/* * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * The contents of this file constitute Original Code as defined in and * are subject to the Apple Public Source License Version 1.1 (the * "License"). You may not use this file except in compliance with the * License. Please obtain a copy of the License at * http://www.apple.com/publicsource and read it before using this file. * * This Original Code and all software distributed under the License are * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the * License for the specific language governing rights and limitations * under the License. * * @APPLE_LICENSE_HEADER_END@ */ /* * Mach Operating System * Copyright (c) 1987 Carnegie-Mellon University * All rights reserved. The CMU software License Agreement specifies * the terms and conditions for use and redistribution. */ #ifndef _VNODE_PAGER_ #define _VNODE_PAGER_ 1 #include <mach/kern_return.h> #include <sys/types.h> #include <kern/queue.h> #ifdef KERNEL #include <mach/boolean.h> #include <vm/vm_pager.h> vm_pager_t vnode_pager_setup(); boolean_t vnode_has_page(); boolean_t vnode_pager_active(); /* * Vstructs are the internal (to us) description of a unit of backing store. * The are the link between memory objects and the backing store they represent. * For the vnode pager, backing store comes in two flavors: normal files and * swap files. * * For objects that page to and from normal files (e.g. objects that represent * program text segments), we maintain some simple parameters that allow us to * access the file's contents directly through the vnode interface. * * Data for objects without associated vnodes is maintained in the swap files. * Each object that uses one of these as backing store has a vstruct indicating * the swap file of preference (vs_pf) and a mapping between contiguous object * offsets and swap file offsets (vs_pmap). Each entry in this mapping specifies * the pager file to use, and the offset of the page in that pager file. These * mapping entries are of type pfMapEntry. */ /* * Pager file structure. One per swap file. */ typedef struct pager_file { queue_chain_t pf_chain; /* link to other paging files */ struct vnode *pf_vp; /* vnode of paging file */ u_int pf_count; /* Number of vstruct using this file */ u_char *pf_bmap; /* Map of used blocks */ long pf_npgs; /* Size of file in pages */ long pf_pfree; /* Number of unused pages */ long pf_lowat; /* Low water page */ long pf_hipage; /* Highest page allocated */ long pf_hint; /* Lowest page unallocated */ char *pf_name; /* Filename of this file */ boolean_t pf_prefer; int pf_index; /* index into the pager_file array */ void * pf_lock; /* Lock for alloc and dealloc */ } *pager_file_t; #define PAGER_FILE_NULL (pager_file_t) 0 #define MAXPAGERFILES 16 #define MAX_BACKING_STORE 100 struct bs_map { struct vnode *vp; void *bs; }; /* * Pager file data structures. */ #define INDEX_NULL 0 typedef struct { unsigned int index:8; /* paging file this block is in */ unsigned int offset:24; /* page number where block resides */ } pf_entry; typedef enum { IS_INODE, /* Local disk */ IS_RNODE /* NFS */ } vpager_fstype; /* * Basic vnode pager structure. One per object, backing-store pair. */ typedef struct vstruct { boolean_t is_device; /* Must be first - see vm_pager.h */ pager_file_t vs_pf; /* Pager file this uses */ pf_entry **vs_pmap; /* Map of pages into paging file */ unsigned int /* boolean_t */ vs_swapfile:1; /* vnode is a swapfile */ short vs_count; /* use count */ int vs_size; /* size of this chunk in pages*/ struct vnode *vs_vp; /* vnode to page to */ } *vnode_pager_t; #define VNODE_PAGER_NULL ((vnode_pager_t) 0) pager_return_t pager_vnode_pagein(); pager_return_t pager_vnode_pageout(); pager_return_t vnode_pagein(); pager_return_t vnode_pageout(); #endif /* KERNEL */ #endif /* _VNODE_PAGER_ */