xref: /freebsd/sys/vm/vm_phys.c (revision ddd5b8e9b4d8957fce018c520657cdfa4ecffad3)
1 /*-
2  * Copyright (c) 2002-2006 Rice University
3  * Copyright (c) 2007 Alan L. Cox <alc@cs.rice.edu>
4  * All rights reserved.
5  *
6  * This software was developed for the FreeBSD Project by Alan L. Cox,
7  * Olivier Crameri, Peter Druschel, Sitaram Iyer, and Juan Navarro.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21  * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT
22  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
24  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
25  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
26  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
28  * WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  *	Physical memory system implementation
34  *
35  * Any external functions defined by this module are only to be used by the
36  * virtual memory system.
37  */
38 
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 #include "opt_ddb.h"
43 #include "opt_vm.h"
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/lock.h>
48 #include <sys/kernel.h>
49 #include <sys/malloc.h>
50 #include <sys/mutex.h>
51 #include <sys/queue.h>
52 #include <sys/sbuf.h>
53 #include <sys/sysctl.h>
54 #include <sys/vmmeter.h>
55 
56 #include <ddb/ddb.h>
57 
58 #include <vm/vm.h>
59 #include <vm/vm_param.h>
60 #include <vm/vm_kern.h>
61 #include <vm/vm_object.h>
62 #include <vm/vm_page.h>
63 #include <vm/vm_phys.h>
64 
65 /*
66  * VM_FREELIST_DEFAULT is split into VM_NDOMAIN lists, one for each
67  * domain.  These extra lists are stored at the end of the regular
68  * free lists starting with VM_NFREELIST.
69  */
70 #define VM_RAW_NFREELIST	(VM_NFREELIST + VM_NDOMAIN - 1)
71 
72 struct vm_freelist {
73 	struct pglist pl;
74 	int lcnt;
75 };
76 
77 struct vm_phys_seg {
78 	vm_paddr_t	start;
79 	vm_paddr_t	end;
80 	vm_page_t	first_page;
81 	int		domain;
82 	struct vm_freelist (*free_queues)[VM_NFREEPOOL][VM_NFREEORDER];
83 };
84 
85 struct mem_affinity *mem_affinity;
86 
87 static struct vm_phys_seg vm_phys_segs[VM_PHYSSEG_MAX];
88 
89 static int vm_phys_nsegs;
90 
91 #define VM_PHYS_FICTITIOUS_NSEGS	8
92 static struct vm_phys_fictitious_seg {
93 	vm_paddr_t	start;
94 	vm_paddr_t	end;
95 	vm_page_t	first_page;
96 } vm_phys_fictitious_segs[VM_PHYS_FICTITIOUS_NSEGS];
97 static struct mtx vm_phys_fictitious_reg_mtx;
98 MALLOC_DEFINE(M_FICT_PAGES, "", "");
99 
100 static struct vm_freelist
101     vm_phys_free_queues[VM_RAW_NFREELIST][VM_NFREEPOOL][VM_NFREEORDER];
102 static struct vm_freelist
103 (*vm_phys_lookup_lists[VM_NDOMAIN][VM_RAW_NFREELIST])[VM_NFREEPOOL][VM_NFREEORDER];
104 
105 static int vm_nfreelists = VM_FREELIST_DEFAULT + 1;
106 
107 static int cnt_prezero;
108 SYSCTL_INT(_vm_stats_misc, OID_AUTO, cnt_prezero, CTLFLAG_RD,
109     &cnt_prezero, 0, "The number of physical pages prezeroed at idle time");
110 
111 static int sysctl_vm_phys_free(SYSCTL_HANDLER_ARGS);
112 SYSCTL_OID(_vm, OID_AUTO, phys_free, CTLTYPE_STRING | CTLFLAG_RD,
113     NULL, 0, sysctl_vm_phys_free, "A", "Phys Free Info");
114 
115 static int sysctl_vm_phys_segs(SYSCTL_HANDLER_ARGS);
116 SYSCTL_OID(_vm, OID_AUTO, phys_segs, CTLTYPE_STRING | CTLFLAG_RD,
117     NULL, 0, sysctl_vm_phys_segs, "A", "Phys Seg Info");
118 
119 #if VM_NDOMAIN > 1
120 static int sysctl_vm_phys_lookup_lists(SYSCTL_HANDLER_ARGS);
121 SYSCTL_OID(_vm, OID_AUTO, phys_lookup_lists, CTLTYPE_STRING | CTLFLAG_RD,
122     NULL, 0, sysctl_vm_phys_lookup_lists, "A", "Phys Lookup Lists");
123 #endif
124 
125 static void _vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int flind,
126     int domain);
127 static void vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int flind);
128 static int vm_phys_paddr_to_segind(vm_paddr_t pa);
129 static void vm_phys_split_pages(vm_page_t m, int oind, struct vm_freelist *fl,
130     int order);
131 
132 /*
133  * Outputs the state of the physical memory allocator, specifically,
134  * the amount of physical memory in each free list.
135  */
136 static int
137 sysctl_vm_phys_free(SYSCTL_HANDLER_ARGS)
138 {
139 	struct sbuf sbuf;
140 	struct vm_freelist *fl;
141 	int error, flind, oind, pind;
142 
143 	error = sysctl_wire_old_buffer(req, 0);
144 	if (error != 0)
145 		return (error);
146 	sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
147 	for (flind = 0; flind < vm_nfreelists; flind++) {
148 		sbuf_printf(&sbuf, "\nFREE LIST %d:\n"
149 		    "\n  ORDER (SIZE)  |  NUMBER"
150 		    "\n              ", flind);
151 		for (pind = 0; pind < VM_NFREEPOOL; pind++)
152 			sbuf_printf(&sbuf, "  |  POOL %d", pind);
153 		sbuf_printf(&sbuf, "\n--            ");
154 		for (pind = 0; pind < VM_NFREEPOOL; pind++)
155 			sbuf_printf(&sbuf, "-- --      ");
156 		sbuf_printf(&sbuf, "--\n");
157 		for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
158 			sbuf_printf(&sbuf, "  %2d (%6dK)", oind,
159 			    1 << (PAGE_SHIFT - 10 + oind));
160 			for (pind = 0; pind < VM_NFREEPOOL; pind++) {
161 				fl = vm_phys_free_queues[flind][pind];
162 				sbuf_printf(&sbuf, "  |  %6d", fl[oind].lcnt);
163 			}
164 			sbuf_printf(&sbuf, "\n");
165 		}
166 	}
167 	error = sbuf_finish(&sbuf);
168 	sbuf_delete(&sbuf);
169 	return (error);
170 }
171 
172 /*
173  * Outputs the set of physical memory segments.
174  */
175 static int
176 sysctl_vm_phys_segs(SYSCTL_HANDLER_ARGS)
177 {
178 	struct sbuf sbuf;
179 	struct vm_phys_seg *seg;
180 	int error, segind;
181 
182 	error = sysctl_wire_old_buffer(req, 0);
183 	if (error != 0)
184 		return (error);
185 	sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
186 	for (segind = 0; segind < vm_phys_nsegs; segind++) {
187 		sbuf_printf(&sbuf, "\nSEGMENT %d:\n\n", segind);
188 		seg = &vm_phys_segs[segind];
189 		sbuf_printf(&sbuf, "start:     %#jx\n",
190 		    (uintmax_t)seg->start);
191 		sbuf_printf(&sbuf, "end:       %#jx\n",
192 		    (uintmax_t)seg->end);
193 		sbuf_printf(&sbuf, "domain:    %d\n", seg->domain);
194 		sbuf_printf(&sbuf, "free list: %p\n", seg->free_queues);
195 	}
196 	error = sbuf_finish(&sbuf);
197 	sbuf_delete(&sbuf);
198 	return (error);
199 }
200 
201 #if VM_NDOMAIN > 1
202 /*
203  * Outputs the set of free list lookup lists.
204  */
205 static int
206 sysctl_vm_phys_lookup_lists(SYSCTL_HANDLER_ARGS)
207 {
208 	struct sbuf sbuf;
209 	int domain, error, flind, ndomains;
210 
211 	error = sysctl_wire_old_buffer(req, 0);
212 	if (error != 0)
213 		return (error);
214 	sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
215 	ndomains = vm_nfreelists - VM_NFREELIST + 1;
216 	for (domain = 0; domain < ndomains; domain++) {
217 		sbuf_printf(&sbuf, "\nDOMAIN %d:\n\n", domain);
218 		for (flind = 0; flind < vm_nfreelists; flind++)
219 			sbuf_printf(&sbuf, "  [%d]:\t%p\n", flind,
220 			    vm_phys_lookup_lists[domain][flind]);
221 	}
222 	error = sbuf_finish(&sbuf);
223 	sbuf_delete(&sbuf);
224 	return (error);
225 }
226 #endif
227 
228 /*
229  * Create a physical memory segment.
230  */
231 static void
232 _vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int flind, int domain)
233 {
234 	struct vm_phys_seg *seg;
235 #ifdef VM_PHYSSEG_SPARSE
236 	long pages;
237 	int segind;
238 
239 	pages = 0;
240 	for (segind = 0; segind < vm_phys_nsegs; segind++) {
241 		seg = &vm_phys_segs[segind];
242 		pages += atop(seg->end - seg->start);
243 	}
244 #endif
245 	KASSERT(vm_phys_nsegs < VM_PHYSSEG_MAX,
246 	    ("vm_phys_create_seg: increase VM_PHYSSEG_MAX"));
247 	seg = &vm_phys_segs[vm_phys_nsegs++];
248 	seg->start = start;
249 	seg->end = end;
250 	seg->domain = domain;
251 #ifdef VM_PHYSSEG_SPARSE
252 	seg->first_page = &vm_page_array[pages];
253 #else
254 	seg->first_page = PHYS_TO_VM_PAGE(start);
255 #endif
256 #if VM_NDOMAIN > 1
257 	if (flind == VM_FREELIST_DEFAULT && domain != 0) {
258 		flind = VM_NFREELIST + (domain - 1);
259 		if (flind >= vm_nfreelists)
260 			vm_nfreelists = flind + 1;
261 	}
262 #endif
263 	seg->free_queues = &vm_phys_free_queues[flind];
264 }
265 
266 static void
267 vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int flind)
268 {
269 	int i;
270 
271 	if (mem_affinity == NULL) {
272 		_vm_phys_create_seg(start, end, flind, 0);
273 		return;
274 	}
275 
276 	for (i = 0;; i++) {
277 		if (mem_affinity[i].end == 0)
278 			panic("Reached end of affinity info");
279 		if (mem_affinity[i].end <= start)
280 			continue;
281 		if (mem_affinity[i].start > start)
282 			panic("No affinity info for start %jx",
283 			    (uintmax_t)start);
284 		if (mem_affinity[i].end >= end) {
285 			_vm_phys_create_seg(start, end, flind,
286 			    mem_affinity[i].domain);
287 			break;
288 		}
289 		_vm_phys_create_seg(start, mem_affinity[i].end, flind,
290 		    mem_affinity[i].domain);
291 		start = mem_affinity[i].end;
292 	}
293 }
294 
295 /*
296  * Initialize the physical memory allocator.
297  */
298 void
299 vm_phys_init(void)
300 {
301 	struct vm_freelist *fl;
302 	int flind, i, oind, pind;
303 #if VM_NDOMAIN > 1
304 	int ndomains, j;
305 #endif
306 
307 	for (i = 0; phys_avail[i + 1] != 0; i += 2) {
308 #ifdef	VM_FREELIST_ISADMA
309 		if (phys_avail[i] < 16777216) {
310 			if (phys_avail[i + 1] > 16777216) {
311 				vm_phys_create_seg(phys_avail[i], 16777216,
312 				    VM_FREELIST_ISADMA);
313 				vm_phys_create_seg(16777216, phys_avail[i + 1],
314 				    VM_FREELIST_DEFAULT);
315 			} else {
316 				vm_phys_create_seg(phys_avail[i],
317 				    phys_avail[i + 1], VM_FREELIST_ISADMA);
318 			}
319 			if (VM_FREELIST_ISADMA >= vm_nfreelists)
320 				vm_nfreelists = VM_FREELIST_ISADMA + 1;
321 		} else
322 #endif
323 #ifdef	VM_FREELIST_HIGHMEM
324 		if (phys_avail[i + 1] > VM_HIGHMEM_ADDRESS) {
325 			if (phys_avail[i] < VM_HIGHMEM_ADDRESS) {
326 				vm_phys_create_seg(phys_avail[i],
327 				    VM_HIGHMEM_ADDRESS, VM_FREELIST_DEFAULT);
328 				vm_phys_create_seg(VM_HIGHMEM_ADDRESS,
329 				    phys_avail[i + 1], VM_FREELIST_HIGHMEM);
330 			} else {
331 				vm_phys_create_seg(phys_avail[i],
332 				    phys_avail[i + 1], VM_FREELIST_HIGHMEM);
333 			}
334 			if (VM_FREELIST_HIGHMEM >= vm_nfreelists)
335 				vm_nfreelists = VM_FREELIST_HIGHMEM + 1;
336 		} else
337 #endif
338 		vm_phys_create_seg(phys_avail[i], phys_avail[i + 1],
339 		    VM_FREELIST_DEFAULT);
340 	}
341 	for (flind = 0; flind < vm_nfreelists; flind++) {
342 		for (pind = 0; pind < VM_NFREEPOOL; pind++) {
343 			fl = vm_phys_free_queues[flind][pind];
344 			for (oind = 0; oind < VM_NFREEORDER; oind++)
345 				TAILQ_INIT(&fl[oind].pl);
346 		}
347 	}
348 #if VM_NDOMAIN > 1
349 	/*
350 	 * Build a free list lookup list for each domain.  All of the
351 	 * memory domain lists are inserted at the VM_FREELIST_DEFAULT
352 	 * index in a round-robin order starting with the current
353 	 * domain.
354 	 */
355 	ndomains = vm_nfreelists - VM_NFREELIST + 1;
356 	for (flind = 0; flind < VM_FREELIST_DEFAULT; flind++)
357 		for (i = 0; i < ndomains; i++)
358 			vm_phys_lookup_lists[i][flind] =
359 			    &vm_phys_free_queues[flind];
360 	for (i = 0; i < ndomains; i++)
361 		for (j = 0; j < ndomains; j++) {
362 			flind = (i + j) % ndomains;
363 			if (flind == 0)
364 				flind = VM_FREELIST_DEFAULT;
365 			else
366 				flind += VM_NFREELIST - 1;
367 			vm_phys_lookup_lists[i][VM_FREELIST_DEFAULT + j] =
368 			    &vm_phys_free_queues[flind];
369 		}
370 	for (flind = VM_FREELIST_DEFAULT + 1; flind < VM_NFREELIST;
371 	     flind++)
372 		for (i = 0; i < ndomains; i++)
373 			vm_phys_lookup_lists[i][flind + ndomains - 1] =
374 			    &vm_phys_free_queues[flind];
375 #else
376 	for (flind = 0; flind < vm_nfreelists; flind++)
377 		vm_phys_lookup_lists[0][flind] = &vm_phys_free_queues[flind];
378 #endif
379 
380 	mtx_init(&vm_phys_fictitious_reg_mtx, "vmfctr", NULL, MTX_DEF);
381 }
382 
383 /*
384  * Split a contiguous, power of two-sized set of physical pages.
385  */
386 static __inline void
387 vm_phys_split_pages(vm_page_t m, int oind, struct vm_freelist *fl, int order)
388 {
389 	vm_page_t m_buddy;
390 
391 	while (oind > order) {
392 		oind--;
393 		m_buddy = &m[1 << oind];
394 		KASSERT(m_buddy->order == VM_NFREEORDER,
395 		    ("vm_phys_split_pages: page %p has unexpected order %d",
396 		    m_buddy, m_buddy->order));
397 		m_buddy->order = oind;
398 		TAILQ_INSERT_HEAD(&fl[oind].pl, m_buddy, pageq);
399 		fl[oind].lcnt++;
400         }
401 }
402 
403 /*
404  * Initialize a physical page and add it to the free lists.
405  */
406 void
407 vm_phys_add_page(vm_paddr_t pa)
408 {
409 	vm_page_t m;
410 
411 	cnt.v_page_count++;
412 	m = vm_phys_paddr_to_vm_page(pa);
413 	m->phys_addr = pa;
414 	m->queue = PQ_NONE;
415 	m->segind = vm_phys_paddr_to_segind(pa);
416 	m->flags = PG_FREE;
417 	KASSERT(m->order == VM_NFREEORDER,
418 	    ("vm_phys_add_page: page %p has unexpected order %d",
419 	    m, m->order));
420 	m->pool = VM_FREEPOOL_DEFAULT;
421 	pmap_page_init(m);
422 	mtx_lock(&vm_page_queue_free_mtx);
423 	cnt.v_free_count++;
424 	vm_phys_free_pages(m, 0);
425 	mtx_unlock(&vm_page_queue_free_mtx);
426 }
427 
428 /*
429  * Allocate a contiguous, power of two-sized set of physical pages
430  * from the free lists.
431  *
432  * The free page queues must be locked.
433  */
434 vm_page_t
435 vm_phys_alloc_pages(int pool, int order)
436 {
437 	vm_page_t m;
438 	int flind;
439 
440 	for (flind = 0; flind < vm_nfreelists; flind++) {
441 		m = vm_phys_alloc_freelist_pages(flind, pool, order);
442 		if (m != NULL)
443 			return (m);
444 	}
445 	return (NULL);
446 }
447 
448 /*
449  * Find and dequeue a free page on the given free list, with the
450  * specified pool and order
451  */
452 vm_page_t
453 vm_phys_alloc_freelist_pages(int flind, int pool, int order)
454 {
455 	struct vm_freelist *fl;
456 	struct vm_freelist *alt;
457 	int domain, oind, pind;
458 	vm_page_t m;
459 
460 	KASSERT(flind < VM_NFREELIST,
461 	    ("vm_phys_alloc_freelist_pages: freelist %d is out of range", flind));
462 	KASSERT(pool < VM_NFREEPOOL,
463 	    ("vm_phys_alloc_freelist_pages: pool %d is out of range", pool));
464 	KASSERT(order < VM_NFREEORDER,
465 	    ("vm_phys_alloc_freelist_pages: order %d is out of range", order));
466 
467 #if VM_NDOMAIN > 1
468 	domain = PCPU_GET(domain);
469 #else
470 	domain = 0;
471 #endif
472 	mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
473 	fl = (*vm_phys_lookup_lists[domain][flind])[pool];
474 	for (oind = order; oind < VM_NFREEORDER; oind++) {
475 		m = TAILQ_FIRST(&fl[oind].pl);
476 		if (m != NULL) {
477 			TAILQ_REMOVE(&fl[oind].pl, m, pageq);
478 			fl[oind].lcnt--;
479 			m->order = VM_NFREEORDER;
480 			vm_phys_split_pages(m, oind, fl, order);
481 			return (m);
482 		}
483 	}
484 
485 	/*
486 	 * The given pool was empty.  Find the largest
487 	 * contiguous, power-of-two-sized set of pages in any
488 	 * pool.  Transfer these pages to the given pool, and
489 	 * use them to satisfy the allocation.
490 	 */
491 	for (oind = VM_NFREEORDER - 1; oind >= order; oind--) {
492 		for (pind = 0; pind < VM_NFREEPOOL; pind++) {
493 			alt = (*vm_phys_lookup_lists[domain][flind])[pind];
494 			m = TAILQ_FIRST(&alt[oind].pl);
495 			if (m != NULL) {
496 				TAILQ_REMOVE(&alt[oind].pl, m, pageq);
497 				alt[oind].lcnt--;
498 				m->order = VM_NFREEORDER;
499 				vm_phys_set_pool(pool, m, oind);
500 				vm_phys_split_pages(m, oind, fl, order);
501 				return (m);
502 			}
503 		}
504 	}
505 	return (NULL);
506 }
507 
508 /*
509  * Find the vm_page corresponding to the given physical address.
510  */
511 vm_page_t
512 vm_phys_paddr_to_vm_page(vm_paddr_t pa)
513 {
514 	struct vm_phys_seg *seg;
515 	int segind;
516 
517 	for (segind = 0; segind < vm_phys_nsegs; segind++) {
518 		seg = &vm_phys_segs[segind];
519 		if (pa >= seg->start && pa < seg->end)
520 			return (&seg->first_page[atop(pa - seg->start)]);
521 	}
522 	return (NULL);
523 }
524 
525 vm_page_t
526 vm_phys_fictitious_to_vm_page(vm_paddr_t pa)
527 {
528 	struct vm_phys_fictitious_seg *seg;
529 	vm_page_t m;
530 	int segind;
531 
532 	m = NULL;
533 	for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
534 		seg = &vm_phys_fictitious_segs[segind];
535 		if (pa >= seg->start && pa < seg->end) {
536 			m = &seg->first_page[atop(pa - seg->start)];
537 			KASSERT((m->flags & PG_FICTITIOUS) != 0,
538 			    ("%p not fictitious", m));
539 			break;
540 		}
541 	}
542 	return (m);
543 }
544 
545 int
546 vm_phys_fictitious_reg_range(vm_paddr_t start, vm_paddr_t end,
547     vm_memattr_t memattr)
548 {
549 	struct vm_phys_fictitious_seg *seg;
550 	vm_page_t fp;
551 	long i, page_count;
552 	int segind;
553 #ifdef VM_PHYSSEG_DENSE
554 	long pi;
555 	boolean_t malloced;
556 #endif
557 
558 	page_count = (end - start) / PAGE_SIZE;
559 
560 #ifdef VM_PHYSSEG_DENSE
561 	pi = atop(start);
562 	if (pi >= first_page && atop(end) < vm_page_array_size) {
563 		fp = &vm_page_array[pi - first_page];
564 		malloced = FALSE;
565 	} else
566 #endif
567 	{
568 		fp = malloc(page_count * sizeof(struct vm_page), M_FICT_PAGES,
569 		    M_WAITOK | M_ZERO);
570 #ifdef VM_PHYSSEG_DENSE
571 		malloced = TRUE;
572 #endif
573 	}
574 	for (i = 0; i < page_count; i++) {
575 		vm_page_initfake(&fp[i], start + PAGE_SIZE * i, memattr);
576 		pmap_page_init(&fp[i]);
577 		fp[i].oflags &= ~(VPO_BUSY | VPO_UNMANAGED);
578 	}
579 	mtx_lock(&vm_phys_fictitious_reg_mtx);
580 	for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
581 		seg = &vm_phys_fictitious_segs[segind];
582 		if (seg->start == 0 && seg->end == 0) {
583 			seg->start = start;
584 			seg->end = end;
585 			seg->first_page = fp;
586 			mtx_unlock(&vm_phys_fictitious_reg_mtx);
587 			return (0);
588 		}
589 	}
590 	mtx_unlock(&vm_phys_fictitious_reg_mtx);
591 #ifdef VM_PHYSSEG_DENSE
592 	if (malloced)
593 #endif
594 		free(fp, M_FICT_PAGES);
595 	return (EBUSY);
596 }
597 
598 void
599 vm_phys_fictitious_unreg_range(vm_paddr_t start, vm_paddr_t end)
600 {
601 	struct vm_phys_fictitious_seg *seg;
602 	vm_page_t fp;
603 	int segind;
604 #ifdef VM_PHYSSEG_DENSE
605 	long pi;
606 #endif
607 
608 #ifdef VM_PHYSSEG_DENSE
609 	pi = atop(start);
610 #endif
611 
612 	mtx_lock(&vm_phys_fictitious_reg_mtx);
613 	for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
614 		seg = &vm_phys_fictitious_segs[segind];
615 		if (seg->start == start && seg->end == end) {
616 			seg->start = seg->end = 0;
617 			fp = seg->first_page;
618 			seg->first_page = NULL;
619 			mtx_unlock(&vm_phys_fictitious_reg_mtx);
620 #ifdef VM_PHYSSEG_DENSE
621 			if (pi < first_page || atop(end) >= vm_page_array_size)
622 #endif
623 				free(fp, M_FICT_PAGES);
624 			return;
625 		}
626 	}
627 	mtx_unlock(&vm_phys_fictitious_reg_mtx);
628 	KASSERT(0, ("Unregistering not registered fictitious range"));
629 }
630 
631 /*
632  * Find the segment containing the given physical address.
633  */
634 static int
635 vm_phys_paddr_to_segind(vm_paddr_t pa)
636 {
637 	struct vm_phys_seg *seg;
638 	int segind;
639 
640 	for (segind = 0; segind < vm_phys_nsegs; segind++) {
641 		seg = &vm_phys_segs[segind];
642 		if (pa >= seg->start && pa < seg->end)
643 			return (segind);
644 	}
645 	panic("vm_phys_paddr_to_segind: paddr %#jx is not in any segment" ,
646 	    (uintmax_t)pa);
647 }
648 
649 /*
650  * Free a contiguous, power of two-sized set of physical pages.
651  *
652  * The free page queues must be locked.
653  */
654 void
655 vm_phys_free_pages(vm_page_t m, int order)
656 {
657 	struct vm_freelist *fl;
658 	struct vm_phys_seg *seg;
659 	vm_paddr_t pa;
660 	vm_page_t m_buddy;
661 
662 	KASSERT(m->order == VM_NFREEORDER,
663 	    ("vm_phys_free_pages: page %p has unexpected order %d",
664 	    m, m->order));
665 	KASSERT(m->pool < VM_NFREEPOOL,
666 	    ("vm_phys_free_pages: page %p has unexpected pool %d",
667 	    m, m->pool));
668 	KASSERT(order < VM_NFREEORDER,
669 	    ("vm_phys_free_pages: order %d is out of range", order));
670 	mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
671 	seg = &vm_phys_segs[m->segind];
672 	if (order < VM_NFREEORDER - 1) {
673 		pa = VM_PAGE_TO_PHYS(m);
674 		do {
675 			pa ^= ((vm_paddr_t)1 << (PAGE_SHIFT + order));
676 			if (pa < seg->start || pa >= seg->end)
677 				break;
678 			m_buddy = &seg->first_page[atop(pa - seg->start)];
679 			if (m_buddy->order != order)
680 				break;
681 			fl = (*seg->free_queues)[m_buddy->pool];
682 			TAILQ_REMOVE(&fl[order].pl, m_buddy, pageq);
683 			fl[order].lcnt--;
684 			m_buddy->order = VM_NFREEORDER;
685 			if (m_buddy->pool != m->pool)
686 				vm_phys_set_pool(m->pool, m_buddy, order);
687 			order++;
688 			pa &= ~(((vm_paddr_t)1 << (PAGE_SHIFT + order)) - 1);
689 			m = &seg->first_page[atop(pa - seg->start)];
690 		} while (order < VM_NFREEORDER - 1);
691 	}
692 	m->order = order;
693 	fl = (*seg->free_queues)[m->pool];
694 	TAILQ_INSERT_TAIL(&fl[order].pl, m, pageq);
695 	fl[order].lcnt++;
696 }
697 
698 /*
699  * Free a contiguous, arbitrarily sized set of physical pages.
700  *
701  * The free page queues must be locked.
702  */
703 void
704 vm_phys_free_contig(vm_page_t m, u_long npages)
705 {
706 	u_int n;
707 	int order;
708 
709 	/*
710 	 * Avoid unnecessary coalescing by freeing the pages in the largest
711 	 * possible power-of-two-sized subsets.
712 	 */
713 	mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
714 	for (;; npages -= n) {
715 		/*
716 		 * Unsigned "min" is used here so that "order" is assigned
717 		 * "VM_NFREEORDER - 1" when "m"'s physical address is zero
718 		 * or the low-order bits of its physical address are zero
719 		 * because the size of a physical address exceeds the size of
720 		 * a long.
721 		 */
722 		order = min(ffsl(VM_PAGE_TO_PHYS(m) >> PAGE_SHIFT) - 1,
723 		    VM_NFREEORDER - 1);
724 		n = 1 << order;
725 		if (npages < n)
726 			break;
727 		vm_phys_free_pages(m, order);
728 		m += n;
729 	}
730 	/* The residual "npages" is less than "1 << (VM_NFREEORDER - 1)". */
731 	for (; npages > 0; npages -= n) {
732 		order = flsl(npages) - 1;
733 		n = 1 << order;
734 		vm_phys_free_pages(m, order);
735 		m += n;
736 	}
737 }
738 
739 /*
740  * Set the pool for a contiguous, power of two-sized set of physical pages.
741  */
742 void
743 vm_phys_set_pool(int pool, vm_page_t m, int order)
744 {
745 	vm_page_t m_tmp;
746 
747 	for (m_tmp = m; m_tmp < &m[1 << order]; m_tmp++)
748 		m_tmp->pool = pool;
749 }
750 
751 /*
752  * Search for the given physical page "m" in the free lists.  If the search
753  * succeeds, remove "m" from the free lists and return TRUE.  Otherwise, return
754  * FALSE, indicating that "m" is not in the free lists.
755  *
756  * The free page queues must be locked.
757  */
758 boolean_t
759 vm_phys_unfree_page(vm_page_t m)
760 {
761 	struct vm_freelist *fl;
762 	struct vm_phys_seg *seg;
763 	vm_paddr_t pa, pa_half;
764 	vm_page_t m_set, m_tmp;
765 	int order;
766 
767 	mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
768 
769 	/*
770 	 * First, find the contiguous, power of two-sized set of free
771 	 * physical pages containing the given physical page "m" and
772 	 * assign it to "m_set".
773 	 */
774 	seg = &vm_phys_segs[m->segind];
775 	for (m_set = m, order = 0; m_set->order == VM_NFREEORDER &&
776 	    order < VM_NFREEORDER - 1; ) {
777 		order++;
778 		pa = m->phys_addr & (~(vm_paddr_t)0 << (PAGE_SHIFT + order));
779 		if (pa >= seg->start)
780 			m_set = &seg->first_page[atop(pa - seg->start)];
781 		else
782 			return (FALSE);
783 	}
784 	if (m_set->order < order)
785 		return (FALSE);
786 	if (m_set->order == VM_NFREEORDER)
787 		return (FALSE);
788 	KASSERT(m_set->order < VM_NFREEORDER,
789 	    ("vm_phys_unfree_page: page %p has unexpected order %d",
790 	    m_set, m_set->order));
791 
792 	/*
793 	 * Next, remove "m_set" from the free lists.  Finally, extract
794 	 * "m" from "m_set" using an iterative algorithm: While "m_set"
795 	 * is larger than a page, shrink "m_set" by returning the half
796 	 * of "m_set" that does not contain "m" to the free lists.
797 	 */
798 	fl = (*seg->free_queues)[m_set->pool];
799 	order = m_set->order;
800 	TAILQ_REMOVE(&fl[order].pl, m_set, pageq);
801 	fl[order].lcnt--;
802 	m_set->order = VM_NFREEORDER;
803 	while (order > 0) {
804 		order--;
805 		pa_half = m_set->phys_addr ^ (1 << (PAGE_SHIFT + order));
806 		if (m->phys_addr < pa_half)
807 			m_tmp = &seg->first_page[atop(pa_half - seg->start)];
808 		else {
809 			m_tmp = m_set;
810 			m_set = &seg->first_page[atop(pa_half - seg->start)];
811 		}
812 		m_tmp->order = order;
813 		TAILQ_INSERT_HEAD(&fl[order].pl, m_tmp, pageq);
814 		fl[order].lcnt++;
815 	}
816 	KASSERT(m_set == m, ("vm_phys_unfree_page: fatal inconsistency"));
817 	return (TRUE);
818 }
819 
820 /*
821  * Try to zero one physical page.  Used by an idle priority thread.
822  */
823 boolean_t
824 vm_phys_zero_pages_idle(void)
825 {
826 	static struct vm_freelist *fl = vm_phys_free_queues[0][0];
827 	static int flind, oind, pind;
828 	vm_page_t m, m_tmp;
829 
830 	mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
831 	for (;;) {
832 		TAILQ_FOREACH_REVERSE(m, &fl[oind].pl, pglist, pageq) {
833 			for (m_tmp = m; m_tmp < &m[1 << oind]; m_tmp++) {
834 				if ((m_tmp->flags & (PG_CACHED | PG_ZERO)) == 0) {
835 					vm_phys_unfree_page(m_tmp);
836 					cnt.v_free_count--;
837 					mtx_unlock(&vm_page_queue_free_mtx);
838 					pmap_zero_page_idle(m_tmp);
839 					m_tmp->flags |= PG_ZERO;
840 					mtx_lock(&vm_page_queue_free_mtx);
841 					cnt.v_free_count++;
842 					vm_phys_free_pages(m_tmp, 0);
843 					vm_page_zero_count++;
844 					cnt_prezero++;
845 					return (TRUE);
846 				}
847 			}
848 		}
849 		oind++;
850 		if (oind == VM_NFREEORDER) {
851 			oind = 0;
852 			pind++;
853 			if (pind == VM_NFREEPOOL) {
854 				pind = 0;
855 				flind++;
856 				if (flind == vm_nfreelists)
857 					flind = 0;
858 			}
859 			fl = vm_phys_free_queues[flind][pind];
860 		}
861 	}
862 }
863 
864 /*
865  * Allocate a contiguous set of physical pages of the given size
866  * "npages" from the free lists.  All of the physical pages must be at
867  * or above the given physical address "low" and below the given
868  * physical address "high".  The given value "alignment" determines the
869  * alignment of the first physical page in the set.  If the given value
870  * "boundary" is non-zero, then the set of physical pages cannot cross
871  * any physical address boundary that is a multiple of that value.  Both
872  * "alignment" and "boundary" must be a power of two.
873  */
874 vm_page_t
875 vm_phys_alloc_contig(u_long npages, vm_paddr_t low, vm_paddr_t high,
876     u_long alignment, vm_paddr_t boundary)
877 {
878 	struct vm_freelist *fl;
879 	struct vm_phys_seg *seg;
880 	vm_paddr_t pa, pa_last, size;
881 	vm_page_t m, m_ret;
882 	u_long npages_end;
883 	int domain, flind, oind, order, pind;
884 
885 	mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
886 #if VM_NDOMAIN > 1
887 	domain = PCPU_GET(domain);
888 #else
889 	domain = 0;
890 #endif
891 	size = npages << PAGE_SHIFT;
892 	KASSERT(size != 0,
893 	    ("vm_phys_alloc_contig: size must not be 0"));
894 	KASSERT((alignment & (alignment - 1)) == 0,
895 	    ("vm_phys_alloc_contig: alignment must be a power of 2"));
896 	KASSERT((boundary & (boundary - 1)) == 0,
897 	    ("vm_phys_alloc_contig: boundary must be a power of 2"));
898 	/* Compute the queue that is the best fit for npages. */
899 	for (order = 0; (1 << order) < npages; order++);
900 	for (flind = 0; flind < vm_nfreelists; flind++) {
901 		for (oind = min(order, VM_NFREEORDER - 1); oind < VM_NFREEORDER; oind++) {
902 			for (pind = 0; pind < VM_NFREEPOOL; pind++) {
903 				fl = (*vm_phys_lookup_lists[domain][flind])
904 				    [pind];
905 				TAILQ_FOREACH(m_ret, &fl[oind].pl, pageq) {
906 					/*
907 					 * A free list may contain physical pages
908 					 * from one or more segments.
909 					 */
910 					seg = &vm_phys_segs[m_ret->segind];
911 					if (seg->start > high ||
912 					    low >= seg->end)
913 						continue;
914 
915 					/*
916 					 * Is the size of this allocation request
917 					 * larger than the largest block size?
918 					 */
919 					if (order >= VM_NFREEORDER) {
920 						/*
921 						 * Determine if a sufficient number
922 						 * of subsequent blocks to satisfy
923 						 * the allocation request are free.
924 						 */
925 						pa = VM_PAGE_TO_PHYS(m_ret);
926 						pa_last = pa + size;
927 						for (;;) {
928 							pa += 1 << (PAGE_SHIFT + VM_NFREEORDER - 1);
929 							if (pa >= pa_last)
930 								break;
931 							if (pa < seg->start ||
932 							    pa >= seg->end)
933 								break;
934 							m = &seg->first_page[atop(pa - seg->start)];
935 							if (m->order != VM_NFREEORDER - 1)
936 								break;
937 						}
938 						/* If not, continue to the next block. */
939 						if (pa < pa_last)
940 							continue;
941 					}
942 
943 					/*
944 					 * Determine if the blocks are within the given range,
945 					 * satisfy the given alignment, and do not cross the
946 					 * given boundary.
947 					 */
948 					pa = VM_PAGE_TO_PHYS(m_ret);
949 					if (pa >= low &&
950 					    pa + size <= high &&
951 					    (pa & (alignment - 1)) == 0 &&
952 					    ((pa ^ (pa + size - 1)) & ~(boundary - 1)) == 0)
953 						goto done;
954 				}
955 			}
956 		}
957 	}
958 	return (NULL);
959 done:
960 	for (m = m_ret; m < &m_ret[npages]; m = &m[1 << oind]) {
961 		fl = (*seg->free_queues)[m->pool];
962 		TAILQ_REMOVE(&fl[m->order].pl, m, pageq);
963 		fl[m->order].lcnt--;
964 		m->order = VM_NFREEORDER;
965 	}
966 	if (m_ret->pool != VM_FREEPOOL_DEFAULT)
967 		vm_phys_set_pool(VM_FREEPOOL_DEFAULT, m_ret, oind);
968 	fl = (*seg->free_queues)[m_ret->pool];
969 	vm_phys_split_pages(m_ret, oind, fl, order);
970 	/* Return excess pages to the free lists. */
971 	npages_end = roundup2(npages, 1 << imin(oind, order));
972 	if (npages < npages_end)
973 		vm_phys_free_contig(&m_ret[npages], npages_end - npages);
974 	return (m_ret);
975 }
976 
977 #ifdef DDB
978 /*
979  * Show the number of physical pages in each of the free lists.
980  */
981 DB_SHOW_COMMAND(freepages, db_show_freepages)
982 {
983 	struct vm_freelist *fl;
984 	int flind, oind, pind;
985 
986 	for (flind = 0; flind < vm_nfreelists; flind++) {
987 		db_printf("FREE LIST %d:\n"
988 		    "\n  ORDER (SIZE)  |  NUMBER"
989 		    "\n              ", flind);
990 		for (pind = 0; pind < VM_NFREEPOOL; pind++)
991 			db_printf("  |  POOL %d", pind);
992 		db_printf("\n--            ");
993 		for (pind = 0; pind < VM_NFREEPOOL; pind++)
994 			db_printf("-- --      ");
995 		db_printf("--\n");
996 		for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
997 			db_printf("  %2.2d (%6.6dK)", oind,
998 			    1 << (PAGE_SHIFT - 10 + oind));
999 			for (pind = 0; pind < VM_NFREEPOOL; pind++) {
1000 				fl = vm_phys_free_queues[flind][pind];
1001 				db_printf("  |  %6.6d", fl[oind].lcnt);
1002 			}
1003 			db_printf("\n");
1004 		}
1005 		db_printf("\n");
1006 	}
1007 }
1008 #endif
1009