Annotation of sys/sys/param.h, Revision 1.1.1.1
1.1 nbrk 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 */
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