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 * 4. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 *	@(#)param.h	8.3 (Berkeley) 4/4/95
35 * $FreeBSD$
36 */
37
38#ifndef _SYS_PARAM_H_
39#define _SYS_PARAM_H_
40
41#include <sys/_null.h>
42
43#define	BSD	199506		/* System version (year & month). */
44#define BSD4_3	1
45#define BSD4_4	1
46
47/*
48 * __FreeBSD_version numbers are documented in the Porter's Handbook.
49 * If you bump the version for any reason, you should update the documentation
50 * there.
51 * Currently this lives here in the doc/ repository:
52 *
53 *	head/en_US.ISO8859-1/books/porters-handbook/versions/chapter.xml
54 *
55 * scheme is:  <major><two digit minor>Rxx
56 *		'R' is in the range 0 to 4 if this is a release branch or
57 *		x.0-CURRENT before RELENG_*_0 is created, otherwise 'R' is
58 *		in the range 5 to 9.
59 */
60#undef __FreeBSD_version
61#define __FreeBSD_version 1100100	/* Master, propagated to newvers */
62
63/*
64 * __FreeBSD_kernel__ indicates that this system uses the kernel of FreeBSD,
65 * which by definition is always true on FreeBSD. This macro is also defined
66 * on other systems that use the kernel of FreeBSD, such as GNU/kFreeBSD.
67 *
68 * It is tempting to use this macro in userland code when we want to enable
69 * kernel-specific routines, and in fact it's fine to do this in code that
70 * is part of FreeBSD itself.  However, be aware that as presence of this
71 * macro is still not widespread (e.g. older FreeBSD versions, 3rd party
72 * compilers, etc), it is STRONGLY DISCOURAGED to check for this macro in
73 * external applications without also checking for __FreeBSD__ as an
74 * alternative.
75 */
76#undef __FreeBSD_kernel__
77#define __FreeBSD_kernel__
78
79#ifdef _KERNEL
80#define	P_OSREL_SIGWAIT			700000
81#define	P_OSREL_SIGSEGV			700004
82#define	P_OSREL_MAP_ANON		800104
83#define	P_OSREL_MAP_FSTRICT		1100036
84#define	P_OSREL_SHUTDOWN_ENOTCONN	1100077
85
86#define	P_OSREL_MAJOR(x)		((x) / 100000)
87#endif
88
89#ifndef LOCORE
90#include <sys/types.h>
91#endif
92
93/*
94 * Machine-independent constants (some used in following include files).
95 * Redefined constants are from POSIX 1003.1 limits file.
96 *
97 * MAXCOMLEN should be >= sizeof(ac_comm) (see <acct.h>)
98 */
99#include <sys/syslimits.h>
100
101#define	MAXCOMLEN	19		/* max command name remembered */
102#define	MAXINTERP	PATH_MAX	/* max interpreter file name length */
103#define	MAXLOGNAME	33		/* max login name length (incl. NUL) */
104#define	MAXUPRC		CHILD_MAX	/* max simultaneous processes */
105#define	NCARGS		ARG_MAX		/* max bytes for an exec function */
106#define	NGROUPS		(NGROUPS_MAX+1)	/* max number groups */
107#define	NOFILE		OPEN_MAX	/* max open files per process */
108#define	NOGROUP		65535		/* marker for empty group set member */
109#define MAXHOSTNAMELEN	256		/* max hostname size */
110#define SPECNAMELEN	63		/* max length of devicename */
111
112/* More types and definitions used throughout the kernel. */
113#ifdef _KERNEL
114#include <sys/cdefs.h>
115#include <sys/errno.h>
116#ifndef LOCORE
117#include <sys/time.h>
118#include <sys/priority.h>
119#endif
120
121#ifndef FALSE
122#define	FALSE	0
123#endif
124#ifndef TRUE
125#define	TRUE	1
126#endif
127#endif
128
129#ifndef _KERNEL
130/* Signals. */
131#include <sys/signal.h>
132#endif
133
134/* Machine type dependent parameters. */
135#include <machine/param.h>
136#ifndef _KERNEL
137#include <sys/limits.h>
138#endif
139
140#ifndef DEV_BSHIFT
141#define	DEV_BSHIFT	9		/* log2(DEV_BSIZE) */
142#endif
143#define	DEV_BSIZE	(1<<DEV_BSHIFT)
144
145#ifndef BLKDEV_IOSIZE
146#define BLKDEV_IOSIZE  PAGE_SIZE	/* default block device I/O size */
147#endif
148#ifndef DFLTPHYS
149#define DFLTPHYS	(64 * 1024)	/* default max raw I/O transfer size */
150#endif
151#ifndef MAXPHYS
152#define MAXPHYS		(128 * 1024)	/* max raw I/O transfer size */
153#endif
154#ifndef MAXDUMPPGS
155#define MAXDUMPPGS	(DFLTPHYS/PAGE_SIZE)
156#endif
157
158/*
159 * Constants related to network buffer management.
160 * MCLBYTES must be no larger than PAGE_SIZE.
161 */
162#ifndef	MSIZE
163#define	MSIZE		256		/* size of an mbuf */
164#endif
165
166#ifndef	MCLSHIFT
167#define MCLSHIFT	11		/* convert bytes to mbuf clusters */
168#endif	/* MCLSHIFT */
169
170#define MCLBYTES	(1 << MCLSHIFT)	/* size of an mbuf cluster */
171
172#if PAGE_SIZE < 2048
173#define	MJUMPAGESIZE	MCLBYTES
174#elif PAGE_SIZE <= 8192
175#define	MJUMPAGESIZE	PAGE_SIZE
176#else
177#define	MJUMPAGESIZE	(8 * 1024)
178#endif
179
180#define	MJUM9BYTES	(9 * 1024)	/* jumbo cluster 9k */
181#define	MJUM16BYTES	(16 * 1024)	/* jumbo cluster 16k */
182
183/*
184 * Some macros for units conversion
185 */
186
187/* clicks to bytes */
188#ifndef ctob
189#define ctob(x)	((x)<<PAGE_SHIFT)
190#endif
191
192/* bytes to clicks */
193#ifndef btoc
194#define btoc(x)	(((vm_offset_t)(x)+PAGE_MASK)>>PAGE_SHIFT)
195#endif
196
197/*
198 * btodb() is messy and perhaps slow because `bytes' may be an off_t.  We
199 * want to shift an unsigned type to avoid sign extension and we don't
200 * want to widen `bytes' unnecessarily.  Assume that the result fits in
201 * a daddr_t.
202 */
203#ifndef btodb
204#define btodb(bytes)	 		/* calculates (bytes / DEV_BSIZE) */ \
205	(sizeof (bytes) > sizeof(long) \
206	 ? (daddr_t)((unsigned long long)(bytes) >> DEV_BSHIFT) \
207	 : (daddr_t)((unsigned long)(bytes) >> DEV_BSHIFT))
208#endif
209
210#ifndef dbtob
211#define dbtob(db)			/* calculates (db * DEV_BSIZE) */ \
212	((off_t)(db) << DEV_BSHIFT)
213#endif
214
215#define	PRIMASK	0x0ff
216#define	PCATCH	0x100		/* OR'd with pri for tsleep to check signals */
217#define	PDROP	0x200	/* OR'd with pri to stop re-entry of interlock mutex */
218
219#define	NZERO	0		/* default "nice" */
220
221#define	NBBY	8		/* number of bits in a byte */
222#define	NBPW	sizeof(int)	/* number of bytes per word (integer) */
223
224#define	CMASK	022		/* default file mask: S_IWGRP|S_IWOTH */
225
226#define	NODEV	(dev_t)(-1)	/* non-existent device */
227
228/*
229 * File system parameters and macros.
230 *
231 * MAXBSIZE -	Filesystems are made out of blocks of at most MAXBSIZE bytes
232 *		per block.  MAXBSIZE may be made larger without effecting
233 *		any existing filesystems as long as it does not exceed MAXPHYS,
234 *		and may be made smaller at the risk of not being able to use
235 *		filesystems which require a block size exceeding MAXBSIZE.
236 *
237 * MAXBCACHEBUF - Maximum size of a buffer in the buffer cache.  This must
238 *		be >= MAXBSIZE and can be set differently for different
239 *		architectures by defining it in <machine/param.h>.
240 *		Making this larger allows NFS to do larger reads/writes.
241 *
242 * BKVASIZE -	Nominal buffer space per buffer, in bytes.  BKVASIZE is the
243 *		minimum KVM memory reservation the kernel is willing to make.
244 *		Filesystems can of course request smaller chunks.  Actual
245 *		backing memory uses a chunk size of a page (PAGE_SIZE).
246 *		The default value here can be overridden on a per-architecture
247 *		basis by defining it in <machine/param.h>.  This should
248 *		probably be done to increase its value, when MAXBCACHEBUF is
249 *		defined as a larger value in <machine/param.h>.
250 *
251 *		If you make BKVASIZE too small you risk seriously fragmenting
252 *		the buffer KVM map which may slow things down a bit.  If you
253 *		make it too big the kernel will not be able to optimally use
254 *		the KVM memory reserved for the buffer cache and will wind
255 *		up with too-few buffers.
256 *
257 *		The default is 16384, roughly 2x the block size used by a
258 *		normal UFS filesystem.
259 */
260#define MAXBSIZE	65536	/* must be power of 2 */
261#ifndef	MAXBCACHEBUF
262#define	MAXBCACHEBUF	MAXBSIZE /* must be a power of 2 >= MAXBSIZE */
263#endif
264#ifndef	BKVASIZE
265#define BKVASIZE	16384	/* must be power of 2 */
266#endif
267#define BKVAMASK	(BKVASIZE-1)
268
269/*
270 * MAXPATHLEN defines the longest permissible path length after expanding
271 * symbolic links. It is used to allocate a temporary buffer from the buffer
272 * pool in which to do the name expansion, hence should be a power of two,
273 * and must be less than or equal to MAXBSIZE.  MAXSYMLINKS defines the
274 * maximum number of symbolic links that may be expanded in a path name.
275 * It should be set high enough to allow all legitimate uses, but halt
276 * infinite loops reasonably quickly.
277 */
278#define	MAXPATHLEN	PATH_MAX
279#define MAXSYMLINKS	32
280
281/* Bit map related macros. */
282#define	setbit(a,i)	(((unsigned char *)(a))[(i)/NBBY] |= 1<<((i)%NBBY))
283#define	clrbit(a,i)	(((unsigned char *)(a))[(i)/NBBY] &= ~(1<<((i)%NBBY)))
284#define	isset(a,i)							\
285	(((const unsigned char *)(a))[(i)/NBBY] & (1<<((i)%NBBY)))
286#define	isclr(a,i)							\
287	((((const unsigned char *)(a))[(i)/NBBY] & (1<<((i)%NBBY))) == 0)
288
289/* Macros for counting and rounding. */
290#ifndef howmany
291#define	howmany(x, y)	(((x)+((y)-1))/(y))
292#endif
293#define	nitems(x)	(sizeof((x)) / sizeof((x)[0]))
294#define	rounddown(x, y)	(((x)/(y))*(y))
295#define	rounddown2(x, y) ((x)&(~((y)-1)))          /* if y is power of two */
296#define	roundup(x, y)	((((x)+((y)-1))/(y))*(y))  /* to any y */
297#define	roundup2(x, y)	(((x)+((y)-1))&(~((y)-1))) /* if y is powers of two */
298#define powerof2(x)	((((x)-1)&(x))==0)
299
300/* Macros for min/max. */
301#define	MIN(a,b) (((a)<(b))?(a):(b))
302#define	MAX(a,b) (((a)>(b))?(a):(b))
303
304#ifdef _KERNEL
305/*
306 * Basic byte order function prototypes for non-inline functions.
307 */
308#ifndef LOCORE
309#ifndef _BYTEORDER_PROTOTYPED
310#define	_BYTEORDER_PROTOTYPED
311__BEGIN_DECLS
312__uint32_t	 htonl(__uint32_t);
313__uint16_t	 htons(__uint16_t);
314__uint32_t	 ntohl(__uint32_t);
315__uint16_t	 ntohs(__uint16_t);
316__END_DECLS
317#endif
318#endif
319
320#ifndef lint
321#ifndef _BYTEORDER_FUNC_DEFINED
322#define	_BYTEORDER_FUNC_DEFINED
323#define	htonl(x)	__htonl(x)
324#define	htons(x)	__htons(x)
325#define	ntohl(x)	__ntohl(x)
326#define	ntohs(x)	__ntohs(x)
327#endif /* !_BYTEORDER_FUNC_DEFINED */
328#endif /* lint */
329#endif /* _KERNEL */
330
331/*
332 * Scale factor for scaled integers used to count %cpu time and load avgs.
333 *
334 * The number of CPU `tick's that map to a unique `%age' can be expressed
335 * by the formula (1 / (2 ^ (FSHIFT - 11))).  The maximum load average that
336 * can be calculated (assuming 32 bits) can be closely approximated using
337 * the formula (2 ^ (2 * (16 - FSHIFT))) for (FSHIFT < 15).
338 *
339 * For the scheduler to maintain a 1:1 mapping of CPU `tick' to `%age',
340 * FSHIFT must be at least 11; this gives us a maximum load avg of ~1024.
341 */
342#define	FSHIFT	11		/* bits to right of fixed binary point */
343#define FSCALE	(1<<FSHIFT)
344
345#define dbtoc(db)			/* calculates devblks to pages */ \
346	((db + (ctodb(1) - 1)) >> (PAGE_SHIFT - DEV_BSHIFT))
347
348#define ctodb(db)			/* calculates pages to devblks */ \
349	((db) << (PAGE_SHIFT - DEV_BSHIFT))
350
351/*
352 * Old spelling of __containerof().
353 */
354#define	member2struct(s, m, x)						\
355	((struct s *)(void *)((char *)(x) - offsetof(struct s, m)))
356
357/*
358 * Access a variable length array that has been declared as a fixed
359 * length array.
360 */
361#define __PAST_END(array, offset) (((__typeof__(*(array)) *)(array))[offset])
362
363#endif	/* _SYS_PARAM_H_ */
364