projects / apple / xnu.git / blame
| Commit | Line | Data |
|---|---|---|
| 1c79356b A |
1 | /* |
| 2 | * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. | |
| 3 | * | |
| 4 | * @APPLE_LICENSE_HEADER_START@ | |
| 5 | * | |
| 6 | * The contents of this file constitute Original Code as defined in and | |
| 7 | * are subject to the Apple Public Source License Version 1.1 (the | |
| 8 | * "License"). You may not use this file except in compliance with the | |
| 9 | * License. Please obtain a copy of the License at | |
| 10 | * http://www.apple.com/publicsource and read it before using this file. | |
| 11 | * | |
| 12 | * This Original Code and all software distributed under the License are | |
| 13 | * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER | |
| 14 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, | |
| 15 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, | |
| 16 | * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the | |
| 17 | * License for the specific language governing rights and limitations | |
| 18 | * under the License. | |
| 19 | * | |
| 20 | * @APPLE_LICENSE_HEADER_END@ | |
| 21 | */ | |
| 22 | /* | |
| 23 | * Mach Operating System | |
| 24 | * Copyright (c) 1987 Carnegie-Mellon University | |
| 25 | * All rights reserved. The CMU software License Agreement specifies | |
| 26 | * the terms and conditions for use and redistribution. | |
| 27 | */ | |
| 28 | ||
| 29 | #ifndef _VNODE_PAGER_ | |
| 30 | #define _VNODE_PAGER_ 1 | |
| 31 | ||
| 32 | #include <mach/kern_return.h> | |
| 33 | #include <sys/types.h> | |
| 34 | #include <kern/queue.h> | |
| 35 | ||
| 36 | #ifdef KERNEL | |
| 37 | ||
| 38 | #include <mach/boolean.h> | |
| 39 | #include <vm/vm_pager.h> | |
| 40 | ||
| 1c79356b A |
41 | vm_pager_t vnode_pager_setup(); |
| 42 | boolean_t vnode_has_page(); | |
| 43 | boolean_t vnode_pager_active(); | |
| 44 | ||
| 45 | /* | |
| 46 | * Vstructs are the internal (to us) description of a unit of backing store. | |
| 47 | * The are the link between memory objects and the backing store they represent. | |
| 48 | * For the vnode pager, backing store comes in two flavors: normal files and | |
| 49 | * swap files. | |
| 50 | * | |
| 51 | * For objects that page to and from normal files (e.g. objects that represent | |
| 52 | * program text segments), we maintain some simple parameters that allow us to | |
| 53 | * access the file's contents directly through the vnode interface. | |
| 54 | * | |
| 55 | * Data for objects without associated vnodes is maintained in the swap files. | |
| 56 | * Each object that uses one of these as backing store has a vstruct indicating | |
| 57 | * the swap file of preference (vs_pf) and a mapping between contiguous object | |
| 58 | * offsets and swap file offsets (vs_pmap). Each entry in this mapping specifies | |
| 59 | * the pager file to use, and the offset of the page in that pager file. These | |
| 60 | * mapping entries are of type pfMapEntry. | |
| 61 | */ | |
| 62 | ||
| 63 | /* | |
| 64 | * Pager file structure. One per swap file. | |
| 65 | */ | |
| 66 | typedef struct pager_file { | |
| 67 | queue_chain_t pf_chain; /* link to other paging files */ | |
| 68 | struct vnode *pf_vp; /* vnode of paging file */ | |
| 69 | u_int pf_count; /* Number of vstruct using this file */ | |
| 70 | u_char *pf_bmap; /* Map of used blocks */ | |
| 71 | long pf_npgs; /* Size of file in pages */ | |
| 72 | long pf_pfree; /* Number of unused pages */ | |
| 73 | long pf_lowat; /* Low water page */ | |
| 74 | long pf_hipage; /* Highest page allocated */ | |
| 75 | long pf_hint; /* Lowest page unallocated */ | |
| 76 | char *pf_name; /* Filename of this file */ | |
| 77 | boolean_t pf_prefer; | |
| 78 | int pf_index; /* index into the pager_file array */ | |
| 79 | void * pf_lock; /* Lock for alloc and dealloc */ | |
| 80 | } *pager_file_t; | |
| 81 | ||
| 82 | #define PAGER_FILE_NULL (pager_file_t) 0 | |
| 83 | ||
| 84 | #define MAXPAGERFILES 16 | |
| 85 | ||
| 86 | #define MAX_BACKING_STORE 100 | |
| 87 | ||
| 88 | struct bs_map { | |
| 89 | struct vnode *vp; | |
| 90 | void *bs; | |
| 91 | }; | |
| 92 | ||
| 93 | ||
| 94 | ||
| 95 | /* | |
| 96 | * Pager file data structures. | |
| 97 | */ | |
| 98 | #define INDEX_NULL 0 | |
| 99 | typedef struct { | |
| 100 | unsigned int index:8; /* paging file this block is in */ | |
| 101 | unsigned int offset:24; /* page number where block resides */ | |
| 102 | } pf_entry; | |
| 103 | ||
| 104 | typedef enum { | |
| 105 | IS_INODE, /* Local disk */ | |
| 106 | IS_RNODE /* NFS */ | |
| 107 | } vpager_fstype; | |
| 108 | ||
| 109 | /* | |
| 110 | * Basic vnode pager structure. One per object, backing-store pair. | |
| 111 | */ | |
| 112 | typedef struct vstruct { | |
| 113 | boolean_t is_device; /* Must be first - see vm_pager.h */ | |
| 114 | pager_file_t vs_pf; /* Pager file this uses */ | |
| 115 | pf_entry **vs_pmap; /* Map of pages into paging file */ | |
| 116 | unsigned int | |
| 117 | /* boolean_t */ vs_swapfile:1; /* vnode is a swapfile */ | |
| 118 | short vs_count; /* use count */ | |
| 119 | int vs_size; /* size of this chunk in pages*/ | |
| 120 | struct vnode *vs_vp; /* vnode to page to */ | |
| 121 | } *vnode_pager_t; | |
| 122 | ||
| 123 | #define VNODE_PAGER_NULL ((vnode_pager_t) 0) | |
| 124 | ||
| 125 | ||
| 126 | ||
| 127 | pager_return_t pager_vnode_pagein(); | |
| 128 | pager_return_t pager_vnode_pageout(); | |
| 129 | pager_return_t vnode_pagein(); | |
| 130 | pager_return_t vnode_pageout(); | |
| 131 | ||
| 132 | #endif /* KERNEL */ | |
| 133 | ||
| 134 | #endif /* _VNODE_PAGER_ */ |