xref: /dragonfly/sys/sys/param.h (revision a32bc35d)
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  */
41 
42 #ifndef _SYS_PARAM_H_
43 #define _SYS_PARAM_H_
44 
45 #define BSD	200708		/* XXX kern.osrevision */
46 #define BSD4_3	1		/* XXX obsolete */
47 #define BSD4_4	1		/* XXX obsolete */
48 
49 /*
50  * __DragonFly_version number.  The number doesn't really meaningfully
51  * translate to a version number.
52  *
53  * 170000 - base development version after 1.6 branch
54  * 170001 - base development version before 1.8 branch
55  * 190000 - base development version after 1.8 branch
56  * 195000 - base development version after 1.10 branch
57  * 197500 - base development version before 1.12 branch
58  * 197600 - 1.12 branch
59  * 197700 - base development version after 1.12 branch
60  * 199900 - base development version before 2.0 branch
61  * 200000 - 2.0 branch
62  * 200100 - base development version after 2.0 branch
63  * 200101 - lchflags syscall
64  * 200200 - 2.2 branch
65  * 200201 - base development version after 2.2 branch
66  * 200202 - major changes to libc
67  * 200203 - introduce PCI domain
68  * 200204 - suser() & suser_cred() removal
69  * 200205 - devfs import
70  * 200206 - *sleep() renames
71  * 200400 - 2.4 release
72  * 200500 - 2.5 master
73  * 200600 - 2.6 release
74  * 200700 - 2.7 master
75  * 200800 - 2.8 release			October 2010
76  * 200900 - 2.9 master
77  * 200901 - prototype changes for alphasort(3) and scandir(3)
78  * 200902 - Xerox NS protocol removal
79  * 201000 - 2.10 release
80  * 201100 - 2.11 master
81  * 201200 - 2.12 release
82  * 201300 - 2.13 master
83  * 201301 - header rename: <vfs/gnu/ext2fs/...> -> <gnu/vfs/ext2fs/...>
84  * 201302 - header <crypt.h> is gone
85  * 201303 - <netatalk/...> and <netproto/atalk/...> are gone
86  * 201304 - Added wcscasecmp, wcsncasecmp to libc
87  * 201305 - Sync libm with NetBSD-current libm (new functions added)
88  * 201306 - Sync libm with FreeBSD-current libm (~50 new functions)
89  * 300000 - 3.0 release
90  * 300100 - 3.1 master
91  * 300101 - i4b (ISDN) removal
92  * 300102 - <sys/ata.h> is now just a link of <sys/nata.h>
93  * 300103 - if SIG_IGN is set on SIGCHLD, do not keep zombie children
94  */
95 #undef __DragonFly_version
96 #define __DragonFly_version 300103	/* propagated to newvers */
97 
98 #include <sys/_null.h>
99 
100 #ifndef LOCORE
101 #include <sys/types.h>
102 #endif
103 
104 /*
105  * Machine-independent constants (some used in following include files).
106  * Redefined constants are from POSIX 1003.1 limits file.
107  *
108  * MAXCOMLEN should be >= sizeof(ac_comm) (see <acct.h>)
109  * MAXLOGNAME should be == UT_NAMESIZE+1 (see <utmp.h>)
110  */
111 #include <sys/syslimits.h>
112 
113 #define MAXCOMLEN	16		/* max command name remembered */
114 #define MAXINTERP	32		/* max interpreter file name length */
115 #define MAXLOGNAME	17		/* max login name length (incl. NUL) */
116 #define MAXUPRC		CHILD_MAX	/* max simultaneous processes */
117 #define NCARGS		ARG_MAX		/* max bytes for an exec function */
118 #define NGROUPS		NGROUPS_MAX	/* max number groups */
119 #define NOFILE		OPEN_MAX	/* max open files per process */
120 #define NOGROUP		65535		/* marker for empty group set member */
121 #define MAXHOSTNAMELEN	256		/* max hostname size */
122 
123 /* More types and definitions used throughout the kernel. */
124 #ifdef _KERNEL
125 #include <sys/cdefs.h>
126 #include <sys/errno.h>
127 #include <sys/time.h>
128 
129 #define FALSE	0
130 #define TRUE	1
131 #endif
132 
133 #ifndef _KERNEL
134 /* Signals. */
135 #include <sys/select.h>
136 #include <sys/signal.h>
137 #endif
138 
139 /* Machine type dependent parameters. */
140 #include <machine/param.h>
141 #ifndef _KERNEL
142 #include <machine/limits.h>
143 #endif
144 
145 #define PCATCH		0x00000100	/* tsleep checks signals */
146 #define PUSRFLAG1	0x00000200	/* Subsystem specific flag */
147 #define PINTERLOCKED	0x00000400	/* Interlocked tsleep */
148 #define PWAKEUP_CPUMASK	0x00003FFF	/* start cpu for chained wakeups */
149 #define PWAKEUP_MYCPU	0x00004000	/* wakeup on current cpu only */
150 #define PWAKEUP_ONE	0x00008000	/* argument to wakeup: only one */
151 #define PDOMAIN_MASK	0xFFFF0000	/* address domains for wakeup */
152 #define PDOMAIN_UMTX	0x00010000	/* independant domain for UMTX */
153 #define PDOMAIN_XLOCK	0x00020000	/* independant domain for fifo_lock */
154 #define PWAKEUP_ENCODE(domain, cpu)	((domain) | (cpu))
155 #define PWAKEUP_DECODE(domain)		((domain) & PWAKEUP_CPUMASK)
156 
157 #define NZERO	0		/* default "nice" */
158 
159 #define NBPW	sizeof(int)	/* number of bytes per word (integer) */
160 
161 #define CMASK	022		/* default file mask: S_IWGRP|S_IWOTH */
162 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
163 #define NOUDEV	(udev_t)(-1)	/* non-existent device */
164 #define NOMAJ	256		/* non-existent device */
165 #endif
166 
167 #ifndef _KERNEL
168 #define NODEV	(dev_t)(-1)	/* non-existent device */
169 #endif
170 
171 /*
172  * cpu_mi_feature bits
173  */
174 #define CPU_MI_BZERONT	0x00000001
175 #define CPU_MI_MONITOR	0x00000010
176 
177 /*
178  * File system parameters and macros.
179  *
180  * MAXBSIZE -	Filesystems are made out of blocks of at most MAXBSIZE bytes
181  *		per block.  MAXBSIZE may be made larger without effecting
182  *		any existing filesystems as long as it does not exceed MAXPHYS,
183  *		and may be made smaller at the risk of not being able to use
184  *		filesystems which require a block size exceeding MAXBSIZE.
185  *
186  * BKVASIZE -	Nominal buffer space per buffer, in bytes.  BKVASIZE is the
187  *		minimum KVM memory reservation the kernel is willing to make.
188  *		Filesystems can of course request smaller chunks.  Actual
189  *		backing memory uses a chunk size of a page (PAGE_SIZE).
190  *
191  *		If you make BKVASIZE too small you risk seriously fragmenting
192  *		the buffer KVM map which may slow things down a bit.  If you
193  *		make it too big the kernel will not be able to optimally use
194  *		the KVM memory reserved for the buffer cache and will wind
195  *		up with too-few buffers.
196  *
197  *		The default is 16384, roughly 2x the block size used by a
198  *		normal UFS filesystem.
199  */
200 #define MAXBSIZE	65536	/* must be power of 2 */
201 #define BKVASIZE	16384	/* must be power of 2 */
202 #define BKVAMASK	(BKVASIZE-1)
203 #define MAXFRAG 	8
204 
205 /*
206  * MAXPATHLEN defines the longest permissible path length after expanding
207  * symbolic links. It is used to allocate a temporary buffer from the buffer
208  * pool in which to do the name expansion, hence should be a power of two,
209  * and must be less than or equal to MAXBSIZE.  MAXSYMLINKS defines the
210  * maximum number of symbolic links that may be expanded in a path name.
211  * It should be set high enough to allow all legitimate uses, but halt
212  * infinite loops reasonably quickly.
213  */
214 #define MAXPATHLEN	PATH_MAX
215 #define MAXSYMLINKS	32
216 
217 /* Bit map related macros. */
218 #define setbit(a,i)	((a)[(i)/NBBY] |= 1<<((i)%NBBY))
219 #define clrbit(a,i)	((a)[(i)/NBBY] &= ~(1<<((i)%NBBY)))
220 #define isset(a,i)	((a)[(i)/NBBY] & (1<<((i)%NBBY)))
221 #define isclr(a,i)	(((a)[(i)/NBBY] & (1<<((i)%NBBY))) == 0)
222 
223 /* Macros for counting and rounding. */
224 #ifndef howmany
225 #define howmany(x, y)	(((x)+((y)-1))/(y))
226 #endif
227 #define rounddown(x, y)	(((x)/(y))*(y))
228 #define rounddown2(x, y) ((x) & ~((y) - 1))	   /* y power of two */
229 #define roundup(x, y)	((((x)+((y)-1))/(y))*(y))  /* to any y */
230 #define roundup2(x, y)	(((x)+((y)-1))&(~((y)-1))) /* if y is powers of two */
231 #define powerof2(x)	((((x)-1)&(x))==0)
232 
233 /*
234  * VM objects can be larger than the virtual address space, make sure
235  * we don't cut-off the mask.
236  */
237 #define trunc_page64(x)           ((x) & ~(int64_t)PAGE_MASK)
238 #define round_page64(x)           (((x) + PAGE_MASK) & ~(int64_t)PAGE_MASK)
239 
240 /* Macros for min/max. */
241 #define MIN(a,b) (((a)<(b))?(a):(b))
242 #define MAX(a,b) (((a)>(b))?(a):(b))
243 
244 /* Macro for array size */
245 #define NELEM(ary) 	(sizeof(ary) / sizeof((ary)[0]))
246 
247 /*
248  * Constants for setting the parameters of the kernel memory allocator.
249  *
250  * 2 ** MINBUCKET is the smallest unit of memory that will be
251  * allocated. It must be at least large enough to hold a pointer.
252  *
253  * Units of memory less or equal to MAXALLOCSAVE will permanently
254  * allocate physical memory; requests for these size pieces of
255  * memory are quite fast. Allocations greater than MAXALLOCSAVE must
256  * always allocate and free physical memory; requests for these
257  * size allocations should be done infrequently as they will be slow.
258  *
259  * Constraints: PAGE_SIZE <= MAXALLOCSAVE <= 2 ** (MINBUCKET + 14), and
260  * MAXALLOCSIZE must be a power of two.
261  */
262 #define MINBUCKET	4		/* 4 => min allocation of 16 bytes */
263 #define MAXALLOCSAVE	(2 * PAGE_SIZE)
264 
265 /*
266  * Scale factor for scaled integers used to count %cpu time and load avgs.
267  *
268  * The number of CPU `tick's that map to a unique `%age' can be expressed
269  * by the formula (1 / (2 ^ (FSHIFT - 11))).  The maximum load average that
270  * can be calculated (assuming 32 bits) can be closely approximated using
271  * the formula (2 ^ (2 * (16 - FSHIFT))) for (FSHIFT < 15).
272  *
273  * For the scheduler to maintain a 1:1 mapping of CPU `tick' to `%age',
274  * FSHIFT must be at least 11; this gives us a maximum load avg of ~1024.
275  */
276 #define FSHIFT	11		/* bits to right of fixed binary point */
277 #define FSCALE	(1<<FSHIFT)
278 
279 #define dbtoc(db)			/* calculates devblks to pages */ \
280 	((db + (ctodb(1) - 1)) >> (PAGE_SHIFT - DEV_BSHIFT))
281 
282 #define ctodb(db)			/* calculates pages to devblks */ \
283 	((db) << (PAGE_SHIFT - DEV_BSHIFT))
284 
285 #define MJUMPAGESIZE	PAGE_SIZE	/* jumbo cluster 4k */
286 #define MJUM9BYTES	(9 * 1024)	/* jumbo cluster 9k */
287 #define MJUM16BYTES	(16 * 1024)	/* jumbo cluster 16k */
288 
289 /*
290  * MBUF Management.
291  *
292  * Because many drivers can't deal with multiple DMA segments all mbufs
293  * must avoid crossing a page boundary.  While we can accomodate mbufs
294  * which are not a power-of-2 sized kmalloc() will only guarantee
295  * non-crossing alignment if we use a power-of-2.  256 is no longer large
296  * enough due to m_hdr and m_pkthdr bloat.
297  *
298  * MCLBYTES must be a power of 2 and is typically significantly larger
299  * than MSIZE, sufficient to hold a standard-mtu packet.  2K is considered
300  * reasonable.
301  */
302 #ifndef MSIZE
303 #define MSIZE		512		/* size of an mbuf */
304 #endif
305 
306 #ifndef MCLSHIFT
307 #define MCLSHIFT        11              /* convert bytes to m_buf clusters */
308 #endif
309 #define MCLBYTES        (1 << MCLSHIFT) /* size of an m_buf cluster */
310 #define MCLOFSET        (MCLBYTES - 1)  /* offset within an m_buf cluster */
311 
312 /*
313  * Make this available for most of the kernel.  There were too many
314  * things that included sys/systm.h just for panic().
315  */
316 #ifdef _KERNEL
317 void	panic (const char *, ...) __dead2 __printflike(1, 2);
318 #endif
319 
320 #ifndef htonl
321 #define	htonl(x)	__htonl(x)
322 #endif
323 #ifndef htons
324 #define	htons(x)	__htons(x)
325 #endif
326 #ifndef ntohl
327 #define	ntohl(x)	__ntohl(x)
328 #endif
329 #ifndef ntohs
330 #define	ntohs(x)	__ntohs(x)
331 #endif
332 
333 #endif	/* _SYS_PARAM_H_ */
334