NetBSD/sys/vm/vm_pager.h

107 lines
3.9 KiB
C

/*
* 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.
*
* @(#)vm_pager.h 7.2 (Berkeley) 4/20/91
*/
#ifndef _VM_VM_PAGER_H_
#define _VM_VM_PAGER_H_
/*
* Pager routine interface definition.
* For BSD we use a cleaner version of the internal pager interface.
*/
struct pager_struct {
queue_head_t pg_list; /* links for list management */
caddr_t pg_handle; /* external handle (vp, dev, fp) */
int pg_type; /* type of pager */
struct pagerops *pg_ops; /* pager operations */
caddr_t pg_data; /* private pager data */
};
typedef struct pager_struct *vm_pager_t;
/* pager types */
#define PG_DFLT -1
#define PG_SWAP 0
#define PG_VNODE 1
#define PG_DEVICE 2
struct pagerops {
void (*pgo_init)(); /* initialize pager */
vm_pager_t (*pgo_alloc)(); /* allocate pager */
void (*pgo_dealloc)(); /* disassociate */
int (*pgo_getpage)(); /* get (read) page */
int (*pgo_putpage)(); /* put (write) page */
boolean_t (*pgo_haspage)(); /* does pager have page? */
};
/*
* get/put return values
* OK operation was successful
* BAD specified data was out of the accepted range
* FAIL specified data was in range, but doesn't exist
* PEND operations was initiated but not completed
*/
#define VM_PAGER_OK 0
#define VM_PAGER_BAD 1
#define VM_PAGER_FAIL 2
#define VM_PAGER_PEND 3
#define VM_PAGER_ALLOC(h, s, p) (*(pg)->pg_ops->pgo_alloc)(h, s, p)
#define VM_PAGER_DEALLOC(pg) (*(pg)->pg_ops->pgo_dealloc)(pg)
#define VM_PAGER_GET(pg, m, s) (*(pg)->pg_ops->pgo_getpage)(pg, m, s)
#define VM_PAGER_PUT(pg, m, s) (*(pg)->pg_ops->pgo_putpage)(pg, m, s)
#define VM_PAGER_HASPAGE(pg, o) (*(pg)->pg_ops->pgo_haspage)(pg, o)
#ifdef KERNEL
vm_pager_t vm_pager_allocate();
void vm_pager_deallocate();
int vm_pager_get();
int vm_pager_put();
boolean_t vm_pager_has_page();
vm_offset_t vm_pager_map_page();
void vm_pager_unmap_page();
vm_pager_t vm_pager_lookup();
void vm_pager_sync();
extern struct pagerops *dfltpagerops;
#endif
#endif /* !_VM_VM_PAGER_H_ */