swap_pager.h revision 331722 
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 * 4. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 *	from: @(#)swap_pager.h	7.1 (Berkeley) 12/5/90
35 * $FreeBSD: stable/11/sys/vm/swap_pager.h 331722 2018-03-29 02:50:57Z eadler $
36 */
37
38#ifndef	_VM_SWAP_PAGER_H_
39#define	_VM_SWAP_PAGER_H_ 1
40
41typedef	int32_t	swblk_t;	/*
42				 * swap offset.  This is the type used to
43				 * address the "virtual swap device" and
44				 * therefore the maximum swap space is
45				 * 2^32 pages.
46				 */
47
48struct buf;
49struct swdevt;
50typedef void sw_strategy_t(struct buf *, struct swdevt *);
51typedef void sw_close_t(struct thread *, struct swdevt *);
52
53/*
54 * Swap device table
55 */
56struct swdevt {
57	int	sw_flags;
58	int	sw_nblks;
59	int     sw_used;
60	dev_t	sw_dev;
61	struct vnode *sw_vp;
62	void	*sw_id;
63	swblk_t	sw_first;
64	swblk_t	sw_end;
65	struct blist *sw_blist;
66	TAILQ_ENTRY(swdevt)	sw_list;
67	sw_strategy_t		*sw_strategy;
68	sw_close_t		*sw_close;
69};
70
71#define	SW_UNMAPPED	0x01
72#define	SW_CLOSING	0x04
73
74#ifdef _KERNEL
75
76extern int swap_pager_avail;
77
78struct xswdev;
79int swap_dev_info(int name, struct xswdev *xs, char *devname, size_t len);
80void swap_pager_copy(vm_object_t, vm_object_t, vm_pindex_t, int);
81vm_pindex_t swap_pager_find_least(vm_object_t object, vm_pindex_t pindex);
82void swap_pager_freespace(vm_object_t, vm_pindex_t, vm_size_t);
83void swap_pager_swap_init(void);
84int swap_pager_reserve(vm_object_t, vm_pindex_t, vm_size_t);
85void swap_pager_status(int *total, int *used);
86void swapoff_all(void);
87
88#endif				/* _KERNEL */
89#endif				/* _VM_SWAP_PAGER_H_ */
90