1 /*- 2 * Copyright (c) 1982, 1986, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)param.h 8.3 (Berkeley) 4/4/95 39 * $FreeBSD: src/sys/sys/param.h,v 1.61.2.38 2003/05/22 17:12:01 fjoe Exp $ 40 * $DragonFly: src/sys/sys/param.h,v 1.8 2003/10/17 07:30:40 dillon Exp $ 41 */ 42 43 #ifndef _SYS_PARAM_H_ 44 #define _SYS_PARAM_H_ 45 46 #define BSD 199506 /* System version (year & month). */ 47 #define BSD4_3 1 48 #define BSD4_4 1 49 50 /* 51 * __FreeBSD_version numbers are documented in the Porter's Handbook. 52 * If you bump the version for any reason, you should update the documentation 53 * there. 54 * Currently this lives here: 55 * doc/en_US.ISO8859-1/books/porters-handbook/book.sgml 56 */ 57 #undef __FreeBSD_version 58 #define __FreeBSD_version 480101 /* Master, propagated to newvers */ 59 60 #ifndef NULL 61 #define NULL 0 62 #endif 63 64 #ifndef LOCORE 65 #include <sys/types.h> 66 #endif 67 68 /* 69 * Machine-independent constants (some used in following include files). 70 * Redefined constants are from POSIX 1003.1 limits file. 71 * 72 * MAXCOMLEN should be >= sizeof(ac_comm) (see <acct.h>) 73 * MAXLOGNAME should be == UT_NAMESIZE+1 (see <utmp.h>) 74 */ 75 #include <sys/syslimits.h> 76 77 #define MAXCOMLEN 16 /* max command name remembered */ 78 #define MAXINTERP 32 /* max interpreter file name length */ 79 #define MAXLOGNAME 17 /* max login name length (incl. NUL) */ 80 #define MAXUPRC CHILD_MAX /* max simultaneous processes */ 81 #define NCARGS ARG_MAX /* max bytes for an exec function */ 82 #define NGROUPS NGROUPS_MAX /* max number groups */ 83 #define NOFILE OPEN_MAX /* max open files per process */ 84 #define NOGROUP 65535 /* marker for empty group set member */ 85 #define MAXHOSTNAMELEN 256 /* max hostname size */ 86 87 /* More types and definitions used throughout the kernel. */ 88 #ifdef _KERNEL 89 #include <sys/cdefs.h> 90 #include <sys/errno.h> 91 #include <sys/time.h> 92 93 #define FALSE 0 94 #define TRUE 1 95 #endif 96 97 #ifndef _KERNEL 98 /* Signals. */ 99 #include <sys/signal.h> 100 #endif 101 102 /* Machine type dependent parameters. */ 103 #include <machine/param.h> 104 #ifndef _KERNEL 105 #include <machine/limits.h> 106 #endif 107 108 /* 109 * Priorities. Note that with 32 run queues, differences less than 4 are 110 * insignificant. 111 */ 112 #define MAXPRI 127 /* Priorities range from 0 through MAXPRI. */ 113 #define PRIMASK 127 114 #define PRIBASE_REALTIME 0 115 #define PRIBASE_NORMAL 128 116 #define PRIBASE_IDLE 256 117 #define PRIBASE_THREAD 384 /* huh? */ 118 119 #define PCATCH 0x0100 /* OR'd with pri for tsleep to check signals */ 120 #define PUSRFLAG1 0x0200 /* Subsystem specific flag */ 121 122 #define NZERO 0 /* default "nice" */ 123 124 #define NBPW sizeof(int) /* number of bytes per word (integer) */ 125 126 #define CMASK 022 /* default file mask: S_IWGRP|S_IWOTH */ 127 #ifdef _KERNEL 128 #define NODEV (dev_t)(-1) /* non-existent device */ 129 #define NOUDEV (udev_t)(-1) /* non-existent device */ 130 #define NOMAJ 256 /* non-existent device */ 131 #else 132 #define NODEV (dev_t)(-1) /* non-existent device */ 133 #endif 134 135 /* 136 * Clustering of hardware pages on machines with ridiculously small 137 * page sizes is done here. The paging subsystem deals with units of 138 * CLSIZE pte's describing PAGE_SIZE (from machine/machparam.h) pages each. 139 */ 140 #if 0 141 #define CLBYTES (CLSIZE*PAGE_SIZE) 142 #endif 143 144 #define CBLOCK 128 /* Clist block size, must be a power of 2. */ 145 #define CBQSIZE (CBLOCK/NBBY) /* Quote bytes/cblock - can do better. */ 146 /* Data chars/clist. */ 147 #define CBSIZE (CBLOCK - sizeof(struct cblock *) - CBQSIZE) 148 #define CROUND (CBLOCK - 1) /* Clist rounding. */ 149 150 /* 151 * File system parameters and macros. 152 * 153 * MAXBSIZE - Filesystems are made out of blocks of at most MAXBSIZE bytes 154 * per block. MAXBSIZE may be made larger without effecting 155 * any existing filesystems as long as it does not exceed MAXPHYS, 156 * and may be made smaller at the risk of not being able to use 157 * filesystems which require a block size exceeding MAXBSIZE. 158 * 159 * BKVASIZE - Nominal buffer space per buffer, in bytes. BKVASIZE is the 160 * minimum KVM memory reservation the kernel is willing to make. 161 * Filesystems can of course request smaller chunks. Actual 162 * backing memory uses a chunk size of a page (PAGE_SIZE). 163 * 164 * If you make BKVASIZE too small you risk seriously fragmenting 165 * the buffer KVM map which may slow things down a bit. If you 166 * make it too big the kernel will not be able to optimally use 167 * the KVM memory reserved for the buffer cache and will wind 168 * up with too-few buffers. 169 * 170 * The default is 16384, roughly 2x the block size used by a 171 * normal UFS filesystem. 172 */ 173 #define MAXBSIZE 65536 /* must be power of 2 */ 174 #define BKVASIZE 16384 /* must be power of 2 */ 175 #define BKVAMASK (BKVASIZE-1) 176 #define MAXFRAG 8 177 178 /* 179 * MAXPATHLEN defines the longest permissible path length after expanding 180 * symbolic links. It is used to allocate a temporary buffer from the buffer 181 * pool in which to do the name expansion, hence should be a power of two, 182 * and must be less than or equal to MAXBSIZE. MAXSYMLINKS defines the 183 * maximum number of symbolic links that may be expanded in a path name. 184 * It should be set high enough to allow all legitimate uses, but halt 185 * infinite loops reasonably quickly. 186 */ 187 #define MAXPATHLEN PATH_MAX 188 #define MAXSYMLINKS 32 189 190 /* Bit map related macros. */ 191 #define setbit(a,i) ((a)[(i)/NBBY] |= 1<<((i)%NBBY)) 192 #define clrbit(a,i) ((a)[(i)/NBBY] &= ~(1<<((i)%NBBY))) 193 #define isset(a,i) ((a)[(i)/NBBY] & (1<<((i)%NBBY))) 194 #define isclr(a,i) (((a)[(i)/NBBY] & (1<<((i)%NBBY))) == 0) 195 196 /* Macros for counting and rounding. */ 197 #ifndef howmany 198 #define howmany(x, y) (((x)+((y)-1))/(y)) 199 #endif 200 #define rounddown(x, y) (((x)/(y))*(y)) 201 #define roundup(x, y) ((((x)+((y)-1))/(y))*(y)) /* to any y */ 202 #define roundup2(x, y) (((x)+((y)-1))&(~((y)-1))) /* if y is powers of two */ 203 #define powerof2(x) ((((x)-1)&(x))==0) 204 205 /* Macros for min/max. */ 206 #define MIN(a,b) (((a)<(b))?(a):(b)) 207 #define MAX(a,b) (((a)>(b))?(a):(b)) 208 209 /* 210 * Constants for setting the parameters of the kernel memory allocator. 211 * 212 * 2 ** MINBUCKET is the smallest unit of memory that will be 213 * allocated. It must be at least large enough to hold a pointer. 214 * 215 * Units of memory less or equal to MAXALLOCSAVE will permanently 216 * allocate physical memory; requests for these size pieces of 217 * memory are quite fast. Allocations greater than MAXALLOCSAVE must 218 * always allocate and free physical memory; requests for these 219 * size allocations should be done infrequently as they will be slow. 220 * 221 * Constraints: PAGE_SIZE <= MAXALLOCSAVE <= 2 ** (MINBUCKET + 14), and 222 * MAXALLOCSIZE must be a power of two. 223 */ 224 #if defined(__alpha__) 225 #define MINBUCKET 5 /* 5 => min allocation of 32 bytes */ 226 #else 227 #define MINBUCKET 4 /* 4 => min allocation of 16 bytes */ 228 #endif 229 #define MAXALLOCSAVE (2 * PAGE_SIZE) 230 231 /* 232 * Scale factor for scaled integers used to count %cpu time and load avgs. 233 * 234 * The number of CPU `tick's that map to a unique `%age' can be expressed 235 * by the formula (1 / (2 ^ (FSHIFT - 11))). The maximum load average that 236 * can be calculated (assuming 32 bits) can be closely approximated using 237 * the formula (2 ^ (2 * (16 - FSHIFT))) for (FSHIFT < 15). 238 * 239 * For the scheduler to maintain a 1:1 mapping of CPU `tick' to `%age', 240 * FSHIFT must be at least 11; this gives us a maximum load avg of ~1024. 241 */ 242 #define FSHIFT 11 /* bits to right of fixed binary point */ 243 #define FSCALE (1<<FSHIFT) 244 245 #define dbtoc(db) /* calculates devblks to pages */ \ 246 ((db + (ctodb(1) - 1)) >> (PAGE_SHIFT - DEV_BSHIFT)) 247 248 #define ctodb(db) /* calculates pages to devblks */ \ 249 ((db) << (PAGE_SHIFT - DEV_BSHIFT)) 250 251 252 /* 253 * Make this available for most of the kernel. There were too many 254 * things that included sys/systm.h just for panic(). 255 */ 256 #ifdef _KERNEL 257 void panic (const char *, ...) __dead2 __printflike(1, 2); 258 #endif 259 260 #endif /* _SYS_PARAM_H_ */ 261