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: src/sys/vm/vm_map.c,v 1.187.2.19 2003/05/27 00:47:02 alc Exp $ 65 * $DragonFly: src/sys/vm/vm_map.c,v 1.27 2004/05/13 17:40:19 dillon Exp $ 66 */ 67 68 /* 69 * Virtual memory mapping module. 70 */ 71 72 #include <sys/param.h> 73 #include <sys/systm.h> 74 #include <sys/proc.h> 75 #include <sys/lock.h> 76 #include <sys/vmmeter.h> 77 #include <sys/mman.h> 78 #include <sys/vnode.h> 79 #include <sys/resourcevar.h> 80 #include <sys/shm.h> 81 82 #include <vm/vm.h> 83 #include <vm/vm_param.h> 84 #include <vm/pmap.h> 85 #include <vm/vm_map.h> 86 #include <vm/vm_page.h> 87 #include <vm/vm_object.h> 88 #include <vm/vm_pager.h> 89 #include <vm/vm_kern.h> 90 #include <vm/vm_extern.h> 91 #include <vm/swap_pager.h> 92 #include <vm/vm_zone.h> 93 94 #include <sys/thread2.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 vm_zone mapentzone_store, mapzone_store; 137 static vm_zone_t mapentzone, mapzone, vmspace_zone; 138 static struct vm_object mapentobj, mapobj; 139 140 static struct vm_map_entry map_entry_init[MAX_MAPENT]; 141 static struct vm_map map_init[MAX_KMAP]; 142 143 static vm_map_entry_t vm_map_entry_create(vm_map_t map, int *); 144 static void vm_map_entry_dispose (vm_map_t map, vm_map_entry_t entry, int *); 145 static void _vm_map_clip_end (vm_map_t, vm_map_entry_t, vm_offset_t, int *); 146 static void _vm_map_clip_start (vm_map_t, vm_map_entry_t, vm_offset_t, int *); 147 static void vm_map_entry_delete (vm_map_t, vm_map_entry_t, int *); 148 static void vm_map_entry_unwire (vm_map_t, vm_map_entry_t); 149 static void vm_map_copy_entry (vm_map_t, vm_map_t, vm_map_entry_t, 150 vm_map_entry_t); 151 static void vm_map_split (vm_map_entry_t); 152 static void vm_map_unclip_range (vm_map_t map, vm_map_entry_t start_entry, vm_offset_t start, vm_offset_t end, int *count, int flags); 153 154 void 155 vm_map_startup(void) 156 { 157 mapzone = &mapzone_store; 158 zbootinit(mapzone, "MAP", sizeof (struct vm_map), 159 map_init, MAX_KMAP); 160 mapentzone = &mapentzone_store; 161 zbootinit(mapentzone, "MAP ENTRY", sizeof (struct vm_map_entry), 162 map_entry_init, MAX_MAPENT); 163 } 164 165 /* 166 * Allocate a vmspace structure, including a vm_map and pmap, 167 * and initialize those structures. The refcnt is set to 1. 168 * The remaining fields must be initialized by the caller. 169 */ 170 struct vmspace * 171 vmspace_alloc(vm_offset_t min, vm_offset_t max) 172 { 173 struct vmspace *vm; 174 175 vm = zalloc(vmspace_zone); 176 vm_map_init(&vm->vm_map, min, max); 177 pmap_pinit(vmspace_pmap(vm)); 178 vm->vm_map.pmap = vmspace_pmap(vm); /* XXX */ 179 vm->vm_refcnt = 1; 180 vm->vm_shm = NULL; 181 vm->vm_exitingcnt = 0; 182 return (vm); 183 } 184 185 void 186 vm_init2(void) 187 { 188 zinitna(mapentzone, &mapentobj, NULL, 0, 0, ZONE_USE_RESERVE, 1); 189 zinitna(mapzone, &mapobj, NULL, 0, 0, 0, 1); 190 vmspace_zone = zinit("VMSPACE", sizeof (struct vmspace), 0, 0, 3); 191 pmap_init2(); 192 vm_object_init2(); 193 } 194 195 static __inline void 196 vmspace_dofree(struct vmspace *vm) 197 { 198 int count; 199 200 /* 201 * Make sure any SysV shm is freed, it might not have in 202 * exit1() 203 */ 204 shmexit(vm); 205 206 KKASSERT(vm->vm_upcalls == NULL); 207 208 /* 209 * Lock the map, to wait out all other references to it. 210 * Delete all of the mappings and pages they hold, then call 211 * the pmap module to reclaim anything left. 212 */ 213 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 214 vm_map_lock(&vm->vm_map); 215 vm_map_delete(&vm->vm_map, vm->vm_map.min_offset, 216 vm->vm_map.max_offset, &count); 217 vm_map_unlock(&vm->vm_map); 218 vm_map_entry_release(count); 219 220 pmap_release(vmspace_pmap(vm)); 221 zfree(vmspace_zone, vm); 222 } 223 224 void 225 vmspace_free(struct vmspace *vm) 226 { 227 if (vm->vm_refcnt == 0) 228 panic("vmspace_free: attempt to free already freed vmspace"); 229 230 if (--vm->vm_refcnt == 0 && vm->vm_exitingcnt == 0) 231 vmspace_dofree(vm); 232 } 233 234 void 235 vmspace_exitfree(struct proc *p) 236 { 237 struct vmspace *vm; 238 239 vm = p->p_vmspace; 240 p->p_vmspace = NULL; 241 242 /* 243 * cleanup by parent process wait()ing on exiting child. vm_refcnt 244 * may not be 0 (e.g. fork() and child exits without exec()ing). 245 * exitingcnt may increment above 0 and drop back down to zero 246 * several times while vm_refcnt is held non-zero. vm_refcnt 247 * may also increment above 0 and drop back down to zero several 248 * times while vm_exitingcnt is held non-zero. 249 * 250 * The last wait on the exiting child's vmspace will clean up 251 * the remainder of the vmspace. 252 */ 253 if (--vm->vm_exitingcnt == 0 && vm->vm_refcnt == 0) 254 vmspace_dofree(vm); 255 } 256 257 /* 258 * vmspace_swap_count() - count the approximate swap useage in pages for a 259 * vmspace. 260 * 261 * Swap useage is determined by taking the proportional swap used by 262 * VM objects backing the VM map. To make up for fractional losses, 263 * if the VM object has any swap use at all the associated map entries 264 * count for at least 1 swap page. 265 */ 266 int 267 vmspace_swap_count(struct vmspace *vmspace) 268 { 269 vm_map_t map = &vmspace->vm_map; 270 vm_map_entry_t cur; 271 int count = 0; 272 273 for (cur = map->header.next; cur != &map->header; cur = cur->next) { 274 vm_object_t object; 275 276 if ((cur->eflags & MAP_ENTRY_IS_SUB_MAP) == 0 && 277 (object = cur->object.vm_object) != NULL && 278 object->type == OBJT_SWAP 279 ) { 280 int n = (cur->end - cur->start) / PAGE_SIZE; 281 282 if (object->un_pager.swp.swp_bcount) { 283 count += object->un_pager.swp.swp_bcount * 284 SWAP_META_PAGES * n / object->size + 1; 285 } 286 } 287 } 288 return(count); 289 } 290 291 292 /* 293 * vm_map_create: 294 * 295 * Creates and returns a new empty VM map with 296 * the given physical map structure, and having 297 * the given lower and upper address bounds. 298 */ 299 vm_map_t 300 vm_map_create(pmap_t pmap, vm_offset_t min, vm_offset_t max) 301 { 302 vm_map_t result; 303 304 result = zalloc(mapzone); 305 vm_map_init(result, min, max); 306 result->pmap = pmap; 307 return (result); 308 } 309 310 /* 311 * Initialize an existing vm_map structure 312 * such as that in the vmspace structure. 313 * The pmap is set elsewhere. 314 */ 315 void 316 vm_map_init(struct vm_map *map, vm_offset_t min, vm_offset_t max) 317 { 318 map->header.next = map->header.prev = &map->header; 319 map->nentries = 0; 320 map->size = 0; 321 map->system_map = 0; 322 map->infork = 0; 323 map->min_offset = min; 324 map->max_offset = max; 325 map->first_free = &map->header; 326 map->hint = &map->header; 327 map->timestamp = 0; 328 lockinit(&map->lock, 0, "thrd_sleep", 0, LK_NOPAUSE); 329 } 330 331 /* 332 * vm_map_entry_cpu_init: 333 * 334 * Set an initial negative count so the first attempt to reserve 335 * space preloads a bunch of vm_map_entry's for this cpu. This 336 * routine is called in early boot so we cannot just call 337 * vm_map_entry_reserve(). 338 * 339 * May be called for a gd other then mycpu. 340 */ 341 void 342 vm_map_entry_reserve_cpu_init(globaldata_t gd) 343 { 344 gd->gd_vme_avail -= MAP_RESERVE_COUNT * 2; 345 } 346 347 /* 348 * vm_map_entry_reserve: 349 * 350 * Reserves vm_map_entry structures so code later on can manipulate 351 * map_entry structures within a locked map without blocking trying 352 * to allocate a new vm_map_entry. 353 */ 354 int 355 vm_map_entry_reserve(int count) 356 { 357 struct globaldata *gd = mycpu; 358 vm_map_entry_t entry; 359 360 crit_enter(); 361 gd->gd_vme_avail -= count; 362 363 /* 364 * Make sure we have enough structures in gd_vme_base to handle 365 * the reservation request. 366 */ 367 while (gd->gd_vme_avail < 0) { 368 entry = zalloc(mapentzone); 369 entry->next = gd->gd_vme_base; 370 gd->gd_vme_base = entry; 371 ++gd->gd_vme_avail; 372 } 373 crit_exit(); 374 return(count); 375 } 376 377 /* 378 * vm_map_entry_release: 379 * 380 * Releases previously reserved vm_map_entry structures that were not 381 * used. If we have too much junk in our per-cpu cache clean some of 382 * it out. 383 */ 384 void 385 vm_map_entry_release(int count) 386 { 387 struct globaldata *gd = mycpu; 388 vm_map_entry_t entry; 389 390 crit_enter(); 391 gd->gd_vme_avail += count; 392 while (gd->gd_vme_avail > MAP_RESERVE_SLOP) { 393 entry = gd->gd_vme_base; 394 KKASSERT(entry != NULL); 395 gd->gd_vme_base = entry->next; 396 --gd->gd_vme_avail; 397 crit_exit(); 398 zfree(mapentzone, entry); 399 crit_enter(); 400 } 401 crit_exit(); 402 } 403 404 /* 405 * vm_map_entry_kreserve: 406 * 407 * Reserve map entry structures for use in kernel_map or (if it exists) 408 * kmem_map. These entries have *ALREADY* been reserved on a per-cpu 409 * basis when the map was inited. This function is used by zalloc() 410 * to avoid a recursion when zalloc() itself needs to allocate additional 411 * kernel memory. 412 * 413 * This function should only be used when the caller intends to later 414 * call vm_map_entry_reserve() to 'normalize' the reserve cache. 415 */ 416 int 417 vm_map_entry_kreserve(int count) 418 { 419 struct globaldata *gd = mycpu; 420 421 crit_enter(); 422 gd->gd_vme_kdeficit += count; 423 crit_exit(); 424 KKASSERT(gd->gd_vme_base != NULL); 425 return(count); 426 } 427 428 /* 429 * vm_map_entry_krelease: 430 * 431 * Release previously reserved map entries for kernel_map or kmem_map 432 * use. This routine determines how many entries were actually used and 433 * replentishes the kernel reserve supply from vme_avail. 434 * 435 * If there is insufficient supply vme_avail will go negative, which is 436 * ok. We cannot safely call zalloc in this function without getting 437 * into a recursion deadlock. zalloc() will call vm_map_entry_reserve() 438 * to regenerate the lost entries. 439 */ 440 void 441 vm_map_entry_krelease(int count) 442 { 443 struct globaldata *gd = mycpu; 444 445 crit_enter(); 446 gd->gd_vme_kdeficit -= count; 447 gd->gd_vme_avail -= gd->gd_vme_kdeficit; /* can go negative */ 448 gd->gd_vme_kdeficit = 0; 449 crit_exit(); 450 } 451 452 /* 453 * vm_map_entry_create: [ internal use only ] 454 * 455 * Allocates a VM map entry for insertion. No entry fields are filled 456 * in. 457 * 458 * This routine may be called from an interrupt thread but not a FAST 459 * interrupt. This routine may recurse the map lock. 460 */ 461 static vm_map_entry_t 462 vm_map_entry_create(vm_map_t map, int *countp) 463 { 464 struct globaldata *gd = mycpu; 465 vm_map_entry_t entry; 466 467 KKASSERT(*countp > 0); 468 --*countp; 469 crit_enter(); 470 entry = gd->gd_vme_base; 471 KASSERT(entry != NULL, ("gd_vme_base NULL! count %d", *countp)); 472 gd->gd_vme_base = entry->next; 473 crit_exit(); 474 return(entry); 475 } 476 477 /* 478 * vm_map_entry_dispose: [ internal use only ] 479 * 480 * Dispose of a vm_map_entry that is no longer being referenced. This 481 * function may be called from an interrupt. 482 */ 483 static void 484 vm_map_entry_dispose(vm_map_t map, vm_map_entry_t entry, int *countp) 485 { 486 struct globaldata *gd = mycpu; 487 488 ++*countp; 489 crit_enter(); 490 entry->next = gd->gd_vme_base; 491 gd->gd_vme_base = entry; 492 crit_exit(); 493 } 494 495 496 /* 497 * vm_map_entry_{un,}link: 498 * 499 * Insert/remove entries from maps. 500 */ 501 static __inline void 502 vm_map_entry_link(vm_map_t map, 503 vm_map_entry_t after_where, 504 vm_map_entry_t entry) 505 { 506 map->nentries++; 507 entry->prev = after_where; 508 entry->next = after_where->next; 509 entry->next->prev = entry; 510 after_where->next = entry; 511 } 512 513 static __inline void 514 vm_map_entry_unlink(vm_map_t map, 515 vm_map_entry_t entry) 516 { 517 vm_map_entry_t prev; 518 vm_map_entry_t next; 519 520 if (entry->eflags & MAP_ENTRY_IN_TRANSITION) 521 panic("vm_map_entry_unlink: attempt to mess with locked entry! %p", entry); 522 prev = entry->prev; 523 next = entry->next; 524 next->prev = prev; 525 prev->next = next; 526 map->nentries--; 527 } 528 529 /* 530 * SAVE_HINT: 531 * 532 * Saves the specified entry as the hint for 533 * future lookups. 534 */ 535 #define SAVE_HINT(map,value) \ 536 (map)->hint = (value); 537 538 /* 539 * vm_map_lookup_entry: [ internal use only ] 540 * 541 * Finds the map entry containing (or 542 * immediately preceding) the specified address 543 * in the given map; the entry is returned 544 * in the "entry" parameter. The boolean 545 * result indicates whether the address is 546 * actually contained in the map. 547 */ 548 boolean_t 549 vm_map_lookup_entry(vm_map_t map, vm_offset_t address, 550 vm_map_entry_t *entry /* OUT */) 551 { 552 vm_map_entry_t cur; 553 vm_map_entry_t last; 554 555 /* 556 * Start looking either from the head of the list, or from the hint. 557 */ 558 559 cur = map->hint; 560 561 if (cur == &map->header) 562 cur = cur->next; 563 564 if (address >= cur->start) { 565 /* 566 * Go from hint to end of list. 567 * 568 * But first, make a quick check to see if we are already looking 569 * at the entry we want (which is usually the case). Note also 570 * that we don't need to save the hint here... it is the same 571 * hint (unless we are at the header, in which case the hint 572 * didn't buy us anything anyway). 573 */ 574 last = &map->header; 575 if ((cur != last) && (cur->end > address)) { 576 *entry = cur; 577 return (TRUE); 578 } 579 } else { 580 /* 581 * Go from start to hint, *inclusively* 582 */ 583 last = cur->next; 584 cur = map->header.next; 585 } 586 587 /* 588 * Search linearly 589 */ 590 591 while (cur != last) { 592 if (cur->end > address) { 593 if (address >= cur->start) { 594 /* 595 * Save this lookup for future hints, and 596 * return 597 */ 598 599 *entry = cur; 600 SAVE_HINT(map, cur); 601 return (TRUE); 602 } 603 break; 604 } 605 cur = cur->next; 606 } 607 *entry = cur->prev; 608 SAVE_HINT(map, *entry); 609 return (FALSE); 610 } 611 612 /* 613 * vm_map_insert: 614 * 615 * Inserts the given whole VM object into the target 616 * map at the specified address range. The object's 617 * size should match that of the address range. 618 * 619 * Requires that the map be locked, and leaves it so. Requires that 620 * sufficient vm_map_entry structures have been reserved and tracks 621 * the use via countp. 622 * 623 * If object is non-NULL, ref count must be bumped by caller 624 * prior to making call to account for the new entry. 625 */ 626 int 627 vm_map_insert(vm_map_t map, int *countp, 628 vm_object_t object, vm_ooffset_t offset, 629 vm_offset_t start, vm_offset_t end, vm_prot_t prot, vm_prot_t max, 630 int cow) 631 { 632 vm_map_entry_t new_entry; 633 vm_map_entry_t prev_entry; 634 vm_map_entry_t temp_entry; 635 vm_eflags_t protoeflags; 636 637 /* 638 * Check that the start and end points are not bogus. 639 */ 640 641 if ((start < map->min_offset) || (end > map->max_offset) || 642 (start >= end)) 643 return (KERN_INVALID_ADDRESS); 644 645 /* 646 * Find the entry prior to the proposed starting address; if it's part 647 * of an existing entry, this range is bogus. 648 */ 649 650 if (vm_map_lookup_entry(map, start, &temp_entry)) 651 return (KERN_NO_SPACE); 652 653 prev_entry = temp_entry; 654 655 /* 656 * Assert that the next entry doesn't overlap the end point. 657 */ 658 659 if ((prev_entry->next != &map->header) && 660 (prev_entry->next->start < end)) 661 return (KERN_NO_SPACE); 662 663 protoeflags = 0; 664 665 if (cow & MAP_COPY_ON_WRITE) 666 protoeflags |= MAP_ENTRY_COW|MAP_ENTRY_NEEDS_COPY; 667 668 if (cow & MAP_NOFAULT) { 669 protoeflags |= MAP_ENTRY_NOFAULT; 670 671 KASSERT(object == NULL, 672 ("vm_map_insert: paradoxical MAP_NOFAULT request")); 673 } 674 if (cow & MAP_DISABLE_SYNCER) 675 protoeflags |= MAP_ENTRY_NOSYNC; 676 if (cow & MAP_DISABLE_COREDUMP) 677 protoeflags |= MAP_ENTRY_NOCOREDUMP; 678 679 if (object) { 680 /* 681 * When object is non-NULL, it could be shared with another 682 * process. We have to set or clear OBJ_ONEMAPPING 683 * appropriately. 684 */ 685 if ((object->ref_count > 1) || (object->shadow_count != 0)) { 686 vm_object_clear_flag(object, OBJ_ONEMAPPING); 687 } 688 } 689 else if ((prev_entry != &map->header) && 690 (prev_entry->eflags == protoeflags) && 691 (prev_entry->end == start) && 692 (prev_entry->wired_count == 0) && 693 ((prev_entry->object.vm_object == NULL) || 694 vm_object_coalesce(prev_entry->object.vm_object, 695 OFF_TO_IDX(prev_entry->offset), 696 (vm_size_t)(prev_entry->end - prev_entry->start), 697 (vm_size_t)(end - prev_entry->end)))) { 698 /* 699 * We were able to extend the object. Determine if we 700 * can extend the previous map entry to include the 701 * new range as well. 702 */ 703 if ((prev_entry->inheritance == VM_INHERIT_DEFAULT) && 704 (prev_entry->protection == prot) && 705 (prev_entry->max_protection == max)) { 706 map->size += (end - prev_entry->end); 707 prev_entry->end = end; 708 vm_map_simplify_entry(map, prev_entry, countp); 709 return (KERN_SUCCESS); 710 } 711 712 /* 713 * If we can extend the object but cannot extend the 714 * map entry, we have to create a new map entry. We 715 * must bump the ref count on the extended object to 716 * account for it. object may be NULL. 717 */ 718 object = prev_entry->object.vm_object; 719 offset = prev_entry->offset + 720 (prev_entry->end - prev_entry->start); 721 vm_object_reference(object); 722 } 723 724 /* 725 * NOTE: if conditionals fail, object can be NULL here. This occurs 726 * in things like the buffer map where we manage kva but do not manage 727 * backing objects. 728 */ 729 730 /* 731 * Create a new entry 732 */ 733 734 new_entry = vm_map_entry_create(map, countp); 735 new_entry->start = start; 736 new_entry->end = end; 737 738 new_entry->eflags = protoeflags; 739 new_entry->object.vm_object = object; 740 new_entry->offset = offset; 741 new_entry->avail_ssize = 0; 742 743 new_entry->inheritance = VM_INHERIT_DEFAULT; 744 new_entry->protection = prot; 745 new_entry->max_protection = max; 746 new_entry->wired_count = 0; 747 748 /* 749 * Insert the new entry into the list 750 */ 751 752 vm_map_entry_link(map, prev_entry, new_entry); 753 map->size += new_entry->end - new_entry->start; 754 755 /* 756 * Update the free space hint 757 */ 758 if ((map->first_free == prev_entry) && 759 (prev_entry->end >= new_entry->start)) { 760 map->first_free = new_entry; 761 } 762 763 #if 0 764 /* 765 * Temporarily removed to avoid MAP_STACK panic, due to 766 * MAP_STACK being a huge hack. Will be added back in 767 * when MAP_STACK (and the user stack mapping) is fixed. 768 */ 769 /* 770 * It may be possible to simplify the entry 771 */ 772 vm_map_simplify_entry(map, new_entry, countp); 773 #endif 774 775 if (cow & (MAP_PREFAULT|MAP_PREFAULT_PARTIAL)) { 776 pmap_object_init_pt(map->pmap, start, prot, 777 object, OFF_TO_IDX(offset), end - start, 778 cow & MAP_PREFAULT_PARTIAL); 779 } 780 781 return (KERN_SUCCESS); 782 } 783 784 /* 785 * Find sufficient space for `length' bytes in the given map, starting at 786 * `start'. The map must be locked. Returns 0 on success, 1 on no space. 787 * 788 * This function will returned an arbitrarily aligned pointer. If no 789 * particular alignment is required you should pass align as 1. Note that 790 * the map may return PAGE_SIZE aligned pointers if all the lengths used in 791 * the map are a multiple of PAGE_SIZE, even if you pass a smaller align 792 * argument. 793 * 794 * 'align' should be a power of 2 but is not required to be. 795 */ 796 int 797 vm_map_findspace( 798 vm_map_t map, 799 vm_offset_t start, 800 vm_size_t length, 801 vm_offset_t align, 802 vm_offset_t *addr) 803 { 804 vm_map_entry_t entry, next; 805 vm_offset_t end; 806 vm_offset_t align_mask; 807 808 if (start < map->min_offset) 809 start = map->min_offset; 810 if (start > map->max_offset) 811 return (1); 812 813 /* 814 * If the alignment is not a power of 2 we will have to use 815 * a mod/division, set align_mask to a special value. 816 */ 817 if ((align | (align - 1)) + 1 != (align << 1)) 818 align_mask = (vm_offset_t)-1; 819 else 820 align_mask = align - 1; 821 822 retry: 823 /* 824 * Look for the first possible address; if there's already something 825 * at this address, we have to start after it. 826 */ 827 if (start == map->min_offset) { 828 if ((entry = map->first_free) != &map->header) 829 start = entry->end; 830 } else { 831 vm_map_entry_t tmp; 832 833 if (vm_map_lookup_entry(map, start, &tmp)) 834 start = tmp->end; 835 entry = tmp; 836 } 837 838 /* 839 * Look through the rest of the map, trying to fit a new region in the 840 * gap between existing regions, or after the very last region. 841 */ 842 for (;; start = (entry = next)->end) { 843 /* 844 * Adjust the proposed start by the requested alignment, 845 * be sure that we didn't wrap the address. 846 */ 847 if (align_mask == (vm_offset_t)-1) 848 end = ((start + align - 1) / align) * align; 849 else 850 end = (start + align_mask) & ~align_mask; 851 if (end < start) 852 return (1); 853 start = end; 854 /* 855 * Find the end of the proposed new region. Be sure we didn't 856 * go beyond the end of the map, or wrap around the address. 857 * Then check to see if this is the last entry or if the 858 * proposed end fits in the gap between this and the next 859 * entry. 860 */ 861 end = start + length; 862 if (end > map->max_offset || end < start) 863 return (1); 864 next = entry->next; 865 if (next == &map->header || next->start >= end) 866 break; 867 } 868 SAVE_HINT(map, entry); 869 if (map == kernel_map) { 870 vm_offset_t ksize; 871 if ((ksize = round_page(start + length)) > kernel_vm_end) { 872 pmap_growkernel(ksize); 873 goto retry; 874 } 875 } 876 *addr = start; 877 return (0); 878 } 879 880 /* 881 * vm_map_find finds an unallocated region in the target address 882 * map with the given length. The search is defined to be 883 * first-fit from the specified address; the region found is 884 * returned in the same parameter. 885 * 886 * If object is non-NULL, ref count must be bumped by caller 887 * prior to making call to account for the new entry. 888 */ 889 int 890 vm_map_find(vm_map_t map, vm_object_t object, vm_ooffset_t offset, 891 vm_offset_t *addr, /* IN/OUT */ 892 vm_size_t length, boolean_t find_space, vm_prot_t prot, 893 vm_prot_t max, int cow) 894 { 895 vm_offset_t start; 896 int result; 897 int count; 898 899 start = *addr; 900 901 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 902 vm_map_lock(map); 903 if (find_space) { 904 if (vm_map_findspace(map, start, length, 1, addr)) { 905 vm_map_unlock(map); 906 vm_map_entry_release(count); 907 return (KERN_NO_SPACE); 908 } 909 start = *addr; 910 } 911 result = vm_map_insert(map, &count, object, offset, 912 start, start + length, prot, max, cow); 913 vm_map_unlock(map); 914 vm_map_entry_release(count); 915 916 return (result); 917 } 918 919 /* 920 * vm_map_simplify_entry: 921 * 922 * Simplify the given map entry by merging with either neighbor. This 923 * routine also has the ability to merge with both neighbors. 924 * 925 * The map must be locked. 926 * 927 * This routine guarentees that the passed entry remains valid (though 928 * possibly extended). When merging, this routine may delete one or 929 * both neighbors. No action is taken on entries which have their 930 * in-transition flag set. 931 */ 932 void 933 vm_map_simplify_entry(vm_map_t map, vm_map_entry_t entry, int *countp) 934 { 935 vm_map_entry_t next, prev; 936 vm_size_t prevsize, esize; 937 938 if (entry->eflags & (MAP_ENTRY_IN_TRANSITION | MAP_ENTRY_IS_SUB_MAP)) { 939 ++mycpu->gd_cnt.v_intrans_coll; 940 return; 941 } 942 943 prev = entry->prev; 944 if (prev != &map->header) { 945 prevsize = prev->end - prev->start; 946 if ( (prev->end == entry->start) && 947 (prev->object.vm_object == entry->object.vm_object) && 948 (!prev->object.vm_object || 949 (prev->offset + prevsize == entry->offset)) && 950 (prev->eflags == entry->eflags) && 951 (prev->protection == entry->protection) && 952 (prev->max_protection == entry->max_protection) && 953 (prev->inheritance == entry->inheritance) && 954 (prev->wired_count == entry->wired_count)) { 955 if (map->first_free == prev) 956 map->first_free = entry; 957 if (map->hint == prev) 958 map->hint = entry; 959 vm_map_entry_unlink(map, prev); 960 entry->start = prev->start; 961 entry->offset = prev->offset; 962 if (prev->object.vm_object) 963 vm_object_deallocate(prev->object.vm_object); 964 vm_map_entry_dispose(map, prev, countp); 965 } 966 } 967 968 next = entry->next; 969 if (next != &map->header) { 970 esize = entry->end - entry->start; 971 if ((entry->end == next->start) && 972 (next->object.vm_object == entry->object.vm_object) && 973 (!entry->object.vm_object || 974 (entry->offset + esize == next->offset)) && 975 (next->eflags == entry->eflags) && 976 (next->protection == entry->protection) && 977 (next->max_protection == entry->max_protection) && 978 (next->inheritance == entry->inheritance) && 979 (next->wired_count == entry->wired_count)) { 980 if (map->first_free == next) 981 map->first_free = entry; 982 if (map->hint == next) 983 map->hint = entry; 984 vm_map_entry_unlink(map, next); 985 entry->end = next->end; 986 if (next->object.vm_object) 987 vm_object_deallocate(next->object.vm_object); 988 vm_map_entry_dispose(map, next, countp); 989 } 990 } 991 } 992 /* 993 * vm_map_clip_start: [ internal use only ] 994 * 995 * Asserts that the given entry begins at or after 996 * the specified address; if necessary, 997 * it splits the entry into two. 998 */ 999 #define vm_map_clip_start(map, entry, startaddr, countp) \ 1000 { \ 1001 if (startaddr > entry->start) \ 1002 _vm_map_clip_start(map, entry, startaddr, countp); \ 1003 } 1004 1005 /* 1006 * This routine is called only when it is known that 1007 * the entry must be split. 1008 */ 1009 static void 1010 _vm_map_clip_start(vm_map_t map, vm_map_entry_t entry, vm_offset_t start, int *countp) 1011 { 1012 vm_map_entry_t new_entry; 1013 1014 /* 1015 * Split off the front portion -- note that we must insert the new 1016 * entry BEFORE this one, so that this entry has the specified 1017 * starting address. 1018 */ 1019 1020 vm_map_simplify_entry(map, entry, countp); 1021 1022 /* 1023 * If there is no object backing this entry, we might as well create 1024 * one now. If we defer it, an object can get created after the map 1025 * is clipped, and individual objects will be created for the split-up 1026 * map. This is a bit of a hack, but is also about the best place to 1027 * put this improvement. 1028 */ 1029 1030 if (entry->object.vm_object == NULL && !map->system_map) { 1031 vm_object_t object; 1032 object = vm_object_allocate(OBJT_DEFAULT, 1033 atop(entry->end - entry->start)); 1034 entry->object.vm_object = object; 1035 entry->offset = 0; 1036 } 1037 1038 new_entry = vm_map_entry_create(map, countp); 1039 *new_entry = *entry; 1040 1041 new_entry->end = start; 1042 entry->offset += (start - entry->start); 1043 entry->start = start; 1044 1045 vm_map_entry_link(map, entry->prev, new_entry); 1046 1047 if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0) { 1048 vm_object_reference(new_entry->object.vm_object); 1049 } 1050 } 1051 1052 /* 1053 * vm_map_clip_end: [ internal use only ] 1054 * 1055 * Asserts that the given entry ends at or before 1056 * the specified address; if necessary, 1057 * it splits the entry into two. 1058 */ 1059 1060 #define vm_map_clip_end(map, entry, endaddr, countp) \ 1061 { \ 1062 if (endaddr < entry->end) \ 1063 _vm_map_clip_end(map, entry, endaddr, countp); \ 1064 } 1065 1066 /* 1067 * This routine is called only when it is known that 1068 * the entry must be split. 1069 */ 1070 static void 1071 _vm_map_clip_end(vm_map_t map, vm_map_entry_t entry, vm_offset_t end, int *countp) 1072 { 1073 vm_map_entry_t new_entry; 1074 1075 /* 1076 * If there is no object backing this entry, we might as well create 1077 * one now. If we defer it, an object can get created after the map 1078 * is clipped, and individual objects will be created for the split-up 1079 * map. This is a bit of a hack, but is also about the best place to 1080 * put this improvement. 1081 */ 1082 1083 if (entry->object.vm_object == NULL && !map->system_map) { 1084 vm_object_t object; 1085 object = vm_object_allocate(OBJT_DEFAULT, 1086 atop(entry->end - entry->start)); 1087 entry->object.vm_object = object; 1088 entry->offset = 0; 1089 } 1090 1091 /* 1092 * Create a new entry and insert it AFTER the specified entry 1093 */ 1094 1095 new_entry = vm_map_entry_create(map, countp); 1096 *new_entry = *entry; 1097 1098 new_entry->start = entry->end = end; 1099 new_entry->offset += (end - entry->start); 1100 1101 vm_map_entry_link(map, entry, new_entry); 1102 1103 if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0) { 1104 vm_object_reference(new_entry->object.vm_object); 1105 } 1106 } 1107 1108 /* 1109 * VM_MAP_RANGE_CHECK: [ internal use only ] 1110 * 1111 * Asserts that the starting and ending region 1112 * addresses fall within the valid range of the map. 1113 */ 1114 #define VM_MAP_RANGE_CHECK(map, start, end) \ 1115 { \ 1116 if (start < vm_map_min(map)) \ 1117 start = vm_map_min(map); \ 1118 if (end > vm_map_max(map)) \ 1119 end = vm_map_max(map); \ 1120 if (start > end) \ 1121 start = end; \ 1122 } 1123 1124 /* 1125 * vm_map_transition_wait: [ kernel use only ] 1126 * 1127 * Used to block when an in-transition collison occurs. The map 1128 * is unlocked for the sleep and relocked before the return. 1129 */ 1130 static 1131 void 1132 vm_map_transition_wait(vm_map_t map) 1133 { 1134 vm_map_unlock(map); 1135 tsleep(map, 0, "vment", 0); 1136 vm_map_lock(map); 1137 } 1138 1139 /* 1140 * CLIP_CHECK_BACK 1141 * CLIP_CHECK_FWD 1142 * 1143 * When we do blocking operations with the map lock held it is 1144 * possible that a clip might have occured on our in-transit entry, 1145 * requiring an adjustment to the entry in our loop. These macros 1146 * help the pageable and clip_range code deal with the case. The 1147 * conditional costs virtually nothing if no clipping has occured. 1148 */ 1149 1150 #define CLIP_CHECK_BACK(entry, save_start) \ 1151 do { \ 1152 while (entry->start != save_start) { \ 1153 entry = entry->prev; \ 1154 KASSERT(entry != &map->header, ("bad entry clip")); \ 1155 } \ 1156 } while(0) 1157 1158 #define CLIP_CHECK_FWD(entry, save_end) \ 1159 do { \ 1160 while (entry->end != save_end) { \ 1161 entry = entry->next; \ 1162 KASSERT(entry != &map->header, ("bad entry clip")); \ 1163 } \ 1164 } while(0) 1165 1166 1167 /* 1168 * vm_map_clip_range: [ kernel use only ] 1169 * 1170 * Clip the specified range and return the base entry. The 1171 * range may cover several entries starting at the returned base 1172 * and the first and last entry in the covering sequence will be 1173 * properly clipped to the requested start and end address. 1174 * 1175 * If no holes are allowed you should pass the MAP_CLIP_NO_HOLES 1176 * flag. 1177 * 1178 * The MAP_ENTRY_IN_TRANSITION flag will be set for the entries 1179 * covered by the requested range. 1180 * 1181 * The map must be exclusively locked on entry and will remain locked 1182 * on return. If no range exists or the range contains holes and you 1183 * specified that no holes were allowed, NULL will be returned. This 1184 * routine may temporarily unlock the map in order avoid a deadlock when 1185 * sleeping. 1186 */ 1187 static 1188 vm_map_entry_t 1189 vm_map_clip_range(vm_map_t map, vm_offset_t start, vm_offset_t end, 1190 int *countp, int flags) 1191 { 1192 vm_map_entry_t start_entry; 1193 vm_map_entry_t entry; 1194 1195 /* 1196 * Locate the entry and effect initial clipping. The in-transition 1197 * case does not occur very often so do not try to optimize it. 1198 */ 1199 again: 1200 if (vm_map_lookup_entry(map, start, &start_entry) == FALSE) 1201 return (NULL); 1202 entry = start_entry; 1203 if (entry->eflags & MAP_ENTRY_IN_TRANSITION) { 1204 entry->eflags |= MAP_ENTRY_NEEDS_WAKEUP; 1205 ++mycpu->gd_cnt.v_intrans_coll; 1206 ++mycpu->gd_cnt.v_intrans_wait; 1207 vm_map_transition_wait(map); 1208 /* 1209 * entry and/or start_entry may have been clipped while 1210 * we slept, or may have gone away entirely. We have 1211 * to restart from the lookup. 1212 */ 1213 goto again; 1214 } 1215 /* 1216 * Since we hold an exclusive map lock we do not have to restart 1217 * after clipping, even though clipping may block in zalloc. 1218 */ 1219 vm_map_clip_start(map, entry, start, countp); 1220 vm_map_clip_end(map, entry, end, countp); 1221 entry->eflags |= MAP_ENTRY_IN_TRANSITION; 1222 1223 /* 1224 * Scan entries covered by the range. When working on the next 1225 * entry a restart need only re-loop on the current entry which 1226 * we have already locked, since 'next' may have changed. Also, 1227 * even though entry is safe, it may have been clipped so we 1228 * have to iterate forwards through the clip after sleeping. 1229 */ 1230 while (entry->next != &map->header && entry->next->start < end) { 1231 vm_map_entry_t next = entry->next; 1232 1233 if (flags & MAP_CLIP_NO_HOLES) { 1234 if (next->start > entry->end) { 1235 vm_map_unclip_range(map, start_entry, 1236 start, entry->end, countp, flags); 1237 return(NULL); 1238 } 1239 } 1240 1241 if (next->eflags & MAP_ENTRY_IN_TRANSITION) { 1242 vm_offset_t save_end = entry->end; 1243 next->eflags |= MAP_ENTRY_NEEDS_WAKEUP; 1244 ++mycpu->gd_cnt.v_intrans_coll; 1245 ++mycpu->gd_cnt.v_intrans_wait; 1246 vm_map_transition_wait(map); 1247 1248 /* 1249 * clips might have occured while we blocked. 1250 */ 1251 CLIP_CHECK_FWD(entry, save_end); 1252 CLIP_CHECK_BACK(start_entry, start); 1253 continue; 1254 } 1255 /* 1256 * No restart necessary even though clip_end may block, we 1257 * are holding the map lock. 1258 */ 1259 vm_map_clip_end(map, next, end, countp); 1260 next->eflags |= MAP_ENTRY_IN_TRANSITION; 1261 entry = next; 1262 } 1263 if (flags & MAP_CLIP_NO_HOLES) { 1264 if (entry->end != end) { 1265 vm_map_unclip_range(map, start_entry, 1266 start, entry->end, countp, flags); 1267 return(NULL); 1268 } 1269 } 1270 return(start_entry); 1271 } 1272 1273 /* 1274 * vm_map_unclip_range: [ kernel use only ] 1275 * 1276 * Undo the effect of vm_map_clip_range(). You should pass the same 1277 * flags and the same range that you passed to vm_map_clip_range(). 1278 * This code will clear the in-transition flag on the entries and 1279 * wake up anyone waiting. This code will also simplify the sequence 1280 * and attempt to merge it with entries before and after the sequence. 1281 * 1282 * The map must be locked on entry and will remain locked on return. 1283 * 1284 * Note that you should also pass the start_entry returned by 1285 * vm_map_clip_range(). However, if you block between the two calls 1286 * with the map unlocked please be aware that the start_entry may 1287 * have been clipped and you may need to scan it backwards to find 1288 * the entry corresponding with the original start address. You are 1289 * responsible for this, vm_map_unclip_range() expects the correct 1290 * start_entry to be passed to it and will KASSERT otherwise. 1291 */ 1292 static 1293 void 1294 vm_map_unclip_range( 1295 vm_map_t map, 1296 vm_map_entry_t start_entry, 1297 vm_offset_t start, 1298 vm_offset_t end, 1299 int *countp, 1300 int flags) 1301 { 1302 vm_map_entry_t entry; 1303 1304 entry = start_entry; 1305 1306 KASSERT(entry->start == start, ("unclip_range: illegal base entry")); 1307 while (entry != &map->header && entry->start < end) { 1308 KASSERT(entry->eflags & MAP_ENTRY_IN_TRANSITION, ("in-transition flag not set during unclip on: %p", entry)); 1309 KASSERT(entry->end <= end, ("unclip_range: tail wasn't clipped")); 1310 entry->eflags &= ~MAP_ENTRY_IN_TRANSITION; 1311 if (entry->eflags & MAP_ENTRY_NEEDS_WAKEUP) { 1312 entry->eflags &= ~MAP_ENTRY_NEEDS_WAKEUP; 1313 wakeup(map); 1314 } 1315 entry = entry->next; 1316 } 1317 1318 /* 1319 * Simplification does not block so there is no restart case. 1320 */ 1321 entry = start_entry; 1322 while (entry != &map->header && entry->start < end) { 1323 vm_map_simplify_entry(map, entry, countp); 1324 entry = entry->next; 1325 } 1326 } 1327 1328 /* 1329 * vm_map_submap: [ kernel use only ] 1330 * 1331 * Mark the given range as handled by a subordinate map. 1332 * 1333 * This range must have been created with vm_map_find, 1334 * and no other operations may have been performed on this 1335 * range prior to calling vm_map_submap. 1336 * 1337 * Only a limited number of operations can be performed 1338 * within this rage after calling vm_map_submap: 1339 * vm_fault 1340 * [Don't try vm_map_copy!] 1341 * 1342 * To remove a submapping, one must first remove the 1343 * range from the superior map, and then destroy the 1344 * submap (if desired). [Better yet, don't try it.] 1345 */ 1346 int 1347 vm_map_submap(vm_map_t map, vm_offset_t start, vm_offset_t end, vm_map_t submap) 1348 { 1349 vm_map_entry_t entry; 1350 int result = KERN_INVALID_ARGUMENT; 1351 int count; 1352 1353 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 1354 vm_map_lock(map); 1355 1356 VM_MAP_RANGE_CHECK(map, start, end); 1357 1358 if (vm_map_lookup_entry(map, start, &entry)) { 1359 vm_map_clip_start(map, entry, start, &count); 1360 } else { 1361 entry = entry->next; 1362 } 1363 1364 vm_map_clip_end(map, entry, end, &count); 1365 1366 if ((entry->start == start) && (entry->end == end) && 1367 ((entry->eflags & MAP_ENTRY_COW) == 0) && 1368 (entry->object.vm_object == NULL)) { 1369 entry->object.sub_map = submap; 1370 entry->eflags |= MAP_ENTRY_IS_SUB_MAP; 1371 result = KERN_SUCCESS; 1372 } 1373 vm_map_unlock(map); 1374 vm_map_entry_release(count); 1375 1376 return (result); 1377 } 1378 1379 /* 1380 * vm_map_protect: 1381 * 1382 * Sets the protection of the specified address 1383 * region in the target map. If "set_max" is 1384 * specified, the maximum protection is to be set; 1385 * otherwise, only the current protection is affected. 1386 */ 1387 int 1388 vm_map_protect(vm_map_t map, vm_offset_t start, vm_offset_t end, 1389 vm_prot_t new_prot, boolean_t set_max) 1390 { 1391 vm_map_entry_t current; 1392 vm_map_entry_t entry; 1393 int count; 1394 1395 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 1396 vm_map_lock(map); 1397 1398 VM_MAP_RANGE_CHECK(map, start, end); 1399 1400 if (vm_map_lookup_entry(map, start, &entry)) { 1401 vm_map_clip_start(map, entry, start, &count); 1402 } else { 1403 entry = entry->next; 1404 } 1405 1406 /* 1407 * Make a first pass to check for protection violations. 1408 */ 1409 1410 current = entry; 1411 while ((current != &map->header) && (current->start < end)) { 1412 if (current->eflags & MAP_ENTRY_IS_SUB_MAP) { 1413 vm_map_unlock(map); 1414 vm_map_entry_release(count); 1415 return (KERN_INVALID_ARGUMENT); 1416 } 1417 if ((new_prot & current->max_protection) != new_prot) { 1418 vm_map_unlock(map); 1419 vm_map_entry_release(count); 1420 return (KERN_PROTECTION_FAILURE); 1421 } 1422 current = current->next; 1423 } 1424 1425 /* 1426 * Go back and fix up protections. [Note that clipping is not 1427 * necessary the second time.] 1428 */ 1429 current = entry; 1430 1431 while ((current != &map->header) && (current->start < end)) { 1432 vm_prot_t old_prot; 1433 1434 vm_map_clip_end(map, current, end, &count); 1435 1436 old_prot = current->protection; 1437 if (set_max) 1438 current->protection = 1439 (current->max_protection = new_prot) & 1440 old_prot; 1441 else 1442 current->protection = new_prot; 1443 1444 /* 1445 * Update physical map if necessary. Worry about copy-on-write 1446 * here -- CHECK THIS XXX 1447 */ 1448 1449 if (current->protection != old_prot) { 1450 #define MASK(entry) (((entry)->eflags & MAP_ENTRY_COW) ? ~VM_PROT_WRITE : \ 1451 VM_PROT_ALL) 1452 1453 pmap_protect(map->pmap, current->start, 1454 current->end, 1455 current->protection & MASK(current)); 1456 #undef MASK 1457 } 1458 1459 vm_map_simplify_entry(map, current, &count); 1460 1461 current = current->next; 1462 } 1463 1464 vm_map_unlock(map); 1465 vm_map_entry_release(count); 1466 return (KERN_SUCCESS); 1467 } 1468 1469 /* 1470 * vm_map_madvise: 1471 * 1472 * This routine traverses a processes map handling the madvise 1473 * system call. Advisories are classified as either those effecting 1474 * the vm_map_entry structure, or those effecting the underlying 1475 * objects. 1476 */ 1477 1478 int 1479 vm_map_madvise(vm_map_t map, vm_offset_t start, vm_offset_t end, int behav) 1480 { 1481 vm_map_entry_t current, entry; 1482 int modify_map = 0; 1483 int count; 1484 1485 /* 1486 * Some madvise calls directly modify the vm_map_entry, in which case 1487 * we need to use an exclusive lock on the map and we need to perform 1488 * various clipping operations. Otherwise we only need a read-lock 1489 * on the map. 1490 */ 1491 1492 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 1493 1494 switch(behav) { 1495 case MADV_NORMAL: 1496 case MADV_SEQUENTIAL: 1497 case MADV_RANDOM: 1498 case MADV_NOSYNC: 1499 case MADV_AUTOSYNC: 1500 case MADV_NOCORE: 1501 case MADV_CORE: 1502 modify_map = 1; 1503 vm_map_lock(map); 1504 break; 1505 case MADV_WILLNEED: 1506 case MADV_DONTNEED: 1507 case MADV_FREE: 1508 vm_map_lock_read(map); 1509 break; 1510 default: 1511 vm_map_entry_release(count); 1512 return (KERN_INVALID_ARGUMENT); 1513 } 1514 1515 /* 1516 * Locate starting entry and clip if necessary. 1517 */ 1518 1519 VM_MAP_RANGE_CHECK(map, start, end); 1520 1521 if (vm_map_lookup_entry(map, start, &entry)) { 1522 if (modify_map) 1523 vm_map_clip_start(map, entry, start, &count); 1524 } else { 1525 entry = entry->next; 1526 } 1527 1528 if (modify_map) { 1529 /* 1530 * madvise behaviors that are implemented in the vm_map_entry. 1531 * 1532 * We clip the vm_map_entry so that behavioral changes are 1533 * limited to the specified address range. 1534 */ 1535 for (current = entry; 1536 (current != &map->header) && (current->start < end); 1537 current = current->next 1538 ) { 1539 if (current->eflags & MAP_ENTRY_IS_SUB_MAP) 1540 continue; 1541 1542 vm_map_clip_end(map, current, end, &count); 1543 1544 switch (behav) { 1545 case MADV_NORMAL: 1546 vm_map_entry_set_behavior(current, MAP_ENTRY_BEHAV_NORMAL); 1547 break; 1548 case MADV_SEQUENTIAL: 1549 vm_map_entry_set_behavior(current, MAP_ENTRY_BEHAV_SEQUENTIAL); 1550 break; 1551 case MADV_RANDOM: 1552 vm_map_entry_set_behavior(current, MAP_ENTRY_BEHAV_RANDOM); 1553 break; 1554 case MADV_NOSYNC: 1555 current->eflags |= MAP_ENTRY_NOSYNC; 1556 break; 1557 case MADV_AUTOSYNC: 1558 current->eflags &= ~MAP_ENTRY_NOSYNC; 1559 break; 1560 case MADV_NOCORE: 1561 current->eflags |= MAP_ENTRY_NOCOREDUMP; 1562 break; 1563 case MADV_CORE: 1564 current->eflags &= ~MAP_ENTRY_NOCOREDUMP; 1565 break; 1566 default: 1567 break; 1568 } 1569 vm_map_simplify_entry(map, current, &count); 1570 } 1571 vm_map_unlock(map); 1572 } else { 1573 vm_pindex_t pindex; 1574 int count; 1575 1576 /* 1577 * madvise behaviors that are implemented in the underlying 1578 * vm_object. 1579 * 1580 * Since we don't clip the vm_map_entry, we have to clip 1581 * the vm_object pindex and count. 1582 */ 1583 for (current = entry; 1584 (current != &map->header) && (current->start < end); 1585 current = current->next 1586 ) { 1587 vm_offset_t useStart; 1588 1589 if (current->eflags & MAP_ENTRY_IS_SUB_MAP) 1590 continue; 1591 1592 pindex = OFF_TO_IDX(current->offset); 1593 count = atop(current->end - current->start); 1594 useStart = current->start; 1595 1596 if (current->start < start) { 1597 pindex += atop(start - current->start); 1598 count -= atop(start - current->start); 1599 useStart = start; 1600 } 1601 if (current->end > end) 1602 count -= atop(current->end - end); 1603 1604 if (count <= 0) 1605 continue; 1606 1607 vm_object_madvise(current->object.vm_object, 1608 pindex, count, behav); 1609 if (behav == MADV_WILLNEED) { 1610 pmap_object_init_pt( 1611 map->pmap, 1612 useStart, 1613 current->protection, 1614 current->object.vm_object, 1615 pindex, 1616 (count << PAGE_SHIFT), 1617 MAP_PREFAULT_MADVISE 1618 ); 1619 } 1620 } 1621 vm_map_unlock_read(map); 1622 } 1623 vm_map_entry_release(count); 1624 return(0); 1625 } 1626 1627 1628 /* 1629 * vm_map_inherit: 1630 * 1631 * Sets the inheritance of the specified address 1632 * range in the target map. Inheritance 1633 * affects how the map will be shared with 1634 * child maps at the time of vm_map_fork. 1635 */ 1636 int 1637 vm_map_inherit(vm_map_t map, vm_offset_t start, vm_offset_t end, 1638 vm_inherit_t new_inheritance) 1639 { 1640 vm_map_entry_t entry; 1641 vm_map_entry_t temp_entry; 1642 int count; 1643 1644 switch (new_inheritance) { 1645 case VM_INHERIT_NONE: 1646 case VM_INHERIT_COPY: 1647 case VM_INHERIT_SHARE: 1648 break; 1649 default: 1650 return (KERN_INVALID_ARGUMENT); 1651 } 1652 1653 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 1654 vm_map_lock(map); 1655 1656 VM_MAP_RANGE_CHECK(map, start, end); 1657 1658 if (vm_map_lookup_entry(map, start, &temp_entry)) { 1659 entry = temp_entry; 1660 vm_map_clip_start(map, entry, start, &count); 1661 } else 1662 entry = temp_entry->next; 1663 1664 while ((entry != &map->header) && (entry->start < end)) { 1665 vm_map_clip_end(map, entry, end, &count); 1666 1667 entry->inheritance = new_inheritance; 1668 1669 vm_map_simplify_entry(map, entry, &count); 1670 1671 entry = entry->next; 1672 } 1673 vm_map_unlock(map); 1674 vm_map_entry_release(count); 1675 return (KERN_SUCCESS); 1676 } 1677 1678 /* 1679 * Implement the semantics of mlock 1680 */ 1681 int 1682 vm_map_unwire(vm_map_t map, vm_offset_t start, vm_offset_t real_end, 1683 boolean_t new_pageable) 1684 { 1685 vm_map_entry_t entry; 1686 vm_map_entry_t start_entry; 1687 vm_offset_t end; 1688 int rv = KERN_SUCCESS; 1689 int count; 1690 1691 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 1692 vm_map_lock(map); 1693 VM_MAP_RANGE_CHECK(map, start, real_end); 1694 end = real_end; 1695 1696 start_entry = vm_map_clip_range(map, start, end, &count, MAP_CLIP_NO_HOLES); 1697 if (start_entry == NULL) { 1698 vm_map_unlock(map); 1699 vm_map_entry_release(count); 1700 return (KERN_INVALID_ADDRESS); 1701 } 1702 1703 if (new_pageable == 0) { 1704 entry = start_entry; 1705 while ((entry != &map->header) && (entry->start < end)) { 1706 vm_offset_t save_start; 1707 vm_offset_t save_end; 1708 1709 /* 1710 * Already user wired or hard wired (trivial cases) 1711 */ 1712 if (entry->eflags & MAP_ENTRY_USER_WIRED) { 1713 entry = entry->next; 1714 continue; 1715 } 1716 if (entry->wired_count != 0) { 1717 entry->wired_count++; 1718 entry->eflags |= MAP_ENTRY_USER_WIRED; 1719 entry = entry->next; 1720 continue; 1721 } 1722 1723 /* 1724 * A new wiring requires instantiation of appropriate 1725 * management structures and the faulting in of the 1726 * page. 1727 */ 1728 if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0) { 1729 int copyflag = entry->eflags & MAP_ENTRY_NEEDS_COPY; 1730 if (copyflag && ((entry->protection & VM_PROT_WRITE) != 0)) { 1731 1732 vm_object_shadow(&entry->object.vm_object, 1733 &entry->offset, 1734 atop(entry->end - entry->start)); 1735 entry->eflags &= ~MAP_ENTRY_NEEDS_COPY; 1736 1737 } else if (entry->object.vm_object == NULL && 1738 !map->system_map) { 1739 1740 entry->object.vm_object = 1741 vm_object_allocate(OBJT_DEFAULT, 1742 atop(entry->end - entry->start)); 1743 entry->offset = (vm_offset_t) 0; 1744 1745 } 1746 } 1747 entry->wired_count++; 1748 entry->eflags |= MAP_ENTRY_USER_WIRED; 1749 1750 /* 1751 * Now fault in the area. The map lock needs to be 1752 * manipulated to avoid deadlocks. The in-transition 1753 * flag protects the entries. 1754 */ 1755 save_start = entry->start; 1756 save_end = entry->end; 1757 vm_map_unlock(map); 1758 map->timestamp++; 1759 rv = vm_fault_user_wire(map, save_start, save_end); 1760 vm_map_lock(map); 1761 if (rv) { 1762 CLIP_CHECK_BACK(entry, save_start); 1763 for (;;) { 1764 KASSERT(entry->wired_count == 1, ("bad wired_count on entry")); 1765 entry->eflags &= ~MAP_ENTRY_USER_WIRED; 1766 entry->wired_count = 0; 1767 if (entry->end == save_end) 1768 break; 1769 entry = entry->next; 1770 KASSERT(entry != &map->header, ("bad entry clip during backout")); 1771 } 1772 end = save_start; /* unwire the rest */ 1773 break; 1774 } 1775 /* 1776 * note that even though the entry might have been 1777 * clipped, the USER_WIRED flag we set prevents 1778 * duplication so we do not have to do a 1779 * clip check. 1780 */ 1781 entry = entry->next; 1782 } 1783 1784 /* 1785 * If we failed fall through to the unwiring section to 1786 * unwire what we had wired so far. 'end' has already 1787 * been adjusted. 1788 */ 1789 if (rv) 1790 new_pageable = 1; 1791 1792 /* 1793 * start_entry might have been clipped if we unlocked the 1794 * map and blocked. No matter how clipped it has gotten 1795 * there should be a fragment that is on our start boundary. 1796 */ 1797 CLIP_CHECK_BACK(start_entry, start); 1798 } 1799 1800 /* 1801 * Deal with the unwiring case. 1802 */ 1803 if (new_pageable) { 1804 /* 1805 * This is the unwiring case. We must first ensure that the 1806 * range to be unwired is really wired down. We know there 1807 * are no holes. 1808 */ 1809 entry = start_entry; 1810 while ((entry != &map->header) && (entry->start < end)) { 1811 if ((entry->eflags & MAP_ENTRY_USER_WIRED) == 0) { 1812 rv = KERN_INVALID_ARGUMENT; 1813 goto done; 1814 } 1815 KASSERT(entry->wired_count != 0, ("wired count was 0 with USER_WIRED set! %p", entry)); 1816 entry = entry->next; 1817 } 1818 1819 /* 1820 * Now decrement the wiring count for each region. If a region 1821 * becomes completely unwired, unwire its physical pages and 1822 * mappings. 1823 */ 1824 /* 1825 * The map entries are processed in a loop, checking to 1826 * make sure the entry is wired and asserting it has a wired 1827 * count. However, another loop was inserted more-or-less in 1828 * the middle of the unwiring path. This loop picks up the 1829 * "entry" loop variable from the first loop without first 1830 * setting it to start_entry. Naturally, the secound loop 1831 * is never entered and the pages backing the entries are 1832 * never unwired. This can lead to a leak of wired pages. 1833 */ 1834 entry = start_entry; 1835 while ((entry != &map->header) && (entry->start < end)) { 1836 KASSERT(entry->eflags & MAP_ENTRY_USER_WIRED, ("expected USER_WIRED on entry %p", entry)); 1837 entry->eflags &= ~MAP_ENTRY_USER_WIRED; 1838 entry->wired_count--; 1839 if (entry->wired_count == 0) 1840 vm_fault_unwire(map, entry->start, entry->end); 1841 entry = entry->next; 1842 } 1843 } 1844 done: 1845 vm_map_unclip_range(map, start_entry, start, real_end, &count, 1846 MAP_CLIP_NO_HOLES); 1847 map->timestamp++; 1848 vm_map_unlock(map); 1849 vm_map_entry_release(count); 1850 return (rv); 1851 } 1852 1853 /* 1854 * vm_map_wire: 1855 * 1856 * Sets the pageability of the specified address 1857 * range in the target map. Regions specified 1858 * as not pageable require locked-down physical 1859 * memory and physical page maps. 1860 * 1861 * The map must not be locked, but a reference 1862 * must remain to the map throughout the call. 1863 * 1864 * This function may be called via the zalloc path and must properly 1865 * reserve map entries for kernel_map. 1866 */ 1867 int 1868 vm_map_wire(vm_map_t map, vm_offset_t start, vm_offset_t real_end, int kmflags) 1869 { 1870 vm_map_entry_t entry; 1871 vm_map_entry_t start_entry; 1872 vm_offset_t end; 1873 int rv = KERN_SUCCESS; 1874 int count; 1875 int s; 1876 1877 if (kmflags & KM_KRESERVE) 1878 count = vm_map_entry_kreserve(MAP_RESERVE_COUNT); 1879 else 1880 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 1881 vm_map_lock(map); 1882 VM_MAP_RANGE_CHECK(map, start, real_end); 1883 end = real_end; 1884 1885 start_entry = vm_map_clip_range(map, start, end, &count, MAP_CLIP_NO_HOLES); 1886 if (start_entry == NULL) { 1887 vm_map_unlock(map); 1888 rv = KERN_INVALID_ADDRESS; 1889 goto failure; 1890 } 1891 if ((kmflags & KM_PAGEABLE) == 0) { 1892 /* 1893 * Wiring. 1894 * 1895 * 1. Holding the write lock, we create any shadow or zero-fill 1896 * objects that need to be created. Then we clip each map 1897 * entry to the region to be wired and increment its wiring 1898 * count. We create objects before clipping the map entries 1899 * to avoid object proliferation. 1900 * 1901 * 2. We downgrade to a read lock, and call vm_fault_wire to 1902 * fault in the pages for any newly wired area (wired_count is 1903 * 1). 1904 * 1905 * Downgrading to a read lock for vm_fault_wire avoids a 1906 * possible deadlock with another process that may have faulted 1907 * on one of the pages to be wired (it would mark the page busy, 1908 * blocking us, then in turn block on the map lock that we 1909 * hold). Because of problems in the recursive lock package, 1910 * we cannot upgrade to a write lock in vm_map_lookup. Thus, 1911 * any actions that require the write lock must be done 1912 * beforehand. Because we keep the read lock on the map, the 1913 * copy-on-write status of the entries we modify here cannot 1914 * change. 1915 */ 1916 1917 entry = start_entry; 1918 while ((entry != &map->header) && (entry->start < end)) { 1919 /* 1920 * Trivial case if the entry is already wired 1921 */ 1922 if (entry->wired_count) { 1923 entry->wired_count++; 1924 entry = entry->next; 1925 continue; 1926 } 1927 1928 /* 1929 * The entry is being newly wired, we have to setup 1930 * appropriate management structures. A shadow 1931 * object is required for a copy-on-write region, 1932 * or a normal object for a zero-fill region. We 1933 * do not have to do this for entries that point to sub 1934 * maps because we won't hold the lock on the sub map. 1935 */ 1936 if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0) { 1937 int copyflag = entry->eflags & MAP_ENTRY_NEEDS_COPY; 1938 if (copyflag && 1939 ((entry->protection & VM_PROT_WRITE) != 0)) { 1940 1941 vm_object_shadow(&entry->object.vm_object, 1942 &entry->offset, 1943 atop(entry->end - entry->start)); 1944 entry->eflags &= ~MAP_ENTRY_NEEDS_COPY; 1945 } else if (entry->object.vm_object == NULL && 1946 !map->system_map) { 1947 entry->object.vm_object = 1948 vm_object_allocate(OBJT_DEFAULT, 1949 atop(entry->end - entry->start)); 1950 entry->offset = (vm_offset_t) 0; 1951 } 1952 } 1953 1954 entry->wired_count++; 1955 entry = entry->next; 1956 } 1957 1958 /* 1959 * Pass 2. 1960 */ 1961 1962 /* 1963 * HACK HACK HACK HACK 1964 * 1965 * Unlock the map to avoid deadlocks. The in-transit flag 1966 * protects us from most changes but note that 1967 * clipping may still occur. To prevent clipping from 1968 * occuring after the unlock, except for when we are 1969 * blocking in vm_fault_wire, we must run at splvm(). 1970 * Otherwise our accesses to entry->start and entry->end 1971 * could be corrupted. We have to set splvm() prior to 1972 * unlocking so start_entry does not change out from 1973 * under us at the very beginning of the loop. 1974 * 1975 * HACK HACK HACK HACK 1976 */ 1977 1978 s = splvm(); 1979 vm_map_unlock(map); 1980 1981 entry = start_entry; 1982 while (entry != &map->header && entry->start < end) { 1983 /* 1984 * If vm_fault_wire fails for any page we need to undo 1985 * what has been done. We decrement the wiring count 1986 * for those pages which have not yet been wired (now) 1987 * and unwire those that have (later). 1988 */ 1989 vm_offset_t save_start = entry->start; 1990 vm_offset_t save_end = entry->end; 1991 1992 if (entry->wired_count == 1) 1993 rv = vm_fault_wire(map, entry->start, entry->end); 1994 if (rv) { 1995 CLIP_CHECK_BACK(entry, save_start); 1996 for (;;) { 1997 KASSERT(entry->wired_count == 1, ("wired_count changed unexpectedly")); 1998 entry->wired_count = 0; 1999 if (entry->end == save_end) 2000 break; 2001 entry = entry->next; 2002 KASSERT(entry != &map->header, ("bad entry clip during backout")); 2003 } 2004 end = save_start; 2005 break; 2006 } 2007 CLIP_CHECK_FWD(entry, save_end); 2008 entry = entry->next; 2009 } 2010 splx(s); 2011 2012 /* 2013 * relock. start_entry is still IN_TRANSITION and must 2014 * still exist, but may have been clipped (handled just 2015 * below). 2016 */ 2017 vm_map_lock(map); 2018 2019 /* 2020 * If a failure occured undo everything by falling through 2021 * to the unwiring code. 'end' has already been adjusted 2022 * appropriately. 2023 */ 2024 if (rv) 2025 kmflags |= KM_PAGEABLE; 2026 2027 /* 2028 * start_entry might have been clipped if we unlocked the 2029 * map and blocked. No matter how clipped it has gotten 2030 * there should be a fragment that is on our start boundary. 2031 */ 2032 CLIP_CHECK_BACK(start_entry, start); 2033 } 2034 2035 if (kmflags & KM_PAGEABLE) { 2036 /* 2037 * This is the unwiring case. We must first ensure that the 2038 * range to be unwired is really wired down. We know there 2039 * are no holes. 2040 */ 2041 entry = start_entry; 2042 while ((entry != &map->header) && (entry->start < end)) { 2043 if (entry->wired_count == 0) { 2044 rv = KERN_INVALID_ARGUMENT; 2045 goto done; 2046 } 2047 entry = entry->next; 2048 } 2049 2050 /* 2051 * Now decrement the wiring count for each region. If a region 2052 * becomes completely unwired, unwire its physical pages and 2053 * mappings. 2054 */ 2055 entry = start_entry; 2056 while ((entry != &map->header) && (entry->start < end)) { 2057 entry->wired_count--; 2058 if (entry->wired_count == 0) 2059 vm_fault_unwire(map, entry->start, entry->end); 2060 entry = entry->next; 2061 } 2062 } 2063 done: 2064 vm_map_unclip_range(map, start_entry, start, real_end, &count, 2065 MAP_CLIP_NO_HOLES); 2066 map->timestamp++; 2067 vm_map_unlock(map); 2068 failure: 2069 if (kmflags & KM_KRESERVE) 2070 vm_map_entry_krelease(count); 2071 else 2072 vm_map_entry_release(count); 2073 return (rv); 2074 } 2075 2076 /* 2077 * vm_map_set_wired_quick() 2078 * 2079 * Mark a newly allocated address range as wired but do not fault in 2080 * the pages. The caller is expected to load the pages into the object. 2081 * 2082 * The map must be locked on entry and will remain locked on return. 2083 */ 2084 void 2085 vm_map_set_wired_quick(vm_map_t map, vm_offset_t addr, vm_size_t size, int *countp) 2086 { 2087 vm_map_entry_t scan; 2088 vm_map_entry_t entry; 2089 2090 entry = vm_map_clip_range(map, addr, addr + size, countp, MAP_CLIP_NO_HOLES); 2091 for (scan = entry; scan != &map->header && scan->start < addr + size; scan = scan->next) { 2092 KKASSERT(entry->wired_count == 0); 2093 entry->wired_count = 1; 2094 } 2095 vm_map_unclip_range(map, entry, addr, addr + size, countp, MAP_CLIP_NO_HOLES); 2096 } 2097 2098 /* 2099 * vm_map_clean 2100 * 2101 * Push any dirty cached pages in the address range to their pager. 2102 * If syncio is TRUE, dirty pages are written synchronously. 2103 * If invalidate is TRUE, any cached pages are freed as well. 2104 * 2105 * Returns an error if any part of the specified range is not mapped. 2106 */ 2107 int 2108 vm_map_clean(vm_map_t map, vm_offset_t start, vm_offset_t end, boolean_t syncio, 2109 boolean_t invalidate) 2110 { 2111 vm_map_entry_t current; 2112 vm_map_entry_t entry; 2113 vm_size_t size; 2114 vm_object_t object; 2115 vm_ooffset_t offset; 2116 2117 vm_map_lock_read(map); 2118 VM_MAP_RANGE_CHECK(map, start, end); 2119 if (!vm_map_lookup_entry(map, start, &entry)) { 2120 vm_map_unlock_read(map); 2121 return (KERN_INVALID_ADDRESS); 2122 } 2123 /* 2124 * Make a first pass to check for holes. 2125 */ 2126 for (current = entry; current->start < end; current = current->next) { 2127 if (current->eflags & MAP_ENTRY_IS_SUB_MAP) { 2128 vm_map_unlock_read(map); 2129 return (KERN_INVALID_ARGUMENT); 2130 } 2131 if (end > current->end && 2132 (current->next == &map->header || 2133 current->end != current->next->start)) { 2134 vm_map_unlock_read(map); 2135 return (KERN_INVALID_ADDRESS); 2136 } 2137 } 2138 2139 if (invalidate) 2140 pmap_remove(vm_map_pmap(map), start, end); 2141 /* 2142 * Make a second pass, cleaning/uncaching pages from the indicated 2143 * objects as we go. 2144 */ 2145 for (current = entry; current->start < end; current = current->next) { 2146 offset = current->offset + (start - current->start); 2147 size = (end <= current->end ? end : current->end) - start; 2148 if (current->eflags & MAP_ENTRY_IS_SUB_MAP) { 2149 vm_map_t smap; 2150 vm_map_entry_t tentry; 2151 vm_size_t tsize; 2152 2153 smap = current->object.sub_map; 2154 vm_map_lock_read(smap); 2155 (void) vm_map_lookup_entry(smap, offset, &tentry); 2156 tsize = tentry->end - offset; 2157 if (tsize < size) 2158 size = tsize; 2159 object = tentry->object.vm_object; 2160 offset = tentry->offset + (offset - tentry->start); 2161 vm_map_unlock_read(smap); 2162 } else { 2163 object = current->object.vm_object; 2164 } 2165 /* 2166 * Note that there is absolutely no sense in writing out 2167 * anonymous objects, so we track down the vnode object 2168 * to write out. 2169 * We invalidate (remove) all pages from the address space 2170 * anyway, for semantic correctness. 2171 * 2172 * note: certain anonymous maps, such as MAP_NOSYNC maps, 2173 * may start out with a NULL object. 2174 */ 2175 while (object && object->backing_object) { 2176 object = object->backing_object; 2177 offset += object->backing_object_offset; 2178 if (object->size < OFF_TO_IDX( offset + size)) 2179 size = IDX_TO_OFF(object->size) - offset; 2180 } 2181 if (object && (object->type == OBJT_VNODE) && 2182 (current->protection & VM_PROT_WRITE)) { 2183 /* 2184 * Flush pages if writing is allowed, invalidate them 2185 * if invalidation requested. Pages undergoing I/O 2186 * will be ignored by vm_object_page_remove(). 2187 * 2188 * We cannot lock the vnode and then wait for paging 2189 * to complete without deadlocking against vm_fault. 2190 * Instead we simply call vm_object_page_remove() and 2191 * allow it to block internally on a page-by-page 2192 * basis when it encounters pages undergoing async 2193 * I/O. 2194 */ 2195 int flags; 2196 2197 vm_object_reference(object); 2198 vn_lock(object->handle, NULL, 2199 LK_EXCLUSIVE | LK_RETRY, curthread); 2200 flags = (syncio || invalidate) ? OBJPC_SYNC : 0; 2201 flags |= invalidate ? OBJPC_INVAL : 0; 2202 vm_object_page_clean(object, 2203 OFF_TO_IDX(offset), 2204 OFF_TO_IDX(offset + size + PAGE_MASK), 2205 flags); 2206 VOP_UNLOCK(object->handle, NULL, 0, curthread); 2207 vm_object_deallocate(object); 2208 } 2209 if (object && invalidate && 2210 ((object->type == OBJT_VNODE) || 2211 (object->type == OBJT_DEVICE))) { 2212 vm_object_reference(object); 2213 vm_object_page_remove(object, 2214 OFF_TO_IDX(offset), 2215 OFF_TO_IDX(offset + size + PAGE_MASK), 2216 TRUE); 2217 vm_object_deallocate(object); 2218 } 2219 start += size; 2220 } 2221 2222 vm_map_unlock_read(map); 2223 return (KERN_SUCCESS); 2224 } 2225 2226 /* 2227 * vm_map_entry_unwire: [ internal use only ] 2228 * 2229 * Make the region specified by this entry pageable. 2230 * 2231 * The map in question should be locked. 2232 * [This is the reason for this routine's existence.] 2233 */ 2234 static void 2235 vm_map_entry_unwire(vm_map_t map, vm_map_entry_t entry) 2236 { 2237 vm_fault_unwire(map, entry->start, entry->end); 2238 entry->wired_count = 0; 2239 } 2240 2241 /* 2242 * vm_map_entry_delete: [ internal use only ] 2243 * 2244 * Deallocate the given entry from the target map. 2245 */ 2246 static void 2247 vm_map_entry_delete(vm_map_t map, vm_map_entry_t entry, int *countp) 2248 { 2249 vm_map_entry_unlink(map, entry); 2250 map->size -= entry->end - entry->start; 2251 2252 if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) == 0) { 2253 vm_object_deallocate(entry->object.vm_object); 2254 } 2255 2256 vm_map_entry_dispose(map, entry, countp); 2257 } 2258 2259 /* 2260 * vm_map_delete: [ internal use only ] 2261 * 2262 * Deallocates the given address range from the target 2263 * map. 2264 */ 2265 int 2266 vm_map_delete(vm_map_t map, vm_offset_t start, vm_offset_t end, int *countp) 2267 { 2268 vm_object_t object; 2269 vm_map_entry_t entry; 2270 vm_map_entry_t first_entry; 2271 2272 /* 2273 * Find the start of the region, and clip it 2274 */ 2275 2276 again: 2277 if (!vm_map_lookup_entry(map, start, &first_entry)) 2278 entry = first_entry->next; 2279 else { 2280 entry = first_entry; 2281 vm_map_clip_start(map, entry, start, countp); 2282 /* 2283 * Fix the lookup hint now, rather than each time though the 2284 * loop. 2285 */ 2286 SAVE_HINT(map, entry->prev); 2287 } 2288 2289 /* 2290 * Save the free space hint 2291 */ 2292 2293 if (entry == &map->header) { 2294 map->first_free = &map->header; 2295 } else if (map->first_free->start >= start) { 2296 map->first_free = entry->prev; 2297 } 2298 2299 /* 2300 * Step through all entries in this region 2301 */ 2302 2303 while ((entry != &map->header) && (entry->start < end)) { 2304 vm_map_entry_t next; 2305 vm_offset_t s, e; 2306 vm_pindex_t offidxstart, offidxend, count; 2307 2308 /* 2309 * If we hit an in-transition entry we have to sleep and 2310 * retry. It's easier (and not really slower) to just retry 2311 * since this case occurs so rarely and the hint is already 2312 * pointing at the right place. We have to reset the 2313 * start offset so as not to accidently delete an entry 2314 * another process just created in vacated space. 2315 */ 2316 if (entry->eflags & MAP_ENTRY_IN_TRANSITION) { 2317 entry->eflags |= MAP_ENTRY_NEEDS_WAKEUP; 2318 start = entry->start; 2319 ++mycpu->gd_cnt.v_intrans_coll; 2320 ++mycpu->gd_cnt.v_intrans_wait; 2321 vm_map_transition_wait(map); 2322 goto again; 2323 } 2324 vm_map_clip_end(map, entry, end, countp); 2325 2326 s = entry->start; 2327 e = entry->end; 2328 next = entry->next; 2329 2330 offidxstart = OFF_TO_IDX(entry->offset); 2331 count = OFF_TO_IDX(e - s); 2332 object = entry->object.vm_object; 2333 2334 /* 2335 * Unwire before removing addresses from the pmap; otherwise, 2336 * unwiring will put the entries back in the pmap. 2337 */ 2338 if (entry->wired_count != 0) { 2339 vm_map_entry_unwire(map, entry); 2340 } 2341 2342 offidxend = offidxstart + count; 2343 2344 if ((object == kernel_object) || (object == kmem_object)) { 2345 vm_object_page_remove(object, offidxstart, offidxend, FALSE); 2346 } else { 2347 pmap_remove(map->pmap, s, e); 2348 if (object != NULL && 2349 object->ref_count != 1 && 2350 (object->flags & (OBJ_NOSPLIT|OBJ_ONEMAPPING)) == OBJ_ONEMAPPING && 2351 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) { 2352 vm_object_collapse(object); 2353 vm_object_page_remove(object, offidxstart, offidxend, FALSE); 2354 if (object->type == OBJT_SWAP) { 2355 swap_pager_freespace(object, offidxstart, count); 2356 } 2357 if (offidxend >= object->size && 2358 offidxstart < object->size) { 2359 object->size = offidxstart; 2360 } 2361 } 2362 } 2363 2364 /* 2365 * Delete the entry (which may delete the object) only after 2366 * removing all pmap entries pointing to its pages. 2367 * (Otherwise, its page frames may be reallocated, and any 2368 * modify bits will be set in the wrong object!) 2369 */ 2370 vm_map_entry_delete(map, entry, countp); 2371 entry = next; 2372 } 2373 return (KERN_SUCCESS); 2374 } 2375 2376 /* 2377 * vm_map_remove: 2378 * 2379 * Remove the given address range from the target map. 2380 * This is the exported form of vm_map_delete. 2381 */ 2382 int 2383 vm_map_remove(vm_map_t map, vm_offset_t start, vm_offset_t end) 2384 { 2385 int result; 2386 int count; 2387 2388 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 2389 vm_map_lock(map); 2390 VM_MAP_RANGE_CHECK(map, start, end); 2391 result = vm_map_delete(map, start, end, &count); 2392 vm_map_unlock(map); 2393 vm_map_entry_release(count); 2394 2395 return (result); 2396 } 2397 2398 /* 2399 * vm_map_check_protection: 2400 * 2401 * Assert that the target map allows the specified 2402 * privilege on the entire address region given. 2403 * The entire region must be allocated. 2404 */ 2405 boolean_t 2406 vm_map_check_protection(vm_map_t map, vm_offset_t start, vm_offset_t end, 2407 vm_prot_t protection) 2408 { 2409 vm_map_entry_t entry; 2410 vm_map_entry_t tmp_entry; 2411 2412 if (!vm_map_lookup_entry(map, start, &tmp_entry)) { 2413 return (FALSE); 2414 } 2415 entry = tmp_entry; 2416 2417 while (start < end) { 2418 if (entry == &map->header) { 2419 return (FALSE); 2420 } 2421 /* 2422 * No holes allowed! 2423 */ 2424 2425 if (start < entry->start) { 2426 return (FALSE); 2427 } 2428 /* 2429 * Check protection associated with entry. 2430 */ 2431 2432 if ((entry->protection & protection) != protection) { 2433 return (FALSE); 2434 } 2435 /* go to next entry */ 2436 2437 start = entry->end; 2438 entry = entry->next; 2439 } 2440 return (TRUE); 2441 } 2442 2443 /* 2444 * Split the pages in a map entry into a new object. This affords 2445 * easier removal of unused pages, and keeps object inheritance from 2446 * being a negative impact on memory usage. 2447 */ 2448 static void 2449 vm_map_split(vm_map_entry_t entry) 2450 { 2451 vm_page_t m; 2452 vm_object_t orig_object, new_object, source; 2453 vm_offset_t s, e; 2454 vm_pindex_t offidxstart, offidxend, idx; 2455 vm_size_t size; 2456 vm_ooffset_t offset; 2457 2458 orig_object = entry->object.vm_object; 2459 if (orig_object->type != OBJT_DEFAULT && orig_object->type != OBJT_SWAP) 2460 return; 2461 if (orig_object->ref_count <= 1) 2462 return; 2463 2464 offset = entry->offset; 2465 s = entry->start; 2466 e = entry->end; 2467 2468 offidxstart = OFF_TO_IDX(offset); 2469 offidxend = offidxstart + OFF_TO_IDX(e - s); 2470 size = offidxend - offidxstart; 2471 2472 new_object = vm_pager_allocate(orig_object->type, 2473 NULL, IDX_TO_OFF(size), VM_PROT_ALL, 0LL); 2474 if (new_object == NULL) 2475 return; 2476 2477 source = orig_object->backing_object; 2478 if (source != NULL) { 2479 vm_object_reference(source); /* Referenced by new_object */ 2480 LIST_INSERT_HEAD(&source->shadow_head, 2481 new_object, shadow_list); 2482 vm_object_clear_flag(source, OBJ_ONEMAPPING); 2483 new_object->backing_object_offset = 2484 orig_object->backing_object_offset + IDX_TO_OFF(offidxstart); 2485 new_object->backing_object = source; 2486 source->shadow_count++; 2487 source->generation++; 2488 } 2489 2490 for (idx = 0; idx < size; idx++) { 2491 vm_page_t m; 2492 int ss; /* s used */ 2493 2494 /* 2495 * splvm protection is required to avoid a race between 2496 * the lookup and an interrupt/unbusy/free and our busy 2497 * check. 2498 */ 2499 ss = splvm(); 2500 retry: 2501 m = vm_page_lookup(orig_object, offidxstart + idx); 2502 if (m == NULL) { 2503 splx(ss); 2504 continue; 2505 } 2506 2507 /* 2508 * We must wait for pending I/O to complete before we can 2509 * rename the page. 2510 * 2511 * We do not have to VM_PROT_NONE the page as mappings should 2512 * not be changed by this operation. 2513 */ 2514 if (vm_page_sleep_busy(m, TRUE, "spltwt")) 2515 goto retry; 2516 vm_page_busy(m); 2517 vm_page_rename(m, new_object, idx); 2518 /* page automatically made dirty by rename and cache handled */ 2519 vm_page_busy(m); 2520 splx(ss); 2521 } 2522 2523 if (orig_object->type == OBJT_SWAP) { 2524 vm_object_pip_add(orig_object, 1); 2525 /* 2526 * copy orig_object pages into new_object 2527 * and destroy unneeded pages in 2528 * shadow object. 2529 */ 2530 swap_pager_copy(orig_object, new_object, offidxstart, 0); 2531 vm_object_pip_wakeup(orig_object); 2532 } 2533 2534 /* 2535 * Wakeup the pages we played with. No spl protection is needed 2536 * for a simple wakeup. 2537 */ 2538 for (idx = 0; idx < size; idx++) { 2539 m = vm_page_lookup(new_object, idx); 2540 if (m) 2541 vm_page_wakeup(m); 2542 } 2543 2544 entry->object.vm_object = new_object; 2545 entry->offset = 0LL; 2546 vm_object_deallocate(orig_object); 2547 } 2548 2549 /* 2550 * vm_map_copy_entry: 2551 * 2552 * Copies the contents of the source entry to the destination 2553 * entry. The entries *must* be aligned properly. 2554 */ 2555 static void 2556 vm_map_copy_entry(vm_map_t src_map, vm_map_t dst_map, 2557 vm_map_entry_t src_entry, vm_map_entry_t dst_entry) 2558 { 2559 vm_object_t src_object; 2560 2561 if ((dst_entry->eflags|src_entry->eflags) & MAP_ENTRY_IS_SUB_MAP) 2562 return; 2563 2564 if (src_entry->wired_count == 0) { 2565 2566 /* 2567 * If the source entry is marked needs_copy, it is already 2568 * write-protected. 2569 */ 2570 if ((src_entry->eflags & MAP_ENTRY_NEEDS_COPY) == 0) { 2571 pmap_protect(src_map->pmap, 2572 src_entry->start, 2573 src_entry->end, 2574 src_entry->protection & ~VM_PROT_WRITE); 2575 } 2576 2577 /* 2578 * Make a copy of the object. 2579 */ 2580 if ((src_object = src_entry->object.vm_object) != NULL) { 2581 2582 if ((src_object->handle == NULL) && 2583 (src_object->type == OBJT_DEFAULT || 2584 src_object->type == OBJT_SWAP)) { 2585 vm_object_collapse(src_object); 2586 if ((src_object->flags & (OBJ_NOSPLIT|OBJ_ONEMAPPING)) == OBJ_ONEMAPPING) { 2587 vm_map_split(src_entry); 2588 src_object = src_entry->object.vm_object; 2589 } 2590 } 2591 2592 vm_object_reference(src_object); 2593 vm_object_clear_flag(src_object, OBJ_ONEMAPPING); 2594 dst_entry->object.vm_object = src_object; 2595 src_entry->eflags |= (MAP_ENTRY_COW|MAP_ENTRY_NEEDS_COPY); 2596 dst_entry->eflags |= (MAP_ENTRY_COW|MAP_ENTRY_NEEDS_COPY); 2597 dst_entry->offset = src_entry->offset; 2598 } else { 2599 dst_entry->object.vm_object = NULL; 2600 dst_entry->offset = 0; 2601 } 2602 2603 pmap_copy(dst_map->pmap, src_map->pmap, dst_entry->start, 2604 dst_entry->end - dst_entry->start, src_entry->start); 2605 } else { 2606 /* 2607 * Of course, wired down pages can't be set copy-on-write. 2608 * Cause wired pages to be copied into the new map by 2609 * simulating faults (the new pages are pageable) 2610 */ 2611 vm_fault_copy_entry(dst_map, src_map, dst_entry, src_entry); 2612 } 2613 } 2614 2615 /* 2616 * vmspace_fork: 2617 * Create a new process vmspace structure and vm_map 2618 * based on those of an existing process. The new map 2619 * is based on the old map, according to the inheritance 2620 * values on the regions in that map. 2621 * 2622 * The source map must not be locked. 2623 */ 2624 struct vmspace * 2625 vmspace_fork(struct vmspace *vm1) 2626 { 2627 struct vmspace *vm2; 2628 vm_map_t old_map = &vm1->vm_map; 2629 vm_map_t new_map; 2630 vm_map_entry_t old_entry; 2631 vm_map_entry_t new_entry; 2632 vm_object_t object; 2633 int count; 2634 2635 vm_map_lock(old_map); 2636 old_map->infork = 1; 2637 2638 /* 2639 * XXX Note: upcalls are not copied. 2640 */ 2641 vm2 = vmspace_alloc(old_map->min_offset, old_map->max_offset); 2642 bcopy(&vm1->vm_startcopy, &vm2->vm_startcopy, 2643 (caddr_t)&vm1->vm_endcopy - (caddr_t)&vm1->vm_startcopy); 2644 new_map = &vm2->vm_map; /* XXX */ 2645 new_map->timestamp = 1; 2646 2647 count = 0; 2648 old_entry = old_map->header.next; 2649 while (old_entry != &old_map->header) { 2650 ++count; 2651 old_entry = old_entry->next; 2652 } 2653 2654 count = vm_map_entry_reserve(count + MAP_RESERVE_COUNT); 2655 2656 old_entry = old_map->header.next; 2657 while (old_entry != &old_map->header) { 2658 if (old_entry->eflags & MAP_ENTRY_IS_SUB_MAP) 2659 panic("vm_map_fork: encountered a submap"); 2660 2661 switch (old_entry->inheritance) { 2662 case VM_INHERIT_NONE: 2663 break; 2664 2665 case VM_INHERIT_SHARE: 2666 /* 2667 * Clone the entry, creating the shared object if necessary. 2668 */ 2669 object = old_entry->object.vm_object; 2670 if (object == NULL) { 2671 object = vm_object_allocate(OBJT_DEFAULT, 2672 atop(old_entry->end - old_entry->start)); 2673 old_entry->object.vm_object = object; 2674 old_entry->offset = (vm_offset_t) 0; 2675 } 2676 2677 /* 2678 * Add the reference before calling vm_object_shadow 2679 * to insure that a shadow object is created. 2680 */ 2681 vm_object_reference(object); 2682 if (old_entry->eflags & MAP_ENTRY_NEEDS_COPY) { 2683 vm_object_shadow(&old_entry->object.vm_object, 2684 &old_entry->offset, 2685 atop(old_entry->end - old_entry->start)); 2686 old_entry->eflags &= ~MAP_ENTRY_NEEDS_COPY; 2687 /* Transfer the second reference too. */ 2688 vm_object_reference( 2689 old_entry->object.vm_object); 2690 vm_object_deallocate(object); 2691 object = old_entry->object.vm_object; 2692 } 2693 vm_object_clear_flag(object, OBJ_ONEMAPPING); 2694 2695 /* 2696 * Clone the entry, referencing the shared object. 2697 */ 2698 new_entry = vm_map_entry_create(new_map, &count); 2699 *new_entry = *old_entry; 2700 new_entry->eflags &= ~MAP_ENTRY_USER_WIRED; 2701 new_entry->wired_count = 0; 2702 2703 /* 2704 * Insert the entry into the new map -- we know we're 2705 * inserting at the end of the new map. 2706 */ 2707 2708 vm_map_entry_link(new_map, new_map->header.prev, 2709 new_entry); 2710 2711 /* 2712 * Update the physical map 2713 */ 2714 2715 pmap_copy(new_map->pmap, old_map->pmap, 2716 new_entry->start, 2717 (old_entry->end - old_entry->start), 2718 old_entry->start); 2719 break; 2720 2721 case VM_INHERIT_COPY: 2722 /* 2723 * Clone the entry and link into the map. 2724 */ 2725 new_entry = vm_map_entry_create(new_map, &count); 2726 *new_entry = *old_entry; 2727 new_entry->eflags &= ~MAP_ENTRY_USER_WIRED; 2728 new_entry->wired_count = 0; 2729 new_entry->object.vm_object = NULL; 2730 vm_map_entry_link(new_map, new_map->header.prev, 2731 new_entry); 2732 vm_map_copy_entry(old_map, new_map, old_entry, 2733 new_entry); 2734 break; 2735 } 2736 old_entry = old_entry->next; 2737 } 2738 2739 new_map->size = old_map->size; 2740 old_map->infork = 0; 2741 vm_map_unlock(old_map); 2742 vm_map_entry_release(count); 2743 2744 return (vm2); 2745 } 2746 2747 int 2748 vm_map_stack (vm_map_t map, vm_offset_t addrbos, vm_size_t max_ssize, 2749 vm_prot_t prot, vm_prot_t max, int cow) 2750 { 2751 vm_map_entry_t prev_entry; 2752 vm_map_entry_t new_stack_entry; 2753 vm_size_t init_ssize; 2754 int rv; 2755 int count; 2756 2757 if (VM_MIN_ADDRESS > 0 && addrbos < VM_MIN_ADDRESS) 2758 return (KERN_NO_SPACE); 2759 2760 if (max_ssize < sgrowsiz) 2761 init_ssize = max_ssize; 2762 else 2763 init_ssize = sgrowsiz; 2764 2765 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 2766 vm_map_lock(map); 2767 2768 /* If addr is already mapped, no go */ 2769 if (vm_map_lookup_entry(map, addrbos, &prev_entry)) { 2770 vm_map_unlock(map); 2771 vm_map_entry_release(count); 2772 return (KERN_NO_SPACE); 2773 } 2774 2775 /* If we would blow our VMEM resource limit, no go */ 2776 if (map->size + init_ssize > 2777 curproc->p_rlimit[RLIMIT_VMEM].rlim_cur) { 2778 vm_map_unlock(map); 2779 vm_map_entry_release(count); 2780 return (KERN_NO_SPACE); 2781 } 2782 2783 /* If we can't accomodate max_ssize in the current mapping, 2784 * no go. However, we need to be aware that subsequent user 2785 * mappings might map into the space we have reserved for 2786 * stack, and currently this space is not protected. 2787 * 2788 * Hopefully we will at least detect this condition 2789 * when we try to grow the stack. 2790 */ 2791 if ((prev_entry->next != &map->header) && 2792 (prev_entry->next->start < addrbos + max_ssize)) { 2793 vm_map_unlock(map); 2794 vm_map_entry_release(count); 2795 return (KERN_NO_SPACE); 2796 } 2797 2798 /* We initially map a stack of only init_ssize. We will 2799 * grow as needed later. Since this is to be a grow 2800 * down stack, we map at the top of the range. 2801 * 2802 * Note: we would normally expect prot and max to be 2803 * VM_PROT_ALL, and cow to be 0. Possibly we should 2804 * eliminate these as input parameters, and just 2805 * pass these values here in the insert call. 2806 */ 2807 rv = vm_map_insert(map, &count, 2808 NULL, 0, addrbos + max_ssize - init_ssize, 2809 addrbos + max_ssize, prot, max, cow); 2810 2811 /* Now set the avail_ssize amount */ 2812 if (rv == KERN_SUCCESS){ 2813 if (prev_entry != &map->header) 2814 vm_map_clip_end(map, prev_entry, addrbos + max_ssize - init_ssize, &count); 2815 new_stack_entry = prev_entry->next; 2816 if (new_stack_entry->end != addrbos + max_ssize || 2817 new_stack_entry->start != addrbos + max_ssize - init_ssize) 2818 panic ("Bad entry start/end for new stack entry"); 2819 else 2820 new_stack_entry->avail_ssize = max_ssize - init_ssize; 2821 } 2822 2823 vm_map_unlock(map); 2824 vm_map_entry_release(count); 2825 return (rv); 2826 } 2827 2828 /* Attempts to grow a vm stack entry. Returns KERN_SUCCESS if the 2829 * desired address is already mapped, or if we successfully grow 2830 * the stack. Also returns KERN_SUCCESS if addr is outside the 2831 * stack range (this is strange, but preserves compatibility with 2832 * the grow function in vm_machdep.c). 2833 */ 2834 int 2835 vm_map_growstack (struct proc *p, vm_offset_t addr) 2836 { 2837 vm_map_entry_t prev_entry; 2838 vm_map_entry_t stack_entry; 2839 vm_map_entry_t new_stack_entry; 2840 struct vmspace *vm = p->p_vmspace; 2841 vm_map_t map = &vm->vm_map; 2842 vm_offset_t end; 2843 int grow_amount; 2844 int rv = KERN_SUCCESS; 2845 int is_procstack; 2846 int use_read_lock = 1; 2847 int count; 2848 2849 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 2850 Retry: 2851 if (use_read_lock) 2852 vm_map_lock_read(map); 2853 else 2854 vm_map_lock(map); 2855 2856 /* If addr is already in the entry range, no need to grow.*/ 2857 if (vm_map_lookup_entry(map, addr, &prev_entry)) 2858 goto done; 2859 2860 if ((stack_entry = prev_entry->next) == &map->header) 2861 goto done; 2862 if (prev_entry == &map->header) 2863 end = stack_entry->start - stack_entry->avail_ssize; 2864 else 2865 end = prev_entry->end; 2866 2867 /* This next test mimics the old grow function in vm_machdep.c. 2868 * It really doesn't quite make sense, but we do it anyway 2869 * for compatibility. 2870 * 2871 * If not growable stack, return success. This signals the 2872 * caller to proceed as he would normally with normal vm. 2873 */ 2874 if (stack_entry->avail_ssize < 1 || 2875 addr >= stack_entry->start || 2876 addr < stack_entry->start - stack_entry->avail_ssize) { 2877 goto done; 2878 } 2879 2880 /* Find the minimum grow amount */ 2881 grow_amount = roundup (stack_entry->start - addr, PAGE_SIZE); 2882 if (grow_amount > stack_entry->avail_ssize) { 2883 rv = KERN_NO_SPACE; 2884 goto done; 2885 } 2886 2887 /* If there is no longer enough space between the entries 2888 * nogo, and adjust the available space. Note: this 2889 * should only happen if the user has mapped into the 2890 * stack area after the stack was created, and is 2891 * probably an error. 2892 * 2893 * This also effectively destroys any guard page the user 2894 * might have intended by limiting the stack size. 2895 */ 2896 if (grow_amount > stack_entry->start - end) { 2897 if (use_read_lock && vm_map_lock_upgrade(map)) { 2898 use_read_lock = 0; 2899 goto Retry; 2900 } 2901 use_read_lock = 0; 2902 stack_entry->avail_ssize = stack_entry->start - end; 2903 rv = KERN_NO_SPACE; 2904 goto done; 2905 } 2906 2907 is_procstack = addr >= (vm_offset_t)vm->vm_maxsaddr; 2908 2909 /* If this is the main process stack, see if we're over the 2910 * stack limit. 2911 */ 2912 if (is_procstack && (ctob(vm->vm_ssize) + grow_amount > 2913 p->p_rlimit[RLIMIT_STACK].rlim_cur)) { 2914 rv = KERN_NO_SPACE; 2915 goto done; 2916 } 2917 2918 /* Round up the grow amount modulo SGROWSIZ */ 2919 grow_amount = roundup (grow_amount, sgrowsiz); 2920 if (grow_amount > stack_entry->avail_ssize) { 2921 grow_amount = stack_entry->avail_ssize; 2922 } 2923 if (is_procstack && (ctob(vm->vm_ssize) + grow_amount > 2924 p->p_rlimit[RLIMIT_STACK].rlim_cur)) { 2925 grow_amount = p->p_rlimit[RLIMIT_STACK].rlim_cur - 2926 ctob(vm->vm_ssize); 2927 } 2928 2929 /* If we would blow our VMEM resource limit, no go */ 2930 if (map->size + grow_amount > p->p_rlimit[RLIMIT_VMEM].rlim_cur) { 2931 rv = KERN_NO_SPACE; 2932 goto done; 2933 } 2934 2935 if (use_read_lock && vm_map_lock_upgrade(map)) { 2936 use_read_lock = 0; 2937 goto Retry; 2938 } 2939 use_read_lock = 0; 2940 2941 /* Get the preliminary new entry start value */ 2942 addr = stack_entry->start - grow_amount; 2943 2944 /* If this puts us into the previous entry, cut back our growth 2945 * to the available space. Also, see the note above. 2946 */ 2947 if (addr < end) { 2948 stack_entry->avail_ssize = stack_entry->start - end; 2949 addr = end; 2950 } 2951 2952 rv = vm_map_insert(map, &count, 2953 NULL, 0, addr, stack_entry->start, 2954 VM_PROT_ALL, 2955 VM_PROT_ALL, 2956 0); 2957 2958 /* Adjust the available stack space by the amount we grew. */ 2959 if (rv == KERN_SUCCESS) { 2960 if (prev_entry != &map->header) 2961 vm_map_clip_end(map, prev_entry, addr, &count); 2962 new_stack_entry = prev_entry->next; 2963 if (new_stack_entry->end != stack_entry->start || 2964 new_stack_entry->start != addr) 2965 panic ("Bad stack grow start/end in new stack entry"); 2966 else { 2967 new_stack_entry->avail_ssize = stack_entry->avail_ssize - 2968 (new_stack_entry->end - 2969 new_stack_entry->start); 2970 if (is_procstack) 2971 vm->vm_ssize += btoc(new_stack_entry->end - 2972 new_stack_entry->start); 2973 } 2974 } 2975 2976 done: 2977 if (use_read_lock) 2978 vm_map_unlock_read(map); 2979 else 2980 vm_map_unlock(map); 2981 vm_map_entry_release(count); 2982 return (rv); 2983 } 2984 2985 /* 2986 * Unshare the specified VM space for exec. If other processes are 2987 * mapped to it, then create a new one. The new vmspace is null. 2988 */ 2989 2990 void 2991 vmspace_exec(struct proc *p, struct vmspace *vmcopy) 2992 { 2993 struct vmspace *oldvmspace = p->p_vmspace; 2994 struct vmspace *newvmspace; 2995 vm_map_t map = &p->p_vmspace->vm_map; 2996 2997 /* 2998 * If we are execing a resident vmspace we fork it, otherwise 2999 * we create a new vmspace. Note that exitingcnt and upcalls 3000 * are not copied to the new vmspace. 3001 */ 3002 if (vmcopy) { 3003 newvmspace = vmspace_fork(vmcopy); 3004 } else { 3005 newvmspace = vmspace_alloc(map->min_offset, map->max_offset); 3006 bcopy(&oldvmspace->vm_startcopy, &newvmspace->vm_startcopy, 3007 (caddr_t)&oldvmspace->vm_endcopy - 3008 (caddr_t)&oldvmspace->vm_startcopy); 3009 } 3010 3011 /* 3012 * This code is written like this for prototype purposes. The 3013 * goal is to avoid running down the vmspace here, but let the 3014 * other process's that are still using the vmspace to finally 3015 * run it down. Even though there is little or no chance of blocking 3016 * here, it is a good idea to keep this form for future mods. 3017 */ 3018 p->p_vmspace = newvmspace; 3019 pmap_pinit2(vmspace_pmap(newvmspace)); 3020 if (p == curproc) 3021 pmap_activate(p); 3022 vmspace_free(oldvmspace); 3023 } 3024 3025 /* 3026 * Unshare the specified VM space for forcing COW. This 3027 * is called by rfork, for the (RFMEM|RFPROC) == 0 case. 3028 * 3029 * The exitingcnt test is not strictly necessary but has been 3030 * included for code sanity (to make the code a bit more deterministic). 3031 */ 3032 3033 void 3034 vmspace_unshare(struct proc *p) 3035 { 3036 struct vmspace *oldvmspace = p->p_vmspace; 3037 struct vmspace *newvmspace; 3038 3039 if (oldvmspace->vm_refcnt == 1 && oldvmspace->vm_exitingcnt == 0) 3040 return; 3041 newvmspace = vmspace_fork(oldvmspace); 3042 p->p_vmspace = newvmspace; 3043 pmap_pinit2(vmspace_pmap(newvmspace)); 3044 if (p == curproc) 3045 pmap_activate(p); 3046 vmspace_free(oldvmspace); 3047 } 3048 3049 /* 3050 * vm_map_lookup: 3051 * 3052 * Finds the VM object, offset, and 3053 * protection for a given virtual address in the 3054 * specified map, assuming a page fault of the 3055 * type specified. 3056 * 3057 * Leaves the map in question locked for read; return 3058 * values are guaranteed until a vm_map_lookup_done 3059 * call is performed. Note that the map argument 3060 * is in/out; the returned map must be used in 3061 * the call to vm_map_lookup_done. 3062 * 3063 * A handle (out_entry) is returned for use in 3064 * vm_map_lookup_done, to make that fast. 3065 * 3066 * If a lookup is requested with "write protection" 3067 * specified, the map may be changed to perform virtual 3068 * copying operations, although the data referenced will 3069 * remain the same. 3070 */ 3071 int 3072 vm_map_lookup(vm_map_t *var_map, /* IN/OUT */ 3073 vm_offset_t vaddr, 3074 vm_prot_t fault_typea, 3075 vm_map_entry_t *out_entry, /* OUT */ 3076 vm_object_t *object, /* OUT */ 3077 vm_pindex_t *pindex, /* OUT */ 3078 vm_prot_t *out_prot, /* OUT */ 3079 boolean_t *wired) /* OUT */ 3080 { 3081 vm_map_entry_t entry; 3082 vm_map_t map = *var_map; 3083 vm_prot_t prot; 3084 vm_prot_t fault_type = fault_typea; 3085 int use_read_lock = 1; 3086 int rv = KERN_SUCCESS; 3087 3088 RetryLookup: 3089 if (use_read_lock) 3090 vm_map_lock_read(map); 3091 else 3092 vm_map_lock(map); 3093 3094 /* 3095 * If the map has an interesting hint, try it before calling full 3096 * blown lookup routine. 3097 */ 3098 entry = map->hint; 3099 *out_entry = entry; 3100 3101 if ((entry == &map->header) || 3102 (vaddr < entry->start) || (vaddr >= entry->end)) { 3103 vm_map_entry_t tmp_entry; 3104 3105 /* 3106 * Entry was either not a valid hint, or the vaddr was not 3107 * contained in the entry, so do a full lookup. 3108 */ 3109 if (!vm_map_lookup_entry(map, vaddr, &tmp_entry)) { 3110 rv = KERN_INVALID_ADDRESS; 3111 goto done; 3112 } 3113 3114 entry = tmp_entry; 3115 *out_entry = entry; 3116 } 3117 3118 /* 3119 * Handle submaps. 3120 */ 3121 3122 if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) { 3123 vm_map_t old_map = map; 3124 3125 *var_map = map = entry->object.sub_map; 3126 if (use_read_lock) 3127 vm_map_unlock_read(old_map); 3128 else 3129 vm_map_unlock(old_map); 3130 use_read_lock = 1; 3131 goto RetryLookup; 3132 } 3133 3134 /* 3135 * Check whether this task is allowed to have this page. 3136 * Note the special case for MAP_ENTRY_COW 3137 * pages with an override. This is to implement a forced 3138 * COW for debuggers. 3139 */ 3140 3141 if (fault_type & VM_PROT_OVERRIDE_WRITE) 3142 prot = entry->max_protection; 3143 else 3144 prot = entry->protection; 3145 3146 fault_type &= (VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 3147 if ((fault_type & prot) != fault_type) { 3148 rv = KERN_PROTECTION_FAILURE; 3149 goto done; 3150 } 3151 3152 if ((entry->eflags & MAP_ENTRY_USER_WIRED) && 3153 (entry->eflags & MAP_ENTRY_COW) && 3154 (fault_type & VM_PROT_WRITE) && 3155 (fault_typea & VM_PROT_OVERRIDE_WRITE) == 0) { 3156 rv = KERN_PROTECTION_FAILURE; 3157 goto done; 3158 } 3159 3160 /* 3161 * If this page is not pageable, we have to get it for all possible 3162 * accesses. 3163 */ 3164 3165 *wired = (entry->wired_count != 0); 3166 if (*wired) 3167 prot = fault_type = entry->protection; 3168 3169 /* 3170 * If the entry was copy-on-write, we either ... 3171 */ 3172 3173 if (entry->eflags & MAP_ENTRY_NEEDS_COPY) { 3174 /* 3175 * If we want to write the page, we may as well handle that 3176 * now since we've got the map locked. 3177 * 3178 * If we don't need to write the page, we just demote the 3179 * permissions allowed. 3180 */ 3181 3182 if (fault_type & VM_PROT_WRITE) { 3183 /* 3184 * Make a new object, and place it in the object 3185 * chain. Note that no new references have appeared 3186 * -- one just moved from the map to the new 3187 * object. 3188 */ 3189 3190 if (use_read_lock && vm_map_lock_upgrade(map)) { 3191 use_read_lock = 0; 3192 goto RetryLookup; 3193 } 3194 use_read_lock = 0; 3195 3196 vm_object_shadow( 3197 &entry->object.vm_object, 3198 &entry->offset, 3199 atop(entry->end - entry->start)); 3200 3201 entry->eflags &= ~MAP_ENTRY_NEEDS_COPY; 3202 } else { 3203 /* 3204 * We're attempting to read a copy-on-write page -- 3205 * don't allow writes. 3206 */ 3207 3208 prot &= ~VM_PROT_WRITE; 3209 } 3210 } 3211 3212 /* 3213 * Create an object if necessary. 3214 */ 3215 if (entry->object.vm_object == NULL && 3216 !map->system_map) { 3217 if (use_read_lock && vm_map_lock_upgrade(map)) { 3218 use_read_lock = 0; 3219 goto RetryLookup; 3220 } 3221 use_read_lock = 0; 3222 entry->object.vm_object = vm_object_allocate(OBJT_DEFAULT, 3223 atop(entry->end - entry->start)); 3224 entry->offset = 0; 3225 } 3226 3227 /* 3228 * Return the object/offset from this entry. If the entry was 3229 * copy-on-write or empty, it has been fixed up. 3230 */ 3231 3232 *pindex = OFF_TO_IDX((vaddr - entry->start) + entry->offset); 3233 *object = entry->object.vm_object; 3234 3235 /* 3236 * Return whether this is the only map sharing this data. On 3237 * success we return with a read lock held on the map. On failure 3238 * we return with the map unlocked. 3239 */ 3240 *out_prot = prot; 3241 done: 3242 if (rv == KERN_SUCCESS) { 3243 if (use_read_lock == 0) 3244 vm_map_lock_downgrade(map); 3245 } else if (use_read_lock) { 3246 vm_map_unlock_read(map); 3247 } else { 3248 vm_map_unlock(map); 3249 } 3250 return (rv); 3251 } 3252 3253 /* 3254 * vm_map_lookup_done: 3255 * 3256 * Releases locks acquired by a vm_map_lookup 3257 * (according to the handle returned by that lookup). 3258 */ 3259 3260 void 3261 vm_map_lookup_done(vm_map_t map, vm_map_entry_t entry, int count) 3262 { 3263 /* 3264 * Unlock the main-level map 3265 */ 3266 vm_map_unlock_read(map); 3267 if (count) 3268 vm_map_entry_release(count); 3269 } 3270 3271 #ifdef ENABLE_VFS_IOOPT 3272 3273 /* 3274 * Implement uiomove with VM operations. This handles (and collateral changes) 3275 * support every combination of source object modification, and COW type 3276 * operations. 3277 * 3278 * XXX this is extremely dangerous, enabling this option is NOT recommended. 3279 */ 3280 int 3281 vm_uiomove(vm_map_t mapa, vm_object_t srcobject, off_t cp, int cnta, 3282 vm_offset_t uaddra, int *npages) 3283 { 3284 vm_map_t map; 3285 vm_object_t first_object, oldobject, object; 3286 vm_map_entry_t entry; 3287 vm_prot_t prot; 3288 boolean_t wired; 3289 int tcnt, rv; 3290 vm_offset_t uaddr, start, end, tend; 3291 vm_pindex_t first_pindex, osize, oindex; 3292 off_t ooffset; 3293 int cnt; 3294 int count; 3295 int s; 3296 3297 if (npages) 3298 *npages = 0; 3299 3300 cnt = cnta; 3301 uaddr = uaddra; 3302 3303 while (cnt > 0) { 3304 map = mapa; 3305 3306 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 3307 3308 if ((vm_map_lookup(&map, uaddr, 3309 VM_PROT_READ, &entry, &first_object, 3310 &first_pindex, &prot, &wired)) != KERN_SUCCESS) { 3311 return EFAULT; 3312 } 3313 3314 vm_map_clip_start(map, entry, uaddr, &count); 3315 3316 tcnt = cnt; 3317 tend = uaddr + tcnt; 3318 if (tend > entry->end) { 3319 tcnt = entry->end - uaddr; 3320 tend = entry->end; 3321 } 3322 3323 vm_map_clip_end(map, entry, tend, &count); 3324 3325 start = entry->start; 3326 end = entry->end; 3327 3328 osize = atop(tcnt); 3329 3330 oindex = OFF_TO_IDX(cp); 3331 if (npages) { 3332 vm_pindex_t idx; 3333 3334 /* 3335 * spl protection is needed to avoid a race between 3336 * the lookup and an interrupt/unbusy/free occuring 3337 * prior to our busy check. 3338 */ 3339 s = splvm(); 3340 for (idx = 0; idx < osize; idx++) { 3341 vm_page_t m; 3342 if ((m = vm_page_lookup(srcobject, oindex + idx)) == NULL) { 3343 splx(s); 3344 vm_map_lookup_done(map, entry, count); 3345 return 0; 3346 } 3347 /* 3348 * disallow busy or invalid pages, but allow 3349 * m->busy pages if they are entirely valid. 3350 */ 3351 if ((m->flags & PG_BUSY) || 3352 ((m->valid & VM_PAGE_BITS_ALL) != VM_PAGE_BITS_ALL)) { 3353 splx(s); 3354 vm_map_lookup_done(map, entry, count); 3355 return 0; 3356 } 3357 } 3358 splx(s); 3359 } 3360 3361 /* 3362 * If we are changing an existing map entry, just redirect 3363 * the object, and change mappings. 3364 */ 3365 if ((first_object->type == OBJT_VNODE) && 3366 ((oldobject = entry->object.vm_object) == first_object)) { 3367 3368 if ((entry->offset != cp) || (oldobject != srcobject)) { 3369 /* 3370 * Remove old window into the file 3371 */ 3372 pmap_remove (map->pmap, uaddr, tend); 3373 3374 /* 3375 * Force copy on write for mmaped regions 3376 */ 3377 vm_object_pmap_copy_1 (srcobject, oindex, oindex + osize); 3378 3379 /* 3380 * Point the object appropriately 3381 */ 3382 if (oldobject != srcobject) { 3383 3384 /* 3385 * Set the object optimization hint flag 3386 */ 3387 vm_object_set_flag(srcobject, OBJ_OPT); 3388 vm_object_reference(srcobject); 3389 entry->object.vm_object = srcobject; 3390 3391 if (oldobject) { 3392 vm_object_deallocate(oldobject); 3393 } 3394 } 3395 3396 entry->offset = cp; 3397 map->timestamp++; 3398 } else { 3399 pmap_remove (map->pmap, uaddr, tend); 3400 } 3401 3402 } else if ((first_object->ref_count == 1) && 3403 (first_object->size == osize) && 3404 ((first_object->type == OBJT_DEFAULT) || 3405 (first_object->type == OBJT_SWAP)) ) { 3406 3407 oldobject = first_object->backing_object; 3408 3409 if ((first_object->backing_object_offset != cp) || 3410 (oldobject != srcobject)) { 3411 /* 3412 * Remove old window into the file 3413 */ 3414 pmap_remove (map->pmap, uaddr, tend); 3415 3416 /* 3417 * Remove unneeded old pages 3418 */ 3419 vm_object_page_remove(first_object, 0, 0, 0); 3420 3421 /* 3422 * Invalidate swap space 3423 */ 3424 if (first_object->type == OBJT_SWAP) { 3425 swap_pager_freespace(first_object, 3426 0, 3427 first_object->size); 3428 } 3429 3430 /* 3431 * Force copy on write for mmaped regions 3432 */ 3433 vm_object_pmap_copy_1 (srcobject, oindex, oindex + osize); 3434 3435 /* 3436 * Point the object appropriately 3437 */ 3438 if (oldobject != srcobject) { 3439 3440 /* 3441 * Set the object optimization hint flag 3442 */ 3443 vm_object_set_flag(srcobject, OBJ_OPT); 3444 vm_object_reference(srcobject); 3445 3446 if (oldobject) { 3447 LIST_REMOVE( 3448 first_object, shadow_list); 3449 oldobject->shadow_count--; 3450 /* XXX bump generation? */ 3451 vm_object_deallocate(oldobject); 3452 } 3453 3454 LIST_INSERT_HEAD(&srcobject->shadow_head, 3455 first_object, shadow_list); 3456 srcobject->shadow_count++; 3457 /* XXX bump generation? */ 3458 3459 first_object->backing_object = srcobject; 3460 } 3461 first_object->backing_object_offset = cp; 3462 map->timestamp++; 3463 } else { 3464 pmap_remove (map->pmap, uaddr, tend); 3465 } 3466 /* 3467 * Otherwise, we have to do a logical mmap. 3468 */ 3469 } else { 3470 3471 vm_object_set_flag(srcobject, OBJ_OPT); 3472 vm_object_reference(srcobject); 3473 3474 pmap_remove (map->pmap, uaddr, tend); 3475 3476 vm_object_pmap_copy_1 (srcobject, oindex, oindex + osize); 3477 vm_map_lock_upgrade(map); 3478 3479 if (entry == &map->header) { 3480 map->first_free = &map->header; 3481 } else if (map->first_free->start >= start) { 3482 map->first_free = entry->prev; 3483 } 3484 3485 SAVE_HINT(map, entry->prev); 3486 vm_map_entry_delete(map, entry, &count); 3487 3488 object = srcobject; 3489 ooffset = cp; 3490 3491 rv = vm_map_insert(map, &count, 3492 object, ooffset, start, tend, 3493 VM_PROT_ALL, VM_PROT_ALL, MAP_COPY_ON_WRITE); 3494 3495 if (rv != KERN_SUCCESS) 3496 panic("vm_uiomove: could not insert new entry: %d", rv); 3497 } 3498 3499 /* 3500 * Map the window directly, if it is already in memory 3501 */ 3502 pmap_object_init_pt(map->pmap, uaddr, entry->protection, 3503 srcobject, oindex, tcnt, 0); 3504 3505 map->timestamp++; 3506 vm_map_unlock(map); 3507 vm_map_entry_release(count); 3508 3509 cnt -= tcnt; 3510 uaddr += tcnt; 3511 cp += tcnt; 3512 if (npages) 3513 *npages += osize; 3514 } 3515 return 0; 3516 } 3517 3518 #endif 3519 3520 /* 3521 * Performs the copy_on_write operations necessary to allow the virtual copies 3522 * into user space to work. This has to be called for write(2) system calls 3523 * from other processes, file unlinking, and file size shrinkage. 3524 */ 3525 void 3526 vm_freeze_copyopts(vm_object_t object, vm_pindex_t froma, vm_pindex_t toa) 3527 { 3528 int rv; 3529 vm_object_t robject; 3530 vm_pindex_t idx; 3531 3532 if ((object == NULL) || 3533 ((object->flags & OBJ_OPT) == 0)) 3534 return; 3535 3536 if (object->shadow_count > object->ref_count) 3537 panic("vm_freeze_copyopts: sc > rc"); 3538 3539 while ((robject = LIST_FIRST(&object->shadow_head)) != NULL) { 3540 vm_pindex_t bo_pindex; 3541 vm_page_t m_in, m_out; 3542 3543 bo_pindex = OFF_TO_IDX(robject->backing_object_offset); 3544 3545 vm_object_reference(robject); 3546 3547 vm_object_pip_wait(robject, "objfrz"); 3548 3549 if (robject->ref_count == 1) { 3550 vm_object_deallocate(robject); 3551 continue; 3552 } 3553 3554 vm_object_pip_add(robject, 1); 3555 3556 for (idx = 0; idx < robject->size; idx++) { 3557 3558 m_out = vm_page_grab(robject, idx, 3559 VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 3560 3561 if (m_out->valid == 0) { 3562 m_in = vm_page_grab(object, bo_pindex + idx, 3563 VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 3564 if (m_in->valid == 0) { 3565 rv = vm_pager_get_pages(object, &m_in, 1, 0); 3566 if (rv != VM_PAGER_OK) { 3567 printf("vm_freeze_copyopts: cannot read page from file: %lx\n", (long)m_in->pindex); 3568 continue; 3569 } 3570 vm_page_deactivate(m_in); 3571 } 3572 3573 vm_page_protect(m_in, VM_PROT_NONE); 3574 pmap_copy_page(VM_PAGE_TO_PHYS(m_in), VM_PAGE_TO_PHYS(m_out)); 3575 m_out->valid = m_in->valid; 3576 vm_page_dirty(m_out); 3577 vm_page_activate(m_out); 3578 vm_page_wakeup(m_in); 3579 } 3580 vm_page_wakeup(m_out); 3581 } 3582 3583 object->shadow_count--; 3584 object->ref_count--; 3585 LIST_REMOVE(robject, shadow_list); 3586 robject->backing_object = NULL; 3587 robject->backing_object_offset = 0; 3588 3589 vm_object_pip_wakeup(robject); 3590 vm_object_deallocate(robject); 3591 } 3592 3593 vm_object_clear_flag(object, OBJ_OPT); 3594 } 3595 3596 #include "opt_ddb.h" 3597 #ifdef DDB 3598 #include <sys/kernel.h> 3599 3600 #include <ddb/ddb.h> 3601 3602 /* 3603 * vm_map_print: [ debug ] 3604 */ 3605 DB_SHOW_COMMAND(map, vm_map_print) 3606 { 3607 static int nlines; 3608 /* XXX convert args. */ 3609 vm_map_t map = (vm_map_t)addr; 3610 boolean_t full = have_addr; 3611 3612 vm_map_entry_t entry; 3613 3614 db_iprintf("Task map %p: pmap=%p, nentries=%d, version=%u\n", 3615 (void *)map, 3616 (void *)map->pmap, map->nentries, map->timestamp); 3617 nlines++; 3618 3619 if (!full && db_indent) 3620 return; 3621 3622 db_indent += 2; 3623 for (entry = map->header.next; entry != &map->header; 3624 entry = entry->next) { 3625 db_iprintf("map entry %p: start=%p, end=%p\n", 3626 (void *)entry, (void *)entry->start, (void *)entry->end); 3627 nlines++; 3628 { 3629 static char *inheritance_name[4] = 3630 {"share", "copy", "none", "donate_copy"}; 3631 3632 db_iprintf(" prot=%x/%x/%s", 3633 entry->protection, 3634 entry->max_protection, 3635 inheritance_name[(int)(unsigned char)entry->inheritance]); 3636 if (entry->wired_count != 0) 3637 db_printf(", wired"); 3638 } 3639 if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) { 3640 /* XXX no %qd in kernel. Truncate entry->offset. */ 3641 db_printf(", share=%p, offset=0x%lx\n", 3642 (void *)entry->object.sub_map, 3643 (long)entry->offset); 3644 nlines++; 3645 if ((entry->prev == &map->header) || 3646 (entry->prev->object.sub_map != 3647 entry->object.sub_map)) { 3648 db_indent += 2; 3649 vm_map_print((db_expr_t)(intptr_t) 3650 entry->object.sub_map, 3651 full, 0, (char *)0); 3652 db_indent -= 2; 3653 } 3654 } else { 3655 /* XXX no %qd in kernel. Truncate entry->offset. */ 3656 db_printf(", object=%p, offset=0x%lx", 3657 (void *)entry->object.vm_object, 3658 (long)entry->offset); 3659 if (entry->eflags & MAP_ENTRY_COW) 3660 db_printf(", copy (%s)", 3661 (entry->eflags & MAP_ENTRY_NEEDS_COPY) ? "needed" : "done"); 3662 db_printf("\n"); 3663 nlines++; 3664 3665 if ((entry->prev == &map->header) || 3666 (entry->prev->object.vm_object != 3667 entry->object.vm_object)) { 3668 db_indent += 2; 3669 vm_object_print((db_expr_t)(intptr_t) 3670 entry->object.vm_object, 3671 full, 0, (char *)0); 3672 nlines += 4; 3673 db_indent -= 2; 3674 } 3675 } 3676 } 3677 db_indent -= 2; 3678 if (db_indent == 0) 3679 nlines = 0; 3680 } 3681 3682 3683 DB_SHOW_COMMAND(procvm, procvm) 3684 { 3685 struct proc *p; 3686 3687 if (have_addr) { 3688 p = (struct proc *) addr; 3689 } else { 3690 p = curproc; 3691 } 3692 3693 db_printf("p = %p, vmspace = %p, map = %p, pmap = %p\n", 3694 (void *)p, (void *)p->p_vmspace, (void *)&p->p_vmspace->vm_map, 3695 (void *)vmspace_pmap(p->p_vmspace)); 3696 3697 vm_map_print((db_expr_t)(intptr_t)&p->p_vmspace->vm_map, 1, 0, NULL); 3698 } 3699 3700 #endif /* DDB */ 3701