[unix-history] / sys / vm / swap_pager.h

/*
 * Copyright (c) 1990 University of Utah.
 * Copyright (c) 1991 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * the Systems Programming Group of the University of Utah Computer
 * Science Department.
 *
 * 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: @(#)swap_pager.h	7.1 (Berkeley) 12/5/90
 *	$Id: swap_pager.h,v 1.8 1994/03/07 11:39:10 davidg Exp $
 */

/*
 * Modifications to the block allocation data structure by John S. Dyson
 * 18 Dec 93.
 */

#ifndef	_SWAP_PAGER_
#define	_SWAP_PAGER_	1

/*
 * SWB_NPAGES can be set to any value from 1 to 16 pages per allocation,
 * however, due to the allocation spilling into non-swap pager backed memory,
 * suggest keeping SWB_NPAGES small (1-4).  If high performance is manditory
 * perhaps up to 8 pages might be in order????
 * Above problem has been fixed, now we support 16 pages per block.  Unused
 * space is recovered by the swap pager now...
 */
#define SWB_NPAGES 8
struct	swblock {
	unsigned short swb_valid;	/* bitmask for valid pages */
	unsigned short swb_locked;	/* block locked */
	int	 swb_block[SWB_NPAGES];	/* unfortunately int instead of daddr_t */
};
typedef struct swblock	*sw_blk_t;

/*
 * Swap pager private data.
 */
struct swpager {
	vm_size_t    sw_osize;	/* size of object we are backing (bytes) */
	int	     sw_nblocks;/* number of blocks in list (sw_blk_t units) */
	sw_blk_t     sw_blocks;	/* pointer to list of swap blocks */
	short	     sw_flags;	/* flags */
	short	     sw_poip;	/* pageouts in progress */
	short	     sw_piip;	/* pageins in progress */
};
typedef struct swpager	*sw_pager_t;

#define	SW_WANTED	0x01
#define SW_NAMED	0x02

#ifdef KERNEL

void		swap_pager_init(void);
vm_pager_t	swap_pager_alloc(caddr_t, vm_size_t, vm_prot_t, vm_offset_t);
void		swap_pager_dealloc(vm_pager_t);
boolean_t	swap_pager_getpage(vm_pager_t, vm_page_t, boolean_t);
boolean_t	swap_pager_putpage(vm_pager_t, vm_page_t, boolean_t);
boolean_t	swap_pager_getmulti(vm_pager_t, vm_page_t *, int, int, boolean_t);
boolean_t	swap_pager_haspage(vm_pager_t, vm_offset_t);
int		swap_pager_io(sw_pager_t, vm_page_t *, int, int, int);
void		swap_pager_iodone(struct buf *);
boolean_t	swap_pager_clean();

extern struct pagerops swappagerops;

#endif

#endif	/* _SWAP_PAGER_ */
Commit	Line	Data
15637ed4 RG	1	/*
	2	* Copyright (c) 1990 University of Utah.
	3	* Copyright (c) 1991 The Regents of the University of California.
	4	* All rights reserved.
	5	*
	6	* This code is derived from software contributed to Berkeley by
	7	* the Systems Programming Group of the University of Utah Computer
	8	* Science Department.
	9	*
	10	* Redistribution and use in source and binary forms, with or without
	11	* modification, are permitted provided that the following conditions
	12	* are met:
	13	* 1. Redistributions of source code must retain the above copyright
	14	* notice, this list of conditions and the following disclaimer.
	15	* 2. Redistributions in binary form must reproduce the above copyright
	16	* notice, this list of conditions and the following disclaimer in the
	17	* documentation and/or other materials provided with the distribution.
	18	* 3. All advertising materials mentioning features or use of this software
	19	* must display the following acknowledgement:
	20	* This product includes software developed by the University of
	21	* California, Berkeley and its contributors.
	22	* 4. Neither the name of the University nor the names of its contributors
	23	* may be used to endorse or promote products derived from this software
	24	* without specific prior written permission.
	25	*
	26	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	27	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	28	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	29	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	30	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	31	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	32	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	33	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	34	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	35	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	36	* SUCH DAMAGE.
	37	*
1284e777	38	* from: @(#)swap_pager.h 7.1 (Berkeley) 12/5/90
41aefbec	39	* $Id: swap_pager.h,v 1.8 1994/03/07 11:39:10 davidg Exp $
736d20f2 DG	40	*/
	41
	42	/*
	43	* Modifications to the block allocation data structure by John S. Dyson
	44	* 18 Dec 93.
15637ed4 RG	45	*/
	46
	47	#ifndef _SWAP_PAGER_
	48	#define _SWAP_PAGER_ 1
	49
	50	/*
41aefbec	51	* SWB_NPAGES can be set to any value from 1 to 16 pages per allocation,
736d20f2 DG	52	* however, due to the allocation spilling into non-swap pager backed memory,
	53	* suggest keeping SWB_NPAGES small (1-4). If high performance is manditory
	54	* perhaps up to 8 pages might be in order????
55768178 DG	55	* Above problem has been fixed, now we support 16 pages per block. Unused
55768178 DG	56	* space is recovered by the swap pager now...
15637ed4	57	*/
55768178	58	#define SWB_NPAGES 8
15637ed4	59	struct swblock {
41aefbec DG	60	unsigned short swb_valid; /* bitmask for valid pages */
41aefbec DG	61	unsigned short swb_locked; /* block locked */
736d20f2	62	int swb_block[SWB_NPAGES]; /* unfortunately int instead of daddr_t */
15637ed4 RG	63	};
	64	typedef struct swblock *sw_blk_t;
	65
	66	/*
	67	* Swap pager private data.
	68	*/
	69	struct swpager {
	70	vm_size_t sw_osize; /* size of object we are backing (bytes) */
15637ed4 RG	71	int sw_nblocks;/* number of blocks in list (sw_blk_t units) */
	72	sw_blk_t sw_blocks; /* pointer to list of swap blocks */
	73	short sw_flags; /* flags */
	74	short sw_poip; /* pageouts in progress */
55768178	75	short sw_piip; /* pageins in progress */
15637ed4 RG	76	};
	77	typedef struct swpager *sw_pager_t;
	78
	79	#define SW_WANTED 0x01
	80	#define SW_NAMED 0x02
	81
	82	#ifdef KERNEL
	83
4c45483e	84	void swap_pager_init(void);
ce619eaa	85	vm_pager_t swap_pager_alloc(caddr_t, vm_size_t, vm_prot_t, vm_offset_t);
4c45483e GW	86	void swap_pager_dealloc(vm_pager_t);
	87	boolean_t swap_pager_getpage(vm_pager_t, vm_page_t, boolean_t);
	88	boolean_t swap_pager_putpage(vm_pager_t, vm_page_t, boolean_t);
736d20f2	89	boolean_t swap_pager_getmulti(vm_pager_t, vm_page_t *, int, int, boolean_t);
4c45483e	90	boolean_t swap_pager_haspage(vm_pager_t, vm_offset_t);
736d20f2	91	int swap_pager_io(sw_pager_t, vm_page_t *, int, int, int);
4c45483e	92	void swap_pager_iodone(struct buf *);
22c84afa	93	boolean_t swap_pager_clean();
15637ed4	94
bbc3f849	95	extern struct pagerops swappagerops;
15637ed4	96
15637ed4 RG	97	#endif
	98
	99	#endif /* _SWAP_PAGER_ */