1 /* $OpenBSD: param.h,v 1.72 2007/07/25 20:07:28 deraadt Exp $ */
2 /* $NetBSD: param.h,v 1.23 1996/03/17 01:02:29 thorpej Exp $ */
3
4 /*-
5 * Copyright (c) 1982, 1986, 1989, 1993
6 * The Regents of the University of California. All rights reserved.
7 * (c) UNIX System Laboratories, Inc.
8 * All or some portions of this file are derived from material licensed
9 * to the University of California by American Telephone and Telegraph
10 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
11 * the permission of UNIX System Laboratories, Inc.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 * @(#)param.h 8.2 (Berkeley) 1/21/94
38 */
39
40 #define BSD 199306 /* System version (year & month). */
41 #define BSD4_3 1
42 #define BSD4_4 1
43
44 #define OpenBSD 200711 /* OpenBSD version (year & month). */
45 #define OpenBSD4_2 1 /* OpenBSD 4.2 */
46
47 #ifndef NULL
48 #ifdef __GNUG__
49 #define NULL __null
50 #else
51 #define NULL 0L
52 #endif
53 #endif
54
55 #ifndef _LOCORE
56 #include <sys/types.h>
57 #include <sys/simplelock.h>
58 #endif
59
60 /*
61 * Machine-independent constants (some used in following include files).
62 * Redefined constants are from POSIX 1003.1 limits file.
63 *
64 * MAXCOMLEN should be >= sizeof(ac_comm) (see <acct.h>)
65 * MAXLOGNAME should be >= UT_NAMESIZE (see <utmp.h>)
66 */
67 #include <sys/syslimits.h>
68
69 #define MAXCOMLEN 16 /* max command name remembered */
70 #define MAXINTERP 64 /* max interpreter file name length */
71 #define MAXLOGNAME LOGIN_NAME_MAX /* max login name length w/ NUL */
72 #define MAXUPRC CHILD_MAX /* max simultaneous processes */
73 #define NCARGS ARG_MAX /* max bytes for an exec function */
74 #define NGROUPS NGROUPS_MAX /* max number groups */
75 #define NOFILE OPEN_MAX /* max open files per process (soft) */
76 #define NOFILE_MAX 1024 /* max open files per process (hard) */
77 #define NOGROUP 65535 /* marker for empty group set member */
78 #define MAXHOSTNAMELEN 256 /* max hostname size */
79
80 /* More types and definitions used throughout the kernel. */
81 #ifdef _KERNEL
82 #include <sys/cdefs.h>
83 #include <sys/errno.h>
84 #include <sys/time.h>
85 #include <sys/resource.h>
86 #include <sys/ucred.h>
87 #include <sys/uio.h>
88 #endif
89
90 /* Signals. */
91 #include <sys/signal.h>
92
93 /* Machine type dependent parameters. */
94 #include <sys/limits.h>
95 #include <machine/param.h>
96
97 /*
98 * Priorities. Note that with 32 run queues, differences less than 4 are
99 * insignificant.
100 */
101 #define PSWP 0
102 #define PVM 4
103 #define PINOD 8
104 #define PRIBIO 16
105 #define PVFS 20
106 #define PZERO 22 /* No longer magic, shouldn't be here. XXX */
107 #define PSOCK 24
108 #define PWAIT 32
109 #define PLOCK 36
110 #define PPAUSE 40
111 #define PUSER 50
112 #define MAXPRI 127 /* Priorities range from 0 through MAXPRI. */
113
114 #define PRIMASK 0x0ff
115 #define PCATCH 0x100 /* OR'd with pri for tsleep to check signals */
116 #define PNORELOCK 0x200 /* OR'd with pri for ltsleep to not relock
117 the interlock */
118
119 #define NBPW sizeof(int) /* number of bytes per word (integer) */
120
121 #define CMASK 022 /* default file mask: S_IWGRP|S_IWOTH */
122 #define NODEV (dev_t)(-1) /* non-existent device */
123 #define NETDEV (dev_t)(-2) /* network device (for nfs swap) */
124
125 #define CBLOCK 64 /* Clist block size, must be a power of 2. */
126 #define CBQSIZE (CBLOCK/NBBY) /* Quote bytes/cblock - can do better. */
127 /* Data chars/clist. */
128 #define CBSIZE (CBLOCK - sizeof(struct cblock *) - CBQSIZE)
129 #define CROUND (CBLOCK - 1) /* Clist rounding. */
130
131 /*
132 * Constants related to network buffer management.
133 * MCLBYTES must be no larger than NBPG (the software page size), and,
134 * on machines that exchange pages of input or output buffers with mbuf
135 * clusters (MAPPED_MBUFS), MCLBYTES must also be an integral multiple
136 * of the hardware page size.
137 */
138 #define MSIZE 256 /* size of an mbuf */
139 #define MCLSHIFT 11 /* convert bytes to m_buf clusters */
140 /* 2K cluster can hold Ether frame */
141 #define MCLBYTES (1 << MCLSHIFT) /* size of a m_buf cluster */
142 #define MCLOFSET (MCLBYTES - 1)
143
144
145 /*
146 * File system parameters and macros.
147 *
148 * The file system is made out of blocks of at most MAXBSIZE units, with
149 * smaller units (fragments) only in the last direct block. MAXBSIZE
150 * primarily determines the size of buffers in the buffer pool. It may be
151 * made larger without any effect on existing file systems; however making
152 * it smaller makes some file systems unmountable.
153 */
154 #ifndef MAXBSIZE /* XXX temp until sun3 DMA chaining */
155 #define MAXBSIZE MAXPHYS
156 #endif
157 #define MAXFRAG 8
158
159 /*
160 * MAXPATHLEN defines the longest permissible path length after expanding
161 * symbolic links. It is used to allocate a temporary buffer from the buffer
162 * pool in which to do the name expansion, hence should be a power of two,
163 * and must be less than or equal to MAXBSIZE. MAXSYMLINKS defines the
164 * maximum number of symbolic links that may be expanded in a path name.
165 * It should be set high enough to allow all legitimate uses, but halt
166 * infinite loops reasonably quickly.
167 */
168 #define MAXPATHLEN PATH_MAX
169 #define MAXSYMLINKS SYMLOOP_MAX
170
171 /* Macros to set/clear/test flags. */
172 #ifdef _KERNEL
173 #define SET(t, f) ((t) |= (f))
174 #define CLR(t, f) ((t) &= ~(f))
175 #define ISSET(t, f) ((t) & (f))
176 #endif
177
178 /* Bit map related macros. */
179 #define setbit(a,i) ((a)[(i)>>3] |= 1<<((i)&(NBBY-1)))
180 #define clrbit(a,i) ((a)[(i)>>3] &= ~(1<<((i)&(NBBY-1))))
181 #define isset(a,i) ((a)[(i)>>3] & (1<<((i)&(NBBY-1))))
182 #define isclr(a,i) (((a)[(i)>>3] & (1<<((i)&(NBBY-1)))) == 0)
183
184 /* Macros for counting and rounding. */
185 #ifndef howmany
186 #define howmany(x, y) (((x)+((y)-1))/(y))
187 #endif
188 #define roundup(x, y) ((((x)+((y)-1))/(y))*(y))
189 #define powerof2(x) ((((x)-1)&(x))==0)
190
191 /* Macros for min/max. */
192 #define MIN(a,b) (((a)<(b))?(a):(b))
193 #define MAX(a,b) (((a)>(b))?(a):(b))
194
195 /* Macros for calculating the offset of a field */
196 #if !defined(offsetof) && defined(_KERNEL)
197 #define offsetof(s, e) ((size_t)&((s *)0)->e)
198 #endif
199
200 /*
201 * Constants for setting the parameters of the kernel memory allocator.
202 *
203 * 2 ** MINBUCKET is the smallest unit of memory that will be
204 * allocated. It must be at least large enough to hold a pointer.
205 *
206 * Units of memory less or equal to MAXALLOCSAVE will permanently
207 * allocate physical memory; requests for these size pieces of
208 * memory are quite fast. Allocations greater than MAXALLOCSAVE must
209 * always allocate and free physical memory; requests for these
210 * size allocations should be done infrequently as they will be slow.
211 *
212 * Constraints: PAGE_SIZE <= MAXALLOCSAVE <= 2 ** (MINBUCKET + 14), and
213 * MAXALLOCSIZE must be a power of two.
214 */
215 #define MINBUCKET 4 /* 4 => min allocation of 16 bytes */
216 #define MAXALLOCSAVE (2 * PAGE_SIZE)
217
218 /*
219 * Scale factor for scaled integers used to count %cpu time and load avgs.
220 *
221 * The number of CPU `tick's that map to a unique `%age' can be expressed
222 * by the formula (1 / (2 ^ (FSHIFT - 11))). The maximum load average that
223 * can be calculated (assuming 32 bits) can be closely approximated using
224 * the formula (2 ^ (2 * (16 - FSHIFT))) for (FSHIFT < 15).
225 *
226 * For the scheduler to maintain a 1:1 mapping of CPU `tick' to `%age',
227 * FSHIFT must be at least 11; this gives us a maximum load avg of ~1024.
228 */
229 #define FSHIFT 11 /* bits to right of fixed binary point */
230 #define FSCALE (1<<FSHIFT)
231
232 /*
233 * The time for a process to be blocked before being very swappable.
234 * This is a number of seconds which the system takes as being a non-trivial
235 * amount of real time. You probably shouldn't change this;
236 * it is used in subtle ways (fractions and multiples of it are, that is, like
237 * half of a ``long time'', almost a long time, etc.)
238 * It is related to human patience and other factors which don't really
239 * change over time.
240 */
241 #define MAXSLP 20
242
243 /*
244 * rfork() options.
245 *
246 * XXX currently, operations without RFPROC set are not supported.
247 */
248 #define RFNAMEG (1<<0) /* UNIMPL new plan9 `name space' */
249 #define RFENVG (1<<1) /* UNIMPL copy plan9 `env space' */
250 #define RFFDG (1<<2) /* copy fd table */
251 #define RFNOTEG (1<<3) /* UNIMPL create new plan9 `note group' */
252 #define RFPROC (1<<4) /* change child (else changes curproc) */
253 #define RFMEM (1<<5) /* share `address space' */
254 #define RFNOWAIT (1<<6) /* parent need not wait() on child */
255 #define RFCNAMEG (1<<10) /* UNIMPL zero plan9 `name space' */
256 #define RFCENVG (1<<11) /* UNIMPL zero plan9 `env space' */
257 #define RFCFDG (1<<12) /* zero fd table */
258 #define RFTHREAD (1<<13) /* create a thread, not a process */