Merge branch 'vendor/LDNS'
[dragonfly.git] / sys / platform / pc64 / x86_64 / pmap.c
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) 2011-2012 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/kernel.h>
56 #include <sys/proc.h>
57 #include <sys/msgbuf.h>
58 #include <sys/vmmeter.h>
59 #include <sys/mman.h>
60 #include <sys/systm.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(pmap, pte)           ((*(pd_entry_t *)pte & pmap->pmap_bits[PG_V_IDX]) != 0)
141 #define pmap_pte_w(pmap, pte)           ((*(pt_entry_t *)pte & pmap->pmap_bits[PG_W_IDX]) != 0)
142 #define pmap_pte_m(pmap, pte)           ((*(pt_entry_t *)pte & pmap->pmap_bits[PG_M_IDX]) != 0)
143 #define pmap_pte_u(pmap, pte)           ((*(pt_entry_t *)pte & pmap->pmap_bits[PG_U_IDX]) != 0)
144 #define pmap_pte_v(pmap, pte)           ((*(pt_entry_t *)pte & pmap->pmap_bits[PG_V_IDX]) != 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         (m->protection_codes[p & (VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE)])
152 static int protection_codes[PROTECTION_CODES_SIZE];
153
154 struct pmap kernel_pmap;
155 static TAILQ_HEAD(,pmap)        pmap_list = TAILQ_HEAD_INITIALIZER(pmap_list);
156
157 MALLOC_DEFINE(M_OBJPMAP, "objpmap", "pmaps associated with VM objects");
158
159 vm_paddr_t avail_start;         /* PA of first available physical page */
160 vm_paddr_t avail_end;           /* PA of last available physical page */
161 vm_offset_t virtual2_start;     /* cutout free area prior to kernel start */
162 vm_offset_t virtual2_end;
163 vm_offset_t virtual_start;      /* VA of first avail page (after kernel bss) */
164 vm_offset_t virtual_end;        /* VA of last avail page (end of kernel AS) */
165 vm_offset_t KvaStart;           /* VA start of KVA space */
166 vm_offset_t KvaEnd;             /* VA end of KVA space (non-inclusive) */
167 vm_offset_t KvaSize;            /* max size of kernel virtual address space */
168 static boolean_t pmap_initialized = FALSE;      /* Has pmap_init completed? */
169 //static int pgeflag;           /* PG_G or-in */
170 //static int pseflag;           /* PG_PS or-in */
171 uint64_t PatMsr;
172
173 static int ndmpdp;
174 static vm_paddr_t dmaplimit;
175 static int nkpt;
176 vm_offset_t kernel_vm_end = VM_MIN_KERNEL_ADDRESS;
177
178 static pt_entry_t pat_pte_index[PAT_INDEX_SIZE];        /* PAT -> PG_ bits */
179 /*static pt_entry_t pat_pde_index[PAT_INDEX_SIZE];*/    /* PAT -> PG_ bits */
180
181 static uint64_t KPTbase;
182 static uint64_t KPTphys;
183 static uint64_t KPDphys;        /* phys addr of kernel level 2 */
184 static uint64_t KPDbase;        /* phys addr of kernel level 2 @ KERNBASE */
185 uint64_t KPDPphys;      /* phys addr of kernel level 3 */
186 uint64_t KPML4phys;     /* phys addr of kernel level 4 */
187
188 static uint64_t DMPDphys;       /* phys addr of direct mapped level 2 */
189 static uint64_t DMPDPphys;      /* phys addr of direct mapped level 3 */
190
191 /*
192  * Data for the pv entry allocation mechanism
193  */
194 static vm_zone_t pvzone;
195 static struct vm_zone pvzone_store;
196 static struct vm_object pvzone_obj;
197 static int pv_entry_max=0, pv_entry_high_water=0;
198 static int pmap_pagedaemon_waken = 0;
199 static struct pv_entry *pvinit;
200
201 /*
202  * All those kernel PT submaps that BSD is so fond of
203  */
204 pt_entry_t *CMAP1 = NULL, *ptmmap;
205 caddr_t CADDR1 = NULL, ptvmmap = NULL;
206 static pt_entry_t *msgbufmap;
207 struct msgbuf *msgbufp=NULL;
208
209 /*
210  * PMAP default PG_* bits. Needed to be able to add
211  * EPT/NPT pagetable pmap_bits for the VMM module
212  */
213 uint64_t pmap_bits_default[] = {
214                 REGULAR_PMAP,                                   /* TYPE_IDX             0 */
215                 X86_PG_V,                                       /* PG_V_IDX             1 */
216                 X86_PG_RW,                                      /* PG_RW_IDX            2 */
217                 X86_PG_U,                                       /* PG_U_IDX             3 */
218                 X86_PG_A,                                       /* PG_A_IDX             4 */
219                 X86_PG_M,                                       /* PG_M_IDX             5 */
220                 X86_PG_PS,                                      /* PG_PS_IDX3           6 */
221                 X86_PG_G,                                       /* PG_G_IDX             7 */
222                 X86_PG_AVAIL1,                                  /* PG_AVAIL1_IDX        8 */
223                 X86_PG_AVAIL2,                                  /* PG_AVAIL2_IDX        9 */
224                 X86_PG_AVAIL3,                                  /* PG_AVAIL3_IDX        10 */
225                 X86_PG_NC_PWT | X86_PG_NC_PCD,                  /* PG_N_IDX     11 */
226 };
227 /*
228  * Crashdump maps.
229  */
230 static pt_entry_t *pt_crashdumpmap;
231 static caddr_t crashdumpmap;
232
233 static int pmap_yield_count = 64;
234 SYSCTL_INT(_machdep, OID_AUTO, pmap_yield_count, CTLFLAG_RW,
235     &pmap_yield_count, 0, "Yield during init_pt/release");
236 static int pmap_mmu_optimize = 0;
237 SYSCTL_INT(_machdep, OID_AUTO, pmap_mmu_optimize, CTLFLAG_RW,
238     &pmap_mmu_optimize, 0, "Share page table pages when possible");
239
240 #define DISABLE_PSE
241
242 /* Standard user access funtions */
243 extern int std_copyinstr (const void *udaddr, void *kaddr, size_t len,
244     size_t *lencopied);
245 extern int std_copyin (const void *udaddr, void *kaddr, size_t len);
246 extern int std_copyout (const void *kaddr, void *udaddr, size_t len);
247 extern int std_fubyte (const void *base);
248 extern int std_subyte (void *base, int byte);
249 extern long std_fuword (const void *base);
250 extern int std_suword (void *base, long word);
251 extern int std_suword32 (void *base, int word);
252
253 static void pv_hold(pv_entry_t pv);
254 static int _pv_hold_try(pv_entry_t pv
255                                 PMAP_DEBUG_DECL);
256 static void pv_drop(pv_entry_t pv);
257 static void _pv_lock(pv_entry_t pv
258                                 PMAP_DEBUG_DECL);
259 static void pv_unlock(pv_entry_t pv);
260 static pv_entry_t _pv_alloc(pmap_t pmap, vm_pindex_t pindex, int *isnew
261                                 PMAP_DEBUG_DECL);
262 static pv_entry_t _pv_get(pmap_t pmap, vm_pindex_t pindex
263                                 PMAP_DEBUG_DECL);
264 static pv_entry_t pv_get_try(pmap_t pmap, vm_pindex_t pindex, int *errorp);
265 static pv_entry_t pv_find(pmap_t pmap, vm_pindex_t pindex);
266 static void pv_put(pv_entry_t pv);
267 static void pv_free(pv_entry_t pv);
268 static void *pv_pte_lookup(pv_entry_t pv, vm_pindex_t pindex);
269 static pv_entry_t pmap_allocpte(pmap_t pmap, vm_pindex_t ptepindex,
270                       pv_entry_t *pvpp);
271 static pv_entry_t pmap_allocpte_seg(pmap_t pmap, vm_pindex_t ptepindex,
272                       pv_entry_t *pvpp, vm_map_entry_t entry, vm_offset_t va);
273 static void pmap_remove_pv_pte(pv_entry_t pv, pv_entry_t pvp,
274                       struct pmap_inval_info *info);
275 static vm_page_t pmap_remove_pv_page(pv_entry_t pv);
276 static int pmap_release_pv(pv_entry_t pv, pv_entry_t pvp);
277
278 struct pmap_scan_info;
279 static void pmap_remove_callback(pmap_t pmap, struct pmap_scan_info *info,
280                       pv_entry_t pte_pv, pv_entry_t pt_pv, int sharept,
281                       vm_offset_t va, pt_entry_t *ptep, void *arg __unused);
282 static void pmap_protect_callback(pmap_t pmap, struct pmap_scan_info *info,
283                       pv_entry_t pte_pv, pv_entry_t pt_pv, int sharept,
284                       vm_offset_t va, pt_entry_t *ptep, void *arg __unused);
285
286 static void i386_protection_init (void);
287 static void create_pagetables(vm_paddr_t *firstaddr);
288 static void pmap_remove_all (vm_page_t m);
289 static boolean_t pmap_testbit (vm_page_t m, int bit);
290
291 static pt_entry_t * pmap_pte_quick (pmap_t pmap, vm_offset_t va);
292 static vm_offset_t pmap_kmem_choose(vm_offset_t addr);
293
294 static void pmap_pinit_defaults(struct pmap *pmap);
295
296 static unsigned pdir4mb;
297
298 static int
299 pv_entry_compare(pv_entry_t pv1, pv_entry_t pv2)
300 {
301         if (pv1->pv_pindex < pv2->pv_pindex)
302                 return(-1);
303         if (pv1->pv_pindex > pv2->pv_pindex)
304                 return(1);
305         return(0);
306 }
307
308 RB_GENERATE2(pv_entry_rb_tree, pv_entry, pv_entry,
309              pv_entry_compare, vm_pindex_t, pv_pindex);
310
311 static __inline
312 void
313 pmap_page_stats_adding(vm_page_t m)
314 {
315         globaldata_t gd = mycpu;
316
317         if (TAILQ_EMPTY(&m->md.pv_list)) {
318                 ++gd->gd_vmtotal.t_arm;
319         } else if (TAILQ_FIRST(&m->md.pv_list) ==
320                    TAILQ_LAST(&m->md.pv_list, md_page_pv_list)) {
321                 ++gd->gd_vmtotal.t_armshr;
322                 ++gd->gd_vmtotal.t_avmshr;
323         } else {
324                 ++gd->gd_vmtotal.t_avmshr;
325         }
326 }
327
328 static __inline
329 void
330 pmap_page_stats_deleting(vm_page_t m)
331 {
332         globaldata_t gd = mycpu;
333
334         if (TAILQ_EMPTY(&m->md.pv_list)) {
335                 --gd->gd_vmtotal.t_arm;
336         } else if (TAILQ_FIRST(&m->md.pv_list) ==
337                    TAILQ_LAST(&m->md.pv_list, md_page_pv_list)) {
338                 --gd->gd_vmtotal.t_armshr;
339                 --gd->gd_vmtotal.t_avmshr;
340         } else {
341                 --gd->gd_vmtotal.t_avmshr;
342         }
343 }
344
345 /*
346  * Move the kernel virtual free pointer to the next
347  * 2MB.  This is used to help improve performance
348  * by using a large (2MB) page for much of the kernel
349  * (.text, .data, .bss)
350  */
351 static
352 vm_offset_t
353 pmap_kmem_choose(vm_offset_t addr)
354 {
355         vm_offset_t newaddr = addr;
356
357         newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1);
358         return newaddr;
359 }
360
361 /*
362  * pmap_pte_quick:
363  *
364  *      Super fast pmap_pte routine best used when scanning the pv lists.
365  *      This eliminates many course-grained invltlb calls.  Note that many of
366  *      the pv list scans are across different pmaps and it is very wasteful
367  *      to do an entire invltlb when checking a single mapping.
368  */
369 static __inline pt_entry_t *pmap_pte(pmap_t pmap, vm_offset_t va);
370
371 static
372 pt_entry_t *
373 pmap_pte_quick(pmap_t pmap, vm_offset_t va)
374 {
375         return pmap_pte(pmap, va);
376 }
377
378 /*
379  * Returns the pindex of a page table entry (representing a terminal page).
380  * There are NUPTE_TOTAL page table entries possible (a huge number)
381  *
382  * x86-64 has a 48-bit address space, where bit 47 is sign-extended out.
383  * We want to properly translate negative KVAs.
384  */
385 static __inline
386 vm_pindex_t
387 pmap_pte_pindex(vm_offset_t va)
388 {
389         return ((va >> PAGE_SHIFT) & (NUPTE_TOTAL - 1));
390 }
391
392 /*
393  * Returns the pindex of a page table.
394  */
395 static __inline
396 vm_pindex_t
397 pmap_pt_pindex(vm_offset_t va)
398 {
399         return (NUPTE_TOTAL + ((va >> PDRSHIFT) & (NUPT_TOTAL - 1)));
400 }
401
402 /*
403  * Returns the pindex of a page directory.
404  */
405 static __inline
406 vm_pindex_t
407 pmap_pd_pindex(vm_offset_t va)
408 {
409         return (NUPTE_TOTAL + NUPT_TOTAL +
410                 ((va >> PDPSHIFT) & (NUPD_TOTAL - 1)));
411 }
412
413 static __inline
414 vm_pindex_t
415 pmap_pdp_pindex(vm_offset_t va)
416 {
417         return (NUPTE_TOTAL + NUPT_TOTAL + NUPD_TOTAL +
418                 ((va >> PML4SHIFT) & (NUPDP_TOTAL - 1)));
419 }
420
421 static __inline
422 vm_pindex_t
423 pmap_pml4_pindex(void)
424 {
425         return (NUPTE_TOTAL + NUPT_TOTAL + NUPD_TOTAL + NUPDP_TOTAL);
426 }
427
428 /*
429  * Return various clipped indexes for a given VA
430  *
431  * Returns the index of a pte in a page table, representing a terminal
432  * page.
433  */
434 static __inline
435 vm_pindex_t
436 pmap_pte_index(vm_offset_t va)
437 {
438         return ((va >> PAGE_SHIFT) & ((1ul << NPTEPGSHIFT) - 1));
439 }
440
441 /*
442  * Returns the index of a pt in a page directory, representing a page
443  * table.
444  */
445 static __inline
446 vm_pindex_t
447 pmap_pt_index(vm_offset_t va)
448 {
449         return ((va >> PDRSHIFT) & ((1ul << NPDEPGSHIFT) - 1));
450 }
451
452 /*
453  * Returns the index of a pd in a page directory page, representing a page
454  * directory.
455  */
456 static __inline
457 vm_pindex_t
458 pmap_pd_index(vm_offset_t va)
459 {
460         return ((va >> PDPSHIFT) & ((1ul << NPDPEPGSHIFT) - 1));
461 }
462
463 /*
464  * Returns the index of a pdp in the pml4 table, representing a page
465  * directory page.
466  */
467 static __inline
468 vm_pindex_t
469 pmap_pdp_index(vm_offset_t va)
470 {
471         return ((va >> PML4SHIFT) & ((1ul << NPML4EPGSHIFT) - 1));
472 }
473
474 /*
475  * Generic procedure to index a pte from a pt, pd, or pdp.
476  *
477  * NOTE: Normally passed pindex as pmap_xx_index().  pmap_xx_pindex() is NOT
478  *       a page table page index but is instead of PV lookup index.
479  */
480 static
481 void *
482 pv_pte_lookup(pv_entry_t pv, vm_pindex_t pindex)
483 {
484         pt_entry_t *pte;
485
486         pte = (pt_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(pv->pv_m));
487         return(&pte[pindex]);
488 }
489
490 /*
491  * Return pointer to PDP slot in the PML4
492  */
493 static __inline
494 pml4_entry_t *
495 pmap_pdp(pmap_t pmap, vm_offset_t va)
496 {
497         return (&pmap->pm_pml4[pmap_pdp_index(va)]);
498 }
499
500 /*
501  * Return pointer to PD slot in the PDP given a pointer to the PDP
502  */
503 static __inline
504 pdp_entry_t *
505 pmap_pdp_to_pd(pml4_entry_t pdp_pte, vm_offset_t va)
506 {
507         pdp_entry_t *pd;
508
509         pd = (pdp_entry_t *)PHYS_TO_DMAP(pdp_pte & PG_FRAME);
510         return (&pd[pmap_pd_index(va)]);
511 }
512
513 /*
514  * Return pointer to PD slot in the PDP.
515  */
516 static __inline
517 pdp_entry_t *
518 pmap_pd(pmap_t pmap, vm_offset_t va)
519 {
520         pml4_entry_t *pdp;
521
522         pdp = pmap_pdp(pmap, va);
523         if ((*pdp & pmap->pmap_bits[PG_V_IDX]) == 0)
524                 return NULL;
525         return (pmap_pdp_to_pd(*pdp, va));
526 }
527
528 /*
529  * Return pointer to PT slot in the PD given a pointer to the PD
530  */
531 static __inline
532 pd_entry_t *
533 pmap_pd_to_pt(pdp_entry_t pd_pte, vm_offset_t va)
534 {
535         pd_entry_t *pt;
536
537         pt = (pd_entry_t *)PHYS_TO_DMAP(pd_pte & PG_FRAME);
538         return (&pt[pmap_pt_index(va)]);
539 }
540
541 /*
542  * Return pointer to PT slot in the PD
543  *
544  * SIMPLE PMAP NOTE: Simple pmaps (embedded in objects) do not have PDPs,
545  *                   so we cannot lookup the PD via the PDP.  Instead we
546  *                   must look it up via the pmap.
547  */
548 static __inline
549 pd_entry_t *
550 pmap_pt(pmap_t pmap, vm_offset_t va)
551 {
552         pdp_entry_t *pd;
553         pv_entry_t pv;
554         vm_pindex_t pd_pindex;
555
556         if (pmap->pm_flags & PMAP_FLAG_SIMPLE) {
557                 pd_pindex = pmap_pd_pindex(va);
558                 spin_lock(&pmap->pm_spin);
559                 pv = pv_entry_rb_tree_RB_LOOKUP(&pmap->pm_pvroot, pd_pindex);
560                 spin_unlock(&pmap->pm_spin);
561                 if (pv == NULL || pv->pv_m == NULL)
562                         return NULL;
563                 return (pmap_pd_to_pt(VM_PAGE_TO_PHYS(pv->pv_m), va));
564         } else {
565                 pd = pmap_pd(pmap, va);
566                 if (pd == NULL || (*pd & pmap->pmap_bits[PG_V_IDX]) == 0)
567                          return NULL;
568                 return (pmap_pd_to_pt(*pd, va));
569         }
570 }
571
572 /*
573  * Return pointer to PTE slot in the PT given a pointer to the PT
574  */
575 static __inline
576 pt_entry_t *
577 pmap_pt_to_pte(pd_entry_t pt_pte, vm_offset_t va)
578 {
579         pt_entry_t *pte;
580
581         pte = (pt_entry_t *)PHYS_TO_DMAP(pt_pte & PG_FRAME);
582         return (&pte[pmap_pte_index(va)]);
583 }
584
585 /*
586  * Return pointer to PTE slot in the PT
587  */
588 static __inline
589 pt_entry_t *
590 pmap_pte(pmap_t pmap, vm_offset_t va)
591 {
592         pd_entry_t *pt;
593
594         pt = pmap_pt(pmap, va);
595         if (pt == NULL || (*pt & pmap->pmap_bits[PG_V_IDX]) == 0)
596                  return NULL;
597         if ((*pt & pmap->pmap_bits[PG_PS_IDX]) != 0)
598                 return ((pt_entry_t *)pt);
599         return (pmap_pt_to_pte(*pt, va));
600 }
601
602 /*
603  * Of all the layers (PTE, PT, PD, PDP, PML4) the best one to cache is
604  * the PT layer.  This will speed up core pmap operations considerably.
605  *
606  * NOTE: The pmap spinlock does not need to be held but the passed-in pv
607  *       must be in a known associated state (typically by being locked when
608  *       the pmap spinlock isn't held).  We allow the race for that case.
609  */
610 static __inline
611 void
612 pv_cache(pv_entry_t pv, vm_pindex_t pindex)
613 {
614         if (pindex >= pmap_pt_pindex(0) && pindex <= pmap_pd_pindex(0))
615                 pv->pv_pmap->pm_pvhint = pv;
616 }
617
618
619 /*
620  * KVM - return address of PT slot in PD
621  */
622 static __inline
623 pd_entry_t *
624 vtopt(vm_offset_t va)
625 {
626         uint64_t mask = ((1ul << (NPDEPGSHIFT + NPDPEPGSHIFT +
627                                   NPML4EPGSHIFT)) - 1);
628
629         return (PDmap + ((va >> PDRSHIFT) & mask));
630 }
631
632 /*
633  * KVM - return address of PTE slot in PT
634  */
635 static __inline
636 pt_entry_t *
637 vtopte(vm_offset_t va)
638 {
639         uint64_t mask = ((1ul << (NPTEPGSHIFT + NPDEPGSHIFT +
640                                   NPDPEPGSHIFT + NPML4EPGSHIFT)) - 1);
641
642         return (PTmap + ((va >> PAGE_SHIFT) & mask));
643 }
644
645 static uint64_t
646 allocpages(vm_paddr_t *firstaddr, long n)
647 {
648         uint64_t ret;
649
650         ret = *firstaddr;
651         bzero((void *)ret, n * PAGE_SIZE);
652         *firstaddr += n * PAGE_SIZE;
653         return (ret);
654 }
655
656 static
657 void
658 create_pagetables(vm_paddr_t *firstaddr)
659 {
660         long i;         /* must be 64 bits */
661         long nkpt_base;
662         long nkpt_phys;
663         int j;
664
665         /*
666          * We are running (mostly) V=P at this point
667          *
668          * Calculate NKPT - number of kernel page tables.  We have to
669          * accomodoate prealloction of the vm_page_array, dump bitmap,
670          * MSGBUF_SIZE, and other stuff.  Be generous.
671          *
672          * Maxmem is in pages.
673          *
674          * ndmpdp is the number of 1GB pages we wish to map.
675          */
676         ndmpdp = (ptoa(Maxmem) + NBPDP - 1) >> PDPSHIFT;
677         if (ndmpdp < 4)         /* Minimum 4GB of dirmap */
678                 ndmpdp = 4;
679         KKASSERT(ndmpdp <= NKPDPE * NPDEPG);
680
681         /*
682          * Starting at the beginning of kvm (not KERNBASE).
683          */
684         nkpt_phys = (Maxmem * sizeof(struct vm_page) + NBPDR - 1) / NBPDR;
685         nkpt_phys += (Maxmem * sizeof(struct pv_entry) + NBPDR - 1) / NBPDR;
686         nkpt_phys += ((nkpt + nkpt + 1 + NKPML4E + NKPDPE + NDMPML4E +
687                        ndmpdp) + 511) / 512;
688         nkpt_phys += 128;
689
690         /*
691          * Starting at KERNBASE - map 2G worth of page table pages.
692          * KERNBASE is offset -2G from the end of kvm.
693          */
694         nkpt_base = (NPDPEPG - KPDPI) * NPTEPG; /* typically 2 x 512 */
695
696         /*
697          * Allocate pages
698          */
699         KPTbase = allocpages(firstaddr, nkpt_base);
700         KPTphys = allocpages(firstaddr, nkpt_phys);
701         KPML4phys = allocpages(firstaddr, 1);
702         KPDPphys = allocpages(firstaddr, NKPML4E);
703         KPDphys = allocpages(firstaddr, NKPDPE);
704
705         /*
706          * Calculate the page directory base for KERNBASE,
707          * that is where we start populating the page table pages.
708          * Basically this is the end - 2.
709          */
710         KPDbase = KPDphys + ((NKPDPE - (NPDPEPG - KPDPI)) << PAGE_SHIFT);
711
712         DMPDPphys = allocpages(firstaddr, NDMPML4E);
713         if ((amd_feature & AMDID_PAGE1GB) == 0)
714                 DMPDphys = allocpages(firstaddr, ndmpdp);
715         dmaplimit = (vm_paddr_t)ndmpdp << PDPSHIFT;
716
717         /*
718          * Fill in the underlying page table pages for the area around
719          * KERNBASE.  This remaps low physical memory to KERNBASE.
720          *
721          * Read-only from zero to physfree
722          * XXX not fully used, underneath 2M pages
723          */
724         for (i = 0; (i << PAGE_SHIFT) < *firstaddr; i++) {
725                 ((pt_entry_t *)KPTbase)[i] = i << PAGE_SHIFT;
726                 ((pt_entry_t *)KPTbase)[i] |=
727                     pmap_bits_default[PG_RW_IDX] |
728                     pmap_bits_default[PG_V_IDX] |
729                     pmap_bits_default[PG_G_IDX];
730         }
731
732         /*
733          * Now map the initial kernel page tables.  One block of page
734          * tables is placed at the beginning of kernel virtual memory,
735          * and another block is placed at KERNBASE to map the kernel binary,
736          * data, bss, and initial pre-allocations.
737          */
738         for (i = 0; i < nkpt_base; i++) {
739                 ((pd_entry_t *)KPDbase)[i] = KPTbase + (i << PAGE_SHIFT);
740                 ((pd_entry_t *)KPDbase)[i] |=
741                     pmap_bits_default[PG_RW_IDX] |
742                     pmap_bits_default[PG_V_IDX];
743         }
744         for (i = 0; i < nkpt_phys; i++) {
745                 ((pd_entry_t *)KPDphys)[i] = KPTphys + (i << PAGE_SHIFT);
746                 ((pd_entry_t *)KPDphys)[i] |=
747                     pmap_bits_default[PG_RW_IDX] |
748                     pmap_bits_default[PG_V_IDX];
749         }
750
751         /*
752          * Map from zero to end of allocations using 2M pages as an
753          * optimization.  This will bypass some of the KPTBase pages
754          * above in the KERNBASE area.
755          */
756         for (i = 0; (i << PDRSHIFT) < *firstaddr; i++) {
757                 ((pd_entry_t *)KPDbase)[i] = i << PDRSHIFT;
758                 ((pd_entry_t *)KPDbase)[i] |=
759                     pmap_bits_default[PG_RW_IDX] |
760                     pmap_bits_default[PG_V_IDX] |
761                     pmap_bits_default[PG_PS_IDX] |
762                     pmap_bits_default[PG_G_IDX];
763         }
764
765         /*
766          * And connect up the PD to the PDP.  The kernel pmap is expected
767          * to pre-populate all of its PDs.  See NKPDPE in vmparam.h.
768          */
769         for (i = 0; i < NKPDPE; i++) {
770                 ((pdp_entry_t *)KPDPphys)[NPDPEPG - NKPDPE + i] =
771                                 KPDphys + (i << PAGE_SHIFT);
772                 ((pdp_entry_t *)KPDPphys)[NPDPEPG - NKPDPE + i] |=
773                     pmap_bits_default[PG_RW_IDX] |
774                     pmap_bits_default[PG_V_IDX] |
775                     pmap_bits_default[PG_U_IDX];
776         }
777
778         /*
779          * Now set up the direct map space using either 2MB or 1GB pages
780          * Preset PG_M and PG_A because demotion expects it.
781          *
782          * When filling in entries in the PD pages make sure any excess
783          * entries are set to zero as we allocated enough PD pages
784          */
785         if ((amd_feature & AMDID_PAGE1GB) == 0) {
786                 for (i = 0; i < NPDEPG * ndmpdp; i++) {
787                         ((pd_entry_t *)DMPDphys)[i] = i << PDRSHIFT;
788                         ((pd_entry_t *)DMPDphys)[i] |=
789                             pmap_bits_default[PG_RW_IDX] |
790                             pmap_bits_default[PG_V_IDX] |
791                             pmap_bits_default[PG_PS_IDX] |
792                             pmap_bits_default[PG_G_IDX] |
793                             pmap_bits_default[PG_M_IDX] |
794                             pmap_bits_default[PG_A_IDX];
795                 }
796
797                 /*
798                  * And the direct map space's PDP
799                  */
800                 for (i = 0; i < ndmpdp; i++) {
801                         ((pdp_entry_t *)DMPDPphys)[i] = DMPDphys +
802                                                         (i << PAGE_SHIFT);
803                         ((pdp_entry_t *)DMPDPphys)[i] |=
804                             pmap_bits_default[PG_RW_IDX] |
805                             pmap_bits_default[PG_V_IDX] |
806                             pmap_bits_default[PG_U_IDX];
807                 }
808         } else {
809                 for (i = 0; i < ndmpdp; i++) {
810                         ((pdp_entry_t *)DMPDPphys)[i] =
811                                                 (vm_paddr_t)i << PDPSHIFT;
812                         ((pdp_entry_t *)DMPDPphys)[i] |=
813                             pmap_bits_default[PG_RW_IDX] |
814                             pmap_bits_default[PG_V_IDX] |
815                             pmap_bits_default[PG_PS_IDX] |
816                             pmap_bits_default[PG_G_IDX] |
817                             pmap_bits_default[PG_M_IDX] |
818                             pmap_bits_default[PG_A_IDX];
819                 }
820         }
821
822         /* And recursively map PML4 to itself in order to get PTmap */
823         ((pdp_entry_t *)KPML4phys)[PML4PML4I] = KPML4phys;
824         ((pdp_entry_t *)KPML4phys)[PML4PML4I] |=
825             pmap_bits_default[PG_RW_IDX] |
826             pmap_bits_default[PG_V_IDX] |
827             pmap_bits_default[PG_U_IDX];
828
829         /*
830          * Connect the Direct Map slots up to the PML4
831          */
832         for (j = 0; j < NDMPML4E; ++j) {
833                 ((pdp_entry_t *)KPML4phys)[DMPML4I + j] =
834                     (DMPDPphys + ((vm_paddr_t)j << PML4SHIFT)) |
835                     pmap_bits_default[PG_RW_IDX] |
836                     pmap_bits_default[PG_V_IDX] |
837                     pmap_bits_default[PG_U_IDX];
838         }
839
840         /*
841          * Connect the KVA slot up to the PML4
842          */
843         ((pdp_entry_t *)KPML4phys)[KPML4I] = KPDPphys;
844         ((pdp_entry_t *)KPML4phys)[KPML4I] |=
845             pmap_bits_default[PG_RW_IDX] |
846             pmap_bits_default[PG_V_IDX] |
847             pmap_bits_default[PG_U_IDX];
848 }
849
850 /*
851  *      Bootstrap the system enough to run with virtual memory.
852  *
853  *      On the i386 this is called after mapping has already been enabled
854  *      and just syncs the pmap module with what has already been done.
855  *      [We can't call it easily with mapping off since the kernel is not
856  *      mapped with PA == VA, hence we would have to relocate every address
857  *      from the linked base (virtual) address "KERNBASE" to the actual
858  *      (physical) address starting relative to 0]
859  */
860 void
861 pmap_bootstrap(vm_paddr_t *firstaddr)
862 {
863         vm_offset_t va;
864         pt_entry_t *pte;
865
866         KvaStart = VM_MIN_KERNEL_ADDRESS;
867         KvaEnd = VM_MAX_KERNEL_ADDRESS;
868         KvaSize = KvaEnd - KvaStart;
869
870         avail_start = *firstaddr;
871
872         /*
873          * Create an initial set of page tables to run the kernel in.
874          */
875         create_pagetables(firstaddr);
876
877         virtual2_start = KvaStart;
878         virtual2_end = PTOV_OFFSET;
879
880         virtual_start = (vm_offset_t) PTOV_OFFSET + *firstaddr;
881         virtual_start = pmap_kmem_choose(virtual_start);
882
883         virtual_end = VM_MAX_KERNEL_ADDRESS;
884
885         /* XXX do %cr0 as well */
886         load_cr4(rcr4() | CR4_PGE | CR4_PSE);
887         load_cr3(KPML4phys);
888
889         /*
890          * Initialize protection array.
891          */
892         i386_protection_init();
893
894         /*
895          * The kernel's pmap is statically allocated so we don't have to use
896          * pmap_create, which is unlikely to work correctly at this part of
897          * the boot sequence (XXX and which no longer exists).
898          */
899         kernel_pmap.pm_pml4 = (pdp_entry_t *) (PTOV_OFFSET + KPML4phys);
900         kernel_pmap.pm_count = 1;
901         kernel_pmap.pm_active = (cpumask_t)-1 & ~CPUMASK_LOCK;
902         RB_INIT(&kernel_pmap.pm_pvroot);
903         spin_init(&kernel_pmap.pm_spin);
904         lwkt_token_init(&kernel_pmap.pm_token, "kpmap_tok");
905
906         /*
907          * Reserve some special page table entries/VA space for temporary
908          * mapping of pages.
909          */
910 #define SYSMAP(c, p, v, n)      \
911         v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n);
912
913         va = virtual_start;
914         pte = vtopte(va);
915
916         /*
917          * CMAP1/CMAP2 are used for zeroing and copying pages.
918          */
919         SYSMAP(caddr_t, CMAP1, CADDR1, 1)
920
921         /*
922          * Crashdump maps.
923          */
924         SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS);
925
926         /*
927          * ptvmmap is used for reading arbitrary physical pages via
928          * /dev/mem.
929          */
930         SYSMAP(caddr_t, ptmmap, ptvmmap, 1)
931
932         /*
933          * msgbufp is used to map the system message buffer.
934          * XXX msgbufmap is not used.
935          */
936         SYSMAP(struct msgbuf *, msgbufmap, msgbufp,
937                atop(round_page(MSGBUF_SIZE)))
938
939         virtual_start = va;
940
941         *CMAP1 = 0;
942
943         /*
944          * PG_G is terribly broken on SMP because we IPI invltlb's in some
945          * cases rather then invl1pg.  Actually, I don't even know why it
946          * works under UP because self-referential page table mappings
947          */
948 //      pgeflag = 0;
949
950 /*
951  * Initialize the 4MB page size flag
952  */
953 //      pseflag = 0;
954 /*
955  * The 4MB page version of the initial
956  * kernel page mapping.
957  */
958         pdir4mb = 0;
959
960 #if !defined(DISABLE_PSE)
961         if (cpu_feature & CPUID_PSE) {
962                 pt_entry_t ptditmp;
963                 /*
964                  * Note that we have enabled PSE mode
965                  */
966 //              pseflag = kernel_pmap.pmap_bits[PG_PS_IDX];
967                 ptditmp = *(PTmap + x86_64_btop(KERNBASE));
968                 ptditmp &= ~(NBPDR - 1);
969                 ptditmp |= pmap_bits_default[PG_V_IDX] |
970                     pmap_bits_default[PG_RW_IDX] |
971                     pmap_bits_default[PG_PS_IDX] |
972                     pmap_bits_default[PG_U_IDX];
973 //                  pgeflag;
974                 pdir4mb = ptditmp;
975         }
976 #endif
977         cpu_invltlb();
978
979         /* Initialize the PAT MSR */
980         pmap_init_pat();
981
982         pmap_pinit_defaults(&kernel_pmap);
983 }
984
985 /*
986  * Setup the PAT MSR.
987  */
988 void
989 pmap_init_pat(void)
990 {
991         uint64_t pat_msr;
992         u_long cr0, cr4;
993
994         /*
995          * Default values mapping PATi,PCD,PWT bits at system reset.
996          * The default values effectively ignore the PATi bit by
997          * repeating the encodings for 0-3 in 4-7, and map the PCD
998          * and PWT bit combinations to the expected PAT types.
999          */
1000         pat_msr = PAT_VALUE(0, PAT_WRITE_BACK) |        /* 000 */
1001                   PAT_VALUE(1, PAT_WRITE_THROUGH) |     /* 001 */
1002                   PAT_VALUE(2, PAT_UNCACHED) |          /* 010 */
1003                   PAT_VALUE(3, PAT_UNCACHEABLE) |       /* 011 */
1004                   PAT_VALUE(4, PAT_WRITE_BACK) |        /* 100 */
1005                   PAT_VALUE(5, PAT_WRITE_THROUGH) |     /* 101 */
1006                   PAT_VALUE(6, PAT_UNCACHED) |          /* 110 */
1007                   PAT_VALUE(7, PAT_UNCACHEABLE);        /* 111 */
1008         pat_pte_index[PAT_WRITE_BACK]   = 0;
1009         pat_pte_index[PAT_WRITE_THROUGH]= 0         | X86_PG_NC_PWT;
1010         pat_pte_index[PAT_UNCACHED]     = X86_PG_NC_PCD;
1011         pat_pte_index[PAT_UNCACHEABLE]  = X86_PG_NC_PCD | X86_PG_NC_PWT;
1012         pat_pte_index[PAT_WRITE_PROTECTED] = pat_pte_index[PAT_UNCACHEABLE];
1013         pat_pte_index[PAT_WRITE_COMBINING] = pat_pte_index[PAT_UNCACHEABLE];
1014
1015         if (cpu_feature & CPUID_PAT) {
1016                 /*
1017                  * If we support the PAT then set-up entries for
1018                  * WRITE_PROTECTED and WRITE_COMBINING using bit patterns
1019                  * 4 and 5.
1020                  */
1021                 pat_msr = (pat_msr & ~PAT_MASK(4)) |
1022                           PAT_VALUE(4, PAT_WRITE_PROTECTED);
1023                 pat_msr = (pat_msr & ~PAT_MASK(5)) |
1024                           PAT_VALUE(5, PAT_WRITE_COMBINING);
1025                 pat_pte_index[PAT_WRITE_PROTECTED] = X86_PG_PTE_PAT | 0;
1026                 pat_pte_index[PAT_WRITE_COMBINING] = X86_PG_PTE_PAT | X86_PG_NC_PWT;
1027
1028                 /*
1029                  * Then enable the PAT
1030                  */
1031
1032                 /* Disable PGE. */
1033                 cr4 = rcr4();
1034                 load_cr4(cr4 & ~CR4_PGE);
1035
1036                 /* Disable caches (CD = 1, NW = 0). */
1037                 cr0 = rcr0();
1038                 load_cr0((cr0 & ~CR0_NW) | CR0_CD);
1039
1040                 /* Flushes caches and TLBs. */
1041                 wbinvd();
1042                 cpu_invltlb();
1043
1044                 /* Update PAT and index table. */
1045                 wrmsr(MSR_PAT, pat_msr);
1046
1047                 /* Flush caches and TLBs again. */
1048                 wbinvd();
1049                 cpu_invltlb();
1050
1051                 /* Restore caches and PGE. */
1052                 load_cr0(cr0);
1053                 load_cr4(cr4);
1054                 PatMsr = pat_msr;
1055         }
1056 }
1057
1058 /*
1059  * Set 4mb pdir for mp startup
1060  */
1061 void
1062 pmap_set_opt(void)
1063 {
1064         if (cpu_feature & CPUID_PSE) {
1065                 load_cr4(rcr4() | CR4_PSE);
1066                 if (pdir4mb && mycpu->gd_cpuid == 0) {  /* only on BSP */
1067                         cpu_invltlb();
1068                 }
1069         }
1070 }
1071
1072 /*
1073  *      Initialize the pmap module.
1074  *      Called by vm_init, to initialize any structures that the pmap
1075  *      system needs to map virtual memory.
1076  *      pmap_init has been enhanced to support in a fairly consistant
1077  *      way, discontiguous physical memory.
1078  */
1079 void
1080 pmap_init(void)
1081 {
1082         int i;
1083         int initial_pvs;
1084
1085         /*
1086          * Allocate memory for random pmap data structures.  Includes the
1087          * pv_head_table.
1088          */
1089
1090         for (i = 0; i < vm_page_array_size; i++) {
1091                 vm_page_t m;
1092
1093                 m = &vm_page_array[i];
1094                 TAILQ_INIT(&m->md.pv_list);
1095         }
1096
1097         /*
1098          * init the pv free list
1099          */
1100         initial_pvs = vm_page_array_size;
1101         if (initial_pvs < MINPV)
1102                 initial_pvs = MINPV;
1103         pvzone = &pvzone_store;
1104         pvinit = (void *)kmem_alloc(&kernel_map,
1105                                     initial_pvs * sizeof (struct pv_entry));
1106         zbootinit(pvzone, "PV ENTRY", sizeof (struct pv_entry),
1107                   pvinit, initial_pvs);
1108
1109         /*
1110          * Now it is safe to enable pv_table recording.
1111          */
1112         pmap_initialized = TRUE;
1113 }
1114
1115 /*
1116  * Initialize the address space (zone) for the pv_entries.  Set a
1117  * high water mark so that the system can recover from excessive
1118  * numbers of pv entries.
1119  */
1120 void
1121 pmap_init2(void)
1122 {
1123         int shpgperproc = PMAP_SHPGPERPROC;
1124         int entry_max;
1125
1126         TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc);
1127         pv_entry_max = shpgperproc * maxproc + vm_page_array_size;
1128         TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max);
1129         pv_entry_high_water = 9 * (pv_entry_max / 10);
1130
1131         /*
1132          * Subtract out pages already installed in the zone (hack)
1133          */
1134         entry_max = pv_entry_max - vm_page_array_size;
1135         if (entry_max <= 0)
1136                 entry_max = 1;
1137
1138         zinitna(pvzone, &pvzone_obj, NULL, 0, entry_max, ZONE_INTERRUPT, 1);
1139 }
1140
1141 /*
1142  * Typically used to initialize a fictitious page by vm/device_pager.c
1143  */
1144 void
1145 pmap_page_init(struct vm_page *m)
1146 {
1147         vm_page_init(m);
1148         TAILQ_INIT(&m->md.pv_list);
1149 }
1150
1151 /***************************************************
1152  * Low level helper routines.....
1153  ***************************************************/
1154
1155 /*
1156  * this routine defines the region(s) of memory that should
1157  * not be tested for the modified bit.
1158  */
1159 static __inline
1160 int
1161 pmap_track_modified(vm_pindex_t pindex)
1162 {
1163         vm_offset_t va = (vm_offset_t)pindex << PAGE_SHIFT;
1164         if ((va < clean_sva) || (va >= clean_eva)) 
1165                 return 1;
1166         else
1167                 return 0;
1168 }
1169
1170 /*
1171  * Extract the physical page address associated with the map/VA pair.
1172  * The page must be wired for this to work reliably.
1173  *
1174  * XXX for the moment we're using pv_find() instead of pv_get(), as
1175  *     callers might be expecting non-blocking operation.
1176  */
1177 vm_paddr_t 
1178 pmap_extract(pmap_t pmap, vm_offset_t va)
1179 {
1180         vm_paddr_t rtval;
1181         pv_entry_t pt_pv;
1182         pt_entry_t *ptep;
1183
1184         rtval = 0;
1185         if (va >= VM_MAX_USER_ADDRESS) {
1186                 /*
1187                  * Kernel page directories might be direct-mapped and
1188                  * there is typically no PV tracking of pte's
1189                  */
1190                 pd_entry_t *pt;
1191
1192                 pt = pmap_pt(pmap, va);
1193                 if (pt && (*pt & pmap->pmap_bits[PG_V_IDX])) {
1194                         if (*pt & pmap->pmap_bits[PG_PS_IDX]) {
1195                                 rtval = *pt & PG_PS_FRAME;
1196                                 rtval |= va & PDRMASK;
1197                         } else {
1198                                 ptep = pmap_pt_to_pte(*pt, va);
1199                                 if (*pt & pmap->pmap_bits[PG_V_IDX]) {
1200                                         rtval = *ptep & PG_FRAME;
1201                                         rtval |= va & PAGE_MASK;
1202                                 }
1203                         }
1204                 }
1205         } else {
1206                 /*
1207                  * User pages currently do not direct-map the page directory
1208                  * and some pages might not used managed PVs.  But all PT's
1209                  * will have a PV.
1210                  */
1211                 pt_pv = pv_find(pmap, pmap_pt_pindex(va));
1212                 if (pt_pv) {
1213                         ptep = pv_pte_lookup(pt_pv, pmap_pte_index(va));
1214                         if (*ptep & pmap->pmap_bits[PG_V_IDX]) {
1215                                 rtval = *ptep & PG_FRAME;
1216                                 rtval |= va & PAGE_MASK;
1217                         }
1218                         pv_drop(pt_pv);
1219                 }
1220         }
1221         return rtval;
1222 }
1223
1224 /*
1225  * Similar to extract but checks protections, SMP-friendly short-cut for
1226  * vm_fault_page[_quick]().  Can return NULL to cause the caller to
1227  * fall-through to the real fault code.
1228  *
1229  * The returned page, if not NULL, is held (and not busied).
1230  */
1231 vm_page_t
1232 pmap_fault_page_quick(pmap_t pmap, vm_offset_t va, vm_prot_t prot)
1233 {
1234         if (pmap && va < VM_MAX_USER_ADDRESS) {
1235                 pv_entry_t pt_pv;
1236                 pv_entry_t pte_pv;
1237                 pt_entry_t *ptep;
1238                 pt_entry_t req;
1239                 vm_page_t m;
1240                 int error;
1241
1242                 req = pmap->pmap_bits[PG_V_IDX] |
1243                       pmap->pmap_bits[PG_U_IDX];
1244                 if (prot & VM_PROT_WRITE)
1245                         req |= pmap->pmap_bits[PG_RW_IDX];
1246
1247                 pt_pv = pv_find(pmap, pmap_pt_pindex(va));
1248                 if (pt_pv == NULL)
1249                         return (NULL);
1250                 ptep = pv_pte_lookup(pt_pv, pmap_pte_index(va));
1251                 if ((*ptep & req) != req) {
1252                         pv_drop(pt_pv);
1253                         return (NULL);
1254                 }
1255                 pte_pv = pv_get_try(pmap, pmap_pte_pindex(va), &error);
1256                 if (pte_pv && error == 0) {
1257                         m = pte_pv->pv_m;
1258                         vm_page_hold(m);
1259                         if (prot & VM_PROT_WRITE)
1260                                 vm_page_dirty(m);
1261                         pv_put(pte_pv);
1262                 } else if (pte_pv) {
1263                         pv_drop(pte_pv);
1264                         m = NULL;
1265                 } else {
1266                         m = NULL;
1267                 }
1268                 pv_drop(pt_pv);
1269                 return(m);
1270         } else {
1271                 return(NULL);
1272         }
1273 }
1274
1275 /*
1276  * Extract the physical page address associated kernel virtual address.
1277  */
1278 vm_paddr_t
1279 pmap_kextract(vm_offset_t va)
1280 {
1281         pd_entry_t pt;          /* pt entry in pd */
1282         vm_paddr_t pa;
1283
1284         if (va >= DMAP_MIN_ADDRESS && va < DMAP_MAX_ADDRESS) {
1285                 pa = DMAP_TO_PHYS(va);
1286         } else {
1287                 pt = *vtopt(va);
1288                 if (pt & kernel_pmap.pmap_bits[PG_PS_IDX]) {
1289                         pa = (pt & PG_PS_FRAME) | (va & PDRMASK);
1290                 } else {
1291                         /*
1292                          * Beware of a concurrent promotion that changes the
1293                          * PDE at this point!  For example, vtopte() must not
1294                          * be used to access the PTE because it would use the
1295                          * new PDE.  It is, however, safe to use the old PDE
1296                          * because the page table page is preserved by the
1297                          * promotion.
1298                          */
1299                         pa = *pmap_pt_to_pte(pt, va);
1300                         pa = (pa & PG_FRAME) | (va & PAGE_MASK);
1301                 }
1302         }
1303         return pa;
1304 }
1305
1306 /***************************************************
1307  * Low level mapping routines.....
1308  ***************************************************/
1309
1310 /*
1311  * Routine: pmap_kenter
1312  * Function:
1313  *      Add a wired page to the KVA
1314  *      NOTE! note that in order for the mapping to take effect -- you
1315  *      should do an invltlb after doing the pmap_kenter().
1316  */
1317 void 
1318 pmap_kenter(vm_offset_t va, vm_paddr_t pa)
1319 {
1320         pt_entry_t *pte;
1321         pt_entry_t npte;
1322         pmap_inval_info info;
1323
1324         pmap_inval_init(&info);                         /* XXX remove */
1325         npte = pa |
1326             kernel_pmap.pmap_bits[PG_RW_IDX] |
1327             kernel_pmap.pmap_bits[PG_V_IDX];
1328 //          pgeflag;
1329         pte = vtopte(va);
1330         pmap_inval_interlock(&info, &kernel_pmap, va);  /* XXX remove */
1331         *pte = npte;
1332         pmap_inval_deinterlock(&info, &kernel_pmap);    /* XXX remove */
1333         pmap_inval_done(&info);                         /* XXX remove */
1334 }
1335
1336 /*
1337  * Routine: pmap_kenter_quick
1338  * Function:
1339  *      Similar to pmap_kenter(), except we only invalidate the
1340  *      mapping on the current CPU.
1341  */
1342 void
1343 pmap_kenter_quick(vm_offset_t va, vm_paddr_t pa)
1344 {
1345         pt_entry_t *pte;
1346         pt_entry_t npte;
1347
1348         npte = pa |
1349             kernel_pmap.pmap_bits[PG_RW_IDX] |
1350             kernel_pmap.pmap_bits[PG_V_IDX];
1351 //          pgeflag;
1352         pte = vtopte(va);
1353         *pte = npte;
1354         cpu_invlpg((void *)va);
1355 }
1356
1357 void
1358 pmap_kenter_sync(vm_offset_t va)
1359 {
1360         pmap_inval_info info;
1361
1362         pmap_inval_init(&info);
1363         pmap_inval_interlock(&info, &kernel_pmap, va);
1364         pmap_inval_deinterlock(&info, &kernel_pmap);
1365         pmap_inval_done(&info);
1366 }
1367
1368 void
1369 pmap_kenter_sync_quick(vm_offset_t va)
1370 {
1371         cpu_invlpg((void *)va);
1372 }
1373
1374 /*
1375  * remove a page from the kernel pagetables
1376  */
1377 void
1378 pmap_kremove(vm_offset_t va)
1379 {
1380         pt_entry_t *pte;
1381         pmap_inval_info info;
1382
1383         pmap_inval_init(&info);
1384         pte = vtopte(va);
1385         pmap_inval_interlock(&info, &kernel_pmap, va);
1386         (void)pte_load_clear(pte);
1387         pmap_inval_deinterlock(&info, &kernel_pmap);
1388         pmap_inval_done(&info);
1389 }
1390
1391 void
1392 pmap_kremove_quick(vm_offset_t va)
1393 {
1394         pt_entry_t *pte;
1395         pte = vtopte(va);
1396         (void)pte_load_clear(pte);
1397         cpu_invlpg((void *)va);
1398 }
1399
1400 /*
1401  * XXX these need to be recoded.  They are not used in any critical path.
1402  */
1403 void
1404 pmap_kmodify_rw(vm_offset_t va)
1405 {
1406         atomic_set_long(vtopte(va), kernel_pmap.pmap_bits[PG_RW_IDX]);
1407         cpu_invlpg((void *)va);
1408 }
1409
1410 /* NOT USED
1411 void
1412 pmap_kmodify_nc(vm_offset_t va)
1413 {
1414         atomic_set_long(vtopte(va), PG_N);
1415         cpu_invlpg((void *)va);
1416 }
1417 */
1418
1419 /*
1420  * Used to map a range of physical addresses into kernel virtual
1421  * address space during the low level boot, typically to map the
1422  * dump bitmap, message buffer, and vm_page_array.
1423  *
1424  * These mappings are typically made at some pointer after the end of the
1425  * kernel text+data.
1426  *
1427  * We could return PHYS_TO_DMAP(start) here and not allocate any
1428  * via (*virtp), but then kmem from userland and kernel dumps won't
1429  * have access to the related pointers.
1430  */
1431 vm_offset_t
1432 pmap_map(vm_offset_t *virtp, vm_paddr_t start, vm_paddr_t end, int prot)
1433 {
1434         vm_offset_t va;
1435         vm_offset_t va_start;
1436
1437         /*return PHYS_TO_DMAP(start);*/
1438
1439         va_start = *virtp;
1440         va = va_start;
1441
1442         while (start < end) {
1443                 pmap_kenter_quick(va, start);
1444                 va += PAGE_SIZE;
1445                 start += PAGE_SIZE;
1446         }
1447         *virtp = va;
1448         return va_start;
1449 }
1450
1451 #define PMAP_CLFLUSH_THRESHOLD  (2 * 1024 * 1024)
1452
1453 /*
1454  * Remove the specified set of pages from the data and instruction caches.
1455  *
1456  * In contrast to pmap_invalidate_cache_range(), this function does not
1457  * rely on the CPU's self-snoop feature, because it is intended for use
1458  * when moving pages into a different cache domain.
1459  */
1460 void
1461 pmap_invalidate_cache_pages(vm_page_t *pages, int count)
1462 {
1463         vm_offset_t daddr, eva;
1464         int i;
1465
1466         if (count >= PMAP_CLFLUSH_THRESHOLD / PAGE_SIZE ||
1467             (cpu_feature & CPUID_CLFSH) == 0)
1468                 wbinvd();
1469         else {
1470                 cpu_mfence();
1471                 for (i = 0; i < count; i++) {
1472                         daddr = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(pages[i]));
1473                         eva = daddr + PAGE_SIZE;
1474                         for (; daddr < eva; daddr += cpu_clflush_line_size)
1475                                 clflush(daddr);
1476                 }
1477                 cpu_mfence();
1478         }
1479 }
1480
1481 void
1482 pmap_invalidate_cache_range(vm_offset_t sva, vm_offset_t eva)
1483 {
1484         KASSERT((sva & PAGE_MASK) == 0,
1485             ("pmap_invalidate_cache_range: sva not page-aligned"));
1486         KASSERT((eva & PAGE_MASK) == 0,
1487             ("pmap_invalidate_cache_range: eva not page-aligned"));
1488
1489         if (cpu_feature & CPUID_SS) {
1490                 ; /* If "Self Snoop" is supported, do nothing. */
1491         } else {
1492                 /* Globally invalidate caches */
1493                 cpu_wbinvd_on_all_cpus();
1494         }
1495 }
1496 void
1497 pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
1498 {
1499         smp_invlpg_range(pmap->pm_active, sva, eva);
1500 }
1501
1502 /*
1503  * Add a list of wired pages to the kva
1504  * this routine is only used for temporary
1505  * kernel mappings that do not need to have
1506  * page modification or references recorded.
1507  * Note that old mappings are simply written
1508  * over.  The page *must* be wired.
1509  */
1510 void
1511 pmap_qenter(vm_offset_t va, vm_page_t *m, int count)
1512 {
1513         vm_offset_t end_va;
1514
1515         end_va = va + count * PAGE_SIZE;
1516                 
1517         while (va < end_va) {
1518                 pt_entry_t *pte;
1519
1520                 pte = vtopte(va);
1521                 *pte = VM_PAGE_TO_PHYS(*m) |
1522                     kernel_pmap.pmap_bits[PG_RW_IDX] |
1523                     kernel_pmap.pmap_bits[PG_V_IDX] |
1524                     kernel_pmap.pmap_cache_bits[(*m)->pat_mode];
1525 //              pgeflag;
1526                 cpu_invlpg((void *)va);
1527                 va += PAGE_SIZE;
1528                 m++;
1529         }
1530         smp_invltlb();
1531 }
1532
1533 /*
1534  * This routine jerks page mappings from the
1535  * kernel -- it is meant only for temporary mappings.
1536  *
1537  * MPSAFE, INTERRUPT SAFE (cluster callback)
1538  */
1539 void
1540 pmap_qremove(vm_offset_t va, int count)
1541 {
1542         vm_offset_t end_va;
1543
1544         end_va = va + count * PAGE_SIZE;
1545
1546         while (va < end_va) {
1547                 pt_entry_t *pte;
1548
1549                 pte = vtopte(va);
1550                 (void)pte_load_clear(pte);
1551                 cpu_invlpg((void *)va);
1552                 va += PAGE_SIZE;
1553         }
1554         smp_invltlb();
1555 }
1556
1557 /*
1558  * Create a new thread and optionally associate it with a (new) process.
1559  * NOTE! the new thread's cpu may not equal the current cpu.
1560  */
1561 void
1562 pmap_init_thread(thread_t td)
1563 {
1564         /* enforce pcb placement & alignment */
1565         td->td_pcb = (struct pcb *)(td->td_kstack + td->td_kstack_size) - 1;
1566         td->td_pcb = (struct pcb *)((intptr_t)td->td_pcb & ~(intptr_t)0xF);
1567         td->td_savefpu = &td->td_pcb->pcb_save;
1568         td->td_sp = (char *)td->td_pcb; /* no -16 */
1569 }
1570
1571 /*
1572  * This routine directly affects the fork perf for a process.
1573  */
1574 void
1575 pmap_init_proc(struct proc *p)
1576 {
1577 }
1578
1579 static void
1580 pmap_pinit_defaults(struct pmap *pmap)
1581 {
1582         bcopy(pmap_bits_default, pmap->pmap_bits,
1583               sizeof(pmap_bits_default));
1584         bcopy(protection_codes, pmap->protection_codes,
1585               sizeof(protection_codes));
1586         bcopy(pat_pte_index, pmap->pmap_cache_bits,
1587               sizeof(pat_pte_index));
1588         pmap->pmap_cache_mask = X86_PG_NC_PWT | X86_PG_NC_PCD | X86_PG_PTE_PAT;
1589         pmap->copyinstr = std_copyinstr;
1590         pmap->copyin = std_copyin;
1591         pmap->copyout = std_copyout;
1592         pmap->fubyte = std_fubyte;
1593         pmap->subyte = std_subyte;
1594         pmap->fuword = std_fuword;
1595         pmap->suword = std_suword;
1596         pmap->suword32 = std_suword32;
1597 }
1598 /*
1599  * Initialize pmap0/vmspace0.  This pmap is not added to pmap_list because
1600  * it, and IdlePTD, represents the template used to update all other pmaps.
1601  *
1602  * On architectures where the kernel pmap is not integrated into the user
1603  * process pmap, this pmap represents the process pmap, not the kernel pmap.
1604  * kernel_pmap should be used to directly access the kernel_pmap.
1605  */
1606 void
1607 pmap_pinit0(struct pmap *pmap)
1608 {
1609         pmap->pm_pml4 = (pml4_entry_t *)(PTOV_OFFSET + KPML4phys);
1610         pmap->pm_count = 1;
1611         pmap->pm_active = 0;
1612         pmap->pm_pvhint = NULL;
1613         RB_INIT(&pmap->pm_pvroot);
1614         spin_init(&pmap->pm_spin);
1615         lwkt_token_init(&pmap->pm_token, "pmap_tok");
1616         bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
1617         pmap_pinit_defaults(pmap);
1618 }
1619
1620 /*
1621  * Initialize a preallocated and zeroed pmap structure,
1622  * such as one in a vmspace structure.
1623  */
1624 static void
1625 pmap_pinit_simple(struct pmap *pmap)
1626 {
1627         /*
1628          * Misc initialization
1629          */
1630         pmap->pm_count = 1;
1631         pmap->pm_active = 0;
1632         pmap->pm_pvhint = NULL;
1633         pmap->pm_flags = PMAP_FLAG_SIMPLE;
1634
1635         pmap_pinit_defaults(pmap);
1636
1637         /*
1638          * Don't blow up locks/tokens on re-use (XXX fix/use drop code
1639          * for this).
1640          */
1641         if (pmap->pm_pmlpv == NULL) {
1642                 RB_INIT(&pmap->pm_pvroot);
1643                 bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
1644                 spin_init(&pmap->pm_spin);
1645                 lwkt_token_init(&pmap->pm_token, "pmap_tok");
1646         }
1647 }
1648
1649 void
1650 pmap_pinit(struct pmap *pmap)
1651 {
1652         pv_entry_t pv;
1653         int j;
1654
1655         if (pmap->pm_pmlpv) {
1656                 if (pmap->pmap_bits[TYPE_IDX] != REGULAR_PMAP) {
1657                         pmap_puninit(pmap);
1658                 }
1659         }
1660
1661         pmap_pinit_simple(pmap);
1662         pmap->pm_flags &= ~PMAP_FLAG_SIMPLE;
1663
1664         /*
1665          * No need to allocate page table space yet but we do need a valid
1666          * page directory table.
1667          */
1668         if (pmap->pm_pml4 == NULL) {
1669                 pmap->pm_pml4 =
1670                     (pml4_entry_t *)kmem_alloc_pageable(&kernel_map, PAGE_SIZE);
1671         }
1672
1673         /*
1674          * Allocate the page directory page, which wires it even though
1675          * it isn't being entered into some higher level page table (it
1676          * being the highest level).  If one is already cached we don't
1677          * have to do anything.
1678          */
1679         if ((pv = pmap->pm_pmlpv) == NULL) {
1680                 pv = pmap_allocpte(pmap, pmap_pml4_pindex(), NULL);
1681                 pmap->pm_pmlpv = pv;
1682                 pmap_kenter((vm_offset_t)pmap->pm_pml4,
1683                             VM_PAGE_TO_PHYS(pv->pv_m));
1684                 pv_put(pv);
1685
1686                 /*
1687                  * Install DMAP and KMAP.
1688                  */
1689                 for (j = 0; j < NDMPML4E; ++j) {
1690                         pmap->pm_pml4[DMPML4I + j] =
1691                             (DMPDPphys + ((vm_paddr_t)j << PML4SHIFT)) |
1692                             pmap->pmap_bits[PG_RW_IDX] |
1693                             pmap->pmap_bits[PG_V_IDX] |
1694                             pmap->pmap_bits[PG_U_IDX];
1695                 }
1696                 pmap->pm_pml4[KPML4I] = KPDPphys |
1697                     pmap->pmap_bits[PG_RW_IDX] |
1698                     pmap->pmap_bits[PG_V_IDX] |
1699                     pmap->pmap_bits[PG_U_IDX];
1700
1701                 /*
1702                  * install self-referential address mapping entry
1703                  */
1704                 pmap->pm_pml4[PML4PML4I] = VM_PAGE_TO_PHYS(pv->pv_m) |
1705                     pmap->pmap_bits[PG_V_IDX] |
1706                     pmap->pmap_bits[PG_RW_IDX] |
1707                     pmap->pmap_bits[PG_A_IDX] |
1708                     pmap->pmap_bits[PG_M_IDX];
1709         } else {
1710                 KKASSERT(pv->pv_m->flags & PG_MAPPED);
1711                 KKASSERT(pv->pv_m->flags & PG_WRITEABLE);
1712         }
1713         KKASSERT(pmap->pm_pml4[255] == 0);
1714         KKASSERT(RB_ROOT(&pmap->pm_pvroot) == pv);
1715         KKASSERT(pv->pv_entry.rbe_left == NULL);
1716         KKASSERT(pv->pv_entry.rbe_right == NULL);
1717 }
1718
1719 /*
1720  * Clean up a pmap structure so it can be physically freed.  This routine
1721  * is called by the vmspace dtor function.  A great deal of pmap data is
1722  * left passively mapped to improve vmspace management so we have a bit
1723  * of cleanup work to do here.
1724  */
1725 void
1726 pmap_puninit(pmap_t pmap)
1727 {
1728         pv_entry_t pv;
1729         vm_page_t p;
1730
1731         KKASSERT(pmap->pm_active == 0);
1732         if ((pv = pmap->pm_pmlpv) != NULL) {
1733                 if (pv_hold_try(pv) == 0)
1734                         pv_lock(pv);
1735                 KKASSERT(pv == pmap->pm_pmlpv);
1736                 p = pmap_remove_pv_page(pv);
1737                 pv_free(pv);
1738                 pmap_kremove((vm_offset_t)pmap->pm_pml4);
1739                 vm_page_busy_wait(p, FALSE, "pgpun");
1740                 KKASSERT(p->flags & (PG_FICTITIOUS|PG_UNMANAGED));
1741                 vm_page_unwire(p, 0);
1742                 vm_page_flag_clear(p, PG_MAPPED | PG_WRITEABLE);
1743
1744                 /*
1745                  * XXX eventually clean out PML4 static entries and
1746                  * use vm_page_free_zero()
1747                  */
1748                 vm_page_free(p);
1749                 pmap->pm_pmlpv = NULL;
1750         }
1751         if (pmap->pm_pml4) {
1752                 KKASSERT(pmap->pm_pml4 != (void *)(PTOV_OFFSET + KPML4phys));
1753                 kmem_free(&kernel_map, (vm_offset_t)pmap->pm_pml4, PAGE_SIZE);
1754                 pmap->pm_pml4 = NULL;
1755         }
1756         KKASSERT(pmap->pm_stats.resident_count == 0);
1757         KKASSERT(pmap->pm_stats.wired_count == 0);
1758 }
1759
1760 /*
1761  * Wire in kernel global address entries.  To avoid a race condition
1762  * between pmap initialization and pmap_growkernel, this procedure
1763  * adds the pmap to the master list (which growkernel scans to update),
1764  * then copies the template.
1765  */
1766 void
1767 pmap_pinit2(struct pmap *pmap)
1768 {
1769         spin_lock(&pmap_spin);
1770         TAILQ_INSERT_TAIL(&pmap_list, pmap, pm_pmnode);
1771         spin_unlock(&pmap_spin);
1772 }
1773
1774 /*
1775  * This routine is called when various levels in the page table need to
1776  * be populated.  This routine cannot fail.
1777  *
1778  * This function returns two locked pv_entry's, one representing the
1779  * requested pv and one representing the requested pv's parent pv.  If
1780  * the pv did not previously exist it will be mapped into its parent
1781  * and wired, otherwise no additional wire count will be added.
1782  */
1783 static
1784 pv_entry_t
1785 pmap_allocpte(pmap_t pmap, vm_pindex_t ptepindex, pv_entry_t *pvpp)
1786 {
1787         pt_entry_t *ptep;
1788         pv_entry_t pv;
1789         pv_entry_t pvp;
1790         vm_pindex_t pt_pindex;
1791         vm_page_t m;
1792         int isnew;
1793         int ispt;
1794
1795         /*
1796          * If the pv already exists and we aren't being asked for the
1797          * parent page table page we can just return it.  A locked+held pv
1798          * is returned.  The pv will also have a second hold related to the
1799          * pmap association that we don't have to worry about.
1800          */
1801         ispt = 0;
1802         pv = pv_alloc(pmap, ptepindex, &isnew);
1803         if (isnew == 0 && pvpp == NULL)
1804                 return(pv);
1805
1806         /*
1807          * Special case terminal PVs.  These are not page table pages so
1808          * no vm_page is allocated (the caller supplied the vm_page).  If
1809          * pvpp is non-NULL we are being asked to also removed the pt_pv
1810          * for this pv.
1811          *
1812          * Note that pt_pv's are only returned for user VAs. We assert that
1813          * a pt_pv is not being requested for kernel VAs.
1814          */
1815         if (ptepindex < pmap_pt_pindex(0)) {
1816                 if (ptepindex >= NUPTE_USER)
1817                         KKASSERT(pvpp == NULL);
1818                 else
1819                         KKASSERT(pvpp != NULL);
1820                 if (pvpp) {
1821                         pt_pindex = NUPTE_TOTAL + (ptepindex >> NPTEPGSHIFT);
1822                         pvp = pmap_allocpte(pmap, pt_pindex, NULL);
1823                         if (isnew)
1824                                 vm_page_wire_quick(pvp->pv_m);
1825                         *pvpp = pvp;
1826                 } else {
1827                         pvp = NULL;
1828                 }
1829                 return(pv);
1830         }
1831
1832         /*
1833          * Non-terminal PVs allocate a VM page to represent the page table,
1834          * so we have to resolve pvp and calculate ptepindex for the pvp
1835          * and then for the page table entry index in the pvp for
1836          * fall-through.
1837          */
1838         if (ptepindex < pmap_pd_pindex(0)) {
1839                 /*
1840                  * pv is PT, pvp is PD
1841                  */
1842                 ptepindex = (ptepindex - pmap_pt_pindex(0)) >> NPDEPGSHIFT;
1843                 ptepindex += NUPTE_TOTAL + NUPT_TOTAL;
1844                 pvp = pmap_allocpte(pmap, ptepindex, NULL);
1845                 if (!isnew)
1846                         goto notnew;
1847
1848                 /*
1849                  * PT index in PD
1850                  */
1851                 ptepindex = pv->pv_pindex - pmap_pt_pindex(0);
1852                 ptepindex &= ((1ul << NPDEPGSHIFT) - 1);
1853                 ispt = 1;
1854         } else if (ptepindex < pmap_pdp_pindex(0)) {
1855                 /*
1856                  * pv is PD, pvp is PDP
1857                  *
1858                  * SIMPLE PMAP NOTE: Simple pmaps do not allocate above
1859                  *                   the PD.
1860                  */
1861                 ptepindex = (ptepindex - pmap_pd_pindex(0)) >> NPDPEPGSHIFT;
1862                 ptepindex += NUPTE_TOTAL + NUPT_TOTAL + NUPD_TOTAL;
1863
1864                 if (pmap->pm_flags & PMAP_FLAG_SIMPLE) {
1865                         KKASSERT(pvpp == NULL);
1866                         pvp = NULL;
1867                 } else {
1868                         pvp = pmap_allocpte(pmap, ptepindex, NULL);
1869                 }
1870                 if (!isnew)
1871                         goto notnew;
1872
1873                 /*
1874                  * PD index in PDP
1875                  */
1876                 ptepindex = pv->pv_pindex - pmap_pd_pindex(0);
1877                 ptepindex &= ((1ul << NPDPEPGSHIFT) - 1);
1878         } else if (ptepindex < pmap_pml4_pindex()) {
1879                 /*
1880                  * pv is PDP, pvp is the root pml4 table
1881                  */
1882                 pvp = pmap_allocpte(pmap, pmap_pml4_pindex(), NULL);
1883                 if (!isnew)
1884                         goto notnew;
1885
1886                 /*
1887                  * PDP index in PML4
1888                  */
1889                 ptepindex = pv->pv_pindex - pmap_pdp_pindex(0);
1890                 ptepindex &= ((1ul << NPML4EPGSHIFT) - 1);
1891         } else {
1892                 /*
1893                  * pv represents the top-level PML4, there is no parent.
1894                  */
1895                 pvp = NULL;
1896                 if (!isnew)
1897                         goto notnew;
1898         }
1899
1900         /*
1901          * This code is only reached if isnew is TRUE and this is not a
1902          * terminal PV.  We need to allocate a vm_page for the page table
1903          * at this level and enter it into the parent page table.
1904          *
1905          * page table pages are marked PG_WRITEABLE and PG_MAPPED.
1906          */
1907         for (;;) {
1908                 m = vm_page_alloc(NULL, pv->pv_pindex,
1909                                   VM_ALLOC_NORMAL | VM_ALLOC_SYSTEM |
1910                                   VM_ALLOC_INTERRUPT);
1911                 if (m)
1912                         break;
1913                 vm_wait(0);
1914         }
1915         vm_page_spin_lock(m);
1916         pmap_page_stats_adding(m);
1917         TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
1918         pv->pv_m = m;
1919         vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE);
1920         vm_page_spin_unlock(m);
1921         vm_page_unmanage(m);    /* m must be spinunlocked */
1922
1923         if ((m->flags & PG_ZERO) == 0) {
1924                 pmap_zero_page(VM_PAGE_TO_PHYS(m));
1925         }
1926 #ifdef PMAP_DEBUG
1927         else {
1928                 pmap_page_assertzero(VM_PAGE_TO_PHYS(m));
1929         }
1930 #endif
1931         m->valid = VM_PAGE_BITS_ALL;
1932         vm_page_flag_clear(m, PG_ZERO);
1933         vm_page_wire(m);        /* wire for mapping in parent */
1934
1935         /*
1936          * Wire the page into pvp, bump the wire-count for pvp's page table
1937          * page.  Bump the resident_count for the pmap.  There is no pvp
1938          * for the top level, address the pm_pml4[] array directly.
1939          *
1940          * If the caller wants the parent we return it, otherwise
1941          * we just put it away.
1942          *
1943          * No interlock is needed for pte 0 -> non-zero.
1944          *
1945          * In the situation where *ptep is valid we might have an unmanaged
1946          * page table page shared from another page table which we need to
1947          * unshare before installing our private page table page.
1948          */
1949         if (pvp) {
1950                 ptep = pv_pte_lookup(pvp, ptepindex);
1951                 if (*ptep & pmap->pmap_bits[PG_V_IDX]) {
1952                         pt_entry_t pte;
1953                         pmap_inval_info info;
1954
1955                         if (ispt == 0) {
1956                                 panic("pmap_allocpte: unexpected pte %p/%d",
1957                                       pvp, (int)ptepindex);
1958                         }
1959                         pmap_inval_init(&info);
1960                         pmap_inval_interlock(&info, pmap, (vm_offset_t)-1);
1961                         pte = pte_load_clear(ptep);
1962                         pmap_inval_deinterlock(&info, pmap);
1963                         pmap_inval_done(&info);
1964                         if (vm_page_unwire_quick(
1965                                         PHYS_TO_VM_PAGE(pte & PG_FRAME))) {
1966                                 panic("pmap_allocpte: shared pgtable "
1967                                       "pg bad wirecount");
1968                         }
1969                         atomic_add_long(&pmap->pm_stats.resident_count, -1);
1970                 } else {
1971                         vm_page_wire_quick(pvp->pv_m);
1972                 }
1973                 *ptep = VM_PAGE_TO_PHYS(m) |
1974                     (pmap->pmap_bits[PG_U_IDX] |
1975                     pmap->pmap_bits[PG_RW_IDX] |
1976                     pmap->pmap_bits[PG_V_IDX] |
1977                     pmap->pmap_bits[PG_A_IDX] |
1978                     pmap->pmap_bits[PG_M_IDX]);
1979         }
1980         vm_page_wakeup(m);
1981 notnew:
1982         if (pvpp)
1983                 *pvpp = pvp;
1984         else if (pvp)
1985                 pv_put(pvp);
1986         return (pv);
1987 }
1988
1989 /*
1990  * This version of pmap_allocpte() checks for possible segment optimizations
1991  * that would allow page-table sharing.  It can be called for terminal
1992  * page or page table page ptepindex's.
1993  *
1994  * The function is called with page table page ptepindex's for fictitious
1995  * and unmanaged terminal pages.  That is, we don't want to allocate a
1996  * terminal pv, we just want the pt_pv.  pvpp is usually passed as NULL
1997  * for this case.
1998  *
1999  * This function can return a pv and *pvpp associated with the passed in pmap
2000  * OR a pv and *pvpp associated with the shared pmap.  In the latter case
2001  * an unmanaged page table page will be entered into the pass in pmap.
2002  */
2003 static
2004 pv_entry_t
2005 pmap_allocpte_seg(pmap_t pmap, vm_pindex_t ptepindex, pv_entry_t *pvpp,
2006                   vm_map_entry_t entry, vm_offset_t va)
2007 {
2008         struct pmap_inval_info info;
2009         vm_object_t object;
2010         pmap_t obpmap;
2011         pmap_t *obpmapp;
2012         vm_offset_t b;
2013         pv_entry_t pte_pv;      /* in original or shared pmap */
2014         pv_entry_t pt_pv;       /* in original or shared pmap */
2015         pv_entry_t proc_pd_pv;  /* in original pmap */
2016         pv_entry_t proc_pt_pv;  /* in original pmap */
2017         pv_entry_t xpv;         /* PT in shared pmap */
2018         pd_entry_t *pt;         /* PT entry in PD of original pmap */
2019         pd_entry_t opte;        /* contents of *pt */
2020         pd_entry_t npte;        /* contents of *pt */
2021         vm_page_t m;
2022
2023 retry:
2024         /*
2025          * Basic tests, require a non-NULL vm_map_entry, require proper
2026          * alignment and type for the vm_map_entry, require that the
2027          * underlying object already be allocated.
2028          *
2029          * We currently allow any type of object to use this optimization.
2030          * The object itself does NOT have to be sized to a multiple of the
2031          * segment size, but the memory mapping does.
2032          *
2033          * XXX don't handle devices currently, because VM_PAGE_TO_PHYS()
2034          *     won't work as expected.
2035          */
2036         if (entry == NULL ||
2037             pmap_mmu_optimize == 0 ||                   /* not enabled */
2038             ptepindex >= pmap_pd_pindex(0) ||           /* not terminal */
2039             entry->inheritance != VM_INHERIT_SHARE ||   /* not shared */
2040             entry->maptype != VM_MAPTYPE_NORMAL ||      /* weird map type */
2041             entry->object.vm_object == NULL ||          /* needs VM object */
2042             entry->object.vm_object->type == OBJT_DEVICE ||     /* ick */
2043             entry->object.vm_object->type == OBJT_MGTDEVICE ||  /* ick */
2044             (entry->offset & SEG_MASK) ||               /* must be aligned */
2045             (entry->start & SEG_MASK)) {
2046                 return(pmap_allocpte(pmap, ptepindex, pvpp));
2047         }
2048
2049         /*
2050          * Make sure the full segment can be represented.
2051          */
2052         b = va & ~(vm_offset_t)SEG_MASK;
2053         if (b < entry->start && b + SEG_SIZE > entry->end)
2054                 return(pmap_allocpte(pmap, ptepindex, pvpp));
2055
2056         /*
2057          * If the full segment can be represented dive the VM object's
2058          * shared pmap, allocating as required.
2059          */
2060         object = entry->object.vm_object;
2061
2062         if (entry->protection & VM_PROT_WRITE)
2063                 obpmapp = &object->md.pmap_rw;
2064         else
2065                 obpmapp = &object->md.pmap_ro;
2066
2067         /*
2068          * We allocate what appears to be a normal pmap but because portions
2069          * of this pmap are shared with other unrelated pmaps we have to
2070          * set pm_active to point to all cpus.
2071          *
2072          * XXX Currently using pmap_spin to interlock the update, can't use
2073          *     vm_object_hold/drop because the token might already be held
2074          *     shared OR exclusive and we don't know.
2075          */
2076         while ((obpmap = *obpmapp) == NULL) {
2077                 obpmap = kmalloc(sizeof(*obpmap), M_OBJPMAP, M_WAITOK|M_ZERO);
2078                 pmap_pinit_simple(obpmap);
2079                 pmap_pinit2(obpmap);
2080                 spin_lock(&pmap_spin);
2081                 if (*obpmapp != NULL) {
2082                         /*
2083                          * Handle race
2084                          */
2085                         spin_unlock(&pmap_spin);
2086                         pmap_release(obpmap);
2087                         pmap_puninit(obpmap);
2088                         kfree(obpmap, M_OBJPMAP);
2089                 } else {
2090                         obpmap->pm_active = smp_active_mask;
2091                         *obpmapp = obpmap;
2092                         spin_unlock(&pmap_spin);
2093                 }
2094         }
2095
2096         /*
2097          * Layering is: PTE, PT, PD, PDP, PML4.  We have to return the
2098          * pte/pt using the shared pmap from the object but also adjust
2099          * the process pmap's page table page as a side effect.
2100          */
2101
2102         /*
2103          * Resolve the terminal PTE and PT in the shared pmap.  This is what
2104          * we will return.  This is true if ptepindex represents a terminal
2105          * page, otherwise pte_pv is actually the PT and pt_pv is actually
2106          * the PD.
2107          */
2108         pt_pv = NULL;
2109         pte_pv = pmap_allocpte(obpmap, ptepindex, &pt_pv);
2110         if (ptepindex >= pmap_pt_pindex(0))
2111                 xpv = pte_pv;
2112         else
2113                 xpv = pt_pv;
2114
2115         /*
2116          * Resolve the PD in the process pmap so we can properly share the
2117          * page table page.  Lock order is bottom-up (leaf first)!
2118          *
2119          * NOTE: proc_pt_pv can be NULL.
2120          */
2121         proc_pt_pv = pv_get(pmap, pmap_pt_pindex(b));
2122         proc_pd_pv = pmap_allocpte(pmap, pmap_pd_pindex(b), NULL);
2123
2124         /*
2125          * xpv is the page table page pv from the shared object
2126          * (for convenience).
2127          *
2128          * Calculate the pte value for the PT to load into the process PD.
2129          * If we have to change it we must properly dispose of the previous
2130          * entry.
2131          */
2132         pt = pv_pte_lookup(proc_pd_pv, pmap_pt_index(b));
2133         npte = VM_PAGE_TO_PHYS(xpv->pv_m) |
2134             (pmap->pmap_bits[PG_U_IDX] |
2135             pmap->pmap_bits[PG_RW_IDX] |
2136             pmap->pmap_bits[PG_V_IDX] |
2137             pmap->pmap_bits[PG_A_IDX] |
2138             pmap->pmap_bits[PG_M_IDX]);
2139
2140         /*
2141          * Dispose of previous page table page if it was local to the
2142          * process pmap.  If the old pt is not empty we cannot dispose of it
2143          * until we clean it out.  This case should not arise very often so
2144          * it is not optimized.
2145          */
2146         if (proc_pt_pv) {
2147                 if (proc_pt_pv->pv_m->wire_count != 1) {
2148                         pv_put(proc_pd_pv);
2149                         pv_put(proc_pt_pv);
2150                         pv_put(pt_pv);
2151                         pv_put(pte_pv);
2152                         pmap_remove(pmap,
2153                                     va & ~(vm_offset_t)SEG_MASK,
2154                                     (va + SEG_SIZE) & ~(vm_offset_t)SEG_MASK);
2155                         goto retry;
2156                 }
2157                 pmap_release_pv(proc_pt_pv, proc_pd_pv);
2158                 proc_pt_pv = NULL;
2159                 /* relookup */
2160                 pt = pv_pte_lookup(proc_pd_pv, pmap_pt_index(b));
2161         }
2162
2163         /*
2164          * Handle remaining cases.
2165          */
2166         if (*pt == 0) {
2167                 *pt = npte;
2168                 vm_page_wire_quick(xpv->pv_m);
2169                 vm_page_wire_quick(proc_pd_pv->pv_m);
2170                 atomic_add_long(&pmap->pm_stats.resident_count, 1);
2171         } else if (*pt != npte) {
2172                 pmap_inval_init(&info);
2173                 pmap_inval_interlock(&info, pmap, (vm_offset_t)-1);
2174
2175                 opte = pte_load_clear(pt);
2176                 KKASSERT(opte && opte != npte);
2177
2178                 *pt = npte;
2179                 vm_page_wire_quick(xpv->pv_m);  /* pgtable pg that is npte */
2180
2181                 /*
2182                  * Clean up opte, bump the wire_count for the process
2183                  * PD page representing the new entry if it was
2184                  * previously empty.
2185                  *
2186                  * If the entry was not previously empty and we have
2187                  * a PT in the proc pmap then opte must match that
2188                  * pt.  The proc pt must be retired (this is done
2189                  * later on in this procedure).
2190                  *
2191                  * NOTE: replacing valid pte, wire_count on proc_pd_pv
2192                  * stays the same.
2193                  */
2194                 KKASSERT(opte & pmap->pmap_bits[PG_V_IDX]);
2195                 m = PHYS_TO_VM_PAGE(opte & PG_FRAME);
2196                 if (vm_page_unwire_quick(m)) {
2197                         panic("pmap_allocpte_seg: "
2198                               "bad wire count %p",
2199                               m);
2200                 }
2201
2202                 pmap_inval_deinterlock(&info, pmap);
2203                 pmap_inval_done(&info);
2204         }
2205
2206         /*
2207          * The existing process page table was replaced and must be destroyed
2208          * here.
2209          */
2210         if (proc_pd_pv)
2211                 pv_put(proc_pd_pv);
2212         if (pvpp)
2213                 *pvpp = pt_pv;
2214         else
2215                 pv_put(pt_pv);
2216
2217         return (pte_pv);
2218 }
2219
2220 /*
2221  * Release any resources held by the given physical map.
2222  *
2223  * Called when a pmap initialized by pmap_pinit is being released.  Should
2224  * only be called if the map contains no valid mappings.
2225  *
2226  * Caller must hold pmap->pm_token
2227  */
2228 struct pmap_release_info {
2229         pmap_t  pmap;
2230         int     retry;
2231 };
2232
2233 static int pmap_release_callback(pv_entry_t pv, void *data);
2234
2235 void
2236 pmap_release(struct pmap *pmap)
2237 {
2238         struct pmap_release_info info;
2239
2240         KASSERT(pmap->pm_active == 0,
2241                 ("pmap still active! %016jx", (uintmax_t)pmap->pm_active));
2242
2243         spin_lock(&pmap_spin);
2244         TAILQ_REMOVE(&pmap_list, pmap, pm_pmnode);
2245         spin_unlock(&pmap_spin);
2246
2247         /*
2248          * Pull pv's off the RB tree in order from low to high and release
2249          * each page.
2250          */
2251         info.pmap = pmap;
2252         do {
2253                 info.retry = 0;
2254                 spin_lock(&pmap->pm_spin);
2255                 RB_SCAN(pv_entry_rb_tree, &pmap->pm_pvroot, NULL,
2256                         pmap_release_callback, &info);
2257                 spin_unlock(&pmap->pm_spin);
2258         } while (info.retry);
2259
2260
2261         /*
2262          * One resident page (the pml4 page) should remain.
2263          * No wired pages should remain.
2264          */
2265         KKASSERT(pmap->pm_stats.resident_count ==
2266                  ((pmap->pm_flags & PMAP_FLAG_SIMPLE) ? 0 : 1));
2267
2268         KKASSERT(pmap->pm_stats.wired_count == 0);
2269 }
2270
2271 static int
2272 pmap_release_callback(pv_entry_t pv, void *data)
2273 {
2274         struct pmap_release_info *info = data;
2275         pmap_t pmap = info->pmap;
2276         int r;
2277
2278         if (pv_hold_try(pv)) {
2279                 spin_unlock(&pmap->pm_spin);
2280         } else {
2281                 spin_unlock(&pmap->pm_spin);
2282                 pv_lock(pv);
2283         }
2284         if (pv->pv_pmap != pmap) {
2285                 pv_put(pv);
2286                 spin_lock(&pmap->pm_spin);
2287                 info->retry = 1;
2288                 return(-1);
2289         }
2290         r = pmap_release_pv(pv, NULL);
2291         spin_lock(&pmap->pm_spin);
2292         return(r);
2293 }
2294
2295 /*
2296  * Called with held (i.e. also locked) pv.  This function will dispose of
2297  * the lock along with the pv.
2298  *
2299  * If the caller already holds the locked parent page table for pv it
2300  * must pass it as pvp, allowing us to avoid a deadlock, else it can
2301  * pass NULL for pvp.
2302  */
2303 static int
2304 pmap_release_pv(pv_entry_t pv, pv_entry_t pvp)
2305 {
2306         vm_page_t p;
2307
2308         /*
2309          * The pmap is currently not spinlocked, pv is held+locked.
2310          * Remove the pv's page from its parent's page table.  The
2311          * parent's page table page's wire_count will be decremented.
2312          */
2313         pmap_remove_pv_pte(pv, pvp, NULL);
2314
2315         /*
2316          * Terminal pvs are unhooked from their vm_pages.  Because
2317          * terminal pages aren't page table pages they aren't wired
2318          * by us, so we have to be sure not to unwire them either.
2319          */
2320         if (pv->pv_pindex < pmap_pt_pindex(0)) {
2321                 pmap_remove_pv_page(pv);
2322                 goto skip;
2323         }
2324
2325         /*
2326          * We leave the top-level page table page cached, wired, and
2327          * mapped in the pmap until the dtor function (pmap_puninit())
2328          * gets called.
2329          *
2330          * Since we are leaving the top-level pv intact we need
2331          * to break out of what would otherwise be an infinite loop.
2332          */
2333         if (pv->pv_pindex == pmap_pml4_pindex()) {
2334                 pv_put(pv);
2335                 return(-1);
2336         }
2337
2338         /*
2339          * For page table pages (other than the top-level page),
2340          * remove and free the vm_page.  The representitive mapping
2341          * removed above by pmap_remove_pv_pte() did not undo the
2342          * last wire_count so we have to do that as well.
2343          */
2344         p = pmap_remove_pv_page(pv);
2345         vm_page_busy_wait(p, FALSE, "pmaprl");
2346         if (p->wire_count != 1) {
2347                 kprintf("p->wire_count was %016lx %d\n",
2348                         pv->pv_pindex, p->wire_count);
2349         }
2350         KKASSERT(p->wire_count == 1);
2351         KKASSERT(p->flags & PG_UNMANAGED);
2352
2353         vm_page_unwire(p, 0);
2354         KKASSERT(p->wire_count == 0);
2355
2356         /*
2357          * Theoretically this page, if not the pml4 page, should contain
2358          * all-zeros.  But its just too dangerous to mark it PG_ZERO.  Free
2359          * normally.
2360          */
2361         vm_page_free(p);
2362 skip:
2363         pv_free(pv);
2364         return 0;
2365 }
2366
2367 /*
2368  * This function will remove the pte associated with a pv from its parent.
2369  * Terminal pv's are supported.  The removal will be interlocked if info
2370  * is non-NULL.  The caller must dispose of pv instead of just unlocking
2371  * it.
2372  *
2373  * The wire count will be dropped on the parent page table.  The wire
2374  * count on the page being removed (pv->pv_m) from the parent page table
2375  * is NOT touched.  Note that terminal pages will not have any additional
2376  * wire counts while page table pages will have at least one representing
2377  * the mapping, plus others representing sub-mappings.
2378  *
2379  * NOTE: Cannot be called on kernel page table pages, only KVM terminal
2380  *       pages and user page table and terminal pages.
2381  *
2382  * The pv must be locked.
2383  *
2384  * XXX must lock parent pv's if they exist to remove pte XXX
2385  */
2386 static
2387 void
2388 pmap_remove_pv_pte(pv_entry_t pv, pv_entry_t pvp, struct pmap_inval_info *info)
2389 {
2390         vm_pindex_t ptepindex = pv->pv_pindex;
2391         pmap_t pmap = pv->pv_pmap;
2392         vm_page_t p;
2393         int gotpvp = 0;
2394
2395         KKASSERT(pmap);
2396
2397         if (ptepindex == pmap_pml4_pindex()) {
2398                 /*
2399                  * We are the top level pml4 table, there is no parent.
2400                  */
2401                 p = pmap->pm_pmlpv->pv_m;
2402         } else if (ptepindex >= pmap_pdp_pindex(0)) {
2403                 /*
2404                  * Remove a PDP page from the pml4e.  This can only occur
2405                  * with user page tables.  We do not have to lock the
2406                  * pml4 PV so just ignore pvp.
2407                  */
2408                 vm_pindex_t pml4_pindex;
2409                 vm_pindex_t pdp_index;
2410                 pml4_entry_t *pdp;
2411
2412                 pdp_index = ptepindex - pmap_pdp_pindex(0);
2413                 if (pvp == NULL) {
2414                         pml4_pindex = pmap_pml4_pindex();
2415                         pvp = pv_get(pv->pv_pmap, pml4_pindex);
2416                         KKASSERT(pvp);
2417                         gotpvp = 1;
2418                 }
2419                 pdp = &pmap->pm_pml4[pdp_index & ((1ul << NPML4EPGSHIFT) - 1)];
2420                 KKASSERT((*pdp & pmap->pmap_bits[PG_V_IDX]) != 0);
2421                 p = PHYS_TO_VM_PAGE(*pdp & PG_FRAME);
2422                 *pdp = 0;
2423                 KKASSERT(info == NULL);
2424         } else if (ptepindex >= pmap_pd_pindex(0)) {
2425                 /*
2426                  * Remove a PD page from the pdp
2427                  *
2428                  * SIMPLE PMAP NOTE: Non-existant pvp's are ok in the case
2429                  *                   of a simple pmap because it stops at
2430                  *                   the PD page.
2431                  */
2432                 vm_pindex_t pdp_pindex;
2433                 vm_pindex_t pd_index;
2434                 pdp_entry_t *pd;
2435
2436                 pd_index = ptepindex - pmap_pd_pindex(0);
2437
2438                 if (pvp == NULL) {
2439                         pdp_pindex = NUPTE_TOTAL + NUPT_TOTAL + NUPD_TOTAL +
2440                                      (pd_index >> NPML4EPGSHIFT);
2441                         pvp = pv_get(pv->pv_pmap, pdp_pindex);
2442                         if (pvp)
2443                                 gotpvp = 1;
2444                 }
2445                 if (pvp) {
2446                         pd = pv_pte_lookup(pvp, pd_index &
2447                                                 ((1ul << NPDPEPGSHIFT) - 1));
2448                         KKASSERT((*pd & pmap->pmap_bits[PG_V_IDX]) != 0);
2449                         p = PHYS_TO_VM_PAGE(*pd & PG_FRAME);
2450                         *pd = 0;
2451                 } else {
2452                         KKASSERT(pmap->pm_flags & PMAP_FLAG_SIMPLE);
2453                         p = pv->pv_m;           /* degenerate test later */
2454                 }
2455                 KKASSERT(info == NULL);
2456         } else if (ptepindex >= pmap_pt_pindex(0)) {
2457                 /*
2458                  *  Remove a PT page from the pd
2459                  */
2460                 vm_pindex_t pd_pindex;
2461                 vm_pindex_t pt_index;
2462                 pd_entry_t *pt;
2463
2464                 pt_index = ptepindex - pmap_pt_pindex(0);
2465
2466                 if (pvp == NULL) {
2467                         pd_pindex = NUPTE_TOTAL + NUPT_TOTAL +
2468                                     (pt_index >> NPDPEPGSHIFT);
2469                         pvp = pv_get(pv->pv_pmap, pd_pindex);
2470                         KKASSERT(pvp);
2471                         gotpvp = 1;
2472                 }
2473                 pt = pv_pte_lookup(pvp, pt_index & ((1ul << NPDPEPGSHIFT) - 1));
2474                 KKASSERT((*pt & pmap->pmap_bits[PG_V_IDX]) != 0);
2475                 p = PHYS_TO_VM_PAGE(*pt & PG_FRAME);
2476                 *pt = 0;
2477                 KKASSERT(info == NULL);
2478         } else {
2479                 /*
2480                  * Remove a PTE from the PT page
2481                  *
2482                  * NOTE: pv's must be locked bottom-up to avoid deadlocking.
2483                  *       pv is a pte_pv so we can safely lock pt_pv.
2484                  *
2485                  * NOTE: FICTITIOUS pages may have multiple physical mappings
2486                  *       so PHYS_TO_VM_PAGE() will not necessarily work for
2487                  *       terminal ptes.
2488                  */
2489                 vm_pindex_t pt_pindex;
2490                 pt_entry_t *ptep;
2491                 pt_entry_t pte;
2492                 vm_offset_t va;
2493
2494                 pt_pindex = ptepindex >> NPTEPGSHIFT;
2495                 va = (vm_offset_t)ptepindex << PAGE_SHIFT;
2496
2497                 if (ptepindex >= NUPTE_USER) {
2498                         ptep = vtopte(ptepindex << PAGE_SHIFT);
2499                         KKASSERT(pvp == NULL);
2500                 } else {
2501                         if (pvp == NULL) {
2502                                 pt_pindex = NUPTE_TOTAL +
2503                                             (ptepindex >> NPDPEPGSHIFT);
2504                                 pvp = pv_get(pv->pv_pmap, pt_pindex);
2505                                 KKASSERT(pvp);
2506                                 gotpvp = 1;
2507                         }
2508                         ptep = pv_pte_lookup(pvp, ptepindex &
2509                                                   ((1ul << NPDPEPGSHIFT) - 1));
2510                 }
2511
2512                 if (info)
2513                         pmap_inval_interlock(info, pmap, va);
2514                 pte = pte_load_clear(ptep);
2515                 if (info)
2516                         pmap_inval_deinterlock(info, pmap);
2517                 else
2518                         cpu_invlpg((void *)va);
2519
2520                 /*
2521                  * Now update the vm_page_t
2522                  */
2523                 if ((pte & (pmap->pmap_bits[PG_MANAGED_IDX] | pmap->pmap_bits[PG_V_IDX])) !=
2524                     (pmap->pmap_bits[PG_MANAGED_IDX]|pmap->pmap_bits[PG_V_IDX])) {
2525                         kprintf("remove_pte badpte %016lx %016lx %d\n",
2526                                 pte, pv->pv_pindex,
2527                                 pv->pv_pindex < pmap_pt_pindex(0));
2528                 }
2529                 /* PHYS_TO_VM_PAGE() will not work for FICTITIOUS pages */
2530                 /*KKASSERT((pte & (PG_MANAGED|PG_V)) == (PG_MANAGED|PG_V));*/
2531                 if (pte & pmap->pmap_bits[PG_DEVICE_IDX])
2532                         p = pv->pv_m;
2533                 else
2534                         p = PHYS_TO_VM_PAGE(pte & PG_FRAME);
2535                 /* p = pv->pv_m; */
2536
2537                 if (pte & pmap->pmap_bits[PG_M_IDX]) {
2538                         if (pmap_track_modified(ptepindex))
2539                                 vm_page_dirty(p);
2540                 }
2541                 if (pte & pmap->pmap_bits[PG_A_IDX]) {
2542                         vm_page_flag_set(p, PG_REFERENCED);
2543                 }
2544                 if (pte & pmap->pmap_bits[PG_W_IDX])
2545                         atomic_add_long(&pmap->pm_stats.wired_count, -1);
2546                 if (pte & pmap->pmap_bits[PG_G_IDX])
2547                         cpu_invlpg((void *)va);
2548         }
2549
2550         /*
2551          * Unwire the parent page table page.  The wire_count cannot go below
2552          * 1 here because the parent page table page is itself still mapped.
2553          *
2554          * XXX remove the assertions later.
2555          */
2556         KKASSERT(pv->pv_m == p);
2557         if (pvp && vm_page_unwire_quick(pvp->pv_m))
2558                 panic("pmap_remove_pv_pte: Insufficient wire_count");
2559
2560         if (gotpvp)
2561                 pv_put(pvp);
2562 }
2563
2564 /*
2565  * Remove the vm_page association to a pv.  The pv must be locked.
2566  */
2567 static
2568 vm_page_t
2569 pmap_remove_pv_page(pv_entry_t pv)
2570 {
2571         vm_page_t m;
2572
2573         m = pv->pv_m;
2574         KKASSERT(m);
2575         vm_page_spin_lock(m);
2576         pv->pv_m = NULL;
2577         TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
2578         pmap_page_stats_deleting(m);
2579         /*
2580         if (m->object)
2581                 atomic_add_int(&m->object->agg_pv_list_count, -1);
2582         */
2583         if (TAILQ_EMPTY(&m->md.pv_list))
2584                 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
2585         vm_page_spin_unlock(m);
2586         return(m);
2587 }
2588
2589 /*
2590  * Grow the number of kernel page table entries, if needed.
2591  *
2592  * This routine is always called to validate any address space
2593  * beyond KERNBASE (for kldloads).  kernel_vm_end only governs the address
2594  * space below KERNBASE.
2595  */
2596 void
2597 pmap_growkernel(vm_offset_t kstart, vm_offset_t kend)
2598 {
2599         vm_paddr_t paddr;
2600         vm_offset_t ptppaddr;
2601         vm_page_t nkpg;
2602         pd_entry_t *pt, newpt;
2603         pdp_entry_t newpd;
2604         int update_kernel_vm_end;
2605
2606         /*
2607          * bootstrap kernel_vm_end on first real VM use
2608          */
2609         if (kernel_vm_end == 0) {
2610                 kernel_vm_end = VM_MIN_KERNEL_ADDRESS;
2611                 nkpt = 0;
2612                 while ((*pmap_pt(&kernel_pmap, kernel_vm_end) & kernel_pmap.pmap_bits[PG_V_IDX]) != 0) {
2613                         kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) &
2614                                         ~(PAGE_SIZE * NPTEPG - 1);
2615                         nkpt++;
2616                         if (kernel_vm_end - 1 >= kernel_map.max_offset) {
2617                                 kernel_vm_end = kernel_map.max_offset;
2618                                 break;                       
2619                         }
2620                 }
2621         }
2622
2623         /*
2624          * Fill in the gaps.  kernel_vm_end is only adjusted for ranges
2625          * below KERNBASE.  Ranges above KERNBASE are kldloaded and we
2626          * do not want to force-fill 128G worth of page tables.
2627          */
2628         if (kstart < KERNBASE) {
2629                 if (kstart > kernel_vm_end)
2630                         kstart = kernel_vm_end;
2631                 KKASSERT(kend <= KERNBASE);
2632                 update_kernel_vm_end = 1;
2633         } else {
2634                 update_kernel_vm_end = 0;
2635         }
2636
2637         kstart = rounddown2(kstart, PAGE_SIZE * NPTEPG);
2638         kend = roundup2(kend, PAGE_SIZE * NPTEPG);
2639
2640         if (kend - 1 >= kernel_map.max_offset)
2641                 kend = kernel_map.max_offset;
2642
2643         while (kstart < kend) {
2644                 pt = pmap_pt(&kernel_pmap, kstart);
2645                 if (pt == NULL) {
2646                         /* We need a new PDP entry */
2647                         nkpg = vm_page_alloc(NULL, nkpt,
2648                                              VM_ALLOC_NORMAL |
2649                                              VM_ALLOC_SYSTEM |
2650                                              VM_ALLOC_INTERRUPT);
2651                         if (nkpg == NULL) {
2652                                 panic("pmap_growkernel: no memory to grow "
2653                                       "kernel");
2654                         }
2655                         paddr = VM_PAGE_TO_PHYS(nkpg);
2656                         if ((nkpg->flags & PG_ZERO) == 0)
2657                                 pmap_zero_page(paddr);
2658                         vm_page_flag_clear(nkpg, PG_ZERO);
2659                         newpd = (pdp_entry_t)
2660                             (paddr |
2661                             kernel_pmap.pmap_bits[PG_V_IDX] |
2662                             kernel_pmap.pmap_bits[PG_RW_IDX] |
2663                             kernel_pmap.pmap_bits[PG_A_IDX] |
2664                             kernel_pmap.pmap_bits[PG_M_IDX]);
2665                         *pmap_pd(&kernel_pmap, kstart) = newpd;
2666                         nkpt++;
2667                         continue; /* try again */
2668                 }
2669                 if ((*pt & kernel_pmap.pmap_bits[PG_V_IDX]) != 0) {
2670                         kstart = (kstart + PAGE_SIZE * NPTEPG) &
2671                                  ~(PAGE_SIZE * NPTEPG - 1);
2672                         if (kstart - 1 >= kernel_map.max_offset) {
2673                                 kstart = kernel_map.max_offset;
2674                                 break;                       
2675                         }
2676                         continue;
2677                 }
2678
2679                 /*
2680                  * This index is bogus, but out of the way
2681                  */
2682                 nkpg = vm_page_alloc(NULL, nkpt,
2683                                      VM_ALLOC_NORMAL |
2684                                      VM_ALLOC_SYSTEM |
2685                                      VM_ALLOC_INTERRUPT);
2686                 if (nkpg == NULL)
2687                         panic("pmap_growkernel: no memory to grow kernel");
2688
2689                 vm_page_wire(nkpg);
2690                 ptppaddr = VM_PAGE_TO_PHYS(nkpg);
2691                 pmap_zero_page(ptppaddr);
2692                 vm_page_flag_clear(nkpg, PG_ZERO);
2693                 newpt = (pd_entry_t) (ptppaddr |
2694                     kernel_pmap.pmap_bits[PG_V_IDX] |
2695                     kernel_pmap.pmap_bits[PG_RW_IDX] |
2696                     kernel_pmap.pmap_bits[PG_A_IDX] |
2697                     kernel_pmap.pmap_bits[PG_M_IDX]);
2698                 *pmap_pt(&kernel_pmap, kstart) = newpt;
2699                 nkpt++;
2700
2701                 kstart = (kstart + PAGE_SIZE * NPTEPG) &
2702                           ~(PAGE_SIZE * NPTEPG - 1);
2703
2704                 if (kstart - 1 >= kernel_map.max_offset) {
2705                         kstart = kernel_map.max_offset;
2706                         break;                       
2707                 }
2708         }
2709
2710         /*
2711          * Only update kernel_vm_end for areas below KERNBASE.
2712          */
2713         if (update_kernel_vm_end && kernel_vm_end < kstart)
2714                 kernel_vm_end = kstart;
2715 }
2716
2717 /*
2718  *      Add a reference to the specified pmap.
2719  */
2720 void
2721 pmap_reference(pmap_t pmap)
2722 {
2723         if (pmap != NULL) {
2724                 lwkt_gettoken(&pmap->pm_token);
2725                 ++pmap->pm_count;
2726                 lwkt_reltoken(&pmap->pm_token);
2727         }
2728 }
2729
2730 /***************************************************
2731  * page management routines.
2732  ***************************************************/
2733
2734 /*
2735  * Hold a pv without locking it
2736  */
2737 static void
2738 pv_hold(pv_entry_t pv)
2739 {
2740         atomic_add_int(&pv->pv_hold, 1);
2741 }
2742
2743 /*
2744  * Hold a pv_entry, preventing its destruction.  TRUE is returned if the pv
2745  * was successfully locked, FALSE if it wasn't.  The caller must dispose of
2746  * the pv properly.
2747  *
2748  * Either the pmap->pm_spin or the related vm_page_spin (if traversing a
2749  * pv list via its page) must be held by the caller.
2750  */
2751 static int
2752 _pv_hold_try(pv_entry_t pv PMAP_DEBUG_DECL)
2753 {
2754         u_int count;
2755
2756         /*
2757          * Critical path shortcut expects pv to already have one ref
2758          * (for the pv->pv_pmap).
2759          */
2760         if (atomic_cmpset_int(&pv->pv_hold, 1, PV_HOLD_LOCKED | 2)) {
2761 #ifdef PMAP_DEBUG
2762                 pv->pv_func = func;
2763                 pv->pv_line = lineno;
2764 #endif
2765                 return TRUE;
2766         }
2767
2768         for (;;) {
2769                 count = pv->pv_hold;
2770                 cpu_ccfence();
2771                 if ((count & PV_HOLD_LOCKED) == 0) {
2772                         if (atomic_cmpset_int(&pv->pv_hold, count,
2773                                               (count + 1) | PV_HOLD_LOCKED)) {
2774 #ifdef PMAP_DEBUG
2775                                 pv->pv_func = func;
2776                                 pv->pv_line = lineno;
2777 #endif
2778                                 return TRUE;
2779                         }
2780                 } else {
2781                         if (atomic_cmpset_int(&pv->pv_hold, count, count + 1))
2782                                 return FALSE;
2783                 }
2784                 /* retry */
2785         }
2786 }
2787
2788 /*
2789  * Drop a previously held pv_entry which could not be locked, allowing its
2790  * destruction.
2791  *
2792  * Must not be called with a spinlock held as we might zfree() the pv if it
2793  * is no longer associated with a pmap and this was the last hold count.
2794  */
2795 static void
2796 pv_drop(pv_entry_t pv)
2797 {
2798         u_int count;
2799
2800         for (;;) {
2801                 count = pv->pv_hold;
2802                 cpu_ccfence();
2803                 KKASSERT((count & PV_HOLD_MASK) > 0);
2804                 KKASSERT((count & (PV_HOLD_LOCKED | PV_HOLD_MASK)) !=
2805                          (PV_HOLD_LOCKED | 1));
2806                 if (atomic_cmpset_int(&pv->pv_hold, count, count - 1)) {
2807                         if ((count & PV_HOLD_MASK) == 1) {
2808                                 KKASSERT(count == 1);
2809                                 KKASSERT(pv->pv_pmap == NULL);
2810                                 zfree(pvzone, pv);
2811                         }
2812                         return;
2813                 }
2814                 /* retry */
2815         }
2816 }
2817
2818 /*
2819  * Find or allocate the requested PV entry, returning a locked, held pv.
2820  *
2821  * If (*isnew) is non-zero, the returned pv will have two hold counts, one
2822  * for the caller and one representing the pmap and vm_page association.
2823  *
2824  * If (*isnew) is zero, the returned pv will have only one hold count.
2825  *
2826  * Since both associations can only be adjusted while the pv is locked,
2827  * together they represent just one additional hold.
2828  */
2829 static
2830 pv_entry_t
2831 _pv_alloc(pmap_t pmap, vm_pindex_t pindex, int *isnew PMAP_DEBUG_DECL)
2832 {
2833         pv_entry_t pv;
2834         pv_entry_t pnew = NULL;
2835
2836         spin_lock(&pmap->pm_spin);
2837         for (;;) {
2838                 if ((pv = pmap->pm_pvhint) == NULL || pv->pv_pindex != pindex) {
2839                         pv = pv_entry_rb_tree_RB_LOOKUP(&pmap->pm_pvroot,
2840                                                         pindex);
2841                 }
2842                 if (pv == NULL) {
2843                         if (pnew == NULL) {
2844                                 spin_unlock(&pmap->pm_spin);
2845                                 pnew = zalloc(pvzone);
2846                                 spin_lock(&pmap->pm_spin);
2847                                 continue;
2848                         }
2849                         pnew->pv_pmap = pmap;
2850                         pnew->pv_pindex = pindex;
2851                         pnew->pv_hold = PV_HOLD_LOCKED | 2;
2852 #ifdef PMAP_DEBUG
2853                         pnew->pv_func = func;
2854                         pnew->pv_line = lineno;
2855 #endif
2856                         pv_entry_rb_tree_RB_INSERT(&pmap->pm_pvroot, pnew);
2857                         ++pmap->pm_generation;
2858                         atomic_add_long(&pmap->pm_stats.resident_count, 1);
2859                         spin_unlock(&pmap->pm_spin);
2860                         *isnew = 1;
2861                         return(pnew);
2862                 }
2863                 if (pnew) {
2864                         spin_unlock(&pmap->pm_spin);
2865                         zfree(pvzone, pnew);
2866                         pnew = NULL;
2867                         spin_lock(&pmap->pm_spin);
2868                         continue;
2869                 }
2870                 if (_pv_hold_try(pv PMAP_DEBUG_COPY)) {
2871                         spin_unlock(&pmap->pm_spin);
2872                 } else {
2873                         spin_unlock(&pmap->pm_spin);
2874                         _pv_lock(pv PMAP_DEBUG_COPY);
2875                 }
2876                 if (pv->pv_pmap == pmap && pv->pv_pindex == pindex) {
2877                         *isnew = 0;
2878                         return(pv);
2879                 }
2880                 pv_put(pv);
2881                 spin_lock(&pmap->pm_spin);
2882         }
2883 }
2884
2885 /*
2886  * Find the requested PV entry, returning a locked+held pv or NULL
2887  */
2888 static
2889 pv_entry_t
2890 _pv_get(pmap_t pmap, vm_pindex_t pindex PMAP_DEBUG_DECL)
2891 {
2892         pv_entry_t pv;
2893
2894         spin_lock(&pmap->pm_spin);
2895         for (;;) {
2896                 /*
2897                  * Shortcut cache
2898                  */
2899                 if ((pv = pmap->pm_pvhint) == NULL || pv->pv_pindex != pindex) {
2900                         pv = pv_entry_rb_tree_RB_LOOKUP(&pmap->pm_pvroot,
2901                                                         pindex);
2902                 }
2903                 if (pv == NULL) {
2904                         spin_unlock(&pmap->pm_spin);
2905                         return NULL;
2906                 }
2907                 if (_pv_hold_try(pv PMAP_DEBUG_COPY)) {
2908                         spin_unlock(&pmap->pm_spin);
2909                 } else {
2910                         spin_unlock(&pmap->pm_spin);
2911                         _pv_lock(pv PMAP_DEBUG_COPY);
2912                 }
2913                 if (pv->pv_pmap == pmap && pv->pv_pindex == pindex) {
2914                         pv_cache(pv, pindex);
2915                         return(pv);
2916                 }
2917                 pv_put(pv);
2918                 spin_lock(&pmap->pm_spin);
2919         }
2920 }
2921
2922 /*
2923  * Lookup, hold, and attempt to lock (pmap,pindex).
2924  *
2925  * If the entry does not exist NULL is returned and *errorp is set to 0
2926  *
2927  * If the entry exists and could be successfully locked it is returned and
2928  * errorp is set to 0.
2929  *
2930  * If the entry exists but could NOT be successfully locked it is returned
2931  * held and *errorp is set to 1.
2932  */
2933 static
2934 pv_entry_t
2935 pv_get_try(pmap_t pmap, vm_pindex_t pindex, int *errorp)
2936 {
2937         pv_entry_t pv;
2938
2939         spin_lock_shared(&pmap->pm_spin);
2940         if ((pv = pmap->pm_pvhint) == NULL || pv->pv_pindex != pindex)
2941                 pv = pv_entry_rb_tree_RB_LOOKUP(&pmap->pm_pvroot, pindex);
2942         if (pv == NULL) {
2943                 spin_unlock_shared(&pmap->pm_spin);
2944                 *errorp = 0;
2945                 return NULL;
2946         }
2947         if (pv_hold_try(pv)) {
2948                 pv_cache(pv, pindex);
2949                 spin_unlock_shared(&pmap->pm_spin);
2950                 *errorp = 0;
2951                 KKASSERT(pv->pv_pmap == pmap && pv->pv_pindex == pindex);
2952                 return(pv);     /* lock succeeded */
2953         }
2954         spin_unlock_shared(&pmap->pm_spin);
2955         *errorp = 1;
2956         return (pv);            /* lock failed */
2957 }
2958
2959 /*
2960  * Find the requested PV entry, returning a held pv or NULL
2961  */
2962 static
2963 pv_entry_t
2964 pv_find(pmap_t pmap, vm_pindex_t pindex)
2965 {
2966         pv_entry_t pv;
2967
2968         spin_lock_shared(&pmap->pm_spin);
2969
2970         if ((pv = pmap->pm_pvhint) == NULL || pv->pv_pindex != pindex)
2971                 pv = pv_entry_rb_tree_RB_LOOKUP(&pmap->pm_pvroot, pindex);
2972         if (pv == NULL) {
2973                 spin_unlock_shared(&pmap->pm_spin);
2974                 return NULL;
2975         }
2976         pv_hold(pv);
2977         pv_cache(pv, pindex);
2978         spin_unlock_shared(&pmap->pm_spin);
2979         return(pv);
2980 }
2981
2982 /*
2983  * Lock a held pv, keeping the hold count
2984  */
2985 static
2986 void
2987 _pv_lock(pv_entry_t pv PMAP_DEBUG_DECL)
2988 {
2989         u_int count;
2990
2991         for (;;) {
2992                 count = pv->pv_hold;
2993                 cpu_ccfence();
2994                 if ((count & PV_HOLD_LOCKED) == 0) {
2995                         if (atomic_cmpset_int(&pv->pv_hold, count,
2996                                               count | PV_HOLD_LOCKED)) {
2997 #ifdef PMAP_DEBUG
2998                                 pv->pv_func = func;
2999                                 pv->pv_line = lineno;
3000 #endif
3001                                 return;
3002                         }
3003                         continue;
3004                 }
3005                 tsleep_interlock(pv, 0);
3006                 if (atomic_cmpset_int(&pv->pv_hold, count,
3007                                       count | PV_HOLD_WAITING)) {
3008 #ifdef PMAP_DEBUG
3009                         kprintf("pv waiting on %s:%d\n",
3010                                         pv->pv_func, pv->pv_line);
3011 #endif
3012                         tsleep(pv, PINTERLOCKED, "pvwait", hz);
3013                 }
3014                 /* retry */
3015         }
3016 }
3017
3018 /*
3019  * Unlock a held and locked pv, keeping the hold count.
3020  */
3021 static
3022 void
3023 pv_unlock(pv_entry_t pv)
3024 {
3025         u_int count;
3026
3027         for (;;) {
3028                 count = pv->pv_hold;
3029                 cpu_ccfence();
3030                 KKASSERT((count & (PV_HOLD_LOCKED | PV_HOLD_MASK)) >=
3031                          (PV_HOLD_LOCKED | 1));
3032                 if (atomic_cmpset_int(&pv->pv_hold, count,
3033                                       count &
3034                                       ~(PV_HOLD_LOCKED | PV_HOLD_WAITING))) {
3035                         if (count & PV_HOLD_WAITING)
3036                                 wakeup(pv);
3037                         break;
3038                 }
3039         }
3040 }
3041
3042 /*
3043  * Unlock and drop a pv.  If the pv is no longer associated with a pmap
3044  * and the hold count drops to zero we will free it.
3045  *
3046  * Caller should not hold any spin locks.  We are protected from hold races
3047  * by virtue of holds only occuring only with a pmap_spin or vm_page_spin
3048  * lock held.  A pv cannot be located otherwise.
3049  */
3050 static
3051 void
3052 pv_put(pv_entry_t pv)
3053 {
3054         /*
3055          * Fast - shortcut most common condition
3056          */
3057         if (atomic_cmpset_int(&pv->pv_hold, PV_HOLD_LOCKED | 2, 1))
3058                 return;
3059
3060         /*
3061          * Slow
3062          */
3063         pv_unlock(pv);
3064         pv_drop(pv);
3065 }
3066
3067 /*
3068  * Remove the pmap association from a pv, require that pv_m already be removed,
3069  * then unlock and drop the pv.  Any pte operations must have already been
3070  * completed.  This call may result in a last-drop which will physically free
3071  * the pv.
3072  *
3073  * Removing the pmap association entails an additional drop.
3074  *
3075  * pv must be exclusively locked on call and will be disposed of on return.
3076  */
3077 static
3078 void
3079 pv_free(pv_entry_t pv)
3080 {
3081         pmap_t pmap;
3082
3083         KKASSERT(pv->pv_m == NULL);
3084         KKASSERT((pv->pv_hold & PV_HOLD_MASK) >= 2);
3085         if ((pmap = pv->pv_pmap) != NULL) {
3086                 spin_lock(&pmap->pm_spin);
3087                 pv_entry_rb_tree_RB_REMOVE(&pmap->pm_pvroot, pv);
3088                 ++pmap->pm_generation;
3089                 if (pmap->pm_pvhint == pv)
3090                         pmap->pm_pvhint = NULL;
3091                 atomic_add_long(&pmap->pm_stats.resident_count, -1);
3092                 pv->pv_pmap = NULL;
3093                 pv->pv_pindex = 0;
3094                 spin_unlock(&pmap->pm_spin);
3095
3096                 /*
3097                  * Try to shortcut three atomic ops, otherwise fall through
3098                  * and do it normally.  Drop two refs and the lock all in
3099                  * one go.
3100                  */
3101                 if (atomic_cmpset_int(&pv->pv_hold, PV_HOLD_LOCKED | 2, 0)) {
3102                         zfree(pvzone, pv);
3103                         return;
3104                 }
3105                 pv_drop(pv);    /* ref for pv_pmap */
3106         }
3107         pv_put(pv);
3108 }
3109
3110 /*
3111  * This routine is very drastic, but can save the system
3112  * in a pinch.
3113  */
3114 void
3115 pmap_collect(void)
3116 {
3117         int i;
3118         vm_page_t m;
3119         static int warningdone=0;
3120
3121         if (pmap_pagedaemon_waken == 0)
3122                 return;
3123         pmap_pagedaemon_waken = 0;
3124         if (warningdone < 5) {
3125                 kprintf("pmap_collect: collecting pv entries -- "
3126                         "suggest increasing PMAP_SHPGPERPROC\n");
3127                 warningdone++;
3128         }
3129
3130         for (i = 0; i < vm_page_array_size; i++) {
3131                 m = &vm_page_array[i];
3132                 if (m->wire_count || m->hold_count)
3133                         continue;
3134                 if (vm_page_busy_try(m, TRUE) == 0) {
3135                         if (m->wire_count == 0 && m->hold_count == 0) {
3136                                 pmap_remove_all(m);
3137                         }
3138                         vm_page_wakeup(m);
3139                 }
3140         }
3141 }
3142
3143 /*
3144  * Scan the pmap for active page table entries and issue a callback.
3145  * The callback must dispose of pte_pv, whos PTE entry is at *ptep in
3146  * its parent page table.
3147  *
3148  * pte_pv will be NULL if the page or page table is unmanaged.
3149  * pt_pv will point to the page table page containing the pte for the page.
3150  *
3151  * NOTE! If we come across an unmanaged page TABLE (verses an unmanaged page),
3152  *       we pass a NULL pte_pv and we pass a pt_pv pointing to the passed
3153  *       process pmap's PD and page to the callback function.  This can be
3154  *       confusing because the pt_pv is really a pd_pv, and the target page
3155  *       table page is simply aliased by the pmap and not owned by it.
3156  *
3157  * It is assumed that the start and end are properly rounded to the page size.
3158  *
3159  * It is assumed that PD pages and above are managed and thus in the RB tree,
3160  * allowing us to use RB_SCAN from the PD pages down for ranged scans.
3161  */
3162 struct pmap_scan_info {
3163         struct pmap *pmap;
3164         vm_offset_t sva;
3165         vm_offset_t eva;
3166         vm_pindex_t sva_pd_pindex;
3167         vm_pindex_t eva_pd_pindex;
3168         void (*func)(pmap_t, struct pmap_scan_info *,
3169                      pv_entry_t, pv_entry_t, int, vm_offset_t,
3170                      pt_entry_t *, void *);
3171         void *arg;
3172         int doinval;
3173         struct pmap_inval_info inval;
3174 };
3175
3176 static int pmap_scan_cmp(pv_entry_t pv, void *data);
3177 static int pmap_scan_callback(pv_entry_t pv, void *data);
3178
3179 static void
3180 pmap_scan(struct pmap_scan_info *info)
3181 {
3182         struct pmap *pmap = info->pmap;
3183         pv_entry_t pd_pv;       /* A page directory PV */
3184         pv_entry_t pt_pv;       /* A page table PV */
3185         pv_entry_t pte_pv;      /* A page table entry PV */
3186         pt_entry_t *ptep;
3187         pt_entry_t oldpte;
3188         struct pv_entry dummy_pv;
3189         int generation;
3190
3191         if (pmap == NULL)
3192                 return;
3193
3194         /*
3195          * Hold the token for stability; if the pmap is empty we have nothing
3196          * to do.
3197          */
3198         lwkt_gettoken(&pmap->pm_token);
3199 #if 0
3200         if (pmap->pm_stats.resident_count == 0) {
3201                 lwkt_reltoken(&pmap->pm_token);
3202                 return;
3203         }
3204 #endif
3205
3206         pmap_inval_init(&info->inval);
3207
3208 again:
3209         /*
3210          * Special handling for scanning one page, which is a very common
3211          * operation (it is?).
3212          *
3213          * NOTE: Locks must be ordered bottom-up. pte,pt,pd,pdp,pml4
3214          */
3215         if (info->sva + PAGE_SIZE == info->eva) {
3216                 generation = pmap->pm_generation;
3217                 if (info->sva >= VM_MAX_USER_ADDRESS) {
3218                         /*
3219                          * Kernel mappings do not track wire counts on
3220                          * page table pages and only maintain pd_pv and
3221                          * pte_pv levels so pmap_scan() works.
3222                          */
3223                         pt_pv = NULL;
3224                         pte_pv = pv_get(pmap, pmap_pte_pindex(info->sva));
3225                         ptep = vtopte(info->sva);
3226                 } else {
3227                         /*
3228                          * User pages which are unmanaged will not have a
3229                          * pte_pv.  User page table pages which are unmanaged
3230                          * (shared from elsewhere) will also not have a pt_pv.
3231                          * The func() callback will pass both pte_pv and pt_pv
3232                          * as NULL in that case.
3233                          */
3234                         pte_pv = pv_get(pmap, pmap_pte_pindex(info->sva));
3235                         pt_pv = pv_get(pmap, pmap_pt_pindex(info->sva));
3236                         if (pt_pv == NULL) {
3237                                 KKASSERT(pte_pv == NULL);
3238                                 pd_pv = pv_get(pmap, pmap_pd_pindex(info->sva));
3239                                 if (pd_pv) {
3240                                         ptep = pv_pte_lookup(pd_pv,
3241                                                     pmap_pt_index(info->sva));
3242                                         if (*ptep) {
3243                                                 info->func(pmap, info,
3244                                                      NULL, pd_pv, 1,
3245                                                      info->sva, ptep,
3246                                                      info->arg);
3247                                         }
3248                                         pv_put(pd_pv);
3249                                 }
3250                                 goto fast_skip;
3251                         }
3252                         ptep = pv_pte_lookup(pt_pv, pmap_pte_index(info->sva));
3253                 }
3254
3255                 /*
3256                  * NOTE: *ptep can't be ripped out from under us if we hold
3257                  *       pte_pv locked, but bits can change.  However, there is
3258                  *       a race where another thread may be inserting pte_pv
3259                  *       and setting *ptep just after our pte_pv lookup fails.
3260                  *
3261                  *       In this situation we can end up with a NULL pte_pv
3262                  *       but find that we have a managed *ptep.  We explicitly
3263                  *       check for this race.
3264                  */
3265                 oldpte = *ptep;
3266                 cpu_ccfence();
3267                 if (oldpte == 0) {
3268                         /*
3269                          * Unlike the pv_find() case below we actually
3270                          * acquired a locked pv in this case so any
3271                          * race should have been resolved.  It is expected
3272                          * to not exist.
3273                          */
3274                         KKASSERT(pte_pv == NULL);
3275                 } else if (pte_pv) {
3276                         KASSERT((oldpte & (pmap->pmap_bits[PG_MANAGED_IDX] |
3277                                            pmap->pmap_bits[PG_V_IDX])) ==
3278                                 (pmap->pmap_bits[PG_MANAGED_IDX] |
3279                                  pmap->pmap_bits[PG_V_IDX]),
3280                             ("badA *ptep %016lx/%016lx sva %016lx pte_pv %p"
3281                              "generation %d/%d",
3282                             *ptep, oldpte, info->sva, pte_pv,
3283                             generation, pmap->pm_generation));
3284                         info->func(pmap, info, pte_pv, pt_pv, 0,
3285                                    info->sva, ptep, info->arg);
3286                 } else {
3287                         /*
3288                          * Check for insertion race
3289                          */
3290                         if ((oldpte & pmap->pmap_bits[PG_MANAGED_IDX]) &&
3291                             pt_pv) {
3292                                 pte_pv = pv_find(pmap,
3293                                                  pmap_pte_pindex(info->sva));
3294                                 if (pte_pv) {
3295                                         pv_drop(pte_pv);
3296                                         pv_put(pt_pv);
3297                                         kprintf("pmap_scan: RACE1 "
3298                                                 "%016jx, %016lx\n",
3299                                                 info->sva, oldpte);
3300                                         goto again;
3301                                 }
3302                         }
3303
3304                         /*
3305                          * Didn't race
3306                          */
3307                         KASSERT((oldpte & (pmap->pmap_bits[PG_MANAGED_IDX] |
3308                                            pmap->pmap_bits[PG_V_IDX])) ==
3309                             pmap->pmap_bits[PG_V_IDX],
3310                             ("badB *ptep %016lx/%016lx sva %016lx pte_pv NULL"
3311                              "generation %d/%d",
3312                             *ptep, oldpte, info->sva,
3313                             generation, pmap->pm_generation));
3314                         info->func(pmap, info, NULL, pt_pv, 0,
3315                             info->sva, ptep, info->arg);
3316                 }
3317                 if (pt_pv)
3318                         pv_put(pt_pv);
3319 fast_skip:
3320                 pmap_inval_done(&info->inval);
3321                 lwkt_reltoken(&pmap->pm_token);
3322                 return;
3323         }
3324
3325         /*
3326          * Nominal scan case, RB_SCAN() for PD pages and iterate from
3327          * there.
3328          */
3329         info->sva_pd_pindex = pmap_pd_pindex(info->sva);
3330         info->eva_pd_pindex = pmap_pd_pindex(info->eva + NBPDP - 1);
3331
3332         if (info->sva >= VM_MAX_USER_ADDRESS) {
3333                 /*
3334                  * The kernel does not currently maintain any pv_entry's for
3335                  * higher-level page tables.
3336                  */
3337                 bzero(&dummy_pv, sizeof(dummy_pv));
3338                 dummy_pv.pv_pindex = info->sva_pd_pindex;
3339                 spin_lock(&pmap->pm_spin);
3340                 while (dummy_pv.pv_pindex < info->eva_pd_pindex) {
3341                         pmap_scan_callback(&dummy_pv, info);
3342                         ++dummy_pv.pv_pindex;
3343                 }
3344                 spin_unlock(&pmap->pm_spin);
3345         } else {
3346                 /*
3347                  * User page tables maintain local PML4, PDP, and PD
3348                  * pv_entry's at the very least.  PT pv's might be
3349                  * unmanaged and thus not exist.  PTE pv's might be
3350                  * unmanaged and thus not exist.
3351                  */
3352                 spin_lock(&pmap->pm_spin);
3353                 pv_entry_rb_tree_RB_SCAN(&pmap->pm_pvroot,
3354                         pmap_scan_cmp, pmap_scan_callback, info);
3355                 spin_unlock(&pmap->pm_spin);
3356         }
3357         pmap_inval_done(&info->inval);
3358         lwkt_reltoken(&pmap->pm_token);
3359 }
3360
3361 /*
3362  * WARNING! pmap->pm_spin held
3363  */
3364 static int
3365 pmap_scan_cmp(pv_entry_t pv, void *data)
3366 {
3367         struct pmap_scan_info *info = data;
3368         if (pv->pv_pindex < info->sva_pd_pindex)
3369                 return(-1);
3370         if (pv->pv_pindex >= info->eva_pd_pindex)
3371                 return(1);
3372         return(0);
3373 }
3374
3375 /*
3376  * WARNING! pmap->pm_spin held
3377  */
3378 static int
3379 pmap_scan_callback(pv_entry_t pv, void *data)
3380 {
3381         struct pmap_scan_info *info = data;
3382         struct pmap *pmap = info->pmap;
3383         pv_entry_t pd_pv;       /* A page directory PV */
3384         pv_entry_t pt_pv;       /* A page table PV */
3385         pv_entry_t pte_pv;      /* A page table entry PV */
3386         pt_entry_t *ptep;
3387         pt_entry_t oldpte;
3388         vm_offset_t sva;
3389         vm_offset_t eva;
3390         vm_offset_t va_next;
3391         vm_pindex_t pd_pindex;
3392         int error;
3393         int generation;
3394
3395         /*
3396          * Pull the PD pindex from the pv before releasing the spinlock.
3397          *
3398          * WARNING: pv is faked for kernel pmap scans.
3399          */
3400         pd_pindex = pv->pv_pindex;
3401         spin_unlock(&pmap->pm_spin);
3402         pv = NULL;      /* invalid after spinlock unlocked */
3403
3404         /*
3405          * Calculate the page range within the PD.  SIMPLE pmaps are
3406          * direct-mapped for the entire 2^64 address space.  Normal pmaps
3407          * reflect the user and kernel address space which requires
3408          * cannonicalization w/regards to converting pd_pindex's back
3409          * into addresses.
3410          */
3411         sva = (pd_pindex - NUPTE_TOTAL - NUPT_TOTAL) << PDPSHIFT;
3412         if ((pmap->pm_flags & PMAP_FLAG_SIMPLE) == 0 &&
3413             (sva & PML4_SIGNMASK)) {
3414                 sva |= PML4_SIGNMASK;
3415         }
3416         eva = sva + NBPDP;      /* can overflow */
3417         if (sva < info->sva)
3418                 sva = info->sva;
3419         if (eva < info->sva || eva > info->eva)
3420                 eva = info->eva;
3421
3422         /*
3423          * NOTE: kernel mappings do not track page table pages, only
3424          *       terminal pages.
3425          *
3426          * NOTE: Locks must be ordered bottom-up. pte,pt,pd,pdp,pml4.
3427          *       However, for the scan to be efficient we try to
3428          *       cache items top-down.
3429          */
3430         pd_pv = NULL;
3431         pt_pv = NULL;
3432
3433         for (; sva < eva; sva = va_next) {
3434                 if (sva >= VM_MAX_USER_ADDRESS) {
3435                         if (pt_pv) {
3436                                 pv_put(pt_pv);
3437                                 pt_pv = NULL;
3438                         }
3439                         goto kernel_skip;
3440                 }
3441
3442                 /*
3443                  * PD cache (degenerate case if we skip).  It is possible
3444                  * for the PD to not exist due to races.  This is ok.
3445                  */
3446                 if (pd_pv == NULL) {
3447                         pd_pv = pv_get(pmap, pmap_pd_pindex(sva));
3448                 } else if (pd_pv->pv_pindex != pmap_pd_pindex(sva)) {
3449                         pv_put(pd_pv);
3450                         pd_pv = pv_get(pmap, pmap_pd_pindex(sva));
3451                 }
3452                 if (pd_pv == NULL) {
3453                         va_next = (sva + NBPDP) & ~PDPMASK;
3454                         if (va_next < sva)
3455                                 va_next = eva;
3456                         continue;
3457                 }
3458
3459                 /*
3460                  * PT cache
3461                  */
3462                 if (pt_pv == NULL) {
3463                         if (pd_pv) {
3464                                 pv_put(pd_pv);
3465                                 pd_pv = NULL;
3466                         }
3467                         pt_pv = pv_get(pmap, pmap_pt_pindex(sva));
3468                 } else if (pt_pv->pv_pindex != pmap_pt_pindex(sva)) {
3469                         if (pd_pv) {
3470                                 pv_put(pd_pv);
3471                                 pd_pv = NULL;
3472                         }
3473                         pv_put(pt_pv);
3474                         pt_pv = pv_get(pmap, pmap_pt_pindex(sva));
3475                 }
3476
3477                 /*
3478                  * If pt_pv is NULL we either have an shared page table
3479                  * page and must issue a callback specific to that case,
3480                  * or there is no page table page.
3481                  *
3482                  * Either way we can skip the page table page.
3483                  */
3484                 if (pt_pv == NULL) {
3485                         /*
3486                          * Possible unmanaged (shared from another pmap)
3487                          * page table page.
3488                          */
3489                         if (pd_pv == NULL)
3490                                 pd_pv = pv_get(pmap, pmap_pd_pindex(sva));
3491                         KKASSERT(pd_pv != NULL);
3492                         ptep = pv_pte_lookup(pd_pv, pmap_pt_index(sva));
3493                         if (*ptep & pmap->pmap_bits[PG_V_IDX]) {
3494                                 info->func(pmap, info, NULL, pd_pv, 1,
3495                                            sva, ptep, info->arg);
3496                         }
3497
3498                         /*
3499                          * Done, move to next page table page.
3500                          */
3501                         va_next = (sva + NBPDR) & ~PDRMASK;
3502                         if (va_next < sva)
3503                                 va_next = eva;
3504                         continue;
3505                 }
3506
3507                 /*
3508                  * From this point in the loop testing pt_pv for non-NULL
3509                  * means we are in UVM, else if it is NULL we are in KVM.
3510                  *
3511                  * Limit our scan to either the end of the va represented
3512                  * by the current page table page, or to the end of the
3513                  * range being removed.
3514                  */
3515 kernel_skip:
3516                 va_next = (sva + NBPDR) & ~PDRMASK;
3517                 if (va_next < sva)
3518                         va_next = eva;
3519                 if (va_next > eva)
3520                         va_next = eva;
3521
3522                 /*
3523                  * Scan the page table for pages.  Some pages may not be
3524                  * managed (might not have a pv_entry).
3525                  *
3526                  * There is no page table management for kernel pages so
3527                  * pt_pv will be NULL in that case, but otherwise pt_pv
3528                  * is non-NULL, locked, and referenced.
3529                  */
3530
3531                 /*
3532                  * At this point a non-NULL pt_pv means a UVA, and a NULL
3533                  * pt_pv means a KVA.
3534                  */
3535                 if (pt_pv)
3536                         ptep = pv_pte_lookup(pt_pv, pmap_pte_index(sva));
3537                 else
3538                         ptep = vtopte(sva);
3539
3540                 while (sva < va_next) {
3541                         /*
3542                          * Acquire the related pte_pv, if any.  If *ptep == 0
3543                          * the related pte_pv should not exist, but if *ptep
3544                          * is not zero the pte_pv may or may not exist (e.g.
3545                          * will not exist for an unmanaged page).
3546                          *
3547                          * However a multitude of races are possible here.
3548                          *
3549                          * In addition, the (pt_pv, pte_pv) lock order is
3550                          * backwards, so we have to be careful in aquiring
3551                          * a properly locked pte_pv.
3552                          */
3553                         generation = pmap->pm_generation;
3554                         if (pt_pv) {
3555                                 pte_pv = pv_get_try(pmap, pmap_pte_pindex(sva),
3556                                                     &error);
3557                                 if (error) {
3558                                         if (pd_pv) {
3559                                                 pv_put(pd_pv);
3560                                                 pd_pv = NULL;
3561                                         }
3562                                         pv_put(pt_pv);   /* must be non-NULL */
3563                                         pt_pv = NULL;
3564                                         pv_lock(pte_pv); /* safe to block now */
3565                                         pv_put(pte_pv);
3566                                         pte_pv = NULL;
3567                                         pt_pv = pv_get(pmap,
3568                                                        pmap_pt_pindex(sva));
3569                                         /*
3570                                          * pt_pv reloaded, need new ptep
3571                                          */
3572                                         KKASSERT(pt_pv != NULL);
3573                                         ptep = pv_pte_lookup(pt_pv,
3574                                                         pmap_pte_index(sva));
3575                                         continue;
3576                                 }
3577                         } else {
3578                                 pte_pv = pv_get(pmap, pmap_pte_pindex(sva));
3579                         }
3580
3581                         /*
3582                          * Ok, if *ptep == 0 we had better NOT have a pte_pv.
3583                          */
3584                         oldpte = *ptep;
3585                         if (oldpte == 0) {
3586                                 if (pte_pv) {
3587                                         kprintf("Unexpected non-NULL pte_pv "
3588                                                 "%p pt_pv %p "
3589                                                 "*ptep = %016lx/%016lx\n",
3590                                                 pte_pv, pt_pv, *ptep, oldpte);
3591                                         panic("Unexpected non-NULL pte_pv");
3592                                 }
3593                                 sva += PAGE_SIZE;
3594                                 ++ptep;
3595                                 continue;
3596                         }
3597
3598                         /*
3599                          * Ready for the callback.  The locked pte_pv (if any)
3600                          * is consumed by the callback.  pte_pv will exist if
3601                          *  the page is managed, and will not exist if it
3602                          * isn't.
3603                          */
3604                         if (pte_pv) {
3605                                 KASSERT((oldpte & (pmap->pmap_bits[PG_MANAGED_IDX] | pmap->pmap_bits[PG_V_IDX])) ==
3606                                     (pmap->pmap_bits[PG_MANAGED_IDX] | pmap->pmap_bits[PG_V_IDX]),
3607                                     ("badC *ptep %016lx/%016lx sva %016lx "
3608                                     "pte_pv %p pm_generation %d/%d",
3609                                     *ptep, oldpte, sva, pte_pv,
3610                                     generation, pmap->pm_generation));
3611                                 info->func(pmap, info, pte_pv, pt_pv, 0,
3612                                     sva, ptep, info->arg);
3613                         } else {
3614                                 /*
3615                                  * Check for insertion race.  Since there is no
3616                                  * pte_pv to guard us it is possible for us
3617                                  * to race another thread doing an insertion.
3618                                  * Our lookup misses the pte_pv but our *ptep
3619                                  * check sees the inserted pte.
3620                                  *
3621                                  * XXX panic case seems to occur within a
3622                                  * vm_fork() of /bin/sh, which frankly
3623                                  * shouldn't happen since no other threads
3624                                  * should be inserting to our pmap in that
3625                                  * situation.  Removing, possibly.  Inserting,
3626                                  * shouldn't happen.
3627                                  */
3628                                 if ((oldpte & pmap->pmap_bits[PG_MANAGED_IDX]) &&
3629                                     pt_pv) {
3630                                         pte_pv = pv_find(pmap,
3631                                                          pmap_pte_pindex(sva));
3632                                         if (pte_pv) {
3633                                                 pv_drop(pte_pv);
3634                                                 kprintf("pmap_scan: RACE2 "
3635                                                         "%016jx, %016lx\n",
3636                                                         sva, oldpte);
3637                                                 continue;
3638                                         }
3639                                 }
3640
3641                                 /*
3642                                  * Didn't race
3643                                  */
3644                                 KASSERT((oldpte & (pmap->pmap_bits[PG_MANAGED_IDX] | pmap->pmap_bits[PG_V_IDX])) ==
3645                                     pmap->pmap_bits[PG_V_IDX],
3646                                     ("badD *ptep %016lx/%016lx sva %016lx "
3647                                     "pte_pv NULL pm_generation %d/%d",
3648                                      *ptep, oldpte, sva,
3649                                      generation, pmap->pm_generation));
3650                                 info->func(pmap, info, NULL, pt_pv, 0,
3651                                     sva, ptep, info->arg);
3652                         }
3653                         pte_pv = NULL;
3654                         sva += PAGE_SIZE;
3655                         ++ptep;
3656                 }
3657                 lwkt_yield();
3658         }
3659         if (pd_pv) {
3660                 pv_put(pd_pv);
3661                 pd_pv = NULL;
3662         }
3663         if (pt_pv) {
3664                 pv_put(pt_pv);
3665                 pt_pv = NULL;
3666         }
3667         lwkt_yield();
3668
3669         /*
3670          * Relock before returning.
3671          */
3672         spin_lock(&pmap->pm_spin);
3673         return (0);
3674 }
3675
3676 void
3677 pmap_remove(struct pmap *pmap, vm_offset_t sva, vm_offset_t eva)
3678 {
3679         struct pmap_scan_info info;
3680
3681         info.pmap = pmap;
3682         info.sva = sva;
3683         info.eva = eva;
3684         info.func = pmap_remove_callback;
3685         info.arg = NULL;
3686         info.doinval = 1;       /* normal remove requires pmap inval */
3687         pmap_scan(&info);
3688 }
3689
3690 static void
3691 pmap_remove_noinval(struct pmap *pmap, vm_offset_t sva, vm_offset_t eva)
3692 {
3693         struct pmap_scan_info info;
3694
3695         info.pmap = pmap;
3696         info.sva = sva;
3697         info.eva = eva;
3698         info.func = pmap_remove_callback;
3699         info.arg = NULL;
3700         info.doinval = 0;       /* normal remove requires pmap inval */
3701         pmap_scan(&info);
3702 }
3703
3704 static void
3705 pmap_remove_callback(pmap_t pmap, struct pmap_scan_info *info,
3706                      pv_entry_t pte_pv, pv_entry_t pt_pv, int sharept,
3707                      vm_offset_t va, pt_entry_t *ptep, void *arg __unused)
3708 {
3709         pt_entry_t pte;
3710
3711         if (pte_pv) {
3712                 /*
3713                  * This will also drop pt_pv's wire_count. Note that
3714                  * terminal pages are not wired based on mmu presence.
3715                  */
3716                 if (info->doinval)
3717                         pmap_remove_pv_pte(pte_pv, pt_pv, &info->inval);
3718                 else
3719                         pmap_remove_pv_pte(pte_pv, pt_pv, NULL);
3720                 pmap_remove_pv_page(pte_pv);
3721                 pv_free(pte_pv);
3722         } else if (sharept == 0) {
3723                 /*
3724                  * Unmanaged page
3725                  *
3726                  * pt_pv's wire_count is still bumped by unmanaged pages
3727                  * so we must decrement it manually.
3728                  */
3729                 if (info->doinval)
3730                         pmap_inval_interlock(&info->inval, pmap, va);
3731                 pte = pte_load_clear(ptep);
3732                 if (info->doinval)
3733                         pmap_inval_deinterlock(&info->inval, pmap);
3734                 if (pte & pmap->pmap_bits[PG_W_IDX])
3735                         atomic_add_long(&pmap->pm_stats.wired_count, -1);
3736                 atomic_add_long(&pmap->pm_stats.resident_count, -1);
3737                 if (vm_page_unwire_quick(pt_pv->pv_m))
3738                         panic("pmap_remove: insufficient wirecount");
3739         } else {
3740                 /*
3741                  * Unmanaged page table, pt_pv is actually the pd_pv
3742                  * for our pmap (not the share object pmap).
3743                  *
3744                  * We have to unwire the target page table page and we
3745                  * have to unwire our page directory page.
3746                  */
3747                 if (info->doinval)
3748                         pmap_inval_interlock(&info->inval, pmap, va);
3749                 pte = pte_load_clear(ptep);
3750                 if (info->doinval)
3751                         pmap_inval_deinterlock(&info->inval, pmap);
3752                 atomic_add_long(&pmap->pm_stats.resident_count, -1);
3753                 KKASSERT((pte & pmap->pmap_bits[PG_DEVICE_IDX]) == 0);
3754                 if (vm_page_unwire_quick(PHYS_TO_VM_PAGE(pte & PG_FRAME)))
3755                         panic("pmap_remove: shared pgtable1 bad wirecount");
3756                 if (vm_page_unwire_quick(pt_pv->pv_m))
3757                         panic("pmap_remove: shared pgtable2 bad wirecount");
3758         }
3759 }
3760
3761 /*
3762  * Removes this physical page from all physical maps in which it resides.
3763  * Reflects back modify bits to the pager.
3764  *
3765  * This routine may not be called from an interrupt.
3766  */
3767 static
3768 void
3769 pmap_remove_all(vm_page_t m)
3770 {
3771         struct pmap_inval_info info;
3772         pv_entry_t pv;
3773
3774         if (!pmap_initialized /* || (m->flags & PG_FICTITIOUS)*/)
3775                 return;
3776
3777         pmap_inval_init(&info);
3778         vm_page_spin_lock(m);
3779         while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
3780                 KKASSERT(pv->pv_m == m);
3781                 if (pv_hold_try(pv)) {
3782                         vm_page_spin_unlock(m);
3783                 } else {
3784                         vm_page_spin_unlock(m);
3785                         pv_lock(pv);
3786                 }
3787                 if (pv->pv_m != m) {
3788                         pv_put(pv);
3789                         vm_page_spin_lock(m);
3790                         continue;
3791                 }
3792                 /*
3793                  * Holding no spinlocks, pv is locked.
3794                  */
3795                 pmap_remove_pv_pte(pv, NULL, &info);
3796                 pmap_remove_pv_page(pv);
3797                 pv_free(pv);
3798                 vm_page_spin_lock(m);
3799         }
3800         KKASSERT((m->flags & (PG_MAPPED|PG_WRITEABLE)) == 0);
3801         vm_page_spin_unlock(m);
3802         pmap_inval_done(&info);
3803 }
3804
3805 /*
3806  * Set the physical protection on the specified range of this map
3807  * as requested.  This function is typically only used for debug watchpoints
3808  * and COW pages.
3809  *
3810  * This function may not be called from an interrupt if the map is
3811  * not the kernel_pmap.
3812  *
3813  * NOTE!  For shared page table pages we just unmap the page.
3814  */
3815 void
3816 pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
3817 {
3818         struct pmap_scan_info info;
3819         /* JG review for NX */
3820
3821         if (pmap == NULL)
3822                 return;
3823         if ((prot & VM_PROT_READ) == VM_PROT_NONE) {
3824                 pmap_remove(pmap, sva, eva);
3825                 return;
3826         }
3827         if (prot & VM_PROT_WRITE)
3828                 return;
3829         info.pmap = pmap;
3830         info.sva = sva;
3831         info.eva = eva;
3832         info.func = pmap_protect_callback;
3833         info.arg = &prot;
3834         info.doinval = 1;
3835         pmap_scan(&info);
3836 }
3837
3838 static
3839 void
3840 pmap_protect_callback(pmap_t pmap, struct pmap_scan_info *info,
3841                       pv_entry_t pte_pv, pv_entry_t pt_pv, int sharept,
3842                       vm_offset_t va, pt_entry_t *ptep, void *arg __unused)
3843 {
3844         pt_entry_t pbits;
3845         pt_entry_t cbits;
3846         pt_entry_t pte;
3847         vm_page_t m;
3848
3849         /*
3850          * XXX non-optimal.
3851          */
3852         pmap_inval_interlock(&info->inval, pmap, va);
3853 again:
3854         pbits = *ptep;
3855         cbits = pbits;
3856         if (pte_pv) {
3857                 m = NULL;
3858                 if (pbits & pmap->pmap_bits[PG_A_IDX]) {
3859                         if ((pbits & pmap->pmap_bits[PG_DEVICE_IDX]) == 0) {
3860                                 m = PHYS_TO_VM_PAGE(pbits & PG_FRAME);
3861                                 KKASSERT(m == pte_pv->pv_m);
3862                                 vm_page_flag_set(m, PG_REFERENCED);
3863                         }
3864                         cbits &= ~pmap->pmap_bits[PG_A_IDX];
3865                 }
3866                 if (pbits & pmap->pmap_bits[PG_M_IDX]) {
3867                         if (pmap_track_modified(pte_pv->pv_pindex)) {
3868                                 if ((pbits & pmap->pmap_bits[PG_DEVICE_IDX]) == 0) {
3869                                         if (m == NULL) {
3870                                                 m = PHYS_TO_VM_PAGE(pbits &
3871                                                                     PG_FRAME);
3872                                         }
3873                                         vm_page_dirty(m);
3874                                 }
3875                                 cbits &= ~pmap->pmap_bits[PG_M_IDX];
3876                         }
3877                 }
3878         } else if (sharept) {
3879                 /*
3880                  * Unmanaged page table, pt_pv is actually the pd_pv
3881                  * for our pmap (not the share object pmap).
3882                  *
3883                  * When asked to protect something in a shared page table
3884                  * page we just unmap the page table page.  We have to
3885                  * invalidate the tlb in this situation.
3886                  *
3887                  * XXX Warning, shared page tables will not be used for
3888                  * OBJT_DEVICE or OBJT_MGTDEVICE (PG_FICTITIOUS) mappings
3889                  * so PHYS_TO_VM_PAGE() should be safe here.
3890                  */
3891                 pte = pte_load_clear(ptep);
3892                 pmap_inval_invltlb(&info->inval);
3893                 if (vm_page_unwire_quick(PHYS_TO_VM_PAGE(pte & PG_FRAME)))
3894                         panic("pmap_protect: pgtable1 pg bad wirecount");
3895                 if (vm_page_unwire_quick(pt_pv->pv_m))
3896                         panic("pmap_protect: pgtable2 pg bad wirecount");
3897                 ptep = NULL;
3898         }
3899         /* else unmanaged page, adjust bits, no wire changes */
3900
3901         if (ptep) {
3902                 cbits &= ~pmap->pmap_bits[PG_RW_IDX];
3903                 if (pbits != cbits && !atomic_cmpset_long(ptep, pbits, cbits)) {
3904                         goto again;
3905                 }
3906         }
3907         pmap_inval_deinterlock(&info->inval, pmap);
3908         if (pte_pv)
3909                 pv_put(pte_pv);
3910 }
3911
3912 /*
3913  * Insert the vm_page (m) at the virtual address (va), replacing any prior
3914  * mapping at that address.  Set protection and wiring as requested.
3915  *
3916  * If entry is non-NULL we check to see if the SEG_SIZE optimization is
3917  * possible.  If it is we enter the page into the appropriate shared pmap
3918  * hanging off the related VM object instead of the passed pmap, then we
3919  * share the page table page from the VM object's pmap into the current pmap.
3920  *
3921  * NOTE: This routine MUST insert the page into the pmap now, it cannot
3922  *       lazy-evaluate.
3923  */
3924 void
3925 pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
3926            boolean_t wired, vm_map_entry_t entry)
3927 {
3928         pmap_inval_info info;
3929         pv_entry_t pt_pv;       /* page table */
3930         pv_entry_t pte_pv;      /* page table entry */
3931         pt_entry_t *ptep;
3932         vm_paddr_t opa;
3933         pt_entry_t origpte, newpte;
3934         vm_paddr_t pa;
3935
3936         if (pmap == NULL)
3937                 return;
3938         va = trunc_page(va);
3939 #ifdef PMAP_DIAGNOSTIC
3940         if (va >= KvaEnd)
3941                 panic("pmap_enter: toobig");
3942         if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS))
3943                 panic("pmap_enter: invalid to pmap_enter page table "
3944                       "pages (va: 0x%lx)", va);
3945 #endif
3946         if (va < UPT_MAX_ADDRESS && pmap == &kernel_pmap) {
3947                 kprintf("Warning: pmap_enter called on UVA with "
3948                         "kernel_pmap\n");
3949 #ifdef DDB
3950                 db_print_backtrace();
3951 #endif
3952         }
3953         if (va >= UPT_MAX_ADDRESS && pmap != &kernel_pmap) {
3954                 kprintf("Warning: pmap_enter called on KVA without"
3955                         "kernel_pmap\n");
3956 #ifdef DDB
3957                 db_print_backtrace();
3958 #endif
3959         }
3960
3961         /*
3962          * Get locked PV entries for our new page table entry (pte_pv)
3963          * and for its parent page table (pt_pv).  We need the parent
3964          * so we can resolve the location of the ptep.
3965          *
3966          * Only hardware MMU actions can modify the ptep out from
3967          * under us.
3968          *
3969          * if (m) is fictitious or unmanaged we do not create a managing
3970          * pte_pv for it.  Any pre-existing page's management state must
3971          * match (avoiding code complexity).
3972          *
3973          * If the pmap is still being initialized we assume existing
3974          * page tables.
3975          *
3976          * Kernel mapppings do not track page table pages (i.e. pt_pv).
3977          */
3978         if (pmap_initialized == FALSE) {
3979                 pte_pv = NULL;
3980                 pt_pv = NULL;
3981                 ptep = vtopte(va);
3982                 origpte = *ptep;
3983         } else if (m->flags & (/*PG_FICTITIOUS |*/ PG_UNMANAGED)) { /* XXX */
3984                 pte_pv = NULL;
3985                 if (va >= VM_MAX_USER_ADDRESS) {
3986                         pt_pv = NULL;
3987                         ptep = vtopte(va);
3988                 } else {
3989                         pt_pv = pmap_allocpte_seg(pmap, pmap_pt_pindex(va),
3990                                                   NULL, entry, va);
3991                         ptep = pv_pte_lookup(pt_pv, pmap_pte_index(va));
3992                 }
3993                 origpte = *ptep;
3994                 cpu_ccfence();
3995                 KKASSERT(origpte == 0 ||
3996                          (origpte & pmap->pmap_bits[PG_MANAGED_IDX]) == 0);
3997         } else {
3998                 if (va >= VM_MAX_USER_ADDRESS) {
3999                         /*
4000                          * Kernel map, pv_entry-tracked.
4001                          */
4002                         pt_pv = NULL;
4003                         pte_pv = pmap_allocpte(pmap, pmap_pte_pindex(va), NULL);
4004                         ptep = vtopte(va);
4005                 } else {
4006                         /*
4007                          * User map
4008                          */
4009                         pte_pv = pmap_allocpte_seg(pmap, pmap_pte_pindex(va),
4010                                                    &pt_pv, entry, va);
4011                         ptep = pv_pte_lookup(pt_pv, pmap_pte_index(va));
4012                 }
4013                 origpte = *ptep;
4014                 cpu_ccfence();
4015                 KKASSERT(origpte == 0 ||
4016                          (origpte & pmap->pmap_bits[PG_MANAGED_IDX]));
4017         }
4018
4019         pa = VM_PAGE_TO_PHYS(m);
4020         opa = origpte & PG_FRAME;
4021
4022         newpte = (pt_entry_t)(pa | pte_prot(pmap, prot) |
4023                  pmap->pmap_bits[PG_V_IDX] | pmap->pmap_bits[PG_A_IDX]);
4024         if (wired)
4025                 newpte |= pmap->pmap_bits[PG_W_IDX];
4026         if (va < VM_MAX_USER_ADDRESS)
4027                 newpte |= pmap->pmap_bits[PG_U_IDX];
4028         if (pte_pv)
4029                 newpte |= pmap->pmap_bits[PG_MANAGED_IDX];
4030 //      if (pmap == &kernel_pmap)
4031 //              newpte |= pgeflag;
4032         newpte |= pmap->pmap_cache_bits[m->pat_mode];
4033         if (m->flags & PG_FICTITIOUS)
4034                 newpte |= pmap->pmap_bits[PG_DEVICE_IDX];
4035
4036         /*
4037          * It is possible for multiple faults to occur in threaded
4038          * environments, the existing pte might be correct.
4039          */
4040         if (((origpte ^ newpte) & ~(pt_entry_t)(pmap->pmap_bits[PG_M_IDX] |
4041             pmap->pmap_bits[PG_A_IDX])) == 0)
4042                 goto done;
4043
4044         if ((prot & VM_PROT_NOSYNC) == 0)
4045                 pmap_inval_init(&info);
4046
4047         /*
4048          * Ok, either the address changed or the protection or wiring
4049          * changed.
4050          *
4051          * Clear the current entry, interlocking the removal.  For managed
4052          * pte's this will also flush the modified state to the vm_page.
4053          * Atomic ops are mandatory in order to ensure that PG_M events are
4054          * not lost during any transition.
4055          *
4056          * WARNING: The caller has busied the new page but not the original
4057          *          vm_page which we are trying to replace.  Because we hold
4058          *          the pte_pv lock, but have not busied the page, PG bits
4059          *          can be cleared out from under us.
4060          */
4061         if (opa) {
4062                 if (pte_pv) {
4063                         /*
4064                          * pmap_remove_pv_pte() unwires pt_pv and assumes
4065                          * we will free pte_pv, but since we are reusing
4066                          * pte_pv we want to retain the wire count.
4067                          *
4068                          * pt_pv won't exist for a kernel page (managed or
4069                          * otherwise).
4070                          */
4071                         if (pt_pv)
4072                                 vm_page_wire_quick(pt_pv->pv_m);
4073                         if (prot & VM_PROT_NOSYNC)
4074                                 pmap_remove_pv_pte(pte_pv, pt_pv, NULL);
4075                         else
4076                                 pmap_remove_pv_pte(pte_pv, pt_pv, &info);
4077                         if (pte_pv->pv_m)
4078                                 pmap_remove_pv_page(pte_pv);
4079                 } else if (prot & VM_PROT_NOSYNC) {
4080                         /*
4081                          * Unmanaged page, NOSYNC (no mmu sync) requested.
4082                          *
4083                          * Leave wire count on PT page intact.
4084                          */
4085                         (void)pte_load_clear(ptep);
4086                         cpu_invlpg((void *)va);
4087                         atomic_add_long(&pmap->pm_stats.resident_count, -1);
4088                 } else {
4089                         /*
4090                          * Unmanaged page, normal enter.
4091                          *
4092                          * Leave wire count on PT page intact.
4093                          */
4094                         pmap_inval_interlock(&info, pmap, va);
4095                         (void)pte_load_clear(ptep);
4096                         pmap_inval_deinterlock(&info, pmap);
4097                         atomic_add_long(&pmap->pm_stats.resident_count, -1);
4098                 }
4099                 KKASSERT(*ptep == 0);
4100         }
4101
4102         if (pte_pv) {
4103                 /*
4104                  * Enter on the PV list if part of our managed memory.
4105                  * Wiring of the PT page is already handled.
4106                  */
4107                 KKASSERT(pte_pv->pv_m == NULL);
4108                 vm_page_spin_lock(m);
4109                 pte_pv->pv_m = m;
4110                 pmap_page_stats_adding(m);
4111                 TAILQ_INSERT_TAIL(&m->md.pv_list, pte_pv, pv_list);
4112                 vm_page_flag_set(m, PG_MAPPED);
4113                 vm_page_spin_unlock(m);
4114         } else if (pt_pv && opa == 0) {
4115                 /*
4116                  * We have to adjust the wire count on the PT page ourselves
4117                  * for unmanaged entries.  If opa was non-zero we retained
4118                  * the existing wire count from the removal.
4119                  */
4120                 vm_page_wire_quick(pt_pv->pv_m);
4121         }
4122
4123         /*
4124          * Kernel VMAs (pt_pv == NULL) require pmap invalidation interlocks.
4125          *
4126          * User VMAs do not because those will be zero->non-zero, so no
4127          * stale entries to worry about at this point.
4128          *
4129          * For KVM there appear to still be issues.  Theoretically we
4130          * should be able to scrap the interlocks entirely but we
4131          * get crashes.
4132          */
4133         if ((prot & VM_PROT_NOSYNC) == 0 && pt_pv == NULL)
4134                 pmap_inval_interlock(&info, pmap, va);
4135
4136         /*
4137          * Set the pte
4138          */
4139         *(volatile pt_entry_t *)ptep = newpte;
4140
4141         if ((prot & VM_PROT_NOSYNC) == 0 && pt_pv == NULL)
4142                 pmap_inval_deinterlock(&info, pmap);
4143         else if (pt_pv == NULL)
4144                 cpu_invlpg((void *)va);
4145
4146         if (wired) {
4147                 if (pte_pv) {
4148                         atomic_add_long(&pte_pv->pv_pmap->pm_stats.wired_count,
4149                                         1);
4150                 } else {
4151                         atomic_add_long(&pmap->pm_stats.wired_count, 1);
4152                 }
4153         }
4154         if (newpte & pmap->pmap_bits[PG_RW_IDX])
4155                 vm_page_flag_set(m, PG_WRITEABLE);
4156
4157         /*
4158          * Unmanaged pages need manual resident_count tracking.
4159          */
4160         if (pte_pv == NULL && pt_pv)
4161                 atomic_add_long(&pt_pv->pv_pmap->pm_stats.resident_count, 1);
4162
4163         /*
4164          * Cleanup
4165          */
4166         if ((prot & VM_PROT_NOSYNC) == 0 || pte_pv == NULL)
4167                 pmap_inval_done(&info);
4168 done:
4169         KKASSERT((newpte & pmap->pmap_bits[PG_MANAGED_IDX]) == 0 ||
4170                  (m->flags & PG_MAPPED));
4171
4172         /*
4173          * Cleanup the pv entry, allowing other accessors.
4174          */
4175         if (pte_pv)
4176                 pv_put(pte_pv);
4177         if (pt_pv)
4178                 pv_put(pt_pv);
4179 }
4180
4181 /*
4182  * This code works like pmap_enter() but assumes VM_PROT_READ and not-wired.
4183  * This code also assumes that the pmap has no pre-existing entry for this
4184  * VA.
4185  *
4186  * This code currently may only be used on user pmaps, not kernel_pmap.
4187  */
4188 void
4189 pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m)
4190 {
4191         pmap_enter(pmap, va, m, VM_PROT_READ, FALSE, NULL);
4192 }
4193
4194 /*
4195  * Make a temporary mapping for a physical address.  This is only intended
4196  * to be used for panic dumps.
4197  *
4198  * The caller is responsible for calling smp_invltlb().
4199  */
4200 void *
4201 pmap_kenter_temporary(vm_paddr_t pa, long i)
4202 {
4203         pmap_kenter_quick((vm_offset_t)crashdumpmap + (i * PAGE_SIZE), pa);
4204         return ((void *)crashdumpmap);
4205 }
4206
4207 #define MAX_INIT_PT (96)
4208
4209 /*
4210  * This routine preloads the ptes for a given object into the specified pmap.
4211  * This eliminates the blast of soft faults on process startup and
4212  * immediately after an mmap.
4213  */
4214 static int pmap_object_init_pt_callback(vm_page_t p, void *data);
4215
4216 void
4217 pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, vm_prot_t prot,
4218                     vm_object_t object, vm_pindex_t pindex,
4219                     vm_size_t size, int limit)
4220 {
4221         struct rb_vm_page_scan_info info;
4222         struct lwp *lp;
4223         vm_size_t psize;
4224
4225         /*
4226          * We can't preinit if read access isn't set or there is no pmap
4227          * or object.
4228          */
4229         if ((prot & VM_PROT_READ) == 0 || pmap == NULL || object == NULL)
4230                 return;
4231
4232         /*
4233          * We can't preinit if the pmap is not the current pmap
4234          */
4235         lp = curthread->td_lwp;
4236         if (lp == NULL || pmap != vmspace_pmap(lp->lwp_vmspace))
4237                 return;
4238
4239         /*
4240          * Misc additional checks
4241          */
4242         psize = x86_64_btop(size);
4243
4244         if ((object->type != OBJT_VNODE) ||
4245                 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) &&
4246                         (object->resident_page_count > MAX_INIT_PT))) {
4247                 return;
4248         }
4249
4250         if (pindex + psize > object->size) {
4251                 if (object->size < pindex)
4252                         return;           
4253                 psize = object->size - pindex;
4254         }
4255
4256         if (psize == 0)
4257                 return;
4258
4259         /*
4260          * If everything is segment-aligned do not pre-init here.  Instead
4261          * allow the normal vm_fault path to pass a segment hint to
4262          * pmap_enter() which will then use an object-referenced shared
4263          * page table page.
4264          */
4265         if ((addr & SEG_MASK) == 0 &&
4266             (ctob(psize) & SEG_MASK) == 0 &&
4267             (ctob(pindex) & SEG_MASK) == 0) {
4268                 return;
4269         }
4270
4271         /*
4272          * Use a red-black scan to traverse the requested range and load
4273          * any valid pages found into the pmap.
4274          *
4275          * We cannot safely scan the object's memq without holding the
4276          * object token.
4277          */
4278         info.start_pindex = pindex;
4279         info.end_pindex = pindex + psize - 1;
4280         info.limit = limit;
4281         info.mpte = NULL;
4282         info.addr = addr;
4283         info.pmap = pmap;
4284
4285         vm_object_hold_shared(object);
4286         vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp,
4287                                 pmap_object_init_pt_callback, &info);
4288         vm_object_drop(object);
4289 }
4290
4291 static
4292 int
4293 pmap_object_init_pt_callback(vm_page_t p, void *data)
4294 {
4295         struct rb_vm_page_scan_info *info = data;
4296         vm_pindex_t rel_index;
4297
4298         /*
4299          * don't allow an madvise to blow away our really
4300          * free pages allocating pv entries.
4301          */
4302         if ((info->limit & MAP_PREFAULT_MADVISE) &&
4303                 vmstats.v_free_count < vmstats.v_free_reserved) {
4304                     return(-1);
4305         }
4306
4307         /*
4308          * Ignore list markers and ignore pages we cannot instantly
4309          * busy (while holding the object token).
4310          */
4311         if (p->flags & PG_MARKER)
4312                 return 0;
4313         if (vm_page_busy_try(p, TRUE))
4314                 return 0;
4315         if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) &&
4316             (p->flags & PG_FICTITIOUS) == 0) {
4317                 if ((p->queue - p->pc) == PQ_CACHE)
4318                         vm_page_deactivate(p);
4319                 rel_index = p->pindex - info->start_pindex;
4320                 pmap_enter_quick(info->pmap,
4321                                  info->addr + x86_64_ptob(rel_index), p);
4322         }
4323         vm_page_wakeup(p);
4324         lwkt_yield();
4325         return(0);
4326 }
4327
4328 /*
4329  * Return TRUE if the pmap is in shape to trivially pre-fault the specified
4330  * address.
4331  *
4332  * Returns FALSE if it would be non-trivial or if a pte is already loaded
4333  * into the slot.
4334  *
4335  * XXX This is safe only because page table pages are not freed.
4336  */
4337 int
4338 pmap_prefault_ok(pmap_t pmap, vm_offset_t addr)
4339 {
4340         pt_entry_t *pte;
4341
4342         /*spin_lock(&pmap->pm_spin);*/
4343         if ((pte = pmap_pte(pmap, addr)) != NULL) {
4344                 if (*pte & pmap->pmap_bits[PG_V_IDX]) {
4345                         /*spin_unlock(&pmap->pm_spin);*/
4346                         return FALSE;
4347                 }
4348         }
4349         /*spin_unlock(&pmap->pm_spin);*/
4350         return TRUE;
4351 }
4352
4353 /*
4354  * Change the wiring attribute for a pmap/va pair.  The mapping must already
4355  * exist in the pmap.  The mapping may or may not be managed.
4356  */
4357 void
4358 pmap_change_wiring(pmap_t pmap, vm_offset_t va, boolean_t wired,
4359                    vm_map_entry_t entry)
4360 {
4361         pt_entry_t *ptep;
4362         pv_entry_t pv;
4363
4364         if (pmap == NULL)
4365                 return;
4366         lwkt_gettoken(&pmap->pm_token);
4367         pv = pmap_allocpte_seg(pmap, pmap_pt_pindex(va), NULL, entry, va);
4368         ptep = pv_pte_lookup(pv, pmap_pte_index(va));
4369
4370         if (wired && !pmap_pte_w(pmap, ptep))
4371                 atomic_add_long(&pv->pv_pmap->pm_stats.wired_count, 1);
4372         else if (!wired && pmap_pte_w(pmap, ptep))
4373                 atomic_add_long(&pv->pv_pmap->pm_stats.wired_count, -1);
4374
4375         /*
4376          * Wiring is not a hardware characteristic so there is no need to
4377          * invalidate TLB.  However, in an SMP environment we must use
4378          * a locked bus cycle to update the pte (if we are not using 
4379          * the pmap_inval_*() API that is)... it's ok to do this for simple
4380          * wiring changes.
4381          */
4382         if (wired)
4383                 atomic_set_long(ptep, pmap->pmap_bits[PG_W_IDX]);
4384         else
4385                 atomic_clear_long(ptep, pmap->pmap_bits[PG_W_IDX]);
4386         pv_put(pv);
4387         lwkt_reltoken(&pmap->pm_token);
4388 }
4389
4390
4391
4392 /*
4393  * Copy the range specified by src_addr/len from the source map to
4394  * the range dst_addr/len in the destination map.
4395  *
4396  * This routine is only advisory and need not do anything.
4397  */
4398 void
4399 pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, 
4400           vm_size_t len, vm_offset_t src_addr)
4401 {
4402 }       
4403
4404 /*
4405  * pmap_zero_page:
4406  *
4407  *      Zero the specified physical page.
4408  *
4409  *      This function may be called from an interrupt and no locking is
4410  *      required.
4411  */
4412 void
4413 pmap_zero_page(vm_paddr_t phys)
4414 {
4415         vm_offset_t va = PHYS_TO_DMAP(phys);
4416
4417         pagezero((void *)va);
4418 }
4419
4420 /*
4421  * pmap_page_assertzero:
4422  *
4423  *      Assert that a page is empty, panic if it isn't.
4424  */
4425 void
4426 pmap_page_assertzero(vm_paddr_t phys)
4427 {
4428         vm_offset_t va = PHYS_TO_DMAP(phys);
4429         size_t i;
4430
4431         for (i = 0; i < PAGE_SIZE; i += sizeof(long)) {
4432                 if (*(long *)((char *)va + i) != 0) {
4433                         panic("pmap_page_assertzero() @ %p not zero!",
4434                               (void *)(intptr_t)va);
4435                 }
4436         }
4437 }
4438
4439 /*
4440  * pmap_zero_page:
4441  *
4442  *      Zero part of a physical page by mapping it into memory and clearing
4443  *      its contents with bzero.
4444  *
4445  *      off and size may not cover an area beyond a single hardware page.
4446  */
4447 void
4448 pmap_zero_page_area(vm_paddr_t phys, int off, int size)
4449 {
4450         vm_offset_t virt = PHYS_TO_DMAP(phys);
4451
4452         bzero((char *)virt + off, size);
4453 }
4454
4455 /*
4456  * pmap_copy_page:
4457  *
4458  *      Copy the physical page from the source PA to the target PA.
4459  *      This function may be called from an interrupt.  No locking
4460  *      is required.
4461  */
4462 void
4463 pmap_copy_page(vm_paddr_t src, vm_paddr_t dst)
4464 {
4465         vm_offset_t src_virt, dst_virt;
4466
4467         src_virt = PHYS_TO_DMAP(src);
4468         dst_virt = PHYS_TO_DMAP(dst);
4469         bcopy((void *)src_virt, (void *)dst_virt, PAGE_SIZE);
4470 }
4471
4472 /*
4473  * pmap_copy_page_frag:
4474  *
4475  *      Copy the physical page from the source PA to the target PA.
4476  *      This function may be called from an interrupt.  No locking
4477  *      is required.
4478  */
4479 void
4480 pmap_copy_page_frag(vm_paddr_t src, vm_paddr_t dst, size_t bytes)
4481 {
4482         vm_offset_t src_virt, dst_virt;
4483
4484         src_virt = PHYS_TO_DMAP(src);
4485         dst_virt = PHYS_TO_DMAP(dst);
4486
4487         bcopy((char *)src_virt + (src & PAGE_MASK),
4488               (char *)dst_virt + (dst & PAGE_MASK),
4489               bytes);
4490 }
4491
4492 /*
4493  * Returns true if the pmap's pv is one of the first 16 pvs linked to from
4494  * this page.  This count may be changed upwards or downwards in the future;
4495  * it is only necessary that true be returned for a small subset of pmaps
4496  * for proper page aging.
4497  */
4498 boolean_t
4499 pmap_page_exists_quick(pmap_t pmap, vm_page_t m)
4500 {
4501         pv_entry_t pv;
4502         int loops = 0;
4503
4504         if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
4505                 return FALSE;
4506
4507         vm_page_spin_lock(m);
4508         TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
4509                 if (pv->pv_pmap == pmap) {
4510                         vm_page_spin_unlock(m);
4511                         return TRUE;
4512                 }
4513                 loops++;
4514                 if (loops >= 16)
4515                         break;
4516         }
4517         vm_page_spin_unlock(m);
4518         return (FALSE);
4519 }
4520
4521 /*
4522  * Remove all pages from specified address space this aids process exit
4523  * speeds.  Also, this code may be special cased for the current process
4524  * only.
4525  */
4526 void
4527 pmap_remove_pages(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
4528 {
4529         pmap_remove_noinval(pmap, sva, eva);
4530         cpu_invltlb();
4531 }
4532
4533 /*
4534  * pmap_testbit tests bits in pte's note that the testbit/clearbit
4535  * routines are inline, and a lot of things compile-time evaluate.
4536  */
4537 static
4538 boolean_t
4539 pmap_testbit(vm_page_t m, int bit)
4540 {
4541         pv_entry_t pv;
4542         pt_entry_t *pte;
4543         pmap_t pmap;
4544
4545         if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
4546                 return FALSE;
4547
4548         if (TAILQ_FIRST(&m->md.pv_list) == NULL)
4549                 return FALSE;
4550         vm_page_spin_lock(m);
4551         if (TAILQ_FIRST(&m->md.pv_list) == NULL) {
4552                 vm_page_spin_unlock(m);
4553                 return FALSE;
4554         }
4555
4556         TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
4557
4558 #if defined(PMAP_DIAGNOSTIC)
4559                 if (pv->pv_pmap == NULL) {
4560                         kprintf("Null pmap (tb) at pindex: %"PRIu64"\n",
4561                             pv->pv_pindex);
4562                         continue;
4563                 }
4564 #endif
4565                 pmap = pv->pv_pmap;
4566
4567                 /*
4568                  * If the bit being tested is the modified bit, then
4569                  * mark clean_map and ptes as never
4570                  * modified.
4571                  *
4572                  * WARNING!  Because we do not lock the pv, *pte can be in a
4573                  *           state of flux.  Despite this the value of *pte
4574                  *           will still be related to the vm_page in some way
4575                  *           because the pv cannot be destroyed as long as we
4576                  *           hold the vm_page spin lock.
4577                  */
4578                 if (bit == PG_A_IDX || bit == PG_M_IDX) {
4579                                 //& (pmap->pmap_bits[PG_A_IDX] | pmap->pmap_bits[PG_M_IDX])) {
4580                         if (!pmap_track_modified(pv->pv_pindex))
4581                                 continue;
4582                 }
4583
4584                 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_pindex << PAGE_SHIFT);
4585                 if (*pte & pmap->pmap_bits[bit]) {
4586                         vm_page_spin_unlock(m);
4587                         return TRUE;
4588                 }
4589         }
4590         vm_page_spin_unlock(m);
4591         return (FALSE);
4592 }
4593
4594 /*
4595  * This routine is used to modify bits in ptes.  Only one bit should be
4596  * specified.  PG_RW requires special handling.
4597  *
4598  * Caller must NOT hold any spin locks
4599  */
4600 static __inline
4601 void
4602 pmap_clearbit(vm_page_t m, int bit_index)
4603 {
4604         struct pmap_inval_info info;
4605         pv_entry_t pv;
4606         pt_entry_t *pte;
4607         pt_entry_t pbits;
4608         pmap_t pmap;
4609
4610         if (bit_index == PG_RW_IDX)
4611                 vm_page_flag_clear(m, PG_WRITEABLE);
4612         if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) {
4613                 return;
4614         }
4615
4616         /*
4617          * PG_M or PG_A case
4618          *
4619          * Loop over all current mappings setting/clearing as appropos If
4620          * setting RO do we need to clear the VAC?
4621          *
4622          * NOTE: When clearing PG_M we could also (not implemented) drop
4623          *       through to the PG_RW code and clear PG_RW too, forcing
4624          *       a fault on write to redetect PG_M for virtual kernels, but
4625          *       it isn't necessary since virtual kernels invalidate the
4626          *       pte when they clear the VPTE_M bit in their virtual page
4627          *       tables.
4628          *
4629          * NOTE: Does not re-dirty the page when clearing only PG_M.
4630          *
4631          * NOTE: Because we do not lock the pv, *pte can be in a state of
4632          *       flux.  Despite this the value of *pte is still somewhat
4633          *       related while we hold the vm_page spin lock.
4634          *
4635          *       *pte can be zero due to this race.  Since we are clearing
4636          *       bits we basically do no harm when this race  ccurs.
4637          */
4638         if (bit_index != PG_RW_IDX) {
4639                 vm_page_spin_lock(m);
4640                 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
4641 #if defined(PMAP_DIAGNOSTIC)
4642                         if (pv->pv_pmap == NULL) {
4643                                 kprintf("Null pmap (cb) at pindex: %"PRIu64"\n",
4644                                     pv->pv_pindex);
4645                                 continue;
4646                         }
4647 #endif
4648                         pmap = pv->pv_pmap;
4649                         pte = pmap_pte_quick(pv->pv_pmap,
4650                                              pv->pv_pindex << PAGE_SHIFT);
4651                         pbits = *pte;
4652                         if (pbits & pmap->pmap_bits[bit_index])
4653                                 atomic_clear_long(pte, pmap->pmap_bits[bit_index]);
4654                 }
4655                 vm_page_spin_unlock(m);
4656                 return;
4657         }
4658
4659         /*
4660          * Clear PG_RW.  Also clears PG_M and marks the page dirty if PG_M
4661          * was set.
4662          */
4663         pmap_inval_init(&info);
4664
4665 restart:
4666         vm_page_spin_lock(m);
4667         TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
4668                 /*
4669                  * don't write protect pager mappings
4670                  */
4671                 if (!pmap_track_modified(pv->pv_pindex))
4672                         continue;
4673
4674 #if defined(PMAP_DIAGNOSTIC)
4675                 if (pv->pv_pmap == NULL) {
4676                         kprintf("Null pmap (cb) at pindex: %"PRIu64"\n",
4677                             pv->pv_pindex);
4678                         continue;
4679                 }
4680 #endif
4681                 pmap = pv->pv_pmap;
4682                 /*
4683                  * Skip pages which do not have PG_RW set.
4684                  */
4685                 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_pindex << PAGE_SHIFT);
4686                 if ((*pte & pmap->pmap_bits[PG_RW_IDX]) == 0)
4687                         continue;
4688
4689                 /*
4690                  * Lock the PV
4691                  */
4692                 if (pv_hold_try(pv)) {
4693                         vm_page_spin_unlock(m);
4694                 } else {
4695                         vm_page_spin_unlock(m);
4696                         pv_lock(pv);    /* held, now do a blocking lock */
4697                 }
4698                 if (pv->pv_pmap != pmap || pv->pv_m != m) {
4699                         pv_put(pv);     /* and release */
4700                         goto restart;   /* anything could have happened */
4701                 }
4702                 pmap_inval_interlock(&info, pmap,
4703                                      (vm_offset_t)pv->pv_pindex << PAGE_SHIFT);
4704                 KKASSERT(pv->pv_pmap == pmap);
4705                 for (;;) {
4706                         pbits = *pte;
4707                         cpu_ccfence();
4708                         if (atomic_cmpset_long(pte, pbits, pbits &
4709                             ~(pmap->pmap_bits[PG_RW_IDX] |
4710                             pmap->pmap_bits[PG_M_IDX]))) {
4711                                 break;
4712                         }
4713                 }
4714                 pmap_inval_deinterlock(&info, pmap);
4715                 vm_page_spin_lock(m);
4716
4717                 /*
4718                  * If PG_M was found to be set while we were clearing PG_RW
4719                  * we also clear PG_M (done above) and mark the page dirty.
4720                  * Callers expect this behavior.
4721                  */
4722                 if (pbits & pmap->pmap_bits[PG_M_IDX])
4723                         vm_page_dirty(m);
4724                 pv_put(pv);
4725         }
4726         vm_page_spin_unlock(m);
4727         pmap_inval_done(&info);
4728 }
4729
4730 /*
4731  * Lower the permission for all mappings to a given page.
4732  *
4733  * Page must be busied by caller.  Because page is busied by caller this
4734  * should not be able to race a pmap_enter().
4735  */
4736 void
4737 pmap_page_protect(vm_page_t m, vm_prot_t prot)
4738 {
4739         /* JG NX support? */
4740         if ((prot & VM_PROT_WRITE) == 0) {
4741                 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) {
4742                         /*
4743                          * NOTE: pmap_clearbit(.. PG_RW) also clears
4744                          *       the PG_WRITEABLE flag in (m).
4745                          */
4746                         pmap_clearbit(m, PG_RW_IDX);
4747                 } else {
4748                         pmap_remove_all(m);
4749                 }
4750         }
4751 }
4752
4753 vm_paddr_t
4754 pmap_phys_address(vm_pindex_t ppn)
4755 {
4756         return (x86_64_ptob(ppn));
4757 }
4758
4759 /*
4760  * Return a count of reference bits for a page, clearing those bits.
4761  * It is not necessary for every reference bit to be cleared, but it
4762  * is necessary that 0 only be returned when there are truly no
4763  * reference bits set.
4764  *
4765  * XXX: The exact number of bits to check and clear is a matter that
4766  * should be tested and standardized at some point in the future for
4767  * optimal aging of shared pages.
4768  *
4769  * This routine may not block.
4770  */
4771 int
4772 pmap_ts_referenced(vm_page_t m)
4773 {
4774         pv_entry_t pv;
4775         pt_entry_t *pte;
4776         pmap_t pmap;
4777         int rtval = 0;
4778
4779         if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
4780                 return (rtval);
4781
4782         vm_page_spin_lock(m);
4783         TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
4784                 if (!pmap_track_modified(pv->pv_pindex))
4785                         continue;
4786                 pmap = pv->pv_pmap;
4787                 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_pindex << PAGE_SHIFT);
4788                 if (pte && (*pte & pmap->pmap_bits[PG_A_IDX])) {
4789                         atomic_clear_long(pte, pmap->pmap_bits[PG_A_IDX]);
4790                         rtval++;
4791                         if (rtval > 4)
4792                                 break;
4793                 }
4794         }
4795         vm_page_spin_unlock(m);
4796         return (rtval);
4797 }
4798
4799 /*
4800  *      pmap_is_modified:
4801  *
4802  *      Return whether or not the specified physical page was modified
4803  *      in any physical maps.
4804  */
4805 boolean_t
4806 pmap_is_modified(vm_page_t m)
4807 {
4808         boolean_t res;
4809
4810         res = pmap_testbit(m, PG_M_IDX);
4811         return (res);
4812 }
4813
4814 /*
4815  *      Clear the modify bits on the specified physical page.
4816  */
4817 void
4818 pmap_clear_modify(vm_page_t m)
4819 {
4820         pmap_clearbit(m, PG_M_IDX);
4821 }
4822
4823 /*
4824  *      pmap_clear_reference:
4825  *
4826  *      Clear the reference bit on the specified physical page.
4827  */
4828 void
4829 pmap_clear_reference(vm_page_t m)
4830 {
4831         pmap_clearbit(m, PG_A_IDX);
4832 }
4833
4834 /*
4835  * Miscellaneous support routines follow
4836  */
4837
4838 static
4839 void
4840 i386_protection_init(void)
4841 {
4842         int *kp, prot;
4843
4844         /* JG NX support may go here; No VM_PROT_EXECUTE ==> set NX bit  */
4845         kp = protection_codes;
4846         for (prot = 0; prot < PROTECTION_CODES_SIZE; prot++) {
4847                 switch (prot) {
4848                 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE:
4849                         /*
4850                          * Read access is also 0. There isn't any execute bit,
4851                          * so just make it readable.
4852                          */
4853                 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE:
4854                 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE:
4855                 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE:
4856                         *kp++ = 0;
4857                         break;
4858                 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE:
4859                 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE:
4860                 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE:
4861                 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE:
4862                         *kp++ = pmap_bits_default[PG_RW_IDX];
4863                         break;
4864                 }
4865         }
4866 }
4867
4868 /*
4869  * Map a set of physical memory pages into the kernel virtual
4870  * address space. Return a pointer to where it is mapped. This
4871  * routine is intended to be used for mapping device memory,
4872  * NOT real memory.
4873  *
4874  * NOTE: We can't use pgeflag unless we invalidate the pages one at
4875  *       a time.
4876  *
4877  * NOTE: The PAT attributes {WRITE_BACK, WRITE_THROUGH, UNCACHED, UNCACHEABLE}
4878  *       work whether the cpu supports PAT or not.  The remaining PAT
4879  *       attributes {WRITE_PROTECTED, WRITE_COMBINING} only work if the cpu
4880  *       supports PAT.
4881  */
4882 void *
4883 pmap_mapdev(vm_paddr_t pa, vm_size_t size)
4884 {
4885         return(pmap_mapdev_attr(pa, size, PAT_WRITE_BACK));
4886 }
4887
4888 void *
4889 pmap_mapdev_uncacheable(vm_paddr_t pa, vm_size_t size)
4890 {
4891         return(pmap_mapdev_attr(pa, size, PAT_UNCACHEABLE));
4892 }
4893
4894 void *
4895 pmap_mapbios(vm_paddr_t pa, vm_size_t size)
4896 {
4897         return (pmap_mapdev_attr(pa, size, PAT_WRITE_BACK));
4898 }
4899
4900 /*
4901  * Map a set of physical memory pages into the kernel virtual
4902  * address space. Return a pointer to where it is mapped. This
4903  * routine is intended to be used for mapping device memory,
4904  * NOT real memory.
4905  */
4906 void *
4907 pmap_mapdev_attr(vm_paddr_t pa, vm_size_t size, int mode)
4908 {
4909         vm_offset_t va, tmpva, offset;
4910         pt_entry_t *pte;
4911         vm_size_t tmpsize;
4912
4913         offset = pa & PAGE_MASK;
4914         size = roundup(offset + size, PAGE_SIZE);
4915
4916         va = kmem_alloc_nofault(&kernel_map, size, PAGE_SIZE);
4917         if (va == 0)
4918                 panic("pmap_mapdev: Couldn't alloc kernel virtual memory");
4919
4920         pa = pa & ~PAGE_MASK;
4921         for (tmpva = va, tmpsize = size; tmpsize > 0;) {
4922                 pte = vtopte(tmpva);
4923                 *pte = pa |
4924                     kernel_pmap.pmap_bits[PG_RW_IDX] |
4925                     kernel_pmap.pmap_bits[PG_V_IDX] | /* pgeflag | */
4926                     kernel_pmap.pmap_cache_bits[mode];
4927                 tmpsize -= PAGE_SIZE;
4928                 tmpva += PAGE_SIZE;
4929                 pa += PAGE_SIZE;
4930         }
4931         pmap_invalidate_range(&kernel_pmap, va, va + size);
4932         pmap_invalidate_cache_range(va, va + size);
4933
4934         return ((void *)(va + offset));
4935 }
4936
4937 void
4938 pmap_unmapdev(vm_offset_t va, vm_size_t size)
4939 {
4940         vm_offset_t base, offset;
4941
4942         base = va & ~PAGE_MASK;
4943         offset = va & PAGE_MASK;
4944         size = roundup(offset + size, PAGE_SIZE);
4945         pmap_qremove(va, size >> PAGE_SHIFT);
4946         kmem_free(&kernel_map, base, size);
4947 }
4948
4949 /*
4950  * Sets the memory attribute for the specified page.
4951  */
4952 void
4953 pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma)
4954 {
4955
4956     m->pat_mode = ma;
4957
4958     /*
4959      * If "m" is a normal page, update its direct mapping.  This update
4960      * can be relied upon to perform any cache operations that are
4961      * required for data coherence.
4962      */
4963     if ((m->flags & PG_FICTITIOUS) == 0)
4964         pmap_change_attr(PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m)), PAGE_SIZE,
4965         m->pat_mode);
4966 }
4967
4968 /*
4969  * Change the PAT attribute on an existing kernel memory map.  Caller
4970  * must ensure that the virtual memory in question is not accessed
4971  * during the adjustment.
4972  */
4973 void
4974 pmap_change_attr(vm_offset_t va, vm_size_t count, int mode)
4975 {
4976         pt_entry_t *pte;
4977         vm_offset_t base;
4978         int changed = 0;
4979
4980         if (va == 0)
4981                 panic("pmap_change_attr: va is NULL");
4982         base = trunc_page(va);
4983
4984         while (count) {
4985                 pte = vtopte(va);
4986                 *pte = (*pte & ~(pt_entry_t)(kernel_pmap.pmap_cache_mask)) |
4987                        kernel_pmap.pmap_cache_bits[mode];
4988                 --count;
4989                 va += PAGE_SIZE;
4990         }
4991
4992         changed = 1;    /* XXX: not optimal */
4993
4994         /*
4995          * Flush CPU caches if required to make sure any data isn't cached that
4996          * shouldn't be, etc.
4997          */
4998         if (changed) {
4999                 pmap_invalidate_range(&kernel_pmap, base, va);
5000                 pmap_invalidate_cache_range(base, va);
5001         }
5002 }
5003
5004 /*
5005  * perform the pmap work for mincore
5006  */
5007 int
5008 pmap_mincore(pmap_t pmap, vm_offset_t addr)
5009 {
5010         pt_entry_t *ptep, pte;
5011         vm_page_t m;
5012         int val = 0;
5013         
5014         lwkt_gettoken(&pmap->pm_token);
5015         ptep = pmap_pte(pmap, addr);
5016
5017         if (ptep && (pte = *ptep) != 0) {
5018                 vm_offset_t pa;
5019
5020                 val = MINCORE_INCORE;
5021                 if ((pte & pmap->pmap_bits[PG_MANAGED_IDX]) == 0)
5022                         goto done;
5023
5024                 pa = pte & PG_FRAME;
5025
5026                 if (pte & pmap->pmap_bits[PG_DEVICE_IDX])
5027                         m = NULL;
5028                 else
5029                         m = PHYS_TO_VM_PAGE(pa);
5030
5031                 /*
5032                  * Modified by us
5033                  */
5034                 if (pte & pmap->pmap_bits[PG_M_IDX])
5035                         val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER;
5036                 /*
5037                  * Modified by someone
5038                  */
5039                 else if (m && (m->dirty || pmap_is_modified(m)))
5040                         val |= MINCORE_MODIFIED_OTHER;
5041                 /*
5042                  * Referenced by us
5043                  */
5044                 if (pte & pmap->pmap_bits[PG_A_IDX])
5045                         val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER;
5046
5047                 /*
5048                  * Referenced by someone
5049                  */
5050                 else if (m && ((m->flags & PG_REFERENCED) ||
5051                                 pmap_ts_referenced(m))) {
5052                         val |= MINCORE_REFERENCED_OTHER;
5053                         vm_page_flag_set(m, PG_REFERENCED);
5054                 }
5055         } 
5056 done:
5057         lwkt_reltoken(&pmap->pm_token);
5058
5059         return val;
5060 }
5061
5062 /*
5063  * Replace p->p_vmspace with a new one.  If adjrefs is non-zero the new
5064  * vmspace will be ref'd and the old one will be deref'd.
5065  *
5066  * The vmspace for all lwps associated with the process will be adjusted
5067  * and cr3 will be reloaded if any lwp is the current lwp.
5068  *
5069  * The process must hold the vmspace->vm_map.token for oldvm and newvm
5070  */
5071 void
5072 pmap_replacevm(struct proc *p, struct vmspace *newvm, int adjrefs)
5073 {
5074         struct vmspace *oldvm;
5075         struct lwp *lp;
5076
5077         oldvm = p->p_vmspace;
5078         if (oldvm != newvm) {
5079                 if (adjrefs)
5080                         sysref_get(&newvm->vm_sysref);
5081                 p->p_vmspace = newvm;
5082                 KKASSERT(p->p_nthreads == 1);
5083                 lp = RB_ROOT(&p->p_lwp_tree);
5084                 pmap_setlwpvm(lp, newvm);
5085                 if (adjrefs)
5086                         sysref_put(&oldvm->vm_sysref);
5087         }
5088 }
5089
5090 /*
5091  * Set the vmspace for a LWP.  The vmspace is almost universally set the
5092  * same as the process vmspace, but virtual kernels need to swap out contexts
5093  * on a per-lwp basis.
5094  *
5095  * Caller does not necessarily hold any vmspace tokens.  Caller must control
5096  * the lwp (typically be in the context of the lwp).  We use a critical
5097  * section to protect against statclock and hardclock (statistics collection).
5098  */
5099 void
5100 pmap_setlwpvm(struct lwp *lp, struct vmspace *newvm)
5101 {
5102         struct vmspace *oldvm;
5103         struct pmap *pmap;
5104
5105         oldvm = lp->lwp_vmspace;
5106
5107         if (oldvm != newvm) {
5108                 crit_enter();
5109                 lp->lwp_vmspace = newvm;
5110                 if (curthread->td_lwp == lp) {
5111                         pmap = vmspace_pmap(newvm);
5112                         atomic_set_cpumask(&pmap->pm_active, mycpu->gd_cpumask);
5113                         if (pmap->pm_active & CPUMASK_LOCK)
5114                                 pmap_interlock_wait(newvm);
5115 #if defined(SWTCH_OPTIM_STATS)
5116                         tlb_flush_count++;
5117 #endif
5118                         if (pmap->pmap_bits[TYPE_IDX] == REGULAR_PMAP) {
5119                                 curthread->td_pcb->pcb_cr3 = vtophys(pmap->pm_pml4);
5120                         } else if (pmap->pmap_bits[TYPE_IDX] == EPT_PMAP) {
5121                                 curthread->td_pcb->pcb_cr3 = KPML4phys;
5122                         } else {
5123                                 panic("pmap_setlwpvm: unknown pmap type\n");
5124                         }
5125                         load_cr3(curthread->td_pcb->pcb_cr3);
5126                         pmap = vmspace_pmap(oldvm);
5127                         atomic_clear_cpumask(&pmap->pm_active, mycpu->gd_cpumask);
5128                 }
5129                 crit_exit();
5130         }
5131 }
5132
5133 /*
5134  * Called when switching to a locked pmap, used to interlock against pmaps
5135  * undergoing modifications to prevent us from activating the MMU for the
5136  * target pmap until all such modifications have completed.  We have to do
5137  * this because the thread making the modifications has already set up its
5138  * SMP synchronization mask.
5139  *
5140  * This function cannot sleep!
5141  *
5142  * No requirements.
5143  */
5144 void
5145 pmap_interlock_wait(struct vmspace *vm)
5146 {
5147         struct pmap *pmap = &vm->vm_pmap;
5148
5149         if (pmap->pm_active & CPUMASK_LOCK) {
5150                 crit_enter();
5151                 KKASSERT(curthread->td_critcount >= 2);
5152                 DEBUG_PUSH_INFO("pmap_interlock_wait");
5153                 while (pmap->pm_active & CPUMASK_LOCK) {
5154                         cpu_ccfence();
5155                         lwkt_process_ipiq();
5156                 }
5157                 DEBUG_POP_INFO();
5158                 crit_exit();
5159         }
5160 }
5161
5162 vm_offset_t
5163 pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size)
5164 {
5165
5166         if ((obj == NULL) || (size < NBPDR) ||
5167             ((obj->type != OBJT_DEVICE) && (obj->type != OBJT_MGTDEVICE))) {
5168                 return addr;
5169         }
5170
5171         addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1);
5172         return addr;
5173 }
5174
5175 /*
5176  * Used by kmalloc/kfree, page already exists at va
5177  */
5178 vm_page_t
5179 pmap_kvtom(vm_offset_t va)
5180 {
5181         pt_entry_t *ptep = vtopte(va);
5182
5183         KKASSERT((*ptep & kernel_pmap.pmap_bits[PG_DEVICE_IDX]) == 0);
5184         return(PHYS_TO_VM_PAGE(*ptep & PG_FRAME));
5185 }
5186
5187 /*
5188  * Initialize machine-specific shared page directory support.  This
5189  * is executed when a VM object is created.
5190  */
5191 void
5192 pmap_object_init(vm_object_t object)
5193 {
5194         object->md.pmap_rw = NULL;
5195         object->md.pmap_ro = NULL;
5196 }
5197
5198 /*
5199  * Clean up machine-specific shared page directory support.  This
5200  * is executed when a VM object is destroyed.
5201  */
5202 void
5203 pmap_object_free(vm_object_t object)
5204 {
5205         pmap_t pmap;
5206
5207         if ((pmap = object->md.pmap_rw) != NULL) {
5208                 object->md.pmap_rw = NULL;
5209                 pmap_remove_noinval(pmap,
5210                                   VM_MIN_USER_ADDRESS, VM_MAX_USER_ADDRESS);
5211                 pmap->pm_active = 0;
5212                 pmap_release(pmap);
5213                 pmap_puninit(pmap);
5214                 kfree(pmap, M_OBJPMAP);
5215         }
5216         if ((pmap = object->md.pmap_ro) != NULL) {
5217                 object->md.pmap_ro = NULL;
5218                 pmap_remove_noinval(pmap,
5219                                   VM_MIN_USER_ADDRESS, VM_MAX_USER_ADDRESS);
5220                 pmap->pm_active = 0;
5221                 pmap_release(pmap);
5222                 pmap_puninit(pmap);
5223                 kfree(pmap, M_OBJPMAP);
5224         }
5225 }