xref: /dragonfly/sys/sys/param.h (revision 030b3383)
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  * 300200 - 3.2 release
95  * 300300 - 3.3 master
96  * 300301 - Add eaccess syscall
97  * 300302 - fpsave changes - ucontext_t, mcontext_t, sigcontext, sigframe
98  * 300303 - Demarcation of old m4/flex with new m4/flex
99  * 300304 - Update to dialog-1.2-20121230
100  * 300400 - 3.4 release
101  * 300500 - 3.5 master
102  * 300501 - Convert libm to FreeBSD's version
103  * 300502 - GEM and i915 KMS support in kernel
104  * 300503 - Upgrade libiconv, locales, and associated libc functions
105  * 300600 - 3.6 release
106  * 300700 - 3.7 master
107  * 300701 - Relocate bus/smbus/smb.h to dev/smbus/smb/smb.h
108  * 300702 - drm/i915 update
109  * 300703 - Make usb4bsd default
110  * 300704 - Removal of IPX, NCP and NWFS support
111  * 300705 - Removal of ATM support.
112  * 300800 - 3.8 release
113  * 300900 - 3.9 master
114  * 300901 - drm/i915 hardware context support added
115  * 400000 - 4.0 release
116  * 400100 - 4.1 development
117  * 400101 - Removal of SCTP support.
118  * 400102 - Sound system update from FreeBSD
119  * 400103 - Milestone - availability of gcc50 in base
120  * 400104 - struct lwp_params (a public struct) members renaming
121  * 400105 - Switch to gcc50 as the primary compiler
122  * 400106 - Added pipe2() system call
123  * 400107 - Add futimens() and utimensat() syscalls
124  * 400200 - 4.2 release
125  * 400300 - 4.3 development
126  * 400301 - posix compliant iconv (no const qualifier)
127  * 400302 - Replacement of libm with OpenBSD's libm
128  * 400303 - environ and __progname are no longer linkable symbols
129  * 400304 - Activate symbol versioning for libc.so (still on version 8)
130  * 400305 - Add accept4() system call
131  * 400306 - Add libexecinfo to base
132  * 400307 - drm/i915 kernel module renamed to i915.ko
133  * 400308 - <malloc.h> removal
134  * 400309 - Add lwp_setname() system call
135  * 400400 - 4.4 release
136  * 400500 - 4.5 development
137  * 400501 - unionfs removal
138  */
139 #undef __DragonFly_version
140 #define __DragonFly_version 400501	/* propagated to newvers */
141 
142 #include <sys/_null.h>
143 
144 #ifndef LOCORE
145 #include <sys/types.h>
146 #endif
147 
148 /*
149  * Machine-independent constants (some used in following include files).
150  * Redefined constants are from POSIX 1003.1 limits file.
151  *
152  * MAXCOMLEN should be >= sizeof(ac_comm) (see <acct.h>)
153  * MAXLOGNAME should be == UT_NAMESIZE+1 (see <utmp.h>)
154  */
155 #include <sys/syslimits.h>
156 
157 #define MAXCOMLEN	16		/* max command name remembered */
158 #define MAXINTERP	32		/* max interpreter file name length */
159 #define MAXLOGNAME	17		/* max login name length (incl. NUL) */
160 #define MAXUPRC		CHILD_MAX	/* max simultaneous processes */
161 #define NCARGS		ARG_MAX		/* max bytes for an exec function */
162 #define NGROUPS		NGROUPS_MAX	/* max number groups */
163 #define NOFILE		OPEN_MAX	/* max open files per process */
164 #define NOGROUP		65535		/* marker for empty group set member */
165 #define MAXHOSTNAMELEN	256		/* max hostname size */
166 
167 /* More types and definitions used throughout the kernel. */
168 #ifdef _KERNEL
169 #include <sys/cdefs.h>
170 #include <sys/errno.h>
171 #include <sys/time.h>
172 
173 #define FALSE	0
174 #define TRUE	1
175 #endif
176 
177 #ifndef _KERNEL
178 /* Signals. */
179 #include <sys/select.h>
180 #include <sys/signal.h>
181 #endif
182 
183 /* Machine type dependent parameters. */
184 #include <machine/param.h>
185 #ifndef _KERNEL
186 #include <machine/limits.h>
187 #endif
188 
189 /*
190  * WARNING! Max supported cpu's due to PWAKEUP_CPUMASK is 16384.
191  */
192 #define PCATCH		0x00000100	/* tsleep checks signals */
193 #define PUSRFLAG1	0x00000200	/* Subsystem specific flag */
194 #define PINTERLOCKED	0x00000400	/* Interlocked tsleep */
195 #define PWAKEUP_CPUMASK	0x00003FFF	/* start cpu for chained wakeups */
196 #define PWAKEUP_MYCPU	0x00004000	/* wakeup on current cpu only */
197 #define PWAKEUP_ONE	0x00008000	/* argument to wakeup: only one */
198 #define PDOMAIN_MASK	0xFFFF0000	/* address domains for wakeup */
199 #define PDOMAIN_UMTX	0x00010000	/* independant domain for UMTX */
200 #define PDOMAIN_XLOCK	0x00020000	/* independant domain for fifo_lock */
201 #define PWAKEUP_ENCODE(domain, cpu)	((domain) | (cpu))
202 #define PWAKEUP_DECODE(domain)		((domain) & PWAKEUP_CPUMASK)
203 
204 #define NZERO	0		/* default "nice" */
205 
206 #define NBPW	sizeof(int)	/* number of bytes per word (integer) */
207 
208 #define CMASK	022		/* default file mask: S_IWGRP|S_IWOTH */
209 #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
210 #define NOUDEV	(udev_t)(-1)	/* non-existent device */
211 #define NOMAJ	256		/* non-existent device */
212 #endif
213 
214 #ifndef _KERNEL
215 #define NODEV	(dev_t)(-1)	/* non-existent device */
216 #endif
217 
218 /*
219  * cpu_mi_feature bits
220  */
221 #define CPU_MI_BZERONT	0x00000001
222 #define CPU_MI_MONITOR	0x00000010
223 
224 /*
225  * File system parameters and macros.
226  *
227  * MAXBSIZE -	Filesystems are made out of blocks of at most MAXBSIZE bytes
228  *		per block.  MAXBSIZE may be made larger without effecting
229  *		any existing filesystems as long as it does not exceed MAXPHYS,
230  *		and may be made smaller at the risk of not being able to use
231  *		filesystems which require a block size exceeding MAXBSIZE.
232  *
233  * BKVASIZE -	Nominal buffer space per buffer, in bytes.  BKVASIZE is the
234  *		minimum KVM memory reservation the kernel is willing to make.
235  *		Filesystems can of course request smaller chunks.  Actual
236  *		backing memory uses a chunk size of a page (PAGE_SIZE).
237  *
238  *		If you make BKVASIZE too small you risk seriously fragmenting
239  *		the buffer KVM map which may slow things down a bit.  If you
240  *		make it too big the kernel will not be able to optimally use
241  *		the KVM memory reserved for the buffer cache and will wind
242  *		up with too-few buffers.
243  *
244  *		By default we now use maximally-sized reservations.  But on
245  *		32-bit machines we reduce this 16KB.  Maximally-sized
246  *		reservations greatly reduces defragmentation and buffer_map
247  *		messing around and is more SMP-friendly.
248  */
249 #define MAXBSIZE	65536		/* must be power of 2 */
250 #ifndef BKVASIZE
251 #define BKVASIZE	MAXBSIZE	/* must be power of 2 */
252 #endif
253 
254 #define BKVAMASK	(BKVASIZE-1)
255 #define MAXFRAG 	8
256 
257 /*
258  * MAXPATHLEN defines the longest permissible path length after expanding
259  * symbolic links. It is used to allocate a temporary buffer from the buffer
260  * pool in which to do the name expansion, hence should be a power of two,
261  * and must be less than or equal to MAXBSIZE.  MAXSYMLINKS defines the
262  * maximum number of symbolic links that may be expanded in a path name.
263  * It should be set high enough to allow all legitimate uses, but halt
264  * infinite loops reasonably quickly.
265  */
266 #define MAXPATHLEN	PATH_MAX
267 #define MAXSYMLINKS	32
268 
269 /* Bit map related macros. */
270 #define setbit(a,i)	((a)[(i)/NBBY] |= 1<<((i)%NBBY))
271 #define clrbit(a,i)	((a)[(i)/NBBY] &= ~(1<<((i)%NBBY)))
272 #define isset(a,i)	((a)[(i)/NBBY] & (1<<((i)%NBBY)))
273 #define isclr(a,i)	(((a)[(i)/NBBY] & (1<<((i)%NBBY))) == 0)
274 
275 /* Macros for counting and rounding. */
276 #ifndef howmany
277 #define howmany(x, y)	(((x)+((y)-1))/(y))
278 #endif
279 #define nitems(x)	(sizeof((x)) / sizeof((x)[0]))
280 #define rounddown(x, y)	(((x)/(y))*(y))
281 #define rounddown2(x, y) ((x) & ~((y) - 1))	   /* y power of two */
282 #define roundup(x, y)	((((x)+((y)-1))/(y))*(y))  /* to any y */
283 #define roundup2(x, y)	(((x)+((y)-1))&(~((y)-1))) /* if y is powers of two */
284 #define powerof2(x)	((((x)-1)&(x))==0)
285 
286 /*
287  * VM objects can be larger than the virtual address space, make sure
288  * we don't cut-off the mask.
289  */
290 #define trunc_page64(x)           ((x) & ~(int64_t)PAGE_MASK)
291 #define round_page64(x)           (((x) + PAGE_MASK) & ~(int64_t)PAGE_MASK)
292 
293 /* Macros for min/max. */
294 #define MIN(a,b) (((a)<(b))?(a):(b))
295 #define MAX(a,b) (((a)>(b))?(a):(b))
296 
297 /* Macro for array size */
298 #define NELEM(ary) 	(sizeof(ary) / sizeof((ary)[0]))
299 
300 /*
301  * Constants for setting the parameters of the kernel memory allocator.
302  *
303  * 2 ** MINBUCKET is the smallest unit of memory that will be
304  * allocated. It must be at least large enough to hold a pointer.
305  *
306  * Units of memory less or equal to MAXALLOCSAVE will permanently
307  * allocate physical memory; requests for these size pieces of
308  * memory are quite fast. Allocations greater than MAXALLOCSAVE must
309  * always allocate and free physical memory; requests for these
310  * size allocations should be done infrequently as they will be slow.
311  *
312  * Constraints: PAGE_SIZE <= MAXALLOCSAVE <= 2 ** (MINBUCKET + 14), and
313  * MAXALLOCSIZE must be a power of two.
314  */
315 #define MINBUCKET	4		/* 4 => min allocation of 16 bytes */
316 #define MAXALLOCSAVE	(2 * PAGE_SIZE)
317 
318 /*
319  * Scale factor for scaled integers used to count %cpu time and load avgs.
320  *
321  * The number of CPU `tick's that map to a unique `%age' can be expressed
322  * by the formula (1 / (2 ^ (FSHIFT - 11))).  The maximum load average that
323  * can be calculated (assuming 32 bits) can be closely approximated using
324  * the formula (2 ^ (2 * (16 - FSHIFT))) for (FSHIFT < 15).
325  *
326  * For the scheduler to maintain a 1:1 mapping of CPU `tick' to `%age',
327  * FSHIFT must be at least 11; this gives us a maximum load avg of ~1024.
328  */
329 #define FSHIFT	11		/* bits to right of fixed binary point */
330 #define FSCALE	(1<<FSHIFT)
331 
332 #define dbtoc(db)			/* calculates devblks to pages */ \
333 	((db + (ctodb(1) - 1)) >> (PAGE_SHIFT - DEV_BSHIFT))
334 
335 #define ctodb(db)			/* calculates pages to devblks */ \
336 	((db) << (PAGE_SHIFT - DEV_BSHIFT))
337 
338 #define MJUMPAGESIZE	PAGE_SIZE	/* jumbo cluster 4k */
339 #define MJUM9BYTES	(9 * 1024)	/* jumbo cluster 9k */
340 #define MJUM16BYTES	(16 * 1024)	/* jumbo cluster 16k */
341 
342 /*
343  * MBUF Management.
344  *
345  * Because many drivers can't deal with multiple DMA segments all mbufs
346  * must avoid crossing a page boundary.  While we can accomodate mbufs
347  * which are not a power-of-2 sized kmalloc() will only guarantee
348  * non-crossing alignment if we use a power-of-2.  256 is no longer large
349  * enough due to m_hdr and m_pkthdr bloat.
350  *
351  * MCLBYTES must be a power of 2 and is typically significantly larger
352  * than MSIZE, sufficient to hold a standard-mtu packet.  2K is considered
353  * reasonable.
354  */
355 #ifndef MSIZE
356 #define MSIZE		512		/* size of an mbuf */
357 #endif
358 
359 #ifndef MCLSHIFT
360 #define MCLSHIFT        11              /* convert bytes to m_buf clusters */
361 #endif
362 #define MCLBYTES        (1 << MCLSHIFT) /* size of an m_buf cluster */
363 #define MCLOFSET        (MCLBYTES - 1)  /* offset within an m_buf cluster */
364 
365 /*
366  * Make this available for most of the kernel.  There were too many
367  * things that included sys/systm.h just for panic().
368  */
369 #ifdef _KERNEL
370 void	panic (const char *, ...) __dead2 __printflike(1, 2);
371 #endif
372 
373 #ifndef htonl
374 #define	htonl(x)	__htonl(x)
375 #endif
376 #ifndef htons
377 #define	htons(x)	__htons(x)
378 #endif
379 #ifndef ntohl
380 #define	ntohl(x)	__ntohl(x)
381 #endif
382 #ifndef ntohs
383 #define	ntohs(x)	__ntohs(x)
384 #endif
385 
386 /*
387  * Access a variable length array that has been declared as a fixed
388  * length array.
389  */
390 #define	__PAST_END(array, offset) (((__typeof__(*(array)) *)(array))[offset])
391 
392 #endif	/* _SYS_PARAM_H_ */
393