4 * Copyright (c) 1991, 1993
5 * The Regents of the University of California. All rights reserved.
7 * This code is derived from software contributed to Berkeley by
8 * The Mach Operating System project at Carnegie-Mellon University.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * from: @(#)vm_map.c 8.3 (Berkeley) 1/12/94
41 * Copyright (c) 1987, 1990 Carnegie-Mellon University.
42 * All rights reserved.
44 * Authors: Avadis Tevanian, Jr., Michael Wayne Young
46 * Permission to use, copy, modify and distribute this software and
47 * its documentation is hereby granted, provided that both the copyright
48 * notice and this permission notice appear in all copies of the
49 * software, derivative works or modified versions, and any portions
50 * thereof, and that both notices appear in supporting documentation.
52 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
53 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
54 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
56 * Carnegie Mellon requests users of this software to return to
58 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
59 * School of Computer Science
60 * Carnegie Mellon University
61 * Pittsburgh PA 15213-3890
63 * any improvements or extensions that they make and grant Carnegie the
64 * rights to redistribute these changes.
66 * $FreeBSD: src/sys/vm/vm_map.c,v 1.187.2.19 2003/05/27 00:47:02 alc Exp $
67 * $DragonFly: src/sys/vm/vm_map.c,v 1.56 2007/04/29 18:25:41 dillon Exp $
71 * Virtual memory mapping module.
74 #include <sys/param.h>
75 #include <sys/systm.h>
76 #include <sys/kernel.h>
79 #include <sys/vmmeter.h>
81 #include <sys/vnode.h>
82 #include <sys/resourcevar.h>
85 #include <sys/malloc.h>
88 #include <vm/vm_param.h>
90 #include <vm/vm_map.h>
91 #include <vm/vm_page.h>
92 #include <vm/vm_object.h>
93 #include <vm/vm_pager.h>
94 #include <vm/vm_kern.h>
95 #include <vm/vm_extern.h>
96 #include <vm/swap_pager.h>
97 #include <vm/vm_zone.h>
99 #include <sys/thread2.h>
100 #include <sys/sysref2.h>
103 * Virtual memory maps provide for the mapping, protection, and sharing
104 * of virtual memory objects. In addition, this module provides for an
105 * efficient virtual copy of memory from one map to another.
107 * Synchronization is required prior to most operations.
109 * Maps consist of an ordered doubly-linked list of simple entries.
110 * A hint and a RB tree is used to speed-up lookups.
112 * Callers looking to modify maps specify start/end addresses which cause
113 * the related map entry to be clipped if necessary, and then later
114 * recombined if the pieces remained compatible.
116 * Virtual copy operations are performed by copying VM object references
117 * from one map to another, and then marking both regions as copy-on-write.
119 static void vmspace_terminate(struct vmspace
*vm
);
120 static void vmspace_lock(struct vmspace
*vm
);
121 static void vmspace_unlock(struct vmspace
*vm
);
122 static void vmspace_dtor(void *obj
, void *private);
124 MALLOC_DEFINE(M_VMSPACE
, "vmspace", "vmspace objcache backingstore");
126 struct sysref_class vmspace_sysref_class
= {
129 .proto
= SYSREF_PROTO_VMSPACE
,
130 .offset
= offsetof(struct vmspace
, vm_sysref
),
131 .objsize
= sizeof(struct vmspace
),
133 .flags
= SRC_MANAGEDINIT
,
134 .dtor
= vmspace_dtor
,
136 .terminate
= (sysref_terminate_func_t
)vmspace_terminate
,
137 .lock
= (sysref_lock_func_t
)vmspace_lock
,
138 .unlock
= (sysref_lock_func_t
)vmspace_unlock
144 static struct vm_zone mapentzone_store
, mapzone_store
;
145 static vm_zone_t mapentzone
, mapzone
;
146 static struct vm_object mapentobj
, mapobj
;
148 static struct vm_map_entry map_entry_init
[MAX_MAPENT
];
149 static struct vm_map_entry cpu_map_entry_init
[MAXCPU
][VMEPERCPU
];
150 static struct vm_map map_init
[MAX_KMAP
];
152 static void vm_map_entry_shadow(vm_map_entry_t entry
);
153 static vm_map_entry_t
vm_map_entry_create(vm_map_t map
, int *);
154 static void vm_map_entry_dispose (vm_map_t map
, vm_map_entry_t entry
, int *);
155 static void _vm_map_clip_end (vm_map_t
, vm_map_entry_t
, vm_offset_t
, int *);
156 static void _vm_map_clip_start (vm_map_t
, vm_map_entry_t
, vm_offset_t
, int *);
157 static void vm_map_entry_delete (vm_map_t
, vm_map_entry_t
, int *);
158 static void vm_map_entry_unwire (vm_map_t
, vm_map_entry_t
);
159 static void vm_map_copy_entry (vm_map_t
, vm_map_t
, vm_map_entry_t
,
161 static void vm_map_split (vm_map_entry_t
);
162 static void vm_map_unclip_range (vm_map_t map
, vm_map_entry_t start_entry
, vm_offset_t start
, vm_offset_t end
, int *count
, int flags
);
165 * Initialize the vm_map module. Must be called before any other vm_map
168 * Map and entry structures are allocated from the general purpose
169 * memory pool with some exceptions:
171 * - The kernel map is allocated statically.
172 * - Initial kernel map entries are allocated out of a static pool.
174 * These restrictions are necessary since malloc() uses the
175 * maps and requires map entries.
177 * Called from the low level boot code only.
182 mapzone
= &mapzone_store
;
183 zbootinit(mapzone
, "MAP", sizeof (struct vm_map
),
185 mapentzone
= &mapentzone_store
;
186 zbootinit(mapentzone
, "MAP ENTRY", sizeof (struct vm_map_entry
),
187 map_entry_init
, MAX_MAPENT
);
191 * Called prior to any vmspace allocations.
193 * Called from the low level boot code only.
198 zinitna(mapentzone
, &mapentobj
, NULL
, 0, 0,
199 ZONE_USE_RESERVE
| ZONE_SPECIAL
, 1);
200 zinitna(mapzone
, &mapobj
, NULL
, 0, 0, 0, 1);
207 * Red black tree functions
209 * The caller must hold the related map lock.
211 static int rb_vm_map_compare(vm_map_entry_t a
, vm_map_entry_t b
);
212 RB_GENERATE(vm_map_rb_tree
, vm_map_entry
, rb_entry
, rb_vm_map_compare
);
214 /* a->start is address, and the only field has to be initialized */
216 rb_vm_map_compare(vm_map_entry_t a
, vm_map_entry_t b
)
218 if (a
->start
< b
->start
)
220 else if (a
->start
> b
->start
)
226 * Allocate a vmspace structure, including a vm_map and pmap.
227 * Initialize numerous fields. While the initial allocation is zerod,
228 * subsequence reuse from the objcache leaves elements of the structure
229 * intact (particularly the pmap), so portions must be zerod.
231 * The structure is not considered activated until we call sysref_activate().
236 vmspace_alloc(vm_offset_t min
, vm_offset_t max
)
240 lwkt_gettoken(&vmspace_token
);
241 vm
= sysref_alloc(&vmspace_sysref_class
);
242 bzero(&vm
->vm_startcopy
,
243 (char *)&vm
->vm_endcopy
- (char *)&vm
->vm_startcopy
);
244 vm_map_init(&vm
->vm_map
, min
, max
, NULL
);
245 pmap_pinit(vmspace_pmap(vm
)); /* (some fields reused) */
246 vm
->vm_map
.pmap
= vmspace_pmap(vm
); /* XXX */
248 vm
->vm_exitingcnt
= 0;
249 cpu_vmspace_alloc(vm
);
250 sysref_activate(&vm
->vm_sysref
);
251 lwkt_reltoken(&vmspace_token
);
257 * dtor function - Some elements of the pmap are retained in the
258 * free-cached vmspaces to improve performance. We have to clean them up
259 * here before returning the vmspace to the memory pool.
264 vmspace_dtor(void *obj
, void *private)
266 struct vmspace
*vm
= obj
;
268 pmap_puninit(vmspace_pmap(vm
));
272 * Called in two cases:
274 * (1) When the last sysref is dropped, but exitingcnt might still be
277 * (2) When there are no sysrefs (i.e. refcnt is negative) left and the
278 * exitingcnt becomes zero
280 * sysref will not scrap the object until we call sysref_put() once more
281 * after the last ref has been dropped.
283 * Interlocked by the sysref API.
286 vmspace_terminate(struct vmspace
*vm
)
291 * If exitingcnt is non-zero we can't get rid of the entire vmspace
292 * yet, but we can scrap user memory.
294 lwkt_gettoken(&vmspace_token
);
295 if (vm
->vm_exitingcnt
) {
297 pmap_remove_pages(vmspace_pmap(vm
), VM_MIN_USER_ADDRESS
,
298 VM_MAX_USER_ADDRESS
);
299 vm_map_remove(&vm
->vm_map
, VM_MIN_USER_ADDRESS
,
300 VM_MAX_USER_ADDRESS
);
301 lwkt_reltoken(&vmspace_token
);
304 cpu_vmspace_free(vm
);
307 * Make sure any SysV shm is freed, it might not have in
312 KKASSERT(vm
->vm_upcalls
== NULL
);
315 * Lock the map, to wait out all other references to it.
316 * Delete all of the mappings and pages they hold, then call
317 * the pmap module to reclaim anything left.
319 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
320 vm_map_lock(&vm
->vm_map
);
321 vm_map_delete(&vm
->vm_map
, vm
->vm_map
.min_offset
,
322 vm
->vm_map
.max_offset
, &count
);
323 vm_map_unlock(&vm
->vm_map
);
324 vm_map_entry_release(count
);
326 pmap_release(vmspace_pmap(vm
));
327 sysref_put(&vm
->vm_sysref
);
328 lwkt_reltoken(&vmspace_token
);
332 * vmspaces are not currently locked.
335 vmspace_lock(struct vmspace
*vm __unused
)
340 vmspace_unlock(struct vmspace
*vm __unused
)
345 * This is called during exit indicating that the vmspace is no
346 * longer in used by an exiting process, but the process has not yet
352 vmspace_exitbump(struct vmspace
*vm
)
354 lwkt_gettoken(&vmspace_token
);
356 lwkt_reltoken(&vmspace_token
);
360 * This is called in the wait*() handling code. The vmspace can be terminated
361 * after the last wait is finished using it.
366 vmspace_exitfree(struct proc
*p
)
370 lwkt_gettoken(&vmspace_token
);
374 if (--vm
->vm_exitingcnt
== 0 && sysref_isinactive(&vm
->vm_sysref
))
375 vmspace_terminate(vm
);
376 lwkt_reltoken(&vmspace_token
);
380 * Swap useage is determined by taking the proportional swap used by
381 * VM objects backing the VM map. To make up for fractional losses,
382 * if the VM object has any swap use at all the associated map entries
383 * count for at least 1 swap page.
388 vmspace_swap_count(struct vmspace
*vmspace
)
390 vm_map_t map
= &vmspace
->vm_map
;
396 lwkt_gettoken(&vmspace_token
);
397 for (cur
= map
->header
.next
; cur
!= &map
->header
; cur
= cur
->next
) {
398 switch(cur
->maptype
) {
399 case VM_MAPTYPE_NORMAL
:
400 case VM_MAPTYPE_VPAGETABLE
:
401 if ((object
= cur
->object
.vm_object
) == NULL
)
403 if (object
->swblock_count
) {
404 n
= (cur
->end
- cur
->start
) / PAGE_SIZE
;
405 count
+= object
->swblock_count
*
406 SWAP_META_PAGES
* n
/ object
->size
+ 1;
413 lwkt_reltoken(&vmspace_token
);
418 * Calculate the approximate number of anonymous pages in use by
419 * this vmspace. To make up for fractional losses, we count each
420 * VM object as having at least 1 anonymous page.
425 vmspace_anonymous_count(struct vmspace
*vmspace
)
427 vm_map_t map
= &vmspace
->vm_map
;
432 lwkt_gettoken(&vmspace_token
);
433 for (cur
= map
->header
.next
; cur
!= &map
->header
; cur
= cur
->next
) {
434 switch(cur
->maptype
) {
435 case VM_MAPTYPE_NORMAL
:
436 case VM_MAPTYPE_VPAGETABLE
:
437 if ((object
= cur
->object
.vm_object
) == NULL
)
439 if (object
->type
!= OBJT_DEFAULT
&&
440 object
->type
!= OBJT_SWAP
) {
443 count
+= object
->resident_page_count
;
449 lwkt_reltoken(&vmspace_token
);
454 * Creates and returns a new empty VM map with the given physical map
455 * structure, and having the given lower and upper address bounds.
460 vm_map_create(vm_map_t result
, pmap_t pmap
, vm_offset_t min
, vm_offset_t max
)
463 result
= zalloc(mapzone
);
464 vm_map_init(result
, min
, max
, pmap
);
469 * Initialize an existing vm_map structure such as that in the vmspace
470 * structure. The pmap is initialized elsewhere.
475 vm_map_init(struct vm_map
*map
, vm_offset_t min
, vm_offset_t max
, pmap_t pmap
)
477 map
->header
.next
= map
->header
.prev
= &map
->header
;
478 RB_INIT(&map
->rb_root
);
483 map
->min_offset
= min
;
484 map
->max_offset
= max
;
486 map
->first_free
= &map
->header
;
487 map
->hint
= &map
->header
;
489 lockinit(&map
->lock
, "thrd_sleep", 0, 0);
493 * Shadow the vm_map_entry's object. This typically needs to be done when
494 * a write fault is taken on an entry which had previously been cloned by
495 * fork(). The shared object (which might be NULL) must become private so
496 * we add a shadow layer above it.
498 * Object allocation for anonymous mappings is defered as long as possible.
499 * When creating a shadow, however, the underlying object must be instantiated
500 * so it can be shared.
502 * If the map segment is governed by a virtual page table then it is
503 * possible to address offsets beyond the mapped area. Just allocate
504 * a maximally sized object for this case.
506 * The vm_map must be exclusively locked.
507 * No other requirements.
511 vm_map_entry_shadow(vm_map_entry_t entry
)
513 if (entry
->maptype
== VM_MAPTYPE_VPAGETABLE
) {
514 vm_object_shadow(&entry
->object
.vm_object
, &entry
->offset
,
515 0x7FFFFFFF); /* XXX */
517 vm_object_shadow(&entry
->object
.vm_object
, &entry
->offset
,
518 atop(entry
->end
- entry
->start
));
520 entry
->eflags
&= ~MAP_ENTRY_NEEDS_COPY
;
524 * Allocate an object for a vm_map_entry.
526 * Object allocation for anonymous mappings is defered as long as possible.
527 * This function is called when we can defer no longer, generally when a map
528 * entry might be split or forked or takes a page fault.
530 * If the map segment is governed by a virtual page table then it is
531 * possible to address offsets beyond the mapped area. Just allocate
532 * a maximally sized object for this case.
534 * The vm_map must be exclusively locked.
535 * No other requirements.
538 vm_map_entry_allocate_object(vm_map_entry_t entry
)
542 if (entry
->maptype
== VM_MAPTYPE_VPAGETABLE
) {
543 obj
= vm_object_allocate(OBJT_DEFAULT
, 0x7FFFFFFF); /* XXX */
545 obj
= vm_object_allocate(OBJT_DEFAULT
,
546 atop(entry
->end
- entry
->start
));
548 entry
->object
.vm_object
= obj
;
553 * Set an initial negative count so the first attempt to reserve
554 * space preloads a bunch of vm_map_entry's for this cpu. Also
555 * pre-allocate 2 vm_map_entries which will be needed by zalloc() to
556 * map a new page for vm_map_entry structures. SMP systems are
557 * particularly sensitive.
559 * This routine is called in early boot so we cannot just call
560 * vm_map_entry_reserve().
562 * Called from the low level boot code only (for each cpu)
565 vm_map_entry_reserve_cpu_init(globaldata_t gd
)
567 vm_map_entry_t entry
;
570 gd
->gd_vme_avail
-= MAP_RESERVE_COUNT
* 2;
571 entry
= &cpu_map_entry_init
[gd
->gd_cpuid
][0];
572 for (i
= 0; i
< VMEPERCPU
; ++i
, ++entry
) {
573 entry
->next
= gd
->gd_vme_base
;
574 gd
->gd_vme_base
= entry
;
579 * Reserves vm_map_entry structures so code later on can manipulate
580 * map_entry structures within a locked map without blocking trying
581 * to allocate a new vm_map_entry.
586 vm_map_entry_reserve(int count
)
588 struct globaldata
*gd
= mycpu
;
589 vm_map_entry_t entry
;
592 * Make sure we have enough structures in gd_vme_base to handle
593 * the reservation request.
596 while (gd
->gd_vme_avail
< count
) {
597 entry
= zalloc(mapentzone
);
598 entry
->next
= gd
->gd_vme_base
;
599 gd
->gd_vme_base
= entry
;
602 gd
->gd_vme_avail
-= count
;
609 * Releases previously reserved vm_map_entry structures that were not
610 * used. If we have too much junk in our per-cpu cache clean some of
616 vm_map_entry_release(int count
)
618 struct globaldata
*gd
= mycpu
;
619 vm_map_entry_t entry
;
622 gd
->gd_vme_avail
+= count
;
623 while (gd
->gd_vme_avail
> MAP_RESERVE_SLOP
) {
624 entry
= gd
->gd_vme_base
;
625 KKASSERT(entry
!= NULL
);
626 gd
->gd_vme_base
= entry
->next
;
629 zfree(mapentzone
, entry
);
636 * Reserve map entry structures for use in kernel_map itself. These
637 * entries have *ALREADY* been reserved on a per-cpu basis when the map
638 * was inited. This function is used by zalloc() to avoid a recursion
639 * when zalloc() itself needs to allocate additional kernel memory.
641 * This function works like the normal reserve but does not load the
642 * vm_map_entry cache (because that would result in an infinite
643 * recursion). Note that gd_vme_avail may go negative. This is expected.
645 * Any caller of this function must be sure to renormalize after
646 * potentially eating entries to ensure that the reserve supply
652 vm_map_entry_kreserve(int count
)
654 struct globaldata
*gd
= mycpu
;
657 gd
->gd_vme_avail
-= count
;
659 KASSERT(gd
->gd_vme_base
!= NULL
,
660 ("no reserved entries left, gd_vme_avail = %d\n",
666 * Release previously reserved map entries for kernel_map. We do not
667 * attempt to clean up like the normal release function as this would
668 * cause an unnecessary (but probably not fatal) deep procedure call.
673 vm_map_entry_krelease(int count
)
675 struct globaldata
*gd
= mycpu
;
678 gd
->gd_vme_avail
+= count
;
683 * Allocates a VM map entry for insertion. No entry fields are filled in.
685 * The entries should have previously been reserved. The reservation count
686 * is tracked in (*countp).
690 static vm_map_entry_t
691 vm_map_entry_create(vm_map_t map
, int *countp
)
693 struct globaldata
*gd
= mycpu
;
694 vm_map_entry_t entry
;
696 KKASSERT(*countp
> 0);
699 entry
= gd
->gd_vme_base
;
700 KASSERT(entry
!= NULL
, ("gd_vme_base NULL! count %d", *countp
));
701 gd
->gd_vme_base
= entry
->next
;
708 * Dispose of a vm_map_entry that is no longer being referenced.
713 vm_map_entry_dispose(vm_map_t map
, vm_map_entry_t entry
, int *countp
)
715 struct globaldata
*gd
= mycpu
;
717 KKASSERT(map
->hint
!= entry
);
718 KKASSERT(map
->first_free
!= entry
);
722 entry
->next
= gd
->gd_vme_base
;
723 gd
->gd_vme_base
= entry
;
729 * Insert/remove entries from maps.
731 * The related map must be exclusively locked.
732 * No other requirements.
734 * NOTE! We currently acquire the vmspace_token only to avoid races
735 * against the pageout daemon's calls to vmspace_*_count(), which
736 * are unable to safely lock the vm_map without potentially
740 vm_map_entry_link(vm_map_t map
,
741 vm_map_entry_t after_where
,
742 vm_map_entry_t entry
)
744 ASSERT_VM_MAP_LOCKED(map
);
746 lwkt_gettoken(&vmspace_token
);
748 entry
->prev
= after_where
;
749 entry
->next
= after_where
->next
;
750 entry
->next
->prev
= entry
;
751 after_where
->next
= entry
;
752 if (vm_map_rb_tree_RB_INSERT(&map
->rb_root
, entry
))
753 panic("vm_map_entry_link: dup addr map %p ent %p", map
, entry
);
754 lwkt_reltoken(&vmspace_token
);
758 vm_map_entry_unlink(vm_map_t map
,
759 vm_map_entry_t entry
)
764 ASSERT_VM_MAP_LOCKED(map
);
766 if (entry
->eflags
& MAP_ENTRY_IN_TRANSITION
) {
767 panic("vm_map_entry_unlink: attempt to mess with "
768 "locked entry! %p", entry
);
770 lwkt_gettoken(&vmspace_token
);
775 vm_map_rb_tree_RB_REMOVE(&map
->rb_root
, entry
);
777 lwkt_reltoken(&vmspace_token
);
781 * Finds the map entry containing (or immediately preceding) the specified
782 * address in the given map. The entry is returned in (*entry).
784 * The boolean result indicates whether the address is actually contained
787 * The related map must be locked.
788 * No other requirements.
791 vm_map_lookup_entry(vm_map_t map
, vm_offset_t address
, vm_map_entry_t
*entry
)
796 ASSERT_VM_MAP_LOCKED(map
);
799 * XXX TEMPORARILY DISABLED. For some reason our attempt to revive
800 * the hint code with the red-black lookup meets with system crashes
801 * and lockups. We do not yet know why.
803 * It is possible that the problem is related to the setting
804 * of the hint during map_entry deletion, in the code specified
805 * at the GGG comment later on in this file.
808 * Quickly check the cached hint, there's a good chance of a match.
810 if (map
->hint
!= &map
->header
) {
812 if (address
>= tmp
->start
&& address
< tmp
->end
) {
820 * Locate the record from the top of the tree. 'last' tracks the
821 * closest prior record and is returned if no match is found, which
822 * in binary tree terms means tracking the most recent right-branch
823 * taken. If there is no prior record, &map->header is returned.
826 tmp
= RB_ROOT(&map
->rb_root
);
829 if (address
>= tmp
->start
) {
830 if (address
< tmp
->end
) {
836 tmp
= RB_RIGHT(tmp
, rb_entry
);
838 tmp
= RB_LEFT(tmp
, rb_entry
);
846 * Inserts the given whole VM object into the target map at the specified
847 * address range. The object's size should match that of the address range.
849 * The map must be exclusively locked.
850 * The caller must have reserved sufficient vm_map_entry structures.
852 * If object is non-NULL, ref count must be bumped by caller
853 * prior to making call to account for the new entry.
856 vm_map_insert(vm_map_t map
, int *countp
,
857 vm_object_t object
, vm_ooffset_t offset
,
858 vm_offset_t start
, vm_offset_t end
,
859 vm_maptype_t maptype
,
860 vm_prot_t prot
, vm_prot_t max
,
863 vm_map_entry_t new_entry
;
864 vm_map_entry_t prev_entry
;
865 vm_map_entry_t temp_entry
;
866 vm_eflags_t protoeflags
;
868 ASSERT_VM_MAP_LOCKED(map
);
871 * Check that the start and end points are not bogus.
873 if ((start
< map
->min_offset
) || (end
> map
->max_offset
) ||
875 return (KERN_INVALID_ADDRESS
);
878 * Find the entry prior to the proposed starting address; if it's part
879 * of an existing entry, this range is bogus.
881 if (vm_map_lookup_entry(map
, start
, &temp_entry
))
882 return (KERN_NO_SPACE
);
884 prev_entry
= temp_entry
;
887 * Assert that the next entry doesn't overlap the end point.
890 if ((prev_entry
->next
!= &map
->header
) &&
891 (prev_entry
->next
->start
< end
))
892 return (KERN_NO_SPACE
);
896 if (cow
& MAP_COPY_ON_WRITE
)
897 protoeflags
|= MAP_ENTRY_COW
|MAP_ENTRY_NEEDS_COPY
;
899 if (cow
& MAP_NOFAULT
) {
900 protoeflags
|= MAP_ENTRY_NOFAULT
;
902 KASSERT(object
== NULL
,
903 ("vm_map_insert: paradoxical MAP_NOFAULT request"));
905 if (cow
& MAP_DISABLE_SYNCER
)
906 protoeflags
|= MAP_ENTRY_NOSYNC
;
907 if (cow
& MAP_DISABLE_COREDUMP
)
908 protoeflags
|= MAP_ENTRY_NOCOREDUMP
;
909 if (cow
& MAP_IS_STACK
)
910 protoeflags
|= MAP_ENTRY_STACK
;
914 * When object is non-NULL, it could be shared with another
915 * process. We have to set or clear OBJ_ONEMAPPING
918 if ((object
->ref_count
> 1) || (object
->shadow_count
!= 0)) {
919 vm_object_clear_flag(object
, OBJ_ONEMAPPING
);
922 else if ((prev_entry
!= &map
->header
) &&
923 (prev_entry
->eflags
== protoeflags
) &&
924 (prev_entry
->end
== start
) &&
925 (prev_entry
->wired_count
== 0) &&
926 prev_entry
->maptype
== maptype
&&
927 ((prev_entry
->object
.vm_object
== NULL
) ||
928 vm_object_coalesce(prev_entry
->object
.vm_object
,
929 OFF_TO_IDX(prev_entry
->offset
),
930 (vm_size_t
)(prev_entry
->end
- prev_entry
->start
),
931 (vm_size_t
)(end
- prev_entry
->end
)))) {
933 * We were able to extend the object. Determine if we
934 * can extend the previous map entry to include the
937 if ((prev_entry
->inheritance
== VM_INHERIT_DEFAULT
) &&
938 (prev_entry
->protection
== prot
) &&
939 (prev_entry
->max_protection
== max
)) {
940 map
->size
+= (end
- prev_entry
->end
);
941 prev_entry
->end
= end
;
942 vm_map_simplify_entry(map
, prev_entry
, countp
);
943 return (KERN_SUCCESS
);
947 * If we can extend the object but cannot extend the
948 * map entry, we have to create a new map entry. We
949 * must bump the ref count on the extended object to
950 * account for it. object may be NULL.
952 object
= prev_entry
->object
.vm_object
;
953 offset
= prev_entry
->offset
+
954 (prev_entry
->end
- prev_entry
->start
);
955 vm_object_reference(object
);
959 * NOTE: if conditionals fail, object can be NULL here. This occurs
960 * in things like the buffer map where we manage kva but do not manage
968 new_entry
= vm_map_entry_create(map
, countp
);
969 new_entry
->start
= start
;
970 new_entry
->end
= end
;
972 new_entry
->maptype
= maptype
;
973 new_entry
->eflags
= protoeflags
;
974 new_entry
->object
.vm_object
= object
;
975 new_entry
->offset
= offset
;
976 new_entry
->aux
.master_pde
= 0;
978 new_entry
->inheritance
= VM_INHERIT_DEFAULT
;
979 new_entry
->protection
= prot
;
980 new_entry
->max_protection
= max
;
981 new_entry
->wired_count
= 0;
984 * Insert the new entry into the list
987 vm_map_entry_link(map
, prev_entry
, new_entry
);
988 map
->size
+= new_entry
->end
- new_entry
->start
;
991 * Update the free space hint. Entries cannot overlap.
992 * An exact comparison is needed to avoid matching
993 * against the map->header.
995 if ((map
->first_free
== prev_entry
) &&
996 (prev_entry
->end
== new_entry
->start
)) {
997 map
->first_free
= new_entry
;
1002 * Temporarily removed to avoid MAP_STACK panic, due to
1003 * MAP_STACK being a huge hack. Will be added back in
1004 * when MAP_STACK (and the user stack mapping) is fixed.
1007 * It may be possible to simplify the entry
1009 vm_map_simplify_entry(map
, new_entry
, countp
);
1013 * Try to pre-populate the page table. Mappings governed by virtual
1014 * page tables cannot be prepopulated without a lot of work, so
1017 if ((cow
& (MAP_PREFAULT
|MAP_PREFAULT_PARTIAL
)) &&
1018 maptype
!= VM_MAPTYPE_VPAGETABLE
) {
1019 pmap_object_init_pt(map
->pmap
, start
, prot
,
1020 object
, OFF_TO_IDX(offset
), end
- start
,
1021 cow
& MAP_PREFAULT_PARTIAL
);
1024 return (KERN_SUCCESS
);
1028 * Find sufficient space for `length' bytes in the given map, starting at
1029 * `start'. Returns 0 on success, 1 on no space.
1031 * This function will returned an arbitrarily aligned pointer. If no
1032 * particular alignment is required you should pass align as 1. Note that
1033 * the map may return PAGE_SIZE aligned pointers if all the lengths used in
1034 * the map are a multiple of PAGE_SIZE, even if you pass a smaller align
1037 * 'align' should be a power of 2 but is not required to be.
1039 * The map must be exclusively locked.
1040 * No other requirements.
1043 vm_map_findspace(vm_map_t map
, vm_offset_t start
, vm_size_t length
,
1044 vm_size_t align
, int flags
, vm_offset_t
*addr
)
1046 vm_map_entry_t entry
, next
;
1048 vm_offset_t align_mask
;
1050 if (start
< map
->min_offset
)
1051 start
= map
->min_offset
;
1052 if (start
> map
->max_offset
)
1056 * If the alignment is not a power of 2 we will have to use
1057 * a mod/division, set align_mask to a special value.
1059 if ((align
| (align
- 1)) + 1 != (align
<< 1))
1060 align_mask
= (vm_offset_t
)-1;
1062 align_mask
= align
- 1;
1066 * Look for the first possible address; if there's already something
1067 * at this address, we have to start after it.
1069 if (start
== map
->min_offset
) {
1070 if ((entry
= map
->first_free
) != &map
->header
)
1075 if (vm_map_lookup_entry(map
, start
, &tmp
))
1081 * Look through the rest of the map, trying to fit a new region in the
1082 * gap between existing regions, or after the very last region.
1084 for (;; start
= (entry
= next
)->end
) {
1086 * Adjust the proposed start by the requested alignment,
1087 * be sure that we didn't wrap the address.
1089 if (align_mask
== (vm_offset_t
)-1)
1090 end
= ((start
+ align
- 1) / align
) * align
;
1092 end
= (start
+ align_mask
) & ~align_mask
;
1097 * Find the end of the proposed new region. Be sure we didn't
1098 * go beyond the end of the map, or wrap around the address.
1099 * Then check to see if this is the last entry or if the
1100 * proposed end fits in the gap between this and the next
1103 end
= start
+ length
;
1104 if (end
> map
->max_offset
|| end
< start
)
1109 * If the next entry's start address is beyond the desired
1110 * end address we may have found a good entry.
1112 * If the next entry is a stack mapping we do not map into
1113 * the stack's reserved space.
1115 * XXX continue to allow mapping into the stack's reserved
1116 * space if doing a MAP_STACK mapping inside a MAP_STACK
1117 * mapping, for backwards compatibility. But the caller
1118 * really should use MAP_STACK | MAP_TRYFIXED if they
1121 if (next
== &map
->header
)
1123 if (next
->start
>= end
) {
1124 if ((next
->eflags
& MAP_ENTRY_STACK
) == 0)
1126 if (flags
& MAP_STACK
)
1128 if (next
->start
- next
->aux
.avail_ssize
>= end
)
1133 if (map
== &kernel_map
) {
1135 if ((ksize
= round_page(start
+ length
)) > kernel_vm_end
) {
1136 pmap_growkernel(ksize
);
1145 * vm_map_find finds an unallocated region in the target address map with
1146 * the given length. The search is defined to be first-fit from the
1147 * specified address; the region found is returned in the same parameter.
1149 * If object is non-NULL, ref count must be bumped by caller
1150 * prior to making call to account for the new entry.
1152 * No requirements. This function will lock the map temporarily.
1155 vm_map_find(vm_map_t map
, vm_object_t object
, vm_ooffset_t offset
,
1156 vm_offset_t
*addr
, vm_size_t length
, vm_size_t align
,
1158 vm_maptype_t maptype
,
1159 vm_prot_t prot
, vm_prot_t max
,
1168 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
1171 if (vm_map_findspace(map
, start
, length
, align
, 0, addr
)) {
1173 vm_map_entry_release(count
);
1174 return (KERN_NO_SPACE
);
1178 result
= vm_map_insert(map
, &count
, object
, offset
,
1179 start
, start
+ length
,
1184 vm_map_entry_release(count
);
1190 * Simplify the given map entry by merging with either neighbor. This
1191 * routine also has the ability to merge with both neighbors.
1193 * This routine guarentees that the passed entry remains valid (though
1194 * possibly extended). When merging, this routine may delete one or
1195 * both neighbors. No action is taken on entries which have their
1196 * in-transition flag set.
1198 * The map must be exclusively locked.
1201 vm_map_simplify_entry(vm_map_t map
, vm_map_entry_t entry
, int *countp
)
1203 vm_map_entry_t next
, prev
;
1204 vm_size_t prevsize
, esize
;
1206 if (entry
->eflags
& MAP_ENTRY_IN_TRANSITION
) {
1207 ++mycpu
->gd_cnt
.v_intrans_coll
;
1211 if (entry
->maptype
== VM_MAPTYPE_SUBMAP
)
1215 if (prev
!= &map
->header
) {
1216 prevsize
= prev
->end
- prev
->start
;
1217 if ( (prev
->end
== entry
->start
) &&
1218 (prev
->maptype
== entry
->maptype
) &&
1219 (prev
->object
.vm_object
== entry
->object
.vm_object
) &&
1220 (!prev
->object
.vm_object
||
1221 (prev
->offset
+ prevsize
== entry
->offset
)) &&
1222 (prev
->eflags
== entry
->eflags
) &&
1223 (prev
->protection
== entry
->protection
) &&
1224 (prev
->max_protection
== entry
->max_protection
) &&
1225 (prev
->inheritance
== entry
->inheritance
) &&
1226 (prev
->wired_count
== entry
->wired_count
)) {
1227 if (map
->first_free
== prev
)
1228 map
->first_free
= entry
;
1229 if (map
->hint
== prev
)
1231 vm_map_entry_unlink(map
, prev
);
1232 entry
->start
= prev
->start
;
1233 entry
->offset
= prev
->offset
;
1234 if (prev
->object
.vm_object
)
1235 vm_object_deallocate(prev
->object
.vm_object
);
1236 vm_map_entry_dispose(map
, prev
, countp
);
1241 if (next
!= &map
->header
) {
1242 esize
= entry
->end
- entry
->start
;
1243 if ((entry
->end
== next
->start
) &&
1244 (next
->maptype
== entry
->maptype
) &&
1245 (next
->object
.vm_object
== entry
->object
.vm_object
) &&
1246 (!entry
->object
.vm_object
||
1247 (entry
->offset
+ esize
== next
->offset
)) &&
1248 (next
->eflags
== entry
->eflags
) &&
1249 (next
->protection
== entry
->protection
) &&
1250 (next
->max_protection
== entry
->max_protection
) &&
1251 (next
->inheritance
== entry
->inheritance
) &&
1252 (next
->wired_count
== entry
->wired_count
)) {
1253 if (map
->first_free
== next
)
1254 map
->first_free
= entry
;
1255 if (map
->hint
== next
)
1257 vm_map_entry_unlink(map
, next
);
1258 entry
->end
= next
->end
;
1259 if (next
->object
.vm_object
)
1260 vm_object_deallocate(next
->object
.vm_object
);
1261 vm_map_entry_dispose(map
, next
, countp
);
1267 * Asserts that the given entry begins at or after the specified address.
1268 * If necessary, it splits the entry into two.
1270 #define vm_map_clip_start(map, entry, startaddr, countp) \
1272 if (startaddr > entry->start) \
1273 _vm_map_clip_start(map, entry, startaddr, countp); \
1277 * This routine is called only when it is known that the entry must be split.
1279 * The map must be exclusively locked.
1282 _vm_map_clip_start(vm_map_t map
, vm_map_entry_t entry
, vm_offset_t start
,
1285 vm_map_entry_t new_entry
;
1288 * Split off the front portion -- note that we must insert the new
1289 * entry BEFORE this one, so that this entry has the specified
1293 vm_map_simplify_entry(map
, entry
, countp
);
1296 * If there is no object backing this entry, we might as well create
1297 * one now. If we defer it, an object can get created after the map
1298 * is clipped, and individual objects will be created for the split-up
1299 * map. This is a bit of a hack, but is also about the best place to
1300 * put this improvement.
1302 if (entry
->object
.vm_object
== NULL
&& !map
->system_map
) {
1303 vm_map_entry_allocate_object(entry
);
1306 new_entry
= vm_map_entry_create(map
, countp
);
1307 *new_entry
= *entry
;
1309 new_entry
->end
= start
;
1310 entry
->offset
+= (start
- entry
->start
);
1311 entry
->start
= start
;
1313 vm_map_entry_link(map
, entry
->prev
, new_entry
);
1315 switch(entry
->maptype
) {
1316 case VM_MAPTYPE_NORMAL
:
1317 case VM_MAPTYPE_VPAGETABLE
:
1318 vm_object_reference(new_entry
->object
.vm_object
);
1326 * Asserts that the given entry ends at or before the specified address.
1327 * If necessary, it splits the entry into two.
1329 * The map must be exclusively locked.
1331 #define vm_map_clip_end(map, entry, endaddr, countp) \
1333 if (endaddr < entry->end) \
1334 _vm_map_clip_end(map, entry, endaddr, countp); \
1338 * This routine is called only when it is known that the entry must be split.
1340 * The map must be exclusively locked.
1343 _vm_map_clip_end(vm_map_t map
, vm_map_entry_t entry
, vm_offset_t end
,
1346 vm_map_entry_t new_entry
;
1349 * If there is no object backing this entry, we might as well create
1350 * one now. If we defer it, an object can get created after the map
1351 * is clipped, and individual objects will be created for the split-up
1352 * map. This is a bit of a hack, but is also about the best place to
1353 * put this improvement.
1356 if (entry
->object
.vm_object
== NULL
&& !map
->system_map
) {
1357 vm_map_entry_allocate_object(entry
);
1361 * Create a new entry and insert it AFTER the specified entry
1364 new_entry
= vm_map_entry_create(map
, countp
);
1365 *new_entry
= *entry
;
1367 new_entry
->start
= entry
->end
= end
;
1368 new_entry
->offset
+= (end
- entry
->start
);
1370 vm_map_entry_link(map
, entry
, new_entry
);
1372 switch(entry
->maptype
) {
1373 case VM_MAPTYPE_NORMAL
:
1374 case VM_MAPTYPE_VPAGETABLE
:
1375 vm_object_reference(new_entry
->object
.vm_object
);
1383 * Asserts that the starting and ending region addresses fall within the
1384 * valid range for the map.
1386 #define VM_MAP_RANGE_CHECK(map, start, end) \
1388 if (start < vm_map_min(map)) \
1389 start = vm_map_min(map); \
1390 if (end > vm_map_max(map)) \
1391 end = vm_map_max(map); \
1397 * Used to block when an in-transition collison occurs. The map
1398 * is unlocked for the sleep and relocked before the return.
1402 vm_map_transition_wait(vm_map_t map
)
1405 tsleep(map
, 0, "vment", 0);
1410 * When we do blocking operations with the map lock held it is
1411 * possible that a clip might have occured on our in-transit entry,
1412 * requiring an adjustment to the entry in our loop. These macros
1413 * help the pageable and clip_range code deal with the case. The
1414 * conditional costs virtually nothing if no clipping has occured.
1417 #define CLIP_CHECK_BACK(entry, save_start) \
1419 while (entry->start != save_start) { \
1420 entry = entry->prev; \
1421 KASSERT(entry != &map->header, ("bad entry clip")); \
1425 #define CLIP_CHECK_FWD(entry, save_end) \
1427 while (entry->end != save_end) { \
1428 entry = entry->next; \
1429 KASSERT(entry != &map->header, ("bad entry clip")); \
1435 * Clip the specified range and return the base entry. The
1436 * range may cover several entries starting at the returned base
1437 * and the first and last entry in the covering sequence will be
1438 * properly clipped to the requested start and end address.
1440 * If no holes are allowed you should pass the MAP_CLIP_NO_HOLES
1443 * The MAP_ENTRY_IN_TRANSITION flag will be set for the entries
1444 * covered by the requested range.
1446 * The map must be exclusively locked on entry and will remain locked
1447 * on return. If no range exists or the range contains holes and you
1448 * specified that no holes were allowed, NULL will be returned. This
1449 * routine may temporarily unlock the map in order avoid a deadlock when
1454 vm_map_clip_range(vm_map_t map
, vm_offset_t start
, vm_offset_t end
,
1455 int *countp
, int flags
)
1457 vm_map_entry_t start_entry
;
1458 vm_map_entry_t entry
;
1461 * Locate the entry and effect initial clipping. The in-transition
1462 * case does not occur very often so do not try to optimize it.
1465 if (vm_map_lookup_entry(map
, start
, &start_entry
) == FALSE
)
1467 entry
= start_entry
;
1468 if (entry
->eflags
& MAP_ENTRY_IN_TRANSITION
) {
1469 entry
->eflags
|= MAP_ENTRY_NEEDS_WAKEUP
;
1470 ++mycpu
->gd_cnt
.v_intrans_coll
;
1471 ++mycpu
->gd_cnt
.v_intrans_wait
;
1472 vm_map_transition_wait(map
);
1474 * entry and/or start_entry may have been clipped while
1475 * we slept, or may have gone away entirely. We have
1476 * to restart from the lookup.
1482 * Since we hold an exclusive map lock we do not have to restart
1483 * after clipping, even though clipping may block in zalloc.
1485 vm_map_clip_start(map
, entry
, start
, countp
);
1486 vm_map_clip_end(map
, entry
, end
, countp
);
1487 entry
->eflags
|= MAP_ENTRY_IN_TRANSITION
;
1490 * Scan entries covered by the range. When working on the next
1491 * entry a restart need only re-loop on the current entry which
1492 * we have already locked, since 'next' may have changed. Also,
1493 * even though entry is safe, it may have been clipped so we
1494 * have to iterate forwards through the clip after sleeping.
1496 while (entry
->next
!= &map
->header
&& entry
->next
->start
< end
) {
1497 vm_map_entry_t next
= entry
->next
;
1499 if (flags
& MAP_CLIP_NO_HOLES
) {
1500 if (next
->start
> entry
->end
) {
1501 vm_map_unclip_range(map
, start_entry
,
1502 start
, entry
->end
, countp
, flags
);
1507 if (next
->eflags
& MAP_ENTRY_IN_TRANSITION
) {
1508 vm_offset_t save_end
= entry
->end
;
1509 next
->eflags
|= MAP_ENTRY_NEEDS_WAKEUP
;
1510 ++mycpu
->gd_cnt
.v_intrans_coll
;
1511 ++mycpu
->gd_cnt
.v_intrans_wait
;
1512 vm_map_transition_wait(map
);
1515 * clips might have occured while we blocked.
1517 CLIP_CHECK_FWD(entry
, save_end
);
1518 CLIP_CHECK_BACK(start_entry
, start
);
1522 * No restart necessary even though clip_end may block, we
1523 * are holding the map lock.
1525 vm_map_clip_end(map
, next
, end
, countp
);
1526 next
->eflags
|= MAP_ENTRY_IN_TRANSITION
;
1529 if (flags
& MAP_CLIP_NO_HOLES
) {
1530 if (entry
->end
!= end
) {
1531 vm_map_unclip_range(map
, start_entry
,
1532 start
, entry
->end
, countp
, flags
);
1536 return(start_entry
);
1540 * Undo the effect of vm_map_clip_range(). You should pass the same
1541 * flags and the same range that you passed to vm_map_clip_range().
1542 * This code will clear the in-transition flag on the entries and
1543 * wake up anyone waiting. This code will also simplify the sequence
1544 * and attempt to merge it with entries before and after the sequence.
1546 * The map must be locked on entry and will remain locked on return.
1548 * Note that you should also pass the start_entry returned by
1549 * vm_map_clip_range(). However, if you block between the two calls
1550 * with the map unlocked please be aware that the start_entry may
1551 * have been clipped and you may need to scan it backwards to find
1552 * the entry corresponding with the original start address. You are
1553 * responsible for this, vm_map_unclip_range() expects the correct
1554 * start_entry to be passed to it and will KASSERT otherwise.
1558 vm_map_unclip_range(vm_map_t map
, vm_map_entry_t start_entry
,
1559 vm_offset_t start
, vm_offset_t end
,
1560 int *countp
, int flags
)
1562 vm_map_entry_t entry
;
1564 entry
= start_entry
;
1566 KASSERT(entry
->start
== start
, ("unclip_range: illegal base entry"));
1567 while (entry
!= &map
->header
&& entry
->start
< end
) {
1568 KASSERT(entry
->eflags
& MAP_ENTRY_IN_TRANSITION
,
1569 ("in-transition flag not set during unclip on: %p",
1571 KASSERT(entry
->end
<= end
,
1572 ("unclip_range: tail wasn't clipped"));
1573 entry
->eflags
&= ~MAP_ENTRY_IN_TRANSITION
;
1574 if (entry
->eflags
& MAP_ENTRY_NEEDS_WAKEUP
) {
1575 entry
->eflags
&= ~MAP_ENTRY_NEEDS_WAKEUP
;
1578 entry
= entry
->next
;
1582 * Simplification does not block so there is no restart case.
1584 entry
= start_entry
;
1585 while (entry
!= &map
->header
&& entry
->start
< end
) {
1586 vm_map_simplify_entry(map
, entry
, countp
);
1587 entry
= entry
->next
;
1592 * Mark the given range as handled by a subordinate map.
1594 * This range must have been created with vm_map_find(), and no other
1595 * operations may have been performed on this range prior to calling
1598 * Submappings cannot be removed.
1603 vm_map_submap(vm_map_t map
, vm_offset_t start
, vm_offset_t end
, vm_map_t submap
)
1605 vm_map_entry_t entry
;
1606 int result
= KERN_INVALID_ARGUMENT
;
1609 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
1612 VM_MAP_RANGE_CHECK(map
, start
, end
);
1614 if (vm_map_lookup_entry(map
, start
, &entry
)) {
1615 vm_map_clip_start(map
, entry
, start
, &count
);
1617 entry
= entry
->next
;
1620 vm_map_clip_end(map
, entry
, end
, &count
);
1622 if ((entry
->start
== start
) && (entry
->end
== end
) &&
1623 ((entry
->eflags
& MAP_ENTRY_COW
) == 0) &&
1624 (entry
->object
.vm_object
== NULL
)) {
1625 entry
->object
.sub_map
= submap
;
1626 entry
->maptype
= VM_MAPTYPE_SUBMAP
;
1627 result
= KERN_SUCCESS
;
1630 vm_map_entry_release(count
);
1636 * Sets the protection of the specified address region in the target map.
1637 * If "set_max" is specified, the maximum protection is to be set;
1638 * otherwise, only the current protection is affected.
1640 * The protection is not applicable to submaps, but is applicable to normal
1641 * maps and maps governed by virtual page tables. For example, when operating
1642 * on a virtual page table our protection basically controls how COW occurs
1643 * on the backing object, whereas the virtual page table abstraction itself
1644 * is an abstraction for userland.
1649 vm_map_protect(vm_map_t map
, vm_offset_t start
, vm_offset_t end
,
1650 vm_prot_t new_prot
, boolean_t set_max
)
1652 vm_map_entry_t current
;
1653 vm_map_entry_t entry
;
1656 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
1659 VM_MAP_RANGE_CHECK(map
, start
, end
);
1661 if (vm_map_lookup_entry(map
, start
, &entry
)) {
1662 vm_map_clip_start(map
, entry
, start
, &count
);
1664 entry
= entry
->next
;
1668 * Make a first pass to check for protection violations.
1671 while ((current
!= &map
->header
) && (current
->start
< end
)) {
1672 if (current
->maptype
== VM_MAPTYPE_SUBMAP
) {
1674 vm_map_entry_release(count
);
1675 return (KERN_INVALID_ARGUMENT
);
1677 if ((new_prot
& current
->max_protection
) != new_prot
) {
1679 vm_map_entry_release(count
);
1680 return (KERN_PROTECTION_FAILURE
);
1682 current
= current
->next
;
1686 * Go back and fix up protections. [Note that clipping is not
1687 * necessary the second time.]
1691 while ((current
!= &map
->header
) && (current
->start
< end
)) {
1694 vm_map_clip_end(map
, current
, end
, &count
);
1696 old_prot
= current
->protection
;
1698 current
->protection
=
1699 (current
->max_protection
= new_prot
) &
1702 current
->protection
= new_prot
;
1706 * Update physical map if necessary. Worry about copy-on-write
1707 * here -- CHECK THIS XXX
1710 if (current
->protection
!= old_prot
) {
1711 #define MASK(entry) (((entry)->eflags & MAP_ENTRY_COW) ? ~VM_PROT_WRITE : \
1714 pmap_protect(map
->pmap
, current
->start
,
1716 current
->protection
& MASK(current
));
1720 vm_map_simplify_entry(map
, current
, &count
);
1722 current
= current
->next
;
1726 vm_map_entry_release(count
);
1727 return (KERN_SUCCESS
);
1731 * This routine traverses a processes map handling the madvise
1732 * system call. Advisories are classified as either those effecting
1733 * the vm_map_entry structure, or those effecting the underlying
1736 * The <value> argument is used for extended madvise calls.
1741 vm_map_madvise(vm_map_t map
, vm_offset_t start
, vm_offset_t end
,
1742 int behav
, off_t value
)
1744 vm_map_entry_t current
, entry
;
1750 * Some madvise calls directly modify the vm_map_entry, in which case
1751 * we need to use an exclusive lock on the map and we need to perform
1752 * various clipping operations. Otherwise we only need a read-lock
1756 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
1760 case MADV_SEQUENTIAL
:
1774 vm_map_lock_read(map
);
1777 vm_map_entry_release(count
);
1782 * Locate starting entry and clip if necessary.
1785 VM_MAP_RANGE_CHECK(map
, start
, end
);
1787 if (vm_map_lookup_entry(map
, start
, &entry
)) {
1789 vm_map_clip_start(map
, entry
, start
, &count
);
1791 entry
= entry
->next
;
1796 * madvise behaviors that are implemented in the vm_map_entry.
1798 * We clip the vm_map_entry so that behavioral changes are
1799 * limited to the specified address range.
1801 for (current
= entry
;
1802 (current
!= &map
->header
) && (current
->start
< end
);
1803 current
= current
->next
1805 if (current
->maptype
== VM_MAPTYPE_SUBMAP
)
1808 vm_map_clip_end(map
, current
, end
, &count
);
1812 vm_map_entry_set_behavior(current
, MAP_ENTRY_BEHAV_NORMAL
);
1814 case MADV_SEQUENTIAL
:
1815 vm_map_entry_set_behavior(current
, MAP_ENTRY_BEHAV_SEQUENTIAL
);
1818 vm_map_entry_set_behavior(current
, MAP_ENTRY_BEHAV_RANDOM
);
1821 current
->eflags
|= MAP_ENTRY_NOSYNC
;
1824 current
->eflags
&= ~MAP_ENTRY_NOSYNC
;
1827 current
->eflags
|= MAP_ENTRY_NOCOREDUMP
;
1830 current
->eflags
&= ~MAP_ENTRY_NOCOREDUMP
;
1834 * Invalidate the related pmap entries, used
1835 * to flush portions of the real kernel's
1836 * pmap when the caller has removed or
1837 * modified existing mappings in a virtual
1840 pmap_remove(map
->pmap
,
1841 current
->start
, current
->end
);
1845 * Set the page directory page for a map
1846 * governed by a virtual page table. Mark
1847 * the entry as being governed by a virtual
1848 * page table if it is not.
1850 * XXX the page directory page is stored
1851 * in the avail_ssize field if the map_entry.
1853 * XXX the map simplification code does not
1854 * compare this field so weird things may
1855 * happen if you do not apply this function
1856 * to the entire mapping governed by the
1857 * virtual page table.
1859 if (current
->maptype
!= VM_MAPTYPE_VPAGETABLE
) {
1863 current
->aux
.master_pde
= value
;
1864 pmap_remove(map
->pmap
,
1865 current
->start
, current
->end
);
1871 vm_map_simplify_entry(map
, current
, &count
);
1879 * madvise behaviors that are implemented in the underlying
1882 * Since we don't clip the vm_map_entry, we have to clip
1883 * the vm_object pindex and count.
1885 * NOTE! We currently do not support these functions on
1886 * virtual page tables.
1888 for (current
= entry
;
1889 (current
!= &map
->header
) && (current
->start
< end
);
1890 current
= current
->next
1892 vm_offset_t useStart
;
1894 if (current
->maptype
!= VM_MAPTYPE_NORMAL
)
1897 pindex
= OFF_TO_IDX(current
->offset
);
1898 count
= atop(current
->end
- current
->start
);
1899 useStart
= current
->start
;
1901 if (current
->start
< start
) {
1902 pindex
+= atop(start
- current
->start
);
1903 count
-= atop(start
- current
->start
);
1906 if (current
->end
> end
)
1907 count
-= atop(current
->end
- end
);
1912 vm_object_madvise(current
->object
.vm_object
,
1913 pindex
, count
, behav
);
1916 * Try to populate the page table. Mappings governed
1917 * by virtual page tables cannot be pre-populated
1918 * without a lot of work so don't try.
1920 if (behav
== MADV_WILLNEED
&&
1921 current
->maptype
!= VM_MAPTYPE_VPAGETABLE
) {
1922 pmap_object_init_pt(
1925 current
->protection
,
1926 current
->object
.vm_object
,
1928 (count
<< PAGE_SHIFT
),
1929 MAP_PREFAULT_MADVISE
1933 vm_map_unlock_read(map
);
1935 vm_map_entry_release(count
);
1941 * Sets the inheritance of the specified address range in the target map.
1942 * Inheritance affects how the map will be shared with child maps at the
1943 * time of vm_map_fork.
1946 vm_map_inherit(vm_map_t map
, vm_offset_t start
, vm_offset_t end
,
1947 vm_inherit_t new_inheritance
)
1949 vm_map_entry_t entry
;
1950 vm_map_entry_t temp_entry
;
1953 switch (new_inheritance
) {
1954 case VM_INHERIT_NONE
:
1955 case VM_INHERIT_COPY
:
1956 case VM_INHERIT_SHARE
:
1959 return (KERN_INVALID_ARGUMENT
);
1962 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
1965 VM_MAP_RANGE_CHECK(map
, start
, end
);
1967 if (vm_map_lookup_entry(map
, start
, &temp_entry
)) {
1969 vm_map_clip_start(map
, entry
, start
, &count
);
1971 entry
= temp_entry
->next
;
1973 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
1974 vm_map_clip_end(map
, entry
, end
, &count
);
1976 entry
->inheritance
= new_inheritance
;
1978 vm_map_simplify_entry(map
, entry
, &count
);
1980 entry
= entry
->next
;
1983 vm_map_entry_release(count
);
1984 return (KERN_SUCCESS
);
1988 * Implement the semantics of mlock
1991 vm_map_unwire(vm_map_t map
, vm_offset_t start
, vm_offset_t real_end
,
1992 boolean_t new_pageable
)
1994 vm_map_entry_t entry
;
1995 vm_map_entry_t start_entry
;
1997 int rv
= KERN_SUCCESS
;
2000 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
2002 VM_MAP_RANGE_CHECK(map
, start
, real_end
);
2005 start_entry
= vm_map_clip_range(map
, start
, end
, &count
,
2007 if (start_entry
== NULL
) {
2009 vm_map_entry_release(count
);
2010 return (KERN_INVALID_ADDRESS
);
2013 if (new_pageable
== 0) {
2014 entry
= start_entry
;
2015 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
2016 vm_offset_t save_start
;
2017 vm_offset_t save_end
;
2020 * Already user wired or hard wired (trivial cases)
2022 if (entry
->eflags
& MAP_ENTRY_USER_WIRED
) {
2023 entry
= entry
->next
;
2026 if (entry
->wired_count
!= 0) {
2027 entry
->wired_count
++;
2028 entry
->eflags
|= MAP_ENTRY_USER_WIRED
;
2029 entry
= entry
->next
;
2034 * A new wiring requires instantiation of appropriate
2035 * management structures and the faulting in of the
2038 if (entry
->maptype
!= VM_MAPTYPE_SUBMAP
) {
2039 int copyflag
= entry
->eflags
&
2040 MAP_ENTRY_NEEDS_COPY
;
2041 if (copyflag
&& ((entry
->protection
&
2042 VM_PROT_WRITE
) != 0)) {
2043 vm_map_entry_shadow(entry
);
2044 } else if (entry
->object
.vm_object
== NULL
&&
2046 vm_map_entry_allocate_object(entry
);
2049 entry
->wired_count
++;
2050 entry
->eflags
|= MAP_ENTRY_USER_WIRED
;
2053 * Now fault in the area. Note that vm_fault_wire()
2054 * may release the map lock temporarily, it will be
2055 * relocked on return. The in-transition
2056 * flag protects the entries.
2058 save_start
= entry
->start
;
2059 save_end
= entry
->end
;
2060 rv
= vm_fault_wire(map
, entry
, TRUE
);
2062 CLIP_CHECK_BACK(entry
, save_start
);
2064 KASSERT(entry
->wired_count
== 1, ("bad wired_count on entry"));
2065 entry
->eflags
&= ~MAP_ENTRY_USER_WIRED
;
2066 entry
->wired_count
= 0;
2067 if (entry
->end
== save_end
)
2069 entry
= entry
->next
;
2070 KASSERT(entry
!= &map
->header
, ("bad entry clip during backout"));
2072 end
= save_start
; /* unwire the rest */
2076 * note that even though the entry might have been
2077 * clipped, the USER_WIRED flag we set prevents
2078 * duplication so we do not have to do a
2081 entry
= entry
->next
;
2085 * If we failed fall through to the unwiring section to
2086 * unwire what we had wired so far. 'end' has already
2093 * start_entry might have been clipped if we unlocked the
2094 * map and blocked. No matter how clipped it has gotten
2095 * there should be a fragment that is on our start boundary.
2097 CLIP_CHECK_BACK(start_entry
, start
);
2101 * Deal with the unwiring case.
2105 * This is the unwiring case. We must first ensure that the
2106 * range to be unwired is really wired down. We know there
2109 entry
= start_entry
;
2110 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
2111 if ((entry
->eflags
& MAP_ENTRY_USER_WIRED
) == 0) {
2112 rv
= KERN_INVALID_ARGUMENT
;
2115 KASSERT(entry
->wired_count
!= 0, ("wired count was 0 with USER_WIRED set! %p", entry
));
2116 entry
= entry
->next
;
2120 * Now decrement the wiring count for each region. If a region
2121 * becomes completely unwired, unwire its physical pages and
2125 * The map entries are processed in a loop, checking to
2126 * make sure the entry is wired and asserting it has a wired
2127 * count. However, another loop was inserted more-or-less in
2128 * the middle of the unwiring path. This loop picks up the
2129 * "entry" loop variable from the first loop without first
2130 * setting it to start_entry. Naturally, the secound loop
2131 * is never entered and the pages backing the entries are
2132 * never unwired. This can lead to a leak of wired pages.
2134 entry
= start_entry
;
2135 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
2136 KASSERT(entry
->eflags
& MAP_ENTRY_USER_WIRED
,
2137 ("expected USER_WIRED on entry %p", entry
));
2138 entry
->eflags
&= ~MAP_ENTRY_USER_WIRED
;
2139 entry
->wired_count
--;
2140 if (entry
->wired_count
== 0)
2141 vm_fault_unwire(map
, entry
);
2142 entry
= entry
->next
;
2146 vm_map_unclip_range(map
, start_entry
, start
, real_end
, &count
,
2150 vm_map_entry_release(count
);
2155 * Sets the pageability of the specified address range in the target map.
2156 * Regions specified as not pageable require locked-down physical
2157 * memory and physical page maps.
2159 * The map must not be locked, but a reference must remain to the map
2160 * throughout the call.
2162 * This function may be called via the zalloc path and must properly
2163 * reserve map entries for kernel_map.
2168 vm_map_wire(vm_map_t map
, vm_offset_t start
, vm_offset_t real_end
, int kmflags
)
2170 vm_map_entry_t entry
;
2171 vm_map_entry_t start_entry
;
2173 int rv
= KERN_SUCCESS
;
2176 if (kmflags
& KM_KRESERVE
)
2177 count
= vm_map_entry_kreserve(MAP_RESERVE_COUNT
);
2179 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
2181 VM_MAP_RANGE_CHECK(map
, start
, real_end
);
2184 start_entry
= vm_map_clip_range(map
, start
, end
, &count
,
2186 if (start_entry
== NULL
) {
2188 rv
= KERN_INVALID_ADDRESS
;
2191 if ((kmflags
& KM_PAGEABLE
) == 0) {
2195 * 1. Holding the write lock, we create any shadow or zero-fill
2196 * objects that need to be created. Then we clip each map
2197 * entry to the region to be wired and increment its wiring
2198 * count. We create objects before clipping the map entries
2199 * to avoid object proliferation.
2201 * 2. We downgrade to a read lock, and call vm_fault_wire to
2202 * fault in the pages for any newly wired area (wired_count is
2205 * Downgrading to a read lock for vm_fault_wire avoids a
2206 * possible deadlock with another process that may have faulted
2207 * on one of the pages to be wired (it would mark the page busy,
2208 * blocking us, then in turn block on the map lock that we
2209 * hold). Because of problems in the recursive lock package,
2210 * we cannot upgrade to a write lock in vm_map_lookup. Thus,
2211 * any actions that require the write lock must be done
2212 * beforehand. Because we keep the read lock on the map, the
2213 * copy-on-write status of the entries we modify here cannot
2216 entry
= start_entry
;
2217 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
2219 * Trivial case if the entry is already wired
2221 if (entry
->wired_count
) {
2222 entry
->wired_count
++;
2223 entry
= entry
->next
;
2228 * The entry is being newly wired, we have to setup
2229 * appropriate management structures. A shadow
2230 * object is required for a copy-on-write region,
2231 * or a normal object for a zero-fill region. We
2232 * do not have to do this for entries that point to sub
2233 * maps because we won't hold the lock on the sub map.
2235 if (entry
->maptype
!= VM_MAPTYPE_SUBMAP
) {
2236 int copyflag
= entry
->eflags
&
2237 MAP_ENTRY_NEEDS_COPY
;
2238 if (copyflag
&& ((entry
->protection
&
2239 VM_PROT_WRITE
) != 0)) {
2240 vm_map_entry_shadow(entry
);
2241 } else if (entry
->object
.vm_object
== NULL
&&
2243 vm_map_entry_allocate_object(entry
);
2247 entry
->wired_count
++;
2248 entry
= entry
->next
;
2256 * HACK HACK HACK HACK
2258 * vm_fault_wire() temporarily unlocks the map to avoid
2259 * deadlocks. The in-transition flag from vm_map_clip_range
2260 * call should protect us from changes while the map is
2263 * NOTE: Previously this comment stated that clipping might
2264 * still occur while the entry is unlocked, but from
2265 * what I can tell it actually cannot.
2267 * It is unclear whether the CLIP_CHECK_*() calls
2268 * are still needed but we keep them in anyway.
2270 * HACK HACK HACK HACK
2273 entry
= start_entry
;
2274 while (entry
!= &map
->header
&& entry
->start
< end
) {
2276 * If vm_fault_wire fails for any page we need to undo
2277 * what has been done. We decrement the wiring count
2278 * for those pages which have not yet been wired (now)
2279 * and unwire those that have (later).
2281 vm_offset_t save_start
= entry
->start
;
2282 vm_offset_t save_end
= entry
->end
;
2284 if (entry
->wired_count
== 1)
2285 rv
= vm_fault_wire(map
, entry
, FALSE
);
2287 CLIP_CHECK_BACK(entry
, save_start
);
2289 KASSERT(entry
->wired_count
== 1, ("wired_count changed unexpectedly"));
2290 entry
->wired_count
= 0;
2291 if (entry
->end
== save_end
)
2293 entry
= entry
->next
;
2294 KASSERT(entry
!= &map
->header
, ("bad entry clip during backout"));
2299 CLIP_CHECK_FWD(entry
, save_end
);
2300 entry
= entry
->next
;
2304 * If a failure occured undo everything by falling through
2305 * to the unwiring code. 'end' has already been adjusted
2309 kmflags
|= KM_PAGEABLE
;
2312 * start_entry is still IN_TRANSITION but may have been
2313 * clipped since vm_fault_wire() unlocks and relocks the
2314 * map. No matter how clipped it has gotten there should
2315 * be a fragment that is on our start boundary.
2317 CLIP_CHECK_BACK(start_entry
, start
);
2320 if (kmflags
& KM_PAGEABLE
) {
2322 * This is the unwiring case. We must first ensure that the
2323 * range to be unwired is really wired down. We know there
2326 entry
= start_entry
;
2327 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
2328 if (entry
->wired_count
== 0) {
2329 rv
= KERN_INVALID_ARGUMENT
;
2332 entry
= entry
->next
;
2336 * Now decrement the wiring count for each region. If a region
2337 * becomes completely unwired, unwire its physical pages and
2340 entry
= start_entry
;
2341 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
2342 entry
->wired_count
--;
2343 if (entry
->wired_count
== 0)
2344 vm_fault_unwire(map
, entry
);
2345 entry
= entry
->next
;
2349 vm_map_unclip_range(map
, start_entry
, start
, real_end
,
2350 &count
, MAP_CLIP_NO_HOLES
);
2354 if (kmflags
& KM_KRESERVE
)
2355 vm_map_entry_krelease(count
);
2357 vm_map_entry_release(count
);
2362 * Mark a newly allocated address range as wired but do not fault in
2363 * the pages. The caller is expected to load the pages into the object.
2365 * The map must be locked on entry and will remain locked on return.
2366 * No other requirements.
2369 vm_map_set_wired_quick(vm_map_t map
, vm_offset_t addr
, vm_size_t size
,
2372 vm_map_entry_t scan
;
2373 vm_map_entry_t entry
;
2375 entry
= vm_map_clip_range(map
, addr
, addr
+ size
,
2376 countp
, MAP_CLIP_NO_HOLES
);
2378 scan
!= &map
->header
&& scan
->start
< addr
+ size
;
2379 scan
= scan
->next
) {
2380 KKASSERT(entry
->wired_count
== 0);
2381 entry
->wired_count
= 1;
2383 vm_map_unclip_range(map
, entry
, addr
, addr
+ size
,
2384 countp
, MAP_CLIP_NO_HOLES
);
2388 * Push any dirty cached pages in the address range to their pager.
2389 * If syncio is TRUE, dirty pages are written synchronously.
2390 * If invalidate is TRUE, any cached pages are freed as well.
2392 * This routine is called by sys_msync()
2394 * Returns an error if any part of the specified range is not mapped.
2399 vm_map_clean(vm_map_t map
, vm_offset_t start
, vm_offset_t end
,
2400 boolean_t syncio
, boolean_t invalidate
)
2402 vm_map_entry_t current
;
2403 vm_map_entry_t entry
;
2406 vm_ooffset_t offset
;
2408 vm_map_lock_read(map
);
2409 VM_MAP_RANGE_CHECK(map
, start
, end
);
2410 if (!vm_map_lookup_entry(map
, start
, &entry
)) {
2411 vm_map_unlock_read(map
);
2412 return (KERN_INVALID_ADDRESS
);
2415 * Make a first pass to check for holes.
2417 for (current
= entry
; current
->start
< end
; current
= current
->next
) {
2418 if (current
->maptype
== VM_MAPTYPE_SUBMAP
) {
2419 vm_map_unlock_read(map
);
2420 return (KERN_INVALID_ARGUMENT
);
2422 if (end
> current
->end
&&
2423 (current
->next
== &map
->header
||
2424 current
->end
!= current
->next
->start
)) {
2425 vm_map_unlock_read(map
);
2426 return (KERN_INVALID_ADDRESS
);
2431 pmap_remove(vm_map_pmap(map
), start
, end
);
2434 * Make a second pass, cleaning/uncaching pages from the indicated
2437 * Hold vm_token to avoid blocking in vm_object_reference()
2439 lwkt_gettoken(&vm_token
);
2440 for (current
= entry
; current
->start
< end
; current
= current
->next
) {
2441 offset
= current
->offset
+ (start
- current
->start
);
2442 size
= (end
<= current
->end
? end
: current
->end
) - start
;
2443 if (current
->maptype
== VM_MAPTYPE_SUBMAP
) {
2445 vm_map_entry_t tentry
;
2448 smap
= current
->object
.sub_map
;
2449 vm_map_lock_read(smap
);
2450 vm_map_lookup_entry(smap
, offset
, &tentry
);
2451 tsize
= tentry
->end
- offset
;
2454 object
= tentry
->object
.vm_object
;
2455 offset
= tentry
->offset
+ (offset
- tentry
->start
);
2456 vm_map_unlock_read(smap
);
2458 object
= current
->object
.vm_object
;
2461 * Note that there is absolutely no sense in writing out
2462 * anonymous objects, so we track down the vnode object
2464 * We invalidate (remove) all pages from the address space
2465 * anyway, for semantic correctness.
2467 * note: certain anonymous maps, such as MAP_NOSYNC maps,
2468 * may start out with a NULL object.
2470 while (object
&& object
->backing_object
) {
2471 offset
+= object
->backing_object_offset
;
2472 object
= object
->backing_object
;
2473 if (object
->size
< OFF_TO_IDX( offset
+ size
))
2474 size
= IDX_TO_OFF(object
->size
) - offset
;
2476 if (object
&& (object
->type
== OBJT_VNODE
) &&
2477 (current
->protection
& VM_PROT_WRITE
) &&
2478 (object
->flags
& OBJ_NOMSYNC
) == 0) {
2480 * Flush pages if writing is allowed, invalidate them
2481 * if invalidation requested. Pages undergoing I/O
2482 * will be ignored by vm_object_page_remove().
2484 * We cannot lock the vnode and then wait for paging
2485 * to complete without deadlocking against vm_fault.
2486 * Instead we simply call vm_object_page_remove() and
2487 * allow it to block internally on a page-by-page
2488 * basis when it encounters pages undergoing async
2493 vm_object_reference(object
);
2494 vn_lock(object
->handle
, LK_EXCLUSIVE
| LK_RETRY
);
2495 flags
= (syncio
|| invalidate
) ? OBJPC_SYNC
: 0;
2496 flags
|= invalidate
? OBJPC_INVAL
: 0;
2499 * When operating on a virtual page table just
2500 * flush the whole object. XXX we probably ought
2503 switch(current
->maptype
) {
2504 case VM_MAPTYPE_NORMAL
:
2505 vm_object_page_clean(object
,
2507 OFF_TO_IDX(offset
+ size
+ PAGE_MASK
),
2510 case VM_MAPTYPE_VPAGETABLE
:
2511 vm_object_page_clean(object
, 0, 0, flags
);
2514 vn_unlock(((struct vnode
*)object
->handle
));
2515 vm_object_deallocate(object
);
2517 if (object
&& invalidate
&&
2518 ((object
->type
== OBJT_VNODE
) ||
2519 (object
->type
== OBJT_DEVICE
))) {
2521 (object
->type
== OBJT_DEVICE
) ? FALSE
: TRUE
;
2522 vm_object_reference(object
);
2523 switch(current
->maptype
) {
2524 case VM_MAPTYPE_NORMAL
:
2525 vm_object_page_remove(object
,
2527 OFF_TO_IDX(offset
+ size
+ PAGE_MASK
),
2530 case VM_MAPTYPE_VPAGETABLE
:
2531 vm_object_page_remove(object
, 0, 0, clean_only
);
2534 vm_object_deallocate(object
);
2538 vm_map_unlock_read(map
);
2539 lwkt_reltoken(&vm_token
);
2541 return (KERN_SUCCESS
);
2545 * Make the region specified by this entry pageable.
2547 * The vm_map must be exclusively locked.
2550 vm_map_entry_unwire(vm_map_t map
, vm_map_entry_t entry
)
2552 entry
->eflags
&= ~MAP_ENTRY_USER_WIRED
;
2553 entry
->wired_count
= 0;
2554 vm_fault_unwire(map
, entry
);
2558 * Deallocate the given entry from the target map.
2560 * The vm_map must be exclusively locked.
2563 vm_map_entry_delete(vm_map_t map
, vm_map_entry_t entry
, int *countp
)
2565 vm_map_entry_unlink(map
, entry
);
2566 map
->size
-= entry
->end
- entry
->start
;
2568 switch(entry
->maptype
) {
2569 case VM_MAPTYPE_NORMAL
:
2570 case VM_MAPTYPE_VPAGETABLE
:
2571 vm_object_deallocate(entry
->object
.vm_object
);
2577 vm_map_entry_dispose(map
, entry
, countp
);
2581 * Deallocates the given address range from the target map.
2583 * The vm_map must be exclusively locked.
2586 vm_map_delete(vm_map_t map
, vm_offset_t start
, vm_offset_t end
, int *countp
)
2589 vm_map_entry_t entry
;
2590 vm_map_entry_t first_entry
;
2592 ASSERT_VM_MAP_LOCKED(map
);
2595 * Find the start of the region, and clip it. Set entry to point
2596 * at the first record containing the requested address or, if no
2597 * such record exists, the next record with a greater address. The
2598 * loop will run from this point until a record beyond the termination
2599 * address is encountered.
2601 * map->hint must be adjusted to not point to anything we delete,
2602 * so set it to the entry prior to the one being deleted.
2604 * GGG see other GGG comment.
2606 if (vm_map_lookup_entry(map
, start
, &first_entry
)) {
2607 entry
= first_entry
;
2608 vm_map_clip_start(map
, entry
, start
, countp
);
2609 map
->hint
= entry
->prev
; /* possible problem XXX */
2611 map
->hint
= first_entry
; /* possible problem XXX */
2612 entry
= first_entry
->next
;
2616 * If a hole opens up prior to the current first_free then
2617 * adjust first_free. As with map->hint, map->first_free
2618 * cannot be left set to anything we might delete.
2620 if (entry
== &map
->header
) {
2621 map
->first_free
= &map
->header
;
2622 } else if (map
->first_free
->start
>= start
) {
2623 map
->first_free
= entry
->prev
;
2627 * Step through all entries in this region
2629 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
2630 vm_map_entry_t next
;
2632 vm_pindex_t offidxstart
, offidxend
, count
;
2635 * If we hit an in-transition entry we have to sleep and
2636 * retry. It's easier (and not really slower) to just retry
2637 * since this case occurs so rarely and the hint is already
2638 * pointing at the right place. We have to reset the
2639 * start offset so as not to accidently delete an entry
2640 * another process just created in vacated space.
2642 if (entry
->eflags
& MAP_ENTRY_IN_TRANSITION
) {
2643 entry
->eflags
|= MAP_ENTRY_NEEDS_WAKEUP
;
2644 start
= entry
->start
;
2645 ++mycpu
->gd_cnt
.v_intrans_coll
;
2646 ++mycpu
->gd_cnt
.v_intrans_wait
;
2647 vm_map_transition_wait(map
);
2650 vm_map_clip_end(map
, entry
, end
, countp
);
2656 offidxstart
= OFF_TO_IDX(entry
->offset
);
2657 count
= OFF_TO_IDX(e
- s
);
2658 object
= entry
->object
.vm_object
;
2661 * Unwire before removing addresses from the pmap; otherwise,
2662 * unwiring will put the entries back in the pmap.
2664 if (entry
->wired_count
!= 0)
2665 vm_map_entry_unwire(map
, entry
);
2667 offidxend
= offidxstart
+ count
;
2670 * Hold vm_token when manipulating vm_objects.
2672 lwkt_gettoken(&vm_token
);
2673 if (object
== &kernel_object
) {
2674 vm_object_page_remove(object
, offidxstart
,
2677 pmap_remove(map
->pmap
, s
, e
);
2678 if (object
!= NULL
&&
2679 object
->ref_count
!= 1 &&
2680 (object
->flags
& (OBJ_NOSPLIT
|OBJ_ONEMAPPING
)) ==
2682 (object
->type
== OBJT_DEFAULT
||
2683 object
->type
== OBJT_SWAP
)) {
2684 vm_object_collapse(object
);
2685 vm_object_page_remove(object
, offidxstart
,
2687 if (object
->type
== OBJT_SWAP
) {
2688 swap_pager_freespace(object
,
2692 if (offidxend
>= object
->size
&&
2693 offidxstart
< object
->size
) {
2694 object
->size
= offidxstart
;
2698 lwkt_reltoken(&vm_token
);
2701 * Delete the entry (which may delete the object) only after
2702 * removing all pmap entries pointing to its pages.
2703 * (Otherwise, its page frames may be reallocated, and any
2704 * modify bits will be set in the wrong object!)
2706 vm_map_entry_delete(map
, entry
, countp
);
2709 return (KERN_SUCCESS
);
2713 * Remove the given address range from the target map.
2714 * This is the exported form of vm_map_delete.
2719 vm_map_remove(vm_map_t map
, vm_offset_t start
, vm_offset_t end
)
2724 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
2726 VM_MAP_RANGE_CHECK(map
, start
, end
);
2727 result
= vm_map_delete(map
, start
, end
, &count
);
2729 vm_map_entry_release(count
);
2735 * Assert that the target map allows the specified privilege on the
2736 * entire address region given. The entire region must be allocated.
2738 * The caller must specify whether the vm_map is already locked or not.
2741 vm_map_check_protection(vm_map_t map
, vm_offset_t start
, vm_offset_t end
,
2742 vm_prot_t protection
, boolean_t have_lock
)
2744 vm_map_entry_t entry
;
2745 vm_map_entry_t tmp_entry
;
2748 if (have_lock
== FALSE
)
2749 vm_map_lock_read(map
);
2751 if (!vm_map_lookup_entry(map
, start
, &tmp_entry
)) {
2752 if (have_lock
== FALSE
)
2753 vm_map_unlock_read(map
);
2759 while (start
< end
) {
2760 if (entry
== &map
->header
) {
2768 if (start
< entry
->start
) {
2773 * Check protection associated with entry.
2776 if ((entry
->protection
& protection
) != protection
) {
2780 /* go to next entry */
2783 entry
= entry
->next
;
2785 if (have_lock
== FALSE
)
2786 vm_map_unlock_read(map
);
2791 * Split the pages in a map entry into a new object. This affords
2792 * easier removal of unused pages, and keeps object inheritance from
2793 * being a negative impact on memory usage.
2795 * The vm_map must be exclusively locked.
2798 vm_map_split(vm_map_entry_t entry
)
2801 vm_object_t orig_object
, new_object
, source
;
2803 vm_pindex_t offidxstart
, offidxend
, idx
;
2805 vm_ooffset_t offset
;
2807 orig_object
= entry
->object
.vm_object
;
2808 if (orig_object
->type
!= OBJT_DEFAULT
&& orig_object
->type
!= OBJT_SWAP
)
2810 if (orig_object
->ref_count
<= 1)
2813 offset
= entry
->offset
;
2817 offidxstart
= OFF_TO_IDX(offset
);
2818 offidxend
= offidxstart
+ OFF_TO_IDX(e
- s
);
2819 size
= offidxend
- offidxstart
;
2821 switch(orig_object
->type
) {
2823 new_object
= default_pager_alloc(NULL
, IDX_TO_OFF(size
),
2827 new_object
= swap_pager_alloc(NULL
, IDX_TO_OFF(size
),
2835 if (new_object
== NULL
)
2839 * vm_token required when manipulating vm_objects.
2841 lwkt_gettoken(&vm_token
);
2843 source
= orig_object
->backing_object
;
2844 if (source
!= NULL
) {
2845 vm_object_reference(source
); /* Referenced by new_object */
2846 LIST_INSERT_HEAD(&source
->shadow_head
,
2847 new_object
, shadow_list
);
2848 vm_object_clear_flag(source
, OBJ_ONEMAPPING
);
2849 new_object
->backing_object_offset
=
2850 orig_object
->backing_object_offset
+ IDX_TO_OFF(offidxstart
);
2851 new_object
->backing_object
= source
;
2852 source
->shadow_count
++;
2853 source
->generation
++;
2856 for (idx
= 0; idx
< size
; idx
++) {
2861 m
= vm_page_lookup(orig_object
, offidxstart
+ idx
);
2868 * We must wait for pending I/O to complete before we can
2871 * We do not have to VM_PROT_NONE the page as mappings should
2872 * not be changed by this operation.
2874 if (vm_page_sleep_busy(m
, TRUE
, "spltwt"))
2877 vm_page_rename(m
, new_object
, idx
);
2878 /* page automatically made dirty by rename and cache handled */
2883 if (orig_object
->type
== OBJT_SWAP
) {
2884 vm_object_pip_add(orig_object
, 1);
2886 * copy orig_object pages into new_object
2887 * and destroy unneeded pages in
2890 swap_pager_copy(orig_object
, new_object
, offidxstart
, 0);
2891 vm_object_pip_wakeup(orig_object
);
2895 * Wakeup the pages we played with. No spl protection is needed
2896 * for a simple wakeup.
2898 for (idx
= 0; idx
< size
; idx
++) {
2899 m
= vm_page_lookup(new_object
, idx
);
2904 entry
->object
.vm_object
= new_object
;
2905 entry
->offset
= 0LL;
2906 vm_object_deallocate(orig_object
);
2907 lwkt_reltoken(&vm_token
);
2911 * Copies the contents of the source entry to the destination
2912 * entry. The entries *must* be aligned properly.
2914 * The vm_map must be exclusively locked.
2917 vm_map_copy_entry(vm_map_t src_map
, vm_map_t dst_map
,
2918 vm_map_entry_t src_entry
, vm_map_entry_t dst_entry
)
2920 vm_object_t src_object
;
2922 if (dst_entry
->maptype
== VM_MAPTYPE_SUBMAP
)
2924 if (src_entry
->maptype
== VM_MAPTYPE_SUBMAP
)
2927 lwkt_gettoken(&vm_token
);
2928 if (src_entry
->wired_count
== 0) {
2930 * If the source entry is marked needs_copy, it is already
2933 if ((src_entry
->eflags
& MAP_ENTRY_NEEDS_COPY
) == 0) {
2934 pmap_protect(src_map
->pmap
,
2937 src_entry
->protection
& ~VM_PROT_WRITE
);
2941 * Make a copy of the object.
2943 if ((src_object
= src_entry
->object
.vm_object
) != NULL
) {
2944 if ((src_object
->handle
== NULL
) &&
2945 (src_object
->type
== OBJT_DEFAULT
||
2946 src_object
->type
== OBJT_SWAP
)) {
2947 vm_object_collapse(src_object
);
2948 if ((src_object
->flags
& (OBJ_NOSPLIT
|OBJ_ONEMAPPING
)) == OBJ_ONEMAPPING
) {
2949 vm_map_split(src_entry
);
2950 src_object
= src_entry
->object
.vm_object
;
2954 vm_object_reference(src_object
);
2955 vm_object_clear_flag(src_object
, OBJ_ONEMAPPING
);
2956 dst_entry
->object
.vm_object
= src_object
;
2957 src_entry
->eflags
|= (MAP_ENTRY_COW
|MAP_ENTRY_NEEDS_COPY
);
2958 dst_entry
->eflags
|= (MAP_ENTRY_COW
|MAP_ENTRY_NEEDS_COPY
);
2959 dst_entry
->offset
= src_entry
->offset
;
2961 dst_entry
->object
.vm_object
= NULL
;
2962 dst_entry
->offset
= 0;
2965 pmap_copy(dst_map
->pmap
, src_map
->pmap
, dst_entry
->start
,
2966 dst_entry
->end
- dst_entry
->start
, src_entry
->start
);
2969 * Of course, wired down pages can't be set copy-on-write.
2970 * Cause wired pages to be copied into the new map by
2971 * simulating faults (the new pages are pageable)
2973 vm_fault_copy_entry(dst_map
, src_map
, dst_entry
, src_entry
);
2975 lwkt_reltoken(&vm_token
);
2980 * Create a new process vmspace structure and vm_map
2981 * based on those of an existing process. The new map
2982 * is based on the old map, according to the inheritance
2983 * values on the regions in that map.
2985 * The source map must not be locked.
2989 vmspace_fork(struct vmspace
*vm1
)
2991 struct vmspace
*vm2
;
2992 vm_map_t old_map
= &vm1
->vm_map
;
2994 vm_map_entry_t old_entry
;
2995 vm_map_entry_t new_entry
;
2999 lwkt_gettoken(&vm_token
);
3000 lwkt_gettoken(&vmspace_token
);
3001 vm_map_lock(old_map
);
3002 old_map
->infork
= 1;
3005 * XXX Note: upcalls are not copied.
3007 vm2
= vmspace_alloc(old_map
->min_offset
, old_map
->max_offset
);
3008 bcopy(&vm1
->vm_startcopy
, &vm2
->vm_startcopy
,
3009 (caddr_t
)&vm1
->vm_endcopy
- (caddr_t
)&vm1
->vm_startcopy
);
3010 new_map
= &vm2
->vm_map
; /* XXX */
3011 new_map
->timestamp
= 1;
3013 vm_map_lock(new_map
);
3016 old_entry
= old_map
->header
.next
;
3017 while (old_entry
!= &old_map
->header
) {
3019 old_entry
= old_entry
->next
;
3022 count
= vm_map_entry_reserve(count
+ MAP_RESERVE_COUNT
);
3024 old_entry
= old_map
->header
.next
;
3025 while (old_entry
!= &old_map
->header
) {
3026 if (old_entry
->maptype
== VM_MAPTYPE_SUBMAP
)
3027 panic("vm_map_fork: encountered a submap");
3029 switch (old_entry
->inheritance
) {
3030 case VM_INHERIT_NONE
:
3032 case VM_INHERIT_SHARE
:
3034 * Clone the entry, creating the shared object if
3037 object
= old_entry
->object
.vm_object
;
3038 if (object
== NULL
) {
3039 vm_map_entry_allocate_object(old_entry
);
3040 object
= old_entry
->object
.vm_object
;
3044 * Add the reference before calling vm_map_entry_shadow
3045 * to insure that a shadow object is created.
3047 vm_object_reference(object
);
3048 if (old_entry
->eflags
& MAP_ENTRY_NEEDS_COPY
) {
3049 vm_map_entry_shadow(old_entry
);
3050 /* Transfer the second reference too. */
3051 vm_object_reference(
3052 old_entry
->object
.vm_object
);
3053 vm_object_deallocate(object
);
3054 object
= old_entry
->object
.vm_object
;
3056 vm_object_clear_flag(object
, OBJ_ONEMAPPING
);
3059 * Clone the entry, referencing the shared object.
3061 new_entry
= vm_map_entry_create(new_map
, &count
);
3062 *new_entry
= *old_entry
;
3063 new_entry
->eflags
&= ~MAP_ENTRY_USER_WIRED
;
3064 new_entry
->wired_count
= 0;
3067 * Insert the entry into the new map -- we know we're
3068 * inserting at the end of the new map.
3071 vm_map_entry_link(new_map
, new_map
->header
.prev
,
3075 * Update the physical map
3077 pmap_copy(new_map
->pmap
, old_map
->pmap
,
3079 (old_entry
->end
- old_entry
->start
),
3082 case VM_INHERIT_COPY
:
3084 * Clone the entry and link into the map.
3086 new_entry
= vm_map_entry_create(new_map
, &count
);
3087 *new_entry
= *old_entry
;
3088 new_entry
->eflags
&= ~MAP_ENTRY_USER_WIRED
;
3089 new_entry
->wired_count
= 0;
3090 new_entry
->object
.vm_object
= NULL
;
3091 vm_map_entry_link(new_map
, new_map
->header
.prev
,
3093 vm_map_copy_entry(old_map
, new_map
, old_entry
,
3097 old_entry
= old_entry
->next
;
3100 new_map
->size
= old_map
->size
;
3101 old_map
->infork
= 0;
3102 vm_map_unlock(old_map
);
3103 vm_map_unlock(new_map
);
3104 vm_map_entry_release(count
);
3105 lwkt_reltoken(&vmspace_token
);
3106 lwkt_reltoken(&vm_token
);
3112 * Create an auto-grow stack entry
3117 vm_map_stack (vm_map_t map
, vm_offset_t addrbos
, vm_size_t max_ssize
,
3118 int flags
, vm_prot_t prot
, vm_prot_t max
, int cow
)
3120 vm_map_entry_t prev_entry
;
3121 vm_map_entry_t new_stack_entry
;
3122 vm_size_t init_ssize
;
3125 vm_offset_t tmpaddr
;
3127 cow
|= MAP_IS_STACK
;
3129 if (max_ssize
< sgrowsiz
)
3130 init_ssize
= max_ssize
;
3132 init_ssize
= sgrowsiz
;
3134 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
3138 * Find space for the mapping
3140 if ((flags
& (MAP_FIXED
| MAP_TRYFIXED
)) == 0) {
3141 if (vm_map_findspace(map
, addrbos
, max_ssize
, 1,
3144 vm_map_entry_release(count
);
3145 return (KERN_NO_SPACE
);
3150 /* If addr is already mapped, no go */
3151 if (vm_map_lookup_entry(map
, addrbos
, &prev_entry
)) {
3153 vm_map_entry_release(count
);
3154 return (KERN_NO_SPACE
);
3158 /* XXX already handled by kern_mmap() */
3159 /* If we would blow our VMEM resource limit, no go */
3160 if (map
->size
+ init_ssize
>
3161 curproc
->p_rlimit
[RLIMIT_VMEM
].rlim_cur
) {
3163 vm_map_entry_release(count
);
3164 return (KERN_NO_SPACE
);
3169 * If we can't accomodate max_ssize in the current mapping,
3170 * no go. However, we need to be aware that subsequent user
3171 * mappings might map into the space we have reserved for
3172 * stack, and currently this space is not protected.
3174 * Hopefully we will at least detect this condition
3175 * when we try to grow the stack.
3177 if ((prev_entry
->next
!= &map
->header
) &&
3178 (prev_entry
->next
->start
< addrbos
+ max_ssize
)) {
3180 vm_map_entry_release(count
);
3181 return (KERN_NO_SPACE
);
3185 * We initially map a stack of only init_ssize. We will
3186 * grow as needed later. Since this is to be a grow
3187 * down stack, we map at the top of the range.
3189 * Note: we would normally expect prot and max to be
3190 * VM_PROT_ALL, and cow to be 0. Possibly we should
3191 * eliminate these as input parameters, and just
3192 * pass these values here in the insert call.
3194 rv
= vm_map_insert(map
, &count
,
3195 NULL
, 0, addrbos
+ max_ssize
- init_ssize
,
3196 addrbos
+ max_ssize
,
3201 /* Now set the avail_ssize amount */
3202 if (rv
== KERN_SUCCESS
) {
3203 if (prev_entry
!= &map
->header
)
3204 vm_map_clip_end(map
, prev_entry
, addrbos
+ max_ssize
- init_ssize
, &count
);
3205 new_stack_entry
= prev_entry
->next
;
3206 if (new_stack_entry
->end
!= addrbos
+ max_ssize
||
3207 new_stack_entry
->start
!= addrbos
+ max_ssize
- init_ssize
)
3208 panic ("Bad entry start/end for new stack entry");
3210 new_stack_entry
->aux
.avail_ssize
= max_ssize
- init_ssize
;
3214 vm_map_entry_release(count
);
3219 * Attempts to grow a vm stack entry. Returns KERN_SUCCESS if the
3220 * desired address is already mapped, or if we successfully grow
3221 * the stack. Also returns KERN_SUCCESS if addr is outside the
3222 * stack range (this is strange, but preserves compatibility with
3223 * the grow function in vm_machdep.c).
3228 vm_map_growstack (struct proc
*p
, vm_offset_t addr
)
3230 vm_map_entry_t prev_entry
;
3231 vm_map_entry_t stack_entry
;
3232 vm_map_entry_t new_stack_entry
;
3233 struct vmspace
*vm
= p
->p_vmspace
;
3234 vm_map_t map
= &vm
->vm_map
;
3237 int rv
= KERN_SUCCESS
;
3239 int use_read_lock
= 1;
3242 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
3245 vm_map_lock_read(map
);
3249 /* If addr is already in the entry range, no need to grow.*/
3250 if (vm_map_lookup_entry(map
, addr
, &prev_entry
))
3253 if ((stack_entry
= prev_entry
->next
) == &map
->header
)
3255 if (prev_entry
== &map
->header
)
3256 end
= stack_entry
->start
- stack_entry
->aux
.avail_ssize
;
3258 end
= prev_entry
->end
;
3261 * This next test mimics the old grow function in vm_machdep.c.
3262 * It really doesn't quite make sense, but we do it anyway
3263 * for compatibility.
3265 * If not growable stack, return success. This signals the
3266 * caller to proceed as he would normally with normal vm.
3268 if (stack_entry
->aux
.avail_ssize
< 1 ||
3269 addr
>= stack_entry
->start
||
3270 addr
< stack_entry
->start
- stack_entry
->aux
.avail_ssize
) {
3274 /* Find the minimum grow amount */
3275 grow_amount
= roundup (stack_entry
->start
- addr
, PAGE_SIZE
);
3276 if (grow_amount
> stack_entry
->aux
.avail_ssize
) {
3282 * If there is no longer enough space between the entries
3283 * nogo, and adjust the available space. Note: this
3284 * should only happen if the user has mapped into the
3285 * stack area after the stack was created, and is
3286 * probably an error.
3288 * This also effectively destroys any guard page the user
3289 * might have intended by limiting the stack size.
3291 if (grow_amount
> stack_entry
->start
- end
) {
3292 if (use_read_lock
&& vm_map_lock_upgrade(map
)) {
3297 stack_entry
->aux
.avail_ssize
= stack_entry
->start
- end
;
3302 is_procstack
= addr
>= (vm_offset_t
)vm
->vm_maxsaddr
;
3304 /* If this is the main process stack, see if we're over the
3307 if (is_procstack
&& (ctob(vm
->vm_ssize
) + grow_amount
>
3308 p
->p_rlimit
[RLIMIT_STACK
].rlim_cur
)) {
3313 /* Round up the grow amount modulo SGROWSIZ */
3314 grow_amount
= roundup (grow_amount
, sgrowsiz
);
3315 if (grow_amount
> stack_entry
->aux
.avail_ssize
) {
3316 grow_amount
= stack_entry
->aux
.avail_ssize
;
3318 if (is_procstack
&& (ctob(vm
->vm_ssize
) + grow_amount
>
3319 p
->p_rlimit
[RLIMIT_STACK
].rlim_cur
)) {
3320 grow_amount
= p
->p_rlimit
[RLIMIT_STACK
].rlim_cur
-
3324 /* If we would blow our VMEM resource limit, no go */
3325 if (map
->size
+ grow_amount
> p
->p_rlimit
[RLIMIT_VMEM
].rlim_cur
) {
3330 if (use_read_lock
&& vm_map_lock_upgrade(map
)) {
3336 /* Get the preliminary new entry start value */
3337 addr
= stack_entry
->start
- grow_amount
;
3339 /* If this puts us into the previous entry, cut back our growth
3340 * to the available space. Also, see the note above.
3343 stack_entry
->aux
.avail_ssize
= stack_entry
->start
- end
;
3347 rv
= vm_map_insert(map
, &count
,
3348 NULL
, 0, addr
, stack_entry
->start
,
3350 VM_PROT_ALL
, VM_PROT_ALL
,
3353 /* Adjust the available stack space by the amount we grew. */
3354 if (rv
== KERN_SUCCESS
) {
3355 if (prev_entry
!= &map
->header
)
3356 vm_map_clip_end(map
, prev_entry
, addr
, &count
);
3357 new_stack_entry
= prev_entry
->next
;
3358 if (new_stack_entry
->end
!= stack_entry
->start
||
3359 new_stack_entry
->start
!= addr
)
3360 panic ("Bad stack grow start/end in new stack entry");
3362 new_stack_entry
->aux
.avail_ssize
=
3363 stack_entry
->aux
.avail_ssize
-
3364 (new_stack_entry
->end
- new_stack_entry
->start
);
3366 vm
->vm_ssize
+= btoc(new_stack_entry
->end
-
3367 new_stack_entry
->start
);
3373 vm_map_unlock_read(map
);
3376 vm_map_entry_release(count
);
3381 * Unshare the specified VM space for exec. If other processes are
3382 * mapped to it, then create a new one. The new vmspace is null.
3387 vmspace_exec(struct proc
*p
, struct vmspace
*vmcopy
)
3389 struct vmspace
*oldvmspace
= p
->p_vmspace
;
3390 struct vmspace
*newvmspace
;
3391 vm_map_t map
= &p
->p_vmspace
->vm_map
;
3394 * If we are execing a resident vmspace we fork it, otherwise
3395 * we create a new vmspace. Note that exitingcnt and upcalls
3396 * are not copied to the new vmspace.
3398 lwkt_gettoken(&vmspace_token
);
3400 newvmspace
= vmspace_fork(vmcopy
);
3402 newvmspace
= vmspace_alloc(map
->min_offset
, map
->max_offset
);
3403 bcopy(&oldvmspace
->vm_startcopy
, &newvmspace
->vm_startcopy
,
3404 (caddr_t
)&oldvmspace
->vm_endcopy
-
3405 (caddr_t
)&oldvmspace
->vm_startcopy
);
3409 * Finish initializing the vmspace before assigning it
3410 * to the process. The vmspace will become the current vmspace
3413 pmap_pinit2(vmspace_pmap(newvmspace
));
3414 pmap_replacevm(p
, newvmspace
, 0);
3415 sysref_put(&oldvmspace
->vm_sysref
);
3416 lwkt_reltoken(&vmspace_token
);
3420 * Unshare the specified VM space for forcing COW. This
3421 * is called by rfork, for the (RFMEM|RFPROC) == 0 case.
3423 * The exitingcnt test is not strictly necessary but has been
3424 * included for code sanity (to make the code a bit more deterministic).
3427 vmspace_unshare(struct proc
*p
)
3429 struct vmspace
*oldvmspace
= p
->p_vmspace
;
3430 struct vmspace
*newvmspace
;
3432 lwkt_gettoken(&vmspace_token
);
3433 if (oldvmspace
->vm_sysref
.refcnt
== 1 && oldvmspace
->vm_exitingcnt
== 0)
3435 newvmspace
= vmspace_fork(oldvmspace
);
3436 pmap_pinit2(vmspace_pmap(newvmspace
));
3437 pmap_replacevm(p
, newvmspace
, 0);
3438 sysref_put(&oldvmspace
->vm_sysref
);
3439 lwkt_reltoken(&vmspace_token
);
3443 * Finds the VM object, offset, and protection for a given virtual address
3444 * in the specified map, assuming a page fault of the type specified.
3446 * Leaves the map in question locked for read; return values are guaranteed
3447 * until a vm_map_lookup_done call is performed. Note that the map argument
3448 * is in/out; the returned map must be used in the call to vm_map_lookup_done.
3450 * A handle (out_entry) is returned for use in vm_map_lookup_done, to make
3453 * If a lookup is requested with "write protection" specified, the map may
3454 * be changed to perform virtual copying operations, although the data
3455 * referenced will remain the same.
3460 vm_map_lookup(vm_map_t
*var_map
, /* IN/OUT */
3462 vm_prot_t fault_typea
,
3463 vm_map_entry_t
*out_entry
, /* OUT */
3464 vm_object_t
*object
, /* OUT */
3465 vm_pindex_t
*pindex
, /* OUT */
3466 vm_prot_t
*out_prot
, /* OUT */
3467 boolean_t
*wired
) /* OUT */
3469 vm_map_entry_t entry
;
3470 vm_map_t map
= *var_map
;
3472 vm_prot_t fault_type
= fault_typea
;
3473 int use_read_lock
= 1;
3474 int rv
= KERN_SUCCESS
;
3478 vm_map_lock_read(map
);
3483 * If the map has an interesting hint, try it before calling full
3484 * blown lookup routine.
3489 if ((entry
== &map
->header
) ||
3490 (vaddr
< entry
->start
) || (vaddr
>= entry
->end
)) {
3491 vm_map_entry_t tmp_entry
;
3494 * Entry was either not a valid hint, or the vaddr was not
3495 * contained in the entry, so do a full lookup.
3497 if (!vm_map_lookup_entry(map
, vaddr
, &tmp_entry
)) {
3498 rv
= KERN_INVALID_ADDRESS
;
3509 if (entry
->maptype
== VM_MAPTYPE_SUBMAP
) {
3510 vm_map_t old_map
= map
;
3512 *var_map
= map
= entry
->object
.sub_map
;
3514 vm_map_unlock_read(old_map
);
3516 vm_map_unlock(old_map
);
3522 * Check whether this task is allowed to have this page.
3523 * Note the special case for MAP_ENTRY_COW
3524 * pages with an override. This is to implement a forced
3525 * COW for debuggers.
3528 if (fault_type
& VM_PROT_OVERRIDE_WRITE
)
3529 prot
= entry
->max_protection
;
3531 prot
= entry
->protection
;
3533 fault_type
&= (VM_PROT_READ
|VM_PROT_WRITE
|VM_PROT_EXECUTE
);
3534 if ((fault_type
& prot
) != fault_type
) {
3535 rv
= KERN_PROTECTION_FAILURE
;
3539 if ((entry
->eflags
& MAP_ENTRY_USER_WIRED
) &&
3540 (entry
->eflags
& MAP_ENTRY_COW
) &&
3541 (fault_type
& VM_PROT_WRITE
) &&
3542 (fault_typea
& VM_PROT_OVERRIDE_WRITE
) == 0) {
3543 rv
= KERN_PROTECTION_FAILURE
;
3548 * If this page is not pageable, we have to get it for all possible
3551 *wired
= (entry
->wired_count
!= 0);
3553 prot
= fault_type
= entry
->protection
;
3556 * Virtual page tables may need to update the accessed (A) bit
3557 * in a page table entry. Upgrade the fault to a write fault for
3558 * that case if the map will support it. If the map does not support
3559 * it the page table entry simply will not be updated.
3561 if (entry
->maptype
== VM_MAPTYPE_VPAGETABLE
) {
3562 if (prot
& VM_PROT_WRITE
)
3563 fault_type
|= VM_PROT_WRITE
;
3567 * If the entry was copy-on-write, we either ...
3569 if (entry
->eflags
& MAP_ENTRY_NEEDS_COPY
) {
3571 * If we want to write the page, we may as well handle that
3572 * now since we've got the map locked.
3574 * If we don't need to write the page, we just demote the
3575 * permissions allowed.
3578 if (fault_type
& VM_PROT_WRITE
) {
3580 * Make a new object, and place it in the object
3581 * chain. Note that no new references have appeared
3582 * -- one just moved from the map to the new
3586 if (use_read_lock
&& vm_map_lock_upgrade(map
)) {
3592 vm_map_entry_shadow(entry
);
3595 * We're attempting to read a copy-on-write page --
3596 * don't allow writes.
3599 prot
&= ~VM_PROT_WRITE
;
3604 * Create an object if necessary.
3606 if (entry
->object
.vm_object
== NULL
&&
3608 if (use_read_lock
&& vm_map_lock_upgrade(map
)) {
3613 vm_map_entry_allocate_object(entry
);
3617 * Return the object/offset from this entry. If the entry was
3618 * copy-on-write or empty, it has been fixed up.
3621 *pindex
= OFF_TO_IDX((vaddr
- entry
->start
) + entry
->offset
);
3622 *object
= entry
->object
.vm_object
;
3625 * Return whether this is the only map sharing this data. On
3626 * success we return with a read lock held on the map. On failure
3627 * we return with the map unlocked.
3631 if (rv
== KERN_SUCCESS
) {
3632 if (use_read_lock
== 0)
3633 vm_map_lock_downgrade(map
);
3634 } else if (use_read_lock
) {
3635 vm_map_unlock_read(map
);
3643 * Releases locks acquired by a vm_map_lookup()
3644 * (according to the handle returned by that lookup).
3646 * No other requirements.
3649 vm_map_lookup_done(vm_map_t map
, vm_map_entry_t entry
, int count
)
3652 * Unlock the main-level map
3654 vm_map_unlock_read(map
);
3656 vm_map_entry_release(count
);
3659 #include "opt_ddb.h"
3661 #include <sys/kernel.h>
3663 #include <ddb/ddb.h>
3668 DB_SHOW_COMMAND(map
, vm_map_print
)
3671 /* XXX convert args. */
3672 vm_map_t map
= (vm_map_t
)addr
;
3673 boolean_t full
= have_addr
;
3675 vm_map_entry_t entry
;
3677 db_iprintf("Task map %p: pmap=%p, nentries=%d, version=%u\n",
3679 (void *)map
->pmap
, map
->nentries
, map
->timestamp
);
3682 if (!full
&& db_indent
)
3686 for (entry
= map
->header
.next
; entry
!= &map
->header
;
3687 entry
= entry
->next
) {
3688 db_iprintf("map entry %p: start=%p, end=%p\n",
3689 (void *)entry
, (void *)entry
->start
, (void *)entry
->end
);
3692 static char *inheritance_name
[4] =
3693 {"share", "copy", "none", "donate_copy"};
3695 db_iprintf(" prot=%x/%x/%s",
3697 entry
->max_protection
,
3698 inheritance_name
[(int)(unsigned char)entry
->inheritance
]);
3699 if (entry
->wired_count
!= 0)
3700 db_printf(", wired");
3702 if (entry
->maptype
== VM_MAPTYPE_SUBMAP
) {
3703 /* XXX no %qd in kernel. Truncate entry->offset. */
3704 db_printf(", share=%p, offset=0x%lx\n",
3705 (void *)entry
->object
.sub_map
,
3706 (long)entry
->offset
);
3708 if ((entry
->prev
== &map
->header
) ||
3709 (entry
->prev
->object
.sub_map
!=
3710 entry
->object
.sub_map
)) {
3712 vm_map_print((db_expr_t
)(intptr_t)
3713 entry
->object
.sub_map
,
3718 /* XXX no %qd in kernel. Truncate entry->offset. */
3719 db_printf(", object=%p, offset=0x%lx",
3720 (void *)entry
->object
.vm_object
,
3721 (long)entry
->offset
);
3722 if (entry
->eflags
& MAP_ENTRY_COW
)
3723 db_printf(", copy (%s)",
3724 (entry
->eflags
& MAP_ENTRY_NEEDS_COPY
) ? "needed" : "done");
3728 if ((entry
->prev
== &map
->header
) ||
3729 (entry
->prev
->object
.vm_object
!=
3730 entry
->object
.vm_object
)) {
3732 vm_object_print((db_expr_t
)(intptr_t)
3733 entry
->object
.vm_object
,
3748 DB_SHOW_COMMAND(procvm
, procvm
)
3753 p
= (struct proc
*) addr
;
3758 db_printf("p = %p, vmspace = %p, map = %p, pmap = %p\n",
3759 (void *)p
, (void *)p
->p_vmspace
, (void *)&p
->p_vmspace
->vm_map
,
3760 (void *)vmspace_pmap(p
->p_vmspace
));
3762 vm_map_print((db_expr_t
)(intptr_t)&p
->p_vmspace
->vm_map
, 1, 0, NULL
);