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_NODE(_vm_stats, OID_AUTO, object, CTLFLAG_RD, 0, "VM object stats"); 148 149 static long object_collapses; 150 SYSCTL_LONG(_vm_stats_object, OID_AUTO, collapses, CTLFLAG_RD, 151 &object_collapses, 0, "VM object collapses"); 152 153 static long object_bypasses; 154 SYSCTL_LONG(_vm_stats_object, OID_AUTO, bypasses, CTLFLAG_RD, 155 &object_bypasses, 0, "VM object bypasses"); 156 157 /* 158 * next_index determines the page color that is assigned to the next 159 * allocated object. Accesses to next_index are not synchronized 160 * because the effects of two or more object allocations using 161 * next_index simultaneously are inconsequential. At any given time, 162 * numerous objects have the same page color. 163 */ 164 static int next_index; 165 166 static uma_zone_t obj_zone; 167 168 static int vm_object_zinit(void *mem, int size, int flags); 169 170 #ifdef INVARIANTS 171 static void vm_object_zdtor(void *mem, int size, void *arg); 172 173 static void 174 vm_object_zdtor(void *mem, int size, void *arg) 175 { 176 vm_object_t object; 177 178 object = (vm_object_t)mem; 179 KASSERT(TAILQ_EMPTY(&object->memq), 180 ("object %p has resident pages", 181 object)); 182 KASSERT(object->paging_in_progress == 0, 183 ("object %p paging_in_progress = %d", 184 object, object->paging_in_progress)); 185 KASSERT(object->resident_page_count == 0, 186 ("object %p resident_page_count = %d", 187 object, object->resident_page_count)); 188 KASSERT(object->shadow_count == 0, 189 ("object %p shadow_count = %d", 190 object, object->shadow_count)); 191 } 192 #endif 193 194 static int 195 vm_object_zinit(void *mem, int size, int flags) 196 { 197 vm_object_t object; 198 199 object = (vm_object_t)mem; 200 bzero(&object->mtx, sizeof(object->mtx)); 201 VM_OBJECT_LOCK_INIT(object, "standard object"); 202 203 /* These are true for any object that has been freed */ 204 object->paging_in_progress = 0; 205 object->resident_page_count = 0; 206 object->shadow_count = 0; 207 return (0); 208 } 209 210 void 211 _vm_object_allocate(objtype_t type, vm_pindex_t size, vm_object_t object) 212 { 213 int incr; 214 215 TAILQ_INIT(&object->memq); 216 LIST_INIT(&object->shadow_head); 217 218 object->root = NULL; 219 object->type = type; 220 object->size = size; 221 object->generation = 1; 222 object->ref_count = 1; 223 object->flags = 0; 224 if ((object->type == OBJT_DEFAULT) || (object->type == OBJT_SWAP)) 225 object->flags = OBJ_ONEMAPPING; 226 incr = PQ_MAXLENGTH; 227 if (size <= incr) 228 incr = size; 229 object->pg_color = next_index; 230 next_index = (object->pg_color + incr) & PQ_COLORMASK; 231 object->handle = NULL; 232 object->backing_object = NULL; 233 object->backing_object_offset = (vm_ooffset_t) 0; 234 235 mtx_lock(&vm_object_list_mtx); 236 TAILQ_INSERT_TAIL(&vm_object_list, object, object_list); 237 mtx_unlock(&vm_object_list_mtx); 238 } 239 240 /* 241 * vm_object_init: 242 * 243 * Initialize the VM objects module. 244 */ 245 void 246 vm_object_init(void) 247 { 248 TAILQ_INIT(&vm_object_list); 249 mtx_init(&vm_object_list_mtx, "vm object_list", NULL, MTX_DEF); 250 251 VM_OBJECT_LOCK_INIT(&kernel_object_store, "kernel object"); 252 _vm_object_allocate(OBJT_PHYS, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS), 253 kernel_object); 254 255 VM_OBJECT_LOCK_INIT(&kmem_object_store, "kmem object"); 256 _vm_object_allocate(OBJT_PHYS, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS), 257 kmem_object); 258 259 /* 260 * The lock portion of struct vm_object must be type stable due 261 * to vm_pageout_fallback_object_lock locking a vm object 262 * without holding any references to it. 263 */ 264 obj_zone = uma_zcreate("VM OBJECT", sizeof (struct vm_object), NULL, 265 #ifdef INVARIANTS 266 vm_object_zdtor, 267 #else 268 NULL, 269 #endif 270 vm_object_zinit, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM|UMA_ZONE_NOFREE); 271 } 272 273 void 274 vm_object_clear_flag(vm_object_t object, u_short bits) 275 { 276 277 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 278 object->flags &= ~bits; 279 } 280 281 void 282 vm_object_pip_add(vm_object_t object, short i) 283 { 284 285 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 286 object->paging_in_progress += i; 287 } 288 289 void 290 vm_object_pip_subtract(vm_object_t object, short i) 291 { 292 293 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 294 object->paging_in_progress -= i; 295 } 296 297 void 298 vm_object_pip_wakeup(vm_object_t object) 299 { 300 301 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 302 object->paging_in_progress--; 303 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) { 304 vm_object_clear_flag(object, OBJ_PIPWNT); 305 wakeup(object); 306 } 307 } 308 309 void 310 vm_object_pip_wakeupn(vm_object_t object, short i) 311 { 312 313 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 314 if (i) 315 object->paging_in_progress -= i; 316 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) { 317 vm_object_clear_flag(object, OBJ_PIPWNT); 318 wakeup(object); 319 } 320 } 321 322 void 323 vm_object_pip_wait(vm_object_t object, char *waitid) 324 { 325 326 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 327 while (object->paging_in_progress) { 328 object->flags |= OBJ_PIPWNT; 329 msleep(object, VM_OBJECT_MTX(object), PVM, waitid, 0); 330 } 331 } 332 333 /* 334 * vm_object_allocate: 335 * 336 * Returns a new object with the given size. 337 */ 338 vm_object_t 339 vm_object_allocate(objtype_t type, vm_pindex_t size) 340 { 341 vm_object_t object; 342 343 object = (vm_object_t)uma_zalloc(obj_zone, M_WAITOK); 344 _vm_object_allocate(type, size, object); 345 return (object); 346 } 347 348 349 /* 350 * vm_object_reference: 351 * 352 * Gets another reference to the given object. Note: OBJ_DEAD 353 * objects can be referenced during final cleaning. 354 */ 355 void 356 vm_object_reference(vm_object_t object) 357 { 358 struct vnode *vp; 359 360 if (object == NULL) 361 return; 362 VM_OBJECT_LOCK(object); 363 object->ref_count++; 364 if (object->type == OBJT_VNODE) { 365 int vfslocked; 366 367 vp = object->handle; 368 VM_OBJECT_UNLOCK(object); 369 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 370 vget(vp, LK_RETRY, curthread); 371 VFS_UNLOCK_GIANT(vfslocked); 372 } else 373 VM_OBJECT_UNLOCK(object); 374 } 375 376 /* 377 * vm_object_reference_locked: 378 * 379 * Gets another reference to the given object. 380 * 381 * The object must be locked. 382 */ 383 void 384 vm_object_reference_locked(vm_object_t object) 385 { 386 struct vnode *vp; 387 388 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 389 KASSERT((object->flags & OBJ_DEAD) == 0, 390 ("vm_object_reference_locked: dead object referenced")); 391 object->ref_count++; 392 if (object->type == OBJT_VNODE) { 393 vp = object->handle; 394 vref(vp); 395 } 396 } 397 398 /* 399 * Handle deallocating an object of type OBJT_VNODE. 400 */ 401 static void 402 vm_object_vndeallocate(vm_object_t object) 403 { 404 struct vnode *vp = (struct vnode *) object->handle; 405 406 VFS_ASSERT_GIANT(vp->v_mount); 407 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 408 KASSERT(object->type == OBJT_VNODE, 409 ("vm_object_vndeallocate: not a vnode object")); 410 KASSERT(vp != NULL, ("vm_object_vndeallocate: missing vp")); 411 #ifdef INVARIANTS 412 if (object->ref_count == 0) { 413 vprint("vm_object_vndeallocate", vp); 414 panic("vm_object_vndeallocate: bad object reference count"); 415 } 416 #endif 417 418 object->ref_count--; 419 if (object->ref_count == 0) { 420 mp_fixme("Unlocked vflag access."); 421 vp->v_vflag &= ~VV_TEXT; 422 } 423 VM_OBJECT_UNLOCK(object); 424 /* 425 * vrele may need a vop lock 426 */ 427 vrele(vp); 428 } 429 430 /* 431 * vm_object_deallocate: 432 * 433 * Release a reference to the specified object, 434 * gained either through a vm_object_allocate 435 * or a vm_object_reference call. When all references 436 * are gone, storage associated with this object 437 * may be relinquished. 438 * 439 * No object may be locked. 440 */ 441 void 442 vm_object_deallocate(vm_object_t object) 443 { 444 vm_object_t temp; 445 446 while (object != NULL) { 447 int vfslocked; 448 449 vfslocked = 0; 450 restart: 451 VM_OBJECT_LOCK(object); 452 if (object->type == OBJT_VNODE) { 453 struct vnode *vp = (struct vnode *) object->handle; 454 455 /* 456 * Conditionally acquire Giant for a vnode-backed 457 * object. We have to be careful since the type of 458 * a vnode object can change while the object is 459 * unlocked. 460 */ 461 if (VFS_NEEDSGIANT(vp->v_mount) && !vfslocked) { 462 vfslocked = 1; 463 if (!mtx_trylock(&Giant)) { 464 VM_OBJECT_UNLOCK(object); 465 mtx_lock(&Giant); 466 goto restart; 467 } 468 } 469 vm_object_vndeallocate(object); 470 VFS_UNLOCK_GIANT(vfslocked); 471 return; 472 } else 473 /* 474 * This is to handle the case that the object 475 * changed type while we dropped its lock to 476 * obtain Giant. 477 */ 478 VFS_UNLOCK_GIANT(vfslocked); 479 480 KASSERT(object->ref_count != 0, 481 ("vm_object_deallocate: object deallocated too many times: %d", object->type)); 482 483 /* 484 * If the reference count goes to 0 we start calling 485 * vm_object_terminate() on the object chain. 486 * A ref count of 1 may be a special case depending on the 487 * shadow count being 0 or 1. 488 */ 489 object->ref_count--; 490 if (object->ref_count > 1) { 491 VM_OBJECT_UNLOCK(object); 492 return; 493 } else if (object->ref_count == 1) { 494 if (object->shadow_count == 0) { 495 vm_object_set_flag(object, OBJ_ONEMAPPING); 496 } else if ((object->shadow_count == 1) && 497 (object->handle == NULL) && 498 (object->type == OBJT_DEFAULT || 499 object->type == OBJT_SWAP)) { 500 vm_object_t robject; 501 502 robject = LIST_FIRST(&object->shadow_head); 503 KASSERT(robject != NULL, 504 ("vm_object_deallocate: ref_count: %d, shadow_count: %d", 505 object->ref_count, 506 object->shadow_count)); 507 if (!VM_OBJECT_TRYLOCK(robject)) { 508 /* 509 * Avoid a potential deadlock. 510 */ 511 object->ref_count++; 512 VM_OBJECT_UNLOCK(object); 513 /* 514 * More likely than not the thread 515 * holding robject's lock has lower 516 * priority than the current thread. 517 * Let the lower priority thread run. 518 */ 519 pause("vmo_de", 1); 520 continue; 521 } 522 /* 523 * Collapse object into its shadow unless its 524 * shadow is dead. In that case, object will 525 * be deallocated by the thread that is 526 * deallocating its shadow. 527 */ 528 if ((robject->flags & OBJ_DEAD) == 0 && 529 (robject->handle == NULL) && 530 (robject->type == OBJT_DEFAULT || 531 robject->type == OBJT_SWAP)) { 532 533 robject->ref_count++; 534 retry: 535 if (robject->paging_in_progress) { 536 VM_OBJECT_UNLOCK(object); 537 vm_object_pip_wait(robject, 538 "objde1"); 539 temp = robject->backing_object; 540 if (object == temp) { 541 VM_OBJECT_LOCK(object); 542 goto retry; 543 } 544 } else if (object->paging_in_progress) { 545 VM_OBJECT_UNLOCK(robject); 546 object->flags |= OBJ_PIPWNT; 547 msleep(object, 548 VM_OBJECT_MTX(object), 549 PDROP | PVM, "objde2", 0); 550 VM_OBJECT_LOCK(robject); 551 temp = robject->backing_object; 552 if (object == temp) { 553 VM_OBJECT_LOCK(object); 554 goto retry; 555 } 556 } else 557 VM_OBJECT_UNLOCK(object); 558 559 if (robject->ref_count == 1) { 560 robject->ref_count--; 561 object = robject; 562 goto doterm; 563 } 564 object = robject; 565 vm_object_collapse(object); 566 VM_OBJECT_UNLOCK(object); 567 continue; 568 } 569 VM_OBJECT_UNLOCK(robject); 570 } 571 VM_OBJECT_UNLOCK(object); 572 return; 573 } 574 doterm: 575 temp = object->backing_object; 576 if (temp != NULL) { 577 VM_OBJECT_LOCK(temp); 578 LIST_REMOVE(object, shadow_list); 579 temp->shadow_count--; 580 temp->generation++; 581 VM_OBJECT_UNLOCK(temp); 582 object->backing_object = NULL; 583 } 584 /* 585 * Don't double-terminate, we could be in a termination 586 * recursion due to the terminate having to sync data 587 * to disk. 588 */ 589 if ((object->flags & OBJ_DEAD) == 0) 590 vm_object_terminate(object); 591 else 592 VM_OBJECT_UNLOCK(object); 593 object = temp; 594 } 595 } 596 597 /* 598 * vm_object_terminate actually destroys the specified object, freeing 599 * up all previously used resources. 600 * 601 * The object must be locked. 602 * This routine may block. 603 */ 604 void 605 vm_object_terminate(vm_object_t object) 606 { 607 vm_page_t p; 608 609 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 610 611 /* 612 * Make sure no one uses us. 613 */ 614 vm_object_set_flag(object, OBJ_DEAD); 615 616 /* 617 * wait for the pageout daemon to be done with the object 618 */ 619 vm_object_pip_wait(object, "objtrm"); 620 621 KASSERT(!object->paging_in_progress, 622 ("vm_object_terminate: pageout in progress")); 623 624 /* 625 * Clean and free the pages, as appropriate. All references to the 626 * object are gone, so we don't need to lock it. 627 */ 628 if (object->type == OBJT_VNODE) { 629 struct vnode *vp = (struct vnode *)object->handle; 630 631 /* 632 * Clean pages and flush buffers. 633 */ 634 vm_object_page_clean(object, 0, 0, OBJPC_SYNC); 635 VM_OBJECT_UNLOCK(object); 636 637 vinvalbuf(vp, V_SAVE, NULL, 0, 0); 638 639 VM_OBJECT_LOCK(object); 640 } 641 642 KASSERT(object->ref_count == 0, 643 ("vm_object_terminate: object with references, ref_count=%d", 644 object->ref_count)); 645 646 /* 647 * Now free any remaining pages. For internal objects, this also 648 * removes them from paging queues. Don't free wired pages, just 649 * remove them from the object. 650 */ 651 vm_page_lock_queues(); 652 while ((p = TAILQ_FIRST(&object->memq)) != NULL) { 653 KASSERT(!p->busy && (p->oflags & VPO_BUSY) == 0, 654 ("vm_object_terminate: freeing busy page %p " 655 "p->busy = %d, p->flags %x\n", p, p->busy, p->flags)); 656 if (p->wire_count == 0) { 657 vm_page_free(p); 658 cnt.v_pfree++; 659 } else { 660 vm_page_remove(p); 661 } 662 } 663 vm_page_unlock_queues(); 664 665 /* 666 * Let the pager know object is dead. 667 */ 668 vm_pager_deallocate(object); 669 VM_OBJECT_UNLOCK(object); 670 671 /* 672 * Remove the object from the global object list. 673 */ 674 mtx_lock(&vm_object_list_mtx); 675 TAILQ_REMOVE(&vm_object_list, object, object_list); 676 mtx_unlock(&vm_object_list_mtx); 677 678 /* 679 * Free the space for the object. 680 */ 681 uma_zfree(obj_zone, object); 682 } 683 684 /* 685 * vm_object_page_clean 686 * 687 * Clean all dirty pages in the specified range of object. Leaves page 688 * on whatever queue it is currently on. If NOSYNC is set then do not 689 * write out pages with VPO_NOSYNC set (originally comes from MAP_NOSYNC), 690 * leaving the object dirty. 691 * 692 * When stuffing pages asynchronously, allow clustering. XXX we need a 693 * synchronous clustering mode implementation. 694 * 695 * Odd semantics: if start == end, we clean everything. 696 * 697 * The object must be locked. 698 */ 699 void 700 vm_object_page_clean(vm_object_t object, vm_pindex_t start, vm_pindex_t end, int flags) 701 { 702 vm_page_t p, np; 703 vm_pindex_t tstart, tend; 704 vm_pindex_t pi; 705 int clearobjflags; 706 int pagerflags; 707 int curgeneration; 708 709 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 710 if (object->type != OBJT_VNODE || 711 (object->flags & OBJ_MIGHTBEDIRTY) == 0) 712 return; 713 714 pagerflags = (flags & (OBJPC_SYNC | OBJPC_INVAL)) ? VM_PAGER_PUT_SYNC : VM_PAGER_CLUSTER_OK; 715 pagerflags |= (flags & OBJPC_INVAL) ? VM_PAGER_PUT_INVAL : 0; 716 717 vm_object_set_flag(object, OBJ_CLEANING); 718 719 tstart = start; 720 if (end == 0) { 721 tend = object->size; 722 } else { 723 tend = end; 724 } 725 726 vm_page_lock_queues(); 727 /* 728 * If the caller is smart and only msync()s a range he knows is 729 * dirty, we may be able to avoid an object scan. This results in 730 * a phenominal improvement in performance. We cannot do this 731 * as a matter of course because the object may be huge - e.g. 732 * the size might be in the gigabytes or terrabytes. 733 */ 734 if (msync_flush_flags & MSYNC_FLUSH_HARDSEQ) { 735 vm_pindex_t tscan; 736 int scanlimit; 737 int scanreset; 738 739 scanreset = object->resident_page_count / EASY_SCAN_FACTOR; 740 if (scanreset < 16) 741 scanreset = 16; 742 pagerflags |= VM_PAGER_IGNORE_CLEANCHK; 743 744 scanlimit = scanreset; 745 tscan = tstart; 746 while (tscan < tend) { 747 curgeneration = object->generation; 748 p = vm_page_lookup(object, tscan); 749 if (p == NULL || p->valid == 0 || 750 VM_PAGE_INQUEUE1(p, PQ_CACHE)) { 751 if (--scanlimit == 0) 752 break; 753 ++tscan; 754 continue; 755 } 756 vm_page_test_dirty(p); 757 if ((p->dirty & p->valid) == 0) { 758 if (--scanlimit == 0) 759 break; 760 ++tscan; 761 continue; 762 } 763 /* 764 * If we have been asked to skip nosync pages and 765 * this is a nosync page, we can't continue. 766 */ 767 if ((flags & OBJPC_NOSYNC) && (p->oflags & VPO_NOSYNC)) { 768 if (--scanlimit == 0) 769 break; 770 ++tscan; 771 continue; 772 } 773 scanlimit = scanreset; 774 775 /* 776 * This returns 0 if it was unable to busy the first 777 * page (i.e. had to sleep). 778 */ 779 tscan += vm_object_page_collect_flush(object, p, curgeneration, pagerflags); 780 } 781 782 /* 783 * If everything was dirty and we flushed it successfully, 784 * and the requested range is not the entire object, we 785 * don't have to mess with CLEANCHK or MIGHTBEDIRTY and can 786 * return immediately. 787 */ 788 if (tscan >= tend && (tstart || tend < object->size)) { 789 vm_page_unlock_queues(); 790 vm_object_clear_flag(object, OBJ_CLEANING); 791 return; 792 } 793 pagerflags &= ~VM_PAGER_IGNORE_CLEANCHK; 794 } 795 796 /* 797 * Generally set CLEANCHK interlock and make the page read-only so 798 * we can then clear the object flags. 799 * 800 * However, if this is a nosync mmap then the object is likely to 801 * stay dirty so do not mess with the page and do not clear the 802 * object flags. 803 */ 804 clearobjflags = 1; 805 TAILQ_FOREACH(p, &object->memq, listq) { 806 p->oflags |= VPO_CLEANCHK; 807 if ((flags & OBJPC_NOSYNC) && (p->oflags & VPO_NOSYNC)) 808 clearobjflags = 0; 809 else 810 pmap_remove_write(p); 811 } 812 813 if (clearobjflags && (tstart == 0) && (tend == object->size)) { 814 struct vnode *vp; 815 816 vm_object_clear_flag(object, OBJ_MIGHTBEDIRTY); 817 if (object->type == OBJT_VNODE && 818 (vp = (struct vnode *)object->handle) != NULL) { 819 VI_LOCK(vp); 820 if (vp->v_iflag & VI_OBJDIRTY) 821 vp->v_iflag &= ~VI_OBJDIRTY; 822 VI_UNLOCK(vp); 823 } 824 } 825 826 rescan: 827 curgeneration = object->generation; 828 829 for (p = TAILQ_FIRST(&object->memq); p; p = np) { 830 int n; 831 832 np = TAILQ_NEXT(p, listq); 833 834 again: 835 pi = p->pindex; 836 if ((p->oflags & VPO_CLEANCHK) == 0 || 837 (pi < tstart) || (pi >= tend) || 838 (p->valid == 0) || 839 VM_PAGE_INQUEUE1(p, PQ_CACHE)) { 840 p->oflags &= ~VPO_CLEANCHK; 841 continue; 842 } 843 844 vm_page_test_dirty(p); 845 if ((p->dirty & p->valid) == 0) { 846 p->oflags &= ~VPO_CLEANCHK; 847 continue; 848 } 849 850 /* 851 * If we have been asked to skip nosync pages and this is a 852 * nosync page, skip it. Note that the object flags were 853 * not cleared in this case so we do not have to set them. 854 */ 855 if ((flags & OBJPC_NOSYNC) && (p->oflags & VPO_NOSYNC)) { 856 p->oflags &= ~VPO_CLEANCHK; 857 continue; 858 } 859 860 n = vm_object_page_collect_flush(object, p, 861 curgeneration, pagerflags); 862 if (n == 0) 863 goto rescan; 864 865 if (object->generation != curgeneration) 866 goto rescan; 867 868 /* 869 * Try to optimize the next page. If we can't we pick up 870 * our (random) scan where we left off. 871 */ 872 if (msync_flush_flags & MSYNC_FLUSH_SOFTSEQ) { 873 if ((p = vm_page_lookup(object, pi + n)) != NULL) 874 goto again; 875 } 876 } 877 vm_page_unlock_queues(); 878 #if 0 879 VOP_FSYNC(vp, (pagerflags & VM_PAGER_PUT_SYNC)?MNT_WAIT:0, curproc); 880 #endif 881 882 vm_object_clear_flag(object, OBJ_CLEANING); 883 return; 884 } 885 886 static int 887 vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int curgeneration, int pagerflags) 888 { 889 int runlen; 890 int maxf; 891 int chkb; 892 int maxb; 893 int i; 894 vm_pindex_t pi; 895 vm_page_t maf[vm_pageout_page_count]; 896 vm_page_t mab[vm_pageout_page_count]; 897 vm_page_t ma[vm_pageout_page_count]; 898 899 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 900 pi = p->pindex; 901 while (vm_page_sleep_if_busy(p, TRUE, "vpcwai")) { 902 vm_page_lock_queues(); 903 if (object->generation != curgeneration) { 904 return(0); 905 } 906 } 907 maxf = 0; 908 for(i = 1; i < vm_pageout_page_count; i++) { 909 vm_page_t tp; 910 911 if ((tp = vm_page_lookup(object, pi + i)) != NULL) { 912 if ((tp->oflags & VPO_BUSY) || 913 ((pagerflags & VM_PAGER_IGNORE_CLEANCHK) == 0 && 914 (tp->oflags & VPO_CLEANCHK) == 0) || 915 (tp->busy != 0)) 916 break; 917 if (VM_PAGE_INQUEUE1(tp, PQ_CACHE)) { 918 tp->oflags &= ~VPO_CLEANCHK; 919 break; 920 } 921 vm_page_test_dirty(tp); 922 if ((tp->dirty & tp->valid) == 0) { 923 tp->oflags &= ~VPO_CLEANCHK; 924 break; 925 } 926 maf[ i - 1 ] = tp; 927 maxf++; 928 continue; 929 } 930 break; 931 } 932 933 maxb = 0; 934 chkb = vm_pageout_page_count - maxf; 935 if (chkb) { 936 for(i = 1; i < chkb;i++) { 937 vm_page_t tp; 938 939 if ((tp = vm_page_lookup(object, pi - i)) != NULL) { 940 if ((tp->oflags & VPO_BUSY) || 941 ((pagerflags & VM_PAGER_IGNORE_CLEANCHK) == 0 && 942 (tp->oflags & VPO_CLEANCHK) == 0) || 943 (tp->busy != 0)) 944 break; 945 if (VM_PAGE_INQUEUE1(tp, PQ_CACHE)) { 946 tp->oflags &= ~VPO_CLEANCHK; 947 break; 948 } 949 vm_page_test_dirty(tp); 950 if ((tp->dirty & tp->valid) == 0) { 951 tp->oflags &= ~VPO_CLEANCHK; 952 break; 953 } 954 mab[ i - 1 ] = tp; 955 maxb++; 956 continue; 957 } 958 break; 959 } 960 } 961 962 for(i = 0; i < maxb; i++) { 963 int index = (maxb - i) - 1; 964 ma[index] = mab[i]; 965 ma[index]->oflags &= ~VPO_CLEANCHK; 966 } 967 p->oflags &= ~VPO_CLEANCHK; 968 ma[maxb] = p; 969 for(i = 0; i < maxf; i++) { 970 int index = (maxb + i) + 1; 971 ma[index] = maf[i]; 972 ma[index]->oflags &= ~VPO_CLEANCHK; 973 } 974 runlen = maxb + maxf + 1; 975 976 vm_pageout_flush(ma, runlen, pagerflags); 977 for (i = 0; i < runlen; i++) { 978 if (ma[i]->valid & ma[i]->dirty) { 979 pmap_remove_write(ma[i]); 980 ma[i]->oflags |= VPO_CLEANCHK; 981 982 /* 983 * maxf will end up being the actual number of pages 984 * we wrote out contiguously, non-inclusive of the 985 * first page. We do not count look-behind pages. 986 */ 987 if (i >= maxb + 1 && (maxf > i - maxb - 1)) 988 maxf = i - maxb - 1; 989 } 990 } 991 return(maxf + 1); 992 } 993 994 /* 995 * Note that there is absolutely no sense in writing out 996 * anonymous objects, so we track down the vnode object 997 * to write out. 998 * We invalidate (remove) all pages from the address space 999 * for semantic correctness. 1000 * 1001 * Note: certain anonymous maps, such as MAP_NOSYNC maps, 1002 * may start out with a NULL object. 1003 */ 1004 void 1005 vm_object_sync(vm_object_t object, vm_ooffset_t offset, vm_size_t size, 1006 boolean_t syncio, boolean_t invalidate) 1007 { 1008 vm_object_t backing_object; 1009 struct vnode *vp; 1010 struct mount *mp; 1011 int flags; 1012 1013 if (object == NULL) 1014 return; 1015 VM_OBJECT_LOCK(object); 1016 while ((backing_object = object->backing_object) != NULL) { 1017 VM_OBJECT_LOCK(backing_object); 1018 offset += object->backing_object_offset; 1019 VM_OBJECT_UNLOCK(object); 1020 object = backing_object; 1021 if (object->size < OFF_TO_IDX(offset + size)) 1022 size = IDX_TO_OFF(object->size) - offset; 1023 } 1024 /* 1025 * Flush pages if writing is allowed, invalidate them 1026 * if invalidation requested. Pages undergoing I/O 1027 * will be ignored by vm_object_page_remove(). 1028 * 1029 * We cannot lock the vnode and then wait for paging 1030 * to complete without deadlocking against vm_fault. 1031 * Instead we simply call vm_object_page_remove() and 1032 * allow it to block internally on a page-by-page 1033 * basis when it encounters pages undergoing async 1034 * I/O. 1035 */ 1036 if (object->type == OBJT_VNODE && 1037 (object->flags & OBJ_MIGHTBEDIRTY) != 0) { 1038 int vfslocked; 1039 vp = object->handle; 1040 VM_OBJECT_UNLOCK(object); 1041 (void) vn_start_write(vp, &mp, V_WAIT); 1042 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 1043 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, curthread); 1044 flags = (syncio || invalidate) ? OBJPC_SYNC : 0; 1045 flags |= invalidate ? OBJPC_INVAL : 0; 1046 VM_OBJECT_LOCK(object); 1047 vm_object_page_clean(object, 1048 OFF_TO_IDX(offset), 1049 OFF_TO_IDX(offset + size + PAGE_MASK), 1050 flags); 1051 VM_OBJECT_UNLOCK(object); 1052 VOP_UNLOCK(vp, 0, curthread); 1053 VFS_UNLOCK_GIANT(vfslocked); 1054 vn_finished_write(mp); 1055 VM_OBJECT_LOCK(object); 1056 } 1057 if ((object->type == OBJT_VNODE || 1058 object->type == OBJT_DEVICE) && invalidate) { 1059 boolean_t purge; 1060 purge = old_msync || (object->type == OBJT_DEVICE); 1061 vm_object_page_remove(object, 1062 OFF_TO_IDX(offset), 1063 OFF_TO_IDX(offset + size + PAGE_MASK), 1064 purge ? FALSE : TRUE); 1065 } 1066 VM_OBJECT_UNLOCK(object); 1067 } 1068 1069 /* 1070 * vm_object_madvise: 1071 * 1072 * Implements the madvise function at the object/page level. 1073 * 1074 * MADV_WILLNEED (any object) 1075 * 1076 * Activate the specified pages if they are resident. 1077 * 1078 * MADV_DONTNEED (any object) 1079 * 1080 * Deactivate the specified pages if they are resident. 1081 * 1082 * MADV_FREE (OBJT_DEFAULT/OBJT_SWAP objects, 1083 * OBJ_ONEMAPPING only) 1084 * 1085 * Deactivate and clean the specified pages if they are 1086 * resident. This permits the process to reuse the pages 1087 * without faulting or the kernel to reclaim the pages 1088 * without I/O. 1089 */ 1090 void 1091 vm_object_madvise(vm_object_t object, vm_pindex_t pindex, int count, int advise) 1092 { 1093 vm_pindex_t end, tpindex; 1094 vm_object_t backing_object, tobject; 1095 vm_page_t m; 1096 1097 if (object == NULL) 1098 return; 1099 VM_OBJECT_LOCK(object); 1100 end = pindex + count; 1101 /* 1102 * Locate and adjust resident pages 1103 */ 1104 for (; pindex < end; pindex += 1) { 1105 relookup: 1106 tobject = object; 1107 tpindex = pindex; 1108 shadowlookup: 1109 /* 1110 * MADV_FREE only operates on OBJT_DEFAULT or OBJT_SWAP pages 1111 * and those pages must be OBJ_ONEMAPPING. 1112 */ 1113 if (advise == MADV_FREE) { 1114 if ((tobject->type != OBJT_DEFAULT && 1115 tobject->type != OBJT_SWAP) || 1116 (tobject->flags & OBJ_ONEMAPPING) == 0) { 1117 goto unlock_tobject; 1118 } 1119 } 1120 m = vm_page_lookup(tobject, tpindex); 1121 if (m == NULL) { 1122 /* 1123 * There may be swap even if there is no backing page 1124 */ 1125 if (advise == MADV_FREE && tobject->type == OBJT_SWAP) 1126 swap_pager_freespace(tobject, tpindex, 1); 1127 /* 1128 * next object 1129 */ 1130 backing_object = tobject->backing_object; 1131 if (backing_object == NULL) 1132 goto unlock_tobject; 1133 VM_OBJECT_LOCK(backing_object); 1134 tpindex += OFF_TO_IDX(tobject->backing_object_offset); 1135 if (tobject != object) 1136 VM_OBJECT_UNLOCK(tobject); 1137 tobject = backing_object; 1138 goto shadowlookup; 1139 } 1140 /* 1141 * If the page is busy or not in a normal active state, 1142 * we skip it. If the page is not managed there are no 1143 * page queues to mess with. Things can break if we mess 1144 * with pages in any of the below states. 1145 */ 1146 vm_page_lock_queues(); 1147 if (m->hold_count || 1148 m->wire_count || 1149 (m->flags & PG_UNMANAGED) || 1150 m->valid != VM_PAGE_BITS_ALL) { 1151 vm_page_unlock_queues(); 1152 goto unlock_tobject; 1153 } 1154 if ((m->oflags & VPO_BUSY) || m->busy) { 1155 vm_page_flag_set(m, PG_REFERENCED); 1156 vm_page_unlock_queues(); 1157 if (object != tobject) 1158 VM_OBJECT_UNLOCK(object); 1159 m->oflags |= VPO_WANTED; 1160 msleep(m, VM_OBJECT_MTX(tobject), PDROP | PVM, "madvpo", 0); 1161 VM_OBJECT_LOCK(object); 1162 goto relookup; 1163 } 1164 if (advise == MADV_WILLNEED) { 1165 vm_page_activate(m); 1166 } else if (advise == MADV_DONTNEED) { 1167 vm_page_dontneed(m); 1168 } else if (advise == MADV_FREE) { 1169 /* 1170 * Mark the page clean. This will allow the page 1171 * to be freed up by the system. However, such pages 1172 * are often reused quickly by malloc()/free() 1173 * so we do not do anything that would cause 1174 * a page fault if we can help it. 1175 * 1176 * Specifically, we do not try to actually free 1177 * the page now nor do we try to put it in the 1178 * cache (which would cause a page fault on reuse). 1179 * 1180 * But we do make the page is freeable as we 1181 * can without actually taking the step of unmapping 1182 * it. 1183 */ 1184 pmap_clear_modify(m); 1185 m->dirty = 0; 1186 m->act_count = 0; 1187 vm_page_dontneed(m); 1188 } 1189 vm_page_unlock_queues(); 1190 if (advise == MADV_FREE && tobject->type == OBJT_SWAP) 1191 swap_pager_freespace(tobject, tpindex, 1); 1192 unlock_tobject: 1193 if (tobject != object) 1194 VM_OBJECT_UNLOCK(tobject); 1195 } 1196 VM_OBJECT_UNLOCK(object); 1197 } 1198 1199 /* 1200 * vm_object_shadow: 1201 * 1202 * Create a new object which is backed by the 1203 * specified existing object range. The source 1204 * object reference is deallocated. 1205 * 1206 * The new object and offset into that object 1207 * are returned in the source parameters. 1208 */ 1209 void 1210 vm_object_shadow( 1211 vm_object_t *object, /* IN/OUT */ 1212 vm_ooffset_t *offset, /* IN/OUT */ 1213 vm_size_t length) 1214 { 1215 vm_object_t source; 1216 vm_object_t result; 1217 1218 source = *object; 1219 1220 /* 1221 * Don't create the new object if the old object isn't shared. 1222 */ 1223 if (source != NULL) { 1224 VM_OBJECT_LOCK(source); 1225 if (source->ref_count == 1 && 1226 source->handle == NULL && 1227 (source->type == OBJT_DEFAULT || 1228 source->type == OBJT_SWAP)) { 1229 VM_OBJECT_UNLOCK(source); 1230 return; 1231 } 1232 VM_OBJECT_UNLOCK(source); 1233 } 1234 1235 /* 1236 * Allocate a new object with the given length. 1237 */ 1238 result = vm_object_allocate(OBJT_DEFAULT, length); 1239 1240 /* 1241 * The new object shadows the source object, adding a reference to it. 1242 * Our caller changes his reference to point to the new object, 1243 * removing a reference to the source object. Net result: no change 1244 * of reference count. 1245 * 1246 * Try to optimize the result object's page color when shadowing 1247 * in order to maintain page coloring consistency in the combined 1248 * shadowed object. 1249 */ 1250 result->backing_object = source; 1251 /* 1252 * Store the offset into the source object, and fix up the offset into 1253 * the new object. 1254 */ 1255 result->backing_object_offset = *offset; 1256 if (source != NULL) { 1257 VM_OBJECT_LOCK(source); 1258 LIST_INSERT_HEAD(&source->shadow_head, result, shadow_list); 1259 source->shadow_count++; 1260 source->generation++; 1261 if (length < source->size) 1262 length = source->size; 1263 if (length > PQ_MAXLENGTH || source->generation > 1) 1264 length = PQ_MAXLENGTH; 1265 result->pg_color = (source->pg_color + 1266 length * source->generation) & PQ_COLORMASK; 1267 result->flags |= source->flags & OBJ_NEEDGIANT; 1268 VM_OBJECT_UNLOCK(source); 1269 next_index = (result->pg_color + PQ_MAXLENGTH) & PQ_COLORMASK; 1270 } 1271 1272 1273 /* 1274 * Return the new things 1275 */ 1276 *offset = 0; 1277 *object = result; 1278 } 1279 1280 /* 1281 * vm_object_split: 1282 * 1283 * Split the pages in a map entry into a new object. This affords 1284 * easier removal of unused pages, and keeps object inheritance from 1285 * being a negative impact on memory usage. 1286 */ 1287 void 1288 vm_object_split(vm_map_entry_t entry) 1289 { 1290 vm_page_t m, m_next; 1291 vm_object_t orig_object, new_object, source; 1292 vm_pindex_t idx, offidxstart; 1293 vm_size_t size; 1294 1295 orig_object = entry->object.vm_object; 1296 if (orig_object->type != OBJT_DEFAULT && orig_object->type != OBJT_SWAP) 1297 return; 1298 if (orig_object->ref_count <= 1) 1299 return; 1300 VM_OBJECT_UNLOCK(orig_object); 1301 1302 offidxstart = OFF_TO_IDX(entry->offset); 1303 size = atop(entry->end - entry->start); 1304 1305 /* 1306 * If swap_pager_copy() is later called, it will convert new_object 1307 * into a swap object. 1308 */ 1309 new_object = vm_object_allocate(OBJT_DEFAULT, size); 1310 1311 /* 1312 * At this point, the new object is still private, so the order in 1313 * which the original and new objects are locked does not matter. 1314 */ 1315 VM_OBJECT_LOCK(new_object); 1316 VM_OBJECT_LOCK(orig_object); 1317 source = orig_object->backing_object; 1318 if (source != NULL) { 1319 VM_OBJECT_LOCK(source); 1320 if ((source->flags & OBJ_DEAD) != 0) { 1321 VM_OBJECT_UNLOCK(source); 1322 VM_OBJECT_UNLOCK(orig_object); 1323 VM_OBJECT_UNLOCK(new_object); 1324 vm_object_deallocate(new_object); 1325 VM_OBJECT_LOCK(orig_object); 1326 return; 1327 } 1328 LIST_INSERT_HEAD(&source->shadow_head, 1329 new_object, shadow_list); 1330 source->shadow_count++; 1331 source->generation++; 1332 vm_object_reference_locked(source); /* for new_object */ 1333 vm_object_clear_flag(source, OBJ_ONEMAPPING); 1334 VM_OBJECT_UNLOCK(source); 1335 new_object->backing_object_offset = 1336 orig_object->backing_object_offset + entry->offset; 1337 new_object->backing_object = source; 1338 } 1339 new_object->flags |= orig_object->flags & OBJ_NEEDGIANT; 1340 retry: 1341 if ((m = TAILQ_FIRST(&orig_object->memq)) != NULL) { 1342 if (m->pindex < offidxstart) { 1343 m = vm_page_splay(offidxstart, orig_object->root); 1344 if ((orig_object->root = m)->pindex < offidxstart) 1345 m = TAILQ_NEXT(m, listq); 1346 } 1347 } 1348 vm_page_lock_queues(); 1349 for (; m != NULL && (idx = m->pindex - offidxstart) < size; 1350 m = m_next) { 1351 m_next = TAILQ_NEXT(m, listq); 1352 1353 /* 1354 * We must wait for pending I/O to complete before we can 1355 * rename the page. 1356 * 1357 * We do not have to VM_PROT_NONE the page as mappings should 1358 * not be changed by this operation. 1359 */ 1360 if ((m->oflags & VPO_BUSY) || m->busy) { 1361 vm_page_flag_set(m, PG_REFERENCED); 1362 vm_page_unlock_queues(); 1363 VM_OBJECT_UNLOCK(new_object); 1364 m->oflags |= VPO_WANTED; 1365 msleep(m, VM_OBJECT_MTX(orig_object), PVM, "spltwt", 0); 1366 VM_OBJECT_LOCK(new_object); 1367 goto retry; 1368 } 1369 vm_page_rename(m, new_object, idx); 1370 /* page automatically made dirty by rename and cache handled */ 1371 vm_page_busy(m); 1372 } 1373 vm_page_unlock_queues(); 1374 if (orig_object->type == OBJT_SWAP) { 1375 /* 1376 * swap_pager_copy() can sleep, in which case the orig_object's 1377 * and new_object's locks are released and reacquired. 1378 */ 1379 swap_pager_copy(orig_object, new_object, offidxstart, 0); 1380 } 1381 VM_OBJECT_UNLOCK(orig_object); 1382 TAILQ_FOREACH(m, &new_object->memq, listq) 1383 vm_page_wakeup(m); 1384 VM_OBJECT_UNLOCK(new_object); 1385 entry->object.vm_object = new_object; 1386 entry->offset = 0LL; 1387 vm_object_deallocate(orig_object); 1388 VM_OBJECT_LOCK(new_object); 1389 } 1390 1391 #define OBSC_TEST_ALL_SHADOWED 0x0001 1392 #define OBSC_COLLAPSE_NOWAIT 0x0002 1393 #define OBSC_COLLAPSE_WAIT 0x0004 1394 1395 static int 1396 vm_object_backing_scan(vm_object_t object, int op) 1397 { 1398 int r = 1; 1399 vm_page_t p; 1400 vm_object_t backing_object; 1401 vm_pindex_t backing_offset_index; 1402 1403 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1404 VM_OBJECT_LOCK_ASSERT(object->backing_object, MA_OWNED); 1405 1406 backing_object = object->backing_object; 1407 backing_offset_index = OFF_TO_IDX(object->backing_object_offset); 1408 1409 /* 1410 * Initial conditions 1411 */ 1412 if (op & OBSC_TEST_ALL_SHADOWED) { 1413 /* 1414 * We do not want to have to test for the existence of 1415 * swap pages in the backing object. XXX but with the 1416 * new swapper this would be pretty easy to do. 1417 * 1418 * XXX what about anonymous MAP_SHARED memory that hasn't 1419 * been ZFOD faulted yet? If we do not test for this, the 1420 * shadow test may succeed! XXX 1421 */ 1422 if (backing_object->type != OBJT_DEFAULT) { 1423 return (0); 1424 } 1425 } 1426 if (op & OBSC_COLLAPSE_WAIT) { 1427 vm_object_set_flag(backing_object, OBJ_DEAD); 1428 } 1429 1430 /* 1431 * Our scan 1432 */ 1433 p = TAILQ_FIRST(&backing_object->memq); 1434 while (p) { 1435 vm_page_t next = TAILQ_NEXT(p, listq); 1436 vm_pindex_t new_pindex = p->pindex - backing_offset_index; 1437 1438 if (op & OBSC_TEST_ALL_SHADOWED) { 1439 vm_page_t pp; 1440 1441 /* 1442 * Ignore pages outside the parent object's range 1443 * and outside the parent object's mapping of the 1444 * backing object. 1445 * 1446 * note that we do not busy the backing object's 1447 * page. 1448 */ 1449 if ( 1450 p->pindex < backing_offset_index || 1451 new_pindex >= object->size 1452 ) { 1453 p = next; 1454 continue; 1455 } 1456 1457 /* 1458 * See if the parent has the page or if the parent's 1459 * object pager has the page. If the parent has the 1460 * page but the page is not valid, the parent's 1461 * object pager must have the page. 1462 * 1463 * If this fails, the parent does not completely shadow 1464 * the object and we might as well give up now. 1465 */ 1466 1467 pp = vm_page_lookup(object, new_pindex); 1468 if ( 1469 (pp == NULL || pp->valid == 0) && 1470 !vm_pager_has_page(object, new_pindex, NULL, NULL) 1471 ) { 1472 r = 0; 1473 break; 1474 } 1475 } 1476 1477 /* 1478 * Check for busy page 1479 */ 1480 if (op & (OBSC_COLLAPSE_WAIT | OBSC_COLLAPSE_NOWAIT)) { 1481 vm_page_t pp; 1482 1483 if (op & OBSC_COLLAPSE_NOWAIT) { 1484 if ((p->oflags & VPO_BUSY) || 1485 !p->valid || 1486 p->busy) { 1487 p = next; 1488 continue; 1489 } 1490 } else if (op & OBSC_COLLAPSE_WAIT) { 1491 if ((p->oflags & VPO_BUSY) || p->busy) { 1492 vm_page_lock_queues(); 1493 vm_page_flag_set(p, PG_REFERENCED); 1494 vm_page_unlock_queues(); 1495 VM_OBJECT_UNLOCK(object); 1496 p->oflags |= VPO_WANTED; 1497 msleep(p, VM_OBJECT_MTX(backing_object), 1498 PDROP | PVM, "vmocol", 0); 1499 VM_OBJECT_LOCK(object); 1500 VM_OBJECT_LOCK(backing_object); 1501 /* 1502 * If we slept, anything could have 1503 * happened. Since the object is 1504 * marked dead, the backing offset 1505 * should not have changed so we 1506 * just restart our scan. 1507 */ 1508 p = TAILQ_FIRST(&backing_object->memq); 1509 continue; 1510 } 1511 } 1512 1513 KASSERT( 1514 p->object == backing_object, 1515 ("vm_object_backing_scan: object mismatch") 1516 ); 1517 1518 /* 1519 * Destroy any associated swap 1520 */ 1521 if (backing_object->type == OBJT_SWAP) { 1522 swap_pager_freespace( 1523 backing_object, 1524 p->pindex, 1525 1 1526 ); 1527 } 1528 1529 if ( 1530 p->pindex < backing_offset_index || 1531 new_pindex >= object->size 1532 ) { 1533 /* 1534 * Page is out of the parent object's range, we 1535 * can simply destroy it. 1536 */ 1537 vm_page_lock_queues(); 1538 KASSERT(!pmap_page_is_mapped(p), 1539 ("freeing mapped page %p", p)); 1540 if (p->wire_count == 0) 1541 vm_page_free(p); 1542 else 1543 vm_page_remove(p); 1544 vm_page_unlock_queues(); 1545 p = next; 1546 continue; 1547 } 1548 1549 pp = vm_page_lookup(object, new_pindex); 1550 if ( 1551 pp != NULL || 1552 vm_pager_has_page(object, new_pindex, NULL, NULL) 1553 ) { 1554 /* 1555 * page already exists in parent OR swap exists 1556 * for this location in the parent. Destroy 1557 * the original page from the backing object. 1558 * 1559 * Leave the parent's page alone 1560 */ 1561 vm_page_lock_queues(); 1562 KASSERT(!pmap_page_is_mapped(p), 1563 ("freeing mapped page %p", p)); 1564 if (p->wire_count == 0) 1565 vm_page_free(p); 1566 else 1567 vm_page_remove(p); 1568 vm_page_unlock_queues(); 1569 p = next; 1570 continue; 1571 } 1572 1573 /* 1574 * Page does not exist in parent, rename the 1575 * page from the backing object to the main object. 1576 * 1577 * If the page was mapped to a process, it can remain 1578 * mapped through the rename. 1579 */ 1580 vm_page_lock_queues(); 1581 vm_page_rename(p, object, new_pindex); 1582 vm_page_unlock_queues(); 1583 /* page automatically made dirty by rename */ 1584 } 1585 p = next; 1586 } 1587 return (r); 1588 } 1589 1590 1591 /* 1592 * this version of collapse allows the operation to occur earlier and 1593 * when paging_in_progress is true for an object... This is not a complete 1594 * operation, but should plug 99.9% of the rest of the leaks. 1595 */ 1596 static void 1597 vm_object_qcollapse(vm_object_t object) 1598 { 1599 vm_object_t backing_object = object->backing_object; 1600 1601 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1602 VM_OBJECT_LOCK_ASSERT(backing_object, MA_OWNED); 1603 1604 if (backing_object->ref_count != 1) 1605 return; 1606 1607 vm_object_backing_scan(object, OBSC_COLLAPSE_NOWAIT); 1608 } 1609 1610 /* 1611 * vm_object_collapse: 1612 * 1613 * Collapse an object with the object backing it. 1614 * Pages in the backing object are moved into the 1615 * parent, and the backing object is deallocated. 1616 */ 1617 void 1618 vm_object_collapse(vm_object_t object) 1619 { 1620 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1621 1622 while (TRUE) { 1623 vm_object_t backing_object; 1624 1625 /* 1626 * Verify that the conditions are right for collapse: 1627 * 1628 * The object exists and the backing object exists. 1629 */ 1630 if ((backing_object = object->backing_object) == NULL) 1631 break; 1632 1633 /* 1634 * we check the backing object first, because it is most likely 1635 * not collapsable. 1636 */ 1637 VM_OBJECT_LOCK(backing_object); 1638 if (backing_object->handle != NULL || 1639 (backing_object->type != OBJT_DEFAULT && 1640 backing_object->type != OBJT_SWAP) || 1641 (backing_object->flags & OBJ_DEAD) || 1642 object->handle != NULL || 1643 (object->type != OBJT_DEFAULT && 1644 object->type != OBJT_SWAP) || 1645 (object->flags & OBJ_DEAD)) { 1646 VM_OBJECT_UNLOCK(backing_object); 1647 break; 1648 } 1649 1650 if ( 1651 object->paging_in_progress != 0 || 1652 backing_object->paging_in_progress != 0 1653 ) { 1654 vm_object_qcollapse(object); 1655 VM_OBJECT_UNLOCK(backing_object); 1656 break; 1657 } 1658 /* 1659 * We know that we can either collapse the backing object (if 1660 * the parent is the only reference to it) or (perhaps) have 1661 * the parent bypass the object if the parent happens to shadow 1662 * all the resident pages in the entire backing object. 1663 * 1664 * This is ignoring pager-backed pages such as swap pages. 1665 * vm_object_backing_scan fails the shadowing test in this 1666 * case. 1667 */ 1668 if (backing_object->ref_count == 1) { 1669 /* 1670 * If there is exactly one reference to the backing 1671 * object, we can collapse it into the parent. 1672 */ 1673 vm_object_backing_scan(object, OBSC_COLLAPSE_WAIT); 1674 1675 /* 1676 * Move the pager from backing_object to object. 1677 */ 1678 if (backing_object->type == OBJT_SWAP) { 1679 /* 1680 * swap_pager_copy() can sleep, in which case 1681 * the backing_object's and object's locks are 1682 * released and reacquired. 1683 */ 1684 swap_pager_copy( 1685 backing_object, 1686 object, 1687 OFF_TO_IDX(object->backing_object_offset), TRUE); 1688 } 1689 /* 1690 * Object now shadows whatever backing_object did. 1691 * Note that the reference to 1692 * backing_object->backing_object moves from within 1693 * backing_object to within object. 1694 */ 1695 LIST_REMOVE(object, shadow_list); 1696 backing_object->shadow_count--; 1697 backing_object->generation++; 1698 if (backing_object->backing_object) { 1699 VM_OBJECT_LOCK(backing_object->backing_object); 1700 LIST_REMOVE(backing_object, shadow_list); 1701 LIST_INSERT_HEAD( 1702 &backing_object->backing_object->shadow_head, 1703 object, shadow_list); 1704 /* 1705 * The shadow_count has not changed. 1706 */ 1707 backing_object->backing_object->generation++; 1708 VM_OBJECT_UNLOCK(backing_object->backing_object); 1709 } 1710 object->backing_object = backing_object->backing_object; 1711 object->backing_object_offset += 1712 backing_object->backing_object_offset; 1713 1714 /* 1715 * Discard backing_object. 1716 * 1717 * Since the backing object has no pages, no pager left, 1718 * and no object references within it, all that is 1719 * necessary is to dispose of it. 1720 */ 1721 KASSERT(backing_object->ref_count == 1, ("backing_object %p was somehow re-referenced during collapse!", backing_object)); 1722 VM_OBJECT_UNLOCK(backing_object); 1723 1724 mtx_lock(&vm_object_list_mtx); 1725 TAILQ_REMOVE( 1726 &vm_object_list, 1727 backing_object, 1728 object_list 1729 ); 1730 mtx_unlock(&vm_object_list_mtx); 1731 1732 uma_zfree(obj_zone, backing_object); 1733 1734 object_collapses++; 1735 } else { 1736 vm_object_t new_backing_object; 1737 1738 /* 1739 * If we do not entirely shadow the backing object, 1740 * there is nothing we can do so we give up. 1741 */ 1742 if (object->resident_page_count != object->size && 1743 vm_object_backing_scan(object, 1744 OBSC_TEST_ALL_SHADOWED) == 0) { 1745 VM_OBJECT_UNLOCK(backing_object); 1746 break; 1747 } 1748 1749 /* 1750 * Make the parent shadow the next object in the 1751 * chain. Deallocating backing_object will not remove 1752 * it, since its reference count is at least 2. 1753 */ 1754 LIST_REMOVE(object, shadow_list); 1755 backing_object->shadow_count--; 1756 backing_object->generation++; 1757 1758 new_backing_object = backing_object->backing_object; 1759 if ((object->backing_object = new_backing_object) != NULL) { 1760 VM_OBJECT_LOCK(new_backing_object); 1761 LIST_INSERT_HEAD( 1762 &new_backing_object->shadow_head, 1763 object, 1764 shadow_list 1765 ); 1766 new_backing_object->shadow_count++; 1767 new_backing_object->generation++; 1768 vm_object_reference_locked(new_backing_object); 1769 VM_OBJECT_UNLOCK(new_backing_object); 1770 object->backing_object_offset += 1771 backing_object->backing_object_offset; 1772 } 1773 1774 /* 1775 * Drop the reference count on backing_object. Since 1776 * its ref_count was at least 2, it will not vanish. 1777 */ 1778 backing_object->ref_count--; 1779 VM_OBJECT_UNLOCK(backing_object); 1780 object_bypasses++; 1781 } 1782 1783 /* 1784 * Try again with this object's new backing object. 1785 */ 1786 } 1787 } 1788 1789 /* 1790 * vm_object_page_remove: 1791 * 1792 * Removes all physical pages in the given range from the 1793 * object's list of pages. If the range's end is zero, all 1794 * physical pages from the range's start to the end of the object 1795 * are deleted. 1796 * 1797 * The object must be locked. 1798 */ 1799 void 1800 vm_object_page_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end, 1801 boolean_t clean_only) 1802 { 1803 vm_page_t p, next; 1804 1805 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1806 if (object->resident_page_count == 0) 1807 return; 1808 1809 /* 1810 * Since physically-backed objects do not use managed pages, we can't 1811 * remove pages from the object (we must instead remove the page 1812 * references, and then destroy the object). 1813 */ 1814 KASSERT(object->type != OBJT_PHYS || object == kernel_object || 1815 object == kmem_object, 1816 ("attempt to remove pages from a physical object")); 1817 1818 vm_object_pip_add(object, 1); 1819 again: 1820 vm_page_lock_queues(); 1821 if ((p = TAILQ_FIRST(&object->memq)) != NULL) { 1822 if (p->pindex < start) { 1823 p = vm_page_splay(start, object->root); 1824 if ((object->root = p)->pindex < start) 1825 p = TAILQ_NEXT(p, listq); 1826 } 1827 } 1828 /* 1829 * Assert: the variable p is either (1) the page with the 1830 * least pindex greater than or equal to the parameter pindex 1831 * or (2) NULL. 1832 */ 1833 for (; 1834 p != NULL && (p->pindex < end || end == 0); 1835 p = next) { 1836 next = TAILQ_NEXT(p, listq); 1837 1838 if (p->wire_count != 0) { 1839 pmap_remove_all(p); 1840 if (!clean_only) 1841 p->valid = 0; 1842 continue; 1843 } 1844 if (vm_page_sleep_if_busy(p, TRUE, "vmopar")) 1845 goto again; 1846 if (clean_only && p->valid) { 1847 pmap_remove_write(p); 1848 if (p->valid & p->dirty) 1849 continue; 1850 } 1851 pmap_remove_all(p); 1852 vm_page_free(p); 1853 } 1854 vm_page_unlock_queues(); 1855 vm_object_pip_wakeup(object); 1856 } 1857 1858 /* 1859 * Routine: vm_object_coalesce 1860 * Function: Coalesces two objects backing up adjoining 1861 * regions of memory into a single object. 1862 * 1863 * returns TRUE if objects were combined. 1864 * 1865 * NOTE: Only works at the moment if the second object is NULL - 1866 * if it's not, which object do we lock first? 1867 * 1868 * Parameters: 1869 * prev_object First object to coalesce 1870 * prev_offset Offset into prev_object 1871 * prev_size Size of reference to prev_object 1872 * next_size Size of reference to the second object 1873 * 1874 * Conditions: 1875 * The object must *not* be locked. 1876 */ 1877 boolean_t 1878 vm_object_coalesce(vm_object_t prev_object, vm_ooffset_t prev_offset, 1879 vm_size_t prev_size, vm_size_t next_size) 1880 { 1881 vm_pindex_t next_pindex; 1882 1883 if (prev_object == NULL) 1884 return (TRUE); 1885 VM_OBJECT_LOCK(prev_object); 1886 if (prev_object->type != OBJT_DEFAULT && 1887 prev_object->type != OBJT_SWAP) { 1888 VM_OBJECT_UNLOCK(prev_object); 1889 return (FALSE); 1890 } 1891 1892 /* 1893 * Try to collapse the object first 1894 */ 1895 vm_object_collapse(prev_object); 1896 1897 /* 1898 * Can't coalesce if: . more than one reference . paged out . shadows 1899 * another object . has a copy elsewhere (any of which mean that the 1900 * pages not mapped to prev_entry may be in use anyway) 1901 */ 1902 if (prev_object->backing_object != NULL) { 1903 VM_OBJECT_UNLOCK(prev_object); 1904 return (FALSE); 1905 } 1906 1907 prev_size >>= PAGE_SHIFT; 1908 next_size >>= PAGE_SHIFT; 1909 next_pindex = OFF_TO_IDX(prev_offset) + prev_size; 1910 1911 if ((prev_object->ref_count > 1) && 1912 (prev_object->size != next_pindex)) { 1913 VM_OBJECT_UNLOCK(prev_object); 1914 return (FALSE); 1915 } 1916 1917 /* 1918 * Remove any pages that may still be in the object from a previous 1919 * deallocation. 1920 */ 1921 if (next_pindex < prev_object->size) { 1922 vm_object_page_remove(prev_object, 1923 next_pindex, 1924 next_pindex + next_size, FALSE); 1925 if (prev_object->type == OBJT_SWAP) 1926 swap_pager_freespace(prev_object, 1927 next_pindex, next_size); 1928 } 1929 1930 /* 1931 * Extend the object if necessary. 1932 */ 1933 if (next_pindex + next_size > prev_object->size) 1934 prev_object->size = next_pindex + next_size; 1935 1936 VM_OBJECT_UNLOCK(prev_object); 1937 return (TRUE); 1938 } 1939 1940 void 1941 vm_object_set_writeable_dirty(vm_object_t object) 1942 { 1943 struct vnode *vp; 1944 1945 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1946 if ((object->flags & OBJ_MIGHTBEDIRTY) != 0) 1947 return; 1948 vm_object_set_flag(object, OBJ_MIGHTBEDIRTY); 1949 if (object->type == OBJT_VNODE && 1950 (vp = (struct vnode *)object->handle) != NULL) { 1951 VI_LOCK(vp); 1952 vp->v_iflag |= VI_OBJDIRTY; 1953 VI_UNLOCK(vp); 1954 } 1955 } 1956 1957 #include "opt_ddb.h" 1958 #ifdef DDB 1959 #include <sys/kernel.h> 1960 1961 #include <sys/cons.h> 1962 1963 #include <ddb/ddb.h> 1964 1965 static int 1966 _vm_object_in_map(vm_map_t map, vm_object_t object, vm_map_entry_t entry) 1967 { 1968 vm_map_t tmpm; 1969 vm_map_entry_t tmpe; 1970 vm_object_t obj; 1971 int entcount; 1972 1973 if (map == 0) 1974 return 0; 1975 1976 if (entry == 0) { 1977 tmpe = map->header.next; 1978 entcount = map->nentries; 1979 while (entcount-- && (tmpe != &map->header)) { 1980 if (_vm_object_in_map(map, object, tmpe)) { 1981 return 1; 1982 } 1983 tmpe = tmpe->next; 1984 } 1985 } else if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) { 1986 tmpm = entry->object.sub_map; 1987 tmpe = tmpm->header.next; 1988 entcount = tmpm->nentries; 1989 while (entcount-- && tmpe != &tmpm->header) { 1990 if (_vm_object_in_map(tmpm, object, tmpe)) { 1991 return 1; 1992 } 1993 tmpe = tmpe->next; 1994 } 1995 } else if ((obj = entry->object.vm_object) != NULL) { 1996 for (; obj; obj = obj->backing_object) 1997 if (obj == object) { 1998 return 1; 1999 } 2000 } 2001 return 0; 2002 } 2003 2004 static int 2005 vm_object_in_map(vm_object_t object) 2006 { 2007 struct proc *p; 2008 2009 /* sx_slock(&allproc_lock); */ 2010 FOREACH_PROC_IN_SYSTEM(p) { 2011 if (!p->p_vmspace /* || (p->p_flag & (P_SYSTEM|P_WEXIT)) */) 2012 continue; 2013 if (_vm_object_in_map(&p->p_vmspace->vm_map, object, 0)) { 2014 /* sx_sunlock(&allproc_lock); */ 2015 return 1; 2016 } 2017 } 2018 /* sx_sunlock(&allproc_lock); */ 2019 if (_vm_object_in_map(kernel_map, object, 0)) 2020 return 1; 2021 if (_vm_object_in_map(kmem_map, object, 0)) 2022 return 1; 2023 if (_vm_object_in_map(pager_map, object, 0)) 2024 return 1; 2025 if (_vm_object_in_map(buffer_map, object, 0)) 2026 return 1; 2027 return 0; 2028 } 2029 2030 DB_SHOW_COMMAND(vmochk, vm_object_check) 2031 { 2032 vm_object_t object; 2033 2034 /* 2035 * make sure that internal objs are in a map somewhere 2036 * and none have zero ref counts. 2037 */ 2038 TAILQ_FOREACH(object, &vm_object_list, object_list) { 2039 if (object->handle == NULL && 2040 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) { 2041 if (object->ref_count == 0) { 2042 db_printf("vmochk: internal obj has zero ref count: %ld\n", 2043 (long)object->size); 2044 } 2045 if (!vm_object_in_map(object)) { 2046 db_printf( 2047 "vmochk: internal obj is not in a map: " 2048 "ref: %d, size: %lu: 0x%lx, backing_object: %p\n", 2049 object->ref_count, (u_long)object->size, 2050 (u_long)object->size, 2051 (void *)object->backing_object); 2052 } 2053 } 2054 } 2055 } 2056 2057 /* 2058 * vm_object_print: [ debug ] 2059 */ 2060 DB_SHOW_COMMAND(object, vm_object_print_static) 2061 { 2062 /* XXX convert args. */ 2063 vm_object_t object = (vm_object_t)addr; 2064 boolean_t full = have_addr; 2065 2066 vm_page_t p; 2067 2068 /* XXX count is an (unused) arg. Avoid shadowing it. */ 2069 #define count was_count 2070 2071 int count; 2072 2073 if (object == NULL) 2074 return; 2075 2076 db_iprintf( 2077 "Object %p: type=%d, size=0x%jx, res=%d, ref=%d, flags=0x%x\n", 2078 object, (int)object->type, (uintmax_t)object->size, 2079 object->resident_page_count, object->ref_count, object->flags); 2080 db_iprintf(" sref=%d, backing_object(%d)=(%p)+0x%jx\n", 2081 object->shadow_count, 2082 object->backing_object ? object->backing_object->ref_count : 0, 2083 object->backing_object, (uintmax_t)object->backing_object_offset); 2084 2085 if (!full) 2086 return; 2087 2088 db_indent += 2; 2089 count = 0; 2090 TAILQ_FOREACH(p, &object->memq, listq) { 2091 if (count == 0) 2092 db_iprintf("memory:="); 2093 else if (count == 6) { 2094 db_printf("\n"); 2095 db_iprintf(" ..."); 2096 count = 0; 2097 } else 2098 db_printf(","); 2099 count++; 2100 2101 db_printf("(off=0x%jx,page=0x%jx)", 2102 (uintmax_t)p->pindex, (uintmax_t)VM_PAGE_TO_PHYS(p)); 2103 } 2104 if (count != 0) 2105 db_printf("\n"); 2106 db_indent -= 2; 2107 } 2108 2109 /* XXX. */ 2110 #undef count 2111 2112 /* XXX need this non-static entry for calling from vm_map_print. */ 2113 void 2114 vm_object_print( 2115 /* db_expr_t */ long addr, 2116 boolean_t have_addr, 2117 /* db_expr_t */ long count, 2118 char *modif) 2119 { 2120 vm_object_print_static(addr, have_addr, count, modif); 2121 } 2122 2123 DB_SHOW_COMMAND(vmopag, vm_object_print_pages) 2124 { 2125 vm_object_t object; 2126 int nl = 0; 2127 int c; 2128 2129 TAILQ_FOREACH(object, &vm_object_list, object_list) { 2130 vm_pindex_t idx, fidx; 2131 vm_pindex_t osize; 2132 vm_paddr_t pa = -1, padiff; 2133 int rcount; 2134 vm_page_t m; 2135 2136 db_printf("new object: %p\n", (void *)object); 2137 if (nl > 18) { 2138 c = cngetc(); 2139 if (c != ' ') 2140 return; 2141 nl = 0; 2142 } 2143 nl++; 2144 rcount = 0; 2145 fidx = 0; 2146 osize = object->size; 2147 if (osize > 128) 2148 osize = 128; 2149 for (idx = 0; idx < osize; idx++) { 2150 m = vm_page_lookup(object, idx); 2151 if (m == NULL) { 2152 if (rcount) { 2153 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2154 (long)fidx, rcount, (long)pa); 2155 if (nl > 18) { 2156 c = cngetc(); 2157 if (c != ' ') 2158 return; 2159 nl = 0; 2160 } 2161 nl++; 2162 rcount = 0; 2163 } 2164 continue; 2165 } 2166 2167 2168 if (rcount && 2169 (VM_PAGE_TO_PHYS(m) == pa + rcount * PAGE_SIZE)) { 2170 ++rcount; 2171 continue; 2172 } 2173 if (rcount) { 2174 padiff = pa + rcount * PAGE_SIZE - VM_PAGE_TO_PHYS(m); 2175 padiff >>= PAGE_SHIFT; 2176 padiff &= PQ_COLORMASK; 2177 if (padiff == 0) { 2178 pa = VM_PAGE_TO_PHYS(m) - rcount * PAGE_SIZE; 2179 ++rcount; 2180 continue; 2181 } 2182 db_printf(" index(%ld)run(%d)pa(0x%lx)", 2183 (long)fidx, rcount, (long)pa); 2184 db_printf("pd(%ld)\n", (long)padiff); 2185 if (nl > 18) { 2186 c = cngetc(); 2187 if (c != ' ') 2188 return; 2189 nl = 0; 2190 } 2191 nl++; 2192 } 2193 fidx = idx; 2194 pa = VM_PAGE_TO_PHYS(m); 2195 rcount = 1; 2196 } 2197 if (rcount) { 2198 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2199 (long)fidx, rcount, (long)pa); 2200 if (nl > 18) { 2201 c = cngetc(); 2202 if (c != ' ') 2203 return; 2204 nl = 0; 2205 } 2206 nl++; 2207 } 2208 } 2209 } 2210 #endif /* DDB */ 2211