FreeBSD/Linux Kernel Cross Reference
sys/amd64/amd64/pmap.c
1 /*-
2 * Copyright (c) 1991 Regents of the University of California.
3 * All rights reserved.
4 * Copyright (c) 1994 John S. Dyson
5 * All rights reserved.
6 * Copyright (c) 1994 David Greenman
7 * All rights reserved.
8 * Copyright (c) 2003 Peter Wemm
9 * All rights reserved.
10 * Copyright (c) 2005 Alan L. Cox <alc@cs.rice.edu>
11 * All rights reserved.
12 *
13 * This code is derived from software contributed to Berkeley by
14 * the Systems Programming Group of the University of Utah Computer
15 * Science Department and William Jolitz of UUNET Technologies Inc.
16 *
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions
19 * are met:
20 * 1. Redistributions of source code must retain the above copyright
21 * notice, this list of conditions and the following disclaimer.
22 * 2. Redistributions in binary form must reproduce the above copyright
23 * notice, this list of conditions and the following disclaimer in the
24 * documentation and/or other materials provided with the distribution.
25 * 3. All advertising materials mentioning features or use of this software
26 * must display the following acknowledgement:
27 * This product includes software developed by the University of
28 * California, Berkeley and its contributors.
29 * 4. Neither the name of the University nor the names of its contributors
30 * may be used to endorse or promote products derived from this software
31 * without specific prior written permission.
32 *
33 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
34 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
35 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
36 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
37 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
38 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
39 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
41 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
42 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
43 * SUCH DAMAGE.
44 *
45 * from: @(#)pmap.c 7.7 (Berkeley) 5/12/91
46 */
47 /*-
48 * Copyright (c) 2003 Networks Associates Technology, Inc.
49 * All rights reserved.
50 *
51 * This software was developed for the FreeBSD Project by Jake Burkholder,
52 * Safeport Network Services, and Network Associates Laboratories, the
53 * Security Research Division of Network Associates, Inc. under
54 * DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA
55 * CHATS research program.
56 *
57 * Redistribution and use in source and binary forms, with or without
58 * modification, are permitted provided that the following conditions
59 * are met:
60 * 1. Redistributions of source code must retain the above copyright
61 * notice, this list of conditions and the following disclaimer.
62 * 2. Redistributions in binary form must reproduce the above copyright
63 * notice, this list of conditions and the following disclaimer in the
64 * documentation and/or other materials provided with the distribution.
65 *
66 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
67 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
68 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
69 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
70 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
71 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
72 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
73 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
74 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
75 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
76 * SUCH DAMAGE.
77 */
78
79 #include <sys/cdefs.h>
80 __FBSDID("$FreeBSD$");
81
82 /*
83 * Manages physical address maps.
84 *
85 * In addition to hardware address maps, this
86 * module is called upon to provide software-use-only
87 * maps which may or may not be stored in the same
88 * form as hardware maps. These pseudo-maps are
89 * used to store intermediate results from copy
90 * operations to and from address spaces.
91 *
92 * Since the information managed by this module is
93 * also stored by the logical address mapping module,
94 * this module may throw away valid virtual-to-physical
95 * mappings at almost any time. However, invalidations
96 * of virtual-to-physical mappings must be done as
97 * requested.
98 *
99 * In order to cope with hardware architectures which
100 * make virtual-to-physical map invalidates expensive,
101 * this module may delay invalidate or reduced protection
102 * operations until such time as they are actually
103 * necessary. This module is given full information as
104 * to which processors are currently using which maps,
105 * and to when physical maps must be made correct.
106 */
107
108 #include "opt_msgbuf.h"
109 #include "opt_pmap.h"
110
111 #include <sys/param.h>
112 #include <sys/systm.h>
113 #include <sys/kernel.h>
114 #include <sys/lock.h>
115 #include <sys/malloc.h>
116 #include <sys/mman.h>
117 #include <sys/msgbuf.h>
118 #include <sys/mutex.h>
119 #include <sys/proc.h>
120 #include <sys/sx.h>
121 #include <sys/vmmeter.h>
122 #include <sys/sched.h>
123 #include <sys/sysctl.h>
124 #ifdef SMP
125 #include <sys/smp.h>
126 #endif
127
128 #include <vm/vm.h>
129 #include <vm/vm_param.h>
130 #include <vm/vm_kern.h>
131 #include <vm/vm_page.h>
132 #include <vm/vm_map.h>
133 #include <vm/vm_object.h>
134 #include <vm/vm_extern.h>
135 #include <vm/vm_pageout.h>
136 #include <vm/vm_pager.h>
137 #include <vm/uma.h>
138
139 #include <machine/cpu.h>
140 #include <machine/cputypes.h>
141 #include <machine/md_var.h>
142 #include <machine/pcb.h>
143 #include <machine/specialreg.h>
144 #ifdef SMP
145 #include <machine/smp.h>
146 #endif
147
148 #ifndef PMAP_SHPGPERPROC
149 #define PMAP_SHPGPERPROC 200
150 #endif
151
152 #if defined(DIAGNOSTIC)
153 #define PMAP_DIAGNOSTIC
154 #endif
155
156 #if !defined(PMAP_DIAGNOSTIC)
157 #define PMAP_INLINE __gnu89_inline
158 #else
159 #define PMAP_INLINE
160 #endif
161
162 #define PV_STATS
163 #ifdef PV_STATS
164 #define PV_STAT(x) do { x ; } while (0)
165 #else
166 #define PV_STAT(x) do { } while (0)
167 #endif
168
169 struct pmap kernel_pmap_store;
170
171 vm_offset_t virtual_avail; /* VA of first avail page (after kernel bss) */
172 vm_offset_t virtual_end; /* VA of last avail page (end of kernel AS) */
173
174 static int nkpt;
175 static int ndmpdp;
176 static vm_paddr_t dmaplimit;
177 vm_offset_t kernel_vm_end;
178 pt_entry_t pg_nx;
179
180 static u_int64_t KPTphys; /* phys addr of kernel level 1 */
181 static u_int64_t KPDphys; /* phys addr of kernel level 2 */
182 u_int64_t KPDPphys; /* phys addr of kernel level 3 */
183 u_int64_t KPML4phys; /* phys addr of kernel level 4 */
184
185 static u_int64_t DMPDphys; /* phys addr of direct mapped level 2 */
186 static u_int64_t DMPDPphys; /* phys addr of direct mapped level 3 */
187
188 /*
189 * Data for the pv entry allocation mechanism
190 */
191 static int pv_entry_count = 0, pv_entry_max = 0, pv_entry_high_water = 0;
192 static int shpgperproc = PMAP_SHPGPERPROC;
193
194 /*
195 * All those kernel PT submaps that BSD is so fond of
196 */
197 pt_entry_t *CMAP1 = 0;
198 caddr_t CADDR1 = 0;
199 struct msgbuf *msgbufp = 0;
200
201 /*
202 * Crashdump maps.
203 */
204 static caddr_t crashdumpmap;
205
206 static void free_pv_entry(pmap_t pmap, pv_entry_t pv);
207 static pv_entry_t get_pv_entry(pmap_t locked_pmap, int try);
208
209 static vm_page_t pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va,
210 vm_page_t m, vm_prot_t prot, vm_page_t mpte);
211 static int pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq,
212 vm_offset_t sva, pd_entry_t ptepde, vm_page_t *free);
213 static void pmap_remove_page(pmap_t pmap, vm_offset_t va, pd_entry_t *pde,
214 vm_page_t *free);
215 static void pmap_remove_entry(struct pmap *pmap, vm_page_t m,
216 vm_offset_t va);
217 static void pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t m);
218 static boolean_t pmap_try_insert_pv_entry(pmap_t pmap, vm_offset_t va,
219 vm_page_t m);
220
221 static vm_page_t pmap_allocpde(pmap_t pmap, vm_offset_t va, int flags);
222 static vm_page_t pmap_allocpte(pmap_t pmap, vm_offset_t va, int flags);
223
224 static vm_page_t _pmap_allocpte(pmap_t pmap, vm_pindex_t ptepindex, int flags);
225 static int _pmap_unwire_pte_hold(pmap_t pmap, vm_offset_t va, vm_page_t m,
226 vm_page_t* free);
227 static int pmap_unuse_pt(pmap_t, vm_offset_t, pd_entry_t, vm_page_t *);
228 static vm_offset_t pmap_kmem_choose(vm_offset_t addr);
229
230 CTASSERT(1 << PDESHIFT == sizeof(pd_entry_t));
231 CTASSERT(1 << PTESHIFT == sizeof(pt_entry_t));
232
233 /*
234 * Move the kernel virtual free pointer to the next
235 * 2MB. This is used to help improve performance
236 * by using a large (2MB) page for much of the kernel
237 * (.text, .data, .bss)
238 */
239 static vm_offset_t
240 pmap_kmem_choose(vm_offset_t addr)
241 {
242 vm_offset_t newaddr = addr;
243
244 newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1);
245 return newaddr;
246 }
247
248 /********************/
249 /* Inline functions */
250 /********************/
251
252 /* Return a non-clipped PD index for a given VA */
253 static __inline vm_pindex_t
254 pmap_pde_pindex(vm_offset_t va)
255 {
256 return va >> PDRSHIFT;
257 }
258
259
260 /* Return various clipped indexes for a given VA */
261 static __inline vm_pindex_t
262 pmap_pte_index(vm_offset_t va)
263 {
264
265 return ((va >> PAGE_SHIFT) & ((1ul << NPTEPGSHIFT) - 1));
266 }
267
268 static __inline vm_pindex_t
269 pmap_pde_index(vm_offset_t va)
270 {
271
272 return ((va >> PDRSHIFT) & ((1ul << NPDEPGSHIFT) - 1));
273 }
274
275 static __inline vm_pindex_t
276 pmap_pdpe_index(vm_offset_t va)
277 {
278
279 return ((va >> PDPSHIFT) & ((1ul << NPDPEPGSHIFT) - 1));
280 }
281
282 static __inline vm_pindex_t
283 pmap_pml4e_index(vm_offset_t va)
284 {
285
286 return ((va >> PML4SHIFT) & ((1ul << NPML4EPGSHIFT) - 1));
287 }
288
289 /* Return a pointer to the PML4 slot that corresponds to a VA */
290 static __inline pml4_entry_t *
291 pmap_pml4e(pmap_t pmap, vm_offset_t va)
292 {
293
294 if (!pmap)
295 return NULL;
296 return (&pmap->pm_pml4[pmap_pml4e_index(va)]);
297 }
298
299 /* Return a pointer to the PDP slot that corresponds to a VA */
300 static __inline pdp_entry_t *
301 pmap_pml4e_to_pdpe(pml4_entry_t *pml4e, vm_offset_t va)
302 {
303 pdp_entry_t *pdpe;
304
305 pdpe = (pdp_entry_t *)PHYS_TO_DMAP(*pml4e & PG_FRAME);
306 return (&pdpe[pmap_pdpe_index(va)]);
307 }
308
309 /* Return a pointer to the PDP slot that corresponds to a VA */
310 static __inline pdp_entry_t *
311 pmap_pdpe(pmap_t pmap, vm_offset_t va)
312 {
313 pml4_entry_t *pml4e;
314
315 pml4e = pmap_pml4e(pmap, va);
316 if (pml4e == NULL || (*pml4e & PG_V) == 0)
317 return NULL;
318 return (pmap_pml4e_to_pdpe(pml4e, va));
319 }
320
321 /* Return a pointer to the PD slot that corresponds to a VA */
322 static __inline pd_entry_t *
323 pmap_pdpe_to_pde(pdp_entry_t *pdpe, vm_offset_t va)
324 {
325 pd_entry_t *pde;
326
327 pde = (pd_entry_t *)PHYS_TO_DMAP(*pdpe & PG_FRAME);
328 return (&pde[pmap_pde_index(va)]);
329 }
330
331 /* Return a pointer to the PD slot that corresponds to a VA */
332 static __inline pd_entry_t *
333 pmap_pde(pmap_t pmap, vm_offset_t va)
334 {
335 pdp_entry_t *pdpe;
336
337 pdpe = pmap_pdpe(pmap, va);
338 if (pdpe == NULL || (*pdpe & PG_V) == 0)
339 return NULL;
340 return (pmap_pdpe_to_pde(pdpe, va));
341 }
342
343 /* Return a pointer to the PT slot that corresponds to a VA */
344 static __inline pt_entry_t *
345 pmap_pde_to_pte(pd_entry_t *pde, vm_offset_t va)
346 {
347 pt_entry_t *pte;
348
349 pte = (pt_entry_t *)PHYS_TO_DMAP(*pde & PG_FRAME);
350 return (&pte[pmap_pte_index(va)]);
351 }
352
353 /* Return a pointer to the PT slot that corresponds to a VA */
354 static __inline pt_entry_t *
355 pmap_pte(pmap_t pmap, vm_offset_t va)
356 {
357 pd_entry_t *pde;
358
359 pde = pmap_pde(pmap, va);
360 if (pde == NULL || (*pde & PG_V) == 0)
361 return NULL;
362 if ((*pde & PG_PS) != 0) /* compat with i386 pmap_pte() */
363 return ((pt_entry_t *)pde);
364 return (pmap_pde_to_pte(pde, va));
365 }
366
367
368 static __inline pt_entry_t *
369 pmap_pte_pde(pmap_t pmap, vm_offset_t va, pd_entry_t *ptepde)
370 {
371 pd_entry_t *pde;
372
373 pde = pmap_pde(pmap, va);
374 if (pde == NULL || (*pde & PG_V) == 0)
375 return NULL;
376 *ptepde = *pde;
377 if ((*pde & PG_PS) != 0) /* compat with i386 pmap_pte() */
378 return ((pt_entry_t *)pde);
379 return (pmap_pde_to_pte(pde, va));
380 }
381
382
383 PMAP_INLINE pt_entry_t *
384 vtopte(vm_offset_t va)
385 {
386 u_int64_t mask = ((1ul << (NPTEPGSHIFT + NPDEPGSHIFT + NPDPEPGSHIFT + NPML4EPGSHIFT)) - 1);
387
388 return (PTmap + ((va >> PAGE_SHIFT) & mask));
389 }
390
391 static __inline pd_entry_t *
392 vtopde(vm_offset_t va)
393 {
394 u_int64_t mask = ((1ul << (NPDEPGSHIFT + NPDPEPGSHIFT + NPML4EPGSHIFT)) - 1);
395
396 return (PDmap + ((va >> PDRSHIFT) & mask));
397 }
398
399 static u_int64_t
400 allocpages(vm_paddr_t *firstaddr, int n)
401 {
402 u_int64_t ret;
403
404 ret = *firstaddr;
405 bzero((void *)ret, n * PAGE_SIZE);
406 *firstaddr += n * PAGE_SIZE;
407 return (ret);
408 }
409
410 static void
411 create_pagetables(vm_paddr_t *firstaddr)
412 {
413 int i;
414
415 /* Allocate pages */
416 KPTphys = allocpages(firstaddr, NKPT);
417 KPML4phys = allocpages(firstaddr, 1);
418 KPDPphys = allocpages(firstaddr, NKPML4E);
419 KPDphys = allocpages(firstaddr, NKPDPE);
420
421 ndmpdp = (ptoa(Maxmem) + NBPDP - 1) >> PDPSHIFT;
422 if (ndmpdp < 4) /* Minimum 4GB of dirmap */
423 ndmpdp = 4;
424 DMPDPphys = allocpages(firstaddr, NDMPML4E);
425 DMPDphys = allocpages(firstaddr, ndmpdp);
426 dmaplimit = (vm_paddr_t)ndmpdp << PDPSHIFT;
427
428 /* Fill in the underlying page table pages */
429 /* Read-only from zero to physfree */
430 /* XXX not fully used, underneath 2M pages */
431 for (i = 0; (i << PAGE_SHIFT) < *firstaddr; i++) {
432 ((pt_entry_t *)KPTphys)[i] = i << PAGE_SHIFT;
433 ((pt_entry_t *)KPTphys)[i] |= PG_RW | PG_V | PG_G;
434 }
435
436 /* Now map the page tables at their location within PTmap */
437 for (i = 0; i < NKPT; i++) {
438 ((pd_entry_t *)KPDphys)[i] = KPTphys + (i << PAGE_SHIFT);
439 ((pd_entry_t *)KPDphys)[i] |= PG_RW | PG_V;
440 }
441
442 /* Map from zero to end of allocations under 2M pages */
443 /* This replaces some of the KPTphys entries above */
444 for (i = 0; (i << PDRSHIFT) < *firstaddr; i++) {
445 ((pd_entry_t *)KPDphys)[i] = i << PDRSHIFT;
446 ((pd_entry_t *)KPDphys)[i] |= PG_RW | PG_V | PG_PS | PG_G;
447 }
448
449 /* And connect up the PD to the PDP */
450 for (i = 0; i < NKPDPE; i++) {
451 ((pdp_entry_t *)KPDPphys)[i + KPDPI] = KPDphys + (i << PAGE_SHIFT);
452 ((pdp_entry_t *)KPDPphys)[i + KPDPI] |= PG_RW | PG_V | PG_U;
453 }
454
455
456 /* Now set up the direct map space using 2MB pages */
457 for (i = 0; i < NPDEPG * ndmpdp; i++) {
458 ((pd_entry_t *)DMPDphys)[i] = (vm_paddr_t)i << PDRSHIFT;
459 ((pd_entry_t *)DMPDphys)[i] |= PG_RW | PG_V | PG_PS | PG_G;
460 }
461
462 /* And the direct map space's PDP */
463 for (i = 0; i < ndmpdp; i++) {
464 ((pdp_entry_t *)DMPDPphys)[i] = DMPDphys + (i << PAGE_SHIFT);
465 ((pdp_entry_t *)DMPDPphys)[i] |= PG_RW | PG_V | PG_U;
466 }
467
468 /* And recursively map PML4 to itself in order to get PTmap */
469 ((pdp_entry_t *)KPML4phys)[PML4PML4I] = KPML4phys;
470 ((pdp_entry_t *)KPML4phys)[PML4PML4I] |= PG_RW | PG_V | PG_U;
471
472 /* Connect the Direct Map slot up to the PML4 */
473 ((pdp_entry_t *)KPML4phys)[DMPML4I] = DMPDPphys;
474 ((pdp_entry_t *)KPML4phys)[DMPML4I] |= PG_RW | PG_V | PG_U;
475
476 /* Connect the KVA slot up to the PML4 */
477 ((pdp_entry_t *)KPML4phys)[KPML4I] = KPDPphys;
478 ((pdp_entry_t *)KPML4phys)[KPML4I] |= PG_RW | PG_V | PG_U;
479 }
480
481 /*
482 * Bootstrap the system enough to run with virtual memory.
483 *
484 * On amd64 this is called after mapping has already been enabled
485 * and just syncs the pmap module with what has already been done.
486 * [We can't call it easily with mapping off since the kernel is not
487 * mapped with PA == VA, hence we would have to relocate every address
488 * from the linked base (virtual) address "KERNBASE" to the actual
489 * (physical) address starting relative to 0]
490 */
491 void
492 pmap_bootstrap(vm_paddr_t *firstaddr)
493 {
494 vm_offset_t va;
495 pt_entry_t *pte, *unused;
496
497 /*
498 * Create an initial set of page tables to run the kernel in.
499 */
500 create_pagetables(firstaddr);
501
502 virtual_avail = (vm_offset_t) KERNBASE + *firstaddr;
503 virtual_avail = pmap_kmem_choose(virtual_avail);
504
505 virtual_end = VM_MAX_KERNEL_ADDRESS;
506
507
508 /* XXX do %cr0 as well */
509 load_cr4(rcr4() | CR4_PGE | CR4_PSE);
510 load_cr3(KPML4phys);
511
512 /*
513 * Initialize the kernel pmap (which is statically allocated).
514 */
515 PMAP_LOCK_INIT(kernel_pmap);
516 kernel_pmap->pm_pml4 = (pdp_entry_t *) (KERNBASE + KPML4phys);
517 kernel_pmap->pm_active = -1; /* don't allow deactivation */
518 TAILQ_INIT(&kernel_pmap->pm_pvchunk);
519 nkpt = NKPT;
520
521 /*
522 * Reserve some special page table entries/VA space for temporary
523 * mapping of pages.
524 */
525 #define SYSMAP(c, p, v, n) \
526 v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n);
527
528 va = virtual_avail;
529 pte = vtopte(va);
530
531 /*
532 * CMAP1 is only used for the memory test.
533 */
534 SYSMAP(caddr_t, CMAP1, CADDR1, 1)
535
536 /*
537 * Crashdump maps.
538 */
539 SYSMAP(caddr_t, unused, crashdumpmap, MAXDUMPPGS)
540
541 /*
542 * msgbufp is used to map the system message buffer.
543 */
544 SYSMAP(struct msgbuf *, unused, msgbufp, atop(round_page(MSGBUF_SIZE)))
545
546 virtual_avail = va;
547
548 *CMAP1 = 0;
549
550 invltlb();
551
552 /* Initialize the PAT MSR. */
553 pmap_init_pat();
554 }
555
556 /*
557 * Setup the PAT MSR.
558 */
559 void
560 pmap_init_pat(void)
561 {
562 uint64_t pat_msr;
563
564 /* Bail if this CPU doesn't implement PAT. */
565 if (!(cpu_feature & CPUID_PAT))
566 panic("no PAT??");
567
568 #ifdef PAT_WORKS
569 /*
570 * Leave the indices 0-3 at the default of WB, WT, UC, and UC-.
571 * Program 4 and 5 as WP and WC.
572 * Leave 6 and 7 as UC and UC-.
573 */
574 pat_msr = rdmsr(MSR_PAT);
575 pat_msr &= ~(PAT_MASK(4) | PAT_MASK(5));
576 pat_msr |= PAT_VALUE(4, PAT_WRITE_PROTECTED) |
577 PAT_VALUE(5, PAT_WRITE_COMBINING);
578 #else
579 /*
580 * Due to some Intel errata, we can only safely use the lower 4
581 * PAT entries. Thus, just replace PAT Index 2 with WC instead
582 * of UC-.
583 *
584 * Intel Pentium III Processor Specification Update
585 * Errata E.27 (Upper Four PAT Entries Not Usable With Mode B
586 * or Mode C Paging)
587 *
588 * Intel Pentium IV Processor Specification Update
589 * Errata N46 (PAT Index MSB May Be Calculated Incorrectly)
590 */
591 pat_msr = rdmsr(MSR_PAT);
592 pat_msr &= ~PAT_MASK(2);
593 pat_msr |= PAT_VALUE(2, PAT_WRITE_COMBINING);
594 #endif
595 wrmsr(MSR_PAT, pat_msr);
596 }
597
598 /*
599 * Initialize a vm_page's machine-dependent fields.
600 */
601 void
602 pmap_page_init(vm_page_t m)
603 {
604
605 TAILQ_INIT(&m->md.pv_list);
606 m->md.pv_list_count = 0;
607 }
608
609 /*
610 * Initialize the pmap module.
611 * Called by vm_init, to initialize any structures that the pmap
612 * system needs to map virtual memory.
613 */
614 void
615 pmap_init(void)
616 {
617
618 /*
619 * Initialize the address space (zone) for the pv entries. Set a
620 * high water mark so that the system can recover from excessive
621 * numbers of pv entries.
622 */
623 TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc);
624 pv_entry_max = shpgperproc * maxproc + cnt.v_page_count;
625 TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max);
626 pv_entry_high_water = 9 * (pv_entry_max / 10);
627 }
628
629 SYSCTL_NODE(_vm, OID_AUTO, pmap, CTLFLAG_RD, 0, "VM/pmap parameters");
630 static int
631 pmap_pventry_proc(SYSCTL_HANDLER_ARGS)
632 {
633 int error;
634
635 error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req);
636 if (error == 0 && req->newptr) {
637 shpgperproc = (pv_entry_max - cnt.v_page_count) / maxproc;
638 pv_entry_high_water = 9 * (pv_entry_max / 10);
639 }
640 return (error);
641 }
642 SYSCTL_PROC(_vm_pmap, OID_AUTO, pv_entry_max, CTLTYPE_INT|CTLFLAG_RW,
643 &pv_entry_max, 0, pmap_pventry_proc, "IU", "Max number of PV entries");
644
645 static int
646 pmap_shpgperproc_proc(SYSCTL_HANDLER_ARGS)
647 {
648 int error;
649
650 error = sysctl_handle_int(oidp, oidp->oid_arg1, oidp->oid_arg2, req);
651 if (error == 0 && req->newptr) {
652 pv_entry_max = shpgperproc * maxproc + cnt.v_page_count;
653 pv_entry_high_water = 9 * (pv_entry_max / 10);
654 }
655 return (error);
656 }
657 SYSCTL_PROC(_vm_pmap, OID_AUTO, shpgperproc, CTLTYPE_INT|CTLFLAG_RW,
658 &shpgperproc, 0, pmap_shpgperproc_proc, "IU", "Page share factor per proc");
659
660
661 /***************************************************
662 * Low level helper routines.....
663 ***************************************************/
664
665 /*
666 * Determine the appropriate bits to set in a PTE or PDE for a specified
667 * caching mode.
668 */
669 static int
670 pmap_cache_bits(int mode, boolean_t is_pde)
671 {
672 int pat_flag, pat_index, cache_bits;
673
674 /* The PAT bit is different for PTE's and PDE's. */
675 pat_flag = is_pde ? PG_PDE_PAT : PG_PTE_PAT;
676
677 /* If we don't support PAT, map extended modes to older ones. */
678 if (!(cpu_feature & CPUID_PAT)) {
679 switch (mode) {
680 case PAT_UNCACHEABLE:
681 case PAT_WRITE_THROUGH:
682 case PAT_WRITE_BACK:
683 break;
684 case PAT_UNCACHED:
685 case PAT_WRITE_COMBINING:
686 case PAT_WRITE_PROTECTED:
687 mode = PAT_UNCACHEABLE;
688 break;
689 }
690 }
691
692 /* Map the caching mode to a PAT index. */
693 switch (mode) {
694 #ifdef PAT_WORKS
695 case PAT_UNCACHEABLE:
696 pat_index = 3;
697 break;
698 case PAT_WRITE_THROUGH:
699 pat_index = 1;
700 break;
701 case PAT_WRITE_BACK:
702 pat_index = 0;
703 break;
704 case PAT_UNCACHED:
705 pat_index = 2;
706 break;
707 case PAT_WRITE_COMBINING:
708 pat_index = 5;
709 break;
710 case PAT_WRITE_PROTECTED:
711 pat_index = 4;
712 break;
713 #else
714 case PAT_UNCACHED:
715 case PAT_UNCACHEABLE:
716 case PAT_WRITE_PROTECTED:
717 pat_index = 3;
718 break;
719 case PAT_WRITE_THROUGH:
720 pat_index = 1;
721 break;
722 case PAT_WRITE_BACK:
723 pat_index = 0;
724 break;
725 case PAT_WRITE_COMBINING:
726 pat_index = 2;
727 break;
728 #endif
729 default:
730 panic("Unknown caching mode %d\n", mode);
731 }
732
733 /* Map the 3-bit index value into the PAT, PCD, and PWT bits. */
734 cache_bits = 0;
735 if (pat_index & 0x4)
736 cache_bits |= pat_flag;
737 if (pat_index & 0x2)
738 cache_bits |= PG_NC_PCD;
739 if (pat_index & 0x1)
740 cache_bits |= PG_NC_PWT;
741 return (cache_bits);
742 }
743 #ifdef SMP
744 /*
745 * For SMP, these functions have to use the IPI mechanism for coherence.
746 *
747 * N.B.: Before calling any of the following TLB invalidation functions,
748 * the calling processor must ensure that all stores updating a non-
749 * kernel page table are globally performed. Otherwise, another
750 * processor could cache an old, pre-update entry without being
751 * invalidated. This can happen one of two ways: (1) The pmap becomes
752 * active on another processor after its pm_active field is checked by
753 * one of the following functions but before a store updating the page
754 * table is globally performed. (2) The pmap becomes active on another
755 * processor before its pm_active field is checked but due to
756 * speculative loads one of the following functions stills reads the
757 * pmap as inactive on the other processor.
758 *
759 * The kernel page table is exempt because its pm_active field is
760 * immutable. The kernel page table is always active on every
761 * processor.
762 */
763 void
764 pmap_invalidate_page(pmap_t pmap, vm_offset_t va)
765 {
766 u_int cpumask;
767 u_int other_cpus;
768
769 sched_pin();
770 if (pmap == kernel_pmap || pmap->pm_active == all_cpus) {
771 invlpg(va);
772 smp_invlpg(va);
773 } else {
774 cpumask = PCPU_GET(cpumask);
775 other_cpus = PCPU_GET(other_cpus);
776 if (pmap->pm_active & cpumask)
777 invlpg(va);
778 if (pmap->pm_active & other_cpus)
779 smp_masked_invlpg(pmap->pm_active & other_cpus, va);
780 }
781 sched_unpin();
782 }
783
784 void
785 pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
786 {
787 u_int cpumask;
788 u_int other_cpus;
789 vm_offset_t addr;
790
791 sched_pin();
792 if (pmap == kernel_pmap || pmap->pm_active == all_cpus) {
793 for (addr = sva; addr < eva; addr += PAGE_SIZE)
794 invlpg(addr);
795 smp_invlpg_range(sva, eva);
796 } else {
797 cpumask = PCPU_GET(cpumask);
798 other_cpus = PCPU_GET(other_cpus);
799 if (pmap->pm_active & cpumask)
800 for (addr = sva; addr < eva; addr += PAGE_SIZE)
801 invlpg(addr);
802 if (pmap->pm_active & other_cpus)
803 smp_masked_invlpg_range(pmap->pm_active & other_cpus,
804 sva, eva);
805 }
806 sched_unpin();
807 }
808
809 void
810 pmap_invalidate_all(pmap_t pmap)
811 {
812 u_int cpumask;
813 u_int other_cpus;
814
815 sched_pin();
816 if (pmap == kernel_pmap || pmap->pm_active == all_cpus) {
817 invltlb();
818 smp_invltlb();
819 } else {
820 cpumask = PCPU_GET(cpumask);
821 other_cpus = PCPU_GET(other_cpus);
822 if (pmap->pm_active & cpumask)
823 invltlb();
824 if (pmap->pm_active & other_cpus)
825 smp_masked_invltlb(pmap->pm_active & other_cpus);
826 }
827 sched_unpin();
828 }
829
830 void
831 pmap_invalidate_cache(void)
832 {
833
834 sched_pin();
835 wbinvd();
836 smp_cache_flush();
837 sched_unpin();
838 }
839 #else /* !SMP */
840 /*
841 * Normal, non-SMP, invalidation functions.
842 * We inline these within pmap.c for speed.
843 */
844 PMAP_INLINE void
845 pmap_invalidate_page(pmap_t pmap, vm_offset_t va)
846 {
847
848 if (pmap == kernel_pmap || pmap->pm_active)
849 invlpg(va);
850 }
851
852 PMAP_INLINE void
853 pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
854 {
855 vm_offset_t addr;
856
857 if (pmap == kernel_pmap || pmap->pm_active)
858 for (addr = sva; addr < eva; addr += PAGE_SIZE)
859 invlpg(addr);
860 }
861
862 PMAP_INLINE void
863 pmap_invalidate_all(pmap_t pmap)
864 {
865
866 if (pmap == kernel_pmap || pmap->pm_active)
867 invltlb();
868 }
869
870 PMAP_INLINE void
871 pmap_invalidate_cache(void)
872 {
873
874 wbinvd();
875 }
876 #endif /* !SMP */
877
878 /*
879 * Are we current address space or kernel?
880 */
881 static __inline int
882 pmap_is_current(pmap_t pmap)
883 {
884 return (pmap == kernel_pmap ||
885 (pmap->pm_pml4[PML4PML4I] & PG_FRAME) == (PML4pml4e[0] & PG_FRAME));
886 }
887
888 /*
889 * Routine: pmap_extract
890 * Function:
891 * Extract the physical page address associated
892 * with the given map/virtual_address pair.
893 */
894 vm_paddr_t
895 pmap_extract(pmap_t pmap, vm_offset_t va)
896 {
897 vm_paddr_t rtval;
898 pt_entry_t *pte;
899 pd_entry_t pde, *pdep;
900
901 rtval = 0;
902 PMAP_LOCK(pmap);
903 pdep = pmap_pde(pmap, va);
904 if (pdep != NULL) {
905 pde = *pdep;
906 if (pde) {
907 if ((pde & PG_PS) != 0) {
908 rtval = (pde & PG_PS_FRAME) | (va & PDRMASK);
909 PMAP_UNLOCK(pmap);
910 return rtval;
911 }
912 pte = pmap_pde_to_pte(pdep, va);
913 rtval = (*pte & PG_FRAME) | (va & PAGE_MASK);
914 }
915 }
916 PMAP_UNLOCK(pmap);
917 return (rtval);
918 }
919
920 /*
921 * Routine: pmap_extract_and_hold
922 * Function:
923 * Atomically extract and hold the physical page
924 * with the given pmap and virtual address pair
925 * if that mapping permits the given protection.
926 */
927 vm_page_t
928 pmap_extract_and_hold(pmap_t pmap, vm_offset_t va, vm_prot_t prot)
929 {
930 pd_entry_t pde, *pdep;
931 pt_entry_t pte;
932 vm_page_t m;
933
934 m = NULL;
935 vm_page_lock_queues();
936 PMAP_LOCK(pmap);
937 pdep = pmap_pde(pmap, va);
938 if (pdep != NULL && (pde = *pdep)) {
939 if (pde & PG_PS) {
940 if ((pde & PG_RW) || (prot & VM_PROT_WRITE) == 0) {
941 m = PHYS_TO_VM_PAGE((pde & PG_PS_FRAME) |
942 (va & PDRMASK));
943 vm_page_hold(m);
944 }
945 } else {
946 pte = *pmap_pde_to_pte(pdep, va);
947 if ((pte & PG_V) &&
948 ((pte & PG_RW) || (prot & VM_PROT_WRITE) == 0)) {
949 m = PHYS_TO_VM_PAGE(pte & PG_FRAME);
950 vm_page_hold(m);
951 }
952 }
953 }
954 vm_page_unlock_queues();
955 PMAP_UNLOCK(pmap);
956 return (m);
957 }
958
959 vm_paddr_t
960 pmap_kextract(vm_offset_t va)
961 {
962 pd_entry_t *pde;
963 vm_paddr_t pa;
964
965 if (va >= DMAP_MIN_ADDRESS && va < DMAP_MAX_ADDRESS) {
966 pa = DMAP_TO_PHYS(va);
967 } else {
968 pde = vtopde(va);
969 if (*pde & PG_PS) {
970 pa = (*pde & PG_PS_FRAME) | (va & PDRMASK);
971 } else {
972 pa = *vtopte(va);
973 pa = (pa & PG_FRAME) | (va & PAGE_MASK);
974 }
975 }
976 return pa;
977 }
978
979 /***************************************************
980 * Low level mapping routines.....
981 ***************************************************/
982
983 /*
984 * Add a wired page to the kva.
985 * Note: not SMP coherent.
986 */
987 PMAP_INLINE void
988 pmap_kenter(vm_offset_t va, vm_paddr_t pa)
989 {
990 pt_entry_t *pte;
991
992 pte = vtopte(va);
993 pte_store(pte, pa | PG_RW | PG_V | PG_G);
994 }
995
996 PMAP_INLINE void
997 pmap_kenter_attr(vm_offset_t va, vm_paddr_t pa, int mode)
998 {
999 pt_entry_t *pte;
1000
1001 pte = vtopte(va);
1002 pte_store(pte, pa | PG_RW | PG_V | PG_G | pmap_cache_bits(mode, 0));
1003 }
1004
1005 /*
1006 * Remove a page from the kernel pagetables.
1007 * Note: not SMP coherent.
1008 */
1009 PMAP_INLINE void
1010 pmap_kremove(vm_offset_t va)
1011 {
1012 pt_entry_t *pte;
1013
1014 pte = vtopte(va);
1015 pte_clear(pte);
1016 }
1017
1018 /*
1019 * Used to map a range of physical addresses into kernel
1020 * virtual address space.
1021 *
1022 * The value passed in '*virt' is a suggested virtual address for
1023 * the mapping. Architectures which can support a direct-mapped
1024 * physical to virtual region can return the appropriate address
1025 * within that region, leaving '*virt' unchanged. Other
1026 * architectures should map the pages starting at '*virt' and
1027 * update '*virt' with the first usable address after the mapped
1028 * region.
1029 */
1030 vm_offset_t
1031 pmap_map(vm_offset_t *virt, vm_paddr_t start, vm_paddr_t end, int prot)
1032 {
1033 return PHYS_TO_DMAP(start);
1034 }
1035
1036
1037 /*
1038 * Add a list of wired pages to the kva
1039 * this routine is only used for temporary
1040 * kernel mappings that do not need to have
1041 * page modification or references recorded.
1042 * Note that old mappings are simply written
1043 * over. The page *must* be wired.
1044 * Note: SMP coherent. Uses a ranged shootdown IPI.
1045 */
1046 void
1047 pmap_qenter(vm_offset_t sva, vm_page_t *ma, int count)
1048 {
1049 pt_entry_t *endpte, oldpte, *pte;
1050
1051 oldpte = 0;
1052 pte = vtopte(sva);
1053 endpte = pte + count;
1054 while (pte < endpte) {
1055 oldpte |= *pte;
1056 pte_store(pte, VM_PAGE_TO_PHYS(*ma) | PG_G | PG_RW | PG_V);
1057 pte++;
1058 ma++;
1059 }
1060 if ((oldpte & PG_V) != 0)
1061 pmap_invalidate_range(kernel_pmap, sva, sva + count *
1062 PAGE_SIZE);
1063 }
1064
1065 /*
1066 * This routine tears out page mappings from the
1067 * kernel -- it is meant only for temporary mappings.
1068 * Note: SMP coherent. Uses a ranged shootdown IPI.
1069 */
1070 void
1071 pmap_qremove(vm_offset_t sva, int count)
1072 {
1073 vm_offset_t va;
1074
1075 va = sva;
1076 while (count-- > 0) {
1077 pmap_kremove(va);
1078 va += PAGE_SIZE;
1079 }
1080 pmap_invalidate_range(kernel_pmap, sva, va);
1081 }
1082
1083 /***************************************************
1084 * Page table page management routines.....
1085 ***************************************************/
1086 static __inline void
1087 pmap_free_zero_pages(vm_page_t free)
1088 {
1089 vm_page_t m;
1090
1091 while (free != NULL) {
1092 m = free;
1093 free = m->right;
1094 vm_page_free_zero(m);
1095 }
1096 }
1097
1098 /*
1099 * This routine unholds page table pages, and if the hold count
1100 * drops to zero, then it decrements the wire count.
1101 */
1102 static __inline int
1103 pmap_unwire_pte_hold(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t *free)
1104 {
1105
1106 --m->wire_count;
1107 if (m->wire_count == 0)
1108 return _pmap_unwire_pte_hold(pmap, va, m, free);
1109 else
1110 return 0;
1111 }
1112
1113 static int
1114 _pmap_unwire_pte_hold(pmap_t pmap, vm_offset_t va, vm_page_t m,
1115 vm_page_t *free)
1116 {
1117 vm_offset_t pteva;
1118
1119 /*
1120 * unmap the page table page
1121 */
1122 if (m->pindex >= (NUPDE + NUPDPE)) {
1123 /* PDP page */
1124 pml4_entry_t *pml4;
1125 pml4 = pmap_pml4e(pmap, va);
1126 pteva = (vm_offset_t) PDPmap + amd64_ptob(m->pindex - (NUPDE + NUPDPE));
1127 *pml4 = 0;
1128 } else if (m->pindex >= NUPDE) {
1129 /* PD page */
1130 pdp_entry_t *pdp;
1131 pdp = pmap_pdpe(pmap, va);
1132 pteva = (vm_offset_t) PDmap + amd64_ptob(m->pindex - NUPDE);
1133 *pdp = 0;
1134 } else {
1135 /* PTE page */
1136 pd_entry_t *pd;
1137 pd = pmap_pde(pmap, va);
1138 pteva = (vm_offset_t) PTmap + amd64_ptob(m->pindex);
1139 *pd = 0;
1140 }
1141 --pmap->pm_stats.resident_count;
1142 if (m->pindex < NUPDE) {
1143 /* We just released a PT, unhold the matching PD */
1144 vm_page_t pdpg;
1145
1146 pdpg = PHYS_TO_VM_PAGE(*pmap_pdpe(pmap, va) & PG_FRAME);
1147 pmap_unwire_pte_hold(pmap, va, pdpg, free);
1148 }
1149 if (m->pindex >= NUPDE && m->pindex < (NUPDE + NUPDPE)) {
1150 /* We just released a PD, unhold the matching PDP */
1151 vm_page_t pdppg;
1152
1153 pdppg = PHYS_TO_VM_PAGE(*pmap_pml4e(pmap, va) & PG_FRAME);
1154 pmap_unwire_pte_hold(pmap, va, pdppg, free);
1155 }
1156
1157 /*
1158 * This is a release store so that the ordinary store unmapping
1159 * the page table page is globally performed before TLB shoot-
1160 * down is begun.
1161 */
1162 atomic_subtract_rel_int(&cnt.v_wire_count, 1);
1163
1164 /*
1165 * Do an invltlb to make the invalidated mapping
1166 * take effect immediately.
1167 */
1168 pmap_invalidate_page(pmap, pteva);
1169
1170 /*
1171 * Put page on a list so that it is released after
1172 * *ALL* TLB shootdown is done
1173 */
1174 m->right = *free;
1175 *free = m;
1176
1177 return 1;
1178 }
1179
1180 /*
1181 * After removing a page table entry, this routine is used to
1182 * conditionally free the page, and manage the hold/wire counts.
1183 */
1184 static int
1185 pmap_unuse_pt(pmap_t pmap, vm_offset_t va, pd_entry_t ptepde, vm_page_t *free)
1186 {
1187 vm_page_t mpte;
1188
1189 if (va >= VM_MAXUSER_ADDRESS)
1190 return 0;
1191 KASSERT(ptepde != 0, ("pmap_unuse_pt: ptepde != 0"));
1192 mpte = PHYS_TO_VM_PAGE(ptepde & PG_FRAME);
1193 return pmap_unwire_pte_hold(pmap, va, mpte, free);
1194 }
1195
1196 void
1197 pmap_pinit0(pmap_t pmap)
1198 {
1199
1200 PMAP_LOCK_INIT(pmap);
1201 pmap->pm_pml4 = (pml4_entry_t *)(KERNBASE + KPML4phys);
1202 pmap->pm_active = 0;
1203 TAILQ_INIT(&pmap->pm_pvchunk);
1204 bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
1205 }
1206
1207 /*
1208 * Initialize a preallocated and zeroed pmap structure,
1209 * such as one in a vmspace structure.
1210 */
1211 int
1212 pmap_pinit(pmap_t pmap)
1213 {
1214 vm_page_t pml4pg;
1215 static vm_pindex_t color;
1216
1217 PMAP_LOCK_INIT(pmap);
1218
1219 /*
1220 * allocate the page directory page
1221 */
1222 while ((pml4pg = vm_page_alloc(NULL, color++, VM_ALLOC_NOOBJ |
1223 VM_ALLOC_NORMAL | VM_ALLOC_WIRED | VM_ALLOC_ZERO)) == NULL)
1224 VM_WAIT;
1225
1226 pmap->pm_pml4 = (pml4_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(pml4pg));
1227
1228 if ((pml4pg->flags & PG_ZERO) == 0)
1229 pagezero(pmap->pm_pml4);
1230
1231 /* Wire in kernel global address entries. */
1232 pmap->pm_pml4[KPML4I] = KPDPphys | PG_RW | PG_V | PG_U;
1233 pmap->pm_pml4[DMPML4I] = DMPDPphys | PG_RW | PG_V | PG_U;
1234
1235 /* install self-referential address mapping entry(s) */
1236 pmap->pm_pml4[PML4PML4I] = VM_PAGE_TO_PHYS(pml4pg) | PG_V | PG_RW | PG_A | PG_M;
1237
1238 pmap->pm_active = 0;
1239 TAILQ_INIT(&pmap->pm_pvchunk);
1240 bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
1241
1242 return (1);
1243 }
1244
1245 /*
1246 * this routine is called if the page table page is not
1247 * mapped correctly.
1248 *
1249 * Note: If a page allocation fails at page table level two or three,
1250 * one or two pages may be held during the wait, only to be released
1251 * afterwards. This conservative approach is easily argued to avoid
1252 * race conditions.
1253 */
1254 static vm_page_t
1255 _pmap_allocpte(pmap_t pmap, vm_pindex_t ptepindex, int flags)
1256 {
1257 vm_page_t m, pdppg, pdpg;
1258
1259 KASSERT((flags & (M_NOWAIT | M_WAITOK)) == M_NOWAIT ||
1260 (flags & (M_NOWAIT | M_WAITOK)) == M_WAITOK,
1261 ("_pmap_allocpte: flags is neither M_NOWAIT nor M_WAITOK"));
1262
1263 /*
1264 * Allocate a page table page.
1265 */
1266 if ((m = vm_page_alloc(NULL, ptepindex, VM_ALLOC_NOOBJ |
1267 VM_ALLOC_WIRED | VM_ALLOC_ZERO)) == NULL) {
1268 if (flags & M_WAITOK) {
1269 PMAP_UNLOCK(pmap);
1270 vm_page_unlock_queues();
1271 VM_WAIT;
1272 vm_page_lock_queues();
1273 PMAP_LOCK(pmap);
1274 }
1275
1276 /*
1277 * Indicate the need to retry. While waiting, the page table
1278 * page may have been allocated.
1279 */
1280 return (NULL);
1281 }
1282 if ((m->flags & PG_ZERO) == 0)
1283 pmap_zero_page(m);
1284
1285 /*
1286 * Map the pagetable page into the process address space, if
1287 * it isn't already there.
1288 */
1289
1290 pmap->pm_stats.resident_count++;
1291
1292 if (ptepindex >= (NUPDE + NUPDPE)) {
1293 pml4_entry_t *pml4;
1294 vm_pindex_t pml4index;
1295
1296 /* Wire up a new PDPE page */
1297 pml4index = ptepindex - (NUPDE + NUPDPE);
1298 pml4 = &pmap->pm_pml4[pml4index];
1299 *pml4 = VM_PAGE_TO_PHYS(m) | PG_U | PG_RW | PG_V | PG_A | PG_M;
1300
1301 } else if (ptepindex >= NUPDE) {
1302 vm_pindex_t pml4index;
1303 vm_pindex_t pdpindex;
1304 pml4_entry_t *pml4;
1305 pdp_entry_t *pdp;
1306
1307 /* Wire up a new PDE page */
1308 pdpindex = ptepindex - NUPDE;
1309 pml4index = pdpindex >> NPML4EPGSHIFT;
1310
1311 pml4 = &pmap->pm_pml4[pml4index];
1312 if ((*pml4 & PG_V) == 0) {
1313 /* Have to allocate a new pdp, recurse */
1314 if (_pmap_allocpte(pmap, NUPDE + NUPDPE + pml4index,
1315 flags) == NULL) {
1316 --m->wire_count;
1317 vm_page_free(m);
1318 return (NULL);
1319 }
1320 } else {
1321 /* Add reference to pdp page */
1322 pdppg = PHYS_TO_VM_PAGE(*pml4 & PG_FRAME);
1323 pdppg->wire_count++;
1324 }
1325 pdp = (pdp_entry_t *)PHYS_TO_DMAP(*pml4 & PG_FRAME);
1326
1327 /* Now find the pdp page */
1328 pdp = &pdp[pdpindex & ((1ul << NPDPEPGSHIFT) - 1)];
1329 *pdp = VM_PAGE_TO_PHYS(m) | PG_U | PG_RW | PG_V | PG_A | PG_M;
1330
1331 } else {
1332 vm_pindex_t pml4index;
1333 vm_pindex_t pdpindex;
1334 pml4_entry_t *pml4;
1335 pdp_entry_t *pdp;
1336 pd_entry_t *pd;
1337
1338 /* Wire up a new PTE page */
1339 pdpindex = ptepindex >> NPDPEPGSHIFT;
1340 pml4index = pdpindex >> NPML4EPGSHIFT;
1341
1342 /* First, find the pdp and check that its valid. */
1343 pml4 = &pmap->pm_pml4[pml4index];
1344 if ((*pml4 & PG_V) == 0) {
1345 /* Have to allocate a new pd, recurse */
1346 if (_pmap_allocpte(pmap, NUPDE + pdpindex,
1347 flags) == NULL) {
1348 --m->wire_count;
1349 vm_page_free(m);
1350 return (NULL);
1351 }
1352 pdp = (pdp_entry_t *)PHYS_TO_DMAP(*pml4 & PG_FRAME);
1353 pdp = &pdp[pdpindex & ((1ul << NPDPEPGSHIFT) - 1)];
1354 } else {
1355 pdp = (pdp_entry_t *)PHYS_TO_DMAP(*pml4 & PG_FRAME);
1356 pdp = &pdp[pdpindex & ((1ul << NPDPEPGSHIFT) - 1)];
1357 if ((*pdp & PG_V) == 0) {
1358 /* Have to allocate a new pd, recurse */
1359 if (_pmap_allocpte(pmap, NUPDE + pdpindex,
1360 flags) == NULL) {
1361 --m->wire_count;
1362 vm_page_free(m);
1363 return (NULL);
1364 }
1365 } else {
1366 /* Add reference to the pd page */
1367 pdpg = PHYS_TO_VM_PAGE(*pdp & PG_FRAME);
1368 pdpg->wire_count++;
1369 }
1370 }
1371 pd = (pd_entry_t *)PHYS_TO_DMAP(*pdp & PG_FRAME);
1372
1373 /* Now we know where the page directory page is */
1374 pd = &pd[ptepindex & ((1ul << NPDEPGSHIFT) - 1)];
1375 *pd = VM_PAGE_TO_PHYS(m) | PG_U | PG_RW | PG_V | PG_A | PG_M;
1376 }
1377
1378 return m;
1379 }
1380
1381 static vm_page_t
1382 pmap_allocpde(pmap_t pmap, vm_offset_t va, int flags)
1383 {
1384 vm_pindex_t pdpindex, ptepindex;
1385 pdp_entry_t *pdpe;
1386 vm_page_t pdpg;
1387
1388 KASSERT((flags & (M_NOWAIT | M_WAITOK)) == M_NOWAIT ||
1389 (flags & (M_NOWAIT | M_WAITOK)) == M_WAITOK,
1390 ("pmap_allocpde: flags is neither M_NOWAIT nor M_WAITOK"));
1391 retry:
1392 pdpe = pmap_pdpe(pmap, va);
1393 if (pdpe != NULL && (*pdpe & PG_V) != 0) {
1394 /* Add a reference to the pd page. */
1395 pdpg = PHYS_TO_VM_PAGE(*pdpe & PG_FRAME);
1396 pdpg->wire_count++;
1397 } else {
1398 /* Allocate a pd page. */
1399 ptepindex = pmap_pde_pindex(va);
1400 pdpindex = ptepindex >> NPDPEPGSHIFT;
1401 pdpg = _pmap_allocpte(pmap, NUPDE + pdpindex, flags);
1402 if (pdpg == NULL && (flags & M_WAITOK))
1403 goto retry;
1404 }
1405 return (pdpg);
1406 }
1407
1408 static vm_page_t
1409 pmap_allocpte(pmap_t pmap, vm_offset_t va, int flags)
1410 {
1411 vm_pindex_t ptepindex;
1412 pd_entry_t *pd;
1413 vm_page_t m, free;
1414
1415 KASSERT((flags & (M_NOWAIT | M_WAITOK)) == M_NOWAIT ||
1416 (flags & (M_NOWAIT | M_WAITOK)) == M_WAITOK,
1417 ("pmap_allocpte: flags is neither M_NOWAIT nor M_WAITOK"));
1418
1419 /*
1420 * Calculate pagetable page index
1421 */
1422 ptepindex = pmap_pde_pindex(va);
1423 retry:
1424 /*
1425 * Get the page directory entry
1426 */
1427 pd = pmap_pde(pmap, va);
1428
1429 /*
1430 * This supports switching from a 2MB page to a
1431 * normal 4K page.
1432 */
1433 if (pd != 0 && (*pd & (PG_PS | PG_V)) == (PG_PS | PG_V)) {
1434 *pd = 0;
1435 pd = 0;
1436 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
1437 free = NULL;
1438 pmap_unuse_pt(pmap, va, *pmap_pdpe(pmap, va), &free);
1439 pmap_invalidate_all(kernel_pmap);
1440 pmap_free_zero_pages(free);
1441 }
1442
1443 /*
1444 * If the page table page is mapped, we just increment the
1445 * hold count, and activate it.
1446 */
1447 if (pd != 0 && (*pd & PG_V) != 0) {
1448 m = PHYS_TO_VM_PAGE(*pd & PG_FRAME);
1449 m->wire_count++;
1450 } else {
1451 /*
1452 * Here if the pte page isn't mapped, or if it has been
1453 * deallocated.
1454 */
1455 m = _pmap_allocpte(pmap, ptepindex, flags);
1456 if (m == NULL && (flags & M_WAITOK))
1457 goto retry;
1458 }
1459 return (m);
1460 }
1461
1462
1463 /***************************************************
1464 * Pmap allocation/deallocation routines.
1465 ***************************************************/
1466
1467 /*
1468 * Release any resources held by the given physical map.
1469 * Called when a pmap initialized by pmap_pinit is being released.
1470 * Should only be called if the map contains no valid mappings.
1471 */
1472 void
1473 pmap_release(pmap_t pmap)
1474 {
1475 vm_page_t m;
1476
1477 KASSERT(pmap->pm_stats.resident_count == 0,
1478 ("pmap_release: pmap resident count %ld != 0",
1479 pmap->pm_stats.resident_count));
1480
1481 m = PHYS_TO_VM_PAGE(pmap->pm_pml4[PML4PML4I] & PG_FRAME);
1482
1483 pmap->pm_pml4[KPML4I] = 0; /* KVA */
1484 pmap->pm_pml4[DMPML4I] = 0; /* Direct Map */
1485 pmap->pm_pml4[PML4PML4I] = 0; /* Recursive Mapping */
1486
1487 m->wire_count--;
1488 atomic_subtract_int(&cnt.v_wire_count, 1);
1489 vm_page_free_zero(m);
1490 PMAP_LOCK_DESTROY(pmap);
1491 }
1492
1493 static int
1494 kvm_size(SYSCTL_HANDLER_ARGS)
1495 {
1496 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE;
1497
1498 return sysctl_handle_long(oidp, &ksize, 0, req);
1499 }
1500 SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD,
1501 0, 0, kvm_size, "LU", "Size of KVM");
1502
1503 static int
1504 kvm_free(SYSCTL_HANDLER_ARGS)
1505 {
1506 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end;
1507
1508 return sysctl_handle_long(oidp, &kfree, 0, req);
1509 }
1510 SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD,
1511 0, 0, kvm_free, "LU", "Amount of KVM free");
1512
1513 /*
1514 * grow the number of kernel page table entries, if needed
1515 */
1516 void
1517 pmap_growkernel(vm_offset_t addr)
1518 {
1519 vm_paddr_t paddr;
1520 vm_page_t nkpg;
1521 pd_entry_t *pde, newpdir;
1522 pdp_entry_t newpdp;
1523
1524 mtx_assert(&kernel_map->system_mtx, MA_OWNED);
1525 if (kernel_vm_end == 0) {
1526 kernel_vm_end = KERNBASE;
1527 nkpt = 0;
1528 while ((*pmap_pde(kernel_pmap, kernel_vm_end) & PG_V) != 0) {
1529 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
1530 nkpt++;
1531 if (kernel_vm_end - 1 >= kernel_map->max_offset) {
1532 kernel_vm_end = kernel_map->max_offset;
1533 break;
1534 }
1535 }
1536 }
1537 addr = roundup2(addr, PAGE_SIZE * NPTEPG);
1538 if (addr - 1 >= kernel_map->max_offset)
1539 addr = kernel_map->max_offset;
1540 while (kernel_vm_end < addr) {
1541 pde = pmap_pde(kernel_pmap, kernel_vm_end);
1542 if (pde == NULL) {
1543 /* We need a new PDP entry */
1544 nkpg = vm_page_alloc(NULL, nkpt,
1545 VM_ALLOC_NOOBJ | VM_ALLOC_SYSTEM | VM_ALLOC_WIRED);
1546 if (!nkpg)
1547 panic("pmap_growkernel: no memory to grow kernel");
1548 pmap_zero_page(nkpg);
1549 paddr = VM_PAGE_TO_PHYS(nkpg);
1550 newpdp = (pdp_entry_t)
1551 (paddr | PG_V | PG_RW | PG_A | PG_M);
1552 *pmap_pdpe(kernel_pmap, kernel_vm_end) = newpdp;
1553 continue; /* try again */
1554 }
1555 if ((*pde & PG_V) != 0) {
1556 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
1557 if (kernel_vm_end - 1 >= kernel_map->max_offset) {
1558 kernel_vm_end = kernel_map->max_offset;
1559 break;
1560 }
1561 continue;
1562 }
1563
1564 /*
1565 * This index is bogus, but out of the way
1566 */
1567 nkpg = vm_page_alloc(NULL, nkpt,
1568 VM_ALLOC_NOOBJ | VM_ALLOC_SYSTEM | VM_ALLOC_WIRED);
1569 if (!nkpg)
1570 panic("pmap_growkernel: no memory to grow kernel");
1571
1572 nkpt++;
1573
1574 pmap_zero_page(nkpg);
1575 paddr = VM_PAGE_TO_PHYS(nkpg);
1576 newpdir = (pd_entry_t) (paddr | PG_V | PG_RW | PG_A | PG_M);
1577 *pmap_pde(kernel_pmap, kernel_vm_end) = newpdir;
1578
1579 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
1580 if (kernel_vm_end - 1 >= kernel_map->max_offset) {
1581 kernel_vm_end = kernel_map->max_offset;
1582 break;
1583 }
1584 }
1585 }
1586
1587
1588 /***************************************************
1589 * page management routines.
1590 ***************************************************/
1591
1592 CTASSERT(sizeof(struct pv_chunk) == PAGE_SIZE);
1593 CTASSERT(_NPCM == 3);
1594 CTASSERT(_NPCPV == 168);
1595
1596 static __inline struct pv_chunk *
1597 pv_to_chunk(pv_entry_t pv)
1598 {
1599
1600 return (struct pv_chunk *)((uintptr_t)pv & ~(uintptr_t)PAGE_MASK);
1601 }
1602
1603 #define PV_PMAP(pv) (pv_to_chunk(pv)->pc_pmap)
1604
1605 #define PC_FREE0 0xfffffffffffffffful
1606 #define PC_FREE1 0xfffffffffffffffful
1607 #define PC_FREE2 0x000000fffffffffful
1608
1609 static uint64_t pc_freemask[_NPCM] = { PC_FREE0, PC_FREE1, PC_FREE2 };
1610
1611 SYSCTL_INT(_vm_pmap, OID_AUTO, pv_entry_count, CTLFLAG_RD, &pv_entry_count, 0,
1612 "Current number of pv entries");
1613
1614 #ifdef PV_STATS
1615 static int pc_chunk_count, pc_chunk_allocs, pc_chunk_frees, pc_chunk_tryfail;
1616
1617 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_count, CTLFLAG_RD, &pc_chunk_count, 0,
1618 "Current number of pv entry chunks");
1619 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_allocs, CTLFLAG_RD, &pc_chunk_allocs, 0,
1620 "Current number of pv entry chunks allocated");
1621 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_frees, CTLFLAG_RD, &pc_chunk_frees, 0,
1622 "Current number of pv entry chunks frees");
1623 SYSCTL_INT(_vm_pmap, OID_AUTO, pc_chunk_tryfail, CTLFLAG_RD, &pc_chunk_tryfail, 0,
1624 "Number of times tried to get a chunk page but failed.");
1625
1626 static long pv_entry_frees, pv_entry_allocs;
1627 static int pv_entry_spare;
1628
1629 SYSCTL_LONG(_vm_pmap, OID_AUTO, pv_entry_frees, CTLFLAG_RD, &pv_entry_frees, 0,
1630 "Current number of pv entry frees");
1631 SYSCTL_LONG(_vm_pmap, OID_AUTO, pv_entry_allocs, CTLFLAG_RD, &pv_entry_allocs, 0,
1632 "Current number of pv entry allocs");
1633 SYSCTL_INT(_vm_pmap, OID_AUTO, pv_entry_spare, CTLFLAG_RD, &pv_entry_spare, 0,
1634 "Current number of spare pv entries");
1635
1636 static int pmap_collect_inactive, pmap_collect_active;
1637
1638 SYSCTL_INT(_vm_pmap, OID_AUTO, pmap_collect_inactive, CTLFLAG_RD, &pmap_collect_inactive, 0,
1639 "Current number times pmap_collect called on inactive queue");
1640 SYSCTL_INT(_vm_pmap, OID_AUTO, pmap_collect_active, CTLFLAG_RD, &pmap_collect_active, 0,
1641 "Current number times pmap_collect called on active queue");
1642 #endif
1643
1644 /*
1645 * We are in a serious low memory condition. Resort to
1646 * drastic measures to free some pages so we can allocate
1647 * another pv entry chunk. This is normally called to
1648 * unmap inactive pages, and if necessary, active pages.
1649 */
1650 static void
1651 pmap_collect(pmap_t locked_pmap, struct vpgqueues *vpq)
1652 {
1653 pd_entry_t ptepde;
1654 pmap_t pmap;
1655 pt_entry_t *pte, tpte;
1656 pv_entry_t next_pv, pv;
1657 vm_offset_t va;
1658 vm_page_t m, free;
1659
1660 TAILQ_FOREACH(m, &vpq->pl, pageq) {
1661 if (m->hold_count || m->busy)
1662 continue;
1663 TAILQ_FOREACH_SAFE(pv, &m->md.pv_list, pv_list, next_pv) {
1664 va = pv->pv_va;
1665 pmap = PV_PMAP(pv);
1666 /* Avoid deadlock and lock recursion. */
1667 if (pmap > locked_pmap)
1668 PMAP_LOCK(pmap);
1669 else if (pmap != locked_pmap && !PMAP_TRYLOCK(pmap))
1670 continue;
1671 pmap->pm_stats.resident_count--;
1672 pte = pmap_pte_pde(pmap, va, &ptepde);
1673 if (pte == NULL) {
1674 panic("null pte in pmap_collect");
1675 }
1676 tpte = pte_load_clear(pte);
1677 KASSERT((tpte & PG_W) == 0,
1678 ("pmap_collect: wired pte %#lx", tpte));
1679 if (tpte & PG_A)
1680 vm_page_flag_set(m, PG_REFERENCED);
1681 if (tpte & PG_M) {
1682 KASSERT((tpte & PG_RW),
1683 ("pmap_collect: modified page not writable: va: %#lx, pte: %#lx",
1684 va, tpte));
1685 vm_page_dirty(m);
1686 }
1687 free = NULL;
1688 pmap_unuse_pt(pmap, va, ptepde, &free);
1689 pmap_invalidate_page(pmap, va);
1690 pmap_free_zero_pages(free);
1691 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
1692 if (TAILQ_EMPTY(&m->md.pv_list))
1693 vm_page_flag_clear(m, PG_WRITEABLE);
1694 m->md.pv_list_count--;
1695 free_pv_entry(pmap, pv);
1696 if (pmap != locked_pmap)
1697 PMAP_UNLOCK(pmap);
1698 }
1699 }
1700 }
1701
1702
1703 /*
1704 * free the pv_entry back to the free list
1705 */
1706 static void
1707 free_pv_entry(pmap_t pmap, pv_entry_t pv)
1708 {
1709 vm_page_t m;
1710 struct pv_chunk *pc;
1711 int idx, field, bit;
1712
1713 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1714 PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1715 PV_STAT(pv_entry_frees++);
1716 PV_STAT(pv_entry_spare++);
1717 pv_entry_count--;
1718 pc = pv_to_chunk(pv);
1719 idx = pv - &pc->pc_pventry[0];
1720 field = idx / 64;
1721 bit = idx % 64;
1722 pc->pc_map[field] |= 1ul << bit;
1723 /* move to head of list */
1724 TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
1725 TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc, pc_list);
1726 if (pc->pc_map[0] != PC_FREE0 || pc->pc_map[1] != PC_FREE1 ||
1727 pc->pc_map[2] != PC_FREE2)
1728 return;
1729 PV_STAT(pv_entry_spare -= _NPCPV);
1730 PV_STAT(pc_chunk_count--);
1731 PV_STAT(pc_chunk_frees++);
1732 /* entire chunk is free, return it */
1733 TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
1734 m = PHYS_TO_VM_PAGE(DMAP_TO_PHYS((vm_offset_t)pc));
1735 dump_drop_page(m->phys_addr);
1736 vm_page_free(m);
1737 }
1738
1739 /*
1740 * get a new pv_entry, allocating a block from the system
1741 * when needed.
1742 */
1743 static pv_entry_t
1744 get_pv_entry(pmap_t pmap, int try)
1745 {
1746 static const struct timeval printinterval = { 60, 0 };
1747 static struct timeval lastprint;
1748 static vm_pindex_t colour;
1749 int bit, field;
1750 pv_entry_t pv;
1751 struct pv_chunk *pc;
1752 vm_page_t m;
1753
1754 PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1755 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1756 PV_STAT(pv_entry_allocs++);
1757 pv_entry_count++;
1758 if (pv_entry_count > pv_entry_high_water)
1759 if (ratecheck(&lastprint, &printinterval))
1760 printf("Approaching the limit on PV entries, consider "
1761 "increasing either the vm.pmap.shpgperproc or the "
1762 "vm.pmap.pv_entry_max sysctl.\n");
1763 pc = TAILQ_FIRST(&pmap->pm_pvchunk);
1764 if (pc != NULL) {
1765 for (field = 0; field < _NPCM; field++) {
1766 if (pc->pc_map[field]) {
1767 bit = bsfq(pc->pc_map[field]);
1768 break;
1769 }
1770 }
1771 if (field < _NPCM) {
1772 pv = &pc->pc_pventry[field * 64 + bit];
1773 pc->pc_map[field] &= ~(1ul << bit);
1774 /* If this was the last item, move it to tail */
1775 if (pc->pc_map[0] == 0 && pc->pc_map[1] == 0 &&
1776 pc->pc_map[2] == 0) {
1777 TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
1778 TAILQ_INSERT_TAIL(&pmap->pm_pvchunk, pc, pc_list);
1779 }
1780 PV_STAT(pv_entry_spare--);
1781 return (pv);
1782 }
1783 }
1784 /* No free items, allocate another chunk */
1785 m = vm_page_alloc(NULL, colour, VM_ALLOC_NORMAL | VM_ALLOC_NOOBJ);
1786 if (m == NULL) {
1787 if (try) {
1788 pv_entry_count--;
1789 PV_STAT(pc_chunk_tryfail++);
1790 return (NULL);
1791 }
1792 /*
1793 * Reclaim pv entries: At first, destroy mappings to inactive
1794 * pages. After that, if a pv chunk entry is still needed,
1795 * destroy mappings to active pages.
1796 */
1797 PV_STAT(pmap_collect_inactive++);
1798 pmap_collect(pmap, &vm_page_queues[PQ_INACTIVE]);
1799 m = vm_page_alloc(NULL, colour,
1800 VM_ALLOC_NORMAL | VM_ALLOC_NOOBJ);
1801 if (m == NULL) {
1802 PV_STAT(pmap_collect_active++);
1803 pmap_collect(pmap, &vm_page_queues[PQ_ACTIVE]);
1804 m = vm_page_alloc(NULL, colour,
1805 VM_ALLOC_SYSTEM | VM_ALLOC_NOOBJ);
1806 if (m == NULL)
1807 panic("get_pv_entry: increase vm.pmap.shpgperproc");
1808 }
1809 }
1810 PV_STAT(pc_chunk_count++);
1811 PV_STAT(pc_chunk_allocs++);
1812 colour++;
1813 dump_add_page(m->phys_addr);
1814 pc = (void *)PHYS_TO_DMAP(m->phys_addr);
1815 pc->pc_pmap = pmap;
1816 pc->pc_map[0] = PC_FREE0 & ~1ul; /* preallocated bit 0 */
1817 pc->pc_map[1] = PC_FREE1;
1818 pc->pc_map[2] = PC_FREE2;
1819 pv = &pc->pc_pventry[0];
1820 TAILQ_INSERT_HEAD(&pmap->pm_pvchunk, pc, pc_list);
1821 PV_STAT(pv_entry_spare += _NPCPV - 1);
1822 return (pv);
1823 }
1824
1825 static void
1826 pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va)
1827 {
1828 pv_entry_t pv;
1829
1830 PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1831 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1832 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
1833 if (pmap == PV_PMAP(pv) && va == pv->pv_va)
1834 break;
1835 }
1836 KASSERT(pv != NULL, ("pmap_remove_entry: pv not found"));
1837 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
1838 m->md.pv_list_count--;
1839 if (TAILQ_EMPTY(&m->md.pv_list))
1840 vm_page_flag_clear(m, PG_WRITEABLE);
1841 free_pv_entry(pmap, pv);
1842 }
1843
1844 /*
1845 * Create a pv entry for page at pa for
1846 * (pmap, va).
1847 */
1848 static void
1849 pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t m)
1850 {
1851 pv_entry_t pv;
1852
1853 PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1854 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1855 pv = get_pv_entry(pmap, FALSE);
1856 pv->pv_va = va;
1857 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
1858 m->md.pv_list_count++;
1859 }
1860
1861 /*
1862 * Conditionally create a pv entry.
1863 */
1864 static boolean_t
1865 pmap_try_insert_pv_entry(pmap_t pmap, vm_offset_t va, vm_page_t m)
1866 {
1867 pv_entry_t pv;
1868
1869 PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1870 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1871 if (pv_entry_count < pv_entry_high_water &&
1872 (pv = get_pv_entry(pmap, TRUE)) != NULL) {
1873 pv->pv_va = va;
1874 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
1875 m->md.pv_list_count++;
1876 return (TRUE);
1877 } else
1878 return (FALSE);
1879 }
1880
1881 /*
1882 * pmap_remove_pte: do the things to unmap a page in a process
1883 */
1884 static int
1885 pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va,
1886 pd_entry_t ptepde, vm_page_t *free)
1887 {
1888 pt_entry_t oldpte;
1889 vm_page_t m;
1890
1891 PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1892 oldpte = pte_load_clear(ptq);
1893 if (oldpte & PG_W)
1894 pmap->pm_stats.wired_count -= 1;
1895 /*
1896 * Machines that don't support invlpg, also don't support
1897 * PG_G.
1898 */
1899 if (oldpte & PG_G)
1900 pmap_invalidate_page(kernel_pmap, va);
1901 pmap->pm_stats.resident_count -= 1;
1902 if (oldpte & PG_MANAGED) {
1903 m = PHYS_TO_VM_PAGE(oldpte & PG_FRAME);
1904 if (oldpte & PG_M) {
1905 KASSERT((oldpte & PG_RW),
1906 ("pmap_remove_pte: modified page not writable: va: %#lx, pte: %#lx",
1907 va, oldpte));
1908 vm_page_dirty(m);
1909 }
1910 if (oldpte & PG_A)
1911 vm_page_flag_set(m, PG_REFERENCED);
1912 pmap_remove_entry(pmap, m, va);
1913 }
1914 return (pmap_unuse_pt(pmap, va, ptepde, free));
1915 }
1916
1917 /*
1918 * Remove a single page from a process address space
1919 */
1920 static void
1921 pmap_remove_page(pmap_t pmap, vm_offset_t va, pd_entry_t *pde, vm_page_t *free)
1922 {
1923 pt_entry_t *pte;
1924
1925 PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1926 if ((*pde & PG_V) == 0)
1927 return;
1928 pte = pmap_pde_to_pte(pde, va);
1929 if ((*pte & PG_V) == 0)
1930 return;
1931 pmap_remove_pte(pmap, pte, va, *pde, free);
1932 pmap_invalidate_page(pmap, va);
1933 }
1934
1935 /*
1936 * Remove the given range of addresses from the specified map.
1937 *
1938 * It is assumed that the start and end are properly
1939 * rounded to the page size.
1940 */
1941 void
1942 pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
1943 {
1944 vm_offset_t va_next;
1945 pml4_entry_t *pml4e;
1946 pdp_entry_t *pdpe;
1947 pd_entry_t ptpaddr, *pde;
1948 pt_entry_t *pte;
1949 vm_page_t free = NULL;
1950 int anyvalid;
1951
1952 /*
1953 * Perform an unsynchronized read. This is, however, safe.
1954 */
1955 if (pmap->pm_stats.resident_count == 0)
1956 return;
1957
1958 anyvalid = 0;
1959
1960 vm_page_lock_queues();
1961 PMAP_LOCK(pmap);
1962
1963 /*
1964 * special handling of removing one page. a very
1965 * common operation and easy to short circuit some
1966 * code.
1967 */
1968 if (sva + PAGE_SIZE == eva) {
1969 pde = pmap_pde(pmap, sva);
1970 if (pde && (*pde & PG_PS) == 0) {
1971 pmap_remove_page(pmap, sva, pde, &free);
1972 goto out;
1973 }
1974 }
1975
1976 for (; sva < eva; sva = va_next) {
1977
1978 if (pmap->pm_stats.resident_count == 0)
1979 break;
1980
1981 pml4e = pmap_pml4e(pmap, sva);
1982 if ((*pml4e & PG_V) == 0) {
1983 va_next = (sva + NBPML4) & ~PML4MASK;
1984 continue;
1985 }
1986
1987 pdpe = pmap_pml4e_to_pdpe(pml4e, sva);
1988 if ((*pdpe & PG_V) == 0) {
1989 va_next = (sva + NBPDP) & ~PDPMASK;
1990 continue;
1991 }
1992
1993 /*
1994 * Calculate index for next page table.
1995 */
1996 va_next = (sva + NBPDR) & ~PDRMASK;
1997
1998 pde = pmap_pdpe_to_pde(pdpe, sva);
1999 ptpaddr = *pde;
2000
2001 /*
2002 * Weed out invalid mappings.
2003 */
2004 if (ptpaddr == 0)
2005 continue;
2006
2007 /*
2008 * Check for large page.
2009 */
2010 if ((ptpaddr & PG_PS) != 0) {
2011 *pde = 0;
2012 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
2013 pmap_unuse_pt(pmap, sva, *pdpe, &free);
2014 anyvalid = 1;
2015 continue;
2016 }
2017
2018 /*
2019 * Limit our scan to either the end of the va represented
2020 * by the current page table page, or to the end of the
2021 * range being removed.
2022 */
2023 if (va_next > eva)
2024 va_next = eva;
2025
2026 for (pte = pmap_pde_to_pte(pde, sva); sva != va_next; pte++,
2027 sva += PAGE_SIZE) {
2028 if (*pte == 0)
2029 continue;
2030
2031 /*
2032 * The TLB entry for a PG_G mapping is invalidated
2033 * by pmap_remove_pte().
2034 */
2035 if ((*pte & PG_G) == 0)
2036 anyvalid = 1;
2037 if (pmap_remove_pte(pmap, pte, sva, ptpaddr, &free))
2038 break;
2039 }
2040 }
2041 out:
2042 if (anyvalid)
2043 pmap_invalidate_all(pmap);
2044 vm_page_unlock_queues();
2045 PMAP_UNLOCK(pmap);
2046 pmap_free_zero_pages(free);
2047 }
2048
2049 /*
2050 * Routine: pmap_remove_all
2051 * Function:
2052 * Removes this physical page from
2053 * all physical maps in which it resides.
2054 * Reflects back modify bits to the pager.
2055 *
2056 * Notes:
2057 * Original versions of this routine were very
2058 * inefficient because they iteratively called
2059 * pmap_remove (slow...)
2060 */
2061
2062 void
2063 pmap_remove_all(vm_page_t m)
2064 {
2065 pv_entry_t pv;
2066 pmap_t pmap;
2067 pt_entry_t *pte, tpte;
2068 pd_entry_t ptepde;
2069 vm_page_t free;
2070
2071 #if defined(PMAP_DIAGNOSTIC)
2072 /*
2073 * XXX This makes pmap_remove_all() illegal for non-managed pages!
2074 */
2075 if (m->flags & PG_FICTITIOUS) {
2076 panic("pmap_remove_all: illegal for unmanaged page, va: 0x%lx",
2077 VM_PAGE_TO_PHYS(m));
2078 }
2079 #endif
2080 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
2081 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
2082 pmap = PV_PMAP(pv);
2083 PMAP_LOCK(pmap);
2084 pmap->pm_stats.resident_count--;
2085 pte = pmap_pte_pde(pmap, pv->pv_va, &ptepde);
2086 if (pte == NULL) {
2087 panic("null pte in pmap_remove_all");
2088 }
2089 tpte = pte_load_clear(pte);
2090 if (tpte & PG_W)
2091 pmap->pm_stats.wired_count--;
2092 if (tpte & PG_A)
2093 vm_page_flag_set(m, PG_REFERENCED);
2094
2095 /*
2096 * Update the vm_page_t clean and reference bits.
2097 */
2098 if (tpte & PG_M) {
2099 KASSERT((tpte & PG_RW),
2100 ("pmap_remove_all: modified page not writable: va: %#lx, pte: %#lx",
2101 pv->pv_va, tpte));
2102 vm_page_dirty(m);
2103 }
2104 free = NULL;
2105 pmap_unuse_pt(pmap, pv->pv_va, ptepde, &free);
2106 pmap_invalidate_page(pmap, pv->pv_va);
2107 pmap_free_zero_pages(free);
2108 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
2109 m->md.pv_list_count--;
2110 free_pv_entry(pmap, pv);
2111 PMAP_UNLOCK(pmap);
2112 }
2113 vm_page_flag_clear(m, PG_WRITEABLE);
2114 }
2115
2116 /*
2117 * Set the physical protection on the
2118 * specified range of this map as requested.
2119 */
2120 void
2121 pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
2122 {
2123 vm_offset_t va_next;
2124 pml4_entry_t *pml4e;
2125 pdp_entry_t *pdpe;
2126 pd_entry_t ptpaddr, *pde;
2127 pt_entry_t *pte;
2128 int anychanged;
2129
2130 if ((prot & VM_PROT_READ) == VM_PROT_NONE) {
2131 pmap_remove(pmap, sva, eva);
2132 return;
2133 }
2134
2135 if ((prot & (VM_PROT_WRITE|VM_PROT_EXECUTE)) ==
2136 (VM_PROT_WRITE|VM_PROT_EXECUTE))
2137 return;
2138
2139 anychanged = 0;
2140
2141 vm_page_lock_queues();
2142 PMAP_LOCK(pmap);
2143 for (; sva < eva; sva = va_next) {
2144
2145 pml4e = pmap_pml4e(pmap, sva);
2146 if ((*pml4e & PG_V) == 0) {
2147 va_next = (sva + NBPML4) & ~PML4MASK;
2148 continue;
2149 }
2150
2151 pdpe = pmap_pml4e_to_pdpe(pml4e, sva);
2152 if ((*pdpe & PG_V) == 0) {
2153 va_next = (sva + NBPDP) & ~PDPMASK;
2154 continue;
2155 }
2156
2157 va_next = (sva + NBPDR) & ~PDRMASK;
2158
2159 pde = pmap_pdpe_to_pde(pdpe, sva);
2160 ptpaddr = *pde;
2161
2162 /*
2163 * Weed out invalid mappings.
2164 */
2165 if (ptpaddr == 0)
2166 continue;
2167
2168 /*
2169 * Check for large page.
2170 */
2171 if ((ptpaddr & PG_PS) != 0) {
2172 if ((prot & VM_PROT_WRITE) == 0)
2173 *pde &= ~(PG_M|PG_RW);
2174 if ((prot & VM_PROT_EXECUTE) == 0)
2175 *pde |= pg_nx;
2176 anychanged = 1;
2177 continue;
2178 }
2179
2180 if (va_next > eva)
2181 va_next = eva;
2182
2183 for (pte = pmap_pde_to_pte(pde, sva); sva != va_next; pte++,
2184 sva += PAGE_SIZE) {
2185 pt_entry_t obits, pbits;
2186 vm_page_t m;
2187
2188 retry:
2189 obits = pbits = *pte;
2190 if ((pbits & PG_V) == 0)
2191 continue;
2192 if (pbits & PG_MANAGED) {
2193 m = NULL;
2194 if (pbits & PG_A) {
2195 m = PHYS_TO_VM_PAGE(pbits & PG_FRAME);
2196 vm_page_flag_set(m, PG_REFERENCED);
2197 pbits &= ~PG_A;
2198 }
2199 if ((pbits & PG_M) != 0) {
2200 if (m == NULL)
2201 m = PHYS_TO_VM_PAGE(pbits &
2202 PG_FRAME);
2203 vm_page_dirty(m);
2204 }
2205 }
2206
2207 if ((prot & VM_PROT_WRITE) == 0)
2208 pbits &= ~(PG_RW | PG_M);
2209 if ((prot & VM_PROT_EXECUTE) == 0)
2210 pbits |= pg_nx;
2211
2212 if (pbits != obits) {
2213 if (!atomic_cmpset_long(pte, obits, pbits))
2214 goto retry;
2215 if (obits & PG_G)
2216 pmap_invalidate_page(pmap, sva);
2217 else
2218 anychanged = 1;
2219 }
2220 }
2221 }
2222 if (anychanged)
2223 pmap_invalidate_all(pmap);
2224 vm_page_unlock_queues();
2225 PMAP_UNLOCK(pmap);
2226 }
2227
2228 /*
2229 * Insert the given physical page (p) at
2230 * the specified virtual address (v) in the
2231 * target physical map with the protection requested.
2232 *
2233 * If specified, the page will be wired down, meaning
2234 * that the related pte can not be reclaimed.
2235 *
2236 * NB: This is the only routine which MAY NOT lazy-evaluate
2237 * or lose information. That is, this routine must actually
2238 * insert this page into the given map NOW.
2239 */
2240 void
2241 pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
2242 boolean_t wired)
2243 {
2244 vm_paddr_t pa;
2245 pd_entry_t *pde;
2246 pt_entry_t *pte;
2247 vm_paddr_t opa;
2248 pt_entry_t origpte, newpte;
2249 vm_page_t mpte, om;
2250 boolean_t invlva;
2251
2252 va = trunc_page(va);
2253 #ifdef PMAP_DIAGNOSTIC
2254 if (va > VM_MAX_KERNEL_ADDRESS)
2255 panic("pmap_enter: toobig");
2256 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS))
2257 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%lx)", va);
2258 #endif
2259
2260 mpte = NULL;
2261
2262 vm_page_lock_queues();
2263 PMAP_LOCK(pmap);
2264
2265 /*
2266 * In the case that a page table page is not
2267 * resident, we are creating it here.
2268 */
2269 if (va < VM_MAXUSER_ADDRESS) {
2270 mpte = pmap_allocpte(pmap, va, M_WAITOK);
2271 }
2272 #if 0 && defined(PMAP_DIAGNOSTIC)
2273 else {
2274 pd_entry_t *pdeaddr = pmap_pde(pmap, va);
2275 origpte = *pdeaddr;
2276 if ((origpte & PG_V) == 0) {
2277 panic("pmap_enter: invalid kernel page table page, pde=%p, va=%p\n",
2278 origpte, va);
2279 }
2280 }
2281 #endif
2282
2283 pde = pmap_pde(pmap, va);
2284 if (pde != NULL) {
2285 if ((*pde & PG_PS) != 0)
2286 panic("pmap_enter: attempted pmap_enter on 2MB page");
2287 pte = pmap_pde_to_pte(pde, va);
2288 } else
2289 pte = NULL;
2290
2291 /*
2292 * Page Directory table entry not valid, we need a new PT page
2293 */
2294 if (pte == NULL)
2295 panic("pmap_enter: invalid page directory va=%#lx\n", va);
2296
2297 pa = VM_PAGE_TO_PHYS(m);
2298 om = NULL;
2299 origpte = *pte;
2300 opa = origpte & PG_FRAME;
2301
2302 /*
2303 * Mapping has not changed, must be protection or wiring change.
2304 */
2305 if (origpte && (opa == pa)) {
2306 /*
2307 * Wiring change, just update stats. We don't worry about
2308 * wiring PT pages as they remain resident as long as there
2309 * are valid mappings in them. Hence, if a user page is wired,
2310 * the PT page will be also.
2311 */
2312 if (wired && ((origpte & PG_W) == 0))
2313 pmap->pm_stats.wired_count++;
2314 else if (!wired && (origpte & PG_W))
2315 pmap->pm_stats.wired_count--;
2316
2317 /*
2318 * Remove extra pte reference
2319 */
2320 if (mpte)
2321 mpte->wire_count--;
2322
2323 /*
2324 * We might be turning off write access to the page,
2325 * so we go ahead and sense modify status.
2326 */
2327 if (origpte & PG_MANAGED) {
2328 om = m;
2329 pa |= PG_MANAGED;
2330 }
2331 goto validate;
2332 }
2333 /*
2334 * Mapping has changed, invalidate old range and fall through to
2335 * handle validating new mapping.
2336 */
2337 if (opa) {
2338 if (origpte & PG_W)
2339 pmap->pm_stats.wired_count--;
2340 if (origpte & PG_MANAGED) {
2341 om = PHYS_TO_VM_PAGE(opa);
2342 pmap_remove_entry(pmap, om, va);
2343 }
2344 if (mpte != NULL) {
2345 mpte->wire_count--;
2346 KASSERT(mpte->wire_count > 0,
2347 ("pmap_enter: missing reference to page table page,"
2348 " va: 0x%lx", va));
2349 }
2350 } else
2351 pmap->pm_stats.resident_count++;
2352
2353 /*
2354 * Enter on the PV list if part of our managed memory.
2355 */
2356 if ((m->flags & (PG_FICTITIOUS | PG_UNMANAGED)) == 0) {
2357 KASSERT(va < kmi.clean_sva || va >= kmi.clean_eva,
2358 ("pmap_enter: managed mapping within the clean submap"));
2359 pmap_insert_entry(pmap, va, m);
2360 pa |= PG_MANAGED;
2361 }
2362
2363 /*
2364 * Increment counters
2365 */
2366 if (wired)
2367 pmap->pm_stats.wired_count++;
2368
2369 validate:
2370 /*
2371 * Now validate mapping with desired protection/wiring.
2372 */
2373 newpte = (pt_entry_t)(pa | PG_V);
2374 if ((prot & VM_PROT_WRITE) != 0) {
2375 newpte |= PG_RW;
2376 vm_page_flag_set(m, PG_WRITEABLE);
2377 }
2378 if ((prot & VM_PROT_EXECUTE) == 0)
2379 newpte |= pg_nx;
2380 if (wired)
2381 newpte |= PG_W;
2382 if (va < VM_MAXUSER_ADDRESS)
2383 newpte |= PG_U;
2384 if (pmap == kernel_pmap)
2385 newpte |= PG_G;
2386
2387 /*
2388 * if the mapping or permission bits are different, we need
2389 * to update the pte.
2390 */
2391 if ((origpte & ~(PG_M|PG_A)) != newpte) {
2392 if (origpte & PG_V) {
2393 invlva = FALSE;
2394 origpte = pte_load_store(pte, newpte | PG_A);
2395 if (origpte & PG_A) {
2396 if (origpte & PG_MANAGED)
2397 vm_page_flag_set(om, PG_REFERENCED);
2398 if (opa != VM_PAGE_TO_PHYS(m) || ((origpte &
2399 PG_NX) == 0 && (newpte & PG_NX)))
2400 invlva = TRUE;
2401 }
2402 if (origpte & PG_M) {
2403 KASSERT((origpte & PG_RW),
2404 ("pmap_enter: modified page not writable: va: %#lx, pte: %#lx",
2405 va, origpte));
2406 if ((origpte & PG_MANAGED) != 0)
2407 vm_page_dirty(om);
2408 if ((newpte & PG_RW) == 0)
2409 invlva = TRUE;
2410 }
2411 if (invlva)
2412 pmap_invalidate_page(pmap, va);
2413 } else
2414 pte_store(pte, newpte | PG_A);
2415 }
2416 vm_page_unlock_queues();
2417 PMAP_UNLOCK(pmap);
2418 }
2419
2420 /*
2421 * Maps a sequence of resident pages belonging to the same object.
2422 * The sequence begins with the given page m_start. This page is
2423 * mapped at the given virtual address start. Each subsequent page is
2424 * mapped at a virtual address that is offset from start by the same
2425 * amount as the page is offset from m_start within the object. The
2426 * last page in the sequence is the page with the largest offset from
2427 * m_start that can be mapped at a virtual address less than the given
2428 * virtual address end. Not every virtual page between start and end
2429 * is mapped; only those for which a resident page exists with the
2430 * corresponding offset from m_start are mapped.
2431 */
2432 void
2433 pmap_enter_object(pmap_t pmap, vm_offset_t start, vm_offset_t end,
2434 vm_page_t m_start, vm_prot_t prot)
2435 {
2436 vm_page_t m, mpte;
2437 vm_pindex_t diff, psize;
2438
2439 VM_OBJECT_LOCK_ASSERT(m_start->object, MA_OWNED);
2440 psize = atop(end - start);
2441 mpte = NULL;
2442 m = m_start;
2443 PMAP_LOCK(pmap);
2444 while (m != NULL && (diff = m->pindex - m_start->pindex) < psize) {
2445 mpte = pmap_enter_quick_locked(pmap, start + ptoa(diff), m,
2446 prot, mpte);
2447 m = TAILQ_NEXT(m, listq);
2448 }
2449 PMAP_UNLOCK(pmap);
2450 }
2451
2452 /*
2453 * this code makes some *MAJOR* assumptions:
2454 * 1. Current pmap & pmap exists.
2455 * 2. Not wired.
2456 * 3. Read access.
2457 * 4. No page table pages.
2458 * but is *MUCH* faster than pmap_enter...
2459 */
2460
2461 void
2462 pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot)
2463 {
2464
2465 PMAP_LOCK(pmap);
2466 (void) pmap_enter_quick_locked(pmap, va, m, prot, NULL);
2467 PMAP_UNLOCK(pmap);
2468 }
2469
2470 static vm_page_t
2471 pmap_enter_quick_locked(pmap_t pmap, vm_offset_t va, vm_page_t m,
2472 vm_prot_t prot, vm_page_t mpte)
2473 {
2474 vm_page_t free;
2475 pt_entry_t *pte;
2476 vm_paddr_t pa;
2477
2478 KASSERT(va < kmi.clean_sva || va >= kmi.clean_eva ||
2479 (m->flags & (PG_FICTITIOUS | PG_UNMANAGED)) != 0,
2480 ("pmap_enter_quick_locked: managed mapping within the clean submap"));
2481 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
2482 PMAP_LOCK_ASSERT(pmap, MA_OWNED);
2483
2484 /*
2485 * In the case that a page table page is not
2486 * resident, we are creating it here.
2487 */
2488 if (va < VM_MAXUSER_ADDRESS) {
2489 vm_pindex_t ptepindex;
2490 pd_entry_t *ptepa;
2491
2492 /*
2493 * Calculate pagetable page index
2494 */
2495 ptepindex = pmap_pde_pindex(va);
2496 if (mpte && (mpte->pindex == ptepindex)) {
2497 mpte->wire_count++;
2498 } else {
2499 /*
2500 * Get the page directory entry
2501 */
2502 ptepa = pmap_pde(pmap, va);
2503
2504 /*
2505 * If the page table page is mapped, we just increment
2506 * the hold count, and activate it.
2507 */
2508 if (ptepa && (*ptepa & PG_V) != 0) {
2509 if (*ptepa & PG_PS)
2510 panic("pmap_enter_quick: unexpected mapping into 2MB page");
2511 mpte = PHYS_TO_VM_PAGE(*ptepa & PG_FRAME);
2512 mpte->wire_count++;
2513 } else {
2514 mpte = _pmap_allocpte(pmap, ptepindex,
2515 M_NOWAIT);
2516 if (mpte == NULL)
2517 return (mpte);
2518 }
2519 }
2520 } else {
2521 mpte = NULL;
2522 }
2523
2524 /*
2525 * This call to vtopte makes the assumption that we are
2526 * entering the page into the current pmap. In order to support
2527 * quick entry into any pmap, one would likely use pmap_pte.
2528 * But that isn't as quick as vtopte.
2529 */
2530 pte = vtopte(va);
2531 if (*pte) {
2532 if (mpte != NULL) {
2533 mpte->wire_count--;
2534 mpte = NULL;
2535 }
2536 return (mpte);
2537 }
2538
2539 /*
2540 * Enter on the PV list if part of our managed memory.
2541 */
2542 if ((m->flags & (PG_FICTITIOUS | PG_UNMANAGED)) == 0 &&
2543 !pmap_try_insert_pv_entry(pmap, va, m)) {
2544 if (mpte != NULL) {
2545 free = NULL;
2546 if (pmap_unwire_pte_hold(pmap, va, mpte, &free)) {
2547 pmap_invalidate_page(pmap, va);
2548 pmap_free_zero_pages(free);
2549 }
2550 mpte = NULL;
2551 }
2552 return (mpte);
2553 }
2554
2555 /*
2556 * Increment counters
2557 */
2558 pmap->pm_stats.resident_count++;
2559
2560 pa = VM_PAGE_TO_PHYS(m);
2561 if ((prot & VM_PROT_EXECUTE) == 0)
2562 pa |= pg_nx;
2563
2564 /*
2565 * Now validate mapping with RO protection
2566 */
2567 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED))
2568 pte_store(pte, pa | PG_V | PG_U);
2569 else
2570 pte_store(pte, pa | PG_V | PG_U | PG_MANAGED);
2571 return mpte;
2572 }
2573
2574 /*
2575 * Make a temporary mapping for a physical address. This is only intended
2576 * to be used for panic dumps.
2577 */
2578 void *
2579 pmap_kenter_temporary(vm_paddr_t pa, int i)
2580 {
2581 vm_offset_t va;
2582
2583 va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE);
2584 pmap_kenter(va, pa);
2585 invlpg(va);
2586 return ((void *)crashdumpmap);
2587 }
2588
2589 /*
2590 * This code maps large physical mmap regions into the
2591 * processor address space. Note that some shortcuts
2592 * are taken, but the code works.
2593 */
2594 void
2595 pmap_object_init_pt(pmap_t pmap, vm_offset_t addr,
2596 vm_object_t object, vm_pindex_t pindex,
2597 vm_size_t size)
2598 {
2599 vm_offset_t va;
2600 vm_page_t p, pdpg;
2601
2602 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED);
2603 KASSERT(object->type == OBJT_DEVICE,
2604 ("pmap_object_init_pt: non-device object"));
2605 if (((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) {
2606 vm_page_t m[1];
2607 pd_entry_t ptepa, *pde;
2608
2609 PMAP_LOCK(pmap);
2610 pde = pmap_pde(pmap, addr);
2611 if (pde != 0 && (*pde & PG_V) != 0)
2612 goto out;
2613 PMAP_UNLOCK(pmap);
2614 retry:
2615 p = vm_page_lookup(object, pindex);
2616 if (p != NULL) {
2617 if (vm_page_sleep_if_busy(p, FALSE, "init4p"))
2618 goto retry;
2619 } else {
2620 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL);
2621 if (p == NULL)
2622 return;
2623 m[0] = p;
2624
2625 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) {
2626 vm_page_lock_queues();
2627 vm_page_free(p);
2628 vm_page_unlock_queues();
2629 return;
2630 }
2631
2632 p = vm_page_lookup(object, pindex);
2633 vm_page_lock_queues();
2634 vm_page_wakeup(p);
2635 vm_page_unlock_queues();
2636 }
2637
2638 ptepa = VM_PAGE_TO_PHYS(p);
2639 if (ptepa & (NBPDR - 1))
2640 return;
2641
2642 p->valid = VM_PAGE_BITS_ALL;
2643
2644 PMAP_LOCK(pmap);
2645 for (va = addr; va < addr + size; va += NBPDR) {
2646 while ((pdpg =
2647 pmap_allocpde(pmap, va, M_NOWAIT)) == NULL) {
2648 PMAP_UNLOCK(pmap);
2649 vm_page_lock_queues();
2650 vm_page_busy(p);
2651 vm_page_unlock_queues();
2652 VM_OBJECT_UNLOCK(object);
2653 VM_WAIT;
2654 VM_OBJECT_LOCK(object);
2655 vm_page_lock_queues();
2656 vm_page_wakeup(p);
2657 vm_page_unlock_queues();
2658 PMAP_LOCK(pmap);
2659 }
2660 pde = (pd_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(pdpg));
2661 pde = &pde[pmap_pde_index(va)];
2662 if ((*pde & PG_V) == 0) {
2663 pde_store(pde, ptepa | PG_PS | PG_M | PG_A |
2664 PG_U | PG_RW | PG_V);
2665 pmap->pm_stats.resident_count +=
2666 NBPDR / PAGE_SIZE;
2667 } else {
2668 pdpg->wire_count--;
2669 KASSERT(pdpg->wire_count > 0,
2670 ("pmap_object_init_pt: missing reference "
2671 "to page directory page, va: 0x%lx", va));
2672 }
2673 ptepa += NBPDR;
2674 }
2675 pmap_invalidate_all(pmap);
2676 out:
2677 PMAP_UNLOCK(pmap);
2678 }
2679 }
2680
2681 /*
2682 * Routine: pmap_change_wiring
2683 * Function: Change the wiring attribute for a map/virtual-address
2684 * pair.
2685 * In/out conditions:
2686 * The mapping must already exist in the pmap.
2687 */
2688 void
2689 pmap_change_wiring(pmap_t pmap, vm_offset_t va, boolean_t wired)
2690 {
2691 pt_entry_t *pte;
2692
2693 /*
2694 * Wiring is not a hardware characteristic so there is no need to
2695 * invalidate TLB.
2696 */
2697 PMAP_LOCK(pmap);
2698 pte = pmap_pte(pmap, va);
2699 if (wired && (*pte & PG_W) == 0) {
2700 pmap->pm_stats.wired_count++;
2701 atomic_set_long(pte, PG_W);
2702 } else if (!wired && (*pte & PG_W) != 0) {
2703 pmap->pm_stats.wired_count--;
2704 atomic_clear_long(pte, PG_W);
2705 }
2706 PMAP_UNLOCK(pmap);
2707 }
2708
2709
2710
2711 /*
2712 * Copy the range specified by src_addr/len
2713 * from the source map to the range dst_addr/len
2714 * in the destination map.
2715 *
2716 * This routine is only advisory and need not do anything.
2717 */
2718
2719 void
2720 pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len,
2721 vm_offset_t src_addr)
2722 {
2723 vm_page_t free;
2724 vm_offset_t addr;
2725 vm_offset_t end_addr = src_addr + len;
2726 vm_offset_t va_next;
2727
2728 if (dst_addr != src_addr)
2729 return;
2730
2731 if (!pmap_is_current(src_pmap))
2732 return;
2733
2734 vm_page_lock_queues();
2735 if (dst_pmap < src_pmap) {
2736 PMAP_LOCK(dst_pmap);
2737 PMAP_LOCK(src_pmap);
2738 } else {
2739 PMAP_LOCK(src_pmap);
2740 PMAP_LOCK(dst_pmap);
2741 }
2742 for (addr = src_addr; addr < end_addr; addr = va_next) {
2743 pt_entry_t *src_pte, *dst_pte;
2744 vm_page_t dstmpde, dstmpte, srcmpte;
2745 pml4_entry_t *pml4e;
2746 pdp_entry_t *pdpe;
2747 pd_entry_t srcptepaddr, *pde;
2748
2749 if (addr >= UPT_MIN_ADDRESS)
2750 panic("pmap_copy: invalid to pmap_copy page tables");
2751
2752 pml4e = pmap_pml4e(src_pmap, addr);
2753 if ((*pml4e & PG_V) == 0) {
2754 va_next = (addr + NBPML4) & ~PML4MASK;
2755 continue;
2756 }
2757
2758 pdpe = pmap_pml4e_to_pdpe(pml4e, addr);
2759 if ((*pdpe & PG_V) == 0) {
2760 va_next = (addr + NBPDP) & ~PDPMASK;
2761 continue;
2762 }
2763
2764 va_next = (addr + NBPDR) & ~PDRMASK;
2765
2766 pde = pmap_pdpe_to_pde(pdpe, addr);
2767 srcptepaddr = *pde;
2768 if (srcptepaddr == 0)
2769 continue;
2770
2771 if (srcptepaddr & PG_PS) {
2772 dstmpde = pmap_allocpde(dst_pmap, addr, M_NOWAIT);
2773 if (dstmpde == NULL)
2774 break;
2775 pde = (pd_entry_t *)
2776 PHYS_TO_DMAP(VM_PAGE_TO_PHYS(dstmpde));
2777 pde = &pde[pmap_pde_index(addr)];
2778 if (*pde == 0) {
2779 *pde = srcptepaddr & ~PG_W;
2780 dst_pmap->pm_stats.resident_count +=
2781 NBPDR / PAGE_SIZE;
2782 } else
2783 dstmpde->wire_count--;
2784 continue;
2785 }
2786
2787 srcmpte = PHYS_TO_VM_PAGE(srcptepaddr & PG_FRAME);
2788 if (srcmpte->wire_count == 0)
2789 panic("pmap_copy: source page table page is unused");
2790
2791 if (va_next > end_addr)
2792 va_next = end_addr;
2793
2794 src_pte = vtopte(addr);
2795 while (addr < va_next) {
2796 pt_entry_t ptetemp;
2797 ptetemp = *src_pte;
2798 /*
2799 * we only virtual copy managed pages
2800 */
2801 if ((ptetemp & PG_MANAGED) != 0) {
2802 dstmpte = pmap_allocpte(dst_pmap, addr,
2803 M_NOWAIT);
2804 if (dstmpte == NULL)
2805 break;
2806 dst_pte = (pt_entry_t *)
2807 PHYS_TO_DMAP(VM_PAGE_TO_PHYS(dstmpte));
2808 dst_pte = &dst_pte[pmap_pte_index(addr)];
2809 if (*dst_pte == 0 &&
2810 pmap_try_insert_pv_entry(dst_pmap, addr,
2811 PHYS_TO_VM_PAGE(ptetemp & PG_FRAME))) {
2812 /*
2813 * Clear the wired, modified, and
2814 * accessed (referenced) bits
2815 * during the copy.
2816 */
2817 *dst_pte = ptetemp & ~(PG_W | PG_M |
2818 PG_A);
2819 dst_pmap->pm_stats.resident_count++;
2820 } else {
2821 free = NULL;
2822 if (pmap_unwire_pte_hold(dst_pmap,
2823 addr, dstmpte, &free)) {
2824 pmap_invalidate_page(dst_pmap,
2825 addr);
2826 pmap_free_zero_pages(free);
2827 }
2828 }
2829 if (dstmpte->wire_count >= srcmpte->wire_count)
2830 break;
2831 }
2832 addr += PAGE_SIZE;
2833 src_pte++;
2834 }
2835 }
2836 vm_page_unlock_queues();
2837 PMAP_UNLOCK(src_pmap);
2838 PMAP_UNLOCK(dst_pmap);
2839 }
2840
2841 /*
2842 * pmap_zero_page zeros the specified hardware page by mapping
2843 * the page into KVM and using bzero to clear its contents.
2844 */
2845 void
2846 pmap_zero_page(vm_page_t m)
2847 {
2848 vm_offset_t va = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m));
2849
2850 pagezero((void *)va);
2851 }
2852
2853 /*
2854 * pmap_zero_page_area zeros the specified hardware page by mapping
2855 * the page into KVM and using bzero to clear its contents.
2856 *
2857 * off and size may not cover an area beyond a single hardware page.
2858 */
2859 void
2860 pmap_zero_page_area(vm_page_t m, int off, int size)
2861 {
2862 vm_offset_t va = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m));
2863
2864 if (off == 0 && size == PAGE_SIZE)
2865 pagezero((void *)va);
2866 else
2867 bzero((char *)va + off, size);
2868 }
2869
2870 /*
2871 * pmap_zero_page_idle zeros the specified hardware page by mapping
2872 * the page into KVM and using bzero to clear its contents. This
2873 * is intended to be called from the vm_pagezero process only and
2874 * outside of Giant.
2875 */
2876 void
2877 pmap_zero_page_idle(vm_page_t m)
2878 {
2879 vm_offset_t va = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m));
2880
2881 pagezero((void *)va);
2882 }
2883
2884 /*
2885 * pmap_copy_page copies the specified (machine independent)
2886 * page by mapping the page into virtual memory and using
2887 * bcopy to copy the page, one machine dependent page at a
2888 * time.
2889 */
2890 void
2891 pmap_copy_page(vm_page_t msrc, vm_page_t mdst)
2892 {
2893 vm_offset_t src = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(msrc));
2894 vm_offset_t dst = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(mdst));
2895
2896 pagecopy((void *)src, (void *)dst);
2897 }
2898
2899 /*
2900 * Returns true if the pmap's pv is one of the first
2901 * 16 pvs linked to from this page. This count may
2902 * be changed upwards or downwards in the future; it
2903 * is only necessary that true be returned for a small
2904 * subset of pmaps for proper page aging.
2905 */
2906 boolean_t
2907 pmap_page_exists_quick(pmap_t pmap, vm_page_t m)
2908 {
2909 pv_entry_t pv;
2910 int loops = 0;
2911
2912 if (m->flags & PG_FICTITIOUS)
2913 return FALSE;
2914
2915 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
2916 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
2917 if (PV_PMAP(pv) == pmap) {
2918 return TRUE;
2919 }
2920 loops++;
2921 if (loops >= 16)
2922 break;
2923 }
2924 return (FALSE);
2925 }
2926
2927 /*
2928 * Remove all pages from specified address space
2929 * this aids process exit speeds. Also, this code
2930 * is special cased for current process only, but
2931 * can have the more generic (and slightly slower)
2932 * mode enabled. This is much faster than pmap_remove
2933 * in the case of running down an entire address space.
2934 */
2935 void
2936 pmap_remove_pages(pmap_t pmap)
2937 {
2938 pt_entry_t *pte, tpte;
2939 vm_page_t m, free = NULL;
2940 pv_entry_t pv;
2941 struct pv_chunk *pc, *npc;
2942 int field, idx;
2943 int64_t bit;
2944 uint64_t inuse, bitmask;
2945 int allfree;
2946
2947 if (pmap != vmspace_pmap(curthread->td_proc->p_vmspace)) {
2948 printf("warning: pmap_remove_pages called with non-current pmap\n");
2949 return;
2950 }
2951 vm_page_lock_queues();
2952 PMAP_LOCK(pmap);
2953 TAILQ_FOREACH_SAFE(pc, &pmap->pm_pvchunk, pc_list, npc) {
2954 allfree = 1;
2955 for (field = 0; field < _NPCM; field++) {
2956 inuse = (~(pc->pc_map[field])) & pc_freemask[field];
2957 while (inuse != 0) {
2958 bit = bsfq(inuse);
2959 bitmask = 1UL << bit;
2960 idx = field * 64 + bit;
2961 pv = &pc->pc_pventry[idx];
2962 inuse &= ~bitmask;
2963
2964 pte = vtopte(pv->pv_va);
2965 tpte = *pte;
2966
2967 if (tpte == 0) {
2968 printf(
2969 "TPTE at %p IS ZERO @ VA %08lx\n",
2970 pte, pv->pv_va);
2971 panic("bad pte");
2972 }
2973
2974 /*
2975 * We cannot remove wired pages from a process' mapping at this time
2976 */
2977 if (tpte & PG_W) {
2978 allfree = 0;
2979 continue;
2980 }
2981
2982 m = PHYS_TO_VM_PAGE(tpte & PG_FRAME);
2983 KASSERT(m->phys_addr == (tpte & PG_FRAME),
2984 ("vm_page_t %p phys_addr mismatch %016jx %016jx",
2985 m, (uintmax_t)m->phys_addr,
2986 (uintmax_t)tpte));
2987
2988 KASSERT(m < &vm_page_array[vm_page_array_size],
2989 ("pmap_remove_pages: bad tpte %#jx",
2990 (uintmax_t)tpte));
2991
2992 pmap->pm_stats.resident_count--;
2993
2994 pte_clear(pte);
2995
2996 /*
2997 * Update the vm_page_t clean/reference bits.
2998 */
2999 if (tpte & PG_M)
3000 vm_page_dirty(m);
3001
3002 /* Mark free */
3003 PV_STAT(pv_entry_frees++);
3004 PV_STAT(pv_entry_spare++);
3005 pv_entry_count--;
3006 pc->pc_map[field] |= bitmask;
3007 m->md.pv_list_count--;
3008 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
3009 if (TAILQ_EMPTY(&m->md.pv_list))
3010 vm_page_flag_clear(m, PG_WRITEABLE);
3011 pmap_unuse_pt(pmap, pv->pv_va,
3012 *vtopde(pv->pv_va), &free);
3013 }
3014 }
3015 if (allfree) {
3016 PV_STAT(pv_entry_spare -= _NPCPV);
3017 PV_STAT(pc_chunk_count--);
3018 PV_STAT(pc_chunk_frees++);
3019 TAILQ_REMOVE(&pmap->pm_pvchunk, pc, pc_list);
3020 m = PHYS_TO_VM_PAGE(DMAP_TO_PHYS((vm_offset_t)pc));
3021 dump_drop_page(m->phys_addr);
3022 vm_page_free(m);
3023 }
3024 }
3025 pmap_invalidate_all(pmap);
3026 vm_page_unlock_queues();
3027 PMAP_UNLOCK(pmap);
3028 pmap_free_zero_pages(free);
3029 }
3030
3031 /*
3032 * pmap_is_modified:
3033 *
3034 * Return whether or not the specified physical page was modified
3035 * in any physical maps.
3036 */
3037 boolean_t
3038 pmap_is_modified(vm_page_t m)
3039 {
3040 pv_entry_t pv;
3041 pt_entry_t *pte;
3042 pmap_t pmap;
3043 boolean_t rv;
3044
3045 rv = FALSE;
3046 if (m->flags & PG_FICTITIOUS)
3047 return (rv);
3048
3049 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
3050 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
3051 pmap = PV_PMAP(pv);
3052 PMAP_LOCK(pmap);
3053 pte = pmap_pte(pmap, pv->pv_va);
3054 rv = (*pte & PG_M) != 0;
3055 PMAP_UNLOCK(pmap);
3056 if (rv)
3057 break;
3058 }
3059 return (rv);
3060 }
3061
3062 /*
3063 * pmap_is_prefaultable:
3064 *
3065 * Return whether or not the specified virtual address is elgible
3066 * for prefault.
3067 */
3068 boolean_t
3069 pmap_is_prefaultable(pmap_t pmap, vm_offset_t addr)
3070 {
3071 pd_entry_t *pde;
3072 pt_entry_t *pte;
3073 boolean_t rv;
3074
3075 rv = FALSE;
3076 PMAP_LOCK(pmap);
3077 pde = pmap_pde(pmap, addr);
3078 if (pde != NULL && (*pde & PG_V)) {
3079 pte = vtopte(addr);
3080 rv = (*pte & PG_V) == 0;
3081 }
3082 PMAP_UNLOCK(pmap);
3083 return (rv);
3084 }
3085
3086 /*
3087 * Clear the write and modified bits in each of the given page's mappings.
3088 */
3089 void
3090 pmap_remove_write(vm_page_t m)
3091 {
3092 pv_entry_t pv;
3093 pmap_t pmap;
3094 pt_entry_t oldpte, *pte;
3095
3096 if ((m->flags & PG_FICTITIOUS) != 0 ||
3097 (m->flags & PG_WRITEABLE) == 0)
3098 return;
3099 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
3100 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
3101 pmap = PV_PMAP(pv);
3102 PMAP_LOCK(pmap);
3103 pte = pmap_pte(pmap, pv->pv_va);
3104 retry:
3105 oldpte = *pte;
3106 if (oldpte & PG_RW) {
3107 if (!atomic_cmpset_long(pte, oldpte, oldpte &
3108 ~(PG_RW | PG_M)))
3109 goto retry;
3110 if ((oldpte & PG_M) != 0)
3111 vm_page_dirty(m);
3112 pmap_invalidate_page(pmap, pv->pv_va);
3113 }
3114 PMAP_UNLOCK(pmap);
3115 }
3116 vm_page_flag_clear(m, PG_WRITEABLE);
3117 }
3118
3119 /*
3120 * pmap_ts_referenced:
3121 *
3122 * Return a count of reference bits for a page, clearing those bits.
3123 * It is not necessary for every reference bit to be cleared, but it
3124 * is necessary that 0 only be returned when there are truly no
3125 * reference bits set.
3126 *
3127 * XXX: The exact number of bits to check and clear is a matter that
3128 * should be tested and standardized at some point in the future for
3129 * optimal aging of shared pages.
3130 */
3131 int
3132 pmap_ts_referenced(vm_page_t m)
3133 {
3134 pv_entry_t pv, pvf, pvn;
3135 pmap_t pmap;
3136 pt_entry_t *pte;
3137 int rtval = 0;
3138
3139 if (m->flags & PG_FICTITIOUS)
3140 return (rtval);
3141 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
3142 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
3143 pvf = pv;
3144 do {
3145 pvn = TAILQ_NEXT(pv, pv_list);
3146 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
3147 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
3148 pmap = PV_PMAP(pv);
3149 PMAP_LOCK(pmap);
3150 pte = pmap_pte(pmap, pv->pv_va);
3151 if ((*pte & PG_A) != 0) {
3152 atomic_clear_long(pte, PG_A);
3153 pmap_invalidate_page(pmap, pv->pv_va);
3154 rtval++;
3155 if (rtval > 4)
3156 pvn = NULL;
3157 }
3158 PMAP_UNLOCK(pmap);
3159 } while ((pv = pvn) != NULL && pv != pvf);
3160 }
3161 return (rtval);
3162 }
3163
3164 /*
3165 * Clear the modify bits on the specified physical page.
3166 */
3167 void
3168 pmap_clear_modify(vm_page_t m)
3169 {
3170 pv_entry_t pv;
3171 pmap_t pmap;
3172 pt_entry_t *pte;
3173
3174 if ((m->flags & PG_FICTITIOUS) != 0)
3175 return;
3176 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
3177 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
3178 pmap = PV_PMAP(pv);
3179 PMAP_LOCK(pmap);
3180 pte = pmap_pte(pmap, pv->pv_va);
3181 if (*pte & PG_M) {
3182 atomic_clear_long(pte, PG_M);
3183 pmap_invalidate_page(pmap, pv->pv_va);
3184 }
3185 PMAP_UNLOCK(pmap);
3186 }
3187 }
3188
3189 /*
3190 * pmap_clear_reference:
3191 *
3192 * Clear the reference bit on the specified physical page.
3193 */
3194 void
3195 pmap_clear_reference(vm_page_t m)
3196 {
3197 pv_entry_t pv;
3198 pmap_t pmap;
3199 pt_entry_t *pte;
3200
3201 if ((m->flags & PG_FICTITIOUS) != 0)
3202 return;
3203 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
3204 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
3205 pmap = PV_PMAP(pv);
3206 PMAP_LOCK(pmap);
3207 pte = pmap_pte(pmap, pv->pv_va);
3208 if (*pte & PG_A) {
3209 atomic_clear_long(pte, PG_A);
3210 pmap_invalidate_page(pmap, pv->pv_va);
3211 }
3212 PMAP_UNLOCK(pmap);
3213 }
3214 }
3215
3216 /*
3217 * Miscellaneous support routines follow
3218 */
3219
3220 /* Adjust the cache mode for a 4KB page mapped via a PTE. */
3221 static __inline void
3222 pmap_pte_attr(vm_offset_t va, int mode)
3223 {
3224 pt_entry_t *pte;
3225 u_int opte, npte;
3226
3227 pte = vtopte(va);
3228
3229 /*
3230 * The cache mode bits are all in the low 32-bits of the
3231 * PTE, so we can just spin on updating the low 32-bits.
3232 */
3233 do {
3234 opte = *(u_int *)pte;
3235 npte = opte & ~(PG_PTE_PAT | PG_NC_PCD | PG_NC_PWT);
3236 npte |= pmap_cache_bits(mode, 0);
3237 } while (npte != opte && !atomic_cmpset_int((u_int *)pte, opte, npte));
3238 }
3239
3240 /* Adjust the cache mode for a 2MB page mapped via a PDE. */
3241 static __inline void
3242 pmap_pde_attr(vm_offset_t va, int mode)
3243 {
3244 pd_entry_t *pde;
3245 u_int opde, npde;
3246
3247 pde = pmap_pde(kernel_pmap, va);
3248
3249 /*
3250 * The cache mode bits are all in the low 32-bits of the
3251 * PDE, so we can just spin on updating the low 32-bits.
3252 */
3253 do {
3254 opde = *(u_int *)pde;
3255 npde = opde & ~(PG_PDE_PAT | PG_NC_PCD | PG_NC_PWT);
3256 npde |= pmap_cache_bits(mode, 1);
3257 } while (npde != opde && !atomic_cmpset_int((u_int *)pde, opde, npde));
3258 }
3259
3260 /*
3261 * Map a set of physical memory pages into the kernel virtual
3262 * address space. Return a pointer to where it is mapped. This
3263 * routine is intended to be used for mapping device memory,
3264 * NOT real memory.
3265 */
3266 void *
3267 pmap_mapdev_attr(vm_paddr_t pa, vm_size_t size, int mode)
3268 {
3269 vm_offset_t va, tmpva, offset;
3270
3271 /*
3272 * If this fits within the direct map window and use WB caching
3273 * mode, use the direct map.
3274 */
3275 if (pa < dmaplimit && (pa + size) < dmaplimit && mode == PAT_WRITE_BACK)
3276 return ((void *)PHYS_TO_DMAP(pa));
3277 offset = pa & PAGE_MASK;
3278 size = roundup(offset + size, PAGE_SIZE);
3279 va = kmem_alloc_nofault(kernel_map, size);
3280 if (!va)
3281 panic("pmap_mapdev: Couldn't alloc kernel virtual memory");
3282 pa = trunc_page(pa);
3283 for (tmpva = va; size > 0; ) {
3284 pmap_kenter_attr(tmpva, pa, mode);
3285 size -= PAGE_SIZE;
3286 tmpva += PAGE_SIZE;
3287 pa += PAGE_SIZE;
3288 }
3289 pmap_invalidate_range(kernel_pmap, va, tmpva);
3290 pmap_invalidate_cache();
3291 return ((void *)(va + offset));
3292 }
3293
3294 void *
3295 pmap_mapdev(vm_paddr_t pa, vm_size_t size)
3296 {
3297
3298 return (pmap_mapdev_attr(pa, size, PAT_UNCACHEABLE));
3299 }
3300
3301 void *
3302 pmap_mapbios(vm_paddr_t pa, vm_size_t size)
3303 {
3304
3305 return (pmap_mapdev_attr(pa, size, PAT_WRITE_BACK));
3306 }
3307
3308 void
3309 pmap_unmapdev(vm_offset_t va, vm_size_t size)
3310 {
3311 vm_offset_t base, offset, tmpva;
3312
3313 /* If we gave a direct map region in pmap_mapdev, do nothing */
3314 if (va >= DMAP_MIN_ADDRESS && va < DMAP_MAX_ADDRESS)
3315 return;
3316 base = trunc_page(va);
3317 offset = va & PAGE_MASK;
3318 size = roundup(offset + size, PAGE_SIZE);
3319 for (tmpva = base; tmpva < (base + size); tmpva += PAGE_SIZE)
3320 pmap_kremove(tmpva);
3321 pmap_invalidate_range(kernel_pmap, va, tmpva);
3322 kmem_free(kernel_map, base, size);
3323 }
3324
3325 int
3326 pmap_change_attr(va, size, mode)
3327 vm_offset_t va;
3328 vm_size_t size;
3329 int mode;
3330 {
3331 vm_offset_t base, offset, tmpva;
3332 pd_entry_t *pde;
3333 pt_entry_t *pte;
3334
3335 base = trunc_page(va);
3336 offset = va & PAGE_MASK;
3337 size = roundup(offset + size, PAGE_SIZE);
3338
3339 /* Only supported on kernel virtual addresses. */
3340 if (base <= VM_MAXUSER_ADDRESS)
3341 return (EINVAL);
3342
3343 /*
3344 * XXX: We have to support tearing 2MB pages down into 4k pages if
3345 * needed here.
3346 */
3347 /* Pages that aren't mapped aren't supported. */
3348 for (tmpva = base; tmpva < (base + size); ) {
3349 pde = pmap_pde(kernel_pmap, tmpva);
3350 if (*pde == 0)
3351 return (EINVAL);
3352 if (*pde & PG_PS) {
3353 /* Handle 2MB pages that are completely contained. */
3354 if (size >= NBPDR) {
3355 tmpva += NBPDR;
3356 continue;
3357 }
3358 return (EINVAL);
3359 }
3360 pte = vtopte(va);
3361 if (*pte == 0)
3362 return (EINVAL);
3363 tmpva += PAGE_SIZE;
3364 }
3365
3366 /*
3367 * Ok, all the pages exist, so run through them updating their
3368 * cache mode.
3369 */
3370 for (tmpva = base; size > 0; ) {
3371 pde = pmap_pde(kernel_pmap, tmpva);
3372 if (*pde & PG_PS) {
3373 pmap_pde_attr(tmpva, mode);
3374 tmpva += NBPDR;
3375 size -= NBPDR;
3376 } else {
3377 pmap_pte_attr(tmpva, mode);
3378 tmpva += PAGE_SIZE;
3379 size -= PAGE_SIZE;
3380 }
3381 }
3382
3383 /*
3384 * Flush CPU caches to make sure any data isn't cached that shouldn't
3385 * be, etc.
3386 */
3387 pmap_invalidate_range(kernel_pmap, base, tmpva);
3388 pmap_invalidate_cache();
3389 return (0);
3390 }
3391
3392 /*
3393 * perform the pmap work for mincore
3394 */
3395 int
3396 pmap_mincore(pmap_t pmap, vm_offset_t addr)
3397 {
3398 pt_entry_t *ptep, pte;
3399 vm_page_t m;
3400 int val = 0;
3401
3402 PMAP_LOCK(pmap);
3403 ptep = pmap_pte(pmap, addr);
3404 pte = (ptep != NULL) ? *ptep : 0;
3405 PMAP_UNLOCK(pmap);
3406
3407 if (pte != 0) {
3408 vm_paddr_t pa;
3409
3410 val = MINCORE_INCORE;
3411 if ((pte & PG_MANAGED) == 0)
3412 return val;
3413
3414 pa = pte & PG_FRAME;
3415
3416 m = PHYS_TO_VM_PAGE(pa);
3417
3418 /*
3419 * Modified by us
3420 */
3421 if (pte & PG_M)
3422 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER;
3423 else {
3424 /*
3425 * Modified by someone else
3426 */
3427 vm_page_lock_queues();
3428 if (m->dirty || pmap_is_modified(m))
3429 val |= MINCORE_MODIFIED_OTHER;
3430 vm_page_unlock_queues();
3431 }
3432 /*
3433 * Referenced by us
3434 */
3435 if (pte & PG_A)
3436 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER;
3437 else {
3438 /*
3439 * Referenced by someone else
3440 */
3441 vm_page_lock_queues();
3442 if ((m->flags & PG_REFERENCED) ||
3443 pmap_ts_referenced(m)) {
3444 val |= MINCORE_REFERENCED_OTHER;
3445 vm_page_flag_set(m, PG_REFERENCED);
3446 }
3447 vm_page_unlock_queues();
3448 }
3449 }
3450 return val;
3451 }
3452
3453 void
3454 pmap_activate(struct thread *td)
3455 {
3456 pmap_t pmap, oldpmap;
3457 u_int64_t cr3;
3458
3459 critical_enter();
3460 pmap = vmspace_pmap(td->td_proc->p_vmspace);
3461 oldpmap = PCPU_GET(curpmap);
3462 #ifdef SMP
3463 if (oldpmap) /* XXX FIXME */
3464 atomic_clear_int(&oldpmap->pm_active, PCPU_GET(cpumask));
3465 atomic_set_int(&pmap->pm_active, PCPU_GET(cpumask));
3466 #else
3467 if (oldpmap) /* XXX FIXME */
3468 oldpmap->pm_active &= ~PCPU_GET(cpumask);
3469 pmap->pm_active |= PCPU_GET(cpumask);
3470 #endif
3471 cr3 = vtophys(pmap->pm_pml4);
3472 td->td_pcb->pcb_cr3 = cr3;
3473 load_cr3(cr3);
3474 critical_exit();
3475 }
3476
3477 vm_offset_t
3478 pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size)
3479 {
3480
3481 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) {
3482 return addr;
3483 }
3484
3485 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1);
3486 return addr;
3487 }
Cache object: 8d9343566b232477b562abd441d93160
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