xref: /freebsd/sys/i386/include/vmparam.h (revision 734e82fe33aa764367791a7d603b383996c6b40b)
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  */
38 
39 #ifndef _MACHINE_VMPARAM_H_
40 #define _MACHINE_VMPARAM_H_ 1
41 
42 /*
43  * Machine dependent constants for 386.
44  */
45 
46 /*
47  * Virtual memory related constants, all in bytes
48  */
49 #define	MAXTSIZ		(128UL*1024*1024)	/* max text size */
50 #ifndef DFLDSIZ
51 #define	DFLDSIZ		(128UL*1024*1024)	/* initial data size limit */
52 #endif
53 #ifndef MAXDSIZ
54 #define	MAXDSIZ		(512UL*1024*1024)	/* max data size */
55 #endif
56 #ifndef	DFLSSIZ
57 #define	DFLSSIZ		(8UL*1024*1024)		/* initial stack size limit */
58 #endif
59 #ifndef	MAXSSIZ
60 #define	MAXSSIZ		(64UL*1024*1024)	/* max stack size */
61 #endif
62 #ifndef SGROWSIZ
63 #define SGROWSIZ	(128UL*1024)		/* amount to grow stack */
64 #endif
65 
66 /*
67  * Choose between DENSE and SPARSE based on whether lower execution time or
68  * lower kernel address space consumption is desired.  Under PAE, kernel
69  * address space is often in short supply.
70  */
71 #ifdef PAE
72 #define	VM_PHYSSEG_SPARSE
73 #else
74 #define	VM_PHYSSEG_DENSE
75 #endif
76 
77 /*
78  * The number of PHYSSEG entries must be one greater than the number
79  * of phys_avail entries because the phys_avail entry that spans the
80  * largest physical address that is accessible by ISA DMA is split
81  * into two PHYSSEG entries.
82  */
83 #define	VM_PHYSSEG_MAX		17
84 
85 /*
86  * Create one free page pool.  Since the i386 kernel virtual address
87  * space does not include a mapping onto the machine's entire physical
88  * memory, VM_FREEPOOL_DIRECT is defined as an alias for the default
89  * pool, VM_FREEPOOL_DEFAULT.
90  */
91 #define	VM_NFREEPOOL		1
92 #define	VM_FREEPOOL_DEFAULT	0
93 #define	VM_FREEPOOL_DIRECT	0
94 
95 /*
96  * Create up to three free page lists: VM_FREELIST_DMA32 is for physical pages
97  * that have physical addresses below 4G but are not accessible by ISA DMA,
98  * and VM_FREELIST_ISADMA is for physical pages that are accessible by ISA
99  * DMA.
100  */
101 #define	VM_NFREELIST		3
102 #define	VM_FREELIST_DEFAULT	0
103 #define	VM_FREELIST_DMA32	1
104 #define	VM_FREELIST_LOWMEM	2
105 
106 #define VM_LOWMEM_BOUNDARY	(16 << 20)	/* 16MB ISA DMA limit */
107 
108 /*
109  * Always create DMA32 freelist if there is any memory above 4G.
110  * Bounce dma is extremely fragile and simultaneously intensively
111  * used.
112  */
113 #define	VM_DMA32_NPAGES_THRESHOLD	1
114 
115 /*
116  * The largest allocation size is 2MB under PAE and 4MB otherwise.
117  */
118 #define	VM_NFREEORDER_PAE		10
119 #define	VM_NFREEORDER_NOPAE		11
120 #define	VM_NFREEORDER_MAX		VM_NFREEORDER_NOPAE
121 #define	VM_NFREEORDER			i386_pmap_VM_NFREEORDER
122 
123 /*
124  * Enable superpage reservations: 1 level.
125  */
126 #ifndef	VM_NRESERVLEVEL
127 #define	VM_NRESERVLEVEL		1
128 #endif
129 
130 /*
131  * Level 0 reservations consist of 512 pages when PAE pagetables are
132  * used, and 1024 pages otherwise.
133  */
134 #ifndef	VM_LEVEL_0_ORDER
135 #define	VM_LEVEL_0_ORDER_PAE	9
136 #define	VM_LEVEL_0_ORDER_NOPAE	10
137 #define	VM_LEVEL_0_ORDER_MAX	VM_LEVEL_0_ORDER_NOPAE
138 #define	VM_LEVEL_0_ORDER	i386_pmap_VM_LEVEL_0_ORDER
139 #else
140 #define	VM_LEVEL_0_ORDER_MAX	VM_LEVEL_0_ORDER
141 #endif
142 
143 /*
144  * Kernel physical load address.
145  */
146 #ifndef KERNLOAD
147 #define	KERNLOAD		(8 * 1024 * 1024)
148 #endif /* !defined(KERNLOAD) */
149 
150 /*
151  * Virtual addresses of things.  Derived from the page directory and
152  * page table indexes from pmap.h for precision.
153  * Because of the page that is both a PD and PT, it looks a little
154  * messy at times, but hey, we'll do anything to save a page :-)
155  */
156 
157 #define VM_MAX_KERNEL_ADDRESS	(0xffffffffU - 16 * 1024 * 1024 + 1)
158 
159 #define VM_MIN_KERNEL_ADDRESS	0
160 
161 #define	KERNBASE		KERNLOAD
162 
163 #define UPT_MAX_ADDRESS		VADDR(PTDPTDI, PTDPTDI)
164 #define UPT_MIN_ADDRESS		VADDR(PTDPTDI, 0)
165 
166 #define VM_MAXUSER_ADDRESS	(0xffffffff - 4 * 1024 * 1024 + 1)
167 
168 #define	SHAREDPAGE		(VM_MAXUSER_ADDRESS - PAGE_SIZE)
169 #define	USRSTACK		SHAREDPAGE
170 
171 #define VM_MAX_ADDRESS		VADDR(PTDPTDI, 0)
172 #define VM_MIN_ADDRESS		((vm_offset_t)0)
173 
174 #define	PMAP_TRM_MIN_ADDRESS	VM_MAXUSER_ADDRESS
175 #define	PMAP_TRM_MAX_ADDRESS	0xffffffff
176 
177 #define	PMAP_MAP_LOW		(4 * 1024 * 1024)
178 
179 /*
180  * KVA layout.  The unit of the system allocation is single PDE, which
181  * represents NBPDR bytes, aligned to NBPDR.  NBPDR is 4M for non-PAE
182  * page tables, and 2M for PAE, so PAE mode requires twice as many PTDs
183  * to create the same memory map as non-PAE.
184  *
185  * 0x00000000 - 0x003fffff	Transient identity map of low memory (0-4M),
186  *				normally disabled to catch NULL derefs.
187  * 0x00400000 - 0x007fffff	Fixed mapping of the low memory (4-8M).
188  * 0x00800000 - 0xffbfffff	KERNBASE (VA) == KERNLOAD (PA), kernel
189  *				text + data and all kernel maps.  Managed
190  *				by MI VM.
191  * 0xffc00000 - 0xffdfffff	Recursive kernel page table mapping, pointed
192  *				to by PTmap.  PTD[] recursively points
193  *				into PTmap.
194  * 0xffe00000 - 0xffffffff	Kernel/User mode shared PDE, contains GDT,
195  *				IDT, TSS, LDT, trampoline code and stacks.
196  *				Managed by pmap_trm_alloc().
197  */
198 
199 /*
200  * How many physical pages per kmem arena virtual page.
201  */
202 #ifndef VM_KMEM_SIZE_SCALE
203 #define	VM_KMEM_SIZE_SCALE	(1)
204 #endif
205 
206 /*
207  * Optional floor (in bytes) on the size of the kmem arena.
208  */
209 #ifndef VM_KMEM_SIZE_MIN
210 #define	VM_KMEM_SIZE_MIN	(12 * 1024 * 1024)
211 #endif
212 
213 /*
214  * Optional ceiling (in bytes) on the size of the kmem arena: 40% of the
215  * kernel map rounded to the nearest multiple of the superpage size.
216  */
217 #ifndef VM_KMEM_SIZE_MAX
218 #define	VM_KMEM_SIZE_MAX	(((((VM_MAX_KERNEL_ADDRESS - \
219     VM_MIN_KERNEL_ADDRESS) >> (PDRSHIFT - 2)) + 5) / 10) << PDRSHIFT)
220 #endif
221 
222 /* initial pagein size of beginning of executable file */
223 #ifndef VM_INITIAL_PAGEIN
224 #define	VM_INITIAL_PAGEIN	16
225 #endif
226 
227 #define	ZERO_REGION_SIZE	(64 * 1024)	/* 64KB */
228 
229 #ifndef VM_MAX_AUTOTUNE_MAXUSERS
230 #define VM_MAX_AUTOTUNE_MAXUSERS 384
231 #endif
232 
233 #define	SFBUF
234 #define	SFBUF_MAP
235 #define	SFBUF_CPUSET
236 #define	SFBUF_PROCESS_PAGE
237 
238 #define	PMAP_HAS_DMAP	0
239 #define	PHYS_TO_DMAP(x)	({ panic("No direct map exists"); 0; })
240 #define	DMAP_TO_PHYS(x)	({ panic("No direct map exists"); 0; })
241 
242 /*
243  * No non-transparent large page support in the pmap.
244  */
245 #define	PMAP_HAS_LARGEPAGES	0
246 
247 /*
248  * Need a page dump array for minidump.
249  */
250 #define MINIDUMP_PAGE_TRACKING	1
251 
252 #endif /* _MACHINE_VMPARAM_H_ */
253