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 void 746 vm_page_busy_sleep(vm_page_t m, const char *wmesg) 747 { 748 u_int x; 749 750 vm_page_lock_assert(m, MA_OWNED); 751 752 x = m->busy_lock; 753 if (x == VPB_UNBUSIED) { 754 vm_page_unlock(m); 755 return; 756 } 757 if ((x & VPB_BIT_WAITERS) == 0 && 758 !atomic_cmpset_int(&m->busy_lock, x, x | VPB_BIT_WAITERS)) { 759 vm_page_unlock(m); 760 return; 761 } 762 msleep(m, vm_page_lockptr(m), PVM | PDROP, wmesg, 0); 763 } 764 765 /* 766 * vm_page_trysbusy: 767 * 768 * Try to shared busy a page. 769 * If the operation succeeds 1 is returned otherwise 0. 770 * The operation never sleeps. 771 */ 772 int 773 vm_page_trysbusy(vm_page_t m) 774 { 775 u_int x; 776 777 for (;;) { 778 x = m->busy_lock; 779 if ((x & VPB_BIT_SHARED) == 0) 780 return (0); 781 if (atomic_cmpset_acq_int(&m->busy_lock, x, x + VPB_ONE_SHARER)) 782 return (1); 783 } 784 } 785 786 static void 787 vm_page_xunbusy_locked(vm_page_t m) 788 { 789 790 vm_page_assert_xbusied(m); 791 vm_page_assert_locked(m); 792 793 atomic_store_rel_int(&m->busy_lock, VPB_UNBUSIED); 794 /* There is a waiter, do wakeup() instead of vm_page_flash(). */ 795 wakeup(m); 796 } 797 798 static void 799 vm_page_xunbusy_maybelocked(vm_page_t m) 800 { 801 bool lockacq; 802 803 vm_page_assert_xbusied(m); 804 805 /* 806 * Fast path for unbusy. If it succeeds, we know that there 807 * are no waiters, so we do not need a wakeup. 808 */ 809 if (atomic_cmpset_rel_int(&m->busy_lock, VPB_SINGLE_EXCLUSIVER, 810 VPB_UNBUSIED)) 811 return; 812 813 lockacq = !mtx_owned(vm_page_lockptr(m)); 814 if (lockacq) 815 vm_page_lock(m); 816 vm_page_xunbusy_locked(m); 817 if (lockacq) 818 vm_page_unlock(m); 819 } 820 821 /* 822 * vm_page_xunbusy_hard: 823 * 824 * Called after the first try the exclusive unbusy of a page failed. 825 * It is assumed that the waiters bit is on. 826 */ 827 void 828 vm_page_xunbusy_hard(vm_page_t m) 829 { 830 831 vm_page_assert_xbusied(m); 832 833 vm_page_lock(m); 834 vm_page_xunbusy_locked(m); 835 vm_page_unlock(m); 836 } 837 838 /* 839 * vm_page_flash: 840 * 841 * Wakeup anyone waiting for the page. 842 * The ownership bits do not change. 843 * 844 * The given page must be locked. 845 */ 846 void 847 vm_page_flash(vm_page_t m) 848 { 849 u_int x; 850 851 vm_page_lock_assert(m, MA_OWNED); 852 853 for (;;) { 854 x = m->busy_lock; 855 if ((x & VPB_BIT_WAITERS) == 0) 856 return; 857 if (atomic_cmpset_int(&m->busy_lock, x, 858 x & (~VPB_BIT_WAITERS))) 859 break; 860 } 861 wakeup(m); 862 } 863 864 /* 865 * Keep page from being freed by the page daemon 866 * much of the same effect as wiring, except much lower 867 * overhead and should be used only for *very* temporary 868 * holding ("wiring"). 869 */ 870 void 871 vm_page_hold(vm_page_t mem) 872 { 873 874 vm_page_lock_assert(mem, MA_OWNED); 875 mem->hold_count++; 876 } 877 878 void 879 vm_page_unhold(vm_page_t mem) 880 { 881 882 vm_page_lock_assert(mem, MA_OWNED); 883 KASSERT(mem->hold_count >= 1, ("vm_page_unhold: hold count < 0!!!")); 884 --mem->hold_count; 885 if (mem->hold_count == 0 && (mem->flags & PG_UNHOLDFREE) != 0) 886 vm_page_free_toq(mem); 887 } 888 889 /* 890 * vm_page_unhold_pages: 891 * 892 * Unhold each of the pages that is referenced by the given array. 893 */ 894 void 895 vm_page_unhold_pages(vm_page_t *ma, int count) 896 { 897 struct mtx *mtx, *new_mtx; 898 899 mtx = NULL; 900 for (; count != 0; count--) { 901 /* 902 * Avoid releasing and reacquiring the same page lock. 903 */ 904 new_mtx = vm_page_lockptr(*ma); 905 if (mtx != new_mtx) { 906 if (mtx != NULL) 907 mtx_unlock(mtx); 908 mtx = new_mtx; 909 mtx_lock(mtx); 910 } 911 vm_page_unhold(*ma); 912 ma++; 913 } 914 if (mtx != NULL) 915 mtx_unlock(mtx); 916 } 917 918 vm_page_t 919 PHYS_TO_VM_PAGE(vm_paddr_t pa) 920 { 921 vm_page_t m; 922 923 #ifdef VM_PHYSSEG_SPARSE 924 m = vm_phys_paddr_to_vm_page(pa); 925 if (m == NULL) 926 m = vm_phys_fictitious_to_vm_page(pa); 927 return (m); 928 #elif defined(VM_PHYSSEG_DENSE) 929 long pi; 930 931 pi = atop(pa); 932 if (pi >= first_page && (pi - first_page) < vm_page_array_size) { 933 m = &vm_page_array[pi - first_page]; 934 return (m); 935 } 936 return (vm_phys_fictitious_to_vm_page(pa)); 937 #else 938 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." 939 #endif 940 } 941 942 /* 943 * vm_page_getfake: 944 * 945 * Create a fictitious page with the specified physical address and 946 * memory attribute. The memory attribute is the only the machine- 947 * dependent aspect of a fictitious page that must be initialized. 948 */ 949 vm_page_t 950 vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr) 951 { 952 vm_page_t m; 953 954 m = uma_zalloc(fakepg_zone, M_WAITOK | M_ZERO); 955 vm_page_initfake(m, paddr, memattr); 956 return (m); 957 } 958 959 void 960 vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) 961 { 962 963 if ((m->flags & PG_FICTITIOUS) != 0) { 964 /* 965 * The page's memattr might have changed since the 966 * previous initialization. Update the pmap to the 967 * new memattr. 968 */ 969 goto memattr; 970 } 971 m->phys_addr = paddr; 972 m->queue = PQ_NONE; 973 /* Fictitious pages don't use "segind". */ 974 m->flags = PG_FICTITIOUS; 975 /* Fictitious pages don't use "order" or "pool". */ 976 m->oflags = VPO_UNMANAGED; 977 m->busy_lock = VPB_SINGLE_EXCLUSIVER; 978 m->wire_count = 1; 979 pmap_page_init(m); 980 memattr: 981 pmap_page_set_memattr(m, memattr); 982 } 983 984 /* 985 * vm_page_putfake: 986 * 987 * Release a fictitious page. 988 */ 989 void 990 vm_page_putfake(vm_page_t m) 991 { 992 993 KASSERT((m->oflags & VPO_UNMANAGED) != 0, ("managed %p", m)); 994 KASSERT((m->flags & PG_FICTITIOUS) != 0, 995 ("vm_page_putfake: bad page %p", m)); 996 uma_zfree(fakepg_zone, m); 997 } 998 999 /* 1000 * vm_page_updatefake: 1001 * 1002 * Update the given fictitious page to the specified physical address and 1003 * memory attribute. 1004 */ 1005 void 1006 vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) 1007 { 1008 1009 KASSERT((m->flags & PG_FICTITIOUS) != 0, 1010 ("vm_page_updatefake: bad page %p", m)); 1011 m->phys_addr = paddr; 1012 pmap_page_set_memattr(m, memattr); 1013 } 1014 1015 /* 1016 * vm_page_free: 1017 * 1018 * Free a page. 1019 */ 1020 void 1021 vm_page_free(vm_page_t m) 1022 { 1023 1024 m->flags &= ~PG_ZERO; 1025 vm_page_free_toq(m); 1026 } 1027 1028 /* 1029 * vm_page_free_zero: 1030 * 1031 * Free a page to the zerod-pages queue 1032 */ 1033 void 1034 vm_page_free_zero(vm_page_t m) 1035 { 1036 1037 m->flags |= PG_ZERO; 1038 vm_page_free_toq(m); 1039 } 1040 1041 /* 1042 * Unbusy and handle the page queueing for a page from a getpages request that 1043 * was optionally read ahead or behind. 1044 */ 1045 void 1046 vm_page_readahead_finish(vm_page_t m) 1047 { 1048 1049 /* We shouldn't put invalid pages on queues. */ 1050 KASSERT(m->valid != 0, ("%s: %p is invalid", __func__, m)); 1051 1052 /* 1053 * Since the page is not the actually needed one, whether it should 1054 * be activated or deactivated is not obvious. Empirical results 1055 * have shown that deactivating the page is usually the best choice, 1056 * unless the page is wanted by another thread. 1057 */ 1058 vm_page_lock(m); 1059 if ((m->busy_lock & VPB_BIT_WAITERS) != 0) 1060 vm_page_activate(m); 1061 else 1062 vm_page_deactivate(m); 1063 vm_page_unlock(m); 1064 vm_page_xunbusy(m); 1065 } 1066 1067 /* 1068 * vm_page_sleep_if_busy: 1069 * 1070 * Sleep and release the page queues lock if the page is busied. 1071 * Returns TRUE if the thread slept. 1072 * 1073 * The given page must be unlocked and object containing it must 1074 * be locked. 1075 */ 1076 int 1077 vm_page_sleep_if_busy(vm_page_t m, const char *msg) 1078 { 1079 vm_object_t obj; 1080 1081 vm_page_lock_assert(m, MA_NOTOWNED); 1082 VM_OBJECT_ASSERT_WLOCKED(m->object); 1083 1084 if (vm_page_busied(m)) { 1085 /* 1086 * The page-specific object must be cached because page 1087 * identity can change during the sleep, causing the 1088 * re-lock of a different object. 1089 * It is assumed that a reference to the object is already 1090 * held by the callers. 1091 */ 1092 obj = m->object; 1093 vm_page_lock(m); 1094 VM_OBJECT_WUNLOCK(obj); 1095 vm_page_busy_sleep(m, msg); 1096 VM_OBJECT_WLOCK(obj); 1097 return (TRUE); 1098 } 1099 return (FALSE); 1100 } 1101 1102 /* 1103 * vm_page_dirty_KBI: [ internal use only ] 1104 * 1105 * Set all bits in the page's dirty field. 1106 * 1107 * The object containing the specified page must be locked if the 1108 * call is made from the machine-independent layer. 1109 * 1110 * See vm_page_clear_dirty_mask(). 1111 * 1112 * This function should only be called by vm_page_dirty(). 1113 */ 1114 void 1115 vm_page_dirty_KBI(vm_page_t m) 1116 { 1117 1118 /* These assertions refer to this operation by its public name. */ 1119 KASSERT((m->flags & PG_CACHED) == 0, 1120 ("vm_page_dirty: page in cache!")); 1121 KASSERT(m->valid == VM_PAGE_BITS_ALL, 1122 ("vm_page_dirty: page is invalid!")); 1123 m->dirty = VM_PAGE_BITS_ALL; 1124 } 1125 1126 /* 1127 * vm_page_insert: [ internal use only ] 1128 * 1129 * Inserts the given mem entry into the object and object list. 1130 * 1131 * The object must be locked. 1132 */ 1133 int 1134 vm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex) 1135 { 1136 vm_page_t mpred; 1137 1138 VM_OBJECT_ASSERT_WLOCKED(object); 1139 mpred = vm_radix_lookup_le(&object->rtree, pindex); 1140 return (vm_page_insert_after(m, object, pindex, mpred)); 1141 } 1142 1143 /* 1144 * vm_page_insert_after: 1145 * 1146 * Inserts the page "m" into the specified object at offset "pindex". 1147 * 1148 * The page "mpred" must immediately precede the offset "pindex" within 1149 * the specified object. 1150 * 1151 * The object must be locked. 1152 */ 1153 static int 1154 vm_page_insert_after(vm_page_t m, vm_object_t object, vm_pindex_t pindex, 1155 vm_page_t mpred) 1156 { 1157 vm_page_t msucc; 1158 1159 VM_OBJECT_ASSERT_WLOCKED(object); 1160 KASSERT(m->object == NULL, 1161 ("vm_page_insert_after: page already inserted")); 1162 if (mpred != NULL) { 1163 KASSERT(mpred->object == object, 1164 ("vm_page_insert_after: object doesn't contain mpred")); 1165 KASSERT(mpred->pindex < pindex, 1166 ("vm_page_insert_after: mpred doesn't precede pindex")); 1167 msucc = TAILQ_NEXT(mpred, listq); 1168 } else 1169 msucc = TAILQ_FIRST(&object->memq); 1170 if (msucc != NULL) 1171 KASSERT(msucc->pindex > pindex, 1172 ("vm_page_insert_after: msucc doesn't succeed pindex")); 1173 1174 /* 1175 * Record the object/offset pair in this page 1176 */ 1177 m->object = object; 1178 m->pindex = pindex; 1179 1180 /* 1181 * Now link into the object's ordered list of backed pages. 1182 */ 1183 if (vm_radix_insert(&object->rtree, m)) { 1184 m->object = NULL; 1185 m->pindex = 0; 1186 return (1); 1187 } 1188 vm_page_insert_radixdone(m, object, mpred); 1189 return (0); 1190 } 1191 1192 /* 1193 * vm_page_insert_radixdone: 1194 * 1195 * Complete page "m" insertion into the specified object after the 1196 * radix trie hooking. 1197 * 1198 * The page "mpred" must precede the offset "m->pindex" within the 1199 * specified object. 1200 * 1201 * The object must be locked. 1202 */ 1203 static void 1204 vm_page_insert_radixdone(vm_page_t m, vm_object_t object, vm_page_t mpred) 1205 { 1206 1207 VM_OBJECT_ASSERT_WLOCKED(object); 1208 KASSERT(object != NULL && m->object == object, 1209 ("vm_page_insert_radixdone: page %p has inconsistent object", m)); 1210 if (mpred != NULL) { 1211 KASSERT(mpred->object == object, 1212 ("vm_page_insert_after: object doesn't contain mpred")); 1213 KASSERT(mpred->pindex < m->pindex, 1214 ("vm_page_insert_after: mpred doesn't precede pindex")); 1215 } 1216 1217 if (mpred != NULL) 1218 TAILQ_INSERT_AFTER(&object->memq, mpred, m, listq); 1219 else 1220 TAILQ_INSERT_HEAD(&object->memq, m, listq); 1221 1222 /* 1223 * Show that the object has one more resident page. 1224 */ 1225 object->resident_page_count++; 1226 1227 /* 1228 * Hold the vnode until the last page is released. 1229 */ 1230 if (object->resident_page_count == 1 && object->type == OBJT_VNODE) 1231 vhold(object->handle); 1232 1233 /* 1234 * Since we are inserting a new and possibly dirty page, 1235 * update the object's OBJ_MIGHTBEDIRTY flag. 1236 */ 1237 if (pmap_page_is_write_mapped(m)) 1238 vm_object_set_writeable_dirty(object); 1239 } 1240 1241 /* 1242 * vm_page_remove: 1243 * 1244 * Removes the given mem entry from the object/offset-page 1245 * table and the object page list, but do not invalidate/terminate 1246 * the backing store. 1247 * 1248 * The object must be locked. The page must be locked if it is managed. 1249 */ 1250 void 1251 vm_page_remove(vm_page_t m) 1252 { 1253 vm_object_t object; 1254 1255 if ((m->oflags & VPO_UNMANAGED) == 0) 1256 vm_page_assert_locked(m); 1257 if ((object = m->object) == NULL) 1258 return; 1259 VM_OBJECT_ASSERT_WLOCKED(object); 1260 if (vm_page_xbusied(m)) 1261 vm_page_xunbusy_maybelocked(m); 1262 1263 /* 1264 * Now remove from the object's list of backed pages. 1265 */ 1266 vm_radix_remove(&object->rtree, m->pindex); 1267 TAILQ_REMOVE(&object->memq, m, listq); 1268 1269 /* 1270 * And show that the object has one fewer resident page. 1271 */ 1272 object->resident_page_count--; 1273 1274 /* 1275 * The vnode may now be recycled. 1276 */ 1277 if (object->resident_page_count == 0 && object->type == OBJT_VNODE) 1278 vdrop(object->handle); 1279 1280 m->object = NULL; 1281 } 1282 1283 /* 1284 * vm_page_lookup: 1285 * 1286 * Returns the page associated with the object/offset 1287 * pair specified; if none is found, NULL is returned. 1288 * 1289 * The object must be locked. 1290 */ 1291 vm_page_t 1292 vm_page_lookup(vm_object_t object, vm_pindex_t pindex) 1293 { 1294 1295 VM_OBJECT_ASSERT_LOCKED(object); 1296 return (vm_radix_lookup(&object->rtree, pindex)); 1297 } 1298 1299 /* 1300 * vm_page_find_least: 1301 * 1302 * Returns the page associated with the object with least pindex 1303 * greater than or equal to the parameter pindex, or NULL. 1304 * 1305 * The object must be locked. 1306 */ 1307 vm_page_t 1308 vm_page_find_least(vm_object_t object, vm_pindex_t pindex) 1309 { 1310 vm_page_t m; 1311 1312 VM_OBJECT_ASSERT_LOCKED(object); 1313 if ((m = TAILQ_FIRST(&object->memq)) != NULL && m->pindex < pindex) 1314 m = vm_radix_lookup_ge(&object->rtree, pindex); 1315 return (m); 1316 } 1317 1318 /* 1319 * Returns the given page's successor (by pindex) within the object if it is 1320 * resident; if none is found, NULL is returned. 1321 * 1322 * The object must be locked. 1323 */ 1324 vm_page_t 1325 vm_page_next(vm_page_t m) 1326 { 1327 vm_page_t next; 1328 1329 VM_OBJECT_ASSERT_LOCKED(m->object); 1330 if ((next = TAILQ_NEXT(m, listq)) != NULL && 1331 next->pindex != m->pindex + 1) 1332 next = NULL; 1333 return (next); 1334 } 1335 1336 /* 1337 * Returns the given page's predecessor (by pindex) within the object if it is 1338 * resident; if none is found, NULL is returned. 1339 * 1340 * The object must be locked. 1341 */ 1342 vm_page_t 1343 vm_page_prev(vm_page_t m) 1344 { 1345 vm_page_t prev; 1346 1347 VM_OBJECT_ASSERT_LOCKED(m->object); 1348 if ((prev = TAILQ_PREV(m, pglist, listq)) != NULL && 1349 prev->pindex != m->pindex - 1) 1350 prev = NULL; 1351 return (prev); 1352 } 1353 1354 /* 1355 * Uses the page mnew as a replacement for an existing page at index 1356 * pindex which must be already present in the object. 1357 * 1358 * The existing page must not be on a paging queue. 1359 */ 1360 vm_page_t 1361 vm_page_replace(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex) 1362 { 1363 vm_page_t mold; 1364 1365 VM_OBJECT_ASSERT_WLOCKED(object); 1366 KASSERT(mnew->object == NULL, 1367 ("vm_page_replace: page already in object")); 1368 1369 /* 1370 * This function mostly follows vm_page_insert() and 1371 * vm_page_remove() without the radix, object count and vnode 1372 * dance. Double check such functions for more comments. 1373 */ 1374 1375 mnew->object = object; 1376 mnew->pindex = pindex; 1377 mold = vm_radix_replace(&object->rtree, mnew); 1378 KASSERT(mold->queue == PQ_NONE, 1379 ("vm_page_replace: mold is on a paging queue")); 1380 1381 /* Keep the resident page list in sorted order. */ 1382 TAILQ_INSERT_AFTER(&object->memq, mold, mnew, listq); 1383 TAILQ_REMOVE(&object->memq, mold, listq); 1384 1385 mold->object = NULL; 1386 vm_page_xunbusy_maybelocked(mold); 1387 1388 /* 1389 * The object's resident_page_count does not change because we have 1390 * swapped one page for another, but OBJ_MIGHTBEDIRTY. 1391 */ 1392 if (pmap_page_is_write_mapped(mnew)) 1393 vm_object_set_writeable_dirty(object); 1394 return (mold); 1395 } 1396 1397 /* 1398 * vm_page_rename: 1399 * 1400 * Move the given memory entry from its 1401 * current object to the specified target object/offset. 1402 * 1403 * Note: swap associated with the page must be invalidated by the move. We 1404 * have to do this for several reasons: (1) we aren't freeing the 1405 * page, (2) we are dirtying the page, (3) the VM system is probably 1406 * moving the page from object A to B, and will then later move 1407 * the backing store from A to B and we can't have a conflict. 1408 * 1409 * Note: we *always* dirty the page. It is necessary both for the 1410 * fact that we moved it, and because we may be invalidating 1411 * swap. If the page is on the cache, we have to deactivate it 1412 * or vm_page_dirty() will panic. Dirty pages are not allowed 1413 * on the cache. 1414 * 1415 * The objects must be locked. 1416 */ 1417 int 1418 vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex) 1419 { 1420 vm_page_t mpred; 1421 vm_pindex_t opidx; 1422 1423 VM_OBJECT_ASSERT_WLOCKED(new_object); 1424 1425 mpred = vm_radix_lookup_le(&new_object->rtree, new_pindex); 1426 KASSERT(mpred == NULL || mpred->pindex != new_pindex, 1427 ("vm_page_rename: pindex already renamed")); 1428 1429 /* 1430 * Create a custom version of vm_page_insert() which does not depend 1431 * by m_prev and can cheat on the implementation aspects of the 1432 * function. 1433 */ 1434 opidx = m->pindex; 1435 m->pindex = new_pindex; 1436 if (vm_radix_insert(&new_object->rtree, m)) { 1437 m->pindex = opidx; 1438 return (1); 1439 } 1440 1441 /* 1442 * The operation cannot fail anymore. The removal must happen before 1443 * the listq iterator is tainted. 1444 */ 1445 m->pindex = opidx; 1446 vm_page_lock(m); 1447 vm_page_remove(m); 1448 1449 /* Return back to the new pindex to complete vm_page_insert(). */ 1450 m->pindex = new_pindex; 1451 m->object = new_object; 1452 vm_page_unlock(m); 1453 vm_page_insert_radixdone(m, new_object, mpred); 1454 vm_page_dirty(m); 1455 return (0); 1456 } 1457 1458 /* 1459 * Convert all of the given object's cached pages that have a 1460 * pindex within the given range into free pages. If the value 1461 * zero is given for "end", then the range's upper bound is 1462 * infinity. If the given object is backed by a vnode and it 1463 * transitions from having one or more cached pages to none, the 1464 * vnode's hold count is reduced. 1465 */ 1466 void 1467 vm_page_cache_free(vm_object_t object, vm_pindex_t start, vm_pindex_t end) 1468 { 1469 vm_page_t m; 1470 boolean_t empty; 1471 1472 mtx_lock(&vm_page_queue_free_mtx); 1473 if (__predict_false(vm_radix_is_empty(&object->cache))) { 1474 mtx_unlock(&vm_page_queue_free_mtx); 1475 return; 1476 } 1477 while ((m = vm_radix_lookup_ge(&object->cache, start)) != NULL) { 1478 if (end != 0 && m->pindex >= end) 1479 break; 1480 vm_radix_remove(&object->cache, m->pindex); 1481 vm_page_cache_turn_free(m); 1482 } 1483 empty = vm_radix_is_empty(&object->cache); 1484 mtx_unlock(&vm_page_queue_free_mtx); 1485 if (object->type == OBJT_VNODE && empty) 1486 vdrop(object->handle); 1487 } 1488 1489 /* 1490 * Returns the cached page that is associated with the given 1491 * object and offset. If, however, none exists, returns NULL. 1492 * 1493 * The free page queue must be locked. 1494 */ 1495 static inline vm_page_t 1496 vm_page_cache_lookup(vm_object_t object, vm_pindex_t pindex) 1497 { 1498 1499 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 1500 return (vm_radix_lookup(&object->cache, pindex)); 1501 } 1502 1503 /* 1504 * Remove the given cached page from its containing object's 1505 * collection of cached pages. 1506 * 1507 * The free page queue must be locked. 1508 */ 1509 static void 1510 vm_page_cache_remove(vm_page_t m) 1511 { 1512 1513 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 1514 KASSERT((m->flags & PG_CACHED) != 0, 1515 ("vm_page_cache_remove: page %p is not cached", m)); 1516 vm_radix_remove(&m->object->cache, m->pindex); 1517 m->object = NULL; 1518 vm_cnt.v_cache_count--; 1519 } 1520 1521 /* 1522 * Transfer all of the cached pages with offset greater than or 1523 * equal to 'offidxstart' from the original object's cache to the 1524 * new object's cache. However, any cached pages with offset 1525 * greater than or equal to the new object's size are kept in the 1526 * original object. Initially, the new object's cache must be 1527 * empty. Offset 'offidxstart' in the original object must 1528 * correspond to offset zero in the new object. 1529 * 1530 * The new object must be locked. 1531 */ 1532 void 1533 vm_page_cache_transfer(vm_object_t orig_object, vm_pindex_t offidxstart, 1534 vm_object_t new_object) 1535 { 1536 vm_page_t m; 1537 1538 /* 1539 * Insertion into an object's collection of cached pages 1540 * requires the object to be locked. In contrast, removal does 1541 * not. 1542 */ 1543 VM_OBJECT_ASSERT_WLOCKED(new_object); 1544 KASSERT(vm_radix_is_empty(&new_object->cache), 1545 ("vm_page_cache_transfer: object %p has cached pages", 1546 new_object)); 1547 mtx_lock(&vm_page_queue_free_mtx); 1548 while ((m = vm_radix_lookup_ge(&orig_object->cache, 1549 offidxstart)) != NULL) { 1550 /* 1551 * Transfer all of the pages with offset greater than or 1552 * equal to 'offidxstart' from the original object's 1553 * cache to the new object's cache. 1554 */ 1555 if ((m->pindex - offidxstart) >= new_object->size) 1556 break; 1557 vm_radix_remove(&orig_object->cache, m->pindex); 1558 /* Update the page's object and offset. */ 1559 m->object = new_object; 1560 m->pindex -= offidxstart; 1561 if (vm_radix_insert(&new_object->cache, m)) 1562 vm_page_cache_turn_free(m); 1563 } 1564 mtx_unlock(&vm_page_queue_free_mtx); 1565 } 1566 1567 /* 1568 * Returns TRUE if a cached page is associated with the given object and 1569 * offset, and FALSE otherwise. 1570 * 1571 * The object must be locked. 1572 */ 1573 boolean_t 1574 vm_page_is_cached(vm_object_t object, vm_pindex_t pindex) 1575 { 1576 vm_page_t m; 1577 1578 /* 1579 * Insertion into an object's collection of cached pages requires the 1580 * object to be locked. Therefore, if the object is locked and the 1581 * object's collection is empty, there is no need to acquire the free 1582 * page queues lock in order to prove that the specified page doesn't 1583 * exist. 1584 */ 1585 VM_OBJECT_ASSERT_WLOCKED(object); 1586 if (__predict_true(vm_object_cache_is_empty(object))) 1587 return (FALSE); 1588 mtx_lock(&vm_page_queue_free_mtx); 1589 m = vm_page_cache_lookup(object, pindex); 1590 mtx_unlock(&vm_page_queue_free_mtx); 1591 return (m != NULL); 1592 } 1593 1594 /* 1595 * vm_page_alloc: 1596 * 1597 * Allocate and return a page that is associated with the specified 1598 * object and offset pair. By default, this page is exclusive busied. 1599 * 1600 * The caller must always specify an allocation class. 1601 * 1602 * allocation classes: 1603 * VM_ALLOC_NORMAL normal process request 1604 * VM_ALLOC_SYSTEM system *really* needs a page 1605 * VM_ALLOC_INTERRUPT interrupt time request 1606 * 1607 * optional allocation flags: 1608 * VM_ALLOC_COUNT(number) the number of additional pages that the caller 1609 * intends to allocate 1610 * VM_ALLOC_IFCACHED return page only if it is cached 1611 * VM_ALLOC_IFNOTCACHED return NULL, do not reactivate if the page 1612 * is cached 1613 * VM_ALLOC_NOBUSY do not exclusive busy the page 1614 * VM_ALLOC_NODUMP do not include the page in a kernel core dump 1615 * VM_ALLOC_NOOBJ page is not associated with an object and 1616 * should not be exclusive busy 1617 * VM_ALLOC_SBUSY shared busy the allocated page 1618 * VM_ALLOC_WIRED wire the allocated page 1619 * VM_ALLOC_ZERO prefer a zeroed page 1620 * 1621 * This routine may not sleep. 1622 */ 1623 vm_page_t 1624 vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req) 1625 { 1626 struct vnode *vp = NULL; 1627 vm_object_t m_object; 1628 vm_page_t m, mpred; 1629 int flags, req_class; 1630 1631 mpred = 0; /* XXX: pacify gcc */ 1632 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) && 1633 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) && 1634 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 1635 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 1636 ("vm_page_alloc: inconsistent object(%p)/req(%x)", (void *)object, 1637 req)); 1638 if (object != NULL) 1639 VM_OBJECT_ASSERT_WLOCKED(object); 1640 1641 req_class = req & VM_ALLOC_CLASS_MASK; 1642 1643 /* 1644 * The page daemon is allowed to dig deeper into the free page list. 1645 */ 1646 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 1647 req_class = VM_ALLOC_SYSTEM; 1648 1649 if (object != NULL) { 1650 mpred = vm_radix_lookup_le(&object->rtree, pindex); 1651 KASSERT(mpred == NULL || mpred->pindex != pindex, 1652 ("vm_page_alloc: pindex already allocated")); 1653 } 1654 1655 /* 1656 * The page allocation request can came from consumers which already 1657 * hold the free page queue mutex, like vm_page_insert() in 1658 * vm_page_cache(). 1659 */ 1660 mtx_lock_flags(&vm_page_queue_free_mtx, MTX_RECURSE); 1661 if (vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_free_reserved || 1662 (req_class == VM_ALLOC_SYSTEM && 1663 vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_interrupt_free_min) || 1664 (req_class == VM_ALLOC_INTERRUPT && 1665 vm_cnt.v_free_count + vm_cnt.v_cache_count > 0)) { 1666 /* 1667 * Allocate from the free queue if the number of free pages 1668 * exceeds the minimum for the request class. 1669 */ 1670 if (object != NULL && 1671 (m = vm_page_cache_lookup(object, pindex)) != NULL) { 1672 if ((req & VM_ALLOC_IFNOTCACHED) != 0) { 1673 mtx_unlock(&vm_page_queue_free_mtx); 1674 return (NULL); 1675 } 1676 if (vm_phys_unfree_page(m)) 1677 vm_phys_set_pool(VM_FREEPOOL_DEFAULT, m, 0); 1678 #if VM_NRESERVLEVEL > 0 1679 else if (!vm_reserv_reactivate_page(m)) 1680 #else 1681 else 1682 #endif 1683 panic("vm_page_alloc: cache page %p is missing" 1684 " from the free queue", m); 1685 } else if ((req & VM_ALLOC_IFCACHED) != 0) { 1686 mtx_unlock(&vm_page_queue_free_mtx); 1687 return (NULL); 1688 #if VM_NRESERVLEVEL > 0 1689 } else if (object == NULL || (object->flags & (OBJ_COLORED | 1690 OBJ_FICTITIOUS)) != OBJ_COLORED || (m = 1691 vm_reserv_alloc_page(object, pindex, mpred)) == NULL) { 1692 #else 1693 } else { 1694 #endif 1695 m = vm_phys_alloc_pages(object != NULL ? 1696 VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT, 0); 1697 #if VM_NRESERVLEVEL > 0 1698 if (m == NULL && vm_reserv_reclaim_inactive()) { 1699 m = vm_phys_alloc_pages(object != NULL ? 1700 VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT, 1701 0); 1702 } 1703 #endif 1704 } 1705 } else { 1706 /* 1707 * Not allocatable, give up. 1708 */ 1709 mtx_unlock(&vm_page_queue_free_mtx); 1710 atomic_add_int(&vm_pageout_deficit, 1711 max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1)); 1712 pagedaemon_wakeup(); 1713 return (NULL); 1714 } 1715 1716 /* 1717 * At this point we had better have found a good page. 1718 */ 1719 KASSERT(m != NULL, ("vm_page_alloc: missing page")); 1720 KASSERT(m->queue == PQ_NONE, 1721 ("vm_page_alloc: page %p has unexpected queue %d", m, m->queue)); 1722 KASSERT(m->wire_count == 0, ("vm_page_alloc: page %p is wired", m)); 1723 KASSERT(m->hold_count == 0, ("vm_page_alloc: page %p is held", m)); 1724 KASSERT(!vm_page_busied(m), ("vm_page_alloc: page %p is busy", m)); 1725 KASSERT(m->dirty == 0, ("vm_page_alloc: page %p is dirty", m)); 1726 KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, 1727 ("vm_page_alloc: page %p has unexpected memattr %d", m, 1728 pmap_page_get_memattr(m))); 1729 if ((m->flags & PG_CACHED) != 0) { 1730 KASSERT((m->flags & PG_ZERO) == 0, 1731 ("vm_page_alloc: cached page %p is PG_ZERO", m)); 1732 KASSERT(m->valid != 0, 1733 ("vm_page_alloc: cached page %p is invalid", m)); 1734 if (m->object == object && m->pindex == pindex) 1735 vm_cnt.v_reactivated++; 1736 else 1737 m->valid = 0; 1738 m_object = m->object; 1739 vm_page_cache_remove(m); 1740 if (m_object->type == OBJT_VNODE && 1741 vm_object_cache_is_empty(m_object)) 1742 vp = m_object->handle; 1743 } else { 1744 KASSERT(m->valid == 0, 1745 ("vm_page_alloc: free page %p is valid", m)); 1746 vm_phys_freecnt_adj(m, -1); 1747 } 1748 mtx_unlock(&vm_page_queue_free_mtx); 1749 1750 /* 1751 * Initialize the page. Only the PG_ZERO flag is inherited. 1752 */ 1753 flags = 0; 1754 if ((req & VM_ALLOC_ZERO) != 0) 1755 flags = PG_ZERO; 1756 flags &= m->flags; 1757 if ((req & VM_ALLOC_NODUMP) != 0) 1758 flags |= PG_NODUMP; 1759 m->flags = flags; 1760 m->aflags = 0; 1761 m->oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ? 1762 VPO_UNMANAGED : 0; 1763 m->busy_lock = VPB_UNBUSIED; 1764 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0) 1765 m->busy_lock = VPB_SINGLE_EXCLUSIVER; 1766 if ((req & VM_ALLOC_SBUSY) != 0) 1767 m->busy_lock = VPB_SHARERS_WORD(1); 1768 if (req & VM_ALLOC_WIRED) { 1769 /* 1770 * The page lock is not required for wiring a page until that 1771 * page is inserted into the object. 1772 */ 1773 atomic_add_int(&vm_cnt.v_wire_count, 1); 1774 m->wire_count = 1; 1775 } 1776 m->act_count = 0; 1777 1778 if (object != NULL) { 1779 if (vm_page_insert_after(m, object, pindex, mpred)) { 1780 /* See the comment below about hold count. */ 1781 if (vp != NULL) 1782 vdrop(vp); 1783 pagedaemon_wakeup(); 1784 if (req & VM_ALLOC_WIRED) { 1785 atomic_subtract_int(&vm_cnt.v_wire_count, 1); 1786 m->wire_count = 0; 1787 } 1788 m->object = NULL; 1789 m->oflags = VPO_UNMANAGED; 1790 m->busy_lock = VPB_UNBUSIED; 1791 vm_page_free(m); 1792 return (NULL); 1793 } 1794 1795 /* Ignore device objects; the pager sets "memattr" for them. */ 1796 if (object->memattr != VM_MEMATTR_DEFAULT && 1797 (object->flags & OBJ_FICTITIOUS) == 0) 1798 pmap_page_set_memattr(m, object->memattr); 1799 } else 1800 m->pindex = pindex; 1801 1802 /* 1803 * The following call to vdrop() must come after the above call 1804 * to vm_page_insert() in case both affect the same object and 1805 * vnode. Otherwise, the affected vnode's hold count could 1806 * temporarily become zero. 1807 */ 1808 if (vp != NULL) 1809 vdrop(vp); 1810 1811 /* 1812 * Don't wakeup too often - wakeup the pageout daemon when 1813 * we would be nearly out of memory. 1814 */ 1815 if (vm_paging_needed()) 1816 pagedaemon_wakeup(); 1817 1818 return (m); 1819 } 1820 1821 static void 1822 vm_page_alloc_contig_vdrop(struct spglist *lst) 1823 { 1824 1825 while (!SLIST_EMPTY(lst)) { 1826 vdrop((struct vnode *)SLIST_FIRST(lst)-> plinks.s.pv); 1827 SLIST_REMOVE_HEAD(lst, plinks.s.ss); 1828 } 1829 } 1830 1831 /* 1832 * vm_page_alloc_contig: 1833 * 1834 * Allocate a contiguous set of physical pages of the given size "npages" 1835 * from the free lists. All of the physical pages must be at or above 1836 * the given physical address "low" and below the given physical address 1837 * "high". The given value "alignment" determines the alignment of the 1838 * first physical page in the set. If the given value "boundary" is 1839 * non-zero, then the set of physical pages cannot cross any physical 1840 * address boundary that is a multiple of that value. Both "alignment" 1841 * and "boundary" must be a power of two. 1842 * 1843 * If the specified memory attribute, "memattr", is VM_MEMATTR_DEFAULT, 1844 * then the memory attribute setting for the physical pages is configured 1845 * to the object's memory attribute setting. Otherwise, the memory 1846 * attribute setting for the physical pages is configured to "memattr", 1847 * overriding the object's memory attribute setting. However, if the 1848 * object's memory attribute setting is not VM_MEMATTR_DEFAULT, then the 1849 * memory attribute setting for the physical pages cannot be configured 1850 * to VM_MEMATTR_DEFAULT. 1851 * 1852 * The caller must always specify an allocation class. 1853 * 1854 * allocation classes: 1855 * VM_ALLOC_NORMAL normal process request 1856 * VM_ALLOC_SYSTEM system *really* needs a page 1857 * VM_ALLOC_INTERRUPT interrupt time request 1858 * 1859 * optional allocation flags: 1860 * VM_ALLOC_NOBUSY do not exclusive busy the page 1861 * VM_ALLOC_NODUMP do not include the page in a kernel core dump 1862 * VM_ALLOC_NOOBJ page is not associated with an object and 1863 * should not be exclusive busy 1864 * VM_ALLOC_SBUSY shared busy the allocated page 1865 * VM_ALLOC_WIRED wire the allocated page 1866 * VM_ALLOC_ZERO prefer a zeroed page 1867 * 1868 * This routine may not sleep. 1869 */ 1870 vm_page_t 1871 vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req, 1872 u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, 1873 vm_paddr_t boundary, vm_memattr_t memattr) 1874 { 1875 struct vnode *drop; 1876 struct spglist deferred_vdrop_list; 1877 vm_page_t m, m_tmp, m_ret; 1878 u_int flags; 1879 int req_class; 1880 1881 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) && 1882 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) && 1883 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 1884 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 1885 ("vm_page_alloc: inconsistent object(%p)/req(%x)", (void *)object, 1886 req)); 1887 if (object != NULL) { 1888 VM_OBJECT_ASSERT_WLOCKED(object); 1889 KASSERT(object->type == OBJT_PHYS, 1890 ("vm_page_alloc_contig: object %p isn't OBJT_PHYS", 1891 object)); 1892 } 1893 KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero")); 1894 req_class = req & VM_ALLOC_CLASS_MASK; 1895 1896 /* 1897 * The page daemon is allowed to dig deeper into the free page list. 1898 */ 1899 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 1900 req_class = VM_ALLOC_SYSTEM; 1901 1902 SLIST_INIT(&deferred_vdrop_list); 1903 mtx_lock(&vm_page_queue_free_mtx); 1904 if (vm_cnt.v_free_count + vm_cnt.v_cache_count >= npages + 1905 vm_cnt.v_free_reserved || (req_class == VM_ALLOC_SYSTEM && 1906 vm_cnt.v_free_count + vm_cnt.v_cache_count >= npages + 1907 vm_cnt.v_interrupt_free_min) || (req_class == VM_ALLOC_INTERRUPT && 1908 vm_cnt.v_free_count + vm_cnt.v_cache_count >= npages)) { 1909 #if VM_NRESERVLEVEL > 0 1910 retry: 1911 if (object == NULL || (object->flags & OBJ_COLORED) == 0 || 1912 (m_ret = vm_reserv_alloc_contig(object, pindex, npages, 1913 low, high, alignment, boundary)) == NULL) 1914 #endif 1915 m_ret = vm_phys_alloc_contig(npages, low, high, 1916 alignment, boundary); 1917 } else { 1918 mtx_unlock(&vm_page_queue_free_mtx); 1919 atomic_add_int(&vm_pageout_deficit, npages); 1920 pagedaemon_wakeup(); 1921 return (NULL); 1922 } 1923 if (m_ret != NULL) 1924 for (m = m_ret; m < &m_ret[npages]; m++) { 1925 drop = vm_page_alloc_init(m); 1926 if (drop != NULL) { 1927 /* 1928 * Enqueue the vnode for deferred vdrop(). 1929 */ 1930 m->plinks.s.pv = drop; 1931 SLIST_INSERT_HEAD(&deferred_vdrop_list, m, 1932 plinks.s.ss); 1933 } 1934 } 1935 else { 1936 #if VM_NRESERVLEVEL > 0 1937 if (vm_reserv_reclaim_contig(npages, low, high, alignment, 1938 boundary)) 1939 goto retry; 1940 #endif 1941 } 1942 mtx_unlock(&vm_page_queue_free_mtx); 1943 if (m_ret == NULL) 1944 return (NULL); 1945 1946 /* 1947 * Initialize the pages. Only the PG_ZERO flag is inherited. 1948 */ 1949 flags = 0; 1950 if ((req & VM_ALLOC_ZERO) != 0) 1951 flags = PG_ZERO; 1952 if ((req & VM_ALLOC_NODUMP) != 0) 1953 flags |= PG_NODUMP; 1954 if ((req & VM_ALLOC_WIRED) != 0) 1955 atomic_add_int(&vm_cnt.v_wire_count, npages); 1956 if (object != NULL) { 1957 if (object->memattr != VM_MEMATTR_DEFAULT && 1958 memattr == VM_MEMATTR_DEFAULT) 1959 memattr = object->memattr; 1960 } 1961 for (m = m_ret; m < &m_ret[npages]; m++) { 1962 m->aflags = 0; 1963 m->flags = (m->flags | PG_NODUMP) & flags; 1964 m->busy_lock = VPB_UNBUSIED; 1965 if (object != NULL) { 1966 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0) 1967 m->busy_lock = VPB_SINGLE_EXCLUSIVER; 1968 if ((req & VM_ALLOC_SBUSY) != 0) 1969 m->busy_lock = VPB_SHARERS_WORD(1); 1970 } 1971 if ((req & VM_ALLOC_WIRED) != 0) 1972 m->wire_count = 1; 1973 /* Unmanaged pages don't use "act_count". */ 1974 m->oflags = VPO_UNMANAGED; 1975 if (object != NULL) { 1976 if (vm_page_insert(m, object, pindex)) { 1977 vm_page_alloc_contig_vdrop( 1978 &deferred_vdrop_list); 1979 if (vm_paging_needed()) 1980 pagedaemon_wakeup(); 1981 if ((req & VM_ALLOC_WIRED) != 0) 1982 atomic_subtract_int(&vm_cnt.v_wire_count, 1983 npages); 1984 for (m_tmp = m, m = m_ret; 1985 m < &m_ret[npages]; m++) { 1986 if ((req & VM_ALLOC_WIRED) != 0) 1987 m->wire_count = 0; 1988 if (m >= m_tmp) { 1989 m->object = NULL; 1990 m->oflags |= VPO_UNMANAGED; 1991 } 1992 m->busy_lock = VPB_UNBUSIED; 1993 vm_page_free(m); 1994 } 1995 return (NULL); 1996 } 1997 } else 1998 m->pindex = pindex; 1999 if (memattr != VM_MEMATTR_DEFAULT) 2000 pmap_page_set_memattr(m, memattr); 2001 pindex++; 2002 } 2003 vm_page_alloc_contig_vdrop(&deferred_vdrop_list); 2004 if (vm_paging_needed()) 2005 pagedaemon_wakeup(); 2006 return (m_ret); 2007 } 2008 2009 /* 2010 * Initialize a page that has been freshly dequeued from a freelist. 2011 * The caller has to drop the vnode returned, if it is not NULL. 2012 * 2013 * This function may only be used to initialize unmanaged pages. 2014 * 2015 * To be called with vm_page_queue_free_mtx held. 2016 */ 2017 static struct vnode * 2018 vm_page_alloc_init(vm_page_t m) 2019 { 2020 struct vnode *drop; 2021 vm_object_t m_object; 2022 2023 KASSERT(m->queue == PQ_NONE, 2024 ("vm_page_alloc_init: page %p has unexpected queue %d", 2025 m, m->queue)); 2026 KASSERT(m->wire_count == 0, 2027 ("vm_page_alloc_init: page %p is wired", m)); 2028 KASSERT(m->hold_count == 0, 2029 ("vm_page_alloc_init: page %p is held", m)); 2030 KASSERT(!vm_page_busied(m), 2031 ("vm_page_alloc_init: page %p is busy", m)); 2032 KASSERT(m->dirty == 0, 2033 ("vm_page_alloc_init: page %p is dirty", m)); 2034 KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, 2035 ("vm_page_alloc_init: page %p has unexpected memattr %d", 2036 m, pmap_page_get_memattr(m))); 2037 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 2038 drop = NULL; 2039 if ((m->flags & PG_CACHED) != 0) { 2040 KASSERT((m->flags & PG_ZERO) == 0, 2041 ("vm_page_alloc_init: cached page %p is PG_ZERO", m)); 2042 m->valid = 0; 2043 m_object = m->object; 2044 vm_page_cache_remove(m); 2045 if (m_object->type == OBJT_VNODE && 2046 vm_object_cache_is_empty(m_object)) 2047 drop = m_object->handle; 2048 } else { 2049 KASSERT(m->valid == 0, 2050 ("vm_page_alloc_init: free page %p is valid", m)); 2051 vm_phys_freecnt_adj(m, -1); 2052 } 2053 return (drop); 2054 } 2055 2056 /* 2057 * vm_page_alloc_freelist: 2058 * 2059 * Allocate a physical page from the specified free page list. 2060 * 2061 * The caller must always specify an allocation class. 2062 * 2063 * allocation classes: 2064 * VM_ALLOC_NORMAL normal process request 2065 * VM_ALLOC_SYSTEM system *really* needs a page 2066 * VM_ALLOC_INTERRUPT interrupt time request 2067 * 2068 * optional allocation flags: 2069 * VM_ALLOC_COUNT(number) the number of additional pages that the caller 2070 * intends to allocate 2071 * VM_ALLOC_WIRED wire the allocated page 2072 * VM_ALLOC_ZERO prefer a zeroed page 2073 * 2074 * This routine may not sleep. 2075 */ 2076 vm_page_t 2077 vm_page_alloc_freelist(int flind, int req) 2078 { 2079 struct vnode *drop; 2080 vm_page_t m; 2081 u_int flags; 2082 int req_class; 2083 2084 req_class = req & VM_ALLOC_CLASS_MASK; 2085 2086 /* 2087 * The page daemon is allowed to dig deeper into the free page list. 2088 */ 2089 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 2090 req_class = VM_ALLOC_SYSTEM; 2091 2092 /* 2093 * Do not allocate reserved pages unless the req has asked for it. 2094 */ 2095 mtx_lock_flags(&vm_page_queue_free_mtx, MTX_RECURSE); 2096 if (vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_free_reserved || 2097 (req_class == VM_ALLOC_SYSTEM && 2098 vm_cnt.v_free_count + vm_cnt.v_cache_count > vm_cnt.v_interrupt_free_min) || 2099 (req_class == VM_ALLOC_INTERRUPT && 2100 vm_cnt.v_free_count + vm_cnt.v_cache_count > 0)) 2101 m = vm_phys_alloc_freelist_pages(flind, VM_FREEPOOL_DIRECT, 0); 2102 else { 2103 mtx_unlock(&vm_page_queue_free_mtx); 2104 atomic_add_int(&vm_pageout_deficit, 2105 max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1)); 2106 pagedaemon_wakeup(); 2107 return (NULL); 2108 } 2109 if (m == NULL) { 2110 mtx_unlock(&vm_page_queue_free_mtx); 2111 return (NULL); 2112 } 2113 drop = vm_page_alloc_init(m); 2114 mtx_unlock(&vm_page_queue_free_mtx); 2115 2116 /* 2117 * Initialize the page. Only the PG_ZERO flag is inherited. 2118 */ 2119 m->aflags = 0; 2120 flags = 0; 2121 if ((req & VM_ALLOC_ZERO) != 0) 2122 flags = PG_ZERO; 2123 m->flags &= flags; 2124 if ((req & VM_ALLOC_WIRED) != 0) { 2125 /* 2126 * The page lock is not required for wiring a page that does 2127 * not belong to an object. 2128 */ 2129 atomic_add_int(&vm_cnt.v_wire_count, 1); 2130 m->wire_count = 1; 2131 } 2132 /* Unmanaged pages don't use "act_count". */ 2133 m->oflags = VPO_UNMANAGED; 2134 if (drop != NULL) 2135 vdrop(drop); 2136 if (vm_paging_needed()) 2137 pagedaemon_wakeup(); 2138 return (m); 2139 } 2140 2141 #define VPSC_ANY 0 /* No restrictions. */ 2142 #define VPSC_NORESERV 1 /* Skip reservations; implies VPSC_NOSUPER. */ 2143 #define VPSC_NOSUPER 2 /* Skip superpages. */ 2144 2145 /* 2146 * vm_page_scan_contig: 2147 * 2148 * Scan vm_page_array[] between the specified entries "m_start" and 2149 * "m_end" for a run of contiguous physical pages that satisfy the 2150 * specified conditions, and return the lowest page in the run. The 2151 * specified "alignment" determines the alignment of the lowest physical 2152 * page in the run. If the specified "boundary" is non-zero, then the 2153 * run of physical pages cannot span a physical address that is a 2154 * multiple of "boundary". 2155 * 2156 * "m_end" is never dereferenced, so it need not point to a vm_page 2157 * structure within vm_page_array[]. 2158 * 2159 * "npages" must be greater than zero. "m_start" and "m_end" must not 2160 * span a hole (or discontiguity) in the physical address space. Both 2161 * "alignment" and "boundary" must be a power of two. 2162 */ 2163 vm_page_t 2164 vm_page_scan_contig(u_long npages, vm_page_t m_start, vm_page_t m_end, 2165 u_long alignment, vm_paddr_t boundary, int options) 2166 { 2167 struct mtx *m_mtx, *new_mtx; 2168 vm_object_t object; 2169 vm_paddr_t pa; 2170 vm_page_t m, m_run; 2171 #if VM_NRESERVLEVEL > 0 2172 int level; 2173 #endif 2174 int m_inc, order, run_ext, run_len; 2175 2176 KASSERT(npages > 0, ("npages is 0")); 2177 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 2178 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 2179 m_run = NULL; 2180 run_len = 0; 2181 m_mtx = NULL; 2182 for (m = m_start; m < m_end && run_len < npages; m += m_inc) { 2183 KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0, 2184 ("page %p is PG_FICTITIOUS or PG_MARKER", m)); 2185 2186 /* 2187 * If the current page would be the start of a run, check its 2188 * physical address against the end, alignment, and boundary 2189 * conditions. If it doesn't satisfy these conditions, either 2190 * terminate the scan or advance to the next page that 2191 * satisfies the failed condition. 2192 */ 2193 if (run_len == 0) { 2194 KASSERT(m_run == NULL, ("m_run != NULL")); 2195 if (m + npages > m_end) 2196 break; 2197 pa = VM_PAGE_TO_PHYS(m); 2198 if ((pa & (alignment - 1)) != 0) { 2199 m_inc = atop(roundup2(pa, alignment) - pa); 2200 continue; 2201 } 2202 if (rounddown2(pa ^ (pa + ptoa(npages) - 1), 2203 boundary) != 0) { 2204 m_inc = atop(roundup2(pa, boundary) - pa); 2205 continue; 2206 } 2207 } else 2208 KASSERT(m_run != NULL, ("m_run == NULL")); 2209 2210 /* 2211 * Avoid releasing and reacquiring the same page lock. 2212 */ 2213 new_mtx = vm_page_lockptr(m); 2214 if (m_mtx != new_mtx) { 2215 if (m_mtx != NULL) 2216 mtx_unlock(m_mtx); 2217 m_mtx = new_mtx; 2218 mtx_lock(m_mtx); 2219 } 2220 m_inc = 1; 2221 retry: 2222 if (m->wire_count != 0 || m->hold_count != 0) 2223 run_ext = 0; 2224 #if VM_NRESERVLEVEL > 0 2225 else if ((level = vm_reserv_level(m)) >= 0 && 2226 (options & VPSC_NORESERV) != 0) { 2227 run_ext = 0; 2228 /* Advance to the end of the reservation. */ 2229 pa = VM_PAGE_TO_PHYS(m); 2230 m_inc = atop(roundup2(pa + 1, vm_reserv_size(level)) - 2231 pa); 2232 } 2233 #endif 2234 else if ((object = m->object) != NULL) { 2235 /* 2236 * The page is considered eligible for relocation if 2237 * and only if it could be laundered or reclaimed by 2238 * the page daemon. 2239 */ 2240 if (!VM_OBJECT_TRYRLOCK(object)) { 2241 mtx_unlock(m_mtx); 2242 VM_OBJECT_RLOCK(object); 2243 mtx_lock(m_mtx); 2244 if (m->object != object) { 2245 /* 2246 * The page may have been freed. 2247 */ 2248 VM_OBJECT_RUNLOCK(object); 2249 goto retry; 2250 } else if (m->wire_count != 0 || 2251 m->hold_count != 0) { 2252 run_ext = 0; 2253 goto unlock; 2254 } 2255 } 2256 KASSERT((m->flags & PG_UNHOLDFREE) == 0, 2257 ("page %p is PG_UNHOLDFREE", m)); 2258 /* Don't care: PG_NODUMP, PG_WINATCFLS, PG_ZERO. */ 2259 if (object->type != OBJT_DEFAULT && 2260 object->type != OBJT_SWAP && 2261 object->type != OBJT_VNODE) 2262 run_ext = 0; 2263 else if ((m->flags & PG_CACHED) != 0 || 2264 m != vm_page_lookup(object, m->pindex)) { 2265 /* 2266 * The page is cached or recently converted 2267 * from cached to free. 2268 */ 2269 #if VM_NRESERVLEVEL > 0 2270 if (level >= 0) { 2271 /* 2272 * The page is reserved. Extend the 2273 * current run by one page. 2274 */ 2275 run_ext = 1; 2276 } else 2277 #endif 2278 if ((order = m->order) < VM_NFREEORDER) { 2279 /* 2280 * The page is enqueued in the 2281 * physical memory allocator's cache/ 2282 * free page queues. Moreover, it is 2283 * the first page in a power-of-two- 2284 * sized run of contiguous cache/free 2285 * pages. Add these pages to the end 2286 * of the current run, and jump 2287 * ahead. 2288 */ 2289 run_ext = 1 << order; 2290 m_inc = 1 << order; 2291 } else 2292 run_ext = 0; 2293 #if VM_NRESERVLEVEL > 0 2294 } else if ((options & VPSC_NOSUPER) != 0 && 2295 (level = vm_reserv_level_iffullpop(m)) >= 0) { 2296 run_ext = 0; 2297 /* Advance to the end of the superpage. */ 2298 pa = VM_PAGE_TO_PHYS(m); 2299 m_inc = atop(roundup2(pa + 1, 2300 vm_reserv_size(level)) - pa); 2301 #endif 2302 } else if (object->memattr == VM_MEMATTR_DEFAULT && 2303 m->queue != PQ_NONE && !vm_page_busied(m)) { 2304 /* 2305 * The page is allocated but eligible for 2306 * relocation. Extend the current run by one 2307 * page. 2308 */ 2309 KASSERT(pmap_page_get_memattr(m) == 2310 VM_MEMATTR_DEFAULT, 2311 ("page %p has an unexpected memattr", m)); 2312 KASSERT((m->oflags & (VPO_SWAPINPROG | 2313 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, 2314 ("page %p has unexpected oflags", m)); 2315 /* Don't care: VPO_NOSYNC. */ 2316 run_ext = 1; 2317 } else 2318 run_ext = 0; 2319 unlock: 2320 VM_OBJECT_RUNLOCK(object); 2321 #if VM_NRESERVLEVEL > 0 2322 } else if (level >= 0) { 2323 /* 2324 * The page is reserved but not yet allocated. In 2325 * other words, it is still cached or free. Extend 2326 * the current run by one page. 2327 */ 2328 run_ext = 1; 2329 #endif 2330 } else if ((order = m->order) < VM_NFREEORDER) { 2331 /* 2332 * The page is enqueued in the physical memory 2333 * allocator's cache/free page queues. Moreover, it 2334 * is the first page in a power-of-two-sized run of 2335 * contiguous cache/free pages. Add these pages to 2336 * the end of the current run, and jump ahead. 2337 */ 2338 run_ext = 1 << order; 2339 m_inc = 1 << order; 2340 } else { 2341 /* 2342 * Skip the page for one of the following reasons: (1) 2343 * It is enqueued in the physical memory allocator's 2344 * cache/free page queues. However, it is not the 2345 * first page in a run of contiguous cache/free pages. 2346 * (This case rarely occurs because the scan is 2347 * performed in ascending order.) (2) It is not 2348 * reserved, and it is transitioning from free to 2349 * allocated. (Conversely, the transition from 2350 * allocated to free for managed pages is blocked by 2351 * the page lock.) (3) It is allocated but not 2352 * contained by an object and not wired, e.g., 2353 * allocated by Xen's balloon driver. 2354 */ 2355 run_ext = 0; 2356 } 2357 2358 /* 2359 * Extend or reset the current run of pages. 2360 */ 2361 if (run_ext > 0) { 2362 if (run_len == 0) 2363 m_run = m; 2364 run_len += run_ext; 2365 } else { 2366 if (run_len > 0) { 2367 m_run = NULL; 2368 run_len = 0; 2369 } 2370 } 2371 } 2372 if (m_mtx != NULL) 2373 mtx_unlock(m_mtx); 2374 if (run_len >= npages) 2375 return (m_run); 2376 return (NULL); 2377 } 2378 2379 /* 2380 * vm_page_reclaim_run: 2381 * 2382 * Try to relocate each of the allocated virtual pages within the 2383 * specified run of physical pages to a new physical address. Free the 2384 * physical pages underlying the relocated virtual pages. A virtual page 2385 * is relocatable if and only if it could be laundered or reclaimed by 2386 * the page daemon. Whenever possible, a virtual page is relocated to a 2387 * physical address above "high". 2388 * 2389 * Returns 0 if every physical page within the run was already free or 2390 * just freed by a successful relocation. Otherwise, returns a non-zero 2391 * value indicating why the last attempt to relocate a virtual page was 2392 * unsuccessful. 2393 * 2394 * "req_class" must be an allocation class. 2395 */ 2396 static int 2397 vm_page_reclaim_run(int req_class, u_long npages, vm_page_t m_run, 2398 vm_paddr_t high) 2399 { 2400 struct mtx *m_mtx, *new_mtx; 2401 struct spglist free; 2402 vm_object_t object; 2403 vm_paddr_t pa; 2404 vm_page_t m, m_end, m_new; 2405 int error, order, req; 2406 2407 KASSERT((req_class & VM_ALLOC_CLASS_MASK) == req_class, 2408 ("req_class is not an allocation class")); 2409 SLIST_INIT(&free); 2410 error = 0; 2411 m = m_run; 2412 m_end = m_run + npages; 2413 m_mtx = NULL; 2414 for (; error == 0 && m < m_end; m++) { 2415 KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0, 2416 ("page %p is PG_FICTITIOUS or PG_MARKER", m)); 2417 2418 /* 2419 * Avoid releasing and reacquiring the same page lock. 2420 */ 2421 new_mtx = vm_page_lockptr(m); 2422 if (m_mtx != new_mtx) { 2423 if (m_mtx != NULL) 2424 mtx_unlock(m_mtx); 2425 m_mtx = new_mtx; 2426 mtx_lock(m_mtx); 2427 } 2428 retry: 2429 if (m->wire_count != 0 || m->hold_count != 0) 2430 error = EBUSY; 2431 else if ((object = m->object) != NULL) { 2432 /* 2433 * The page is relocated if and only if it could be 2434 * laundered or reclaimed by the page daemon. 2435 */ 2436 if (!VM_OBJECT_TRYWLOCK(object)) { 2437 mtx_unlock(m_mtx); 2438 VM_OBJECT_WLOCK(object); 2439 mtx_lock(m_mtx); 2440 if (m->object != object) { 2441 /* 2442 * The page may have been freed. 2443 */ 2444 VM_OBJECT_WUNLOCK(object); 2445 goto retry; 2446 } else if (m->wire_count != 0 || 2447 m->hold_count != 0) { 2448 error = EBUSY; 2449 goto unlock; 2450 } 2451 } 2452 KASSERT((m->flags & PG_UNHOLDFREE) == 0, 2453 ("page %p is PG_UNHOLDFREE", m)); 2454 /* Don't care: PG_NODUMP, PG_WINATCFLS, PG_ZERO. */ 2455 if (object->type != OBJT_DEFAULT && 2456 object->type != OBJT_SWAP && 2457 object->type != OBJT_VNODE) 2458 error = EINVAL; 2459 else if ((m->flags & PG_CACHED) != 0 || 2460 m != vm_page_lookup(object, m->pindex)) { 2461 /* 2462 * The page is cached or recently converted 2463 * from cached to free. 2464 */ 2465 VM_OBJECT_WUNLOCK(object); 2466 goto cached; 2467 } else if (object->memattr != VM_MEMATTR_DEFAULT) 2468 error = EINVAL; 2469 else if (m->queue != PQ_NONE && !vm_page_busied(m)) { 2470 KASSERT(pmap_page_get_memattr(m) == 2471 VM_MEMATTR_DEFAULT, 2472 ("page %p has an unexpected memattr", m)); 2473 KASSERT((m->oflags & (VPO_SWAPINPROG | 2474 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, 2475 ("page %p has unexpected oflags", m)); 2476 /* Don't care: VPO_NOSYNC. */ 2477 if (m->valid != 0) { 2478 /* 2479 * First, try to allocate a new page 2480 * that is above "high". Failing 2481 * that, try to allocate a new page 2482 * that is below "m_run". Allocate 2483 * the new page between the end of 2484 * "m_run" and "high" only as a last 2485 * resort. 2486 */ 2487 req = req_class | VM_ALLOC_NOOBJ; 2488 if ((m->flags & PG_NODUMP) != 0) 2489 req |= VM_ALLOC_NODUMP; 2490 if (trunc_page(high) != 2491 ~(vm_paddr_t)PAGE_MASK) { 2492 m_new = vm_page_alloc_contig( 2493 NULL, 0, req, 1, 2494 round_page(high), 2495 ~(vm_paddr_t)0, 2496 PAGE_SIZE, 0, 2497 VM_MEMATTR_DEFAULT); 2498 } else 2499 m_new = NULL; 2500 if (m_new == NULL) { 2501 pa = VM_PAGE_TO_PHYS(m_run); 2502 m_new = vm_page_alloc_contig( 2503 NULL, 0, req, 1, 2504 0, pa - 1, PAGE_SIZE, 0, 2505 VM_MEMATTR_DEFAULT); 2506 } 2507 if (m_new == NULL) { 2508 pa += ptoa(npages); 2509 m_new = vm_page_alloc_contig( 2510 NULL, 0, req, 1, 2511 pa, high, PAGE_SIZE, 0, 2512 VM_MEMATTR_DEFAULT); 2513 } 2514 if (m_new == NULL) { 2515 error = ENOMEM; 2516 goto unlock; 2517 } 2518 KASSERT(m_new->wire_count == 0, 2519 ("page %p is wired", m)); 2520 2521 /* 2522 * Replace "m" with the new page. For 2523 * vm_page_replace(), "m" must be busy 2524 * and dequeued. Finally, change "m" 2525 * as if vm_page_free() was called. 2526 */ 2527 if (object->ref_count != 0) 2528 pmap_remove_all(m); 2529 m_new->aflags = m->aflags; 2530 KASSERT(m_new->oflags == VPO_UNMANAGED, 2531 ("page %p is managed", m)); 2532 m_new->oflags = m->oflags & VPO_NOSYNC; 2533 pmap_copy_page(m, m_new); 2534 m_new->valid = m->valid; 2535 m_new->dirty = m->dirty; 2536 m->flags &= ~PG_ZERO; 2537 vm_page_xbusy(m); 2538 vm_page_remque(m); 2539 vm_page_replace_checked(m_new, object, 2540 m->pindex, m); 2541 m->valid = 0; 2542 vm_page_undirty(m); 2543 2544 /* 2545 * The new page must be deactivated 2546 * before the object is unlocked. 2547 */ 2548 new_mtx = vm_page_lockptr(m_new); 2549 if (m_mtx != new_mtx) { 2550 mtx_unlock(m_mtx); 2551 m_mtx = new_mtx; 2552 mtx_lock(m_mtx); 2553 } 2554 vm_page_deactivate(m_new); 2555 } else { 2556 m->flags &= ~PG_ZERO; 2557 vm_page_remque(m); 2558 vm_page_remove(m); 2559 KASSERT(m->dirty == 0, 2560 ("page %p is dirty", m)); 2561 } 2562 SLIST_INSERT_HEAD(&free, m, plinks.s.ss); 2563 } else 2564 error = EBUSY; 2565 unlock: 2566 VM_OBJECT_WUNLOCK(object); 2567 } else { 2568 cached: 2569 mtx_lock(&vm_page_queue_free_mtx); 2570 order = m->order; 2571 if (order < VM_NFREEORDER) { 2572 /* 2573 * The page is enqueued in the physical memory 2574 * allocator's cache/free page queues. 2575 * Moreover, it is the first page in a power- 2576 * of-two-sized run of contiguous cache/free 2577 * pages. Jump ahead to the last page within 2578 * that run, and continue from there. 2579 */ 2580 m += (1 << order) - 1; 2581 } 2582 #if VM_NRESERVLEVEL > 0 2583 else if (vm_reserv_is_page_free(m)) 2584 order = 0; 2585 #endif 2586 mtx_unlock(&vm_page_queue_free_mtx); 2587 if (order == VM_NFREEORDER) 2588 error = EINVAL; 2589 } 2590 } 2591 if (m_mtx != NULL) 2592 mtx_unlock(m_mtx); 2593 if ((m = SLIST_FIRST(&free)) != NULL) { 2594 mtx_lock(&vm_page_queue_free_mtx); 2595 do { 2596 SLIST_REMOVE_HEAD(&free, plinks.s.ss); 2597 vm_phys_freecnt_adj(m, 1); 2598 #if VM_NRESERVLEVEL > 0 2599 if (!vm_reserv_free_page(m)) 2600 #else 2601 if (true) 2602 #endif 2603 vm_phys_free_pages(m, 0); 2604 } while ((m = SLIST_FIRST(&free)) != NULL); 2605 vm_page_free_wakeup(); 2606 mtx_unlock(&vm_page_queue_free_mtx); 2607 } 2608 return (error); 2609 } 2610 2611 #define NRUNS 16 2612 2613 CTASSERT(powerof2(NRUNS)); 2614 2615 #define RUN_INDEX(count) ((count) & (NRUNS - 1)) 2616 2617 #define MIN_RECLAIM 8 2618 2619 /* 2620 * vm_page_reclaim_contig: 2621 * 2622 * Reclaim allocated, contiguous physical memory satisfying the specified 2623 * conditions by relocating the virtual pages using that physical memory. 2624 * Returns true if reclamation is successful and false otherwise. Since 2625 * relocation requires the allocation of physical pages, reclamation may 2626 * fail due to a shortage of cache/free pages. When reclamation fails, 2627 * callers are expected to perform VM_WAIT before retrying a failed 2628 * allocation operation, e.g., vm_page_alloc_contig(). 2629 * 2630 * The caller must always specify an allocation class through "req". 2631 * 2632 * allocation classes: 2633 * VM_ALLOC_NORMAL normal process request 2634 * VM_ALLOC_SYSTEM system *really* needs a page 2635 * VM_ALLOC_INTERRUPT interrupt time request 2636 * 2637 * The optional allocation flags are ignored. 2638 * 2639 * "npages" must be greater than zero. Both "alignment" and "boundary" 2640 * must be a power of two. 2641 */ 2642 bool 2643 vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low, vm_paddr_t high, 2644 u_long alignment, vm_paddr_t boundary) 2645 { 2646 vm_paddr_t curr_low; 2647 vm_page_t m_run, m_runs[NRUNS]; 2648 u_long count, reclaimed; 2649 int error, i, options, req_class; 2650 2651 KASSERT(npages > 0, ("npages is 0")); 2652 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 2653 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 2654 req_class = req & VM_ALLOC_CLASS_MASK; 2655 2656 /* 2657 * The page daemon is allowed to dig deeper into the free page list. 2658 */ 2659 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 2660 req_class = VM_ALLOC_SYSTEM; 2661 2662 /* 2663 * Return if the number of cached and free pages cannot satisfy the 2664 * requested allocation. 2665 */ 2666 count = vm_cnt.v_free_count + vm_cnt.v_cache_count; 2667 if (count < npages + vm_cnt.v_free_reserved || (count < npages + 2668 vm_cnt.v_interrupt_free_min && req_class == VM_ALLOC_SYSTEM) || 2669 (count < npages && req_class == VM_ALLOC_INTERRUPT)) 2670 return (false); 2671 2672 /* 2673 * Scan up to three times, relaxing the restrictions ("options") on 2674 * the reclamation of reservations and superpages each time. 2675 */ 2676 for (options = VPSC_NORESERV;;) { 2677 /* 2678 * Find the highest runs that satisfy the given constraints 2679 * and restrictions, and record them in "m_runs". 2680 */ 2681 curr_low = low; 2682 count = 0; 2683 for (;;) { 2684 m_run = vm_phys_scan_contig(npages, curr_low, high, 2685 alignment, boundary, options); 2686 if (m_run == NULL) 2687 break; 2688 curr_low = VM_PAGE_TO_PHYS(m_run) + ptoa(npages); 2689 m_runs[RUN_INDEX(count)] = m_run; 2690 count++; 2691 } 2692 2693 /* 2694 * Reclaim the highest runs in LIFO (descending) order until 2695 * the number of reclaimed pages, "reclaimed", is at least 2696 * MIN_RECLAIM. Reset "reclaimed" each time because each 2697 * reclamation is idempotent, and runs will (likely) recur 2698 * from one scan to the next as restrictions are relaxed. 2699 */ 2700 reclaimed = 0; 2701 for (i = 0; count > 0 && i < NRUNS; i++) { 2702 count--; 2703 m_run = m_runs[RUN_INDEX(count)]; 2704 error = vm_page_reclaim_run(req_class, npages, m_run, 2705 high); 2706 if (error == 0) { 2707 reclaimed += npages; 2708 if (reclaimed >= MIN_RECLAIM) 2709 return (true); 2710 } 2711 } 2712 2713 /* 2714 * Either relax the restrictions on the next scan or return if 2715 * the last scan had no restrictions. 2716 */ 2717 if (options == VPSC_NORESERV) 2718 options = VPSC_NOSUPER; 2719 else if (options == VPSC_NOSUPER) 2720 options = VPSC_ANY; 2721 else if (options == VPSC_ANY) 2722 return (reclaimed != 0); 2723 } 2724 } 2725 2726 /* 2727 * vm_wait: (also see VM_WAIT macro) 2728 * 2729 * Sleep until free pages are available for allocation. 2730 * - Called in various places before memory allocations. 2731 */ 2732 void 2733 vm_wait(void) 2734 { 2735 2736 mtx_lock(&vm_page_queue_free_mtx); 2737 if (curproc == pageproc) { 2738 vm_pageout_pages_needed = 1; 2739 msleep(&vm_pageout_pages_needed, &vm_page_queue_free_mtx, 2740 PDROP | PSWP, "VMWait", 0); 2741 } else { 2742 if (!vm_pageout_wanted) { 2743 vm_pageout_wanted = true; 2744 wakeup(&vm_pageout_wanted); 2745 } 2746 vm_pages_needed = true; 2747 msleep(&vm_cnt.v_free_count, &vm_page_queue_free_mtx, PDROP | PVM, 2748 "vmwait", 0); 2749 } 2750 } 2751 2752 /* 2753 * vm_waitpfault: (also see VM_WAITPFAULT macro) 2754 * 2755 * Sleep until free pages are available for allocation. 2756 * - Called only in vm_fault so that processes page faulting 2757 * can be easily tracked. 2758 * - Sleeps at a lower priority than vm_wait() so that vm_wait()ing 2759 * processes will be able to grab memory first. Do not change 2760 * this balance without careful testing first. 2761 */ 2762 void 2763 vm_waitpfault(void) 2764 { 2765 2766 mtx_lock(&vm_page_queue_free_mtx); 2767 if (!vm_pageout_wanted) { 2768 vm_pageout_wanted = true; 2769 wakeup(&vm_pageout_wanted); 2770 } 2771 vm_pages_needed = true; 2772 msleep(&vm_cnt.v_free_count, &vm_page_queue_free_mtx, PDROP | PUSER, 2773 "pfault", 0); 2774 } 2775 2776 struct vm_pagequeue * 2777 vm_page_pagequeue(vm_page_t m) 2778 { 2779 2780 return (&vm_phys_domain(m)->vmd_pagequeues[m->queue]); 2781 } 2782 2783 /* 2784 * vm_page_dequeue: 2785 * 2786 * Remove the given page from its current page queue. 2787 * 2788 * The page must be locked. 2789 */ 2790 void 2791 vm_page_dequeue(vm_page_t m) 2792 { 2793 struct vm_pagequeue *pq; 2794 2795 vm_page_assert_locked(m); 2796 KASSERT(m->queue < PQ_COUNT, ("vm_page_dequeue: page %p is not queued", 2797 m)); 2798 pq = vm_page_pagequeue(m); 2799 vm_pagequeue_lock(pq); 2800 m->queue = PQ_NONE; 2801 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2802 vm_pagequeue_cnt_dec(pq); 2803 vm_pagequeue_unlock(pq); 2804 } 2805 2806 /* 2807 * vm_page_dequeue_locked: 2808 * 2809 * Remove the given page from its current page queue. 2810 * 2811 * The page and page queue must be locked. 2812 */ 2813 void 2814 vm_page_dequeue_locked(vm_page_t m) 2815 { 2816 struct vm_pagequeue *pq; 2817 2818 vm_page_lock_assert(m, MA_OWNED); 2819 pq = vm_page_pagequeue(m); 2820 vm_pagequeue_assert_locked(pq); 2821 m->queue = PQ_NONE; 2822 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2823 vm_pagequeue_cnt_dec(pq); 2824 } 2825 2826 /* 2827 * vm_page_enqueue: 2828 * 2829 * Add the given page to the specified page queue. 2830 * 2831 * The page must be locked. 2832 */ 2833 static void 2834 vm_page_enqueue(uint8_t queue, vm_page_t m) 2835 { 2836 struct vm_pagequeue *pq; 2837 2838 vm_page_lock_assert(m, MA_OWNED); 2839 KASSERT(queue < PQ_COUNT, 2840 ("vm_page_enqueue: invalid queue %u request for page %p", 2841 queue, m)); 2842 pq = &vm_phys_domain(m)->vmd_pagequeues[queue]; 2843 vm_pagequeue_lock(pq); 2844 m->queue = queue; 2845 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 2846 vm_pagequeue_cnt_inc(pq); 2847 vm_pagequeue_unlock(pq); 2848 } 2849 2850 /* 2851 * vm_page_requeue: 2852 * 2853 * Move the given page to the tail of its current page queue. 2854 * 2855 * The page must be locked. 2856 */ 2857 void 2858 vm_page_requeue(vm_page_t m) 2859 { 2860 struct vm_pagequeue *pq; 2861 2862 vm_page_lock_assert(m, MA_OWNED); 2863 KASSERT(m->queue != PQ_NONE, 2864 ("vm_page_requeue: page %p is not queued", m)); 2865 pq = vm_page_pagequeue(m); 2866 vm_pagequeue_lock(pq); 2867 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2868 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 2869 vm_pagequeue_unlock(pq); 2870 } 2871 2872 /* 2873 * vm_page_requeue_locked: 2874 * 2875 * Move the given page to the tail of its current page queue. 2876 * 2877 * The page queue must be locked. 2878 */ 2879 void 2880 vm_page_requeue_locked(vm_page_t m) 2881 { 2882 struct vm_pagequeue *pq; 2883 2884 KASSERT(m->queue != PQ_NONE, 2885 ("vm_page_requeue_locked: page %p is not queued", m)); 2886 pq = vm_page_pagequeue(m); 2887 vm_pagequeue_assert_locked(pq); 2888 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 2889 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 2890 } 2891 2892 /* 2893 * vm_page_activate: 2894 * 2895 * Put the specified page on the active list (if appropriate). 2896 * Ensure that act_count is at least ACT_INIT but do not otherwise 2897 * mess with it. 2898 * 2899 * The page must be locked. 2900 */ 2901 void 2902 vm_page_activate(vm_page_t m) 2903 { 2904 int queue; 2905 2906 vm_page_lock_assert(m, MA_OWNED); 2907 if ((queue = m->queue) != PQ_ACTIVE) { 2908 if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) { 2909 if (m->act_count < ACT_INIT) 2910 m->act_count = ACT_INIT; 2911 if (queue != PQ_NONE) 2912 vm_page_dequeue(m); 2913 vm_page_enqueue(PQ_ACTIVE, m); 2914 } else 2915 KASSERT(queue == PQ_NONE, 2916 ("vm_page_activate: wired page %p is queued", m)); 2917 } else { 2918 if (m->act_count < ACT_INIT) 2919 m->act_count = ACT_INIT; 2920 } 2921 } 2922 2923 /* 2924 * vm_page_free_wakeup: 2925 * 2926 * Helper routine for vm_page_free_toq() and vm_page_cache(). This 2927 * routine is called when a page has been added to the cache or free 2928 * queues. 2929 * 2930 * The page queues must be locked. 2931 */ 2932 static inline void 2933 vm_page_free_wakeup(void) 2934 { 2935 2936 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 2937 /* 2938 * if pageout daemon needs pages, then tell it that there are 2939 * some free. 2940 */ 2941 if (vm_pageout_pages_needed && 2942 vm_cnt.v_cache_count + vm_cnt.v_free_count >= vm_cnt.v_pageout_free_min) { 2943 wakeup(&vm_pageout_pages_needed); 2944 vm_pageout_pages_needed = 0; 2945 } 2946 /* 2947 * wakeup processes that are waiting on memory if we hit a 2948 * high water mark. And wakeup scheduler process if we have 2949 * lots of memory. this process will swapin processes. 2950 */ 2951 if (vm_pages_needed && !vm_page_count_min()) { 2952 vm_pages_needed = false; 2953 wakeup(&vm_cnt.v_free_count); 2954 } 2955 } 2956 2957 /* 2958 * Turn a cached page into a free page, by changing its attributes. 2959 * Keep the statistics up-to-date. 2960 * 2961 * The free page queue must be locked. 2962 */ 2963 static void 2964 vm_page_cache_turn_free(vm_page_t m) 2965 { 2966 2967 mtx_assert(&vm_page_queue_free_mtx, MA_OWNED); 2968 2969 m->object = NULL; 2970 m->valid = 0; 2971 KASSERT((m->flags & PG_CACHED) != 0, 2972 ("vm_page_cache_turn_free: page %p is not cached", m)); 2973 m->flags &= ~PG_CACHED; 2974 vm_cnt.v_cache_count--; 2975 vm_phys_freecnt_adj(m, 1); 2976 } 2977 2978 /* 2979 * vm_page_free_toq: 2980 * 2981 * Returns the given page to the free list, 2982 * disassociating it with any VM object. 2983 * 2984 * The object must be locked. The page must be locked if it is managed. 2985 */ 2986 void 2987 vm_page_free_toq(vm_page_t m) 2988 { 2989 2990 if ((m->oflags & VPO_UNMANAGED) == 0) { 2991 vm_page_lock_assert(m, MA_OWNED); 2992 KASSERT(!pmap_page_is_mapped(m), 2993 ("vm_page_free_toq: freeing mapped page %p", m)); 2994 } else 2995 KASSERT(m->queue == PQ_NONE, 2996 ("vm_page_free_toq: unmanaged page %p is queued", m)); 2997 PCPU_INC(cnt.v_tfree); 2998 2999 if (vm_page_sbusied(m)) 3000 panic("vm_page_free: freeing busy page %p", m); 3001 3002 /* 3003 * Unqueue, then remove page. Note that we cannot destroy 3004 * the page here because we do not want to call the pager's 3005 * callback routine until after we've put the page on the 3006 * appropriate free queue. 3007 */ 3008 vm_page_remque(m); 3009 vm_page_remove(m); 3010 3011 /* 3012 * If fictitious remove object association and 3013 * return, otherwise delay object association removal. 3014 */ 3015 if ((m->flags & PG_FICTITIOUS) != 0) { 3016 return; 3017 } 3018 3019 m->valid = 0; 3020 vm_page_undirty(m); 3021 3022 if (m->wire_count != 0) 3023 panic("vm_page_free: freeing wired page %p", m); 3024 if (m->hold_count != 0) { 3025 m->flags &= ~PG_ZERO; 3026 KASSERT((m->flags & PG_UNHOLDFREE) == 0, 3027 ("vm_page_free: freeing PG_UNHOLDFREE page %p", m)); 3028 m->flags |= PG_UNHOLDFREE; 3029 } else { 3030 /* 3031 * Restore the default memory attribute to the page. 3032 */ 3033 if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT) 3034 pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT); 3035 3036 /* 3037 * Insert the page into the physical memory allocator's 3038 * cache/free page queues. 3039 */ 3040 mtx_lock(&vm_page_queue_free_mtx); 3041 vm_phys_freecnt_adj(m, 1); 3042 #if VM_NRESERVLEVEL > 0 3043 if (!vm_reserv_free_page(m)) 3044 #else 3045 if (TRUE) 3046 #endif 3047 vm_phys_free_pages(m, 0); 3048 vm_page_free_wakeup(); 3049 mtx_unlock(&vm_page_queue_free_mtx); 3050 } 3051 } 3052 3053 /* 3054 * vm_page_wire: 3055 * 3056 * Mark this page as wired down by yet 3057 * another map, removing it from paging queues 3058 * as necessary. 3059 * 3060 * If the page is fictitious, then its wire count must remain one. 3061 * 3062 * The page must be locked. 3063 */ 3064 void 3065 vm_page_wire(vm_page_t m) 3066 { 3067 3068 /* 3069 * Only bump the wire statistics if the page is not already wired, 3070 * and only unqueue the page if it is on some queue (if it is unmanaged 3071 * it is already off the queues). 3072 */ 3073 vm_page_lock_assert(m, MA_OWNED); 3074 if ((m->flags & PG_FICTITIOUS) != 0) { 3075 KASSERT(m->wire_count == 1, 3076 ("vm_page_wire: fictitious page %p's wire count isn't one", 3077 m)); 3078 return; 3079 } 3080 if (m->wire_count == 0) { 3081 KASSERT((m->oflags & VPO_UNMANAGED) == 0 || 3082 m->queue == PQ_NONE, 3083 ("vm_page_wire: unmanaged page %p is queued", m)); 3084 vm_page_remque(m); 3085 atomic_add_int(&vm_cnt.v_wire_count, 1); 3086 } 3087 m->wire_count++; 3088 KASSERT(m->wire_count != 0, ("vm_page_wire: wire_count overflow m=%p", m)); 3089 } 3090 3091 /* 3092 * vm_page_unwire: 3093 * 3094 * Release one wiring of the specified page, potentially allowing it to be 3095 * paged out. Returns TRUE if the number of wirings transitions to zero and 3096 * FALSE otherwise. 3097 * 3098 * Only managed pages belonging to an object can be paged out. If the number 3099 * of wirings transitions to zero and the page is eligible for page out, then 3100 * the page is added to the specified paging queue (unless PQ_NONE is 3101 * specified). 3102 * 3103 * If a page is fictitious, then its wire count must always be one. 3104 * 3105 * A managed page must be locked. 3106 */ 3107 boolean_t 3108 vm_page_unwire(vm_page_t m, uint8_t queue) 3109 { 3110 3111 KASSERT(queue < PQ_COUNT || queue == PQ_NONE, 3112 ("vm_page_unwire: invalid queue %u request for page %p", 3113 queue, m)); 3114 if ((m->oflags & VPO_UNMANAGED) == 0) 3115 vm_page_assert_locked(m); 3116 if ((m->flags & PG_FICTITIOUS) != 0) { 3117 KASSERT(m->wire_count == 1, 3118 ("vm_page_unwire: fictitious page %p's wire count isn't one", m)); 3119 return (FALSE); 3120 } 3121 if (m->wire_count > 0) { 3122 m->wire_count--; 3123 if (m->wire_count == 0) { 3124 atomic_subtract_int(&vm_cnt.v_wire_count, 1); 3125 if ((m->oflags & VPO_UNMANAGED) == 0 && 3126 m->object != NULL && queue != PQ_NONE) { 3127 if (queue == PQ_INACTIVE) 3128 m->flags &= ~PG_WINATCFLS; 3129 vm_page_enqueue(queue, m); 3130 } 3131 return (TRUE); 3132 } else 3133 return (FALSE); 3134 } else 3135 panic("vm_page_unwire: page %p's wire count is zero", m); 3136 } 3137 3138 /* 3139 * Move the specified page to the inactive queue. 3140 * 3141 * Many pages placed on the inactive queue should actually go 3142 * into the cache, but it is difficult to figure out which. What 3143 * we do instead, if the inactive target is well met, is to put 3144 * clean pages at the head of the inactive queue instead of the tail. 3145 * This will cause them to be moved to the cache more quickly and 3146 * if not actively re-referenced, reclaimed more quickly. If we just 3147 * stick these pages at the end of the inactive queue, heavy filesystem 3148 * meta-data accesses can cause an unnecessary paging load on memory bound 3149 * processes. This optimization causes one-time-use metadata to be 3150 * reused more quickly. 3151 * 3152 * Normally noreuse is FALSE, resulting in LRU operation. noreuse is set 3153 * to TRUE if we want this page to be 'as if it were placed in the cache', 3154 * except without unmapping it from the process address space. In 3155 * practice this is implemented by inserting the page at the head of the 3156 * queue, using a marker page to guide FIFO insertion ordering. 3157 * 3158 * The page must be locked. 3159 */ 3160 static inline void 3161 _vm_page_deactivate(vm_page_t m, boolean_t noreuse) 3162 { 3163 struct vm_pagequeue *pq; 3164 int queue; 3165 3166 vm_page_assert_locked(m); 3167 3168 /* 3169 * Ignore if the page is already inactive, unless it is unlikely to be 3170 * reactivated. 3171 */ 3172 if ((queue = m->queue) == PQ_INACTIVE && !noreuse) 3173 return; 3174 if (m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0) { 3175 pq = &vm_phys_domain(m)->vmd_pagequeues[PQ_INACTIVE]; 3176 /* Avoid multiple acquisitions of the inactive queue lock. */ 3177 if (queue == PQ_INACTIVE) { 3178 vm_pagequeue_lock(pq); 3179 vm_page_dequeue_locked(m); 3180 } else { 3181 if (queue != PQ_NONE) 3182 vm_page_dequeue(m); 3183 m->flags &= ~PG_WINATCFLS; 3184 vm_pagequeue_lock(pq); 3185 } 3186 m->queue = PQ_INACTIVE; 3187 if (noreuse) 3188 TAILQ_INSERT_BEFORE(&vm_phys_domain(m)->vmd_inacthead, 3189 m, plinks.q); 3190 else 3191 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 3192 vm_pagequeue_cnt_inc(pq); 3193 vm_pagequeue_unlock(pq); 3194 } 3195 } 3196 3197 /* 3198 * Move the specified page to the inactive queue. 3199 * 3200 * The page must be locked. 3201 */ 3202 void 3203 vm_page_deactivate(vm_page_t m) 3204 { 3205 3206 _vm_page_deactivate(m, FALSE); 3207 } 3208 3209 /* 3210 * Move the specified page to the inactive queue with the expectation 3211 * that it is unlikely to be reused. 3212 * 3213 * The page must be locked. 3214 */ 3215 void 3216 vm_page_deactivate_noreuse(vm_page_t m) 3217 { 3218 3219 _vm_page_deactivate(m, TRUE); 3220 } 3221 3222 /* 3223 * vm_page_try_to_cache: 3224 * 3225 * Returns 0 on failure, 1 on success 3226 */ 3227 int 3228 vm_page_try_to_cache(vm_page_t m) 3229 { 3230 3231 vm_page_lock_assert(m, MA_OWNED); 3232 VM_OBJECT_ASSERT_WLOCKED(m->object); 3233 if (m->dirty || m->hold_count || m->wire_count || 3234 (m->oflags & VPO_UNMANAGED) != 0 || vm_page_busied(m)) 3235 return (0); 3236 pmap_remove_all(m); 3237 if (m->dirty) 3238 return (0); 3239 vm_page_cache(m); 3240 return (1); 3241 } 3242 3243 /* 3244 * vm_page_try_to_free() 3245 * 3246 * Attempt to free the page. If we cannot free it, we do nothing. 3247 * 1 is returned on success, 0 on failure. 3248 */ 3249 int 3250 vm_page_try_to_free(vm_page_t m) 3251 { 3252 3253 vm_page_lock_assert(m, MA_OWNED); 3254 if (m->object != NULL) 3255 VM_OBJECT_ASSERT_WLOCKED(m->object); 3256 if (m->dirty || m->hold_count || m->wire_count || 3257 (m->oflags & VPO_UNMANAGED) != 0 || vm_page_busied(m)) 3258 return (0); 3259 pmap_remove_all(m); 3260 if (m->dirty) 3261 return (0); 3262 vm_page_free(m); 3263 return (1); 3264 } 3265 3266 /* 3267 * vm_page_cache 3268 * 3269 * Put the specified page onto the page cache queue (if appropriate). 3270 * 3271 * The object and page must be locked. 3272 */ 3273 void 3274 vm_page_cache(vm_page_t m) 3275 { 3276 vm_object_t object; 3277 boolean_t cache_was_empty; 3278 3279 vm_page_lock_assert(m, MA_OWNED); 3280 object = m->object; 3281 VM_OBJECT_ASSERT_WLOCKED(object); 3282 if (vm_page_busied(m) || (m->oflags & VPO_UNMANAGED) || 3283 m->hold_count || m->wire_count) 3284 panic("vm_page_cache: attempting to cache busy page"); 3285 KASSERT(!pmap_page_is_mapped(m), 3286 ("vm_page_cache: page %p is mapped", m)); 3287 KASSERT(m->dirty == 0, ("vm_page_cache: page %p is dirty", m)); 3288 if (m->valid == 0 || object->type == OBJT_DEFAULT || 3289 (object->type == OBJT_SWAP && 3290 !vm_pager_has_page(object, m->pindex, NULL, NULL))) { 3291 /* 3292 * Hypothesis: A cache-eligible page belonging to a 3293 * default object or swap object but without a backing 3294 * store must be zero filled. 3295 */ 3296 vm_page_free(m); 3297 return; 3298 } 3299 KASSERT((m->flags & PG_CACHED) == 0, 3300 ("vm_page_cache: page %p is already cached", m)); 3301 3302 /* 3303 * Remove the page from the paging queues. 3304 */ 3305 vm_page_remque(m); 3306 3307 /* 3308 * Remove the page from the object's collection of resident 3309 * pages. 3310 */ 3311 vm_radix_remove(&object->rtree, m->pindex); 3312 TAILQ_REMOVE(&object->memq, m, listq); 3313 object->resident_page_count--; 3314 3315 /* 3316 * Restore the default memory attribute to the page. 3317 */ 3318 if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT) 3319 pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT); 3320 3321 /* 3322 * Insert the page into the object's collection of cached pages 3323 * and the physical memory allocator's cache/free page queues. 3324 */ 3325 m->flags &= ~PG_ZERO; 3326 mtx_lock(&vm_page_queue_free_mtx); 3327 cache_was_empty = vm_radix_is_empty(&object->cache); 3328 if (vm_radix_insert(&object->cache, m)) { 3329 mtx_unlock(&vm_page_queue_free_mtx); 3330 if (object->type == OBJT_VNODE && 3331 object->resident_page_count == 0) 3332 vdrop(object->handle); 3333 m->object = NULL; 3334 vm_page_free(m); 3335 return; 3336 } 3337 3338 /* 3339 * The above call to vm_radix_insert() could reclaim the one pre- 3340 * existing cached page from this object, resulting in a call to 3341 * vdrop(). 3342 */ 3343 if (!cache_was_empty) 3344 cache_was_empty = vm_radix_is_singleton(&object->cache); 3345 3346 m->flags |= PG_CACHED; 3347 vm_cnt.v_cache_count++; 3348 PCPU_INC(cnt.v_tcached); 3349 #if VM_NRESERVLEVEL > 0 3350 if (!vm_reserv_free_page(m)) { 3351 #else 3352 if (TRUE) { 3353 #endif 3354 vm_phys_free_pages(m, 0); 3355 } 3356 vm_page_free_wakeup(); 3357 mtx_unlock(&vm_page_queue_free_mtx); 3358 3359 /* 3360 * Increment the vnode's hold count if this is the object's only 3361 * cached page. Decrement the vnode's hold count if this was 3362 * the object's only resident page. 3363 */ 3364 if (object->type == OBJT_VNODE) { 3365 if (cache_was_empty && object->resident_page_count != 0) 3366 vhold(object->handle); 3367 else if (!cache_was_empty && object->resident_page_count == 0) 3368 vdrop(object->handle); 3369 } 3370 } 3371 3372 /* 3373 * vm_page_advise 3374 * 3375 * Deactivate or do nothing, as appropriate. 3376 * 3377 * The object and page must be locked. 3378 */ 3379 void 3380 vm_page_advise(vm_page_t m, int advice) 3381 { 3382 3383 vm_page_assert_locked(m); 3384 VM_OBJECT_ASSERT_WLOCKED(m->object); 3385 if (advice == MADV_FREE) 3386 /* 3387 * Mark the page clean. This will allow the page to be freed 3388 * up by the system. However, such pages are often reused 3389 * quickly by malloc() so we do not do anything that would 3390 * cause a page fault if we can help it. 3391 * 3392 * Specifically, we do not try to actually free the page now 3393 * nor do we try to put it in the cache (which would cause a 3394 * page fault on reuse). 3395 * 3396 * But we do make the page as freeable as we can without 3397 * actually taking the step of unmapping it. 3398 */ 3399 vm_page_undirty(m); 3400 else if (advice != MADV_DONTNEED) 3401 return; 3402 3403 /* 3404 * Clear any references to the page. Otherwise, the page daemon will 3405 * immediately reactivate the page. 3406 */ 3407 vm_page_aflag_clear(m, PGA_REFERENCED); 3408 3409 if (advice != MADV_FREE && m->dirty == 0 && pmap_is_modified(m)) 3410 vm_page_dirty(m); 3411 3412 /* 3413 * Place clean pages near the head of the inactive queue rather than 3414 * the tail, thus defeating the queue's LRU operation and ensuring that 3415 * the page will be reused quickly. Dirty pages are given a chance to 3416 * cycle once through the inactive queue before becoming eligible for 3417 * laundering. 3418 */ 3419 _vm_page_deactivate(m, m->dirty == 0); 3420 } 3421 3422 /* 3423 * Grab a page, waiting until we are waken up due to the page 3424 * changing state. We keep on waiting, if the page continues 3425 * to be in the object. If the page doesn't exist, first allocate it 3426 * and then conditionally zero it. 3427 * 3428 * This routine may sleep. 3429 * 3430 * The object must be locked on entry. The lock will, however, be released 3431 * and reacquired if the routine sleeps. 3432 */ 3433 vm_page_t 3434 vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags) 3435 { 3436 vm_page_t m; 3437 int sleep; 3438 3439 VM_OBJECT_ASSERT_WLOCKED(object); 3440 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || 3441 (allocflags & VM_ALLOC_IGN_SBUSY) != 0, 3442 ("vm_page_grab: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch")); 3443 retrylookup: 3444 if ((m = vm_page_lookup(object, pindex)) != NULL) { 3445 sleep = (allocflags & VM_ALLOC_IGN_SBUSY) != 0 ? 3446 vm_page_xbusied(m) : vm_page_busied(m); 3447 if (sleep) { 3448 if ((allocflags & VM_ALLOC_NOWAIT) != 0) 3449 return (NULL); 3450 /* 3451 * Reference the page before unlocking and 3452 * sleeping so that the page daemon is less 3453 * likely to reclaim it. 3454 */ 3455 vm_page_aflag_set(m, PGA_REFERENCED); 3456 vm_page_lock(m); 3457 VM_OBJECT_WUNLOCK(object); 3458 vm_page_busy_sleep(m, "pgrbwt"); 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