FreeBSD/Linux Kernel Cross Reference
sys/i386/i386/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 *
9 * This code is derived from software contributed to Berkeley by
10 * the Systems Programming Group of the University of Utah Computer
11 * Science Department and William Jolitz of UUNET Technologies Inc.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. All advertising materials mentioning features or use of this software
22 * must display the following acknowledgement:
23 * This product includes software developed by the University of
24 * California, Berkeley and its contributors.
25 * 4. Neither the name of the University nor the names of its contributors
26 * may be used to endorse or promote products derived from this software
27 * without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 * SUCH DAMAGE.
40 *
41 * from: @(#)pmap.c 7.7 (Berkeley) 5/12/91
42 */
43 /*-
44 * Copyright (c) 2003 Networks Associates Technology, Inc.
45 * All rights reserved.
46 *
47 * This software was developed for the FreeBSD Project by Jake Burkholder,
48 * Safeport Network Services, and Network Associates Laboratories, the
49 * Security Research Division of Network Associates, Inc. under
50 * DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA
51 * CHATS research program.
52 *
53 * Redistribution and use in source and binary forms, with or without
54 * modification, are permitted provided that the following conditions
55 * are met:
56 * 1. Redistributions of source code must retain the above copyright
57 * notice, this list of conditions and the following disclaimer.
58 * 2. Redistributions in binary form must reproduce the above copyright
59 * notice, this list of conditions and the following disclaimer in the
60 * documentation and/or other materials provided with the distribution.
61 *
62 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
63 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
64 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
65 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
66 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
67 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
68 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
69 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
70 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
71 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
72 * SUCH DAMAGE.
73 */
74
75 #include <sys/cdefs.h>
76 __FBSDID("$FreeBSD: releng/5.4/sys/i386/i386/pmap.c 145335 2005-04-20 19:11:07Z cvs2svn $");
77
78 /*
79 * Manages physical address maps.
80 *
81 * In addition to hardware address maps, this
82 * module is called upon to provide software-use-only
83 * maps which may or may not be stored in the same
84 * form as hardware maps. These pseudo-maps are
85 * used to store intermediate results from copy
86 * operations to and from address spaces.
87 *
88 * Since the information managed by this module is
89 * also stored by the logical address mapping module,
90 * this module may throw away valid virtual-to-physical
91 * mappings at almost any time. However, invalidations
92 * of virtual-to-physical mappings must be done as
93 * requested.
94 *
95 * In order to cope with hardware architectures which
96 * make virtual-to-physical map invalidates expensive,
97 * this module may delay invalidate or reduced protection
98 * operations until such time as they are actually
99 * necessary. This module is given full information as
100 * to which processors are currently using which maps,
101 * and to when physical maps must be made correct.
102 */
103
104 #include "opt_cpu.h"
105 #include "opt_pmap.h"
106 #include "opt_msgbuf.h"
107 #include "opt_kstack_pages.h"
108
109 #include <sys/param.h>
110 #include <sys/systm.h>
111 #include <sys/kernel.h>
112 #include <sys/lock.h>
113 #include <sys/malloc.h>
114 #include <sys/mman.h>
115 #include <sys/msgbuf.h>
116 #include <sys/mutex.h>
117 #include <sys/proc.h>
118 #include <sys/sx.h>
119 #include <sys/vmmeter.h>
120 #include <sys/sched.h>
121 #include <sys/sysctl.h>
122 #ifdef SMP
123 #include <sys/smp.h>
124 #endif
125
126 #include <vm/vm.h>
127 #include <vm/vm_param.h>
128 #include <vm/vm_kern.h>
129 #include <vm/vm_page.h>
130 #include <vm/vm_map.h>
131 #include <vm/vm_object.h>
132 #include <vm/vm_extern.h>
133 #include <vm/vm_pageout.h>
134 #include <vm/vm_pager.h>
135 #include <vm/uma.h>
136
137 #include <machine/cpu.h>
138 #include <machine/cputypes.h>
139 #include <machine/md_var.h>
140 #include <machine/pcb.h>
141 #include <machine/specialreg.h>
142 #ifdef SMP
143 #include <machine/smp.h>
144 #endif
145
146 #if !defined(CPU_ENABLE_SSE) && defined(I686_CPU)
147 #define CPU_ENABLE_SSE
148 #endif
149 #if defined(CPU_DISABLE_SSE)
150 #undef CPU_ENABLE_SSE
151 #endif
152
153 #ifndef PMAP_SHPGPERPROC
154 #define PMAP_SHPGPERPROC 200
155 #endif
156
157 #if defined(DIAGNOSTIC)
158 #define PMAP_DIAGNOSTIC
159 #endif
160
161 #define MINPV 2048
162
163 #if !defined(PMAP_DIAGNOSTIC)
164 #define PMAP_INLINE __inline
165 #else
166 #define PMAP_INLINE
167 #endif
168
169 /*
170 * Get PDEs and PTEs for user/kernel address space
171 */
172 #define pmap_pde(m, v) (&((m)->pm_pdir[(vm_offset_t)(v) >> PDRSHIFT]))
173 #define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT])
174
175 #define pmap_pde_v(pte) ((*(int *)pte & PG_V) != 0)
176 #define pmap_pte_w(pte) ((*(int *)pte & PG_W) != 0)
177 #define pmap_pte_m(pte) ((*(int *)pte & PG_M) != 0)
178 #define pmap_pte_u(pte) ((*(int *)pte & PG_A) != 0)
179 #define pmap_pte_v(pte) ((*(int *)pte & PG_V) != 0)
180
181 #define pmap_pte_set_w(pte, v) ((v) ? atomic_set_int((u_int *)(pte), PG_W) : \
182 atomic_clear_int((u_int *)(pte), PG_W))
183 #define pmap_pte_set_prot(pte, v) ((*(int *)pte &= ~PG_PROT), (*(int *)pte |= (v)))
184
185 struct pmap kernel_pmap_store;
186 LIST_HEAD(pmaplist, pmap);
187 static struct pmaplist allpmaps;
188 static struct mtx allpmaps_lock;
189
190 vm_paddr_t avail_end; /* PA of last available physical page */
191 vm_offset_t virtual_avail; /* VA of first avail page (after kernel bss) */
192 vm_offset_t virtual_end; /* VA of last avail page (end of kernel AS) */
193 static boolean_t pmap_initialized = FALSE; /* Has pmap_init completed? */
194 int pgeflag = 0; /* PG_G or-in */
195 int pseflag = 0; /* PG_PS or-in */
196
197 static int nkpt;
198 vm_offset_t kernel_vm_end;
199 extern u_int32_t KERNend;
200
201 #ifdef PAE
202 static uma_zone_t pdptzone;
203 #endif
204
205 /*
206 * Data for the pv entry allocation mechanism
207 */
208 static uma_zone_t pvzone;
209 static struct vm_object pvzone_obj;
210 static int pv_entry_count = 0, pv_entry_max = 0, pv_entry_high_water = 0;
211 int pmap_pagedaemon_waken;
212
213 /*
214 * All those kernel PT submaps that BSD is so fond of
215 */
216 struct sysmaps {
217 struct mtx lock;
218 pt_entry_t *CMAP1;
219 pt_entry_t *CMAP2;
220 caddr_t CADDR1;
221 caddr_t CADDR2;
222 };
223 static struct sysmaps sysmaps_pcpu[MAXCPU];
224 pt_entry_t *CMAP1 = 0;
225 static pt_entry_t *CMAP3;
226 caddr_t CADDR1 = 0, ptvmmap = 0;
227 static caddr_t CADDR3;
228 struct msgbuf *msgbufp = 0;
229
230 /*
231 * Crashdump maps.
232 */
233 static caddr_t crashdumpmap;
234
235 #ifdef SMP
236 extern pt_entry_t *SMPpt;
237 #endif
238 static pt_entry_t *PMAP1 = 0, *PMAP2;
239 static pt_entry_t *PADDR1 = 0, *PADDR2;
240 #ifdef SMP
241 static int PMAP1cpu;
242 static int PMAP1changedcpu;
243 SYSCTL_INT(_debug, OID_AUTO, PMAP1changedcpu, CTLFLAG_RD,
244 &PMAP1changedcpu, 0,
245 "Number of times pmap_pte_quick changed CPU with same PMAP1");
246 #endif
247 static int PMAP1changed;
248 SYSCTL_INT(_debug, OID_AUTO, PMAP1changed, CTLFLAG_RD,
249 &PMAP1changed, 0,
250 "Number of times pmap_pte_quick changed PMAP1");
251 static int PMAP1unchanged;
252 SYSCTL_INT(_debug, OID_AUTO, PMAP1unchanged, CTLFLAG_RD,
253 &PMAP1unchanged, 0,
254 "Number of times pmap_pte_quick didn't change PMAP1");
255 static struct mtx PMAP2mutex;
256
257 static PMAP_INLINE void free_pv_entry(pv_entry_t pv);
258 static pv_entry_t get_pv_entry(void);
259 static void pmap_clear_ptes(vm_page_t m, int bit);
260
261 static int pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t sva);
262 static void pmap_remove_page(struct pmap *pmap, vm_offset_t va);
263 static int pmap_remove_entry(struct pmap *pmap, vm_page_t m,
264 vm_offset_t va);
265 static void pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t m);
266
267 static vm_page_t pmap_allocpte(pmap_t pmap, vm_offset_t va, int flags);
268
269 static vm_page_t _pmap_allocpte(pmap_t pmap, unsigned ptepindex, int flags);
270 static int _pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m);
271 static pt_entry_t *pmap_pte_quick(pmap_t pmap, vm_offset_t va);
272 static void pmap_pte_release(pt_entry_t *pte);
273 static int pmap_unuse_pt(pmap_t, vm_offset_t);
274 static vm_offset_t pmap_kmem_choose(vm_offset_t addr);
275 #ifdef PAE
276 static void *pmap_pdpt_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait);
277 #endif
278
279 CTASSERT(1 << PDESHIFT == sizeof(pd_entry_t));
280 CTASSERT(1 << PTESHIFT == sizeof(pt_entry_t));
281
282 /*
283 * Move the kernel virtual free pointer to the next
284 * 4MB. This is used to help improve performance
285 * by using a large (4MB) page for much of the kernel
286 * (.text, .data, .bss)
287 */
288 static vm_offset_t
289 pmap_kmem_choose(vm_offset_t addr)
290 {
291 vm_offset_t newaddr = addr;
292
293 #ifndef DISABLE_PSE
294 if (cpu_feature & CPUID_PSE)
295 newaddr = (addr + PDRMASK) & ~PDRMASK;
296 #endif
297 return newaddr;
298 }
299
300 /*
301 * Bootstrap the system enough to run with virtual memory.
302 *
303 * On the i386 this is called after mapping has already been enabled
304 * and just syncs the pmap module with what has already been done.
305 * [We can't call it easily with mapping off since the kernel is not
306 * mapped with PA == VA, hence we would have to relocate every address
307 * from the linked base (virtual) address "KERNBASE" to the actual
308 * (physical) address starting relative to 0]
309 */
310 void
311 pmap_bootstrap(firstaddr, loadaddr)
312 vm_paddr_t firstaddr;
313 vm_paddr_t loadaddr;
314 {
315 vm_offset_t va;
316 pt_entry_t *pte, *unused;
317 struct sysmaps *sysmaps;
318 int i;
319
320 /*
321 * XXX The calculation of virtual_avail is wrong. It's NKPT*PAGE_SIZE too
322 * large. It should instead be correctly calculated in locore.s and
323 * not based on 'first' (which is a physical address, not a virtual
324 * address, for the start of unused physical memory). The kernel
325 * page tables are NOT double mapped and thus should not be included
326 * in this calculation.
327 */
328 virtual_avail = (vm_offset_t) KERNBASE + firstaddr;
329 virtual_avail = pmap_kmem_choose(virtual_avail);
330
331 virtual_end = VM_MAX_KERNEL_ADDRESS;
332
333 /*
334 * Initialize the kernel pmap (which is statically allocated).
335 */
336 PMAP_LOCK_INIT(kernel_pmap);
337 kernel_pmap->pm_pdir = (pd_entry_t *) (KERNBASE + (u_int)IdlePTD);
338 #ifdef PAE
339 kernel_pmap->pm_pdpt = (pdpt_entry_t *) (KERNBASE + (u_int)IdlePDPT);
340 #endif
341 kernel_pmap->pm_active = -1; /* don't allow deactivation */
342 TAILQ_INIT(&kernel_pmap->pm_pvlist);
343 LIST_INIT(&allpmaps);
344 mtx_init(&allpmaps_lock, "allpmaps", NULL, MTX_SPIN);
345 mtx_lock_spin(&allpmaps_lock);
346 LIST_INSERT_HEAD(&allpmaps, kernel_pmap, pm_list);
347 mtx_unlock_spin(&allpmaps_lock);
348 nkpt = NKPT;
349
350 /*
351 * Reserve some special page table entries/VA space for temporary
352 * mapping of pages.
353 */
354 #define SYSMAP(c, p, v, n) \
355 v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n);
356
357 va = virtual_avail;
358 pte = vtopte(va);
359
360 /*
361 * CMAP1/CMAP2 are used for zeroing and copying pages.
362 * CMAP3 is used for the idle process page zeroing.
363 */
364 for (i = 0; i < MAXCPU; i++) {
365 sysmaps = &sysmaps_pcpu[i];
366 mtx_init(&sysmaps->lock, "SYSMAPS", NULL, MTX_DEF);
367 SYSMAP(caddr_t, sysmaps->CMAP1, sysmaps->CADDR1, 1)
368 SYSMAP(caddr_t, sysmaps->CMAP2, sysmaps->CADDR2, 1)
369 }
370 SYSMAP(caddr_t, CMAP1, CADDR1, 1)
371 SYSMAP(caddr_t, CMAP3, CADDR3, 1)
372 *CMAP3 = 0;
373
374 /*
375 * Crashdump maps.
376 */
377 SYSMAP(caddr_t, unused, crashdumpmap, MAXDUMPPGS)
378
379 /*
380 * ptvmmap is used for reading arbitrary physical pages via /dev/mem.
381 */
382 SYSMAP(caddr_t, unused, ptvmmap, 1)
383
384 /*
385 * msgbufp is used to map the system message buffer.
386 */
387 SYSMAP(struct msgbuf *, unused, msgbufp, atop(round_page(MSGBUF_SIZE)))
388
389 /*
390 * ptemap is used for pmap_pte_quick
391 */
392 SYSMAP(pt_entry_t *, PMAP1, PADDR1, 1);
393 SYSMAP(pt_entry_t *, PMAP2, PADDR2, 1);
394
395 mtx_init(&PMAP2mutex, "PMAP2", NULL, MTX_DEF);
396
397 virtual_avail = va;
398
399 *CMAP1 = 0;
400 for (i = 0; i < NKPT; i++)
401 PTD[i] = 0;
402
403 /* Turn on PG_G on kernel page(s) */
404 pmap_set_pg();
405 }
406
407 /*
408 * Set PG_G on kernel pages. Only the BSP calls this when SMP is turned on.
409 */
410 void
411 pmap_set_pg(void)
412 {
413 pd_entry_t pdir;
414 pt_entry_t *pte;
415 vm_offset_t va, endva;
416 int i;
417
418 if (pgeflag == 0)
419 return;
420
421 i = KERNLOAD/NBPDR;
422 endva = KERNBASE + KERNend;
423
424 if (pseflag) {
425 va = KERNBASE + KERNLOAD;
426 while (va < endva) {
427 pdir = kernel_pmap->pm_pdir[KPTDI+i];
428 pdir |= pgeflag;
429 kernel_pmap->pm_pdir[KPTDI+i] = PTD[KPTDI+i] = pdir;
430 invltlb(); /* Play it safe, invltlb() every time */
431 i++;
432 va += NBPDR;
433 }
434 } else {
435 va = (vm_offset_t)btext;
436 while (va < endva) {
437 pte = vtopte(va);
438 if (*pte)
439 *pte |= pgeflag;
440 invltlb(); /* Play it safe, invltlb() every time */
441 va += PAGE_SIZE;
442 }
443 }
444 }
445
446 #ifdef PAE
447
448 static MALLOC_DEFINE(M_PMAPPDPT, "pmap", "pmap pdpt");
449
450 static void *
451 pmap_pdpt_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait)
452 {
453 *flags = UMA_SLAB_PRIV;
454 return (contigmalloc(PAGE_SIZE, M_PMAPPDPT, 0, 0x0ULL, 0xffffffffULL,
455 1, 0));
456 }
457 #endif
458
459 /*
460 * Initialize the pmap module.
461 * Called by vm_init, to initialize any structures that the pmap
462 * system needs to map virtual memory.
463 * pmap_init has been enhanced to support in a fairly consistant
464 * way, discontiguous physical memory.
465 */
466 void
467 pmap_init(void)
468 {
469 int i;
470
471 /*
472 * Allocate memory for random pmap data structures. Includes the
473 * pv_head_table.
474 */
475
476 for(i = 0; i < vm_page_array_size; i++) {
477 vm_page_t m;
478
479 m = &vm_page_array[i];
480 TAILQ_INIT(&m->md.pv_list);
481 m->md.pv_list_count = 0;
482 }
483
484 /*
485 * init the pv free list
486 */
487 pvzone = uma_zcreate("PV ENTRY", sizeof (struct pv_entry), NULL, NULL,
488 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM | UMA_ZONE_NOFREE);
489 uma_prealloc(pvzone, MINPV);
490
491 #ifdef PAE
492 pdptzone = uma_zcreate("PDPT", NPGPTD * sizeof(pdpt_entry_t), NULL,
493 NULL, NULL, NULL, (NPGPTD * sizeof(pdpt_entry_t)) - 1,
494 UMA_ZONE_VM | UMA_ZONE_NOFREE);
495 uma_zone_set_allocf(pdptzone, pmap_pdpt_allocf);
496 #endif
497
498 /*
499 * Now it is safe to enable pv_table recording.
500 */
501 pmap_initialized = TRUE;
502 }
503
504 /*
505 * Initialize the address space (zone) for the pv_entries. Set a
506 * high water mark so that the system can recover from excessive
507 * numbers of pv entries.
508 */
509 void
510 pmap_init2()
511 {
512 int shpgperproc = PMAP_SHPGPERPROC;
513
514 TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc);
515 pv_entry_max = shpgperproc * maxproc + vm_page_array_size;
516 TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max);
517 pv_entry_high_water = 9 * (pv_entry_max / 10);
518 uma_zone_set_obj(pvzone, &pvzone_obj, pv_entry_max);
519 }
520
521
522 /***************************************************
523 * Low level helper routines.....
524 ***************************************************/
525
526 #if defined(PMAP_DIAGNOSTIC)
527
528 /*
529 * This code checks for non-writeable/modified pages.
530 * This should be an invalid condition.
531 */
532 static int
533 pmap_nw_modified(pt_entry_t ptea)
534 {
535 int pte;
536
537 pte = (int) ptea;
538
539 if ((pte & (PG_M|PG_RW)) == PG_M)
540 return 1;
541 else
542 return 0;
543 }
544 #endif
545
546
547 /*
548 * this routine defines the region(s) of memory that should
549 * not be tested for the modified bit.
550 */
551 static PMAP_INLINE int
552 pmap_track_modified(vm_offset_t va)
553 {
554 if ((va < kmi.clean_sva) || (va >= kmi.clean_eva))
555 return 1;
556 else
557 return 0;
558 }
559
560 #ifdef I386_CPU
561 /*
562 * i386 only has "invalidate everything" and no SMP to worry about.
563 */
564 PMAP_INLINE void
565 pmap_invalidate_page(pmap_t pmap, vm_offset_t va)
566 {
567
568 if (pmap == kernel_pmap || pmap->pm_active)
569 invltlb();
570 }
571
572 PMAP_INLINE void
573 pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
574 {
575
576 if (pmap == kernel_pmap || pmap->pm_active)
577 invltlb();
578 }
579
580 PMAP_INLINE void
581 pmap_invalidate_all(pmap_t pmap)
582 {
583
584 if (pmap == kernel_pmap || pmap->pm_active)
585 invltlb();
586 }
587 #else /* !I386_CPU */
588 #ifdef SMP
589 /*
590 * For SMP, these functions have to use the IPI mechanism for coherence.
591 */
592 void
593 pmap_invalidate_page(pmap_t pmap, vm_offset_t va)
594 {
595 u_int cpumask;
596 u_int other_cpus;
597
598 if (smp_started) {
599 if (!(read_eflags() & PSL_I))
600 panic("%s: interrupts disabled", __func__);
601 mtx_lock_spin(&smp_ipi_mtx);
602 } else
603 critical_enter();
604 /*
605 * We need to disable interrupt preemption but MUST NOT have
606 * interrupts disabled here.
607 * XXX we may need to hold schedlock to get a coherent pm_active
608 * XXX critical sections disable interrupts again
609 */
610 if (pmap == kernel_pmap || pmap->pm_active == all_cpus) {
611 invlpg(va);
612 smp_invlpg(va);
613 } else {
614 cpumask = PCPU_GET(cpumask);
615 other_cpus = PCPU_GET(other_cpus);
616 if (pmap->pm_active & cpumask)
617 invlpg(va);
618 if (pmap->pm_active & other_cpus)
619 smp_masked_invlpg(pmap->pm_active & other_cpus, va);
620 }
621 if (smp_started)
622 mtx_unlock_spin(&smp_ipi_mtx);
623 else
624 critical_exit();
625 }
626
627 void
628 pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
629 {
630 u_int cpumask;
631 u_int other_cpus;
632 vm_offset_t addr;
633
634 if (smp_started) {
635 if (!(read_eflags() & PSL_I))
636 panic("%s: interrupts disabled", __func__);
637 mtx_lock_spin(&smp_ipi_mtx);
638 } else
639 critical_enter();
640 /*
641 * We need to disable interrupt preemption but MUST NOT have
642 * interrupts disabled here.
643 * XXX we may need to hold schedlock to get a coherent pm_active
644 * XXX critical sections disable interrupts again
645 */
646 if (pmap == kernel_pmap || pmap->pm_active == all_cpus) {
647 for (addr = sva; addr < eva; addr += PAGE_SIZE)
648 invlpg(addr);
649 smp_invlpg_range(sva, eva);
650 } else {
651 cpumask = PCPU_GET(cpumask);
652 other_cpus = PCPU_GET(other_cpus);
653 if (pmap->pm_active & cpumask)
654 for (addr = sva; addr < eva; addr += PAGE_SIZE)
655 invlpg(addr);
656 if (pmap->pm_active & other_cpus)
657 smp_masked_invlpg_range(pmap->pm_active & other_cpus,
658 sva, eva);
659 }
660 if (smp_started)
661 mtx_unlock_spin(&smp_ipi_mtx);
662 else
663 critical_exit();
664 }
665
666 void
667 pmap_invalidate_all(pmap_t pmap)
668 {
669 u_int cpumask;
670 u_int other_cpus;
671
672 if (smp_started) {
673 if (!(read_eflags() & PSL_I))
674 panic("%s: interrupts disabled", __func__);
675 mtx_lock_spin(&smp_ipi_mtx);
676 } else
677 critical_enter();
678 /*
679 * We need to disable interrupt preemption but MUST NOT have
680 * interrupts disabled here.
681 * XXX we may need to hold schedlock to get a coherent pm_active
682 * XXX critical sections disable interrupts again
683 */
684 if (pmap == kernel_pmap || pmap->pm_active == all_cpus) {
685 invltlb();
686 smp_invltlb();
687 } else {
688 cpumask = PCPU_GET(cpumask);
689 other_cpus = PCPU_GET(other_cpus);
690 if (pmap->pm_active & cpumask)
691 invltlb();
692 if (pmap->pm_active & other_cpus)
693 smp_masked_invltlb(pmap->pm_active & other_cpus);
694 }
695 if (smp_started)
696 mtx_unlock_spin(&smp_ipi_mtx);
697 else
698 critical_exit();
699 }
700 #else /* !SMP */
701 /*
702 * Normal, non-SMP, 486+ invalidation functions.
703 * We inline these within pmap.c for speed.
704 */
705 PMAP_INLINE void
706 pmap_invalidate_page(pmap_t pmap, vm_offset_t va)
707 {
708
709 if (pmap == kernel_pmap || pmap->pm_active)
710 invlpg(va);
711 }
712
713 PMAP_INLINE void
714 pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
715 {
716 vm_offset_t addr;
717
718 if (pmap == kernel_pmap || pmap->pm_active)
719 for (addr = sva; addr < eva; addr += PAGE_SIZE)
720 invlpg(addr);
721 }
722
723 PMAP_INLINE void
724 pmap_invalidate_all(pmap_t pmap)
725 {
726
727 if (pmap == kernel_pmap || pmap->pm_active)
728 invltlb();
729 }
730 #endif /* !SMP */
731 #endif /* !I386_CPU */
732
733 /*
734 * Are we current address space or kernel? N.B. We return FALSE when
735 * a pmap's page table is in use because a kernel thread is borrowing
736 * it. The borrowed page table can change spontaneously, making any
737 * dependence on its continued use subject to a race condition.
738 */
739 static __inline int
740 pmap_is_current(pmap_t pmap)
741 {
742
743 return (pmap == kernel_pmap ||
744 (pmap == vmspace_pmap(curthread->td_proc->p_vmspace) &&
745 (pmap->pm_pdir[PTDPTDI] & PG_FRAME) == (PTDpde[0] & PG_FRAME)));
746 }
747
748 /*
749 * If the given pmap is not the current or kernel pmap, the returned pte must
750 * be released by passing it to pmap_pte_release().
751 */
752 pt_entry_t *
753 pmap_pte(pmap_t pmap, vm_offset_t va)
754 {
755 pd_entry_t newpf;
756 pd_entry_t *pde;
757
758 pde = pmap_pde(pmap, va);
759 if (*pde & PG_PS)
760 return (pde);
761 if (*pde != 0) {
762 /* are we current address space or kernel? */
763 if (pmap_is_current(pmap))
764 return (vtopte(va));
765 mtx_lock(&PMAP2mutex);
766 newpf = *pde & PG_FRAME;
767 if ((*PMAP2 & PG_FRAME) != newpf) {
768 *PMAP2 = newpf | PG_RW | PG_V | PG_A | PG_M;
769 pmap_invalidate_page(kernel_pmap, (vm_offset_t)PADDR2);
770 }
771 return (PADDR2 + (i386_btop(va) & (NPTEPG - 1)));
772 }
773 return (0);
774 }
775
776 /*
777 * Releases a pte that was obtained from pmap_pte(). Be prepared for the pte
778 * being NULL.
779 */
780 static __inline void
781 pmap_pte_release(pt_entry_t *pte)
782 {
783
784 if ((pt_entry_t *)((vm_offset_t)pte & ~PAGE_MASK) == PADDR2)
785 mtx_unlock(&PMAP2mutex);
786 }
787
788 static __inline void
789 invlcaddr(void *caddr)
790 {
791 #ifdef I386_CPU
792 invltlb();
793 #else
794 invlpg((u_int)caddr);
795 #endif
796 }
797
798 /*
799 * Super fast pmap_pte routine best used when scanning
800 * the pv lists. This eliminates many coarse-grained
801 * invltlb calls. Note that many of the pv list
802 * scans are across different pmaps. It is very wasteful
803 * to do an entire invltlb for checking a single mapping.
804 *
805 * If the given pmap is not the current pmap, vm_page_queue_mtx
806 * must be held and curthread pinned to a CPU.
807 */
808 static pt_entry_t *
809 pmap_pte_quick(pmap_t pmap, vm_offset_t va)
810 {
811 pd_entry_t newpf;
812 pd_entry_t *pde;
813
814 pde = pmap_pde(pmap, va);
815 if (*pde & PG_PS)
816 return (pde);
817 if (*pde != 0) {
818 /* are we current address space or kernel? */
819 if (pmap_is_current(pmap))
820 return (vtopte(va));
821 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
822 KASSERT(curthread->td_pinned > 0, ("curthread not pinned"));
823 newpf = *pde & PG_FRAME;
824 if ((*PMAP1 & PG_FRAME) != newpf) {
825 *PMAP1 = newpf | PG_RW | PG_V | PG_A | PG_M;
826 #ifdef SMP
827 PMAP1cpu = PCPU_GET(cpuid);
828 #endif
829 invlcaddr(PADDR1);
830 PMAP1changed++;
831 } else
832 #ifdef SMP
833 if (PMAP1cpu != PCPU_GET(cpuid)) {
834 PMAP1cpu = PCPU_GET(cpuid);
835 invlcaddr(PADDR1);
836 PMAP1changedcpu++;
837 } else
838 #endif
839 PMAP1unchanged++;
840 return (PADDR1 + (i386_btop(va) & (NPTEPG - 1)));
841 }
842 return (0);
843 }
844
845 /*
846 * Routine: pmap_extract
847 * Function:
848 * Extract the physical page address associated
849 * with the given map/virtual_address pair.
850 */
851 vm_paddr_t
852 pmap_extract(pmap_t pmap, vm_offset_t va)
853 {
854 vm_paddr_t rtval;
855 pt_entry_t *pte;
856 pd_entry_t pde;
857
858 rtval = 0;
859 PMAP_LOCK(pmap);
860 pde = pmap->pm_pdir[va >> PDRSHIFT];
861 if (pde != 0) {
862 if ((pde & PG_PS) != 0) {
863 rtval = (pde & ~PDRMASK) | (va & PDRMASK);
864 PMAP_UNLOCK(pmap);
865 return rtval;
866 }
867 pte = pmap_pte(pmap, va);
868 rtval = (*pte & PG_FRAME) | (va & PAGE_MASK);
869 pmap_pte_release(pte);
870 }
871 PMAP_UNLOCK(pmap);
872 return (rtval);
873 }
874
875 /*
876 * Routine: pmap_extract_and_hold
877 * Function:
878 * Atomically extract and hold the physical page
879 * with the given pmap and virtual address pair
880 * if that mapping permits the given protection.
881 */
882 vm_page_t
883 pmap_extract_and_hold(pmap_t pmap, vm_offset_t va, vm_prot_t prot)
884 {
885 pd_entry_t pde;
886 pt_entry_t pte;
887 vm_page_t m;
888
889 m = NULL;
890 vm_page_lock_queues();
891 PMAP_LOCK(pmap);
892 pde = *pmap_pde(pmap, va);
893 if (pde != 0) {
894 if (pde & PG_PS) {
895 if ((pde & PG_RW) || (prot & VM_PROT_WRITE) == 0) {
896 m = PHYS_TO_VM_PAGE((pde & ~PDRMASK) |
897 (va & PDRMASK));
898 vm_page_hold(m);
899 }
900 } else {
901 sched_pin();
902 pte = *pmap_pte_quick(pmap, va);
903 if (pte != 0 &&
904 ((pte & PG_RW) || (prot & VM_PROT_WRITE) == 0)) {
905 m = PHYS_TO_VM_PAGE(pte & PG_FRAME);
906 vm_page_hold(m);
907 }
908 sched_unpin();
909 }
910 }
911 vm_page_unlock_queues();
912 PMAP_UNLOCK(pmap);
913 return (m);
914 }
915
916 /***************************************************
917 * Low level mapping routines.....
918 ***************************************************/
919
920 /*
921 * Add a wired page to the kva.
922 * Note: not SMP coherent.
923 */
924 PMAP_INLINE void
925 pmap_kenter(vm_offset_t va, vm_paddr_t pa)
926 {
927 pt_entry_t *pte;
928
929 pte = vtopte(va);
930 pte_store(pte, pa | PG_RW | PG_V | pgeflag);
931 }
932
933 /*
934 * Remove a page from the kernel pagetables.
935 * Note: not SMP coherent.
936 */
937 PMAP_INLINE void
938 pmap_kremove(vm_offset_t va)
939 {
940 pt_entry_t *pte;
941
942 pte = vtopte(va);
943 pte_clear(pte);
944 }
945
946 /*
947 * Used to map a range of physical addresses into kernel
948 * virtual address space.
949 *
950 * The value passed in '*virt' is a suggested virtual address for
951 * the mapping. Architectures which can support a direct-mapped
952 * physical to virtual region can return the appropriate address
953 * within that region, leaving '*virt' unchanged. Other
954 * architectures should map the pages starting at '*virt' and
955 * update '*virt' with the first usable address after the mapped
956 * region.
957 */
958 vm_offset_t
959 pmap_map(vm_offset_t *virt, vm_paddr_t start, vm_paddr_t end, int prot)
960 {
961 vm_offset_t va, sva;
962
963 va = sva = *virt;
964 while (start < end) {
965 pmap_kenter(va, start);
966 va += PAGE_SIZE;
967 start += PAGE_SIZE;
968 }
969 pmap_invalidate_range(kernel_pmap, sva, va);
970 *virt = va;
971 return (sva);
972 }
973
974
975 /*
976 * Add a list of wired pages to the kva
977 * this routine is only used for temporary
978 * kernel mappings that do not need to have
979 * page modification or references recorded.
980 * Note that old mappings are simply written
981 * over. The page *must* be wired.
982 * Note: SMP coherent. Uses a ranged shootdown IPI.
983 */
984 void
985 pmap_qenter(vm_offset_t sva, vm_page_t *m, int count)
986 {
987 vm_offset_t va;
988
989 va = sva;
990 while (count-- > 0) {
991 pmap_kenter(va, VM_PAGE_TO_PHYS(*m));
992 va += PAGE_SIZE;
993 m++;
994 }
995 pmap_invalidate_range(kernel_pmap, sva, va);
996 }
997
998 /*
999 * This routine tears out page mappings from the
1000 * kernel -- it is meant only for temporary mappings.
1001 * Note: SMP coherent. Uses a ranged shootdown IPI.
1002 */
1003 void
1004 pmap_qremove(vm_offset_t sva, int count)
1005 {
1006 vm_offset_t va;
1007
1008 va = sva;
1009 while (count-- > 0) {
1010 pmap_kremove(va);
1011 va += PAGE_SIZE;
1012 }
1013 pmap_invalidate_range(kernel_pmap, sva, va);
1014 }
1015
1016 /***************************************************
1017 * Page table page management routines.....
1018 ***************************************************/
1019
1020 /*
1021 * This routine unholds page table pages, and if the hold count
1022 * drops to zero, then it decrements the wire count.
1023 */
1024 static PMAP_INLINE int
1025 pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m)
1026 {
1027
1028 --m->wire_count;
1029 if (m->wire_count == 0)
1030 return _pmap_unwire_pte_hold(pmap, m);
1031 else
1032 return 0;
1033 }
1034
1035 static int
1036 _pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m)
1037 {
1038 vm_offset_t pteva;
1039
1040 /*
1041 * unmap the page table page
1042 */
1043 pmap->pm_pdir[m->pindex] = 0;
1044 --pmap->pm_stats.resident_count;
1045
1046 /*
1047 * Do an invltlb to make the invalidated mapping
1048 * take effect immediately.
1049 */
1050 pteva = VM_MAXUSER_ADDRESS + i386_ptob(m->pindex);
1051 pmap_invalidate_page(pmap, pteva);
1052
1053 vm_page_free_zero(m);
1054 atomic_subtract_int(&cnt.v_wire_count, 1);
1055 return 1;
1056 }
1057
1058 /*
1059 * After removing a page table entry, this routine is used to
1060 * conditionally free the page, and manage the hold/wire counts.
1061 */
1062 static int
1063 pmap_unuse_pt(pmap_t pmap, vm_offset_t va)
1064 {
1065 pd_entry_t ptepde;
1066 vm_page_t mpte;
1067
1068 if (va >= VM_MAXUSER_ADDRESS)
1069 return 0;
1070 ptepde = *pmap_pde(pmap, va);
1071 mpte = PHYS_TO_VM_PAGE(ptepde & PG_FRAME);
1072 return pmap_unwire_pte_hold(pmap, mpte);
1073 }
1074
1075 void
1076 pmap_pinit0(pmap)
1077 struct pmap *pmap;
1078 {
1079
1080 PMAP_LOCK_INIT(pmap);
1081 pmap->pm_pdir = (pd_entry_t *)(KERNBASE + (vm_offset_t)IdlePTD);
1082 #ifdef PAE
1083 pmap->pm_pdpt = (pdpt_entry_t *)(KERNBASE + (vm_offset_t)IdlePDPT);
1084 #endif
1085 pmap->pm_active = 0;
1086 PCPU_SET(curpmap, pmap);
1087 TAILQ_INIT(&pmap->pm_pvlist);
1088 bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
1089 mtx_lock_spin(&allpmaps_lock);
1090 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list);
1091 mtx_unlock_spin(&allpmaps_lock);
1092 }
1093
1094 /*
1095 * Initialize a preallocated and zeroed pmap structure,
1096 * such as one in a vmspace structure.
1097 */
1098 void
1099 pmap_pinit(pmap)
1100 register struct pmap *pmap;
1101 {
1102 vm_page_t m, ptdpg[NPGPTD];
1103 vm_paddr_t pa;
1104 static int color;
1105 int i;
1106
1107 PMAP_LOCK_INIT(pmap);
1108
1109 /*
1110 * No need to allocate page table space yet but we do need a valid
1111 * page directory table.
1112 */
1113 if (pmap->pm_pdir == NULL) {
1114 pmap->pm_pdir = (pd_entry_t *)kmem_alloc_nofault(kernel_map,
1115 NBPTD);
1116 #ifdef PAE
1117 pmap->pm_pdpt = uma_zalloc(pdptzone, M_WAITOK | M_ZERO);
1118 KASSERT(((vm_offset_t)pmap->pm_pdpt &
1119 ((NPGPTD * sizeof(pdpt_entry_t)) - 1)) == 0,
1120 ("pmap_pinit: pdpt misaligned"));
1121 KASSERT(pmap_kextract((vm_offset_t)pmap->pm_pdpt) < (4ULL<<30),
1122 ("pmap_pinit: pdpt above 4g"));
1123 #endif
1124 }
1125
1126 /*
1127 * allocate the page directory page(s)
1128 */
1129 for (i = 0; i < NPGPTD;) {
1130 m = vm_page_alloc(NULL, color++,
1131 VM_ALLOC_NORMAL | VM_ALLOC_NOOBJ | VM_ALLOC_WIRED |
1132 VM_ALLOC_ZERO);
1133 if (m == NULL)
1134 VM_WAIT;
1135 else {
1136 ptdpg[i++] = m;
1137 }
1138 }
1139
1140 pmap_qenter((vm_offset_t)pmap->pm_pdir, ptdpg, NPGPTD);
1141
1142 for (i = 0; i < NPGPTD; i++) {
1143 if ((ptdpg[i]->flags & PG_ZERO) == 0)
1144 bzero(pmap->pm_pdir + (i * NPDEPG), PAGE_SIZE);
1145 }
1146
1147 mtx_lock_spin(&allpmaps_lock);
1148 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list);
1149 mtx_unlock_spin(&allpmaps_lock);
1150 /* Wire in kernel global address entries. */
1151 /* XXX copies current process, does not fill in MPPTDI */
1152 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * sizeof(pd_entry_t));
1153 #ifdef SMP
1154 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI];
1155 #endif
1156
1157 /* install self-referential address mapping entry(s) */
1158 for (i = 0; i < NPGPTD; i++) {
1159 pa = VM_PAGE_TO_PHYS(ptdpg[i]);
1160 pmap->pm_pdir[PTDPTDI + i] = pa | PG_V | PG_RW | PG_A | PG_M;
1161 #ifdef PAE
1162 pmap->pm_pdpt[i] = pa | PG_V;
1163 #endif
1164 }
1165
1166 pmap->pm_active = 0;
1167 TAILQ_INIT(&pmap->pm_pvlist);
1168 bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
1169 }
1170
1171 /*
1172 * this routine is called if the page table page is not
1173 * mapped correctly.
1174 */
1175 static vm_page_t
1176 _pmap_allocpte(pmap_t pmap, unsigned ptepindex, int flags)
1177 {
1178 vm_paddr_t ptepa;
1179 vm_page_t m;
1180
1181 KASSERT((flags & (M_NOWAIT | M_WAITOK)) == M_NOWAIT ||
1182 (flags & (M_NOWAIT | M_WAITOK)) == M_WAITOK,
1183 ("_pmap_allocpte: flags is neither M_NOWAIT nor M_WAITOK"));
1184
1185 /*
1186 * Allocate a page table page.
1187 */
1188 if ((m = vm_page_alloc(NULL, ptepindex, VM_ALLOC_NOOBJ |
1189 VM_ALLOC_WIRED | VM_ALLOC_ZERO)) == NULL) {
1190 if (flags & M_WAITOK) {
1191 PMAP_UNLOCK(pmap);
1192 vm_page_unlock_queues();
1193 VM_WAIT;
1194 vm_page_lock_queues();
1195 PMAP_LOCK(pmap);
1196 }
1197
1198 /*
1199 * Indicate the need to retry. While waiting, the page table
1200 * page may have been allocated.
1201 */
1202 return (NULL);
1203 }
1204 if ((m->flags & PG_ZERO) == 0)
1205 pmap_zero_page(m);
1206
1207 /*
1208 * Map the pagetable page into the process address space, if
1209 * it isn't already there.
1210 */
1211
1212 pmap->pm_stats.resident_count++;
1213
1214 ptepa = VM_PAGE_TO_PHYS(m);
1215 pmap->pm_pdir[ptepindex] =
1216 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M);
1217
1218 return m;
1219 }
1220
1221 static vm_page_t
1222 pmap_allocpte(pmap_t pmap, vm_offset_t va, int flags)
1223 {
1224 unsigned ptepindex;
1225 pd_entry_t ptepa;
1226 vm_page_t m;
1227
1228 KASSERT((flags & (M_NOWAIT | M_WAITOK)) == M_NOWAIT ||
1229 (flags & (M_NOWAIT | M_WAITOK)) == M_WAITOK,
1230 ("pmap_allocpte: flags is neither M_NOWAIT nor M_WAITOK"));
1231
1232 /*
1233 * Calculate pagetable page index
1234 */
1235 ptepindex = va >> PDRSHIFT;
1236 retry:
1237 /*
1238 * Get the page directory entry
1239 */
1240 ptepa = pmap->pm_pdir[ptepindex];
1241
1242 /*
1243 * This supports switching from a 4MB page to a
1244 * normal 4K page.
1245 */
1246 if (ptepa & PG_PS) {
1247 pmap->pm_pdir[ptepindex] = 0;
1248 ptepa = 0;
1249 pmap_invalidate_all(kernel_pmap);
1250 }
1251
1252 /*
1253 * If the page table page is mapped, we just increment the
1254 * hold count, and activate it.
1255 */
1256 if (ptepa) {
1257 m = PHYS_TO_VM_PAGE(ptepa);
1258 m->wire_count++;
1259 } else {
1260 /*
1261 * Here if the pte page isn't mapped, or if it has
1262 * been deallocated.
1263 */
1264 m = _pmap_allocpte(pmap, ptepindex, flags);
1265 if (m == NULL && (flags & M_WAITOK))
1266 goto retry;
1267 }
1268 return (m);
1269 }
1270
1271
1272 /***************************************************
1273 * Pmap allocation/deallocation routines.
1274 ***************************************************/
1275
1276 #ifdef SMP
1277 /*
1278 * Deal with a SMP shootdown of other users of the pmap that we are
1279 * trying to dispose of. This can be a bit hairy.
1280 */
1281 static u_int *lazymask;
1282 static u_int lazyptd;
1283 static volatile u_int lazywait;
1284
1285 void pmap_lazyfix_action(void);
1286
1287 void
1288 pmap_lazyfix_action(void)
1289 {
1290 u_int mymask = PCPU_GET(cpumask);
1291
1292 if (rcr3() == lazyptd)
1293 load_cr3(PCPU_GET(curpcb)->pcb_cr3);
1294 atomic_clear_int(lazymask, mymask);
1295 atomic_store_rel_int(&lazywait, 1);
1296 }
1297
1298 static void
1299 pmap_lazyfix_self(u_int mymask)
1300 {
1301
1302 if (rcr3() == lazyptd)
1303 load_cr3(PCPU_GET(curpcb)->pcb_cr3);
1304 atomic_clear_int(lazymask, mymask);
1305 }
1306
1307
1308 static void
1309 pmap_lazyfix(pmap_t pmap)
1310 {
1311 u_int mymask = PCPU_GET(cpumask);
1312 u_int mask;
1313 register u_int spins;
1314
1315 while ((mask = pmap->pm_active) != 0) {
1316 spins = 50000000;
1317 mask = mask & -mask; /* Find least significant set bit */
1318 mtx_lock_spin(&smp_ipi_mtx);
1319 #ifdef PAE
1320 lazyptd = vtophys(pmap->pm_pdpt);
1321 #else
1322 lazyptd = vtophys(pmap->pm_pdir);
1323 #endif
1324 if (mask == mymask) {
1325 lazymask = &pmap->pm_active;
1326 pmap_lazyfix_self(mymask);
1327 } else {
1328 atomic_store_rel_int((u_int *)&lazymask,
1329 (u_int)&pmap->pm_active);
1330 atomic_store_rel_int(&lazywait, 0);
1331 ipi_selected(mask, IPI_LAZYPMAP);
1332 while (lazywait == 0) {
1333 ia32_pause();
1334 if (--spins == 0)
1335 break;
1336 }
1337 }
1338 mtx_unlock_spin(&smp_ipi_mtx);
1339 if (spins == 0)
1340 printf("pmap_lazyfix: spun for 50000000\n");
1341 }
1342 }
1343
1344 #else /* SMP */
1345
1346 /*
1347 * Cleaning up on uniprocessor is easy. For various reasons, we're
1348 * unlikely to have to even execute this code, including the fact
1349 * that the cleanup is deferred until the parent does a wait(2), which
1350 * means that another userland process has run.
1351 */
1352 static void
1353 pmap_lazyfix(pmap_t pmap)
1354 {
1355 u_int cr3;
1356
1357 cr3 = vtophys(pmap->pm_pdir);
1358 if (cr3 == rcr3()) {
1359 load_cr3(PCPU_GET(curpcb)->pcb_cr3);
1360 pmap->pm_active &= ~(PCPU_GET(cpumask));
1361 }
1362 }
1363 #endif /* SMP */
1364
1365 /*
1366 * Release any resources held by the given physical map.
1367 * Called when a pmap initialized by pmap_pinit is being released.
1368 * Should only be called if the map contains no valid mappings.
1369 */
1370 void
1371 pmap_release(pmap_t pmap)
1372 {
1373 vm_page_t m, ptdpg[NPGPTD];
1374 int i;
1375
1376 KASSERT(pmap->pm_stats.resident_count == 0,
1377 ("pmap_release: pmap resident count %ld != 0",
1378 pmap->pm_stats.resident_count));
1379
1380 pmap_lazyfix(pmap);
1381 mtx_lock_spin(&allpmaps_lock);
1382 LIST_REMOVE(pmap, pm_list);
1383 mtx_unlock_spin(&allpmaps_lock);
1384
1385 for (i = 0; i < NPGPTD; i++)
1386 ptdpg[i] = PHYS_TO_VM_PAGE(pmap->pm_pdir[PTDPTDI + i]);
1387
1388 bzero(pmap->pm_pdir + PTDPTDI, (nkpt + NPGPTD) *
1389 sizeof(*pmap->pm_pdir));
1390 #ifdef SMP
1391 pmap->pm_pdir[MPPTDI] = 0;
1392 #endif
1393
1394 pmap_qremove((vm_offset_t)pmap->pm_pdir, NPGPTD);
1395
1396 vm_page_lock_queues();
1397 for (i = 0; i < NPGPTD; i++) {
1398 m = ptdpg[i];
1399 #ifdef PAE
1400 KASSERT(VM_PAGE_TO_PHYS(m) == (pmap->pm_pdpt[i] & PG_FRAME),
1401 ("pmap_release: got wrong ptd page"));
1402 #endif
1403 m->wire_count--;
1404 atomic_subtract_int(&cnt.v_wire_count, 1);
1405 vm_page_free_zero(m);
1406 }
1407 vm_page_unlock_queues();
1408 PMAP_LOCK_DESTROY(pmap);
1409 }
1410
1411 static int
1412 kvm_size(SYSCTL_HANDLER_ARGS)
1413 {
1414 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE;
1415
1416 return sysctl_handle_long(oidp, &ksize, 0, req);
1417 }
1418 SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD,
1419 0, 0, kvm_size, "IU", "Size of KVM");
1420
1421 static int
1422 kvm_free(SYSCTL_HANDLER_ARGS)
1423 {
1424 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end;
1425
1426 return sysctl_handle_long(oidp, &kfree, 0, req);
1427 }
1428 SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD,
1429 0, 0, kvm_free, "IU", "Amount of KVM free");
1430
1431 /*
1432 * grow the number of kernel page table entries, if needed
1433 */
1434 void
1435 pmap_growkernel(vm_offset_t addr)
1436 {
1437 struct pmap *pmap;
1438 vm_paddr_t ptppaddr;
1439 vm_page_t nkpg;
1440 pd_entry_t newpdir;
1441 pt_entry_t *pde;
1442
1443 mtx_assert(&kernel_map->system_mtx, MA_OWNED);
1444 if (kernel_vm_end == 0) {
1445 kernel_vm_end = KERNBASE;
1446 nkpt = 0;
1447 while (pdir_pde(PTD, kernel_vm_end)) {
1448 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
1449 nkpt++;
1450 }
1451 }
1452 addr = roundup2(addr, PAGE_SIZE * NPTEPG);
1453 while (kernel_vm_end < addr) {
1454 if (pdir_pde(PTD, kernel_vm_end)) {
1455 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
1456 continue;
1457 }
1458
1459 /*
1460 * This index is bogus, but out of the way
1461 */
1462 nkpg = vm_page_alloc(NULL, nkpt,
1463 VM_ALLOC_NOOBJ | VM_ALLOC_SYSTEM | VM_ALLOC_WIRED);
1464 if (!nkpg)
1465 panic("pmap_growkernel: no memory to grow kernel");
1466
1467 nkpt++;
1468
1469 pmap_zero_page(nkpg);
1470 ptppaddr = VM_PAGE_TO_PHYS(nkpg);
1471 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M);
1472 pdir_pde(PTD, kernel_vm_end) = newpdir;
1473
1474 mtx_lock_spin(&allpmaps_lock);
1475 LIST_FOREACH(pmap, &allpmaps, pm_list) {
1476 pde = pmap_pde(pmap, kernel_vm_end);
1477 pde_store(pde, newpdir);
1478 }
1479 mtx_unlock_spin(&allpmaps_lock);
1480 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
1481 }
1482 }
1483
1484
1485 /***************************************************
1486 * page management routines.
1487 ***************************************************/
1488
1489 /*
1490 * free the pv_entry back to the free list
1491 */
1492 static PMAP_INLINE void
1493 free_pv_entry(pv_entry_t pv)
1494 {
1495 pv_entry_count--;
1496 uma_zfree(pvzone, pv);
1497 }
1498
1499 /*
1500 * get a new pv_entry, allocating a block from the system
1501 * when needed.
1502 * the memory allocation is performed bypassing the malloc code
1503 * because of the possibility of allocations at interrupt time.
1504 */
1505 static pv_entry_t
1506 get_pv_entry(void)
1507 {
1508 pv_entry_count++;
1509 if (pv_entry_high_water &&
1510 (pv_entry_count > pv_entry_high_water) &&
1511 (pmap_pagedaemon_waken == 0)) {
1512 pmap_pagedaemon_waken = 1;
1513 wakeup (&vm_pages_needed);
1514 }
1515 return uma_zalloc(pvzone, M_NOWAIT);
1516 }
1517
1518
1519 static int
1520 pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va)
1521 {
1522 pv_entry_t pv;
1523 int rtval;
1524
1525 PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1526 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1527 if (m->md.pv_list_count < pmap->pm_stats.resident_count) {
1528 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
1529 if (pmap == pv->pv_pmap && va == pv->pv_va)
1530 break;
1531 }
1532 } else {
1533 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) {
1534 if (va == pv->pv_va)
1535 break;
1536 }
1537 }
1538
1539 rtval = 0;
1540 if (pv) {
1541 rtval = pmap_unuse_pt(pmap, va);
1542 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
1543 m->md.pv_list_count--;
1544 if (TAILQ_FIRST(&m->md.pv_list) == NULL)
1545 vm_page_flag_clear(m, PG_WRITEABLE);
1546
1547 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist);
1548 free_pv_entry(pv);
1549 }
1550
1551 return rtval;
1552 }
1553
1554 /*
1555 * Create a pv entry for page at pa for
1556 * (pmap, va).
1557 */
1558 static void
1559 pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t m)
1560 {
1561 pv_entry_t pv;
1562
1563 pv = get_pv_entry();
1564 pv->pv_va = va;
1565 pv->pv_pmap = pmap;
1566
1567 PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1568 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1569 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist);
1570 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
1571 m->md.pv_list_count++;
1572 }
1573
1574 /*
1575 * pmap_remove_pte: do the things to unmap a page in a process
1576 */
1577 static int
1578 pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va)
1579 {
1580 pt_entry_t oldpte;
1581 vm_page_t m;
1582
1583 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1584 PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1585 oldpte = pte_load_clear(ptq);
1586 if (oldpte & PG_W)
1587 pmap->pm_stats.wired_count -= 1;
1588 /*
1589 * Machines that don't support invlpg, also don't support
1590 * PG_G.
1591 */
1592 if (oldpte & PG_G)
1593 pmap_invalidate_page(kernel_pmap, va);
1594 pmap->pm_stats.resident_count -= 1;
1595 if (oldpte & PG_MANAGED) {
1596 m = PHYS_TO_VM_PAGE(oldpte);
1597 if (oldpte & PG_M) {
1598 #if defined(PMAP_DIAGNOSTIC)
1599 if (pmap_nw_modified((pt_entry_t) oldpte)) {
1600 printf(
1601 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n",
1602 va, oldpte);
1603 }
1604 #endif
1605 if (pmap_track_modified(va))
1606 vm_page_dirty(m);
1607 }
1608 if (oldpte & PG_A)
1609 vm_page_flag_set(m, PG_REFERENCED);
1610 return pmap_remove_entry(pmap, m, va);
1611 } else {
1612 return pmap_unuse_pt(pmap, va);
1613 }
1614 }
1615
1616 /*
1617 * Remove a single page from a process address space
1618 */
1619 static void
1620 pmap_remove_page(pmap_t pmap, vm_offset_t va)
1621 {
1622 pt_entry_t *pte;
1623
1624 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1625 KASSERT(curthread->td_pinned > 0, ("curthread not pinned"));
1626 PMAP_LOCK_ASSERT(pmap, MA_OWNED);
1627 if ((pte = pmap_pte_quick(pmap, va)) == NULL || *pte == 0)
1628 return;
1629 pmap_remove_pte(pmap, pte, va);
1630 pmap_invalidate_page(pmap, va);
1631 }
1632
1633 /*
1634 * Remove the given range of addresses from the specified map.
1635 *
1636 * It is assumed that the start and end are properly
1637 * rounded to the page size.
1638 */
1639 void
1640 pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
1641 {
1642 vm_offset_t pdnxt;
1643 pd_entry_t ptpaddr;
1644 pt_entry_t *pte;
1645 int anyvalid;
1646
1647 /*
1648 * Perform an unsynchronized read. This is, however, safe.
1649 */
1650 if (pmap->pm_stats.resident_count == 0)
1651 return;
1652
1653 anyvalid = 0;
1654
1655 vm_page_lock_queues();
1656 sched_pin();
1657 PMAP_LOCK(pmap);
1658
1659 /*
1660 * special handling of removing one page. a very
1661 * common operation and easy to short circuit some
1662 * code.
1663 */
1664 if ((sva + PAGE_SIZE == eva) &&
1665 ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) {
1666 pmap_remove_page(pmap, sva);
1667 goto out;
1668 }
1669
1670 for (; sva < eva; sva = pdnxt) {
1671 unsigned pdirindex;
1672
1673 /*
1674 * Calculate index for next page table.
1675 */
1676 pdnxt = (sva + NBPDR) & ~PDRMASK;
1677 if (pmap->pm_stats.resident_count == 0)
1678 break;
1679
1680 pdirindex = sva >> PDRSHIFT;
1681 ptpaddr = pmap->pm_pdir[pdirindex];
1682
1683 /*
1684 * Weed out invalid mappings. Note: we assume that the page
1685 * directory table is always allocated, and in kernel virtual.
1686 */
1687 if (ptpaddr == 0)
1688 continue;
1689
1690 /*
1691 * Check for large page.
1692 */
1693 if ((ptpaddr & PG_PS) != 0) {
1694 pmap->pm_pdir[pdirindex] = 0;
1695 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
1696 anyvalid = 1;
1697 continue;
1698 }
1699
1700 /*
1701 * Limit our scan to either the end of the va represented
1702 * by the current page table page, or to the end of the
1703 * range being removed.
1704 */
1705 if (pdnxt > eva)
1706 pdnxt = eva;
1707
1708 for (; sva != pdnxt; sva += PAGE_SIZE) {
1709 if ((pte = pmap_pte_quick(pmap, sva)) == NULL ||
1710 *pte == 0)
1711 continue;
1712 anyvalid = 1;
1713 if (pmap_remove_pte(pmap, pte, sva))
1714 break;
1715 }
1716 }
1717 out:
1718 sched_unpin();
1719 vm_page_unlock_queues();
1720 if (anyvalid)
1721 pmap_invalidate_all(pmap);
1722 PMAP_UNLOCK(pmap);
1723 }
1724
1725 /*
1726 * Routine: pmap_remove_all
1727 * Function:
1728 * Removes this physical page from
1729 * all physical maps in which it resides.
1730 * Reflects back modify bits to the pager.
1731 *
1732 * Notes:
1733 * Original versions of this routine were very
1734 * inefficient because they iteratively called
1735 * pmap_remove (slow...)
1736 */
1737
1738 void
1739 pmap_remove_all(vm_page_t m)
1740 {
1741 register pv_entry_t pv;
1742 pt_entry_t *pte, tpte;
1743
1744 #if defined(PMAP_DIAGNOSTIC)
1745 /*
1746 * XXX This makes pmap_remove_all() illegal for non-managed pages!
1747 */
1748 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) {
1749 panic("pmap_remove_all: illegal for unmanaged page, va: 0x%x",
1750 VM_PAGE_TO_PHYS(m));
1751 }
1752 #endif
1753 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
1754 sched_pin();
1755 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
1756 PMAP_LOCK(pv->pv_pmap);
1757 pv->pv_pmap->pm_stats.resident_count--;
1758 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
1759 tpte = pte_load_clear(pte);
1760 if (tpte & PG_W)
1761 pv->pv_pmap->pm_stats.wired_count--;
1762 if (tpte & PG_A)
1763 vm_page_flag_set(m, PG_REFERENCED);
1764
1765 /*
1766 * Update the vm_page_t clean and reference bits.
1767 */
1768 if (tpte & PG_M) {
1769 #if defined(PMAP_DIAGNOSTIC)
1770 if (pmap_nw_modified((pt_entry_t) tpte)) {
1771 printf(
1772 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n",
1773 pv->pv_va, tpte);
1774 }
1775 #endif
1776 if (pmap_track_modified(pv->pv_va))
1777 vm_page_dirty(m);
1778 }
1779 pmap_invalidate_page(pv->pv_pmap, pv->pv_va);
1780 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist);
1781 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
1782 m->md.pv_list_count--;
1783 pmap_unuse_pt(pv->pv_pmap, pv->pv_va);
1784 PMAP_UNLOCK(pv->pv_pmap);
1785 free_pv_entry(pv);
1786 }
1787 vm_page_flag_clear(m, PG_WRITEABLE);
1788 sched_unpin();
1789 }
1790
1791 /*
1792 * Set the physical protection on the
1793 * specified range of this map as requested.
1794 */
1795 void
1796 pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
1797 {
1798 vm_offset_t pdnxt;
1799 pd_entry_t ptpaddr;
1800 int anychanged;
1801
1802 if ((prot & VM_PROT_READ) == VM_PROT_NONE) {
1803 pmap_remove(pmap, sva, eva);
1804 return;
1805 }
1806
1807 if (prot & VM_PROT_WRITE)
1808 return;
1809
1810 anychanged = 0;
1811
1812 vm_page_lock_queues();
1813 sched_pin();
1814 PMAP_LOCK(pmap);
1815 for (; sva < eva; sva = pdnxt) {
1816 unsigned obits, pbits, pdirindex;
1817
1818 pdnxt = (sva + NBPDR) & ~PDRMASK;
1819
1820 pdirindex = sva >> PDRSHIFT;
1821 ptpaddr = pmap->pm_pdir[pdirindex];
1822
1823 /*
1824 * Weed out invalid mappings. Note: we assume that the page
1825 * directory table is always allocated, and in kernel virtual.
1826 */
1827 if (ptpaddr == 0)
1828 continue;
1829
1830 /*
1831 * Check for large page.
1832 */
1833 if ((ptpaddr & PG_PS) != 0) {
1834 pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW);
1835 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
1836 anychanged = 1;
1837 continue;
1838 }
1839
1840 if (pdnxt > eva)
1841 pdnxt = eva;
1842
1843 for (; sva != pdnxt; sva += PAGE_SIZE) {
1844 pt_entry_t *pte;
1845 vm_page_t m;
1846
1847 if ((pte = pmap_pte_quick(pmap, sva)) == NULL)
1848 continue;
1849 retry:
1850 /*
1851 * Regardless of whether a pte is 32 or 64 bits in
1852 * size, PG_RW, PG_A, and PG_M are among the least
1853 * significant 32 bits.
1854 */
1855 obits = pbits = *(u_int *)pte;
1856 if (pbits & PG_MANAGED) {
1857 m = NULL;
1858 if (pbits & PG_A) {
1859 m = PHYS_TO_VM_PAGE(pbits);
1860 vm_page_flag_set(m, PG_REFERENCED);
1861 pbits &= ~PG_A;
1862 }
1863 if ((pbits & PG_M) != 0 &&
1864 pmap_track_modified(sva)) {
1865 if (m == NULL)
1866 m = PHYS_TO_VM_PAGE(pbits);
1867 vm_page_dirty(m);
1868 }
1869 }
1870
1871 pbits &= ~(PG_RW | PG_M);
1872
1873 if (pbits != obits) {
1874 if (!atomic_cmpset_int((u_int *)pte, obits,
1875 pbits))
1876 goto retry;
1877 anychanged = 1;
1878 }
1879 }
1880 }
1881 sched_unpin();
1882 vm_page_unlock_queues();
1883 if (anychanged)
1884 pmap_invalidate_all(pmap);
1885 PMAP_UNLOCK(pmap);
1886 }
1887
1888 /*
1889 * Insert the given physical page (p) at
1890 * the specified virtual address (v) in the
1891 * target physical map with the protection requested.
1892 *
1893 * If specified, the page will be wired down, meaning
1894 * that the related pte can not be reclaimed.
1895 *
1896 * NB: This is the only routine which MAY NOT lazy-evaluate
1897 * or lose information. That is, this routine must actually
1898 * insert this page into the given map NOW.
1899 */
1900 void
1901 pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
1902 boolean_t wired)
1903 {
1904 vm_paddr_t pa;
1905 register pt_entry_t *pte;
1906 vm_paddr_t opa;
1907 pt_entry_t origpte, newpte;
1908 vm_page_t mpte, om;
1909
1910 va &= PG_FRAME;
1911 #ifdef PMAP_DIAGNOSTIC
1912 if (va > VM_MAX_KERNEL_ADDRESS)
1913 panic("pmap_enter: toobig");
1914 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS))
1915 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va);
1916 #endif
1917
1918 mpte = NULL;
1919
1920 vm_page_lock_queues();
1921 PMAP_LOCK(pmap);
1922 sched_pin();
1923
1924 /*
1925 * In the case that a page table page is not
1926 * resident, we are creating it here.
1927 */
1928 if (va < VM_MAXUSER_ADDRESS) {
1929 mpte = pmap_allocpte(pmap, va, M_WAITOK);
1930 }
1931 #if 0 && defined(PMAP_DIAGNOSTIC)
1932 else {
1933 pd_entry_t *pdeaddr = pmap_pde(pmap, va);
1934 origpte = *pdeaddr;
1935 if ((origpte & PG_V) == 0) {
1936 panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n",
1937 pmap->pm_pdir[PTDPTDI], origpte, va);
1938 }
1939 }
1940 #endif
1941
1942 pte = pmap_pte_quick(pmap, va);
1943
1944 /*
1945 * Page Directory table entry not valid, we need a new PT page
1946 */
1947 if (pte == NULL) {
1948 panic("pmap_enter: invalid page directory pdir=%#jx, va=%#x\n",
1949 (uintmax_t)pmap->pm_pdir[PTDPTDI], va);
1950 }
1951
1952 pa = VM_PAGE_TO_PHYS(m);
1953 om = NULL;
1954 origpte = *pte;
1955 opa = origpte & PG_FRAME;
1956
1957 if (origpte & PG_PS) {
1958 /*
1959 * Yes, I know this will truncate upper address bits for PAE,
1960 * but I'm actually more interested in the lower bits
1961 */
1962 printf("pmap_enter: va %p, pte %p, origpte %p\n",
1963 (void *)va, (void *)pte, (void *)(uintptr_t)origpte);
1964 panic("pmap_enter: attempted pmap_enter on 4MB page");
1965 }
1966
1967 /*
1968 * Mapping has not changed, must be protection or wiring change.
1969 */
1970 if (origpte && (opa == pa)) {
1971 /*
1972 * Wiring change, just update stats. We don't worry about
1973 * wiring PT pages as they remain resident as long as there
1974 * are valid mappings in them. Hence, if a user page is wired,
1975 * the PT page will be also.
1976 */
1977 if (wired && ((origpte & PG_W) == 0))
1978 pmap->pm_stats.wired_count++;
1979 else if (!wired && (origpte & PG_W))
1980 pmap->pm_stats.wired_count--;
1981
1982 #if defined(PMAP_DIAGNOSTIC)
1983 if (pmap_nw_modified((pt_entry_t) origpte)) {
1984 printf(
1985 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n",
1986 va, origpte);
1987 }
1988 #endif
1989
1990 /*
1991 * Remove extra pte reference
1992 */
1993 if (mpte)
1994 mpte->wire_count--;
1995
1996 /*
1997 * We might be turning off write access to the page,
1998 * so we go ahead and sense modify status.
1999 */
2000 if (origpte & PG_MANAGED) {
2001 om = m;
2002 pa |= PG_MANAGED;
2003 }
2004 goto validate;
2005 }
2006 /*
2007 * Mapping has changed, invalidate old range and fall through to
2008 * handle validating new mapping.
2009 */
2010 if (opa) {
2011 int err;
2012 if (origpte & PG_W)
2013 pmap->pm_stats.wired_count--;
2014 if (origpte & PG_MANAGED) {
2015 om = PHYS_TO_VM_PAGE(opa);
2016 err = pmap_remove_entry(pmap, om, va);
2017 } else
2018 err = pmap_unuse_pt(pmap, va);
2019 if (err)
2020 panic("pmap_enter: pte vanished, va: 0x%x", va);
2021 } else
2022 pmap->pm_stats.resident_count++;
2023
2024 /*
2025 * Enter on the PV list if part of our managed memory. Note that we
2026 * raise IPL while manipulating pv_table since pmap_enter can be
2027 * called at interrupt time.
2028 */
2029 if (pmap_initialized &&
2030 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) {
2031 pmap_insert_entry(pmap, va, m);
2032 pa |= PG_MANAGED;
2033 }
2034
2035 /*
2036 * Increment counters
2037 */
2038 if (wired)
2039 pmap->pm_stats.wired_count++;
2040
2041 validate:
2042 /*
2043 * Now validate mapping with desired protection/wiring.
2044 */
2045 newpte = (pt_entry_t)(pa | PG_V);
2046 if ((prot & VM_PROT_WRITE) != 0)
2047 newpte |= PG_RW;
2048 if (wired)
2049 newpte |= PG_W;
2050 if (va < VM_MAXUSER_ADDRESS)
2051 newpte |= PG_U;
2052 if (pmap == kernel_pmap)
2053 newpte |= pgeflag;
2054
2055 /*
2056 * if the mapping or permission bits are different, we need
2057 * to update the pte.
2058 */
2059 if ((origpte & ~(PG_M|PG_A)) != newpte) {
2060 if (origpte & PG_MANAGED) {
2061 origpte = pte_load_store(pte, newpte | PG_A);
2062 if ((origpte & PG_M) && pmap_track_modified(va))
2063 vm_page_dirty(om);
2064 if (origpte & PG_A)
2065 vm_page_flag_set(om, PG_REFERENCED);
2066 } else
2067 pte_store(pte, newpte | PG_A);
2068 if (origpte) {
2069 pmap_invalidate_page(pmap, va);
2070 }
2071 }
2072 sched_unpin();
2073 vm_page_unlock_queues();
2074 PMAP_UNLOCK(pmap);
2075 }
2076
2077 /*
2078 * this code makes some *MAJOR* assumptions:
2079 * 1. Current pmap & pmap exists.
2080 * 2. Not wired.
2081 * 3. Read access.
2082 * 4. No page table pages.
2083 * 5. Tlbflush is deferred to calling procedure.
2084 * 6. Page IS managed.
2085 * but is *MUCH* faster than pmap_enter...
2086 */
2087
2088 vm_page_t
2089 pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte)
2090 {
2091 pt_entry_t *pte;
2092 vm_paddr_t pa;
2093
2094 vm_page_lock_queues();
2095 PMAP_LOCK(pmap);
2096
2097 /*
2098 * In the case that a page table page is not
2099 * resident, we are creating it here.
2100 */
2101 if (va < VM_MAXUSER_ADDRESS) {
2102 unsigned ptepindex;
2103 pd_entry_t ptepa;
2104
2105 /*
2106 * Calculate pagetable page index
2107 */
2108 ptepindex = va >> PDRSHIFT;
2109 if (mpte && (mpte->pindex == ptepindex)) {
2110 mpte->wire_count++;
2111 } else {
2112 retry:
2113 /*
2114 * Get the page directory entry
2115 */
2116 ptepa = pmap->pm_pdir[ptepindex];
2117
2118 /*
2119 * If the page table page is mapped, we just increment
2120 * the hold count, and activate it.
2121 */
2122 if (ptepa) {
2123 if (ptepa & PG_PS)
2124 panic("pmap_enter_quick: unexpected mapping into 4MB page");
2125 mpte = PHYS_TO_VM_PAGE(ptepa);
2126 mpte->wire_count++;
2127 } else {
2128 mpte = _pmap_allocpte(pmap, ptepindex,
2129 M_WAITOK);
2130 if (mpte == NULL)
2131 goto retry;
2132 }
2133 }
2134 } else {
2135 mpte = NULL;
2136 }
2137
2138 /*
2139 * This call to vtopte makes the assumption that we are
2140 * entering the page into the current pmap. In order to support
2141 * quick entry into any pmap, one would likely use pmap_pte_quick.
2142 * But that isn't as quick as vtopte.
2143 */
2144 pte = vtopte(va);
2145 if (*pte) {
2146 if (mpte != NULL) {
2147 pmap_unwire_pte_hold(pmap, mpte);
2148 mpte = NULL;
2149 }
2150 goto out;
2151 }
2152
2153 /*
2154 * Enter on the PV list if part of our managed memory. Note that we
2155 * raise IPL while manipulating pv_table since pmap_enter can be
2156 * called at interrupt time.
2157 */
2158 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0)
2159 pmap_insert_entry(pmap, va, m);
2160
2161 /*
2162 * Increment counters
2163 */
2164 pmap->pm_stats.resident_count++;
2165
2166 pa = VM_PAGE_TO_PHYS(m);
2167
2168 /*
2169 * Now validate mapping with RO protection
2170 */
2171 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED))
2172 pte_store(pte, pa | PG_V | PG_U);
2173 else
2174 pte_store(pte, pa | PG_V | PG_U | PG_MANAGED);
2175 out:
2176 vm_page_unlock_queues();
2177 PMAP_UNLOCK(pmap);
2178 return mpte;
2179 }
2180
2181 /*
2182 * Make a temporary mapping for a physical address. This is only intended
2183 * to be used for panic dumps.
2184 */
2185 void *
2186 pmap_kenter_temporary(vm_paddr_t pa, int i)
2187 {
2188 vm_offset_t va;
2189
2190 va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE);
2191 pmap_kenter(va, pa);
2192 #ifndef I386_CPU
2193 invlpg(va);
2194 #else
2195 invltlb();
2196 #endif
2197 return ((void *)crashdumpmap);
2198 }
2199
2200 /*
2201 * This code maps large physical mmap regions into the
2202 * processor address space. Note that some shortcuts
2203 * are taken, but the code works.
2204 */
2205 void
2206 pmap_object_init_pt(pmap_t pmap, vm_offset_t addr,
2207 vm_object_t object, vm_pindex_t pindex,
2208 vm_size_t size)
2209 {
2210 vm_page_t p;
2211
2212 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED);
2213 KASSERT(object->type == OBJT_DEVICE,
2214 ("pmap_object_init_pt: non-device object"));
2215 if (pseflag &&
2216 ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) {
2217 int i;
2218 vm_page_t m[1];
2219 unsigned int ptepindex;
2220 int npdes;
2221 pd_entry_t ptepa;
2222
2223 PMAP_LOCK(pmap);
2224 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)])
2225 goto out;
2226 PMAP_UNLOCK(pmap);
2227 retry:
2228 p = vm_page_lookup(object, pindex);
2229 if (p != NULL) {
2230 vm_page_lock_queues();
2231 if (vm_page_sleep_if_busy(p, FALSE, "init4p"))
2232 goto retry;
2233 } else {
2234 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL);
2235 if (p == NULL)
2236 return;
2237 m[0] = p;
2238
2239 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) {
2240 vm_page_lock_queues();
2241 vm_page_free(p);
2242 vm_page_unlock_queues();
2243 return;
2244 }
2245
2246 p = vm_page_lookup(object, pindex);
2247 vm_page_lock_queues();
2248 vm_page_wakeup(p);
2249 }
2250 vm_page_unlock_queues();
2251
2252 ptepa = VM_PAGE_TO_PHYS(p);
2253 if (ptepa & (NBPDR - 1))
2254 return;
2255
2256 p->valid = VM_PAGE_BITS_ALL;
2257
2258 PMAP_LOCK(pmap);
2259 pmap->pm_stats.resident_count += size >> PAGE_SHIFT;
2260 npdes = size >> PDRSHIFT;
2261 for(i = 0; i < npdes; i++) {
2262 pde_store(&pmap->pm_pdir[ptepindex],
2263 ptepa | PG_U | PG_RW | PG_V | PG_PS);
2264 ptepa += NBPDR;
2265 ptepindex += 1;
2266 }
2267 pmap_invalidate_all(pmap);
2268 out:
2269 PMAP_UNLOCK(pmap);
2270 }
2271 }
2272
2273 /*
2274 * Routine: pmap_change_wiring
2275 * Function: Change the wiring attribute for a map/virtual-address
2276 * pair.
2277 * In/out conditions:
2278 * The mapping must already exist in the pmap.
2279 */
2280 void
2281 pmap_change_wiring(pmap, va, wired)
2282 register pmap_t pmap;
2283 vm_offset_t va;
2284 boolean_t wired;
2285 {
2286 register pt_entry_t *pte;
2287
2288 PMAP_LOCK(pmap);
2289 pte = pmap_pte(pmap, va);
2290
2291 if (wired && !pmap_pte_w(pte))
2292 pmap->pm_stats.wired_count++;
2293 else if (!wired && pmap_pte_w(pte))
2294 pmap->pm_stats.wired_count--;
2295
2296 /*
2297 * Wiring is not a hardware characteristic so there is no need to
2298 * invalidate TLB.
2299 */
2300 pmap_pte_set_w(pte, wired);
2301 pmap_pte_release(pte);
2302 PMAP_UNLOCK(pmap);
2303 }
2304
2305
2306
2307 /*
2308 * Copy the range specified by src_addr/len
2309 * from the source map to the range dst_addr/len
2310 * in the destination map.
2311 *
2312 * This routine is only advisory and need not do anything.
2313 */
2314
2315 void
2316 pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len,
2317 vm_offset_t src_addr)
2318 {
2319 vm_offset_t addr;
2320 vm_offset_t end_addr = src_addr + len;
2321 vm_offset_t pdnxt;
2322 vm_page_t m;
2323
2324 if (dst_addr != src_addr)
2325 return;
2326
2327 if (!pmap_is_current(src_pmap))
2328 return;
2329
2330 vm_page_lock_queues();
2331 if (dst_pmap < src_pmap) {
2332 PMAP_LOCK(dst_pmap);
2333 PMAP_LOCK(src_pmap);
2334 } else {
2335 PMAP_LOCK(src_pmap);
2336 PMAP_LOCK(dst_pmap);
2337 }
2338 sched_pin();
2339 for (addr = src_addr; addr < end_addr; addr = pdnxt) {
2340 pt_entry_t *src_pte, *dst_pte;
2341 vm_page_t dstmpte, srcmpte;
2342 pd_entry_t srcptepaddr;
2343 unsigned ptepindex;
2344
2345 if (addr >= UPT_MIN_ADDRESS)
2346 panic("pmap_copy: invalid to pmap_copy page tables");
2347
2348 /*
2349 * Don't let optional prefaulting of pages make us go
2350 * way below the low water mark of free pages or way
2351 * above high water mark of used pv entries.
2352 */
2353 if (cnt.v_free_count < cnt.v_free_reserved ||
2354 pv_entry_count > pv_entry_high_water)
2355 break;
2356
2357 pdnxt = (addr + NBPDR) & ~PDRMASK;
2358 ptepindex = addr >> PDRSHIFT;
2359
2360 srcptepaddr = src_pmap->pm_pdir[ptepindex];
2361 if (srcptepaddr == 0)
2362 continue;
2363
2364 if (srcptepaddr & PG_PS) {
2365 if (dst_pmap->pm_pdir[ptepindex] == 0) {
2366 dst_pmap->pm_pdir[ptepindex] = srcptepaddr;
2367 dst_pmap->pm_stats.resident_count +=
2368 NBPDR / PAGE_SIZE;
2369 }
2370 continue;
2371 }
2372
2373 srcmpte = PHYS_TO_VM_PAGE(srcptepaddr);
2374 if (srcmpte->wire_count == 0)
2375 panic("pmap_copy: source page table page is unused");
2376
2377 if (pdnxt > end_addr)
2378 pdnxt = end_addr;
2379
2380 src_pte = vtopte(addr);
2381 while (addr < pdnxt) {
2382 pt_entry_t ptetemp;
2383 ptetemp = *src_pte;
2384 /*
2385 * we only virtual copy managed pages
2386 */
2387 if ((ptetemp & PG_MANAGED) != 0) {
2388 /*
2389 * We have to check after allocpte for the
2390 * pte still being around... allocpte can
2391 * block.
2392 */
2393 dstmpte = pmap_allocpte(dst_pmap, addr,
2394 M_NOWAIT);
2395 if (dstmpte == NULL)
2396 break;
2397 dst_pte = pmap_pte_quick(dst_pmap, addr);
2398 if (*dst_pte == 0) {
2399 /*
2400 * Clear the modified and
2401 * accessed (referenced) bits
2402 * during the copy.
2403 */
2404 m = PHYS_TO_VM_PAGE(ptetemp);
2405 *dst_pte = ptetemp & ~(PG_M | PG_A);
2406 dst_pmap->pm_stats.resident_count++;
2407 pmap_insert_entry(dst_pmap, addr, m);
2408 } else
2409 pmap_unwire_pte_hold(dst_pmap, dstmpte);
2410 if (dstmpte->wire_count >= srcmpte->wire_count)
2411 break;
2412 }
2413 addr += PAGE_SIZE;
2414 src_pte++;
2415 }
2416 }
2417 sched_unpin();
2418 vm_page_unlock_queues();
2419 PMAP_UNLOCK(src_pmap);
2420 PMAP_UNLOCK(dst_pmap);
2421 }
2422
2423 static __inline void
2424 pagezero(void *page)
2425 {
2426 #if defined(I686_CPU)
2427 if (cpu_class == CPUCLASS_686) {
2428 #if defined(CPU_ENABLE_SSE)
2429 if (cpu_feature & CPUID_SSE2)
2430 sse2_pagezero(page);
2431 else
2432 #endif
2433 i686_pagezero(page);
2434 } else
2435 #endif
2436 bzero(page, PAGE_SIZE);
2437 }
2438
2439 /*
2440 * pmap_zero_page zeros the specified hardware page by mapping
2441 * the page into KVM and using bzero to clear its contents.
2442 */
2443 void
2444 pmap_zero_page(vm_page_t m)
2445 {
2446 struct sysmaps *sysmaps;
2447
2448 sysmaps = &sysmaps_pcpu[PCPU_GET(cpuid)];
2449 mtx_lock(&sysmaps->lock);
2450 if (*sysmaps->CMAP2)
2451 panic("pmap_zero_page: CMAP2 busy");
2452 sched_pin();
2453 *sysmaps->CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(m) | PG_A | PG_M;
2454 invlcaddr(sysmaps->CADDR2);
2455 pagezero(sysmaps->CADDR2);
2456 *sysmaps->CMAP2 = 0;
2457 sched_unpin();
2458 mtx_unlock(&sysmaps->lock);
2459 }
2460
2461 /*
2462 * pmap_zero_page_area zeros the specified hardware page by mapping
2463 * the page into KVM and using bzero to clear its contents.
2464 *
2465 * off and size may not cover an area beyond a single hardware page.
2466 */
2467 void
2468 pmap_zero_page_area(vm_page_t m, int off, int size)
2469 {
2470 struct sysmaps *sysmaps;
2471
2472 sysmaps = &sysmaps_pcpu[PCPU_GET(cpuid)];
2473 mtx_lock(&sysmaps->lock);
2474 if (*sysmaps->CMAP2)
2475 panic("pmap_zero_page: CMAP2 busy");
2476 sched_pin();
2477 *sysmaps->CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(m) | PG_A | PG_M;
2478 invlcaddr(sysmaps->CADDR2);
2479 if (off == 0 && size == PAGE_SIZE)
2480 pagezero(sysmaps->CADDR2);
2481 else
2482 bzero((char *)sysmaps->CADDR2 + off, size);
2483 *sysmaps->CMAP2 = 0;
2484 sched_unpin();
2485 mtx_unlock(&sysmaps->lock);
2486 }
2487
2488 /*
2489 * pmap_zero_page_idle zeros the specified hardware page by mapping
2490 * the page into KVM and using bzero to clear its contents. This
2491 * is intended to be called from the vm_pagezero process only and
2492 * outside of Giant.
2493 */
2494 void
2495 pmap_zero_page_idle(vm_page_t m)
2496 {
2497
2498 if (*CMAP3)
2499 panic("pmap_zero_page: CMAP3 busy");
2500 sched_pin();
2501 *CMAP3 = PG_V | PG_RW | VM_PAGE_TO_PHYS(m) | PG_A | PG_M;
2502 invlcaddr(CADDR3);
2503 pagezero(CADDR3);
2504 *CMAP3 = 0;
2505 sched_unpin();
2506 }
2507
2508 /*
2509 * pmap_copy_page copies the specified (machine independent)
2510 * page by mapping the page into virtual memory and using
2511 * bcopy to copy the page, one machine dependent page at a
2512 * time.
2513 */
2514 void
2515 pmap_copy_page(vm_page_t src, vm_page_t dst)
2516 {
2517 struct sysmaps *sysmaps;
2518
2519 sysmaps = &sysmaps_pcpu[PCPU_GET(cpuid)];
2520 mtx_lock(&sysmaps->lock);
2521 if (*sysmaps->CMAP1)
2522 panic("pmap_copy_page: CMAP1 busy");
2523 if (*sysmaps->CMAP2)
2524 panic("pmap_copy_page: CMAP2 busy");
2525 sched_pin();
2526 #ifdef I386_CPU
2527 invltlb();
2528 #else
2529 invlpg((u_int)sysmaps->CADDR1);
2530 invlpg((u_int)sysmaps->CADDR2);
2531 #endif
2532 *sysmaps->CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A;
2533 *sysmaps->CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M;
2534 bcopy(sysmaps->CADDR1, sysmaps->CADDR2, PAGE_SIZE);
2535 *sysmaps->CMAP1 = 0;
2536 *sysmaps->CMAP2 = 0;
2537 sched_unpin();
2538 mtx_unlock(&sysmaps->lock);
2539 }
2540
2541 /*
2542 * Returns true if the pmap's pv is one of the first
2543 * 16 pvs linked to from this page. This count may
2544 * be changed upwards or downwards in the future; it
2545 * is only necessary that true be returned for a small
2546 * subset of pmaps for proper page aging.
2547 */
2548 boolean_t
2549 pmap_page_exists_quick(pmap, m)
2550 pmap_t pmap;
2551 vm_page_t m;
2552 {
2553 pv_entry_t pv;
2554 int loops = 0;
2555
2556 if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
2557 return FALSE;
2558
2559 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
2560 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
2561 if (pv->pv_pmap == pmap) {
2562 return TRUE;
2563 }
2564 loops++;
2565 if (loops >= 16)
2566 break;
2567 }
2568 return (FALSE);
2569 }
2570
2571 #define PMAP_REMOVE_PAGES_CURPROC_ONLY
2572 /*
2573 * Remove all pages from specified address space
2574 * this aids process exit speeds. Also, this code
2575 * is special cased for current process only, but
2576 * can have the more generic (and slightly slower)
2577 * mode enabled. This is much faster than pmap_remove
2578 * in the case of running down an entire address space.
2579 */
2580 void
2581 pmap_remove_pages(pmap, sva, eva)
2582 pmap_t pmap;
2583 vm_offset_t sva, eva;
2584 {
2585 pt_entry_t *pte, tpte;
2586 vm_page_t m;
2587 pv_entry_t pv, npv;
2588
2589 #ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY
2590 if (pmap != vmspace_pmap(curthread->td_proc->p_vmspace)) {
2591 printf("warning: pmap_remove_pages called with non-current pmap\n");
2592 return;
2593 }
2594 #endif
2595 vm_page_lock_queues();
2596 PMAP_LOCK(pmap);
2597 sched_pin();
2598 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) {
2599
2600 if (pv->pv_va >= eva || pv->pv_va < sva) {
2601 npv = TAILQ_NEXT(pv, pv_plist);
2602 continue;
2603 }
2604
2605 #ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY
2606 pte = vtopte(pv->pv_va);
2607 #else
2608 pte = pmap_pte_quick(pmap, pv->pv_va);
2609 #endif
2610 tpte = *pte;
2611
2612 if (tpte == 0) {
2613 printf("TPTE at %p IS ZERO @ VA %08x\n",
2614 pte, pv->pv_va);
2615 panic("bad pte");
2616 }
2617
2618 /*
2619 * We cannot remove wired pages from a process' mapping at this time
2620 */
2621 if (tpte & PG_W) {
2622 npv = TAILQ_NEXT(pv, pv_plist);
2623 continue;
2624 }
2625
2626 m = PHYS_TO_VM_PAGE(tpte);
2627 KASSERT(m->phys_addr == (tpte & PG_FRAME),
2628 ("vm_page_t %p phys_addr mismatch %016jx %016jx",
2629 m, (uintmax_t)m->phys_addr, (uintmax_t)tpte));
2630
2631 KASSERT(m < &vm_page_array[vm_page_array_size],
2632 ("pmap_remove_pages: bad tpte %#jx", (uintmax_t)tpte));
2633
2634 pmap->pm_stats.resident_count--;
2635
2636 pte_clear(pte);
2637
2638 /*
2639 * Update the vm_page_t clean and reference bits.
2640 */
2641 if (tpte & PG_M) {
2642 vm_page_dirty(m);
2643 }
2644
2645 npv = TAILQ_NEXT(pv, pv_plist);
2646 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist);
2647
2648 m->md.pv_list_count--;
2649 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
2650 if (TAILQ_EMPTY(&m->md.pv_list))
2651 vm_page_flag_clear(m, PG_WRITEABLE);
2652
2653 pmap_unuse_pt(pmap, pv->pv_va);
2654 free_pv_entry(pv);
2655 }
2656 sched_unpin();
2657 pmap_invalidate_all(pmap);
2658 PMAP_UNLOCK(pmap);
2659 vm_page_unlock_queues();
2660 }
2661
2662 /*
2663 * pmap_is_modified:
2664 *
2665 * Return whether or not the specified physical page was modified
2666 * in any physical maps.
2667 */
2668 boolean_t
2669 pmap_is_modified(vm_page_t m)
2670 {
2671 pv_entry_t pv;
2672 pt_entry_t *pte;
2673 boolean_t rv;
2674
2675 rv = FALSE;
2676 if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
2677 return (rv);
2678
2679 sched_pin();
2680 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
2681 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
2682 /*
2683 * if the bit being tested is the modified bit, then
2684 * mark clean_map and ptes as never
2685 * modified.
2686 */
2687 if (!pmap_track_modified(pv->pv_va))
2688 continue;
2689 #if defined(PMAP_DIAGNOSTIC)
2690 if (!pv->pv_pmap) {
2691 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va);
2692 continue;
2693 }
2694 #endif
2695 PMAP_LOCK(pv->pv_pmap);
2696 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
2697 rv = (*pte & PG_M) != 0;
2698 PMAP_UNLOCK(pv->pv_pmap);
2699 if (rv)
2700 break;
2701 }
2702 sched_unpin();
2703 return (rv);
2704 }
2705
2706 /*
2707 * pmap_is_prefaultable:
2708 *
2709 * Return whether or not the specified virtual address is elgible
2710 * for prefault.
2711 */
2712 boolean_t
2713 pmap_is_prefaultable(pmap_t pmap, vm_offset_t addr)
2714 {
2715 pt_entry_t *pte;
2716 boolean_t rv;
2717
2718 rv = FALSE;
2719 PMAP_LOCK(pmap);
2720 if (*pmap_pde(pmap, addr)) {
2721 pte = vtopte(addr);
2722 rv = *pte == 0;
2723 }
2724 PMAP_UNLOCK(pmap);
2725 return (rv);
2726 }
2727
2728 /*
2729 * Clear the given bit in each of the given page's ptes. The bit is
2730 * expressed as a 32-bit mask. Consequently, if the pte is 64 bits in
2731 * size, only a bit within the least significant 32 can be cleared.
2732 */
2733 static __inline void
2734 pmap_clear_ptes(vm_page_t m, int bit)
2735 {
2736 register pv_entry_t pv;
2737 pt_entry_t pbits, *pte;
2738
2739 if (!pmap_initialized || (m->flags & PG_FICTITIOUS) ||
2740 (bit == PG_RW && (m->flags & PG_WRITEABLE) == 0))
2741 return;
2742
2743 sched_pin();
2744 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
2745 /*
2746 * Loop over all current mappings setting/clearing as appropos If
2747 * setting RO do we need to clear the VAC?
2748 */
2749 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
2750 /*
2751 * don't write protect pager mappings
2752 */
2753 if (bit == PG_RW) {
2754 if (!pmap_track_modified(pv->pv_va))
2755 continue;
2756 }
2757
2758 #if defined(PMAP_DIAGNOSTIC)
2759 if (!pv->pv_pmap) {
2760 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va);
2761 continue;
2762 }
2763 #endif
2764
2765 PMAP_LOCK(pv->pv_pmap);
2766 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
2767 retry:
2768 pbits = *pte;
2769 if (pbits & bit) {
2770 if (bit == PG_RW) {
2771 /*
2772 * Regardless of whether a pte is 32 or 64 bits
2773 * in size, PG_RW and PG_M are among the least
2774 * significant 32 bits.
2775 */
2776 if (!atomic_cmpset_int((u_int *)pte, pbits,
2777 pbits & ~(PG_RW | PG_M)))
2778 goto retry;
2779 if (pbits & PG_M) {
2780 vm_page_dirty(m);
2781 }
2782 } else {
2783 atomic_clear_int((u_int *)pte, bit);
2784 }
2785 pmap_invalidate_page(pv->pv_pmap, pv->pv_va);
2786 }
2787 PMAP_UNLOCK(pv->pv_pmap);
2788 }
2789 if (bit == PG_RW)
2790 vm_page_flag_clear(m, PG_WRITEABLE);
2791 sched_unpin();
2792 }
2793
2794 /*
2795 * pmap_page_protect:
2796 *
2797 * Lower the permission for all mappings to a given page.
2798 */
2799 void
2800 pmap_page_protect(vm_page_t m, vm_prot_t prot)
2801 {
2802 if ((prot & VM_PROT_WRITE) == 0) {
2803 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) {
2804 pmap_clear_ptes(m, PG_RW);
2805 } else {
2806 pmap_remove_all(m);
2807 }
2808 }
2809 }
2810
2811 /*
2812 * pmap_ts_referenced:
2813 *
2814 * Return a count of reference bits for a page, clearing those bits.
2815 * It is not necessary for every reference bit to be cleared, but it
2816 * is necessary that 0 only be returned when there are truly no
2817 * reference bits set.
2818 *
2819 * XXX: The exact number of bits to check and clear is a matter that
2820 * should be tested and standardized at some point in the future for
2821 * optimal aging of shared pages.
2822 */
2823 int
2824 pmap_ts_referenced(vm_page_t m)
2825 {
2826 register pv_entry_t pv, pvf, pvn;
2827 pt_entry_t *pte;
2828 pt_entry_t v;
2829 int rtval = 0;
2830
2831 if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
2832 return (rtval);
2833
2834 sched_pin();
2835 mtx_assert(&vm_page_queue_mtx, MA_OWNED);
2836 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
2837
2838 pvf = pv;
2839
2840 do {
2841 pvn = TAILQ_NEXT(pv, pv_list);
2842
2843 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
2844
2845 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
2846
2847 if (!pmap_track_modified(pv->pv_va))
2848 continue;
2849
2850 PMAP_LOCK(pv->pv_pmap);
2851 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
2852
2853 if (pte && ((v = pte_load(pte)) & PG_A) != 0) {
2854 atomic_clear_int((u_int *)pte, PG_A);
2855 pmap_invalidate_page(pv->pv_pmap, pv->pv_va);
2856
2857 rtval++;
2858 if (rtval > 4) {
2859 PMAP_UNLOCK(pv->pv_pmap);
2860 break;
2861 }
2862 }
2863 PMAP_UNLOCK(pv->pv_pmap);
2864 } while ((pv = pvn) != NULL && pv != pvf);
2865 }
2866 sched_unpin();
2867
2868 return (rtval);
2869 }
2870
2871 /*
2872 * Clear the modify bits on the specified physical page.
2873 */
2874 void
2875 pmap_clear_modify(vm_page_t m)
2876 {
2877 pmap_clear_ptes(m, PG_M);
2878 }
2879
2880 /*
2881 * pmap_clear_reference:
2882 *
2883 * Clear the reference bit on the specified physical page.
2884 */
2885 void
2886 pmap_clear_reference(vm_page_t m)
2887 {
2888 pmap_clear_ptes(m, PG_A);
2889 }
2890
2891 /*
2892 * Miscellaneous support routines follow
2893 */
2894
2895 /*
2896 * Map a set of physical memory pages into the kernel virtual
2897 * address space. Return a pointer to where it is mapped. This
2898 * routine is intended to be used for mapping device memory,
2899 * NOT real memory.
2900 */
2901 void *
2902 pmap_mapdev(pa, size)
2903 vm_paddr_t pa;
2904 vm_size_t size;
2905 {
2906 vm_offset_t va, tmpva, offset;
2907
2908 offset = pa & PAGE_MASK;
2909 size = roundup(offset + size, PAGE_SIZE);
2910 pa = pa & PG_FRAME;
2911
2912 if (pa < KERNLOAD && pa + size <= KERNLOAD)
2913 va = KERNBASE + pa;
2914 else
2915 va = kmem_alloc_nofault(kernel_map, size);
2916 if (!va)
2917 panic("pmap_mapdev: Couldn't alloc kernel virtual memory");
2918
2919 for (tmpva = va; size > 0; ) {
2920 pmap_kenter(tmpva, pa);
2921 size -= PAGE_SIZE;
2922 tmpva += PAGE_SIZE;
2923 pa += PAGE_SIZE;
2924 }
2925 pmap_invalidate_range(kernel_pmap, va, tmpva);
2926 return ((void *)(va + offset));
2927 }
2928
2929 void
2930 pmap_unmapdev(va, size)
2931 vm_offset_t va;
2932 vm_size_t size;
2933 {
2934 vm_offset_t base, offset, tmpva;
2935
2936 if (va >= KERNBASE && va + size <= KERNBASE + KERNLOAD)
2937 return;
2938 base = va & PG_FRAME;
2939 offset = va & PAGE_MASK;
2940 size = roundup(offset + size, PAGE_SIZE);
2941 for (tmpva = base; tmpva < (base + size); tmpva += PAGE_SIZE)
2942 pmap_kremove(tmpva);
2943 pmap_invalidate_range(kernel_pmap, va, tmpva);
2944 kmem_free(kernel_map, base, size);
2945 }
2946
2947 /*
2948 * perform the pmap work for mincore
2949 */
2950 int
2951 pmap_mincore(pmap, addr)
2952 pmap_t pmap;
2953 vm_offset_t addr;
2954 {
2955 pt_entry_t *ptep, pte;
2956 vm_page_t m;
2957 int val = 0;
2958
2959 PMAP_LOCK(pmap);
2960 ptep = pmap_pte(pmap, addr);
2961 pte = (ptep != NULL) ? *ptep : 0;
2962 pmap_pte_release(ptep);
2963 PMAP_UNLOCK(pmap);
2964
2965 if (pte != 0) {
2966 vm_paddr_t pa;
2967
2968 val = MINCORE_INCORE;
2969 if ((pte & PG_MANAGED) == 0)
2970 return val;
2971
2972 pa = pte & PG_FRAME;
2973
2974 m = PHYS_TO_VM_PAGE(pa);
2975
2976 /*
2977 * Modified by us
2978 */
2979 if (pte & PG_M)
2980 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER;
2981 else {
2982 /*
2983 * Modified by someone else
2984 */
2985 vm_page_lock_queues();
2986 if (m->dirty || pmap_is_modified(m))
2987 val |= MINCORE_MODIFIED_OTHER;
2988 vm_page_unlock_queues();
2989 }
2990 /*
2991 * Referenced by us
2992 */
2993 if (pte & PG_A)
2994 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER;
2995 else {
2996 /*
2997 * Referenced by someone else
2998 */
2999 vm_page_lock_queues();
3000 if ((m->flags & PG_REFERENCED) ||
3001 pmap_ts_referenced(m)) {
3002 val |= MINCORE_REFERENCED_OTHER;
3003 vm_page_flag_set(m, PG_REFERENCED);
3004 }
3005 vm_page_unlock_queues();
3006 }
3007 }
3008 return val;
3009 }
3010
3011 void
3012 pmap_activate(struct thread *td)
3013 {
3014 struct proc *p = td->td_proc;
3015 pmap_t pmap, oldpmap;
3016 u_int32_t cr3;
3017
3018 critical_enter();
3019 pmap = vmspace_pmap(td->td_proc->p_vmspace);
3020 oldpmap = PCPU_GET(curpmap);
3021 #if defined(SMP)
3022 atomic_clear_int(&oldpmap->pm_active, PCPU_GET(cpumask));
3023 atomic_set_int(&pmap->pm_active, PCPU_GET(cpumask));
3024 #else
3025 oldpmap->pm_active &= ~1;
3026 pmap->pm_active |= 1;
3027 #endif
3028 #ifdef PAE
3029 cr3 = vtophys(pmap->pm_pdpt);
3030 #else
3031 cr3 = vtophys(pmap->pm_pdir);
3032 #endif
3033 /* XXXKSE this is wrong.
3034 * pmap_activate is for the current thread on the current cpu
3035 */
3036 if (p->p_flag & P_SA) {
3037 /* Make sure all other cr3 entries are updated. */
3038 /* what if they are running? XXXKSE (maybe abort them) */
3039 FOREACH_THREAD_IN_PROC(p, td) {
3040 td->td_pcb->pcb_cr3 = cr3;
3041 }
3042 } else {
3043 td->td_pcb->pcb_cr3 = cr3;
3044 }
3045 load_cr3(cr3);
3046 PCPU_SET(curpmap, pmap);
3047 critical_exit();
3048 }
3049
3050 vm_offset_t
3051 pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size)
3052 {
3053
3054 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) {
3055 return addr;
3056 }
3057
3058 addr = (addr + PDRMASK) & ~PDRMASK;
3059 return addr;
3060 }
3061
3062
3063 #if defined(PMAP_DEBUG)
3064 pmap_pid_dump(int pid)
3065 {
3066 pmap_t pmap;
3067 struct proc *p;
3068 int npte = 0;
3069 int index;
3070
3071 sx_slock(&allproc_lock);
3072 LIST_FOREACH(p, &allproc, p_list) {
3073 if (p->p_pid != pid)
3074 continue;
3075
3076 if (p->p_vmspace) {
3077 int i,j;
3078 index = 0;
3079 pmap = vmspace_pmap(p->p_vmspace);
3080 for (i = 0; i < NPDEPTD; i++) {
3081 pd_entry_t *pde;
3082 pt_entry_t *pte;
3083 vm_offset_t base = i << PDRSHIFT;
3084
3085 pde = &pmap->pm_pdir[i];
3086 if (pde && pmap_pde_v(pde)) {
3087 for (j = 0; j < NPTEPG; j++) {
3088 vm_offset_t va = base + (j << PAGE_SHIFT);
3089 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) {
3090 if (index) {
3091 index = 0;
3092 printf("\n");
3093 }
3094 sx_sunlock(&allproc_lock);
3095 return npte;
3096 }
3097 pte = pmap_pte(pmap, va);
3098 if (pte && pmap_pte_v(pte)) {
3099 pt_entry_t pa;
3100 vm_page_t m;
3101 pa = *pte;
3102 m = PHYS_TO_VM_PAGE(pa);
3103 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x",
3104 va, pa, m->hold_count, m->wire_count, m->flags);
3105 npte++;
3106 index++;
3107 if (index >= 2) {
3108 index = 0;
3109 printf("\n");
3110 } else {
3111 printf(" ");
3112 }
3113 }
3114 }
3115 }
3116 }
3117 }
3118 }
3119 sx_sunlock(&allproc_lock);
3120 return npte;
3121 }
3122 #endif
3123
3124 #if defined(DEBUG)
3125
3126 static void pads(pmap_t pm);
3127 void pmap_pvdump(vm_offset_t pa);
3128
3129 /* print address space of pmap*/
3130 static void
3131 pads(pm)
3132 pmap_t pm;
3133 {
3134 int i, j;
3135 vm_paddr_t va;
3136 pt_entry_t *ptep;
3137
3138 if (pm == kernel_pmap)
3139 return;
3140 for (i = 0; i < NPDEPTD; i++)
3141 if (pm->pm_pdir[i])
3142 for (j = 0; j < NPTEPG; j++) {
3143 va = (i << PDRSHIFT) + (j << PAGE_SHIFT);
3144 if (pm == kernel_pmap && va < KERNBASE)
3145 continue;
3146 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS)
3147 continue;
3148 ptep = pmap_pte(pm, va);
3149 if (pmap_pte_v(ptep))
3150 printf("%x:%x ", va, *ptep);
3151 };
3152
3153 }
3154
3155 void
3156 pmap_pvdump(pa)
3157 vm_paddr_t pa;
3158 {
3159 pv_entry_t pv;
3160 vm_page_t m;
3161
3162 printf("pa %x", pa);
3163 m = PHYS_TO_VM_PAGE(pa);
3164 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
3165 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va);
3166 pads(pv->pv_pmap);
3167 }
3168 printf(" ");
3169 }
3170 #endif
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