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 1.11 2004/01/05 17:36:20 drhodus Exp $ 41 */ 42 43 #ifndef _SYS_PARAM_H_ 44 #define _SYS_PARAM_H_ 45 46 #define BSD 200307 /* XXX kern.osrevision */ 47 #define BSD4_3 1 /* XXX obsolete */ 48 #define BSD4_4 1 /* XXX obsolete */ 49 50 /* 51 * __DragonFly_version number. Note that the name and comment are pattern 52 * searched from conf/newvers.sh. 53 * 54 * Version changes should be documented in: 55 * doc/en_US.ISO8859-1/books/porters-handbook/book.sgml 56 */ 57 #undef __DragonFly_version 58 #define __DragonFly_version 100000 /* Master, propagated to newvers */ 59 60 /* 61 * __FreeBSD_version numbers for source compatibility. This is temporary 62 * along with the __FreeBSD__ define in gcc. 63 */ 64 #undef __FreeBSD_version 65 #define __FreeBSD_version 480101 66 67 #ifndef NULL 68 #define NULL 0 69 #endif 70 71 #ifndef LOCORE 72 #include <sys/types.h> 73 #endif 74 75 /* 76 * Machine-independent constants (some used in following include files). 77 * Redefined constants are from POSIX 1003.1 limits file. 78 * 79 * MAXCOMLEN should be >= sizeof(ac_comm) (see <acct.h>) 80 * MAXLOGNAME should be == UT_NAMESIZE+1 (see <utmp.h>) 81 */ 82 #include <sys/syslimits.h> 83 84 #define MAXCOMLEN 16 /* max command name remembered */ 85 #define MAXINTERP 32 /* max interpreter file name length */ 86 #define MAXLOGNAME 17 /* max login name length (incl. NUL) */ 87 #define MAXUPRC CHILD_MAX /* max simultaneous processes */ 88 #define NCARGS ARG_MAX /* max bytes for an exec function */ 89 #define NGROUPS NGROUPS_MAX /* max number groups */ 90 #define NOFILE OPEN_MAX /* max open files per process */ 91 #define NOGROUP 65535 /* marker for empty group set member */ 92 #define MAXHOSTNAMELEN 256 /* max hostname size */ 93 94 /* More types and definitions used throughout the kernel. */ 95 #ifdef _KERNEL 96 #include <sys/cdefs.h> 97 #include <sys/errno.h> 98 #include <sys/time.h> 99 100 #define FALSE 0 101 #define TRUE 1 102 #endif 103 104 #ifndef _KERNEL 105 /* Signals. */ 106 #include <sys/signal.h> 107 #endif 108 109 /* Machine type dependent parameters. */ 110 #include <machine/param.h> 111 #ifndef _KERNEL 112 #include <machine/limits.h> 113 #endif 114 115 /* 116 * Priorities. Note that with 32 run queues, differences less than 4 are 117 * insignificant. 118 */ 119 #define MAXPRI 127 /* Priorities range from 0 through MAXPRI. */ 120 #define PPAUSE 40 121 #define PRIMASK 127 122 #define PRIBASE_REALTIME 0 123 #define PRIBASE_NORMAL 128 124 #define PRIBASE_IDLE 256 125 #define PRIBASE_THREAD 384 /* huh? */ 126 #define PRIBIO 16 127 128 #define PCATCH 0x0100 /* OR'd with pri for tsleep to check signals */ 129 #define PUSRFLAG1 0x0200 /* Subsystem specific flag */ 130 131 #define NZERO 0 /* default "nice" */ 132 133 #define NBPW sizeof(int) /* number of bytes per word (integer) */ 134 135 #define CMASK 022 /* default file mask: S_IWGRP|S_IWOTH */ 136 #ifdef _KERNEL 137 #define NODEV (dev_t)(-1) /* non-existent device */ 138 #define NOUDEV (udev_t)(-1) /* non-existent device */ 139 #define NOMAJ 256 /* non-existent device */ 140 #else 141 #define NODEV (dev_t)(-1) /* non-existent device */ 142 #endif 143 144 /* 145 * Clustering of hardware pages on machines with ridiculously small 146 * page sizes is done here. The paging subsystem deals with units of 147 * CLSIZE pte's describing PAGE_SIZE (from machine/machparam.h) pages each. 148 */ 149 #if 0 150 #define CLBYTES (CLSIZE*PAGE_SIZE) 151 #endif 152 153 #define CBLOCK 128 /* Clist block size, must be a power of 2. */ 154 #define CBQSIZE (CBLOCK/NBBY) /* Quote bytes/cblock - can do better. */ 155 /* Data chars/clist. */ 156 #define CBSIZE (CBLOCK - sizeof(struct cblock *) - CBQSIZE) 157 #define CROUND (CBLOCK - 1) /* Clist rounding. */ 158 159 /* 160 * File system parameters and macros. 161 * 162 * MAXBSIZE - Filesystems are made out of blocks of at most MAXBSIZE bytes 163 * per block. MAXBSIZE may be made larger without effecting 164 * any existing filesystems as long as it does not exceed MAXPHYS, 165 * and may be made smaller at the risk of not being able to use 166 * filesystems which require a block size exceeding MAXBSIZE. 167 * 168 * BKVASIZE - Nominal buffer space per buffer, in bytes. BKVASIZE is the 169 * minimum KVM memory reservation the kernel is willing to make. 170 * Filesystems can of course request smaller chunks. Actual 171 * backing memory uses a chunk size of a page (PAGE_SIZE). 172 * 173 * If you make BKVASIZE too small you risk seriously fragmenting 174 * the buffer KVM map which may slow things down a bit. If you 175 * make it too big the kernel will not be able to optimally use 176 * the KVM memory reserved for the buffer cache and will wind 177 * up with too-few buffers. 178 * 179 * The default is 16384, roughly 2x the block size used by a 180 * normal UFS filesystem. 181 */ 182 #define MAXBSIZE 65536 /* must be power of 2 */ 183 #define BKVASIZE 16384 /* must be power of 2 */ 184 #define BKVAMASK (BKVASIZE-1) 185 #define MAXFRAG 8 186 187 /* 188 * MAXPATHLEN defines the longest permissible path length after expanding 189 * symbolic links. It is used to allocate a temporary buffer from the buffer 190 * pool in which to do the name expansion, hence should be a power of two, 191 * and must be less than or equal to MAXBSIZE. MAXSYMLINKS defines the 192 * maximum number of symbolic links that may be expanded in a path name. 193 * It should be set high enough to allow all legitimate uses, but halt 194 * infinite loops reasonably quickly. 195 */ 196 #define MAXPATHLEN PATH_MAX 197 #define MAXSYMLINKS 32 198 199 /* Bit map related macros. */ 200 #define setbit(a,i) ((a)[(i)/NBBY] |= 1<<((i)%NBBY)) 201 #define clrbit(a,i) ((a)[(i)/NBBY] &= ~(1<<((i)%NBBY))) 202 #define isset(a,i) ((a)[(i)/NBBY] & (1<<((i)%NBBY))) 203 #define isclr(a,i) (((a)[(i)/NBBY] & (1<<((i)%NBBY))) == 0) 204 205 /* Macros for counting and rounding. */ 206 #ifndef howmany 207 #define howmany(x, y) (((x)+((y)-1))/(y)) 208 #endif 209 #define rounddown(x, y) (((x)/(y))*(y)) 210 #define roundup(x, y) ((((x)+((y)-1))/(y))*(y)) /* to any y */ 211 #define roundup2(x, y) (((x)+((y)-1))&(~((y)-1))) /* if y is powers of two */ 212 #define powerof2(x) ((((x)-1)&(x))==0) 213 214 /* Macros for min/max. */ 215 #define MIN(a,b) (((a)<(b))?(a):(b)) 216 #define MAX(a,b) (((a)>(b))?(a):(b)) 217 218 /* 219 * Constants for setting the parameters of the kernel memory allocator. 220 * 221 * 2 ** MINBUCKET is the smallest unit of memory that will be 222 * allocated. It must be at least large enough to hold a pointer. 223 * 224 * Units of memory less or equal to MAXALLOCSAVE will permanently 225 * allocate physical memory; requests for these size pieces of 226 * memory are quite fast. Allocations greater than MAXALLOCSAVE must 227 * always allocate and free physical memory; requests for these 228 * size allocations should be done infrequently as they will be slow. 229 * 230 * Constraints: PAGE_SIZE <= MAXALLOCSAVE <= 2 ** (MINBUCKET + 14), and 231 * MAXALLOCSIZE must be a power of two. 232 */ 233 #if defined(__alpha__) 234 #define MINBUCKET 5 /* 5 => min allocation of 32 bytes */ 235 #else 236 #define MINBUCKET 4 /* 4 => min allocation of 16 bytes */ 237 #endif 238 #define MAXALLOCSAVE (2 * PAGE_SIZE) 239 240 /* 241 * Scale factor for scaled integers used to count %cpu time and load avgs. 242 * 243 * The number of CPU `tick's that map to a unique `%age' can be expressed 244 * by the formula (1 / (2 ^ (FSHIFT - 11))). The maximum load average that 245 * can be calculated (assuming 32 bits) can be closely approximated using 246 * the formula (2 ^ (2 * (16 - FSHIFT))) for (FSHIFT < 15). 247 * 248 * For the scheduler to maintain a 1:1 mapping of CPU `tick' to `%age', 249 * FSHIFT must be at least 11; this gives us a maximum load avg of ~1024. 250 */ 251 #define FSHIFT 11 /* bits to right of fixed binary point */ 252 #define FSCALE (1<<FSHIFT) 253 254 #define dbtoc(db) /* calculates devblks to pages */ \ 255 ((db + (ctodb(1) - 1)) >> (PAGE_SHIFT - DEV_BSHIFT)) 256 257 #define ctodb(db) /* calculates pages to devblks */ \ 258 ((db) << (PAGE_SHIFT - DEV_BSHIFT)) 259 260 261 /* 262 * Make this available for most of the kernel. There were too many 263 * things that included sys/systm.h just for panic(). 264 */ 265 #ifdef _KERNEL 266 void panic (const char *, ...) __dead2 __printflike(1, 2); 267 #endif 268 269 #endif /* _SYS_PARAM_H_ */ 270