pmap.c revision 71526
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 71526 2001-01-24 09:49:49Z jhb $
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#include "opt_user_ldt.h"
75
76#include <sys/param.h>
77#include <sys/systm.h>
78#include <sys/proc.h>
79#include <sys/msgbuf.h>
80#include <sys/vmmeter.h>
81#include <sys/mman.h>
82
83#include <vm/vm.h>
84#include <vm/vm_param.h>
85#include <sys/lock.h>
86#include <vm/vm_kern.h>
87#include <vm/vm_page.h>
88#include <vm/vm_map.h>
89#include <vm/vm_object.h>
90#include <vm/vm_extern.h>
91#include <vm/vm_pageout.h>
92#include <vm/vm_pager.h>
93#include <vm/vm_zone.h>
94
95#include <sys/user.h>
96
97#include <machine/cputypes.h>
98#include <machine/md_var.h>
99#include <machine/specialreg.h>
100#if defined(SMP) || defined(APIC_IO)
101#include <machine/smp.h>
102#include <machine/apic.h>
103#include <machine/segments.h>
104#include <machine/tss.h>
105#include <machine/globaldata.h>
106#endif /* SMP || APIC_IO */
107
108#define PMAP_KEEP_PDIRS
109#ifndef PMAP_SHPGPERPROC
110#define PMAP_SHPGPERPROC 200
111#endif
112
113#if defined(DIAGNOSTIC)
114#define PMAP_DIAGNOSTIC
115#endif
116
117#define MINPV 2048
118
119#if !defined(PMAP_DIAGNOSTIC)
120#define PMAP_INLINE __inline
121#else
122#define PMAP_INLINE
123#endif
124
125/*
126 * Get PDEs and PTEs for user/kernel address space
127 */
128#define	pmap_pde(m, v)	(&((m)->pm_pdir[(vm_offset_t)(v) >> PDRSHIFT]))
129#define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT])
130
131#define pmap_pde_v(pte)		((*(int *)pte & PG_V) != 0)
132#define pmap_pte_w(pte)		((*(int *)pte & PG_W) != 0)
133#define pmap_pte_m(pte)		((*(int *)pte & PG_M) != 0)
134#define pmap_pte_u(pte)		((*(int *)pte & PG_A) != 0)
135#define pmap_pte_v(pte)		((*(int *)pte & PG_V) != 0)
136
137#define pmap_pte_set_w(pte, v) ((v)?(*(int *)pte |= PG_W):(*(int *)pte &= ~PG_W))
138#define pmap_pte_set_prot(pte, v) ((*(int *)pte &= ~PG_PROT), (*(int *)pte |= (v)))
139
140/*
141 * Given a map and a machine independent protection code,
142 * convert to a vax protection code.
143 */
144#define pte_prot(m, p)	(protection_codes[p])
145static int protection_codes[8];
146
147static struct pmap kernel_pmap_store;
148pmap_t kernel_pmap;
149LIST_HEAD(pmaplist, pmap);
150struct pmaplist allpmaps;
151
152vm_offset_t avail_start;	/* PA of first available physical page */
153vm_offset_t avail_end;		/* PA of last available physical page */
154vm_offset_t virtual_avail;	/* VA of first avail page (after kernel bss) */
155vm_offset_t virtual_end;	/* VA of last avail page (end of kernel AS) */
156static boolean_t pmap_initialized = FALSE;	/* Has pmap_init completed? */
157static int pgeflag;		/* PG_G or-in */
158static int pseflag;		/* PG_PS or-in */
159
160static vm_object_t kptobj;
161
162static int nkpt;
163vm_offset_t kernel_vm_end;
164
165/*
166 * Data for the pv entry allocation mechanism
167 */
168static vm_zone_t pvzone;
169static struct vm_zone pvzone_store;
170static struct vm_object pvzone_obj;
171static int pv_entry_count=0, pv_entry_max=0, pv_entry_high_water=0;
172static int pmap_pagedaemon_waken = 0;
173static struct pv_entry *pvinit;
174
175/*
176 * All those kernel PT submaps that BSD is so fond of
177 */
178pt_entry_t *CMAP1 = 0;
179static pt_entry_t *CMAP2, *ptmmap;
180caddr_t CADDR1 = 0, ptvmmap = 0;
181static caddr_t CADDR2;
182static pt_entry_t *msgbufmap;
183struct msgbuf *msgbufp=0;
184
185/*
186 * Crashdump maps.
187 */
188static pt_entry_t *pt_crashdumpmap;
189static caddr_t crashdumpmap;
190
191#ifdef SMP
192extern pt_entry_t *SMPpt;
193#endif
194static pt_entry_t *PMAP1 = 0;
195static unsigned *PADDR1 = 0;
196
197static PMAP_INLINE void	free_pv_entry __P((pv_entry_t pv));
198static unsigned * get_ptbase __P((pmap_t pmap));
199static pv_entry_t get_pv_entry __P((void));
200static void	i386_protection_init __P((void));
201static __inline void	pmap_changebit __P((vm_page_t m, int bit, boolean_t setem));
202
203static void	pmap_remove_all __P((vm_page_t m));
204static vm_page_t pmap_enter_quick __P((pmap_t pmap, vm_offset_t va,
205				      vm_page_t m, vm_page_t mpte));
206static int pmap_remove_pte __P((struct pmap *pmap, unsigned *ptq,
207					vm_offset_t sva));
208static void pmap_remove_page __P((struct pmap *pmap, vm_offset_t va));
209static int pmap_remove_entry __P((struct pmap *pmap, vm_page_t m,
210					vm_offset_t va));
211static boolean_t pmap_testbit __P((vm_page_t m, int bit));
212static void pmap_insert_entry __P((pmap_t pmap, vm_offset_t va,
213		vm_page_t mpte, vm_page_t m));
214
215static vm_page_t pmap_allocpte __P((pmap_t pmap, vm_offset_t va));
216
217static int pmap_release_free_page __P((pmap_t pmap, vm_page_t p));
218static vm_page_t _pmap_allocpte __P((pmap_t pmap, unsigned ptepindex));
219static unsigned * pmap_pte_quick __P((pmap_t pmap, vm_offset_t va));
220static vm_page_t pmap_page_lookup __P((vm_object_t object, vm_pindex_t pindex));
221static int pmap_unuse_pt __P((pmap_t, vm_offset_t, vm_page_t));
222static vm_offset_t pmap_kmem_choose(vm_offset_t addr);
223
224static unsigned pdir4mb;
225
226/*
227 *	Routine:	pmap_pte
228 *	Function:
229 *		Extract the page table entry associated
230 *		with the given map/virtual_address pair.
231 */
232
233PMAP_INLINE unsigned *
234pmap_pte(pmap, va)
235	register pmap_t pmap;
236	vm_offset_t va;
237{
238	unsigned *pdeaddr;
239
240	if (pmap) {
241		pdeaddr = (unsigned *) pmap_pde(pmap, va);
242		if (*pdeaddr & PG_PS)
243			return pdeaddr;
244		if (*pdeaddr) {
245			return get_ptbase(pmap) + i386_btop(va);
246		}
247	}
248	return (0);
249}
250
251/*
252 * Move the kernel virtual free pointer to the next
253 * 4MB.  This is used to help improve performance
254 * by using a large (4MB) page for much of the kernel
255 * (.text, .data, .bss)
256 */
257static vm_offset_t
258pmap_kmem_choose(vm_offset_t addr)
259{
260	vm_offset_t newaddr = addr;
261#ifndef DISABLE_PSE
262	if (cpu_feature & CPUID_PSE) {
263		newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1);
264	}
265#endif
266	return newaddr;
267}
268
269/*
270 *	Bootstrap the system enough to run with virtual memory.
271 *
272 *	On the i386 this is called after mapping has already been enabled
273 *	and just syncs the pmap module with what has already been done.
274 *	[We can't call it easily with mapping off since the kernel is not
275 *	mapped with PA == VA, hence we would have to relocate every address
276 *	from the linked base (virtual) address "KERNBASE" to the actual
277 *	(physical) address starting relative to 0]
278 */
279void
280pmap_bootstrap(firstaddr, loadaddr)
281	vm_offset_t firstaddr;
282	vm_offset_t loadaddr;
283{
284	vm_offset_t va;
285	pt_entry_t *pte;
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	*(int *) PTD = 0;
365
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 *	For now, VM is already on, we only need to map the
716 *	specified memory.
717 */
718vm_offset_t
719pmap_map(virt, start, end, prot)
720	vm_offset_t virt;
721	vm_offset_t start;
722	vm_offset_t end;
723	int prot;
724{
725	while (start < end) {
726		pmap_kenter(virt, start);
727		virt += PAGE_SIZE;
728		start += PAGE_SIZE;
729	}
730	return (virt);
731}
732
733
734/*
735 * Add a list of wired pages to the kva
736 * this routine is only used for temporary
737 * kernel mappings that do not need to have
738 * page modification or references recorded.
739 * Note that old mappings are simply written
740 * over.  The page *must* be wired.
741 */
742void
743pmap_qenter(va, m, count)
744	vm_offset_t va;
745	vm_page_t *m;
746	int count;
747{
748	int i;
749
750	for (i = 0; i < count; i++) {
751		vm_offset_t tva = va + i * PAGE_SIZE;
752		pmap_kenter(tva, VM_PAGE_TO_PHYS(m[i]));
753	}
754}
755
756/*
757 * this routine jerks page mappings from the
758 * kernel -- it is meant only for temporary mappings.
759 */
760void
761pmap_qremove(va, count)
762	vm_offset_t va;
763	int count;
764{
765	vm_offset_t end_va;
766
767	end_va = va + count*PAGE_SIZE;
768
769	while (va < end_va) {
770		unsigned *pte;
771
772		pte = (unsigned *)vtopte(va);
773		*pte = 0;
774#ifdef SMP
775		cpu_invlpg((void *)va);
776#else
777		invltlb_1pg(va);
778#endif
779		va += PAGE_SIZE;
780	}
781#ifdef SMP
782	smp_invltlb();
783#endif
784}
785
786static vm_page_t
787pmap_page_lookup(object, pindex)
788	vm_object_t object;
789	vm_pindex_t pindex;
790{
791	vm_page_t m;
792retry:
793	m = vm_page_lookup(object, pindex);
794	if (m && vm_page_sleep_busy(m, FALSE, "pplookp"))
795		goto retry;
796	return m;
797}
798
799/*
800 * Create the UPAGES for a new process.
801 * This routine directly affects the fork perf for a process.
802 */
803void
804pmap_new_proc(p)
805	struct proc *p;
806{
807#ifdef I386_CPU
808	int updateneeded;
809#endif
810	int i;
811	vm_object_t upobj;
812	vm_page_t m;
813	struct user *up;
814	unsigned *ptek, oldpte;
815
816	/*
817	 * allocate object for the upages
818	 */
819	PROC_LOCK(p);
820	if ((upobj = p->p_upages_obj) == NULL) {
821		PROC_UNLOCK(p);
822		upobj = vm_object_allocate( OBJT_DEFAULT, UPAGES);
823		PROC_LOCK(p);
824		p->p_upages_obj = upobj;
825	}
826
827	/* get a kernel virtual address for the UPAGES for this proc */
828	if ((up = p->p_addr) == NULL) {
829		PROC_UNLOCK(p);
830		up = (struct user *) kmem_alloc_nofault(kernel_map,
831				UPAGES * PAGE_SIZE);
832		if (up == NULL)
833			panic("pmap_new_proc: u_map allocation failed");
834		PROC_LOCK(p);
835		p->p_addr = up;
836	}
837	PROC_UNLOCK(p);
838
839	ptek = (unsigned *) vtopte((vm_offset_t) up);
840
841#ifdef I386_CPU
842	updateneeded = 0;
843#endif
844	for(i=0;i<UPAGES;i++) {
845		/*
846		 * Get a kernel stack page
847		 */
848		m = vm_page_grab(upobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY);
849
850		/*
851		 * Wire the page
852		 */
853		m->wire_count++;
854		cnt.v_wire_count++;
855
856		oldpte = *(ptek + i);
857		/*
858		 * Enter the page into the kernel address space.
859		 */
860		*(ptek + i) = VM_PAGE_TO_PHYS(m) | PG_RW | PG_V | pgeflag;
861		if (oldpte) {
862#ifdef I386_CPU
863			updateneeded = 1;
864#else
865			invlpg((vm_offset_t) up + i * PAGE_SIZE);
866#endif
867		}
868
869		vm_page_wakeup(m);
870		vm_page_flag_clear(m, PG_ZERO);
871		vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE);
872		m->valid = VM_PAGE_BITS_ALL;
873	}
874#ifdef I386_CPU
875	if (updateneeded)
876		invltlb();
877#endif
878}
879
880/*
881 * Dispose the UPAGES for a process that has exited.
882 * This routine directly impacts the exit perf of a process.
883 */
884void
885pmap_dispose_proc(p)
886	struct proc *p;
887{
888	int i;
889	vm_object_t upobj;
890	vm_page_t m;
891	unsigned *ptek, oldpte;
892
893	upobj = p->p_upages_obj;
894
895	ptek = (unsigned *) vtopte((vm_offset_t) p->p_addr);
896	for(i=0;i<UPAGES;i++) {
897
898		if ((m = vm_page_lookup(upobj, i)) == NULL)
899			panic("pmap_dispose_proc: upage already missing???");
900
901		vm_page_busy(m);
902
903		oldpte = *(ptek + i);
904		*(ptek + i) = 0;
905#ifndef I386_CPU
906		invlpg((vm_offset_t) p->p_addr + i * PAGE_SIZE);
907#endif
908		vm_page_unwire(m, 0);
909		vm_page_free(m);
910	}
911#ifdef I386_CPU
912	invltlb();
913#endif
914}
915
916/*
917 * Allow the UPAGES for a process to be prejudicially paged out.
918 */
919void
920pmap_swapout_proc(p)
921	struct proc *p;
922{
923	int i;
924	vm_object_t upobj;
925	vm_page_t m;
926
927	upobj = p->p_upages_obj;
928	/*
929	 * let the upages be paged
930	 */
931	for(i=0;i<UPAGES;i++) {
932		if ((m = vm_page_lookup(upobj, i)) == NULL)
933			panic("pmap_swapout_proc: upage already missing???");
934		vm_page_dirty(m);
935		vm_page_unwire(m, 0);
936		pmap_kremove( (vm_offset_t) p->p_addr + PAGE_SIZE * i);
937	}
938}
939
940/*
941 * Bring the UPAGES for a specified process back in.
942 */
943void
944pmap_swapin_proc(p)
945	struct proc *p;
946{
947	int i,rv;
948	vm_object_t upobj;
949	vm_page_t m;
950
951	upobj = p->p_upages_obj;
952	for(i=0;i<UPAGES;i++) {
953
954		m = vm_page_grab(upobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY);
955
956		pmap_kenter(((vm_offset_t) p->p_addr) + i * PAGE_SIZE,
957			VM_PAGE_TO_PHYS(m));
958
959		if (m->valid != VM_PAGE_BITS_ALL) {
960			rv = vm_pager_get_pages(upobj, &m, 1, 0);
961			if (rv != VM_PAGER_OK)
962				panic("pmap_swapin_proc: cannot get upages for proc: %d\n", p->p_pid);
963			m = vm_page_lookup(upobj, i);
964			m->valid = VM_PAGE_BITS_ALL;
965		}
966
967		vm_page_wire(m);
968		vm_page_wakeup(m);
969		vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE);
970	}
971}
972
973/***************************************************
974 * Page table page management routines.....
975 ***************************************************/
976
977/*
978 * This routine unholds page table pages, and if the hold count
979 * drops to zero, then it decrements the wire count.
980 */
981static int
982_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) {
983
984	while (vm_page_sleep_busy(m, FALSE, "pmuwpt"))
985		;
986
987	if (m->hold_count == 0) {
988		vm_offset_t pteva;
989		/*
990		 * unmap the page table page
991		 */
992		pmap->pm_pdir[m->pindex] = 0;
993		--pmap->pm_stats.resident_count;
994		if ((((unsigned)pmap->pm_pdir[PTDPTDI]) & PG_FRAME) ==
995			(((unsigned) PTDpde) & PG_FRAME)) {
996			/*
997			 * Do a invltlb to make the invalidated mapping
998			 * take effect immediately.
999			 */
1000			pteva = UPT_MIN_ADDRESS + i386_ptob(m->pindex);
1001			pmap_TLB_invalidate(pmap, pteva);
1002		}
1003
1004		if (pmap->pm_ptphint == m)
1005			pmap->pm_ptphint = NULL;
1006
1007		/*
1008		 * If the page is finally unwired, simply free it.
1009		 */
1010		--m->wire_count;
1011		if (m->wire_count == 0) {
1012
1013			vm_page_flash(m);
1014			vm_page_busy(m);
1015			vm_page_free_zero(m);
1016			--cnt.v_wire_count;
1017		}
1018		return 1;
1019	}
1020	return 0;
1021}
1022
1023static PMAP_INLINE int
1024pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m)
1025{
1026	vm_page_unhold(m);
1027	if (m->hold_count == 0)
1028		return _pmap_unwire_pte_hold(pmap, m);
1029	else
1030		return 0;
1031}
1032
1033/*
1034 * After removing a page table entry, this routine is used to
1035 * conditionally free the page, and manage the hold/wire counts.
1036 */
1037static int
1038pmap_unuse_pt(pmap, va, mpte)
1039	pmap_t pmap;
1040	vm_offset_t va;
1041	vm_page_t mpte;
1042{
1043	unsigned ptepindex;
1044	if (va >= UPT_MIN_ADDRESS)
1045		return 0;
1046
1047	if (mpte == NULL) {
1048		ptepindex = (va >> PDRSHIFT);
1049		if (pmap->pm_ptphint &&
1050			(pmap->pm_ptphint->pindex == ptepindex)) {
1051			mpte = pmap->pm_ptphint;
1052		} else {
1053			mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex);
1054			pmap->pm_ptphint = mpte;
1055		}
1056	}
1057
1058	return pmap_unwire_pte_hold(pmap, mpte);
1059}
1060
1061void
1062pmap_pinit0(pmap)
1063	struct pmap *pmap;
1064{
1065	pmap->pm_pdir =
1066		(pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE);
1067	pmap_kenter((vm_offset_t) pmap->pm_pdir, (vm_offset_t) IdlePTD);
1068	pmap->pm_count = 1;
1069	pmap->pm_active = 0;
1070	pmap->pm_ptphint = NULL;
1071	TAILQ_INIT(&pmap->pm_pvlist);
1072	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
1073	LIST_INSERT_HEAD(&allpmaps, pmap, pm_list);
1074}
1075
1076/*
1077 * Initialize a preallocated and zeroed pmap structure,
1078 * such as one in a vmspace structure.
1079 */
1080void
1081pmap_pinit(pmap)
1082	register struct pmap *pmap;
1083{
1084	vm_page_t ptdpg;
1085
1086	/*
1087	 * No need to allocate page table space yet but we do need a valid
1088	 * page directory table.
1089	 */
1090	if (pmap->pm_pdir == NULL)
1091		pmap->pm_pdir =
1092			(pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE);
1093
1094	/*
1095	 * allocate object for the ptes
1096	 */
1097	if (pmap->pm_pteobj == NULL)
1098		pmap->pm_pteobj = vm_object_allocate( OBJT_DEFAULT, PTDPTDI + 1);
1099
1100	/*
1101	 * allocate the page directory page
1102	 */
1103	ptdpg = vm_page_grab( pmap->pm_pteobj, PTDPTDI,
1104			VM_ALLOC_NORMAL | VM_ALLOC_RETRY);
1105
1106	ptdpg->wire_count = 1;
1107	++cnt.v_wire_count;
1108
1109
1110	vm_page_flag_clear(ptdpg, PG_MAPPED | PG_BUSY); /* not usually mapped*/
1111	ptdpg->valid = VM_PAGE_BITS_ALL;
1112
1113	pmap_kenter((vm_offset_t) pmap->pm_pdir, VM_PAGE_TO_PHYS(ptdpg));
1114	if ((ptdpg->flags & PG_ZERO) == 0)
1115		bzero(pmap->pm_pdir, PAGE_SIZE);
1116
1117	LIST_INSERT_HEAD(&allpmaps, pmap, pm_list);
1118	/* Wire in kernel global address entries. */
1119	/* XXX copies current process, does not fill in MPPTDI */
1120	bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE);
1121#ifdef SMP
1122	pmap->pm_pdir[MPPTDI] = PTD[MPPTDI];
1123#endif
1124
1125	/* install self-referential address mapping entry */
1126	*(unsigned *) (pmap->pm_pdir + PTDPTDI) =
1127		VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M;
1128
1129	pmap->pm_count = 1;
1130	pmap->pm_active = 0;
1131	pmap->pm_ptphint = NULL;
1132	TAILQ_INIT(&pmap->pm_pvlist);
1133	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
1134}
1135
1136/*
1137 * Wire in kernel global address entries.  To avoid a race condition
1138 * between pmap initialization and pmap_growkernel, this procedure
1139 * should be called after the vmspace is attached to the process
1140 * but before this pmap is activated.
1141 */
1142void
1143pmap_pinit2(pmap)
1144	struct pmap *pmap;
1145{
1146	/* XXX: Remove this stub when no longer called */
1147}
1148
1149static int
1150pmap_release_free_page(pmap, p)
1151	struct pmap *pmap;
1152	vm_page_t p;
1153{
1154	unsigned *pde = (unsigned *) pmap->pm_pdir;
1155	/*
1156	 * This code optimizes the case of freeing non-busy
1157	 * page-table pages.  Those pages are zero now, and
1158	 * might as well be placed directly into the zero queue.
1159	 */
1160	if (vm_page_sleep_busy(p, FALSE, "pmaprl"))
1161		return 0;
1162
1163	vm_page_busy(p);
1164
1165	/*
1166	 * Remove the page table page from the processes address space.
1167	 */
1168	pde[p->pindex] = 0;
1169	pmap->pm_stats.resident_count--;
1170
1171	if (p->hold_count)  {
1172		panic("pmap_release: freeing held page table page");
1173	}
1174	/*
1175	 * Page directory pages need to have the kernel
1176	 * stuff cleared, so they can go into the zero queue also.
1177	 */
1178	if (p->pindex == PTDPTDI) {
1179		bzero(pde + KPTDI, nkpt * PTESIZE);
1180#ifdef SMP
1181		pde[MPPTDI] = 0;
1182#endif
1183		pde[APTDPTDI] = 0;
1184		pmap_kremove((vm_offset_t) pmap->pm_pdir);
1185	}
1186
1187	if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex))
1188		pmap->pm_ptphint = NULL;
1189
1190	p->wire_count--;
1191	cnt.v_wire_count--;
1192	vm_page_free_zero(p);
1193	return 1;
1194}
1195
1196/*
1197 * this routine is called if the page table page is not
1198 * mapped correctly.
1199 */
1200static vm_page_t
1201_pmap_allocpte(pmap, ptepindex)
1202	pmap_t	pmap;
1203	unsigned ptepindex;
1204{
1205	vm_offset_t pteva, ptepa;
1206	vm_page_t m;
1207
1208	/*
1209	 * Find or fabricate a new pagetable page
1210	 */
1211	m = vm_page_grab(pmap->pm_pteobj, ptepindex,
1212			VM_ALLOC_ZERO | VM_ALLOC_RETRY);
1213
1214	KASSERT(m->queue == PQ_NONE,
1215		("_pmap_allocpte: %p->queue != PQ_NONE", m));
1216
1217	if (m->wire_count == 0)
1218		cnt.v_wire_count++;
1219	m->wire_count++;
1220
1221	/*
1222	 * Increment the hold count for the page table page
1223	 * (denoting a new mapping.)
1224	 */
1225	m->hold_count++;
1226
1227	/*
1228	 * Map the pagetable page into the process address space, if
1229	 * it isn't already there.
1230	 */
1231
1232	pmap->pm_stats.resident_count++;
1233
1234	ptepa = VM_PAGE_TO_PHYS(m);
1235	pmap->pm_pdir[ptepindex] =
1236		(pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M);
1237
1238	/*
1239	 * Set the page table hint
1240	 */
1241	pmap->pm_ptphint = m;
1242
1243	/*
1244	 * Try to use the new mapping, but if we cannot, then
1245	 * do it with the routine that maps the page explicitly.
1246	 */
1247	if ((m->flags & PG_ZERO) == 0) {
1248		if ((((unsigned)pmap->pm_pdir[PTDPTDI]) & PG_FRAME) ==
1249			(((unsigned) PTDpde) & PG_FRAME)) {
1250			pteva = UPT_MIN_ADDRESS + i386_ptob(ptepindex);
1251			bzero((caddr_t) pteva, PAGE_SIZE);
1252		} else {
1253			pmap_zero_page(ptepa);
1254		}
1255	}
1256
1257	m->valid = VM_PAGE_BITS_ALL;
1258	vm_page_flag_clear(m, PG_ZERO);
1259	vm_page_flag_set(m, PG_MAPPED);
1260	vm_page_wakeup(m);
1261
1262	return m;
1263}
1264
1265static vm_page_t
1266pmap_allocpte(pmap, va)
1267	pmap_t	pmap;
1268	vm_offset_t va;
1269{
1270	unsigned ptepindex;
1271	vm_offset_t ptepa;
1272	vm_page_t m;
1273
1274	/*
1275	 * Calculate pagetable page index
1276	 */
1277	ptepindex = va >> PDRSHIFT;
1278
1279	/*
1280	 * Get the page directory entry
1281	 */
1282	ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex];
1283
1284	/*
1285	 * This supports switching from a 4MB page to a
1286	 * normal 4K page.
1287	 */
1288	if (ptepa & PG_PS) {
1289		pmap->pm_pdir[ptepindex] = 0;
1290		ptepa = 0;
1291		invltlb();
1292	}
1293
1294	/*
1295	 * If the page table page is mapped, we just increment the
1296	 * hold count, and activate it.
1297	 */
1298	if (ptepa) {
1299		/*
1300		 * In order to get the page table page, try the
1301		 * hint first.
1302		 */
1303		if (pmap->pm_ptphint &&
1304			(pmap->pm_ptphint->pindex == ptepindex)) {
1305			m = pmap->pm_ptphint;
1306		} else {
1307			m = pmap_page_lookup( pmap->pm_pteobj, ptepindex);
1308			pmap->pm_ptphint = m;
1309		}
1310		m->hold_count++;
1311		return m;
1312	}
1313	/*
1314	 * Here if the pte page isn't mapped, or if it has been deallocated.
1315	 */
1316	return _pmap_allocpte(pmap, ptepindex);
1317}
1318
1319
1320/***************************************************
1321* Pmap allocation/deallocation routines.
1322 ***************************************************/
1323
1324/*
1325 * Release any resources held by the given physical map.
1326 * Called when a pmap initialized by pmap_pinit is being released.
1327 * Should only be called if the map contains no valid mappings.
1328 */
1329void
1330pmap_release(pmap)
1331	register struct pmap *pmap;
1332{
1333	vm_page_t p,n,ptdpg;
1334	vm_object_t object = pmap->pm_pteobj;
1335	int curgeneration;
1336
1337#if defined(DIAGNOSTIC)
1338	if (object->ref_count != 1)
1339		panic("pmap_release: pteobj reference count != 1");
1340#endif
1341
1342	ptdpg = NULL;
1343	LIST_REMOVE(pmap, pm_list);
1344retry:
1345	curgeneration = object->generation;
1346	for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) {
1347		n = TAILQ_NEXT(p, listq);
1348		if (p->pindex == PTDPTDI) {
1349			ptdpg = p;
1350			continue;
1351		}
1352		while (1) {
1353			if (!pmap_release_free_page(pmap, p) &&
1354				(object->generation != curgeneration))
1355				goto retry;
1356		}
1357	}
1358
1359	if (ptdpg && !pmap_release_free_page(pmap, ptdpg))
1360		goto retry;
1361}
1362
1363/*
1364 * grow the number of kernel page table entries, if needed
1365 */
1366void
1367pmap_growkernel(vm_offset_t addr)
1368{
1369	struct pmap *pmap;
1370	int s;
1371	vm_offset_t ptppaddr;
1372	vm_page_t nkpg;
1373	pd_entry_t newpdir;
1374
1375	s = splhigh();
1376	if (kernel_vm_end == 0) {
1377		kernel_vm_end = KERNBASE;
1378		nkpt = 0;
1379		while (pdir_pde(PTD, kernel_vm_end)) {
1380			kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
1381			nkpt++;
1382		}
1383	}
1384	addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
1385	while (kernel_vm_end < addr) {
1386		if (pdir_pde(PTD, kernel_vm_end)) {
1387			kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
1388			continue;
1389		}
1390
1391		/*
1392		 * This index is bogus, but out of the way
1393		 */
1394		nkpg = vm_page_alloc(kptobj, nkpt, VM_ALLOC_SYSTEM);
1395		if (!nkpg)
1396			panic("pmap_growkernel: no memory to grow kernel");
1397
1398		nkpt++;
1399
1400		vm_page_wire(nkpg);
1401		ptppaddr = VM_PAGE_TO_PHYS(nkpg);
1402		pmap_zero_page(ptppaddr);
1403		newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M);
1404		pdir_pde(PTD, kernel_vm_end) = newpdir;
1405
1406		LIST_FOREACH(pmap, &allpmaps, pm_list) {
1407			*pmap_pde(pmap, kernel_vm_end) = newpdir;
1408		}
1409		kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
1410	}
1411	splx(s);
1412}
1413
1414/*
1415 *	Retire the given physical map from service.
1416 *	Should only be called if the map contains
1417 *	no valid mappings.
1418 */
1419void
1420pmap_destroy(pmap)
1421	register pmap_t pmap;
1422{
1423	int count;
1424
1425	if (pmap == NULL)
1426		return;
1427
1428	count = --pmap->pm_count;
1429	if (count == 0) {
1430		pmap_release(pmap);
1431		panic("destroying a pmap is not yet implemented");
1432	}
1433}
1434
1435/*
1436 *	Add a reference to the specified pmap.
1437 */
1438void
1439pmap_reference(pmap)
1440	pmap_t pmap;
1441{
1442	if (pmap != NULL) {
1443		pmap->pm_count++;
1444	}
1445}
1446
1447/***************************************************
1448* page management routines.
1449 ***************************************************/
1450
1451/*
1452 * free the pv_entry back to the free list
1453 */
1454static PMAP_INLINE void
1455free_pv_entry(pv)
1456	pv_entry_t pv;
1457{
1458	pv_entry_count--;
1459	zfree(pvzone, pv);
1460}
1461
1462/*
1463 * get a new pv_entry, allocating a block from the system
1464 * when needed.
1465 * the memory allocation is performed bypassing the malloc code
1466 * because of the possibility of allocations at interrupt time.
1467 */
1468static pv_entry_t
1469get_pv_entry(void)
1470{
1471	pv_entry_count++;
1472	if (pv_entry_high_water &&
1473		(pv_entry_count > pv_entry_high_water) &&
1474		(pmap_pagedaemon_waken == 0)) {
1475		pmap_pagedaemon_waken = 1;
1476		wakeup (&vm_pages_needed);
1477	}
1478	return zalloc(pvzone);
1479}
1480
1481/*
1482 * This routine is very drastic, but can save the system
1483 * in a pinch.
1484 */
1485void
1486pmap_collect()
1487{
1488	int i;
1489	vm_page_t m;
1490	static int warningdone=0;
1491
1492	if (pmap_pagedaemon_waken == 0)
1493		return;
1494
1495	if (warningdone < 5) {
1496		printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n");
1497		warningdone++;
1498	}
1499
1500	for(i = 0; i < vm_page_array_size; i++) {
1501		m = &vm_page_array[i];
1502		if (m->wire_count || m->hold_count || m->busy ||
1503		    (m->flags & PG_BUSY))
1504			continue;
1505		pmap_remove_all(m);
1506	}
1507	pmap_pagedaemon_waken = 0;
1508}
1509
1510
1511/*
1512 * If it is the first entry on the list, it is actually
1513 * in the header and we must copy the following entry up
1514 * to the header.  Otherwise we must search the list for
1515 * the entry.  In either case we free the now unused entry.
1516 */
1517
1518static int
1519pmap_remove_entry(pmap, m, va)
1520	struct pmap *pmap;
1521	vm_page_t m;
1522	vm_offset_t va;
1523{
1524	pv_entry_t pv;
1525	int rtval;
1526	int s;
1527
1528	s = splvm();
1529	if (m->md.pv_list_count < pmap->pm_stats.resident_count) {
1530		for (pv = TAILQ_FIRST(&m->md.pv_list);
1531			pv;
1532			pv = TAILQ_NEXT(pv, pv_list)) {
1533			if (pmap == pv->pv_pmap && va == pv->pv_va)
1534				break;
1535		}
1536	} else {
1537		for (pv = TAILQ_FIRST(&pmap->pm_pvlist);
1538			pv;
1539			pv = TAILQ_NEXT(pv, pv_plist)) {
1540			if (va == pv->pv_va)
1541				break;
1542		}
1543	}
1544
1545	rtval = 0;
1546	if (pv) {
1547
1548		rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem);
1549		TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
1550		m->md.pv_list_count--;
1551		if (TAILQ_FIRST(&m->md.pv_list) == NULL)
1552			vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
1553
1554		TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist);
1555		free_pv_entry(pv);
1556	}
1557
1558	splx(s);
1559	return rtval;
1560}
1561
1562/*
1563 * Create a pv entry for page at pa for
1564 * (pmap, va).
1565 */
1566static void
1567pmap_insert_entry(pmap, va, mpte, m)
1568	pmap_t pmap;
1569	vm_offset_t va;
1570	vm_page_t mpte;
1571	vm_page_t m;
1572{
1573
1574	int s;
1575	pv_entry_t pv;
1576
1577	s = splvm();
1578	pv = get_pv_entry();
1579	pv->pv_va = va;
1580	pv->pv_pmap = pmap;
1581	pv->pv_ptem = mpte;
1582
1583	TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist);
1584	TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
1585	m->md.pv_list_count++;
1586
1587	splx(s);
1588}
1589
1590/*
1591 * pmap_remove_pte: do the things to unmap a page in a process
1592 */
1593static int
1594pmap_remove_pte(pmap, ptq, va)
1595	struct pmap *pmap;
1596	unsigned *ptq;
1597	vm_offset_t va;
1598{
1599	unsigned oldpte;
1600	vm_page_t m;
1601
1602	oldpte = atomic_readandclear_int(ptq);
1603	if (oldpte & PG_W)
1604		pmap->pm_stats.wired_count -= 1;
1605	/*
1606	 * Machines that don't support invlpg, also don't support
1607	 * PG_G.
1608	 */
1609	if (oldpte & PG_G)
1610		invlpg(va);
1611	pmap->pm_stats.resident_count -= 1;
1612	if (oldpte & PG_MANAGED) {
1613		m = PHYS_TO_VM_PAGE(oldpte);
1614		if (oldpte & PG_M) {
1615#if defined(PMAP_DIAGNOSTIC)
1616			if (pmap_nw_modified((pt_entry_t) oldpte)) {
1617				printf(
1618	"pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n",
1619				    va, oldpte);
1620			}
1621#endif
1622			if (pmap_track_modified(va))
1623				vm_page_dirty(m);
1624		}
1625		if (oldpte & PG_A)
1626			vm_page_flag_set(m, PG_REFERENCED);
1627		return pmap_remove_entry(pmap, m, va);
1628	} else {
1629		return pmap_unuse_pt(pmap, va, NULL);
1630	}
1631
1632	return 0;
1633}
1634
1635/*
1636 * Remove a single page from a process address space
1637 */
1638static void
1639pmap_remove_page(pmap, va)
1640	struct pmap *pmap;
1641	register vm_offset_t va;
1642{
1643	register unsigned *ptq;
1644
1645	/*
1646	 * if there is no pte for this address, just skip it!!!
1647	 */
1648	if (*pmap_pde(pmap, va) == 0) {
1649		return;
1650	}
1651
1652	/*
1653	 * get a local va for mappings for this pmap.
1654	 */
1655	ptq = get_ptbase(pmap) + i386_btop(va);
1656	if (*ptq) {
1657		(void) pmap_remove_pte(pmap, ptq, va);
1658		pmap_TLB_invalidate(pmap, va);
1659	}
1660	return;
1661}
1662
1663/*
1664 *	Remove the given range of addresses from the specified map.
1665 *
1666 *	It is assumed that the start and end are properly
1667 *	rounded to the page size.
1668 */
1669void
1670pmap_remove(pmap, sva, eva)
1671	struct pmap *pmap;
1672	register vm_offset_t sva;
1673	register vm_offset_t eva;
1674{
1675	register unsigned *ptbase;
1676	vm_offset_t pdnxt;
1677	vm_offset_t ptpaddr;
1678	vm_offset_t sindex, eindex;
1679	int anyvalid;
1680
1681	if (pmap == NULL)
1682		return;
1683
1684	if (pmap->pm_stats.resident_count == 0)
1685		return;
1686
1687	/*
1688	 * special handling of removing one page.  a very
1689	 * common operation and easy to short circuit some
1690	 * code.
1691	 */
1692	if (((sva + PAGE_SIZE) == eva) &&
1693		(((unsigned) pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) {
1694		pmap_remove_page(pmap, sva);
1695		return;
1696	}
1697
1698	anyvalid = 0;
1699
1700	/*
1701	 * Get a local virtual address for the mappings that are being
1702	 * worked with.
1703	 */
1704	ptbase = get_ptbase(pmap);
1705
1706	sindex = i386_btop(sva);
1707	eindex = i386_btop(eva);
1708
1709	for (; sindex < eindex; sindex = pdnxt) {
1710		unsigned pdirindex;
1711
1712		/*
1713		 * Calculate index for next page table.
1714		 */
1715		pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1));
1716		if (pmap->pm_stats.resident_count == 0)
1717			break;
1718
1719		pdirindex = sindex / NPDEPG;
1720		if (((ptpaddr = (unsigned) pmap->pm_pdir[pdirindex]) & PG_PS) != 0) {
1721			pmap->pm_pdir[pdirindex] = 0;
1722			pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
1723			anyvalid++;
1724			continue;
1725		}
1726
1727		/*
1728		 * Weed out invalid mappings. Note: we assume that the page
1729		 * directory table is always allocated, and in kernel virtual.
1730		 */
1731		if (ptpaddr == 0)
1732			continue;
1733
1734		/*
1735		 * Limit our scan to either the end of the va represented
1736		 * by the current page table page, or to the end of the
1737		 * range being removed.
1738		 */
1739		if (pdnxt > eindex) {
1740			pdnxt = eindex;
1741		}
1742
1743		for ( ;sindex != pdnxt; sindex++) {
1744			vm_offset_t va;
1745			if (ptbase[sindex] == 0) {
1746				continue;
1747			}
1748			va = i386_ptob(sindex);
1749
1750			anyvalid++;
1751			if (pmap_remove_pte(pmap,
1752				ptbase + sindex, va))
1753				break;
1754		}
1755	}
1756
1757	if (anyvalid)
1758		pmap_TLB_invalidate_all(pmap);
1759}
1760
1761/*
1762 *	Routine:	pmap_remove_all
1763 *	Function:
1764 *		Removes this physical page from
1765 *		all physical maps in which it resides.
1766 *		Reflects back modify bits to the pager.
1767 *
1768 *	Notes:
1769 *		Original versions of this routine were very
1770 *		inefficient because they iteratively called
1771 *		pmap_remove (slow...)
1772 */
1773
1774static void
1775pmap_remove_all(m)
1776	vm_page_t m;
1777{
1778	register pv_entry_t pv;
1779	register unsigned *pte, tpte;
1780	int s;
1781
1782#if defined(PMAP_DIAGNOSTIC)
1783	/*
1784	 * XXX this makes pmap_page_protect(NONE) illegal for non-managed
1785	 * pages!
1786	 */
1787	if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) {
1788		panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m));
1789	}
1790#endif
1791
1792	s = splvm();
1793	while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
1794		pv->pv_pmap->pm_stats.resident_count--;
1795
1796		pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
1797
1798		tpte = atomic_readandclear_int(pte);
1799		if (tpte & PG_W)
1800			pv->pv_pmap->pm_stats.wired_count--;
1801
1802		if (tpte & PG_A)
1803			vm_page_flag_set(m, PG_REFERENCED);
1804
1805		/*
1806		 * Update the vm_page_t clean and reference bits.
1807		 */
1808		if (tpte & PG_M) {
1809#if defined(PMAP_DIAGNOSTIC)
1810			if (pmap_nw_modified((pt_entry_t) tpte)) {
1811				printf(
1812	"pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n",
1813				    pv->pv_va, tpte);
1814			}
1815#endif
1816			if (pmap_track_modified(pv->pv_va))
1817				vm_page_dirty(m);
1818		}
1819		pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va);
1820
1821		TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist);
1822		TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
1823		m->md.pv_list_count--;
1824		pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem);
1825		free_pv_entry(pv);
1826	}
1827
1828	vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
1829
1830	splx(s);
1831}
1832
1833/*
1834 *	Set the physical protection on the
1835 *	specified range of this map as requested.
1836 */
1837void
1838pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
1839{
1840	register unsigned *ptbase;
1841	vm_offset_t pdnxt, ptpaddr;
1842	vm_pindex_t sindex, eindex;
1843	int anychanged;
1844
1845	if (pmap == NULL)
1846		return;
1847
1848	if ((prot & VM_PROT_READ) == VM_PROT_NONE) {
1849		pmap_remove(pmap, sva, eva);
1850		return;
1851	}
1852
1853	if (prot & VM_PROT_WRITE)
1854		return;
1855
1856	anychanged = 0;
1857
1858	ptbase = get_ptbase(pmap);
1859
1860	sindex = i386_btop(sva);
1861	eindex = i386_btop(eva);
1862
1863	for (; sindex < eindex; sindex = pdnxt) {
1864
1865		unsigned pdirindex;
1866
1867		pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1));
1868
1869		pdirindex = sindex / NPDEPG;
1870		if (((ptpaddr = (unsigned) pmap->pm_pdir[pdirindex]) & PG_PS) != 0) {
1871			(unsigned) pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW);
1872			pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
1873			anychanged++;
1874			continue;
1875		}
1876
1877		/*
1878		 * Weed out invalid mappings. Note: we assume that the page
1879		 * directory table is always allocated, and in kernel virtual.
1880		 */
1881		if (ptpaddr == 0)
1882			continue;
1883
1884		if (pdnxt > eindex) {
1885			pdnxt = eindex;
1886		}
1887
1888		for (; sindex != pdnxt; sindex++) {
1889
1890			unsigned pbits;
1891			vm_page_t m;
1892
1893			pbits = ptbase[sindex];
1894
1895			if (pbits & PG_MANAGED) {
1896				m = NULL;
1897				if (pbits & PG_A) {
1898					m = PHYS_TO_VM_PAGE(pbits);
1899					vm_page_flag_set(m, PG_REFERENCED);
1900					pbits &= ~PG_A;
1901				}
1902				if (pbits & PG_M) {
1903					if (pmap_track_modified(i386_ptob(sindex))) {
1904						if (m == NULL)
1905							m = PHYS_TO_VM_PAGE(pbits);
1906						vm_page_dirty(m);
1907						pbits &= ~PG_M;
1908					}
1909				}
1910			}
1911
1912			pbits &= ~PG_RW;
1913
1914			if (pbits != ptbase[sindex]) {
1915				ptbase[sindex] = pbits;
1916				anychanged = 1;
1917			}
1918		}
1919	}
1920	if (anychanged)
1921		pmap_TLB_invalidate_all(pmap);
1922}
1923
1924/*
1925 *	Insert the given physical page (p) at
1926 *	the specified virtual address (v) in the
1927 *	target physical map with the protection requested.
1928 *
1929 *	If specified, the page will be wired down, meaning
1930 *	that the related pte can not be reclaimed.
1931 *
1932 *	NB:  This is the only routine which MAY NOT lazy-evaluate
1933 *	or lose information.  That is, this routine must actually
1934 *	insert this page into the given map NOW.
1935 */
1936void
1937pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
1938	   boolean_t wired)
1939{
1940	vm_offset_t pa;
1941	register unsigned *pte;
1942	vm_offset_t opa;
1943	vm_offset_t origpte, newpte;
1944	vm_page_t mpte;
1945
1946	if (pmap == NULL)
1947		return;
1948
1949	va &= PG_FRAME;
1950#ifdef PMAP_DIAGNOSTIC
1951	if (va > VM_MAX_KERNEL_ADDRESS)
1952		panic("pmap_enter: toobig");
1953	if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS))
1954		panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va);
1955#endif
1956
1957	mpte = NULL;
1958	/*
1959	 * In the case that a page table page is not
1960	 * resident, we are creating it here.
1961	 */
1962	if (va < UPT_MIN_ADDRESS) {
1963		mpte = pmap_allocpte(pmap, va);
1964	}
1965#if 0 && defined(PMAP_DIAGNOSTIC)
1966	else {
1967		vm_offset_t *pdeaddr = (vm_offset_t *)pmap_pde(pmap, va);
1968		if (((origpte = (vm_offset_t) *pdeaddr) & PG_V) == 0) {
1969			panic("pmap_enter: invalid kernel page table page(0), pdir=%p, pde=%p, va=%p\n",
1970				pmap->pm_pdir[PTDPTDI], origpte, va);
1971		}
1972		if (smp_active) {
1973			pdeaddr = (vm_offset_t *) IdlePTDS[PCPU_GET(cpuid)];
1974			if (((newpte = pdeaddr[va >> PDRSHIFT]) & PG_V) == 0) {
1975				if ((vm_offset_t) my_idlePTD != (vm_offset_t) vtophys(pdeaddr))
1976					printf("pde mismatch: %x, %x\n", my_idlePTD, pdeaddr);
1977				printf("cpuid: %d, pdeaddr: 0x%x\n", PCPU_GET(cpuid), pdeaddr);
1978				panic("pmap_enter: invalid kernel page table page(1), pdir=%p, npde=%p, pde=%p, va=%p\n",
1979					pmap->pm_pdir[PTDPTDI], newpte, origpte, va);
1980			}
1981		}
1982	}
1983#endif
1984
1985	pte = pmap_pte(pmap, va);
1986
1987	/*
1988	 * Page Directory table entry not valid, we need a new PT page
1989	 */
1990	if (pte == NULL) {
1991		panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n",
1992			(void *)pmap->pm_pdir[PTDPTDI], va);
1993	}
1994
1995	pa = VM_PAGE_TO_PHYS(m) & PG_FRAME;
1996	origpte = *(vm_offset_t *)pte;
1997	opa = origpte & PG_FRAME;
1998
1999	if (origpte & PG_PS)
2000		panic("pmap_enter: attempted pmap_enter on 4MB page");
2001
2002	/*
2003	 * Mapping has not changed, must be protection or wiring change.
2004	 */
2005	if (origpte && (opa == pa)) {
2006		/*
2007		 * Wiring change, just update stats. We don't worry about
2008		 * wiring PT pages as they remain resident as long as there
2009		 * are valid mappings in them. Hence, if a user page is wired,
2010		 * the PT page will be also.
2011		 */
2012		if (wired && ((origpte & PG_W) == 0))
2013			pmap->pm_stats.wired_count++;
2014		else if (!wired && (origpte & PG_W))
2015			pmap->pm_stats.wired_count--;
2016
2017#if defined(PMAP_DIAGNOSTIC)
2018		if (pmap_nw_modified((pt_entry_t) origpte)) {
2019			printf(
2020	"pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n",
2021			    va, origpte);
2022		}
2023#endif
2024
2025		/*
2026		 * Remove extra pte reference
2027		 */
2028		if (mpte)
2029			mpte->hold_count--;
2030
2031		if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) {
2032			if ((origpte & PG_RW) == 0) {
2033				*pte |= PG_RW;
2034#ifdef SMP
2035				cpu_invlpg((void *)va);
2036				if (pmap->pm_active & PCPU_GET(other_cpus))
2037					smp_invltlb();
2038#else
2039				invltlb_1pg(va);
2040#endif
2041			}
2042			return;
2043		}
2044
2045		/*
2046		 * We might be turning off write access to the page,
2047		 * so we go ahead and sense modify status.
2048		 */
2049		if (origpte & PG_MANAGED) {
2050			if ((origpte & PG_M) && pmap_track_modified(va)) {
2051				vm_page_t om;
2052				om = PHYS_TO_VM_PAGE(opa);
2053				vm_page_dirty(om);
2054			}
2055			pa |= PG_MANAGED;
2056		}
2057		goto validate;
2058	}
2059	/*
2060	 * Mapping has changed, invalidate old range and fall through to
2061	 * handle validating new mapping.
2062	 */
2063	if (opa) {
2064		int err;
2065		err = pmap_remove_pte(pmap, pte, va);
2066		if (err)
2067			panic("pmap_enter: pte vanished, va: 0x%x", va);
2068	}
2069
2070	/*
2071	 * Enter on the PV list if part of our managed memory. Note that we
2072	 * raise IPL while manipulating pv_table since pmap_enter can be
2073	 * called at interrupt time.
2074	 */
2075	if (pmap_initialized &&
2076	    (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) {
2077		pmap_insert_entry(pmap, va, mpte, m);
2078		pa |= PG_MANAGED;
2079	}
2080
2081	/*
2082	 * Increment counters
2083	 */
2084	pmap->pm_stats.resident_count++;
2085	if (wired)
2086		pmap->pm_stats.wired_count++;
2087
2088validate:
2089	/*
2090	 * Now validate mapping with desired protection/wiring.
2091	 */
2092	newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V);
2093
2094	if (wired)
2095		newpte |= PG_W;
2096	if (va < UPT_MIN_ADDRESS)
2097		newpte |= PG_U;
2098	if (pmap == kernel_pmap)
2099		newpte |= pgeflag;
2100
2101	/*
2102	 * if the mapping or permission bits are different, we need
2103	 * to update the pte.
2104	 */
2105	if ((origpte & ~(PG_M|PG_A)) != newpte) {
2106		*pte = newpte | PG_A;
2107		/*if (origpte)*/ {
2108#ifdef SMP
2109			cpu_invlpg((void *)va);
2110			if (pmap->pm_active & PCPU_GET(other_cpus))
2111				smp_invltlb();
2112#else
2113			invltlb_1pg(va);
2114#endif
2115		}
2116	}
2117}
2118
2119/*
2120 * this code makes some *MAJOR* assumptions:
2121 * 1. Current pmap & pmap exists.
2122 * 2. Not wired.
2123 * 3. Read access.
2124 * 4. No page table pages.
2125 * 5. Tlbflush is deferred to calling procedure.
2126 * 6. Page IS managed.
2127 * but is *MUCH* faster than pmap_enter...
2128 */
2129
2130static vm_page_t
2131pmap_enter_quick(pmap, va, m, mpte)
2132	register pmap_t pmap;
2133	vm_offset_t va;
2134	vm_page_t m;
2135	vm_page_t mpte;
2136{
2137	unsigned *pte;
2138	vm_offset_t pa;
2139
2140	/*
2141	 * In the case that a page table page is not
2142	 * resident, we are creating it here.
2143	 */
2144	if (va < UPT_MIN_ADDRESS) {
2145		unsigned ptepindex;
2146		vm_offset_t ptepa;
2147
2148		/*
2149		 * Calculate pagetable page index
2150		 */
2151		ptepindex = va >> PDRSHIFT;
2152		if (mpte && (mpte->pindex == ptepindex)) {
2153			mpte->hold_count++;
2154		} else {
2155retry:
2156			/*
2157			 * Get the page directory entry
2158			 */
2159			ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex];
2160
2161			/*
2162			 * If the page table page is mapped, we just increment
2163			 * the hold count, and activate it.
2164			 */
2165			if (ptepa) {
2166				if (ptepa & PG_PS)
2167					panic("pmap_enter_quick: unexpected mapping into 4MB page");
2168				if (pmap->pm_ptphint &&
2169					(pmap->pm_ptphint->pindex == ptepindex)) {
2170					mpte = pmap->pm_ptphint;
2171				} else {
2172					mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex);
2173					pmap->pm_ptphint = mpte;
2174				}
2175				if (mpte == NULL)
2176					goto retry;
2177				mpte->hold_count++;
2178			} else {
2179				mpte = _pmap_allocpte(pmap, ptepindex);
2180			}
2181		}
2182	} else {
2183		mpte = NULL;
2184	}
2185
2186	/*
2187	 * This call to vtopte makes the assumption that we are
2188	 * entering the page into the current pmap.  In order to support
2189	 * quick entry into any pmap, one would likely use pmap_pte_quick.
2190	 * But that isn't as quick as vtopte.
2191	 */
2192	pte = (unsigned *)vtopte(va);
2193	if (*pte) {
2194		if (mpte)
2195			pmap_unwire_pte_hold(pmap, mpte);
2196		return 0;
2197	}
2198
2199	/*
2200	 * Enter on the PV list if part of our managed memory. Note that we
2201	 * raise IPL while manipulating pv_table since pmap_enter can be
2202	 * called at interrupt time.
2203	 */
2204	if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0)
2205		pmap_insert_entry(pmap, va, mpte, m);
2206
2207	/*
2208	 * Increment counters
2209	 */
2210	pmap->pm_stats.resident_count++;
2211
2212	pa = VM_PAGE_TO_PHYS(m);
2213
2214	/*
2215	 * Now validate mapping with RO protection
2216	 */
2217	if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED))
2218		*pte = pa | PG_V | PG_U;
2219	else
2220		*pte = pa | PG_V | PG_U | PG_MANAGED;
2221
2222	return mpte;
2223}
2224
2225/*
2226 * Make a temporary mapping for a physical address.  This is only intended
2227 * to be used for panic dumps.
2228 */
2229void *
2230pmap_kenter_temporary(vm_offset_t pa, int i)
2231{
2232	pmap_kenter((vm_offset_t)crashdumpmap + (i * PAGE_SIZE), pa);
2233	return ((void *)crashdumpmap);
2234}
2235
2236#define MAX_INIT_PT (96)
2237/*
2238 * pmap_object_init_pt preloads the ptes for a given object
2239 * into the specified pmap.  This eliminates the blast of soft
2240 * faults on process startup and immediately after an mmap.
2241 */
2242void
2243pmap_object_init_pt(pmap, addr, object, pindex, size, limit)
2244	pmap_t pmap;
2245	vm_offset_t addr;
2246	vm_object_t object;
2247	vm_pindex_t pindex;
2248	vm_size_t size;
2249	int limit;
2250{
2251	vm_offset_t tmpidx;
2252	int psize;
2253	vm_page_t p, mpte;
2254	int objpgs;
2255
2256	if (pmap == NULL || object == NULL)
2257		return;
2258
2259	/*
2260	 * This code maps large physical mmap regions into the
2261	 * processor address space.  Note that some shortcuts
2262	 * are taken, but the code works.
2263	 */
2264	if (pseflag &&
2265		(object->type == OBJT_DEVICE) &&
2266		((addr & (NBPDR - 1)) == 0) &&
2267		((size & (NBPDR - 1)) == 0) ) {
2268		int i;
2269		vm_page_t m[1];
2270		unsigned int ptepindex;
2271		int npdes;
2272		vm_offset_t ptepa;
2273
2274		if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)])
2275			return;
2276
2277retry:
2278		p = vm_page_lookup(object, pindex);
2279		if (p && vm_page_sleep_busy(p, FALSE, "init4p"))
2280			goto retry;
2281
2282		if (p == NULL) {
2283			p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL);
2284			if (p == NULL)
2285				return;
2286			m[0] = p;
2287
2288			if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) {
2289				vm_page_free(p);
2290				return;
2291			}
2292
2293			p = vm_page_lookup(object, pindex);
2294			vm_page_wakeup(p);
2295		}
2296
2297		ptepa = (vm_offset_t) VM_PAGE_TO_PHYS(p);
2298		if (ptepa & (NBPDR - 1)) {
2299			return;
2300		}
2301
2302		p->valid = VM_PAGE_BITS_ALL;
2303
2304		pmap->pm_stats.resident_count += size >> PAGE_SHIFT;
2305		npdes = size >> PDRSHIFT;
2306		for(i=0;i<npdes;i++) {
2307			pmap->pm_pdir[ptepindex] =
2308				(pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_PS);
2309			ptepa += NBPDR;
2310			ptepindex += 1;
2311		}
2312		vm_page_flag_set(p, PG_MAPPED);
2313		invltlb();
2314		return;
2315	}
2316
2317	psize = i386_btop(size);
2318
2319	if ((object->type != OBJT_VNODE) ||
2320		(limit && (psize > MAX_INIT_PT) &&
2321			(object->resident_page_count > MAX_INIT_PT))) {
2322		return;
2323	}
2324
2325	if (psize + pindex > object->size) {
2326		if (object->size < pindex)
2327			return;
2328		psize = object->size - pindex;
2329	}
2330
2331	mpte = NULL;
2332	/*
2333	 * if we are processing a major portion of the object, then scan the
2334	 * entire thing.
2335	 */
2336	if (psize > (object->resident_page_count >> 2)) {
2337		objpgs = psize;
2338
2339		for (p = TAILQ_FIRST(&object->memq);
2340		    ((objpgs > 0) && (p != NULL));
2341		    p = TAILQ_NEXT(p, listq)) {
2342
2343			tmpidx = p->pindex;
2344			if (tmpidx < pindex) {
2345				continue;
2346			}
2347			tmpidx -= pindex;
2348			if (tmpidx >= psize) {
2349				continue;
2350			}
2351			if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) &&
2352				(p->busy == 0) &&
2353			    (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) {
2354				if ((p->queue - p->pc) == PQ_CACHE)
2355					vm_page_deactivate(p);
2356				vm_page_busy(p);
2357				mpte = pmap_enter_quick(pmap,
2358					addr + i386_ptob(tmpidx), p, mpte);
2359				vm_page_flag_set(p, PG_MAPPED);
2360				vm_page_wakeup(p);
2361			}
2362			objpgs -= 1;
2363		}
2364	} else {
2365		/*
2366		 * else lookup the pages one-by-one.
2367		 */
2368		for (tmpidx = 0; tmpidx < psize; tmpidx += 1) {
2369			p = vm_page_lookup(object, tmpidx + pindex);
2370			if (p &&
2371			    ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) &&
2372				(p->busy == 0) &&
2373			    (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) {
2374				if ((p->queue - p->pc) == PQ_CACHE)
2375					vm_page_deactivate(p);
2376				vm_page_busy(p);
2377				mpte = pmap_enter_quick(pmap,
2378					addr + i386_ptob(tmpidx), p, mpte);
2379				vm_page_flag_set(p, PG_MAPPED);
2380				vm_page_wakeup(p);
2381			}
2382		}
2383	}
2384	return;
2385}
2386
2387/*
2388 * pmap_prefault provides a quick way of clustering
2389 * pagefaults into a processes address space.  It is a "cousin"
2390 * of pmap_object_init_pt, except it runs at page fault time instead
2391 * of mmap time.
2392 */
2393#define PFBAK 4
2394#define PFFOR 4
2395#define PAGEORDER_SIZE (PFBAK+PFFOR)
2396
2397static int pmap_prefault_pageorder[] = {
2398	-PAGE_SIZE, PAGE_SIZE,
2399	-2 * PAGE_SIZE, 2 * PAGE_SIZE,
2400	-3 * PAGE_SIZE, 3 * PAGE_SIZE
2401	-4 * PAGE_SIZE, 4 * PAGE_SIZE
2402};
2403
2404void
2405pmap_prefault(pmap, addra, entry)
2406	pmap_t pmap;
2407	vm_offset_t addra;
2408	vm_map_entry_t entry;
2409{
2410	int i;
2411	vm_offset_t starta;
2412	vm_offset_t addr;
2413	vm_pindex_t pindex;
2414	vm_page_t m, mpte;
2415	vm_object_t object;
2416
2417	if (!curproc || (pmap != vmspace_pmap(curproc->p_vmspace)))
2418		return;
2419
2420	object = entry->object.vm_object;
2421
2422	starta = addra - PFBAK * PAGE_SIZE;
2423	if (starta < entry->start) {
2424		starta = entry->start;
2425	} else if (starta > addra) {
2426		starta = 0;
2427	}
2428
2429	mpte = NULL;
2430	for (i = 0; i < PAGEORDER_SIZE; i++) {
2431		vm_object_t lobject;
2432		unsigned *pte;
2433
2434		addr = addra + pmap_prefault_pageorder[i];
2435		if (addr > addra + (PFFOR * PAGE_SIZE))
2436			addr = 0;
2437
2438		if (addr < starta || addr >= entry->end)
2439			continue;
2440
2441		if ((*pmap_pde(pmap, addr)) == NULL)
2442			continue;
2443
2444		pte = (unsigned *) vtopte(addr);
2445		if (*pte)
2446			continue;
2447
2448		pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT;
2449		lobject = object;
2450		for (m = vm_page_lookup(lobject, pindex);
2451		    (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object));
2452		    lobject = lobject->backing_object) {
2453			if (lobject->backing_object_offset & PAGE_MASK)
2454				break;
2455			pindex += (lobject->backing_object_offset >> PAGE_SHIFT);
2456			m = vm_page_lookup(lobject->backing_object, pindex);
2457		}
2458
2459		/*
2460		 * give-up when a page is not in memory
2461		 */
2462		if (m == NULL)
2463			break;
2464
2465		if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) &&
2466			(m->busy == 0) &&
2467		    (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) {
2468
2469			if ((m->queue - m->pc) == PQ_CACHE) {
2470				vm_page_deactivate(m);
2471			}
2472			vm_page_busy(m);
2473			mpte = pmap_enter_quick(pmap, addr, m, mpte);
2474			vm_page_flag_set(m, PG_MAPPED);
2475			vm_page_wakeup(m);
2476		}
2477	}
2478}
2479
2480/*
2481 *	Routine:	pmap_change_wiring
2482 *	Function:	Change the wiring attribute for a map/virtual-address
2483 *			pair.
2484 *	In/out conditions:
2485 *			The mapping must already exist in the pmap.
2486 */
2487void
2488pmap_change_wiring(pmap, va, wired)
2489	register pmap_t pmap;
2490	vm_offset_t va;
2491	boolean_t wired;
2492{
2493	register unsigned *pte;
2494
2495	if (pmap == NULL)
2496		return;
2497
2498	pte = pmap_pte(pmap, va);
2499
2500	if (wired && !pmap_pte_w(pte))
2501		pmap->pm_stats.wired_count++;
2502	else if (!wired && pmap_pte_w(pte))
2503		pmap->pm_stats.wired_count--;
2504
2505	/*
2506	 * Wiring is not a hardware characteristic so there is no need to
2507	 * invalidate TLB.
2508	 */
2509	pmap_pte_set_w(pte, wired);
2510}
2511
2512
2513
2514/*
2515 *	Copy the range specified by src_addr/len
2516 *	from the source map to the range dst_addr/len
2517 *	in the destination map.
2518 *
2519 *	This routine is only advisory and need not do anything.
2520 */
2521
2522void
2523pmap_copy(dst_pmap, src_pmap, dst_addr, len, src_addr)
2524	pmap_t dst_pmap, src_pmap;
2525	vm_offset_t dst_addr;
2526	vm_size_t len;
2527	vm_offset_t src_addr;
2528{
2529	vm_offset_t addr;
2530	vm_offset_t end_addr = src_addr + len;
2531	vm_offset_t pdnxt;
2532	unsigned src_frame, dst_frame;
2533	vm_page_t m;
2534
2535	if (dst_addr != src_addr)
2536		return;
2537
2538	src_frame = ((unsigned) src_pmap->pm_pdir[PTDPTDI]) & PG_FRAME;
2539	if (src_frame != (((unsigned) PTDpde) & PG_FRAME)) {
2540		return;
2541	}
2542
2543	dst_frame = ((unsigned) dst_pmap->pm_pdir[PTDPTDI]) & PG_FRAME;
2544	if (dst_frame != (((unsigned) APTDpde) & PG_FRAME)) {
2545		APTDpde = (pd_entry_t) (dst_frame | PG_RW | PG_V);
2546#if defined(SMP)
2547		/* The page directory is not shared between CPUs */
2548		cpu_invltlb();
2549#else
2550		invltlb();
2551#endif
2552	}
2553
2554	for(addr = src_addr; addr < end_addr; addr = pdnxt) {
2555		unsigned *src_pte, *dst_pte;
2556		vm_page_t dstmpte, srcmpte;
2557		vm_offset_t srcptepaddr;
2558		unsigned ptepindex;
2559
2560		if (addr >= UPT_MIN_ADDRESS)
2561			panic("pmap_copy: invalid to pmap_copy page tables\n");
2562
2563		/*
2564		 * Don't let optional prefaulting of pages make us go
2565		 * way below the low water mark of free pages or way
2566		 * above high water mark of used pv entries.
2567		 */
2568		if (cnt.v_free_count < cnt.v_free_reserved ||
2569		    pv_entry_count > pv_entry_high_water)
2570			break;
2571
2572		pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1));
2573		ptepindex = addr >> PDRSHIFT;
2574
2575		srcptepaddr = (vm_offset_t) src_pmap->pm_pdir[ptepindex];
2576		if (srcptepaddr == 0)
2577			continue;
2578
2579		if (srcptepaddr & PG_PS) {
2580			if (dst_pmap->pm_pdir[ptepindex] == 0) {
2581				dst_pmap->pm_pdir[ptepindex] = (pd_entry_t) srcptepaddr;
2582				dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE;
2583			}
2584			continue;
2585		}
2586
2587		srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex);
2588		if ((srcmpte == NULL) ||
2589			(srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY))
2590			continue;
2591
2592		if (pdnxt > end_addr)
2593			pdnxt = end_addr;
2594
2595		src_pte = (unsigned *) vtopte(addr);
2596		dst_pte = (unsigned *) avtopte(addr);
2597		while (addr < pdnxt) {
2598			unsigned ptetemp;
2599			ptetemp = *src_pte;
2600			/*
2601			 * we only virtual copy managed pages
2602			 */
2603			if ((ptetemp & PG_MANAGED) != 0) {
2604				/*
2605				 * We have to check after allocpte for the
2606				 * pte still being around...  allocpte can
2607				 * block.
2608				 */
2609				dstmpte = pmap_allocpte(dst_pmap, addr);
2610				if ((*dst_pte == 0) && (ptetemp = *src_pte)) {
2611					/*
2612					 * Clear the modified and
2613					 * accessed (referenced) bits
2614					 * during the copy.
2615					 */
2616					m = PHYS_TO_VM_PAGE(ptetemp);
2617					*dst_pte = ptetemp & ~(PG_M | PG_A);
2618					dst_pmap->pm_stats.resident_count++;
2619					pmap_insert_entry(dst_pmap, addr,
2620						dstmpte, m);
2621	 			} else {
2622					pmap_unwire_pte_hold(dst_pmap, dstmpte);
2623				}
2624				if (dstmpte->hold_count >= srcmpte->hold_count)
2625					break;
2626			}
2627			addr += PAGE_SIZE;
2628			src_pte++;
2629			dst_pte++;
2630		}
2631	}
2632}
2633
2634/*
2635 *	Routine:	pmap_kernel
2636 *	Function:
2637 *		Returns the physical map handle for the kernel.
2638 */
2639pmap_t
2640pmap_kernel()
2641{
2642	return (kernel_pmap);
2643}
2644
2645/*
2646 *	pmap_zero_page zeros the specified hardware page by mapping
2647 *	the page into KVM and using bzero to clear its contents.
2648 */
2649void
2650pmap_zero_page(phys)
2651	vm_offset_t phys;
2652{
2653
2654	if (*(int *) CMAP2)
2655		panic("pmap_zero_page: CMAP2 busy");
2656
2657	*(int *) CMAP2 = PG_V | PG_RW | (phys & PG_FRAME) | PG_A | PG_M;
2658	invltlb_1pg((vm_offset_t)CADDR2);
2659
2660#if defined(I686_CPU)
2661	if (cpu_class == CPUCLASS_686)
2662		i686_pagezero(CADDR2);
2663	else
2664#endif
2665		bzero(CADDR2, PAGE_SIZE);
2666	*(int *) CMAP2 = 0;
2667}
2668
2669/*
2670 *	pmap_zero_page_area zeros the specified hardware page by mapping
2671 *	the page into KVM and using bzero to clear its contents.
2672 *
2673 *	off and size may not cover an area beyond a single hardware page.
2674 */
2675void
2676pmap_zero_page_area(phys, off, size)
2677	vm_offset_t phys;
2678	int off;
2679	int size;
2680{
2681
2682	if (*(int *) CMAP2)
2683		panic("pmap_zero_page: CMAP2 busy");
2684
2685	*(int *) CMAP2 = PG_V | PG_RW | (phys & PG_FRAME) | PG_A | PG_M;
2686	invltlb_1pg((vm_offset_t)CADDR2);
2687
2688#if defined(I686_CPU)
2689	if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE)
2690		i686_pagezero(CADDR2);
2691	else
2692#endif
2693		bzero((char *)CADDR2 + off, size);
2694	*(int *) CMAP2 = 0;
2695}
2696
2697/*
2698 *	pmap_copy_page copies the specified (machine independent)
2699 *	page by mapping the page into virtual memory and using
2700 *	bcopy to copy the page, one machine dependent page at a
2701 *	time.
2702 */
2703void
2704pmap_copy_page(src, dst)
2705	vm_offset_t src;
2706	vm_offset_t dst;
2707{
2708
2709	if (*(int *) CMAP1)
2710		panic("pmap_copy_page: CMAP1 busy");
2711	if (*(int *) CMAP2)
2712		panic("pmap_copy_page: CMAP2 busy");
2713
2714	*(int *) CMAP1 = PG_V | (src & PG_FRAME) | PG_A;
2715	*(int *) CMAP2 = PG_V | PG_RW | (dst & PG_FRAME) | PG_A | PG_M;
2716#ifdef I386_CPU
2717	invltlb();
2718#else
2719	invlpg((u_int)CADDR1);
2720	invlpg((u_int)CADDR2);
2721#endif
2722
2723	bcopy(CADDR1, CADDR2, PAGE_SIZE);
2724
2725	*(int *) CMAP1 = 0;
2726	*(int *) CMAP2 = 0;
2727}
2728
2729
2730/*
2731 *	Routine:	pmap_pageable
2732 *	Function:
2733 *		Make the specified pages (by pmap, offset)
2734 *		pageable (or not) as requested.
2735 *
2736 *		A page which is not pageable may not take
2737 *		a fault; therefore, its page table entry
2738 *		must remain valid for the duration.
2739 *
2740 *		This routine is merely advisory; pmap_enter
2741 *		will specify that these pages are to be wired
2742 *		down (or not) as appropriate.
2743 */
2744void
2745pmap_pageable(pmap, sva, eva, pageable)
2746	pmap_t pmap;
2747	vm_offset_t sva, eva;
2748	boolean_t pageable;
2749{
2750}
2751
2752/*
2753 * this routine returns true if a physical page resides
2754 * in the given pmap.
2755 */
2756boolean_t
2757pmap_page_exists(pmap, m)
2758	pmap_t pmap;
2759	vm_page_t m;
2760{
2761	register pv_entry_t pv;
2762	int s;
2763
2764	if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
2765		return FALSE;
2766
2767	s = splvm();
2768
2769	/*
2770	 * Not found, check current mappings returning immediately if found.
2771	 */
2772	for (pv = TAILQ_FIRST(&m->md.pv_list);
2773		pv;
2774		pv = TAILQ_NEXT(pv, pv_list)) {
2775		if (pv->pv_pmap == pmap) {
2776			splx(s);
2777			return TRUE;
2778		}
2779	}
2780	splx(s);
2781	return (FALSE);
2782}
2783
2784#define PMAP_REMOVE_PAGES_CURPROC_ONLY
2785/*
2786 * Remove all pages from specified address space
2787 * this aids process exit speeds.  Also, this code
2788 * is special cased for current process only, but
2789 * can have the more generic (and slightly slower)
2790 * mode enabled.  This is much faster than pmap_remove
2791 * in the case of running down an entire address space.
2792 */
2793void
2794pmap_remove_pages(pmap, sva, eva)
2795	pmap_t pmap;
2796	vm_offset_t sva, eva;
2797{
2798	unsigned *pte, tpte;
2799	pv_entry_t pv, npv;
2800	int s;
2801	vm_page_t m;
2802
2803#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY
2804	if (!curproc || (pmap != vmspace_pmap(curproc->p_vmspace))) {
2805		printf("warning: pmap_remove_pages called with non-current pmap\n");
2806		return;
2807	}
2808#endif
2809
2810	s = splvm();
2811	for(pv = TAILQ_FIRST(&pmap->pm_pvlist);
2812		pv;
2813		pv = npv) {
2814
2815		if (pv->pv_va >= eva || pv->pv_va < sva) {
2816			npv = TAILQ_NEXT(pv, pv_plist);
2817			continue;
2818		}
2819
2820#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY
2821		pte = (unsigned *)vtopte(pv->pv_va);
2822#else
2823		pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
2824#endif
2825		tpte = *pte;
2826
2827/*
2828 * We cannot remove wired pages from a process' mapping at this time
2829 */
2830		if (tpte & PG_W) {
2831			npv = TAILQ_NEXT(pv, pv_plist);
2832			continue;
2833		}
2834		*pte = 0;
2835
2836		m = PHYS_TO_VM_PAGE(tpte);
2837
2838		KASSERT(m < &vm_page_array[vm_page_array_size],
2839			("pmap_remove_pages: bad tpte %x", tpte));
2840
2841		pv->pv_pmap->pm_stats.resident_count--;
2842
2843		/*
2844		 * Update the vm_page_t clean and reference bits.
2845		 */
2846		if (tpte & PG_M) {
2847			vm_page_dirty(m);
2848		}
2849
2850
2851		npv = TAILQ_NEXT(pv, pv_plist);
2852		TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist);
2853
2854		m->md.pv_list_count--;
2855		TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
2856		if (TAILQ_FIRST(&m->md.pv_list) == NULL) {
2857			vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
2858		}
2859
2860		pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem);
2861		free_pv_entry(pv);
2862	}
2863	splx(s);
2864	pmap_TLB_invalidate_all(pmap);
2865}
2866
2867/*
2868 * pmap_testbit tests bits in pte's
2869 * note that the testbit/changebit routines are inline,
2870 * and a lot of things compile-time evaluate.
2871 */
2872static boolean_t
2873pmap_testbit(m, bit)
2874	vm_page_t m;
2875	int bit;
2876{
2877	pv_entry_t pv;
2878	unsigned *pte;
2879	int s;
2880
2881	if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
2882		return FALSE;
2883
2884	if (TAILQ_FIRST(&m->md.pv_list) == NULL)
2885		return FALSE;
2886
2887	s = splvm();
2888
2889	for (pv = TAILQ_FIRST(&m->md.pv_list);
2890		pv;
2891		pv = TAILQ_NEXT(pv, pv_list)) {
2892
2893		/*
2894		 * if the bit being tested is the modified bit, then
2895		 * mark clean_map and ptes as never
2896		 * modified.
2897		 */
2898		if (bit & (PG_A|PG_M)) {
2899			if (!pmap_track_modified(pv->pv_va))
2900				continue;
2901		}
2902
2903#if defined(PMAP_DIAGNOSTIC)
2904		if (!pv->pv_pmap) {
2905			printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va);
2906			continue;
2907		}
2908#endif
2909		pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
2910		if (*pte & bit) {
2911			splx(s);
2912			return TRUE;
2913		}
2914	}
2915	splx(s);
2916	return (FALSE);
2917}
2918
2919/*
2920 * this routine is used to modify bits in ptes
2921 */
2922static __inline void
2923pmap_changebit(m, bit, setem)
2924	vm_page_t m;
2925	int bit;
2926	boolean_t setem;
2927{
2928	register pv_entry_t pv;
2929	register unsigned *pte;
2930	int s;
2931
2932	if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
2933		return;
2934
2935	s = splvm();
2936
2937	/*
2938	 * Loop over all current mappings setting/clearing as appropos If
2939	 * setting RO do we need to clear the VAC?
2940	 */
2941	for (pv = TAILQ_FIRST(&m->md.pv_list);
2942		pv;
2943		pv = TAILQ_NEXT(pv, pv_list)) {
2944
2945		/*
2946		 * don't write protect pager mappings
2947		 */
2948		if (!setem && (bit == PG_RW)) {
2949			if (!pmap_track_modified(pv->pv_va))
2950				continue;
2951		}
2952
2953#if defined(PMAP_DIAGNOSTIC)
2954		if (!pv->pv_pmap) {
2955			printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va);
2956			continue;
2957		}
2958#endif
2959
2960		pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
2961
2962		if (setem) {
2963			*(int *)pte |= bit;
2964			pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va);
2965		} else {
2966			vm_offset_t pbits = *(vm_offset_t *)pte;
2967			if (pbits & bit) {
2968				if (bit == PG_RW) {
2969					if (pbits & PG_M) {
2970						vm_page_dirty(m);
2971					}
2972					*(int *)pte = pbits & ~(PG_M|PG_RW);
2973				} else {
2974					*(int *)pte = pbits & ~bit;
2975				}
2976				pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va);
2977			}
2978		}
2979	}
2980	splx(s);
2981}
2982
2983/*
2984 *      pmap_page_protect:
2985 *
2986 *      Lower the permission for all mappings to a given page.
2987 */
2988void
2989pmap_page_protect(vm_page_t m, vm_prot_t prot)
2990{
2991	if ((prot & VM_PROT_WRITE) == 0) {
2992		if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) {
2993			pmap_changebit(m, PG_RW, FALSE);
2994		} else {
2995			pmap_remove_all(m);
2996		}
2997	}
2998}
2999
3000vm_offset_t
3001pmap_phys_address(ppn)
3002	int ppn;
3003{
3004	return (i386_ptob(ppn));
3005}
3006
3007/*
3008 *	pmap_ts_referenced:
3009 *
3010 *	Return the count of reference bits for a page, clearing all of them.
3011 */
3012int
3013pmap_ts_referenced(vm_page_t m)
3014{
3015	register pv_entry_t pv, pvf, pvn;
3016	unsigned *pte;
3017	int s;
3018	int rtval = 0;
3019
3020	if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
3021		return (rtval);
3022
3023	s = splvm();
3024
3025	if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
3026
3027		pvf = pv;
3028
3029		do {
3030			pvn = TAILQ_NEXT(pv, pv_list);
3031
3032			TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
3033
3034			TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
3035
3036			if (!pmap_track_modified(pv->pv_va))
3037				continue;
3038
3039			pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
3040
3041			if (pte && (*pte & PG_A)) {
3042				*pte &= ~PG_A;
3043
3044				pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va);
3045
3046				rtval++;
3047				if (rtval > 4) {
3048					break;
3049				}
3050			}
3051		} while ((pv = pvn) != NULL && pv != pvf);
3052	}
3053	splx(s);
3054
3055	return (rtval);
3056}
3057
3058/*
3059 *	pmap_is_modified:
3060 *
3061 *	Return whether or not the specified physical page was modified
3062 *	in any physical maps.
3063 */
3064boolean_t
3065pmap_is_modified(vm_page_t m)
3066{
3067	return pmap_testbit(m, PG_M);
3068}
3069
3070/*
3071 *	Clear the modify bits on the specified physical page.
3072 */
3073void
3074pmap_clear_modify(vm_page_t m)
3075{
3076	pmap_changebit(m, PG_M, FALSE);
3077}
3078
3079/*
3080 *	pmap_clear_reference:
3081 *
3082 *	Clear the reference bit on the specified physical page.
3083 */
3084void
3085pmap_clear_reference(vm_page_t m)
3086{
3087	pmap_changebit(m, PG_A, FALSE);
3088}
3089
3090/*
3091 * Miscellaneous support routines follow
3092 */
3093
3094static void
3095i386_protection_init()
3096{
3097	register int *kp, prot;
3098
3099	kp = protection_codes;
3100	for (prot = 0; prot < 8; prot++) {
3101		switch (prot) {
3102		case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE:
3103			/*
3104			 * Read access is also 0. There isn't any execute bit,
3105			 * so just make it readable.
3106			 */
3107		case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE:
3108		case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE:
3109		case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE:
3110			*kp++ = 0;
3111			break;
3112		case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE:
3113		case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE:
3114		case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE:
3115		case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE:
3116			*kp++ = PG_RW;
3117			break;
3118		}
3119	}
3120}
3121
3122/*
3123 * Map a set of physical memory pages into the kernel virtual
3124 * address space. Return a pointer to where it is mapped. This
3125 * routine is intended to be used for mapping device memory,
3126 * NOT real memory.
3127 */
3128void *
3129pmap_mapdev(pa, size)
3130	vm_offset_t pa;
3131	vm_size_t size;
3132{
3133	vm_offset_t va, tmpva, offset;
3134	unsigned *pte;
3135
3136	offset = pa & PAGE_MASK;
3137	size = roundup(offset + size, PAGE_SIZE);
3138
3139	va = kmem_alloc_pageable(kernel_map, size);
3140	if (!va)
3141		panic("pmap_mapdev: Couldn't alloc kernel virtual memory");
3142
3143	pa = pa & PG_FRAME;
3144	for (tmpva = va; size > 0;) {
3145		pte = (unsigned *)vtopte(tmpva);
3146		*pte = pa | PG_RW | PG_V | pgeflag;
3147		size -= PAGE_SIZE;
3148		tmpva += PAGE_SIZE;
3149		pa += PAGE_SIZE;
3150	}
3151	invltlb();
3152
3153	return ((void *)(va + offset));
3154}
3155
3156void
3157pmap_unmapdev(va, size)
3158	vm_offset_t va;
3159	vm_size_t size;
3160{
3161	vm_offset_t base, offset;
3162
3163	base = va & PG_FRAME;
3164	offset = va & PAGE_MASK;
3165	size = roundup(offset + size, PAGE_SIZE);
3166	kmem_free(kernel_map, base, size);
3167}
3168
3169/*
3170 * perform the pmap work for mincore
3171 */
3172int
3173pmap_mincore(pmap, addr)
3174	pmap_t pmap;
3175	vm_offset_t addr;
3176{
3177
3178	unsigned *ptep, pte;
3179	vm_page_t m;
3180	int val = 0;
3181
3182	ptep = pmap_pte(pmap, addr);
3183	if (ptep == 0) {
3184		return 0;
3185	}
3186
3187	if ((pte = *ptep) != 0) {
3188		vm_offset_t pa;
3189
3190		val = MINCORE_INCORE;
3191		if ((pte & PG_MANAGED) == 0)
3192			return val;
3193
3194		pa = pte & PG_FRAME;
3195
3196		m = PHYS_TO_VM_PAGE(pa);
3197
3198		/*
3199		 * Modified by us
3200		 */
3201		if (pte & PG_M)
3202			val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER;
3203		/*
3204		 * Modified by someone
3205		 */
3206		else if (m->dirty || pmap_is_modified(m))
3207			val |= MINCORE_MODIFIED_OTHER;
3208		/*
3209		 * Referenced by us
3210		 */
3211		if (pte & PG_A)
3212			val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER;
3213
3214		/*
3215		 * Referenced by someone
3216		 */
3217		else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) {
3218			val |= MINCORE_REFERENCED_OTHER;
3219			vm_page_flag_set(m, PG_REFERENCED);
3220		}
3221	}
3222	return val;
3223}
3224
3225void
3226pmap_activate(struct proc *p)
3227{
3228	pmap_t	pmap;
3229
3230	pmap = vmspace_pmap(p->p_vmspace);
3231#if defined(SMP)
3232	pmap->pm_active |= 1 << PCPU_GET(cpuid);
3233#else
3234	pmap->pm_active |= 1;
3235#endif
3236#if defined(SWTCH_OPTIM_STATS)
3237	tlb_flush_count++;
3238#endif
3239	load_cr3(p->p_addr->u_pcb.pcb_cr3 = vtophys(pmap->pm_pdir));
3240}
3241
3242vm_offset_t
3243pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size)
3244{
3245
3246	if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) {
3247		return addr;
3248	}
3249
3250	addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1);
3251	return addr;
3252}
3253
3254
3255#if defined(PMAP_DEBUG)
3256pmap_pid_dump(int pid)
3257{
3258	pmap_t pmap;
3259	struct proc *p;
3260	int npte = 0;
3261	int index;
3262	ALLPROC_LOCK(AP_SHARED);
3263	LIST_FOREACH(p, &allproc, p_list) {
3264		if (p->p_pid != pid)
3265			continue;
3266
3267		if (p->p_vmspace) {
3268			int i,j;
3269			index = 0;
3270			pmap = vmspace_pmap(p->p_vmspace);
3271			for(i=0;i<1024;i++) {
3272				pd_entry_t *pde;
3273				unsigned *pte;
3274				unsigned base = i << PDRSHIFT;
3275
3276				pde = &pmap->pm_pdir[i];
3277				if (pde && pmap_pde_v(pde)) {
3278					for(j=0;j<1024;j++) {
3279						unsigned va = base + (j << PAGE_SHIFT);
3280						if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) {
3281							if (index) {
3282								index = 0;
3283								printf("\n");
3284							}
3285							ALLPROC_LOCK(AP_RELEASE);
3286							return npte;
3287						}
3288						pte = pmap_pte_quick( pmap, va);
3289						if (pte && pmap_pte_v(pte)) {
3290							vm_offset_t pa;
3291							vm_page_t m;
3292							pa = *(int *)pte;
3293							m = PHYS_TO_VM_PAGE(pa);
3294							printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x",
3295								va, pa, m->hold_count, m->wire_count, m->flags);
3296							npte++;
3297							index++;
3298							if (index >= 2) {
3299								index = 0;
3300								printf("\n");
3301							} else {
3302								printf(" ");
3303							}
3304						}
3305					}
3306				}
3307			}
3308		}
3309	}
3310	ALLPROC_LOCK(AP_RELEASE);
3311	return npte;
3312}
3313#endif
3314
3315#if defined(DEBUG)
3316
3317static void	pads __P((pmap_t pm));
3318void		pmap_pvdump __P((vm_offset_t pa));
3319
3320/* print address space of pmap*/
3321static void
3322pads(pm)
3323	pmap_t pm;
3324{
3325	unsigned va, i, j;
3326	unsigned *ptep;
3327
3328	if (pm == kernel_pmap)
3329		return;
3330	for (i = 0; i < 1024; i++)
3331		if (pm->pm_pdir[i])
3332			for (j = 0; j < 1024; j++) {
3333				va = (i << PDRSHIFT) + (j << PAGE_SHIFT);
3334				if (pm == kernel_pmap && va < KERNBASE)
3335					continue;
3336				if (pm != kernel_pmap && va > UPT_MAX_ADDRESS)
3337					continue;
3338				ptep = pmap_pte_quick(pm, va);
3339				if (pmap_pte_v(ptep))
3340					printf("%x:%x ", va, *(int *) ptep);
3341			};
3342
3343}
3344
3345void
3346pmap_pvdump(pa)
3347	vm_offset_t pa;
3348{
3349	register pv_entry_t pv;
3350	vm_page_t m;
3351
3352	printf("pa %x", pa);
3353	m = PHYS_TO_VM_PAGE(pa);
3354	for (pv = TAILQ_FIRST(&m->md.pv_list);
3355		pv;
3356		pv = TAILQ_NEXT(pv, pv_list)) {
3357#ifdef used_to_be
3358		printf(" -> pmap %p, va %x, flags %x",
3359		    (void *)pv->pv_pmap, pv->pv_va, pv->pv_flags);
3360#endif
3361		printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va);
3362		pads(pv->pv_pmap);
3363	}
3364	printf(" ");
3365}
3366#endif
3367