xref: /netbsd-src/sys/conf/param.c (revision ba65fde2d7fefa7d39838fa5fa855e62bd606b5e)
1 /*	$NetBSD: param.c,v 1.64 2012/06/09 02:31:14 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1980, 1986, 1989 Regents of the University of California.
5  * All rights reserved.
6  * (c) UNIX System Laboratories, Inc.
7  * All or some portions of this file are derived from material licensed
8  * to the University of California by American Telephone and Telegraph
9  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10  * the permission of UNIX System Laboratories, Inc.
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. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)param.c	7.20 (Berkeley) 6/27/91
37  */
38 
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: param.c,v 1.64 2012/06/09 02:31:14 christos Exp $");
41 
42 #include "opt_hz.h"
43 #include "opt_rtc_offset.h"
44 #include "opt_sysv.h"
45 #include "opt_sysvparam.h"
46 #include "opt_multiprocessor.h"
47 
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/socket.h>
51 #include <sys/socketvar.h>
52 #include <sys/proc.h>
53 #include <sys/vnode.h>
54 #include <sys/file.h>
55 #include <sys/callout.h>
56 #include <sys/mbuf.h>
57 #include <ufs/ufs/quota.h>
58 #include <sys/kernel.h>
59 #include <sys/utsname.h>
60 #include <sys/ksem.h>
61 #include <sys/lwp.h>
62 #ifdef SYSVSHM
63 #include <machine/vmparam.h>
64 #include <sys/shm.h>
65 #endif
66 #ifdef SYSVSEM
67 #include <sys/sem.h>
68 #endif
69 #ifdef SYSVMSG
70 #include <sys/msg.h>
71 #endif
72 
73 /*
74  * PCC cannot handle the 80KB string literal.
75  */
76 #if !defined(__PCC__)
77 #define CONFIG_FILE
78 #include "config_file.h"
79 #endif
80 
81 /*
82  * System parameter formulae.
83  *
84  * This file is copied into each directory where we compile
85  * the kernel; it should be modified there to suit local taste
86  * if necessary.
87  *
88  * Compiled with -DHZ=xx -DRTC_OFFSET=x -DMAXUSERS=xx
89  */
90 
91 #ifdef TIMEZONE
92 #error TIMEZONE is an obsolete kernel option.
93 #endif
94 
95 #ifdef DST
96 #error DST is an obsolete kernel option.
97 #endif
98 
99 #ifndef RTC_OFFSET
100 #define RTC_OFFSET 0
101 #endif
102 
103 #ifndef HZ
104 #define	HZ 100
105 #endif
106 
107 #ifndef MAXFILES
108 #define	MAXFILES	(3 * (NPROC + MAXUSERS) + 80)
109 #endif
110 
111 #ifndef MAXEXEC
112 #define	MAXEXEC		16
113 #endif
114 
115 int	hz = HZ;
116 int	tick = 1000000 / HZ;
117 /* can adjust 240ms in 60s */
118 int	tickadj = (240000 / (60 * HZ)) ? (240000 / (60 * HZ)) : 1;
119 int	rtc_offset = RTC_OFFSET;
120 int	maxproc = NPROC;
121 int	maxlwp = MAXLWP;
122 int	desiredvnodes = NVNODE;
123 u_int	maxfiles = MAXFILES;
124 int	fscale = FSCALE;	/* kernel uses `FSCALE', user uses `fscale' */
125 int	maxexec = MAXEXEC;	/* max number of concurrent exec() calls */
126 
127 #ifdef MULTIPROCESSOR
128 u_int	maxcpus = MAXCPUS;
129 size_t	coherency_unit = COHERENCY_UNIT;
130 #else
131 u_int	maxcpus = 1;
132 size_t	coherency_unit = ALIGNBYTES + 1;
133 #endif
134 
135 /*
136  * Various mbuf-related parameters.  These can also be changed at run-time
137  * with sysctl.
138  */
139 int	nmbclusters = 0;
140 
141 #ifndef MBLOWAT
142 #define	MBLOWAT		16
143 #endif
144 int	mblowat = MBLOWAT;
145 
146 #ifndef MCLLOWAT
147 #define	MCLLOWAT	8
148 #endif
149 int	mcllowat = MCLLOWAT;
150 
151 /*
152  * Values in support of System V compatible shared memory.	XXX
153  */
154 #ifdef SYSVSHM
155 #if !defined(SHMMAX) && defined(SHMMAXPGS)
156 #define	SHMMAX	SHMMAXPGS	/* shminit() performs a `*= PAGE_SIZE' */
157 #elif !defined(SHMMAX)
158 #define SHMMAX 0
159 #endif
160 #ifndef	SHMMIN
161 #define	SHMMIN	1
162 #endif
163 #ifndef	SHMMNI
164 #define	SHMMNI	128		/* <64k, see IPCID_TO_IX in ipc.h */
165 #endif
166 #ifndef	SHMSEG
167 #define	SHMSEG	128
168 #endif
169 
170 struct	shminfo shminfo = {
171 	SHMMAX,
172 	SHMMIN,
173 	SHMMNI,
174 	SHMSEG,
175 	0
176 };
177 #endif
178 
179 /*
180  * Values in support of System V compatible semaphores.
181  */
182 #ifdef SYSVSEM
183 struct	seminfo seminfo = {
184 	SEMMAP,		/* # of entries in semaphore map */
185 	SEMMNI,		/* # of semaphore identifiers */
186 	SEMMNS,		/* # of semaphores in system */
187 	SEMMNU,		/* # of undo structures in system */
188 	SEMMSL,		/* max # of semaphores per id */
189 	SEMOPM,		/* max # of operations per semop call */
190 	SEMUME,		/* max # of undo entries per process */
191 	SEMUSZ,		/* size in bytes of undo structure */
192 	SEMVMX,		/* semaphore maximum value */
193 	SEMAEM		/* adjust on exit max value */
194 };
195 #endif
196 
197 /*
198  * Values in support of System V compatible messages.
199  */
200 #ifdef SYSVMSG
201 struct	msginfo msginfo = {
202 	MSGMAX,		/* max chars in a message */
203 	MSGMNI,		/* # of message queue identifiers */
204 	MSGMNB,		/* max chars in a queue */
205 	MSGTQL,		/* max messages in system */
206 	MSGSSZ,		/* size of a message segment */
207 			/* (must be small power of 2 greater than 4) */
208 	MSGSEG		/* number of message segments */
209 };
210 #endif
211 
212 /*
213  * Actual network mbuf sizes (read-only), for netstat.
214  */
215 const	int msize = MSIZE;
216 const	int mclbytes = MCLBYTES;
217 
218 /*
219  * Values in support of POSIX semaphores.
220  */
221 int	ksem_max = KSEM_MAX;
222