4 * Copyright (c) 1988 University of Utah.
5 * Copyright (c) 1991, 1993
6 * The Regents of the University of California. All rights reserved.
8 * This code is derived from software contributed to Berkeley by
9 * the Systems Programming Group of the University of Utah Computer
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * from: Utah $Hdr: vm_mmap.c 1.6 91/10/21$
38 * @(#)vm_mmap.c 8.4 (Berkeley) 1/12/94
39 * $FreeBSD: src/sys/vm/vm_mmap.c,v 1.108.2.6 2002/07/02 20:06:19 dillon Exp $
43 * Mapped file (mmap) interface to VM
46 #include <sys/param.h>
47 #include <sys/kernel.h>
48 #include <sys/systm.h>
49 #include <sys/sysproto.h>
50 #include <sys/filedesc.h>
51 #include <sys/kern_syscall.h>
54 #include <sys/resource.h>
55 #include <sys/resourcevar.h>
56 #include <sys/vnode.h>
57 #include <sys/fcntl.h>
62 #include <sys/vmmeter.h>
63 #include <sys/sysctl.h>
66 #include <vm/vm_param.h>
69 #include <vm/vm_map.h>
70 #include <vm/vm_object.h>
71 #include <vm/vm_page.h>
72 #include <vm/vm_pager.h>
73 #include <vm/vm_pageout.h>
74 #include <vm/vm_extern.h>
75 #include <vm/vm_kern.h>
77 #include <sys/file2.h>
78 #include <sys/thread.h>
79 #include <sys/thread2.h>
80 #include <vm/vm_page2.h>
82 static int max_proc_mmap
= 1000000;
83 SYSCTL_INT(_vm
, OID_AUTO
, max_proc_mmap
, CTLFLAG_RW
, &max_proc_mmap
, 0, "");
85 SYSCTL_INT(_vm
, OID_AUTO
, vkernel_enable
, CTLFLAG_RW
, &vkernel_enable
, 0, "");
91 sys_sbrk(struct sbrk_args
*uap
)
93 /* Not yet implemented */
103 sys_sstk(struct sstk_args
*uap
)
105 /* Not yet implemented */
110 * mmap_args(void *addr, size_t len, int prot, int flags, int fd,
111 * long pad, off_t pos)
113 * Memory Map (mmap) system call. Note that the file offset
114 * and address are allowed to be NOT page aligned, though if
115 * the MAP_FIXED flag it set, both must have the same remainder
116 * modulo the PAGE_SIZE (POSIX 1003.1b). If the address is not
117 * page-aligned, the actual mapping starts at trunc_page(addr)
118 * and the return value is adjusted up by the page offset.
120 * Generally speaking, only character devices which are themselves
121 * memory-based, such as a video framebuffer, can be mmap'd. Otherwise
122 * there would be no cache coherency between a descriptor and a VM mapping
123 * both to the same character device.
125 * Block devices can be mmap'd no matter what they represent. Cache coherency
126 * is maintained as long as you do not write directly to the underlying
132 kern_mmap(struct vmspace
*vms
, caddr_t uaddr
, size_t ulen
,
133 int uprot
, int uflags
, int fd
, off_t upos
, void **res
)
135 struct thread
*td
= curthread
;
136 struct proc
*p
= td
->td_proc
;
137 struct file
*fp
= NULL
;
141 vm_size_t size
, pageoff
;
142 vm_prot_t prot
, maxprot
;
150 addr
= (vm_offset_t
) uaddr
;
152 prot
= uprot
& VM_PROT_ALL
;
157 * Make sure mapping fits into numeric range etc.
159 * NOTE: We support the full unsigned range for size now.
161 if (((flags
& MAP_ANON
) && (fd
!= -1 || pos
!= 0)))
167 if (flags
& MAP_STACK
) {
170 if ((prot
& (PROT_READ
|PROT_WRITE
)) != (PROT_READ
|PROT_WRITE
))
177 * Virtual page tables cannot be used with MAP_STACK. Apart from
178 * it not making any sense, the aux union is used by both
181 * Because the virtual page table is stored in the backing object
182 * and might be updated by the kernel, the mapping must be R+W.
184 if (flags
& MAP_VPAGETABLE
) {
185 if (vkernel_enable
== 0)
187 if (flags
& MAP_STACK
)
189 if ((prot
& (PROT_READ
|PROT_WRITE
)) != (PROT_READ
|PROT_WRITE
))
194 * Align the file position to a page boundary,
195 * and save its page offset component.
197 pageoff
= (pos
& PAGE_MASK
);
200 /* Adjust size for rounding (on both ends). */
201 size
+= pageoff
; /* low end... */
202 size
= (vm_size_t
) round_page(size
); /* hi end */
203 if (size
< ulen
) /* wrap */
207 * Check for illegal addresses. Watch out for address wrap... Note
208 * that VM_*_ADDRESS are not constants due to casts (argh).
210 if (flags
& (MAP_FIXED
| MAP_TRYFIXED
)) {
212 * The specified address must have the same remainder
213 * as the file offset taken modulo PAGE_SIZE, so it
214 * should be aligned after adjustment by pageoff.
217 if (addr
& PAGE_MASK
)
221 * Address range must be all in user VM space and not wrap.
223 tmpaddr
= addr
+ size
;
226 if (VM_MAX_USER_ADDRESS
> 0 && tmpaddr
> VM_MAX_USER_ADDRESS
)
228 if (VM_MIN_USER_ADDRESS
> 0 && addr
< VM_MIN_USER_ADDRESS
)
232 * Get a hint of where to map. It also provides mmap offset
233 * randomization if enabled.
235 addr
= vm_map_hint(p
, addr
, prot
);
238 if (flags
& MAP_ANON
) {
240 * Mapping blank space is trivial.
243 maxprot
= VM_PROT_ALL
;
246 * Mapping file, get fp for validation. Obtain vnode and make
247 * sure it is of appropriate type.
249 fp
= holdfp(p
->p_fd
, fd
, -1);
252 if (fp
->f_type
!= DTYPE_VNODE
) {
257 * POSIX shared-memory objects are defined to have
258 * kernel persistence, and are not defined to support
259 * read(2)/write(2) -- or even open(2). Thus, we can
260 * use MAP_ASYNC to trade on-disk coherence for speed.
261 * The shm_open(3) library routine turns on the FPOSIXSHM
262 * flag to request this behavior.
264 if (fp
->f_flag
& FPOSIXSHM
)
266 vp
= (struct vnode
*) fp
->f_data
;
269 * Validate the vnode for the operation.
274 * Get the proper underlying object
276 if ((obj
= vp
->v_object
) == NULL
) {
280 KKASSERT((struct vnode
*)obj
->handle
== vp
);
284 * Make sure a device has not been revoked.
285 * Mappability is handled by the device layer.
287 if (vp
->v_rdev
== NULL
) {
294 * Nothing else is mappable.
301 * XXX hack to handle use of /dev/zero to map anon memory (ala
304 if (vp
->v_type
== VCHR
&& iszerodev(vp
->v_rdev
)) {
306 maxprot
= VM_PROT_ALL
;
311 * cdevs does not provide private mappings of any kind.
313 if (vp
->v_type
== VCHR
&&
314 (flags
& (MAP_PRIVATE
|MAP_COPY
))) {
319 * Ensure that file and memory protections are
320 * compatible. Note that we only worry about
321 * writability if mapping is shared; in this case,
322 * current and max prot are dictated by the open file.
323 * XXX use the vnode instead? Problem is: what
324 * credentials do we use for determination? What if
325 * proc does a setuid?
327 maxprot
= VM_PROT_EXECUTE
;
328 if (fp
->f_flag
& FREAD
) {
329 maxprot
|= VM_PROT_READ
;
330 } else if (prot
& PROT_READ
) {
335 * If we are sharing potential changes (either via
336 * MAP_SHARED or via the implicit sharing of character
337 * device mappings), and we are trying to get write
338 * permission although we opened it without asking
339 * for it, bail out. Check for superuser, only if
340 * we're at securelevel < 1, to allow the XIG X server
341 * to continue to work.
343 if ((flags
& MAP_SHARED
) != 0 || vp
->v_type
== VCHR
) {
344 if ((fp
->f_flag
& FWRITE
) != 0) {
346 if ((error
= VOP_GETATTR(vp
, &va
))) {
350 (IMMUTABLE
|APPEND
)) == 0) {
351 maxprot
|= VM_PROT_WRITE
;
352 } else if (prot
& PROT_WRITE
) {
356 } else if ((prot
& PROT_WRITE
) != 0) {
361 maxprot
|= VM_PROT_WRITE
;
367 lwkt_gettoken(&vms
->vm_map
.token
);
370 * Do not allow more then a certain number of vm_map_entry structures
371 * per process. 0 to disable.
373 if (max_proc_mmap
&& vms
->vm_map
.nentries
>= max_proc_mmap
) {
375 lwkt_reltoken(&vms
->vm_map
.token
);
379 error
= vm_mmap(&vms
->vm_map
, &addr
, size
, prot
, maxprot
,
382 *res
= (void *)(addr
+ pageoff
);
384 lwkt_reltoken(&vms
->vm_map
.token
);
393 * mmap system call handler
398 sys_mmap(struct mmap_args
*uap
)
402 error
= kern_mmap(curproc
->p_vmspace
, uap
->addr
, uap
->len
,
403 uap
->prot
, uap
->flags
,
404 uap
->fd
, uap
->pos
, &uap
->sysmsg_resultp
);
410 * msync system call handler
412 * msync_args(void *addr, size_t len, int flags)
417 sys_msync(struct msync_args
*uap
)
419 struct proc
*p
= curproc
;
422 vm_size_t size
, pageoff
;
427 addr
= (vm_offset_t
) uap
->addr
;
431 pageoff
= (addr
& PAGE_MASK
);
434 size
= (vm_size_t
) round_page(size
);
435 if (size
< uap
->len
) /* wrap */
437 tmpaddr
= addr
+ size
; /* workaround gcc4 opt */
438 if (tmpaddr
< addr
) /* wrap */
441 if ((flags
& (MS_ASYNC
|MS_INVALIDATE
)) == (MS_ASYNC
|MS_INVALIDATE
))
444 map
= &p
->p_vmspace
->vm_map
;
447 * map->token serializes extracting the address range for size == 0
448 * msyncs with the vm_map_clean call; if the token were not held
449 * across the two calls, an intervening munmap/mmap pair, for example,
450 * could cause msync to occur on a wrong region.
452 lwkt_gettoken(&map
->token
);
455 * XXX Gak! If size is zero we are supposed to sync "all modified
456 * pages with the region containing addr". Unfortunately, we don't
457 * really keep track of individual mmaps so we approximate by flushing
458 * the range of the map entry containing addr. This can be incorrect
459 * if the region splits or is coalesced with a neighbor.
462 vm_map_entry_t entry
;
464 vm_map_lock_read(map
);
465 rv
= vm_map_lookup_entry(map
, addr
, &entry
);
467 vm_map_unlock_read(map
);
468 rv
= KERN_INVALID_ADDRESS
;
472 size
= entry
->end
- entry
->start
;
473 vm_map_unlock_read(map
);
477 * Clean the pages and interpret the return value.
479 rv
= vm_map_clean(map
, addr
, addr
+ size
, (flags
& MS_ASYNC
) == 0,
480 (flags
& MS_INVALIDATE
) != 0);
482 lwkt_reltoken(&map
->token
);
487 case KERN_INVALID_ADDRESS
:
488 return (EINVAL
); /* Sun returns ENOMEM? */
499 * munmap system call handler
501 * munmap_args(void *addr, size_t len)
506 sys_munmap(struct munmap_args
*uap
)
508 struct proc
*p
= curproc
;
511 vm_size_t size
, pageoff
;
514 addr
= (vm_offset_t
) uap
->addr
;
517 pageoff
= (addr
& PAGE_MASK
);
520 size
= (vm_size_t
) round_page(size
);
521 if (size
< uap
->len
) /* wrap */
523 tmpaddr
= addr
+ size
; /* workaround gcc4 opt */
524 if (tmpaddr
< addr
) /* wrap */
531 * Check for illegal addresses. Watch out for address wrap... Note
532 * that VM_*_ADDRESS are not constants due to casts (argh).
534 if (VM_MAX_USER_ADDRESS
> 0 && tmpaddr
> VM_MAX_USER_ADDRESS
)
536 if (VM_MIN_USER_ADDRESS
> 0 && addr
< VM_MIN_USER_ADDRESS
)
539 map
= &p
->p_vmspace
->vm_map
;
541 /* map->token serializes between the map check and the actual unmap */
542 lwkt_gettoken(&map
->token
);
545 * Make sure entire range is allocated.
547 if (!vm_map_check_protection(map
, addr
, addr
+ size
,
548 VM_PROT_NONE
, FALSE
)) {
549 lwkt_reltoken(&map
->token
);
552 /* returns nothing but KERN_SUCCESS anyway */
553 vm_map_remove(map
, addr
, addr
+ size
);
554 lwkt_reltoken(&map
->token
);
559 * mprotect_args(const void *addr, size_t len, int prot)
564 sys_mprotect(struct mprotect_args
*uap
)
566 struct proc
*p
= curproc
;
569 vm_size_t size
, pageoff
;
573 addr
= (vm_offset_t
) uap
->addr
;
575 prot
= uap
->prot
& VM_PROT_ALL
;
577 pageoff
= (addr
& PAGE_MASK
);
580 size
= (vm_size_t
) round_page(size
);
581 if (size
< uap
->len
) /* wrap */
583 tmpaddr
= addr
+ size
; /* workaround gcc4 opt */
584 if (tmpaddr
< addr
) /* wrap */
587 switch (vm_map_protect(&p
->p_vmspace
->vm_map
, addr
, addr
+ size
,
592 case KERN_PROTECTION_FAILURE
:
603 * minherit system call handler
605 * minherit_args(void *addr, size_t len, int inherit)
610 sys_minherit(struct minherit_args
*uap
)
612 struct proc
*p
= curproc
;
615 vm_size_t size
, pageoff
;
616 vm_inherit_t inherit
;
619 addr
= (vm_offset_t
)uap
->addr
;
621 inherit
= uap
->inherit
;
623 pageoff
= (addr
& PAGE_MASK
);
626 size
= (vm_size_t
) round_page(size
);
627 if (size
< uap
->len
) /* wrap */
629 tmpaddr
= addr
+ size
; /* workaround gcc4 opt */
630 if (tmpaddr
< addr
) /* wrap */
633 switch (vm_map_inherit(&p
->p_vmspace
->vm_map
, addr
,
634 addr
+ size
, inherit
)) {
638 case KERN_PROTECTION_FAILURE
:
649 * madvise system call handler
651 * madvise_args(void *addr, size_t len, int behav)
656 sys_madvise(struct madvise_args
*uap
)
658 struct proc
*p
= curproc
;
659 vm_offset_t start
, end
;
660 vm_offset_t tmpaddr
= (vm_offset_t
)uap
->addr
+ uap
->len
;
664 * Check for illegal behavior
666 if (uap
->behav
< 0 || uap
->behav
>= MADV_CONTROL_END
)
669 * Check for illegal addresses. Watch out for address wrap... Note
670 * that VM_*_ADDRESS are not constants due to casts (argh).
672 if (tmpaddr
< (vm_offset_t
)uap
->addr
)
674 if (VM_MAX_USER_ADDRESS
> 0 && tmpaddr
> VM_MAX_USER_ADDRESS
)
676 if (VM_MIN_USER_ADDRESS
> 0 && uap
->addr
< VM_MIN_USER_ADDRESS
)
680 * Since this routine is only advisory, we default to conservative
683 start
= trunc_page((vm_offset_t
)uap
->addr
);
684 end
= round_page(tmpaddr
);
686 error
= vm_map_madvise(&p
->p_vmspace
->vm_map
, start
, end
,
692 * mcontrol system call handler
694 * mcontrol_args(void *addr, size_t len, int behav, off_t value)
699 sys_mcontrol(struct mcontrol_args
*uap
)
701 struct proc
*p
= curproc
;
702 vm_offset_t start
, end
;
703 vm_offset_t tmpaddr
= (vm_offset_t
)uap
->addr
+ uap
->len
;
707 * Check for illegal behavior
709 if (uap
->behav
< 0 || uap
->behav
> MADV_CONTROL_END
)
712 * Check for illegal addresses. Watch out for address wrap... Note
713 * that VM_*_ADDRESS are not constants due to casts (argh).
715 if (tmpaddr
< (vm_offset_t
) uap
->addr
)
717 if (VM_MAX_USER_ADDRESS
> 0 && tmpaddr
> VM_MAX_USER_ADDRESS
)
719 if (VM_MIN_USER_ADDRESS
> 0 && uap
->addr
< VM_MIN_USER_ADDRESS
)
723 * Since this routine is only advisory, we default to conservative
726 start
= trunc_page((vm_offset_t
)uap
->addr
);
727 end
= round_page(tmpaddr
);
729 error
= vm_map_madvise(&p
->p_vmspace
->vm_map
, start
, end
,
730 uap
->behav
, uap
->value
);
736 * mincore system call handler
738 * mincore_args(const void *addr, size_t len, char *vec)
743 sys_mincore(struct mincore_args
*uap
)
745 struct proc
*p
= curproc
;
746 vm_offset_t addr
, first_addr
;
747 vm_offset_t end
, cend
;
752 int vecindex
, lastvecindex
;
753 vm_map_entry_t current
;
754 vm_map_entry_t entry
;
756 unsigned int timestamp
;
759 * Make sure that the addresses presented are valid for user
762 first_addr
= addr
= trunc_page((vm_offset_t
) uap
->addr
);
763 end
= addr
+ (vm_size_t
)round_page(uap
->len
);
766 if (VM_MAX_USER_ADDRESS
> 0 && end
> VM_MAX_USER_ADDRESS
)
770 * Address of byte vector
774 map
= &p
->p_vmspace
->vm_map
;
775 pmap
= vmspace_pmap(p
->p_vmspace
);
777 lwkt_gettoken(&map
->token
);
778 vm_map_lock_read(map
);
780 timestamp
= map
->timestamp
;
782 if (!vm_map_lookup_entry(map
, addr
, &entry
))
786 * Do this on a map entry basis so that if the pages are not
787 * in the current processes address space, we can easily look
788 * up the pages elsewhere.
792 (current
!= &map
->header
) && (current
->start
< end
);
793 current
= current
->next
) {
796 * ignore submaps (for now) or null objects
798 if (current
->maptype
!= VM_MAPTYPE_NORMAL
&&
799 current
->maptype
!= VM_MAPTYPE_VPAGETABLE
) {
802 if (current
->object
.vm_object
== NULL
)
806 * limit this scan to the current map entry and the
807 * limits for the mincore call
809 if (addr
< current
->start
)
810 addr
= current
->start
;
816 * scan this entry one page at a time
818 while (addr
< cend
) {
820 * Check pmap first, it is likely faster, also
821 * it can provide info as to whether we are the
822 * one referencing or modifying the page.
824 * If we have to check the VM object, only mess
825 * around with normal maps. Do not mess around
826 * with virtual page tables (XXX).
828 mincoreinfo
= pmap_mincore(pmap
, addr
);
829 if (mincoreinfo
== 0 &&
830 current
->maptype
== VM_MAPTYPE_NORMAL
) {
836 * calculate the page index into the object
838 offset
= current
->offset
+ (addr
- current
->start
);
839 pindex
= OFF_TO_IDX(offset
);
842 * if the page is resident, then gather
843 * information about it. spl protection is
844 * required to maintain the object
845 * association. And XXX what if the page is
846 * busy? What's the deal with that?
848 * XXX vm_token - legacy for pmap_ts_referenced
849 * in i386 and vkernel pmap code.
851 lwkt_gettoken(&vm_token
);
852 vm_object_hold(current
->object
.vm_object
);
853 m
= vm_page_lookup(current
->object
.vm_object
,
856 mincoreinfo
= MINCORE_INCORE
;
857 if (m
->dirty
|| pmap_is_modified(m
))
858 mincoreinfo
|= MINCORE_MODIFIED_OTHER
;
859 if ((m
->flags
& PG_REFERENCED
) ||
860 pmap_ts_referenced(m
)) {
861 vm_page_flag_set(m
, PG_REFERENCED
);
862 mincoreinfo
|= MINCORE_REFERENCED_OTHER
;
865 vm_object_drop(current
->object
.vm_object
);
866 lwkt_reltoken(&vm_token
);
870 * subyte may page fault. In case it needs to modify
871 * the map, we release the lock.
873 vm_map_unlock_read(map
);
876 * calculate index into user supplied byte vector
878 vecindex
= OFF_TO_IDX(addr
- first_addr
);
881 * If we have skipped map entries, we need to make sure that
882 * the byte vector is zeroed for those skipped entries.
884 while((lastvecindex
+ 1) < vecindex
) {
885 error
= subyte( vec
+ lastvecindex
, 0);
894 * Pass the page information to the user
896 error
= subyte(vec
+ vecindex
, mincoreinfo
);
903 * If the map has changed, due to the subyte,
904 * the previous output may be invalid.
906 vm_map_lock_read(map
);
907 if (timestamp
!= map
->timestamp
)
910 lastvecindex
= vecindex
;
916 * subyte may page fault. In case it needs to modify
917 * the map, we release the lock.
919 vm_map_unlock_read(map
);
922 * Zero the last entries in the byte vector.
924 vecindex
= OFF_TO_IDX(end
- first_addr
);
925 while((lastvecindex
+ 1) < vecindex
) {
926 error
= subyte( vec
+ lastvecindex
, 0);
935 * If the map has changed, due to the subyte, the previous
936 * output may be invalid.
938 vm_map_lock_read(map
);
939 if (timestamp
!= map
->timestamp
)
941 vm_map_unlock_read(map
);
945 lwkt_reltoken(&map
->token
);
950 * mlock system call handler
952 * mlock_args(const void *addr, size_t len)
957 sys_mlock(struct mlock_args
*uap
)
961 vm_size_t size
, pageoff
;
962 struct thread
*td
= curthread
;
963 struct proc
*p
= td
->td_proc
;
966 addr
= (vm_offset_t
) uap
->addr
;
969 pageoff
= (addr
& PAGE_MASK
);
972 size
= (vm_size_t
) round_page(size
);
973 if (size
< uap
->len
) /* wrap */
975 tmpaddr
= addr
+ size
; /* workaround gcc4 opt */
976 if (tmpaddr
< addr
) /* wrap */
979 if (atop(size
) + vmstats
.v_wire_count
> vm_page_max_wired
)
983 * We do not need to synchronize against other threads updating ucred;
984 * they update p->ucred, which is synchronized into td_ucred ourselves.
986 #ifdef pmap_wired_count
987 if (size
+ ptoa(pmap_wired_count(vm_map_pmap(&p
->p_vmspace
->vm_map
))) >
988 p
->p_rlimit
[RLIMIT_MEMLOCK
].rlim_cur
) {
992 error
= priv_check_cred(td
->td_ucred
, PRIV_ROOT
, 0);
997 error
= vm_map_unwire(&p
->p_vmspace
->vm_map
, addr
, addr
+ size
, FALSE
);
998 return (error
== KERN_SUCCESS
? 0 : ENOMEM
);
1007 sys_mlockall(struct mlockall_args
*uap
)
1009 struct thread
*td
= curthread
;
1010 struct proc
*p
= td
->td_proc
;
1011 vm_map_t map
= &p
->p_vmspace
->vm_map
;
1012 vm_map_entry_t entry
;
1014 int rc
= KERN_SUCCESS
;
1016 if (((how
& MCL_CURRENT
) == 0) && ((how
& MCL_FUTURE
) == 0))
1019 rc
= priv_check_cred(td
->td_ucred
, PRIV_ROOT
, 0);
1025 if (how
& MCL_CURRENT
) {
1026 for(entry
= map
->header
.next
;
1027 entry
!= &map
->header
;
1028 entry
= entry
->next
);
1034 if (how
& MCL_FUTURE
)
1035 map
->flags
|= MAP_WIREFUTURE
;
1045 * Unwire all user-wired map entries, cancel MCL_FUTURE.
1050 sys_munlockall(struct munlockall_args
*uap
)
1052 struct thread
*td
= curthread
;
1053 struct proc
*p
= td
->td_proc
;
1054 vm_map_t map
= &p
->p_vmspace
->vm_map
;
1055 vm_map_entry_t entry
;
1056 int rc
= KERN_SUCCESS
;
1060 /* Clear MAP_WIREFUTURE to cancel mlockall(MCL_FUTURE) */
1061 map
->flags
&= ~MAP_WIREFUTURE
;
1064 for (entry
= map
->header
.next
;
1065 entry
!= &map
->header
;
1066 entry
= entry
->next
) {
1067 if ((entry
->eflags
& MAP_ENTRY_USER_WIRED
) == 0)
1071 * If we encounter an in-transition entry, we release the
1072 * map lock and retry the scan; we do not decrement any
1073 * wired_count more than once because we do not touch
1074 * any entries with MAP_ENTRY_USER_WIRED not set.
1076 * There is a potential interleaving with concurrent
1077 * mlockall()s here -- if we abort a scan, an mlockall()
1078 * could start, wire a number of entries before our
1079 * current position in, and then stall itself on this
1080 * or any other in-transition entry. If that occurs, when
1081 * we resume, we will unwire those entries.
1083 if (entry
->eflags
& MAP_ENTRY_IN_TRANSITION
) {
1084 entry
->eflags
|= MAP_ENTRY_NEEDS_WAKEUP
;
1085 ++mycpu
->gd_cnt
.v_intrans_coll
;
1086 ++mycpu
->gd_cnt
.v_intrans_wait
;
1087 vm_map_transition_wait(map
, 1);
1091 KASSERT(entry
->wired_count
> 0,
1092 ("wired_count was 0 with USER_WIRED set! %p", entry
));
1094 /* Drop wired count, if it hits zero, unwire the entry */
1095 entry
->eflags
&= ~MAP_ENTRY_USER_WIRED
;
1096 entry
->wired_count
--;
1097 if (entry
->wired_count
== 0)
1098 vm_fault_unwire(map
, entry
);
1107 * munlock system call handler
1109 * munlock_args(const void *addr, size_t len)
1114 sys_munlock(struct munlock_args
*uap
)
1116 struct thread
*td
= curthread
;
1117 struct proc
*p
= td
->td_proc
;
1119 vm_offset_t tmpaddr
;
1120 vm_size_t size
, pageoff
;
1123 addr
= (vm_offset_t
) uap
->addr
;
1126 pageoff
= (addr
& PAGE_MASK
);
1129 size
= (vm_size_t
) round_page(size
);
1131 tmpaddr
= addr
+ size
;
1132 if (tmpaddr
< addr
) /* wrap */
1135 #ifndef pmap_wired_count
1136 error
= priv_check(td
, PRIV_ROOT
);
1141 error
= vm_map_unwire(&p
->p_vmspace
->vm_map
, addr
, addr
+ size
, TRUE
);
1142 return (error
== KERN_SUCCESS
? 0 : ENOMEM
);
1146 * Internal version of mmap.
1147 * Currently used by mmap, exec, and sys5 shared memory.
1148 * Handle is either a vnode pointer or NULL for MAP_ANON.
1153 vm_mmap(vm_map_t map
, vm_offset_t
*addr
, vm_size_t size
, vm_prot_t prot
,
1154 vm_prot_t maxprot
, int flags
, void *handle
, vm_ooffset_t foff
)
1161 int (*uksmap
)(cdev_t dev
, vm_page_t fake
);
1163 struct thread
*td
= curthread
;
1165 int rv
= KERN_SUCCESS
;
1173 objsize
= round_page(size
);
1178 lwkt_gettoken(&map
->token
);
1181 * XXX messy code, fixme
1183 * NOTE: Overflow checks require discrete statements or GCC4
1184 * will optimize it out.
1186 if ((p
= curproc
) != NULL
&& map
== &p
->p_vmspace
->vm_map
) {
1187 esize
= map
->size
+ size
; /* workaround gcc4 opt */
1188 if (esize
< map
->size
||
1189 esize
> p
->p_rlimit
[RLIMIT_VMEM
].rlim_cur
) {
1190 lwkt_reltoken(&map
->token
);
1196 * We currently can only deal with page aligned file offsets.
1197 * The check is here rather than in the syscall because the
1198 * kernel calls this function internally for other mmaping
1199 * operations (such as in exec) and non-aligned offsets will
1200 * cause pmap inconsistencies...so we want to be sure to
1201 * disallow this in all cases.
1203 * NOTE: Overflow checks require discrete statements or GCC4
1204 * will optimize it out.
1206 if (foff
& PAGE_MASK
) {
1207 lwkt_reltoken(&map
->token
);
1212 * Handle alignment. For large memory maps it is possible
1213 * that the MMU can optimize the page table so align anything
1214 * that is a multiple of SEG_SIZE to SEG_SIZE.
1216 * Also align any large mapping (bigger than 16x SG_SIZE) to a
1217 * SEG_SIZE address boundary.
1219 if (flags
& MAP_SIZEALIGN
) {
1221 if ((align
^ (align
- 1)) != (align
<< 1) - 1) {
1222 lwkt_reltoken(&map
->token
);
1225 } else if ((flags
& MAP_FIXED
) == 0 &&
1226 ((size
& SEG_MASK
) == 0 || size
> SEG_SIZE
* 16)) {
1232 if ((flags
& (MAP_FIXED
| MAP_TRYFIXED
)) == 0) {
1234 *addr
= round_page(*addr
);
1236 if (*addr
!= trunc_page(*addr
)) {
1237 lwkt_reltoken(&map
->token
);
1240 eaddr
= *addr
+ size
;
1241 if (eaddr
< *addr
) {
1242 lwkt_reltoken(&map
->token
);
1246 if ((flags
& MAP_TRYFIXED
) == 0)
1247 vm_map_remove(map
, *addr
, *addr
+ size
);
1253 * Lookup/allocate object.
1255 if (flags
& MAP_ANON
) {
1257 * Unnamed anonymous regions always start at 0.
1261 * Default memory object
1263 object
= default_pager_alloc(handle
, objsize
,
1265 if (object
== NULL
) {
1266 lwkt_reltoken(&map
->token
);
1269 docow
= MAP_PREFAULT_PARTIAL
;
1272 * Implicit single instance of a default memory
1273 * object, so we don't need a VM object yet.
1281 vp
= (struct vnode
*)handle
;
1284 * Non-anonymous mappings of VCHR (aka not /dev/zero)
1285 * cannot specify MAP_STACK or MAP_VPAGETABLE.
1287 if (vp
->v_type
== VCHR
) {
1288 if (flags
& (MAP_STACK
| MAP_VPAGETABLE
)) {
1289 lwkt_reltoken(&map
->token
);
1294 if (vp
->v_type
== VCHR
&& vp
->v_rdev
->si_ops
->d_uksmap
) {
1296 * Device mappings without a VM object, typically
1297 * sharing permanently allocated kernel memory or
1298 * process-context-specific (per-process) data.
1300 * Force them to be shared.
1302 uksmap
= vp
->v_rdev
->si_ops
->d_uksmap
;
1304 docow
= MAP_PREFAULT_PARTIAL
;
1305 flags
&= ~(MAP_PRIVATE
|MAP_COPY
);
1306 flags
|= MAP_SHARED
;
1307 } else if (vp
->v_type
== VCHR
) {
1309 * Device mappings (device size unknown?).
1310 * Force them to be shared.
1312 error
= dev_dmmap_single(vp
->v_rdev
, &foff
, objsize
,
1313 &object
, prot
, NULL
);
1315 if (error
== ENODEV
) {
1316 handle
= (void *)(intptr_t)vp
->v_rdev
;
1317 object
= dev_pager_alloc(handle
, objsize
, prot
, foff
);
1318 if (object
== NULL
) {
1319 lwkt_reltoken(&map
->token
);
1323 lwkt_reltoken(&map
->token
);
1327 docow
= MAP_PREFAULT_PARTIAL
;
1328 flags
&= ~(MAP_PRIVATE
|MAP_COPY
);
1329 flags
|= MAP_SHARED
;
1332 * Regular file mapping (typically). The attribute
1333 * check is for the link count test only. mmapable
1334 * vnodes must already have a VM object assigned.
1339 error
= VOP_GETATTR(vp
, &vat
);
1341 lwkt_reltoken(&map
->token
);
1344 docow
= MAP_PREFAULT_PARTIAL
;
1345 object
= vnode_pager_reference(vp
);
1346 if (object
== NULL
&& vp
->v_type
== VREG
) {
1347 lwkt_reltoken(&map
->token
);
1348 kprintf("Warning: cannot mmap vnode %p, no "
1354 * If it is a regular file without any references
1355 * we do not need to sync it.
1357 if (vp
->v_type
== VREG
&& vat
.va_nlink
== 0) {
1358 flags
|= MAP_NOSYNC
;
1364 * Deal with the adjusted flags
1366 if ((flags
& (MAP_ANON
|MAP_SHARED
)) == 0)
1367 docow
|= MAP_COPY_ON_WRITE
;
1368 if (flags
& MAP_NOSYNC
)
1369 docow
|= MAP_DISABLE_SYNCER
;
1370 if (flags
& MAP_NOCORE
)
1371 docow
|= MAP_DISABLE_COREDUMP
;
1374 * This may place the area in its own page directory if (size) is
1375 * large enough, otherwise it typically returns its argument.
1377 * (object can be NULL)
1380 *addr
= pmap_addr_hint(object
, *addr
, size
);
1384 * Stack mappings need special attention.
1386 * Mappings that use virtual page tables will default to storing
1387 * the page table at offset 0.
1390 rv
= vm_map_find(map
, uksmap
, vp
->v_rdev
,
1393 VM_MAPTYPE_UKSMAP
, VM_SUBSYS_MMAP
,
1394 prot
, maxprot
, docow
);
1395 } else if (flags
& MAP_STACK
) {
1396 rv
= vm_map_stack(map
, *addr
, size
, flags
,
1397 prot
, maxprot
, docow
);
1398 } else if (flags
& MAP_VPAGETABLE
) {
1399 rv
= vm_map_find(map
, object
, NULL
,
1402 VM_MAPTYPE_VPAGETABLE
, VM_SUBSYS_MMAP
,
1403 prot
, maxprot
, docow
);
1405 rv
= vm_map_find(map
, object
, NULL
,
1408 VM_MAPTYPE_NORMAL
, VM_SUBSYS_MMAP
,
1409 prot
, maxprot
, docow
);
1412 if (rv
!= KERN_SUCCESS
) {
1414 * Lose the object reference. Will destroy the
1415 * object if it's an unnamed anonymous mapping
1416 * or named anonymous without other references.
1418 * (NOTE: object can be NULL)
1420 vm_object_deallocate(object
);
1425 * Shared memory is also shared with children.
1427 if (flags
& (MAP_SHARED
|MAP_INHERIT
)) {
1428 rv
= vm_map_inherit(map
, *addr
, *addr
+ size
, VM_INHERIT_SHARE
);
1429 if (rv
!= KERN_SUCCESS
) {
1430 vm_map_remove(map
, *addr
, *addr
+ size
);
1435 /* If a process has marked all future mappings for wiring, do so */
1436 if ((rv
== KERN_SUCCESS
) && (map
->flags
& MAP_WIREFUTURE
))
1437 vm_map_unwire(map
, *addr
, *addr
+ size
, FALSE
);
1440 * Set the access time on the vnode
1443 vn_mark_atime(vp
, td
);
1445 lwkt_reltoken(&map
->token
);
1450 case KERN_INVALID_ADDRESS
:
1453 case KERN_PROTECTION_FAILURE
:
1461 * Translate a Mach VM return code to zero on success or the appropriate errno
1465 vm_mmap_to_errno(int rv
)
1471 case KERN_INVALID_ADDRESS
:
1474 case KERN_PROTECTION_FAILURE
: