1 /*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * The Mach Operating System project at Carnegie-Mellon University. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * from: @(#)vm_object.c 8.5 (Berkeley) 3/22/94 33 * 34 * 35 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 36 * All rights reserved. 37 * 38 * Authors: Avadis Tevanian, Jr., Michael Wayne Young 39 * 40 * Permission to use, copy, modify and distribute this software and 41 * its documentation is hereby granted, provided that both the copyright 42 * notice and this permission notice appear in all copies of the 43 * software, derivative works or modified versions, and any portions 44 * thereof, and that both notices appear in supporting documentation. 45 * 46 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 47 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 48 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 49 * 50 * Carnegie Mellon requests users of this software to return to 51 * 52 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 53 * School of Computer Science 54 * Carnegie Mellon University 55 * Pittsburgh PA 15213-3890 56 * 57 * any improvements or extensions that they make and grant Carnegie the 58 * rights to redistribute these changes. 59 */ 60 61 /* 62 * Virtual memory object module. 63 */ 64 65 #include <sys/cdefs.h> 66 __FBSDID("$FreeBSD$"); 67 68 #include <sys/param.h> 69 #include <sys/systm.h> 70 #include <sys/lock.h> 71 #include <sys/mman.h> 72 #include <sys/mount.h> 73 #include <sys/kernel.h> 74 #include <sys/sysctl.h> 75 #include <sys/mutex.h> 76 #include <sys/proc.h> /* for curproc, pageproc */ 77 #include <sys/socket.h> 78 #include <sys/vnode.h> 79 #include <sys/vmmeter.h> 80 #include <sys/sx.h> 81 82 #include <vm/vm.h> 83 #include <vm/vm_param.h> 84 #include <vm/pmap.h> 85 #include <vm/vm_map.h> 86 #include <vm/vm_object.h> 87 #include <vm/vm_page.h> 88 #include <vm/vm_pageout.h> 89 #include <vm/vm_pager.h> 90 #include <vm/swap_pager.h> 91 #include <vm/vm_kern.h> 92 #include <vm/vm_extern.h> 93 #include <vm/uma.h> 94 95 #define EASY_SCAN_FACTOR 8 96 97 #define MSYNC_FLUSH_HARDSEQ 0x01 98 #define MSYNC_FLUSH_SOFTSEQ 0x02 99 100 /* 101 * msync / VM object flushing optimizations 102 */ 103 static int msync_flush_flags = MSYNC_FLUSH_HARDSEQ | MSYNC_FLUSH_SOFTSEQ; 104 SYSCTL_INT(_vm, OID_AUTO, msync_flush_flags, 105 CTLFLAG_RW, &msync_flush_flags, 0, ""); 106 107 static int old_msync; 108 SYSCTL_INT(_vm, OID_AUTO, old_msync, CTLFLAG_RW, &old_msync, 0, 109 "Use old (insecure) msync behavior"); 110 111 static void vm_object_qcollapse(vm_object_t object); 112 static int vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int curgeneration, int pagerflags); 113 static void vm_object_vndeallocate(vm_object_t object); 114 115 /* 116 * Virtual memory objects maintain the actual data 117 * associated with allocated virtual memory. A given 118 * page of memory exists within exactly one object. 119 * 120 * An object is only deallocated when all "references" 121 * are given up. Only one "reference" to a given 122 * region of an object should be writeable. 123 * 124 * Associated with each object is a list of all resident 125 * memory pages belonging to that object; this list is 126 * maintained by the "vm_page" module, and locked by the object's 127 * lock. 128 * 129 * Each object also records a "pager" routine which is 130 * used to retrieve (and store) pages to the proper backing 131 * storage. In addition, objects may be backed by other 132 * objects from which they were virtual-copied. 133 * 134 * The only items within the object structure which are 135 * modified after time of creation are: 136 * reference count locked by object's lock 137 * pager routine locked by object's lock 138 * 139 */ 140 141 struct object_q vm_object_list; 142 struct mtx vm_object_list_mtx; /* lock for object list and count */ 143 144 struct vm_object kernel_object_store; 145 struct vm_object kmem_object_store; 146 147 SYSCTL_DECL(_vm_stats); 148 SYSCTL_NODE(_vm_stats, OID_AUTO, object, CTLFLAG_RD, 0, "VM object stats"); 149 150 static long object_collapses; 151 SYSCTL_LONG(_vm_stats_object, OID_AUTO, collapses, CTLFLAG_RD, 152 &object_collapses, 0, "VM object collapses"); 153 154 static long object_bypasses; 155 SYSCTL_LONG(_vm_stats_object, OID_AUTO, bypasses, CTLFLAG_RD, 156 &object_bypasses, 0, "VM object bypasses"); 157 158 /* 159 * next_index determines the page color that is assigned to the next 160 * allocated object. Accesses to next_index are not synchronized 161 * because the effects of two or more object allocations using 162 * next_index simultaneously are inconsequential. At any given time, 163 * numerous objects have the same page color. 164 */ 165 static int next_index; 166 167 static uma_zone_t obj_zone; 168 169 static int vm_object_zinit(void *mem, int size, int flags); 170 171 #ifdef INVARIANTS 172 static void vm_object_zdtor(void *mem, int size, void *arg); 173 174 static void 175 vm_object_zdtor(void *mem, int size, void *arg) 176 { 177 vm_object_t object; 178 179 object = (vm_object_t)mem; 180 KASSERT(TAILQ_EMPTY(&object->memq), 181 ("object %p has resident pages", 182 object)); 183 KASSERT(object->paging_in_progress == 0, 184 ("object %p paging_in_progress = %d", 185 object, object->paging_in_progress)); 186 KASSERT(object->resident_page_count == 0, 187 ("object %p resident_page_count = %d", 188 object, object->resident_page_count)); 189 KASSERT(object->shadow_count == 0, 190 ("object %p shadow_count = %d", 191 object, object->shadow_count)); 192 } 193 #endif 194 195 static int 196 vm_object_zinit(void *mem, int size, int flags) 197 { 198 vm_object_t object; 199 200 object = (vm_object_t)mem; 201 bzero(&object->mtx, sizeof(object->mtx)); 202 VM_OBJECT_LOCK_INIT(object, "standard object"); 203 204 /* These are true for any object that has been freed */ 205 object->paging_in_progress = 0; 206 object->resident_page_count = 0; 207 object->shadow_count = 0; 208 return (0); 209 } 210 211 void 212 _vm_object_allocate(objtype_t type, vm_pindex_t size, vm_object_t object) 213 { 214 int incr; 215 216 TAILQ_INIT(&object->memq); 217 LIST_INIT(&object->shadow_head); 218 219 object->root = NULL; 220 object->type = type; 221 object->size = size; 222 object->generation = 1; 223 object->ref_count = 1; 224 object->flags = 0; 225 if ((object->type == OBJT_DEFAULT) || (object->type == OBJT_SWAP)) 226 object->flags = OBJ_ONEMAPPING; 227 incr = PQ_MAXLENGTH; 228 if (size <= incr) 229 incr = size; 230 object->pg_color = next_index; 231 next_index = (object->pg_color + incr) & PQ_COLORMASK; 232 object->handle = NULL; 233 object->backing_object = NULL; 234 object->backing_object_offset = (vm_ooffset_t) 0; 235 236 mtx_lock(&vm_object_list_mtx); 237 TAILQ_INSERT_TAIL(&vm_object_list, object, object_list); 238 mtx_unlock(&vm_object_list_mtx); 239 } 240 241 /* 242 * vm_object_init: 243 * 244 * Initialize the VM objects module. 245 */ 246 void 247 vm_object_init(void) 248 { 249 TAILQ_INIT(&vm_object_list); 250 mtx_init(&vm_object_list_mtx, "vm object_list", NULL, MTX_DEF); 251 252 VM_OBJECT_LOCK_INIT(&kernel_object_store, "kernel object"); 253 _vm_object_allocate(OBJT_DEFAULT, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS), 254 kernel_object); 255 256 VM_OBJECT_LOCK_INIT(&kmem_object_store, "kmem object"); 257 _vm_object_allocate(OBJT_DEFAULT, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS), 258 kmem_object); 259 260 /* 261 * The lock portion of struct vm_object must be type stable due 262 * to vm_pageout_fallback_object_lock locking a vm object 263 * without holding any references to it. 264 */ 265 obj_zone = uma_zcreate("VM OBJECT", sizeof (struct vm_object), NULL, 266 #ifdef INVARIANTS 267 vm_object_zdtor, 268 #else 269 NULL, 270 #endif 271 vm_object_zinit, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM|UMA_ZONE_NOFREE); 272 } 273 274 void 275 vm_object_clear_flag(vm_object_t object, u_short bits) 276 { 277 278 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 279 object->flags &= ~bits; 280 } 281 282 void 283 vm_object_pip_add(vm_object_t object, short i) 284 { 285 286 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 287 object->paging_in_progress += i; 288 } 289 290 void 291 vm_object_pip_subtract(vm_object_t object, short i) 292 { 293 294 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 295 object->paging_in_progress -= i; 296 } 297 298 void 299 vm_object_pip_wakeup(vm_object_t object) 300 { 301 302 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 303 object->paging_in_progress--; 304 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) { 305 vm_object_clear_flag(object, OBJ_PIPWNT); 306 wakeup(object); 307 } 308 } 309 310 void 311 vm_object_pip_wakeupn(vm_object_t object, short i) 312 { 313 314 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 315 if (i) 316 object->paging_in_progress -= i; 317 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) { 318 vm_object_clear_flag(object, OBJ_PIPWNT); 319 wakeup(object); 320 } 321 } 322 323 void 324 vm_object_pip_wait(vm_object_t object, char *waitid) 325 { 326 327 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 328 while (object->paging_in_progress) { 329 object->flags |= OBJ_PIPWNT; 330 msleep(object, VM_OBJECT_MTX(object), PVM, waitid, 0); 331 } 332 } 333 334 /* 335 * vm_object_allocate: 336 * 337 * Returns a new object with the given size. 338 */ 339 vm_object_t 340 vm_object_allocate(objtype_t type, vm_pindex_t size) 341 { 342 vm_object_t object; 343 344 object = (vm_object_t)uma_zalloc(obj_zone, M_WAITOK); 345 _vm_object_allocate(type, size, object); 346 return (object); 347 } 348 349 350 /* 351 * vm_object_reference: 352 * 353 * Gets another reference to the given object. Note: OBJ_DEAD 354 * objects can be referenced during final cleaning. 355 */ 356 void 357 vm_object_reference(vm_object_t object) 358 { 359 struct vnode *vp; 360 361 if (object == NULL) 362 return; 363 VM_OBJECT_LOCK(object); 364 object->ref_count++; 365 if (object->type == OBJT_VNODE) { 366 int vfslocked; 367 368 vp = object->handle; 369 VM_OBJECT_UNLOCK(object); 370 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 371 vget(vp, LK_RETRY, curthread); 372 VFS_UNLOCK_GIANT(vfslocked); 373 } else 374 VM_OBJECT_UNLOCK(object); 375 } 376 377 /* 378 * vm_object_reference_locked: 379 * 380 * Gets another reference to the given object. 381 * 382 * The object must be locked. 383 */ 384 void 385 vm_object_reference_locked(vm_object_t object) 386 { 387 struct vnode *vp; 388 389 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 390 KASSERT((object->flags & OBJ_DEAD) == 0, 391 ("vm_object_reference_locked: dead object referenced")); 392 object->ref_count++; 393 if (object->type == OBJT_VNODE) { 394 vp = object->handle; 395 vref(vp); 396 } 397 } 398 399 /* 400 * Handle deallocating an object of type OBJT_VNODE. 401 */ 402 static void 403 vm_object_vndeallocate(vm_object_t object) 404 { 405 struct vnode *vp = (struct vnode *) object->handle; 406 407 VFS_ASSERT_GIANT(vp->v_mount); 408 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 409 KASSERT(object->type == OBJT_VNODE, 410 ("vm_object_vndeallocate: not a vnode object")); 411 KASSERT(vp != NULL, ("vm_object_vndeallocate: missing vp")); 412 #ifdef INVARIANTS 413 if (object->ref_count == 0) { 414 vprint("vm_object_vndeallocate", vp); 415 panic("vm_object_vndeallocate: bad object reference count"); 416 } 417 #endif 418 419 object->ref_count--; 420 if (object->ref_count == 0) { 421 mp_fixme("Unlocked vflag access."); 422 vp->v_vflag &= ~VV_TEXT; 423 } 424 VM_OBJECT_UNLOCK(object); 425 /* 426 * vrele may need a vop lock 427 */ 428 vrele(vp); 429 } 430 431 /* 432 * vm_object_deallocate: 433 * 434 * Release a reference to the specified object, 435 * gained either through a vm_object_allocate 436 * or a vm_object_reference call. When all references 437 * are gone, storage associated with this object 438 * may be relinquished. 439 * 440 * No object may be locked. 441 */ 442 void 443 vm_object_deallocate(vm_object_t object) 444 { 445 vm_object_t temp; 446 447 while (object != NULL) { 448 int vfslocked; 449 450 vfslocked = 0; 451 restart: 452 VM_OBJECT_LOCK(object); 453 if (object->type == OBJT_VNODE) { 454 struct vnode *vp = (struct vnode *) object->handle; 455 456 /* 457 * Conditionally acquire Giant for a vnode-backed 458 * object. We have to be careful since the type of 459 * a vnode object can change while the object is 460 * unlocked. 461 */ 462 if (VFS_NEEDSGIANT(vp->v_mount) && !vfslocked) { 463 vfslocked = 1; 464 if (!mtx_trylock(&Giant)) { 465 VM_OBJECT_UNLOCK(object); 466 mtx_lock(&Giant); 467 goto restart; 468 } 469 } 470 vm_object_vndeallocate(object); 471 VFS_UNLOCK_GIANT(vfslocked); 472 return; 473 } else 474 /* 475 * This is to handle the case that the object 476 * changed type while we dropped its lock to 477 * obtain Giant. 478 */ 479 VFS_UNLOCK_GIANT(vfslocked); 480 481 KASSERT(object->ref_count != 0, 482 ("vm_object_deallocate: object deallocated too many times: %d", object->type)); 483 484 /* 485 * If the reference count goes to 0 we start calling 486 * vm_object_terminate() on the object chain. 487 * A ref count of 1 may be a special case depending on the 488 * shadow count being 0 or 1. 489 */ 490 object->ref_count--; 491 if (object->ref_count > 1) { 492 VM_OBJECT_UNLOCK(object); 493 return; 494 } else if (object->ref_count == 1) { 495 if (object->shadow_count == 0) { 496 vm_object_set_flag(object, OBJ_ONEMAPPING); 497 } else if ((object->shadow_count == 1) && 498 (object->handle == NULL) && 499 (object->type == OBJT_DEFAULT || 500 object->type == OBJT_SWAP)) { 501 vm_object_t robject; 502 503 robject = LIST_FIRST(&object->shadow_head); 504 KASSERT(robject != NULL, 505 ("vm_object_deallocate: ref_count: %d, shadow_count: %d", 506 object->ref_count, 507 object->shadow_count)); 508 if (!VM_OBJECT_TRYLOCK(robject)) { 509 /* 510 * Avoid a potential deadlock. 511 */ 512 object->ref_count++; 513 VM_OBJECT_UNLOCK(object); 514 /* 515 * More likely than not the thread 516 * holding robject's lock has lower 517 * priority than the current thread. 518 * Let the lower priority thread run. 519 */ 520 tsleep(&proc0, PVM, "vmo_de", 1); 521 continue; 522 } 523 /* 524 * Collapse object into its shadow unless its 525 * shadow is dead. In that case, object will 526 * be deallocated by the thread that is 527 * deallocating its shadow. 528 */ 529 if ((robject->flags & OBJ_DEAD) == 0 && 530 (robject->handle == NULL) && 531 (robject->type == OBJT_DEFAULT || 532 robject->type == OBJT_SWAP)) { 533 534 robject->ref_count++; 535 retry: 536 if (robject->paging_in_progress) { 537 VM_OBJECT_UNLOCK(object); 538 vm_object_pip_wait(robject, 539 "objde1"); 540 temp = robject->backing_object; 541 if (object == temp) { 542 VM_OBJECT_LOCK(object); 543 goto retry; 544 } 545 } else if (object->paging_in_progress) { 546 VM_OBJECT_UNLOCK(robject); 547 object->flags |= OBJ_PIPWNT; 548 msleep(object, 549 VM_OBJECT_MTX(object), 550 PDROP | PVM, "objde2", 0); 551 VM_OBJECT_LOCK(robject); 552 temp = robject->backing_object; 553 if (object == temp) { 554 VM_OBJECT_LOCK(object); 555 goto retry; 556 } 557 } else 558 VM_OBJECT_UNLOCK(object); 559 560 if (robject->ref_count == 1) { 561 robject->ref_count--; 562 object = robject; 563 goto doterm; 564 } 565 object = robject; 566 vm_object_collapse(object); 567 VM_OBJECT_UNLOCK(object); 568 continue; 569 } 570 VM_OBJECT_UNLOCK(robject); 571 } 572 VM_OBJECT_UNLOCK(object); 573 return; 574 } 575 doterm: 576 temp = object->backing_object; 577 if (temp != NULL) { 578 VM_OBJECT_LOCK(temp); 579 LIST_REMOVE(object, shadow_list); 580 temp->shadow_count--; 581 temp->generation++; 582 VM_OBJECT_UNLOCK(temp); 583 object->backing_object = NULL; 584 } 585 /* 586 * Don't double-terminate, we could be in a termination 587 * recursion due to the terminate having to sync data 588 * to disk. 589 */ 590 if ((object->flags & OBJ_DEAD) == 0) 591 vm_object_terminate(object); 592 else 593 VM_OBJECT_UNLOCK(object); 594 object = temp; 595 } 596 } 597 598 /* 599 * vm_object_terminate actually destroys the specified object, freeing 600 * up all previously used resources. 601 * 602 * The object must be locked. 603 * This routine may block. 604 */ 605 void 606 vm_object_terminate(vm_object_t object) 607 { 608 vm_page_t p; 609 610 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 611 612 /* 613 * Make sure no one uses us. 614 */ 615 vm_object_set_flag(object, OBJ_DEAD); 616 617 /* 618 * wait for the pageout daemon to be done with the object 619 */ 620 vm_object_pip_wait(object, "objtrm"); 621 622 KASSERT(!object->paging_in_progress, 623 ("vm_object_terminate: pageout in progress")); 624 625 /* 626 * Clean and free the pages, as appropriate. All references to the 627 * object are gone, so we don't need to lock it. 628 */ 629 if (object->type == OBJT_VNODE) { 630 struct vnode *vp = (struct vnode *)object->handle; 631 632 /* 633 * Clean pages and flush buffers. 634 */ 635 vm_object_page_clean(object, 0, 0, OBJPC_SYNC); 636 VM_OBJECT_UNLOCK(object); 637 638 vinvalbuf(vp, V_SAVE, NULL, 0, 0); 639 640 VM_OBJECT_LOCK(object); 641 } 642 643 KASSERT(object->ref_count == 0, 644 ("vm_object_terminate: object with references, ref_count=%d", 645 object->ref_count)); 646 647 /* 648 * Now free any remaining pages. For internal objects, this also 649 * removes them from paging queues. Don't free wired pages, just 650 * remove them from the object. 651 */ 652 vm_page_lock_queues(); 653 while ((p = TAILQ_FIRST(&object->memq)) != NULL) { 654 KASSERT(!p->busy && (p->flags & PG_BUSY) == 0, 655 ("vm_object_terminate: freeing busy page %p " 656 "p->busy = %d, p->flags %x\n", p, p->busy, p->flags)); 657 if (p->wire_count == 0) { 658 vm_page_free(p); 659 cnt.v_pfree++; 660 } else { 661 vm_page_remove(p); 662 } 663 } 664 vm_page_unlock_queues(); 665 666 /* 667 * Let the pager know object is dead. 668 */ 669 vm_pager_deallocate(object); 670 VM_OBJECT_UNLOCK(object); 671 672 /* 673 * Remove the object from the global object list. 674 */ 675 mtx_lock(&vm_object_list_mtx); 676 TAILQ_REMOVE(&vm_object_list, object, object_list); 677 mtx_unlock(&vm_object_list_mtx); 678 679 /* 680 * Free the space for the object. 681 */ 682 uma_zfree(obj_zone, object); 683 } 684 685 /* 686 * vm_object_page_clean 687 * 688 * Clean all dirty pages in the specified range of object. Leaves page 689 * on whatever queue it is currently on. If NOSYNC is set then do not 690 * write out pages with VPO_NOSYNC set (originally comes from MAP_NOSYNC), 691 * leaving the object dirty. 692 * 693 * When stuffing pages asynchronously, allow clustering. XXX we need a 694 * synchronous clustering mode implementation. 695 * 696 * Odd semantics: if start == end, we clean everything. 697 * 698 * The object must be locked. 699 */ 700 void 701 vm_object_page_clean(vm_object_t object, vm_pindex_t start, vm_pindex_t end, int flags) 702 { 703 vm_page_t p, np; 704 vm_pindex_t tstart, tend; 705 vm_pindex_t pi; 706 int clearobjflags; 707 int pagerflags; 708 int curgeneration; 709 710 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 711 if (object->type != OBJT_VNODE || 712 (object->flags & OBJ_MIGHTBEDIRTY) == 0) 713 return; 714 715 pagerflags = (flags & (OBJPC_SYNC | OBJPC_INVAL)) ? VM_PAGER_PUT_SYNC : VM_PAGER_CLUSTER_OK; 716 pagerflags |= (flags & OBJPC_INVAL) ? VM_PAGER_PUT_INVAL : 0; 717 718 vm_object_set_flag(object, OBJ_CLEANING); 719 720 tstart = start; 721 if (end == 0) { 722 tend = object->size; 723 } else { 724 tend = end; 725 } 726 727 vm_page_lock_queues(); 728 /* 729 * If the caller is smart and only msync()s a range he knows is 730 * dirty, we may be able to avoid an object scan. This results in 731 * a phenominal improvement in performance. We cannot do this 732 * as a matter of course because the object may be huge - e.g. 733 * the size might be in the gigabytes or terrabytes. 734 */ 735 if (msync_flush_flags & MSYNC_FLUSH_HARDSEQ) { 736 vm_pindex_t tscan; 737 int scanlimit; 738 int scanreset; 739 740 scanreset = object->resident_page_count / EASY_SCAN_FACTOR; 741 if (scanreset < 16) 742 scanreset = 16; 743 pagerflags |= VM_PAGER_IGNORE_CLEANCHK; 744 745 scanlimit = scanreset; 746 tscan = tstart; 747 while (tscan < tend) { 748 curgeneration = object->generation; 749 p = vm_page_lookup(object, tscan); 750 if (p == NULL || p->valid == 0 || 751 VM_PAGE_INQUEUE1(p, PQ_CACHE)) { 752 if (--scanlimit == 0) 753 break; 754 ++tscan; 755 continue; 756 } 757 vm_page_test_dirty(p); 758 if ((p->dirty & p->valid) == 0) { 759 if (--scanlimit == 0) 760 break; 761 ++tscan; 762 continue; 763 } 764 /* 765 * If we have been asked to skip nosync pages and 766 * this is a nosync page, we can't continue. 767 */ 768 if ((flags & OBJPC_NOSYNC) && (p->oflags & VPO_NOSYNC)) { 769 if (--scanlimit == 0) 770 break; 771 ++tscan; 772 continue; 773 } 774 scanlimit = scanreset; 775 776 /* 777 * This returns 0 if it was unable to busy the first 778 * page (i.e. had to sleep). 779 */ 780 tscan += vm_object_page_collect_flush(object, p, curgeneration, pagerflags); 781 } 782 783 /* 784 * If everything was dirty and we flushed it successfully, 785 * and the requested range is not the entire object, we 786 * don't have to mess with CLEANCHK or MIGHTBEDIRTY and can 787 * return immediately. 788 */ 789 if (tscan >= tend && (tstart || tend < object->size)) { 790 vm_page_unlock_queues(); 791 vm_object_clear_flag(object, OBJ_CLEANING); 792 return; 793 } 794 pagerflags &= ~VM_PAGER_IGNORE_CLEANCHK; 795 } 796 797 /* 798 * Generally set CLEANCHK interlock and make the page read-only so 799 * we can then clear the object flags. 800 * 801 * However, if this is a nosync mmap then the object is likely to 802 * stay dirty so do not mess with the page and do not clear the 803 * object flags. 804 */ 805 clearobjflags = 1; 806 TAILQ_FOREACH(p, &object->memq, listq) { 807 vm_page_flag_set(p, PG_CLEANCHK); 808 if ((flags & OBJPC_NOSYNC) && (p->oflags & VPO_NOSYNC)) 809 clearobjflags = 0; 810 else 811 pmap_remove_write(p); 812 } 813 814 if (clearobjflags && (tstart == 0) && (tend == object->size)) { 815 struct vnode *vp; 816 817 vm_object_clear_flag(object, OBJ_MIGHTBEDIRTY); 818 if (object->type == OBJT_VNODE && 819 (vp = (struct vnode *)object->handle) != NULL) { 820 VI_LOCK(vp); 821 if (vp->v_iflag & VI_OBJDIRTY) 822 vp->v_iflag &= ~VI_OBJDIRTY; 823 VI_UNLOCK(vp); 824 } 825 } 826 827 rescan: 828 curgeneration = object->generation; 829 830 for (p = TAILQ_FIRST(&object->memq); p; p = np) { 831 int n; 832 833 np = TAILQ_NEXT(p, listq); 834 835 again: 836 pi = p->pindex; 837 if (((p->flags & PG_CLEANCHK) == 0) || 838 (pi < tstart) || (pi >= tend) || 839 (p->valid == 0) || 840 VM_PAGE_INQUEUE1(p, PQ_CACHE)) { 841 vm_page_flag_clear(p, PG_CLEANCHK); 842 continue; 843 } 844 845 vm_page_test_dirty(p); 846 if ((p->dirty & p->valid) == 0) { 847 vm_page_flag_clear(p, PG_CLEANCHK); 848 continue; 849 } 850 851 /* 852 * If we have been asked to skip nosync pages and this is a 853 * nosync page, skip it. Note that the object flags were 854 * not cleared in this case so we do not have to set them. 855 */ 856 if ((flags & OBJPC_NOSYNC) && (p->oflags & VPO_NOSYNC)) { 857 vm_page_flag_clear(p, PG_CLEANCHK); 858 continue; 859 } 860 861 n = vm_object_page_collect_flush(object, p, 862 curgeneration, pagerflags); 863 if (n == 0) 864 goto rescan; 865 866 if (object->generation != curgeneration) 867 goto rescan; 868 869 /* 870 * Try to optimize the next page. If we can't we pick up 871 * our (random) scan where we left off. 872 */ 873 if (msync_flush_flags & MSYNC_FLUSH_SOFTSEQ) { 874 if ((p = vm_page_lookup(object, pi + n)) != NULL) 875 goto again; 876 } 877 } 878 vm_page_unlock_queues(); 879 #if 0 880 VOP_FSYNC(vp, (pagerflags & VM_PAGER_PUT_SYNC)?MNT_WAIT:0, curproc); 881 #endif 882 883 vm_object_clear_flag(object, OBJ_CLEANING); 884 return; 885 } 886 887 static int 888 vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int curgeneration, int pagerflags) 889 { 890 int runlen; 891 int maxf; 892 int chkb; 893 int maxb; 894 int i; 895 vm_pindex_t pi; 896 vm_page_t maf[vm_pageout_page_count]; 897 vm_page_t mab[vm_pageout_page_count]; 898 vm_page_t ma[vm_pageout_page_count]; 899 900 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 901 pi = p->pindex; 902 while (vm_page_sleep_if_busy(p, TRUE, "vpcwai")) { 903 vm_page_lock_queues(); 904 if (object->generation != curgeneration) { 905 return(0); 906 } 907 } 908 maxf = 0; 909 for(i = 1; i < vm_pageout_page_count; i++) { 910 vm_page_t tp; 911 912 if ((tp = vm_page_lookup(object, pi + i)) != NULL) { 913 if ((tp->flags & PG_BUSY) || 914 ((pagerflags & VM_PAGER_IGNORE_CLEANCHK) == 0 && 915 (tp->flags & PG_CLEANCHK) == 0) || 916 (tp->busy != 0)) 917 break; 918 if (VM_PAGE_INQUEUE1(tp, PQ_CACHE)) { 919 vm_page_flag_clear(tp, PG_CLEANCHK); 920 break; 921 } 922 vm_page_test_dirty(tp); 923 if ((tp->dirty & tp->valid) == 0) { 924 vm_page_flag_clear(tp, PG_CLEANCHK); 925 break; 926 } 927 maf[ i - 1 ] = tp; 928 maxf++; 929 continue; 930 } 931 break; 932 } 933 934 maxb = 0; 935 chkb = vm_pageout_page_count - maxf; 936 if (chkb) { 937 for(i = 1; i < chkb;i++) { 938 vm_page_t tp; 939 940 if ((tp = vm_page_lookup(object, pi - i)) != NULL) { 941 if ((tp->flags & PG_BUSY) || 942 ((pagerflags & VM_PAGER_IGNORE_CLEANCHK) == 0 && 943 (tp->flags & PG_CLEANCHK) == 0) || 944 (tp->busy != 0)) 945 break; 946 if (VM_PAGE_INQUEUE1(tp, PQ_CACHE)) { 947 vm_page_flag_clear(tp, PG_CLEANCHK); 948 break; 949 } 950 vm_page_test_dirty(tp); 951 if ((tp->dirty & tp->valid) == 0) { 952 vm_page_flag_clear(tp, PG_CLEANCHK); 953 break; 954 } 955 mab[ i - 1 ] = tp; 956 maxb++; 957 continue; 958 } 959 break; 960 } 961 } 962 963 for(i = 0; i < maxb; i++) { 964 int index = (maxb - i) - 1; 965 ma[index] = mab[i]; 966 vm_page_flag_clear(ma[index], PG_CLEANCHK); 967 } 968 vm_page_flag_clear(p, PG_CLEANCHK); 969 ma[maxb] = p; 970 for(i = 0; i < maxf; i++) { 971 int index = (maxb + i) + 1; 972 ma[index] = maf[i]; 973 vm_page_flag_clear(ma[index], PG_CLEANCHK); 974 } 975 runlen = maxb + maxf + 1; 976 977 vm_pageout_flush(ma, runlen, pagerflags); 978 for (i = 0; i < runlen; i++) { 979 if (ma[i]->valid & ma[i]->dirty) { 980 pmap_remove_write(ma[i]); 981 vm_page_flag_set(ma[i], PG_CLEANCHK); 982 983 /* 984 * maxf will end up being the actual number of pages 985 * we wrote out contiguously, non-inclusive of the 986 * first page. We do not count look-behind pages. 987 */ 988 if (i >= maxb + 1 && (maxf > i - maxb - 1)) 989 maxf = i - maxb - 1; 990 } 991 } 992 return(maxf + 1); 993 } 994 995 /* 996 * Note that there is absolutely no sense in writing out 997 * anonymous objects, so we track down the vnode object 998 * to write out. 999 * We invalidate (remove) all pages from the address space 1000 * for semantic correctness. 1001 * 1002 * Note: certain anonymous maps, such as MAP_NOSYNC maps, 1003 * may start out with a NULL object. 1004 */ 1005 void 1006 vm_object_sync(vm_object_t object, vm_ooffset_t offset, vm_size_t size, 1007 boolean_t syncio, boolean_t invalidate) 1008 { 1009 vm_object_t backing_object; 1010 struct vnode *vp; 1011 struct mount *mp; 1012 int flags; 1013 1014 if (object == NULL) 1015 return; 1016 VM_OBJECT_LOCK(object); 1017 while ((backing_object = object->backing_object) != NULL) { 1018 VM_OBJECT_LOCK(backing_object); 1019 offset += object->backing_object_offset; 1020 VM_OBJECT_UNLOCK(object); 1021 object = backing_object; 1022 if (object->size < OFF_TO_IDX(offset + size)) 1023 size = IDX_TO_OFF(object->size) - offset; 1024 } 1025 /* 1026 * Flush pages if writing is allowed, invalidate them 1027 * if invalidation requested. Pages undergoing I/O 1028 * will be ignored by vm_object_page_remove(). 1029 * 1030 * We cannot lock the vnode and then wait for paging 1031 * to complete without deadlocking against vm_fault. 1032 * Instead we simply call vm_object_page_remove() and 1033 * allow it to block internally on a page-by-page 1034 * basis when it encounters pages undergoing async 1035 * I/O. 1036 */ 1037 if (object->type == OBJT_VNODE && 1038 (object->flags & OBJ_MIGHTBEDIRTY) != 0) { 1039 int vfslocked; 1040 vp = object->handle; 1041 VM_OBJECT_UNLOCK(object); 1042 (void) vn_start_write(vp, &mp, V_WAIT); 1043 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 1044 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, curthread); 1045 flags = (syncio || invalidate) ? OBJPC_SYNC : 0; 1046 flags |= invalidate ? OBJPC_INVAL : 0; 1047 VM_OBJECT_LOCK(object); 1048 vm_object_page_clean(object, 1049 OFF_TO_IDX(offset), 1050 OFF_TO_IDX(offset + size + PAGE_MASK), 1051 flags); 1052 VM_OBJECT_UNLOCK(object); 1053 VOP_UNLOCK(vp, 0, curthread); 1054 VFS_UNLOCK_GIANT(vfslocked); 1055 vn_finished_write(mp); 1056 VM_OBJECT_LOCK(object); 1057 } 1058 if ((object->type == OBJT_VNODE || 1059 object->type == OBJT_DEVICE) && invalidate) { 1060 boolean_t purge; 1061 purge = old_msync || (object->type == OBJT_DEVICE); 1062 vm_object_page_remove(object, 1063 OFF_TO_IDX(offset), 1064 OFF_TO_IDX(offset + size + PAGE_MASK), 1065 purge ? FALSE : TRUE); 1066 } 1067 VM_OBJECT_UNLOCK(object); 1068 } 1069 1070 /* 1071 * vm_object_madvise: 1072 * 1073 * Implements the madvise function at the object/page level. 1074 * 1075 * MADV_WILLNEED (any object) 1076 * 1077 * Activate the specified pages if they are resident. 1078 * 1079 * MADV_DONTNEED (any object) 1080 * 1081 * Deactivate the specified pages if they are resident. 1082 * 1083 * MADV_FREE (OBJT_DEFAULT/OBJT_SWAP objects, 1084 * OBJ_ONEMAPPING only) 1085 * 1086 * Deactivate and clean the specified pages if they are 1087 * resident. This permits the process to reuse the pages 1088 * without faulting or the kernel to reclaim the pages 1089 * without I/O. 1090 */ 1091 void 1092 vm_object_madvise(vm_object_t object, vm_pindex_t pindex, int count, int advise) 1093 { 1094 vm_pindex_t end, tpindex; 1095 vm_object_t backing_object, tobject; 1096 vm_page_t m; 1097 1098 if (object == NULL) 1099 return; 1100 VM_OBJECT_LOCK(object); 1101 end = pindex + count; 1102 /* 1103 * Locate and adjust resident pages 1104 */ 1105 for (; pindex < end; pindex += 1) { 1106 relookup: 1107 tobject = object; 1108 tpindex = pindex; 1109 shadowlookup: 1110 /* 1111 * MADV_FREE only operates on OBJT_DEFAULT or OBJT_SWAP pages 1112 * and those pages must be OBJ_ONEMAPPING. 1113 */ 1114 if (advise == MADV_FREE) { 1115 if ((tobject->type != OBJT_DEFAULT && 1116 tobject->type != OBJT_SWAP) || 1117 (tobject->flags & OBJ_ONEMAPPING) == 0) { 1118 goto unlock_tobject; 1119 } 1120 } 1121 m = vm_page_lookup(tobject, tpindex); 1122 if (m == NULL) { 1123 /* 1124 * There may be swap even if there is no backing page 1125 */ 1126 if (advise == MADV_FREE && tobject->type == OBJT_SWAP) 1127 swap_pager_freespace(tobject, tpindex, 1); 1128 /* 1129 * next object 1130 */ 1131 backing_object = tobject->backing_object; 1132 if (backing_object == NULL) 1133 goto unlock_tobject; 1134 VM_OBJECT_LOCK(backing_object); 1135 tpindex += OFF_TO_IDX(tobject->backing_object_offset); 1136 if (tobject != object) 1137 VM_OBJECT_UNLOCK(tobject); 1138 tobject = backing_object; 1139 goto shadowlookup; 1140 } 1141 /* 1142 * If the page is busy or not in a normal active state, 1143 * we skip it. If the page is not managed there are no 1144 * page queues to mess with. Things can break if we mess 1145 * with pages in any of the below states. 1146 */ 1147 vm_page_lock_queues(); 1148 if (m->hold_count || 1149 m->wire_count || 1150 (m->flags & PG_UNMANAGED) || 1151 m->valid != VM_PAGE_BITS_ALL) { 1152 vm_page_unlock_queues(); 1153 goto unlock_tobject; 1154 } 1155 if ((m->flags & PG_BUSY) || m->busy) { 1156 vm_page_flag_set(m, PG_REFERENCED); 1157 vm_page_unlock_queues(); 1158 if (object != tobject) 1159 VM_OBJECT_UNLOCK(object); 1160 m->oflags |= VPO_WANTED; 1161 msleep(m, VM_OBJECT_MTX(tobject), PDROP | PVM, "madvpo", 0); 1162 VM_OBJECT_LOCK(object); 1163 goto relookup; 1164 } 1165 if (advise == MADV_WILLNEED) { 1166 vm_page_activate(m); 1167 } else if (advise == MADV_DONTNEED) { 1168 vm_page_dontneed(m); 1169 } else if (advise == MADV_FREE) { 1170 /* 1171 * Mark the page clean. This will allow the page 1172 * to be freed up by the system. However, such pages 1173 * are often reused quickly by malloc()/free() 1174 * so we do not do anything that would cause 1175 * a page fault if we can help it. 1176 * 1177 * Specifically, we do not try to actually free 1178 * the page now nor do we try to put it in the 1179 * cache (which would cause a page fault on reuse). 1180 * 1181 * But we do make the page is freeable as we 1182 * can without actually taking the step of unmapping 1183 * it. 1184 */ 1185 pmap_clear_modify(m); 1186 m->dirty = 0; 1187 m->act_count = 0; 1188 vm_page_dontneed(m); 1189 } 1190 vm_page_unlock_queues(); 1191 if (advise == MADV_FREE && tobject->type == OBJT_SWAP) 1192 swap_pager_freespace(tobject, tpindex, 1); 1193 unlock_tobject: 1194 if (tobject != object) 1195 VM_OBJECT_UNLOCK(tobject); 1196 } 1197 VM_OBJECT_UNLOCK(object); 1198 } 1199 1200 /* 1201 * vm_object_shadow: 1202 * 1203 * Create a new object which is backed by the 1204 * specified existing object range. The source 1205 * object reference is deallocated. 1206 * 1207 * The new object and offset into that object 1208 * are returned in the source parameters. 1209 */ 1210 void 1211 vm_object_shadow( 1212 vm_object_t *object, /* IN/OUT */ 1213 vm_ooffset_t *offset, /* IN/OUT */ 1214 vm_size_t length) 1215 { 1216 vm_object_t source; 1217 vm_object_t result; 1218 1219 source = *object; 1220 1221 /* 1222 * Don't create the new object if the old object isn't shared. 1223 */ 1224 if (source != NULL) { 1225 VM_OBJECT_LOCK(source); 1226 if (source->ref_count == 1 && 1227 source->handle == NULL && 1228 (source->type == OBJT_DEFAULT || 1229 source->type == OBJT_SWAP)) { 1230 VM_OBJECT_UNLOCK(source); 1231 return; 1232 } 1233 VM_OBJECT_UNLOCK(source); 1234 } 1235 1236 /* 1237 * Allocate a new object with the given length. 1238 */ 1239 result = vm_object_allocate(OBJT_DEFAULT, length); 1240 1241 /* 1242 * The new object shadows the source object, adding a reference to it. 1243 * Our caller changes his reference to point to the new object, 1244 * removing a reference to the source object. Net result: no change 1245 * of reference count. 1246 * 1247 * Try to optimize the result object's page color when shadowing 1248 * in order to maintain page coloring consistency in the combined 1249 * shadowed object. 1250 */ 1251 result->backing_object = source; 1252 /* 1253 * Store the offset into the source object, and fix up the offset into 1254 * the new object. 1255 */ 1256 result->backing_object_offset = *offset; 1257 if (source != NULL) { 1258 VM_OBJECT_LOCK(source); 1259 LIST_INSERT_HEAD(&source->shadow_head, result, shadow_list); 1260 source->shadow_count++; 1261 source->generation++; 1262 if (length < source->size) 1263 length = source->size; 1264 if (length > PQ_MAXLENGTH || source->generation > 1) 1265 length = PQ_MAXLENGTH; 1266 result->pg_color = (source->pg_color + 1267 length * source->generation) & PQ_COLORMASK; 1268 result->flags |= source->flags & OBJ_NEEDGIANT; 1269 VM_OBJECT_UNLOCK(source); 1270 next_index = (result->pg_color + PQ_MAXLENGTH) & PQ_COLORMASK; 1271 } 1272 1273 1274 /* 1275 * Return the new things 1276 */ 1277 *offset = 0; 1278 *object = result; 1279 } 1280 1281 /* 1282 * vm_object_split: 1283 * 1284 * Split the pages in a map entry into a new object. This affords 1285 * easier removal of unused pages, and keeps object inheritance from 1286 * being a negative impact on memory usage. 1287 */ 1288 void 1289 vm_object_split(vm_map_entry_t entry) 1290 { 1291 vm_page_t m; 1292 vm_object_t orig_object, new_object, source; 1293 vm_pindex_t offidxstart, offidxend; 1294 vm_size_t idx, size; 1295 1296 orig_object = entry->object.vm_object; 1297 if (orig_object->type != OBJT_DEFAULT && orig_object->type != OBJT_SWAP) 1298 return; 1299 if (orig_object->ref_count <= 1) 1300 return; 1301 VM_OBJECT_UNLOCK(orig_object); 1302 1303 offidxstart = OFF_TO_IDX(entry->offset); 1304 offidxend = offidxstart + OFF_TO_IDX(entry->end - entry->start); 1305 size = offidxend - offidxstart; 1306 1307 /* 1308 * If swap_pager_copy() is later called, it will convert new_object 1309 * into a swap object. 1310 */ 1311 new_object = vm_object_allocate(OBJT_DEFAULT, size); 1312 1313 VM_OBJECT_LOCK(new_object); 1314 VM_OBJECT_LOCK(orig_object); 1315 source = orig_object->backing_object; 1316 if (source != NULL) { 1317 VM_OBJECT_LOCK(source); 1318 LIST_INSERT_HEAD(&source->shadow_head, 1319 new_object, shadow_list); 1320 source->shadow_count++; 1321 source->generation++; 1322 vm_object_reference_locked(source); /* for new_object */ 1323 vm_object_clear_flag(source, OBJ_ONEMAPPING); 1324 VM_OBJECT_UNLOCK(source); 1325 new_object->backing_object_offset = 1326 orig_object->backing_object_offset + entry->offset; 1327 new_object->backing_object = source; 1328 } 1329 new_object->flags |= orig_object->flags & OBJ_NEEDGIANT; 1330 vm_page_lock_queues(); 1331 for (idx = 0; idx < size; idx++) { 1332 retry: 1333 m = vm_page_lookup(orig_object, offidxstart + idx); 1334 if (m == NULL) 1335 continue; 1336 1337 /* 1338 * We must wait for pending I/O to complete before we can 1339 * rename the page. 1340 * 1341 * We do not have to VM_PROT_NONE the page as mappings should 1342 * not be changed by this operation. 1343 */ 1344 if ((m->flags & PG_BUSY) || m->busy) { 1345 vm_page_flag_set(m, PG_REFERENCED); 1346 vm_page_unlock_queues(); 1347 VM_OBJECT_UNLOCK(new_object); 1348 m->oflags |= VPO_WANTED; 1349 msleep(m, VM_OBJECT_MTX(orig_object), PDROP | PVM, "spltwt", 0); 1350 VM_OBJECT_LOCK(new_object); 1351 VM_OBJECT_LOCK(orig_object); 1352 vm_page_lock_queues(); 1353 goto retry; 1354 } 1355 vm_page_rename(m, new_object, idx); 1356 /* page automatically made dirty by rename and cache handled */ 1357 vm_page_busy(m); 1358 } 1359 vm_page_unlock_queues(); 1360 if (orig_object->type == OBJT_SWAP) { 1361 /* 1362 * swap_pager_copy() can sleep, in which case the orig_object's 1363 * and new_object's locks are released and reacquired. 1364 */ 1365 swap_pager_copy(orig_object, new_object, offidxstart, 0); 1366 } 1367 VM_OBJECT_UNLOCK(orig_object); 1368 vm_page_lock_queues(); 1369 TAILQ_FOREACH(m, &new_object->memq, listq) 1370 vm_page_wakeup(m); 1371 vm_page_unlock_queues(); 1372 VM_OBJECT_UNLOCK(new_object); 1373 entry->object.vm_object = new_object; 1374 entry->offset = 0LL; 1375 vm_object_deallocate(orig_object); 1376 VM_OBJECT_LOCK(new_object); 1377 } 1378 1379 #define OBSC_TEST_ALL_SHADOWED 0x0001 1380 #define OBSC_COLLAPSE_NOWAIT 0x0002 1381 #define OBSC_COLLAPSE_WAIT 0x0004 1382 1383 static int 1384 vm_object_backing_scan(vm_object_t object, int op) 1385 { 1386 int r = 1; 1387 vm_page_t p; 1388 vm_object_t backing_object; 1389 vm_pindex_t backing_offset_index; 1390 1391 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1392 VM_OBJECT_LOCK_ASSERT(object->backing_object, MA_OWNED); 1393 1394 backing_object = object->backing_object; 1395 backing_offset_index = OFF_TO_IDX(object->backing_object_offset); 1396 1397 /* 1398 * Initial conditions 1399 */ 1400 if (op & OBSC_TEST_ALL_SHADOWED) { 1401 /* 1402 * We do not want to have to test for the existence of 1403 * swap pages in the backing object. XXX but with the 1404 * new swapper this would be pretty easy to do. 1405 * 1406 * XXX what about anonymous MAP_SHARED memory that hasn't 1407 * been ZFOD faulted yet? If we do not test for this, the 1408 * shadow test may succeed! XXX 1409 */ 1410 if (backing_object->type != OBJT_DEFAULT) { 1411 return (0); 1412 } 1413 } 1414 if (op & OBSC_COLLAPSE_WAIT) { 1415 vm_object_set_flag(backing_object, OBJ_DEAD); 1416 } 1417 1418 /* 1419 * Our scan 1420 */ 1421 p = TAILQ_FIRST(&backing_object->memq); 1422 while (p) { 1423 vm_page_t next = TAILQ_NEXT(p, listq); 1424 vm_pindex_t new_pindex = p->pindex - backing_offset_index; 1425 1426 if (op & OBSC_TEST_ALL_SHADOWED) { 1427 vm_page_t pp; 1428 1429 /* 1430 * Ignore pages outside the parent object's range 1431 * and outside the parent object's mapping of the 1432 * backing object. 1433 * 1434 * note that we do not busy the backing object's 1435 * page. 1436 */ 1437 if ( 1438 p->pindex < backing_offset_index || 1439 new_pindex >= object->size 1440 ) { 1441 p = next; 1442 continue; 1443 } 1444 1445 /* 1446 * See if the parent has the page or if the parent's 1447 * object pager has the page. If the parent has the 1448 * page but the page is not valid, the parent's 1449 * object pager must have the page. 1450 * 1451 * If this fails, the parent does not completely shadow 1452 * the object and we might as well give up now. 1453 */ 1454 1455 pp = vm_page_lookup(object, new_pindex); 1456 if ( 1457 (pp == NULL || pp->valid == 0) && 1458 !vm_pager_has_page(object, new_pindex, NULL, NULL) 1459 ) { 1460 r = 0; 1461 break; 1462 } 1463 } 1464 1465 /* 1466 * Check for busy page 1467 */ 1468 if (op & (OBSC_COLLAPSE_WAIT | OBSC_COLLAPSE_NOWAIT)) { 1469 vm_page_t pp; 1470 1471 if (op & OBSC_COLLAPSE_NOWAIT) { 1472 if ((p->flags & PG_BUSY) || 1473 !p->valid || 1474 p->busy) { 1475 p = next; 1476 continue; 1477 } 1478 } else if (op & OBSC_COLLAPSE_WAIT) { 1479 if ((p->flags & PG_BUSY) || p->busy) { 1480 vm_page_lock_queues(); 1481 vm_page_flag_set(p, PG_REFERENCED); 1482 vm_page_unlock_queues(); 1483 VM_OBJECT_UNLOCK(object); 1484 p->oflags |= VPO_WANTED; 1485 msleep(p, VM_OBJECT_MTX(backing_object), 1486 PDROP | PVM, "vmocol", 0); 1487 VM_OBJECT_LOCK(object); 1488 VM_OBJECT_LOCK(backing_object); 1489 /* 1490 * If we slept, anything could have 1491 * happened. Since the object is 1492 * marked dead, the backing offset 1493 * should not have changed so we 1494 * just restart our scan. 1495 */ 1496 p = TAILQ_FIRST(&backing_object->memq); 1497 continue; 1498 } 1499 } 1500 1501 KASSERT( 1502 p->object == backing_object, 1503 ("vm_object_backing_scan: object mismatch") 1504 ); 1505 1506 /* 1507 * Destroy any associated swap 1508 */ 1509 if (backing_object->type == OBJT_SWAP) { 1510 swap_pager_freespace( 1511 backing_object, 1512 p->pindex, 1513 1 1514 ); 1515 } 1516 1517 if ( 1518 p->pindex < backing_offset_index || 1519 new_pindex >= object->size 1520 ) { 1521 /* 1522 * Page is out of the parent object's range, we 1523 * can simply destroy it. 1524 */ 1525 vm_page_lock_queues(); 1526 KASSERT(!pmap_page_is_mapped(p), 1527 ("freeing mapped page %p", p)); 1528 if (p->wire_count == 0) 1529 vm_page_free(p); 1530 else 1531 vm_page_remove(p); 1532 vm_page_unlock_queues(); 1533 p = next; 1534 continue; 1535 } 1536 1537 pp = vm_page_lookup(object, new_pindex); 1538 if ( 1539 pp != NULL || 1540 vm_pager_has_page(object, new_pindex, NULL, NULL) 1541 ) { 1542 /* 1543 * page already exists in parent OR swap exists 1544 * for this location in the parent. Destroy 1545 * the original page from the backing object. 1546 * 1547 * Leave the parent's page alone 1548 */ 1549 vm_page_lock_queues(); 1550 KASSERT(!pmap_page_is_mapped(p), 1551 ("freeing mapped page %p", p)); 1552 if (p->wire_count == 0) 1553 vm_page_free(p); 1554 else 1555 vm_page_remove(p); 1556 vm_page_unlock_queues(); 1557 p = next; 1558 continue; 1559 } 1560 1561 /* 1562 * Page does not exist in parent, rename the 1563 * page from the backing object to the main object. 1564 * 1565 * If the page was mapped to a process, it can remain 1566 * mapped through the rename. 1567 */ 1568 vm_page_lock_queues(); 1569 vm_page_rename(p, object, new_pindex); 1570 vm_page_unlock_queues(); 1571 /* page automatically made dirty by rename */ 1572 } 1573 p = next; 1574 } 1575 return (r); 1576 } 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 static void 1585 vm_object_qcollapse(vm_object_t object) 1586 { 1587 vm_object_t backing_object = object->backing_object; 1588 1589 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1590 VM_OBJECT_LOCK_ASSERT(backing_object, MA_OWNED); 1591 1592 if (backing_object->ref_count != 1) 1593 return; 1594 1595 vm_object_backing_scan(object, OBSC_COLLAPSE_NOWAIT); 1596 } 1597 1598 /* 1599 * vm_object_collapse: 1600 * 1601 * Collapse an object with the object backing it. 1602 * Pages in the backing object are moved into the 1603 * parent, and the backing object is deallocated. 1604 */ 1605 void 1606 vm_object_collapse(vm_object_t object) 1607 { 1608 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1609 1610 while (TRUE) { 1611 vm_object_t backing_object; 1612 1613 /* 1614 * Verify that the conditions are right for collapse: 1615 * 1616 * The object exists and the backing object exists. 1617 */ 1618 if ((backing_object = object->backing_object) == NULL) 1619 break; 1620 1621 /* 1622 * we check the backing object first, because it is most likely 1623 * not collapsable. 1624 */ 1625 VM_OBJECT_LOCK(backing_object); 1626 if (backing_object->handle != NULL || 1627 (backing_object->type != OBJT_DEFAULT && 1628 backing_object->type != OBJT_SWAP) || 1629 (backing_object->flags & OBJ_DEAD) || 1630 object->handle != NULL || 1631 (object->type != OBJT_DEFAULT && 1632 object->type != OBJT_SWAP) || 1633 (object->flags & OBJ_DEAD)) { 1634 VM_OBJECT_UNLOCK(backing_object); 1635 break; 1636 } 1637 1638 if ( 1639 object->paging_in_progress != 0 || 1640 backing_object->paging_in_progress != 0 1641 ) { 1642 vm_object_qcollapse(object); 1643 VM_OBJECT_UNLOCK(backing_object); 1644 break; 1645 } 1646 /* 1647 * We know that we can either collapse the backing object (if 1648 * the parent is the only reference to it) or (perhaps) have 1649 * the parent bypass the object if the parent happens to shadow 1650 * all the resident pages in the entire backing object. 1651 * 1652 * This is ignoring pager-backed pages such as swap pages. 1653 * vm_object_backing_scan fails the shadowing test in this 1654 * case. 1655 */ 1656 if (backing_object->ref_count == 1) { 1657 /* 1658 * If there is exactly one reference to the backing 1659 * object, we can collapse it into the parent. 1660 */ 1661 vm_object_backing_scan(object, OBSC_COLLAPSE_WAIT); 1662 1663 /* 1664 * Move the pager from backing_object to object. 1665 */ 1666 if (backing_object->type == OBJT_SWAP) { 1667 /* 1668 * swap_pager_copy() can sleep, in which case 1669 * the backing_object's and object's locks are 1670 * released and reacquired. 1671 */ 1672 swap_pager_copy( 1673 backing_object, 1674 object, 1675 OFF_TO_IDX(object->backing_object_offset), TRUE); 1676 } 1677 /* 1678 * Object now shadows whatever backing_object did. 1679 * Note that the reference to 1680 * backing_object->backing_object moves from within 1681 * backing_object to within object. 1682 */ 1683 LIST_REMOVE(object, shadow_list); 1684 backing_object->shadow_count--; 1685 backing_object->generation++; 1686 if (backing_object->backing_object) { 1687 VM_OBJECT_LOCK(backing_object->backing_object); 1688 LIST_REMOVE(backing_object, shadow_list); 1689 LIST_INSERT_HEAD( 1690 &backing_object->backing_object->shadow_head, 1691 object, shadow_list); 1692 /* 1693 * The shadow_count has not changed. 1694 */ 1695 backing_object->backing_object->generation++; 1696 VM_OBJECT_UNLOCK(backing_object->backing_object); 1697 } 1698 object->backing_object = backing_object->backing_object; 1699 object->backing_object_offset += 1700 backing_object->backing_object_offset; 1701 1702 /* 1703 * Discard backing_object. 1704 * 1705 * Since the backing object has no pages, no pager left, 1706 * and no object references within it, all that is 1707 * necessary is to dispose of it. 1708 */ 1709 KASSERT(backing_object->ref_count == 1, ("backing_object %p was somehow re-referenced during collapse!", backing_object)); 1710 VM_OBJECT_UNLOCK(backing_object); 1711 1712 mtx_lock(&vm_object_list_mtx); 1713 TAILQ_REMOVE( 1714 &vm_object_list, 1715 backing_object, 1716 object_list 1717 ); 1718 mtx_unlock(&vm_object_list_mtx); 1719 1720 uma_zfree(obj_zone, backing_object); 1721 1722 object_collapses++; 1723 } else { 1724 vm_object_t new_backing_object; 1725 1726 /* 1727 * If we do not entirely shadow the backing object, 1728 * there is nothing we can do so we give up. 1729 */ 1730 if (object->resident_page_count != object->size && 1731 vm_object_backing_scan(object, 1732 OBSC_TEST_ALL_SHADOWED) == 0) { 1733 VM_OBJECT_UNLOCK(backing_object); 1734 break; 1735 } 1736 1737 /* 1738 * Make the parent shadow the next object in the 1739 * chain. Deallocating backing_object will not remove 1740 * it, since its reference count is at least 2. 1741 */ 1742 LIST_REMOVE(object, shadow_list); 1743 backing_object->shadow_count--; 1744 backing_object->generation++; 1745 1746 new_backing_object = backing_object->backing_object; 1747 if ((object->backing_object = new_backing_object) != NULL) { 1748 VM_OBJECT_LOCK(new_backing_object); 1749 LIST_INSERT_HEAD( 1750 &new_backing_object->shadow_head, 1751 object, 1752 shadow_list 1753 ); 1754 new_backing_object->shadow_count++; 1755 new_backing_object->generation++; 1756 vm_object_reference_locked(new_backing_object); 1757 VM_OBJECT_UNLOCK(new_backing_object); 1758 object->backing_object_offset += 1759 backing_object->backing_object_offset; 1760 } 1761 1762 /* 1763 * Drop the reference count on backing_object. Since 1764 * its ref_count was at least 2, it will not vanish. 1765 */ 1766 backing_object->ref_count--; 1767 VM_OBJECT_UNLOCK(backing_object); 1768 object_bypasses++; 1769 } 1770 1771 /* 1772 * Try again with this object's new backing object. 1773 */ 1774 } 1775 } 1776 1777 /* 1778 * vm_object_page_remove: 1779 * 1780 * Removes all physical pages in the given range from the 1781 * object's list of pages. If the range's end is zero, all 1782 * physical pages from the range's start to the end of the object 1783 * are deleted. 1784 * 1785 * The object must be locked. 1786 */ 1787 void 1788 vm_object_page_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end, 1789 boolean_t clean_only) 1790 { 1791 vm_page_t p, next; 1792 1793 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1794 if (object->resident_page_count == 0) 1795 return; 1796 1797 /* 1798 * Since physically-backed objects do not use managed pages, we can't 1799 * remove pages from the object (we must instead remove the page 1800 * references, and then destroy the object). 1801 */ 1802 KASSERT(object->type != OBJT_PHYS, 1803 ("attempt to remove pages from a physical object")); 1804 1805 vm_object_pip_add(object, 1); 1806 again: 1807 vm_page_lock_queues(); 1808 if ((p = TAILQ_FIRST(&object->memq)) != NULL) { 1809 if (p->pindex < start) { 1810 p = vm_page_splay(start, object->root); 1811 if ((object->root = p)->pindex < start) 1812 p = TAILQ_NEXT(p, listq); 1813 } 1814 } 1815 /* 1816 * Assert: the variable p is either (1) the page with the 1817 * least pindex greater than or equal to the parameter pindex 1818 * or (2) NULL. 1819 */ 1820 for (; 1821 p != NULL && (p->pindex < end || end == 0); 1822 p = next) { 1823 next = TAILQ_NEXT(p, listq); 1824 1825 if (p->wire_count != 0) { 1826 pmap_remove_all(p); 1827 if (!clean_only) 1828 p->valid = 0; 1829 continue; 1830 } 1831 if (vm_page_sleep_if_busy(p, TRUE, "vmopar")) 1832 goto again; 1833 if (clean_only && p->valid) { 1834 pmap_remove_write(p); 1835 if (p->valid & p->dirty) 1836 continue; 1837 } 1838 pmap_remove_all(p); 1839 vm_page_free(p); 1840 } 1841 vm_page_unlock_queues(); 1842 vm_object_pip_wakeup(object); 1843 } 1844 1845 /* 1846 * Routine: vm_object_coalesce 1847 * Function: Coalesces two objects backing up adjoining 1848 * regions of memory into a single object. 1849 * 1850 * returns TRUE if objects were combined. 1851 * 1852 * NOTE: Only works at the moment if the second object is NULL - 1853 * if it's not, which object do we lock first? 1854 * 1855 * Parameters: 1856 * prev_object First object to coalesce 1857 * prev_offset Offset into prev_object 1858 * prev_size Size of reference to prev_object 1859 * next_size Size of reference to the second object 1860 * 1861 * Conditions: 1862 * The object must *not* be locked. 1863 */ 1864 boolean_t 1865 vm_object_coalesce(vm_object_t prev_object, vm_ooffset_t prev_offset, 1866 vm_size_t prev_size, vm_size_t next_size) 1867 { 1868 vm_pindex_t next_pindex; 1869 1870 if (prev_object == NULL) 1871 return (TRUE); 1872 VM_OBJECT_LOCK(prev_object); 1873 if (prev_object->type != OBJT_DEFAULT && 1874 prev_object->type != OBJT_SWAP) { 1875 VM_OBJECT_UNLOCK(prev_object); 1876 return (FALSE); 1877 } 1878 1879 /* 1880 * Try to collapse the object first 1881 */ 1882 vm_object_collapse(prev_object); 1883 1884 /* 1885 * Can't coalesce if: . more than one reference . paged out . shadows 1886 * another object . has a copy elsewhere (any of which mean that the 1887 * pages not mapped to prev_entry may be in use anyway) 1888 */ 1889 if (prev_object->backing_object != NULL) { 1890 VM_OBJECT_UNLOCK(prev_object); 1891 return (FALSE); 1892 } 1893 1894 prev_size >>= PAGE_SHIFT; 1895 next_size >>= PAGE_SHIFT; 1896 next_pindex = OFF_TO_IDX(prev_offset) + prev_size; 1897 1898 if ((prev_object->ref_count > 1) && 1899 (prev_object->size != next_pindex)) { 1900 VM_OBJECT_UNLOCK(prev_object); 1901 return (FALSE); 1902 } 1903 1904 /* 1905 * Remove any pages that may still be in the object from a previous 1906 * deallocation. 1907 */ 1908 if (next_pindex < prev_object->size) { 1909 vm_object_page_remove(prev_object, 1910 next_pindex, 1911 next_pindex + next_size, FALSE); 1912 if (prev_object->type == OBJT_SWAP) 1913 swap_pager_freespace(prev_object, 1914 next_pindex, next_size); 1915 } 1916 1917 /* 1918 * Extend the object if necessary. 1919 */ 1920 if (next_pindex + next_size > prev_object->size) 1921 prev_object->size = next_pindex + next_size; 1922 1923 VM_OBJECT_UNLOCK(prev_object); 1924 return (TRUE); 1925 } 1926 1927 void 1928 vm_object_set_writeable_dirty(vm_object_t object) 1929 { 1930 struct vnode *vp; 1931 1932 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1933 if ((object->flags & OBJ_MIGHTBEDIRTY) != 0) 1934 return; 1935 vm_object_set_flag(object, OBJ_MIGHTBEDIRTY); 1936 if (object->type == OBJT_VNODE && 1937 (vp = (struct vnode *)object->handle) != NULL) { 1938 VI_LOCK(vp); 1939 vp->v_iflag |= VI_OBJDIRTY; 1940 VI_UNLOCK(vp); 1941 } 1942 } 1943 1944 #include "opt_ddb.h" 1945 #ifdef DDB 1946 #include <sys/kernel.h> 1947 1948 #include <sys/cons.h> 1949 1950 #include <ddb/ddb.h> 1951 1952 static int 1953 _vm_object_in_map(vm_map_t map, vm_object_t object, vm_map_entry_t entry) 1954 { 1955 vm_map_t tmpm; 1956 vm_map_entry_t tmpe; 1957 vm_object_t obj; 1958 int entcount; 1959 1960 if (map == 0) 1961 return 0; 1962 1963 if (entry == 0) { 1964 tmpe = map->header.next; 1965 entcount = map->nentries; 1966 while (entcount-- && (tmpe != &map->header)) { 1967 if (_vm_object_in_map(map, object, tmpe)) { 1968 return 1; 1969 } 1970 tmpe = tmpe->next; 1971 } 1972 } else if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) { 1973 tmpm = entry->object.sub_map; 1974 tmpe = tmpm->header.next; 1975 entcount = tmpm->nentries; 1976 while (entcount-- && tmpe != &tmpm->header) { 1977 if (_vm_object_in_map(tmpm, object, tmpe)) { 1978 return 1; 1979 } 1980 tmpe = tmpe->next; 1981 } 1982 } else if ((obj = entry->object.vm_object) != NULL) { 1983 for (; obj; obj = obj->backing_object) 1984 if (obj == object) { 1985 return 1; 1986 } 1987 } 1988 return 0; 1989 } 1990 1991 static int 1992 vm_object_in_map(vm_object_t object) 1993 { 1994 struct proc *p; 1995 1996 /* sx_slock(&allproc_lock); */ 1997 LIST_FOREACH(p, &allproc, p_list) { 1998 if (!p->p_vmspace /* || (p->p_flag & (P_SYSTEM|P_WEXIT)) */) 1999 continue; 2000 if (_vm_object_in_map(&p->p_vmspace->vm_map, object, 0)) { 2001 /* sx_sunlock(&allproc_lock); */ 2002 return 1; 2003 } 2004 } 2005 /* sx_sunlock(&allproc_lock); */ 2006 if (_vm_object_in_map(kernel_map, object, 0)) 2007 return 1; 2008 if (_vm_object_in_map(kmem_map, object, 0)) 2009 return 1; 2010 if (_vm_object_in_map(pager_map, object, 0)) 2011 return 1; 2012 if (_vm_object_in_map(buffer_map, object, 0)) 2013 return 1; 2014 return 0; 2015 } 2016 2017 DB_SHOW_COMMAND(vmochk, vm_object_check) 2018 { 2019 vm_object_t object; 2020 2021 /* 2022 * make sure that internal objs are in a map somewhere 2023 * and none have zero ref counts. 2024 */ 2025 TAILQ_FOREACH(object, &vm_object_list, object_list) { 2026 if (object->handle == NULL && 2027 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) { 2028 if (object->ref_count == 0) { 2029 db_printf("vmochk: internal obj has zero ref count: %ld\n", 2030 (long)object->size); 2031 } 2032 if (!vm_object_in_map(object)) { 2033 db_printf( 2034 "vmochk: internal obj is not in a map: " 2035 "ref: %d, size: %lu: 0x%lx, backing_object: %p\n", 2036 object->ref_count, (u_long)object->size, 2037 (u_long)object->size, 2038 (void *)object->backing_object); 2039 } 2040 } 2041 } 2042 } 2043 2044 /* 2045 * vm_object_print: [ debug ] 2046 */ 2047 DB_SHOW_COMMAND(object, vm_object_print_static) 2048 { 2049 /* XXX convert args. */ 2050 vm_object_t object = (vm_object_t)addr; 2051 boolean_t full = have_addr; 2052 2053 vm_page_t p; 2054 2055 /* XXX count is an (unused) arg. Avoid shadowing it. */ 2056 #define count was_count 2057 2058 int count; 2059 2060 if (object == NULL) 2061 return; 2062 2063 db_iprintf( 2064 "Object %p: type=%d, size=0x%jx, res=%d, ref=%d, flags=0x%x\n", 2065 object, (int)object->type, (uintmax_t)object->size, 2066 object->resident_page_count, object->ref_count, object->flags); 2067 db_iprintf(" sref=%d, backing_object(%d)=(%p)+0x%jx\n", 2068 object->shadow_count, 2069 object->backing_object ? object->backing_object->ref_count : 0, 2070 object->backing_object, (uintmax_t)object->backing_object_offset); 2071 2072 if (!full) 2073 return; 2074 2075 db_indent += 2; 2076 count = 0; 2077 TAILQ_FOREACH(p, &object->memq, listq) { 2078 if (count == 0) 2079 db_iprintf("memory:="); 2080 else if (count == 6) { 2081 db_printf("\n"); 2082 db_iprintf(" ..."); 2083 count = 0; 2084 } else 2085 db_printf(","); 2086 count++; 2087 2088 db_printf("(off=0x%jx,page=0x%jx)", 2089 (uintmax_t)p->pindex, (uintmax_t)VM_PAGE_TO_PHYS(p)); 2090 } 2091 if (count != 0) 2092 db_printf("\n"); 2093 db_indent -= 2; 2094 } 2095 2096 /* XXX. */ 2097 #undef count 2098 2099 /* XXX need this non-static entry for calling from vm_map_print. */ 2100 void 2101 vm_object_print( 2102 /* db_expr_t */ long addr, 2103 boolean_t have_addr, 2104 /* db_expr_t */ long count, 2105 char *modif) 2106 { 2107 vm_object_print_static(addr, have_addr, count, modif); 2108 } 2109 2110 DB_SHOW_COMMAND(vmopag, vm_object_print_pages) 2111 { 2112 vm_object_t object; 2113 int nl = 0; 2114 int c; 2115 2116 TAILQ_FOREACH(object, &vm_object_list, object_list) { 2117 vm_pindex_t idx, fidx; 2118 vm_pindex_t osize; 2119 vm_paddr_t pa = -1, padiff; 2120 int rcount; 2121 vm_page_t m; 2122 2123 db_printf("new object: %p\n", (void *)object); 2124 if (nl > 18) { 2125 c = cngetc(); 2126 if (c != ' ') 2127 return; 2128 nl = 0; 2129 } 2130 nl++; 2131 rcount = 0; 2132 fidx = 0; 2133 osize = object->size; 2134 if (osize > 128) 2135 osize = 128; 2136 for (idx = 0; idx < osize; idx++) { 2137 m = vm_page_lookup(object, idx); 2138 if (m == NULL) { 2139 if (rcount) { 2140 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2141 (long)fidx, rcount, (long)pa); 2142 if (nl > 18) { 2143 c = cngetc(); 2144 if (c != ' ') 2145 return; 2146 nl = 0; 2147 } 2148 nl++; 2149 rcount = 0; 2150 } 2151 continue; 2152 } 2153 2154 2155 if (rcount && 2156 (VM_PAGE_TO_PHYS(m) == pa + rcount * PAGE_SIZE)) { 2157 ++rcount; 2158 continue; 2159 } 2160 if (rcount) { 2161 padiff = pa + rcount * PAGE_SIZE - VM_PAGE_TO_PHYS(m); 2162 padiff >>= PAGE_SHIFT; 2163 padiff &= PQ_COLORMASK; 2164 if (padiff == 0) { 2165 pa = VM_PAGE_TO_PHYS(m) - rcount * PAGE_SIZE; 2166 ++rcount; 2167 continue; 2168 } 2169 db_printf(" index(%ld)run(%d)pa(0x%lx)", 2170 (long)fidx, rcount, (long)pa); 2171 db_printf("pd(%ld)\n", (long)padiff); 2172 if (nl > 18) { 2173 c = cngetc(); 2174 if (c != ' ') 2175 return; 2176 nl = 0; 2177 } 2178 nl++; 2179 } 2180 fidx = idx; 2181 pa = VM_PAGE_TO_PHYS(m); 2182 rcount = 1; 2183 } 2184 if (rcount) { 2185 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2186 (long)fidx, rcount, (long)pa); 2187 if (nl > 18) { 2188 c = cngetc(); 2189 if (c != ' ') 2190 return; 2191 nl = 0; 2192 } 2193 nl++; 2194 } 2195 } 2196 } 2197 #endif /* DDB */ 2198