1 /* 2 * (MPSAFE) 3 * 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * The Mach Operating System project at Carnegie-Mellon University. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * from: @(#)vm_object.c 8.5 (Berkeley) 3/22/94 39 * 40 * 41 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 42 * All rights reserved. 43 * 44 * Authors: Avadis Tevanian, Jr., Michael Wayne Young 45 * 46 * Permission to use, copy, modify and distribute this software and 47 * its documentation is hereby granted, provided that both the copyright 48 * notice and this permission notice appear in all copies of the 49 * software, derivative works or modified versions, and any portions 50 * thereof, and that both notices appear in supporting documentation. 51 * 52 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 53 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 54 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 55 * 56 * Carnegie Mellon requests users of this software to return to 57 * 58 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 59 * School of Computer Science 60 * Carnegie Mellon University 61 * Pittsburgh PA 15213-3890 62 * 63 * any improvements or extensions that they make and grant Carnegie the 64 * rights to redistribute these changes. 65 * 66 * $FreeBSD: src/sys/vm/vm_object.c,v 1.171.2.8 2003/05/26 19:17:56 alc Exp $ 67 */ 68 69 /* 70 * Virtual memory object module. 71 */ 72 73 #include <sys/param.h> 74 #include <sys/systm.h> 75 #include <sys/proc.h> /* for curproc, pageproc */ 76 #include <sys/thread.h> 77 #include <sys/vnode.h> 78 #include <sys/vmmeter.h> 79 #include <sys/mman.h> 80 #include <sys/mount.h> 81 #include <sys/kernel.h> 82 #include <sys/sysctl.h> 83 #include <sys/refcount.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_object.h> 90 #include <vm/vm_page.h> 91 #include <vm/vm_pageout.h> 92 #include <vm/vm_pager.h> 93 #include <vm/swap_pager.h> 94 #include <vm/vm_kern.h> 95 #include <vm/vm_extern.h> 96 #include <vm/vm_zone.h> 97 98 #define EASY_SCAN_FACTOR 8 99 100 static void vm_object_qcollapse(vm_object_t object); 101 static int vm_object_page_collect_flush(vm_object_t object, vm_page_t p, 102 int pagerflags); 103 static void vm_object_lock_init(vm_object_t); 104 static void vm_object_hold_wait(vm_object_t); 105 106 107 /* 108 * Virtual memory objects maintain the actual data 109 * associated with allocated virtual memory. A given 110 * page of memory exists within exactly one object. 111 * 112 * An object is only deallocated when all "references" 113 * are given up. Only one "reference" to a given 114 * region of an object should be writeable. 115 * 116 * Associated with each object is a list of all resident 117 * memory pages belonging to that object; this list is 118 * maintained by the "vm_page" module, and locked by the object's 119 * lock. 120 * 121 * Each object also records a "pager" routine which is 122 * used to retrieve (and store) pages to the proper backing 123 * storage. In addition, objects may be backed by other 124 * objects from which they were virtual-copied. 125 * 126 * The only items within the object structure which are 127 * modified after time of creation are: 128 * reference count locked by object's lock 129 * pager routine locked by object's lock 130 * 131 */ 132 133 struct object_q vm_object_list; /* locked by vmobj_token */ 134 struct vm_object kernel_object; 135 136 static long vm_object_count; /* locked by vmobj_token */ 137 extern int vm_pageout_page_count; 138 139 static long object_collapses; 140 static long object_bypasses; 141 static int next_index; 142 static vm_zone_t obj_zone; 143 static struct vm_zone obj_zone_store; 144 #define VM_OBJECTS_INIT 256 145 static struct vm_object vm_objects_init[VM_OBJECTS_INIT]; 146 147 /* 148 * Misc low level routines 149 */ 150 static void 151 vm_object_lock_init(vm_object_t obj) 152 { 153 #if defined(DEBUG_LOCKS) 154 int i; 155 156 obj->debug_hold_bitmap = 0; 157 obj->debug_hold_ovfl = 0; 158 for (i = 0; i < VMOBJ_DEBUG_ARRAY_SIZE; i++) { 159 obj->debug_hold_thrs[i] = NULL; 160 obj->debug_hold_file[i] = NULL; 161 obj->debug_hold_line[i] = 0; 162 } 163 #endif 164 } 165 166 void 167 vm_object_lock_swap(void) 168 { 169 lwkt_token_swap(); 170 } 171 172 void 173 vm_object_lock(vm_object_t obj) 174 { 175 lwkt_getpooltoken(obj); 176 } 177 178 void 179 vm_object_unlock(vm_object_t obj) 180 { 181 lwkt_relpooltoken(obj); 182 } 183 184 static __inline void 185 vm_object_assert_held(vm_object_t obj) 186 { 187 ASSERT_LWKT_TOKEN_HELD(lwkt_token_pool_lookup(obj)); 188 } 189 190 void 191 #ifndef DEBUG_LOCKS 192 vm_object_hold(vm_object_t obj) 193 #else 194 debugvm_object_hold(vm_object_t obj, char *file, int line) 195 #endif 196 { 197 if (obj == NULL) 198 return; 199 200 /* 201 * Object must be held (object allocation is stable due to callers 202 * context, typically already holding the token on a parent object) 203 * prior to potentially blocking on the lock, otherwise the object 204 * can get ripped away from us. 205 */ 206 refcount_acquire(&obj->hold_count); 207 vm_object_lock(obj); 208 209 #if defined(DEBUG_LOCKS) 210 int i; 211 212 i = ffs(~obj->debug_hold_bitmap) - 1; 213 if (i == -1) { 214 kprintf("vm_object hold count > VMOBJ_DEBUG_ARRAY_SIZE"); 215 obj->debug_hold_ovfl = 1; 216 } 217 218 obj->debug_hold_bitmap |= (1 << i); 219 obj->debug_hold_thrs[i] = curthread; 220 obj->debug_hold_file[i] = file; 221 obj->debug_hold_line[i] = line; 222 #endif 223 } 224 225 void 226 vm_object_drop(vm_object_t obj) 227 { 228 if (obj == NULL) 229 return; 230 231 #if defined(DEBUG_LOCKS) 232 int found = 0; 233 int i; 234 235 for (i = 0; i < VMOBJ_DEBUG_ARRAY_SIZE; i++) { 236 if ((obj->debug_hold_bitmap & (1 << i)) && 237 (obj->debug_hold_thrs[i] == curthread)) { 238 obj->debug_hold_bitmap &= ~(1 << i); 239 obj->debug_hold_thrs[i] = NULL; 240 obj->debug_hold_file[i] = NULL; 241 obj->debug_hold_line[i] = 0; 242 found = 1; 243 break; 244 } 245 } 246 247 if (found == 0 && obj->debug_hold_ovfl == 0) 248 panic("vm_object: attempt to drop hold on non-self-held obj"); 249 #endif 250 251 /* 252 * The lock is a pool token, keep holding it across potential 253 * wakeups to interlock the tsleep/wakeup. 254 */ 255 if (refcount_release(&obj->hold_count)) 256 wakeup(obj); 257 vm_object_unlock(obj); 258 } 259 260 /* 261 * This can only be called while the caller holds the object 262 * with the OBJ_DEAD interlock. Since there are no refs this 263 * is the only thing preventing an object destruction race. 264 */ 265 static void 266 vm_object_hold_wait(vm_object_t obj) 267 { 268 vm_object_lock(obj); 269 270 #if defined(DEBUG_LOCKS) 271 int i; 272 273 for (i = 0; i < VMOBJ_DEBUG_ARRAY_SIZE; i++) { 274 if ((obj->debug_hold_bitmap & (1 << i)) && 275 (obj->debug_hold_thrs[i] == curthread)) { 276 kprintf("vm_object %p: self-hold in at %s:%d\n", obj, 277 obj->debug_hold_file[i], obj->debug_hold_line[i]); 278 panic("vm_object: self-hold in terminate or collapse"); 279 } 280 } 281 #endif 282 283 while (obj->hold_count) 284 tsleep(obj, 0, "vmobjhld", 0); 285 286 vm_object_unlock(obj); 287 } 288 289 290 /* 291 * Initialize a freshly allocated object 292 * 293 * Used only by vm_object_allocate() and zinitna(). 294 * 295 * No requirements. 296 */ 297 void 298 _vm_object_allocate(objtype_t type, vm_pindex_t size, vm_object_t object) 299 { 300 int incr; 301 302 RB_INIT(&object->rb_memq); 303 LIST_INIT(&object->shadow_head); 304 305 object->type = type; 306 object->size = size; 307 object->ref_count = 1; 308 object->hold_count = 0; 309 object->flags = 0; 310 if ((object->type == OBJT_DEFAULT) || (object->type == OBJT_SWAP)) 311 vm_object_set_flag(object, OBJ_ONEMAPPING); 312 object->paging_in_progress = 0; 313 object->resident_page_count = 0; 314 object->agg_pv_list_count = 0; 315 object->shadow_count = 0; 316 object->pg_color = next_index; 317 if ( size > (PQ_L2_SIZE / 3 + PQ_PRIME1)) 318 incr = PQ_L2_SIZE / 3 + PQ_PRIME1; 319 else 320 incr = size; 321 next_index = (next_index + incr) & PQ_L2_MASK; 322 object->handle = NULL; 323 object->backing_object = NULL; 324 object->backing_object_offset = (vm_ooffset_t) 0; 325 326 object->generation++; 327 object->swblock_count = 0; 328 RB_INIT(&object->swblock_root); 329 vm_object_lock_init(object); 330 331 lwkt_gettoken(&vmobj_token); 332 TAILQ_INSERT_TAIL(&vm_object_list, object, object_list); 333 vm_object_count++; 334 lwkt_reltoken(&vmobj_token); 335 } 336 337 /* 338 * Initialize the VM objects module. 339 * 340 * Called from the low level boot code only. 341 */ 342 void 343 vm_object_init(void) 344 { 345 TAILQ_INIT(&vm_object_list); 346 347 _vm_object_allocate(OBJT_DEFAULT, OFF_TO_IDX(KvaEnd), 348 &kernel_object); 349 350 obj_zone = &obj_zone_store; 351 zbootinit(obj_zone, "VM OBJECT", sizeof (struct vm_object), 352 vm_objects_init, VM_OBJECTS_INIT); 353 } 354 355 void 356 vm_object_init2(void) 357 { 358 zinitna(obj_zone, NULL, NULL, 0, 0, ZONE_PANICFAIL, 1); 359 } 360 361 /* 362 * Allocate and return a new object of the specified type and size. 363 * 364 * No requirements. 365 */ 366 vm_object_t 367 vm_object_allocate(objtype_t type, vm_pindex_t size) 368 { 369 vm_object_t result; 370 371 result = (vm_object_t) zalloc(obj_zone); 372 373 _vm_object_allocate(type, size, result); 374 375 return (result); 376 } 377 378 /* 379 * Add an additional reference to a vm_object. 380 * 381 * Object passed by caller must be stable or caller must already 382 * hold vmobj_token to avoid races. 383 */ 384 void 385 vm_object_reference(vm_object_t object) 386 { 387 lwkt_gettoken(&vmobj_token); 388 vm_object_hold(object); 389 vm_object_reference_locked(object); 390 vm_object_drop(object); 391 lwkt_reltoken(&vmobj_token); 392 } 393 394 void 395 vm_object_reference_locked(vm_object_t object) 396 { 397 if (object) { 398 ASSERT_LWKT_TOKEN_HELD(&vmobj_token); 399 /*NOTYET*/ 400 /*ASSERT_LWKT_TOKEN_HELD(vm_object_token(object));*/ 401 object->ref_count++; 402 if (object->type == OBJT_VNODE) { 403 vref(object->handle); 404 /* XXX what if the vnode is being destroyed? */ 405 } 406 } 407 } 408 409 /* 410 * Dereference an object and its underlying vnode. 411 * 412 * The caller must hold vmobj_token. 413 * The object must be locked but not held. This function will eat the lock. 414 */ 415 static void 416 vm_object_vndeallocate(vm_object_t object) 417 { 418 struct vnode *vp = (struct vnode *) object->handle; 419 420 KASSERT(object->type == OBJT_VNODE, 421 ("vm_object_vndeallocate: not a vnode object")); 422 KASSERT(vp != NULL, ("vm_object_vndeallocate: missing vp")); 423 ASSERT_LWKT_TOKEN_HELD(&vmobj_token); 424 #ifdef INVARIANTS 425 if (object->ref_count == 0) { 426 vprint("vm_object_vndeallocate", vp); 427 panic("vm_object_vndeallocate: bad object reference count"); 428 } 429 #endif 430 431 object->ref_count--; 432 if (object->ref_count == 0) 433 vclrflags(vp, VTEXT); 434 vm_object_unlock(object); 435 vrele(vp); 436 } 437 438 /* 439 * Release a reference to the specified object, gained either through a 440 * vm_object_allocate or a vm_object_reference call. When all references 441 * are gone, storage associated with this object may be relinquished. 442 * 443 * The caller does not have to hold the object locked but must have control 444 * over the reference in question in order to guarantee that the object 445 * does not get ripped out from under us. 446 */ 447 void 448 vm_object_deallocate(vm_object_t object) 449 { 450 lwkt_gettoken(&vmobj_token); 451 vm_object_deallocate_locked(object); 452 lwkt_reltoken(&vmobj_token); 453 } 454 455 void 456 vm_object_deallocate_locked(vm_object_t object) 457 { 458 vm_object_t temp; 459 460 ASSERT_LWKT_TOKEN_HELD(&vmobj_token); 461 462 if (object) 463 vm_object_lock(object); 464 465 while (object != NULL) { 466 if (object->type == OBJT_VNODE) { 467 vm_object_vndeallocate(object); 468 /* vndeallocate ate the lock */ 469 break; 470 } 471 472 if (object->ref_count == 0) { 473 panic("vm_object_deallocate: object deallocated " 474 "too many times: %d", object->type); 475 } 476 if (object->ref_count > 2) { 477 object->ref_count--; 478 vm_object_unlock(object); 479 break; 480 } 481 482 /* 483 * We currently need the vm_token from this point on, and 484 * we must recheck ref_count after acquiring it. 485 */ 486 lwkt_gettoken(&vm_token); 487 488 if (object->ref_count > 2) { 489 object->ref_count--; 490 lwkt_reltoken(&vm_token); 491 vm_object_unlock(object); 492 break; 493 } 494 495 /* 496 * Here on ref_count of one or two, which are special cases for 497 * objects. 498 * 499 * Nominal ref_count > 1 case if the second ref is not from 500 * a shadow. 501 */ 502 if (object->ref_count == 2 && object->shadow_count == 0) { 503 vm_object_set_flag(object, OBJ_ONEMAPPING); 504 object->ref_count--; 505 lwkt_reltoken(&vm_token); 506 vm_object_unlock(object); 507 break; 508 } 509 510 /* 511 * If the second ref is from a shadow we chain along it 512 * if object's handle is exhausted. 513 * 514 * We have to decrement object->ref_count before potentially 515 * collapsing the first shadow object or the collapse code 516 * will not be able to handle the degenerate case. 517 */ 518 if (object->ref_count == 2 && object->shadow_count == 1) { 519 object->ref_count--; 520 if (object->handle == NULL && 521 (object->type == OBJT_DEFAULT || 522 object->type == OBJT_SWAP)) { 523 temp = LIST_FIRST(&object->shadow_head); 524 KASSERT(temp != NULL, 525 ("vm_object_deallocate: ref_count: " 526 "%d, shadow_count: %d", 527 object->ref_count, 528 object->shadow_count)); 529 lwkt_reltoken(&vm_token); 530 vm_object_lock(temp); 531 532 if ((temp->handle == NULL) && 533 (temp->type == OBJT_DEFAULT || 534 temp->type == OBJT_SWAP)) { 535 /* 536 * Special case, must handle ref_count 537 * manually to avoid recursion. 538 */ 539 temp->ref_count++; 540 vm_object_lock_swap(); 541 542 while ( 543 temp->paging_in_progress || 544 object->paging_in_progress 545 ) { 546 vm_object_pip_wait(temp, 547 "objde1"); 548 vm_object_pip_wait(object, 549 "objde2"); 550 } 551 552 if (temp->ref_count == 1) { 553 temp->ref_count--; 554 vm_object_unlock(object); 555 object = temp; 556 goto doterm; 557 } 558 559 lwkt_gettoken(&vm_token); 560 vm_object_collapse(temp); 561 lwkt_reltoken(&vm_token); 562 vm_object_unlock(object); 563 object = temp; 564 continue; 565 } 566 vm_object_unlock(temp); 567 } else { 568 lwkt_reltoken(&vm_token); 569 } 570 vm_object_unlock(object); 571 break; 572 } 573 574 /* 575 * Normal dereferencing path 576 */ 577 object->ref_count--; 578 if (object->ref_count != 0) { 579 lwkt_reltoken(&vm_token); 580 vm_object_unlock(object); 581 break; 582 } 583 584 /* 585 * Termination path 586 * 587 * We may have to loop to resolve races if we block getting 588 * temp's lock. If temp is non NULL we have to swap the 589 * lock order so the original object lock as at the top 590 * of the lock heap. 591 */ 592 lwkt_reltoken(&vm_token); 593 doterm: 594 while ((temp = object->backing_object) != NULL) { 595 vm_object_lock(temp); 596 if (temp == object->backing_object) 597 break; 598 vm_object_unlock(temp); 599 } 600 if (temp) { 601 LIST_REMOVE(object, shadow_list); 602 temp->shadow_count--; 603 temp->generation++; 604 object->backing_object = NULL; 605 vm_object_lock_swap(); 606 } 607 608 /* 609 * Don't double-terminate, we could be in a termination 610 * recursion due to the terminate having to sync data 611 * to disk. 612 */ 613 if ((object->flags & OBJ_DEAD) == 0) { 614 vm_object_terminate(object); 615 /* termination ate the object lock */ 616 } else { 617 vm_object_unlock(object); 618 } 619 object = temp; 620 } 621 } 622 623 /* 624 * Destroy the specified object, freeing up related resources. 625 * 626 * The object must have zero references. 627 * 628 * The caller must be holding vmobj_token and properly interlock with 629 * OBJ_DEAD (at the moment). 630 * 631 * The caller must have locked the object only, and not be holding it. 632 * This function will eat the caller's lock on the object. 633 */ 634 static int vm_object_terminate_callback(vm_page_t p, void *data); 635 636 void 637 vm_object_terminate(vm_object_t object) 638 { 639 /* 640 * Make sure no one uses us. Once we set OBJ_DEAD we should be 641 * able to safely block. 642 */ 643 KKASSERT((object->flags & OBJ_DEAD) == 0); 644 ASSERT_LWKT_TOKEN_HELD(&vmobj_token); 645 vm_object_set_flag(object, OBJ_DEAD); 646 647 /* 648 * Wait for the pageout daemon to be done with the object 649 */ 650 vm_object_pip_wait(object, "objtrm1"); 651 652 KASSERT(!object->paging_in_progress, 653 ("vm_object_terminate: pageout in progress")); 654 655 /* 656 * Clean and free the pages, as appropriate. All references to the 657 * object are gone, so we don't need to lock it. 658 */ 659 if (object->type == OBJT_VNODE) { 660 struct vnode *vp; 661 662 /* 663 * Clean pages and flush buffers. 664 */ 665 vm_object_page_clean(object, 0, 0, OBJPC_SYNC); 666 667 vp = (struct vnode *) object->handle; 668 vinvalbuf(vp, V_SAVE, 0, 0); 669 } 670 671 /* 672 * Wait for any I/O to complete, after which there had better not 673 * be any references left on the object. 674 */ 675 vm_object_pip_wait(object, "objtrm2"); 676 677 if (object->ref_count != 0) { 678 panic("vm_object_terminate: object with references, " 679 "ref_count=%d", object->ref_count); 680 } 681 682 /* 683 * Now free any remaining pages. For internal objects, this also 684 * removes them from paging queues. Don't free wired pages, just 685 * remove them from the object. 686 */ 687 lwkt_gettoken(&vm_token); 688 vm_page_rb_tree_RB_SCAN(&object->rb_memq, NULL, 689 vm_object_terminate_callback, NULL); 690 lwkt_reltoken(&vm_token); 691 692 /* 693 * Let the pager know object is dead. 694 */ 695 vm_pager_deallocate(object); 696 697 /* 698 * Wait for the object hold count to hit zero, clean out pages as 699 * we go. 700 */ 701 lwkt_gettoken(&vm_token); 702 for (;;) { 703 vm_object_hold_wait(object); 704 if (RB_ROOT(&object->rb_memq) == NULL) 705 break; 706 kprintf("vm_object_terminate: Warning, object %p " 707 "still has %d pages\n", 708 object, object->resident_page_count); 709 vm_page_rb_tree_RB_SCAN(&object->rb_memq, NULL, 710 vm_object_terminate_callback, NULL); 711 } 712 lwkt_reltoken(&vm_token); 713 714 /* 715 * There had better not be any pages left 716 */ 717 KKASSERT(object->resident_page_count == 0); 718 719 /* 720 * Remove the object from the global object list. 721 * 722 * (we are holding vmobj_token) 723 */ 724 TAILQ_REMOVE(&vm_object_list, object, object_list); 725 vm_object_count--; 726 vm_object_dead_wakeup(object); 727 vm_object_unlock(object); 728 729 if (object->ref_count != 0) { 730 panic("vm_object_terminate2: object with references, " 731 "ref_count=%d", object->ref_count); 732 } 733 734 /* 735 * Free the space for the object. 736 */ 737 zfree(obj_zone, object); 738 } 739 740 /* 741 * The caller must hold vm_token. 742 */ 743 static int 744 vm_object_terminate_callback(vm_page_t p, void *data __unused) 745 { 746 if (p->busy || (p->flags & PG_BUSY)) 747 panic("vm_object_terminate: freeing busy page %p", p); 748 if (p->wire_count == 0) { 749 vm_page_busy(p); 750 vm_page_free(p); 751 mycpu->gd_cnt.v_pfree++; 752 } else { 753 if (p->queue != PQ_NONE) 754 kprintf("vm_object_terminate: Warning: Encountered wired page %p on queue %d\n", p, p->queue); 755 vm_page_busy(p); 756 vm_page_remove(p); 757 vm_page_wakeup(p); 758 } 759 return(0); 760 } 761 762 /* 763 * The object is dead but still has an object<->pager association. Sleep 764 * and return. The caller typically retests the association in a loop. 765 * 766 * Must be called with the vmobj_token held. 767 */ 768 void 769 vm_object_dead_sleep(vm_object_t object, const char *wmesg) 770 { 771 ASSERT_LWKT_TOKEN_HELD(&vmobj_token); 772 if (object->handle) { 773 vm_object_set_flag(object, OBJ_DEADWNT); 774 tsleep(object, 0, wmesg, 0); 775 /* object may be invalid after this point */ 776 } 777 } 778 779 /* 780 * Wakeup anyone waiting for the object<->pager disassociation on 781 * a dead object. 782 * 783 * Must be called with the vmobj_token held. 784 */ 785 void 786 vm_object_dead_wakeup(vm_object_t object) 787 { 788 ASSERT_LWKT_TOKEN_HELD(&vmobj_token); 789 if (object->flags & OBJ_DEADWNT) { 790 vm_object_clear_flag(object, OBJ_DEADWNT); 791 wakeup(object); 792 } 793 } 794 795 /* 796 * Clean all dirty pages in the specified range of object. Leaves page 797 * on whatever queue it is currently on. If NOSYNC is set then do not 798 * write out pages with PG_NOSYNC set (originally comes from MAP_NOSYNC), 799 * leaving the object dirty. 800 * 801 * When stuffing pages asynchronously, allow clustering. XXX we need a 802 * synchronous clustering mode implementation. 803 * 804 * Odd semantics: if start == end, we clean everything. 805 * 806 * The object must be locked? XXX 807 */ 808 static int vm_object_page_clean_pass1(struct vm_page *p, void *data); 809 static int vm_object_page_clean_pass2(struct vm_page *p, void *data); 810 811 void 812 vm_object_page_clean(vm_object_t object, vm_pindex_t start, vm_pindex_t end, 813 int flags) 814 { 815 struct rb_vm_page_scan_info info; 816 struct vnode *vp; 817 int wholescan; 818 int pagerflags; 819 int curgeneration; 820 821 vm_object_hold(object); 822 if (object->type != OBJT_VNODE || 823 (object->flags & OBJ_MIGHTBEDIRTY) == 0) { 824 vm_object_drop(object); 825 return; 826 } 827 828 pagerflags = (flags & (OBJPC_SYNC | OBJPC_INVAL)) ? 829 VM_PAGER_PUT_SYNC : VM_PAGER_CLUSTER_OK; 830 pagerflags |= (flags & OBJPC_INVAL) ? VM_PAGER_PUT_INVAL : 0; 831 832 vp = object->handle; 833 834 /* 835 * Interlock other major object operations. This allows us to 836 * temporarily clear OBJ_WRITEABLE and OBJ_MIGHTBEDIRTY. 837 */ 838 crit_enter(); 839 vm_object_set_flag(object, OBJ_CLEANING); 840 841 /* 842 * Handle 'entire object' case 843 */ 844 info.start_pindex = start; 845 if (end == 0) { 846 info.end_pindex = object->size - 1; 847 } else { 848 info.end_pindex = end - 1; 849 } 850 wholescan = (start == 0 && info.end_pindex == object->size - 1); 851 info.limit = flags; 852 info.pagerflags = pagerflags; 853 info.object = object; 854 855 /* 856 * If cleaning the entire object do a pass to mark the pages read-only. 857 * If everything worked out ok, clear OBJ_WRITEABLE and 858 * OBJ_MIGHTBEDIRTY. 859 */ 860 if (wholescan) { 861 info.error = 0; 862 lwkt_gettoken(&vm_token); 863 vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp, 864 vm_object_page_clean_pass1, &info); 865 lwkt_reltoken(&vm_token); 866 if (info.error == 0) { 867 vm_object_clear_flag(object, 868 OBJ_WRITEABLE|OBJ_MIGHTBEDIRTY); 869 if (object->type == OBJT_VNODE && 870 (vp = (struct vnode *)object->handle) != NULL) { 871 if (vp->v_flag & VOBJDIRTY) 872 vclrflags(vp, VOBJDIRTY); 873 } 874 } 875 } 876 877 /* 878 * Do a pass to clean all the dirty pages we find. 879 */ 880 do { 881 info.error = 0; 882 curgeneration = object->generation; 883 lwkt_gettoken(&vm_token); 884 vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp, 885 vm_object_page_clean_pass2, &info); 886 lwkt_reltoken(&vm_token); 887 } while (info.error || curgeneration != object->generation); 888 889 vm_object_clear_flag(object, OBJ_CLEANING); 890 crit_exit(); 891 vm_object_drop(object); 892 } 893 894 /* 895 * The caller must hold vm_token. 896 */ 897 static 898 int 899 vm_object_page_clean_pass1(struct vm_page *p, void *data) 900 { 901 struct rb_vm_page_scan_info *info = data; 902 903 vm_page_flag_set(p, PG_CLEANCHK); 904 if ((info->limit & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC)) 905 info->error = 1; 906 else 907 vm_page_protect(p, VM_PROT_READ); /* must not block */ 908 return(0); 909 } 910 911 /* 912 * The caller must hold vm_token. 913 */ 914 static 915 int 916 vm_object_page_clean_pass2(struct vm_page *p, void *data) 917 { 918 struct rb_vm_page_scan_info *info = data; 919 int n; 920 921 /* 922 * Do not mess with pages that were inserted after we started 923 * the cleaning pass. 924 */ 925 if ((p->flags & PG_CLEANCHK) == 0) 926 return(0); 927 928 /* 929 * Before wasting time traversing the pmaps, check for trivial 930 * cases where the page cannot be dirty. 931 */ 932 if (p->valid == 0 || (p->queue - p->pc) == PQ_CACHE) { 933 KKASSERT((p->dirty & p->valid) == 0); 934 return(0); 935 } 936 937 /* 938 * Check whether the page is dirty or not. The page has been set 939 * to be read-only so the check will not race a user dirtying the 940 * page. 941 */ 942 vm_page_test_dirty(p); 943 if ((p->dirty & p->valid) == 0) { 944 vm_page_flag_clear(p, PG_CLEANCHK); 945 return(0); 946 } 947 948 /* 949 * If we have been asked to skip nosync pages and this is a 950 * nosync page, skip it. Note that the object flags were 951 * not cleared in this case (because pass1 will have returned an 952 * error), so we do not have to set them. 953 */ 954 if ((info->limit & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC)) { 955 vm_page_flag_clear(p, PG_CLEANCHK); 956 return(0); 957 } 958 959 /* 960 * Flush as many pages as we can. PG_CLEANCHK will be cleared on 961 * the pages that get successfully flushed. Set info->error if 962 * we raced an object modification. 963 */ 964 n = vm_object_page_collect_flush(info->object, p, info->pagerflags); 965 if (n == 0) 966 info->error = 1; 967 return(0); 968 } 969 970 /* 971 * Collect the specified page and nearby pages and flush them out. 972 * The number of pages flushed is returned. 973 * 974 * The caller must hold vm_token. 975 */ 976 static int 977 vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int pagerflags) 978 { 979 int runlen; 980 int maxf; 981 int chkb; 982 int maxb; 983 int i; 984 int curgeneration; 985 vm_pindex_t pi; 986 vm_page_t maf[vm_pageout_page_count]; 987 vm_page_t mab[vm_pageout_page_count]; 988 vm_page_t ma[vm_pageout_page_count]; 989 990 curgeneration = object->generation; 991 992 pi = p->pindex; 993 while (vm_page_sleep_busy(p, TRUE, "vpcwai")) { 994 if (object->generation != curgeneration) { 995 return(0); 996 } 997 } 998 KKASSERT(p->object == object && p->pindex == pi); 999 1000 maxf = 0; 1001 for(i = 1; i < vm_pageout_page_count; i++) { 1002 vm_page_t tp; 1003 1004 if ((tp = vm_page_lookup(object, pi + i)) != NULL) { 1005 if ((tp->flags & PG_BUSY) || 1006 ((pagerflags & VM_PAGER_IGNORE_CLEANCHK) == 0 && 1007 (tp->flags & PG_CLEANCHK) == 0) || 1008 (tp->busy != 0)) 1009 break; 1010 if((tp->queue - tp->pc) == PQ_CACHE) { 1011 vm_page_flag_clear(tp, PG_CLEANCHK); 1012 break; 1013 } 1014 vm_page_test_dirty(tp); 1015 if ((tp->dirty & tp->valid) == 0) { 1016 vm_page_flag_clear(tp, PG_CLEANCHK); 1017 break; 1018 } 1019 maf[ i - 1 ] = tp; 1020 maxf++; 1021 continue; 1022 } 1023 break; 1024 } 1025 1026 maxb = 0; 1027 chkb = vm_pageout_page_count - maxf; 1028 if (chkb) { 1029 for(i = 1; i < chkb;i++) { 1030 vm_page_t tp; 1031 1032 if ((tp = vm_page_lookup(object, pi - i)) != NULL) { 1033 if ((tp->flags & PG_BUSY) || 1034 ((pagerflags & VM_PAGER_IGNORE_CLEANCHK) == 0 && 1035 (tp->flags & PG_CLEANCHK) == 0) || 1036 (tp->busy != 0)) 1037 break; 1038 if((tp->queue - tp->pc) == PQ_CACHE) { 1039 vm_page_flag_clear(tp, PG_CLEANCHK); 1040 break; 1041 } 1042 vm_page_test_dirty(tp); 1043 if ((tp->dirty & tp->valid) == 0) { 1044 vm_page_flag_clear(tp, PG_CLEANCHK); 1045 break; 1046 } 1047 mab[ i - 1 ] = tp; 1048 maxb++; 1049 continue; 1050 } 1051 break; 1052 } 1053 } 1054 1055 for(i = 0; i < maxb; i++) { 1056 int index = (maxb - i) - 1; 1057 ma[index] = mab[i]; 1058 vm_page_flag_clear(ma[index], PG_CLEANCHK); 1059 } 1060 vm_page_flag_clear(p, PG_CLEANCHK); 1061 ma[maxb] = p; 1062 for(i = 0; i < maxf; i++) { 1063 int index = (maxb + i) + 1; 1064 ma[index] = maf[i]; 1065 vm_page_flag_clear(ma[index], PG_CLEANCHK); 1066 } 1067 runlen = maxb + maxf + 1; 1068 1069 vm_pageout_flush(ma, runlen, pagerflags); 1070 for (i = 0; i < runlen; i++) { 1071 if (ma[i]->valid & ma[i]->dirty) { 1072 vm_page_protect(ma[i], VM_PROT_READ); 1073 vm_page_flag_set(ma[i], PG_CLEANCHK); 1074 1075 /* 1076 * maxf will end up being the actual number of pages 1077 * we wrote out contiguously, non-inclusive of the 1078 * first page. We do not count look-behind pages. 1079 */ 1080 if (i >= maxb + 1 && (maxf > i - maxb - 1)) 1081 maxf = i - maxb - 1; 1082 } 1083 } 1084 return(maxf + 1); 1085 } 1086 1087 /* 1088 * Same as vm_object_pmap_copy, except range checking really 1089 * works, and is meant for small sections of an object. 1090 * 1091 * This code protects resident pages by making them read-only 1092 * and is typically called on a fork or split when a page 1093 * is converted to copy-on-write. 1094 * 1095 * NOTE: If the page is already at VM_PROT_NONE, calling 1096 * vm_page_protect will have no effect. 1097 */ 1098 void 1099 vm_object_pmap_copy_1(vm_object_t object, vm_pindex_t start, vm_pindex_t end) 1100 { 1101 vm_pindex_t idx; 1102 vm_page_t p; 1103 1104 if (object == NULL || (object->flags & OBJ_WRITEABLE) == 0) 1105 return; 1106 1107 /* 1108 * spl protection needed to prevent races between the lookup, 1109 * an interrupt unbusy/free, and our protect call. 1110 */ 1111 crit_enter(); 1112 lwkt_gettoken(&vm_token); 1113 for (idx = start; idx < end; idx++) { 1114 p = vm_page_lookup(object, idx); 1115 if (p == NULL) 1116 continue; 1117 vm_page_protect(p, VM_PROT_READ); 1118 } 1119 lwkt_reltoken(&vm_token); 1120 crit_exit(); 1121 } 1122 1123 /* 1124 * Removes all physical pages in the specified object range from all 1125 * physical maps. 1126 * 1127 * The object must *not* be locked. 1128 */ 1129 1130 static int vm_object_pmap_remove_callback(vm_page_t p, void *data); 1131 1132 void 1133 vm_object_pmap_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end) 1134 { 1135 struct rb_vm_page_scan_info info; 1136 1137 if (object == NULL) 1138 return; 1139 info.start_pindex = start; 1140 info.end_pindex = end - 1; 1141 1142 crit_enter(); 1143 lwkt_gettoken(&vm_token); 1144 vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp, 1145 vm_object_pmap_remove_callback, &info); 1146 if (start == 0 && end == object->size) 1147 vm_object_clear_flag(object, OBJ_WRITEABLE); 1148 lwkt_reltoken(&vm_token); 1149 crit_exit(); 1150 } 1151 1152 /* 1153 * The caller must hold vm_token. 1154 */ 1155 static int 1156 vm_object_pmap_remove_callback(vm_page_t p, void *data __unused) 1157 { 1158 vm_page_protect(p, VM_PROT_NONE); 1159 return(0); 1160 } 1161 1162 /* 1163 * Implements the madvise function at the object/page level. 1164 * 1165 * MADV_WILLNEED (any object) 1166 * 1167 * Activate the specified pages if they are resident. 1168 * 1169 * MADV_DONTNEED (any object) 1170 * 1171 * Deactivate the specified pages if they are resident. 1172 * 1173 * MADV_FREE (OBJT_DEFAULT/OBJT_SWAP objects, OBJ_ONEMAPPING only) 1174 * 1175 * Deactivate and clean the specified pages if they are 1176 * resident. This permits the process to reuse the pages 1177 * without faulting or the kernel to reclaim the pages 1178 * without I/O. 1179 * 1180 * No requirements. 1181 */ 1182 void 1183 vm_object_madvise(vm_object_t object, vm_pindex_t pindex, int count, int advise) 1184 { 1185 vm_pindex_t end, tpindex; 1186 vm_object_t tobject; 1187 vm_page_t m; 1188 1189 if (object == NULL) 1190 return; 1191 1192 end = pindex + count; 1193 1194 lwkt_gettoken(&vm_token); 1195 1196 /* 1197 * Locate and adjust resident pages 1198 */ 1199 for (; pindex < end; pindex += 1) { 1200 relookup: 1201 tobject = object; 1202 tpindex = pindex; 1203 shadowlookup: 1204 /* 1205 * MADV_FREE only operates on OBJT_DEFAULT or OBJT_SWAP pages 1206 * and those pages must be OBJ_ONEMAPPING. 1207 */ 1208 if (advise == MADV_FREE) { 1209 if ((tobject->type != OBJT_DEFAULT && 1210 tobject->type != OBJT_SWAP) || 1211 (tobject->flags & OBJ_ONEMAPPING) == 0) { 1212 continue; 1213 } 1214 } 1215 1216 /* 1217 * spl protection is required to avoid a race between the 1218 * lookup, an interrupt unbusy/free, and our busy check. 1219 */ 1220 1221 crit_enter(); 1222 m = vm_page_lookup(tobject, tpindex); 1223 1224 if (m == NULL) { 1225 /* 1226 * There may be swap even if there is no backing page 1227 */ 1228 if (advise == MADV_FREE && tobject->type == OBJT_SWAP) 1229 swap_pager_freespace(tobject, tpindex, 1); 1230 1231 /* 1232 * next object 1233 */ 1234 crit_exit(); 1235 if (tobject->backing_object == NULL) 1236 continue; 1237 tpindex += OFF_TO_IDX(tobject->backing_object_offset); 1238 tobject = tobject->backing_object; 1239 goto shadowlookup; 1240 } 1241 1242 /* 1243 * If the page is busy or not in a normal active state, 1244 * we skip it. If the page is not managed there are no 1245 * page queues to mess with. Things can break if we mess 1246 * with pages in any of the below states. 1247 */ 1248 if ( 1249 m->hold_count || 1250 m->wire_count || 1251 (m->flags & PG_UNMANAGED) || 1252 m->valid != VM_PAGE_BITS_ALL 1253 ) { 1254 crit_exit(); 1255 continue; 1256 } 1257 1258 if (vm_page_sleep_busy(m, TRUE, "madvpo")) { 1259 crit_exit(); 1260 goto relookup; 1261 } 1262 vm_page_busy(m); 1263 crit_exit(); 1264 1265 /* 1266 * Theoretically once a page is known not to be busy, an 1267 * interrupt cannot come along and rip it out from under us. 1268 */ 1269 1270 if (advise == MADV_WILLNEED) { 1271 vm_page_activate(m); 1272 } else if (advise == MADV_DONTNEED) { 1273 vm_page_dontneed(m); 1274 } else if (advise == MADV_FREE) { 1275 /* 1276 * Mark the page clean. This will allow the page 1277 * to be freed up by the system. However, such pages 1278 * are often reused quickly by malloc()/free() 1279 * so we do not do anything that would cause 1280 * a page fault if we can help it. 1281 * 1282 * Specifically, we do not try to actually free 1283 * the page now nor do we try to put it in the 1284 * cache (which would cause a page fault on reuse). 1285 * 1286 * But we do make the page is freeable as we 1287 * can without actually taking the step of unmapping 1288 * it. 1289 */ 1290 pmap_clear_modify(m); 1291 m->dirty = 0; 1292 m->act_count = 0; 1293 vm_page_dontneed(m); 1294 if (tobject->type == OBJT_SWAP) 1295 swap_pager_freespace(tobject, tpindex, 1); 1296 } 1297 vm_page_wakeup(m); 1298 } 1299 lwkt_reltoken(&vm_token); 1300 } 1301 1302 /* 1303 * Create a new object which is backed by the specified existing object 1304 * range. The source object reference is deallocated. 1305 * 1306 * The new object and offset into that object are returned in the source 1307 * parameters. 1308 * 1309 * No other requirements. 1310 */ 1311 void 1312 vm_object_shadow(vm_object_t *object, vm_ooffset_t *offset, vm_size_t length) 1313 { 1314 vm_object_t source; 1315 vm_object_t result; 1316 1317 source = *object; 1318 1319 /* 1320 * Don't create the new object if the old object isn't shared. 1321 */ 1322 lwkt_gettoken(&vm_token); 1323 1324 if (source != NULL && 1325 source->ref_count == 1 && 1326 source->handle == NULL && 1327 (source->type == OBJT_DEFAULT || 1328 source->type == OBJT_SWAP)) { 1329 lwkt_reltoken(&vm_token); 1330 return; 1331 } 1332 1333 /* 1334 * Allocate a new object with the given length 1335 */ 1336 1337 if ((result = vm_object_allocate(OBJT_DEFAULT, length)) == NULL) 1338 panic("vm_object_shadow: no object for shadowing"); 1339 1340 /* 1341 * The new object shadows the source object, adding a reference to it. 1342 * Our caller changes his reference to point to the new object, 1343 * removing a reference to the source object. Net result: no change 1344 * of reference count. 1345 * 1346 * Try to optimize the result object's page color when shadowing 1347 * in order to maintain page coloring consistency in the combined 1348 * shadowed object. 1349 */ 1350 result->backing_object = source; 1351 if (source) { 1352 LIST_INSERT_HEAD(&source->shadow_head, result, shadow_list); 1353 source->shadow_count++; 1354 source->generation++; 1355 result->pg_color = (source->pg_color + OFF_TO_IDX(*offset)) & PQ_L2_MASK; 1356 } 1357 1358 /* 1359 * Store the offset into the source object, and fix up the offset into 1360 * the new object. 1361 */ 1362 result->backing_object_offset = *offset; 1363 lwkt_reltoken(&vm_token); 1364 1365 /* 1366 * Return the new things 1367 */ 1368 *offset = 0; 1369 *object = result; 1370 } 1371 1372 #define OBSC_TEST_ALL_SHADOWED 0x0001 1373 #define OBSC_COLLAPSE_NOWAIT 0x0002 1374 #define OBSC_COLLAPSE_WAIT 0x0004 1375 1376 static int vm_object_backing_scan_callback(vm_page_t p, void *data); 1377 1378 /* 1379 * The caller must hold vm_token. 1380 */ 1381 static __inline int 1382 vm_object_backing_scan(vm_object_t object, int op) 1383 { 1384 struct rb_vm_page_scan_info info; 1385 vm_object_t backing_object; 1386 1387 crit_enter(); 1388 1389 backing_object = object->backing_object; 1390 info.backing_offset_index = OFF_TO_IDX(object->backing_object_offset); 1391 1392 /* 1393 * Initial conditions 1394 */ 1395 1396 if (op & OBSC_TEST_ALL_SHADOWED) { 1397 /* 1398 * We do not want to have to test for the existence of 1399 * swap pages in the backing object. XXX but with the 1400 * new swapper this would be pretty easy to do. 1401 * 1402 * XXX what about anonymous MAP_SHARED memory that hasn't 1403 * been ZFOD faulted yet? If we do not test for this, the 1404 * shadow test may succeed! XXX 1405 */ 1406 if (backing_object->type != OBJT_DEFAULT) { 1407 crit_exit(); 1408 return(0); 1409 } 1410 } 1411 if (op & OBSC_COLLAPSE_WAIT) { 1412 KKASSERT((backing_object->flags & OBJ_DEAD) == 0); 1413 vm_object_set_flag(backing_object, OBJ_DEAD); 1414 } 1415 1416 /* 1417 * Our scan. We have to retry if a negative error code is returned, 1418 * otherwise 0 or 1 will be returned in info.error. 0 Indicates that 1419 * the scan had to be stopped because the parent does not completely 1420 * shadow the child. 1421 */ 1422 info.object = object; 1423 info.backing_object = backing_object; 1424 info.limit = op; 1425 do { 1426 info.error = 1; 1427 vm_page_rb_tree_RB_SCAN(&backing_object->rb_memq, NULL, 1428 vm_object_backing_scan_callback, 1429 &info); 1430 } while (info.error < 0); 1431 crit_exit(); 1432 return(info.error); 1433 } 1434 1435 /* 1436 * The caller must hold vm_token. 1437 */ 1438 static int 1439 vm_object_backing_scan_callback(vm_page_t p, void *data) 1440 { 1441 struct rb_vm_page_scan_info *info = data; 1442 vm_object_t backing_object; 1443 vm_object_t object; 1444 vm_pindex_t new_pindex; 1445 vm_pindex_t backing_offset_index; 1446 int op; 1447 1448 new_pindex = p->pindex - info->backing_offset_index; 1449 op = info->limit; 1450 object = info->object; 1451 backing_object = info->backing_object; 1452 backing_offset_index = info->backing_offset_index; 1453 1454 if (op & OBSC_TEST_ALL_SHADOWED) { 1455 vm_page_t pp; 1456 1457 /* 1458 * Ignore pages outside the parent object's range 1459 * and outside the parent object's mapping of the 1460 * backing object. 1461 * 1462 * note that we do not busy the backing object's 1463 * page. 1464 */ 1465 if ( 1466 p->pindex < backing_offset_index || 1467 new_pindex >= object->size 1468 ) { 1469 return(0); 1470 } 1471 1472 /* 1473 * See if the parent has the page or if the parent's 1474 * object pager has the page. If the parent has the 1475 * page but the page is not valid, the parent's 1476 * object pager must have the page. 1477 * 1478 * If this fails, the parent does not completely shadow 1479 * the object and we might as well give up now. 1480 */ 1481 1482 pp = vm_page_lookup(object, new_pindex); 1483 if ((pp == NULL || pp->valid == 0) && 1484 !vm_pager_has_page(object, new_pindex) 1485 ) { 1486 info->error = 0; /* problemo */ 1487 return(-1); /* stop the scan */ 1488 } 1489 } 1490 1491 /* 1492 * Check for busy page 1493 */ 1494 1495 if (op & (OBSC_COLLAPSE_WAIT | OBSC_COLLAPSE_NOWAIT)) { 1496 vm_page_t pp; 1497 1498 if (op & OBSC_COLLAPSE_NOWAIT) { 1499 if ( 1500 (p->flags & PG_BUSY) || 1501 !p->valid || 1502 p->hold_count || 1503 p->wire_count || 1504 p->busy 1505 ) { 1506 return(0); 1507 } 1508 } else if (op & OBSC_COLLAPSE_WAIT) { 1509 if (vm_page_sleep_busy(p, TRUE, "vmocol")) { 1510 /* 1511 * If we slept, anything could have 1512 * happened. Ask that the scan be restarted. 1513 * 1514 * Since the object is marked dead, the 1515 * backing offset should not have changed. 1516 */ 1517 info->error = -1; 1518 return(-1); 1519 } 1520 } 1521 1522 /* 1523 * Busy the page 1524 */ 1525 vm_page_busy(p); 1526 1527 KASSERT( 1528 p->object == backing_object, 1529 ("vm_object_qcollapse(): object mismatch") 1530 ); 1531 1532 /* 1533 * Destroy any associated swap 1534 */ 1535 if (backing_object->type == OBJT_SWAP) 1536 swap_pager_freespace(backing_object, p->pindex, 1); 1537 1538 if ( 1539 p->pindex < backing_offset_index || 1540 new_pindex >= object->size 1541 ) { 1542 /* 1543 * Page is out of the parent object's range, we 1544 * can simply destroy it. 1545 */ 1546 vm_page_protect(p, VM_PROT_NONE); 1547 vm_page_free(p); 1548 return(0); 1549 } 1550 1551 pp = vm_page_lookup(object, new_pindex); 1552 if (pp != NULL || vm_pager_has_page(object, new_pindex)) { 1553 /* 1554 * page already exists in parent OR swap exists 1555 * for this location in the parent. Destroy 1556 * the original page from the backing object. 1557 * 1558 * Leave the parent's page alone 1559 */ 1560 vm_page_protect(p, VM_PROT_NONE); 1561 vm_page_free(p); 1562 return(0); 1563 } 1564 1565 /* 1566 * Page does not exist in parent, rename the 1567 * page from the backing object to the main object. 1568 * 1569 * If the page was mapped to a process, it can remain 1570 * mapped through the rename. 1571 */ 1572 if ((p->queue - p->pc) == PQ_CACHE) 1573 vm_page_deactivate(p); 1574 1575 vm_page_rename(p, object, new_pindex); 1576 /* page automatically made dirty by rename */ 1577 } 1578 return(0); 1579 } 1580 1581 /* 1582 * This version of collapse allows the operation to occur earlier and 1583 * when paging_in_progress is true for an object... This is not a complete 1584 * operation, but should plug 99.9% of the rest of the leaks. 1585 * 1586 * The caller must hold vm_token and vmobj_token. 1587 * (only called from vm_object_collapse) 1588 */ 1589 static void 1590 vm_object_qcollapse(vm_object_t object) 1591 { 1592 vm_object_t backing_object = object->backing_object; 1593 1594 if (backing_object->ref_count != 1) 1595 return; 1596 1597 backing_object->ref_count += 2; 1598 1599 vm_object_backing_scan(object, OBSC_COLLAPSE_NOWAIT); 1600 1601 backing_object->ref_count -= 2; 1602 } 1603 1604 /* 1605 * Collapse an object with the object backing it. Pages in the backing 1606 * object are moved into the parent, and the backing object is deallocated. 1607 * 1608 * The caller must hold (object). 1609 */ 1610 void 1611 vm_object_collapse(vm_object_t object) 1612 { 1613 ASSERT_LWKT_TOKEN_HELD(&vm_token); 1614 ASSERT_LWKT_TOKEN_HELD(&vmobj_token); 1615 vm_object_assert_held(object); 1616 1617 while (TRUE) { 1618 vm_object_t backing_object; 1619 1620 /* 1621 * Verify that the conditions are right for collapse: 1622 * 1623 * The object exists and the backing object exists. 1624 */ 1625 if (object == NULL) 1626 break; 1627 1628 if ((backing_object = object->backing_object) == NULL) 1629 break; 1630 1631 vm_object_hold(backing_object); 1632 if (backing_object != object->backing_object) { 1633 vm_object_drop(backing_object); 1634 continue; 1635 } 1636 1637 /* 1638 * we check the backing object first, because it is most likely 1639 * not collapsable. 1640 */ 1641 if (backing_object->handle != NULL || 1642 (backing_object->type != OBJT_DEFAULT && 1643 backing_object->type != OBJT_SWAP) || 1644 (backing_object->flags & OBJ_DEAD) || 1645 object->handle != NULL || 1646 (object->type != OBJT_DEFAULT && 1647 object->type != OBJT_SWAP) || 1648 (object->flags & OBJ_DEAD)) { 1649 vm_object_drop(backing_object); 1650 break; 1651 } 1652 1653 if ( 1654 object->paging_in_progress != 0 || 1655 backing_object->paging_in_progress != 0 1656 ) { 1657 vm_object_drop(backing_object); 1658 vm_object_qcollapse(object); 1659 break; 1660 } 1661 1662 /* 1663 * We know that we can either collapse the backing object (if 1664 * the parent is the only reference to it) or (perhaps) have 1665 * the parent bypass the object if the parent happens to shadow 1666 * all the resident pages in the entire backing object. 1667 * 1668 * This is ignoring pager-backed pages such as swap pages. 1669 * vm_object_backing_scan fails the shadowing test in this 1670 * case. 1671 */ 1672 1673 if (backing_object->ref_count == 1) { 1674 /* 1675 * If there is exactly one reference to the backing 1676 * object, we can collapse it into the parent. 1677 */ 1678 vm_object_backing_scan(object, OBSC_COLLAPSE_WAIT); 1679 1680 /* 1681 * Move the pager from backing_object to object. 1682 */ 1683 1684 if (backing_object->type == OBJT_SWAP) { 1685 vm_object_pip_add(backing_object, 1); 1686 1687 /* 1688 * scrap the paging_offset junk and do a 1689 * discrete copy. This also removes major 1690 * assumptions about how the swap-pager 1691 * works from where it doesn't belong. The 1692 * new swapper is able to optimize the 1693 * destroy-source case. 1694 */ 1695 1696 vm_object_pip_add(object, 1); 1697 swap_pager_copy( 1698 backing_object, 1699 object, 1700 OFF_TO_IDX(object->backing_object_offset), TRUE); 1701 vm_object_pip_wakeup(object); 1702 1703 vm_object_pip_wakeup(backing_object); 1704 } 1705 /* 1706 * Object now shadows whatever backing_object did. 1707 * Note that the reference to 1708 * backing_object->backing_object moves from within 1709 * backing_object to within object. 1710 */ 1711 1712 LIST_REMOVE(object, shadow_list); 1713 object->backing_object->shadow_count--; 1714 object->backing_object->generation++; 1715 if (backing_object->backing_object) { 1716 LIST_REMOVE(backing_object, shadow_list); 1717 backing_object->backing_object->shadow_count--; 1718 backing_object->backing_object->generation++; 1719 } 1720 object->backing_object = backing_object->backing_object; 1721 if (object->backing_object) { 1722 LIST_INSERT_HEAD( 1723 &object->backing_object->shadow_head, 1724 object, 1725 shadow_list 1726 ); 1727 object->backing_object->shadow_count++; 1728 object->backing_object->generation++; 1729 } 1730 1731 object->backing_object_offset += 1732 backing_object->backing_object_offset; 1733 1734 /* 1735 * Discard backing_object. 1736 * 1737 * Since the backing object has no pages, no pager left, 1738 * and no object references within it, all that is 1739 * necessary is to dispose of it. 1740 */ 1741 1742 KASSERT(backing_object->ref_count == 1, 1743 ("backing_object %p was somehow " 1744 "re-referenced during collapse!", 1745 backing_object)); 1746 KASSERT(RB_EMPTY(&backing_object->rb_memq), 1747 ("backing_object %p somehow has left " 1748 "over pages during collapse!", 1749 backing_object)); 1750 1751 /* 1752 * Wait for hold count to hit zero 1753 */ 1754 vm_object_drop(backing_object); 1755 vm_object_hold_wait(backing_object); 1756 1757 /* (we are holding vmobj_token) */ 1758 TAILQ_REMOVE(&vm_object_list, backing_object, 1759 object_list); 1760 --backing_object->ref_count; /* safety/debug */ 1761 vm_object_count--; 1762 1763 zfree(obj_zone, backing_object); 1764 1765 object_collapses++; 1766 } else { 1767 vm_object_t new_backing_object; 1768 1769 /* 1770 * If we do not entirely shadow the backing object, 1771 * there is nothing we can do so we give up. 1772 */ 1773 1774 if (vm_object_backing_scan(object, OBSC_TEST_ALL_SHADOWED) == 0) { 1775 vm_object_drop(backing_object); 1776 break; 1777 } 1778 1779 /* 1780 * Make the parent shadow the next object in the 1781 * chain. Deallocating backing_object will not remove 1782 * it, since its reference count is at least 2. 1783 */ 1784 1785 LIST_REMOVE(object, shadow_list); 1786 backing_object->shadow_count--; 1787 backing_object->generation++; 1788 1789 new_backing_object = backing_object->backing_object; 1790 if ((object->backing_object = new_backing_object) != NULL) { 1791 vm_object_reference(new_backing_object); 1792 LIST_INSERT_HEAD( 1793 &new_backing_object->shadow_head, 1794 object, 1795 shadow_list 1796 ); 1797 new_backing_object->shadow_count++; 1798 new_backing_object->generation++; 1799 object->backing_object_offset += 1800 backing_object->backing_object_offset; 1801 } 1802 1803 /* 1804 * Drop the reference count on backing_object. Since 1805 * its ref_count was at least 2, it will not vanish; 1806 * so we don't need to call vm_object_deallocate, but 1807 * we do anyway. 1808 */ 1809 vm_object_drop(backing_object); 1810 vm_object_deallocate_locked(backing_object); 1811 object_bypasses++; 1812 } 1813 1814 /* 1815 * Try again with this object's new backing object. 1816 */ 1817 } 1818 } 1819 1820 /* 1821 * Removes all physical pages in the specified object range from the 1822 * object's list of pages. 1823 * 1824 * No requirements. 1825 */ 1826 static int vm_object_page_remove_callback(vm_page_t p, void *data); 1827 1828 void 1829 vm_object_page_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end, 1830 boolean_t clean_only) 1831 { 1832 struct rb_vm_page_scan_info info; 1833 int all; 1834 1835 /* 1836 * Degenerate cases and assertions 1837 */ 1838 lwkt_gettoken(&vm_token); 1839 if (object == NULL || 1840 (object->resident_page_count == 0 && object->swblock_count == 0)) { 1841 lwkt_reltoken(&vm_token); 1842 return; 1843 } 1844 KASSERT(object->type != OBJT_PHYS, 1845 ("attempt to remove pages from a physical object")); 1846 1847 /* 1848 * Indicate that paging is occuring on the object 1849 */ 1850 crit_enter(); 1851 vm_object_pip_add(object, 1); 1852 1853 /* 1854 * Figure out the actual removal range and whether we are removing 1855 * the entire contents of the object or not. If removing the entire 1856 * contents, be sure to get all pages, even those that might be 1857 * beyond the end of the object. 1858 */ 1859 info.start_pindex = start; 1860 if (end == 0) 1861 info.end_pindex = (vm_pindex_t)-1; 1862 else 1863 info.end_pindex = end - 1; 1864 info.limit = clean_only; 1865 all = (start == 0 && info.end_pindex >= object->size - 1); 1866 1867 /* 1868 * Loop until we are sure we have gotten them all. 1869 */ 1870 do { 1871 info.error = 0; 1872 vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp, 1873 vm_object_page_remove_callback, &info); 1874 } while (info.error); 1875 1876 /* 1877 * Remove any related swap if throwing away pages, or for 1878 * non-swap objects (the swap is a clean copy in that case). 1879 */ 1880 if (object->type != OBJT_SWAP || clean_only == FALSE) { 1881 if (all) 1882 swap_pager_freespace_all(object); 1883 else 1884 swap_pager_freespace(object, info.start_pindex, 1885 info.end_pindex - info.start_pindex + 1); 1886 } 1887 1888 /* 1889 * Cleanup 1890 */ 1891 vm_object_pip_wakeup(object); 1892 crit_exit(); 1893 lwkt_reltoken(&vm_token); 1894 } 1895 1896 /* 1897 * The caller must hold vm_token. 1898 */ 1899 static int 1900 vm_object_page_remove_callback(vm_page_t p, void *data) 1901 { 1902 struct rb_vm_page_scan_info *info = data; 1903 1904 /* 1905 * Wired pages cannot be destroyed, but they can be invalidated 1906 * and we do so if clean_only (limit) is not set. 1907 * 1908 * WARNING! The page may be wired due to being part of a buffer 1909 * cache buffer, and the buffer might be marked B_CACHE. 1910 * This is fine as part of a truncation but VFSs must be 1911 * sure to fix the buffer up when re-extending the file. 1912 */ 1913 if (p->wire_count != 0) { 1914 vm_page_protect(p, VM_PROT_NONE); 1915 if (info->limit == 0) 1916 p->valid = 0; 1917 return(0); 1918 } 1919 1920 /* 1921 * The busy flags are only cleared at 1922 * interrupt -- minimize the spl transitions 1923 */ 1924 1925 if (vm_page_sleep_busy(p, TRUE, "vmopar")) { 1926 info->error = 1; 1927 return(0); 1928 } 1929 1930 /* 1931 * limit is our clean_only flag. If set and the page is dirty, do 1932 * not free it. If set and the page is being held by someone, do 1933 * not free it. 1934 */ 1935 if (info->limit && p->valid) { 1936 vm_page_test_dirty(p); 1937 if (p->valid & p->dirty) 1938 return(0); 1939 if (p->hold_count) 1940 return(0); 1941 } 1942 1943 /* 1944 * Destroy the page 1945 */ 1946 vm_page_busy(p); 1947 vm_page_protect(p, VM_PROT_NONE); 1948 vm_page_free(p); 1949 return(0); 1950 } 1951 1952 /* 1953 * Coalesces two objects backing up adjoining regions of memory into a 1954 * single object. 1955 * 1956 * returns TRUE if objects were combined. 1957 * 1958 * NOTE: Only works at the moment if the second object is NULL - 1959 * if it's not, which object do we lock first? 1960 * 1961 * Parameters: 1962 * prev_object First object to coalesce 1963 * prev_offset Offset into prev_object 1964 * next_object Second object into coalesce 1965 * next_offset Offset into next_object 1966 * 1967 * prev_size Size of reference to prev_object 1968 * next_size Size of reference to next_object 1969 * 1970 * The caller must hold vm_token and vmobj_token. 1971 * 1972 * The caller does not need to hold (prev_object) but must have a stable 1973 * pointer to it (typically by holding the vm_map locked). 1974 */ 1975 boolean_t 1976 vm_object_coalesce(vm_object_t prev_object, vm_pindex_t prev_pindex, 1977 vm_size_t prev_size, vm_size_t next_size) 1978 { 1979 vm_pindex_t next_pindex; 1980 1981 ASSERT_LWKT_TOKEN_HELD(&vm_token); 1982 ASSERT_LWKT_TOKEN_HELD(&vmobj_token); 1983 1984 if (prev_object == NULL) { 1985 return (TRUE); 1986 } 1987 1988 vm_object_hold(prev_object); 1989 1990 if (prev_object->type != OBJT_DEFAULT && 1991 prev_object->type != OBJT_SWAP) { 1992 vm_object_drop(prev_object); 1993 return (FALSE); 1994 } 1995 1996 /* 1997 * Try to collapse the object first 1998 */ 1999 vm_object_collapse(prev_object); 2000 2001 /* 2002 * Can't coalesce if: . more than one reference . paged out . shadows 2003 * another object . has a copy elsewhere (any of which mean that the 2004 * pages not mapped to prev_entry may be in use anyway) 2005 */ 2006 2007 if (prev_object->backing_object != NULL) { 2008 vm_object_drop(prev_object); 2009 return (FALSE); 2010 } 2011 2012 prev_size >>= PAGE_SHIFT; 2013 next_size >>= PAGE_SHIFT; 2014 next_pindex = prev_pindex + prev_size; 2015 2016 if ((prev_object->ref_count > 1) && 2017 (prev_object->size != next_pindex)) { 2018 vm_object_drop(prev_object); 2019 return (FALSE); 2020 } 2021 2022 /* 2023 * Remove any pages that may still be in the object from a previous 2024 * deallocation. 2025 */ 2026 if (next_pindex < prev_object->size) { 2027 vm_object_page_remove(prev_object, 2028 next_pindex, 2029 next_pindex + next_size, FALSE); 2030 if (prev_object->type == OBJT_SWAP) 2031 swap_pager_freespace(prev_object, 2032 next_pindex, next_size); 2033 } 2034 2035 /* 2036 * Extend the object if necessary. 2037 */ 2038 if (next_pindex + next_size > prev_object->size) 2039 prev_object->size = next_pindex + next_size; 2040 2041 vm_object_drop(prev_object); 2042 return (TRUE); 2043 } 2044 2045 /* 2046 * Make the object writable and flag is being possibly dirty. 2047 * 2048 * No requirements. 2049 */ 2050 void 2051 vm_object_set_writeable_dirty(vm_object_t object) 2052 { 2053 struct vnode *vp; 2054 2055 lwkt_gettoken(&vm_token); 2056 vm_object_set_flag(object, OBJ_WRITEABLE|OBJ_MIGHTBEDIRTY); 2057 if (object->type == OBJT_VNODE && 2058 (vp = (struct vnode *)object->handle) != NULL) { 2059 if ((vp->v_flag & VOBJDIRTY) == 0) { 2060 vsetflags(vp, VOBJDIRTY); 2061 } 2062 } 2063 lwkt_reltoken(&vm_token); 2064 } 2065 2066 #include "opt_ddb.h" 2067 #ifdef DDB 2068 #include <sys/kernel.h> 2069 2070 #include <sys/cons.h> 2071 2072 #include <ddb/ddb.h> 2073 2074 static int _vm_object_in_map (vm_map_t map, vm_object_t object, 2075 vm_map_entry_t entry); 2076 static int vm_object_in_map (vm_object_t object); 2077 2078 /* 2079 * The caller must hold vm_token. 2080 */ 2081 static int 2082 _vm_object_in_map(vm_map_t map, vm_object_t object, vm_map_entry_t entry) 2083 { 2084 vm_map_t tmpm; 2085 vm_map_entry_t tmpe; 2086 vm_object_t obj; 2087 int entcount; 2088 2089 if (map == 0) 2090 return 0; 2091 if (entry == 0) { 2092 tmpe = map->header.next; 2093 entcount = map->nentries; 2094 while (entcount-- && (tmpe != &map->header)) { 2095 if( _vm_object_in_map(map, object, tmpe)) { 2096 return 1; 2097 } 2098 tmpe = tmpe->next; 2099 } 2100 return (0); 2101 } 2102 switch(entry->maptype) { 2103 case VM_MAPTYPE_SUBMAP: 2104 tmpm = entry->object.sub_map; 2105 tmpe = tmpm->header.next; 2106 entcount = tmpm->nentries; 2107 while (entcount-- && tmpe != &tmpm->header) { 2108 if( _vm_object_in_map(tmpm, object, tmpe)) { 2109 return 1; 2110 } 2111 tmpe = tmpe->next; 2112 } 2113 break; 2114 case VM_MAPTYPE_NORMAL: 2115 case VM_MAPTYPE_VPAGETABLE: 2116 obj = entry->object.vm_object; 2117 while (obj) { 2118 if (obj == object) 2119 return 1; 2120 obj = obj->backing_object; 2121 } 2122 break; 2123 default: 2124 break; 2125 } 2126 return 0; 2127 } 2128 2129 static int vm_object_in_map_callback(struct proc *p, void *data); 2130 2131 struct vm_object_in_map_info { 2132 vm_object_t object; 2133 int rv; 2134 }; 2135 2136 /* 2137 * Debugging only 2138 */ 2139 static int 2140 vm_object_in_map(vm_object_t object) 2141 { 2142 struct vm_object_in_map_info info; 2143 2144 info.rv = 0; 2145 info.object = object; 2146 2147 allproc_scan(vm_object_in_map_callback, &info); 2148 if (info.rv) 2149 return 1; 2150 if( _vm_object_in_map(&kernel_map, object, 0)) 2151 return 1; 2152 if( _vm_object_in_map(&pager_map, object, 0)) 2153 return 1; 2154 if( _vm_object_in_map(&buffer_map, object, 0)) 2155 return 1; 2156 return 0; 2157 } 2158 2159 /* 2160 * Debugging only 2161 */ 2162 static int 2163 vm_object_in_map_callback(struct proc *p, void *data) 2164 { 2165 struct vm_object_in_map_info *info = data; 2166 2167 if (p->p_vmspace) { 2168 if (_vm_object_in_map(&p->p_vmspace->vm_map, info->object, 0)) { 2169 info->rv = 1; 2170 return -1; 2171 } 2172 } 2173 return (0); 2174 } 2175 2176 DB_SHOW_COMMAND(vmochk, vm_object_check) 2177 { 2178 vm_object_t object; 2179 2180 /* 2181 * make sure that internal objs are in a map somewhere 2182 * and none have zero ref counts. 2183 */ 2184 for (object = TAILQ_FIRST(&vm_object_list); 2185 object != NULL; 2186 object = TAILQ_NEXT(object, object_list)) { 2187 if (object->type == OBJT_MARKER) 2188 continue; 2189 if (object->handle == NULL && 2190 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) { 2191 if (object->ref_count == 0) { 2192 db_printf("vmochk: internal obj has zero ref count: %ld\n", 2193 (long)object->size); 2194 } 2195 if (!vm_object_in_map(object)) { 2196 db_printf( 2197 "vmochk: internal obj is not in a map: " 2198 "ref: %d, size: %lu: 0x%lx, backing_object: %p\n", 2199 object->ref_count, (u_long)object->size, 2200 (u_long)object->size, 2201 (void *)object->backing_object); 2202 } 2203 } 2204 } 2205 } 2206 2207 /* 2208 * Debugging only 2209 */ 2210 DB_SHOW_COMMAND(object, vm_object_print_static) 2211 { 2212 /* XXX convert args. */ 2213 vm_object_t object = (vm_object_t)addr; 2214 boolean_t full = have_addr; 2215 2216 vm_page_t p; 2217 2218 /* XXX count is an (unused) arg. Avoid shadowing it. */ 2219 #define count was_count 2220 2221 int count; 2222 2223 if (object == NULL) 2224 return; 2225 2226 db_iprintf( 2227 "Object %p: type=%d, size=0x%lx, res=%d, ref=%d, flags=0x%x\n", 2228 object, (int)object->type, (u_long)object->size, 2229 object->resident_page_count, object->ref_count, object->flags); 2230 /* 2231 * XXX no %qd in kernel. Truncate object->backing_object_offset. 2232 */ 2233 db_iprintf(" sref=%d, backing_object(%d)=(%p)+0x%lx\n", 2234 object->shadow_count, 2235 object->backing_object ? object->backing_object->ref_count : 0, 2236 object->backing_object, (long)object->backing_object_offset); 2237 2238 if (!full) 2239 return; 2240 2241 db_indent += 2; 2242 count = 0; 2243 RB_FOREACH(p, vm_page_rb_tree, &object->rb_memq) { 2244 if (count == 0) 2245 db_iprintf("memory:="); 2246 else if (count == 6) { 2247 db_printf("\n"); 2248 db_iprintf(" ..."); 2249 count = 0; 2250 } else 2251 db_printf(","); 2252 count++; 2253 2254 db_printf("(off=0x%lx,page=0x%lx)", 2255 (u_long) p->pindex, (u_long) VM_PAGE_TO_PHYS(p)); 2256 } 2257 if (count != 0) 2258 db_printf("\n"); 2259 db_indent -= 2; 2260 } 2261 2262 /* XXX. */ 2263 #undef count 2264 2265 /* 2266 * XXX need this non-static entry for calling from vm_map_print. 2267 * 2268 * Debugging only 2269 */ 2270 void 2271 vm_object_print(/* db_expr_t */ long addr, 2272 boolean_t have_addr, 2273 /* db_expr_t */ long count, 2274 char *modif) 2275 { 2276 vm_object_print_static(addr, have_addr, count, modif); 2277 } 2278 2279 /* 2280 * Debugging only 2281 */ 2282 DB_SHOW_COMMAND(vmopag, vm_object_print_pages) 2283 { 2284 vm_object_t object; 2285 int nl = 0; 2286 int c; 2287 for (object = TAILQ_FIRST(&vm_object_list); 2288 object != NULL; 2289 object = TAILQ_NEXT(object, object_list)) { 2290 vm_pindex_t idx, fidx; 2291 vm_pindex_t osize; 2292 vm_paddr_t pa = -1, padiff; 2293 int rcount; 2294 vm_page_t m; 2295 2296 if (object->type == OBJT_MARKER) 2297 continue; 2298 db_printf("new object: %p\n", (void *)object); 2299 if ( nl > 18) { 2300 c = cngetc(); 2301 if (c != ' ') 2302 return; 2303 nl = 0; 2304 } 2305 nl++; 2306 rcount = 0; 2307 fidx = 0; 2308 osize = object->size; 2309 if (osize > 128) 2310 osize = 128; 2311 for (idx = 0; idx < osize; idx++) { 2312 m = vm_page_lookup(object, idx); 2313 if (m == NULL) { 2314 if (rcount) { 2315 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2316 (long)fidx, rcount, (long)pa); 2317 if ( nl > 18) { 2318 c = cngetc(); 2319 if (c != ' ') 2320 return; 2321 nl = 0; 2322 } 2323 nl++; 2324 rcount = 0; 2325 } 2326 continue; 2327 } 2328 2329 2330 if (rcount && 2331 (VM_PAGE_TO_PHYS(m) == pa + rcount * PAGE_SIZE)) { 2332 ++rcount; 2333 continue; 2334 } 2335 if (rcount) { 2336 padiff = pa + rcount * PAGE_SIZE - VM_PAGE_TO_PHYS(m); 2337 padiff >>= PAGE_SHIFT; 2338 padiff &= PQ_L2_MASK; 2339 if (padiff == 0) { 2340 pa = VM_PAGE_TO_PHYS(m) - rcount * PAGE_SIZE; 2341 ++rcount; 2342 continue; 2343 } 2344 db_printf(" index(%ld)run(%d)pa(0x%lx)", 2345 (long)fidx, rcount, (long)pa); 2346 db_printf("pd(%ld)\n", (long)padiff); 2347 if ( nl > 18) { 2348 c = cngetc(); 2349 if (c != ' ') 2350 return; 2351 nl = 0; 2352 } 2353 nl++; 2354 } 2355 fidx = idx; 2356 pa = VM_PAGE_TO_PHYS(m); 2357 rcount = 1; 2358 } 2359 if (rcount) { 2360 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2361 (long)fidx, rcount, (long)pa); 2362 if ( nl > 18) { 2363 c = cngetc(); 2364 if (c != ' ') 2365 return; 2366 nl = 0; 2367 } 2368 nl++; 2369 } 2370 } 2371 } 2372 #endif /* DDB */ 2373