the default
91  * pool, VM_FREEPOOL_DEFAULT.
92  */
93 #define	VM_NFREEPOOL		1
94 #define	VM_FREEPOOL_DEFAULT	0
95 #define	VM_FREEPOOL_DIRECT	0
96 
97 /*
98  * Create two free page lists: VM_FREELIST_DEFAULT is for physical
99  * pages that are above the largest physical address that is
100  * accessible by ISA DMA and VM_FREELIST_ISADMA is for physical pages
101  * that are below that address.
102  */
103 #define	VM_NFREELIST		2
104 #define	VM_FREELIST_DEFAULT	0
105 #define	VM_FREELIST_ISADMA	1
106 
107 /*
108  * The largest allocation size is 2MB under PAE and 4MB otherwise.
109  */
110 #ifdef PAE
111 #define	VM_NFREEORDER		10
112 #else
113 #define	VM_NFREEORDER		11
114 #endif
115 
116 /*
117  * Enable superpage reservations: 1 level.
118  */
119 #ifndef	VM_NRESERVLEVEL
120 #define	VM_NRESERVLEVEL		1
121 #endif
122 
123 /*
124  * Level 0 reservations consist of 512 pages when PAE pagetables are
125  * used, and 1024 pages otherwise.
126  */
127 #ifndef	VM_LEVEL_0_ORDER
128 #if defined(PAE) || defined(PAE_TABLES)
129 #define	VM_LEVEL_0_ORDER	9
130 #else
131 #define	VM_LEVEL_0_ORDER	10
132 #endif
133 #endif
134 
135 /*
136  * Kernel physical load address.
137  */
138 #ifndef KERNLOAD
139 #define	KERNLOAD		(KERNPTDI << PDRSHIFT)
140 #endif /* !defined(KERNLOAD) */
141 
142 /*
143  * Virtual addresses of things.  Derived from the page directory and
144  * page table indexes from pmap.h for precision.
145  * Because of the page that is both a PD and PT, it looks a little
146  * messy at times, but hey, we'll do anything to save a page :-)
147  */
148 
149 #define VM_MAX_KERNEL_ADDRESS	VADDR(PTDPTDI, 0)
150 
151 #define VM_MIN_KERNEL_ADDRESS	0
152 
153 #define	KERNBASE		KERNLOAD
154 
155 #define UPT_MAX_ADDRESS		VADDR(PTDPTDI, PTDPTDI)
156 #define UPT_MIN_ADDRESS		VADDR(PTDPTDI, 0)
157 
158 #define VM_MAXUSER_ADDRESS	VADDR(TRPTDI, 0)
159 
160 #define	SHAREDPAGE		(VM_MAXUSER_ADDRESS - PAGE_SIZE)
161 #define	USRSTACK		SHAREDPAGE
162 
163 #define VM_MAX_ADDRESS		VADDR(PTDPTDI, 0)
164 #define VM_MIN_ADDRESS		((vm_offset_t)0)
165 
166 #define	PMAP_TRM_MIN_ADDRESS	VM_MAXUSER_ADDRESS
167 #define	PMAP_TRM_MAX_ADDRESS	0xffffffff
168 
169 #define	PMAP_MAP_LOW		VADDR(LOWPTDI, 0)
170 
171 /*
172  * KVA layout.  The unit of the system allocation is single PDE, which
173  * represents NBPDR bytes, aligned to NBPDR.  NBPDR is 4M for non-PAE
174  * page tables, and 2M for PAE.  Addresses below are shown for non-PAE.
175  *
176  * 0x00000000 - 0x003fffff	Transient identity map of low memory (0-4M),
177  *				normally disabled to catch NULL derefs.
178  * 0x00400000 - 0x007fffff	Fixed mapping of the low memory (0-4M).
179  * 0x00800000 - 0xffbfffff	KERNBASE (VA) == KERNLOAD (PA), kernel
180  *				text + data and all kernel maps.  Managed
181  *				by MI VM.
182  * 0xffc00000 - 0xffdfffff	Recursive kernel page table mapping, pointed
183  *				to by PTmap.  PTD[] recusively points
184  *				into PTmap.
185  * 0xffe00000 - 0xffffffff	Kernel/User mode shared PDE, contains GDT,
186  *				IDT, TSS, LDT, trampoline code and stacks.
187  *				Managed by pmap_trm_alloc().
188  */
189 
190 /*
191  * How many physical pages per kmem arena virtual page.
192  */
193 #ifndef VM_KMEM_SIZE_SCALE
194 #define	VM_KMEM_SIZE_SCALE	(3)
195 #endif
196 
197 /*
198  * Optional floor (in bytes) on the size of the kmem arena.
199  */
200 #ifndef VM_KMEM_SIZE_MIN
201 #define	VM_KMEM_SIZE_MIN	(12 * 1024 * 1024)
202 #endif
203 
204 /*
205  * Optional ceiling (in bytes) on the size of the kmem arena: 40% of the
206  * kernel map rounded to the nearest multiple of the superpage size.
207  */
208 #ifndef VM_KMEM_SIZE_MAX
209 #define	VM_KMEM_SIZE_MAX	(((((VM_MAX_KERNEL_ADDRESS - \
210     VM_MIN_KERNEL_ADDRESS) >> (PDRSHIFT - 2)) + 5) / 10) << PDRSHIFT)
211 #endif
212 
213 /* initial pagein size of beginning of executable file */
214 #ifndef VM_INITIAL_PAGEIN
215 #define	VM_INITIAL_PAGEIN	16
216 #endif
217 
218 #define	ZERO_REGION_SIZE	(64 * 1024)	/* 64KB */
219 
220 #ifndef VM_MAX_AUTOTUNE_MAXUSERS
221 #define VM_MAX_AUTOTUNE_MAXUSERS 384
222 #endif
223 
224 #define	SFBUF
225 #define	SFBUF_MAP
226 #define	SFBUF_CPUSET
227 #define	SFBUF_PROCESS_PAGE
228 
229 #define	PMAP_HAS_DMAP	0
230 #define	PHYS_TO_DMAP(x)	({ panic("No direct map exists"); 0; })
231 #define	DMAP_TO_PHYS(x)	({ panic("No direct map exists"); 0; })
232 
233 #endif /* _MACHINE_VMPARAM_H_ */
234