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