uvm_page.h revision 1.49
1/*	$OpenBSD: uvm_page.h,v 1.49 2013/05/30 15:17:59 tedu Exp $	*/
2/*	$NetBSD: uvm_page.h,v 1.19 2000/12/28 08:24:55 chs Exp $	*/
3
4/*
5 * Copyright (c) 1997 Charles D. Cranor and Washington University.
6 * Copyright (c) 1991, 1993, The Regents of the University of California.
7 *
8 * All rights reserved.
9 *
10 * This code is derived from software contributed to Berkeley by
11 * The Mach Operating System project at Carnegie-Mellon University.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 *    notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 *    notice, this list of conditions and the following disclaimer in the
20 *    documentation and/or other materials provided with the distribution.
21 * 3. All advertising materials mentioning features or use of this software
22 *    must display the following acknowledgement:
23 *	This product includes software developed by Charles D. Cranor,
24 *      Washington University, the University of California, Berkeley and
25 *      its contributors.
26 * 4. Neither the name of the University nor the names of its contributors
27 *    may be used to endorse or promote products derived from this software
28 *    without specific prior written permission.
29 *
30 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
31 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
32 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
34 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
35 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
36 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
37 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
38 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
39 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40 * SUCH DAMAGE.
41 *
42 *	@(#)vm_page.h   7.3 (Berkeley) 4/21/91
43 * from: Id: uvm_page.h,v 1.1.2.6 1998/02/04 02:31:42 chuck Exp
44 *
45 *
46 * Copyright (c) 1987, 1990 Carnegie-Mellon University.
47 * All rights reserved.
48 *
49 * Permission to use, copy, modify and distribute this software and
50 * its documentation is hereby granted, provided that both the copyright
51 * notice and this permission notice appear in all copies of the
52 * software, derivative works or modified versions, and any portions
53 * thereof, and that both notices appear in supporting documentation.
54 *
55 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
56 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
57 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
58 *
59 * Carnegie Mellon requests users of this software to return to
60 *
61 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
62 *  School of Computer Science
63 *  Carnegie Mellon University
64 *  Pittsburgh PA 15213-3890
65 *
66 * any improvements or extensions that they make and grant Carnegie the
67 * rights to redistribute these changes.
68 */
69
70#ifndef _UVM_UVM_PAGE_H_
71#define _UVM_UVM_PAGE_H_
72
73/*
74 * uvm_page.h
75 */
76
77/*
78 *	Resident memory system definitions.
79 */
80
81/*
82 *	Management of resident (logical) pages.
83 *
84 *	A small structure is kept for each resident
85 *	page, indexed by page number.  Each structure
86 *	contains a list used for manipulating pages, and
87 *	a tree structure for in object/offset lookups
88 *
89 *	In addition, the structure contains the object
90 *	and offset to which this page belongs (for pageout),
91 *	and sundry status bits.
92 *
93 *	Fields in this structure are locked either by the lock on the
94 *	object that the page belongs to (O) or by the lock on the page
95 *	queues (P) [or both].
96 */
97
98#include <uvm/uvm_extern.h>
99
100TAILQ_HEAD(pglist, vm_page);
101
102struct vm_page {
103	TAILQ_ENTRY(vm_page)	pageq;		/* queue info for FIFO
104						 * queue or free list (P) */
105	RB_ENTRY(vm_page)	objt;		/* object tree (O)*/
106
107	struct vm_anon		*uanon;		/* anon (O,P) */
108	struct uvm_object	*uobject;	/* object (O,P) */
109	voff_t			offset;		/* offset into object (O,P) */
110
111	u_int			pg_flags;	/* object flags [O or P] */
112
113	u_int			pg_version;	/* version count [O] */
114	u_int			wire_count;	/* wired down map refs [P] */
115
116	u_int			loan_count;	/* number of active loans
117						 * to read: [O or P]
118						 * to modify: [O _and_ P] */
119	paddr_t			phys_addr;	/* physical address of page */
120	psize_t			fpgsz;		/* free page range size */
121
122#ifdef __HAVE_VM_PAGE_MD
123	struct vm_page_md	mdpage;		/* pmap-specific data */
124#endif
125#if defined(UVM_PAGE_TRKOWN)
126	/* debugging fields to track page ownership */
127	pid_t			owner;		/* proc that set PG_BUSY */
128	char			*owner_tag;	/* why it was set busy */
129#endif
130};
131
132/*
133 * These are the flags defined for vm_page.
134 *
135 * Note: PG_FILLED and PG_DIRTY are added for the filesystems.
136 */
137
138/*
139 * locking rules:
140 *   PG_ ==> locked by object lock
141 *   PQ_ ==> lock by page queue lock
142 *   PQ_FREE is locked by free queue lock and is mutex with all other PQs
143 *   pg_flags may only be changed using the atomic operations.
144 *
145 * PG_ZERO is used to indicate that a page has been pre-zero'd.  This flag
146 * is only set when the page is on no queues, and is cleared when the page
147 * is placed on the free list.
148 */
149
150#define	PG_BUSY		0x00000001	/* page is locked */
151#define	PG_WANTED	0x00000002	/* someone is waiting for page */
152#define	PG_TABLED	0x00000004	/* page is in VP table  */
153#define	PG_CLEAN	0x00000008	/* page has not been modified */
154#define PG_CLEANCHK	0x00000010	/* clean bit has been checked */
155#define PG_RELEASED	0x00000020	/* page released while paging */
156#define	PG_FAKE		0x00000040	/* page is not yet initialized */
157#define PG_RDONLY	0x00000080	/* page must be mapped read-only */
158#define PG_ZERO		0x00000100	/* page is pre-zero'd */
159#define PG_DEV		0x00000200	/* page is in device space, lay off */
160
161#define PG_PAGER1	0x00001000	/* pager-specific flag */
162#define PG_MASK		0x0000ffff
163
164#define PQ_FREE		0x00010000	/* page is on free list */
165#define PQ_INACTIVE	0x00020000	/* page is in inactive list */
166#define PQ_ACTIVE	0x00040000	/* page is in active list */
167#define PQ_ANON		0x00100000	/* page is part of an anon, rather
168					   than an uvm_object */
169#define PQ_AOBJ		0x00200000	/* page is part of an anonymous
170					   uvm_object */
171#define PQ_SWAPBACKED	(PQ_ANON|PQ_AOBJ)
172#define	PQ_ENCRYPT	0x00400000	/* page needs {en,de}cryption */
173#define PQ_MASK		0x00ff0000
174
175#define PG_PMAP0	0x01000000	/* Used by some pmaps. */
176#define PG_PMAP1	0x02000000	/* Used by some pmaps. */
177#define PG_PMAP2	0x04000000	/* Used by some pmaps. */
178#define PG_PMAP3	0x08000000	/* Used by some pmaps. */
179
180/*
181 * physical memory layout structure
182 *
183 * MD vmparam.h must #define:
184 *   VM_PHYSEG_MAX = max number of physical memory segments we support
185 *		   (if this is "1" then we revert to a "contig" case)
186 *   VM_PHYSSEG_STRAT: memory sort/search options (for VM_PHYSEG_MAX > 1)
187 * 	- VM_PSTRAT_RANDOM:   linear search (random order)
188 *	- VM_PSTRAT_BSEARCH:  binary search (sorted by address)
189 *	- VM_PSTRAT_BIGFIRST: linear search (sorted by largest segment first)
190 *      - others?
191 *   XXXCDC: eventually we should purge all left-over global variables...
192 */
193#define VM_PSTRAT_RANDOM	1
194#define VM_PSTRAT_BSEARCH	2
195#define VM_PSTRAT_BIGFIRST	3
196
197/*
198 * vm_physmemseg: describes one segment of physical memory
199 */
200struct vm_physseg {
201	paddr_t	start;			/* PF# of first page in segment */
202	paddr_t	end;			/* (PF# of last page in segment) + 1 */
203	paddr_t	avail_start;		/* PF# of first free page in segment */
204	paddr_t	avail_end;		/* (PF# of last free page in segment) +1  */
205	struct	vm_page *pgs;		/* vm_page structures (from start) */
206	struct	vm_page *lastpg;	/* vm_page structure for end */
207#ifdef __HAVE_PMAP_PHYSSEG
208	struct	pmap_physseg pmseg;	/* pmap specific (MD) data */
209#endif
210};
211
212#ifdef _KERNEL
213
214/*
215 * globals
216 */
217
218extern boolean_t vm_page_zero_enable;
219
220/*
221 * physical memory config is stored in vm_physmem.
222 */
223
224extern struct vm_physseg vm_physmem[VM_PHYSSEG_MAX];
225extern int vm_nphysseg;
226
227/*
228 * prototypes: the following prototypes define the interface to pages
229 */
230
231void		uvm_page_init(vaddr_t *, vaddr_t *);
232#if defined(UVM_PAGE_TRKOWN)
233void		uvm_page_own(struct vm_page *, char *);
234#endif
235#if !defined(PMAP_STEAL_MEMORY)
236boolean_t	uvm_page_physget(paddr_t *);
237#endif
238void		uvm_pageidlezero(void);
239
240void		uvm_pageactivate(struct vm_page *);
241vaddr_t		uvm_pageboot_alloc(vsize_t);
242void		uvm_pagecopy(struct vm_page *, struct vm_page *);
243void		uvm_pagedeactivate(struct vm_page *);
244void		uvm_pagefree(struct vm_page *);
245void		uvm_page_unbusy(struct vm_page **, int);
246struct vm_page	*uvm_pagelookup(struct uvm_object *, voff_t);
247void		uvm_pageunwire(struct vm_page *);
248void		uvm_pagewait(struct vm_page *, int);
249void		uvm_pagewake(struct vm_page *);
250void		uvm_pagewire(struct vm_page *);
251void		uvm_pagezero(struct vm_page *);
252void		uvm_pagealloc_pg(struct vm_page *, struct uvm_object *,
253		    voff_t, struct vm_anon *);
254
255struct uvm_constraint_range; /* XXX move to uvm_extern.h? */
256psize_t		uvm_pagecount(struct uvm_constraint_range*);
257
258#if  VM_PHYSSEG_MAX == 1
259/*
260 * Inline functions for archs like the vax where function calls are expensive.
261 */
262/*
263 * vm_physseg_find: find vm_physseg structure that belongs to a PA
264 */
265static __inline int
266vm_physseg_find(paddr_t pframe, int *offp)
267{
268	/* 'contig' case */
269	if (pframe >= vm_physmem[0].start && pframe < vm_physmem[0].end) {
270		if (offp)
271			*offp = pframe - vm_physmem[0].start;
272		return(0);
273	}
274	return(-1);
275}
276
277/*
278 * PHYS_TO_VM_PAGE: find vm_page for a PA.   used by MI code to get vm_pages
279 * back from an I/O mapping (ugh!).   used in some MD code as well.
280 */
281static __inline struct vm_page *
282PHYS_TO_VM_PAGE(paddr_t pa)
283{
284	paddr_t pf = atop(pa);
285	int	off;
286	int	psi;
287
288	psi = vm_physseg_find(pf, &off);
289
290	return ((psi == -1) ? NULL : &vm_physmem[psi].pgs[off]);
291}
292#else
293/* if VM_PHYSSEG_MAX > 1 they're not inline, they're in uvm_page.c. */
294struct vm_page	*PHYS_TO_VM_PAGE(paddr_t);
295int		vm_physseg_find(paddr_t, int *);
296#endif
297
298/*
299 * macros
300 */
301
302#define uvm_lock_pageq()	/* lock */
303#define uvm_unlock_pageq()	/* unlock */
304#define uvm_lock_fpageq()	mtx_enter(&uvm.fpageqlock);
305#define uvm_unlock_fpageq()	mtx_leave(&uvm.fpageqlock);
306
307#define	UVM_PAGEZERO_TARGET	(uvmexp.free)
308
309#define VM_PAGE_TO_PHYS(entry)	((entry)->phys_addr)
310
311#define VM_PAGE_IS_FREE(entry)  ((entry)->pg_flags & PQ_FREE)
312
313#define	PADDR_IS_DMA_REACHABLE(paddr)	\
314	(dma_constraint.ucr_low <= paddr && dma_constraint.ucr_high > paddr)
315
316#endif /* _KERNEL */
317
318#endif /* _UVM_UVM_PAGE_H_ */
319