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, int flags, int *clearobjflags); 105 static boolean_t vm_object_page_remove_write(vm_page_t p, int flags, 106 int *clearobjflags); 107 static void vm_object_qcollapse(vm_object_t object); 108 static void vm_object_vndeallocate(vm_object_t object); 109 110 /* 111 * Virtual memory objects maintain the actual data 112 * associated with allocated virtual memory. A given 113 * page of memory exists within exactly one object. 114 * 115 * An object is only deallocated when all "references" 116 * are given up. Only one "reference" to a given 117 * region of an object should be writeable. 118 * 119 * Associated with each object is a list of all resident 120 * memory pages belonging to that object; this list is 121 * maintained by the "vm_page" module, and locked by the object's 122 * lock. 123 * 124 * Each object also records a "pager" routine which is 125 * used to retrieve (and store) pages to the proper backing 126 * storage. In addition, objects may be backed by other 127 * objects from which they were virtual-copied. 128 * 129 * The only items within the object structure which are 130 * modified after time of creation are: 131 * reference count locked by object's lock 132 * pager routine locked by object's lock 133 * 134 */ 135 136 struct object_q vm_object_list; 137 struct mtx vm_object_list_mtx; /* lock for object list and count */ 138 139 struct vm_object kernel_object_store; 140 struct vm_object kmem_object_store; 141 142 SYSCTL_NODE(_vm_stats, OID_AUTO, object, CTLFLAG_RD, 0, "VM object stats"); 143 144 static long object_collapses; 145 SYSCTL_LONG(_vm_stats_object, OID_AUTO, collapses, CTLFLAG_RD, 146 &object_collapses, 0, "VM object collapses"); 147 148 static long object_bypasses; 149 SYSCTL_LONG(_vm_stats_object, OID_AUTO, bypasses, CTLFLAG_RD, 150 &object_bypasses, 0, "VM object bypasses"); 151 152 static uma_zone_t obj_zone; 153 154 static int vm_object_zinit(void *mem, int size, int flags); 155 156 #ifdef INVARIANTS 157 static void vm_object_zdtor(void *mem, int size, void *arg); 158 159 static void 160 vm_object_zdtor(void *mem, int size, void *arg) 161 { 162 vm_object_t object; 163 164 object = (vm_object_t)mem; 165 KASSERT(TAILQ_EMPTY(&object->memq), 166 ("object %p has resident pages", 167 object)); 168 #if VM_NRESERVLEVEL > 0 169 KASSERT(LIST_EMPTY(&object->rvq), 170 ("object %p has reservations", 171 object)); 172 #endif 173 KASSERT(object->cache == NULL, 174 ("object %p has cached pages", 175 object)); 176 KASSERT(object->paging_in_progress == 0, 177 ("object %p paging_in_progress = %d", 178 object, object->paging_in_progress)); 179 KASSERT(object->resident_page_count == 0, 180 ("object %p resident_page_count = %d", 181 object, object->resident_page_count)); 182 KASSERT(object->shadow_count == 0, 183 ("object %p shadow_count = %d", 184 object, object->shadow_count)); 185 } 186 #endif 187 188 static int 189 vm_object_zinit(void *mem, int size, int flags) 190 { 191 vm_object_t object; 192 193 object = (vm_object_t)mem; 194 bzero(&object->mtx, sizeof(object->mtx)); 195 VM_OBJECT_LOCK_INIT(object, "standard object"); 196 197 /* These are true for any object that has been freed */ 198 object->paging_in_progress = 0; 199 object->resident_page_count = 0; 200 object->shadow_count = 0; 201 return (0); 202 } 203 204 void 205 _vm_object_allocate(objtype_t type, vm_pindex_t size, vm_object_t object) 206 { 207 208 TAILQ_INIT(&object->memq); 209 LIST_INIT(&object->shadow_head); 210 211 object->root = NULL; 212 object->type = type; 213 object->size = size; 214 object->generation = 1; 215 object->ref_count = 1; 216 object->memattr = VM_MEMATTR_DEFAULT; 217 object->flags = 0; 218 object->cred = NULL; 219 object->charge = 0; 220 if ((object->type == OBJT_DEFAULT) || (object->type == OBJT_SWAP)) 221 object->flags = OBJ_ONEMAPPING; 222 object->pg_color = 0; 223 object->handle = NULL; 224 object->backing_object = NULL; 225 object->backing_object_offset = (vm_ooffset_t) 0; 226 #if VM_NRESERVLEVEL > 0 227 LIST_INIT(&object->rvq); 228 #endif 229 object->cache = NULL; 230 231 mtx_lock(&vm_object_list_mtx); 232 TAILQ_INSERT_TAIL(&vm_object_list, object, object_list); 233 mtx_unlock(&vm_object_list_mtx); 234 } 235 236 /* 237 * vm_object_init: 238 * 239 * Initialize the VM objects module. 240 */ 241 void 242 vm_object_init(void) 243 { 244 TAILQ_INIT(&vm_object_list); 245 mtx_init(&vm_object_list_mtx, "vm object_list", NULL, MTX_DEF); 246 247 VM_OBJECT_LOCK_INIT(kernel_object, "kernel object"); 248 _vm_object_allocate(OBJT_PHYS, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS), 249 kernel_object); 250 #if VM_NRESERVLEVEL > 0 251 kernel_object->flags |= OBJ_COLORED; 252 kernel_object->pg_color = (u_short)atop(VM_MIN_KERNEL_ADDRESS); 253 #endif 254 255 VM_OBJECT_LOCK_INIT(kmem_object, "kmem object"); 256 _vm_object_allocate(OBJT_PHYS, OFF_TO_IDX(VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS), 257 kmem_object); 258 #if VM_NRESERVLEVEL > 0 259 kmem_object->flags |= OBJ_COLORED; 260 kmem_object->pg_color = (u_short)atop(VM_MIN_KERNEL_ADDRESS); 261 #endif 262 263 /* 264 * The lock portion of struct vm_object must be type stable due 265 * to vm_pageout_fallback_object_lock locking a vm object 266 * without holding any references to it. 267 */ 268 obj_zone = uma_zcreate("VM OBJECT", sizeof (struct vm_object), NULL, 269 #ifdef INVARIANTS 270 vm_object_zdtor, 271 #else 272 NULL, 273 #endif 274 vm_object_zinit, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM|UMA_ZONE_NOFREE); 275 } 276 277 void 278 vm_object_clear_flag(vm_object_t object, u_short bits) 279 { 280 281 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 282 object->flags &= ~bits; 283 } 284 285 /* 286 * Sets the default memory attribute for the specified object. Pages 287 * that are allocated to this object are by default assigned this memory 288 * attribute. 289 * 290 * Presently, this function must be called before any pages are allocated 291 * to the object. In the future, this requirement may be relaxed for 292 * "default" and "swap" objects. 293 */ 294 int 295 vm_object_set_memattr(vm_object_t object, vm_memattr_t memattr) 296 { 297 298 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 299 switch (object->type) { 300 case OBJT_DEFAULT: 301 case OBJT_DEVICE: 302 case OBJT_PHYS: 303 case OBJT_SG: 304 case OBJT_SWAP: 305 case OBJT_VNODE: 306 if (!TAILQ_EMPTY(&object->memq)) 307 return (KERN_FAILURE); 308 break; 309 case OBJT_DEAD: 310 return (KERN_INVALID_ARGUMENT); 311 } 312 object->memattr = memattr; 313 return (KERN_SUCCESS); 314 } 315 316 void 317 vm_object_pip_add(vm_object_t object, short i) 318 { 319 320 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 321 object->paging_in_progress += i; 322 } 323 324 void 325 vm_object_pip_subtract(vm_object_t object, short i) 326 { 327 328 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 329 object->paging_in_progress -= i; 330 } 331 332 void 333 vm_object_pip_wakeup(vm_object_t object) 334 { 335 336 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 337 object->paging_in_progress--; 338 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) { 339 vm_object_clear_flag(object, OBJ_PIPWNT); 340 wakeup(object); 341 } 342 } 343 344 void 345 vm_object_pip_wakeupn(vm_object_t object, short i) 346 { 347 348 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 349 if (i) 350 object->paging_in_progress -= i; 351 if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) { 352 vm_object_clear_flag(object, OBJ_PIPWNT); 353 wakeup(object); 354 } 355 } 356 357 void 358 vm_object_pip_wait(vm_object_t object, char *waitid) 359 { 360 361 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 362 while (object->paging_in_progress) { 363 object->flags |= OBJ_PIPWNT; 364 msleep(object, VM_OBJECT_MTX(object), PVM, waitid, 0); 365 } 366 } 367 368 /* 369 * vm_object_allocate: 370 * 371 * Returns a new object with the given size. 372 */ 373 vm_object_t 374 vm_object_allocate(objtype_t type, vm_pindex_t size) 375 { 376 vm_object_t object; 377 378 object = (vm_object_t)uma_zalloc(obj_zone, M_WAITOK); 379 _vm_object_allocate(type, size, object); 380 return (object); 381 } 382 383 384 /* 385 * vm_object_reference: 386 * 387 * Gets another reference to the given object. Note: OBJ_DEAD 388 * objects can be referenced during final cleaning. 389 */ 390 void 391 vm_object_reference(vm_object_t object) 392 { 393 if (object == NULL) 394 return; 395 VM_OBJECT_LOCK(object); 396 vm_object_reference_locked(object); 397 VM_OBJECT_UNLOCK(object); 398 } 399 400 /* 401 * vm_object_reference_locked: 402 * 403 * Gets another reference to the given object. 404 * 405 * The object must be locked. 406 */ 407 void 408 vm_object_reference_locked(vm_object_t object) 409 { 410 struct vnode *vp; 411 412 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 413 object->ref_count++; 414 if (object->type == OBJT_VNODE) { 415 vp = object->handle; 416 vref(vp); 417 } 418 } 419 420 /* 421 * Handle deallocating an object of type OBJT_VNODE. 422 */ 423 static void 424 vm_object_vndeallocate(vm_object_t object) 425 { 426 struct vnode *vp = (struct vnode *) object->handle; 427 428 VFS_ASSERT_GIANT(vp->v_mount); 429 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 430 KASSERT(object->type == OBJT_VNODE, 431 ("vm_object_vndeallocate: not a vnode object")); 432 KASSERT(vp != NULL, ("vm_object_vndeallocate: missing vp")); 433 #ifdef INVARIANTS 434 if (object->ref_count == 0) { 435 vprint("vm_object_vndeallocate", vp); 436 panic("vm_object_vndeallocate: bad object reference count"); 437 } 438 #endif 439 440 if (object->ref_count > 1) { 441 object->ref_count--; 442 VM_OBJECT_UNLOCK(object); 443 /* vrele may need the vnode lock. */ 444 vrele(vp); 445 } else { 446 VM_OBJECT_UNLOCK(object); 447 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 448 VM_OBJECT_LOCK(object); 449 object->ref_count--; 450 if (object->ref_count == 0) 451 vp->v_vflag &= ~VV_TEXT; 452 VM_OBJECT_UNLOCK(object); 453 vput(vp); 454 } 455 } 456 457 /* 458 * vm_object_deallocate: 459 * 460 * Release a reference to the specified object, 461 * gained either through a vm_object_allocate 462 * or a vm_object_reference call. When all references 463 * are gone, storage associated with this object 464 * may be relinquished. 465 * 466 * No object may be locked. 467 */ 468 void 469 vm_object_deallocate(vm_object_t object) 470 { 471 vm_object_t temp; 472 473 while (object != NULL) { 474 int vfslocked; 475 476 vfslocked = 0; 477 restart: 478 VM_OBJECT_LOCK(object); 479 if (object->type == OBJT_VNODE) { 480 struct vnode *vp = (struct vnode *) object->handle; 481 482 /* 483 * Conditionally acquire Giant for a vnode-backed 484 * object. We have to be careful since the type of 485 * a vnode object can change while the object is 486 * unlocked. 487 */ 488 if (VFS_NEEDSGIANT(vp->v_mount) && !vfslocked) { 489 vfslocked = 1; 490 if (!mtx_trylock(&Giant)) { 491 VM_OBJECT_UNLOCK(object); 492 mtx_lock(&Giant); 493 goto restart; 494 } 495 } 496 vm_object_vndeallocate(object); 497 VFS_UNLOCK_GIANT(vfslocked); 498 return; 499 } else 500 /* 501 * This is to handle the case that the object 502 * changed type while we dropped its lock to 503 * obtain Giant. 504 */ 505 VFS_UNLOCK_GIANT(vfslocked); 506 507 KASSERT(object->ref_count != 0, 508 ("vm_object_deallocate: object deallocated too many times: %d", object->type)); 509 510 /* 511 * If the reference count goes to 0 we start calling 512 * vm_object_terminate() on the object chain. 513 * A ref count of 1 may be a special case depending on the 514 * shadow count being 0 or 1. 515 */ 516 object->ref_count--; 517 if (object->ref_count > 1) { 518 VM_OBJECT_UNLOCK(object); 519 return; 520 } else if (object->ref_count == 1) { 521 if (object->shadow_count == 0 && 522 object->handle == NULL && 523 (object->type == OBJT_DEFAULT || 524 object->type == OBJT_SWAP)) { 525 vm_object_set_flag(object, OBJ_ONEMAPPING); 526 } else if ((object->shadow_count == 1) && 527 (object->handle == NULL) && 528 (object->type == OBJT_DEFAULT || 529 object->type == OBJT_SWAP)) { 530 vm_object_t robject; 531 532 robject = LIST_FIRST(&object->shadow_head); 533 KASSERT(robject != NULL, 534 ("vm_object_deallocate: ref_count: %d, shadow_count: %d", 535 object->ref_count, 536 object->shadow_count)); 537 if (!VM_OBJECT_TRYLOCK(robject)) { 538 /* 539 * Avoid a potential deadlock. 540 */ 541 object->ref_count++; 542 VM_OBJECT_UNLOCK(object); 543 /* 544 * More likely than not the thread 545 * holding robject's lock has lower 546 * priority than the current thread. 547 * Let the lower priority thread run. 548 */ 549 pause("vmo_de", 1); 550 continue; 551 } 552 /* 553 * Collapse object into its shadow unless its 554 * shadow is dead. In that case, object will 555 * be deallocated by the thread that is 556 * deallocating its shadow. 557 */ 558 if ((robject->flags & OBJ_DEAD) == 0 && 559 (robject->handle == NULL) && 560 (robject->type == OBJT_DEFAULT || 561 robject->type == OBJT_SWAP)) { 562 563 robject->ref_count++; 564 retry: 565 if (robject->paging_in_progress) { 566 VM_OBJECT_UNLOCK(object); 567 vm_object_pip_wait(robject, 568 "objde1"); 569 temp = robject->backing_object; 570 if (object == temp) { 571 VM_OBJECT_LOCK(object); 572 goto retry; 573 } 574 } else if (object->paging_in_progress) { 575 VM_OBJECT_UNLOCK(robject); 576 object->flags |= OBJ_PIPWNT; 577 msleep(object, 578 VM_OBJECT_MTX(object), 579 PDROP | PVM, "objde2", 0); 580 VM_OBJECT_LOCK(robject); 581 temp = robject->backing_object; 582 if (object == temp) { 583 VM_OBJECT_LOCK(object); 584 goto retry; 585 } 586 } else 587 VM_OBJECT_UNLOCK(object); 588 589 if (robject->ref_count == 1) { 590 robject->ref_count--; 591 object = robject; 592 goto doterm; 593 } 594 object = robject; 595 vm_object_collapse(object); 596 VM_OBJECT_UNLOCK(object); 597 continue; 598 } 599 VM_OBJECT_UNLOCK(robject); 600 } 601 VM_OBJECT_UNLOCK(object); 602 return; 603 } 604 doterm: 605 temp = object->backing_object; 606 if (temp != NULL) { 607 VM_OBJECT_LOCK(temp); 608 LIST_REMOVE(object, shadow_list); 609 temp->shadow_count--; 610 VM_OBJECT_UNLOCK(temp); 611 object->backing_object = NULL; 612 } 613 /* 614 * Don't double-terminate, we could be in a termination 615 * recursion due to the terminate having to sync data 616 * to disk. 617 */ 618 if ((object->flags & OBJ_DEAD) == 0) 619 vm_object_terminate(object); 620 else 621 VM_OBJECT_UNLOCK(object); 622 object = temp; 623 } 624 } 625 626 /* 627 * vm_object_destroy removes the object from the global object list 628 * and frees the space for the object. 629 */ 630 void 631 vm_object_destroy(vm_object_t object) 632 { 633 634 /* 635 * Remove the object from the global object list. 636 */ 637 mtx_lock(&vm_object_list_mtx); 638 TAILQ_REMOVE(&vm_object_list, object, object_list); 639 mtx_unlock(&vm_object_list_mtx); 640 641 /* 642 * Release the allocation charge. 643 */ 644 if (object->cred != NULL) { 645 KASSERT(object->type == OBJT_DEFAULT || 646 object->type == OBJT_SWAP, 647 ("vm_object_terminate: non-swap obj %p has cred", 648 object)); 649 swap_release_by_cred(object->charge, object->cred); 650 object->charge = 0; 651 crfree(object->cred); 652 object->cred = NULL; 653 } 654 655 /* 656 * Free the space for the object. 657 */ 658 uma_zfree(obj_zone, object); 659 } 660 661 /* 662 * vm_object_terminate actually destroys the specified object, freeing 663 * up all previously used resources. 664 * 665 * The object must be locked. 666 * This routine may block. 667 */ 668 void 669 vm_object_terminate(vm_object_t object) 670 { 671 vm_page_t p, p_next; 672 673 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 674 675 /* 676 * Make sure no one uses us. 677 */ 678 vm_object_set_flag(object, OBJ_DEAD); 679 680 /* 681 * wait for the pageout daemon to be done with the object 682 */ 683 vm_object_pip_wait(object, "objtrm"); 684 685 KASSERT(!object->paging_in_progress, 686 ("vm_object_terminate: pageout in progress")); 687 688 /* 689 * Clean and free the pages, as appropriate. All references to the 690 * object are gone, so we don't need to lock it. 691 */ 692 if (object->type == OBJT_VNODE) { 693 struct vnode *vp = (struct vnode *)object->handle; 694 695 /* 696 * Clean pages and flush buffers. 697 */ 698 vm_object_page_clean(object, 0, 0, OBJPC_SYNC); 699 VM_OBJECT_UNLOCK(object); 700 701 vinvalbuf(vp, V_SAVE, 0, 0); 702 703 VM_OBJECT_LOCK(object); 704 } 705 706 KASSERT(object->ref_count == 0, 707 ("vm_object_terminate: object with references, ref_count=%d", 708 object->ref_count)); 709 710 /* 711 * Free any remaining pageable pages. This also removes them from the 712 * paging queues. However, don't free wired pages, just remove them 713 * from the object. Rather than incrementally removing each page from 714 * the object, the page and object are reset to any empty state. 715 */ 716 TAILQ_FOREACH_SAFE(p, &object->memq, listq, p_next) { 717 KASSERT(!p->busy && (p->oflags & VPO_BUSY) == 0, 718 ("vm_object_terminate: freeing busy page %p", p)); 719 vm_page_lock(p); 720 /* 721 * Optimize the page's removal from the object by resetting 722 * its "object" field. Specifically, if the page is not 723 * wired, then the effect of this assignment is that 724 * vm_page_free()'s call to vm_page_remove() will return 725 * immediately without modifying the page or the object. 726 */ 727 p->object = NULL; 728 if (p->wire_count == 0) { 729 vm_page_free(p); 730 PCPU_INC(cnt.v_pfree); 731 } 732 vm_page_unlock(p); 733 } 734 /* 735 * If the object contained any pages, then reset it to an empty state. 736 * None of the object's fields, including "resident_page_count", were 737 * modified by the preceding loop. 738 */ 739 if (object->resident_page_count != 0) { 740 object->root = NULL; 741 TAILQ_INIT(&object->memq); 742 object->resident_page_count = 0; 743 if (object->type == OBJT_VNODE) 744 vdrop(object->handle); 745 } 746 747 #if VM_NRESERVLEVEL > 0 748 if (__predict_false(!LIST_EMPTY(&object->rvq))) 749 vm_reserv_break_all(object); 750 #endif 751 if (__predict_false(object->cache != NULL)) 752 vm_page_cache_free(object, 0, 0); 753 754 /* 755 * Let the pager know object is dead. 756 */ 757 vm_pager_deallocate(object); 758 VM_OBJECT_UNLOCK(object); 759 760 vm_object_destroy(object); 761 } 762 763 /* 764 * Make the page read-only so that we can clear the object flags. However, if 765 * this is a nosync mmap then the object is likely to stay dirty so do not 766 * mess with the page and do not clear the object flags. Returns TRUE if the 767 * page should be flushed, and FALSE otherwise. 768 */ 769 static boolean_t 770 vm_object_page_remove_write(vm_page_t p, int flags, int *clearobjflags) 771 { 772 773 /* 774 * If we have been asked to skip nosync pages and this is a 775 * nosync page, skip it. Note that the object flags were not 776 * cleared in this case so we do not have to set them. 777 */ 778 if ((flags & OBJPC_NOSYNC) != 0 && (p->oflags & VPO_NOSYNC) != 0) { 779 *clearobjflags = 0; 780 return (FALSE); 781 } else { 782 pmap_remove_write(p); 783 return (p->dirty != 0); 784 } 785 } 786 787 /* 788 * vm_object_page_clean 789 * 790 * Clean all dirty pages in the specified range of object. Leaves page 791 * on whatever queue it is currently on. If NOSYNC is set then do not 792 * write out pages with VPO_NOSYNC set (originally comes from MAP_NOSYNC), 793 * leaving the object dirty. 794 * 795 * When stuffing pages asynchronously, allow clustering. XXX we need a 796 * synchronous clustering mode implementation. 797 * 798 * Odd semantics: if start == end, we clean everything. 799 * 800 * The object must be locked. 801 */ 802 void 803 vm_object_page_clean(vm_object_t object, vm_ooffset_t start, vm_ooffset_t end, 804 int flags) 805 { 806 vm_page_t np, p; 807 vm_pindex_t pi, tend, tstart; 808 int clearobjflags, curgeneration, n, pagerflags; 809 810 mtx_assert(&vm_page_queue_mtx, MA_NOTOWNED); 811 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 812 KASSERT(object->type == OBJT_VNODE, ("Not a vnode object")); 813 if ((object->flags & OBJ_MIGHTBEDIRTY) == 0 || 814 object->resident_page_count == 0) 815 return; 816 817 pagerflags = (flags & (OBJPC_SYNC | OBJPC_INVAL)) != 0 ? 818 VM_PAGER_PUT_SYNC : VM_PAGER_CLUSTER_OK; 819 pagerflags |= (flags & OBJPC_INVAL) != 0 ? VM_PAGER_PUT_INVAL : 0; 820 821 tstart = OFF_TO_IDX(start); 822 tend = (end == 0) ? object->size : OFF_TO_IDX(end + PAGE_MASK); 823 clearobjflags = tstart == 0 && tend >= object->size; 824 825 rescan: 826 curgeneration = object->generation; 827 828 for (p = vm_page_find_least(object, tstart); p != NULL; p = np) { 829 pi = p->pindex; 830 if (pi >= tend) 831 break; 832 np = TAILQ_NEXT(p, listq); 833 if (p->valid == 0) 834 continue; 835 if (vm_page_sleep_if_busy(p, TRUE, "vpcwai")) { 836 if (object->generation != curgeneration) 837 goto rescan; 838 np = vm_page_find_least(object, pi); 839 continue; 840 } 841 if (!vm_object_page_remove_write(p, flags, &clearobjflags)) 842 continue; 843 844 n = vm_object_page_collect_flush(object, p, pagerflags, 845 flags, &clearobjflags); 846 if (object->generation != curgeneration) 847 goto rescan; 848 np = vm_page_find_least(object, pi + n); 849 } 850 #if 0 851 VOP_FSYNC(vp, (pagerflags & VM_PAGER_PUT_SYNC) ? MNT_WAIT : 0); 852 #endif 853 854 if (clearobjflags) 855 vm_object_clear_flag(object, OBJ_MIGHTBEDIRTY); 856 } 857 858 static int 859 vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int pagerflags, 860 int flags, int *clearobjflags) 861 { 862 vm_page_t ma[vm_pageout_page_count], p_first, tp; 863 int count, i, mreq, runlen; 864 865 mtx_assert(&vm_page_queue_mtx, MA_NOTOWNED); 866 vm_page_lock_assert(p, MA_NOTOWNED); 867 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 868 869 count = 1; 870 mreq = 0; 871 872 for (tp = p; count < vm_pageout_page_count; count++) { 873 tp = vm_page_next(tp); 874 if (tp == NULL || tp->busy != 0 || (tp->oflags & VPO_BUSY) != 0) 875 break; 876 if (!vm_object_page_remove_write(tp, flags, clearobjflags)) 877 break; 878 } 879 880 for (p_first = p; count < vm_pageout_page_count; count++) { 881 tp = vm_page_prev(p_first); 882 if (tp == NULL || tp->busy != 0 || (tp->oflags & VPO_BUSY) != 0) 883 break; 884 if (!vm_object_page_remove_write(tp, flags, clearobjflags)) 885 break; 886 p_first = tp; 887 mreq++; 888 } 889 890 for (tp = p_first, i = 0; i < count; tp = TAILQ_NEXT(tp, listq), i++) 891 ma[i] = tp; 892 893 vm_pageout_flush(ma, count, pagerflags, mreq, &runlen); 894 return (runlen); 895 } 896 897 /* 898 * Note that there is absolutely no sense in writing out 899 * anonymous objects, so we track down the vnode object 900 * to write out. 901 * We invalidate (remove) all pages from the address space 902 * for semantic correctness. 903 * 904 * Note: certain anonymous maps, such as MAP_NOSYNC maps, 905 * may start out with a NULL object. 906 */ 907 void 908 vm_object_sync(vm_object_t object, vm_ooffset_t offset, vm_size_t size, 909 boolean_t syncio, boolean_t invalidate) 910 { 911 vm_object_t backing_object; 912 struct vnode *vp; 913 struct mount *mp; 914 int flags; 915 916 if (object == NULL) 917 return; 918 VM_OBJECT_LOCK(object); 919 while ((backing_object = object->backing_object) != NULL) { 920 VM_OBJECT_LOCK(backing_object); 921 offset += object->backing_object_offset; 922 VM_OBJECT_UNLOCK(object); 923 object = backing_object; 924 if (object->size < OFF_TO_IDX(offset + size)) 925 size = IDX_TO_OFF(object->size) - offset; 926 } 927 /* 928 * Flush pages if writing is allowed, invalidate them 929 * if invalidation requested. Pages undergoing I/O 930 * will be ignored by vm_object_page_remove(). 931 * 932 * We cannot lock the vnode and then wait for paging 933 * to complete without deadlocking against vm_fault. 934 * Instead we simply call vm_object_page_remove() and 935 * allow it to block internally on a page-by-page 936 * basis when it encounters pages undergoing async 937 * I/O. 938 */ 939 if (object->type == OBJT_VNODE && 940 (object->flags & OBJ_MIGHTBEDIRTY) != 0) { 941 int vfslocked; 942 vp = object->handle; 943 VM_OBJECT_UNLOCK(object); 944 (void) vn_start_write(vp, &mp, V_WAIT); 945 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 946 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 947 flags = (syncio || invalidate) ? OBJPC_SYNC : 0; 948 flags |= invalidate ? OBJPC_INVAL : 0; 949 VM_OBJECT_LOCK(object); 950 vm_object_page_clean(object, offset, offset + size, flags); 951 VM_OBJECT_UNLOCK(object); 952 VOP_UNLOCK(vp, 0); 953 VFS_UNLOCK_GIANT(vfslocked); 954 vn_finished_write(mp); 955 VM_OBJECT_LOCK(object); 956 } 957 if ((object->type == OBJT_VNODE || 958 object->type == OBJT_DEVICE) && invalidate) { 959 boolean_t purge; 960 purge = old_msync || (object->type == OBJT_DEVICE); 961 vm_object_page_remove(object, 962 OFF_TO_IDX(offset), 963 OFF_TO_IDX(offset + size + PAGE_MASK), 964 purge ? FALSE : TRUE); 965 } 966 VM_OBJECT_UNLOCK(object); 967 } 968 969 /* 970 * vm_object_madvise: 971 * 972 * Implements the madvise function at the object/page level. 973 * 974 * MADV_WILLNEED (any object) 975 * 976 * Activate the specified pages if they are resident. 977 * 978 * MADV_DONTNEED (any object) 979 * 980 * Deactivate the specified pages if they are resident. 981 * 982 * MADV_FREE (OBJT_DEFAULT/OBJT_SWAP objects, 983 * OBJ_ONEMAPPING only) 984 * 985 * Deactivate and clean the specified pages if they are 986 * resident. This permits the process to reuse the pages 987 * without faulting or the kernel to reclaim the pages 988 * without I/O. 989 */ 990 void 991 vm_object_madvise(vm_object_t object, vm_pindex_t pindex, int count, int advise) 992 { 993 vm_pindex_t end, tpindex; 994 vm_object_t backing_object, tobject; 995 vm_page_t m; 996 997 if (object == NULL) 998 return; 999 VM_OBJECT_LOCK(object); 1000 end = pindex + count; 1001 /* 1002 * Locate and adjust resident pages 1003 */ 1004 for (; pindex < end; pindex += 1) { 1005 relookup: 1006 tobject = object; 1007 tpindex = pindex; 1008 shadowlookup: 1009 /* 1010 * MADV_FREE only operates on OBJT_DEFAULT or OBJT_SWAP pages 1011 * and those pages must be OBJ_ONEMAPPING. 1012 */ 1013 if (advise == MADV_FREE) { 1014 if ((tobject->type != OBJT_DEFAULT && 1015 tobject->type != OBJT_SWAP) || 1016 (tobject->flags & OBJ_ONEMAPPING) == 0) { 1017 goto unlock_tobject; 1018 } 1019 } else if (tobject->type == OBJT_PHYS) 1020 goto unlock_tobject; 1021 m = vm_page_lookup(tobject, tpindex); 1022 if (m == NULL && advise == MADV_WILLNEED) { 1023 /* 1024 * If the page is cached, reactivate it. 1025 */ 1026 m = vm_page_alloc(tobject, tpindex, VM_ALLOC_IFCACHED | 1027 VM_ALLOC_NOBUSY); 1028 } 1029 if (m == NULL) { 1030 /* 1031 * There may be swap even if there is no backing page 1032 */ 1033 if (advise == MADV_FREE && tobject->type == OBJT_SWAP) 1034 swap_pager_freespace(tobject, tpindex, 1); 1035 /* 1036 * next object 1037 */ 1038 backing_object = tobject->backing_object; 1039 if (backing_object == NULL) 1040 goto unlock_tobject; 1041 VM_OBJECT_LOCK(backing_object); 1042 tpindex += OFF_TO_IDX(tobject->backing_object_offset); 1043 if (tobject != object) 1044 VM_OBJECT_UNLOCK(tobject); 1045 tobject = backing_object; 1046 goto shadowlookup; 1047 } else if (m->valid != VM_PAGE_BITS_ALL) 1048 goto unlock_tobject; 1049 /* 1050 * If the page is not in a normal state, skip it. 1051 */ 1052 vm_page_lock(m); 1053 if (m->hold_count != 0 || m->wire_count != 0) { 1054 vm_page_unlock(m); 1055 goto unlock_tobject; 1056 } 1057 KASSERT((m->flags & (PG_FICTITIOUS | PG_UNMANAGED)) == 0, 1058 ("vm_object_madvise: page %p is not managed", m)); 1059 if ((m->oflags & VPO_BUSY) || m->busy) { 1060 if (advise == MADV_WILLNEED) { 1061 /* 1062 * Reference the page before unlocking and 1063 * sleeping so that the page daemon is less 1064 * likely to reclaim it. 1065 */ 1066 vm_page_lock_queues(); 1067 vm_page_flag_set(m, PG_REFERENCED); 1068 vm_page_unlock_queues(); 1069 } 1070 vm_page_unlock(m); 1071 if (object != tobject) 1072 VM_OBJECT_UNLOCK(object); 1073 m->oflags |= VPO_WANTED; 1074 msleep(m, VM_OBJECT_MTX(tobject), PDROP | PVM, "madvpo", 1075 0); 1076 VM_OBJECT_LOCK(object); 1077 goto relookup; 1078 } 1079 if (advise == MADV_WILLNEED) { 1080 vm_page_activate(m); 1081 } else if (advise == MADV_DONTNEED) { 1082 vm_page_dontneed(m); 1083 } else if (advise == MADV_FREE) { 1084 /* 1085 * Mark the page clean. This will allow the page 1086 * to be freed up by the system. However, such pages 1087 * are often reused quickly by malloc()/free() 1088 * so we do not do anything that would cause 1089 * a page fault if we can help it. 1090 * 1091 * Specifically, we do not try to actually free 1092 * the page now nor do we try to put it in the 1093 * cache (which would cause a page fault on reuse). 1094 * 1095 * But we do make the page is freeable as we 1096 * can without actually taking the step of unmapping 1097 * it. 1098 */ 1099 pmap_clear_modify(m); 1100 m->dirty = 0; 1101 m->act_count = 0; 1102 vm_page_dontneed(m); 1103 } 1104 vm_page_unlock(m); 1105 if (advise == MADV_FREE && tobject->type == OBJT_SWAP) 1106 swap_pager_freespace(tobject, tpindex, 1); 1107 unlock_tobject: 1108 if (tobject != object) 1109 VM_OBJECT_UNLOCK(tobject); 1110 } 1111 VM_OBJECT_UNLOCK(object); 1112 } 1113 1114 /* 1115 * vm_object_shadow: 1116 * 1117 * Create a new object which is backed by the 1118 * specified existing object range. The source 1119 * object reference is deallocated. 1120 * 1121 * The new object and offset into that object 1122 * are returned in the source parameters. 1123 */ 1124 void 1125 vm_object_shadow( 1126 vm_object_t *object, /* IN/OUT */ 1127 vm_ooffset_t *offset, /* IN/OUT */ 1128 vm_size_t length) 1129 { 1130 vm_object_t source; 1131 vm_object_t result; 1132 1133 source = *object; 1134 1135 /* 1136 * Don't create the new object if the old object isn't shared. 1137 */ 1138 if (source != NULL) { 1139 VM_OBJECT_LOCK(source); 1140 if (source->ref_count == 1 && 1141 source->handle == NULL && 1142 (source->type == OBJT_DEFAULT || 1143 source->type == OBJT_SWAP)) { 1144 VM_OBJECT_UNLOCK(source); 1145 return; 1146 } 1147 VM_OBJECT_UNLOCK(source); 1148 } 1149 1150 /* 1151 * Allocate a new object with the given length. 1152 */ 1153 result = vm_object_allocate(OBJT_DEFAULT, atop(length)); 1154 1155 /* 1156 * The new object shadows the source object, adding a reference to it. 1157 * Our caller changes his reference to point to the new object, 1158 * removing a reference to the source object. Net result: no change 1159 * of reference count. 1160 * 1161 * Try to optimize the result object's page color when shadowing 1162 * in order to maintain page coloring consistency in the combined 1163 * shadowed object. 1164 */ 1165 result->backing_object = source; 1166 /* 1167 * Store the offset into the source object, and fix up the offset into 1168 * the new object. 1169 */ 1170 result->backing_object_offset = *offset; 1171 if (source != NULL) { 1172 VM_OBJECT_LOCK(source); 1173 LIST_INSERT_HEAD(&source->shadow_head, result, shadow_list); 1174 source->shadow_count++; 1175 #if VM_NRESERVLEVEL > 0 1176 result->flags |= source->flags & OBJ_COLORED; 1177 result->pg_color = (source->pg_color + OFF_TO_IDX(*offset)) & 1178 ((1 << (VM_NFREEORDER - 1)) - 1); 1179 #endif 1180 VM_OBJECT_UNLOCK(source); 1181 } 1182 1183 1184 /* 1185 * Return the new things 1186 */ 1187 *offset = 0; 1188 *object = result; 1189 } 1190 1191 /* 1192 * vm_object_split: 1193 * 1194 * Split the pages in a map entry into a new object. This affords 1195 * easier removal of unused pages, and keeps object inheritance from 1196 * being a negative impact on memory usage. 1197 */ 1198 void 1199 vm_object_split(vm_map_entry_t entry) 1200 { 1201 vm_page_t m, m_next; 1202 vm_object_t orig_object, new_object, source; 1203 vm_pindex_t idx, offidxstart; 1204 vm_size_t size; 1205 1206 orig_object = entry->object.vm_object; 1207 if (orig_object->type != OBJT_DEFAULT && orig_object->type != OBJT_SWAP) 1208 return; 1209 if (orig_object->ref_count <= 1) 1210 return; 1211 VM_OBJECT_UNLOCK(orig_object); 1212 1213 offidxstart = OFF_TO_IDX(entry->offset); 1214 size = atop(entry->end - entry->start); 1215 1216 /* 1217 * If swap_pager_copy() is later called, it will convert new_object 1218 * into a swap object. 1219 */ 1220 new_object = vm_object_allocate(OBJT_DEFAULT, size); 1221 1222 /* 1223 * At this point, the new object is still private, so the order in 1224 * which the original and new objects are locked does not matter. 1225 */ 1226 VM_OBJECT_LOCK(new_object); 1227 VM_OBJECT_LOCK(orig_object); 1228 source = orig_object->backing_object; 1229 if (source != NULL) { 1230 VM_OBJECT_LOCK(source); 1231 if ((source->flags & OBJ_DEAD) != 0) { 1232 VM_OBJECT_UNLOCK(source); 1233 VM_OBJECT_UNLOCK(orig_object); 1234 VM_OBJECT_UNLOCK(new_object); 1235 vm_object_deallocate(new_object); 1236 VM_OBJECT_LOCK(orig_object); 1237 return; 1238 } 1239 LIST_INSERT_HEAD(&source->shadow_head, 1240 new_object, shadow_list); 1241 source->shadow_count++; 1242 vm_object_reference_locked(source); /* for new_object */ 1243 vm_object_clear_flag(source, OBJ_ONEMAPPING); 1244 VM_OBJECT_UNLOCK(source); 1245 new_object->backing_object_offset = 1246 orig_object->backing_object_offset + entry->offset; 1247 new_object->backing_object = source; 1248 } 1249 if (orig_object->cred != NULL) { 1250 new_object->cred = orig_object->cred; 1251 crhold(orig_object->cred); 1252 new_object->charge = ptoa(size); 1253 KASSERT(orig_object->charge >= ptoa(size), 1254 ("orig_object->charge < 0")); 1255 orig_object->charge -= ptoa(size); 1256 } 1257 retry: 1258 m = vm_page_find_least(orig_object, offidxstart); 1259 for (; m != NULL && (idx = m->pindex - offidxstart) < size; 1260 m = m_next) { 1261 m_next = TAILQ_NEXT(m, listq); 1262 1263 /* 1264 * We must wait for pending I/O to complete before we can 1265 * rename the page. 1266 * 1267 * We do not have to VM_PROT_NONE the page as mappings should 1268 * not be changed by this operation. 1269 */ 1270 if ((m->oflags & VPO_BUSY) || m->busy) { 1271 VM_OBJECT_UNLOCK(new_object); 1272 m->oflags |= VPO_WANTED; 1273 msleep(m, VM_OBJECT_MTX(orig_object), PVM, "spltwt", 0); 1274 VM_OBJECT_LOCK(new_object); 1275 goto retry; 1276 } 1277 vm_page_lock(m); 1278 vm_page_rename(m, new_object, idx); 1279 vm_page_unlock(m); 1280 /* page automatically made dirty by rename and cache handled */ 1281 vm_page_busy(m); 1282 } 1283 if (orig_object->type == OBJT_SWAP) { 1284 /* 1285 * swap_pager_copy() can sleep, in which case the orig_object's 1286 * and new_object's locks are released and reacquired. 1287 */ 1288 swap_pager_copy(orig_object, new_object, offidxstart, 0); 1289 1290 /* 1291 * Transfer any cached pages from orig_object to new_object. 1292 */ 1293 if (__predict_false(orig_object->cache != NULL)) 1294 vm_page_cache_transfer(orig_object, offidxstart, 1295 new_object); 1296 } 1297 VM_OBJECT_UNLOCK(orig_object); 1298 TAILQ_FOREACH(m, &new_object->memq, listq) 1299 vm_page_wakeup(m); 1300 VM_OBJECT_UNLOCK(new_object); 1301 entry->object.vm_object = new_object; 1302 entry->offset = 0LL; 1303 vm_object_deallocate(orig_object); 1304 VM_OBJECT_LOCK(new_object); 1305 } 1306 1307 #define OBSC_TEST_ALL_SHADOWED 0x0001 1308 #define OBSC_COLLAPSE_NOWAIT 0x0002 1309 #define OBSC_COLLAPSE_WAIT 0x0004 1310 1311 static int 1312 vm_object_backing_scan(vm_object_t object, int op) 1313 { 1314 int r = 1; 1315 vm_page_t p; 1316 vm_object_t backing_object; 1317 vm_pindex_t backing_offset_index; 1318 1319 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1320 VM_OBJECT_LOCK_ASSERT(object->backing_object, MA_OWNED); 1321 1322 backing_object = object->backing_object; 1323 backing_offset_index = OFF_TO_IDX(object->backing_object_offset); 1324 1325 /* 1326 * Initial conditions 1327 */ 1328 if (op & OBSC_TEST_ALL_SHADOWED) { 1329 /* 1330 * We do not want to have to test for the existence of cache 1331 * or swap pages in the backing object. XXX but with the 1332 * new swapper this would be pretty easy to do. 1333 * 1334 * XXX what about anonymous MAP_SHARED memory that hasn't 1335 * been ZFOD faulted yet? If we do not test for this, the 1336 * shadow test may succeed! XXX 1337 */ 1338 if (backing_object->type != OBJT_DEFAULT) { 1339 return (0); 1340 } 1341 } 1342 if (op & OBSC_COLLAPSE_WAIT) { 1343 vm_object_set_flag(backing_object, OBJ_DEAD); 1344 } 1345 1346 /* 1347 * Our scan 1348 */ 1349 p = TAILQ_FIRST(&backing_object->memq); 1350 while (p) { 1351 vm_page_t next = TAILQ_NEXT(p, listq); 1352 vm_pindex_t new_pindex = p->pindex - backing_offset_index; 1353 1354 if (op & OBSC_TEST_ALL_SHADOWED) { 1355 vm_page_t pp; 1356 1357 /* 1358 * Ignore pages outside the parent object's range 1359 * and outside the parent object's mapping of the 1360 * backing object. 1361 * 1362 * note that we do not busy the backing object's 1363 * page. 1364 */ 1365 if ( 1366 p->pindex < backing_offset_index || 1367 new_pindex >= object->size 1368 ) { 1369 p = next; 1370 continue; 1371 } 1372 1373 /* 1374 * See if the parent has the page or if the parent's 1375 * object pager has the page. If the parent has the 1376 * page but the page is not valid, the parent's 1377 * object pager must have the page. 1378 * 1379 * If this fails, the parent does not completely shadow 1380 * the object and we might as well give up now. 1381 */ 1382 1383 pp = vm_page_lookup(object, new_pindex); 1384 if ( 1385 (pp == NULL || pp->valid == 0) && 1386 !vm_pager_has_page(object, new_pindex, NULL, NULL) 1387 ) { 1388 r = 0; 1389 break; 1390 } 1391 } 1392 1393 /* 1394 * Check for busy page 1395 */ 1396 if (op & (OBSC_COLLAPSE_WAIT | OBSC_COLLAPSE_NOWAIT)) { 1397 vm_page_t pp; 1398 1399 if (op & OBSC_COLLAPSE_NOWAIT) { 1400 if ((p->oflags & VPO_BUSY) || 1401 !p->valid || 1402 p->busy) { 1403 p = next; 1404 continue; 1405 } 1406 } else if (op & OBSC_COLLAPSE_WAIT) { 1407 if ((p->oflags & VPO_BUSY) || p->busy) { 1408 VM_OBJECT_UNLOCK(object); 1409 p->oflags |= VPO_WANTED; 1410 msleep(p, VM_OBJECT_MTX(backing_object), 1411 PDROP | PVM, "vmocol", 0); 1412 VM_OBJECT_LOCK(object); 1413 VM_OBJECT_LOCK(backing_object); 1414 /* 1415 * If we slept, anything could have 1416 * happened. Since the object is 1417 * marked dead, the backing offset 1418 * should not have changed so we 1419 * just restart our scan. 1420 */ 1421 p = TAILQ_FIRST(&backing_object->memq); 1422 continue; 1423 } 1424 } 1425 1426 KASSERT( 1427 p->object == backing_object, 1428 ("vm_object_backing_scan: object mismatch") 1429 ); 1430 1431 /* 1432 * Destroy any associated swap 1433 */ 1434 if (backing_object->type == OBJT_SWAP) { 1435 swap_pager_freespace( 1436 backing_object, 1437 p->pindex, 1438 1 1439 ); 1440 } 1441 1442 if ( 1443 p->pindex < backing_offset_index || 1444 new_pindex >= object->size 1445 ) { 1446 /* 1447 * Page is out of the parent object's range, we 1448 * can simply destroy it. 1449 */ 1450 vm_page_lock(p); 1451 KASSERT(!pmap_page_is_mapped(p), 1452 ("freeing mapped page %p", p)); 1453 if (p->wire_count == 0) 1454 vm_page_free(p); 1455 else 1456 vm_page_remove(p); 1457 vm_page_unlock(p); 1458 p = next; 1459 continue; 1460 } 1461 1462 pp = vm_page_lookup(object, new_pindex); 1463 if ( 1464 pp != NULL || 1465 vm_pager_has_page(object, new_pindex, NULL, NULL) 1466 ) { 1467 /* 1468 * page already exists in parent OR swap exists 1469 * for this location in the parent. Destroy 1470 * the original page from the backing object. 1471 * 1472 * Leave the parent's page alone 1473 */ 1474 vm_page_lock(p); 1475 KASSERT(!pmap_page_is_mapped(p), 1476 ("freeing mapped page %p", p)); 1477 if (p->wire_count == 0) 1478 vm_page_free(p); 1479 else 1480 vm_page_remove(p); 1481 vm_page_unlock(p); 1482 p = next; 1483 continue; 1484 } 1485 1486 #if VM_NRESERVLEVEL > 0 1487 /* 1488 * Rename the reservation. 1489 */ 1490 vm_reserv_rename(p, object, backing_object, 1491 backing_offset_index); 1492 #endif 1493 1494 /* 1495 * Page does not exist in parent, rename the 1496 * page from the backing object to the main object. 1497 * 1498 * If the page was mapped to a process, it can remain 1499 * mapped through the rename. 1500 */ 1501 vm_page_lock(p); 1502 vm_page_rename(p, object, new_pindex); 1503 vm_page_unlock(p); 1504 /* page automatically made dirty by rename */ 1505 } 1506 p = next; 1507 } 1508 return (r); 1509 } 1510 1511 1512 /* 1513 * this version of collapse allows the operation to occur earlier and 1514 * when paging_in_progress is true for an object... This is not a complete 1515 * operation, but should plug 99.9% of the rest of the leaks. 1516 */ 1517 static void 1518 vm_object_qcollapse(vm_object_t object) 1519 { 1520 vm_object_t backing_object = object->backing_object; 1521 1522 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1523 VM_OBJECT_LOCK_ASSERT(backing_object, MA_OWNED); 1524 1525 if (backing_object->ref_count != 1) 1526 return; 1527 1528 vm_object_backing_scan(object, OBSC_COLLAPSE_NOWAIT); 1529 } 1530 1531 /* 1532 * vm_object_collapse: 1533 * 1534 * Collapse an object with the object backing it. 1535 * Pages in the backing object are moved into the 1536 * parent, and the backing object is deallocated. 1537 */ 1538 void 1539 vm_object_collapse(vm_object_t object) 1540 { 1541 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1542 1543 while (TRUE) { 1544 vm_object_t backing_object; 1545 1546 /* 1547 * Verify that the conditions are right for collapse: 1548 * 1549 * The object exists and the backing object exists. 1550 */ 1551 if ((backing_object = object->backing_object) == NULL) 1552 break; 1553 1554 /* 1555 * we check the backing object first, because it is most likely 1556 * not collapsable. 1557 */ 1558 VM_OBJECT_LOCK(backing_object); 1559 if (backing_object->handle != NULL || 1560 (backing_object->type != OBJT_DEFAULT && 1561 backing_object->type != OBJT_SWAP) || 1562 (backing_object->flags & OBJ_DEAD) || 1563 object->handle != NULL || 1564 (object->type != OBJT_DEFAULT && 1565 object->type != OBJT_SWAP) || 1566 (object->flags & OBJ_DEAD)) { 1567 VM_OBJECT_UNLOCK(backing_object); 1568 break; 1569 } 1570 1571 if ( 1572 object->paging_in_progress != 0 || 1573 backing_object->paging_in_progress != 0 1574 ) { 1575 vm_object_qcollapse(object); 1576 VM_OBJECT_UNLOCK(backing_object); 1577 break; 1578 } 1579 /* 1580 * We know that we can either collapse the backing object (if 1581 * the parent is the only reference to it) or (perhaps) have 1582 * the parent bypass the object if the parent happens to shadow 1583 * all the resident pages in the entire backing object. 1584 * 1585 * This is ignoring pager-backed pages such as swap pages. 1586 * vm_object_backing_scan fails the shadowing test in this 1587 * case. 1588 */ 1589 if (backing_object->ref_count == 1) { 1590 /* 1591 * If there is exactly one reference to the backing 1592 * object, we can collapse it into the parent. 1593 */ 1594 vm_object_backing_scan(object, OBSC_COLLAPSE_WAIT); 1595 1596 #if VM_NRESERVLEVEL > 0 1597 /* 1598 * Break any reservations from backing_object. 1599 */ 1600 if (__predict_false(!LIST_EMPTY(&backing_object->rvq))) 1601 vm_reserv_break_all(backing_object); 1602 #endif 1603 1604 /* 1605 * Move the pager from backing_object to object. 1606 */ 1607 if (backing_object->type == OBJT_SWAP) { 1608 /* 1609 * swap_pager_copy() can sleep, in which case 1610 * the backing_object's and object's locks are 1611 * released and reacquired. 1612 */ 1613 swap_pager_copy( 1614 backing_object, 1615 object, 1616 OFF_TO_IDX(object->backing_object_offset), TRUE); 1617 1618 /* 1619 * Free any cached pages from backing_object. 1620 */ 1621 if (__predict_false(backing_object->cache != NULL)) 1622 vm_page_cache_free(backing_object, 0, 0); 1623 } 1624 /* 1625 * Object now shadows whatever backing_object did. 1626 * Note that the reference to 1627 * backing_object->backing_object moves from within 1628 * backing_object to within object. 1629 */ 1630 LIST_REMOVE(object, shadow_list); 1631 backing_object->shadow_count--; 1632 if (backing_object->backing_object) { 1633 VM_OBJECT_LOCK(backing_object->backing_object); 1634 LIST_REMOVE(backing_object, shadow_list); 1635 LIST_INSERT_HEAD( 1636 &backing_object->backing_object->shadow_head, 1637 object, shadow_list); 1638 /* 1639 * The shadow_count has not changed. 1640 */ 1641 VM_OBJECT_UNLOCK(backing_object->backing_object); 1642 } 1643 object->backing_object = backing_object->backing_object; 1644 object->backing_object_offset += 1645 backing_object->backing_object_offset; 1646 1647 /* 1648 * Discard backing_object. 1649 * 1650 * Since the backing object has no pages, no pager left, 1651 * and no object references within it, all that is 1652 * necessary is to dispose of it. 1653 */ 1654 KASSERT(backing_object->ref_count == 1, ( 1655 "backing_object %p was somehow re-referenced during collapse!", 1656 backing_object)); 1657 VM_OBJECT_UNLOCK(backing_object); 1658 vm_object_destroy(backing_object); 1659 1660 object_collapses++; 1661 } else { 1662 vm_object_t new_backing_object; 1663 1664 /* 1665 * If we do not entirely shadow the backing object, 1666 * there is nothing we can do so we give up. 1667 */ 1668 if (object->resident_page_count != object->size && 1669 vm_object_backing_scan(object, 1670 OBSC_TEST_ALL_SHADOWED) == 0) { 1671 VM_OBJECT_UNLOCK(backing_object); 1672 break; 1673 } 1674 1675 /* 1676 * Make the parent shadow the next object in the 1677 * chain. Deallocating backing_object will not remove 1678 * it, since its reference count is at least 2. 1679 */ 1680 LIST_REMOVE(object, shadow_list); 1681 backing_object->shadow_count--; 1682 1683 new_backing_object = backing_object->backing_object; 1684 if ((object->backing_object = new_backing_object) != NULL) { 1685 VM_OBJECT_LOCK(new_backing_object); 1686 LIST_INSERT_HEAD( 1687 &new_backing_object->shadow_head, 1688 object, 1689 shadow_list 1690 ); 1691 new_backing_object->shadow_count++; 1692 vm_object_reference_locked(new_backing_object); 1693 VM_OBJECT_UNLOCK(new_backing_object); 1694 object->backing_object_offset += 1695 backing_object->backing_object_offset; 1696 } 1697 1698 /* 1699 * Drop the reference count on backing_object. Since 1700 * its ref_count was at least 2, it will not vanish. 1701 */ 1702 backing_object->ref_count--; 1703 VM_OBJECT_UNLOCK(backing_object); 1704 object_bypasses++; 1705 } 1706 1707 /* 1708 * Try again with this object's new backing object. 1709 */ 1710 } 1711 } 1712 1713 /* 1714 * vm_object_page_remove: 1715 * 1716 * For the given object, either frees or invalidates each of the 1717 * specified pages. In general, a page is freed. However, if a 1718 * page is wired for any reason other than the existence of a 1719 * managed, wired mapping, then it may be invalidated but not 1720 * removed from the object. Pages are specified by the given 1721 * range ["start", "end") and Boolean "clean_only". As a 1722 * special case, if "end" is zero, then the range extends from 1723 * "start" to the end of the object. If "clean_only" is TRUE, 1724 * then only the non-dirty pages within the specified range are 1725 * affected. 1726 * 1727 * In general, this operation should only be performed on objects 1728 * that contain managed pages. There are two exceptions. First, 1729 * it may be performed on the kernel and kmem objects. Second, 1730 * it may be used by msync(..., MS_INVALIDATE) to invalidate 1731 * device-backed pages. In both of these cases, "clean_only" 1732 * must be FALSE. 1733 * 1734 * The object must be locked. 1735 */ 1736 void 1737 vm_object_page_remove(vm_object_t object, vm_pindex_t start, vm_pindex_t end, 1738 boolean_t clean_only) 1739 { 1740 vm_page_t p, next; 1741 int wirings; 1742 1743 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1744 if (object->resident_page_count == 0) 1745 goto skipmemq; 1746 1747 /* 1748 * Since physically-backed objects do not use managed pages, we can't 1749 * remove pages from the object (we must instead remove the page 1750 * references, and then destroy the object). 1751 */ 1752 KASSERT(object->type != OBJT_PHYS || object == kernel_object || 1753 object == kmem_object, 1754 ("attempt to remove pages from a physical object")); 1755 1756 vm_object_pip_add(object, 1); 1757 again: 1758 p = vm_page_find_least(object, start); 1759 1760 /* 1761 * Assert: the variable p is either (1) the page with the 1762 * least pindex greater than or equal to the parameter pindex 1763 * or (2) NULL. 1764 */ 1765 for (; 1766 p != NULL && (p->pindex < end || end == 0); 1767 p = next) { 1768 next = TAILQ_NEXT(p, listq); 1769 1770 /* 1771 * If the page is wired for any reason besides the 1772 * existence of managed, wired mappings, then it cannot 1773 * be freed. For example, fictitious pages, which 1774 * represent device memory, are inherently wired and 1775 * cannot be freed. They can, however, be invalidated 1776 * if "clean_only" is FALSE. 1777 */ 1778 vm_page_lock(p); 1779 if ((wirings = p->wire_count) != 0 && 1780 (wirings = pmap_page_wired_mappings(p)) != p->wire_count) { 1781 /* Fictitious pages do not have managed mappings. */ 1782 if ((p->flags & PG_FICTITIOUS) == 0) 1783 pmap_remove_all(p); 1784 /* Account for removal of managed, wired mappings. */ 1785 p->wire_count -= wirings; 1786 if (!clean_only) { 1787 p->valid = 0; 1788 vm_page_undirty(p); 1789 } 1790 vm_page_unlock(p); 1791 continue; 1792 } 1793 if (vm_page_sleep_if_busy(p, TRUE, "vmopar")) 1794 goto again; 1795 KASSERT((p->flags & PG_FICTITIOUS) == 0, 1796 ("vm_object_page_remove: page %p is fictitious", p)); 1797 if (clean_only && p->valid) { 1798 pmap_remove_write(p); 1799 if (p->dirty) { 1800 vm_page_unlock(p); 1801 continue; 1802 } 1803 } 1804 pmap_remove_all(p); 1805 /* Account for removal of managed, wired mappings. */ 1806 if (wirings != 0) 1807 p->wire_count -= wirings; 1808 vm_page_free(p); 1809 vm_page_unlock(p); 1810 } 1811 vm_object_pip_wakeup(object); 1812 skipmemq: 1813 if (__predict_false(object->cache != NULL)) 1814 vm_page_cache_free(object, start, end); 1815 } 1816 1817 /* 1818 * Populate the specified range of the object with valid pages. Returns 1819 * TRUE if the range is successfully populated and FALSE otherwise. 1820 * 1821 * Note: This function should be optimized to pass a larger array of 1822 * pages to vm_pager_get_pages() before it is applied to a non- 1823 * OBJT_DEVICE object. 1824 * 1825 * The object must be locked. 1826 */ 1827 boolean_t 1828 vm_object_populate(vm_object_t object, vm_pindex_t start, vm_pindex_t end) 1829 { 1830 vm_page_t m, ma[1]; 1831 vm_pindex_t pindex; 1832 int rv; 1833 1834 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1835 for (pindex = start; pindex < end; pindex++) { 1836 m = vm_page_grab(object, pindex, VM_ALLOC_NORMAL | 1837 VM_ALLOC_RETRY); 1838 if (m->valid != VM_PAGE_BITS_ALL) { 1839 ma[0] = m; 1840 rv = vm_pager_get_pages(object, ma, 1, 0); 1841 m = vm_page_lookup(object, pindex); 1842 if (m == NULL) 1843 break; 1844 if (rv != VM_PAGER_OK) { 1845 vm_page_lock(m); 1846 vm_page_free(m); 1847 vm_page_unlock(m); 1848 break; 1849 } 1850 } 1851 /* 1852 * Keep "m" busy because a subsequent iteration may unlock 1853 * the object. 1854 */ 1855 } 1856 if (pindex > start) { 1857 m = vm_page_lookup(object, start); 1858 while (m != NULL && m->pindex < pindex) { 1859 vm_page_wakeup(m); 1860 m = TAILQ_NEXT(m, listq); 1861 } 1862 } 1863 return (pindex == end); 1864 } 1865 1866 /* 1867 * Routine: vm_object_coalesce 1868 * Function: Coalesces two objects backing up adjoining 1869 * regions of memory into a single object. 1870 * 1871 * returns TRUE if objects were combined. 1872 * 1873 * NOTE: Only works at the moment if the second object is NULL - 1874 * if it's not, which object do we lock first? 1875 * 1876 * Parameters: 1877 * prev_object First object to coalesce 1878 * prev_offset Offset into prev_object 1879 * prev_size Size of reference to prev_object 1880 * next_size Size of reference to the second object 1881 * reserved Indicator that extension region has 1882 * swap accounted for 1883 * 1884 * Conditions: 1885 * The object must *not* be locked. 1886 */ 1887 boolean_t 1888 vm_object_coalesce(vm_object_t prev_object, vm_ooffset_t prev_offset, 1889 vm_size_t prev_size, vm_size_t next_size, boolean_t reserved) 1890 { 1891 vm_pindex_t next_pindex; 1892 1893 if (prev_object == NULL) 1894 return (TRUE); 1895 VM_OBJECT_LOCK(prev_object); 1896 if (prev_object->type != OBJT_DEFAULT && 1897 prev_object->type != OBJT_SWAP) { 1898 VM_OBJECT_UNLOCK(prev_object); 1899 return (FALSE); 1900 } 1901 1902 /* 1903 * Try to collapse the object first 1904 */ 1905 vm_object_collapse(prev_object); 1906 1907 /* 1908 * Can't coalesce if: . more than one reference . paged out . shadows 1909 * another object . has a copy elsewhere (any of which mean that the 1910 * pages not mapped to prev_entry may be in use anyway) 1911 */ 1912 if (prev_object->backing_object != NULL) { 1913 VM_OBJECT_UNLOCK(prev_object); 1914 return (FALSE); 1915 } 1916 1917 prev_size >>= PAGE_SHIFT; 1918 next_size >>= PAGE_SHIFT; 1919 next_pindex = OFF_TO_IDX(prev_offset) + prev_size; 1920 1921 if ((prev_object->ref_count > 1) && 1922 (prev_object->size != next_pindex)) { 1923 VM_OBJECT_UNLOCK(prev_object); 1924 return (FALSE); 1925 } 1926 1927 /* 1928 * Account for the charge. 1929 */ 1930 if (prev_object->cred != NULL) { 1931 1932 /* 1933 * If prev_object was charged, then this mapping, 1934 * althought not charged now, may become writable 1935 * later. Non-NULL cred in the object would prevent 1936 * swap reservation during enabling of the write 1937 * access, so reserve swap now. Failed reservation 1938 * cause allocation of the separate object for the map 1939 * entry, and swap reservation for this entry is 1940 * managed in appropriate time. 1941 */ 1942 if (!reserved && !swap_reserve_by_cred(ptoa(next_size), 1943 prev_object->cred)) { 1944 return (FALSE); 1945 } 1946 prev_object->charge += ptoa(next_size); 1947 } 1948 1949 /* 1950 * Remove any pages that may still be in the object from a previous 1951 * deallocation. 1952 */ 1953 if (next_pindex < prev_object->size) { 1954 vm_object_page_remove(prev_object, 1955 next_pindex, 1956 next_pindex + next_size, FALSE); 1957 if (prev_object->type == OBJT_SWAP) 1958 swap_pager_freespace(prev_object, 1959 next_pindex, next_size); 1960 #if 0 1961 if (prev_object->cred != NULL) { 1962 KASSERT(prev_object->charge >= 1963 ptoa(prev_object->size - next_pindex), 1964 ("object %p overcharged 1 %jx %jx", prev_object, 1965 (uintmax_t)next_pindex, (uintmax_t)next_size)); 1966 prev_object->charge -= ptoa(prev_object->size - 1967 next_pindex); 1968 } 1969 #endif 1970 } 1971 1972 /* 1973 * Extend the object if necessary. 1974 */ 1975 if (next_pindex + next_size > prev_object->size) 1976 prev_object->size = next_pindex + next_size; 1977 1978 VM_OBJECT_UNLOCK(prev_object); 1979 return (TRUE); 1980 } 1981 1982 void 1983 vm_object_set_writeable_dirty(vm_object_t object) 1984 { 1985 1986 VM_OBJECT_LOCK_ASSERT(object, MA_OWNED); 1987 if (object->type != OBJT_VNODE) 1988 return; 1989 object->generation++; 1990 if ((object->flags & OBJ_MIGHTBEDIRTY) != 0) 1991 return; 1992 vm_object_set_flag(object, OBJ_MIGHTBEDIRTY); 1993 } 1994 1995 #include "opt_ddb.h" 1996 #ifdef DDB 1997 #include <sys/kernel.h> 1998 1999 #include <sys/cons.h> 2000 2001 #include <ddb/ddb.h> 2002 2003 static int 2004 _vm_object_in_map(vm_map_t map, vm_object_t object, vm_map_entry_t entry) 2005 { 2006 vm_map_t tmpm; 2007 vm_map_entry_t tmpe; 2008 vm_object_t obj; 2009 int entcount; 2010 2011 if (map == 0) 2012 return 0; 2013 2014 if (entry == 0) { 2015 tmpe = map->header.next; 2016 entcount = map->nentries; 2017 while (entcount-- && (tmpe != &map->header)) { 2018 if (_vm_object_in_map(map, object, tmpe)) { 2019 return 1; 2020 } 2021 tmpe = tmpe->next; 2022 } 2023 } else if (entry->eflags & MAP_ENTRY_IS_SUB_MAP) { 2024 tmpm = entry->object.sub_map; 2025 tmpe = tmpm->header.next; 2026 entcount = tmpm->nentries; 2027 while (entcount-- && tmpe != &tmpm->header) { 2028 if (_vm_object_in_map(tmpm, object, tmpe)) { 2029 return 1; 2030 } 2031 tmpe = tmpe->next; 2032 } 2033 } else if ((obj = entry->object.vm_object) != NULL) { 2034 for (; obj; obj = obj->backing_object) 2035 if (obj == object) { 2036 return 1; 2037 } 2038 } 2039 return 0; 2040 } 2041 2042 static int 2043 vm_object_in_map(vm_object_t object) 2044 { 2045 struct proc *p; 2046 2047 /* sx_slock(&allproc_lock); */ 2048 FOREACH_PROC_IN_SYSTEM(p) { 2049 if (!p->p_vmspace /* || (p->p_flag & (P_SYSTEM|P_WEXIT)) */) 2050 continue; 2051 if (_vm_object_in_map(&p->p_vmspace->vm_map, object, 0)) { 2052 /* sx_sunlock(&allproc_lock); */ 2053 return 1; 2054 } 2055 } 2056 /* sx_sunlock(&allproc_lock); */ 2057 if (_vm_object_in_map(kernel_map, object, 0)) 2058 return 1; 2059 if (_vm_object_in_map(kmem_map, object, 0)) 2060 return 1; 2061 if (_vm_object_in_map(pager_map, object, 0)) 2062 return 1; 2063 if (_vm_object_in_map(buffer_map, object, 0)) 2064 return 1; 2065 return 0; 2066 } 2067 2068 DB_SHOW_COMMAND(vmochk, vm_object_check) 2069 { 2070 vm_object_t object; 2071 2072 /* 2073 * make sure that internal objs are in a map somewhere 2074 * and none have zero ref counts. 2075 */ 2076 TAILQ_FOREACH(object, &vm_object_list, object_list) { 2077 if (object->handle == NULL && 2078 (object->type == OBJT_DEFAULT || object->type == OBJT_SWAP)) { 2079 if (object->ref_count == 0) { 2080 db_printf("vmochk: internal obj has zero ref count: %ld\n", 2081 (long)object->size); 2082 } 2083 if (!vm_object_in_map(object)) { 2084 db_printf( 2085 "vmochk: internal obj is not in a map: " 2086 "ref: %d, size: %lu: 0x%lx, backing_object: %p\n", 2087 object->ref_count, (u_long)object->size, 2088 (u_long)object->size, 2089 (void *)object->backing_object); 2090 } 2091 } 2092 } 2093 } 2094 2095 /* 2096 * vm_object_print: [ debug ] 2097 */ 2098 DB_SHOW_COMMAND(object, vm_object_print_static) 2099 { 2100 /* XXX convert args. */ 2101 vm_object_t object = (vm_object_t)addr; 2102 boolean_t full = have_addr; 2103 2104 vm_page_t p; 2105 2106 /* XXX count is an (unused) arg. Avoid shadowing it. */ 2107 #define count was_count 2108 2109 int count; 2110 2111 if (object == NULL) 2112 return; 2113 2114 db_iprintf( 2115 "Object %p: type=%d, size=0x%jx, res=%d, ref=%d, flags=0x%x ruid %d charge %jx\n", 2116 object, (int)object->type, (uintmax_t)object->size, 2117 object->resident_page_count, object->ref_count, object->flags, 2118 object->cred ? object->cred->cr_ruid : -1, (uintmax_t)object->charge); 2119 db_iprintf(" sref=%d, backing_object(%d)=(%p)+0x%jx\n", 2120 object->shadow_count, 2121 object->backing_object ? object->backing_object->ref_count : 0, 2122 object->backing_object, (uintmax_t)object->backing_object_offset); 2123 2124 if (!full) 2125 return; 2126 2127 db_indent += 2; 2128 count = 0; 2129 TAILQ_FOREACH(p, &object->memq, listq) { 2130 if (count == 0) 2131 db_iprintf("memory:="); 2132 else if (count == 6) { 2133 db_printf("\n"); 2134 db_iprintf(" ..."); 2135 count = 0; 2136 } else 2137 db_printf(","); 2138 count++; 2139 2140 db_printf("(off=0x%jx,page=0x%jx)", 2141 (uintmax_t)p->pindex, (uintmax_t)VM_PAGE_TO_PHYS(p)); 2142 } 2143 if (count != 0) 2144 db_printf("\n"); 2145 db_indent -= 2; 2146 } 2147 2148 /* XXX. */ 2149 #undef count 2150 2151 /* XXX need this non-static entry for calling from vm_map_print. */ 2152 void 2153 vm_object_print( 2154 /* db_expr_t */ long addr, 2155 boolean_t have_addr, 2156 /* db_expr_t */ long count, 2157 char *modif) 2158 { 2159 vm_object_print_static(addr, have_addr, count, modif); 2160 } 2161 2162 DB_SHOW_COMMAND(vmopag, vm_object_print_pages) 2163 { 2164 vm_object_t object; 2165 vm_pindex_t fidx; 2166 vm_paddr_t pa; 2167 vm_page_t m, prev_m; 2168 int rcount, nl, c; 2169 2170 nl = 0; 2171 TAILQ_FOREACH(object, &vm_object_list, object_list) { 2172 db_printf("new object: %p\n", (void *)object); 2173 if (nl > 18) { 2174 c = cngetc(); 2175 if (c != ' ') 2176 return; 2177 nl = 0; 2178 } 2179 nl++; 2180 rcount = 0; 2181 fidx = 0; 2182 pa = -1; 2183 TAILQ_FOREACH(m, &object->memq, listq) { 2184 if (m->pindex > 128) 2185 break; 2186 if ((prev_m = TAILQ_PREV(m, pglist, listq)) != NULL && 2187 prev_m->pindex + 1 != m->pindex) { 2188 if (rcount) { 2189 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2190 (long)fidx, rcount, (long)pa); 2191 if (nl > 18) { 2192 c = cngetc(); 2193 if (c != ' ') 2194 return; 2195 nl = 0; 2196 } 2197 nl++; 2198 rcount = 0; 2199 } 2200 } 2201 if (rcount && 2202 (VM_PAGE_TO_PHYS(m) == pa + rcount * PAGE_SIZE)) { 2203 ++rcount; 2204 continue; 2205 } 2206 if (rcount) { 2207 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2208 (long)fidx, rcount, (long)pa); 2209 if (nl > 18) { 2210 c = cngetc(); 2211 if (c != ' ') 2212 return; 2213 nl = 0; 2214 } 2215 nl++; 2216 } 2217 fidx = m->pindex; 2218 pa = VM_PAGE_TO_PHYS(m); 2219 rcount = 1; 2220 } 2221 if (rcount) { 2222 db_printf(" index(%ld)run(%d)pa(0x%lx)\n", 2223 (long)fidx, rcount, (long)pa); 2224 if (nl > 18) { 2225 c = cngetc(); 2226 if (c != ' ') 2227 return; 2228 nl = 0; 2229 } 2230 nl++; 2231 } 2232 } 2233 } 2234 #endif /* DDB */ 2235