xref: /original-bsd/sys/hp300/include/vmparam.h (revision 6d57652c)
1 /*
2  * Copyright (c) 1988 University of Utah.
3  * Copyright (c) 1982, 1986, 1990 The Regents of the University of California.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * the Systems Programming Group of the University of Utah Computer
8  * Science Department.
9  *
10  * %sccs.include.redist.c%
11  *
12  * from: Utah $Hdr: vmparam.h 1.14 89/08/14$
13  *
14  *	@(#)vmparam.h	7.2 (Berkeley) 12/05/90
15  */
16 
17 /*
18  * Machine dependent constants for HP300
19  */
20 /*
21  * USRTEXT is the start of the user text/data space, while USRSTACK
22  * is the top (end) of the user stack.  LOWPAGES and HIGHPAGES are
23  * the number of pages from the beginning of the P0 region to the
24  * beginning of the text and from the beginning of the P1 region to the
25  * beginning of the stack respectively.
26  *
27  * NOTE: the ONLY reason that HIGHPAGES is 0x100 instead of UPAGES (3)
28  * is for HPUX compatibility.  Why??  Because HPUX's debuggers
29  * have the user's stack hard-wired at FFF00000 for post-mortems,
30  * and we must be compatible...
31  */
32 #define	USRTEXT		0
33 #define	USRSTACK	(-HIGHPAGES*NBPG)	/* Start of user stack */
34 #define	BTOPUSRSTACK	(0x100000-HIGHPAGES)	/* btop(USRSTACK) */
35 #define P1PAGES		0x100000
36 #define	LOWPAGES	0
37 #define HIGHPAGES	(0x100000/NBPG)
38 
39 /*
40  * Virtual memory related constants, all in bytes
41  */
42 #ifndef MAXTSIZ
43 #define	MAXTSIZ		(6*1024*1024)		/* max text size */
44 #endif
45 #ifndef DFLDSIZ
46 #define	DFLDSIZ		(8*1024*1024)		/* initial data size limit */
47 #endif
48 #ifndef MAXDSIZ
49 #define	MAXDSIZ		(16*1024*1024)		/* max data size */
50 #endif
51 #ifndef	DFLSSIZ
52 #define	DFLSSIZ		(512*1024)		/* initial stack size limit */
53 #endif
54 #ifndef	MAXSSIZ
55 #define	MAXSSIZ		MAXDSIZ			/* max stack size */
56 #endif
57 
58 /*
59  * Default sizes of swap allocation chunks (see dmap.h).
60  * The actual values may be changed in vminit() based on MAXDSIZ.
61  * With MAXDSIZ of 16Mb and NDMAP of 38, dmmax will be 1024.
62  * DMMIN should be at least ctod(1) so that vtod() works.
63  * vminit() insures this.
64  */
65 #define	DMMIN	32			/* smallest swap allocation */
66 #define	DMMAX	4096			/* largest potential swap allocation */
67 #define	DMTEXT	1024			/* swap allocation for text */
68 
69 /*
70  * Sizes of the system and user portions of the system page table.
71  */
72 /* SYSPTSIZE IS SILLY; IT SHOULD BE COMPUTED AT BOOT TIME */
73 #define	SYSPTSIZE	(2 * NPTEPG)
74 #define	USRPTSIZE 	(1 * NPTEPG)
75 
76 /*
77  * PTEs for mapping user space into kernel for phyio operations.
78  * One page is enough to handle 4Mb of simultaneous raw IO operations.
79  */
80 #define USRIOSIZE	(1 * NPTEPG)
81 
82 /*
83  * PTEs for system V style shared memory.
84  * This is basically slop for kmempt which we actually allocate (malloc) from.
85  */
86 #define SHMMAXPGS	1024
87 
88 /*
89  * Boundary at which to place first MAPMEM segment if not explicitly
90  * specified.  Should be a power of two.  This allows some slop for
91  * the data segment to grow underneath the first mapped segment.
92  */
93 #define MMSEG		0x200000
94 
95 /*
96  * The size of the clock loop.
97  */
98 #define	LOOPPAGES	(maxfree - firstfree)
99 
100 /*
101  * The time for a process to be blocked before being very swappable.
102  * This is a number of seconds which the system takes as being a non-trivial
103  * amount of real time.  You probably shouldn't change this;
104  * it is used in subtle ways (fractions and multiples of it are, that is, like
105  * half of a ``long time'', almost a long time, etc.)
106  * It is related to human patience and other factors which don't really
107  * change over time.
108  */
109 #define	MAXSLP 		20
110 
111 /*
112  * A swapped in process is given a small amount of core without being bothered
113  * by the page replacement algorithm.  Basically this says that if you are
114  * swapped in you deserve some resources.  We protect the last SAFERSS
115  * pages against paging and will just swap you out rather than paging you.
116  * Note that each process has at least UPAGES+CLSIZE pages which are not
117  * paged anyways (this is currently 8+2=10 pages or 5k bytes), so this
118  * number just means a swapped in process is given around 25k bytes.
119  * Just for fun: current memory prices are 4600$ a megabyte on VAX (4/22/81),
120  * so we loan each swapped in process memory worth 100$, or just admit
121  * that we don't consider it worthwhile and swap it out to disk which costs
122  * $30/mb or about $0.75.
123  */
124 #define	SAFERSS		4		/* nominal ``small'' resident set size
125 					   protected against replacement */
126 
127 /*
128  * DISKRPM is used to estimate the number of paging i/o operations
129  * which one can expect from a single disk controller.
130  */
131 #define	DISKRPM		60
132 
133 /*
134  * Klustering constants.  Klustering is the gathering
135  * of pages together for pagein/pageout, while clustering
136  * is the treatment of hardware page size as though it were
137  * larger than it really is.
138  *
139  * KLMAX gives maximum cluster size in CLSIZE page (cluster-page)
140  * units.  Note that ctod(KLMAX*CLSIZE) must be <= DMMIN in dmap.h.
141  * ctob(KLMAX) should also be less than MAXPHYS (in vm_swp.c)
142  * unless you like "big push" panics.
143  */
144 
145 #define	KLMAX	(4/CLSIZE)
146 #define	KLSEQL	(2/CLSIZE)		/* in klust if vadvise(VA_SEQL) */
147 #define	KLIN	(4/CLSIZE)		/* default data/stack in klust */
148 #define	KLTXT	(4/CLSIZE)		/* default text in klust */
149 #define	KLOUT	(4/CLSIZE)
150 
151 /*
152  * KLSDIST is the advance or retard of the fifo reclaim for sequential
153  * processes data space.
154  */
155 #define	KLSDIST	3		/* klusters advance/retard for seq. fifo */
156 
157 /*
158  * Paging thresholds (see vm_sched.c).
159  * Strategy of 1/19/85:
160  *	lotsfree is 512k bytes, but at most 1/4 of memory
161  *	desfree is 200k bytes, but at most 1/8 of memory
162  *	minfree is 64k bytes, but at most 1/2 of desfree
163  */
164 #define	LOTSFREE	(512 * 1024)
165 #define	LOTSFREEFRACT	4
166 #define	DESFREE		(200 * 1024)
167 #define	DESFREEFRACT	8
168 #define	MINFREE		(64 * 1024)
169 #define	MINFREEFRACT	2
170 
171 /*
172  * There are two clock hands, initially separated by HANDSPREAD bytes
173  * (but at most all of user memory).  The amount of time to reclaim
174  * a page once the pageout process examines it increases with this
175  * distance and decreases as the scan rate rises.
176  */
177 #define	HANDSPREAD	(2 * 1024 * 1024)
178 
179 /*
180  * The number of times per second to recompute the desired paging rate
181  * and poke the pagedaemon.
182  */
183 #define	RATETOSCHEDPAGING	4
184 
185 /*
186  * Believed threshold (in megabytes) for which interleaved
187  * swapping area is desirable.
188  */
189 #define	LOTSOFMEM	2
190 
191 #define	mapin(pte, v, pfnum, prot) \
192 	(*(u_int *)(pte) = ((pfnum) << PGSHIFT) | (prot), TBIS((caddr_t)(v)))
193 
194 /*
195  * Mach derived constants
196  */
197 
198 /* user/kernel map constants */
199 #define VM_MIN_ADDRESS		((vm_offset_t)0)
200 #define VM_MAX_ADDRESS		((vm_offset_t)0xFFF00000)
201 #define VM_MIN_KERNEL_ADDRESS	((vm_offset_t)0)
202 #define VM_MAX_KERNEL_ADDRESS	((vm_offset_t)0xFFFFF000)
203 
204 /* virtual sizes (bytes) for various kernel submaps */
205 #define VM_MBUF_SIZE		(NMBCLUSTERS*MCLBYTES)
206 #define VM_KMEM_SIZE		(NKMEMCLUSTERS*CLBYTES)
207 #define VM_PHYS_SIZE		(USRIOSIZE*CLBYTES)
208 
209 /* # of kernel PT pages (initial only, can grow dynamically) */
210 #define VM_KERNEL_PT_PAGES	((vm_size_t)2)		/* XXX: SYSPTSIZE */
211 
212 /* pcb base */
213 #define	pcbb(p)		((u_int)(p)->p_addr)
214