xref: /netbsd-src/sys/arch/x68k/include/vmparam.h (revision 2a399c6883d870daece976daec6ffa7bb7f934ce)
1 /*	$NetBSD: vmparam.h,v 1.3 1997/07/12 16:20:50 perry Exp $	*/
2 
3 /*
4  * Copyright (c) 1988 University of Utah.
5  * Copyright (c) 1982, 1986, 1990, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * the Systems Programming Group of the University of Utah Computer
10  * Science Department.
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: Utah $Hdr: vmparam.h 1.16 91/01/18$
41  *
42  *	@(#)vmparam.h	8.2 (Berkeley) 4/19/94
43  */
44 
45 /*
46  * Machine dependent constants for X68K
47  */
48 /*
49  * USRTEXT is the start of the user text/data space, while USRSTACK
50  * is the top (end) of the user stack.  LOWPAGES and HIGHPAGES are
51  * the number of pages from the beginning of the P0 region to the
52  * beginning of the text and from the beginning of the P1 region to the
53  * beginning of the stack respectively.
54  */
55 #define	USRTEXT		8192			/* Must equal __LDPGSZ */
56 #define	USRSTACK	(-HIGHPAGES*NBPG)	/* Start of user stack */
57 #define	BTOPUSRSTACK	(0x100000-HIGHPAGES)	/* btop(USRSTACK) */
58 #define P1PAGES		0x100000
59 #define	LOWPAGES	0
60 #define HIGHPAGES	3			/* UPAGES */
61 
62 /*
63  * Virtual memory related constants, all in bytes
64  */
65 #ifndef MAXTSIZ
66 #define	MAXTSIZ		(8*1024*1024)		/* max text size */
67 #endif
68 #ifndef DFLDSIZ
69 #define	DFLDSIZ		(16*1024*1024)		/* initial data size limit */
70 #endif
71 #ifndef MAXDSIZ
72 #define	MAXDSIZ		(64*1024*1024)		/* max data size */
73 #endif
74 #ifndef	DFLSSIZ
75 #define	DFLSSIZ		(512*1024)		/* initial stack size limit */
76 #endif
77 #ifndef	MAXSSIZ
78 #define	MAXSSIZ		MAXDSIZ			/* max stack size */
79 #endif
80 
81 /*
82  * Sizes of the system and user portions of the system page table.
83  */
84 /* SYSPTSIZE IS SILLY; IT SHOULD BE COMPUTED AT BOOT TIME */
85 #define	SYSPTSIZE	(2 * NPTEPG)	/* 8mb */
86 #define	USRPTSIZE 	(1 * NPTEPG)	/* 4mb */
87 
88 /*
89  * PTEs for mapping user space into the kernel for phyio operations.
90  * One page is enough to handle 4Mb of simultaneous raw IO operations.
91  */
92 #ifndef USRIOSIZE
93 #define USRIOSIZE	(1 * NPTEPG)	/* 4mb */
94 #endif
95 
96 /*
97  * PTEs for system V style shared memory.
98  * This is basically slop for kmempt which we actually allocate (malloc) from.
99  */
100 #ifndef SHMMAXPGS
101 #define SHMMAXPGS	1024		/* 4mb */
102 #endif
103 
104 /*
105  * External IO space map size.
106  */
107 #ifndef EIOMAPSIZE
108 #define EIOMAPSIZE	btoc(0xe0000000-0xc0000000)	/* 32mb */
109 #endif
110 
111 /*
112  * Boundary at which to place first MAPMEM segment if not explicitly
113  * specified.  Should be a power of two.  This allows some slop for
114  * the data segment to grow underneath the first mapped segment.
115  */
116 #define MMSEG		0x200000
117 
118 /*
119  * The size of the clock loop.
120  */
121 #define	LOOPPAGES	(maxfree - firstfree)
122 
123 /*
124  * The time for a process to be blocked before being very swappable.
125  * This is a number of seconds which the system takes as being a non-trivial
126  * amount of real time.  You probably shouldn't change this;
127  * it is used in subtle ways (fractions and multiples of it are, that is, like
128  * half of a ``long time'', almost a long time, etc.)
129  * It is related to human patience and other factors which don't really
130  * change over time.
131  */
132 #define	MAXSLP 		20
133 
134 /*
135  * A swapped in process is given a small amount of core without being bothered
136  * by the page replacement algorithm.  Basically this says that if you are
137  * swapped in you deserve some resources.  We protect the last SAFERSS
138  * pages against paging and will just swap you out rather than paging you.
139  * Note that each process has at least UPAGES+CLSIZE pages which are not
140  * paged anyways (this is currently 8+2=10 pages or 5k bytes), so this
141  * number just means a swapped in process is given around 25k bytes.
142  * Just for fun: current memory prices are 4600$ a megabyte on VAX (4/22/81),
143  * so we loan each swapped in process memory worth 100$, or just admit
144  * that we don't consider it worthwhile and swap it out to disk which costs
145  * $30/mb or about $0.75.
146  * Update: memory prices have changed recently (9/96). At the current
147  * value of $6 per megabyte, we lend each swapped in process memory worth
148  * $0.15, or just admit that we don't consider it worthwhile and swap it out
149  * to disk which costs $0.20/MB, or just under half a cent.
150  */
151 #define	SAFERSS		4		/* nominal ``small'' resident set size
152 					   protected against replacement */
153 
154 /*
155  * DISKRPM is used to estimate the number of paging i/o operations
156  * which one can expect from a single disk controller.
157  */
158 #define	DISKRPM		60
159 
160 /*
161  * Klustering constants.  Klustering is the gathering
162  * of pages together for pagein/pageout, while clustering
163  * is the treatment of hardware page size as though it were
164  * larger than it really is.
165  *
166  * KLMAX gives maximum cluster size in CLSIZE page (cluster-page)
167  * units.  Note that ctod(KLMAX*CLSIZE) must be <= DMMIN in dmap.h.
168  * ctob(KLMAX) should also be less than MAXPHYS (in vm_swp.c)
169  * unless you like "big push" panics.
170  */
171 
172 #define	KLMAX	(4/CLSIZE)
173 #define	KLSEQL	(2/CLSIZE)		/* in klust if vadvise(VA_SEQL) */
174 #define	KLIN	(4/CLSIZE)		/* default data/stack in klust */
175 #define	KLTXT	(4/CLSIZE)		/* default text in klust */
176 #define	KLOUT	(4/CLSIZE)
177 
178 /*
179  * KLSDIST is the advance or retard of the fifo reclaim for sequential
180  * processes data space.
181  */
182 #define	KLSDIST	3		/* klusters advance/retard for seq. fifo */
183 
184 /*
185  * Paging thresholds (see vm_sched.c).
186  * Strategy of 1/19/85:
187  *	lotsfree is 512k bytes, but at most 1/4 of memory
188  *	desfree is 200k bytes, but at most 1/8 of memory
189  */
190 #define	LOTSFREE	(512 * 1024)
191 #define	LOTSFREEFRACT	4
192 #define	DESFREE		(200 * 1024)
193 #define	DESFREEFRACT	8
194 
195 /*
196  * There are two clock hands, initially separated by HANDSPREAD bytes
197  * (but at most all of user memory).  The amount of time to reclaim
198  * a page once the pageout process examines it increases with this
199  * distance and decreases as the scan rate rises.
200  */
201 #define	HANDSPREAD	(2 * 1024 * 1024)
202 
203 /*
204  * The number of times per second to recompute the desired paging rate
205  * and poke the pagedaemon.
206  */
207 #define	RATETOSCHEDPAGING	4
208 
209 /*
210  * Believed threshold (in megabytes) for which interleaved
211  * swapping area is desirable.
212  */
213 #define	LOTSOFMEM	2
214 
215 /*
216  * Mach derived constants
217  */
218 
219 /* user/kernel map constants */
220 #define VM_MIN_ADDRESS		((vm_offset_t)0)
221 #define VM_MAXUSER_ADDRESS	((vm_offset_t)0xFFFFD000)
222 #define VM_MAX_ADDRESS		((vm_offset_t)0xFFFFD000)
223 #define VM_MIN_KERNEL_ADDRESS	((vm_offset_t)0)
224 #define VM_MAX_KERNEL_ADDRESS	((vm_offset_t)0xFFFFF000)
225 
226 /* virtual sizes (bytes) for various kernel submaps */
227 #define VM_MBUF_SIZE		(NMBCLUSTERS*MCLBYTES)
228 #define VM_KMEM_SIZE		(NKMEMCLUSTERS*CLBYTES)
229 #define VM_PHYS_SIZE		(USRIOSIZE*CLBYTES)
230 
231 /* # of kernel PT pages (initial only, can grow dynamically) */
232 #define VM_KERNEL_PT_PAGES	((vm_size_t)2)		/* XXX: SYSPTSIZE */
233 
234 /* pcb base */
235 #define	pcbb(p)		((u_int)(p)->p_addr)
236