xref: /freebsd/sys/vm/vm_page.h (revision a8445737e740901f5f2c8d24c12ef7fc8b00134e)
1 /*
2  * Copyright (c) 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * The Mach Operating System project at Carnegie-Mellon University.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	from: @(#)vm_page.h	8.2 (Berkeley) 12/13/93
37  *
38  *
39  * Copyright (c) 1987, 1990 Carnegie-Mellon University.
40  * All rights reserved.
41  *
42  * Authors: Avadis Tevanian, Jr., Michael Wayne Young
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  * $Id: vm_page.h,v 1.45 1998/09/01 17:12:19 wollman Exp $
65  */
66 
67 /*
68  *	Resident memory system definitions.
69  */
70 
71 #ifndef	_VM_PAGE_
72 #define	_VM_PAGE_
73 
74 #include "opt_vmpage.h"
75 
76 #include <vm/pmap.h>
77 #include <machine/atomic.h>
78 
79 /*
80  *	Management of resident (logical) pages.
81  *
82  *	A small structure is kept for each resident
83  *	page, indexed by page number.  Each structure
84  *	is an element of several lists:
85  *
86  *		A hash table bucket used to quickly
87  *		perform object/offset lookups
88  *
89  *		A list of all pages for a given object,
90  *		so they can be quickly deactivated at
91  *		time of deallocation.
92  *
93  *		An ordered list of pages due for pageout.
94  *
95  *	In addition, the structure contains the object
96  *	and offset to which this page belongs (for pageout),
97  *	and sundry status bits.
98  *
99  *	Fields in this structure are locked either by the lock on the
100  *	object that the page belongs to (O) or by the lock on the page
101  *	queues (P).
102  */
103 
104 TAILQ_HEAD(pglist, vm_page);
105 
106 struct vm_page {
107 	TAILQ_ENTRY(vm_page) pageq;	/* queue info for FIFO queue or free list (P) */
108 	TAILQ_ENTRY(vm_page) hashq;	/* hash table links (O) */
109 	TAILQ_ENTRY(vm_page) listq;	/* pages in same object (O) */
110 
111 	vm_object_t object;		/* which object am I in (O,P) */
112 	vm_pindex_t pindex;		/* offset into object (O,P) */
113 	vm_offset_t phys_addr;		/* physical address of page */
114 	u_short	queue;			/* page queue index */
115 	u_short	flags,			/* see below */
116 		pc;			/* page color */
117 	u_short wire_count;		/* wired down maps refs (P) */
118 	short hold_count;		/* page hold count */
119 	u_char	act_count;		/* page usage count */
120 	u_char	busy;			/* page busy count */
121 	/* NOTE that these must support one bit per DEV_BSIZE in a page!!! */
122 	/* so, on normal X86 kernels, they must be at least 8 bits wide */
123 #if PAGE_SIZE == 4096
124 	u_char	valid;			/* map of valid DEV_BSIZE chunks */
125 	u_char	dirty;			/* map of dirty DEV_BSIZE chunks */
126 #elif PAGE_SIZE == 8192
127 	u_short	valid;			/* map of valid DEV_BSIZE chunks */
128 	u_short	dirty;			/* map of dirty DEV_BSIZE chunks */
129 #endif
130 };
131 
132 /*
133  * Page coloring parameters
134  */
135 /* Each of PQ_FREE, PQ_ZERO and PQ_CACHE have PQ_HASH_SIZE entries */
136 
137 /* Define one of the following */
138 #if defined(PQ_HUGECACHE)
139 #define PQ_PRIME1 31	/* Prime number somewhat less than PQ_HASH_SIZE */
140 #define PQ_PRIME2 23	/* Prime number somewhat less than PQ_HASH_SIZE */
141 #define PQ_PRIME3 17	/* Prime number somewhat less than PQ_HASH_SIZE */
142 #define PQ_L2_SIZE 256	/* A number of colors opt for 1M cache */
143 #define PQ_L1_SIZE 4	/* Four page L1 cache */
144 #endif
145 
146 /* Define one of the following */
147 #if defined(PQ_LARGECACHE)
148 #define PQ_PRIME1 31	/* Prime number somewhat less than PQ_HASH_SIZE */
149 #define PQ_PRIME2 23	/* Prime number somewhat less than PQ_HASH_SIZE */
150 #define PQ_PRIME3 17	/* Prime number somewhat less than PQ_HASH_SIZE */
151 #define PQ_L2_SIZE 128	/* A number of colors opt for 512K cache */
152 #define PQ_L1_SIZE 4	/* Four page L1 cache (for PII) */
153 #endif
154 
155 
156 /*
157  * Use 'options PQ_NOOPT' to disable page coloring
158  */
159 #if defined(PQ_NOOPT)
160 #define PQ_PRIME1 1
161 #define PQ_PRIME2 1
162 #define PQ_PRIME3 1
163 #define PQ_L2_SIZE 1
164 #define PQ_L1_SIZE 1
165 #endif
166 
167 #if defined(PQ_NORMALCACHE)
168 #define PQ_PRIME1 5	/* Prime number somewhat less than PQ_HASH_SIZE */
169 #define PQ_PRIME2 3	/* Prime number somewhat less than PQ_HASH_SIZE */
170 #define PQ_PRIME3 11	/* Prime number somewhat less than PQ_HASH_SIZE */
171 #define PQ_L2_SIZE 16	/* A reasonable number of colors (opt for 64K cache) */
172 #define PQ_L1_SIZE 2	/* Two page L1 cache */
173 #endif
174 
175 #if defined(PQ_MEDIUMCACHE) || !defined(PQ_L2_SIZE)
176 #define PQ_PRIME1 13	/* Prime number somewhat less than PQ_HASH_SIZE */
177 #define PQ_PRIME2 7	/* Prime number somewhat less than PQ_HASH_SIZE */
178 #define PQ_PRIME3 5	/* Prime number somewhat less than PQ_HASH_SIZE */
179 #define PQ_L2_SIZE 64	/* A number of colors opt for 256K cache */
180 #define PQ_L1_SIZE 2	/* Two page L1 cache */
181 #endif
182 
183 #define PQ_L2_MASK (PQ_L2_SIZE - 1)
184 
185 #define PQ_NONE 0
186 #define PQ_FREE	1
187 #define PQ_ZERO (1 + PQ_L2_SIZE)
188 #define PQ_INACTIVE (1 + 2*PQ_L2_SIZE)
189 #define PQ_ACTIVE (2 + 2*PQ_L2_SIZE)
190 #define PQ_CACHE (3 + 2*PQ_L2_SIZE)
191 #define PQ_COUNT (3 + 3*PQ_L2_SIZE)
192 
193 extern struct vpgqueues {
194 	struct pglist *pl;
195 	int	*cnt;
196 	int	*lcnt;
197 } vm_page_queues[PQ_COUNT];
198 
199 /*
200  * These are the flags defined for vm_page.
201  *
202  * Note: PG_FILLED and PG_DIRTY are added for the filesystems.
203  */
204 #define	PG_BUSY		0x01		/* page is in transit (O) */
205 #define	PG_WANTED	0x02		/* someone is waiting for page (O) */
206 #define	PG_TABLED	0x04		/* page is in an object (O) */
207 #define	PG_FICTITIOUS	0x08		/* physical page doesn't exist (O) */
208 #define	PG_WRITEABLE	0x10		/* page is mapped writeable */
209 #define PG_MAPPED	0x20		/* page is mapped */
210 #define	PG_ZERO		0x40		/* page is zeroed */
211 #define PG_REFERENCED	0x80		/* page has been referenced */
212 #define PG_CLEANCHK	0x100		/* page will be checked for cleaning */
213 
214 /*
215  * Misc constants.
216  */
217 
218 #define ACT_DECLINE		1
219 #define ACT_ADVANCE		3
220 #define ACT_INIT		5
221 #define ACT_MAX			64
222 #define PFCLUSTER_BEHIND	3
223 #define PFCLUSTER_AHEAD		3
224 
225 #ifdef KERNEL
226 /*
227  * Each pageable resident page falls into one of four lists:
228  *
229  *	free
230  *		Available for allocation now.
231  *
232  * The following are all LRU sorted:
233  *
234  *	cache
235  *		Almost available for allocation. Still in an
236  *		object, but clean and immediately freeable at
237  *		non-interrupt times.
238  *
239  *	inactive
240  *		Low activity, candidates for reclamation.
241  *		This is the list of pages that should be
242  *		paged out next.
243  *
244  *	active
245  *		Pages that are "active" i.e. they have been
246  *		recently referenced.
247  *
248  *	zero
249  *		Pages that are really free and have been pre-zeroed
250  *
251  */
252 
253 extern struct pglist vm_page_queue_free[PQ_L2_SIZE];/* memory free queue */
254 extern struct pglist vm_page_queue_zero[PQ_L2_SIZE];/* zeroed memory free queue */
255 extern struct pglist vm_page_queue_active;	/* active memory queue */
256 extern struct pglist vm_page_queue_inactive;	/* inactive memory queue */
257 extern struct pglist vm_page_queue_cache[PQ_L2_SIZE];/* cache memory queue */
258 
259 extern int vm_page_zero_count;
260 
261 extern vm_page_t vm_page_array;		/* First resident page in table */
262 extern long first_page;			/* first physical page number */
263 
264  /* ... represented in vm_page_array */
265 extern long last_page;			/* last physical page number */
266 
267  /* ... represented in vm_page_array */
268  /* [INCLUSIVE] */
269 extern vm_offset_t first_phys_addr;	/* physical address for first_page */
270 extern vm_offset_t last_phys_addr;	/* physical address for last_page */
271 
272 #define VM_PAGE_TO_PHYS(entry)	((entry)->phys_addr)
273 
274 #define IS_VM_PHYSADDR(pa) \
275 		((pa) >= first_phys_addr && (pa) <= last_phys_addr)
276 
277 #define PHYS_TO_VM_PAGE(pa) \
278 		(&vm_page_array[atop(pa) - first_page ])
279 
280 /*
281  *	Functions implemented as macros
282  */
283 
284 static __inline void
285 vm_page_flag_set(vm_page_t m, unsigned int bits)
286 {
287 	atomic_set_short(&(m)->flags, bits);
288 }
289 
290 static __inline void
291 vm_page_flag_clear(vm_page_t m, unsigned int bits)
292 {
293 	atomic_clear_short(&(m)->flags, bits);
294 }
295 
296 #if 0
297 static __inline void
298 vm_page_assert_wait(vm_page_t m, int interruptible)
299 {
300 	vm_page_flag_set(m, PG_WANTED);
301 	assert_wait((int) m, interruptible);
302 }
303 #endif
304 
305 static __inline void
306 vm_page_busy(vm_page_t m)
307 {
308 	vm_page_flag_set(m, PG_BUSY);
309 }
310 
311 static __inline void
312 vm_page_wakeup(vm_page_t m)
313 {
314 	vm_page_flag_clear(m, PG_BUSY);
315 	if (m->flags & PG_WANTED) {
316 		vm_page_flag_clear(m, PG_WANTED);
317 		wakeup(m);
318 	}
319 }
320 
321 static __inline void
322 vm_page_io_start(vm_page_t m)
323 {
324 	atomic_add_char(&(m)->busy, 1);
325 }
326 
327 static __inline void
328 vm_page_io_finish(vm_page_t m)
329 {
330 	atomic_subtract_char(&m->busy, 1);
331 	if ((m->flags & PG_WANTED) && m->busy == 0) {
332 		vm_page_flag_clear(m, PG_WANTED);
333 		wakeup(m);
334 	}
335 }
336 
337 
338 #if PAGE_SIZE == 4096
339 #define VM_PAGE_BITS_ALL 0xff
340 #endif
341 
342 #if PAGE_SIZE == 8192
343 #define VM_PAGE_BITS_ALL 0xffff
344 #endif
345 
346 #define VM_ALLOC_NORMAL		0
347 #define VM_ALLOC_INTERRUPT	1
348 #define VM_ALLOC_SYSTEM		2
349 #define	VM_ALLOC_ZERO		3
350 #define	VM_ALLOC_RETRY		0x80
351 
352 void vm_page_activate __P((vm_page_t));
353 vm_page_t vm_page_alloc __P((vm_object_t, vm_pindex_t, int));
354 vm_page_t vm_page_grab __P((vm_object_t, vm_pindex_t, int));
355 void vm_page_cache __P((register vm_page_t));
356 static __inline void vm_page_copy __P((vm_page_t, vm_page_t));
357 void vm_page_deactivate __P((vm_page_t));
358 void vm_page_free __P((vm_page_t));
359 void vm_page_free_zero __P((vm_page_t));
360 void vm_page_insert __P((vm_page_t, vm_object_t, vm_pindex_t));
361 vm_page_t vm_page_lookup __P((vm_object_t, vm_pindex_t));
362 void vm_page_remove __P((vm_page_t));
363 void vm_page_rename __P((vm_page_t, vm_object_t, vm_pindex_t));
364 vm_offset_t vm_page_startup __P((vm_offset_t, vm_offset_t, vm_offset_t));
365 void vm_page_unwire __P((vm_page_t));
366 void vm_page_wire __P((vm_page_t));
367 void vm_page_unqueue __P((vm_page_t));
368 void vm_page_unqueue_nowakeup __P((vm_page_t));
369 void vm_page_set_validclean __P((vm_page_t, int, int));
370 void vm_page_set_invalid __P((vm_page_t, int, int));
371 static __inline boolean_t vm_page_zero_fill __P((vm_page_t));
372 int vm_page_is_valid __P((vm_page_t, int, int));
373 void vm_page_test_dirty __P((vm_page_t));
374 int vm_page_bits __P((int, int));
375 vm_page_t vm_page_list_find __P((int, int));
376 int vm_page_queue_index __P((vm_offset_t, int));
377 vm_page_t vm_page_select __P((vm_object_t, vm_pindex_t, int));
378 int vm_page_sleep(vm_page_t m, char *msg, char *busy);
379 
380 /*
381  * Keep page from being freed by the page daemon
382  * much of the same effect as wiring, except much lower
383  * overhead and should be used only for *very* temporary
384  * holding ("wiring").
385  */
386 static __inline void
387 vm_page_hold(vm_page_t mem)
388 {
389 	mem->hold_count++;
390 }
391 
392 static __inline void
393 vm_page_unhold(vm_page_t mem)
394 {
395 #ifdef DIAGNOSTIC
396 	if (--mem->hold_count < 0)
397 		panic("vm_page_unhold: hold count < 0!!!");
398 #else
399 	--mem->hold_count;
400 #endif
401 }
402 
403 static __inline void
404 vm_page_protect(vm_page_t mem, int prot)
405 {
406 	if (prot == VM_PROT_NONE) {
407 		if (mem->flags & (PG_WRITEABLE|PG_MAPPED)) {
408 			pmap_page_protect(VM_PAGE_TO_PHYS(mem), VM_PROT_NONE);
409 			vm_page_flag_clear(mem, PG_WRITEABLE|PG_MAPPED);
410 		}
411 	} else if ((prot == VM_PROT_READ) && (mem->flags & PG_WRITEABLE)) {
412 		pmap_page_protect(VM_PAGE_TO_PHYS(mem), VM_PROT_READ);
413 		vm_page_flag_clear(mem, PG_WRITEABLE);
414 	}
415 }
416 
417 /*
418  *	vm_page_zero_fill:
419  *
420  *	Zero-fill the specified page.
421  *	Written as a standard pagein routine, to
422  *	be used by the zero-fill object.
423  */
424 static __inline boolean_t
425 vm_page_zero_fill(m)
426 	vm_page_t m;
427 {
428 	pmap_zero_page(VM_PAGE_TO_PHYS(m));
429 	return (TRUE);
430 }
431 
432 /*
433  *	vm_page_copy:
434  *
435  *	Copy one page to another
436  */
437 static __inline void
438 vm_page_copy(src_m, dest_m)
439 	vm_page_t src_m;
440 	vm_page_t dest_m;
441 {
442 	pmap_copy_page(VM_PAGE_TO_PHYS(src_m), VM_PAGE_TO_PHYS(dest_m));
443 	dest_m->valid = VM_PAGE_BITS_ALL;
444 }
445 
446 #endif				/* KERNEL */
447 #endif				/* !_VM_PAGE_ */
448