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 "opt_vm.h" 69 70 #include <sys/param.h> 71 #include <sys/systm.h> 72 #include <sys/lock.h> 73 #include <sys/mman.h> 74 #include <sys/mount.h> 75 #include <sys/kernel.h> 76 #include <sys/sysctl.h> 77 #include <sys/mutex.h> 78 #include <sys/proc.h> /* for curproc, pageproc */ 79 #include <sys/socket.h> 80 #include <sys/resourcevar.h> 81 #include <sys/vnode.h> 82 #include <sys/vmmeter.h> 83 #include <sys/sx.h> 84 85 #include <vm/vm.h> 86 #include <vm/vm_param.h> 87 #include <vm/pmap.h> 88 #include <vm/vm_map.h> 89 #include <vm/vm_object.h> 90 #include <vm/vm_page.h> 91 #include <vm/vm_pageout.h> 92 #include <vm/vm_pager.h> 93 #include <vm/swap_pager.h> 94 #include <vm/vm_kern.h> 95 #include <vm/vm_extern.h> 96 #include <vm/vm_reserv.h> 97 #include <vm/uma.h> 98 99 static int old_msync; 100 SYSCTL_INT(_vm, OID_AUTO, old_msync, CTLFLAG_RW, &old_msync, 0, 101 "Use old (insecure) msync behavior"); 102 103 static int vm_object_page_collect_flush(vm_object_t object, vm_page_t p, 104 int pagerflags); 105 static void vm_object_qcollapse(vm_object_t object); 106 static void vm_object_vndeallocate(vm_object_t object); 107 108 /* 109 * Virtual memory objects maintain the actual data 110 * associated with allocated virtual memory. A given 111 * page of memory exists within exactly one object. 112 * 113 * An object is only deallocated when all "references" 114 * are given up. Only one "reference" to a given 115 * region of an object should be writeable. 116 * 117 * Associated with each object is a list of all resident 118 * memory pages belonging to that object; this list is 119 * maintained by the "vm_page" module, and locked by the object's 120 * lock. 121 * 122 * Each object also records a "pager" routine which is 123 * used to retrieve (and store) pages to the proper backing 124 * storage. In addition, objects may be backed by other 125 * objects from which they were virtual-copied. 126 * 127 * The only items within the object structure which are 128 * modified after time of creation are: 129 * reference count locked by object's lock 130 * pager routine locked by object's lock 131 * 132 */ 133 134 struct object_q vm_object_list; 135 struct mtx vm_object_list_mtx; /* lock for object list and count */ 136 137 struct vm_object kernel_object_store; 138 struct vm_object kmem_object_store; 139 140 SYSCTL_NODE(_vm_stats, OID_AUTO, object, CTLFLAG_RD, 0, "VM object stats"); 141 142 static long object_collapses; 143 SYSCTL_LONG(_vm_stats_object, OID_AUTO, collapses, CTLFLAG_RD, 144 &object_collapses, 0, "VM object collapses"); 145 146 static long object_bypasses; 147 SYSCTL_LONG(_vm_stats_object, OID_AUTO, bypasses, CTLFLAG_RD, 148 &object_bypasses, 0, "VM object bypasses"); 149 150 static uma_zone_t obj_zone; 151 152 static int vm_object_zinit(void *mem, int size, int flags); 153 154 #ifdef INVARIANTS 155 static void vm_object_zdtor(void *mem, int size, void *arg); 156 157 static void 158 vm_object_zdtor(void *mem, int size, void *arg) 159 { 160 vm_object_t object; 161 162 object = (vm_object_t)mem; 163 KASSERT(TAILQ_EMPTY(&object->memq), 164 ("object %p has resident pages", 165 object)); 166 #if VM_NRESERVLEVEL > 0 167 KASSERT(LIST_EMPTY(&object->rvq), 168 ("object %p has reservations", 169 object)); 170 #endif 171 KASSERT(object->cache == NULL, 172 ("object %p has cached pages", 173 object)); 174 KASSERT(object->paging_in_progress == 0, 175 ("object %p paging_in_progress = %d", 176 object, object->paging_in_progress)); 177 KASSERT(object->resident_page_count == 0, 178 ("object %p resident_page_count = %d", 179 object, object->resident_page_count)); 180 KASSERT(object->shadow_count == 0, 181 ("object %p shadow_count = %d", 182 object, object->shadow_count)); 183 } 184 #endif 185 186 static int 187 vm_object_zinit(void *mem, int size, int flags) 188 { 189 vm_object_t object; 190 191 object = (vm_object_t)mem; 192 bzero(&object->mtx, sizeof(object->mtx)); 193 VM_OBJECT_LOCK_INIT(object, "standard object"); 194 195 /* These are true for any object that has been freed */ 196 object->paging_in_progress = 0; 197 object->resident_page_count = 0; 198 object->shadow_count = 0; 199 return (0); 200 } 201 202 void 203 _vm_object_allocate(objtype_t type, vm_pindex_t size, vm_object_t object) 204 { 205 206 TAILQ_INIT(&object->memq); 207 LIST_INIT(&object->shadow_head); 208 209 object->root = NULL; 210 object->type = type; 211 object->size = size; 212 object->generation = 1; 213 object->ref_count = 1; 214 object->memattr = VM_MEMATTR_DEFAULT; 215 object->flags = 0; 216 object->cred = NULL; 217 object->charge = 0; 218 if ((object->type == OBJT_DEFAULT) || (object->type == OBJT_SWAP)) 219 object->flags = OBJ_ONEMAPPING; 220 object->pg_color = 0; 221 object->handle = NULL; 222 object->backing_object = NULL; 223 object->backing_object_offset = (vm_ooffset_t) 0; 224 #if VM_NRESERVLEVEL > 0 225 LIST_INIT(&object->rvq); 226 #endif 227 object->cache = NULL; 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_PHYS, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS), 247 kernel_object); 248 #if VM_NRESERVLEVEL > 0 249 kernel_object->flags |= OBJ_COLORED; 250 kernel_object->pg_color = (u_short)atop(VM_MIN_KERNEL_ADDRESS); 251 #endif 252 253 VM_OBJECT_LOCK_INIT(&kmem_object_store, "kmem object"); 254 _vm_object_allocate(OBJT_PHYS, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS), 255 kmem_object); 256 #if VM_NRESERVLEVEL > 0 257 kmem_object->flags |= OBJ_COLORED; 258 kmem_object->pg_color = (u_short)atop(VM_MIN_KERNEL_ADDRESS); 259 #endif 260 261 /* 262 * The lock portion of struct vm_object must be type stable due 263 * to vm_pageout_fallback_object_lock locking a vm object 264 * without holding any references to it. 265 */ 266 obj_zone = uma_zcreate("VM OBJECT", sizeof (struct vm_object), NULL, 267 #ifdef INVARIANTS 268 vm_object_zdtor, 269 #else 270 NULL, 271 #endif 272 vm_object_zinit, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM|UMA_ZONE_NOFREE); 273 } 274 275 void 276 vm_object_clear_flag(vm_object_t object, u_short bits) 277 { 278 279 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 280 object->flags &= ~bits; 281 } 282 283 /* 284 * Sets the default memory attribute for the specified object. Pages 285 * that are allocated to this object are by default assigned this memory 286 * attribute. 287 * 288 * Presently, this function must be called before any pages are allocated 289 * to the object. In the future, this requirement may be relaxed for 290 * "default" and "swap" objects. 291 */ 292 int 293 vm_object_set_memattr(vm_object_t object, vm_memattr_t memattr) 294 { 295 296 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 297 switch (object->type) { 298 case OBJT_DEFAULT: 299 case OBJT_DEVICE: 300 case OBJT_PHYS: 301 case OBJT_SG: 302 case OBJT_SWAP: 303 case OBJT_VNODE: 304 if (!TAILQ_EMPTY(&object->memq)) 305 return (KERN_FAILURE); 306 break; 307 case OBJT_DEAD: 308 return (KERN_INVALID_ARGUMENT); 309 } 310 object->memattr = memattr; 311 return (KERN_SUCCESS); 312 } 313 314 void 315 vm_object_pip_add(vm_object_t object, short i) 316 { 317 318 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 319 object->paging_in_progress += i; 320 } 321 322 void 323 vm_object_pip_subtract(vm_object_t object, short i) 324 { 325 326 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 327 object->paging_in_progress -= i; 328 } 329 330 void 331 vm_object_pip_wakeup(vm_object_t object) 332 { 333 334 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 335 object->paging_in_progress--; 336 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) { 337 vm_object_clear_flag(object, OBJ_PIPWNT); 338 wakeup(object); 339 } 340 } 341 342 void 343 vm_object_pip_wakeupn(vm_object_t object, short i) 344 { 345 346 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 347 if (i) 348 object->paging_in_progress -= i; 349 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) { 350 vm_object_clear_flag(object, OBJ_PIPWNT); 351 wakeup(object); 352 } 353 } 354 355 void 356 vm_object_pip_wait(vm_object_t object, char *waitid) 357 { 358 359 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 360 while (object->paging_in_progress) { 361 object->flags |= OBJ_PIPWNT; 362 msleep(object, VM_OBJECT_MTX(object), PVM, waitid, 0); 363 } 364 } 365 366 /* 367 * vm_object_allocate: 368 * 369 * Returns a new object with the given size. 370 */ 371 vm_object_t 372 vm_object_allocate(objtype_t type, vm_pindex_t size) 373 { 374 vm_object_t object; 375 376 object = (vm_object_t)uma_zalloc(obj_zone, M_WAITOK); 377 _vm_object_allocate(type, size, object); 378 return (object); 379 } 380 381 382 /* 383 * vm_object_reference: 384 * 385 * Gets another reference to the given object. Note: OBJ_DEAD 386 * objects can be referenced during final cleaning. 387 */ 388 void 389 vm_object_reference(vm_object_t object) 390 { 391 if (object == NULL) 392 return; 393 VM_OBJECT_LOCK(object); 394 vm_object_reference_locked(object); 395 VM_OBJECT_UNLOCK(object); 396 } 397 398 /* 399 * vm_object_reference_locked: 400 * 401 * Gets another reference to the given object. 402 * 403 * The object must be locked. 404 */ 405 void 406 vm_object_reference_locked(vm_object_t object) 407 { 408 struct vnode *vp; 409 410 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 411 object->ref_count++; 412 if (object->type == OBJT_VNODE) { 413 vp = object->handle; 414 vref(vp); 415 } 416 } 417 418 /* 419 * Handle deallocating an object of type OBJT_VNODE. 420 */ 421 static void 422 vm_object_vndeallocate(vm_object_t object) 423 { 424 struct vnode *vp = (struct vnode *) object->handle; 425 426 VFS_ASSERT_GIANT(vp->v_mount); 427 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 428 KASSERT(object->type == OBJT_VNODE, 429 ("vm_object_vndeallocate: not a vnode object")); 430 KASSERT(vp != NULL, ("vm_object_vndeallocate: missing vp")); 431 #ifdef INVARIANTS 432 if (object->ref_count == 0) { 433 vprint("vm_object_vndeallocate", vp); 434 panic("vm_object_vndeallocate: bad object reference count"); 435 } 436 #endif 437 438 object->ref_count--; 439 if (object->ref_count == 0) { 440 mp_fixme("Unlocked vflag access."); 441 vp->v_vflag &= ~VV_TEXT; 442 } 443 VM_OBJECT_UNLOCK(object); 444 /* 445 * vrele may need a vop lock 446 */ 447 vrele(vp); 448 } 449 450 /* 451 * vm_object_deallocate: 452 * 453 * Release a reference to the specified object, 454 * gained either through a vm_object_allocate 455 * or a vm_object_reference call. When all references 456 * are gone, storage associated with this object 457 * may be relinquished. 458 * 459 * No object may be locked. 460 */ 461 void 462 vm_object_deallocate(vm_object_t object) 463 { 464 vm_object_t temp; 465 466 while (object != NULL) { 467 int vfslocked; 468 469 vfslocked = 0; 470 restart: 471 VM_OBJECT_LOCK(object); 472 if (object->type == OBJT_VNODE) { 473 struct vnode *vp = (struct vnode *) object->handle; 474 475 /* 476 * Conditionally acquire Giant for a vnode-backed 477 * object. We have to be careful since the type of 478 * a vnode object can change while the object is 479 * unlocked. 480 */ 481 if (VFS_NEEDSGIANT(vp->v_mount) && !vfslocked) { 482 vfslocked = 1; 483 if (!mtx_trylock(&Giant)) { 484 VM_OBJECT_UNLOCK(object); 485 mtx_lock(&Giant); 486 goto restart; 487 } 488 } 489 vm_object_vndeallocate(object); 490 VFS_UNLOCK_GIANT(vfslocked); 491 return; 492 } else 493 /* 494 * This is to handle the case that the object 495 * changed type while we dropped its lock to 496 * obtain Giant. 497 */ 498 VFS_UNLOCK_GIANT(vfslocked); 499 500 KASSERT(object->ref_count != 0, 501 ("vm_object_deallocate: object deallocated too many times: %d", object->type)); 502 503 /* 504 * If the reference count goes to 0 we start calling 505 * vm_object_terminate() on the object chain. 506 * A ref count of 1 may be a special case depending on the 507 * shadow count being 0 or 1. 508 */ 509 object->ref_count--; 510 if (object->ref_count > 1) { 511 VM_OBJECT_UNLOCK(object); 512 return; 513 } else if (object->ref_count == 1) { 514 if (object->shadow_count == 0 && 515 object->handle == NULL && 516 (object->type == OBJT_DEFAULT || 517 object->type == OBJT_SWAP)) { 518 vm_object_set_flag(object, OBJ_ONEMAPPING); 519 } else if ((object->shadow_count == 1) && 520 (object->handle == NULL) && 521 (object->type == OBJT_DEFAULT || 522 object->type == OBJT_SWAP)) { 523 vm_object_t robject; 524 525 robject = LIST_FIRST(&object->shadow_head); 526 KASSERT(robject != NULL, 527 ("vm_object_deallocate: ref_count: %d, shadow_count: %d", 528 object->ref_count, 529 object->shadow_count)); 530 if (!VM_OBJECT_TRYLOCK(robject)) { 531 /* 532 * Avoid a potential deadlock. 533 */ 534 object->ref_count++; 535 VM_OBJECT_UNLOCK(object); 536 /* 537 * More likely than not the thread 538 * holding robject's lock has lower 539 * priority than the current thread. 540 * Let the lower priority thread run. 541 */ 542 pause("vmo_de", 1); 543 continue; 544 } 545 /* 546 * Collapse object into its shadow unless its 547 * shadow is dead. In that case, object will 548 * be deallocated by the thread that is 549 * deallocating its shadow. 550 */ 551 if ((robject->flags & OBJ_DEAD) == 0 && 552 (robject->handle == NULL) && 553 (robject->type == OBJT_DEFAULT || 554 robject->type == OBJT_SWAP)) { 555 556 robject->ref_count++; 557 retry: 558 if (robject->paging_in_progress) { 559 VM_OBJECT_UNLOCK(object); 560 vm_object_pip_wait(robject, 561 "objde1"); 562 temp = robject->backing_object; 563 if (object == temp) { 564 VM_OBJECT_LOCK(object); 565 goto retry; 566 } 567 } else if (object->paging_in_progress) { 568 VM_OBJECT_UNLOCK(robject); 569 object->flags |= OBJ_PIPWNT; 570 msleep(object, 571 VM_OBJECT_MTX(object), 572 PDROP | PVM, "objde2", 0); 573 VM_OBJECT_LOCK(robject); 574 temp = robject->backing_object; 575 if (object == temp) { 576 VM_OBJECT_LOCK(object); 577 goto retry; 578 } 579 } else 580 VM_OBJECT_UNLOCK(object); 581 582 if (robject->ref_count == 1) { 583 robject->ref_count--; 584 object = robject; 585 goto doterm; 586 } 587 object = robject; 588 vm_object_collapse(object); 589 VM_OBJECT_UNLOCK(object); 590 continue; 591 } 592 VM_OBJECT_UNLOCK(robject); 593 } 594 VM_OBJECT_UNLOCK(object); 595 return; 596 } 597 doterm: 598 temp = object->backing_object; 599 if (temp != NULL) { 600 VM_OBJECT_LOCK(temp); 601 LIST_REMOVE(object, shadow_list); 602 temp->shadow_count--; 603 VM_OBJECT_UNLOCK(temp); 604 object->backing_object = NULL; 605 } 606 /* 607 * Don't double-terminate, we could be in a termination 608 * recursion due to the terminate having to sync data 609 * to disk. 610 */ 611 if ((object->flags & OBJ_DEAD) == 0) 612 vm_object_terminate(object); 613 else 614 VM_OBJECT_UNLOCK(object); 615 object = temp; 616 } 617 } 618 619 /* 620 * vm_object_destroy removes the object from the global object list 621 * and frees the space for the object. 622 */ 623 void 624 vm_object_destroy(vm_object_t object) 625 { 626 627 /* 628 * Remove the object from the global object list. 629 */ 630 mtx_lock(&vm_object_list_mtx); 631 TAILQ_REMOVE(&vm_object_list, object, object_list); 632 mtx_unlock(&vm_object_list_mtx); 633 634 /* 635 * Release the allocation charge. 636 */ 637 if (object->cred != NULL) { 638 KASSERT(object->type == OBJT_DEFAULT || 639 object->type == OBJT_SWAP, 640 ("vm_object_terminate: non-swap obj %p has cred", 641 object)); 642 swap_release_by_cred(object->charge, object->cred); 643 object->charge = 0; 644 crfree(object->cred); 645 object->cred = NULL; 646 } 647 648 /* 649 * Free the space for the object. 650 */ 651 uma_zfree(obj_zone, object); 652 } 653 654 /* 655 * vm_object_terminate actually destroys the specified object, freeing 656 * up all previously used resources. 657 * 658 * The object must be locked. 659 * This routine may block. 660 */ 661 void 662 vm_object_terminate(vm_object_t object) 663 { 664 vm_page_t p, p_next; 665 666 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 667 668 /* 669 * Make sure no one uses us. 670 */ 671 vm_object_set_flag(object, OBJ_DEAD); 672 673 /* 674 * wait for the pageout daemon to be done with the object 675 */ 676 vm_object_pip_wait(object, "objtrm"); 677 678 KASSERT(!object->paging_in_progress, 679 ("vm_object_terminate: pageout in progress")); 680 681 /* 682 * Clean and free the pages, as appropriate. All references to the 683 * object are gone, so we don't need to lock it. 684 */ 685 if (object->type == OBJT_VNODE) { 686 struct vnode *vp = (struct vnode *)object->handle; 687 688 /* 689 * Clean pages and flush buffers. 690 */ 691 vm_object_page_clean(object, 0, 0, OBJPC_SYNC); 692 VM_OBJECT_UNLOCK(object); 693 694 vinvalbuf(vp, V_SAVE, 0, 0); 695 696 VM_OBJECT_LOCK(object); 697 } 698 699 KASSERT(object->ref_count == 0, 700 ("vm_object_terminate: object with references, ref_count=%d", 701 object->ref_count)); 702 703 /* 704 * Free any remaining pageable pages. This also removes them from the 705 * paging queues. However, don't free wired pages, just remove them 706 * from the object. Rather than incrementally removing each page from 707 * the object, the page and object are reset to any empty state. 708 */ 709 TAILQ_FOREACH_SAFE(p, &object->memq, listq, p_next) { 710 KASSERT(!p->busy && (p->oflags & VPO_BUSY) == 0, 711 ("vm_object_terminate: freeing busy page %p", p)); 712 vm_page_lock(p); 713 /* 714 * Optimize the page's removal from the object by resetting 715 * its "object" field. Specifically, if the page is not 716 * wired, then the effect of this assignment is that 717 * vm_page_free()'s call to vm_page_remove() will return 718 * immediately without modifying the page or the object. 719 */ 720 p->object = NULL; 721 if (p->wire_count == 0) { 722 vm_page_free(p); 723 PCPU_INC(cnt.v_pfree); 724 } 725 vm_page_unlock(p); 726 } 727 /* 728 * If the object contained any pages, then reset it to an empty state. 729 * None of the object's fields, including "resident_page_count", were 730 * modified by the preceding loop. 731 */ 732 if (object->resident_page_count != 0) { 733 object->root = NULL; 734 TAILQ_INIT(&object->memq); 735 object->resident_page_count = 0; 736 if (object->type == OBJT_VNODE) 737 vdrop(object->handle); 738 } 739 740 #if VM_NRESERVLEVEL > 0 741 if (__predict_false(!LIST_EMPTY(&object->rvq))) 742 vm_reserv_break_all(object); 743 #endif 744 if (__predict_false(object->cache != NULL)) 745 vm_page_cache_free(object, 0, 0); 746 747 /* 748 * Let the pager know object is dead. 749 */ 750 vm_pager_deallocate(object); 751 VM_OBJECT_UNLOCK(object); 752 753 vm_object_destroy(object); 754 } 755 756 /* 757 * vm_object_page_clean 758 * 759 * Clean all dirty pages in the specified range of object. Leaves page 760 * on whatever queue it is currently on. If NOSYNC is set then do not 761 * write out pages with VPO_NOSYNC set (originally comes from MAP_NOSYNC), 762 * leaving the object dirty. 763 * 764 * When stuffing pages asynchronously, allow clustering. XXX we need a 765 * synchronous clustering mode implementation. 766 * 767 * Odd semantics: if start == end, we clean everything. 768 * 769 * The object must be locked. 770 */ 771 void 772 vm_object_page_clean(vm_object_t object, vm_pindex_t start, vm_pindex_t end, 773 int flags) 774 { 775 vm_page_t np, p; 776 vm_pindex_t pi, tend; 777 int clearobjflags, curgeneration, n, pagerflags; 778 779 mtx_assert(&vm_page_queue_mtx, MA_NOTOWNED); 780 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 781 KASSERT(object->type == OBJT_VNODE, ("Not a vnode object")); 782 if ((object->flags & OBJ_MIGHTBEDIRTY) == 0 || 783 object->resident_page_count == 0) 784 return; 785 786 pagerflags = (flags & (OBJPC_SYNC | OBJPC_INVAL)) != 0 ? 787 VM_PAGER_PUT_SYNC : VM_PAGER_CLUSTER_OK; 788 pagerflags |= (flags & OBJPC_INVAL) != 0 ? VM_PAGER_PUT_INVAL : 0; 789 790 tend = (end == 0) ? object->size : end; 791 792 vm_object_set_flag(object, OBJ_CLEANING); 793 794 /* 795 * Make the page read-only so we can then clear the object flags. 796 * 797 * However, if this is a nosync mmap then the object is likely to 798 * stay dirty so do not mess with the page and do not clear the 799 * object flags. 800 */ 801 clearobjflags = 1; 802 for (p = vm_page_find_least(object, start); 803 p != NULL && p->pindex < tend; p = TAILQ_NEXT(p, listq)) { 804 if ((flags & OBJPC_NOSYNC) != 0 && 805 (p->oflags & VPO_NOSYNC) != 0) 806 clearobjflags = 0; 807 else 808 pmap_remove_write(p); 809 } 810 811 if (clearobjflags && (start == 0) && (tend == object->size)) 812 vm_object_clear_flag(object, OBJ_MIGHTBEDIRTY); 813 814 rescan: 815 curgeneration = object->generation; 816 817 for (p = vm_page_find_least(object, start); p != NULL; p = np) { 818 pi = p->pindex; 819 if (pi >= tend) 820 break; 821 np = TAILQ_NEXT(p, listq); 822 if (p->valid == 0) 823 continue; 824 if (vm_page_sleep_if_busy(p, TRUE, "vpcwai")) { 825 if (object->generation != curgeneration) 826 goto rescan; 827 np = vm_page_find_least(object, pi); 828 continue; 829 } 830 vm_page_test_dirty(p); 831 if (p->dirty == 0) 832 continue; 833 834 /* 835 * If we have been asked to skip nosync pages and this is a 836 * nosync page, skip it. Note that the object flags were 837 * not cleared in this case so we do not have to set them. 838 */ 839 if ((flags & OBJPC_NOSYNC) != 0 && 840 (p->oflags & VPO_NOSYNC) != 0) 841 continue; 842 843 n = vm_object_page_collect_flush(object, p, pagerflags); 844 if (object->generation != curgeneration) 845 goto rescan; 846 np = vm_page_find_least(object, pi + n); 847 } 848 #if 0 849 VOP_FSYNC(vp, (pagerflags & VM_PAGER_PUT_SYNC) ? MNT_WAIT : 0); 850 #endif 851 852 vm_object_clear_flag(object, OBJ_CLEANING); 853 } 854 855 static int 856 vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int pagerflags) 857 { 858 vm_page_t ma[vm_pageout_page_count], p_first, tp; 859 int count, i, mreq, runlen; 860 861 mtx_assert(&vm_page_queue_mtx, MA_NOTOWNED); 862 vm_page_lock_assert(p, MA_NOTOWNED); 863 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 864 865 count = 1; 866 mreq = 0; 867 868 for (tp = p; count < vm_pageout_page_count; count++) { 869 tp = vm_page_next(tp); 870 if (tp == NULL || tp->busy != 0 || (tp->oflags & VPO_BUSY) != 0) 871 break; 872 vm_page_test_dirty(tp); 873 if (tp->dirty == 0) 874 break; 875 } 876 877 for (p_first = p; count < vm_pageout_page_count; count++) { 878 tp = vm_page_prev(p_first); 879 if (tp == NULL || tp->busy != 0 || (tp->oflags & VPO_BUSY) != 0) 880 break; 881 vm_page_test_dirty(tp); 882 if (tp->dirty == 0) 883 break; 884 p_first = tp; 885 mreq++; 886 } 887 888 for (tp = p_first, i = 0; i < count; tp = TAILQ_NEXT(tp, listq), i++) 889 ma[i] = tp; 890 891 vm_pageout_flush(ma, count, pagerflags, mreq, &runlen); 892 return (runlen); 893 } 894 895 /* 896 * Note that there is absolutely no sense in writing out 897 * anonymous objects, so we track down the vnode object 898 * to write out. 899 * We invalidate (remove) all pages from the address space 900 * for semantic correctness. 901 * 902 * Note: certain anonymous maps, such as MAP_NOSYNC maps, 903 * may start out with a NULL object. 904 */ 905 void 906 vm_object_sync(vm_object_t object, vm_ooffset_t offset, vm_size_t size, 907 boolean_t syncio, boolean_t invalidate) 908 { 909 vm_object_t backing_object; 910 struct vnode *vp; 911 struct mount *mp; 912 int flags; 913 914 if (object == NULL) 915 return; 916 VM_OBJECT_LOCK(object); 917 while ((backing_object = object->backing_object) != NULL) { 918 VM_OBJECT_LOCK(backing_object); 919 offset += object->backing_object_offset; 920 VM_OBJECT_UNLOCK(object); 921 object = backing_object; 922 if (object->size < OFF_TO_IDX(offset + size)) 923 size = IDX_TO_OFF(object->size) - offset; 924 } 925 /* 926 * Flush pages if writing is allowed, invalidate them 927 * if invalidation requested. Pages undergoing I/O 928 * will be ignored by vm_object_page_remove(). 929 * 930 * We cannot lock the vnode and then wait for paging 931 * to complete without deadlocking against vm_fault. 932 * Instead we simply call vm_object_page_remove() and 933 * allow it to block internally on a page-by-page 934 * basis when it encounters pages undergoing async 935 * I/O. 936 */ 937 if (object->type == OBJT_VNODE && 938 (object->flags & OBJ_MIGHTBEDIRTY) != 0) { 939 int vfslocked; 940 vp = object->handle; 941 VM_OBJECT_UNLOCK(object); 942 (void) vn_start_write(vp, &mp, V_WAIT); 943 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 944 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 945 flags = (syncio || invalidate) ? OBJPC_SYNC : 0; 946 flags |= invalidate ? OBJPC_INVAL : 0; 947 VM_OBJECT_LOCK(object); 948 vm_object_page_clean(object, 949 OFF_TO_IDX(offset), 950 OFF_TO_IDX(offset + size + PAGE_MASK), 951 flags); 952 VM_OBJECT_UNLOCK(object); 953 VOP_UNLOCK(vp, 0); 954 VFS_UNLOCK_GIANT(vfslocked); 955 vn_finished_write(mp); 956 VM_OBJECT_LOCK(object); 957 } 958 if ((object->type == OBJT_VNODE || 959 object->type == OBJT_DEVICE) && invalidate) { 960 boolean_t purge; 961 purge = old_msync || (object->type == OBJT_DEVICE); 962 vm_object_page_remove(object, 963 OFF_TO_IDX(offset), 964 OFF_TO_IDX(offset + size + PAGE_MASK), 965 purge ? FALSE : TRUE); 966 } 967 VM_OBJECT_UNLOCK(object); 968 } 969 970 /* 971 * vm_object_madvise: 972 * 973 * Implements the madvise function at the object/page level. 974 * 975 * MADV_WILLNEED (any object) 976 * 977 * Activate the specified pages if they are resident. 978 * 979 * MADV_DONTNEED (any object) 980 * 981 * Deactivate the specified pages if they are resident. 982 * 983 * MADV_FREE (OBJT_DEFAULT/OBJT_SWAP objects, 984 * OBJ_ONEMAPPING only) 985 * 986 * Deactivate and clean the specified pages if they are 987 * resident. This permits the process to reuse the pages 988 * without faulting or the kernel to reclaim the pages 989 * without I/O. 990 */ 991 void 992 vm_object_madvise(vm_object_t object, vm_pindex_t pindex, int count, int advise) 993 { 994 vm_pindex_t end, tpindex; 995 vm_object_t backing_object, tobject; 996 vm_page_t m; 997 998 if (object == NULL) 999 return; 1000 VM_OBJECT_LOCK(object); 1001 end = pindex + count; 1002 /* 1003 * Locate and adjust resident pages 1004 */ 1005 for (; pindex < end; pindex += 1) { 1006 relookup: 1007 tobject = object; 1008 tpindex = pindex; 1009 shadowlookup: 1010 /* 1011 * MADV_FREE only operates on OBJT_DEFAULT or OBJT_SWAP pages 1012 * and those pages must be OBJ_ONEMAPPING. 1013 */ 1014 if (advise == MADV_FREE) { 1015 if ((tobject->type != OBJT_DEFAULT && 1016 tobject->type != OBJT_SWAP) || 1017 (tobject->flags & OBJ_ONEMAPPING) == 0) { 1018 goto unlock_tobject; 1019 } 1020 } else if (tobject->type == OBJT_PHYS) 1021 goto unlock_tobject; 1022 m = vm_page_lookup(tobject, tpindex); 1023 if (m == NULL && advise == MADV_WILLNEED) { 1024 /* 1025 * If the page is cached, reactivate it. 1026 */ 1027 m = vm_page_alloc(tobject, tpindex, VM_ALLOC_IFCACHED | 1028 VM_ALLOC_NOBUSY); 1029 } 1030 if (m == NULL) { 1031 /* 1032 * There may be swap even if there is no backing page 1033 */ 1034 if (advise == MADV_FREE && tobject->type == OBJT_SWAP) 1035 swap_pager_freespace(tobject, tpindex, 1); 1036 /* 1037 * next object 1038 */ 1039 backing_object = tobject->backing_object; 1040 if (backing_object == NULL) 1041 goto unlock_tobject; 1042 VM_OBJECT_LOCK(backing_object); 1043 tpindex += OFF_TO_IDX(tobject->backing_object_offset); 1044 if (tobject != object) 1045 VM_OBJECT_UNLOCK(tobject); 1046 tobject = backing_object; 1047 goto shadowlookup; 1048 } else if (m->valid != VM_PAGE_BITS_ALL) 1049 goto unlock_tobject; 1050 /* 1051 * If the page is not in a normal state, skip it. 1052 */ 1053 vm_page_lock(m); 1054 if (m->hold_count != 0 || m->wire_count != 0) { 1055 vm_page_unlock(m); 1056 goto unlock_tobject; 1057 } 1058 KASSERT((m->flags & (PG_FICTITIOUS | PG_UNMANAGED)) == 0, 1059 ("vm_object_madvise: page %p is not managed", m)); 1060 if ((m->oflags & VPO_BUSY) || m->busy) { 1061 if (advise == MADV_WILLNEED) { 1062 /* 1063 * Reference the page before unlocking and 1064 * sleeping so that the page daemon is less 1065 * likely to reclaim it. 1066 */ 1067 vm_page_lock_queues(); 1068 vm_page_flag_set(m, PG_REFERENCED); 1069 vm_page_unlock_queues(); 1070 } 1071 vm_page_unlock(m); 1072 if (object != tobject) 1073 VM_OBJECT_UNLOCK(object); 1074 m->oflags |= VPO_WANTED; 1075 msleep(m, VM_OBJECT_MTX(tobject), PDROP | PVM, "madvpo", 1076 0); 1077 VM_OBJECT_LOCK(object); 1078 goto relookup; 1079 } 1080 if (advise == MADV_WILLNEED) { 1081 vm_page_activate(m); 1082 } else if (advise == MADV_DONTNEED) { 1083 vm_page_dontneed(m); 1084 } else if (advise == MADV_FREE) { 1085 /* 1086 * Mark the page clean. This will allow the page 1087 * to be freed up by the system. However, such pages 1088 * are often reused quickly by malloc()/free() 1089 * so we do not do anything that would cause 1090 * a page fault if we can help it. 1091 * 1092 * Specifically, we do not try to actually free 1093 * the page now nor do we try to put it in the 1094 * cache (which would cause a page fault on reuse). 1095 * 1096 * But we do make the page is freeable as we 1097 * can without actually taking the step of unmapping 1098 * it. 1099 */ 1100 pmap_clear_modify(m); 1101 m->dirty = 0; 1102 m->act_count = 0; 1103 vm_page_dontneed(m); 1104 } 1105 vm_page_unlock(m); 1106 if (advise == MADV_FREE && tobject->type == OBJT_SWAP) 1107 swap_pager_freespace(tobject, tpindex, 1); 1108 unlock_tobject: 1109 if (tobject != object) 1110 VM_OBJECT_UNLOCK(tobject); 1111 } 1112 VM_OBJECT_UNLOCK(object); 1113 } 1114 1115 /* 1116 * vm_object_shadow: 1117 * 1118 * Create a new object which is backed by the 1119 * specified existing object range. The source 1120 * object reference is deallocated. 1121 * 1122 * The new object and offset into that object 1123 * are returned in the source parameters. 1124 */ 1125 void 1126 vm_object_shadow( 1127 vm_object_t *object, /* IN/OUT */ 1128 vm_ooffset_t *offset, /* IN/OUT */ 1129 vm_size_t length) 1130 { 1131 vm_object_t source; 1132 vm_object_t result; 1133 1134 source = *object; 1135 1136 /* 1137 * Don't create the new object if the old object isn't shared. 1138 */ 1139 if (source != NULL) { 1140 VM_OBJECT_LOCK(source); 1141 if (source->ref_count == 1 && 1142 source->handle == NULL && 1143 (source->type == OBJT_DEFAULT || 1144 source->type == OBJT_SWAP)) { 1145 VM_OBJECT_UNLOCK(source); 1146 return; 1147 } 1148 VM_OBJECT_UNLOCK(source); 1149 } 1150 1151 /* 1152 * Allocate a new object with the given length. 1153 */ 1154 result = vm_object_allocate(OBJT_DEFAULT, length); 1155 1156 /* 1157 * The new object shadows the source object, adding a reference to it. 1158 * Our caller changes his reference to point to the new object, 1159 * removing a reference to the source object. Net result: no change 1160 * of reference count. 1161 * 1162 * Try to optimize the result object's page color when shadowing 1163 * in order to maintain page coloring consistency in the combined 1164 * shadowed object. 1165 */ 1166 result->backing_object = source; 1167 /* 1168 * Store the offset into the source object, and fix up the offset into 1169 * the new object. 1170 */ 1171 result->backing_object_offset = *offset; 1172 if (source != NULL) { 1173 VM_OBJECT_LOCK(source); 1174 LIST_INSERT_HEAD(&source->shadow_head, result, shadow_list); 1175 source->shadow_count++; 1176 #if VM_NRESERVLEVEL > 0 1177 result->flags |= source->flags & OBJ_COLORED; 1178 result->pg_color = (source->pg_color + OFF_TO_IDX(*offset)) & 1179 ((1 << (VM_NFREEORDER - 1)) - 1); 1180 #endif 1181 VM_OBJECT_UNLOCK(source); 1182 } 1183 1184 1185 /* 1186 * Return the new things 1187 */ 1188 *offset = 0; 1189 *object = result; 1190 } 1191 1192 /* 1193 * vm_object_split: 1194 * 1195 * Split the pages in a map entry into a new object. This affords 1196 * easier removal of unused pages, and keeps object inheritance from 1197 * being a negative impact on memory usage. 1198 */ 1199 void 1200 vm_object_split(vm_map_entry_t entry) 1201 { 1202 vm_page_t m, m_next; 1203 vm_object_t orig_object, new_object, source; 1204 vm_pindex_t idx, offidxstart; 1205 vm_size_t size; 1206 1207 orig_object = entry->object.vm_object; 1208 if (orig_object->type != OBJT_DEFAULT && orig_object->type != OBJT_SWAP) 1209 return; 1210 if (orig_object->ref_count <= 1) 1211 return; 1212 VM_OBJECT_UNLOCK(orig_object); 1213 1214 offidxstart = OFF_TO_IDX(entry->offset); 1215 size = atop(entry->end - entry->start); 1216 1217 /* 1218 * If swap_pager_copy() is later called, it will convert new_object 1219 * into a swap object. 1220 */ 1221 new_object = vm_object_allocate(OBJT_DEFAULT, size); 1222 1223 /* 1224 * At this point, the new object is still private, so the order in 1225 * which the original and new objects are locked does not matter. 1226 */ 1227 VM_OBJECT_LOCK(new_object); 1228 VM_OBJECT_LOCK(orig_object); 1229 source = orig_object->backing_object; 1230 if (source != NULL) { 1231 VM_OBJECT_LOCK(source); 1232 if ((source->flags & OBJ_DEAD) != 0) { 1233 VM_OBJECT_UNLOCK(source); 1234 VM_OBJECT_UNLOCK(orig_object); 1235 VM_OBJECT_UNLOCK(new_object); 1236 vm_object_deallocate(new_object); 1237 VM_OBJECT_LOCK(orig_object); 1238 return; 1239 } 1240 LIST_INSERT_HEAD(&source->shadow_head, 1241 new_object, shadow_list); 1242 source->shadow_count++; 1243 vm_object_reference_locked(source); /* for new_object */ 1244 vm_object_clear_flag(source, OBJ_ONEMAPPING); 1245 VM_OBJECT_UNLOCK(source); 1246 new_object->backing_object_offset = 1247 orig_object->backing_object_offset + entry->offset; 1248 new_object->backing_object = source; 1249 } 1250 if (orig_object->cred != NULL) { 1251 new_object->cred = orig_object->cred; 1252 crhold(orig_object->cred); 1253 new_object->charge = ptoa(size); 1254 KASSERT(orig_object->charge >= ptoa(size), 1255 ("orig_object->charge < 0")); 1256 orig_object->charge -= ptoa(size); 1257 } 1258 retry: 1259 m = vm_page_find_least(orig_object, offidxstart); 1260 for (; m != NULL && (idx = m->pindex - offidxstart) < size; 1261 m = m_next) { 1262 m_next = TAILQ_NEXT(m, listq); 1263 1264 /* 1265 * We must wait for pending I/O to complete before we can 1266 * rename the page. 1267 * 1268 * We do not have to VM_PROT_NONE the page as mappings should 1269 * not be changed by this operation. 1270 */ 1271 if ((m->oflags & VPO_BUSY) || m->busy) { 1272 VM_OBJECT_UNLOCK(new_object); 1273 m->oflags |= VPO_WANTED; 1274 msleep(m, VM_OBJECT_MTX(orig_object), PVM, "spltwt", 0); 1275 VM_OBJECT_LOCK(new_object); 1276 goto retry; 1277 } 1278 vm_page_lock(m); 1279 vm_page_rename(m, new_object, idx); 1280 vm_page_unlock(m); 1281 /* page automatically made dirty by rename and cache handled */ 1282 vm_page_busy(m); 1283 } 1284 if (orig_object->type == OBJT_SWAP) { 1285 /* 1286 * swap_pager_copy() can sleep, in which case the orig_object's 1287 * and new_object's locks are released and reacquired. 1288 */ 1289 swap_pager_copy(orig_object, new_object, offidxstart, 0); 1290 1291 /* 1292 * Transfer any cached pages from orig_object to new_object. 1293 */ 1294 if (__predict_false(orig_object->cache != NULL)) 1295 vm_page_cache_transfer(orig_object, offidxstart, 1296 new_object); 1297 } 1298 VM_OBJECT_UNLOCK(orig_object); 1299 TAILQ_FOREACH(m, &new_object->memq, listq) 1300 vm_page_wakeup(m); 1301 VM_OBJECT_UNLOCK(new_object); 1302 entry->object.vm_object = new_object; 1303 entry->offset = 0LL; 1304 vm_object_deallocate(orig_object); 1305 VM_OBJECT_LOCK(new_object); 1306 } 1307 1308 #define OBSC_TEST_ALL_SHADOWED 0x0001 1309 #define OBSC_COLLAPSE_NOWAIT 0x0002 1310 #define OBSC_COLLAPSE_WAIT 0x0004 1311 1312 static int 1313 vm_object_backing_scan(vm_object_t object, int op) 1314 { 1315 int r = 1; 1316 vm_page_t p; 1317 vm_object_t backing_object; 1318 vm_pindex_t backing_offset_index; 1319 1320 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1321 VM_OBJECT_LOCK_ASSERT(object->backing_object, MA_OWNED); 1322 1323 backing_object = object->backing_object; 1324 backing_offset_index = OFF_TO_IDX(object->backing_object_offset); 1325 1326 /* 1327 * Initial conditions 1328 */ 1329 if (op & OBSC_TEST_ALL_SHADOWED) { 1330 /* 1331 * We do not want to have to test for the existence of cache 1332 * or swap pages in the backing object. XXX but with the 1333 * new swapper this would be pretty easy to do. 1334 * 1335 * XXX what about anonymous MAP_SHARED memory that hasn't 1336 * been ZFOD faulted yet? If we do not test for this, the 1337 * shadow test may succeed! XXX 1338 */ 1339 if (backing_object->type != OBJT_DEFAULT) { 1340 return (0); 1341 } 1342 } 1343 if (op & OBSC_COLLAPSE_WAIT) { 1344 vm_object_set_flag(backing_object, OBJ_DEAD); 1345 } 1346 1347 /* 1348 * Our scan 1349 */ 1350 p = TAILQ_FIRST(&backing_object->memq); 1351 while (p) { 1352 vm_page_t next = TAILQ_NEXT(p, listq); 1353 vm_pindex_t new_pindex = p->pindex - backing_offset_index; 1354 1355 if (op & OBSC_TEST_ALL_SHADOWED) { 1356 vm_page_t pp; 1357 1358 /* 1359 * Ignore pages outside the parent object's range 1360 * and outside the parent object's mapping of the 1361 * backing object. 1362 * 1363 * note that we do not busy the backing object's 1364 * page. 1365 */ 1366 if ( 1367 p->pindex < backing_offset_index || 1368 new_pindex >= object->size 1369 ) { 1370 p = next; 1371 continue; 1372 } 1373 1374 /* 1375 * See if the parent has the page or if the parent's 1376 * object pager has the page. If the parent has the 1377 * page but the page is not valid, the parent's 1378 * object pager must have the page. 1379 * 1380 * If this fails, the parent does not completely shadow 1381 * the object and we might as well give up now. 1382 */ 1383 1384 pp = vm_page_lookup(object, new_pindex); 1385 if ( 1386 (pp == NULL || pp->valid == 0) && 1387 !vm_pager_has_page(object, new_pindex, NULL, NULL) 1388 ) { 1389 r = 0; 1390 break; 1391 } 1392 } 1393 1394 /* 1395 * Check for busy page 1396 */ 1397 if (op & (OBSC_COLLAPSE_WAIT | OBSC_COLLAPSE_NOWAIT)) { 1398 vm_page_t pp; 1399 1400 if (op & OBSC_COLLAPSE_NOWAIT) { 1401 if ((p->oflags & VPO_BUSY) || 1402 !p->valid || 1403 p->busy) { 1404 p = next; 1405 continue; 1406 } 1407 } else if (op & OBSC_COLLAPSE_WAIT) { 1408 if ((p->oflags & VPO_BUSY) || p->busy) { 1409 VM_OBJECT_UNLOCK(object); 1410 p->oflags |= VPO_WANTED; 1411 msleep(p, VM_OBJECT_MTX(backing_object), 1412 PDROP | PVM, "vmocol", 0); 1413 VM_OBJECT_LOCK(object); 1414 VM_OBJECT_LOCK(backing_object); 1415 /* 1416 * If we slept, anything could have 1417 * happened. Since the object is 1418 * marked dead, the backing offset 1419 * should not have changed so we 1420 * just restart our scan. 1421 */ 1422 p = TAILQ_FIRST(&backing_object->memq); 1423 continue; 1424 } 1425 } 1426 1427 KASSERT( 1428 p->object == backing_object, 1429 ("vm_object_backing_scan: object mismatch") 1430 ); 1431 1432 /* 1433 * Destroy any associated swap 1434 */ 1435 if (backing_object->type == OBJT_SWAP) { 1436 swap_pager_freespace( 1437 backing_object, 1438 p->pindex, 1439 1 1440 ); 1441 } 1442 1443 if ( 1444 p->pindex < backing_offset_index || 1445 new_pindex >= object->size 1446 ) { 1447 /* 1448 * Page is out of the parent object's range, we 1449 * can simply destroy it. 1450 */ 1451 vm_page_lock(p); 1452 KASSERT(!pmap_page_is_mapped(p), 1453 ("freeing mapped page %p", p)); 1454 if (p->wire_count == 0) 1455 vm_page_free(p); 1456 else 1457 vm_page_remove(p); 1458 vm_page_unlock(p); 1459 p = next; 1460 continue; 1461 } 1462 1463 pp = vm_page_lookup(object, new_pindex); 1464 if ( 1465 pp != NULL || 1466 vm_pager_has_page(object, new_pindex, NULL, NULL) 1467 ) { 1468 /* 1469 * page already exists in parent OR swap exists 1470 * for this location in the parent. Destroy 1471 * the original page from the backing object. 1472 * 1473 * Leave the parent's page alone 1474 */ 1475 vm_page_lock(p); 1476 KASSERT(!pmap_page_is_mapped(p), 1477 ("freeing mapped page %p", p)); 1478 if (p->wire_count == 0) 1479 vm_page_free(p); 1480 else 1481 vm_page_remove(p); 1482 vm_page_unlock(p); 1483 p = next; 1484 continue; 1485 } 1486 1487 #if VM_NRESERVLEVEL > 0 1488 /* 1489 * Rename the reservation. 1490 */ 1491 vm_reserv_rename(p, object, backing_object, 1492 backing_offset_index); 1493 #endif 1494 1495 /* 1496 * Page does not exist in parent, rename the 1497 * page from the backing object to the main object. 1498 * 1499 * If the page was mapped to a process, it can remain 1500 * mapped through the rename. 1501 */ 1502 vm_page_lock(p); 1503 vm_page_rename(p, object, new_pindex); 1504 vm_page_unlock(p); 1505 /* page automatically made dirty by rename */ 1506 } 1507 p = next; 1508 } 1509 return (r); 1510 } 1511 1512 1513 /* 1514 * this version of collapse allows the operation to occur earlier and 1515 * when paging_in_progress is true for an object... This is not a complete 1516 * operation, but should plug 99.9% of the rest of the leaks. 1517 */ 1518 static void 1519 vm_object_qcollapse(vm_object_t object) 1520 { 1521 vm_object_t backing_object = object->backing_object; 1522 1523 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1524 VM_OBJECT_LOCK_ASSERT(backing_object, MA_OWNED); 1525 1526 if (backing_object->ref_count != 1) 1527 return; 1528 1529 vm_object_backing_scan(object, OBSC_COLLAPSE_NOWAIT); 1530 } 1531 1532 /* 1533 * vm_object_collapse: 1534 * 1535 * Collapse an object with the object backing it. 1536 * Pages in the backing object are moved into the 1537 * parent, and the backing object is deallocated. 1538 */ 1539 void 1540 vm_object_collapse(vm_object_t object) 1541 { 1542 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1543 1544 while (TRUE) { 1545 vm_object_t backing_object; 1546 1547 /* 1548 * Verify that the conditions are right for collapse: 1549 * 1550 * The object exists and the backing object exists. 1551 */ 1552 if ((backing_object = object->backing_object) == NULL) 1553 break; 1554 1555 /* 1556 * we check the backing object first, because it is most likely 1557 * not collapsable. 1558 */ 1559 VM_OBJECT_LOCK(backing_object); 1560 if (backing_object->handle != NULL || 1561 (backing_object->type != OBJT_DEFAULT && 1562 backing_object->type != OBJT_SWAP) || 1563 (backing_object->flags & OBJ_DEAD) || 1564 object->handle != NULL || 1565 (object->type != OBJT_DEFAULT && 1566 object->type != OBJT_SWAP) || 1567 (object->flags & OBJ_DEAD)) { 1568 VM_OBJECT_UNLOCK(backing_object); 1569 break; 1570 } 1571 1572 if ( 1573 object->paging_in_progress != 0 || 1574 backing_object->paging_in_progress != 0 1575 ) { 1576 vm_object_qcollapse(object); 1577 VM_OBJECT_UNLOCK(backing_object); 1578 break; 1579 } 1580 /* 1581 * We know that we can either collapse the backing object (if 1582 * the parent is the only reference to it) or (perhaps) have 1583 * the parent bypass the object if the parent happens to shadow 1584 * all the resident pages in the entire backing object. 1585 * 1586 * This is ignoring pager-backed pages such as swap pages. 1587 * vm_object_backing_scan fails the shadowing test in this 1588 * case. 1589 */ 1590 if (backing_object->ref_count == 1) { 1591 /* 1592 * If there is exactly one reference to the backing 1593 * object, we can collapse it into the parent. 1594 */ 1595 vm_object_backing_scan(object, OBSC_COLLAPSE_WAIT); 1596 1597 #if VM_NRESERVLEVEL > 0 1598 /* 1599 * Break any reservations from backing_object. 1600 */ 1601 if (__predict_false(!LIST_EMPTY(&backing_object->rvq))) 1602 vm_reserv_break_all(backing_object); 1603 #endif 1604 1605 /* 1606 * Move the pager from backing_object to object. 1607 */ 1608 if (backing_object->type == OBJT_SWAP) { 1609 /* 1610 * swap_pager_copy() can sleep, in which case 1611 * the backing_object's and object's locks are 1612 * released and reacquired. 1613 */ 1614 swap_pager_copy( 1615 backing_object, 1616 object, 1617 OFF_TO_IDX(object->backing_object_offset), TRUE); 1618 1619 /* 1620 * Free any cached pages from backing_object. 1621 */ 1622 if (__predict_false(backing_object->cache != NULL)) 1623 vm_page_cache_free(backing_object, 0, 0); 1624 } 1625 /* 1626 * Object now shadows whatever backing_object did. 1627 * Note that the reference to 1628 * backing_object->backing_object moves from within 1629 * backing_object to within object. 1630 */ 1631 LIST_REMOVE(object, shadow_list); 1632 backing_object->shadow_count--; 1633 if (backing_object->backing_object) { 1634 VM_OBJECT_LOCK(backing_object->backing_object); 1635 LIST_REMOVE(backing_object, shadow_list); 1636 LIST_INSERT_HEAD( 1637 &backing_object->backing_object->shadow_head, 1638 object, shadow_list); 1639 /* 1640 * The shadow_count has not changed. 1641 */ 1642 VM_OBJECT_UNLOCK(backing_object->backing_object); 1643 } 1644 object->backing_object = backing_object->backing_object; 1645 object->backing_object_offset += 1646 backing_object->backing_object_offset; 1647 1648 /* 1649 * Discard backing_object. 1650 * 1651 * Since the backing object has no pages, no pager left, 1652 * and no object references within it, all that is 1653 * necessary is to dispose of it. 1654 */ 1655 KASSERT(backing_object->ref_count == 1, ( 1656 "backing_object %p was somehow re-referenced during collapse!", 1657 backing_object)); 1658 VM_OBJECT_UNLOCK(backing_object); 1659 vm_object_destroy(backing_object); 1660 1661 object_collapses++; 1662 } else { 1663 vm_object_t new_backing_object; 1664 1665 /* 1666 * If we do not entirely shadow the backing object, 1667 * there is nothing we can do so we give up. 1668 */ 1669 if (object->resident_page_count != object->size && 1670 vm_object_backing_scan(object, 1671 OBSC_TEST_ALL_SHADOWED) == 0) { 1672 VM_OBJECT_UNLOCK(backing_object); 1673 break; 1674 } 1675 1676 /* 1677 * Make the parent shadow the next object in the 1678 * chain. Deallocating backing_object will not remove 1679 * it, since its reference count is at least 2. 1680 */ 1681 LIST_REMOVE(object, shadow_list); 1682 backing_object->shadow_count--; 1683 1684 new_backing_object = backing_object->backing_object; 1685 if ((object->backing_object = new_backing_object) != NULL) { 1686 VM_OBJECT_LOCK(new_backing_object); 1687 LIST_INSERT_HEAD( 1688 &new_backing_object->shadow_head, 1689 object, 1690 shadow_list 1691 ); 1692 new_backing_object->shadow_count++; 1693 vm_object_reference_locked(new_backing_object); 1694 VM_OBJECT_UNLOCK(new_backing_object); 1695 object->backing_object_offset += 1696 backing_object->backing_object_offset; 1697 } 1698 1699 /* 1700 * Drop the reference count on backing_object. Since 1701 * its ref_count was at least 2, it will not vanish. 1702 */ 1703 backing_object->ref_count--; 1704 VM_OBJECT_UNLOCK(backing_object); 1705 object_bypasses++; 1706 } 1707 1708 /* 1709 * Try again with this object's new backing object. 1710 */ 1711 } 1712 } 1713 1714 /* 1715 * vm_object_page_remove: 1716 * 1717 * For the given object, either frees or invalidates each of the 1718 * specified pages. In general, a page is freed. However, if a 1719 * page is wired for any reason other than the existence of a 1720 * managed, wired mapping, then it may be invalidated but not 1721 * removed from the object. Pages are specified by the given 1722 * range ["start", "end") and Boolean "clean_only". As a 1723 * special case, if "end" is zero, then the range extends from 1724 * "start" to the end of the object. If "clean_only" is TRUE, 1725 * then only the non-dirty pages within the specified range are 1726 * affected. 1727 * 1728 * In general, this operation should only be performed on objects 1729 * that contain managed pages. There are two exceptions. First, 1730 * it may be performed on the kernel and kmem objects. Second, 1731 * it may be used by msync(..., MS_INVALIDATE) to invalidate 1732 * device-backed pages. In both of these cases, "clean_only" 1733 * must be FALSE. 1734 * 1735 * The object must be locked. 1736 */ 1737 void 1738 vm_object_page_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end, 1739 boolean_t clean_only) 1740 { 1741 vm_page_t p, next; 1742 int wirings; 1743 1744 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1745 if (object->resident_page_count == 0) 1746 goto skipmemq; 1747 1748 /* 1749 * Since physically-backed objects do not use managed pages, we can't 1750 * remove pages from the object (we must instead remove the page 1751 * references, and then destroy the object). 1752 */ 1753 KASSERT(object->type != OBJT_PHYS || object == kernel_object || 1754 object == kmem_object, 1755 ("attempt to remove pages from a physical object")); 1756 1757 vm_object_pip_add(object, 1); 1758 again: 1759 p = vm_page_find_least(object, start); 1760 1761 /* 1762 * Assert: the variable p is either (1) the page with the 1763 * least pindex greater than or equal to the parameter pindex 1764 * or (2) NULL. 1765 */ 1766 for (; 1767 p != NULL && (p->pindex < end || end == 0); 1768 p = next) { 1769 next = TAILQ_NEXT(p, listq); 1770 1771 /* 1772 * If the page is wired for any reason besides the 1773 * existence of managed, wired mappings, then it cannot 1774 * be freed. For example, fictitious pages, which 1775 * represent device memory, are inherently wired and 1776 * cannot be freed. They can, however, be invalidated 1777 * if "clean_only" is FALSE. 1778 */ 1779 vm_page_lock(p); 1780 if ((wirings = p->wire_count) != 0 && 1781 (wirings = pmap_page_wired_mappings(p)) != p->wire_count) { 1782 /* Fictitious pages do not have managed mappings. */ 1783 if ((p->flags & PG_FICTITIOUS) == 0) 1784 pmap_remove_all(p); 1785 /* Account for removal of managed, wired mappings. */ 1786 p->wire_count -= wirings; 1787 if (!clean_only) { 1788 p->valid = 0; 1789 vm_page_undirty(p); 1790 } 1791 vm_page_unlock(p); 1792 continue; 1793 } 1794 if (vm_page_sleep_if_busy(p, TRUE, "vmopar")) 1795 goto again; 1796 KASSERT((p->flags & PG_FICTITIOUS) == 0, 1797 ("vm_object_page_remove: page %p is fictitious", p)); 1798 if (clean_only && p->valid) { 1799 pmap_remove_write(p); 1800 if (p->dirty) { 1801 vm_page_unlock(p); 1802 continue; 1803 } 1804 } 1805 pmap_remove_all(p); 1806 /* Account for removal of managed, wired mappings. */ 1807 if (wirings != 0) 1808 p->wire_count -= wirings; 1809 vm_page_free(p); 1810 vm_page_unlock(p); 1811 } 1812 vm_object_pip_wakeup(object); 1813 skipmemq: 1814 if (__predict_false(object->cache != NULL)) 1815 vm_page_cache_free(object, start, end); 1816 } 1817 1818 /* 1819 * Populate the specified range of the object with valid pages. Returns 1820 * TRUE if the range is successfully populated and FALSE otherwise. 1821 * 1822 * Note: This function should be optimized to pass a larger array of 1823 * pages to vm_pager_get_pages() before it is applied to a non- 1824 * OBJT_DEVICE object. 1825 * 1826 * The object must be locked. 1827 */ 1828 boolean_t 1829 vm_object_populate(vm_object_t object, vm_pindex_t start, vm_pindex_t end) 1830 { 1831 vm_page_t m, ma[1]; 1832 vm_pindex_t pindex; 1833 int rv; 1834 1835 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1836 for (pindex = start; pindex < end; pindex++) { 1837 m = vm_page_grab(object, pindex, VM_ALLOC_NORMAL | 1838 VM_ALLOC_RETRY); 1839 if (m->valid != VM_PAGE_BITS_ALL) { 1840 ma[0] = m; 1841 rv = vm_pager_get_pages(object, ma, 1, 0); 1842 m = vm_page_lookup(object, pindex); 1843 if (m == NULL) 1844 break; 1845 if (rv != VM_PAGER_OK) { 1846 vm_page_lock(m); 1847 vm_page_free(m); 1848 vm_page_unlock(m); 1849 break; 1850 } 1851 } 1852 /* 1853 * Keep "m" busy because a subsequent iteration may unlock 1854 * the object. 1855 */ 1856 } 1857 if (pindex > start) { 1858 m = vm_page_lookup(object, start); 1859 while (m != NULL && m->pindex < pindex) { 1860 vm_page_wakeup(m); 1861 m = TAILQ_NEXT(m, listq); 1862 } 1863 } 1864 return (pindex == end); 1865 } 1866 1867 /* 1868 * Routine: vm_object_coalesce 1869 * Function: Coalesces two objects backing up adjoining 1870 * regions of memory into a single object. 1871 * 1872 * returns TRUE if objects were combined. 1873 * 1874 * NOTE: Only works at the moment if the second object is NULL - 1875 * if it's not, which object do we lock first? 1876 * 1877 * Parameters: 1878 * prev_object First object to coalesce 1879 * prev_offset Offset into prev_object 1880 * prev_size Size of reference to prev_object 1881 * next_size Size of reference to the second object 1882 * reserved Indicator that extension region has 1883 * swap accounted for 1884 * 1885 * Conditions: 1886 * The object must *not* be locked. 1887 */ 1888 boolean_t 1889 vm_object_coalesce(vm_object_t prev_object, vm_ooffset_t prev_offset, 1890 vm_size_t prev_size, vm_size_t next_size, boolean_t reserved) 1891 { 1892 vm_pindex_t next_pindex; 1893 1894 if (prev_object == NULL) 1895 return (TRUE); 1896 VM_OBJECT_LOCK(prev_object); 1897 if (prev_object->type != OBJT_DEFAULT && 1898 prev_object->type != OBJT_SWAP) { 1899 VM_OBJECT_UNLOCK(prev_object); 1900 return (FALSE); 1901 } 1902 1903 /* 1904 * Try to collapse the object first 1905 */ 1906 vm_object_collapse(prev_object); 1907 1908 /* 1909 * Can't coalesce if: . more than one reference . paged out . shadows 1910 * another object . has a copy elsewhere (any of which mean that the 1911 * pages not mapped to prev_entry may be in use anyway) 1912 */ 1913 if (prev_object->backing_object != NULL) { 1914 VM_OBJECT_UNLOCK(prev_object); 1915 return (FALSE); 1916 } 1917 1918 prev_size >>= PAGE_SHIFT; 1919 next_size >>= PAGE_SHIFT; 1920 next_pindex = OFF_TO_IDX(prev_offset) + prev_size; 1921 1922 if ((prev_object->ref_count > 1) && 1923 (prev_object->size != next_pindex)) { 1924 VM_OBJECT_UNLOCK(prev_object); 1925 return (FALSE); 1926 } 1927 1928 /* 1929 * Account for the charge. 1930 */ 1931 if (prev_object->cred != NULL) { 1932 1933 /* 1934 * If prev_object was charged, then this mapping, 1935 * althought not charged now, may become writable 1936 * later. Non-NULL cred in the object would prevent 1937 * swap reservation during enabling of the write 1938 * access, so reserve swap now. Failed reservation 1939 * cause allocation of the separate object for the map 1940 * entry, and swap reservation for this entry is 1941 * managed in appropriate time. 1942 */ 1943 if (!reserved && !swap_reserve_by_cred(ptoa(next_size), 1944 prev_object->cred)) { 1945 return (FALSE); 1946 } 1947 prev_object->charge += ptoa(next_size); 1948 } 1949 1950 /* 1951 * Remove any pages that may still be in the object from a previous 1952 * deallocation. 1953 */ 1954 if (next_pindex < prev_object->size) { 1955 vm_object_page_remove(prev_object, 1956 next_pindex, 1957 next_pindex + next_size, FALSE); 1958 if (prev_object->type == OBJT_SWAP) 1959 swap_pager_freespace(prev_object, 1960 next_pindex, next_size); 1961 #if 0 1962 if (prev_object->cred != NULL) { 1963 KASSERT(prev_object->charge >= 1964 ptoa(prev_object->size - next_pindex), 1965 ("object %p overcharged 1 %jx %jx", prev_object, 1966 (uintmax_t)next_pindex, (uintmax_t)next_size)); 1967 prev_object->charge -= ptoa(prev_object->size - 1968 next_pindex); 1969 } 1970 #endif 1971 } 1972 1973 /* 1974 * Extend the object if necessary. 1975 */ 1976 if (next_pindex + next_size > prev_object->size) 1977 prev_object->size = next_pindex + next_size; 1978 1979 VM_OBJECT_UNLOCK(prev_object); 1980 return (TRUE); 1981 } 1982 1983 void 1984 vm_object_set_writeable_dirty(vm_object_t object) 1985 { 1986 1987 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1988 if (object->type != OBJT_VNODE || 1989 (object->flags & OBJ_MIGHTBEDIRTY) != 0) 1990 return; 1991 vm_object_set_flag(object, OBJ_MIGHTBEDIRTY); 1992 } 1993 1994 #include "opt_ddb.h" 1995 #ifdef DDB 1996 #include <sys/kernel.h> 1997 1998 #include <sys/cons.h> 1999 2000 #include <ddb/ddb.h> 2001 2002 static int 2003 _vm_object_in_map(vm_map_t map, vm_object_t object, vm_map_entry_t entry) 2004 { 2005 vm_map_t tmpm; 2006 vm_map_entry_t tmpe; 2007 vm_object_t obj; 2008 int entcount; 2009 2010 if (map == 0) 2011 return 0; 2012 2013 if (entry == 0) { 2014 tmpe = map->header.next; 2015 entcount = map->nentries; 2016 while (entcount-- && (tmpe != &map->header)) { 2017 if (_vm_object_in_map(map, object, tmpe)) { 2018 return 1; 2019 } 2020 tmpe = tmpe->next; 2021 } 2022 } else if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) { 2023 tmpm = entry->object.sub_map; 2024 tmpe = tmpm->header.next; 2025 entcount = tmpm->nentries; 2026 while (entcount-- && tmpe != &tmpm->header) { 2027 if (_vm_object_in_map(tmpm, object, tmpe)) { 2028 return 1; 2029 } 2030 tmpe = tmpe->next; 2031 } 2032 } else if ((obj = entry->object.vm_object) != NULL) { 2033 for (; obj; obj = obj->backing_object) 2034 if (obj == object) { 2035 return 1; 2036 } 2037 } 2038 return 0; 2039 } 2040 2041 static int 2042 vm_object_in_map(vm_object_t object) 2043 { 2044 struct proc *p; 2045 2046 /* sx_slock(&allproc_lock); */ 2047 FOREACH_PROC_IN_SYSTEM(p) { 2048 if (!p->p_vmspace /* || (p->p_flag & (P_SYSTEM|P_WEXIT)) */) 2049 continue; 2050 if (_vm_object_in_map(&p->p_vmspace->vm_map, object, 0)) { 2051 /* sx_sunlock(&allproc_lock); */ 2052 return 1; 2053 } 2054 } 2055 /* sx_sunlock(&allproc_lock); */ 2056 if (_vm_object_in_map(kernel_map, object, 0)) 2057 return 1; 2058 if (_vm_object_in_map(kmem_map, object, 0)) 2059 return 1; 2060 if (_vm_object_in_map(pager_map, object, 0)) 2061 return 1; 2062 if (_vm_object_in_map(buffer_map, object, 0)) 2063 return 1; 2064 return 0; 2065 } 2066 2067 DB_SHOW_COMMAND(vmochk, vm_object_check) 2068 { 2069 vm_object_t object; 2070 2071 /* 2072 * make sure that internal objs are in a map somewhere 2073 * and none have zero ref counts. 2074 */ 2075 TAILQ_FOREACH(object, &vm_object_list, object_list) { 2076 if (object->handle == NULL && 2077 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) { 2078 if (object->ref_count == 0) { 2079 db_printf("vmochk: internal obj has zero ref count: %ld\n", 2080 (long)object->size); 2081 } 2082 if (!vm_object_in_map(object)) { 2083 db_printf( 2084 "vmochk: internal obj is not in a map: " 2085 "ref: %d, size: %lu: 0x%lx, backing_object: %p\n", 2086 object->ref_count, (u_long)object->size, 2087 (u_long)object->size, 2088 (void *)object->backing_object); 2089 } 2090 } 2091 } 2092 } 2093 2094 /* 2095 * vm_object_print: [ debug ] 2096 */ 2097 DB_SHOW_COMMAND(object, vm_object_print_static) 2098 { 2099 /* XXX convert args. */ 2100 vm_object_t object = (vm_object_t)addr; 2101 boolean_t full = have_addr; 2102 2103 vm_page_t p; 2104 2105 /* XXX count is an (unused) arg. Avoid shadowing it. */ 2106 #define count was_count 2107 2108 int count; 2109 2110 if (object == NULL) 2111 return; 2112 2113 db_iprintf( 2114 "Object %p: type=%d, size=0x%jx, res=%d, ref=%d, flags=0x%x ruid %d charge %jx\n", 2115 object, (int)object->type, (uintmax_t)object->size, 2116 object->resident_page_count, object->ref_count, object->flags, 2117 object->cred ? object->cred->cr_ruid : -1, (uintmax_t)object->charge); 2118 db_iprintf(" sref=%d, backing_object(%d)=(%p)+0x%jx\n", 2119 object->shadow_count, 2120 object->backing_object ? object->backing_object->ref_count : 0, 2121 object->backing_object, (uintmax_t)object->backing_object_offset); 2122 2123 if (!full) 2124 return; 2125 2126 db_indent += 2; 2127 count = 0; 2128 TAILQ_FOREACH(p, &object->memq, listq) { 2129 if (count == 0) 2130 db_iprintf("memory:="); 2131 else if (count == 6) { 2132 db_printf("\n"); 2133 db_iprintf(" ..."); 2134 count = 0; 2135 } else 2136 db_printf(","); 2137 count++; 2138 2139 db_printf("(off=0x%jx,page=0x%jx)", 2140 (uintmax_t)p->pindex, (uintmax_t)VM_PAGE_TO_PHYS(p)); 2141 } 2142 if (count != 0) 2143 db_printf("\n"); 2144 db_indent -= 2; 2145 } 2146 2147 /* XXX. */ 2148 #undef count 2149 2150 /* XXX need this non-static entry for calling from vm_map_print. */ 2151 void 2152 vm_object_print( 2153 /* db_expr_t */ long addr, 2154 boolean_t have_addr, 2155 /* db_expr_t */ long count, 2156 char *modif) 2157 { 2158 vm_object_print_static(addr, have_addr, count, modif); 2159 } 2160 2161 DB_SHOW_COMMAND(vmopag, vm_object_print_pages) 2162 { 2163 vm_object_t object; 2164 vm_pindex_t fidx; 2165 vm_paddr_t pa; 2166 vm_page_t m, prev_m; 2167 int rcount, nl, c; 2168 2169 nl = 0; 2170 TAILQ_FOREACH(object, &vm_object_list, object_list) { 2171 db_printf("new object: %p\n", (void *)object); 2172 if (nl > 18) { 2173 c = cngetc(); 2174 if (c != ' ') 2175 return; 2176 nl = 0; 2177 } 2178 nl++; 2179 rcount = 0; 2180 fidx = 0; 2181 pa = -1; 2182 TAILQ_FOREACH(m, &object->memq, listq) { 2183 if (m->pindex > 128) 2184 break; 2185 if ((prev_m = TAILQ_PREV(m, pglist, listq)) != NULL && 2186 prev_m->pindex + 1 != m->pindex) { 2187 if (rcount) { 2188 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2189 (long)fidx, rcount, (long)pa); 2190 if (nl > 18) { 2191 c = cngetc(); 2192 if (c != ' ') 2193 return; 2194 nl = 0; 2195 } 2196 nl++; 2197 rcount = 0; 2198 } 2199 } 2200 if (rcount && 2201 (VM_PAGE_TO_PHYS(m) == pa + rcount * PAGE_SIZE)) { 2202 ++rcount; 2203 continue; 2204 } 2205 if (rcount) { 2206 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2207 (long)fidx, rcount, (long)pa); 2208 if (nl > 18) { 2209 c = cngetc(); 2210 if (c != ' ') 2211 return; 2212 nl = 0; 2213 } 2214 nl++; 2215 } 2216 fidx = m->pindex; 2217 pa = VM_PAGE_TO_PHYS(m); 2218 rcount = 1; 2219 } 2220 if (rcount) { 2221 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2222 (long)fidx, rcount, (long)pa); 2223 if (nl > 18) { 2224 c = cngetc(); 2225 if (c != ' ') 2226 return; 2227 nl = 0; 2228 } 2229 nl++; 2230 } 2231 } 2232 } 2233 #endif /* DDB */ 2234