xref: /dragonfly/sys/sys/param.h (revision 1f8a7fec)
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 1.53 2008/11/11 00:55:49 pavalos Exp $
41  */
42 
43 #ifndef _SYS_PARAM_H_
44 #define _SYS_PARAM_H_
45 
46 #define BSD	200708		/* XXX kern.osrevision */
47 #define BSD4_3	1		/* XXX obsolete */
48 #define BSD4_4	1		/* XXX obsolete */
49 
50 /*
51  * __DragonFly_version number.  The number doesn't really meaningfully
52  * translate to a version number.
53  *
54  * 170000 - base development version after 1.6 branch
55  * 170001 - base development version before 1.8 branch
56  * 190000 - base development version after 1.8 branch
57  * 195000 - base development version after 1.10 branch
58  * 197500 - base development version before 1.12 branch
59  * 197600 - 1.12 branch
60  * 197700 - base development version after 1.12 branch
61  * 199900 - base development version before 2.0 branch
62  * 200000 - 2.0 branch
63  * 200100 - base development version after 2.0 branch
64  * 200101 - lchflags syscall
65  * 200200 - 2.2 branch
66  * 200201 - base development version after 2.2 branch
67  * 200202 - major changes to libc
68  * 200203 - introduce PCI domain
69  * 200204 - suser() & suser_cred() removal
70  * 200205 - devfs import
71  * 200206 - *sleep() renames
72  * 200400 - 2.4 branch
73  * 200500 - 2.5 master
74  * 200600 - 2.6 branch
75  * 200700 - 2.7 master
76  */
77 #undef __DragonFly_version
78 #define __DragonFly_version 200700	/* propagated to newvers */
79 
80 #include <sys/_null.h>
81 
82 #ifndef LOCORE
83 #include <sys/types.h>
84 #endif
85 
86 /*
87  * Machine-independent constants (some used in following include files).
88  * Redefined constants are from POSIX 1003.1 limits file.
89  *
90  * MAXCOMLEN should be >= sizeof(ac_comm) (see <acct.h>)
91  * MAXLOGNAME should be == UT_NAMESIZE+1 (see <utmp.h>)
92  */
93 #include <sys/syslimits.h>
94 
95 #define MAXCOMLEN	16		/* max command name remembered */
96 #define MAXINTERP	32		/* max interpreter file name length */
97 #define MAXLOGNAME	17		/* max login name length (incl. NUL) */
98 #define MAXUPRC		CHILD_MAX	/* max simultaneous processes */
99 #define NCARGS		ARG_MAX		/* max bytes for an exec function */
100 #define NGROUPS		NGROUPS_MAX	/* max number groups */
101 #define NOFILE		OPEN_MAX	/* max open files per process */
102 #define NOGROUP		65535		/* marker for empty group set member */
103 #define MAXHOSTNAMELEN	256		/* max hostname size */
104 
105 /* More types and definitions used throughout the kernel. */
106 #ifdef _KERNEL
107 #include <sys/cdefs.h>
108 #include <sys/errno.h>
109 #include <sys/time.h>
110 
111 #define FALSE	0
112 #define TRUE	1
113 #endif
114 
115 #ifndef _KERNEL
116 /* Signals. */
117 #include <sys/select.h>
118 #include <sys/signal.h>
119 #endif
120 
121 /* Machine type dependent parameters. */
122 #include <machine/param.h>
123 #ifndef _KERNEL
124 #include <machine/limits.h>
125 #endif
126 
127 #define PCATCH		0x00000100	/* tsleep checks signals */
128 #define PUSRFLAG1	0x00000200	/* Subsystem specific flag */
129 #define PINTERLOCKED	0x00000400	/* Interlocked tsleep */
130 #define PWAKEUP_CPUMASK	0x00003FFF	/* start cpu for chained wakeups */
131 #define PWAKEUP_MYCPU	0x00004000	/* wakeup on current cpu only */
132 #define PWAKEUP_ONE	0x00008000	/* argument to wakeup: only one */
133 #define PDOMAIN_MASK	0xFFFF0000	/* address domains for wakeup */
134 #define PDOMAIN_UMTX	0x00010000	/* independant domain for UMTX */
135 #define PWAKEUP_ENCODE(domain, cpu)	((domain) | (cpu))
136 #define PWAKEUP_DECODE(domain)		((domain) & PWAKEUP_CPUMASK)
137 
138 #define NZERO	0		/* default "nice" */
139 
140 #define NBPW	sizeof(int)	/* number of bytes per word (integer) */
141 
142 #define CMASK	022		/* default file mask: S_IWGRP|S_IWOTH */
143 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
144 #define NOUDEV	(udev_t)(-1)	/* non-existent device */
145 #define NOMAJ	256		/* non-existent device */
146 #endif
147 
148 #ifndef _KERNEL
149 #define NODEV	(dev_t)(-1)	/* non-existent device */
150 #endif
151 
152 /*
153  * File system parameters and macros.
154  *
155  * MAXBSIZE -	Filesystems are made out of blocks of at most MAXBSIZE bytes
156  *		per block.  MAXBSIZE may be made larger without effecting
157  *		any existing filesystems as long as it does not exceed MAXPHYS,
158  *		and may be made smaller at the risk of not being able to use
159  *		filesystems which require a block size exceeding MAXBSIZE.
160  *
161  * BKVASIZE -	Nominal buffer space per buffer, in bytes.  BKVASIZE is the
162  *		minimum KVM memory reservation the kernel is willing to make.
163  *		Filesystems can of course request smaller chunks.  Actual
164  *		backing memory uses a chunk size of a page (PAGE_SIZE).
165  *
166  *		If you make BKVASIZE too small you risk seriously fragmenting
167  *		the buffer KVM map which may slow things down a bit.  If you
168  *		make it too big the kernel will not be able to optimally use
169  *		the KVM memory reserved for the buffer cache and will wind
170  *		up with too-few buffers.
171  *
172  *		The default is 16384, roughly 2x the block size used by a
173  *		normal UFS filesystem.
174  */
175 #define MAXBSIZE	65536	/* must be power of 2 */
176 #define BKVASIZE	16384	/* must be power of 2 */
177 #define BKVAMASK	(BKVASIZE-1)
178 #define MAXFRAG 	8
179 
180 /*
181  * MAXPATHLEN defines the longest permissible path length after expanding
182  * symbolic links. It is used to allocate a temporary buffer from the buffer
183  * pool in which to do the name expansion, hence should be a power of two,
184  * and must be less than or equal to MAXBSIZE.  MAXSYMLINKS defines the
185  * maximum number of symbolic links that may be expanded in a path name.
186  * It should be set high enough to allow all legitimate uses, but halt
187  * infinite loops reasonably quickly.
188  */
189 #define MAXPATHLEN	PATH_MAX
190 #define MAXSYMLINKS	32
191 
192 /* Bit map related macros. */
193 #define setbit(a,i)	((a)[(i)/NBBY] |= 1<<((i)%NBBY))
194 #define clrbit(a,i)	((a)[(i)/NBBY] &= ~(1<<((i)%NBBY)))
195 #define isset(a,i)	((a)[(i)/NBBY] & (1<<((i)%NBBY)))
196 #define isclr(a,i)	(((a)[(i)/NBBY] & (1<<((i)%NBBY))) == 0)
197 
198 /* Macros for counting and rounding. */
199 #ifndef howmany
200 #define howmany(x, y)	(((x)+((y)-1))/(y))
201 #endif
202 #define rounddown(x, y)	(((x)/(y))*(y))
203 #define roundup(x, y)	((((x)+((y)-1))/(y))*(y))  /* to any y */
204 #define roundup2(x, y)	(((x)+((y)-1))&(~((y)-1))) /* if y is powers of two */
205 #define powerof2(x)	((((x)-1)&(x))==0)
206 
207 /*
208  * VM objects can be larger than the virtual address space, make sure
209  * we don't cut-off the mask.
210  */
211 #define trunc_page64(x)           ((x) & ~(int64_t)PAGE_MASK)
212 #define round_page64(x)           (((x) + PAGE_MASK) & ~(int64_t)PAGE_MASK)
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 #define MINBUCKET	4		/* 4 => min allocation of 16 bytes */
234 #define MAXALLOCSAVE	(2 * PAGE_SIZE)
235 
236 /*
237  * Scale factor for scaled integers used to count %cpu time and load avgs.
238  *
239  * The number of CPU `tick's that map to a unique `%age' can be expressed
240  * by the formula (1 / (2 ^ (FSHIFT - 11))).  The maximum load average that
241  * can be calculated (assuming 32 bits) can be closely approximated using
242  * the formula (2 ^ (2 * (16 - FSHIFT))) for (FSHIFT < 15).
243  *
244  * For the scheduler to maintain a 1:1 mapping of CPU `tick' to `%age',
245  * FSHIFT must be at least 11; this gives us a maximum load avg of ~1024.
246  */
247 #define FSHIFT	11		/* bits to right of fixed binary point */
248 #define FSCALE	(1<<FSHIFT)
249 
250 #define dbtoc(db)			/* calculates devblks to pages */ \
251 	((db + (ctodb(1) - 1)) >> (PAGE_SHIFT - DEV_BSHIFT))
252 
253 #define ctodb(db)			/* calculates pages to devblks */ \
254 	((db) << (PAGE_SHIFT - DEV_BSHIFT))
255 
256 #define MJUMPAGESIZE	PAGE_SIZE	/* jumbo cluster 4k */
257 #define MJUM9BYTES	(9 * 1024)	/* jumbo cluster 9k */
258 #define MJUM16BYTES	(16 * 1024)	/* jumbo cluster 16k */
259 
260 /*
261  * MBUF Management.
262  *
263  * Because many drivers can't deal with multiple DMA segments all mbufs
264  * must avoid crossing a page boundary.  While we can accomodate mbufs
265  * which are not a power-of-2 sized kmalloc() will only guarantee
266  * non-crossing alignment if we use a power-of-2.  256 is no longer large
267  * enough due to m_hdr and m_pkthdr bloat.
268  *
269  * MCLBYTES must be a power of 2 and is typically significantly larger
270  * than MSIZE, sufficient to hold a standard-mtu packet.  2K is considered
271  * reasonable.
272  */
273 #ifndef MSIZE
274 #define MSIZE		512		/* size of an mbuf */
275 #endif
276 
277 #ifndef MCLSHIFT
278 #define MCLSHIFT        11              /* convert bytes to m_buf clusters */
279 #endif
280 #define MCLBYTES        (1 << MCLSHIFT) /* size of an m_buf cluster */
281 #define MCLOFSET        (MCLBYTES - 1)  /* offset within an m_buf cluster */
282 
283 /*
284  * Make this available for most of the kernel.  There were too many
285  * things that included sys/systm.h just for panic().
286  */
287 #ifdef _KERNEL
288 void	panic (const char *, ...) __dead2 __printflike(1, 2);
289 #endif
290 
291 #ifndef htonl
292 #define	htonl(x)	__htonl(x)
293 #endif
294 #ifndef htons
295 #define	htons(x)	__htons(x)
296 #endif
297 #ifndef ntohl
298 #define	ntohl(x)	__ntohl(x)
299 #endif
300 #ifndef ntohs
301 #define	ntohs(x)	__ntohs(x)
302 #endif
303 
304 #endif	/* _SYS_PARAM_H_ */
305