freebsd-dev/sys/i386/include/param.h
Matthew Dillon 8b22cebb2c Back out a portion of the last commit. DFLTPHYS and MAXPHYS cannot
be set by a kernel conf option due to the struct buf structural
    dependancy (sizing of b_pages[]) creating a conflict with modules
    (which are not compiled with kernel config options overrides).

    We'll be able to sysctl these two later on when the buffer subsystem
    is revamped.
1999-09-22 05:48:31 +00:00

163 lines
5.5 KiB
C

/*-
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: @(#)param.h 5.8 (Berkeley) 6/28/91
* $FreeBSD$
*/
#ifndef _MACHINE_PARAM_H_
#define _MACHINE_PARAM_H_
/*
* Machine dependent constants for Intel 386.
*/
#ifndef _MACHINE
#define _MACHINE i386
#endif
#ifndef MACHINE
#define MACHINE "i386"
#endif
#ifndef _MACHINE_ARCH
#define _MACHINE_ARCH i386
#endif
#ifndef MACHINE_ARCH
#define MACHINE_ARCH "i386"
#endif
#define MID_MACHINE MID_I386
/*
* OBJFORMAT_NAMES is a comma-separated list of the object formats
* that are supported on the architecture.
*/
#define OBJFORMAT_NAMES "elf", "aout"
#define OBJFORMAT_DEFAULT "elf"
#ifdef SMP
#define NCPUS 2
#else
#define NCPUS 1
#endif
/*
* Round p (pointer or byte index) up to a correctly-aligned value
* for all data types (int, long, ...). The result is unsigned int
* and must be cast to any desired pointer type.
*/
#define ALIGNBYTES (sizeof(int) - 1)
#define ALIGN(p) (((unsigned)(p) + ALIGNBYTES) & ~ALIGNBYTES)
#define PAGE_SHIFT 12 /* LOG2(PAGE_SIZE) */
#define PAGE_SIZE (1<<PAGE_SHIFT) /* bytes/page */
#define PAGE_MASK (PAGE_SIZE-1)
#define NPTEPG (PAGE_SIZE/(sizeof (pt_entry_t)))
#define NPDEPG (PAGE_SIZE/(sizeof (pd_entry_t)))
#define PDRSHIFT 22 /* LOG2(NBPDR) */
#define NBPDR (1<<PDRSHIFT) /* bytes/page dir */
#define PDRMASK (NBPDR-1)
#define DEV_BSHIFT 9 /* log2(DEV_BSIZE) */
#define DEV_BSIZE (1<<DEV_BSHIFT)
#ifndef BLKDEV_IOSIZE
#define BLKDEV_IOSIZE PAGE_SIZE /* default block device I/O size */
#endif
#define DFLTPHYS (64 * 1024) /* default max raw I/O transfer size */
#define MAXPHYS (128 * 1024) /* max raw I/O transfer size */
#define IOPAGES 2 /* pages of i/o permission bitmap */
#define UPAGES 2 /* pages of u-area */
#define UPAGES_HOLE 2 /* pages of "hole" at top of user space where */
/* the upages used to be. DO NOT CHANGE! */
/*
* Constants related to network buffer management.
* MCLBYTES must be no larger than CLBYTES (the software page size), and,
* on machines that exchange pages of input or output buffers with mbuf
* clusters (MAPPED_MBUFS), MCLBYTES must also be an integral multiple
* of the hardware page size.
*/
#ifndef MSIZE
#define MSIZE 128 /* size of an mbuf */
#endif /* MSIZE */
#ifndef MCLSHIFT
#define MCLSHIFT 11 /* convert bytes to m_buf clusters */
#endif /* MCLSHIFT */
#define MCLBYTES (1 << MCLSHIFT) /* size of an m_buf cluster */
#define MCLOFSET (MCLBYTES - 1) /* offset within an m_buf cluster */
/*
* Some macros for units conversion
*/
/* clicks to bytes */
#define ctob(x) ((x)<<PAGE_SHIFT)
/* bytes to clicks */
#define btoc(x) (((unsigned)(x)+PAGE_MASK)>>PAGE_SHIFT)
/*
* 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.
*/
#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))
#define dbtob(db) /* calculates (db * DEV_BSIZE) */ \
((off_t)(db) << DEV_BSHIFT)
/*
* Mach derived conversion macros
*/
#define trunc_page(x) ((x) & ~PAGE_MASK)
#define round_page(x) (((x) + PAGE_MASK) & ~PAGE_MASK)
#define trunc_4mpage(x) ((unsigned)(x) & ~PDRMASK)
#define round_4mpage(x) ((((unsigned)(x)) + PDRMASK) & ~PDRMASK)
#define atop(x) ((unsigned)(x) >> PAGE_SHIFT)
#define ptoa(x) ((unsigned)(x) << PAGE_SHIFT)
#define i386_btop(x) ((unsigned)(x) >> PAGE_SHIFT)
#define i386_ptob(x) ((unsigned)(x) << PAGE_SHIFT)
#define pgtok(x) ((x) * (PAGE_SIZE / 1024))
#endif /* !_MACHINE_PARAM_H_ */