1 /* 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * The Mach Operating System project at Carnegie-Mellon University. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. 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. 23 * 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 34 * SUCH DAMAGE. 35 * 36 * from: @(#)vm_map.c 8.3 (Berkeley) 1/12/94 37 * 38 * 39 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 40 * All rights reserved. 41 * 42 * Authors: Avadis Tevanian, Jr., Michael Wayne Young 43 * 44 * Permission to use, copy, modify and distribute this software and 45 * its documentation is hereby granted, provided that both the copyright 46 * notice and this permission notice appear in all copies of the 47 * software, derivative works or modified versions, and any portions 48 * thereof, and that both notices appear in supporting documentation. 49 * 50 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 51 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 52 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 53 * 54 * Carnegie Mellon requests users of this software to return to 55 * 56 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 57 * School of Computer Science 58 * Carnegie Mellon University 59 * Pittsburgh PA 15213-3890 60 * 61 * any improvements or extensions that they make and grant Carnegie the 62 * rights to redistribute these changes. 63 * 64 * $FreeBSD$ 65 */ 66 67 /* 68 * Virtual memory mapping module. 69 */ 70 71 #include <sys/param.h> 72 #include <sys/systm.h> 73 #include <sys/ktr.h> 74 #include <sys/lock.h> 75 #include <sys/mutex.h> 76 #include <sys/proc.h> 77 #include <sys/vmmeter.h> 78 #include <sys/mman.h> 79 #include <sys/vnode.h> 80 #include <sys/resourcevar.h> 81 #include <sys/sysent.h> 82 #include <sys/stdint.h> 83 84 #include <vm/vm.h> 85 #include <vm/vm_param.h> 86 #include <vm/pmap.h> 87 #include <vm/vm_map.h> 88 #include <vm/vm_page.h> 89 #include <vm/vm_object.h> 90 #include <vm/vm_pager.h> 91 #include <vm/vm_kern.h> 92 #include <vm/vm_extern.h> 93 #include <vm/swap_pager.h> 94 #include <vm/uma.h> 95 96 /* 97 * Virtual memory maps provide for the mapping, protection, 98 * and sharing of virtual memory objects. In addition, 99 * this module provides for an efficient virtual copy of 100 * memory from one map to another. 101 * 102 * Synchronization is required prior to most operations. 103 * 104 * Maps consist of an ordered doubly-linked list of simple 105 * entries; a single hint is used to speed up lookups. 106 * 107 * Since portions of maps are specified by start/end addresses, 108 * which may not align with existing map entries, all 109 * routines merely "clip" entries to these start/end values. 110 * [That is, an entry is split into two, bordering at a 111 * start or end value.] Note that these clippings may not 112 * always be necessary (as the two resulting entries are then 113 * not changed); however, the clipping is done for convenience. 114 * 115 * As mentioned above, virtual copy operations are performed 116 * by copying VM object references from one map to 117 * another, and then marking both regions as copy-on-write. 118 */ 119 120 /* 121 * vm_map_startup: 122 * 123 * Initialize the vm_map module. Must be called before 124 * any other vm_map routines. 125 * 126 * Map and entry structures are allocated from the general 127 * purpose memory pool with some exceptions: 128 * 129 * - The kernel map and kmem submap are allocated statically. 130 * - Kernel map entries are allocated out of a static pool. 131 * 132 * These restrictions are necessary since malloc() uses the 133 * maps and requires map entries. 134 */ 135 136 static struct mtx map_sleep_mtx; 137 static uma_zone_t mapentzone; 138 static uma_zone_t kmapentzone; 139 static uma_zone_t mapzone; 140 static uma_zone_t vmspace_zone; 141 static struct vm_object kmapentobj; 142 static void vmspace_zinit(void *mem, int size); 143 static void vmspace_zfini(void *mem, int size); 144 static void vm_map_zinit(void *mem, int size); 145 static void vm_map_zfini(void *mem, int size); 146 static void _vm_map_init(vm_map_t map, vm_offset_t min, vm_offset_t max); 147 148 #ifdef INVARIANTS 149 static void vm_map_zdtor(void *mem, int size, void *arg); 150 static void vmspace_zdtor(void *mem, int size, void *arg); 151 #endif 152 153 void 154 vm_map_startup(void) 155 { 156 mtx_init(&map_sleep_mtx, "vm map sleep mutex", NULL, MTX_DEF); 157 mapzone = uma_zcreate("MAP", sizeof(struct vm_map), NULL, 158 #ifdef INVARIANTS 159 vm_map_zdtor, 160 #else 161 NULL, 162 #endif 163 vm_map_zinit, vm_map_zfini, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 164 uma_prealloc(mapzone, MAX_KMAP); 165 kmapentzone = uma_zcreate("KMAP ENTRY", sizeof(struct vm_map_entry), 166 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 167 UMA_ZONE_MTXCLASS | UMA_ZONE_VM); 168 uma_prealloc(kmapentzone, MAX_KMAPENT); 169 mapentzone = uma_zcreate("MAP ENTRY", sizeof(struct vm_map_entry), 170 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 171 uma_prealloc(mapentzone, MAX_MAPENT); 172 } 173 174 static void 175 vmspace_zfini(void *mem, int size) 176 { 177 struct vmspace *vm; 178 179 vm = (struct vmspace *)mem; 180 181 vm_map_zfini(&vm->vm_map, sizeof(vm->vm_map)); 182 } 183 184 static void 185 vmspace_zinit(void *mem, int size) 186 { 187 struct vmspace *vm; 188 189 vm = (struct vmspace *)mem; 190 191 vm_map_zinit(&vm->vm_map, sizeof(vm->vm_map)); 192 } 193 194 static void 195 vm_map_zfini(void *mem, int size) 196 { 197 vm_map_t map; 198 199 map = (vm_map_t)mem; 200 mtx_destroy(&map->system_mtx); 201 lockdestroy(&map->lock); 202 } 203 204 static void 205 vm_map_zinit(void *mem, int size) 206 { 207 vm_map_t map; 208 209 map = (vm_map_t)mem; 210 map->nentries = 0; 211 map->size = 0; 212 map->infork = 0; 213 mtx_init(&map->system_mtx, "system map", NULL, MTX_DEF); 214 lockinit(&map->lock, PVM, "thrd_sleep", 0, LK_NOPAUSE); 215 } 216 217 #ifdef INVARIANTS 218 static void 219 vmspace_zdtor(void *mem, int size, void *arg) 220 { 221 struct vmspace *vm; 222 223 vm = (struct vmspace *)mem; 224 225 vm_map_zdtor(&vm->vm_map, sizeof(vm->vm_map), arg); 226 } 227 static void 228 vm_map_zdtor(void *mem, int size, void *arg) 229 { 230 vm_map_t map; 231 232 map = (vm_map_t)mem; 233 KASSERT(map->nentries == 0, 234 ("map %p nentries == %d on free.", 235 map, map->nentries)); 236 KASSERT(map->size == 0, 237 ("map %p size == %lu on free.", 238 map, (unsigned long)map->size)); 239 KASSERT(map->infork == 0, 240 ("map %p infork == %d on free.", 241 map, map->infork)); 242 } 243 #endif /* INVARIANTS */ 244 245 /* 246 * Allocate a vmspace structure, including a vm_map and pmap, 247 * and initialize those structures. The refcnt is set to 1. 248 * The remaining fields must be initialized by the caller. 249 */ 250 struct vmspace * 251 vmspace_alloc(min, max) 252 vm_offset_t min, max; 253 { 254 struct vmspace *vm; 255 256 GIANT_REQUIRED; 257 vm = uma_zalloc(vmspace_zone, M_WAITOK); 258 CTR1(KTR_VM, "vmspace_alloc: %p", vm); 259 _vm_map_init(&vm->vm_map, min, max); 260 pmap_pinit(vmspace_pmap(vm)); 261 vm->vm_map.pmap = vmspace_pmap(vm); /* XXX */ 262 vm->vm_refcnt = 1; 263 vm->vm_shm = NULL; 264 vm->vm_exitingcnt = 0; 265 return (vm); 266 } 267 268 void 269 vm_init2(void) 270 { 271 uma_zone_set_obj(kmapentzone, &kmapentobj, lmin(cnt.v_page_count, 272 (VM_MAX_KERNEL_ADDRESS - KERNBASE) / PAGE_SIZE) / 8); 273 vmspace_zone = uma_zcreate("VMSPACE", sizeof(struct vmspace), NULL, 274 #ifdef INVARIANTS 275 vmspace_zdtor, 276 #else 277 NULL, 278 #endif 279 vmspace_zinit, vmspace_zfini, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 280 pmap_init2(); 281 } 282 283 static __inline void 284 vmspace_dofree(struct vmspace *vm) 285 { 286 CTR1(KTR_VM, "vmspace_free: %p", vm); 287 /* 288 * Lock the map, to wait out all other references to it. 289 * Delete all of the mappings and pages they hold, then call 290 * the pmap module to reclaim anything left. 291 */ 292 vm_map_lock(&vm->vm_map); 293 (void) vm_map_delete(&vm->vm_map, vm->vm_map.min_offset, 294 vm->vm_map.max_offset); 295 vm_map_unlock(&vm->vm_map); 296 297 pmap_release(vmspace_pmap(vm)); 298 uma_zfree(vmspace_zone, vm); 299 } 300 301 void 302 vmspace_free(struct vmspace *vm) 303 { 304 GIANT_REQUIRED; 305 306 if (vm->vm_refcnt == 0) 307 panic("vmspace_free: attempt to free already freed vmspace"); 308 309 if (--vm->vm_refcnt == 0 && vm->vm_exitingcnt == 0) 310 vmspace_dofree(vm); 311 } 312 313 void 314 vmspace_exitfree(struct proc *p) 315 { 316 struct vmspace *vm; 317 318 GIANT_REQUIRED; 319 vm = p->p_vmspace; 320 p->p_vmspace = NULL; 321 322 /* 323 * cleanup by parent process wait()ing on exiting child. vm_refcnt 324 * may not be 0 (e.g. fork() and child exits without exec()ing). 325 * exitingcnt may increment above 0 and drop back down to zero 326 * several times while vm_refcnt is held non-zero. vm_refcnt 327 * may also increment above 0 and drop back down to zero several 328 * times while vm_exitingcnt is held non-zero. 329 * 330 * The last wait on the exiting child's vmspace will clean up 331 * the remainder of the vmspace. 332 */ 333 if (--vm->vm_exitingcnt == 0 && vm->vm_refcnt == 0) 334 vmspace_dofree(vm); 335 } 336 337 /* 338 * vmspace_swap_count() - count the approximate swap useage in pages for a 339 * vmspace. 340 * 341 * Swap useage is determined by taking the proportional swap used by 342 * VM objects backing the VM map. To make up for fractional losses, 343 * if the VM object has any swap use at all the associated map entries 344 * count for at least 1 swap page. 345 */ 346 int 347 vmspace_swap_count(struct vmspace *vmspace) 348 { 349 vm_map_t map = &vmspace->vm_map; 350 vm_map_entry_t cur; 351 int count = 0; 352 353 vm_map_lock_read(map); 354 for (cur = map->header.next; cur != &map->header; cur = cur->next) { 355 vm_object_t object; 356 357 if ((cur->eflags & MAP_ENTRY_IS_SUB_MAP) == 0 && 358 (object = cur->object.vm_object) != NULL && 359 object->type == OBJT_SWAP 360 ) { 361 int n = (cur->end - cur->start) / PAGE_SIZE; 362 363 if (object->un_pager.swp.swp_bcount) { 364 count += object->un_pager.swp.swp_bcount * 365 SWAP_META_PAGES * n / object->size + 1; 366 } 367 } 368 } 369 vm_map_unlock_read(map); 370 return (count); 371 } 372 373 void 374 _vm_map_lock(vm_map_t map, const char *file, int line) 375 { 376 int error; 377 378 if (map->system_map) 379 _mtx_lock_flags(&map->system_mtx, 0, file, line); 380 else { 381 error = lockmgr(&map->lock, LK_EXCLUSIVE, NULL, curthread); 382 KASSERT(error == 0, ("%s: failed to get lock", __func__)); 383 } 384 map->timestamp++; 385 } 386 387 void 388 _vm_map_unlock(vm_map_t map, const char *file, int line) 389 { 390 391 if (map->system_map) 392 _mtx_unlock_flags(&map->system_mtx, 0, file, line); 393 else 394 lockmgr(&map->lock, LK_RELEASE, NULL, curthread); 395 } 396 397 void 398 _vm_map_lock_read(vm_map_t map, const char *file, int line) 399 { 400 int error; 401 402 if (map->system_map) 403 _mtx_lock_flags(&map->system_mtx, 0, file, line); 404 else { 405 error = lockmgr(&map->lock, LK_EXCLUSIVE, NULL, curthread); 406 KASSERT(error == 0, ("%s: failed to get lock", __func__)); 407 } 408 } 409 410 void 411 _vm_map_unlock_read(vm_map_t map, const char *file, int line) 412 { 413 414 if (map->system_map) 415 _mtx_unlock_flags(&map->system_mtx, 0, file, line); 416 else 417 lockmgr(&map->lock, LK_RELEASE, NULL, curthread); 418 } 419 420 int 421 _vm_map_trylock(vm_map_t map, const char *file, int line) 422 { 423 int error; 424 425 error = map->system_map ? 426 !_mtx_trylock(&map->system_mtx, 0, file, line) : 427 lockmgr(&map->lock, LK_EXCLUSIVE | LK_NOWAIT, NULL, curthread); 428 if (error == 0) 429 map->timestamp++; 430 return (error == 0); 431 } 432 433 int 434 _vm_map_lock_upgrade(vm_map_t map, const char *file, int line) 435 { 436 437 if (map->system_map) { 438 #ifdef INVARIANTS 439 _mtx_assert(&map->system_mtx, MA_OWNED, file, line); 440 #endif 441 } else 442 KASSERT(lockstatus(&map->lock, curthread) == LK_EXCLUSIVE, 443 ("%s: lock not held", __func__)); 444 map->timestamp++; 445 return (0); 446 } 447 448 void 449 _vm_map_lock_downgrade(vm_map_t map, const char *file, int line) 450 { 451 452 if (map->system_map) { 453 #ifdef INVARIANTS 454 _mtx_assert(&map->system_mtx, MA_OWNED, file, line); 455 #endif 456 } else 457 KASSERT(lockstatus(&map->lock, curthread) == LK_EXCLUSIVE, 458 ("%s: lock not held", __func__)); 459 } 460 461 /* 462 * vm_map_unlock_and_wait: 463 */ 464 int 465 vm_map_unlock_and_wait(vm_map_t map, boolean_t user_wait) 466 { 467 468 mtx_lock(&map_sleep_mtx); 469 vm_map_unlock(map); 470 return (msleep(&map->root, &map_sleep_mtx, PDROP | PVM, "vmmaps", 0)); 471 } 472 473 /* 474 * vm_map_wakeup: 475 */ 476 void 477 vm_map_wakeup(vm_map_t map) 478 { 479 480 /* 481 * Acquire and release map_sleep_mtx to prevent a wakeup() 482 * from being performed (and lost) between the vm_map_unlock() 483 * and the msleep() in vm_map_unlock_and_wait(). 484 */ 485 mtx_lock(&map_sleep_mtx); 486 mtx_unlock(&map_sleep_mtx); 487 wakeup(&map->root); 488 } 489 490 long 491 vmspace_resident_count(struct vmspace *vmspace) 492 { 493 return pmap_resident_count(vmspace_pmap(vmspace)); 494 } 495 496 /* 497 * vm_map_create: 498 * 499 * Creates and returns a new empty VM map with 500 * the given physical map structure, and having 501 * the given lower and upper address bounds. 502 */ 503 vm_map_t 504 vm_map_create(pmap_t pmap, vm_offset_t min, vm_offset_t max) 505 { 506 vm_map_t result; 507 508 result = uma_zalloc(mapzone, M_WAITOK); 509 CTR1(KTR_VM, "vm_map_create: %p", result); 510 _vm_map_init(result, min, max); 511 result->pmap = pmap; 512 return (result); 513 } 514 515 /* 516 * Initialize an existing vm_map structure 517 * such as that in the vmspace structure. 518 * The pmap is set elsewhere. 519 */ 520 static void 521 _vm_map_init(vm_map_t map, vm_offset_t min, vm_offset_t max) 522 { 523 524 map->header.next = map->header.prev = &map->header; 525 map->needs_wakeup = FALSE; 526 map->system_map = 0; 527 map->min_offset = min; 528 map->max_offset = max; 529 map->first_free = &map->header; 530 map->root = NULL; 531 map->timestamp = 0; 532 } 533 534 void 535 vm_map_init(vm_map_t map, vm_offset_t min, vm_offset_t max) 536 { 537 _vm_map_init(map, min, max); 538 mtx_init(&map->system_mtx, "system map", NULL, MTX_DEF); 539 lockinit(&map->lock, PVM, "thrd_sleep", 0, LK_NOPAUSE); 540 } 541 542 /* 543 * vm_map_entry_dispose: [ internal use only ] 544 * 545 * Inverse of vm_map_entry_create. 546 */ 547 static void 548 vm_map_entry_dispose(vm_map_t map, vm_map_entry_t entry) 549 { 550 uma_zfree(map->system_map ? kmapentzone : mapentzone, entry); 551 } 552 553 /* 554 * vm_map_entry_create: [ internal use only ] 555 * 556 * Allocates a VM map entry for insertion. 557 * No entry fields are filled in. 558 */ 559 static vm_map_entry_t 560 vm_map_entry_create(vm_map_t map) 561 { 562 vm_map_entry_t new_entry; 563 564 if (map->system_map) 565 new_entry = uma_zalloc(kmapentzone, M_NOWAIT); 566 else 567 new_entry = uma_zalloc(mapentzone, M_WAITOK); 568 if (new_entry == NULL) 569 panic("vm_map_entry_create: kernel resources exhausted"); 570 return (new_entry); 571 } 572 573 /* 574 * vm_map_entry_set_behavior: 575 * 576 * Set the expected access behavior, either normal, random, or 577 * sequential. 578 */ 579 static __inline void 580 vm_map_entry_set_behavior(vm_map_entry_t entry, u_char behavior) 581 { 582 entry->eflags = (entry->eflags & ~MAP_ENTRY_BEHAV_MASK) | 583 (behavior & MAP_ENTRY_BEHAV_MASK); 584 } 585 586 /* 587 * vm_map_entry_splay: 588 * 589 * Implements Sleator and Tarjan's top-down splay algorithm. Returns 590 * the vm_map_entry containing the given address. If, however, that 591 * address is not found in the vm_map, returns a vm_map_entry that is 592 * adjacent to the address, coming before or after it. 593 */ 594 static vm_map_entry_t 595 vm_map_entry_splay(vm_offset_t address, vm_map_entry_t root) 596 { 597 struct vm_map_entry dummy; 598 vm_map_entry_t lefttreemax, righttreemin, y; 599 600 if (root == NULL) 601 return (root); 602 lefttreemax = righttreemin = &dummy; 603 for (;; root = y) { 604 if (address < root->start) { 605 if ((y = root->left) == NULL) 606 break; 607 if (address < y->start) { 608 /* Rotate right. */ 609 root->left = y->right; 610 y->right = root; 611 root = y; 612 if ((y = root->left) == NULL) 613 break; 614 } 615 /* Link into the new root's right tree. */ 616 righttreemin->left = root; 617 righttreemin = root; 618 } else if (address >= root->end) { 619 if ((y = root->right) == NULL) 620 break; 621 if (address >= y->end) { 622 /* Rotate left. */ 623 root->right = y->left; 624 y->left = root; 625 root = y; 626 if ((y = root->right) == NULL) 627 break; 628 } 629 /* Link into the new root's left tree. */ 630 lefttreemax->right = root; 631 lefttreemax = root; 632 } else 633 break; 634 } 635 /* Assemble the new root. */ 636 lefttreemax->right = root->left; 637 righttreemin->left = root->right; 638 root->left = dummy.right; 639 root->right = dummy.left; 640 return (root); 641 } 642 643 /* 644 * vm_map_entry_{un,}link: 645 * 646 * Insert/remove entries from maps. 647 */ 648 static void 649 vm_map_entry_link(vm_map_t map, 650 vm_map_entry_t after_where, 651 vm_map_entry_t entry) 652 { 653 654 CTR4(KTR_VM, 655 "vm_map_entry_link: map %p, nentries %d, entry %p, after %p", map, 656 map->nentries, entry, after_where); 657 map->nentries++; 658 entry->prev = after_where; 659 entry->next = after_where->next; 660 entry->next->prev = entry; 661 after_where->next = entry; 662 663 if (after_where != &map->header) { 664 if (after_where != map->root) 665 vm_map_entry_splay(after_where->start, map->root); 666 entry->right = after_where->right; 667 entry->left = after_where; 668 after_where->right = NULL; 669 } else { 670 entry->right = map->root; 671 entry->left = NULL; 672 } 673 map->root = entry; 674 } 675 676 static void 677 vm_map_entry_unlink(vm_map_t map, 678 vm_map_entry_t entry) 679 { 680 vm_map_entry_t next, prev, root; 681 682 if (entry != map->root) 683 vm_map_entry_splay(entry->start, map->root); 684 if (entry->left == NULL) 685 root = entry->right; 686 else { 687 root = vm_map_entry_splay(entry->start, entry->left); 688 root->right = entry->right; 689 } 690 map->root = root; 691 692 prev = entry->prev; 693 next = entry->next; 694 next->prev = prev; 695 prev->next = next; 696 map->nentries--; 697 CTR3(KTR_VM, "vm_map_entry_unlink: map %p, nentries %d, entry %p", map, 698 map->nentries, entry); 699 } 700 701 /* 702 * vm_map_lookup_entry: [ internal use only ] 703 * 704 * Finds the map entry containing (or 705 * immediately preceding) the specified address 706 * in the given map; the entry is returned 707 * in the "entry" parameter. The boolean 708 * result indicates whether the address is 709 * actually contained in the map. 710 */ 711 boolean_t 712 vm_map_lookup_entry( 713 vm_map_t map, 714 vm_offset_t address, 715 vm_map_entry_t *entry) /* OUT */ 716 { 717 vm_map_entry_t cur; 718 719 cur = vm_map_entry_splay(address, map->root); 720 if (cur == NULL) 721 *entry = &map->header; 722 else { 723 map->root = cur; 724 725 if (address >= cur->start) { 726 *entry = cur; 727 if (cur->end > address) 728 return (TRUE); 729 } else 730 *entry = cur->prev; 731 } 732 return (FALSE); 733 } 734 735 /* 736 * vm_map_insert: 737 * 738 * Inserts the given whole VM object into the target 739 * map at the specified address range. The object's 740 * size should match that of the address range. 741 * 742 * Requires that the map be locked, and leaves it so. 743 * 744 * If object is non-NULL, ref count must be bumped by caller 745 * prior to making call to account for the new entry. 746 */ 747 int 748 vm_map_insert(vm_map_t map, vm_object_t object, vm_ooffset_t offset, 749 vm_offset_t start, vm_offset_t end, vm_prot_t prot, vm_prot_t max, 750 int cow) 751 { 752 vm_map_entry_t new_entry; 753 vm_map_entry_t prev_entry; 754 vm_map_entry_t temp_entry; 755 vm_eflags_t protoeflags; 756 757 /* 758 * Check that the start and end points are not bogus. 759 */ 760 if ((start < map->min_offset) || (end > map->max_offset) || 761 (start >= end)) 762 return (KERN_INVALID_ADDRESS); 763 764 /* 765 * Find the entry prior to the proposed starting address; if it's part 766 * of an existing entry, this range is bogus. 767 */ 768 if (vm_map_lookup_entry(map, start, &temp_entry)) 769 return (KERN_NO_SPACE); 770 771 prev_entry = temp_entry; 772 773 /* 774 * Assert that the next entry doesn't overlap the end point. 775 */ 776 if ((prev_entry->next != &map->header) && 777 (prev_entry->next->start < end)) 778 return (KERN_NO_SPACE); 779 780 protoeflags = 0; 781 782 if (cow & MAP_COPY_ON_WRITE) 783 protoeflags |= MAP_ENTRY_COW|MAP_ENTRY_NEEDS_COPY; 784 785 if (cow & MAP_NOFAULT) { 786 protoeflags |= MAP_ENTRY_NOFAULT; 787 788 KASSERT(object == NULL, 789 ("vm_map_insert: paradoxical MAP_NOFAULT request")); 790 } 791 if (cow & MAP_DISABLE_SYNCER) 792 protoeflags |= MAP_ENTRY_NOSYNC; 793 if (cow & MAP_DISABLE_COREDUMP) 794 protoeflags |= MAP_ENTRY_NOCOREDUMP; 795 796 if (object) { 797 /* 798 * When object is non-NULL, it could be shared with another 799 * process. We have to set or clear OBJ_ONEMAPPING 800 * appropriately. 801 */ 802 vm_object_lock(object); 803 if ((object->ref_count > 1) || (object->shadow_count != 0)) { 804 vm_object_clear_flag(object, OBJ_ONEMAPPING); 805 } 806 vm_object_unlock(object); 807 } 808 else if ((prev_entry != &map->header) && 809 (prev_entry->eflags == protoeflags) && 810 (prev_entry->end == start) && 811 (prev_entry->wired_count == 0) && 812 ((prev_entry->object.vm_object == NULL) || 813 vm_object_coalesce(prev_entry->object.vm_object, 814 OFF_TO_IDX(prev_entry->offset), 815 (vm_size_t)(prev_entry->end - prev_entry->start), 816 (vm_size_t)(end - prev_entry->end)))) { 817 /* 818 * We were able to extend the object. Determine if we 819 * can extend the previous map entry to include the 820 * new range as well. 821 */ 822 if ((prev_entry->inheritance == VM_INHERIT_DEFAULT) && 823 (prev_entry->protection == prot) && 824 (prev_entry->max_protection == max)) { 825 map->size += (end - prev_entry->end); 826 prev_entry->end = end; 827 vm_map_simplify_entry(map, prev_entry); 828 return (KERN_SUCCESS); 829 } 830 831 /* 832 * If we can extend the object but cannot extend the 833 * map entry, we have to create a new map entry. We 834 * must bump the ref count on the extended object to 835 * account for it. object may be NULL. 836 */ 837 object = prev_entry->object.vm_object; 838 offset = prev_entry->offset + 839 (prev_entry->end - prev_entry->start); 840 vm_object_reference(object); 841 } 842 843 /* 844 * NOTE: if conditionals fail, object can be NULL here. This occurs 845 * in things like the buffer map where we manage kva but do not manage 846 * backing objects. 847 */ 848 849 /* 850 * Create a new entry 851 */ 852 new_entry = vm_map_entry_create(map); 853 new_entry->start = start; 854 new_entry->end = end; 855 856 new_entry->eflags = protoeflags; 857 new_entry->object.vm_object = object; 858 new_entry->offset = offset; 859 new_entry->avail_ssize = 0; 860 861 new_entry->inheritance = VM_INHERIT_DEFAULT; 862 new_entry->protection = prot; 863 new_entry->max_protection = max; 864 new_entry->wired_count = 0; 865 866 /* 867 * Insert the new entry into the list 868 */ 869 vm_map_entry_link(map, prev_entry, new_entry); 870 map->size += new_entry->end - new_entry->start; 871 872 /* 873 * Update the free space hint 874 */ 875 if ((map->first_free == prev_entry) && 876 (prev_entry->end >= new_entry->start)) { 877 map->first_free = new_entry; 878 } 879 880 #if 0 881 /* 882 * Temporarily removed to avoid MAP_STACK panic, due to 883 * MAP_STACK being a huge hack. Will be added back in 884 * when MAP_STACK (and the user stack mapping) is fixed. 885 */ 886 /* 887 * It may be possible to simplify the entry 888 */ 889 vm_map_simplify_entry(map, new_entry); 890 #endif 891 892 if (cow & (MAP_PREFAULT|MAP_PREFAULT_PARTIAL)) { 893 mtx_lock(&Giant); 894 pmap_object_init_pt(map->pmap, start, 895 object, OFF_TO_IDX(offset), end - start, 896 cow & MAP_PREFAULT_PARTIAL); 897 mtx_unlock(&Giant); 898 } 899 900 return (KERN_SUCCESS); 901 } 902 903 /* 904 * Find sufficient space for `length' bytes in the given map, starting at 905 * `start'. The map must be locked. Returns 0 on success, 1 on no space. 906 */ 907 int 908 vm_map_findspace( 909 vm_map_t map, 910 vm_offset_t start, 911 vm_size_t length, 912 vm_offset_t *addr) 913 { 914 vm_map_entry_t entry, next; 915 vm_offset_t end; 916 917 if (start < map->min_offset) 918 start = map->min_offset; 919 if (start > map->max_offset) 920 return (1); 921 922 /* 923 * Look for the first possible address; if there's already something 924 * at this address, we have to start after it. 925 */ 926 if (start == map->min_offset) { 927 if ((entry = map->first_free) != &map->header) 928 start = entry->end; 929 } else { 930 vm_map_entry_t tmp; 931 932 if (vm_map_lookup_entry(map, start, &tmp)) 933 start = tmp->end; 934 entry = tmp; 935 } 936 937 /* 938 * Look through the rest of the map, trying to fit a new region in the 939 * gap between existing regions, or after the very last region. 940 */ 941 for (;; start = (entry = next)->end) { 942 /* 943 * Find the end of the proposed new region. Be sure we didn't 944 * go beyond the end of the map, or wrap around the address; 945 * if so, we lose. Otherwise, if this is the last entry, or 946 * if the proposed new region fits before the next entry, we 947 * win. 948 */ 949 end = start + length; 950 if (end > map->max_offset || end < start) 951 return (1); 952 next = entry->next; 953 if (next == &map->header || next->start >= end) 954 break; 955 } 956 *addr = start; 957 if (map == kernel_map) { 958 vm_offset_t ksize; 959 if ((ksize = round_page(start + length)) > kernel_vm_end) { 960 mtx_lock(&Giant); 961 pmap_growkernel(ksize); 962 mtx_unlock(&Giant); 963 } 964 } 965 return (0); 966 } 967 968 /* 969 * vm_map_find finds an unallocated region in the target address 970 * map with the given length. The search is defined to be 971 * first-fit from the specified address; the region found is 972 * returned in the same parameter. 973 * 974 * If object is non-NULL, ref count must be bumped by caller 975 * prior to making call to account for the new entry. 976 */ 977 int 978 vm_map_find(vm_map_t map, vm_object_t object, vm_ooffset_t offset, 979 vm_offset_t *addr, /* IN/OUT */ 980 vm_size_t length, boolean_t find_space, vm_prot_t prot, 981 vm_prot_t max, int cow) 982 { 983 vm_offset_t start; 984 int result, s = 0; 985 986 start = *addr; 987 988 if (map == kmem_map) 989 s = splvm(); 990 991 vm_map_lock(map); 992 if (find_space) { 993 if (vm_map_findspace(map, start, length, addr)) { 994 vm_map_unlock(map); 995 if (map == kmem_map) 996 splx(s); 997 return (KERN_NO_SPACE); 998 } 999 start = *addr; 1000 } 1001 result = vm_map_insert(map, object, offset, 1002 start, start + length, prot, max, cow); 1003 vm_map_unlock(map); 1004 1005 if (map == kmem_map) 1006 splx(s); 1007 1008 return (result); 1009 } 1010 1011 /* 1012 * vm_map_simplify_entry: 1013 * 1014 * Simplify the given map entry by merging with either neighbor. This 1015 * routine also has the ability to merge with both neighbors. 1016 * 1017 * The map must be locked. 1018 * 1019 * This routine guarentees that the passed entry remains valid (though 1020 * possibly extended). When merging, this routine may delete one or 1021 * both neighbors. 1022 */ 1023 void 1024 vm_map_simplify_entry(vm_map_t map, vm_map_entry_t entry) 1025 { 1026 vm_map_entry_t next, prev; 1027 vm_size_t prevsize, esize; 1028 1029 if (entry->eflags & (MAP_ENTRY_IN_TRANSITION | MAP_ENTRY_IS_SUB_MAP)) 1030 return; 1031 1032 prev = entry->prev; 1033 if (prev != &map->header) { 1034 prevsize = prev->end - prev->start; 1035 if ( (prev->end == entry->start) && 1036 (prev->object.vm_object == entry->object.vm_object) && 1037 (!prev->object.vm_object || 1038 (prev->offset + prevsize == entry->offset)) && 1039 (prev->eflags == entry->eflags) && 1040 (prev->protection == entry->protection) && 1041 (prev->max_protection == entry->max_protection) && 1042 (prev->inheritance == entry->inheritance) && 1043 (prev->wired_count == entry->wired_count)) { 1044 if (map->first_free == prev) 1045 map->first_free = entry; 1046 vm_map_entry_unlink(map, prev); 1047 entry->start = prev->start; 1048 entry->offset = prev->offset; 1049 if (prev->object.vm_object) 1050 vm_object_deallocate(prev->object.vm_object); 1051 vm_map_entry_dispose(map, prev); 1052 } 1053 } 1054 1055 next = entry->next; 1056 if (next != &map->header) { 1057 esize = entry->end - entry->start; 1058 if ((entry->end == next->start) && 1059 (next->object.vm_object == entry->object.vm_object) && 1060 (!entry->object.vm_object || 1061 (entry->offset + esize == next->offset)) && 1062 (next->eflags == entry->eflags) && 1063 (next->protection == entry->protection) && 1064 (next->max_protection == entry->max_protection) && 1065 (next->inheritance == entry->inheritance) && 1066 (next->wired_count == entry->wired_count)) { 1067 if (map->first_free == next) 1068 map->first_free = entry; 1069 vm_map_entry_unlink(map, next); 1070 entry->end = next->end; 1071 if (next->object.vm_object) 1072 vm_object_deallocate(next->object.vm_object); 1073 vm_map_entry_dispose(map, next); 1074 } 1075 } 1076 } 1077 /* 1078 * vm_map_clip_start: [ internal use only ] 1079 * 1080 * Asserts that the given entry begins at or after 1081 * the specified address; if necessary, 1082 * it splits the entry into two. 1083 */ 1084 #define vm_map_clip_start(map, entry, startaddr) \ 1085 { \ 1086 if (startaddr > entry->start) \ 1087 _vm_map_clip_start(map, entry, startaddr); \ 1088 } 1089 1090 /* 1091 * This routine is called only when it is known that 1092 * the entry must be split. 1093 */ 1094 static void 1095 _vm_map_clip_start(vm_map_t map, vm_map_entry_t entry, vm_offset_t start) 1096 { 1097 vm_map_entry_t new_entry; 1098 1099 /* 1100 * Split off the front portion -- note that we must insert the new 1101 * entry BEFORE this one, so that this entry has the specified 1102 * starting address. 1103 */ 1104 vm_map_simplify_entry(map, entry); 1105 1106 /* 1107 * If there is no object backing this entry, we might as well create 1108 * one now. If we defer it, an object can get created after the map 1109 * is clipped, and individual objects will be created for the split-up 1110 * map. This is a bit of a hack, but is also about the best place to 1111 * put this improvement. 1112 */ 1113 if (entry->object.vm_object == NULL && !map->system_map) { 1114 vm_object_t object; 1115 object = vm_object_allocate(OBJT_DEFAULT, 1116 atop(entry->end - entry->start)); 1117 entry->object.vm_object = object; 1118 entry->offset = 0; 1119 } 1120 1121 new_entry = vm_map_entry_create(map); 1122 *new_entry = *entry; 1123 1124 new_entry->end = start; 1125 entry->offset += (start - entry->start); 1126 entry->start = start; 1127 1128 vm_map_entry_link(map, entry->prev, new_entry); 1129 1130 if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0) { 1131 vm_object_reference(new_entry->object.vm_object); 1132 } 1133 } 1134 1135 /* 1136 * vm_map_clip_end: [ internal use only ] 1137 * 1138 * Asserts that the given entry ends at or before 1139 * the specified address; if necessary, 1140 * it splits the entry into two. 1141 */ 1142 #define vm_map_clip_end(map, entry, endaddr) \ 1143 { \ 1144 if ((endaddr) < (entry->end)) \ 1145 _vm_map_clip_end((map), (entry), (endaddr)); \ 1146 } 1147 1148 /* 1149 * This routine is called only when it is known that 1150 * the entry must be split. 1151 */ 1152 static void 1153 _vm_map_clip_end(vm_map_t map, vm_map_entry_t entry, vm_offset_t end) 1154 { 1155 vm_map_entry_t new_entry; 1156 1157 /* 1158 * If there is no object backing this entry, we might as well create 1159 * one now. If we defer it, an object can get created after the map 1160 * is clipped, and individual objects will be created for the split-up 1161 * map. This is a bit of a hack, but is also about the best place to 1162 * put this improvement. 1163 */ 1164 if (entry->object.vm_object == NULL && !map->system_map) { 1165 vm_object_t object; 1166 object = vm_object_allocate(OBJT_DEFAULT, 1167 atop(entry->end - entry->start)); 1168 entry->object.vm_object = object; 1169 entry->offset = 0; 1170 } 1171 1172 /* 1173 * Create a new entry and insert it AFTER the specified entry 1174 */ 1175 new_entry = vm_map_entry_create(map); 1176 *new_entry = *entry; 1177 1178 new_entry->start = entry->end = end; 1179 new_entry->offset += (end - entry->start); 1180 1181 vm_map_entry_link(map, entry, new_entry); 1182 1183 if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0) { 1184 vm_object_reference(new_entry->object.vm_object); 1185 } 1186 } 1187 1188 /* 1189 * VM_MAP_RANGE_CHECK: [ internal use only ] 1190 * 1191 * Asserts that the starting and ending region 1192 * addresses fall within the valid range of the map. 1193 */ 1194 #define VM_MAP_RANGE_CHECK(map, start, end) \ 1195 { \ 1196 if (start < vm_map_min(map)) \ 1197 start = vm_map_min(map); \ 1198 if (end > vm_map_max(map)) \ 1199 end = vm_map_max(map); \ 1200 if (start > end) \ 1201 start = end; \ 1202 } 1203 1204 /* 1205 * vm_map_submap: [ kernel use only ] 1206 * 1207 * Mark the given range as handled by a subordinate map. 1208 * 1209 * This range must have been created with vm_map_find, 1210 * and no other operations may have been performed on this 1211 * range prior to calling vm_map_submap. 1212 * 1213 * Only a limited number of operations can be performed 1214 * within this rage after calling vm_map_submap: 1215 * vm_fault 1216 * [Don't try vm_map_copy!] 1217 * 1218 * To remove a submapping, one must first remove the 1219 * range from the superior map, and then destroy the 1220 * submap (if desired). [Better yet, don't try it.] 1221 */ 1222 int 1223 vm_map_submap( 1224 vm_map_t map, 1225 vm_offset_t start, 1226 vm_offset_t end, 1227 vm_map_t submap) 1228 { 1229 vm_map_entry_t entry; 1230 int result = KERN_INVALID_ARGUMENT; 1231 1232 vm_map_lock(map); 1233 1234 VM_MAP_RANGE_CHECK(map, start, end); 1235 1236 if (vm_map_lookup_entry(map, start, &entry)) { 1237 vm_map_clip_start(map, entry, start); 1238 } else 1239 entry = entry->next; 1240 1241 vm_map_clip_end(map, entry, end); 1242 1243 if ((entry->start == start) && (entry->end == end) && 1244 ((entry->eflags & MAP_ENTRY_COW) == 0) && 1245 (entry->object.vm_object == NULL)) { 1246 entry->object.sub_map = submap; 1247 entry->eflags |= MAP_ENTRY_IS_SUB_MAP; 1248 result = KERN_SUCCESS; 1249 } 1250 vm_map_unlock(map); 1251 1252 return (result); 1253 } 1254 1255 /* 1256 * vm_map_protect: 1257 * 1258 * Sets the protection of the specified address 1259 * region in the target map. If "set_max" is 1260 * specified, the maximum protection is to be set; 1261 * otherwise, only the current protection is affected. 1262 */ 1263 int 1264 vm_map_protect(vm_map_t map, vm_offset_t start, vm_offset_t end, 1265 vm_prot_t new_prot, boolean_t set_max) 1266 { 1267 vm_map_entry_t current; 1268 vm_map_entry_t entry; 1269 1270 vm_map_lock(map); 1271 1272 VM_MAP_RANGE_CHECK(map, start, end); 1273 1274 if (vm_map_lookup_entry(map, start, &entry)) { 1275 vm_map_clip_start(map, entry, start); 1276 } else { 1277 entry = entry->next; 1278 } 1279 1280 /* 1281 * Make a first pass to check for protection violations. 1282 */ 1283 current = entry; 1284 while ((current != &map->header) && (current->start < end)) { 1285 if (current->eflags & MAP_ENTRY_IS_SUB_MAP) { 1286 vm_map_unlock(map); 1287 return (KERN_INVALID_ARGUMENT); 1288 } 1289 if ((new_prot & current->max_protection) != new_prot) { 1290 vm_map_unlock(map); 1291 return (KERN_PROTECTION_FAILURE); 1292 } 1293 current = current->next; 1294 } 1295 1296 /* 1297 * Go back and fix up protections. [Note that clipping is not 1298 * necessary the second time.] 1299 */ 1300 current = entry; 1301 while ((current != &map->header) && (current->start < end)) { 1302 vm_prot_t old_prot; 1303 1304 vm_map_clip_end(map, current, end); 1305 1306 old_prot = current->protection; 1307 if (set_max) 1308 current->protection = 1309 (current->max_protection = new_prot) & 1310 old_prot; 1311 else 1312 current->protection = new_prot; 1313 1314 /* 1315 * Update physical map if necessary. Worry about copy-on-write 1316 * here -- CHECK THIS XXX 1317 */ 1318 if (current->protection != old_prot) { 1319 mtx_lock(&Giant); 1320 vm_page_lock_queues(); 1321 #define MASK(entry) (((entry)->eflags & MAP_ENTRY_COW) ? ~VM_PROT_WRITE : \ 1322 VM_PROT_ALL) 1323 pmap_protect(map->pmap, current->start, 1324 current->end, 1325 current->protection & MASK(current)); 1326 #undef MASK 1327 vm_page_unlock_queues(); 1328 mtx_unlock(&Giant); 1329 } 1330 vm_map_simplify_entry(map, current); 1331 current = current->next; 1332 } 1333 vm_map_unlock(map); 1334 return (KERN_SUCCESS); 1335 } 1336 1337 /* 1338 * vm_map_madvise: 1339 * 1340 * This routine traverses a processes map handling the madvise 1341 * system call. Advisories are classified as either those effecting 1342 * the vm_map_entry structure, or those effecting the underlying 1343 * objects. 1344 */ 1345 int 1346 vm_map_madvise( 1347 vm_map_t map, 1348 vm_offset_t start, 1349 vm_offset_t end, 1350 int behav) 1351 { 1352 vm_map_entry_t current, entry; 1353 int modify_map = 0; 1354 1355 /* 1356 * Some madvise calls directly modify the vm_map_entry, in which case 1357 * we need to use an exclusive lock on the map and we need to perform 1358 * various clipping operations. Otherwise we only need a read-lock 1359 * on the map. 1360 */ 1361 switch(behav) { 1362 case MADV_NORMAL: 1363 case MADV_SEQUENTIAL: 1364 case MADV_RANDOM: 1365 case MADV_NOSYNC: 1366 case MADV_AUTOSYNC: 1367 case MADV_NOCORE: 1368 case MADV_CORE: 1369 modify_map = 1; 1370 vm_map_lock(map); 1371 break; 1372 case MADV_WILLNEED: 1373 case MADV_DONTNEED: 1374 case MADV_FREE: 1375 vm_map_lock_read(map); 1376 break; 1377 default: 1378 return (KERN_INVALID_ARGUMENT); 1379 } 1380 1381 /* 1382 * Locate starting entry and clip if necessary. 1383 */ 1384 VM_MAP_RANGE_CHECK(map, start, end); 1385 1386 if (vm_map_lookup_entry(map, start, &entry)) { 1387 if (modify_map) 1388 vm_map_clip_start(map, entry, start); 1389 } else { 1390 entry = entry->next; 1391 } 1392 1393 if (modify_map) { 1394 /* 1395 * madvise behaviors that are implemented in the vm_map_entry. 1396 * 1397 * We clip the vm_map_entry so that behavioral changes are 1398 * limited to the specified address range. 1399 */ 1400 for (current = entry; 1401 (current != &map->header) && (current->start < end); 1402 current = current->next 1403 ) { 1404 if (current->eflags & MAP_ENTRY_IS_SUB_MAP) 1405 continue; 1406 1407 vm_map_clip_end(map, current, end); 1408 1409 switch (behav) { 1410 case MADV_NORMAL: 1411 vm_map_entry_set_behavior(current, MAP_ENTRY_BEHAV_NORMAL); 1412 break; 1413 case MADV_SEQUENTIAL: 1414 vm_map_entry_set_behavior(current, MAP_ENTRY_BEHAV_SEQUENTIAL); 1415 break; 1416 case MADV_RANDOM: 1417 vm_map_entry_set_behavior(current, MAP_ENTRY_BEHAV_RANDOM); 1418 break; 1419 case MADV_NOSYNC: 1420 current->eflags |= MAP_ENTRY_NOSYNC; 1421 break; 1422 case MADV_AUTOSYNC: 1423 current->eflags &= ~MAP_ENTRY_NOSYNC; 1424 break; 1425 case MADV_NOCORE: 1426 current->eflags |= MAP_ENTRY_NOCOREDUMP; 1427 break; 1428 case MADV_CORE: 1429 current->eflags &= ~MAP_ENTRY_NOCOREDUMP; 1430 break; 1431 default: 1432 break; 1433 } 1434 vm_map_simplify_entry(map, current); 1435 } 1436 vm_map_unlock(map); 1437 } else { 1438 vm_pindex_t pindex; 1439 int count; 1440 1441 /* 1442 * madvise behaviors that are implemented in the underlying 1443 * vm_object. 1444 * 1445 * Since we don't clip the vm_map_entry, we have to clip 1446 * the vm_object pindex and count. 1447 */ 1448 for (current = entry; 1449 (current != &map->header) && (current->start < end); 1450 current = current->next 1451 ) { 1452 vm_offset_t useStart; 1453 1454 if (current->eflags & MAP_ENTRY_IS_SUB_MAP) 1455 continue; 1456 1457 pindex = OFF_TO_IDX(current->offset); 1458 count = atop(current->end - current->start); 1459 useStart = current->start; 1460 1461 if (current->start < start) { 1462 pindex += atop(start - current->start); 1463 count -= atop(start - current->start); 1464 useStart = start; 1465 } 1466 if (current->end > end) 1467 count -= atop(current->end - end); 1468 1469 if (count <= 0) 1470 continue; 1471 1472 vm_object_madvise(current->object.vm_object, 1473 pindex, count, behav); 1474 if (behav == MADV_WILLNEED) { 1475 mtx_lock(&Giant); 1476 pmap_object_init_pt( 1477 map->pmap, 1478 useStart, 1479 current->object.vm_object, 1480 pindex, 1481 (count << PAGE_SHIFT), 1482 MAP_PREFAULT_MADVISE 1483 ); 1484 mtx_unlock(&Giant); 1485 } 1486 } 1487 vm_map_unlock_read(map); 1488 } 1489 return (0); 1490 } 1491 1492 1493 /* 1494 * vm_map_inherit: 1495 * 1496 * Sets the inheritance of the specified address 1497 * range in the target map. Inheritance 1498 * affects how the map will be shared with 1499 * child maps at the time of vm_map_fork. 1500 */ 1501 int 1502 vm_map_inherit(vm_map_t map, vm_offset_t start, vm_offset_t end, 1503 vm_inherit_t new_inheritance) 1504 { 1505 vm_map_entry_t entry; 1506 vm_map_entry_t temp_entry; 1507 1508 switch (new_inheritance) { 1509 case VM_INHERIT_NONE: 1510 case VM_INHERIT_COPY: 1511 case VM_INHERIT_SHARE: 1512 break; 1513 default: 1514 return (KERN_INVALID_ARGUMENT); 1515 } 1516 vm_map_lock(map); 1517 VM_MAP_RANGE_CHECK(map, start, end); 1518 if (vm_map_lookup_entry(map, start, &temp_entry)) { 1519 entry = temp_entry; 1520 vm_map_clip_start(map, entry, start); 1521 } else 1522 entry = temp_entry->next; 1523 while ((entry != &map->header) && (entry->start < end)) { 1524 vm_map_clip_end(map, entry, end); 1525 entry->inheritance = new_inheritance; 1526 vm_map_simplify_entry(map, entry); 1527 entry = entry->next; 1528 } 1529 vm_map_unlock(map); 1530 return (KERN_SUCCESS); 1531 } 1532 1533 /* 1534 * vm_map_unwire: 1535 * 1536 * Implements both kernel and user unwiring. 1537 */ 1538 int 1539 vm_map_unwire(vm_map_t map, vm_offset_t start, vm_offset_t end, 1540 boolean_t user_unwire) 1541 { 1542 vm_map_entry_t entry, first_entry, tmp_entry; 1543 vm_offset_t saved_start; 1544 unsigned int last_timestamp; 1545 int rv; 1546 boolean_t need_wakeup, result; 1547 1548 vm_map_lock(map); 1549 VM_MAP_RANGE_CHECK(map, start, end); 1550 if (!vm_map_lookup_entry(map, start, &first_entry)) { 1551 vm_map_unlock(map); 1552 return (KERN_INVALID_ADDRESS); 1553 } 1554 last_timestamp = map->timestamp; 1555 entry = first_entry; 1556 while (entry != &map->header && entry->start < end) { 1557 if (entry->eflags & MAP_ENTRY_IN_TRANSITION) { 1558 /* 1559 * We have not yet clipped the entry. 1560 */ 1561 saved_start = (start >= entry->start) ? start : 1562 entry->start; 1563 entry->eflags |= MAP_ENTRY_NEEDS_WAKEUP; 1564 if (vm_map_unlock_and_wait(map, user_unwire)) { 1565 /* 1566 * Allow interruption of user unwiring? 1567 */ 1568 } 1569 vm_map_lock(map); 1570 if (last_timestamp+1 != map->timestamp) { 1571 /* 1572 * Look again for the entry because the map was 1573 * modified while it was unlocked. 1574 * Specifically, the entry may have been 1575 * clipped, merged, or deleted. 1576 */ 1577 if (!vm_map_lookup_entry(map, saved_start, 1578 &tmp_entry)) { 1579 if (saved_start == start) { 1580 /* 1581 * First_entry has been deleted. 1582 */ 1583 vm_map_unlock(map); 1584 return (KERN_INVALID_ADDRESS); 1585 } 1586 end = saved_start; 1587 rv = KERN_INVALID_ADDRESS; 1588 goto done; 1589 } 1590 if (entry == first_entry) 1591 first_entry = tmp_entry; 1592 else 1593 first_entry = NULL; 1594 entry = tmp_entry; 1595 } 1596 last_timestamp = map->timestamp; 1597 continue; 1598 } 1599 vm_map_clip_start(map, entry, start); 1600 vm_map_clip_end(map, entry, end); 1601 /* 1602 * Mark the entry in case the map lock is released. (See 1603 * above.) 1604 */ 1605 entry->eflags |= MAP_ENTRY_IN_TRANSITION; 1606 /* 1607 * Check the map for holes in the specified region. 1608 */ 1609 if (entry->end < end && (entry->next == &map->header || 1610 entry->next->start > entry->end)) { 1611 end = entry->end; 1612 rv = KERN_INVALID_ADDRESS; 1613 goto done; 1614 } 1615 /* 1616 * Require that the entry is wired. 1617 */ 1618 if (entry->wired_count == 0 || (user_unwire && 1619 (entry->eflags & MAP_ENTRY_USER_WIRED) == 0)) { 1620 end = entry->end; 1621 rv = KERN_INVALID_ARGUMENT; 1622 goto done; 1623 } 1624 entry = entry->next; 1625 } 1626 rv = KERN_SUCCESS; 1627 done: 1628 need_wakeup = FALSE; 1629 if (first_entry == NULL) { 1630 result = vm_map_lookup_entry(map, start, &first_entry); 1631 KASSERT(result, ("vm_map_unwire: lookup failed")); 1632 } 1633 entry = first_entry; 1634 while (entry != &map->header && entry->start < end) { 1635 if (rv == KERN_SUCCESS) { 1636 if (user_unwire) 1637 entry->eflags &= ~MAP_ENTRY_USER_WIRED; 1638 entry->wired_count--; 1639 if (entry->wired_count == 0) { 1640 /* 1641 * Retain the map lock. 1642 */ 1643 vm_fault_unwire(map, entry->start, entry->end); 1644 } 1645 } 1646 KASSERT(entry->eflags & MAP_ENTRY_IN_TRANSITION, 1647 ("vm_map_unwire: in-transition flag missing")); 1648 entry->eflags &= ~MAP_ENTRY_IN_TRANSITION; 1649 if (entry->eflags & MAP_ENTRY_NEEDS_WAKEUP) { 1650 entry->eflags &= ~MAP_ENTRY_NEEDS_WAKEUP; 1651 need_wakeup = TRUE; 1652 } 1653 vm_map_simplify_entry(map, entry); 1654 entry = entry->next; 1655 } 1656 vm_map_unlock(map); 1657 if (need_wakeup) 1658 vm_map_wakeup(map); 1659 return (rv); 1660 } 1661 1662 /* 1663 * vm_map_wire: 1664 * 1665 * Implements both kernel and user wiring. 1666 */ 1667 int 1668 vm_map_wire(vm_map_t map, vm_offset_t start, vm_offset_t end, 1669 boolean_t user_wire) 1670 { 1671 vm_map_entry_t entry, first_entry, tmp_entry; 1672 vm_offset_t saved_end, saved_start; 1673 unsigned int last_timestamp; 1674 int rv; 1675 boolean_t need_wakeup, result; 1676 1677 vm_map_lock(map); 1678 VM_MAP_RANGE_CHECK(map, start, end); 1679 if (!vm_map_lookup_entry(map, start, &first_entry)) { 1680 vm_map_unlock(map); 1681 return (KERN_INVALID_ADDRESS); 1682 } 1683 last_timestamp = map->timestamp; 1684 entry = first_entry; 1685 while (entry != &map->header && entry->start < end) { 1686 if (entry->eflags & MAP_ENTRY_IN_TRANSITION) { 1687 /* 1688 * We have not yet clipped the entry. 1689 */ 1690 saved_start = (start >= entry->start) ? start : 1691 entry->start; 1692 entry->eflags |= MAP_ENTRY_NEEDS_WAKEUP; 1693 if (vm_map_unlock_and_wait(map, user_wire)) { 1694 /* 1695 * Allow interruption of user wiring? 1696 */ 1697 } 1698 vm_map_lock(map); 1699 if (last_timestamp + 1 != map->timestamp) { 1700 /* 1701 * Look again for the entry because the map was 1702 * modified while it was unlocked. 1703 * Specifically, the entry may have been 1704 * clipped, merged, or deleted. 1705 */ 1706 if (!vm_map_lookup_entry(map, saved_start, 1707 &tmp_entry)) { 1708 if (saved_start == start) { 1709 /* 1710 * first_entry has been deleted. 1711 */ 1712 vm_map_unlock(map); 1713 return (KERN_INVALID_ADDRESS); 1714 } 1715 end = saved_start; 1716 rv = KERN_INVALID_ADDRESS; 1717 goto done; 1718 } 1719 if (entry == first_entry) 1720 first_entry = tmp_entry; 1721 else 1722 first_entry = NULL; 1723 entry = tmp_entry; 1724 } 1725 last_timestamp = map->timestamp; 1726 continue; 1727 } 1728 vm_map_clip_start(map, entry, start); 1729 vm_map_clip_end(map, entry, end); 1730 /* 1731 * Mark the entry in case the map lock is released. (See 1732 * above.) 1733 */ 1734 entry->eflags |= MAP_ENTRY_IN_TRANSITION; 1735 /* 1736 * 1737 */ 1738 if (entry->wired_count == 0) { 1739 entry->wired_count++; 1740 saved_start = entry->start; 1741 saved_end = entry->end; 1742 /* 1743 * Release the map lock, relying on the in-transition 1744 * mark. 1745 */ 1746 vm_map_unlock(map); 1747 rv = vm_fault_wire(map, saved_start, saved_end, 1748 user_wire); 1749 vm_map_lock(map); 1750 if (last_timestamp + 1 != map->timestamp) { 1751 /* 1752 * Look again for the entry because the map was 1753 * modified while it was unlocked. The entry 1754 * may have been clipped, but NOT merged or 1755 * deleted. 1756 */ 1757 result = vm_map_lookup_entry(map, saved_start, 1758 &tmp_entry); 1759 KASSERT(result, ("vm_map_wire: lookup failed")); 1760 if (entry == first_entry) 1761 first_entry = tmp_entry; 1762 else 1763 first_entry = NULL; 1764 entry = tmp_entry; 1765 while (entry->end < saved_end) { 1766 if (rv != KERN_SUCCESS) { 1767 KASSERT(entry->wired_count == 1, 1768 ("vm_map_wire: bad count")); 1769 entry->wired_count = -1; 1770 } 1771 entry = entry->next; 1772 } 1773 } 1774 last_timestamp = map->timestamp; 1775 if (rv != KERN_SUCCESS) { 1776 KASSERT(entry->wired_count == 1, 1777 ("vm_map_wire: bad count")); 1778 /* 1779 * Assign an out-of-range value to represent 1780 * the failure to wire this entry. 1781 */ 1782 entry->wired_count = -1; 1783 end = entry->end; 1784 goto done; 1785 } 1786 } else if (!user_wire || 1787 (entry->eflags & MAP_ENTRY_USER_WIRED) == 0) { 1788 entry->wired_count++; 1789 } 1790 /* 1791 * Check the map for holes in the specified region. 1792 */ 1793 if (entry->end < end && (entry->next == &map->header || 1794 entry->next->start > entry->end)) { 1795 end = entry->end; 1796 rv = KERN_INVALID_ADDRESS; 1797 goto done; 1798 } 1799 entry = entry->next; 1800 } 1801 rv = KERN_SUCCESS; 1802 done: 1803 need_wakeup = FALSE; 1804 if (first_entry == NULL) { 1805 result = vm_map_lookup_entry(map, start, &first_entry); 1806 KASSERT(result, ("vm_map_wire: lookup failed")); 1807 } 1808 entry = first_entry; 1809 while (entry != &map->header && entry->start < end) { 1810 if (rv == KERN_SUCCESS) { 1811 if (user_wire) 1812 entry->eflags |= MAP_ENTRY_USER_WIRED; 1813 } else if (entry->wired_count == -1) { 1814 /* 1815 * Wiring failed on this entry. Thus, unwiring is 1816 * unnecessary. 1817 */ 1818 entry->wired_count = 0; 1819 } else { 1820 if (!user_wire || 1821 (entry->eflags & MAP_ENTRY_USER_WIRED) == 0) 1822 entry->wired_count--; 1823 if (entry->wired_count == 0) { 1824 /* 1825 * Retain the map lock. 1826 */ 1827 vm_fault_unwire(map, entry->start, entry->end); 1828 } 1829 } 1830 KASSERT(entry->eflags & MAP_ENTRY_IN_TRANSITION, 1831 ("vm_map_wire: in-transition flag missing")); 1832 entry->eflags &= ~MAP_ENTRY_IN_TRANSITION; 1833 if (entry->eflags & MAP_ENTRY_NEEDS_WAKEUP) { 1834 entry->eflags &= ~MAP_ENTRY_NEEDS_WAKEUP; 1835 need_wakeup = TRUE; 1836 } 1837 vm_map_simplify_entry(map, entry); 1838 entry = entry->next; 1839 } 1840 vm_map_unlock(map); 1841 if (need_wakeup) 1842 vm_map_wakeup(map); 1843 return (rv); 1844 } 1845 1846 /* 1847 * vm_map_clean 1848 * 1849 * Push any dirty cached pages in the address range to their pager. 1850 * If syncio is TRUE, dirty pages are written synchronously. 1851 * If invalidate is TRUE, any cached pages are freed as well. 1852 * 1853 * Returns an error if any part of the specified range is not mapped. 1854 */ 1855 int 1856 vm_map_clean( 1857 vm_map_t map, 1858 vm_offset_t start, 1859 vm_offset_t end, 1860 boolean_t syncio, 1861 boolean_t invalidate) 1862 { 1863 vm_map_entry_t current; 1864 vm_map_entry_t entry; 1865 vm_size_t size; 1866 vm_object_t object; 1867 vm_ooffset_t offset; 1868 1869 GIANT_REQUIRED; 1870 1871 vm_map_lock_read(map); 1872 VM_MAP_RANGE_CHECK(map, start, end); 1873 if (!vm_map_lookup_entry(map, start, &entry)) { 1874 vm_map_unlock_read(map); 1875 return (KERN_INVALID_ADDRESS); 1876 } 1877 /* 1878 * Make a first pass to check for holes. 1879 */ 1880 for (current = entry; current->start < end; current = current->next) { 1881 if (current->eflags & MAP_ENTRY_IS_SUB_MAP) { 1882 vm_map_unlock_read(map); 1883 return (KERN_INVALID_ARGUMENT); 1884 } 1885 if (end > current->end && 1886 (current->next == &map->header || 1887 current->end != current->next->start)) { 1888 vm_map_unlock_read(map); 1889 return (KERN_INVALID_ADDRESS); 1890 } 1891 } 1892 1893 if (invalidate) { 1894 vm_page_lock_queues(); 1895 pmap_remove(map->pmap, start, end); 1896 vm_page_unlock_queues(); 1897 } 1898 /* 1899 * Make a second pass, cleaning/uncaching pages from the indicated 1900 * objects as we go. 1901 */ 1902 for (current = entry; current->start < end; current = current->next) { 1903 offset = current->offset + (start - current->start); 1904 size = (end <= current->end ? end : current->end) - start; 1905 if (current->eflags & MAP_ENTRY_IS_SUB_MAP) { 1906 vm_map_t smap; 1907 vm_map_entry_t tentry; 1908 vm_size_t tsize; 1909 1910 smap = current->object.sub_map; 1911 vm_map_lock_read(smap); 1912 (void) vm_map_lookup_entry(smap, offset, &tentry); 1913 tsize = tentry->end - offset; 1914 if (tsize < size) 1915 size = tsize; 1916 object = tentry->object.vm_object; 1917 offset = tentry->offset + (offset - tentry->start); 1918 vm_map_unlock_read(smap); 1919 } else { 1920 object = current->object.vm_object; 1921 } 1922 /* 1923 * Note that there is absolutely no sense in writing out 1924 * anonymous objects, so we track down the vnode object 1925 * to write out. 1926 * We invalidate (remove) all pages from the address space 1927 * anyway, for semantic correctness. 1928 * 1929 * note: certain anonymous maps, such as MAP_NOSYNC maps, 1930 * may start out with a NULL object. 1931 */ 1932 while (object && object->backing_object) { 1933 object = object->backing_object; 1934 offset += object->backing_object_offset; 1935 if (object->size < OFF_TO_IDX(offset + size)) 1936 size = IDX_TO_OFF(object->size) - offset; 1937 } 1938 if (object && (object->type == OBJT_VNODE) && 1939 (current->protection & VM_PROT_WRITE)) { 1940 /* 1941 * Flush pages if writing is allowed, invalidate them 1942 * if invalidation requested. Pages undergoing I/O 1943 * will be ignored by vm_object_page_remove(). 1944 * 1945 * We cannot lock the vnode and then wait for paging 1946 * to complete without deadlocking against vm_fault. 1947 * Instead we simply call vm_object_page_remove() and 1948 * allow it to block internally on a page-by-page 1949 * basis when it encounters pages undergoing async 1950 * I/O. 1951 */ 1952 int flags; 1953 1954 vm_object_reference(object); 1955 vn_lock(object->handle, LK_EXCLUSIVE | LK_RETRY, curthread); 1956 flags = (syncio || invalidate) ? OBJPC_SYNC : 0; 1957 flags |= invalidate ? OBJPC_INVAL : 0; 1958 vm_object_page_clean(object, 1959 OFF_TO_IDX(offset), 1960 OFF_TO_IDX(offset + size + PAGE_MASK), 1961 flags); 1962 VOP_UNLOCK(object->handle, 0, curthread); 1963 vm_object_deallocate(object); 1964 } 1965 if (object && invalidate && 1966 ((object->type == OBJT_VNODE) || 1967 (object->type == OBJT_DEVICE))) { 1968 vm_object_reference(object); 1969 vm_object_lock(object); 1970 vm_object_page_remove(object, 1971 OFF_TO_IDX(offset), 1972 OFF_TO_IDX(offset + size + PAGE_MASK), 1973 FALSE); 1974 vm_object_unlock(object); 1975 vm_object_deallocate(object); 1976 } 1977 start += size; 1978 } 1979 1980 vm_map_unlock_read(map); 1981 return (KERN_SUCCESS); 1982 } 1983 1984 /* 1985 * vm_map_entry_unwire: [ internal use only ] 1986 * 1987 * Make the region specified by this entry pageable. 1988 * 1989 * The map in question should be locked. 1990 * [This is the reason for this routine's existence.] 1991 */ 1992 static void 1993 vm_map_entry_unwire(vm_map_t map, vm_map_entry_t entry) 1994 { 1995 vm_fault_unwire(map, entry->start, entry->end); 1996 entry->wired_count = 0; 1997 } 1998 1999 /* 2000 * vm_map_entry_delete: [ internal use only ] 2001 * 2002 * Deallocate the given entry from the target map. 2003 */ 2004 static void 2005 vm_map_entry_delete(vm_map_t map, vm_map_entry_t entry) 2006 { 2007 vm_map_entry_unlink(map, entry); 2008 map->size -= entry->end - entry->start; 2009 2010 if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0) { 2011 vm_object_deallocate(entry->object.vm_object); 2012 } 2013 2014 vm_map_entry_dispose(map, entry); 2015 } 2016 2017 /* 2018 * vm_map_delete: [ internal use only ] 2019 * 2020 * Deallocates the given address range from the target 2021 * map. 2022 */ 2023 int 2024 vm_map_delete(vm_map_t map, vm_offset_t start, vm_offset_t end) 2025 { 2026 vm_object_t object; 2027 vm_map_entry_t entry; 2028 vm_map_entry_t first_entry; 2029 2030 /* 2031 * Find the start of the region, and clip it 2032 */ 2033 if (!vm_map_lookup_entry(map, start, &first_entry)) 2034 entry = first_entry->next; 2035 else { 2036 entry = first_entry; 2037 vm_map_clip_start(map, entry, start); 2038 } 2039 2040 /* 2041 * Save the free space hint 2042 */ 2043 if (entry == &map->header) { 2044 map->first_free = &map->header; 2045 } else if (map->first_free->start >= start) { 2046 map->first_free = entry->prev; 2047 } 2048 2049 /* 2050 * Step through all entries in this region 2051 */ 2052 while ((entry != &map->header) && (entry->start < end)) { 2053 vm_map_entry_t next; 2054 vm_offset_t s, e; 2055 vm_pindex_t offidxstart, offidxend, count; 2056 2057 /* 2058 * Wait for wiring or unwiring of an entry to complete. 2059 */ 2060 if ((entry->eflags & MAP_ENTRY_IN_TRANSITION) != 0) { 2061 unsigned int last_timestamp; 2062 vm_offset_t saved_start; 2063 vm_map_entry_t tmp_entry; 2064 2065 saved_start = entry->start; 2066 entry->eflags |= MAP_ENTRY_NEEDS_WAKEUP; 2067 last_timestamp = map->timestamp; 2068 (void) vm_map_unlock_and_wait(map, FALSE); 2069 vm_map_lock(map); 2070 if (last_timestamp + 1 != map->timestamp) { 2071 /* 2072 * Look again for the entry because the map was 2073 * modified while it was unlocked. 2074 * Specifically, the entry may have been 2075 * clipped, merged, or deleted. 2076 */ 2077 if (!vm_map_lookup_entry(map, saved_start, 2078 &tmp_entry)) 2079 entry = tmp_entry->next; 2080 else { 2081 entry = tmp_entry; 2082 vm_map_clip_start(map, entry, 2083 saved_start); 2084 } 2085 } 2086 continue; 2087 } 2088 vm_map_clip_end(map, entry, end); 2089 2090 s = entry->start; 2091 e = entry->end; 2092 next = entry->next; 2093 2094 offidxstart = OFF_TO_IDX(entry->offset); 2095 count = OFF_TO_IDX(e - s); 2096 object = entry->object.vm_object; 2097 2098 /* 2099 * Unwire before removing addresses from the pmap; otherwise, 2100 * unwiring will put the entries back in the pmap. 2101 */ 2102 if (entry->wired_count != 0) { 2103 vm_map_entry_unwire(map, entry); 2104 } 2105 2106 offidxend = offidxstart + count; 2107 2108 if ((object == kernel_object) || (object == kmem_object)) { 2109 vm_object_lock(object); 2110 vm_object_page_remove(object, offidxstart, offidxend, FALSE); 2111 vm_object_unlock(object); 2112 } else { 2113 vm_object_lock(object); 2114 vm_page_lock_queues(); 2115 pmap_remove(map->pmap, s, e); 2116 vm_page_unlock_queues(); 2117 if (object != NULL && 2118 object->ref_count != 1 && 2119 (object->flags & (OBJ_NOSPLIT|OBJ_ONEMAPPING)) == OBJ_ONEMAPPING && 2120 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) { 2121 vm_object_collapse(object); 2122 vm_object_page_remove(object, offidxstart, offidxend, FALSE); 2123 if (object->type == OBJT_SWAP) { 2124 swap_pager_freespace(object, offidxstart, count); 2125 } 2126 if (offidxend >= object->size && 2127 offidxstart < object->size) { 2128 object->size = offidxstart; 2129 } 2130 } 2131 vm_object_unlock(object); 2132 } 2133 2134 /* 2135 * Delete the entry (which may delete the object) only after 2136 * removing all pmap entries pointing to its pages. 2137 * (Otherwise, its page frames may be reallocated, and any 2138 * modify bits will be set in the wrong object!) 2139 */ 2140 vm_map_entry_delete(map, entry); 2141 entry = next; 2142 } 2143 return (KERN_SUCCESS); 2144 } 2145 2146 /* 2147 * vm_map_remove: 2148 * 2149 * Remove the given address range from the target map. 2150 * This is the exported form of vm_map_delete. 2151 */ 2152 int 2153 vm_map_remove(vm_map_t map, vm_offset_t start, vm_offset_t end) 2154 { 2155 int result, s = 0; 2156 2157 if (map == kmem_map) 2158 s = splvm(); 2159 2160 vm_map_lock(map); 2161 VM_MAP_RANGE_CHECK(map, start, end); 2162 result = vm_map_delete(map, start, end); 2163 vm_map_unlock(map); 2164 2165 if (map == kmem_map) 2166 splx(s); 2167 2168 return (result); 2169 } 2170 2171 /* 2172 * vm_map_check_protection: 2173 * 2174 * Assert that the target map allows the specified 2175 * privilege on the entire address region given. 2176 * The entire region must be allocated. 2177 */ 2178 boolean_t 2179 vm_map_check_protection(vm_map_t map, vm_offset_t start, vm_offset_t end, 2180 vm_prot_t protection) 2181 { 2182 vm_map_entry_t entry; 2183 vm_map_entry_t tmp_entry; 2184 2185 vm_map_lock_read(map); 2186 if (!vm_map_lookup_entry(map, start, &tmp_entry)) { 2187 vm_map_unlock_read(map); 2188 return (FALSE); 2189 } 2190 entry = tmp_entry; 2191 2192 while (start < end) { 2193 if (entry == &map->header) { 2194 vm_map_unlock_read(map); 2195 return (FALSE); 2196 } 2197 /* 2198 * No holes allowed! 2199 */ 2200 if (start < entry->start) { 2201 vm_map_unlock_read(map); 2202 return (FALSE); 2203 } 2204 /* 2205 * Check protection associated with entry. 2206 */ 2207 if ((entry->protection & protection) != protection) { 2208 vm_map_unlock_read(map); 2209 return (FALSE); 2210 } 2211 /* go to next entry */ 2212 start = entry->end; 2213 entry = entry->next; 2214 } 2215 vm_map_unlock_read(map); 2216 return (TRUE); 2217 } 2218 2219 /* 2220 * vm_map_copy_entry: 2221 * 2222 * Copies the contents of the source entry to the destination 2223 * entry. The entries *must* be aligned properly. 2224 */ 2225 static void 2226 vm_map_copy_entry( 2227 vm_map_t src_map, 2228 vm_map_t dst_map, 2229 vm_map_entry_t src_entry, 2230 vm_map_entry_t dst_entry) 2231 { 2232 vm_object_t src_object; 2233 2234 if ((dst_entry->eflags|src_entry->eflags) & MAP_ENTRY_IS_SUB_MAP) 2235 return; 2236 2237 if (src_entry->wired_count == 0) { 2238 2239 /* 2240 * If the source entry is marked needs_copy, it is already 2241 * write-protected. 2242 */ 2243 if ((src_entry->eflags & MAP_ENTRY_NEEDS_COPY) == 0) { 2244 vm_page_lock_queues(); 2245 pmap_protect(src_map->pmap, 2246 src_entry->start, 2247 src_entry->end, 2248 src_entry->protection & ~VM_PROT_WRITE); 2249 vm_page_unlock_queues(); 2250 } 2251 2252 /* 2253 * Make a copy of the object. 2254 */ 2255 if ((src_object = src_entry->object.vm_object) != NULL) { 2256 2257 if ((src_object->handle == NULL) && 2258 (src_object->type == OBJT_DEFAULT || 2259 src_object->type == OBJT_SWAP)) { 2260 vm_object_collapse(src_object); 2261 if ((src_object->flags & (OBJ_NOSPLIT|OBJ_ONEMAPPING)) == OBJ_ONEMAPPING) { 2262 vm_object_split(src_entry); 2263 src_object = src_entry->object.vm_object; 2264 } 2265 } 2266 2267 vm_object_reference(src_object); 2268 vm_object_lock(src_object); 2269 vm_object_clear_flag(src_object, OBJ_ONEMAPPING); 2270 vm_object_unlock(src_object); 2271 dst_entry->object.vm_object = src_object; 2272 src_entry->eflags |= (MAP_ENTRY_COW|MAP_ENTRY_NEEDS_COPY); 2273 dst_entry->eflags |= (MAP_ENTRY_COW|MAP_ENTRY_NEEDS_COPY); 2274 dst_entry->offset = src_entry->offset; 2275 } else { 2276 dst_entry->object.vm_object = NULL; 2277 dst_entry->offset = 0; 2278 } 2279 2280 pmap_copy(dst_map->pmap, src_map->pmap, dst_entry->start, 2281 dst_entry->end - dst_entry->start, src_entry->start); 2282 } else { 2283 /* 2284 * Of course, wired down pages can't be set copy-on-write. 2285 * Cause wired pages to be copied into the new map by 2286 * simulating faults (the new pages are pageable) 2287 */ 2288 vm_fault_copy_entry(dst_map, src_map, dst_entry, src_entry); 2289 } 2290 } 2291 2292 /* 2293 * vmspace_fork: 2294 * Create a new process vmspace structure and vm_map 2295 * based on those of an existing process. The new map 2296 * is based on the old map, according to the inheritance 2297 * values on the regions in that map. 2298 * 2299 * The source map must not be locked. 2300 */ 2301 struct vmspace * 2302 vmspace_fork(struct vmspace *vm1) 2303 { 2304 struct vmspace *vm2; 2305 vm_map_t old_map = &vm1->vm_map; 2306 vm_map_t new_map; 2307 vm_map_entry_t old_entry; 2308 vm_map_entry_t new_entry; 2309 vm_object_t object; 2310 2311 GIANT_REQUIRED; 2312 2313 vm_map_lock(old_map); 2314 old_map->infork = 1; 2315 2316 vm2 = vmspace_alloc(old_map->min_offset, old_map->max_offset); 2317 bcopy(&vm1->vm_startcopy, &vm2->vm_startcopy, 2318 (caddr_t) &vm1->vm_endcopy - (caddr_t) &vm1->vm_startcopy); 2319 new_map = &vm2->vm_map; /* XXX */ 2320 new_map->timestamp = 1; 2321 2322 old_entry = old_map->header.next; 2323 2324 while (old_entry != &old_map->header) { 2325 if (old_entry->eflags & MAP_ENTRY_IS_SUB_MAP) 2326 panic("vm_map_fork: encountered a submap"); 2327 2328 switch (old_entry->inheritance) { 2329 case VM_INHERIT_NONE: 2330 break; 2331 2332 case VM_INHERIT_SHARE: 2333 /* 2334 * Clone the entry, creating the shared object if necessary. 2335 */ 2336 object = old_entry->object.vm_object; 2337 if (object == NULL) { 2338 object = vm_object_allocate(OBJT_DEFAULT, 2339 atop(old_entry->end - old_entry->start)); 2340 old_entry->object.vm_object = object; 2341 old_entry->offset = (vm_offset_t) 0; 2342 } 2343 2344 /* 2345 * Add the reference before calling vm_object_shadow 2346 * to insure that a shadow object is created. 2347 */ 2348 vm_object_reference(object); 2349 if (old_entry->eflags & MAP_ENTRY_NEEDS_COPY) { 2350 vm_object_shadow(&old_entry->object.vm_object, 2351 &old_entry->offset, 2352 atop(old_entry->end - old_entry->start)); 2353 old_entry->eflags &= ~MAP_ENTRY_NEEDS_COPY; 2354 /* Transfer the second reference too. */ 2355 vm_object_reference( 2356 old_entry->object.vm_object); 2357 vm_object_deallocate(object); 2358 object = old_entry->object.vm_object; 2359 } 2360 vm_object_lock(object); 2361 vm_object_clear_flag(object, OBJ_ONEMAPPING); 2362 vm_object_unlock(object); 2363 2364 /* 2365 * Clone the entry, referencing the shared object. 2366 */ 2367 new_entry = vm_map_entry_create(new_map); 2368 *new_entry = *old_entry; 2369 new_entry->eflags &= ~MAP_ENTRY_USER_WIRED; 2370 new_entry->wired_count = 0; 2371 2372 /* 2373 * Insert the entry into the new map -- we know we're 2374 * inserting at the end of the new map. 2375 */ 2376 vm_map_entry_link(new_map, new_map->header.prev, 2377 new_entry); 2378 2379 /* 2380 * Update the physical map 2381 */ 2382 pmap_copy(new_map->pmap, old_map->pmap, 2383 new_entry->start, 2384 (old_entry->end - old_entry->start), 2385 old_entry->start); 2386 break; 2387 2388 case VM_INHERIT_COPY: 2389 /* 2390 * Clone the entry and link into the map. 2391 */ 2392 new_entry = vm_map_entry_create(new_map); 2393 *new_entry = *old_entry; 2394 new_entry->eflags &= ~MAP_ENTRY_USER_WIRED; 2395 new_entry->wired_count = 0; 2396 new_entry->object.vm_object = NULL; 2397 vm_map_entry_link(new_map, new_map->header.prev, 2398 new_entry); 2399 vm_map_copy_entry(old_map, new_map, old_entry, 2400 new_entry); 2401 break; 2402 } 2403 old_entry = old_entry->next; 2404 } 2405 2406 new_map->size = old_map->size; 2407 old_map->infork = 0; 2408 vm_map_unlock(old_map); 2409 2410 return (vm2); 2411 } 2412 2413 int 2414 vm_map_stack (vm_map_t map, vm_offset_t addrbos, vm_size_t max_ssize, 2415 vm_prot_t prot, vm_prot_t max, int cow) 2416 { 2417 vm_map_entry_t prev_entry; 2418 vm_map_entry_t new_stack_entry; 2419 vm_size_t init_ssize; 2420 int rv; 2421 2422 if (addrbos < vm_map_min(map)) 2423 return (KERN_NO_SPACE); 2424 2425 if (max_ssize < sgrowsiz) 2426 init_ssize = max_ssize; 2427 else 2428 init_ssize = sgrowsiz; 2429 2430 vm_map_lock(map); 2431 2432 /* If addr is already mapped, no go */ 2433 if (vm_map_lookup_entry(map, addrbos, &prev_entry)) { 2434 vm_map_unlock(map); 2435 return (KERN_NO_SPACE); 2436 } 2437 2438 /* If we would blow our VMEM resource limit, no go */ 2439 if (map->size + init_ssize > 2440 curthread->td_proc->p_rlimit[RLIMIT_VMEM].rlim_cur) { 2441 vm_map_unlock(map); 2442 return (KERN_NO_SPACE); 2443 } 2444 2445 /* If we can't accomodate max_ssize in the current mapping, 2446 * no go. However, we need to be aware that subsequent user 2447 * mappings might map into the space we have reserved for 2448 * stack, and currently this space is not protected. 2449 * 2450 * Hopefully we will at least detect this condition 2451 * when we try to grow the stack. 2452 */ 2453 if ((prev_entry->next != &map->header) && 2454 (prev_entry->next->start < addrbos + max_ssize)) { 2455 vm_map_unlock(map); 2456 return (KERN_NO_SPACE); 2457 } 2458 2459 /* We initially map a stack of only init_ssize. We will 2460 * grow as needed later. Since this is to be a grow 2461 * down stack, we map at the top of the range. 2462 * 2463 * Note: we would normally expect prot and max to be 2464 * VM_PROT_ALL, and cow to be 0. Possibly we should 2465 * eliminate these as input parameters, and just 2466 * pass these values here in the insert call. 2467 */ 2468 rv = vm_map_insert(map, NULL, 0, addrbos + max_ssize - init_ssize, 2469 addrbos + max_ssize, prot, max, cow); 2470 2471 /* Now set the avail_ssize amount */ 2472 if (rv == KERN_SUCCESS){ 2473 if (prev_entry != &map->header) 2474 vm_map_clip_end(map, prev_entry, addrbos + max_ssize - init_ssize); 2475 new_stack_entry = prev_entry->next; 2476 if (new_stack_entry->end != addrbos + max_ssize || 2477 new_stack_entry->start != addrbos + max_ssize - init_ssize) 2478 panic ("Bad entry start/end for new stack entry"); 2479 else 2480 new_stack_entry->avail_ssize = max_ssize - init_ssize; 2481 } 2482 2483 vm_map_unlock(map); 2484 return (rv); 2485 } 2486 2487 /* Attempts to grow a vm stack entry. Returns KERN_SUCCESS if the 2488 * desired address is already mapped, or if we successfully grow 2489 * the stack. Also returns KERN_SUCCESS if addr is outside the 2490 * stack range (this is strange, but preserves compatibility with 2491 * the grow function in vm_machdep.c). 2492 */ 2493 int 2494 vm_map_growstack (struct proc *p, vm_offset_t addr) 2495 { 2496 vm_map_entry_t prev_entry; 2497 vm_map_entry_t stack_entry; 2498 vm_map_entry_t new_stack_entry; 2499 struct vmspace *vm = p->p_vmspace; 2500 vm_map_t map = &vm->vm_map; 2501 vm_offset_t end; 2502 int grow_amount; 2503 int rv; 2504 int is_procstack; 2505 2506 GIANT_REQUIRED; 2507 2508 Retry: 2509 vm_map_lock_read(map); 2510 2511 /* If addr is already in the entry range, no need to grow.*/ 2512 if (vm_map_lookup_entry(map, addr, &prev_entry)) { 2513 vm_map_unlock_read(map); 2514 return (KERN_SUCCESS); 2515 } 2516 2517 if ((stack_entry = prev_entry->next) == &map->header) { 2518 vm_map_unlock_read(map); 2519 return (KERN_SUCCESS); 2520 } 2521 if (prev_entry == &map->header) 2522 end = stack_entry->start - stack_entry->avail_ssize; 2523 else 2524 end = prev_entry->end; 2525 2526 /* This next test mimics the old grow function in vm_machdep.c. 2527 * It really doesn't quite make sense, but we do it anyway 2528 * for compatibility. 2529 * 2530 * If not growable stack, return success. This signals the 2531 * caller to proceed as he would normally with normal vm. 2532 */ 2533 if (stack_entry->avail_ssize < 1 || 2534 addr >= stack_entry->start || 2535 addr < stack_entry->start - stack_entry->avail_ssize) { 2536 vm_map_unlock_read(map); 2537 return (KERN_SUCCESS); 2538 } 2539 2540 /* Find the minimum grow amount */ 2541 grow_amount = roundup (stack_entry->start - addr, PAGE_SIZE); 2542 if (grow_amount > stack_entry->avail_ssize) { 2543 vm_map_unlock_read(map); 2544 return (KERN_NO_SPACE); 2545 } 2546 2547 /* If there is no longer enough space between the entries 2548 * nogo, and adjust the available space. Note: this 2549 * should only happen if the user has mapped into the 2550 * stack area after the stack was created, and is 2551 * probably an error. 2552 * 2553 * This also effectively destroys any guard page the user 2554 * might have intended by limiting the stack size. 2555 */ 2556 if (grow_amount > stack_entry->start - end) { 2557 if (vm_map_lock_upgrade(map)) 2558 goto Retry; 2559 2560 stack_entry->avail_ssize = stack_entry->start - end; 2561 2562 vm_map_unlock(map); 2563 return (KERN_NO_SPACE); 2564 } 2565 2566 is_procstack = addr >= (vm_offset_t)vm->vm_maxsaddr; 2567 2568 /* If this is the main process stack, see if we're over the 2569 * stack limit. 2570 */ 2571 if (is_procstack && (ctob(vm->vm_ssize) + grow_amount > 2572 p->p_rlimit[RLIMIT_STACK].rlim_cur)) { 2573 vm_map_unlock_read(map); 2574 return (KERN_NO_SPACE); 2575 } 2576 2577 /* Round up the grow amount modulo SGROWSIZ */ 2578 grow_amount = roundup (grow_amount, sgrowsiz); 2579 if (grow_amount > stack_entry->avail_ssize) { 2580 grow_amount = stack_entry->avail_ssize; 2581 } 2582 if (is_procstack && (ctob(vm->vm_ssize) + grow_amount > 2583 p->p_rlimit[RLIMIT_STACK].rlim_cur)) { 2584 grow_amount = p->p_rlimit[RLIMIT_STACK].rlim_cur - 2585 ctob(vm->vm_ssize); 2586 } 2587 2588 /* If we would blow our VMEM resource limit, no go */ 2589 if (map->size + grow_amount > 2590 curthread->td_proc->p_rlimit[RLIMIT_VMEM].rlim_cur) { 2591 vm_map_unlock_read(map); 2592 return (KERN_NO_SPACE); 2593 } 2594 2595 if (vm_map_lock_upgrade(map)) 2596 goto Retry; 2597 2598 /* Get the preliminary new entry start value */ 2599 addr = stack_entry->start - grow_amount; 2600 2601 /* If this puts us into the previous entry, cut back our growth 2602 * to the available space. Also, see the note above. 2603 */ 2604 if (addr < end) { 2605 stack_entry->avail_ssize = stack_entry->start - end; 2606 addr = end; 2607 } 2608 2609 rv = vm_map_insert(map, NULL, 0, addr, stack_entry->start, 2610 p->p_sysent->sv_stackprot, VM_PROT_ALL, 0); 2611 2612 /* Adjust the available stack space by the amount we grew. */ 2613 if (rv == KERN_SUCCESS) { 2614 if (prev_entry != &map->header) 2615 vm_map_clip_end(map, prev_entry, addr); 2616 new_stack_entry = prev_entry->next; 2617 if (new_stack_entry->end != stack_entry->start || 2618 new_stack_entry->start != addr) 2619 panic ("Bad stack grow start/end in new stack entry"); 2620 else { 2621 new_stack_entry->avail_ssize = stack_entry->avail_ssize - 2622 (new_stack_entry->end - 2623 new_stack_entry->start); 2624 if (is_procstack) 2625 vm->vm_ssize += btoc(new_stack_entry->end - 2626 new_stack_entry->start); 2627 } 2628 } 2629 2630 vm_map_unlock(map); 2631 return (rv); 2632 } 2633 2634 /* 2635 * Unshare the specified VM space for exec. If other processes are 2636 * mapped to it, then create a new one. The new vmspace is null. 2637 */ 2638 void 2639 vmspace_exec(struct proc *p, vm_offset_t minuser, vm_offset_t maxuser) 2640 { 2641 struct vmspace *oldvmspace = p->p_vmspace; 2642 struct vmspace *newvmspace; 2643 2644 GIANT_REQUIRED; 2645 newvmspace = vmspace_alloc(minuser, maxuser); 2646 bcopy(&oldvmspace->vm_startcopy, &newvmspace->vm_startcopy, 2647 (caddr_t) (newvmspace + 1) - (caddr_t) &newvmspace->vm_startcopy); 2648 /* 2649 * This code is written like this for prototype purposes. The 2650 * goal is to avoid running down the vmspace here, but let the 2651 * other process's that are still using the vmspace to finally 2652 * run it down. Even though there is little or no chance of blocking 2653 * here, it is a good idea to keep this form for future mods. 2654 */ 2655 p->p_vmspace = newvmspace; 2656 pmap_pinit2(vmspace_pmap(newvmspace)); 2657 vmspace_free(oldvmspace); 2658 if (p == curthread->td_proc) /* XXXKSE ? */ 2659 pmap_activate(curthread); 2660 } 2661 2662 /* 2663 * Unshare the specified VM space for forcing COW. This 2664 * is called by rfork, for the (RFMEM|RFPROC) == 0 case. 2665 */ 2666 void 2667 vmspace_unshare(struct proc *p) 2668 { 2669 struct vmspace *oldvmspace = p->p_vmspace; 2670 struct vmspace *newvmspace; 2671 2672 GIANT_REQUIRED; 2673 if (oldvmspace->vm_refcnt == 1) 2674 return; 2675 newvmspace = vmspace_fork(oldvmspace); 2676 p->p_vmspace = newvmspace; 2677 pmap_pinit2(vmspace_pmap(newvmspace)); 2678 vmspace_free(oldvmspace); 2679 if (p == curthread->td_proc) /* XXXKSE ? */ 2680 pmap_activate(curthread); 2681 } 2682 2683 /* 2684 * vm_map_lookup: 2685 * 2686 * Finds the VM object, offset, and 2687 * protection for a given virtual address in the 2688 * specified map, assuming a page fault of the 2689 * type specified. 2690 * 2691 * Leaves the map in question locked for read; return 2692 * values are guaranteed until a vm_map_lookup_done 2693 * call is performed. Note that the map argument 2694 * is in/out; the returned map must be used in 2695 * the call to vm_map_lookup_done. 2696 * 2697 * A handle (out_entry) is returned for use in 2698 * vm_map_lookup_done, to make that fast. 2699 * 2700 * If a lookup is requested with "write protection" 2701 * specified, the map may be changed to perform virtual 2702 * copying operations, although the data referenced will 2703 * remain the same. 2704 */ 2705 int 2706 vm_map_lookup(vm_map_t *var_map, /* IN/OUT */ 2707 vm_offset_t vaddr, 2708 vm_prot_t fault_typea, 2709 vm_map_entry_t *out_entry, /* OUT */ 2710 vm_object_t *object, /* OUT */ 2711 vm_pindex_t *pindex, /* OUT */ 2712 vm_prot_t *out_prot, /* OUT */ 2713 boolean_t *wired) /* OUT */ 2714 { 2715 vm_map_entry_t entry; 2716 vm_map_t map = *var_map; 2717 vm_prot_t prot; 2718 vm_prot_t fault_type = fault_typea; 2719 2720 RetryLookup:; 2721 /* 2722 * Lookup the faulting address. 2723 */ 2724 2725 vm_map_lock_read(map); 2726 #define RETURN(why) \ 2727 { \ 2728 vm_map_unlock_read(map); \ 2729 return (why); \ 2730 } 2731 2732 /* 2733 * If the map has an interesting hint, try it before calling full 2734 * blown lookup routine. 2735 */ 2736 entry = map->root; 2737 *out_entry = entry; 2738 if (entry == NULL || 2739 (vaddr < entry->start) || (vaddr >= entry->end)) { 2740 /* 2741 * Entry was either not a valid hint, or the vaddr was not 2742 * contained in the entry, so do a full lookup. 2743 */ 2744 if (!vm_map_lookup_entry(map, vaddr, out_entry)) 2745 RETURN(KERN_INVALID_ADDRESS); 2746 2747 entry = *out_entry; 2748 } 2749 2750 /* 2751 * Handle submaps. 2752 */ 2753 if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) { 2754 vm_map_t old_map = map; 2755 2756 *var_map = map = entry->object.sub_map; 2757 vm_map_unlock_read(old_map); 2758 goto RetryLookup; 2759 } 2760 2761 /* 2762 * Check whether this task is allowed to have this page. 2763 * Note the special case for MAP_ENTRY_COW 2764 * pages with an override. This is to implement a forced 2765 * COW for debuggers. 2766 */ 2767 if (fault_type & VM_PROT_OVERRIDE_WRITE) 2768 prot = entry->max_protection; 2769 else 2770 prot = entry->protection; 2771 fault_type &= (VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 2772 if ((fault_type & prot) != fault_type) { 2773 RETURN(KERN_PROTECTION_FAILURE); 2774 } 2775 if ((entry->eflags & MAP_ENTRY_USER_WIRED) && 2776 (entry->eflags & MAP_ENTRY_COW) && 2777 (fault_type & VM_PROT_WRITE) && 2778 (fault_typea & VM_PROT_OVERRIDE_WRITE) == 0) { 2779 RETURN(KERN_PROTECTION_FAILURE); 2780 } 2781 2782 /* 2783 * If this page is not pageable, we have to get it for all possible 2784 * accesses. 2785 */ 2786 *wired = (entry->wired_count != 0); 2787 if (*wired) 2788 prot = fault_type = entry->protection; 2789 2790 /* 2791 * If the entry was copy-on-write, we either ... 2792 */ 2793 if (entry->eflags & MAP_ENTRY_NEEDS_COPY) { 2794 /* 2795 * If we want to write the page, we may as well handle that 2796 * now since we've got the map locked. 2797 * 2798 * If we don't need to write the page, we just demote the 2799 * permissions allowed. 2800 */ 2801 if (fault_type & VM_PROT_WRITE) { 2802 /* 2803 * Make a new object, and place it in the object 2804 * chain. Note that no new references have appeared 2805 * -- one just moved from the map to the new 2806 * object. 2807 */ 2808 if (vm_map_lock_upgrade(map)) 2809 goto RetryLookup; 2810 2811 vm_object_shadow( 2812 &entry->object.vm_object, 2813 &entry->offset, 2814 atop(entry->end - entry->start)); 2815 entry->eflags &= ~MAP_ENTRY_NEEDS_COPY; 2816 2817 vm_map_lock_downgrade(map); 2818 } else { 2819 /* 2820 * We're attempting to read a copy-on-write page -- 2821 * don't allow writes. 2822 */ 2823 prot &= ~VM_PROT_WRITE; 2824 } 2825 } 2826 2827 /* 2828 * Create an object if necessary. 2829 */ 2830 if (entry->object.vm_object == NULL && 2831 !map->system_map) { 2832 if (vm_map_lock_upgrade(map)) 2833 goto RetryLookup; 2834 entry->object.vm_object = vm_object_allocate(OBJT_DEFAULT, 2835 atop(entry->end - entry->start)); 2836 entry->offset = 0; 2837 vm_map_lock_downgrade(map); 2838 } 2839 2840 /* 2841 * Return the object/offset from this entry. If the entry was 2842 * copy-on-write or empty, it has been fixed up. 2843 */ 2844 *pindex = OFF_TO_IDX((vaddr - entry->start) + entry->offset); 2845 *object = entry->object.vm_object; 2846 2847 /* 2848 * Return whether this is the only map sharing this data. 2849 */ 2850 *out_prot = prot; 2851 return (KERN_SUCCESS); 2852 2853 #undef RETURN 2854 } 2855 2856 /* 2857 * vm_map_lookup_done: 2858 * 2859 * Releases locks acquired by a vm_map_lookup 2860 * (according to the handle returned by that lookup). 2861 */ 2862 void 2863 vm_map_lookup_done(vm_map_t map, vm_map_entry_t entry) 2864 { 2865 /* 2866 * Unlock the main-level map 2867 */ 2868 vm_map_unlock_read(map); 2869 } 2870 2871 #ifdef ENABLE_VFS_IOOPT 2872 /* 2873 * Experimental support for zero-copy I/O 2874 * 2875 * Implement uiomove with VM operations. This handles (and collateral changes) 2876 * support every combination of source object modification, and COW type 2877 * operations. 2878 */ 2879 int 2880 vm_uiomove( 2881 vm_map_t mapa, 2882 vm_object_t srcobject, 2883 off_t cp, 2884 int cnta, 2885 vm_offset_t uaddra, 2886 int *npages) 2887 { 2888 vm_map_t map; 2889 vm_object_t first_object, oldobject, object; 2890 vm_map_entry_t entry; 2891 vm_prot_t prot; 2892 boolean_t wired; 2893 int tcnt, rv; 2894 vm_offset_t uaddr, start, end, tend; 2895 vm_pindex_t first_pindex, oindex; 2896 vm_size_t osize; 2897 off_t ooffset; 2898 int cnt; 2899 2900 GIANT_REQUIRED; 2901 2902 if (npages) 2903 *npages = 0; 2904 2905 cnt = cnta; 2906 uaddr = uaddra; 2907 2908 while (cnt > 0) { 2909 map = mapa; 2910 2911 if ((vm_map_lookup(&map, uaddr, 2912 VM_PROT_READ, &entry, &first_object, 2913 &first_pindex, &prot, &wired)) != KERN_SUCCESS) { 2914 return EFAULT; 2915 } 2916 2917 vm_map_clip_start(map, entry, uaddr); 2918 2919 tcnt = cnt; 2920 tend = uaddr + tcnt; 2921 if (tend > entry->end) { 2922 tcnt = entry->end - uaddr; 2923 tend = entry->end; 2924 } 2925 2926 vm_map_clip_end(map, entry, tend); 2927 2928 start = entry->start; 2929 end = entry->end; 2930 2931 osize = atop(tcnt); 2932 2933 oindex = OFF_TO_IDX(cp); 2934 if (npages) { 2935 vm_size_t idx; 2936 for (idx = 0; idx < osize; idx++) { 2937 vm_page_t m; 2938 if ((m = vm_page_lookup(srcobject, oindex + idx)) == NULL) { 2939 vm_map_lookup_done(map, entry); 2940 return 0; 2941 } 2942 /* 2943 * disallow busy or invalid pages, but allow 2944 * m->busy pages if they are entirely valid. 2945 */ 2946 if ((m->flags & PG_BUSY) || 2947 ((m->valid & VM_PAGE_BITS_ALL) != VM_PAGE_BITS_ALL)) { 2948 vm_map_lookup_done(map, entry); 2949 return 0; 2950 } 2951 } 2952 } 2953 2954 /* 2955 * If we are changing an existing map entry, just redirect 2956 * the object, and change mappings. 2957 */ 2958 if ((first_object->type == OBJT_VNODE) && 2959 ((oldobject = entry->object.vm_object) == first_object)) { 2960 2961 if ((entry->offset != cp) || (oldobject != srcobject)) { 2962 /* 2963 * Remove old window into the file 2964 */ 2965 vm_page_lock_queues(); 2966 pmap_remove(map->pmap, uaddr, tend); 2967 vm_page_unlock_queues(); 2968 2969 /* 2970 * Force copy on write for mmaped regions 2971 */ 2972 vm_object_pmap_copy_1 (srcobject, oindex, oindex + osize); 2973 2974 /* 2975 * Point the object appropriately 2976 */ 2977 if (oldobject != srcobject) { 2978 2979 /* 2980 * Set the object optimization hint flag 2981 */ 2982 vm_object_set_flag(srcobject, OBJ_OPT); 2983 vm_object_reference(srcobject); 2984 entry->object.vm_object = srcobject; 2985 2986 if (oldobject) { 2987 vm_object_deallocate(oldobject); 2988 } 2989 } 2990 2991 entry->offset = cp; 2992 map->timestamp++; 2993 } else { 2994 vm_page_lock_queues(); 2995 pmap_remove(map->pmap, uaddr, tend); 2996 vm_page_unlock_queues(); 2997 } 2998 2999 } else if ((first_object->ref_count == 1) && 3000 (first_object->size == osize) && 3001 ((first_object->type == OBJT_DEFAULT) || 3002 (first_object->type == OBJT_SWAP)) ) { 3003 3004 oldobject = first_object->backing_object; 3005 3006 if ((first_object->backing_object_offset != cp) || 3007 (oldobject != srcobject)) { 3008 /* 3009 * Remove old window into the file 3010 */ 3011 vm_page_lock_queues(); 3012 pmap_remove(map->pmap, uaddr, tend); 3013 vm_page_unlock_queues(); 3014 3015 /* 3016 * Remove unneeded old pages 3017 */ 3018 vm_object_lock(first_object); 3019 vm_object_page_remove(first_object, 0, 0, 0); 3020 vm_object_unlock(first_object); 3021 3022 /* 3023 * Invalidate swap space 3024 */ 3025 if (first_object->type == OBJT_SWAP) { 3026 swap_pager_freespace(first_object, 3027 0, 3028 first_object->size); 3029 } 3030 3031 /* 3032 * Force copy on write for mmaped regions 3033 */ 3034 vm_object_pmap_copy_1 (srcobject, oindex, oindex + osize); 3035 3036 /* 3037 * Point the object appropriately 3038 */ 3039 if (oldobject != srcobject) { 3040 /* 3041 * Set the object optimization hint flag 3042 */ 3043 vm_object_set_flag(srcobject, OBJ_OPT); 3044 vm_object_reference(srcobject); 3045 3046 if (oldobject) { 3047 TAILQ_REMOVE(&oldobject->shadow_head, 3048 first_object, shadow_list); 3049 oldobject->shadow_count--; 3050 /* XXX bump generation? */ 3051 vm_object_deallocate(oldobject); 3052 } 3053 3054 TAILQ_INSERT_TAIL(&srcobject->shadow_head, 3055 first_object, shadow_list); 3056 srcobject->shadow_count++; 3057 /* XXX bump generation? */ 3058 3059 first_object->backing_object = srcobject; 3060 } 3061 first_object->backing_object_offset = cp; 3062 map->timestamp++; 3063 } else { 3064 vm_page_lock_queues(); 3065 pmap_remove(map->pmap, uaddr, tend); 3066 vm_page_unlock_queues(); 3067 } 3068 /* 3069 * Otherwise, we have to do a logical mmap. 3070 */ 3071 } else { 3072 3073 vm_object_set_flag(srcobject, OBJ_OPT); 3074 vm_object_reference(srcobject); 3075 3076 vm_page_lock_queues(); 3077 pmap_remove(map->pmap, uaddr, tend); 3078 vm_page_unlock_queues(); 3079 3080 vm_object_pmap_copy_1 (srcobject, oindex, oindex + osize); 3081 vm_map_lock_upgrade(map); 3082 3083 if (entry == &map->header) { 3084 map->first_free = &map->header; 3085 } else if (map->first_free->start >= start) { 3086 map->first_free = entry->prev; 3087 } 3088 3089 vm_map_entry_delete(map, entry); 3090 3091 object = srcobject; 3092 ooffset = cp; 3093 3094 rv = vm_map_insert(map, object, ooffset, start, tend, 3095 VM_PROT_ALL, VM_PROT_ALL, MAP_COPY_ON_WRITE); 3096 3097 if (rv != KERN_SUCCESS) 3098 panic("vm_uiomove: could not insert new entry: %d", rv); 3099 } 3100 3101 /* 3102 * Map the window directly, if it is already in memory 3103 */ 3104 pmap_object_init_pt(map->pmap, uaddr, 3105 srcobject, oindex, tcnt, 0); 3106 3107 map->timestamp++; 3108 vm_map_unlock(map); 3109 3110 cnt -= tcnt; 3111 uaddr += tcnt; 3112 cp += tcnt; 3113 if (npages) 3114 *npages += osize; 3115 } 3116 return 0; 3117 } 3118 #endif 3119 3120 #include "opt_ddb.h" 3121 #ifdef DDB 3122 #include <sys/kernel.h> 3123 3124 #include <ddb/ddb.h> 3125 3126 /* 3127 * vm_map_print: [ debug ] 3128 */ 3129 DB_SHOW_COMMAND(map, vm_map_print) 3130 { 3131 static int nlines; 3132 /* XXX convert args. */ 3133 vm_map_t map = (vm_map_t)addr; 3134 boolean_t full = have_addr; 3135 3136 vm_map_entry_t entry; 3137 3138 db_iprintf("Task map %p: pmap=%p, nentries=%d, version=%u\n", 3139 (void *)map, 3140 (void *)map->pmap, map->nentries, map->timestamp); 3141 nlines++; 3142 3143 if (!full && db_indent) 3144 return; 3145 3146 db_indent += 2; 3147 for (entry = map->header.next; entry != &map->header; 3148 entry = entry->next) { 3149 db_iprintf("map entry %p: start=%p, end=%p\n", 3150 (void *)entry, (void *)entry->start, (void *)entry->end); 3151 nlines++; 3152 { 3153 static char *inheritance_name[4] = 3154 {"share", "copy", "none", "donate_copy"}; 3155 3156 db_iprintf(" prot=%x/%x/%s", 3157 entry->protection, 3158 entry->max_protection, 3159 inheritance_name[(int)(unsigned char)entry->inheritance]); 3160 if (entry->wired_count != 0) 3161 db_printf(", wired"); 3162 } 3163 if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) { 3164 db_printf(", share=%p, offset=0x%jx\n", 3165 (void *)entry->object.sub_map, 3166 (uintmax_t)entry->offset); 3167 nlines++; 3168 if ((entry->prev == &map->header) || 3169 (entry->prev->object.sub_map != 3170 entry->object.sub_map)) { 3171 db_indent += 2; 3172 vm_map_print((db_expr_t)(intptr_t) 3173 entry->object.sub_map, 3174 full, 0, (char *)0); 3175 db_indent -= 2; 3176 } 3177 } else { 3178 db_printf(", object=%p, offset=0x%jx", 3179 (void *)entry->object.vm_object, 3180 (uintmax_t)entry->offset); 3181 if (entry->eflags & MAP_ENTRY_COW) 3182 db_printf(", copy (%s)", 3183 (entry->eflags & MAP_ENTRY_NEEDS_COPY) ? "needed" : "done"); 3184 db_printf("\n"); 3185 nlines++; 3186 3187 if ((entry->prev == &map->header) || 3188 (entry->prev->object.vm_object != 3189 entry->object.vm_object)) { 3190 db_indent += 2; 3191 vm_object_print((db_expr_t)(intptr_t) 3192 entry->object.vm_object, 3193 full, 0, (char *)0); 3194 nlines += 4; 3195 db_indent -= 2; 3196 } 3197 } 3198 } 3199 db_indent -= 2; 3200 if (db_indent == 0) 3201 nlines = 0; 3202 } 3203 3204 3205 DB_SHOW_COMMAND(procvm, procvm) 3206 { 3207 struct proc *p; 3208 3209 if (have_addr) { 3210 p = (struct proc *) addr; 3211 } else { 3212 p = curproc; 3213 } 3214 3215 db_printf("p = %p, vmspace = %p, map = %p, pmap = %p\n", 3216 (void *)p, (void *)p->p_vmspace, (void *)&p->p_vmspace->vm_map, 3217 (void *)vmspace_pmap(p->p_vmspace)); 3218 3219 vm_map_print((db_expr_t)(intptr_t)&p->p_vmspace->vm_map, 1, 0, NULL); 3220 } 3221 3222 #endif /* DDB */ 3223