xref: /openbsd-src/sys/uvm/uvm_page.h (revision 50b7afb2c2c0993b0894d4e34bf857cb13ed9c80)
1 /*	$OpenBSD: uvm_page.h,v 1.54 2014/07/11 16:35:40 jsg 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. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  *
37  *	@(#)vm_page.h   7.3 (Berkeley) 4/21/91
38  * from: Id: uvm_page.h,v 1.1.2.6 1998/02/04 02:31:42 chuck Exp
39  *
40  *
41  * Copyright (c) 1987, 1990 Carnegie-Mellon University.
42  * All rights reserved.
43  *
44  * Permission to use, copy, modify and distribute this software and
45  * its documentation is hereby granted, provided that both the copyright
46  * notice and this permission notice appear in all copies of the
47  * software, derivative works or modified versions, and any portions
48  * thereof, and that both notices appear in supporting documentation.
49  *
50  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
51  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
52  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
53  *
54  * Carnegie Mellon requests users of this software to return to
55  *
56  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
57  *  School of Computer Science
58  *  Carnegie Mellon University
59  *  Pittsburgh PA 15213-3890
60  *
61  * any improvements or extensions that they make and grant Carnegie the
62  * rights to redistribute these changes.
63  */
64 
65 #ifndef _UVM_UVM_PAGE_H_
66 #define _UVM_UVM_PAGE_H_
67 
68 /*
69  * uvm_page.h
70  */
71 
72 /*
73  *	Resident memory system definitions.
74  */
75 
76 /*
77  *	Management of resident (logical) pages.
78  *
79  *	A small structure is kept for each resident
80  *	page, indexed by page number.  Each structure
81  *	contains a list used for manipulating pages, and
82  *	a tree structure for in object/offset lookups
83  *
84  *	In addition, the structure contains the object
85  *	and offset to which this page belongs (for pageout),
86  *	and sundry status bits.
87  *
88  *	Fields in this structure are possibly locked by the lock on the page
89  *	queues (P).
90  */
91 
92 #include <uvm/uvm_extern.h>
93 
94 TAILQ_HEAD(pglist, vm_page);
95 
96 struct vm_page {
97 	TAILQ_ENTRY(vm_page)	pageq;		/* queue info for FIFO
98 						 * queue or free list (P) */
99 	RB_ENTRY(vm_page)	objt;		/* object tree */
100 
101 	struct vm_anon		*uanon;		/* anon (P) */
102 	struct uvm_object	*uobject;	/* object (P) */
103 	voff_t			offset;		/* offset into object (P) */
104 
105 	u_int			pg_flags;	/* object flags [P] */
106 
107 	u_int			pg_version;	/* version count */
108 	u_int			wire_count;	/* wired down map refs [P] */
109 
110 	u_int			loan_count;	/* number of active loans
111 						 * to read: [P]
112 						 * to modify: [P] */
113 	paddr_t			phys_addr;	/* physical address of page */
114 	psize_t			fpgsz;		/* free page range size */
115 
116 	struct vm_page_md	mdpage;		/* pmap-specific data */
117 
118 #if defined(UVM_PAGE_TRKOWN)
119 	/* debugging fields to track page ownership */
120 	pid_t			owner;		/* proc that set PG_BUSY */
121 	char			*owner_tag;	/* why it was set busy */
122 #endif
123 };
124 
125 /*
126  * These are the flags defined for vm_page.
127  *
128  * Note: PG_FILLED and PG_DIRTY are added for the filesystems.
129  */
130 
131 /*
132  * locking rules:
133  *   PQ_ ==> lock by page queue lock
134  *   PQ_FREE is locked by free queue lock and is mutex with all other PQs
135  *   pg_flags may only be changed using the atomic operations.
136  *
137  * PG_ZERO is used to indicate that a page has been pre-zero'd.  This flag
138  * is only set when the page is on no queues, and is cleared when the page
139  * is placed on the free list.
140  */
141 
142 #define	PG_BUSY		0x00000001	/* page is locked */
143 #define	PG_WANTED	0x00000002	/* someone is waiting for page */
144 #define	PG_TABLED	0x00000004	/* page is in VP table  */
145 #define	PG_CLEAN	0x00000008	/* page has not been modified */
146 #define PG_CLEANCHK	0x00000010	/* clean bit has been checked */
147 #define PG_RELEASED	0x00000020	/* page released while paging */
148 #define	PG_FAKE		0x00000040	/* page is not yet initialized */
149 #define PG_RDONLY	0x00000080	/* page must be mapped read-only */
150 #define PG_ZERO		0x00000100	/* page is pre-zero'd */
151 #define PG_DEV		0x00000200	/* page is in device space, lay off */
152 
153 #define PG_PAGER1	0x00001000	/* pager-specific flag */
154 #define PG_MASK		0x0000ffff
155 
156 #define PQ_FREE		0x00010000	/* page is on free list */
157 #define PQ_INACTIVE	0x00020000	/* page is in inactive list */
158 #define PQ_ACTIVE	0x00040000	/* page is in active list */
159 #define PQ_ANON		0x00100000	/* page is part of an anon, rather
160 					   than an uvm_object */
161 #define PQ_AOBJ		0x00200000	/* page is part of an anonymous
162 					   uvm_object */
163 #define PQ_SWAPBACKED	(PQ_ANON|PQ_AOBJ)
164 #define	PQ_ENCRYPT	0x00400000	/* page needs {en,de}cryption */
165 #define PQ_MASK		0x00ff0000
166 
167 #define PG_PMAP0	0x01000000	/* Used by some pmaps. */
168 #define PG_PMAP1	0x02000000	/* Used by some pmaps. */
169 #define PG_PMAP2	0x04000000	/* Used by some pmaps. */
170 #define PG_PMAP3	0x08000000	/* Used by some pmaps. */
171 #define PG_PMAP4	0x10000000	/* Used by some pmaps. */
172 #define PG_PMAP5	0x20000000	/* Used by some pmaps. */
173 #define PG_PMAPMASK	0x3f000000
174 
175 /*
176  * physical memory layout structure
177  *
178  * MD vmparam.h must #define:
179  *   VM_PHYSEG_MAX = max number of physical memory segments we support
180  *		   (if this is "1" then we revert to a "contig" case)
181  *   VM_PHYSSEG_STRAT: memory sort/search options (for VM_PHYSEG_MAX > 1)
182  * 	- VM_PSTRAT_RANDOM:   linear search (random order)
183  *	- VM_PSTRAT_BSEARCH:  binary search (sorted by address)
184  *	- VM_PSTRAT_BIGFIRST: linear search (sorted by largest segment first)
185  *      - others?
186  *   XXXCDC: eventually we should purge all left-over global variables...
187  */
188 #define VM_PSTRAT_RANDOM	1
189 #define VM_PSTRAT_BSEARCH	2
190 #define VM_PSTRAT_BIGFIRST	3
191 
192 /*
193  * vm_physmemseg: describes one segment of physical memory
194  */
195 struct vm_physseg {
196 	paddr_t	start;			/* PF# of first page in segment */
197 	paddr_t	end;			/* (PF# of last page in segment) + 1 */
198 	paddr_t	avail_start;		/* PF# of first free page in segment */
199 	paddr_t	avail_end;		/* (PF# of last free page in segment) +1  */
200 	struct	vm_page *pgs;		/* vm_page structures (from start) */
201 	struct	vm_page *lastpg;	/* vm_page structure for end */
202 };
203 
204 #ifdef _KERNEL
205 
206 /*
207  * globals
208  */
209 
210 extern boolean_t vm_page_zero_enable;
211 
212 /*
213  * physical memory config is stored in vm_physmem.
214  */
215 
216 extern struct vm_physseg vm_physmem[VM_PHYSSEG_MAX];
217 extern int vm_nphysseg;
218 
219 /*
220  * prototypes: the following prototypes define the interface to pages
221  */
222 
223 void		uvm_page_init(vaddr_t *, vaddr_t *);
224 #if defined(UVM_PAGE_TRKOWN)
225 void		uvm_page_own(struct vm_page *, char *);
226 #endif
227 #if !defined(PMAP_STEAL_MEMORY)
228 boolean_t	uvm_page_physget(paddr_t *);
229 #endif
230 void		uvm_pageidlezero(void);
231 
232 void		uvm_pageactivate(struct vm_page *);
233 vaddr_t		uvm_pageboot_alloc(vsize_t);
234 void		uvm_pagecopy(struct vm_page *, struct vm_page *);
235 void		uvm_pagedeactivate(struct vm_page *);
236 void		uvm_pagefree(struct vm_page *);
237 void		uvm_page_unbusy(struct vm_page **, int);
238 struct vm_page	*uvm_pagelookup(struct uvm_object *, voff_t);
239 void		uvm_pageunwire(struct vm_page *);
240 void		uvm_pagewait(struct vm_page *, int);
241 void		uvm_pagewake(struct vm_page *);
242 void		uvm_pagewire(struct vm_page *);
243 void		uvm_pagezero(struct vm_page *);
244 void		uvm_pagealloc_pg(struct vm_page *, struct uvm_object *,
245 		    voff_t, struct vm_anon *);
246 
247 struct uvm_constraint_range; /* XXX move to uvm_extern.h? */
248 psize_t		uvm_pagecount(struct uvm_constraint_range*);
249 
250 #if  VM_PHYSSEG_MAX == 1
251 /*
252  * Inline functions for archs like the vax where function calls are expensive.
253  */
254 /*
255  * vm_physseg_find: find vm_physseg structure that belongs to a PA
256  */
257 static __inline int
258 vm_physseg_find(paddr_t pframe, int *offp)
259 {
260 	/* 'contig' case */
261 	if (pframe >= vm_physmem[0].start && pframe < vm_physmem[0].end) {
262 		if (offp)
263 			*offp = pframe - vm_physmem[0].start;
264 		return(0);
265 	}
266 	return(-1);
267 }
268 
269 /*
270  * PHYS_TO_VM_PAGE: find vm_page for a PA.   used by MI code to get vm_pages
271  * back from an I/O mapping (ugh!).   used in some MD code as well.
272  */
273 static __inline struct vm_page *
274 PHYS_TO_VM_PAGE(paddr_t pa)
275 {
276 	paddr_t pf = atop(pa);
277 	int	off;
278 	int	psi;
279 
280 	psi = vm_physseg_find(pf, &off);
281 
282 	return ((psi == -1) ? NULL : &vm_physmem[psi].pgs[off]);
283 }
284 #else
285 /* if VM_PHYSSEG_MAX > 1 they're not inline, they're in uvm_page.c. */
286 struct vm_page	*PHYS_TO_VM_PAGE(paddr_t);
287 int		vm_physseg_find(paddr_t, int *);
288 #endif
289 
290 /*
291  * macros
292  */
293 
294 #define uvm_lock_pageq()	/* lock */
295 #define uvm_unlock_pageq()	/* unlock */
296 #define uvm_lock_fpageq()	mtx_enter(&uvm.fpageqlock);
297 #define uvm_unlock_fpageq()	mtx_leave(&uvm.fpageqlock);
298 
299 #define	UVM_PAGEZERO_TARGET	(uvmexp.free)
300 
301 #define VM_PAGE_TO_PHYS(entry)	((entry)->phys_addr)
302 
303 #define VM_PAGE_IS_FREE(entry)  ((entry)->pg_flags & PQ_FREE)
304 
305 #define	PADDR_IS_DMA_REACHABLE(paddr)	\
306 	(dma_constraint.ucr_low <= paddr && dma_constraint.ucr_high > paddr)
307 
308 #endif /* _KERNEL */
309 
310 #endif /* _UVM_UVM_PAGE_H_ */
311