1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*      Copyright (c) 1988 AT&T     */
  22 /*        All Rights Reserved   */
  23 /*
  24  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  25  * Use is subject to license terms.
  26  */
  27 
  28 #ifndef _SYS_VM_MACHPARAM_H
  29 #define _SYS_VM_MACHPARAM_H
  30 
  31 #pragma ident   "%Z%%M% %I%     %E% SMI"
  32 
  33 #ifdef  __cplusplus
  34 extern "C" {
  35 #endif
  36 
  37 /*
  38  * Machine dependent constants for PC.
  39  */
  40 
  41 /*
  42  * USRTEXT is the start of the user text/data space.
  43  */
  44 #define USRTEXT         USRSTACK
  45 
  46 /*
  47  * Virtual memory related constants for UNIX resource control, all in bytes.
  48  * The default stack size (initial stack size limit) keeps the stack from
  49  * taking more than 2 page directory entries in addition to the part of
  50  * the page directory entry which also maps the initial text and data,
  51  * and makes the default slightly bigger than the 8MB on SPARC.
  52  */
  53 #ifdef __amd64
  54 /*
  55  * On amd64, the stack grows down from just below KERNELBASE (see the
  56  * definition of USERLIMIT in i86pc/sys/machparam.h). Theoretically,
  57  * it could grow down to the top of the VA hole (0xffff800000000000),
  58  * giving it a possible maximum of about 125T. For an amd64 xpv
  59  * kernel, all user VA space is below the VA hole. The theoretical
  60  * maximum for the stack is about the same, although it can't grow
  61  * to quite that size, since it would clash with the heap.
  62  *
  63  * Pick an upper limit that will work in both cases: 32T.
  64  *
  65  * For 32bit processes, the stack is below the text segment.
  66  */
  67 #define MAXSSIZ         (32ULL * 1024ULL * 1024ULL * 1024ULL * 1024ULL)
  68 #else
  69 #define MAXSSIZ         (USRSTACK - 1024*1024)
  70 #endif /* __amd64 */
  71 #define DFLSSIZ         (8*1024*1024 + ((USRSTACK) & 0x3FFFFF))
  72 
  73 /*
  74  * The following are limits beyond which the hard or soft limits for stack
  75  * and data cannot be increased. These may be viewed as fundamental
  76  * characteristics of the system. Note: a bug in SVVS requires that the
  77  * default hard limit be increasable, so the default hard limit must be
  78  * less than these physical limits.
  79  */
  80 #define DSIZE_LIMIT     (USERLIMIT-USRTEXT)     /* physical data limit */
  81 #define SSIZE_LIMIT     (USRSTACK)              /* physical stack limit */
  82 
  83 /*
  84  * Size of the kernel segkmem system pte table.  This virtual
  85  * space is controlled by the resource map "kernelmap".
  86  */
  87 #define SYSPTSIZE       ((61*1024*1024) / MMU_PAGESIZE)
  88 
  89 /*
  90  * Size of the ethernet addressable kernel segkmem system pte table.
  91  * This virtual space is controlled by the resource map "ekernelmap".
  92  * The ethernet interfaces in some sun machines can address only
  93  * the upper 16 Megabytes of memory.  Since the ethernet
  94  * driver kmem_allocs its memory, we bias all kmem_allocs
  95  * to try ekernelmap first and if it fails try kernelmap.
  96  * Folks that allocate directly out of kernelmap, above,
  97  * get memory that is non-ethernet addressable.
  98  */
  99 #define E_SYSPTSIZE     (0x2000000 / MMU_PAGESIZE)
 100 
 101 /*
 102  * The virtual address space to be used by the seg_map segment
 103  * driver for fast kernel mappings.
 104  */
 105 #if defined(__i386)
 106 #define SEGMAPDEFAULT   (16 * 1024 * 1024)
 107 #define SEGMAPMAX       (128 * 1024 * 1024)
 108 #else
 109 #define SEGMAPDEFAULT   (64 * 1024 * 1024)
 110 #endif
 111 
 112 /*
 113  * The time for a process to be blocked before being very swappable.
 114  * This is a number of seconds which the system takes as being a non-trivial
 115  * amount of real time. You probably shouldn't change this;
 116  * it is used in subtle ways (fractions and multiples of it are, that is, like
 117  * half of a ``long time'', almost a long time, etc.)
 118  * It is related to human patience and other factors which don't really
 119  * change over time.
 120  */
 121 #define MAXSLP          20
 122 
 123 /*
 124  * A swapped in process is given a small amount of core without being bothered
 125  * by the page replacement algorithm. Basically this says that if you are
 126  * swapped in you deserve some resources. We protect the last SAFERSS
 127  * pages against paging and will just swap you out rather than paging you.
 128  * Note that each process has at least UPAGES pages which are not
 129  * paged anyways so this number just means a swapped in process is
 130  * given around 32k bytes.
 131  */
 132 /*
 133  * nominal ``small'' resident set size
 134  * protected against replacement
 135  */
 136 #define SAFERSS         3
 137 
 138 /*
 139  * DISKRPM is used to estimate the number of paging i/o operations
 140  * which one can expect from a single disk controller.
 141  *
 142  * XXX - The system doesn't account for multiple swap devices.
 143  */
 144 #define DISKRPM         60
 145 
 146 /*
 147  * The maximum value for handspreadpages which is the the distance
 148  * between the two clock hands in pages.
 149  */
 150 #define MAXHANDSPREADPAGES      ((64 * 1024 * 1024) / PAGESIZE)
 151 
 152 /*
 153  * Paged text files that are less than PGTHRESH bytes
 154  * may be "prefaulted in" instead of demand paged.
 155  */
 156 #define PGTHRESH        (280 * 1024)
 157 
 158 #ifdef  __cplusplus
 159 }
 160 #endif
 161 
 162 #endif  /* _SYS_VM_MACHPARAM_H */