xref: /freebsd/sys/vm/swap_pager.h (revision e9ac41698b2f322d55ccf9da50a3596edb2c1800)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1990 University of Utah.
5  * Copyright (c) 1991 The Regents of the University of California.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * the Systems Programming Group of the University of Utah Computer
10  * Science Department.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef	_VM_SWAP_PAGER_H_
38 #define	_VM_SWAP_PAGER_H_
39 
40 #include <sys/_types.h>
41 
42 struct buf;
43 struct swdevt;
44 struct thread;
45 typedef void sw_strategy_t(struct buf *, struct swdevt *);
46 typedef void sw_close_t(struct thread *, struct swdevt *);
47 
48 /*
49  * Swap device table
50  */
51 struct swdevt {
52 	int	sw_flags;
53 	int	sw_nblks;
54 	int     sw_used;
55 	dev_t	sw_dev;
56 	struct vnode *sw_vp;
57 	void	*sw_id;
58 	__daddr_t sw_first;
59 	__daddr_t sw_end;
60 	struct blist *sw_blist;
61 	TAILQ_ENTRY(swdevt)	sw_list;
62 	sw_strategy_t		*sw_strategy;
63 	sw_close_t		*sw_close;
64 };
65 
66 #define	SW_UNMAPPED	0x01
67 #define	SW_CLOSING	0x04
68 
69 #ifdef _KERNEL
70 
71 extern int swap_pager_avail;
72 extern int nsw_cluster_max;
73 
74 struct xswdev;
75 int swap_dev_info(int name, struct xswdev *xs, char *devname, size_t len);
76 void swap_pager_copy(vm_object_t, vm_object_t, vm_pindex_t, int);
77 vm_pindex_t swap_pager_find_least(vm_object_t object, vm_pindex_t pindex);
78 void swap_pager_freespace(vm_object_t object, vm_pindex_t start,
79     vm_size_t size, vm_size_t *freed);
80 void swap_pager_swap_init(void);
81 int swap_pager_nswapdev(void);
82 int swap_pager_reserve(vm_object_t, vm_pindex_t, vm_pindex_t);
83 void swap_pager_status(int *total, int *used);
84 u_long swap_pager_swapped_pages(vm_object_t object);
85 void swapoff_all(void);
86 bool swap_pager_init_object(vm_object_t object, void *handle,
87     struct ucred *cred, vm_ooffset_t size, vm_ooffset_t offset);
88 #endif				/* _KERNEL */
89 #endif				/* _VM_SWAP_PAGER_H_ */
90