xref: /freebsd/sys/i386/include/vmparam.h (revision af23369a6deaaeb612ab266eb88b8bb8d560c322)
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 #ifndef _MACHINE_VMPARAM_H_
41 #define _MACHINE_VMPARAM_H_ 1
42 
43 /*
44  * Machine dependent constants for 386.
45  */
46 
47 /*
48  * Virtual memory related constants, all in bytes
49  */
50 #define	MAXTSIZ		(128UL*1024*1024)	/* max text size */
51 #ifndef DFLDSIZ
52 #define	DFLDSIZ		(128UL*1024*1024)	/* initial data size limit */
53 #endif
54 #ifndef MAXDSIZ
55 #define	MAXDSIZ		(512UL*1024*1024)	/* max data size */
56 #endif
57 #ifndef	DFLSSIZ
58 #define	DFLSSIZ		(8UL*1024*1024)		/* initial stack size limit */
59 #endif
60 #ifndef	MAXSSIZ
61 #define	MAXSSIZ		(64UL*1024*1024)	/* max stack size */
62 #endif
63 #ifndef SGROWSIZ
64 #define SGROWSIZ	(128UL*1024)		/* amount to grow stack */
65 #endif
66 
67 /*
68  * Choose between DENSE and SPARSE based on whether lower execution time or
69  * lower kernel address space consumption is desired.  Under PAE, kernel
70  * address space is often in short supply.
71  */
72 #ifdef PAE
73 #define	VM_PHYSSEG_SPARSE
74 #else
75 #define	VM_PHYSSEG_DENSE
76 #endif
77 
78 /*
79  * The number of PHYSSEG entries must be one greater than the number
80  * of phys_avail entries because the phys_avail entry that spans the
81  * largest physical address that is accessible by ISA DMA is split
82  * into two PHYSSEG entries.
83  */
84 #define	VM_PHYSSEG_MAX		17
85 
86 /*
87  * Create one free page pool.  Since the i386 kernel virtual address
88  * space does not include a mapping onto the machine's entire physical
89  * memory, VM_FREEPOOL_DIRECT is defined as an alias for the default
90  * pool, VM_FREEPOOL_DEFAULT.
91  */
92 #define	VM_NFREEPOOL		1
93 #define	VM_FREEPOOL_DEFAULT	0
94 #define	VM_FREEPOOL_DIRECT	0
95 
96 /*
97  * Create up to three free page lists: VM_FREELIST_DMA32 is for physical pages
98  * that have physical addresses below 4G but are not accessible by ISA DMA,
99  * and VM_FREELIST_ISADMA is for physical pages that are accessible by ISA
100  * DMA.
101  */
102 #define	VM_NFREELIST		3
103 #define	VM_FREELIST_DEFAULT	0
104 #define	VM_FREELIST_DMA32	1
105 #define	VM_FREELIST_LOWMEM	2
106 
107 #define VM_LOWMEM_BOUNDARY	(16 << 20)	/* 16MB ISA DMA limit */
108 
109 /*
110  * Always create DMA32 freelist if there is any memory above 4G.
111  * Bounce dma is extremely fragile and simultaneously intensively
112  * used.
113  */
114 #define	VM_DMA32_NPAGES_THRESHOLD	1
115 
116 /*
117  * The largest allocation size is 2MB under PAE and 4MB otherwise.
118  */
119 #define	VM_NFREEORDER_PAE		10
120 #define	VM_NFREEORDER_NOPAE		11
121 #define	VM_NFREEORDER_MAX		VM_NFREEORDER_NOPAE
122 #define	VM_NFREEORDER			i386_pmap_VM_NFREEORDER
123 
124 /*
125  * Enable superpage reservations: 1 level.
126  */
127 #ifndef	VM_NRESERVLEVEL
128 #define	VM_NRESERVLEVEL		1
129 #endif
130 
131 /*
132  * Level 0 reservations consist of 512 pages when PAE pagetables are
133  * used, and 1024 pages otherwise.
134  */
135 #ifndef	VM_LEVEL_0_ORDER
136 #define	VM_LEVEL_0_ORDER_PAE	9
137 #define	VM_LEVEL_0_ORDER_NOPAE	10
138 #define	VM_LEVEL_0_ORDER_MAX	VM_LEVEL_0_ORDER_NOPAE
139 #define	VM_LEVEL_0_ORDER	i386_pmap_VM_LEVEL_0_ORDER
140 #else
141 #define	VM_LEVEL_0_ORDER_MAX	VM_LEVEL_0_ORDER
142 #endif
143 
144 /*
145  * Kernel physical load address.
146  */
147 #ifndef KERNLOAD
148 #define	KERNLOAD		(8 * 1024 * 1024)
149 #endif /* !defined(KERNLOAD) */
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	(0xffffffffU - 16 * 1024 * 1024 + 1)
159 
160 #define VM_MIN_KERNEL_ADDRESS	0
161 
162 #define	KERNBASE		KERNLOAD
163 
164 #define UPT_MAX_ADDRESS		VADDR(PTDPTDI, PTDPTDI)
165 #define UPT_MIN_ADDRESS		VADDR(PTDPTDI, 0)
166 
167 #define VM_MAXUSER_ADDRESS	(0xffffffff - 4 * 1024 * 1024 + 1)
168 
169 #define	SHAREDPAGE		(VM_MAXUSER_ADDRESS - PAGE_SIZE)
170 #define	USRSTACK		SHAREDPAGE
171 
172 #define VM_MAX_ADDRESS		VADDR(PTDPTDI, 0)
173 #define VM_MIN_ADDRESS		((vm_offset_t)0)
174 
175 #define	PMAP_TRM_MIN_ADDRESS	VM_MAXUSER_ADDRESS
176 #define	PMAP_TRM_MAX_ADDRESS	0xffffffff
177 
178 #define	PMAP_MAP_LOW		(4 * 1024 * 1024)
179 
180 /*
181  * KVA layout.  The unit of the system allocation is single PDE, which
182  * represents NBPDR bytes, aligned to NBPDR.  NBPDR is 4M for non-PAE
183  * page tables, and 2M for PAE, so PAE mode requires twice as many PTDs
184  * to create the same memory map as non-PAE.
185  *
186  * 0x00000000 - 0x003fffff	Transient identity map of low memory (0-4M),
187  *				normally disabled to catch NULL derefs.
188  * 0x00400000 - 0x007fffff	Fixed mapping of the low memory (4-8M).
189  * 0x00800000 - 0xffbfffff	KERNBASE (VA) == KERNLOAD (PA), kernel
190  *				text + data and all kernel maps.  Managed
191  *				by MI VM.
192  * 0xffc00000 - 0xffdfffff	Recursive kernel page table mapping, pointed
193  *				to by PTmap.  PTD[] recursively points
194  *				into PTmap.
195  * 0xffe00000 - 0xffffffff	Kernel/User mode shared PDE, contains GDT,
196  *				IDT, TSS, LDT, trampoline code and stacks.
197  *				Managed by pmap_trm_alloc().
198  */
199 
200 /*
201  * How many physical pages per kmem arena virtual page.
202  */
203 #ifndef VM_KMEM_SIZE_SCALE
204 #define	VM_KMEM_SIZE_SCALE	(1)
205 #endif
206 
207 /*
208  * Optional floor (in bytes) on the size of the kmem arena.
209  */
210 #ifndef VM_KMEM_SIZE_MIN
211 #define	VM_KMEM_SIZE_MIN	(12 * 1024 * 1024)
212 #endif
213 
214 /*
215  * Optional ceiling (in bytes) on the size of the kmem arena: 40% of the
216  * kernel map rounded to the nearest multiple of the superpage size.
217  */
218 #ifndef VM_KMEM_SIZE_MAX
219 #define	VM_KMEM_SIZE_MAX	(((((VM_MAX_KERNEL_ADDRESS - \
220     VM_MIN_KERNEL_ADDRESS) >> (PDRSHIFT - 2)) + 5) / 10) << PDRSHIFT)
221 #endif
222 
223 /* initial pagein size of beginning of executable file */
224 #ifndef VM_INITIAL_PAGEIN
225 #define	VM_INITIAL_PAGEIN	16
226 #endif
227 
228 #define	ZERO_REGION_SIZE	(64 * 1024)	/* 64KB */
229 
230 #ifndef VM_MAX_AUTOTUNE_MAXUSERS
231 #define VM_MAX_AUTOTUNE_MAXUSERS 384
232 #endif
233 
234 #define	SFBUF
235 #define	SFBUF_MAP
236 #define	SFBUF_CPUSET
237 #define	SFBUF_PROCESS_PAGE
238 
239 #define	PMAP_HAS_DMAP	0
240 #define	PHYS_TO_DMAP(x)	({ panic("No direct map exists"); 0; })
241 #define	DMAP_TO_PHYS(x)	({ panic("No direct map exists"); 0; })
242 
243 /*
244  * No non-transparent large page support in the pmap.
245  */
246 #define	PMAP_HAS_LARGEPAGES	0
247 
248 /*
249  * Need a page dump array for minidump.
250  */
251 #define MINIDUMP_PAGE_TRACKING	1
252 
253 #endif /* _MACHINE_VMPARAM_H_ */
254