Return to vnode_pager.h CVS log

Up to [Apple Darwin 0.x] / kernel / vm

Annotation of kernel/vm/vnode_pager.h, revision 1.1

1.1     ! root        1: /*
        !             2:  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
        !             3:  *
        !             4:  * @APPLE_LICENSE_HEADER_START@
        !             5:  * 
        !             6:  * Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
        !             7:  * Reserved.  This file contains Original Code and/or Modifications of
        !             8:  * Original Code as defined in and that are subject to the Apple Public
        !             9:  * Source License Version 1.1 (the "License").  You may not use this file
        !            10:  * except in compliance with the License.  Please obtain a copy of the
        !            11:  * License at http://www.apple.com/publicsource and read it before using
        !            12:  * this file.
        !            13:  * 
        !            14:  * The Original Code and all software distributed under the License are
        !            15:  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
        !            16:  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
        !            17:  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
        !            18:  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
        !            19:  * License for the specific language governing rights and limitations
        !            20:  * under the License.
        !            21:  * 
        !            22:  * @APPLE_LICENSE_HEADER_END@
        !            23:  */
        !            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: #ifndef        _VNODE_PAGER_
        !            33: #define        _VNODE_PAGER_   1
        !            34: 
        !            35: #import <mach/kern_return.h>
        !            36: #import <sys/types.h>
        !            37: #import <kern/lock.h>
        !            38: #import <kern/queue.h>
        !            39: 
        !            40: kern_return_t  mach_swapon();
        !            41: 
        !            42: #ifdef KERNEL
        !            43: 
        !            44: #import <mach/boolean.h>
        !            45: #import <vm/vm_pager.h>
        !            46: 
        !            47: void           vnode_pager_init();
        !            48: 
        !            49: vm_pager_t     vnode_pager_setup();
        !            50: boolean_t      vnode_has_page();
        !            51: boolean_t      vnode_pager_active();
        !            52: 
        !            53: /*
        !            54:  *  Vstructs are the internal (to us) description of a unit of backing store.
        !            55:  *  The are the link between memory objects and the backing store they represent.
        !            56:  *  For the vnode pager, backing store comes in two flavors: normal files and
        !            57:  *  swap files.
        !            58:  *
        !            59:  *  For objects that page to and from normal files (e.g. objects that represent
        !            60:  *  program text segments), we maintain some simple parameters that allow us to
        !            61:  *  access the file's contents directly through the vnode interface.
        !            62:  *
        !            63:  *  Data for objects without associated vnodes is maintained in the swap files.
        !            64:  *  Each object that uses one of these as backing store has a vstruct indicating
        !            65:  *  the swap file of preference (vs_pf) and a mapping between contiguous object
        !            66:  *  offsets and swap file offsets (vs_pmap).  Each entry in this mapping specifies
        !            67:  *  the pager file to use, and the offset of the page in that pager file.  These
        !            68:  *  mapping entries are of type pfMapEntry.
        !            69:  */
        !            70: 
        !            71: /*
        !            72:  * Pager file structure.  One per swap file.
        !            73:  */
        !            74: typedef struct pager_file {
        !            75:        queue_chain_t   pf_chain;       /* link to other paging files */
        !            76:        struct  vnode   *pf_vp;         /* vnode of paging file */
        !            77:        u_int           pf_count;       /* Number of vstruct using this file */
        !            78:        u_char          *pf_bmap;       /* Map of used blocks */
        !            79:        long            pf_npgs;        /* Size of file in pages */
        !            80:        long            pf_pfree;       /* Number of unused pages */
        !            81:        long            pf_lowat;       /* Low water page */
        !            82:        long            pf_hipage;      /* Highest page allocated */
        !            83:        long            pf_hint;        /* Lowest page unallocated */
        !            84:        char            *pf_name;       /* Filename of this file */
        !            85:        boolean_t       pf_prefer;
        !            86:        int             pf_index;       /* index into the pager_file array */
        !            87:        lock_data_t     pf_lock;        /* Lock for alloc and dealloc */
        !            88: } *pager_file_t;
        !            89: 
        !            90: #define        PAGER_FILE_NULL (pager_file_t) 0
        !            91: 
        !            92: #define        MAXPAGERFILES 16
        !            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 vnode_pagein();
        !           128: pager_return_t vnode_pageout();
        !           129: void           vnode_dealloc();
        !           130: vm_pager_t     vnode_alloc();
        !           131: int            vnode_uncache();
        !           132: 
        !           133: #endif /* KERNEL */
        !           134: 
        !           135: #endif /* _VNODE_PAGER_ */

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.