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); 113 114 /* 115 * Virtual memory objects maintain the actual data 116 * associated with allocated virtual memory. A given 117 * page of memory exists within exactly one object. 118 * 119 * An object is only deallocated when all "references" 120 * are given up. Only one "reference" to a given 121 * region of an object should be writeable. 122 * 123 * Associated with each object is a list of all resident 124 * memory pages belonging to that object; this list is 125 * maintained by the "vm_page" module, and locked by the object's 126 * lock. 127 * 128 * Each object also records a "pager" routine which is 129 * used to retrieve (and store) pages to the proper backing 130 * storage. In addition, objects may be backed by other 131 * objects from which they were virtual-copied. 132 * 133 * The only items within the object structure which are 134 * modified after time of creation are: 135 * reference count locked by object's lock 136 * pager routine locked by object's lock 137 * 138 */ 139 140 struct object_q vm_object_list; 141 struct mtx vm_object_list_mtx; /* lock for object list and count */ 142 143 struct vm_object kernel_object_store; 144 struct vm_object kmem_object_store; 145 146 static long object_collapses; 147 static long object_bypasses; 148 149 /* 150 * next_index determines the page color that is assigned to the next 151 * allocated object. Accesses to next_index are not synchronized 152 * because the effects of two or more object allocations using 153 * next_index simultaneously are inconsequential. At any given time, 154 * numerous objects have the same page color. 155 */ 156 static int next_index; 157 158 static uma_zone_t obj_zone; 159 #define VM_OBJECTS_INIT 256 160 161 static int vm_object_zinit(void *mem, int size, int flags); 162 163 #ifdef INVARIANTS 164 static void vm_object_zdtor(void *mem, int size, void *arg); 165 166 static void 167 vm_object_zdtor(void *mem, int size, void *arg) 168 { 169 vm_object_t object; 170 171 object = (vm_object_t)mem; 172 KASSERT(TAILQ_EMPTY(&object->memq), 173 ("object %p has resident pages", 174 object)); 175 KASSERT(object->paging_in_progress == 0, 176 ("object %p paging_in_progress = %d", 177 object, object->paging_in_progress)); 178 KASSERT(object->resident_page_count == 0, 179 ("object %p resident_page_count = %d", 180 object, object->resident_page_count)); 181 KASSERT(object->shadow_count == 0, 182 ("object %p shadow_count = %d", 183 object, object->shadow_count)); 184 } 185 #endif 186 187 static int 188 vm_object_zinit(void *mem, int size, int flags) 189 { 190 vm_object_t object; 191 192 object = (vm_object_t)mem; 193 bzero(&object->mtx, sizeof(object->mtx)); 194 VM_OBJECT_LOCK_INIT(object, "standard object"); 195 196 /* These are true for any object that has been freed */ 197 object->paging_in_progress = 0; 198 object->resident_page_count = 0; 199 object->shadow_count = 0; 200 return (0); 201 } 202 203 void 204 _vm_object_allocate(objtype_t type, vm_pindex_t size, vm_object_t object) 205 { 206 int incr; 207 208 TAILQ_INIT(&object->memq); 209 LIST_INIT(&object->shadow_head); 210 211 object->root = NULL; 212 object->type = type; 213 object->size = size; 214 object->generation = 1; 215 object->ref_count = 1; 216 object->flags = 0; 217 if ((object->type == OBJT_DEFAULT) || (object->type == OBJT_SWAP)) 218 object->flags = OBJ_ONEMAPPING; 219 if (size > (PQ_L2_SIZE / 3 + PQ_PRIME1)) 220 incr = PQ_L2_SIZE / 3 + PQ_PRIME1; 221 else 222 incr = size; 223 object->pg_color = next_index; 224 next_index = (object->pg_color + incr) & PQ_L2_MASK; 225 object->handle = NULL; 226 object->backing_object = NULL; 227 object->backing_object_offset = (vm_ooffset_t) 0; 228 229 mtx_lock(&vm_object_list_mtx); 230 TAILQ_INSERT_TAIL(&vm_object_list, object, object_list); 231 mtx_unlock(&vm_object_list_mtx); 232 } 233 234 /* 235 * vm_object_init: 236 * 237 * Initialize the VM objects module. 238 */ 239 void 240 vm_object_init(void) 241 { 242 TAILQ_INIT(&vm_object_list); 243 mtx_init(&vm_object_list_mtx, "vm object_list", NULL, MTX_DEF); 244 245 VM_OBJECT_LOCK_INIT(&kernel_object_store, "kernel object"); 246 _vm_object_allocate(OBJT_DEFAULT, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS), 247 kernel_object); 248 249 VM_OBJECT_LOCK_INIT(&kmem_object_store, "kmem object"); 250 _vm_object_allocate(OBJT_DEFAULT, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS), 251 kmem_object); 252 253 obj_zone = uma_zcreate("VM OBJECT", sizeof (struct vm_object), NULL, 254 #ifdef INVARIANTS 255 vm_object_zdtor, 256 #else 257 NULL, 258 #endif 259 vm_object_zinit, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM|UMA_ZONE_NOFREE); 260 uma_prealloc(obj_zone, VM_OBJECTS_INIT); 261 } 262 263 void 264 vm_object_clear_flag(vm_object_t object, u_short bits) 265 { 266 267 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 268 object->flags &= ~bits; 269 } 270 271 void 272 vm_object_pip_add(vm_object_t object, short i) 273 { 274 275 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 276 object->paging_in_progress += i; 277 } 278 279 void 280 vm_object_pip_subtract(vm_object_t object, short i) 281 { 282 283 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 284 object->paging_in_progress -= i; 285 } 286 287 void 288 vm_object_pip_wakeup(vm_object_t object) 289 { 290 291 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 292 object->paging_in_progress--; 293 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) { 294 vm_object_clear_flag(object, OBJ_PIPWNT); 295 wakeup(object); 296 } 297 } 298 299 void 300 vm_object_pip_wakeupn(vm_object_t object, short i) 301 { 302 303 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 304 if (i) 305 object->paging_in_progress -= i; 306 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) { 307 vm_object_clear_flag(object, OBJ_PIPWNT); 308 wakeup(object); 309 } 310 } 311 312 void 313 vm_object_pip_wait(vm_object_t object, char *waitid) 314 { 315 316 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 317 while (object->paging_in_progress) { 318 object->flags |= OBJ_PIPWNT; 319 msleep(object, VM_OBJECT_MTX(object), PVM, waitid, 0); 320 } 321 } 322 323 /* 324 * vm_object_allocate: 325 * 326 * Returns a new object with the given size. 327 */ 328 vm_object_t 329 vm_object_allocate(objtype_t type, vm_pindex_t size) 330 { 331 vm_object_t object; 332 333 object = (vm_object_t)uma_zalloc(obj_zone, M_WAITOK); 334 _vm_object_allocate(type, size, object); 335 return (object); 336 } 337 338 339 /* 340 * vm_object_reference: 341 * 342 * Gets another reference to the given object. Note: OBJ_DEAD 343 * objects can be referenced during final cleaning. 344 */ 345 void 346 vm_object_reference(vm_object_t object) 347 { 348 struct vnode *vp; 349 int flags; 350 351 if (object == NULL) 352 return; 353 VM_OBJECT_LOCK(object); 354 object->ref_count++; 355 if (object->type == OBJT_VNODE) { 356 vp = object->handle; 357 VI_LOCK(vp); 358 VM_OBJECT_UNLOCK(object); 359 for (flags = LK_INTERLOCK; vget(vp, flags, curthread); 360 flags = 0) 361 printf("vm_object_reference: delay in vget\n"); 362 } else 363 VM_OBJECT_UNLOCK(object); 364 } 365 366 /* 367 * vm_object_reference_locked: 368 * 369 * Gets another reference to the given object. 370 * 371 * The object must be locked. 372 */ 373 void 374 vm_object_reference_locked(vm_object_t object) 375 { 376 struct vnode *vp; 377 378 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 379 KASSERT((object->flags & OBJ_DEAD) == 0, 380 ("vm_object_reference_locked: dead object referenced")); 381 object->ref_count++; 382 if (object->type == OBJT_VNODE) { 383 vp = object->handle; 384 vref(vp); 385 } 386 } 387 388 /* 389 * Handle deallocating an object of type OBJT_VNODE. 390 */ 391 void 392 vm_object_vndeallocate(vm_object_t object) 393 { 394 struct vnode *vp = (struct vnode *) object->handle; 395 396 VFS_ASSERT_GIANT(vp->v_mount); 397 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 398 KASSERT(object->type == OBJT_VNODE, 399 ("vm_object_vndeallocate: not a vnode object")); 400 KASSERT(vp != NULL, ("vm_object_vndeallocate: missing vp")); 401 #ifdef INVARIANTS 402 if (object->ref_count == 0) { 403 vprint("vm_object_vndeallocate", vp); 404 panic("vm_object_vndeallocate: bad object reference count"); 405 } 406 #endif 407 408 object->ref_count--; 409 if (object->ref_count == 0) { 410 mp_fixme("Unlocked vflag access."); 411 vp->v_vflag &= ~VV_TEXT; 412 } 413 VM_OBJECT_UNLOCK(object); 414 /* 415 * vrele may need a vop lock 416 */ 417 vrele(vp); 418 } 419 420 /* 421 * vm_object_deallocate: 422 * 423 * Release a reference to the specified object, 424 * gained either through a vm_object_allocate 425 * or a vm_object_reference call. When all references 426 * are gone, storage associated with this object 427 * may be relinquished. 428 * 429 * No object may be locked. 430 */ 431 void 432 vm_object_deallocate(vm_object_t object) 433 { 434 vm_object_t temp; 435 436 while (object != NULL) { 437 int vfslocked; 438 /* 439 * In general, the object should be locked when working with 440 * its type. In this case, in order to maintain proper lock 441 * ordering, an exception is possible because a vnode-backed 442 * object never changes its type. 443 */ 444 vfslocked = 0; 445 if (object->type == OBJT_VNODE) { 446 struct vnode *vp = (struct vnode *) object->handle; 447 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 448 } 449 VM_OBJECT_LOCK(object); 450 if (object->type == OBJT_VNODE) { 451 vm_object_vndeallocate(object); 452 VFS_UNLOCK_GIANT(vfslocked); 453 return; 454 } 455 456 KASSERT(object->ref_count != 0, 457 ("vm_object_deallocate: object deallocated too many times: %d", object->type)); 458 459 /* 460 * If the reference count goes to 0 we start calling 461 * vm_object_terminate() on the object chain. 462 * A ref count of 1 may be a special case depending on the 463 * shadow count being 0 or 1. 464 */ 465 object->ref_count--; 466 if (object->ref_count > 1) { 467 VM_OBJECT_UNLOCK(object); 468 return; 469 } else if (object->ref_count == 1) { 470 if (object->shadow_count == 0) { 471 vm_object_set_flag(object, OBJ_ONEMAPPING); 472 } else if ((object->shadow_count == 1) && 473 (object->handle == NULL) && 474 (object->type == OBJT_DEFAULT || 475 object->type == OBJT_SWAP)) { 476 vm_object_t robject; 477 478 robject = LIST_FIRST(&object->shadow_head); 479 KASSERT(robject != NULL, 480 ("vm_object_deallocate: ref_count: %d, shadow_count: %d", 481 object->ref_count, 482 object->shadow_count)); 483 if (!VM_OBJECT_TRYLOCK(robject)) { 484 /* 485 * Avoid a potential deadlock. 486 */ 487 object->ref_count++; 488 VM_OBJECT_UNLOCK(object); 489 /* 490 * More likely than not the thread 491 * holding robject's lock has lower 492 * priority than the current thread. 493 * Let the lower priority thread run. 494 */ 495 tsleep(&proc0, PVM, "vmo_de", 1); 496 continue; 497 } 498 /* 499 * Collapse object into its shadow unless its 500 * shadow is dead. In that case, object will 501 * be deallocated by the thread that is 502 * deallocating its shadow. 503 */ 504 if ((robject->flags & OBJ_DEAD) == 0 && 505 (robject->handle == NULL) && 506 (robject->type == OBJT_DEFAULT || 507 robject->type == OBJT_SWAP)) { 508 509 robject->ref_count++; 510 retry: 511 if (robject->paging_in_progress) { 512 VM_OBJECT_UNLOCK(object); 513 vm_object_pip_wait(robject, 514 "objde1"); 515 VM_OBJECT_LOCK(object); 516 goto retry; 517 } else if (object->paging_in_progress) { 518 VM_OBJECT_UNLOCK(robject); 519 object->flags |= OBJ_PIPWNT; 520 msleep(object, 521 VM_OBJECT_MTX(object), 522 PDROP | PVM, "objde2", 0); 523 VM_OBJECT_LOCK(robject); 524 VM_OBJECT_LOCK(object); 525 goto retry; 526 } 527 VM_OBJECT_UNLOCK(object); 528 if (robject->ref_count == 1) { 529 robject->ref_count--; 530 object = robject; 531 goto doterm; 532 } 533 object = robject; 534 vm_object_collapse(object); 535 VM_OBJECT_UNLOCK(object); 536 continue; 537 } 538 VM_OBJECT_UNLOCK(robject); 539 } 540 VM_OBJECT_UNLOCK(object); 541 return; 542 } 543 doterm: 544 temp = object->backing_object; 545 if (temp != NULL) { 546 VM_OBJECT_LOCK(temp); 547 LIST_REMOVE(object, shadow_list); 548 temp->shadow_count--; 549 temp->generation++; 550 VM_OBJECT_UNLOCK(temp); 551 object->backing_object = NULL; 552 } 553 /* 554 * Don't double-terminate, we could be in a termination 555 * recursion due to the terminate having to sync data 556 * to disk. 557 */ 558 if ((object->flags & OBJ_DEAD) == 0) 559 vm_object_terminate(object); 560 else 561 VM_OBJECT_UNLOCK(object); 562 object = temp; 563 } 564 } 565 566 /* 567 * vm_object_terminate actually destroys the specified object, freeing 568 * up all previously used resources. 569 * 570 * The object must be locked. 571 * This routine may block. 572 */ 573 void 574 vm_object_terminate(vm_object_t object) 575 { 576 vm_page_t p; 577 578 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 579 580 /* 581 * Make sure no one uses us. 582 */ 583 vm_object_set_flag(object, OBJ_DEAD); 584 585 /* 586 * wait for the pageout daemon to be done with the object 587 */ 588 vm_object_pip_wait(object, "objtrm"); 589 590 KASSERT(!object->paging_in_progress, 591 ("vm_object_terminate: pageout in progress")); 592 593 /* 594 * Clean and free the pages, as appropriate. All references to the 595 * object are gone, so we don't need to lock it. 596 */ 597 if (object->type == OBJT_VNODE) { 598 struct vnode *vp = (struct vnode *)object->handle; 599 600 /* 601 * Clean pages and flush buffers. 602 */ 603 vm_object_page_clean(object, 0, 0, OBJPC_SYNC); 604 VM_OBJECT_UNLOCK(object); 605 606 vinvalbuf(vp, V_SAVE, NULL, 0, 0); 607 608 VM_OBJECT_LOCK(object); 609 } 610 611 KASSERT(object->ref_count == 0, 612 ("vm_object_terminate: object with references, ref_count=%d", 613 object->ref_count)); 614 615 /* 616 * Now free any remaining pages. For internal objects, this also 617 * removes them from paging queues. Don't free wired pages, just 618 * remove them from the object. 619 */ 620 vm_page_lock_queues(); 621 while ((p = TAILQ_FIRST(&object->memq)) != NULL) { 622 KASSERT(!p->busy && (p->flags & PG_BUSY) == 0, 623 ("vm_object_terminate: freeing busy page %p " 624 "p->busy = %d, p->flags %x\n", p, p->busy, p->flags)); 625 if (p->wire_count == 0) { 626 vm_page_free(p); 627 cnt.v_pfree++; 628 } else { 629 vm_page_remove(p); 630 } 631 } 632 vm_page_unlock_queues(); 633 634 /* 635 * Let the pager know object is dead. 636 */ 637 vm_pager_deallocate(object); 638 VM_OBJECT_UNLOCK(object); 639 640 /* 641 * Remove the object from the global object list. 642 */ 643 mtx_lock(&vm_object_list_mtx); 644 TAILQ_REMOVE(&vm_object_list, object, object_list); 645 mtx_unlock(&vm_object_list_mtx); 646 647 /* 648 * Free the space for the object. 649 */ 650 uma_zfree(obj_zone, object); 651 } 652 653 /* 654 * vm_object_page_clean 655 * 656 * Clean all dirty pages in the specified range of object. Leaves page 657 * on whatever queue it is currently on. If NOSYNC is set then do not 658 * write out pages with PG_NOSYNC set (originally comes from MAP_NOSYNC), 659 * leaving the object dirty. 660 * 661 * When stuffing pages asynchronously, allow clustering. XXX we need a 662 * synchronous clustering mode implementation. 663 * 664 * Odd semantics: if start == end, we clean everything. 665 * 666 * The object must be locked. 667 */ 668 void 669 vm_object_page_clean(vm_object_t object, vm_pindex_t start, vm_pindex_t end, int flags) 670 { 671 vm_page_t p, np; 672 vm_pindex_t tstart, tend; 673 vm_pindex_t pi; 674 int clearobjflags; 675 int pagerflags; 676 int curgeneration; 677 678 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 679 if (object->type != OBJT_VNODE || 680 (object->flags & OBJ_MIGHTBEDIRTY) == 0) 681 return; 682 683 pagerflags = (flags & (OBJPC_SYNC | OBJPC_INVAL)) ? VM_PAGER_PUT_SYNC : VM_PAGER_CLUSTER_OK; 684 pagerflags |= (flags & OBJPC_INVAL) ? VM_PAGER_PUT_INVAL : 0; 685 686 vm_object_set_flag(object, OBJ_CLEANING); 687 688 tstart = start; 689 if (end == 0) { 690 tend = object->size; 691 } else { 692 tend = end; 693 } 694 695 vm_page_lock_queues(); 696 /* 697 * If the caller is smart and only msync()s a range he knows is 698 * dirty, we may be able to avoid an object scan. This results in 699 * a phenominal improvement in performance. We cannot do this 700 * as a matter of course because the object may be huge - e.g. 701 * the size might be in the gigabytes or terrabytes. 702 */ 703 if (msync_flush_flags & MSYNC_FLUSH_HARDSEQ) { 704 vm_pindex_t tscan; 705 int scanlimit; 706 int scanreset; 707 708 scanreset = object->resident_page_count / EASY_SCAN_FACTOR; 709 if (scanreset < 16) 710 scanreset = 16; 711 pagerflags |= VM_PAGER_IGNORE_CLEANCHK; 712 713 scanlimit = scanreset; 714 tscan = tstart; 715 while (tscan < tend) { 716 curgeneration = object->generation; 717 p = vm_page_lookup(object, tscan); 718 if (p == NULL || p->valid == 0 || 719 (p->queue - p->pc) == PQ_CACHE) { 720 if (--scanlimit == 0) 721 break; 722 ++tscan; 723 continue; 724 } 725 vm_page_test_dirty(p); 726 if ((p->dirty & p->valid) == 0) { 727 if (--scanlimit == 0) 728 break; 729 ++tscan; 730 continue; 731 } 732 /* 733 * If we have been asked to skip nosync pages and 734 * this is a nosync page, we can't continue. 735 */ 736 if ((flags & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC)) { 737 if (--scanlimit == 0) 738 break; 739 ++tscan; 740 continue; 741 } 742 scanlimit = scanreset; 743 744 /* 745 * This returns 0 if it was unable to busy the first 746 * page (i.e. had to sleep). 747 */ 748 tscan += vm_object_page_collect_flush(object, p, curgeneration, pagerflags); 749 } 750 751 /* 752 * If everything was dirty and we flushed it successfully, 753 * and the requested range is not the entire object, we 754 * don't have to mess with CLEANCHK or MIGHTBEDIRTY and can 755 * return immediately. 756 */ 757 if (tscan >= tend && (tstart || tend < object->size)) { 758 vm_page_unlock_queues(); 759 vm_object_clear_flag(object, OBJ_CLEANING); 760 return; 761 } 762 pagerflags &= ~VM_PAGER_IGNORE_CLEANCHK; 763 } 764 765 /* 766 * Generally set CLEANCHK interlock and make the page read-only so 767 * we can then clear the object flags. 768 * 769 * However, if this is a nosync mmap then the object is likely to 770 * stay dirty so do not mess with the page and do not clear the 771 * object flags. 772 */ 773 clearobjflags = 1; 774 TAILQ_FOREACH(p, &object->memq, listq) { 775 vm_page_flag_set(p, PG_CLEANCHK); 776 if ((flags & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC)) 777 clearobjflags = 0; 778 else 779 pmap_page_protect(p, VM_PROT_READ); 780 } 781 782 if (clearobjflags && (tstart == 0) && (tend == object->size)) { 783 struct vnode *vp; 784 785 vm_object_clear_flag(object, OBJ_WRITEABLE|OBJ_MIGHTBEDIRTY); 786 if (object->type == OBJT_VNODE && 787 (vp = (struct vnode *)object->handle) != NULL) { 788 VI_LOCK(vp); 789 if (vp->v_iflag & VI_OBJDIRTY) 790 vp->v_iflag &= ~VI_OBJDIRTY; 791 VI_UNLOCK(vp); 792 } 793 } 794 795 rescan: 796 curgeneration = object->generation; 797 798 for (p = TAILQ_FIRST(&object->memq); p; p = np) { 799 int n; 800 801 np = TAILQ_NEXT(p, listq); 802 803 again: 804 pi = p->pindex; 805 if (((p->flags & PG_CLEANCHK) == 0) || 806 (pi < tstart) || (pi >= tend) || 807 (p->valid == 0) || 808 ((p->queue - p->pc) == PQ_CACHE)) { 809 vm_page_flag_clear(p, PG_CLEANCHK); 810 continue; 811 } 812 813 vm_page_test_dirty(p); 814 if ((p->dirty & p->valid) == 0) { 815 vm_page_flag_clear(p, PG_CLEANCHK); 816 continue; 817 } 818 819 /* 820 * If we have been asked to skip nosync pages and this is a 821 * nosync page, skip it. Note that the object flags were 822 * not cleared in this case so we do not have to set them. 823 */ 824 if ((flags & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC)) { 825 vm_page_flag_clear(p, PG_CLEANCHK); 826 continue; 827 } 828 829 n = vm_object_page_collect_flush(object, p, 830 curgeneration, pagerflags); 831 if (n == 0) 832 goto rescan; 833 834 if (object->generation != curgeneration) 835 goto rescan; 836 837 /* 838 * Try to optimize the next page. If we can't we pick up 839 * our (random) scan where we left off. 840 */ 841 if (msync_flush_flags & MSYNC_FLUSH_SOFTSEQ) { 842 if ((p = vm_page_lookup(object, pi + n)) != NULL) 843 goto again; 844 } 845 } 846 vm_page_unlock_queues(); 847 #if 0 848 VOP_FSYNC(vp, (pagerflags & VM_PAGER_PUT_SYNC)?MNT_WAIT:0, curproc); 849 #endif 850 851 vm_object_clear_flag(object, OBJ_CLEANING); 852 return; 853 } 854 855 static int 856 vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int curgeneration, int pagerflags) 857 { 858 int runlen; 859 int maxf; 860 int chkb; 861 int maxb; 862 int i; 863 vm_pindex_t pi; 864 vm_page_t maf[vm_pageout_page_count]; 865 vm_page_t mab[vm_pageout_page_count]; 866 vm_page_t ma[vm_pageout_page_count]; 867 868 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 869 pi = p->pindex; 870 while (vm_page_sleep_if_busy(p, TRUE, "vpcwai")) { 871 vm_page_lock_queues(); 872 if (object->generation != curgeneration) { 873 return(0); 874 } 875 } 876 maxf = 0; 877 for(i = 1; i < vm_pageout_page_count; i++) { 878 vm_page_t tp; 879 880 if ((tp = vm_page_lookup(object, pi + i)) != NULL) { 881 if ((tp->flags & PG_BUSY) || 882 ((pagerflags & VM_PAGER_IGNORE_CLEANCHK) == 0 && 883 (tp->flags & PG_CLEANCHK) == 0) || 884 (tp->busy != 0)) 885 break; 886 if((tp->queue - tp->pc) == PQ_CACHE) { 887 vm_page_flag_clear(tp, PG_CLEANCHK); 888 break; 889 } 890 vm_page_test_dirty(tp); 891 if ((tp->dirty & tp->valid) == 0) { 892 vm_page_flag_clear(tp, PG_CLEANCHK); 893 break; 894 } 895 maf[ i - 1 ] = tp; 896 maxf++; 897 continue; 898 } 899 break; 900 } 901 902 maxb = 0; 903 chkb = vm_pageout_page_count - maxf; 904 if (chkb) { 905 for(i = 1; i < chkb;i++) { 906 vm_page_t tp; 907 908 if ((tp = vm_page_lookup(object, pi - i)) != NULL) { 909 if ((tp->flags & PG_BUSY) || 910 ((pagerflags & VM_PAGER_IGNORE_CLEANCHK) == 0 && 911 (tp->flags & PG_CLEANCHK) == 0) || 912 (tp->busy != 0)) 913 break; 914 if ((tp->queue - tp->pc) == PQ_CACHE) { 915 vm_page_flag_clear(tp, PG_CLEANCHK); 916 break; 917 } 918 vm_page_test_dirty(tp); 919 if ((tp->dirty & tp->valid) == 0) { 920 vm_page_flag_clear(tp, PG_CLEANCHK); 921 break; 922 } 923 mab[ i - 1 ] = tp; 924 maxb++; 925 continue; 926 } 927 break; 928 } 929 } 930 931 for(i = 0; i < maxb; i++) { 932 int index = (maxb - i) - 1; 933 ma[index] = mab[i]; 934 vm_page_flag_clear(ma[index], PG_CLEANCHK); 935 } 936 vm_page_flag_clear(p, PG_CLEANCHK); 937 ma[maxb] = p; 938 for(i = 0; i < maxf; i++) { 939 int index = (maxb + i) + 1; 940 ma[index] = maf[i]; 941 vm_page_flag_clear(ma[index], PG_CLEANCHK); 942 } 943 runlen = maxb + maxf + 1; 944 945 vm_pageout_flush(ma, runlen, pagerflags); 946 for (i = 0; i < runlen; i++) { 947 if (ma[i]->valid & ma[i]->dirty) { 948 pmap_page_protect(ma[i], VM_PROT_READ); 949 vm_page_flag_set(ma[i], PG_CLEANCHK); 950 951 /* 952 * maxf will end up being the actual number of pages 953 * we wrote out contiguously, non-inclusive of the 954 * first page. We do not count look-behind pages. 955 */ 956 if (i >= maxb + 1 && (maxf > i - maxb - 1)) 957 maxf = i - maxb - 1; 958 } 959 } 960 return(maxf + 1); 961 } 962 963 /* 964 * Note that there is absolutely no sense in writing out 965 * anonymous objects, so we track down the vnode object 966 * to write out. 967 * We invalidate (remove) all pages from the address space 968 * for semantic correctness. 969 * 970 * Note: certain anonymous maps, such as MAP_NOSYNC maps, 971 * may start out with a NULL object. 972 */ 973 void 974 vm_object_sync(vm_object_t object, vm_ooffset_t offset, vm_size_t size, 975 boolean_t syncio, boolean_t invalidate) 976 { 977 vm_object_t backing_object; 978 struct vnode *vp; 979 int flags; 980 981 if (object == NULL) 982 return; 983 VM_OBJECT_LOCK(object); 984 while ((backing_object = object->backing_object) != NULL) { 985 VM_OBJECT_LOCK(backing_object); 986 offset += object->backing_object_offset; 987 VM_OBJECT_UNLOCK(object); 988 object = backing_object; 989 if (object->size < OFF_TO_IDX(offset + size)) 990 size = IDX_TO_OFF(object->size) - offset; 991 } 992 /* 993 * Flush pages if writing is allowed, invalidate them 994 * if invalidation requested. Pages undergoing I/O 995 * will be ignored by vm_object_page_remove(). 996 * 997 * We cannot lock the vnode and then wait for paging 998 * to complete without deadlocking against vm_fault. 999 * Instead we simply call vm_object_page_remove() and 1000 * allow it to block internally on a page-by-page 1001 * basis when it encounters pages undergoing async 1002 * I/O. 1003 */ 1004 if (object->type == OBJT_VNODE && 1005 (object->flags & OBJ_MIGHTBEDIRTY) != 0) { 1006 int vfslocked; 1007 vp = object->handle; 1008 VM_OBJECT_UNLOCK(object); 1009 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 1010 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, curthread); 1011 flags = (syncio || invalidate) ? OBJPC_SYNC : 0; 1012 flags |= invalidate ? OBJPC_INVAL : 0; 1013 VM_OBJECT_LOCK(object); 1014 vm_object_page_clean(object, 1015 OFF_TO_IDX(offset), 1016 OFF_TO_IDX(offset + size + PAGE_MASK), 1017 flags); 1018 VM_OBJECT_UNLOCK(object); 1019 VOP_UNLOCK(vp, 0, curthread); 1020 VFS_UNLOCK_GIANT(vfslocked); 1021 VM_OBJECT_LOCK(object); 1022 } 1023 if ((object->type == OBJT_VNODE || 1024 object->type == OBJT_DEVICE) && invalidate) { 1025 boolean_t purge; 1026 purge = old_msync || (object->type == OBJT_DEVICE); 1027 vm_object_page_remove(object, 1028 OFF_TO_IDX(offset), 1029 OFF_TO_IDX(offset + size + PAGE_MASK), 1030 purge ? FALSE : TRUE); 1031 } 1032 VM_OBJECT_UNLOCK(object); 1033 } 1034 1035 /* 1036 * vm_object_madvise: 1037 * 1038 * Implements the madvise function at the object/page level. 1039 * 1040 * MADV_WILLNEED (any object) 1041 * 1042 * Activate the specified pages if they are resident. 1043 * 1044 * MADV_DONTNEED (any object) 1045 * 1046 * Deactivate the specified pages if they are resident. 1047 * 1048 * MADV_FREE (OBJT_DEFAULT/OBJT_SWAP objects, 1049 * OBJ_ONEMAPPING only) 1050 * 1051 * Deactivate and clean the specified pages if they are 1052 * resident. This permits the process to reuse the pages 1053 * without faulting or the kernel to reclaim the pages 1054 * without I/O. 1055 */ 1056 void 1057 vm_object_madvise(vm_object_t object, vm_pindex_t pindex, int count, int advise) 1058 { 1059 vm_pindex_t end, tpindex; 1060 vm_object_t backing_object, tobject; 1061 vm_page_t m; 1062 1063 if (object == NULL) 1064 return; 1065 VM_OBJECT_LOCK(object); 1066 end = pindex + count; 1067 /* 1068 * Locate and adjust resident pages 1069 */ 1070 for (; pindex < end; pindex += 1) { 1071 relookup: 1072 tobject = object; 1073 tpindex = pindex; 1074 shadowlookup: 1075 /* 1076 * MADV_FREE only operates on OBJT_DEFAULT or OBJT_SWAP pages 1077 * and those pages must be OBJ_ONEMAPPING. 1078 */ 1079 if (advise == MADV_FREE) { 1080 if ((tobject->type != OBJT_DEFAULT && 1081 tobject->type != OBJT_SWAP) || 1082 (tobject->flags & OBJ_ONEMAPPING) == 0) { 1083 goto unlock_tobject; 1084 } 1085 } 1086 m = vm_page_lookup(tobject, tpindex); 1087 if (m == NULL) { 1088 /* 1089 * There may be swap even if there is no backing page 1090 */ 1091 if (advise == MADV_FREE && tobject->type == OBJT_SWAP) 1092 swap_pager_freespace(tobject, tpindex, 1); 1093 /* 1094 * next object 1095 */ 1096 backing_object = tobject->backing_object; 1097 if (backing_object == NULL) 1098 goto unlock_tobject; 1099 VM_OBJECT_LOCK(backing_object); 1100 tpindex += OFF_TO_IDX(tobject->backing_object_offset); 1101 if (tobject != object) 1102 VM_OBJECT_UNLOCK(tobject); 1103 tobject = backing_object; 1104 goto shadowlookup; 1105 } 1106 /* 1107 * If the page is busy or not in a normal active state, 1108 * we skip it. If the page is not managed there are no 1109 * page queues to mess with. Things can break if we mess 1110 * with pages in any of the below states. 1111 */ 1112 vm_page_lock_queues(); 1113 if (m->hold_count || 1114 m->wire_count || 1115 (m->flags & PG_UNMANAGED) || 1116 m->valid != VM_PAGE_BITS_ALL) { 1117 vm_page_unlock_queues(); 1118 goto unlock_tobject; 1119 } 1120 if ((m->flags & PG_BUSY) || m->busy) { 1121 vm_page_flag_set(m, PG_WANTED | PG_REFERENCED); 1122 if (object != tobject) 1123 VM_OBJECT_UNLOCK(object); 1124 VM_OBJECT_UNLOCK(tobject); 1125 msleep(m, &vm_page_queue_mtx, PDROP | PVM, "madvpo", 0); 1126 VM_OBJECT_LOCK(object); 1127 goto relookup; 1128 } 1129 if (advise == MADV_WILLNEED) { 1130 vm_page_activate(m); 1131 } else if (advise == MADV_DONTNEED) { 1132 vm_page_dontneed(m); 1133 } else if (advise == MADV_FREE) { 1134 /* 1135 * Mark the page clean. This will allow the page 1136 * to be freed up by the system. However, such pages 1137 * are often reused quickly by malloc()/free() 1138 * so we do not do anything that would cause 1139 * a page fault if we can help it. 1140 * 1141 * Specifically, we do not try to actually free 1142 * the page now nor do we try to put it in the 1143 * cache (which would cause a page fault on reuse). 1144 * 1145 * But we do make the page is freeable as we 1146 * can without actually taking the step of unmapping 1147 * it. 1148 */ 1149 pmap_clear_modify(m); 1150 m->dirty = 0; 1151 m->act_count = 0; 1152 vm_page_dontneed(m); 1153 } 1154 vm_page_unlock_queues(); 1155 if (advise == MADV_FREE && tobject->type == OBJT_SWAP) 1156 swap_pager_freespace(tobject, tpindex, 1); 1157 unlock_tobject: 1158 if (tobject != object) 1159 VM_OBJECT_UNLOCK(tobject); 1160 } 1161 VM_OBJECT_UNLOCK(object); 1162 } 1163 1164 /* 1165 * vm_object_shadow: 1166 * 1167 * Create a new object which is backed by the 1168 * specified existing object range. The source 1169 * object reference is deallocated. 1170 * 1171 * The new object and offset into that object 1172 * are returned in the source parameters. 1173 */ 1174 void 1175 vm_object_shadow( 1176 vm_object_t *object, /* IN/OUT */ 1177 vm_ooffset_t *offset, /* IN/OUT */ 1178 vm_size_t length) 1179 { 1180 vm_object_t source; 1181 vm_object_t result; 1182 1183 source = *object; 1184 1185 /* 1186 * Don't create the new object if the old object isn't shared. 1187 */ 1188 if (source != NULL) { 1189 VM_OBJECT_LOCK(source); 1190 if (source->ref_count == 1 && 1191 source->handle == NULL && 1192 (source->type == OBJT_DEFAULT || 1193 source->type == OBJT_SWAP)) { 1194 VM_OBJECT_UNLOCK(source); 1195 return; 1196 } 1197 VM_OBJECT_UNLOCK(source); 1198 } 1199 1200 /* 1201 * Allocate a new object with the given length. 1202 */ 1203 result = vm_object_allocate(OBJT_DEFAULT, length); 1204 1205 /* 1206 * The new object shadows the source object, adding a reference to it. 1207 * Our caller changes his reference to point to the new object, 1208 * removing a reference to the source object. Net result: no change 1209 * of reference count. 1210 * 1211 * Try to optimize the result object's page color when shadowing 1212 * in order to maintain page coloring consistency in the combined 1213 * shadowed object. 1214 */ 1215 result->backing_object = source; 1216 /* 1217 * Store the offset into the source object, and fix up the offset into 1218 * the new object. 1219 */ 1220 result->backing_object_offset = *offset; 1221 if (source != NULL) { 1222 VM_OBJECT_LOCK(source); 1223 LIST_INSERT_HEAD(&source->shadow_head, result, shadow_list); 1224 source->shadow_count++; 1225 source->generation++; 1226 if (length < source->size) 1227 length = source->size; 1228 if (length > PQ_L2_SIZE / 3 + PQ_PRIME1 || 1229 source->generation > 1) 1230 length = PQ_L2_SIZE / 3 + PQ_PRIME1; 1231 result->pg_color = (source->pg_color + 1232 length * source->generation) & PQ_L2_MASK; 1233 VM_OBJECT_UNLOCK(source); 1234 next_index = (result->pg_color + PQ_L2_SIZE / 3 + PQ_PRIME1) & 1235 PQ_L2_MASK; 1236 } 1237 1238 1239 /* 1240 * Return the new things 1241 */ 1242 *offset = 0; 1243 *object = result; 1244 } 1245 1246 /* 1247 * vm_object_split: 1248 * 1249 * Split the pages in a map entry into a new object. This affords 1250 * easier removal of unused pages, and keeps object inheritance from 1251 * being a negative impact on memory usage. 1252 */ 1253 void 1254 vm_object_split(vm_map_entry_t entry) 1255 { 1256 vm_page_t m; 1257 vm_object_t orig_object, new_object, source; 1258 vm_pindex_t offidxstart, offidxend; 1259 vm_size_t idx, size; 1260 1261 orig_object = entry->object.vm_object; 1262 if (orig_object->type != OBJT_DEFAULT && orig_object->type != OBJT_SWAP) 1263 return; 1264 if (orig_object->ref_count <= 1) 1265 return; 1266 VM_OBJECT_UNLOCK(orig_object); 1267 1268 offidxstart = OFF_TO_IDX(entry->offset); 1269 offidxend = offidxstart + OFF_TO_IDX(entry->end - entry->start); 1270 size = offidxend - offidxstart; 1271 1272 /* 1273 * If swap_pager_copy() is later called, it will convert new_object 1274 * into a swap object. 1275 */ 1276 new_object = vm_object_allocate(OBJT_DEFAULT, size); 1277 1278 VM_OBJECT_LOCK(new_object); 1279 VM_OBJECT_LOCK(orig_object); 1280 source = orig_object->backing_object; 1281 if (source != NULL) { 1282 VM_OBJECT_LOCK(source); 1283 LIST_INSERT_HEAD(&source->shadow_head, 1284 new_object, shadow_list); 1285 source->shadow_count++; 1286 source->generation++; 1287 vm_object_reference_locked(source); /* for new_object */ 1288 vm_object_clear_flag(source, OBJ_ONEMAPPING); 1289 VM_OBJECT_UNLOCK(source); 1290 new_object->backing_object_offset = 1291 orig_object->backing_object_offset + entry->offset; 1292 new_object->backing_object = source; 1293 } 1294 vm_page_lock_queues(); 1295 for (idx = 0; idx < size; idx++) { 1296 retry: 1297 m = vm_page_lookup(orig_object, offidxstart + idx); 1298 if (m == NULL) 1299 continue; 1300 1301 /* 1302 * We must wait for pending I/O to complete before we can 1303 * rename the page. 1304 * 1305 * We do not have to VM_PROT_NONE the page as mappings should 1306 * not be changed by this operation. 1307 */ 1308 if ((m->flags & PG_BUSY) || m->busy) { 1309 vm_page_flag_set(m, PG_WANTED | PG_REFERENCED); 1310 VM_OBJECT_UNLOCK(orig_object); 1311 VM_OBJECT_UNLOCK(new_object); 1312 msleep(m, &vm_page_queue_mtx, PDROP | PVM, "spltwt", 0); 1313 VM_OBJECT_LOCK(new_object); 1314 VM_OBJECT_LOCK(orig_object); 1315 vm_page_lock_queues(); 1316 goto retry; 1317 } 1318 vm_page_rename(m, new_object, idx); 1319 /* page automatically made dirty by rename and cache handled */ 1320 vm_page_busy(m); 1321 } 1322 vm_page_unlock_queues(); 1323 if (orig_object->type == OBJT_SWAP) { 1324 /* 1325 * swap_pager_copy() can sleep, in which case the orig_object's 1326 * and new_object's locks are released and reacquired. 1327 */ 1328 swap_pager_copy(orig_object, new_object, offidxstart, 0); 1329 } 1330 VM_OBJECT_UNLOCK(orig_object); 1331 vm_page_lock_queues(); 1332 TAILQ_FOREACH(m, &new_object->memq, listq) 1333 vm_page_wakeup(m); 1334 vm_page_unlock_queues(); 1335 VM_OBJECT_UNLOCK(new_object); 1336 entry->object.vm_object = new_object; 1337 entry->offset = 0LL; 1338 vm_object_deallocate(orig_object); 1339 VM_OBJECT_LOCK(new_object); 1340 } 1341 1342 #define OBSC_TEST_ALL_SHADOWED 0x0001 1343 #define OBSC_COLLAPSE_NOWAIT 0x0002 1344 #define OBSC_COLLAPSE_WAIT 0x0004 1345 1346 static int 1347 vm_object_backing_scan(vm_object_t object, int op) 1348 { 1349 int r = 1; 1350 vm_page_t p; 1351 vm_object_t backing_object; 1352 vm_pindex_t backing_offset_index; 1353 1354 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1355 VM_OBJECT_LOCK_ASSERT(object->backing_object, MA_OWNED); 1356 1357 backing_object = object->backing_object; 1358 backing_offset_index = OFF_TO_IDX(object->backing_object_offset); 1359 1360 /* 1361 * Initial conditions 1362 */ 1363 if (op & OBSC_TEST_ALL_SHADOWED) { 1364 /* 1365 * We do not want to have to test for the existence of 1366 * swap pages in the backing object. XXX but with the 1367 * new swapper this would be pretty easy to do. 1368 * 1369 * XXX what about anonymous MAP_SHARED memory that hasn't 1370 * been ZFOD faulted yet? If we do not test for this, the 1371 * shadow test may succeed! XXX 1372 */ 1373 if (backing_object->type != OBJT_DEFAULT) { 1374 return (0); 1375 } 1376 } 1377 if (op & OBSC_COLLAPSE_WAIT) { 1378 vm_object_set_flag(backing_object, OBJ_DEAD); 1379 } 1380 1381 /* 1382 * Our scan 1383 */ 1384 p = TAILQ_FIRST(&backing_object->memq); 1385 while (p) { 1386 vm_page_t next = TAILQ_NEXT(p, listq); 1387 vm_pindex_t new_pindex = p->pindex - backing_offset_index; 1388 1389 if (op & OBSC_TEST_ALL_SHADOWED) { 1390 vm_page_t pp; 1391 1392 /* 1393 * Ignore pages outside the parent object's range 1394 * and outside the parent object's mapping of the 1395 * backing object. 1396 * 1397 * note that we do not busy the backing object's 1398 * page. 1399 */ 1400 if ( 1401 p->pindex < backing_offset_index || 1402 new_pindex >= object->size 1403 ) { 1404 p = next; 1405 continue; 1406 } 1407 1408 /* 1409 * See if the parent has the page or if the parent's 1410 * object pager has the page. If the parent has the 1411 * page but the page is not valid, the parent's 1412 * object pager must have the page. 1413 * 1414 * If this fails, the parent does not completely shadow 1415 * the object and we might as well give up now. 1416 */ 1417 1418 pp = vm_page_lookup(object, new_pindex); 1419 if ( 1420 (pp == NULL || pp->valid == 0) && 1421 !vm_pager_has_page(object, new_pindex, NULL, NULL) 1422 ) { 1423 r = 0; 1424 break; 1425 } 1426 } 1427 1428 /* 1429 * Check for busy page 1430 */ 1431 if (op & (OBSC_COLLAPSE_WAIT | OBSC_COLLAPSE_NOWAIT)) { 1432 vm_page_t pp; 1433 1434 vm_page_lock_queues(); 1435 if (op & OBSC_COLLAPSE_NOWAIT) { 1436 if ((p->flags & PG_BUSY) || 1437 !p->valid || 1438 p->hold_count || 1439 p->wire_count || 1440 p->busy) { 1441 vm_page_unlock_queues(); 1442 p = next; 1443 continue; 1444 } 1445 } else if (op & OBSC_COLLAPSE_WAIT) { 1446 if ((p->flags & PG_BUSY) || p->busy) { 1447 vm_page_flag_set(p, 1448 PG_WANTED | PG_REFERENCED); 1449 VM_OBJECT_UNLOCK(backing_object); 1450 VM_OBJECT_UNLOCK(object); 1451 msleep(p, &vm_page_queue_mtx, 1452 PDROP | PVM, "vmocol", 0); 1453 VM_OBJECT_LOCK(object); 1454 VM_OBJECT_LOCK(backing_object); 1455 /* 1456 * If we slept, anything could have 1457 * happened. Since the object is 1458 * marked dead, the backing offset 1459 * should not have changed so we 1460 * just restart our scan. 1461 */ 1462 p = TAILQ_FIRST(&backing_object->memq); 1463 continue; 1464 } 1465 } 1466 vm_page_unlock_queues(); 1467 1468 KASSERT( 1469 p->object == backing_object, 1470 ("vm_object_backing_scan: object mismatch") 1471 ); 1472 1473 /* 1474 * Destroy any associated swap 1475 */ 1476 if (backing_object->type == OBJT_SWAP) { 1477 swap_pager_freespace( 1478 backing_object, 1479 p->pindex, 1480 1 1481 ); 1482 } 1483 1484 if ( 1485 p->pindex < backing_offset_index || 1486 new_pindex >= object->size 1487 ) { 1488 /* 1489 * Page is out of the parent object's range, we 1490 * can simply destroy it. 1491 */ 1492 vm_page_lock_queues(); 1493 pmap_remove_all(p); 1494 vm_page_free(p); 1495 vm_page_unlock_queues(); 1496 p = next; 1497 continue; 1498 } 1499 1500 pp = vm_page_lookup(object, new_pindex); 1501 if ( 1502 pp != NULL || 1503 vm_pager_has_page(object, new_pindex, NULL, NULL) 1504 ) { 1505 /* 1506 * page already exists in parent OR swap exists 1507 * for this location in the parent. Destroy 1508 * the original page from the backing object. 1509 * 1510 * Leave the parent's page alone 1511 */ 1512 vm_page_lock_queues(); 1513 pmap_remove_all(p); 1514 vm_page_free(p); 1515 vm_page_unlock_queues(); 1516 p = next; 1517 continue; 1518 } 1519 1520 /* 1521 * Page does not exist in parent, rename the 1522 * page from the backing object to the main object. 1523 * 1524 * If the page was mapped to a process, it can remain 1525 * mapped through the rename. 1526 */ 1527 vm_page_lock_queues(); 1528 vm_page_rename(p, object, new_pindex); 1529 vm_page_unlock_queues(); 1530 /* page automatically made dirty by rename */ 1531 } 1532 p = next; 1533 } 1534 return (r); 1535 } 1536 1537 1538 /* 1539 * this version of collapse allows the operation to occur earlier and 1540 * when paging_in_progress is true for an object... This is not a complete 1541 * operation, but should plug 99.9% of the rest of the leaks. 1542 */ 1543 static void 1544 vm_object_qcollapse(vm_object_t object) 1545 { 1546 vm_object_t backing_object = object->backing_object; 1547 1548 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1549 VM_OBJECT_LOCK_ASSERT(backing_object, MA_OWNED); 1550 1551 if (backing_object->ref_count != 1) 1552 return; 1553 1554 vm_object_backing_scan(object, OBSC_COLLAPSE_NOWAIT); 1555 } 1556 1557 /* 1558 * vm_object_collapse: 1559 * 1560 * Collapse an object with the object backing it. 1561 * Pages in the backing object are moved into the 1562 * parent, and the backing object is deallocated. 1563 */ 1564 void 1565 vm_object_collapse(vm_object_t object) 1566 { 1567 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1568 1569 while (TRUE) { 1570 vm_object_t backing_object; 1571 1572 /* 1573 * Verify that the conditions are right for collapse: 1574 * 1575 * The object exists and the backing object exists. 1576 */ 1577 if ((backing_object = object->backing_object) == NULL) 1578 break; 1579 1580 /* 1581 * we check the backing object first, because it is most likely 1582 * not collapsable. 1583 */ 1584 VM_OBJECT_LOCK(backing_object); 1585 if (backing_object->handle != NULL || 1586 (backing_object->type != OBJT_DEFAULT && 1587 backing_object->type != OBJT_SWAP) || 1588 (backing_object->flags & OBJ_DEAD) || 1589 object->handle != NULL || 1590 (object->type != OBJT_DEFAULT && 1591 object->type != OBJT_SWAP) || 1592 (object->flags & OBJ_DEAD)) { 1593 VM_OBJECT_UNLOCK(backing_object); 1594 break; 1595 } 1596 1597 if ( 1598 object->paging_in_progress != 0 || 1599 backing_object->paging_in_progress != 0 1600 ) { 1601 vm_object_qcollapse(object); 1602 VM_OBJECT_UNLOCK(backing_object); 1603 break; 1604 } 1605 /* 1606 * We know that we can either collapse the backing object (if 1607 * the parent is the only reference to it) or (perhaps) have 1608 * the parent bypass the object if the parent happens to shadow 1609 * all the resident pages in the entire backing object. 1610 * 1611 * This is ignoring pager-backed pages such as swap pages. 1612 * vm_object_backing_scan fails the shadowing test in this 1613 * case. 1614 */ 1615 if (backing_object->ref_count == 1) { 1616 /* 1617 * If there is exactly one reference to the backing 1618 * object, we can collapse it into the parent. 1619 */ 1620 vm_object_backing_scan(object, OBSC_COLLAPSE_WAIT); 1621 1622 /* 1623 * Move the pager from backing_object to object. 1624 */ 1625 if (backing_object->type == OBJT_SWAP) { 1626 /* 1627 * swap_pager_copy() can sleep, in which case 1628 * the backing_object's and object's locks are 1629 * released and reacquired. 1630 */ 1631 swap_pager_copy( 1632 backing_object, 1633 object, 1634 OFF_TO_IDX(object->backing_object_offset), TRUE); 1635 } 1636 /* 1637 * Object now shadows whatever backing_object did. 1638 * Note that the reference to 1639 * backing_object->backing_object moves from within 1640 * backing_object to within object. 1641 */ 1642 LIST_REMOVE(object, shadow_list); 1643 backing_object->shadow_count--; 1644 backing_object->generation++; 1645 if (backing_object->backing_object) { 1646 VM_OBJECT_LOCK(backing_object->backing_object); 1647 LIST_REMOVE(backing_object, shadow_list); 1648 LIST_INSERT_HEAD( 1649 &backing_object->backing_object->shadow_head, 1650 object, shadow_list); 1651 /* 1652 * The shadow_count has not changed. 1653 */ 1654 backing_object->backing_object->generation++; 1655 VM_OBJECT_UNLOCK(backing_object->backing_object); 1656 } 1657 object->backing_object = backing_object->backing_object; 1658 object->backing_object_offset += 1659 backing_object->backing_object_offset; 1660 1661 /* 1662 * Discard backing_object. 1663 * 1664 * Since the backing object has no pages, no pager left, 1665 * and no object references within it, all that is 1666 * necessary is to dispose of it. 1667 */ 1668 KASSERT(backing_object->ref_count == 1, ("backing_object %p was somehow re-referenced during collapse!", backing_object)); 1669 VM_OBJECT_UNLOCK(backing_object); 1670 1671 mtx_lock(&vm_object_list_mtx); 1672 TAILQ_REMOVE( 1673 &vm_object_list, 1674 backing_object, 1675 object_list 1676 ); 1677 mtx_unlock(&vm_object_list_mtx); 1678 1679 uma_zfree(obj_zone, backing_object); 1680 1681 object_collapses++; 1682 } else { 1683 vm_object_t new_backing_object; 1684 1685 /* 1686 * If we do not entirely shadow the backing object, 1687 * there is nothing we can do so we give up. 1688 */ 1689 if (vm_object_backing_scan(object, OBSC_TEST_ALL_SHADOWED) == 0) { 1690 VM_OBJECT_UNLOCK(backing_object); 1691 break; 1692 } 1693 1694 /* 1695 * Make the parent shadow the next object in the 1696 * chain. Deallocating backing_object will not remove 1697 * it, since its reference count is at least 2. 1698 */ 1699 LIST_REMOVE(object, shadow_list); 1700 backing_object->shadow_count--; 1701 backing_object->generation++; 1702 1703 new_backing_object = backing_object->backing_object; 1704 if ((object->backing_object = new_backing_object) != NULL) { 1705 VM_OBJECT_LOCK(new_backing_object); 1706 LIST_INSERT_HEAD( 1707 &new_backing_object->shadow_head, 1708 object, 1709 shadow_list 1710 ); 1711 new_backing_object->shadow_count++; 1712 new_backing_object->generation++; 1713 vm_object_reference_locked(new_backing_object); 1714 VM_OBJECT_UNLOCK(new_backing_object); 1715 object->backing_object_offset += 1716 backing_object->backing_object_offset; 1717 } 1718 1719 /* 1720 * Drop the reference count on backing_object. Since 1721 * its ref_count was at least 2, it will not vanish. 1722 */ 1723 backing_object->ref_count--; 1724 VM_OBJECT_UNLOCK(backing_object); 1725 object_bypasses++; 1726 } 1727 1728 /* 1729 * Try again with this object's new backing object. 1730 */ 1731 } 1732 } 1733 1734 /* 1735 * vm_object_page_remove: 1736 * 1737 * Removes all physical pages in the given range from the 1738 * object's list of pages. If the range's end is zero, all 1739 * physical pages from the range's start to the end of the object 1740 * are deleted. 1741 * 1742 * The object must be locked. 1743 */ 1744 void 1745 vm_object_page_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end, 1746 boolean_t clean_only) 1747 { 1748 vm_page_t p, next; 1749 1750 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1751 if (object->resident_page_count == 0) 1752 return; 1753 1754 /* 1755 * Since physically-backed objects do not use managed pages, we can't 1756 * remove pages from the object (we must instead remove the page 1757 * references, and then destroy the object). 1758 */ 1759 KASSERT(object->type != OBJT_PHYS, 1760 ("attempt to remove pages from a physical object")); 1761 1762 vm_object_pip_add(object, 1); 1763 again: 1764 vm_page_lock_queues(); 1765 if ((p = TAILQ_FIRST(&object->memq)) != NULL) { 1766 if (p->pindex < start) { 1767 p = vm_page_splay(start, object->root); 1768 if ((object->root = p)->pindex < start) 1769 p = TAILQ_NEXT(p, listq); 1770 } 1771 } 1772 /* 1773 * Assert: the variable p is either (1) the page with the 1774 * least pindex greater than or equal to the parameter pindex 1775 * or (2) NULL. 1776 */ 1777 for (; 1778 p != NULL && (p->pindex < end || end == 0); 1779 p = next) { 1780 next = TAILQ_NEXT(p, listq); 1781 1782 if (p->wire_count != 0) { 1783 pmap_remove_all(p); 1784 if (!clean_only) 1785 p->valid = 0; 1786 continue; 1787 } 1788 if (vm_page_sleep_if_busy(p, TRUE, "vmopar")) 1789 goto again; 1790 if (clean_only && p->valid) { 1791 pmap_page_protect(p, VM_PROT_READ | VM_PROT_EXECUTE); 1792 if (p->valid & p->dirty) 1793 continue; 1794 } 1795 pmap_remove_all(p); 1796 vm_page_free(p); 1797 } 1798 vm_page_unlock_queues(); 1799 vm_object_pip_wakeup(object); 1800 } 1801 1802 /* 1803 * Routine: vm_object_coalesce 1804 * Function: Coalesces two objects backing up adjoining 1805 * regions of memory into a single object. 1806 * 1807 * returns TRUE if objects were combined. 1808 * 1809 * NOTE: Only works at the moment if the second object is NULL - 1810 * if it's not, which object do we lock first? 1811 * 1812 * Parameters: 1813 * prev_object First object to coalesce 1814 * prev_offset Offset into prev_object 1815 * prev_size Size of reference to prev_object 1816 * next_size Size of reference to the second object 1817 * 1818 * Conditions: 1819 * The object must *not* be locked. 1820 */ 1821 boolean_t 1822 vm_object_coalesce(vm_object_t prev_object, vm_ooffset_t prev_offset, 1823 vm_size_t prev_size, vm_size_t next_size) 1824 { 1825 vm_pindex_t next_pindex; 1826 1827 if (prev_object == NULL) 1828 return (TRUE); 1829 VM_OBJECT_LOCK(prev_object); 1830 if (prev_object->type != OBJT_DEFAULT && 1831 prev_object->type != OBJT_SWAP) { 1832 VM_OBJECT_UNLOCK(prev_object); 1833 return (FALSE); 1834 } 1835 1836 /* 1837 * Try to collapse the object first 1838 */ 1839 vm_object_collapse(prev_object); 1840 1841 /* 1842 * Can't coalesce if: . more than one reference . paged out . shadows 1843 * another object . has a copy elsewhere (any of which mean that the 1844 * pages not mapped to prev_entry may be in use anyway) 1845 */ 1846 if (prev_object->backing_object != NULL) { 1847 VM_OBJECT_UNLOCK(prev_object); 1848 return (FALSE); 1849 } 1850 1851 prev_size >>= PAGE_SHIFT; 1852 next_size >>= PAGE_SHIFT; 1853 next_pindex = OFF_TO_IDX(prev_offset) + prev_size; 1854 1855 if ((prev_object->ref_count > 1) && 1856 (prev_object->size != next_pindex)) { 1857 VM_OBJECT_UNLOCK(prev_object); 1858 return (FALSE); 1859 } 1860 1861 /* 1862 * Remove any pages that may still be in the object from a previous 1863 * deallocation. 1864 */ 1865 if (next_pindex < prev_object->size) { 1866 vm_object_page_remove(prev_object, 1867 next_pindex, 1868 next_pindex + next_size, FALSE); 1869 if (prev_object->type == OBJT_SWAP) 1870 swap_pager_freespace(prev_object, 1871 next_pindex, next_size); 1872 } 1873 1874 /* 1875 * Extend the object if necessary. 1876 */ 1877 if (next_pindex + next_size > prev_object->size) 1878 prev_object->size = next_pindex + next_size; 1879 1880 VM_OBJECT_UNLOCK(prev_object); 1881 return (TRUE); 1882 } 1883 1884 void 1885 vm_object_set_writeable_dirty(vm_object_t object) 1886 { 1887 struct vnode *vp; 1888 1889 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1890 vm_object_set_flag(object, OBJ_WRITEABLE|OBJ_MIGHTBEDIRTY); 1891 if (object->type == OBJT_VNODE && 1892 (vp = (struct vnode *)object->handle) != NULL) { 1893 VI_LOCK(vp); 1894 if ((vp->v_iflag & VI_OBJDIRTY) == 0) 1895 vp->v_iflag |= VI_OBJDIRTY; 1896 VI_UNLOCK(vp); 1897 } 1898 } 1899 1900 #include "opt_ddb.h" 1901 #ifdef DDB 1902 #include <sys/kernel.h> 1903 1904 #include <sys/cons.h> 1905 1906 #include <ddb/ddb.h> 1907 1908 static int 1909 _vm_object_in_map(vm_map_t map, vm_object_t object, vm_map_entry_t entry) 1910 { 1911 vm_map_t tmpm; 1912 vm_map_entry_t tmpe; 1913 vm_object_t obj; 1914 int entcount; 1915 1916 if (map == 0) 1917 return 0; 1918 1919 if (entry == 0) { 1920 tmpe = map->header.next; 1921 entcount = map->nentries; 1922 while (entcount-- && (tmpe != &map->header)) { 1923 if (_vm_object_in_map(map, object, tmpe)) { 1924 return 1; 1925 } 1926 tmpe = tmpe->next; 1927 } 1928 } else if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) { 1929 tmpm = entry->object.sub_map; 1930 tmpe = tmpm->header.next; 1931 entcount = tmpm->nentries; 1932 while (entcount-- && tmpe != &tmpm->header) { 1933 if (_vm_object_in_map(tmpm, object, tmpe)) { 1934 return 1; 1935 } 1936 tmpe = tmpe->next; 1937 } 1938 } else if ((obj = entry->object.vm_object) != NULL) { 1939 for (; obj; obj = obj->backing_object) 1940 if (obj == object) { 1941 return 1; 1942 } 1943 } 1944 return 0; 1945 } 1946 1947 static int 1948 vm_object_in_map(vm_object_t object) 1949 { 1950 struct proc *p; 1951 1952 /* sx_slock(&allproc_lock); */ 1953 LIST_FOREACH(p, &allproc, p_list) { 1954 if (!p->p_vmspace /* || (p->p_flag & (P_SYSTEM|P_WEXIT)) */) 1955 continue; 1956 if (_vm_object_in_map(&p->p_vmspace->vm_map, object, 0)) { 1957 /* sx_sunlock(&allproc_lock); */ 1958 return 1; 1959 } 1960 } 1961 /* sx_sunlock(&allproc_lock); */ 1962 if (_vm_object_in_map(kernel_map, object, 0)) 1963 return 1; 1964 if (_vm_object_in_map(kmem_map, object, 0)) 1965 return 1; 1966 if (_vm_object_in_map(pager_map, object, 0)) 1967 return 1; 1968 if (_vm_object_in_map(buffer_map, object, 0)) 1969 return 1; 1970 return 0; 1971 } 1972 1973 DB_SHOW_COMMAND(vmochk, vm_object_check) 1974 { 1975 vm_object_t object; 1976 1977 /* 1978 * make sure that internal objs are in a map somewhere 1979 * and none have zero ref counts. 1980 */ 1981 TAILQ_FOREACH(object, &vm_object_list, object_list) { 1982 if (object->handle == NULL && 1983 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) { 1984 if (object->ref_count == 0) { 1985 db_printf("vmochk: internal obj has zero ref count: %ld\n", 1986 (long)object->size); 1987 } 1988 if (!vm_object_in_map(object)) { 1989 db_printf( 1990 "vmochk: internal obj is not in a map: " 1991 "ref: %d, size: %lu: 0x%lx, backing_object: %p\n", 1992 object->ref_count, (u_long)object->size, 1993 (u_long)object->size, 1994 (void *)object->backing_object); 1995 } 1996 } 1997 } 1998 } 1999 2000 /* 2001 * vm_object_print: [ debug ] 2002 */ 2003 DB_SHOW_COMMAND(object, vm_object_print_static) 2004 { 2005 /* XXX convert args. */ 2006 vm_object_t object = (vm_object_t)addr; 2007 boolean_t full = have_addr; 2008 2009 vm_page_t p; 2010 2011 /* XXX count is an (unused) arg. Avoid shadowing it. */ 2012 #define count was_count 2013 2014 int count; 2015 2016 if (object == NULL) 2017 return; 2018 2019 db_iprintf( 2020 "Object %p: type=%d, size=0x%jx, res=%d, ref=%d, flags=0x%x\n", 2021 object, (int)object->type, (uintmax_t)object->size, 2022 object->resident_page_count, object->ref_count, object->flags); 2023 db_iprintf(" sref=%d, backing_object(%d)=(%p)+0x%jx\n", 2024 object->shadow_count, 2025 object->backing_object ? object->backing_object->ref_count : 0, 2026 object->backing_object, (uintmax_t)object->backing_object_offset); 2027 2028 if (!full) 2029 return; 2030 2031 db_indent += 2; 2032 count = 0; 2033 TAILQ_FOREACH(p, &object->memq, listq) { 2034 if (count == 0) 2035 db_iprintf("memory:="); 2036 else if (count == 6) { 2037 db_printf("\n"); 2038 db_iprintf(" ..."); 2039 count = 0; 2040 } else 2041 db_printf(","); 2042 count++; 2043 2044 db_printf("(off=0x%jx,page=0x%jx)", 2045 (uintmax_t)p->pindex, (uintmax_t)VM_PAGE_TO_PHYS(p)); 2046 } 2047 if (count != 0) 2048 db_printf("\n"); 2049 db_indent -= 2; 2050 } 2051 2052 /* XXX. */ 2053 #undef count 2054 2055 /* XXX need this non-static entry for calling from vm_map_print. */ 2056 void 2057 vm_object_print( 2058 /* db_expr_t */ long addr, 2059 boolean_t have_addr, 2060 /* db_expr_t */ long count, 2061 char *modif) 2062 { 2063 vm_object_print_static(addr, have_addr, count, modif); 2064 } 2065 2066 DB_SHOW_COMMAND(vmopag, vm_object_print_pages) 2067 { 2068 vm_object_t object; 2069 int nl = 0; 2070 int c; 2071 2072 TAILQ_FOREACH(object, &vm_object_list, object_list) { 2073 vm_pindex_t idx, fidx; 2074 vm_pindex_t osize; 2075 vm_paddr_t pa = -1, padiff; 2076 int rcount; 2077 vm_page_t m; 2078 2079 db_printf("new object: %p\n", (void *)object); 2080 if (nl > 18) { 2081 c = cngetc(); 2082 if (c != ' ') 2083 return; 2084 nl = 0; 2085 } 2086 nl++; 2087 rcount = 0; 2088 fidx = 0; 2089 osize = object->size; 2090 if (osize > 128) 2091 osize = 128; 2092 for (idx = 0; idx < osize; idx++) { 2093 m = vm_page_lookup(object, idx); 2094 if (m == NULL) { 2095 if (rcount) { 2096 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2097 (long)fidx, rcount, (long)pa); 2098 if (nl > 18) { 2099 c = cngetc(); 2100 if (c != ' ') 2101 return; 2102 nl = 0; 2103 } 2104 nl++; 2105 rcount = 0; 2106 } 2107 continue; 2108 } 2109 2110 2111 if (rcount && 2112 (VM_PAGE_TO_PHYS(m) == pa + rcount * PAGE_SIZE)) { 2113 ++rcount; 2114 continue; 2115 } 2116 if (rcount) { 2117 padiff = pa + rcount * PAGE_SIZE - VM_PAGE_TO_PHYS(m); 2118 padiff >>= PAGE_SHIFT; 2119 padiff &= PQ_L2_MASK; 2120 if (padiff == 0) { 2121 pa = VM_PAGE_TO_PHYS(m) - rcount * PAGE_SIZE; 2122 ++rcount; 2123 continue; 2124 } 2125 db_printf(" index(%ld)run(%d)pa(0x%lx)", 2126 (long)fidx, rcount, (long)pa); 2127 db_printf("pd(%ld)\n", (long)padiff); 2128 if (nl > 18) { 2129 c = cngetc(); 2130 if (c != ' ') 2131 return; 2132 nl = 0; 2133 } 2134 nl++; 2135 } 2136 fidx = idx; 2137 pa = VM_PAGE_TO_PHYS(m); 2138 rcount = 1; 2139 } 2140 if (rcount) { 2141 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2142 (long)fidx, rcount, (long)pa); 2143 if (nl > 18) { 2144 c = cngetc(); 2145 if (c != ' ') 2146 return; 2147 nl = 0; 2148 } 2149 nl++; 2150 } 2151 } 2152 } 2153 #endif /* DDB */ 2154