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/*
* Copyright (c) 1990 University of Utah.
* Copyright (c) 1991, 1993
* 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 8.4 (Berkeley) 1/12/94
* $FreeBSD$
*/
/*
* Pager routine interface definition.
*/
#ifndef _VM_PAGER_
#define _VM_PAGER_
#include <sys/queue.h>
TAILQ_HEAD(pagerlst, vm_object);
struct bio;
struct pagerops {
void (*pgo_init)(void); /* Initialize pager. */
vm_object_t (*pgo_alloc)(void *, vm_ooffset_t, vm_prot_t, vm_ooffset_t); /* Allocate pager. */
void (*pgo_dealloc)(vm_object_t); /* Disassociate. */
int (*pgo_getpages)(vm_object_t, vm_page_t *, int, int); /* Get (read) page. */
void (*pgo_putpages)(vm_object_t, vm_page_t *, int, int, int *); /* Put (write) page. */
boolean_t (*pgo_haspage)(vm_object_t, vm_pindex_t, int *, int *); /* Does pager have page? */
void (*pgo_pageunswapped)(vm_page_t);
void (*pgo_strategy)(vm_object_t, struct bio *);
};
/*
* 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
* ERROR error while accessing data that is in range and exists
* AGAIN temporary resource shortage prevented operation from happening
*/
#define VM_PAGER_OK 0
#define VM_PAGER_BAD 1
#define VM_PAGER_FAIL 2
#define VM_PAGER_PEND 3
#define VM_PAGER_ERROR 4
#define VM_PAGER_AGAIN 5
#define VM_PAGER_PUT_SYNC 0x1
#define VM_PAGER_PUT_INVAL 0x2
#ifdef _KERNEL
#ifdef MALLOC_DECLARE
MALLOC_DECLARE(M_VMPGDATA);
#endif
extern vm_map_t pager_map;
extern int pager_map_size;
extern struct pagerops *pagertab[];
extern struct mtx pbuf_mtx;
vm_object_t vm_pager_allocate(objtype_t, void *, vm_ooffset_t, vm_prot_t, vm_ooffset_t);
void vm_pager_bufferinit(void);
void vm_pager_deallocate(vm_object_t);
static __inline int vm_pager_get_pages(vm_object_t, vm_page_t *, int, int);
static __inline boolean_t vm_pager_has_page(vm_object_t, vm_pindex_t, int *, int *);
void vm_pager_init(void);
vm_object_t vm_pager_object_lookup(struct pagerlst *, void *);
vm_offset_t vm_pager_map_pages(vm_page_t *, int, boolean_t);
vm_offset_t vm_pager_map_page(vm_page_t);
void vm_pager_sync(void);
void vm_pager_unmap_pages(vm_offset_t, int);
void vm_pager_unmap_page(vm_offset_t);
void vm_pager_strategy(vm_object_t object, struct bio *bp);
/*
* vm_page_get_pages:
*
* Retrieve pages from the VM system in order to map them into an object
* ( or into VM space somewhere ). If the pagein was successful, we
* must fully validate it.
*/
static __inline int
vm_pager_get_pages(
vm_object_t object,
vm_page_t *m,
int count,
int reqpage
) {
int r;
GIANT_REQUIRED;
r = (*pagertab[object->type]->pgo_getpages)(object, m, count, reqpage);
if (r == VM_PAGER_OK && m[reqpage]->valid != VM_PAGE_BITS_ALL) {
vm_page_zero_invalid(m[reqpage], TRUE);
}
return (r);
}
static __inline void
vm_pager_put_pages(
vm_object_t object,
vm_page_t *m,
int count,
int flags,
int *rtvals
) {
GIANT_REQUIRED;
(*pagertab[object->type]->pgo_putpages)
(object, m, count, flags, rtvals);
}
/*
* vm_pager_haspage
*
* Check to see if an object's pager has the requested page. The
* object's pager will also set before and after to give the caller
* some idea of the number of pages before and after the requested
* page can be I/O'd efficiently.
*
* This routine does not have to be called at any particular spl.
*/
static __inline boolean_t
vm_pager_has_page(
vm_object_t object,
vm_pindex_t offset,
int *before,
int *after
) {
boolean_t ret;
GIANT_REQUIRED;
ret = (*pagertab[object->type]->pgo_haspage)
(object, offset, before, after);
return (ret);
}
/*
* vm_pager_page_unswapped
*
* called at splvm() to destroy swap associated with the page.
*
* This function may not block.
*/
static __inline void
vm_pager_page_unswapped(vm_page_t m)
{
GIANT_REQUIRED;
if (pagertab[m->object->type]->pgo_pageunswapped)
(*pagertab[m->object->type]->pgo_pageunswapped)(m);
}
#endif /* _KERNEL */
#endif /* _VM_PAGER_ */
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