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/smp.h> 103 #include <sys/sysctl.h> 104 #include <sys/vmmeter.h> 105 #include <sys/vnode.h> 106 107 #include <vm/vm.h> 108 #include <vm/pmap.h> 109 #include <vm/vm_param.h> 110 #include <vm/vm_kern.h> 111 #include <vm/vm_object.h> 112 #include <vm/vm_page.h> 113 #include <vm/vm_pageout.h> 114 #include <vm/vm_pager.h> 115 #include <vm/vm_phys.h> 116 #include <vm/vm_radix.h> 117 #include <vm/vm_reserv.h> 118 #include <vm/vm_extern.h> 119 #include <vm/uma.h> 120 #include <vm/uma_int.h> 121 122 #include <machine/md_var.h> 123 124 /* 125 * Associated with page of user-allocatable memory is a 126 * page structure. 127 */ 128 129 struct vm_domain vm_dom[MAXMEMDOM]; 130 struct mtx_padalign vm_page_queue_free_mtx; 131 132 struct mtx_padalign pa_lock[PA_LOCK_COUNT]; 133 134 vm_page_t vm_page_array; 135 long vm_page_array_size; 136 long first_page; 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 for (i = 0; i < PQ_COUNT; i++) { 398 pq = &vmd->vmd_pagequeues[i]; 399 TAILQ_INIT(&pq->pq_pl); 400 mtx_init(&pq->pq_mutex, pq->pq_name, "vm pagequeue", 401 MTX_DEF | MTX_DUPOK); 402 } 403 } 404 405 /* 406 * vm_page_startup: 407 * 408 * Initializes the resident memory module. 409 * 410 * Allocates memory for the page cells, and 411 * for the object/offset-to-page hash table headers. 412 * Each page cell is initialized and placed on the free list. 413 */ 414 vm_offset_t 415 vm_page_startup(vm_offset_t vaddr) 416 { 417 vm_offset_t mapped; 418 vm_paddr_t page_range; 419 vm_paddr_t new_end; 420 int i; 421 vm_paddr_t pa; 422 vm_paddr_t last_pa; 423 char *list, *listend; 424 vm_paddr_t end; 425 vm_paddr_t biggestsize; 426 vm_paddr_t low_water, high_water; 427 int biggestone; 428 int pages_per_zone; 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 * Almost all of the pages needed for boot strapping UMA are used 474 * for zone structures, so if the number of CPUs results in those 475 * structures taking more than one page each, we set aside more pages 476 * in proportion to the zone structure size. 477 */ 478 pages_per_zone = howmany(sizeof(struct uma_zone) + 479 sizeof(struct uma_cache) * (mp_maxid + 1), UMA_SLAB_SIZE); 480 if (pages_per_zone > 1) { 481 /* Reserve more pages so that we don't run out. */ 482 boot_pages = UMA_BOOT_PAGES_ZONES * pages_per_zone; 483 } 484 485 /* 486 * Allocate memory for use when boot strapping the kernel memory 487 * allocator. 488 * 489 * CTFLAG_RDTUN doesn't work during the early boot process, so we must 490 * manually fetch the value. 491 */ 492 TUNABLE_INT_FETCH("vm.boot_pages", &boot_pages); 493 new_end = end - (boot_pages * UMA_SLAB_SIZE); 494 new_end = trunc_page(new_end); 495 mapped = pmap_map(&vaddr, new_end, end, 496 VM_PROT_READ | VM_PROT_WRITE); 497 bzero((void *)mapped, end - new_end); 498 uma_startup((void *)mapped, boot_pages); 499 500 #if defined(__aarch64__) || defined(__amd64__) || defined(__arm__) || \ 501 defined(__i386__) || defined(__mips__) 502 /* 503 * Allocate a bitmap to indicate that a random physical page 504 * needs to be included in a minidump. 505 * 506 * The amd64 port needs this to indicate which direct map pages 507 * need to be dumped, via calls to dump_add_page()/dump_drop_page(). 508 * 509 * However, i386 still needs this workspace internally within the 510 * minidump code. In theory, they are not needed on i386, but are 511 * included should the sf_buf code decide to use them. 512 */ 513 last_pa = 0; 514 for (i = 0; dump_avail[i + 1] != 0; i += 2) 515 if (dump_avail[i + 1] > last_pa) 516 last_pa = dump_avail[i + 1]; 517 page_range = last_pa / PAGE_SIZE; 518 vm_page_dump_size = round_page(roundup2(page_range, NBBY) / NBBY); 519 new_end -= vm_page_dump_size; 520 vm_page_dump = (void *)(uintptr_t)pmap_map(&vaddr, new_end, 521 new_end + vm_page_dump_size, VM_PROT_READ | VM_PROT_WRITE); 522 bzero((void *)vm_page_dump, vm_page_dump_size); 523 #endif 524 #ifdef __amd64__ 525 /* 526 * Request that the physical pages underlying the message buffer be 527 * included in a crash dump. Since the message buffer is accessed 528 * through the direct map, they are not automatically included. 529 */ 530 pa = DMAP_TO_PHYS((vm_offset_t)msgbufp->msg_ptr); 531 last_pa = pa + round_page(msgbufsize); 532 while (pa < last_pa) { 533 dump_add_page(pa); 534 pa += PAGE_SIZE; 535 } 536 #endif 537 /* 538 * Compute the number of pages of memory that will be available for 539 * use (taking into account the overhead of a page structure per 540 * page). 541 */ 542 first_page = low_water / PAGE_SIZE; 543 #ifdef VM_PHYSSEG_SPARSE 544 page_range = 0; 545 for (i = 0; i < vm_phys_nsegs; i++) { 546 page_range += atop(vm_phys_segs[i].end - 547 vm_phys_segs[i].start); 548 } 549 for (i = 0; phys_avail[i + 1] != 0; i += 2) 550 page_range += atop(phys_avail[i + 1] - phys_avail[i]); 551 #elif defined(VM_PHYSSEG_DENSE) 552 page_range = high_water / PAGE_SIZE - first_page; 553 #else 554 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." 555 #endif 556 end = new_end; 557 558 /* 559 * Reserve an unmapped guard page to trap access to vm_page_array[-1]. 560 */ 561 vaddr += PAGE_SIZE; 562 563 /* 564 * Initialize the mem entry structures now, and put them in the free 565 * queue. 566 */ 567 new_end = trunc_page(end - page_range * sizeof(struct vm_page)); 568 mapped = pmap_map(&vaddr, new_end, end, 569 VM_PROT_READ | VM_PROT_WRITE); 570 vm_page_array = (vm_page_t) mapped; 571 #if VM_NRESERVLEVEL > 0 572 /* 573 * Allocate memory for the reservation management system's data 574 * structures. 575 */ 576 new_end = vm_reserv_startup(&vaddr, new_end, high_water); 577 #endif 578 #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) 579 /* 580 * pmap_map on arm64, amd64, and mips can come out of the direct-map, 581 * not kvm like i386, so the pages must be tracked for a crashdump to 582 * include this data. This includes the vm_page_array and the early 583 * UMA bootstrap pages. 584 */ 585 for (pa = new_end; pa < phys_avail[biggestone + 1]; pa += PAGE_SIZE) 586 dump_add_page(pa); 587 #endif 588 phys_avail[biggestone + 1] = new_end; 589 590 /* 591 * Add physical memory segments corresponding to the available 592 * physical pages. 593 */ 594 for (i = 0; phys_avail[i + 1] != 0; i += 2) 595 vm_phys_add_seg(phys_avail[i], phys_avail[i + 1]); 596 597 /* 598 * Clear all of the page structures 599 */ 600 bzero((caddr_t) vm_page_array, page_range * sizeof(struct vm_page)); 601 for (i = 0; i < page_range; i++) 602 vm_page_array[i].order = VM_NFREEORDER; 603 vm_page_array_size = page_range; 604 605 /* 606 * Initialize the physical memory allocator. 607 */ 608 vm_phys_init(); 609 610 /* 611 * Add every available physical page that is not blacklisted to 612 * the free lists. 613 */ 614 vm_cnt.v_page_count = 0; 615 vm_cnt.v_free_count = 0; 616 for (i = 0; phys_avail[i + 1] != 0; i += 2) { 617 pa = phys_avail[i]; 618 last_pa = phys_avail[i + 1]; 619 while (pa < last_pa) { 620 vm_phys_add_page(pa); 621 pa += PAGE_SIZE; 622 } 623 } 624 625 TAILQ_INIT(&blacklist_head); 626 vm_page_blacklist_load(&list, &listend); 627 vm_page_blacklist_check(list, listend); 628 629 list = kern_getenv("vm.blacklist"); 630 vm_page_blacklist_check(list, NULL); 631 632 freeenv(list); 633 #if VM_NRESERVLEVEL > 0 634 /* 635 * Initialize the reservation management system. 636 */ 637 vm_reserv_init(); 638 #endif 639 return (vaddr); 640 } 641 642 void 643 vm_page_reference(vm_page_t m) 644 { 645 646 vm_page_aflag_set(m, PGA_REFERENCED); 647 } 648 649 /* 650 * vm_page_busy_downgrade: 651 * 652 * Downgrade an exclusive busy page into a single shared busy page. 653 */ 654 void 655 vm_page_busy_downgrade(vm_page_t m) 656 { 657 u_int x; 658 bool locked; 659 660 vm_page_assert_xbusied(m); 661 locked = mtx_owned(vm_page_lockptr(m)); 662 663 for (;;) { 664 x = m->busy_lock; 665 x &= VPB_BIT_WAITERS; 666 if (x != 0 && !locked) 667 vm_page_lock(m); 668 if (atomic_cmpset_rel_int(&m->busy_lock, 669 VPB_SINGLE_EXCLUSIVER | x, VPB_SHARERS_WORD(1))) 670 break; 671 if (x != 0 && !locked) 672 vm_page_unlock(m); 673 } 674 if (x != 0) { 675 wakeup(m); 676 if (!locked) 677 vm_page_unlock(m); 678 } 679 } 680 681 /* 682 * vm_page_sbusied: 683 * 684 * Return a positive value if the page is shared busied, 0 otherwise. 685 */ 686 int 687 vm_page_sbusied(vm_page_t m) 688 { 689 u_int x; 690 691 x = m->busy_lock; 692 return ((x & VPB_BIT_SHARED) != 0 && x != VPB_UNBUSIED); 693 } 694 695 /* 696 * vm_page_sunbusy: 697 * 698 * Shared unbusy a page. 699 */ 700 void 701 vm_page_sunbusy(vm_page_t m) 702 { 703 u_int x; 704 705 vm_page_assert_sbusied(m); 706 707 for (;;) { 708 x = m->busy_lock; 709 if (VPB_SHARERS(x) > 1) { 710 if (atomic_cmpset_int(&m->busy_lock, x, 711 x - VPB_ONE_SHARER)) 712 break; 713 continue; 714 } 715 if ((x & VPB_BIT_WAITERS) == 0) { 716 KASSERT(x == VPB_SHARERS_WORD(1), 717 ("vm_page_sunbusy: invalid lock state")); 718 if (atomic_cmpset_int(&m->busy_lock, 719 VPB_SHARERS_WORD(1), VPB_UNBUSIED)) 720 break; 721 continue; 722 } 723 KASSERT(x == (VPB_SHARERS_WORD(1) | VPB_BIT_WAITERS), 724 ("vm_page_sunbusy: invalid lock state for waiters")); 725 726 vm_page_lock(m); 727 if (!atomic_cmpset_int(&m->busy_lock, x, VPB_UNBUSIED)) { 728 vm_page_unlock(m); 729 continue; 730 } 731 wakeup(m); 732 vm_page_unlock(m); 733 break; 734 } 735 } 736 737 /* 738 * vm_page_busy_sleep: 739 * 740 * Sleep and release the page lock, using the page pointer as wchan. 741 * This is used to implement the hard-path of busying mechanism. 742 * 743 * The given page must be locked. 744 * 745 * If nonshared is true, sleep only if the page is xbusy. 746 */ 747 void 748 vm_page_busy_sleep(vm_page_t m, const char *wmesg, bool nonshared) 749 { 750 u_int x; 751 752 vm_page_assert_locked(m); 753 754 x = m->busy_lock; 755 if (x == VPB_UNBUSIED || (nonshared && (x & VPB_BIT_SHARED) != 0) || 756 ((x & VPB_BIT_WAITERS) == 0 && 757 !atomic_cmpset_int(&m->busy_lock, x, x | VPB_BIT_WAITERS))) { 758 vm_page_unlock(m); 759 return; 760 } 761 msleep(m, vm_page_lockptr(m), PVM | PDROP, wmesg, 0); 762 } 763 764 /* 765 * vm_page_trysbusy: 766 * 767 * Try to shared busy a page. 768 * If the operation succeeds 1 is returned otherwise 0. 769 * The operation never sleeps. 770 */ 771 int 772 vm_page_trysbusy(vm_page_t m) 773 { 774 u_int x; 775 776 for (;;) { 777 x = m->busy_lock; 778 if ((x & VPB_BIT_SHARED) == 0) 779 return (0); 780 if (atomic_cmpset_acq_int(&m->busy_lock, x, x + VPB_ONE_SHARER)) 781 return (1); 782 } 783 } 784 785 static void 786 vm_page_xunbusy_locked(vm_page_t m) 787 { 788 789 vm_page_assert_xbusied(m); 790 vm_page_assert_locked(m); 791 792 atomic_store_rel_int(&m->busy_lock, VPB_UNBUSIED); 793 /* There is a waiter, do wakeup() instead of vm_page_flash(). */ 794 wakeup(m); 795 } 796 797 void 798 vm_page_xunbusy_maybelocked(vm_page_t m) 799 { 800 bool lockacq; 801 802 vm_page_assert_xbusied(m); 803 804 /* 805 * Fast path for unbusy. If it succeeds, we know that there 806 * are no waiters, so we do not need a wakeup. 807 */ 808 if (atomic_cmpset_rel_int(&m->busy_lock, VPB_SINGLE_EXCLUSIVER, 809 VPB_UNBUSIED)) 810 return; 811 812 lockacq = !mtx_owned(vm_page_lockptr(m)); 813 if (lockacq) 814 vm_page_lock(m); 815 vm_page_xunbusy_locked(m); 816 if (lockacq) 817 vm_page_unlock(m); 818 } 819 820 /* 821 * vm_page_xunbusy_hard: 822 * 823 * Called after the first try the exclusive unbusy of a page failed. 824 * It is assumed that the waiters bit is on. 825 */ 826 void 827 vm_page_xunbusy_hard(vm_page_t m) 828 { 829 830 vm_page_assert_xbusied(m); 831 832 vm_page_lock(m); 833 vm_page_xunbusy_locked(m); 834 vm_page_unlock(m); 835 } 836 837 /* 838 * vm_page_flash: 839 * 840 * Wakeup anyone waiting for the page. 841 * The ownership bits do not change. 842 * 843 * The given page must be locked. 844 */ 845 void 846 vm_page_flash(vm_page_t m) 847 { 848 u_int x; 849 850 vm_page_lock_assert(m, MA_OWNED); 851 852 for (;;) { 853 x = m->busy_lock; 854 if ((x & VPB_BIT_WAITERS) == 0) 855 return; 856 if (atomic_cmpset_int(&m->busy_lock, x, 857 x & (~VPB_BIT_WAITERS))) 858 break; 859 } 860 wakeup(m); 861 } 862 863 /* 864 * Keep page from being freed by the page daemon 865 * much of the same effect as wiring, except much lower 866 * overhead and should be used only for *very* temporary 867 * holding ("wiring"). 868 */ 869 void 870 vm_page_hold(vm_page_t mem) 871 { 872 873 vm_page_lock_assert(mem, MA_OWNED); 874 mem->hold_count++; 875 } 876 877 void 878 vm_page_unhold(vm_page_t mem) 879 { 880 881 vm_page_lock_assert(mem, MA_OWNED); 882 KASSERT(mem->hold_count >= 1, ("vm_page_unhold: hold count < 0!!!")); 883 --mem->hold_count; 884 if (mem->hold_count == 0 && (mem->flags & PG_UNHOLDFREE) != 0) 885 vm_page_free_toq(mem); 886 } 887 888 /* 889 * vm_page_unhold_pages: 890 * 891 * Unhold each of the pages that is referenced by the given array. 892 */ 893 void 894 vm_page_unhold_pages(vm_page_t *ma, int count) 895 { 896 struct mtx *mtx, *new_mtx; 897 898 mtx = NULL; 899 for (; count != 0; count--) { 900 /* 901 * Avoid releasing and reacquiring the same page lock. 902 */ 903 new_mtx = vm_page_lockptr(*ma); 904 if (mtx != new_mtx) { 905 if (mtx != NULL) 906 mtx_unlock(mtx); 907 mtx = new_mtx; 908 mtx_lock(mtx); 909 } 910 vm_page_unhold(*ma); 911 ma++; 912 } 913 if (mtx != NULL) 914 mtx_unlock(mtx); 915 } 916 917 vm_page_t 918 PHYS_TO_VM_PAGE(vm_paddr_t pa) 919 { 920 vm_page_t m; 921 922 #ifdef VM_PHYSSEG_SPARSE 923 m = vm_phys_paddr_to_vm_page(pa); 924 if (m == NULL) 925 m = vm_phys_fictitious_to_vm_page(pa); 926 return (m); 927 #elif defined(VM_PHYSSEG_DENSE) 928 long pi; 929 930 pi = atop(pa); 931 if (pi >= first_page && (pi - first_page) < vm_page_array_size) { 932 m = &vm_page_array[pi - first_page]; 933 return (m); 934 } 935 return (vm_phys_fictitious_to_vm_page(pa)); 936 #else 937 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." 938 #endif 939 } 940 941 /* 942 * vm_page_getfake: 943 * 944 * Create a fictitious page with the specified physical address and 945 * memory attribute. The memory attribute is the only the machine- 946 * dependent aspect of a fictitious page that must be initialized. 947 */ 948 vm_page_t 949 vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr) 950 { 951 vm_page_t m; 952 953 m = uma_zalloc(fakepg_zone, M_WAITOK | M_ZERO); 954 vm_page_initfake(m, paddr, memattr); 955 return (m); 956 } 957 958 void 959 vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) 960 { 961 962 if ((m->flags & PG_FICTITIOUS) != 0) { 963 /* 964 * The page's memattr might have changed since the 965 * previous initialization. Update the pmap to the 966 * new memattr. 967 */ 968 goto memattr; 969 } 970 m->phys_addr = paddr; 971 m->queue = PQ_NONE; 972 /* Fictitious pages don't use "segind". */ 973 m->flags = PG_FICTITIOUS; 974 /* Fictitious pages don't use "order" or "pool". */ 975 m->oflags = VPO_UNMANAGED; 976 m->busy_lock = VPB_SINGLE_EXCLUSIVER; 977 m->wire_count = 1; 978 pmap_page_init(m); 979 memattr: 980 pmap_page_set_memattr(m, memattr); 981 } 982 983 /* 984 * vm_page_putfake: 985 * 986 * Release a fictitious page. 987 */ 988 void 989 vm_page_putfake(vm_page_t m) 990 { 991 992 KASSERT((m->oflags & VPO_UNMANAGED) != 0, ("managed %p", m)); 993 KASSERT((m->flags & PG_FICTITIOUS) != 0, 994 ("vm_page_putfake: bad page %p", m)); 995 uma_zfree(fakepg_zone, m); 996 } 997 998 /* 999 * vm_page_updatefake: 1000 * 1001 * Update the given fictitious page to the specified physical address and 1002 * memory attribute. 1003 */ 1004 void 1005 vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) 1006 { 1007 1008 KASSERT((m->flags & PG_FICTITIOUS) != 0, 1009 ("vm_page_updatefake: bad page %p", m)); 1010 m->phys_addr = paddr; 1011 pmap_page_set_memattr(m, memattr); 1012 } 1013 1014 /* 1015 * vm_page_free: 1016 * 1017 * Free a page. 1018 */ 1019 void 1020 vm_page_free(vm_page_t m) 1021 { 1022 1023 m->flags &= ~PG_ZERO; 1024 vm_page_free_toq(m); 1025 } 1026 1027 /* 1028 * vm_page_free_zero: 1029 * 1030 * Free a page to the zerod-pages queue 1031 */ 1032 void 1033 vm_page_free_zero(vm_page_t m) 1034 { 1035 1036 m->flags |= PG_ZERO; 1037 vm_page_free_toq(m); 1038 } 1039 1040 /* 1041 * Unbusy and handle the page queueing for a page from a getpages request that 1042 * was optionally read ahead or behind. 1043 */ 1044 void 1045 vm_page_readahead_finish(vm_page_t m) 1046 { 1047 1048 /* We shouldn't put invalid pages on queues. */ 1049 KASSERT(m->valid != 0, ("%s: %p is invalid", __func__, m)); 1050 1051 /* 1052 * Since the page is not the actually needed one, whether it should 1053 * be activated or deactivated is not obvious. Empirical results 1054 * have shown that deactivating the page is usually the best choice, 1055 * unless the page is wanted by another thread. 1056 */ 1057 vm_page_lock(m); 1058 if ((m->busy_lock & VPB_BIT_WAITERS) != 0) 1059 vm_page_activate(m); 1060 else 1061 vm_page_deactivate(m); 1062 vm_page_unlock(m); 1063 vm_page_xunbusy(m); 1064 } 1065 1066 /* 1067 * vm_page_sleep_if_busy: 1068 * 1069 * Sleep and release the page queues lock if the page is busied. 1070 * Returns TRUE if the thread slept. 1071 * 1072 * The given page must be unlocked and object containing it must 1073 * be locked. 1074 */ 1075 int 1076 vm_page_sleep_if_busy(vm_page_t m, const char *msg) 1077 { 1078 vm_object_t obj; 1079 1080 vm_page_lock_assert(m, MA_NOTOWNED); 1081 VM_OBJECT_ASSERT_WLOCKED(m->object); 1082 1083 if (vm_page_busied(m)) { 1084 /* 1085 * The page-specific object must be cached because page 1086 * identity can change during the sleep, causing the 1087 * re-lock of a different object. 1088 * It is assumed that a reference to the object is already 1089 * held by the callers. 1090 */ 1091 obj = m->object; 1092 vm_page_lock(m); 1093 VM_OBJECT_WUNLOCK(obj); 1094 vm_page_busy_sleep(m, msg, false); 1095 VM_OBJECT_WLOCK(obj); 1096 return (TRUE); 1097 } 1098 return (FALSE); 1099 } 1100 1101 /* 1102 * vm_page_dirty_KBI: [ internal use only ] 1103 * 1104 * Set all bits in the page's dirty field. 1105 * 1106 * The object containing the specified page must be locked if the 1107 * call is made from the machine-independent layer. 1108 * 1109 * See vm_page_clear_dirty_mask(). 1110 * 1111 * This function should only be called by vm_page_dirty(). 1112 */ 1113 void 1114 vm_page_dirty_KBI(vm_page_t m) 1115 { 1116 1117 /* These assertions refer to this operation by its public name. */ 1118 KASSERT((m->flags & PG_CACHED) == 0, 1119 ("vm_page_dirty: page in cache!")); 1120 KASSERT(m->valid == VM_PAGE_BITS_ALL, 1121 ("vm_page_dirty: page is invalid!")); 1122 m->dirty = VM_PAGE_BITS_ALL; 1123 } 1124 1125 /* 1126 * vm_page_insert: [ internal use only ] 1127 * 1128 * Inserts the given mem entry into the object and object list. 1129 * 1130 * The object must be locked. 1131 */ 1132 int 1133 vm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex) 1134 { 1135 vm_page_t mpred; 1136 1137 VM_OBJECT_ASSERT_WLOCKED(object); 1138 mpred = vm_radix_lookup_le(&object->rtree, pindex); 1139 return (vm_page_insert_after(m, object, pindex, mpred)); 1140 } 1141 1142 /* 1143 * vm_page_insert_after: 1144 * 1145 * Inserts the page "m" into the specified object at offset "pindex". 1146 * 1147 * The page "mpred" must immediately precede the offset "pindex" within 1148 * the specified object. 1149 * 1150 * The object must be locked. 1151 */ 1152 static int 1153 vm_page_insert_after(vm_page_t m, vm_object_t object, vm_pindex_t pindex, 1154 vm_page_t mpred) 1155 { 1156 vm_page_t msucc; 1157 1158 VM_OBJECT_ASSERT_WLOCKED(object); 1159 KASSERT(m->object == NULL, 1160 ("vm_page_insert_after: page already inserted")); 1161 if (mpred != NULL) { 1162 KASSERT(mpred->object == object, 1163 ("vm_page_insert_after: object doesn't contain mpred")); 1164 KASSERT(mpred->pindex < pindex, 1165 ("vm_page_insert_after: mpred doesn't precede pindex")); 1166 msucc = TAILQ_NEXT(mpred, listq); 1167 } else 1168 msucc = TAILQ_FIRST(&object->memq); 1169 if (msucc != NULL) 1170 KASSERT(msucc->pindex > pindex, 1171 ("vm_page_insert_after: msucc doesn't succeed pindex")); 1172 1173 /* 1174 * Record the object/offset pair in this page 1175 */ 1176 m->object = object; 1177 m->pindex = pindex; 1178 1179 /* 1180 * Now link into the object's ordered list of backed pages. 1181 */ 1182 if (vm_radix_insert(&object->rtree, m)) { 1183 m->object = NULL; 1184 m->pindex = 0; 1185 return (1); 1186 } 1187 vm_page_insert_radixdone(m, object, mpred); 1188 return (0); 1189 } 1190 1191 /* 1192 * vm_page_insert_radixdone: 1193 * 1194 * Complete page "m" insertion into the specified object after the 1195 * radix trie hooking. 1196 * 1197 * The page "mpred" must precede the offset "m->pindex" within the 1198 * specified object. 1199 * 1200 * The object must be locked. 1201 */ 1202 static void 1203 vm_page_insert_radixdone(vm_page_t m, vm_object_t object, vm_page_t mpred) 1204 { 1205 1206 VM_OBJECT_ASSERT_WLOCKED(object); 1207 KASSERT(object != NULL && m->object == object, 1208 ("vm_page_insert_radixdone: page %p has inconsistent object", m)); 1209 if (mpred != NULL) { 1210 KASSERT(mpred->object == object, 1211 ("vm_page_insert_after: object doesn't contain mpred")); 1212 KASSERT(mpred->pindex < m->pindex, 1213 ("vm_page_insert_after: mpred doesn't precede pindex")); 1214 } 1215 1216 if (mpred != NULL) 1217 TAILQ_INSERT_AFTER(&object->memq, mpred, m, listq); 1218 else 1219 TAILQ_INSERT_HEAD(&object->memq, m, listq); 1220 1221 /* 1222 * Show that the object has one more resident page. 1223 */ 1224 object->resident_page_count++; 1225 1226 /* 1227 * Hold the vnode until the last page is released. 1228 */ 1229 if (object->resident_page_count == 1 && object->type == OBJT_VNODE) 1230 vhold(object->handle); 1231 1232 /* 1233 * Since we are inserting a new and possibly dirty page, 1234 * update the object's OBJ_MIGHTBEDIRTY flag. 1235 */ 1236 if (pmap_page_is_write_mapped(m)) 1237 vm_object_set_writeable_dirty(object); 1238 } 1239 1240 /* 1241 * vm_page_remove: 1242 * 1243 * Removes the given mem entry from the object/offset-page 1244 * table and the object page list, but do not invalidate/terminate 1245 * the backing store. 1246 * 1247 * The object must be locked. The page must be locked if it is managed. 1248 */ 1249 void 1250 vm_page_remove(vm_page_t m) 1251 { 1252 vm_object_t object; 1253 1254 if ((m->oflags & VPO_UNMANAGED) == 0) 1255 vm_page_assert_locked(m); 1256 if ((object = m->object) == NULL) 1257 return; 1258 VM_OBJECT_ASSERT_WLOCKED(object); 1259 if (vm_page_xbusied(m)) 1260 vm_page_xunbusy_maybelocked(m); 1261 1262 /* 1263 * Now remove from the object's list of backed pages. 1264 */ 1265 vm_radix_remove(&object->rtree, m->pindex); 1266 TAILQ_REMOVE(&object->memq, m, listq); 1267 1268 /* 1269 * And show that the object has one fewer resident page. 1270 */ 1271 object->resident_page_count--; 1272 1273 /* 1274 * The vnode may now be recycled. 1275 */ 1276 if (object->resident_page_count == 0 && object->type == OBJT_VNODE) 1277 vdrop(object->handle); 1278 1279 m->object = NULL; 1280 } 1281 1282 /* 1283 * vm_page_lookup: 1284 * 1285 * Returns the page associated with the object/offset 1286 * pair specified; if none is found, NULL is returned. 1287 * 1288 * The object must be locked. 1289 */ 1290 vm_page_t 1291 vm_page_lookup(vm_object_t object, vm_pindex_t pindex) 1292 { 1293 1294 VM_OBJECT_ASSERT_LOCKED(object); 1295 return (vm_radix_lookup(&object->rtree, pindex)); 1296 } 1297 1298 /* 1299 * vm_page_find_least: 1300 * 1301 * Returns the page associated with the object with least pindex 1302 * greater than or equal to the parameter pindex, or NULL. 1303 * 1304 * The object must be locked. 1305 */ 1306 vm_page_t 1307 vm_page_find_least(vm_object_t object, vm_pindex_t pindex) 1308 { 1309 vm_page_t m; 1310 1311 VM_OBJECT_ASSERT_LOCKED(object); 1312 if ((m = TAILQ_FIRST(&object->memq)) != NULL && m->pindex < pindex) 1313 m = vm_radix_lookup_ge(&object->rtree, pindex); 1314 return (m); 1315 } 1316 1317 /* 1318 * Returns the given page's successor (by pindex) within the object if it is 1319 * resident; if none is found, NULL is returned. 1320 * 1321 * The object must be locked. 1322 */ 1323 vm_page_t 1324 vm_page_next(vm_page_t m) 1325 { 1326 vm_page_t next; 1327 1328 VM_OBJECT_ASSERT_LOCKED(m->object); 1329 if ((next = TAILQ_NEXT(m, listq)) != NULL && 1330 next->pindex != m->pindex + 1) 1331 next = NULL; 1332 return (next); 1333 } 1334 1335 /* 1336 * Returns the given page's predecessor (by pindex) within the object if it is 1337 * resident; if none is found, NULL is returned. 1338 * 1339 * The object must be locked. 1340 */ 1341 vm_page_t 1342 vm_page_prev(vm_page_t m) 1343 { 1344 vm_page_t prev; 1345 1346 VM_OBJECT_ASSERT_LOCKED(m->object); 1347 if ((prev = TAILQ_PREV(m, pglist, listq)) != NULL && 1348 prev->pindex != m->pindex - 1) 1349 prev = NULL; 1350 return (prev); 1351 } 1352 1353 /* 1354 * Uses the page mnew as a replacement for an existing page at index 1355 * pindex which must be already present in the object. 1356 * 1357 * The existing page must not be on a paging queue. 1358 */ 1359 vm_page_t 1360 vm_page_replace(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex) 1361 { 1362 vm_page_t mold; 1363 1364 VM_OBJECT_ASSERT_WLOCKED(object); 1365 KASSERT(mnew->object == NULL, 1366 ("vm_page_replace: page already in object")); 1367 1368 /* 1369 * This function mostly follows vm_page_insert() and 1370 * vm_page_remove() without the radix, object count and vnode 1371 * dance. Double check such functions for more comments. 1372 */ 1373 1374 mnew->object = object; 1375 mnew->pindex = pindex; 1376 mold = vm_radix_replace(&object->rtree, mnew); 1377 KASSERT(mold->queue == PQ_NONE, 1378 ("vm_page_replace: mold is on a paging queue")); 1379 1380 /* Keep the resident page list in sorted order. */ 1381 TAILQ_INSERT_AFTER(&object->memq, mold, mnew, listq); 1382 TAILQ_REMOVE(&object->memq, mold, listq); 1383 1384 mold->object = NULL; 1385 vm_page_xunbusy_maybelocked(mold); 1386 1387 /* 1388 * The object's resident_page_count does not change because we have 1389 * swapped one page for another, but OBJ_MIGHTBEDIRTY. 1390 */ 1391 if (pmap_page_is_write_mapped(mnew)) 1392 vm_object_set_writeable_dirty(object); 1393 return (mold); 1394 } 1395 1396 /* 1397 * vm_page_rename: 1398 * 1399 * Move the given memory entry from its 1400 * current object to the specified target object/offset. 1401 * 1402 * Note: swap associated with the page must be invalidated by the move. We 1403 * have to do this for several reasons: (1) we aren't freeing the 1404 * page, (2) we are dirtying the page, (3) the VM system is probably 1405 * moving the page from object A to B, and will then later move 1406 * the backing store from A to B and we can't have a conflict. 1407 * 1408 * Note: we *always* dirty the page. It is necessary both for the 1409 * fact that we moved it, and because we may be invalidating 1410 * swap. If the page is on the cache, we have to deactivate it 1411 * or vm_page_dirty() will panic. Dirty pages are not allowed 1412 * on the cache. 1413 * 1414 * The objects must be locked. 1415 */ 1416 int 1417 vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex) 1418 { 1419 vm_page_t mpred; 1420 vm_pindex_t opidx; 1421 1422 VM_OBJECT_ASSERT_WLOCKED(new_object); 1423 1424 mpred = vm_radix_lookup_le(&new_object->rtree, new_pindex); 1425 KASSERT(mpred == NULL || mpred->pindex != new_pindex, 1426 ("vm_page_rename: pindex already renamed")); 1427 1428 /* 1429 * Create a custom version of vm_page_insert() which does not depend 1430 * by m_prev and can cheat on the implementation aspects of the 1431 * function. 1432 */ 1433 opidx = m->pindex; 1434 m->pindex = new_pindex; 1435 if (vm_radix_insert(&new_object->rtree, m)) { 1436 m->pindex = opidx; 1437 return (1); 1438 } 1439 1440 /* 1441 * The operation cannot fail anymore. The removal must happen before 1442 * the listq iterator is tainted. 1443 */ 1444 m->pindex = opidx; 1445 vm_page_lock(m); 1446 vm_page_remove(m); 1447 1448 /* Return back to the new pindex to complete vm_page_insert(). */ 1449 m->pindex = new_pindex; 1450 m->object = new_object; 1451 vm_page_unlock(m); 1452 vm_page_insert_radixdone(m, new_object, mpred); 1453 vm_page_dirty(m); 1454 return (0); 1455 } 1456 1457 /* 1458 * Convert all of the given object's cached pages that have a 1459 * pindex within the given range into free pages. If the value 1460 * zero is given for "end", then the range's upper bound is 1461 * infinity. If the given object is backed by a vnode and it 1462 * transitions from having one or more cached pages to none, the 1463 * vnode's hold count is reduced. 1464 */ 1465 void 1466 vm_page_cache_free(vm_object_t object, vm_pindex_t start, vm_pindex_t end) 1467 { 1468 vm_page_t m; 1469 boolean_t empty; 1470 1471 mtx_lock(&vm_page_queue_free_mtx); 1472 if (__predict_false(vm_radix_is_empty(&object->cache))) { 1473 mtx_unlock(&vm_page_queue_free_mtx); 1474 return; 1475 } 1476 while ((m = vm_radix_lookup_ge(&object->cache, start)) != NULL) { 1477 if (end != 0 && m->pindex >= end) 1478 break; 1479 vm_radix_remove(&object->cache, m->pindex); 1480 vm_page_cache_turn_free(m); 1481 } 1482 empty = vm_radix_is_empty(&object->cache); 1483 mtx_unlock(&vm_page_queue_free_mtx); 1484 if (object->type == OBJT_VNODE && empty) 1485 vdrop(object->handle); 1486 } 1487 1488 /* 1489 * Returns the cached page that is associated with the given 1490 * object and offset. If, however, none exists, returns NULL. 1491 * 1492 * The free page queue must be locked. 1493 */ 1494 static inline vm_page_t 1495 vm_page_cache_lookup(vm_object_t object, vm_pindex_t pindex) 1496 { 1497 1498 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 1499 return (vm_radix_lookup(&object->cache, pindex)); 1500 } 1501 1502 /* 1503 * Remove the given cached page from its containing object's 1504 * collection of cached pages. 1505 * 1506 * The free page queue must be locked. 1507 */ 1508 static void 1509 vm_page_cache_remove(vm_page_t m) 1510 { 1511 1512 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 1513 KASSERT((m->flags & PG_CACHED) != 0, 1514 ("vm_page_cache_remove: page %p is not cached", m)); 1515 vm_radix_remove(&m->object->cache, m->pindex); 1516 m->object = NULL; 1517 vm_cnt.v_cache_count--; 1518 } 1519 1520 /* 1521 * Transfer all of the cached pages with offset greater than or 1522 * equal to 'offidxstart' from the original object's cache to the 1523 * new object's cache. However, any cached pages with offset 1524 * greater than or equal to the new object's size are kept in the 1525 * original object. Initially, the new object's cache must be 1526 * empty. Offset 'offidxstart' in the original object must 1527 * correspond to offset zero in the new object. 1528 * 1529 * The new object must be locked. 1530 */ 1531 void 1532 vm_page_cache_transfer(vm_object_t orig_object, vm_pindex_t offidxstart, 1533 vm_object_t new_object) 1534 { 1535 vm_page_t m; 1536 1537 /* 1538 * Insertion into an object's collection of cached pages 1539 * requires the object to be locked. In contrast, removal does 1540 * not. 1541 */ 1542 VM_OBJECT_ASSERT_WLOCKED(new_object); 1543 KASSERT(vm_radix_is_empty(&new_object->cache), 1544 ("vm_page_cache_transfer: object %p has cached pages", 1545 new_object)); 1546 mtx_lock(&vm_page_queue_free_mtx); 1547 while ((m = vm_radix_lookup_ge(&orig_object->cache, 1548 offidxstart)) != NULL) { 1549 /* 1550 * Transfer all of the pages with offset greater than or 1551 * equal to 'offidxstart' from the original object's 1552 * cache to the new object's cache. 1553 */ 1554 if ((m->pindex - offidxstart) >= new_object->size) 1555 break; 1556 vm_radix_remove(&orig_object->cache, m->pindex); 1557 /* Update the page's object and offset. */ 1558 m->object = new_object; 1559 m->pindex -= offidxstart; 1560 if (vm_radix_insert(&new_object->cache, m)) 1561 vm_page_cache_turn_free(m); 1562 } 1563 mtx_unlock(&vm_page_queue_free_mtx); 1564 } 1565 1566 /* 1567 * Returns TRUE if a cached page is associated with the given object and 1568 * offset, and FALSE otherwise. 1569 * 1570 * The object must be locked. 1571 */ 1572 boolean_t 1573 vm_page_is_cached(vm_object_t object, vm_pindex_t pindex) 1574 { 1575 vm_page_t m; 1576 1577 /* 1578 * Insertion into an object's collection of cached pages requires the 1579 * object to be locked. Therefore, if the object is locked and the 1580 * object's collection is empty, there is no need to acquire the free 1581 * page queues lock in order to prove that the specified page doesn't 1582 * exist. 1583 */ 1584 VM_OBJECT_ASSERT_WLOCKED(object); 1585 if (__predict_true(vm_object_cache_is_empty(object))) 1586 return (FALSE); 1587 mtx_lock(&vm_page_queue_free_mtx); 1588 m = vm_page_cache_lookup(object, pindex); 1589 mtx_unlock(&vm_page_queue_free_mtx); 1590 return (m != NULL); 1591 } 1592 1593 /* 1594 * vm_page_alloc: 1595 * 1596 * Allocate and return a page that is associated with the specified 1597 * object and offset pair. By default, this page is exclusive busied. 1598 * 1599 * The caller must always specify an allocation class. 1600 * 1601 * allocation classes: 1602 * VM_ALLOC_NORMAL normal process request 1603 * VM_ALLOC_SYSTEM system *really* needs a page 1604 * VM_ALLOC_INTERRUPT interrupt time request 1605 * 1606 * optional allocation flags: 1607 * VM_ALLOC_COUNT(number) the number of additional pages that the caller 1608 * intends to allocate 1609 * VM_ALLOC_IFCACHED return page only if it is cached 1610 * VM_ALLOC_IFNOTCACHED return NULL, do not reactivate if the page 1611 * is cached 1612 * VM_ALLOC_NOBUSY do not exclusive busy the page 1613 * VM_ALLOC_NODUMP do not include the page in a kernel core dump 1614 * VM_ALLOC_NOOBJ page is not associated with an object and 1615 * should not be exclusive busy 1616 * VM_ALLOC_SBUSY shared busy the allocated page 1617 * VM_ALLOC_WIRED wire the allocated page 1618 * VM_ALLOC_ZERO prefer a zeroed page 1619 * 1620 * This routine may not sleep. 1621 */ 1622 vm_page_t 1623 vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req) 1624 { 1625 struct vnode *vp = NULL; 1626 vm_object_t m_object; 1627 vm_page_t m, mpred; 1628 int flags, req_class; 1629 1630 mpred = 0; /* XXX: pacify gcc */ 1631 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) && 1632 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) && 1633 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 1634 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 1635 ("vm_page_alloc: inconsistent object(%p)/req(%x)", (void *)object, 1636 req)); 1637 if (object != NULL) 1638 VM_OBJECT_ASSERT_WLOCKED(object); 1639 1640 req_class = req & VM_ALLOC_CLASS_MASK; 1641 1642 /* 1643 * The page daemon is allowed to dig deeper into the free page list. 1644 */ 1645 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 1646 req_class = VM_ALLOC_SYSTEM; 1647 1648 if (object != NULL) { 1649 mpred = vm_radix_lookup_le(&object->rtree, pindex); 1650 KASSERT(mpred == NULL || mpred->pindex != pindex, 1651 ("vm_page_alloc: pindex already allocated")); 1652 } 1653 1654 /* 1655 * The page allocation request can came from consumers which already 1656 * hold the free page queue mutex, like vm_page_insert() in 1657 * vm_page_cache(). 1658 */ 1659 mtx_lock_flags(&vm_page_queue_free_mtx, MTX_RECURSE); 1660 if (vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_free_reserved || 1661 (req_class == VM_ALLOC_SYSTEM && 1662 vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_interrupt_free_min) || 1663 (req_class == VM_ALLOC_INTERRUPT && 1664 vm_cnt.v_free_count + vm_cnt.v_cache_count > 0)) { 1665 /* 1666 * Allocate from the free queue if the number of free pages 1667 * exceeds the minimum for the request class. 1668 */ 1669 if (object != NULL && 1670 (m = vm_page_cache_lookup(object, pindex)) != NULL) { 1671 if ((req & VM_ALLOC_IFNOTCACHED) != 0) { 1672 mtx_unlock(&vm_page_queue_free_mtx); 1673 return (NULL); 1674 } 1675 if (vm_phys_unfree_page(m)) 1676 vm_phys_set_pool(VM_FREEPOOL_DEFAULT, m, 0); 1677 #if VM_NRESERVLEVEL > 0 1678 else if (!vm_reserv_reactivate_page(m)) 1679 #else 1680 else 1681 #endif 1682 panic("vm_page_alloc: cache page %p is missing" 1683 " from the free queue", m); 1684 } else if ((req & VM_ALLOC_IFCACHED) != 0) { 1685 mtx_unlock(&vm_page_queue_free_mtx); 1686 return (NULL); 1687 #if VM_NRESERVLEVEL > 0 1688 } else if (object == NULL || (object->flags & (OBJ_COLORED | 1689 OBJ_FICTITIOUS)) != OBJ_COLORED || (m = 1690 vm_reserv_alloc_page(object, pindex, mpred)) == NULL) { 1691 #else 1692 } else { 1693 #endif 1694 m = vm_phys_alloc_pages(object != NULL ? 1695 VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT, 0); 1696 #if VM_NRESERVLEVEL > 0 1697 if (m == NULL && vm_reserv_reclaim_inactive()) { 1698 m = vm_phys_alloc_pages(object != NULL ? 1699 VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT, 1700 0); 1701 } 1702 #endif 1703 } 1704 } else { 1705 /* 1706 * Not allocatable, give up. 1707 */ 1708 mtx_unlock(&vm_page_queue_free_mtx); 1709 atomic_add_int(&vm_pageout_deficit, 1710 max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1)); 1711 pagedaemon_wakeup(); 1712 return (NULL); 1713 } 1714 1715 /* 1716 * At this point we had better have found a good page. 1717 */ 1718 KASSERT(m != NULL, ("vm_page_alloc: missing page")); 1719 KASSERT(m->queue == PQ_NONE, 1720 ("vm_page_alloc: page %p has unexpected queue %d", m, m->queue)); 1721 KASSERT(m->wire_count == 0, ("vm_page_alloc: page %p is wired", m)); 1722 KASSERT(m->hold_count == 0, ("vm_page_alloc: page %p is held", m)); 1723 KASSERT(!vm_page_busied(m), ("vm_page_alloc: page %p is busy", m)); 1724 KASSERT(m->dirty == 0, ("vm_page_alloc: page %p is dirty", m)); 1725 KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, 1726 ("vm_page_alloc: page %p has unexpected memattr %d", m, 1727 pmap_page_get_memattr(m))); 1728 if ((m->flags & PG_CACHED) != 0) { 1729 KASSERT((m->flags & PG_ZERO) == 0, 1730 ("vm_page_alloc: cached page %p is PG_ZERO", m)); 1731 KASSERT(m->valid != 0, 1732 ("vm_page_alloc: cached page %p is invalid", m)); 1733 if (m->object == object && m->pindex == pindex) 1734 vm_cnt.v_reactivated++; 1735 else 1736 m->valid = 0; 1737 m_object = m->object; 1738 vm_page_cache_remove(m); 1739 if (m_object->type == OBJT_VNODE && 1740 vm_object_cache_is_empty(m_object)) 1741 vp = m_object->handle; 1742 } else { 1743 KASSERT(m->valid == 0, 1744 ("vm_page_alloc: free page %p is valid", m)); 1745 vm_phys_freecnt_adj(m, -1); 1746 } 1747 mtx_unlock(&vm_page_queue_free_mtx); 1748 1749 /* 1750 * Initialize the page. Only the PG_ZERO flag is inherited. 1751 */ 1752 flags = 0; 1753 if ((req & VM_ALLOC_ZERO) != 0) 1754 flags = PG_ZERO; 1755 flags &= m->flags; 1756 if ((req & VM_ALLOC_NODUMP) != 0) 1757 flags |= PG_NODUMP; 1758 m->flags = flags; 1759 m->aflags = 0; 1760 m->oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ? 1761 VPO_UNMANAGED : 0; 1762 m->busy_lock = VPB_UNBUSIED; 1763 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0) 1764 m->busy_lock = VPB_SINGLE_EXCLUSIVER; 1765 if ((req & VM_ALLOC_SBUSY) != 0) 1766 m->busy_lock = VPB_SHARERS_WORD(1); 1767 if (req & VM_ALLOC_WIRED) { 1768 /* 1769 * The page lock is not required for wiring a page until that 1770 * page is inserted into the object. 1771 */ 1772 atomic_add_int(&vm_cnt.v_wire_count, 1); 1773 m->wire_count = 1; 1774 } 1775 m->act_count = 0; 1776 1777 if (object != NULL) { 1778 if (vm_page_insert_after(m, object, pindex, mpred)) { 1779 /* See the comment below about hold count. */ 1780 if (vp != NULL) 1781 vdrop(vp); 1782 pagedaemon_wakeup(); 1783 if (req & VM_ALLOC_WIRED) { 1784 atomic_subtract_int(&vm_cnt.v_wire_count, 1); 1785 m->wire_count = 0; 1786 } 1787 m->object = NULL; 1788 m->oflags = VPO_UNMANAGED; 1789 m->busy_lock = VPB_UNBUSIED; 1790 vm_page_free(m); 1791 return (NULL); 1792 } 1793 1794 /* Ignore device objects; the pager sets "memattr" for them. */ 1795 if (object->memattr != VM_MEMATTR_DEFAULT && 1796 (object->flags & OBJ_FICTITIOUS) == 0) 1797 pmap_page_set_memattr(m, object->memattr); 1798 } else 1799 m->pindex = pindex; 1800 1801 /* 1802 * The following call to vdrop() must come after the above call 1803 * to vm_page_insert() in case both affect the same object and 1804 * vnode. Otherwise, the affected vnode's hold count could 1805 * temporarily become zero. 1806 */ 1807 if (vp != NULL) 1808 vdrop(vp); 1809 1810 /* 1811 * Don't wakeup too often - wakeup the pageout daemon when 1812 * we would be nearly out of memory. 1813 */ 1814 if (vm_paging_needed()) 1815 pagedaemon_wakeup(); 1816 1817 return (m); 1818 } 1819 1820 static void 1821 vm_page_alloc_contig_vdrop(struct spglist *lst) 1822 { 1823 1824 while (!SLIST_EMPTY(lst)) { 1825 vdrop((struct vnode *)SLIST_FIRST(lst)-> plinks.s.pv); 1826 SLIST_REMOVE_HEAD(lst, plinks.s.ss); 1827 } 1828 } 1829 1830 /* 1831 * vm_page_alloc_contig: 1832 * 1833 * Allocate a contiguous set of physical pages of the given size "npages" 1834 * from the free lists. All of the physical pages must be at or above 1835 * the given physical address "low" and below the given physical address 1836 * "high". The given value "alignment" determines the alignment of the 1837 * first physical page in the set. If the given value "boundary" is 1838 * non-zero, then the set of physical pages cannot cross any physical 1839 * address boundary that is a multiple of that value. Both "alignment" 1840 * and "boundary" must be a power of two. 1841 * 1842 * If the specified memory attribute, "memattr", is VM_MEMATTR_DEFAULT, 1843 * then the memory attribute setting for the physical pages is configured 1844 * to the object's memory attribute setting. Otherwise, the memory 1845 * attribute setting for the physical pages is configured to "memattr", 1846 * overriding the object's memory attribute setting. However, if the 1847 * object's memory attribute setting is not VM_MEMATTR_DEFAULT, then the 1848 * memory attribute setting for the physical pages cannot be configured 1849 * to VM_MEMATTR_DEFAULT. 1850 * 1851 * The caller must always specify an allocation class. 1852 * 1853 * allocation classes: 1854 * VM_ALLOC_NORMAL normal process request 1855 * VM_ALLOC_SYSTEM system *really* needs a page 1856 * VM_ALLOC_INTERRUPT interrupt time request 1857 * 1858 * optional allocation flags: 1859 * VM_ALLOC_NOBUSY do not exclusive busy the page 1860 * VM_ALLOC_NODUMP do not include the page in a kernel core dump 1861 * VM_ALLOC_NOOBJ page is not associated with an object and 1862 * should not be exclusive busy 1863 * VM_ALLOC_SBUSY shared busy the allocated page 1864 * VM_ALLOC_WIRED wire the allocated page 1865 * VM_ALLOC_ZERO prefer a zeroed page 1866 * 1867 * This routine may not sleep. 1868 */ 1869 vm_page_t 1870 vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req, 1871 u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, 1872 vm_paddr_t boundary, vm_memattr_t memattr) 1873 { 1874 struct vnode *drop; 1875 struct spglist deferred_vdrop_list; 1876 vm_page_t m, m_tmp, m_ret; 1877 u_int flags; 1878 int req_class; 1879 1880 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) && 1881 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) && 1882 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 1883 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 1884 ("vm_page_alloc: inconsistent object(%p)/req(%x)", (void *)object, 1885 req)); 1886 if (object != NULL) { 1887 VM_OBJECT_ASSERT_WLOCKED(object); 1888 KASSERT(object->type == OBJT_PHYS, 1889 ("vm_page_alloc_contig: object %p isn't OBJT_PHYS", 1890 object)); 1891 } 1892 KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero")); 1893 req_class = req & VM_ALLOC_CLASS_MASK; 1894 1895 /* 1896 * The page daemon is allowed to dig deeper into the free page list. 1897 */ 1898 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 1899 req_class = VM_ALLOC_SYSTEM; 1900 1901 SLIST_INIT(&deferred_vdrop_list); 1902 mtx_lock(&vm_page_queue_free_mtx); 1903 if (vm_cnt.v_free_count + vm_cnt.v_cache_count >= npages + 1904 vm_cnt.v_free_reserved || (req_class == VM_ALLOC_SYSTEM && 1905 vm_cnt.v_free_count + vm_cnt.v_cache_count >= npages + 1906 vm_cnt.v_interrupt_free_min) || (req_class == VM_ALLOC_INTERRUPT && 1907 vm_cnt.v_free_count + vm_cnt.v_cache_count >= npages)) { 1908 #if VM_NRESERVLEVEL > 0 1909 retry: 1910 if (object == NULL || (object->flags & OBJ_COLORED) == 0 || 1911 (m_ret = vm_reserv_alloc_contig(object, pindex, npages, 1912 low, high, alignment, boundary)) == NULL) 1913 #endif 1914 m_ret = vm_phys_alloc_contig(npages, low, high, 1915 alignment, boundary); 1916 } else { 1917 mtx_unlock(&vm_page_queue_free_mtx); 1918 atomic_add_int(&vm_pageout_deficit, npages); 1919 pagedaemon_wakeup(); 1920 return (NULL); 1921 } 1922 if (m_ret != NULL) 1923 for (m = m_ret; m < &m_ret[npages]; m++) { 1924 drop = vm_page_alloc_init(m); 1925 if (drop != NULL) { 1926 /* 1927 * Enqueue the vnode for deferred vdrop(). 1928 */ 1929 m->plinks.s.pv = drop; 1930 SLIST_INSERT_HEAD(&deferred_vdrop_list, m, 1931 plinks.s.ss); 1932 } 1933 } 1934 else { 1935 #if VM_NRESERVLEVEL > 0 1936 if (vm_reserv_reclaim_contig(npages, low, high, alignment, 1937 boundary)) 1938 goto retry; 1939 #endif 1940 } 1941 mtx_unlock(&vm_page_queue_free_mtx); 1942 if (m_ret == NULL) 1943 return (NULL); 1944 1945 /* 1946 * Initialize the pages. Only the PG_ZERO flag is inherited. 1947 */ 1948 flags = 0; 1949 if ((req & VM_ALLOC_ZERO) != 0) 1950 flags = PG_ZERO; 1951 if ((req & VM_ALLOC_NODUMP) != 0) 1952 flags |= PG_NODUMP; 1953 if ((req & VM_ALLOC_WIRED) != 0) 1954 atomic_add_int(&vm_cnt.v_wire_count, npages); 1955 if (object != NULL) { 1956 if (object->memattr != VM_MEMATTR_DEFAULT && 1957 memattr == VM_MEMATTR_DEFAULT) 1958 memattr = object->memattr; 1959 } 1960 for (m = m_ret; m < &m_ret[npages]; m++) { 1961 m->aflags = 0; 1962 m->flags = (m->flags | PG_NODUMP) & flags; 1963 m->busy_lock = VPB_UNBUSIED; 1964 if (object != NULL) { 1965 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0) 1966 m->busy_lock = VPB_SINGLE_EXCLUSIVER; 1967 if ((req & VM_ALLOC_SBUSY) != 0) 1968 m->busy_lock = VPB_SHARERS_WORD(1); 1969 } 1970 if ((req & VM_ALLOC_WIRED) != 0) 1971 m->wire_count = 1; 1972 /* Unmanaged pages don't use "act_count". */ 1973 m->oflags = VPO_UNMANAGED; 1974 if (object != NULL) { 1975 if (vm_page_insert(m, object, pindex)) { 1976 vm_page_alloc_contig_vdrop( 1977 &deferred_vdrop_list); 1978 if (vm_paging_needed()) 1979 pagedaemon_wakeup(); 1980 if ((req & VM_ALLOC_WIRED) != 0) 1981 atomic_subtract_int(&vm_cnt.v_wire_count, 1982 npages); 1983 for (m_tmp = m, m = m_ret; 1984 m < &m_ret[npages]; m++) { 1985 if ((req & VM_ALLOC_WIRED) != 0) 1986 m->wire_count = 0; 1987 if (m >= m_tmp) { 1988 m->object = NULL; 1989 m->oflags |= VPO_UNMANAGED; 1990 } 1991 m->busy_lock = VPB_UNBUSIED; 1992 vm_page_free(m); 1993 } 1994 return (NULL); 1995 } 1996 } else 1997 m->pindex = pindex; 1998 if (memattr != VM_MEMATTR_DEFAULT) 1999 pmap_page_set_memattr(m, memattr); 2000 pindex++; 2001 } 2002 vm_page_alloc_contig_vdrop(&deferred_vdrop_list); 2003 if (vm_paging_needed()) 2004 pagedaemon_wakeup(); 2005 return (m_ret); 2006 } 2007 2008 /* 2009 * Initialize a page that has been freshly dequeued from a freelist. 2010 * The caller has to drop the vnode returned, if it is not NULL. 2011 * 2012 * This function may only be used to initialize unmanaged pages. 2013 * 2014 * To be called with vm_page_queue_free_mtx held. 2015 */ 2016 static struct vnode * 2017 vm_page_alloc_init(vm_page_t m) 2018 { 2019 struct vnode *drop; 2020 vm_object_t m_object; 2021 2022 KASSERT(m->queue == PQ_NONE, 2023 ("vm_page_alloc_init: page %p has unexpected queue %d", 2024 m, m->queue)); 2025 KASSERT(m->wire_count == 0, 2026 ("vm_page_alloc_init: page %p is wired", m)); 2027 KASSERT(m->hold_count == 0, 2028 ("vm_page_alloc_init: page %p is held", m)); 2029 KASSERT(!vm_page_busied(m), 2030 ("vm_page_alloc_init: page %p is busy", m)); 2031 KASSERT(m->dirty == 0, 2032 ("vm_page_alloc_init: page %p is dirty", m)); 2033 KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, 2034 ("vm_page_alloc_init: page %p has unexpected memattr %d", 2035 m, pmap_page_get_memattr(m))); 2036 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 2037 drop = NULL; 2038 if ((m->flags & PG_CACHED) != 0) { 2039 KASSERT((m->flags & PG_ZERO) == 0, 2040 ("vm_page_alloc_init: cached page %p is PG_ZERO", m)); 2041 m->valid = 0; 2042 m_object = m->object; 2043 vm_page_cache_remove(m); 2044 if (m_object->type == OBJT_VNODE && 2045 vm_object_cache_is_empty(m_object)) 2046 drop = m_object->handle; 2047 } else { 2048 KASSERT(m->valid == 0, 2049 ("vm_page_alloc_init: free page %p is valid", m)); 2050 vm_phys_freecnt_adj(m, -1); 2051 } 2052 return (drop); 2053 } 2054 2055 /* 2056 * vm_page_alloc_freelist: 2057 * 2058 * Allocate a physical page from the specified free page list. 2059 * 2060 * The caller must always specify an allocation class. 2061 * 2062 * allocation classes: 2063 * VM_ALLOC_NORMAL normal process request 2064 * VM_ALLOC_SYSTEM system *really* needs a page 2065 * VM_ALLOC_INTERRUPT interrupt time request 2066 * 2067 * optional allocation flags: 2068 * VM_ALLOC_COUNT(number) the number of additional pages that the caller 2069 * intends to allocate 2070 * VM_ALLOC_WIRED wire the allocated page 2071 * VM_ALLOC_ZERO prefer a zeroed page 2072 * 2073 * This routine may not sleep. 2074 */ 2075 vm_page_t 2076 vm_page_alloc_freelist(int flind, int req) 2077 { 2078 struct vnode *drop; 2079 vm_page_t m; 2080 u_int flags; 2081 int req_class; 2082 2083 req_class = req & VM_ALLOC_CLASS_MASK; 2084 2085 /* 2086 * The page daemon is allowed to dig deeper into the free page list. 2087 */ 2088 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 2089 req_class = VM_ALLOC_SYSTEM; 2090 2091 /* 2092 * Do not allocate reserved pages unless the req has asked for it. 2093 */ 2094 mtx_lock_flags(&vm_page_queue_free_mtx, MTX_RECURSE); 2095 if (vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_free_reserved || 2096 (req_class == VM_ALLOC_SYSTEM && 2097 vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_interrupt_free_min) || 2098 (req_class == VM_ALLOC_INTERRUPT && 2099 vm_cnt.v_free_count + vm_cnt.v_cache_count > 0)) 2100 m = vm_phys_alloc_freelist_pages(flind, VM_FREEPOOL_DIRECT, 0); 2101 else { 2102 mtx_unlock(&vm_page_queue_free_mtx); 2103 atomic_add_int(&vm_pageout_deficit, 2104 max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1)); 2105 pagedaemon_wakeup(); 2106 return (NULL); 2107 } 2108 if (m == NULL) { 2109 mtx_unlock(&vm_page_queue_free_mtx); 2110 return (NULL); 2111 } 2112 drop = vm_page_alloc_init(m); 2113 mtx_unlock(&vm_page_queue_free_mtx); 2114 2115 /* 2116 * Initialize the page. Only the PG_ZERO flag is inherited. 2117 */ 2118 m->aflags = 0; 2119 flags = 0; 2120 if ((req & VM_ALLOC_ZERO) != 0) 2121 flags = PG_ZERO; 2122 m->flags &= flags; 2123 if ((req & VM_ALLOC_WIRED) != 0) { 2124 /* 2125 * The page lock is not required for wiring a page that does 2126 * not belong to an object. 2127 */ 2128 atomic_add_int(&vm_cnt.v_wire_count, 1); 2129 m->wire_count = 1; 2130 } 2131 /* Unmanaged pages don't use "act_count". */ 2132 m->oflags = VPO_UNMANAGED; 2133 if (drop != NULL) 2134 vdrop(drop); 2135 if (vm_paging_needed()) 2136 pagedaemon_wakeup(); 2137 return (m); 2138 } 2139 2140 #define VPSC_ANY 0 /* No restrictions. */ 2141 #define VPSC_NORESERV 1 /* Skip reservations; implies VPSC_NOSUPER. */ 2142 #define VPSC_NOSUPER 2 /* Skip superpages. */ 2143 2144 /* 2145 * vm_page_scan_contig: 2146 * 2147 * Scan vm_page_array[] between the specified entries "m_start" and 2148 * "m_end" for a run of contiguous physical pages that satisfy the 2149 * specified conditions, and return the lowest page in the run. The 2150 * specified "alignment" determines the alignment of the lowest physical 2151 * page in the run. If the specified "boundary" is non-zero, then the 2152 * run of physical pages cannot span a physical address that is a 2153 * multiple of "boundary". 2154 * 2155 * "m_end" is never dereferenced, so it need not point to a vm_page 2156 * structure within vm_page_array[]. 2157 * 2158 * "npages" must be greater than zero. "m_start" and "m_end" must not 2159 * span a hole (or discontiguity) in the physical address space. Both 2160 * "alignment" and "boundary" must be a power of two. 2161 */ 2162 vm_page_t 2163 vm_page_scan_contig(u_long npages, vm_page_t m_start, vm_page_t m_end, 2164 u_long alignment, vm_paddr_t boundary, int options) 2165 { 2166 struct mtx *m_mtx, *new_mtx; 2167 vm_object_t object; 2168 vm_paddr_t pa; 2169 vm_page_t m, m_run; 2170 #if VM_NRESERVLEVEL > 0 2171 int level; 2172 #endif 2173 int m_inc, order, run_ext, run_len; 2174 2175 KASSERT(npages > 0, ("npages is 0")); 2176 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 2177 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 2178 m_run = NULL; 2179 run_len = 0; 2180 m_mtx = NULL; 2181 for (m = m_start; m < m_end && run_len < npages; m += m_inc) { 2182 KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0, 2183 ("page %p is PG_FICTITIOUS or PG_MARKER", m)); 2184 2185 /* 2186 * If the current page would be the start of a run, check its 2187 * physical address against the end, alignment, and boundary 2188 * conditions. If it doesn't satisfy these conditions, either 2189 * terminate the scan or advance to the next page that 2190 * satisfies the failed condition. 2191 */ 2192 if (run_len == 0) { 2193 KASSERT(m_run == NULL, ("m_run != NULL")); 2194 if (m + npages > m_end) 2195 break; 2196 pa = VM_PAGE_TO_PHYS(m); 2197 if ((pa & (alignment - 1)) != 0) { 2198 m_inc = atop(roundup2(pa, alignment) - pa); 2199 continue; 2200 } 2201 if (rounddown2(pa ^ (pa + ptoa(npages) - 1), 2202 boundary) != 0) { 2203 m_inc = atop(roundup2(pa, boundary) - pa); 2204 continue; 2205 } 2206 } else 2207 KASSERT(m_run != NULL, ("m_run == NULL")); 2208 2209 /* 2210 * Avoid releasing and reacquiring the same page lock. 2211 */ 2212 new_mtx = vm_page_lockptr(m); 2213 if (m_mtx != new_mtx) { 2214 if (m_mtx != NULL) 2215 mtx_unlock(m_mtx); 2216 m_mtx = new_mtx; 2217 mtx_lock(m_mtx); 2218 } 2219 m_inc = 1; 2220 retry: 2221 if (m->wire_count != 0 || m->hold_count != 0) 2222 run_ext = 0; 2223 #if VM_NRESERVLEVEL > 0 2224 else if ((level = vm_reserv_level(m)) >= 0 && 2225 (options & VPSC_NORESERV) != 0) { 2226 run_ext = 0; 2227 /* Advance to the end of the reservation. */ 2228 pa = VM_PAGE_TO_PHYS(m); 2229 m_inc = atop(roundup2(pa + 1, vm_reserv_size(level)) - 2230 pa); 2231 } 2232 #endif 2233 else if ((object = m->object) != NULL) { 2234 /* 2235 * The page is considered eligible for relocation if 2236 * and only if it could be laundered or reclaimed by 2237 * the page daemon. 2238 */ 2239 if (!VM_OBJECT_TRYRLOCK(object)) { 2240 mtx_unlock(m_mtx); 2241 VM_OBJECT_RLOCK(object); 2242 mtx_lock(m_mtx); 2243 if (m->object != object) { 2244 /* 2245 * The page may have been freed. 2246 */ 2247 VM_OBJECT_RUNLOCK(object); 2248 goto retry; 2249 } else if (m->wire_count != 0 || 2250 m->hold_count != 0) { 2251 run_ext = 0; 2252 goto unlock; 2253 } 2254 } 2255 KASSERT((m->flags & PG_UNHOLDFREE) == 0, 2256 ("page %p is PG_UNHOLDFREE", m)); 2257 /* Don't care: PG_NODUMP, PG_WINATCFLS, PG_ZERO. */ 2258 if (object->type != OBJT_DEFAULT && 2259 object->type != OBJT_SWAP && 2260 object->type != OBJT_VNODE) 2261 run_ext = 0; 2262 else if ((m->flags & PG_CACHED) != 0 || 2263 m != vm_page_lookup(object, m->pindex)) { 2264 /* 2265 * The page is cached or recently converted 2266 * from cached to free. 2267 */ 2268 #if VM_NRESERVLEVEL > 0 2269 if (level >= 0) { 2270 /* 2271 * The page is reserved. Extend the 2272 * current run by one page. 2273 */ 2274 run_ext = 1; 2275 } else 2276 #endif 2277 if ((order = m->order) < VM_NFREEORDER) { 2278 /* 2279 * The page is enqueued in the 2280 * physical memory allocator's cache/ 2281 * free page queues. Moreover, it is 2282 * the first page in a power-of-two- 2283 * sized run of contiguous cache/free 2284 * pages. Add these pages to the end 2285 * of the current run, and jump 2286 * ahead. 2287 */ 2288 run_ext = 1 << order; 2289 m_inc = 1 << order; 2290 } else 2291 run_ext = 0; 2292 #if VM_NRESERVLEVEL > 0 2293 } else if ((options & VPSC_NOSUPER) != 0 && 2294 (level = vm_reserv_level_iffullpop(m)) >= 0) { 2295 run_ext = 0; 2296 /* Advance to the end of the superpage. */ 2297 pa = VM_PAGE_TO_PHYS(m); 2298 m_inc = atop(roundup2(pa + 1, 2299 vm_reserv_size(level)) - pa); 2300 #endif 2301 } else if (object->memattr == VM_MEMATTR_DEFAULT && 2302 m->queue != PQ_NONE && !vm_page_busied(m)) { 2303 /* 2304 * The page is allocated but eligible for 2305 * relocation. Extend the current run by one 2306 * page. 2307 */ 2308 KASSERT(pmap_page_get_memattr(m) == 2309 VM_MEMATTR_DEFAULT, 2310 ("page %p has an unexpected memattr", m)); 2311 KASSERT((m->oflags & (VPO_SWAPINPROG | 2312 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, 2313 ("page %p has unexpected oflags", m)); 2314 /* Don't care: VPO_NOSYNC. */ 2315 run_ext = 1; 2316 } else 2317 run_ext = 0; 2318 unlock: 2319 VM_OBJECT_RUNLOCK(object); 2320 #if VM_NRESERVLEVEL > 0 2321 } else if (level >= 0) { 2322 /* 2323 * The page is reserved but not yet allocated. In 2324 * other words, it is still cached or free. Extend 2325 * the current run by one page. 2326 */ 2327 run_ext = 1; 2328 #endif 2329 } else if ((order = m->order) < VM_NFREEORDER) { 2330 /* 2331 * The page is enqueued in the physical memory 2332 * allocator's cache/free page queues. Moreover, it 2333 * is the first page in a power-of-two-sized run of 2334 * contiguous cache/free pages. Add these pages to 2335 * the end of the current run, and jump ahead. 2336 */ 2337 run_ext = 1 << order; 2338 m_inc = 1 << order; 2339 } else { 2340 /* 2341 * Skip the page for one of the following reasons: (1) 2342 * It is enqueued in the physical memory allocator's 2343 * cache/free page queues. However, it is not the 2344 * first page in a run of contiguous cache/free pages. 2345 * (This case rarely occurs because the scan is 2346 * performed in ascending order.) (2) It is not 2347 * reserved, and it is transitioning from free to 2348 * allocated. (Conversely, the transition from 2349 * allocated to free for managed pages is blocked by 2350 * the page lock.) (3) It is allocated but not 2351 * contained by an object and not wired, e.g., 2352 * allocated by Xen's balloon driver. 2353 */ 2354 run_ext = 0; 2355 } 2356 2357 /* 2358 * Extend or reset the current run of pages. 2359 */ 2360 if (run_ext > 0) { 2361 if (run_len == 0) 2362 m_run = m; 2363 run_len += run_ext; 2364 } else { 2365 if (run_len > 0) { 2366 m_run = NULL; 2367 run_len = 0; 2368 } 2369 } 2370 } 2371 if (m_mtx != NULL) 2372 mtx_unlock(m_mtx); 2373 if (run_len >= npages) 2374 return (m_run); 2375 return (NULL); 2376 } 2377 2378 /* 2379 * vm_page_reclaim_run: 2380 * 2381 * Try to relocate each of the allocated virtual pages within the 2382 * specified run of physical pages to a new physical address. Free the 2383 * physical pages underlying the relocated virtual pages. A virtual page 2384 * is relocatable if and only if it could be laundered or reclaimed by 2385 * the page daemon. Whenever possible, a virtual page is relocated to a 2386 * physical address above "high". 2387 * 2388 * Returns 0 if every physical page within the run was already free or 2389 * just freed by a successful relocation. Otherwise, returns a non-zero 2390 * value indicating why the last attempt to relocate a virtual page was 2391 * unsuccessful. 2392 * 2393 * "req_class" must be an allocation class. 2394 */ 2395 static int 2396 vm_page_reclaim_run(int req_class, u_long npages, vm_page_t m_run, 2397 vm_paddr_t high) 2398 { 2399 struct mtx *m_mtx, *new_mtx; 2400 struct spglist free; 2401 vm_object_t object; 2402 vm_paddr_t pa; 2403 vm_page_t m, m_end, m_new; 2404 int error, order, req; 2405 2406 KASSERT((req_class & VM_ALLOC_CLASS_MASK) == req_class, 2407 ("req_class is not an allocation class")); 2408 SLIST_INIT(&free); 2409 error = 0; 2410 m = m_run; 2411 m_end = m_run + npages; 2412 m_mtx = NULL; 2413 for (; error == 0 && m < m_end; m++) { 2414 KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0, 2415 ("page %p is PG_FICTITIOUS or PG_MARKER", m)); 2416 2417 /* 2418 * Avoid releasing and reacquiring the same page lock. 2419 */ 2420 new_mtx = vm_page_lockptr(m); 2421 if (m_mtx != new_mtx) { 2422 if (m_mtx != NULL) 2423 mtx_unlock(m_mtx); 2424 m_mtx = new_mtx; 2425 mtx_lock(m_mtx); 2426 } 2427 retry: 2428 if (m->wire_count != 0 || m->hold_count != 0) 2429 error = EBUSY; 2430 else if ((object = m->object) != NULL) { 2431 /* 2432 * The page is relocated if and only if it could be 2433 * laundered or reclaimed by the page daemon. 2434 */ 2435 if (!VM_OBJECT_TRYWLOCK(object)) { 2436 mtx_unlock(m_mtx); 2437 VM_OBJECT_WLOCK(object); 2438 mtx_lock(m_mtx); 2439 if (m->object != object) { 2440 /* 2441 * The page may have been freed. 2442 */ 2443 VM_OBJECT_WUNLOCK(object); 2444 goto retry; 2445 } else if (m->wire_count != 0 || 2446 m->hold_count != 0) { 2447 error = EBUSY; 2448 goto unlock; 2449 } 2450 } 2451 KASSERT((m->flags & PG_UNHOLDFREE) == 0, 2452 ("page %p is PG_UNHOLDFREE", m)); 2453 /* Don't care: PG_NODUMP, PG_WINATCFLS, PG_ZERO. */ 2454 if (object->type != OBJT_DEFAULT && 2455 object->type != OBJT_SWAP && 2456 object->type != OBJT_VNODE) 2457 error = EINVAL; 2458 else if ((m->flags & PG_CACHED) != 0 || 2459 m != vm_page_lookup(object, m->pindex)) { 2460 /* 2461 * The page is cached or recently converted 2462 * from cached to free. 2463 */ 2464 VM_OBJECT_WUNLOCK(object); 2465 goto cached; 2466 } else if (object->memattr != VM_MEMATTR_DEFAULT) 2467 error = EINVAL; 2468 else if (m->queue != PQ_NONE && !vm_page_busied(m)) { 2469 KASSERT(pmap_page_get_memattr(m) == 2470 VM_MEMATTR_DEFAULT, 2471 ("page %p has an unexpected memattr", m)); 2472 KASSERT((m->oflags & (VPO_SWAPINPROG | 2473 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, 2474 ("page %p has unexpected oflags", m)); 2475 /* Don't care: VPO_NOSYNC. */ 2476 if (m->valid != 0) { 2477 /* 2478 * First, try to allocate a new page 2479 * that is above "high". Failing 2480 * that, try to allocate a new page 2481 * that is below "m_run". Allocate 2482 * the new page between the end of 2483 * "m_run" and "high" only as a last 2484 * resort. 2485 */ 2486 req = req_class | VM_ALLOC_NOOBJ; 2487 if ((m->flags & PG_NODUMP) != 0) 2488 req |= VM_ALLOC_NODUMP; 2489 if (trunc_page(high) != 2490 ~(vm_paddr_t)PAGE_MASK) { 2491 m_new = vm_page_alloc_contig( 2492 NULL, 0, req, 1, 2493 round_page(high), 2494 ~(vm_paddr_t)0, 2495 PAGE_SIZE, 0, 2496 VM_MEMATTR_DEFAULT); 2497 } else 2498 m_new = NULL; 2499 if (m_new == NULL) { 2500 pa = VM_PAGE_TO_PHYS(m_run); 2501 m_new = vm_page_alloc_contig( 2502 NULL, 0, req, 1, 2503 0, pa - 1, PAGE_SIZE, 0, 2504 VM_MEMATTR_DEFAULT); 2505 } 2506 if (m_new == NULL) { 2507 pa += ptoa(npages); 2508 m_new = vm_page_alloc_contig( 2509 NULL, 0, req, 1, 2510 pa, high, PAGE_SIZE, 0, 2511 VM_MEMATTR_DEFAULT); 2512 } 2513 if (m_new == NULL) { 2514 error = ENOMEM; 2515 goto unlock; 2516 } 2517 KASSERT(m_new->wire_count == 0, 2518 ("page %p is wired", m)); 2519 2520 /* 2521 * Replace "m" with the new page. For 2522 * vm_page_replace(), "m" must be busy 2523 * and dequeued. Finally, change "m" 2524 * as if vm_page_free() was called. 2525 */ 2526 if (object->ref_count != 0) 2527 pmap_remove_all(m); 2528 m_new->aflags = m->aflags; 2529 KASSERT(m_new->oflags == VPO_UNMANAGED, 2530 ("page %p is managed", m)); 2531 m_new->oflags = m->oflags & VPO_NOSYNC; 2532 pmap_copy_page(m, m_new); 2533 m_new->valid = m->valid; 2534 m_new->dirty = m->dirty; 2535 m->flags &= ~PG_ZERO; 2536 vm_page_xbusy(m); 2537 vm_page_remque(m); 2538 vm_page_replace_checked(m_new, object, 2539 m->pindex, m); 2540 m->valid = 0; 2541 vm_page_undirty(m); 2542 2543 /* 2544 * The new page must be deactivated 2545 * before the object is unlocked. 2546 */ 2547 new_mtx = vm_page_lockptr(m_new); 2548 if (m_mtx != new_mtx) { 2549 mtx_unlock(m_mtx); 2550 m_mtx = new_mtx; 2551 mtx_lock(m_mtx); 2552 } 2553 vm_page_deactivate(m_new); 2554 } else { 2555 m->flags &= ~PG_ZERO; 2556 vm_page_remque(m); 2557 vm_page_remove(m); 2558 KASSERT(m->dirty == 0, 2559 ("page %p is dirty", m)); 2560 } 2561 SLIST_INSERT_HEAD(&free, m, plinks.s.ss); 2562 } else 2563 error = EBUSY; 2564 unlock: 2565 VM_OBJECT_WUNLOCK(object); 2566 } else { 2567 cached: 2568 mtx_lock(&vm_page_queue_free_mtx); 2569 order = m->order; 2570 if (order < VM_NFREEORDER) { 2571 /* 2572 * The page is enqueued in the physical memory 2573 * allocator's cache/free page queues. 2574 * Moreover, it is the first page in a power- 2575 * of-two-sized run of contiguous cache/free 2576 * pages. Jump ahead to the last page within 2577 * that run, and continue from there. 2578 */ 2579 m += (1 << order) - 1; 2580 } 2581 #if VM_NRESERVLEVEL > 0 2582 else if (vm_reserv_is_page_free(m)) 2583 order = 0; 2584 #endif 2585 mtx_unlock(&vm_page_queue_free_mtx); 2586 if (order == VM_NFREEORDER) 2587 error = EINVAL; 2588 } 2589 } 2590 if (m_mtx != NULL) 2591 mtx_unlock(m_mtx); 2592 if ((m = SLIST_FIRST(&free)) != NULL) { 2593 mtx_lock(&vm_page_queue_free_mtx); 2594 do { 2595 SLIST_REMOVE_HEAD(&free, plinks.s.ss); 2596 vm_phys_freecnt_adj(m, 1); 2597 #if VM_NRESERVLEVEL > 0 2598 if (!vm_reserv_free_page(m)) 2599 #else 2600 if (true) 2601 #endif 2602 vm_phys_free_pages(m, 0); 2603 } while ((m = SLIST_FIRST(&free)) != NULL); 2604 vm_page_free_wakeup(); 2605 mtx_unlock(&vm_page_queue_free_mtx); 2606 } 2607 return (error); 2608 } 2609 2610 #define NRUNS 16 2611 2612 CTASSERT(powerof2(NRUNS)); 2613 2614 #define RUN_INDEX(count) ((count) & (NRUNS - 1)) 2615 2616 #define MIN_RECLAIM 8 2617 2618 /* 2619 * vm_page_reclaim_contig: 2620 * 2621 * Reclaim allocated, contiguous physical memory satisfying the specified 2622 * conditions by relocating the virtual pages using that physical memory. 2623 * Returns true if reclamation is successful and false otherwise. Since 2624 * relocation requires the allocation of physical pages, reclamation may 2625 * fail due to a shortage of cache/free pages. When reclamation fails, 2626 * callers are expected to perform VM_WAIT before retrying a failed 2627 * allocation operation, e.g., vm_page_alloc_contig(). 2628 * 2629 * The caller must always specify an allocation class through "req". 2630 * 2631 * allocation classes: 2632 * VM_ALLOC_NORMAL normal process request 2633 * VM_ALLOC_SYSTEM system *really* needs a page 2634 * VM_ALLOC_INTERRUPT interrupt time request 2635 * 2636 * The optional allocation flags are ignored. 2637 * 2638 * "npages" must be greater than zero. Both "alignment" and "boundary" 2639 * must be a power of two. 2640 */ 2641 bool 2642 vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low, vm_paddr_t high, 2643 u_long alignment, vm_paddr_t boundary) 2644 { 2645 vm_paddr_t curr_low; 2646 vm_page_t m_run, m_runs[NRUNS]; 2647 u_long count, reclaimed; 2648 int error, i, options, req_class; 2649 2650 KASSERT(npages > 0, ("npages is 0")); 2651 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 2652 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 2653 req_class = req & VM_ALLOC_CLASS_MASK; 2654 2655 /* 2656 * The page daemon is allowed to dig deeper into the free page list. 2657 */ 2658 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 2659 req_class = VM_ALLOC_SYSTEM; 2660 2661 /* 2662 * Return if the number of cached and free pages cannot satisfy the 2663 * requested allocation. 2664 */ 2665 count = vm_cnt.v_free_count + vm_cnt.v_cache_count; 2666 if (count < npages + vm_cnt.v_free_reserved || (count < npages + 2667 vm_cnt.v_interrupt_free_min && req_class == VM_ALLOC_SYSTEM) || 2668 (count < npages && req_class == VM_ALLOC_INTERRUPT)) 2669 return (false); 2670 2671 /* 2672 * Scan up to three times, relaxing the restrictions ("options") on 2673 * the reclamation of reservations and superpages each time. 2674 */ 2675 for (options = VPSC_NORESERV;;) { 2676 /* 2677 * Find the highest runs that satisfy the given constraints 2678 * and restrictions, and record them in "m_runs". 2679 */ 2680 curr_low = low; 2681 count = 0; 2682 for (;;) { 2683 m_run = vm_phys_scan_contig(npages, curr_low, high, 2684 alignment, boundary, options); 2685 if (m_run == NULL) 2686 break; 2687 curr_low = VM_PAGE_TO_PHYS(m_run) + ptoa(npages); 2688 m_runs[RUN_INDEX(count)] = m_run; 2689 count++; 2690 } 2691 2692 /* 2693 * Reclaim the highest runs in LIFO (descending) order until 2694 * the number of reclaimed pages, "reclaimed", is at least 2695 * MIN_RECLAIM. Reset "reclaimed" each time because each 2696 * reclamation is idempotent, and runs will (likely) recur 2697 * from one scan to the next as restrictions are relaxed. 2698 */ 2699 reclaimed = 0; 2700 for (i = 0; count > 0 && i < NRUNS; i++) { 2701 count--; 2702 m_run = m_runs[RUN_INDEX(count)]; 2703 error = vm_page_reclaim_run(req_class, npages, m_run, 2704 high); 2705 if (error == 0) { 2706 reclaimed += npages; 2707 if (reclaimed >= MIN_RECLAIM) 2708 return (true); 2709 } 2710 } 2711 2712 /* 2713 * Either relax the restrictions on the next scan or return if 2714 * the last scan had no restrictions. 2715 */ 2716 if (options == VPSC_NORESERV) 2717 options = VPSC_NOSUPER; 2718 else if (options == VPSC_NOSUPER) 2719 options = VPSC_ANY; 2720 else if (options == VPSC_ANY) 2721 return (reclaimed != 0); 2722 } 2723 } 2724 2725 /* 2726 * vm_wait: (also see VM_WAIT macro) 2727 * 2728 * Sleep until free pages are available for allocation. 2729 * - Called in various places before memory allocations. 2730 */ 2731 void 2732 vm_wait(void) 2733 { 2734 2735 mtx_lock(&vm_page_queue_free_mtx); 2736 if (curproc == pageproc) { 2737 vm_pageout_pages_needed = 1; 2738 msleep(&vm_pageout_pages_needed, &vm_page_queue_free_mtx, 2739 PDROP | PSWP, "VMWait", 0); 2740 } else { 2741 if (!vm_pageout_wanted) { 2742 vm_pageout_wanted = true; 2743 wakeup(&vm_pageout_wanted); 2744 } 2745 vm_pages_needed = true; 2746 msleep(&vm_cnt.v_free_count, &vm_page_queue_free_mtx, PDROP | PVM, 2747 "vmwait", 0); 2748 } 2749 } 2750 2751 /* 2752 * vm_waitpfault: (also see VM_WAITPFAULT macro) 2753 * 2754 * Sleep until free pages are available for allocation. 2755 * - Called only in vm_fault so that processes page faulting 2756 * can be easily tracked. 2757 * - Sleeps at a lower priority than vm_wait() so that vm_wait()ing 2758 * processes will be able to grab memory first. Do not change 2759 * this balance without careful testing first. 2760 */ 2761 void 2762 vm_waitpfault(void) 2763 { 2764 2765 mtx_lock(&vm_page_queue_free_mtx); 2766 if (!vm_pageout_wanted) { 2767 vm_pageout_wanted = true; 2768 wakeup(&vm_pageout_wanted); 2769 } 2770 vm_pages_needed = true; 2771 msleep(&vm_cnt.v_free_count, &vm_page_queue_free_mtx, PDROP | PUSER, 2772 "pfault", 0); 2773 } 2774 2775 struct vm_pagequeue * 2776 vm_page_pagequeue(vm_page_t m) 2777 { 2778 2779 return (&vm_phys_domain(m)->vmd_pagequeues[m->queue]); 2780 } 2781 2782 /* 2783 * vm_page_dequeue: 2784 * 2785 * Remove the given page from its current page queue. 2786 * 2787 * The page must be locked. 2788 */ 2789 void 2790 vm_page_dequeue(vm_page_t m) 2791 { 2792 struct vm_pagequeue *pq; 2793 2794 vm_page_assert_locked(m); 2795 KASSERT(m->queue < PQ_COUNT, ("vm_page_dequeue: page %p is not queued", 2796 m)); 2797 pq = vm_page_pagequeue(m); 2798 vm_pagequeue_lock(pq); 2799 m->queue = PQ_NONE; 2800 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2801 vm_pagequeue_cnt_dec(pq); 2802 vm_pagequeue_unlock(pq); 2803 } 2804 2805 /* 2806 * vm_page_dequeue_locked: 2807 * 2808 * Remove the given page from its current page queue. 2809 * 2810 * The page and page queue must be locked. 2811 */ 2812 void 2813 vm_page_dequeue_locked(vm_page_t m) 2814 { 2815 struct vm_pagequeue *pq; 2816 2817 vm_page_lock_assert(m, MA_OWNED); 2818 pq = vm_page_pagequeue(m); 2819 vm_pagequeue_assert_locked(pq); 2820 m->queue = PQ_NONE; 2821 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2822 vm_pagequeue_cnt_dec(pq); 2823 } 2824 2825 /* 2826 * vm_page_enqueue: 2827 * 2828 * Add the given page to the specified page queue. 2829 * 2830 * The page must be locked. 2831 */ 2832 static void 2833 vm_page_enqueue(uint8_t queue, vm_page_t m) 2834 { 2835 struct vm_pagequeue *pq; 2836 2837 vm_page_lock_assert(m, MA_OWNED); 2838 KASSERT(queue < PQ_COUNT, 2839 ("vm_page_enqueue: invalid queue %u request for page %p", 2840 queue, m)); 2841 pq = &vm_phys_domain(m)->vmd_pagequeues[queue]; 2842 vm_pagequeue_lock(pq); 2843 m->queue = queue; 2844 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 2845 vm_pagequeue_cnt_inc(pq); 2846 vm_pagequeue_unlock(pq); 2847 } 2848 2849 /* 2850 * vm_page_requeue: 2851 * 2852 * Move the given page to the tail of its current page queue. 2853 * 2854 * The page must be locked. 2855 */ 2856 void 2857 vm_page_requeue(vm_page_t m) 2858 { 2859 struct vm_pagequeue *pq; 2860 2861 vm_page_lock_assert(m, MA_OWNED); 2862 KASSERT(m->queue != PQ_NONE, 2863 ("vm_page_requeue: page %p is not queued", m)); 2864 pq = vm_page_pagequeue(m); 2865 vm_pagequeue_lock(pq); 2866 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2867 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 2868 vm_pagequeue_unlock(pq); 2869 } 2870 2871 /* 2872 * vm_page_requeue_locked: 2873 * 2874 * Move the given page to the tail of its current page queue. 2875 * 2876 * The page queue must be locked. 2877 */ 2878 void 2879 vm_page_requeue_locked(vm_page_t m) 2880 { 2881 struct vm_pagequeue *pq; 2882 2883 KASSERT(m->queue != PQ_NONE, 2884 ("vm_page_requeue_locked: page %p is not queued", m)); 2885 pq = vm_page_pagequeue(m); 2886 vm_pagequeue_assert_locked(pq); 2887 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2888 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 2889 } 2890 2891 /* 2892 * vm_page_activate: 2893 * 2894 * Put the specified page on the active list (if appropriate). 2895 * Ensure that act_count is at least ACT_INIT but do not otherwise 2896 * mess with it. 2897 * 2898 * The page must be locked. 2899 */ 2900 void 2901 vm_page_activate(vm_page_t m) 2902 { 2903 int queue; 2904 2905 vm_page_lock_assert(m, MA_OWNED); 2906 if ((queue = m->queue) != PQ_ACTIVE) { 2907 if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) { 2908 if (m->act_count < ACT_INIT) 2909 m->act_count = ACT_INIT; 2910 if (queue != PQ_NONE) 2911 vm_page_dequeue(m); 2912 vm_page_enqueue(PQ_ACTIVE, m); 2913 } else 2914 KASSERT(queue == PQ_NONE, 2915 ("vm_page_activate: wired page %p is queued", m)); 2916 } else { 2917 if (m->act_count < ACT_INIT) 2918 m->act_count = ACT_INIT; 2919 } 2920 } 2921 2922 /* 2923 * vm_page_free_wakeup: 2924 * 2925 * Helper routine for vm_page_free_toq() and vm_page_cache(). This 2926 * routine is called when a page has been added to the cache or free 2927 * queues. 2928 * 2929 * The page queues must be locked. 2930 */ 2931 static inline void 2932 vm_page_free_wakeup(void) 2933 { 2934 2935 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 2936 /* 2937 * if pageout daemon needs pages, then tell it that there are 2938 * some free. 2939 */ 2940 if (vm_pageout_pages_needed && 2941 vm_cnt.v_cache_count + vm_cnt.v_free_count >= vm_cnt.v_pageout_free_min) { 2942 wakeup(&vm_pageout_pages_needed); 2943 vm_pageout_pages_needed = 0; 2944 } 2945 /* 2946 * wakeup processes that are waiting on memory if we hit a 2947 * high water mark. And wakeup scheduler process if we have 2948 * lots of memory. this process will swapin processes. 2949 */ 2950 if (vm_pages_needed && !vm_page_count_min()) { 2951 vm_pages_needed = false; 2952 wakeup(&vm_cnt.v_free_count); 2953 } 2954 } 2955 2956 /* 2957 * Turn a cached page into a free page, by changing its attributes. 2958 * Keep the statistics up-to-date. 2959 * 2960 * The free page queue must be locked. 2961 */ 2962 static void 2963 vm_page_cache_turn_free(vm_page_t m) 2964 { 2965 2966 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 2967 2968 m->object = NULL; 2969 m->valid = 0; 2970 KASSERT((m->flags & PG_CACHED) != 0, 2971 ("vm_page_cache_turn_free: page %p is not cached", m)); 2972 m->flags &= ~PG_CACHED; 2973 vm_cnt.v_cache_count--; 2974 vm_phys_freecnt_adj(m, 1); 2975 } 2976 2977 /* 2978 * vm_page_free_toq: 2979 * 2980 * Returns the given page to the free list, 2981 * disassociating it with any VM object. 2982 * 2983 * The object must be locked. The page must be locked if it is managed. 2984 */ 2985 void 2986 vm_page_free_toq(vm_page_t m) 2987 { 2988 2989 if ((m->oflags & VPO_UNMANAGED) == 0) { 2990 vm_page_lock_assert(m, MA_OWNED); 2991 KASSERT(!pmap_page_is_mapped(m), 2992 ("vm_page_free_toq: freeing mapped page %p", m)); 2993 } else 2994 KASSERT(m->queue == PQ_NONE, 2995 ("vm_page_free_toq: unmanaged page %p is queued", m)); 2996 PCPU_INC(cnt.v_tfree); 2997 2998 if (vm_page_sbusied(m)) 2999 panic("vm_page_free: freeing busy page %p", m); 3000 3001 /* 3002 * Unqueue, then remove page. Note that we cannot destroy 3003 * the page here because we do not want to call the pager's 3004 * callback routine until after we've put the page on the 3005 * appropriate free queue. 3006 */ 3007 vm_page_remque(m); 3008 vm_page_remove(m); 3009 3010 /* 3011 * If fictitious remove object association and 3012 * return, otherwise delay object association removal. 3013 */ 3014 if ((m->flags & PG_FICTITIOUS) != 0) { 3015 return; 3016 } 3017 3018 m->valid = 0; 3019 vm_page_undirty(m); 3020 3021 if (m->wire_count != 0) 3022 panic("vm_page_free: freeing wired page %p", m); 3023 if (m->hold_count != 0) { 3024 m->flags &= ~PG_ZERO; 3025 KASSERT((m->flags & PG_UNHOLDFREE) == 0, 3026 ("vm_page_free: freeing PG_UNHOLDFREE page %p", m)); 3027 m->flags |= PG_UNHOLDFREE; 3028 } else { 3029 /* 3030 * Restore the default memory attribute to the page. 3031 */ 3032 if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT) 3033 pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT); 3034 3035 /* 3036 * Insert the page into the physical memory allocator's 3037 * cache/free page queues. 3038 */ 3039 mtx_lock(&vm_page_queue_free_mtx); 3040 vm_phys_freecnt_adj(m, 1); 3041 #if VM_NRESERVLEVEL > 0 3042 if (!vm_reserv_free_page(m)) 3043 #else 3044 if (TRUE) 3045 #endif 3046 vm_phys_free_pages(m, 0); 3047 vm_page_free_wakeup(); 3048 mtx_unlock(&vm_page_queue_free_mtx); 3049 } 3050 } 3051 3052 /* 3053 * vm_page_wire: 3054 * 3055 * Mark this page as wired down by yet 3056 * another map, removing it from paging queues 3057 * as necessary. 3058 * 3059 * If the page is fictitious, then its wire count must remain one. 3060 * 3061 * The page must be locked. 3062 */ 3063 void 3064 vm_page_wire(vm_page_t m) 3065 { 3066 3067 /* 3068 * Only bump the wire statistics if the page is not already wired, 3069 * and only unqueue the page if it is on some queue (if it is unmanaged 3070 * it is already off the queues). 3071 */ 3072 vm_page_lock_assert(m, MA_OWNED); 3073 if ((m->flags & PG_FICTITIOUS) != 0) { 3074 KASSERT(m->wire_count == 1, 3075 ("vm_page_wire: fictitious page %p's wire count isn't one", 3076 m)); 3077 return; 3078 } 3079 if (m->wire_count == 0) { 3080 KASSERT((m->oflags & VPO_UNMANAGED) == 0 || 3081 m->queue == PQ_NONE, 3082 ("vm_page_wire: unmanaged page %p is queued", m)); 3083 vm_page_remque(m); 3084 atomic_add_int(&vm_cnt.v_wire_count, 1); 3085 } 3086 m->wire_count++; 3087 KASSERT(m->wire_count != 0, ("vm_page_wire: wire_count overflow m=%p", m)); 3088 } 3089 3090 /* 3091 * vm_page_unwire: 3092 * 3093 * Release one wiring of the specified page, potentially allowing it to be 3094 * paged out. Returns TRUE if the number of wirings transitions to zero and 3095 * FALSE otherwise. 3096 * 3097 * Only managed pages belonging to an object can be paged out. If the number 3098 * of wirings transitions to zero and the page is eligible for page out, then 3099 * the page is added to the specified paging queue (unless PQ_NONE is 3100 * specified). 3101 * 3102 * If a page is fictitious, then its wire count must always be one. 3103 * 3104 * A managed page must be locked. 3105 */ 3106 boolean_t 3107 vm_page_unwire(vm_page_t m, uint8_t queue) 3108 { 3109 3110 KASSERT(queue < PQ_COUNT || queue == PQ_NONE, 3111 ("vm_page_unwire: invalid queue %u request for page %p", 3112 queue, m)); 3113 if ((m->oflags & VPO_UNMANAGED) == 0) 3114 vm_page_assert_locked(m); 3115 if ((m->flags & PG_FICTITIOUS) != 0) { 3116 KASSERT(m->wire_count == 1, 3117 ("vm_page_unwire: fictitious page %p's wire count isn't one", m)); 3118 return (FALSE); 3119 } 3120 if (m->wire_count > 0) { 3121 m->wire_count--; 3122 if (m->wire_count == 0) { 3123 atomic_subtract_int(&vm_cnt.v_wire_count, 1); 3124 if ((m->oflags & VPO_UNMANAGED) == 0 && 3125 m->object != NULL && queue != PQ_NONE) { 3126 if (queue == PQ_INACTIVE) 3127 m->flags &= ~PG_WINATCFLS; 3128 vm_page_enqueue(queue, m); 3129 } 3130 return (TRUE); 3131 } else 3132 return (FALSE); 3133 } else 3134 panic("vm_page_unwire: page %p's wire count is zero", m); 3135 } 3136 3137 /* 3138 * Move the specified page to the inactive queue. 3139 * 3140 * Many pages placed on the inactive queue should actually go 3141 * into the cache, but it is difficult to figure out which. What 3142 * we do instead, if the inactive target is well met, is to put 3143 * clean pages at the head of the inactive queue instead of the tail. 3144 * This will cause them to be moved to the cache more quickly and 3145 * if not actively re-referenced, reclaimed more quickly. If we just 3146 * stick these pages at the end of the inactive queue, heavy filesystem 3147 * meta-data accesses can cause an unnecessary paging load on memory bound 3148 * processes. This optimization causes one-time-use metadata to be 3149 * reused more quickly. 3150 * 3151 * Normally noreuse is FALSE, resulting in LRU operation. noreuse is set 3152 * to TRUE if we want this page to be 'as if it were placed in the cache', 3153 * except without unmapping it from the process address space. In 3154 * practice this is implemented by inserting the page at the head of the 3155 * queue, using a marker page to guide FIFO insertion ordering. 3156 * 3157 * The page must be locked. 3158 */ 3159 static inline void 3160 _vm_page_deactivate(vm_page_t m, boolean_t noreuse) 3161 { 3162 struct vm_pagequeue *pq; 3163 int queue; 3164 3165 vm_page_assert_locked(m); 3166 3167 /* 3168 * Ignore if the page is already inactive, unless it is unlikely to be 3169 * reactivated. 3170 */ 3171 if ((queue = m->queue) == PQ_INACTIVE && !noreuse) 3172 return; 3173 if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) { 3174 pq = &vm_phys_domain(m)->vmd_pagequeues[PQ_INACTIVE]; 3175 /* Avoid multiple acquisitions of the inactive queue lock. */ 3176 if (queue == PQ_INACTIVE) { 3177 vm_pagequeue_lock(pq); 3178 vm_page_dequeue_locked(m); 3179 } else { 3180 if (queue != PQ_NONE) 3181 vm_page_dequeue(m); 3182 m->flags &= ~PG_WINATCFLS; 3183 vm_pagequeue_lock(pq); 3184 } 3185 m->queue = PQ_INACTIVE; 3186 if (noreuse) 3187 TAILQ_INSERT_BEFORE(&vm_phys_domain(m)->vmd_inacthead, 3188 m, plinks.q); 3189 else 3190 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 3191 vm_pagequeue_cnt_inc(pq); 3192 vm_pagequeue_unlock(pq); 3193 } 3194 } 3195 3196 /* 3197 * Move the specified page to the inactive queue. 3198 * 3199 * The page must be locked. 3200 */ 3201 void 3202 vm_page_deactivate(vm_page_t m) 3203 { 3204 3205 _vm_page_deactivate(m, FALSE); 3206 } 3207 3208 /* 3209 * Move the specified page to the inactive queue with the expectation 3210 * that it is unlikely to be reused. 3211 * 3212 * The page must be locked. 3213 */ 3214 void 3215 vm_page_deactivate_noreuse(vm_page_t m) 3216 { 3217 3218 _vm_page_deactivate(m, TRUE); 3219 } 3220 3221 /* 3222 * vm_page_try_to_cache: 3223 * 3224 * Returns 0 on failure, 1 on success 3225 */ 3226 int 3227 vm_page_try_to_cache(vm_page_t m) 3228 { 3229 3230 vm_page_lock_assert(m, MA_OWNED); 3231 VM_OBJECT_ASSERT_WLOCKED(m->object); 3232 if (m->dirty || m->hold_count || m->wire_count || 3233 (m->oflags & VPO_UNMANAGED) != 0 || vm_page_busied(m)) 3234 return (0); 3235 pmap_remove_all(m); 3236 if (m->dirty) 3237 return (0); 3238 vm_page_cache(m); 3239 return (1); 3240 } 3241 3242 /* 3243 * vm_page_try_to_free() 3244 * 3245 * Attempt to free the page. If we cannot free it, we do nothing. 3246 * 1 is returned on success, 0 on failure. 3247 */ 3248 int 3249 vm_page_try_to_free(vm_page_t m) 3250 { 3251 3252 vm_page_lock_assert(m, MA_OWNED); 3253 if (m->object != NULL) 3254 VM_OBJECT_ASSERT_WLOCKED(m->object); 3255 if (m->dirty || m->hold_count || m->wire_count || 3256 (m->oflags & VPO_UNMANAGED) != 0 || vm_page_busied(m)) 3257 return (0); 3258 pmap_remove_all(m); 3259 if (m->dirty) 3260 return (0); 3261 vm_page_free(m); 3262 return (1); 3263 } 3264 3265 /* 3266 * vm_page_cache 3267 * 3268 * Put the specified page onto the page cache queue (if appropriate). 3269 * 3270 * The object and page must be locked. 3271 */ 3272 void 3273 vm_page_cache(vm_page_t m) 3274 { 3275 vm_object_t object; 3276 boolean_t cache_was_empty; 3277 3278 vm_page_lock_assert(m, MA_OWNED); 3279 object = m->object; 3280 VM_OBJECT_ASSERT_WLOCKED(object); 3281 if (vm_page_busied(m) || (m->oflags & VPO_UNMANAGED) || 3282 m->hold_count || m->wire_count) 3283 panic("vm_page_cache: attempting to cache busy page"); 3284 KASSERT(!pmap_page_is_mapped(m), 3285 ("vm_page_cache: page %p is mapped", m)); 3286 KASSERT(m->dirty == 0, ("vm_page_cache: page %p is dirty", m)); 3287 if (m->valid == 0 || object->type == OBJT_DEFAULT || 3288 (object->type == OBJT_SWAP && 3289 !vm_pager_has_page(object, m->pindex, NULL, NULL))) { 3290 /* 3291 * Hypothesis: A cache-eligible page belonging to a 3292 * default object or swap object but without a backing 3293 * store must be zero filled. 3294 */ 3295 vm_page_free(m); 3296 return; 3297 } 3298 KASSERT((m->flags & PG_CACHED) == 0, 3299 ("vm_page_cache: page %p is already cached", m)); 3300 3301 /* 3302 * Remove the page from the paging queues. 3303 */ 3304 vm_page_remque(m); 3305 3306 /* 3307 * Remove the page from the object's collection of resident 3308 * pages. 3309 */ 3310 vm_radix_remove(&object->rtree, m->pindex); 3311 TAILQ_REMOVE(&object->memq, m, listq); 3312 object->resident_page_count--; 3313 3314 /* 3315 * Restore the default memory attribute to the page. 3316 */ 3317 if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT) 3318 pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT); 3319 3320 /* 3321 * Insert the page into the object's collection of cached pages 3322 * and the physical memory allocator's cache/free page queues. 3323 */ 3324 m->flags &= ~PG_ZERO; 3325 mtx_lock(&vm_page_queue_free_mtx); 3326 cache_was_empty = vm_radix_is_empty(&object->cache); 3327 if (vm_radix_insert(&object->cache, m)) { 3328 mtx_unlock(&vm_page_queue_free_mtx); 3329 if (object->type == OBJT_VNODE && 3330 object->resident_page_count == 0) 3331 vdrop(object->handle); 3332 m->object = NULL; 3333 vm_page_free(m); 3334 return; 3335 } 3336 3337 /* 3338 * The above call to vm_radix_insert() could reclaim the one pre- 3339 * existing cached page from this object, resulting in a call to 3340 * vdrop(). 3341 */ 3342 if (!cache_was_empty) 3343 cache_was_empty = vm_radix_is_singleton(&object->cache); 3344 3345 m->flags |= PG_CACHED; 3346 vm_cnt.v_cache_count++; 3347 PCPU_INC(cnt.v_tcached); 3348 #if VM_NRESERVLEVEL > 0 3349 if (!vm_reserv_free_page(m)) { 3350 #else 3351 if (TRUE) { 3352 #endif 3353 vm_phys_free_pages(m, 0); 3354 } 3355 vm_page_free_wakeup(); 3356 mtx_unlock(&vm_page_queue_free_mtx); 3357 3358 /* 3359 * Increment the vnode's hold count if this is the object's only 3360 * cached page. Decrement the vnode's hold count if this was 3361 * the object's only resident page. 3362 */ 3363 if (object->type == OBJT_VNODE) { 3364 if (cache_was_empty && object->resident_page_count != 0) 3365 vhold(object->handle); 3366 else if (!cache_was_empty && object->resident_page_count == 0) 3367 vdrop(object->handle); 3368 } 3369 } 3370 3371 /* 3372 * vm_page_advise 3373 * 3374 * Deactivate or do nothing, as appropriate. 3375 * 3376 * The object and page must be locked. 3377 */ 3378 void 3379 vm_page_advise(vm_page_t m, int advice) 3380 { 3381 3382 vm_page_assert_locked(m); 3383 VM_OBJECT_ASSERT_WLOCKED(m->object); 3384 if (advice == MADV_FREE) 3385 /* 3386 * Mark the page clean. This will allow the page to be freed 3387 * up by the system. However, such pages are often reused 3388 * quickly by malloc() so we do not do anything that would 3389 * cause a page fault if we can help it. 3390 * 3391 * Specifically, we do not try to actually free the page now 3392 * nor do we try to put it in the cache (which would cause a 3393 * page fault on reuse). 3394 * 3395 * But we do make the page as freeable as we can without 3396 * actually taking the step of unmapping it. 3397 */ 3398 vm_page_undirty(m); 3399 else if (advice != MADV_DONTNEED) 3400 return; 3401 3402 /* 3403 * Clear any references to the page. Otherwise, the page daemon will 3404 * immediately reactivate the page. 3405 */ 3406 vm_page_aflag_clear(m, PGA_REFERENCED); 3407 3408 if (advice != MADV_FREE && m->dirty == 0 && pmap_is_modified(m)) 3409 vm_page_dirty(m); 3410 3411 /* 3412 * Place clean pages near the head of the inactive queue rather than 3413 * the tail, thus defeating the queue's LRU operation and ensuring that 3414 * the page will be reused quickly. Dirty pages are given a chance to 3415 * cycle once through the inactive queue before becoming eligible for 3416 * laundering. 3417 */ 3418 _vm_page_deactivate(m, m->dirty == 0); 3419 } 3420 3421 /* 3422 * Grab a page, waiting until we are waken up due to the page 3423 * changing state. We keep on waiting, if the page continues 3424 * to be in the object. If the page doesn't exist, first allocate it 3425 * and then conditionally zero it. 3426 * 3427 * This routine may sleep. 3428 * 3429 * The object must be locked on entry. The lock will, however, be released 3430 * and reacquired if the routine sleeps. 3431 */ 3432 vm_page_t 3433 vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags) 3434 { 3435 vm_page_t m; 3436 int sleep; 3437 3438 VM_OBJECT_ASSERT_WLOCKED(object); 3439 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || 3440 (allocflags & VM_ALLOC_IGN_SBUSY) != 0, 3441 ("vm_page_grab: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch")); 3442 retrylookup: 3443 if ((m = vm_page_lookup(object, pindex)) != NULL) { 3444 sleep = (allocflags & VM_ALLOC_IGN_SBUSY) != 0 ? 3445 vm_page_xbusied(m) : vm_page_busied(m); 3446 if (sleep) { 3447 if ((allocflags & VM_ALLOC_NOWAIT) != 0) 3448 return (NULL); 3449 /* 3450 * Reference the page before unlocking and 3451 * sleeping so that the page daemon is less 3452 * likely to reclaim it. 3453 */ 3454 vm_page_aflag_set(m, PGA_REFERENCED); 3455 vm_page_lock(m); 3456 VM_OBJECT_WUNLOCK(object); 3457 vm_page_busy_sleep(m, "pgrbwt", (allocflags & 3458 VM_ALLOC_IGN_SBUSY) != 0); 3459 VM_OBJECT_WLOCK(object); 3460 goto retrylookup; 3461 } else { 3462 if ((allocflags & VM_ALLOC_WIRED) != 0) { 3463 vm_page_lock(m); 3464 vm_page_wire(m); 3465 vm_page_unlock(m); 3466 } 3467 if ((allocflags & 3468 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0) 3469 vm_page_xbusy(m); 3470 if ((allocflags & VM_ALLOC_SBUSY) != 0) 3471 vm_page_sbusy(m); 3472 return (m); 3473 } 3474 } 3475 m = vm_page_alloc(object, pindex, allocflags); 3476 if (m == NULL) { 3477 if ((allocflags & VM_ALLOC_NOWAIT) != 0) 3478 return (NULL); 3479 VM_OBJECT_WUNLOCK(object); 3480 VM_WAIT; 3481 VM_OBJECT_WLOCK(object); 3482 goto retrylookup; 3483 } else if (m->valid != 0) 3484 return (m); 3485 if (allocflags & VM_ALLOC_ZERO && (m->flags & PG_ZERO) == 0) 3486 pmap_zero_page(m); 3487 return (m); 3488 } 3489 3490 /* 3491 * Mapping function for valid or dirty bits in a page. 3492 * 3493 * Inputs are required to range within a page. 3494 */ 3495 vm_page_bits_t 3496 vm_page_bits(int base, int size) 3497 { 3498 int first_bit; 3499 int last_bit; 3500 3501 KASSERT( 3502 base + size <= PAGE_SIZE, 3503 ("vm_page_bits: illegal base/size %d/%d", base, size) 3504 ); 3505 3506 if (size == 0) /* handle degenerate case */ 3507 return (0); 3508 3509 first_bit = base >> DEV_BSHIFT; 3510 last_bit = (base + size - 1) >> DEV_BSHIFT; 3511 3512 return (((vm_page_bits_t)2 << last_bit) - 3513 ((vm_page_bits_t)1 << first_bit)); 3514 } 3515 3516 /* 3517 * vm_page_set_valid_range: 3518 * 3519 * Sets portions of a page valid. The arguments are expected 3520 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive 3521 * of any partial chunks touched by the range. The invalid portion of 3522 * such chunks will be zeroed. 3523 * 3524 * (base + size) must be less then or equal to PAGE_SIZE. 3525 */ 3526 void 3527 vm_page_set_valid_range(vm_page_t m, int base, int size) 3528 { 3529 int endoff, frag; 3530 3531 VM_OBJECT_ASSERT_WLOCKED(m->object); 3532 if (size == 0) /* handle degenerate case */ 3533 return; 3534 3535 /* 3536 * If the base is not DEV_BSIZE aligned and the valid 3537 * bit is clear, we have to zero out a portion of the 3538 * first block. 3539 */ 3540 if ((frag = rounddown2(base, DEV_BSIZE)) != base && 3541 (m->valid & (1 << (base >> DEV_BSHIFT))) == 0) 3542 pmap_zero_page_area(m, frag, base - frag); 3543 3544 /* 3545 * If the ending offset is not DEV_BSIZE aligned and the 3546 * valid bit is clear, we have to zero out a portion of 3547 * the last block. 3548 */ 3549 endoff = base + size; 3550 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && 3551 (m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0) 3552 pmap_zero_page_area(m, endoff, 3553 DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); 3554 3555 /* 3556 * Assert that no previously invalid block that is now being validated 3557 * is already dirty. 3558 */ 3559 KASSERT((~m->valid & vm_page_bits(base, size) & m->dirty) == 0, 3560 ("vm_page_set_valid_range: page %p is dirty", m)); 3561 3562 /* 3563 * Set valid bits inclusive of any overlap. 3564 */ 3565 m->valid |= vm_page_bits(base, size); 3566 } 3567 3568 /* 3569 * Clear the given bits from the specified page's dirty field. 3570 */ 3571 static __inline void 3572 vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits) 3573 { 3574 uintptr_t addr; 3575 #if PAGE_SIZE < 16384 3576 int shift; 3577 #endif 3578 3579 /* 3580 * If the object is locked and the page is neither exclusive busy nor 3581 * write mapped, then the page's dirty field cannot possibly be 3582 * set by a concurrent pmap operation. 3583 */ 3584 VM_OBJECT_ASSERT_WLOCKED(m->object); 3585 if (!vm_page_xbusied(m) && !pmap_page_is_write_mapped(m)) 3586 m->dirty &= ~pagebits; 3587 else { 3588 /* 3589 * The pmap layer can call vm_page_dirty() without 3590 * holding a distinguished lock. The combination of 3591 * the object's lock and an atomic operation suffice 3592 * to guarantee consistency of the page dirty field. 3593 * 3594 * For PAGE_SIZE == 32768 case, compiler already 3595 * properly aligns the dirty field, so no forcible 3596 * alignment is needed. Only require existence of 3597 * atomic_clear_64 when page size is 32768. 3598 */ 3599 addr = (uintptr_t)&m->dirty; 3600 #if PAGE_SIZE == 32768 3601 atomic_clear_64((uint64_t *)addr, pagebits); 3602 #elif PAGE_SIZE == 16384 3603 atomic_clear_32((uint32_t *)addr, pagebits); 3604 #else /* PAGE_SIZE <= 8192 */ 3605 /* 3606 * Use a trick to perform a 32-bit atomic on the 3607 * containing aligned word, to not depend on the existence 3608 * of atomic_clear_{8, 16}. 3609 */ 3610 shift = addr & (sizeof(uint32_t) - 1); 3611 #if BYTE_ORDER == BIG_ENDIAN 3612 shift = (sizeof(uint32_t) - sizeof(m->dirty) - shift) * NBBY; 3613 #else 3614 shift *= NBBY; 3615 #endif 3616 addr &= ~(sizeof(uint32_t) - 1); 3617 atomic_clear_32((uint32_t *)addr, pagebits << shift); 3618 #endif /* PAGE_SIZE */ 3619 } 3620 } 3621 3622 /* 3623 * vm_page_set_validclean: 3624 * 3625 * Sets portions of a page valid and clean. The arguments are expected 3626 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive 3627 * of any partial chunks touched by the range. The invalid portion of 3628 * such chunks will be zero'd. 3629 * 3630 * (base + size) must be less then or equal to PAGE_SIZE. 3631 */ 3632 void 3633 vm_page_set_validclean(vm_page_t m, int base, int size) 3634 { 3635 vm_page_bits_t oldvalid, pagebits; 3636 int endoff, frag; 3637 3638 VM_OBJECT_ASSERT_WLOCKED(m->object); 3639 if (size == 0) /* handle degenerate case */ 3640 return; 3641 3642 /* 3643 * If the base is not DEV_BSIZE aligned and the valid 3644 * bit is clear, we have to zero out a portion of the 3645 * first block. 3646 */ 3647 if ((frag = rounddown2(base, DEV_BSIZE)) != base && 3648 (m->valid & ((vm_page_bits_t)1 << (base >> DEV_BSHIFT))) == 0) 3649 pmap_zero_page_area(m, frag, base - frag); 3650 3651 /* 3652 * If the ending offset is not DEV_BSIZE aligned and the 3653 * valid bit is clear, we have to zero out a portion of 3654 * the last block. 3655 */ 3656 endoff = base + size; 3657 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && 3658 (m->valid & ((vm_page_bits_t)1 << (endoff >> DEV_BSHIFT))) == 0) 3659 pmap_zero_page_area(m, endoff, 3660 DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); 3661 3662 /* 3663 * Set valid, clear dirty bits. If validating the entire 3664 * page we can safely clear the pmap modify bit. We also 3665 * use this opportunity to clear the VPO_NOSYNC flag. If a process 3666 * takes a write fault on a MAP_NOSYNC memory area the flag will 3667 * be set again. 3668 * 3669 * We set valid bits inclusive of any overlap, but we can only 3670 * clear dirty bits for DEV_BSIZE chunks that are fully within 3671 * the range. 3672 */ 3673 oldvalid = m->valid; 3674 pagebits = vm_page_bits(base, size); 3675 m->valid |= pagebits; 3676 #if 0 /* NOT YET */ 3677 if ((frag = base & (DEV_BSIZE - 1)) != 0) { 3678 frag = DEV_BSIZE - frag; 3679 base += frag; 3680 size -= frag; 3681 if (size < 0) 3682 size = 0; 3683 } 3684 pagebits = vm_page_bits(base, size & (DEV_BSIZE - 1)); 3685 #endif 3686 if (base == 0 && size == PAGE_SIZE) { 3687 /* 3688 * The page can only be modified within the pmap if it is 3689 * mapped, and it can only be mapped if it was previously 3690 * fully valid. 3691 */ 3692 if (oldvalid == VM_PAGE_BITS_ALL) 3693 /* 3694 * Perform the pmap_clear_modify() first. Otherwise, 3695 * a concurrent pmap operation, such as 3696 * pmap_protect(), could clear a modification in the 3697 * pmap and set the dirty field on the page before 3698 * pmap_clear_modify() had begun and after the dirty 3699 * field was cleared here. 3700 */ 3701 pmap_clear_modify(m); 3702 m->dirty = 0; 3703 m->oflags &= ~VPO_NOSYNC; 3704 } else if (oldvalid != VM_PAGE_BITS_ALL) 3705 m->dirty &= ~pagebits; 3706 else 3707 vm_page_clear_dirty_mask(m, pagebits); 3708 } 3709 3710 void 3711 vm_page_clear_dirty(vm_page_t m, int base, int size) 3712 { 3713 3714 vm_page_clear_dirty_mask(m, vm_page_bits(base, size)); 3715 } 3716 3717 /* 3718 * vm_page_set_invalid: 3719 * 3720 * Invalidates DEV_BSIZE'd chunks within a page. Both the 3721 * valid and dirty bits for the effected areas are cleared. 3722 */ 3723 void 3724 vm_page_set_invalid(vm_page_t m, int base, int size) 3725 { 3726 vm_page_bits_t bits; 3727 vm_object_t object; 3728 3729 object = m->object; 3730 VM_OBJECT_ASSERT_WLOCKED(object); 3731 if (object->type == OBJT_VNODE && base == 0 && IDX_TO_OFF(m->pindex) + 3732 size >= object->un_pager.vnp.vnp_size) 3733 bits = VM_PAGE_BITS_ALL; 3734 else 3735 bits = vm_page_bits(base, size); 3736 if (object->ref_count != 0 && m->valid == VM_PAGE_BITS_ALL && 3737 bits != 0) 3738 pmap_remove_all(m); 3739 KASSERT((bits == 0 && m->valid == VM_PAGE_BITS_ALL) || 3740 !pmap_page_is_mapped(m), 3741 ("vm_page_set_invalid: page %p is mapped", m)); 3742 m->valid &= ~bits; 3743 m->dirty &= ~bits; 3744 } 3745 3746 /* 3747 * vm_page_zero_invalid() 3748 * 3749 * The kernel assumes that the invalid portions of a page contain 3750 * garbage, but such pages can be mapped into memory by user code. 3751 * When this occurs, we must zero out the non-valid portions of the 3752 * page so user code sees what it expects. 3753 * 3754 * Pages are most often semi-valid when the end of a file is mapped 3755 * into memory and the file's size is not page aligned. 3756 */ 3757 void 3758 vm_page_zero_invalid(vm_page_t m, boolean_t setvalid) 3759 { 3760 int b; 3761 int i; 3762 3763 VM_OBJECT_ASSERT_WLOCKED(m->object); 3764 /* 3765 * Scan the valid bits looking for invalid sections that 3766 * must be zeroed. Invalid sub-DEV_BSIZE'd areas ( where the 3767 * valid bit may be set ) have already been zeroed by 3768 * vm_page_set_validclean(). 3769 */ 3770 for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) { 3771 if (i == (PAGE_SIZE / DEV_BSIZE) || 3772 (m->valid & ((vm_page_bits_t)1 << i))) { 3773 if (i > b) { 3774 pmap_zero_page_area(m, 3775 b << DEV_BSHIFT, (i - b) << DEV_BSHIFT); 3776 } 3777 b = i + 1; 3778 } 3779 } 3780 3781 /* 3782 * setvalid is TRUE when we can safely set the zero'd areas 3783 * as being valid. We can do this if there are no cache consistancy 3784 * issues. e.g. it is ok to do with UFS, but not ok to do with NFS. 3785 */ 3786 if (setvalid) 3787 m->valid = VM_PAGE_BITS_ALL; 3788 } 3789 3790 /* 3791 * vm_page_is_valid: 3792 * 3793 * Is (partial) page valid? Note that the case where size == 0 3794 * will return FALSE in the degenerate case where the page is 3795 * entirely invalid, and TRUE otherwise. 3796 */ 3797 int 3798 vm_page_is_valid(vm_page_t m, int base, int size) 3799 { 3800 vm_page_bits_t bits; 3801 3802 VM_OBJECT_ASSERT_LOCKED(m->object); 3803 bits = vm_page_bits(base, size); 3804 return (m->valid != 0 && (m->valid & bits) == bits); 3805 } 3806 3807 /* 3808 * vm_page_ps_is_valid: 3809 * 3810 * Returns TRUE if the entire (super)page is valid and FALSE otherwise. 3811 */ 3812 boolean_t 3813 vm_page_ps_is_valid(vm_page_t m) 3814 { 3815 int i, npages; 3816 3817 VM_OBJECT_ASSERT_LOCKED(m->object); 3818 npages = atop(pagesizes[m->psind]); 3819 3820 /* 3821 * The physically contiguous pages that make up a superpage, i.e., a 3822 * page with a page size index ("psind") greater than zero, will 3823 * occupy adjacent entries in vm_page_array[]. 3824 */ 3825 for (i = 0; i < npages; i++) { 3826 if (m[i].valid != VM_PAGE_BITS_ALL) 3827 return (FALSE); 3828 } 3829 return (TRUE); 3830 } 3831 3832 /* 3833 * Set the page's dirty bits if the page is modified. 3834 */ 3835 void 3836 vm_page_test_dirty(vm_page_t m) 3837 { 3838 3839 VM_OBJECT_ASSERT_WLOCKED(m->object); 3840 if (m->dirty != VM_PAGE_BITS_ALL && pmap_is_modified(m)) 3841 vm_page_dirty(m); 3842 } 3843 3844 void 3845 vm_page_lock_KBI(vm_page_t m, const char *file, int line) 3846 { 3847 3848 mtx_lock_flags_(vm_page_lockptr(m), 0, file, line); 3849 } 3850 3851 void 3852 vm_page_unlock_KBI(vm_page_t m, const char *file, int line) 3853 { 3854 3855 mtx_unlock_flags_(vm_page_lockptr(m), 0, file, line); 3856 } 3857 3858 int 3859 vm_page_trylock_KBI(vm_page_t m, const char *file, int line) 3860 { 3861 3862 return (mtx_trylock_flags_(vm_page_lockptr(m), 0, file, line)); 3863 } 3864 3865 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT) 3866 void 3867 vm_page_assert_locked_KBI(vm_page_t m, const char *file, int line) 3868 { 3869 3870 vm_page_lock_assert_KBI(m, MA_OWNED, file, line); 3871 } 3872 3873 void 3874 vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line) 3875 { 3876 3877 mtx_assert_(vm_page_lockptr(m), a, file, line); 3878 } 3879 #endif 3880 3881 #ifdef INVARIANTS 3882 void 3883 vm_page_object_lock_assert(vm_page_t m) 3884 { 3885 3886 /* 3887 * Certain of the page's fields may only be modified by the 3888 * holder of the containing object's lock or the exclusive busy. 3889 * holder. Unfortunately, the holder of the write busy is 3890 * not recorded, and thus cannot be checked here. 3891 */ 3892 if (m->object != NULL && !vm_page_xbusied(m)) 3893 VM_OBJECT_ASSERT_WLOCKED(m->object); 3894 } 3895 3896 void 3897 vm_page_assert_pga_writeable(vm_page_t m, uint8_t bits) 3898 { 3899 3900 if ((bits & PGA_WRITEABLE) == 0) 3901 return; 3902 3903 /* 3904 * The PGA_WRITEABLE flag can only be set if the page is 3905 * managed, is exclusively busied or the object is locked. 3906 * Currently, this flag is only set by pmap_enter(). 3907 */ 3908 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 3909 ("PGA_WRITEABLE on unmanaged page")); 3910 if (!vm_page_xbusied(m)) 3911 VM_OBJECT_ASSERT_LOCKED(m->object); 3912 } 3913 #endif 3914 3915 #include "opt_ddb.h" 3916 #ifdef DDB 3917 #include <sys/kernel.h> 3918 3919 #include <ddb/ddb.h> 3920 3921 DB_SHOW_COMMAND(page, vm_page_print_page_info) 3922 { 3923 db_printf("vm_cnt.v_free_count: %d\n", vm_cnt.v_free_count); 3924 db_printf("vm_cnt.v_cache_count: %d\n", vm_cnt.v_cache_count); 3925 db_printf("vm_cnt.v_inactive_count: %d\n", vm_cnt.v_inactive_count); 3926 db_printf("vm_cnt.v_active_count: %d\n", vm_cnt.v_active_count); 3927 db_printf("vm_cnt.v_wire_count: %d\n", vm_cnt.v_wire_count); 3928 db_printf("vm_cnt.v_free_reserved: %d\n", vm_cnt.v_free_reserved); 3929 db_printf("vm_cnt.v_free_min: %d\n", vm_cnt.v_free_min); 3930 db_printf("vm_cnt.v_free_target: %d\n", vm_cnt.v_free_target); 3931 db_printf("vm_cnt.v_inactive_target: %d\n", vm_cnt.v_inactive_target); 3932 } 3933 3934 DB_SHOW_COMMAND(pageq, vm_page_print_pageq_info) 3935 { 3936 int dom; 3937 3938 db_printf("pq_free %d pq_cache %d\n", 3939 vm_cnt.v_free_count, vm_cnt.v_cache_count); 3940 for (dom = 0; dom < vm_ndomains; dom++) { 3941 db_printf("dom %d page_cnt %d free %d pq_act %d pq_inact %d\n", 3942 dom, 3943 vm_dom[dom].vmd_page_count, 3944 vm_dom[dom].vmd_free_count, 3945 vm_dom[dom].vmd_pagequeues[PQ_ACTIVE].pq_cnt, 3946 vm_dom[dom].vmd_pagequeues[PQ_INACTIVE].pq_cnt); 3947 } 3948 } 3949 3950 DB_SHOW_COMMAND(pginfo, vm_page_print_pginfo) 3951 { 3952 vm_page_t m; 3953 boolean_t phys; 3954 3955 if (!have_addr) { 3956 db_printf("show pginfo addr\n"); 3957 return; 3958 } 3959 3960 phys = strchr(modif, 'p') != NULL; 3961 if (phys) 3962 m = PHYS_TO_VM_PAGE(addr); 3963 else 3964 m = (vm_page_t)addr; 3965 db_printf( 3966 "page %p obj %p pidx 0x%jx phys 0x%jx q %d hold %d wire %d\n" 3967 " af 0x%x of 0x%x f 0x%x act %d busy %x valid 0x%x dirty 0x%x\n", 3968 m, m->object, (uintmax_t)m->pindex, (uintmax_t)m->phys_addr, 3969 m->queue, m->hold_count, m->wire_count, m->aflags, m->oflags, 3970 m->flags, m->act_count, m->busy_lock, m->valid, m->dirty); 3971 } 3972 #endif /* DDB */ 3973