Source to mach/i386/vm_param.h

/*
 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * "Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
 * Reserved.  This file contains Original Code and/or Modifications of
 * Original Code as defined in and that are subject to the Apple Public
 * Source License Version 1.0 (the 'License').  You may not use this file
 * except in compliance with the License.  Please obtain a copy of the
 * License at http://www.apple.com/publicsource and read it before using
 * this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License."
 * 
 * @APPLE_LICENSE_HEADER_END@
 */

/*
 * Copyright (c) 1992 NeXT Computer, Inc.
 *
 * Intel386 Family:	Virtual memory constants.
 *
 * HISTORY
 *
 * 14 April 1992 ? at NeXT
 *	Created.
 */

#ifndef	_MACH_I386_VM_PARAM_H_
#define _MACH_I386_VM_PARAM_H_

#import <sys/types.h>

#define BYTE_SIZE	8	/* byte size in bits */
#define BYTE_MSF	0

#define I386_PGBYTES	4096	/* bytes per 80386 page */
#define I386_PGSHIFT	12	/* number of bits to shift for pages */

/*
 *	Convert bytes to pages and convert pages to bytes.
 *	No rounding is used.
 */

#define i386_btop(x)		(((unsigned)(x)) >> I386_PGSHIFT)
#define i386_ptob(x)		(((unsigned)(x)) << I386_PGSHIFT)

/*
 *	Round off or truncate to the nearest page.  These will work
 *	for either addresses or counts.  (i.e. 1 byte rounds to 1 page
 *	bytes.
 */

#define i386_round_page(x)	((((unsigned)(x)) + I386_PGBYTES - 1) & \
					~(I386_PGBYTES-1))
#define i386_trunc_page(x)	(((unsigned)(x)) & ~(I386_PGBYTES-1))

#define VM_MIN_ADDRESS		((vm_offset_t) 0)
#define VM_MAX_ADDRESS		((vm_offset_t) 0xc0000000)

#define VM_MIN_KERNEL_ADDRESS	((vm_offset_t) 0x00000000)
#define VM_MAX_KERNEL_ADDRESS	((vm_offset_t) 0x40000000)

#define KERNSTACK_SIZE		(2*I386_PGBYTES)
#define INTSTACK_SIZE		(1*I386_PGBYTES)

/*
 *	Conversion between 80386 pages and VM pages
 */

#define trunc_i386_to_vm(p)	(atop(trunc_page(i386_ptob(p))))
#define round_i386_to_vm(p)	(atop(round_page(i386_ptob(p))))
#define vm_to_i386(p)		(i386_btop(ptoa(p)))

/*
 * Maximum alignment required by any data type for this architecture.
 * (Use 4 bytes for performance reasons....)
 */
#define	MAX_DATA_ALIGNMENT	4		/* 4 bytes */

#endif	/* _MACH_I386_VM_PARAM_H_ */