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_locked(vm_page_t m) 764 { 765 766 vm_page_assert_xbusied(m); 767 vm_page_assert_locked(m); 768 769 atomic_store_rel_int(&m->busy_lock, VPB_UNBUSIED); 770 /* There is a waiter, do wakeup() instead of vm_page_flash(). */ 771 wakeup(m); 772 } 773 774 static void 775 vm_page_xunbusy_maybelocked(vm_page_t m) 776 { 777 bool lockacq; 778 779 vm_page_assert_xbusied(m); 780 781 /* 782 * Fast path for unbusy. If it succeeds, we know that there 783 * are no waiters, so we do not need a wakeup. 784 */ 785 if (atomic_cmpset_rel_int(&m->busy_lock, VPB_SINGLE_EXCLUSIVER, 786 VPB_UNBUSIED)) 787 return; 788 789 lockacq = !mtx_owned(vm_page_lockptr(m)); 790 if (lockacq) 791 vm_page_lock(m); 792 vm_page_xunbusy_locked(m); 793 if (lockacq) 794 vm_page_unlock(m); 795 } 796 797 /* 798 * vm_page_xunbusy_hard: 799 * 800 * Called after the first try the exclusive unbusy of a page failed. 801 * It is assumed that the waiters bit is on. 802 */ 803 void 804 vm_page_xunbusy_hard(vm_page_t m) 805 { 806 807 vm_page_assert_xbusied(m); 808 809 vm_page_lock(m); 810 vm_page_xunbusy_locked(m); 811 vm_page_unlock(m); 812 } 813 814 /* 815 * vm_page_flash: 816 * 817 * Wakeup anyone waiting for the page. 818 * The ownership bits do not change. 819 * 820 * The given page must be locked. 821 */ 822 void 823 vm_page_flash(vm_page_t m) 824 { 825 u_int x; 826 827 vm_page_lock_assert(m, MA_OWNED); 828 829 for (;;) { 830 x = m->busy_lock; 831 if ((x & VPB_BIT_WAITERS) == 0) 832 return; 833 if (atomic_cmpset_int(&m->busy_lock, x, 834 x & (~VPB_BIT_WAITERS))) 835 break; 836 } 837 wakeup(m); 838 } 839 840 /* 841 * Keep page from being freed by the page daemon 842 * much of the same effect as wiring, except much lower 843 * overhead and should be used only for *very* temporary 844 * holding ("wiring"). 845 */ 846 void 847 vm_page_hold(vm_page_t mem) 848 { 849 850 vm_page_lock_assert(mem, MA_OWNED); 851 mem->hold_count++; 852 } 853 854 void 855 vm_page_unhold(vm_page_t mem) 856 { 857 858 vm_page_lock_assert(mem, MA_OWNED); 859 KASSERT(mem->hold_count >= 1, ("vm_page_unhold: hold count < 0!!!")); 860 --mem->hold_count; 861 if (mem->hold_count == 0 && (mem->flags & PG_UNHOLDFREE) != 0) 862 vm_page_free_toq(mem); 863 } 864 865 /* 866 * vm_page_unhold_pages: 867 * 868 * Unhold each of the pages that is referenced by the given array. 869 */ 870 void 871 vm_page_unhold_pages(vm_page_t *ma, int count) 872 { 873 struct mtx *mtx, *new_mtx; 874 875 mtx = NULL; 876 for (; count != 0; count--) { 877 /* 878 * Avoid releasing and reacquiring the same page lock. 879 */ 880 new_mtx = vm_page_lockptr(*ma); 881 if (mtx != new_mtx) { 882 if (mtx != NULL) 883 mtx_unlock(mtx); 884 mtx = new_mtx; 885 mtx_lock(mtx); 886 } 887 vm_page_unhold(*ma); 888 ma++; 889 } 890 if (mtx != NULL) 891 mtx_unlock(mtx); 892 } 893 894 vm_page_t 895 PHYS_TO_VM_PAGE(vm_paddr_t pa) 896 { 897 vm_page_t m; 898 899 #ifdef VM_PHYSSEG_SPARSE 900 m = vm_phys_paddr_to_vm_page(pa); 901 if (m == NULL) 902 m = vm_phys_fictitious_to_vm_page(pa); 903 return (m); 904 #elif defined(VM_PHYSSEG_DENSE) 905 long pi; 906 907 pi = atop(pa); 908 if (pi >= first_page && (pi - first_page) < vm_page_array_size) { 909 m = &vm_page_array[pi - first_page]; 910 return (m); 911 } 912 return (vm_phys_fictitious_to_vm_page(pa)); 913 #else 914 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." 915 #endif 916 } 917 918 /* 919 * vm_page_getfake: 920 * 921 * Create a fictitious page with the specified physical address and 922 * memory attribute. The memory attribute is the only the machine- 923 * dependent aspect of a fictitious page that must be initialized. 924 */ 925 vm_page_t 926 vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr) 927 { 928 vm_page_t m; 929 930 m = uma_zalloc(fakepg_zone, M_WAITOK | M_ZERO); 931 vm_page_initfake(m, paddr, memattr); 932 return (m); 933 } 934 935 void 936 vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) 937 { 938 939 if ((m->flags & PG_FICTITIOUS) != 0) { 940 /* 941 * The page's memattr might have changed since the 942 * previous initialization. Update the pmap to the 943 * new memattr. 944 */ 945 goto memattr; 946 } 947 m->phys_addr = paddr; 948 m->queue = PQ_NONE; 949 /* Fictitious pages don't use "segind". */ 950 m->flags = PG_FICTITIOUS; 951 /* Fictitious pages don't use "order" or "pool". */ 952 m->oflags = VPO_UNMANAGED; 953 m->busy_lock = VPB_SINGLE_EXCLUSIVER; 954 m->wire_count = 1; 955 pmap_page_init(m); 956 memattr: 957 pmap_page_set_memattr(m, memattr); 958 } 959 960 /* 961 * vm_page_putfake: 962 * 963 * Release a fictitious page. 964 */ 965 void 966 vm_page_putfake(vm_page_t m) 967 { 968 969 KASSERT((m->oflags & VPO_UNMANAGED) != 0, ("managed %p", m)); 970 KASSERT((m->flags & PG_FICTITIOUS) != 0, 971 ("vm_page_putfake: bad page %p", m)); 972 uma_zfree(fakepg_zone, m); 973 } 974 975 /* 976 * vm_page_updatefake: 977 * 978 * Update the given fictitious page to the specified physical address and 979 * memory attribute. 980 */ 981 void 982 vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) 983 { 984 985 KASSERT((m->flags & PG_FICTITIOUS) != 0, 986 ("vm_page_updatefake: bad page %p", m)); 987 m->phys_addr = paddr; 988 pmap_page_set_memattr(m, memattr); 989 } 990 991 /* 992 * vm_page_free: 993 * 994 * Free a page. 995 */ 996 void 997 vm_page_free(vm_page_t m) 998 { 999 1000 m->flags &= ~PG_ZERO; 1001 vm_page_free_toq(m); 1002 } 1003 1004 /* 1005 * vm_page_free_zero: 1006 * 1007 * Free a page to the zerod-pages queue 1008 */ 1009 void 1010 vm_page_free_zero(vm_page_t m) 1011 { 1012 1013 m->flags |= PG_ZERO; 1014 vm_page_free_toq(m); 1015 } 1016 1017 /* 1018 * Unbusy and handle the page queueing for a page from the VOP_GETPAGES() 1019 * array which was optionally read ahead or behind. 1020 */ 1021 void 1022 vm_page_readahead_finish(vm_page_t m) 1023 { 1024 1025 /* We shouldn't put invalid pages on queues. */ 1026 KASSERT(m->valid != 0, ("%s: %p is invalid", __func__, m)); 1027 1028 /* 1029 * Since the page is not the actually needed one, whether it should 1030 * be activated or deactivated is not obvious. Empirical results 1031 * have shown that deactivating the page is usually the best choice, 1032 * unless the page is wanted by another thread. 1033 */ 1034 vm_page_lock(m); 1035 if ((m->busy_lock & VPB_BIT_WAITERS) != 0) 1036 vm_page_activate(m); 1037 else 1038 vm_page_deactivate(m); 1039 vm_page_unlock(m); 1040 vm_page_xunbusy(m); 1041 } 1042 1043 /* 1044 * vm_page_sleep_if_busy: 1045 * 1046 * Sleep and release the page queues lock if the page is busied. 1047 * Returns TRUE if the thread slept. 1048 * 1049 * The given page must be unlocked and object containing it must 1050 * be locked. 1051 */ 1052 int 1053 vm_page_sleep_if_busy(vm_page_t m, const char *msg) 1054 { 1055 vm_object_t obj; 1056 1057 vm_page_lock_assert(m, MA_NOTOWNED); 1058 VM_OBJECT_ASSERT_WLOCKED(m->object); 1059 1060 if (vm_page_busied(m)) { 1061 /* 1062 * The page-specific object must be cached because page 1063 * identity can change during the sleep, causing the 1064 * re-lock of a different object. 1065 * It is assumed that a reference to the object is already 1066 * held by the callers. 1067 */ 1068 obj = m->object; 1069 vm_page_lock(m); 1070 VM_OBJECT_WUNLOCK(obj); 1071 vm_page_busy_sleep(m, msg); 1072 VM_OBJECT_WLOCK(obj); 1073 return (TRUE); 1074 } 1075 return (FALSE); 1076 } 1077 1078 /* 1079 * vm_page_dirty_KBI: [ internal use only ] 1080 * 1081 * Set all bits in the page's dirty field. 1082 * 1083 * The object containing the specified page must be locked if the 1084 * call is made from the machine-independent layer. 1085 * 1086 * See vm_page_clear_dirty_mask(). 1087 * 1088 * This function should only be called by vm_page_dirty(). 1089 */ 1090 void 1091 vm_page_dirty_KBI(vm_page_t m) 1092 { 1093 1094 /* These assertions refer to this operation by its public name. */ 1095 KASSERT((m->flags & PG_CACHED) == 0, 1096 ("vm_page_dirty: page in cache!")); 1097 KASSERT(m->valid == VM_PAGE_BITS_ALL, 1098 ("vm_page_dirty: page is invalid!")); 1099 m->dirty = VM_PAGE_BITS_ALL; 1100 } 1101 1102 /* 1103 * vm_page_insert: [ internal use only ] 1104 * 1105 * Inserts the given mem entry into the object and object list. 1106 * 1107 * The object must be locked. 1108 */ 1109 int 1110 vm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex) 1111 { 1112 vm_page_t mpred; 1113 1114 VM_OBJECT_ASSERT_WLOCKED(object); 1115 mpred = vm_radix_lookup_le(&object->rtree, pindex); 1116 return (vm_page_insert_after(m, object, pindex, mpred)); 1117 } 1118 1119 /* 1120 * vm_page_insert_after: 1121 * 1122 * Inserts the page "m" into the specified object at offset "pindex". 1123 * 1124 * The page "mpred" must immediately precede the offset "pindex" within 1125 * the specified object. 1126 * 1127 * The object must be locked. 1128 */ 1129 static int 1130 vm_page_insert_after(vm_page_t m, vm_object_t object, vm_pindex_t pindex, 1131 vm_page_t mpred) 1132 { 1133 vm_page_t msucc; 1134 1135 VM_OBJECT_ASSERT_WLOCKED(object); 1136 KASSERT(m->object == NULL, 1137 ("vm_page_insert_after: page already inserted")); 1138 if (mpred != NULL) { 1139 KASSERT(mpred->object == object, 1140 ("vm_page_insert_after: object doesn't contain mpred")); 1141 KASSERT(mpred->pindex < pindex, 1142 ("vm_page_insert_after: mpred doesn't precede pindex")); 1143 msucc = TAILQ_NEXT(mpred, listq); 1144 } else 1145 msucc = TAILQ_FIRST(&object->memq); 1146 if (msucc != NULL) 1147 KASSERT(msucc->pindex > pindex, 1148 ("vm_page_insert_after: msucc doesn't succeed pindex")); 1149 1150 /* 1151 * Record the object/offset pair in this page 1152 */ 1153 m->object = object; 1154 m->pindex = pindex; 1155 1156 /* 1157 * Now link into the object's ordered list of backed pages. 1158 */ 1159 if (vm_radix_insert(&object->rtree, m)) { 1160 m->object = NULL; 1161 m->pindex = 0; 1162 return (1); 1163 } 1164 vm_page_insert_radixdone(m, object, mpred); 1165 return (0); 1166 } 1167 1168 /* 1169 * vm_page_insert_radixdone: 1170 * 1171 * Complete page "m" insertion into the specified object after the 1172 * radix trie hooking. 1173 * 1174 * The page "mpred" must precede the offset "m->pindex" within the 1175 * specified object. 1176 * 1177 * The object must be locked. 1178 */ 1179 static void 1180 vm_page_insert_radixdone(vm_page_t m, vm_object_t object, vm_page_t mpred) 1181 { 1182 1183 VM_OBJECT_ASSERT_WLOCKED(object); 1184 KASSERT(object != NULL && m->object == object, 1185 ("vm_page_insert_radixdone: page %p has inconsistent object", m)); 1186 if (mpred != NULL) { 1187 KASSERT(mpred->object == object, 1188 ("vm_page_insert_after: object doesn't contain mpred")); 1189 KASSERT(mpred->pindex < m->pindex, 1190 ("vm_page_insert_after: mpred doesn't precede pindex")); 1191 } 1192 1193 if (mpred != NULL) 1194 TAILQ_INSERT_AFTER(&object->memq, mpred, m, listq); 1195 else 1196 TAILQ_INSERT_HEAD(&object->memq, m, listq); 1197 1198 /* 1199 * Show that the object has one more resident page. 1200 */ 1201 object->resident_page_count++; 1202 1203 /* 1204 * Hold the vnode until the last page is released. 1205 */ 1206 if (object->resident_page_count == 1 && object->type == OBJT_VNODE) 1207 vhold(object->handle); 1208 1209 /* 1210 * Since we are inserting a new and possibly dirty page, 1211 * update the object's OBJ_MIGHTBEDIRTY flag. 1212 */ 1213 if (pmap_page_is_write_mapped(m)) 1214 vm_object_set_writeable_dirty(object); 1215 } 1216 1217 /* 1218 * vm_page_remove: 1219 * 1220 * Removes the given mem entry from the object/offset-page 1221 * table and the object page list, but do not invalidate/terminate 1222 * the backing store. 1223 * 1224 * The object must be locked. The page must be locked if it is managed. 1225 */ 1226 void 1227 vm_page_remove(vm_page_t m) 1228 { 1229 vm_object_t object; 1230 1231 if ((m->oflags & VPO_UNMANAGED) == 0) 1232 vm_page_assert_locked(m); 1233 if ((object = m->object) == NULL) 1234 return; 1235 VM_OBJECT_ASSERT_WLOCKED(object); 1236 if (vm_page_xbusied(m)) 1237 vm_page_xunbusy_maybelocked(m); 1238 1239 /* 1240 * Now remove from the object's list of backed pages. 1241 */ 1242 vm_radix_remove(&object->rtree, m->pindex); 1243 TAILQ_REMOVE(&object->memq, m, listq); 1244 1245 /* 1246 * And show that the object has one fewer resident page. 1247 */ 1248 object->resident_page_count--; 1249 1250 /* 1251 * The vnode may now be recycled. 1252 */ 1253 if (object->resident_page_count == 0 && object->type == OBJT_VNODE) 1254 vdrop(object->handle); 1255 1256 m->object = NULL; 1257 } 1258 1259 /* 1260 * vm_page_lookup: 1261 * 1262 * Returns the page associated with the object/offset 1263 * pair specified; if none is found, NULL is returned. 1264 * 1265 * The object must be locked. 1266 */ 1267 vm_page_t 1268 vm_page_lookup(vm_object_t object, vm_pindex_t pindex) 1269 { 1270 1271 VM_OBJECT_ASSERT_LOCKED(object); 1272 return (vm_radix_lookup(&object->rtree, pindex)); 1273 } 1274 1275 /* 1276 * vm_page_find_least: 1277 * 1278 * Returns the page associated with the object with least pindex 1279 * greater than or equal to the parameter pindex, or NULL. 1280 * 1281 * The object must be locked. 1282 */ 1283 vm_page_t 1284 vm_page_find_least(vm_object_t object, vm_pindex_t pindex) 1285 { 1286 vm_page_t m; 1287 1288 VM_OBJECT_ASSERT_LOCKED(object); 1289 if ((m = TAILQ_FIRST(&object->memq)) != NULL && m->pindex < pindex) 1290 m = vm_radix_lookup_ge(&object->rtree, pindex); 1291 return (m); 1292 } 1293 1294 /* 1295 * Returns the given page's successor (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_next(vm_page_t m) 1302 { 1303 vm_page_t next; 1304 1305 VM_OBJECT_ASSERT_LOCKED(m->object); 1306 if ((next = TAILQ_NEXT(m, listq)) != NULL && 1307 next->pindex != m->pindex + 1) 1308 next = NULL; 1309 return (next); 1310 } 1311 1312 /* 1313 * Returns the given page's predecessor (by pindex) within the object if it is 1314 * resident; if none is found, NULL is returned. 1315 * 1316 * The object must be locked. 1317 */ 1318 vm_page_t 1319 vm_page_prev(vm_page_t m) 1320 { 1321 vm_page_t prev; 1322 1323 VM_OBJECT_ASSERT_LOCKED(m->object); 1324 if ((prev = TAILQ_PREV(m, pglist, listq)) != NULL && 1325 prev->pindex != m->pindex - 1) 1326 prev = NULL; 1327 return (prev); 1328 } 1329 1330 /* 1331 * Uses the page mnew as a replacement for an existing page at index 1332 * pindex which must be already present in the object. 1333 * 1334 * The existing page must not be on a paging queue. 1335 */ 1336 vm_page_t 1337 vm_page_replace(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex) 1338 { 1339 vm_page_t mold; 1340 1341 VM_OBJECT_ASSERT_WLOCKED(object); 1342 KASSERT(mnew->object == NULL, 1343 ("vm_page_replace: page already in object")); 1344 1345 /* 1346 * This function mostly follows vm_page_insert() and 1347 * vm_page_remove() without the radix, object count and vnode 1348 * dance. Double check such functions for more comments. 1349 */ 1350 1351 mnew->object = object; 1352 mnew->pindex = pindex; 1353 mold = vm_radix_replace(&object->rtree, mnew); 1354 KASSERT(mold->queue == PQ_NONE, 1355 ("vm_page_replace: mold is on a paging queue")); 1356 1357 /* Keep the resident page list in sorted order. */ 1358 TAILQ_INSERT_AFTER(&object->memq, mold, mnew, listq); 1359 TAILQ_REMOVE(&object->memq, mold, listq); 1360 1361 mold->object = NULL; 1362 vm_page_xunbusy_maybelocked(mold); 1363 1364 /* 1365 * The object's resident_page_count does not change because we have 1366 * swapped one page for another, but OBJ_MIGHTBEDIRTY. 1367 */ 1368 if (pmap_page_is_write_mapped(mnew)) 1369 vm_object_set_writeable_dirty(object); 1370 return (mold); 1371 } 1372 1373 /* 1374 * vm_page_rename: 1375 * 1376 * Move the given memory entry from its 1377 * current object to the specified target object/offset. 1378 * 1379 * Note: swap associated with the page must be invalidated by the move. We 1380 * have to do this for several reasons: (1) we aren't freeing the 1381 * page, (2) we are dirtying the page, (3) the VM system is probably 1382 * moving the page from object A to B, and will then later move 1383 * the backing store from A to B and we can't have a conflict. 1384 * 1385 * Note: we *always* dirty the page. It is necessary both for the 1386 * fact that we moved it, and because we may be invalidating 1387 * swap. If the page is on the cache, we have to deactivate it 1388 * or vm_page_dirty() will panic. Dirty pages are not allowed 1389 * on the cache. 1390 * 1391 * The objects must be locked. 1392 */ 1393 int 1394 vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex) 1395 { 1396 vm_page_t mpred; 1397 vm_pindex_t opidx; 1398 1399 VM_OBJECT_ASSERT_WLOCKED(new_object); 1400 1401 mpred = vm_radix_lookup_le(&new_object->rtree, new_pindex); 1402 KASSERT(mpred == NULL || mpred->pindex != new_pindex, 1403 ("vm_page_rename: pindex already renamed")); 1404 1405 /* 1406 * Create a custom version of vm_page_insert() which does not depend 1407 * by m_prev and can cheat on the implementation aspects of the 1408 * function. 1409 */ 1410 opidx = m->pindex; 1411 m->pindex = new_pindex; 1412 if (vm_radix_insert(&new_object->rtree, m)) { 1413 m->pindex = opidx; 1414 return (1); 1415 } 1416 1417 /* 1418 * The operation cannot fail anymore. The removal must happen before 1419 * the listq iterator is tainted. 1420 */ 1421 m->pindex = opidx; 1422 vm_page_lock(m); 1423 vm_page_remove(m); 1424 1425 /* Return back to the new pindex to complete vm_page_insert(). */ 1426 m->pindex = new_pindex; 1427 m->object = new_object; 1428 vm_page_unlock(m); 1429 vm_page_insert_radixdone(m, new_object, mpred); 1430 vm_page_dirty(m); 1431 return (0); 1432 } 1433 1434 /* 1435 * Convert all of the given object's cached pages that have a 1436 * pindex within the given range into free pages. If the value 1437 * zero is given for "end", then the range's upper bound is 1438 * infinity. If the given object is backed by a vnode and it 1439 * transitions from having one or more cached pages to none, the 1440 * vnode's hold count is reduced. 1441 */ 1442 void 1443 vm_page_cache_free(vm_object_t object, vm_pindex_t start, vm_pindex_t end) 1444 { 1445 vm_page_t m; 1446 boolean_t empty; 1447 1448 mtx_lock(&vm_page_queue_free_mtx); 1449 if (__predict_false(vm_radix_is_empty(&object->cache))) { 1450 mtx_unlock(&vm_page_queue_free_mtx); 1451 return; 1452 } 1453 while ((m = vm_radix_lookup_ge(&object->cache, start)) != NULL) { 1454 if (end != 0 && m->pindex >= end) 1455 break; 1456 vm_radix_remove(&object->cache, m->pindex); 1457 vm_page_cache_turn_free(m); 1458 } 1459 empty = vm_radix_is_empty(&object->cache); 1460 mtx_unlock(&vm_page_queue_free_mtx); 1461 if (object->type == OBJT_VNODE && empty) 1462 vdrop(object->handle); 1463 } 1464 1465 /* 1466 * Returns the cached page that is associated with the given 1467 * object and offset. If, however, none exists, returns NULL. 1468 * 1469 * The free page queue must be locked. 1470 */ 1471 static inline vm_page_t 1472 vm_page_cache_lookup(vm_object_t object, vm_pindex_t pindex) 1473 { 1474 1475 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 1476 return (vm_radix_lookup(&object->cache, pindex)); 1477 } 1478 1479 /* 1480 * Remove the given cached page from its containing object's 1481 * collection of cached pages. 1482 * 1483 * The free page queue must be locked. 1484 */ 1485 static void 1486 vm_page_cache_remove(vm_page_t m) 1487 { 1488 1489 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 1490 KASSERT((m->flags & PG_CACHED) != 0, 1491 ("vm_page_cache_remove: page %p is not cached", m)); 1492 vm_radix_remove(&m->object->cache, m->pindex); 1493 m->object = NULL; 1494 vm_cnt.v_cache_count--; 1495 } 1496 1497 /* 1498 * Transfer all of the cached pages with offset greater than or 1499 * equal to 'offidxstart' from the original object's cache to the 1500 * new object's cache. However, any cached pages with offset 1501 * greater than or equal to the new object's size are kept in the 1502 * original object. Initially, the new object's cache must be 1503 * empty. Offset 'offidxstart' in the original object must 1504 * correspond to offset zero in the new object. 1505 * 1506 * The new object must be locked. 1507 */ 1508 void 1509 vm_page_cache_transfer(vm_object_t orig_object, vm_pindex_t offidxstart, 1510 vm_object_t new_object) 1511 { 1512 vm_page_t m; 1513 1514 /* 1515 * Insertion into an object's collection of cached pages 1516 * requires the object to be locked. In contrast, removal does 1517 * not. 1518 */ 1519 VM_OBJECT_ASSERT_WLOCKED(new_object); 1520 KASSERT(vm_radix_is_empty(&new_object->cache), 1521 ("vm_page_cache_transfer: object %p has cached pages", 1522 new_object)); 1523 mtx_lock(&vm_page_queue_free_mtx); 1524 while ((m = vm_radix_lookup_ge(&orig_object->cache, 1525 offidxstart)) != NULL) { 1526 /* 1527 * Transfer all of the pages with offset greater than or 1528 * equal to 'offidxstart' from the original object's 1529 * cache to the new object's cache. 1530 */ 1531 if ((m->pindex - offidxstart) >= new_object->size) 1532 break; 1533 vm_radix_remove(&orig_object->cache, m->pindex); 1534 /* Update the page's object and offset. */ 1535 m->object = new_object; 1536 m->pindex -= offidxstart; 1537 if (vm_radix_insert(&new_object->cache, m)) 1538 vm_page_cache_turn_free(m); 1539 } 1540 mtx_unlock(&vm_page_queue_free_mtx); 1541 } 1542 1543 /* 1544 * Returns TRUE if a cached page is associated with the given object and 1545 * offset, and FALSE otherwise. 1546 * 1547 * The object must be locked. 1548 */ 1549 boolean_t 1550 vm_page_is_cached(vm_object_t object, vm_pindex_t pindex) 1551 { 1552 vm_page_t m; 1553 1554 /* 1555 * Insertion into an object's collection of cached pages requires the 1556 * object to be locked. Therefore, if the object is locked and the 1557 * object's collection is empty, there is no need to acquire the free 1558 * page queues lock in order to prove that the specified page doesn't 1559 * exist. 1560 */ 1561 VM_OBJECT_ASSERT_WLOCKED(object); 1562 if (__predict_true(vm_object_cache_is_empty(object))) 1563 return (FALSE); 1564 mtx_lock(&vm_page_queue_free_mtx); 1565 m = vm_page_cache_lookup(object, pindex); 1566 mtx_unlock(&vm_page_queue_free_mtx); 1567 return (m != NULL); 1568 } 1569 1570 /* 1571 * vm_page_alloc: 1572 * 1573 * Allocate and return a page that is associated with the specified 1574 * object and offset pair. By default, this page is exclusive busied. 1575 * 1576 * The caller must always specify an allocation class. 1577 * 1578 * allocation classes: 1579 * VM_ALLOC_NORMAL normal process request 1580 * VM_ALLOC_SYSTEM system *really* needs a page 1581 * VM_ALLOC_INTERRUPT interrupt time request 1582 * 1583 * optional allocation flags: 1584 * VM_ALLOC_COUNT(number) the number of additional pages that the caller 1585 * intends to allocate 1586 * VM_ALLOC_IFCACHED return page only if it is cached 1587 * VM_ALLOC_IFNOTCACHED return NULL, do not reactivate if the page 1588 * is cached 1589 * VM_ALLOC_NOBUSY do not exclusive busy the page 1590 * VM_ALLOC_NODUMP do not include the page in a kernel core dump 1591 * VM_ALLOC_NOOBJ page is not associated with an object and 1592 * should not be exclusive busy 1593 * VM_ALLOC_SBUSY shared busy the allocated page 1594 * VM_ALLOC_WIRED wire the allocated page 1595 * VM_ALLOC_ZERO prefer a zeroed page 1596 * 1597 * This routine may not sleep. 1598 */ 1599 vm_page_t 1600 vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req) 1601 { 1602 struct vnode *vp = NULL; 1603 vm_object_t m_object; 1604 vm_page_t m, mpred; 1605 int flags, req_class; 1606 1607 mpred = 0; /* XXX: pacify gcc */ 1608 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) && 1609 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) && 1610 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 1611 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 1612 ("vm_page_alloc: inconsistent object(%p)/req(%x)", (void *)object, 1613 req)); 1614 if (object != NULL) 1615 VM_OBJECT_ASSERT_WLOCKED(object); 1616 1617 req_class = req & VM_ALLOC_CLASS_MASK; 1618 1619 /* 1620 * The page daemon is allowed to dig deeper into the free page list. 1621 */ 1622 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 1623 req_class = VM_ALLOC_SYSTEM; 1624 1625 if (object != NULL) { 1626 mpred = vm_radix_lookup_le(&object->rtree, pindex); 1627 KASSERT(mpred == NULL || mpred->pindex != pindex, 1628 ("vm_page_alloc: pindex already allocated")); 1629 } 1630 1631 /* 1632 * The page allocation request can came from consumers which already 1633 * hold the free page queue mutex, like vm_page_insert() in 1634 * vm_page_cache(). 1635 */ 1636 mtx_lock_flags(&vm_page_queue_free_mtx, MTX_RECURSE); 1637 if (vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_free_reserved || 1638 (req_class == VM_ALLOC_SYSTEM && 1639 vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_interrupt_free_min) || 1640 (req_class == VM_ALLOC_INTERRUPT && 1641 vm_cnt.v_free_count + vm_cnt.v_cache_count > 0)) { 1642 /* 1643 * Allocate from the free queue if the number of free pages 1644 * exceeds the minimum for the request class. 1645 */ 1646 if (object != NULL && 1647 (m = vm_page_cache_lookup(object, pindex)) != NULL) { 1648 if ((req & VM_ALLOC_IFNOTCACHED) != 0) { 1649 mtx_unlock(&vm_page_queue_free_mtx); 1650 return (NULL); 1651 } 1652 if (vm_phys_unfree_page(m)) 1653 vm_phys_set_pool(VM_FREEPOOL_DEFAULT, m, 0); 1654 #if VM_NRESERVLEVEL > 0 1655 else if (!vm_reserv_reactivate_page(m)) 1656 #else 1657 else 1658 #endif 1659 panic("vm_page_alloc: cache page %p is missing" 1660 " from the free queue", m); 1661 } else if ((req & VM_ALLOC_IFCACHED) != 0) { 1662 mtx_unlock(&vm_page_queue_free_mtx); 1663 return (NULL); 1664 #if VM_NRESERVLEVEL > 0 1665 } else if (object == NULL || (object->flags & (OBJ_COLORED | 1666 OBJ_FICTITIOUS)) != OBJ_COLORED || (m = 1667 vm_reserv_alloc_page(object, pindex, mpred)) == NULL) { 1668 #else 1669 } else { 1670 #endif 1671 m = vm_phys_alloc_pages(object != NULL ? 1672 VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT, 0); 1673 #if VM_NRESERVLEVEL > 0 1674 if (m == NULL && vm_reserv_reclaim_inactive()) { 1675 m = vm_phys_alloc_pages(object != NULL ? 1676 VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT, 1677 0); 1678 } 1679 #endif 1680 } 1681 } else { 1682 /* 1683 * Not allocatable, give up. 1684 */ 1685 mtx_unlock(&vm_page_queue_free_mtx); 1686 atomic_add_int(&vm_pageout_deficit, 1687 max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1)); 1688 pagedaemon_wakeup(); 1689 return (NULL); 1690 } 1691 1692 /* 1693 * At this point we had better have found a good page. 1694 */ 1695 KASSERT(m != NULL, ("vm_page_alloc: missing page")); 1696 KASSERT(m->queue == PQ_NONE, 1697 ("vm_page_alloc: page %p has unexpected queue %d", m, m->queue)); 1698 KASSERT(m->wire_count == 0, ("vm_page_alloc: page %p is wired", m)); 1699 KASSERT(m->hold_count == 0, ("vm_page_alloc: page %p is held", m)); 1700 KASSERT(!vm_page_sbusied(m), 1701 ("vm_page_alloc: page %p is busy", m)); 1702 KASSERT(m->dirty == 0, ("vm_page_alloc: page %p is dirty", m)); 1703 KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, 1704 ("vm_page_alloc: page %p has unexpected memattr %d", m, 1705 pmap_page_get_memattr(m))); 1706 if ((m->flags & PG_CACHED) != 0) { 1707 KASSERT((m->flags & PG_ZERO) == 0, 1708 ("vm_page_alloc: cached page %p is PG_ZERO", m)); 1709 KASSERT(m->valid != 0, 1710 ("vm_page_alloc: cached page %p is invalid", m)); 1711 if (m->object == object && m->pindex == pindex) 1712 vm_cnt.v_reactivated++; 1713 else 1714 m->valid = 0; 1715 m_object = m->object; 1716 vm_page_cache_remove(m); 1717 if (m_object->type == OBJT_VNODE && 1718 vm_object_cache_is_empty(m_object)) 1719 vp = m_object->handle; 1720 } else { 1721 KASSERT(m->valid == 0, 1722 ("vm_page_alloc: free page %p is valid", m)); 1723 vm_phys_freecnt_adj(m, -1); 1724 if ((m->flags & PG_ZERO) != 0) 1725 vm_page_zero_count--; 1726 } 1727 mtx_unlock(&vm_page_queue_free_mtx); 1728 1729 /* 1730 * Initialize the page. Only the PG_ZERO flag is inherited. 1731 */ 1732 flags = 0; 1733 if ((req & VM_ALLOC_ZERO) != 0) 1734 flags = PG_ZERO; 1735 flags &= m->flags; 1736 if ((req & VM_ALLOC_NODUMP) != 0) 1737 flags |= PG_NODUMP; 1738 m->flags = flags; 1739 m->aflags = 0; 1740 m->oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ? 1741 VPO_UNMANAGED : 0; 1742 m->busy_lock = VPB_UNBUSIED; 1743 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0) 1744 m->busy_lock = VPB_SINGLE_EXCLUSIVER; 1745 if ((req & VM_ALLOC_SBUSY) != 0) 1746 m->busy_lock = VPB_SHARERS_WORD(1); 1747 if (req & VM_ALLOC_WIRED) { 1748 /* 1749 * The page lock is not required for wiring a page until that 1750 * page is inserted into the object. 1751 */ 1752 atomic_add_int(&vm_cnt.v_wire_count, 1); 1753 m->wire_count = 1; 1754 } 1755 m->act_count = 0; 1756 1757 if (object != NULL) { 1758 if (vm_page_insert_after(m, object, pindex, mpred)) { 1759 /* See the comment below about hold count. */ 1760 if (vp != NULL) 1761 vdrop(vp); 1762 pagedaemon_wakeup(); 1763 if (req & VM_ALLOC_WIRED) { 1764 atomic_subtract_int(&vm_cnt.v_wire_count, 1); 1765 m->wire_count = 0; 1766 } 1767 m->object = NULL; 1768 m->oflags = VPO_UNMANAGED; 1769 m->busy_lock = VPB_UNBUSIED; 1770 vm_page_free(m); 1771 return (NULL); 1772 } 1773 1774 /* Ignore device objects; the pager sets "memattr" for them. */ 1775 if (object->memattr != VM_MEMATTR_DEFAULT && 1776 (object->flags & OBJ_FICTITIOUS) == 0) 1777 pmap_page_set_memattr(m, object->memattr); 1778 } else 1779 m->pindex = pindex; 1780 1781 /* 1782 * The following call to vdrop() must come after the above call 1783 * to vm_page_insert() in case both affect the same object and 1784 * vnode. Otherwise, the affected vnode's hold count could 1785 * temporarily become zero. 1786 */ 1787 if (vp != NULL) 1788 vdrop(vp); 1789 1790 /* 1791 * Don't wakeup too often - wakeup the pageout daemon when 1792 * we would be nearly out of memory. 1793 */ 1794 if (vm_paging_needed()) 1795 pagedaemon_wakeup(); 1796 1797 return (m); 1798 } 1799 1800 static void 1801 vm_page_alloc_contig_vdrop(struct spglist *lst) 1802 { 1803 1804 while (!SLIST_EMPTY(lst)) { 1805 vdrop((struct vnode *)SLIST_FIRST(lst)-> plinks.s.pv); 1806 SLIST_REMOVE_HEAD(lst, plinks.s.ss); 1807 } 1808 } 1809 1810 /* 1811 * vm_page_alloc_contig: 1812 * 1813 * Allocate a contiguous set of physical pages of the given size "npages" 1814 * from the free lists. All of the physical pages must be at or above 1815 * the given physical address "low" and below the given physical address 1816 * "high". The given value "alignment" determines the alignment of the 1817 * first physical page in the set. If the given value "boundary" is 1818 * non-zero, then the set of physical pages cannot cross any physical 1819 * address boundary that is a multiple of that value. Both "alignment" 1820 * and "boundary" must be a power of two. 1821 * 1822 * If the specified memory attribute, "memattr", is VM_MEMATTR_DEFAULT, 1823 * then the memory attribute setting for the physical pages is configured 1824 * to the object's memory attribute setting. Otherwise, the memory 1825 * attribute setting for the physical pages is configured to "memattr", 1826 * overriding the object's memory attribute setting. However, if the 1827 * object's memory attribute setting is not VM_MEMATTR_DEFAULT, then the 1828 * memory attribute setting for the physical pages cannot be configured 1829 * to VM_MEMATTR_DEFAULT. 1830 * 1831 * The caller must always specify an allocation class. 1832 * 1833 * allocation classes: 1834 * VM_ALLOC_NORMAL normal process request 1835 * VM_ALLOC_SYSTEM system *really* needs a page 1836 * VM_ALLOC_INTERRUPT interrupt time request 1837 * 1838 * optional allocation flags: 1839 * VM_ALLOC_NOBUSY do not exclusive busy the page 1840 * VM_ALLOC_NODUMP do not include the page in a kernel core dump 1841 * VM_ALLOC_NOOBJ page is not associated with an object and 1842 * should not be exclusive busy 1843 * VM_ALLOC_SBUSY shared busy the allocated page 1844 * VM_ALLOC_WIRED wire the allocated page 1845 * VM_ALLOC_ZERO prefer a zeroed page 1846 * 1847 * This routine may not sleep. 1848 */ 1849 vm_page_t 1850 vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req, 1851 u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, 1852 vm_paddr_t boundary, vm_memattr_t memattr) 1853 { 1854 struct vnode *drop; 1855 struct spglist deferred_vdrop_list; 1856 vm_page_t m, m_tmp, m_ret; 1857 u_int flags; 1858 int req_class; 1859 1860 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) && 1861 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) && 1862 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 1863 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 1864 ("vm_page_alloc: inconsistent object(%p)/req(%x)", (void *)object, 1865 req)); 1866 if (object != NULL) { 1867 VM_OBJECT_ASSERT_WLOCKED(object); 1868 KASSERT(object->type == OBJT_PHYS, 1869 ("vm_page_alloc_contig: object %p isn't OBJT_PHYS", 1870 object)); 1871 } 1872 KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero")); 1873 req_class = req & VM_ALLOC_CLASS_MASK; 1874 1875 /* 1876 * The page daemon is allowed to dig deeper into the free page list. 1877 */ 1878 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 1879 req_class = VM_ALLOC_SYSTEM; 1880 1881 SLIST_INIT(&deferred_vdrop_list); 1882 mtx_lock(&vm_page_queue_free_mtx); 1883 if (vm_cnt.v_free_count + vm_cnt.v_cache_count >= npages + 1884 vm_cnt.v_free_reserved || (req_class == VM_ALLOC_SYSTEM && 1885 vm_cnt.v_free_count + vm_cnt.v_cache_count >= npages + 1886 vm_cnt.v_interrupt_free_min) || (req_class == VM_ALLOC_INTERRUPT && 1887 vm_cnt.v_free_count + vm_cnt.v_cache_count >= npages)) { 1888 #if VM_NRESERVLEVEL > 0 1889 retry: 1890 if (object == NULL || (object->flags & OBJ_COLORED) == 0 || 1891 (m_ret = vm_reserv_alloc_contig(object, pindex, npages, 1892 low, high, alignment, boundary)) == NULL) 1893 #endif 1894 m_ret = vm_phys_alloc_contig(npages, low, high, 1895 alignment, boundary); 1896 } else { 1897 mtx_unlock(&vm_page_queue_free_mtx); 1898 atomic_add_int(&vm_pageout_deficit, npages); 1899 pagedaemon_wakeup(); 1900 return (NULL); 1901 } 1902 if (m_ret != NULL) 1903 for (m = m_ret; m < &m_ret[npages]; m++) { 1904 drop = vm_page_alloc_init(m); 1905 if (drop != NULL) { 1906 /* 1907 * Enqueue the vnode for deferred vdrop(). 1908 */ 1909 m->plinks.s.pv = drop; 1910 SLIST_INSERT_HEAD(&deferred_vdrop_list, m, 1911 plinks.s.ss); 1912 } 1913 } 1914 else { 1915 #if VM_NRESERVLEVEL > 0 1916 if (vm_reserv_reclaim_contig(npages, low, high, alignment, 1917 boundary)) 1918 goto retry; 1919 #endif 1920 } 1921 mtx_unlock(&vm_page_queue_free_mtx); 1922 if (m_ret == NULL) 1923 return (NULL); 1924 1925 /* 1926 * Initialize the pages. Only the PG_ZERO flag is inherited. 1927 */ 1928 flags = 0; 1929 if ((req & VM_ALLOC_ZERO) != 0) 1930 flags = PG_ZERO; 1931 if ((req & VM_ALLOC_NODUMP) != 0) 1932 flags |= PG_NODUMP; 1933 if ((req & VM_ALLOC_WIRED) != 0) 1934 atomic_add_int(&vm_cnt.v_wire_count, npages); 1935 if (object != NULL) { 1936 if (object->memattr != VM_MEMATTR_DEFAULT && 1937 memattr == VM_MEMATTR_DEFAULT) 1938 memattr = object->memattr; 1939 } 1940 for (m = m_ret; m < &m_ret[npages]; m++) { 1941 m->aflags = 0; 1942 m->flags = (m->flags | PG_NODUMP) & flags; 1943 m->busy_lock = VPB_UNBUSIED; 1944 if (object != NULL) { 1945 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0) 1946 m->busy_lock = VPB_SINGLE_EXCLUSIVER; 1947 if ((req & VM_ALLOC_SBUSY) != 0) 1948 m->busy_lock = VPB_SHARERS_WORD(1); 1949 } 1950 if ((req & VM_ALLOC_WIRED) != 0) 1951 m->wire_count = 1; 1952 /* Unmanaged pages don't use "act_count". */ 1953 m->oflags = VPO_UNMANAGED; 1954 if (object != NULL) { 1955 if (vm_page_insert(m, object, pindex)) { 1956 vm_page_alloc_contig_vdrop( 1957 &deferred_vdrop_list); 1958 if (vm_paging_needed()) 1959 pagedaemon_wakeup(); 1960 if ((req & VM_ALLOC_WIRED) != 0) 1961 atomic_subtract_int(&vm_cnt.v_wire_count, 1962 npages); 1963 for (m_tmp = m, m = m_ret; 1964 m < &m_ret[npages]; m++) { 1965 if ((req & VM_ALLOC_WIRED) != 0) 1966 m->wire_count = 0; 1967 if (m >= m_tmp) { 1968 m->object = NULL; 1969 m->oflags |= VPO_UNMANAGED; 1970 } 1971 m->busy_lock = VPB_UNBUSIED; 1972 vm_page_free(m); 1973 } 1974 return (NULL); 1975 } 1976 } else 1977 m->pindex = pindex; 1978 if (memattr != VM_MEMATTR_DEFAULT) 1979 pmap_page_set_memattr(m, memattr); 1980 pindex++; 1981 } 1982 vm_page_alloc_contig_vdrop(&deferred_vdrop_list); 1983 if (vm_paging_needed()) 1984 pagedaemon_wakeup(); 1985 return (m_ret); 1986 } 1987 1988 /* 1989 * Initialize a page that has been freshly dequeued from a freelist. 1990 * The caller has to drop the vnode returned, if it is not NULL. 1991 * 1992 * This function may only be used to initialize unmanaged pages. 1993 * 1994 * To be called with vm_page_queue_free_mtx held. 1995 */ 1996 static struct vnode * 1997 vm_page_alloc_init(vm_page_t m) 1998 { 1999 struct vnode *drop; 2000 vm_object_t m_object; 2001 2002 KASSERT(m->queue == PQ_NONE, 2003 ("vm_page_alloc_init: page %p has unexpected queue %d", 2004 m, m->queue)); 2005 KASSERT(m->wire_count == 0, 2006 ("vm_page_alloc_init: page %p is wired", m)); 2007 KASSERT(m->hold_count == 0, 2008 ("vm_page_alloc_init: page %p is held", m)); 2009 KASSERT(!vm_page_sbusied(m), 2010 ("vm_page_alloc_init: page %p is busy", m)); 2011 KASSERT(m->dirty == 0, 2012 ("vm_page_alloc_init: page %p is dirty", m)); 2013 KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, 2014 ("vm_page_alloc_init: page %p has unexpected memattr %d", 2015 m, pmap_page_get_memattr(m))); 2016 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 2017 drop = NULL; 2018 if ((m->flags & PG_CACHED) != 0) { 2019 KASSERT((m->flags & PG_ZERO) == 0, 2020 ("vm_page_alloc_init: cached page %p is PG_ZERO", m)); 2021 m->valid = 0; 2022 m_object = m->object; 2023 vm_page_cache_remove(m); 2024 if (m_object->type == OBJT_VNODE && 2025 vm_object_cache_is_empty(m_object)) 2026 drop = m_object->handle; 2027 } else { 2028 KASSERT(m->valid == 0, 2029 ("vm_page_alloc_init: free page %p is valid", m)); 2030 vm_phys_freecnt_adj(m, -1); 2031 if ((m->flags & PG_ZERO) != 0) 2032 vm_page_zero_count--; 2033 } 2034 return (drop); 2035 } 2036 2037 /* 2038 * vm_page_alloc_freelist: 2039 * 2040 * Allocate a physical page from the specified free page list. 2041 * 2042 * The caller must always specify an allocation class. 2043 * 2044 * allocation classes: 2045 * VM_ALLOC_NORMAL normal process request 2046 * VM_ALLOC_SYSTEM system *really* needs a page 2047 * VM_ALLOC_INTERRUPT interrupt time request 2048 * 2049 * optional allocation flags: 2050 * VM_ALLOC_COUNT(number) the number of additional pages that the caller 2051 * intends to allocate 2052 * VM_ALLOC_WIRED wire the allocated page 2053 * VM_ALLOC_ZERO prefer a zeroed page 2054 * 2055 * This routine may not sleep. 2056 */ 2057 vm_page_t 2058 vm_page_alloc_freelist(int flind, int req) 2059 { 2060 struct vnode *drop; 2061 vm_page_t m; 2062 u_int flags; 2063 int req_class; 2064 2065 req_class = req & VM_ALLOC_CLASS_MASK; 2066 2067 /* 2068 * The page daemon is allowed to dig deeper into the free page list. 2069 */ 2070 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 2071 req_class = VM_ALLOC_SYSTEM; 2072 2073 /* 2074 * Do not allocate reserved pages unless the req has asked for it. 2075 */ 2076 mtx_lock_flags(&vm_page_queue_free_mtx, MTX_RECURSE); 2077 if (vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_free_reserved || 2078 (req_class == VM_ALLOC_SYSTEM && 2079 vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_interrupt_free_min) || 2080 (req_class == VM_ALLOC_INTERRUPT && 2081 vm_cnt.v_free_count + vm_cnt.v_cache_count > 0)) 2082 m = vm_phys_alloc_freelist_pages(flind, VM_FREEPOOL_DIRECT, 0); 2083 else { 2084 mtx_unlock(&vm_page_queue_free_mtx); 2085 atomic_add_int(&vm_pageout_deficit, 2086 max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1)); 2087 pagedaemon_wakeup(); 2088 return (NULL); 2089 } 2090 if (m == NULL) { 2091 mtx_unlock(&vm_page_queue_free_mtx); 2092 return (NULL); 2093 } 2094 drop = vm_page_alloc_init(m); 2095 mtx_unlock(&vm_page_queue_free_mtx); 2096 2097 /* 2098 * Initialize the page. Only the PG_ZERO flag is inherited. 2099 */ 2100 m->aflags = 0; 2101 flags = 0; 2102 if ((req & VM_ALLOC_ZERO) != 0) 2103 flags = PG_ZERO; 2104 m->flags &= flags; 2105 if ((req & VM_ALLOC_WIRED) != 0) { 2106 /* 2107 * The page lock is not required for wiring a page that does 2108 * not belong to an object. 2109 */ 2110 atomic_add_int(&vm_cnt.v_wire_count, 1); 2111 m->wire_count = 1; 2112 } 2113 /* Unmanaged pages don't use "act_count". */ 2114 m->oflags = VPO_UNMANAGED; 2115 if (drop != NULL) 2116 vdrop(drop); 2117 if (vm_paging_needed()) 2118 pagedaemon_wakeup(); 2119 return (m); 2120 } 2121 2122 #define VPSC_ANY 0 /* No restrictions. */ 2123 #define VPSC_NORESERV 1 /* Skip reservations; implies VPSC_NOSUPER. */ 2124 #define VPSC_NOSUPER 2 /* Skip superpages. */ 2125 2126 /* 2127 * vm_page_scan_contig: 2128 * 2129 * Scan vm_page_array[] between the specified entries "m_start" and 2130 * "m_end" for a run of contiguous physical pages that satisfy the 2131 * specified conditions, and return the lowest page in the run. The 2132 * specified "alignment" determines the alignment of the lowest physical 2133 * page in the run. If the specified "boundary" is non-zero, then the 2134 * run of physical pages cannot span a physical address that is a 2135 * multiple of "boundary". 2136 * 2137 * "m_end" is never dereferenced, so it need not point to a vm_page 2138 * structure within vm_page_array[]. 2139 * 2140 * "npages" must be greater than zero. "m_start" and "m_end" must not 2141 * span a hole (or discontiguity) in the physical address space. Both 2142 * "alignment" and "boundary" must be a power of two. 2143 */ 2144 vm_page_t 2145 vm_page_scan_contig(u_long npages, vm_page_t m_start, vm_page_t m_end, 2146 u_long alignment, vm_paddr_t boundary, int options) 2147 { 2148 struct mtx *m_mtx, *new_mtx; 2149 vm_object_t object; 2150 vm_paddr_t pa; 2151 vm_page_t m, m_run; 2152 #if VM_NRESERVLEVEL > 0 2153 int level; 2154 #endif 2155 int m_inc, order, run_ext, run_len; 2156 2157 KASSERT(npages > 0, ("npages is 0")); 2158 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 2159 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 2160 m_run = NULL; 2161 run_len = 0; 2162 m_mtx = NULL; 2163 for (m = m_start; m < m_end && run_len < npages; m += m_inc) { 2164 KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0, 2165 ("page %p is PG_FICTITIOUS or PG_MARKER", m)); 2166 2167 /* 2168 * If the current page would be the start of a run, check its 2169 * physical address against the end, alignment, and boundary 2170 * conditions. If it doesn't satisfy these conditions, either 2171 * terminate the scan or advance to the next page that 2172 * satisfies the failed condition. 2173 */ 2174 if (run_len == 0) { 2175 KASSERT(m_run == NULL, ("m_run != NULL")); 2176 if (m + npages > m_end) 2177 break; 2178 pa = VM_PAGE_TO_PHYS(m); 2179 if ((pa & (alignment - 1)) != 0) { 2180 m_inc = atop(roundup2(pa, alignment) - pa); 2181 continue; 2182 } 2183 if (rounddown2(pa ^ (pa + ptoa(npages) - 1), 2184 boundary) != 0) { 2185 m_inc = atop(roundup2(pa, boundary) - pa); 2186 continue; 2187 } 2188 } else 2189 KASSERT(m_run != NULL, ("m_run == NULL")); 2190 2191 /* 2192 * Avoid releasing and reacquiring the same page lock. 2193 */ 2194 new_mtx = vm_page_lockptr(m); 2195 if (m_mtx != new_mtx) { 2196 if (m_mtx != NULL) 2197 mtx_unlock(m_mtx); 2198 m_mtx = new_mtx; 2199 mtx_lock(m_mtx); 2200 } 2201 m_inc = 1; 2202 retry: 2203 if (m->wire_count != 0 || m->hold_count != 0) 2204 run_ext = 0; 2205 #if VM_NRESERVLEVEL > 0 2206 else if ((level = vm_reserv_level(m)) >= 0 && 2207 (options & VPSC_NORESERV) != 0) { 2208 run_ext = 0; 2209 /* Advance to the end of the reservation. */ 2210 pa = VM_PAGE_TO_PHYS(m); 2211 m_inc = atop(roundup2(pa + 1, vm_reserv_size(level)) - 2212 pa); 2213 } 2214 #endif 2215 else if ((object = m->object) != NULL) { 2216 /* 2217 * The page is considered eligible for relocation if 2218 * and only if it could be laundered or reclaimed by 2219 * the page daemon. 2220 */ 2221 if (!VM_OBJECT_TRYRLOCK(object)) { 2222 mtx_unlock(m_mtx); 2223 VM_OBJECT_RLOCK(object); 2224 mtx_lock(m_mtx); 2225 if (m->object != object) { 2226 /* 2227 * The page may have been freed. 2228 */ 2229 VM_OBJECT_RUNLOCK(object); 2230 goto retry; 2231 } else if (m->wire_count != 0 || 2232 m->hold_count != 0) { 2233 run_ext = 0; 2234 goto unlock; 2235 } 2236 } 2237 KASSERT((m->flags & PG_UNHOLDFREE) == 0, 2238 ("page %p is PG_UNHOLDFREE", m)); 2239 /* Don't care: PG_NODUMP, PG_WINATCFLS, PG_ZERO. */ 2240 if (object->type != OBJT_DEFAULT && 2241 object->type != OBJT_SWAP && 2242 object->type != OBJT_VNODE) 2243 run_ext = 0; 2244 else if ((m->flags & PG_CACHED) != 0 || 2245 m != vm_page_lookup(object, m->pindex)) { 2246 /* 2247 * The page is cached or recently converted 2248 * from cached to free. 2249 */ 2250 #if VM_NRESERVLEVEL > 0 2251 if (level >= 0) { 2252 /* 2253 * The page is reserved. Extend the 2254 * current run by one page. 2255 */ 2256 run_ext = 1; 2257 } else 2258 #endif 2259 if ((order = m->order) < VM_NFREEORDER) { 2260 /* 2261 * The page is enqueued in the 2262 * physical memory allocator's cache/ 2263 * free page queues. Moreover, it is 2264 * the first page in a power-of-two- 2265 * sized run of contiguous cache/free 2266 * pages. Add these pages to the end 2267 * of the current run, and jump 2268 * ahead. 2269 */ 2270 run_ext = 1 << order; 2271 m_inc = 1 << order; 2272 } else 2273 run_ext = 0; 2274 #if VM_NRESERVLEVEL > 0 2275 } else if ((options & VPSC_NOSUPER) != 0 && 2276 (level = vm_reserv_level_iffullpop(m)) >= 0) { 2277 run_ext = 0; 2278 /* Advance to the end of the superpage. */ 2279 pa = VM_PAGE_TO_PHYS(m); 2280 m_inc = atop(roundup2(pa + 1, 2281 vm_reserv_size(level)) - pa); 2282 #endif 2283 } else if (object->memattr == VM_MEMATTR_DEFAULT && 2284 m->queue != PQ_NONE && !vm_page_busied(m)) { 2285 /* 2286 * The page is allocated but eligible for 2287 * relocation. Extend the current run by one 2288 * page. 2289 */ 2290 KASSERT(pmap_page_get_memattr(m) == 2291 VM_MEMATTR_DEFAULT, 2292 ("page %p has an unexpected memattr", m)); 2293 KASSERT((m->oflags & (VPO_SWAPINPROG | 2294 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, 2295 ("page %p has unexpected oflags", m)); 2296 /* Don't care: VPO_NOSYNC. */ 2297 run_ext = 1; 2298 } else 2299 run_ext = 0; 2300 unlock: 2301 VM_OBJECT_RUNLOCK(object); 2302 #if VM_NRESERVLEVEL > 0 2303 } else if (level >= 0) { 2304 /* 2305 * The page is reserved but not yet allocated. In 2306 * other words, it is still cached or free. Extend 2307 * the current run by one page. 2308 */ 2309 run_ext = 1; 2310 #endif 2311 } else if ((order = m->order) < VM_NFREEORDER) { 2312 /* 2313 * The page is enqueued in the physical memory 2314 * allocator's cache/free page queues. Moreover, it 2315 * is the first page in a power-of-two-sized run of 2316 * contiguous cache/free pages. Add these pages to 2317 * the end of the current run, and jump ahead. 2318 */ 2319 run_ext = 1 << order; 2320 m_inc = 1 << order; 2321 } else { 2322 /* 2323 * Skip the page for one of the following reasons: (1) 2324 * It is enqueued in the physical memory allocator's 2325 * cache/free page queues. However, it is not the 2326 * first page in a run of contiguous cache/free pages. 2327 * (This case rarely occurs because the scan is 2328 * performed in ascending order.) (2) It is not 2329 * reserved, and it is transitioning from free to 2330 * allocated. (Conversely, the transition from 2331 * allocated to free for managed pages is blocked by 2332 * the page lock.) (3) It is allocated but not 2333 * contained by an object and not wired, e.g., 2334 * allocated by Xen's balloon driver. 2335 */ 2336 run_ext = 0; 2337 } 2338 2339 /* 2340 * Extend or reset the current run of pages. 2341 */ 2342 if (run_ext > 0) { 2343 if (run_len == 0) 2344 m_run = m; 2345 run_len += run_ext; 2346 } else { 2347 if (run_len > 0) { 2348 m_run = NULL; 2349 run_len = 0; 2350 } 2351 } 2352 } 2353 if (m_mtx != NULL) 2354 mtx_unlock(m_mtx); 2355 if (run_len >= npages) 2356 return (m_run); 2357 return (NULL); 2358 } 2359 2360 /* 2361 * vm_page_reclaim_run: 2362 * 2363 * Try to relocate each of the allocated virtual pages within the 2364 * specified run of physical pages to a new physical address. Free the 2365 * physical pages underlying the relocated virtual pages. A virtual page 2366 * is relocatable if and only if it could be laundered or reclaimed by 2367 * the page daemon. Whenever possible, a virtual page is relocated to a 2368 * physical address above "high". 2369 * 2370 * Returns 0 if every physical page within the run was already free or 2371 * just freed by a successful relocation. Otherwise, returns a non-zero 2372 * value indicating why the last attempt to relocate a virtual page was 2373 * unsuccessful. 2374 * 2375 * "req_class" must be an allocation class. 2376 */ 2377 static int 2378 vm_page_reclaim_run(int req_class, u_long npages, vm_page_t m_run, 2379 vm_paddr_t high) 2380 { 2381 struct mtx *m_mtx, *new_mtx; 2382 struct spglist free; 2383 vm_object_t object; 2384 vm_paddr_t pa; 2385 vm_page_t m, m_end, m_new; 2386 int error, order, req; 2387 2388 KASSERT((req_class & VM_ALLOC_CLASS_MASK) == req_class, 2389 ("req_class is not an allocation class")); 2390 SLIST_INIT(&free); 2391 error = 0; 2392 m = m_run; 2393 m_end = m_run + npages; 2394 m_mtx = NULL; 2395 for (; error == 0 && m < m_end; m++) { 2396 KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0, 2397 ("page %p is PG_FICTITIOUS or PG_MARKER", m)); 2398 2399 /* 2400 * Avoid releasing and reacquiring the same page lock. 2401 */ 2402 new_mtx = vm_page_lockptr(m); 2403 if (m_mtx != new_mtx) { 2404 if (m_mtx != NULL) 2405 mtx_unlock(m_mtx); 2406 m_mtx = new_mtx; 2407 mtx_lock(m_mtx); 2408 } 2409 retry: 2410 if (m->wire_count != 0 || m->hold_count != 0) 2411 error = EBUSY; 2412 else if ((object = m->object) != NULL) { 2413 /* 2414 * The page is relocated if and only if it could be 2415 * laundered or reclaimed by the page daemon. 2416 */ 2417 if (!VM_OBJECT_TRYWLOCK(object)) { 2418 mtx_unlock(m_mtx); 2419 VM_OBJECT_WLOCK(object); 2420 mtx_lock(m_mtx); 2421 if (m->object != object) { 2422 /* 2423 * The page may have been freed. 2424 */ 2425 VM_OBJECT_WUNLOCK(object); 2426 goto retry; 2427 } else if (m->wire_count != 0 || 2428 m->hold_count != 0) { 2429 error = EBUSY; 2430 goto unlock; 2431 } 2432 } 2433 KASSERT((m->flags & PG_UNHOLDFREE) == 0, 2434 ("page %p is PG_UNHOLDFREE", m)); 2435 /* Don't care: PG_NODUMP, PG_WINATCFLS, PG_ZERO. */ 2436 if (object->type != OBJT_DEFAULT && 2437 object->type != OBJT_SWAP && 2438 object->type != OBJT_VNODE) 2439 error = EINVAL; 2440 else if ((m->flags & PG_CACHED) != 0 || 2441 m != vm_page_lookup(object, m->pindex)) { 2442 /* 2443 * The page is cached or recently converted 2444 * from cached to free. 2445 */ 2446 VM_OBJECT_WUNLOCK(object); 2447 goto cached; 2448 } else if (object->memattr != VM_MEMATTR_DEFAULT) 2449 error = EINVAL; 2450 else if (m->queue != PQ_NONE && !vm_page_busied(m)) { 2451 KASSERT(pmap_page_get_memattr(m) == 2452 VM_MEMATTR_DEFAULT, 2453 ("page %p has an unexpected memattr", m)); 2454 KASSERT((m->oflags & (VPO_SWAPINPROG | 2455 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, 2456 ("page %p has unexpected oflags", m)); 2457 /* Don't care: VPO_NOSYNC. */ 2458 if (m->valid != 0) { 2459 /* 2460 * First, try to allocate a new page 2461 * that is above "high". Failing 2462 * that, try to allocate a new page 2463 * that is below "m_run". Allocate 2464 * the new page between the end of 2465 * "m_run" and "high" only as a last 2466 * resort. 2467 */ 2468 req = req_class | VM_ALLOC_NOOBJ; 2469 if ((m->flags & PG_NODUMP) != 0) 2470 req |= VM_ALLOC_NODUMP; 2471 if (trunc_page(high) != 2472 ~(vm_paddr_t)PAGE_MASK) { 2473 m_new = vm_page_alloc_contig( 2474 NULL, 0, req, 1, 2475 round_page(high), 2476 ~(vm_paddr_t)0, 2477 PAGE_SIZE, 0, 2478 VM_MEMATTR_DEFAULT); 2479 } else 2480 m_new = NULL; 2481 if (m_new == NULL) { 2482 pa = VM_PAGE_TO_PHYS(m_run); 2483 m_new = vm_page_alloc_contig( 2484 NULL, 0, req, 1, 2485 0, pa - 1, PAGE_SIZE, 0, 2486 VM_MEMATTR_DEFAULT); 2487 } 2488 if (m_new == NULL) { 2489 pa += ptoa(npages); 2490 m_new = vm_page_alloc_contig( 2491 NULL, 0, req, 1, 2492 pa, high, PAGE_SIZE, 0, 2493 VM_MEMATTR_DEFAULT); 2494 } 2495 if (m_new == NULL) { 2496 error = ENOMEM; 2497 goto unlock; 2498 } 2499 KASSERT(m_new->wire_count == 0, 2500 ("page %p is wired", m)); 2501 2502 /* 2503 * Replace "m" with the new page. For 2504 * vm_page_replace(), "m" must be busy 2505 * and dequeued. Finally, change "m" 2506 * as if vm_page_free() was called. 2507 */ 2508 if (object->ref_count != 0) 2509 pmap_remove_all(m); 2510 m_new->aflags = m->aflags; 2511 KASSERT(m_new->oflags == VPO_UNMANAGED, 2512 ("page %p is managed", m)); 2513 m_new->oflags = m->oflags & VPO_NOSYNC; 2514 pmap_copy_page(m, m_new); 2515 m_new->valid = m->valid; 2516 m_new->dirty = m->dirty; 2517 m->flags &= ~PG_ZERO; 2518 vm_page_xbusy(m); 2519 vm_page_remque(m); 2520 vm_page_replace_checked(m_new, object, 2521 m->pindex, m); 2522 m->valid = 0; 2523 vm_page_undirty(m); 2524 2525 /* 2526 * The new page must be deactivated 2527 * before the object is unlocked. 2528 */ 2529 new_mtx = vm_page_lockptr(m_new); 2530 if (m_mtx != new_mtx) { 2531 mtx_unlock(m_mtx); 2532 m_mtx = new_mtx; 2533 mtx_lock(m_mtx); 2534 } 2535 vm_page_deactivate(m_new); 2536 } else { 2537 m->flags &= ~PG_ZERO; 2538 vm_page_remque(m); 2539 vm_page_remove(m); 2540 KASSERT(m->dirty == 0, 2541 ("page %p is dirty", m)); 2542 } 2543 SLIST_INSERT_HEAD(&free, m, plinks.s.ss); 2544 } else 2545 error = EBUSY; 2546 unlock: 2547 VM_OBJECT_WUNLOCK(object); 2548 } else { 2549 cached: 2550 mtx_lock(&vm_page_queue_free_mtx); 2551 order = m->order; 2552 if (order < VM_NFREEORDER) { 2553 /* 2554 * The page is enqueued in the physical memory 2555 * allocator's cache/free page queues. 2556 * Moreover, it is the first page in a power- 2557 * of-two-sized run of contiguous cache/free 2558 * pages. Jump ahead to the last page within 2559 * that run, and continue from there. 2560 */ 2561 m += (1 << order) - 1; 2562 } 2563 #if VM_NRESERVLEVEL > 0 2564 else if (vm_reserv_is_page_free(m)) 2565 order = 0; 2566 #endif 2567 mtx_unlock(&vm_page_queue_free_mtx); 2568 if (order == VM_NFREEORDER) 2569 error = EINVAL; 2570 } 2571 } 2572 if (m_mtx != NULL) 2573 mtx_unlock(m_mtx); 2574 if ((m = SLIST_FIRST(&free)) != NULL) { 2575 mtx_lock(&vm_page_queue_free_mtx); 2576 do { 2577 SLIST_REMOVE_HEAD(&free, plinks.s.ss); 2578 vm_phys_freecnt_adj(m, 1); 2579 #if VM_NRESERVLEVEL > 0 2580 if (!vm_reserv_free_page(m)) 2581 #else 2582 if (true) 2583 #endif 2584 vm_phys_free_pages(m, 0); 2585 } while ((m = SLIST_FIRST(&free)) != NULL); 2586 vm_page_zero_idle_wakeup(); 2587 vm_page_free_wakeup(); 2588 mtx_unlock(&vm_page_queue_free_mtx); 2589 } 2590 return (error); 2591 } 2592 2593 #define NRUNS 16 2594 2595 CTASSERT(powerof2(NRUNS)); 2596 2597 #define RUN_INDEX(count) ((count) & (NRUNS - 1)) 2598 2599 #define MIN_RECLAIM 8 2600 2601 /* 2602 * vm_page_reclaim_contig: 2603 * 2604 * Reclaim allocated, contiguous physical memory satisfying the specified 2605 * conditions by relocating the virtual pages using that physical memory. 2606 * Returns true if reclamation is successful and false otherwise. Since 2607 * relocation requires the allocation of physical pages, reclamation may 2608 * fail due to a shortage of cache/free pages. When reclamation fails, 2609 * callers are expected to perform VM_WAIT before retrying a failed 2610 * allocation operation, e.g., vm_page_alloc_contig(). 2611 * 2612 * The caller must always specify an allocation class through "req". 2613 * 2614 * allocation classes: 2615 * VM_ALLOC_NORMAL normal process request 2616 * VM_ALLOC_SYSTEM system *really* needs a page 2617 * VM_ALLOC_INTERRUPT interrupt time request 2618 * 2619 * The optional allocation flags are ignored. 2620 * 2621 * "npages" must be greater than zero. Both "alignment" and "boundary" 2622 * must be a power of two. 2623 */ 2624 bool 2625 vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low, vm_paddr_t high, 2626 u_long alignment, vm_paddr_t boundary) 2627 { 2628 vm_paddr_t curr_low; 2629 vm_page_t m_run, m_runs[NRUNS]; 2630 u_long count, reclaimed; 2631 int error, i, options, req_class; 2632 2633 KASSERT(npages > 0, ("npages is 0")); 2634 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 2635 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 2636 req_class = req & VM_ALLOC_CLASS_MASK; 2637 2638 /* 2639 * The page daemon is allowed to dig deeper into the free page list. 2640 */ 2641 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 2642 req_class = VM_ALLOC_SYSTEM; 2643 2644 /* 2645 * Return if the number of cached and free pages cannot satisfy the 2646 * requested allocation. 2647 */ 2648 count = vm_cnt.v_free_count + vm_cnt.v_cache_count; 2649 if (count < npages + vm_cnt.v_free_reserved || (count < npages + 2650 vm_cnt.v_interrupt_free_min && req_class == VM_ALLOC_SYSTEM) || 2651 (count < npages && req_class == VM_ALLOC_INTERRUPT)) 2652 return (false); 2653 2654 /* 2655 * Scan up to three times, relaxing the restrictions ("options") on 2656 * the reclamation of reservations and superpages each time. 2657 */ 2658 for (options = VPSC_NORESERV;;) { 2659 /* 2660 * Find the highest runs that satisfy the given constraints 2661 * and restrictions, and record them in "m_runs". 2662 */ 2663 curr_low = low; 2664 count = 0; 2665 for (;;) { 2666 m_run = vm_phys_scan_contig(npages, curr_low, high, 2667 alignment, boundary, options); 2668 if (m_run == NULL) 2669 break; 2670 curr_low = VM_PAGE_TO_PHYS(m_run) + ptoa(npages); 2671 m_runs[RUN_INDEX(count)] = m_run; 2672 count++; 2673 } 2674 2675 /* 2676 * Reclaim the highest runs in LIFO (descending) order until 2677 * the number of reclaimed pages, "reclaimed", is at least 2678 * MIN_RECLAIM. Reset "reclaimed" each time because each 2679 * reclamation is idempotent, and runs will (likely) recur 2680 * from one scan to the next as restrictions are relaxed. 2681 */ 2682 reclaimed = 0; 2683 for (i = 0; count > 0 && i < NRUNS; i++) { 2684 count--; 2685 m_run = m_runs[RUN_INDEX(count)]; 2686 error = vm_page_reclaim_run(req_class, npages, m_run, 2687 high); 2688 if (error == 0) { 2689 reclaimed += npages; 2690 if (reclaimed >= MIN_RECLAIM) 2691 return (true); 2692 } 2693 } 2694 2695 /* 2696 * Either relax the restrictions on the next scan or return if 2697 * the last scan had no restrictions. 2698 */ 2699 if (options == VPSC_NORESERV) 2700 options = VPSC_NOSUPER; 2701 else if (options == VPSC_NOSUPER) 2702 options = VPSC_ANY; 2703 else if (options == VPSC_ANY) 2704 return (reclaimed != 0); 2705 } 2706 } 2707 2708 /* 2709 * vm_wait: (also see VM_WAIT macro) 2710 * 2711 * Sleep until free pages are available for allocation. 2712 * - Called in various places before memory allocations. 2713 */ 2714 void 2715 vm_wait(void) 2716 { 2717 2718 mtx_lock(&vm_page_queue_free_mtx); 2719 if (curproc == pageproc) { 2720 vm_pageout_pages_needed = 1; 2721 msleep(&vm_pageout_pages_needed, &vm_page_queue_free_mtx, 2722 PDROP | PSWP, "VMWait", 0); 2723 } else { 2724 if (!vm_pageout_wanted) { 2725 vm_pageout_wanted = true; 2726 wakeup(&vm_pageout_wanted); 2727 } 2728 vm_pages_needed = true; 2729 msleep(&vm_cnt.v_free_count, &vm_page_queue_free_mtx, PDROP | PVM, 2730 "vmwait", 0); 2731 } 2732 } 2733 2734 /* 2735 * vm_waitpfault: (also see VM_WAITPFAULT macro) 2736 * 2737 * Sleep until free pages are available for allocation. 2738 * - Called only in vm_fault so that processes page faulting 2739 * can be easily tracked. 2740 * - Sleeps at a lower priority than vm_wait() so that vm_wait()ing 2741 * processes will be able to grab memory first. Do not change 2742 * this balance without careful testing first. 2743 */ 2744 void 2745 vm_waitpfault(void) 2746 { 2747 2748 mtx_lock(&vm_page_queue_free_mtx); 2749 if (!vm_pageout_wanted) { 2750 vm_pageout_wanted = true; 2751 wakeup(&vm_pageout_wanted); 2752 } 2753 vm_pages_needed = true; 2754 msleep(&vm_cnt.v_free_count, &vm_page_queue_free_mtx, PDROP | PUSER, 2755 "pfault", 0); 2756 } 2757 2758 struct vm_pagequeue * 2759 vm_page_pagequeue(vm_page_t m) 2760 { 2761 2762 return (&vm_phys_domain(m)->vmd_pagequeues[m->queue]); 2763 } 2764 2765 /* 2766 * vm_page_dequeue: 2767 * 2768 * Remove the given page from its current page queue. 2769 * 2770 * The page must be locked. 2771 */ 2772 void 2773 vm_page_dequeue(vm_page_t m) 2774 { 2775 struct vm_pagequeue *pq; 2776 2777 vm_page_assert_locked(m); 2778 KASSERT(m->queue < PQ_COUNT, ("vm_page_dequeue: page %p is not queued", 2779 m)); 2780 pq = vm_page_pagequeue(m); 2781 vm_pagequeue_lock(pq); 2782 m->queue = PQ_NONE; 2783 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2784 vm_pagequeue_cnt_dec(pq); 2785 vm_pagequeue_unlock(pq); 2786 } 2787 2788 /* 2789 * vm_page_dequeue_locked: 2790 * 2791 * Remove the given page from its current page queue. 2792 * 2793 * The page and page queue must be locked. 2794 */ 2795 void 2796 vm_page_dequeue_locked(vm_page_t m) 2797 { 2798 struct vm_pagequeue *pq; 2799 2800 vm_page_lock_assert(m, MA_OWNED); 2801 pq = vm_page_pagequeue(m); 2802 vm_pagequeue_assert_locked(pq); 2803 m->queue = PQ_NONE; 2804 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2805 vm_pagequeue_cnt_dec(pq); 2806 } 2807 2808 /* 2809 * vm_page_enqueue: 2810 * 2811 * Add the given page to the specified page queue. 2812 * 2813 * The page must be locked. 2814 */ 2815 static void 2816 vm_page_enqueue(uint8_t queue, vm_page_t m) 2817 { 2818 struct vm_pagequeue *pq; 2819 2820 vm_page_lock_assert(m, MA_OWNED); 2821 KASSERT(queue < PQ_COUNT, 2822 ("vm_page_enqueue: invalid queue %u request for page %p", 2823 queue, m)); 2824 pq = &vm_phys_domain(m)->vmd_pagequeues[queue]; 2825 vm_pagequeue_lock(pq); 2826 m->queue = queue; 2827 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 2828 vm_pagequeue_cnt_inc(pq); 2829 vm_pagequeue_unlock(pq); 2830 } 2831 2832 /* 2833 * vm_page_requeue: 2834 * 2835 * Move the given page to the tail of its current page queue. 2836 * 2837 * The page must be locked. 2838 */ 2839 void 2840 vm_page_requeue(vm_page_t m) 2841 { 2842 struct vm_pagequeue *pq; 2843 2844 vm_page_lock_assert(m, MA_OWNED); 2845 KASSERT(m->queue != PQ_NONE, 2846 ("vm_page_requeue: page %p is not queued", m)); 2847 pq = vm_page_pagequeue(m); 2848 vm_pagequeue_lock(pq); 2849 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2850 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 2851 vm_pagequeue_unlock(pq); 2852 } 2853 2854 /* 2855 * vm_page_requeue_locked: 2856 * 2857 * Move the given page to the tail of its current page queue. 2858 * 2859 * The page queue must be locked. 2860 */ 2861 void 2862 vm_page_requeue_locked(vm_page_t m) 2863 { 2864 struct vm_pagequeue *pq; 2865 2866 KASSERT(m->queue != PQ_NONE, 2867 ("vm_page_requeue_locked: page %p is not queued", m)); 2868 pq = vm_page_pagequeue(m); 2869 vm_pagequeue_assert_locked(pq); 2870 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2871 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 2872 } 2873 2874 /* 2875 * vm_page_activate: 2876 * 2877 * Put the specified page on the active list (if appropriate). 2878 * Ensure that act_count is at least ACT_INIT but do not otherwise 2879 * mess with it. 2880 * 2881 * The page must be locked. 2882 */ 2883 void 2884 vm_page_activate(vm_page_t m) 2885 { 2886 int queue; 2887 2888 vm_page_lock_assert(m, MA_OWNED); 2889 if ((queue = m->queue) != PQ_ACTIVE) { 2890 if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) { 2891 if (m->act_count < ACT_INIT) 2892 m->act_count = ACT_INIT; 2893 if (queue != PQ_NONE) 2894 vm_page_dequeue(m); 2895 vm_page_enqueue(PQ_ACTIVE, m); 2896 } else 2897 KASSERT(queue == PQ_NONE, 2898 ("vm_page_activate: wired page %p is queued", m)); 2899 } else { 2900 if (m->act_count < ACT_INIT) 2901 m->act_count = ACT_INIT; 2902 } 2903 } 2904 2905 /* 2906 * vm_page_free_wakeup: 2907 * 2908 * Helper routine for vm_page_free_toq() and vm_page_cache(). This 2909 * routine is called when a page has been added to the cache or free 2910 * queues. 2911 * 2912 * The page queues must be locked. 2913 */ 2914 static inline void 2915 vm_page_free_wakeup(void) 2916 { 2917 2918 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 2919 /* 2920 * if pageout daemon needs pages, then tell it that there are 2921 * some free. 2922 */ 2923 if (vm_pageout_pages_needed && 2924 vm_cnt.v_cache_count + vm_cnt.v_free_count >= vm_cnt.v_pageout_free_min) { 2925 wakeup(&vm_pageout_pages_needed); 2926 vm_pageout_pages_needed = 0; 2927 } 2928 /* 2929 * wakeup processes that are waiting on memory if we hit a 2930 * high water mark. And wakeup scheduler process if we have 2931 * lots of memory. this process will swapin processes. 2932 */ 2933 if (vm_pages_needed && !vm_page_count_min()) { 2934 vm_pages_needed = false; 2935 wakeup(&vm_cnt.v_free_count); 2936 } 2937 } 2938 2939 /* 2940 * Turn a cached page into a free page, by changing its attributes. 2941 * Keep the statistics up-to-date. 2942 * 2943 * The free page queue must be locked. 2944 */ 2945 static void 2946 vm_page_cache_turn_free(vm_page_t m) 2947 { 2948 2949 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 2950 2951 m->object = NULL; 2952 m->valid = 0; 2953 KASSERT((m->flags & PG_CACHED) != 0, 2954 ("vm_page_cache_turn_free: page %p is not cached", m)); 2955 m->flags &= ~PG_CACHED; 2956 vm_cnt.v_cache_count--; 2957 vm_phys_freecnt_adj(m, 1); 2958 } 2959 2960 /* 2961 * vm_page_free_toq: 2962 * 2963 * Returns the given page to the free list, 2964 * disassociating it with any VM object. 2965 * 2966 * The object must be locked. The page must be locked if it is managed. 2967 */ 2968 void 2969 vm_page_free_toq(vm_page_t m) 2970 { 2971 2972 if ((m->oflags & VPO_UNMANAGED) == 0) { 2973 vm_page_lock_assert(m, MA_OWNED); 2974 KASSERT(!pmap_page_is_mapped(m), 2975 ("vm_page_free_toq: freeing mapped page %p", m)); 2976 } else 2977 KASSERT(m->queue == PQ_NONE, 2978 ("vm_page_free_toq: unmanaged page %p is queued", m)); 2979 PCPU_INC(cnt.v_tfree); 2980 2981 if (vm_page_sbusied(m)) 2982 panic("vm_page_free: freeing busy page %p", m); 2983 2984 /* 2985 * Unqueue, then remove page. Note that we cannot destroy 2986 * the page here because we do not want to call the pager's 2987 * callback routine until after we've put the page on the 2988 * appropriate free queue. 2989 */ 2990 vm_page_remque(m); 2991 vm_page_remove(m); 2992 2993 /* 2994 * If fictitious remove object association and 2995 * return, otherwise delay object association removal. 2996 */ 2997 if ((m->flags & PG_FICTITIOUS) != 0) { 2998 return; 2999 } 3000 3001 m->valid = 0; 3002 vm_page_undirty(m); 3003 3004 if (m->wire_count != 0) 3005 panic("vm_page_free: freeing wired page %p", m); 3006 if (m->hold_count != 0) { 3007 m->flags &= ~PG_ZERO; 3008 KASSERT((m->flags & PG_UNHOLDFREE) == 0, 3009 ("vm_page_free: freeing PG_UNHOLDFREE page %p", m)); 3010 m->flags |= PG_UNHOLDFREE; 3011 } else { 3012 /* 3013 * Restore the default memory attribute to the page. 3014 */ 3015 if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT) 3016 pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT); 3017 3018 /* 3019 * Insert the page into the physical memory allocator's 3020 * cache/free page queues. 3021 */ 3022 mtx_lock(&vm_page_queue_free_mtx); 3023 vm_phys_freecnt_adj(m, 1); 3024 #if VM_NRESERVLEVEL > 0 3025 if (!vm_reserv_free_page(m)) 3026 #else 3027 if (TRUE) 3028 #endif 3029 vm_phys_free_pages(m, 0); 3030 if ((m->flags & PG_ZERO) != 0) 3031 ++vm_page_zero_count; 3032 else 3033 vm_page_zero_idle_wakeup(); 3034 vm_page_free_wakeup(); 3035 mtx_unlock(&vm_page_queue_free_mtx); 3036 } 3037 } 3038 3039 /* 3040 * vm_page_wire: 3041 * 3042 * Mark this page as wired down by yet 3043 * another map, removing it from paging queues 3044 * as necessary. 3045 * 3046 * If the page is fictitious, then its wire count must remain one. 3047 * 3048 * The page must be locked. 3049 */ 3050 void 3051 vm_page_wire(vm_page_t m) 3052 { 3053 3054 /* 3055 * Only bump the wire statistics if the page is not already wired, 3056 * and only unqueue the page if it is on some queue (if it is unmanaged 3057 * it is already off the queues). 3058 */ 3059 vm_page_lock_assert(m, MA_OWNED); 3060 if ((m->flags & PG_FICTITIOUS) != 0) { 3061 KASSERT(m->wire_count == 1, 3062 ("vm_page_wire: fictitious page %p's wire count isn't one", 3063 m)); 3064 return; 3065 } 3066 if (m->wire_count == 0) { 3067 KASSERT((m->oflags & VPO_UNMANAGED) == 0 || 3068 m->queue == PQ_NONE, 3069 ("vm_page_wire: unmanaged page %p is queued", m)); 3070 vm_page_remque(m); 3071 atomic_add_int(&vm_cnt.v_wire_count, 1); 3072 } 3073 m->wire_count++; 3074 KASSERT(m->wire_count != 0, ("vm_page_wire: wire_count overflow m=%p", m)); 3075 } 3076 3077 /* 3078 * vm_page_unwire: 3079 * 3080 * Release one wiring of the specified page, potentially allowing it to be 3081 * paged out. Returns TRUE if the number of wirings transitions to zero and 3082 * FALSE otherwise. 3083 * 3084 * Only managed pages belonging to an object can be paged out. If the number 3085 * of wirings transitions to zero and the page is eligible for page out, then 3086 * the page is added to the specified paging queue (unless PQ_NONE is 3087 * specified). 3088 * 3089 * If a page is fictitious, then its wire count must always be one. 3090 * 3091 * A managed page must be locked. 3092 */ 3093 boolean_t 3094 vm_page_unwire(vm_page_t m, uint8_t queue) 3095 { 3096 3097 KASSERT(queue < PQ_COUNT || queue == PQ_NONE, 3098 ("vm_page_unwire: invalid queue %u request for page %p", 3099 queue, m)); 3100 if ((m->oflags & VPO_UNMANAGED) == 0) 3101 vm_page_assert_locked(m); 3102 if ((m->flags & PG_FICTITIOUS) != 0) { 3103 KASSERT(m->wire_count == 1, 3104 ("vm_page_unwire: fictitious page %p's wire count isn't one", m)); 3105 return (FALSE); 3106 } 3107 if (m->wire_count > 0) { 3108 m->wire_count--; 3109 if (m->wire_count == 0) { 3110 atomic_subtract_int(&vm_cnt.v_wire_count, 1); 3111 if ((m->oflags & VPO_UNMANAGED) == 0 && 3112 m->object != NULL && queue != PQ_NONE) { 3113 if (queue == PQ_INACTIVE) 3114 m->flags &= ~PG_WINATCFLS; 3115 vm_page_enqueue(queue, m); 3116 } 3117 return (TRUE); 3118 } else 3119 return (FALSE); 3120 } else 3121 panic("vm_page_unwire: page %p's wire count is zero", m); 3122 } 3123 3124 /* 3125 * Move the specified page to the inactive queue. 3126 * 3127 * Many pages placed on the inactive queue should actually go 3128 * into the cache, but it is difficult to figure out which. What 3129 * we do instead, if the inactive target is well met, is to put 3130 * clean pages at the head of the inactive queue instead of the tail. 3131 * This will cause them to be moved to the cache more quickly and 3132 * if not actively re-referenced, reclaimed more quickly. If we just 3133 * stick these pages at the end of the inactive queue, heavy filesystem 3134 * meta-data accesses can cause an unnecessary paging load on memory bound 3135 * processes. This optimization causes one-time-use metadata to be 3136 * reused more quickly. 3137 * 3138 * Normally noreuse is FALSE, resulting in LRU operation. noreuse is set 3139 * to TRUE if we want this page to be 'as if it were placed in the cache', 3140 * except without unmapping it from the process address space. In 3141 * practice this is implemented by inserting the page at the head of the 3142 * queue, using a marker page to guide FIFO insertion ordering. 3143 * 3144 * The page must be locked. 3145 */ 3146 static inline void 3147 _vm_page_deactivate(vm_page_t m, boolean_t noreuse) 3148 { 3149 struct vm_pagequeue *pq; 3150 int queue; 3151 3152 vm_page_assert_locked(m); 3153 3154 /* 3155 * Ignore if the page is already inactive, unless it is unlikely to be 3156 * reactivated. 3157 */ 3158 if ((queue = m->queue) == PQ_INACTIVE && !noreuse) 3159 return; 3160 if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) { 3161 pq = &vm_phys_domain(m)->vmd_pagequeues[PQ_INACTIVE]; 3162 /* Avoid multiple acquisitions of the inactive queue lock. */ 3163 if (queue == PQ_INACTIVE) { 3164 vm_pagequeue_lock(pq); 3165 vm_page_dequeue_locked(m); 3166 } else { 3167 if (queue != PQ_NONE) 3168 vm_page_dequeue(m); 3169 m->flags &= ~PG_WINATCFLS; 3170 vm_pagequeue_lock(pq); 3171 } 3172 m->queue = PQ_INACTIVE; 3173 if (noreuse) 3174 TAILQ_INSERT_BEFORE(&vm_phys_domain(m)->vmd_inacthead, 3175 m, plinks.q); 3176 else 3177 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 3178 vm_pagequeue_cnt_inc(pq); 3179 vm_pagequeue_unlock(pq); 3180 } 3181 } 3182 3183 /* 3184 * Move the specified page to the inactive queue. 3185 * 3186 * The page must be locked. 3187 */ 3188 void 3189 vm_page_deactivate(vm_page_t m) 3190 { 3191 3192 _vm_page_deactivate(m, FALSE); 3193 } 3194 3195 /* 3196 * Move the specified page to the inactive queue with the expectation 3197 * that it is unlikely to be reused. 3198 * 3199 * The page must be locked. 3200 */ 3201 void 3202 vm_page_deactivate_noreuse(vm_page_t m) 3203 { 3204 3205 _vm_page_deactivate(m, TRUE); 3206 } 3207 3208 /* 3209 * vm_page_try_to_cache: 3210 * 3211 * Returns 0 on failure, 1 on success 3212 */ 3213 int 3214 vm_page_try_to_cache(vm_page_t m) 3215 { 3216 3217 vm_page_lock_assert(m, MA_OWNED); 3218 VM_OBJECT_ASSERT_WLOCKED(m->object); 3219 if (m->dirty || m->hold_count || m->wire_count || 3220 (m->oflags & VPO_UNMANAGED) != 0 || vm_page_busied(m)) 3221 return (0); 3222 pmap_remove_all(m); 3223 if (m->dirty) 3224 return (0); 3225 vm_page_cache(m); 3226 return (1); 3227 } 3228 3229 /* 3230 * vm_page_try_to_free() 3231 * 3232 * Attempt to free the page. If we cannot free it, we do nothing. 3233 * 1 is returned on success, 0 on failure. 3234 */ 3235 int 3236 vm_page_try_to_free(vm_page_t m) 3237 { 3238 3239 vm_page_lock_assert(m, MA_OWNED); 3240 if (m->object != NULL) 3241 VM_OBJECT_ASSERT_WLOCKED(m->object); 3242 if (m->dirty || m->hold_count || m->wire_count || 3243 (m->oflags & VPO_UNMANAGED) != 0 || vm_page_busied(m)) 3244 return (0); 3245 pmap_remove_all(m); 3246 if (m->dirty) 3247 return (0); 3248 vm_page_free(m); 3249 return (1); 3250 } 3251 3252 /* 3253 * vm_page_cache 3254 * 3255 * Put the specified page onto the page cache queue (if appropriate). 3256 * 3257 * The object and page must be locked. 3258 */ 3259 void 3260 vm_page_cache(vm_page_t m) 3261 { 3262 vm_object_t object; 3263 boolean_t cache_was_empty; 3264 3265 vm_page_lock_assert(m, MA_OWNED); 3266 object = m->object; 3267 VM_OBJECT_ASSERT_WLOCKED(object); 3268 if (vm_page_busied(m) || (m->oflags & VPO_UNMANAGED) || 3269 m->hold_count || m->wire_count) 3270 panic("vm_page_cache: attempting to cache busy page"); 3271 KASSERT(!pmap_page_is_mapped(m), 3272 ("vm_page_cache: page %p is mapped", m)); 3273 KASSERT(m->dirty == 0, ("vm_page_cache: page %p is dirty", m)); 3274 if (m->valid == 0 || object->type == OBJT_DEFAULT || 3275 (object->type == OBJT_SWAP && 3276 !vm_pager_has_page(object, m->pindex, NULL, NULL))) { 3277 /* 3278 * Hypothesis: A cache-eligible page belonging to a 3279 * default object or swap object but without a backing 3280 * store must be zero filled. 3281 */ 3282 vm_page_free(m); 3283 return; 3284 } 3285 KASSERT((m->flags & PG_CACHED) == 0, 3286 ("vm_page_cache: page %p is already cached", m)); 3287 3288 /* 3289 * Remove the page from the paging queues. 3290 */ 3291 vm_page_remque(m); 3292 3293 /* 3294 * Remove the page from the object's collection of resident 3295 * pages. 3296 */ 3297 vm_radix_remove(&object->rtree, m->pindex); 3298 TAILQ_REMOVE(&object->memq, m, listq); 3299 object->resident_page_count--; 3300 3301 /* 3302 * Restore the default memory attribute to the page. 3303 */ 3304 if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT) 3305 pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT); 3306 3307 /* 3308 * Insert the page into the object's collection of cached pages 3309 * and the physical memory allocator's cache/free page queues. 3310 */ 3311 m->flags &= ~PG_ZERO; 3312 mtx_lock(&vm_page_queue_free_mtx); 3313 cache_was_empty = vm_radix_is_empty(&object->cache); 3314 if (vm_radix_insert(&object->cache, m)) { 3315 mtx_unlock(&vm_page_queue_free_mtx); 3316 if (object->type == OBJT_VNODE && 3317 object->resident_page_count == 0) 3318 vdrop(object->handle); 3319 m->object = NULL; 3320 vm_page_free(m); 3321 return; 3322 } 3323 3324 /* 3325 * The above call to vm_radix_insert() could reclaim the one pre- 3326 * existing cached page from this object, resulting in a call to 3327 * vdrop(). 3328 */ 3329 if (!cache_was_empty) 3330 cache_was_empty = vm_radix_is_singleton(&object->cache); 3331 3332 m->flags |= PG_CACHED; 3333 vm_cnt.v_cache_count++; 3334 PCPU_INC(cnt.v_tcached); 3335 #if VM_NRESERVLEVEL > 0 3336 if (!vm_reserv_free_page(m)) { 3337 #else 3338 if (TRUE) { 3339 #endif 3340 vm_phys_free_pages(m, 0); 3341 } 3342 vm_page_free_wakeup(); 3343 mtx_unlock(&vm_page_queue_free_mtx); 3344 3345 /* 3346 * Increment the vnode's hold count if this is the object's only 3347 * cached page. Decrement the vnode's hold count if this was 3348 * the object's only resident page. 3349 */ 3350 if (object->type == OBJT_VNODE) { 3351 if (cache_was_empty && object->resident_page_count != 0) 3352 vhold(object->handle); 3353 else if (!cache_was_empty && object->resident_page_count == 0) 3354 vdrop(object->handle); 3355 } 3356 } 3357 3358 /* 3359 * vm_page_advise 3360 * 3361 * Deactivate or do nothing, as appropriate. 3362 * 3363 * The object and page must be locked. 3364 */ 3365 void 3366 vm_page_advise(vm_page_t m, int advice) 3367 { 3368 3369 vm_page_assert_locked(m); 3370 VM_OBJECT_ASSERT_WLOCKED(m->object); 3371 if (advice == MADV_FREE) 3372 /* 3373 * Mark the page clean. This will allow the page to be freed 3374 * up by the system. However, such pages are often reused 3375 * quickly by malloc() so we do not do anything that would 3376 * cause a page fault if we can help it. 3377 * 3378 * Specifically, we do not try to actually free the page now 3379 * nor do we try to put it in the cache (which would cause a 3380 * page fault on reuse). 3381 * 3382 * But we do make the page as freeable as we can without 3383 * actually taking the step of unmapping it. 3384 */ 3385 m->dirty = 0; 3386 else if (advice != MADV_DONTNEED) 3387 return; 3388 3389 /* 3390 * Clear any references to the page. Otherwise, the page daemon will 3391 * immediately reactivate the page. 3392 */ 3393 vm_page_aflag_clear(m, PGA_REFERENCED); 3394 3395 if (advice != MADV_FREE && m->dirty == 0 && pmap_is_modified(m)) 3396 vm_page_dirty(m); 3397 3398 /* 3399 * Place clean pages at the head of the inactive queue rather than the 3400 * tail, thus defeating the queue's LRU operation and ensuring that the 3401 * page will be reused quickly. 3402 */ 3403 _vm_page_deactivate(m, m->dirty == 0); 3404 } 3405 3406 /* 3407 * Grab a page, waiting until we are waken up due to the page 3408 * changing state. We keep on waiting, if the page continues 3409 * to be in the object. If the page doesn't exist, first allocate it 3410 * and then conditionally zero it. 3411 * 3412 * This routine may sleep. 3413 * 3414 * The object must be locked on entry. The lock will, however, be released 3415 * and reacquired if the routine sleeps. 3416 */ 3417 vm_page_t 3418 vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags) 3419 { 3420 vm_page_t m; 3421 int sleep; 3422 3423 VM_OBJECT_ASSERT_WLOCKED(object); 3424 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || 3425 (allocflags & VM_ALLOC_IGN_SBUSY) != 0, 3426 ("vm_page_grab: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch")); 3427 retrylookup: 3428 if ((m = vm_page_lookup(object, pindex)) != NULL) { 3429 sleep = (allocflags & VM_ALLOC_IGN_SBUSY) != 0 ? 3430 vm_page_xbusied(m) : vm_page_busied(m); 3431 if (sleep) { 3432 if ((allocflags & VM_ALLOC_NOWAIT) != 0) 3433 return (NULL); 3434 /* 3435 * Reference the page before unlocking and 3436 * sleeping so that the page daemon is less 3437 * likely to reclaim it. 3438 */ 3439 vm_page_aflag_set(m, PGA_REFERENCED); 3440 vm_page_lock(m); 3441 VM_OBJECT_WUNLOCK(object); 3442 vm_page_busy_sleep(m, "pgrbwt"); 3443 VM_OBJECT_WLOCK(object); 3444 goto retrylookup; 3445 } else { 3446 if ((allocflags & VM_ALLOC_WIRED) != 0) { 3447 vm_page_lock(m); 3448 vm_page_wire(m); 3449 vm_page_unlock(m); 3450 } 3451 if ((allocflags & 3452 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0) 3453 vm_page_xbusy(m); 3454 if ((allocflags & VM_ALLOC_SBUSY) != 0) 3455 vm_page_sbusy(m); 3456 return (m); 3457 } 3458 } 3459 m = vm_page_alloc(object, pindex, allocflags); 3460 if (m == NULL) { 3461 if ((allocflags & VM_ALLOC_NOWAIT) != 0) 3462 return (NULL); 3463 VM_OBJECT_WUNLOCK(object); 3464 VM_WAIT; 3465 VM_OBJECT_WLOCK(object); 3466 goto retrylookup; 3467 } else if (m->valid != 0) 3468 return (m); 3469 if (allocflags & VM_ALLOC_ZERO && (m->flags & PG_ZERO) == 0) 3470 pmap_zero_page(m); 3471 return (m); 3472 } 3473 3474 /* 3475 * Mapping function for valid or dirty bits in a page. 3476 * 3477 * Inputs are required to range within a page. 3478 */ 3479 vm_page_bits_t 3480 vm_page_bits(int base, int size) 3481 { 3482 int first_bit; 3483 int last_bit; 3484 3485 KASSERT( 3486 base + size <= PAGE_SIZE, 3487 ("vm_page_bits: illegal base/size %d/%d", base, size) 3488 ); 3489 3490 if (size == 0) /* handle degenerate case */ 3491 return (0); 3492 3493 first_bit = base >> DEV_BSHIFT; 3494 last_bit = (base + size - 1) >> DEV_BSHIFT; 3495 3496 return (((vm_page_bits_t)2 << last_bit) - 3497 ((vm_page_bits_t)1 << first_bit)); 3498 } 3499 3500 /* 3501 * vm_page_set_valid_range: 3502 * 3503 * Sets portions of a page valid. The arguments are expected 3504 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive 3505 * of any partial chunks touched by the range. The invalid portion of 3506 * such chunks will be zeroed. 3507 * 3508 * (base + size) must be less then or equal to PAGE_SIZE. 3509 */ 3510 void 3511 vm_page_set_valid_range(vm_page_t m, int base, int size) 3512 { 3513 int endoff, frag; 3514 3515 VM_OBJECT_ASSERT_WLOCKED(m->object); 3516 if (size == 0) /* handle degenerate case */ 3517 return; 3518 3519 /* 3520 * If the base is not DEV_BSIZE aligned and the valid 3521 * bit is clear, we have to zero out a portion of the 3522 * first block. 3523 */ 3524 if ((frag = rounddown2(base, DEV_BSIZE)) != base && 3525 (m->valid & (1 << (base >> DEV_BSHIFT))) == 0) 3526 pmap_zero_page_area(m, frag, base - frag); 3527 3528 /* 3529 * If the ending offset is not DEV_BSIZE aligned and the 3530 * valid bit is clear, we have to zero out a portion of 3531 * the last block. 3532 */ 3533 endoff = base + size; 3534 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && 3535 (m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0) 3536 pmap_zero_page_area(m, endoff, 3537 DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); 3538 3539 /* 3540 * Assert that no previously invalid block that is now being validated 3541 * is already dirty. 3542 */ 3543 KASSERT((~m->valid & vm_page_bits(base, size) & m->dirty) == 0, 3544 ("vm_page_set_valid_range: page %p is dirty", m)); 3545 3546 /* 3547 * Set valid bits inclusive of any overlap. 3548 */ 3549 m->valid |= vm_page_bits(base, size); 3550 } 3551 3552 /* 3553 * Clear the given bits from the specified page's dirty field. 3554 */ 3555 static __inline void 3556 vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits) 3557 { 3558 uintptr_t addr; 3559 #if PAGE_SIZE < 16384 3560 int shift; 3561 #endif 3562 3563 /* 3564 * If the object is locked and the page is neither exclusive busy nor 3565 * write mapped, then the page's dirty field cannot possibly be 3566 * set by a concurrent pmap operation. 3567 */ 3568 VM_OBJECT_ASSERT_WLOCKED(m->object); 3569 if (!vm_page_xbusied(m) && !pmap_page_is_write_mapped(m)) 3570 m->dirty &= ~pagebits; 3571 else { 3572 /* 3573 * The pmap layer can call vm_page_dirty() without 3574 * holding a distinguished lock. The combination of 3575 * the object's lock and an atomic operation suffice 3576 * to guarantee consistency of the page dirty field. 3577 * 3578 * For PAGE_SIZE == 32768 case, compiler already 3579 * properly aligns the dirty field, so no forcible 3580 * alignment is needed. Only require existence of 3581 * atomic_clear_64 when page size is 32768. 3582 */ 3583 addr = (uintptr_t)&m->dirty; 3584 #if PAGE_SIZE == 32768 3585 atomic_clear_64((uint64_t *)addr, pagebits); 3586 #elif PAGE_SIZE == 16384 3587 atomic_clear_32((uint32_t *)addr, pagebits); 3588 #else /* PAGE_SIZE <= 8192 */ 3589 /* 3590 * Use a trick to perform a 32-bit atomic on the 3591 * containing aligned word, to not depend on the existence 3592 * of atomic_clear_{8, 16}. 3593 */ 3594 shift = addr & (sizeof(uint32_t) - 1); 3595 #if BYTE_ORDER == BIG_ENDIAN 3596 shift = (sizeof(uint32_t) - sizeof(m->dirty) - shift) * NBBY; 3597 #else 3598 shift *= NBBY; 3599 #endif 3600 addr &= ~(sizeof(uint32_t) - 1); 3601 atomic_clear_32((uint32_t *)addr, pagebits << shift); 3602 #endif /* PAGE_SIZE */ 3603 } 3604 } 3605 3606 /* 3607 * vm_page_set_validclean: 3608 * 3609 * Sets portions of a page valid and clean. The arguments are expected 3610 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive 3611 * of any partial chunks touched by the range. The invalid portion of 3612 * such chunks will be zero'd. 3613 * 3614 * (base + size) must be less then or equal to PAGE_SIZE. 3615 */ 3616 void 3617 vm_page_set_validclean(vm_page_t m, int base, int size) 3618 { 3619 vm_page_bits_t oldvalid, pagebits; 3620 int endoff, frag; 3621 3622 VM_OBJECT_ASSERT_WLOCKED(m->object); 3623 if (size == 0) /* handle degenerate case */ 3624 return; 3625 3626 /* 3627 * If the base is not DEV_BSIZE aligned and the valid 3628 * bit is clear, we have to zero out a portion of the 3629 * first block. 3630 */ 3631 if ((frag = rounddown2(base, DEV_BSIZE)) != base && 3632 (m->valid & ((vm_page_bits_t)1 << (base >> DEV_BSHIFT))) == 0) 3633 pmap_zero_page_area(m, frag, base - frag); 3634 3635 /* 3636 * If the ending offset is not DEV_BSIZE aligned and the 3637 * valid bit is clear, we have to zero out a portion of 3638 * the last block. 3639 */ 3640 endoff = base + size; 3641 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && 3642 (m->valid & ((vm_page_bits_t)1 << (endoff >> DEV_BSHIFT))) == 0) 3643 pmap_zero_page_area(m, endoff, 3644 DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); 3645 3646 /* 3647 * Set valid, clear dirty bits. If validating the entire 3648 * page we can safely clear the pmap modify bit. We also 3649 * use this opportunity to clear the VPO_NOSYNC flag. If a process 3650 * takes a write fault on a MAP_NOSYNC memory area the flag will 3651 * be set again. 3652 * 3653 * We set valid bits inclusive of any overlap, but we can only 3654 * clear dirty bits for DEV_BSIZE chunks that are fully within 3655 * the range. 3656 */ 3657 oldvalid = m->valid; 3658 pagebits = vm_page_bits(base, size); 3659 m->valid |= pagebits; 3660 #if 0 /* NOT YET */ 3661 if ((frag = base & (DEV_BSIZE - 1)) != 0) { 3662 frag = DEV_BSIZE - frag; 3663 base += frag; 3664 size -= frag; 3665 if (size < 0) 3666 size = 0; 3667 } 3668 pagebits = vm_page_bits(base, size & (DEV_BSIZE - 1)); 3669 #endif 3670 if (base == 0 && size == PAGE_SIZE) { 3671 /* 3672 * The page can only be modified within the pmap if it is 3673 * mapped, and it can only be mapped if it was previously 3674 * fully valid. 3675 */ 3676 if (oldvalid == VM_PAGE_BITS_ALL) 3677 /* 3678 * Perform the pmap_clear_modify() first. Otherwise, 3679 * a concurrent pmap operation, such as 3680 * pmap_protect(), could clear a modification in the 3681 * pmap and set the dirty field on the page before 3682 * pmap_clear_modify() had begun and after the dirty 3683 * field was cleared here. 3684 */ 3685 pmap_clear_modify(m); 3686 m->dirty = 0; 3687 m->oflags &= ~VPO_NOSYNC; 3688 } else if (oldvalid != VM_PAGE_BITS_ALL) 3689 m->dirty &= ~pagebits; 3690 else 3691 vm_page_clear_dirty_mask(m, pagebits); 3692 } 3693 3694 void 3695 vm_page_clear_dirty(vm_page_t m, int base, int size) 3696 { 3697 3698 vm_page_clear_dirty_mask(m, vm_page_bits(base, size)); 3699 } 3700 3701 /* 3702 * vm_page_set_invalid: 3703 * 3704 * Invalidates DEV_BSIZE'd chunks within a page. Both the 3705 * valid and dirty bits for the effected areas are cleared. 3706 */ 3707 void 3708 vm_page_set_invalid(vm_page_t m, int base, int size) 3709 { 3710 vm_page_bits_t bits; 3711 vm_object_t object; 3712 3713 object = m->object; 3714 VM_OBJECT_ASSERT_WLOCKED(object); 3715 if (object->type == OBJT_VNODE && base == 0 && IDX_TO_OFF(m->pindex) + 3716 size >= object->un_pager.vnp.vnp_size) 3717 bits = VM_PAGE_BITS_ALL; 3718 else 3719 bits = vm_page_bits(base, size); 3720 if (object->ref_count != 0 && m->valid == VM_PAGE_BITS_ALL && 3721 bits != 0) 3722 pmap_remove_all(m); 3723 KASSERT((bits == 0 && m->valid == VM_PAGE_BITS_ALL) || 3724 !pmap_page_is_mapped(m), 3725 ("vm_page_set_invalid: page %p is mapped", m)); 3726 m->valid &= ~bits; 3727 m->dirty &= ~bits; 3728 } 3729 3730 /* 3731 * vm_page_zero_invalid() 3732 * 3733 * The kernel assumes that the invalid portions of a page contain 3734 * garbage, but such pages can be mapped into memory by user code. 3735 * When this occurs, we must zero out the non-valid portions of the 3736 * page so user code sees what it expects. 3737 * 3738 * Pages are most often semi-valid when the end of a file is mapped 3739 * into memory and the file's size is not page aligned. 3740 */ 3741 void 3742 vm_page_zero_invalid(vm_page_t m, boolean_t setvalid) 3743 { 3744 int b; 3745 int i; 3746 3747 VM_OBJECT_ASSERT_WLOCKED(m->object); 3748 /* 3749 * Scan the valid bits looking for invalid sections that 3750 * must be zeroed. Invalid sub-DEV_BSIZE'd areas ( where the 3751 * valid bit may be set ) have already been zeroed by 3752 * vm_page_set_validclean(). 3753 */ 3754 for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) { 3755 if (i == (PAGE_SIZE / DEV_BSIZE) || 3756 (m->valid & ((vm_page_bits_t)1 << i))) { 3757 if (i > b) { 3758 pmap_zero_page_area(m, 3759 b << DEV_BSHIFT, (i - b) << DEV_BSHIFT); 3760 } 3761 b = i + 1; 3762 } 3763 } 3764 3765 /* 3766 * setvalid is TRUE when we can safely set the zero'd areas 3767 * as being valid. We can do this if there are no cache consistancy 3768 * issues. e.g. it is ok to do with UFS, but not ok to do with NFS. 3769 */ 3770 if (setvalid) 3771 m->valid = VM_PAGE_BITS_ALL; 3772 } 3773 3774 /* 3775 * vm_page_is_valid: 3776 * 3777 * Is (partial) page valid? Note that the case where size == 0 3778 * will return FALSE in the degenerate case where the page is 3779 * entirely invalid, and TRUE otherwise. 3780 */ 3781 int 3782 vm_page_is_valid(vm_page_t m, int base, int size) 3783 { 3784 vm_page_bits_t bits; 3785 3786 VM_OBJECT_ASSERT_LOCKED(m->object); 3787 bits = vm_page_bits(base, size); 3788 return (m->valid != 0 && (m->valid & bits) == bits); 3789 } 3790 3791 /* 3792 * vm_page_ps_is_valid: 3793 * 3794 * Returns TRUE if the entire (super)page is valid and FALSE otherwise. 3795 */ 3796 boolean_t 3797 vm_page_ps_is_valid(vm_page_t m) 3798 { 3799 int i, npages; 3800 3801 VM_OBJECT_ASSERT_LOCKED(m->object); 3802 npages = atop(pagesizes[m->psind]); 3803 3804 /* 3805 * The physically contiguous pages that make up a superpage, i.e., a 3806 * page with a page size index ("psind") greater than zero, will 3807 * occupy adjacent entries in vm_page_array[]. 3808 */ 3809 for (i = 0; i < npages; i++) { 3810 if (m[i].valid != VM_PAGE_BITS_ALL) 3811 return (FALSE); 3812 } 3813 return (TRUE); 3814 } 3815 3816 /* 3817 * Set the page's dirty bits if the page is modified. 3818 */ 3819 void 3820 vm_page_test_dirty(vm_page_t m) 3821 { 3822 3823 VM_OBJECT_ASSERT_WLOCKED(m->object); 3824 if (m->dirty != VM_PAGE_BITS_ALL && pmap_is_modified(m)) 3825 vm_page_dirty(m); 3826 } 3827 3828 void 3829 vm_page_lock_KBI(vm_page_t m, const char *file, int line) 3830 { 3831 3832 mtx_lock_flags_(vm_page_lockptr(m), 0, file, line); 3833 } 3834 3835 void 3836 vm_page_unlock_KBI(vm_page_t m, const char *file, int line) 3837 { 3838 3839 mtx_unlock_flags_(vm_page_lockptr(m), 0, file, line); 3840 } 3841 3842 int 3843 vm_page_trylock_KBI(vm_page_t m, const char *file, int line) 3844 { 3845 3846 return (mtx_trylock_flags_(vm_page_lockptr(m), 0, file, line)); 3847 } 3848 3849 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT) 3850 void 3851 vm_page_assert_locked_KBI(vm_page_t m, const char *file, int line) 3852 { 3853 3854 vm_page_lock_assert_KBI(m, MA_OWNED, file, line); 3855 } 3856 3857 void 3858 vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line) 3859 { 3860 3861 mtx_assert_(vm_page_lockptr(m), a, file, line); 3862 } 3863 #endif 3864 3865 #ifdef INVARIANTS 3866 void 3867 vm_page_object_lock_assert(vm_page_t m) 3868 { 3869 3870 /* 3871 * Certain of the page's fields may only be modified by the 3872 * holder of the containing object's lock or the exclusive busy. 3873 * holder. Unfortunately, the holder of the write busy is 3874 * not recorded, and thus cannot be checked here. 3875 */ 3876 if (m->object != NULL && !vm_page_xbusied(m)) 3877 VM_OBJECT_ASSERT_WLOCKED(m->object); 3878 } 3879 3880 void 3881 vm_page_assert_pga_writeable(vm_page_t m, uint8_t bits) 3882 { 3883 3884 if ((bits & PGA_WRITEABLE) == 0) 3885 return; 3886 3887 /* 3888 * The PGA_WRITEABLE flag can only be set if the page is 3889 * managed, is exclusively busied or the object is locked. 3890 * Currently, this flag is only set by pmap_enter(). 3891 */ 3892 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 3893 ("PGA_WRITEABLE on unmanaged page")); 3894 if (!vm_page_xbusied(m)) 3895 VM_OBJECT_ASSERT_LOCKED(m->object); 3896 } 3897 #endif 3898 3899 #include "opt_ddb.h" 3900 #ifdef DDB 3901 #include <sys/kernel.h> 3902 3903 #include <ddb/ddb.h> 3904 3905 DB_SHOW_COMMAND(page, vm_page_print_page_info) 3906 { 3907 db_printf("vm_cnt.v_free_count: %d\n", vm_cnt.v_free_count); 3908 db_printf("vm_cnt.v_cache_count: %d\n", vm_cnt.v_cache_count); 3909 db_printf("vm_cnt.v_inactive_count: %d\n", vm_cnt.v_inactive_count); 3910 db_printf("vm_cnt.v_active_count: %d\n", vm_cnt.v_active_count); 3911 db_printf("vm_cnt.v_wire_count: %d\n", vm_cnt.v_wire_count); 3912 db_printf("vm_cnt.v_free_reserved: %d\n", vm_cnt.v_free_reserved); 3913 db_printf("vm_cnt.v_free_min: %d\n", vm_cnt.v_free_min); 3914 db_printf("vm_cnt.v_free_target: %d\n", vm_cnt.v_free_target); 3915 db_printf("vm_cnt.v_inactive_target: %d\n", vm_cnt.v_inactive_target); 3916 } 3917 3918 DB_SHOW_COMMAND(pageq, vm_page_print_pageq_info) 3919 { 3920 int dom; 3921 3922 db_printf("pq_free %d pq_cache %d\n", 3923 vm_cnt.v_free_count, vm_cnt.v_cache_count); 3924 for (dom = 0; dom < vm_ndomains; dom++) { 3925 db_printf( 3926 "dom %d page_cnt %d free %d pq_act %d pq_inact %d pass %d\n", 3927 dom, 3928 vm_dom[dom].vmd_page_count, 3929 vm_dom[dom].vmd_free_count, 3930 vm_dom[dom].vmd_pagequeues[PQ_ACTIVE].pq_cnt, 3931 vm_dom[dom].vmd_pagequeues[PQ_INACTIVE].pq_cnt, 3932 vm_dom[dom].vmd_pass); 3933 } 3934 } 3935 3936 DB_SHOW_COMMAND(pginfo, vm_page_print_pginfo) 3937 { 3938 vm_page_t m; 3939 boolean_t phys; 3940 3941 if (!have_addr) { 3942 db_printf("show pginfo addr\n"); 3943 return; 3944 } 3945 3946 phys = strchr(modif, 'p') != NULL; 3947 if (phys) 3948 m = PHYS_TO_VM_PAGE(addr); 3949 else 3950 m = (vm_page_t)addr; 3951 db_printf( 3952 "page %p obj %p pidx 0x%jx phys 0x%jx q %d hold %d wire %d\n" 3953 " af 0x%x of 0x%x f 0x%x act %d busy %x valid 0x%x dirty 0x%x\n", 3954 m, m->object, (uintmax_t)m->pindex, (uintmax_t)m->phys_addr, 3955 m->queue, m->hold_count, m->wire_count, m->aflags, m->oflags, 3956 m->flags, m->act_count, m->busy_lock, m->valid, m->dirty); 3957 } 3958 #endif /* DDB */ 3959