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/*- 
 * Copyright (c) 1982, 1986, 1993 
 *	The Regents of the University of California.  All rights reserved. 
 * (c) UNIX System Laboratories, Inc. 
 * All or some portions of this file are derived from material licensed 
 * to the University of California by American Telephone and Telegraph 
 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 
 * the permission of UNIX System Laboratories, Inc. 
 * 
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 * 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 
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
 * SUCH DAMAGE. 
 * 
 *	@(#)map.h	8.3 (Berkeley) 1/26/94 
 */ 
 
/* 
 * Resource allocation maps. 
 * 
 * Associated routines manage sub-allocation of an address space using 
 * an array of segment descriptors.  The first element of this array 
 * is a map structure, describing the arrays extent and the name 
 * of the controlled object.  Each additional structure represents 
 * a free segment of the address space. 
 * 
 * A call to rminit initializes a resource map and may also be used 
 * to free some address space for the map.  Subsequent calls to rmalloc 
 * and rmfree allocate and free space in the resource map.  If the resource 
 * map becomes too fragmented to be described in the available space, 
 * then some of the resource is discarded.  This may lead to critical 
 * shortages, but is better than not checking (as the previous versions 
 * of these routines did) or giving up and calling panic().  The routines 
 * could use linked lists and call a memory allocator when they run 
 * out of space, but that would not solve the out of space problem when 
 * called at interrupt time. 
 * 
 * N.B.: The address 0 in the resource address space is not available 
 * as it is used internally by the resource map routines. 
 */ 
struct map { 
	struct	mapent *m_limit;	/* address of last slot in map */ 
	char	*m_name;		/* name of resource, for messages */ 
}; 
 
struct mapent { 
	long	m_size;			/* size of this segment of the map */ 
	long	m_addr;			/* start of segment */ 
}; 
 
#ifdef KERNEL 
#define	ARGMAPSIZE	16 
struct	map *kmemmap, *mbmap, *swapmap; 
int	nswapmap; 
 
long	rmalloc __P((struct map *, long)); 
void	rmfree __P((struct map *, long, long)); 
void	rminit __P((struct map *, long, long, char *, int)); 
#endif