xref: /freebsd/sys/vm/vm_mmap.c (revision ce834215a70ff69e7e222827437116eee2f9ac6f)
1 /*
2  * Copyright (c) 1988 University of Utah.
3  * Copyright (c) 1991, 1993
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * the Systems Programming Group of the University of Utah Computer
8  * Science Department.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  * from: Utah $Hdr: vm_mmap.c 1.6 91/10/21$
39  *
40  *	@(#)vm_mmap.c	8.4 (Berkeley) 1/12/94
41  * $Id: vm_mmap.c,v 1.63 1997/03/23 03:37:53 bde Exp $
42  */
43 
44 /*
45  * Mapped file (mmap) interface to VM
46  */
47 
48 #include "opt_rlimit.h"
49 
50 #include <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/sysproto.h>
53 #include <sys/filedesc.h>
54 #include <sys/resourcevar.h>
55 #include <sys/proc.h>
56 #include <sys/vnode.h>
57 #include <sys/fcntl.h>
58 #include <sys/file.h>
59 #include <sys/mman.h>
60 #include <sys/conf.h>
61 #include <sys/vmmeter.h>
62 
63 #include <miscfs/specfs/specdev.h>
64 
65 #include <vm/vm.h>
66 #include <vm/vm_param.h>
67 #include <vm/vm_prot.h>
68 #include <vm/vm_inherit.h>
69 #include <sys/lock.h>
70 #include <vm/pmap.h>
71 #include <vm/vm_map.h>
72 #include <vm/vm_object.h>
73 #include <vm/vm_pager.h>
74 #include <vm/vm_pageout.h>
75 #include <vm/vm_extern.h>
76 #include <vm/vm_kern.h>
77 #include <vm/vm_page.h>
78 
79 #ifndef _SYS_SYSPROTO_H_
80 struct sbrk_args {
81 	int incr;
82 };
83 #endif
84 
85 /* ARGSUSED */
86 int
87 sbrk(p, uap, retval)
88 	struct proc *p;
89 	struct sbrk_args *uap;
90 	int *retval;
91 {
92 
93 	/* Not yet implemented */
94 	return (EOPNOTSUPP);
95 }
96 
97 #ifndef _SYS_SYSPROTO_H_
98 struct sstk_args {
99 	int incr;
100 };
101 #endif
102 
103 /* ARGSUSED */
104 int
105 sstk(p, uap, retval)
106 	struct proc *p;
107 	struct sstk_args *uap;
108 	int *retval;
109 {
110 
111 	/* Not yet implemented */
112 	return (EOPNOTSUPP);
113 }
114 
115 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
116 #ifndef _SYS_SYSPROTO_H_
117 struct getpagesize_args {
118 	int dummy;
119 };
120 #endif
121 
122 /* ARGSUSED */
123 int
124 ogetpagesize(p, uap, retval)
125 	struct proc *p;
126 	struct getpagesize_args *uap;
127 	int *retval;
128 {
129 
130 	*retval = PAGE_SIZE;
131 	return (0);
132 }
133 #endif				/* COMPAT_43 || COMPAT_SUNOS */
134 
135 #ifndef _SYS_SYSPROTO_H_
136 struct mmap_args {
137 	caddr_t addr;
138 	size_t len;
139 	int prot;
140 	int flags;
141 	int fd;
142 	long pad;
143 	off_t pos;
144 };
145 #endif
146 
147 int
148 mmap(p, uap, retval)
149 	struct proc *p;
150 	register struct mmap_args *uap;
151 	int *retval;
152 {
153 	register struct filedesc *fdp = p->p_fd;
154 	register struct file *fp;
155 	struct vnode *vp;
156 	vm_offset_t addr;
157 	vm_size_t size, pageoff;
158 	vm_prot_t prot, maxprot;
159 	caddr_t handle;
160 	int flags, error;
161 
162 	prot = uap->prot & VM_PROT_ALL;
163 	flags = uap->flags;
164 	/*
165 	 * Address (if FIXED) must be page aligned. Size is implicitly rounded
166 	 * to a page boundary.
167 	 */
168 	addr = (vm_offset_t) uap->addr;
169 	if (((flags & MAP_FIXED) && (addr & PAGE_MASK)) ||
170 	    (ssize_t) uap->len < 0 || ((flags & MAP_ANON) && uap->fd != -1))
171 		return (EINVAL);
172 
173 	/*
174 	 * Round page if not already disallowed by above test
175 	 * XXX: Is there any point in the MAP_FIXED align requirement above?
176 	 */
177 	size = uap->len;
178 	pageoff = (addr & PAGE_MASK);
179 	addr -= pageoff;
180 	size += pageoff;
181 	size = (vm_size_t) round_page(size);
182 
183 	/*
184 	 * Check for illegal addresses.  Watch out for address wrap... Note
185 	 * that VM_*_ADDRESS are not constants due to casts (argh).
186 	 */
187 	if (flags & MAP_FIXED) {
188 		if (VM_MAXUSER_ADDRESS > 0 && addr + size > VM_MAXUSER_ADDRESS)
189 			return (EINVAL);
190 #ifndef i386
191 		if (VM_MIN_ADDRESS > 0 && addr < VM_MIN_ADDRESS)
192 			return (EINVAL);
193 #endif
194 		if (addr + size < addr)
195 			return (EINVAL);
196 	}
197 	/*
198 	 * XXX if no hint provided for a non-fixed mapping place it after the
199 	 * end of the largest possible heap.
200 	 *
201 	 * There should really be a pmap call to determine a reasonable location.
202 	 */
203 	if (addr == 0 && (flags & MAP_FIXED) == 0)
204 		addr = round_page(p->p_vmspace->vm_daddr + MAXDSIZ);
205 	if (flags & MAP_ANON) {
206 		/*
207 		 * Mapping blank space is trivial.
208 		 */
209 		handle = NULL;
210 		maxprot = VM_PROT_ALL;
211 	} else {
212 		/*
213 		 * Mapping file, get fp for validation. Obtain vnode and make
214 		 * sure it is of appropriate type.
215 		 */
216 		if (((unsigned) uap->fd) >= fdp->fd_nfiles ||
217 		    (fp = fdp->fd_ofiles[uap->fd]) == NULL)
218 			return (EBADF);
219 		if (fp->f_type != DTYPE_VNODE)
220 			return (EINVAL);
221 		vp = (struct vnode *) fp->f_data;
222 		if (vp->v_type != VREG && vp->v_type != VCHR)
223 			return (EINVAL);
224 		/*
225 		 * XXX hack to handle use of /dev/zero to map anon memory (ala
226 		 * SunOS).
227 		 */
228 		if (vp->v_type == VCHR && iszerodev(vp->v_rdev)) {
229 			handle = NULL;
230 			maxprot = VM_PROT_ALL;
231 			flags |= MAP_ANON;
232 		} else {
233 			/*
234 			 * Ensure that file and memory protections are
235 			 * compatible.  Note that we only worry about
236 			 * writability if mapping is shared; in this case,
237 			 * current and max prot are dictated by the open file.
238 			 * XXX use the vnode instead?  Problem is: what
239 			 * credentials do we use for determination? What if
240 			 * proc does a setuid?
241 			 */
242 			maxprot = VM_PROT_EXECUTE;	/* ??? */
243 			if (fp->f_flag & FREAD)
244 				maxprot |= VM_PROT_READ;
245 			else if (prot & PROT_READ)
246 				return (EACCES);
247 			if (flags & MAP_SHARED) {
248 				if (fp->f_flag & FWRITE)
249 					maxprot |= VM_PROT_WRITE;
250 				else if (prot & PROT_WRITE)
251 					return (EACCES);
252 			} else
253 				maxprot |= VM_PROT_WRITE;
254 			handle = (caddr_t) vp;
255 		}
256 	}
257 	error = vm_mmap(&p->p_vmspace->vm_map, &addr, size, prot, maxprot,
258 	    flags, handle, uap->pos);
259 	if (error == 0)
260 		*retval = (int) addr;
261 	return (error);
262 }
263 
264 #ifdef COMPAT_43
265 #ifndef _SYS_SYSPROTO_H_
266 struct ommap_args {
267 	caddr_t addr;
268 	int len;
269 	int prot;
270 	int flags;
271 	int fd;
272 	long pos;
273 };
274 #endif
275 int
276 ommap(p, uap, retval)
277 	struct proc *p;
278 	register struct ommap_args *uap;
279 	int *retval;
280 {
281 	struct mmap_args nargs;
282 	static const char cvtbsdprot[8] = {
283 		0,
284 		PROT_EXEC,
285 		PROT_WRITE,
286 		PROT_EXEC | PROT_WRITE,
287 		PROT_READ,
288 		PROT_EXEC | PROT_READ,
289 		PROT_WRITE | PROT_READ,
290 		PROT_EXEC | PROT_WRITE | PROT_READ,
291 	};
292 
293 #define	OMAP_ANON	0x0002
294 #define	OMAP_COPY	0x0020
295 #define	OMAP_SHARED	0x0010
296 #define	OMAP_FIXED	0x0100
297 #define	OMAP_INHERIT	0x0800
298 
299 	nargs.addr = uap->addr;
300 	nargs.len = uap->len;
301 	nargs.prot = cvtbsdprot[uap->prot & 0x7];
302 	nargs.flags = 0;
303 	if (uap->flags & OMAP_ANON)
304 		nargs.flags |= MAP_ANON;
305 	if (uap->flags & OMAP_COPY)
306 		nargs.flags |= MAP_COPY;
307 	if (uap->flags & OMAP_SHARED)
308 		nargs.flags |= MAP_SHARED;
309 	else
310 		nargs.flags |= MAP_PRIVATE;
311 	if (uap->flags & OMAP_FIXED)
312 		nargs.flags |= MAP_FIXED;
313 	if (uap->flags & OMAP_INHERIT)
314 		nargs.flags |= MAP_INHERIT;
315 	nargs.fd = uap->fd;
316 	nargs.pos = uap->pos;
317 	return (mmap(p, &nargs, retval));
318 }
319 #endif				/* COMPAT_43 */
320 
321 
322 #ifndef _SYS_SYSPROTO_H_
323 struct msync_args {
324 	caddr_t addr;
325 	int len;
326 	int flags;
327 };
328 #endif
329 int
330 msync(p, uap, retval)
331 	struct proc *p;
332 	struct msync_args *uap;
333 	int *retval;
334 {
335 	vm_offset_t addr;
336 	vm_size_t size, pageoff;
337 	int flags;
338 	vm_map_t map;
339 	int rv;
340 
341 	addr = (vm_offset_t) uap->addr;
342 	size = uap->len;
343 	flags = uap->flags;
344 
345 	pageoff = (addr & PAGE_MASK);
346 	addr -= pageoff;
347 	size += pageoff;
348 	size = (vm_size_t) round_page(size);
349 	if (addr + size < addr)
350 		return(EINVAL);
351 
352 	if ((flags & (MS_ASYNC|MS_INVALIDATE)) == (MS_ASYNC|MS_INVALIDATE))
353 		return (EINVAL);
354 
355 	map = &p->p_vmspace->vm_map;
356 
357 	/*
358 	 * XXX Gak!  If size is zero we are supposed to sync "all modified
359 	 * pages with the region containing addr".  Unfortunately, we don't
360 	 * really keep track of individual mmaps so we approximate by flushing
361 	 * the range of the map entry containing addr. This can be incorrect
362 	 * if the region splits or is coalesced with a neighbor.
363 	 */
364 	if (size == 0) {
365 		vm_map_entry_t entry;
366 
367 		vm_map_lock_read(map);
368 		rv = vm_map_lookup_entry(map, addr, &entry);
369 		vm_map_unlock_read(map);
370 		if (rv == FALSE)
371 			return (EINVAL);
372 		addr = entry->start;
373 		size = entry->end - entry->start;
374 	}
375 
376 	/*
377 	 * Clean the pages and interpret the return value.
378 	 */
379 	rv = vm_map_clean(map, addr, addr + size, (flags & MS_ASYNC) == 0,
380 	    (flags & MS_INVALIDATE) != 0);
381 
382 	switch (rv) {
383 	case KERN_SUCCESS:
384 		break;
385 	case KERN_INVALID_ADDRESS:
386 		return (EINVAL);	/* Sun returns ENOMEM? */
387 	case KERN_FAILURE:
388 		return (EIO);
389 	default:
390 		return (EINVAL);
391 	}
392 
393 	return (0);
394 }
395 
396 #ifndef _SYS_SYSPROTO_H_
397 struct munmap_args {
398 	caddr_t addr;
399 	size_t len;
400 };
401 #endif
402 int
403 munmap(p, uap, retval)
404 	register struct proc *p;
405 	register struct munmap_args *uap;
406 	int *retval;
407 {
408 	vm_offset_t addr;
409 	vm_size_t size, pageoff;
410 	vm_map_t map;
411 
412 	addr = (vm_offset_t) uap->addr;
413 	size = uap->len;
414 
415 	pageoff = (addr & PAGE_MASK);
416 	addr -= pageoff;
417 	size += pageoff;
418 	size = (vm_size_t) round_page(size);
419 	if (addr + size < addr)
420 		return(EINVAL);
421 
422 	if (size == 0)
423 		return (0);
424 
425 	/*
426 	 * Check for illegal addresses.  Watch out for address wrap... Note
427 	 * that VM_*_ADDRESS are not constants due to casts (argh).
428 	 */
429 	if (VM_MAXUSER_ADDRESS > 0 && addr + size > VM_MAXUSER_ADDRESS)
430 		return (EINVAL);
431 #ifndef i386
432 	if (VM_MIN_ADDRESS > 0 && addr < VM_MIN_ADDRESS)
433 		return (EINVAL);
434 #endif
435 	if (addr + size < addr)
436 		return (EINVAL);
437 	map = &p->p_vmspace->vm_map;
438 	/*
439 	 * Make sure entire range is allocated.
440 	 */
441 	if (!vm_map_check_protection(map, addr, addr + size, VM_PROT_NONE))
442 		return (EINVAL);
443 	/* returns nothing but KERN_SUCCESS anyway */
444 	(void) vm_map_remove(map, addr, addr + size);
445 	return (0);
446 }
447 
448 void
449 munmapfd(p, fd)
450 	struct proc *p;
451 	int fd;
452 {
453 	/*
454 	 * XXX should unmap any regions mapped to this file
455 	 */
456 	p->p_fd->fd_ofileflags[fd] &= ~UF_MAPPED;
457 }
458 
459 #ifndef _SYS_SYSPROTO_H_
460 struct mprotect_args {
461 	caddr_t addr;
462 	size_t len;
463 	int prot;
464 };
465 #endif
466 int
467 mprotect(p, uap, retval)
468 	struct proc *p;
469 	struct mprotect_args *uap;
470 	int *retval;
471 {
472 	vm_offset_t addr;
473 	vm_size_t size, pageoff;
474 	register vm_prot_t prot;
475 
476 	addr = (vm_offset_t) uap->addr;
477 	size = uap->len;
478 	prot = uap->prot & VM_PROT_ALL;
479 #if defined(VM_PROT_READ_IS_EXEC)
480 	if (prot & VM_PROT_READ)
481 		prot |= VM_PROT_EXECUTE;
482 #endif
483 
484 	pageoff = (addr & PAGE_MASK);
485 	addr -= pageoff;
486 	size += pageoff;
487 	size = (vm_size_t) round_page(size);
488 	if (addr + size < addr)
489 		return(EINVAL);
490 
491 	switch (vm_map_protect(&p->p_vmspace->vm_map, addr, addr + size, prot,
492 		FALSE)) {
493 	case KERN_SUCCESS:
494 		return (0);
495 	case KERN_PROTECTION_FAILURE:
496 		return (EACCES);
497 	}
498 	return (EINVAL);
499 }
500 
501 #ifndef _SYS_SYSPROTO_H_
502 struct minherit_args {
503 	caddr_t addr;
504 	size_t len;
505 	int inherit;
506 };
507 #endif
508 int
509 minherit(p, uap, retval)
510 	struct proc *p;
511 	struct minherit_args *uap;
512 	int *retval;
513 {
514 	vm_offset_t addr;
515 	vm_size_t size, pageoff;
516 	register vm_inherit_t inherit;
517 
518 	addr = (vm_offset_t)uap->addr;
519 	size = uap->len;
520 	inherit = uap->inherit;
521 
522 	pageoff = (addr & PAGE_MASK);
523 	addr -= pageoff;
524 	size += pageoff;
525 	size = (vm_size_t) round_page(size);
526 	if (addr + size < addr)
527 		return(EINVAL);
528 
529 	switch (vm_map_inherit(&p->p_vmspace->vm_map, addr, addr+size,
530 	    inherit)) {
531 	case KERN_SUCCESS:
532 		return (0);
533 	case KERN_PROTECTION_FAILURE:
534 		return (EACCES);
535 	}
536 	return (EINVAL);
537 }
538 
539 #ifndef _SYS_SYSPROTO_H_
540 struct madvise_args {
541 	caddr_t addr;
542 	size_t len;
543 	int behav;
544 };
545 #endif
546 
547 /* ARGSUSED */
548 int
549 madvise(p, uap, retval)
550 	struct proc *p;
551 	struct madvise_args *uap;
552 	int *retval;
553 {
554 	vm_map_t map;
555 	pmap_t pmap;
556 	vm_offset_t start, end;
557 	/*
558 	 * Check for illegal addresses.  Watch out for address wrap... Note
559 	 * that VM_*_ADDRESS are not constants due to casts (argh).
560 	 */
561 	if (VM_MAXUSER_ADDRESS > 0 &&
562 		((vm_offset_t) uap->addr + uap->len) > VM_MAXUSER_ADDRESS)
563 		return (EINVAL);
564 #ifndef i386
565 	if (VM_MIN_ADDRESS > 0 && uap->addr < VM_MIN_ADDRESS)
566 		return (EINVAL);
567 #endif
568 	if (((vm_offset_t) uap->addr + uap->len) < (vm_offset_t) uap->addr)
569 		return (EINVAL);
570 
571 	/*
572 	 * Since this routine is only advisory, we default to conservative
573 	 * behavior.
574 	 */
575 	start = trunc_page((vm_offset_t) uap->addr);
576 	end = round_page((vm_offset_t) uap->addr + uap->len);
577 
578 	map = &p->p_vmspace->vm_map;
579 	pmap = &p->p_vmspace->vm_pmap;
580 
581 	vm_map_madvise(map, pmap, start, end, uap->behav);
582 
583 	return (0);
584 }
585 
586 #ifndef _SYS_SYSPROTO_H_
587 struct mincore_args {
588 	caddr_t addr;
589 	size_t len;
590 	char *vec;
591 };
592 #endif
593 
594 /* ARGSUSED */
595 int
596 mincore(p, uap, retval)
597 	struct proc *p;
598 	struct mincore_args *uap;
599 	int *retval;
600 {
601 	vm_offset_t addr, first_addr;
602 	vm_offset_t end, cend;
603 	pmap_t pmap;
604 	vm_map_t map;
605 	char *vec;
606 	int error;
607 	int vecindex, lastvecindex;
608 	register vm_map_entry_t current;
609 	vm_map_entry_t entry;
610 	int mincoreinfo;
611 
612 	/*
613 	 * Make sure that the addresses presented are valid for user
614 	 * mode.
615 	 */
616 	first_addr = addr = trunc_page((vm_offset_t) uap->addr);
617 	end = addr + (vm_size_t)round_page(uap->len);
618 	if (VM_MAXUSER_ADDRESS > 0 && end > VM_MAXUSER_ADDRESS)
619 		return (EINVAL);
620 	if (end < addr)
621 		return (EINVAL);
622 
623 	/*
624 	 * Address of byte vector
625 	 */
626 	vec = uap->vec;
627 
628 	map = &p->p_vmspace->vm_map;
629 	pmap = &p->p_vmspace->vm_pmap;
630 
631 	vm_map_lock(map);
632 
633 	/*
634 	 * Not needed here
635 	 */
636 #if 0
637 	VM_MAP_RANGE_CHECK(map, addr, end);
638 #endif
639 
640 	if (!vm_map_lookup_entry(map, addr, &entry))
641 		entry = entry->next;
642 
643 	/*
644 	 * Do this on a map entry basis so that if the pages are not
645 	 * in the current processes address space, we can easily look
646 	 * up the pages elsewhere.
647 	 */
648 	lastvecindex = -1;
649 	for(current = entry;
650 		(current != &map->header) && (current->start < end);
651 		current = current->next) {
652 
653 		/*
654 		 * ignore submaps (for now) or null objects
655 		 */
656 		if ((current->eflags & (MAP_ENTRY_IS_A_MAP|MAP_ENTRY_IS_SUB_MAP)) ||
657 			current->object.vm_object == NULL)
658 			continue;
659 
660 		/*
661 		 * limit this scan to the current map entry and the
662 		 * limits for the mincore call
663 		 */
664 		if (addr < current->start)
665 			addr = current->start;
666 		cend = current->end;
667 		if (cend > end)
668 			cend = end;
669 
670 		/*
671 		 * scan this entry one page at a time
672 		 */
673 		while(addr < cend) {
674 			/*
675 			 * Check pmap first, it is likely faster, also
676 			 * it can provide info as to whether we are the
677 			 * one referencing or modifying the page.
678 			 */
679 			mincoreinfo = pmap_mincore(pmap, addr);
680 			if (!mincoreinfo) {
681 				vm_pindex_t pindex;
682 				vm_ooffset_t offset;
683 				vm_page_t m;
684 				/*
685 				 * calculate the page index into the object
686 				 */
687 				offset = current->offset + (addr - current->start);
688 				pindex = OFF_TO_IDX(offset);
689 				m = vm_page_lookup(current->object.vm_object,
690 					pindex);
691 				/*
692 				 * if the page is resident, then gather information about
693 				 * it.
694 				 */
695 				if (m) {
696 					mincoreinfo = MINCORE_INCORE;
697 					if (m->dirty ||
698 						pmap_is_modified(VM_PAGE_TO_PHYS(m)))
699 						mincoreinfo |= MINCORE_MODIFIED_OTHER;
700 					if ((m->flags & PG_REFERENCED) ||
701 						pmap_ts_referenced(VM_PAGE_TO_PHYS(m))) {
702 						m->flags |= PG_REFERENCED;
703 						mincoreinfo |= MINCORE_REFERENCED_OTHER;
704 					}
705 				}
706 			}
707 
708 			/*
709 			 * calculate index into user supplied byte vector
710 			 */
711 			vecindex = OFF_TO_IDX(addr - first_addr);
712 
713 			/*
714 			 * If we have skipped map entries, we need to make sure that
715 			 * the byte vector is zeroed for those skipped entries.
716 			 */
717 			while((lastvecindex + 1) < vecindex) {
718 				error = subyte( vec + lastvecindex, 0);
719 				if (error) {
720 					vm_map_unlock(map);
721 					return (EFAULT);
722 				}
723 				++lastvecindex;
724 			}
725 
726 			/*
727 			 * Pass the page information to the user
728 			 */
729 			error = subyte( vec + vecindex, mincoreinfo);
730 			if (error) {
731 				vm_map_unlock(map);
732 				return (EFAULT);
733 			}
734 			lastvecindex = vecindex;
735 			addr += PAGE_SIZE;
736 		}
737 	}
738 
739 	/*
740 	 * Zero the last entries in the byte vector.
741 	 */
742 	vecindex = OFF_TO_IDX(end - first_addr);
743 	while((lastvecindex + 1) < vecindex) {
744 		error = subyte( vec + lastvecindex, 0);
745 		if (error) {
746 			vm_map_unlock(map);
747 			return (EFAULT);
748 		}
749 		++lastvecindex;
750 	}
751 
752 	vm_map_unlock(map);
753 	return (0);
754 }
755 
756 #ifndef _SYS_SYSPROTO_H_
757 struct mlock_args {
758 	caddr_t addr;
759 	size_t len;
760 };
761 #endif
762 int
763 mlock(p, uap, retval)
764 	struct proc *p;
765 	struct mlock_args *uap;
766 	int *retval;
767 {
768 	vm_offset_t addr;
769 	vm_size_t size, pageoff;
770 	int error;
771 
772 	addr = (vm_offset_t) uap->addr;
773 	size = uap->len;
774 
775 	pageoff = (addr & PAGE_MASK);
776 	addr -= pageoff;
777 	size += pageoff;
778 	size = (vm_size_t) round_page(size);
779 
780 	/* disable wrap around */
781 	if (addr + size < addr)
782 		return (EINVAL);
783 
784 	if (atop(size) + cnt.v_wire_count > vm_page_max_wired)
785 		return (EAGAIN);
786 
787 #ifdef pmap_wired_count
788 	if (size + ptoa(pmap_wired_count(vm_map_pmap(&p->p_vmspace->vm_map))) >
789 	    p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur)
790 		return (ENOMEM);
791 #else
792 	error = suser(p->p_ucred, &p->p_acflag);
793 	if (error)
794 		return (error);
795 #endif
796 
797 	error = vm_map_user_pageable(&p->p_vmspace->vm_map, addr, addr + size, FALSE);
798 	return (error == KERN_SUCCESS ? 0 : ENOMEM);
799 }
800 
801 #ifndef _SYS_SYSPROTO_H_
802 struct mlockall_args {
803 	int	how;
804 };
805 #endif
806 
807 int
808 mlockall(p, uap, retval)
809 	struct proc *p;
810 	struct mlockall_args *uap;
811 	int *retval;
812 {
813 	return 0;
814 }
815 
816 #ifndef _SYS_SYSPROTO_H_
817 struct mlockall_args {
818 	int	how;
819 };
820 #endif
821 
822 int
823 munlockall(p, uap, retval)
824 	struct proc *p;
825 	struct munlockall_args *uap;
826 	int *retval;
827 {
828 	return 0;
829 }
830 
831 #ifndef _SYS_SYSPROTO_H_
832 struct munlock_args {
833 	caddr_t addr;
834 	size_t len;
835 };
836 #endif
837 int
838 munlock(p, uap, retval)
839 	struct proc *p;
840 	struct munlock_args *uap;
841 	int *retval;
842 {
843 	vm_offset_t addr;
844 	vm_size_t size, pageoff;
845 	int error;
846 
847 	addr = (vm_offset_t) uap->addr;
848 	size = uap->len;
849 
850 	pageoff = (addr & PAGE_MASK);
851 	addr -= pageoff;
852 	size += pageoff;
853 	size = (vm_size_t) round_page(size);
854 
855 	/* disable wrap around */
856 	if (addr + size < addr)
857 		return (EINVAL);
858 
859 #ifndef pmap_wired_count
860 	error = suser(p->p_ucred, &p->p_acflag);
861 	if (error)
862 		return (error);
863 #endif
864 
865 	error = vm_map_user_pageable(&p->p_vmspace->vm_map, addr, addr + size, TRUE);
866 	return (error == KERN_SUCCESS ? 0 : ENOMEM);
867 }
868 
869 /*
870  * Internal version of mmap.
871  * Currently used by mmap, exec, and sys5 shared memory.
872  * Handle is either a vnode pointer or NULL for MAP_ANON.
873  */
874 int
875 vm_mmap(map, addr, size, prot, maxprot, flags, handle, foff)
876 	register vm_map_t map;
877 	register vm_offset_t *addr;
878 	register vm_size_t size;
879 	vm_prot_t prot, maxprot;
880 	register int flags;
881 	caddr_t handle;		/* XXX should be vp */
882 	vm_ooffset_t foff;
883 {
884 	boolean_t fitit;
885 	vm_object_t object;
886 	struct vnode *vp = NULL;
887 	objtype_t type;
888 	int rv = KERN_SUCCESS;
889 	vm_ooffset_t objsize;
890 	int docow;
891 	struct proc *p = curproc;
892 
893 	if (size == 0)
894 		return (0);
895 
896 	objsize = size = round_page(size);
897 
898 	/*
899 	 * We currently can only deal with page aligned file offsets.
900 	 * The check is here rather than in the syscall because the
901 	 * kernel calls this function internally for other mmaping
902 	 * operations (such as in exec) and non-aligned offsets will
903 	 * cause pmap inconsistencies...so we want to be sure to
904 	 * disallow this in all cases.
905 	 */
906 	if (foff & PAGE_MASK)
907 		return (EINVAL);
908 
909 	if ((flags & MAP_FIXED) == 0) {
910 		fitit = TRUE;
911 		*addr = round_page(*addr);
912 	} else {
913 		if (*addr != trunc_page(*addr))
914 			return (EINVAL);
915 		fitit = FALSE;
916 		(void) vm_map_remove(map, *addr, *addr + size);
917 	}
918 
919 	/*
920 	 * Lookup/allocate object.
921 	 */
922 	if (flags & MAP_ANON) {
923 		type = OBJT_DEFAULT;
924 		/*
925 		 * Unnamed anonymous regions always start at 0.
926 		 */
927 		if (handle == 0)
928 			foff = 0;
929 	} else {
930 		vp = (struct vnode *) handle;
931 		if (vp->v_type == VCHR) {
932 			type = OBJT_DEVICE;
933 			handle = (caddr_t) vp->v_rdev;
934 		} else {
935 			struct vattr vat;
936 			int error;
937 
938 			error = VOP_GETATTR(vp, &vat, p->p_ucred, p);
939 			if (error)
940 				return (error);
941 			objsize = round_page(vat.va_size);
942 			type = OBJT_VNODE;
943 		}
944 	}
945 
946 	if (handle == NULL) {
947 		object = NULL;
948 	} else {
949 		object = vm_pager_allocate(type, handle, OFF_TO_IDX(objsize), prot, foff);
950 		if (object == NULL)
951 			return (type == OBJT_DEVICE ? EINVAL : ENOMEM);
952 	}
953 
954 	/*
955 	 * Force device mappings to be shared.
956 	 */
957 	if (type == OBJT_DEVICE) {
958 		flags &= ~(MAP_PRIVATE|MAP_COPY);
959 		flags |= MAP_SHARED;
960 	}
961 
962 	docow = 0;
963 	if ((flags & (MAP_ANON|MAP_SHARED)) == 0) {
964 		docow = MAP_COPY_ON_WRITE | MAP_COPY_NEEDED;
965 	}
966 
967 #if defined(VM_PROT_READ_IS_EXEC)
968 	if (prot & VM_PROT_READ)
969 		prot |= VM_PROT_EXECUTE;
970 
971 	if (maxprot & VM_PROT_READ)
972 		maxprot |= VM_PROT_EXECUTE;
973 #endif
974 
975 	rv = vm_map_find(map, object, foff, addr, size, fitit,
976 			prot, maxprot, docow);
977 
978 
979 	if (rv != KERN_SUCCESS) {
980 		/*
981 		 * Lose the object reference. Will destroy the
982 		 * object if it's an unnamed anonymous mapping
983 		 * or named anonymous without other references.
984 		 */
985 		vm_object_deallocate(object);
986 		goto out;
987 	}
988 
989 	/*
990 	 * "Pre-fault" resident pages.
991 	 */
992 	if ((type == OBJT_VNODE) && (map->pmap != NULL) && (object != NULL)) {
993 		pmap_object_init_pt(map->pmap, *addr,
994 			object, (vm_pindex_t) OFF_TO_IDX(foff), size, 1);
995 	}
996 
997 	/*
998 	 * Shared memory is also shared with children.
999 	 */
1000 	if (flags & (MAP_SHARED|MAP_INHERIT)) {
1001 		rv = vm_map_inherit(map, *addr, *addr + size, VM_INHERIT_SHARE);
1002 		if (rv != KERN_SUCCESS) {
1003 			(void) vm_map_remove(map, *addr, *addr + size);
1004 			goto out;
1005 		}
1006 	}
1007 out:
1008 	switch (rv) {
1009 	case KERN_SUCCESS:
1010 		return (0);
1011 	case KERN_INVALID_ADDRESS:
1012 	case KERN_NO_SPACE:
1013 		return (ENOMEM);
1014 	case KERN_PROTECTION_FAILURE:
1015 		return (EACCES);
1016 	default:
1017 		return (EINVAL);
1018 	}
1019 }
1020