FreeBSD/Linux Kernel Cross Reference
sys/i386/include/param.h

     /*-
      * 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: releng/5.0/sys/i386/include/param.h 103436 2002-09-17 01:49:00Z peter $
     */
    
    /*
     * Machine dependent constants for Intel 386.
     */
    
    /*
     * 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.
     */
    #ifndef _ALIGNBYTES
    #define _ALIGNBYTES     (sizeof(int) - 1)
    #endif
    #ifndef _ALIGN
    #define _ALIGN(p)       (((unsigned)(p) + _ALIGNBYTES) & ~_ALIGNBYTES)
    #endif
    
    #ifndef _MACHINE
    #define _MACHINE        i386
    #endif
    #ifndef _MACHINE_ARCH
    #define _MACHINE_ARCH   i386
    #endif
    
    #ifndef _NO_NAMESPACE_POLLUTION
    
    #ifndef _MACHINE_PARAM_H_
    #define _MACHINE_PARAM_H_
    
    #ifndef MACHINE
    #define MACHINE         "i386"
    #endif
    #ifndef MACHINE_ARCH
    #define MACHINE_ARCH    "i386"
    #endif
    #define MID_MACHINE     MID_I386
    
    #ifdef SMP
    #define MAXCPU          16
    #else
    #define MAXCPU          1
    #endif /* SMP */
    
    #define ALIGNBYTES      _ALIGNBYTES
    #define ALIGN(p)        _ALIGN(p)
    
    #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 IOPAGES 2               /* pages of i/o permission bitmap */
    
    #ifndef KSTACK_PAGES
    #define KSTACK_PAGES 2          /* Includes pcb! */
    #endif
   #define UAREA_PAGES 1           /* holds struct user WITHOUT PCB (see def.) */
   
   #define KSTACK_GUARD            /* compile in the kstack guard page */
   
   /*
    * Ceiling on amount of swblock kva space, can be changed via
    * the kern.maxswzone /boot/loader.conf variable.
    */
   #ifndef VM_SWZONE_SIZE_MAX
   #define VM_SWZONE_SIZE_MAX      (32 * 1024 * 1024)
   #endif
   
   /*
    * Ceiling on size of buffer cache (really only effects write queueing,
    * the VM page cache is not effected), can be changed via
    * the kern.maxbcache /boot/loader.conf variable.
    */
   #ifndef VM_BCACHE_SIZE_MAX
   #define VM_BCACHE_SIZE_MAX      (200 * 1024 * 1024)
   #endif
   
   /*
    * 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_ */
   #endif /* !_NO_NAMESPACE_POLLUTION */

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