xref: /dragonfly/sys/platform/pc64/x86_64/pmap.c (revision 52f9f0d9)
1 /*
2  * Copyright (c) 1991 Regents of the University of California.
3  * Copyright (c) 1994 John S. Dyson
4  * Copyright (c) 1994 David Greenman
5  * Copyright (c) 2003 Peter Wemm
6  * Copyright (c) 2005-2008 Alan L. Cox <alc@cs.rice.edu>
7  * Copyright (c) 2008, 2009 The DragonFly Project.
8  * Copyright (c) 2008, 2009 Jordan Gordeev.
9  * Copyright (c) 2011 Matthew Dillon
10  * All rights reserved.
11  *
12  * This code is derived from software contributed to Berkeley by
13  * the Systems Programming Group of the University of Utah Computer
14  * Science Department and William Jolitz of UUNET Technologies Inc.
15  *
16  * Redistribution and use in source and binary forms, with or without
17  * modification, are permitted provided that the following conditions
18  * are met:
19  * 1. Redistributions of source code must retain the above copyright
20  *    notice, this list of conditions and the following disclaimer.
21  * 2. Redistributions in binary form must reproduce the above copyright
22  *    notice, this list of conditions and the following disclaimer in the
23  *    documentation and/or other materials provided with the distribution.
24  * 3. All advertising materials mentioning features or use of this software
25  *    must display the following acknowledgement:
26  *	This product includes software developed by the University of
27  *	California, Berkeley and its contributors.
28  * 4. Neither the name of the University nor the names of its contributors
29  *    may be used to endorse or promote products derived from this software
30  *    without specific prior written permission.
31  *
32  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
33  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
34  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
35  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
36  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
40  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
41  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
42  * SUCH DAMAGE.
43  */
44 /*
45  * Manage physical address maps for x86-64 systems.
46  */
47 
48 #if JG
49 #include "opt_disable_pse.h"
50 #include "opt_pmap.h"
51 #endif
52 #include "opt_msgbuf.h"
53 
54 #include <sys/param.h>
55 #include <sys/systm.h>
56 #include <sys/kernel.h>
57 #include <sys/proc.h>
58 #include <sys/msgbuf.h>
59 #include <sys/vmmeter.h>
60 #include <sys/mman.h>
61 
62 #include <vm/vm.h>
63 #include <vm/vm_param.h>
64 #include <sys/sysctl.h>
65 #include <sys/lock.h>
66 #include <vm/vm_kern.h>
67 #include <vm/vm_page.h>
68 #include <vm/vm_map.h>
69 #include <vm/vm_object.h>
70 #include <vm/vm_extern.h>
71 #include <vm/vm_pageout.h>
72 #include <vm/vm_pager.h>
73 #include <vm/vm_zone.h>
74 
75 #include <sys/user.h>
76 #include <sys/thread2.h>
77 #include <sys/sysref2.h>
78 #include <sys/spinlock2.h>
79 #include <vm/vm_page2.h>
80 
81 #include <machine/cputypes.h>
82 #include <machine/md_var.h>
83 #include <machine/specialreg.h>
84 #include <machine/smp.h>
85 #include <machine_base/apic/apicreg.h>
86 #include <machine/globaldata.h>
87 #include <machine/pmap.h>
88 #include <machine/pmap_inval.h>
89 #include <machine/inttypes.h>
90 
91 #include <ddb/ddb.h>
92 
93 #define PMAP_KEEP_PDIRS
94 #ifndef PMAP_SHPGPERPROC
95 #define PMAP_SHPGPERPROC 2000
96 #endif
97 
98 #if defined(DIAGNOSTIC)
99 #define PMAP_DIAGNOSTIC
100 #endif
101 
102 #define MINPV 2048
103 
104 /*
105  * pmap debugging will report who owns a pv lock when blocking.
106  */
107 #ifdef PMAP_DEBUG
108 
109 #define PMAP_DEBUG_DECL		,const char *func, int lineno
110 #define PMAP_DEBUG_ARGS		, __func__, __LINE__
111 #define PMAP_DEBUG_COPY		, func, lineno
112 
113 #define pv_get(pmap, pindex)		_pv_get(pmap, pindex		\
114 							PMAP_DEBUG_ARGS)
115 #define pv_lock(pv)			_pv_lock(pv			\
116 							PMAP_DEBUG_ARGS)
117 #define pv_hold_try(pv)			_pv_hold_try(pv			\
118 							PMAP_DEBUG_ARGS)
119 #define pv_alloc(pmap, pindex, isnewp)	_pv_alloc(pmap, pindex, isnewp	\
120 							PMAP_DEBUG_ARGS)
121 
122 #else
123 
124 #define PMAP_DEBUG_DECL
125 #define PMAP_DEBUG_ARGS
126 #define PMAP_DEBUG_COPY
127 
128 #define pv_get(pmap, pindex)		_pv_get(pmap, pindex)
129 #define pv_lock(pv)			_pv_lock(pv)
130 #define pv_hold_try(pv)			_pv_hold_try(pv)
131 #define pv_alloc(pmap, pindex, isnewp)	_pv_alloc(pmap, pindex, isnewp)
132 
133 #endif
134 
135 /*
136  * Get PDEs and PTEs for user/kernel address space
137  */
138 #define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT])
139 
140 #define pmap_pde_v(pte)		((*(pd_entry_t *)pte & PG_V) != 0)
141 #define pmap_pte_w(pte)		((*(pt_entry_t *)pte & PG_W) != 0)
142 #define pmap_pte_m(pte)		((*(pt_entry_t *)pte & PG_M) != 0)
143 #define pmap_pte_u(pte)		((*(pt_entry_t *)pte & PG_A) != 0)
144 #define pmap_pte_v(pte)		((*(pt_entry_t *)pte & PG_V) != 0)
145 
146 /*
147  * Given a map and a machine independent protection code,
148  * convert to a vax protection code.
149  */
150 #define pte_prot(m, p)		\
151 	(protection_codes[p & (VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE)])
152 static int protection_codes[8];
153 
154 struct pmap kernel_pmap;
155 static TAILQ_HEAD(,pmap)	pmap_list = TAILQ_HEAD_INITIALIZER(pmap_list);
156 
157 vm_paddr_t avail_start;		/* PA of first available physical page */
158 vm_paddr_t avail_end;		/* PA of last available physical page */
159 vm_offset_t virtual2_start;	/* cutout free area prior to kernel start */
160 vm_offset_t virtual2_end;
161 vm_offset_t virtual_start;	/* VA of first avail page (after kernel bss) */
162 vm_offset_t virtual_end;	/* VA of last avail page (end of kernel AS) */
163 vm_offset_t KvaStart;		/* VA start of KVA space */
164 vm_offset_t KvaEnd;		/* VA end of KVA space (non-inclusive) */
165 vm_offset_t KvaSize;		/* max size of kernel virtual address space */
166 static boolean_t pmap_initialized = FALSE;	/* Has pmap_init completed? */
167 static int pgeflag;		/* PG_G or-in */
168 static int pseflag;		/* PG_PS or-in */
169 
170 static int ndmpdp;
171 static vm_paddr_t dmaplimit;
172 static int nkpt;
173 vm_offset_t kernel_vm_end = VM_MIN_KERNEL_ADDRESS;
174 
175 static uint64_t KPTbase;
176 static uint64_t KPTphys;
177 static uint64_t	KPDphys;	/* phys addr of kernel level 2 */
178 static uint64_t	KPDbase;	/* phys addr of kernel level 2 @ KERNBASE */
179 uint64_t KPDPphys;	/* phys addr of kernel level 3 */
180 uint64_t KPML4phys;	/* phys addr of kernel level 4 */
181 
182 static uint64_t	DMPDphys;	/* phys addr of direct mapped level 2 */
183 static uint64_t	DMPDPphys;	/* phys addr of direct mapped level 3 */
184 
185 /*
186  * Data for the pv entry allocation mechanism
187  */
188 static vm_zone_t pvzone;
189 static struct vm_zone pvzone_store;
190 static struct vm_object pvzone_obj;
191 static int pv_entry_max=0, pv_entry_high_water=0;
192 static int pmap_pagedaemon_waken = 0;
193 static struct pv_entry *pvinit;
194 
195 /*
196  * All those kernel PT submaps that BSD is so fond of
197  */
198 pt_entry_t *CMAP1 = NULL, *ptmmap;
199 caddr_t CADDR1 = 0, ptvmmap = 0;
200 static pt_entry_t *msgbufmap;
201 struct msgbuf *msgbufp=NULL;
202 
203 /*
204  * Crashdump maps.
205  */
206 static pt_entry_t *pt_crashdumpmap;
207 static caddr_t crashdumpmap;
208 
209 static int pmap_yield_count = 64;
210 SYSCTL_INT(_machdep, OID_AUTO, pmap_yield_count, CTLFLAG_RW,
211     &pmap_yield_count, 0, "Yield during init_pt/release");
212 
213 #define DISABLE_PSE
214 
215 static void pv_hold(pv_entry_t pv);
216 static int _pv_hold_try(pv_entry_t pv
217 				PMAP_DEBUG_DECL);
218 static void pv_drop(pv_entry_t pv);
219 static void _pv_lock(pv_entry_t pv
220 				PMAP_DEBUG_DECL);
221 static void pv_unlock(pv_entry_t pv);
222 static pv_entry_t _pv_alloc(pmap_t pmap, vm_pindex_t pindex, int *isnew
223 				PMAP_DEBUG_DECL);
224 static pv_entry_t _pv_get(pmap_t pmap, vm_pindex_t pindex
225 				PMAP_DEBUG_DECL);
226 static pv_entry_t pv_get_try(pmap_t pmap, vm_pindex_t pindex, int *errorp);
227 static pv_entry_t pv_find(pmap_t pmap, vm_pindex_t pindex);
228 static void pv_put(pv_entry_t pv);
229 static void pv_free(pv_entry_t pv);
230 static void *pv_pte_lookup(pv_entry_t pv, vm_pindex_t pindex);
231 static pv_entry_t pmap_allocpte(pmap_t pmap, vm_pindex_t ptepindex,
232 		      pv_entry_t *pvpp);
233 static void pmap_remove_pv_pte(pv_entry_t pv, pv_entry_t pvp,
234 		      struct pmap_inval_info *info);
235 static vm_page_t pmap_remove_pv_page(pv_entry_t pv);
236 
237 static void pmap_remove_callback(pmap_t pmap, struct pmap_inval_info *info,
238 		      pv_entry_t pte_pv, pv_entry_t pt_pv, vm_offset_t va,
239 		      pt_entry_t *ptep, void *arg __unused);
240 static void pmap_protect_callback(pmap_t pmap, struct pmap_inval_info *info,
241 		      pv_entry_t pte_pv, pv_entry_t pt_pv, vm_offset_t va,
242 		      pt_entry_t *ptep, void *arg __unused);
243 
244 static void i386_protection_init (void);
245 static void create_pagetables(vm_paddr_t *firstaddr);
246 static void pmap_remove_all (vm_page_t m);
247 static boolean_t pmap_testbit (vm_page_t m, int bit);
248 
249 static pt_entry_t * pmap_pte_quick (pmap_t pmap, vm_offset_t va);
250 static vm_offset_t pmap_kmem_choose(vm_offset_t addr);
251 
252 static unsigned pdir4mb;
253 
254 static int
255 pv_entry_compare(pv_entry_t pv1, pv_entry_t pv2)
256 {
257 	if (pv1->pv_pindex < pv2->pv_pindex)
258 		return(-1);
259 	if (pv1->pv_pindex > pv2->pv_pindex)
260 		return(1);
261 	return(0);
262 }
263 
264 RB_GENERATE2(pv_entry_rb_tree, pv_entry, pv_entry,
265              pv_entry_compare, vm_pindex_t, pv_pindex);
266 
267 /*
268  * Move the kernel virtual free pointer to the next
269  * 2MB.  This is used to help improve performance
270  * by using a large (2MB) page for much of the kernel
271  * (.text, .data, .bss)
272  */
273 static
274 vm_offset_t
275 pmap_kmem_choose(vm_offset_t addr)
276 {
277 	vm_offset_t newaddr = addr;
278 
279 	newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1);
280 	return newaddr;
281 }
282 
283 /*
284  * pmap_pte_quick:
285  *
286  *	Super fast pmap_pte routine best used when scanning the pv lists.
287  *	This eliminates many course-grained invltlb calls.  Note that many of
288  *	the pv list scans are across different pmaps and it is very wasteful
289  *	to do an entire invltlb when checking a single mapping.
290  */
291 static __inline pt_entry_t *pmap_pte(pmap_t pmap, vm_offset_t va);
292 
293 static
294 pt_entry_t *
295 pmap_pte_quick(pmap_t pmap, vm_offset_t va)
296 {
297 	return pmap_pte(pmap, va);
298 }
299 
300 /*
301  * Returns the pindex of a page table entry (representing a terminal page).
302  * There are NUPTE_TOTAL page table entries possible (a huge number)
303  *
304  * x86-64 has a 48-bit address space, where bit 47 is sign-extended out.
305  * We want to properly translate negative KVAs.
306  */
307 static __inline
308 vm_pindex_t
309 pmap_pte_pindex(vm_offset_t va)
310 {
311 	return ((va >> PAGE_SHIFT) & (NUPTE_TOTAL - 1));
312 }
313 
314 /*
315  * Returns the pindex of a page table.
316  */
317 static __inline
318 vm_pindex_t
319 pmap_pt_pindex(vm_offset_t va)
320 {
321 	return (NUPTE_TOTAL + ((va >> PDRSHIFT) & (NUPT_TOTAL - 1)));
322 }
323 
324 /*
325  * Returns the pindex of a page directory.
326  */
327 static __inline
328 vm_pindex_t
329 pmap_pd_pindex(vm_offset_t va)
330 {
331 	return (NUPTE_TOTAL + NUPT_TOTAL +
332 		((va >> PDPSHIFT) & (NUPD_TOTAL - 1)));
333 }
334 
335 static __inline
336 vm_pindex_t
337 pmap_pdp_pindex(vm_offset_t va)
338 {
339 	return (NUPTE_TOTAL + NUPT_TOTAL + NUPD_TOTAL +
340 		((va >> PML4SHIFT) & (NUPDP_TOTAL - 1)));
341 }
342 
343 static __inline
344 vm_pindex_t
345 pmap_pml4_pindex(void)
346 {
347 	return (NUPTE_TOTAL + NUPT_TOTAL + NUPD_TOTAL + NUPDP_TOTAL);
348 }
349 
350 /*
351  * Return various clipped indexes for a given VA
352  *
353  * Returns the index of a pte in a page table, representing a terminal
354  * page.
355  */
356 static __inline
357 vm_pindex_t
358 pmap_pte_index(vm_offset_t va)
359 {
360 	return ((va >> PAGE_SHIFT) & ((1ul << NPTEPGSHIFT) - 1));
361 }
362 
363 /*
364  * Returns the index of a pt in a page directory, representing a page
365  * table.
366  */
367 static __inline
368 vm_pindex_t
369 pmap_pt_index(vm_offset_t va)
370 {
371 	return ((va >> PDRSHIFT) & ((1ul << NPDEPGSHIFT) - 1));
372 }
373 
374 /*
375  * Returns the index of a pd in a page directory page, representing a page
376  * directory.
377  */
378 static __inline
379 vm_pindex_t
380 pmap_pd_index(vm_offset_t va)
381 {
382 	return ((va >> PDPSHIFT) & ((1ul << NPDPEPGSHIFT) - 1));
383 }
384 
385 /*
386  * Returns the index of a pdp in the pml4 table, representing a page
387  * directory page.
388  */
389 static __inline
390 vm_pindex_t
391 pmap_pdp_index(vm_offset_t va)
392 {
393 	return ((va >> PML4SHIFT) & ((1ul << NPML4EPGSHIFT) - 1));
394 }
395 
396 /*
397  * Generic procedure to index a pte from a pt, pd, or pdp.
398  */
399 static
400 void *
401 pv_pte_lookup(pv_entry_t pv, vm_pindex_t pindex)
402 {
403 	pt_entry_t *pte;
404 
405 	pte = (pt_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(pv->pv_m));
406 	return(&pte[pindex]);
407 }
408 
409 /*
410  * Return pointer to PDP slot in the PML4
411  */
412 static __inline
413 pml4_entry_t *
414 pmap_pdp(pmap_t pmap, vm_offset_t va)
415 {
416 	return (&pmap->pm_pml4[pmap_pdp_index(va)]);
417 }
418 
419 /*
420  * Return pointer to PD slot in the PDP given a pointer to the PDP
421  */
422 static __inline
423 pdp_entry_t *
424 pmap_pdp_to_pd(pml4_entry_t *pdp, vm_offset_t va)
425 {
426 	pdp_entry_t *pd;
427 
428 	pd = (pdp_entry_t *)PHYS_TO_DMAP(*pdp & PG_FRAME);
429 	return (&pd[pmap_pd_index(va)]);
430 }
431 
432 /*
433  * Return pointer to PD slot in the PDP
434  **/
435 static __inline
436 pdp_entry_t *
437 pmap_pd(pmap_t pmap, vm_offset_t va)
438 {
439 	pml4_entry_t *pdp;
440 
441 	pdp = pmap_pdp(pmap, va);
442 	if ((*pdp & PG_V) == 0)
443 		return NULL;
444 	return (pmap_pdp_to_pd(pdp, va));
445 }
446 
447 /*
448  * Return pointer to PT slot in the PD given a pointer to the PD
449  */
450 static __inline
451 pd_entry_t *
452 pmap_pd_to_pt(pdp_entry_t *pd, vm_offset_t va)
453 {
454 	pd_entry_t *pt;
455 
456 	pt = (pd_entry_t *)PHYS_TO_DMAP(*pd & PG_FRAME);
457 	return (&pt[pmap_pt_index(va)]);
458 }
459 
460 /*
461  * Return pointer to PT slot in the PD
462  */
463 static __inline
464 pd_entry_t *
465 pmap_pt(pmap_t pmap, vm_offset_t va)
466 {
467 	pdp_entry_t *pd;
468 
469 	pd = pmap_pd(pmap, va);
470 	if (pd == NULL || (*pd & PG_V) == 0)
471 		 return NULL;
472 	return (pmap_pd_to_pt(pd, va));
473 }
474 
475 /*
476  * Return pointer to PTE slot in the PT given a pointer to the PT
477  */
478 static __inline
479 pt_entry_t *
480 pmap_pt_to_pte(pd_entry_t *pt, vm_offset_t va)
481 {
482 	pt_entry_t *pte;
483 
484 	pte = (pt_entry_t *)PHYS_TO_DMAP(*pt & PG_FRAME);
485 	return (&pte[pmap_pte_index(va)]);
486 }
487 
488 /*
489  * Return pointer to PTE slot in the PT
490  */
491 static __inline
492 pt_entry_t *
493 pmap_pte(pmap_t pmap, vm_offset_t va)
494 {
495 	pd_entry_t *pt;
496 
497 	pt = pmap_pt(pmap, va);
498 	if (pt == NULL || (*pt & PG_V) == 0)
499 		 return NULL;
500 	if ((*pt & PG_PS) != 0)
501 		return ((pt_entry_t *)pt);
502 	return (pmap_pt_to_pte(pt, va));
503 }
504 
505 /*
506  * Of all the layers (PTE, PT, PD, PDP, PML4) the best one to cache is
507  * the PT layer.  This will speed up core pmap operations considerably.
508  */
509 static __inline
510 void
511 pv_cache(pv_entry_t pv, vm_pindex_t pindex)
512 {
513 	if (pindex >= pmap_pt_pindex(0) && pindex <= pmap_pd_pindex(0))
514 		pv->pv_pmap->pm_pvhint = pv;
515 }
516 
517 
518 /*
519  * KVM - return address of PT slot in PD
520  */
521 static __inline
522 pd_entry_t *
523 vtopt(vm_offset_t va)
524 {
525 	uint64_t mask = ((1ul << (NPDEPGSHIFT + NPDPEPGSHIFT +
526 				  NPML4EPGSHIFT)) - 1);
527 
528 	return (PDmap + ((va >> PDRSHIFT) & mask));
529 }
530 
531 /*
532  * KVM - return address of PTE slot in PT
533  */
534 static __inline
535 pt_entry_t *
536 vtopte(vm_offset_t va)
537 {
538 	uint64_t mask = ((1ul << (NPTEPGSHIFT + NPDEPGSHIFT +
539 				  NPDPEPGSHIFT + NPML4EPGSHIFT)) - 1);
540 
541 	return (PTmap + ((va >> PAGE_SHIFT) & mask));
542 }
543 
544 static uint64_t
545 allocpages(vm_paddr_t *firstaddr, long n)
546 {
547 	uint64_t ret;
548 
549 	ret = *firstaddr;
550 	bzero((void *)ret, n * PAGE_SIZE);
551 	*firstaddr += n * PAGE_SIZE;
552 	return (ret);
553 }
554 
555 static
556 void
557 create_pagetables(vm_paddr_t *firstaddr)
558 {
559 	long i;		/* must be 64 bits */
560 	long nkpt_base;
561 	long nkpt_phys;
562 	int j;
563 
564 	/*
565 	 * We are running (mostly) V=P at this point
566 	 *
567 	 * Calculate NKPT - number of kernel page tables.  We have to
568 	 * accomodoate prealloction of the vm_page_array, dump bitmap,
569 	 * MSGBUF_SIZE, and other stuff.  Be generous.
570 	 *
571 	 * Maxmem is in pages.
572 	 *
573 	 * ndmpdp is the number of 1GB pages we wish to map.
574 	 */
575 	ndmpdp = (ptoa(Maxmem) + NBPDP - 1) >> PDPSHIFT;
576 	if (ndmpdp < 4)		/* Minimum 4GB of dirmap */
577 		ndmpdp = 4;
578 	KKASSERT(ndmpdp <= NKPDPE * NPDEPG);
579 
580 	/*
581 	 * Starting at the beginning of kvm (not KERNBASE).
582 	 */
583 	nkpt_phys = (Maxmem * sizeof(struct vm_page) + NBPDR - 1) / NBPDR;
584 	nkpt_phys += (Maxmem * sizeof(struct pv_entry) + NBPDR - 1) / NBPDR;
585 	nkpt_phys += ((nkpt + nkpt + 1 + NKPML4E + NKPDPE + NDMPML4E +
586 		       ndmpdp) + 511) / 512;
587 	nkpt_phys += 128;
588 
589 	/*
590 	 * Starting at KERNBASE - map 2G worth of page table pages.
591 	 * KERNBASE is offset -2G from the end of kvm.
592 	 */
593 	nkpt_base = (NPDPEPG - KPDPI) * NPTEPG;	/* typically 2 x 512 */
594 
595 	/*
596 	 * Allocate pages
597 	 */
598 	KPTbase = allocpages(firstaddr, nkpt_base);
599 	KPTphys = allocpages(firstaddr, nkpt_phys);
600 	KPML4phys = allocpages(firstaddr, 1);
601 	KPDPphys = allocpages(firstaddr, NKPML4E);
602 	KPDphys = allocpages(firstaddr, NKPDPE);
603 
604 	/*
605 	 * Calculate the page directory base for KERNBASE,
606 	 * that is where we start populating the page table pages.
607 	 * Basically this is the end - 2.
608 	 */
609 	KPDbase = KPDphys + ((NKPDPE - (NPDPEPG - KPDPI)) << PAGE_SHIFT);
610 
611 	DMPDPphys = allocpages(firstaddr, NDMPML4E);
612 	if ((amd_feature & AMDID_PAGE1GB) == 0)
613 		DMPDphys = allocpages(firstaddr, ndmpdp);
614 	dmaplimit = (vm_paddr_t)ndmpdp << PDPSHIFT;
615 
616 	/*
617 	 * Fill in the underlying page table pages for the area around
618 	 * KERNBASE.  This remaps low physical memory to KERNBASE.
619 	 *
620 	 * Read-only from zero to physfree
621 	 * XXX not fully used, underneath 2M pages
622 	 */
623 	for (i = 0; (i << PAGE_SHIFT) < *firstaddr; i++) {
624 		((pt_entry_t *)KPTbase)[i] = i << PAGE_SHIFT;
625 		((pt_entry_t *)KPTbase)[i] |= PG_RW | PG_V | PG_G;
626 	}
627 
628 	/*
629 	 * Now map the initial kernel page tables.  One block of page
630 	 * tables is placed at the beginning of kernel virtual memory,
631 	 * and another block is placed at KERNBASE to map the kernel binary,
632 	 * data, bss, and initial pre-allocations.
633 	 */
634 	for (i = 0; i < nkpt_base; i++) {
635 		((pd_entry_t *)KPDbase)[i] = KPTbase + (i << PAGE_SHIFT);
636 		((pd_entry_t *)KPDbase)[i] |= PG_RW | PG_V;
637 	}
638 	for (i = 0; i < nkpt_phys; i++) {
639 		((pd_entry_t *)KPDphys)[i] = KPTphys + (i << PAGE_SHIFT);
640 		((pd_entry_t *)KPDphys)[i] |= PG_RW | PG_V;
641 	}
642 
643 	/*
644 	 * Map from zero to end of allocations using 2M pages as an
645 	 * optimization.  This will bypass some of the KPTBase pages
646 	 * above in the KERNBASE area.
647 	 */
648 	for (i = 0; (i << PDRSHIFT) < *firstaddr; i++) {
649 		((pd_entry_t *)KPDbase)[i] = i << PDRSHIFT;
650 		((pd_entry_t *)KPDbase)[i] |= PG_RW | PG_V | PG_PS | PG_G;
651 	}
652 
653 	/*
654 	 * And connect up the PD to the PDP.  The kernel pmap is expected
655 	 * to pre-populate all of its PDs.  See NKPDPE in vmparam.h.
656 	 */
657 	for (i = 0; i < NKPDPE; i++) {
658 		((pdp_entry_t *)KPDPphys)[NPDPEPG - NKPDPE + i] =
659 				KPDphys + (i << PAGE_SHIFT);
660 		((pdp_entry_t *)KPDPphys)[NPDPEPG - NKPDPE + i] |=
661 				PG_RW | PG_V | PG_U;
662 	}
663 
664 	/*
665 	 * Now set up the direct map space using either 2MB or 1GB pages
666 	 * Preset PG_M and PG_A because demotion expects it.
667 	 *
668 	 * When filling in entries in the PD pages make sure any excess
669 	 * entries are set to zero as we allocated enough PD pages
670 	 */
671 	if ((amd_feature & AMDID_PAGE1GB) == 0) {
672 		for (i = 0; i < NPDEPG * ndmpdp; i++) {
673 			((pd_entry_t *)DMPDphys)[i] = i << PDRSHIFT;
674 			((pd_entry_t *)DMPDphys)[i] |= PG_RW | PG_V | PG_PS |
675 						       PG_G | PG_M | PG_A;
676 		}
677 
678 		/*
679 		 * And the direct map space's PDP
680 		 */
681 		for (i = 0; i < ndmpdp; i++) {
682 			((pdp_entry_t *)DMPDPphys)[i] = DMPDphys +
683 							(i << PAGE_SHIFT);
684 			((pdp_entry_t *)DMPDPphys)[i] |= PG_RW | PG_V | PG_U;
685 		}
686 	} else {
687 		for (i = 0; i < ndmpdp; i++) {
688 			((pdp_entry_t *)DMPDPphys)[i] =
689 						(vm_paddr_t)i << PDPSHIFT;
690 			((pdp_entry_t *)DMPDPphys)[i] |= PG_RW | PG_V | PG_PS |
691 							 PG_G | PG_M | PG_A;
692 		}
693 	}
694 
695 	/* And recursively map PML4 to itself in order to get PTmap */
696 	((pdp_entry_t *)KPML4phys)[PML4PML4I] = KPML4phys;
697 	((pdp_entry_t *)KPML4phys)[PML4PML4I] |= PG_RW | PG_V | PG_U;
698 
699 	/*
700 	 * Connect the Direct Map slots up to the PML4
701 	 */
702 	for (j = 0; j < NDMPML4E; ++j) {
703 		((pdp_entry_t *)KPML4phys)[DMPML4I + j] =
704 			(DMPDPphys + ((vm_paddr_t)j << PML4SHIFT)) |
705 			PG_RW | PG_V | PG_U;
706 	}
707 
708 	/*
709 	 * Connect the KVA slot up to the PML4
710 	 */
711 	((pdp_entry_t *)KPML4phys)[KPML4I] = KPDPphys;
712 	((pdp_entry_t *)KPML4phys)[KPML4I] |= PG_RW | PG_V | PG_U;
713 }
714 
715 /*
716  *	Bootstrap the system enough to run with virtual memory.
717  *
718  *	On the i386 this is called after mapping has already been enabled
719  *	and just syncs the pmap module with what has already been done.
720  *	[We can't call it easily with mapping off since the kernel is not
721  *	mapped with PA == VA, hence we would have to relocate every address
722  *	from the linked base (virtual) address "KERNBASE" to the actual
723  *	(physical) address starting relative to 0]
724  */
725 void
726 pmap_bootstrap(vm_paddr_t *firstaddr)
727 {
728 	vm_offset_t va;
729 	pt_entry_t *pte;
730 	struct mdglobaldata *gd;
731 	int pg;
732 
733 	KvaStart = VM_MIN_KERNEL_ADDRESS;
734 	KvaEnd = VM_MAX_KERNEL_ADDRESS;
735 	KvaSize = KvaEnd - KvaStart;
736 
737 	avail_start = *firstaddr;
738 
739 	/*
740 	 * Create an initial set of page tables to run the kernel in.
741 	 */
742 	create_pagetables(firstaddr);
743 
744 	virtual2_start = KvaStart;
745 	virtual2_end = PTOV_OFFSET;
746 
747 	virtual_start = (vm_offset_t) PTOV_OFFSET + *firstaddr;
748 	virtual_start = pmap_kmem_choose(virtual_start);
749 
750 	virtual_end = VM_MAX_KERNEL_ADDRESS;
751 
752 	/* XXX do %cr0 as well */
753 	load_cr4(rcr4() | CR4_PGE | CR4_PSE);
754 	load_cr3(KPML4phys);
755 
756 	/*
757 	 * Initialize protection array.
758 	 */
759 	i386_protection_init();
760 
761 	/*
762 	 * The kernel's pmap is statically allocated so we don't have to use
763 	 * pmap_create, which is unlikely to work correctly at this part of
764 	 * the boot sequence (XXX and which no longer exists).
765 	 */
766 	kernel_pmap.pm_pml4 = (pdp_entry_t *) (PTOV_OFFSET + KPML4phys);
767 	kernel_pmap.pm_count = 1;
768 	kernel_pmap.pm_active = (cpumask_t)-1 & ~CPUMASK_LOCK;
769 	RB_INIT(&kernel_pmap.pm_pvroot);
770 	spin_init(&kernel_pmap.pm_spin);
771 	lwkt_token_init(&kernel_pmap.pm_token, "kpmap_tok");
772 
773 	/*
774 	 * Reserve some special page table entries/VA space for temporary
775 	 * mapping of pages.
776 	 */
777 #define	SYSMAP(c, p, v, n)	\
778 	v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n);
779 
780 	va = virtual_start;
781 	pte = vtopte(va);
782 
783 	/*
784 	 * CMAP1/CMAP2 are used for zeroing and copying pages.
785 	 */
786 	SYSMAP(caddr_t, CMAP1, CADDR1, 1)
787 
788 	/*
789 	 * Crashdump maps.
790 	 */
791 	SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS);
792 
793 	/*
794 	 * ptvmmap is used for reading arbitrary physical pages via
795 	 * /dev/mem.
796 	 */
797 	SYSMAP(caddr_t, ptmmap, ptvmmap, 1)
798 
799 	/*
800 	 * msgbufp is used to map the system message buffer.
801 	 * XXX msgbufmap is not used.
802 	 */
803 	SYSMAP(struct msgbuf *, msgbufmap, msgbufp,
804 	       atop(round_page(MSGBUF_SIZE)))
805 
806 	virtual_start = va;
807 
808 	*CMAP1 = 0;
809 
810 	/*
811 	 * PG_G is terribly broken on SMP because we IPI invltlb's in some
812 	 * cases rather then invl1pg.  Actually, I don't even know why it
813 	 * works under UP because self-referential page table mappings
814 	 */
815 #ifdef SMP
816 	pgeflag = 0;
817 #else
818 	if (cpu_feature & CPUID_PGE)
819 		pgeflag = PG_G;
820 #endif
821 
822 /*
823  * Initialize the 4MB page size flag
824  */
825 	pseflag = 0;
826 /*
827  * The 4MB page version of the initial
828  * kernel page mapping.
829  */
830 	pdir4mb = 0;
831 
832 #if !defined(DISABLE_PSE)
833 	if (cpu_feature & CPUID_PSE) {
834 		pt_entry_t ptditmp;
835 		/*
836 		 * Note that we have enabled PSE mode
837 		 */
838 		pseflag = PG_PS;
839 		ptditmp = *(PTmap + x86_64_btop(KERNBASE));
840 		ptditmp &= ~(NBPDR - 1);
841 		ptditmp |= PG_V | PG_RW | PG_PS | PG_U | pgeflag;
842 		pdir4mb = ptditmp;
843 
844 #ifndef SMP
845 		/*
846 		 * Enable the PSE mode.  If we are SMP we can't do this
847 		 * now because the APs will not be able to use it when
848 		 * they boot up.
849 		 */
850 		load_cr4(rcr4() | CR4_PSE);
851 
852 		/*
853 		 * We can do the mapping here for the single processor
854 		 * case.  We simply ignore the old page table page from
855 		 * now on.
856 		 */
857 		/*
858 		 * For SMP, we still need 4K pages to bootstrap APs,
859 		 * PSE will be enabled as soon as all APs are up.
860 		 */
861 		PTD[KPTDI] = (pd_entry_t)ptditmp;
862 		cpu_invltlb();
863 #endif
864 	}
865 #endif
866 
867 	/*
868 	 * We need to finish setting up the globaldata page for the BSP.
869 	 * locore has already populated the page table for the mdglobaldata
870 	 * portion.
871 	 */
872 	pg = MDGLOBALDATA_BASEALLOC_PAGES;
873 	gd = &CPU_prvspace[0].mdglobaldata;
874 
875 	cpu_invltlb();
876 }
877 
878 #ifdef SMP
879 /*
880  * Set 4mb pdir for mp startup
881  */
882 void
883 pmap_set_opt(void)
884 {
885 	if (pseflag && (cpu_feature & CPUID_PSE)) {
886 		load_cr4(rcr4() | CR4_PSE);
887 		if (pdir4mb && mycpu->gd_cpuid == 0) {	/* only on BSP */
888 			cpu_invltlb();
889 		}
890 	}
891 }
892 #endif
893 
894 /*
895  *	Initialize the pmap module.
896  *	Called by vm_init, to initialize any structures that the pmap
897  *	system needs to map virtual memory.
898  *	pmap_init has been enhanced to support in a fairly consistant
899  *	way, discontiguous physical memory.
900  */
901 void
902 pmap_init(void)
903 {
904 	int i;
905 	int initial_pvs;
906 
907 	/*
908 	 * Allocate memory for random pmap data structures.  Includes the
909 	 * pv_head_table.
910 	 */
911 
912 	for (i = 0; i < vm_page_array_size; i++) {
913 		vm_page_t m;
914 
915 		m = &vm_page_array[i];
916 		TAILQ_INIT(&m->md.pv_list);
917 	}
918 
919 	/*
920 	 * init the pv free list
921 	 */
922 	initial_pvs = vm_page_array_size;
923 	if (initial_pvs < MINPV)
924 		initial_pvs = MINPV;
925 	pvzone = &pvzone_store;
926 	pvinit = (void *)kmem_alloc(&kernel_map,
927 				    initial_pvs * sizeof (struct pv_entry));
928 	zbootinit(pvzone, "PV ENTRY", sizeof (struct pv_entry),
929 		  pvinit, initial_pvs);
930 
931 	/*
932 	 * Now it is safe to enable pv_table recording.
933 	 */
934 	pmap_initialized = TRUE;
935 }
936 
937 /*
938  * Initialize the address space (zone) for the pv_entries.  Set a
939  * high water mark so that the system can recover from excessive
940  * numbers of pv entries.
941  */
942 void
943 pmap_init2(void)
944 {
945 	int shpgperproc = PMAP_SHPGPERPROC;
946 	int entry_max;
947 
948 	TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc);
949 	pv_entry_max = shpgperproc * maxproc + vm_page_array_size;
950 	TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max);
951 	pv_entry_high_water = 9 * (pv_entry_max / 10);
952 
953 	/*
954 	 * Subtract out pages already installed in the zone (hack)
955 	 */
956 	entry_max = pv_entry_max - vm_page_array_size;
957 	if (entry_max <= 0)
958 		entry_max = 1;
959 
960 	zinitna(pvzone, &pvzone_obj, NULL, 0, entry_max, ZONE_INTERRUPT, 1);
961 }
962 
963 
964 /***************************************************
965  * Low level helper routines.....
966  ***************************************************/
967 
968 /*
969  * this routine defines the region(s) of memory that should
970  * not be tested for the modified bit.
971  */
972 static __inline
973 int
974 pmap_track_modified(vm_pindex_t pindex)
975 {
976 	vm_offset_t va = (vm_offset_t)pindex << PAGE_SHIFT;
977 	if ((va < clean_sva) || (va >= clean_eva))
978 		return 1;
979 	else
980 		return 0;
981 }
982 
983 /*
984  * Extract the physical page address associated with the map/VA pair.
985  * The page must be wired for this to work reliably.
986  *
987  * XXX for the moment we're using pv_find() instead of pv_get(), as
988  *     callers might be expecting non-blocking operation.
989  */
990 vm_paddr_t
991 pmap_extract(pmap_t pmap, vm_offset_t va)
992 {
993 	vm_paddr_t rtval;
994 	pv_entry_t pt_pv;
995 	pt_entry_t *ptep;
996 
997 	rtval = 0;
998 	if (va >= VM_MAX_USER_ADDRESS) {
999 		/*
1000 		 * Kernel page directories might be direct-mapped and
1001 		 * there is typically no PV tracking of pte's
1002 		 */
1003 		pd_entry_t *pt;
1004 
1005 		pt = pmap_pt(pmap, va);
1006 		if (pt && (*pt & PG_V)) {
1007 			if (*pt & PG_PS) {
1008 				rtval = *pt & PG_PS_FRAME;
1009 				rtval |= va & PDRMASK;
1010 			} else {
1011 				ptep = pmap_pt_to_pte(pt, va);
1012 				if (*pt & PG_V) {
1013 					rtval = *ptep & PG_FRAME;
1014 					rtval |= va & PAGE_MASK;
1015 				}
1016 			}
1017 		}
1018 	} else {
1019 		/*
1020 		 * User pages currently do not direct-map the page directory
1021 		 * and some pages might not used managed PVs.  But all PT's
1022 		 * will have a PV.
1023 		 */
1024 		pt_pv = pv_find(pmap, pmap_pt_pindex(va));
1025 		if (pt_pv) {
1026 			ptep = pv_pte_lookup(pt_pv, pmap_pte_index(va));
1027 			if (*ptep & PG_V) {
1028 				rtval = *ptep & PG_FRAME;
1029 				rtval |= va & PAGE_MASK;
1030 			}
1031 			pv_drop(pt_pv);
1032 		}
1033 	}
1034 	return rtval;
1035 }
1036 
1037 /*
1038  * Extract the physical page address associated kernel virtual address.
1039  */
1040 vm_paddr_t
1041 pmap_kextract(vm_offset_t va)
1042 {
1043 	pd_entry_t pt;		/* pt entry in pd */
1044 	vm_paddr_t pa;
1045 
1046 	if (va >= DMAP_MIN_ADDRESS && va < DMAP_MAX_ADDRESS) {
1047 		pa = DMAP_TO_PHYS(va);
1048 	} else {
1049 		pt = *vtopt(va);
1050 		if (pt & PG_PS) {
1051 			pa = (pt & PG_PS_FRAME) | (va & PDRMASK);
1052 		} else {
1053 			/*
1054 			 * Beware of a concurrent promotion that changes the
1055 			 * PDE at this point!  For example, vtopte() must not
1056 			 * be used to access the PTE because it would use the
1057 			 * new PDE.  It is, however, safe to use the old PDE
1058 			 * because the page table page is preserved by the
1059 			 * promotion.
1060 			 */
1061 			pa = *pmap_pt_to_pte(&pt, va);
1062 			pa = (pa & PG_FRAME) | (va & PAGE_MASK);
1063 		}
1064 	}
1065 	return pa;
1066 }
1067 
1068 /***************************************************
1069  * Low level mapping routines.....
1070  ***************************************************/
1071 
1072 /*
1073  * Routine: pmap_kenter
1074  * Function:
1075  *  	Add a wired page to the KVA
1076  *  	NOTE! note that in order for the mapping to take effect -- you
1077  *  	should do an invltlb after doing the pmap_kenter().
1078  */
1079 void
1080 pmap_kenter(vm_offset_t va, vm_paddr_t pa)
1081 {
1082 	pt_entry_t *pte;
1083 	pt_entry_t npte;
1084 	pmap_inval_info info;
1085 
1086 	pmap_inval_init(&info);				/* XXX remove */
1087 	npte = pa | PG_RW | PG_V | pgeflag;
1088 	pte = vtopte(va);
1089 	pmap_inval_interlock(&info, &kernel_pmap, va);	/* XXX remove */
1090 	*pte = npte;
1091 	pmap_inval_deinterlock(&info, &kernel_pmap);	/* XXX remove */
1092 	pmap_inval_done(&info);				/* XXX remove */
1093 }
1094 
1095 /*
1096  * Routine: pmap_kenter_quick
1097  * Function:
1098  *  	Similar to pmap_kenter(), except we only invalidate the
1099  *  	mapping on the current CPU.
1100  */
1101 void
1102 pmap_kenter_quick(vm_offset_t va, vm_paddr_t pa)
1103 {
1104 	pt_entry_t *pte;
1105 	pt_entry_t npte;
1106 
1107 	npte = pa | PG_RW | PG_V | pgeflag;
1108 	pte = vtopte(va);
1109 	*pte = npte;
1110 	cpu_invlpg((void *)va);
1111 }
1112 
1113 void
1114 pmap_kenter_sync(vm_offset_t va)
1115 {
1116 	pmap_inval_info info;
1117 
1118 	pmap_inval_init(&info);
1119 	pmap_inval_interlock(&info, &kernel_pmap, va);
1120 	pmap_inval_deinterlock(&info, &kernel_pmap);
1121 	pmap_inval_done(&info);
1122 }
1123 
1124 void
1125 pmap_kenter_sync_quick(vm_offset_t va)
1126 {
1127 	cpu_invlpg((void *)va);
1128 }
1129 
1130 /*
1131  * remove a page from the kernel pagetables
1132  */
1133 void
1134 pmap_kremove(vm_offset_t va)
1135 {
1136 	pt_entry_t *pte;
1137 	pmap_inval_info info;
1138 
1139 	pmap_inval_init(&info);
1140 	pte = vtopte(va);
1141 	pmap_inval_interlock(&info, &kernel_pmap, va);
1142 	(void)pte_load_clear(pte);
1143 	pmap_inval_deinterlock(&info, &kernel_pmap);
1144 	pmap_inval_done(&info);
1145 }
1146 
1147 void
1148 pmap_kremove_quick(vm_offset_t va)
1149 {
1150 	pt_entry_t *pte;
1151 	pte = vtopte(va);
1152 	(void)pte_load_clear(pte);
1153 	cpu_invlpg((void *)va);
1154 }
1155 
1156 /*
1157  * XXX these need to be recoded.  They are not used in any critical path.
1158  */
1159 void
1160 pmap_kmodify_rw(vm_offset_t va)
1161 {
1162 	atomic_set_long(vtopte(va), PG_RW);
1163 	cpu_invlpg((void *)va);
1164 }
1165 
1166 void
1167 pmap_kmodify_nc(vm_offset_t va)
1168 {
1169 	atomic_set_long(vtopte(va), PG_N);
1170 	cpu_invlpg((void *)va);
1171 }
1172 
1173 /*
1174  * Used to map a range of physical addresses into kernel virtual
1175  * address space during the low level boot, typically to map the
1176  * dump bitmap, message buffer, and vm_page_array.
1177  *
1178  * These mappings are typically made at some pointer after the end of the
1179  * kernel text+data.
1180  *
1181  * We could return PHYS_TO_DMAP(start) here and not allocate any
1182  * via (*virtp), but then kmem from userland and kernel dumps won't
1183  * have access to the related pointers.
1184  */
1185 vm_offset_t
1186 pmap_map(vm_offset_t *virtp, vm_paddr_t start, vm_paddr_t end, int prot)
1187 {
1188 	vm_offset_t va;
1189 	vm_offset_t va_start;
1190 
1191 	/*return PHYS_TO_DMAP(start);*/
1192 
1193 	va_start = *virtp;
1194 	va = va_start;
1195 
1196 	while (start < end) {
1197 		pmap_kenter_quick(va, start);
1198 		va += PAGE_SIZE;
1199 		start += PAGE_SIZE;
1200 	}
1201 	*virtp = va;
1202 	return va_start;
1203 }
1204 
1205 
1206 /*
1207  * Add a list of wired pages to the kva
1208  * this routine is only used for temporary
1209  * kernel mappings that do not need to have
1210  * page modification or references recorded.
1211  * Note that old mappings are simply written
1212  * over.  The page *must* be wired.
1213  */
1214 void
1215 pmap_qenter(vm_offset_t va, vm_page_t *m, int count)
1216 {
1217 	vm_offset_t end_va;
1218 
1219 	end_va = va + count * PAGE_SIZE;
1220 
1221 	while (va < end_va) {
1222 		pt_entry_t *pte;
1223 
1224 		pte = vtopte(va);
1225 		*pte = VM_PAGE_TO_PHYS(*m) | PG_RW | PG_V | pgeflag;
1226 		cpu_invlpg((void *)va);
1227 		va += PAGE_SIZE;
1228 		m++;
1229 	}
1230 	smp_invltlb();
1231 }
1232 
1233 /*
1234  * This routine jerks page mappings from the
1235  * kernel -- it is meant only for temporary mappings.
1236  *
1237  * MPSAFE, INTERRUPT SAFE (cluster callback)
1238  */
1239 void
1240 pmap_qremove(vm_offset_t va, int count)
1241 {
1242 	vm_offset_t end_va;
1243 
1244 	end_va = va + count * PAGE_SIZE;
1245 
1246 	while (va < end_va) {
1247 		pt_entry_t *pte;
1248 
1249 		pte = vtopte(va);
1250 		(void)pte_load_clear(pte);
1251 		cpu_invlpg((void *)va);
1252 		va += PAGE_SIZE;
1253 	}
1254 	smp_invltlb();
1255 }
1256 
1257 /*
1258  * Create a new thread and optionally associate it with a (new) process.
1259  * NOTE! the new thread's cpu may not equal the current cpu.
1260  */
1261 void
1262 pmap_init_thread(thread_t td)
1263 {
1264 	/* enforce pcb placement & alignment */
1265 	td->td_pcb = (struct pcb *)(td->td_kstack + td->td_kstack_size) - 1;
1266 	td->td_pcb = (struct pcb *)((intptr_t)td->td_pcb & ~(intptr_t)0xF);
1267 	td->td_savefpu = &td->td_pcb->pcb_save;
1268 	td->td_sp = (char *)td->td_pcb;	/* no -16 */
1269 }
1270 
1271 /*
1272  * This routine directly affects the fork perf for a process.
1273  */
1274 void
1275 pmap_init_proc(struct proc *p)
1276 {
1277 }
1278 
1279 /*
1280  * Initialize pmap0/vmspace0.  This pmap is not added to pmap_list because
1281  * it, and IdlePTD, represents the template used to update all other pmaps.
1282  *
1283  * On architectures where the kernel pmap is not integrated into the user
1284  * process pmap, this pmap represents the process pmap, not the kernel pmap.
1285  * kernel_pmap should be used to directly access the kernel_pmap.
1286  */
1287 void
1288 pmap_pinit0(struct pmap *pmap)
1289 {
1290 	pmap->pm_pml4 = (pml4_entry_t *)(PTOV_OFFSET + KPML4phys);
1291 	pmap->pm_count = 1;
1292 	pmap->pm_active = 0;
1293 	pmap->pm_pvhint = NULL;
1294 	RB_INIT(&pmap->pm_pvroot);
1295 	spin_init(&pmap->pm_spin);
1296 	lwkt_token_init(&pmap->pm_token, "pmap_tok");
1297 	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
1298 }
1299 
1300 /*
1301  * Initialize a preallocated and zeroed pmap structure,
1302  * such as one in a vmspace structure.
1303  */
1304 void
1305 pmap_pinit(struct pmap *pmap)
1306 {
1307 	pv_entry_t pv;
1308 	int j;
1309 
1310 	/*
1311 	 * Misc initialization
1312 	 */
1313 	pmap->pm_count = 1;
1314 	pmap->pm_active = 0;
1315 	pmap->pm_pvhint = NULL;
1316 	if (pmap->pm_pmlpv == NULL) {
1317 		RB_INIT(&pmap->pm_pvroot);
1318 		bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
1319 		spin_init(&pmap->pm_spin);
1320 		lwkt_token_init(&pmap->pm_token, "pmap_tok");
1321 	}
1322 
1323 	/*
1324 	 * No need to allocate page table space yet but we do need a valid
1325 	 * page directory table.
1326 	 */
1327 	if (pmap->pm_pml4 == NULL) {
1328 		pmap->pm_pml4 =
1329 		    (pml4_entry_t *)kmem_alloc_pageable(&kernel_map, PAGE_SIZE);
1330 	}
1331 
1332 	/*
1333 	 * Allocate the page directory page, which wires it even though
1334 	 * it isn't being entered into some higher level page table (it
1335 	 * being the highest level).  If one is already cached we don't
1336 	 * have to do anything.
1337 	 */
1338 	if ((pv = pmap->pm_pmlpv) == NULL) {
1339 		pv = pmap_allocpte(pmap, pmap_pml4_pindex(), NULL);
1340 		pmap->pm_pmlpv = pv;
1341 		pmap_kenter((vm_offset_t)pmap->pm_pml4,
1342 			    VM_PAGE_TO_PHYS(pv->pv_m));
1343 		pv_put(pv);
1344 
1345 		/*
1346 		 * Install DMAP and KMAP.
1347 		 */
1348 		for (j = 0; j < NDMPML4E; ++j) {
1349 			pmap->pm_pml4[DMPML4I + j] =
1350 				(DMPDPphys + ((vm_paddr_t)j << PML4SHIFT)) |
1351 				PG_RW | PG_V | PG_U;
1352 		}
1353 		pmap->pm_pml4[KPML4I] = KPDPphys | PG_RW | PG_V | PG_U;
1354 
1355 		/*
1356 		 * install self-referential address mapping entry
1357 		 */
1358 		pmap->pm_pml4[PML4PML4I] = VM_PAGE_TO_PHYS(pv->pv_m) |
1359 					   PG_V | PG_RW | PG_A | PG_M;
1360 	} else {
1361 		KKASSERT(pv->pv_m->flags & PG_MAPPED);
1362 		KKASSERT(pv->pv_m->flags & PG_WRITEABLE);
1363 	}
1364 	KKASSERT(pmap->pm_pml4[255] == 0);
1365 	KKASSERT(RB_ROOT(&pmap->pm_pvroot) == pv);
1366 	KKASSERT(pv->pv_entry.rbe_left == NULL);
1367 	KKASSERT(pv->pv_entry.rbe_right == NULL);
1368 }
1369 
1370 /*
1371  * Clean up a pmap structure so it can be physically freed.  This routine
1372  * is called by the vmspace dtor function.  A great deal of pmap data is
1373  * left passively mapped to improve vmspace management so we have a bit
1374  * of cleanup work to do here.
1375  */
1376 void
1377 pmap_puninit(pmap_t pmap)
1378 {
1379 	pv_entry_t pv;
1380 	vm_page_t p;
1381 
1382 	KKASSERT(pmap->pm_active == 0);
1383 	if ((pv = pmap->pm_pmlpv) != NULL) {
1384 		if (pv_hold_try(pv) == 0)
1385 			pv_lock(pv);
1386 		p = pmap_remove_pv_page(pv);
1387 		pv_free(pv);
1388 		pmap_kremove((vm_offset_t)pmap->pm_pml4);
1389 		vm_page_busy_wait(p, FALSE, "pgpun");
1390 		KKASSERT(p->flags & (PG_FICTITIOUS|PG_UNMANAGED));
1391 		vm_page_unwire(p, 0);
1392 		vm_page_flag_clear(p, PG_MAPPED | PG_WRITEABLE);
1393 
1394 		/*
1395 		 * XXX eventually clean out PML4 static entries and
1396 		 * use vm_page_free_zero()
1397 		 */
1398 		vm_page_free(p);
1399 		pmap->pm_pmlpv = NULL;
1400 	}
1401 	if (pmap->pm_pml4) {
1402 		KKASSERT(pmap->pm_pml4 != (void *)(PTOV_OFFSET + KPML4phys));
1403 		kmem_free(&kernel_map, (vm_offset_t)pmap->pm_pml4, PAGE_SIZE);
1404 		pmap->pm_pml4 = NULL;
1405 	}
1406 	KKASSERT(pmap->pm_stats.resident_count == 0);
1407 	KKASSERT(pmap->pm_stats.wired_count == 0);
1408 }
1409 
1410 /*
1411  * Wire in kernel global address entries.  To avoid a race condition
1412  * between pmap initialization and pmap_growkernel, this procedure
1413  * adds the pmap to the master list (which growkernel scans to update),
1414  * then copies the template.
1415  */
1416 void
1417 pmap_pinit2(struct pmap *pmap)
1418 {
1419 	/*
1420 	 * XXX copies current process, does not fill in MPPTDI
1421 	 */
1422 	spin_lock(&pmap_spin);
1423 	TAILQ_INSERT_TAIL(&pmap_list, pmap, pm_pmnode);
1424 	spin_unlock(&pmap_spin);
1425 }
1426 
1427 /*
1428  * This routine is called when various levels in the page table need to
1429  * be populated.  This routine cannot fail.
1430  *
1431  * This function returns two locked pv_entry's, one representing the
1432  * requested pv and one representing the requested pv's parent pv.  If
1433  * the pv did not previously exist it will be mapped into its parent
1434  * and wired, otherwise no additional wire count will be added.
1435  */
1436 static
1437 pv_entry_t
1438 pmap_allocpte(pmap_t pmap, vm_pindex_t ptepindex, pv_entry_t *pvpp)
1439 {
1440 	pt_entry_t *ptep;
1441 	pv_entry_t pv;
1442 	pv_entry_t pvp;
1443 	vm_pindex_t pt_pindex;
1444 	vm_page_t m;
1445 	int isnew;
1446 
1447 	/*
1448 	 * If the pv already exists and we aren't being asked for the
1449 	 * parent page table page we can just return it.  A locked+held pv
1450 	 * is returned.
1451 	 */
1452 	pv = pv_alloc(pmap, ptepindex, &isnew);
1453 	if (isnew == 0 && pvpp == NULL)
1454 		return(pv);
1455 
1456 	/*
1457 	 * This is a new PV, we have to resolve its parent page table and
1458 	 * add an additional wiring to the page if necessary.
1459 	 */
1460 
1461 	/*
1462 	 * Special case terminal PVs.  These are not page table pages so
1463 	 * no vm_page is allocated (the caller supplied the vm_page).  If
1464 	 * pvpp is non-NULL we are being asked to also removed the pt_pv
1465 	 * for this pv.
1466 	 *
1467 	 * Note that pt_pv's are only returned for user VAs. We assert that
1468 	 * a pt_pv is not being requested for kernel VAs.
1469 	 */
1470 	if (ptepindex < pmap_pt_pindex(0)) {
1471 		if (ptepindex >= NUPTE_USER)
1472 			KKASSERT(pvpp == NULL);
1473 		else
1474 			KKASSERT(pvpp != NULL);
1475 		if (pvpp) {
1476 			pt_pindex = NUPTE_TOTAL + (ptepindex >> NPTEPGSHIFT);
1477 			pvp = pmap_allocpte(pmap, pt_pindex, NULL);
1478 			if (isnew)
1479 				vm_page_wire_quick(pvp->pv_m);
1480 			*pvpp = pvp;
1481 		} else {
1482 			pvp = NULL;
1483 		}
1484 		return(pv);
1485 	}
1486 
1487 	/*
1488 	 * Non-terminal PVs allocate a VM page to represent the page table,
1489 	 * so we have to resolve pvp and calculate ptepindex for the pvp
1490 	 * and then for the page table entry index in the pvp for
1491 	 * fall-through.
1492 	 */
1493 	if (ptepindex < pmap_pd_pindex(0)) {
1494 		/*
1495 		 * pv is PT, pvp is PD
1496 		 */
1497 		ptepindex = (ptepindex - pmap_pt_pindex(0)) >> NPDEPGSHIFT;
1498 		ptepindex += NUPTE_TOTAL + NUPT_TOTAL;
1499 		pvp = pmap_allocpte(pmap, ptepindex, NULL);
1500 		if (!isnew)
1501 			goto notnew;
1502 
1503 		/*
1504 		 * PT index in PD
1505 		 */
1506 		ptepindex = pv->pv_pindex - pmap_pt_pindex(0);
1507 		ptepindex &= ((1ul << NPDEPGSHIFT) - 1);
1508 	} else if (ptepindex < pmap_pdp_pindex(0)) {
1509 		/*
1510 		 * pv is PD, pvp is PDP
1511 		 */
1512 		ptepindex = (ptepindex - pmap_pd_pindex(0)) >> NPDPEPGSHIFT;
1513 		ptepindex += NUPTE_TOTAL + NUPT_TOTAL + NUPD_TOTAL;
1514 		pvp = pmap_allocpte(pmap, ptepindex, NULL);
1515 		if (!isnew)
1516 			goto notnew;
1517 
1518 		/*
1519 		 * PD index in PDP
1520 		 */
1521 		ptepindex = pv->pv_pindex - pmap_pd_pindex(0);
1522 		ptepindex &= ((1ul << NPDPEPGSHIFT) - 1);
1523 	} else if (ptepindex < pmap_pml4_pindex()) {
1524 		/*
1525 		 * pv is PDP, pvp is the root pml4 table
1526 		 */
1527 		pvp = pmap_allocpte(pmap, pmap_pml4_pindex(), NULL);
1528 		if (!isnew)
1529 			goto notnew;
1530 
1531 		/*
1532 		 * PDP index in PML4
1533 		 */
1534 		ptepindex = pv->pv_pindex - pmap_pdp_pindex(0);
1535 		ptepindex &= ((1ul << NPML4EPGSHIFT) - 1);
1536 	} else {
1537 		/*
1538 		 * pv represents the top-level PML4, there is no parent.
1539 		 */
1540 		pvp = NULL;
1541 		if (!isnew)
1542 			goto notnew;
1543 	}
1544 
1545 	/*
1546 	 * This code is only reached if isnew is TRUE and this is not a
1547 	 * terminal PV.  We need to allocate a vm_page for the page table
1548 	 * at this level and enter it into the parent page table.
1549 	 *
1550 	 * page table pages are marked PG_WRITEABLE and PG_MAPPED.
1551 	 */
1552 	for (;;) {
1553 		m = vm_page_alloc(NULL, pv->pv_pindex,
1554 				  VM_ALLOC_NORMAL | VM_ALLOC_SYSTEM |
1555 				  VM_ALLOC_INTERRUPT);
1556 		if (m)
1557 			break;
1558 		vm_wait(0);
1559 	}
1560 	vm_page_spin_lock(m);
1561 	TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
1562 	pv->pv_m = m;
1563 	vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE);
1564 	vm_page_spin_unlock(m);
1565 	vm_page_unmanage(m);	/* m must be spinunlocked */
1566 
1567 	if ((m->flags & PG_ZERO) == 0) {
1568 		pmap_zero_page(VM_PAGE_TO_PHYS(m));
1569 	}
1570 #ifdef PMAP_DEBUG
1571 	else {
1572 		pmap_page_assertzero(VM_PAGE_TO_PHYS(m));
1573 	}
1574 #endif
1575 	m->valid = VM_PAGE_BITS_ALL;
1576 	vm_page_flag_clear(m, PG_ZERO);
1577 	vm_page_wire(m);	/* wire for mapping in parent */
1578 
1579 	/*
1580 	 * Wire the page into pvp, bump the wire-count for pvp's page table
1581 	 * page.  Bump the resident_count for the pmap.  There is no pvp
1582 	 * for the top level, address the pm_pml4[] array directly.
1583 	 *
1584 	 * If the caller wants the parent we return it, otherwise
1585 	 * we just put it away.
1586 	 *
1587 	 * No interlock is needed for pte 0 -> non-zero.
1588 	 */
1589 	if (pvp) {
1590 		vm_page_wire_quick(pvp->pv_m);
1591 		ptep = pv_pte_lookup(pvp, ptepindex);
1592 		KKASSERT((*ptep & PG_V) == 0);
1593 		*ptep = VM_PAGE_TO_PHYS(m) | (PG_U | PG_RW | PG_V |
1594 					      PG_A | PG_M);
1595 	}
1596 	vm_page_wakeup(m);
1597 notnew:
1598 	if (pvpp)
1599 		*pvpp = pvp;
1600 	else if (pvp)
1601 		pv_put(pvp);
1602 	return (pv);
1603 }
1604 
1605 /*
1606  * Release any resources held by the given physical map.
1607  *
1608  * Called when a pmap initialized by pmap_pinit is being released.  Should
1609  * only be called if the map contains no valid mappings.
1610  *
1611  * Caller must hold pmap->pm_token
1612  */
1613 struct pmap_release_info {
1614 	pmap_t	pmap;
1615 	int	retry;
1616 };
1617 
1618 static int pmap_release_callback(pv_entry_t pv, void *data);
1619 
1620 void
1621 pmap_release(struct pmap *pmap)
1622 {
1623 	struct pmap_release_info info;
1624 
1625 	KASSERT(pmap->pm_active == 0,
1626 		("pmap still active! %016jx", (uintmax_t)pmap->pm_active));
1627 
1628 	spin_lock(&pmap_spin);
1629 	TAILQ_REMOVE(&pmap_list, pmap, pm_pmnode);
1630 	spin_unlock(&pmap_spin);
1631 
1632 	/*
1633 	 * Pull pv's off the RB tree in order from low to high and release
1634 	 * each page.
1635 	 */
1636 	info.pmap = pmap;
1637 	do {
1638 		info.retry = 0;
1639 		spin_lock(&pmap->pm_spin);
1640 		RB_SCAN(pv_entry_rb_tree, &pmap->pm_pvroot, NULL,
1641 			pmap_release_callback, &info);
1642 		spin_unlock(&pmap->pm_spin);
1643 	} while (info.retry);
1644 
1645 
1646 	/*
1647 	 * One resident page (the pml4 page) should remain.
1648 	 * No wired pages should remain.
1649 	 */
1650 	KKASSERT(pmap->pm_stats.resident_count == 1);
1651 	KKASSERT(pmap->pm_stats.wired_count == 0);
1652 }
1653 
1654 static int
1655 pmap_release_callback(pv_entry_t pv, void *data)
1656 {
1657 	struct pmap_release_info *info = data;
1658 	pmap_t pmap = info->pmap;
1659 	vm_page_t p;
1660 
1661 	if (pv_hold_try(pv)) {
1662 		spin_unlock(&pmap->pm_spin);
1663 	} else {
1664 		spin_unlock(&pmap->pm_spin);
1665 		pv_lock(pv);
1666 		if (pv->pv_pmap != pmap) {
1667 			pv_put(pv);
1668 			spin_lock(&pmap->pm_spin);
1669 			info->retry = 1;
1670 			return(-1);
1671 		}
1672 	}
1673 
1674 	/*
1675 	 * The pmap is currently not spinlocked, pv is held+locked.
1676 	 * Remove the pv's page from its parent's page table.  The
1677 	 * parent's page table page's wire_count will be decremented.
1678 	 */
1679 	pmap_remove_pv_pte(pv, NULL, NULL);
1680 
1681 	/*
1682 	 * Terminal pvs are unhooked from their vm_pages.  Because
1683 	 * terminal pages aren't page table pages they aren't wired
1684 	 * by us, so we have to be sure not to unwire them either.
1685 	 */
1686 	if (pv->pv_pindex < pmap_pt_pindex(0)) {
1687 		pmap_remove_pv_page(pv);
1688 		goto skip;
1689 	}
1690 
1691 	/*
1692 	 * We leave the top-level page table page cached, wired, and
1693 	 * mapped in the pmap until the dtor function (pmap_puninit())
1694 	 * gets called.
1695 	 *
1696 	 * Since we are leaving the top-level pv intact we need
1697 	 * to break out of what would otherwise be an infinite loop.
1698 	 */
1699 	if (pv->pv_pindex == pmap_pml4_pindex()) {
1700 		pv_put(pv);
1701 		spin_lock(&pmap->pm_spin);
1702 		return(-1);
1703 	}
1704 
1705 	/*
1706 	 * For page table pages (other than the top-level page),
1707 	 * remove and free the vm_page.  The representitive mapping
1708 	 * removed above by pmap_remove_pv_pte() did not undo the
1709 	 * last wire_count so we have to do that as well.
1710 	 */
1711 	p = pmap_remove_pv_page(pv);
1712 	vm_page_busy_wait(p, FALSE, "pmaprl");
1713 	if (p->wire_count != 1) {
1714 		kprintf("p->wire_count was %016lx %d\n",
1715 			pv->pv_pindex, p->wire_count);
1716 	}
1717 	KKASSERT(p->wire_count == 1);
1718 	KKASSERT(p->flags & PG_UNMANAGED);
1719 
1720 	vm_page_unwire(p, 0);
1721 	KKASSERT(p->wire_count == 0);
1722 	/* JG eventually revert to using vm_page_free_zero() */
1723 	vm_page_free(p);
1724 skip:
1725 	pv_free(pv);
1726 	spin_lock(&pmap->pm_spin);
1727 	return(0);
1728 }
1729 
1730 /*
1731  * This function will remove the pte associated with a pv from its parent.
1732  * Terminal pv's are supported.  The removal will be interlocked if info
1733  * is non-NULL.  The caller must dispose of pv instead of just unlocking
1734  * it.
1735  *
1736  * The wire count will be dropped on the parent page table.  The wire
1737  * count on the page being removed (pv->pv_m) from the parent page table
1738  * is NOT touched.  Note that terminal pages will not have any additional
1739  * wire counts while page table pages will have at least one representing
1740  * the mapping, plus others representing sub-mappings.
1741  *
1742  * NOTE: Cannot be called on kernel page table pages, only KVM terminal
1743  *	 pages and user page table and terminal pages.
1744  *
1745  * The pv must be locked.
1746  *
1747  * XXX must lock parent pv's if they exist to remove pte XXX
1748  */
1749 static
1750 void
1751 pmap_remove_pv_pte(pv_entry_t pv, pv_entry_t pvp, struct pmap_inval_info *info)
1752 {
1753 	vm_pindex_t ptepindex = pv->pv_pindex;
1754 	pmap_t pmap = pv->pv_pmap;
1755 	vm_page_t p;
1756 	int gotpvp = 0;
1757 
1758 	KKASSERT(pmap);
1759 
1760 	if (ptepindex == pmap_pml4_pindex()) {
1761 		/*
1762 		 * We are the top level pml4 table, there is no parent.
1763 		 */
1764 		p = pmap->pm_pmlpv->pv_m;
1765 	} else if (ptepindex >= pmap_pdp_pindex(0)) {
1766 		/*
1767 		 * Remove a PDP page from the pml4e.  This can only occur
1768 		 * with user page tables.  We do not have to lock the
1769 		 * pml4 PV so just ignore pvp.
1770 		 */
1771 		vm_pindex_t pml4_pindex;
1772 		vm_pindex_t pdp_index;
1773 		pml4_entry_t *pdp;
1774 
1775 		pdp_index = ptepindex - pmap_pdp_pindex(0);
1776 		if (pvp == NULL) {
1777 			pml4_pindex = pmap_pml4_pindex();
1778 			pvp = pv_get(pv->pv_pmap, pml4_pindex);
1779 			gotpvp = 1;
1780 		}
1781 		pdp = &pmap->pm_pml4[pdp_index & ((1ul << NPML4EPGSHIFT) - 1)];
1782 		KKASSERT((*pdp & PG_V) != 0);
1783 		p = PHYS_TO_VM_PAGE(*pdp & PG_FRAME);
1784 		*pdp = 0;
1785 		KKASSERT(info == NULL);
1786 	} else if (ptepindex >= pmap_pd_pindex(0)) {
1787 		/*
1788 		 *  Remove a PD page from the pdp
1789 		 */
1790 		vm_pindex_t pdp_pindex;
1791 		vm_pindex_t pd_index;
1792 		pdp_entry_t *pd;
1793 
1794 		pd_index = ptepindex - pmap_pd_pindex(0);
1795 
1796 		if (pvp == NULL) {
1797 			pdp_pindex = NUPTE_TOTAL + NUPT_TOTAL + NUPD_TOTAL +
1798 				     (pd_index >> NPML4EPGSHIFT);
1799 			pvp = pv_get(pv->pv_pmap, pdp_pindex);
1800 			gotpvp = 1;
1801 		}
1802 		pd = pv_pte_lookup(pvp, pd_index & ((1ul << NPDPEPGSHIFT) - 1));
1803 		KKASSERT((*pd & PG_V) != 0);
1804 		p = PHYS_TO_VM_PAGE(*pd & PG_FRAME);
1805 		*pd = 0;
1806 		KKASSERT(info == NULL);
1807 	} else if (ptepindex >= pmap_pt_pindex(0)) {
1808 		/*
1809 		 *  Remove a PT page from the pd
1810 		 */
1811 		vm_pindex_t pd_pindex;
1812 		vm_pindex_t pt_index;
1813 		pd_entry_t *pt;
1814 
1815 		pt_index = ptepindex - pmap_pt_pindex(0);
1816 
1817 		if (pvp == NULL) {
1818 			pd_pindex = NUPTE_TOTAL + NUPT_TOTAL +
1819 				    (pt_index >> NPDPEPGSHIFT);
1820 			pvp = pv_get(pv->pv_pmap, pd_pindex);
1821 			gotpvp = 1;
1822 		}
1823 		pt = pv_pte_lookup(pvp, pt_index & ((1ul << NPDPEPGSHIFT) - 1));
1824 		KKASSERT((*pt & PG_V) != 0);
1825 		p = PHYS_TO_VM_PAGE(*pt & PG_FRAME);
1826 		*pt = 0;
1827 		KKASSERT(info == NULL);
1828 	} else {
1829 		/*
1830 		 * Remove a PTE from the PT page
1831 		 *
1832 		 * NOTE: pv's must be locked bottom-up to avoid deadlocking.
1833 		 *	 pv is a pte_pv so we can safely lock pt_pv.
1834 		 */
1835 		vm_pindex_t pt_pindex;
1836 		pt_entry_t *ptep;
1837 		pt_entry_t pte;
1838 		vm_offset_t va;
1839 
1840 		pt_pindex = ptepindex >> NPTEPGSHIFT;
1841 		va = (vm_offset_t)ptepindex << PAGE_SHIFT;
1842 
1843 		if (ptepindex >= NUPTE_USER) {
1844 			ptep = vtopte(ptepindex << PAGE_SHIFT);
1845 			KKASSERT(pvp == NULL);
1846 		} else {
1847 			if (pvp == NULL) {
1848 				pt_pindex = NUPTE_TOTAL +
1849 					    (ptepindex >> NPDPEPGSHIFT);
1850 				pvp = pv_get(pv->pv_pmap, pt_pindex);
1851 				gotpvp = 1;
1852 			}
1853 			ptep = pv_pte_lookup(pvp, ptepindex &
1854 						  ((1ul << NPDPEPGSHIFT) - 1));
1855 		}
1856 
1857 		if (info)
1858 			pmap_inval_interlock(info, pmap, va);
1859 		pte = pte_load_clear(ptep);
1860 		if (info)
1861 			pmap_inval_deinterlock(info, pmap);
1862 		else
1863 			cpu_invlpg((void *)va);
1864 
1865 		/*
1866 		 * Now update the vm_page_t
1867 		 */
1868 		if ((pte & (PG_MANAGED|PG_V)) != (PG_MANAGED|PG_V)) {
1869 			kprintf("remove_pte badpte %016lx %016lx %d\n",
1870 				pte, pv->pv_pindex,
1871 				pv->pv_pindex < pmap_pt_pindex(0));
1872 		}
1873 		/*KKASSERT((pte & (PG_MANAGED|PG_V)) == (PG_MANAGED|PG_V));*/
1874 		p = PHYS_TO_VM_PAGE(pte & PG_FRAME);
1875 
1876 		if (pte & PG_M) {
1877 			if (pmap_track_modified(ptepindex))
1878 				vm_page_dirty(p);
1879 		}
1880 		if (pte & PG_A) {
1881 			vm_page_flag_set(p, PG_REFERENCED);
1882 		}
1883 		if (pte & PG_W)
1884 			atomic_add_long(&pmap->pm_stats.wired_count, -1);
1885 		if (pte & PG_G)
1886 			cpu_invlpg((void *)va);
1887 	}
1888 
1889 	/*
1890 	 * Unwire the parent page table page.  The wire_count cannot go below
1891 	 * 1 here because the parent page table page is itself still mapped.
1892 	 *
1893 	 * XXX remove the assertions later.
1894 	 */
1895 	KKASSERT(pv->pv_m == p);
1896 	if (pvp && vm_page_unwire_quick(pvp->pv_m))
1897 		panic("pmap_remove_pv_pte: Insufficient wire_count");
1898 
1899 	if (gotpvp)
1900 		pv_put(pvp);
1901 }
1902 
1903 static
1904 vm_page_t
1905 pmap_remove_pv_page(pv_entry_t pv)
1906 {
1907 	vm_page_t m;
1908 
1909 	m = pv->pv_m;
1910 	KKASSERT(m);
1911 	vm_page_spin_lock(m);
1912 	pv->pv_m = NULL;
1913 	TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
1914 	/*
1915 	if (m->object)
1916 		atomic_add_int(&m->object->agg_pv_list_count, -1);
1917 	*/
1918 	if (TAILQ_EMPTY(&m->md.pv_list))
1919 		vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
1920 	vm_page_spin_unlock(m);
1921 	return(m);
1922 }
1923 
1924 /*
1925  * Grow the number of kernel page table entries, if needed.
1926  *
1927  * This routine is always called to validate any address space
1928  * beyond KERNBASE (for kldloads).  kernel_vm_end only governs the address
1929  * space below KERNBASE.
1930  */
1931 void
1932 pmap_growkernel(vm_offset_t kstart, vm_offset_t kend)
1933 {
1934 	vm_paddr_t paddr;
1935 	vm_offset_t ptppaddr;
1936 	vm_page_t nkpg;
1937 	pd_entry_t *pt, newpt;
1938 	pdp_entry_t newpd;
1939 	int update_kernel_vm_end;
1940 
1941 	/*
1942 	 * bootstrap kernel_vm_end on first real VM use
1943 	 */
1944 	if (kernel_vm_end == 0) {
1945 		kernel_vm_end = VM_MIN_KERNEL_ADDRESS;
1946 		nkpt = 0;
1947 		while ((*pmap_pt(&kernel_pmap, kernel_vm_end) & PG_V) != 0) {
1948 			kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) &
1949 					~(PAGE_SIZE * NPTEPG - 1);
1950 			nkpt++;
1951 			if (kernel_vm_end - 1 >= kernel_map.max_offset) {
1952 				kernel_vm_end = kernel_map.max_offset;
1953 				break;
1954 			}
1955 		}
1956 	}
1957 
1958 	/*
1959 	 * Fill in the gaps.  kernel_vm_end is only adjusted for ranges
1960 	 * below KERNBASE.  Ranges above KERNBASE are kldloaded and we
1961 	 * do not want to force-fill 128G worth of page tables.
1962 	 */
1963 	if (kstart < KERNBASE) {
1964 		if (kstart > kernel_vm_end)
1965 			kstart = kernel_vm_end;
1966 		KKASSERT(kend <= KERNBASE);
1967 		update_kernel_vm_end = 1;
1968 	} else {
1969 		update_kernel_vm_end = 0;
1970 	}
1971 
1972 	kstart = rounddown2(kstart, PAGE_SIZE * NPTEPG);
1973 	kend = roundup2(kend, PAGE_SIZE * NPTEPG);
1974 
1975 	if (kend - 1 >= kernel_map.max_offset)
1976 		kend = kernel_map.max_offset;
1977 
1978 	while (kstart < kend) {
1979 		pt = pmap_pt(&kernel_pmap, kstart);
1980 		if (pt == NULL) {
1981 			/* We need a new PDP entry */
1982 			nkpg = vm_page_alloc(NULL, nkpt,
1983 			                     VM_ALLOC_NORMAL |
1984 					     VM_ALLOC_SYSTEM |
1985 					     VM_ALLOC_INTERRUPT);
1986 			if (nkpg == NULL) {
1987 				panic("pmap_growkernel: no memory to grow "
1988 				      "kernel");
1989 			}
1990 			paddr = VM_PAGE_TO_PHYS(nkpg);
1991 			if ((nkpg->flags & PG_ZERO) == 0)
1992 				pmap_zero_page(paddr);
1993 			vm_page_flag_clear(nkpg, PG_ZERO);
1994 			newpd = (pdp_entry_t)
1995 				(paddr | PG_V | PG_RW | PG_A | PG_M);
1996 			*pmap_pd(&kernel_pmap, kstart) = newpd;
1997 			nkpt++;
1998 			continue; /* try again */
1999 		}
2000 		if ((*pt & PG_V) != 0) {
2001 			kstart = (kstart + PAGE_SIZE * NPTEPG) &
2002 				 ~(PAGE_SIZE * NPTEPG - 1);
2003 			if (kstart - 1 >= kernel_map.max_offset) {
2004 				kstart = kernel_map.max_offset;
2005 				break;
2006 			}
2007 			continue;
2008 		}
2009 
2010 		/*
2011 		 * This index is bogus, but out of the way
2012 		 */
2013 		nkpg = vm_page_alloc(NULL, nkpt,
2014 				     VM_ALLOC_NORMAL |
2015 				     VM_ALLOC_SYSTEM |
2016 				     VM_ALLOC_INTERRUPT);
2017 		if (nkpg == NULL)
2018 			panic("pmap_growkernel: no memory to grow kernel");
2019 
2020 		vm_page_wire(nkpg);
2021 		ptppaddr = VM_PAGE_TO_PHYS(nkpg);
2022 		pmap_zero_page(ptppaddr);
2023 		vm_page_flag_clear(nkpg, PG_ZERO);
2024 		newpt = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M);
2025 		*pmap_pt(&kernel_pmap, kstart) = newpt;
2026 		nkpt++;
2027 
2028 		kstart = (kstart + PAGE_SIZE * NPTEPG) &
2029 			  ~(PAGE_SIZE * NPTEPG - 1);
2030 
2031 		if (kstart - 1 >= kernel_map.max_offset) {
2032 			kstart = kernel_map.max_offset;
2033 			break;
2034 		}
2035 	}
2036 
2037 	/*
2038 	 * Only update kernel_vm_end for areas below KERNBASE.
2039 	 */
2040 	if (update_kernel_vm_end && kernel_vm_end < kstart)
2041 		kernel_vm_end = kstart;
2042 }
2043 
2044 /*
2045  *	Retire the given physical map from service.
2046  *	Should only be called if the map contains
2047  *	no valid mappings.
2048  */
2049 void
2050 pmap_destroy(pmap_t pmap)
2051 {
2052 	int count;
2053 
2054 	if (pmap == NULL)
2055 		return;
2056 
2057 	lwkt_gettoken(&pmap->pm_token);
2058 	count = --pmap->pm_count;
2059 	if (count == 0) {
2060 		pmap_release(pmap);	/* eats pm_token */
2061 		panic("destroying a pmap is not yet implemented");
2062 	}
2063 	lwkt_reltoken(&pmap->pm_token);
2064 }
2065 
2066 /*
2067  *	Add a reference to the specified pmap.
2068  */
2069 void
2070 pmap_reference(pmap_t pmap)
2071 {
2072 	if (pmap != NULL) {
2073 		lwkt_gettoken(&pmap->pm_token);
2074 		pmap->pm_count++;
2075 		lwkt_reltoken(&pmap->pm_token);
2076 	}
2077 }
2078 
2079 /***************************************************
2080  * page management routines.
2081  ***************************************************/
2082 
2083 /*
2084  * Hold a pv without locking it
2085  */
2086 static void
2087 pv_hold(pv_entry_t pv)
2088 {
2089 	u_int count;
2090 
2091 	if (atomic_cmpset_int(&pv->pv_hold, 0, 1))
2092 		return;
2093 
2094 	for (;;) {
2095 		count = pv->pv_hold;
2096 		cpu_ccfence();
2097 		if (atomic_cmpset_int(&pv->pv_hold, count, count + 1))
2098 			return;
2099 		/* retry */
2100 	}
2101 }
2102 
2103 /*
2104  * Hold a pv_entry, preventing its destruction.  TRUE is returned if the pv
2105  * was successfully locked, FALSE if it wasn't.  The caller must dispose of
2106  * the pv properly.
2107  *
2108  * Either the pmap->pm_spin or the related vm_page_spin (if traversing a
2109  * pv list via its page) must be held by the caller.
2110  */
2111 static int
2112 _pv_hold_try(pv_entry_t pv PMAP_DEBUG_DECL)
2113 {
2114 	u_int count;
2115 
2116 	if (atomic_cmpset_int(&pv->pv_hold, 0, PV_HOLD_LOCKED | 1)) {
2117 #ifdef PMAP_DEBUG
2118 		pv->pv_func = func;
2119 		pv->pv_line = lineno;
2120 #endif
2121 		return TRUE;
2122 	}
2123 
2124 	for (;;) {
2125 		count = pv->pv_hold;
2126 		cpu_ccfence();
2127 		if ((count & PV_HOLD_LOCKED) == 0) {
2128 			if (atomic_cmpset_int(&pv->pv_hold, count,
2129 					      (count + 1) | PV_HOLD_LOCKED)) {
2130 #ifdef PMAP_DEBUG
2131 				pv->pv_func = func;
2132 				pv->pv_line = lineno;
2133 #endif
2134 				return TRUE;
2135 			}
2136 		} else {
2137 			if (atomic_cmpset_int(&pv->pv_hold, count, count + 1))
2138 				return FALSE;
2139 		}
2140 		/* retry */
2141 	}
2142 }
2143 
2144 /*
2145  * Drop a previously held pv_entry which could not be locked, allowing its
2146  * destruction.
2147  *
2148  * Must not be called with a spinlock held as we might zfree() the pv if it
2149  * is no longer associated with a pmap and this was the last hold count.
2150  */
2151 static void
2152 pv_drop(pv_entry_t pv)
2153 {
2154 	u_int count;
2155 
2156 	if (atomic_cmpset_int(&pv->pv_hold, 1, 0)) {
2157 		if (pv->pv_pmap == NULL)
2158 			zfree(pvzone, pv);
2159 		return;
2160 	}
2161 
2162 	for (;;) {
2163 		count = pv->pv_hold;
2164 		cpu_ccfence();
2165 		KKASSERT((count & PV_HOLD_MASK) > 0);
2166 		KKASSERT((count & (PV_HOLD_LOCKED | PV_HOLD_MASK)) !=
2167 			 (PV_HOLD_LOCKED | 1));
2168 		if (atomic_cmpset_int(&pv->pv_hold, count, count - 1)) {
2169 			if (count == 1 && pv->pv_pmap == NULL)
2170 				zfree(pvzone, pv);
2171 			return;
2172 		}
2173 		/* retry */
2174 	}
2175 }
2176 
2177 /*
2178  * Find or allocate the requested PV entry, returning a locked pv
2179  */
2180 static
2181 pv_entry_t
2182 _pv_alloc(pmap_t pmap, vm_pindex_t pindex, int *isnew PMAP_DEBUG_DECL)
2183 {
2184 	pv_entry_t pv;
2185 	pv_entry_t pnew = NULL;
2186 
2187 	spin_lock(&pmap->pm_spin);
2188 	for (;;) {
2189 		if ((pv = pmap->pm_pvhint) == NULL || pv->pv_pindex != pindex) {
2190 			pv = pv_entry_rb_tree_RB_LOOKUP(&pmap->pm_pvroot,
2191 							pindex);
2192 		}
2193 		if (pv == NULL) {
2194 			if (pnew == NULL) {
2195 				spin_unlock(&pmap->pm_spin);
2196 				pnew = zalloc(pvzone);
2197 				spin_lock(&pmap->pm_spin);
2198 				continue;
2199 			}
2200 			pnew->pv_pmap = pmap;
2201 			pnew->pv_pindex = pindex;
2202 			pnew->pv_hold = PV_HOLD_LOCKED | 1;
2203 #ifdef PMAP_DEBUG
2204 			pnew->pv_func = func;
2205 			pnew->pv_line = lineno;
2206 #endif
2207 			pv_entry_rb_tree_RB_INSERT(&pmap->pm_pvroot, pnew);
2208 			atomic_add_long(&pmap->pm_stats.resident_count, 1);
2209 			spin_unlock(&pmap->pm_spin);
2210 			*isnew = 1;
2211 			return(pnew);
2212 		}
2213 		if (pnew) {
2214 			spin_unlock(&pmap->pm_spin);
2215 			zfree(pvzone, pnew);
2216 			pnew = NULL;
2217 			spin_lock(&pmap->pm_spin);
2218 			continue;
2219 		}
2220 		if (_pv_hold_try(pv PMAP_DEBUG_COPY)) {
2221 			spin_unlock(&pmap->pm_spin);
2222 			*isnew = 0;
2223 			return(pv);
2224 		}
2225 		spin_unlock(&pmap->pm_spin);
2226 		_pv_lock(pv PMAP_DEBUG_COPY);
2227 		if (pv->pv_pmap == pmap && pv->pv_pindex == pindex) {
2228 			*isnew = 0;
2229 			return(pv);
2230 		}
2231 		pv_put(pv);
2232 		spin_lock(&pmap->pm_spin);
2233 	}
2234 
2235 
2236 }
2237 
2238 /*
2239  * Find the requested PV entry, returning a locked+held pv or NULL
2240  */
2241 static
2242 pv_entry_t
2243 _pv_get(pmap_t pmap, vm_pindex_t pindex PMAP_DEBUG_DECL)
2244 {
2245 	pv_entry_t pv;
2246 
2247 	spin_lock(&pmap->pm_spin);
2248 	for (;;) {
2249 		/*
2250 		 * Shortcut cache
2251 		 */
2252 		if ((pv = pmap->pm_pvhint) == NULL || pv->pv_pindex != pindex) {
2253 			pv = pv_entry_rb_tree_RB_LOOKUP(&pmap->pm_pvroot,
2254 							pindex);
2255 		}
2256 		if (pv == NULL) {
2257 			spin_unlock(&pmap->pm_spin);
2258 			return NULL;
2259 		}
2260 		if (_pv_hold_try(pv PMAP_DEBUG_COPY)) {
2261 			pv_cache(pv, pindex);
2262 			spin_unlock(&pmap->pm_spin);
2263 			return(pv);
2264 		}
2265 		spin_unlock(&pmap->pm_spin);
2266 		_pv_lock(pv PMAP_DEBUG_COPY);
2267 		if (pv->pv_pmap == pmap && pv->pv_pindex == pindex)
2268 			return(pv);
2269 		pv_put(pv);
2270 		spin_lock(&pmap->pm_spin);
2271 	}
2272 }
2273 
2274 /*
2275  * Lookup, hold, and attempt to lock (pmap,pindex).
2276  *
2277  * If the entry does not exist NULL is returned and *errorp is set to 0
2278  *
2279  * If the entry exists and could be successfully locked it is returned and
2280  * errorp is set to 0.
2281  *
2282  * If the entry exists but could NOT be successfully locked it is returned
2283  * held and *errorp is set to 1.
2284  */
2285 static
2286 pv_entry_t
2287 pv_get_try(pmap_t pmap, vm_pindex_t pindex, int *errorp)
2288 {
2289 	pv_entry_t pv;
2290 
2291 	spin_lock(&pmap->pm_spin);
2292 	if ((pv = pmap->pm_pvhint) == NULL || pv->pv_pindex != pindex)
2293 		pv = pv_entry_rb_tree_RB_LOOKUP(&pmap->pm_pvroot, pindex);
2294 	if (pv == NULL) {
2295 		spin_unlock(&pmap->pm_spin);
2296 		*errorp = 0;
2297 		return NULL;
2298 	}
2299 	if (pv_hold_try(pv)) {
2300 		pv_cache(pv, pindex);
2301 		spin_unlock(&pmap->pm_spin);
2302 		*errorp = 0;
2303 		return(pv);	/* lock succeeded */
2304 	}
2305 	spin_unlock(&pmap->pm_spin);
2306 	*errorp = 1;
2307 	return (pv);		/* lock failed */
2308 }
2309 
2310 /*
2311  * Find the requested PV entry, returning a held pv or NULL
2312  */
2313 static
2314 pv_entry_t
2315 pv_find(pmap_t pmap, vm_pindex_t pindex)
2316 {
2317 	pv_entry_t pv;
2318 
2319 	spin_lock(&pmap->pm_spin);
2320 
2321 	if ((pv = pmap->pm_pvhint) == NULL || pv->pv_pindex != pindex)
2322 		pv = pv_entry_rb_tree_RB_LOOKUP(&pmap->pm_pvroot, pindex);
2323 	if (pv == NULL) {
2324 		spin_unlock(&pmap->pm_spin);
2325 		return NULL;
2326 	}
2327 	pv_hold(pv);
2328 	pv_cache(pv, pindex);
2329 	spin_unlock(&pmap->pm_spin);
2330 	return(pv);
2331 }
2332 
2333 /*
2334  * Lock a held pv, keeping the hold count
2335  */
2336 static
2337 void
2338 _pv_lock(pv_entry_t pv PMAP_DEBUG_DECL)
2339 {
2340 	u_int count;
2341 
2342 	for (;;) {
2343 		count = pv->pv_hold;
2344 		cpu_ccfence();
2345 		if ((count & PV_HOLD_LOCKED) == 0) {
2346 			if (atomic_cmpset_int(&pv->pv_hold, count,
2347 					      count | PV_HOLD_LOCKED)) {
2348 #ifdef PMAP_DEBUG
2349 				pv->pv_func = func;
2350 				pv->pv_line = lineno;
2351 #endif
2352 				return;
2353 			}
2354 			continue;
2355 		}
2356 		tsleep_interlock(pv, 0);
2357 		if (atomic_cmpset_int(&pv->pv_hold, count,
2358 				      count | PV_HOLD_WAITING)) {
2359 #ifdef PMAP_DEBUG
2360 			kprintf("pv waiting on %s:%d\n",
2361 					pv->pv_func, pv->pv_line);
2362 #endif
2363 			tsleep(pv, PINTERLOCKED, "pvwait", hz);
2364 		}
2365 		/* retry */
2366 	}
2367 }
2368 
2369 /*
2370  * Unlock a held and locked pv, keeping the hold count.
2371  */
2372 static
2373 void
2374 pv_unlock(pv_entry_t pv)
2375 {
2376 	u_int count;
2377 
2378 	if (atomic_cmpset_int(&pv->pv_hold, PV_HOLD_LOCKED | 1, 1))
2379 		return;
2380 
2381 	for (;;) {
2382 		count = pv->pv_hold;
2383 		cpu_ccfence();
2384 		KKASSERT((count & (PV_HOLD_LOCKED|PV_HOLD_MASK)) >=
2385 			 (PV_HOLD_LOCKED | 1));
2386 		if (atomic_cmpset_int(&pv->pv_hold, count,
2387 				      count &
2388 				      ~(PV_HOLD_LOCKED | PV_HOLD_WAITING))) {
2389 			if (count & PV_HOLD_WAITING)
2390 				wakeup(pv);
2391 			break;
2392 		}
2393 	}
2394 }
2395 
2396 /*
2397  * Unlock and drop a pv.  If the pv is no longer associated with a pmap
2398  * and the hold count drops to zero we will free it.
2399  *
2400  * Caller should not hold any spin locks.  We are protected from hold races
2401  * by virtue of holds only occuring only with a pmap_spin or vm_page_spin
2402  * lock held.  A pv cannot be located otherwise.
2403  */
2404 static
2405 void
2406 pv_put(pv_entry_t pv)
2407 {
2408 	if (atomic_cmpset_int(&pv->pv_hold, PV_HOLD_LOCKED | 1, 0)) {
2409 		if (pv->pv_pmap == NULL)
2410 			zfree(pvzone, pv);
2411 		return;
2412 	}
2413 	pv_unlock(pv);
2414 	pv_drop(pv);
2415 }
2416 
2417 /*
2418  * Unlock, drop, and free a pv, destroying it.  The pv is removed from its
2419  * pmap.  Any pte operations must have already been completed.
2420  */
2421 static
2422 void
2423 pv_free(pv_entry_t pv)
2424 {
2425 	pmap_t pmap;
2426 
2427 	KKASSERT(pv->pv_m == NULL);
2428 	if ((pmap = pv->pv_pmap) != NULL) {
2429 		spin_lock(&pmap->pm_spin);
2430 		pv_entry_rb_tree_RB_REMOVE(&pmap->pm_pvroot, pv);
2431 		if (pmap->pm_pvhint == pv)
2432 			pmap->pm_pvhint = NULL;
2433 		atomic_add_long(&pmap->pm_stats.resident_count, -1);
2434 		pv->pv_pmap = NULL;
2435 		pv->pv_pindex = 0;
2436 		spin_unlock(&pmap->pm_spin);
2437 	}
2438 	pv_put(pv);
2439 }
2440 
2441 /*
2442  * This routine is very drastic, but can save the system
2443  * in a pinch.
2444  */
2445 void
2446 pmap_collect(void)
2447 {
2448 	int i;
2449 	vm_page_t m;
2450 	static int warningdone=0;
2451 
2452 	if (pmap_pagedaemon_waken == 0)
2453 		return;
2454 	pmap_pagedaemon_waken = 0;
2455 	if (warningdone < 5) {
2456 		kprintf("pmap_collect: collecting pv entries -- "
2457 			"suggest increasing PMAP_SHPGPERPROC\n");
2458 		warningdone++;
2459 	}
2460 
2461 	for (i = 0; i < vm_page_array_size; i++) {
2462 		m = &vm_page_array[i];
2463 		if (m->wire_count || m->hold_count)
2464 			continue;
2465 		if (vm_page_busy_try(m, TRUE) == 0) {
2466 			if (m->wire_count == 0 && m->hold_count == 0) {
2467 				pmap_remove_all(m);
2468 			}
2469 			vm_page_wakeup(m);
2470 		}
2471 	}
2472 }
2473 
2474 /*
2475  * Scan the pmap for active page table entries and issue a callback.
2476  * The callback must dispose of pte_pv.
2477  *
2478  * NOTE: Unmanaged page table entries will not have a pte_pv
2479  *
2480  * NOTE: Kernel page table entries will not have a pt_pv.  That is, wiring
2481  *	 counts are not tracked in kernel page table pages.
2482  *
2483  * It is assumed that the start and end are properly rounded to the page size.
2484  */
2485 static void
2486 pmap_scan(struct pmap *pmap, vm_offset_t sva, vm_offset_t eva,
2487 	  void (*func)(pmap_t, struct pmap_inval_info *,
2488 		       pv_entry_t, pv_entry_t, vm_offset_t,
2489 		       pt_entry_t *, void *),
2490 	  void *arg)
2491 {
2492 	pv_entry_t pdp_pv;	/* A page directory page PV */
2493 	pv_entry_t pd_pv;	/* A page directory PV */
2494 	pv_entry_t pt_pv;	/* A page table PV */
2495 	pv_entry_t pte_pv;	/* A page table entry PV */
2496 	pt_entry_t *ptep;
2497 	vm_offset_t va_next;
2498 	struct pmap_inval_info info;
2499 	int error;
2500 
2501 	if (pmap == NULL)
2502 		return;
2503 
2504 	/*
2505 	 * Hold the token for stability; if the pmap is empty we have nothing
2506 	 * to do.
2507 	 */
2508 	lwkt_gettoken(&pmap->pm_token);
2509 #if 0
2510 	if (pmap->pm_stats.resident_count == 0) {
2511 		lwkt_reltoken(&pmap->pm_token);
2512 		return;
2513 	}
2514 #endif
2515 
2516 	pmap_inval_init(&info);
2517 
2518 	/*
2519 	 * Special handling for removing one page, which is a very common
2520 	 * operation (it is?).
2521 	 * NOTE: Locks must be ordered bottom-up. pte,pt,pd,pdp,pml4
2522 	 */
2523 	if (sva + PAGE_SIZE == eva) {
2524 		if (sva >= VM_MAX_USER_ADDRESS) {
2525 			/*
2526 			 * Kernel mappings do not track wire counts on
2527 			 * page table pages.
2528 			 */
2529 			pt_pv = NULL;
2530 			pte_pv = pv_get(pmap, pmap_pte_pindex(sva));
2531 			ptep = vtopte(sva);
2532 		} else {
2533 			/*
2534 			 * User mappings may or may not have a pte_pv but
2535 			 * will always have a pt_pv if the page is present.
2536 			 */
2537 			pte_pv = pv_get(pmap, pmap_pte_pindex(sva));
2538 			pt_pv = pv_get(pmap, pmap_pt_pindex(sva));
2539 			if (pt_pv == NULL) {
2540 				KKASSERT(pte_pv == NULL);
2541 				goto fast_skip;
2542 			}
2543 			ptep = pv_pte_lookup(pt_pv, pmap_pte_index(sva));
2544 		}
2545 		if (*ptep == 0) {
2546 			/*
2547 			 * Unlike the pv_find() case below we actually
2548 			 * acquired a locked pv in this case so any
2549 			 * race should have been resolved.  It is expected
2550 			 * to not exist.
2551 			 */
2552 			KKASSERT(pte_pv == NULL);
2553 		} else if (pte_pv) {
2554 			KASSERT((*ptep & (PG_MANAGED|PG_V)) == (PG_MANAGED|
2555 								PG_V),
2556 				("bad *ptep %016lx sva %016lx pte_pv %p",
2557 				*ptep, sva, pte_pv));
2558 			func(pmap, &info, pte_pv, pt_pv, sva, ptep, arg);
2559 		} else {
2560 			KASSERT((*ptep & (PG_MANAGED|PG_V)) == PG_V,
2561 				("bad *ptep %016lx sva %016lx pte_pv NULL",
2562 				*ptep, sva));
2563 			func(pmap, &info, pte_pv, pt_pv, sva, ptep, arg);
2564 		}
2565 		if (pt_pv)
2566 			pv_put(pt_pv);
2567 fast_skip:
2568 		pmap_inval_done(&info);
2569 		lwkt_reltoken(&pmap->pm_token);
2570 		return;
2571 	}
2572 
2573 	/*
2574 	 * NOTE: kernel mappings do not track page table pages, only
2575 	 * 	 terminal pages.
2576 	 *
2577 	 * NOTE: Locks must be ordered bottom-up. pte,pt,pd,pdp,pml4.
2578 	 *	 However, for the scan to be efficient we try to
2579 	 *	 cache items top-down.
2580 	 */
2581 	pdp_pv = NULL;
2582 	pd_pv = NULL;
2583 	pt_pv = NULL;
2584 
2585 	for (; sva < eva; sva = va_next) {
2586 		lwkt_yield();
2587 		if (sva >= VM_MAX_USER_ADDRESS) {
2588 			if (pt_pv) {
2589 				pv_put(pt_pv);
2590 				pt_pv = NULL;
2591 			}
2592 			goto kernel_skip;
2593 		}
2594 
2595 		/*
2596 		 * PDP cache
2597 		 */
2598 		if (pdp_pv == NULL) {
2599 			pdp_pv = pv_get(pmap, pmap_pdp_pindex(sva));
2600 		} else if (pdp_pv->pv_pindex != pmap_pdp_pindex(sva)) {
2601 			pv_put(pdp_pv);
2602 			pdp_pv = pv_get(pmap, pmap_pdp_pindex(sva));
2603 		}
2604 		if (pdp_pv == NULL) {
2605 			va_next = (sva + NBPML4) & ~PML4MASK;
2606 			if (va_next < sva)
2607 				va_next = eva;
2608 			continue;
2609 		}
2610 
2611 		/*
2612 		 * PD cache
2613 		 */
2614 		if (pd_pv == NULL) {
2615 			if (pdp_pv) {
2616 				pv_put(pdp_pv);
2617 				pdp_pv = NULL;
2618 			}
2619 			pd_pv = pv_get(pmap, pmap_pd_pindex(sva));
2620 		} else if (pd_pv->pv_pindex != pmap_pd_pindex(sva)) {
2621 			pv_put(pd_pv);
2622 			if (pdp_pv) {
2623 				pv_put(pdp_pv);
2624 				pdp_pv = NULL;
2625 			}
2626 			pd_pv = pv_get(pmap, pmap_pd_pindex(sva));
2627 		}
2628 		if (pd_pv == NULL) {
2629 			va_next = (sva + NBPDP) & ~PDPMASK;
2630 			if (va_next < sva)
2631 				va_next = eva;
2632 			continue;
2633 		}
2634 
2635 		/*
2636 		 * PT cache
2637 		 */
2638 		if (pt_pv == NULL) {
2639 			if (pdp_pv) {
2640 				pv_put(pdp_pv);
2641 				pdp_pv = NULL;
2642 			}
2643 			if (pd_pv) {
2644 				pv_put(pd_pv);
2645 				pd_pv = NULL;
2646 			}
2647 			pt_pv = pv_get(pmap, pmap_pt_pindex(sva));
2648 		} else if (pt_pv->pv_pindex != pmap_pt_pindex(sva)) {
2649 			if (pdp_pv) {
2650 				pv_put(pdp_pv);
2651 				pdp_pv = NULL;
2652 			}
2653 			if (pd_pv) {
2654 				pv_put(pd_pv);
2655 				pd_pv = NULL;
2656 			}
2657 			pv_put(pt_pv);
2658 			pt_pv = pv_get(pmap, pmap_pt_pindex(sva));
2659 		}
2660 
2661 		/*
2662 		 * We will scan or skip a page table page so adjust va_next
2663 		 * either way.
2664 		 */
2665 		if (pt_pv == NULL) {
2666 			va_next = (sva + NBPDR) & ~PDRMASK;
2667 			if (va_next < sva)
2668 				va_next = eva;
2669 			continue;
2670 		}
2671 
2672 		/*
2673 		 * From this point in the loop testing pt_pv for non-NULL
2674 		 * means we are in UVM, else if it is NULL we are in KVM.
2675 		 */
2676 kernel_skip:
2677 		va_next = (sva + NBPDR) & ~PDRMASK;
2678 		if (va_next < sva)
2679 			va_next = eva;
2680 
2681 		/*
2682 		 * Limit our scan to either the end of the va represented
2683 		 * by the current page table page, or to the end of the
2684 		 * range being removed.
2685 		 *
2686 		 * Scan the page table for pages.  Some pages may not be
2687 		 * managed (might not have a pv_entry).
2688 		 *
2689 		 * There is no page table management for kernel pages so
2690 		 * pt_pv will be NULL in that case, but otherwise pt_pv
2691 		 * is non-NULL, locked, and referenced.
2692 		 */
2693 		if (va_next > eva)
2694 			va_next = eva;
2695 
2696 		/*
2697 		 * At this point a non-NULL pt_pv means a UVA, and a NULL
2698 		 * pt_pv means a KVA.
2699 		 */
2700 		if (pt_pv)
2701 			ptep = pv_pte_lookup(pt_pv, pmap_pte_index(sva));
2702 		else
2703 			ptep = vtopte(sva);
2704 
2705 		while (sva < va_next) {
2706 			/*
2707 			 * Acquire the related pte_pv, if any.  If *ptep == 0
2708 			 * the related pte_pv should not exist, but if *ptep
2709 			 * is not zero the pte_pv may or may not exist (e.g.
2710 			 * will not exist for an unmanaged page).
2711 			 *
2712 			 * However a multitude of races are possible here.
2713 			 *
2714 			 * In addition, the (pt_pv, pte_pv) lock order is
2715 			 * backwards, so we have to be careful in aquiring
2716 			 * a properly locked pte_pv.
2717 			 */
2718 			lwkt_yield();
2719 			if (pt_pv) {
2720 				pte_pv = pv_get_try(pmap, pmap_pte_pindex(sva),
2721 						    &error);
2722 				if (error) {
2723 					if (pdp_pv) {
2724 						pv_put(pdp_pv);
2725 						pdp_pv = NULL;
2726 					}
2727 					if (pd_pv) {
2728 						pv_put(pd_pv);
2729 						pd_pv = NULL;
2730 					}
2731 					pv_put(pt_pv);	 /* must be non-NULL */
2732 					pt_pv = NULL;
2733 					pv_lock(pte_pv); /* safe to block now */
2734 					pv_put(pte_pv);
2735 					pte_pv = NULL;
2736 					pt_pv = pv_get(pmap,
2737 						       pmap_pt_pindex(sva));
2738 					continue;
2739 				}
2740 			} else {
2741 				pte_pv = pv_get(pmap, pmap_pte_pindex(sva));
2742 			}
2743 
2744 			/*
2745 			 * Ok, if *ptep == 0 we had better NOT have a pte_pv.
2746 			 */
2747 			if (*ptep == 0) {
2748 				if (pte_pv) {
2749 					kprintf("Unexpected non-NULL pte_pv "
2750 						"%p pt_pv %p *ptep = %016lx\n",
2751 						pte_pv, pt_pv, *ptep);
2752 					panic("Unexpected non-NULL pte_pv");
2753 				}
2754 				sva += PAGE_SIZE;
2755 				++ptep;
2756 				continue;
2757 			}
2758 
2759 			/*
2760 			 * Ready for the callback.  The locked pte_pv (if any)
2761 			 * is consumed by the callback.  pte_pv will exist if
2762 			 *  the page is managed, and will not exist if it
2763 			 * isn't.
2764 			 */
2765 			if (pte_pv) {
2766 				KASSERT((*ptep & (PG_MANAGED|PG_V)) ==
2767 					 (PG_MANAGED|PG_V),
2768 					("bad *ptep %016lx sva %016lx "
2769 					 "pte_pv %p",
2770 					 *ptep, sva, pte_pv));
2771 				func(pmap, &info, pte_pv, pt_pv, sva,
2772 				     ptep, arg);
2773 			} else {
2774 				KASSERT((*ptep & (PG_MANAGED|PG_V)) ==
2775 					 PG_V,
2776 					("bad *ptep %016lx sva %016lx "
2777 					 "pte_pv NULL",
2778 					 *ptep, sva));
2779 				func(pmap, &info, pte_pv, pt_pv, sva,
2780 				     ptep, arg);
2781 			}
2782 			pte_pv = NULL;
2783 			sva += PAGE_SIZE;
2784 			++ptep;
2785 		}
2786 	}
2787 	if (pdp_pv) {
2788 		pv_put(pdp_pv);
2789 		pdp_pv = NULL;
2790 	}
2791 	if (pd_pv) {
2792 		pv_put(pd_pv);
2793 		pd_pv = NULL;
2794 	}
2795 	if (pt_pv) {
2796 		pv_put(pt_pv);
2797 		pt_pv = NULL;
2798 	}
2799 	pmap_inval_done(&info);
2800 	lwkt_reltoken(&pmap->pm_token);
2801 }
2802 
2803 void
2804 pmap_remove(struct pmap *pmap, vm_offset_t sva, vm_offset_t eva)
2805 {
2806 	pmap_scan(pmap, sva, eva, pmap_remove_callback, NULL);
2807 }
2808 
2809 static void
2810 pmap_remove_callback(pmap_t pmap, struct pmap_inval_info *info,
2811 		     pv_entry_t pte_pv, pv_entry_t pt_pv, vm_offset_t va,
2812 		     pt_entry_t *ptep, void *arg __unused)
2813 {
2814 	pt_entry_t pte;
2815 
2816 	if (pte_pv) {
2817 		/*
2818 		 * This will also drop pt_pv's wire_count. Note that
2819 		 * terminal pages are not wired based on mmu presence.
2820 		 */
2821 		pmap_remove_pv_pte(pte_pv, pt_pv, info);
2822 		pmap_remove_pv_page(pte_pv);
2823 		pv_free(pte_pv);
2824 	} else {
2825 		/*
2826 		 * pt_pv's wire_count is still bumped by unmanaged pages
2827 		 * so we must decrement it manually.
2828 		 */
2829 		pmap_inval_interlock(info, pmap, va);
2830 		pte = pte_load_clear(ptep);
2831 		pmap_inval_deinterlock(info, pmap);
2832 		if (pte & PG_W)
2833 			atomic_add_long(&pmap->pm_stats.wired_count, -1);
2834 		atomic_add_long(&pmap->pm_stats.resident_count, -1);
2835 		if (pt_pv && vm_page_unwire_quick(pt_pv->pv_m))
2836 			panic("pmap_remove: insufficient wirecount");
2837 	}
2838 }
2839 
2840 /*
2841  * Removes this physical page from all physical maps in which it resides.
2842  * Reflects back modify bits to the pager.
2843  *
2844  * This routine may not be called from an interrupt.
2845  */
2846 static
2847 void
2848 pmap_remove_all(vm_page_t m)
2849 {
2850 	struct pmap_inval_info info;
2851 	pv_entry_t pv;
2852 
2853 	if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
2854 		return;
2855 
2856 	pmap_inval_init(&info);
2857 	vm_page_spin_lock(m);
2858 	while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
2859 		KKASSERT(pv->pv_m == m);
2860 		if (pv_hold_try(pv)) {
2861 			vm_page_spin_unlock(m);
2862 		} else {
2863 			vm_page_spin_unlock(m);
2864 			pv_lock(pv);
2865 			if (pv->pv_m != m) {
2866 				pv_put(pv);
2867 				vm_page_spin_lock(m);
2868 				continue;
2869 			}
2870 		}
2871 		/*
2872 		 * Holding no spinlocks, pv is locked.
2873 		 */
2874 		pmap_remove_pv_pte(pv, NULL, &info);
2875 		pmap_remove_pv_page(pv);
2876 		pv_free(pv);
2877 		vm_page_spin_lock(m);
2878 	}
2879 	KKASSERT((m->flags & (PG_MAPPED|PG_WRITEABLE)) == 0);
2880 	vm_page_spin_unlock(m);
2881 	pmap_inval_done(&info);
2882 }
2883 
2884 /*
2885  * pmap_protect:
2886  *
2887  *	Set the physical protection on the specified range of this map
2888  *	as requested.
2889  *
2890  *	This function may not be called from an interrupt if the map is
2891  *	not the kernel_pmap.
2892  */
2893 void
2894 pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
2895 {
2896 	/* JG review for NX */
2897 
2898 	if (pmap == NULL)
2899 		return;
2900 	if ((prot & VM_PROT_READ) == VM_PROT_NONE) {
2901 		pmap_remove(pmap, sva, eva);
2902 		return;
2903 	}
2904 	if (prot & VM_PROT_WRITE)
2905 		return;
2906 	pmap_scan(pmap, sva, eva, pmap_protect_callback, &prot);
2907 }
2908 
2909 static
2910 void
2911 pmap_protect_callback(pmap_t pmap, struct pmap_inval_info *info,
2912 		      pv_entry_t pte_pv, pv_entry_t pt_pv, vm_offset_t va,
2913 		      pt_entry_t *ptep, void *arg __unused)
2914 {
2915 	pt_entry_t pbits;
2916 	pt_entry_t cbits;
2917 	vm_page_t m;
2918 
2919 	/*
2920 	 * XXX non-optimal.
2921 	 */
2922 	pmap_inval_interlock(info, pmap, va);
2923 again:
2924 	pbits = *ptep;
2925 	cbits = pbits;
2926 	if (pte_pv) {
2927 		m = NULL;
2928 		if (pbits & PG_A) {
2929 			m = PHYS_TO_VM_PAGE(pbits & PG_FRAME);
2930 			KKASSERT(m == pte_pv->pv_m);
2931 			vm_page_flag_set(m, PG_REFERENCED);
2932 			cbits &= ~PG_A;
2933 		}
2934 		if (pbits & PG_M) {
2935 			if (pmap_track_modified(pte_pv->pv_pindex)) {
2936 				if (m == NULL)
2937 					m = PHYS_TO_VM_PAGE(pbits & PG_FRAME);
2938 				vm_page_dirty(m);
2939 				cbits &= ~PG_M;
2940 			}
2941 		}
2942 	}
2943 	cbits &= ~PG_RW;
2944 	if (pbits != cbits && !atomic_cmpset_long(ptep, pbits, cbits)) {
2945 		goto again;
2946 	}
2947 	pmap_inval_deinterlock(info, pmap);
2948 	if (pte_pv)
2949 		pv_put(pte_pv);
2950 }
2951 
2952 /*
2953  * Insert the vm_page (m) at the virtual address (va), replacing any prior
2954  * mapping at that address.  Set protection and wiring as requested.
2955  *
2956  * NOTE: This routine MUST insert the page into the pmap now, it cannot
2957  *	 lazy-evaluate.
2958  */
2959 void
2960 pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
2961 	   boolean_t wired)
2962 {
2963 	pmap_inval_info info;
2964 	pv_entry_t pt_pv;	/* page table */
2965 	pv_entry_t pte_pv;	/* page table entry */
2966 	pt_entry_t *ptep;
2967 	vm_paddr_t opa;
2968 	pt_entry_t origpte, newpte;
2969 	vm_paddr_t pa;
2970 
2971 	if (pmap == NULL)
2972 		return;
2973 	va = trunc_page(va);
2974 #ifdef PMAP_DIAGNOSTIC
2975 	if (va >= KvaEnd)
2976 		panic("pmap_enter: toobig");
2977 	if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS))
2978 		panic("pmap_enter: invalid to pmap_enter page table "
2979 		      "pages (va: 0x%lx)", va);
2980 #endif
2981 	if (va < UPT_MAX_ADDRESS && pmap == &kernel_pmap) {
2982 		kprintf("Warning: pmap_enter called on UVA with "
2983 			"kernel_pmap\n");
2984 #ifdef DDB
2985 		db_print_backtrace();
2986 #endif
2987 	}
2988 	if (va >= UPT_MAX_ADDRESS && pmap != &kernel_pmap) {
2989 		kprintf("Warning: pmap_enter called on KVA without"
2990 			"kernel_pmap\n");
2991 #ifdef DDB
2992 		db_print_backtrace();
2993 #endif
2994 	}
2995 
2996 	/*
2997 	 * Get locked PV entries for our new page table entry (pte_pv)
2998 	 * and for its parent page table (pt_pv).  We need the parent
2999 	 * so we can resolve the location of the ptep.
3000 	 *
3001 	 * Only hardware MMU actions can modify the ptep out from
3002 	 * under us.
3003 	 *
3004 	 * if (m) is fictitious or unmanaged we do not create a managing
3005 	 * pte_pv for it.  Any pre-existing page's management state must
3006 	 * match (avoiding code complexity).
3007 	 *
3008 	 * If the pmap is still being initialized we assume existing
3009 	 * page tables.
3010 	 *
3011 	 * Kernel mapppings do not track page table pages (i.e. pt_pv).
3012 	 * pmap_allocpte() checks the
3013 	 */
3014 	if (pmap_initialized == FALSE) {
3015 		pte_pv = NULL;
3016 		pt_pv = NULL;
3017 		ptep = vtopte(va);
3018 	} else if (m->flags & (PG_FICTITIOUS | PG_UNMANAGED)) {
3019 		pte_pv = NULL;
3020 		if (va >= VM_MAX_USER_ADDRESS) {
3021 			pt_pv = NULL;
3022 			ptep = vtopte(va);
3023 		} else {
3024 			pt_pv = pmap_allocpte(pmap, pmap_pt_pindex(va), NULL);
3025 			ptep = pv_pte_lookup(pt_pv, pmap_pte_index(va));
3026 		}
3027 		KKASSERT(*ptep == 0 || (*ptep & PG_MANAGED) == 0);
3028 	} else {
3029 		if (va >= VM_MAX_USER_ADDRESS) {
3030 			pt_pv = NULL;
3031 			pte_pv = pmap_allocpte(pmap, pmap_pte_pindex(va), NULL);
3032 			ptep = vtopte(va);
3033 		} else {
3034 			pte_pv = pmap_allocpte(pmap, pmap_pte_pindex(va),
3035 					       &pt_pv);
3036 			ptep = pv_pte_lookup(pt_pv, pmap_pte_index(va));
3037 		}
3038 		KKASSERT(*ptep == 0 || (*ptep & PG_MANAGED));
3039 	}
3040 
3041 	pa = VM_PAGE_TO_PHYS(m);
3042 	origpte = *ptep;
3043 	opa = origpte & PG_FRAME;
3044 
3045 	newpte = (pt_entry_t)(pa | pte_prot(pmap, prot) | PG_V | PG_A);
3046 	if (wired)
3047 		newpte |= PG_W;
3048 	if (va < VM_MAX_USER_ADDRESS)
3049 		newpte |= PG_U;
3050 	if (pte_pv)
3051 		newpte |= PG_MANAGED;
3052 	if (pmap == &kernel_pmap)
3053 		newpte |= pgeflag;
3054 
3055 	/*
3056 	 * It is possible for multiple faults to occur in threaded
3057 	 * environments, the existing pte might be correct.
3058 	 */
3059 	if (((origpte ^ newpte) & ~(pt_entry_t)(PG_M|PG_A)) == 0)
3060 		goto done;
3061 
3062 	if ((prot & VM_PROT_NOSYNC) == 0)
3063 		pmap_inval_init(&info);
3064 
3065 	/*
3066 	 * Ok, either the address changed or the protection or wiring
3067 	 * changed.
3068 	 *
3069 	 * Clear the current entry, interlocking the removal.  For managed
3070 	 * pte's this will also flush the modified state to the vm_page.
3071 	 * Atomic ops are mandatory in order to ensure that PG_M events are
3072 	 * not lost during any transition.
3073 	 */
3074 	if (opa) {
3075 		if (pte_pv) {
3076 			/*
3077 			 * pmap_remove_pv_pte() unwires pt_pv and assumes
3078 			 * we will free pte_pv, but since we are reusing
3079 			 * pte_pv we want to retain the wire count.
3080 			 *
3081 			 * pt_pv won't exist for a kernel page (managed or
3082 			 * otherwise).
3083 			 */
3084 			if (pt_pv)
3085 				vm_page_wire_quick(pt_pv->pv_m);
3086 			if (prot & VM_PROT_NOSYNC)
3087 				pmap_remove_pv_pte(pte_pv, pt_pv, NULL);
3088 			else
3089 				pmap_remove_pv_pte(pte_pv, pt_pv, &info);
3090 			if (pte_pv->pv_m)
3091 				pmap_remove_pv_page(pte_pv);
3092 		} else if (prot & VM_PROT_NOSYNC) {
3093 			/* leave wire count on PT page intact */
3094 			(void)pte_load_clear(ptep);
3095 			cpu_invlpg((void *)va);
3096 			atomic_add_long(&pmap->pm_stats.resident_count, -1);
3097 		} else {
3098 			/* leave wire count on PT page intact */
3099 			pmap_inval_interlock(&info, pmap, va);
3100 			(void)pte_load_clear(ptep);
3101 			pmap_inval_deinterlock(&info, pmap);
3102 			atomic_add_long(&pmap->pm_stats.resident_count, -1);
3103 		}
3104 		KKASSERT(*ptep == 0);
3105 	}
3106 
3107 	if (pte_pv) {
3108 		/*
3109 		 * Enter on the PV list if part of our managed memory.
3110 		 * Wiring of the PT page is already handled.
3111 		 */
3112 		KKASSERT(pte_pv->pv_m == NULL);
3113 		vm_page_spin_lock(m);
3114 		pte_pv->pv_m = m;
3115 		TAILQ_INSERT_TAIL(&m->md.pv_list, pte_pv, pv_list);
3116 		/*
3117 		if (m->object)
3118 			atomic_add_int(&m->object->agg_pv_list_count, 1);
3119 		*/
3120 		vm_page_flag_set(m, PG_MAPPED);
3121 		vm_page_spin_unlock(m);
3122 	} else if (pt_pv && opa == 0) {
3123 		/*
3124 		 * We have to adjust the wire count on the PT page ourselves
3125 		 * for unmanaged entries.  If opa was non-zero we retained
3126 		 * the existing wire count from the removal.
3127 		 */
3128 		vm_page_wire_quick(pt_pv->pv_m);
3129 	}
3130 
3131 	/*
3132 	 * Ok, for UVM (pt_pv != NULL) we don't need to interlock or
3133 	 * invalidate anything, the TLB won't have any stale entries to
3134 	 * remove.
3135 	 *
3136 	 * For KVM there appear to still be issues.  Theoretically we
3137 	 * should be able to scrap the interlocks entirely but we
3138 	 * get crashes.
3139 	 */
3140 	if ((prot & VM_PROT_NOSYNC) == 0 && pt_pv == NULL)
3141 		pmap_inval_interlock(&info, pmap, va);
3142 	*(volatile pt_entry_t *)ptep = newpte;
3143 
3144 	if ((prot & VM_PROT_NOSYNC) == 0 && pt_pv == NULL)
3145 		pmap_inval_deinterlock(&info, pmap);
3146 	else if (pt_pv == NULL)
3147 		cpu_invlpg((void *)va);
3148 
3149 	if (wired)
3150 		atomic_add_long(&pmap->pm_stats.wired_count, 1);
3151 	if (newpte & PG_RW)
3152 		vm_page_flag_set(m, PG_WRITEABLE);
3153 	if (pte_pv == NULL)
3154 		atomic_add_long(&pmap->pm_stats.resident_count, 1);
3155 
3156 	/*
3157 	 * Cleanup
3158 	 */
3159 	if ((prot & VM_PROT_NOSYNC) == 0 || pte_pv == NULL)
3160 		pmap_inval_done(&info);
3161 done:
3162 	KKASSERT((newpte & PG_MANAGED) == 0 || (m->flags & PG_MAPPED));
3163 
3164 	/*
3165 	 * Cleanup the pv entry, allowing other accessors.
3166 	 */
3167 	if (pte_pv)
3168 		pv_put(pte_pv);
3169 	if (pt_pv)
3170 		pv_put(pt_pv);
3171 }
3172 
3173 /*
3174  * This code works like pmap_enter() but assumes VM_PROT_READ and not-wired.
3175  * This code also assumes that the pmap has no pre-existing entry for this
3176  * VA.
3177  *
3178  * This code currently may only be used on user pmaps, not kernel_pmap.
3179  */
3180 void
3181 pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m)
3182 {
3183 	pmap_enter(pmap, va, m, VM_PROT_READ, FALSE);
3184 }
3185 
3186 /*
3187  * Make a temporary mapping for a physical address.  This is only intended
3188  * to be used for panic dumps.
3189  *
3190  * The caller is responsible for calling smp_invltlb().
3191  */
3192 void *
3193 pmap_kenter_temporary(vm_paddr_t pa, long i)
3194 {
3195 	pmap_kenter_quick((vm_offset_t)crashdumpmap + (i * PAGE_SIZE), pa);
3196 	return ((void *)crashdumpmap);
3197 }
3198 
3199 #define MAX_INIT_PT (96)
3200 
3201 /*
3202  * This routine preloads the ptes for a given object into the specified pmap.
3203  * This eliminates the blast of soft faults on process startup and
3204  * immediately after an mmap.
3205  */
3206 static int pmap_object_init_pt_callback(vm_page_t p, void *data);
3207 
3208 void
3209 pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, vm_prot_t prot,
3210 		    vm_object_t object, vm_pindex_t pindex,
3211 		    vm_size_t size, int limit)
3212 {
3213 	struct rb_vm_page_scan_info info;
3214 	struct lwp *lp;
3215 	vm_size_t psize;
3216 
3217 	/*
3218 	 * We can't preinit if read access isn't set or there is no pmap
3219 	 * or object.
3220 	 */
3221 	if ((prot & VM_PROT_READ) == 0 || pmap == NULL || object == NULL)
3222 		return;
3223 
3224 	/*
3225 	 * We can't preinit if the pmap is not the current pmap
3226 	 */
3227 	lp = curthread->td_lwp;
3228 	if (lp == NULL || pmap != vmspace_pmap(lp->lwp_vmspace))
3229 		return;
3230 
3231 	psize = x86_64_btop(size);
3232 
3233 	if ((object->type != OBJT_VNODE) ||
3234 		((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) &&
3235 			(object->resident_page_count > MAX_INIT_PT))) {
3236 		return;
3237 	}
3238 
3239 	if (pindex + psize > object->size) {
3240 		if (object->size < pindex)
3241 			return;
3242 		psize = object->size - pindex;
3243 	}
3244 
3245 	if (psize == 0)
3246 		return;
3247 
3248 	/*
3249 	 * Use a red-black scan to traverse the requested range and load
3250 	 * any valid pages found into the pmap.
3251 	 *
3252 	 * We cannot safely scan the object's memq without holding the
3253 	 * object token.
3254 	 */
3255 	info.start_pindex = pindex;
3256 	info.end_pindex = pindex + psize - 1;
3257 	info.limit = limit;
3258 	info.mpte = NULL;
3259 	info.addr = addr;
3260 	info.pmap = pmap;
3261 
3262 	vm_object_hold_shared(object);
3263 	vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp,
3264 				pmap_object_init_pt_callback, &info);
3265 	vm_object_drop(object);
3266 }
3267 
3268 static
3269 int
3270 pmap_object_init_pt_callback(vm_page_t p, void *data)
3271 {
3272 	struct rb_vm_page_scan_info *info = data;
3273 	vm_pindex_t rel_index;
3274 
3275 	/*
3276 	 * don't allow an madvise to blow away our really
3277 	 * free pages allocating pv entries.
3278 	 */
3279 	if ((info->limit & MAP_PREFAULT_MADVISE) &&
3280 		vmstats.v_free_count < vmstats.v_free_reserved) {
3281 		    return(-1);
3282 	}
3283 
3284 	/*
3285 	 * Ignore list markers and ignore pages we cannot instantly
3286 	 * busy (while holding the object token).
3287 	 */
3288 	if (p->flags & PG_MARKER)
3289 		return 0;
3290 	if (vm_page_busy_try(p, TRUE))
3291 		return 0;
3292 	if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) &&
3293 	    (p->flags & PG_FICTITIOUS) == 0) {
3294 		if ((p->queue - p->pc) == PQ_CACHE)
3295 			vm_page_deactivate(p);
3296 		rel_index = p->pindex - info->start_pindex;
3297 		pmap_enter_quick(info->pmap,
3298 				 info->addr + x86_64_ptob(rel_index), p);
3299 	}
3300 	vm_page_wakeup(p);
3301 	lwkt_yield();
3302 	return(0);
3303 }
3304 
3305 /*
3306  * Return TRUE if the pmap is in shape to trivially pre-fault the specified
3307  * address.
3308  *
3309  * Returns FALSE if it would be non-trivial or if a pte is already loaded
3310  * into the slot.
3311  *
3312  * XXX This is safe only because page table pages are not freed.
3313  */
3314 int
3315 pmap_prefault_ok(pmap_t pmap, vm_offset_t addr)
3316 {
3317 	pt_entry_t *pte;
3318 
3319 	/*spin_lock(&pmap->pm_spin);*/
3320 	if ((pte = pmap_pte(pmap, addr)) != NULL) {
3321 		if (*pte & PG_V) {
3322 			/*spin_unlock(&pmap->pm_spin);*/
3323 			return FALSE;
3324 		}
3325 	}
3326 	/*spin_unlock(&pmap->pm_spin);*/
3327 	return TRUE;
3328 }
3329 
3330 /*
3331  * Change the wiring attribute for a pmap/va pair.  The mapping must already
3332  * exist in the pmap.  The mapping may or may not be managed.
3333  */
3334 void
3335 pmap_change_wiring(pmap_t pmap, vm_offset_t va, boolean_t wired)
3336 {
3337 	pt_entry_t *ptep;
3338 	pv_entry_t pv;
3339 
3340 	if (pmap == NULL)
3341 		return;
3342 	lwkt_gettoken(&pmap->pm_token);
3343 	pv = pmap_allocpte(pmap, pmap_pt_pindex(va), NULL);
3344 	ptep = pv_pte_lookup(pv, pmap_pte_index(va));
3345 
3346 	if (wired && !pmap_pte_w(ptep))
3347 		atomic_add_long(&pmap->pm_stats.wired_count, 1);
3348 	else if (!wired && pmap_pte_w(ptep))
3349 		atomic_add_long(&pmap->pm_stats.wired_count, -1);
3350 
3351 	/*
3352 	 * Wiring is not a hardware characteristic so there is no need to
3353 	 * invalidate TLB.  However, in an SMP environment we must use
3354 	 * a locked bus cycle to update the pte (if we are not using
3355 	 * the pmap_inval_*() API that is)... it's ok to do this for simple
3356 	 * wiring changes.
3357 	 */
3358 #ifdef SMP
3359 	if (wired)
3360 		atomic_set_long(ptep, PG_W);
3361 	else
3362 		atomic_clear_long(ptep, PG_W);
3363 #else
3364 	if (wired)
3365 		atomic_set_long_nonlocked(ptep, PG_W);
3366 	else
3367 		atomic_clear_long_nonlocked(ptep, PG_W);
3368 #endif
3369 	pv_put(pv);
3370 	lwkt_reltoken(&pmap->pm_token);
3371 }
3372 
3373 
3374 
3375 /*
3376  * Copy the range specified by src_addr/len from the source map to
3377  * the range dst_addr/len in the destination map.
3378  *
3379  * This routine is only advisory and need not do anything.
3380  */
3381 void
3382 pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr,
3383 	  vm_size_t len, vm_offset_t src_addr)
3384 {
3385 }
3386 
3387 /*
3388  * pmap_zero_page:
3389  *
3390  *	Zero the specified physical page.
3391  *
3392  *	This function may be called from an interrupt and no locking is
3393  *	required.
3394  */
3395 void
3396 pmap_zero_page(vm_paddr_t phys)
3397 {
3398 	vm_offset_t va = PHYS_TO_DMAP(phys);
3399 
3400 	pagezero((void *)va);
3401 }
3402 
3403 /*
3404  * pmap_page_assertzero:
3405  *
3406  *	Assert that a page is empty, panic if it isn't.
3407  */
3408 void
3409 pmap_page_assertzero(vm_paddr_t phys)
3410 {
3411 	vm_offset_t va = PHYS_TO_DMAP(phys);
3412 	size_t i;
3413 
3414 	for (i = 0; i < PAGE_SIZE; i += sizeof(long)) {
3415 		if (*(long *)((char *)va + i) != 0) {
3416 			panic("pmap_page_assertzero() @ %p not zero!",
3417 			      (void *)(intptr_t)va);
3418 		}
3419 	}
3420 }
3421 
3422 /*
3423  * pmap_zero_page:
3424  *
3425  *	Zero part of a physical page by mapping it into memory and clearing
3426  *	its contents with bzero.
3427  *
3428  *	off and size may not cover an area beyond a single hardware page.
3429  */
3430 void
3431 pmap_zero_page_area(vm_paddr_t phys, int off, int size)
3432 {
3433 	vm_offset_t virt = PHYS_TO_DMAP(phys);
3434 
3435 	bzero((char *)virt + off, size);
3436 }
3437 
3438 /*
3439  * pmap_copy_page:
3440  *
3441  *	Copy the physical page from the source PA to the target PA.
3442  *	This function may be called from an interrupt.  No locking
3443  *	is required.
3444  */
3445 void
3446 pmap_copy_page(vm_paddr_t src, vm_paddr_t dst)
3447 {
3448 	vm_offset_t src_virt, dst_virt;
3449 
3450 	src_virt = PHYS_TO_DMAP(src);
3451 	dst_virt = PHYS_TO_DMAP(dst);
3452 	bcopy((void *)src_virt, (void *)dst_virt, PAGE_SIZE);
3453 }
3454 
3455 /*
3456  * pmap_copy_page_frag:
3457  *
3458  *	Copy the physical page from the source PA to the target PA.
3459  *	This function may be called from an interrupt.  No locking
3460  *	is required.
3461  */
3462 void
3463 pmap_copy_page_frag(vm_paddr_t src, vm_paddr_t dst, size_t bytes)
3464 {
3465 	vm_offset_t src_virt, dst_virt;
3466 
3467 	src_virt = PHYS_TO_DMAP(src);
3468 	dst_virt = PHYS_TO_DMAP(dst);
3469 
3470 	bcopy((char *)src_virt + (src & PAGE_MASK),
3471 	      (char *)dst_virt + (dst & PAGE_MASK),
3472 	      bytes);
3473 }
3474 
3475 /*
3476  * Returns true if the pmap's pv is one of the first 16 pvs linked to from
3477  * this page.  This count may be changed upwards or downwards in the future;
3478  * it is only necessary that true be returned for a small subset of pmaps
3479  * for proper page aging.
3480  */
3481 boolean_t
3482 pmap_page_exists_quick(pmap_t pmap, vm_page_t m)
3483 {
3484 	pv_entry_t pv;
3485 	int loops = 0;
3486 
3487 	if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
3488 		return FALSE;
3489 
3490 	vm_page_spin_lock(m);
3491 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
3492 		if (pv->pv_pmap == pmap) {
3493 			vm_page_spin_unlock(m);
3494 			return TRUE;
3495 		}
3496 		loops++;
3497 		if (loops >= 16)
3498 			break;
3499 	}
3500 	vm_page_spin_unlock(m);
3501 	return (FALSE);
3502 }
3503 
3504 /*
3505  * Remove all pages from specified address space this aids process exit
3506  * speeds.  Also, this code may be special cased for the current process
3507  * only.
3508  */
3509 void
3510 pmap_remove_pages(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
3511 {
3512 	pmap_remove(pmap, sva, eva);
3513 }
3514 
3515 /*
3516  * pmap_testbit tests bits in pte's note that the testbit/clearbit
3517  * routines are inline, and a lot of things compile-time evaluate.
3518  */
3519 static
3520 boolean_t
3521 pmap_testbit(vm_page_t m, int bit)
3522 {
3523 	pv_entry_t pv;
3524 	pt_entry_t *pte;
3525 
3526 	if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
3527 		return FALSE;
3528 
3529 	if (TAILQ_FIRST(&m->md.pv_list) == NULL)
3530 		return FALSE;
3531 	vm_page_spin_lock(m);
3532 	if (TAILQ_FIRST(&m->md.pv_list) == NULL) {
3533 		vm_page_spin_unlock(m);
3534 		return FALSE;
3535 	}
3536 
3537 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
3538 		/*
3539 		 * if the bit being tested is the modified bit, then
3540 		 * mark clean_map and ptes as never
3541 		 * modified.
3542 		 */
3543 		if (bit & (PG_A|PG_M)) {
3544 			if (!pmap_track_modified(pv->pv_pindex))
3545 				continue;
3546 		}
3547 
3548 #if defined(PMAP_DIAGNOSTIC)
3549 		if (pv->pv_pmap == NULL) {
3550 			kprintf("Null pmap (tb) at pindex: %"PRIu64"\n",
3551 			    pv->pv_pindex);
3552 			continue;
3553 		}
3554 #endif
3555 		pte = pmap_pte_quick(pv->pv_pmap, pv->pv_pindex << PAGE_SHIFT);
3556 		if (*pte & bit) {
3557 			vm_page_spin_unlock(m);
3558 			return TRUE;
3559 		}
3560 	}
3561 	vm_page_spin_unlock(m);
3562 	return (FALSE);
3563 }
3564 
3565 /*
3566  * This routine is used to modify bits in ptes.  Only one bit should be
3567  * specified.  PG_RW requires special handling.
3568  *
3569  * Caller must NOT hold any spin locks
3570  */
3571 static __inline
3572 void
3573 pmap_clearbit(vm_page_t m, int bit)
3574 {
3575 	struct pmap_inval_info info;
3576 	pv_entry_t pv;
3577 	pt_entry_t *pte;
3578 	pt_entry_t pbits;
3579 	pmap_t save_pmap;
3580 
3581 	if (bit == PG_RW)
3582 		vm_page_flag_clear(m, PG_WRITEABLE);
3583 	if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) {
3584 		return;
3585 	}
3586 
3587 	/*
3588 	 * PG_M or PG_A case
3589 	 *
3590 	 * Loop over all current mappings setting/clearing as appropos If
3591 	 * setting RO do we need to clear the VAC?
3592 	 *
3593 	 * NOTE: When clearing PG_M we could also (not implemented) drop
3594 	 *	 through to the PG_RW code and clear PG_RW too, forcing
3595 	 *	 a fault on write to redetect PG_M for virtual kernels, but
3596 	 *	 it isn't necessary since virtual kernels invalidate the
3597 	 *	 pte when they clear the VPTE_M bit in their virtual page
3598 	 *	 tables.
3599 	 *
3600 	 * NOTE: Does not re-dirty the page when clearing only PG_M.
3601 	 */
3602 	if ((bit & PG_RW) == 0) {
3603 		vm_page_spin_lock(m);
3604 		TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
3605 	#if defined(PMAP_DIAGNOSTIC)
3606 			if (pv->pv_pmap == NULL) {
3607 				kprintf("Null pmap (cb) at pindex: %"PRIu64"\n",
3608 				    pv->pv_pindex);
3609 				continue;
3610 			}
3611 	#endif
3612 			pte = pmap_pte_quick(pv->pv_pmap,
3613 					     pv->pv_pindex << PAGE_SHIFT);
3614 			pbits = *pte;
3615 			if (pbits & bit)
3616 				atomic_clear_long(pte, bit);
3617 		}
3618 		vm_page_spin_unlock(m);
3619 		return;
3620 	}
3621 
3622 	/*
3623 	 * Clear PG_RW.  Also clears PG_M and marks the page dirty if PG_M
3624 	 * was set.
3625 	 */
3626 	pmap_inval_init(&info);
3627 
3628 restart:
3629 	vm_page_spin_lock(m);
3630 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
3631 		/*
3632 		 * don't write protect pager mappings
3633 		 */
3634 		if (!pmap_track_modified(pv->pv_pindex))
3635 			continue;
3636 
3637 #if defined(PMAP_DIAGNOSTIC)
3638 		if (pv->pv_pmap == NULL) {
3639 			kprintf("Null pmap (cb) at pindex: %"PRIu64"\n",
3640 			    pv->pv_pindex);
3641 			continue;
3642 		}
3643 #endif
3644 		/*
3645 		 * Skip pages which do not have PG_RW set.
3646 		 */
3647 		pte = pmap_pte_quick(pv->pv_pmap, pv->pv_pindex << PAGE_SHIFT);
3648 		if ((*pte & PG_RW) == 0)
3649 			continue;
3650 
3651 		/*
3652 		 * Lock the PV
3653 		 */
3654 		if (pv_hold_try(pv) == 0) {
3655 			vm_page_spin_unlock(m);
3656 			pv_lock(pv);	/* held, now do a blocking lock */
3657 			pv_put(pv);	/* and release */
3658 			goto restart;	/* anything could have happened */
3659 		}
3660 
3661 		save_pmap = pv->pv_pmap;
3662 		vm_page_spin_unlock(m);
3663 		pmap_inval_interlock(&info, save_pmap,
3664 				     (vm_offset_t)pv->pv_pindex << PAGE_SHIFT);
3665 		KKASSERT(pv->pv_pmap == save_pmap);
3666 		for (;;) {
3667 			pbits = *pte;
3668 			cpu_ccfence();
3669 			if (atomic_cmpset_long(pte, pbits,
3670 					       pbits & ~(PG_RW|PG_M))) {
3671 				break;
3672 			}
3673 		}
3674 		pmap_inval_deinterlock(&info, save_pmap);
3675 		vm_page_spin_lock(m);
3676 
3677 		/*
3678 		 * If PG_M was found to be set while we were clearing PG_RW
3679 		 * we also clear PG_M (done above) and mark the page dirty.
3680 		 * Callers expect this behavior.
3681 		 */
3682 		if (pbits & PG_M)
3683 			vm_page_dirty(m);
3684 		pv_put(pv);
3685 	}
3686 	vm_page_spin_unlock(m);
3687 	pmap_inval_done(&info);
3688 }
3689 
3690 /*
3691  * Lower the permission for all mappings to a given page.
3692  *
3693  * Page must be busied by caller.
3694  */
3695 void
3696 pmap_page_protect(vm_page_t m, vm_prot_t prot)
3697 {
3698 	/* JG NX support? */
3699 	if ((prot & VM_PROT_WRITE) == 0) {
3700 		if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) {
3701 			/*
3702 			 * NOTE: pmap_clearbit(.. PG_RW) also clears
3703 			 *	 the PG_WRITEABLE flag in (m).
3704 			 */
3705 			pmap_clearbit(m, PG_RW);
3706 		} else {
3707 			pmap_remove_all(m);
3708 		}
3709 	}
3710 }
3711 
3712 vm_paddr_t
3713 pmap_phys_address(vm_pindex_t ppn)
3714 {
3715 	return (x86_64_ptob(ppn));
3716 }
3717 
3718 /*
3719  * Return a count of reference bits for a page, clearing those bits.
3720  * It is not necessary for every reference bit to be cleared, but it
3721  * is necessary that 0 only be returned when there are truly no
3722  * reference bits set.
3723  *
3724  * XXX: The exact number of bits to check and clear is a matter that
3725  * should be tested and standardized at some point in the future for
3726  * optimal aging of shared pages.
3727  *
3728  * This routine may not block.
3729  */
3730 int
3731 pmap_ts_referenced(vm_page_t m)
3732 {
3733 	pv_entry_t pv;
3734 	pt_entry_t *pte;
3735 	int rtval = 0;
3736 
3737 	if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
3738 		return (rtval);
3739 
3740 	vm_page_spin_lock(m);
3741 	TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
3742 		if (!pmap_track_modified(pv->pv_pindex))
3743 			continue;
3744 		pte = pmap_pte_quick(pv->pv_pmap, pv->pv_pindex << PAGE_SHIFT);
3745 		if (pte && (*pte & PG_A)) {
3746 #ifdef SMP
3747 			atomic_clear_long(pte, PG_A);
3748 #else
3749 			atomic_clear_long_nonlocked(pte, PG_A);
3750 #endif
3751 			rtval++;
3752 			if (rtval > 4)
3753 				break;
3754 		}
3755 	}
3756 	vm_page_spin_unlock(m);
3757 	return (rtval);
3758 }
3759 
3760 /*
3761  *	pmap_is_modified:
3762  *
3763  *	Return whether or not the specified physical page was modified
3764  *	in any physical maps.
3765  */
3766 boolean_t
3767 pmap_is_modified(vm_page_t m)
3768 {
3769 	boolean_t res;
3770 
3771 	res = pmap_testbit(m, PG_M);
3772 	return (res);
3773 }
3774 
3775 /*
3776  *	Clear the modify bits on the specified physical page.
3777  */
3778 void
3779 pmap_clear_modify(vm_page_t m)
3780 {
3781 	pmap_clearbit(m, PG_M);
3782 }
3783 
3784 /*
3785  *	pmap_clear_reference:
3786  *
3787  *	Clear the reference bit on the specified physical page.
3788  */
3789 void
3790 pmap_clear_reference(vm_page_t m)
3791 {
3792 	pmap_clearbit(m, PG_A);
3793 }
3794 
3795 /*
3796  * Miscellaneous support routines follow
3797  */
3798 
3799 static
3800 void
3801 i386_protection_init(void)
3802 {
3803 	int *kp, prot;
3804 
3805 	/* JG NX support may go here; No VM_PROT_EXECUTE ==> set NX bit  */
3806 	kp = protection_codes;
3807 	for (prot = 0; prot < 8; prot++) {
3808 		switch (prot) {
3809 		case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE:
3810 			/*
3811 			 * Read access is also 0. There isn't any execute bit,
3812 			 * so just make it readable.
3813 			 */
3814 		case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE:
3815 		case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE:
3816 		case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE:
3817 			*kp++ = 0;
3818 			break;
3819 		case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE:
3820 		case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE:
3821 		case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE:
3822 		case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE:
3823 			*kp++ = PG_RW;
3824 			break;
3825 		}
3826 	}
3827 }
3828 
3829 /*
3830  * Map a set of physical memory pages into the kernel virtual
3831  * address space. Return a pointer to where it is mapped. This
3832  * routine is intended to be used for mapping device memory,
3833  * NOT real memory.
3834  *
3835  * NOTE: we can't use pgeflag unless we invalidate the pages one at
3836  * a time.
3837  */
3838 void *
3839 pmap_mapdev(vm_paddr_t pa, vm_size_t size)
3840 {
3841 	vm_offset_t va, tmpva, offset;
3842 	pt_entry_t *pte;
3843 
3844 	offset = pa & PAGE_MASK;
3845 	size = roundup(offset + size, PAGE_SIZE);
3846 
3847 	va = kmem_alloc_nofault(&kernel_map, size, PAGE_SIZE);
3848 	if (va == 0)
3849 		panic("pmap_mapdev: Couldn't alloc kernel virtual memory");
3850 
3851 	pa = pa & ~PAGE_MASK;
3852 	for (tmpva = va; size > 0;) {
3853 		pte = vtopte(tmpva);
3854 		*pte = pa | PG_RW | PG_V; /* | pgeflag; */
3855 		size -= PAGE_SIZE;
3856 		tmpva += PAGE_SIZE;
3857 		pa += PAGE_SIZE;
3858 	}
3859 	cpu_invltlb();
3860 	smp_invltlb();
3861 
3862 	return ((void *)(va + offset));
3863 }
3864 
3865 void *
3866 pmap_mapdev_uncacheable(vm_paddr_t pa, vm_size_t size)
3867 {
3868 	vm_offset_t va, tmpva, offset;
3869 	pt_entry_t *pte;
3870 
3871 	offset = pa & PAGE_MASK;
3872 	size = roundup(offset + size, PAGE_SIZE);
3873 
3874 	va = kmem_alloc_nofault(&kernel_map, size, PAGE_SIZE);
3875 	if (va == 0)
3876 		panic("pmap_mapdev: Couldn't alloc kernel virtual memory");
3877 
3878 	pa = pa & ~PAGE_MASK;
3879 	for (tmpva = va; size > 0;) {
3880 		pte = vtopte(tmpva);
3881 		*pte = pa | PG_RW | PG_V | PG_N; /* | pgeflag; */
3882 		size -= PAGE_SIZE;
3883 		tmpva += PAGE_SIZE;
3884 		pa += PAGE_SIZE;
3885 	}
3886 	cpu_invltlb();
3887 	smp_invltlb();
3888 
3889 	return ((void *)(va + offset));
3890 }
3891 
3892 void
3893 pmap_unmapdev(vm_offset_t va, vm_size_t size)
3894 {
3895 	vm_offset_t base, offset;
3896 
3897 	base = va & ~PAGE_MASK;
3898 	offset = va & PAGE_MASK;
3899 	size = roundup(offset + size, PAGE_SIZE);
3900 	pmap_qremove(va, size >> PAGE_SHIFT);
3901 	kmem_free(&kernel_map, base, size);
3902 }
3903 
3904 /*
3905  * perform the pmap work for mincore
3906  */
3907 int
3908 pmap_mincore(pmap_t pmap, vm_offset_t addr)
3909 {
3910 	pt_entry_t *ptep, pte;
3911 	vm_page_t m;
3912 	int val = 0;
3913 
3914 	lwkt_gettoken(&pmap->pm_token);
3915 	ptep = pmap_pte(pmap, addr);
3916 
3917 	if (ptep && (pte = *ptep) != 0) {
3918 		vm_offset_t pa;
3919 
3920 		val = MINCORE_INCORE;
3921 		if ((pte & PG_MANAGED) == 0)
3922 			goto done;
3923 
3924 		pa = pte & PG_FRAME;
3925 
3926 		m = PHYS_TO_VM_PAGE(pa);
3927 
3928 		/*
3929 		 * Modified by us
3930 		 */
3931 		if (pte & PG_M)
3932 			val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER;
3933 		/*
3934 		 * Modified by someone
3935 		 */
3936 		else if (m->dirty || pmap_is_modified(m))
3937 			val |= MINCORE_MODIFIED_OTHER;
3938 		/*
3939 		 * Referenced by us
3940 		 */
3941 		if (pte & PG_A)
3942 			val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER;
3943 
3944 		/*
3945 		 * Referenced by someone
3946 		 */
3947 		else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) {
3948 			val |= MINCORE_REFERENCED_OTHER;
3949 			vm_page_flag_set(m, PG_REFERENCED);
3950 		}
3951 	}
3952 done:
3953 	lwkt_reltoken(&pmap->pm_token);
3954 
3955 	return val;
3956 }
3957 
3958 /*
3959  * Replace p->p_vmspace with a new one.  If adjrefs is non-zero the new
3960  * vmspace will be ref'd and the old one will be deref'd.
3961  *
3962  * The vmspace for all lwps associated with the process will be adjusted
3963  * and cr3 will be reloaded if any lwp is the current lwp.
3964  *
3965  * The process must hold the vmspace->vm_map.token for oldvm and newvm
3966  */
3967 void
3968 pmap_replacevm(struct proc *p, struct vmspace *newvm, int adjrefs)
3969 {
3970 	struct vmspace *oldvm;
3971 	struct lwp *lp;
3972 
3973 	oldvm = p->p_vmspace;
3974 	if (oldvm != newvm) {
3975 		if (adjrefs)
3976 			sysref_get(&newvm->vm_sysref);
3977 		p->p_vmspace = newvm;
3978 		KKASSERT(p->p_nthreads == 1);
3979 		lp = RB_ROOT(&p->p_lwp_tree);
3980 		pmap_setlwpvm(lp, newvm);
3981 		if (adjrefs)
3982 			sysref_put(&oldvm->vm_sysref);
3983 	}
3984 }
3985 
3986 /*
3987  * Set the vmspace for a LWP.  The vmspace is almost universally set the
3988  * same as the process vmspace, but virtual kernels need to swap out contexts
3989  * on a per-lwp basis.
3990  *
3991  * Caller does not necessarily hold any vmspace tokens.  Caller must control
3992  * the lwp (typically be in the context of the lwp).  We use a critical
3993  * section to protect against statclock and hardclock (statistics collection).
3994  */
3995 void
3996 pmap_setlwpvm(struct lwp *lp, struct vmspace *newvm)
3997 {
3998 	struct vmspace *oldvm;
3999 	struct pmap *pmap;
4000 
4001 	oldvm = lp->lwp_vmspace;
4002 
4003 	if (oldvm != newvm) {
4004 		crit_enter();
4005 		lp->lwp_vmspace = newvm;
4006 		if (curthread->td_lwp == lp) {
4007 			pmap = vmspace_pmap(newvm);
4008 #if defined(SMP)
4009 			atomic_set_cpumask(&pmap->pm_active, mycpu->gd_cpumask);
4010 			if (pmap->pm_active & CPUMASK_LOCK)
4011 				pmap_interlock_wait(newvm);
4012 #else
4013 			pmap->pm_active |= 1;
4014 #endif
4015 #if defined(SWTCH_OPTIM_STATS)
4016 			tlb_flush_count++;
4017 #endif
4018 			curthread->td_pcb->pcb_cr3 = vtophys(pmap->pm_pml4);
4019 			curthread->td_pcb->pcb_cr3 |= PG_RW | PG_U | PG_V;
4020 			load_cr3(curthread->td_pcb->pcb_cr3);
4021 			pmap = vmspace_pmap(oldvm);
4022 #if defined(SMP)
4023 			atomic_clear_cpumask(&pmap->pm_active, mycpu->gd_cpumask);
4024 #else
4025 			pmap->pm_active &= ~(cpumask_t)1;
4026 #endif
4027 		}
4028 		crit_exit();
4029 	}
4030 }
4031 
4032 #ifdef SMP
4033 
4034 /*
4035  * Called when switching to a locked pmap, used to interlock against pmaps
4036  * undergoing modifications to prevent us from activating the MMU for the
4037  * target pmap until all such modifications have completed.  We have to do
4038  * this because the thread making the modifications has already set up its
4039  * SMP synchronization mask.
4040  *
4041  * This function cannot sleep!
4042  *
4043  * No requirements.
4044  */
4045 void
4046 pmap_interlock_wait(struct vmspace *vm)
4047 {
4048 	struct pmap *pmap = &vm->vm_pmap;
4049 
4050 	if (pmap->pm_active & CPUMASK_LOCK) {
4051 		crit_enter();
4052 		KKASSERT(curthread->td_critcount >= 2);
4053 		DEBUG_PUSH_INFO("pmap_interlock_wait");
4054 		while (pmap->pm_active & CPUMASK_LOCK) {
4055 			cpu_ccfence();
4056 			lwkt_process_ipiq();
4057 		}
4058 		DEBUG_POP_INFO();
4059 		crit_exit();
4060 	}
4061 }
4062 
4063 #endif
4064 
4065 vm_offset_t
4066 pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size)
4067 {
4068 
4069 	if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) {
4070 		return addr;
4071 	}
4072 
4073 	addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1);
4074 	return addr;
4075 }
4076 
4077 /*
4078  * Used by kmalloc/kfree, page already exists at va
4079  */
4080 vm_page_t
4081 pmap_kvtom(vm_offset_t va)
4082 {
4083 	return(PHYS_TO_VM_PAGE(*vtopte(va) & PG_FRAME));
4084 }
4085