1 /* 2 * Copyright (c) 1991 Regents of the University of California. 3 * 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 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * from: @(#)vm_page.c 7.4 (Berkeley) 5/7/91 37 * $Id: vm_page.c,v 1.30 1995/04/16 11:50:45 davidg Exp $ 38 */ 39 40 /* 41 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 42 * All rights reserved. 43 * 44 * Authors: Avadis Tevanian, Jr., Michael Wayne Young 45 * 46 * Permission to use, copy, modify and distribute this software and 47 * its documentation is hereby granted, provided that both the copyright 48 * notice and this permission notice appear in all copies of the 49 * software, derivative works or modified versions, and any portions 50 * thereof, and that both notices appear in supporting documentation. 51 * 52 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 53 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 54 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 55 * 56 * Carnegie Mellon requests users of this software to return to 57 * 58 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 59 * School of Computer Science 60 * Carnegie Mellon University 61 * Pittsburgh PA 15213-3890 62 * 63 * any improvements or extensions that they make and grant Carnegie the 64 * rights to redistribute these changes. 65 */ 66 67 /* 68 * Resident memory management module. 69 */ 70 71 #include <sys/param.h> 72 #include <sys/systm.h> 73 #include <sys/proc.h> 74 75 #include <vm/vm.h> 76 #include <vm/vm_kern.h> 77 #include <vm/vm_page.h> 78 #include <vm/vm_map.h> 79 #include <vm/vm_pageout.h> 80 81 /* 82 * Associated with page of user-allocatable memory is a 83 * page structure. 84 */ 85 86 struct pglist *vm_page_buckets; /* Array of buckets */ 87 int vm_page_bucket_count; /* How big is array? */ 88 int vm_page_hash_mask; /* Mask for hash function */ 89 simple_lock_data_t bucket_lock; /* lock for all buckets XXX */ 90 91 struct pglist vm_page_queue_free; 92 struct pglist vm_page_queue_active; 93 struct pglist vm_page_queue_inactive; 94 struct pglist vm_page_queue_cache; 95 simple_lock_data_t vm_page_queue_lock; 96 simple_lock_data_t vm_page_queue_free_lock; 97 98 /* has physical page allocation been initialized? */ 99 boolean_t vm_page_startup_initialized; 100 101 vm_page_t vm_page_array; 102 int vm_page_array_size; 103 long first_page; 104 long last_page; 105 vm_offset_t first_phys_addr; 106 vm_offset_t last_phys_addr; 107 vm_size_t page_mask; 108 int page_shift; 109 110 /* 111 * map of contiguous valid DEV_BSIZE chunks in a page 112 * (this list is valid for page sizes upto 16*DEV_BSIZE) 113 */ 114 static u_short vm_page_dev_bsize_chunks[] = { 115 0x0, 0x1, 0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f, 0xff, 116 0x1ff, 0x3ff, 0x7ff, 0xfff, 0x1fff, 0x3fff, 0x7fff, 0xffff 117 }; 118 119 120 /* 121 * vm_set_page_size: 122 * 123 * Sets the page size, perhaps based upon the memory 124 * size. Must be called before any use of page-size 125 * dependent functions. 126 * 127 * Sets page_shift and page_mask from cnt.v_page_size. 128 */ 129 void 130 vm_set_page_size() 131 { 132 133 if (cnt.v_page_size == 0) 134 cnt.v_page_size = DEFAULT_PAGE_SIZE; 135 page_mask = cnt.v_page_size - 1; 136 if ((page_mask & cnt.v_page_size) != 0) 137 panic("vm_set_page_size: page size not a power of two"); 138 for (page_shift = 0;; page_shift++) 139 if ((1 << page_shift) == cnt.v_page_size) 140 break; 141 } 142 143 /* 144 * vm_page_startup: 145 * 146 * Initializes the resident memory module. 147 * 148 * Allocates memory for the page cells, and 149 * for the object/offset-to-page hash table headers. 150 * Each page cell is initialized and placed on the free list. 151 */ 152 153 vm_offset_t 154 vm_page_startup(starta, enda, vaddr) 155 register vm_offset_t starta; 156 vm_offset_t enda; 157 register vm_offset_t vaddr; 158 { 159 register vm_offset_t mapped; 160 register vm_page_t m; 161 register struct pglist *bucket; 162 vm_size_t npages, page_range; 163 register vm_offset_t new_start; 164 int i; 165 vm_offset_t pa; 166 int nblocks; 167 vm_offset_t first_managed_page; 168 169 /* the biggest memory array is the second group of pages */ 170 vm_offset_t start; 171 vm_offset_t biggestone, biggestsize; 172 173 vm_offset_t total; 174 175 total = 0; 176 biggestsize = 0; 177 biggestone = 0; 178 nblocks = 0; 179 vaddr = round_page(vaddr); 180 181 for (i = 0; phys_avail[i + 1]; i += 2) { 182 phys_avail[i] = round_page(phys_avail[i]); 183 phys_avail[i + 1] = trunc_page(phys_avail[i + 1]); 184 } 185 186 for (i = 0; phys_avail[i + 1]; i += 2) { 187 int size = phys_avail[i + 1] - phys_avail[i]; 188 189 if (size > biggestsize) { 190 biggestone = i; 191 biggestsize = size; 192 } 193 ++nblocks; 194 total += size; 195 } 196 197 start = phys_avail[biggestone]; 198 199 200 /* 201 * Initialize the locks 202 */ 203 204 simple_lock_init(&vm_page_queue_free_lock); 205 simple_lock_init(&vm_page_queue_lock); 206 207 /* 208 * Initialize the queue headers for the free queue, the active queue 209 * and the inactive queue. 210 */ 211 212 TAILQ_INIT(&vm_page_queue_free); 213 TAILQ_INIT(&vm_page_queue_active); 214 TAILQ_INIT(&vm_page_queue_inactive); 215 TAILQ_INIT(&vm_page_queue_cache); 216 217 /* 218 * Allocate (and initialize) the hash table buckets. 219 * 220 * The number of buckets MUST BE a power of 2, and the actual value is 221 * the next power of 2 greater than the number of physical pages in 222 * the system. 223 * 224 * Note: This computation can be tweaked if desired. 225 */ 226 vm_page_buckets = (struct pglist *) vaddr; 227 bucket = vm_page_buckets; 228 if (vm_page_bucket_count == 0) { 229 vm_page_bucket_count = 1; 230 while (vm_page_bucket_count < atop(total)) 231 vm_page_bucket_count <<= 1; 232 } 233 vm_page_hash_mask = vm_page_bucket_count - 1; 234 235 /* 236 * Validate these addresses. 237 */ 238 239 new_start = start + vm_page_bucket_count * sizeof(struct pglist); 240 new_start = round_page(new_start); 241 mapped = vaddr; 242 vaddr = pmap_map(mapped, start, new_start, 243 VM_PROT_READ | VM_PROT_WRITE); 244 start = new_start; 245 bzero((caddr_t) mapped, vaddr - mapped); 246 mapped = vaddr; 247 248 for (i = 0; i < vm_page_bucket_count; i++) { 249 TAILQ_INIT(bucket); 250 bucket++; 251 } 252 253 simple_lock_init(&bucket_lock); 254 255 /* 256 * round (or truncate) the addresses to our page size. 257 */ 258 259 /* 260 * Pre-allocate maps and map entries that cannot be dynamically 261 * allocated via malloc(). The maps include the kernel_map and 262 * kmem_map which must be initialized before malloc() will work 263 * (obviously). Also could include pager maps which would be 264 * allocated before kmeminit. 265 * 266 * Allow some kernel map entries... this should be plenty since people 267 * shouldn't be cluttering up the kernel map (they should use their 268 * own maps). 269 */ 270 271 kentry_data_size = MAX_KMAP * sizeof(struct vm_map) + 272 MAX_KMAPENT * sizeof(struct vm_map_entry); 273 kentry_data_size = round_page(kentry_data_size); 274 kentry_data = (vm_offset_t) vaddr; 275 vaddr += kentry_data_size; 276 277 /* 278 * Validate these zone addresses. 279 */ 280 281 new_start = start + (vaddr - mapped); 282 pmap_map(mapped, start, new_start, VM_PROT_READ | VM_PROT_WRITE); 283 bzero((caddr_t) mapped, (vaddr - mapped)); 284 start = round_page(new_start); 285 286 /* 287 * Compute the number of pages of memory that will be available for 288 * use (taking into account the overhead of a page structure per 289 * page). 290 */ 291 292 first_page = phys_avail[0] / PAGE_SIZE; 293 294 /* for VM_PAGE_CHECK() */ 295 last_page = phys_avail[(nblocks - 1) * 2 + 1] / PAGE_SIZE; 296 297 page_range = last_page - (phys_avail[0] / PAGE_SIZE); 298 npages = (total - (page_range * sizeof(struct vm_page)) - 299 (start - phys_avail[biggestone])) / PAGE_SIZE; 300 301 /* 302 * Initialize the mem entry structures now, and put them in the free 303 * queue. 304 */ 305 306 vm_page_array = (vm_page_t) vaddr; 307 mapped = vaddr; 308 309 310 /* 311 * Validate these addresses. 312 */ 313 314 new_start = round_page(start + page_range * sizeof(struct vm_page)); 315 mapped = pmap_map(mapped, start, new_start, 316 VM_PROT_READ | VM_PROT_WRITE); 317 start = new_start; 318 319 first_managed_page = start / PAGE_SIZE; 320 321 /* 322 * Clear all of the page structures 323 */ 324 bzero((caddr_t) vm_page_array, page_range * sizeof(struct vm_page)); 325 vm_page_array_size = page_range; 326 327 cnt.v_page_count = 0; 328 cnt.v_free_count = 0; 329 for (i = 0; phys_avail[i + 1] && npages > 0; i += 2) { 330 if (i == biggestone) 331 pa = ptoa(first_managed_page); 332 else 333 pa = phys_avail[i]; 334 while (pa < phys_avail[i + 1] && npages-- > 0) { 335 ++cnt.v_page_count; 336 ++cnt.v_free_count; 337 m = PHYS_TO_VM_PAGE(pa); 338 m->flags = PG_FREE; 339 m->phys_addr = pa; 340 TAILQ_INSERT_TAIL(&vm_page_queue_free, m, pageq); 341 pa += PAGE_SIZE; 342 } 343 } 344 345 /* 346 * Initialize vm_pages_needed lock here - don't wait for pageout 347 * daemon XXX 348 */ 349 simple_lock_init(&vm_pages_needed_lock); 350 351 return (mapped); 352 } 353 354 /* 355 * vm_page_hash: 356 * 357 * Distributes the object/offset key pair among hash buckets. 358 * 359 * NOTE: This macro depends on vm_page_bucket_count being a power of 2. 360 */ 361 inline const int 362 vm_page_hash(object, offset) 363 vm_object_t object; 364 vm_offset_t offset; 365 { 366 return ((unsigned) object + offset / NBPG) & vm_page_hash_mask; 367 } 368 369 /* 370 * vm_page_insert: [ internal use only ] 371 * 372 * Inserts the given mem entry into the object/object-page 373 * table and object list. 374 * 375 * The object and page must be locked, and must be splhigh. 376 */ 377 378 inline void 379 vm_page_insert(mem, object, offset) 380 register vm_page_t mem; 381 register vm_object_t object; 382 register vm_offset_t offset; 383 { 384 register struct pglist *bucket; 385 386 VM_PAGE_CHECK(mem); 387 388 if (mem->flags & PG_TABLED) 389 panic("vm_page_insert: already inserted"); 390 391 /* 392 * Record the object/offset pair in this page 393 */ 394 395 mem->object = object; 396 mem->offset = offset; 397 398 /* 399 * Insert it into the object_object/offset hash table 400 */ 401 402 bucket = &vm_page_buckets[vm_page_hash(object, offset)]; 403 simple_lock(&bucket_lock); 404 TAILQ_INSERT_TAIL(bucket, mem, hashq); 405 simple_unlock(&bucket_lock); 406 407 /* 408 * Now link into the object's list of backed pages. 409 */ 410 411 TAILQ_INSERT_TAIL(&object->memq, mem, listq); 412 mem->flags |= PG_TABLED; 413 414 /* 415 * And show that the object has one more resident page. 416 */ 417 418 object->resident_page_count++; 419 } 420 421 /* 422 * vm_page_remove: [ internal use only ] 423 * NOTE: used by device pager as well -wfj 424 * 425 * Removes the given mem entry from the object/offset-page 426 * table and the object page list. 427 * 428 * The object and page must be locked, and at splhigh. 429 */ 430 431 inline void 432 vm_page_remove(mem) 433 register vm_page_t mem; 434 { 435 register struct pglist *bucket; 436 437 VM_PAGE_CHECK(mem); 438 439 if (!(mem->flags & PG_TABLED)) 440 return; 441 442 /* 443 * Remove from the object_object/offset hash table 444 */ 445 446 bucket = &vm_page_buckets[vm_page_hash(mem->object, mem->offset)]; 447 simple_lock(&bucket_lock); 448 TAILQ_REMOVE(bucket, mem, hashq); 449 simple_unlock(&bucket_lock); 450 451 /* 452 * Now remove from the object's list of backed pages. 453 */ 454 455 TAILQ_REMOVE(&mem->object->memq, mem, listq); 456 457 /* 458 * And show that the object has one fewer resident page. 459 */ 460 461 mem->object->resident_page_count--; 462 463 mem->flags &= ~PG_TABLED; 464 } 465 466 /* 467 * vm_page_lookup: 468 * 469 * Returns the page associated with the object/offset 470 * pair specified; if none is found, NULL is returned. 471 * 472 * The object must be locked. No side effects. 473 */ 474 475 vm_page_t 476 vm_page_lookup(object, offset) 477 register vm_object_t object; 478 register vm_offset_t offset; 479 { 480 register vm_page_t mem; 481 register struct pglist *bucket; 482 int s; 483 484 /* 485 * Search the hash table for this object/offset pair 486 */ 487 488 bucket = &vm_page_buckets[vm_page_hash(object, offset)]; 489 490 s = splhigh(); 491 simple_lock(&bucket_lock); 492 for (mem = bucket->tqh_first; mem != NULL; mem = mem->hashq.tqe_next) { 493 VM_PAGE_CHECK(mem); 494 if ((mem->object == object) && (mem->offset == offset)) { 495 simple_unlock(&bucket_lock); 496 splx(s); 497 return (mem); 498 } 499 } 500 501 simple_unlock(&bucket_lock); 502 splx(s); 503 return (NULL); 504 } 505 506 /* 507 * vm_page_rename: 508 * 509 * Move the given memory entry from its 510 * current object to the specified target object/offset. 511 * 512 * The object must be locked. 513 */ 514 void 515 vm_page_rename(mem, new_object, new_offset) 516 register vm_page_t mem; 517 register vm_object_t new_object; 518 vm_offset_t new_offset; 519 { 520 int s; 521 522 if (mem->object == new_object) 523 return; 524 525 vm_page_lock_queues(); /* keep page from moving out from under pageout daemon */ 526 s = splhigh(); 527 vm_page_remove(mem); 528 vm_page_insert(mem, new_object, new_offset); 529 splx(s); 530 vm_page_unlock_queues(); 531 } 532 533 /* 534 * vm_page_unqueue must be called at splhigh(); 535 */ 536 inline void 537 vm_page_unqueue(vm_page_t mem) 538 { 539 int origflags; 540 541 origflags = mem->flags; 542 543 if ((origflags & (PG_ACTIVE|PG_INACTIVE|PG_CACHE)) == 0) 544 return; 545 546 if (origflags & PG_ACTIVE) { 547 TAILQ_REMOVE(&vm_page_queue_active, mem, pageq); 548 cnt.v_active_count--; 549 mem->flags &= ~PG_ACTIVE; 550 } else if (origflags & PG_INACTIVE) { 551 TAILQ_REMOVE(&vm_page_queue_inactive, mem, pageq); 552 cnt.v_inactive_count--; 553 mem->flags &= ~PG_INACTIVE; 554 } else if (origflags & PG_CACHE) { 555 TAILQ_REMOVE(&vm_page_queue_cache, mem, pageq); 556 cnt.v_cache_count--; 557 mem->flags &= ~PG_CACHE; 558 if (cnt.v_cache_count + cnt.v_free_count < cnt.v_free_reserved) 559 pagedaemon_wakeup(); 560 } 561 return; 562 } 563 564 /* 565 * vm_page_alloc: 566 * 567 * Allocate and return a memory cell associated 568 * with this VM object/offset pair. 569 * 570 * page_req classes: 571 * VM_ALLOC_NORMAL normal process request 572 * VM_ALLOC_SYSTEM system *really* needs a page 573 * VM_ALLOC_INTERRUPT interrupt time request 574 * 575 * Object must be locked. 576 */ 577 vm_page_t 578 vm_page_alloc(object, offset, page_req) 579 vm_object_t object; 580 vm_offset_t offset; 581 int page_req; 582 { 583 register vm_page_t mem; 584 int s; 585 586 if ((curproc == pageproc) && (page_req != VM_ALLOC_INTERRUPT)) { 587 page_req = VM_ALLOC_SYSTEM; 588 }; 589 590 simple_lock(&vm_page_queue_free_lock); 591 592 s = splhigh(); 593 594 mem = vm_page_queue_free.tqh_first; 595 596 switch (page_req) { 597 case VM_ALLOC_NORMAL: 598 if (cnt.v_free_count >= cnt.v_free_reserved) { 599 TAILQ_REMOVE(&vm_page_queue_free, mem, pageq); 600 cnt.v_free_count--; 601 } else { 602 mem = vm_page_queue_cache.tqh_first; 603 if (mem != NULL) { 604 TAILQ_REMOVE(&vm_page_queue_cache, mem, pageq); 605 vm_page_remove(mem); 606 cnt.v_cache_count--; 607 } else { 608 simple_unlock(&vm_page_queue_free_lock); 609 splx(s); 610 pagedaemon_wakeup(); 611 return (NULL); 612 } 613 } 614 break; 615 616 case VM_ALLOC_SYSTEM: 617 if ((cnt.v_free_count >= cnt.v_free_reserved) || 618 ((cnt.v_cache_count == 0) && 619 (cnt.v_free_count >= cnt.v_interrupt_free_min))) { 620 TAILQ_REMOVE(&vm_page_queue_free, mem, pageq); 621 cnt.v_free_count--; 622 } else { 623 mem = vm_page_queue_cache.tqh_first; 624 if (mem != NULL) { 625 TAILQ_REMOVE(&vm_page_queue_cache, mem, pageq); 626 vm_page_remove(mem); 627 cnt.v_cache_count--; 628 } else { 629 simple_unlock(&vm_page_queue_free_lock); 630 splx(s); 631 pagedaemon_wakeup(); 632 return (NULL); 633 } 634 } 635 break; 636 637 case VM_ALLOC_INTERRUPT: 638 if (mem != NULL) { 639 TAILQ_REMOVE(&vm_page_queue_free, mem, pageq); 640 cnt.v_free_count--; 641 } else { 642 simple_unlock(&vm_page_queue_free_lock); 643 splx(s); 644 pagedaemon_wakeup(); 645 return NULL; 646 } 647 break; 648 649 default: 650 panic("vm_page_alloc: invalid allocation class"); 651 } 652 653 simple_unlock(&vm_page_queue_free_lock); 654 655 mem->flags = PG_BUSY; 656 mem->wire_count = 0; 657 mem->hold_count = 0; 658 mem->act_count = 0; 659 mem->busy = 0; 660 mem->valid = 0; 661 mem->dirty = 0; 662 mem->bmapped = 0; 663 664 /* XXX before splx until vm_page_insert is safe */ 665 vm_page_insert(mem, object, offset); 666 667 splx(s); 668 669 /* 670 * Don't wakeup too often - wakeup the pageout daemon when 671 * we would be nearly out of memory. 672 */ 673 if (((cnt.v_free_count + cnt.v_cache_count) < cnt.v_free_min) || 674 (cnt.v_free_count < cnt.v_pageout_free_min)) 675 pagedaemon_wakeup(); 676 677 return (mem); 678 } 679 680 vm_offset_t 681 vm_page_alloc_contig(size, low, high, alignment) 682 vm_offset_t size; 683 vm_offset_t low; 684 vm_offset_t high; 685 vm_offset_t alignment; 686 { 687 int i, s, start; 688 vm_offset_t addr, phys, tmp_addr; 689 vm_page_t pga = vm_page_array; 690 691 if ((alignment & (alignment - 1)) != 0) 692 panic("vm_page_alloc_contig: alignment must be a power of 2"); 693 694 start = 0; 695 s = splhigh(); 696 again: 697 /* 698 * Find first page in array that is free, within range, and aligned. 699 */ 700 for (i = start; i < cnt.v_page_count; i++) { 701 phys = VM_PAGE_TO_PHYS(&pga[i]); 702 if (((pga[i].flags & PG_FREE) == PG_FREE) && 703 (phys >= low) && (phys < high) && 704 ((phys & (alignment - 1)) == 0)) 705 break; 706 } 707 708 /* 709 * If the above failed or we will exceed the upper bound, fail. 710 */ 711 if ((i == cnt.v_page_count) || ((VM_PAGE_TO_PHYS(&pga[i]) + size) > high)) { 712 splx(s); 713 return (NULL); 714 } 715 start = i; 716 717 /* 718 * Check successive pages for contiguous and free. 719 */ 720 for (i = start + 1; i < (start + size / PAGE_SIZE); i++) { 721 if ((VM_PAGE_TO_PHYS(&pga[i]) != 722 (VM_PAGE_TO_PHYS(&pga[i - 1]) + PAGE_SIZE)) || 723 ((pga[i].flags & PG_FREE) != PG_FREE)) { 724 start++; 725 goto again; 726 } 727 } 728 729 /* 730 * We've found a contiguous chunk that meets are requirements. 731 * Allocate kernel VM, unfree and assign the physical pages to it and 732 * return kernel VM pointer. 733 */ 734 tmp_addr = addr = kmem_alloc_pageable(kernel_map, size); 735 736 for (i = start; i < (start + size / PAGE_SIZE); i++) { 737 vm_page_t m = &pga[i]; 738 739 TAILQ_REMOVE(&vm_page_queue_free, m, pageq); 740 cnt.v_free_count--; 741 m->valid = VM_PAGE_BITS_ALL; 742 m->flags = 0; 743 m->dirty = 0; 744 m->wire_count = 0; 745 m->act_count = 0; 746 m->bmapped = 0; 747 m->busy = 0; 748 vm_page_insert(m, kernel_object, tmp_addr - VM_MIN_KERNEL_ADDRESS); 749 vm_page_wire(m); 750 pmap_kenter(tmp_addr, VM_PAGE_TO_PHYS(m)); 751 tmp_addr += PAGE_SIZE; 752 } 753 754 splx(s); 755 return (addr); 756 } 757 758 /* 759 * vm_page_free: 760 * 761 * Returns the given page to the free list, 762 * disassociating it with any VM object. 763 * 764 * Object and page must be locked prior to entry. 765 */ 766 void 767 vm_page_free(mem) 768 register vm_page_t mem; 769 { 770 int s; 771 int flags; 772 773 s = splhigh(); 774 vm_page_remove(mem); 775 vm_page_unqueue(mem); 776 777 flags = mem->flags; 778 if (mem->bmapped || mem->busy || flags & (PG_BUSY|PG_FREE)) { 779 if (flags & PG_FREE) 780 panic("vm_page_free: freeing free page"); 781 printf("vm_page_free: offset(%d), bmapped(%d), busy(%d), PG_BUSY(%d)\n", 782 mem->offset, mem->bmapped, mem->busy, (flags & PG_BUSY) ? 1 : 0); 783 panic("vm_page_free: freeing busy page"); 784 } 785 786 if ((flags & PG_WANTED) != 0) 787 wakeup((caddr_t) mem); 788 if ((flags & PG_FICTITIOUS) == 0) { 789 790 simple_lock(&vm_page_queue_free_lock); 791 if (mem->wire_count) { 792 if (mem->wire_count > 1) { 793 printf("vm_page_free: wire count > 1 (%d)", mem->wire_count); 794 panic("vm_page_free: invalid wire count"); 795 } 796 cnt.v_wire_count--; 797 mem->wire_count = 0; 798 } 799 mem->flags |= PG_FREE; 800 TAILQ_INSERT_TAIL(&vm_page_queue_free, mem, pageq); 801 802 simple_unlock(&vm_page_queue_free_lock); 803 splx(s); 804 /* 805 * if pageout daemon needs pages, then tell it that there are 806 * some free. 807 */ 808 if (vm_pageout_pages_needed) { 809 wakeup((caddr_t) &vm_pageout_pages_needed); 810 vm_pageout_pages_needed = 0; 811 } 812 813 cnt.v_free_count++; 814 /* 815 * wakeup processes that are waiting on memory if we hit a 816 * high water mark. And wakeup scheduler process if we have 817 * lots of memory. this process will swapin processes. 818 */ 819 if ((cnt.v_free_count + cnt.v_cache_count) == cnt.v_free_min) { 820 wakeup((caddr_t) &cnt.v_free_count); 821 wakeup((caddr_t) &proc0); 822 } 823 } else { 824 splx(s); 825 } 826 cnt.v_tfree++; 827 } 828 829 830 /* 831 * vm_page_wire: 832 * 833 * Mark this page as wired down by yet 834 * another map, removing it from paging queues 835 * as necessary. 836 * 837 * The page queues must be locked. 838 */ 839 void 840 vm_page_wire(mem) 841 register vm_page_t mem; 842 { 843 int s; 844 VM_PAGE_CHECK(mem); 845 846 if (mem->wire_count == 0) { 847 s = splhigh(); 848 vm_page_unqueue(mem); 849 splx(s); 850 cnt.v_wire_count++; 851 } 852 mem->flags |= PG_WRITEABLE|PG_MAPPED; 853 mem->wire_count++; 854 } 855 856 /* 857 * vm_page_unwire: 858 * 859 * Release one wiring of this page, potentially 860 * enabling it to be paged again. 861 * 862 * The page queues must be locked. 863 */ 864 void 865 vm_page_unwire(mem) 866 register vm_page_t mem; 867 { 868 int s; 869 870 VM_PAGE_CHECK(mem); 871 872 s = splhigh(); 873 874 if (mem->wire_count) 875 mem->wire_count--; 876 if (mem->wire_count == 0) { 877 TAILQ_INSERT_TAIL(&vm_page_queue_active, mem, pageq); 878 cnt.v_active_count++; 879 mem->flags |= PG_ACTIVE; 880 cnt.v_wire_count--; 881 } 882 splx(s); 883 } 884 885 /* 886 * vm_page_activate: 887 * 888 * Put the specified page on the active list (if appropriate). 889 * 890 * The page queues must be locked. 891 */ 892 void 893 vm_page_activate(m) 894 register vm_page_t m; 895 { 896 int s; 897 898 VM_PAGE_CHECK(m); 899 900 s = splhigh(); 901 if (m->flags & PG_ACTIVE) 902 panic("vm_page_activate: already active"); 903 904 if (m->flags & PG_CACHE) 905 cnt.v_reactivated++; 906 907 vm_page_unqueue(m); 908 909 if (m->wire_count == 0) { 910 TAILQ_INSERT_TAIL(&vm_page_queue_active, m, pageq); 911 m->flags |= PG_ACTIVE; 912 if (m->act_count < 5) 913 m->act_count = 5; 914 else if( m->act_count < ACT_MAX) 915 m->act_count += 1; 916 cnt.v_active_count++; 917 } 918 splx(s); 919 } 920 921 /* 922 * vm_page_deactivate: 923 * 924 * Returns the given page to the inactive list, 925 * indicating that no physical maps have access 926 * to this page. [Used by the physical mapping system.] 927 * 928 * The page queues must be locked. 929 */ 930 void 931 vm_page_deactivate(m) 932 register vm_page_t m; 933 { 934 int spl; 935 936 VM_PAGE_CHECK(m); 937 938 /* 939 * Only move active pages -- ignore locked or already inactive ones. 940 * 941 * XXX: sometimes we get pages which aren't wired down or on any queue - 942 * we need to put them on the inactive queue also, otherwise we lose 943 * track of them. Paul Mackerras (paulus@cs.anu.edu.au) 9-Jan-93. 944 */ 945 946 spl = splhigh(); 947 if (!(m->flags & PG_INACTIVE) && m->wire_count == 0 && 948 m->hold_count == 0) { 949 pmap_clear_reference(VM_PAGE_TO_PHYS(m)); 950 if (m->flags & PG_CACHE) 951 cnt.v_reactivated++; 952 vm_page_unqueue(m); 953 TAILQ_INSERT_TAIL(&vm_page_queue_inactive, m, pageq); 954 m->flags |= PG_INACTIVE; 955 cnt.v_inactive_count++; 956 m->act_count = 0; 957 } 958 splx(spl); 959 } 960 961 /* 962 * vm_page_cache 963 * 964 * Put the specified page onto the page cache queue (if appropriate). 965 */ 966 void 967 vm_page_cache(m) 968 register vm_page_t m; 969 { 970 int s; 971 972 VM_PAGE_CHECK(m); 973 if ((m->flags & (PG_CACHE | PG_BUSY)) || m->busy || m->wire_count || 974 m->bmapped) 975 return; 976 977 s = splhigh(); 978 vm_page_unqueue(m); 979 vm_page_protect(m, VM_PROT_NONE); 980 981 TAILQ_INSERT_TAIL(&vm_page_queue_cache, m, pageq); 982 m->flags |= PG_CACHE; 983 cnt.v_cache_count++; 984 if ((cnt.v_free_count + cnt.v_cache_count) == cnt.v_free_min) { 985 wakeup((caddr_t) &cnt.v_free_count); 986 wakeup((caddr_t) &proc0); 987 } 988 if (vm_pageout_pages_needed) { 989 wakeup((caddr_t) &vm_pageout_pages_needed); 990 vm_pageout_pages_needed = 0; 991 } 992 993 splx(s); 994 } 995 996 /* 997 * vm_page_zero_fill: 998 * 999 * Zero-fill the specified page. 1000 * Written as a standard pagein routine, to 1001 * be used by the zero-fill object. 1002 */ 1003 boolean_t 1004 vm_page_zero_fill(m) 1005 vm_page_t m; 1006 { 1007 VM_PAGE_CHECK(m); 1008 1009 pmap_zero_page(VM_PAGE_TO_PHYS(m)); 1010 m->valid = VM_PAGE_BITS_ALL; 1011 return (TRUE); 1012 } 1013 1014 /* 1015 * vm_page_copy: 1016 * 1017 * Copy one page to another 1018 */ 1019 void 1020 vm_page_copy(src_m, dest_m) 1021 vm_page_t src_m; 1022 vm_page_t dest_m; 1023 { 1024 VM_PAGE_CHECK(src_m); 1025 VM_PAGE_CHECK(dest_m); 1026 1027 pmap_copy_page(VM_PAGE_TO_PHYS(src_m), VM_PAGE_TO_PHYS(dest_m)); 1028 dest_m->valid = VM_PAGE_BITS_ALL; 1029 } 1030 1031 1032 /* 1033 * mapping function for valid bits or for dirty bits in 1034 * a page 1035 */ 1036 inline int 1037 vm_page_bits(int base, int size) 1038 { 1039 u_short chunk; 1040 1041 if ((base == 0) && (size >= PAGE_SIZE)) 1042 return VM_PAGE_BITS_ALL; 1043 size = (size + DEV_BSIZE - 1) & ~(DEV_BSIZE - 1); 1044 base = (base % PAGE_SIZE) / DEV_BSIZE; 1045 chunk = vm_page_dev_bsize_chunks[size / DEV_BSIZE]; 1046 return (chunk << base) & VM_PAGE_BITS_ALL; 1047 } 1048 1049 /* 1050 * set a page (partially) valid 1051 */ 1052 void 1053 vm_page_set_valid(m, base, size) 1054 vm_page_t m; 1055 int base; 1056 int size; 1057 { 1058 m->valid |= vm_page_bits(base, size); 1059 } 1060 1061 /* 1062 * set a page (partially) invalid 1063 */ 1064 void 1065 vm_page_set_invalid(m, base, size) 1066 vm_page_t m; 1067 int base; 1068 int size; 1069 { 1070 int bits; 1071 1072 m->valid &= ~(bits = vm_page_bits(base, size)); 1073 if (m->valid == 0) 1074 m->dirty &= ~bits; 1075 } 1076 1077 /* 1078 * is (partial) page valid? 1079 */ 1080 int 1081 vm_page_is_valid(m, base, size) 1082 vm_page_t m; 1083 int base; 1084 int size; 1085 { 1086 int bits = vm_page_bits(base, size); 1087 1088 if (m->valid && ((m->valid & bits) == bits)) 1089 return 1; 1090 else 1091 return 0; 1092 } 1093 1094 1095 /* 1096 * set a page (partially) dirty 1097 */ 1098 void 1099 vm_page_set_dirty(m, base, size) 1100 vm_page_t m; 1101 int base; 1102 int size; 1103 { 1104 if ((base != 0) || (size != PAGE_SIZE)) { 1105 if (pmap_is_modified(VM_PAGE_TO_PHYS(m))) { 1106 m->dirty = VM_PAGE_BITS_ALL; 1107 pmap_clear_modify(VM_PAGE_TO_PHYS(m)); 1108 return; 1109 } 1110 m->dirty |= vm_page_bits(base, size); 1111 } else { 1112 m->dirty = VM_PAGE_BITS_ALL; 1113 pmap_clear_modify(VM_PAGE_TO_PHYS(m)); 1114 } 1115 } 1116 1117 void 1118 vm_page_test_dirty(m) 1119 vm_page_t m; 1120 { 1121 if ((m->dirty != VM_PAGE_BITS_ALL) && 1122 pmap_is_modified(VM_PAGE_TO_PHYS(m))) { 1123 m->dirty = VM_PAGE_BITS_ALL; 1124 } 1125 } 1126 1127 /* 1128 * set a page (partially) clean 1129 */ 1130 void 1131 vm_page_set_clean(m, base, size) 1132 vm_page_t m; 1133 int base; 1134 int size; 1135 { 1136 m->dirty &= ~vm_page_bits(base, size); 1137 if( base == 0 && size == PAGE_SIZE) 1138 pmap_clear_modify(VM_PAGE_TO_PHYS(m)); 1139 } 1140 1141 /* 1142 * is (partial) page clean 1143 */ 1144 int 1145 vm_page_is_clean(m, base, size) 1146 vm_page_t m; 1147 int base; 1148 int size; 1149 { 1150 if (pmap_is_modified(VM_PAGE_TO_PHYS(m))) { 1151 m->dirty = VM_PAGE_BITS_ALL; 1152 pmap_clear_modify(VM_PAGE_TO_PHYS(m)); 1153 } 1154 if ((m->dirty & m->valid & vm_page_bits(base, size)) == 0) 1155 return 1; 1156 else 1157 return 0; 1158 } 1159 1160 #ifdef DDB 1161 void 1162 print_page_info() 1163 { 1164 printf("cnt.v_free_count: %d\n", cnt.v_free_count); 1165 printf("cnt.v_cache_count: %d\n", cnt.v_cache_count); 1166 printf("cnt.v_inactive_count: %d\n", cnt.v_inactive_count); 1167 printf("cnt.v_active_count: %d\n", cnt.v_active_count); 1168 printf("cnt.v_wire_count: %d\n", cnt.v_wire_count); 1169 printf("cnt.v_free_reserved: %d\n", cnt.v_free_reserved); 1170 printf("cnt.v_free_min: %d\n", cnt.v_free_min); 1171 printf("cnt.v_free_target: %d\n", cnt.v_free_target); 1172 printf("cnt.v_cache_min: %d\n", cnt.v_cache_min); 1173 printf("cnt.v_inactive_target: %d\n", cnt.v_inactive_target); 1174 } 1175 #endif 1176