1 /* $OpenBSD: uvm_mmap.c,v 1.69 2007/06/18 21:51:15 pedro Exp $ */
2 /* $NetBSD: uvm_mmap.c,v 1.49 2001/02/18 21:19:08 chs Exp $ */
3
4 /*
5 * Copyright (c) 1997 Charles D. Cranor and Washington University.
6 * Copyright (c) 1991, 1993 The Regents of the University of California.
7 * Copyright (c) 1988 University of Utah.
8 *
9 * All rights reserved.
10 *
11 * This code is derived from software contributed to Berkeley by
12 * the Systems Programming Group of the University of Utah Computer
13 * Science Department.
14 *
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions
17 * are met:
18 * 1. Redistributions of source code must retain the above copyright
19 * notice, this list of conditions and the following disclaimer.
20 * 2. Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in the
22 * documentation and/or other materials provided with the distribution.
23 * 3. All advertising materials mentioning features or use of this software
24 * must display the following acknowledgement:
25 * This product includes software developed by the Charles D. Cranor,
26 * Washington University, University of California, Berkeley and
27 * its contributors.
28 * 4. Neither the name of the University nor the names of its contributors
29 * may be used to endorse or promote products derived from this software
30 * without specific prior written permission.
31 *
32 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
33 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
34 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
35 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
36 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
40 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
41 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
42 * SUCH DAMAGE.
43 *
44 * from: Utah $Hdr: vm_mmap.c 1.6 91/10/21$
45 * @(#)vm_mmap.c 8.5 (Berkeley) 5/19/94
46 * from: Id: uvm_mmap.c,v 1.1.2.14 1998/01/05 21:04:26 chuck Exp
47 */
48
49 /*
50 * uvm_mmap.c: system call interface into VM system, plus kernel vm_mmap
51 * function.
52 */
53 #include <sys/param.h>
54 #include <sys/systm.h>
55 #include <sys/file.h>
56 #include <sys/filedesc.h>
57 #include <sys/resourcevar.h>
58 #include <sys/mman.h>
59 #include <sys/mount.h>
60 #include <sys/proc.h>
61 #include <sys/malloc.h>
62 #include <sys/vnode.h>
63 #include <sys/conf.h>
64 #include <sys/stat.h>
65
66 #include <machine/exec.h> /* for __LDPGSZ */
67
68 #include <miscfs/specfs/specdev.h>
69
70 #include <sys/syscallargs.h>
71
72 #include <uvm/uvm.h>
73 #include <uvm/uvm_device.h>
74 #include <uvm/uvm_vnode.h>
75
76 /*
77 * Page align addr and size, returning EINVAL on wraparound.
78 */
79 #define ALIGN_ADDR(addr, size, pageoff) do { \
80 pageoff = (addr & PAGE_MASK); \
81 if (pageoff != 0) { \
82 if (size > SIZE_MAX - pageoff) \
83 return (EINVAL); /* wraparound */ \
84 addr -= pageoff; \
85 size += pageoff; \
86 } \
87 if (size != 0) { \
88 size = (vsize_t)round_page(size); \
89 if (size == 0) \
90 return (EINVAL); /* wraparound */ \
91 } \
92 } while (0)
93
94 /*
95 * unimplemented VM system calls:
96 */
97
98 /*
99 * sys_sbrk: sbrk system call.
100 */
101
102 /* ARGSUSED */
103 int
104 sys_sbrk(p, v, retval)
105 struct proc *p;
106 void *v;
107 register_t *retval;
108 {
109 #if 0
110 struct sys_sbrk_args /* {
111 syscallarg(int) incr;
112 } */ *uap = v;
113 #endif
114
115 return (ENOSYS);
116 }
117
118 /*
119 * sys_sstk: sstk system call.
120 */
121
122 /* ARGSUSED */
123 int
124 sys_sstk(p, v, retval)
125 struct proc *p;
126 void *v;
127 register_t *retval;
128 {
129 #if 0
130 struct sys_sstk_args /* {
131 syscallarg(int) incr;
132 } */ *uap = v;
133 #endif
134
135 return (ENOSYS);
136 }
137
138 /*
139 * sys_mquery: provide mapping hints to applications that do fixed mappings
140 *
141 * flags: 0 or MAP_FIXED (MAP_FIXED - means that we insist on this addr and
142 * don't care about PMAP_PREFER or such)
143 * addr: hint where we'd like to place the mapping.
144 * size: size of the mapping
145 * fd: fd of the file we want to map
146 * off: offset within the file
147 */
148
149 int
150 sys_mquery(p, v, retval)
151 struct proc *p;
152 void *v;
153 register_t *retval;
154 {
155 struct sys_mquery_args /* {
156 syscallarg(void *) addr;
157 syscallarg(size_t) len;
158 syscallarg(int) prot;
159 syscallarg(int) flags;
160 syscallarg(int) fd;
161 syscallarg(long) pad;
162 syscallarg(off_t) pos;
163 } */ *uap = v;
164 struct file *fp;
165 struct uvm_object *uobj;
166 voff_t uoff;
167 int error;
168 vaddr_t vaddr;
169 int flags = 0;
170 vsize_t size;
171 vm_prot_t prot;
172 int fd;
173
174 vaddr = (vaddr_t) SCARG(uap, addr);
175 prot = SCARG(uap, prot);
176 size = (vsize_t) SCARG(uap, len);
177 fd = SCARG(uap, fd);
178
179 if ((prot & VM_PROT_ALL) != prot)
180 return (EINVAL);
181
182 if (SCARG(uap, flags) & MAP_FIXED)
183 flags |= UVM_FLAG_FIXED;
184
185 if (fd >= 0) {
186 if ((error = getvnode(p->p_fd, fd, &fp)) != 0)
187 return (error);
188 uobj = &((struct vnode *)fp->f_data)->v_uvm.u_obj;
189 uoff = SCARG(uap, pos);
190 } else {
191 fp = NULL;
192 uobj = NULL;
193 uoff = 0;
194 }
195
196 if (vaddr == 0)
197 vaddr = uvm_map_hint(p, prot);
198
199 /* prevent a user requested address from falling in heap space */
200 if ((vaddr + size > (vaddr_t)p->p_vmspace->vm_daddr) &&
201 (vaddr < (vaddr_t)p->p_vmspace->vm_daddr + MAXDSIZ)) {
202 if (flags & UVM_FLAG_FIXED) {
203 error = EINVAL;
204 goto done;
205 }
206 vaddr = round_page((vaddr_t)p->p_vmspace->vm_daddr + MAXDSIZ);
207 }
208 again:
209
210 if (uvm_map_findspace(&p->p_vmspace->vm_map, vaddr, size,
211 &vaddr, uobj, uoff, 0, flags) == NULL) {
212 if (flags & UVM_FLAG_FIXED)
213 error = EINVAL;
214 else
215 error = ENOMEM;
216 } else {
217 /* prevent a returned address from falling in heap space */
218 if ((vaddr + size > (vaddr_t)p->p_vmspace->vm_daddr)
219 && (vaddr < (vaddr_t)p->p_vmspace->vm_daddr + MAXDSIZ)) {
220 vaddr = round_page((vaddr_t)p->p_vmspace->vm_daddr +
221 MAXDSIZ);
222 goto again;
223 }
224 error = 0;
225 *retval = (register_t)(vaddr);
226 }
227 done:
228 if (fp != NULL)
229 FRELE(fp);
230 return (error);
231 }
232
233 /*
234 * sys_mincore: determine if pages are in core or not.
235 */
236
237 /* ARGSUSED */
238 int
239 sys_mincore(p, v, retval)
240 struct proc *p;
241 void *v;
242 register_t *retval;
243 {
244 struct sys_mincore_args /* {
245 syscallarg(void *) addr;
246 syscallarg(size_t) len;
247 syscallarg(char *) vec;
248 } */ *uap = v;
249 vm_page_t m;
250 char *vec, pgi;
251 struct uvm_object *uobj;
252 struct vm_amap *amap;
253 struct vm_anon *anon;
254 vm_map_entry_t entry;
255 vaddr_t start, end, lim;
256 vm_map_t map;
257 vsize_t len, npgs;
258 int error = 0;
259
260 map = &p->p_vmspace->vm_map;
261
262 start = (vaddr_t)SCARG(uap, addr);
263 len = SCARG(uap, len);
264 vec = SCARG(uap, vec);
265
266 if (start & PAGE_MASK)
267 return (EINVAL);
268 len = round_page(len);
269 end = start + len;
270 if (end <= start)
271 return (EINVAL);
272
273 npgs = len >> PAGE_SHIFT;
274
275 /*
276 * Lock down vec, so our returned status isn't outdated by
277 * storing the status byte for a page.
278 */
279 if ((error = uvm_vslock(p, vec, npgs, VM_PROT_WRITE)) != 0)
280 return (error);
281
282 vm_map_lock_read(map);
283
284 if (uvm_map_lookup_entry(map, start, &entry) == FALSE) {
285 error = ENOMEM;
286 goto out;
287 }
288
289 for (/* nothing */;
290 entry != &map->header && entry->start < end;
291 entry = entry->next) {
292 KASSERT(!UVM_ET_ISSUBMAP(entry));
293 KASSERT(start >= entry->start);
294
295 /* Make sure there are no holes. */
296 if (entry->end < end &&
297 (entry->next == &map->header ||
298 entry->next->start > entry->end)) {
299 error = ENOMEM;
300 goto out;
301 }
302
303 lim = end < entry->end ? end : entry->end;
304
305 /*
306 * Special case for objects with no "real" pages. Those
307 * are always considered resident (mapped devices).
308 */
309 if (UVM_ET_ISOBJ(entry)) {
310 KASSERT(!UVM_OBJ_IS_KERN_OBJECT(entry->object.uvm_obj));
311 if (entry->object.uvm_obj->pgops->pgo_releasepg
312 == NULL) {
313 pgi = 1;
314 for (/* nothing */; start < lim;
315 start += PAGE_SIZE, vec++)
316 copyout(&pgi, vec, sizeof(char));
317 continue;
318 }
319 }
320
321 amap = entry->aref.ar_amap; /* top layer */
322 uobj = entry->object.uvm_obj; /* bottom layer */
323
324 if (uobj != NULL)
325 simple_lock(&uobj->vmobjlock);
326
327 for (/* nothing */; start < lim; start += PAGE_SIZE, vec++) {
328 pgi = 0;
329 if (amap != NULL) {
330 /* Check the top layer first. */
331 anon = amap_lookup(&entry->aref,
332 start - entry->start);
333 /* Don't need to lock anon here. */
334 if (anon != NULL && anon->an_page != NULL) {
335 /*
336 * Anon has the page for this entry
337 * offset.
338 */
339 pgi = 1;
340 }
341 }
342
343 if (uobj != NULL && pgi == 0) {
344 /* Check the bottom layer. */
345 m = uvm_pagelookup(uobj,
346 entry->offset + (start - entry->start));
347 if (m != NULL) {
348 /*
349 * Object has the page for this entry
350 * offset.
351 */
352 pgi = 1;
353 }
354 }
355
356 copyout(&pgi, vec, sizeof(char));
357 }
358
359 if (uobj != NULL)
360 simple_unlock(&uobj->vmobjlock);
361 }
362
363 out:
364 vm_map_unlock_read(map);
365 uvm_vsunlock(p, SCARG(uap, vec), npgs);
366 return (error);
367 }
368
369 /*
370 * sys_mmap: mmap system call.
371 *
372 * => file offset and address may not be page aligned
373 * - if MAP_FIXED, offset and address must have remainder mod PAGE_SIZE
374 * - if address isn't page aligned the mapping starts at trunc_page(addr)
375 * and the return value is adjusted up by the page offset.
376 */
377
378 int
379 sys_mmap(p, v, retval)
380 struct proc *p;
381 void *v;
382 register_t *retval;
383 {
384 struct sys_mmap_args /* {
385 syscallarg(void *) addr;
386 syscallarg(size_t) len;
387 syscallarg(int) prot;
388 syscallarg(int) flags;
389 syscallarg(int) fd;
390 syscallarg(long) pad;
391 syscallarg(off_t) pos;
392 } */ *uap = v;
393 vaddr_t addr;
394 struct vattr va;
395 off_t pos;
396 vsize_t size, pageoff;
397 vm_prot_t prot, maxprot;
398 int flags, fd;
399 vaddr_t vm_min_address = VM_MIN_ADDRESS;
400 struct filedesc *fdp = p->p_fd;
401 struct file *fp = NULL;
402 struct vnode *vp;
403 caddr_t handle;
404 int error;
405
406 /*
407 * first, extract syscall args from the uap.
408 */
409
410 addr = (vaddr_t) SCARG(uap, addr);
411 size = (vsize_t) SCARG(uap, len);
412 prot = SCARG(uap, prot);
413 flags = SCARG(uap, flags);
414 fd = SCARG(uap, fd);
415 pos = SCARG(uap, pos);
416
417 /*
418 * Fixup the old deprecated MAP_COPY into MAP_PRIVATE, and
419 * validate the flags.
420 */
421 if ((prot & VM_PROT_ALL) != prot)
422 return (EINVAL);
423 if ((flags & MAP_FLAGMASK) != flags)
424 return (EINVAL);
425 if (flags & MAP_COPY)
426 flags = (flags & ~MAP_COPY) | MAP_PRIVATE;
427 if ((flags & (MAP_SHARED|MAP_PRIVATE)) == (MAP_SHARED|MAP_PRIVATE))
428 return (EINVAL);
429
430 /*
431 * align file position and save offset. adjust size.
432 */
433 ALIGN_ADDR(pos, size, pageoff);
434
435 /*
436 * now check (MAP_FIXED) or get (!MAP_FIXED) the "addr"
437 */
438
439 if (flags & MAP_FIXED) {
440
441 /* adjust address by the same amount as we did the offset */
442 addr -= pageoff;
443 if (addr & PAGE_MASK)
444 return (EINVAL); /* not page aligned */
445
446 if (addr > SIZE_MAX - size)
447 return (EINVAL); /* no wrapping! */
448 if (VM_MAXUSER_ADDRESS > 0 &&
449 (addr + size) > VM_MAXUSER_ADDRESS)
450 return (EINVAL);
451 if (vm_min_address > 0 && addr < vm_min_address)
452 return (EINVAL);
453
454 } else {
455
456 /*
457 * not fixed: make sure we skip over the largest possible heap.
458 * we will refine our guess later (e.g. to account for VAC, etc)
459 */
460 if (addr == 0)
461 addr = uvm_map_hint(p, prot);
462 else if (!(flags & MAP_TRYFIXED) &&
463 addr < (vaddr_t)p->p_vmspace->vm_daddr)
464 addr = uvm_map_hint(p, prot);
465 }
466
467 /*
468 * check for file mappings (i.e. not anonymous) and verify file.
469 */
470 if ((flags & MAP_ANON) == 0) {
471
472 if ((fp = fd_getfile(fdp, fd)) == NULL)
473 return (EBADF);
474
475 FREF(fp);
476
477 if (fp->f_type != DTYPE_VNODE) {
478 error = ENODEV; /* only mmap vnodes! */
479 goto out;
480 }
481 vp = (struct vnode *)fp->f_data; /* convert to vnode */
482
483 if (vp->v_type != VREG && vp->v_type != VCHR &&
484 vp->v_type != VBLK) {
485 error = ENODEV; /* only REG/CHR/BLK support mmap */
486 goto out;
487 }
488
489 if (vp->v_type == VREG && (pos + size) < pos) {
490 error = EINVAL; /* no offset wrapping */
491 goto out;
492 }
493
494 /* special case: catch SunOS style /dev/zero */
495 if (vp->v_type == VCHR && iszerodev(vp->v_rdev)) {
496 flags |= MAP_ANON;
497 FRELE(fp);
498 fp = NULL;
499 goto is_anon;
500 }
501
502 /*
503 * Old programs may not select a specific sharing type, so
504 * default to an appropriate one.
505 *
506 * XXX: how does MAP_ANON fit in the picture?
507 */
508 if ((flags & (MAP_SHARED|MAP_PRIVATE)) == 0) {
509 #if defined(DEBUG)
510 printf("WARNING: defaulted mmap() share type to "
511 "%s (pid %d comm %s)\n", vp->v_type == VCHR ?
512 "MAP_SHARED" : "MAP_PRIVATE", p->p_pid,
513 p->p_comm);
514 #endif
515 if (vp->v_type == VCHR)
516 flags |= MAP_SHARED; /* for a device */
517 else
518 flags |= MAP_PRIVATE; /* for a file */
519 }
520
521 /*
522 * MAP_PRIVATE device mappings don't make sense (and aren't
523 * supported anyway). However, some programs rely on this,
524 * so just change it to MAP_SHARED.
525 */
526 if (vp->v_type == VCHR && (flags & MAP_PRIVATE) != 0) {
527 flags = (flags & ~MAP_PRIVATE) | MAP_SHARED;
528 }
529
530 /*
531 * now check protection
532 */
533
534 maxprot = VM_PROT_EXECUTE;
535
536 /* check read access */
537 if (fp->f_flag & FREAD)
538 maxprot |= VM_PROT_READ;
539 else if (prot & PROT_READ) {
540 error = EACCES;
541 goto out;
542 }
543
544 /* check write access, shared case first */
545 if (flags & MAP_SHARED) {
546 /*
547 * if the file is writable, only add PROT_WRITE to
548 * maxprot if the file is not immutable, append-only.
549 * otherwise, if we have asked for PROT_WRITE, return
550 * EPERM.
551 */
552 if (fp->f_flag & FWRITE) {
553 if ((error =
554 VOP_GETATTR(vp, &va, p->p_ucred, p)))
555 goto out;
556 if ((va.va_flags & (IMMUTABLE|APPEND)) == 0)
557 maxprot |= VM_PROT_WRITE;
558 else if (prot & PROT_WRITE) {
559 error = EPERM;
560 goto out;
561 }
562 } else if (prot & PROT_WRITE) {
563 error = EACCES;
564 goto out;
565 }
566 } else {
567 /* MAP_PRIVATE mappings can always write to */
568 maxprot |= VM_PROT_WRITE;
569 }
570
571 /*
572 * set handle to vnode
573 */
574
575 handle = (caddr_t)vp;
576
577 } else { /* MAP_ANON case */
578 /*
579 * XXX What do we do about (MAP_SHARED|MAP_PRIVATE) == 0?
580 */
581 if (fd != -1) {
582 error = EINVAL;
583 goto out;
584 }
585
586 is_anon: /* label for SunOS style /dev/zero */
587 handle = NULL;
588 maxprot = VM_PROT_ALL;
589 pos = 0;
590 }
591
592 if ((flags & MAP_ANON) != 0 ||
593 ((flags & MAP_PRIVATE) != 0 && (prot & PROT_WRITE) != 0)) {
594 if (size >
595 (p->p_rlimit[RLIMIT_DATA].rlim_cur - ctob(p->p_vmspace->vm_dused))) {
596 error = ENOMEM;
597 goto out;
598 }
599 }
600
601 /*
602 * now let kernel internal function uvm_mmap do the work.
603 */
604
605 error = uvm_mmap(&p->p_vmspace->vm_map, &addr, size, prot, maxprot,
606 flags, handle, pos, p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur, p);
607
608 if (error == 0)
609 /* remember to add offset */
610 *retval = (register_t)(addr + pageoff);
611
612 out:
613 if (fp)
614 FRELE(fp);
615 return (error);
616 }
617
618 /*
619 * sys_msync: the msync system call (a front-end for flush)
620 */
621
622 int
623 sys_msync(p, v, retval)
624 struct proc *p;
625 void *v;
626 register_t *retval;
627 {
628 struct sys_msync_args /* {
629 syscallarg(void *) addr;
630 syscallarg(size_t) len;
631 syscallarg(int) flags;
632 } */ *uap = v;
633 vaddr_t addr;
634 vsize_t size, pageoff;
635 vm_map_t map;
636 int rv, flags, uvmflags;
637
638 /*
639 * extract syscall args from the uap
640 */
641
642 addr = (vaddr_t)SCARG(uap, addr);
643 size = (vsize_t)SCARG(uap, len);
644 flags = SCARG(uap, flags);
645
646 /* sanity check flags */
647 if ((flags & ~(MS_ASYNC | MS_SYNC | MS_INVALIDATE)) != 0 ||
648 (flags & (MS_ASYNC | MS_SYNC | MS_INVALIDATE)) == 0 ||
649 (flags & (MS_ASYNC | MS_SYNC)) == (MS_ASYNC | MS_SYNC))
650 return (EINVAL);
651 if ((flags & (MS_ASYNC | MS_SYNC)) == 0)
652 flags |= MS_SYNC;
653
654 /*
655 * align the address to a page boundary, and adjust the size accordingly
656 */
657 ALIGN_ADDR(addr, size, pageoff);
658 if (addr > SIZE_MAX - size)
659 return (EINVAL); /* disallow wrap-around. */
660
661 /*
662 * get map
663 */
664
665 map = &p->p_vmspace->vm_map;
666
667 /*
668 * XXXCDC: do we really need this semantic?
669 *
670 * XXX Gak! If size is zero we are supposed to sync "all modified
671 * pages with the region containing addr". Unfortunately, we
672 * don't really keep track of individual mmaps so we approximate
673 * by flushing the range of the map entry containing addr.
674 * This can be incorrect if the region splits or is coalesced
675 * with a neighbor.
676 */
677 if (size == 0) {
678 vm_map_entry_t entry;
679
680 vm_map_lock_read(map);
681 rv = uvm_map_lookup_entry(map, addr, &entry);
682 if (rv == TRUE) {
683 addr = entry->start;
684 size = entry->end - entry->start;
685 }
686 vm_map_unlock_read(map);
687 if (rv == FALSE)
688 return (EINVAL);
689 }
690
691 /*
692 * translate MS_ flags into PGO_ flags
693 */
694 uvmflags = PGO_CLEANIT;
695 if (flags & MS_INVALIDATE)
696 uvmflags |= PGO_FREE;
697 if (flags & MS_SYNC)
698 uvmflags |= PGO_SYNCIO;
699 else
700 uvmflags |= PGO_SYNCIO; /* XXXCDC: force sync for now! */
701
702 return (uvm_map_clean(map, addr, addr+size, uvmflags));
703 }
704
705 /*
706 * sys_munmap: unmap a users memory
707 */
708
709 int
710 sys_munmap(p, v, retval)
711 struct proc *p;
712 void *v;
713 register_t *retval;
714 {
715 struct sys_munmap_args /* {
716 syscallarg(void *) addr;
717 syscallarg(size_t) len;
718 } */ *uap = v;
719 vaddr_t addr;
720 vsize_t size, pageoff;
721 vm_map_t map;
722 vaddr_t vm_min_address = VM_MIN_ADDRESS;
723 struct vm_map_entry *dead_entries;
724
725 /*
726 * get syscall args...
727 */
728
729 addr = (vaddr_t) SCARG(uap, addr);
730 size = (vsize_t) SCARG(uap, len);
731
732 /*
733 * align the address to a page boundary, and adjust the size accordingly
734 */
735 ALIGN_ADDR(addr, size, pageoff);
736
737 /*
738 * Check for illegal addresses. Watch out for address wrap...
739 * Note that VM_*_ADDRESS are not constants due to casts (argh).
740 */
741 if (addr > SIZE_MAX - size)
742 return (EINVAL);
743 if (VM_MAXUSER_ADDRESS > 0 && addr + size > VM_MAXUSER_ADDRESS)
744 return (EINVAL);
745 if (vm_min_address > 0 && addr < vm_min_address)
746 return (EINVAL);
747 map = &p->p_vmspace->vm_map;
748
749
750 vm_map_lock(map); /* lock map so we can checkprot */
751
752 /*
753 * interesting system call semantic: make sure entire range is
754 * allocated before allowing an unmap.
755 */
756
757 if (!uvm_map_checkprot(map, addr, addr + size, VM_PROT_NONE)) {
758 vm_map_unlock(map);
759 return (EINVAL);
760 }
761
762 /*
763 * doit!
764 */
765 uvm_unmap_remove(map, addr, addr + size, &dead_entries, p);
766
767 vm_map_unlock(map); /* and unlock */
768
769 if (dead_entries != NULL)
770 uvm_unmap_detach(dead_entries, 0);
771
772 return (0);
773 }
774
775 /*
776 * sys_mprotect: the mprotect system call
777 */
778
779 int
780 sys_mprotect(p, v, retval)
781 struct proc *p;
782 void *v;
783 register_t *retval;
784 {
785 struct sys_mprotect_args /* {
786 syscallarg(void *) addr;
787 syscallarg(size_t) len;
788 syscallarg(int) prot;
789 } */ *uap = v;
790 vaddr_t addr;
791 vsize_t size, pageoff;
792 vm_prot_t prot;
793
794 /*
795 * extract syscall args from uap
796 */
797
798 addr = (vaddr_t)SCARG(uap, addr);
799 size = (vsize_t)SCARG(uap, len);
800 prot = SCARG(uap, prot);
801
802 if ((prot & VM_PROT_ALL) != prot)
803 return (EINVAL);
804
805 /*
806 * align the address to a page boundary, and adjust the size accordingly
807 */
808 ALIGN_ADDR(addr, size, pageoff);
809 if (addr > SIZE_MAX - size)
810 return (EINVAL); /* disallow wrap-around. */
811
812 return (uvm_map_protect(&p->p_vmspace->vm_map, addr, addr+size,
813 prot, FALSE));
814 }
815
816 /*
817 * sys_minherit: the minherit system call
818 */
819
820 int
821 sys_minherit(p, v, retval)
822 struct proc *p;
823 void *v;
824 register_t *retval;
825 {
826 struct sys_minherit_args /* {
827 syscallarg(void *) addr;
828 syscallarg(size_t) len;
829 syscallarg(int) inherit;
830 } */ *uap = v;
831 vaddr_t addr;
832 vsize_t size, pageoff;
833 vm_inherit_t inherit;
834
835 addr = (vaddr_t)SCARG(uap, addr);
836 size = (vsize_t)SCARG(uap, len);
837 inherit = SCARG(uap, inherit);
838
839 /*
840 * align the address to a page boundary, and adjust the size accordingly
841 */
842 ALIGN_ADDR(addr, size, pageoff);
843 if (addr > SIZE_MAX - size)
844 return (EINVAL); /* disallow wrap-around. */
845
846 return (uvm_map_inherit(&p->p_vmspace->vm_map, addr, addr+size,
847 inherit));
848 }
849
850 /*
851 * sys_madvise: give advice about memory usage.
852 */
853
854 /* ARGSUSED */
855 int
856 sys_madvise(p, v, retval)
857 struct proc *p;
858 void *v;
859 register_t *retval;
860 {
861 struct sys_madvise_args /* {
862 syscallarg(void *) addr;
863 syscallarg(size_t) len;
864 syscallarg(int) behav;
865 } */ *uap = v;
866 vaddr_t addr;
867 vsize_t size, pageoff;
868 int advice, error;
869
870 addr = (vaddr_t)SCARG(uap, addr);
871 size = (vsize_t)SCARG(uap, len);
872 advice = SCARG(uap, behav);
873
874 /*
875 * align the address to a page boundary, and adjust the size accordingly
876 */
877 ALIGN_ADDR(addr, size, pageoff);
878 if (addr > SIZE_MAX - size)
879 return (EINVAL); /* disallow wrap-around. */
880
881 switch (advice) {
882 case MADV_NORMAL:
883 case MADV_RANDOM:
884 case MADV_SEQUENTIAL:
885 error = uvm_map_advice(&p->p_vmspace->vm_map, addr,
886 addr + size, advice);
887 break;
888
889 case MADV_WILLNEED:
890 /*
891 * Activate all these pages, pre-faulting them in if
892 * necessary.
893 */
894 /*
895 * XXX IMPLEMENT ME.
896 * Should invent a "weak" mode for uvm_fault()
897 * which would only do the PGO_LOCKED pgo_get().
898 */
899 return (0);
900
901 case MADV_DONTNEED:
902 /*
903 * Deactivate all these pages. We don't need them
904 * any more. We don't, however, toss the data in
905 * the pages.
906 */
907 error = uvm_map_clean(&p->p_vmspace->vm_map, addr, addr + size,
908 PGO_DEACTIVATE);
909 break;
910
911 case MADV_FREE:
912 /*
913 * These pages contain no valid data, and may be
914 * garbage-collected. Toss all resources, including
915 * any swap space in use.
916 */
917 error = uvm_map_clean(&p->p_vmspace->vm_map, addr, addr + size,
918 PGO_FREE);
919 break;
920
921 case MADV_SPACEAVAIL:
922 /*
923 * XXXMRG What is this? I think it's:
924 *
925 * Ensure that we have allocated backing-store
926 * for these pages.
927 *
928 * This is going to require changes to the page daemon,
929 * as it will free swap space allocated to pages in core.
930 * There's also what to do for device/file/anonymous memory.
931 */
932 return (EINVAL);
933
934 default:
935 return (EINVAL);
936 }
937
938 return (error);
939 }
940
941 /*
942 * sys_mlock: memory lock
943 */
944
945 int
946 sys_mlock(p, v, retval)
947 struct proc *p;
948 void *v;
949 register_t *retval;
950 {
951 struct sys_mlock_args /* {
952 syscallarg(const void *) addr;
953 syscallarg(size_t) len;
954 } */ *uap = v;
955 vaddr_t addr;
956 vsize_t size, pageoff;
957 int error;
958
959 /*
960 * extract syscall args from uap
961 */
962 addr = (vaddr_t)SCARG(uap, addr);
963 size = (vsize_t)SCARG(uap, len);
964
965 /*
966 * align the address to a page boundary and adjust the size accordingly
967 */
968 ALIGN_ADDR(addr, size, pageoff);
969 if (addr > SIZE_MAX - size)
970 return (EINVAL); /* disallow wrap-around. */
971
972 if (atop(size) + uvmexp.wired > uvmexp.wiredmax)
973 return (EAGAIN);
974
975 #ifdef pmap_wired_count
976 if (size + ptoa(pmap_wired_count(vm_map_pmap(&p->p_vmspace->vm_map))) >
977 p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur)
978 return (EAGAIN);
979 #else
980 if ((error = suser(p, 0)) != 0)
981 return (error);
982 #endif
983
984 error = uvm_map_pageable(&p->p_vmspace->vm_map, addr, addr+size, FALSE,
985 0);
986 return (error == 0 ? 0 : ENOMEM);
987 }
988
989 /*
990 * sys_munlock: unlock wired pages
991 */
992
993 int
994 sys_munlock(p, v, retval)
995 struct proc *p;
996 void *v;
997 register_t *retval;
998 {
999 struct sys_munlock_args /* {
1000 syscallarg(const void *) addr;
1001 syscallarg(size_t) len;
1002 } */ *uap = v;
1003 vaddr_t addr;
1004 vsize_t size, pageoff;
1005 int error;
1006
1007 /*
1008 * extract syscall args from uap
1009 */
1010
1011 addr = (vaddr_t)SCARG(uap, addr);
1012 size = (vsize_t)SCARG(uap, len);
1013
1014 /*
1015 * align the address to a page boundary, and adjust the size accordingly
1016 */
1017 ALIGN_ADDR(addr, size, pageoff);
1018 if (addr > SIZE_MAX - size)
1019 return (EINVAL); /* disallow wrap-around. */
1020
1021 #ifndef pmap_wired_count
1022 if ((error = suser(p, 0)) != 0)
1023 return (error);
1024 #endif
1025
1026 error = uvm_map_pageable(&p->p_vmspace->vm_map, addr, addr+size, TRUE,
1027 0);
1028 return (error == 0 ? 0 : ENOMEM);
1029 }
1030
1031 /*
1032 * sys_mlockall: lock all pages mapped into an address space.
1033 */
1034
1035 int
1036 sys_mlockall(p, v, retval)
1037 struct proc *p;
1038 void *v;
1039 register_t *retval;
1040 {
1041 struct sys_mlockall_args /* {
1042 syscallarg(int) flags;
1043 } */ *uap = v;
1044 int error, flags;
1045
1046 flags = SCARG(uap, flags);
1047
1048 if (flags == 0 ||
1049 (flags & ~(MCL_CURRENT|MCL_FUTURE)) != 0)
1050 return (EINVAL);
1051
1052 #ifndef pmap_wired_count
1053 if ((error = suser(p, 0)) != 0)
1054 return (error);
1055 #endif
1056
1057 error = uvm_map_pageable_all(&p->p_vmspace->vm_map, flags,
1058 p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur);
1059 if (error != 0 && error != ENOMEM)
1060 return (EAGAIN);
1061 return (error);
1062 }
1063
1064 /*
1065 * sys_munlockall: unlock all pages mapped into an address space.
1066 */
1067
1068 int
1069 sys_munlockall(p, v, retval)
1070 struct proc *p;
1071 void *v;
1072 register_t *retval;
1073 {
1074
1075 (void) uvm_map_pageable_all(&p->p_vmspace->vm_map, 0, 0);
1076 return (0);
1077 }
1078
1079 /*
1080 * uvm_mmap: internal version of mmap
1081 *
1082 * - used by sys_mmap, exec, and sysv shm
1083 * - handle is a vnode pointer or NULL for MAP_ANON (XXX: not true,
1084 * sysv shm uses "named anonymous memory")
1085 * - caller must page-align the file offset
1086 */
1087
1088 int
1089 uvm_mmap(map, addr, size, prot, maxprot, flags, handle, foff, locklimit, p)
1090 vm_map_t map;
1091 vaddr_t *addr;
1092 vsize_t size;
1093 vm_prot_t prot, maxprot;
1094 int flags;
1095 caddr_t handle; /* XXX: VNODE? */
1096 voff_t foff;
1097 vsize_t locklimit;
1098 struct proc *p;
1099 {
1100 struct uvm_object *uobj;
1101 struct vnode *vp;
1102 int error;
1103 int advice = UVM_ADV_NORMAL;
1104 uvm_flag_t uvmflag = 0;
1105 vsize_t align = 0; /* userland page size */
1106
1107 /*
1108 * check params
1109 */
1110
1111 if (size == 0)
1112 return(0);
1113 if (foff & PAGE_MASK)
1114 return(EINVAL);
1115 if ((prot & maxprot) != prot)
1116 return(EINVAL);
1117
1118 /*
1119 * for non-fixed mappings, round off the suggested address.
1120 * for fixed mappings, check alignment and zap old mappings.
1121 */
1122
1123 if ((flags & MAP_FIXED) == 0) {
1124 *addr = round_page(*addr); /* round */
1125 } else {
1126 if (*addr & PAGE_MASK)
1127 return(EINVAL);
1128 uvmflag |= UVM_FLAG_FIXED;
1129 uvm_unmap_p(map, *addr, *addr + size, p); /* zap! */
1130 }
1131
1132 /*
1133 * handle anon vs. non-anon mappings. for non-anon mappings attach
1134 * to underlying vm object.
1135 */
1136
1137 if (flags & MAP_ANON) {
1138 if ((flags & MAP_FIXED) == 0 && size >= __LDPGSZ)
1139 align = __LDPGSZ;
1140 foff = UVM_UNKNOWN_OFFSET;
1141 uobj = NULL;
1142 if ((flags & MAP_SHARED) == 0)
1143 /* XXX: defer amap create */
1144 uvmflag |= UVM_FLAG_COPYONW;
1145 else
1146 /* shared: create amap now */
1147 uvmflag |= UVM_FLAG_OVERLAY;
1148
1149 } else {
1150
1151 vp = (struct vnode *) handle; /* get vnode */
1152 if (vp->v_type != VCHR) {
1153 uobj = uvn_attach((void *) vp, (flags & MAP_SHARED) ?
1154 maxprot : (maxprot & ~VM_PROT_WRITE));
1155
1156 #ifndef UBC
1157 /*
1158 * XXXCDC: hack from old code
1159 * don't allow vnodes which have been mapped
1160 * shared-writeable to persist [forces them to be
1161 * flushed out when last reference goes].
1162 * XXXCDC: interesting side effect: avoids a bug.
1163 * note that in WRITE [ufs_readwrite.c] that we
1164 * allocate buffer, uncache, and then do the write.
1165 * the problem with this is that if the uncache causes
1166 * VM data to be flushed to the same area of the file
1167 * we are writing to... in that case we've got the
1168 * buffer locked and our process goes to sleep forever.
1169 *
1170 * XXXCDC: checking maxprot protects us from the
1171 * "persistbug" program but this is not a long term
1172 * solution.
1173 *
1174 * XXXCDC: we don't bother calling uncache with the vp
1175 * VOP_LOCKed since we know that we are already
1176 * holding a valid reference to the uvn (from the
1177 * uvn_attach above), and thus it is impossible for
1178 * the uncache to kill the uvn and trigger I/O.
1179 */
1180 if (flags & MAP_SHARED) {
1181 if ((prot & VM_PROT_WRITE) ||
1182 (maxprot & VM_PROT_WRITE)) {
1183 uvm_vnp_uncache(vp);
1184 }
1185 }
1186 #else
1187 /* XXX for now, attach doesn't gain a ref */
1188 VREF(vp);
1189 #endif
1190 } else {
1191 uobj = udv_attach((void *) &vp->v_rdev,
1192 (flags & MAP_SHARED) ? maxprot :
1193 (maxprot & ~VM_PROT_WRITE), foff, size);
1194 /*
1195 * XXX Some devices don't like to be mapped with
1196 * XXX PROT_EXEC, but we don't really have a
1197 * XXX better way of handling this, right now
1198 */
1199 if (uobj == NULL && (prot & PROT_EXEC) == 0) {
1200 maxprot &= ~VM_PROT_EXECUTE;
1201 uobj = udv_attach((void *) &vp->v_rdev,
1202 (flags & MAP_SHARED) ? maxprot :
1203 (maxprot & ~VM_PROT_WRITE), foff, size);
1204 }
1205 advice = UVM_ADV_RANDOM;
1206 }
1207
1208 if (uobj == NULL)
1209 return((vp->v_type == VREG) ? ENOMEM : EINVAL);
1210
1211 if ((flags & MAP_SHARED) == 0)
1212 uvmflag |= UVM_FLAG_COPYONW;
1213 }
1214
1215 /*
1216 * set up mapping flags
1217 */
1218
1219 uvmflag = UVM_MAPFLAG(prot, maxprot,
1220 (flags & MAP_SHARED) ? UVM_INH_SHARE : UVM_INH_COPY,
1221 advice, uvmflag);
1222
1223 error = uvm_map_p(map, addr, size, uobj, foff, align, uvmflag, p);
1224
1225 if (error == 0) {
1226 /*
1227 * POSIX 1003.1b -- if our address space was configured
1228 * to lock all future mappings, wire the one we just made.
1229 */
1230 if (prot == VM_PROT_NONE) {
1231 /*
1232 * No more work to do in this case.
1233 */
1234 return (0);
1235 }
1236
1237 vm_map_lock(map);
1238
1239 if (map->flags & VM_MAP_WIREFUTURE) {
1240 if ((atop(size) + uvmexp.wired) > uvmexp.wiredmax
1241 #ifdef pmap_wired_count
1242 || (locklimit != 0 && (size +
1243 ptoa(pmap_wired_count(vm_map_pmap(map)))) >
1244 locklimit)
1245 #endif
1246 ) {
1247 error = ENOMEM;
1248 vm_map_unlock(map);
1249 /* unmap the region! */
1250 uvm_unmap(map, *addr, *addr + size);
1251 goto bad;
1252 }
1253 /*
1254 * uvm_map_pageable() always returns the map
1255 * unlocked.
1256 */
1257 error = uvm_map_pageable(map, *addr, *addr + size,
1258 FALSE, UVM_LK_ENTER);
1259 if (error != 0) {
1260 /* unmap the region! */
1261 uvm_unmap(map, *addr, *addr + size);
1262 goto bad;
1263 }
1264 return (0);
1265 }
1266
1267 vm_map_unlock(map);
1268
1269 return (0);
1270 }
1271
1272 /*
1273 * errors: first detach from the uobj, if any.
1274 */
1275
1276 if (uobj)
1277 uobj->pgops->pgo_detach(uobj);
1278
1279 bad:
1280 return (error);
1281 }