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