1 /*        $NetBSD: vmparam.h,v 1.88 2022/08/21 13:15:15 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/mutex.h>
41 
42 #include <machine/pte.h>
43 
44 /*
45  * Machine dependent constants for 386.
46  */
47 
48 /*
49  * Page size on the IA-32 is not variable in the traditional sense.
50  * We override the PAGE_* definitions to compile-time constants.
51  */
52 #define   PAGE_SHIFT          12
53 #define   PAGE_SIZE (1 << PAGE_SHIFT)
54 #define   PAGE_MASK (PAGE_SIZE - 1)
55 
56 /*
57  * Virtual address space arrangement. On 386, both user and kernel
58  * share the address space, not unlike the vax.
59  * USRSTACK is the top (end) of the user stack. Immediately above the
60  * user stack is the page table map, and then kernel address space.
61  */
62 #define   USRSTACK  VM_MAXUSER_ADDRESS
63 
64 /*
65  * Virtual memory related constants, all in bytes
66  */
67 #define   MAXTSIZ             (256*1024*1024)               /* max text size */
68 #ifndef DFLDSIZ
69 #define   DFLDSIZ             (256*1024*1024)               /* initial data size limit */
70 #endif
71 #ifndef MAXDSIZ
72 #define   MAXDSIZ             (3U*1024*1024*1024) /* 3G max data size */
73 #endif
74 #ifndef MAXDSIZ_BU
75 #define   MAXDSIZ_BU          (2U*1024*1024*1024 +          /* 2.5G max data size for */ \
76                                1U* 512*1024*1024) /* bottom-up allocation */ \
77                                                             /* could be a bit more */
78 #endif
79 #ifndef   DFLSSIZ
80 #define   DFLSSIZ             (2*1024*1024)                 /* initial stack size limit */
81 #endif
82 #ifndef   MAXSSIZ
83 #define   MAXSSIZ             (64*1024*1024)                /* max stack size */
84 #endif
85 
86 /*
87  * IA-32 can't do per-page execute permission, so instead we implement
88  * two executable segments for %cs, one that covers everything and one
89  * that excludes some of the address space (currently just the stack).
90  * I386_MAX_EXE_ADDR is the upper boundary for the smaller segment.
91  */
92 #define I386_MAX_EXE_ADDR     (USRSTACK - MAXSSIZ)
93 
94 /*
95  * Size of User Raw I/O map
96  */
97 #define   USRIOSIZE           300
98 
99 /*
100  * See pmap_private.h for details.
101  */
102 #ifdef PAE
103 #define L2_SLOT_PTE (KERNBASE/NBPD_L2-4) /* 1532: for recursive PDP map */
104 #define L2_SLOT_KERN          (KERNBASE/NBPD_L2)   /* 1536: start of kernel space */
105 #else /* PAE */
106 #define L2_SLOT_PTE (KERNBASE/NBPD_L2-1) /* 767: for recursive PDP map */
107 #define L2_SLOT_KERN          (KERNBASE/NBPD_L2)   /* 768: start of kernel space */
108 #endif /* PAE */
109 
110 #define L2_SLOT_KERNBASE L2_SLOT_KERN
111 
112 #define PDIR_SLOT_KERN        L2_SLOT_KERN
113 #define PDIR_SLOT_PTE         L2_SLOT_PTE
114 
115 /* size of a PDP: usually one page, except for PAE */
116 #ifdef PAE
117 #define PDP_SIZE 4
118 #else
119 #define PDP_SIZE 1
120 #endif
121 
122 /* largest value (-1 for APTP space) */
123 #define NKL2_MAX_ENTRIES      (NTOPLEVEL_PDES - (KERNBASE/NBPD_L2) - 1)
124 #define NKL1_MAX_ENTRIES      (unsigned long)(NKL2_MAX_ENTRIES * NPDPG)
125 
126 #define NKL2_KIMG_ENTRIES     0         /* XXX unused */
127 
128 #define NKL2_START_ENTRIES    0         /* XXX computed on runtime */
129 #define NKL1_START_ENTRIES    0         /* XXX unused */
130 
131 #ifndef XENPV
132 #define NTOPLEVEL_PDES                  (PAGE_SIZE * PDP_SIZE / (sizeof (pd_entry_t)))
133 #else     /* !XENPV */
134 #ifdef  PAE
135 #define NTOPLEVEL_PDES                  1964      /* 1964-2047 reserved by Xen */
136 #else     /* PAE */
137 #define NTOPLEVEL_PDES                  1008      /* 1008-1023 reserved by Xen */
138 #endif    /* PAE */
139 #endif  /* !XENPV */
140 
141 /*
142  * Mach derived constants
143  */
144 
145 /* user/kernel map constants */
146 #define VM_MIN_ADDRESS                  ((vaddr_t)0)
147 #define   VM_MAXUSER_ADDRESS  ((vaddr_t)(PDIR_SLOT_PTE << L2_SHIFT) - PAGE_SIZE)
148 #define   VM_MAX_ADDRESS                \
149           ((vaddr_t)((PDIR_SLOT_PTE << L2_SHIFT) + (PDIR_SLOT_PTE << L1_SHIFT)))
150 #define   VM_MIN_KERNEL_ADDRESS         ((vaddr_t)(PDIR_SLOT_KERN << L2_SHIFT))
151 #define   VM_MAX_KERNEL_ADDRESS         ((vaddr_t)((PDIR_SLOT_KERN + NKL2_MAX_ENTRIES) << L2_SHIFT))
152 
153 /*
154  * The address to which unspecified mapping requests default
155  */
156 #ifdef _KERNEL_OPT
157 #include "opt_uvm.h"
158 #include "opt_xen.h"
159 #endif
160 #define __USE_TOPDOWN_VM
161 #define VM_DEFAULT_ADDRESS_BOTTOMUP(da, sz) \
162     round_page((vaddr_t)(da) + (vsize_t)MIN(maxdmap, MAXDSIZ_BU))
163 
164 /* virtual sizes (bytes) for various kernel submaps */
165 #define VM_PHYS_SIZE                    (USRIOSIZE*PAGE_SIZE)
166 
167 #define VM_PHYSSEG_STRAT      VM_PSTRAT_BIGFIRST
168 
169 #ifdef XENPV
170 #define   VM_PHYSSEG_MAX                1
171 #define   VM_NFREELIST                  1
172 #else
173 #define   VM_PHYSSEG_MAX                32        /* 1 "hole" + 31 free lists */
174 #define   VM_NFREELIST                  4
175 #define   VM_FREELIST_FIRST16 3
176 #define   VM_FREELIST_FIRST1G 2
177 #define   VM_FREELIST_FIRST4G 1
178 #endif /* XENPV */
179 #define   VM_FREELIST_DEFAULT 0
180 
181 #endif /* _I386_VMPARAM_H_ */
182