bsd/vm/vm_pager.h

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  * Mach Operating System
  27  * Copyright (c) 1987 Carnegie-Mellon University
  28  * All rights reserved.  The CMU software License Agreement specifies
  29  * the terms and conditions for use and redistribution.
  30  */
  31 /*
  32  *      File:   vm_pager.h
  33  *      Author: Avadis Tevanian, Jr., Michael Wayne Young
  34  *
  35  *      Copyright (C) 1986, Avadis Tevanian, Jr., Michael Wayne Young
  36  *      Copyright (C) 1985, Avadis Tevanian, Jr., Michael Wayne Young
  37  *
  38  *      Pager routine interface definition
  39  */
  40
  41 #ifndef _VM_PAGER_
  42 #define _VM_PAGER_
  43
  44 #include <mach/boolean.h>
  45
  46 struct  pager_struct {
  47         boolean_t       is_device;
  48 };
  49 typedef struct pager_struct     *vm_pager_t;
  50 #define vm_pager_null           ((vm_pager_t) 0)
  51
  52 #define PAGER_SUCCESS           0  /* page read or written */
  53 #define PAGER_ABSENT            1  /* pager does not have page */
  54 #define PAGER_ERROR             2  /* pager unable to read or write page */
  55
  56 #ifdef  KERNEL
  57 typedef int             pager_return_t;
  58
  59 vm_pager_t      vm_pager_allocate();
  60 void            vm_pager_deallocate();
  61 pager_return_t  vm_pager_get();
  62 pager_return_t  vm_pager_put();
  63 boolean_t       vm_pager_has_page();
  64 #endif  /* KERNEL */
  65
  66 #endif  /* _VM_PAGER_ */