1 /* $NetBSD: uvm_mmap.c,v 1.186 2025/02/24 21:32:26 andvar Exp $ */ 2 3 /* 4 * Copyright (c) 1997 Charles D. Cranor and Washington University. 5 * Copyright (c) 1991, 1993 The Regents of the University of California. 6 * Copyright (c) 1988 University of Utah. 7 * 8 * All rights reserved. 9 * 10 * This code is derived from software contributed to Berkeley by 11 * the Systems Programming Group of the University of Utah Computer 12 * Science Department. 13 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions 16 * are met: 17 * 1. Redistributions of source code must retain the above copyright 18 * notice, this list of conditions and the following disclaimer. 19 * 2. Redistributions in binary form must reproduce the above copyright 20 * notice, this list of conditions and the following disclaimer in the 21 * documentation and/or other materials provided with the distribution. 22 * 3. 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 * @(#)vm_mmap.c 8.5 (Berkeley) 5/19/94 40 * from: Id: uvm_mmap.c,v 1.1.2.14 1998/01/05 21:04:26 chuck Exp 41 */ 42 43 /* 44 * uvm_mmap.c: system call interface into VM system, plus kernel vm_mmap 45 * function. 46 */ 47 48 #include <sys/cdefs.h> 49 __KERNEL_RCSID(0, "$NetBSD: uvm_mmap.c,v 1.186 2025/02/24 21:32:26 andvar Exp $"); 50 51 #include "opt_compat_netbsd.h" 52 #include "opt_pax.h" 53 54 #include <sys/param.h> 55 #include <sys/types.h> 56 #include <sys/file.h> 57 #include <sys/filedesc.h> 58 #include <sys/resourcevar.h> 59 #include <sys/mman.h> 60 #include <sys/pax.h> 61 62 #include <sys/syscallargs.h> 63 64 #include <uvm/uvm.h> 65 #include <uvm/uvm_device.h> 66 67 static int uvm_mmap(struct vm_map *, vaddr_t *, vsize_t, vm_prot_t, vm_prot_t, 68 int, int, struct uvm_object *, voff_t, vsize_t); 69 70 static int 71 range_test(const struct vm_map *map, vaddr_t addr, vsize_t size, bool ismmap) 72 { 73 vaddr_t vm_min_address = vm_map_min(map); 74 vaddr_t vm_max_address = vm_map_max(map); 75 vaddr_t eaddr = addr + size; 76 int res = 0; 77 78 if (addr < vm_min_address) 79 return EINVAL; 80 if (eaddr > vm_max_address) 81 return ismmap ? EFBIG : EINVAL; 82 if (addr > eaddr) /* no wrapping! */ 83 return ismmap ? EOVERFLOW : EINVAL; 84 85 #ifdef MD_MMAP_RANGE_TEST 86 res = MD_MMAP_RANGE_TEST(addr, eaddr); 87 #endif 88 89 return res; 90 } 91 92 /* 93 * align the address to a page boundary, and adjust the size accordingly 94 */ 95 static int 96 round_and_check(const struct vm_map *map, vaddr_t *addr, vsize_t *size) 97 { 98 const vsize_t pageoff = (vsize_t)(*addr & PAGE_MASK); 99 100 *addr -= pageoff; 101 102 if (*size != 0) { 103 *size += pageoff; 104 *size = (vsize_t)round_page(*size); 105 } else if (*addr + *size < *addr) { 106 return ENOMEM; 107 } 108 109 return range_test(map, *addr, *size, false); 110 } 111 112 /* 113 * sys_mincore: determine if pages are in core or not. 114 */ 115 116 /* ARGSUSED */ 117 int 118 sys_mincore(struct lwp *l, const struct sys_mincore_args *uap, 119 register_t *retval) 120 { 121 /* { 122 syscallarg(void *) addr; 123 syscallarg(size_t) len; 124 syscallarg(char *) vec; 125 } */ 126 struct proc *p = l->l_proc; 127 struct vm_page *pg; 128 char *vec, pgi; 129 struct uvm_object *uobj; 130 struct vm_amap *amap; 131 struct vm_anon *anon; 132 struct vm_map_entry *entry; 133 vaddr_t start, end, lim; 134 struct vm_map *map; 135 vsize_t len; 136 int error = 0; 137 size_t npgs; 138 139 map = &p->p_vmspace->vm_map; 140 141 start = (vaddr_t)SCARG(uap, addr); 142 len = SCARG(uap, len); 143 vec = SCARG(uap, vec); 144 145 if (start & PAGE_MASK) 146 return EINVAL; 147 len = round_page(len); 148 end = start + len; 149 if (end <= start) 150 return EINVAL; 151 152 /* 153 * Lock down vec, so our returned status isn't outdated by 154 * storing the status byte for a page. 155 */ 156 157 npgs = len >> PAGE_SHIFT; 158 error = uvm_vslock(p->p_vmspace, vec, npgs, VM_PROT_WRITE); 159 if (error) { 160 return error; 161 } 162 vm_map_lock_read(map); 163 164 if (uvm_map_lookup_entry(map, start, &entry) == false) { 165 error = ENOMEM; 166 goto out; 167 } 168 169 for (/* nothing */; 170 entry != &map->header && entry->start < end; 171 entry = entry->next) { 172 KASSERT(!UVM_ET_ISSUBMAP(entry)); 173 KASSERT(start >= entry->start); 174 175 /* Make sure there are no holes. */ 176 if (entry->end < end && 177 (entry->next == &map->header || 178 entry->next->start > entry->end)) { 179 error = ENOMEM; 180 goto out; 181 } 182 183 lim = end < entry->end ? end : entry->end; 184 185 /* 186 * Special case for objects with no "real" pages. Those 187 * are always considered resident (mapped devices). 188 */ 189 190 if (UVM_ET_ISOBJ(entry)) { 191 KASSERT(!UVM_OBJ_IS_KERN_OBJECT(entry->object.uvm_obj)); 192 if (UVM_OBJ_IS_DEVICE(entry->object.uvm_obj)) { 193 for (/* nothing */; start < lim; 194 start += PAGE_SIZE, vec++) 195 ustore_char(vec, 1); 196 continue; 197 } 198 } 199 200 amap = entry->aref.ar_amap; /* upper layer */ 201 uobj = entry->object.uvm_obj; /* lower layer */ 202 203 if (amap != NULL) 204 amap_lock(amap, RW_READER); 205 if (uobj != NULL) 206 rw_enter(uobj->vmobjlock, RW_READER); 207 208 for (/* nothing */; start < lim; start += PAGE_SIZE, vec++) { 209 pgi = 0; 210 if (amap != NULL) { 211 /* Check the upper layer first. */ 212 anon = amap_lookup(&entry->aref, 213 start - entry->start); 214 /* Don't need to lock anon here. */ 215 if (anon != NULL && anon->an_page != NULL) { 216 217 /* 218 * Anon has the page for this entry 219 * offset. 220 */ 221 222 pgi = 1; 223 } 224 } 225 if (uobj != NULL && pgi == 0) { 226 /* Check the lower layer. */ 227 pg = uvm_pagelookup(uobj, 228 entry->offset + (start - entry->start)); 229 if (pg != NULL) { 230 231 /* 232 * Object has the page for this entry 233 * offset. 234 */ 235 236 pgi = 1; 237 } 238 } 239 (void) ustore_char(vec, pgi); 240 } 241 if (uobj != NULL) 242 rw_exit(uobj->vmobjlock); 243 if (amap != NULL) 244 amap_unlock(amap); 245 } 246 247 out: 248 vm_map_unlock_read(map); 249 uvm_vsunlock(p->p_vmspace, SCARG(uap, vec), npgs); 250 return error; 251 } 252 253 /* 254 * sys_mmap: mmap system call. 255 * 256 * => file offset and address may not be page aligned 257 * - if MAP_FIXED, offset and address must have remainder mod PAGE_SIZE 258 * - if address isn't page aligned the mapping starts at trunc_page(addr) 259 * and the return value is adjusted up by the page offset. 260 */ 261 262 int 263 sys_mmap(struct lwp *l, const struct sys_mmap_args *uap, register_t *retval) 264 { 265 /* { 266 syscallarg(void *) addr; 267 syscallarg(size_t) len; 268 syscallarg(int) prot; 269 syscallarg(int) flags; 270 syscallarg(int) fd; 271 syscallarg(long) pad; 272 syscallarg(off_t) pos; 273 } */ 274 struct proc *p = l->l_proc; 275 vaddr_t addr; 276 off_t pos; 277 vsize_t size, pageoff; 278 vm_prot_t prot, maxprot, extraprot; 279 int flags, fd, advice; 280 vaddr_t defaddr = 0; /* XXXGCC */ 281 bool addrhint = false; 282 struct file *fp = NULL; 283 struct uvm_object *uobj; 284 int error; 285 vaddr_t orig_addr; 286 287 /* 288 * first, extract syscall args from the uap. 289 */ 290 291 addr = (vaddr_t)SCARG(uap, addr); 292 size = (vsize_t)SCARG(uap, len); 293 prot = SCARG(uap, prot) & VM_PROT_ALL; 294 extraprot = PROT_MPROTECT_EXTRACT(SCARG(uap, prot)); 295 flags = SCARG(uap, flags); 296 fd = SCARG(uap, fd); 297 pos = SCARG(uap, pos); 298 299 orig_addr = addr; 300 301 if ((flags & (MAP_SHARED|MAP_PRIVATE)) == (MAP_SHARED|MAP_PRIVATE)) 302 return EINVAL; 303 304 if (size == 0 && (flags & MAP_ANON) == 0) 305 return EINVAL; 306 307 /* 308 * Align file position and save offset into page. Adjust size 309 * so that it is an integral multiple of the page size. 310 */ 311 pageoff = pos & PAGE_MASK; 312 pos -= pageoff; 313 KASSERT(PAGE_MASK <= __type_max(vsize_t)); 314 KASSERT((__type_max(vsize_t) - PAGE_SIZE + 1) % PAGE_SIZE == 0); 315 if (size > __type_max(vsize_t) - PAGE_SIZE + 1 - pageoff) 316 return ENOMEM; 317 /* 318 * size + pageoff <= VSIZE_MAX + 1 - PAGE_SIZE, and the 319 * right-hand side is an integral multiple of the page size, so 320 * round_page(size + pageoff) <= VSIZE_MAX + 1 - PAGE_SIZE. 321 */ 322 size = round_page(size + pageoff); 323 324 /* 325 * now check (MAP_FIXED) or get (!MAP_FIXED) the "addr" 326 */ 327 if (flags & MAP_FIXED) { 328 /* ensure address and file offset are aligned properly */ 329 addr -= pageoff; 330 if (addr & PAGE_MASK) 331 return EINVAL; 332 333 error = range_test(&p->p_vmspace->vm_map, addr, size, true); 334 if (error) { 335 return error; 336 } 337 } else if (addr == 0 || !(flags & MAP_TRYFIXED)) { 338 /* 339 * not fixed: make sure we skip over the largest 340 * possible heap for non-topdown mapping arrangements. 341 * we will refine our guess later (e.g. to account for 342 * VAC, etc) 343 */ 344 345 defaddr = p->p_emul->e_vm_default_addr(p, 346 (vaddr_t)p->p_vmspace->vm_daddr, size, 347 p->p_vmspace->vm_map.flags & VM_MAP_TOPDOWN); 348 349 if (addr == 0 || !(p->p_vmspace->vm_map.flags & VM_MAP_TOPDOWN)) 350 addr = MAX(addr, defaddr); 351 else 352 addr = MIN(addr, defaddr); 353 354 /* 355 * If addr is nonzero and not the default, then the 356 * address is a hint. 357 */ 358 addrhint = (addr != 0 && addr != defaddr); 359 } 360 361 /* 362 * check for file mappings (i.e. not anonymous) and verify file. 363 */ 364 365 advice = UVM_ADV_NORMAL; 366 if ((flags & MAP_ANON) == 0) { 367 KASSERT(size != 0); 368 369 if ((fp = fd_getfile(fd)) == NULL) 370 return EBADF; 371 372 if (fp->f_ops->fo_mmap == NULL) { 373 error = ENODEV; 374 goto out; 375 } 376 error = (*fp->f_ops->fo_mmap)(fp, &pos, size, prot, &flags, 377 &advice, &uobj, &maxprot); 378 if (error) { 379 goto out; 380 } 381 if (uobj == NULL) { 382 flags |= MAP_ANON; 383 fd_putfile(fd); 384 fp = NULL; 385 goto is_anon; 386 } 387 } else { /* MAP_ANON case */ 388 /* 389 * XXX What do we do about (MAP_SHARED|MAP_PRIVATE) == 0? 390 */ 391 if (fd != -1) 392 return EINVAL; 393 394 is_anon: /* label for SunOS style /dev/zero */ 395 uobj = NULL; 396 maxprot = VM_PROT_ALL; 397 pos = 0; 398 } 399 400 maxprot = PAX_MPROTECT_MAXPROTECT(l, prot, extraprot, maxprot); 401 if (((prot | extraprot) & maxprot) != (prot | extraprot)) { 402 error = EACCES; 403 goto out; 404 } 405 if ((error = PAX_MPROTECT_VALIDATE(l, prot))) 406 goto out; 407 408 pax_aslr_mmap(l, &addr, orig_addr, flags); 409 410 /* 411 * Now let kernel internal function uvm_mmap do the work. 412 * 413 * If the user provided a hint, take a reference to uobj in 414 * case the first attempt to satisfy the hint fails, so we can 415 * try again with the default address. 416 */ 417 if (addrhint) { 418 if (uobj) 419 (*uobj->pgops->pgo_reference)(uobj); 420 } 421 error = uvm_mmap(&p->p_vmspace->vm_map, &addr, size, prot, maxprot, 422 flags, advice, uobj, pos, p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur); 423 if (addrhint) { 424 if (error) { 425 addr = defaddr; 426 pax_aslr_mmap(l, &addr, orig_addr, flags); 427 error = uvm_mmap(&p->p_vmspace->vm_map, &addr, size, 428 prot, maxprot, flags, advice, uobj, pos, 429 p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur); 430 } else if (uobj) { 431 /* Release the exta reference we took. */ 432 (*uobj->pgops->pgo_detach)(uobj); 433 } 434 } 435 436 /* remember to add offset */ 437 *retval = (register_t)(addr + pageoff); 438 439 out: 440 if (fp != NULL) 441 fd_putfile(fd); 442 443 return error; 444 } 445 446 /* 447 * sys___msync13: the msync system call (a front-end for flush) 448 */ 449 450 int 451 sys___msync13(struct lwp *l, const struct sys___msync13_args *uap, 452 register_t *retval) 453 { 454 /* { 455 syscallarg(void *) addr; 456 syscallarg(size_t) len; 457 syscallarg(int) flags; 458 } */ 459 struct proc *p = l->l_proc; 460 vaddr_t addr; 461 vsize_t size; 462 struct vm_map *map; 463 int error, flags, uvmflags; 464 bool rv; 465 466 /* 467 * extract syscall args from the uap 468 */ 469 470 addr = (vaddr_t)SCARG(uap, addr); 471 size = (vsize_t)SCARG(uap, len); 472 flags = SCARG(uap, flags); 473 474 /* sanity check flags */ 475 if ((flags & ~(MS_ASYNC | MS_SYNC | MS_INVALIDATE)) != 0 || 476 (flags & (MS_ASYNC | MS_SYNC | MS_INVALIDATE)) == 0 || 477 (flags & (MS_ASYNC | MS_SYNC)) == (MS_ASYNC | MS_SYNC)) 478 return EINVAL; 479 if ((flags & (MS_ASYNC | MS_SYNC)) == 0) 480 flags |= MS_SYNC; 481 482 /* 483 * get map 484 */ 485 map = &p->p_vmspace->vm_map; 486 487 if (round_and_check(map, &addr, &size)) 488 return ENOMEM; 489 490 /* 491 * XXXCDC: do we really need this semantic? 492 * 493 * XXX Gak! If size is zero we are supposed to sync "all modified 494 * pages with the region containing addr". Unfortunately, we 495 * don't really keep track of individual mmaps so we approximate 496 * by flushing the range of the map entry containing addr. 497 * This can be incorrect if the region splits or is coalesced 498 * with a neighbor. 499 */ 500 501 if (size == 0) { 502 struct vm_map_entry *entry; 503 504 vm_map_lock_read(map); 505 rv = uvm_map_lookup_entry(map, addr, &entry); 506 if (rv == true) { 507 addr = entry->start; 508 size = entry->end - entry->start; 509 } 510 vm_map_unlock_read(map); 511 if (rv == false) 512 return EINVAL; 513 } 514 515 /* 516 * translate MS_ flags into PGO_ flags 517 */ 518 519 uvmflags = PGO_CLEANIT; 520 if (flags & MS_INVALIDATE) 521 uvmflags |= PGO_FREE; 522 if (flags & MS_SYNC) 523 uvmflags |= PGO_SYNCIO; 524 525 error = uvm_map_clean(map, addr, addr+size, uvmflags); 526 return error; 527 } 528 529 /* 530 * sys_munmap: unmap a users memory 531 */ 532 533 int 534 sys_munmap(struct lwp *l, const struct sys_munmap_args *uap, register_t *retval) 535 { 536 /* { 537 syscallarg(void *) addr; 538 syscallarg(size_t) len; 539 } */ 540 struct proc *p = l->l_proc; 541 vaddr_t addr; 542 vsize_t size; 543 struct vm_map *map; 544 struct vm_map_entry *dead_entries; 545 546 /* 547 * get syscall args. 548 */ 549 550 addr = (vaddr_t)SCARG(uap, addr); 551 size = (vsize_t)SCARG(uap, len); 552 553 map = &p->p_vmspace->vm_map; 554 555 if (round_and_check(map, &addr, &size)) 556 return EINVAL; 557 558 if (size == 0) 559 return 0; 560 561 vm_map_lock(map); 562 #if 0 563 /* 564 * interesting system call semantic: make sure entire range is 565 * allocated before allowing an unmap. 566 */ 567 if (!uvm_map_checkprot(map, addr, addr + size, VM_PROT_NONE)) { 568 vm_map_unlock(map); 569 return EINVAL; 570 } 571 #endif 572 uvm_unmap_remove(map, addr, addr + size, &dead_entries, 0); 573 vm_map_unlock(map); 574 if (dead_entries != NULL) 575 uvm_unmap_detach(dead_entries, 0); 576 return 0; 577 } 578 579 /* 580 * sys_mprotect: the mprotect system call 581 */ 582 583 int 584 sys_mprotect(struct lwp *l, const struct sys_mprotect_args *uap, 585 register_t *retval) 586 { 587 /* { 588 syscallarg(void *) addr; 589 syscallarg(size_t) len; 590 syscallarg(int) prot; 591 } */ 592 struct proc *p = l->l_proc; 593 vaddr_t addr; 594 vsize_t size; 595 vm_prot_t prot; 596 int error; 597 598 /* 599 * extract syscall args from uap 600 */ 601 602 addr = (vaddr_t)SCARG(uap, addr); 603 size = (vsize_t)SCARG(uap, len); 604 prot = SCARG(uap, prot) & VM_PROT_ALL; 605 606 if (round_and_check(&p->p_vmspace->vm_map, &addr, &size)) 607 return EINVAL; 608 609 error = uvm_map_protect_user(l, addr, addr + size, prot); 610 return error; 611 } 612 613 /* 614 * sys_minherit: the minherit system call 615 */ 616 617 int 618 sys_minherit(struct lwp *l, const struct sys_minherit_args *uap, 619 register_t *retval) 620 { 621 /* { 622 syscallarg(void *) addr; 623 syscallarg(int) len; 624 syscallarg(int) inherit; 625 } */ 626 struct proc *p = l->l_proc; 627 vaddr_t addr; 628 vsize_t size; 629 vm_inherit_t inherit; 630 int error; 631 632 addr = (vaddr_t)SCARG(uap, addr); 633 size = (vsize_t)SCARG(uap, len); 634 inherit = SCARG(uap, inherit); 635 636 if (round_and_check(&p->p_vmspace->vm_map, &addr, &size)) 637 return EINVAL; 638 639 error = uvm_map_inherit(&p->p_vmspace->vm_map, addr, addr + size, 640 inherit); 641 return error; 642 } 643 644 /* 645 * sys_madvise: give advice about memory usage. 646 */ 647 648 /* ARGSUSED */ 649 int 650 sys_madvise(struct lwp *l, const struct sys_madvise_args *uap, 651 register_t *retval) 652 { 653 /* { 654 syscallarg(void *) addr; 655 syscallarg(size_t) len; 656 syscallarg(int) behav; 657 } */ 658 struct proc *p = l->l_proc; 659 vaddr_t addr; 660 vsize_t size; 661 int advice, error; 662 663 addr = (vaddr_t)SCARG(uap, addr); 664 size = (vsize_t)SCARG(uap, len); 665 advice = SCARG(uap, behav); 666 667 if (round_and_check(&p->p_vmspace->vm_map, &addr, &size)) 668 return EINVAL; 669 670 switch (advice) { 671 case MADV_NORMAL: 672 case MADV_RANDOM: 673 case MADV_SEQUENTIAL: 674 error = uvm_map_advice(&p->p_vmspace->vm_map, addr, addr + size, 675 advice); 676 break; 677 678 case MADV_WILLNEED: 679 680 /* 681 * Activate all these pages, pre-faulting them in if 682 * necessary. 683 */ 684 error = uvm_map_willneed(&p->p_vmspace->vm_map, 685 addr, addr + size); 686 break; 687 688 case MADV_DONTNEED: 689 690 /* 691 * Deactivate all these pages. We don't need them 692 * any more. We don't, however, toss the data in 693 * the pages. 694 */ 695 696 error = uvm_map_clean(&p->p_vmspace->vm_map, addr, addr + size, 697 PGO_DEACTIVATE); 698 break; 699 700 case MADV_FREE: 701 702 /* 703 * These pages contain no valid data, and may be 704 * garbage-collected. Toss all resources, including 705 * any swap space in use. 706 */ 707 708 error = uvm_map_clean(&p->p_vmspace->vm_map, addr, addr + size, 709 PGO_FREE); 710 break; 711 712 case MADV_SPACEAVAIL: 713 714 /* 715 * XXXMRG What is this? I think it's: 716 * 717 * Ensure that we have allocated backing-store 718 * for these pages. 719 * 720 * This is going to require changes to the page daemon, 721 * as it will free swap space allocated to pages in core. 722 * There's also what to do for device/file/anonymous memory. 723 */ 724 725 return EINVAL; 726 727 default: 728 return EINVAL; 729 } 730 731 return error; 732 } 733 734 /* 735 * sys_mlock: memory lock 736 */ 737 738 int 739 sys_mlock(struct lwp *l, const struct sys_mlock_args *uap, register_t *retval) 740 { 741 /* { 742 syscallarg(const void *) addr; 743 syscallarg(size_t) len; 744 } */ 745 struct proc *p = l->l_proc; 746 vaddr_t addr; 747 vsize_t size; 748 int error; 749 750 /* 751 * extract syscall args from uap 752 */ 753 754 addr = (vaddr_t)SCARG(uap, addr); 755 size = (vsize_t)SCARG(uap, len); 756 757 if (round_and_check(&p->p_vmspace->vm_map, &addr, &size)) 758 return ENOMEM; 759 760 if (atop(size) + uvmexp.wired > uvmexp.wiredmax) 761 return EAGAIN; 762 763 if (size + ptoa(pmap_wired_count(vm_map_pmap(&p->p_vmspace->vm_map))) > 764 p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur) 765 return EAGAIN; 766 767 error = uvm_map_pageable(&p->p_vmspace->vm_map, addr, addr+size, false, 768 0); 769 if (error == EFAULT) 770 error = ENOMEM; 771 return error; 772 } 773 774 /* 775 * sys_munlock: unlock wired pages 776 */ 777 778 int 779 sys_munlock(struct lwp *l, const struct sys_munlock_args *uap, 780 register_t *retval) 781 { 782 /* { 783 syscallarg(const void *) addr; 784 syscallarg(size_t) len; 785 } */ 786 struct proc *p = l->l_proc; 787 vaddr_t addr; 788 vsize_t size; 789 790 /* 791 * extract syscall args from uap 792 */ 793 794 addr = (vaddr_t)SCARG(uap, addr); 795 size = (vsize_t)SCARG(uap, len); 796 797 if (round_and_check(&p->p_vmspace->vm_map, &addr, &size)) 798 return ENOMEM; 799 800 if (uvm_map_pageable(&p->p_vmspace->vm_map, addr, addr+size, true, 0)) 801 return ENOMEM; 802 803 return 0; 804 } 805 806 /* 807 * sys_mlockall: lock all pages mapped into an address space. 808 */ 809 810 int 811 sys_mlockall(struct lwp *l, const struct sys_mlockall_args *uap, 812 register_t *retval) 813 { 814 /* { 815 syscallarg(int) flags; 816 } */ 817 struct proc *p = l->l_proc; 818 int error, flags; 819 820 flags = SCARG(uap, flags); 821 822 if (flags == 0 || (flags & ~(MCL_CURRENT|MCL_FUTURE)) != 0) 823 return EINVAL; 824 825 error = uvm_map_pageable_all(&p->p_vmspace->vm_map, flags, 826 p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur); 827 return error; 828 } 829 830 /* 831 * sys_munlockall: unlock all pages mapped into an address space. 832 */ 833 834 int 835 sys_munlockall(struct lwp *l, const void *v, register_t *retval) 836 { 837 struct proc *p = l->l_proc; 838 839 (void) uvm_map_pageable_all(&p->p_vmspace->vm_map, 0, 0); 840 return 0; 841 } 842 843 /* 844 * uvm_mmap: internal version of mmap 845 * 846 * - used by sys_mmap and various framebuffers 847 * - uobj is a struct uvm_object pointer or NULL for MAP_ANON 848 * - caller must page-align the file offset 849 * 850 * XXX This appears to leak the uobj in various error branches? Need 851 * to clean up the contract around uobj reference. 852 */ 853 854 static int 855 uvm_mmap(struct vm_map *map, vaddr_t *addr, vsize_t size, vm_prot_t prot, 856 vm_prot_t maxprot, int flags, int advice, struct uvm_object *uobj, 857 voff_t foff, vsize_t locklimit) 858 { 859 vaddr_t align = 0; 860 int error; 861 uvm_flag_t uvmflag = 0; 862 863 /* 864 * check params 865 */ 866 867 if (size == 0) 868 return 0; 869 if (foff & PAGE_MASK) 870 return EINVAL; 871 if ((prot & maxprot) != prot) 872 return EINVAL; 873 874 /* 875 * for non-fixed mappings, round off the suggested address. 876 * for fixed mappings, check alignment. 877 */ 878 879 if ((flags & MAP_FIXED) == 0) { 880 *addr = round_page(*addr); 881 } else { 882 if (*addr & PAGE_MASK) 883 return EINVAL; 884 uvmflag |= UVM_FLAG_FIXED | UVM_FLAG_UNMAP; 885 } 886 887 /* 888 * Try to see if any requested alignment can even be attemped. 889 * Make sure we can express the alignment (asking for a >= 4GB 890 * alignment on an ILP32 architecture make no sense) and the 891 * alignment is at least for a page sized quanitiy. If the 892 * request was for a fixed mapping, make sure supplied address 893 * adheres to the request alignment. 894 */ 895 align = (flags & MAP_ALIGNMENT_MASK) >> MAP_ALIGNMENT_SHIFT; 896 if (align) { 897 if (align >= sizeof(vaddr_t) * NBBY) 898 return EINVAL; 899 align = 1UL << align; 900 if (align < PAGE_SIZE) 901 return EINVAL; 902 if (align >= vm_map_max(map)) 903 return ENOMEM; 904 if (flags & MAP_FIXED) { 905 if ((*addr & (align-1)) != 0) 906 return EINVAL; 907 align = 0; 908 } 909 } 910 911 /* 912 * check resource limits 913 */ 914 915 if (!VM_MAP_IS_KERNEL(map) && 916 (((rlim_t)curproc->p_vmspace->vm_map.size + (rlim_t)size) > 917 curproc->p_rlimit[RLIMIT_AS].rlim_cur)) 918 return ENOMEM; 919 920 /* 921 * handle anon vs. non-anon mappings. for non-anon mappings attach 922 * to underlying vm object. 923 */ 924 925 if (flags & MAP_ANON) { 926 KASSERT(uobj == NULL); 927 foff = UVM_UNKNOWN_OFFSET; 928 if ((flags & MAP_SHARED) == 0) 929 /* XXX: defer amap create */ 930 uvmflag |= UVM_FLAG_COPYONW; 931 else 932 /* shared: create amap now */ 933 uvmflag |= UVM_FLAG_OVERLAY; 934 935 } else { 936 KASSERT(uobj != NULL); 937 if ((flags & MAP_SHARED) == 0) { 938 uvmflag |= UVM_FLAG_COPYONW; 939 } 940 } 941 942 uvmflag = UVM_MAPFLAG(prot, maxprot, 943 (flags & MAP_SHARED) ? UVM_INH_SHARE : UVM_INH_COPY, advice, 944 uvmflag); 945 error = uvm_map(map, addr, size, uobj, foff, align, uvmflag); 946 if (error) { 947 if (uobj) 948 uobj->pgops->pgo_detach(uobj); 949 return error; 950 } 951 952 /* 953 * POSIX 1003.1b -- if our address space was configured 954 * to lock all future mappings, wire the one we just made. 955 * 956 * Also handle the MAP_WIRED flag here. 957 */ 958 959 if (prot == VM_PROT_NONE) { 960 961 /* 962 * No more work to do in this case. 963 */ 964 965 return 0; 966 } 967 if ((flags & MAP_WIRED) != 0 || (map->flags & VM_MAP_WIREFUTURE) != 0) { 968 vm_map_lock(map); 969 if (atop(size) + uvmexp.wired > uvmexp.wiredmax || 970 (locklimit != 0 && 971 size + ptoa(pmap_wired_count(vm_map_pmap(map))) > 972 locklimit)) { 973 vm_map_unlock(map); 974 uvm_unmap(map, *addr, *addr + size); 975 return ENOMEM; 976 } 977 978 /* 979 * uvm_map_pageable() always returns the map unlocked. 980 */ 981 982 error = uvm_map_pageable(map, *addr, *addr + size, 983 false, UVM_LK_ENTER); 984 if (error) { 985 uvm_unmap(map, *addr, *addr + size); 986 return error; 987 } 988 return 0; 989 } 990 return 0; 991 } 992 993 vaddr_t 994 uvm_default_mapaddr(struct proc *p, vaddr_t base, vsize_t sz, int topdown) 995 { 996 997 if (topdown) 998 return VM_DEFAULT_ADDRESS_TOPDOWN(base, sz); 999 else 1000 return VM_DEFAULT_ADDRESS_BOTTOMUP(base, sz); 1001 } 1002 1003 int 1004 uvm_mmap_dev(struct proc *p, void **addrp, size_t len, dev_t dev, 1005 off_t off) 1006 { 1007 struct uvm_object *uobj; 1008 int error, flags, prot; 1009 1010 KASSERT(len > 0); 1011 1012 flags = MAP_SHARED; 1013 prot = VM_PROT_READ | VM_PROT_WRITE; 1014 if (*addrp) 1015 flags |= MAP_FIXED; 1016 else 1017 *addrp = (void *)p->p_emul->e_vm_default_addr(p, 1018 (vaddr_t)p->p_vmspace->vm_daddr, len, 1019 p->p_vmspace->vm_map.flags & VM_MAP_TOPDOWN); 1020 1021 uobj = udv_attach(dev, prot, off, len); 1022 if (uobj == NULL) 1023 return EINVAL; 1024 1025 error = uvm_mmap(&p->p_vmspace->vm_map, (vaddr_t *)addrp, 1026 (vsize_t)len, prot, prot, flags, UVM_ADV_RANDOM, uobj, off, 1027 p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur); 1028 return error; 1029 } 1030 1031 int 1032 uvm_mmap_anon(struct proc *p, void **addrp, size_t len) 1033 { 1034 int error, flags, prot; 1035 1036 flags = MAP_PRIVATE | MAP_ANON; 1037 prot = VM_PROT_READ | VM_PROT_WRITE; 1038 if (*addrp) 1039 flags |= MAP_FIXED; 1040 else 1041 *addrp = (void *)p->p_emul->e_vm_default_addr(p, 1042 (vaddr_t)p->p_vmspace->vm_daddr, len, 1043 p->p_vmspace->vm_map.flags & VM_MAP_TOPDOWN); 1044 1045 error = uvm_mmap(&p->p_vmspace->vm_map, (vaddr_t *)addrp, 1046 (vsize_t)len, prot, prot, flags, UVM_ADV_NORMAL, NULL, 0, 1047 p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur); 1048 return error; 1049 } 1050
Indexes created Sat Sep 20 22:09:52 GMT 2025