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 if (object->ref_count == 2 && object->shadow_count == 1) { 515 if (object->handle == NULL && 516 (object->type == OBJT_DEFAULT || 517 object->type == OBJT_SWAP)) { 518 temp = LIST_FIRST(&object->shadow_head); 519 KASSERT(temp != NULL, 520 ("vm_object_deallocate: ref_count: " 521 "%d, shadow_count: %d", 522 object->ref_count, 523 object->shadow_count)); 524 lwkt_reltoken(&vm_token); 525 vm_object_lock(temp); 526 527 if ((temp->handle == NULL) && 528 (temp->type == OBJT_DEFAULT || 529 temp->type == OBJT_SWAP)) { 530 /* 531 * Special case, must handle ref_count 532 * manually to avoid recursion. 533 */ 534 temp->ref_count++; 535 vm_object_lock_swap(); 536 537 while ( 538 temp->paging_in_progress || 539 object->paging_in_progress 540 ) { 541 vm_object_pip_wait(temp, 542 "objde1"); 543 vm_object_pip_wait(object, 544 "objde2"); 545 } 546 547 if (temp->ref_count == 1) { 548 object->ref_count--; 549 temp->ref_count--; 550 vm_object_unlock(object); 551 object = temp; 552 goto doterm; 553 } 554 555 lwkt_gettoken(&vm_token); 556 vm_object_collapse(temp); 557 lwkt_reltoken(&vm_token); 558 object->ref_count--; 559 vm_object_unlock(object); 560 object = temp; 561 continue; 562 } 563 vm_object_unlock(temp); 564 } else { 565 lwkt_reltoken(&vm_token); 566 } 567 object->ref_count--; 568 vm_object_unlock(object); 569 break; 570 } 571 572 /* 573 * Normal dereferencing path 574 */ 575 object->ref_count--; 576 if (object->ref_count != 0) { 577 lwkt_reltoken(&vm_token); 578 vm_object_unlock(object); 579 break; 580 } 581 582 /* 583 * Termination path 584 * 585 * We may have to loop to resolve races if we block getting 586 * temp's lock. If temp is non NULL we have to swap the 587 * lock order so the original object lock as at the top 588 * of the lock heap. 589 */ 590 lwkt_reltoken(&vm_token); 591 doterm: 592 while ((temp = object->backing_object) != NULL) { 593 vm_object_lock(temp); 594 if (temp == object->backing_object) 595 break; 596 vm_object_unlock(temp); 597 } 598 if (temp) { 599 LIST_REMOVE(object, shadow_list); 600 temp->shadow_count--; 601 temp->generation++; 602 object->backing_object = NULL; 603 vm_object_lock_swap(); 604 } 605 606 /* 607 * Don't double-terminate, we could be in a termination 608 * recursion due to the terminate having to sync data 609 * to disk. 610 */ 611 if ((object->flags & OBJ_DEAD) == 0) { 612 vm_object_terminate(object); 613 /* termination ate the object lock */ 614 } else { 615 vm_object_unlock(object); 616 } 617 object = temp; 618 } 619 } 620 621 /* 622 * Destroy the specified object, freeing up related resources. 623 * 624 * The object must have zero references. 625 * 626 * The caller must be holding vmobj_token and properly interlock with 627 * OBJ_DEAD (at the moment). 628 * 629 * The caller must have locked the object only, and not be holding it. 630 * This function will eat the caller's lock on the object. 631 */ 632 static int vm_object_terminate_callback(vm_page_t p, void *data); 633 634 void 635 vm_object_terminate(vm_object_t object) 636 { 637 /* 638 * Make sure no one uses us. Once we set OBJ_DEAD we should be 639 * able to safely block. 640 */ 641 KKASSERT((object->flags & OBJ_DEAD) == 0); 642 ASSERT_LWKT_TOKEN_HELD(&vmobj_token); 643 vm_object_set_flag(object, OBJ_DEAD); 644 645 /* 646 * Wait for the pageout daemon to be done with the object 647 */ 648 vm_object_pip_wait(object, "objtrm1"); 649 650 KASSERT(!object->paging_in_progress, 651 ("vm_object_terminate: pageout in progress")); 652 653 /* 654 * Clean and free the pages, as appropriate. All references to the 655 * object are gone, so we don't need to lock it. 656 */ 657 if (object->type == OBJT_VNODE) { 658 struct vnode *vp; 659 660 /* 661 * Clean pages and flush buffers. 662 */ 663 vm_object_page_clean(object, 0, 0, OBJPC_SYNC); 664 665 vp = (struct vnode *) object->handle; 666 vinvalbuf(vp, V_SAVE, 0, 0); 667 } 668 669 /* 670 * Wait for any I/O to complete, after which there had better not 671 * be any references left on the object. 672 */ 673 vm_object_pip_wait(object, "objtrm2"); 674 675 if (object->ref_count != 0) { 676 panic("vm_object_terminate: object with references, " 677 "ref_count=%d", object->ref_count); 678 } 679 680 /* 681 * Now free any remaining pages. For internal objects, this also 682 * removes them from paging queues. Don't free wired pages, just 683 * remove them from the object. 684 */ 685 lwkt_gettoken(&vm_token); 686 vm_page_rb_tree_RB_SCAN(&object->rb_memq, NULL, 687 vm_object_terminate_callback, NULL); 688 lwkt_reltoken(&vm_token); 689 690 /* 691 * Let the pager know object is dead. 692 */ 693 vm_pager_deallocate(object); 694 695 /* 696 * Wait for the object hold count to hit zero, clean out pages as 697 * we go. 698 */ 699 lwkt_gettoken(&vm_token); 700 for (;;) { 701 vm_object_hold_wait(object); 702 if (RB_ROOT(&object->rb_memq) == NULL) 703 break; 704 kprintf("vm_object_terminate: Warning, object %p " 705 "still has %d pages\n", 706 object, object->resident_page_count); 707 vm_page_rb_tree_RB_SCAN(&object->rb_memq, NULL, 708 vm_object_terminate_callback, NULL); 709 } 710 lwkt_reltoken(&vm_token); 711 712 /* 713 * There had better not be any pages left 714 */ 715 KKASSERT(object->resident_page_count == 0); 716 717 /* 718 * Remove the object from the global object list. 719 * 720 * (we are holding vmobj_token) 721 */ 722 TAILQ_REMOVE(&vm_object_list, object, object_list); 723 vm_object_count--; 724 vm_object_dead_wakeup(object); 725 vm_object_unlock(object); 726 727 if (object->ref_count != 0) { 728 panic("vm_object_terminate2: object with references, " 729 "ref_count=%d", object->ref_count); 730 } 731 732 /* 733 * Free the space for the object. 734 */ 735 zfree(obj_zone, object); 736 } 737 738 /* 739 * The caller must hold vm_token. 740 */ 741 static int 742 vm_object_terminate_callback(vm_page_t p, void *data __unused) 743 { 744 if (p->busy || (p->flags & PG_BUSY)) 745 panic("vm_object_terminate: freeing busy page %p", p); 746 if (p->wire_count == 0) { 747 vm_page_busy(p); 748 vm_page_free(p); 749 mycpu->gd_cnt.v_pfree++; 750 } else { 751 if (p->queue != PQ_NONE) 752 kprintf("vm_object_terminate: Warning: Encountered wired page %p on queue %d\n", p, p->queue); 753 vm_page_busy(p); 754 vm_page_remove(p); 755 vm_page_wakeup(p); 756 } 757 return(0); 758 } 759 760 /* 761 * The object is dead but still has an object<->pager association. Sleep 762 * and return. The caller typically retests the association in a loop. 763 * 764 * Must be called with the vmobj_token held. 765 */ 766 void 767 vm_object_dead_sleep(vm_object_t object, const char *wmesg) 768 { 769 ASSERT_LWKT_TOKEN_HELD(&vmobj_token); 770 if (object->handle) { 771 vm_object_set_flag(object, OBJ_DEADWNT); 772 tsleep(object, 0, wmesg, 0); 773 /* object may be invalid after this point */ 774 } 775 } 776 777 /* 778 * Wakeup anyone waiting for the object<->pager disassociation on 779 * a dead object. 780 * 781 * Must be called with the vmobj_token held. 782 */ 783 void 784 vm_object_dead_wakeup(vm_object_t object) 785 { 786 ASSERT_LWKT_TOKEN_HELD(&vmobj_token); 787 if (object->flags & OBJ_DEADWNT) { 788 vm_object_clear_flag(object, OBJ_DEADWNT); 789 wakeup(object); 790 } 791 } 792 793 /* 794 * Clean all dirty pages in the specified range of object. Leaves page 795 * on whatever queue it is currently on. If NOSYNC is set then do not 796 * write out pages with PG_NOSYNC set (originally comes from MAP_NOSYNC), 797 * leaving the object dirty. 798 * 799 * When stuffing pages asynchronously, allow clustering. XXX we need a 800 * synchronous clustering mode implementation. 801 * 802 * Odd semantics: if start == end, we clean everything. 803 * 804 * The object must be locked? XXX 805 */ 806 static int vm_object_page_clean_pass1(struct vm_page *p, void *data); 807 static int vm_object_page_clean_pass2(struct vm_page *p, void *data); 808 809 void 810 vm_object_page_clean(vm_object_t object, vm_pindex_t start, vm_pindex_t end, 811 int flags) 812 { 813 struct rb_vm_page_scan_info info; 814 struct vnode *vp; 815 int wholescan; 816 int pagerflags; 817 int curgeneration; 818 819 vm_object_hold(object); 820 if (object->type != OBJT_VNODE || 821 (object->flags & OBJ_MIGHTBEDIRTY) == 0) { 822 vm_object_drop(object); 823 return; 824 } 825 826 pagerflags = (flags & (OBJPC_SYNC | OBJPC_INVAL)) ? 827 VM_PAGER_PUT_SYNC : VM_PAGER_CLUSTER_OK; 828 pagerflags |= (flags & OBJPC_INVAL) ? VM_PAGER_PUT_INVAL : 0; 829 830 vp = object->handle; 831 832 /* 833 * Interlock other major object operations. This allows us to 834 * temporarily clear OBJ_WRITEABLE and OBJ_MIGHTBEDIRTY. 835 */ 836 crit_enter(); 837 vm_object_set_flag(object, OBJ_CLEANING); 838 839 /* 840 * Handle 'entire object' case 841 */ 842 info.start_pindex = start; 843 if (end == 0) { 844 info.end_pindex = object->size - 1; 845 } else { 846 info.end_pindex = end - 1; 847 } 848 wholescan = (start == 0 && info.end_pindex == object->size - 1); 849 info.limit = flags; 850 info.pagerflags = pagerflags; 851 info.object = object; 852 853 /* 854 * If cleaning the entire object do a pass to mark the pages read-only. 855 * If everything worked out ok, clear OBJ_WRITEABLE and 856 * OBJ_MIGHTBEDIRTY. 857 */ 858 if (wholescan) { 859 info.error = 0; 860 lwkt_gettoken(&vm_token); 861 vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp, 862 vm_object_page_clean_pass1, &info); 863 lwkt_reltoken(&vm_token); 864 if (info.error == 0) { 865 vm_object_clear_flag(object, 866 OBJ_WRITEABLE|OBJ_MIGHTBEDIRTY); 867 if (object->type == OBJT_VNODE && 868 (vp = (struct vnode *)object->handle) != NULL) { 869 if (vp->v_flag & VOBJDIRTY) 870 vclrflags(vp, VOBJDIRTY); 871 } 872 } 873 } 874 875 /* 876 * Do a pass to clean all the dirty pages we find. 877 */ 878 do { 879 info.error = 0; 880 curgeneration = object->generation; 881 lwkt_gettoken(&vm_token); 882 vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp, 883 vm_object_page_clean_pass2, &info); 884 lwkt_reltoken(&vm_token); 885 } while (info.error || curgeneration != object->generation); 886 887 vm_object_clear_flag(object, OBJ_CLEANING); 888 crit_exit(); 889 vm_object_drop(object); 890 } 891 892 /* 893 * The caller must hold vm_token. 894 */ 895 static 896 int 897 vm_object_page_clean_pass1(struct vm_page *p, void *data) 898 { 899 struct rb_vm_page_scan_info *info = data; 900 901 vm_page_flag_set(p, PG_CLEANCHK); 902 if ((info->limit & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC)) 903 info->error = 1; 904 else 905 vm_page_protect(p, VM_PROT_READ); /* must not block */ 906 return(0); 907 } 908 909 /* 910 * The caller must hold vm_token. 911 */ 912 static 913 int 914 vm_object_page_clean_pass2(struct vm_page *p, void *data) 915 { 916 struct rb_vm_page_scan_info *info = data; 917 int n; 918 919 /* 920 * Do not mess with pages that were inserted after we started 921 * the cleaning pass. 922 */ 923 if ((p->flags & PG_CLEANCHK) == 0) 924 return(0); 925 926 /* 927 * Before wasting time traversing the pmaps, check for trivial 928 * cases where the page cannot be dirty. 929 */ 930 if (p->valid == 0 || (p->queue - p->pc) == PQ_CACHE) { 931 KKASSERT((p->dirty & p->valid) == 0); 932 return(0); 933 } 934 935 /* 936 * Check whether the page is dirty or not. The page has been set 937 * to be read-only so the check will not race a user dirtying the 938 * page. 939 */ 940 vm_page_test_dirty(p); 941 if ((p->dirty & p->valid) == 0) { 942 vm_page_flag_clear(p, PG_CLEANCHK); 943 return(0); 944 } 945 946 /* 947 * If we have been asked to skip nosync pages and this is a 948 * nosync page, skip it. Note that the object flags were 949 * not cleared in this case (because pass1 will have returned an 950 * error), so we do not have to set them. 951 */ 952 if ((info->limit & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC)) { 953 vm_page_flag_clear(p, PG_CLEANCHK); 954 return(0); 955 } 956 957 /* 958 * Flush as many pages as we can. PG_CLEANCHK will be cleared on 959 * the pages that get successfully flushed. Set info->error if 960 * we raced an object modification. 961 */ 962 n = vm_object_page_collect_flush(info->object, p, info->pagerflags); 963 if (n == 0) 964 info->error = 1; 965 return(0); 966 } 967 968 /* 969 * Collect the specified page and nearby pages and flush them out. 970 * The number of pages flushed is returned. 971 * 972 * The caller must hold vm_token. 973 */ 974 static int 975 vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int pagerflags) 976 { 977 int runlen; 978 int maxf; 979 int chkb; 980 int maxb; 981 int i; 982 int curgeneration; 983 vm_pindex_t pi; 984 vm_page_t maf[vm_pageout_page_count]; 985 vm_page_t mab[vm_pageout_page_count]; 986 vm_page_t ma[vm_pageout_page_count]; 987 988 curgeneration = object->generation; 989 990 pi = p->pindex; 991 while (vm_page_sleep_busy(p, TRUE, "vpcwai")) { 992 if (object->generation != curgeneration) { 993 return(0); 994 } 995 } 996 KKASSERT(p->object == object && p->pindex == pi); 997 998 maxf = 0; 999 for(i = 1; i < vm_pageout_page_count; i++) { 1000 vm_page_t tp; 1001 1002 if ((tp = vm_page_lookup(object, pi + i)) != NULL) { 1003 if ((tp->flags & PG_BUSY) || 1004 ((pagerflags & VM_PAGER_IGNORE_CLEANCHK) == 0 && 1005 (tp->flags & PG_CLEANCHK) == 0) || 1006 (tp->busy != 0)) 1007 break; 1008 if((tp->queue - tp->pc) == PQ_CACHE) { 1009 vm_page_flag_clear(tp, PG_CLEANCHK); 1010 break; 1011 } 1012 vm_page_test_dirty(tp); 1013 if ((tp->dirty & tp->valid) == 0) { 1014 vm_page_flag_clear(tp, PG_CLEANCHK); 1015 break; 1016 } 1017 maf[ i - 1 ] = tp; 1018 maxf++; 1019 continue; 1020 } 1021 break; 1022 } 1023 1024 maxb = 0; 1025 chkb = vm_pageout_page_count - maxf; 1026 if (chkb) { 1027 for(i = 1; i < chkb;i++) { 1028 vm_page_t tp; 1029 1030 if ((tp = vm_page_lookup(object, pi - i)) != NULL) { 1031 if ((tp->flags & PG_BUSY) || 1032 ((pagerflags & VM_PAGER_IGNORE_CLEANCHK) == 0 && 1033 (tp->flags & PG_CLEANCHK) == 0) || 1034 (tp->busy != 0)) 1035 break; 1036 if((tp->queue - tp->pc) == PQ_CACHE) { 1037 vm_page_flag_clear(tp, PG_CLEANCHK); 1038 break; 1039 } 1040 vm_page_test_dirty(tp); 1041 if ((tp->dirty & tp->valid) == 0) { 1042 vm_page_flag_clear(tp, PG_CLEANCHK); 1043 break; 1044 } 1045 mab[ i - 1 ] = tp; 1046 maxb++; 1047 continue; 1048 } 1049 break; 1050 } 1051 } 1052 1053 for(i = 0; i < maxb; i++) { 1054 int index = (maxb - i) - 1; 1055 ma[index] = mab[i]; 1056 vm_page_flag_clear(ma[index], PG_CLEANCHK); 1057 } 1058 vm_page_flag_clear(p, PG_CLEANCHK); 1059 ma[maxb] = p; 1060 for(i = 0; i < maxf; i++) { 1061 int index = (maxb + i) + 1; 1062 ma[index] = maf[i]; 1063 vm_page_flag_clear(ma[index], PG_CLEANCHK); 1064 } 1065 runlen = maxb + maxf + 1; 1066 1067 vm_pageout_flush(ma, runlen, pagerflags); 1068 for (i = 0; i < runlen; i++) { 1069 if (ma[i]->valid & ma[i]->dirty) { 1070 vm_page_protect(ma[i], VM_PROT_READ); 1071 vm_page_flag_set(ma[i], PG_CLEANCHK); 1072 1073 /* 1074 * maxf will end up being the actual number of pages 1075 * we wrote out contiguously, non-inclusive of the 1076 * first page. We do not count look-behind pages. 1077 */ 1078 if (i >= maxb + 1 && (maxf > i - maxb - 1)) 1079 maxf = i - maxb - 1; 1080 } 1081 } 1082 return(maxf + 1); 1083 } 1084 1085 /* 1086 * Same as vm_object_pmap_copy, except range checking really 1087 * works, and is meant for small sections of an object. 1088 * 1089 * This code protects resident pages by making them read-only 1090 * and is typically called on a fork or split when a page 1091 * is converted to copy-on-write. 1092 * 1093 * NOTE: If the page is already at VM_PROT_NONE, calling 1094 * vm_page_protect will have no effect. 1095 */ 1096 void 1097 vm_object_pmap_copy_1(vm_object_t object, vm_pindex_t start, vm_pindex_t end) 1098 { 1099 vm_pindex_t idx; 1100 vm_page_t p; 1101 1102 if (object == NULL || (object->flags & OBJ_WRITEABLE) == 0) 1103 return; 1104 1105 /* 1106 * spl protection needed to prevent races between the lookup, 1107 * an interrupt unbusy/free, and our protect call. 1108 */ 1109 crit_enter(); 1110 lwkt_gettoken(&vm_token); 1111 for (idx = start; idx < end; idx++) { 1112 p = vm_page_lookup(object, idx); 1113 if (p == NULL) 1114 continue; 1115 vm_page_protect(p, VM_PROT_READ); 1116 } 1117 lwkt_reltoken(&vm_token); 1118 crit_exit(); 1119 } 1120 1121 /* 1122 * Removes all physical pages in the specified object range from all 1123 * physical maps. 1124 * 1125 * The object must *not* be locked. 1126 */ 1127 1128 static int vm_object_pmap_remove_callback(vm_page_t p, void *data); 1129 1130 void 1131 vm_object_pmap_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end) 1132 { 1133 struct rb_vm_page_scan_info info; 1134 1135 if (object == NULL) 1136 return; 1137 info.start_pindex = start; 1138 info.end_pindex = end - 1; 1139 1140 crit_enter(); 1141 lwkt_gettoken(&vm_token); 1142 vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp, 1143 vm_object_pmap_remove_callback, &info); 1144 if (start == 0 && end == object->size) 1145 vm_object_clear_flag(object, OBJ_WRITEABLE); 1146 lwkt_reltoken(&vm_token); 1147 crit_exit(); 1148 } 1149 1150 /* 1151 * The caller must hold vm_token. 1152 */ 1153 static int 1154 vm_object_pmap_remove_callback(vm_page_t p, void *data __unused) 1155 { 1156 vm_page_protect(p, VM_PROT_NONE); 1157 return(0); 1158 } 1159 1160 /* 1161 * Implements the madvise function at the object/page level. 1162 * 1163 * MADV_WILLNEED (any object) 1164 * 1165 * Activate the specified pages if they are resident. 1166 * 1167 * MADV_DONTNEED (any object) 1168 * 1169 * Deactivate the specified pages if they are resident. 1170 * 1171 * MADV_FREE (OBJT_DEFAULT/OBJT_SWAP objects, OBJ_ONEMAPPING only) 1172 * 1173 * Deactivate and clean the specified pages if they are 1174 * resident. This permits the process to reuse the pages 1175 * without faulting or the kernel to reclaim the pages 1176 * without I/O. 1177 * 1178 * No requirements. 1179 */ 1180 void 1181 vm_object_madvise(vm_object_t object, vm_pindex_t pindex, int count, int advise) 1182 { 1183 vm_pindex_t end, tpindex; 1184 vm_object_t tobject; 1185 vm_page_t m; 1186 1187 if (object == NULL) 1188 return; 1189 1190 end = pindex + count; 1191 1192 lwkt_gettoken(&vm_token); 1193 1194 /* 1195 * Locate and adjust resident pages 1196 */ 1197 for (; pindex < end; pindex += 1) { 1198 relookup: 1199 tobject = object; 1200 tpindex = pindex; 1201 shadowlookup: 1202 /* 1203 * MADV_FREE only operates on OBJT_DEFAULT or OBJT_SWAP pages 1204 * and those pages must be OBJ_ONEMAPPING. 1205 */ 1206 if (advise == MADV_FREE) { 1207 if ((tobject->type != OBJT_DEFAULT && 1208 tobject->type != OBJT_SWAP) || 1209 (tobject->flags & OBJ_ONEMAPPING) == 0) { 1210 continue; 1211 } 1212 } 1213 1214 /* 1215 * spl protection is required to avoid a race between the 1216 * lookup, an interrupt unbusy/free, and our busy check. 1217 */ 1218 1219 crit_enter(); 1220 m = vm_page_lookup(tobject, tpindex); 1221 1222 if (m == NULL) { 1223 /* 1224 * There may be swap even if there is no backing page 1225 */ 1226 if (advise == MADV_FREE && tobject->type == OBJT_SWAP) 1227 swap_pager_freespace(tobject, tpindex, 1); 1228 1229 /* 1230 * next object 1231 */ 1232 crit_exit(); 1233 if (tobject->backing_object == NULL) 1234 continue; 1235 tpindex += OFF_TO_IDX(tobject->backing_object_offset); 1236 tobject = tobject->backing_object; 1237 goto shadowlookup; 1238 } 1239 1240 /* 1241 * If the page is busy or not in a normal active state, 1242 * we skip it. If the page is not managed there are no 1243 * page queues to mess with. Things can break if we mess 1244 * with pages in any of the below states. 1245 */ 1246 if ( 1247 m->hold_count || 1248 m->wire_count || 1249 (m->flags & PG_UNMANAGED) || 1250 m->valid != VM_PAGE_BITS_ALL 1251 ) { 1252 crit_exit(); 1253 continue; 1254 } 1255 1256 if (vm_page_sleep_busy(m, TRUE, "madvpo")) { 1257 crit_exit(); 1258 goto relookup; 1259 } 1260 vm_page_busy(m); 1261 crit_exit(); 1262 1263 /* 1264 * Theoretically once a page is known not to be busy, an 1265 * interrupt cannot come along and rip it out from under us. 1266 */ 1267 1268 if (advise == MADV_WILLNEED) { 1269 vm_page_activate(m); 1270 } else if (advise == MADV_DONTNEED) { 1271 vm_page_dontneed(m); 1272 } else if (advise == MADV_FREE) { 1273 /* 1274 * Mark the page clean. This will allow the page 1275 * to be freed up by the system. However, such pages 1276 * are often reused quickly by malloc()/free() 1277 * so we do not do anything that would cause 1278 * a page fault if we can help it. 1279 * 1280 * Specifically, we do not try to actually free 1281 * the page now nor do we try to put it in the 1282 * cache (which would cause a page fault on reuse). 1283 * 1284 * But we do make the page is freeable as we 1285 * can without actually taking the step of unmapping 1286 * it. 1287 */ 1288 pmap_clear_modify(m); 1289 m->dirty = 0; 1290 m->act_count = 0; 1291 vm_page_dontneed(m); 1292 if (tobject->type == OBJT_SWAP) 1293 swap_pager_freespace(tobject, tpindex, 1); 1294 } 1295 vm_page_wakeup(m); 1296 } 1297 lwkt_reltoken(&vm_token); 1298 } 1299 1300 /* 1301 * Create a new object which is backed by the specified existing object 1302 * range. The source object reference is deallocated. 1303 * 1304 * The new object and offset into that object are returned in the source 1305 * parameters. 1306 * 1307 * No other requirements. 1308 */ 1309 void 1310 vm_object_shadow(vm_object_t *object, vm_ooffset_t *offset, vm_size_t length) 1311 { 1312 vm_object_t source; 1313 vm_object_t result; 1314 1315 source = *object; 1316 1317 /* 1318 * Don't create the new object if the old object isn't shared. 1319 */ 1320 lwkt_gettoken(&vm_token); 1321 1322 if (source != NULL && 1323 source->ref_count == 1 && 1324 source->handle == NULL && 1325 (source->type == OBJT_DEFAULT || 1326 source->type == OBJT_SWAP)) { 1327 lwkt_reltoken(&vm_token); 1328 return; 1329 } 1330 1331 /* 1332 * Allocate a new object with the given length 1333 */ 1334 1335 if ((result = vm_object_allocate(OBJT_DEFAULT, length)) == NULL) 1336 panic("vm_object_shadow: no object for shadowing"); 1337 1338 /* 1339 * The new object shadows the source object, adding a reference to it. 1340 * Our caller changes his reference to point to the new object, 1341 * removing a reference to the source object. Net result: no change 1342 * of reference count. 1343 * 1344 * Try to optimize the result object's page color when shadowing 1345 * in order to maintain page coloring consistency in the combined 1346 * shadowed object. 1347 */ 1348 result->backing_object = source; 1349 if (source) { 1350 LIST_INSERT_HEAD(&source->shadow_head, result, shadow_list); 1351 source->shadow_count++; 1352 source->generation++; 1353 result->pg_color = (source->pg_color + OFF_TO_IDX(*offset)) & PQ_L2_MASK; 1354 } 1355 1356 /* 1357 * Store the offset into the source object, and fix up the offset into 1358 * the new object. 1359 */ 1360 result->backing_object_offset = *offset; 1361 lwkt_reltoken(&vm_token); 1362 1363 /* 1364 * Return the new things 1365 */ 1366 *offset = 0; 1367 *object = result; 1368 } 1369 1370 #define OBSC_TEST_ALL_SHADOWED 0x0001 1371 #define OBSC_COLLAPSE_NOWAIT 0x0002 1372 #define OBSC_COLLAPSE_WAIT 0x0004 1373 1374 static int vm_object_backing_scan_callback(vm_page_t p, void *data); 1375 1376 /* 1377 * The caller must hold vm_token. 1378 */ 1379 static __inline int 1380 vm_object_backing_scan(vm_object_t object, int op) 1381 { 1382 struct rb_vm_page_scan_info info; 1383 vm_object_t backing_object; 1384 1385 crit_enter(); 1386 1387 backing_object = object->backing_object; 1388 info.backing_offset_index = OFF_TO_IDX(object->backing_object_offset); 1389 1390 /* 1391 * Initial conditions 1392 */ 1393 1394 if (op & OBSC_TEST_ALL_SHADOWED) { 1395 /* 1396 * We do not want to have to test for the existence of 1397 * swap pages in the backing object. XXX but with the 1398 * new swapper this would be pretty easy to do. 1399 * 1400 * XXX what about anonymous MAP_SHARED memory that hasn't 1401 * been ZFOD faulted yet? If we do not test for this, the 1402 * shadow test may succeed! XXX 1403 */ 1404 if (backing_object->type != OBJT_DEFAULT) { 1405 crit_exit(); 1406 return(0); 1407 } 1408 } 1409 if (op & OBSC_COLLAPSE_WAIT) { 1410 KKASSERT((backing_object->flags & OBJ_DEAD) == 0); 1411 vm_object_set_flag(backing_object, OBJ_DEAD); 1412 } 1413 1414 /* 1415 * Our scan. We have to retry if a negative error code is returned, 1416 * otherwise 0 or 1 will be returned in info.error. 0 Indicates that 1417 * the scan had to be stopped because the parent does not completely 1418 * shadow the child. 1419 */ 1420 info.object = object; 1421 info.backing_object = backing_object; 1422 info.limit = op; 1423 do { 1424 info.error = 1; 1425 vm_page_rb_tree_RB_SCAN(&backing_object->rb_memq, NULL, 1426 vm_object_backing_scan_callback, 1427 &info); 1428 } while (info.error < 0); 1429 crit_exit(); 1430 return(info.error); 1431 } 1432 1433 /* 1434 * The caller must hold vm_token. 1435 */ 1436 static int 1437 vm_object_backing_scan_callback(vm_page_t p, void *data) 1438 { 1439 struct rb_vm_page_scan_info *info = data; 1440 vm_object_t backing_object; 1441 vm_object_t object; 1442 vm_pindex_t new_pindex; 1443 vm_pindex_t backing_offset_index; 1444 int op; 1445 1446 new_pindex = p->pindex - info->backing_offset_index; 1447 op = info->limit; 1448 object = info->object; 1449 backing_object = info->backing_object; 1450 backing_offset_index = info->backing_offset_index; 1451 1452 if (op & OBSC_TEST_ALL_SHADOWED) { 1453 vm_page_t pp; 1454 1455 /* 1456 * Ignore pages outside the parent object's range 1457 * and outside the parent object's mapping of the 1458 * backing object. 1459 * 1460 * note that we do not busy the backing object's 1461 * page. 1462 */ 1463 if ( 1464 p->pindex < backing_offset_index || 1465 new_pindex >= object->size 1466 ) { 1467 return(0); 1468 } 1469 1470 /* 1471 * See if the parent has the page or if the parent's 1472 * object pager has the page. If the parent has the 1473 * page but the page is not valid, the parent's 1474 * object pager must have the page. 1475 * 1476 * If this fails, the parent does not completely shadow 1477 * the object and we might as well give up now. 1478 */ 1479 1480 pp = vm_page_lookup(object, new_pindex); 1481 if ((pp == NULL || pp->valid == 0) && 1482 !vm_pager_has_page(object, new_pindex) 1483 ) { 1484 info->error = 0; /* problemo */ 1485 return(-1); /* stop the scan */ 1486 } 1487 } 1488 1489 /* 1490 * Check for busy page 1491 */ 1492 1493 if (op & (OBSC_COLLAPSE_WAIT | OBSC_COLLAPSE_NOWAIT)) { 1494 vm_page_t pp; 1495 1496 if (op & OBSC_COLLAPSE_NOWAIT) { 1497 if ( 1498 (p->flags & PG_BUSY) || 1499 !p->valid || 1500 p->hold_count || 1501 p->wire_count || 1502 p->busy 1503 ) { 1504 return(0); 1505 } 1506 } else if (op & OBSC_COLLAPSE_WAIT) { 1507 if (vm_page_sleep_busy(p, TRUE, "vmocol")) { 1508 /* 1509 * If we slept, anything could have 1510 * happened. Ask that the scan be restarted. 1511 * 1512 * Since the object is marked dead, the 1513 * backing offset should not have changed. 1514 */ 1515 info->error = -1; 1516 return(-1); 1517 } 1518 } 1519 1520 /* 1521 * Busy the page 1522 */ 1523 vm_page_busy(p); 1524 1525 KASSERT( 1526 p->object == backing_object, 1527 ("vm_object_qcollapse(): object mismatch") 1528 ); 1529 1530 /* 1531 * Destroy any associated swap 1532 */ 1533 if (backing_object->type == OBJT_SWAP) 1534 swap_pager_freespace(backing_object, p->pindex, 1); 1535 1536 if ( 1537 p->pindex < backing_offset_index || 1538 new_pindex >= object->size 1539 ) { 1540 /* 1541 * Page is out of the parent object's range, we 1542 * can simply destroy it. 1543 */ 1544 vm_page_protect(p, VM_PROT_NONE); 1545 vm_page_free(p); 1546 return(0); 1547 } 1548 1549 pp = vm_page_lookup(object, new_pindex); 1550 if (pp != NULL || vm_pager_has_page(object, new_pindex)) { 1551 /* 1552 * page already exists in parent OR swap exists 1553 * for this location in the parent. Destroy 1554 * the original page from the backing object. 1555 * 1556 * Leave the parent's page alone 1557 */ 1558 vm_page_protect(p, VM_PROT_NONE); 1559 vm_page_free(p); 1560 return(0); 1561 } 1562 1563 /* 1564 * Page does not exist in parent, rename the 1565 * page from the backing object to the main object. 1566 * 1567 * If the page was mapped to a process, it can remain 1568 * mapped through the rename. 1569 */ 1570 if ((p->queue - p->pc) == PQ_CACHE) 1571 vm_page_deactivate(p); 1572 1573 vm_page_rename(p, object, new_pindex); 1574 /* page automatically made dirty by rename */ 1575 } 1576 return(0); 1577 } 1578 1579 /* 1580 * This version of collapse allows the operation to occur earlier and 1581 * when paging_in_progress is true for an object... This is not a complete 1582 * operation, but should plug 99.9% of the rest of the leaks. 1583 * 1584 * The caller must hold vm_token and vmobj_token. 1585 * (only called from vm_object_collapse) 1586 */ 1587 static void 1588 vm_object_qcollapse(vm_object_t object) 1589 { 1590 vm_object_t backing_object = object->backing_object; 1591 1592 if (backing_object->ref_count != 1) 1593 return; 1594 1595 backing_object->ref_count += 2; 1596 1597 vm_object_backing_scan(object, OBSC_COLLAPSE_NOWAIT); 1598 1599 backing_object->ref_count -= 2; 1600 } 1601 1602 /* 1603 * Collapse an object with the object backing it. Pages in the backing 1604 * object are moved into the parent, and the backing object is deallocated. 1605 * 1606 * The caller must hold (object). 1607 */ 1608 void 1609 vm_object_collapse(vm_object_t object) 1610 { 1611 ASSERT_LWKT_TOKEN_HELD(&vm_token); 1612 ASSERT_LWKT_TOKEN_HELD(&vmobj_token); 1613 vm_object_assert_held(object); 1614 1615 while (TRUE) { 1616 vm_object_t backing_object; 1617 1618 /* 1619 * Verify that the conditions are right for collapse: 1620 * 1621 * The object exists and the backing object exists. 1622 */ 1623 if (object == NULL) 1624 break; 1625 1626 if ((backing_object = object->backing_object) == NULL) 1627 break; 1628 1629 vm_object_hold(backing_object); 1630 if (backing_object != object->backing_object) { 1631 vm_object_drop(backing_object); 1632 continue; 1633 } 1634 1635 /* 1636 * we check the backing object first, because it is most likely 1637 * not collapsable. 1638 */ 1639 if (backing_object->handle != NULL || 1640 (backing_object->type != OBJT_DEFAULT && 1641 backing_object->type != OBJT_SWAP) || 1642 (backing_object->flags & OBJ_DEAD) || 1643 object->handle != NULL || 1644 (object->type != OBJT_DEFAULT && 1645 object->type != OBJT_SWAP) || 1646 (object->flags & OBJ_DEAD)) { 1647 vm_object_drop(backing_object); 1648 break; 1649 } 1650 1651 if ( 1652 object->paging_in_progress != 0 || 1653 backing_object->paging_in_progress != 0 1654 ) { 1655 vm_object_drop(backing_object); 1656 vm_object_qcollapse(object); 1657 break; 1658 } 1659 1660 /* 1661 * We know that we can either collapse the backing object (if 1662 * the parent is the only reference to it) or (perhaps) have 1663 * the parent bypass the object if the parent happens to shadow 1664 * all the resident pages in the entire backing object. 1665 * 1666 * This is ignoring pager-backed pages such as swap pages. 1667 * vm_object_backing_scan fails the shadowing test in this 1668 * case. 1669 */ 1670 1671 if (backing_object->ref_count == 1) { 1672 /* 1673 * If there is exactly one reference to the backing 1674 * object, we can collapse it into the parent. 1675 */ 1676 vm_object_backing_scan(object, OBSC_COLLAPSE_WAIT); 1677 1678 /* 1679 * Move the pager from backing_object to object. 1680 */ 1681 1682 if (backing_object->type == OBJT_SWAP) { 1683 vm_object_pip_add(backing_object, 1); 1684 1685 /* 1686 * scrap the paging_offset junk and do a 1687 * discrete copy. This also removes major 1688 * assumptions about how the swap-pager 1689 * works from where it doesn't belong. The 1690 * new swapper is able to optimize the 1691 * destroy-source case. 1692 */ 1693 1694 vm_object_pip_add(object, 1); 1695 swap_pager_copy( 1696 backing_object, 1697 object, 1698 OFF_TO_IDX(object->backing_object_offset), TRUE); 1699 vm_object_pip_wakeup(object); 1700 1701 vm_object_pip_wakeup(backing_object); 1702 } 1703 /* 1704 * Object now shadows whatever backing_object did. 1705 * Note that the reference to 1706 * backing_object->backing_object moves from within 1707 * backing_object to within object. 1708 */ 1709 1710 LIST_REMOVE(object, shadow_list); 1711 object->backing_object->shadow_count--; 1712 object->backing_object->generation++; 1713 if (backing_object->backing_object) { 1714 LIST_REMOVE(backing_object, shadow_list); 1715 backing_object->backing_object->shadow_count--; 1716 backing_object->backing_object->generation++; 1717 } 1718 object->backing_object = backing_object->backing_object; 1719 if (object->backing_object) { 1720 LIST_INSERT_HEAD( 1721 &object->backing_object->shadow_head, 1722 object, 1723 shadow_list 1724 ); 1725 object->backing_object->shadow_count++; 1726 object->backing_object->generation++; 1727 } 1728 1729 object->backing_object_offset += 1730 backing_object->backing_object_offset; 1731 1732 /* 1733 * Discard backing_object. 1734 * 1735 * Since the backing object has no pages, no pager left, 1736 * and no object references within it, all that is 1737 * necessary is to dispose of it. 1738 */ 1739 1740 KASSERT(backing_object->ref_count == 1, 1741 ("backing_object %p was somehow " 1742 "re-referenced during collapse!", 1743 backing_object)); 1744 KASSERT(RB_EMPTY(&backing_object->rb_memq), 1745 ("backing_object %p somehow has left " 1746 "over pages during collapse!", 1747 backing_object)); 1748 1749 /* 1750 * Wait for hold count to hit zero 1751 */ 1752 vm_object_drop(backing_object); 1753 vm_object_hold_wait(backing_object); 1754 1755 /* (we are holding vmobj_token) */ 1756 TAILQ_REMOVE(&vm_object_list, backing_object, 1757 object_list); 1758 vm_object_count--; 1759 1760 zfree(obj_zone, backing_object); 1761 1762 object_collapses++; 1763 } else { 1764 vm_object_t new_backing_object; 1765 1766 /* 1767 * If we do not entirely shadow the backing object, 1768 * there is nothing we can do so we give up. 1769 */ 1770 1771 if (vm_object_backing_scan(object, OBSC_TEST_ALL_SHADOWED) == 0) { 1772 vm_object_drop(backing_object); 1773 break; 1774 } 1775 1776 /* 1777 * Make the parent shadow the next object in the 1778 * chain. Deallocating backing_object will not remove 1779 * it, since its reference count is at least 2. 1780 */ 1781 1782 LIST_REMOVE(object, shadow_list); 1783 backing_object->shadow_count--; 1784 backing_object->generation++; 1785 1786 new_backing_object = backing_object->backing_object; 1787 if ((object->backing_object = new_backing_object) != NULL) { 1788 vm_object_reference(new_backing_object); 1789 LIST_INSERT_HEAD( 1790 &new_backing_object->shadow_head, 1791 object, 1792 shadow_list 1793 ); 1794 new_backing_object->shadow_count++; 1795 new_backing_object->generation++; 1796 object->backing_object_offset += 1797 backing_object->backing_object_offset; 1798 } 1799 1800 /* 1801 * Drop the reference count on backing_object. Since 1802 * its ref_count was at least 2, it will not vanish; 1803 * so we don't need to call vm_object_deallocate, but 1804 * we do anyway. 1805 */ 1806 vm_object_drop(backing_object); 1807 vm_object_deallocate_locked(backing_object); 1808 object_bypasses++; 1809 } 1810 1811 /* 1812 * Try again with this object's new backing object. 1813 */ 1814 } 1815 } 1816 1817 /* 1818 * Removes all physical pages in the specified object range from the 1819 * object's list of pages. 1820 * 1821 * No requirements. 1822 */ 1823 static int vm_object_page_remove_callback(vm_page_t p, void *data); 1824 1825 void 1826 vm_object_page_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end, 1827 boolean_t clean_only) 1828 { 1829 struct rb_vm_page_scan_info info; 1830 int all; 1831 1832 /* 1833 * Degenerate cases and assertions 1834 */ 1835 lwkt_gettoken(&vm_token); 1836 if (object == NULL || 1837 (object->resident_page_count == 0 && object->swblock_count == 0)) { 1838 lwkt_reltoken(&vm_token); 1839 return; 1840 } 1841 KASSERT(object->type != OBJT_PHYS, 1842 ("attempt to remove pages from a physical object")); 1843 1844 /* 1845 * Indicate that paging is occuring on the object 1846 */ 1847 crit_enter(); 1848 vm_object_pip_add(object, 1); 1849 1850 /* 1851 * Figure out the actual removal range and whether we are removing 1852 * the entire contents of the object or not. If removing the entire 1853 * contents, be sure to get all pages, even those that might be 1854 * beyond the end of the object. 1855 */ 1856 info.start_pindex = start; 1857 if (end == 0) 1858 info.end_pindex = (vm_pindex_t)-1; 1859 else 1860 info.end_pindex = end - 1; 1861 info.limit = clean_only; 1862 all = (start == 0 && info.end_pindex >= object->size - 1); 1863 1864 /* 1865 * Loop until we are sure we have gotten them all. 1866 */ 1867 do { 1868 info.error = 0; 1869 vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp, 1870 vm_object_page_remove_callback, &info); 1871 } while (info.error); 1872 1873 /* 1874 * Remove any related swap if throwing away pages, or for 1875 * non-swap objects (the swap is a clean copy in that case). 1876 */ 1877 if (object->type != OBJT_SWAP || clean_only == FALSE) { 1878 if (all) 1879 swap_pager_freespace_all(object); 1880 else 1881 swap_pager_freespace(object, info.start_pindex, 1882 info.end_pindex - info.start_pindex + 1); 1883 } 1884 1885 /* 1886 * Cleanup 1887 */ 1888 vm_object_pip_wakeup(object); 1889 crit_exit(); 1890 lwkt_reltoken(&vm_token); 1891 } 1892 1893 /* 1894 * The caller must hold vm_token. 1895 */ 1896 static int 1897 vm_object_page_remove_callback(vm_page_t p, void *data) 1898 { 1899 struct rb_vm_page_scan_info *info = data; 1900 1901 /* 1902 * Wired pages cannot be destroyed, but they can be invalidated 1903 * and we do so if clean_only (limit) is not set. 1904 * 1905 * WARNING! The page may be wired due to being part of a buffer 1906 * cache buffer, and the buffer might be marked B_CACHE. 1907 * This is fine as part of a truncation but VFSs must be 1908 * sure to fix the buffer up when re-extending the file. 1909 */ 1910 if (p->wire_count != 0) { 1911 vm_page_protect(p, VM_PROT_NONE); 1912 if (info->limit == 0) 1913 p->valid = 0; 1914 return(0); 1915 } 1916 1917 /* 1918 * The busy flags are only cleared at 1919 * interrupt -- minimize the spl transitions 1920 */ 1921 1922 if (vm_page_sleep_busy(p, TRUE, "vmopar")) { 1923 info->error = 1; 1924 return(0); 1925 } 1926 1927 /* 1928 * limit is our clean_only flag. If set and the page is dirty, do 1929 * not free it. If set and the page is being held by someone, do 1930 * not free it. 1931 */ 1932 if (info->limit && p->valid) { 1933 vm_page_test_dirty(p); 1934 if (p->valid & p->dirty) 1935 return(0); 1936 if (p->hold_count) 1937 return(0); 1938 } 1939 1940 /* 1941 * Destroy the page 1942 */ 1943 vm_page_busy(p); 1944 vm_page_protect(p, VM_PROT_NONE); 1945 vm_page_free(p); 1946 return(0); 1947 } 1948 1949 /* 1950 * Coalesces two objects backing up adjoining regions of memory into a 1951 * single object. 1952 * 1953 * returns TRUE if objects were combined. 1954 * 1955 * NOTE: Only works at the moment if the second object is NULL - 1956 * if it's not, which object do we lock first? 1957 * 1958 * Parameters: 1959 * prev_object First object to coalesce 1960 * prev_offset Offset into prev_object 1961 * next_object Second object into coalesce 1962 * next_offset Offset into next_object 1963 * 1964 * prev_size Size of reference to prev_object 1965 * next_size Size of reference to next_object 1966 * 1967 * The caller must hold vm_token and vmobj_token. 1968 * 1969 * The caller does not need to hold (prev_object) but must have a stable 1970 * pointer to it (typically by holding the vm_map locked). 1971 */ 1972 boolean_t 1973 vm_object_coalesce(vm_object_t prev_object, vm_pindex_t prev_pindex, 1974 vm_size_t prev_size, vm_size_t next_size) 1975 { 1976 vm_pindex_t next_pindex; 1977 1978 ASSERT_LWKT_TOKEN_HELD(&vm_token); 1979 ASSERT_LWKT_TOKEN_HELD(&vmobj_token); 1980 1981 if (prev_object == NULL) { 1982 return (TRUE); 1983 } 1984 1985 vm_object_hold(prev_object); 1986 1987 if (prev_object->type != OBJT_DEFAULT && 1988 prev_object->type != OBJT_SWAP) { 1989 vm_object_drop(prev_object); 1990 return (FALSE); 1991 } 1992 1993 /* 1994 * Try to collapse the object first 1995 */ 1996 vm_object_collapse(prev_object); 1997 1998 /* 1999 * Can't coalesce if: . more than one reference . paged out . shadows 2000 * another object . has a copy elsewhere (any of which mean that the 2001 * pages not mapped to prev_entry may be in use anyway) 2002 */ 2003 2004 if (prev_object->backing_object != NULL) { 2005 vm_object_drop(prev_object); 2006 return (FALSE); 2007 } 2008 2009 prev_size >>= PAGE_SHIFT; 2010 next_size >>= PAGE_SHIFT; 2011 next_pindex = prev_pindex + prev_size; 2012 2013 if ((prev_object->ref_count > 1) && 2014 (prev_object->size != next_pindex)) { 2015 vm_object_drop(prev_object); 2016 return (FALSE); 2017 } 2018 2019 /* 2020 * Remove any pages that may still be in the object from a previous 2021 * deallocation. 2022 */ 2023 if (next_pindex < prev_object->size) { 2024 vm_object_page_remove(prev_object, 2025 next_pindex, 2026 next_pindex + next_size, FALSE); 2027 if (prev_object->type == OBJT_SWAP) 2028 swap_pager_freespace(prev_object, 2029 next_pindex, next_size); 2030 } 2031 2032 /* 2033 * Extend the object if necessary. 2034 */ 2035 if (next_pindex + next_size > prev_object->size) 2036 prev_object->size = next_pindex + next_size; 2037 2038 vm_object_drop(prev_object); 2039 return (TRUE); 2040 } 2041 2042 /* 2043 * Make the object writable and flag is being possibly dirty. 2044 * 2045 * No requirements. 2046 */ 2047 void 2048 vm_object_set_writeable_dirty(vm_object_t object) 2049 { 2050 struct vnode *vp; 2051 2052 lwkt_gettoken(&vm_token); 2053 vm_object_set_flag(object, OBJ_WRITEABLE|OBJ_MIGHTBEDIRTY); 2054 if (object->type == OBJT_VNODE && 2055 (vp = (struct vnode *)object->handle) != NULL) { 2056 if ((vp->v_flag & VOBJDIRTY) == 0) { 2057 vsetflags(vp, VOBJDIRTY); 2058 } 2059 } 2060 lwkt_reltoken(&vm_token); 2061 } 2062 2063 #include "opt_ddb.h" 2064 #ifdef DDB 2065 #include <sys/kernel.h> 2066 2067 #include <sys/cons.h> 2068 2069 #include <ddb/ddb.h> 2070 2071 static int _vm_object_in_map (vm_map_t map, vm_object_t object, 2072 vm_map_entry_t entry); 2073 static int vm_object_in_map (vm_object_t object); 2074 2075 /* 2076 * The caller must hold vm_token. 2077 */ 2078 static int 2079 _vm_object_in_map(vm_map_t map, vm_object_t object, vm_map_entry_t entry) 2080 { 2081 vm_map_t tmpm; 2082 vm_map_entry_t tmpe; 2083 vm_object_t obj; 2084 int entcount; 2085 2086 if (map == 0) 2087 return 0; 2088 if (entry == 0) { 2089 tmpe = map->header.next; 2090 entcount = map->nentries; 2091 while (entcount-- && (tmpe != &map->header)) { 2092 if( _vm_object_in_map(map, object, tmpe)) { 2093 return 1; 2094 } 2095 tmpe = tmpe->next; 2096 } 2097 return (0); 2098 } 2099 switch(entry->maptype) { 2100 case VM_MAPTYPE_SUBMAP: 2101 tmpm = entry->object.sub_map; 2102 tmpe = tmpm->header.next; 2103 entcount = tmpm->nentries; 2104 while (entcount-- && tmpe != &tmpm->header) { 2105 if( _vm_object_in_map(tmpm, object, tmpe)) { 2106 return 1; 2107 } 2108 tmpe = tmpe->next; 2109 } 2110 break; 2111 case VM_MAPTYPE_NORMAL: 2112 case VM_MAPTYPE_VPAGETABLE: 2113 obj = entry->object.vm_object; 2114 while (obj) { 2115 if (obj == object) 2116 return 1; 2117 obj = obj->backing_object; 2118 } 2119 break; 2120 default: 2121 break; 2122 } 2123 return 0; 2124 } 2125 2126 static int vm_object_in_map_callback(struct proc *p, void *data); 2127 2128 struct vm_object_in_map_info { 2129 vm_object_t object; 2130 int rv; 2131 }; 2132 2133 /* 2134 * Debugging only 2135 */ 2136 static int 2137 vm_object_in_map(vm_object_t object) 2138 { 2139 struct vm_object_in_map_info info; 2140 2141 info.rv = 0; 2142 info.object = object; 2143 2144 allproc_scan(vm_object_in_map_callback, &info); 2145 if (info.rv) 2146 return 1; 2147 if( _vm_object_in_map(&kernel_map, object, 0)) 2148 return 1; 2149 if( _vm_object_in_map(&pager_map, object, 0)) 2150 return 1; 2151 if( _vm_object_in_map(&buffer_map, object, 0)) 2152 return 1; 2153 return 0; 2154 } 2155 2156 /* 2157 * Debugging only 2158 */ 2159 static int 2160 vm_object_in_map_callback(struct proc *p, void *data) 2161 { 2162 struct vm_object_in_map_info *info = data; 2163 2164 if (p->p_vmspace) { 2165 if (_vm_object_in_map(&p->p_vmspace->vm_map, info->object, 0)) { 2166 info->rv = 1; 2167 return -1; 2168 } 2169 } 2170 return (0); 2171 } 2172 2173 DB_SHOW_COMMAND(vmochk, vm_object_check) 2174 { 2175 vm_object_t object; 2176 2177 /* 2178 * make sure that internal objs are in a map somewhere 2179 * and none have zero ref counts. 2180 */ 2181 for (object = TAILQ_FIRST(&vm_object_list); 2182 object != NULL; 2183 object = TAILQ_NEXT(object, object_list)) { 2184 if (object->type == OBJT_MARKER) 2185 continue; 2186 if (object->handle == NULL && 2187 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) { 2188 if (object->ref_count == 0) { 2189 db_printf("vmochk: internal obj has zero ref count: %ld\n", 2190 (long)object->size); 2191 } 2192 if (!vm_object_in_map(object)) { 2193 db_printf( 2194 "vmochk: internal obj is not in a map: " 2195 "ref: %d, size: %lu: 0x%lx, backing_object: %p\n", 2196 object->ref_count, (u_long)object->size, 2197 (u_long)object->size, 2198 (void *)object->backing_object); 2199 } 2200 } 2201 } 2202 } 2203 2204 /* 2205 * Debugging only 2206 */ 2207 DB_SHOW_COMMAND(object, vm_object_print_static) 2208 { 2209 /* XXX convert args. */ 2210 vm_object_t object = (vm_object_t)addr; 2211 boolean_t full = have_addr; 2212 2213 vm_page_t p; 2214 2215 /* XXX count is an (unused) arg. Avoid shadowing it. */ 2216 #define count was_count 2217 2218 int count; 2219 2220 if (object == NULL) 2221 return; 2222 2223 db_iprintf( 2224 "Object %p: type=%d, size=0x%lx, res=%d, ref=%d, flags=0x%x\n", 2225 object, (int)object->type, (u_long)object->size, 2226 object->resident_page_count, object->ref_count, object->flags); 2227 /* 2228 * XXX no %qd in kernel. Truncate object->backing_object_offset. 2229 */ 2230 db_iprintf(" sref=%d, backing_object(%d)=(%p)+0x%lx\n", 2231 object->shadow_count, 2232 object->backing_object ? object->backing_object->ref_count : 0, 2233 object->backing_object, (long)object->backing_object_offset); 2234 2235 if (!full) 2236 return; 2237 2238 db_indent += 2; 2239 count = 0; 2240 RB_FOREACH(p, vm_page_rb_tree, &object->rb_memq) { 2241 if (count == 0) 2242 db_iprintf("memory:="); 2243 else if (count == 6) { 2244 db_printf("\n"); 2245 db_iprintf(" ..."); 2246 count = 0; 2247 } else 2248 db_printf(","); 2249 count++; 2250 2251 db_printf("(off=0x%lx,page=0x%lx)", 2252 (u_long) p->pindex, (u_long) VM_PAGE_TO_PHYS(p)); 2253 } 2254 if (count != 0) 2255 db_printf("\n"); 2256 db_indent -= 2; 2257 } 2258 2259 /* XXX. */ 2260 #undef count 2261 2262 /* 2263 * XXX need this non-static entry for calling from vm_map_print. 2264 * 2265 * Debugging only 2266 */ 2267 void 2268 vm_object_print(/* db_expr_t */ long addr, 2269 boolean_t have_addr, 2270 /* db_expr_t */ long count, 2271 char *modif) 2272 { 2273 vm_object_print_static(addr, have_addr, count, modif); 2274 } 2275 2276 /* 2277 * Debugging only 2278 */ 2279 DB_SHOW_COMMAND(vmopag, vm_object_print_pages) 2280 { 2281 vm_object_t object; 2282 int nl = 0; 2283 int c; 2284 for (object = TAILQ_FIRST(&vm_object_list); 2285 object != NULL; 2286 object = TAILQ_NEXT(object, object_list)) { 2287 vm_pindex_t idx, fidx; 2288 vm_pindex_t osize; 2289 vm_paddr_t pa = -1, padiff; 2290 int rcount; 2291 vm_page_t m; 2292 2293 if (object->type == OBJT_MARKER) 2294 continue; 2295 db_printf("new object: %p\n", (void *)object); 2296 if ( nl > 18) { 2297 c = cngetc(); 2298 if (c != ' ') 2299 return; 2300 nl = 0; 2301 } 2302 nl++; 2303 rcount = 0; 2304 fidx = 0; 2305 osize = object->size; 2306 if (osize > 128) 2307 osize = 128; 2308 for (idx = 0; idx < osize; idx++) { 2309 m = vm_page_lookup(object, idx); 2310 if (m == NULL) { 2311 if (rcount) { 2312 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2313 (long)fidx, rcount, (long)pa); 2314 if ( nl > 18) { 2315 c = cngetc(); 2316 if (c != ' ') 2317 return; 2318 nl = 0; 2319 } 2320 nl++; 2321 rcount = 0; 2322 } 2323 continue; 2324 } 2325 2326 2327 if (rcount && 2328 (VM_PAGE_TO_PHYS(m) == pa + rcount * PAGE_SIZE)) { 2329 ++rcount; 2330 continue; 2331 } 2332 if (rcount) { 2333 padiff = pa + rcount * PAGE_SIZE - VM_PAGE_TO_PHYS(m); 2334 padiff >>= PAGE_SHIFT; 2335 padiff &= PQ_L2_MASK; 2336 if (padiff == 0) { 2337 pa = VM_PAGE_TO_PHYS(m) - rcount * PAGE_SIZE; 2338 ++rcount; 2339 continue; 2340 } 2341 db_printf(" index(%ld)run(%d)pa(0x%lx)", 2342 (long)fidx, rcount, (long)pa); 2343 db_printf("pd(%ld)\n", (long)padiff); 2344 if ( nl > 18) { 2345 c = cngetc(); 2346 if (c != ' ') 2347 return; 2348 nl = 0; 2349 } 2350 nl++; 2351 } 2352 fidx = idx; 2353 pa = VM_PAGE_TO_PHYS(m); 2354 rcount = 1; 2355 } 2356 if (rcount) { 2357 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2358 (long)fidx, rcount, (long)pa); 2359 if ( nl > 18) { 2360 c = cngetc(); 2361 if (c != ' ') 2362 return; 2363 nl = 0; 2364 } 2365 nl++; 2366 } 2367 } 2368 } 2369 #endif /* DDB */ 2370