[apple/xnu.git] / bsd / vm / vnode_pager.h

/*
 * Copyright (c) 2000-2004 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 <mach/memory_object_types.h>
#include <mach/vm_types.h>
#include <vm/vm_pager.h>

vm_pager_t	vnode_pager_setup(struct vnode *, memory_object_t);

/*
 *  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;
};
extern struct bs_map  bs_port_table[];


/*
 * 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	vnode_pagein(struct vnode *, upl_t,
			     upl_offset_t, vm_object_offset_t,
			     upl_size_t, int, int *);
pager_return_t	vnode_pageout(struct vnode *, upl_t,
			      upl_offset_t, vm_object_offset_t,
			      upl_size_t, int, int *);

extern vm_object_offset_t vnode_pager_get_filesize(
	struct vnode *vp);

extern kern_return_t vnode_pager_get_pathname(
	struct vnode	*vp,
	char		*pathname,
	vm_size_t	*length_p);

extern kern_return_t vnode_pager_get_filename(
	struct vnode	*vp,
	char		**filename);

#endif	/* KERNEL */

#endif	/* _VNODE_PAGER_ */
Commit	Line	Data
1c79356b	1	/*
91447636	2	* Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
1c79356b A	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
37839358 A	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.
1c79356b	11	*
37839358 A	12	* This Original Code and all software distributed under the License are
37839358 A	13	* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
1c79356b A	14	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
1c79356b A	15	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
37839358 A	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.
1c79356b A	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
1c79356b	37	#include <mach/boolean.h>
91447636 A	38	#include <mach/memory_object_types.h>
91447636 A	39	#include <mach/vm_types.h>
1c79356b A	40	#include <vm/vm_pager.h>
1c79356b A	41
91447636	42	vm_pager_t vnode_pager_setup(struct vnode *, memory_object_t);
1c79356b A	43
	44	/*
	45	* Vstructs are the internal (to us) description of a unit of backing store.
	46	* The are the link between memory objects and the backing store they represent.
	47	* For the vnode pager, backing store comes in two flavors: normal files and
	48	* swap files.
	49	*
	50	* For objects that page to and from normal files (e.g. objects that represent
	51	* program text segments), we maintain some simple parameters that allow us to
	52	* access the file's contents directly through the vnode interface.
	53	*
	54	* Data for objects without associated vnodes is maintained in the swap files.
	55	* Each object that uses one of these as backing store has a vstruct indicating
	56	* the swap file of preference (vs_pf) and a mapping between contiguous object
	57	* offsets and swap file offsets (vs_pmap). Each entry in this mapping specifies
	58	* the pager file to use, and the offset of the page in that pager file. These
	59	* mapping entries are of type pfMapEntry.
	60	*/
	61
	62	/*
	63	* Pager file structure. One per swap file.
	64	*/
	65	typedef struct pager_file {
	66	queue_chain_t pf_chain; /* link to other paging files */
	67	struct vnode pf_vp; / vnode of paging file */
	68	u_int pf_count; /* Number of vstruct using this file */
	69	u_char pf_bmap; / Map of used blocks */
	70	long pf_npgs; /* Size of file in pages */
	71	long pf_pfree; /* Number of unused pages */
	72	long pf_lowat; /* Low water page */
	73	long pf_hipage; /* Highest page allocated */
	74	long pf_hint; /* Lowest page unallocated */
	75	char pf_name; / Filename of this file */
	76	boolean_t pf_prefer;
	77	int pf_index; /* index into the pager_file array */
	78	void * pf_lock; /* Lock for alloc and dealloc */
	79	} *pager_file_t;
	80
	81	#define PAGER_FILE_NULL (pager_file_t) 0
	82
	83	#define MAXPAGERFILES 16
	84
	85	#define MAX_BACKING_STORE 100
	86
	87	struct bs_map {
	88	struct vnode *vp;
	89	void *bs;
	90	};
91447636	91	extern struct bs_map bs_port_table[];
1c79356b A	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
91447636 A	126	pager_return_t vnode_pagein(struct vnode *, upl_t,
	127	upl_offset_t, vm_object_offset_t,
	128	upl_size_t, int, int *);
	129	pager_return_t vnode_pageout(struct vnode *, upl_t,
	130	upl_offset_t, vm_object_offset_t,
	131	upl_size_t, int, int *);
1c79356b	132
91447636 A	133	extern vm_object_offset_t vnode_pager_get_filesize(
91447636 A	134	struct vnode *vp);
1c79356b	135
c0fea474 A	136	extern kern_return_t vnode_pager_get_pathname(
	137	struct vnode *vp,
	138	char *pathname,
	139	vm_size_t *length_p);
	140
	141	extern kern_return_t vnode_pager_get_filename(
	142	struct vnode *vp,
	143	char **filename);
	144
1c79356b A	145	#endif /* KERNEL */
	146
	147	#endif /* _VNODE_PAGER_ */