pmap.c revision 74283
1/*
2 * Copyright (c) 1991 Regents of the University of California.
3 * All rights reserved.
4 * Copyright (c) 1994 John S. Dyson
5 * All rights reserved.
6 * Copyright (c) 1994 David Greenman
7 * All rights reserved.
8 *
9 * This code is derived from software contributed to Berkeley by
10 * the Systems Programming Group of the University of Utah Computer
11 * Science Department and William Jolitz of UUNET Technologies Inc.
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 the University of
24 *	California, Berkeley and its contributors.
25 * 4. Neither the name of the University nor the names of its contributors
26 *    may be used to endorse or promote products derived from this software
27 *    without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 * SUCH DAMAGE.
40 *
41 *	from:	@(#)pmap.c	7.7 (Berkeley)	5/12/91
42 * $FreeBSD: head/sys/i386/i386/pmap.c 74283 2001-03-15 05:10:06Z peter $
43 */
44
45/*
46 *	Manages physical address maps.
47 *
48 *	In addition to hardware address maps, this
49 *	module is called upon to provide software-use-only
50 *	maps which may or may not be stored in the same
51 *	form as hardware maps.  These pseudo-maps are
52 *	used to store intermediate results from copy
53 *	operations to and from address spaces.
54 *
55 *	Since the information managed by this module is
56 *	also stored by the logical address mapping module,
57 *	this module may throw away valid virtual-to-physical
58 *	mappings at almost any time.  However, invalidations
59 *	of virtual-to-physical mappings must be done as
60 *	requested.
61 *
62 *	In order to cope with hardware architectures which
63 *	make virtual-to-physical map invalidates expensive,
64 *	this module may delay invalidate or reduced protection
65 *	operations until such time as they are actually
66 *	necessary.  This module is given full information as
67 *	to which processors are currently using which maps,
68 *	and to when physical maps must be made correct.
69 */
70
71#include "opt_disable_pse.h"
72#include "opt_pmap.h"
73#include "opt_msgbuf.h"
74
75#include <sys/param.h>
76#include <sys/systm.h>
77#include <sys/proc.h>
78#include <sys/msgbuf.h>
79#include <sys/vmmeter.h>
80#include <sys/mman.h>
81
82#include <vm/vm.h>
83#include <vm/vm_param.h>
84#include <sys/lock.h>
85#include <vm/vm_kern.h>
86#include <vm/vm_page.h>
87#include <vm/vm_map.h>
88#include <vm/vm_object.h>
89#include <vm/vm_extern.h>
90#include <vm/vm_pageout.h>
91#include <vm/vm_pager.h>
92#include <vm/vm_zone.h>
93
94#include <sys/user.h>
95
96#include <machine/cputypes.h>
97#include <machine/md_var.h>
98#include <machine/specialreg.h>
99#if defined(SMP) || defined(APIC_IO)
100#include <machine/smp.h>
101#include <machine/apic.h>
102#include <machine/segments.h>
103#include <machine/tss.h>
104#include <machine/globaldata.h>
105#endif /* SMP || APIC_IO */
106
107#define PMAP_KEEP_PDIRS
108#ifndef PMAP_SHPGPERPROC
109#define PMAP_SHPGPERPROC 200
110#endif
111
112#if defined(DIAGNOSTIC)
113#define PMAP_DIAGNOSTIC
114#endif
115
116#define MINPV 2048
117
118#if !defined(PMAP_DIAGNOSTIC)
119#define PMAP_INLINE __inline
120#else
121#define PMAP_INLINE
122#endif
123
124/*
125 * Get PDEs and PTEs for user/kernel address space
126 */
127#define	pmap_pde(m, v)	(&((m)->pm_pdir[(vm_offset_t)(v) >> PDRSHIFT]))
128#define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT])
129
130#define pmap_pde_v(pte)		((*(int *)pte & PG_V) != 0)
131#define pmap_pte_w(pte)		((*(int *)pte & PG_W) != 0)
132#define pmap_pte_m(pte)		((*(int *)pte & PG_M) != 0)
133#define pmap_pte_u(pte)		((*(int *)pte & PG_A) != 0)
134#define pmap_pte_v(pte)		((*(int *)pte & PG_V) != 0)
135
136#define pmap_pte_set_w(pte, v) ((v)?(*(int *)pte |= PG_W):(*(int *)pte &= ~PG_W))
137#define pmap_pte_set_prot(pte, v) ((*(int *)pte &= ~PG_PROT), (*(int *)pte |= (v)))
138
139/*
140 * Given a map and a machine independent protection code,
141 * convert to a vax protection code.
142 */
143#define pte_prot(m, p)	(protection_codes[p])
144static int protection_codes[8];
145
146static struct pmap kernel_pmap_store;
147pmap_t kernel_pmap;
148LIST_HEAD(pmaplist, pmap);
149struct pmaplist allpmaps;
150
151vm_offset_t avail_start;	/* PA of first available physical page */
152vm_offset_t avail_end;		/* PA of last available physical page */
153vm_offset_t virtual_avail;	/* VA of first avail page (after kernel bss) */
154vm_offset_t virtual_end;	/* VA of last avail page (end of kernel AS) */
155static boolean_t pmap_initialized = FALSE;	/* Has pmap_init completed? */
156static int pgeflag;		/* PG_G or-in */
157static int pseflag;		/* PG_PS or-in */
158
159static vm_object_t kptobj;
160
161static int nkpt;
162vm_offset_t kernel_vm_end;
163
164/*
165 * Data for the pv entry allocation mechanism
166 */
167static vm_zone_t pvzone;
168static struct vm_zone pvzone_store;
169static struct vm_object pvzone_obj;
170static int pv_entry_count=0, pv_entry_max=0, pv_entry_high_water=0;
171static int pmap_pagedaemon_waken = 0;
172static struct pv_entry *pvinit;
173
174/*
175 * All those kernel PT submaps that BSD is so fond of
176 */
177pt_entry_t *CMAP1 = 0;
178static pt_entry_t *CMAP2, *ptmmap;
179caddr_t CADDR1 = 0, ptvmmap = 0;
180static caddr_t CADDR2;
181static pt_entry_t *msgbufmap;
182struct msgbuf *msgbufp=0;
183
184/*
185 * Crashdump maps.
186 */
187static pt_entry_t *pt_crashdumpmap;
188static caddr_t crashdumpmap;
189
190#ifdef SMP
191extern pt_entry_t *SMPpt;
192#endif
193static pt_entry_t *PMAP1 = 0;
194static unsigned *PADDR1 = 0;
195
196static PMAP_INLINE void	free_pv_entry __P((pv_entry_t pv));
197static unsigned * get_ptbase __P((pmap_t pmap));
198static pv_entry_t get_pv_entry __P((void));
199static void	i386_protection_init __P((void));
200static __inline void	pmap_changebit __P((vm_page_t m, int bit, boolean_t setem));
201
202static void	pmap_remove_all __P((vm_page_t m));
203static vm_page_t pmap_enter_quick __P((pmap_t pmap, vm_offset_t va,
204				      vm_page_t m, vm_page_t mpte));
205static int pmap_remove_pte __P((struct pmap *pmap, unsigned *ptq,
206					vm_offset_t sva));
207static void pmap_remove_page __P((struct pmap *pmap, vm_offset_t va));
208static int pmap_remove_entry __P((struct pmap *pmap, vm_page_t m,
209					vm_offset_t va));
210static boolean_t pmap_testbit __P((vm_page_t m, int bit));
211static void pmap_insert_entry __P((pmap_t pmap, vm_offset_t va,
212		vm_page_t mpte, vm_page_t m));
213
214static vm_page_t pmap_allocpte __P((pmap_t pmap, vm_offset_t va));
215
216static int pmap_release_free_page __P((pmap_t pmap, vm_page_t p));
217static vm_page_t _pmap_allocpte __P((pmap_t pmap, unsigned ptepindex));
218static unsigned * pmap_pte_quick __P((pmap_t pmap, vm_offset_t va));
219static vm_page_t pmap_page_lookup __P((vm_object_t object, vm_pindex_t pindex));
220static int pmap_unuse_pt __P((pmap_t, vm_offset_t, vm_page_t));
221static vm_offset_t pmap_kmem_choose(vm_offset_t addr);
222
223static unsigned pdir4mb;
224
225/*
226 *	Routine:	pmap_pte
227 *	Function:
228 *		Extract the page table entry associated
229 *		with the given map/virtual_address pair.
230 */
231
232PMAP_INLINE unsigned *
233pmap_pte(pmap, va)
234	register pmap_t pmap;
235	vm_offset_t va;
236{
237	unsigned *pdeaddr;
238
239	if (pmap) {
240		pdeaddr = (unsigned *) pmap_pde(pmap, va);
241		if (*pdeaddr & PG_PS)
242			return pdeaddr;
243		if (*pdeaddr) {
244			return get_ptbase(pmap) + i386_btop(va);
245		}
246	}
247	return (0);
248}
249
250/*
251 * Move the kernel virtual free pointer to the next
252 * 4MB.  This is used to help improve performance
253 * by using a large (4MB) page for much of the kernel
254 * (.text, .data, .bss)
255 */
256static vm_offset_t
257pmap_kmem_choose(vm_offset_t addr)
258{
259	vm_offset_t newaddr = addr;
260#ifndef DISABLE_PSE
261	if (cpu_feature & CPUID_PSE) {
262		newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1);
263	}
264#endif
265	return newaddr;
266}
267
268/*
269 *	Bootstrap the system enough to run with virtual memory.
270 *
271 *	On the i386 this is called after mapping has already been enabled
272 *	and just syncs the pmap module with what has already been done.
273 *	[We can't call it easily with mapping off since the kernel is not
274 *	mapped with PA == VA, hence we would have to relocate every address
275 *	from the linked base (virtual) address "KERNBASE" to the actual
276 *	(physical) address starting relative to 0]
277 */
278void
279pmap_bootstrap(firstaddr, loadaddr)
280	vm_offset_t firstaddr;
281	vm_offset_t loadaddr;
282{
283	vm_offset_t va;
284	pt_entry_t *pte;
285	int i;
286
287	avail_start = firstaddr;
288
289	/*
290	 * XXX The calculation of virtual_avail is wrong. It's NKPT*PAGE_SIZE too
291	 * large. It should instead be correctly calculated in locore.s and
292	 * not based on 'first' (which is a physical address, not a virtual
293	 * address, for the start of unused physical memory). The kernel
294	 * page tables are NOT double mapped and thus should not be included
295	 * in this calculation.
296	 */
297	virtual_avail = (vm_offset_t) KERNBASE + firstaddr;
298	virtual_avail = pmap_kmem_choose(virtual_avail);
299
300	virtual_end = VM_MAX_KERNEL_ADDRESS;
301
302	/*
303	 * Initialize protection array.
304	 */
305	i386_protection_init();
306
307	/*
308	 * The kernel's pmap is statically allocated so we don't have to use
309	 * pmap_create, which is unlikely to work correctly at this part of
310	 * the boot sequence (XXX and which no longer exists).
311	 */
312	kernel_pmap = &kernel_pmap_store;
313
314	kernel_pmap->pm_pdir = (pd_entry_t *) (KERNBASE + (u_int)IdlePTD);
315	kernel_pmap->pm_count = 1;
316	kernel_pmap->pm_active = -1;	/* don't allow deactivation */
317	TAILQ_INIT(&kernel_pmap->pm_pvlist);
318	LIST_INIT(&allpmaps);
319	LIST_INSERT_HEAD(&allpmaps, kernel_pmap, pm_list);
320	nkpt = NKPT;
321
322	/*
323	 * Reserve some special page table entries/VA space for temporary
324	 * mapping of pages.
325	 */
326#define	SYSMAP(c, p, v, n)	\
327	v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n);
328
329	va = virtual_avail;
330	pte = (pt_entry_t *) pmap_pte(kernel_pmap, va);
331
332	/*
333	 * CMAP1/CMAP2 are used for zeroing and copying pages.
334	 */
335	SYSMAP(caddr_t, CMAP1, CADDR1, 1)
336	SYSMAP(caddr_t, CMAP2, CADDR2, 1)
337
338	/*
339	 * Crashdump maps.
340	 */
341	SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS);
342
343	/*
344	 * ptvmmap is used for reading arbitrary physical pages via /dev/mem.
345	 * XXX ptmmap is not used.
346	 */
347	SYSMAP(caddr_t, ptmmap, ptvmmap, 1)
348
349	/*
350	 * msgbufp is used to map the system message buffer.
351	 * XXX msgbufmap is not used.
352	 */
353	SYSMAP(struct msgbuf *, msgbufmap, msgbufp,
354	       atop(round_page(MSGBUF_SIZE)))
355
356	/*
357	 * ptemap is used for pmap_pte_quick
358	 */
359	SYSMAP(unsigned *, PMAP1, PADDR1, 1);
360
361	virtual_avail = va;
362
363	*(int *) CMAP1 = *(int *) CMAP2 = 0;
364	for (i = 0; i < NKPT; i++)
365		PTD[i] = 0;
366
367	pgeflag = 0;
368#if !defined(SMP)			/* XXX - see also mp_machdep.c */
369	if (cpu_feature & CPUID_PGE) {
370		pgeflag = PG_G;
371	}
372#endif
373
374/*
375 * Initialize the 4MB page size flag
376 */
377	pseflag = 0;
378/*
379 * The 4MB page version of the initial
380 * kernel page mapping.
381 */
382	pdir4mb = 0;
383
384#if !defined(DISABLE_PSE)
385	if (cpu_feature & CPUID_PSE) {
386		unsigned ptditmp;
387		/*
388		 * Note that we have enabled PSE mode
389		 */
390		pseflag = PG_PS;
391		ptditmp = *((unsigned *)PTmap + i386_btop(KERNBASE));
392		ptditmp &= ~(NBPDR - 1);
393		ptditmp |= PG_V | PG_RW | PG_PS | PG_U | pgeflag;
394		pdir4mb = ptditmp;
395
396#if !defined(SMP)
397		/*
398		 * Enable the PSE mode.
399		 */
400		load_cr4(rcr4() | CR4_PSE);
401
402		/*
403		 * We can do the mapping here for the single processor
404		 * case.  We simply ignore the old page table page from
405		 * now on.
406		 */
407		/*
408		 * For SMP, we still need 4K pages to bootstrap APs,
409		 * PSE will be enabled as soon as all APs are up.
410		 */
411		PTD[KPTDI] = (pd_entry_t) ptditmp;
412		kernel_pmap->pm_pdir[KPTDI] = (pd_entry_t) ptditmp;
413		invltlb();
414#endif
415	}
416#endif
417
418#ifdef SMP
419	if (cpu_apic_address == 0)
420		panic("pmap_bootstrap: no local apic! (non-SMP hardware?)");
421
422	/* local apic is mapped on last page */
423	SMPpt[NPTEPG - 1] = (pt_entry_t)(PG_V | PG_RW | PG_N | pgeflag |
424	    (cpu_apic_address & PG_FRAME));
425#endif
426
427	invltlb();
428}
429
430#ifdef SMP
431/*
432 * Set 4mb pdir for mp startup
433 */
434void
435pmap_set_opt(void)
436{
437	if (pseflag && (cpu_feature & CPUID_PSE)) {
438		load_cr4(rcr4() | CR4_PSE);
439		if (pdir4mb && PCPU_GET(cpuid) == 0) {	/* only on BSP */
440			kernel_pmap->pm_pdir[KPTDI] =
441			    PTD[KPTDI] = (pd_entry_t)pdir4mb;
442			cpu_invltlb();
443		}
444	}
445}
446#endif
447
448/*
449 *	Initialize the pmap module.
450 *	Called by vm_init, to initialize any structures that the pmap
451 *	system needs to map virtual memory.
452 *	pmap_init has been enhanced to support in a fairly consistant
453 *	way, discontiguous physical memory.
454 */
455void
456pmap_init(phys_start, phys_end)
457	vm_offset_t phys_start, phys_end;
458{
459	int i;
460	int initial_pvs;
461
462	/*
463	 * object for kernel page table pages
464	 */
465	kptobj = vm_object_allocate(OBJT_DEFAULT, NKPDE);
466
467	/*
468	 * Allocate memory for random pmap data structures.  Includes the
469	 * pv_head_table.
470	 */
471
472	for(i = 0; i < vm_page_array_size; i++) {
473		vm_page_t m;
474
475		m = &vm_page_array[i];
476		TAILQ_INIT(&m->md.pv_list);
477		m->md.pv_list_count = 0;
478	}
479
480	/*
481	 * init the pv free list
482	 */
483	initial_pvs = vm_page_array_size;
484	if (initial_pvs < MINPV)
485		initial_pvs = MINPV;
486	pvzone = &pvzone_store;
487	pvinit = (struct pv_entry *) kmem_alloc(kernel_map,
488		initial_pvs * sizeof (struct pv_entry));
489	zbootinit(pvzone, "PV ENTRY", sizeof (struct pv_entry), pvinit,
490	    vm_page_array_size);
491
492	/*
493	 * Now it is safe to enable pv_table recording.
494	 */
495	pmap_initialized = TRUE;
496}
497
498/*
499 * Initialize the address space (zone) for the pv_entries.  Set a
500 * high water mark so that the system can recover from excessive
501 * numbers of pv entries.
502 */
503void
504pmap_init2()
505{
506	pv_entry_max = PMAP_SHPGPERPROC * maxproc + vm_page_array_size;
507	pv_entry_high_water = 9 * (pv_entry_max / 10);
508	zinitna(pvzone, &pvzone_obj, NULL, 0, pv_entry_max, ZONE_INTERRUPT, 1);
509}
510
511
512/***************************************************
513 * Low level helper routines.....
514 ***************************************************/
515
516#if defined(PMAP_DIAGNOSTIC)
517
518/*
519 * This code checks for non-writeable/modified pages.
520 * This should be an invalid condition.
521 */
522static int
523pmap_nw_modified(pt_entry_t ptea)
524{
525	int pte;
526
527	pte = (int) ptea;
528
529	if ((pte & (PG_M|PG_RW)) == PG_M)
530		return 1;
531	else
532		return 0;
533}
534#endif
535
536
537/*
538 * this routine defines the region(s) of memory that should
539 * not be tested for the modified bit.
540 */
541static PMAP_INLINE int
542pmap_track_modified(vm_offset_t va)
543{
544	if ((va < clean_sva) || (va >= clean_eva))
545		return 1;
546	else
547		return 0;
548}
549
550static PMAP_INLINE void
551invltlb_1pg(vm_offset_t va)
552{
553#ifdef I386_CPU
554	invltlb();
555#else
556	invlpg(va);
557#endif
558}
559
560static __inline void
561pmap_TLB_invalidate(pmap_t pmap, vm_offset_t va)
562{
563#if defined(SMP)
564	if (pmap->pm_active & (1 << PCPU_GET(cpuid)))
565		cpu_invlpg((void *)va);
566	if (pmap->pm_active & PCPU_GET(other_cpus))
567		smp_invltlb();
568#else
569	if (pmap->pm_active)
570		invltlb_1pg(va);
571#endif
572}
573
574static __inline void
575pmap_TLB_invalidate_all(pmap_t pmap)
576{
577#if defined(SMP)
578	if (pmap->pm_active & (1 << PCPU_GET(cpuid)))
579		cpu_invltlb();
580	if (pmap->pm_active & PCPU_GET(other_cpus))
581		smp_invltlb();
582#else
583	if (pmap->pm_active)
584		invltlb();
585#endif
586}
587
588static unsigned *
589get_ptbase(pmap)
590	pmap_t pmap;
591{
592	unsigned frame = (unsigned) pmap->pm_pdir[PTDPTDI] & PG_FRAME;
593
594	/* are we current address space or kernel? */
595	if (pmap == kernel_pmap || frame == (((unsigned) PTDpde) & PG_FRAME)) {
596		return (unsigned *) PTmap;
597	}
598	/* otherwise, we are alternate address space */
599	if (frame != (((unsigned) APTDpde) & PG_FRAME)) {
600		APTDpde = (pd_entry_t) (frame | PG_RW | PG_V);
601#if defined(SMP)
602		/* The page directory is not shared between CPUs */
603		cpu_invltlb();
604#else
605		invltlb();
606#endif
607	}
608	return (unsigned *) APTmap;
609}
610
611/*
612 * Super fast pmap_pte routine best used when scanning
613 * the pv lists.  This eliminates many coarse-grained
614 * invltlb calls.  Note that many of the pv list
615 * scans are across different pmaps.  It is very wasteful
616 * to do an entire invltlb for checking a single mapping.
617 */
618
619static unsigned *
620pmap_pte_quick(pmap, va)
621	register pmap_t pmap;
622	vm_offset_t va;
623{
624	unsigned pde, newpf;
625	if ((pde = (unsigned) pmap->pm_pdir[va >> PDRSHIFT]) != 0) {
626		unsigned frame = (unsigned) pmap->pm_pdir[PTDPTDI] & PG_FRAME;
627		unsigned index = i386_btop(va);
628		/* are we current address space or kernel? */
629		if ((pmap == kernel_pmap) ||
630			(frame == (((unsigned) PTDpde) & PG_FRAME))) {
631			return (unsigned *) PTmap + index;
632		}
633		newpf = pde & PG_FRAME;
634		if ( ((* (unsigned *) PMAP1) & PG_FRAME) != newpf) {
635			* (unsigned *) PMAP1 = newpf | PG_RW | PG_V;
636			invltlb_1pg((vm_offset_t) PADDR1);
637		}
638		return PADDR1 + ((unsigned) index & (NPTEPG - 1));
639	}
640	return (0);
641}
642
643/*
644 *	Routine:	pmap_extract
645 *	Function:
646 *		Extract the physical page address associated
647 *		with the given map/virtual_address pair.
648 */
649vm_offset_t
650pmap_extract(pmap, va)
651	register pmap_t pmap;
652	vm_offset_t va;
653{
654	vm_offset_t rtval;
655	vm_offset_t pdirindex;
656	pdirindex = va >> PDRSHIFT;
657	if (pmap && (rtval = (unsigned) pmap->pm_pdir[pdirindex])) {
658		unsigned *pte;
659		if ((rtval & PG_PS) != 0) {
660			rtval &= ~(NBPDR - 1);
661			rtval |= va & (NBPDR - 1);
662			return rtval;
663		}
664		pte = get_ptbase(pmap) + i386_btop(va);
665		rtval = ((*pte & PG_FRAME) | (va & PAGE_MASK));
666		return rtval;
667	}
668	return 0;
669
670}
671
672/***************************************************
673 * Low level mapping routines.....
674 ***************************************************/
675
676/*
677 * add a wired page to the kva
678 * note that in order for the mapping to take effect -- you
679 * should do a invltlb after doing the pmap_kenter...
680 */
681PMAP_INLINE void
682pmap_kenter(va, pa)
683	vm_offset_t va;
684	register vm_offset_t pa;
685{
686	register unsigned *pte;
687	unsigned npte, opte;
688
689	npte = pa | PG_RW | PG_V | pgeflag;
690	pte = (unsigned *)vtopte(va);
691	opte = *pte;
692	*pte = npte;
693	/*if (opte)*/
694		invltlb_1pg(va);	/* XXX what about SMP? */
695}
696
697/*
698 * remove a page from the kernel pagetables
699 */
700PMAP_INLINE void
701pmap_kremove(va)
702	vm_offset_t va;
703{
704	register unsigned *pte;
705
706	pte = (unsigned *)vtopte(va);
707	*pte = 0;
708	invltlb_1pg(va);	/* XXX what about SMP? */
709}
710
711/*
712 *	Used to map a range of physical addresses into kernel
713 *	virtual address space.
714 *
715 *	The value passed in '*virt' is a suggested virtual address for
716 *	the mapping. Architectures which can support a direct-mapped
717 *	physical to virtual region can return the appropriate address
718 *	within that region, leaving '*virt' unchanged. Other
719 *	architectures should map the pages starting at '*virt' and
720 *	update '*virt' with the first usable address after the mapped
721 *	region.
722 */
723vm_offset_t
724pmap_map(virt, start, end, prot)
725	vm_offset_t *virt;
726	vm_offset_t start;
727	vm_offset_t end;
728	int prot;
729{
730	vm_offset_t sva = *virt;
731	vm_offset_t va = sva;
732	while (start < end) {
733		pmap_kenter(va, start);
734		va += PAGE_SIZE;
735		start += PAGE_SIZE;
736	}
737	*virt = va;
738	return (sva);
739}
740
741
742/*
743 * Add a list of wired pages to the kva
744 * this routine is only used for temporary
745 * kernel mappings that do not need to have
746 * page modification or references recorded.
747 * Note that old mappings are simply written
748 * over.  The page *must* be wired.
749 */
750void
751pmap_qenter(va, m, count)
752	vm_offset_t va;
753	vm_page_t *m;
754	int count;
755{
756	int i;
757
758	for (i = 0; i < count; i++) {
759		vm_offset_t tva = va + i * PAGE_SIZE;
760		pmap_kenter(tva, VM_PAGE_TO_PHYS(m[i]));
761	}
762}
763
764/*
765 * this routine jerks page mappings from the
766 * kernel -- it is meant only for temporary mappings.
767 */
768void
769pmap_qremove(va, count)
770	vm_offset_t va;
771	int count;
772{
773	vm_offset_t end_va;
774
775	end_va = va + count*PAGE_SIZE;
776
777	while (va < end_va) {
778		unsigned *pte;
779
780		pte = (unsigned *)vtopte(va);
781		*pte = 0;
782#ifdef SMP
783		cpu_invlpg((void *)va);
784#else
785		invltlb_1pg(va);
786#endif
787		va += PAGE_SIZE;
788	}
789#ifdef SMP
790	smp_invltlb();
791#endif
792}
793
794static vm_page_t
795pmap_page_lookup(object, pindex)
796	vm_object_t object;
797	vm_pindex_t pindex;
798{
799	vm_page_t m;
800retry:
801	m = vm_page_lookup(object, pindex);
802	if (m && vm_page_sleep_busy(m, FALSE, "pplookp"))
803		goto retry;
804	return m;
805}
806
807/*
808 * Create the UPAGES for a new process.
809 * This routine directly affects the fork perf for a process.
810 */
811void
812pmap_new_proc(p)
813	struct proc *p;
814{
815#ifdef I386_CPU
816	int updateneeded;
817#endif
818	int i;
819	vm_object_t upobj;
820	vm_page_t m;
821	struct user *up;
822	unsigned *ptek, oldpte;
823
824	/*
825	 * allocate object for the upages
826	 */
827	if ((upobj = p->p_upages_obj) == NULL) {
828		upobj = vm_object_allocate( OBJT_DEFAULT, UPAGES);
829		p->p_upages_obj = upobj;
830	}
831
832	/* get a kernel virtual address for the UPAGES for this proc */
833	if ((up = p->p_addr) == NULL) {
834		up = (struct user *) kmem_alloc_nofault(kernel_map,
835				UPAGES * PAGE_SIZE);
836		if (up == NULL)
837			panic("pmap_new_proc: u_map allocation failed");
838		p->p_addr = up;
839	}
840
841	ptek = (unsigned *) vtopte((vm_offset_t) up);
842
843#ifdef I386_CPU
844	updateneeded = 0;
845#endif
846	for(i=0;i<UPAGES;i++) {
847		/*
848		 * Get a kernel stack page
849		 */
850		m = vm_page_grab(upobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY);
851
852		/*
853		 * Wire the page
854		 */
855		m->wire_count++;
856		cnt.v_wire_count++;
857
858		oldpte = *(ptek + i);
859		/*
860		 * Enter the page into the kernel address space.
861		 */
862		*(ptek + i) = VM_PAGE_TO_PHYS(m) | PG_RW | PG_V | pgeflag;
863		if (oldpte) {
864#ifdef I386_CPU
865			updateneeded = 1;
866#else
867			invlpg((vm_offset_t) up + i * PAGE_SIZE);
868#endif
869		}
870
871		vm_page_wakeup(m);
872		vm_page_flag_clear(m, PG_ZERO);
873		vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE);
874		m->valid = VM_PAGE_BITS_ALL;
875	}
876#ifdef I386_CPU
877	if (updateneeded)
878		invltlb();
879#endif
880}
881
882/*
883 * Dispose the UPAGES for a process that has exited.
884 * This routine directly impacts the exit perf of a process.
885 */
886void
887pmap_dispose_proc(p)
888	struct proc *p;
889{
890	int i;
891	vm_object_t upobj;
892	vm_page_t m;
893	unsigned *ptek, oldpte;
894
895	upobj = p->p_upages_obj;
896
897	ptek = (unsigned *) vtopte((vm_offset_t) p->p_addr);
898	for(i=0;i<UPAGES;i++) {
899
900		if ((m = vm_page_lookup(upobj, i)) == NULL)
901			panic("pmap_dispose_proc: upage already missing???");
902
903		vm_page_busy(m);
904
905		oldpte = *(ptek + i);
906		*(ptek + i) = 0;
907#ifndef I386_CPU
908		invlpg((vm_offset_t) p->p_addr + i * PAGE_SIZE);
909#endif
910		vm_page_unwire(m, 0);
911		vm_page_free(m);
912	}
913#ifdef I386_CPU
914	invltlb();
915#endif
916}
917
918/*
919 * Allow the UPAGES for a process to be prejudicially paged out.
920 */
921void
922pmap_swapout_proc(p)
923	struct proc *p;
924{
925	int i;
926	vm_object_t upobj;
927	vm_page_t m;
928
929	upobj = p->p_upages_obj;
930	/*
931	 * let the upages be paged
932	 */
933	for(i=0;i<UPAGES;i++) {
934		if ((m = vm_page_lookup(upobj, i)) == NULL)
935			panic("pmap_swapout_proc: upage already missing???");
936		vm_page_dirty(m);
937		vm_page_unwire(m, 0);
938		pmap_kremove( (vm_offset_t) p->p_addr + PAGE_SIZE * i);
939	}
940}
941
942/*
943 * Bring the UPAGES for a specified process back in.
944 */
945void
946pmap_swapin_proc(p)
947	struct proc *p;
948{
949	int i,rv;
950	vm_object_t upobj;
951	vm_page_t m;
952
953	upobj = p->p_upages_obj;
954	for(i=0;i<UPAGES;i++) {
955
956		m = vm_page_grab(upobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY);
957
958		pmap_kenter(((vm_offset_t) p->p_addr) + i * PAGE_SIZE,
959			VM_PAGE_TO_PHYS(m));
960
961		if (m->valid != VM_PAGE_BITS_ALL) {
962			rv = vm_pager_get_pages(upobj, &m, 1, 0);
963			if (rv != VM_PAGER_OK)
964				panic("pmap_swapin_proc: cannot get upages for proc: %d\n", p->p_pid);
965			m = vm_page_lookup(upobj, i);
966			m->valid = VM_PAGE_BITS_ALL;
967		}
968
969		vm_page_wire(m);
970		vm_page_wakeup(m);
971		vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE);
972	}
973}
974
975/***************************************************
976 * Page table page management routines.....
977 ***************************************************/
978
979/*
980 * This routine unholds page table pages, and if the hold count
981 * drops to zero, then it decrements the wire count.
982 */
983static int
984_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) {
985
986	while (vm_page_sleep_busy(m, FALSE, "pmuwpt"))
987		;
988
989	if (m->hold_count == 0) {
990		vm_offset_t pteva;
991		/*
992		 * unmap the page table page
993		 */
994		pmap->pm_pdir[m->pindex] = 0;
995		--pmap->pm_stats.resident_count;
996		if ((((unsigned)pmap->pm_pdir[PTDPTDI]) & PG_FRAME) ==
997			(((unsigned) PTDpde) & PG_FRAME)) {
998			/*
999			 * Do a invltlb to make the invalidated mapping
1000			 * take effect immediately.
1001			 */
1002			pteva = UPT_MIN_ADDRESS + i386_ptob(m->pindex);
1003			pmap_TLB_invalidate(pmap, pteva);
1004		}
1005
1006		if (pmap->pm_ptphint == m)
1007			pmap->pm_ptphint = NULL;
1008
1009		/*
1010		 * If the page is finally unwired, simply free it.
1011		 */
1012		--m->wire_count;
1013		if (m->wire_count == 0) {
1014
1015			vm_page_flash(m);
1016			vm_page_busy(m);
1017			vm_page_free_zero(m);
1018			--cnt.v_wire_count;
1019		}
1020		return 1;
1021	}
1022	return 0;
1023}
1024
1025static PMAP_INLINE int
1026pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m)
1027{
1028	vm_page_unhold(m);
1029	if (m->hold_count == 0)
1030		return _pmap_unwire_pte_hold(pmap, m);
1031	else
1032		return 0;
1033}
1034
1035/*
1036 * After removing a page table entry, this routine is used to
1037 * conditionally free the page, and manage the hold/wire counts.
1038 */
1039static int
1040pmap_unuse_pt(pmap, va, mpte)
1041	pmap_t pmap;
1042	vm_offset_t va;
1043	vm_page_t mpte;
1044{
1045	unsigned ptepindex;
1046	if (va >= UPT_MIN_ADDRESS)
1047		return 0;
1048
1049	if (mpte == NULL) {
1050		ptepindex = (va >> PDRSHIFT);
1051		if (pmap->pm_ptphint &&
1052			(pmap->pm_ptphint->pindex == ptepindex)) {
1053			mpte = pmap->pm_ptphint;
1054		} else {
1055			mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex);
1056			pmap->pm_ptphint = mpte;
1057		}
1058	}
1059
1060	return pmap_unwire_pte_hold(pmap, mpte);
1061}
1062
1063void
1064pmap_pinit0(pmap)
1065	struct pmap *pmap;
1066{
1067	pmap->pm_pdir =
1068		(pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE);
1069	pmap_kenter((vm_offset_t) pmap->pm_pdir, (vm_offset_t) IdlePTD);
1070	pmap->pm_count = 1;
1071	pmap->pm_active = 0;
1072	pmap->pm_ptphint = NULL;
1073	TAILQ_INIT(&pmap->pm_pvlist);
1074	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
1075	LIST_INSERT_HEAD(&allpmaps, pmap, pm_list);
1076}
1077
1078/*
1079 * Initialize a preallocated and zeroed pmap structure,
1080 * such as one in a vmspace structure.
1081 */
1082void
1083pmap_pinit(pmap)
1084	register struct pmap *pmap;
1085{
1086	vm_page_t ptdpg;
1087
1088	/*
1089	 * No need to allocate page table space yet but we do need a valid
1090	 * page directory table.
1091	 */
1092	if (pmap->pm_pdir == NULL)
1093		pmap->pm_pdir =
1094			(pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE);
1095
1096	/*
1097	 * allocate object for the ptes
1098	 */
1099	if (pmap->pm_pteobj == NULL)
1100		pmap->pm_pteobj = vm_object_allocate( OBJT_DEFAULT, PTDPTDI + 1);
1101
1102	/*
1103	 * allocate the page directory page
1104	 */
1105	ptdpg = vm_page_grab( pmap->pm_pteobj, PTDPTDI,
1106			VM_ALLOC_NORMAL | VM_ALLOC_RETRY);
1107
1108	ptdpg->wire_count = 1;
1109	++cnt.v_wire_count;
1110
1111
1112	vm_page_flag_clear(ptdpg, PG_MAPPED | PG_BUSY); /* not usually mapped*/
1113	ptdpg->valid = VM_PAGE_BITS_ALL;
1114
1115	pmap_kenter((vm_offset_t) pmap->pm_pdir, VM_PAGE_TO_PHYS(ptdpg));
1116	if ((ptdpg->flags & PG_ZERO) == 0)
1117		bzero(pmap->pm_pdir, PAGE_SIZE);
1118
1119	LIST_INSERT_HEAD(&allpmaps, pmap, pm_list);
1120	/* Wire in kernel global address entries. */
1121	/* XXX copies current process, does not fill in MPPTDI */
1122	bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE);
1123#ifdef SMP
1124	pmap->pm_pdir[MPPTDI] = PTD[MPPTDI];
1125#endif
1126
1127	/* install self-referential address mapping entry */
1128	*(unsigned *) (pmap->pm_pdir + PTDPTDI) =
1129		VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M;
1130
1131	pmap->pm_count = 1;
1132	pmap->pm_active = 0;
1133	pmap->pm_ptphint = NULL;
1134	TAILQ_INIT(&pmap->pm_pvlist);
1135	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
1136}
1137
1138/*
1139 * Wire in kernel global address entries.  To avoid a race condition
1140 * between pmap initialization and pmap_growkernel, this procedure
1141 * should be called after the vmspace is attached to the process
1142 * but before this pmap is activated.
1143 */
1144void
1145pmap_pinit2(pmap)
1146	struct pmap *pmap;
1147{
1148	/* XXX: Remove this stub when no longer called */
1149}
1150
1151static int
1152pmap_release_free_page(pmap, p)
1153	struct pmap *pmap;
1154	vm_page_t p;
1155{
1156	unsigned *pde = (unsigned *) pmap->pm_pdir;
1157	/*
1158	 * This code optimizes the case of freeing non-busy
1159	 * page-table pages.  Those pages are zero now, and
1160	 * might as well be placed directly into the zero queue.
1161	 */
1162	if (vm_page_sleep_busy(p, FALSE, "pmaprl"))
1163		return 0;
1164
1165	vm_page_busy(p);
1166
1167	/*
1168	 * Remove the page table page from the processes address space.
1169	 */
1170	pde[p->pindex] = 0;
1171	pmap->pm_stats.resident_count--;
1172
1173	if (p->hold_count)  {
1174		panic("pmap_release: freeing held page table page");
1175	}
1176	/*
1177	 * Page directory pages need to have the kernel
1178	 * stuff cleared, so they can go into the zero queue also.
1179	 */
1180	if (p->pindex == PTDPTDI) {
1181		bzero(pde + KPTDI, nkpt * PTESIZE);
1182#ifdef SMP
1183		pde[MPPTDI] = 0;
1184#endif
1185		pde[APTDPTDI] = 0;
1186		pmap_kremove((vm_offset_t) pmap->pm_pdir);
1187	}
1188
1189	if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex))
1190		pmap->pm_ptphint = NULL;
1191
1192	p->wire_count--;
1193	cnt.v_wire_count--;
1194	vm_page_free_zero(p);
1195	return 1;
1196}
1197
1198/*
1199 * this routine is called if the page table page is not
1200 * mapped correctly.
1201 */
1202static vm_page_t
1203_pmap_allocpte(pmap, ptepindex)
1204	pmap_t	pmap;
1205	unsigned ptepindex;
1206{
1207	vm_offset_t pteva, ptepa;
1208	vm_page_t m;
1209
1210	/*
1211	 * Find or fabricate a new pagetable page
1212	 */
1213	m = vm_page_grab(pmap->pm_pteobj, ptepindex,
1214			VM_ALLOC_ZERO | VM_ALLOC_RETRY);
1215
1216	KASSERT(m->queue == PQ_NONE,
1217		("_pmap_allocpte: %p->queue != PQ_NONE", m));
1218
1219	if (m->wire_count == 0)
1220		cnt.v_wire_count++;
1221	m->wire_count++;
1222
1223	/*
1224	 * Increment the hold count for the page table page
1225	 * (denoting a new mapping.)
1226	 */
1227	m->hold_count++;
1228
1229	/*
1230	 * Map the pagetable page into the process address space, if
1231	 * it isn't already there.
1232	 */
1233
1234	pmap->pm_stats.resident_count++;
1235
1236	ptepa = VM_PAGE_TO_PHYS(m);
1237	pmap->pm_pdir[ptepindex] =
1238		(pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M);
1239
1240	/*
1241	 * Set the page table hint
1242	 */
1243	pmap->pm_ptphint = m;
1244
1245	/*
1246	 * Try to use the new mapping, but if we cannot, then
1247	 * do it with the routine that maps the page explicitly.
1248	 */
1249	if ((m->flags & PG_ZERO) == 0) {
1250		if ((((unsigned)pmap->pm_pdir[PTDPTDI]) & PG_FRAME) ==
1251			(((unsigned) PTDpde) & PG_FRAME)) {
1252			pteva = UPT_MIN_ADDRESS + i386_ptob(ptepindex);
1253			bzero((caddr_t) pteva, PAGE_SIZE);
1254		} else {
1255			pmap_zero_page(ptepa);
1256		}
1257	}
1258
1259	m->valid = VM_PAGE_BITS_ALL;
1260	vm_page_flag_clear(m, PG_ZERO);
1261	vm_page_flag_set(m, PG_MAPPED);
1262	vm_page_wakeup(m);
1263
1264	return m;
1265}
1266
1267static vm_page_t
1268pmap_allocpte(pmap, va)
1269	pmap_t	pmap;
1270	vm_offset_t va;
1271{
1272	unsigned ptepindex;
1273	vm_offset_t ptepa;
1274	vm_page_t m;
1275
1276	/*
1277	 * Calculate pagetable page index
1278	 */
1279	ptepindex = va >> PDRSHIFT;
1280
1281	/*
1282	 * Get the page directory entry
1283	 */
1284	ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex];
1285
1286	/*
1287	 * This supports switching from a 4MB page to a
1288	 * normal 4K page.
1289	 */
1290	if (ptepa & PG_PS) {
1291		pmap->pm_pdir[ptepindex] = 0;
1292		ptepa = 0;
1293		invltlb();
1294	}
1295
1296	/*
1297	 * If the page table page is mapped, we just increment the
1298	 * hold count, and activate it.
1299	 */
1300	if (ptepa) {
1301		/*
1302		 * In order to get the page table page, try the
1303		 * hint first.
1304		 */
1305		if (pmap->pm_ptphint &&
1306			(pmap->pm_ptphint->pindex == ptepindex)) {
1307			m = pmap->pm_ptphint;
1308		} else {
1309			m = pmap_page_lookup( pmap->pm_pteobj, ptepindex);
1310			pmap->pm_ptphint = m;
1311		}
1312		m->hold_count++;
1313		return m;
1314	}
1315	/*
1316	 * Here if the pte page isn't mapped, or if it has been deallocated.
1317	 */
1318	return _pmap_allocpte(pmap, ptepindex);
1319}
1320
1321
1322/***************************************************
1323* Pmap allocation/deallocation routines.
1324 ***************************************************/
1325
1326/*
1327 * Release any resources held by the given physical map.
1328 * Called when a pmap initialized by pmap_pinit is being released.
1329 * Should only be called if the map contains no valid mappings.
1330 */
1331void
1332pmap_release(pmap)
1333	register struct pmap *pmap;
1334{
1335	vm_page_t p,n,ptdpg;
1336	vm_object_t object = pmap->pm_pteobj;
1337	int curgeneration;
1338
1339#if defined(DIAGNOSTIC)
1340	if (object->ref_count != 1)
1341		panic("pmap_release: pteobj reference count != 1");
1342#endif
1343
1344	ptdpg = NULL;
1345	LIST_REMOVE(pmap, pm_list);
1346retry:
1347	curgeneration = object->generation;
1348	for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) {
1349		n = TAILQ_NEXT(p, listq);
1350		if (p->pindex == PTDPTDI) {
1351			ptdpg = p;
1352			continue;
1353		}
1354		while (1) {
1355			if (!pmap_release_free_page(pmap, p) &&
1356				(object->generation != curgeneration))
1357				goto retry;
1358		}
1359	}
1360
1361	if (ptdpg && !pmap_release_free_page(pmap, ptdpg))
1362		goto retry;
1363}
1364
1365/*
1366 * grow the number of kernel page table entries, if needed
1367 */
1368void
1369pmap_growkernel(vm_offset_t addr)
1370{
1371	struct pmap *pmap;
1372	int s;
1373	vm_offset_t ptppaddr;
1374	vm_page_t nkpg;
1375	pd_entry_t newpdir;
1376
1377	s = splhigh();
1378	if (kernel_vm_end == 0) {
1379		kernel_vm_end = KERNBASE;
1380		nkpt = 0;
1381		while (pdir_pde(PTD, kernel_vm_end)) {
1382			kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
1383			nkpt++;
1384		}
1385	}
1386	addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
1387	while (kernel_vm_end < addr) {
1388		if (pdir_pde(PTD, kernel_vm_end)) {
1389			kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
1390			continue;
1391		}
1392
1393		/*
1394		 * This index is bogus, but out of the way
1395		 */
1396		nkpg = vm_page_alloc(kptobj, nkpt, VM_ALLOC_SYSTEM);
1397		if (!nkpg)
1398			panic("pmap_growkernel: no memory to grow kernel");
1399
1400		nkpt++;
1401
1402		vm_page_wire(nkpg);
1403		ptppaddr = VM_PAGE_TO_PHYS(nkpg);
1404		pmap_zero_page(ptppaddr);
1405		newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M);
1406		pdir_pde(PTD, kernel_vm_end) = newpdir;
1407
1408		LIST_FOREACH(pmap, &allpmaps, pm_list) {
1409			*pmap_pde(pmap, kernel_vm_end) = newpdir;
1410		}
1411		kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
1412	}
1413	splx(s);
1414}
1415
1416/*
1417 *	Retire the given physical map from service.
1418 *	Should only be called if the map contains
1419 *	no valid mappings.
1420 */
1421void
1422pmap_destroy(pmap)
1423	register pmap_t pmap;
1424{
1425	int count;
1426
1427	if (pmap == NULL)
1428		return;
1429
1430	count = --pmap->pm_count;
1431	if (count == 0) {
1432		pmap_release(pmap);
1433		panic("destroying a pmap is not yet implemented");
1434	}
1435}
1436
1437/*
1438 *	Add a reference to the specified pmap.
1439 */
1440void
1441pmap_reference(pmap)
1442	pmap_t pmap;
1443{
1444	if (pmap != NULL) {
1445		pmap->pm_count++;
1446	}
1447}
1448
1449/***************************************************
1450* page management routines.
1451 ***************************************************/
1452
1453/*
1454 * free the pv_entry back to the free list
1455 */
1456static PMAP_INLINE void
1457free_pv_entry(pv)
1458	pv_entry_t pv;
1459{
1460	pv_entry_count--;
1461	zfree(pvzone, pv);
1462}
1463
1464/*
1465 * get a new pv_entry, allocating a block from the system
1466 * when needed.
1467 * the memory allocation is performed bypassing the malloc code
1468 * because of the possibility of allocations at interrupt time.
1469 */
1470static pv_entry_t
1471get_pv_entry(void)
1472{
1473	pv_entry_count++;
1474	if (pv_entry_high_water &&
1475		(pv_entry_count > pv_entry_high_water) &&
1476		(pmap_pagedaemon_waken == 0)) {
1477		pmap_pagedaemon_waken = 1;
1478		wakeup (&vm_pages_needed);
1479	}
1480	return zalloc(pvzone);
1481}
1482
1483/*
1484 * This routine is very drastic, but can save the system
1485 * in a pinch.
1486 */
1487void
1488pmap_collect()
1489{
1490	int i;
1491	vm_page_t m;
1492	static int warningdone=0;
1493
1494	if (pmap_pagedaemon_waken == 0)
1495		return;
1496
1497	if (warningdone < 5) {
1498		printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n");
1499		warningdone++;
1500	}
1501
1502	for(i = 0; i < vm_page_array_size; i++) {
1503		m = &vm_page_array[i];
1504		if (m->wire_count || m->hold_count || m->busy ||
1505		    (m->flags & PG_BUSY))
1506			continue;
1507		pmap_remove_all(m);
1508	}
1509	pmap_pagedaemon_waken = 0;
1510}
1511
1512
1513/*
1514 * If it is the first entry on the list, it is actually
1515 * in the header and we must copy the following entry up
1516 * to the header.  Otherwise we must search the list for
1517 * the entry.  In either case we free the now unused entry.
1518 */
1519
1520static int
1521pmap_remove_entry(pmap, m, va)
1522	struct pmap *pmap;
1523	vm_page_t m;
1524	vm_offset_t va;
1525{
1526	pv_entry_t pv;
1527	int rtval;
1528	int s;
1529
1530	s = splvm();
1531	if (m->md.pv_list_count < pmap->pm_stats.resident_count) {
1532		for (pv = TAILQ_FIRST(&m->md.pv_list);
1533			pv;
1534			pv = TAILQ_NEXT(pv, pv_list)) {
1535			if (pmap == pv->pv_pmap && va == pv->pv_va)
1536				break;
1537		}
1538	} else {
1539		for (pv = TAILQ_FIRST(&pmap->pm_pvlist);
1540			pv;
1541			pv = TAILQ_NEXT(pv, pv_plist)) {
1542			if (va == pv->pv_va)
1543				break;
1544		}
1545	}
1546
1547	rtval = 0;
1548	if (pv) {
1549
1550		rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem);
1551		TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
1552		m->md.pv_list_count--;
1553		if (TAILQ_FIRST(&m->md.pv_list) == NULL)
1554			vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
1555
1556		TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist);
1557		free_pv_entry(pv);
1558	}
1559
1560	splx(s);
1561	return rtval;
1562}
1563
1564/*
1565 * Create a pv entry for page at pa for
1566 * (pmap, va).
1567 */
1568static void
1569pmap_insert_entry(pmap, va, mpte, m)
1570	pmap_t pmap;
1571	vm_offset_t va;
1572	vm_page_t mpte;
1573	vm_page_t m;
1574{
1575
1576	int s;
1577	pv_entry_t pv;
1578
1579	s = splvm();
1580	pv = get_pv_entry();
1581	pv->pv_va = va;
1582	pv->pv_pmap = pmap;
1583	pv->pv_ptem = mpte;
1584
1585	TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist);
1586	TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
1587	m->md.pv_list_count++;
1588
1589	splx(s);
1590}
1591
1592/*
1593 * pmap_remove_pte: do the things to unmap a page in a process
1594 */
1595static int
1596pmap_remove_pte(pmap, ptq, va)
1597	struct pmap *pmap;
1598	unsigned *ptq;
1599	vm_offset_t va;
1600{
1601	unsigned oldpte;
1602	vm_page_t m;
1603
1604	oldpte = atomic_readandclear_int(ptq);
1605	if (oldpte & PG_W)
1606		pmap->pm_stats.wired_count -= 1;
1607	/*
1608	 * Machines that don't support invlpg, also don't support
1609	 * PG_G.
1610	 */
1611	if (oldpte & PG_G)
1612		invlpg(va);
1613	pmap->pm_stats.resident_count -= 1;
1614	if (oldpte & PG_MANAGED) {
1615		m = PHYS_TO_VM_PAGE(oldpte);
1616		if (oldpte & PG_M) {
1617#if defined(PMAP_DIAGNOSTIC)
1618			if (pmap_nw_modified((pt_entry_t) oldpte)) {
1619				printf(
1620	"pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n",
1621				    va, oldpte);
1622			}
1623#endif
1624			if (pmap_track_modified(va))
1625				vm_page_dirty(m);
1626		}
1627		if (oldpte & PG_A)
1628			vm_page_flag_set(m, PG_REFERENCED);
1629		return pmap_remove_entry(pmap, m, va);
1630	} else {
1631		return pmap_unuse_pt(pmap, va, NULL);
1632	}
1633
1634	return 0;
1635}
1636
1637/*
1638 * Remove a single page from a process address space
1639 */
1640static void
1641pmap_remove_page(pmap, va)
1642	struct pmap *pmap;
1643	register vm_offset_t va;
1644{
1645	register unsigned *ptq;
1646
1647	/*
1648	 * if there is no pte for this address, just skip it!!!
1649	 */
1650	if (*pmap_pde(pmap, va) == 0) {
1651		return;
1652	}
1653
1654	/*
1655	 * get a local va for mappings for this pmap.
1656	 */
1657	ptq = get_ptbase(pmap) + i386_btop(va);
1658	if (*ptq) {
1659		(void) pmap_remove_pte(pmap, ptq, va);
1660		pmap_TLB_invalidate(pmap, va);
1661	}
1662	return;
1663}
1664
1665/*
1666 *	Remove the given range of addresses from the specified map.
1667 *
1668 *	It is assumed that the start and end are properly
1669 *	rounded to the page size.
1670 */
1671void
1672pmap_remove(pmap, sva, eva)
1673	struct pmap *pmap;
1674	register vm_offset_t sva;
1675	register vm_offset_t eva;
1676{
1677	register unsigned *ptbase;
1678	vm_offset_t pdnxt;
1679	vm_offset_t ptpaddr;
1680	vm_offset_t sindex, eindex;
1681	int anyvalid;
1682
1683	if (pmap == NULL)
1684		return;
1685
1686	if (pmap->pm_stats.resident_count == 0)
1687		return;
1688
1689	/*
1690	 * special handling of removing one page.  a very
1691	 * common operation and easy to short circuit some
1692	 * code.
1693	 */
1694	if (((sva + PAGE_SIZE) == eva) &&
1695		(((unsigned) pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) {
1696		pmap_remove_page(pmap, sva);
1697		return;
1698	}
1699
1700	anyvalid = 0;
1701
1702	/*
1703	 * Get a local virtual address for the mappings that are being
1704	 * worked with.
1705	 */
1706	ptbase = get_ptbase(pmap);
1707
1708	sindex = i386_btop(sva);
1709	eindex = i386_btop(eva);
1710
1711	for (; sindex < eindex; sindex = pdnxt) {
1712		unsigned pdirindex;
1713
1714		/*
1715		 * Calculate index for next page table.
1716		 */
1717		pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1));
1718		if (pmap->pm_stats.resident_count == 0)
1719			break;
1720
1721		pdirindex = sindex / NPDEPG;
1722		if (((ptpaddr = (unsigned) pmap->pm_pdir[pdirindex]) & PG_PS) != 0) {
1723			pmap->pm_pdir[pdirindex] = 0;
1724			pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
1725			anyvalid++;
1726			continue;
1727		}
1728
1729		/*
1730		 * Weed out invalid mappings. Note: we assume that the page
1731		 * directory table is always allocated, and in kernel virtual.
1732		 */
1733		if (ptpaddr == 0)
1734			continue;
1735
1736		/*
1737		 * Limit our scan to either the end of the va represented
1738		 * by the current page table page, or to the end of the
1739		 * range being removed.
1740		 */
1741		if (pdnxt > eindex) {
1742			pdnxt = eindex;
1743		}
1744
1745		for ( ;sindex != pdnxt; sindex++) {
1746			vm_offset_t va;
1747			if (ptbase[sindex] == 0) {
1748				continue;
1749			}
1750			va = i386_ptob(sindex);
1751
1752			anyvalid++;
1753			if (pmap_remove_pte(pmap,
1754				ptbase + sindex, va))
1755				break;
1756		}
1757	}
1758
1759	if (anyvalid)
1760		pmap_TLB_invalidate_all(pmap);
1761}
1762
1763/*
1764 *	Routine:	pmap_remove_all
1765 *	Function:
1766 *		Removes this physical page from
1767 *		all physical maps in which it resides.
1768 *		Reflects back modify bits to the pager.
1769 *
1770 *	Notes:
1771 *		Original versions of this routine were very
1772 *		inefficient because they iteratively called
1773 *		pmap_remove (slow...)
1774 */
1775
1776static void
1777pmap_remove_all(m)
1778	vm_page_t m;
1779{
1780	register pv_entry_t pv;
1781	register unsigned *pte, tpte;
1782	int s;
1783
1784#if defined(PMAP_DIAGNOSTIC)
1785	/*
1786	 * XXX this makes pmap_page_protect(NONE) illegal for non-managed
1787	 * pages!
1788	 */
1789	if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) {
1790		panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m));
1791	}
1792#endif
1793
1794	s = splvm();
1795	while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
1796		pv->pv_pmap->pm_stats.resident_count--;
1797
1798		pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
1799
1800		tpte = atomic_readandclear_int(pte);
1801		if (tpte & PG_W)
1802			pv->pv_pmap->pm_stats.wired_count--;
1803
1804		if (tpte & PG_A)
1805			vm_page_flag_set(m, PG_REFERENCED);
1806
1807		/*
1808		 * Update the vm_page_t clean and reference bits.
1809		 */
1810		if (tpte & PG_M) {
1811#if defined(PMAP_DIAGNOSTIC)
1812			if (pmap_nw_modified((pt_entry_t) tpte)) {
1813				printf(
1814	"pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n",
1815				    pv->pv_va, tpte);
1816			}
1817#endif
1818			if (pmap_track_modified(pv->pv_va))
1819				vm_page_dirty(m);
1820		}
1821		pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va);
1822
1823		TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist);
1824		TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
1825		m->md.pv_list_count--;
1826		pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem);
1827		free_pv_entry(pv);
1828	}
1829
1830	vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
1831
1832	splx(s);
1833}
1834
1835/*
1836 *	Set the physical protection on the
1837 *	specified range of this map as requested.
1838 */
1839void
1840pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
1841{
1842	register unsigned *ptbase;
1843	vm_offset_t pdnxt, ptpaddr;
1844	vm_pindex_t sindex, eindex;
1845	int anychanged;
1846
1847	if (pmap == NULL)
1848		return;
1849
1850	if ((prot & VM_PROT_READ) == VM_PROT_NONE) {
1851		pmap_remove(pmap, sva, eva);
1852		return;
1853	}
1854
1855	if (prot & VM_PROT_WRITE)
1856		return;
1857
1858	anychanged = 0;
1859
1860	ptbase = get_ptbase(pmap);
1861
1862	sindex = i386_btop(sva);
1863	eindex = i386_btop(eva);
1864
1865	for (; sindex < eindex; sindex = pdnxt) {
1866
1867		unsigned pdirindex;
1868
1869		pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1));
1870
1871		pdirindex = sindex / NPDEPG;
1872		if (((ptpaddr = (unsigned) pmap->pm_pdir[pdirindex]) & PG_PS) != 0) {
1873			(unsigned) pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW);
1874			pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
1875			anychanged++;
1876			continue;
1877		}
1878
1879		/*
1880		 * Weed out invalid mappings. Note: we assume that the page
1881		 * directory table is always allocated, and in kernel virtual.
1882		 */
1883		if (ptpaddr == 0)
1884			continue;
1885
1886		if (pdnxt > eindex) {
1887			pdnxt = eindex;
1888		}
1889
1890		for (; sindex != pdnxt; sindex++) {
1891
1892			unsigned pbits;
1893			vm_page_t m;
1894
1895			pbits = ptbase[sindex];
1896
1897			if (pbits & PG_MANAGED) {
1898				m = NULL;
1899				if (pbits & PG_A) {
1900					m = PHYS_TO_VM_PAGE(pbits);
1901					vm_page_flag_set(m, PG_REFERENCED);
1902					pbits &= ~PG_A;
1903				}
1904				if (pbits & PG_M) {
1905					if (pmap_track_modified(i386_ptob(sindex))) {
1906						if (m == NULL)
1907							m = PHYS_TO_VM_PAGE(pbits);
1908						vm_page_dirty(m);
1909						pbits &= ~PG_M;
1910					}
1911				}
1912			}
1913
1914			pbits &= ~PG_RW;
1915
1916			if (pbits != ptbase[sindex]) {
1917				ptbase[sindex] = pbits;
1918				anychanged = 1;
1919			}
1920		}
1921	}
1922	if (anychanged)
1923		pmap_TLB_invalidate_all(pmap);
1924}
1925
1926/*
1927 *	Insert the given physical page (p) at
1928 *	the specified virtual address (v) in the
1929 *	target physical map with the protection requested.
1930 *
1931 *	If specified, the page will be wired down, meaning
1932 *	that the related pte can not be reclaimed.
1933 *
1934 *	NB:  This is the only routine which MAY NOT lazy-evaluate
1935 *	or lose information.  That is, this routine must actually
1936 *	insert this page into the given map NOW.
1937 */
1938void
1939pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
1940	   boolean_t wired)
1941{
1942	vm_offset_t pa;
1943	register unsigned *pte;
1944	vm_offset_t opa;
1945	vm_offset_t origpte, newpte;
1946	vm_page_t mpte;
1947
1948	if (pmap == NULL)
1949		return;
1950
1951	va &= PG_FRAME;
1952#ifdef PMAP_DIAGNOSTIC
1953	if (va > VM_MAX_KERNEL_ADDRESS)
1954		panic("pmap_enter: toobig");
1955	if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS))
1956		panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va);
1957#endif
1958
1959	mpte = NULL;
1960	/*
1961	 * In the case that a page table page is not
1962	 * resident, we are creating it here.
1963	 */
1964	if (va < UPT_MIN_ADDRESS) {
1965		mpte = pmap_allocpte(pmap, va);
1966	}
1967#if 0 && defined(PMAP_DIAGNOSTIC)
1968	else {
1969		vm_offset_t *pdeaddr = (vm_offset_t *)pmap_pde(pmap, va);
1970		if (((origpte = (vm_offset_t) *pdeaddr) & PG_V) == 0) {
1971			panic("pmap_enter: invalid kernel page table page(0), pdir=%p, pde=%p, va=%p\n",
1972				pmap->pm_pdir[PTDPTDI], origpte, va);
1973		}
1974		if (smp_active) {
1975			pdeaddr = (vm_offset_t *) IdlePTDS[PCPU_GET(cpuid)];
1976			if (((newpte = pdeaddr[va >> PDRSHIFT]) & PG_V) == 0) {
1977				if ((vm_offset_t) my_idlePTD != (vm_offset_t) vtophys(pdeaddr))
1978					printf("pde mismatch: %x, %x\n", my_idlePTD, pdeaddr);
1979				printf("cpuid: %d, pdeaddr: 0x%x\n", PCPU_GET(cpuid), pdeaddr);
1980				panic("pmap_enter: invalid kernel page table page(1), pdir=%p, npde=%p, pde=%p, va=%p\n",
1981					pmap->pm_pdir[PTDPTDI], newpte, origpte, va);
1982			}
1983		}
1984	}
1985#endif
1986
1987	pte = pmap_pte(pmap, va);
1988
1989	/*
1990	 * Page Directory table entry not valid, we need a new PT page
1991	 */
1992	if (pte == NULL) {
1993		panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n",
1994			(void *)pmap->pm_pdir[PTDPTDI], va);
1995	}
1996
1997	pa = VM_PAGE_TO_PHYS(m) & PG_FRAME;
1998	origpte = *(vm_offset_t *)pte;
1999	opa = origpte & PG_FRAME;
2000
2001	if (origpte & PG_PS)
2002		panic("pmap_enter: attempted pmap_enter on 4MB page");
2003
2004	/*
2005	 * Mapping has not changed, must be protection or wiring change.
2006	 */
2007	if (origpte && (opa == pa)) {
2008		/*
2009		 * Wiring change, just update stats. We don't worry about
2010		 * wiring PT pages as they remain resident as long as there
2011		 * are valid mappings in them. Hence, if a user page is wired,
2012		 * the PT page will be also.
2013		 */
2014		if (wired && ((origpte & PG_W) == 0))
2015			pmap->pm_stats.wired_count++;
2016		else if (!wired && (origpte & PG_W))
2017			pmap->pm_stats.wired_count--;
2018
2019#if defined(PMAP_DIAGNOSTIC)
2020		if (pmap_nw_modified((pt_entry_t) origpte)) {
2021			printf(
2022	"pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n",
2023			    va, origpte);
2024		}
2025#endif
2026
2027		/*
2028		 * Remove extra pte reference
2029		 */
2030		if (mpte)
2031			mpte->hold_count--;
2032
2033		if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) {
2034			if ((origpte & PG_RW) == 0) {
2035				*pte |= PG_RW;
2036#ifdef SMP
2037				cpu_invlpg((void *)va);
2038				if (pmap->pm_active & PCPU_GET(other_cpus))
2039					smp_invltlb();
2040#else
2041				invltlb_1pg(va);
2042#endif
2043			}
2044			return;
2045		}
2046
2047		/*
2048		 * We might be turning off write access to the page,
2049		 * so we go ahead and sense modify status.
2050		 */
2051		if (origpte & PG_MANAGED) {
2052			if ((origpte & PG_M) && pmap_track_modified(va)) {
2053				vm_page_t om;
2054				om = PHYS_TO_VM_PAGE(opa);
2055				vm_page_dirty(om);
2056			}
2057			pa |= PG_MANAGED;
2058		}
2059		goto validate;
2060	}
2061	/*
2062	 * Mapping has changed, invalidate old range and fall through to
2063	 * handle validating new mapping.
2064	 */
2065	if (opa) {
2066		int err;
2067		err = pmap_remove_pte(pmap, pte, va);
2068		if (err)
2069			panic("pmap_enter: pte vanished, va: 0x%x", va);
2070	}
2071
2072	/*
2073	 * Enter on the PV list if part of our managed memory. Note that we
2074	 * raise IPL while manipulating pv_table since pmap_enter can be
2075	 * called at interrupt time.
2076	 */
2077	if (pmap_initialized &&
2078	    (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) {
2079		pmap_insert_entry(pmap, va, mpte, m);
2080		pa |= PG_MANAGED;
2081	}
2082
2083	/*
2084	 * Increment counters
2085	 */
2086	pmap->pm_stats.resident_count++;
2087	if (wired)
2088		pmap->pm_stats.wired_count++;
2089
2090validate:
2091	/*
2092	 * Now validate mapping with desired protection/wiring.
2093	 */
2094	newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V);
2095
2096	if (wired)
2097		newpte |= PG_W;
2098	if (va < UPT_MIN_ADDRESS)
2099		newpte |= PG_U;
2100	if (pmap == kernel_pmap)
2101		newpte |= pgeflag;
2102
2103	/*
2104	 * if the mapping or permission bits are different, we need
2105	 * to update the pte.
2106	 */
2107	if ((origpte & ~(PG_M|PG_A)) != newpte) {
2108		*pte = newpte | PG_A;
2109		/*if (origpte)*/ {
2110#ifdef SMP
2111			cpu_invlpg((void *)va);
2112			if (pmap->pm_active & PCPU_GET(other_cpus))
2113				smp_invltlb();
2114#else
2115			invltlb_1pg(va);
2116#endif
2117		}
2118	}
2119}
2120
2121/*
2122 * this code makes some *MAJOR* assumptions:
2123 * 1. Current pmap & pmap exists.
2124 * 2. Not wired.
2125 * 3. Read access.
2126 * 4. No page table pages.
2127 * 5. Tlbflush is deferred to calling procedure.
2128 * 6. Page IS managed.
2129 * but is *MUCH* faster than pmap_enter...
2130 */
2131
2132static vm_page_t
2133pmap_enter_quick(pmap, va, m, mpte)
2134	register pmap_t pmap;
2135	vm_offset_t va;
2136	vm_page_t m;
2137	vm_page_t mpte;
2138{
2139	unsigned *pte;
2140	vm_offset_t pa;
2141
2142	/*
2143	 * In the case that a page table page is not
2144	 * resident, we are creating it here.
2145	 */
2146	if (va < UPT_MIN_ADDRESS) {
2147		unsigned ptepindex;
2148		vm_offset_t ptepa;
2149
2150		/*
2151		 * Calculate pagetable page index
2152		 */
2153		ptepindex = va >> PDRSHIFT;
2154		if (mpte && (mpte->pindex == ptepindex)) {
2155			mpte->hold_count++;
2156		} else {
2157retry:
2158			/*
2159			 * Get the page directory entry
2160			 */
2161			ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex];
2162
2163			/*
2164			 * If the page table page is mapped, we just increment
2165			 * the hold count, and activate it.
2166			 */
2167			if (ptepa) {
2168				if (ptepa & PG_PS)
2169					panic("pmap_enter_quick: unexpected mapping into 4MB page");
2170				if (pmap->pm_ptphint &&
2171					(pmap->pm_ptphint->pindex == ptepindex)) {
2172					mpte = pmap->pm_ptphint;
2173				} else {
2174					mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex);
2175					pmap->pm_ptphint = mpte;
2176				}
2177				if (mpte == NULL)
2178					goto retry;
2179				mpte->hold_count++;
2180			} else {
2181				mpte = _pmap_allocpte(pmap, ptepindex);
2182			}
2183		}
2184	} else {
2185		mpte = NULL;
2186	}
2187
2188	/*
2189	 * This call to vtopte makes the assumption that we are
2190	 * entering the page into the current pmap.  In order to support
2191	 * quick entry into any pmap, one would likely use pmap_pte_quick.
2192	 * But that isn't as quick as vtopte.
2193	 */
2194	pte = (unsigned *)vtopte(va);
2195	if (*pte) {
2196		if (mpte)
2197			pmap_unwire_pte_hold(pmap, mpte);
2198		return 0;
2199	}
2200
2201	/*
2202	 * Enter on the PV list if part of our managed memory. Note that we
2203	 * raise IPL while manipulating pv_table since pmap_enter can be
2204	 * called at interrupt time.
2205	 */
2206	if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0)
2207		pmap_insert_entry(pmap, va, mpte, m);
2208
2209	/*
2210	 * Increment counters
2211	 */
2212	pmap->pm_stats.resident_count++;
2213
2214	pa = VM_PAGE_TO_PHYS(m);
2215
2216	/*
2217	 * Now validate mapping with RO protection
2218	 */
2219	if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED))
2220		*pte = pa | PG_V | PG_U;
2221	else
2222		*pte = pa | PG_V | PG_U | PG_MANAGED;
2223
2224	return mpte;
2225}
2226
2227/*
2228 * Make a temporary mapping for a physical address.  This is only intended
2229 * to be used for panic dumps.
2230 */
2231void *
2232pmap_kenter_temporary(vm_offset_t pa, int i)
2233{
2234	pmap_kenter((vm_offset_t)crashdumpmap + (i * PAGE_SIZE), pa);
2235	return ((void *)crashdumpmap);
2236}
2237
2238#define MAX_INIT_PT (96)
2239/*
2240 * pmap_object_init_pt preloads the ptes for a given object
2241 * into the specified pmap.  This eliminates the blast of soft
2242 * faults on process startup and immediately after an mmap.
2243 */
2244void
2245pmap_object_init_pt(pmap, addr, object, pindex, size, limit)
2246	pmap_t pmap;
2247	vm_offset_t addr;
2248	vm_object_t object;
2249	vm_pindex_t pindex;
2250	vm_size_t size;
2251	int limit;
2252{
2253	vm_offset_t tmpidx;
2254	int psize;
2255	vm_page_t p, mpte;
2256	int objpgs;
2257
2258	if (pmap == NULL || object == NULL)
2259		return;
2260
2261	/*
2262	 * This code maps large physical mmap regions into the
2263	 * processor address space.  Note that some shortcuts
2264	 * are taken, but the code works.
2265	 */
2266	if (pseflag &&
2267		(object->type == OBJT_DEVICE) &&
2268		((addr & (NBPDR - 1)) == 0) &&
2269		((size & (NBPDR - 1)) == 0) ) {
2270		int i;
2271		vm_page_t m[1];
2272		unsigned int ptepindex;
2273		int npdes;
2274		vm_offset_t ptepa;
2275
2276		if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)])
2277			return;
2278
2279retry:
2280		p = vm_page_lookup(object, pindex);
2281		if (p && vm_page_sleep_busy(p, FALSE, "init4p"))
2282			goto retry;
2283
2284		if (p == NULL) {
2285			p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL);
2286			if (p == NULL)
2287				return;
2288			m[0] = p;
2289
2290			if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) {
2291				vm_page_free(p);
2292				return;
2293			}
2294
2295			p = vm_page_lookup(object, pindex);
2296			vm_page_wakeup(p);
2297		}
2298
2299		ptepa = (vm_offset_t) VM_PAGE_TO_PHYS(p);
2300		if (ptepa & (NBPDR - 1)) {
2301			return;
2302		}
2303
2304		p->valid = VM_PAGE_BITS_ALL;
2305
2306		pmap->pm_stats.resident_count += size >> PAGE_SHIFT;
2307		npdes = size >> PDRSHIFT;
2308		for(i=0;i<npdes;i++) {
2309			pmap->pm_pdir[ptepindex] =
2310				(pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_PS);
2311			ptepa += NBPDR;
2312			ptepindex += 1;
2313		}
2314		vm_page_flag_set(p, PG_MAPPED);
2315		invltlb();
2316		return;
2317	}
2318
2319	psize = i386_btop(size);
2320
2321	if ((object->type != OBJT_VNODE) ||
2322		(limit && (psize > MAX_INIT_PT) &&
2323			(object->resident_page_count > MAX_INIT_PT))) {
2324		return;
2325	}
2326
2327	if (psize + pindex > object->size) {
2328		if (object->size < pindex)
2329			return;
2330		psize = object->size - pindex;
2331	}
2332
2333	mpte = NULL;
2334	/*
2335	 * if we are processing a major portion of the object, then scan the
2336	 * entire thing.
2337	 */
2338	if (psize > (object->resident_page_count >> 2)) {
2339		objpgs = psize;
2340
2341		for (p = TAILQ_FIRST(&object->memq);
2342		    ((objpgs > 0) && (p != NULL));
2343		    p = TAILQ_NEXT(p, listq)) {
2344
2345			tmpidx = p->pindex;
2346			if (tmpidx < pindex) {
2347				continue;
2348			}
2349			tmpidx -= pindex;
2350			if (tmpidx >= psize) {
2351				continue;
2352			}
2353			if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) &&
2354				(p->busy == 0) &&
2355			    (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) {
2356				if ((p->queue - p->pc) == PQ_CACHE)
2357					vm_page_deactivate(p);
2358				vm_page_busy(p);
2359				mpte = pmap_enter_quick(pmap,
2360					addr + i386_ptob(tmpidx), p, mpte);
2361				vm_page_flag_set(p, PG_MAPPED);
2362				vm_page_wakeup(p);
2363			}
2364			objpgs -= 1;
2365		}
2366	} else {
2367		/*
2368		 * else lookup the pages one-by-one.
2369		 */
2370		for (tmpidx = 0; tmpidx < psize; tmpidx += 1) {
2371			p = vm_page_lookup(object, tmpidx + pindex);
2372			if (p &&
2373			    ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) &&
2374				(p->busy == 0) &&
2375			    (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) {
2376				if ((p->queue - p->pc) == PQ_CACHE)
2377					vm_page_deactivate(p);
2378				vm_page_busy(p);
2379				mpte = pmap_enter_quick(pmap,
2380					addr + i386_ptob(tmpidx), p, mpte);
2381				vm_page_flag_set(p, PG_MAPPED);
2382				vm_page_wakeup(p);
2383			}
2384		}
2385	}
2386	return;
2387}
2388
2389/*
2390 * pmap_prefault provides a quick way of clustering
2391 * pagefaults into a processes address space.  It is a "cousin"
2392 * of pmap_object_init_pt, except it runs at page fault time instead
2393 * of mmap time.
2394 */
2395#define PFBAK 4
2396#define PFFOR 4
2397#define PAGEORDER_SIZE (PFBAK+PFFOR)
2398
2399static int pmap_prefault_pageorder[] = {
2400	-PAGE_SIZE, PAGE_SIZE,
2401	-2 * PAGE_SIZE, 2 * PAGE_SIZE,
2402	-3 * PAGE_SIZE, 3 * PAGE_SIZE
2403	-4 * PAGE_SIZE, 4 * PAGE_SIZE
2404};
2405
2406void
2407pmap_prefault(pmap, addra, entry)
2408	pmap_t pmap;
2409	vm_offset_t addra;
2410	vm_map_entry_t entry;
2411{
2412	int i;
2413	vm_offset_t starta;
2414	vm_offset_t addr;
2415	vm_pindex_t pindex;
2416	vm_page_t m, mpte;
2417	vm_object_t object;
2418
2419	if (!curproc || (pmap != vmspace_pmap(curproc->p_vmspace)))
2420		return;
2421
2422	object = entry->object.vm_object;
2423
2424	starta = addra - PFBAK * PAGE_SIZE;
2425	if (starta < entry->start) {
2426		starta = entry->start;
2427	} else if (starta > addra) {
2428		starta = 0;
2429	}
2430
2431	mpte = NULL;
2432	for (i = 0; i < PAGEORDER_SIZE; i++) {
2433		vm_object_t lobject;
2434		unsigned *pte;
2435
2436		addr = addra + pmap_prefault_pageorder[i];
2437		if (addr > addra + (PFFOR * PAGE_SIZE))
2438			addr = 0;
2439
2440		if (addr < starta || addr >= entry->end)
2441			continue;
2442
2443		if ((*pmap_pde(pmap, addr)) == NULL)
2444			continue;
2445
2446		pte = (unsigned *) vtopte(addr);
2447		if (*pte)
2448			continue;
2449
2450		pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT;
2451		lobject = object;
2452		for (m = vm_page_lookup(lobject, pindex);
2453		    (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object));
2454		    lobject = lobject->backing_object) {
2455			if (lobject->backing_object_offset & PAGE_MASK)
2456				break;
2457			pindex += (lobject->backing_object_offset >> PAGE_SHIFT);
2458			m = vm_page_lookup(lobject->backing_object, pindex);
2459		}
2460
2461		/*
2462		 * give-up when a page is not in memory
2463		 */
2464		if (m == NULL)
2465			break;
2466
2467		if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) &&
2468			(m->busy == 0) &&
2469		    (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) {
2470
2471			if ((m->queue - m->pc) == PQ_CACHE) {
2472				vm_page_deactivate(m);
2473			}
2474			vm_page_busy(m);
2475			mpte = pmap_enter_quick(pmap, addr, m, mpte);
2476			vm_page_flag_set(m, PG_MAPPED);
2477			vm_page_wakeup(m);
2478		}
2479	}
2480}
2481
2482/*
2483 *	Routine:	pmap_change_wiring
2484 *	Function:	Change the wiring attribute for a map/virtual-address
2485 *			pair.
2486 *	In/out conditions:
2487 *			The mapping must already exist in the pmap.
2488 */
2489void
2490pmap_change_wiring(pmap, va, wired)
2491	register pmap_t pmap;
2492	vm_offset_t va;
2493	boolean_t wired;
2494{
2495	register unsigned *pte;
2496
2497	if (pmap == NULL)
2498		return;
2499
2500	pte = pmap_pte(pmap, va);
2501
2502	if (wired && !pmap_pte_w(pte))
2503		pmap->pm_stats.wired_count++;
2504	else if (!wired && pmap_pte_w(pte))
2505		pmap->pm_stats.wired_count--;
2506
2507	/*
2508	 * Wiring is not a hardware characteristic so there is no need to
2509	 * invalidate TLB.
2510	 */
2511	pmap_pte_set_w(pte, wired);
2512}
2513
2514
2515
2516/*
2517 *	Copy the range specified by src_addr/len
2518 *	from the source map to the range dst_addr/len
2519 *	in the destination map.
2520 *
2521 *	This routine is only advisory and need not do anything.
2522 */
2523
2524void
2525pmap_copy(dst_pmap, src_pmap, dst_addr, len, src_addr)
2526	pmap_t dst_pmap, src_pmap;
2527	vm_offset_t dst_addr;
2528	vm_size_t len;
2529	vm_offset_t src_addr;
2530{
2531	vm_offset_t addr;
2532	vm_offset_t end_addr = src_addr + len;
2533	vm_offset_t pdnxt;
2534	unsigned src_frame, dst_frame;
2535	vm_page_t m;
2536
2537	if (dst_addr != src_addr)
2538		return;
2539
2540	src_frame = ((unsigned) src_pmap->pm_pdir[PTDPTDI]) & PG_FRAME;
2541	if (src_frame != (((unsigned) PTDpde) & PG_FRAME)) {
2542		return;
2543	}
2544
2545	dst_frame = ((unsigned) dst_pmap->pm_pdir[PTDPTDI]) & PG_FRAME;
2546	if (dst_frame != (((unsigned) APTDpde) & PG_FRAME)) {
2547		APTDpde = (pd_entry_t) (dst_frame | PG_RW | PG_V);
2548#if defined(SMP)
2549		/* The page directory is not shared between CPUs */
2550		cpu_invltlb();
2551#else
2552		invltlb();
2553#endif
2554	}
2555
2556	for(addr = src_addr; addr < end_addr; addr = pdnxt) {
2557		unsigned *src_pte, *dst_pte;
2558		vm_page_t dstmpte, srcmpte;
2559		vm_offset_t srcptepaddr;
2560		unsigned ptepindex;
2561
2562		if (addr >= UPT_MIN_ADDRESS)
2563			panic("pmap_copy: invalid to pmap_copy page tables\n");
2564
2565		/*
2566		 * Don't let optional prefaulting of pages make us go
2567		 * way below the low water mark of free pages or way
2568		 * above high water mark of used pv entries.
2569		 */
2570		if (cnt.v_free_count < cnt.v_free_reserved ||
2571		    pv_entry_count > pv_entry_high_water)
2572			break;
2573
2574		pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1));
2575		ptepindex = addr >> PDRSHIFT;
2576
2577		srcptepaddr = (vm_offset_t) src_pmap->pm_pdir[ptepindex];
2578		if (srcptepaddr == 0)
2579			continue;
2580
2581		if (srcptepaddr & PG_PS) {
2582			if (dst_pmap->pm_pdir[ptepindex] == 0) {
2583				dst_pmap->pm_pdir[ptepindex] = (pd_entry_t) srcptepaddr;
2584				dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE;
2585			}
2586			continue;
2587		}
2588
2589		srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex);
2590		if ((srcmpte == NULL) ||
2591			(srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY))
2592			continue;
2593
2594		if (pdnxt > end_addr)
2595			pdnxt = end_addr;
2596
2597		src_pte = (unsigned *) vtopte(addr);
2598		dst_pte = (unsigned *) avtopte(addr);
2599		while (addr < pdnxt) {
2600			unsigned ptetemp;
2601			ptetemp = *src_pte;
2602			/*
2603			 * we only virtual copy managed pages
2604			 */
2605			if ((ptetemp & PG_MANAGED) != 0) {
2606				/*
2607				 * We have to check after allocpte for the
2608				 * pte still being around...  allocpte can
2609				 * block.
2610				 */
2611				dstmpte = pmap_allocpte(dst_pmap, addr);
2612				if ((*dst_pte == 0) && (ptetemp = *src_pte)) {
2613					/*
2614					 * Clear the modified and
2615					 * accessed (referenced) bits
2616					 * during the copy.
2617					 */
2618					m = PHYS_TO_VM_PAGE(ptetemp);
2619					*dst_pte = ptetemp & ~(PG_M | PG_A);
2620					dst_pmap->pm_stats.resident_count++;
2621					pmap_insert_entry(dst_pmap, addr,
2622						dstmpte, m);
2623	 			} else {
2624					pmap_unwire_pte_hold(dst_pmap, dstmpte);
2625				}
2626				if (dstmpte->hold_count >= srcmpte->hold_count)
2627					break;
2628			}
2629			addr += PAGE_SIZE;
2630			src_pte++;
2631			dst_pte++;
2632		}
2633	}
2634}
2635
2636/*
2637 *	Routine:	pmap_kernel
2638 *	Function:
2639 *		Returns the physical map handle for the kernel.
2640 */
2641pmap_t
2642pmap_kernel()
2643{
2644	return (kernel_pmap);
2645}
2646
2647/*
2648 *	pmap_zero_page zeros the specified hardware page by mapping
2649 *	the page into KVM and using bzero to clear its contents.
2650 */
2651void
2652pmap_zero_page(phys)
2653	vm_offset_t phys;
2654{
2655
2656	if (*(int *) CMAP2)
2657		panic("pmap_zero_page: CMAP2 busy");
2658
2659	*(int *) CMAP2 = PG_V | PG_RW | (phys & PG_FRAME) | PG_A | PG_M;
2660	invltlb_1pg((vm_offset_t)CADDR2);
2661
2662#if defined(I686_CPU)
2663	if (cpu_class == CPUCLASS_686)
2664		i686_pagezero(CADDR2);
2665	else
2666#endif
2667		bzero(CADDR2, PAGE_SIZE);
2668	*(int *) CMAP2 = 0;
2669}
2670
2671/*
2672 *	pmap_zero_page_area zeros the specified hardware page by mapping
2673 *	the page into KVM and using bzero to clear its contents.
2674 *
2675 *	off and size may not cover an area beyond a single hardware page.
2676 */
2677void
2678pmap_zero_page_area(phys, off, size)
2679	vm_offset_t phys;
2680	int off;
2681	int size;
2682{
2683
2684	if (*(int *) CMAP2)
2685		panic("pmap_zero_page: CMAP2 busy");
2686
2687	*(int *) CMAP2 = PG_V | PG_RW | (phys & PG_FRAME) | PG_A | PG_M;
2688	invltlb_1pg((vm_offset_t)CADDR2);
2689
2690#if defined(I686_CPU)
2691	if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE)
2692		i686_pagezero(CADDR2);
2693	else
2694#endif
2695		bzero((char *)CADDR2 + off, size);
2696	*(int *) CMAP2 = 0;
2697}
2698
2699/*
2700 *	pmap_copy_page copies the specified (machine independent)
2701 *	page by mapping the page into virtual memory and using
2702 *	bcopy to copy the page, one machine dependent page at a
2703 *	time.
2704 */
2705void
2706pmap_copy_page(src, dst)
2707	vm_offset_t src;
2708	vm_offset_t dst;
2709{
2710
2711	if (*(int *) CMAP1)
2712		panic("pmap_copy_page: CMAP1 busy");
2713	if (*(int *) CMAP2)
2714		panic("pmap_copy_page: CMAP2 busy");
2715
2716	*(int *) CMAP1 = PG_V | (src & PG_FRAME) | PG_A;
2717	*(int *) CMAP2 = PG_V | PG_RW | (dst & PG_FRAME) | PG_A | PG_M;
2718#ifdef I386_CPU
2719	invltlb();
2720#else
2721	invlpg((u_int)CADDR1);
2722	invlpg((u_int)CADDR2);
2723#endif
2724
2725	bcopy(CADDR1, CADDR2, PAGE_SIZE);
2726
2727	*(int *) CMAP1 = 0;
2728	*(int *) CMAP2 = 0;
2729}
2730
2731
2732/*
2733 *	Routine:	pmap_pageable
2734 *	Function:
2735 *		Make the specified pages (by pmap, offset)
2736 *		pageable (or not) as requested.
2737 *
2738 *		A page which is not pageable may not take
2739 *		a fault; therefore, its page table entry
2740 *		must remain valid for the duration.
2741 *
2742 *		This routine is merely advisory; pmap_enter
2743 *		will specify that these pages are to be wired
2744 *		down (or not) as appropriate.
2745 */
2746void
2747pmap_pageable(pmap, sva, eva, pageable)
2748	pmap_t pmap;
2749	vm_offset_t sva, eva;
2750	boolean_t pageable;
2751{
2752}
2753
2754/*
2755 * this routine returns true if a physical page resides
2756 * in the given pmap.
2757 */
2758boolean_t
2759pmap_page_exists(pmap, m)
2760	pmap_t pmap;
2761	vm_page_t m;
2762{
2763	register pv_entry_t pv;
2764	int s;
2765
2766	if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
2767		return FALSE;
2768
2769	s = splvm();
2770
2771	/*
2772	 * Not found, check current mappings returning immediately if found.
2773	 */
2774	for (pv = TAILQ_FIRST(&m->md.pv_list);
2775		pv;
2776		pv = TAILQ_NEXT(pv, pv_list)) {
2777		if (pv->pv_pmap == pmap) {
2778			splx(s);
2779			return TRUE;
2780		}
2781	}
2782	splx(s);
2783	return (FALSE);
2784}
2785
2786#define PMAP_REMOVE_PAGES_CURPROC_ONLY
2787/*
2788 * Remove all pages from specified address space
2789 * this aids process exit speeds.  Also, this code
2790 * is special cased for current process only, but
2791 * can have the more generic (and slightly slower)
2792 * mode enabled.  This is much faster than pmap_remove
2793 * in the case of running down an entire address space.
2794 */
2795void
2796pmap_remove_pages(pmap, sva, eva)
2797	pmap_t pmap;
2798	vm_offset_t sva, eva;
2799{
2800	unsigned *pte, tpte;
2801	pv_entry_t pv, npv;
2802	int s;
2803	vm_page_t m;
2804
2805#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY
2806	if (!curproc || (pmap != vmspace_pmap(curproc->p_vmspace))) {
2807		printf("warning: pmap_remove_pages called with non-current pmap\n");
2808		return;
2809	}
2810#endif
2811
2812	s = splvm();
2813	for(pv = TAILQ_FIRST(&pmap->pm_pvlist);
2814		pv;
2815		pv = npv) {
2816
2817		if (pv->pv_va >= eva || pv->pv_va < sva) {
2818			npv = TAILQ_NEXT(pv, pv_plist);
2819			continue;
2820		}
2821
2822#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY
2823		pte = (unsigned *)vtopte(pv->pv_va);
2824#else
2825		pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
2826#endif
2827		tpte = *pte;
2828
2829/*
2830 * We cannot remove wired pages from a process' mapping at this time
2831 */
2832		if (tpte & PG_W) {
2833			npv = TAILQ_NEXT(pv, pv_plist);
2834			continue;
2835		}
2836		*pte = 0;
2837
2838		m = PHYS_TO_VM_PAGE(tpte);
2839
2840		KASSERT(m < &vm_page_array[vm_page_array_size],
2841			("pmap_remove_pages: bad tpte %x", tpte));
2842
2843		pv->pv_pmap->pm_stats.resident_count--;
2844
2845		/*
2846		 * Update the vm_page_t clean and reference bits.
2847		 */
2848		if (tpte & PG_M) {
2849			vm_page_dirty(m);
2850		}
2851
2852
2853		npv = TAILQ_NEXT(pv, pv_plist);
2854		TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist);
2855
2856		m->md.pv_list_count--;
2857		TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
2858		if (TAILQ_FIRST(&m->md.pv_list) == NULL) {
2859			vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
2860		}
2861
2862		pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem);
2863		free_pv_entry(pv);
2864	}
2865	splx(s);
2866	pmap_TLB_invalidate_all(pmap);
2867}
2868
2869/*
2870 * pmap_testbit tests bits in pte's
2871 * note that the testbit/changebit routines are inline,
2872 * and a lot of things compile-time evaluate.
2873 */
2874static boolean_t
2875pmap_testbit(m, bit)
2876	vm_page_t m;
2877	int bit;
2878{
2879	pv_entry_t pv;
2880	unsigned *pte;
2881	int s;
2882
2883	if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
2884		return FALSE;
2885
2886	if (TAILQ_FIRST(&m->md.pv_list) == NULL)
2887		return FALSE;
2888
2889	s = splvm();
2890
2891	for (pv = TAILQ_FIRST(&m->md.pv_list);
2892		pv;
2893		pv = TAILQ_NEXT(pv, pv_list)) {
2894
2895		/*
2896		 * if the bit being tested is the modified bit, then
2897		 * mark clean_map and ptes as never
2898		 * modified.
2899		 */
2900		if (bit & (PG_A|PG_M)) {
2901			if (!pmap_track_modified(pv->pv_va))
2902				continue;
2903		}
2904
2905#if defined(PMAP_DIAGNOSTIC)
2906		if (!pv->pv_pmap) {
2907			printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va);
2908			continue;
2909		}
2910#endif
2911		pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
2912		if (*pte & bit) {
2913			splx(s);
2914			return TRUE;
2915		}
2916	}
2917	splx(s);
2918	return (FALSE);
2919}
2920
2921/*
2922 * this routine is used to modify bits in ptes
2923 */
2924static __inline void
2925pmap_changebit(m, bit, setem)
2926	vm_page_t m;
2927	int bit;
2928	boolean_t setem;
2929{
2930	register pv_entry_t pv;
2931	register unsigned *pte;
2932	int s;
2933
2934	if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
2935		return;
2936
2937	s = splvm();
2938
2939	/*
2940	 * Loop over all current mappings setting/clearing as appropos If
2941	 * setting RO do we need to clear the VAC?
2942	 */
2943	for (pv = TAILQ_FIRST(&m->md.pv_list);
2944		pv;
2945		pv = TAILQ_NEXT(pv, pv_list)) {
2946
2947		/*
2948		 * don't write protect pager mappings
2949		 */
2950		if (!setem && (bit == PG_RW)) {
2951			if (!pmap_track_modified(pv->pv_va))
2952				continue;
2953		}
2954
2955#if defined(PMAP_DIAGNOSTIC)
2956		if (!pv->pv_pmap) {
2957			printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va);
2958			continue;
2959		}
2960#endif
2961
2962		pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
2963
2964		if (setem) {
2965			*(int *)pte |= bit;
2966			pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va);
2967		} else {
2968			vm_offset_t pbits = *(vm_offset_t *)pte;
2969			if (pbits & bit) {
2970				if (bit == PG_RW) {
2971					if (pbits & PG_M) {
2972						vm_page_dirty(m);
2973					}
2974					*(int *)pte = pbits & ~(PG_M|PG_RW);
2975				} else {
2976					*(int *)pte = pbits & ~bit;
2977				}
2978				pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va);
2979			}
2980		}
2981	}
2982	splx(s);
2983}
2984
2985/*
2986 *      pmap_page_protect:
2987 *
2988 *      Lower the permission for all mappings to a given page.
2989 */
2990void
2991pmap_page_protect(vm_page_t m, vm_prot_t prot)
2992{
2993	if ((prot & VM_PROT_WRITE) == 0) {
2994		if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) {
2995			pmap_changebit(m, PG_RW, FALSE);
2996		} else {
2997			pmap_remove_all(m);
2998		}
2999	}
3000}
3001
3002vm_offset_t
3003pmap_phys_address(ppn)
3004	int ppn;
3005{
3006	return (i386_ptob(ppn));
3007}
3008
3009/*
3010 *	pmap_ts_referenced:
3011 *
3012 *	Return the count of reference bits for a page, clearing all of them.
3013 */
3014int
3015pmap_ts_referenced(vm_page_t m)
3016{
3017	register pv_entry_t pv, pvf, pvn;
3018	unsigned *pte;
3019	int s;
3020	int rtval = 0;
3021
3022	if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
3023		return (rtval);
3024
3025	s = splvm();
3026
3027	if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
3028
3029		pvf = pv;
3030
3031		do {
3032			pvn = TAILQ_NEXT(pv, pv_list);
3033
3034			TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
3035
3036			TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
3037
3038			if (!pmap_track_modified(pv->pv_va))
3039				continue;
3040
3041			pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
3042
3043			if (pte && (*pte & PG_A)) {
3044				*pte &= ~PG_A;
3045
3046				pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va);
3047
3048				rtval++;
3049				if (rtval > 4) {
3050					break;
3051				}
3052			}
3053		} while ((pv = pvn) != NULL && pv != pvf);
3054	}
3055	splx(s);
3056
3057	return (rtval);
3058}
3059
3060/*
3061 *	pmap_is_modified:
3062 *
3063 *	Return whether or not the specified physical page was modified
3064 *	in any physical maps.
3065 */
3066boolean_t
3067pmap_is_modified(vm_page_t m)
3068{
3069	return pmap_testbit(m, PG_M);
3070}
3071
3072/*
3073 *	Clear the modify bits on the specified physical page.
3074 */
3075void
3076pmap_clear_modify(vm_page_t m)
3077{
3078	pmap_changebit(m, PG_M, FALSE);
3079}
3080
3081/*
3082 *	pmap_clear_reference:
3083 *
3084 *	Clear the reference bit on the specified physical page.
3085 */
3086void
3087pmap_clear_reference(vm_page_t m)
3088{
3089	pmap_changebit(m, PG_A, FALSE);
3090}
3091
3092/*
3093 * Miscellaneous support routines follow
3094 */
3095
3096static void
3097i386_protection_init()
3098{
3099	register int *kp, prot;
3100
3101	kp = protection_codes;
3102	for (prot = 0; prot < 8; prot++) {
3103		switch (prot) {
3104		case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE:
3105			/*
3106			 * Read access is also 0. There isn't any execute bit,
3107			 * so just make it readable.
3108			 */
3109		case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE:
3110		case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE:
3111		case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE:
3112			*kp++ = 0;
3113			break;
3114		case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE:
3115		case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE:
3116		case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE:
3117		case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE:
3118			*kp++ = PG_RW;
3119			break;
3120		}
3121	}
3122}
3123
3124/*
3125 * Map a set of physical memory pages into the kernel virtual
3126 * address space. Return a pointer to where it is mapped. This
3127 * routine is intended to be used for mapping device memory,
3128 * NOT real memory.
3129 */
3130void *
3131pmap_mapdev(pa, size)
3132	vm_offset_t pa;
3133	vm_size_t size;
3134{
3135	vm_offset_t va, tmpva, offset;
3136	unsigned *pte;
3137
3138	offset = pa & PAGE_MASK;
3139	size = roundup(offset + size, PAGE_SIZE);
3140
3141	va = kmem_alloc_pageable(kernel_map, size);
3142	if (!va)
3143		panic("pmap_mapdev: Couldn't alloc kernel virtual memory");
3144
3145	pa = pa & PG_FRAME;
3146	for (tmpva = va; size > 0;) {
3147		pte = (unsigned *)vtopte(tmpva);
3148		*pte = pa | PG_RW | PG_V | pgeflag;
3149		size -= PAGE_SIZE;
3150		tmpva += PAGE_SIZE;
3151		pa += PAGE_SIZE;
3152	}
3153	invltlb();
3154
3155	return ((void *)(va + offset));
3156}
3157
3158void
3159pmap_unmapdev(va, size)
3160	vm_offset_t va;
3161	vm_size_t size;
3162{
3163	vm_offset_t base, offset;
3164
3165	base = va & PG_FRAME;
3166	offset = va & PAGE_MASK;
3167	size = roundup(offset + size, PAGE_SIZE);
3168	kmem_free(kernel_map, base, size);
3169}
3170
3171/*
3172 * perform the pmap work for mincore
3173 */
3174int
3175pmap_mincore(pmap, addr)
3176	pmap_t pmap;
3177	vm_offset_t addr;
3178{
3179
3180	unsigned *ptep, pte;
3181	vm_page_t m;
3182	int val = 0;
3183
3184	ptep = pmap_pte(pmap, addr);
3185	if (ptep == 0) {
3186		return 0;
3187	}
3188
3189	if ((pte = *ptep) != 0) {
3190		vm_offset_t pa;
3191
3192		val = MINCORE_INCORE;
3193		if ((pte & PG_MANAGED) == 0)
3194			return val;
3195
3196		pa = pte & PG_FRAME;
3197
3198		m = PHYS_TO_VM_PAGE(pa);
3199
3200		/*
3201		 * Modified by us
3202		 */
3203		if (pte & PG_M)
3204			val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER;
3205		/*
3206		 * Modified by someone
3207		 */
3208		else if (m->dirty || pmap_is_modified(m))
3209			val |= MINCORE_MODIFIED_OTHER;
3210		/*
3211		 * Referenced by us
3212		 */
3213		if (pte & PG_A)
3214			val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER;
3215
3216		/*
3217		 * Referenced by someone
3218		 */
3219		else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) {
3220			val |= MINCORE_REFERENCED_OTHER;
3221			vm_page_flag_set(m, PG_REFERENCED);
3222		}
3223	}
3224	return val;
3225}
3226
3227void
3228pmap_activate(struct proc *p)
3229{
3230	pmap_t	pmap;
3231
3232	pmap = vmspace_pmap(p->p_vmspace);
3233#if defined(SMP)
3234	pmap->pm_active |= 1 << PCPU_GET(cpuid);
3235#else
3236	pmap->pm_active |= 1;
3237#endif
3238#if defined(SWTCH_OPTIM_STATS)
3239	tlb_flush_count++;
3240#endif
3241	load_cr3(p->p_addr->u_pcb.pcb_cr3 = vtophys(pmap->pm_pdir));
3242}
3243
3244vm_offset_t
3245pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size)
3246{
3247
3248	if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) {
3249		return addr;
3250	}
3251
3252	addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1);
3253	return addr;
3254}
3255
3256
3257#if defined(PMAP_DEBUG)
3258pmap_pid_dump(int pid)
3259{
3260	pmap_t pmap;
3261	struct proc *p;
3262	int npte = 0;
3263	int index;
3264	ALLPROC_LOCK(AP_SHARED);
3265	LIST_FOREACH(p, &allproc, p_list) {
3266		if (p->p_pid != pid)
3267			continue;
3268
3269		if (p->p_vmspace) {
3270			int i,j;
3271			index = 0;
3272			pmap = vmspace_pmap(p->p_vmspace);
3273			for(i=0;i<1024;i++) {
3274				pd_entry_t *pde;
3275				unsigned *pte;
3276				unsigned base = i << PDRSHIFT;
3277
3278				pde = &pmap->pm_pdir[i];
3279				if (pde && pmap_pde_v(pde)) {
3280					for(j=0;j<1024;j++) {
3281						unsigned va = base + (j << PAGE_SHIFT);
3282						if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) {
3283							if (index) {
3284								index = 0;
3285								printf("\n");
3286							}
3287							ALLPROC_LOCK(AP_RELEASE);
3288							return npte;
3289						}
3290						pte = pmap_pte_quick( pmap, va);
3291						if (pte && pmap_pte_v(pte)) {
3292							vm_offset_t pa;
3293							vm_page_t m;
3294							pa = *(int *)pte;
3295							m = PHYS_TO_VM_PAGE(pa);
3296							printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x",
3297								va, pa, m->hold_count, m->wire_count, m->flags);
3298							npte++;
3299							index++;
3300							if (index >= 2) {
3301								index = 0;
3302								printf("\n");
3303							} else {
3304								printf(" ");
3305							}
3306						}
3307					}
3308				}
3309			}
3310		}
3311	}
3312	ALLPROC_LOCK(AP_RELEASE);
3313	return npte;
3314}
3315#endif
3316
3317#if defined(DEBUG)
3318
3319static void	pads __P((pmap_t pm));
3320void		pmap_pvdump __P((vm_offset_t pa));
3321
3322/* print address space of pmap*/
3323static void
3324pads(pm)
3325	pmap_t pm;
3326{
3327	unsigned va, i, j;
3328	unsigned *ptep;
3329
3330	if (pm == kernel_pmap)
3331		return;
3332	for (i = 0; i < 1024; i++)
3333		if (pm->pm_pdir[i])
3334			for (j = 0; j < 1024; j++) {
3335				va = (i << PDRSHIFT) + (j << PAGE_SHIFT);
3336				if (pm == kernel_pmap && va < KERNBASE)
3337					continue;
3338				if (pm != kernel_pmap && va > UPT_MAX_ADDRESS)
3339					continue;
3340				ptep = pmap_pte_quick(pm, va);
3341				if (pmap_pte_v(ptep))
3342					printf("%x:%x ", va, *(int *) ptep);
3343			};
3344
3345}
3346
3347void
3348pmap_pvdump(pa)
3349	vm_offset_t pa;
3350{
3351	register pv_entry_t pv;
3352	vm_page_t m;
3353
3354	printf("pa %x", pa);
3355	m = PHYS_TO_VM_PAGE(pa);
3356	for (pv = TAILQ_FIRST(&m->md.pv_list);
3357		pv;
3358		pv = TAILQ_NEXT(pv, pv_list)) {
3359#ifdef used_to_be
3360		printf(" -> pmap %p, va %x, flags %x",
3361		    (void *)pv->pv_pmap, pv->pv_va, pv->pv_flags);
3362#endif
3363		printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va);
3364		pads(pv->pv_pmap);
3365	}
3366	printf(" ");
3367}
3368#endif
3369