4 * Copyright (c) 1991 Regents of the University of California.
5 * Copyright (c) 1994 John S. Dyson
6 * Copyright (c) 1994 David Greenman
7 * Copyright (c) 2003 Peter Wemm
8 * Copyright (c) 2005-2008 Alan L. Cox <alc@cs.rice.edu>
9 * Copyright (c) 2008, 2009 The DragonFly Project.
10 * Copyright (c) 2008, 2009 Jordan Gordeev.
11 * All rights reserved.
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.
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions
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.
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
45 * from: @(#)pmap.c 7.7 (Berkeley) 5/12/91
46 * $FreeBSD: src/sys/i386/i386/pmap.c,v 1.250.2.18 2002/03/06 22:48:53 silby Exp $
50 * Manages physical address maps.
56 #include "opt_msgbuf.h"
58 #include <sys/param.h>
59 #include <sys/systm.h>
60 #include <sys/kernel.h>
62 #include <sys/msgbuf.h>
63 #include <sys/vmmeter.h>
65 #include <sys/vmspace.h>
68 #include <vm/vm_param.h>
69 #include <sys/sysctl.h>
71 #include <vm/vm_kern.h>
72 #include <vm/vm_page.h>
73 #include <vm/vm_map.h>
74 #include <vm/vm_object.h>
75 #include <vm/vm_extern.h>
76 #include <vm/vm_pageout.h>
77 #include <vm/vm_pager.h>
78 #include <vm/vm_zone.h>
81 #include <sys/thread2.h>
82 #include <sys/sysref2.h>
83 #include <sys/spinlock2.h>
85 #include <machine/cputypes.h>
86 #include <machine/md_var.h>
87 #include <machine/specialreg.h>
88 #include <machine/smp.h>
89 #include <machine/globaldata.h>
90 #include <machine/pmap.h>
91 #include <machine/pmap_inval.h>
99 #define PMAP_KEEP_PDIRS
100 #ifndef PMAP_SHPGPERPROC
101 #define PMAP_SHPGPERPROC 200
104 #if defined(DIAGNOSTIC)
105 #define PMAP_DIAGNOSTIC
110 #if !defined(PMAP_DIAGNOSTIC)
111 #define PMAP_INLINE __inline
117 * Get PDEs and PTEs for user/kernel address space
119 static pd_entry_t *pmap_pde(pmap_t pmap, vm_offset_t va);
120 #define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT])
122 #define pmap_pde_v(pte) ((*(pd_entry_t *)pte & VPTE_V) != 0)
123 #define pmap_pte_w(pte) ((*(pt_entry_t *)pte & VPTE_WIRED) != 0)
124 #define pmap_pte_m(pte) ((*(pt_entry_t *)pte & VPTE_M) != 0)
125 #define pmap_pte_u(pte) ((*(pt_entry_t *)pte & VPTE_A) != 0)
126 #define pmap_pte_v(pte) ((*(pt_entry_t *)pte & VPTE_V) != 0)
129 * Given a map and a machine independent protection code,
130 * convert to a vax protection code.
132 #define pte_prot(m, p) \
133 (protection_codes[p & (VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE)])
134 static int protection_codes[8];
136 struct pmap kernel_pmap;
137 static TAILQ_HEAD(,pmap) pmap_list = TAILQ_HEAD_INITIALIZER(pmap_list);
139 static boolean_t pmap_initialized = FALSE; /* Has pmap_init completed? */
141 static vm_object_t kptobj;
145 static uint64_t KPDphys; /* phys addr of kernel level 2 */
146 uint64_t KPDPphys; /* phys addr of kernel level 3 */
147 uint64_t KPML4phys; /* phys addr of kernel level 4 */
151 * Data for the pv entry allocation mechanism
153 static vm_zone_t pvzone;
154 static struct vm_zone pvzone_store;
155 static struct vm_object pvzone_obj;
156 static int pv_entry_count=0, pv_entry_max=0, pv_entry_high_water=0;
157 static int pmap_pagedaemon_waken = 0;
158 static struct pv_entry *pvinit;
161 * All those kernel PT submaps that BSD is so fond of
163 pt_entry_t *CMAP1 = 0, *ptmmap;
165 static pt_entry_t *msgbufmap;
169 static PMAP_INLINE void free_pv_entry (pv_entry_t pv);
170 static pv_entry_t get_pv_entry (void);
171 static void i386_protection_init (void);
172 static __inline void pmap_clearbit (vm_page_t m, int bit);
174 static void pmap_remove_all (vm_page_t m);
175 static int pmap_remove_pte (struct pmap *pmap, pt_entry_t *ptq,
177 static void pmap_remove_page (struct pmap *pmap, vm_offset_t va);
178 static int pmap_remove_entry (struct pmap *pmap, vm_page_t m,
180 static boolean_t pmap_testbit (vm_page_t m, int bit);
181 static void pmap_insert_entry (pmap_t pmap, vm_offset_t va,
182 vm_page_t mpte, vm_page_t m);
184 static vm_page_t pmap_allocpte (pmap_t pmap, vm_offset_t va);
186 static int pmap_release_free_page (pmap_t pmap, vm_page_t p);
187 static vm_page_t _pmap_allocpte (pmap_t pmap, vm_pindex_t ptepindex);
189 static pt_entry_t * pmap_pte_quick (pmap_t pmap, vm_offset_t va);
191 static vm_page_t pmap_page_lookup (vm_object_t object, vm_pindex_t pindex);
192 static int pmap_unuse_pt (pmap_t, vm_offset_t, vm_page_t);
197 * Super fast pmap_pte routine best used when scanning the pv lists.
198 * This eliminates many course-grained invltlb calls. Note that many of
199 * the pv list scans are across different pmaps and it is very wasteful
200 * to do an entire invltlb when checking a single mapping.
202 * Should only be called while in a critical section.
205 static __inline pt_entry_t *pmap_pte(pmap_t pmap, vm_offset_t va);
208 pmap_pte_quick(pmap_t pmap, vm_offset_t va)
210 return pmap_pte(pmap, va);
214 /* Return a non-clipped PD index for a given VA */
215 static __inline vm_pindex_t
216 pmap_pde_pindex(vm_offset_t va)
218 return va >> PDRSHIFT;
221 /* Return various clipped indexes for a given VA */
222 static __inline vm_pindex_t
223 pmap_pte_index(vm_offset_t va)
226 return ((va >> PAGE_SHIFT) & ((1ul << NPTEPGSHIFT) - 1));
229 static __inline vm_pindex_t
230 pmap_pde_index(vm_offset_t va)
233 return ((va >> PDRSHIFT) & ((1ul << NPDEPGSHIFT) - 1));
236 static __inline vm_pindex_t
237 pmap_pdpe_index(vm_offset_t va)
240 return ((va >> PDPSHIFT) & ((1ul << NPDPEPGSHIFT) - 1));
243 static __inline vm_pindex_t
244 pmap_pml4e_index(vm_offset_t va)
247 return ((va >> PML4SHIFT) & ((1ul << NPML4EPGSHIFT) - 1));
250 /* Return a pointer to the PML4 slot that corresponds to a VA */
251 static __inline pml4_entry_t *
252 pmap_pml4e(pmap_t pmap, vm_offset_t va)
255 return (&pmap->pm_pml4[pmap_pml4e_index(va)]);
258 /* Return a pointer to the PDP slot that corresponds to a VA */
259 static __inline pdp_entry_t *
260 pmap_pml4e_to_pdpe(pml4_entry_t *pml4e, vm_offset_t va)
264 pdpe = (pdp_entry_t *)PHYS_TO_DMAP(*pml4e & VPTE_FRAME);
265 return (&pdpe[pmap_pdpe_index(va)]);
268 /* Return a pointer to the PDP slot that corresponds to a VA */
269 static __inline pdp_entry_t *
270 pmap_pdpe(pmap_t pmap, vm_offset_t va)
274 pml4e = pmap_pml4e(pmap, va);
275 if ((*pml4e & VPTE_V) == 0)
277 return (pmap_pml4e_to_pdpe(pml4e, va));
280 /* Return a pointer to the PD slot that corresponds to a VA */
281 static __inline pd_entry_t *
282 pmap_pdpe_to_pde(pdp_entry_t *pdpe, vm_offset_t va)
286 pde = (pd_entry_t *)PHYS_TO_DMAP(*pdpe & VPTE_FRAME);
287 return (&pde[pmap_pde_index(va)]);
290 /* Return a pointer to the PD slot that corresponds to a VA */
291 static __inline pd_entry_t *
292 pmap_pde(pmap_t pmap, vm_offset_t va)
296 pdpe = pmap_pdpe(pmap, va);
297 if (pdpe == NULL || (*pdpe & VPTE_V) == 0)
299 return (pmap_pdpe_to_pde(pdpe, va));
302 /* Return a pointer to the PT slot that corresponds to a VA */
303 static __inline pt_entry_t *
304 pmap_pde_to_pte(pd_entry_t *pde, vm_offset_t va)
308 pte = (pt_entry_t *)PHYS_TO_DMAP(*pde & VPTE_FRAME);
309 return (&pte[pmap_pte_index(va)]);
312 /* Return a pointer to the PT slot that corresponds to a VA */
313 static __inline pt_entry_t *
314 pmap_pte(pmap_t pmap, vm_offset_t va)
318 pde = pmap_pde(pmap, va);
319 if (pde == NULL || (*pde & VPTE_V) == 0)
321 if ((*pde & VPTE_PS) != 0) /* compat with i386 pmap_pte() */
322 return ((pt_entry_t *)pde);
323 return (pmap_pde_to_pte(pde, va));
328 PMAP_INLINE pt_entry_t *
329 vtopte(vm_offset_t va)
331 uint64_t mask = ((1ul << (NPTEPGSHIFT + NPDEPGSHIFT +
332 NPDPEPGSHIFT + NPML4EPGSHIFT)) - 1);
334 return (PTmap + ((va >> PAGE_SHIFT) & mask));
337 static __inline pd_entry_t *
338 vtopde(vm_offset_t va)
340 uint64_t mask = ((1ul << (NPDEPGSHIFT + NPDPEPGSHIFT +
341 NPML4EPGSHIFT)) - 1);
343 return (PDmap + ((va >> PDRSHIFT) & mask));
346 static PMAP_INLINE pt_entry_t *
347 vtopte(vm_offset_t va)
350 x = pmap_pte(&kernel_pmap, va);
355 static __inline pd_entry_t *
356 vtopde(vm_offset_t va)
359 x = pmap_pde(&kernel_pmap, va);
366 allocpages(vm_paddr_t *firstaddr, int n)
372 bzero((void *)ret, n * PAGE_SIZE);
374 *firstaddr += n * PAGE_SIZE;
379 create_pagetables(vm_paddr_t *firstaddr, int64_t ptov_offset)
382 pml4_entry_t *KPML4virt;
383 pdp_entry_t *KPDPvirt;
386 int kpml4i = pmap_pml4e_index(ptov_offset);
387 int kpdpi = pmap_pdpe_index(ptov_offset);
390 * Calculate NKPT - number of kernel page tables. We have to
391 * accomodoate prealloction of the vm_page_array, dump bitmap,
392 * MSGBUF_SIZE, and other stuff. Be generous.
394 * Maxmem is in pages.
396 nkpt = (Maxmem * (sizeof(struct vm_page) * 2) + MSGBUF_SIZE) / NBPDR;
401 KPML4phys = allocpages(firstaddr, 1);
402 KPDPphys = allocpages(firstaddr, NKPML4E);
403 KPDphys = allocpages(firstaddr, NKPDPE);
404 KPTphys = allocpages(firstaddr, nkpt);
406 KPML4virt = (pml4_entry_t *)PHYS_TO_DMAP(KPML4phys);
407 KPDPvirt = (pdp_entry_t *)PHYS_TO_DMAP(KPDPphys);
408 KPDvirt = (pd_entry_t *)PHYS_TO_DMAP(KPDphys);
409 KPTvirt = (pt_entry_t *)PHYS_TO_DMAP(KPTphys);
411 bzero(KPML4virt, 1 * PAGE_SIZE);
412 bzero(KPDPvirt, NKPML4E * PAGE_SIZE);
413 bzero(KPDvirt, NKPDPE * PAGE_SIZE);
414 bzero(KPTvirt, nkpt * PAGE_SIZE);
416 /* Now map the page tables at their location within PTmap */
417 for (i = 0; i < nkpt; i++) {
418 KPDvirt[i] = KPTphys + (i << PAGE_SHIFT);
419 KPDvirt[i] |= VPTE_R | VPTE_W | VPTE_V;
422 /* And connect up the PD to the PDP */
423 for (i = 0; i < NKPDPE; i++) {
424 KPDPvirt[i + kpdpi] = KPDphys + (i << PAGE_SHIFT);
425 KPDPvirt[i + kpdpi] |= VPTE_R | VPTE_W | VPTE_V;
428 /* And recursively map PML4 to itself in order to get PTmap */
429 KPML4virt[PML4PML4I] = KPML4phys;
430 KPML4virt[PML4PML4I] |= VPTE_R | VPTE_W | VPTE_V;
432 /* Connect the KVA slot up to the PML4 */
433 KPML4virt[kpml4i] = KPDPphys;
434 KPML4virt[kpml4i] |= VPTE_R | VPTE_W | VPTE_V;
438 * Bootstrap the system enough to run with virtual memory.
440 * On the i386 this is called after mapping has already been enabled
441 * and just syncs the pmap module with what has already been done.
442 * [We can't call it easily with mapping off since the kernel is not
443 * mapped with PA == VA, hence we would have to relocate every address
444 * from the linked base (virtual) address "KERNBASE" to the actual
445 * (physical) address starting relative to 0]
448 pmap_bootstrap(vm_paddr_t *firstaddr, int64_t ptov_offset)
454 * Create an initial set of page tables to run the kernel in.
456 create_pagetables(firstaddr, ptov_offset);
458 virtual_start = KvaStart + *firstaddr;
459 virtual_end = KvaEnd;
462 * Initialize protection array.
464 i386_protection_init();
467 * The kernel's pmap is statically allocated so we don't have to use
468 * pmap_create, which is unlikely to work correctly at this part of
469 * the boot sequence (XXX and which no longer exists).
471 * The kernel_pmap's pm_pteobj is used only for locking and not
474 kernel_pmap.pm_pml4 = (pml4_entry_t *)PHYS_TO_DMAP(KPML4phys);
475 kernel_pmap.pm_count = 1;
476 kernel_pmap.pm_active = (cpumask_t)-1; /* don't allow deactivation */
477 kernel_pmap.pm_pteobj = &kernel_object;
478 TAILQ_INIT(&kernel_pmap.pm_pvlist);
479 TAILQ_INIT(&kernel_pmap.pm_pvlist_free);
480 lwkt_token_init(&kernel_pmap.pm_token, "kpmap_tok");
481 spin_init(&kernel_pmap.pm_spin);
484 * Reserve some special page table entries/VA space for temporary
487 #define SYSMAP(c, p, v, n) \
488 v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n);
491 pte = pmap_pte(&kernel_pmap, va);
494 * CMAP1/CMAP2 are used for zeroing and copying pages.
496 SYSMAP(caddr_t, CMAP1, CADDR1, 1)
502 SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS);
506 * ptvmmap is used for reading arbitrary physical pages via
509 SYSMAP(caddr_t, ptmmap, ptvmmap, 1)
512 * msgbufp is used to map the system message buffer.
513 * XXX msgbufmap is not used.
515 SYSMAP(struct msgbuf *, msgbufmap, msgbufp,
516 atop(round_page(MSGBUF_SIZE)))
526 * Initialize the pmap module.
527 * Called by vm_init, to initialize any structures that the pmap
528 * system needs to map virtual memory.
529 * pmap_init has been enhanced to support in a fairly consistant
530 * way, discontiguous physical memory.
539 * object for kernel page table pages
541 /* JG I think the number can be arbitrary */
542 kptobj = vm_object_allocate(OBJT_DEFAULT, 5);
545 * Allocate memory for random pmap data structures. Includes the
549 for(i = 0; i < vm_page_array_size; i++) {
552 m = &vm_page_array[i];
553 TAILQ_INIT(&m->md.pv_list);
554 m->md.pv_list_count = 0;
558 * init the pv free list
560 initial_pvs = vm_page_array_size;
561 if (initial_pvs < MINPV)
563 pvzone = &pvzone_store;
564 pvinit = (struct pv_entry *) kmem_alloc(&kernel_map,
565 initial_pvs * sizeof (struct pv_entry));
566 zbootinit(pvzone, "PV ENTRY", sizeof (struct pv_entry), pvinit,
570 * Now it is safe to enable pv_table recording.
572 pmap_initialized = TRUE;
576 * Initialize the address space (zone) for the pv_entries. Set a
577 * high water mark so that the system can recover from excessive
578 * numbers of pv entries.
583 int shpgperproc = PMAP_SHPGPERPROC;
585 TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc);
586 pv_entry_max = shpgperproc * maxproc + vm_page_array_size;
587 TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max);
588 pv_entry_high_water = 9 * (pv_entry_max / 10);
589 zinitna(pvzone, &pvzone_obj, NULL, 0, pv_entry_max, ZONE_INTERRUPT, 1);
593 /***************************************************
594 * Low level helper routines.....
595 ***************************************************/
598 * The modification bit is not tracked for any pages in this range. XXX
599 * such pages in this maps should always use pmap_k*() functions and not
602 * XXX User and kernel address spaces are independant for virtual kernels,
603 * this function only applies to the kernel pmap.
606 pmap_track_modified(pmap_t pmap, vm_offset_t va)
608 if (pmap != &kernel_pmap)
610 if ((va < clean_sva) || (va >= clean_eva))
617 * Extract the physical page address associated with the map/VA pair.
622 pmap_extract(pmap_t pmap, vm_offset_t va)
626 pd_entry_t pde, *pdep;
628 lwkt_gettoken(&vm_token);
630 pdep = pmap_pde(pmap, va);
634 if ((pde & VPTE_PS) != 0) {
636 rtval = (pde & PG_PS_FRAME) | (va & PDRMASK);
638 pte = pmap_pde_to_pte(pdep, va);
639 rtval = (*pte & VPTE_FRAME) | (va & PAGE_MASK);
643 lwkt_reltoken(&vm_token);
648 * Routine: pmap_kextract
650 * Extract the physical page address associated
651 * kernel virtual address.
654 pmap_kextract(vm_offset_t va)
659 KKASSERT(va >= KvaStart && va < KvaEnd);
662 * The DMAP region is not included in [KvaStart, KvaEnd)
665 if (va >= DMAP_MIN_ADDRESS && va < DMAP_MAX_ADDRESS) {
666 pa = DMAP_TO_PHYS(va);
672 pa = (pde & PG_PS_FRAME) | (va & PDRMASK);
675 * Beware of a concurrent promotion that changes the
676 * PDE at this point! For example, vtopte() must not
677 * be used to access the PTE because it would use the
678 * new PDE. It is, however, safe to use the old PDE
679 * because the page table page is preserved by the
682 pa = *pmap_pde_to_pte(&pde, va);
683 pa = (pa & VPTE_FRAME) | (va & PAGE_MASK);
691 /***************************************************
692 * Low level mapping routines.....
693 ***************************************************/
696 * Enter a mapping into kernel_pmap. Mappings created in this fashion
697 * are not managed. Mappings must be immediately accessible on all cpus.
699 * Call pmap_inval_pte() to invalidate the virtual pte and clean out the
700 * real pmap and handle related races before storing the new vpte.
703 pmap_kenter(vm_offset_t va, vm_paddr_t pa)
708 KKASSERT(va >= KvaStart && va < KvaEnd);
709 npte = pa | VPTE_R | VPTE_W | VPTE_V;
712 pmap_inval_pte(pte, &kernel_pmap, va);
717 * Enter an unmanaged KVA mapping for the private use of the current
718 * cpu only. pmap_kenter_sync() may be called to make the mapping usable
721 * It is illegal for the mapping to be accessed by other cpus unleess
722 * pmap_kenter_sync*() is called.
725 pmap_kenter_quick(vm_offset_t va, vm_paddr_t pa)
730 KKASSERT(va >= KvaStart && va < KvaEnd);
732 npte = (vpte_t)pa | VPTE_R | VPTE_W | VPTE_V;
735 pmap_inval_pte_quick(pte, &kernel_pmap, va);
737 //cpu_invlpg((void *)va);
741 * Synchronize a kvm mapping originally made for the private use on
742 * some other cpu so it can be used on all cpus.
744 * XXX add MADV_RESYNC to improve performance.
747 pmap_kenter_sync(vm_offset_t va)
749 madvise((void *)va, PAGE_SIZE, MADV_INVAL);
753 * Synchronize a kvm mapping originally made for the private use on
754 * some other cpu so it can be used on our cpu. Turns out to be the
755 * same madvise() call, because we have to sync the real pmaps anyway.
757 * XXX add MADV_RESYNC to improve performance.
760 pmap_kenter_sync_quick(vm_offset_t va)
762 madvise((void *)va, PAGE_SIZE, MADV_INVAL);
766 * Remove an unmanaged mapping created with pmap_kenter*().
769 pmap_kremove(vm_offset_t va)
773 KKASSERT(va >= KvaStart && va < KvaEnd);
777 pmap_inval_pte(pte, &kernel_pmap, va);
782 * Remove an unmanaged mapping created with pmap_kenter*() but synchronize
783 * only with this cpu.
785 * Unfortunately because we optimize new entries by testing VPTE_V later
786 * on, we actually still have to synchronize with all the cpus. XXX maybe
787 * store a junk value and test against 0 in the other places instead?
790 pmap_kremove_quick(vm_offset_t va)
794 KKASSERT(va >= KvaStart && va < KvaEnd);
798 pmap_inval_pte(pte, &kernel_pmap, va); /* NOT _quick */
803 * Used to map a range of physical addresses into kernel
804 * virtual address space.
806 * For now, VM is already on, we only need to map the
810 pmap_map(vm_offset_t *virtp, vm_paddr_t start, vm_paddr_t end, int prot)
812 return PHYS_TO_DMAP(start);
817 * Map a set of unmanaged VM pages into KVM.
820 pmap_qenter(vm_offset_t va, vm_page_t *m, int count)
824 end_va = va + count * PAGE_SIZE;
825 KKASSERT(va >= KvaStart && end_va < KvaEnd);
827 while (va < end_va) {
832 pmap_inval_pte(pte, &kernel_pmap, va);
833 *pte = VM_PAGE_TO_PHYS(*m) | VPTE_R | VPTE_W | VPTE_V;
840 * Undo the effects of pmap_qenter*().
843 pmap_qremove(vm_offset_t va, int count)
847 end_va = va + count * PAGE_SIZE;
848 KKASSERT(va >= KvaStart && end_va < KvaEnd);
850 while (va < end_va) {
855 pmap_inval_pte(pte, &kernel_pmap, va);
862 * This routine works like vm_page_lookup() but also blocks as long as the
863 * page is busy. This routine does not busy the page it returns.
865 * Unless the caller is managing objects whos pages are in a known state,
866 * the call should be made with a critical section held so the page's object
867 * association remains valid on return.
870 pmap_page_lookup(vm_object_t object, vm_pindex_t pindex)
874 ASSERT_LWKT_TOKEN_HELD(vm_object_token(object));
875 m = vm_page_lookup_busy_wait(object, pindex, FALSE, "pplookp");
881 * Create a new thread and optionally associate it with a (new) process.
882 * NOTE! the new thread's cpu may not equal the current cpu.
885 pmap_init_thread(thread_t td)
887 /* enforce pcb placement */
888 td->td_pcb = (struct pcb *)(td->td_kstack + td->td_kstack_size) - 1;
889 td->td_savefpu = &td->td_pcb->pcb_save;
890 td->td_sp = (char *)td->td_pcb - 16; /* JG is -16 needed on x86_64? */
894 * This routine directly affects the fork perf for a process.
897 pmap_init_proc(struct proc *p)
902 * Dispose the UPAGES for a process that has exited.
903 * This routine directly impacts the exit perf of a process.
906 pmap_dispose_proc(struct proc *p)
908 KASSERT(p->p_lock == 0, ("attempt to dispose referenced proc! %p", p));
911 /***************************************************
912 * Page table page management routines.....
913 ***************************************************/
915 static __inline int pmap_unwire_pte_hold(pmap_t pmap, vm_offset_t va,
919 * This routine unholds page table pages, and if the hold count
920 * drops to zero, then it decrements the wire count.
922 * We must recheck that this is the last hold reference after busy-sleeping
926 _pmap_unwire_pte_hold(pmap_t pmap, vm_offset_t va, vm_page_t m)
928 vm_page_busy_wait(m, FALSE, "pmuwpt");
929 KASSERT(m->queue == PQ_NONE,
930 ("_pmap_unwire_pte_hold: %p->queue != PQ_NONE", m));
932 if (m->hold_count == 1) {
934 * Unmap the page table page.
937 /* pmap_inval_add(info, pmap, -1); */
939 if (m->pindex >= (NUPDE + NUPDPE)) {
942 pml4 = pmap_pml4e(pmap, va);
944 } else if (m->pindex >= NUPDE) {
947 pdp = pmap_pdpe(pmap, va);
952 pd = pmap_pde(pmap, va);
956 KKASSERT(pmap->pm_stats.resident_count > 0);
957 --pmap->pm_stats.resident_count;
959 if (pmap->pm_ptphint == m)
960 pmap->pm_ptphint = NULL;
962 if (m->pindex < NUPDE) {
963 /* We just released a PT, unhold the matching PD */
966 pdpg = PHYS_TO_VM_PAGE(*pmap_pdpe(pmap, va) & VPTE_FRAME);
967 pmap_unwire_pte_hold(pmap, va, pdpg);
969 if (m->pindex >= NUPDE && m->pindex < (NUPDE + NUPDPE)) {
970 /* We just released a PD, unhold the matching PDP */
973 pdppg = PHYS_TO_VM_PAGE(*pmap_pml4e(pmap, va) & VPTE_FRAME);
974 pmap_unwire_pte_hold(pmap, va, pdppg);
978 * This was our last hold, the page had better be unwired
979 * after we decrement wire_count.
981 * FUTURE NOTE: shared page directory page could result in
982 * multiple wire counts.
986 KKASSERT(m->wire_count == 0);
987 atomic_add_int(&vmstats.v_wire_count, -1);
988 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
990 vm_page_free_zero(m);
993 KKASSERT(m->hold_count > 1);
1001 pmap_unwire_pte_hold(pmap_t pmap, vm_offset_t va, vm_page_t m)
1003 KKASSERT(m->hold_count > 0);
1004 if (m->hold_count > 1) {
1008 return _pmap_unwire_pte_hold(pmap, va, m);
1013 * After removing a page table entry, this routine is used to
1014 * conditionally free the page, and manage the hold/wire counts.
1017 pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte)
1019 /* JG Use FreeBSD/amd64 or FreeBSD/i386 ptepde approaches? */
1020 vm_pindex_t ptepindex;
1022 ASSERT_LWKT_TOKEN_HELD(vm_object_token(pmap->pm_pteobj));
1026 * page table pages in the kernel_pmap are not managed.
1028 if (pmap == &kernel_pmap)
1030 ptepindex = pmap_pde_pindex(va);
1031 if (pmap->pm_ptphint &&
1032 (pmap->pm_ptphint->pindex == ptepindex)) {
1033 mpte = pmap->pm_ptphint;
1035 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex);
1036 pmap->pm_ptphint = mpte;
1037 vm_page_wakeup(mpte);
1041 return pmap_unwire_pte_hold(pmap, va, mpte);
1045 * Initialize pmap0/vmspace0 . Since process 0 never enters user mode we
1046 * just dummy it up so it works well enough for fork().
1048 * In DragonFly, process pmaps may only be used to manipulate user address
1049 * space, never kernel address space.
1052 pmap_pinit0(struct pmap *pmap)
1058 * Initialize a preallocated and zeroed pmap structure,
1059 * such as one in a vmspace structure.
1062 pmap_pinit(struct pmap *pmap)
1067 * No need to allocate page table space yet but we do need a valid
1068 * page directory table.
1070 if (pmap->pm_pml4 == NULL) {
1072 (pml4_entry_t *)kmem_alloc_pageable(&kernel_map, PAGE_SIZE);
1076 * Allocate an object for the ptes
1078 if (pmap->pm_pteobj == NULL)
1079 pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, NUPDE + NUPDPE + PML4PML4I + 1);
1082 * Allocate the page directory page, unless we already have
1083 * one cached. If we used the cached page the wire_count will
1084 * already be set appropriately.
1086 if ((ptdpg = pmap->pm_pdirm) == NULL) {
1087 ptdpg = vm_page_grab(pmap->pm_pteobj, NUPDE + NUPDPE + PML4PML4I,
1088 VM_ALLOC_NORMAL | VM_ALLOC_RETRY);
1089 pmap->pm_pdirm = ptdpg;
1090 vm_page_flag_clear(ptdpg, PG_MAPPED);
1091 ptdpg->valid = VM_PAGE_BITS_ALL;
1092 if (ptdpg->wire_count == 0)
1093 atomic_add_int(&vmstats.v_wire_count, 1);
1094 ptdpg->wire_count = 1;
1095 vm_page_wakeup(ptdpg);
1096 pmap_kenter((vm_offset_t)pmap->pm_pml4, VM_PAGE_TO_PHYS(ptdpg));
1098 if ((ptdpg->flags & PG_ZERO) == 0)
1099 bzero(pmap->pm_pml4, PAGE_SIZE);
1100 vm_page_flag_clear(ptdpg, PG_ZERO);
1103 pmap->pm_active = 0;
1104 pmap->pm_ptphint = NULL;
1105 TAILQ_INIT(&pmap->pm_pvlist);
1106 TAILQ_INIT(&pmap->pm_pvlist_free);
1107 spin_init(&pmap->pm_spin);
1108 lwkt_token_init(&pmap->pm_token, "pmap_tok");
1109 bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
1110 pmap->pm_stats.resident_count = 1;
1114 * Clean up a pmap structure so it can be physically freed. This routine
1115 * is called by the vmspace dtor function. A great deal of pmap data is
1116 * left passively mapped to improve vmspace management so we have a bit
1117 * of cleanup work to do here.
1122 pmap_puninit(pmap_t pmap)
1126 KKASSERT(pmap->pm_active == 0);
1127 if ((p = pmap->pm_pdirm) != NULL) {
1128 KKASSERT(pmap->pm_pml4 != NULL);
1129 pmap_kremove((vm_offset_t)pmap->pm_pml4);
1130 vm_page_busy_wait(p, FALSE, "pgpun");
1132 atomic_add_int(&vmstats.v_wire_count, -1);
1133 vm_page_free_zero(p);
1134 pmap->pm_pdirm = NULL;
1136 if (pmap->pm_pml4) {
1137 kmem_free(&kernel_map, (vm_offset_t)pmap->pm_pml4, PAGE_SIZE);
1138 pmap->pm_pml4 = NULL;
1140 if (pmap->pm_pteobj) {
1141 vm_object_deallocate(pmap->pm_pteobj);
1142 pmap->pm_pteobj = NULL;
1147 * Wire in kernel global address entries. To avoid a race condition
1148 * between pmap initialization and pmap_growkernel, this procedure
1149 * adds the pmap to the master list (which growkernel scans to update),
1150 * then copies the template.
1152 * In a virtual kernel there are no kernel global address entries.
1157 pmap_pinit2(struct pmap *pmap)
1159 spin_lock(&pmap_spin);
1160 TAILQ_INSERT_TAIL(&pmap_list, pmap, pm_pmnode);
1161 spin_unlock(&pmap_spin);
1165 * Attempt to release and free a vm_page in a pmap. Returns 1 on success,
1166 * 0 on failure (if the procedure had to sleep).
1168 * When asked to remove the page directory page itself, we actually just
1169 * leave it cached so we do not have to incur the SMP inval overhead of
1170 * removing the kernel mapping. pmap_puninit() will take care of it.
1173 pmap_release_free_page(struct pmap *pmap, vm_page_t p)
1176 * This code optimizes the case of freeing non-busy
1177 * page-table pages. Those pages are zero now, and
1178 * might as well be placed directly into the zero queue.
1180 if (vm_page_busy_try(p, FALSE)) {
1181 vm_page_sleep_busy(p, FALSE, "pmaprl");
1186 * Remove the page table page from the processes address space.
1188 if (p->pindex == NUPDE + NUPDPE + PML4PML4I) {
1190 * We are the pml4 table itself.
1192 /* XXX anything to do here? */
1193 } else if (p->pindex >= (NUPDE + NUPDPE)) {
1195 * We are a PDP page.
1196 * We look for the PML4 entry that points to us.
1198 vm_page_t m4 = vm_page_lookup(pmap->pm_pteobj, NUPDE + NUPDPE + PML4PML4I);
1199 KKASSERT(m4 != NULL);
1200 pml4_entry_t *pml4 = (pml4_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m4));
1201 int idx = (p->pindex - (NUPDE + NUPDPE)) % NPML4EPG;
1202 KKASSERT(pml4[idx] != 0);
1205 /* JG What about wire_count? */
1206 } else if (p->pindex >= NUPDE) {
1209 * We look for the PDP entry that points to us.
1211 vm_page_t m3 = vm_page_lookup(pmap->pm_pteobj, NUPDE + NUPDPE + (p->pindex - NUPDE) / NPDPEPG);
1212 KKASSERT(m3 != NULL);
1213 pdp_entry_t *pdp = (pdp_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m3));
1214 int idx = (p->pindex - NUPDE) % NPDPEPG;
1215 KKASSERT(pdp[idx] != 0);
1218 /* JG What about wire_count? */
1220 /* We are a PT page.
1221 * We look for the PD entry that points to us.
1223 vm_page_t m2 = vm_page_lookup(pmap->pm_pteobj, NUPDE + p->pindex / NPDEPG);
1224 KKASSERT(m2 != NULL);
1225 pd_entry_t *pd = (pd_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m2));
1226 int idx = p->pindex % NPDEPG;
1229 /* JG What about wire_count? */
1231 KKASSERT(pmap->pm_stats.resident_count > 0);
1232 --pmap->pm_stats.resident_count;
1234 if (p->hold_count) {
1235 panic("pmap_release: freeing held page table page");
1237 if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex))
1238 pmap->pm_ptphint = NULL;
1241 * We leave the top-level page table page cached, wired, and mapped in
1242 * the pmap until the dtor function (pmap_puninit()) gets called.
1243 * However, still clean it up so we can set PG_ZERO.
1245 if (p->pindex == NUPDE + NUPDPE + PML4PML4I) {
1246 bzero(pmap->pm_pml4, PAGE_SIZE);
1247 vm_page_flag_set(p, PG_ZERO);
1252 atomic_add_int(&vmstats.v_wire_count, -1);
1253 /* JG eventually revert to using vm_page_free_zero() */
1260 * this routine is called if the page table page is not
1264 _pmap_allocpte(pmap_t pmap, vm_pindex_t ptepindex)
1266 vm_page_t m, pdppg, pdpg;
1269 * Find or fabricate a new pagetable page. Handle allocation
1270 * races by checking m->valid.
1272 m = vm_page_grab(pmap->pm_pteobj, ptepindex,
1273 VM_ALLOC_NORMAL | VM_ALLOC_ZERO | VM_ALLOC_RETRY);
1275 if (m->valid == 0) {
1276 if ((m->flags & PG_ZERO) == 0) {
1277 pmap_zero_page(VM_PAGE_TO_PHYS(m));
1279 m->valid = VM_PAGE_BITS_ALL;
1280 vm_page_flag_clear(m, PG_ZERO);
1282 KKASSERT((m->flags & PG_ZERO) == 0);
1285 KASSERT(m->queue == PQ_NONE,
1286 ("_pmap_allocpte: %p->queue != PQ_NONE", m));
1289 * Increment the hold count for the page we will be returning to
1294 if (m->wire_count == 0)
1295 atomic_add_int(&vmstats.v_wire_count, 1);
1299 * Map the pagetable page into the process address space, if
1300 * it isn't already there.
1302 ++pmap->pm_stats.resident_count;
1304 if (ptepindex >= (NUPDE + NUPDPE)) {
1306 vm_pindex_t pml4index;
1308 /* Wire up a new PDP page */
1309 pml4index = ptepindex - (NUPDE + NUPDPE);
1310 pml4 = &pmap->pm_pml4[pml4index];
1311 *pml4 = VM_PAGE_TO_PHYS(m) | VPTE_R | VPTE_W | VPTE_V |
1313 } else if (ptepindex >= NUPDE) {
1314 vm_pindex_t pml4index;
1315 vm_pindex_t pdpindex;
1319 /* Wire up a new PD page */
1320 pdpindex = ptepindex - NUPDE;
1321 pml4index = pdpindex >> NPML4EPGSHIFT;
1323 pml4 = &pmap->pm_pml4[pml4index];
1324 if ((*pml4 & VPTE_V) == 0) {
1325 /* Have to allocate a new PDP page, recurse */
1326 if (_pmap_allocpte(pmap, NUPDE + NUPDPE + pml4index)
1333 /* Add reference to the PDP page */
1334 pdppg = PHYS_TO_VM_PAGE(*pml4 & VPTE_FRAME);
1335 pdppg->hold_count++;
1337 pdp = (pdp_entry_t *)PHYS_TO_DMAP(*pml4 & VPTE_FRAME);
1339 /* Now find the pdp page */
1340 pdp = &pdp[pdpindex & ((1ul << NPDPEPGSHIFT) - 1)];
1341 KKASSERT(*pdp == 0); /* JG DEBUG64 */
1342 *pdp = VM_PAGE_TO_PHYS(m) | VPTE_R | VPTE_W | VPTE_V |
1345 vm_pindex_t pml4index;
1346 vm_pindex_t pdpindex;
1351 /* Wire up a new PT page */
1352 pdpindex = ptepindex >> NPDPEPGSHIFT;
1353 pml4index = pdpindex >> NPML4EPGSHIFT;
1355 /* First, find the pdp and check that its valid. */
1356 pml4 = &pmap->pm_pml4[pml4index];
1357 if ((*pml4 & VPTE_V) == 0) {
1358 /* We miss a PDP page. We ultimately need a PD page.
1359 * Recursively allocating a PD page will allocate
1360 * the missing PDP page and will also allocate
1361 * the PD page we need.
1363 /* Have to allocate a new PD page, recurse */
1364 if (_pmap_allocpte(pmap, NUPDE + pdpindex)
1370 pdp = (pdp_entry_t *)PHYS_TO_DMAP(*pml4 & VPTE_FRAME);
1371 pdp = &pdp[pdpindex & ((1ul << NPDPEPGSHIFT) - 1)];
1373 pdp = (pdp_entry_t *)PHYS_TO_DMAP(*pml4 & VPTE_FRAME);
1374 pdp = &pdp[pdpindex & ((1ul << NPDPEPGSHIFT) - 1)];
1375 if ((*pdp & VPTE_V) == 0) {
1376 /* Have to allocate a new PD page, recurse */
1377 if (_pmap_allocpte(pmap, NUPDE + pdpindex)
1384 /* Add reference to the PD page */
1385 pdpg = PHYS_TO_VM_PAGE(*pdp & VPTE_FRAME);
1389 pd = (pd_entry_t *)PHYS_TO_DMAP(*pdp & VPTE_FRAME);
1391 /* Now we know where the page directory page is */
1392 pd = &pd[ptepindex & ((1ul << NPDEPGSHIFT) - 1)];
1393 KKASSERT(*pd == 0); /* JG DEBUG64 */
1394 *pd = VM_PAGE_TO_PHYS(m) | VPTE_R | VPTE_W | VPTE_V |
1399 * Set the page table hint
1401 pmap->pm_ptphint = m;
1402 vm_page_flag_set(m, PG_MAPPED);
1409 * Determine the page table page required to access the VA in the pmap
1410 * and allocate it if necessary. Return a held vm_page_t for the page.
1412 * Only used with user pmaps.
1415 pmap_allocpte(pmap_t pmap, vm_offset_t va)
1417 vm_pindex_t ptepindex;
1421 ASSERT_LWKT_TOKEN_HELD(vm_object_token(pmap->pm_pteobj));
1424 * Calculate pagetable page index
1426 ptepindex = pmap_pde_pindex(va);
1429 * Get the page directory entry
1431 pd = pmap_pde(pmap, va);
1434 * This supports switching from a 2MB page to a
1437 if (pd != NULL && (*pd & (VPTE_PS | VPTE_V)) == (VPTE_PS | VPTE_V)) {
1438 panic("no promotion/demotion yet");
1446 * If the page table page is mapped, we just increment the
1447 * hold count, and activate it.
1449 if (pd != NULL && (*pd & VPTE_V) != 0) {
1450 /* YYY hint is used here on i386 */
1451 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex);
1452 pmap->pm_ptphint = m;
1458 * Here if the pte page isn't mapped, or if it has been deallocated.
1460 return _pmap_allocpte(pmap, ptepindex);
1464 /***************************************************
1465 * Pmap allocation/deallocation routines.
1466 ***************************************************/
1469 * Release any resources held by the given physical map.
1470 * Called when a pmap initialized by pmap_pinit is being released.
1471 * Should only be called if the map contains no valid mappings.
1473 * Caller must hold pmap->pm_token
1475 static int pmap_release_callback(struct vm_page *p, void *data);
1478 pmap_release(struct pmap *pmap)
1480 vm_object_t object = pmap->pm_pteobj;
1481 struct rb_vm_page_scan_info info;
1483 KKASSERT(pmap != &kernel_pmap);
1485 #if defined(DIAGNOSTIC)
1486 if (object->ref_count != 1)
1487 panic("pmap_release: pteobj reference count != 1");
1491 info.object = object;
1493 spin_lock(&pmap_spin);
1494 TAILQ_REMOVE(&pmap_list, pmap, pm_pmnode);
1495 spin_unlock(&pmap_spin);
1497 vm_object_hold(object);
1501 info.limit = object->generation;
1503 vm_page_rb_tree_RB_SCAN(&object->rb_memq, NULL,
1504 pmap_release_callback, &info);
1505 if (info.error == 0 && info.mpte) {
1506 if (!pmap_release_free_page(pmap, info.mpte))
1509 } while (info.error);
1510 vm_object_drop(object);
1514 pmap_release_callback(struct vm_page *p, void *data)
1516 struct rb_vm_page_scan_info *info = data;
1518 if (p->pindex == NUPDE + NUPDPE + PML4PML4I) {
1522 if (!pmap_release_free_page(info->pmap, p)) {
1526 if (info->object->generation != info->limit) {
1534 * Grow the number of kernel page table entries, if needed.
1539 pmap_growkernel(vm_offset_t kstart, vm_offset_t kend)
1543 vm_offset_t ptppaddr;
1545 pd_entry_t *pde, newpdir;
1550 vm_object_hold(kptobj);
1551 if (kernel_vm_end == 0) {
1552 kernel_vm_end = KvaStart;
1554 while ((*pmap_pde(&kernel_pmap, kernel_vm_end) & VPTE_V) != 0) {
1555 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;
1563 addr = roundup2(addr, PAGE_SIZE * NPTEPG);
1564 if (addr - 1 >= kernel_map.max_offset)
1565 addr = kernel_map.max_offset;
1566 while (kernel_vm_end < addr) {
1567 pde = pmap_pde(&kernel_pmap, kernel_vm_end);
1569 /* We need a new PDP entry */
1570 nkpg = vm_page_alloc(kptobj, nkpt,
1571 VM_ALLOC_NORMAL | VM_ALLOC_SYSTEM
1572 | VM_ALLOC_INTERRUPT);
1574 panic("pmap_growkernel: no memory to "
1577 paddr = VM_PAGE_TO_PHYS(nkpg);
1578 if ((nkpg->flags & PG_ZERO) == 0)
1579 pmap_zero_page(paddr);
1580 vm_page_flag_clear(nkpg, PG_ZERO);
1581 newpdp = (pdp_entry_t)(paddr | VPTE_V | VPTE_R |
1582 VPTE_W | VPTE_A | VPTE_M);
1583 *pmap_pdpe(&kernel_pmap, kernel_vm_end) = newpdp;
1585 continue; /* try again */
1587 if ((*pde & VPTE_V) != 0) {
1588 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) &
1589 ~(PAGE_SIZE * NPTEPG - 1);
1590 if (kernel_vm_end - 1 >= kernel_map.max_offset) {
1591 kernel_vm_end = kernel_map.max_offset;
1598 * This index is bogus, but out of the way
1600 nkpg = vm_page_alloc(kptobj, nkpt,
1603 VM_ALLOC_INTERRUPT);
1605 panic("pmap_growkernel: no memory to grow kernel");
1608 ptppaddr = VM_PAGE_TO_PHYS(nkpg);
1609 pmap_zero_page(ptppaddr);
1610 vm_page_flag_clear(nkpg, PG_ZERO);
1611 newpdir = (pd_entry_t)(ptppaddr | VPTE_V | VPTE_R |
1612 VPTE_W | VPTE_A | VPTE_M);
1613 *pmap_pde(&kernel_pmap, kernel_vm_end) = newpdir;
1616 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) &
1617 ~(PAGE_SIZE * NPTEPG - 1);
1618 if (kernel_vm_end - 1 >= kernel_map.max_offset) {
1619 kernel_vm_end = kernel_map.max_offset;
1623 vm_object_drop(kptobj);
1627 * Retire the given physical map from service. Should only be called
1628 * if the map contains no valid mappings.
1633 pmap_destroy(pmap_t pmap)
1638 lwkt_gettoken(&vm_token);
1639 if (--pmap->pm_count == 0) {
1641 panic("destroying a pmap is not yet implemented");
1643 lwkt_reltoken(&vm_token);
1647 * Add a reference to the specified pmap.
1652 pmap_reference(pmap_t pmap)
1655 lwkt_gettoken(&vm_token);
1657 lwkt_reltoken(&vm_token);
1661 /************************************************************************
1662 * VMSPACE MANAGEMENT *
1663 ************************************************************************
1665 * The VMSPACE management we do in our virtual kernel must be reflected
1666 * in the real kernel. This is accomplished by making vmspace system
1667 * calls to the real kernel.
1670 cpu_vmspace_alloc(struct vmspace *vm)
1676 #define USER_SIZE (VM_MAX_USER_ADDRESS - VM_MIN_USER_ADDRESS)
1678 if (vmspace_create(&vm->vm_pmap, 0, NULL) < 0)
1679 panic("vmspace_create() failed");
1681 rp = vmspace_mmap(&vm->vm_pmap, VM_MIN_USER_ADDRESS, USER_SIZE,
1682 PROT_READ|PROT_WRITE,
1683 MAP_FILE|MAP_SHARED|MAP_VPAGETABLE|MAP_FIXED,
1685 if (rp == MAP_FAILED)
1686 panic("vmspace_mmap: failed");
1687 vmspace_mcontrol(&vm->vm_pmap, VM_MIN_USER_ADDRESS, USER_SIZE,
1689 vpte = VM_PAGE_TO_PHYS(vmspace_pmap(vm)->pm_pdirm) | VPTE_R | VPTE_W | VPTE_V;
1690 r = vmspace_mcontrol(&vm->vm_pmap, VM_MIN_USER_ADDRESS, USER_SIZE,
1693 panic("vmspace_mcontrol: failed");
1697 cpu_vmspace_free(struct vmspace *vm)
1699 if (vmspace_destroy(&vm->vm_pmap) < 0)
1700 panic("vmspace_destroy() failed");
1703 /***************************************************
1704 * page management routines.
1705 ***************************************************/
1708 * free the pv_entry back to the free list. This function may be
1709 * called from an interrupt.
1711 static __inline void
1712 free_pv_entry(pv_entry_t pv)
1715 KKASSERT(pv_entry_count >= 0);
1720 * get a new pv_entry, allocating a block from the system
1721 * when needed. This function may be called from an interrupt.
1727 if (pv_entry_high_water &&
1728 (pv_entry_count > pv_entry_high_water) &&
1729 (pmap_pagedaemon_waken == 0)) {
1730 pmap_pagedaemon_waken = 1;
1731 wakeup(&vm_pages_needed);
1733 return zalloc(pvzone);
1737 * This routine is very drastic, but can save the system
1747 static int warningdone=0;
1749 if (pmap_pagedaemon_waken == 0)
1751 lwkt_gettoken(&vm_token);
1752 pmap_pagedaemon_waken = 0;
1754 if (warningdone < 5) {
1755 kprintf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n");
1759 for (i = 0; i < vm_page_array_size; i++) {
1760 m = &vm_page_array[i];
1761 if (m->wire_count || m->hold_count)
1763 if (vm_page_busy_try(m, TRUE) == 0) {
1764 if (m->wire_count == 0 && m->hold_count == 0) {
1770 lwkt_reltoken(&vm_token);
1775 * If it is the first entry on the list, it is actually
1776 * in the header and we must copy the following entry up
1777 * to the header. Otherwise we must search the list for
1778 * the entry. In either case we free the now unused entry.
1780 * caller must hold vm_token.
1783 pmap_remove_entry(struct pmap *pmap, vm_page_t m, vm_offset_t va)
1788 if (m->md.pv_list_count < pmap->pm_stats.resident_count) {
1789 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
1790 if (pmap == pv->pv_pmap && va == pv->pv_va)
1794 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) {
1795 if (va == pv->pv_va)
1801 * Note that pv_ptem is NULL if the page table page itself is not
1802 * managed, even if the page being removed IS managed.
1805 /* JGXXX When can 'pv' be NULL? */
1807 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
1808 m->md.pv_list_count--;
1809 atomic_add_int(&m->object->agg_pv_list_count, -1);
1810 KKASSERT(m->md.pv_list_count >= 0);
1811 if (TAILQ_EMPTY(&m->md.pv_list))
1812 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
1813 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist);
1814 ++pmap->pm_generation;
1815 KKASSERT(pmap->pm_pteobj != NULL);
1816 vm_object_hold(pmap->pm_pteobj);
1817 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem);
1818 vm_object_drop(pmap->pm_pteobj);
1825 * Create a pv entry for page at pa for (pmap, va). If the page table page
1826 * holding the VA is managed, mpte will be non-NULL.
1829 pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m)
1834 pv = get_pv_entry();
1839 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist);
1840 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
1841 m->md.pv_list_count++;
1842 atomic_add_int(&m->object->agg_pv_list_count, 1);
1848 * pmap_remove_pte: do the things to unmap a page in a process
1851 pmap_remove_pte(struct pmap *pmap, pt_entry_t *ptq, vm_offset_t va)
1856 oldpte = pmap_inval_loadandclear(ptq, pmap, va);
1857 if (oldpte & VPTE_WIRED)
1858 --pmap->pm_stats.wired_count;
1859 KKASSERT(pmap->pm_stats.wired_count >= 0);
1863 * Machines that don't support invlpg, also don't support
1864 * PG_G. XXX PG_G is disabled for SMP so don't worry about
1868 cpu_invlpg((void *)va);
1870 KKASSERT(pmap->pm_stats.resident_count > 0);
1871 --pmap->pm_stats.resident_count;
1872 if (oldpte & VPTE_MANAGED) {
1873 m = PHYS_TO_VM_PAGE(oldpte);
1874 if (oldpte & VPTE_M) {
1875 #if defined(PMAP_DIAGNOSTIC)
1876 if (pmap_nw_modified((pt_entry_t) oldpte)) {
1877 kprintf("pmap_remove: modified page not "
1878 "writable: va: 0x%lx, pte: 0x%lx\n",
1882 if (pmap_track_modified(pmap, va))
1885 if (oldpte & VPTE_A)
1886 vm_page_flag_set(m, PG_REFERENCED);
1887 return pmap_remove_entry(pmap, m, va);
1889 return pmap_unuse_pt(pmap, va, NULL);
1898 * Remove a single page from a process address space.
1900 * This function may not be called from an interrupt if the pmap is
1904 pmap_remove_page(struct pmap *pmap, vm_offset_t va)
1908 pte = pmap_pte(pmap, va);
1911 if ((*pte & VPTE_V) == 0)
1913 pmap_remove_pte(pmap, pte, va);
1917 * Remove the given range of addresses from the specified map.
1919 * It is assumed that the start and end are properly rounded to
1922 * This function may not be called from an interrupt if the pmap is
1928 pmap_remove(struct pmap *pmap, vm_offset_t sva, vm_offset_t eva)
1930 vm_offset_t va_next;
1931 pml4_entry_t *pml4e;
1933 pd_entry_t ptpaddr, *pde;
1939 vm_object_hold(pmap->pm_pteobj);
1940 lwkt_gettoken(&vm_token);
1941 KKASSERT(pmap->pm_stats.resident_count >= 0);
1942 if (pmap->pm_stats.resident_count == 0) {
1943 lwkt_reltoken(&vm_token);
1944 vm_object_drop(pmap->pm_pteobj);
1949 * special handling of removing one page. a very
1950 * common operation and easy to short circuit some
1953 if (sva + PAGE_SIZE == eva) {
1954 pde = pmap_pde(pmap, sva);
1955 if (pde && (*pde & VPTE_PS) == 0) {
1956 pmap_remove_page(pmap, sva);
1957 lwkt_reltoken(&vm_token);
1958 vm_object_drop(pmap->pm_pteobj);
1963 for (; sva < eva; sva = va_next) {
1964 pml4e = pmap_pml4e(pmap, sva);
1965 if ((*pml4e & VPTE_V) == 0) {
1966 va_next = (sva + NBPML4) & ~PML4MASK;
1972 pdpe = pmap_pml4e_to_pdpe(pml4e, sva);
1973 if ((*pdpe & VPTE_V) == 0) {
1974 va_next = (sva + NBPDP) & ~PDPMASK;
1981 * Calculate index for next page table.
1983 va_next = (sva + NBPDR) & ~PDRMASK;
1987 pde = pmap_pdpe_to_pde(pdpe, sva);
1991 * Weed out invalid mappings.
1997 * Check for large page.
1999 if ((ptpaddr & VPTE_PS) != 0) {
2000 /* JG FreeBSD has more complex treatment here */
2001 KKASSERT(*pde != 0);
2002 pmap_inval_pde(pde, pmap, sva);
2003 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
2008 * Limit our scan to either the end of the va represented
2009 * by the current page table page, or to the end of the
2010 * range being removed.
2016 * NOTE: pmap_remove_pte() can block.
2018 for (pte = pmap_pde_to_pte(pde, sva); sva != va_next; pte++,
2022 if (pmap_remove_pte(pmap, pte, sva))
2026 lwkt_reltoken(&vm_token);
2027 vm_object_drop(pmap->pm_pteobj);
2031 * Removes this physical page from all physical maps in which it resides.
2032 * Reflects back modify bits to the pager.
2034 * This routine may not be called from an interrupt.
2039 pmap_remove_all(vm_page_t m)
2041 pt_entry_t *pte, tpte;
2044 #if defined(PMAP_DIAGNOSTIC)
2046 * XXX this makes pmap_page_protect(NONE) illegal for non-managed
2049 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) {
2050 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%08llx", (long long)VM_PAGE_TO_PHYS(m));
2054 lwkt_gettoken(&vm_token);
2055 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
2056 KKASSERT(pv->pv_pmap->pm_stats.resident_count > 0);
2057 --pv->pv_pmap->pm_stats.resident_count;
2059 pte = pmap_pte(pv->pv_pmap, pv->pv_va);
2060 KKASSERT(pte != NULL);
2062 tpte = pmap_inval_loadandclear(pte, pv->pv_pmap, pv->pv_va);
2063 if (tpte & VPTE_WIRED)
2064 pv->pv_pmap->pm_stats.wired_count--;
2065 KKASSERT(pv->pv_pmap->pm_stats.wired_count >= 0);
2068 vm_page_flag_set(m, PG_REFERENCED);
2071 * Update the vm_page_t clean and reference bits.
2073 if (tpte & VPTE_M) {
2074 #if defined(PMAP_DIAGNOSTIC)
2075 if (pmap_nw_modified(tpte)) {
2077 "pmap_remove_all: modified page not writable: va: 0x%lx, pte: 0x%lx\n",
2081 if (pmap_track_modified(pv->pv_pmap, pv->pv_va))
2084 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
2085 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist);
2086 ++pv->pv_pmap->pm_generation;
2087 m->md.pv_list_count--;
2088 atomic_add_int(&m->object->agg_pv_list_count, -1);
2089 KKASSERT(m->md.pv_list_count >= 0);
2090 if (TAILQ_EMPTY(&m->md.pv_list))
2091 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
2092 vm_object_hold(pv->pv_pmap->pm_pteobj);
2093 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem);
2094 vm_object_drop(pv->pv_pmap->pm_pteobj);
2097 KKASSERT((m->flags & (PG_MAPPED|PG_WRITEABLE)) == 0);
2098 lwkt_reltoken(&vm_token);
2102 * Set the physical protection on the specified range of this map
2105 * This function may not be called from an interrupt if the map is
2106 * not the kernel_pmap.
2111 pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
2113 vm_offset_t va_next;
2114 pml4_entry_t *pml4e;
2116 pd_entry_t ptpaddr, *pde;
2119 /* JG review for NX */
2124 if ((prot & VM_PROT_READ) == VM_PROT_NONE) {
2125 pmap_remove(pmap, sva, eva);
2129 if (prot & VM_PROT_WRITE)
2132 lwkt_gettoken(&vm_token);
2134 for (; sva < eva; sva = va_next) {
2136 pml4e = pmap_pml4e(pmap, sva);
2137 if ((*pml4e & VPTE_V) == 0) {
2138 va_next = (sva + NBPML4) & ~PML4MASK;
2144 pdpe = pmap_pml4e_to_pdpe(pml4e, sva);
2145 if ((*pdpe & VPTE_V) == 0) {
2146 va_next = (sva + NBPDP) & ~PDPMASK;
2152 va_next = (sva + NBPDR) & ~PDRMASK;
2156 pde = pmap_pdpe_to_pde(pdpe, sva);
2160 * Check for large page.
2162 if ((ptpaddr & VPTE_PS) != 0) {
2164 pmap_clean_pde(pde, pmap, sva);
2165 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
2170 * Weed out invalid mappings. Note: we assume that the page
2171 * directory table is always allocated, and in kernel virtual.
2179 for (pte = pmap_pde_to_pte(pde, sva); sva != va_next; pte++,
2185 * Clean managed pages and also check the accessed
2186 * bit. Just remove write perms for unmanaged
2187 * pages. Be careful of races, turning off write
2188 * access will force a fault rather then setting
2189 * the modified bit at an unexpected time.
2191 if (*pte & VPTE_MANAGED) {
2192 pbits = pmap_clean_pte(pte, pmap, sva);
2194 if (pbits & VPTE_A) {
2195 m = PHYS_TO_VM_PAGE(pbits & VPTE_FRAME);
2196 vm_page_flag_set(m, PG_REFERENCED);
2197 atomic_clear_long(pte, VPTE_A);
2199 if (pbits & VPTE_M) {
2200 if (pmap_track_modified(pmap, sva)) {
2202 m = PHYS_TO_VM_PAGE(pbits & VPTE_FRAME);
2207 pbits = pmap_setro_pte(pte, pmap, sva);
2211 lwkt_reltoken(&vm_token);
2215 * Enter a managed page into a pmap. If the page is not wired related pmap
2216 * data can be destroyed at any time for later demand-operation.
2218 * Insert the vm_page (m) at virtual address (v) in (pmap), with the
2219 * specified protection, and wire the mapping if requested.
2221 * NOTE: This routine may not lazy-evaluate or lose information. The
2222 * page must actually be inserted into the given map NOW.
2224 * NOTE: When entering a page at a KVA address, the pmap must be the
2230 pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
2237 pt_entry_t origpte, newpte;
2243 va = trunc_page(va);
2245 vm_object_hold(pmap->pm_pteobj);
2246 lwkt_gettoken(&vm_token);
2249 * Get the page table page. The kernel_pmap's page table pages
2250 * are preallocated and have no associated vm_page_t.
2252 if (pmap == &kernel_pmap)
2255 mpte = pmap_allocpte(pmap, va);
2257 pde = pmap_pde(pmap, va);
2258 if (pde != NULL && (*pde & VPTE_V) != 0) {
2259 if ((*pde & VPTE_PS) != 0)
2260 panic("pmap_enter: attempted pmap_enter on 2MB page");
2261 pte = pmap_pde_to_pte(pde, va);
2263 panic("pmap_enter: invalid page directory va=%#lx", va);
2266 KKASSERT(pte != NULL);
2268 * Deal with races on the original mapping (though don't worry
2269 * about VPTE_A races) by cleaning it. This will force a fault
2270 * if an attempt is made to write to the page.
2272 pa = VM_PAGE_TO_PHYS(m);
2273 origpte = pmap_clean_pte(pte, pmap, va);
2274 opa = origpte & VPTE_FRAME;
2276 if (origpte & VPTE_PS)
2277 panic("pmap_enter: attempted pmap_enter on 2MB page");
2280 * Mapping has not changed, must be protection or wiring change.
2282 if (origpte && (opa == pa)) {
2284 * Wiring change, just update stats. We don't worry about
2285 * wiring PT pages as they remain resident as long as there
2286 * are valid mappings in them. Hence, if a user page is wired,
2287 * the PT page will be also.
2289 if (wired && ((origpte & VPTE_WIRED) == 0))
2290 ++pmap->pm_stats.wired_count;
2291 else if (!wired && (origpte & VPTE_WIRED))
2292 --pmap->pm_stats.wired_count;
2295 * Remove the extra pte reference. Note that we cannot
2296 * optimize the RO->RW case because we have adjusted the
2297 * wiring count above and may need to adjust the wiring
2304 * We might be turning off write access to the page,
2305 * so we go ahead and sense modify status.
2307 if (origpte & VPTE_MANAGED) {
2308 if ((origpte & VPTE_M) &&
2309 pmap_track_modified(pmap, va)) {
2311 om = PHYS_TO_VM_PAGE(opa);
2315 KKASSERT(m->flags & PG_MAPPED);
2320 * Mapping has changed, invalidate old range and fall through to
2321 * handle validating new mapping.
2325 err = pmap_remove_pte(pmap, pte, va);
2327 panic("pmap_enter: pte vanished, va: 0x%lx", va);
2331 * Enter on the PV list if part of our managed memory. Note that we
2332 * raise IPL while manipulating pv_table since pmap_enter can be
2333 * called at interrupt time.
2335 if (pmap_initialized &&
2336 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) {
2337 pmap_insert_entry(pmap, va, mpte, m);
2339 vm_page_flag_set(m, PG_MAPPED);
2343 * Increment counters
2345 ++pmap->pm_stats.resident_count;
2347 pmap->pm_stats.wired_count++;
2351 * Now validate mapping with desired protection/wiring.
2353 newpte = (pt_entry_t) (pa | pte_prot(pmap, prot) | VPTE_V);
2356 newpte |= VPTE_WIRED;
2357 if (pmap != &kernel_pmap)
2361 * If the mapping or permission bits are different from the
2362 * (now cleaned) original pte, an update is needed. We've
2363 * already downgraded or invalidated the page so all we have
2364 * to do now is update the bits.
2366 * XXX should we synchronize RO->RW changes to avoid another
2369 if ((origpte & ~(VPTE_W|VPTE_M|VPTE_A)) != newpte) {
2370 *pte = newpte | VPTE_A;
2371 if (newpte & VPTE_W)
2372 vm_page_flag_set(m, PG_WRITEABLE);
2374 KKASSERT((newpte & VPTE_MANAGED) == 0 || (m->flags & PG_MAPPED));
2375 lwkt_reltoken(&vm_token);
2376 vm_object_drop(pmap->pm_pteobj);
2380 * This code works like pmap_enter() but assumes VM_PROT_READ and not-wired.
2382 * Currently this routine may only be used on user pmaps, not kernel_pmap.
2387 pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m)
2392 vm_pindex_t ptepindex;
2395 KKASSERT(pmap != &kernel_pmap);
2397 KKASSERT(va >= VM_MIN_USER_ADDRESS && va < VM_MAX_USER_ADDRESS);
2400 * Calculate pagetable page index
2402 ptepindex = pmap_pde_pindex(va);
2404 vm_object_hold(pmap->pm_pteobj);
2405 lwkt_gettoken(&vm_token);
2409 * Get the page directory entry
2411 ptepa = pmap_pde(pmap, va);
2414 * If the page table page is mapped, we just increment
2415 * the hold count, and activate it.
2417 if (ptepa && (*ptepa & VPTE_V) != 0) {
2418 if (*ptepa & VPTE_PS)
2419 panic("pmap_enter_quick: unexpected mapping into 2MB page");
2420 if (pmap->pm_ptphint &&
2421 (pmap->pm_ptphint->pindex == ptepindex)) {
2422 mpte = pmap->pm_ptphint;
2424 mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex);
2425 pmap->pm_ptphint = mpte;
2426 vm_page_wakeup(mpte);
2431 mpte = _pmap_allocpte(pmap, ptepindex);
2433 } while (mpte == NULL);
2436 * Ok, now that the page table page has been validated, get the pte.
2437 * If the pte is already mapped undo mpte's hold_count and
2440 pte = pmap_pte(pmap, va);
2441 if (*pte & VPTE_V) {
2442 KKASSERT(mpte != NULL);
2443 pmap_unwire_pte_hold(pmap, va, mpte);
2444 pa = VM_PAGE_TO_PHYS(m);
2445 KKASSERT(((*pte ^ pa) & VPTE_FRAME) == 0);
2446 lwkt_reltoken(&vm_token);
2447 vm_object_drop(pmap->pm_pteobj);
2452 * Enter on the PV list if part of our managed memory
2454 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) {
2455 pmap_insert_entry(pmap, va, mpte, m);
2456 vm_page_flag_set(m, PG_MAPPED);
2460 * Increment counters
2462 ++pmap->pm_stats.resident_count;
2464 pa = VM_PAGE_TO_PHYS(m);
2467 * Now validate mapping with RO protection
2469 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED))
2470 *pte = (vpte_t)pa | VPTE_V | VPTE_U;
2472 *pte = (vpte_t)pa | VPTE_V | VPTE_U | VPTE_MANAGED;
2473 /*pmap_inval_add(&info, pmap, va); shouldn't be needed 0->valid */
2474 /*pmap_inval_flush(&info); don't need for vkernel */
2475 lwkt_reltoken(&vm_token);
2476 vm_object_drop(pmap->pm_pteobj);
2480 * Make a temporary mapping for a physical address. This is only intended
2481 * to be used for panic dumps.
2483 * The caller is responsible for calling smp_invltlb().
2486 pmap_kenter_temporary(vm_paddr_t pa, long i)
2488 pmap_kenter_quick(crashdumpmap + (i * PAGE_SIZE), pa);
2489 return ((void *)crashdumpmap);
2492 #define MAX_INIT_PT (96)
2495 * This routine preloads the ptes for a given object into the specified pmap.
2496 * This eliminates the blast of soft faults on process startup and
2497 * immediately after an mmap.
2501 static int pmap_object_init_pt_callback(vm_page_t p, void *data);
2504 pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, vm_prot_t prot,
2505 vm_object_t object, vm_pindex_t pindex,
2506 vm_size_t size, int limit)
2508 struct rb_vm_page_scan_info info;
2513 * We can't preinit if read access isn't set or there is no pmap
2516 if ((prot & VM_PROT_READ) == 0 || pmap == NULL || object == NULL)
2520 * We can't preinit if the pmap is not the current pmap
2522 lp = curthread->td_lwp;
2523 if (lp == NULL || pmap != vmspace_pmap(lp->lwp_vmspace))
2526 psize = x86_64_btop(size);
2528 if ((object->type != OBJT_VNODE) ||
2529 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) &&
2530 (object->resident_page_count > MAX_INIT_PT))) {
2534 if (psize + pindex > object->size) {
2535 if (object->size < pindex)
2537 psize = object->size - pindex;
2544 * Use a red-black scan to traverse the requested range and load
2545 * any valid pages found into the pmap.
2547 * We cannot safely scan the object's memq unless we are in a
2548 * critical section since interrupts can remove pages from objects.
2550 info.start_pindex = pindex;
2551 info.end_pindex = pindex + psize - 1;
2557 vm_object_hold(object);
2558 vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp,
2559 pmap_object_init_pt_callback, &info);
2560 vm_object_drop(object);
2565 pmap_object_init_pt_callback(vm_page_t p, void *data)
2567 struct rb_vm_page_scan_info *info = data;
2568 vm_pindex_t rel_index;
2570 * don't allow an madvise to blow away our really
2571 * free pages allocating pv entries.
2573 if ((info->limit & MAP_PREFAULT_MADVISE) &&
2574 vmstats.v_free_count < vmstats.v_free_reserved) {
2577 if (vm_page_busy_try(p, TRUE))
2579 if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) &&
2580 (p->flags & PG_FICTITIOUS) == 0) {
2581 if ((p->queue - p->pc) == PQ_CACHE)
2582 vm_page_deactivate(p);
2583 rel_index = p->pindex - info->start_pindex;
2584 pmap_enter_quick(info->pmap,
2585 info->addr + x86_64_ptob(rel_index), p);
2592 * Return TRUE if the pmap is in shape to trivially
2593 * pre-fault the specified address.
2595 * Returns FALSE if it would be non-trivial or if a
2596 * pte is already loaded into the slot.
2601 pmap_prefault_ok(pmap_t pmap, vm_offset_t addr)
2607 lwkt_gettoken(&vm_token);
2608 pde = pmap_pde(pmap, addr);
2609 if (pde == NULL || *pde == 0) {
2612 pte = pmap_pde_to_pte(pde, addr);
2613 ret = (*pte) ? 0 : 1;
2615 lwkt_reltoken(&vm_token);
2620 * Change the wiring attribute for a map/virtual-address pair.
2622 * The mapping must already exist in the pmap.
2623 * No other requirements.
2626 pmap_change_wiring(pmap_t pmap, vm_offset_t va, boolean_t wired)
2633 lwkt_gettoken(&vm_token);
2634 pte = pmap_pte(pmap, va);
2636 if (wired && !pmap_pte_w(pte))
2637 pmap->pm_stats.wired_count++;
2638 else if (!wired && pmap_pte_w(pte))
2639 pmap->pm_stats.wired_count--;
2642 * Wiring is not a hardware characteristic so there is no need to
2643 * invalidate TLB. However, in an SMP environment we must use
2644 * a locked bus cycle to update the pte (if we are not using
2645 * the pmap_inval_*() API that is)... it's ok to do this for simple
2649 atomic_set_long(pte, VPTE_WIRED);
2651 atomic_clear_long(pte, VPTE_WIRED);
2652 lwkt_reltoken(&vm_token);
2656 * Copy the range specified by src_addr/len
2657 * from the source map to the range dst_addr/len
2658 * in the destination map.
2660 * This routine is only advisory and need not do anything.
2663 pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr,
2664 vm_size_t len, vm_offset_t src_addr)
2667 * XXX BUGGY. Amoung other things srcmpte is assumed to remain
2668 * valid through blocking calls, and that's just not going to
2679 * Zero the specified physical page.
2681 * This function may be called from an interrupt and no locking is
2685 pmap_zero_page(vm_paddr_t phys)
2687 vm_offset_t va = PHYS_TO_DMAP(phys);
2689 bzero((void *)va, PAGE_SIZE);
2693 * pmap_page_assertzero:
2695 * Assert that a page is empty, panic if it isn't.
2698 pmap_page_assertzero(vm_paddr_t phys)
2703 vm_offset_t virt = PHYS_TO_DMAP(phys);
2705 for (i = 0; i < PAGE_SIZE; i += sizeof(int)) {
2706 if (*(int *)((char *)virt + i) != 0) {
2707 panic("pmap_page_assertzero() @ %p not zero!\n",
2717 * Zero part of a physical page by mapping it into memory and clearing
2718 * its contents with bzero.
2720 * off and size may not cover an area beyond a single hardware page.
2723 pmap_zero_page_area(vm_paddr_t phys, int off, int size)
2726 vm_offset_t virt = PHYS_TO_DMAP(phys);
2727 bzero((char *)virt + off, size);
2734 * Copy the physical page from the source PA to the target PA.
2735 * This function may be called from an interrupt. No locking
2739 pmap_copy_page(vm_paddr_t src, vm_paddr_t dst)
2741 vm_offset_t src_virt, dst_virt;
2744 src_virt = PHYS_TO_DMAP(src);
2745 dst_virt = PHYS_TO_DMAP(dst);
2746 bcopy((void *)src_virt, (void *)dst_virt, PAGE_SIZE);
2751 * pmap_copy_page_frag:
2753 * Copy the physical page from the source PA to the target PA.
2754 * This function may be called from an interrupt. No locking
2758 pmap_copy_page_frag(vm_paddr_t src, vm_paddr_t dst, size_t bytes)
2760 vm_offset_t src_virt, dst_virt;
2763 src_virt = PHYS_TO_DMAP(src);
2764 dst_virt = PHYS_TO_DMAP(dst);
2765 bcopy((char *)src_virt + (src & PAGE_MASK),
2766 (char *)dst_virt + (dst & PAGE_MASK),
2772 * Returns true if the pmap's pv is one of the first 16 pvs linked to
2773 * from this page. This count may be changed upwards or downwards
2774 * in the future; it is only necessary that true be returned for a small
2775 * subset of pmaps for proper page aging.
2777 * No other requirements.
2780 pmap_page_exists_quick(pmap_t pmap, vm_page_t m)
2785 if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
2789 lwkt_gettoken(&vm_token);
2791 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
2792 if (pv->pv_pmap == pmap) {
2793 lwkt_reltoken(&vm_token);
2801 lwkt_reltoken(&vm_token);
2807 * Remove all pages from specified address space this aids process
2808 * exit speeds. Also, this code is special cased for current
2809 * process only, but can have the more generic (and slightly slower)
2810 * mode enabled. This is much faster than pmap_remove in the case
2811 * of running down an entire address space.
2813 * No other requirements.
2816 pmap_remove_pages(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
2818 pt_entry_t *pte, tpte;
2821 int save_generation;
2823 if (pmap->pm_pteobj)
2824 vm_object_hold(pmap->pm_pteobj);
2825 lwkt_gettoken(&vm_token);
2827 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) {
2828 if (pv->pv_va >= eva || pv->pv_va < sva) {
2829 npv = TAILQ_NEXT(pv, pv_plist);
2833 KKASSERT(pmap == pv->pv_pmap);
2835 pte = pmap_pte(pmap, pv->pv_va);
2838 * We cannot remove wired pages from a process' mapping
2841 if (*pte & VPTE_WIRED) {
2842 npv = TAILQ_NEXT(pv, pv_plist);
2845 tpte = pmap_inval_loadandclear(pte, pmap, pv->pv_va);
2847 m = PHYS_TO_VM_PAGE(tpte & VPTE_FRAME);
2849 KASSERT(m < &vm_page_array[vm_page_array_size],
2850 ("pmap_remove_pages: bad tpte %lx", tpte));
2852 KKASSERT(pmap->pm_stats.resident_count > 0);
2853 --pmap->pm_stats.resident_count;
2856 * Update the vm_page_t clean and reference bits.
2858 if (tpte & VPTE_M) {
2862 npv = TAILQ_NEXT(pv, pv_plist);
2863 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist);
2864 save_generation = ++pmap->pm_generation;
2866 m->md.pv_list_count--;
2867 atomic_add_int(&m->object->agg_pv_list_count, -1);
2868 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
2869 if (TAILQ_EMPTY(&m->md.pv_list))
2870 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
2872 pmap_unuse_pt(pmap, pv->pv_va, pv->pv_ptem);
2876 * Restart the scan if we blocked during the unuse or free
2877 * calls and other removals were made.
2879 if (save_generation != pmap->pm_generation) {
2880 kprintf("Warning: pmap_remove_pages race-A avoided\n");
2881 npv = TAILQ_FIRST(&pmap->pm_pvlist);
2884 lwkt_reltoken(&vm_token);
2885 if (pmap->pm_pteobj)
2886 vm_object_drop(pmap->pm_pteobj);
2890 * pmap_testbit tests bits in active mappings of a VM page.
2893 pmap_testbit(vm_page_t m, int bit)
2898 if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
2901 if (TAILQ_FIRST(&m->md.pv_list) == NULL)
2906 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
2908 * if the bit being tested is the modified bit, then
2909 * mark clean_map and ptes as never
2912 if (bit & (VPTE_A|VPTE_M)) {
2913 if (!pmap_track_modified(pv->pv_pmap, pv->pv_va))
2917 #if defined(PMAP_DIAGNOSTIC)
2918 if (pv->pv_pmap == NULL) {
2919 kprintf("Null pmap (tb) at va: 0x%lx\n", pv->pv_va);
2923 pte = pmap_pte(pv->pv_pmap, pv->pv_va);
2934 * This routine is used to clear bits in ptes. Certain bits require special
2935 * handling, in particular (on virtual kernels) the VPTE_M (modify) bit.
2937 * This routine is only called with certain VPTE_* bit combinations.
2939 static __inline void
2940 pmap_clearbit(vm_page_t m, int bit)
2946 if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
2952 * Loop over all current mappings setting/clearing as appropos If
2953 * setting RO do we need to clear the VAC?
2955 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) {
2957 * don't write protect pager mappings
2959 if (bit == VPTE_W) {
2960 if (!pmap_track_modified(pv->pv_pmap, pv->pv_va))
2964 #if defined(PMAP_DIAGNOSTIC)
2965 if (pv->pv_pmap == NULL) {
2966 kprintf("Null pmap (cb) at va: 0x%lx\n", pv->pv_va);
2972 * Careful here. We can use a locked bus instruction to
2973 * clear VPTE_A or VPTE_M safely but we need to synchronize
2974 * with the target cpus when we mess with VPTE_W.
2976 * On virtual kernels we must force a new fault-on-write
2977 * in the real kernel if we clear the Modify bit ourselves,
2978 * otherwise the real kernel will not get a new fault and
2979 * will never set our Modify bit again.
2981 pte = pmap_pte(pv->pv_pmap, pv->pv_va);
2983 if (bit == VPTE_W) {
2985 * We must also clear VPTE_M when clearing
2988 pbits = pmap_clean_pte(pte, pv->pv_pmap,
2992 } else if (bit == VPTE_M) {
2994 * We do not have to make the page read-only
2995 * when clearing the Modify bit. The real
2996 * kernel will make the real PTE read-only
2997 * or otherwise detect the write and set
2998 * our VPTE_M again simply by us invalidating
2999 * the real kernel VA for the pmap (as we did
3000 * above). This allows the real kernel to
3001 * handle the write fault without forwarding
3004 atomic_clear_long(pte, VPTE_M);
3005 } else if ((bit & (VPTE_W|VPTE_M)) == (VPTE_W|VPTE_M)) {
3007 * We've been asked to clear W & M, I guess
3008 * the caller doesn't want us to update
3009 * the dirty status of the VM page.
3011 pmap_clean_pte(pte, pv->pv_pmap, pv->pv_va);
3014 * We've been asked to clear bits that do
3015 * not interact with hardware.
3017 atomic_clear_long(pte, bit);
3025 * Lower the permission for all mappings to a given page.
3027 * No other requirements.
3030 pmap_page_protect(vm_page_t m, vm_prot_t prot)
3032 /* JG NX support? */
3033 if ((prot & VM_PROT_WRITE) == 0) {
3034 lwkt_gettoken(&vm_token);
3035 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) {
3036 pmap_clearbit(m, VPTE_W);
3037 vm_page_flag_clear(m, PG_WRITEABLE);
3041 lwkt_reltoken(&vm_token);
3046 pmap_phys_address(vm_pindex_t ppn)
3048 return (x86_64_ptob(ppn));
3052 * Return a count of reference bits for a page, clearing those bits.
3053 * It is not necessary for every reference bit to be cleared, but it
3054 * is necessary that 0 only be returned when there are truly no
3055 * reference bits set.
3057 * XXX: The exact number of bits to check and clear is a matter that
3058 * should be tested and standardized at some point in the future for
3059 * optimal aging of shared pages.
3061 * No other requirements.
3064 pmap_ts_referenced(vm_page_t m)
3066 pv_entry_t pv, pvf, pvn;
3070 if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
3074 lwkt_gettoken(&vm_token);
3076 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
3081 pvn = TAILQ_NEXT(pv, pv_list);
3083 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
3085 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
3087 if (!pmap_track_modified(pv->pv_pmap, pv->pv_va))
3090 pte = pmap_pte(pv->pv_pmap, pv->pv_va);
3092 if (pte && (*pte & VPTE_A)) {
3094 atomic_clear_long(pte, VPTE_A);
3096 atomic_clear_long_nonlocked(pte, VPTE_A);
3103 } while ((pv = pvn) != NULL && pv != pvf);
3105 lwkt_reltoken(&vm_token);
3112 * Return whether or not the specified physical page was modified
3113 * in any physical maps.
3115 * No other requirements.
3118 pmap_is_modified(vm_page_t m)
3122 lwkt_gettoken(&vm_token);
3123 res = pmap_testbit(m, VPTE_M);
3124 lwkt_reltoken(&vm_token);
3129 * Clear the modify bits on the specified physical page.
3131 * No other requirements.
3134 pmap_clear_modify(vm_page_t m)
3136 lwkt_gettoken(&vm_token);
3137 pmap_clearbit(m, VPTE_M);
3138 lwkt_reltoken(&vm_token);
3142 * Clear the reference bit on the specified physical page.
3144 * No other requirements.
3147 pmap_clear_reference(vm_page_t m)
3149 lwkt_gettoken(&vm_token);
3150 pmap_clearbit(m, VPTE_A);
3151 lwkt_reltoken(&vm_token);
3155 * Miscellaneous support routines follow
3159 i386_protection_init(void)
3163 kp = protection_codes;
3164 for (prot = 0; prot < 8; prot++) {
3165 if (prot & VM_PROT_READ)
3167 if (prot & VM_PROT_WRITE)
3169 if (prot & VM_PROT_EXECUTE)
3176 * Perform the pmap work for mincore
3178 * No other requirements.
3181 pmap_mincore(pmap_t pmap, vm_offset_t addr)
3183 pt_entry_t *ptep, pte;
3187 lwkt_gettoken(&vm_token);
3188 ptep = pmap_pte(pmap, addr);
3190 if (ptep && (pte = *ptep) != 0) {
3193 val = MINCORE_INCORE;
3194 if ((pte & VPTE_MANAGED) == 0)
3197 pa = pte & VPTE_FRAME;
3199 m = PHYS_TO_VM_PAGE(pa);
3205 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER;
3207 * Modified by someone
3209 else if (m->dirty || pmap_is_modified(m))
3210 val |= MINCORE_MODIFIED_OTHER;
3215 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER;
3218 * Referenced by someone
3220 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) {
3221 val |= MINCORE_REFERENCED_OTHER;
3222 vm_page_flag_set(m, PG_REFERENCED);
3226 lwkt_reltoken(&vm_token);
3231 * Replace p->p_vmspace with a new one. If adjrefs is non-zero the new
3232 * vmspace will be ref'd and the old one will be deref'd.
3234 * Caller must hold vmspace->vm_map.token for oldvm and newvm
3237 pmap_replacevm(struct proc *p, struct vmspace *newvm, int adjrefs)
3239 struct vmspace *oldvm;
3243 oldvm = p->p_vmspace;
3244 if (oldvm != newvm) {
3245 p->p_vmspace = newvm;
3246 KKASSERT(p->p_nthreads == 1);
3247 lp = RB_ROOT(&p->p_lwp_tree);
3248 pmap_setlwpvm(lp, newvm);
3250 sysref_get(&newvm->vm_sysref);
3251 sysref_put(&oldvm->vm_sysref);
3258 * Set the vmspace for a LWP. The vmspace is almost universally set the
3259 * same as the process vmspace, but virtual kernels need to swap out contexts
3260 * on a per-lwp basis.
3263 pmap_setlwpvm(struct lwp *lp, struct vmspace *newvm)
3265 struct vmspace *oldvm;
3269 oldvm = lp->lwp_vmspace;
3271 if (oldvm != newvm) {
3272 lp->lwp_vmspace = newvm;
3273 if (curthread->td_lwp == lp) {
3274 pmap = vmspace_pmap(newvm);
3276 atomic_set_cpumask(&pmap->pm_active, CPUMASK(mycpu->gd_cpuid));
3278 pmap->pm_active |= 1;
3280 #if defined(SWTCH_OPTIM_STATS)
3283 pmap = vmspace_pmap(oldvm);
3285 atomic_clear_cpumask(&pmap->pm_active,
3286 CPUMASK(mycpu->gd_cpuid));
3288 pmap->pm_active &= ~(cpumask_t)1;
3296 pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size)
3299 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) {
3303 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1);
3308 * Used by kmalloc/kfree, page already exists at va
3311 pmap_kvtom(vm_offset_t va)
3315 KKASSERT(va >= KvaStart && va < KvaEnd);
3317 return(PHYS_TO_VM_PAGE(*ptep & PG_FRAME));