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

/*
 * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code 
 * as defined in and that are subject to the Apple Public Source License 
 * Version 2.0 (the 'License'). You may not use this file except in 
 * compliance with the License.  The rights granted to you under the 
 * License may not be used to create, or enable the creation or 
 * redistribution of, unlawful or unlicensed copies of an Apple operating 
 * system, or to circumvent, violate, or enable the circumvention or 
 * violation of, any terms of an Apple operating system software license 
 * agreement.
 *
 * Please obtain a copy of the License at 
 * http://www.opensource.apple.com/apsl/ and read it before using this 
 * file.
 *
 * The 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, QUIET ENJOYMENT OR NON-INFRINGEMENT. 
 * Please see the License for the specific language governing rights and 
 * limitations under the License.
 *
 * @APPLE_LICENSE_OSREFERENCE_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	/*
5d5c5d0d A	2	* Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
5d5c5d0d A	3	*
8ad349bb	4	* @APPLE_LICENSE_OSREFERENCE_HEADER_START@
1c79356b	5	*
8ad349bb A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the
	10	* License may not be used to create, or enable the creation or
	11	* redistribution of, unlawful or unlicensed copies of an Apple operating
	12	* system, or to circumvent, violate, or enable the circumvention or
	13	* violation of, any terms of an Apple operating system software license
	14	* agreement.
	15	*
	16	* Please obtain a copy of the License at
	17	* http://www.opensource.apple.com/apsl/ and read it before using this
	18	* file.
	19	*
	20	* The Original Code and all software distributed under the License are
	21	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	22	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	23	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	24	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	25	* Please see the License for the specific language governing rights and
	26	* limitations under the License.
	27	*
	28	* @APPLE_LICENSE_OSREFERENCE_HEADER_END@
1c79356b A	29	*/
	30	/*
	31	* Mach Operating System
	32	* Copyright (c) 1987 Carnegie-Mellon University
	33	* All rights reserved. The CMU software License Agreement specifies
	34	* the terms and conditions for use and redistribution.
	35	*/
	36
	37	#ifndef _VNODE_PAGER_
	38	#define _VNODE_PAGER_ 1
	39
	40	#include <mach/kern_return.h>
	41	#include <sys/types.h>
	42	#include <kern/queue.h>
	43
	44	#ifdef KERNEL
1c79356b	45	#include <mach/boolean.h>
91447636 A	46	#include <mach/memory_object_types.h>
91447636 A	47	#include <mach/vm_types.h>
1c79356b A	48	#include <vm/vm_pager.h>
1c79356b A	49
91447636	50	vm_pager_t vnode_pager_setup(struct vnode *, memory_object_t);
1c79356b A	51
	52	/*
	53	* Vstructs are the internal (to us) description of a unit of backing store.
	54	* The are the link between memory objects and the backing store they represent.
	55	* For the vnode pager, backing store comes in two flavors: normal files and
	56	* swap files.
	57	*
	58	* For objects that page to and from normal files (e.g. objects that represent
	59	* program text segments), we maintain some simple parameters that allow us to
	60	* access the file's contents directly through the vnode interface.
	61	*
	62	* Data for objects without associated vnodes is maintained in the swap files.
	63	* Each object that uses one of these as backing store has a vstruct indicating
	64	* the swap file of preference (vs_pf) and a mapping between contiguous object
	65	* offsets and swap file offsets (vs_pmap). Each entry in this mapping specifies
	66	* the pager file to use, and the offset of the page in that pager file. These
	67	* mapping entries are of type pfMapEntry.
	68	*/
	69
	70	/*
	71	* Pager file structure. One per swap file.
	72	*/
	73	typedef struct pager_file {
	74	queue_chain_t pf_chain; /* link to other paging files */
	75	struct vnode pf_vp; / vnode of paging file */
	76	u_int pf_count; /* Number of vstruct using this file */
	77	u_char pf_bmap; / Map of used blocks */
	78	long pf_npgs; /* Size of file in pages */
	79	long pf_pfree; /* Number of unused pages */
	80	long pf_lowat; /* Low water page */
	81	long pf_hipage; /* Highest page allocated */
	82	long pf_hint; /* Lowest page unallocated */
	83	char pf_name; / Filename of this file */
	84	boolean_t pf_prefer;
	85	int pf_index; /* index into the pager_file array */
	86	void * pf_lock; /* Lock for alloc and dealloc */
	87	} *pager_file_t;
	88
	89	#define PAGER_FILE_NULL (pager_file_t) 0
	90
	91	#define MAXPAGERFILES 16
	92
	93	#define MAX_BACKING_STORE 100
	94
	95	struct bs_map {
	96	struct vnode *vp;
	97	void *bs;
	98	};
91447636	99	extern struct bs_map bs_port_table[];
1c79356b A	100
	101
	102
	103	/*
	104	* Pager file data structures.
	105	*/
	106	#define INDEX_NULL 0
	107	typedef struct {
	108	unsigned int index:8; /* paging file this block is in */
	109	unsigned int offset:24; /* page number where block resides */
	110	} pf_entry;
	111
	112	typedef enum {
	113	IS_INODE, /* Local disk */
	114	IS_RNODE /* NFS */
	115	} vpager_fstype;
	116
	117	/*
	118	* Basic vnode pager structure. One per object, backing-store pair.
	119	*/
	120	typedef struct vstruct {
	121	boolean_t is_device; /* Must be first - see vm_pager.h */
	122	pager_file_t vs_pf; /* Pager file this uses */
	123	pf_entry *vs_pmap; / Map of pages into paging file */
	124	unsigned int
	125	/* boolean_t / vs_swapfile:1; / vnode is a swapfile */
	126	short vs_count; /* use count */
	127	int vs_size; /* size of this chunk in pages*/
	128	struct vnode vs_vp; / vnode to page to */
	129	} *vnode_pager_t;
	130
	131	#define VNODE_PAGER_NULL ((vnode_pager_t) 0)
	132
	133
91447636 A	134	pager_return_t vnode_pagein(struct vnode *, upl_t,
	135	upl_offset_t, vm_object_offset_t,
	136	upl_size_t, int, int *);
	137	pager_return_t vnode_pageout(struct vnode *, upl_t,
	138	upl_offset_t, vm_object_offset_t,
	139	upl_size_t, int, int *);
1c79356b	140
91447636 A	141	extern vm_object_offset_t vnode_pager_get_filesize(
91447636 A	142	struct vnode *vp);
1c79356b	143
5d5c5d0d A	144	extern kern_return_t vnode_pager_get_pathname(
	145	struct vnode *vp,
	146	char *pathname,
	147	vm_size_t *length_p);
	148
	149	extern kern_return_t vnode_pager_get_filename(
	150	struct vnode *vp,
	151	char **filename);
	152
1c79356b A	153	#endif /* KERNEL */
	154
	155	#endif /* _VNODE_PAGER_ */