FreeBSD/Linux Kernel Cross Reference
sys/sys/param.h
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: releng/8.3/sys/sys/param.h 232446 2012-03-03 07:09:05Z kensmith $
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:
52 *
53 * doc/en_US.ISO8859-1/books/porters-handbook/book.sgml
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 803000 /* 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 #endif
84
85 #ifndef LOCORE
86 #include <sys/types.h>
87 #endif
88
89 /*
90 * Machine-independent constants (some used in following include files).
91 * Redefined constants are from POSIX 1003.1 limits file.
92 *
93 * MAXCOMLEN should be >= sizeof(ac_comm) (see <acct.h>)
94 * MAXLOGNAME should be == UT_NAMESIZE+1 (see <utmp.h>)
95 */
96 #include <sys/syslimits.h>
97
98 #define MAXCOMLEN 19 /* max command name remembered */
99 #define MAXINTERP 32 /* max interpreter file name length */
100 #define MAXLOGNAME 17 /* max login name length (incl. NUL) */
101 #define MAXUPRC CHILD_MAX /* max simultaneous processes */
102 #define NCARGS ARG_MAX /* max bytes for an exec function */
103 #define NGROUPS (NGROUPS_MAX+1) /* max number groups */
104 #define NOFILE OPEN_MAX /* max open files per process */
105 #define NOGROUP 65535 /* marker for empty group set member */
106 #define MAXHOSTNAMELEN 256 /* max hostname size */
107 #define SPECNAMELEN 63 /* max length of devicename */
108
109 /* More types and definitions used throughout the kernel. */
110 #ifdef _KERNEL
111 #include <sys/cdefs.h>
112 #include <sys/errno.h>
113 #ifndef LOCORE
114 #include <sys/time.h>
115 #include <sys/priority.h>
116 #endif
117
118 #ifndef FALSE
119 #define FALSE 0
120 #endif
121 #ifndef TRUE
122 #define TRUE 1
123 #endif
124 #endif
125
126 #ifndef _KERNEL
127 /* Signals. */
128 #include <sys/signal.h>
129 #endif
130
131 /* Machine type dependent parameters. */
132 #include <machine/param.h>
133 #ifndef _KERNEL
134 #include <sys/limits.h>
135 #endif
136
137 #ifndef _NO_NAMESPACE_POLLUTION
138
139 #ifndef DEV_BSHIFT
140 #define DEV_BSHIFT 9 /* log2(DEV_BSIZE) */
141 #endif
142 #define DEV_BSIZE (1<<DEV_BSHIFT)
143
144 #ifndef BLKDEV_IOSIZE
145 #define BLKDEV_IOSIZE PAGE_SIZE /* default block device I/O size */
146 #endif
147 #ifndef DFLTPHYS
148 #define DFLTPHYS (64 * 1024) /* default max raw I/O transfer size */
149 #endif
150 #ifndef MAXPHYS
151 #define MAXPHYS (128 * 1024) /* max raw I/O transfer size */
152 #endif
153 #ifndef MAXDUMPPGS
154 #define MAXDUMPPGS (DFLTPHYS/PAGE_SIZE)
155 #endif
156
157 /*
158 * Constants related to network buffer management.
159 * MCLBYTES must be no larger than PAGE_SIZE.
160 */
161 #ifndef MSIZE
162 #define MSIZE 256 /* size of an mbuf */
163 #endif /* MSIZE */
164
165 #ifndef MCLSHIFT
166 #define MCLSHIFT 11 /* convert bytes to mbuf clusters */
167 #endif /* MCLSHIFT */
168
169 #define MCLBYTES (1 << MCLSHIFT) /* size of an mbuf cluster */
170
171 #define MJUMPAGESIZE PAGE_SIZE /* jumbo cluster 4k */
172 #define MJUM9BYTES (9 * 1024) /* jumbo cluster 9k */
173 #define MJUM16BYTES (16 * 1024) /* jumbo cluster 16k */
174
175 /*
176 * Some macros for units conversion
177 */
178
179 /* clicks to bytes */
180 #ifndef ctob
181 #define ctob(x) ((x)<<PAGE_SHIFT)
182 #endif
183
184 /* bytes to clicks */
185 #ifndef btoc
186 #define btoc(x) (((vm_offset_t)(x)+PAGE_MASK)>>PAGE_SHIFT)
187 #endif
188
189 /*
190 * btodb() is messy and perhaps slow because `bytes' may be an off_t. We
191 * want to shift an unsigned type to avoid sign extension and we don't
192 * want to widen `bytes' unnecessarily. Assume that the result fits in
193 * a daddr_t.
194 */
195 #ifndef btodb
196 #define btodb(bytes) /* calculates (bytes / DEV_BSIZE) */ \
197 (sizeof (bytes) > sizeof(long) \
198 ? (daddr_t)((unsigned long long)(bytes) >> DEV_BSHIFT) \
199 : (daddr_t)((unsigned long)(bytes) >> DEV_BSHIFT))
200 #endif
201
202 #ifndef dbtob
203 #define dbtob(db) /* calculates (db * DEV_BSIZE) */ \
204 ((off_t)(db) << DEV_BSHIFT)
205 #endif
206
207 #endif /* _NO_NAMESPACE_POLLUTION */
208
209 #define PRIMASK 0x0ff
210 #define PCATCH 0x100 /* OR'd with pri for tsleep to check signals */
211 #define PDROP 0x200 /* OR'd with pri to stop re-entry of interlock mutex */
212 #define PBDRY 0x400 /* for PCATCH stop is done on the user boundary */
213
214 #define NZERO 0 /* default "nice" */
215
216 #define NBBY 8 /* number of bits in a byte */
217 #define NBPW sizeof(int) /* number of bytes per word (integer) */
218
219 #define CMASK 022 /* default file mask: S_IWGRP|S_IWOTH */
220
221 #define NODEV (dev_t)(-1) /* non-existent device */
222
223 /*
224 * File system parameters and macros.
225 *
226 * MAXBSIZE - Filesystems are made out of blocks of at most MAXBSIZE bytes
227 * per block. MAXBSIZE may be made larger without effecting
228 * any existing filesystems as long as it does not exceed MAXPHYS,
229 * and may be made smaller at the risk of not being able to use
230 * filesystems which require a block size exceeding MAXBSIZE.
231 *
232 * BKVASIZE - Nominal buffer space per buffer, in bytes. BKVASIZE is the
233 * minimum KVM memory reservation the kernel is willing to make.
234 * Filesystems can of course request smaller chunks. Actual
235 * backing memory uses a chunk size of a page (PAGE_SIZE).
236 *
237 * If you make BKVASIZE too small you risk seriously fragmenting
238 * the buffer KVM map which may slow things down a bit. If you
239 * make it too big the kernel will not be able to optimally use
240 * the KVM memory reserved for the buffer cache and will wind
241 * up with too-few buffers.
242 *
243 * The default is 16384, roughly 2x the block size used by a
244 * normal UFS filesystem.
245 */
246 #define MAXBSIZE 65536 /* must be power of 2 */
247 #define BKVASIZE 16384 /* must be power of 2 */
248 #define BKVAMASK (BKVASIZE-1)
249
250 /*
251 * MAXPATHLEN defines the longest permissible path length after expanding
252 * symbolic links. It is used to allocate a temporary buffer from the buffer
253 * pool in which to do the name expansion, hence should be a power of two,
254 * and must be less than or equal to MAXBSIZE. MAXSYMLINKS defines the
255 * maximum number of symbolic links that may be expanded in a path name.
256 * It should be set high enough to allow all legitimate uses, but halt
257 * infinite loops reasonably quickly.
258 */
259 #define MAXPATHLEN PATH_MAX
260 #define MAXSYMLINKS 32
261
262 /* Bit map related macros. */
263 #define setbit(a,i) (((unsigned char *)(a))[(i)/NBBY] |= 1<<((i)%NBBY))
264 #define clrbit(a,i) (((unsigned char *)(a))[(i)/NBBY] &= ~(1<<((i)%NBBY)))
265 #define isset(a,i) \
266 (((const unsigned char *)(a))[(i)/NBBY] & (1<<((i)%NBBY)))
267 #define isclr(a,i) \
268 ((((const unsigned char *)(a))[(i)/NBBY] & (1<<((i)%NBBY))) == 0)
269
270 /* Macros for counting and rounding. */
271 #ifndef howmany
272 #define howmany(x, y) (((x)+((y)-1))/(y))
273 #endif
274 #define rounddown(x, y) (((x)/(y))*(y))
275 #define roundup(x, y) ((((x)+((y)-1))/(y))*(y)) /* to any y */
276 #define roundup2(x, y) (((x)+((y)-1))&(~((y)-1))) /* if y is powers of two */
277 #define powerof2(x) ((((x)-1)&(x))==0)
278
279 /* Macros for min/max. */
280 #define MIN(a,b) (((a)<(b))?(a):(b))
281 #define MAX(a,b) (((a)>(b))?(a):(b))
282
283 #ifdef _KERNEL
284 /*
285 * Basic byte order function prototypes for non-inline functions.
286 */
287 #ifndef LOCORE
288 #ifndef _BYTEORDER_PROTOTYPED
289 #define _BYTEORDER_PROTOTYPED
290 __BEGIN_DECLS
291 __uint32_t htonl(__uint32_t);
292 __uint16_t htons(__uint16_t);
293 __uint32_t ntohl(__uint32_t);
294 __uint16_t ntohs(__uint16_t);
295 __END_DECLS
296 #endif
297 #endif
298
299 #ifndef lint
300 #ifndef _BYTEORDER_FUNC_DEFINED
301 #define _BYTEORDER_FUNC_DEFINED
302 #define htonl(x) __htonl(x)
303 #define htons(x) __htons(x)
304 #define ntohl(x) __ntohl(x)
305 #define ntohs(x) __ntohs(x)
306 #endif /* !_BYTEORDER_FUNC_DEFINED */
307 #endif /* lint */
308 #endif /* _KERNEL */
309
310 /*
311 * Scale factor for scaled integers used to count %cpu time and load avgs.
312 *
313 * The number of CPU `tick's that map to a unique `%age' can be expressed
314 * by the formula (1 / (2 ^ (FSHIFT - 11))). The maximum load average that
315 * can be calculated (assuming 32 bits) can be closely approximated using
316 * the formula (2 ^ (2 * (16 - FSHIFT))) for (FSHIFT < 15).
317 *
318 * For the scheduler to maintain a 1:1 mapping of CPU `tick' to `%age',
319 * FSHIFT must be at least 11; this gives us a maximum load avg of ~1024.
320 */
321 #define FSHIFT 11 /* bits to right of fixed binary point */
322 #define FSCALE (1<<FSHIFT)
323
324 #define dbtoc(db) /* calculates devblks to pages */ \
325 ((db + (ctodb(1) - 1)) >> (PAGE_SHIFT - DEV_BSHIFT))
326
327 #define ctodb(db) /* calculates pages to devblks */ \
328 ((db) << (PAGE_SHIFT - DEV_BSHIFT))
329
330 /*
331 * Given the pointer x to the member m of the struct s, return
332 * a pointer to the containing structure.
333 */
334 #define member2struct(s, m, x) \
335 ((struct s *)(void *)((char *)(x) - offsetof(struct s, m)))
336
337 #endif /* _SYS_PARAM_H_ */
Cache object: ac3ca569a879921328a57bf2ae38d434
|