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/* Copyright (C) 1995,1996,1997,2000,2001,2003 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#ifndef _SYS_PARAM_H
# error "Never use <bits/param.h> directly; include <sys/param.h> instead."
#endif
#include <limits.h>
#include <sys/syslimits.h>
/*
* __FreeBSD_version numbers are documented in the Porter's Handbook.
* If you bump the version for any reason, you should update the documentation
* there.
* Currently this lives here:
*
* doc/en_US.ISO8859-1/books/porters-handbook/book.sgml
*
* scheme is: <major><two digit minor><0 if release branch, otherwise 1>xx
*/
#include <osreldate.h>
/* Some inet code expects that this file defines the 'u_int32_t' type. */
#include <stdint.h>
/* FreeBSD code expects that this file implicitly defines SIG* macros. */
#include <signal.h>
/*
* Machine-independent constants (some used in following include files).
* Redefined constants are from POSIX 1003.1 limits file.
*
* MAXCOMLEN should be >= sizeof(ac_comm) (see <acct.h>)
* MAXLOGNAME should be == UT_NAMESIZE+1 (see <utmp.h>)
*/
#define MAXCOMLEN 19 /* max command name remembered */
#define MAXINTERP 32 /* max interpreter file name length */
#define MAXLOGNAME 33 /* max login name length (incl. NUL) */
#define MAXUPRC CHILD_MAX /* max simultaneous processes */
#define NGROUPS (NGROUPS_MAX+1) /* max number groups */
#define MAXHOSTNAMELEN 256 /* max hostname size */
#define SPECNAMELEN 63 /* max length of devicename */
#define TTY_NAME_MAX SPECNAMELEN
/* BSD names for some <limits.h> values. */
#define MAXSYMLINKS 32
#define CANBSIZ MAX_CANON
/* Machine type dependent parameters. */
#include <machine/param.h>
#ifndef BLKDEV_IOSIZE
#define BLKDEV_IOSIZE PAGE_SIZE /* default block device I/O size */
#endif
#ifndef DFLTPHYS
#define DFLTPHYS (64 * 1024) /* default max raw I/O transfer size */
#endif
#ifndef MAXPHYS
#define MAXPHYS (128 * 1024) /* max raw I/O transfer size */
#endif
#ifndef MAXDUMPPGS
#define MAXDUMPPGS (DFLTPHYS/PAGE_SIZE)
#endif
/*
* Constants related to network buffer management.
* MCLBYTES must be no larger than PAGE_SIZE.
*/
#ifndef MSIZE
#define MSIZE 256 /* size of an mbuf */
#endif /* MSIZE */
#ifndef MCLSHIFT
#define MCLSHIFT 11 /* convert bytes to mbuf clusters */
#endif /* MCLSHIFT */
#define MCLBYTES (1 << MCLSHIFT) /* size of an mbuf cluster */
/*
* Some macros for units conversion
*/
/* clicks to bytes */
#ifndef ctob
#define ctob(x) ((x)<<PAGE_SHIFT)
#endif
/* bytes to clicks */
#ifndef btoc
#define btoc(x) (((vm_offset_t)(x)+PAGE_MASK)>>PAGE_SHIFT)
#endif
/*
* btodb() is messy and perhaps slow because `bytes' may be an off_t. We
* want to shift an unsigned type to avoid sign extension and we don't
* want to widen `bytes' unnecessarily. Assume that the result fits in
* a daddr_t.
*/
#ifndef btodb
#define btodb(bytes) /* calculates (bytes / DEV_BSIZE) */ \
(sizeof (bytes) > sizeof(long) \
? (daddr_t)((unsigned long long)(bytes) >> DEV_BSHIFT) \
: (daddr_t)((unsigned long)(bytes) >> DEV_BSHIFT))
#endif
#ifndef dbtob
#define dbtob(db) /* calculates (db * DEV_BSIZE) */ \
((off_t)(db) << DEV_BSHIFT)
#endif
#define PRIMASK 0x0ff
#define PCATCH 0x100 /* OR'd with pri for tsleep to check signals */
#define PDROP 0x200 /* OR'd with pri to stop re-entry of interlock mutex */
#define NBPW sizeof(int) /* number of bytes per word (integer) */
#define CMASK 022 /* default file mask: S_IWGRP|S_IWOTH */
#define NODEV (dev_t)(-1) /* non-existent device */
#define CBLOCK 128 /* Clist block size, must be a power of 2. */
#define CBQSIZE (CBLOCK/NBBY) /* Quote bytes/cblock - can do better. */
/* Data chars/clist. */
#define CBSIZE (CBLOCK - sizeof(struct cblock *) - CBQSIZE)
#define CROUND (CBLOCK - 1) /* Clist rounding. */
/*
* File system parameters and macros.
*
* MAXBSIZE - Filesystems are made out of blocks of at most MAXBSIZE bytes
* per block. MAXBSIZE may be made larger without effecting
* any existing filesystems as long as it does not exceed MAXPHYS,
* and may be made smaller at the risk of not being able to use
* filesystems which require a block size exceeding MAXBSIZE.
*
* BKVASIZE - Nominal buffer space per buffer, in bytes. BKVASIZE is the
* minimum KVM memory reservation the kernel is willing to make.
* Filesystems can of course request smaller chunks. Actual
* backing memory uses a chunk size of a page (PAGE_SIZE).
*
* If you make BKVASIZE too small you risk seriously fragmenting
* the buffer KVM map which may slow things down a bit. If you
* make it too big the kernel will not be able to optimally use
* the KVM memory reserved for the buffer cache and will wind
* up with too-few buffers.
*
* The default is 16384, roughly 2x the block size used by a
* normal UFS filesystem.
*/
#define MAXBSIZE 65536 /* must be power of 2 */
#define BKVASIZE 16384 /* must be power of 2 */
#define BKVAMASK (BKVASIZE-1)
/*
* Scale factor for scaled integers used to count %cpu time and load avgs.
*
* The number of CPU `tick's that map to a unique `%age' can be expressed
* by the formula (1 / (2 ^ (FSHIFT - 11))). The maximum load average that
* can be calculated (assuming 32 bits) can be closely approximated using
* the formula (2 ^ (2 * (16 - FSHIFT))) for (FSHIFT < 15).
*
* For the scheduler to maintain a 1:1 mapping of CPU `tick' to `%age',
* FSHIFT must be at least 11; this gives us a maximum load avg of ~1024.
*/
#define FSHIFT 11 /* bits to right of fixed binary point */
#define FSCALE (1<<FSHIFT)
#define dbtoc(db) /* calculates devblks to pages */ \
((db + (ctodb(1) - 1)) >> (PAGE_SHIFT - DEV_BSHIFT))
#define ctodb(db) /* calculates pages to devblks */ \
((db) << (PAGE_SHIFT - DEV_BSHIFT))
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