|
|
1.1 root 1: /*-
2: * Copyright (c) 1982, 1986, 1989 The Regents of the University of California.
3: * All rights reserved.
4: *
5: * Redistribution and use in source and binary forms, with or without
6: * modification, are permitted provided that the following conditions
7: * are met:
8: * 1. Redistributions of source code must retain the above copyright
9: * notice, this list of conditions and the following disclaimer.
10: * 2. Redistributions in binary form must reproduce the above copyright
11: * notice, this list of conditions and the following disclaimer in the
12: * documentation and/or other materials provided with the distribution.
13: * 3. All advertising materials mentioning features or use of this software
14: * must display the following acknowledgement:
15: * This product includes software developed by the University of
16: * California, Berkeley and its contributors.
17: * 4. Neither the name of the University nor the names of its contributors
18: * may be used to endorse or promote products derived from this software
19: * without specific prior written permission.
20: *
21: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31: * SUCH DAMAGE.
32: *
33: * @(#)param.h 7.23 (Berkeley) 5/6/91
34: */
35:
36: #define BSD 199103 /* March, 1991 system version (year & month) */
37: #define BSD4_3 1
38: #define BSD4_4 0.5
39:
40: #ifndef NULL
41: #define NULL 0
42: #endif
43:
44: #ifndef LOCORE
45: #include <sys/types.h>
46: #endif
47:
48: /*
49: * Machine-independent constants (some used in following include files).
50: * Redefined constants are from POSIX 1003.1 limits file.
51: *
52: * MAXCOMLEN should be >= sizeof(ac_comm) (see <acct.h>)
53: * MAXLOGNAME should be >= UT_NAMESIZE (see <utmp.h>)
54: */
55: #include <sys/syslimits.h>
56:
57: #define MAXCOMLEN 16 /* max command name remembered */
58: #define MAXINTERP 32 /* max interpreter file name length */
59: #define MAXLOGNAME 12 /* max login name length */
60: #define MAXUPRC CHILD_MAX /* max simultaneous processes */
61: #define NCARGS ARG_MAX /* max bytes for an exec function */
62: #define NGROUPS NGROUPS_MAX /* max number groups */
63: #define NOFILE OPEN_MAX /* max open files per process */
64: #define NOGROUP 65535 /* marker for empty group set member */
65: #define MAXHOSTNAMELEN 256 /* max hostname size */
66:
67: /* More types and definitions used throughout the kernel. */
68: #ifdef KERNEL
69: #include <sys/cdefs.h>
70: #include <sys/errno.h>
71: #include <sys/time.h>
72: #include <sys/resource.h>
73: #include <sys/ucred.h>
74: #include <sys/uio.h>
75: #endif
76:
77: /* Signals. */
78: #include <sys/signal.h>
79:
80: /* Machine type dependent parameters. */
81: #include <machine/param.h>
82: #include <machine/endian.h>
83: #include <machine/limits.h>
84:
85: /*
86: * Priorities. Note that with 32 run queues, differences less than 4 are
87: * insignificant.
88: */
89: #define PSWP 0
90: #define PVM 4
91: #define PINOD 8
92: #define PRIBIO 16
93: #define PVFS 20
94: #define PZERO 22 /* No longer magic, shouldn't be here. XXX */
95: #define PSOCK 24
96: #define PWAIT 32
97: #define PLOCK 36
98: #define PPAUSE 40
99: #define PUSER 50
100: #define MAXPRI 127 /* Priorities range from 0 through MAXPRI. */
101:
102: #define PRIMASK 0x0ff
103: #define PCATCH 0x100 /* OR'd with pri for tsleep to check signals */
104:
105: #define NZERO 0 /* default "nice" */
106:
107: #define NBPW sizeof(int) /* number of bytes per word (integer) */
108:
109: #define CMASK 022 /* default file mask: S_IWGRP|S_IWOTH */
110: #define NODEV (dev_t)(-1) /* non-existent device */
111:
112: /*
113: * Clustering of hardware pages on machines with ridiculously small
114: * page sizes is done here. The paging subsystem deals with units of
115: * CLSIZE pte's describing NBPG (from machine/machparam.h) pages each.
116: */
117: #define CLBYTES (CLSIZE*NBPG)
118: #define CLOFSET (CLSIZE*NBPG-1) /* for clusters, like PGOFSET */
119: #define claligned(x) ((((int)(x))&CLOFSET)==0)
120: #define CLOFF CLOFSET
121: #define CLSHIFT (PGSHIFT+CLSIZELOG2)
122:
123: #if CLSIZE==1
124: #define clbase(i) (i)
125: #define clrnd(i) (i)
126: #else
127: /* Give the base virtual address (first of CLSIZE). */
128: #define clbase(i) ((i) &~ (CLSIZE-1))
129: /* Round a number of clicks up to a whole cluster. */
130: #define clrnd(i) (((i) + (CLSIZE-1)) &~ (CLSIZE-1))
131: #endif
132:
133: #define CBLOCK 64 /* Clist block size, must be a power of 2. */
134: #define CBQSIZE (CBLOCK/NBBY) /* Quote bytes/cblock - can do better. */
135: /* Data chars/clist. */
136: #define CBSIZE (CBLOCK - sizeof(struct cblock *) - CBQSIZE)
137: #define CROUND (CBLOCK - 1) /* Clist rounding. */
138:
139: /*
140: * File system parameters and macros.
141: *
142: * The file system is made out of blocks of at most MAXBSIZE units, with
143: * smaller units (fragments) only in the last direct block. MAXBSIZE
144: * primarily determines the size of buffers in the buffer pool. It may be
145: * made larger without any effect on existing file systems; however making
146: * it smaller make make some file systems unmountable.
147: */
148: #define MAXBSIZE 8192
149: #define MAXFRAG 8
150:
151: /*
152: * MAXPATHLEN defines the longest permissable path length after expanding
153: * symbolic links. It is used to allocate a temporary buffer from the buffer
154: * pool in which to do the name expansion, hence should be a power of two,
155: * and must be less than or equal to MAXBSIZE. MAXSYMLINKS defines the
156: * maximum number of symbolic links that may be expanded in a path name.
157: * It should be set high enough to allow all legitimate uses, but halt
158: * infinite loops reasonably quickly.
159: */
160: #define MAXPATHLEN PATH_MAX
161: #define MAXSYMLINKS 8
162:
163: /* Bit map related macros. */
164: #define setbit(a,i) ((a)[(i)/NBBY] |= 1<<((i)%NBBY))
165: #define clrbit(a,i) ((a)[(i)/NBBY] &= ~(1<<((i)%NBBY)))
166: #define isset(a,i) ((a)[(i)/NBBY] & (1<<((i)%NBBY)))
167: #define isclr(a,i) (((a)[(i)/NBBY] & (1<<((i)%NBBY))) == 0)
168:
169: /* Macros for counting and rounding. */
170: #ifndef howmany
171: #define howmany(x, y) (((x)+((y)-1))/(y))
172: #endif
173: #define roundup(x, y) ((((x)+((y)-1))/(y))*(y))
174: #define powerof2(x) ((((x)-1)&(x))==0)
175:
176: /* Macros for fast min/max: with inline expansion, the "function" is faster. */
177: #ifdef KERNEL
178: #define MIN(a,b) min((a), (b))
179: #define MAX(a,b) max((a), (b))
180: #else
181: #define MIN(a,b) (((a)<(b))?(a):(b))
182: #define MAX(a,b) (((a)>(b))?(a):(b))
183: #endif
184:
185: /*
186: * Constants for setting the parameters of the kernel memory allocator.
187: *
188: * 2 ** MINBUCKET is the smallest unit of memory that will be
189: * allocated. It must be at least large enough to hold a pointer.
190: *
191: * Units of memory less or equal to MAXALLOCSAVE will permanently
192: * allocate physical memory; requests for these size pieces of
193: * memory are quite fast. Allocations greater than MAXALLOCSAVE must
194: * always allocate and free physical memory; requests for these
195: * size allocations should be done infrequently as they will be slow.
196: *
197: * Constraints: CLBYTES <= MAXALLOCSAVE <= 2 ** (MINBUCKET + 14), and
198: * MAXALLOCSIZE must be a power of two.
199: */
200: #define MINBUCKET 4 /* 4 => min allocation of 16 bytes */
201: #define MAXALLOCSAVE (2 * CLBYTES)
202:
203: /*
204: * Scale factor for scaled integers used to count %cpu time and load avgs.
205: *
206: * The number of CPU `tick's that map to a unique `%age' can be expressed
207: * by the formula (1 / (2 ^ (FSHIFT - 11))). The maximum load average that
208: * can be calculated (assuming 32 bits) can be closely approximated using
209: * the formula (2 ^ (2 * (16 - FSHIFT))) for (FSHIFT < 15).
210: *
211: * For the scheduler to maintain a 1:1 mapping of CPU `tick' to `%age',
212: * FSHIFT must be at least 11; this gives us a maximum load avg of ~1024.
213: */
214: #define FSHIFT 11 /* bits to right of fixed binary point */
215: #define FSCALE (1<<FSHIFT)
This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.