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