vmparam.h revision 331722
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 * Copyright (c) 2003 Peter Wemm
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. All advertising materials mentioning features or use of this software
21 *    must display the following acknowledgement:
22 *	This product includes software developed by the University of
23 *	California, Berkeley and its contributors.
24 * 4. Neither the name of the University nor the names of its contributors
25 *    may be used to endorse or promote products derived from this software
26 *    without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * SUCH DAMAGE.
39 *
40 *	from: @(#)vmparam.h	5.9 (Berkeley) 5/12/91
41 * $FreeBSD: stable/11/sys/amd64/include/vmparam.h 331722 2018-03-29 02:50:57Z eadler $
42 */
43
44
45#ifndef _MACHINE_VMPARAM_H_
46#define	_MACHINE_VMPARAM_H_ 1
47
48/*
49 * Machine dependent constants for AMD64.
50 */
51
52/*
53 * Virtual memory related constants, all in bytes
54 */
55#define	MAXTSIZ		(32768UL*1024*1024)	/* max text size */
56#ifndef DFLDSIZ
57#define	DFLDSIZ		(32768UL*1024*1024)	/* initial data size limit */
58#endif
59#ifndef MAXDSIZ
60#define	MAXDSIZ		(32768UL*1024*1024)	/* max data size */
61#endif
62#ifndef	DFLSSIZ
63#define	DFLSSIZ		(8UL*1024*1024)		/* initial stack size limit */
64#endif
65#ifndef	MAXSSIZ
66#define	MAXSSIZ		(512UL*1024*1024)	/* max stack size */
67#endif
68#ifndef SGROWSIZ
69#define	SGROWSIZ	(128UL*1024)		/* amount to grow stack */
70#endif
71
72/*
73 * We provide a machine specific single page allocator through the use
74 * of the direct mapped segment.  This uses 2MB pages for reduced
75 * TLB pressure.
76 */
77#define	UMA_MD_SMALL_ALLOC
78
79/*
80 * The physical address space is densely populated.
81 */
82#define	VM_PHYSSEG_DENSE
83
84/*
85 * The number of PHYSSEG entries must be one greater than the number
86 * of phys_avail entries because the phys_avail entry that spans the
87 * largest physical address that is accessible by ISA DMA is split
88 * into two PHYSSEG entries.
89 */
90#define	VM_PHYSSEG_MAX		63
91
92/*
93 * Create two free page pools: VM_FREEPOOL_DEFAULT is the default pool
94 * from which physical pages are allocated and VM_FREEPOOL_DIRECT is
95 * the pool from which physical pages for page tables and small UMA
96 * objects are allocated.
97 */
98#define	VM_NFREEPOOL		2
99#define	VM_FREEPOOL_DEFAULT	0
100#define	VM_FREEPOOL_DIRECT	1
101
102/*
103 * Create up to three free page lists: VM_FREELIST_DMA32 is for physical pages
104 * that have physical addresses below 4G but are not accessible by ISA DMA,
105 * and VM_FREELIST_ISADMA is for physical pages that are accessible by ISA
106 * DMA.
107 */
108#define	VM_NFREELIST		3
109#define	VM_FREELIST_DEFAULT	0
110#define	VM_FREELIST_DMA32	1
111#define	VM_FREELIST_ISADMA	2
112
113/*
114 * Create the DMA32 free list only if the number of physical pages above
115 * physical address 4G is at least 16M, which amounts to 64GB of physical
116 * memory.
117 */
118#define	VM_DMA32_NPAGES_THRESHOLD	16777216
119
120/*
121 * An allocation size of 16MB is supported in order to optimize the
122 * use of the direct map by UMA.  Specifically, a cache line contains
123 * at most 8 PDEs, collectively mapping 16MB of physical memory.  By
124 * reducing the number of distinct 16MB "pages" that are used by UMA,
125 * the physical memory allocator reduces the likelihood of both 2MB
126 * page TLB misses and cache misses caused by 2MB page TLB misses.
127 */
128#define	VM_NFREEORDER		13
129
130/*
131 * Enable superpage reservations: 1 level.
132 */
133#ifndef	VM_NRESERVLEVEL
134#define	VM_NRESERVLEVEL		1
135#endif
136
137/*
138 * Level 0 reservations consist of 512 pages.
139 */
140#ifndef	VM_LEVEL_0_ORDER
141#define	VM_LEVEL_0_ORDER	9
142#endif
143
144#ifdef	SMP
145#define	PA_LOCK_COUNT	256
146#endif
147
148/*
149 * Virtual addresses of things.  Derived from the page directory and
150 * page table indexes from pmap.h for precision.
151 *
152 * 0x0000000000000000 - 0x00007fffffffffff   user map
153 * 0x0000800000000000 - 0xffff7fffffffffff   does not exist (hole)
154 * 0xffff800000000000 - 0xffff804020100fff   recursive page table (512GB slot)
155 * 0xffff804020101000 - 0xfffff7ffffffffff   unused
156 * 0xfffff80000000000 - 0xfffffbffffffffff   4TB direct map
157 * 0xfffffc0000000000 - 0xfffffdffffffffff   unused
158 * 0xfffffe0000000000 - 0xffffffffffffffff   2TB kernel map
159 *
160 * Within the kernel map:
161 *
162 * 0xffffffff80000000                        KERNBASE
163 */
164
165#define	VM_MIN_KERNEL_ADDRESS	KVADDR(KPML4BASE, 0, 0, 0)
166#define	VM_MAX_KERNEL_ADDRESS	KVADDR(KPML4BASE + NKPML4E - 1, \
167					NPDPEPG-1, NPDEPG-1, NPTEPG-1)
168
169#define	DMAP_MIN_ADDRESS	KVADDR(DMPML4I, 0, 0, 0)
170#define	DMAP_MAX_ADDRESS	KVADDR(DMPML4I + NDMPML4E, 0, 0, 0)
171
172#define	KERNBASE		KVADDR(KPML4I, KPDPI, 0, 0)
173
174#define	UPT_MAX_ADDRESS		KVADDR(PML4PML4I, PML4PML4I, PML4PML4I, PML4PML4I)
175#define	UPT_MIN_ADDRESS		KVADDR(PML4PML4I, 0, 0, 0)
176
177#define	VM_MAXUSER_ADDRESS	UVADDR(NUPML4E, 0, 0, 0)
178
179#define	SHAREDPAGE		(VM_MAXUSER_ADDRESS - PAGE_SIZE)
180#define	USRSTACK		SHAREDPAGE
181
182#define	VM_MAX_ADDRESS		UPT_MAX_ADDRESS
183#define	VM_MIN_ADDRESS		(0)
184
185/*
186 * XXX Allowing dmaplimit == 0 is a temporary workaround for vt(4) efifb's
187 * early use of PHYS_TO_DMAP before the mapping is actually setup. This works
188 * because the result is not actually accessed until later, but the early
189 * vt fb startup needs to be reworked.
190 */
191#define	PHYS_TO_DMAP(x)	({						\
192	KASSERT(dmaplimit == 0 || (x) < dmaplimit,			\
193	    ("physical address %#jx not covered by the DMAP",		\
194	    (uintmax_t)x));						\
195	(x) | DMAP_MIN_ADDRESS; })
196
197#define	DMAP_TO_PHYS(x)	({						\
198	KASSERT((x) < (DMAP_MIN_ADDRESS + dmaplimit) &&			\
199	    (x) >= DMAP_MIN_ADDRESS,					\
200	    ("virtual address %#jx not covered by the DMAP",		\
201	    (uintmax_t)x));						\
202	(x) & ~DMAP_MIN_ADDRESS; })
203
204/*
205 * How many physical pages per kmem arena virtual page.
206 */
207#ifndef VM_KMEM_SIZE_SCALE
208#define	VM_KMEM_SIZE_SCALE	(1)
209#endif
210
211/*
212 * Optional ceiling (in bytes) on the size of the kmem arena: 60% of the
213 * kernel map.
214 */
215#ifndef VM_KMEM_SIZE_MAX
216#define	VM_KMEM_SIZE_MAX	((VM_MAX_KERNEL_ADDRESS - \
217    VM_MIN_KERNEL_ADDRESS + 1) * 3 / 5)
218#endif
219
220/* initial pagein size of beginning of executable file */
221#ifndef VM_INITIAL_PAGEIN
222#define	VM_INITIAL_PAGEIN	16
223#endif
224
225#define	ZERO_REGION_SIZE	(2 * 1024 * 1024)	/* 2MB */
226
227#endif /* _MACHINE_VMPARAM_H_ */
228