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 1.56 2007/04/29 18:25:41 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/kernel.h> 75 #include <sys/proc.h> 76 #include <sys/lock.h> 77 #include <sys/vmmeter.h> 78 #include <sys/mman.h> 79 #include <sys/vnode.h> 80 #include <sys/resourcevar.h> 81 #include <sys/shm.h> 82 #include <sys/tree.h> 83 #include <sys/malloc.h> 84 85 #include <vm/vm.h> 86 #include <vm/vm_param.h> 87 #include <vm/pmap.h> 88 #include <vm/vm_map.h> 89 #include <vm/vm_page.h> 90 #include <vm/vm_object.h> 91 #include <vm/vm_pager.h> 92 #include <vm/vm_kern.h> 93 #include <vm/vm_extern.h> 94 #include <vm/swap_pager.h> 95 #include <vm/vm_zone.h> 96 97 #include <sys/thread2.h> 98 #include <sys/sysref2.h> 99 100 /* 101 * Virtual memory maps provide for the mapping, protection, 102 * and sharing of virtual memory objects. In addition, 103 * this module provides for an efficient virtual copy of 104 * memory from one map to another. 105 * 106 * Synchronization is required prior to most operations. 107 * 108 * Maps consist of an ordered doubly-linked list of simple 109 * entries; a single hint is used to speed up lookups. 110 * 111 * Since portions of maps are specified by start/end addresses, 112 * which may not align with existing map entries, all 113 * routines merely "clip" entries to these start/end values. 114 * [That is, an entry is split into two, bordering at a 115 * start or end value.] Note that these clippings may not 116 * always be necessary (as the two resulting entries are then 117 * not changed); however, the clipping is done for convenience. 118 * 119 * As mentioned above, virtual copy operations are performed 120 * by copying VM object references from one map to 121 * another, and then marking both regions as copy-on-write. 122 */ 123 124 static void vmspace_terminate(struct vmspace *vm); 125 static void vmspace_dtor(void *obj, void *private); 126 127 MALLOC_DEFINE(M_VMSPACE, "vmspace", "vmspace objcache backingstore"); 128 129 struct sysref_class vmspace_sysref_class = { 130 .name = "vmspace", 131 .mtype = M_VMSPACE, 132 .proto = SYSREF_PROTO_VMSPACE, 133 .offset = offsetof(struct vmspace, vm_sysref), 134 .objsize = sizeof(struct vmspace), 135 .mag_capacity = 32, 136 .flags = SRC_MANAGEDINIT, 137 .dtor = vmspace_dtor, 138 .ops = { 139 .terminate = (sysref_terminate_func_t)vmspace_terminate 140 } 141 }; 142 143 #define VMEPERCPU 2 144 145 static struct vm_zone mapentzone_store, mapzone_store; 146 static vm_zone_t mapentzone, mapzone; 147 static struct vm_object mapentobj, mapobj; 148 149 static struct vm_map_entry map_entry_init[MAX_MAPENT]; 150 static struct vm_map_entry cpu_map_entry_init[MAXCPU][VMEPERCPU]; 151 static struct vm_map map_init[MAX_KMAP]; 152 153 static void vm_map_entry_shadow(vm_map_entry_t entry); 154 static vm_map_entry_t vm_map_entry_create(vm_map_t map, int *); 155 static void vm_map_entry_dispose (vm_map_t map, vm_map_entry_t entry, int *); 156 static void _vm_map_clip_end (vm_map_t, vm_map_entry_t, vm_offset_t, int *); 157 static void _vm_map_clip_start (vm_map_t, vm_map_entry_t, vm_offset_t, int *); 158 static void vm_map_entry_delete (vm_map_t, vm_map_entry_t, int *); 159 static void vm_map_entry_unwire (vm_map_t, vm_map_entry_t); 160 static void vm_map_copy_entry (vm_map_t, vm_map_t, vm_map_entry_t, 161 vm_map_entry_t); 162 static void vm_map_split (vm_map_entry_t); 163 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); 164 165 /* 166 * vm_map_startup: 167 * 168 * Initialize the vm_map module. Must be called before 169 * any other vm_map routines. 170 * 171 * Map and entry structures are allocated from the general 172 * purpose memory pool with some exceptions: 173 * 174 * - The kernel map and kmem submap are allocated statically. 175 * - Kernel map entries are allocated out of a static pool. 176 * 177 * These restrictions are necessary since malloc() uses the 178 * maps and requires map entries. 179 */ 180 void 181 vm_map_startup(void) 182 { 183 mapzone = &mapzone_store; 184 zbootinit(mapzone, "MAP", sizeof (struct vm_map), 185 map_init, MAX_KMAP); 186 mapentzone = &mapentzone_store; 187 zbootinit(mapentzone, "MAP ENTRY", sizeof (struct vm_map_entry), 188 map_entry_init, MAX_MAPENT); 189 } 190 191 /* 192 * vm_init2 - called prior to any vmspace allocations 193 */ 194 void 195 vm_init2(void) 196 { 197 zinitna(mapentzone, &mapentobj, NULL, 0, 0, 198 ZONE_USE_RESERVE | ZONE_SPECIAL, 1); 199 zinitna(mapzone, &mapobj, NULL, 0, 0, 0, 1); 200 pmap_init2(); 201 vm_object_init2(); 202 } 203 204 205 /* 206 * Red black tree functions 207 */ 208 static int rb_vm_map_compare(vm_map_entry_t a, vm_map_entry_t b); 209 RB_GENERATE(vm_map_rb_tree, vm_map_entry, rb_entry, rb_vm_map_compare); 210 211 /* a->start is address, and the only field has to be initialized */ 212 static int 213 rb_vm_map_compare(vm_map_entry_t a, vm_map_entry_t b) 214 { 215 if (a->start < b->start) 216 return(-1); 217 else if (a->start > b->start) 218 return(1); 219 return(0); 220 } 221 222 /* 223 * Allocate a vmspace structure, including a vm_map and pmap. 224 * Initialize numerous fields. While the initial allocation is zerod, 225 * subsequence reuse from the objcache leaves elements of the structure 226 * intact (particularly the pmap), so portions must be zerod. 227 * 228 * The structure is not considered activated until we call sysref_activate(). 229 */ 230 struct vmspace * 231 vmspace_alloc(vm_offset_t min, vm_offset_t max) 232 { 233 struct vmspace *vm; 234 235 vm = sysref_alloc(&vmspace_sysref_class); 236 bzero(&vm->vm_startcopy, 237 (char *)&vm->vm_endcopy - (char *)&vm->vm_startcopy); 238 vm_map_init(&vm->vm_map, min, max, NULL); 239 pmap_pinit(vmspace_pmap(vm)); /* (some fields reused) */ 240 vm->vm_map.pmap = vmspace_pmap(vm); /* XXX */ 241 vm->vm_shm = NULL; 242 vm->vm_exitingcnt = 0; 243 cpu_vmspace_alloc(vm); 244 sysref_activate(&vm->vm_sysref); 245 return (vm); 246 } 247 248 /* 249 * dtor function - Some elements of the pmap are retained in the 250 * free-cached vmspaces to improve performance. We have to clean them up 251 * here before returning the vmspace to the memory pool. 252 */ 253 static void 254 vmspace_dtor(void *obj, void *private) 255 { 256 struct vmspace *vm = obj; 257 258 pmap_puninit(vmspace_pmap(vm)); 259 } 260 261 /* 262 * Called in two cases: 263 * 264 * (1) When the last sysref is dropped, but exitingcnt might still be 265 * non-zero. 266 * 267 * (2) When there are no sysrefs (i.e. refcnt is negative) left and the 268 * exitingcnt becomes zero 269 * 270 * sysref will not scrap the object until we call sysref_put() once more 271 * after the last ref has been dropped. 272 */ 273 static void 274 vmspace_terminate(struct vmspace *vm) 275 { 276 int count; 277 278 /* 279 * If exitingcnt is non-zero we can't get rid of the entire vmspace 280 * yet, but we can scrap user memory. 281 */ 282 if (vm->vm_exitingcnt) { 283 shmexit(vm); 284 pmap_remove_pages(vmspace_pmap(vm), VM_MIN_USER_ADDRESS, 285 VM_MAX_USER_ADDRESS); 286 vm_map_remove(&vm->vm_map, VM_MIN_USER_ADDRESS, 287 VM_MAX_USER_ADDRESS); 288 289 return; 290 } 291 cpu_vmspace_free(vm); 292 293 /* 294 * Make sure any SysV shm is freed, it might not have in 295 * exit1() 296 */ 297 shmexit(vm); 298 299 KKASSERT(vm->vm_upcalls == NULL); 300 301 /* 302 * Lock the map, to wait out all other references to it. 303 * Delete all of the mappings and pages they hold, then call 304 * the pmap module to reclaim anything left. 305 */ 306 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 307 vm_map_lock(&vm->vm_map); 308 vm_map_delete(&vm->vm_map, vm->vm_map.min_offset, 309 vm->vm_map.max_offset, &count); 310 vm_map_unlock(&vm->vm_map); 311 vm_map_entry_release(count); 312 313 pmap_release(vmspace_pmap(vm)); 314 sysref_put(&vm->vm_sysref); 315 } 316 317 /* 318 * This is called in the wait*() handling code. The vmspace can be terminated 319 * after the last wait is finished using it. 320 */ 321 void 322 vmspace_exitfree(struct proc *p) 323 { 324 struct vmspace *vm; 325 326 vm = p->p_vmspace; 327 p->p_vmspace = NULL; 328 329 if (--vm->vm_exitingcnt == 0 && sysref_isinactive(&vm->vm_sysref)) 330 vmspace_terminate(vm); 331 } 332 333 /* 334 * vmspace_swap_count() 335 * 336 * Swap useage is determined by taking the proportional swap used by 337 * VM objects backing the VM map. To make up for fractional losses, 338 * if the VM object has any swap use at all the associated map entries 339 * count for at least 1 swap page. 340 */ 341 int 342 vmspace_swap_count(struct vmspace *vmspace) 343 { 344 vm_map_t map = &vmspace->vm_map; 345 vm_map_entry_t cur; 346 vm_object_t object; 347 int count = 0; 348 int n; 349 350 for (cur = map->header.next; cur != &map->header; cur = cur->next) { 351 switch(cur->maptype) { 352 case VM_MAPTYPE_NORMAL: 353 case VM_MAPTYPE_VPAGETABLE: 354 if ((object = cur->object.vm_object) == NULL) 355 break; 356 if (object->type != OBJT_SWAP) 357 break; 358 n = (cur->end - cur->start) / PAGE_SIZE; 359 if (object->un_pager.swp.swp_bcount) { 360 count += object->un_pager.swp.swp_bcount * 361 SWAP_META_PAGES * n / object->size + 1; 362 } 363 break; 364 default: 365 break; 366 } 367 } 368 return(count); 369 } 370 371 /* 372 * vmspace_anonymous_count() 373 * 374 * Calculate the approximate number of anonymous pages in use by 375 * this vmspace. To make up for fractional losses, we count each 376 * VM object as having at least 1 anonymous page. 377 */ 378 int 379 vmspace_anonymous_count(struct vmspace *vmspace) 380 { 381 vm_map_t map = &vmspace->vm_map; 382 vm_map_entry_t cur; 383 vm_object_t object; 384 int count = 0; 385 386 for (cur = map->header.next; cur != &map->header; cur = cur->next) { 387 switch(cur->maptype) { 388 case VM_MAPTYPE_NORMAL: 389 case VM_MAPTYPE_VPAGETABLE: 390 if ((object = cur->object.vm_object) == NULL) 391 break; 392 if (object->type != OBJT_DEFAULT && 393 object->type != OBJT_SWAP) { 394 break; 395 } 396 count += object->resident_page_count; 397 break; 398 default: 399 break; 400 } 401 } 402 return(count); 403 } 404 405 406 407 408 /* 409 * vm_map_create: 410 * 411 * Creates and returns a new empty VM map with 412 * the given physical map structure, and having 413 * the given lower and upper address bounds. 414 */ 415 vm_map_t 416 vm_map_create(vm_map_t result, pmap_t pmap, vm_offset_t min, vm_offset_t max) 417 { 418 if (result == NULL) 419 result = zalloc(mapzone); 420 vm_map_init(result, min, max, pmap); 421 return (result); 422 } 423 424 /* 425 * Initialize an existing vm_map structure 426 * such as that in the vmspace structure. 427 * The pmap is set elsewhere. 428 */ 429 void 430 vm_map_init(struct vm_map *map, vm_offset_t min, vm_offset_t max, pmap_t pmap) 431 { 432 map->header.next = map->header.prev = &map->header; 433 RB_INIT(&map->rb_root); 434 map->nentries = 0; 435 map->size = 0; 436 map->system_map = 0; 437 map->infork = 0; 438 map->min_offset = min; 439 map->max_offset = max; 440 map->pmap = pmap; 441 map->first_free = &map->header; 442 map->hint = &map->header; 443 map->timestamp = 0; 444 lockinit(&map->lock, "thrd_sleep", 0, 0); 445 } 446 447 /* 448 * Shadow the vm_map_entry's object. This typically needs to be done when 449 * a write fault is taken on an entry which had previously been cloned by 450 * fork(). The shared object (which might be NULL) must become private so 451 * we add a shadow layer above it. 452 * 453 * Object allocation for anonymous mappings is defered as long as possible. 454 * When creating a shadow, however, the underlying object must be instantiated 455 * so it can be shared. 456 * 457 * If the map segment is governed by a virtual page table then it is 458 * possible to address offsets beyond the mapped area. Just allocate 459 * a maximally sized object for this case. 460 */ 461 static 462 void 463 vm_map_entry_shadow(vm_map_entry_t entry) 464 { 465 if (entry->maptype == VM_MAPTYPE_VPAGETABLE) { 466 vm_object_shadow(&entry->object.vm_object, &entry->offset, 467 0x7FFFFFFF); /* XXX */ 468 } else { 469 vm_object_shadow(&entry->object.vm_object, &entry->offset, 470 atop(entry->end - entry->start)); 471 } 472 entry->eflags &= ~MAP_ENTRY_NEEDS_COPY; 473 } 474 475 /* 476 * Allocate an object for a vm_map_entry. 477 * 478 * Object allocation for anonymous mappings is defered as long as possible. 479 * This function is called when we can defer no longer, generally when a map 480 * entry might be split or forked or takes a page fault. 481 * 482 * If the map segment is governed by a virtual page table then it is 483 * possible to address offsets beyond the mapped area. Just allocate 484 * a maximally sized object for this case. 485 */ 486 void 487 vm_map_entry_allocate_object(vm_map_entry_t entry) 488 { 489 vm_object_t obj; 490 491 if (entry->maptype == VM_MAPTYPE_VPAGETABLE) { 492 obj = vm_object_allocate(OBJT_DEFAULT, 0x7FFFFFFF); /* XXX */ 493 } else { 494 obj = vm_object_allocate(OBJT_DEFAULT, 495 atop(entry->end - entry->start)); 496 } 497 entry->object.vm_object = obj; 498 entry->offset = 0; 499 } 500 501 /* 502 * vm_map_entry_reserve_cpu_init: 503 * 504 * Set an initial negative count so the first attempt to reserve 505 * space preloads a bunch of vm_map_entry's for this cpu. Also 506 * pre-allocate 2 vm_map_entries which will be needed by zalloc() to 507 * map a new page for vm_map_entry structures. SMP systems are 508 * particularly sensitive. 509 * 510 * This routine is called in early boot so we cannot just call 511 * vm_map_entry_reserve(). 512 * 513 * May be called for a gd other then mycpu, but may only be called 514 * during early boot. 515 */ 516 void 517 vm_map_entry_reserve_cpu_init(globaldata_t gd) 518 { 519 vm_map_entry_t entry; 520 int i; 521 522 gd->gd_vme_avail -= MAP_RESERVE_COUNT * 2; 523 entry = &cpu_map_entry_init[gd->gd_cpuid][0]; 524 for (i = 0; i < VMEPERCPU; ++i, ++entry) { 525 entry->next = gd->gd_vme_base; 526 gd->gd_vme_base = entry; 527 } 528 } 529 530 /* 531 * vm_map_entry_reserve: 532 * 533 * Reserves vm_map_entry structures so code later on can manipulate 534 * map_entry structures within a locked map without blocking trying 535 * to allocate a new vm_map_entry. 536 */ 537 int 538 vm_map_entry_reserve(int count) 539 { 540 struct globaldata *gd = mycpu; 541 vm_map_entry_t entry; 542 543 crit_enter(); 544 545 /* 546 * Make sure we have enough structures in gd_vme_base to handle 547 * the reservation request. 548 */ 549 while (gd->gd_vme_avail < count) { 550 entry = zalloc(mapentzone); 551 entry->next = gd->gd_vme_base; 552 gd->gd_vme_base = entry; 553 ++gd->gd_vme_avail; 554 } 555 gd->gd_vme_avail -= count; 556 crit_exit(); 557 return(count); 558 } 559 560 /* 561 * vm_map_entry_release: 562 * 563 * Releases previously reserved vm_map_entry structures that were not 564 * used. If we have too much junk in our per-cpu cache clean some of 565 * it out. 566 */ 567 void 568 vm_map_entry_release(int count) 569 { 570 struct globaldata *gd = mycpu; 571 vm_map_entry_t entry; 572 573 crit_enter(); 574 gd->gd_vme_avail += count; 575 while (gd->gd_vme_avail > MAP_RESERVE_SLOP) { 576 entry = gd->gd_vme_base; 577 KKASSERT(entry != NULL); 578 gd->gd_vme_base = entry->next; 579 --gd->gd_vme_avail; 580 crit_exit(); 581 zfree(mapentzone, entry); 582 crit_enter(); 583 } 584 crit_exit(); 585 } 586 587 /* 588 * vm_map_entry_kreserve: 589 * 590 * Reserve map entry structures for use in kernel_map itself. These 591 * entries have *ALREADY* been reserved on a per-cpu basis when the map 592 * was inited. This function is used by zalloc() to avoid a recursion 593 * when zalloc() itself needs to allocate additional kernel memory. 594 * 595 * This function works like the normal reserve but does not load the 596 * vm_map_entry cache (because that would result in an infinite 597 * recursion). Note that gd_vme_avail may go negative. This is expected. 598 * 599 * Any caller of this function must be sure to renormalize after 600 * potentially eating entries to ensure that the reserve supply 601 * remains intact. 602 */ 603 int 604 vm_map_entry_kreserve(int count) 605 { 606 struct globaldata *gd = mycpu; 607 608 crit_enter(); 609 gd->gd_vme_avail -= count; 610 crit_exit(); 611 KASSERT(gd->gd_vme_base != NULL, ("no reserved entries left, gd_vme_avail = %d\n", gd->gd_vme_avail)); 612 return(count); 613 } 614 615 /* 616 * vm_map_entry_krelease: 617 * 618 * Release previously reserved map entries for kernel_map. We do not 619 * attempt to clean up like the normal release function as this would 620 * cause an unnecessary (but probably not fatal) deep procedure call. 621 */ 622 void 623 vm_map_entry_krelease(int count) 624 { 625 struct globaldata *gd = mycpu; 626 627 crit_enter(); 628 gd->gd_vme_avail += count; 629 crit_exit(); 630 } 631 632 /* 633 * vm_map_entry_create: [ internal use only ] 634 * 635 * Allocates a VM map entry for insertion. No entry fields are filled 636 * in. 637 * 638 * This routine may be called from an interrupt thread but not a FAST 639 * interrupt. This routine may recurse the map lock. 640 */ 641 static vm_map_entry_t 642 vm_map_entry_create(vm_map_t map, int *countp) 643 { 644 struct globaldata *gd = mycpu; 645 vm_map_entry_t entry; 646 647 KKASSERT(*countp > 0); 648 --*countp; 649 crit_enter(); 650 entry = gd->gd_vme_base; 651 KASSERT(entry != NULL, ("gd_vme_base NULL! count %d", *countp)); 652 gd->gd_vme_base = entry->next; 653 crit_exit(); 654 return(entry); 655 } 656 657 /* 658 * vm_map_entry_dispose: [ internal use only ] 659 * 660 * Dispose of a vm_map_entry that is no longer being referenced. This 661 * function may be called from an interrupt. 662 */ 663 static void 664 vm_map_entry_dispose(vm_map_t map, vm_map_entry_t entry, int *countp) 665 { 666 struct globaldata *gd = mycpu; 667 668 KKASSERT(map->hint != entry); 669 KKASSERT(map->first_free != entry); 670 671 ++*countp; 672 crit_enter(); 673 entry->next = gd->gd_vme_base; 674 gd->gd_vme_base = entry; 675 crit_exit(); 676 } 677 678 679 /* 680 * vm_map_entry_{un,}link: 681 * 682 * Insert/remove entries from maps. 683 */ 684 static __inline void 685 vm_map_entry_link(vm_map_t map, 686 vm_map_entry_t after_where, 687 vm_map_entry_t entry) 688 { 689 map->nentries++; 690 entry->prev = after_where; 691 entry->next = after_where->next; 692 entry->next->prev = entry; 693 after_where->next = entry; 694 if (vm_map_rb_tree_RB_INSERT(&map->rb_root, entry)) 695 panic("vm_map_entry_link: dup addr map %p ent %p", map, entry); 696 } 697 698 static __inline void 699 vm_map_entry_unlink(vm_map_t map, 700 vm_map_entry_t entry) 701 { 702 vm_map_entry_t prev; 703 vm_map_entry_t next; 704 705 if (entry->eflags & MAP_ENTRY_IN_TRANSITION) 706 panic("vm_map_entry_unlink: attempt to mess with locked entry! %p", entry); 707 prev = entry->prev; 708 next = entry->next; 709 next->prev = prev; 710 prev->next = next; 711 vm_map_rb_tree_RB_REMOVE(&map->rb_root, entry); 712 map->nentries--; 713 } 714 715 /* 716 * vm_map_lookup_entry: [ internal use only ] 717 * 718 * Finds the map entry containing (or 719 * immediately preceding) the specified address 720 * in the given map; the entry is returned 721 * in the "entry" parameter. The boolean 722 * result indicates whether the address is 723 * actually contained in the map. 724 */ 725 boolean_t 726 vm_map_lookup_entry(vm_map_t map, vm_offset_t address, 727 vm_map_entry_t *entry /* OUT */) 728 { 729 vm_map_entry_t tmp; 730 vm_map_entry_t last; 731 732 #if 0 733 /* 734 * XXX TEMPORARILY DISABLED. For some reason our attempt to revive 735 * the hint code with the red-black lookup meets with system crashes 736 * and lockups. We do not yet know why. 737 * 738 * It is possible that the problem is related to the setting 739 * of the hint during map_entry deletion, in the code specified 740 * at the GGG comment later on in this file. 741 */ 742 /* 743 * Quickly check the cached hint, there's a good chance of a match. 744 */ 745 if (map->hint != &map->header) { 746 tmp = map->hint; 747 if (address >= tmp->start && address < tmp->end) { 748 *entry = tmp; 749 return(TRUE); 750 } 751 } 752 #endif 753 754 /* 755 * Locate the record from the top of the tree. 'last' tracks the 756 * closest prior record and is returned if no match is found, which 757 * in binary tree terms means tracking the most recent right-branch 758 * taken. If there is no prior record, &map->header is returned. 759 */ 760 last = &map->header; 761 tmp = RB_ROOT(&map->rb_root); 762 763 while (tmp) { 764 if (address >= tmp->start) { 765 if (address < tmp->end) { 766 *entry = tmp; 767 map->hint = tmp; 768 return(TRUE); 769 } 770 last = tmp; 771 tmp = RB_RIGHT(tmp, rb_entry); 772 } else { 773 tmp = RB_LEFT(tmp, rb_entry); 774 } 775 } 776 *entry = last; 777 return (FALSE); 778 } 779 780 /* 781 * vm_map_insert: 782 * 783 * Inserts the given whole VM object into the target 784 * map at the specified address range. The object's 785 * size should match that of the address range. 786 * 787 * Requires that the map be locked, and leaves it so. Requires that 788 * sufficient vm_map_entry structures have been reserved and tracks 789 * the use via countp. 790 * 791 * If object is non-NULL, ref count must be bumped by caller 792 * prior to making call to account for the new entry. 793 */ 794 int 795 vm_map_insert(vm_map_t map, int *countp, 796 vm_object_t object, vm_ooffset_t offset, 797 vm_offset_t start, vm_offset_t end, 798 vm_maptype_t maptype, 799 vm_prot_t prot, vm_prot_t max, 800 int cow) 801 { 802 vm_map_entry_t new_entry; 803 vm_map_entry_t prev_entry; 804 vm_map_entry_t temp_entry; 805 vm_eflags_t protoeflags; 806 807 /* 808 * Check that the start and end points are not bogus. 809 */ 810 811 if ((start < map->min_offset) || (end > map->max_offset) || 812 (start >= end)) 813 return (KERN_INVALID_ADDRESS); 814 815 /* 816 * Find the entry prior to the proposed starting address; if it's part 817 * of an existing entry, this range is bogus. 818 */ 819 820 if (vm_map_lookup_entry(map, start, &temp_entry)) 821 return (KERN_NO_SPACE); 822 823 prev_entry = temp_entry; 824 825 /* 826 * Assert that the next entry doesn't overlap the end point. 827 */ 828 829 if ((prev_entry->next != &map->header) && 830 (prev_entry->next->start < end)) 831 return (KERN_NO_SPACE); 832 833 protoeflags = 0; 834 835 if (cow & MAP_COPY_ON_WRITE) 836 protoeflags |= MAP_ENTRY_COW|MAP_ENTRY_NEEDS_COPY; 837 838 if (cow & MAP_NOFAULT) { 839 protoeflags |= MAP_ENTRY_NOFAULT; 840 841 KASSERT(object == NULL, 842 ("vm_map_insert: paradoxical MAP_NOFAULT request")); 843 } 844 if (cow & MAP_DISABLE_SYNCER) 845 protoeflags |= MAP_ENTRY_NOSYNC; 846 if (cow & MAP_DISABLE_COREDUMP) 847 protoeflags |= MAP_ENTRY_NOCOREDUMP; 848 849 if (object) { 850 /* 851 * When object is non-NULL, it could be shared with another 852 * process. We have to set or clear OBJ_ONEMAPPING 853 * appropriately. 854 */ 855 if ((object->ref_count > 1) || (object->shadow_count != 0)) { 856 vm_object_clear_flag(object, OBJ_ONEMAPPING); 857 } 858 } 859 else if ((prev_entry != &map->header) && 860 (prev_entry->eflags == protoeflags) && 861 (prev_entry->end == start) && 862 (prev_entry->wired_count == 0) && 863 prev_entry->maptype == maptype && 864 ((prev_entry->object.vm_object == NULL) || 865 vm_object_coalesce(prev_entry->object.vm_object, 866 OFF_TO_IDX(prev_entry->offset), 867 (vm_size_t)(prev_entry->end - prev_entry->start), 868 (vm_size_t)(end - prev_entry->end)))) { 869 /* 870 * We were able to extend the object. Determine if we 871 * can extend the previous map entry to include the 872 * new range as well. 873 */ 874 if ((prev_entry->inheritance == VM_INHERIT_DEFAULT) && 875 (prev_entry->protection == prot) && 876 (prev_entry->max_protection == max)) { 877 map->size += (end - prev_entry->end); 878 prev_entry->end = end; 879 vm_map_simplify_entry(map, prev_entry, countp); 880 return (KERN_SUCCESS); 881 } 882 883 /* 884 * If we can extend the object but cannot extend the 885 * map entry, we have to create a new map entry. We 886 * must bump the ref count on the extended object to 887 * account for it. object may be NULL. 888 */ 889 object = prev_entry->object.vm_object; 890 offset = prev_entry->offset + 891 (prev_entry->end - prev_entry->start); 892 vm_object_reference(object); 893 } 894 895 /* 896 * NOTE: if conditionals fail, object can be NULL here. This occurs 897 * in things like the buffer map where we manage kva but do not manage 898 * backing objects. 899 */ 900 901 /* 902 * Create a new entry 903 */ 904 905 new_entry = vm_map_entry_create(map, countp); 906 new_entry->start = start; 907 new_entry->end = end; 908 909 new_entry->maptype = maptype; 910 new_entry->eflags = protoeflags; 911 new_entry->object.vm_object = object; 912 new_entry->offset = offset; 913 new_entry->aux.master_pde = 0; 914 915 new_entry->inheritance = VM_INHERIT_DEFAULT; 916 new_entry->protection = prot; 917 new_entry->max_protection = max; 918 new_entry->wired_count = 0; 919 920 /* 921 * Insert the new entry into the list 922 */ 923 924 vm_map_entry_link(map, prev_entry, new_entry); 925 map->size += new_entry->end - new_entry->start; 926 927 /* 928 * Update the free space hint 929 */ 930 if ((map->first_free == prev_entry) && 931 (prev_entry->end >= new_entry->start)) { 932 map->first_free = new_entry; 933 } 934 935 #if 0 936 /* 937 * Temporarily removed to avoid MAP_STACK panic, due to 938 * MAP_STACK being a huge hack. Will be added back in 939 * when MAP_STACK (and the user stack mapping) is fixed. 940 */ 941 /* 942 * It may be possible to simplify the entry 943 */ 944 vm_map_simplify_entry(map, new_entry, countp); 945 #endif 946 947 /* 948 * Try to pre-populate the page table. Mappings governed by virtual 949 * page tables cannot be prepopulated without a lot of work, so 950 * don't try. 951 */ 952 if ((cow & (MAP_PREFAULT|MAP_PREFAULT_PARTIAL)) && 953 maptype != VM_MAPTYPE_VPAGETABLE) { 954 pmap_object_init_pt(map->pmap, start, prot, 955 object, OFF_TO_IDX(offset), end - start, 956 cow & MAP_PREFAULT_PARTIAL); 957 } 958 959 return (KERN_SUCCESS); 960 } 961 962 /* 963 * Find sufficient space for `length' bytes in the given map, starting at 964 * `start'. The map must be locked. Returns 0 on success, 1 on no space. 965 * 966 * This function will returned an arbitrarily aligned pointer. If no 967 * particular alignment is required you should pass align as 1. Note that 968 * the map may return PAGE_SIZE aligned pointers if all the lengths used in 969 * the map are a multiple of PAGE_SIZE, even if you pass a smaller align 970 * argument. 971 * 972 * 'align' should be a power of 2 but is not required to be. 973 */ 974 int 975 vm_map_findspace( 976 vm_map_t map, 977 vm_offset_t start, 978 vm_size_t length, 979 vm_offset_t align, 980 vm_offset_t *addr) 981 { 982 vm_map_entry_t entry, next; 983 vm_offset_t end; 984 vm_offset_t align_mask; 985 986 if (start < map->min_offset) 987 start = map->min_offset; 988 if (start > map->max_offset) 989 return (1); 990 991 /* 992 * If the alignment is not a power of 2 we will have to use 993 * a mod/division, set align_mask to a special value. 994 */ 995 if ((align | (align - 1)) + 1 != (align << 1)) 996 align_mask = (vm_offset_t)-1; 997 else 998 align_mask = align - 1; 999 1000 retry: 1001 /* 1002 * Look for the first possible address; if there's already something 1003 * at this address, we have to start after it. 1004 */ 1005 if (start == map->min_offset) { 1006 if ((entry = map->first_free) != &map->header) 1007 start = entry->end; 1008 } else { 1009 vm_map_entry_t tmp; 1010 1011 if (vm_map_lookup_entry(map, start, &tmp)) 1012 start = tmp->end; 1013 entry = tmp; 1014 } 1015 1016 /* 1017 * Look through the rest of the map, trying to fit a new region in the 1018 * gap between existing regions, or after the very last region. 1019 */ 1020 for (;; start = (entry = next)->end) { 1021 /* 1022 * Adjust the proposed start by the requested alignment, 1023 * be sure that we didn't wrap the address. 1024 */ 1025 if (align_mask == (vm_offset_t)-1) 1026 end = ((start + align - 1) / align) * align; 1027 else 1028 end = (start + align_mask) & ~align_mask; 1029 if (end < start) 1030 return (1); 1031 start = end; 1032 /* 1033 * Find the end of the proposed new region. Be sure we didn't 1034 * go beyond the end of the map, or wrap around the address. 1035 * Then check to see if this is the last entry or if the 1036 * proposed end fits in the gap between this and the next 1037 * entry. 1038 */ 1039 end = start + length; 1040 if (end > map->max_offset || end < start) 1041 return (1); 1042 next = entry->next; 1043 if (next == &map->header || next->start >= end) 1044 break; 1045 } 1046 map->hint = entry; 1047 if (map == &kernel_map) { 1048 vm_offset_t ksize; 1049 if ((ksize = round_page(start + length)) > kernel_vm_end) { 1050 pmap_growkernel(ksize); 1051 goto retry; 1052 } 1053 } 1054 *addr = start; 1055 return (0); 1056 } 1057 1058 /* 1059 * vm_map_find finds an unallocated region in the target address 1060 * map with the given length. The search is defined to be 1061 * first-fit from the specified address; the region found is 1062 * returned in the same parameter. 1063 * 1064 * If object is non-NULL, ref count must be bumped by caller 1065 * prior to making call to account for the new entry. 1066 */ 1067 int 1068 vm_map_find(vm_map_t map, vm_object_t object, vm_ooffset_t offset, 1069 vm_offset_t *addr, vm_size_t length, 1070 boolean_t find_space, 1071 vm_maptype_t maptype, 1072 vm_prot_t prot, vm_prot_t max, 1073 int cow) 1074 { 1075 vm_offset_t start; 1076 int result; 1077 int count; 1078 1079 start = *addr; 1080 1081 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 1082 vm_map_lock(map); 1083 if (find_space) { 1084 if (vm_map_findspace(map, start, length, 1, addr)) { 1085 vm_map_unlock(map); 1086 vm_map_entry_release(count); 1087 return (KERN_NO_SPACE); 1088 } 1089 start = *addr; 1090 } 1091 result = vm_map_insert(map, &count, object, offset, 1092 start, start + length, 1093 maptype, 1094 prot, max, 1095 cow); 1096 vm_map_unlock(map); 1097 vm_map_entry_release(count); 1098 1099 return (result); 1100 } 1101 1102 /* 1103 * vm_map_simplify_entry: 1104 * 1105 * Simplify the given map entry by merging with either neighbor. This 1106 * routine also has the ability to merge with both neighbors. 1107 * 1108 * The map must be locked. 1109 * 1110 * This routine guarentees that the passed entry remains valid (though 1111 * possibly extended). When merging, this routine may delete one or 1112 * both neighbors. No action is taken on entries which have their 1113 * in-transition flag set. 1114 */ 1115 void 1116 vm_map_simplify_entry(vm_map_t map, vm_map_entry_t entry, int *countp) 1117 { 1118 vm_map_entry_t next, prev; 1119 vm_size_t prevsize, esize; 1120 1121 if (entry->eflags & MAP_ENTRY_IN_TRANSITION) { 1122 ++mycpu->gd_cnt.v_intrans_coll; 1123 return; 1124 } 1125 1126 if (entry->maptype == VM_MAPTYPE_SUBMAP) 1127 return; 1128 1129 prev = entry->prev; 1130 if (prev != &map->header) { 1131 prevsize = prev->end - prev->start; 1132 if ( (prev->end == entry->start) && 1133 (prev->maptype == entry->maptype) && 1134 (prev->object.vm_object == entry->object.vm_object) && 1135 (!prev->object.vm_object || 1136 (prev->offset + prevsize == entry->offset)) && 1137 (prev->eflags == entry->eflags) && 1138 (prev->protection == entry->protection) && 1139 (prev->max_protection == entry->max_protection) && 1140 (prev->inheritance == entry->inheritance) && 1141 (prev->wired_count == entry->wired_count)) { 1142 if (map->first_free == prev) 1143 map->first_free = entry; 1144 if (map->hint == prev) 1145 map->hint = entry; 1146 vm_map_entry_unlink(map, prev); 1147 entry->start = prev->start; 1148 entry->offset = prev->offset; 1149 if (prev->object.vm_object) 1150 vm_object_deallocate(prev->object.vm_object); 1151 vm_map_entry_dispose(map, prev, countp); 1152 } 1153 } 1154 1155 next = entry->next; 1156 if (next != &map->header) { 1157 esize = entry->end - entry->start; 1158 if ((entry->end == next->start) && 1159 (next->maptype == entry->maptype) && 1160 (next->object.vm_object == entry->object.vm_object) && 1161 (!entry->object.vm_object || 1162 (entry->offset + esize == next->offset)) && 1163 (next->eflags == entry->eflags) && 1164 (next->protection == entry->protection) && 1165 (next->max_protection == entry->max_protection) && 1166 (next->inheritance == entry->inheritance) && 1167 (next->wired_count == entry->wired_count)) { 1168 if (map->first_free == next) 1169 map->first_free = entry; 1170 if (map->hint == next) 1171 map->hint = entry; 1172 vm_map_entry_unlink(map, next); 1173 entry->end = next->end; 1174 if (next->object.vm_object) 1175 vm_object_deallocate(next->object.vm_object); 1176 vm_map_entry_dispose(map, next, countp); 1177 } 1178 } 1179 } 1180 /* 1181 * vm_map_clip_start: [ internal use only ] 1182 * 1183 * Asserts that the given entry begins at or after 1184 * the specified address; if necessary, 1185 * it splits the entry into two. 1186 */ 1187 #define vm_map_clip_start(map, entry, startaddr, countp) \ 1188 { \ 1189 if (startaddr > entry->start) \ 1190 _vm_map_clip_start(map, entry, startaddr, countp); \ 1191 } 1192 1193 /* 1194 * This routine is called only when it is known that 1195 * the entry must be split. 1196 */ 1197 static void 1198 _vm_map_clip_start(vm_map_t map, vm_map_entry_t entry, vm_offset_t start, int *countp) 1199 { 1200 vm_map_entry_t new_entry; 1201 1202 /* 1203 * Split off the front portion -- note that we must insert the new 1204 * entry BEFORE this one, so that this entry has the specified 1205 * starting address. 1206 */ 1207 1208 vm_map_simplify_entry(map, entry, countp); 1209 1210 /* 1211 * If there is no object backing this entry, we might as well create 1212 * one now. If we defer it, an object can get created after the map 1213 * is clipped, and individual objects will be created for the split-up 1214 * map. This is a bit of a hack, but is also about the best place to 1215 * put this improvement. 1216 */ 1217 if (entry->object.vm_object == NULL && !map->system_map) { 1218 vm_map_entry_allocate_object(entry); 1219 } 1220 1221 new_entry = vm_map_entry_create(map, countp); 1222 *new_entry = *entry; 1223 1224 new_entry->end = start; 1225 entry->offset += (start - entry->start); 1226 entry->start = start; 1227 1228 vm_map_entry_link(map, entry->prev, new_entry); 1229 1230 switch(entry->maptype) { 1231 case VM_MAPTYPE_NORMAL: 1232 case VM_MAPTYPE_VPAGETABLE: 1233 vm_object_reference(new_entry->object.vm_object); 1234 break; 1235 default: 1236 break; 1237 } 1238 } 1239 1240 /* 1241 * vm_map_clip_end: [ internal use only ] 1242 * 1243 * Asserts that the given entry ends at or before 1244 * the specified address; if necessary, 1245 * it splits the entry into two. 1246 */ 1247 1248 #define vm_map_clip_end(map, entry, endaddr, countp) \ 1249 { \ 1250 if (endaddr < entry->end) \ 1251 _vm_map_clip_end(map, entry, endaddr, countp); \ 1252 } 1253 1254 /* 1255 * This routine is called only when it is known that 1256 * the entry must be split. 1257 */ 1258 static void 1259 _vm_map_clip_end(vm_map_t map, vm_map_entry_t entry, vm_offset_t end, int *countp) 1260 { 1261 vm_map_entry_t new_entry; 1262 1263 /* 1264 * If there is no object backing this entry, we might as well create 1265 * one now. If we defer it, an object can get created after the map 1266 * is clipped, and individual objects will be created for the split-up 1267 * map. This is a bit of a hack, but is also about the best place to 1268 * put this improvement. 1269 */ 1270 1271 if (entry->object.vm_object == NULL && !map->system_map) { 1272 vm_map_entry_allocate_object(entry); 1273 } 1274 1275 /* 1276 * Create a new entry and insert it AFTER the specified entry 1277 */ 1278 1279 new_entry = vm_map_entry_create(map, countp); 1280 *new_entry = *entry; 1281 1282 new_entry->start = entry->end = end; 1283 new_entry->offset += (end - entry->start); 1284 1285 vm_map_entry_link(map, entry, new_entry); 1286 1287 switch(entry->maptype) { 1288 case VM_MAPTYPE_NORMAL: 1289 case VM_MAPTYPE_VPAGETABLE: 1290 vm_object_reference(new_entry->object.vm_object); 1291 break; 1292 default: 1293 break; 1294 } 1295 } 1296 1297 /* 1298 * VM_MAP_RANGE_CHECK: [ internal use only ] 1299 * 1300 * Asserts that the starting and ending region 1301 * addresses fall within the valid range of the map. 1302 */ 1303 #define VM_MAP_RANGE_CHECK(map, start, end) \ 1304 { \ 1305 if (start < vm_map_min(map)) \ 1306 start = vm_map_min(map); \ 1307 if (end > vm_map_max(map)) \ 1308 end = vm_map_max(map); \ 1309 if (start > end) \ 1310 start = end; \ 1311 } 1312 1313 /* 1314 * vm_map_transition_wait: [ kernel use only ] 1315 * 1316 * Used to block when an in-transition collison occurs. The map 1317 * is unlocked for the sleep and relocked before the return. 1318 */ 1319 static 1320 void 1321 vm_map_transition_wait(vm_map_t map) 1322 { 1323 vm_map_unlock(map); 1324 tsleep(map, 0, "vment", 0); 1325 vm_map_lock(map); 1326 } 1327 1328 /* 1329 * CLIP_CHECK_BACK 1330 * CLIP_CHECK_FWD 1331 * 1332 * When we do blocking operations with the map lock held it is 1333 * possible that a clip might have occured on our in-transit entry, 1334 * requiring an adjustment to the entry in our loop. These macros 1335 * help the pageable and clip_range code deal with the case. The 1336 * conditional costs virtually nothing if no clipping has occured. 1337 */ 1338 1339 #define CLIP_CHECK_BACK(entry, save_start) \ 1340 do { \ 1341 while (entry->start != save_start) { \ 1342 entry = entry->prev; \ 1343 KASSERT(entry != &map->header, ("bad entry clip")); \ 1344 } \ 1345 } while(0) 1346 1347 #define CLIP_CHECK_FWD(entry, save_end) \ 1348 do { \ 1349 while (entry->end != save_end) { \ 1350 entry = entry->next; \ 1351 KASSERT(entry != &map->header, ("bad entry clip")); \ 1352 } \ 1353 } while(0) 1354 1355 1356 /* 1357 * vm_map_clip_range: [ kernel use only ] 1358 * 1359 * Clip the specified range and return the base entry. The 1360 * range may cover several entries starting at the returned base 1361 * and the first and last entry in the covering sequence will be 1362 * properly clipped to the requested start and end address. 1363 * 1364 * If no holes are allowed you should pass the MAP_CLIP_NO_HOLES 1365 * flag. 1366 * 1367 * The MAP_ENTRY_IN_TRANSITION flag will be set for the entries 1368 * covered by the requested range. 1369 * 1370 * The map must be exclusively locked on entry and will remain locked 1371 * on return. If no range exists or the range contains holes and you 1372 * specified that no holes were allowed, NULL will be returned. This 1373 * routine may temporarily unlock the map in order avoid a deadlock when 1374 * sleeping. 1375 */ 1376 static 1377 vm_map_entry_t 1378 vm_map_clip_range(vm_map_t map, vm_offset_t start, vm_offset_t end, 1379 int *countp, int flags) 1380 { 1381 vm_map_entry_t start_entry; 1382 vm_map_entry_t entry; 1383 1384 /* 1385 * Locate the entry and effect initial clipping. The in-transition 1386 * case does not occur very often so do not try to optimize it. 1387 */ 1388 again: 1389 if (vm_map_lookup_entry(map, start, &start_entry) == FALSE) 1390 return (NULL); 1391 entry = start_entry; 1392 if (entry->eflags & MAP_ENTRY_IN_TRANSITION) { 1393 entry->eflags |= MAP_ENTRY_NEEDS_WAKEUP; 1394 ++mycpu->gd_cnt.v_intrans_coll; 1395 ++mycpu->gd_cnt.v_intrans_wait; 1396 vm_map_transition_wait(map); 1397 /* 1398 * entry and/or start_entry may have been clipped while 1399 * we slept, or may have gone away entirely. We have 1400 * to restart from the lookup. 1401 */ 1402 goto again; 1403 } 1404 /* 1405 * Since we hold an exclusive map lock we do not have to restart 1406 * after clipping, even though clipping may block in zalloc. 1407 */ 1408 vm_map_clip_start(map, entry, start, countp); 1409 vm_map_clip_end(map, entry, end, countp); 1410 entry->eflags |= MAP_ENTRY_IN_TRANSITION; 1411 1412 /* 1413 * Scan entries covered by the range. When working on the next 1414 * entry a restart need only re-loop on the current entry which 1415 * we have already locked, since 'next' may have changed. Also, 1416 * even though entry is safe, it may have been clipped so we 1417 * have to iterate forwards through the clip after sleeping. 1418 */ 1419 while (entry->next != &map->header && entry->next->start < end) { 1420 vm_map_entry_t next = entry->next; 1421 1422 if (flags & MAP_CLIP_NO_HOLES) { 1423 if (next->start > entry->end) { 1424 vm_map_unclip_range(map, start_entry, 1425 start, entry->end, countp, flags); 1426 return(NULL); 1427 } 1428 } 1429 1430 if (next->eflags & MAP_ENTRY_IN_TRANSITION) { 1431 vm_offset_t save_end = entry->end; 1432 next->eflags |= MAP_ENTRY_NEEDS_WAKEUP; 1433 ++mycpu->gd_cnt.v_intrans_coll; 1434 ++mycpu->gd_cnt.v_intrans_wait; 1435 vm_map_transition_wait(map); 1436 1437 /* 1438 * clips might have occured while we blocked. 1439 */ 1440 CLIP_CHECK_FWD(entry, save_end); 1441 CLIP_CHECK_BACK(start_entry, start); 1442 continue; 1443 } 1444 /* 1445 * No restart necessary even though clip_end may block, we 1446 * are holding the map lock. 1447 */ 1448 vm_map_clip_end(map, next, end, countp); 1449 next->eflags |= MAP_ENTRY_IN_TRANSITION; 1450 entry = next; 1451 } 1452 if (flags & MAP_CLIP_NO_HOLES) { 1453 if (entry->end != end) { 1454 vm_map_unclip_range(map, start_entry, 1455 start, entry->end, countp, flags); 1456 return(NULL); 1457 } 1458 } 1459 return(start_entry); 1460 } 1461 1462 /* 1463 * vm_map_unclip_range: [ kernel use only ] 1464 * 1465 * Undo the effect of vm_map_clip_range(). You should pass the same 1466 * flags and the same range that you passed to vm_map_clip_range(). 1467 * This code will clear the in-transition flag on the entries and 1468 * wake up anyone waiting. This code will also simplify the sequence 1469 * and attempt to merge it with entries before and after the sequence. 1470 * 1471 * The map must be locked on entry and will remain locked on return. 1472 * 1473 * Note that you should also pass the start_entry returned by 1474 * vm_map_clip_range(). However, if you block between the two calls 1475 * with the map unlocked please be aware that the start_entry may 1476 * have been clipped and you may need to scan it backwards to find 1477 * the entry corresponding with the original start address. You are 1478 * responsible for this, vm_map_unclip_range() expects the correct 1479 * start_entry to be passed to it and will KASSERT otherwise. 1480 */ 1481 static 1482 void 1483 vm_map_unclip_range( 1484 vm_map_t map, 1485 vm_map_entry_t start_entry, 1486 vm_offset_t start, 1487 vm_offset_t end, 1488 int *countp, 1489 int flags) 1490 { 1491 vm_map_entry_t entry; 1492 1493 entry = start_entry; 1494 1495 KASSERT(entry->start == start, ("unclip_range: illegal base entry")); 1496 while (entry != &map->header && entry->start < end) { 1497 KASSERT(entry->eflags & MAP_ENTRY_IN_TRANSITION, ("in-transition flag not set during unclip on: %p", entry)); 1498 KASSERT(entry->end <= end, ("unclip_range: tail wasn't clipped")); 1499 entry->eflags &= ~MAP_ENTRY_IN_TRANSITION; 1500 if (entry->eflags & MAP_ENTRY_NEEDS_WAKEUP) { 1501 entry->eflags &= ~MAP_ENTRY_NEEDS_WAKEUP; 1502 wakeup(map); 1503 } 1504 entry = entry->next; 1505 } 1506 1507 /* 1508 * Simplification does not block so there is no restart case. 1509 */ 1510 entry = start_entry; 1511 while (entry != &map->header && entry->start < end) { 1512 vm_map_simplify_entry(map, entry, countp); 1513 entry = entry->next; 1514 } 1515 } 1516 1517 /* 1518 * vm_map_submap: [ kernel use only ] 1519 * 1520 * Mark the given range as handled by a subordinate map. 1521 * 1522 * This range must have been created with vm_map_find, 1523 * and no other operations may have been performed on this 1524 * range prior to calling vm_map_submap. 1525 * 1526 * Only a limited number of operations can be performed 1527 * within this rage after calling vm_map_submap: 1528 * vm_fault 1529 * [Don't try vm_map_copy!] 1530 * 1531 * To remove a submapping, one must first remove the 1532 * range from the superior map, and then destroy the 1533 * submap (if desired). [Better yet, don't try it.] 1534 */ 1535 int 1536 vm_map_submap(vm_map_t map, vm_offset_t start, vm_offset_t end, vm_map_t submap) 1537 { 1538 vm_map_entry_t entry; 1539 int result = KERN_INVALID_ARGUMENT; 1540 int count; 1541 1542 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 1543 vm_map_lock(map); 1544 1545 VM_MAP_RANGE_CHECK(map, start, end); 1546 1547 if (vm_map_lookup_entry(map, start, &entry)) { 1548 vm_map_clip_start(map, entry, start, &count); 1549 } else { 1550 entry = entry->next; 1551 } 1552 1553 vm_map_clip_end(map, entry, end, &count); 1554 1555 if ((entry->start == start) && (entry->end == end) && 1556 ((entry->eflags & MAP_ENTRY_COW) == 0) && 1557 (entry->object.vm_object == NULL)) { 1558 entry->object.sub_map = submap; 1559 entry->maptype = VM_MAPTYPE_SUBMAP; 1560 result = KERN_SUCCESS; 1561 } 1562 vm_map_unlock(map); 1563 vm_map_entry_release(count); 1564 1565 return (result); 1566 } 1567 1568 /* 1569 * vm_map_protect: 1570 * 1571 * Sets the protection of the specified address region in the target map. 1572 * If "set_max" is specified, the maximum protection is to be set; 1573 * otherwise, only the current protection is affected. 1574 * 1575 * The protection is not applicable to submaps, but is applicable to normal 1576 * maps and maps governed by virtual page tables. For example, when operating 1577 * on a virtual page table our protection basically controls how COW occurs 1578 * on the backing object, whereas the virtual page table abstraction itself 1579 * is an abstraction for userland. 1580 */ 1581 int 1582 vm_map_protect(vm_map_t map, vm_offset_t start, vm_offset_t end, 1583 vm_prot_t new_prot, boolean_t set_max) 1584 { 1585 vm_map_entry_t current; 1586 vm_map_entry_t entry; 1587 int count; 1588 1589 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 1590 vm_map_lock(map); 1591 1592 VM_MAP_RANGE_CHECK(map, start, end); 1593 1594 if (vm_map_lookup_entry(map, start, &entry)) { 1595 vm_map_clip_start(map, entry, start, &count); 1596 } else { 1597 entry = entry->next; 1598 } 1599 1600 /* 1601 * Make a first pass to check for protection violations. 1602 */ 1603 current = entry; 1604 while ((current != &map->header) && (current->start < end)) { 1605 if (current->maptype == VM_MAPTYPE_SUBMAP) { 1606 vm_map_unlock(map); 1607 vm_map_entry_release(count); 1608 return (KERN_INVALID_ARGUMENT); 1609 } 1610 if ((new_prot & current->max_protection) != new_prot) { 1611 vm_map_unlock(map); 1612 vm_map_entry_release(count); 1613 return (KERN_PROTECTION_FAILURE); 1614 } 1615 current = current->next; 1616 } 1617 1618 /* 1619 * Go back and fix up protections. [Note that clipping is not 1620 * necessary the second time.] 1621 */ 1622 current = entry; 1623 1624 while ((current != &map->header) && (current->start < end)) { 1625 vm_prot_t old_prot; 1626 1627 vm_map_clip_end(map, current, end, &count); 1628 1629 old_prot = current->protection; 1630 if (set_max) { 1631 current->protection = 1632 (current->max_protection = new_prot) & 1633 old_prot; 1634 } else { 1635 current->protection = new_prot; 1636 } 1637 1638 /* 1639 * Update physical map if necessary. Worry about copy-on-write 1640 * here -- CHECK THIS XXX 1641 */ 1642 1643 if (current->protection != old_prot) { 1644 #define MASK(entry) (((entry)->eflags & MAP_ENTRY_COW) ? ~VM_PROT_WRITE : \ 1645 VM_PROT_ALL) 1646 1647 pmap_protect(map->pmap, current->start, 1648 current->end, 1649 current->protection & MASK(current)); 1650 #undef MASK 1651 } 1652 1653 vm_map_simplify_entry(map, current, &count); 1654 1655 current = current->next; 1656 } 1657 1658 vm_map_unlock(map); 1659 vm_map_entry_release(count); 1660 return (KERN_SUCCESS); 1661 } 1662 1663 /* 1664 * vm_map_madvise: 1665 * 1666 * This routine traverses a processes map handling the madvise 1667 * system call. Advisories are classified as either those effecting 1668 * the vm_map_entry structure, or those effecting the underlying 1669 * objects. 1670 * 1671 * The <value> argument is used for extended madvise calls. 1672 */ 1673 int 1674 vm_map_madvise(vm_map_t map, vm_offset_t start, vm_offset_t end, 1675 int behav, off_t value) 1676 { 1677 vm_map_entry_t current, entry; 1678 int modify_map = 0; 1679 int error = 0; 1680 int count; 1681 1682 /* 1683 * Some madvise calls directly modify the vm_map_entry, in which case 1684 * we need to use an exclusive lock on the map and we need to perform 1685 * various clipping operations. Otherwise we only need a read-lock 1686 * on the map. 1687 */ 1688 1689 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 1690 1691 switch(behav) { 1692 case MADV_NORMAL: 1693 case MADV_SEQUENTIAL: 1694 case MADV_RANDOM: 1695 case MADV_NOSYNC: 1696 case MADV_AUTOSYNC: 1697 case MADV_NOCORE: 1698 case MADV_CORE: 1699 case MADV_SETMAP: 1700 case MADV_INVAL: 1701 modify_map = 1; 1702 vm_map_lock(map); 1703 break; 1704 case MADV_WILLNEED: 1705 case MADV_DONTNEED: 1706 case MADV_FREE: 1707 vm_map_lock_read(map); 1708 break; 1709 default: 1710 vm_map_entry_release(count); 1711 return (EINVAL); 1712 } 1713 1714 /* 1715 * Locate starting entry and clip if necessary. 1716 */ 1717 1718 VM_MAP_RANGE_CHECK(map, start, end); 1719 1720 if (vm_map_lookup_entry(map, start, &entry)) { 1721 if (modify_map) 1722 vm_map_clip_start(map, entry, start, &count); 1723 } else { 1724 entry = entry->next; 1725 } 1726 1727 if (modify_map) { 1728 /* 1729 * madvise behaviors that are implemented in the vm_map_entry. 1730 * 1731 * We clip the vm_map_entry so that behavioral changes are 1732 * limited to the specified address range. 1733 */ 1734 for (current = entry; 1735 (current != &map->header) && (current->start < end); 1736 current = current->next 1737 ) { 1738 if (current->maptype == VM_MAPTYPE_SUBMAP) 1739 continue; 1740 1741 vm_map_clip_end(map, current, end, &count); 1742 1743 switch (behav) { 1744 case MADV_NORMAL: 1745 vm_map_entry_set_behavior(current, MAP_ENTRY_BEHAV_NORMAL); 1746 break; 1747 case MADV_SEQUENTIAL: 1748 vm_map_entry_set_behavior(current, MAP_ENTRY_BEHAV_SEQUENTIAL); 1749 break; 1750 case MADV_RANDOM: 1751 vm_map_entry_set_behavior(current, MAP_ENTRY_BEHAV_RANDOM); 1752 break; 1753 case MADV_NOSYNC: 1754 current->eflags |= MAP_ENTRY_NOSYNC; 1755 break; 1756 case MADV_AUTOSYNC: 1757 current->eflags &= ~MAP_ENTRY_NOSYNC; 1758 break; 1759 case MADV_NOCORE: 1760 current->eflags |= MAP_ENTRY_NOCOREDUMP; 1761 break; 1762 case MADV_CORE: 1763 current->eflags &= ~MAP_ENTRY_NOCOREDUMP; 1764 break; 1765 case MADV_INVAL: 1766 /* 1767 * Invalidate the related pmap entries, used 1768 * to flush portions of the real kernel's 1769 * pmap when the caller has removed or 1770 * modified existing mappings in a virtual 1771 * page table. 1772 */ 1773 pmap_remove(map->pmap, 1774 current->start, current->end); 1775 break; 1776 case MADV_SETMAP: 1777 /* 1778 * Set the page directory page for a map 1779 * governed by a virtual page table. Mark 1780 * the entry as being governed by a virtual 1781 * page table if it is not. 1782 * 1783 * XXX the page directory page is stored 1784 * in the avail_ssize field if the map_entry. 1785 * 1786 * XXX the map simplification code does not 1787 * compare this field so weird things may 1788 * happen if you do not apply this function 1789 * to the entire mapping governed by the 1790 * virtual page table. 1791 */ 1792 if (current->maptype != VM_MAPTYPE_VPAGETABLE) { 1793 error = EINVAL; 1794 break; 1795 } 1796 current->aux.master_pde = value; 1797 pmap_remove(map->pmap, 1798 current->start, current->end); 1799 break; 1800 default: 1801 error = EINVAL; 1802 break; 1803 } 1804 vm_map_simplify_entry(map, current, &count); 1805 } 1806 vm_map_unlock(map); 1807 } else { 1808 vm_pindex_t pindex; 1809 int count; 1810 1811 /* 1812 * madvise behaviors that are implemented in the underlying 1813 * vm_object. 1814 * 1815 * Since we don't clip the vm_map_entry, we have to clip 1816 * the vm_object pindex and count. 1817 * 1818 * NOTE! We currently do not support these functions on 1819 * virtual page tables. 1820 */ 1821 for (current = entry; 1822 (current != &map->header) && (current->start < end); 1823 current = current->next 1824 ) { 1825 vm_offset_t useStart; 1826 1827 if (current->maptype != VM_MAPTYPE_NORMAL) 1828 continue; 1829 1830 pindex = OFF_TO_IDX(current->offset); 1831 count = atop(current->end - current->start); 1832 useStart = current->start; 1833 1834 if (current->start < start) { 1835 pindex += atop(start - current->start); 1836 count -= atop(start - current->start); 1837 useStart = start; 1838 } 1839 if (current->end > end) 1840 count -= atop(current->end - end); 1841 1842 if (count <= 0) 1843 continue; 1844 1845 vm_object_madvise(current->object.vm_object, 1846 pindex, count, behav); 1847 1848 /* 1849 * Try to populate the page table. Mappings governed 1850 * by virtual page tables cannot be pre-populated 1851 * without a lot of work so don't try. 1852 */ 1853 if (behav == MADV_WILLNEED && 1854 current->maptype != VM_MAPTYPE_VPAGETABLE) { 1855 pmap_object_init_pt( 1856 map->pmap, 1857 useStart, 1858 current->protection, 1859 current->object.vm_object, 1860 pindex, 1861 (count << PAGE_SHIFT), 1862 MAP_PREFAULT_MADVISE 1863 ); 1864 } 1865 } 1866 vm_map_unlock_read(map); 1867 } 1868 vm_map_entry_release(count); 1869 return(error); 1870 } 1871 1872 1873 /* 1874 * vm_map_inherit: 1875 * 1876 * Sets the inheritance of the specified address 1877 * range in the target map. Inheritance 1878 * affects how the map will be shared with 1879 * child maps at the time of vm_map_fork. 1880 */ 1881 int 1882 vm_map_inherit(vm_map_t map, vm_offset_t start, vm_offset_t end, 1883 vm_inherit_t new_inheritance) 1884 { 1885 vm_map_entry_t entry; 1886 vm_map_entry_t temp_entry; 1887 int count; 1888 1889 switch (new_inheritance) { 1890 case VM_INHERIT_NONE: 1891 case VM_INHERIT_COPY: 1892 case VM_INHERIT_SHARE: 1893 break; 1894 default: 1895 return (KERN_INVALID_ARGUMENT); 1896 } 1897 1898 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 1899 vm_map_lock(map); 1900 1901 VM_MAP_RANGE_CHECK(map, start, end); 1902 1903 if (vm_map_lookup_entry(map, start, &temp_entry)) { 1904 entry = temp_entry; 1905 vm_map_clip_start(map, entry, start, &count); 1906 } else 1907 entry = temp_entry->next; 1908 1909 while ((entry != &map->header) && (entry->start < end)) { 1910 vm_map_clip_end(map, entry, end, &count); 1911 1912 entry->inheritance = new_inheritance; 1913 1914 vm_map_simplify_entry(map, entry, &count); 1915 1916 entry = entry->next; 1917 } 1918 vm_map_unlock(map); 1919 vm_map_entry_release(count); 1920 return (KERN_SUCCESS); 1921 } 1922 1923 /* 1924 * Implement the semantics of mlock 1925 */ 1926 int 1927 vm_map_unwire(vm_map_t map, vm_offset_t start, vm_offset_t real_end, 1928 boolean_t new_pageable) 1929 { 1930 vm_map_entry_t entry; 1931 vm_map_entry_t start_entry; 1932 vm_offset_t end; 1933 int rv = KERN_SUCCESS; 1934 int count; 1935 1936 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 1937 vm_map_lock(map); 1938 VM_MAP_RANGE_CHECK(map, start, real_end); 1939 end = real_end; 1940 1941 start_entry = vm_map_clip_range(map, start, end, &count, MAP_CLIP_NO_HOLES); 1942 if (start_entry == NULL) { 1943 vm_map_unlock(map); 1944 vm_map_entry_release(count); 1945 return (KERN_INVALID_ADDRESS); 1946 } 1947 1948 if (new_pageable == 0) { 1949 entry = start_entry; 1950 while ((entry != &map->header) && (entry->start < end)) { 1951 vm_offset_t save_start; 1952 vm_offset_t save_end; 1953 1954 /* 1955 * Already user wired or hard wired (trivial cases) 1956 */ 1957 if (entry->eflags & MAP_ENTRY_USER_WIRED) { 1958 entry = entry->next; 1959 continue; 1960 } 1961 if (entry->wired_count != 0) { 1962 entry->wired_count++; 1963 entry->eflags |= MAP_ENTRY_USER_WIRED; 1964 entry = entry->next; 1965 continue; 1966 } 1967 1968 /* 1969 * A new wiring requires instantiation of appropriate 1970 * management structures and the faulting in of the 1971 * page. 1972 */ 1973 if (entry->maptype != VM_MAPTYPE_SUBMAP) { 1974 int copyflag = entry->eflags & MAP_ENTRY_NEEDS_COPY; 1975 if (copyflag && ((entry->protection & VM_PROT_WRITE) != 0)) { 1976 vm_map_entry_shadow(entry); 1977 } else if (entry->object.vm_object == NULL && 1978 !map->system_map) { 1979 vm_map_entry_allocate_object(entry); 1980 } 1981 } 1982 entry->wired_count++; 1983 entry->eflags |= MAP_ENTRY_USER_WIRED; 1984 1985 /* 1986 * Now fault in the area. Note that vm_fault_wire() 1987 * may release the map lock temporarily, it will be 1988 * relocked on return. The in-transition 1989 * flag protects the entries. 1990 */ 1991 save_start = entry->start; 1992 save_end = entry->end; 1993 rv = vm_fault_wire(map, entry, TRUE); 1994 if (rv) { 1995 CLIP_CHECK_BACK(entry, save_start); 1996 for (;;) { 1997 KASSERT(entry->wired_count == 1, ("bad wired_count on entry")); 1998 entry->eflags &= ~MAP_ENTRY_USER_WIRED; 1999 entry->wired_count = 0; 2000 if (entry->end == save_end) 2001 break; 2002 entry = entry->next; 2003 KASSERT(entry != &map->header, ("bad entry clip during backout")); 2004 } 2005 end = save_start; /* unwire the rest */ 2006 break; 2007 } 2008 /* 2009 * note that even though the entry might have been 2010 * clipped, the USER_WIRED flag we set prevents 2011 * duplication so we do not have to do a 2012 * clip check. 2013 */ 2014 entry = entry->next; 2015 } 2016 2017 /* 2018 * If we failed fall through to the unwiring section to 2019 * unwire what we had wired so far. 'end' has already 2020 * been adjusted. 2021 */ 2022 if (rv) 2023 new_pageable = 1; 2024 2025 /* 2026 * start_entry might have been clipped if we unlocked the 2027 * map and blocked. No matter how clipped it has gotten 2028 * there should be a fragment that is on our start boundary. 2029 */ 2030 CLIP_CHECK_BACK(start_entry, start); 2031 } 2032 2033 /* 2034 * Deal with the unwiring case. 2035 */ 2036 if (new_pageable) { 2037 /* 2038 * This is the unwiring case. We must first ensure that the 2039 * range to be unwired is really wired down. We know there 2040 * are no holes. 2041 */ 2042 entry = start_entry; 2043 while ((entry != &map->header) && (entry->start < end)) { 2044 if ((entry->eflags & MAP_ENTRY_USER_WIRED) == 0) { 2045 rv = KERN_INVALID_ARGUMENT; 2046 goto done; 2047 } 2048 KASSERT(entry->wired_count != 0, ("wired count was 0 with USER_WIRED set! %p", entry)); 2049 entry = entry->next; 2050 } 2051 2052 /* 2053 * Now decrement the wiring count for each region. If a region 2054 * becomes completely unwired, unwire its physical pages and 2055 * mappings. 2056 */ 2057 /* 2058 * The map entries are processed in a loop, checking to 2059 * make sure the entry is wired and asserting it has a wired 2060 * count. However, another loop was inserted more-or-less in 2061 * the middle of the unwiring path. This loop picks up the 2062 * "entry" loop variable from the first loop without first 2063 * setting it to start_entry. Naturally, the secound loop 2064 * is never entered and the pages backing the entries are 2065 * never unwired. This can lead to a leak of wired pages. 2066 */ 2067 entry = start_entry; 2068 while ((entry != &map->header) && (entry->start < end)) { 2069 KASSERT(entry->eflags & MAP_ENTRY_USER_WIRED, 2070 ("expected USER_WIRED on entry %p", entry)); 2071 entry->eflags &= ~MAP_ENTRY_USER_WIRED; 2072 entry->wired_count--; 2073 if (entry->wired_count == 0) 2074 vm_fault_unwire(map, entry); 2075 entry = entry->next; 2076 } 2077 } 2078 done: 2079 vm_map_unclip_range(map, start_entry, start, real_end, &count, 2080 MAP_CLIP_NO_HOLES); 2081 map->timestamp++; 2082 vm_map_unlock(map); 2083 vm_map_entry_release(count); 2084 return (rv); 2085 } 2086 2087 /* 2088 * vm_map_wire: 2089 * 2090 * Sets the pageability of the specified address 2091 * range in the target map. Regions specified 2092 * as not pageable require locked-down physical 2093 * memory and physical page maps. 2094 * 2095 * The map must not be locked, but a reference 2096 * must remain to the map throughout the call. 2097 * 2098 * This function may be called via the zalloc path and must properly 2099 * reserve map entries for kernel_map. 2100 */ 2101 int 2102 vm_map_wire(vm_map_t map, vm_offset_t start, vm_offset_t real_end, int kmflags) 2103 { 2104 vm_map_entry_t entry; 2105 vm_map_entry_t start_entry; 2106 vm_offset_t end; 2107 int rv = KERN_SUCCESS; 2108 int count; 2109 2110 if (kmflags & KM_KRESERVE) 2111 count = vm_map_entry_kreserve(MAP_RESERVE_COUNT); 2112 else 2113 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 2114 vm_map_lock(map); 2115 VM_MAP_RANGE_CHECK(map, start, real_end); 2116 end = real_end; 2117 2118 start_entry = vm_map_clip_range(map, start, end, &count, MAP_CLIP_NO_HOLES); 2119 if (start_entry == NULL) { 2120 vm_map_unlock(map); 2121 rv = KERN_INVALID_ADDRESS; 2122 goto failure; 2123 } 2124 if ((kmflags & KM_PAGEABLE) == 0) { 2125 /* 2126 * Wiring. 2127 * 2128 * 1. Holding the write lock, we create any shadow or zero-fill 2129 * objects that need to be created. Then we clip each map 2130 * entry to the region to be wired and increment its wiring 2131 * count. We create objects before clipping the map entries 2132 * to avoid object proliferation. 2133 * 2134 * 2. We downgrade to a read lock, and call vm_fault_wire to 2135 * fault in the pages for any newly wired area (wired_count is 2136 * 1). 2137 * 2138 * Downgrading to a read lock for vm_fault_wire avoids a 2139 * possible deadlock with another process that may have faulted 2140 * on one of the pages to be wired (it would mark the page busy, 2141 * blocking us, then in turn block on the map lock that we 2142 * hold). Because of problems in the recursive lock package, 2143 * we cannot upgrade to a write lock in vm_map_lookup. Thus, 2144 * any actions that require the write lock must be done 2145 * beforehand. Because we keep the read lock on the map, the 2146 * copy-on-write status of the entries we modify here cannot 2147 * change. 2148 */ 2149 2150 entry = start_entry; 2151 while ((entry != &map->header) && (entry->start < end)) { 2152 /* 2153 * Trivial case if the entry is already wired 2154 */ 2155 if (entry->wired_count) { 2156 entry->wired_count++; 2157 entry = entry->next; 2158 continue; 2159 } 2160 2161 /* 2162 * The entry is being newly wired, we have to setup 2163 * appropriate management structures. A shadow 2164 * object is required for a copy-on-write region, 2165 * or a normal object for a zero-fill region. We 2166 * do not have to do this for entries that point to sub 2167 * maps because we won't hold the lock on the sub map. 2168 */ 2169 if (entry->maptype != VM_MAPTYPE_SUBMAP) { 2170 int copyflag = entry->eflags & MAP_ENTRY_NEEDS_COPY; 2171 if (copyflag && 2172 ((entry->protection & VM_PROT_WRITE) != 0)) { 2173 vm_map_entry_shadow(entry); 2174 } else if (entry->object.vm_object == NULL && 2175 !map->system_map) { 2176 vm_map_entry_allocate_object(entry); 2177 } 2178 } 2179 2180 entry->wired_count++; 2181 entry = entry->next; 2182 } 2183 2184 /* 2185 * Pass 2. 2186 */ 2187 2188 /* 2189 * HACK HACK HACK HACK 2190 * 2191 * Unlock the map to avoid deadlocks. The in-transit flag 2192 * protects us from most changes but note that 2193 * clipping may still occur. To prevent clipping from 2194 * occuring after the unlock, except for when we are 2195 * blocking in vm_fault_wire, we must run in a critical 2196 * section, otherwise our accesses to entry->start and 2197 * entry->end could be corrupted. We have to enter the 2198 * critical section prior to unlocking so start_entry does 2199 * not change out from under us at the very beginning of the 2200 * loop. 2201 * 2202 * HACK HACK HACK HACK 2203 */ 2204 2205 crit_enter(); 2206 2207 entry = start_entry; 2208 while (entry != &map->header && entry->start < end) { 2209 /* 2210 * If vm_fault_wire fails for any page we need to undo 2211 * what has been done. We decrement the wiring count 2212 * for those pages which have not yet been wired (now) 2213 * and unwire those that have (later). 2214 */ 2215 vm_offset_t save_start = entry->start; 2216 vm_offset_t save_end = entry->end; 2217 2218 if (entry->wired_count == 1) 2219 rv = vm_fault_wire(map, entry, FALSE); 2220 if (rv) { 2221 CLIP_CHECK_BACK(entry, save_start); 2222 for (;;) { 2223 KASSERT(entry->wired_count == 1, ("wired_count changed unexpectedly")); 2224 entry->wired_count = 0; 2225 if (entry->end == save_end) 2226 break; 2227 entry = entry->next; 2228 KASSERT(entry != &map->header, ("bad entry clip during backout")); 2229 } 2230 end = save_start; 2231 break; 2232 } 2233 CLIP_CHECK_FWD(entry, save_end); 2234 entry = entry->next; 2235 } 2236 crit_exit(); 2237 2238 /* 2239 * If a failure occured undo everything by falling through 2240 * to the unwiring code. 'end' has already been adjusted 2241 * appropriately. 2242 */ 2243 if (rv) 2244 kmflags |= KM_PAGEABLE; 2245 2246 /* 2247 * start_entry is still IN_TRANSITION but may have been 2248 * clipped since vm_fault_wire() unlocks and relocks the 2249 * map. No matter how clipped it has gotten there should 2250 * be a fragment that is on our start boundary. 2251 */ 2252 CLIP_CHECK_BACK(start_entry, start); 2253 } 2254 2255 if (kmflags & KM_PAGEABLE) { 2256 /* 2257 * This is the unwiring case. We must first ensure that the 2258 * range to be unwired is really wired down. We know there 2259 * are no holes. 2260 */ 2261 entry = start_entry; 2262 while ((entry != &map->header) && (entry->start < end)) { 2263 if (entry->wired_count == 0) { 2264 rv = KERN_INVALID_ARGUMENT; 2265 goto done; 2266 } 2267 entry = entry->next; 2268 } 2269 2270 /* 2271 * Now decrement the wiring count for each region. If a region 2272 * becomes completely unwired, unwire its physical pages and 2273 * mappings. 2274 */ 2275 entry = start_entry; 2276 while ((entry != &map->header) && (entry->start < end)) { 2277 entry->wired_count--; 2278 if (entry->wired_count == 0) 2279 vm_fault_unwire(map, entry); 2280 entry = entry->next; 2281 } 2282 } 2283 done: 2284 vm_map_unclip_range(map, start_entry, start, real_end, &count, 2285 MAP_CLIP_NO_HOLES); 2286 map->timestamp++; 2287 vm_map_unlock(map); 2288 failure: 2289 if (kmflags & KM_KRESERVE) 2290 vm_map_entry_krelease(count); 2291 else 2292 vm_map_entry_release(count); 2293 return (rv); 2294 } 2295 2296 /* 2297 * vm_map_set_wired_quick() 2298 * 2299 * Mark a newly allocated address range as wired but do not fault in 2300 * the pages. The caller is expected to load the pages into the object. 2301 * 2302 * The map must be locked on entry and will remain locked on return. 2303 */ 2304 void 2305 vm_map_set_wired_quick(vm_map_t map, vm_offset_t addr, vm_size_t size, int *countp) 2306 { 2307 vm_map_entry_t scan; 2308 vm_map_entry_t entry; 2309 2310 entry = vm_map_clip_range(map, addr, addr + size, countp, MAP_CLIP_NO_HOLES); 2311 for (scan = entry; scan != &map->header && scan->start < addr + size; scan = scan->next) { 2312 KKASSERT(entry->wired_count == 0); 2313 entry->wired_count = 1; 2314 } 2315 vm_map_unclip_range(map, entry, addr, addr + size, countp, MAP_CLIP_NO_HOLES); 2316 } 2317 2318 /* 2319 * vm_map_clean 2320 * 2321 * Push any dirty cached pages in the address range to their pager. 2322 * If syncio is TRUE, dirty pages are written synchronously. 2323 * If invalidate is TRUE, any cached pages are freed as well. 2324 * 2325 * Returns an error if any part of the specified range is not mapped. 2326 */ 2327 int 2328 vm_map_clean(vm_map_t map, vm_offset_t start, vm_offset_t end, boolean_t syncio, 2329 boolean_t invalidate) 2330 { 2331 vm_map_entry_t current; 2332 vm_map_entry_t entry; 2333 vm_size_t size; 2334 vm_object_t object; 2335 vm_ooffset_t offset; 2336 2337 vm_map_lock_read(map); 2338 VM_MAP_RANGE_CHECK(map, start, end); 2339 if (!vm_map_lookup_entry(map, start, &entry)) { 2340 vm_map_unlock_read(map); 2341 return (KERN_INVALID_ADDRESS); 2342 } 2343 /* 2344 * Make a first pass to check for holes. 2345 */ 2346 for (current = entry; current->start < end; current = current->next) { 2347 if (current->maptype == VM_MAPTYPE_SUBMAP) { 2348 vm_map_unlock_read(map); 2349 return (KERN_INVALID_ARGUMENT); 2350 } 2351 if (end > current->end && 2352 (current->next == &map->header || 2353 current->end != current->next->start)) { 2354 vm_map_unlock_read(map); 2355 return (KERN_INVALID_ADDRESS); 2356 } 2357 } 2358 2359 if (invalidate) 2360 pmap_remove(vm_map_pmap(map), start, end); 2361 /* 2362 * Make a second pass, cleaning/uncaching pages from the indicated 2363 * objects as we go. 2364 */ 2365 for (current = entry; current->start < end; current = current->next) { 2366 offset = current->offset + (start - current->start); 2367 size = (end <= current->end ? end : current->end) - start; 2368 if (current->maptype == VM_MAPTYPE_SUBMAP) { 2369 vm_map_t smap; 2370 vm_map_entry_t tentry; 2371 vm_size_t tsize; 2372 2373 smap = current->object.sub_map; 2374 vm_map_lock_read(smap); 2375 vm_map_lookup_entry(smap, offset, &tentry); 2376 tsize = tentry->end - offset; 2377 if (tsize < size) 2378 size = tsize; 2379 object = tentry->object.vm_object; 2380 offset = tentry->offset + (offset - tentry->start); 2381 vm_map_unlock_read(smap); 2382 } else { 2383 object = current->object.vm_object; 2384 } 2385 /* 2386 * Note that there is absolutely no sense in writing out 2387 * anonymous objects, so we track down the vnode object 2388 * to write out. 2389 * We invalidate (remove) all pages from the address space 2390 * anyway, for semantic correctness. 2391 * 2392 * note: certain anonymous maps, such as MAP_NOSYNC maps, 2393 * may start out with a NULL object. 2394 */ 2395 while (object && object->backing_object) { 2396 offset += object->backing_object_offset; 2397 object = object->backing_object; 2398 if (object->size < OFF_TO_IDX( offset + size)) 2399 size = IDX_TO_OFF(object->size) - offset; 2400 } 2401 if (object && (object->type == OBJT_VNODE) && 2402 (current->protection & VM_PROT_WRITE)) { 2403 /* 2404 * Flush pages if writing is allowed, invalidate them 2405 * if invalidation requested. Pages undergoing I/O 2406 * will be ignored by vm_object_page_remove(). 2407 * 2408 * We cannot lock the vnode and then wait for paging 2409 * to complete without deadlocking against vm_fault. 2410 * Instead we simply call vm_object_page_remove() and 2411 * allow it to block internally on a page-by-page 2412 * basis when it encounters pages undergoing async 2413 * I/O. 2414 */ 2415 int flags; 2416 2417 vm_object_reference(object); 2418 vn_lock(object->handle, LK_EXCLUSIVE | LK_RETRY); 2419 flags = (syncio || invalidate) ? OBJPC_SYNC : 0; 2420 flags |= invalidate ? OBJPC_INVAL : 0; 2421 2422 /* 2423 * When operating on a virtual page table just 2424 * flush the whole object. XXX we probably ought 2425 * to 2426 */ 2427 switch(current->maptype) { 2428 case VM_MAPTYPE_NORMAL: 2429 vm_object_page_clean(object, 2430 OFF_TO_IDX(offset), 2431 OFF_TO_IDX(offset + size + PAGE_MASK), 2432 flags); 2433 break; 2434 case VM_MAPTYPE_VPAGETABLE: 2435 vm_object_page_clean(object, 0, 0, flags); 2436 break; 2437 } 2438 vn_unlock(((struct vnode *)object->handle)); 2439 vm_object_deallocate(object); 2440 } 2441 if (object && invalidate && 2442 ((object->type == OBJT_VNODE) || 2443 (object->type == OBJT_DEVICE))) { 2444 int clean_only = 2445 (object->type == OBJT_DEVICE) ? FALSE : TRUE; 2446 vm_object_reference(object); 2447 switch(current->maptype) { 2448 case VM_MAPTYPE_NORMAL: 2449 vm_object_page_remove(object, 2450 OFF_TO_IDX(offset), 2451 OFF_TO_IDX(offset + size + PAGE_MASK), 2452 clean_only); 2453 break; 2454 case VM_MAPTYPE_VPAGETABLE: 2455 vm_object_page_remove(object, 0, 0, clean_only); 2456 break; 2457 } 2458 vm_object_deallocate(object); 2459 } 2460 start += size; 2461 } 2462 2463 vm_map_unlock_read(map); 2464 return (KERN_SUCCESS); 2465 } 2466 2467 /* 2468 * vm_map_entry_unwire: [ internal use only ] 2469 * 2470 * Make the region specified by this entry pageable. 2471 * 2472 * The map in question should be locked. 2473 * [This is the reason for this routine's existence.] 2474 */ 2475 static void 2476 vm_map_entry_unwire(vm_map_t map, vm_map_entry_t entry) 2477 { 2478 entry->eflags &= ~MAP_ENTRY_USER_WIRED; 2479 entry->wired_count = 0; 2480 vm_fault_unwire(map, entry); 2481 } 2482 2483 /* 2484 * vm_map_entry_delete: [ internal use only ] 2485 * 2486 * Deallocate the given entry from the target map. 2487 */ 2488 static void 2489 vm_map_entry_delete(vm_map_t map, vm_map_entry_t entry, int *countp) 2490 { 2491 vm_map_entry_unlink(map, entry); 2492 map->size -= entry->end - entry->start; 2493 2494 switch(entry->maptype) { 2495 case VM_MAPTYPE_NORMAL: 2496 case VM_MAPTYPE_VPAGETABLE: 2497 vm_object_deallocate(entry->object.vm_object); 2498 break; 2499 default: 2500 break; 2501 } 2502 2503 vm_map_entry_dispose(map, entry, countp); 2504 } 2505 2506 /* 2507 * vm_map_delete: [ internal use only ] 2508 * 2509 * Deallocates the given address range from the target 2510 * map. 2511 */ 2512 int 2513 vm_map_delete(vm_map_t map, vm_offset_t start, vm_offset_t end, int *countp) 2514 { 2515 vm_object_t object; 2516 vm_map_entry_t entry; 2517 vm_map_entry_t first_entry; 2518 2519 again: 2520 /* 2521 * Find the start of the region, and clip it. Set entry to point 2522 * at the first record containing the requested address or, if no 2523 * such record exists, the next record with a greater address. The 2524 * loop will run from this point until a record beyond the termination 2525 * address is encountered. 2526 * 2527 * map->hint must be adjusted to not point to anything we delete, 2528 * so set it to the entry prior to the one being deleted. 2529 * 2530 * GGG see other GGG comment. 2531 */ 2532 if (vm_map_lookup_entry(map, start, &first_entry)) { 2533 entry = first_entry; 2534 vm_map_clip_start(map, entry, start, countp); 2535 map->hint = entry->prev; /* possible problem XXX */ 2536 } else { 2537 map->hint = first_entry; /* possible problem XXX */ 2538 entry = first_entry->next; 2539 } 2540 2541 /* 2542 * If a hole opens up prior to the current first_free then 2543 * adjust first_free. As with map->hint, map->first_free 2544 * cannot be left set to anything we might delete. 2545 */ 2546 if (entry == &map->header) { 2547 map->first_free = &map->header; 2548 } else if (map->first_free->start >= start) { 2549 map->first_free = entry->prev; 2550 } 2551 2552 /* 2553 * Step through all entries in this region 2554 */ 2555 2556 while ((entry != &map->header) && (entry->start < end)) { 2557 vm_map_entry_t next; 2558 vm_offset_t s, e; 2559 vm_pindex_t offidxstart, offidxend, count; 2560 2561 /* 2562 * If we hit an in-transition entry we have to sleep and 2563 * retry. It's easier (and not really slower) to just retry 2564 * since this case occurs so rarely and the hint is already 2565 * pointing at the right place. We have to reset the 2566 * start offset so as not to accidently delete an entry 2567 * another process just created in vacated space. 2568 */ 2569 if (entry->eflags & MAP_ENTRY_IN_TRANSITION) { 2570 entry->eflags |= MAP_ENTRY_NEEDS_WAKEUP; 2571 start = entry->start; 2572 ++mycpu->gd_cnt.v_intrans_coll; 2573 ++mycpu->gd_cnt.v_intrans_wait; 2574 vm_map_transition_wait(map); 2575 goto again; 2576 } 2577 vm_map_clip_end(map, entry, end, countp); 2578 2579 s = entry->start; 2580 e = entry->end; 2581 next = entry->next; 2582 2583 offidxstart = OFF_TO_IDX(entry->offset); 2584 count = OFF_TO_IDX(e - s); 2585 object = entry->object.vm_object; 2586 2587 /* 2588 * Unwire before removing addresses from the pmap; otherwise, 2589 * unwiring will put the entries back in the pmap. 2590 */ 2591 if (entry->wired_count != 0) 2592 vm_map_entry_unwire(map, entry); 2593 2594 offidxend = offidxstart + count; 2595 2596 if (object == &kernel_object) { 2597 vm_object_page_remove(object, offidxstart, offidxend, FALSE); 2598 } else { 2599 pmap_remove(map->pmap, s, e); 2600 if (object != NULL && 2601 object->ref_count != 1 && 2602 (object->flags & (OBJ_NOSPLIT|OBJ_ONEMAPPING)) == OBJ_ONEMAPPING && 2603 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) { 2604 vm_object_collapse(object); 2605 vm_object_page_remove(object, offidxstart, offidxend, FALSE); 2606 if (object->type == OBJT_SWAP) { 2607 swap_pager_freespace(object, offidxstart, count); 2608 } 2609 if (offidxend >= object->size && 2610 offidxstart < object->size) { 2611 object->size = offidxstart; 2612 } 2613 } 2614 } 2615 2616 /* 2617 * Delete the entry (which may delete the object) only after 2618 * removing all pmap entries pointing to its pages. 2619 * (Otherwise, its page frames may be reallocated, and any 2620 * modify bits will be set in the wrong object!) 2621 */ 2622 vm_map_entry_delete(map, entry, countp); 2623 entry = next; 2624 } 2625 return (KERN_SUCCESS); 2626 } 2627 2628 /* 2629 * vm_map_remove: 2630 * 2631 * Remove the given address range from the target map. 2632 * This is the exported form of vm_map_delete. 2633 */ 2634 int 2635 vm_map_remove(vm_map_t map, vm_offset_t start, vm_offset_t end) 2636 { 2637 int result; 2638 int count; 2639 2640 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 2641 vm_map_lock(map); 2642 VM_MAP_RANGE_CHECK(map, start, end); 2643 result = vm_map_delete(map, start, end, &count); 2644 vm_map_unlock(map); 2645 vm_map_entry_release(count); 2646 2647 return (result); 2648 } 2649 2650 /* 2651 * vm_map_check_protection: 2652 * 2653 * Assert that the target map allows the specified 2654 * privilege on the entire address region given. 2655 * The entire region must be allocated. 2656 */ 2657 boolean_t 2658 vm_map_check_protection(vm_map_t map, vm_offset_t start, vm_offset_t end, 2659 vm_prot_t protection) 2660 { 2661 vm_map_entry_t entry; 2662 vm_map_entry_t tmp_entry; 2663 2664 if (!vm_map_lookup_entry(map, start, &tmp_entry)) { 2665 return (FALSE); 2666 } 2667 entry = tmp_entry; 2668 2669 while (start < end) { 2670 if (entry == &map->header) { 2671 return (FALSE); 2672 } 2673 /* 2674 * No holes allowed! 2675 */ 2676 2677 if (start < entry->start) { 2678 return (FALSE); 2679 } 2680 /* 2681 * Check protection associated with entry. 2682 */ 2683 2684 if ((entry->protection & protection) != protection) { 2685 return (FALSE); 2686 } 2687 /* go to next entry */ 2688 2689 start = entry->end; 2690 entry = entry->next; 2691 } 2692 return (TRUE); 2693 } 2694 2695 /* 2696 * Split the pages in a map entry into a new object. This affords 2697 * easier removal of unused pages, and keeps object inheritance from 2698 * being a negative impact on memory usage. 2699 */ 2700 static void 2701 vm_map_split(vm_map_entry_t entry) 2702 { 2703 vm_page_t m; 2704 vm_object_t orig_object, new_object, source; 2705 vm_offset_t s, e; 2706 vm_pindex_t offidxstart, offidxend, idx; 2707 vm_size_t size; 2708 vm_ooffset_t offset; 2709 2710 orig_object = entry->object.vm_object; 2711 if (orig_object->type != OBJT_DEFAULT && orig_object->type != OBJT_SWAP) 2712 return; 2713 if (orig_object->ref_count <= 1) 2714 return; 2715 2716 offset = entry->offset; 2717 s = entry->start; 2718 e = entry->end; 2719 2720 offidxstart = OFF_TO_IDX(offset); 2721 offidxend = offidxstart + OFF_TO_IDX(e - s); 2722 size = offidxend - offidxstart; 2723 2724 new_object = vm_pager_allocate(orig_object->type, NULL, 2725 IDX_TO_OFF(size), VM_PROT_ALL, 0); 2726 if (new_object == NULL) 2727 return; 2728 2729 source = orig_object->backing_object; 2730 if (source != NULL) { 2731 vm_object_reference(source); /* Referenced by new_object */ 2732 LIST_INSERT_HEAD(&source->shadow_head, 2733 new_object, shadow_list); 2734 vm_object_clear_flag(source, OBJ_ONEMAPPING); 2735 new_object->backing_object_offset = 2736 orig_object->backing_object_offset + IDX_TO_OFF(offidxstart); 2737 new_object->backing_object = source; 2738 source->shadow_count++; 2739 source->generation++; 2740 } 2741 2742 for (idx = 0; idx < size; idx++) { 2743 vm_page_t m; 2744 2745 /* 2746 * A critical section is required to avoid a race between 2747 * the lookup and an interrupt/unbusy/free and our busy 2748 * check. 2749 */ 2750 crit_enter(); 2751 retry: 2752 m = vm_page_lookup(orig_object, offidxstart + idx); 2753 if (m == NULL) { 2754 crit_exit(); 2755 continue; 2756 } 2757 2758 /* 2759 * We must wait for pending I/O to complete before we can 2760 * rename the page. 2761 * 2762 * We do not have to VM_PROT_NONE the page as mappings should 2763 * not be changed by this operation. 2764 */ 2765 if (vm_page_sleep_busy(m, TRUE, "spltwt")) 2766 goto retry; 2767 vm_page_busy(m); 2768 vm_page_rename(m, new_object, idx); 2769 /* page automatically made dirty by rename and cache handled */ 2770 vm_page_busy(m); 2771 crit_exit(); 2772 } 2773 2774 if (orig_object->type == OBJT_SWAP) { 2775 vm_object_pip_add(orig_object, 1); 2776 /* 2777 * copy orig_object pages into new_object 2778 * and destroy unneeded pages in 2779 * shadow object. 2780 */ 2781 swap_pager_copy(orig_object, new_object, offidxstart, 0); 2782 vm_object_pip_wakeup(orig_object); 2783 } 2784 2785 /* 2786 * Wakeup the pages we played with. No spl protection is needed 2787 * for a simple wakeup. 2788 */ 2789 for (idx = 0; idx < size; idx++) { 2790 m = vm_page_lookup(new_object, idx); 2791 if (m) 2792 vm_page_wakeup(m); 2793 } 2794 2795 entry->object.vm_object = new_object; 2796 entry->offset = 0LL; 2797 vm_object_deallocate(orig_object); 2798 } 2799 2800 /* 2801 * vm_map_copy_entry: 2802 * 2803 * Copies the contents of the source entry to the destination 2804 * entry. The entries *must* be aligned properly. 2805 */ 2806 static void 2807 vm_map_copy_entry(vm_map_t src_map, vm_map_t dst_map, 2808 vm_map_entry_t src_entry, vm_map_entry_t dst_entry) 2809 { 2810 vm_object_t src_object; 2811 2812 if (dst_entry->maptype == VM_MAPTYPE_SUBMAP) 2813 return; 2814 if (src_entry->maptype == VM_MAPTYPE_SUBMAP) 2815 return; 2816 2817 if (src_entry->wired_count == 0) { 2818 /* 2819 * If the source entry is marked needs_copy, it is already 2820 * write-protected. 2821 */ 2822 if ((src_entry->eflags & MAP_ENTRY_NEEDS_COPY) == 0) { 2823 pmap_protect(src_map->pmap, 2824 src_entry->start, 2825 src_entry->end, 2826 src_entry->protection & ~VM_PROT_WRITE); 2827 } 2828 2829 /* 2830 * Make a copy of the object. 2831 */ 2832 if ((src_object = src_entry->object.vm_object) != NULL) { 2833 if ((src_object->handle == NULL) && 2834 (src_object->type == OBJT_DEFAULT || 2835 src_object->type == OBJT_SWAP)) { 2836 vm_object_collapse(src_object); 2837 if ((src_object->flags & (OBJ_NOSPLIT|OBJ_ONEMAPPING)) == OBJ_ONEMAPPING) { 2838 vm_map_split(src_entry); 2839 src_object = src_entry->object.vm_object; 2840 } 2841 } 2842 2843 vm_object_reference(src_object); 2844 vm_object_clear_flag(src_object, OBJ_ONEMAPPING); 2845 dst_entry->object.vm_object = src_object; 2846 src_entry->eflags |= (MAP_ENTRY_COW|MAP_ENTRY_NEEDS_COPY); 2847 dst_entry->eflags |= (MAP_ENTRY_COW|MAP_ENTRY_NEEDS_COPY); 2848 dst_entry->offset = src_entry->offset; 2849 } else { 2850 dst_entry->object.vm_object = NULL; 2851 dst_entry->offset = 0; 2852 } 2853 2854 pmap_copy(dst_map->pmap, src_map->pmap, dst_entry->start, 2855 dst_entry->end - dst_entry->start, src_entry->start); 2856 } else { 2857 /* 2858 * Of course, wired down pages can't be set copy-on-write. 2859 * Cause wired pages to be copied into the new map by 2860 * simulating faults (the new pages are pageable) 2861 */ 2862 vm_fault_copy_entry(dst_map, src_map, dst_entry, src_entry); 2863 } 2864 } 2865 2866 /* 2867 * vmspace_fork: 2868 * Create a new process vmspace structure and vm_map 2869 * based on those of an existing process. The new map 2870 * is based on the old map, according to the inheritance 2871 * values on the regions in that map. 2872 * 2873 * The source map must not be locked. 2874 */ 2875 struct vmspace * 2876 vmspace_fork(struct vmspace *vm1) 2877 { 2878 struct vmspace *vm2; 2879 vm_map_t old_map = &vm1->vm_map; 2880 vm_map_t new_map; 2881 vm_map_entry_t old_entry; 2882 vm_map_entry_t new_entry; 2883 vm_object_t object; 2884 int count; 2885 2886 vm_map_lock(old_map); 2887 old_map->infork = 1; 2888 2889 /* 2890 * XXX Note: upcalls are not copied. 2891 */ 2892 vm2 = vmspace_alloc(old_map->min_offset, old_map->max_offset); 2893 bcopy(&vm1->vm_startcopy, &vm2->vm_startcopy, 2894 (caddr_t)&vm1->vm_endcopy - (caddr_t)&vm1->vm_startcopy); 2895 new_map = &vm2->vm_map; /* XXX */ 2896 new_map->timestamp = 1; 2897 2898 count = 0; 2899 old_entry = old_map->header.next; 2900 while (old_entry != &old_map->header) { 2901 ++count; 2902 old_entry = old_entry->next; 2903 } 2904 2905 count = vm_map_entry_reserve(count + MAP_RESERVE_COUNT); 2906 2907 old_entry = old_map->header.next; 2908 while (old_entry != &old_map->header) { 2909 if (old_entry->maptype == VM_MAPTYPE_SUBMAP) 2910 panic("vm_map_fork: encountered a submap"); 2911 2912 switch (old_entry->inheritance) { 2913 case VM_INHERIT_NONE: 2914 break; 2915 2916 case VM_INHERIT_SHARE: 2917 /* 2918 * Clone the entry, creating the shared object if 2919 * necessary. 2920 */ 2921 object = old_entry->object.vm_object; 2922 if (object == NULL) { 2923 vm_map_entry_allocate_object(old_entry); 2924 object = old_entry->object.vm_object; 2925 } 2926 2927 /* 2928 * Add the reference before calling vm_map_entry_shadow 2929 * to insure that a shadow object is created. 2930 */ 2931 vm_object_reference(object); 2932 if (old_entry->eflags & MAP_ENTRY_NEEDS_COPY) { 2933 vm_map_entry_shadow(old_entry); 2934 /* Transfer the second reference too. */ 2935 vm_object_reference( 2936 old_entry->object.vm_object); 2937 vm_object_deallocate(object); 2938 object = old_entry->object.vm_object; 2939 } 2940 vm_object_clear_flag(object, OBJ_ONEMAPPING); 2941 2942 /* 2943 * Clone the entry, referencing the shared object. 2944 */ 2945 new_entry = vm_map_entry_create(new_map, &count); 2946 *new_entry = *old_entry; 2947 new_entry->eflags &= ~MAP_ENTRY_USER_WIRED; 2948 new_entry->wired_count = 0; 2949 2950 /* 2951 * Insert the entry into the new map -- we know we're 2952 * inserting at the end of the new map. 2953 */ 2954 2955 vm_map_entry_link(new_map, new_map->header.prev, 2956 new_entry); 2957 2958 /* 2959 * Update the physical map 2960 */ 2961 2962 pmap_copy(new_map->pmap, old_map->pmap, 2963 new_entry->start, 2964 (old_entry->end - old_entry->start), 2965 old_entry->start); 2966 break; 2967 2968 case VM_INHERIT_COPY: 2969 /* 2970 * Clone the entry and link into the map. 2971 */ 2972 new_entry = vm_map_entry_create(new_map, &count); 2973 *new_entry = *old_entry; 2974 new_entry->eflags &= ~MAP_ENTRY_USER_WIRED; 2975 new_entry->wired_count = 0; 2976 new_entry->object.vm_object = NULL; 2977 vm_map_entry_link(new_map, new_map->header.prev, 2978 new_entry); 2979 vm_map_copy_entry(old_map, new_map, old_entry, 2980 new_entry); 2981 break; 2982 } 2983 old_entry = old_entry->next; 2984 } 2985 2986 new_map->size = old_map->size; 2987 old_map->infork = 0; 2988 vm_map_unlock(old_map); 2989 vm_map_entry_release(count); 2990 2991 return (vm2); 2992 } 2993 2994 int 2995 vm_map_stack (vm_map_t map, vm_offset_t addrbos, vm_size_t max_ssize, 2996 vm_prot_t prot, vm_prot_t max, int cow) 2997 { 2998 vm_map_entry_t prev_entry; 2999 vm_map_entry_t new_stack_entry; 3000 vm_size_t init_ssize; 3001 int rv; 3002 int count; 3003 3004 if (VM_MIN_USER_ADDRESS > 0 && addrbos < VM_MIN_USER_ADDRESS) 3005 return (KERN_NO_SPACE); 3006 3007 if (max_ssize < sgrowsiz) 3008 init_ssize = max_ssize; 3009 else 3010 init_ssize = sgrowsiz; 3011 3012 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 3013 vm_map_lock(map); 3014 3015 /* If addr is already mapped, no go */ 3016 if (vm_map_lookup_entry(map, addrbos, &prev_entry)) { 3017 vm_map_unlock(map); 3018 vm_map_entry_release(count); 3019 return (KERN_NO_SPACE); 3020 } 3021 3022 /* If we would blow our VMEM resource limit, no go */ 3023 if (map->size + init_ssize > 3024 curproc->p_rlimit[RLIMIT_VMEM].rlim_cur) { 3025 vm_map_unlock(map); 3026 vm_map_entry_release(count); 3027 return (KERN_NO_SPACE); 3028 } 3029 3030 /* If we can't accomodate max_ssize in the current mapping, 3031 * no go. However, we need to be aware that subsequent user 3032 * mappings might map into the space we have reserved for 3033 * stack, and currently this space is not protected. 3034 * 3035 * Hopefully we will at least detect this condition 3036 * when we try to grow the stack. 3037 */ 3038 if ((prev_entry->next != &map->header) && 3039 (prev_entry->next->start < addrbos + max_ssize)) { 3040 vm_map_unlock(map); 3041 vm_map_entry_release(count); 3042 return (KERN_NO_SPACE); 3043 } 3044 3045 /* We initially map a stack of only init_ssize. We will 3046 * grow as needed later. Since this is to be a grow 3047 * down stack, we map at the top of the range. 3048 * 3049 * Note: we would normally expect prot and max to be 3050 * VM_PROT_ALL, and cow to be 0. Possibly we should 3051 * eliminate these as input parameters, and just 3052 * pass these values here in the insert call. 3053 */ 3054 rv = vm_map_insert(map, &count, 3055 NULL, 0, addrbos + max_ssize - init_ssize, 3056 addrbos + max_ssize, 3057 VM_MAPTYPE_NORMAL, 3058 prot, max, 3059 cow); 3060 3061 /* Now set the avail_ssize amount */ 3062 if (rv == KERN_SUCCESS) { 3063 if (prev_entry != &map->header) 3064 vm_map_clip_end(map, prev_entry, addrbos + max_ssize - init_ssize, &count); 3065 new_stack_entry = prev_entry->next; 3066 if (new_stack_entry->end != addrbos + max_ssize || 3067 new_stack_entry->start != addrbos + max_ssize - init_ssize) 3068 panic ("Bad entry start/end for new stack entry"); 3069 else 3070 new_stack_entry->aux.avail_ssize = max_ssize - init_ssize; 3071 } 3072 3073 vm_map_unlock(map); 3074 vm_map_entry_release(count); 3075 return (rv); 3076 } 3077 3078 /* Attempts to grow a vm stack entry. Returns KERN_SUCCESS if the 3079 * desired address is already mapped, or if we successfully grow 3080 * the stack. Also returns KERN_SUCCESS if addr is outside the 3081 * stack range (this is strange, but preserves compatibility with 3082 * the grow function in vm_machdep.c). 3083 */ 3084 int 3085 vm_map_growstack (struct proc *p, vm_offset_t addr) 3086 { 3087 vm_map_entry_t prev_entry; 3088 vm_map_entry_t stack_entry; 3089 vm_map_entry_t new_stack_entry; 3090 struct vmspace *vm = p->p_vmspace; 3091 vm_map_t map = &vm->vm_map; 3092 vm_offset_t end; 3093 int grow_amount; 3094 int rv = KERN_SUCCESS; 3095 int is_procstack; 3096 int use_read_lock = 1; 3097 int count; 3098 3099 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 3100 Retry: 3101 if (use_read_lock) 3102 vm_map_lock_read(map); 3103 else 3104 vm_map_lock(map); 3105 3106 /* If addr is already in the entry range, no need to grow.*/ 3107 if (vm_map_lookup_entry(map, addr, &prev_entry)) 3108 goto done; 3109 3110 if ((stack_entry = prev_entry->next) == &map->header) 3111 goto done; 3112 if (prev_entry == &map->header) 3113 end = stack_entry->start - stack_entry->aux.avail_ssize; 3114 else 3115 end = prev_entry->end; 3116 3117 /* This next test mimics the old grow function in vm_machdep.c. 3118 * It really doesn't quite make sense, but we do it anyway 3119 * for compatibility. 3120 * 3121 * If not growable stack, return success. This signals the 3122 * caller to proceed as he would normally with normal vm. 3123 */ 3124 if (stack_entry->aux.avail_ssize < 1 || 3125 addr >= stack_entry->start || 3126 addr < stack_entry->start - stack_entry->aux.avail_ssize) { 3127 goto done; 3128 } 3129 3130 /* Find the minimum grow amount */ 3131 grow_amount = roundup (stack_entry->start - addr, PAGE_SIZE); 3132 if (grow_amount > stack_entry->aux.avail_ssize) { 3133 rv = KERN_NO_SPACE; 3134 goto done; 3135 } 3136 3137 /* If there is no longer enough space between the entries 3138 * nogo, and adjust the available space. Note: this 3139 * should only happen if the user has mapped into the 3140 * stack area after the stack was created, and is 3141 * probably an error. 3142 * 3143 * This also effectively destroys any guard page the user 3144 * might have intended by limiting the stack size. 3145 */ 3146 if (grow_amount > stack_entry->start - end) { 3147 if (use_read_lock && vm_map_lock_upgrade(map)) { 3148 use_read_lock = 0; 3149 goto Retry; 3150 } 3151 use_read_lock = 0; 3152 stack_entry->aux.avail_ssize = stack_entry->start - end; 3153 rv = KERN_NO_SPACE; 3154 goto done; 3155 } 3156 3157 is_procstack = addr >= (vm_offset_t)vm->vm_maxsaddr; 3158 3159 /* If this is the main process stack, see if we're over the 3160 * stack limit. 3161 */ 3162 if (is_procstack && (ctob(vm->vm_ssize) + grow_amount > 3163 p->p_rlimit[RLIMIT_STACK].rlim_cur)) { 3164 rv = KERN_NO_SPACE; 3165 goto done; 3166 } 3167 3168 /* Round up the grow amount modulo SGROWSIZ */ 3169 grow_amount = roundup (grow_amount, sgrowsiz); 3170 if (grow_amount > stack_entry->aux.avail_ssize) { 3171 grow_amount = stack_entry->aux.avail_ssize; 3172 } 3173 if (is_procstack && (ctob(vm->vm_ssize) + grow_amount > 3174 p->p_rlimit[RLIMIT_STACK].rlim_cur)) { 3175 grow_amount = p->p_rlimit[RLIMIT_STACK].rlim_cur - 3176 ctob(vm->vm_ssize); 3177 } 3178 3179 /* If we would blow our VMEM resource limit, no go */ 3180 if (map->size + grow_amount > p->p_rlimit[RLIMIT_VMEM].rlim_cur) { 3181 rv = KERN_NO_SPACE; 3182 goto done; 3183 } 3184 3185 if (use_read_lock && vm_map_lock_upgrade(map)) { 3186 use_read_lock = 0; 3187 goto Retry; 3188 } 3189 use_read_lock = 0; 3190 3191 /* Get the preliminary new entry start value */ 3192 addr = stack_entry->start - grow_amount; 3193 3194 /* If this puts us into the previous entry, cut back our growth 3195 * to the available space. Also, see the note above. 3196 */ 3197 if (addr < end) { 3198 stack_entry->aux.avail_ssize = stack_entry->start - end; 3199 addr = end; 3200 } 3201 3202 rv = vm_map_insert(map, &count, 3203 NULL, 0, addr, stack_entry->start, 3204 VM_MAPTYPE_NORMAL, 3205 VM_PROT_ALL, VM_PROT_ALL, 3206 0); 3207 3208 /* Adjust the available stack space by the amount we grew. */ 3209 if (rv == KERN_SUCCESS) { 3210 if (prev_entry != &map->header) 3211 vm_map_clip_end(map, prev_entry, addr, &count); 3212 new_stack_entry = prev_entry->next; 3213 if (new_stack_entry->end != stack_entry->start || 3214 new_stack_entry->start != addr) 3215 panic ("Bad stack grow start/end in new stack entry"); 3216 else { 3217 new_stack_entry->aux.avail_ssize = 3218 stack_entry->aux.avail_ssize - 3219 (new_stack_entry->end - new_stack_entry->start); 3220 if (is_procstack) 3221 vm->vm_ssize += btoc(new_stack_entry->end - 3222 new_stack_entry->start); 3223 } 3224 } 3225 3226 done: 3227 if (use_read_lock) 3228 vm_map_unlock_read(map); 3229 else 3230 vm_map_unlock(map); 3231 vm_map_entry_release(count); 3232 return (rv); 3233 } 3234 3235 /* 3236 * Unshare the specified VM space for exec. If other processes are 3237 * mapped to it, then create a new one. The new vmspace is null. 3238 */ 3239 void 3240 vmspace_exec(struct proc *p, struct vmspace *vmcopy) 3241 { 3242 struct vmspace *oldvmspace = p->p_vmspace; 3243 struct vmspace *newvmspace; 3244 vm_map_t map = &p->p_vmspace->vm_map; 3245 3246 /* 3247 * If we are execing a resident vmspace we fork it, otherwise 3248 * we create a new vmspace. Note that exitingcnt and upcalls 3249 * are not copied to the new vmspace. 3250 */ 3251 if (vmcopy) { 3252 newvmspace = vmspace_fork(vmcopy); 3253 } else { 3254 newvmspace = vmspace_alloc(map->min_offset, map->max_offset); 3255 bcopy(&oldvmspace->vm_startcopy, &newvmspace->vm_startcopy, 3256 (caddr_t)&oldvmspace->vm_endcopy - 3257 (caddr_t)&oldvmspace->vm_startcopy); 3258 } 3259 3260 /* 3261 * Finish initializing the vmspace before assigning it 3262 * to the process. The vmspace will become the current vmspace 3263 * if p == curproc. 3264 */ 3265 pmap_pinit2(vmspace_pmap(newvmspace)); 3266 pmap_replacevm(p, newvmspace, 0); 3267 sysref_put(&oldvmspace->vm_sysref); 3268 } 3269 3270 /* 3271 * Unshare the specified VM space for forcing COW. This 3272 * is called by rfork, for the (RFMEM|RFPROC) == 0 case. 3273 * 3274 * The exitingcnt test is not strictly necessary but has been 3275 * included for code sanity (to make the code a bit more deterministic). 3276 */ 3277 3278 void 3279 vmspace_unshare(struct proc *p) 3280 { 3281 struct vmspace *oldvmspace = p->p_vmspace; 3282 struct vmspace *newvmspace; 3283 3284 if (oldvmspace->vm_sysref.refcnt == 1 && oldvmspace->vm_exitingcnt == 0) 3285 return; 3286 newvmspace = vmspace_fork(oldvmspace); 3287 pmap_pinit2(vmspace_pmap(newvmspace)); 3288 pmap_replacevm(p, newvmspace, 0); 3289 sysref_put(&oldvmspace->vm_sysref); 3290 } 3291 3292 /* 3293 * vm_map_lookup: 3294 * 3295 * Finds the VM object, offset, and 3296 * protection for a given virtual address in the 3297 * specified map, assuming a page fault of the 3298 * type specified. 3299 * 3300 * Leaves the map in question locked for read; return 3301 * values are guaranteed until a vm_map_lookup_done 3302 * call is performed. Note that the map argument 3303 * is in/out; the returned map must be used in 3304 * the call to vm_map_lookup_done. 3305 * 3306 * A handle (out_entry) is returned for use in 3307 * vm_map_lookup_done, to make that fast. 3308 * 3309 * If a lookup is requested with "write protection" 3310 * specified, the map may be changed to perform virtual 3311 * copying operations, although the data referenced will 3312 * remain the same. 3313 */ 3314 int 3315 vm_map_lookup(vm_map_t *var_map, /* IN/OUT */ 3316 vm_offset_t vaddr, 3317 vm_prot_t fault_typea, 3318 vm_map_entry_t *out_entry, /* OUT */ 3319 vm_object_t *object, /* OUT */ 3320 vm_pindex_t *pindex, /* OUT */ 3321 vm_prot_t *out_prot, /* OUT */ 3322 boolean_t *wired) /* OUT */ 3323 { 3324 vm_map_entry_t entry; 3325 vm_map_t map = *var_map; 3326 vm_prot_t prot; 3327 vm_prot_t fault_type = fault_typea; 3328 int use_read_lock = 1; 3329 int rv = KERN_SUCCESS; 3330 3331 RetryLookup: 3332 if (use_read_lock) 3333 vm_map_lock_read(map); 3334 else 3335 vm_map_lock(map); 3336 3337 /* 3338 * If the map has an interesting hint, try it before calling full 3339 * blown lookup routine. 3340 */ 3341 entry = map->hint; 3342 *out_entry = entry; 3343 3344 if ((entry == &map->header) || 3345 (vaddr < entry->start) || (vaddr >= entry->end)) { 3346 vm_map_entry_t tmp_entry; 3347 3348 /* 3349 * Entry was either not a valid hint, or the vaddr was not 3350 * contained in the entry, so do a full lookup. 3351 */ 3352 if (!vm_map_lookup_entry(map, vaddr, &tmp_entry)) { 3353 rv = KERN_INVALID_ADDRESS; 3354 goto done; 3355 } 3356 3357 entry = tmp_entry; 3358 *out_entry = entry; 3359 } 3360 3361 /* 3362 * Handle submaps. 3363 */ 3364 if (entry->maptype == VM_MAPTYPE_SUBMAP) { 3365 vm_map_t old_map = map; 3366 3367 *var_map = map = entry->object.sub_map; 3368 if (use_read_lock) 3369 vm_map_unlock_read(old_map); 3370 else 3371 vm_map_unlock(old_map); 3372 use_read_lock = 1; 3373 goto RetryLookup; 3374 } 3375 3376 /* 3377 * Check whether this task is allowed to have this page. 3378 * Note the special case for MAP_ENTRY_COW 3379 * pages with an override. This is to implement a forced 3380 * COW for debuggers. 3381 */ 3382 3383 if (fault_type & VM_PROT_OVERRIDE_WRITE) 3384 prot = entry->max_protection; 3385 else 3386 prot = entry->protection; 3387 3388 fault_type &= (VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 3389 if ((fault_type & prot) != fault_type) { 3390 rv = KERN_PROTECTION_FAILURE; 3391 goto done; 3392 } 3393 3394 if ((entry->eflags & MAP_ENTRY_USER_WIRED) && 3395 (entry->eflags & MAP_ENTRY_COW) && 3396 (fault_type & VM_PROT_WRITE) && 3397 (fault_typea & VM_PROT_OVERRIDE_WRITE) == 0) { 3398 rv = KERN_PROTECTION_FAILURE; 3399 goto done; 3400 } 3401 3402 /* 3403 * If this page is not pageable, we have to get it for all possible 3404 * accesses. 3405 */ 3406 *wired = (entry->wired_count != 0); 3407 if (*wired) 3408 prot = fault_type = entry->protection; 3409 3410 /* 3411 * Virtual page tables may need to update the accessed (A) bit 3412 * in a page table entry. Upgrade the fault to a write fault for 3413 * that case if the map will support it. If the map does not support 3414 * it the page table entry simply will not be updated. 3415 */ 3416 if (entry->maptype == VM_MAPTYPE_VPAGETABLE) { 3417 if (prot & VM_PROT_WRITE) 3418 fault_type |= VM_PROT_WRITE; 3419 } 3420 3421 /* 3422 * If the entry was copy-on-write, we either ... 3423 */ 3424 if (entry->eflags & MAP_ENTRY_NEEDS_COPY) { 3425 /* 3426 * If we want to write the page, we may as well handle that 3427 * now since we've got the map locked. 3428 * 3429 * If we don't need to write the page, we just demote the 3430 * permissions allowed. 3431 */ 3432 3433 if (fault_type & VM_PROT_WRITE) { 3434 /* 3435 * Make a new object, and place it in the object 3436 * chain. Note that no new references have appeared 3437 * -- one just moved from the map to the new 3438 * object. 3439 */ 3440 3441 if (use_read_lock && vm_map_lock_upgrade(map)) { 3442 use_read_lock = 0; 3443 goto RetryLookup; 3444 } 3445 use_read_lock = 0; 3446 3447 vm_map_entry_shadow(entry); 3448 } else { 3449 /* 3450 * We're attempting to read a copy-on-write page -- 3451 * don't allow writes. 3452 */ 3453 3454 prot &= ~VM_PROT_WRITE; 3455 } 3456 } 3457 3458 /* 3459 * Create an object if necessary. 3460 */ 3461 if (entry->object.vm_object == NULL && 3462 !map->system_map) { 3463 if (use_read_lock && vm_map_lock_upgrade(map)) { 3464 use_read_lock = 0; 3465 goto RetryLookup; 3466 } 3467 use_read_lock = 0; 3468 vm_map_entry_allocate_object(entry); 3469 } 3470 3471 /* 3472 * Return the object/offset from this entry. If the entry was 3473 * copy-on-write or empty, it has been fixed up. 3474 */ 3475 3476 *pindex = OFF_TO_IDX((vaddr - entry->start) + entry->offset); 3477 *object = entry->object.vm_object; 3478 3479 /* 3480 * Return whether this is the only map sharing this data. On 3481 * success we return with a read lock held on the map. On failure 3482 * we return with the map unlocked. 3483 */ 3484 *out_prot = prot; 3485 done: 3486 if (rv == KERN_SUCCESS) { 3487 if (use_read_lock == 0) 3488 vm_map_lock_downgrade(map); 3489 } else if (use_read_lock) { 3490 vm_map_unlock_read(map); 3491 } else { 3492 vm_map_unlock(map); 3493 } 3494 return (rv); 3495 } 3496 3497 /* 3498 * vm_map_lookup_done: 3499 * 3500 * Releases locks acquired by a vm_map_lookup 3501 * (according to the handle returned by that lookup). 3502 */ 3503 3504 void 3505 vm_map_lookup_done(vm_map_t map, vm_map_entry_t entry, int count) 3506 { 3507 /* 3508 * Unlock the main-level map 3509 */ 3510 vm_map_unlock_read(map); 3511 if (count) 3512 vm_map_entry_release(count); 3513 } 3514 3515 #include "opt_ddb.h" 3516 #ifdef DDB 3517 #include <sys/kernel.h> 3518 3519 #include <ddb/ddb.h> 3520 3521 /* 3522 * vm_map_print: [ debug ] 3523 */ 3524 DB_SHOW_COMMAND(map, vm_map_print) 3525 { 3526 static int nlines; 3527 /* XXX convert args. */ 3528 vm_map_t map = (vm_map_t)addr; 3529 boolean_t full = have_addr; 3530 3531 vm_map_entry_t entry; 3532 3533 db_iprintf("Task map %p: pmap=%p, nentries=%d, version=%u\n", 3534 (void *)map, 3535 (void *)map->pmap, map->nentries, map->timestamp); 3536 nlines++; 3537 3538 if (!full && db_indent) 3539 return; 3540 3541 db_indent += 2; 3542 for (entry = map->header.next; entry != &map->header; 3543 entry = entry->next) { 3544 db_iprintf("map entry %p: start=%p, end=%p\n", 3545 (void *)entry, (void *)entry->start, (void *)entry->end); 3546 nlines++; 3547 { 3548 static char *inheritance_name[4] = 3549 {"share", "copy", "none", "donate_copy"}; 3550 3551 db_iprintf(" prot=%x/%x/%s", 3552 entry->protection, 3553 entry->max_protection, 3554 inheritance_name[(int)(unsigned char)entry->inheritance]); 3555 if (entry->wired_count != 0) 3556 db_printf(", wired"); 3557 } 3558 if (entry->maptype == VM_MAPTYPE_SUBMAP) { 3559 /* XXX no %qd in kernel. Truncate entry->offset. */ 3560 db_printf(", share=%p, offset=0x%lx\n", 3561 (void *)entry->object.sub_map, 3562 (long)entry->offset); 3563 nlines++; 3564 if ((entry->prev == &map->header) || 3565 (entry->prev->object.sub_map != 3566 entry->object.sub_map)) { 3567 db_indent += 2; 3568 vm_map_print((db_expr_t)(intptr_t) 3569 entry->object.sub_map, 3570 full, 0, (char *)0); 3571 db_indent -= 2; 3572 } 3573 } else { 3574 /* XXX no %qd in kernel. Truncate entry->offset. */ 3575 db_printf(", object=%p, offset=0x%lx", 3576 (void *)entry->object.vm_object, 3577 (long)entry->offset); 3578 if (entry->eflags & MAP_ENTRY_COW) 3579 db_printf(", copy (%s)", 3580 (entry->eflags & MAP_ENTRY_NEEDS_COPY) ? "needed" : "done"); 3581 db_printf("\n"); 3582 nlines++; 3583 3584 if ((entry->prev == &map->header) || 3585 (entry->prev->object.vm_object != 3586 entry->object.vm_object)) { 3587 db_indent += 2; 3588 vm_object_print((db_expr_t)(intptr_t) 3589 entry->object.vm_object, 3590 full, 0, (char *)0); 3591 nlines += 4; 3592 db_indent -= 2; 3593 } 3594 } 3595 } 3596 db_indent -= 2; 3597 if (db_indent == 0) 3598 nlines = 0; 3599 } 3600 3601 3602 DB_SHOW_COMMAND(procvm, procvm) 3603 { 3604 struct proc *p; 3605 3606 if (have_addr) { 3607 p = (struct proc *) addr; 3608 } else { 3609 p = curproc; 3610 } 3611 3612 db_printf("p = %p, vmspace = %p, map = %p, pmap = %p\n", 3613 (void *)p, (void *)p->p_vmspace, (void *)&p->p_vmspace->vm_map, 3614 (void *)vmspace_pmap(p->p_vmspace)); 3615 3616 vm_map_print((db_expr_t)(intptr_t)&p->p_vmspace->vm_map, 1, 0, NULL); 3617 } 3618 3619 #endif /* DDB */ 3620