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.
52 * In most cases the vm_token must be held when manipulating a user pmap
53 * or elements within a vm_page, and the kvm_token must be held when
54 * manipulating the kernel pmap. Operations on user pmaps may require
55 * additional synchronization.
57 * In some cases the caller may hold the required tokens to prevent pmap
58 * functions from blocking on those same tokens. This typically only works
59 * for lookup-style operations.
65 #include "opt_msgbuf.h"
67 #include <sys/param.h>
68 #include <sys/systm.h>
69 #include <sys/kernel.h>
71 #include <sys/msgbuf.h>
72 #include <sys/vmmeter.h>
74 #include <sys/vmspace.h>
77 #include <vm/vm_param.h>
78 #include <sys/sysctl.h>
80 #include <vm/vm_kern.h>
81 #include <vm/vm_page.h>
82 #include <vm/vm_map.h>
83 #include <vm/vm_object.h>
84 #include <vm/vm_extern.h>
85 #include <vm/vm_pageout.h>
86 #include <vm/vm_pager.h>
87 #include <vm/vm_zone.h>
90 #include <sys/thread2.h>
91 #include <sys/sysref2.h>
93 #include <machine/cputypes.h>
94 #include <machine/md_var.h>
95 #include <machine/specialreg.h>
96 #include <machine/smp.h>
97 #include <machine/globaldata.h>
98 #include <machine/pmap.h>
99 #include <machine/pmap_inval.h>
107 #define PMAP_KEEP_PDIRS
108 #ifndef PMAP_SHPGPERPROC
109 #define PMAP_SHPGPERPROC 200
112 #if defined(DIAGNOSTIC)
113 #define PMAP_DIAGNOSTIC
118 #if !defined(PMAP_DIAGNOSTIC)
119 #define PMAP_INLINE __inline
125 * Get PDEs and PTEs for user/kernel address space
127 static pd_entry_t
*pmap_pde(pmap_t pmap
, vm_offset_t va
);
128 #define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT])
130 #define pmap_pde_v(pte) ((*(pd_entry_t *)pte & VPTE_V) != 0)
131 #define pmap_pte_w(pte) ((*(pt_entry_t *)pte & VPTE_WIRED) != 0)
132 #define pmap_pte_m(pte) ((*(pt_entry_t *)pte & VPTE_M) != 0)
133 #define pmap_pte_u(pte) ((*(pt_entry_t *)pte & VPTE_A) != 0)
134 #define pmap_pte_v(pte) ((*(pt_entry_t *)pte & VPTE_V) != 0)
137 * Given a map and a machine independent protection code,
138 * convert to a vax protection code.
140 #define pte_prot(m, p) \
141 (protection_codes[p & (VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE)])
142 static int protection_codes
[8];
144 struct pmap kernel_pmap
;
145 static TAILQ_HEAD(,pmap
) pmap_list
= TAILQ_HEAD_INITIALIZER(pmap_list
);
147 static boolean_t pmap_initialized
= FALSE
; /* Has pmap_init completed? */
149 static vm_object_t kptobj
;
153 static uint64_t KPDphys
; /* phys addr of kernel level 2 */
154 uint64_t KPDPphys
; /* phys addr of kernel level 3 */
155 uint64_t KPML4phys
; /* phys addr of kernel level 4 */
159 * Data for the pv entry allocation mechanism
161 static vm_zone_t pvzone
;
162 static struct vm_zone pvzone_store
;
163 static struct vm_object pvzone_obj
;
164 static int pv_entry_count
=0, pv_entry_max
=0, pv_entry_high_water
=0;
165 static int pmap_pagedaemon_waken
= 0;
166 static struct pv_entry
*pvinit
;
169 * All those kernel PT submaps that BSD is so fond of
171 pt_entry_t
*CMAP1
= 0, *ptmmap
;
173 static pt_entry_t
*msgbufmap
;
177 static PMAP_INLINE
void free_pv_entry (pv_entry_t pv
);
178 static pv_entry_t
get_pv_entry (void);
179 static void i386_protection_init (void);
180 static __inline
void pmap_clearbit (vm_page_t m
, int bit
);
182 static void pmap_remove_all (vm_page_t m
);
183 static int pmap_remove_pte (struct pmap
*pmap
, pt_entry_t
*ptq
,
185 static void pmap_remove_page (struct pmap
*pmap
, vm_offset_t va
);
186 static int pmap_remove_entry (struct pmap
*pmap
, vm_page_t m
,
188 static boolean_t
pmap_testbit (vm_page_t m
, int bit
);
189 static void pmap_insert_entry (pmap_t pmap
, vm_offset_t va
,
190 vm_page_t mpte
, vm_page_t m
);
192 static vm_page_t
pmap_allocpte (pmap_t pmap
, vm_offset_t va
);
194 static int pmap_release_free_page (pmap_t pmap
, vm_page_t p
);
195 static vm_page_t
_pmap_allocpte (pmap_t pmap
, vm_pindex_t ptepindex
);
197 static pt_entry_t
* pmap_pte_quick (pmap_t pmap
, vm_offset_t va
);
199 static vm_page_t
pmap_page_lookup (vm_object_t object
, vm_pindex_t pindex
);
200 static int pmap_unuse_pt (pmap_t
, vm_offset_t
, vm_page_t
);
205 * Super fast pmap_pte routine best used when scanning the pv lists.
206 * This eliminates many course-grained invltlb calls. Note that many of
207 * the pv list scans are across different pmaps and it is very wasteful
208 * to do an entire invltlb when checking a single mapping.
210 * Should only be called while in a critical section.
213 static __inline pt_entry_t
*pmap_pte(pmap_t pmap
, vm_offset_t va
);
216 pmap_pte_quick(pmap_t pmap
, vm_offset_t va
)
218 return pmap_pte(pmap
, va
);
222 /* Return a non-clipped PD index for a given VA */
223 static __inline vm_pindex_t
224 pmap_pde_pindex(vm_offset_t va
)
226 return va
>> PDRSHIFT
;
229 /* Return various clipped indexes for a given VA */
230 static __inline vm_pindex_t
231 pmap_pte_index(vm_offset_t va
)
234 return ((va
>> PAGE_SHIFT
) & ((1ul << NPTEPGSHIFT
) - 1));
237 static __inline vm_pindex_t
238 pmap_pde_index(vm_offset_t va
)
241 return ((va
>> PDRSHIFT
) & ((1ul << NPDEPGSHIFT
) - 1));
244 static __inline vm_pindex_t
245 pmap_pdpe_index(vm_offset_t va
)
248 return ((va
>> PDPSHIFT
) & ((1ul << NPDPEPGSHIFT
) - 1));
251 static __inline vm_pindex_t
252 pmap_pml4e_index(vm_offset_t va
)
255 return ((va
>> PML4SHIFT
) & ((1ul << NPML4EPGSHIFT
) - 1));
258 /* Return a pointer to the PML4 slot that corresponds to a VA */
259 static __inline pml4_entry_t
*
260 pmap_pml4e(pmap_t pmap
, vm_offset_t va
)
263 return (&pmap
->pm_pml4
[pmap_pml4e_index(va
)]);
266 /* Return a pointer to the PDP slot that corresponds to a VA */
267 static __inline pdp_entry_t
*
268 pmap_pml4e_to_pdpe(pml4_entry_t
*pml4e
, vm_offset_t va
)
272 pdpe
= (pdp_entry_t
*)PHYS_TO_DMAP(*pml4e
& VPTE_FRAME
);
273 return (&pdpe
[pmap_pdpe_index(va
)]);
276 /* Return a pointer to the PDP slot that corresponds to a VA */
277 static __inline pdp_entry_t
*
278 pmap_pdpe(pmap_t pmap
, vm_offset_t va
)
282 pml4e
= pmap_pml4e(pmap
, va
);
283 if ((*pml4e
& VPTE_V
) == 0)
285 return (pmap_pml4e_to_pdpe(pml4e
, va
));
288 /* Return a pointer to the PD slot that corresponds to a VA */
289 static __inline pd_entry_t
*
290 pmap_pdpe_to_pde(pdp_entry_t
*pdpe
, vm_offset_t va
)
294 pde
= (pd_entry_t
*)PHYS_TO_DMAP(*pdpe
& VPTE_FRAME
);
295 return (&pde
[pmap_pde_index(va
)]);
298 /* Return a pointer to the PD slot that corresponds to a VA */
299 static __inline pd_entry_t
*
300 pmap_pde(pmap_t pmap
, vm_offset_t va
)
304 pdpe
= pmap_pdpe(pmap
, va
);
305 if (pdpe
== NULL
|| (*pdpe
& VPTE_V
) == 0)
307 return (pmap_pdpe_to_pde(pdpe
, va
));
310 /* Return a pointer to the PT slot that corresponds to a VA */
311 static __inline pt_entry_t
*
312 pmap_pde_to_pte(pd_entry_t
*pde
, vm_offset_t va
)
316 pte
= (pt_entry_t
*)PHYS_TO_DMAP(*pde
& VPTE_FRAME
);
317 return (&pte
[pmap_pte_index(va
)]);
320 /* Return a pointer to the PT slot that corresponds to a VA */
321 static __inline pt_entry_t
*
322 pmap_pte(pmap_t pmap
, vm_offset_t va
)
326 pde
= pmap_pde(pmap
, va
);
327 if (pde
== NULL
|| (*pde
& VPTE_V
) == 0)
329 if ((*pde
& VPTE_PS
) != 0) /* compat with i386 pmap_pte() */
330 return ((pt_entry_t
*)pde
);
331 return (pmap_pde_to_pte(pde
, va
));
336 PMAP_INLINE pt_entry_t
*
337 vtopte(vm_offset_t va
)
339 uint64_t mask
= ((1ul << (NPTEPGSHIFT
+ NPDEPGSHIFT
+ NPDPEPGSHIFT
+ NPML4EPGSHIFT
)) - 1);
341 return (PTmap
+ ((va
>> PAGE_SHIFT
) & mask
));
344 static __inline pd_entry_t
*
345 vtopde(vm_offset_t va
)
347 uint64_t mask
= ((1ul << (NPDEPGSHIFT
+ NPDPEPGSHIFT
+ NPML4EPGSHIFT
)) - 1);
349 return (PDmap
+ ((va
>> PDRSHIFT
) & mask
));
352 static PMAP_INLINE pt_entry_t
*
353 vtopte(vm_offset_t va
)
356 x
= pmap_pte(&kernel_pmap
, va
);
361 static __inline pd_entry_t
*
362 vtopde(vm_offset_t va
)
365 x
= pmap_pde(&kernel_pmap
, va
);
372 allocpages(vm_paddr_t
*firstaddr
, int n
)
378 bzero((void *)ret
, n
* PAGE_SIZE
);
380 *firstaddr
+= n
* PAGE_SIZE
;
385 create_pagetables(vm_paddr_t
*firstaddr
, int64_t ptov_offset
)
388 pml4_entry_t
*KPML4virt
;
389 pdp_entry_t
*KPDPvirt
;
392 int kpml4i
= pmap_pml4e_index(ptov_offset
);
393 int kpdpi
= pmap_pdpe_index(ptov_offset
);
396 * Calculate NKPT - number of kernel page tables. We have to
397 * accomodoate prealloction of the vm_page_array, dump bitmap,
398 * MSGBUF_SIZE, and other stuff. Be generous.
400 * Maxmem is in pages.
402 nkpt
= (Maxmem
* (sizeof(struct vm_page
) * 2) + MSGBUF_SIZE
) / NBPDR
;
407 KPML4phys
= allocpages(firstaddr
, 1);
408 KPDPphys
= allocpages(firstaddr
, NKPML4E
);
409 KPDphys
= allocpages(firstaddr
, NKPDPE
);
410 KPTphys
= allocpages(firstaddr
, nkpt
);
412 KPML4virt
= (pml4_entry_t
*)PHYS_TO_DMAP(KPML4phys
);
413 KPDPvirt
= (pdp_entry_t
*)PHYS_TO_DMAP(KPDPphys
);
414 KPDvirt
= (pd_entry_t
*)PHYS_TO_DMAP(KPDphys
);
415 KPTvirt
= (pt_entry_t
*)PHYS_TO_DMAP(KPTphys
);
417 bzero(KPML4virt
, 1 * PAGE_SIZE
);
418 bzero(KPDPvirt
, NKPML4E
* PAGE_SIZE
);
419 bzero(KPDvirt
, NKPDPE
* PAGE_SIZE
);
420 bzero(KPTvirt
, nkpt
* PAGE_SIZE
);
422 /* Now map the page tables at their location within PTmap */
423 for (i
= 0; i
< nkpt
; i
++) {
424 KPDvirt
[i
] = KPTphys
+ (i
<< PAGE_SHIFT
);
425 KPDvirt
[i
] |= VPTE_R
| VPTE_W
| VPTE_V
;
428 /* And connect up the PD to the PDP */
429 for (i
= 0; i
< NKPDPE
; i
++) {
430 KPDPvirt
[i
+ kpdpi
] = KPDphys
+ (i
<< PAGE_SHIFT
);
431 KPDPvirt
[i
+ kpdpi
] |= VPTE_R
| VPTE_W
| VPTE_V
;
434 /* And recursively map PML4 to itself in order to get PTmap */
435 KPML4virt
[PML4PML4I
] = KPML4phys
;
436 KPML4virt
[PML4PML4I
] |= VPTE_R
| VPTE_W
| VPTE_V
;
438 /* Connect the KVA slot up to the PML4 */
439 KPML4virt
[kpml4i
] = KPDPphys
;
440 KPML4virt
[kpml4i
] |= VPTE_R
| VPTE_W
| VPTE_V
;
444 * Bootstrap the system enough to run with virtual memory.
446 * On the i386 this is called after mapping has already been enabled
447 * and just syncs the pmap module with what has already been done.
448 * [We can't call it easily with mapping off since the kernel is not
449 * mapped with PA == VA, hence we would have to relocate every address
450 * from the linked base (virtual) address "KERNBASE" to the actual
451 * (physical) address starting relative to 0]
454 pmap_bootstrap(vm_paddr_t
*firstaddr
, int64_t ptov_offset
)
460 * Create an initial set of page tables to run the kernel in.
462 create_pagetables(firstaddr
, ptov_offset
);
464 virtual_start
= KvaStart
+ *firstaddr
;
465 virtual_end
= KvaEnd
;
468 * Initialize protection array.
470 i386_protection_init();
473 * The kernel's pmap is statically allocated so we don't have to use
474 * pmap_create, which is unlikely to work correctly at this part of
475 * the boot sequence (XXX and which no longer exists).
477 kernel_pmap
.pm_pml4
= (pml4_entry_t
*)PHYS_TO_DMAP(KPML4phys
);
478 kernel_pmap
.pm_count
= 1;
479 kernel_pmap
.pm_active
= (cpumask_t
)-1; /* don't allow deactivation */
480 TAILQ_INIT(&kernel_pmap
.pm_pvlist
);
483 * Reserve some special page table entries/VA space for temporary
486 #define SYSMAP(c, p, v, n) \
487 v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n);
490 pte
= pmap_pte(&kernel_pmap
, va
);
493 * CMAP1/CMAP2 are used for zeroing and copying pages.
495 SYSMAP(caddr_t
, CMAP1
, CADDR1
, 1)
501 SYSMAP(caddr_t
, pt_crashdumpmap
, crashdumpmap
, MAXDUMPPGS
);
505 * ptvmmap is used for reading arbitrary physical pages via
508 SYSMAP(caddr_t
, ptmmap
, ptvmmap
, 1)
511 * msgbufp is used to map the system message buffer.
512 * XXX msgbufmap is not used.
514 SYSMAP(struct msgbuf
*, msgbufmap
, msgbufp
,
515 atop(round_page(MSGBUF_SIZE
)))
525 * Initialize the pmap module.
526 * Called by vm_init, to initialize any structures that the pmap
527 * system needs to map virtual memory.
528 * pmap_init has been enhanced to support in a fairly consistant
529 * way, discontiguous physical memory.
538 * object for kernel page table pages
540 /* JG I think the number can be arbitrary */
541 kptobj
= vm_object_allocate(OBJT_DEFAULT
, 5);
544 * Allocate memory for random pmap data structures. Includes the
548 for(i
= 0; i
< vm_page_array_size
; i
++) {
551 m
= &vm_page_array
[i
];
552 TAILQ_INIT(&m
->md
.pv_list
);
553 m
->md
.pv_list_count
= 0;
557 * init the pv free list
559 initial_pvs
= vm_page_array_size
;
560 if (initial_pvs
< MINPV
)
562 pvzone
= &pvzone_store
;
563 pvinit
= (struct pv_entry
*) kmem_alloc(&kernel_map
,
564 initial_pvs
* sizeof (struct pv_entry
));
565 zbootinit(pvzone
, "PV ENTRY", sizeof (struct pv_entry
), pvinit
,
569 * Now it is safe to enable pv_table recording.
571 pmap_initialized
= TRUE
;
575 * Initialize the address space (zone) for the pv_entries. Set a
576 * high water mark so that the system can recover from excessive
577 * numbers of pv entries.
582 int shpgperproc
= PMAP_SHPGPERPROC
;
584 TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc
);
585 pv_entry_max
= shpgperproc
* maxproc
+ vm_page_array_size
;
586 TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max
);
587 pv_entry_high_water
= 9 * (pv_entry_max
/ 10);
588 zinitna(pvzone
, &pvzone_obj
, NULL
, 0, pv_entry_max
, ZONE_INTERRUPT
, 1);
592 /***************************************************
593 * Low level helper routines.....
594 ***************************************************/
597 * The modification bit is not tracked for any pages in this range. XXX
598 * such pages in this maps should always use pmap_k*() functions and not
601 * XXX User and kernel address spaces are independant for virtual kernels,
602 * this function only applies to the kernel pmap.
605 pmap_track_modified(pmap_t pmap
, vm_offset_t va
)
607 if (pmap
!= &kernel_pmap
)
609 if ((va
< clean_sva
) || (va
>= clean_eva
))
616 * Extract the physical page address associated with the map/VA pair.
621 pmap_extract(pmap_t pmap
, vm_offset_t va
)
625 pd_entry_t pde
, *pdep
;
627 lwkt_gettoken(&vm_token
);
629 pdep
= pmap_pde(pmap
, va
);
633 if ((pde
& VPTE_PS
) != 0) {
635 rtval
= (pde
& PG_PS_FRAME
) | (va
& PDRMASK
);
637 pte
= pmap_pde_to_pte(pdep
, va
);
638 rtval
= (*pte
& VPTE_FRAME
) | (va
& PAGE_MASK
);
642 lwkt_reltoken(&vm_token
);
647 * Routine: pmap_kextract
649 * Extract the physical page address associated
650 * kernel virtual address.
653 pmap_kextract(vm_offset_t va
)
658 KKASSERT(va
>= KvaStart
&& va
< KvaEnd
);
661 * The DMAP region is not included in [KvaStart, KvaEnd)
664 if (va
>= DMAP_MIN_ADDRESS
&& va
< DMAP_MAX_ADDRESS
) {
665 pa
= DMAP_TO_PHYS(va
);
671 pa
= (pde
& PG_PS_FRAME
) | (va
& PDRMASK
);
674 * Beware of a concurrent promotion that changes the
675 * PDE at this point! For example, vtopte() must not
676 * be used to access the PTE because it would use the
677 * new PDE. It is, however, safe to use the old PDE
678 * because the page table page is preserved by the
681 pa
= *pmap_pde_to_pte(&pde
, va
);
682 pa
= (pa
& VPTE_FRAME
) | (va
& PAGE_MASK
);
690 /***************************************************
691 * Low level mapping routines.....
692 ***************************************************/
695 * Enter a mapping into kernel_pmap. Mappings created in this fashion
696 * are not managed. Mappings must be immediately accessible on all cpus.
698 * Call pmap_inval_pte() to invalidate the virtual pte and clean out the
699 * real pmap and handle related races before storing the new vpte.
702 pmap_kenter(vm_offset_t va
, vm_paddr_t pa
)
707 KKASSERT(va
>= KvaStart
&& va
< KvaEnd
);
708 npte
= pa
| VPTE_R
| VPTE_W
| VPTE_V
;
711 pmap_inval_pte(pte
, &kernel_pmap
, va
);
716 * Enter an unmanaged KVA mapping for the private use of the current
717 * cpu only. pmap_kenter_sync() may be called to make the mapping usable
720 * It is illegal for the mapping to be accessed by other cpus unleess
721 * pmap_kenter_sync*() is called.
724 pmap_kenter_quick(vm_offset_t va
, vm_paddr_t pa
)
729 KKASSERT(va
>= KvaStart
&& va
< KvaEnd
);
731 npte
= (vpte_t
)pa
| VPTE_R
| VPTE_W
| VPTE_V
;
734 pmap_inval_pte_quick(pte
, &kernel_pmap
, va
);
736 //cpu_invlpg((void *)va);
740 * Synchronize a kvm mapping originally made for the private use on
741 * some other cpu so it can be used on all cpus.
743 * XXX add MADV_RESYNC to improve performance.
746 pmap_kenter_sync(vm_offset_t va
)
748 madvise((void *)va
, PAGE_SIZE
, MADV_INVAL
);
752 * Synchronize a kvm mapping originally made for the private use on
753 * some other cpu so it can be used on our cpu. Turns out to be the
754 * same madvise() call, because we have to sync the real pmaps anyway.
756 * XXX add MADV_RESYNC to improve performance.
759 pmap_kenter_sync_quick(vm_offset_t va
)
761 madvise((void *)va
, PAGE_SIZE
, MADV_INVAL
);
765 * Remove an unmanaged mapping created with pmap_kenter*().
768 pmap_kremove(vm_offset_t va
)
772 KKASSERT(va
>= KvaStart
&& va
< KvaEnd
);
776 pmap_inval_pte(pte
, &kernel_pmap
, va
);
781 * Remove an unmanaged mapping created with pmap_kenter*() but synchronize
782 * only with this cpu.
784 * Unfortunately because we optimize new entries by testing VPTE_V later
785 * on, we actually still have to synchronize with all the cpus. XXX maybe
786 * store a junk value and test against 0 in the other places instead?
789 pmap_kremove_quick(vm_offset_t va
)
793 KKASSERT(va
>= KvaStart
&& va
< KvaEnd
);
797 pmap_inval_pte(pte
, &kernel_pmap
, va
); /* NOT _quick */
802 * Used to map a range of physical addresses into kernel
803 * virtual address space.
805 * For now, VM is already on, we only need to map the
809 pmap_map(vm_offset_t
*virtp
, vm_paddr_t start
, vm_paddr_t end
, int prot
)
811 return PHYS_TO_DMAP(start
);
816 * Map a set of unmanaged VM pages into KVM.
819 pmap_qenter(vm_offset_t va
, vm_page_t
*m
, int count
)
823 end_va
= va
+ count
* PAGE_SIZE
;
824 KKASSERT(va
>= KvaStart
&& end_va
< KvaEnd
);
826 while (va
< end_va
) {
831 pmap_inval_pte(pte
, &kernel_pmap
, va
);
832 *pte
= VM_PAGE_TO_PHYS(*m
) | VPTE_R
| VPTE_W
| VPTE_V
;
839 * Undo the effects of pmap_qenter*().
842 pmap_qremove(vm_offset_t va
, int count
)
846 end_va
= va
+ count
* PAGE_SIZE
;
847 KKASSERT(va
>= KvaStart
&& end_va
< KvaEnd
);
849 while (va
< end_va
) {
854 pmap_inval_pte(pte
, &kernel_pmap
, va
);
861 * This routine works like vm_page_lookup() but also blocks as long as the
862 * page is busy. This routine does not busy the page it returns.
864 * Unless the caller is managing objects whos pages are in a known state,
865 * the call should be made with a critical section held so the page's object
866 * association remains valid on return.
869 pmap_page_lookup(vm_object_t object
, vm_pindex_t pindex
)
874 m
= vm_page_lookup(object
, pindex
);
875 } while (m
&& vm_page_sleep_busy(m
, 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 while (vm_page_sleep_busy(m
, FALSE
, "pmuwpt"))
930 KASSERT(m
->queue
== PQ_NONE
,
931 ("_pmap_unwire_pte_hold: %p->queue != PQ_NONE", m
));
933 if (m
->hold_count
== 1) {
935 * Unmap the page table page.
939 /* pmap_inval_add(info, pmap, -1); */
941 if (m
->pindex
>= (NUPDE
+ NUPDPE
)) {
944 pml4
= pmap_pml4e(pmap
, va
);
946 } else if (m
->pindex
>= NUPDE
) {
949 pdp
= pmap_pdpe(pmap
, va
);
954 pd
= pmap_pde(pmap
, va
);
958 KKASSERT(pmap
->pm_stats
.resident_count
> 0);
959 --pmap
->pm_stats
.resident_count
;
961 if (pmap
->pm_ptphint
== m
)
962 pmap
->pm_ptphint
= NULL
;
964 if (m
->pindex
< NUPDE
) {
965 /* We just released a PT, unhold the matching PD */
968 pdpg
= PHYS_TO_VM_PAGE(*pmap_pdpe(pmap
, va
) & VPTE_FRAME
);
969 pmap_unwire_pte_hold(pmap
, va
, pdpg
);
971 if (m
->pindex
>= NUPDE
&& m
->pindex
< (NUPDE
+ NUPDPE
)) {
972 /* We just released a PD, unhold the matching PDP */
975 pdppg
= PHYS_TO_VM_PAGE(*pmap_pml4e(pmap
, va
) & VPTE_FRAME
);
976 pmap_unwire_pte_hold(pmap
, va
, pdppg
);
980 * This was our last hold, the page had better be unwired
981 * after we decrement wire_count.
983 * FUTURE NOTE: shared page directory page could result in
984 * multiple wire counts.
988 KKASSERT(m
->wire_count
== 0);
989 --vmstats
.v_wire_count
;
990 vm_page_flag_clear(m
, PG_MAPPED
| PG_WRITEABLE
);
992 vm_page_free_zero(m
);
995 KKASSERT(m
->hold_count
> 1);
1002 pmap_unwire_pte_hold(pmap_t pmap
, vm_offset_t va
, vm_page_t m
)
1004 KKASSERT(m
->hold_count
> 0);
1005 if (m
->hold_count
> 1) {
1009 return _pmap_unwire_pte_hold(pmap
, va
, m
);
1014 * After removing a page table entry, this routine is used to
1015 * conditionally free the page, and manage the hold/wire counts.
1018 pmap_unuse_pt(pmap_t pmap
, vm_offset_t va
, vm_page_t mpte
)
1020 /* JG Use FreeBSD/amd64 or FreeBSD/i386 ptepde approaches? */
1021 vm_pindex_t ptepindex
;
1025 * page table pages in the kernel_pmap are not managed.
1027 if (pmap
== &kernel_pmap
)
1029 ptepindex
= pmap_pde_pindex(va
);
1030 if (pmap
->pm_ptphint
&&
1031 (pmap
->pm_ptphint
->pindex
== ptepindex
)) {
1032 mpte
= pmap
->pm_ptphint
;
1034 mpte
= pmap_page_lookup(pmap
->pm_pteobj
, ptepindex
);
1035 pmap
->pm_ptphint
= mpte
;
1039 return pmap_unwire_pte_hold(pmap
, va
, mpte
);
1043 * Initialize pmap0/vmspace0 . Since process 0 never enters user mode we
1044 * just dummy it up so it works well enough for fork().
1046 * In DragonFly, process pmaps may only be used to manipulate user address
1047 * space, never kernel address space.
1050 pmap_pinit0(struct pmap
*pmap
)
1056 * Initialize a preallocated and zeroed pmap structure,
1057 * such as one in a vmspace structure.
1060 pmap_pinit(struct pmap
*pmap
)
1065 * No need to allocate page table space yet but we do need a valid
1066 * page directory table.
1068 if (pmap
->pm_pml4
== NULL
) {
1070 (pml4_entry_t
*)kmem_alloc_pageable(&kernel_map
, PAGE_SIZE
);
1074 * Allocate an object for the ptes
1076 if (pmap
->pm_pteobj
== NULL
)
1077 pmap
->pm_pteobj
= vm_object_allocate(OBJT_DEFAULT
, NUPDE
+ NUPDPE
+ PML4PML4I
+ 1);
1080 * Allocate the page directory page, unless we already have
1081 * one cached. If we used the cached page the wire_count will
1082 * already be set appropriately.
1084 if ((ptdpg
= pmap
->pm_pdirm
) == NULL
) {
1085 ptdpg
= vm_page_grab(pmap
->pm_pteobj
, NUPDE
+ NUPDPE
+ PML4PML4I
,
1086 VM_ALLOC_NORMAL
| VM_ALLOC_RETRY
);
1087 pmap
->pm_pdirm
= ptdpg
;
1088 vm_page_flag_clear(ptdpg
, PG_MAPPED
| PG_BUSY
);
1089 ptdpg
->valid
= VM_PAGE_BITS_ALL
;
1090 if (ptdpg
->wire_count
== 0)
1091 ++vmstats
.v_wire_count
;
1092 ptdpg
->wire_count
= 1;
1093 pmap_kenter((vm_offset_t
)pmap
->pm_pml4
, VM_PAGE_TO_PHYS(ptdpg
));
1095 if ((ptdpg
->flags
& PG_ZERO
) == 0)
1096 bzero(pmap
->pm_pml4
, PAGE_SIZE
);
1099 pmap
->pm_active
= 0;
1100 pmap
->pm_ptphint
= NULL
;
1101 TAILQ_INIT(&pmap
->pm_pvlist
);
1102 bzero(&pmap
->pm_stats
, sizeof pmap
->pm_stats
);
1103 pmap
->pm_stats
.resident_count
= 1;
1107 * Clean up a pmap structure so it can be physically freed. This routine
1108 * is called by the vmspace dtor function. A great deal of pmap data is
1109 * left passively mapped to improve vmspace management so we have a bit
1110 * of cleanup work to do here.
1115 pmap_puninit(pmap_t pmap
)
1119 KKASSERT(pmap
->pm_active
== 0);
1120 lwkt_gettoken(&vm_token
);
1121 if ((p
= pmap
->pm_pdirm
) != NULL
) {
1122 KKASSERT(pmap
->pm_pml4
!= NULL
);
1123 pmap_kremove((vm_offset_t
)pmap
->pm_pml4
);
1125 vmstats
.v_wire_count
--;
1126 KKASSERT((p
->flags
& PG_BUSY
) == 0);
1128 vm_page_free_zero(p
);
1129 pmap
->pm_pdirm
= NULL
;
1131 lwkt_reltoken(&vm_token
);
1132 if (pmap
->pm_pml4
) {
1133 kmem_free(&kernel_map
, (vm_offset_t
)pmap
->pm_pml4
, PAGE_SIZE
);
1134 pmap
->pm_pml4
= NULL
;
1136 if (pmap
->pm_pteobj
) {
1137 vm_object_deallocate(pmap
->pm_pteobj
);
1138 pmap
->pm_pteobj
= NULL
;
1143 * Wire in kernel global address entries. To avoid a race condition
1144 * between pmap initialization and pmap_growkernel, this procedure
1145 * adds the pmap to the master list (which growkernel scans to update),
1146 * then copies the template.
1148 * In a virtual kernel there are no kernel global address entries.
1153 pmap_pinit2(struct pmap
*pmap
)
1156 lwkt_gettoken(&vm_token
);
1157 TAILQ_INSERT_TAIL(&pmap_list
, pmap
, pm_pmnode
);
1158 lwkt_reltoken(&vm_token
);
1163 * Attempt to release and free a vm_page in a pmap. Returns 1 on success,
1164 * 0 on failure (if the procedure had to sleep).
1166 * When asked to remove the page directory page itself, we actually just
1167 * leave it cached so we do not have to incur the SMP inval overhead of
1168 * removing the kernel mapping. pmap_puninit() will take care of it.
1171 pmap_release_free_page(struct pmap
*pmap
, vm_page_t p
)
1174 * This code optimizes the case of freeing non-busy
1175 * page-table pages. Those pages are zero now, and
1176 * might as well be placed directly into the zero queue.
1178 if (vm_page_sleep_busy(p
, FALSE
, "pmaprl"))
1184 * Remove the page table page from the processes address space.
1186 if (p
->pindex
== NUPDE
+ NUPDPE
+ PML4PML4I
) {
1188 * We are the pml4 table itself.
1190 /* XXX anything to do here? */
1191 } else if (p
->pindex
>= (NUPDE
+ NUPDPE
)) {
1193 * We are a PDP page.
1194 * We look for the PML4 entry that points to us.
1196 vm_page_t m4
= vm_page_lookup(pmap
->pm_pteobj
, NUPDE
+ NUPDPE
+ PML4PML4I
);
1197 KKASSERT(m4
!= NULL
);
1198 pml4_entry_t
*pml4
= (pml4_entry_t
*)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m4
));
1199 int idx
= (p
->pindex
- (NUPDE
+ NUPDPE
)) % NPML4EPG
;
1200 KKASSERT(pml4
[idx
] != 0);
1203 /* JG What about wire_count? */
1204 } else if (p
->pindex
>= NUPDE
) {
1207 * We look for the PDP entry that points to us.
1209 vm_page_t m3
= vm_page_lookup(pmap
->pm_pteobj
, NUPDE
+ NUPDPE
+ (p
->pindex
- NUPDE
) / NPDPEPG
);
1210 KKASSERT(m3
!= NULL
);
1211 pdp_entry_t
*pdp
= (pdp_entry_t
*)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m3
));
1212 int idx
= (p
->pindex
- NUPDE
) % NPDPEPG
;
1213 KKASSERT(pdp
[idx
] != 0);
1216 /* JG What about wire_count? */
1218 /* We are a PT page.
1219 * We look for the PD entry that points to us.
1221 vm_page_t m2
= vm_page_lookup(pmap
->pm_pteobj
, NUPDE
+ p
->pindex
/ NPDEPG
);
1222 KKASSERT(m2
!= NULL
);
1223 pd_entry_t
*pd
= (pd_entry_t
*)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m2
));
1224 int idx
= p
->pindex
% NPDEPG
;
1227 /* JG What about wire_count? */
1229 KKASSERT(pmap
->pm_stats
.resident_count
> 0);
1230 --pmap
->pm_stats
.resident_count
;
1232 if (p
->hold_count
) {
1233 panic("pmap_release: freeing held page table page");
1235 if (pmap
->pm_ptphint
&& (pmap
->pm_ptphint
->pindex
== p
->pindex
))
1236 pmap
->pm_ptphint
= NULL
;
1239 * We leave the top-level page table page cached, wired, and mapped in
1240 * the pmap until the dtor function (pmap_puninit()) gets called.
1241 * However, still clean it up so we can set PG_ZERO.
1243 if (p
->pindex
== NUPDE
+ NUPDPE
+ PML4PML4I
) {
1244 bzero(pmap
->pm_pml4
, PAGE_SIZE
);
1245 vm_page_flag_set(p
, PG_ZERO
);
1250 vmstats
.v_wire_count
--;
1251 /* JG eventually revert to using vm_page_free_zero() */
1258 * this routine is called if the page table page is not
1262 _pmap_allocpte(pmap_t pmap
, vm_pindex_t ptepindex
)
1264 vm_page_t m
, pdppg
, pdpg
;
1267 * Find or fabricate a new pagetable page
1269 m
= vm_page_grab(pmap
->pm_pteobj
, ptepindex
,
1270 VM_ALLOC_NORMAL
| VM_ALLOC_ZERO
| VM_ALLOC_RETRY
);
1272 if ((m
->flags
& PG_ZERO
) == 0) {
1273 pmap_zero_page(VM_PAGE_TO_PHYS(m
));
1276 KASSERT(m
->queue
== PQ_NONE
,
1277 ("_pmap_allocpte: %p->queue != PQ_NONE", m
));
1280 * Increment the hold count for the page we will be returning to
1285 if (m
->wire_count
== 0)
1286 vmstats
.v_wire_count
++;
1290 * Map the pagetable page into the process address space, if
1291 * it isn't already there.
1294 ++pmap
->pm_stats
.resident_count
;
1296 if (ptepindex
>= (NUPDE
+ NUPDPE
)) {
1298 vm_pindex_t pml4index
;
1300 /* Wire up a new PDP page */
1301 pml4index
= ptepindex
- (NUPDE
+ NUPDPE
);
1302 pml4
= &pmap
->pm_pml4
[pml4index
];
1303 *pml4
= VM_PAGE_TO_PHYS(m
) | VPTE_R
| VPTE_W
| VPTE_V
|
1305 } else if (ptepindex
>= NUPDE
) {
1306 vm_pindex_t pml4index
;
1307 vm_pindex_t pdpindex
;
1311 /* Wire up a new PD page */
1312 pdpindex
= ptepindex
- NUPDE
;
1313 pml4index
= pdpindex
>> NPML4EPGSHIFT
;
1315 pml4
= &pmap
->pm_pml4
[pml4index
];
1316 if ((*pml4
& VPTE_V
) == 0) {
1317 /* Have to allocate a new PDP page, recurse */
1318 if (_pmap_allocpte(pmap
, NUPDE
+ NUPDPE
+ pml4index
)
1325 /* Add reference to the PDP page */
1326 pdppg
= PHYS_TO_VM_PAGE(*pml4
& VPTE_FRAME
);
1327 pdppg
->hold_count
++;
1329 pdp
= (pdp_entry_t
*)PHYS_TO_DMAP(*pml4
& VPTE_FRAME
);
1331 /* Now find the pdp page */
1332 pdp
= &pdp
[pdpindex
& ((1ul << NPDPEPGSHIFT
) - 1)];
1333 KKASSERT(*pdp
== 0); /* JG DEBUG64 */
1334 *pdp
= VM_PAGE_TO_PHYS(m
) | VPTE_R
| VPTE_W
| VPTE_V
|
1337 vm_pindex_t pml4index
;
1338 vm_pindex_t pdpindex
;
1343 /* Wire up a new PT page */
1344 pdpindex
= ptepindex
>> NPDPEPGSHIFT
;
1345 pml4index
= pdpindex
>> NPML4EPGSHIFT
;
1347 /* First, find the pdp and check that its valid. */
1348 pml4
= &pmap
->pm_pml4
[pml4index
];
1349 if ((*pml4
& VPTE_V
) == 0) {
1350 /* We miss a PDP page. We ultimately need a PD page.
1351 * Recursively allocating a PD page will allocate
1352 * the missing PDP page and will also allocate
1353 * the PD page we need.
1355 /* Have to allocate a new PD page, recurse */
1356 if (_pmap_allocpte(pmap
, NUPDE
+ pdpindex
)
1362 pdp
= (pdp_entry_t
*)PHYS_TO_DMAP(*pml4
& VPTE_FRAME
);
1363 pdp
= &pdp
[pdpindex
& ((1ul << NPDPEPGSHIFT
) - 1)];
1365 pdp
= (pdp_entry_t
*)PHYS_TO_DMAP(*pml4
& VPTE_FRAME
);
1366 pdp
= &pdp
[pdpindex
& ((1ul << NPDPEPGSHIFT
) - 1)];
1367 if ((*pdp
& VPTE_V
) == 0) {
1368 /* Have to allocate a new PD page, recurse */
1369 if (_pmap_allocpte(pmap
, NUPDE
+ pdpindex
)
1376 /* Add reference to the PD page */
1377 pdpg
= PHYS_TO_VM_PAGE(*pdp
& VPTE_FRAME
);
1381 pd
= (pd_entry_t
*)PHYS_TO_DMAP(*pdp
& VPTE_FRAME
);
1383 /* Now we know where the page directory page is */
1384 pd
= &pd
[ptepindex
& ((1ul << NPDEPGSHIFT
) - 1)];
1385 KKASSERT(*pd
== 0); /* JG DEBUG64 */
1386 *pd
= VM_PAGE_TO_PHYS(m
) | VPTE_R
| VPTE_W
| VPTE_V
|
1391 * Set the page table hint
1393 pmap
->pm_ptphint
= m
;
1395 m
->valid
= VM_PAGE_BITS_ALL
;
1396 vm_page_flag_clear(m
, PG_ZERO
);
1397 vm_page_flag_set(m
, PG_MAPPED
);
1404 * Determine the page table page required to access the VA in the pmap
1405 * and allocate it if necessary. Return a held vm_page_t for the page.
1407 * Only used with user pmaps.
1410 pmap_allocpte(pmap_t pmap
, vm_offset_t va
)
1412 vm_pindex_t ptepindex
;
1417 * Calculate pagetable page index
1419 ptepindex
= pmap_pde_pindex(va
);
1422 * Get the page directory entry
1424 pd
= pmap_pde(pmap
, va
);
1427 * This supports switching from a 2MB page to a
1430 if (pd
!= NULL
&& (*pd
& (VPTE_PS
| VPTE_V
)) == (VPTE_PS
| VPTE_V
)) {
1431 panic("no promotion/demotion yet");
1439 * If the page table page is mapped, we just increment the
1440 * hold count, and activate it.
1442 if (pd
!= NULL
&& (*pd
& VPTE_V
) != 0) {
1443 /* YYY hint is used here on i386 */
1444 m
= pmap_page_lookup( pmap
->pm_pteobj
, ptepindex
);
1445 pmap
->pm_ptphint
= m
;
1450 * Here if the pte page isn't mapped, or if it has been deallocated.
1452 return _pmap_allocpte(pmap
, ptepindex
);
1456 /***************************************************
1457 * Pmap allocation/deallocation routines.
1458 ***************************************************/
1461 * Release any resources held by the given physical map.
1462 * Called when a pmap initialized by pmap_pinit is being released.
1463 * Should only be called if the map contains no valid mappings.
1467 static int pmap_release_callback(struct vm_page
*p
, void *data
);
1470 pmap_release(struct pmap
*pmap
)
1472 vm_object_t object
= pmap
->pm_pteobj
;
1473 struct rb_vm_page_scan_info info
;
1475 KKASSERT(pmap
!= &kernel_pmap
);
1477 #if defined(DIAGNOSTIC)
1478 if (object
->ref_count
!= 1)
1479 panic("pmap_release: pteobj reference count != 1");
1483 info
.object
= object
;
1485 lwkt_gettoken(&vm_token
);
1486 TAILQ_REMOVE(&pmap_list
, pmap
, pm_pmnode
);
1493 info
.limit
= object
->generation
;
1495 vm_page_rb_tree_RB_SCAN(&object
->rb_memq
, NULL
,
1496 pmap_release_callback
, &info
);
1497 if (info
.error
== 0 && info
.mpte
) {
1498 if (!pmap_release_free_page(pmap
, info
.mpte
))
1502 } while (info
.error
);
1503 lwkt_reltoken(&vm_token
);
1507 pmap_release_callback(struct vm_page
*p
, void *data
)
1509 struct rb_vm_page_scan_info
*info
= data
;
1511 if (p
->pindex
== NUPDE
+ NUPDPE
+ PML4PML4I
) {
1515 if (!pmap_release_free_page(info
->pmap
, p
)) {
1519 if (info
->object
->generation
!= info
->limit
) {
1527 * Grow the number of kernel page table entries, if needed.
1532 pmap_growkernel(vm_offset_t kstart
, vm_offset_t kend
)
1536 vm_offset_t ptppaddr
;
1538 pd_entry_t
*pde
, newpdir
;
1544 lwkt_gettoken(&vm_token
);
1545 if (kernel_vm_end
== 0) {
1546 kernel_vm_end
= KvaStart
;
1548 while ((*pmap_pde(&kernel_pmap
, kernel_vm_end
) & VPTE_V
) != 0) {
1549 kernel_vm_end
= (kernel_vm_end
+ PAGE_SIZE
* NPTEPG
) & ~(PAGE_SIZE
* NPTEPG
- 1);
1551 if (kernel_vm_end
- 1 >= kernel_map
.max_offset
) {
1552 kernel_vm_end
= kernel_map
.max_offset
;
1557 addr
= roundup2(addr
, PAGE_SIZE
* NPTEPG
);
1558 if (addr
- 1 >= kernel_map
.max_offset
)
1559 addr
= kernel_map
.max_offset
;
1560 while (kernel_vm_end
< addr
) {
1561 pde
= pmap_pde(&kernel_pmap
, kernel_vm_end
);
1563 /* We need a new PDP entry */
1564 nkpg
= vm_page_alloc(kptobj
, nkpt
,
1565 VM_ALLOC_NORMAL
| VM_ALLOC_SYSTEM
1566 | VM_ALLOC_INTERRUPT
);
1568 panic("pmap_growkernel: no memory to "
1571 paddr
= VM_PAGE_TO_PHYS(nkpg
);
1572 if ((nkpg
->flags
& PG_ZERO
) == 0)
1573 pmap_zero_page(paddr
);
1574 vm_page_flag_clear(nkpg
, PG_ZERO
);
1575 newpdp
= (pdp_entry_t
)(paddr
| VPTE_V
| VPTE_R
|
1576 VPTE_W
| VPTE_A
| VPTE_M
);
1577 *pmap_pdpe(&kernel_pmap
, kernel_vm_end
) = newpdp
;
1579 continue; /* try again */
1581 if ((*pde
& VPTE_V
) != 0) {
1582 kernel_vm_end
= (kernel_vm_end
+ PAGE_SIZE
* NPTEPG
) &
1583 ~(PAGE_SIZE
* NPTEPG
- 1);
1584 if (kernel_vm_end
- 1 >= kernel_map
.max_offset
) {
1585 kernel_vm_end
= kernel_map
.max_offset
;
1592 * This index is bogus, but out of the way
1594 nkpg
= vm_page_alloc(kptobj
, nkpt
,
1597 VM_ALLOC_INTERRUPT
);
1599 panic("pmap_growkernel: no memory to grow kernel");
1602 ptppaddr
= VM_PAGE_TO_PHYS(nkpg
);
1603 pmap_zero_page(ptppaddr
);
1604 vm_page_flag_clear(nkpg
, PG_ZERO
);
1605 newpdir
= (pd_entry_t
)(ptppaddr
| VPTE_V
| VPTE_R
|
1606 VPTE_W
| VPTE_A
| VPTE_M
);
1607 *pmap_pde(&kernel_pmap
, kernel_vm_end
) = newpdir
;
1610 kernel_vm_end
= (kernel_vm_end
+ PAGE_SIZE
* NPTEPG
) &
1611 ~(PAGE_SIZE
* NPTEPG
- 1);
1612 if (kernel_vm_end
- 1 >= kernel_map
.max_offset
) {
1613 kernel_vm_end
= kernel_map
.max_offset
;
1617 lwkt_reltoken(&vm_token
);
1622 * Retire the given physical map from service. Should only be called
1623 * if the map contains no valid mappings.
1628 pmap_destroy(pmap_t pmap
)
1633 lwkt_gettoken(&vm_token
);
1634 if (--pmap
->pm_count
== 0) {
1636 panic("destroying a pmap is not yet implemented");
1638 lwkt_reltoken(&vm_token
);
1642 * Add a reference to the specified pmap.
1647 pmap_reference(pmap_t pmap
)
1650 lwkt_gettoken(&vm_token
);
1652 lwkt_reltoken(&vm_token
);
1656 /************************************************************************
1657 * VMSPACE MANAGEMENT *
1658 ************************************************************************
1660 * The VMSPACE management we do in our virtual kernel must be reflected
1661 * in the real kernel. This is accomplished by making vmspace system
1662 * calls to the real kernel.
1665 cpu_vmspace_alloc(struct vmspace
*vm
)
1671 #define USER_SIZE (VM_MAX_USER_ADDRESS - VM_MIN_USER_ADDRESS)
1673 if (vmspace_create(&vm
->vm_pmap
, 0, NULL
) < 0)
1674 panic("vmspace_create() failed");
1676 rp
= vmspace_mmap(&vm
->vm_pmap
, VM_MIN_USER_ADDRESS
, USER_SIZE
,
1677 PROT_READ
|PROT_WRITE
,
1678 MAP_FILE
|MAP_SHARED
|MAP_VPAGETABLE
|MAP_FIXED
,
1680 if (rp
== MAP_FAILED
)
1681 panic("vmspace_mmap: failed");
1682 vmspace_mcontrol(&vm
->vm_pmap
, VM_MIN_USER_ADDRESS
, USER_SIZE
,
1684 vpte
= VM_PAGE_TO_PHYS(vmspace_pmap(vm
)->pm_pdirm
) | VPTE_R
| VPTE_W
| VPTE_V
;
1685 r
= vmspace_mcontrol(&vm
->vm_pmap
, VM_MIN_USER_ADDRESS
, USER_SIZE
,
1688 panic("vmspace_mcontrol: failed");
1692 cpu_vmspace_free(struct vmspace
*vm
)
1694 if (vmspace_destroy(&vm
->vm_pmap
) < 0)
1695 panic("vmspace_destroy() failed");
1698 /***************************************************
1699 * page management routines.
1700 ***************************************************/
1703 * free the pv_entry back to the free list. This function may be
1704 * called from an interrupt.
1706 static __inline
void
1707 free_pv_entry(pv_entry_t pv
)
1710 KKASSERT(pv_entry_count
>= 0);
1715 * get a new pv_entry, allocating a block from the system
1716 * when needed. This function may be called from an interrupt.
1722 if (pv_entry_high_water
&&
1723 (pv_entry_count
> pv_entry_high_water
) &&
1724 (pmap_pagedaemon_waken
== 0)) {
1725 pmap_pagedaemon_waken
= 1;
1726 wakeup(&vm_pages_needed
);
1728 return zalloc(pvzone
);
1732 * This routine is very drastic, but can save the system
1742 static int warningdone
=0;
1744 if (pmap_pagedaemon_waken
== 0)
1746 lwkt_gettoken(&vm_token
);
1747 pmap_pagedaemon_waken
= 0;
1749 if (warningdone
< 5) {
1750 kprintf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n");
1754 for(i
= 0; i
< vm_page_array_size
; i
++) {
1755 m
= &vm_page_array
[i
];
1756 if (m
->wire_count
|| m
->hold_count
|| m
->busy
||
1757 (m
->flags
& PG_BUSY
))
1761 lwkt_reltoken(&vm_token
);
1766 * If it is the first entry on the list, it is actually
1767 * in the header and we must copy the following entry up
1768 * to the header. Otherwise we must search the list for
1769 * the entry. In either case we free the now unused entry.
1772 pmap_remove_entry(struct pmap
*pmap
, vm_page_t m
, vm_offset_t va
)
1778 if (m
->md
.pv_list_count
< pmap
->pm_stats
.resident_count
) {
1779 TAILQ_FOREACH(pv
, &m
->md
.pv_list
, pv_list
) {
1780 if (pmap
== pv
->pv_pmap
&& va
== pv
->pv_va
)
1784 TAILQ_FOREACH(pv
, &pmap
->pm_pvlist
, pv_plist
) {
1785 if (va
== pv
->pv_va
)
1791 * Note that pv_ptem is NULL if the page table page itself is not
1792 * managed, even if the page being removed IS managed.
1795 /* JGXXX When can 'pv' be NULL? */
1797 TAILQ_REMOVE(&m
->md
.pv_list
, pv
, pv_list
);
1798 m
->md
.pv_list_count
--;
1799 m
->object
->agg_pv_list_count
--;
1800 KKASSERT(m
->md
.pv_list_count
>= 0);
1801 if (TAILQ_EMPTY(&m
->md
.pv_list
))
1802 vm_page_flag_clear(m
, PG_MAPPED
| PG_WRITEABLE
);
1803 TAILQ_REMOVE(&pmap
->pm_pvlist
, pv
, pv_plist
);
1804 ++pmap
->pm_generation
;
1805 rtval
= pmap_unuse_pt(pmap
, va
, pv
->pv_ptem
);
1813 * Create a pv entry for page at pa for (pmap, va). If the page table page
1814 * holding the VA is managed, mpte will be non-NULL.
1817 pmap_insert_entry(pmap_t pmap
, vm_offset_t va
, vm_page_t mpte
, vm_page_t m
)
1822 pv
= get_pv_entry();
1827 TAILQ_INSERT_TAIL(&pmap
->pm_pvlist
, pv
, pv_plist
);
1828 TAILQ_INSERT_TAIL(&m
->md
.pv_list
, pv
, pv_list
);
1829 m
->md
.pv_list_count
++;
1830 m
->object
->agg_pv_list_count
++;
1836 * pmap_remove_pte: do the things to unmap a page in a process
1839 pmap_remove_pte(struct pmap
*pmap
, pt_entry_t
*ptq
, vm_offset_t va
)
1844 oldpte
= pmap_inval_loadandclear(ptq
, pmap
, va
);
1845 if (oldpte
& VPTE_WIRED
)
1846 --pmap
->pm_stats
.wired_count
;
1847 KKASSERT(pmap
->pm_stats
.wired_count
>= 0);
1851 * Machines that don't support invlpg, also don't support
1852 * PG_G. XXX PG_G is disabled for SMP so don't worry about
1856 cpu_invlpg((void *)va
);
1858 KKASSERT(pmap
->pm_stats
.resident_count
> 0);
1859 --pmap
->pm_stats
.resident_count
;
1860 if (oldpte
& VPTE_MANAGED
) {
1861 m
= PHYS_TO_VM_PAGE(oldpte
);
1862 if (oldpte
& VPTE_M
) {
1863 #if defined(PMAP_DIAGNOSTIC)
1864 if (pmap_nw_modified((pt_entry_t
) oldpte
)) {
1866 "pmap_remove: modified page not writable: va: 0x%lx, pte: 0x%lx\n",
1870 if (pmap_track_modified(pmap
, va
))
1873 if (oldpte
& VPTE_A
)
1874 vm_page_flag_set(m
, PG_REFERENCED
);
1875 return pmap_remove_entry(pmap
, m
, va
);
1877 return pmap_unuse_pt(pmap
, va
, NULL
);
1886 * Remove a single page from a process address space.
1888 * This function may not be called from an interrupt if the pmap is
1892 pmap_remove_page(struct pmap
*pmap
, vm_offset_t va
)
1896 pte
= pmap_pte(pmap
, va
);
1899 if ((*pte
& VPTE_V
) == 0)
1901 pmap_remove_pte(pmap
, pte
, va
);
1905 * Remove the given range of addresses from the specified map.
1907 * It is assumed that the start and end are properly rounded to
1910 * This function may not be called from an interrupt if the pmap is
1916 pmap_remove(struct pmap
*pmap
, vm_offset_t sva
, vm_offset_t eva
)
1918 vm_offset_t va_next
;
1919 pml4_entry_t
*pml4e
;
1921 pd_entry_t ptpaddr
, *pde
;
1927 lwkt_gettoken(&vm_token
);
1928 KKASSERT(pmap
->pm_stats
.resident_count
>= 0);
1929 if (pmap
->pm_stats
.resident_count
== 0) {
1930 lwkt_reltoken(&vm_token
);
1935 * special handling of removing one page. a very
1936 * common operation and easy to short circuit some
1939 if (sva
+ PAGE_SIZE
== eva
) {
1940 pde
= pmap_pde(pmap
, sva
);
1941 if (pde
&& (*pde
& VPTE_PS
) == 0) {
1942 pmap_remove_page(pmap
, sva
);
1943 lwkt_reltoken(&vm_token
);
1948 for (; sva
< eva
; sva
= va_next
) {
1949 pml4e
= pmap_pml4e(pmap
, sva
);
1950 if ((*pml4e
& VPTE_V
) == 0) {
1951 va_next
= (sva
+ NBPML4
) & ~PML4MASK
;
1957 pdpe
= pmap_pml4e_to_pdpe(pml4e
, sva
);
1958 if ((*pdpe
& VPTE_V
) == 0) {
1959 va_next
= (sva
+ NBPDP
) & ~PDPMASK
;
1966 * Calculate index for next page table.
1968 va_next
= (sva
+ NBPDR
) & ~PDRMASK
;
1972 pde
= pmap_pdpe_to_pde(pdpe
, sva
);
1976 * Weed out invalid mappings.
1982 * Check for large page.
1984 if ((ptpaddr
& VPTE_PS
) != 0) {
1985 /* JG FreeBSD has more complex treatment here */
1986 KKASSERT(*pde
!= 0);
1987 pmap_inval_pde(pde
, pmap
, sva
);
1988 pmap
->pm_stats
.resident_count
-= NBPDR
/ PAGE_SIZE
;
1993 * Limit our scan to either the end of the va represented
1994 * by the current page table page, or to the end of the
1995 * range being removed.
2001 * NOTE: pmap_remove_pte() can block.
2003 for (pte
= pmap_pde_to_pte(pde
, sva
); sva
!= va_next
; pte
++,
2007 if (pmap_remove_pte(pmap
, pte
, sva
))
2011 lwkt_reltoken(&vm_token
);
2015 * Removes this physical page from all physical maps in which it resides.
2016 * Reflects back modify bits to the pager.
2018 * This routine may not be called from an interrupt.
2024 pmap_remove_all(vm_page_t m
)
2026 pt_entry_t
*pte
, tpte
;
2029 #if defined(PMAP_DIAGNOSTIC)
2031 * XXX this makes pmap_page_protect(NONE) illegal for non-managed
2034 if (!pmap_initialized
|| (m
->flags
& PG_FICTITIOUS
)) {
2035 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%08llx", (long long)VM_PAGE_TO_PHYS(m
));
2040 lwkt_gettoken(&vm_token
);
2041 while ((pv
= TAILQ_FIRST(&m
->md
.pv_list
)) != NULL
) {
2042 KKASSERT(pv
->pv_pmap
->pm_stats
.resident_count
> 0);
2043 --pv
->pv_pmap
->pm_stats
.resident_count
;
2045 pte
= pmap_pte(pv
->pv_pmap
, pv
->pv_va
);
2046 KKASSERT(pte
!= NULL
);
2048 tpte
= pmap_inval_loadandclear(pte
, pv
->pv_pmap
, pv
->pv_va
);
2049 if (tpte
& VPTE_WIRED
)
2050 pv
->pv_pmap
->pm_stats
.wired_count
--;
2051 KKASSERT(pv
->pv_pmap
->pm_stats
.wired_count
>= 0);
2054 vm_page_flag_set(m
, PG_REFERENCED
);
2057 * Update the vm_page_t clean and reference bits.
2059 if (tpte
& VPTE_M
) {
2060 #if defined(PMAP_DIAGNOSTIC)
2061 if (pmap_nw_modified(tpte
)) {
2063 "pmap_remove_all: modified page not writable: va: 0x%lx, pte: 0x%lx\n",
2067 if (pmap_track_modified(pv
->pv_pmap
, pv
->pv_va
))
2070 TAILQ_REMOVE(&m
->md
.pv_list
, pv
, pv_list
);
2071 TAILQ_REMOVE(&pv
->pv_pmap
->pm_pvlist
, pv
, pv_plist
);
2072 ++pv
->pv_pmap
->pm_generation
;
2073 m
->md
.pv_list_count
--;
2074 m
->object
->agg_pv_list_count
--;
2075 KKASSERT(m
->md
.pv_list_count
>= 0);
2076 if (TAILQ_EMPTY(&m
->md
.pv_list
))
2077 vm_page_flag_clear(m
, PG_MAPPED
| PG_WRITEABLE
);
2078 pmap_unuse_pt(pv
->pv_pmap
, pv
->pv_va
, pv
->pv_ptem
);
2081 KKASSERT((m
->flags
& (PG_MAPPED
|PG_WRITEABLE
)) == 0);
2082 lwkt_reltoken(&vm_token
);
2087 * Set the physical protection on the specified range of this map
2090 * This function may not be called from an interrupt if the map is
2091 * not the kernel_pmap.
2096 pmap_protect(pmap_t pmap
, vm_offset_t sva
, vm_offset_t eva
, vm_prot_t prot
)
2098 vm_offset_t va_next
;
2099 pml4_entry_t
*pml4e
;
2101 pd_entry_t ptpaddr
, *pde
;
2104 /* JG review for NX */
2109 if ((prot
& VM_PROT_READ
) == VM_PROT_NONE
) {
2110 pmap_remove(pmap
, sva
, eva
);
2114 if (prot
& VM_PROT_WRITE
)
2117 lwkt_gettoken(&vm_token
);
2119 for (; sva
< eva
; sva
= va_next
) {
2121 pml4e
= pmap_pml4e(pmap
, sva
);
2122 if ((*pml4e
& VPTE_V
) == 0) {
2123 va_next
= (sva
+ NBPML4
) & ~PML4MASK
;
2129 pdpe
= pmap_pml4e_to_pdpe(pml4e
, sva
);
2130 if ((*pdpe
& VPTE_V
) == 0) {
2131 va_next
= (sva
+ NBPDP
) & ~PDPMASK
;
2137 va_next
= (sva
+ NBPDR
) & ~PDRMASK
;
2141 pde
= pmap_pdpe_to_pde(pdpe
, sva
);
2145 * Check for large page.
2147 if ((ptpaddr
& VPTE_PS
) != 0) {
2149 pmap_clean_pde(pde
, pmap
, sva
);
2150 pmap
->pm_stats
.resident_count
-= NBPDR
/ PAGE_SIZE
;
2155 * Weed out invalid mappings. Note: we assume that the page
2156 * directory table is always allocated, and in kernel virtual.
2164 for (pte
= pmap_pde_to_pte(pde
, sva
); sva
!= va_next
; pte
++,
2170 * Clean managed pages and also check the accessed
2171 * bit. Just remove write perms for unmanaged
2172 * pages. Be careful of races, turning off write
2173 * access will force a fault rather then setting
2174 * the modified bit at an unexpected time.
2176 if (*pte
& VPTE_MANAGED
) {
2177 pbits
= pmap_clean_pte(pte
, pmap
, sva
);
2179 if (pbits
& VPTE_A
) {
2180 m
= PHYS_TO_VM_PAGE(pbits
& VPTE_FRAME
);
2181 vm_page_flag_set(m
, PG_REFERENCED
);
2182 atomic_clear_long(pte
, VPTE_A
);
2184 if (pbits
& VPTE_M
) {
2185 if (pmap_track_modified(pmap
, sva
)) {
2187 m
= PHYS_TO_VM_PAGE(pbits
& VPTE_FRAME
);
2192 pbits
= pmap_setro_pte(pte
, pmap
, sva
);
2196 lwkt_reltoken(&vm_token
);
2200 * Enter a managed page into a pmap. If the page is not wired related pmap
2201 * data can be destroyed at any time for later demand-operation.
2203 * Insert the vm_page (m) at virtual address (v) in (pmap), with the
2204 * specified protection, and wire the mapping if requested.
2206 * NOTE: This routine may not lazy-evaluate or lose information. The
2207 * page must actually be inserted into the given map NOW.
2209 * NOTE: When entering a page at a KVA address, the pmap must be the
2215 pmap_enter(pmap_t pmap
, vm_offset_t va
, vm_page_t m
, vm_prot_t prot
,
2222 pt_entry_t origpte
, newpte
;
2228 va
= trunc_page(va
);
2230 lwkt_gettoken(&vm_token
);
2233 * Get the page table page. The kernel_pmap's page table pages
2234 * are preallocated and have no associated vm_page_t.
2236 if (pmap
== &kernel_pmap
)
2239 mpte
= pmap_allocpte(pmap
, va
);
2241 pde
= pmap_pde(pmap
, va
);
2242 if (pde
!= NULL
&& (*pde
& VPTE_V
) != 0) {
2243 if ((*pde
& VPTE_PS
) != 0)
2244 panic("pmap_enter: attempted pmap_enter on 2MB page");
2245 pte
= pmap_pde_to_pte(pde
, va
);
2247 panic("pmap_enter: invalid page directory va=%#lx", va
);
2250 KKASSERT(pte
!= NULL
);
2252 * Deal with races on the original mapping (though don't worry
2253 * about VPTE_A races) by cleaning it. This will force a fault
2254 * if an attempt is made to write to the page.
2256 pa
= VM_PAGE_TO_PHYS(m
);
2257 origpte
= pmap_clean_pte(pte
, pmap
, va
);
2258 opa
= origpte
& VPTE_FRAME
;
2260 if (origpte
& VPTE_PS
)
2261 panic("pmap_enter: attempted pmap_enter on 2MB page");
2264 * Mapping has not changed, must be protection or wiring change.
2266 if (origpte
&& (opa
== pa
)) {
2268 * Wiring change, just update stats. We don't worry about
2269 * wiring PT pages as they remain resident as long as there
2270 * are valid mappings in them. Hence, if a user page is wired,
2271 * the PT page will be also.
2273 if (wired
&& ((origpte
& VPTE_WIRED
) == 0))
2274 ++pmap
->pm_stats
.wired_count
;
2275 else if (!wired
&& (origpte
& VPTE_WIRED
))
2276 --pmap
->pm_stats
.wired_count
;
2279 * Remove the extra pte reference. Note that we cannot
2280 * optimize the RO->RW case because we have adjusted the
2281 * wiring count above and may need to adjust the wiring
2288 * We might be turning off write access to the page,
2289 * so we go ahead and sense modify status.
2291 if (origpte
& VPTE_MANAGED
) {
2292 if ((origpte
& VPTE_M
) &&
2293 pmap_track_modified(pmap
, va
)) {
2295 om
= PHYS_TO_VM_PAGE(opa
);
2299 KKASSERT(m
->flags
& PG_MAPPED
);
2304 * Mapping has changed, invalidate old range and fall through to
2305 * handle validating new mapping.
2309 err
= pmap_remove_pte(pmap
, pte
, va
);
2311 panic("pmap_enter: pte vanished, va: 0x%lx", va
);
2315 * Enter on the PV list if part of our managed memory. Note that we
2316 * raise IPL while manipulating pv_table since pmap_enter can be
2317 * called at interrupt time.
2319 if (pmap_initialized
&&
2320 (m
->flags
& (PG_FICTITIOUS
|PG_UNMANAGED
)) == 0) {
2321 pmap_insert_entry(pmap
, va
, mpte
, m
);
2323 vm_page_flag_set(m
, PG_MAPPED
);
2327 * Increment counters
2329 ++pmap
->pm_stats
.resident_count
;
2331 pmap
->pm_stats
.wired_count
++;
2335 * Now validate mapping with desired protection/wiring.
2337 newpte
= (pt_entry_t
) (pa
| pte_prot(pmap
, prot
) | VPTE_V
);
2340 newpte
|= VPTE_WIRED
;
2341 if (pmap
!= &kernel_pmap
)
2345 * If the mapping or permission bits are different from the
2346 * (now cleaned) original pte, an update is needed. We've
2347 * already downgraded or invalidated the page so all we have
2348 * to do now is update the bits.
2350 * XXX should we synchronize RO->RW changes to avoid another
2353 if ((origpte
& ~(VPTE_W
|VPTE_M
|VPTE_A
)) != newpte
) {
2354 *pte
= newpte
| VPTE_A
;
2355 if (newpte
& VPTE_W
)
2356 vm_page_flag_set(m
, PG_WRITEABLE
);
2358 KKASSERT((newpte
& VPTE_MANAGED
) == 0 || (m
->flags
& PG_MAPPED
));
2359 lwkt_reltoken(&vm_token
);
2363 * This code works like pmap_enter() but assumes VM_PROT_READ and not-wired.
2365 * Currently this routine may only be used on user pmaps, not kernel_pmap.
2370 pmap_enter_quick(pmap_t pmap
, vm_offset_t va
, vm_page_t m
)
2375 vm_pindex_t ptepindex
;
2378 KKASSERT(pmap
!= &kernel_pmap
);
2380 KKASSERT(va
>= VM_MIN_USER_ADDRESS
&& va
< VM_MAX_USER_ADDRESS
);
2383 * Calculate pagetable page index
2385 ptepindex
= pmap_pde_pindex(va
);
2387 lwkt_gettoken(&vm_token
);
2391 * Get the page directory entry
2393 ptepa
= pmap_pde(pmap
, va
);
2396 * If the page table page is mapped, we just increment
2397 * the hold count, and activate it.
2399 if (ptepa
&& (*ptepa
& VPTE_V
) != 0) {
2400 if (*ptepa
& VPTE_PS
)
2401 panic("pmap_enter_quick: unexpected mapping into 2MB page");
2402 if (pmap
->pm_ptphint
&&
2403 (pmap
->pm_ptphint
->pindex
== ptepindex
)) {
2404 mpte
= pmap
->pm_ptphint
;
2406 mpte
= pmap_page_lookup( pmap
->pm_pteobj
, ptepindex
);
2407 pmap
->pm_ptphint
= mpte
;
2412 mpte
= _pmap_allocpte(pmap
, ptepindex
);
2414 } while (mpte
== NULL
);
2417 * Ok, now that the page table page has been validated, get the pte.
2418 * If the pte is already mapped undo mpte's hold_count and
2421 pte
= pmap_pte(pmap
, va
);
2422 if (*pte
& VPTE_V
) {
2423 KKASSERT(mpte
!= NULL
);
2424 pmap_unwire_pte_hold(pmap
, va
, mpte
);
2425 pa
= VM_PAGE_TO_PHYS(m
);
2426 KKASSERT(((*pte
^ pa
) & VPTE_FRAME
) == 0);
2427 lwkt_reltoken(&vm_token
);
2432 * Enter on the PV list if part of our managed memory
2434 if ((m
->flags
& (PG_FICTITIOUS
|PG_UNMANAGED
)) == 0) {
2435 pmap_insert_entry(pmap
, va
, mpte
, m
);
2436 vm_page_flag_set(m
, PG_MAPPED
);
2440 * Increment counters
2442 ++pmap
->pm_stats
.resident_count
;
2444 pa
= VM_PAGE_TO_PHYS(m
);
2447 * Now validate mapping with RO protection
2449 if (m
->flags
& (PG_FICTITIOUS
|PG_UNMANAGED
))
2450 *pte
= (vpte_t
)pa
| VPTE_V
| VPTE_U
;
2452 *pte
= (vpte_t
)pa
| VPTE_V
| VPTE_U
| VPTE_MANAGED
;
2453 /*pmap_inval_add(&info, pmap, va); shouldn't be needed 0->valid */
2454 /*pmap_inval_flush(&info); don't need for vkernel */
2455 lwkt_reltoken(&vm_token
);
2459 * Make a temporary mapping for a physical address. This is only intended
2460 * to be used for panic dumps.
2463 pmap_kenter_temporary(vm_paddr_t pa
, int i
)
2465 pmap_kenter(crashdumpmap
+ (i
* PAGE_SIZE
), pa
);
2466 return ((void *)crashdumpmap
);
2469 #define MAX_INIT_PT (96)
2472 * This routine preloads the ptes for a given object into the specified pmap.
2473 * This eliminates the blast of soft faults on process startup and
2474 * immediately after an mmap.
2478 static int pmap_object_init_pt_callback(vm_page_t p
, void *data
);
2481 pmap_object_init_pt(pmap_t pmap
, vm_offset_t addr
, vm_prot_t prot
,
2482 vm_object_t object
, vm_pindex_t pindex
,
2483 vm_size_t size
, int limit
)
2485 struct rb_vm_page_scan_info info
;
2490 * We can't preinit if read access isn't set or there is no pmap
2493 if ((prot
& VM_PROT_READ
) == 0 || pmap
== NULL
|| object
== NULL
)
2497 * We can't preinit if the pmap is not the current pmap
2499 lp
= curthread
->td_lwp
;
2500 if (lp
== NULL
|| pmap
!= vmspace_pmap(lp
->lwp_vmspace
))
2503 psize
= x86_64_btop(size
);
2505 if ((object
->type
!= OBJT_VNODE
) ||
2506 ((limit
& MAP_PREFAULT_PARTIAL
) && (psize
> MAX_INIT_PT
) &&
2507 (object
->resident_page_count
> MAX_INIT_PT
))) {
2511 if (psize
+ pindex
> object
->size
) {
2512 if (object
->size
< pindex
)
2514 psize
= object
->size
- pindex
;
2521 * Use a red-black scan to traverse the requested range and load
2522 * any valid pages found into the pmap.
2524 * We cannot safely scan the object's memq unless we are in a
2525 * critical section since interrupts can remove pages from objects.
2527 info
.start_pindex
= pindex
;
2528 info
.end_pindex
= pindex
+ psize
- 1;
2535 lwkt_gettoken(&vm_token
);
2536 vm_page_rb_tree_RB_SCAN(&object
->rb_memq
, rb_vm_page_scancmp
,
2537 pmap_object_init_pt_callback
, &info
);
2538 lwkt_reltoken(&vm_token
);
2544 pmap_object_init_pt_callback(vm_page_t p
, void *data
)
2546 struct rb_vm_page_scan_info
*info
= data
;
2547 vm_pindex_t rel_index
;
2549 * don't allow an madvise to blow away our really
2550 * free pages allocating pv entries.
2552 if ((info
->limit
& MAP_PREFAULT_MADVISE
) &&
2553 vmstats
.v_free_count
< vmstats
.v_free_reserved
) {
2556 if (((p
->valid
& VM_PAGE_BITS_ALL
) == VM_PAGE_BITS_ALL
) &&
2557 (p
->busy
== 0) && (p
->flags
& (PG_BUSY
| PG_FICTITIOUS
)) == 0) {
2558 if ((p
->queue
- p
->pc
) == PQ_CACHE
)
2559 vm_page_deactivate(p
);
2561 rel_index
= p
->pindex
- info
->start_pindex
;
2562 pmap_enter_quick(info
->pmap
,
2563 info
->addr
+ x86_64_ptob(rel_index
), p
);
2570 * Return TRUE if the pmap is in shape to trivially
2571 * pre-fault the specified address.
2573 * Returns FALSE if it would be non-trivial or if a
2574 * pte is already loaded into the slot.
2579 pmap_prefault_ok(pmap_t pmap
, vm_offset_t addr
)
2585 lwkt_gettoken(&vm_token
);
2586 pde
= pmap_pde(pmap
, addr
);
2587 if (pde
== NULL
|| *pde
== 0) {
2590 pte
= pmap_pde_to_pte(pde
, addr
);
2591 ret
= (*pte
) ? 0 : 1;
2593 lwkt_reltoken(&vm_token
);
2598 * Change the wiring attribute for a map/virtual-address pair.
2600 * The mapping must already exist in the pmap.
2601 * No other requirements.
2604 pmap_change_wiring(pmap_t pmap
, vm_offset_t va
, boolean_t wired
)
2611 lwkt_gettoken(&vm_token
);
2612 pte
= pmap_pte(pmap
, va
);
2614 if (wired
&& !pmap_pte_w(pte
))
2615 pmap
->pm_stats
.wired_count
++;
2616 else if (!wired
&& pmap_pte_w(pte
))
2617 pmap
->pm_stats
.wired_count
--;
2620 * Wiring is not a hardware characteristic so there is no need to
2621 * invalidate TLB. However, in an SMP environment we must use
2622 * a locked bus cycle to update the pte (if we are not using
2623 * the pmap_inval_*() API that is)... it's ok to do this for simple
2627 atomic_set_long(pte
, VPTE_WIRED
);
2629 atomic_clear_long(pte
, VPTE_WIRED
);
2630 lwkt_reltoken(&vm_token
);
2634 * Copy the range specified by src_addr/len
2635 * from the source map to the range dst_addr/len
2636 * in the destination map.
2638 * This routine is only advisory and need not do anything.
2641 pmap_copy(pmap_t dst_pmap
, pmap_t src_pmap
, vm_offset_t dst_addr
,
2642 vm_size_t len
, vm_offset_t src_addr
)
2645 * XXX BUGGY. Amoung other things srcmpte is assumed to remain
2646 * valid through blocking calls, and that's just not going to
2657 * Zero the specified physical page.
2659 * This function may be called from an interrupt and no locking is
2663 pmap_zero_page(vm_paddr_t phys
)
2665 vm_offset_t va
= PHYS_TO_DMAP(phys
);
2667 bzero((void *)va
, PAGE_SIZE
);
2671 * pmap_page_assertzero:
2673 * Assert that a page is empty, panic if it isn't.
2676 pmap_page_assertzero(vm_paddr_t phys
)
2681 vm_offset_t virt
= PHYS_TO_DMAP(phys
);
2683 for (i
= 0; i
< PAGE_SIZE
; i
+= sizeof(int)) {
2684 if (*(int *)((char *)virt
+ i
) != 0) {
2685 panic("pmap_page_assertzero() @ %p not zero!\n",
2695 * Zero part of a physical page by mapping it into memory and clearing
2696 * its contents with bzero.
2698 * off and size may not cover an area beyond a single hardware page.
2701 pmap_zero_page_area(vm_paddr_t phys
, int off
, int size
)
2704 vm_offset_t virt
= PHYS_TO_DMAP(phys
);
2705 bzero((char *)virt
+ off
, size
);
2712 * Copy the physical page from the source PA to the target PA.
2713 * This function may be called from an interrupt. No locking
2717 pmap_copy_page(vm_paddr_t src
, vm_paddr_t dst
)
2719 vm_offset_t src_virt
, dst_virt
;
2722 src_virt
= PHYS_TO_DMAP(src
);
2723 dst_virt
= PHYS_TO_DMAP(dst
);
2724 bcopy((void *)src_virt
, (void *)dst_virt
, PAGE_SIZE
);
2729 * pmap_copy_page_frag:
2731 * Copy the physical page from the source PA to the target PA.
2732 * This function may be called from an interrupt. No locking
2736 pmap_copy_page_frag(vm_paddr_t src
, vm_paddr_t dst
, size_t bytes
)
2738 vm_offset_t src_virt
, dst_virt
;
2741 src_virt
= PHYS_TO_DMAP(src
);
2742 dst_virt
= PHYS_TO_DMAP(dst
);
2743 bcopy((char *)src_virt
+ (src
& PAGE_MASK
),
2744 (char *)dst_virt
+ (dst
& PAGE_MASK
),
2750 * Returns true if the pmap's pv is one of the first 16 pvs linked to
2751 * from this page. This count may be changed upwards or downwards
2752 * in the future; it is only necessary that true be returned for a small
2753 * subset of pmaps for proper page aging.
2755 * No other requirements.
2758 pmap_page_exists_quick(pmap_t pmap
, vm_page_t m
)
2763 if (!pmap_initialized
|| (m
->flags
& PG_FICTITIOUS
))
2767 lwkt_gettoken(&vm_token
);
2769 TAILQ_FOREACH(pv
, &m
->md
.pv_list
, pv_list
) {
2770 if (pv
->pv_pmap
== pmap
) {
2771 lwkt_reltoken(&vm_token
);
2779 lwkt_reltoken(&vm_token
);
2785 * Remove all pages from specified address space this aids process
2786 * exit speeds. Also, this code is special cased for current
2787 * process only, but can have the more generic (and slightly slower)
2788 * mode enabled. This is much faster than pmap_remove in the case
2789 * of running down an entire address space.
2791 * No other requirements.
2794 pmap_remove_pages(pmap_t pmap
, vm_offset_t sva
, vm_offset_t eva
)
2796 pt_entry_t
*pte
, tpte
;
2799 int save_generation
;
2802 lwkt_gettoken(&vm_token
);
2803 for (pv
= TAILQ_FIRST(&pmap
->pm_pvlist
); pv
; pv
= npv
) {
2804 if (pv
->pv_va
>= eva
|| pv
->pv_va
< sva
) {
2805 npv
= TAILQ_NEXT(pv
, pv_plist
);
2809 KKASSERT(pmap
== pv
->pv_pmap
);
2811 pte
= pmap_pte(pmap
, pv
->pv_va
);
2814 * We cannot remove wired pages from a process' mapping
2817 if (*pte
& VPTE_WIRED
) {
2818 npv
= TAILQ_NEXT(pv
, pv_plist
);
2821 tpte
= pmap_inval_loadandclear(pte
, pmap
, pv
->pv_va
);
2823 m
= PHYS_TO_VM_PAGE(tpte
& VPTE_FRAME
);
2825 KASSERT(m
< &vm_page_array
[vm_page_array_size
],
2826 ("pmap_remove_pages: bad tpte %lx", tpte
));
2828 KKASSERT(pmap
->pm_stats
.resident_count
> 0);
2829 --pmap
->pm_stats
.resident_count
;
2832 * Update the vm_page_t clean and reference bits.
2834 if (tpte
& VPTE_M
) {
2838 npv
= TAILQ_NEXT(pv
, pv_plist
);
2839 TAILQ_REMOVE(&pmap
->pm_pvlist
, pv
, pv_plist
);
2840 save_generation
= ++pmap
->pm_generation
;
2842 m
->md
.pv_list_count
--;
2843 m
->object
->agg_pv_list_count
--;
2844 TAILQ_REMOVE(&m
->md
.pv_list
, pv
, pv_list
);
2845 if (TAILQ_EMPTY(&m
->md
.pv_list
))
2846 vm_page_flag_clear(m
, PG_MAPPED
| PG_WRITEABLE
);
2848 pmap_unuse_pt(pmap
, pv
->pv_va
, pv
->pv_ptem
);
2852 * Restart the scan if we blocked during the unuse or free
2853 * calls and other removals were made.
2855 if (save_generation
!= pmap
->pm_generation
) {
2856 kprintf("Warning: pmap_remove_pages race-A avoided\n");
2857 npv
= TAILQ_FIRST(&pmap
->pm_pvlist
);
2860 lwkt_reltoken(&vm_token
);
2865 * pmap_testbit tests bits in active mappings of a VM page.
2868 pmap_testbit(vm_page_t m
, int bit
)
2873 if (!pmap_initialized
|| (m
->flags
& PG_FICTITIOUS
))
2876 if (TAILQ_FIRST(&m
->md
.pv_list
) == NULL
)
2881 TAILQ_FOREACH(pv
, &m
->md
.pv_list
, pv_list
) {
2883 * if the bit being tested is the modified bit, then
2884 * mark clean_map and ptes as never
2887 if (bit
& (VPTE_A
|VPTE_M
)) {
2888 if (!pmap_track_modified(pv
->pv_pmap
, pv
->pv_va
))
2892 #if defined(PMAP_DIAGNOSTIC)
2893 if (pv
->pv_pmap
== NULL
) {
2894 kprintf("Null pmap (tb) at va: 0x%lx\n", pv
->pv_va
);
2898 pte
= pmap_pte(pv
->pv_pmap
, pv
->pv_va
);
2909 * This routine is used to clear bits in ptes. Certain bits require special
2910 * handling, in particular (on virtual kernels) the VPTE_M (modify) bit.
2912 * This routine is only called with certain VPTE_* bit combinations.
2914 static __inline
void
2915 pmap_clearbit(vm_page_t m
, int bit
)
2921 if (!pmap_initialized
|| (m
->flags
& PG_FICTITIOUS
))
2927 * Loop over all current mappings setting/clearing as appropos If
2928 * setting RO do we need to clear the VAC?
2930 TAILQ_FOREACH(pv
, &m
->md
.pv_list
, pv_list
) {
2932 * don't write protect pager mappings
2934 if (bit
== VPTE_W
) {
2935 if (!pmap_track_modified(pv
->pv_pmap
, pv
->pv_va
))
2939 #if defined(PMAP_DIAGNOSTIC)
2940 if (pv
->pv_pmap
== NULL
) {
2941 kprintf("Null pmap (cb) at va: 0x%lx\n", pv
->pv_va
);
2947 * Careful here. We can use a locked bus instruction to
2948 * clear VPTE_A or VPTE_M safely but we need to synchronize
2949 * with the target cpus when we mess with VPTE_W.
2951 * On virtual kernels we must force a new fault-on-write
2952 * in the real kernel if we clear the Modify bit ourselves,
2953 * otherwise the real kernel will not get a new fault and
2954 * will never set our Modify bit again.
2956 pte
= pmap_pte(pv
->pv_pmap
, pv
->pv_va
);
2958 if (bit
== VPTE_W
) {
2960 * We must also clear VPTE_M when clearing
2963 pbits
= pmap_clean_pte(pte
, pv
->pv_pmap
,
2967 } else if (bit
== VPTE_M
) {
2969 * We do not have to make the page read-only
2970 * when clearing the Modify bit. The real
2971 * kernel will make the real PTE read-only
2972 * or otherwise detect the write and set
2973 * our VPTE_M again simply by us invalidating
2974 * the real kernel VA for the pmap (as we did
2975 * above). This allows the real kernel to
2976 * handle the write fault without forwarding
2979 atomic_clear_long(pte
, VPTE_M
);
2980 } else if ((bit
& (VPTE_W
|VPTE_M
)) == (VPTE_W
|VPTE_M
)) {
2982 * We've been asked to clear W & M, I guess
2983 * the caller doesn't want us to update
2984 * the dirty status of the VM page.
2986 pmap_clean_pte(pte
, pv
->pv_pmap
, pv
->pv_va
);
2989 * We've been asked to clear bits that do
2990 * not interact with hardware.
2992 atomic_clear_long(pte
, bit
);
3000 * Lower the permission for all mappings to a given page.
3002 * No other requirements.
3005 pmap_page_protect(vm_page_t m
, vm_prot_t prot
)
3007 /* JG NX support? */
3008 if ((prot
& VM_PROT_WRITE
) == 0) {
3009 lwkt_gettoken(&vm_token
);
3010 if (prot
& (VM_PROT_READ
| VM_PROT_EXECUTE
)) {
3011 pmap_clearbit(m
, VPTE_W
);
3012 vm_page_flag_clear(m
, PG_WRITEABLE
);
3016 lwkt_reltoken(&vm_token
);
3021 pmap_phys_address(vm_pindex_t ppn
)
3023 return (x86_64_ptob(ppn
));
3027 * Return a count of reference bits for a page, clearing those bits.
3028 * It is not necessary for every reference bit to be cleared, but it
3029 * is necessary that 0 only be returned when there are truly no
3030 * reference bits set.
3032 * XXX: The exact number of bits to check and clear is a matter that
3033 * should be tested and standardized at some point in the future for
3034 * optimal aging of shared pages.
3036 * No other requirements.
3039 pmap_ts_referenced(vm_page_t m
)
3041 pv_entry_t pv
, pvf
, pvn
;
3045 if (!pmap_initialized
|| (m
->flags
& PG_FICTITIOUS
))
3049 lwkt_gettoken(&vm_token
);
3051 if ((pv
= TAILQ_FIRST(&m
->md
.pv_list
)) != NULL
) {
3056 pvn
= TAILQ_NEXT(pv
, pv_list
);
3058 TAILQ_REMOVE(&m
->md
.pv_list
, pv
, pv_list
);
3060 TAILQ_INSERT_TAIL(&m
->md
.pv_list
, pv
, pv_list
);
3062 if (!pmap_track_modified(pv
->pv_pmap
, pv
->pv_va
))
3065 pte
= pmap_pte(pv
->pv_pmap
, pv
->pv_va
);
3067 if (pte
&& (*pte
& VPTE_A
)) {
3069 atomic_clear_long(pte
, VPTE_A
);
3071 atomic_clear_long_nonlocked(pte
, VPTE_A
);
3078 } while ((pv
= pvn
) != NULL
&& pv
!= pvf
);
3080 lwkt_reltoken(&vm_token
);
3087 * Return whether or not the specified physical page was modified
3088 * in any physical maps.
3090 * No other requirements.
3093 pmap_is_modified(vm_page_t m
)
3097 lwkt_gettoken(&vm_token
);
3098 res
= pmap_testbit(m
, VPTE_M
);
3099 lwkt_reltoken(&vm_token
);
3104 * Clear the modify bits on the specified physical page.
3106 * No other requirements.
3109 pmap_clear_modify(vm_page_t m
)
3111 lwkt_gettoken(&vm_token
);
3112 pmap_clearbit(m
, VPTE_M
);
3113 lwkt_reltoken(&vm_token
);
3117 * Clear the reference bit on the specified physical page.
3119 * No other requirements.
3122 pmap_clear_reference(vm_page_t m
)
3124 lwkt_gettoken(&vm_token
);
3125 pmap_clearbit(m
, VPTE_A
);
3126 lwkt_reltoken(&vm_token
);
3130 * Miscellaneous support routines follow
3134 i386_protection_init(void)
3138 kp
= protection_codes
;
3139 for (prot
= 0; prot
< 8; prot
++) {
3140 if (prot
& VM_PROT_READ
)
3142 if (prot
& VM_PROT_WRITE
)
3144 if (prot
& VM_PROT_EXECUTE
)
3151 * Perform the pmap work for mincore
3153 * No other requirements.
3156 pmap_mincore(pmap_t pmap
, vm_offset_t addr
)
3158 pt_entry_t
*ptep
, pte
;
3162 lwkt_gettoken(&vm_token
);
3163 ptep
= pmap_pte(pmap
, addr
);
3165 if (ptep
&& (pte
= *ptep
) != 0) {
3168 val
= MINCORE_INCORE
;
3169 if ((pte
& VPTE_MANAGED
) == 0)
3172 pa
= pte
& VPTE_FRAME
;
3174 m
= PHYS_TO_VM_PAGE(pa
);
3180 val
|= MINCORE_MODIFIED
|MINCORE_MODIFIED_OTHER
;
3182 * Modified by someone
3184 else if (m
->dirty
|| pmap_is_modified(m
))
3185 val
|= MINCORE_MODIFIED_OTHER
;
3190 val
|= MINCORE_REFERENCED
|MINCORE_REFERENCED_OTHER
;
3193 * Referenced by someone
3195 else if ((m
->flags
& PG_REFERENCED
) || pmap_ts_referenced(m
)) {
3196 val
|= MINCORE_REFERENCED_OTHER
;
3197 vm_page_flag_set(m
, PG_REFERENCED
);
3201 lwkt_reltoken(&vm_token
);
3206 * Replace p->p_vmspace with a new one. If adjrefs is non-zero the new
3207 * vmspace will be ref'd and the old one will be deref'd.
3210 pmap_replacevm(struct proc
*p
, struct vmspace
*newvm
, int adjrefs
)
3212 struct vmspace
*oldvm
;
3216 oldvm
= p
->p_vmspace
;
3217 if (oldvm
!= newvm
) {
3218 p
->p_vmspace
= newvm
;
3219 KKASSERT(p
->p_nthreads
== 1);
3220 lp
= RB_ROOT(&p
->p_lwp_tree
);
3221 pmap_setlwpvm(lp
, newvm
);
3223 sysref_get(&newvm
->vm_sysref
);
3224 sysref_put(&oldvm
->vm_sysref
);
3231 * Set the vmspace for a LWP. The vmspace is almost universally set the
3232 * same as the process vmspace, but virtual kernels need to swap out contexts
3233 * on a per-lwp basis.
3236 pmap_setlwpvm(struct lwp
*lp
, struct vmspace
*newvm
)
3238 struct vmspace
*oldvm
;
3242 oldvm
= lp
->lwp_vmspace
;
3244 if (oldvm
!= newvm
) {
3245 lp
->lwp_vmspace
= newvm
;
3246 if (curthread
->td_lwp
== lp
) {
3247 pmap
= vmspace_pmap(newvm
);
3249 atomic_set_int(&pmap
->pm_active
, 1 << mycpu
->gd_cpuid
);
3251 pmap
->pm_active
|= 1;
3253 #if defined(SWTCH_OPTIM_STATS)
3256 pmap
= vmspace_pmap(oldvm
);
3258 atomic_clear_int(&pmap
->pm_active
,
3259 1 << mycpu
->gd_cpuid
);
3261 pmap
->pm_active
&= ~1;
3269 pmap_addr_hint(vm_object_t obj
, vm_offset_t addr
, vm_size_t size
)
3272 if ((obj
== NULL
) || (size
< NBPDR
) || (obj
->type
!= OBJT_DEVICE
)) {
3276 addr
= (addr
+ (NBPDR
- 1)) & ~(NBPDR
- 1);
3281 * Used by kmalloc/kfree, page already exists at va
3284 pmap_kvtom(vm_offset_t va
)
3288 KKASSERT(va
>= KvaStart
&& va
< KvaEnd
);
3290 return(PHYS_TO_VM_PAGE(*ptep
& PG_FRAME
));