[apple/xnu.git] / osfmk / vm / vm_page.h

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
 * 
 * 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. 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_HEADER_END@
 */
/*
 * @OSF_COPYRIGHT@
 */
/* 
 * Mach Operating System
 * Copyright (c) 1991,1990,1989,1988 Carnegie Mellon University
 * All Rights Reserved.
 * 
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 * 
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 * 
 * Carnegie Mellon requests users of this software to return to
 * 
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 * 
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */
/*
 */
/*
 *	File:	vm/vm_page.h
 *	Author:	Avadis Tevanian, Jr., Michael Wayne Young
 *	Date:	1985
 *
 *	Resident memory system definitions.
 */

#ifndef	_VM_VM_PAGE_H_
#define _VM_VM_PAGE_H_

#include <mach/boolean.h>
#include <mach/vm_prot.h>
#include <mach/vm_param.h>
#include <vm/vm_object.h>
#include <kern/queue.h>
#include <kern/lock.h>

#include <kern/macro_help.h>

/* 
 * Each page entered on the inactive queue obtains a ticket from a
 * particular ticket roll.  Pages granted tickets from a particular 
 * roll  generally flow through the queue as a group.  In this way when a
 * page with a ticket from a particular roll is pulled from the top of the
 * queue it is extremely likely that the pages near the top will have tickets
 * from the same or adjacent rolls.  In this way the proximity to the top
 * of the queue can be loosely ascertained by determining the identity of
 * the roll the pages ticket came from. 
 */


extern int	vm_page_ticket_roll;
extern int	vm_page_ticket;


#define VM_PAGE_TICKETS_IN_ROLL  512
#define VM_PAGE_TICKET_ROLL_IDS  16

/*
 *	Management of resident (logical) pages.
 *
 *	A small structure is kept for each resident
 *	page, indexed by page number.  Each structure
 *	is an element of several lists:
 *
 *		A hash table bucket used to quickly
 *		perform object/offset lookups
 *
 *		A list of all pages for a given object,
 *		so they can be quickly deactivated at
 *		time of deallocation.
 *
 *		An ordered list of pages due for pageout.
 *
 *	In addition, the structure contains the object
 *	and offset to which this page belongs (for pageout),
 *	and sundry status bits.
 *
 *	Fields in this structure are locked either by the lock on the
 *	object that the page belongs to (O) or by the lock on the page
 *	queues (P).  [Some fields require that both locks be held to
 *	change that field; holding either lock is sufficient to read.]
 */

struct vm_page {
	queue_chain_t	pageq;		/* queue info for FIFO
					 * queue or free list (P) */
	queue_chain_t	listq;		/* all pages in same object (O) */
	struct vm_page	*next;		/* VP bucket link (O) */

	vm_object_t	object;		/* which object am I in (O&P) */
	vm_object_offset_t offset;	/* offset into that object (O,P) */

	unsigned int	wire_count:16,	/* how many wired down maps use me? (O&P) */
			page_ticket:4,	/* age of the page on the       */
					/* inactive queue.		    */
	/* boolean_t */	inactive:1,	/* page is in inactive list (P) */
			active:1,	/* page is in active list (P) */
			laundry:1,	/* page is being cleaned now (P)*/
			free:1,		/* page is on free list (P) */
			reference:1,	/* page has been used (P) */
			pageout:1,	/* page wired & busy for pageout (P) */
			gobbled:1,      /* page used internally (P) */
			private:1,	/* Page should not be returned to
					 *  the free list (O) */
			zero_fill:1,
			:0;

	unsigned int
	                page_error:8,   /* error from I/O operations */
	/* boolean_t */	busy:1,		/* page is in transit (O) */
			wanted:1,	/* someone is waiting for page (O) */
			tabled:1,	/* page is in VP table (O) */
			fictitious:1,	/* Physical page doesn't exist (O) */
			no_isync:1,     /* page has not been instruction synced */
			absent:1,	/* Data has been requested, but is
					 *  not yet available (O) */
			error:1,	/* Data manager was unable to provide
					 *  data due to error (O) */
			dirty:1,	/* Page must be cleaned (O) */
			cleaning:1,	/* Page clean has begun (O) */
			precious:1,	/* Page is precious; data must be
					 *  returned even if clean (O) */
			clustered:1,	/* page is not the faulted page (O) */
			overwriting:1,  /* Request to unlock has been made
					 * without having data. (O)
					 * [See vm_fault_page_overwrite] */
			restart:1,	/* Page was pushed higher in shadow
					   chain by copy_call-related pagers;
					   start again at top of chain */
			lock_supplied:1,/* protection supplied by pager (O) */
	/* vm_prot_t */	page_lock:3,	/* Uses prohibited by pager (O) */
	/* vm_prot_t */	unlock_request:3,/* Outstanding unlock request (O) */
			unusual:1,	/* Page is absent, error, restart or
					   page locked */
	  		discard_request:1,/* a memory_object_discard_request()
					   * has been sent */
			list_req_pending:1, /* pagein/pageout alt mechanism */
					    /* allows creation of list      */
					    /* requests on pages that are   */
					    /* actively being paged.        */
			dump_cleaning:1;   /* set by the pageout daemon when */
					   /* a page being cleaned is       */
					   /* encountered and targeted as   */
					   /* a pageout candidate           */
        /* we've used up all 32 bits */

	vm_offset_t	phys_page;	/* Physical address of page, passed
					 *  to pmap_enter (read-only) */
};

typedef struct vm_page	*vm_page_t;

#define VM_PAGE_NULL		((vm_page_t) 0)
#define NEXT_PAGE(m)    ((vm_page_t) (m)->pageq.next)

/*
 * XXX	The unusual bit should not be necessary.  Most of the bit
 * XXX	fields above really want to be masks.
 */

/*
 *	For debugging, this macro can be defined to perform
 *	some useful check on a page structure.
 */

#define VM_PAGE_CHECK(mem)

/*
 *	Each pageable resident page falls into one of three lists:
 *
 *	free	
 *		Available for allocation now.
 *	inactive
 *		Not referenced in any map, but still has an
 *		object/offset-page mapping, and may be dirty.
 *		This is the list of pages that should be
 *		paged out next.
 *	active
 *		A list of pages which have been placed in
 *		at least one physical map.  This list is
 *		ordered, in LRU-like fashion.
 */

extern
vm_page_t	vm_page_queue_free;	/* memory free queue */
extern
vm_page_t	vm_page_queue_fictitious;	/* fictitious free queue */
extern
queue_head_t	vm_page_queue_active;	/* active memory queue */
extern
queue_head_t	vm_page_queue_inactive;	/* inactive memory queue */
queue_head_t	vm_page_queue_zf;	/* inactive memory queue for zero fill */

extern
vm_offset_t	first_phys_addr;	/* physical address for first_page */
extern
vm_offset_t	last_phys_addr;		/* physical address for last_page */

extern
int	vm_page_free_count;	/* How many pages are free? */
extern
int	vm_page_fictitious_count;/* How many fictitious pages are free? */
extern
int	vm_page_active_count;	/* How many pages are active? */
extern
int	vm_page_inactive_count;	/* How many pages are inactive? */
extern
int	vm_page_wire_count;	/* How many pages are wired? */
extern
int	vm_page_free_target;	/* How many do we want free? */
extern
int	vm_page_free_min;	/* When to wakeup pageout */
extern
int	vm_page_inactive_target;/* How many do we want inactive? */
extern
int	vm_page_free_reserved;	/* How many pages reserved to do pageout */
extern
int	vm_page_laundry_count;	/* How many pages being laundered? */
extern
int	vm_page_burst_count;	/* How many pages being laundered to EMM? */
extern
int	vm_page_throttled_count;/* Count of zero-fill allocations throttled */

decl_mutex_data(,vm_page_queue_lock)
				/* lock on active and inactive page queues */
decl_mutex_data(,vm_page_queue_free_lock)
				/* lock on free page queue */
decl_simple_lock_data(extern,vm_page_preppin_lock)	/* lock for prep/pin */
decl_mutex_data(,vm_page_zero_fill_lock)

extern unsigned int	vm_page_free_wanted;
				/* how many threads are waiting for memory */

extern vm_offset_t	vm_page_fictitious_addr;
				/* (fake) phys_addr of fictitious pages */

/*
 * Prototypes for functions exported by this module.
 */
extern void		vm_page_bootstrap(
					vm_offset_t	*startp,
					vm_offset_t	*endp);

extern void		vm_page_module_init(void);

extern void		vm_page_create(
					ppnum_t		start,
					ppnum_t		end);

extern vm_page_t	vm_page_lookup(
					vm_object_t		object,
					vm_object_offset_t	offset);

extern vm_page_t	vm_page_grab_fictitious(void);

extern void		vm_page_release_fictitious(
					vm_page_t page);

extern boolean_t	vm_page_convert(
					vm_page_t	page);

extern void		vm_page_more_fictitious(void);

extern int		vm_pool_low(void);

extern vm_page_t	vm_page_grab(void);

extern void		vm_page_release(
					vm_page_t	page);

extern void		vm_page_release_limbo(
					vm_page_t	page);

extern void		vm_page_limbo_exchange(
					vm_page_t	limbo_m,
					vm_page_t	new_m);

extern boolean_t	vm_page_wait(
					int		interruptible );

extern vm_page_t	vm_page_alloc(
					vm_object_t		object,
					vm_object_offset_t	offset);

extern void		vm_page_init(
					vm_page_t	page,
					ppnum_t		phys_page);

extern void		vm_page_free(
					vm_page_t	page);

extern void		vm_page_activate(
					vm_page_t	page);

extern void		vm_page_deactivate(
					vm_page_t	page);

extern void		vm_page_rename(
					vm_page_t		page,
					vm_object_t		new_object,
					vm_object_offset_t	new_offset);

extern void		vm_page_insert(
					vm_page_t		page,
					vm_object_t		object,
					vm_object_offset_t	offset);

extern void		vm_page_replace(
					vm_page_t		mem,
					vm_object_t		object,
					vm_object_offset_t	offset);

extern void		vm_page_remove(
					vm_page_t	page);

extern void		vm_page_zero_fill(
					vm_page_t	page);

extern void		vm_page_part_zero_fill(
					vm_page_t	m,
					vm_offset_t	m_pa,
					vm_size_t	len);

extern void		vm_page_copy(
					vm_page_t	src_page,
					vm_page_t	dest_page);

extern void		vm_page_part_copy(
					vm_page_t	src_m,
					vm_offset_t	src_pa,
					vm_page_t	dst_m,
					vm_offset_t	dst_pa,
					vm_size_t	len);

extern void		vm_page_wire(
					vm_page_t	page);

extern void		vm_page_unwire(
					vm_page_t	page);

extern void		vm_set_page_size(void);

extern void		vm_page_gobble(
				        vm_page_t      page);

/*
 *	Functions implemented as macros. m->wanted and m->busy are
 *	protected by the object lock.
 */

#define PAGE_ASSERT_WAIT(m, interruptible)			\
		(((m)->wanted = TRUE),				\
		 assert_wait((event_t) (m), (interruptible)))

#define PAGE_SLEEP(o, m, interruptible)				\
		(((m)->wanted = TRUE),				\
		 thread_sleep_vm_object((o), (m), (interruptible)))

#define PAGE_WAKEUP_DONE(m)					\
		MACRO_BEGIN					\
		(m)->busy = FALSE;				\
		if ((m)->wanted) {				\
			(m)->wanted = FALSE;			\
			thread_wakeup((event_t) (m));		\
		}						\
		MACRO_END

#define PAGE_WAKEUP(m)						\
		MACRO_BEGIN					\
		if ((m)->wanted) {				\
			(m)->wanted = FALSE;			\
			thread_wakeup((event_t) (m));		\
		}						\
		MACRO_END

#define VM_PAGE_FREE(p) 			\
		MACRO_BEGIN			\
		vm_page_lock_queues();		\
		vm_page_free(p);		\
		vm_page_unlock_queues();	\
		MACRO_END

#define VM_PAGE_GRAB_FICTITIOUS(M)					\
		MACRO_BEGIN						\
		while ((M = vm_page_grab_fictitious()) == VM_PAGE_NULL)	\
			vm_page_more_fictitious();			\
		MACRO_END

#define VM_PAGE_THROTTLED()						\
		(vm_page_free_count < vm_page_free_min &&		\
		 !current_thread()->vm_privilege && 			\
		 ++vm_page_throttled_count)

#define	VM_PAGE_WAIT()		((void)vm_page_wait(THREAD_UNINT))

#define vm_page_lock_queues()	mutex_lock(&vm_page_queue_lock)
#define vm_page_unlock_queues()	mutex_unlock(&vm_page_queue_lock)
#define vm_page_pin_lock()	simple_lock(&vm_page_preppin_lock)
#define vm_page_pin_unlock()	simple_unlock(&vm_page_preppin_lock)

#define VM_PAGE_QUEUES_REMOVE(mem)				\
	MACRO_BEGIN						\
	if (mem->active) {					\
		assert(!mem->inactive);				\
		queue_remove(&vm_page_queue_active,		\
			mem, vm_page_t, pageq);			\
		mem->active = FALSE;				\
		if (!mem->fictitious)				\
			vm_page_active_count--;			\
	}							\
								\
	if (mem->inactive) {					\
		assert(!mem->active);				\
		if (mem->zero_fill) {				\
			queue_remove(&vm_page_queue_zf,		\
			mem, vm_page_t, pageq);			\
		} else {					\
			queue_remove(&vm_page_queue_inactive,	\
			mem, vm_page_t, pageq);			\
		}						\
		mem->inactive = FALSE;				\
		if (!mem->fictitious)				\
			vm_page_inactive_count--;		\
	}							\
	MACRO_END

#endif	/* _VM_VM_PAGE_H_ */
Commit	Line	Data
1c79356b A	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
43866e37	6	* Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
1c79356b	7	*
43866e37 A	8	* This file contains Original Code and/or Modifications of Original Code
	9	* as defined in and that are subject to the Apple Public Source License
	10	* Version 2.0 (the 'License'). You may not use this file except in
	11	* compliance with the License. Please obtain a copy of the License at
	12	* http://www.opensource.apple.com/apsl/ and read it before using this
	13	* file.
	14	*
	15	* The Original Code and all software distributed under the License are
	16	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
1c79356b A	17	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
1c79356b A	18	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
43866e37 A	19	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	20	* Please see the License for the specific language governing rights and
	21	* limitations under the License.
1c79356b A	22	*
	23	* @APPLE_LICENSE_HEADER_END@
	24	*/
	25	/*
	26	* @OSF_COPYRIGHT@
	27	*/
	28	/*
	29	* Mach Operating System
	30	* Copyright (c) 1991,1990,1989,1988 Carnegie Mellon University
	31	* All Rights Reserved.
	32	*
	33	* Permission to use, copy, modify and distribute this software and its
	34	* documentation is hereby granted, provided that both the copyright
	35	* notice and this permission notice appear in all copies of the
	36	* software, derivative works or modified versions, and any portions
	37	* thereof, and that both notices appear in supporting documentation.
	38	*
	39	* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
	40	* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
	41	* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
	42	*
	43	* Carnegie Mellon requests users of this software to return to
	44	*
	45	* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
	46	* School of Computer Science
	47	* Carnegie Mellon University
	48	* Pittsburgh PA 15213-3890
	49	*
	50	* any improvements or extensions that they make and grant Carnegie Mellon
	51	* the rights to redistribute these changes.
	52	*/
	53	/*
	54	*/
	55	/*
	56	* File: vm/vm_page.h
	57	* Author: Avadis Tevanian, Jr., Michael Wayne Young
	58	* Date: 1985
	59	*
	60	* Resident memory system definitions.
	61	*/
	62
	63	#ifndef _VM_VM_PAGE_H_
	64	#define _VM_VM_PAGE_H_
	65
	66	#include <mach/boolean.h>
	67	#include <mach/vm_prot.h>
	68	#include <mach/vm_param.h>
	69	#include <vm/vm_object.h>
	70	#include <kern/queue.h>
	71	#include <kern/lock.h>
	72
	73	#include <kern/macro_help.h>
	74
0b4e3aa0 A	75	/*
	76	* Each page entered on the inactive queue obtains a ticket from a
	77	* particular ticket roll. Pages granted tickets from a particular
	78	* roll generally flow through the queue as a group. In this way when a
	79	* page with a ticket from a particular roll is pulled from the top of the
	80	* queue it is extremely likely that the pages near the top will have tickets
	81	* from the same or adjacent rolls. In this way the proximity to the top
	82	* of the queue can be loosely ascertained by determining the identity of
	83	* the roll the pages ticket came from.
	84	*/
	85
	86
	87	extern int vm_page_ticket_roll;
	88	extern int vm_page_ticket;
	89
9bccf70c	90
0b4e3aa0 A	91	#define VM_PAGE_TICKETS_IN_ROLL 512
	92	#define VM_PAGE_TICKET_ROLL_IDS 16
	93
1c79356b A	94	/*
	95	* Management of resident (logical) pages.
	96	*
	97	* A small structure is kept for each resident
	98	* page, indexed by page number. Each structure
	99	* is an element of several lists:
	100	*
	101	* A hash table bucket used to quickly
	102	* perform object/offset lookups
	103	*
	104	* A list of all pages for a given object,
	105	* so they can be quickly deactivated at
	106	* time of deallocation.
	107	*
	108	* An ordered list of pages due for pageout.
	109	*
	110	* In addition, the structure contains the object
	111	* and offset to which this page belongs (for pageout),
	112	* and sundry status bits.
	113	*
	114	* Fields in this structure are locked either by the lock on the
	115	* object that the page belongs to (O) or by the lock on the page
	116	* queues (P). [Some fields require that both locks be held to
	117	* change that field; holding either lock is sufficient to read.]
	118	*/
	119
	120	struct vm_page {
	121	queue_chain_t pageq; /* queue info for FIFO
	122	* queue or free list (P) */
	123	queue_chain_t listq; /* all pages in same object (O) */
	124	struct vm_page next; / VP bucket link (O) */
	125
	126	vm_object_t object; /* which object am I in (O&P) */
	127	vm_object_offset_t offset; /* offset into that object (O,P) */
	128
	129	unsigned int wire_count:16, /* how many wired down maps use me? (O&P) */
0b4e3aa0 A	130	page_ticket:4, /* age of the page on the */
0b4e3aa0 A	131	/* inactive queue. */
1c79356b A	132	/* boolean_t / inactive:1, / page is in inactive list (P) */
	133	active:1, /* page is in active list (P) */
	134	laundry:1, /* page is being cleaned now (P)*/
	135	free:1, /* page is on free list (P) */
	136	reference:1, /* page has been used (P) */
1c79356b	137	pageout:1, /* page wired & busy for pageout (P) */
0b4e3aa0 A	138	gobbled:1, /* page used internally (P) */
	139	private:1, /* Page should not be returned to
	140	* the free list (O) */
9bccf70c	141	zero_fill:1,
0b4e3aa0	142	:0;
1c79356b A	143
1c79356b A	144	unsigned int
0b4e3aa0	145	page_error:8, /* error from I/O operations */
1c79356b A	146	/* boolean_t / busy:1, / page is in transit (O) */
	147	wanted:1, /* someone is waiting for page (O) */
	148	tabled:1, /* page is in VP table (O) */
	149	fictitious:1, /* Physical page doesn't exist (O) */
0b4e3aa0	150	no_isync:1, /* page has not been instruction synced */
1c79356b A	151	absent:1, /* Data has been requested, but is
	152	* not yet available (O) */
	153	error:1, /* Data manager was unable to provide
	154	* data due to error (O) */
	155	dirty:1, /* Page must be cleaned (O) */
	156	cleaning:1, /* Page clean has begun (O) */
	157	precious:1, /* Page is precious; data must be
	158	* returned even if clean (O) */
	159	clustered:1, /* page is not the faulted page (O) */
	160	overwriting:1, /* Request to unlock has been made
	161	* without having data. (O)
	162	* [See vm_fault_page_overwrite] */
	163	restart:1, /* Page was pushed higher in shadow
	164	chain by copy_call-related pagers;
	165	start again at top of chain */
	166	lock_supplied:1,/* protection supplied by pager (O) */
	167	/* vm_prot_t / page_lock:3, / Uses prohibited by pager (O) */
	168	/* vm_prot_t / unlock_request:3,/ Outstanding unlock request (O) */
	169	unusual:1, /* Page is absent, error, restart or
	170	page locked */
	171	discard_request:1,/* a memory_object_discard_request()
	172	* has been sent */
	173	list_req_pending:1, /* pagein/pageout alt mechanism */
	174	/* allows creation of list */
	175	/* requests on pages that are */
	176	/* actively being paged. */
0b4e3aa0 A	177	dump_cleaning:1; /* set by the pageout daemon when */
	178	/* a page being cleaned is */
	179	/* encountered and targeted as */
	180	/* a pageout candidate */
	181	/* we've used up all 32 bits */
1c79356b	182
55e303ae	183	vm_offset_t phys_page; /* Physical address of page, passed
1c79356b	184	* to pmap_enter (read-only) */
1c79356b A	185	};
	186
	187	typedef struct vm_page *vm_page_t;
	188
1c79356b A	189	#define VM_PAGE_NULL ((vm_page_t) 0)
	190	#define NEXT_PAGE(m) ((vm_page_t) (m)->pageq.next)
	191
	192	/*
	193	* XXX The unusual bit should not be necessary. Most of the bit
	194	* XXX fields above really want to be masks.
	195	*/
	196
	197	/*
	198	* For debugging, this macro can be defined to perform
	199	* some useful check on a page structure.
	200	*/
	201
	202	#define VM_PAGE_CHECK(mem)
	203
	204	/*
	205	* Each pageable resident page falls into one of three lists:
	206	*
	207	* free
	208	* Available for allocation now.
	209	* inactive
	210	* Not referenced in any map, but still has an
	211	* object/offset-page mapping, and may be dirty.
	212	* This is the list of pages that should be
	213	* paged out next.
	214	* active
	215	* A list of pages which have been placed in
	216	* at least one physical map. This list is
	217	* ordered, in LRU-like fashion.
	218	*/
	219
	220	extern
	221	vm_page_t vm_page_queue_free; /* memory free queue */
	222	extern
	223	vm_page_t vm_page_queue_fictitious; /* fictitious free queue */
	224	extern
	225	queue_head_t vm_page_queue_active; /* active memory queue */
	226	extern
	227	queue_head_t vm_page_queue_inactive; /* inactive memory queue */
9bccf70c	228	queue_head_t vm_page_queue_zf; /* inactive memory queue for zero fill */
1c79356b A	229
	230	extern
	231	vm_offset_t first_phys_addr; /* physical address for first_page */
	232	extern
	233	vm_offset_t last_phys_addr; /* physical address for last_page */
	234
	235	extern
	236	int vm_page_free_count; /* How many pages are free? */
	237	extern
	238	int vm_page_fictitious_count;/* How many fictitious pages are free? */
	239	extern
	240	int vm_page_active_count; /* How many pages are active? */
	241	extern
	242	int vm_page_inactive_count; /* How many pages are inactive? */
	243	extern
	244	int vm_page_wire_count; /* How many pages are wired? */
	245	extern
	246	int vm_page_free_target; /* How many do we want free? */
	247	extern
	248	int vm_page_free_min; /* When to wakeup pageout */
	249	extern
	250	int vm_page_inactive_target;/* How many do we want inactive? */
	251	extern
	252	int vm_page_free_reserved; /* How many pages reserved to do pageout */
	253	extern
	254	int vm_page_laundry_count; /* How many pages being laundered? */
55e303ae A	255	extern
	256	int vm_page_burst_count; /* How many pages being laundered to EMM? */
	257	extern
	258	int vm_page_throttled_count;/* Count of zero-fill allocations throttled */
1c79356b A	259
	260	decl_mutex_data(,vm_page_queue_lock)
	261	/* lock on active and inactive page queues */
	262	decl_mutex_data(,vm_page_queue_free_lock)
	263	/* lock on free page queue */
	264	decl_simple_lock_data(extern,vm_page_preppin_lock) /* lock for prep/pin */
9bccf70c	265	decl_mutex_data(,vm_page_zero_fill_lock)
1c79356b A	266
	267	extern unsigned int vm_page_free_wanted;
	268	/* how many threads are waiting for memory */
	269
	270	extern vm_offset_t vm_page_fictitious_addr;
	271	/* (fake) phys_addr of fictitious pages */
	272
	273	/*
	274	* Prototypes for functions exported by this module.
	275	*/
	276	extern void vm_page_bootstrap(
	277	vm_offset_t *startp,
	278	vm_offset_t *endp);
	279
	280	extern void vm_page_module_init(void);
	281
	282	extern void vm_page_create(
55e303ae A	283	ppnum_t start,
55e303ae A	284	ppnum_t end);
1c79356b A	285
	286	extern vm_page_t vm_page_lookup(
	287	vm_object_t object,
	288	vm_object_offset_t offset);
	289
	290	extern vm_page_t vm_page_grab_fictitious(void);
	291
	292	extern void vm_page_release_fictitious(
	293	vm_page_t page);
	294
	295	extern boolean_t vm_page_convert(
	296	vm_page_t page);
	297
	298	extern void vm_page_more_fictitious(void);
	299
	300	extern int vm_pool_low(void);
	301
	302	extern vm_page_t vm_page_grab(void);
	303
	304	extern void vm_page_release(
	305	vm_page_t page);
	306
	307	extern void vm_page_release_limbo(
	308	vm_page_t page);
	309
	310	extern void vm_page_limbo_exchange(
	311	vm_page_t limbo_m,
	312	vm_page_t new_m);
	313
	314	extern boolean_t vm_page_wait(
	315	int interruptible );
	316
	317	extern vm_page_t vm_page_alloc(
	318	vm_object_t object,
	319	vm_object_offset_t offset);
	320
	321	extern void vm_page_init(
	322	vm_page_t page,
55e303ae	323	ppnum_t phys_page);
1c79356b A	324
	325	extern void vm_page_free(
	326	vm_page_t page);
	327
	328	extern void vm_page_activate(
	329	vm_page_t page);
	330
	331	extern void vm_page_deactivate(
	332	vm_page_t page);
	333
	334	extern void vm_page_rename(
	335	vm_page_t page,
	336	vm_object_t new_object,
	337	vm_object_offset_t new_offset);
	338
	339	extern void vm_page_insert(
	340	vm_page_t page,
	341	vm_object_t object,
	342	vm_object_offset_t offset);
	343
	344	extern void vm_page_replace(
	345	vm_page_t mem,
	346	vm_object_t object,
	347	vm_object_offset_t offset);
	348
	349	extern void vm_page_remove(
	350	vm_page_t page);
	351
	352	extern void vm_page_zero_fill(
	353	vm_page_t page);
	354
	355	extern void vm_page_part_zero_fill(
	356	vm_page_t m,
	357	vm_offset_t m_pa,
	358	vm_size_t len);
	359
	360	extern void vm_page_copy(
	361	vm_page_t src_page,
	362	vm_page_t dest_page);
	363
	364	extern void vm_page_part_copy(
	365	vm_page_t src_m,
	366	vm_offset_t src_pa,
	367	vm_page_t dst_m,
	368	vm_offset_t dst_pa,
	369	vm_size_t len);
	370
	371	extern void vm_page_wire(
	372	vm_page_t page);
	373
	374	extern void vm_page_unwire(
	375	vm_page_t page);
	376
	377	extern void vm_set_page_size(void);
	378
	379	extern void vm_page_gobble(
	380	vm_page_t page);
	381
1c79356b A	382	/*
	383	* Functions implemented as macros. m->wanted and m->busy are
	384	* protected by the object lock.
	385	*/
	386
	387	#define PAGE_ASSERT_WAIT(m, interruptible) \
9bccf70c A	388	(((m)->wanted = TRUE), \
	389	assert_wait((event_t) (m), (interruptible)))
	390
	391	#define PAGE_SLEEP(o, m, interruptible) \
	392	(((m)->wanted = TRUE), \
	393	thread_sleep_vm_object((o), (m), (interruptible)))
1c79356b A	394
	395	#define PAGE_WAKEUP_DONE(m) \
	396	MACRO_BEGIN \
	397	(m)->busy = FALSE; \
	398	if ((m)->wanted) { \
	399	(m)->wanted = FALSE; \
	400	thread_wakeup((event_t) (m)); \
	401	} \
	402	MACRO_END
	403
	404	#define PAGE_WAKEUP(m) \
	405	MACRO_BEGIN \
	406	if ((m)->wanted) { \
	407	(m)->wanted = FALSE; \
	408	thread_wakeup((event_t) (m)); \
	409	} \
	410	MACRO_END
	411
	412	#define VM_PAGE_FREE(p) \
	413	MACRO_BEGIN \
	414	vm_page_lock_queues(); \
	415	vm_page_free(p); \
	416	vm_page_unlock_queues(); \
	417	MACRO_END
	418
	419	#define VM_PAGE_GRAB_FICTITIOUS(M) \
	420	MACRO_BEGIN \
	421	while ((M = vm_page_grab_fictitious()) == VM_PAGE_NULL) \
	422	vm_page_more_fictitious(); \
	423	MACRO_END
	424
	425	#define VM_PAGE_THROTTLED() \
55e303ae A	426	(vm_page_free_count < vm_page_free_min && \
	427	!current_thread()->vm_privilege && \
	428	++vm_page_throttled_count)
1c79356b A	429
	430	#define VM_PAGE_WAIT() ((void)vm_page_wait(THREAD_UNINT))
	431
	432	#define vm_page_lock_queues() mutex_lock(&vm_page_queue_lock)
	433	#define vm_page_unlock_queues() mutex_unlock(&vm_page_queue_lock)
	434	#define vm_page_pin_lock() simple_lock(&vm_page_preppin_lock)
	435	#define vm_page_pin_unlock() simple_unlock(&vm_page_preppin_lock)
	436
	437	#define VM_PAGE_QUEUES_REMOVE(mem) \
	438	MACRO_BEGIN \
	439	if (mem->active) { \
	440	assert(!mem->inactive); \
	441	queue_remove(&vm_page_queue_active, \
	442	mem, vm_page_t, pageq); \
	443	mem->active = FALSE; \
	444	if (!mem->fictitious) \
	445	vm_page_active_count--; \
	446	} \
	447	\
	448	if (mem->inactive) { \
	449	assert(!mem->active); \
9bccf70c A	450	if (mem->zero_fill) { \
	451	queue_remove(&vm_page_queue_zf, \
	452	mem, vm_page_t, pageq); \
	453	} else { \
	454	queue_remove(&vm_page_queue_inactive, \
1c79356b	455	mem, vm_page_t, pageq); \
9bccf70c	456	} \
1c79356b A	457	mem->inactive = FALSE; \
	458	if (!mem->fictitious) \
	459	vm_page_inactive_count--; \
	460	} \
	461	MACRO_END
	462
	463	#endif /* _VM_VM_PAGE_H_ */