1 /*- 2 * Copyright (c) 1991 Regents of the University of California. 3 * All rights reserved. 4 * Copyright (c) 1998 Matthew Dillon. All Rights Reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * The Mach Operating System project at Carnegie-Mellon University. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * from: @(#)vm_page.c 7.4 (Berkeley) 5/7/91 34 */ 35 36 /*- 37 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 38 * All rights reserved. 39 * 40 * Authors: Avadis Tevanian, Jr., Michael Wayne Young 41 * 42 * Permission to use, copy, modify and distribute this software and 43 * its documentation is hereby granted, provided that both the copyright 44 * notice and this permission notice appear in all copies of the 45 * software, derivative works or modified versions, and any portions 46 * thereof, and that both notices appear in supporting documentation. 47 * 48 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 49 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 50 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 51 * 52 * Carnegie Mellon requests users of this software to return to 53 * 54 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 55 * School of Computer Science 56 * Carnegie Mellon University 57 * Pittsburgh PA 15213-3890 58 * 59 * any improvements or extensions that they make and grant Carnegie the 60 * rights to redistribute these changes. 61 */ 62 63 /* 64 * GENERAL RULES ON VM_PAGE MANIPULATION 65 * 66 * - A page queue lock is required when adding or removing a page from a 67 * page queue regardless of other locks or the busy state of a page. 68 * 69 * * In general, no thread besides the page daemon can acquire or 70 * hold more than one page queue lock at a time. 71 * 72 * * The page daemon can acquire and hold any pair of page queue 73 * locks in any order. 74 * 75 * - The object lock is required when inserting or removing 76 * pages from an object (vm_page_insert() or vm_page_remove()). 77 * 78 */ 79 80 /* 81 * Resident memory management module. 82 */ 83 84 #include <sys/cdefs.h> 85 __FBSDID("$FreeBSD$"); 86 87 #include "opt_vm.h" 88 89 #include <sys/param.h> 90 #include <sys/systm.h> 91 #include <sys/lock.h> 92 #include <sys/kernel.h> 93 #include <sys/limits.h> 94 #include <sys/linker.h> 95 #include <sys/malloc.h> 96 #include <sys/mman.h> 97 #include <sys/msgbuf.h> 98 #include <sys/mutex.h> 99 #include <sys/proc.h> 100 #include <sys/rwlock.h> 101 #include <sys/sbuf.h> 102 #include <sys/sysctl.h> 103 #include <sys/vmmeter.h> 104 #include <sys/vnode.h> 105 106 #include <vm/vm.h> 107 #include <vm/pmap.h> 108 #include <vm/vm_param.h> 109 #include <vm/vm_kern.h> 110 #include <vm/vm_object.h> 111 #include <vm/vm_page.h> 112 #include <vm/vm_pageout.h> 113 #include <vm/vm_pager.h> 114 #include <vm/vm_phys.h> 115 #include <vm/vm_radix.h> 116 #include <vm/vm_reserv.h> 117 #include <vm/vm_extern.h> 118 #include <vm/uma.h> 119 #include <vm/uma_int.h> 120 121 #include <machine/md_var.h> 122 123 /* 124 * Associated with page of user-allocatable memory is a 125 * page structure. 126 */ 127 128 struct vm_domain vm_dom[MAXMEMDOM]; 129 struct mtx_padalign vm_page_queue_free_mtx; 130 131 struct mtx_padalign pa_lock[PA_LOCK_COUNT]; 132 133 vm_page_t vm_page_array; 134 long vm_page_array_size; 135 long first_page; 136 int vm_page_zero_count; 137 138 static int boot_pages = UMA_BOOT_PAGES; 139 SYSCTL_INT(_vm, OID_AUTO, boot_pages, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, 140 &boot_pages, 0, 141 "number of pages allocated for bootstrapping the VM system"); 142 143 static int pa_tryrelock_restart; 144 SYSCTL_INT(_vm, OID_AUTO, tryrelock_restart, CTLFLAG_RD, 145 &pa_tryrelock_restart, 0, "Number of tryrelock restarts"); 146 147 static TAILQ_HEAD(, vm_page) blacklist_head; 148 static int sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS); 149 SYSCTL_PROC(_vm, OID_AUTO, page_blacklist, CTLTYPE_STRING | CTLFLAG_RD | 150 CTLFLAG_MPSAFE, NULL, 0, sysctl_vm_page_blacklist, "A", "Blacklist pages"); 151 152 /* Is the page daemon waiting for free pages? */ 153 static int vm_pageout_pages_needed; 154 155 static uma_zone_t fakepg_zone; 156 157 static struct vnode *vm_page_alloc_init(vm_page_t m); 158 static void vm_page_cache_turn_free(vm_page_t m); 159 static void vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits); 160 static void vm_page_enqueue(uint8_t queue, vm_page_t m); 161 static void vm_page_free_wakeup(void); 162 static void vm_page_init_fakepg(void *dummy); 163 static int vm_page_insert_after(vm_page_t m, vm_object_t object, 164 vm_pindex_t pindex, vm_page_t mpred); 165 static void vm_page_insert_radixdone(vm_page_t m, vm_object_t object, 166 vm_page_t mpred); 167 static int vm_page_reclaim_run(int req_class, u_long npages, vm_page_t m_run, 168 vm_paddr_t high); 169 170 SYSINIT(vm_page, SI_SUB_VM, SI_ORDER_SECOND, vm_page_init_fakepg, NULL); 171 172 static void 173 vm_page_init_fakepg(void *dummy) 174 { 175 176 fakepg_zone = uma_zcreate("fakepg", sizeof(struct vm_page), NULL, NULL, 177 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE | UMA_ZONE_VM); 178 } 179 180 /* Make sure that u_long is at least 64 bits when PAGE_SIZE is 32K. */ 181 #if PAGE_SIZE == 32768 182 #ifdef CTASSERT 183 CTASSERT(sizeof(u_long) >= 8); 184 #endif 185 #endif 186 187 /* 188 * Try to acquire a physical address lock while a pmap is locked. If we 189 * fail to trylock we unlock and lock the pmap directly and cache the 190 * locked pa in *locked. The caller should then restart their loop in case 191 * the virtual to physical mapping has changed. 192 */ 193 int 194 vm_page_pa_tryrelock(pmap_t pmap, vm_paddr_t pa, vm_paddr_t *locked) 195 { 196 vm_paddr_t lockpa; 197 198 lockpa = *locked; 199 *locked = pa; 200 if (lockpa) { 201 PA_LOCK_ASSERT(lockpa, MA_OWNED); 202 if (PA_LOCKPTR(pa) == PA_LOCKPTR(lockpa)) 203 return (0); 204 PA_UNLOCK(lockpa); 205 } 206 if (PA_TRYLOCK(pa)) 207 return (0); 208 PMAP_UNLOCK(pmap); 209 atomic_add_int(&pa_tryrelock_restart, 1); 210 PA_LOCK(pa); 211 PMAP_LOCK(pmap); 212 return (EAGAIN); 213 } 214 215 /* 216 * vm_set_page_size: 217 * 218 * Sets the page size, perhaps based upon the memory 219 * size. Must be called before any use of page-size 220 * dependent functions. 221 */ 222 void 223 vm_set_page_size(void) 224 { 225 if (vm_cnt.v_page_size == 0) 226 vm_cnt.v_page_size = PAGE_SIZE; 227 if (((vm_cnt.v_page_size - 1) & vm_cnt.v_page_size) != 0) 228 panic("vm_set_page_size: page size not a power of two"); 229 } 230 231 /* 232 * vm_page_blacklist_next: 233 * 234 * Find the next entry in the provided string of blacklist 235 * addresses. Entries are separated by space, comma, or newline. 236 * If an invalid integer is encountered then the rest of the 237 * string is skipped. Updates the list pointer to the next 238 * character, or NULL if the string is exhausted or invalid. 239 */ 240 static vm_paddr_t 241 vm_page_blacklist_next(char **list, char *end) 242 { 243 vm_paddr_t bad; 244 char *cp, *pos; 245 246 if (list == NULL || *list == NULL) 247 return (0); 248 if (**list =='\0') { 249 *list = NULL; 250 return (0); 251 } 252 253 /* 254 * If there's no end pointer then the buffer is coming from 255 * the kenv and we know it's null-terminated. 256 */ 257 if (end == NULL) 258 end = *list + strlen(*list); 259 260 /* Ensure that strtoq() won't walk off the end */ 261 if (*end != '\0') { 262 if (*end == '\n' || *end == ' ' || *end == ',') 263 *end = '\0'; 264 else { 265 printf("Blacklist not terminated, skipping\n"); 266 *list = NULL; 267 return (0); 268 } 269 } 270 271 for (pos = *list; *pos != '\0'; pos = cp) { 272 bad = strtoq(pos, &cp, 0); 273 if (*cp == '\0' || *cp == ' ' || *cp == ',' || *cp == '\n') { 274 if (bad == 0) { 275 if (++cp < end) 276 continue; 277 else 278 break; 279 } 280 } else 281 break; 282 if (*cp == '\0' || ++cp >= end) 283 *list = NULL; 284 else 285 *list = cp; 286 return (trunc_page(bad)); 287 } 288 printf("Garbage in RAM blacklist, skipping\n"); 289 *list = NULL; 290 return (0); 291 } 292 293 /* 294 * vm_page_blacklist_check: 295 * 296 * Iterate through the provided string of blacklist addresses, pulling 297 * each entry out of the physical allocator free list and putting it 298 * onto a list for reporting via the vm.page_blacklist sysctl. 299 */ 300 static void 301 vm_page_blacklist_check(char *list, char *end) 302 { 303 vm_paddr_t pa; 304 vm_page_t m; 305 char *next; 306 int ret; 307 308 next = list; 309 while (next != NULL) { 310 if ((pa = vm_page_blacklist_next(&next, end)) == 0) 311 continue; 312 m = vm_phys_paddr_to_vm_page(pa); 313 if (m == NULL) 314 continue; 315 mtx_lock(&vm_page_queue_free_mtx); 316 ret = vm_phys_unfree_page(m); 317 mtx_unlock(&vm_page_queue_free_mtx); 318 if (ret == TRUE) { 319 TAILQ_INSERT_TAIL(&blacklist_head, m, listq); 320 if (bootverbose) 321 printf("Skipping page with pa 0x%jx\n", 322 (uintmax_t)pa); 323 } 324 } 325 } 326 327 /* 328 * vm_page_blacklist_load: 329 * 330 * Search for a special module named "ram_blacklist". It'll be a 331 * plain text file provided by the user via the loader directive 332 * of the same name. 333 */ 334 static void 335 vm_page_blacklist_load(char **list, char **end) 336 { 337 void *mod; 338 u_char *ptr; 339 u_int len; 340 341 mod = NULL; 342 ptr = NULL; 343 344 mod = preload_search_by_type("ram_blacklist"); 345 if (mod != NULL) { 346 ptr = preload_fetch_addr(mod); 347 len = preload_fetch_size(mod); 348 } 349 *list = ptr; 350 if (ptr != NULL) 351 *end = ptr + len; 352 else 353 *end = NULL; 354 return; 355 } 356 357 static int 358 sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS) 359 { 360 vm_page_t m; 361 struct sbuf sbuf; 362 int error, first; 363 364 first = 1; 365 error = sysctl_wire_old_buffer(req, 0); 366 if (error != 0) 367 return (error); 368 sbuf_new_for_sysctl(&sbuf, NULL, 128, req); 369 TAILQ_FOREACH(m, &blacklist_head, listq) { 370 sbuf_printf(&sbuf, "%s%#jx", first ? "" : ",", 371 (uintmax_t)m->phys_addr); 372 first = 0; 373 } 374 error = sbuf_finish(&sbuf); 375 sbuf_delete(&sbuf); 376 return (error); 377 } 378 379 static void 380 vm_page_domain_init(struct vm_domain *vmd) 381 { 382 struct vm_pagequeue *pq; 383 int i; 384 385 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_INACTIVE].pq_name) = 386 "vm inactive pagequeue"; 387 *__DECONST(u_int **, &vmd->vmd_pagequeues[PQ_INACTIVE].pq_vcnt) = 388 &vm_cnt.v_inactive_count; 389 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_ACTIVE].pq_name) = 390 "vm active pagequeue"; 391 *__DECONST(u_int **, &vmd->vmd_pagequeues[PQ_ACTIVE].pq_vcnt) = 392 &vm_cnt.v_active_count; 393 vmd->vmd_page_count = 0; 394 vmd->vmd_free_count = 0; 395 vmd->vmd_segs = 0; 396 vmd->vmd_oom = FALSE; 397 vmd->vmd_pass = 0; 398 for (i = 0; i < PQ_COUNT; i++) { 399 pq = &vmd->vmd_pagequeues[i]; 400 TAILQ_INIT(&pq->pq_pl); 401 mtx_init(&pq->pq_mutex, pq->pq_name, "vm pagequeue", 402 MTX_DEF | MTX_DUPOK); 403 } 404 } 405 406 /* 407 * vm_page_startup: 408 * 409 * Initializes the resident memory module. 410 * 411 * Allocates memory for the page cells, and 412 * for the object/offset-to-page hash table headers. 413 * Each page cell is initialized and placed on the free list. 414 */ 415 vm_offset_t 416 vm_page_startup(vm_offset_t vaddr) 417 { 418 vm_offset_t mapped; 419 vm_paddr_t page_range; 420 vm_paddr_t new_end; 421 int i; 422 vm_paddr_t pa; 423 vm_paddr_t last_pa; 424 char *list, *listend; 425 vm_paddr_t end; 426 vm_paddr_t biggestsize; 427 vm_paddr_t low_water, high_water; 428 int biggestone; 429 430 biggestsize = 0; 431 biggestone = 0; 432 vaddr = round_page(vaddr); 433 434 for (i = 0; phys_avail[i + 1]; i += 2) { 435 phys_avail[i] = round_page(phys_avail[i]); 436 phys_avail[i + 1] = trunc_page(phys_avail[i + 1]); 437 } 438 439 low_water = phys_avail[0]; 440 high_water = phys_avail[1]; 441 442 for (i = 0; i < vm_phys_nsegs; i++) { 443 if (vm_phys_segs[i].start < low_water) 444 low_water = vm_phys_segs[i].start; 445 if (vm_phys_segs[i].end > high_water) 446 high_water = vm_phys_segs[i].end; 447 } 448 for (i = 0; phys_avail[i + 1]; i += 2) { 449 vm_paddr_t size = phys_avail[i + 1] - phys_avail[i]; 450 451 if (size > biggestsize) { 452 biggestone = i; 453 biggestsize = size; 454 } 455 if (phys_avail[i] < low_water) 456 low_water = phys_avail[i]; 457 if (phys_avail[i + 1] > high_water) 458 high_water = phys_avail[i + 1]; 459 } 460 461 end = phys_avail[biggestone+1]; 462 463 /* 464 * Initialize the page and queue locks. 465 */ 466 mtx_init(&vm_page_queue_free_mtx, "vm page free queue", NULL, MTX_DEF); 467 for (i = 0; i < PA_LOCK_COUNT; i++) 468 mtx_init(&pa_lock[i], "vm page", NULL, MTX_DEF); 469 for (i = 0; i < vm_ndomains; i++) 470 vm_page_domain_init(&vm_dom[i]); 471 472 /* 473 * Allocate memory for use when boot strapping the kernel memory 474 * allocator. 475 * 476 * CTFLAG_RDTUN doesn't work during the early boot process, so we must 477 * manually fetch the value. 478 */ 479 TUNABLE_INT_FETCH("vm.boot_pages", &boot_pages); 480 new_end = end - (boot_pages * UMA_SLAB_SIZE); 481 new_end = trunc_page(new_end); 482 mapped = pmap_map(&vaddr, new_end, end, 483 VM_PROT_READ | VM_PROT_WRITE); 484 bzero((void *)mapped, end - new_end); 485 uma_startup((void *)mapped, boot_pages); 486 487 #if defined(__aarch64__) || defined(__amd64__) || defined(__arm__) || \ 488 defined(__i386__) || defined(__mips__) 489 /* 490 * Allocate a bitmap to indicate that a random physical page 491 * needs to be included in a minidump. 492 * 493 * The amd64 port needs this to indicate which direct map pages 494 * need to be dumped, via calls to dump_add_page()/dump_drop_page(). 495 * 496 * However, i386 still needs this workspace internally within the 497 * minidump code. In theory, they are not needed on i386, but are 498 * included should the sf_buf code decide to use them. 499 */ 500 last_pa = 0; 501 for (i = 0; dump_avail[i + 1] != 0; i += 2) 502 if (dump_avail[i + 1] > last_pa) 503 last_pa = dump_avail[i + 1]; 504 page_range = last_pa / PAGE_SIZE; 505 vm_page_dump_size = round_page(roundup2(page_range, NBBY) / NBBY); 506 new_end -= vm_page_dump_size; 507 vm_page_dump = (void *)(uintptr_t)pmap_map(&vaddr, new_end, 508 new_end + vm_page_dump_size, VM_PROT_READ | VM_PROT_WRITE); 509 bzero((void *)vm_page_dump, vm_page_dump_size); 510 #endif 511 #ifdef __amd64__ 512 /* 513 * Request that the physical pages underlying the message buffer be 514 * included in a crash dump. Since the message buffer is accessed 515 * through the direct map, they are not automatically included. 516 */ 517 pa = DMAP_TO_PHYS((vm_offset_t)msgbufp->msg_ptr); 518 last_pa = pa + round_page(msgbufsize); 519 while (pa < last_pa) { 520 dump_add_page(pa); 521 pa += PAGE_SIZE; 522 } 523 #endif 524 /* 525 * Compute the number of pages of memory that will be available for 526 * use (taking into account the overhead of a page structure per 527 * page). 528 */ 529 first_page = low_water / PAGE_SIZE; 530 #ifdef VM_PHYSSEG_SPARSE 531 page_range = 0; 532 for (i = 0; i < vm_phys_nsegs; i++) { 533 page_range += atop(vm_phys_segs[i].end - 534 vm_phys_segs[i].start); 535 } 536 for (i = 0; phys_avail[i + 1] != 0; i += 2) 537 page_range += atop(phys_avail[i + 1] - phys_avail[i]); 538 #elif defined(VM_PHYSSEG_DENSE) 539 page_range = high_water / PAGE_SIZE - first_page; 540 #else 541 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." 542 #endif 543 end = new_end; 544 545 /* 546 * Reserve an unmapped guard page to trap access to vm_page_array[-1]. 547 */ 548 vaddr += PAGE_SIZE; 549 550 /* 551 * Initialize the mem entry structures now, and put them in the free 552 * queue. 553 */ 554 new_end = trunc_page(end - page_range * sizeof(struct vm_page)); 555 mapped = pmap_map(&vaddr, new_end, end, 556 VM_PROT_READ | VM_PROT_WRITE); 557 vm_page_array = (vm_page_t) mapped; 558 #if VM_NRESERVLEVEL > 0 559 /* 560 * Allocate memory for the reservation management system's data 561 * structures. 562 */ 563 new_end = vm_reserv_startup(&vaddr, new_end, high_water); 564 #endif 565 #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) 566 /* 567 * pmap_map on arm64, amd64, and mips can come out of the direct-map, 568 * not kvm like i386, so the pages must be tracked for a crashdump to 569 * include this data. This includes the vm_page_array and the early 570 * UMA bootstrap pages. 571 */ 572 for (pa = new_end; pa < phys_avail[biggestone + 1]; pa += PAGE_SIZE) 573 dump_add_page(pa); 574 #endif 575 phys_avail[biggestone + 1] = new_end; 576 577 /* 578 * Add physical memory segments corresponding to the available 579 * physical pages. 580 */ 581 for (i = 0; phys_avail[i + 1] != 0; i += 2) 582 vm_phys_add_seg(phys_avail[i], phys_avail[i + 1]); 583 584 /* 585 * Clear all of the page structures 586 */ 587 bzero((caddr_t) vm_page_array, page_range * sizeof(struct vm_page)); 588 for (i = 0; i < page_range; i++) 589 vm_page_array[i].order = VM_NFREEORDER; 590 vm_page_array_size = page_range; 591 592 /* 593 * Initialize the physical memory allocator. 594 */ 595 vm_phys_init(); 596 597 /* 598 * Add every available physical page that is not blacklisted to 599 * the free lists. 600 */ 601 vm_cnt.v_page_count = 0; 602 vm_cnt.v_free_count = 0; 603 for (i = 0; phys_avail[i + 1] != 0; i += 2) { 604 pa = phys_avail[i]; 605 last_pa = phys_avail[i + 1]; 606 while (pa < last_pa) { 607 vm_phys_add_page(pa); 608 pa += PAGE_SIZE; 609 } 610 } 611 612 TAILQ_INIT(&blacklist_head); 613 vm_page_blacklist_load(&list, &listend); 614 vm_page_blacklist_check(list, listend); 615 616 list = kern_getenv("vm.blacklist"); 617 vm_page_blacklist_check(list, NULL); 618 619 freeenv(list); 620 #if VM_NRESERVLEVEL > 0 621 /* 622 * Initialize the reservation management system. 623 */ 624 vm_reserv_init(); 625 #endif 626 return (vaddr); 627 } 628 629 void 630 vm_page_reference(vm_page_t m) 631 { 632 633 vm_page_aflag_set(m, PGA_REFERENCED); 634 } 635 636 /* 637 * vm_page_busy_downgrade: 638 * 639 * Downgrade an exclusive busy page into a single shared busy page. 640 */ 641 void 642 vm_page_busy_downgrade(vm_page_t m) 643 { 644 u_int x; 645 646 vm_page_assert_xbusied(m); 647 648 for (;;) { 649 x = m->busy_lock; 650 x &= VPB_BIT_WAITERS; 651 if (atomic_cmpset_rel_int(&m->busy_lock, 652 VPB_SINGLE_EXCLUSIVER | x, VPB_SHARERS_WORD(1) | x)) 653 break; 654 } 655 } 656 657 /* 658 * vm_page_sbusied: 659 * 660 * Return a positive value if the page is shared busied, 0 otherwise. 661 */ 662 int 663 vm_page_sbusied(vm_page_t m) 664 { 665 u_int x; 666 667 x = m->busy_lock; 668 return ((x & VPB_BIT_SHARED) != 0 && x != VPB_UNBUSIED); 669 } 670 671 /* 672 * vm_page_sunbusy: 673 * 674 * Shared unbusy a page. 675 */ 676 void 677 vm_page_sunbusy(vm_page_t m) 678 { 679 u_int x; 680 681 vm_page_assert_sbusied(m); 682 683 for (;;) { 684 x = m->busy_lock; 685 if (VPB_SHARERS(x) > 1) { 686 if (atomic_cmpset_int(&m->busy_lock, x, 687 x - VPB_ONE_SHARER)) 688 break; 689 continue; 690 } 691 if ((x & VPB_BIT_WAITERS) == 0) { 692 KASSERT(x == VPB_SHARERS_WORD(1), 693 ("vm_page_sunbusy: invalid lock state")); 694 if (atomic_cmpset_int(&m->busy_lock, 695 VPB_SHARERS_WORD(1), VPB_UNBUSIED)) 696 break; 697 continue; 698 } 699 KASSERT(x == (VPB_SHARERS_WORD(1) | VPB_BIT_WAITERS), 700 ("vm_page_sunbusy: invalid lock state for waiters")); 701 702 vm_page_lock(m); 703 if (!atomic_cmpset_int(&m->busy_lock, x, VPB_UNBUSIED)) { 704 vm_page_unlock(m); 705 continue; 706 } 707 wakeup(m); 708 vm_page_unlock(m); 709 break; 710 } 711 } 712 713 /* 714 * vm_page_busy_sleep: 715 * 716 * Sleep and release the page lock, using the page pointer as wchan. 717 * This is used to implement the hard-path of busying mechanism. 718 * 719 * The given page must be locked. 720 */ 721 void 722 vm_page_busy_sleep(vm_page_t m, const char *wmesg) 723 { 724 u_int x; 725 726 vm_page_lock_assert(m, MA_OWNED); 727 728 x = m->busy_lock; 729 if (x == VPB_UNBUSIED) { 730 vm_page_unlock(m); 731 return; 732 } 733 if ((x & VPB_BIT_WAITERS) == 0 && 734 !atomic_cmpset_int(&m->busy_lock, x, x | VPB_BIT_WAITERS)) { 735 vm_page_unlock(m); 736 return; 737 } 738 msleep(m, vm_page_lockptr(m), PVM | PDROP, wmesg, 0); 739 } 740 741 /* 742 * vm_page_trysbusy: 743 * 744 * Try to shared busy a page. 745 * If the operation succeeds 1 is returned otherwise 0. 746 * The operation never sleeps. 747 */ 748 int 749 vm_page_trysbusy(vm_page_t m) 750 { 751 u_int x; 752 753 for (;;) { 754 x = m->busy_lock; 755 if ((x & VPB_BIT_SHARED) == 0) 756 return (0); 757 if (atomic_cmpset_acq_int(&m->busy_lock, x, x + VPB_ONE_SHARER)) 758 return (1); 759 } 760 } 761 762 static void 763 vm_page_xunbusy_maybelocked(vm_page_t m) 764 { 765 bool lockacq; 766 767 vm_page_assert_xbusied(m); 768 769 lockacq = !mtx_owned(vm_page_lockptr(m)); 770 if (lockacq) 771 vm_page_lock(m); 772 vm_page_flash(m); 773 atomic_store_rel_int(&m->busy_lock, VPB_UNBUSIED); 774 if (lockacq) 775 vm_page_unlock(m); 776 } 777 778 /* 779 * vm_page_xunbusy_hard: 780 * 781 * Called after the first try the exclusive unbusy of a page failed. 782 * It is assumed that the waiters bit is on. 783 */ 784 void 785 vm_page_xunbusy_hard(vm_page_t m) 786 { 787 788 vm_page_assert_xbusied(m); 789 790 vm_page_lock(m); 791 atomic_store_rel_int(&m->busy_lock, VPB_UNBUSIED); 792 wakeup(m); 793 vm_page_unlock(m); 794 } 795 796 /* 797 * vm_page_flash: 798 * 799 * Wakeup anyone waiting for the page. 800 * The ownership bits do not change. 801 * 802 * The given page must be locked. 803 */ 804 void 805 vm_page_flash(vm_page_t m) 806 { 807 u_int x; 808 809 vm_page_lock_assert(m, MA_OWNED); 810 811 for (;;) { 812 x = m->busy_lock; 813 if ((x & VPB_BIT_WAITERS) == 0) 814 return; 815 if (atomic_cmpset_int(&m->busy_lock, x, 816 x & (~VPB_BIT_WAITERS))) 817 break; 818 } 819 wakeup(m); 820 } 821 822 /* 823 * Keep page from being freed by the page daemon 824 * much of the same effect as wiring, except much lower 825 * overhead and should be used only for *very* temporary 826 * holding ("wiring"). 827 */ 828 void 829 vm_page_hold(vm_page_t mem) 830 { 831 832 vm_page_lock_assert(mem, MA_OWNED); 833 mem->hold_count++; 834 } 835 836 void 837 vm_page_unhold(vm_page_t mem) 838 { 839 840 vm_page_lock_assert(mem, MA_OWNED); 841 KASSERT(mem->hold_count >= 1, ("vm_page_unhold: hold count < 0!!!")); 842 --mem->hold_count; 843 if (mem->hold_count == 0 && (mem->flags & PG_UNHOLDFREE) != 0) 844 vm_page_free_toq(mem); 845 } 846 847 /* 848 * vm_page_unhold_pages: 849 * 850 * Unhold each of the pages that is referenced by the given array. 851 */ 852 void 853 vm_page_unhold_pages(vm_page_t *ma, int count) 854 { 855 struct mtx *mtx, *new_mtx; 856 857 mtx = NULL; 858 for (; count != 0; count--) { 859 /* 860 * Avoid releasing and reacquiring the same page lock. 861 */ 862 new_mtx = vm_page_lockptr(*ma); 863 if (mtx != new_mtx) { 864 if (mtx != NULL) 865 mtx_unlock(mtx); 866 mtx = new_mtx; 867 mtx_lock(mtx); 868 } 869 vm_page_unhold(*ma); 870 ma++; 871 } 872 if (mtx != NULL) 873 mtx_unlock(mtx); 874 } 875 876 vm_page_t 877 PHYS_TO_VM_PAGE(vm_paddr_t pa) 878 { 879 vm_page_t m; 880 881 #ifdef VM_PHYSSEG_SPARSE 882 m = vm_phys_paddr_to_vm_page(pa); 883 if (m == NULL) 884 m = vm_phys_fictitious_to_vm_page(pa); 885 return (m); 886 #elif defined(VM_PHYSSEG_DENSE) 887 long pi; 888 889 pi = atop(pa); 890 if (pi >= first_page && (pi - first_page) < vm_page_array_size) { 891 m = &vm_page_array[pi - first_page]; 892 return (m); 893 } 894 return (vm_phys_fictitious_to_vm_page(pa)); 895 #else 896 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." 897 #endif 898 } 899 900 /* 901 * vm_page_getfake: 902 * 903 * Create a fictitious page with the specified physical address and 904 * memory attribute. The memory attribute is the only the machine- 905 * dependent aspect of a fictitious page that must be initialized. 906 */ 907 vm_page_t 908 vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr) 909 { 910 vm_page_t m; 911 912 m = uma_zalloc(fakepg_zone, M_WAITOK | M_ZERO); 913 vm_page_initfake(m, paddr, memattr); 914 return (m); 915 } 916 917 void 918 vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) 919 { 920 921 if ((m->flags & PG_FICTITIOUS) != 0) { 922 /* 923 * The page's memattr might have changed since the 924 * previous initialization. Update the pmap to the 925 * new memattr. 926 */ 927 goto memattr; 928 } 929 m->phys_addr = paddr; 930 m->queue = PQ_NONE; 931 /* Fictitious pages don't use "segind". */ 932 m->flags = PG_FICTITIOUS; 933 /* Fictitious pages don't use "order" or "pool". */ 934 m->oflags = VPO_UNMANAGED; 935 m->busy_lock = VPB_SINGLE_EXCLUSIVER; 936 m->wire_count = 1; 937 pmap_page_init(m); 938 memattr: 939 pmap_page_set_memattr(m, memattr); 940 } 941 942 /* 943 * vm_page_putfake: 944 * 945 * Release a fictitious page. 946 */ 947 void 948 vm_page_putfake(vm_page_t m) 949 { 950 951 KASSERT((m->oflags & VPO_UNMANAGED) != 0, ("managed %p", m)); 952 KASSERT((m->flags & PG_FICTITIOUS) != 0, 953 ("vm_page_putfake: bad page %p", m)); 954 uma_zfree(fakepg_zone, m); 955 } 956 957 /* 958 * vm_page_updatefake: 959 * 960 * Update the given fictitious page to the specified physical address and 961 * memory attribute. 962 */ 963 void 964 vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) 965 { 966 967 KASSERT((m->flags & PG_FICTITIOUS) != 0, 968 ("vm_page_updatefake: bad page %p", m)); 969 m->phys_addr = paddr; 970 pmap_page_set_memattr(m, memattr); 971 } 972 973 /* 974 * vm_page_free: 975 * 976 * Free a page. 977 */ 978 void 979 vm_page_free(vm_page_t m) 980 { 981 982 m->flags &= ~PG_ZERO; 983 vm_page_free_toq(m); 984 } 985 986 /* 987 * vm_page_free_zero: 988 * 989 * Free a page to the zerod-pages queue 990 */ 991 void 992 vm_page_free_zero(vm_page_t m) 993 { 994 995 m->flags |= PG_ZERO; 996 vm_page_free_toq(m); 997 } 998 999 /* 1000 * Unbusy and handle the page queueing for a page from the VOP_GETPAGES() 1001 * array which was optionally read ahead or behind. 1002 */ 1003 void 1004 vm_page_readahead_finish(vm_page_t m) 1005 { 1006 1007 /* We shouldn't put invalid pages on queues. */ 1008 KASSERT(m->valid != 0, ("%s: %p is invalid", __func__, m)); 1009 1010 /* 1011 * Since the page is not the actually needed one, whether it should 1012 * be activated or deactivated is not obvious. Empirical results 1013 * have shown that deactivating the page is usually the best choice, 1014 * unless the page is wanted by another thread. 1015 */ 1016 vm_page_lock(m); 1017 if ((m->busy_lock & VPB_BIT_WAITERS) != 0) 1018 vm_page_activate(m); 1019 else 1020 vm_page_deactivate(m); 1021 vm_page_unlock(m); 1022 vm_page_xunbusy(m); 1023 } 1024 1025 /* 1026 * vm_page_sleep_if_busy: 1027 * 1028 * Sleep and release the page queues lock if the page is busied. 1029 * Returns TRUE if the thread slept. 1030 * 1031 * The given page must be unlocked and object containing it must 1032 * be locked. 1033 */ 1034 int 1035 vm_page_sleep_if_busy(vm_page_t m, const char *msg) 1036 { 1037 vm_object_t obj; 1038 1039 vm_page_lock_assert(m, MA_NOTOWNED); 1040 VM_OBJECT_ASSERT_WLOCKED(m->object); 1041 1042 if (vm_page_busied(m)) { 1043 /* 1044 * The page-specific object must be cached because page 1045 * identity can change during the sleep, causing the 1046 * re-lock of a different object. 1047 * It is assumed that a reference to the object is already 1048 * held by the callers. 1049 */ 1050 obj = m->object; 1051 vm_page_lock(m); 1052 VM_OBJECT_WUNLOCK(obj); 1053 vm_page_busy_sleep(m, msg); 1054 VM_OBJECT_WLOCK(obj); 1055 return (TRUE); 1056 } 1057 return (FALSE); 1058 } 1059 1060 /* 1061 * vm_page_dirty_KBI: [ internal use only ] 1062 * 1063 * Set all bits in the page's dirty field. 1064 * 1065 * The object containing the specified page must be locked if the 1066 * call is made from the machine-independent layer. 1067 * 1068 * See vm_page_clear_dirty_mask(). 1069 * 1070 * This function should only be called by vm_page_dirty(). 1071 */ 1072 void 1073 vm_page_dirty_KBI(vm_page_t m) 1074 { 1075 1076 /* These assertions refer to this operation by its public name. */ 1077 KASSERT((m->flags & PG_CACHED) == 0, 1078 ("vm_page_dirty: page in cache!")); 1079 KASSERT(m->valid == VM_PAGE_BITS_ALL, 1080 ("vm_page_dirty: page is invalid!")); 1081 m->dirty = VM_PAGE_BITS_ALL; 1082 } 1083 1084 /* 1085 * vm_page_insert: [ internal use only ] 1086 * 1087 * Inserts the given mem entry into the object and object list. 1088 * 1089 * The object must be locked. 1090 */ 1091 int 1092 vm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex) 1093 { 1094 vm_page_t mpred; 1095 1096 VM_OBJECT_ASSERT_WLOCKED(object); 1097 mpred = vm_radix_lookup_le(&object->rtree, pindex); 1098 return (vm_page_insert_after(m, object, pindex, mpred)); 1099 } 1100 1101 /* 1102 * vm_page_insert_after: 1103 * 1104 * Inserts the page "m" into the specified object at offset "pindex". 1105 * 1106 * The page "mpred" must immediately precede the offset "pindex" within 1107 * the specified object. 1108 * 1109 * The object must be locked. 1110 */ 1111 static int 1112 vm_page_insert_after(vm_page_t m, vm_object_t object, vm_pindex_t pindex, 1113 vm_page_t mpred) 1114 { 1115 vm_page_t msucc; 1116 1117 VM_OBJECT_ASSERT_WLOCKED(object); 1118 KASSERT(m->object == NULL, 1119 ("vm_page_insert_after: page already inserted")); 1120 if (mpred != NULL) { 1121 KASSERT(mpred->object == object, 1122 ("vm_page_insert_after: object doesn't contain mpred")); 1123 KASSERT(mpred->pindex < pindex, 1124 ("vm_page_insert_after: mpred doesn't precede pindex")); 1125 msucc = TAILQ_NEXT(mpred, listq); 1126 } else 1127 msucc = TAILQ_FIRST(&object->memq); 1128 if (msucc != NULL) 1129 KASSERT(msucc->pindex > pindex, 1130 ("vm_page_insert_after: msucc doesn't succeed pindex")); 1131 1132 /* 1133 * Record the object/offset pair in this page 1134 */ 1135 m->object = object; 1136 m->pindex = pindex; 1137 1138 /* 1139 * Now link into the object's ordered list of backed pages. 1140 */ 1141 if (vm_radix_insert(&object->rtree, m)) { 1142 m->object = NULL; 1143 m->pindex = 0; 1144 return (1); 1145 } 1146 vm_page_insert_radixdone(m, object, mpred); 1147 return (0); 1148 } 1149 1150 /* 1151 * vm_page_insert_radixdone: 1152 * 1153 * Complete page "m" insertion into the specified object after the 1154 * radix trie hooking. 1155 * 1156 * The page "mpred" must precede the offset "m->pindex" within the 1157 * specified object. 1158 * 1159 * The object must be locked. 1160 */ 1161 static void 1162 vm_page_insert_radixdone(vm_page_t m, vm_object_t object, vm_page_t mpred) 1163 { 1164 1165 VM_OBJECT_ASSERT_WLOCKED(object); 1166 KASSERT(object != NULL && m->object == object, 1167 ("vm_page_insert_radixdone: page %p has inconsistent object", m)); 1168 if (mpred != NULL) { 1169 KASSERT(mpred->object == object, 1170 ("vm_page_insert_after: object doesn't contain mpred")); 1171 KASSERT(mpred->pindex < m->pindex, 1172 ("vm_page_insert_after: mpred doesn't precede pindex")); 1173 } 1174 1175 if (mpred != NULL) 1176 TAILQ_INSERT_AFTER(&object->memq, mpred, m, listq); 1177 else 1178 TAILQ_INSERT_HEAD(&object->memq, m, listq); 1179 1180 /* 1181 * Show that the object has one more resident page. 1182 */ 1183 object->resident_page_count++; 1184 1185 /* 1186 * Hold the vnode until the last page is released. 1187 */ 1188 if (object->resident_page_count == 1 && object->type == OBJT_VNODE) 1189 vhold(object->handle); 1190 1191 /* 1192 * Since we are inserting a new and possibly dirty page, 1193 * update the object's OBJ_MIGHTBEDIRTY flag. 1194 */ 1195 if (pmap_page_is_write_mapped(m)) 1196 vm_object_set_writeable_dirty(object); 1197 } 1198 1199 /* 1200 * vm_page_remove: 1201 * 1202 * Removes the given mem entry from the object/offset-page 1203 * table and the object page list, but do not invalidate/terminate 1204 * the backing store. 1205 * 1206 * The object must be locked. The page must be locked if it is managed. 1207 */ 1208 void 1209 vm_page_remove(vm_page_t m) 1210 { 1211 vm_object_t object; 1212 1213 if ((m->oflags & VPO_UNMANAGED) == 0) 1214 vm_page_assert_locked(m); 1215 if ((object = m->object) == NULL) 1216 return; 1217 VM_OBJECT_ASSERT_WLOCKED(object); 1218 if (vm_page_xbusied(m)) 1219 vm_page_xunbusy_maybelocked(m); 1220 1221 /* 1222 * Now remove from the object's list of backed pages. 1223 */ 1224 vm_radix_remove(&object->rtree, m->pindex); 1225 TAILQ_REMOVE(&object->memq, m, listq); 1226 1227 /* 1228 * And show that the object has one fewer resident page. 1229 */ 1230 object->resident_page_count--; 1231 1232 /* 1233 * The vnode may now be recycled. 1234 */ 1235 if (object->resident_page_count == 0 && object->type == OBJT_VNODE) 1236 vdrop(object->handle); 1237 1238 m->object = NULL; 1239 } 1240 1241 /* 1242 * vm_page_lookup: 1243 * 1244 * Returns the page associated with the object/offset 1245 * pair specified; if none is found, NULL is returned. 1246 * 1247 * The object must be locked. 1248 */ 1249 vm_page_t 1250 vm_page_lookup(vm_object_t object, vm_pindex_t pindex) 1251 { 1252 1253 VM_OBJECT_ASSERT_LOCKED(object); 1254 return (vm_radix_lookup(&object->rtree, pindex)); 1255 } 1256 1257 /* 1258 * vm_page_find_least: 1259 * 1260 * Returns the page associated with the object with least pindex 1261 * greater than or equal to the parameter pindex, or NULL. 1262 * 1263 * The object must be locked. 1264 */ 1265 vm_page_t 1266 vm_page_find_least(vm_object_t object, vm_pindex_t pindex) 1267 { 1268 vm_page_t m; 1269 1270 VM_OBJECT_ASSERT_LOCKED(object); 1271 if ((m = TAILQ_FIRST(&object->memq)) != NULL && m->pindex < pindex) 1272 m = vm_radix_lookup_ge(&object->rtree, pindex); 1273 return (m); 1274 } 1275 1276 /* 1277 * Returns the given page's successor (by pindex) within the object if it is 1278 * resident; if none is found, NULL is returned. 1279 * 1280 * The object must be locked. 1281 */ 1282 vm_page_t 1283 vm_page_next(vm_page_t m) 1284 { 1285 vm_page_t next; 1286 1287 VM_OBJECT_ASSERT_LOCKED(m->object); 1288 if ((next = TAILQ_NEXT(m, listq)) != NULL && 1289 next->pindex != m->pindex + 1) 1290 next = NULL; 1291 return (next); 1292 } 1293 1294 /* 1295 * Returns the given page's predecessor (by pindex) within the object if it is 1296 * resident; if none is found, NULL is returned. 1297 * 1298 * The object must be locked. 1299 */ 1300 vm_page_t 1301 vm_page_prev(vm_page_t m) 1302 { 1303 vm_page_t prev; 1304 1305 VM_OBJECT_ASSERT_LOCKED(m->object); 1306 if ((prev = TAILQ_PREV(m, pglist, listq)) != NULL && 1307 prev->pindex != m->pindex - 1) 1308 prev = NULL; 1309 return (prev); 1310 } 1311 1312 /* 1313 * Uses the page mnew as a replacement for an existing page at index 1314 * pindex which must be already present in the object. 1315 * 1316 * The existing page must not be on a paging queue. 1317 */ 1318 vm_page_t 1319 vm_page_replace(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex) 1320 { 1321 vm_page_t mold; 1322 1323 VM_OBJECT_ASSERT_WLOCKED(object); 1324 KASSERT(mnew->object == NULL, 1325 ("vm_page_replace: page already in object")); 1326 1327 /* 1328 * This function mostly follows vm_page_insert() and 1329 * vm_page_remove() without the radix, object count and vnode 1330 * dance. Double check such functions for more comments. 1331 */ 1332 1333 mnew->object = object; 1334 mnew->pindex = pindex; 1335 mold = vm_radix_replace(&object->rtree, mnew); 1336 KASSERT(mold->queue == PQ_NONE, 1337 ("vm_page_replace: mold is on a paging queue")); 1338 1339 /* Keep the resident page list in sorted order. */ 1340 TAILQ_INSERT_AFTER(&object->memq, mold, mnew, listq); 1341 TAILQ_REMOVE(&object->memq, mold, listq); 1342 1343 mold->object = NULL; 1344 vm_page_xunbusy_maybelocked(mold); 1345 1346 /* 1347 * The object's resident_page_count does not change because we have 1348 * swapped one page for another, but OBJ_MIGHTBEDIRTY. 1349 */ 1350 if (pmap_page_is_write_mapped(mnew)) 1351 vm_object_set_writeable_dirty(object); 1352 return (mold); 1353 } 1354 1355 /* 1356 * vm_page_rename: 1357 * 1358 * Move the given memory entry from its 1359 * current object to the specified target object/offset. 1360 * 1361 * Note: swap associated with the page must be invalidated by the move. We 1362 * have to do this for several reasons: (1) we aren't freeing the 1363 * page, (2) we are dirtying the page, (3) the VM system is probably 1364 * moving the page from object A to B, and will then later move 1365 * the backing store from A to B and we can't have a conflict. 1366 * 1367 * Note: we *always* dirty the page. It is necessary both for the 1368 * fact that we moved it, and because we may be invalidating 1369 * swap. If the page is on the cache, we have to deactivate it 1370 * or vm_page_dirty() will panic. Dirty pages are not allowed 1371 * on the cache. 1372 * 1373 * The objects must be locked. 1374 */ 1375 int 1376 vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex) 1377 { 1378 vm_page_t mpred; 1379 vm_pindex_t opidx; 1380 1381 VM_OBJECT_ASSERT_WLOCKED(new_object); 1382 1383 mpred = vm_radix_lookup_le(&new_object->rtree, new_pindex); 1384 KASSERT(mpred == NULL || mpred->pindex != new_pindex, 1385 ("vm_page_rename: pindex already renamed")); 1386 1387 /* 1388 * Create a custom version of vm_page_insert() which does not depend 1389 * by m_prev and can cheat on the implementation aspects of the 1390 * function. 1391 */ 1392 opidx = m->pindex; 1393 m->pindex = new_pindex; 1394 if (vm_radix_insert(&new_object->rtree, m)) { 1395 m->pindex = opidx; 1396 return (1); 1397 } 1398 1399 /* 1400 * The operation cannot fail anymore. The removal must happen before 1401 * the listq iterator is tainted. 1402 */ 1403 m->pindex = opidx; 1404 vm_page_lock(m); 1405 vm_page_remove(m); 1406 1407 /* Return back to the new pindex to complete vm_page_insert(). */ 1408 m->pindex = new_pindex; 1409 m->object = new_object; 1410 vm_page_unlock(m); 1411 vm_page_insert_radixdone(m, new_object, mpred); 1412 vm_page_dirty(m); 1413 return (0); 1414 } 1415 1416 /* 1417 * Convert all of the given object's cached pages that have a 1418 * pindex within the given range into free pages. If the value 1419 * zero is given for "end", then the range's upper bound is 1420 * infinity. If the given object is backed by a vnode and it 1421 * transitions from having one or more cached pages to none, the 1422 * vnode's hold count is reduced. 1423 */ 1424 void 1425 vm_page_cache_free(vm_object_t object, vm_pindex_t start, vm_pindex_t end) 1426 { 1427 vm_page_t m; 1428 boolean_t empty; 1429 1430 mtx_lock(&vm_page_queue_free_mtx); 1431 if (__predict_false(vm_radix_is_empty(&object->cache))) { 1432 mtx_unlock(&vm_page_queue_free_mtx); 1433 return; 1434 } 1435 while ((m = vm_radix_lookup_ge(&object->cache, start)) != NULL) { 1436 if (end != 0 && m->pindex >= end) 1437 break; 1438 vm_radix_remove(&object->cache, m->pindex); 1439 vm_page_cache_turn_free(m); 1440 } 1441 empty = vm_radix_is_empty(&object->cache); 1442 mtx_unlock(&vm_page_queue_free_mtx); 1443 if (object->type == OBJT_VNODE && empty) 1444 vdrop(object->handle); 1445 } 1446 1447 /* 1448 * Returns the cached page that is associated with the given 1449 * object and offset. If, however, none exists, returns NULL. 1450 * 1451 * The free page queue must be locked. 1452 */ 1453 static inline vm_page_t 1454 vm_page_cache_lookup(vm_object_t object, vm_pindex_t pindex) 1455 { 1456 1457 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 1458 return (vm_radix_lookup(&object->cache, pindex)); 1459 } 1460 1461 /* 1462 * Remove the given cached page from its containing object's 1463 * collection of cached pages. 1464 * 1465 * The free page queue must be locked. 1466 */ 1467 static void 1468 vm_page_cache_remove(vm_page_t m) 1469 { 1470 1471 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 1472 KASSERT((m->flags & PG_CACHED) != 0, 1473 ("vm_page_cache_remove: page %p is not cached", m)); 1474 vm_radix_remove(&m->object->cache, m->pindex); 1475 m->object = NULL; 1476 vm_cnt.v_cache_count--; 1477 } 1478 1479 /* 1480 * Transfer all of the cached pages with offset greater than or 1481 * equal to 'offidxstart' from the original object's cache to the 1482 * new object's cache. However, any cached pages with offset 1483 * greater than or equal to the new object's size are kept in the 1484 * original object. Initially, the new object's cache must be 1485 * empty. Offset 'offidxstart' in the original object must 1486 * correspond to offset zero in the new object. 1487 * 1488 * The new object must be locked. 1489 */ 1490 void 1491 vm_page_cache_transfer(vm_object_t orig_object, vm_pindex_t offidxstart, 1492 vm_object_t new_object) 1493 { 1494 vm_page_t m; 1495 1496 /* 1497 * Insertion into an object's collection of cached pages 1498 * requires the object to be locked. In contrast, removal does 1499 * not. 1500 */ 1501 VM_OBJECT_ASSERT_WLOCKED(new_object); 1502 KASSERT(vm_radix_is_empty(&new_object->cache), 1503 ("vm_page_cache_transfer: object %p has cached pages", 1504 new_object)); 1505 mtx_lock(&vm_page_queue_free_mtx); 1506 while ((m = vm_radix_lookup_ge(&orig_object->cache, 1507 offidxstart)) != NULL) { 1508 /* 1509 * Transfer all of the pages with offset greater than or 1510 * equal to 'offidxstart' from the original object's 1511 * cache to the new object's cache. 1512 */ 1513 if ((m->pindex - offidxstart) >= new_object->size) 1514 break; 1515 vm_radix_remove(&orig_object->cache, m->pindex); 1516 /* Update the page's object and offset. */ 1517 m->object = new_object; 1518 m->pindex -= offidxstart; 1519 if (vm_radix_insert(&new_object->cache, m)) 1520 vm_page_cache_turn_free(m); 1521 } 1522 mtx_unlock(&vm_page_queue_free_mtx); 1523 } 1524 1525 /* 1526 * Returns TRUE if a cached page is associated with the given object and 1527 * offset, and FALSE otherwise. 1528 * 1529 * The object must be locked. 1530 */ 1531 boolean_t 1532 vm_page_is_cached(vm_object_t object, vm_pindex_t pindex) 1533 { 1534 vm_page_t m; 1535 1536 /* 1537 * Insertion into an object's collection of cached pages requires the 1538 * object to be locked. Therefore, if the object is locked and the 1539 * object's collection is empty, there is no need to acquire the free 1540 * page queues lock in order to prove that the specified page doesn't 1541 * exist. 1542 */ 1543 VM_OBJECT_ASSERT_WLOCKED(object); 1544 if (__predict_true(vm_object_cache_is_empty(object))) 1545 return (FALSE); 1546 mtx_lock(&vm_page_queue_free_mtx); 1547 m = vm_page_cache_lookup(object, pindex); 1548 mtx_unlock(&vm_page_queue_free_mtx); 1549 return (m != NULL); 1550 } 1551 1552 /* 1553 * vm_page_alloc: 1554 * 1555 * Allocate and return a page that is associated with the specified 1556 * object and offset pair. By default, this page is exclusive busied. 1557 * 1558 * The caller must always specify an allocation class. 1559 * 1560 * allocation classes: 1561 * VM_ALLOC_NORMAL normal process request 1562 * VM_ALLOC_SYSTEM system *really* needs a page 1563 * VM_ALLOC_INTERRUPT interrupt time request 1564 * 1565 * optional allocation flags: 1566 * VM_ALLOC_COUNT(number) the number of additional pages that the caller 1567 * intends to allocate 1568 * VM_ALLOC_IFCACHED return page only if it is cached 1569 * VM_ALLOC_IFNOTCACHED return NULL, do not reactivate if the page 1570 * is cached 1571 * VM_ALLOC_NOBUSY do not exclusive busy the page 1572 * VM_ALLOC_NODUMP do not include the page in a kernel core dump 1573 * VM_ALLOC_NOOBJ page is not associated with an object and 1574 * should not be exclusive busy 1575 * VM_ALLOC_SBUSY shared busy the allocated page 1576 * VM_ALLOC_WIRED wire the allocated page 1577 * VM_ALLOC_ZERO prefer a zeroed page 1578 * 1579 * This routine may not sleep. 1580 */ 1581 vm_page_t 1582 vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req) 1583 { 1584 struct vnode *vp = NULL; 1585 vm_object_t m_object; 1586 vm_page_t m, mpred; 1587 int flags, req_class; 1588 1589 mpred = 0; /* XXX: pacify gcc */ 1590 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) && 1591 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) && 1592 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 1593 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 1594 ("vm_page_alloc: inconsistent object(%p)/req(%x)", (void *)object, 1595 req)); 1596 if (object != NULL) 1597 VM_OBJECT_ASSERT_WLOCKED(object); 1598 1599 req_class = req & VM_ALLOC_CLASS_MASK; 1600 1601 /* 1602 * The page daemon is allowed to dig deeper into the free page list. 1603 */ 1604 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 1605 req_class = VM_ALLOC_SYSTEM; 1606 1607 if (object != NULL) { 1608 mpred = vm_radix_lookup_le(&object->rtree, pindex); 1609 KASSERT(mpred == NULL || mpred->pindex != pindex, 1610 ("vm_page_alloc: pindex already allocated")); 1611 } 1612 1613 /* 1614 * The page allocation request can came from consumers which already 1615 * hold the free page queue mutex, like vm_page_insert() in 1616 * vm_page_cache(). 1617 */ 1618 mtx_lock_flags(&vm_page_queue_free_mtx, MTX_RECURSE); 1619 if (vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_free_reserved || 1620 (req_class == VM_ALLOC_SYSTEM && 1621 vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_interrupt_free_min) || 1622 (req_class == VM_ALLOC_INTERRUPT && 1623 vm_cnt.v_free_count + vm_cnt.v_cache_count > 0)) { 1624 /* 1625 * Allocate from the free queue if the number of free pages 1626 * exceeds the minimum for the request class. 1627 */ 1628 if (object != NULL && 1629 (m = vm_page_cache_lookup(object, pindex)) != NULL) { 1630 if ((req & VM_ALLOC_IFNOTCACHED) != 0) { 1631 mtx_unlock(&vm_page_queue_free_mtx); 1632 return (NULL); 1633 } 1634 if (vm_phys_unfree_page(m)) 1635 vm_phys_set_pool(VM_FREEPOOL_DEFAULT, m, 0); 1636 #if VM_NRESERVLEVEL > 0 1637 else if (!vm_reserv_reactivate_page(m)) 1638 #else 1639 else 1640 #endif 1641 panic("vm_page_alloc: cache page %p is missing" 1642 " from the free queue", m); 1643 } else if ((req & VM_ALLOC_IFCACHED) != 0) { 1644 mtx_unlock(&vm_page_queue_free_mtx); 1645 return (NULL); 1646 #if VM_NRESERVLEVEL > 0 1647 } else if (object == NULL || (object->flags & (OBJ_COLORED | 1648 OBJ_FICTITIOUS)) != OBJ_COLORED || (m = 1649 vm_reserv_alloc_page(object, pindex, mpred)) == NULL) { 1650 #else 1651 } else { 1652 #endif 1653 m = vm_phys_alloc_pages(object != NULL ? 1654 VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT, 0); 1655 #if VM_NRESERVLEVEL > 0 1656 if (m == NULL && vm_reserv_reclaim_inactive()) { 1657 m = vm_phys_alloc_pages(object != NULL ? 1658 VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT, 1659 0); 1660 } 1661 #endif 1662 } 1663 } else { 1664 /* 1665 * Not allocatable, give up. 1666 */ 1667 mtx_unlock(&vm_page_queue_free_mtx); 1668 atomic_add_int(&vm_pageout_deficit, 1669 max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1)); 1670 pagedaemon_wakeup(); 1671 return (NULL); 1672 } 1673 1674 /* 1675 * At this point we had better have found a good page. 1676 */ 1677 KASSERT(m != NULL, ("vm_page_alloc: missing page")); 1678 KASSERT(m->queue == PQ_NONE, 1679 ("vm_page_alloc: page %p has unexpected queue %d", m, m->queue)); 1680 KASSERT(m->wire_count == 0, ("vm_page_alloc: page %p is wired", m)); 1681 KASSERT(m->hold_count == 0, ("vm_page_alloc: page %p is held", m)); 1682 KASSERT(!vm_page_sbusied(m), 1683 ("vm_page_alloc: page %p is busy", m)); 1684 KASSERT(m->dirty == 0, ("vm_page_alloc: page %p is dirty", m)); 1685 KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, 1686 ("vm_page_alloc: page %p has unexpected memattr %d", m, 1687 pmap_page_get_memattr(m))); 1688 if ((m->flags & PG_CACHED) != 0) { 1689 KASSERT((m->flags & PG_ZERO) == 0, 1690 ("vm_page_alloc: cached page %p is PG_ZERO", m)); 1691 KASSERT(m->valid != 0, 1692 ("vm_page_alloc: cached page %p is invalid", m)); 1693 if (m->object == object && m->pindex == pindex) 1694 vm_cnt.v_reactivated++; 1695 else 1696 m->valid = 0; 1697 m_object = m->object; 1698 vm_page_cache_remove(m); 1699 if (m_object->type == OBJT_VNODE && 1700 vm_object_cache_is_empty(m_object)) 1701 vp = m_object->handle; 1702 } else { 1703 KASSERT(m->valid == 0, 1704 ("vm_page_alloc: free page %p is valid", m)); 1705 vm_phys_freecnt_adj(m, -1); 1706 if ((m->flags & PG_ZERO) != 0) 1707 vm_page_zero_count--; 1708 } 1709 mtx_unlock(&vm_page_queue_free_mtx); 1710 1711 /* 1712 * Initialize the page. Only the PG_ZERO flag is inherited. 1713 */ 1714 flags = 0; 1715 if ((req & VM_ALLOC_ZERO) != 0) 1716 flags = PG_ZERO; 1717 flags &= m->flags; 1718 if ((req & VM_ALLOC_NODUMP) != 0) 1719 flags |= PG_NODUMP; 1720 m->flags = flags; 1721 m->aflags = 0; 1722 m->oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ? 1723 VPO_UNMANAGED : 0; 1724 m->busy_lock = VPB_UNBUSIED; 1725 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0) 1726 m->busy_lock = VPB_SINGLE_EXCLUSIVER; 1727 if ((req & VM_ALLOC_SBUSY) != 0) 1728 m->busy_lock = VPB_SHARERS_WORD(1); 1729 if (req & VM_ALLOC_WIRED) { 1730 /* 1731 * The page lock is not required for wiring a page until that 1732 * page is inserted into the object. 1733 */ 1734 atomic_add_int(&vm_cnt.v_wire_count, 1); 1735 m->wire_count = 1; 1736 } 1737 m->act_count = 0; 1738 1739 if (object != NULL) { 1740 if (vm_page_insert_after(m, object, pindex, mpred)) { 1741 /* See the comment below about hold count. */ 1742 if (vp != NULL) 1743 vdrop(vp); 1744 pagedaemon_wakeup(); 1745 if (req & VM_ALLOC_WIRED) { 1746 atomic_subtract_int(&vm_cnt.v_wire_count, 1); 1747 m->wire_count = 0; 1748 } 1749 m->object = NULL; 1750 m->oflags = VPO_UNMANAGED; 1751 m->busy_lock = VPB_UNBUSIED; 1752 vm_page_free(m); 1753 return (NULL); 1754 } 1755 1756 /* Ignore device objects; the pager sets "memattr" for them. */ 1757 if (object->memattr != VM_MEMATTR_DEFAULT && 1758 (object->flags & OBJ_FICTITIOUS) == 0) 1759 pmap_page_set_memattr(m, object->memattr); 1760 } else 1761 m->pindex = pindex; 1762 1763 /* 1764 * The following call to vdrop() must come after the above call 1765 * to vm_page_insert() in case both affect the same object and 1766 * vnode. Otherwise, the affected vnode's hold count could 1767 * temporarily become zero. 1768 */ 1769 if (vp != NULL) 1770 vdrop(vp); 1771 1772 /* 1773 * Don't wakeup too often - wakeup the pageout daemon when 1774 * we would be nearly out of memory. 1775 */ 1776 if (vm_paging_needed()) 1777 pagedaemon_wakeup(); 1778 1779 return (m); 1780 } 1781 1782 static void 1783 vm_page_alloc_contig_vdrop(struct spglist *lst) 1784 { 1785 1786 while (!SLIST_EMPTY(lst)) { 1787 vdrop((struct vnode *)SLIST_FIRST(lst)-> plinks.s.pv); 1788 SLIST_REMOVE_HEAD(lst, plinks.s.ss); 1789 } 1790 } 1791 1792 /* 1793 * vm_page_alloc_contig: 1794 * 1795 * Allocate a contiguous set of physical pages of the given size "npages" 1796 * from the free lists. All of the physical pages must be at or above 1797 * the given physical address "low" and below the given physical address 1798 * "high". The given value "alignment" determines the alignment of the 1799 * first physical page in the set. If the given value "boundary" is 1800 * non-zero, then the set of physical pages cannot cross any physical 1801 * address boundary that is a multiple of that value. Both "alignment" 1802 * and "boundary" must be a power of two. 1803 * 1804 * If the specified memory attribute, "memattr", is VM_MEMATTR_DEFAULT, 1805 * then the memory attribute setting for the physical pages is configured 1806 * to the object's memory attribute setting. Otherwise, the memory 1807 * attribute setting for the physical pages is configured to "memattr", 1808 * overriding the object's memory attribute setting. However, if the 1809 * object's memory attribute setting is not VM_MEMATTR_DEFAULT, then the 1810 * memory attribute setting for the physical pages cannot be configured 1811 * to VM_MEMATTR_DEFAULT. 1812 * 1813 * The caller must always specify an allocation class. 1814 * 1815 * allocation classes: 1816 * VM_ALLOC_NORMAL normal process request 1817 * VM_ALLOC_SYSTEM system *really* needs a page 1818 * VM_ALLOC_INTERRUPT interrupt time request 1819 * 1820 * optional allocation flags: 1821 * VM_ALLOC_NOBUSY do not exclusive busy the page 1822 * VM_ALLOC_NODUMP do not include the page in a kernel core dump 1823 * VM_ALLOC_NOOBJ page is not associated with an object and 1824 * should not be exclusive busy 1825 * VM_ALLOC_SBUSY shared busy the allocated page 1826 * VM_ALLOC_WIRED wire the allocated page 1827 * VM_ALLOC_ZERO prefer a zeroed page 1828 * 1829 * This routine may not sleep. 1830 */ 1831 vm_page_t 1832 vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req, 1833 u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, 1834 vm_paddr_t boundary, vm_memattr_t memattr) 1835 { 1836 struct vnode *drop; 1837 struct spglist deferred_vdrop_list; 1838 vm_page_t m, m_tmp, m_ret; 1839 u_int flags; 1840 int req_class; 1841 1842 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) && 1843 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) && 1844 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 1845 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 1846 ("vm_page_alloc: inconsistent object(%p)/req(%x)", (void *)object, 1847 req)); 1848 if (object != NULL) { 1849 VM_OBJECT_ASSERT_WLOCKED(object); 1850 KASSERT(object->type == OBJT_PHYS, 1851 ("vm_page_alloc_contig: object %p isn't OBJT_PHYS", 1852 object)); 1853 } 1854 KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero")); 1855 req_class = req & VM_ALLOC_CLASS_MASK; 1856 1857 /* 1858 * The page daemon is allowed to dig deeper into the free page list. 1859 */ 1860 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 1861 req_class = VM_ALLOC_SYSTEM; 1862 1863 SLIST_INIT(&deferred_vdrop_list); 1864 mtx_lock(&vm_page_queue_free_mtx); 1865 if (vm_cnt.v_free_count + vm_cnt.v_cache_count >= npages + 1866 vm_cnt.v_free_reserved || (req_class == VM_ALLOC_SYSTEM && 1867 vm_cnt.v_free_count + vm_cnt.v_cache_count >= npages + 1868 vm_cnt.v_interrupt_free_min) || (req_class == VM_ALLOC_INTERRUPT && 1869 vm_cnt.v_free_count + vm_cnt.v_cache_count >= npages)) { 1870 #if VM_NRESERVLEVEL > 0 1871 retry: 1872 if (object == NULL || (object->flags & OBJ_COLORED) == 0 || 1873 (m_ret = vm_reserv_alloc_contig(object, pindex, npages, 1874 low, high, alignment, boundary)) == NULL) 1875 #endif 1876 m_ret = vm_phys_alloc_contig(npages, low, high, 1877 alignment, boundary); 1878 } else { 1879 mtx_unlock(&vm_page_queue_free_mtx); 1880 atomic_add_int(&vm_pageout_deficit, npages); 1881 pagedaemon_wakeup(); 1882 return (NULL); 1883 } 1884 if (m_ret != NULL) 1885 for (m = m_ret; m < &m_ret[npages]; m++) { 1886 drop = vm_page_alloc_init(m); 1887 if (drop != NULL) { 1888 /* 1889 * Enqueue the vnode for deferred vdrop(). 1890 */ 1891 m->plinks.s.pv = drop; 1892 SLIST_INSERT_HEAD(&deferred_vdrop_list, m, 1893 plinks.s.ss); 1894 } 1895 } 1896 else { 1897 #if VM_NRESERVLEVEL > 0 1898 if (vm_reserv_reclaim_contig(npages, low, high, alignment, 1899 boundary)) 1900 goto retry; 1901 #endif 1902 } 1903 mtx_unlock(&vm_page_queue_free_mtx); 1904 if (m_ret == NULL) 1905 return (NULL); 1906 1907 /* 1908 * Initialize the pages. Only the PG_ZERO flag is inherited. 1909 */ 1910 flags = 0; 1911 if ((req & VM_ALLOC_ZERO) != 0) 1912 flags = PG_ZERO; 1913 if ((req & VM_ALLOC_NODUMP) != 0) 1914 flags |= PG_NODUMP; 1915 if ((req & VM_ALLOC_WIRED) != 0) 1916 atomic_add_int(&vm_cnt.v_wire_count, npages); 1917 if (object != NULL) { 1918 if (object->memattr != VM_MEMATTR_DEFAULT && 1919 memattr == VM_MEMATTR_DEFAULT) 1920 memattr = object->memattr; 1921 } 1922 for (m = m_ret; m < &m_ret[npages]; m++) { 1923 m->aflags = 0; 1924 m->flags = (m->flags | PG_NODUMP) & flags; 1925 m->busy_lock = VPB_UNBUSIED; 1926 if (object != NULL) { 1927 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0) 1928 m->busy_lock = VPB_SINGLE_EXCLUSIVER; 1929 if ((req & VM_ALLOC_SBUSY) != 0) 1930 m->busy_lock = VPB_SHARERS_WORD(1); 1931 } 1932 if ((req & VM_ALLOC_WIRED) != 0) 1933 m->wire_count = 1; 1934 /* Unmanaged pages don't use "act_count". */ 1935 m->oflags = VPO_UNMANAGED; 1936 if (object != NULL) { 1937 if (vm_page_insert(m, object, pindex)) { 1938 vm_page_alloc_contig_vdrop( 1939 &deferred_vdrop_list); 1940 if (vm_paging_needed()) 1941 pagedaemon_wakeup(); 1942 if ((req & VM_ALLOC_WIRED) != 0) 1943 atomic_subtract_int(&vm_cnt.v_wire_count, 1944 npages); 1945 for (m_tmp = m, m = m_ret; 1946 m < &m_ret[npages]; m++) { 1947 if ((req & VM_ALLOC_WIRED) != 0) 1948 m->wire_count = 0; 1949 if (m >= m_tmp) { 1950 m->object = NULL; 1951 m->oflags |= VPO_UNMANAGED; 1952 } 1953 m->busy_lock = VPB_UNBUSIED; 1954 vm_page_free(m); 1955 } 1956 return (NULL); 1957 } 1958 } else 1959 m->pindex = pindex; 1960 if (memattr != VM_MEMATTR_DEFAULT) 1961 pmap_page_set_memattr(m, memattr); 1962 pindex++; 1963 } 1964 vm_page_alloc_contig_vdrop(&deferred_vdrop_list); 1965 if (vm_paging_needed()) 1966 pagedaemon_wakeup(); 1967 return (m_ret); 1968 } 1969 1970 /* 1971 * Initialize a page that has been freshly dequeued from a freelist. 1972 * The caller has to drop the vnode returned, if it is not NULL. 1973 * 1974 * This function may only be used to initialize unmanaged pages. 1975 * 1976 * To be called with vm_page_queue_free_mtx held. 1977 */ 1978 static struct vnode * 1979 vm_page_alloc_init(vm_page_t m) 1980 { 1981 struct vnode *drop; 1982 vm_object_t m_object; 1983 1984 KASSERT(m->queue == PQ_NONE, 1985 ("vm_page_alloc_init: page %p has unexpected queue %d", 1986 m, m->queue)); 1987 KASSERT(m->wire_count == 0, 1988 ("vm_page_alloc_init: page %p is wired", m)); 1989 KASSERT(m->hold_count == 0, 1990 ("vm_page_alloc_init: page %p is held", m)); 1991 KASSERT(!vm_page_sbusied(m), 1992 ("vm_page_alloc_init: page %p is busy", m)); 1993 KASSERT(m->dirty == 0, 1994 ("vm_page_alloc_init: page %p is dirty", m)); 1995 KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, 1996 ("vm_page_alloc_init: page %p has unexpected memattr %d", 1997 m, pmap_page_get_memattr(m))); 1998 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 1999 drop = NULL; 2000 if ((m->flags & PG_CACHED) != 0) { 2001 KASSERT((m->flags & PG_ZERO) == 0, 2002 ("vm_page_alloc_init: cached page %p is PG_ZERO", m)); 2003 m->valid = 0; 2004 m_object = m->object; 2005 vm_page_cache_remove(m); 2006 if (m_object->type == OBJT_VNODE && 2007 vm_object_cache_is_empty(m_object)) 2008 drop = m_object->handle; 2009 } else { 2010 KASSERT(m->valid == 0, 2011 ("vm_page_alloc_init: free page %p is valid", m)); 2012 vm_phys_freecnt_adj(m, -1); 2013 if ((m->flags & PG_ZERO) != 0) 2014 vm_page_zero_count--; 2015 } 2016 return (drop); 2017 } 2018 2019 /* 2020 * vm_page_alloc_freelist: 2021 * 2022 * Allocate a physical page from the specified free page list. 2023 * 2024 * The caller must always specify an allocation class. 2025 * 2026 * allocation classes: 2027 * VM_ALLOC_NORMAL normal process request 2028 * VM_ALLOC_SYSTEM system *really* needs a page 2029 * VM_ALLOC_INTERRUPT interrupt time request 2030 * 2031 * optional allocation flags: 2032 * VM_ALLOC_COUNT(number) the number of additional pages that the caller 2033 * intends to allocate 2034 * VM_ALLOC_WIRED wire the allocated page 2035 * VM_ALLOC_ZERO prefer a zeroed page 2036 * 2037 * This routine may not sleep. 2038 */ 2039 vm_page_t 2040 vm_page_alloc_freelist(int flind, int req) 2041 { 2042 struct vnode *drop; 2043 vm_page_t m; 2044 u_int flags; 2045 int req_class; 2046 2047 req_class = req & VM_ALLOC_CLASS_MASK; 2048 2049 /* 2050 * The page daemon is allowed to dig deeper into the free page list. 2051 */ 2052 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 2053 req_class = VM_ALLOC_SYSTEM; 2054 2055 /* 2056 * Do not allocate reserved pages unless the req has asked for it. 2057 */ 2058 mtx_lock_flags(&vm_page_queue_free_mtx, MTX_RECURSE); 2059 if (vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_free_reserved || 2060 (req_class == VM_ALLOC_SYSTEM && 2061 vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_interrupt_free_min) || 2062 (req_class == VM_ALLOC_INTERRUPT && 2063 vm_cnt.v_free_count + vm_cnt.v_cache_count > 0)) 2064 m = vm_phys_alloc_freelist_pages(flind, VM_FREEPOOL_DIRECT, 0); 2065 else { 2066 mtx_unlock(&vm_page_queue_free_mtx); 2067 atomic_add_int(&vm_pageout_deficit, 2068 max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1)); 2069 pagedaemon_wakeup(); 2070 return (NULL); 2071 } 2072 if (m == NULL) { 2073 mtx_unlock(&vm_page_queue_free_mtx); 2074 return (NULL); 2075 } 2076 drop = vm_page_alloc_init(m); 2077 mtx_unlock(&vm_page_queue_free_mtx); 2078 2079 /* 2080 * Initialize the page. Only the PG_ZERO flag is inherited. 2081 */ 2082 m->aflags = 0; 2083 flags = 0; 2084 if ((req & VM_ALLOC_ZERO) != 0) 2085 flags = PG_ZERO; 2086 m->flags &= flags; 2087 if ((req & VM_ALLOC_WIRED) != 0) { 2088 /* 2089 * The page lock is not required for wiring a page that does 2090 * not belong to an object. 2091 */ 2092 atomic_add_int(&vm_cnt.v_wire_count, 1); 2093 m->wire_count = 1; 2094 } 2095 /* Unmanaged pages don't use "act_count". */ 2096 m->oflags = VPO_UNMANAGED; 2097 if (drop != NULL) 2098 vdrop(drop); 2099 if (vm_paging_needed()) 2100 pagedaemon_wakeup(); 2101 return (m); 2102 } 2103 2104 #define VPSC_ANY 0 /* No restrictions. */ 2105 #define VPSC_NORESERV 1 /* Skip reservations; implies VPSC_NOSUPER. */ 2106 #define VPSC_NOSUPER 2 /* Skip superpages. */ 2107 2108 /* 2109 * vm_page_scan_contig: 2110 * 2111 * Scan vm_page_array[] between the specified entries "m_start" and 2112 * "m_end" for a run of contiguous physical pages that satisfy the 2113 * specified conditions, and return the lowest page in the run. The 2114 * specified "alignment" determines the alignment of the lowest physical 2115 * page in the run. If the specified "boundary" is non-zero, then the 2116 * run of physical pages cannot span a physical address that is a 2117 * multiple of "boundary". 2118 * 2119 * "m_end" is never dereferenced, so it need not point to a vm_page 2120 * structure within vm_page_array[]. 2121 * 2122 * "npages" must be greater than zero. "m_start" and "m_end" must not 2123 * span a hole (or discontiguity) in the physical address space. Both 2124 * "alignment" and "boundary" must be a power of two. 2125 */ 2126 vm_page_t 2127 vm_page_scan_contig(u_long npages, vm_page_t m_start, vm_page_t m_end, 2128 u_long alignment, vm_paddr_t boundary, int options) 2129 { 2130 struct mtx *m_mtx, *new_mtx; 2131 vm_object_t object; 2132 vm_paddr_t pa; 2133 vm_page_t m, m_run; 2134 #if VM_NRESERVLEVEL > 0 2135 int level; 2136 #endif 2137 int m_inc, order, run_ext, run_len; 2138 2139 KASSERT(npages > 0, ("npages is 0")); 2140 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 2141 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 2142 m_run = NULL; 2143 run_len = 0; 2144 m_mtx = NULL; 2145 for (m = m_start; m < m_end && run_len < npages; m += m_inc) { 2146 KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0, 2147 ("page %p is PG_FICTITIOUS or PG_MARKER", m)); 2148 2149 /* 2150 * If the current page would be the start of a run, check its 2151 * physical address against the end, alignment, and boundary 2152 * conditions. If it doesn't satisfy these conditions, either 2153 * terminate the scan or advance to the next page that 2154 * satisfies the failed condition. 2155 */ 2156 if (run_len == 0) { 2157 KASSERT(m_run == NULL, ("m_run != NULL")); 2158 if (m + npages > m_end) 2159 break; 2160 pa = VM_PAGE_TO_PHYS(m); 2161 if ((pa & (alignment - 1)) != 0) { 2162 m_inc = atop(roundup2(pa, alignment) - pa); 2163 continue; 2164 } 2165 if (rounddown2(pa ^ (pa + ptoa(npages) - 1), 2166 boundary) != 0) { 2167 m_inc = atop(roundup2(pa, boundary) - pa); 2168 continue; 2169 } 2170 } else 2171 KASSERT(m_run != NULL, ("m_run == NULL")); 2172 2173 /* 2174 * Avoid releasing and reacquiring the same page lock. 2175 */ 2176 new_mtx = vm_page_lockptr(m); 2177 if (m_mtx != new_mtx) { 2178 if (m_mtx != NULL) 2179 mtx_unlock(m_mtx); 2180 m_mtx = new_mtx; 2181 mtx_lock(m_mtx); 2182 } 2183 m_inc = 1; 2184 retry: 2185 if (m->wire_count != 0 || m->hold_count != 0) 2186 run_ext = 0; 2187 #if VM_NRESERVLEVEL > 0 2188 else if ((level = vm_reserv_level(m)) >= 0 && 2189 (options & VPSC_NORESERV) != 0) { 2190 run_ext = 0; 2191 /* Advance to the end of the reservation. */ 2192 pa = VM_PAGE_TO_PHYS(m); 2193 m_inc = atop(roundup2(pa + 1, vm_reserv_size(level)) - 2194 pa); 2195 } 2196 #endif 2197 else if ((object = m->object) != NULL) { 2198 /* 2199 * The page is considered eligible for relocation if 2200 * and only if it could be laundered or reclaimed by 2201 * the page daemon. 2202 */ 2203 if (!VM_OBJECT_TRYRLOCK(object)) { 2204 mtx_unlock(m_mtx); 2205 VM_OBJECT_RLOCK(object); 2206 mtx_lock(m_mtx); 2207 if (m->object != object) { 2208 /* 2209 * The page may have been freed. 2210 */ 2211 VM_OBJECT_RUNLOCK(object); 2212 goto retry; 2213 } else if (m->wire_count != 0 || 2214 m->hold_count != 0) { 2215 run_ext = 0; 2216 goto unlock; 2217 } 2218 } 2219 KASSERT((m->flags & PG_UNHOLDFREE) == 0, 2220 ("page %p is PG_UNHOLDFREE", m)); 2221 /* Don't care: PG_NODUMP, PG_WINATCFLS, PG_ZERO. */ 2222 if (object->type != OBJT_DEFAULT && 2223 object->type != OBJT_SWAP && 2224 object->type != OBJT_VNODE) 2225 run_ext = 0; 2226 else if ((m->flags & PG_CACHED) != 0 || 2227 m != vm_page_lookup(object, m->pindex)) { 2228 /* 2229 * The page is cached or recently converted 2230 * from cached to free. 2231 */ 2232 #if VM_NRESERVLEVEL > 0 2233 if (level >= 0) { 2234 /* 2235 * The page is reserved. Extend the 2236 * current run by one page. 2237 */ 2238 run_ext = 1; 2239 } else 2240 #endif 2241 if ((order = m->order) < VM_NFREEORDER) { 2242 /* 2243 * The page is enqueued in the 2244 * physical memory allocator's cache/ 2245 * free page queues. Moreover, it is 2246 * the first page in a power-of-two- 2247 * sized run of contiguous cache/free 2248 * pages. Add these pages to the end 2249 * of the current run, and jump 2250 * ahead. 2251 */ 2252 run_ext = 1 << order; 2253 m_inc = 1 << order; 2254 } else 2255 run_ext = 0; 2256 #if VM_NRESERVLEVEL > 0 2257 } else if ((options & VPSC_NOSUPER) != 0 && 2258 (level = vm_reserv_level_iffullpop(m)) >= 0) { 2259 run_ext = 0; 2260 /* Advance to the end of the superpage. */ 2261 pa = VM_PAGE_TO_PHYS(m); 2262 m_inc = atop(roundup2(pa + 1, 2263 vm_reserv_size(level)) - pa); 2264 #endif 2265 } else if (object->memattr == VM_MEMATTR_DEFAULT && 2266 m->queue != PQ_NONE && !vm_page_busied(m)) { 2267 /* 2268 * The page is allocated but eligible for 2269 * relocation. Extend the current run by one 2270 * page. 2271 */ 2272 KASSERT(pmap_page_get_memattr(m) == 2273 VM_MEMATTR_DEFAULT, 2274 ("page %p has an unexpected memattr", m)); 2275 KASSERT((m->oflags & (VPO_SWAPINPROG | 2276 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, 2277 ("page %p has unexpected oflags", m)); 2278 /* Don't care: VPO_NOSYNC. */ 2279 run_ext = 1; 2280 } else 2281 run_ext = 0; 2282 unlock: 2283 VM_OBJECT_RUNLOCK(object); 2284 #if VM_NRESERVLEVEL > 0 2285 } else if (level >= 0) { 2286 /* 2287 * The page is reserved but not yet allocated. In 2288 * other words, it is still cached or free. Extend 2289 * the current run by one page. 2290 */ 2291 run_ext = 1; 2292 #endif 2293 } else if ((order = m->order) < VM_NFREEORDER) { 2294 /* 2295 * The page is enqueued in the physical memory 2296 * allocator's cache/free page queues. Moreover, it 2297 * is the first page in a power-of-two-sized run of 2298 * contiguous cache/free pages. Add these pages to 2299 * the end of the current run, and jump ahead. 2300 */ 2301 run_ext = 1 << order; 2302 m_inc = 1 << order; 2303 } else { 2304 /* 2305 * Skip the page for one of the following reasons: (1) 2306 * It is enqueued in the physical memory allocator's 2307 * cache/free page queues. However, it is not the 2308 * first page in a run of contiguous cache/free pages. 2309 * (This case rarely occurs because the scan is 2310 * performed in ascending order.) (2) It is not 2311 * reserved, and it is transitioning from free to 2312 * allocated. (Conversely, the transition from 2313 * allocated to free for managed pages is blocked by 2314 * the page lock.) (3) It is allocated but not 2315 * contained by an object and not wired, e.g., 2316 * allocated by Xen's balloon driver. 2317 */ 2318 run_ext = 0; 2319 } 2320 2321 /* 2322 * Extend or reset the current run of pages. 2323 */ 2324 if (run_ext > 0) { 2325 if (run_len == 0) 2326 m_run = m; 2327 run_len += run_ext; 2328 } else { 2329 if (run_len > 0) { 2330 m_run = NULL; 2331 run_len = 0; 2332 } 2333 } 2334 } 2335 if (m_mtx != NULL) 2336 mtx_unlock(m_mtx); 2337 if (run_len >= npages) 2338 return (m_run); 2339 return (NULL); 2340 } 2341 2342 /* 2343 * vm_page_reclaim_run: 2344 * 2345 * Try to relocate each of the allocated virtual pages within the 2346 * specified run of physical pages to a new physical address. Free the 2347 * physical pages underlying the relocated virtual pages. A virtual page 2348 * is relocatable if and only if it could be laundered or reclaimed by 2349 * the page daemon. Whenever possible, a virtual page is relocated to a 2350 * physical address above "high". 2351 * 2352 * Returns 0 if every physical page within the run was already free or 2353 * just freed by a successful relocation. Otherwise, returns a non-zero 2354 * value indicating why the last attempt to relocate a virtual page was 2355 * unsuccessful. 2356 * 2357 * "req_class" must be an allocation class. 2358 */ 2359 static int 2360 vm_page_reclaim_run(int req_class, u_long npages, vm_page_t m_run, 2361 vm_paddr_t high) 2362 { 2363 struct mtx *m_mtx, *new_mtx; 2364 struct spglist free; 2365 vm_object_t object; 2366 vm_paddr_t pa; 2367 vm_page_t m, m_end, m_new; 2368 int error, order, req; 2369 2370 KASSERT((req_class & VM_ALLOC_CLASS_MASK) == req_class, 2371 ("req_class is not an allocation class")); 2372 SLIST_INIT(&free); 2373 error = 0; 2374 m = m_run; 2375 m_end = m_run + npages; 2376 m_mtx = NULL; 2377 for (; error == 0 && m < m_end; m++) { 2378 KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0, 2379 ("page %p is PG_FICTITIOUS or PG_MARKER", m)); 2380 2381 /* 2382 * Avoid releasing and reacquiring the same page lock. 2383 */ 2384 new_mtx = vm_page_lockptr(m); 2385 if (m_mtx != new_mtx) { 2386 if (m_mtx != NULL) 2387 mtx_unlock(m_mtx); 2388 m_mtx = new_mtx; 2389 mtx_lock(m_mtx); 2390 } 2391 retry: 2392 if (m->wire_count != 0 || m->hold_count != 0) 2393 error = EBUSY; 2394 else if ((object = m->object) != NULL) { 2395 /* 2396 * The page is relocated if and only if it could be 2397 * laundered or reclaimed by the page daemon. 2398 */ 2399 if (!VM_OBJECT_TRYWLOCK(object)) { 2400 mtx_unlock(m_mtx); 2401 VM_OBJECT_WLOCK(object); 2402 mtx_lock(m_mtx); 2403 if (m->object != object) { 2404 /* 2405 * The page may have been freed. 2406 */ 2407 VM_OBJECT_WUNLOCK(object); 2408 goto retry; 2409 } else if (m->wire_count != 0 || 2410 m->hold_count != 0) { 2411 error = EBUSY; 2412 goto unlock; 2413 } 2414 } 2415 KASSERT((m->flags & PG_UNHOLDFREE) == 0, 2416 ("page %p is PG_UNHOLDFREE", m)); 2417 /* Don't care: PG_NODUMP, PG_WINATCFLS, PG_ZERO. */ 2418 if (object->type != OBJT_DEFAULT && 2419 object->type != OBJT_SWAP && 2420 object->type != OBJT_VNODE) 2421 error = EINVAL; 2422 else if ((m->flags & PG_CACHED) != 0 || 2423 m != vm_page_lookup(object, m->pindex)) { 2424 /* 2425 * The page is cached or recently converted 2426 * from cached to free. 2427 */ 2428 VM_OBJECT_WUNLOCK(object); 2429 goto cached; 2430 } else if (object->memattr != VM_MEMATTR_DEFAULT) 2431 error = EINVAL; 2432 else if (m->queue != PQ_NONE && !vm_page_busied(m)) { 2433 KASSERT(pmap_page_get_memattr(m) == 2434 VM_MEMATTR_DEFAULT, 2435 ("page %p has an unexpected memattr", m)); 2436 KASSERT((m->oflags & (VPO_SWAPINPROG | 2437 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, 2438 ("page %p has unexpected oflags", m)); 2439 /* Don't care: VPO_NOSYNC. */ 2440 if (m->valid != 0) { 2441 /* 2442 * First, try to allocate a new page 2443 * that is above "high". Failing 2444 * that, try to allocate a new page 2445 * that is below "m_run". Allocate 2446 * the new page between the end of 2447 * "m_run" and "high" only as a last 2448 * resort. 2449 */ 2450 req = req_class | VM_ALLOC_NOOBJ; 2451 if ((m->flags & PG_NODUMP) != 0) 2452 req |= VM_ALLOC_NODUMP; 2453 if (trunc_page(high) != 2454 ~(vm_paddr_t)PAGE_MASK) { 2455 m_new = vm_page_alloc_contig( 2456 NULL, 0, req, 1, 2457 round_page(high), 2458 ~(vm_paddr_t)0, 2459 PAGE_SIZE, 0, 2460 VM_MEMATTR_DEFAULT); 2461 } else 2462 m_new = NULL; 2463 if (m_new == NULL) { 2464 pa = VM_PAGE_TO_PHYS(m_run); 2465 m_new = vm_page_alloc_contig( 2466 NULL, 0, req, 1, 2467 0, pa - 1, PAGE_SIZE, 0, 2468 VM_MEMATTR_DEFAULT); 2469 } 2470 if (m_new == NULL) { 2471 pa += ptoa(npages); 2472 m_new = vm_page_alloc_contig( 2473 NULL, 0, req, 1, 2474 pa, high, PAGE_SIZE, 0, 2475 VM_MEMATTR_DEFAULT); 2476 } 2477 if (m_new == NULL) { 2478 error = ENOMEM; 2479 goto unlock; 2480 } 2481 KASSERT(m_new->wire_count == 0, 2482 ("page %p is wired", m)); 2483 2484 /* 2485 * Replace "m" with the new page. For 2486 * vm_page_replace(), "m" must be busy 2487 * and dequeued. Finally, change "m" 2488 * as if vm_page_free() was called. 2489 */ 2490 if (object->ref_count != 0) 2491 pmap_remove_all(m); 2492 m_new->aflags = m->aflags; 2493 KASSERT(m_new->oflags == VPO_UNMANAGED, 2494 ("page %p is managed", m)); 2495 m_new->oflags = m->oflags & VPO_NOSYNC; 2496 pmap_copy_page(m, m_new); 2497 m_new->valid = m->valid; 2498 m_new->dirty = m->dirty; 2499 m->flags &= ~PG_ZERO; 2500 vm_page_xbusy(m); 2501 vm_page_remque(m); 2502 vm_page_replace_checked(m_new, object, 2503 m->pindex, m); 2504 m->valid = 0; 2505 vm_page_undirty(m); 2506 2507 /* 2508 * The new page must be deactivated 2509 * before the object is unlocked. 2510 */ 2511 new_mtx = vm_page_lockptr(m_new); 2512 if (m_mtx != new_mtx) { 2513 mtx_unlock(m_mtx); 2514 m_mtx = new_mtx; 2515 mtx_lock(m_mtx); 2516 } 2517 vm_page_deactivate(m_new); 2518 } else { 2519 m->flags &= ~PG_ZERO; 2520 vm_page_remque(m); 2521 vm_page_remove(m); 2522 KASSERT(m->dirty == 0, 2523 ("page %p is dirty", m)); 2524 } 2525 SLIST_INSERT_HEAD(&free, m, plinks.s.ss); 2526 } else 2527 error = EBUSY; 2528 unlock: 2529 VM_OBJECT_WUNLOCK(object); 2530 } else { 2531 cached: 2532 mtx_lock(&vm_page_queue_free_mtx); 2533 order = m->order; 2534 if (order < VM_NFREEORDER) { 2535 /* 2536 * The page is enqueued in the physical memory 2537 * allocator's cache/free page queues. 2538 * Moreover, it is the first page in a power- 2539 * of-two-sized run of contiguous cache/free 2540 * pages. Jump ahead to the last page within 2541 * that run, and continue from there. 2542 */ 2543 m += (1 << order) - 1; 2544 } 2545 #if VM_NRESERVLEVEL > 0 2546 else if (vm_reserv_is_page_free(m)) 2547 order = 0; 2548 #endif 2549 mtx_unlock(&vm_page_queue_free_mtx); 2550 if (order == VM_NFREEORDER) 2551 error = EINVAL; 2552 } 2553 } 2554 if (m_mtx != NULL) 2555 mtx_unlock(m_mtx); 2556 if ((m = SLIST_FIRST(&free)) != NULL) { 2557 mtx_lock(&vm_page_queue_free_mtx); 2558 do { 2559 SLIST_REMOVE_HEAD(&free, plinks.s.ss); 2560 vm_phys_freecnt_adj(m, 1); 2561 #if VM_NRESERVLEVEL > 0 2562 if (!vm_reserv_free_page(m)) 2563 #else 2564 if (true) 2565 #endif 2566 vm_phys_free_pages(m, 0); 2567 } while ((m = SLIST_FIRST(&free)) != NULL); 2568 vm_page_zero_idle_wakeup(); 2569 vm_page_free_wakeup(); 2570 mtx_unlock(&vm_page_queue_free_mtx); 2571 } 2572 return (error); 2573 } 2574 2575 #define NRUNS 16 2576 2577 CTASSERT(powerof2(NRUNS)); 2578 2579 #define RUN_INDEX(count) ((count) & (NRUNS - 1)) 2580 2581 #define MIN_RECLAIM 8 2582 2583 /* 2584 * vm_page_reclaim_contig: 2585 * 2586 * Reclaim allocated, contiguous physical memory satisfying the specified 2587 * conditions by relocating the virtual pages using that physical memory. 2588 * Returns true if reclamation is successful and false otherwise. Since 2589 * relocation requires the allocation of physical pages, reclamation may 2590 * fail due to a shortage of cache/free pages. When reclamation fails, 2591 * callers are expected to perform VM_WAIT before retrying a failed 2592 * allocation operation, e.g., vm_page_alloc_contig(). 2593 * 2594 * The caller must always specify an allocation class through "req". 2595 * 2596 * allocation classes: 2597 * VM_ALLOC_NORMAL normal process request 2598 * VM_ALLOC_SYSTEM system *really* needs a page 2599 * VM_ALLOC_INTERRUPT interrupt time request 2600 * 2601 * The optional allocation flags are ignored. 2602 * 2603 * "npages" must be greater than zero. Both "alignment" and "boundary" 2604 * must be a power of two. 2605 */ 2606 bool 2607 vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low, vm_paddr_t high, 2608 u_long alignment, vm_paddr_t boundary) 2609 { 2610 vm_paddr_t curr_low; 2611 vm_page_t m_run, m_runs[NRUNS]; 2612 u_long count, reclaimed; 2613 int error, i, options, req_class; 2614 2615 KASSERT(npages > 0, ("npages is 0")); 2616 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 2617 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 2618 req_class = req & VM_ALLOC_CLASS_MASK; 2619 2620 /* 2621 * The page daemon is allowed to dig deeper into the free page list. 2622 */ 2623 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 2624 req_class = VM_ALLOC_SYSTEM; 2625 2626 /* 2627 * Return if the number of cached and free pages cannot satisfy the 2628 * requested allocation. 2629 */ 2630 count = vm_cnt.v_free_count + vm_cnt.v_cache_count; 2631 if (count < npages + vm_cnt.v_free_reserved || (count < npages + 2632 vm_cnt.v_interrupt_free_min && req_class == VM_ALLOC_SYSTEM) || 2633 (count < npages && req_class == VM_ALLOC_INTERRUPT)) 2634 return (false); 2635 2636 /* 2637 * Scan up to three times, relaxing the restrictions ("options") on 2638 * the reclamation of reservations and superpages each time. 2639 */ 2640 for (options = VPSC_NORESERV;;) { 2641 /* 2642 * Find the highest runs that satisfy the given constraints 2643 * and restrictions, and record them in "m_runs". 2644 */ 2645 curr_low = low; 2646 count = 0; 2647 for (;;) { 2648 m_run = vm_phys_scan_contig(npages, curr_low, high, 2649 alignment, boundary, options); 2650 if (m_run == NULL) 2651 break; 2652 curr_low = VM_PAGE_TO_PHYS(m_run) + ptoa(npages); 2653 m_runs[RUN_INDEX(count)] = m_run; 2654 count++; 2655 } 2656 2657 /* 2658 * Reclaim the highest runs in LIFO (descending) order until 2659 * the number of reclaimed pages, "reclaimed", is at least 2660 * MIN_RECLAIM. Reset "reclaimed" each time because each 2661 * reclamation is idempotent, and runs will (likely) recur 2662 * from one scan to the next as restrictions are relaxed. 2663 */ 2664 reclaimed = 0; 2665 for (i = 0; count > 0 && i < NRUNS; i++) { 2666 count--; 2667 m_run = m_runs[RUN_INDEX(count)]; 2668 error = vm_page_reclaim_run(req_class, npages, m_run, 2669 high); 2670 if (error == 0) { 2671 reclaimed += npages; 2672 if (reclaimed >= MIN_RECLAIM) 2673 return (true); 2674 } 2675 } 2676 2677 /* 2678 * Either relax the restrictions on the next scan or return if 2679 * the last scan had no restrictions. 2680 */ 2681 if (options == VPSC_NORESERV) 2682 options = VPSC_NOSUPER; 2683 else if (options == VPSC_NOSUPER) 2684 options = VPSC_ANY; 2685 else if (options == VPSC_ANY) 2686 return (reclaimed != 0); 2687 } 2688 } 2689 2690 /* 2691 * vm_wait: (also see VM_WAIT macro) 2692 * 2693 * Sleep until free pages are available for allocation. 2694 * - Called in various places before memory allocations. 2695 */ 2696 void 2697 vm_wait(void) 2698 { 2699 2700 mtx_lock(&vm_page_queue_free_mtx); 2701 if (curproc == pageproc) { 2702 vm_pageout_pages_needed = 1; 2703 msleep(&vm_pageout_pages_needed, &vm_page_queue_free_mtx, 2704 PDROP | PSWP, "VMWait", 0); 2705 } else { 2706 if (!vm_pageout_wanted) { 2707 vm_pageout_wanted = true; 2708 wakeup(&vm_pageout_wanted); 2709 } 2710 vm_pages_needed = true; 2711 msleep(&vm_cnt.v_free_count, &vm_page_queue_free_mtx, PDROP | PVM, 2712 "vmwait", 0); 2713 } 2714 } 2715 2716 /* 2717 * vm_waitpfault: (also see VM_WAITPFAULT macro) 2718 * 2719 * Sleep until free pages are available for allocation. 2720 * - Called only in vm_fault so that processes page faulting 2721 * can be easily tracked. 2722 * - Sleeps at a lower priority than vm_wait() so that vm_wait()ing 2723 * processes will be able to grab memory first. Do not change 2724 * this balance without careful testing first. 2725 */ 2726 void 2727 vm_waitpfault(void) 2728 { 2729 2730 mtx_lock(&vm_page_queue_free_mtx); 2731 if (!vm_pageout_wanted) { 2732 vm_pageout_wanted = true; 2733 wakeup(&vm_pageout_wanted); 2734 } 2735 vm_pages_needed = true; 2736 msleep(&vm_cnt.v_free_count, &vm_page_queue_free_mtx, PDROP | PUSER, 2737 "pfault", 0); 2738 } 2739 2740 struct vm_pagequeue * 2741 vm_page_pagequeue(vm_page_t m) 2742 { 2743 2744 return (&vm_phys_domain(m)->vmd_pagequeues[m->queue]); 2745 } 2746 2747 /* 2748 * vm_page_dequeue: 2749 * 2750 * Remove the given page from its current page queue. 2751 * 2752 * The page must be locked. 2753 */ 2754 void 2755 vm_page_dequeue(vm_page_t m) 2756 { 2757 struct vm_pagequeue *pq; 2758 2759 vm_page_assert_locked(m); 2760 KASSERT(m->queue < PQ_COUNT, ("vm_page_dequeue: page %p is not queued", 2761 m)); 2762 pq = vm_page_pagequeue(m); 2763 vm_pagequeue_lock(pq); 2764 m->queue = PQ_NONE; 2765 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2766 vm_pagequeue_cnt_dec(pq); 2767 vm_pagequeue_unlock(pq); 2768 } 2769 2770 /* 2771 * vm_page_dequeue_locked: 2772 * 2773 * Remove the given page from its current page queue. 2774 * 2775 * The page and page queue must be locked. 2776 */ 2777 void 2778 vm_page_dequeue_locked(vm_page_t m) 2779 { 2780 struct vm_pagequeue *pq; 2781 2782 vm_page_lock_assert(m, MA_OWNED); 2783 pq = vm_page_pagequeue(m); 2784 vm_pagequeue_assert_locked(pq); 2785 m->queue = PQ_NONE; 2786 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2787 vm_pagequeue_cnt_dec(pq); 2788 } 2789 2790 /* 2791 * vm_page_enqueue: 2792 * 2793 * Add the given page to the specified page queue. 2794 * 2795 * The page must be locked. 2796 */ 2797 static void 2798 vm_page_enqueue(uint8_t queue, vm_page_t m) 2799 { 2800 struct vm_pagequeue *pq; 2801 2802 vm_page_lock_assert(m, MA_OWNED); 2803 KASSERT(queue < PQ_COUNT, 2804 ("vm_page_enqueue: invalid queue %u request for page %p", 2805 queue, m)); 2806 pq = &vm_phys_domain(m)->vmd_pagequeues[queue]; 2807 vm_pagequeue_lock(pq); 2808 m->queue = queue; 2809 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 2810 vm_pagequeue_cnt_inc(pq); 2811 vm_pagequeue_unlock(pq); 2812 } 2813 2814 /* 2815 * vm_page_requeue: 2816 * 2817 * Move the given page to the tail of its current page queue. 2818 * 2819 * The page must be locked. 2820 */ 2821 void 2822 vm_page_requeue(vm_page_t m) 2823 { 2824 struct vm_pagequeue *pq; 2825 2826 vm_page_lock_assert(m, MA_OWNED); 2827 KASSERT(m->queue != PQ_NONE, 2828 ("vm_page_requeue: page %p is not queued", m)); 2829 pq = vm_page_pagequeue(m); 2830 vm_pagequeue_lock(pq); 2831 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2832 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 2833 vm_pagequeue_unlock(pq); 2834 } 2835 2836 /* 2837 * vm_page_requeue_locked: 2838 * 2839 * Move the given page to the tail of its current page queue. 2840 * 2841 * The page queue must be locked. 2842 */ 2843 void 2844 vm_page_requeue_locked(vm_page_t m) 2845 { 2846 struct vm_pagequeue *pq; 2847 2848 KASSERT(m->queue != PQ_NONE, 2849 ("vm_page_requeue_locked: page %p is not queued", m)); 2850 pq = vm_page_pagequeue(m); 2851 vm_pagequeue_assert_locked(pq); 2852 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2853 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 2854 } 2855 2856 /* 2857 * vm_page_activate: 2858 * 2859 * Put the specified page on the active list (if appropriate). 2860 * Ensure that act_count is at least ACT_INIT but do not otherwise 2861 * mess with it. 2862 * 2863 * The page must be locked. 2864 */ 2865 void 2866 vm_page_activate(vm_page_t m) 2867 { 2868 int queue; 2869 2870 vm_page_lock_assert(m, MA_OWNED); 2871 if ((queue = m->queue) != PQ_ACTIVE) { 2872 if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) { 2873 if (m->act_count < ACT_INIT) 2874 m->act_count = ACT_INIT; 2875 if (queue != PQ_NONE) 2876 vm_page_dequeue(m); 2877 vm_page_enqueue(PQ_ACTIVE, m); 2878 } else 2879 KASSERT(queue == PQ_NONE, 2880 ("vm_page_activate: wired page %p is queued", m)); 2881 } else { 2882 if (m->act_count < ACT_INIT) 2883 m->act_count = ACT_INIT; 2884 } 2885 } 2886 2887 /* 2888 * vm_page_free_wakeup: 2889 * 2890 * Helper routine for vm_page_free_toq() and vm_page_cache(). This 2891 * routine is called when a page has been added to the cache or free 2892 * queues. 2893 * 2894 * The page queues must be locked. 2895 */ 2896 static inline void 2897 vm_page_free_wakeup(void) 2898 { 2899 2900 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 2901 /* 2902 * if pageout daemon needs pages, then tell it that there are 2903 * some free. 2904 */ 2905 if (vm_pageout_pages_needed && 2906 vm_cnt.v_cache_count + vm_cnt.v_free_count >= vm_cnt.v_pageout_free_min) { 2907 wakeup(&vm_pageout_pages_needed); 2908 vm_pageout_pages_needed = 0; 2909 } 2910 /* 2911 * wakeup processes that are waiting on memory if we hit a 2912 * high water mark. And wakeup scheduler process if we have 2913 * lots of memory. this process will swapin processes. 2914 */ 2915 if (vm_pages_needed && !vm_page_count_min()) { 2916 vm_pages_needed = false; 2917 wakeup(&vm_cnt.v_free_count); 2918 } 2919 } 2920 2921 /* 2922 * Turn a cached page into a free page, by changing its attributes. 2923 * Keep the statistics up-to-date. 2924 * 2925 * The free page queue must be locked. 2926 */ 2927 static void 2928 vm_page_cache_turn_free(vm_page_t m) 2929 { 2930 2931 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 2932 2933 m->object = NULL; 2934 m->valid = 0; 2935 KASSERT((m->flags & PG_CACHED) != 0, 2936 ("vm_page_cache_turn_free: page %p is not cached", m)); 2937 m->flags &= ~PG_CACHED; 2938 vm_cnt.v_cache_count--; 2939 vm_phys_freecnt_adj(m, 1); 2940 } 2941 2942 /* 2943 * vm_page_free_toq: 2944 * 2945 * Returns the given page to the free list, 2946 * disassociating it with any VM object. 2947 * 2948 * The object must be locked. The page must be locked if it is managed. 2949 */ 2950 void 2951 vm_page_free_toq(vm_page_t m) 2952 { 2953 2954 if ((m->oflags & VPO_UNMANAGED) == 0) { 2955 vm_page_lock_assert(m, MA_OWNED); 2956 KASSERT(!pmap_page_is_mapped(m), 2957 ("vm_page_free_toq: freeing mapped page %p", m)); 2958 } else 2959 KASSERT(m->queue == PQ_NONE, 2960 ("vm_page_free_toq: unmanaged page %p is queued", m)); 2961 PCPU_INC(cnt.v_tfree); 2962 2963 if (vm_page_sbusied(m)) 2964 panic("vm_page_free: freeing busy page %p", m); 2965 2966 /* 2967 * Unqueue, then remove page. Note that we cannot destroy 2968 * the page here because we do not want to call the pager's 2969 * callback routine until after we've put the page on the 2970 * appropriate free queue. 2971 */ 2972 vm_page_remque(m); 2973 vm_page_remove(m); 2974 2975 /* 2976 * If fictitious remove object association and 2977 * return, otherwise delay object association removal. 2978 */ 2979 if ((m->flags & PG_FICTITIOUS) != 0) { 2980 return; 2981 } 2982 2983 m->valid = 0; 2984 vm_page_undirty(m); 2985 2986 if (m->wire_count != 0) 2987 panic("vm_page_free: freeing wired page %p", m); 2988 if (m->hold_count != 0) { 2989 m->flags &= ~PG_ZERO; 2990 KASSERT((m->flags & PG_UNHOLDFREE) == 0, 2991 ("vm_page_free: freeing PG_UNHOLDFREE page %p", m)); 2992 m->flags |= PG_UNHOLDFREE; 2993 } else { 2994 /* 2995 * Restore the default memory attribute to the page. 2996 */ 2997 if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT) 2998 pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT); 2999 3000 /* 3001 * Insert the page into the physical memory allocator's 3002 * cache/free page queues. 3003 */ 3004 mtx_lock(&vm_page_queue_free_mtx); 3005 vm_phys_freecnt_adj(m, 1); 3006 #if VM_NRESERVLEVEL > 0 3007 if (!vm_reserv_free_page(m)) 3008 #else 3009 if (TRUE) 3010 #endif 3011 vm_phys_free_pages(m, 0); 3012 if ((m->flags & PG_ZERO) != 0) 3013 ++vm_page_zero_count; 3014 else 3015 vm_page_zero_idle_wakeup(); 3016 vm_page_free_wakeup(); 3017 mtx_unlock(&vm_page_queue_free_mtx); 3018 } 3019 } 3020 3021 /* 3022 * vm_page_wire: 3023 * 3024 * Mark this page as wired down by yet 3025 * another map, removing it from paging queues 3026 * as necessary. 3027 * 3028 * If the page is fictitious, then its wire count must remain one. 3029 * 3030 * The page must be locked. 3031 */ 3032 void 3033 vm_page_wire(vm_page_t m) 3034 { 3035 3036 /* 3037 * Only bump the wire statistics if the page is not already wired, 3038 * and only unqueue the page if it is on some queue (if it is unmanaged 3039 * it is already off the queues). 3040 */ 3041 vm_page_lock_assert(m, MA_OWNED); 3042 if ((m->flags & PG_FICTITIOUS) != 0) { 3043 KASSERT(m->wire_count == 1, 3044 ("vm_page_wire: fictitious page %p's wire count isn't one", 3045 m)); 3046 return; 3047 } 3048 if (m->wire_count == 0) { 3049 KASSERT((m->oflags & VPO_UNMANAGED) == 0 || 3050 m->queue == PQ_NONE, 3051 ("vm_page_wire: unmanaged page %p is queued", m)); 3052 vm_page_remque(m); 3053 atomic_add_int(&vm_cnt.v_wire_count, 1); 3054 } 3055 m->wire_count++; 3056 KASSERT(m->wire_count != 0, ("vm_page_wire: wire_count overflow m=%p", m)); 3057 } 3058 3059 /* 3060 * vm_page_unwire: 3061 * 3062 * Release one wiring of the specified page, potentially allowing it to be 3063 * paged out. Returns TRUE if the number of wirings transitions to zero and 3064 * FALSE otherwise. 3065 * 3066 * Only managed pages belonging to an object can be paged out. If the number 3067 * of wirings transitions to zero and the page is eligible for page out, then 3068 * the page is added to the specified paging queue (unless PQ_NONE is 3069 * specified). 3070 * 3071 * If a page is fictitious, then its wire count must always be one. 3072 * 3073 * A managed page must be locked. 3074 */ 3075 boolean_t 3076 vm_page_unwire(vm_page_t m, uint8_t queue) 3077 { 3078 3079 KASSERT(queue < PQ_COUNT || queue == PQ_NONE, 3080 ("vm_page_unwire: invalid queue %u request for page %p", 3081 queue, m)); 3082 if ((m->oflags & VPO_UNMANAGED) == 0) 3083 vm_page_assert_locked(m); 3084 if ((m->flags & PG_FICTITIOUS) != 0) { 3085 KASSERT(m->wire_count == 1, 3086 ("vm_page_unwire: fictitious page %p's wire count isn't one", m)); 3087 return (FALSE); 3088 } 3089 if (m->wire_count > 0) { 3090 m->wire_count--; 3091 if (m->wire_count == 0) { 3092 atomic_subtract_int(&vm_cnt.v_wire_count, 1); 3093 if ((m->oflags & VPO_UNMANAGED) == 0 && 3094 m->object != NULL && queue != PQ_NONE) { 3095 if (queue == PQ_INACTIVE) 3096 m->flags &= ~PG_WINATCFLS; 3097 vm_page_enqueue(queue, m); 3098 } 3099 return (TRUE); 3100 } else 3101 return (FALSE); 3102 } else 3103 panic("vm_page_unwire: page %p's wire count is zero", m); 3104 } 3105 3106 /* 3107 * Move the specified page to the inactive queue. 3108 * 3109 * Many pages placed on the inactive queue should actually go 3110 * into the cache, but it is difficult to figure out which. What 3111 * we do instead, if the inactive target is well met, is to put 3112 * clean pages at the head of the inactive queue instead of the tail. 3113 * This will cause them to be moved to the cache more quickly and 3114 * if not actively re-referenced, reclaimed more quickly. If we just 3115 * stick these pages at the end of the inactive queue, heavy filesystem 3116 * meta-data accesses can cause an unnecessary paging load on memory bound 3117 * processes. This optimization causes one-time-use metadata to be 3118 * reused more quickly. 3119 * 3120 * Normally noreuse is FALSE, resulting in LRU operation. noreuse is set 3121 * to TRUE if we want this page to be 'as if it were placed in the cache', 3122 * except without unmapping it from the process address space. In 3123 * practice this is implemented by inserting the page at the head of the 3124 * queue, using a marker page to guide FIFO insertion ordering. 3125 * 3126 * The page must be locked. 3127 */ 3128 static inline void 3129 _vm_page_deactivate(vm_page_t m, boolean_t noreuse) 3130 { 3131 struct vm_pagequeue *pq; 3132 int queue; 3133 3134 vm_page_assert_locked(m); 3135 3136 /* 3137 * Ignore if the page is already inactive, unless it is unlikely to be 3138 * reactivated. 3139 */ 3140 if ((queue = m->queue) == PQ_INACTIVE && !noreuse) 3141 return; 3142 if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) { 3143 pq = &vm_phys_domain(m)->vmd_pagequeues[PQ_INACTIVE]; 3144 /* Avoid multiple acquisitions of the inactive queue lock. */ 3145 if (queue == PQ_INACTIVE) { 3146 vm_pagequeue_lock(pq); 3147 vm_page_dequeue_locked(m); 3148 } else { 3149 if (queue != PQ_NONE) 3150 vm_page_dequeue(m); 3151 m->flags &= ~PG_WINATCFLS; 3152 vm_pagequeue_lock(pq); 3153 } 3154 m->queue = PQ_INACTIVE; 3155 if (noreuse) 3156 TAILQ_INSERT_BEFORE(&vm_phys_domain(m)->vmd_inacthead, 3157 m, plinks.q); 3158 else 3159 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 3160 vm_pagequeue_cnt_inc(pq); 3161 vm_pagequeue_unlock(pq); 3162 } 3163 } 3164 3165 /* 3166 * Move the specified page to the inactive queue. 3167 * 3168 * The page must be locked. 3169 */ 3170 void 3171 vm_page_deactivate(vm_page_t m) 3172 { 3173 3174 _vm_page_deactivate(m, FALSE); 3175 } 3176 3177 /* 3178 * Move the specified page to the inactive queue with the expectation 3179 * that it is unlikely to be reused. 3180 * 3181 * The page must be locked. 3182 */ 3183 void 3184 vm_page_deactivate_noreuse(vm_page_t m) 3185 { 3186 3187 _vm_page_deactivate(m, TRUE); 3188 } 3189 3190 /* 3191 * vm_page_try_to_cache: 3192 * 3193 * Returns 0 on failure, 1 on success 3194 */ 3195 int 3196 vm_page_try_to_cache(vm_page_t m) 3197 { 3198 3199 vm_page_lock_assert(m, MA_OWNED); 3200 VM_OBJECT_ASSERT_WLOCKED(m->object); 3201 if (m->dirty || m->hold_count || m->wire_count || 3202 (m->oflags & VPO_UNMANAGED) != 0 || vm_page_busied(m)) 3203 return (0); 3204 pmap_remove_all(m); 3205 if (m->dirty) 3206 return (0); 3207 vm_page_cache(m); 3208 return (1); 3209 } 3210 3211 /* 3212 * vm_page_try_to_free() 3213 * 3214 * Attempt to free the page. If we cannot free it, we do nothing. 3215 * 1 is returned on success, 0 on failure. 3216 */ 3217 int 3218 vm_page_try_to_free(vm_page_t m) 3219 { 3220 3221 vm_page_lock_assert(m, MA_OWNED); 3222 if (m->object != NULL) 3223 VM_OBJECT_ASSERT_WLOCKED(m->object); 3224 if (m->dirty || m->hold_count || m->wire_count || 3225 (m->oflags & VPO_UNMANAGED) != 0 || vm_page_busied(m)) 3226 return (0); 3227 pmap_remove_all(m); 3228 if (m->dirty) 3229 return (0); 3230 vm_page_free(m); 3231 return (1); 3232 } 3233 3234 /* 3235 * vm_page_cache 3236 * 3237 * Put the specified page onto the page cache queue (if appropriate). 3238 * 3239 * The object and page must be locked. 3240 */ 3241 void 3242 vm_page_cache(vm_page_t m) 3243 { 3244 vm_object_t object; 3245 boolean_t cache_was_empty; 3246 3247 vm_page_lock_assert(m, MA_OWNED); 3248 object = m->object; 3249 VM_OBJECT_ASSERT_WLOCKED(object); 3250 if (vm_page_busied(m) || (m->oflags & VPO_UNMANAGED) || 3251 m->hold_count || m->wire_count) 3252 panic("vm_page_cache: attempting to cache busy page"); 3253 KASSERT(!pmap_page_is_mapped(m), 3254 ("vm_page_cache: page %p is mapped", m)); 3255 KASSERT(m->dirty == 0, ("vm_page_cache: page %p is dirty", m)); 3256 if (m->valid == 0 || object->type == OBJT_DEFAULT || 3257 (object->type == OBJT_SWAP && 3258 !vm_pager_has_page(object, m->pindex, NULL, NULL))) { 3259 /* 3260 * Hypothesis: A cache-eligible page belonging to a 3261 * default object or swap object but without a backing 3262 * store must be zero filled. 3263 */ 3264 vm_page_free(m); 3265 return; 3266 } 3267 KASSERT((m->flags & PG_CACHED) == 0, 3268 ("vm_page_cache: page %p is already cached", m)); 3269 3270 /* 3271 * Remove the page from the paging queues. 3272 */ 3273 vm_page_remque(m); 3274 3275 /* 3276 * Remove the page from the object's collection of resident 3277 * pages. 3278 */ 3279 vm_radix_remove(&object->rtree, m->pindex); 3280 TAILQ_REMOVE(&object->memq, m, listq); 3281 object->resident_page_count--; 3282 3283 /* 3284 * Restore the default memory attribute to the page. 3285 */ 3286 if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT) 3287 pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT); 3288 3289 /* 3290 * Insert the page into the object's collection of cached pages 3291 * and the physical memory allocator's cache/free page queues. 3292 */ 3293 m->flags &= ~PG_ZERO; 3294 mtx_lock(&vm_page_queue_free_mtx); 3295 cache_was_empty = vm_radix_is_empty(&object->cache); 3296 if (vm_radix_insert(&object->cache, m)) { 3297 mtx_unlock(&vm_page_queue_free_mtx); 3298 if (object->type == OBJT_VNODE && 3299 object->resident_page_count == 0) 3300 vdrop(object->handle); 3301 m->object = NULL; 3302 vm_page_free(m); 3303 return; 3304 } 3305 3306 /* 3307 * The above call to vm_radix_insert() could reclaim the one pre- 3308 * existing cached page from this object, resulting in a call to 3309 * vdrop(). 3310 */ 3311 if (!cache_was_empty) 3312 cache_was_empty = vm_radix_is_singleton(&object->cache); 3313 3314 m->flags |= PG_CACHED; 3315 vm_cnt.v_cache_count++; 3316 PCPU_INC(cnt.v_tcached); 3317 #if VM_NRESERVLEVEL > 0 3318 if (!vm_reserv_free_page(m)) { 3319 #else 3320 if (TRUE) { 3321 #endif 3322 vm_phys_free_pages(m, 0); 3323 } 3324 vm_page_free_wakeup(); 3325 mtx_unlock(&vm_page_queue_free_mtx); 3326 3327 /* 3328 * Increment the vnode's hold count if this is the object's only 3329 * cached page. Decrement the vnode's hold count if this was 3330 * the object's only resident page. 3331 */ 3332 if (object->type == OBJT_VNODE) { 3333 if (cache_was_empty && object->resident_page_count != 0) 3334 vhold(object->handle); 3335 else if (!cache_was_empty && object->resident_page_count == 0) 3336 vdrop(object->handle); 3337 } 3338 } 3339 3340 /* 3341 * vm_page_advise 3342 * 3343 * Deactivate or do nothing, as appropriate. 3344 * 3345 * The object and page must be locked. 3346 */ 3347 void 3348 vm_page_advise(vm_page_t m, int advice) 3349 { 3350 3351 vm_page_assert_locked(m); 3352 VM_OBJECT_ASSERT_WLOCKED(m->object); 3353 if (advice == MADV_FREE) 3354 /* 3355 * Mark the page clean. This will allow the page to be freed 3356 * up by the system. However, such pages are often reused 3357 * quickly by malloc() so we do not do anything that would 3358 * cause a page fault if we can help it. 3359 * 3360 * Specifically, we do not try to actually free the page now 3361 * nor do we try to put it in the cache (which would cause a 3362 * page fault on reuse). 3363 * 3364 * But we do make the page as freeable as we can without 3365 * actually taking the step of unmapping it. 3366 */ 3367 m->dirty = 0; 3368 else if (advice != MADV_DONTNEED) 3369 return; 3370 3371 /* 3372 * Clear any references to the page. Otherwise, the page daemon will 3373 * immediately reactivate the page. 3374 */ 3375 vm_page_aflag_clear(m, PGA_REFERENCED); 3376 3377 if (advice != MADV_FREE && m->dirty == 0 && pmap_is_modified(m)) 3378 vm_page_dirty(m); 3379 3380 /* 3381 * Place clean pages at the head of the inactive queue rather than the 3382 * tail, thus defeating the queue's LRU operation and ensuring that the 3383 * page will be reused quickly. 3384 */ 3385 _vm_page_deactivate(m, m->dirty == 0); 3386 } 3387 3388 /* 3389 * Grab a page, waiting until we are waken up due to the page 3390 * changing state. We keep on waiting, if the page continues 3391 * to be in the object. If the page doesn't exist, first allocate it 3392 * and then conditionally zero it. 3393 * 3394 * This routine may sleep. 3395 * 3396 * The object must be locked on entry. The lock will, however, be released 3397 * and reacquired if the routine sleeps. 3398 */ 3399 vm_page_t 3400 vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags) 3401 { 3402 vm_page_t m; 3403 int sleep; 3404 3405 VM_OBJECT_ASSERT_WLOCKED(object); 3406 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || 3407 (allocflags & VM_ALLOC_IGN_SBUSY) != 0, 3408 ("vm_page_grab: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch")); 3409 retrylookup: 3410 if ((m = vm_page_lookup(object, pindex)) != NULL) { 3411 sleep = (allocflags & VM_ALLOC_IGN_SBUSY) != 0 ? 3412 vm_page_xbusied(m) : vm_page_busied(m); 3413 if (sleep) { 3414 if ((allocflags & VM_ALLOC_NOWAIT) != 0) 3415 return (NULL); 3416 /* 3417 * Reference the page before unlocking and 3418 * sleeping so that the page daemon is less 3419 * likely to reclaim it. 3420 */ 3421 vm_page_aflag_set(m, PGA_REFERENCED); 3422 vm_page_lock(m); 3423 VM_OBJECT_WUNLOCK(object); 3424 vm_page_busy_sleep(m, "pgrbwt"); 3425 VM_OBJECT_WLOCK(object); 3426 goto retrylookup; 3427 } else { 3428 if ((allocflags & VM_ALLOC_WIRED) != 0) { 3429 vm_page_lock(m); 3430 vm_page_wire(m); 3431 vm_page_unlock(m); 3432 } 3433 if ((allocflags & 3434 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0) 3435 vm_page_xbusy(m); 3436 if ((allocflags & VM_ALLOC_SBUSY) != 0) 3437 vm_page_sbusy(m); 3438 return (m); 3439 } 3440 } 3441 m = vm_page_alloc(object, pindex, allocflags); 3442 if (m == NULL) { 3443 if ((allocflags & VM_ALLOC_NOWAIT) != 0) 3444 return (NULL); 3445 VM_OBJECT_WUNLOCK(object); 3446 VM_WAIT; 3447 VM_OBJECT_WLOCK(object); 3448 goto retrylookup; 3449 } else if (m->valid != 0) 3450 return (m); 3451 if (allocflags & VM_ALLOC_ZERO && (m->flags & PG_ZERO) == 0) 3452 pmap_zero_page(m); 3453 return (m); 3454 } 3455 3456 /* 3457 * Mapping function for valid or dirty bits in a page. 3458 * 3459 * Inputs are required to range within a page. 3460 */ 3461 vm_page_bits_t 3462 vm_page_bits(int base, int size) 3463 { 3464 int first_bit; 3465 int last_bit; 3466 3467 KASSERT( 3468 base + size <= PAGE_SIZE, 3469 ("vm_page_bits: illegal base/size %d/%d", base, size) 3470 ); 3471 3472 if (size == 0) /* handle degenerate case */ 3473 return (0); 3474 3475 first_bit = base >> DEV_BSHIFT; 3476 last_bit = (base + size - 1) >> DEV_BSHIFT; 3477 3478 return (((vm_page_bits_t)2 << last_bit) - 3479 ((vm_page_bits_t)1 << first_bit)); 3480 } 3481 3482 /* 3483 * vm_page_set_valid_range: 3484 * 3485 * Sets portions of a page valid. The arguments are expected 3486 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive 3487 * of any partial chunks touched by the range. The invalid portion of 3488 * such chunks will be zeroed. 3489 * 3490 * (base + size) must be less then or equal to PAGE_SIZE. 3491 */ 3492 void 3493 vm_page_set_valid_range(vm_page_t m, int base, int size) 3494 { 3495 int endoff, frag; 3496 3497 VM_OBJECT_ASSERT_WLOCKED(m->object); 3498 if (size == 0) /* handle degenerate case */ 3499 return; 3500 3501 /* 3502 * If the base is not DEV_BSIZE aligned and the valid 3503 * bit is clear, we have to zero out a portion of the 3504 * first block. 3505 */ 3506 if ((frag = rounddown2(base, DEV_BSIZE)) != base && 3507 (m->valid & (1 << (base >> DEV_BSHIFT))) == 0) 3508 pmap_zero_page_area(m, frag, base - frag); 3509 3510 /* 3511 * If the ending offset is not DEV_BSIZE aligned and the 3512 * valid bit is clear, we have to zero out a portion of 3513 * the last block. 3514 */ 3515 endoff = base + size; 3516 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && 3517 (m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0) 3518 pmap_zero_page_area(m, endoff, 3519 DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); 3520 3521 /* 3522 * Assert that no previously invalid block that is now being validated 3523 * is already dirty. 3524 */ 3525 KASSERT((~m->valid & vm_page_bits(base, size) & m->dirty) == 0, 3526 ("vm_page_set_valid_range: page %p is dirty", m)); 3527 3528 /* 3529 * Set valid bits inclusive of any overlap. 3530 */ 3531 m->valid |= vm_page_bits(base, size); 3532 } 3533 3534 /* 3535 * Clear the given bits from the specified page's dirty field. 3536 */ 3537 static __inline void 3538 vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits) 3539 { 3540 uintptr_t addr; 3541 #if PAGE_SIZE < 16384 3542 int shift; 3543 #endif 3544 3545 /* 3546 * If the object is locked and the page is neither exclusive busy nor 3547 * write mapped, then the page's dirty field cannot possibly be 3548 * set by a concurrent pmap operation. 3549 */ 3550 VM_OBJECT_ASSERT_WLOCKED(m->object); 3551 if (!vm_page_xbusied(m) && !pmap_page_is_write_mapped(m)) 3552 m->dirty &= ~pagebits; 3553 else { 3554 /* 3555 * The pmap layer can call vm_page_dirty() without 3556 * holding a distinguished lock. The combination of 3557 * the object's lock and an atomic operation suffice 3558 * to guarantee consistency of the page dirty field. 3559 * 3560 * For PAGE_SIZE == 32768 case, compiler already 3561 * properly aligns the dirty field, so no forcible 3562 * alignment is needed. Only require existence of 3563 * atomic_clear_64 when page size is 32768. 3564 */ 3565 addr = (uintptr_t)&m->dirty; 3566 #if PAGE_SIZE == 32768 3567 atomic_clear_64((uint64_t *)addr, pagebits); 3568 #elif PAGE_SIZE == 16384 3569 atomic_clear_32((uint32_t *)addr, pagebits); 3570 #else /* PAGE_SIZE <= 8192 */ 3571 /* 3572 * Use a trick to perform a 32-bit atomic on the 3573 * containing aligned word, to not depend on the existence 3574 * of atomic_clear_{8, 16}. 3575 */ 3576 shift = addr & (sizeof(uint32_t) - 1); 3577 #if BYTE_ORDER == BIG_ENDIAN 3578 shift = (sizeof(uint32_t) - sizeof(m->dirty) - shift) * NBBY; 3579 #else 3580 shift *= NBBY; 3581 #endif 3582 addr &= ~(sizeof(uint32_t) - 1); 3583 atomic_clear_32((uint32_t *)addr, pagebits << shift); 3584 #endif /* PAGE_SIZE */ 3585 } 3586 } 3587 3588 /* 3589 * vm_page_set_validclean: 3590 * 3591 * Sets portions of a page valid and clean. The arguments are expected 3592 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive 3593 * of any partial chunks touched by the range. The invalid portion of 3594 * such chunks will be zero'd. 3595 * 3596 * (base + size) must be less then or equal to PAGE_SIZE. 3597 */ 3598 void 3599 vm_page_set_validclean(vm_page_t m, int base, int size) 3600 { 3601 vm_page_bits_t oldvalid, pagebits; 3602 int endoff, frag; 3603 3604 VM_OBJECT_ASSERT_WLOCKED(m->object); 3605 if (size == 0) /* handle degenerate case */ 3606 return; 3607 3608 /* 3609 * If the base is not DEV_BSIZE aligned and the valid 3610 * bit is clear, we have to zero out a portion of the 3611 * first block. 3612 */ 3613 if ((frag = rounddown2(base, DEV_BSIZE)) != base && 3614 (m->valid & ((vm_page_bits_t)1 << (base >> DEV_BSHIFT))) == 0) 3615 pmap_zero_page_area(m, frag, base - frag); 3616 3617 /* 3618 * If the ending offset is not DEV_BSIZE aligned and the 3619 * valid bit is clear, we have to zero out a portion of 3620 * the last block. 3621 */ 3622 endoff = base + size; 3623 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && 3624 (m->valid & ((vm_page_bits_t)1 << (endoff >> DEV_BSHIFT))) == 0) 3625 pmap_zero_page_area(m, endoff, 3626 DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); 3627 3628 /* 3629 * Set valid, clear dirty bits. If validating the entire 3630 * page we can safely clear the pmap modify bit. We also 3631 * use this opportunity to clear the VPO_NOSYNC flag. If a process 3632 * takes a write fault on a MAP_NOSYNC memory area the flag will 3633 * be set again. 3634 * 3635 * We set valid bits inclusive of any overlap, but we can only 3636 * clear dirty bits for DEV_BSIZE chunks that are fully within 3637 * the range. 3638 */ 3639 oldvalid = m->valid; 3640 pagebits = vm_page_bits(base, size); 3641 m->valid |= pagebits; 3642 #if 0 /* NOT YET */ 3643 if ((frag = base & (DEV_BSIZE - 1)) != 0) { 3644 frag = DEV_BSIZE - frag; 3645 base += frag; 3646 size -= frag; 3647 if (size < 0) 3648 size = 0; 3649 } 3650 pagebits = vm_page_bits(base, size & (DEV_BSIZE - 1)); 3651 #endif 3652 if (base == 0 && size == PAGE_SIZE) { 3653 /* 3654 * The page can only be modified within the pmap if it is 3655 * mapped, and it can only be mapped if it was previously 3656 * fully valid. 3657 */ 3658 if (oldvalid == VM_PAGE_BITS_ALL) 3659 /* 3660 * Perform the pmap_clear_modify() first. Otherwise, 3661 * a concurrent pmap operation, such as 3662 * pmap_protect(), could clear a modification in the 3663 * pmap and set the dirty field on the page before 3664 * pmap_clear_modify() had begun and after the dirty 3665 * field was cleared here. 3666 */ 3667 pmap_clear_modify(m); 3668 m->dirty = 0; 3669 m->oflags &= ~VPO_NOSYNC; 3670 } else if (oldvalid != VM_PAGE_BITS_ALL) 3671 m->dirty &= ~pagebits; 3672 else 3673 vm_page_clear_dirty_mask(m, pagebits); 3674 } 3675 3676 void 3677 vm_page_clear_dirty(vm_page_t m, int base, int size) 3678 { 3679 3680 vm_page_clear_dirty_mask(m, vm_page_bits(base, size)); 3681 } 3682 3683 /* 3684 * vm_page_set_invalid: 3685 * 3686 * Invalidates DEV_BSIZE'd chunks within a page. Both the 3687 * valid and dirty bits for the effected areas are cleared. 3688 */ 3689 void 3690 vm_page_set_invalid(vm_page_t m, int base, int size) 3691 { 3692 vm_page_bits_t bits; 3693 vm_object_t object; 3694 3695 object = m->object; 3696 VM_OBJECT_ASSERT_WLOCKED(object); 3697 if (object->type == OBJT_VNODE && base == 0 && IDX_TO_OFF(m->pindex) + 3698 size >= object->un_pager.vnp.vnp_size) 3699 bits = VM_PAGE_BITS_ALL; 3700 else 3701 bits = vm_page_bits(base, size); 3702 if (object->ref_count != 0 && m->valid == VM_PAGE_BITS_ALL && 3703 bits != 0) 3704 pmap_remove_all(m); 3705 KASSERT((bits == 0 && m->valid == VM_PAGE_BITS_ALL) || 3706 !pmap_page_is_mapped(m), 3707 ("vm_page_set_invalid: page %p is mapped", m)); 3708 m->valid &= ~bits; 3709 m->dirty &= ~bits; 3710 } 3711 3712 /* 3713 * vm_page_zero_invalid() 3714 * 3715 * The kernel assumes that the invalid portions of a page contain 3716 * garbage, but such pages can be mapped into memory by user code. 3717 * When this occurs, we must zero out the non-valid portions of the 3718 * page so user code sees what it expects. 3719 * 3720 * Pages are most often semi-valid when the end of a file is mapped 3721 * into memory and the file's size is not page aligned. 3722 */ 3723 void 3724 vm_page_zero_invalid(vm_page_t m, boolean_t setvalid) 3725 { 3726 int b; 3727 int i; 3728 3729 VM_OBJECT_ASSERT_WLOCKED(m->object); 3730 /* 3731 * Scan the valid bits looking for invalid sections that 3732 * must be zeroed. Invalid sub-DEV_BSIZE'd areas ( where the 3733 * valid bit may be set ) have already been zeroed by 3734 * vm_page_set_validclean(). 3735 */ 3736 for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) { 3737 if (i == (PAGE_SIZE / DEV_BSIZE) || 3738 (m->valid & ((vm_page_bits_t)1 << i))) { 3739 if (i > b) { 3740 pmap_zero_page_area(m, 3741 b << DEV_BSHIFT, (i - b) << DEV_BSHIFT); 3742 } 3743 b = i + 1; 3744 } 3745 } 3746 3747 /* 3748 * setvalid is TRUE when we can safely set the zero'd areas 3749 * as being valid. We can do this if there are no cache consistancy 3750 * issues. e.g. it is ok to do with UFS, but not ok to do with NFS. 3751 */ 3752 if (setvalid) 3753 m->valid = VM_PAGE_BITS_ALL; 3754 } 3755 3756 /* 3757 * vm_page_is_valid: 3758 * 3759 * Is (partial) page valid? Note that the case where size == 0 3760 * will return FALSE in the degenerate case where the page is 3761 * entirely invalid, and TRUE otherwise. 3762 */ 3763 int 3764 vm_page_is_valid(vm_page_t m, int base, int size) 3765 { 3766 vm_page_bits_t bits; 3767 3768 VM_OBJECT_ASSERT_LOCKED(m->object); 3769 bits = vm_page_bits(base, size); 3770 return (m->valid != 0 && (m->valid & bits) == bits); 3771 } 3772 3773 /* 3774 * vm_page_ps_is_valid: 3775 * 3776 * Returns TRUE if the entire (super)page is valid and FALSE otherwise. 3777 */ 3778 boolean_t 3779 vm_page_ps_is_valid(vm_page_t m) 3780 { 3781 int i, npages; 3782 3783 VM_OBJECT_ASSERT_LOCKED(m->object); 3784 npages = atop(pagesizes[m->psind]); 3785 3786 /* 3787 * The physically contiguous pages that make up a superpage, i.e., a 3788 * page with a page size index ("psind") greater than zero, will 3789 * occupy adjacent entries in vm_page_array[]. 3790 */ 3791 for (i = 0; i < npages; i++) { 3792 if (m[i].valid != VM_PAGE_BITS_ALL) 3793 return (FALSE); 3794 } 3795 return (TRUE); 3796 } 3797 3798 /* 3799 * Set the page's dirty bits if the page is modified. 3800 */ 3801 void 3802 vm_page_test_dirty(vm_page_t m) 3803 { 3804 3805 VM_OBJECT_ASSERT_WLOCKED(m->object); 3806 if (m->dirty != VM_PAGE_BITS_ALL && pmap_is_modified(m)) 3807 vm_page_dirty(m); 3808 } 3809 3810 void 3811 vm_page_lock_KBI(vm_page_t m, const char *file, int line) 3812 { 3813 3814 mtx_lock_flags_(vm_page_lockptr(m), 0, file, line); 3815 } 3816 3817 void 3818 vm_page_unlock_KBI(vm_page_t m, const char *file, int line) 3819 { 3820 3821 mtx_unlock_flags_(vm_page_lockptr(m), 0, file, line); 3822 } 3823 3824 int 3825 vm_page_trylock_KBI(vm_page_t m, const char *file, int line) 3826 { 3827 3828 return (mtx_trylock_flags_(vm_page_lockptr(m), 0, file, line)); 3829 } 3830 3831 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT) 3832 void 3833 vm_page_assert_locked_KBI(vm_page_t m, const char *file, int line) 3834 { 3835 3836 vm_page_lock_assert_KBI(m, MA_OWNED, file, line); 3837 } 3838 3839 void 3840 vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line) 3841 { 3842 3843 mtx_assert_(vm_page_lockptr(m), a, file, line); 3844 } 3845 #endif 3846 3847 #ifdef INVARIANTS 3848 void 3849 vm_page_object_lock_assert(vm_page_t m) 3850 { 3851 3852 /* 3853 * Certain of the page's fields may only be modified by the 3854 * holder of the containing object's lock or the exclusive busy. 3855 * holder. Unfortunately, the holder of the write busy is 3856 * not recorded, and thus cannot be checked here. 3857 */ 3858 if (m->object != NULL && !vm_page_xbusied(m)) 3859 VM_OBJECT_ASSERT_WLOCKED(m->object); 3860 } 3861 3862 void 3863 vm_page_assert_pga_writeable(vm_page_t m, uint8_t bits) 3864 { 3865 3866 if ((bits & PGA_WRITEABLE) == 0) 3867 return; 3868 3869 /* 3870 * The PGA_WRITEABLE flag can only be set if the page is 3871 * managed, is exclusively busied or the object is locked. 3872 * Currently, this flag is only set by pmap_enter(). 3873 */ 3874 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 3875 ("PGA_WRITEABLE on unmanaged page")); 3876 if (!vm_page_xbusied(m)) 3877 VM_OBJECT_ASSERT_LOCKED(m->object); 3878 } 3879 #endif 3880 3881 #include "opt_ddb.h" 3882 #ifdef DDB 3883 #include <sys/kernel.h> 3884 3885 #include <ddb/ddb.h> 3886 3887 DB_SHOW_COMMAND(page, vm_page_print_page_info) 3888 { 3889 db_printf("vm_cnt.v_free_count: %d\n", vm_cnt.v_free_count); 3890 db_printf("vm_cnt.v_cache_count: %d\n", vm_cnt.v_cache_count); 3891 db_printf("vm_cnt.v_inactive_count: %d\n", vm_cnt.v_inactive_count); 3892 db_printf("vm_cnt.v_active_count: %d\n", vm_cnt.v_active_count); 3893 db_printf("vm_cnt.v_wire_count: %d\n", vm_cnt.v_wire_count); 3894 db_printf("vm_cnt.v_free_reserved: %d\n", vm_cnt.v_free_reserved); 3895 db_printf("vm_cnt.v_free_min: %d\n", vm_cnt.v_free_min); 3896 db_printf("vm_cnt.v_free_target: %d\n", vm_cnt.v_free_target); 3897 db_printf("vm_cnt.v_inactive_target: %d\n", vm_cnt.v_inactive_target); 3898 } 3899 3900 DB_SHOW_COMMAND(pageq, vm_page_print_pageq_info) 3901 { 3902 int dom; 3903 3904 db_printf("pq_free %d pq_cache %d\n", 3905 vm_cnt.v_free_count, vm_cnt.v_cache_count); 3906 for (dom = 0; dom < vm_ndomains; dom++) { 3907 db_printf( 3908 "dom %d page_cnt %d free %d pq_act %d pq_inact %d pass %d\n", 3909 dom, 3910 vm_dom[dom].vmd_page_count, 3911 vm_dom[dom].vmd_free_count, 3912 vm_dom[dom].vmd_pagequeues[PQ_ACTIVE].pq_cnt, 3913 vm_dom[dom].vmd_pagequeues[PQ_INACTIVE].pq_cnt, 3914 vm_dom[dom].vmd_pass); 3915 } 3916 } 3917 3918 DB_SHOW_COMMAND(pginfo, vm_page_print_pginfo) 3919 { 3920 vm_page_t m; 3921 boolean_t phys; 3922 3923 if (!have_addr) { 3924 db_printf("show pginfo addr\n"); 3925 return; 3926 } 3927 3928 phys = strchr(modif, 'p') != NULL; 3929 if (phys) 3930 m = PHYS_TO_VM_PAGE(addr); 3931 else 3932 m = (vm_page_t)addr; 3933 db_printf( 3934 "page %p obj %p pidx 0x%jx phys 0x%jx q %d hold %d wire %d\n" 3935 " af 0x%x of 0x%x f 0x%x act %d busy %x valid 0x%x dirty 0x%x\n", 3936 m, m->object, (uintmax_t)m->pindex, (uintmax_t)m->phys_addr, 3937 m->queue, m->hold_count, m->wire_count, m->aflags, m->oflags, 3938 m->flags, m->act_count, m->busy_lock, m->valid, m->dirty); 3939 } 3940 #endif /* DDB */ 3941