xref: /openbsd-src/sys/uvm/uvm_page.h (revision 2b0358df1d88d06ef4139321dd05bd5e05d91eaf)
1 /*	$OpenBSD: uvm_page.h,v 1.30 2009/04/06 17:03:51 oga 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  *	is an element of several lists:
87  *
88  *		A hash table bucket used to quickly
89  *		perform object/offset lookups
90  *
91  *		A list of all pages for a given object,
92  *		so they can be quickly deactivated at
93  *		time of deallocation.
94  *
95  *		An ordered list of pages due for pageout.
96  *
97  *	In addition, the structure contains the object
98  *	and offset to which this page belongs (for pageout),
99  *	and sundry status bits.
100  *
101  *	Fields in this structure are locked either by the lock on the
102  *	object that the page belongs to (O) or by the lock on the page
103  *	queues (P) [or both].
104  */
105 
106 #include <uvm/uvm_extern.h>
107 #include <uvm/uvm_pglist.h>
108 
109 struct vm_page {
110 	TAILQ_ENTRY(vm_page)	pageq;		/* queue info for FIFO
111 						 * queue or free list (P) */
112 	TAILQ_ENTRY(vm_page)	hashq;		/* hash table links (O)*/
113 	TAILQ_ENTRY(vm_page)	listq;		/* pages in same object (O)*/
114 
115 	struct vm_anon		*uanon;		/* anon (O,P) */
116 	struct uvm_object	*uobject;	/* object (O,P) */
117 	voff_t			offset;		/* offset into object (O,P) */
118 
119 	u_int			pg_flags;	/* object flags [O or P] */
120 
121 	u_int			pg_version;	/* version count [O] */
122 	u_int			wire_count;	/* wired down map refs [P] */
123 
124 	u_int			loan_count;	/* number of active loans
125 						 * to read: [O or P]
126 						 * to modify: [O _and_ P] */
127 	paddr_t			phys_addr;	/* physical address of page */
128 
129 #ifdef __HAVE_VM_PAGE_MD
130 	struct vm_page_md	mdpage;		/* pmap-specific data */
131 #endif
132 #if defined(UVM_PAGE_TRKOWN)
133 	/* debugging fields to track page ownership */
134 	pid_t			owner;		/* proc that set PG_BUSY */
135 	char			*owner_tag;	/* why it was set busy */
136 #endif
137 };
138 
139 /*
140  * These are the flags defined for vm_page.
141  *
142  * Note: PG_FILLED and PG_DIRTY are added for the filesystems.
143  */
144 
145 /*
146  * locking rules:
147  *   PG_ ==> locked by object lock
148  *   PQ_ ==> lock by page queue lock
149  *   PQ_FREE is locked by free queue lock and is mutex with all other PQs
150  *   pg_flags may only be changed using the atomic operations.
151  *
152  * PG_ZERO is used to indicate that a page has been pre-zero'd.  This flag
153  * is only set when the page is on no queues, and is cleared when the page
154  * is placed on the free list.
155  */
156 
157 #define	PG_BUSY		0x00000001	/* page is locked */
158 #define	PG_WANTED	0x00000002	/* someone is waiting for page */
159 #define	PG_TABLED	0x00000004	/* page is in VP table  */
160 #define	PG_CLEAN	0x00000008	/* page has not been modified */
161 #define PG_CLEANCHK	0x00000010	/* clean bit has been checked */
162 #define PG_RELEASED	0x00000020	/* page released while paging */
163 #define	PG_FAKE		0x00000040	/* page is not yet initialized */
164 #define PG_RDONLY	0x00000080	/* page must be mapped read-only */
165 #define PG_ZERO		0x00000100	/* page is pre-zero'd */
166 
167 #define PG_PAGER1	0x00001000	/* pager-specific flag */
168 #define PG_MASK		0x0000ffff
169 
170 #define PQ_FREE		0x00010000	/* page is on free list */
171 #define PQ_INACTIVE	0x00020000	/* page is in inactive list */
172 #define PQ_ACTIVE	0x00040000	/* page is in active list */
173 #define PQ_ANON		0x00100000	/* page is part of an anon, rather
174 					   than an uvm_object */
175 #define PQ_AOBJ		0x00200000	/* page is part of an anonymous
176 					   uvm_object */
177 #define PQ_SWAPBACKED	(PQ_ANON|PQ_AOBJ)
178 #define	PQ_ENCRYPT	0x00400000	/* page needs {en,de}cryption */
179 #define PQ_MASK		0x00ff0000
180 
181 #define PG_PMAP0	0x01000000	/* Used by some pmaps. */
182 #define PG_PMAP1	0x02000000	/* Used by some pmaps. */
183 #define PG_PMAP2	0x04000000	/* Used by some pmaps. */
184 #define PG_PMAP3	0x08000000	/* Used by some pmaps. */
185 
186 /*
187  * physical memory layout structure
188  *
189  * MD vmparam.h must #define:
190  *   VM_PHYSEG_MAX = max number of physical memory segments we support
191  *		   (if this is "1" then we revert to a "contig" case)
192  *   VM_PHYSSEG_STRAT: memory sort/search options (for VM_PHYSEG_MAX > 1)
193  * 	- VM_PSTRAT_RANDOM:   linear search (random order)
194  *	- VM_PSTRAT_BSEARCH:  binary search (sorted by address)
195  *	- VM_PSTRAT_BIGFIRST: linear search (sorted by largest segment first)
196  *      - others?
197  *   XXXCDC: eventually we should purge all left-over global variables...
198  */
199 #define VM_PSTRAT_RANDOM	1
200 #define VM_PSTRAT_BSEARCH	2
201 #define VM_PSTRAT_BIGFIRST	3
202 
203 /*
204  * vm_physmemseg: describes one segment of physical memory
205  */
206 struct vm_physseg {
207 	paddr_t	start;			/* PF# of first page in segment */
208 	paddr_t	end;			/* (PF# of last page in segment) + 1 */
209 	paddr_t	avail_start;		/* PF# of first free page in segment */
210 	paddr_t	avail_end;		/* (PF# of last free page in segment) +1  */
211 	int	free_list;		/* which free list they belong on */
212 	struct	vm_page *pgs;		/* vm_page structures (from start) */
213 	struct	vm_page *lastpg;	/* vm_page structure for end */
214 #ifdef __HAVE_PMAP_PHYSSEG
215 	struct	pmap_physseg pmseg;	/* pmap specific (MD) data */
216 #endif
217 };
218 
219 #ifdef _KERNEL
220 
221 /*
222  * globals
223  */
224 
225 extern boolean_t vm_page_zero_enable;
226 
227 /*
228  * physical memory config is stored in vm_physmem.
229  */
230 
231 extern struct vm_physseg vm_physmem[VM_PHYSSEG_MAX];
232 extern int vm_nphysseg;
233 
234 /*
235  * prototypes: the following prototypes define the interface to pages
236  */
237 
238 void		uvm_page_init(vaddr_t *, vaddr_t *);
239 #if defined(UVM_PAGE_TRKOWN)
240 void		uvm_page_own(struct vm_page *, char *);
241 #endif
242 #if !defined(PMAP_STEAL_MEMORY)
243 boolean_t	uvm_page_physget(paddr_t *);
244 #endif
245 void		uvm_page_rehash(void);
246 void		uvm_pageidlezero(void);
247 
248 void		uvm_pageactivate(struct vm_page *);
249 vaddr_t		uvm_pageboot_alloc(vsize_t);
250 void		uvm_pagecopy(struct vm_page *, struct vm_page *);
251 void		uvm_pagedeactivate(struct vm_page *);
252 void		uvm_pagefree(struct vm_page *);
253 void		uvm_page_unbusy(struct vm_page **, int);
254 struct vm_page	*uvm_pagelookup(struct uvm_object *, voff_t);
255 void		uvm_pageunwire(struct vm_page *);
256 void		uvm_pagewait(struct vm_page *, int);
257 void		uvm_pagewake(struct vm_page *);
258 void		uvm_pagewire(struct vm_page *);
259 void		uvm_pagezero(struct vm_page *);
260 
261 int		uvm_page_lookup_freelist(struct vm_page *);
262 
263 #if  VM_PHYSSEG_MAX == 1
264 /*
265  * Inline functions for archs like the vax where function calls are expensive.
266  */
267 /*
268  * vm_physseg_find: find vm_physseg structure that belongs to a PA
269  */
270 static __inline int
271 vm_physseg_find(paddr_t pframe, int *offp)
272 {
273 	/* 'contig' case */
274 	if (pframe >= vm_physmem[0].start && pframe < vm_physmem[0].end) {
275 		if (offp)
276 			*offp = pframe - vm_physmem[0].start;
277 		return(0);
278 	}
279 	return(-1);
280 }
281 
282 /*
283  * PHYS_TO_VM_PAGE: find vm_page for a PA.   used by MI code to get vm_pages
284  * back from an I/O mapping (ugh!).   used in some MD code as well.
285  */
286 static __inline struct vm_page *
287 PHYS_TO_VM_PAGE(paddr_t pa)
288 {
289 	paddr_t pf = atop(pa);
290 	int	off;
291 	int	psi;
292 
293 	psi = vm_physseg_find(pf, &off);
294 
295 	return ((psi == -1) ? NULL : &vm_physmem[psi].pgs[off]);
296 }
297 #else
298 /* if VM_PHYSSEG_MAX > 1 they're not inline, they're in uvm_page.c. */
299 struct vm_page	*PHYS_TO_VM_PAGE(paddr_t);
300 int		vm_physseg_find(paddr_t, int *);
301 #endif
302 
303 /*
304  * macros
305  */
306 
307 #define uvm_lock_pageq()	simple_lock(&uvm.pageqlock)
308 #define uvm_unlock_pageq()	simple_unlock(&uvm.pageqlock)
309 #define uvm_lock_fpageq()	mtx_enter(&uvm.fpageqlock);
310 #define uvm_unlock_fpageq()	mtx_leave(&uvm.fpageqlock);
311 
312 #define uvm_pagehash(obj,off) \
313 	(((unsigned long)obj+(unsigned long)atop(off)) & uvm.page_hashmask)
314 
315 #define	UVM_PAGEZERO_TARGET	(uvmexp.free)
316 
317 #define VM_PAGE_TO_PHYS(entry)	((entry)->phys_addr)
318 
319 #define VM_PAGE_IS_FREE(entry)  ((entry)->pg_flags & PQ_FREE)
320 
321 #endif /* _KERNEL */
322 
323 #endif /* _UVM_UVM_PAGE_H_ */
324