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. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * from: @(#)vm_map.c 8.3 (Berkeley) 1/12/94
37 * Copyright (c) 1987, 1990 Carnegie-Mellon University.
38 * All rights reserved.
40 * Authors: Avadis Tevanian, Jr., Michael Wayne Young
42 * Permission to use, copy, modify and distribute this software and
43 * its documentation is hereby granted, provided that both the copyright
44 * notice and this permission notice appear in all copies of the
45 * software, derivative works or modified versions, and any portions
46 * thereof, and that both notices appear in supporting documentation.
48 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
49 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
50 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
52 * Carnegie Mellon requests users of this software to return to
54 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
55 * School of Computer Science
56 * Carnegie Mellon University
57 * Pittsburgh PA 15213-3890
59 * any improvements or extensions that they make and grant Carnegie the
60 * rights to redistribute these changes.
62 * $FreeBSD: src/sys/vm/vm_map.c,v 1.187.2.19 2003/05/27 00:47:02 alc Exp $
66 * Virtual memory mapping module.
69 #include <sys/param.h>
70 #include <sys/systm.h>
71 #include <sys/kernel.h>
73 #include <sys/serialize.h>
75 #include <sys/vmmeter.h>
77 #include <sys/vnode.h>
78 #include <sys/resourcevar.h>
81 #include <sys/malloc.h>
82 #include <sys/objcache.h>
85 #include <vm/vm_param.h>
87 #include <vm/vm_map.h>
88 #include <vm/vm_page.h>
89 #include <vm/vm_object.h>
90 #include <vm/vm_pager.h>
91 #include <vm/vm_kern.h>
92 #include <vm/vm_extern.h>
93 #include <vm/swap_pager.h>
94 #include <vm/vm_zone.h>
96 #include <sys/random.h>
97 #include <sys/sysctl.h>
98 #include <sys/spinlock.h>
100 #include <sys/thread2.h>
101 #include <sys/spinlock2.h>
104 * Virtual memory maps provide for the mapping, protection, and sharing
105 * of virtual memory objects. In addition, this module provides for an
106 * efficient virtual copy of memory from one map to another.
108 * Synchronization is required prior to most operations.
110 * Maps consist of an ordered doubly-linked list of simple entries.
111 * A hint and a RB tree is used to speed-up lookups.
113 * Callers looking to modify maps specify start/end addresses which cause
114 * the related map entry to be clipped if necessary, and then later
115 * recombined if the pieces remained compatible.
117 * Virtual copy operations are performed by copying VM object references
118 * from one map to another, and then marking both regions as copy-on-write.
120 static boolean_t
vmspace_ctor(void *obj
, void *privdata
, int ocflags
);
121 static void vmspace_dtor(void *obj
, void *privdata
);
122 static void vmspace_terminate(struct vmspace
*vm
, int final
);
124 MALLOC_DEFINE(M_VMSPACE
, "vmspace", "vmspace objcache backingstore");
125 static struct objcache
*vmspace_cache
;
128 * per-cpu page table cross mappings are initialized in early boot
129 * and might require a considerable number of vm_map_entry structures.
131 #define MAPENTRYBSP_CACHE (MAXCPU+1)
132 #define MAPENTRYAP_CACHE 8
134 static struct vm_zone mapentzone_store
;
135 static vm_zone_t mapentzone
;
137 static struct vm_map_entry map_entry_init
[MAX_MAPENT
];
138 static struct vm_map_entry cpu_map_entry_init_bsp
[MAPENTRYBSP_CACHE
];
139 static struct vm_map_entry cpu_map_entry_init_ap
[MAXCPU
][MAPENTRYAP_CACHE
];
141 static int randomize_mmap
;
142 SYSCTL_INT(_vm
, OID_AUTO
, randomize_mmap
, CTLFLAG_RW
, &randomize_mmap
, 0,
143 "Randomize mmap offsets");
144 static int vm_map_relock_enable
= 1;
145 SYSCTL_INT(_vm
, OID_AUTO
, map_relock_enable
, CTLFLAG_RW
,
146 &vm_map_relock_enable
, 0, "Randomize mmap offsets");
148 static void vmspace_drop_notoken(struct vmspace
*vm
);
149 static void vm_map_entry_shadow(vm_map_entry_t entry
, int addref
);
150 static vm_map_entry_t
vm_map_entry_create(vm_map_t map
, int *);
151 static void vm_map_entry_dispose (vm_map_t map
, vm_map_entry_t entry
, int *);
152 static void _vm_map_clip_end (vm_map_t
, vm_map_entry_t
, vm_offset_t
, int *);
153 static void _vm_map_clip_start (vm_map_t
, vm_map_entry_t
, vm_offset_t
, int *);
154 static void vm_map_entry_delete (vm_map_t
, vm_map_entry_t
, int *);
155 static void vm_map_entry_unwire (vm_map_t
, vm_map_entry_t
);
156 static void vm_map_copy_entry (vm_map_t
, vm_map_t
, vm_map_entry_t
,
158 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
);
161 * Initialize the vm_map module. Must be called before any other vm_map
164 * Map and entry structures are allocated from the general purpose
165 * memory pool with some exceptions:
167 * - The kernel map is allocated statically.
168 * - Initial kernel map entries are allocated out of a static pool.
169 * - We must set ZONE_SPECIAL here or the early boot code can get
170 * stuck if there are >63 cores.
172 * These restrictions are necessary since malloc() uses the
173 * maps and requires map entries.
175 * Called from the low level boot code only.
180 mapentzone
= &mapentzone_store
;
181 zbootinit(mapentzone
, "MAP ENTRY", sizeof (struct vm_map_entry
),
182 map_entry_init
, MAX_MAPENT
);
183 mapentzone_store
.zflags
|= ZONE_SPECIAL
;
187 * Called prior to any vmspace allocations.
189 * Called from the low level boot code only.
194 vmspace_cache
= objcache_create_mbacked(M_VMSPACE
,
195 sizeof(struct vmspace
),
197 vmspace_ctor
, vmspace_dtor
,
199 zinitna(mapentzone
, NULL
, 0, 0, ZONE_USE_RESERVE
| ZONE_SPECIAL
);
205 * objcache support. We leave the pmap root cached as long as possible
206 * for performance reasons.
210 vmspace_ctor(void *obj
, void *privdata
, int ocflags
)
212 struct vmspace
*vm
= obj
;
214 bzero(vm
, sizeof(*vm
));
215 vm
->vm_refcnt
= VM_REF_DELETED
;
222 vmspace_dtor(void *obj
, void *privdata
)
224 struct vmspace
*vm
= obj
;
226 KKASSERT(vm
->vm_refcnt
== VM_REF_DELETED
);
227 pmap_puninit(vmspace_pmap(vm
));
231 * Red black tree functions
233 * The caller must hold the related map lock.
235 static int rb_vm_map_compare(vm_map_entry_t a
, vm_map_entry_t b
);
236 RB_GENERATE(vm_map_rb_tree
, vm_map_entry
, rb_entry
, rb_vm_map_compare
);
238 /* a->start is address, and the only field has to be initialized */
240 rb_vm_map_compare(vm_map_entry_t a
, vm_map_entry_t b
)
242 if (a
->start
< b
->start
)
244 else if (a
->start
> b
->start
)
250 * Initialize vmspace ref/hold counts vmspace0. There is a holdcnt for
254 vmspace_initrefs(struct vmspace
*vm
)
261 * Allocate a vmspace structure, including a vm_map and pmap.
262 * Initialize numerous fields. While the initial allocation is zerod,
263 * subsequence reuse from the objcache leaves elements of the structure
264 * intact (particularly the pmap), so portions must be zerod.
266 * Returns a referenced vmspace.
271 vmspace_alloc(vm_offset_t min
, vm_offset_t max
)
275 vm
= objcache_get(vmspace_cache
, M_WAITOK
);
277 bzero(&vm
->vm_startcopy
,
278 (char *)&vm
->vm_endcopy
- (char *)&vm
->vm_startcopy
);
279 vm_map_init(&vm
->vm_map
, min
, max
, NULL
); /* initializes token */
282 * NOTE: hold to acquires token for safety.
284 * On return vmspace is referenced (refs=1, hold=1). That is,
285 * each refcnt also has a holdcnt. There can be additional holds
286 * (holdcnt) above and beyond the refcnt. Finalization is handled in
287 * two stages, one on refs 1->0, and the the second on hold 1->0.
289 KKASSERT(vm
->vm_holdcnt
== 0);
290 KKASSERT(vm
->vm_refcnt
== VM_REF_DELETED
);
291 vmspace_initrefs(vm
);
293 pmap_pinit(vmspace_pmap(vm
)); /* (some fields reused) */
294 vm
->vm_map
.pmap
= vmspace_pmap(vm
); /* XXX */
297 cpu_vmspace_alloc(vm
);
304 * NOTE: Can return 0 if the vmspace is exiting.
307 vmspace_getrefs(struct vmspace
*vm
)
313 if (n
& VM_REF_DELETED
)
319 vmspace_hold(struct vmspace
*vm
)
321 atomic_add_int(&vm
->vm_holdcnt
, 1);
322 lwkt_gettoken(&vm
->vm_map
.token
);
326 * Drop with final termination interlock.
329 vmspace_drop(struct vmspace
*vm
)
331 lwkt_reltoken(&vm
->vm_map
.token
);
332 vmspace_drop_notoken(vm
);
336 vmspace_drop_notoken(struct vmspace
*vm
)
338 if (atomic_fetchadd_int(&vm
->vm_holdcnt
, -1) == 1) {
339 if (vm
->vm_refcnt
& VM_REF_DELETED
)
340 vmspace_terminate(vm
, 1);
345 * A vmspace object must not be in a terminated state to be able to obtain
346 * additional refs on it.
348 * These are official references to the vmspace, the count is used to check
349 * for vmspace sharing. Foreign accessors should use 'hold' and not 'ref'.
351 * XXX we need to combine hold & ref together into one 64-bit field to allow
352 * holds to prevent stage-1 termination.
355 vmspace_ref(struct vmspace
*vm
)
359 atomic_add_int(&vm
->vm_holdcnt
, 1);
360 n
= atomic_fetchadd_int(&vm
->vm_refcnt
, 1);
361 KKASSERT((n
& VM_REF_DELETED
) == 0);
365 * Release a ref on the vmspace. On the 1->0 transition we do stage-1
366 * termination of the vmspace. Then, on the final drop of the hold we
367 * will do stage-2 final termination.
370 vmspace_rel(struct vmspace
*vm
)
375 * Drop refs. Each ref also has a hold which is also dropped.
377 * When refs hits 0 compete to get the VM_REF_DELETED flag (hold
378 * prevent finalization) to start termination processing.
379 * Finalization occurs when the last hold count drops to 0.
381 n
= atomic_fetchadd_int(&vm
->vm_refcnt
, -1) - 1;
383 if (atomic_cmpset_int(&vm
->vm_refcnt
, 0, VM_REF_DELETED
)) {
384 vmspace_terminate(vm
, 0);
390 vmspace_drop_notoken(vm
);
394 * This is called during exit indicating that the vmspace is no
395 * longer in used by an exiting process, but the process has not yet
398 * We drop refs, allowing for stage-1 termination, but maintain a holdcnt
399 * to prevent stage-2 until the process is reaped. Note hte order of
400 * operation, we must hold first.
405 vmspace_relexit(struct vmspace
*vm
)
407 atomic_add_int(&vm
->vm_holdcnt
, 1);
412 * Called during reap to disconnect the remainder of the vmspace from
413 * the process. On the hold drop the vmspace termination is finalized.
418 vmspace_exitfree(struct proc
*p
)
424 vmspace_drop_notoken(vm
);
428 * Called in two cases:
430 * (1) When the last refcnt is dropped and the vmspace becomes inactive,
431 * called with final == 0. refcnt will be (u_int)-1 at this point,
432 * and holdcnt will still be non-zero.
434 * (2) When holdcnt becomes 0, called with final == 1. There should no
435 * longer be anyone with access to the vmspace.
437 * VMSPACE_EXIT1 flags the primary deactivation
438 * VMSPACE_EXIT2 flags the last reap
441 vmspace_terminate(struct vmspace
*vm
, int final
)
445 lwkt_gettoken(&vm
->vm_map
.token
);
447 KKASSERT((vm
->vm_flags
& VMSPACE_EXIT1
) == 0);
448 vm
->vm_flags
|= VMSPACE_EXIT1
;
451 * Get rid of most of the resources. Leave the kernel pmap
454 * If the pmap does not contain wired pages we can bulk-delete
455 * the pmap as a performance optimization before removing the
458 * If the pmap contains wired pages we cannot do this
459 * pre-optimization because currently vm_fault_unwire()
460 * expects the pmap pages to exist and will not decrement
461 * p->wire_count if they do not.
464 if (vmspace_pmap(vm
)->pm_stats
.wired_count
) {
465 vm_map_remove(&vm
->vm_map
, VM_MIN_USER_ADDRESS
,
466 VM_MAX_USER_ADDRESS
);
467 pmap_remove_pages(vmspace_pmap(vm
), VM_MIN_USER_ADDRESS
,
468 VM_MAX_USER_ADDRESS
);
470 pmap_remove_pages(vmspace_pmap(vm
), VM_MIN_USER_ADDRESS
,
471 VM_MAX_USER_ADDRESS
);
472 vm_map_remove(&vm
->vm_map
, VM_MIN_USER_ADDRESS
,
473 VM_MAX_USER_ADDRESS
);
475 lwkt_reltoken(&vm
->vm_map
.token
);
477 KKASSERT((vm
->vm_flags
& VMSPACE_EXIT1
) != 0);
478 KKASSERT((vm
->vm_flags
& VMSPACE_EXIT2
) == 0);
481 * Get rid of remaining basic resources.
483 vm
->vm_flags
|= VMSPACE_EXIT2
;
486 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
487 vm_map_lock(&vm
->vm_map
);
488 cpu_vmspace_free(vm
);
491 * Lock the map, to wait out all other references to it.
492 * Delete all of the mappings and pages they hold, then call
493 * the pmap module to reclaim anything left.
495 vm_map_delete(&vm
->vm_map
, vm
->vm_map
.min_offset
,
496 vm
->vm_map
.max_offset
, &count
);
497 vm_map_unlock(&vm
->vm_map
);
498 vm_map_entry_release(count
);
500 pmap_release(vmspace_pmap(vm
));
501 lwkt_reltoken(&vm
->vm_map
.token
);
502 objcache_put(vmspace_cache
, vm
);
507 * Swap useage is determined by taking the proportional swap used by
508 * VM objects backing the VM map. To make up for fractional losses,
509 * if the VM object has any swap use at all the associated map entries
510 * count for at least 1 swap page.
515 vmspace_swap_count(struct vmspace
*vm
)
517 vm_map_t map
= &vm
->vm_map
;
520 vm_offset_t count
= 0;
524 for (cur
= map
->header
.next
; cur
!= &map
->header
; cur
= cur
->next
) {
525 switch(cur
->maptype
) {
526 case VM_MAPTYPE_NORMAL
:
527 case VM_MAPTYPE_VPAGETABLE
:
528 if ((object
= cur
->object
.vm_object
) == NULL
)
530 if (object
->swblock_count
) {
531 n
= (cur
->end
- cur
->start
) / PAGE_SIZE
;
532 count
+= object
->swblock_count
*
533 SWAP_META_PAGES
* n
/ object
->size
+ 1;
546 * Calculate the approximate number of anonymous pages in use by
547 * this vmspace. To make up for fractional losses, we count each
548 * VM object as having at least 1 anonymous page.
553 vmspace_anonymous_count(struct vmspace
*vm
)
555 vm_map_t map
= &vm
->vm_map
;
558 vm_offset_t count
= 0;
561 for (cur
= map
->header
.next
; cur
!= &map
->header
; cur
= cur
->next
) {
562 switch(cur
->maptype
) {
563 case VM_MAPTYPE_NORMAL
:
564 case VM_MAPTYPE_VPAGETABLE
:
565 if ((object
= cur
->object
.vm_object
) == NULL
)
567 if (object
->type
!= OBJT_DEFAULT
&&
568 object
->type
!= OBJT_SWAP
) {
571 count
+= object
->resident_page_count
;
583 * Initialize an existing vm_map structure such as that in the vmspace
584 * structure. The pmap is initialized elsewhere.
589 vm_map_init(struct vm_map
*map
, vm_offset_t min
, vm_offset_t max
, pmap_t pmap
)
591 map
->header
.next
= map
->header
.prev
= &map
->header
;
592 RB_INIT(&map
->rb_root
);
593 spin_init(&map
->ilock_spin
, "ilock");
594 map
->ilock_base
= NULL
;
598 map
->min_offset
= min
;
599 map
->max_offset
= max
;
601 map
->first_free
= &map
->header
;
602 map
->hint
= &map
->header
;
605 lwkt_token_init(&map
->token
, "vm_map");
606 lockinit(&map
->lock
, "vm_maplk", (hz
+ 9) / 10, 0);
610 * Shadow the vm_map_entry's object. This typically needs to be done when
611 * a write fault is taken on an entry which had previously been cloned by
612 * fork(). The shared object (which might be NULL) must become private so
613 * we add a shadow layer above it.
615 * Object allocation for anonymous mappings is defered as long as possible.
616 * When creating a shadow, however, the underlying object must be instantiated
617 * so it can be shared.
619 * If the map segment is governed by a virtual page table then it is
620 * possible to address offsets beyond the mapped area. Just allocate
621 * a maximally sized object for this case.
623 * If addref is non-zero an additional reference is added to the returned
624 * entry. This mechanic exists because the additional reference might have
625 * to be added atomically and not after return to prevent a premature
628 * The vm_map must be exclusively locked.
629 * No other requirements.
633 vm_map_entry_shadow(vm_map_entry_t entry
, int addref
)
635 if (entry
->maptype
== VM_MAPTYPE_VPAGETABLE
) {
636 vm_object_shadow(&entry
->object
.vm_object
, &entry
->offset
,
637 0x7FFFFFFF, addref
); /* XXX */
639 vm_object_shadow(&entry
->object
.vm_object
, &entry
->offset
,
640 atop(entry
->end
- entry
->start
), addref
);
642 entry
->eflags
&= ~MAP_ENTRY_NEEDS_COPY
;
646 * Allocate an object for a vm_map_entry.
648 * Object allocation for anonymous mappings is defered as long as possible.
649 * This function is called when we can defer no longer, generally when a map
650 * entry might be split or forked or takes a page fault.
652 * If the map segment is governed by a virtual page table then it is
653 * possible to address offsets beyond the mapped area. Just allocate
654 * a maximally sized object for this case.
656 * The vm_map must be exclusively locked.
657 * No other requirements.
660 vm_map_entry_allocate_object(vm_map_entry_t entry
)
664 if (entry
->maptype
== VM_MAPTYPE_VPAGETABLE
) {
665 obj
= vm_object_allocate(OBJT_DEFAULT
, 0x7FFFFFFF); /* XXX */
667 obj
= vm_object_allocate(OBJT_DEFAULT
,
668 atop(entry
->end
- entry
->start
));
670 entry
->object
.vm_object
= obj
;
675 * Set an initial negative count so the first attempt to reserve
676 * space preloads a bunch of vm_map_entry's for this cpu. Also
677 * pre-allocate 2 vm_map_entries which will be needed by zalloc() to
678 * map a new page for vm_map_entry structures. SMP systems are
679 * particularly sensitive.
681 * This routine is called in early boot so we cannot just call
682 * vm_map_entry_reserve().
684 * Called from the low level boot code only (for each cpu)
686 * WARNING! Take care not to have too-big a static/BSS structure here
687 * as MAXCPU can be 256+, otherwise the loader's 64MB heap
688 * can get blown out by the kernel plus the initrd image.
691 vm_map_entry_reserve_cpu_init(globaldata_t gd
)
693 vm_map_entry_t entry
;
697 gd
->gd_vme_avail
-= MAP_RESERVE_COUNT
* 2;
698 if (gd
->gd_cpuid
== 0) {
699 entry
= &cpu_map_entry_init_bsp
[0];
700 count
= MAPENTRYBSP_CACHE
;
702 entry
= &cpu_map_entry_init_ap
[gd
->gd_cpuid
][0];
703 count
= MAPENTRYAP_CACHE
;
705 for (i
= 0; i
< count
; ++i
, ++entry
) {
706 entry
->next
= gd
->gd_vme_base
;
707 gd
->gd_vme_base
= entry
;
712 * Reserves vm_map_entry structures so code later on can manipulate
713 * map_entry structures within a locked map without blocking trying
714 * to allocate a new vm_map_entry.
719 vm_map_entry_reserve(int count
)
721 struct globaldata
*gd
= mycpu
;
722 vm_map_entry_t entry
;
725 * Make sure we have enough structures in gd_vme_base to handle
726 * the reservation request.
728 * The critical section protects access to the per-cpu gd.
731 while (gd
->gd_vme_avail
< count
) {
732 entry
= zalloc(mapentzone
);
733 entry
->next
= gd
->gd_vme_base
;
734 gd
->gd_vme_base
= entry
;
737 gd
->gd_vme_avail
-= count
;
744 * Releases previously reserved vm_map_entry structures that were not
745 * used. If we have too much junk in our per-cpu cache clean some of
751 vm_map_entry_release(int count
)
753 struct globaldata
*gd
= mycpu
;
754 vm_map_entry_t entry
;
757 gd
->gd_vme_avail
+= count
;
758 while (gd
->gd_vme_avail
> MAP_RESERVE_SLOP
) {
759 entry
= gd
->gd_vme_base
;
760 KKASSERT(entry
!= NULL
);
761 gd
->gd_vme_base
= entry
->next
;
764 zfree(mapentzone
, entry
);
771 * Reserve map entry structures for use in kernel_map itself. These
772 * entries have *ALREADY* been reserved on a per-cpu basis when the map
773 * was inited. This function is used by zalloc() to avoid a recursion
774 * when zalloc() itself needs to allocate additional kernel memory.
776 * This function works like the normal reserve but does not load the
777 * vm_map_entry cache (because that would result in an infinite
778 * recursion). Note that gd_vme_avail may go negative. This is expected.
780 * Any caller of this function must be sure to renormalize after
781 * potentially eating entries to ensure that the reserve supply
787 vm_map_entry_kreserve(int count
)
789 struct globaldata
*gd
= mycpu
;
792 gd
->gd_vme_avail
-= count
;
794 KASSERT(gd
->gd_vme_base
!= NULL
,
795 ("no reserved entries left, gd_vme_avail = %d",
801 * Release previously reserved map entries for kernel_map. We do not
802 * attempt to clean up like the normal release function as this would
803 * cause an unnecessary (but probably not fatal) deep procedure call.
808 vm_map_entry_krelease(int count
)
810 struct globaldata
*gd
= mycpu
;
813 gd
->gd_vme_avail
+= count
;
818 * Allocates a VM map entry for insertion. No entry fields are filled in.
820 * The entries should have previously been reserved. The reservation count
821 * is tracked in (*countp).
825 static vm_map_entry_t
826 vm_map_entry_create(vm_map_t map
, int *countp
)
828 struct globaldata
*gd
= mycpu
;
829 vm_map_entry_t entry
;
831 KKASSERT(*countp
> 0);
834 entry
= gd
->gd_vme_base
;
835 KASSERT(entry
!= NULL
, ("gd_vme_base NULL! count %d", *countp
));
836 gd
->gd_vme_base
= entry
->next
;
843 * Dispose of a vm_map_entry that is no longer being referenced.
848 vm_map_entry_dispose(vm_map_t map
, vm_map_entry_t entry
, int *countp
)
850 struct globaldata
*gd
= mycpu
;
852 KKASSERT(map
->hint
!= entry
);
853 KKASSERT(map
->first_free
!= entry
);
857 entry
->next
= gd
->gd_vme_base
;
858 gd
->gd_vme_base
= entry
;
864 * Insert/remove entries from maps.
866 * The related map must be exclusively locked.
867 * The caller must hold map->token
868 * No other requirements.
871 vm_map_entry_link(vm_map_t map
,
872 vm_map_entry_t after_where
,
873 vm_map_entry_t entry
)
875 ASSERT_VM_MAP_LOCKED(map
);
878 entry
->prev
= after_where
;
879 entry
->next
= after_where
->next
;
880 entry
->next
->prev
= entry
;
881 after_where
->next
= entry
;
882 if (vm_map_rb_tree_RB_INSERT(&map
->rb_root
, entry
))
883 panic("vm_map_entry_link: dup addr map %p ent %p", map
, entry
);
887 vm_map_entry_unlink(vm_map_t map
,
888 vm_map_entry_t entry
)
893 ASSERT_VM_MAP_LOCKED(map
);
895 if (entry
->eflags
& MAP_ENTRY_IN_TRANSITION
) {
896 panic("vm_map_entry_unlink: attempt to mess with "
897 "locked entry! %p", entry
);
903 vm_map_rb_tree_RB_REMOVE(&map
->rb_root
, entry
);
908 * Finds the map entry containing (or immediately preceding) the specified
909 * address in the given map. The entry is returned in (*entry).
911 * The boolean result indicates whether the address is actually contained
914 * The related map must be locked.
915 * No other requirements.
918 vm_map_lookup_entry(vm_map_t map
, vm_offset_t address
, vm_map_entry_t
*entry
)
923 ASSERT_VM_MAP_LOCKED(map
);
926 * XXX TEMPORARILY DISABLED. For some reason our attempt to revive
927 * the hint code with the red-black lookup meets with system crashes
928 * and lockups. We do not yet know why.
930 * It is possible that the problem is related to the setting
931 * of the hint during map_entry deletion, in the code specified
932 * at the GGG comment later on in this file.
934 * YYY More likely it's because this function can be called with
935 * a shared lock on the map, resulting in map->hint updates possibly
936 * racing. Fixed now but untested.
939 * Quickly check the cached hint, there's a good chance of a match.
943 if (tmp
!= &map
->header
) {
944 if (address
>= tmp
->start
&& address
< tmp
->end
) {
952 * Locate the record from the top of the tree. 'last' tracks the
953 * closest prior record and is returned if no match is found, which
954 * in binary tree terms means tracking the most recent right-branch
955 * taken. If there is no prior record, &map->header is returned.
958 tmp
= RB_ROOT(&map
->rb_root
);
961 if (address
>= tmp
->start
) {
962 if (address
< tmp
->end
) {
968 tmp
= RB_RIGHT(tmp
, rb_entry
);
970 tmp
= RB_LEFT(tmp
, rb_entry
);
978 * Inserts the given whole VM object into the target map at the specified
979 * address range. The object's size should match that of the address range.
981 * The map must be exclusively locked.
982 * The object must be held.
983 * The caller must have reserved sufficient vm_map_entry structures.
985 * If object is non-NULL, ref count must be bumped by caller prior to
986 * making call to account for the new entry.
989 vm_map_insert(vm_map_t map
, int *countp
, void *map_object
, void *map_aux
,
990 vm_ooffset_t offset
, vm_offset_t start
, vm_offset_t end
,
991 vm_maptype_t maptype
, vm_subsys_t id
,
992 vm_prot_t prot
, vm_prot_t max
, int cow
)
994 vm_map_entry_t new_entry
;
995 vm_map_entry_t prev_entry
;
996 vm_map_entry_t temp_entry
;
997 vm_eflags_t protoeflags
;
1001 if (maptype
== VM_MAPTYPE_UKSMAP
)
1004 object
= map_object
;
1006 ASSERT_VM_MAP_LOCKED(map
);
1008 ASSERT_LWKT_TOKEN_HELD(vm_object_token(object
));
1011 * Check that the start and end points are not bogus.
1013 if ((start
< map
->min_offset
) || (end
> map
->max_offset
) ||
1015 return (KERN_INVALID_ADDRESS
);
1018 * Find the entry prior to the proposed starting address; if it's part
1019 * of an existing entry, this range is bogus.
1021 if (vm_map_lookup_entry(map
, start
, &temp_entry
))
1022 return (KERN_NO_SPACE
);
1024 prev_entry
= temp_entry
;
1027 * Assert that the next entry doesn't overlap the end point.
1030 if ((prev_entry
->next
!= &map
->header
) &&
1031 (prev_entry
->next
->start
< end
))
1032 return (KERN_NO_SPACE
);
1036 if (cow
& MAP_COPY_ON_WRITE
)
1037 protoeflags
|= MAP_ENTRY_COW
|MAP_ENTRY_NEEDS_COPY
;
1039 if (cow
& MAP_NOFAULT
) {
1040 protoeflags
|= MAP_ENTRY_NOFAULT
;
1042 KASSERT(object
== NULL
,
1043 ("vm_map_insert: paradoxical MAP_NOFAULT request"));
1045 if (cow
& MAP_DISABLE_SYNCER
)
1046 protoeflags
|= MAP_ENTRY_NOSYNC
;
1047 if (cow
& MAP_DISABLE_COREDUMP
)
1048 protoeflags
|= MAP_ENTRY_NOCOREDUMP
;
1049 if (cow
& MAP_IS_STACK
)
1050 protoeflags
|= MAP_ENTRY_STACK
;
1051 if (cow
& MAP_IS_KSTACK
)
1052 protoeflags
|= MAP_ENTRY_KSTACK
;
1054 lwkt_gettoken(&map
->token
);
1058 * When object is non-NULL, it could be shared with another
1059 * process. We have to set or clear OBJ_ONEMAPPING
1062 * NOTE: This flag is only applicable to DEFAULT and SWAP
1063 * objects and will already be clear in other types
1064 * of objects, so a shared object lock is ok for
1067 if ((object
->ref_count
> 1) || (object
->shadow_count
!= 0)) {
1068 vm_object_clear_flag(object
, OBJ_ONEMAPPING
);
1071 else if ((prev_entry
!= &map
->header
) &&
1072 (prev_entry
->eflags
== protoeflags
) &&
1073 (prev_entry
->end
== start
) &&
1074 (prev_entry
->wired_count
== 0) &&
1075 (prev_entry
->id
== id
) &&
1076 prev_entry
->maptype
== maptype
&&
1077 maptype
== VM_MAPTYPE_NORMAL
&&
1078 ((prev_entry
->object
.vm_object
== NULL
) ||
1079 vm_object_coalesce(prev_entry
->object
.vm_object
,
1080 OFF_TO_IDX(prev_entry
->offset
),
1081 (vm_size_t
)(prev_entry
->end
- prev_entry
->start
),
1082 (vm_size_t
)(end
- prev_entry
->end
)))) {
1084 * We were able to extend the object. Determine if we
1085 * can extend the previous map entry to include the
1086 * new range as well.
1088 if ((prev_entry
->inheritance
== VM_INHERIT_DEFAULT
) &&
1089 (prev_entry
->protection
== prot
) &&
1090 (prev_entry
->max_protection
== max
)) {
1091 map
->size
+= (end
- prev_entry
->end
);
1092 prev_entry
->end
= end
;
1093 vm_map_simplify_entry(map
, prev_entry
, countp
);
1094 lwkt_reltoken(&map
->token
);
1095 return (KERN_SUCCESS
);
1099 * If we can extend the object but cannot extend the
1100 * map entry, we have to create a new map entry. We
1101 * must bump the ref count on the extended object to
1102 * account for it. object may be NULL.
1104 * XXX if object is NULL should we set offset to 0 here ?
1106 object
= prev_entry
->object
.vm_object
;
1107 offset
= prev_entry
->offset
+
1108 (prev_entry
->end
- prev_entry
->start
);
1110 vm_object_hold(object
);
1111 vm_object_chain_wait(object
, 0);
1112 vm_object_reference_locked(object
);
1114 map_object
= object
;
1119 * NOTE: if conditionals fail, object can be NULL here. This occurs
1120 * in things like the buffer map where we manage kva but do not manage
1125 * Create a new entry
1128 new_entry
= vm_map_entry_create(map
, countp
);
1129 new_entry
->start
= start
;
1130 new_entry
->end
= end
;
1133 new_entry
->maptype
= maptype
;
1134 new_entry
->eflags
= protoeflags
;
1135 new_entry
->object
.map_object
= map_object
;
1136 new_entry
->aux
.master_pde
= 0; /* in case size is different */
1137 new_entry
->aux
.map_aux
= map_aux
;
1138 new_entry
->offset
= offset
;
1140 new_entry
->inheritance
= VM_INHERIT_DEFAULT
;
1141 new_entry
->protection
= prot
;
1142 new_entry
->max_protection
= max
;
1143 new_entry
->wired_count
= 0;
1146 * Insert the new entry into the list
1149 vm_map_entry_link(map
, prev_entry
, new_entry
);
1150 map
->size
+= new_entry
->end
- new_entry
->start
;
1153 * Update the free space hint. Entries cannot overlap.
1154 * An exact comparison is needed to avoid matching
1155 * against the map->header.
1157 if ((map
->first_free
== prev_entry
) &&
1158 (prev_entry
->end
== new_entry
->start
)) {
1159 map
->first_free
= new_entry
;
1164 * Temporarily removed to avoid MAP_STACK panic, due to
1165 * MAP_STACK being a huge hack. Will be added back in
1166 * when MAP_STACK (and the user stack mapping) is fixed.
1169 * It may be possible to simplify the entry
1171 vm_map_simplify_entry(map
, new_entry
, countp
);
1175 * Try to pre-populate the page table. Mappings governed by virtual
1176 * page tables cannot be prepopulated without a lot of work, so
1179 if ((cow
& (MAP_PREFAULT
|MAP_PREFAULT_PARTIAL
)) &&
1180 maptype
!= VM_MAPTYPE_VPAGETABLE
&&
1181 maptype
!= VM_MAPTYPE_UKSMAP
) {
1183 if (vm_map_relock_enable
&& (cow
& MAP_PREFAULT_RELOCK
)) {
1185 vm_object_lock_swap();
1186 vm_object_drop(object
);
1188 pmap_object_init_pt(map
->pmap
, start
, prot
,
1189 object
, OFF_TO_IDX(offset
), end
- start
,
1190 cow
& MAP_PREFAULT_PARTIAL
);
1192 vm_object_hold(object
);
1193 vm_object_lock_swap();
1197 vm_object_drop(object
);
1199 lwkt_reltoken(&map
->token
);
1200 return (KERN_SUCCESS
);
1204 * Find sufficient space for `length' bytes in the given map, starting at
1205 * `start'. Returns 0 on success, 1 on no space.
1207 * This function will returned an arbitrarily aligned pointer. If no
1208 * particular alignment is required you should pass align as 1. Note that
1209 * the map may return PAGE_SIZE aligned pointers if all the lengths used in
1210 * the map are a multiple of PAGE_SIZE, even if you pass a smaller align
1213 * 'align' should be a power of 2 but is not required to be.
1215 * The map must be exclusively locked.
1216 * No other requirements.
1219 vm_map_findspace(vm_map_t map
, vm_offset_t start
, vm_size_t length
,
1220 vm_size_t align
, int flags
, vm_offset_t
*addr
)
1222 vm_map_entry_t entry
, next
;
1224 vm_offset_t align_mask
;
1226 if (start
< map
->min_offset
)
1227 start
= map
->min_offset
;
1228 if (start
> map
->max_offset
)
1232 * If the alignment is not a power of 2 we will have to use
1233 * a mod/division, set align_mask to a special value.
1235 if ((align
| (align
- 1)) + 1 != (align
<< 1))
1236 align_mask
= (vm_offset_t
)-1;
1238 align_mask
= align
- 1;
1241 * Look for the first possible address; if there's already something
1242 * at this address, we have to start after it.
1244 if (start
== map
->min_offset
) {
1245 if ((entry
= map
->first_free
) != &map
->header
)
1250 if (vm_map_lookup_entry(map
, start
, &tmp
))
1256 * Look through the rest of the map, trying to fit a new region in the
1257 * gap between existing regions, or after the very last region.
1259 for (;; start
= (entry
= next
)->end
) {
1261 * Adjust the proposed start by the requested alignment,
1262 * be sure that we didn't wrap the address.
1264 if (align_mask
== (vm_offset_t
)-1)
1265 end
= roundup(start
, align
);
1267 end
= (start
+ align_mask
) & ~align_mask
;
1272 * Find the end of the proposed new region. Be sure we didn't
1273 * go beyond the end of the map, or wrap around the address.
1274 * Then check to see if this is the last entry or if the
1275 * proposed end fits in the gap between this and the next
1278 end
= start
+ length
;
1279 if (end
> map
->max_offset
|| end
< start
)
1284 * If the next entry's start address is beyond the desired
1285 * end address we may have found a good entry.
1287 * If the next entry is a stack mapping we do not map into
1288 * the stack's reserved space.
1290 * XXX continue to allow mapping into the stack's reserved
1291 * space if doing a MAP_STACK mapping inside a MAP_STACK
1292 * mapping, for backwards compatibility. But the caller
1293 * really should use MAP_STACK | MAP_TRYFIXED if they
1296 if (next
== &map
->header
)
1298 if (next
->start
>= end
) {
1299 if ((next
->eflags
& MAP_ENTRY_STACK
) == 0)
1301 if (flags
& MAP_STACK
)
1303 if (next
->start
- next
->aux
.avail_ssize
>= end
)
1310 * Grow the kernel_map if necessary. pmap_growkernel() will panic
1311 * if it fails. The kernel_map is locked and nothing can steal
1312 * our address space if pmap_growkernel() blocks.
1314 * NOTE: This may be unconditionally called for kldload areas on
1315 * x86_64 because these do not bump kernel_vm_end (which would
1316 * fill 128G worth of page tables!). Therefore we must not
1319 if (map
== &kernel_map
) {
1322 kstop
= round_page(start
+ length
);
1323 if (kstop
> kernel_vm_end
)
1324 pmap_growkernel(start
, kstop
);
1331 * vm_map_find finds an unallocated region in the target address map with
1332 * the given length and allocates it. The search is defined to be first-fit
1333 * from the specified address; the region found is returned in the same
1336 * If object is non-NULL, ref count must be bumped by caller
1337 * prior to making call to account for the new entry.
1339 * No requirements. This function will lock the map temporarily.
1342 vm_map_find(vm_map_t map
, void *map_object
, void *map_aux
,
1343 vm_ooffset_t offset
, vm_offset_t
*addr
,
1344 vm_size_t length
, vm_size_t align
, boolean_t fitit
,
1345 vm_maptype_t maptype
, vm_subsys_t id
,
1346 vm_prot_t prot
, vm_prot_t max
, int cow
)
1353 if (maptype
== VM_MAPTYPE_UKSMAP
)
1356 object
= map_object
;
1360 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
1363 vm_object_hold_shared(object
);
1365 if (vm_map_findspace(map
, start
, length
, align
, 0, addr
)) {
1367 vm_object_drop(object
);
1369 vm_map_entry_release(count
);
1370 return (KERN_NO_SPACE
);
1374 result
= vm_map_insert(map
, &count
, map_object
, map_aux
,
1375 offset
, start
, start
+ length
,
1376 maptype
, id
, prot
, max
, cow
);
1378 vm_object_drop(object
);
1380 vm_map_entry_release(count
);
1386 * Simplify the given map entry by merging with either neighbor. This
1387 * routine also has the ability to merge with both neighbors.
1389 * This routine guarentees that the passed entry remains valid (though
1390 * possibly extended). When merging, this routine may delete one or
1391 * both neighbors. No action is taken on entries which have their
1392 * in-transition flag set.
1394 * The map must be exclusively locked.
1397 vm_map_simplify_entry(vm_map_t map
, vm_map_entry_t entry
, int *countp
)
1399 vm_map_entry_t next
, prev
;
1400 vm_size_t prevsize
, esize
;
1402 if (entry
->eflags
& MAP_ENTRY_IN_TRANSITION
) {
1403 ++mycpu
->gd_cnt
.v_intrans_coll
;
1407 if (entry
->maptype
== VM_MAPTYPE_SUBMAP
)
1409 if (entry
->maptype
== VM_MAPTYPE_UKSMAP
)
1413 if (prev
!= &map
->header
) {
1414 prevsize
= prev
->end
- prev
->start
;
1415 if ( (prev
->end
== entry
->start
) &&
1416 (prev
->maptype
== entry
->maptype
) &&
1417 (prev
->object
.vm_object
== entry
->object
.vm_object
) &&
1418 (!prev
->object
.vm_object
||
1419 (prev
->offset
+ prevsize
== entry
->offset
)) &&
1420 (prev
->eflags
== entry
->eflags
) &&
1421 (prev
->protection
== entry
->protection
) &&
1422 (prev
->max_protection
== entry
->max_protection
) &&
1423 (prev
->inheritance
== entry
->inheritance
) &&
1424 (prev
->id
== entry
->id
) &&
1425 (prev
->wired_count
== entry
->wired_count
)) {
1426 if (map
->first_free
== prev
)
1427 map
->first_free
= entry
;
1428 if (map
->hint
== prev
)
1430 vm_map_entry_unlink(map
, prev
);
1431 entry
->start
= prev
->start
;
1432 entry
->offset
= prev
->offset
;
1433 if (prev
->object
.vm_object
)
1434 vm_object_deallocate(prev
->object
.vm_object
);
1435 vm_map_entry_dispose(map
, prev
, countp
);
1440 if (next
!= &map
->header
) {
1441 esize
= entry
->end
- entry
->start
;
1442 if ((entry
->end
== next
->start
) &&
1443 (next
->maptype
== entry
->maptype
) &&
1444 (next
->object
.vm_object
== entry
->object
.vm_object
) &&
1445 (!entry
->object
.vm_object
||
1446 (entry
->offset
+ esize
== next
->offset
)) &&
1447 (next
->eflags
== entry
->eflags
) &&
1448 (next
->protection
== entry
->protection
) &&
1449 (next
->max_protection
== entry
->max_protection
) &&
1450 (next
->inheritance
== entry
->inheritance
) &&
1451 (next
->id
== entry
->id
) &&
1452 (next
->wired_count
== entry
->wired_count
)) {
1453 if (map
->first_free
== next
)
1454 map
->first_free
= entry
;
1455 if (map
->hint
== next
)
1457 vm_map_entry_unlink(map
, next
);
1458 entry
->end
= next
->end
;
1459 if (next
->object
.vm_object
)
1460 vm_object_deallocate(next
->object
.vm_object
);
1461 vm_map_entry_dispose(map
, next
, countp
);
1467 * Asserts that the given entry begins at or after the specified address.
1468 * If necessary, it splits the entry into two.
1470 #define vm_map_clip_start(map, entry, startaddr, countp) \
1472 if (startaddr > entry->start) \
1473 _vm_map_clip_start(map, entry, startaddr, countp); \
1477 * This routine is called only when it is known that the entry must be split.
1479 * The map must be exclusively locked.
1482 _vm_map_clip_start(vm_map_t map
, vm_map_entry_t entry
, vm_offset_t start
,
1485 vm_map_entry_t new_entry
;
1488 * Split off the front portion -- note that we must insert the new
1489 * entry BEFORE this one, so that this entry has the specified
1493 vm_map_simplify_entry(map
, entry
, countp
);
1496 * If there is no object backing this entry, we might as well create
1497 * one now. If we defer it, an object can get created after the map
1498 * is clipped, and individual objects will be created for the split-up
1499 * map. This is a bit of a hack, but is also about the best place to
1500 * put this improvement.
1502 if (entry
->object
.vm_object
== NULL
&& !map
->system_map
) {
1503 vm_map_entry_allocate_object(entry
);
1506 new_entry
= vm_map_entry_create(map
, countp
);
1507 *new_entry
= *entry
;
1509 new_entry
->end
= start
;
1510 entry
->offset
+= (start
- entry
->start
);
1511 entry
->start
= start
;
1513 vm_map_entry_link(map
, entry
->prev
, new_entry
);
1515 switch(entry
->maptype
) {
1516 case VM_MAPTYPE_NORMAL
:
1517 case VM_MAPTYPE_VPAGETABLE
:
1518 if (new_entry
->object
.vm_object
) {
1519 vm_object_hold(new_entry
->object
.vm_object
);
1520 vm_object_chain_wait(new_entry
->object
.vm_object
, 0);
1521 vm_object_reference_locked(new_entry
->object
.vm_object
);
1522 vm_object_drop(new_entry
->object
.vm_object
);
1531 * Asserts that the given entry ends at or before the specified address.
1532 * If necessary, it splits the entry into two.
1534 * The map must be exclusively locked.
1536 #define vm_map_clip_end(map, entry, endaddr, countp) \
1538 if (endaddr < entry->end) \
1539 _vm_map_clip_end(map, entry, endaddr, countp); \
1543 * This routine is called only when it is known that the entry must be split.
1545 * The map must be exclusively locked.
1548 _vm_map_clip_end(vm_map_t map
, vm_map_entry_t entry
, vm_offset_t end
,
1551 vm_map_entry_t new_entry
;
1554 * If there is no object backing this entry, we might as well create
1555 * one now. If we defer it, an object can get created after the map
1556 * is clipped, and individual objects will be created for the split-up
1557 * map. This is a bit of a hack, but is also about the best place to
1558 * put this improvement.
1561 if (entry
->object
.vm_object
== NULL
&& !map
->system_map
) {
1562 vm_map_entry_allocate_object(entry
);
1566 * Create a new entry and insert it AFTER the specified entry
1569 new_entry
= vm_map_entry_create(map
, countp
);
1570 *new_entry
= *entry
;
1572 new_entry
->start
= entry
->end
= end
;
1573 new_entry
->offset
+= (end
- entry
->start
);
1575 vm_map_entry_link(map
, entry
, new_entry
);
1577 switch(entry
->maptype
) {
1578 case VM_MAPTYPE_NORMAL
:
1579 case VM_MAPTYPE_VPAGETABLE
:
1580 if (new_entry
->object
.vm_object
) {
1581 vm_object_hold(new_entry
->object
.vm_object
);
1582 vm_object_chain_wait(new_entry
->object
.vm_object
, 0);
1583 vm_object_reference_locked(new_entry
->object
.vm_object
);
1584 vm_object_drop(new_entry
->object
.vm_object
);
1593 * Asserts that the starting and ending region addresses fall within the
1594 * valid range for the map.
1596 #define VM_MAP_RANGE_CHECK(map, start, end) \
1598 if (start < vm_map_min(map)) \
1599 start = vm_map_min(map); \
1600 if (end > vm_map_max(map)) \
1601 end = vm_map_max(map); \
1607 * Used to block when an in-transition collison occurs. The map
1608 * is unlocked for the sleep and relocked before the return.
1611 vm_map_transition_wait(vm_map_t map
)
1613 tsleep_interlock(map
, 0);
1615 tsleep(map
, PINTERLOCKED
, "vment", 0);
1620 * When we do blocking operations with the map lock held it is
1621 * possible that a clip might have occured on our in-transit entry,
1622 * requiring an adjustment to the entry in our loop. These macros
1623 * help the pageable and clip_range code deal with the case. The
1624 * conditional costs virtually nothing if no clipping has occured.
1627 #define CLIP_CHECK_BACK(entry, save_start) \
1629 while (entry->start != save_start) { \
1630 entry = entry->prev; \
1631 KASSERT(entry != &map->header, ("bad entry clip")); \
1635 #define CLIP_CHECK_FWD(entry, save_end) \
1637 while (entry->end != save_end) { \
1638 entry = entry->next; \
1639 KASSERT(entry != &map->header, ("bad entry clip")); \
1645 * Clip the specified range and return the base entry. The
1646 * range may cover several entries starting at the returned base
1647 * and the first and last entry in the covering sequence will be
1648 * properly clipped to the requested start and end address.
1650 * If no holes are allowed you should pass the MAP_CLIP_NO_HOLES
1653 * The MAP_ENTRY_IN_TRANSITION flag will be set for the entries
1654 * covered by the requested range.
1656 * The map must be exclusively locked on entry and will remain locked
1657 * on return. If no range exists or the range contains holes and you
1658 * specified that no holes were allowed, NULL will be returned. This
1659 * routine may temporarily unlock the map in order avoid a deadlock when
1664 vm_map_clip_range(vm_map_t map
, vm_offset_t start
, vm_offset_t end
,
1665 int *countp
, int flags
)
1667 vm_map_entry_t start_entry
;
1668 vm_map_entry_t entry
;
1671 * Locate the entry and effect initial clipping. The in-transition
1672 * case does not occur very often so do not try to optimize it.
1675 if (vm_map_lookup_entry(map
, start
, &start_entry
) == FALSE
)
1677 entry
= start_entry
;
1678 if (entry
->eflags
& MAP_ENTRY_IN_TRANSITION
) {
1679 entry
->eflags
|= MAP_ENTRY_NEEDS_WAKEUP
;
1680 ++mycpu
->gd_cnt
.v_intrans_coll
;
1681 ++mycpu
->gd_cnt
.v_intrans_wait
;
1682 vm_map_transition_wait(map
);
1684 * entry and/or start_entry may have been clipped while
1685 * we slept, or may have gone away entirely. We have
1686 * to restart from the lookup.
1692 * Since we hold an exclusive map lock we do not have to restart
1693 * after clipping, even though clipping may block in zalloc.
1695 vm_map_clip_start(map
, entry
, start
, countp
);
1696 vm_map_clip_end(map
, entry
, end
, countp
);
1697 entry
->eflags
|= MAP_ENTRY_IN_TRANSITION
;
1700 * Scan entries covered by the range. When working on the next
1701 * entry a restart need only re-loop on the current entry which
1702 * we have already locked, since 'next' may have changed. Also,
1703 * even though entry is safe, it may have been clipped so we
1704 * have to iterate forwards through the clip after sleeping.
1706 while (entry
->next
!= &map
->header
&& entry
->next
->start
< end
) {
1707 vm_map_entry_t next
= entry
->next
;
1709 if (flags
& MAP_CLIP_NO_HOLES
) {
1710 if (next
->start
> entry
->end
) {
1711 vm_map_unclip_range(map
, start_entry
,
1712 start
, entry
->end
, countp
, flags
);
1717 if (next
->eflags
& MAP_ENTRY_IN_TRANSITION
) {
1718 vm_offset_t save_end
= entry
->end
;
1719 next
->eflags
|= MAP_ENTRY_NEEDS_WAKEUP
;
1720 ++mycpu
->gd_cnt
.v_intrans_coll
;
1721 ++mycpu
->gd_cnt
.v_intrans_wait
;
1722 vm_map_transition_wait(map
);
1725 * clips might have occured while we blocked.
1727 CLIP_CHECK_FWD(entry
, save_end
);
1728 CLIP_CHECK_BACK(start_entry
, start
);
1732 * No restart necessary even though clip_end may block, we
1733 * are holding the map lock.
1735 vm_map_clip_end(map
, next
, end
, countp
);
1736 next
->eflags
|= MAP_ENTRY_IN_TRANSITION
;
1739 if (flags
& MAP_CLIP_NO_HOLES
) {
1740 if (entry
->end
!= end
) {
1741 vm_map_unclip_range(map
, start_entry
,
1742 start
, entry
->end
, countp
, flags
);
1746 return(start_entry
);
1750 * Undo the effect of vm_map_clip_range(). You should pass the same
1751 * flags and the same range that you passed to vm_map_clip_range().
1752 * This code will clear the in-transition flag on the entries and
1753 * wake up anyone waiting. This code will also simplify the sequence
1754 * and attempt to merge it with entries before and after the sequence.
1756 * The map must be locked on entry and will remain locked on return.
1758 * Note that you should also pass the start_entry returned by
1759 * vm_map_clip_range(). However, if you block between the two calls
1760 * with the map unlocked please be aware that the start_entry may
1761 * have been clipped and you may need to scan it backwards to find
1762 * the entry corresponding with the original start address. You are
1763 * responsible for this, vm_map_unclip_range() expects the correct
1764 * start_entry to be passed to it and will KASSERT otherwise.
1768 vm_map_unclip_range(vm_map_t map
, vm_map_entry_t start_entry
,
1769 vm_offset_t start
, vm_offset_t end
,
1770 int *countp
, int flags
)
1772 vm_map_entry_t entry
;
1774 entry
= start_entry
;
1776 KASSERT(entry
->start
== start
, ("unclip_range: illegal base entry"));
1777 while (entry
!= &map
->header
&& entry
->start
< end
) {
1778 KASSERT(entry
->eflags
& MAP_ENTRY_IN_TRANSITION
,
1779 ("in-transition flag not set during unclip on: %p",
1781 KASSERT(entry
->end
<= end
,
1782 ("unclip_range: tail wasn't clipped"));
1783 entry
->eflags
&= ~MAP_ENTRY_IN_TRANSITION
;
1784 if (entry
->eflags
& MAP_ENTRY_NEEDS_WAKEUP
) {
1785 entry
->eflags
&= ~MAP_ENTRY_NEEDS_WAKEUP
;
1788 entry
= entry
->next
;
1792 * Simplification does not block so there is no restart case.
1794 entry
= start_entry
;
1795 while (entry
!= &map
->header
&& entry
->start
< end
) {
1796 vm_map_simplify_entry(map
, entry
, countp
);
1797 entry
= entry
->next
;
1802 * Mark the given range as handled by a subordinate map.
1804 * This range must have been created with vm_map_find(), and no other
1805 * operations may have been performed on this range prior to calling
1808 * Submappings cannot be removed.
1813 vm_map_submap(vm_map_t map
, vm_offset_t start
, vm_offset_t end
, vm_map_t submap
)
1815 vm_map_entry_t entry
;
1816 int result
= KERN_INVALID_ARGUMENT
;
1819 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
1822 VM_MAP_RANGE_CHECK(map
, start
, end
);
1824 if (vm_map_lookup_entry(map
, start
, &entry
)) {
1825 vm_map_clip_start(map
, entry
, start
, &count
);
1827 entry
= entry
->next
;
1830 vm_map_clip_end(map
, entry
, end
, &count
);
1832 if ((entry
->start
== start
) && (entry
->end
== end
) &&
1833 ((entry
->eflags
& MAP_ENTRY_COW
) == 0) &&
1834 (entry
->object
.vm_object
== NULL
)) {
1835 entry
->object
.sub_map
= submap
;
1836 entry
->maptype
= VM_MAPTYPE_SUBMAP
;
1837 result
= KERN_SUCCESS
;
1840 vm_map_entry_release(count
);
1846 * Sets the protection of the specified address region in the target map.
1847 * If "set_max" is specified, the maximum protection is to be set;
1848 * otherwise, only the current protection is affected.
1850 * The protection is not applicable to submaps, but is applicable to normal
1851 * maps and maps governed by virtual page tables. For example, when operating
1852 * on a virtual page table our protection basically controls how COW occurs
1853 * on the backing object, whereas the virtual page table abstraction itself
1854 * is an abstraction for userland.
1859 vm_map_protect(vm_map_t map
, vm_offset_t start
, vm_offset_t end
,
1860 vm_prot_t new_prot
, boolean_t set_max
)
1862 vm_map_entry_t current
;
1863 vm_map_entry_t entry
;
1866 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
1869 VM_MAP_RANGE_CHECK(map
, start
, end
);
1871 if (vm_map_lookup_entry(map
, start
, &entry
)) {
1872 vm_map_clip_start(map
, entry
, start
, &count
);
1874 entry
= entry
->next
;
1878 * Make a first pass to check for protection violations.
1881 while ((current
!= &map
->header
) && (current
->start
< end
)) {
1882 if (current
->maptype
== VM_MAPTYPE_SUBMAP
) {
1884 vm_map_entry_release(count
);
1885 return (KERN_INVALID_ARGUMENT
);
1887 if ((new_prot
& current
->max_protection
) != new_prot
) {
1889 vm_map_entry_release(count
);
1890 return (KERN_PROTECTION_FAILURE
);
1892 current
= current
->next
;
1896 * Go back and fix up protections. [Note that clipping is not
1897 * necessary the second time.]
1901 while ((current
!= &map
->header
) && (current
->start
< end
)) {
1904 vm_map_clip_end(map
, current
, end
, &count
);
1906 old_prot
= current
->protection
;
1908 current
->max_protection
= new_prot
;
1909 current
->protection
= new_prot
& old_prot
;
1911 current
->protection
= new_prot
;
1915 * Update physical map if necessary. Worry about copy-on-write
1916 * here -- CHECK THIS XXX
1919 if (current
->protection
!= old_prot
) {
1920 #define MASK(entry) (((entry)->eflags & MAP_ENTRY_COW) ? ~VM_PROT_WRITE : \
1923 pmap_protect(map
->pmap
, current
->start
,
1925 current
->protection
& MASK(current
));
1929 vm_map_simplify_entry(map
, current
, &count
);
1931 current
= current
->next
;
1935 vm_map_entry_release(count
);
1936 return (KERN_SUCCESS
);
1940 * This routine traverses a processes map handling the madvise
1941 * system call. Advisories are classified as either those effecting
1942 * the vm_map_entry structure, or those effecting the underlying
1945 * The <value> argument is used for extended madvise calls.
1950 vm_map_madvise(vm_map_t map
, vm_offset_t start
, vm_offset_t end
,
1951 int behav
, off_t value
)
1953 vm_map_entry_t current
, entry
;
1959 * Some madvise calls directly modify the vm_map_entry, in which case
1960 * we need to use an exclusive lock on the map and we need to perform
1961 * various clipping operations. Otherwise we only need a read-lock
1964 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
1968 case MADV_SEQUENTIAL
:
1982 vm_map_lock_read(map
);
1985 vm_map_entry_release(count
);
1990 * Locate starting entry and clip if necessary.
1993 VM_MAP_RANGE_CHECK(map
, start
, end
);
1995 if (vm_map_lookup_entry(map
, start
, &entry
)) {
1997 vm_map_clip_start(map
, entry
, start
, &count
);
1999 entry
= entry
->next
;
2004 * madvise behaviors that are implemented in the vm_map_entry.
2006 * We clip the vm_map_entry so that behavioral changes are
2007 * limited to the specified address range.
2009 for (current
= entry
;
2010 (current
!= &map
->header
) && (current
->start
< end
);
2011 current
= current
->next
2013 if (current
->maptype
== VM_MAPTYPE_SUBMAP
)
2016 vm_map_clip_end(map
, current
, end
, &count
);
2020 vm_map_entry_set_behavior(current
, MAP_ENTRY_BEHAV_NORMAL
);
2022 case MADV_SEQUENTIAL
:
2023 vm_map_entry_set_behavior(current
, MAP_ENTRY_BEHAV_SEQUENTIAL
);
2026 vm_map_entry_set_behavior(current
, MAP_ENTRY_BEHAV_RANDOM
);
2029 current
->eflags
|= MAP_ENTRY_NOSYNC
;
2032 current
->eflags
&= ~MAP_ENTRY_NOSYNC
;
2035 current
->eflags
|= MAP_ENTRY_NOCOREDUMP
;
2038 current
->eflags
&= ~MAP_ENTRY_NOCOREDUMP
;
2042 * Set the page directory page for a map
2043 * governed by a virtual page table. Mark
2044 * the entry as being governed by a virtual
2045 * page table if it is not.
2047 * XXX the page directory page is stored
2048 * in the avail_ssize field if the map_entry.
2050 * XXX the map simplification code does not
2051 * compare this field so weird things may
2052 * happen if you do not apply this function
2053 * to the entire mapping governed by the
2054 * virtual page table.
2056 if (current
->maptype
!= VM_MAPTYPE_VPAGETABLE
) {
2060 current
->aux
.master_pde
= value
;
2061 pmap_remove(map
->pmap
,
2062 current
->start
, current
->end
);
2066 * Invalidate the related pmap entries, used
2067 * to flush portions of the real kernel's
2068 * pmap when the caller has removed or
2069 * modified existing mappings in a virtual
2072 * (exclusive locked map version does not
2073 * need the range interlock).
2075 pmap_remove(map
->pmap
,
2076 current
->start
, current
->end
);
2082 vm_map_simplify_entry(map
, current
, &count
);
2090 * madvise behaviors that are implemented in the underlying
2093 * Since we don't clip the vm_map_entry, we have to clip
2094 * the vm_object pindex and count.
2096 * NOTE! These functions are only supported on normal maps,
2097 * except MADV_INVAL which is also supported on
2098 * virtual page tables.
2100 for (current
= entry
;
2101 (current
!= &map
->header
) && (current
->start
< end
);
2102 current
= current
->next
2104 vm_offset_t useStart
;
2106 if (current
->maptype
!= VM_MAPTYPE_NORMAL
&&
2107 (current
->maptype
!= VM_MAPTYPE_VPAGETABLE
||
2108 behav
!= MADV_INVAL
)) {
2112 pindex
= OFF_TO_IDX(current
->offset
);
2113 delta
= atop(current
->end
- current
->start
);
2114 useStart
= current
->start
;
2116 if (current
->start
< start
) {
2117 pindex
+= atop(start
- current
->start
);
2118 delta
-= atop(start
- current
->start
);
2121 if (current
->end
> end
)
2122 delta
-= atop(current
->end
- end
);
2124 if ((vm_spindex_t
)delta
<= 0)
2127 if (behav
== MADV_INVAL
) {
2129 * Invalidate the related pmap entries, used
2130 * to flush portions of the real kernel's
2131 * pmap when the caller has removed or
2132 * modified existing mappings in a virtual
2135 * (shared locked map version needs the
2136 * interlock, see vm_fault()).
2138 struct vm_map_ilock ilock
;
2140 KASSERT(useStart
>= VM_MIN_USER_ADDRESS
&&
2141 useStart
+ ptoa(delta
) <=
2142 VM_MAX_USER_ADDRESS
,
2143 ("Bad range %016jx-%016jx (%016jx)",
2144 useStart
, useStart
+ ptoa(delta
),
2146 vm_map_interlock(map
, &ilock
,
2148 useStart
+ ptoa(delta
));
2149 pmap_remove(map
->pmap
,
2151 useStart
+ ptoa(delta
));
2152 vm_map_deinterlock(map
, &ilock
);
2154 vm_object_madvise(current
->object
.vm_object
,
2155 pindex
, delta
, behav
);
2159 * Try to populate the page table. Mappings governed
2160 * by virtual page tables cannot be pre-populated
2161 * without a lot of work so don't try.
2163 if (behav
== MADV_WILLNEED
&&
2164 current
->maptype
!= VM_MAPTYPE_VPAGETABLE
) {
2165 pmap_object_init_pt(
2168 current
->protection
,
2169 current
->object
.vm_object
,
2171 (count
<< PAGE_SHIFT
),
2172 MAP_PREFAULT_MADVISE
2176 vm_map_unlock_read(map
);
2178 vm_map_entry_release(count
);
2184 * Sets the inheritance of the specified address range in the target map.
2185 * Inheritance affects how the map will be shared with child maps at the
2186 * time of vm_map_fork.
2189 vm_map_inherit(vm_map_t map
, vm_offset_t start
, vm_offset_t end
,
2190 vm_inherit_t new_inheritance
)
2192 vm_map_entry_t entry
;
2193 vm_map_entry_t temp_entry
;
2196 switch (new_inheritance
) {
2197 case VM_INHERIT_NONE
:
2198 case VM_INHERIT_COPY
:
2199 case VM_INHERIT_SHARE
:
2202 return (KERN_INVALID_ARGUMENT
);
2205 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
2208 VM_MAP_RANGE_CHECK(map
, start
, end
);
2210 if (vm_map_lookup_entry(map
, start
, &temp_entry
)) {
2212 vm_map_clip_start(map
, entry
, start
, &count
);
2214 entry
= temp_entry
->next
;
2216 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
2217 vm_map_clip_end(map
, entry
, end
, &count
);
2219 entry
->inheritance
= new_inheritance
;
2221 vm_map_simplify_entry(map
, entry
, &count
);
2223 entry
= entry
->next
;
2226 vm_map_entry_release(count
);
2227 return (KERN_SUCCESS
);
2231 * Implement the semantics of mlock
2234 vm_map_unwire(vm_map_t map
, vm_offset_t start
, vm_offset_t real_end
,
2235 boolean_t new_pageable
)
2237 vm_map_entry_t entry
;
2238 vm_map_entry_t start_entry
;
2240 int rv
= KERN_SUCCESS
;
2243 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
2245 VM_MAP_RANGE_CHECK(map
, start
, real_end
);
2248 start_entry
= vm_map_clip_range(map
, start
, end
, &count
,
2250 if (start_entry
== NULL
) {
2252 vm_map_entry_release(count
);
2253 return (KERN_INVALID_ADDRESS
);
2256 if (new_pageable
== 0) {
2257 entry
= start_entry
;
2258 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
2259 vm_offset_t save_start
;
2260 vm_offset_t save_end
;
2263 * Already user wired or hard wired (trivial cases)
2265 if (entry
->eflags
& MAP_ENTRY_USER_WIRED
) {
2266 entry
= entry
->next
;
2269 if (entry
->wired_count
!= 0) {
2270 entry
->wired_count
++;
2271 entry
->eflags
|= MAP_ENTRY_USER_WIRED
;
2272 entry
= entry
->next
;
2277 * A new wiring requires instantiation of appropriate
2278 * management structures and the faulting in of the
2281 if (entry
->maptype
== VM_MAPTYPE_NORMAL
||
2282 entry
->maptype
== VM_MAPTYPE_VPAGETABLE
) {
2283 int copyflag
= entry
->eflags
&
2284 MAP_ENTRY_NEEDS_COPY
;
2285 if (copyflag
&& ((entry
->protection
&
2286 VM_PROT_WRITE
) != 0)) {
2287 vm_map_entry_shadow(entry
, 0);
2288 } else if (entry
->object
.vm_object
== NULL
&&
2290 vm_map_entry_allocate_object(entry
);
2293 entry
->wired_count
++;
2294 entry
->eflags
|= MAP_ENTRY_USER_WIRED
;
2297 * Now fault in the area. Note that vm_fault_wire()
2298 * may release the map lock temporarily, it will be
2299 * relocked on return. The in-transition
2300 * flag protects the entries.
2302 save_start
= entry
->start
;
2303 save_end
= entry
->end
;
2304 rv
= vm_fault_wire(map
, entry
, TRUE
, 0);
2306 CLIP_CHECK_BACK(entry
, save_start
);
2308 KASSERT(entry
->wired_count
== 1, ("bad wired_count on entry"));
2309 entry
->eflags
&= ~MAP_ENTRY_USER_WIRED
;
2310 entry
->wired_count
= 0;
2311 if (entry
->end
== save_end
)
2313 entry
= entry
->next
;
2314 KASSERT(entry
!= &map
->header
, ("bad entry clip during backout"));
2316 end
= save_start
; /* unwire the rest */
2320 * note that even though the entry might have been
2321 * clipped, the USER_WIRED flag we set prevents
2322 * duplication so we do not have to do a
2325 entry
= entry
->next
;
2329 * If we failed fall through to the unwiring section to
2330 * unwire what we had wired so far. 'end' has already
2337 * start_entry might have been clipped if we unlocked the
2338 * map and blocked. No matter how clipped it has gotten
2339 * there should be a fragment that is on our start boundary.
2341 CLIP_CHECK_BACK(start_entry
, start
);
2345 * Deal with the unwiring case.
2349 * This is the unwiring case. We must first ensure that the
2350 * range to be unwired is really wired down. We know there
2353 entry
= start_entry
;
2354 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
2355 if ((entry
->eflags
& MAP_ENTRY_USER_WIRED
) == 0) {
2356 rv
= KERN_INVALID_ARGUMENT
;
2359 KASSERT(entry
->wired_count
!= 0, ("wired count was 0 with USER_WIRED set! %p", entry
));
2360 entry
= entry
->next
;
2364 * Now decrement the wiring count for each region. If a region
2365 * becomes completely unwired, unwire its physical pages and
2369 * The map entries are processed in a loop, checking to
2370 * make sure the entry is wired and asserting it has a wired
2371 * count. However, another loop was inserted more-or-less in
2372 * the middle of the unwiring path. This loop picks up the
2373 * "entry" loop variable from the first loop without first
2374 * setting it to start_entry. Naturally, the secound loop
2375 * is never entered and the pages backing the entries are
2376 * never unwired. This can lead to a leak of wired pages.
2378 entry
= start_entry
;
2379 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
2380 KASSERT(entry
->eflags
& MAP_ENTRY_USER_WIRED
,
2381 ("expected USER_WIRED on entry %p", entry
));
2382 entry
->eflags
&= ~MAP_ENTRY_USER_WIRED
;
2383 entry
->wired_count
--;
2384 if (entry
->wired_count
== 0)
2385 vm_fault_unwire(map
, entry
);
2386 entry
= entry
->next
;
2390 vm_map_unclip_range(map
, start_entry
, start
, real_end
, &count
,
2394 vm_map_entry_release(count
);
2399 * Sets the pageability of the specified address range in the target map.
2400 * Regions specified as not pageable require locked-down physical
2401 * memory and physical page maps.
2403 * The map must not be locked, but a reference must remain to the map
2404 * throughout the call.
2406 * This function may be called via the zalloc path and must properly
2407 * reserve map entries for kernel_map.
2412 vm_map_wire(vm_map_t map
, vm_offset_t start
, vm_offset_t real_end
, int kmflags
)
2414 vm_map_entry_t entry
;
2415 vm_map_entry_t start_entry
;
2417 int rv
= KERN_SUCCESS
;
2420 if (kmflags
& KM_KRESERVE
)
2421 count
= vm_map_entry_kreserve(MAP_RESERVE_COUNT
);
2423 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
2425 VM_MAP_RANGE_CHECK(map
, start
, real_end
);
2428 start_entry
= vm_map_clip_range(map
, start
, end
, &count
,
2430 if (start_entry
== NULL
) {
2432 rv
= KERN_INVALID_ADDRESS
;
2435 if ((kmflags
& KM_PAGEABLE
) == 0) {
2439 * 1. Holding the write lock, we create any shadow or zero-fill
2440 * objects that need to be created. Then we clip each map
2441 * entry to the region to be wired and increment its wiring
2442 * count. We create objects before clipping the map entries
2443 * to avoid object proliferation.
2445 * 2. We downgrade to a read lock, and call vm_fault_wire to
2446 * fault in the pages for any newly wired area (wired_count is
2449 * Downgrading to a read lock for vm_fault_wire avoids a
2450 * possible deadlock with another process that may have faulted
2451 * on one of the pages to be wired (it would mark the page busy,
2452 * blocking us, then in turn block on the map lock that we
2453 * hold). Because of problems in the recursive lock package,
2454 * we cannot upgrade to a write lock in vm_map_lookup. Thus,
2455 * any actions that require the write lock must be done
2456 * beforehand. Because we keep the read lock on the map, the
2457 * copy-on-write status of the entries we modify here cannot
2460 entry
= start_entry
;
2461 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
2463 * Trivial case if the entry is already wired
2465 if (entry
->wired_count
) {
2466 entry
->wired_count
++;
2467 entry
= entry
->next
;
2472 * The entry is being newly wired, we have to setup
2473 * appropriate management structures. A shadow
2474 * object is required for a copy-on-write region,
2475 * or a normal object for a zero-fill region. We
2476 * do not have to do this for entries that point to sub
2477 * maps because we won't hold the lock on the sub map.
2479 if (entry
->maptype
== VM_MAPTYPE_NORMAL
||
2480 entry
->maptype
== VM_MAPTYPE_VPAGETABLE
) {
2481 int copyflag
= entry
->eflags
&
2482 MAP_ENTRY_NEEDS_COPY
;
2483 if (copyflag
&& ((entry
->protection
&
2484 VM_PROT_WRITE
) != 0)) {
2485 vm_map_entry_shadow(entry
, 0);
2486 } else if (entry
->object
.vm_object
== NULL
&&
2488 vm_map_entry_allocate_object(entry
);
2492 entry
->wired_count
++;
2493 entry
= entry
->next
;
2501 * HACK HACK HACK HACK
2503 * vm_fault_wire() temporarily unlocks the map to avoid
2504 * deadlocks. The in-transition flag from vm_map_clip_range
2505 * call should protect us from changes while the map is
2508 * NOTE: Previously this comment stated that clipping might
2509 * still occur while the entry is unlocked, but from
2510 * what I can tell it actually cannot.
2512 * It is unclear whether the CLIP_CHECK_*() calls
2513 * are still needed but we keep them in anyway.
2515 * HACK HACK HACK HACK
2518 entry
= start_entry
;
2519 while (entry
!= &map
->header
&& entry
->start
< end
) {
2521 * If vm_fault_wire fails for any page we need to undo
2522 * what has been done. We decrement the wiring count
2523 * for those pages which have not yet been wired (now)
2524 * and unwire those that have (later).
2526 vm_offset_t save_start
= entry
->start
;
2527 vm_offset_t save_end
= entry
->end
;
2529 if (entry
->wired_count
== 1)
2530 rv
= vm_fault_wire(map
, entry
, FALSE
, kmflags
);
2532 CLIP_CHECK_BACK(entry
, save_start
);
2534 KASSERT(entry
->wired_count
== 1, ("wired_count changed unexpectedly"));
2535 entry
->wired_count
= 0;
2536 if (entry
->end
== save_end
)
2538 entry
= entry
->next
;
2539 KASSERT(entry
!= &map
->header
, ("bad entry clip during backout"));
2544 CLIP_CHECK_FWD(entry
, save_end
);
2545 entry
= entry
->next
;
2549 * If a failure occured undo everything by falling through
2550 * to the unwiring code. 'end' has already been adjusted
2554 kmflags
|= KM_PAGEABLE
;
2557 * start_entry is still IN_TRANSITION but may have been
2558 * clipped since vm_fault_wire() unlocks and relocks the
2559 * map. No matter how clipped it has gotten there should
2560 * be a fragment that is on our start boundary.
2562 CLIP_CHECK_BACK(start_entry
, start
);
2565 if (kmflags
& KM_PAGEABLE
) {
2567 * This is the unwiring case. We must first ensure that the
2568 * range to be unwired is really wired down. We know there
2571 entry
= start_entry
;
2572 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
2573 if (entry
->wired_count
== 0) {
2574 rv
= KERN_INVALID_ARGUMENT
;
2577 entry
= entry
->next
;
2581 * Now decrement the wiring count for each region. If a region
2582 * becomes completely unwired, unwire its physical pages and
2585 entry
= start_entry
;
2586 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
2587 entry
->wired_count
--;
2588 if (entry
->wired_count
== 0)
2589 vm_fault_unwire(map
, entry
);
2590 entry
= entry
->next
;
2594 vm_map_unclip_range(map
, start_entry
, start
, real_end
,
2595 &count
, MAP_CLIP_NO_HOLES
);
2599 if (kmflags
& KM_KRESERVE
)
2600 vm_map_entry_krelease(count
);
2602 vm_map_entry_release(count
);
2607 * Mark a newly allocated address range as wired but do not fault in
2608 * the pages. The caller is expected to load the pages into the object.
2610 * The map must be locked on entry and will remain locked on return.
2611 * No other requirements.
2614 vm_map_set_wired_quick(vm_map_t map
, vm_offset_t addr
, vm_size_t size
,
2617 vm_map_entry_t scan
;
2618 vm_map_entry_t entry
;
2620 entry
= vm_map_clip_range(map
, addr
, addr
+ size
,
2621 countp
, MAP_CLIP_NO_HOLES
);
2623 scan
!= &map
->header
&& scan
->start
< addr
+ size
;
2624 scan
= scan
->next
) {
2625 KKASSERT(scan
->wired_count
== 0);
2626 scan
->wired_count
= 1;
2628 vm_map_unclip_range(map
, entry
, addr
, addr
+ size
,
2629 countp
, MAP_CLIP_NO_HOLES
);
2633 * Push any dirty cached pages in the address range to their pager.
2634 * If syncio is TRUE, dirty pages are written synchronously.
2635 * If invalidate is TRUE, any cached pages are freed as well.
2637 * This routine is called by sys_msync()
2639 * Returns an error if any part of the specified range is not mapped.
2644 vm_map_clean(vm_map_t map
, vm_offset_t start
, vm_offset_t end
,
2645 boolean_t syncio
, boolean_t invalidate
)
2647 vm_map_entry_t current
;
2648 vm_map_entry_t entry
;
2652 vm_ooffset_t offset
;
2654 vm_map_lock_read(map
);
2655 VM_MAP_RANGE_CHECK(map
, start
, end
);
2656 if (!vm_map_lookup_entry(map
, start
, &entry
)) {
2657 vm_map_unlock_read(map
);
2658 return (KERN_INVALID_ADDRESS
);
2660 lwkt_gettoken(&map
->token
);
2663 * Make a first pass to check for holes.
2665 for (current
= entry
; current
->start
< end
; current
= current
->next
) {
2666 if (current
->maptype
== VM_MAPTYPE_SUBMAP
) {
2667 lwkt_reltoken(&map
->token
);
2668 vm_map_unlock_read(map
);
2669 return (KERN_INVALID_ARGUMENT
);
2671 if (end
> current
->end
&&
2672 (current
->next
== &map
->header
||
2673 current
->end
!= current
->next
->start
)) {
2674 lwkt_reltoken(&map
->token
);
2675 vm_map_unlock_read(map
);
2676 return (KERN_INVALID_ADDRESS
);
2681 pmap_remove(vm_map_pmap(map
), start
, end
);
2684 * Make a second pass, cleaning/uncaching pages from the indicated
2687 for (current
= entry
; current
->start
< end
; current
= current
->next
) {
2688 offset
= current
->offset
+ (start
- current
->start
);
2689 size
= (end
<= current
->end
? end
: current
->end
) - start
;
2691 switch(current
->maptype
) {
2692 case VM_MAPTYPE_SUBMAP
:
2695 vm_map_entry_t tentry
;
2698 smap
= current
->object
.sub_map
;
2699 vm_map_lock_read(smap
);
2700 vm_map_lookup_entry(smap
, offset
, &tentry
);
2701 tsize
= tentry
->end
- offset
;
2704 object
= tentry
->object
.vm_object
;
2705 offset
= tentry
->offset
+ (offset
- tentry
->start
);
2706 vm_map_unlock_read(smap
);
2709 case VM_MAPTYPE_NORMAL
:
2710 case VM_MAPTYPE_VPAGETABLE
:
2711 object
= current
->object
.vm_object
;
2719 vm_object_hold(object
);
2722 * Note that there is absolutely no sense in writing out
2723 * anonymous objects, so we track down the vnode object
2725 * We invalidate (remove) all pages from the address space
2726 * anyway, for semantic correctness.
2728 * note: certain anonymous maps, such as MAP_NOSYNC maps,
2729 * may start out with a NULL object.
2731 while (object
&& (tobj
= object
->backing_object
) != NULL
) {
2732 vm_object_hold(tobj
);
2733 if (tobj
== object
->backing_object
) {
2734 vm_object_lock_swap();
2735 offset
+= object
->backing_object_offset
;
2736 vm_object_drop(object
);
2738 if (object
->size
< OFF_TO_IDX(offset
+ size
))
2739 size
= IDX_TO_OFF(object
->size
) -
2743 vm_object_drop(tobj
);
2745 if (object
&& (object
->type
== OBJT_VNODE
) &&
2746 (current
->protection
& VM_PROT_WRITE
) &&
2747 (object
->flags
& OBJ_NOMSYNC
) == 0) {
2749 * Flush pages if writing is allowed, invalidate them
2750 * if invalidation requested. Pages undergoing I/O
2751 * will be ignored by vm_object_page_remove().
2753 * We cannot lock the vnode and then wait for paging
2754 * to complete without deadlocking against vm_fault.
2755 * Instead we simply call vm_object_page_remove() and
2756 * allow it to block internally on a page-by-page
2757 * basis when it encounters pages undergoing async
2762 /* no chain wait needed for vnode objects */
2763 vm_object_reference_locked(object
);
2764 vn_lock(object
->handle
, LK_EXCLUSIVE
| LK_RETRY
);
2765 flags
= (syncio
|| invalidate
) ? OBJPC_SYNC
: 0;
2766 flags
|= invalidate
? OBJPC_INVAL
: 0;
2769 * When operating on a virtual page table just
2770 * flush the whole object. XXX we probably ought
2773 switch(current
->maptype
) {
2774 case VM_MAPTYPE_NORMAL
:
2775 vm_object_page_clean(object
,
2777 OFF_TO_IDX(offset
+ size
+ PAGE_MASK
),
2780 case VM_MAPTYPE_VPAGETABLE
:
2781 vm_object_page_clean(object
, 0, 0, flags
);
2784 vn_unlock(((struct vnode
*)object
->handle
));
2785 vm_object_deallocate_locked(object
);
2787 if (object
&& invalidate
&&
2788 ((object
->type
== OBJT_VNODE
) ||
2789 (object
->type
== OBJT_DEVICE
) ||
2790 (object
->type
== OBJT_MGTDEVICE
))) {
2792 ((object
->type
== OBJT_DEVICE
) ||
2793 (object
->type
== OBJT_MGTDEVICE
)) ? FALSE
: TRUE
;
2794 /* no chain wait needed for vnode/device objects */
2795 vm_object_reference_locked(object
);
2796 switch(current
->maptype
) {
2797 case VM_MAPTYPE_NORMAL
:
2798 vm_object_page_remove(object
,
2800 OFF_TO_IDX(offset
+ size
+ PAGE_MASK
),
2803 case VM_MAPTYPE_VPAGETABLE
:
2804 vm_object_page_remove(object
, 0, 0, clean_only
);
2807 vm_object_deallocate_locked(object
);
2811 vm_object_drop(object
);
2814 lwkt_reltoken(&map
->token
);
2815 vm_map_unlock_read(map
);
2817 return (KERN_SUCCESS
);
2821 * Make the region specified by this entry pageable.
2823 * The vm_map must be exclusively locked.
2826 vm_map_entry_unwire(vm_map_t map
, vm_map_entry_t entry
)
2828 entry
->eflags
&= ~MAP_ENTRY_USER_WIRED
;
2829 entry
->wired_count
= 0;
2830 vm_fault_unwire(map
, entry
);
2834 * Deallocate the given entry from the target map.
2836 * The vm_map must be exclusively locked.
2839 vm_map_entry_delete(vm_map_t map
, vm_map_entry_t entry
, int *countp
)
2841 vm_map_entry_unlink(map
, entry
);
2842 map
->size
-= entry
->end
- entry
->start
;
2844 switch(entry
->maptype
) {
2845 case VM_MAPTYPE_NORMAL
:
2846 case VM_MAPTYPE_VPAGETABLE
:
2847 case VM_MAPTYPE_SUBMAP
:
2848 vm_object_deallocate(entry
->object
.vm_object
);
2850 case VM_MAPTYPE_UKSMAP
:
2857 vm_map_entry_dispose(map
, entry
, countp
);
2861 * Deallocates the given address range from the target map.
2863 * The vm_map must be exclusively locked.
2866 vm_map_delete(vm_map_t map
, vm_offset_t start
, vm_offset_t end
, int *countp
)
2869 vm_map_entry_t entry
;
2870 vm_map_entry_t first_entry
;
2872 ASSERT_VM_MAP_LOCKED(map
);
2873 lwkt_gettoken(&map
->token
);
2876 * Find the start of the region, and clip it. Set entry to point
2877 * at the first record containing the requested address or, if no
2878 * such record exists, the next record with a greater address. The
2879 * loop will run from this point until a record beyond the termination
2880 * address is encountered.
2882 * map->hint must be adjusted to not point to anything we delete,
2883 * so set it to the entry prior to the one being deleted.
2885 * GGG see other GGG comment.
2887 if (vm_map_lookup_entry(map
, start
, &first_entry
)) {
2888 entry
= first_entry
;
2889 vm_map_clip_start(map
, entry
, start
, countp
);
2890 map
->hint
= entry
->prev
; /* possible problem XXX */
2892 map
->hint
= first_entry
; /* possible problem XXX */
2893 entry
= first_entry
->next
;
2897 * If a hole opens up prior to the current first_free then
2898 * adjust first_free. As with map->hint, map->first_free
2899 * cannot be left set to anything we might delete.
2901 if (entry
== &map
->header
) {
2902 map
->first_free
= &map
->header
;
2903 } else if (map
->first_free
->start
>= start
) {
2904 map
->first_free
= entry
->prev
;
2908 * Step through all entries in this region
2910 while ((entry
!= &map
->header
) && (entry
->start
< end
)) {
2911 vm_map_entry_t next
;
2913 vm_pindex_t offidxstart
, offidxend
, count
;
2916 * If we hit an in-transition entry we have to sleep and
2917 * retry. It's easier (and not really slower) to just retry
2918 * since this case occurs so rarely and the hint is already
2919 * pointing at the right place. We have to reset the
2920 * start offset so as not to accidently delete an entry
2921 * another process just created in vacated space.
2923 if (entry
->eflags
& MAP_ENTRY_IN_TRANSITION
) {
2924 entry
->eflags
|= MAP_ENTRY_NEEDS_WAKEUP
;
2925 start
= entry
->start
;
2926 ++mycpu
->gd_cnt
.v_intrans_coll
;
2927 ++mycpu
->gd_cnt
.v_intrans_wait
;
2928 vm_map_transition_wait(map
);
2931 vm_map_clip_end(map
, entry
, end
, countp
);
2937 offidxstart
= OFF_TO_IDX(entry
->offset
);
2938 count
= OFF_TO_IDX(e
- s
);
2940 switch(entry
->maptype
) {
2941 case VM_MAPTYPE_NORMAL
:
2942 case VM_MAPTYPE_VPAGETABLE
:
2943 case VM_MAPTYPE_SUBMAP
:
2944 object
= entry
->object
.vm_object
;
2952 * Unwire before removing addresses from the pmap; otherwise,
2953 * unwiring will put the entries back in the pmap.
2955 if (entry
->wired_count
!= 0)
2956 vm_map_entry_unwire(map
, entry
);
2958 offidxend
= offidxstart
+ count
;
2960 if (object
== &kernel_object
) {
2961 vm_object_hold(object
);
2962 vm_object_page_remove(object
, offidxstart
,
2964 vm_object_drop(object
);
2965 } else if (object
&& object
->type
!= OBJT_DEFAULT
&&
2966 object
->type
!= OBJT_SWAP
) {
2968 * vnode object routines cannot be chain-locked,
2969 * but since we aren't removing pages from the
2970 * object here we can use a shared hold.
2972 vm_object_hold_shared(object
);
2973 pmap_remove(map
->pmap
, s
, e
);
2974 vm_object_drop(object
);
2975 } else if (object
) {
2976 vm_object_hold(object
);
2977 vm_object_chain_acquire(object
, 0);
2978 pmap_remove(map
->pmap
, s
, e
);
2980 if (object
!= NULL
&&
2981 object
->ref_count
!= 1 &&
2982 (object
->flags
& (OBJ_NOSPLIT
|OBJ_ONEMAPPING
)) ==
2984 (object
->type
== OBJT_DEFAULT
||
2985 object
->type
== OBJT_SWAP
)) {
2986 vm_object_collapse(object
, NULL
);
2987 vm_object_page_remove(object
, offidxstart
,
2989 if (object
->type
== OBJT_SWAP
) {
2990 swap_pager_freespace(object
,
2994 if (offidxend
>= object
->size
&&
2995 offidxstart
< object
->size
) {
2996 object
->size
= offidxstart
;
2999 vm_object_chain_release(object
);
3000 vm_object_drop(object
);
3001 } else if (entry
->maptype
== VM_MAPTYPE_UKSMAP
) {
3002 pmap_remove(map
->pmap
, s
, e
);
3006 * Delete the entry (which may delete the object) only after
3007 * removing all pmap entries pointing to its pages.
3008 * (Otherwise, its page frames may be reallocated, and any
3009 * modify bits will be set in the wrong object!)
3011 vm_map_entry_delete(map
, entry
, countp
);
3014 lwkt_reltoken(&map
->token
);
3015 return (KERN_SUCCESS
);
3019 * Remove the given address range from the target map.
3020 * This is the exported form of vm_map_delete.
3025 vm_map_remove(vm_map_t map
, vm_offset_t start
, vm_offset_t end
)
3030 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
3032 VM_MAP_RANGE_CHECK(map
, start
, end
);
3033 result
= vm_map_delete(map
, start
, end
, &count
);
3035 vm_map_entry_release(count
);
3041 * Assert that the target map allows the specified privilege on the
3042 * entire address region given. The entire region must be allocated.
3044 * The caller must specify whether the vm_map is already locked or not.
3047 vm_map_check_protection(vm_map_t map
, vm_offset_t start
, vm_offset_t end
,
3048 vm_prot_t protection
, boolean_t have_lock
)
3050 vm_map_entry_t entry
;
3051 vm_map_entry_t tmp_entry
;
3054 if (have_lock
== FALSE
)
3055 vm_map_lock_read(map
);
3057 if (!vm_map_lookup_entry(map
, start
, &tmp_entry
)) {
3058 if (have_lock
== FALSE
)
3059 vm_map_unlock_read(map
);
3065 while (start
< end
) {
3066 if (entry
== &map
->header
) {
3074 if (start
< entry
->start
) {
3079 * Check protection associated with entry.
3082 if ((entry
->protection
& protection
) != protection
) {
3086 /* go to next entry */
3089 entry
= entry
->next
;
3091 if (have_lock
== FALSE
)
3092 vm_map_unlock_read(map
);
3097 * If appropriate this function shadows the original object with a new object
3098 * and moves the VM pages from the original object to the new object.
3099 * The original object will also be collapsed, if possible.
3101 * We can only do this for normal memory objects with a single mapping, and
3102 * it only makes sense to do it if there are 2 or more refs on the original
3103 * object. i.e. typically a memory object that has been extended into
3104 * multiple vm_map_entry's with non-overlapping ranges.
3106 * This makes it easier to remove unused pages and keeps object inheritance
3107 * from being a negative impact on memory usage.
3109 * On return the (possibly new) entry->object.vm_object will have an
3110 * additional ref on it for the caller to dispose of (usually by cloning
3111 * the vm_map_entry). The additional ref had to be done in this routine
3112 * to avoid racing a collapse. The object's ONEMAPPING flag will also be
3115 * The vm_map must be locked and its token held.
3118 vm_map_split(vm_map_entry_t entry
)
3121 vm_object_t oobject
, nobject
, bobject
;
3124 vm_pindex_t offidxstart
, offidxend
, idx
;
3126 vm_ooffset_t offset
;
3130 * Optimize away object locks for vnode objects. Important exit/exec
3133 * OBJ_ONEMAPPING doesn't apply to vnode objects but clear the flag
3136 oobject
= entry
->object
.vm_object
;
3137 if (oobject
->type
!= OBJT_DEFAULT
&& oobject
->type
!= OBJT_SWAP
) {
3138 vm_object_reference_quick(oobject
);
3139 vm_object_clear_flag(oobject
, OBJ_ONEMAPPING
);
3144 * Setup. Chain lock the original object throughout the entire
3145 * routine to prevent new page faults from occuring.
3147 * XXX can madvise WILLNEED interfere with us too?
3149 vm_object_hold(oobject
);
3150 vm_object_chain_acquire(oobject
, 0);
3153 * Original object cannot be split? Might have also changed state.
3155 if (oobject
->handle
== NULL
|| (oobject
->type
!= OBJT_DEFAULT
&&
3156 oobject
->type
!= OBJT_SWAP
)) {
3157 vm_object_chain_release(oobject
);
3158 vm_object_reference_locked(oobject
);
3159 vm_object_clear_flag(oobject
, OBJ_ONEMAPPING
);
3160 vm_object_drop(oobject
);
3165 * Collapse original object with its backing store as an
3166 * optimization to reduce chain lengths when possible.
3168 * If ref_count <= 1 there aren't other non-overlapping vm_map_entry's
3169 * for oobject, so there's no point collapsing it.
3171 * Then re-check whether the object can be split.
3173 vm_object_collapse(oobject
, NULL
);
3175 if (oobject
->ref_count
<= 1 ||
3176 (oobject
->type
!= OBJT_DEFAULT
&& oobject
->type
!= OBJT_SWAP
) ||
3177 (oobject
->flags
& (OBJ_NOSPLIT
|OBJ_ONEMAPPING
)) != OBJ_ONEMAPPING
) {
3178 vm_object_chain_release(oobject
);
3179 vm_object_reference_locked(oobject
);
3180 vm_object_clear_flag(oobject
, OBJ_ONEMAPPING
);
3181 vm_object_drop(oobject
);
3186 * Acquire the chain lock on the backing object.
3188 * Give bobject an additional ref count for when it will be shadowed
3192 if ((bobject
= oobject
->backing_object
) != NULL
) {
3193 if (bobject
->type
!= OBJT_VNODE
) {
3195 vm_object_hold(bobject
);
3196 vm_object_chain_wait(bobject
, 0);
3197 /* ref for shadowing below */
3198 vm_object_reference_locked(bobject
);
3199 vm_object_chain_acquire(bobject
, 0);
3200 KKASSERT(bobject
->backing_object
== bobject
);
3201 KKASSERT((bobject
->flags
& OBJ_DEAD
) == 0);
3204 * vnodes are not placed on the shadow list but
3205 * they still get another ref for the backing_object
3208 vm_object_reference_quick(bobject
);
3213 * Calculate the object page range and allocate the new object.
3215 offset
= entry
->offset
;
3219 offidxstart
= OFF_TO_IDX(offset
);
3220 offidxend
= offidxstart
+ OFF_TO_IDX(e
- s
);
3221 size
= offidxend
- offidxstart
;
3223 switch(oobject
->type
) {
3225 nobject
= default_pager_alloc(NULL
, IDX_TO_OFF(size
),
3229 nobject
= swap_pager_alloc(NULL
, IDX_TO_OFF(size
),
3238 if (nobject
== NULL
) {
3240 if (useshadowlist
) {
3241 vm_object_chain_release(bobject
);
3242 vm_object_deallocate(bobject
);
3243 vm_object_drop(bobject
);
3245 vm_object_deallocate(bobject
);
3248 vm_object_chain_release(oobject
);
3249 vm_object_reference_locked(oobject
);
3250 vm_object_clear_flag(oobject
, OBJ_ONEMAPPING
);
3251 vm_object_drop(oobject
);
3256 * The new object will replace entry->object.vm_object so it needs
3257 * a second reference (the caller expects an additional ref).
3259 vm_object_hold(nobject
);
3260 vm_object_reference_locked(nobject
);
3261 vm_object_chain_acquire(nobject
, 0);
3264 * nobject shadows bobject (oobject already shadows bobject).
3266 * Adding an object to bobject's shadow list requires refing bobject
3267 * which we did above in the useshadowlist case.
3270 nobject
->backing_object_offset
=
3271 oobject
->backing_object_offset
+ IDX_TO_OFF(offidxstart
);
3272 nobject
->backing_object
= bobject
;
3273 if (useshadowlist
) {
3274 bobject
->shadow_count
++;
3275 atomic_add_int(&bobject
->generation
, 1);
3276 LIST_INSERT_HEAD(&bobject
->shadow_head
,
3277 nobject
, shadow_list
);
3278 vm_object_clear_flag(bobject
, OBJ_ONEMAPPING
); /*XXX*/
3279 vm_object_chain_release(bobject
);
3280 vm_object_drop(bobject
);
3281 vm_object_set_flag(nobject
, OBJ_ONSHADOW
);
3286 * Move the VM pages from oobject to nobject
3288 for (idx
= 0; idx
< size
; idx
++) {
3291 m
= vm_page_lookup_busy_wait(oobject
, offidxstart
+ idx
,
3297 * We must wait for pending I/O to complete before we can
3300 * We do not have to VM_PROT_NONE the page as mappings should
3301 * not be changed by this operation.
3303 * NOTE: The act of renaming a page updates chaingen for both
3306 vm_page_rename(m
, nobject
, idx
);
3307 /* page automatically made dirty by rename and cache handled */
3308 /* page remains busy */
3311 if (oobject
->type
== OBJT_SWAP
) {
3312 vm_object_pip_add(oobject
, 1);
3314 * copy oobject pages into nobject and destroy unneeded
3315 * pages in shadow object.
3317 swap_pager_copy(oobject
, nobject
, offidxstart
, 0);
3318 vm_object_pip_wakeup(oobject
);
3322 * Wakeup the pages we played with. No spl protection is needed
3323 * for a simple wakeup.
3325 for (idx
= 0; idx
< size
; idx
++) {
3326 m
= vm_page_lookup(nobject
, idx
);
3328 KKASSERT(m
->flags
& PG_BUSY
);
3332 entry
->object
.vm_object
= nobject
;
3333 entry
->offset
= 0LL;
3338 * NOTE: There is no need to remove OBJ_ONEMAPPING from oobject, the
3339 * related pages were moved and are no longer applicable to the
3342 * NOTE: Deallocate oobject (due to its entry->object.vm_object being
3343 * replaced by nobject).
3345 vm_object_chain_release(nobject
);
3346 vm_object_drop(nobject
);
3347 if (bobject
&& useshadowlist
) {
3348 vm_object_chain_release(bobject
);
3349 vm_object_drop(bobject
);
3351 vm_object_chain_release(oobject
);
3352 /*vm_object_clear_flag(oobject, OBJ_ONEMAPPING);*/
3353 vm_object_deallocate_locked(oobject
);
3354 vm_object_drop(oobject
);
3358 * Copies the contents of the source entry to the destination
3359 * entry. The entries *must* be aligned properly.
3361 * The vm_maps must be exclusively locked.
3362 * The vm_map's token must be held.
3364 * Because the maps are locked no faults can be in progress during the
3368 vm_map_copy_entry(vm_map_t src_map
, vm_map_t dst_map
,
3369 vm_map_entry_t src_entry
, vm_map_entry_t dst_entry
)
3371 vm_object_t src_object
;
3373 if (dst_entry
->maptype
== VM_MAPTYPE_SUBMAP
||
3374 dst_entry
->maptype
== VM_MAPTYPE_UKSMAP
)
3376 if (src_entry
->maptype
== VM_MAPTYPE_SUBMAP
||
3377 src_entry
->maptype
== VM_MAPTYPE_UKSMAP
)
3380 if (src_entry
->wired_count
== 0) {
3382 * If the source entry is marked needs_copy, it is already
3385 if ((src_entry
->eflags
& MAP_ENTRY_NEEDS_COPY
) == 0) {
3386 pmap_protect(src_map
->pmap
,
3389 src_entry
->protection
& ~VM_PROT_WRITE
);
3393 * Make a copy of the object.
3395 * The object must be locked prior to checking the object type
3396 * and for the call to vm_object_collapse() and vm_map_split().
3397 * We cannot use *_hold() here because the split code will
3398 * probably try to destroy the object. The lock is a pool
3399 * token and doesn't care.
3401 * We must bump src_map->timestamp when setting
3402 * MAP_ENTRY_NEEDS_COPY to force any concurrent fault
3403 * to retry, otherwise the concurrent fault might improperly
3404 * install a RW pte when its supposed to be a RO(COW) pte.
3405 * This race can occur because a vnode-backed fault may have
3406 * to temporarily release the map lock.
3408 if (src_entry
->object
.vm_object
!= NULL
) {
3409 vm_map_split(src_entry
);
3410 src_object
= src_entry
->object
.vm_object
;
3411 dst_entry
->object
.vm_object
= src_object
;
3412 src_entry
->eflags
|= (MAP_ENTRY_COW
|
3413 MAP_ENTRY_NEEDS_COPY
);
3414 dst_entry
->eflags
|= (MAP_ENTRY_COW
|
3415 MAP_ENTRY_NEEDS_COPY
);
3416 dst_entry
->offset
= src_entry
->offset
;
3417 ++src_map
->timestamp
;
3419 dst_entry
->object
.vm_object
= NULL
;
3420 dst_entry
->offset
= 0;
3423 pmap_copy(dst_map
->pmap
, src_map
->pmap
, dst_entry
->start
,
3424 dst_entry
->end
- dst_entry
->start
, src_entry
->start
);
3427 * Of course, wired down pages can't be set copy-on-write.
3428 * Cause wired pages to be copied into the new map by
3429 * simulating faults (the new pages are pageable)
3431 vm_fault_copy_entry(dst_map
, src_map
, dst_entry
, src_entry
);
3437 * Create a new process vmspace structure and vm_map
3438 * based on those of an existing process. The new map
3439 * is based on the old map, according to the inheritance
3440 * values on the regions in that map.
3442 * The source map must not be locked.
3445 static void vmspace_fork_normal_entry(vm_map_t old_map
, vm_map_t new_map
,
3446 vm_map_entry_t old_entry
, int *countp
);
3447 static void vmspace_fork_uksmap_entry(vm_map_t old_map
, vm_map_t new_map
,
3448 vm_map_entry_t old_entry
, int *countp
);
3451 vmspace_fork(struct vmspace
*vm1
)
3453 struct vmspace
*vm2
;
3454 vm_map_t old_map
= &vm1
->vm_map
;
3456 vm_map_entry_t old_entry
;
3459 lwkt_gettoken(&vm1
->vm_map
.token
);
3460 vm_map_lock(old_map
);
3462 vm2
= vmspace_alloc(old_map
->min_offset
, old_map
->max_offset
);
3463 lwkt_gettoken(&vm2
->vm_map
.token
);
3464 bcopy(&vm1
->vm_startcopy
, &vm2
->vm_startcopy
,
3465 (caddr_t
)&vm1
->vm_endcopy
- (caddr_t
)&vm1
->vm_startcopy
);
3466 new_map
= &vm2
->vm_map
; /* XXX */
3467 new_map
->timestamp
= 1;
3469 vm_map_lock(new_map
);
3472 old_entry
= old_map
->header
.next
;
3473 while (old_entry
!= &old_map
->header
) {
3475 old_entry
= old_entry
->next
;
3478 count
= vm_map_entry_reserve(count
+ MAP_RESERVE_COUNT
);
3480 old_entry
= old_map
->header
.next
;
3481 while (old_entry
!= &old_map
->header
) {
3482 switch(old_entry
->maptype
) {
3483 case VM_MAPTYPE_SUBMAP
:
3484 panic("vm_map_fork: encountered a submap");
3486 case VM_MAPTYPE_UKSMAP
:
3487 vmspace_fork_uksmap_entry(old_map
, new_map
,
3490 case VM_MAPTYPE_NORMAL
:
3491 case VM_MAPTYPE_VPAGETABLE
:
3492 vmspace_fork_normal_entry(old_map
, new_map
,
3496 old_entry
= old_entry
->next
;
3499 new_map
->size
= old_map
->size
;
3500 vm_map_unlock(old_map
);
3501 vm_map_unlock(new_map
);
3502 vm_map_entry_release(count
);
3504 lwkt_reltoken(&vm2
->vm_map
.token
);
3505 lwkt_reltoken(&vm1
->vm_map
.token
);
3512 vmspace_fork_normal_entry(vm_map_t old_map
, vm_map_t new_map
,
3513 vm_map_entry_t old_entry
, int *countp
)
3515 vm_map_entry_t new_entry
;
3518 switch (old_entry
->inheritance
) {
3519 case VM_INHERIT_NONE
:
3521 case VM_INHERIT_SHARE
:
3523 * Clone the entry, creating the shared object if
3526 if (old_entry
->object
.vm_object
== NULL
)
3527 vm_map_entry_allocate_object(old_entry
);
3529 if (old_entry
->eflags
& MAP_ENTRY_NEEDS_COPY
) {
3531 * Shadow a map_entry which needs a copy,
3532 * replacing its object with a new object
3533 * that points to the old one. Ask the
3534 * shadow code to automatically add an
3535 * additional ref. We can't do it afterwords
3536 * because we might race a collapse. The call
3537 * to vm_map_entry_shadow() will also clear
3540 vm_map_entry_shadow(old_entry
, 1);
3541 } else if (old_entry
->object
.vm_object
) {
3543 * We will make a shared copy of the object,
3544 * and must clear OBJ_ONEMAPPING.
3546 * Optimize vnode objects. OBJ_ONEMAPPING
3547 * is non-applicable but clear it anyway,
3548 * and its terminal so we don'th ave to deal
3549 * with chains. Reduces SMP conflicts.
3551 * XXX assert that object.vm_object != NULL
3552 * since we allocate it above.
3554 object
= old_entry
->object
.vm_object
;
3555 if (object
->type
== OBJT_VNODE
) {
3556 vm_object_reference_quick(object
);
3557 vm_object_clear_flag(object
,
3560 vm_object_hold(object
);
3561 vm_object_chain_wait(object
, 0);
3562 vm_object_reference_locked(object
);
3563 vm_object_clear_flag(object
,
3565 vm_object_drop(object
);
3570 * Clone the entry. We've already bumped the ref on
3573 new_entry
= vm_map_entry_create(new_map
, countp
);
3574 *new_entry
= *old_entry
;
3575 new_entry
->eflags
&= ~MAP_ENTRY_USER_WIRED
;
3576 new_entry
->wired_count
= 0;
3579 * Insert the entry into the new map -- we know we're
3580 * inserting at the end of the new map.
3583 vm_map_entry_link(new_map
, new_map
->header
.prev
,
3587 * Update the physical map
3589 pmap_copy(new_map
->pmap
, old_map
->pmap
,
3591 (old_entry
->end
- old_entry
->start
),
3594 case VM_INHERIT_COPY
:
3596 * Clone the entry and link into the map.
3598 new_entry
= vm_map_entry_create(new_map
, countp
);
3599 *new_entry
= *old_entry
;
3600 new_entry
->eflags
&= ~MAP_ENTRY_USER_WIRED
;
3601 new_entry
->wired_count
= 0;
3602 new_entry
->object
.vm_object
= NULL
;
3603 vm_map_entry_link(new_map
, new_map
->header
.prev
,
3605 vm_map_copy_entry(old_map
, new_map
, old_entry
,
3612 * When forking user-kernel shared maps, the map might change in the
3613 * child so do not try to copy the underlying pmap entries.
3617 vmspace_fork_uksmap_entry(vm_map_t old_map
, vm_map_t new_map
,
3618 vm_map_entry_t old_entry
, int *countp
)
3620 vm_map_entry_t new_entry
;
3622 new_entry
= vm_map_entry_create(new_map
, countp
);
3623 *new_entry
= *old_entry
;
3624 new_entry
->eflags
&= ~MAP_ENTRY_USER_WIRED
;
3625 new_entry
->wired_count
= 0;
3626 vm_map_entry_link(new_map
, new_map
->header
.prev
,
3631 * Create an auto-grow stack entry
3636 vm_map_stack (vm_map_t map
, vm_offset_t addrbos
, vm_size_t max_ssize
,
3637 int flags
, vm_prot_t prot
, vm_prot_t max
, int cow
)
3639 vm_map_entry_t prev_entry
;
3640 vm_map_entry_t new_stack_entry
;
3641 vm_size_t init_ssize
;
3644 vm_offset_t tmpaddr
;
3646 cow
|= MAP_IS_STACK
;
3648 if (max_ssize
< sgrowsiz
)
3649 init_ssize
= max_ssize
;
3651 init_ssize
= sgrowsiz
;
3653 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
3657 * Find space for the mapping
3659 if ((flags
& (MAP_FIXED
| MAP_TRYFIXED
)) == 0) {
3660 if (vm_map_findspace(map
, addrbos
, max_ssize
, 1,
3663 vm_map_entry_release(count
);
3664 return (KERN_NO_SPACE
);
3669 /* If addr is already mapped, no go */
3670 if (vm_map_lookup_entry(map
, addrbos
, &prev_entry
)) {
3672 vm_map_entry_release(count
);
3673 return (KERN_NO_SPACE
);
3677 /* XXX already handled by kern_mmap() */
3678 /* If we would blow our VMEM resource limit, no go */
3679 if (map
->size
+ init_ssize
>
3680 curproc
->p_rlimit
[RLIMIT_VMEM
].rlim_cur
) {
3682 vm_map_entry_release(count
);
3683 return (KERN_NO_SPACE
);
3688 * If we can't accomodate max_ssize in the current mapping,
3689 * no go. However, we need to be aware that subsequent user
3690 * mappings might map into the space we have reserved for
3691 * stack, and currently this space is not protected.
3693 * Hopefully we will at least detect this condition
3694 * when we try to grow the stack.
3696 if ((prev_entry
->next
!= &map
->header
) &&
3697 (prev_entry
->next
->start
< addrbos
+ max_ssize
)) {
3699 vm_map_entry_release(count
);
3700 return (KERN_NO_SPACE
);
3704 * We initially map a stack of only init_ssize. We will
3705 * grow as needed later. Since this is to be a grow
3706 * down stack, we map at the top of the range.
3708 * Note: we would normally expect prot and max to be
3709 * VM_PROT_ALL, and cow to be 0. Possibly we should
3710 * eliminate these as input parameters, and just
3711 * pass these values here in the insert call.
3713 rv
= vm_map_insert(map
, &count
, NULL
, NULL
,
3714 0, addrbos
+ max_ssize
- init_ssize
,
3715 addrbos
+ max_ssize
,
3717 VM_SUBSYS_STACK
, prot
, max
, cow
);
3719 /* Now set the avail_ssize amount */
3720 if (rv
== KERN_SUCCESS
) {
3721 if (prev_entry
!= &map
->header
)
3722 vm_map_clip_end(map
, prev_entry
, addrbos
+ max_ssize
- init_ssize
, &count
);
3723 new_stack_entry
= prev_entry
->next
;
3724 if (new_stack_entry
->end
!= addrbos
+ max_ssize
||
3725 new_stack_entry
->start
!= addrbos
+ max_ssize
- init_ssize
)
3726 panic ("Bad entry start/end for new stack entry");
3728 new_stack_entry
->aux
.avail_ssize
= max_ssize
- init_ssize
;
3732 vm_map_entry_release(count
);
3737 * Attempts to grow a vm stack entry. Returns KERN_SUCCESS if the
3738 * desired address is already mapped, or if we successfully grow
3739 * the stack. Also returns KERN_SUCCESS if addr is outside the
3740 * stack range (this is strange, but preserves compatibility with
3741 * the grow function in vm_machdep.c).
3746 vm_map_growstack (vm_map_t map
, vm_offset_t addr
)
3748 vm_map_entry_t prev_entry
;
3749 vm_map_entry_t stack_entry
;
3750 vm_map_entry_t new_stack_entry
;
3756 int rv
= KERN_SUCCESS
;
3758 int use_read_lock
= 1;
3764 lp
= curthread
->td_lwp
;
3765 p
= curthread
->td_proc
;
3766 KKASSERT(lp
!= NULL
);
3767 vm
= lp
->lwp_vmspace
;
3770 * Growstack is only allowed on the current process. We disallow
3771 * other use cases, e.g. trying to access memory via procfs that
3772 * the stack hasn't grown into.
3774 if (map
!= &vm
->vm_map
) {
3775 return KERN_FAILURE
;
3778 count
= vm_map_entry_reserve(MAP_RESERVE_COUNT
);
3781 vm_map_lock_read(map
);
3785 /* If addr is already in the entry range, no need to grow.*/
3786 if (vm_map_lookup_entry(map
, addr
, &prev_entry
))
3789 if ((stack_entry
= prev_entry
->next
) == &map
->header
)
3791 if (prev_entry
== &map
->header
)
3792 end
= stack_entry
->start
- stack_entry
->aux
.avail_ssize
;
3794 end
= prev_entry
->end
;
3797 * This next test mimics the old grow function in vm_machdep.c.
3798 * It really doesn't quite make sense, but we do it anyway
3799 * for compatibility.
3801 * If not growable stack, return success. This signals the
3802 * caller to proceed as he would normally with normal vm.
3804 if (stack_entry
->aux
.avail_ssize
< 1 ||
3805 addr
>= stack_entry
->start
||
3806 addr
< stack_entry
->start
- stack_entry
->aux
.avail_ssize
) {
3810 /* Find the minimum grow amount */
3811 grow_amount
= roundup (stack_entry
->start
- addr
, PAGE_SIZE
);
3812 if (grow_amount
> stack_entry
->aux
.avail_ssize
) {
3818 * If there is no longer enough space between the entries
3819 * nogo, and adjust the available space. Note: this
3820 * should only happen if the user has mapped into the
3821 * stack area after the stack was created, and is
3822 * probably an error.
3824 * This also effectively destroys any guard page the user
3825 * might have intended by limiting the stack size.
3827 if (grow_amount
> stack_entry
->start
- end
) {
3828 if (use_read_lock
&& vm_map_lock_upgrade(map
)) {
3834 stack_entry
->aux
.avail_ssize
= stack_entry
->start
- end
;
3839 is_procstack
= addr
>= (vm_offset_t
)vm
->vm_maxsaddr
;
3841 /* If this is the main process stack, see if we're over the
3844 if (is_procstack
&& (ctob(vm
->vm_ssize
) + grow_amount
>
3845 p
->p_rlimit
[RLIMIT_STACK
].rlim_cur
)) {
3850 /* Round up the grow amount modulo SGROWSIZ */
3851 grow_amount
= roundup (grow_amount
, sgrowsiz
);
3852 if (grow_amount
> stack_entry
->aux
.avail_ssize
) {
3853 grow_amount
= stack_entry
->aux
.avail_ssize
;
3855 if (is_procstack
&& (ctob(vm
->vm_ssize
) + grow_amount
>
3856 p
->p_rlimit
[RLIMIT_STACK
].rlim_cur
)) {
3857 grow_amount
= p
->p_rlimit
[RLIMIT_STACK
].rlim_cur
-
3861 /* If we would blow our VMEM resource limit, no go */
3862 if (map
->size
+ grow_amount
> p
->p_rlimit
[RLIMIT_VMEM
].rlim_cur
) {
3867 if (use_read_lock
&& vm_map_lock_upgrade(map
)) {
3874 /* Get the preliminary new entry start value */
3875 addr
= stack_entry
->start
- grow_amount
;
3877 /* If this puts us into the previous entry, cut back our growth
3878 * to the available space. Also, see the note above.
3881 stack_entry
->aux
.avail_ssize
= stack_entry
->start
- end
;
3885 rv
= vm_map_insert(map
, &count
, NULL
, NULL
,
3886 0, addr
, stack_entry
->start
,
3888 VM_SUBSYS_STACK
, VM_PROT_ALL
, VM_PROT_ALL
, 0);
3890 /* Adjust the available stack space by the amount we grew. */
3891 if (rv
== KERN_SUCCESS
) {
3892 if (prev_entry
!= &map
->header
)
3893 vm_map_clip_end(map
, prev_entry
, addr
, &count
);
3894 new_stack_entry
= prev_entry
->next
;
3895 if (new_stack_entry
->end
!= stack_entry
->start
||
3896 new_stack_entry
->start
!= addr
)
3897 panic ("Bad stack grow start/end in new stack entry");
3899 new_stack_entry
->aux
.avail_ssize
=
3900 stack_entry
->aux
.avail_ssize
-
3901 (new_stack_entry
->end
- new_stack_entry
->start
);
3903 vm
->vm_ssize
+= btoc(new_stack_entry
->end
-
3904 new_stack_entry
->start
);
3907 if (map
->flags
& MAP_WIREFUTURE
)
3908 vm_map_unwire(map
, new_stack_entry
->start
,
3909 new_stack_entry
->end
, FALSE
);
3914 vm_map_unlock_read(map
);
3917 vm_map_entry_release(count
);
3922 * Unshare the specified VM space for exec. If other processes are
3923 * mapped to it, then create a new one. The new vmspace is null.
3928 vmspace_exec(struct proc
*p
, struct vmspace
*vmcopy
)
3930 struct vmspace
*oldvmspace
= p
->p_vmspace
;
3931 struct vmspace
*newvmspace
;
3932 vm_map_t map
= &p
->p_vmspace
->vm_map
;
3935 * If we are execing a resident vmspace we fork it, otherwise
3936 * we create a new vmspace. Note that exitingcnt is not
3937 * copied to the new vmspace.
3939 lwkt_gettoken(&oldvmspace
->vm_map
.token
);
3941 newvmspace
= vmspace_fork(vmcopy
);
3942 lwkt_gettoken(&newvmspace
->vm_map
.token
);
3944 newvmspace
= vmspace_alloc(map
->min_offset
, map
->max_offset
);
3945 lwkt_gettoken(&newvmspace
->vm_map
.token
);
3946 bcopy(&oldvmspace
->vm_startcopy
, &newvmspace
->vm_startcopy
,
3947 (caddr_t
)&oldvmspace
->vm_endcopy
-
3948 (caddr_t
)&oldvmspace
->vm_startcopy
);
3952 * Finish initializing the vmspace before assigning it
3953 * to the process. The vmspace will become the current vmspace
3956 pmap_pinit2(vmspace_pmap(newvmspace
));
3957 pmap_replacevm(p
, newvmspace
, 0);
3958 lwkt_reltoken(&newvmspace
->vm_map
.token
);
3959 lwkt_reltoken(&oldvmspace
->vm_map
.token
);
3960 vmspace_rel(oldvmspace
);
3964 * Unshare the specified VM space for forcing COW. This
3965 * is called by rfork, for the (RFMEM|RFPROC) == 0 case.
3968 vmspace_unshare(struct proc
*p
)
3970 struct vmspace
*oldvmspace
= p
->p_vmspace
;
3971 struct vmspace
*newvmspace
;
3973 lwkt_gettoken(&oldvmspace
->vm_map
.token
);
3974 if (vmspace_getrefs(oldvmspace
) == 1) {
3975 lwkt_reltoken(&oldvmspace
->vm_map
.token
);
3978 newvmspace
= vmspace_fork(oldvmspace
);
3979 lwkt_gettoken(&newvmspace
->vm_map
.token
);
3980 pmap_pinit2(vmspace_pmap(newvmspace
));
3981 pmap_replacevm(p
, newvmspace
, 0);
3982 lwkt_reltoken(&newvmspace
->vm_map
.token
);
3983 lwkt_reltoken(&oldvmspace
->vm_map
.token
);
3984 vmspace_rel(oldvmspace
);
3988 * vm_map_hint: return the beginning of the best area suitable for
3989 * creating a new mapping with "prot" protection.
3994 vm_map_hint(struct proc
*p
, vm_offset_t addr
, vm_prot_t prot
)
3996 struct vmspace
*vms
= p
->p_vmspace
;
3998 if (!randomize_mmap
|| addr
!= 0) {
4000 * Set a reasonable start point for the hint if it was
4001 * not specified or if it falls within the heap space.
4002 * Hinted mmap()s do not allocate out of the heap space.
4005 (addr
>= round_page((vm_offset_t
)vms
->vm_taddr
) &&
4006 addr
< round_page((vm_offset_t
)vms
->vm_daddr
+ maxdsiz
))) {
4007 addr
= round_page((vm_offset_t
)vms
->vm_daddr
+ maxdsiz
);
4012 addr
= (vm_offset_t
)vms
->vm_daddr
+ MAXDSIZ
;
4013 addr
+= karc4random() & (MIN((256 * 1024 * 1024), MAXDSIZ
) - 1);
4015 return (round_page(addr
));
4019 * Finds the VM object, offset, and protection for a given virtual address
4020 * in the specified map, assuming a page fault of the type specified.
4022 * Leaves the map in question locked for read; return values are guaranteed
4023 * until a vm_map_lookup_done call is performed. Note that the map argument
4024 * is in/out; the returned map must be used in the call to vm_map_lookup_done.
4026 * A handle (out_entry) is returned for use in vm_map_lookup_done, to make
4029 * If a lookup is requested with "write protection" specified, the map may
4030 * be changed to perform virtual copying operations, although the data
4031 * referenced will remain the same.
4036 vm_map_lookup(vm_map_t
*var_map
, /* IN/OUT */
4038 vm_prot_t fault_typea
,
4039 vm_map_entry_t
*out_entry
, /* OUT */
4040 vm_object_t
*object
, /* OUT */
4041 vm_pindex_t
*pindex
, /* OUT */
4042 vm_prot_t
*out_prot
, /* OUT */
4043 boolean_t
*wired
) /* OUT */
4045 vm_map_entry_t entry
;
4046 vm_map_t map
= *var_map
;
4048 vm_prot_t fault_type
= fault_typea
;
4049 int use_read_lock
= 1;
4050 int rv
= KERN_SUCCESS
;
4054 vm_map_lock_read(map
);
4059 * If the map has an interesting hint, try it before calling full
4060 * blown lookup routine.
4067 if ((entry
== &map
->header
) ||
4068 (vaddr
< entry
->start
) || (vaddr
>= entry
->end
)) {
4069 vm_map_entry_t tmp_entry
;
4072 * Entry was either not a valid hint, or the vaddr was not
4073 * contained in the entry, so do a full lookup.
4075 if (!vm_map_lookup_entry(map
, vaddr
, &tmp_entry
)) {
4076 rv
= KERN_INVALID_ADDRESS
;
4087 if (entry
->maptype
== VM_MAPTYPE_SUBMAP
) {
4088 vm_map_t old_map
= map
;
4090 *var_map
= map
= entry
->object
.sub_map
;
4092 vm_map_unlock_read(old_map
);
4094 vm_map_unlock(old_map
);
4100 * Check whether this task is allowed to have this page.
4101 * Note the special case for MAP_ENTRY_COW pages with an override.
4102 * This is to implement a forced COW for debuggers.
4104 if (fault_type
& VM_PROT_OVERRIDE_WRITE
)
4105 prot
= entry
->max_protection
;
4107 prot
= entry
->protection
;
4109 fault_type
&= (VM_PROT_READ
|VM_PROT_WRITE
|VM_PROT_EXECUTE
);
4110 if ((fault_type
& prot
) != fault_type
) {
4111 rv
= KERN_PROTECTION_FAILURE
;
4115 if ((entry
->eflags
& MAP_ENTRY_USER_WIRED
) &&
4116 (entry
->eflags
& MAP_ENTRY_COW
) &&
4117 (fault_type
& VM_PROT_WRITE
) &&
4118 (fault_typea
& VM_PROT_OVERRIDE_WRITE
) == 0) {
4119 rv
= KERN_PROTECTION_FAILURE
;
4124 * If this page is not pageable, we have to get it for all possible
4127 *wired
= (entry
->wired_count
!= 0);
4129 prot
= fault_type
= entry
->protection
;
4132 * Virtual page tables may need to update the accessed (A) bit
4133 * in a page table entry. Upgrade the fault to a write fault for
4134 * that case if the map will support it. If the map does not support
4135 * it the page table entry simply will not be updated.
4137 if (entry
->maptype
== VM_MAPTYPE_VPAGETABLE
) {
4138 if (prot
& VM_PROT_WRITE
)
4139 fault_type
|= VM_PROT_WRITE
;
4142 if (curthread
->td_lwp
&& curthread
->td_lwp
->lwp_vmspace
&&
4143 pmap_emulate_ad_bits(&curthread
->td_lwp
->lwp_vmspace
->vm_pmap
)) {
4144 if ((prot
& VM_PROT_WRITE
) == 0)
4145 fault_type
|= VM_PROT_WRITE
;
4149 * Only NORMAL and VPAGETABLE maps are object-based. UKSMAPs are not.
4151 if (entry
->maptype
!= VM_MAPTYPE_NORMAL
&&
4152 entry
->maptype
!= VM_MAPTYPE_VPAGETABLE
) {
4158 * If the entry was copy-on-write, we either ...
4160 if (entry
->eflags
& MAP_ENTRY_NEEDS_COPY
) {
4162 * If we want to write the page, we may as well handle that
4163 * now since we've got the map locked.
4165 * If we don't need to write the page, we just demote the
4166 * permissions allowed.
4169 if (fault_type
& VM_PROT_WRITE
) {
4171 * Not allowed if TDF_NOFAULT is set as the shadowing
4172 * operation can deadlock against the faulting
4173 * function due to the copy-on-write.
4175 if (curthread
->td_flags
& TDF_NOFAULT
) {
4176 rv
= KERN_FAILURE_NOFAULT
;
4181 * Make a new object, and place it in the object
4182 * chain. Note that no new references have appeared
4183 * -- one just moved from the map to the new
4187 if (use_read_lock
&& vm_map_lock_upgrade(map
)) {
4194 vm_map_entry_shadow(entry
, 0);
4197 * We're attempting to read a copy-on-write page --
4198 * don't allow writes.
4201 prot
&= ~VM_PROT_WRITE
;
4206 * Create an object if necessary.
4208 if (entry
->object
.vm_object
== NULL
&& !map
->system_map
) {
4209 if (use_read_lock
&& vm_map_lock_upgrade(map
)) {
4215 vm_map_entry_allocate_object(entry
);
4219 * Return the object/offset from this entry. If the entry was
4220 * copy-on-write or empty, it has been fixed up.
4222 *object
= entry
->object
.vm_object
;
4225 *pindex
= OFF_TO_IDX((vaddr
- entry
->start
) + entry
->offset
);
4228 * Return whether this is the only map sharing this data. On
4229 * success we return with a read lock held on the map. On failure
4230 * we return with the map unlocked.
4234 if (rv
== KERN_SUCCESS
) {
4235 if (use_read_lock
== 0)
4236 vm_map_lock_downgrade(map
);
4237 } else if (use_read_lock
) {
4238 vm_map_unlock_read(map
);
4246 * Releases locks acquired by a vm_map_lookup()
4247 * (according to the handle returned by that lookup).
4249 * No other requirements.
4252 vm_map_lookup_done(vm_map_t map
, vm_map_entry_t entry
, int count
)
4255 * Unlock the main-level map
4257 vm_map_unlock_read(map
);
4259 vm_map_entry_release(count
);
4263 * Quick hack, needs some help to make it more SMP friendly.
4266 vm_map_interlock(vm_map_t map
, struct vm_map_ilock
*ilock
,
4267 vm_offset_t ran_beg
, vm_offset_t ran_end
)
4269 struct vm_map_ilock
*scan
;
4271 ilock
->ran_beg
= ran_beg
;
4272 ilock
->ran_end
= ran_end
;
4275 spin_lock(&map
->ilock_spin
);
4277 for (scan
= map
->ilock_base
; scan
; scan
= scan
->next
) {
4278 if (ran_end
> scan
->ran_beg
&& ran_beg
< scan
->ran_end
) {
4279 scan
->flags
|= ILOCK_WAITING
;
4280 ssleep(scan
, &map
->ilock_spin
, 0, "ilock", 0);
4284 ilock
->next
= map
->ilock_base
;
4285 map
->ilock_base
= ilock
;
4286 spin_unlock(&map
->ilock_spin
);
4290 vm_map_deinterlock(vm_map_t map
, struct vm_map_ilock
*ilock
)
4292 struct vm_map_ilock
*scan
;
4293 struct vm_map_ilock
**scanp
;
4295 spin_lock(&map
->ilock_spin
);
4296 scanp
= &map
->ilock_base
;
4297 while ((scan
= *scanp
) != NULL
) {
4298 if (scan
== ilock
) {
4299 *scanp
= ilock
->next
;
4300 spin_unlock(&map
->ilock_spin
);
4301 if (ilock
->flags
& ILOCK_WAITING
)
4305 scanp
= &scan
->next
;
4307 spin_unlock(&map
->ilock_spin
);
4308 panic("vm_map_deinterlock: missing ilock!");
4311 #include "opt_ddb.h"
4313 #include <ddb/ddb.h>
4318 DB_SHOW_COMMAND(map
, vm_map_print
)
4321 /* XXX convert args. */
4322 vm_map_t map
= (vm_map_t
)addr
;
4323 boolean_t full
= have_addr
;
4325 vm_map_entry_t entry
;
4327 db_iprintf("Task map %p: pmap=%p, nentries=%d, version=%u\n",
4329 (void *)map
->pmap
, map
->nentries
, map
->timestamp
);
4332 if (!full
&& db_indent
)
4336 for (entry
= map
->header
.next
; entry
!= &map
->header
;
4337 entry
= entry
->next
) {
4338 db_iprintf("map entry %p: start=%p, end=%p\n",
4339 (void *)entry
, (void *)entry
->start
, (void *)entry
->end
);
4342 static char *inheritance_name
[4] =
4343 {"share", "copy", "none", "donate_copy"};
4345 db_iprintf(" prot=%x/%x/%s",
4347 entry
->max_protection
,
4348 inheritance_name
[(int)(unsigned char)
4349 entry
->inheritance
]);
4350 if (entry
->wired_count
!= 0)
4351 db_printf(", wired");
4353 switch(entry
->maptype
) {
4354 case VM_MAPTYPE_SUBMAP
:
4355 /* XXX no %qd in kernel. Truncate entry->offset. */
4356 db_printf(", share=%p, offset=0x%lx\n",
4357 (void *)entry
->object
.sub_map
,
4358 (long)entry
->offset
);
4360 if ((entry
->prev
== &map
->header
) ||
4361 (entry
->prev
->object
.sub_map
!=
4362 entry
->object
.sub_map
)) {
4364 vm_map_print((db_expr_t
)(intptr_t)
4365 entry
->object
.sub_map
,
4370 case VM_MAPTYPE_NORMAL
:
4371 case VM_MAPTYPE_VPAGETABLE
:
4372 /* XXX no %qd in kernel. Truncate entry->offset. */
4373 db_printf(", object=%p, offset=0x%lx",
4374 (void *)entry
->object
.vm_object
,
4375 (long)entry
->offset
);
4376 if (entry
->eflags
& MAP_ENTRY_COW
)
4377 db_printf(", copy (%s)",
4378 (entry
->eflags
& MAP_ENTRY_NEEDS_COPY
) ? "needed" : "done");
4382 if ((entry
->prev
== &map
->header
) ||
4383 (entry
->prev
->object
.vm_object
!=
4384 entry
->object
.vm_object
)) {
4386 vm_object_print((db_expr_t
)(intptr_t)
4387 entry
->object
.vm_object
,
4393 case VM_MAPTYPE_UKSMAP
:
4394 db_printf(", uksmap=%p, offset=0x%lx",
4395 (void *)entry
->object
.uksmap
,
4396 (long)entry
->offset
);
4397 if (entry
->eflags
& MAP_ENTRY_COW
)
4398 db_printf(", copy (%s)",
4399 (entry
->eflags
& MAP_ENTRY_NEEDS_COPY
) ? "needed" : "done");
4415 DB_SHOW_COMMAND(procvm
, procvm
)
4420 p
= (struct proc
*) addr
;
4425 db_printf("p = %p, vmspace = %p, map = %p, pmap = %p\n",
4426 (void *)p
, (void *)p
->p_vmspace
, (void *)&p
->p_vmspace
->vm_map
,
4427 (void *)vmspace_pmap(p
->p_vmspace
));
4429 vm_map_print((db_expr_t
)(intptr_t)&p
->p_vmspace
->vm_map
, 1, 0, NULL
);