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 vm_object_set_flag(object, OBJ_CLEANING); 839 840 /* 841 * Handle 'entire object' case 842 */ 843 info.start_pindex = start; 844 if (end == 0) { 845 info.end_pindex = object->size - 1; 846 } else { 847 info.end_pindex = end - 1; 848 } 849 wholescan = (start == 0 && info.end_pindex == object->size - 1); 850 info.limit = flags; 851 info.pagerflags = pagerflags; 852 info.object = object; 853 854 /* 855 * If cleaning the entire object do a pass to mark the pages read-only. 856 * If everything worked out ok, clear OBJ_WRITEABLE and 857 * OBJ_MIGHTBEDIRTY. 858 */ 859 if (wholescan) { 860 info.error = 0; 861 lwkt_gettoken(&vm_token); 862 vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp, 863 vm_object_page_clean_pass1, &info); 864 lwkt_reltoken(&vm_token); 865 if (info.error == 0) { 866 vm_object_clear_flag(object, 867 OBJ_WRITEABLE|OBJ_MIGHTBEDIRTY); 868 if (object->type == OBJT_VNODE && 869 (vp = (struct vnode *)object->handle) != NULL) { 870 if (vp->v_flag & VOBJDIRTY) 871 vclrflags(vp, VOBJDIRTY); 872 } 873 } 874 } 875 876 /* 877 * Do a pass to clean all the dirty pages we find. 878 */ 879 do { 880 info.error = 0; 881 curgeneration = object->generation; 882 lwkt_gettoken(&vm_token); 883 vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp, 884 vm_object_page_clean_pass2, &info); 885 lwkt_reltoken(&vm_token); 886 } while (info.error || curgeneration != object->generation); 887 888 vm_object_clear_flag(object, OBJ_CLEANING); 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 lwkt_gettoken(&vm_token); 1110 for (idx = start; idx < end; idx++) { 1111 p = vm_page_lookup(object, idx); 1112 if (p == NULL) 1113 continue; 1114 vm_page_protect(p, VM_PROT_READ); 1115 } 1116 lwkt_reltoken(&vm_token); 1117 } 1118 1119 /* 1120 * Removes all physical pages in the specified object range from all 1121 * physical maps. 1122 * 1123 * The object must *not* be locked. 1124 */ 1125 1126 static int vm_object_pmap_remove_callback(vm_page_t p, void *data); 1127 1128 void 1129 vm_object_pmap_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end) 1130 { 1131 struct rb_vm_page_scan_info info; 1132 1133 if (object == NULL) 1134 return; 1135 info.start_pindex = start; 1136 info.end_pindex = end - 1; 1137 1138 lwkt_gettoken(&vm_token); 1139 vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp, 1140 vm_object_pmap_remove_callback, &info); 1141 if (start == 0 && end == object->size) 1142 vm_object_clear_flag(object, OBJ_WRITEABLE); 1143 lwkt_reltoken(&vm_token); 1144 } 1145 1146 /* 1147 * The caller must hold vm_token. 1148 */ 1149 static int 1150 vm_object_pmap_remove_callback(vm_page_t p, void *data __unused) 1151 { 1152 vm_page_protect(p, VM_PROT_NONE); 1153 return(0); 1154 } 1155 1156 /* 1157 * Implements the madvise function at the object/page level. 1158 * 1159 * MADV_WILLNEED (any object) 1160 * 1161 * Activate the specified pages if they are resident. 1162 * 1163 * MADV_DONTNEED (any object) 1164 * 1165 * Deactivate the specified pages if they are resident. 1166 * 1167 * MADV_FREE (OBJT_DEFAULT/OBJT_SWAP objects, OBJ_ONEMAPPING only) 1168 * 1169 * Deactivate and clean the specified pages if they are 1170 * resident. This permits the process to reuse the pages 1171 * without faulting or the kernel to reclaim the pages 1172 * without I/O. 1173 * 1174 * No requirements. 1175 */ 1176 void 1177 vm_object_madvise(vm_object_t object, vm_pindex_t pindex, int count, int advise) 1178 { 1179 vm_pindex_t end, tpindex; 1180 vm_object_t tobject; 1181 vm_page_t m; 1182 1183 if (object == NULL) 1184 return; 1185 1186 end = pindex + count; 1187 1188 lwkt_gettoken(&vm_token); 1189 1190 /* 1191 * Locate and adjust resident pages 1192 */ 1193 for (; pindex < end; pindex += 1) { 1194 relookup: 1195 tobject = object; 1196 tpindex = pindex; 1197 shadowlookup: 1198 /* 1199 * MADV_FREE only operates on OBJT_DEFAULT or OBJT_SWAP pages 1200 * and those pages must be OBJ_ONEMAPPING. 1201 */ 1202 if (advise == MADV_FREE) { 1203 if ((tobject->type != OBJT_DEFAULT && 1204 tobject->type != OBJT_SWAP) || 1205 (tobject->flags & OBJ_ONEMAPPING) == 0) { 1206 continue; 1207 } 1208 } 1209 1210 /* 1211 * spl protection is required to avoid a race between the 1212 * lookup, an interrupt unbusy/free, and our busy check. 1213 */ 1214 1215 m = vm_page_lookup(tobject, tpindex); 1216 1217 if (m == NULL) { 1218 /* 1219 * There may be swap even if there is no backing page 1220 */ 1221 if (advise == MADV_FREE && tobject->type == OBJT_SWAP) 1222 swap_pager_freespace(tobject, tpindex, 1); 1223 1224 /* 1225 * next object 1226 */ 1227 if (tobject->backing_object == NULL) 1228 continue; 1229 tpindex += OFF_TO_IDX(tobject->backing_object_offset); 1230 tobject = tobject->backing_object; 1231 goto shadowlookup; 1232 } 1233 1234 /* 1235 * If the page is busy or not in a normal active state, 1236 * we skip it. If the page is not managed there are no 1237 * page queues to mess with. Things can break if we mess 1238 * with pages in any of the below states. 1239 */ 1240 if ( 1241 m->hold_count || 1242 m->wire_count || 1243 (m->flags & PG_UNMANAGED) || 1244 m->valid != VM_PAGE_BITS_ALL 1245 ) { 1246 continue; 1247 } 1248 1249 if (vm_page_sleep_busy(m, TRUE, "madvpo")) { 1250 goto relookup; 1251 } 1252 vm_page_busy(m); 1253 1254 /* 1255 * Theoretically once a page is known not to be busy, an 1256 * interrupt cannot come along and rip it out from under us. 1257 */ 1258 1259 if (advise == MADV_WILLNEED) { 1260 vm_page_activate(m); 1261 } else if (advise == MADV_DONTNEED) { 1262 vm_page_dontneed(m); 1263 } else if (advise == MADV_FREE) { 1264 /* 1265 * Mark the page clean. This will allow the page 1266 * to be freed up by the system. However, such pages 1267 * are often reused quickly by malloc()/free() 1268 * so we do not do anything that would cause 1269 * a page fault if we can help it. 1270 * 1271 * Specifically, we do not try to actually free 1272 * the page now nor do we try to put it in the 1273 * cache (which would cause a page fault on reuse). 1274 * 1275 * But we do make the page is freeable as we 1276 * can without actually taking the step of unmapping 1277 * it. 1278 */ 1279 pmap_clear_modify(m); 1280 m->dirty = 0; 1281 m->act_count = 0; 1282 vm_page_dontneed(m); 1283 if (tobject->type == OBJT_SWAP) 1284 swap_pager_freespace(tobject, tpindex, 1); 1285 } 1286 vm_page_wakeup(m); 1287 } 1288 lwkt_reltoken(&vm_token); 1289 } 1290 1291 /* 1292 * Create a new object which is backed by the specified existing object 1293 * range. The source object reference is deallocated. 1294 * 1295 * The new object and offset into that object are returned in the source 1296 * parameters. 1297 * 1298 * No other requirements. 1299 */ 1300 void 1301 vm_object_shadow(vm_object_t *object, vm_ooffset_t *offset, vm_size_t length) 1302 { 1303 vm_object_t source; 1304 vm_object_t result; 1305 1306 source = *object; 1307 1308 /* 1309 * Don't create the new object if the old object isn't shared. 1310 */ 1311 lwkt_gettoken(&vm_token); 1312 1313 if (source != NULL && 1314 source->ref_count == 1 && 1315 source->handle == NULL && 1316 (source->type == OBJT_DEFAULT || 1317 source->type == OBJT_SWAP)) { 1318 lwkt_reltoken(&vm_token); 1319 return; 1320 } 1321 1322 /* 1323 * Allocate a new object with the given length 1324 */ 1325 1326 if ((result = vm_object_allocate(OBJT_DEFAULT, length)) == NULL) 1327 panic("vm_object_shadow: no object for shadowing"); 1328 1329 /* 1330 * The new object shadows the source object, adding a reference to it. 1331 * Our caller changes his reference to point to the new object, 1332 * removing a reference to the source object. Net result: no change 1333 * of reference count. 1334 * 1335 * Try to optimize the result object's page color when shadowing 1336 * in order to maintain page coloring consistency in the combined 1337 * shadowed object. 1338 */ 1339 result->backing_object = source; 1340 if (source) { 1341 LIST_INSERT_HEAD(&source->shadow_head, result, shadow_list); 1342 source->shadow_count++; 1343 source->generation++; 1344 result->pg_color = (source->pg_color + OFF_TO_IDX(*offset)) & PQ_L2_MASK; 1345 } 1346 1347 /* 1348 * Store the offset into the source object, and fix up the offset into 1349 * the new object. 1350 */ 1351 result->backing_object_offset = *offset; 1352 lwkt_reltoken(&vm_token); 1353 1354 /* 1355 * Return the new things 1356 */ 1357 *offset = 0; 1358 *object = result; 1359 } 1360 1361 #define OBSC_TEST_ALL_SHADOWED 0x0001 1362 #define OBSC_COLLAPSE_NOWAIT 0x0002 1363 #define OBSC_COLLAPSE_WAIT 0x0004 1364 1365 static int vm_object_backing_scan_callback(vm_page_t p, void *data); 1366 1367 /* 1368 * The caller must hold vm_token. 1369 */ 1370 static __inline int 1371 vm_object_backing_scan(vm_object_t object, int op) 1372 { 1373 struct rb_vm_page_scan_info info; 1374 vm_object_t backing_object; 1375 1376 backing_object = object->backing_object; 1377 info.backing_offset_index = OFF_TO_IDX(object->backing_object_offset); 1378 1379 /* 1380 * Initial conditions 1381 */ 1382 1383 if (op & OBSC_TEST_ALL_SHADOWED) { 1384 /* 1385 * We do not want to have to test for the existence of 1386 * swap pages in the backing object. XXX but with the 1387 * new swapper this would be pretty easy to do. 1388 * 1389 * XXX what about anonymous MAP_SHARED memory that hasn't 1390 * been ZFOD faulted yet? If we do not test for this, the 1391 * shadow test may succeed! XXX 1392 */ 1393 if (backing_object->type != OBJT_DEFAULT) { 1394 return(0); 1395 } 1396 } 1397 if (op & OBSC_COLLAPSE_WAIT) { 1398 KKASSERT((backing_object->flags & OBJ_DEAD) == 0); 1399 vm_object_set_flag(backing_object, OBJ_DEAD); 1400 } 1401 1402 /* 1403 * Our scan. We have to retry if a negative error code is returned, 1404 * otherwise 0 or 1 will be returned in info.error. 0 Indicates that 1405 * the scan had to be stopped because the parent does not completely 1406 * shadow the child. 1407 */ 1408 info.object = object; 1409 info.backing_object = backing_object; 1410 info.limit = op; 1411 do { 1412 info.error = 1; 1413 vm_page_rb_tree_RB_SCAN(&backing_object->rb_memq, NULL, 1414 vm_object_backing_scan_callback, 1415 &info); 1416 } while (info.error < 0); 1417 1418 return(info.error); 1419 } 1420 1421 /* 1422 * The caller must hold vm_token. 1423 */ 1424 static int 1425 vm_object_backing_scan_callback(vm_page_t p, void *data) 1426 { 1427 struct rb_vm_page_scan_info *info = data; 1428 vm_object_t backing_object; 1429 vm_object_t object; 1430 vm_pindex_t new_pindex; 1431 vm_pindex_t backing_offset_index; 1432 int op; 1433 1434 new_pindex = p->pindex - info->backing_offset_index; 1435 op = info->limit; 1436 object = info->object; 1437 backing_object = info->backing_object; 1438 backing_offset_index = info->backing_offset_index; 1439 1440 if (op & OBSC_TEST_ALL_SHADOWED) { 1441 vm_page_t pp; 1442 1443 /* 1444 * Ignore pages outside the parent object's range 1445 * and outside the parent object's mapping of the 1446 * backing object. 1447 * 1448 * note that we do not busy the backing object's 1449 * page. 1450 */ 1451 if ( 1452 p->pindex < backing_offset_index || 1453 new_pindex >= object->size 1454 ) { 1455 return(0); 1456 } 1457 1458 /* 1459 * See if the parent has the page or if the parent's 1460 * object pager has the page. If the parent has the 1461 * page but the page is not valid, the parent's 1462 * object pager must have the page. 1463 * 1464 * If this fails, the parent does not completely shadow 1465 * the object and we might as well give up now. 1466 */ 1467 1468 pp = vm_page_lookup(object, new_pindex); 1469 if ((pp == NULL || pp->valid == 0) && 1470 !vm_pager_has_page(object, new_pindex) 1471 ) { 1472 info->error = 0; /* problemo */ 1473 return(-1); /* stop the scan */ 1474 } 1475 } 1476 1477 /* 1478 * Check for busy page 1479 */ 1480 1481 if (op & (OBSC_COLLAPSE_WAIT | OBSC_COLLAPSE_NOWAIT)) { 1482 vm_page_t pp; 1483 1484 if (op & OBSC_COLLAPSE_NOWAIT) { 1485 if ( 1486 (p->flags & PG_BUSY) || 1487 !p->valid || 1488 p->hold_count || 1489 p->wire_count || 1490 p->busy 1491 ) { 1492 return(0); 1493 } 1494 } else if (op & OBSC_COLLAPSE_WAIT) { 1495 if (vm_page_sleep_busy(p, TRUE, "vmocol")) { 1496 /* 1497 * If we slept, anything could have 1498 * happened. Ask that the scan be restarted. 1499 * 1500 * Since the object is marked dead, the 1501 * backing offset should not have changed. 1502 */ 1503 info->error = -1; 1504 return(-1); 1505 } 1506 } 1507 1508 /* 1509 * Busy the page 1510 */ 1511 vm_page_busy(p); 1512 1513 KASSERT( 1514 p->object == backing_object, 1515 ("vm_object_qcollapse(): object mismatch") 1516 ); 1517 1518 /* 1519 * Destroy any associated swap 1520 */ 1521 if (backing_object->type == OBJT_SWAP) 1522 swap_pager_freespace(backing_object, p->pindex, 1); 1523 1524 if ( 1525 p->pindex < backing_offset_index || 1526 new_pindex >= object->size 1527 ) { 1528 /* 1529 * Page is out of the parent object's range, we 1530 * can simply destroy it. 1531 */ 1532 vm_page_protect(p, VM_PROT_NONE); 1533 vm_page_free(p); 1534 return(0); 1535 } 1536 1537 pp = vm_page_lookup(object, new_pindex); 1538 if (pp != NULL || vm_pager_has_page(object, new_pindex)) { 1539 /* 1540 * page already exists in parent OR swap exists 1541 * for this location in the parent. Destroy 1542 * the original page from the backing object. 1543 * 1544 * Leave the parent's page alone 1545 */ 1546 vm_page_protect(p, VM_PROT_NONE); 1547 vm_page_free(p); 1548 return(0); 1549 } 1550 1551 /* 1552 * Page does not exist in parent, rename the 1553 * page from the backing object to the main object. 1554 * 1555 * If the page was mapped to a process, it can remain 1556 * mapped through the rename. 1557 */ 1558 if ((p->queue - p->pc) == PQ_CACHE) 1559 vm_page_deactivate(p); 1560 1561 vm_page_rename(p, object, new_pindex); 1562 /* page automatically made dirty by rename */ 1563 } 1564 return(0); 1565 } 1566 1567 /* 1568 * This version of collapse allows the operation to occur earlier and 1569 * when paging_in_progress is true for an object... This is not a complete 1570 * operation, but should plug 99.9% of the rest of the leaks. 1571 * 1572 * The caller must hold vm_token and vmobj_token. 1573 * (only called from vm_object_collapse) 1574 */ 1575 static void 1576 vm_object_qcollapse(vm_object_t object) 1577 { 1578 vm_object_t backing_object = object->backing_object; 1579 1580 if (backing_object->ref_count != 1) 1581 return; 1582 1583 backing_object->ref_count += 2; 1584 1585 vm_object_backing_scan(object, OBSC_COLLAPSE_NOWAIT); 1586 1587 backing_object->ref_count -= 2; 1588 } 1589 1590 /* 1591 * Collapse an object with the object backing it. Pages in the backing 1592 * object are moved into the parent, and the backing object is deallocated. 1593 * 1594 * The caller must hold (object). 1595 */ 1596 void 1597 vm_object_collapse(vm_object_t object) 1598 { 1599 ASSERT_LWKT_TOKEN_HELD(&vm_token); 1600 ASSERT_LWKT_TOKEN_HELD(&vmobj_token); 1601 vm_object_assert_held(object); 1602 1603 while (TRUE) { 1604 vm_object_t backing_object; 1605 1606 /* 1607 * Verify that the conditions are right for collapse: 1608 * 1609 * The object exists and the backing object exists. 1610 */ 1611 if (object == NULL) 1612 break; 1613 1614 if ((backing_object = object->backing_object) == NULL) 1615 break; 1616 1617 vm_object_hold(backing_object); 1618 if (backing_object != object->backing_object) { 1619 vm_object_drop(backing_object); 1620 continue; 1621 } 1622 1623 /* 1624 * we check the backing object first, because it is most likely 1625 * not collapsable. 1626 */ 1627 if (backing_object->handle != NULL || 1628 (backing_object->type != OBJT_DEFAULT && 1629 backing_object->type != OBJT_SWAP) || 1630 (backing_object->flags & OBJ_DEAD) || 1631 object->handle != NULL || 1632 (object->type != OBJT_DEFAULT && 1633 object->type != OBJT_SWAP) || 1634 (object->flags & OBJ_DEAD)) { 1635 vm_object_drop(backing_object); 1636 break; 1637 } 1638 1639 if ( 1640 object->paging_in_progress != 0 || 1641 backing_object->paging_in_progress != 0 1642 ) { 1643 vm_object_drop(backing_object); 1644 vm_object_qcollapse(object); 1645 break; 1646 } 1647 1648 /* 1649 * We know that we can either collapse the backing object (if 1650 * the parent is the only reference to it) or (perhaps) have 1651 * the parent bypass the object if the parent happens to shadow 1652 * all the resident pages in the entire backing object. 1653 * 1654 * This is ignoring pager-backed pages such as swap pages. 1655 * vm_object_backing_scan fails the shadowing test in this 1656 * case. 1657 */ 1658 1659 if (backing_object->ref_count == 1) { 1660 /* 1661 * If there is exactly one reference to the backing 1662 * object, we can collapse it into the parent. 1663 */ 1664 vm_object_backing_scan(object, OBSC_COLLAPSE_WAIT); 1665 1666 /* 1667 * Move the pager from backing_object to object. 1668 */ 1669 if (backing_object->type == OBJT_SWAP) { 1670 vm_object_pip_add(backing_object, 1); 1671 1672 /* 1673 * scrap the paging_offset junk and do a 1674 * discrete copy. This also removes major 1675 * assumptions about how the swap-pager 1676 * works from where it doesn't belong. The 1677 * new swapper is able to optimize the 1678 * destroy-source case. 1679 */ 1680 1681 vm_object_pip_add(object, 1); 1682 swap_pager_copy( 1683 backing_object, 1684 object, 1685 OFF_TO_IDX(object->backing_object_offset), TRUE); 1686 vm_object_pip_wakeup(object); 1687 1688 vm_object_pip_wakeup(backing_object); 1689 } 1690 /* 1691 * Object now shadows whatever backing_object did. 1692 * Note that the reference to 1693 * backing_object->backing_object moves from within 1694 * backing_object to within object. 1695 */ 1696 1697 LIST_REMOVE(object, shadow_list); 1698 object->backing_object->shadow_count--; 1699 object->backing_object->generation++; 1700 if (backing_object->backing_object) { 1701 LIST_REMOVE(backing_object, shadow_list); 1702 backing_object->backing_object->shadow_count--; 1703 backing_object->backing_object->generation++; 1704 } 1705 object->backing_object = backing_object->backing_object; 1706 if (object->backing_object) { 1707 LIST_INSERT_HEAD( 1708 &object->backing_object->shadow_head, 1709 object, 1710 shadow_list 1711 ); 1712 object->backing_object->shadow_count++; 1713 object->backing_object->generation++; 1714 } 1715 1716 object->backing_object_offset += 1717 backing_object->backing_object_offset; 1718 1719 /* 1720 * Discard backing_object. 1721 * 1722 * Since the backing object has no pages, no pager left, 1723 * and no object references within it, all that is 1724 * necessary is to dispose of it. 1725 */ 1726 1727 KASSERT(backing_object->ref_count == 1, 1728 ("backing_object %p was somehow " 1729 "re-referenced during collapse!", 1730 backing_object)); 1731 KASSERT(RB_EMPTY(&backing_object->rb_memq), 1732 ("backing_object %p somehow has left " 1733 "over pages during collapse!", 1734 backing_object)); 1735 1736 /* 1737 * Wait for hold count to hit zero 1738 */ 1739 vm_object_drop(backing_object); 1740 vm_object_hold_wait(backing_object); 1741 1742 /* (we are holding vmobj_token) */ 1743 TAILQ_REMOVE(&vm_object_list, backing_object, 1744 object_list); 1745 --backing_object->ref_count; /* safety/debug */ 1746 vm_object_count--; 1747 1748 zfree(obj_zone, backing_object); 1749 1750 object_collapses++; 1751 } else { 1752 vm_object_t new_backing_object; 1753 1754 /* 1755 * If we do not entirely shadow the backing object, 1756 * there is nothing we can do so we give up. 1757 */ 1758 1759 if (vm_object_backing_scan(object, OBSC_TEST_ALL_SHADOWED) == 0) { 1760 vm_object_drop(backing_object); 1761 break; 1762 } 1763 1764 /* 1765 * Make the parent shadow the next object in the 1766 * chain. Deallocating backing_object will not remove 1767 * it, since its reference count is at least 2. 1768 */ 1769 1770 LIST_REMOVE(object, shadow_list); 1771 backing_object->shadow_count--; 1772 backing_object->generation++; 1773 1774 new_backing_object = backing_object->backing_object; 1775 if ((object->backing_object = new_backing_object) != NULL) { 1776 vm_object_reference(new_backing_object); 1777 LIST_INSERT_HEAD( 1778 &new_backing_object->shadow_head, 1779 object, 1780 shadow_list 1781 ); 1782 new_backing_object->shadow_count++; 1783 new_backing_object->generation++; 1784 object->backing_object_offset += 1785 backing_object->backing_object_offset; 1786 } 1787 1788 /* 1789 * Drop the reference count on backing_object. Since 1790 * its ref_count was at least 2, it will not vanish; 1791 * so we don't need to call vm_object_deallocate, but 1792 * we do anyway. 1793 */ 1794 vm_object_drop(backing_object); 1795 vm_object_deallocate_locked(backing_object); 1796 object_bypasses++; 1797 } 1798 1799 /* 1800 * Try again with this object's new backing object. 1801 */ 1802 } 1803 } 1804 1805 /* 1806 * Removes all physical pages in the specified object range from the 1807 * object's list of pages. 1808 * 1809 * No requirements. 1810 */ 1811 static int vm_object_page_remove_callback(vm_page_t p, void *data); 1812 1813 void 1814 vm_object_page_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end, 1815 boolean_t clean_only) 1816 { 1817 struct rb_vm_page_scan_info info; 1818 int all; 1819 1820 /* 1821 * Degenerate cases and assertions 1822 */ 1823 lwkt_gettoken(&vm_token); 1824 if (object == NULL || 1825 (object->resident_page_count == 0 && object->swblock_count == 0)) { 1826 lwkt_reltoken(&vm_token); 1827 return; 1828 } 1829 KASSERT(object->type != OBJT_PHYS, 1830 ("attempt to remove pages from a physical object")); 1831 1832 /* 1833 * Indicate that paging is occuring on the object 1834 */ 1835 vm_object_pip_add(object, 1); 1836 1837 /* 1838 * Figure out the actual removal range and whether we are removing 1839 * the entire contents of the object or not. If removing the entire 1840 * contents, be sure to get all pages, even those that might be 1841 * beyond the end of the object. 1842 */ 1843 info.start_pindex = start; 1844 if (end == 0) 1845 info.end_pindex = (vm_pindex_t)-1; 1846 else 1847 info.end_pindex = end - 1; 1848 info.limit = clean_only; 1849 all = (start == 0 && info.end_pindex >= object->size - 1); 1850 1851 /* 1852 * Loop until we are sure we have gotten them all. 1853 */ 1854 do { 1855 info.error = 0; 1856 vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp, 1857 vm_object_page_remove_callback, &info); 1858 } while (info.error); 1859 1860 /* 1861 * Remove any related swap if throwing away pages, or for 1862 * non-swap objects (the swap is a clean copy in that case). 1863 */ 1864 if (object->type != OBJT_SWAP || clean_only == FALSE) { 1865 if (all) 1866 swap_pager_freespace_all(object); 1867 else 1868 swap_pager_freespace(object, info.start_pindex, 1869 info.end_pindex - info.start_pindex + 1); 1870 } 1871 1872 /* 1873 * Cleanup 1874 */ 1875 vm_object_pip_wakeup(object); 1876 lwkt_reltoken(&vm_token); 1877 } 1878 1879 /* 1880 * The caller must hold vm_token. 1881 */ 1882 static int 1883 vm_object_page_remove_callback(vm_page_t p, void *data) 1884 { 1885 struct rb_vm_page_scan_info *info = data; 1886 1887 /* 1888 * Wired pages cannot be destroyed, but they can be invalidated 1889 * and we do so if clean_only (limit) is not set. 1890 * 1891 * WARNING! The page may be wired due to being part of a buffer 1892 * cache buffer, and the buffer might be marked B_CACHE. 1893 * This is fine as part of a truncation but VFSs must be 1894 * sure to fix the buffer up when re-extending the file. 1895 */ 1896 if (p->wire_count != 0) { 1897 vm_page_protect(p, VM_PROT_NONE); 1898 if (info->limit == 0) 1899 p->valid = 0; 1900 return(0); 1901 } 1902 1903 /* 1904 * The busy flags are only cleared at 1905 * interrupt -- minimize the spl transitions 1906 */ 1907 1908 if (vm_page_sleep_busy(p, TRUE, "vmopar")) { 1909 info->error = 1; 1910 return(0); 1911 } 1912 1913 /* 1914 * limit is our clean_only flag. If set and the page is dirty, do 1915 * not free it. If set and the page is being held by someone, do 1916 * not free it. 1917 */ 1918 if (info->limit && p->valid) { 1919 vm_page_test_dirty(p); 1920 if (p->valid & p->dirty) 1921 return(0); 1922 if (p->hold_count) 1923 return(0); 1924 } 1925 1926 /* 1927 * Destroy the page 1928 */ 1929 vm_page_busy(p); 1930 vm_page_protect(p, VM_PROT_NONE); 1931 vm_page_free(p); 1932 return(0); 1933 } 1934 1935 /* 1936 * Coalesces two objects backing up adjoining regions of memory into a 1937 * single object. 1938 * 1939 * returns TRUE if objects were combined. 1940 * 1941 * NOTE: Only works at the moment if the second object is NULL - 1942 * if it's not, which object do we lock first? 1943 * 1944 * Parameters: 1945 * prev_object First object to coalesce 1946 * prev_offset Offset into prev_object 1947 * next_object Second object into coalesce 1948 * next_offset Offset into next_object 1949 * 1950 * prev_size Size of reference to prev_object 1951 * next_size Size of reference to next_object 1952 * 1953 * The caller must hold vm_token and vmobj_token. 1954 * 1955 * The caller does not need to hold (prev_object) but must have a stable 1956 * pointer to it (typically by holding the vm_map locked). 1957 */ 1958 boolean_t 1959 vm_object_coalesce(vm_object_t prev_object, vm_pindex_t prev_pindex, 1960 vm_size_t prev_size, vm_size_t next_size) 1961 { 1962 vm_pindex_t next_pindex; 1963 1964 ASSERT_LWKT_TOKEN_HELD(&vm_token); 1965 ASSERT_LWKT_TOKEN_HELD(&vmobj_token); 1966 1967 if (prev_object == NULL) { 1968 return (TRUE); 1969 } 1970 1971 vm_object_hold(prev_object); 1972 1973 if (prev_object->type != OBJT_DEFAULT && 1974 prev_object->type != OBJT_SWAP) { 1975 vm_object_drop(prev_object); 1976 return (FALSE); 1977 } 1978 1979 /* 1980 * Try to collapse the object first 1981 */ 1982 vm_object_collapse(prev_object); 1983 1984 /* 1985 * Can't coalesce if: . more than one reference . paged out . shadows 1986 * another object . has a copy elsewhere (any of which mean that the 1987 * pages not mapped to prev_entry may be in use anyway) 1988 */ 1989 1990 if (prev_object->backing_object != NULL) { 1991 vm_object_drop(prev_object); 1992 return (FALSE); 1993 } 1994 1995 prev_size >>= PAGE_SHIFT; 1996 next_size >>= PAGE_SHIFT; 1997 next_pindex = prev_pindex + prev_size; 1998 1999 if ((prev_object->ref_count > 1) && 2000 (prev_object->size != next_pindex)) { 2001 vm_object_drop(prev_object); 2002 return (FALSE); 2003 } 2004 2005 /* 2006 * Remove any pages that may still be in the object from a previous 2007 * deallocation. 2008 */ 2009 if (next_pindex < prev_object->size) { 2010 vm_object_page_remove(prev_object, 2011 next_pindex, 2012 next_pindex + next_size, FALSE); 2013 if (prev_object->type == OBJT_SWAP) 2014 swap_pager_freespace(prev_object, 2015 next_pindex, next_size); 2016 } 2017 2018 /* 2019 * Extend the object if necessary. 2020 */ 2021 if (next_pindex + next_size > prev_object->size) 2022 prev_object->size = next_pindex + next_size; 2023 2024 vm_object_drop(prev_object); 2025 return (TRUE); 2026 } 2027 2028 /* 2029 * Make the object writable and flag is being possibly dirty. 2030 * 2031 * No requirements. 2032 */ 2033 void 2034 vm_object_set_writeable_dirty(vm_object_t object) 2035 { 2036 struct vnode *vp; 2037 2038 lwkt_gettoken(&vm_token); 2039 vm_object_set_flag(object, OBJ_WRITEABLE|OBJ_MIGHTBEDIRTY); 2040 if (object->type == OBJT_VNODE && 2041 (vp = (struct vnode *)object->handle) != NULL) { 2042 if ((vp->v_flag & VOBJDIRTY) == 0) { 2043 vsetflags(vp, VOBJDIRTY); 2044 } 2045 } 2046 lwkt_reltoken(&vm_token); 2047 } 2048 2049 #include "opt_ddb.h" 2050 #ifdef DDB 2051 #include <sys/kernel.h> 2052 2053 #include <sys/cons.h> 2054 2055 #include <ddb/ddb.h> 2056 2057 static int _vm_object_in_map (vm_map_t map, vm_object_t object, 2058 vm_map_entry_t entry); 2059 static int vm_object_in_map (vm_object_t object); 2060 2061 /* 2062 * The caller must hold vm_token. 2063 */ 2064 static int 2065 _vm_object_in_map(vm_map_t map, vm_object_t object, vm_map_entry_t entry) 2066 { 2067 vm_map_t tmpm; 2068 vm_map_entry_t tmpe; 2069 vm_object_t obj; 2070 int entcount; 2071 2072 if (map == 0) 2073 return 0; 2074 if (entry == 0) { 2075 tmpe = map->header.next; 2076 entcount = map->nentries; 2077 while (entcount-- && (tmpe != &map->header)) { 2078 if( _vm_object_in_map(map, object, tmpe)) { 2079 return 1; 2080 } 2081 tmpe = tmpe->next; 2082 } 2083 return (0); 2084 } 2085 switch(entry->maptype) { 2086 case VM_MAPTYPE_SUBMAP: 2087 tmpm = entry->object.sub_map; 2088 tmpe = tmpm->header.next; 2089 entcount = tmpm->nentries; 2090 while (entcount-- && tmpe != &tmpm->header) { 2091 if( _vm_object_in_map(tmpm, object, tmpe)) { 2092 return 1; 2093 } 2094 tmpe = tmpe->next; 2095 } 2096 break; 2097 case VM_MAPTYPE_NORMAL: 2098 case VM_MAPTYPE_VPAGETABLE: 2099 obj = entry->object.vm_object; 2100 while (obj) { 2101 if (obj == object) 2102 return 1; 2103 obj = obj->backing_object; 2104 } 2105 break; 2106 default: 2107 break; 2108 } 2109 return 0; 2110 } 2111 2112 static int vm_object_in_map_callback(struct proc *p, void *data); 2113 2114 struct vm_object_in_map_info { 2115 vm_object_t object; 2116 int rv; 2117 }; 2118 2119 /* 2120 * Debugging only 2121 */ 2122 static int 2123 vm_object_in_map(vm_object_t object) 2124 { 2125 struct vm_object_in_map_info info; 2126 2127 info.rv = 0; 2128 info.object = object; 2129 2130 allproc_scan(vm_object_in_map_callback, &info); 2131 if (info.rv) 2132 return 1; 2133 if( _vm_object_in_map(&kernel_map, object, 0)) 2134 return 1; 2135 if( _vm_object_in_map(&pager_map, object, 0)) 2136 return 1; 2137 if( _vm_object_in_map(&buffer_map, object, 0)) 2138 return 1; 2139 return 0; 2140 } 2141 2142 /* 2143 * Debugging only 2144 */ 2145 static int 2146 vm_object_in_map_callback(struct proc *p, void *data) 2147 { 2148 struct vm_object_in_map_info *info = data; 2149 2150 if (p->p_vmspace) { 2151 if (_vm_object_in_map(&p->p_vmspace->vm_map, info->object, 0)) { 2152 info->rv = 1; 2153 return -1; 2154 } 2155 } 2156 return (0); 2157 } 2158 2159 DB_SHOW_COMMAND(vmochk, vm_object_check) 2160 { 2161 vm_object_t object; 2162 2163 /* 2164 * make sure that internal objs are in a map somewhere 2165 * and none have zero ref counts. 2166 */ 2167 for (object = TAILQ_FIRST(&vm_object_list); 2168 object != NULL; 2169 object = TAILQ_NEXT(object, object_list)) { 2170 if (object->type == OBJT_MARKER) 2171 continue; 2172 if (object->handle == NULL && 2173 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) { 2174 if (object->ref_count == 0) { 2175 db_printf("vmochk: internal obj has zero ref count: %ld\n", 2176 (long)object->size); 2177 } 2178 if (!vm_object_in_map(object)) { 2179 db_printf( 2180 "vmochk: internal obj is not in a map: " 2181 "ref: %d, size: %lu: 0x%lx, backing_object: %p\n", 2182 object->ref_count, (u_long)object->size, 2183 (u_long)object->size, 2184 (void *)object->backing_object); 2185 } 2186 } 2187 } 2188 } 2189 2190 /* 2191 * Debugging only 2192 */ 2193 DB_SHOW_COMMAND(object, vm_object_print_static) 2194 { 2195 /* XXX convert args. */ 2196 vm_object_t object = (vm_object_t)addr; 2197 boolean_t full = have_addr; 2198 2199 vm_page_t p; 2200 2201 /* XXX count is an (unused) arg. Avoid shadowing it. */ 2202 #define count was_count 2203 2204 int count; 2205 2206 if (object == NULL) 2207 return; 2208 2209 db_iprintf( 2210 "Object %p: type=%d, size=0x%lx, res=%d, ref=%d, flags=0x%x\n", 2211 object, (int)object->type, (u_long)object->size, 2212 object->resident_page_count, object->ref_count, object->flags); 2213 /* 2214 * XXX no %qd in kernel. Truncate object->backing_object_offset. 2215 */ 2216 db_iprintf(" sref=%d, backing_object(%d)=(%p)+0x%lx\n", 2217 object->shadow_count, 2218 object->backing_object ? object->backing_object->ref_count : 0, 2219 object->backing_object, (long)object->backing_object_offset); 2220 2221 if (!full) 2222 return; 2223 2224 db_indent += 2; 2225 count = 0; 2226 RB_FOREACH(p, vm_page_rb_tree, &object->rb_memq) { 2227 if (count == 0) 2228 db_iprintf("memory:="); 2229 else if (count == 6) { 2230 db_printf("\n"); 2231 db_iprintf(" ..."); 2232 count = 0; 2233 } else 2234 db_printf(","); 2235 count++; 2236 2237 db_printf("(off=0x%lx,page=0x%lx)", 2238 (u_long) p->pindex, (u_long) VM_PAGE_TO_PHYS(p)); 2239 } 2240 if (count != 0) 2241 db_printf("\n"); 2242 db_indent -= 2; 2243 } 2244 2245 /* XXX. */ 2246 #undef count 2247 2248 /* 2249 * XXX need this non-static entry for calling from vm_map_print. 2250 * 2251 * Debugging only 2252 */ 2253 void 2254 vm_object_print(/* db_expr_t */ long addr, 2255 boolean_t have_addr, 2256 /* db_expr_t */ long count, 2257 char *modif) 2258 { 2259 vm_object_print_static(addr, have_addr, count, modif); 2260 } 2261 2262 /* 2263 * Debugging only 2264 */ 2265 DB_SHOW_COMMAND(vmopag, vm_object_print_pages) 2266 { 2267 vm_object_t object; 2268 int nl = 0; 2269 int c; 2270 for (object = TAILQ_FIRST(&vm_object_list); 2271 object != NULL; 2272 object = TAILQ_NEXT(object, object_list)) { 2273 vm_pindex_t idx, fidx; 2274 vm_pindex_t osize; 2275 vm_paddr_t pa = -1, padiff; 2276 int rcount; 2277 vm_page_t m; 2278 2279 if (object->type == OBJT_MARKER) 2280 continue; 2281 db_printf("new object: %p\n", (void *)object); 2282 if ( nl > 18) { 2283 c = cngetc(); 2284 if (c != ' ') 2285 return; 2286 nl = 0; 2287 } 2288 nl++; 2289 rcount = 0; 2290 fidx = 0; 2291 osize = object->size; 2292 if (osize > 128) 2293 osize = 128; 2294 for (idx = 0; idx < osize; idx++) { 2295 m = vm_page_lookup(object, idx); 2296 if (m == NULL) { 2297 if (rcount) { 2298 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2299 (long)fidx, rcount, (long)pa); 2300 if ( nl > 18) { 2301 c = cngetc(); 2302 if (c != ' ') 2303 return; 2304 nl = 0; 2305 } 2306 nl++; 2307 rcount = 0; 2308 } 2309 continue; 2310 } 2311 2312 2313 if (rcount && 2314 (VM_PAGE_TO_PHYS(m) == pa + rcount * PAGE_SIZE)) { 2315 ++rcount; 2316 continue; 2317 } 2318 if (rcount) { 2319 padiff = pa + rcount * PAGE_SIZE - VM_PAGE_TO_PHYS(m); 2320 padiff >>= PAGE_SHIFT; 2321 padiff &= PQ_L2_MASK; 2322 if (padiff == 0) { 2323 pa = VM_PAGE_TO_PHYS(m) - rcount * PAGE_SIZE; 2324 ++rcount; 2325 continue; 2326 } 2327 db_printf(" index(%ld)run(%d)pa(0x%lx)", 2328 (long)fidx, rcount, (long)pa); 2329 db_printf("pd(%ld)\n", (long)padiff); 2330 if ( nl > 18) { 2331 c = cngetc(); 2332 if (c != ' ') 2333 return; 2334 nl = 0; 2335 } 2336 nl++; 2337 } 2338 fidx = idx; 2339 pa = VM_PAGE_TO_PHYS(m); 2340 rcount = 1; 2341 } 2342 if (rcount) { 2343 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2344 (long)fidx, rcount, (long)pa); 2345 if ( nl > 18) { 2346 c = cngetc(); 2347 if (c != ' ') 2348 return; 2349 nl = 0; 2350 } 2351 nl++; 2352 } 2353 } 2354 } 2355 #endif /* DDB */ 2356