1 /*- 2 * SPDX-License-Identifier: (BSD-3-Clause AND MIT-CMU) 3 * 4 * Copyright (c) 1991 Regents of the University of California. 5 * All rights reserved. 6 * Copyright (c) 1998 Matthew Dillon. All Rights Reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * The Mach Operating System project at Carnegie-Mellon University. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * from: @(#)vm_page.c 7.4 (Berkeley) 5/7/91 36 */ 37 38 /*- 39 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 40 * All rights reserved. 41 * 42 * Authors: Avadis Tevanian, Jr., Michael Wayne Young 43 * 44 * Permission to use, copy, modify and distribute this software and 45 * its documentation is hereby granted, provided that both the copyright 46 * notice and this permission notice appear in all copies of the 47 * software, derivative works or modified versions, and any portions 48 * thereof, and that both notices appear in supporting documentation. 49 * 50 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 51 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 52 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 53 * 54 * Carnegie Mellon requests users of this software to return to 55 * 56 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 57 * School of Computer Science 58 * Carnegie Mellon University 59 * Pittsburgh PA 15213-3890 60 * 61 * any improvements or extensions that they make and grant Carnegie the 62 * rights to redistribute these changes. 63 */ 64 65 /* 66 * GENERAL RULES ON VM_PAGE MANIPULATION 67 * 68 * - A page queue lock is required when adding or removing a page from a 69 * page queue regardless of other locks or the busy state of a page. 70 * 71 * * In general, no thread besides the page daemon can acquire or 72 * hold more than one page queue lock at a time. 73 * 74 * * The page daemon can acquire and hold any pair of page queue 75 * locks in any order. 76 * 77 * - The object lock is required when inserting or removing 78 * pages from an object (vm_page_insert() or vm_page_remove()). 79 * 80 */ 81 82 /* 83 * Resident memory management module. 84 */ 85 86 #include <sys/cdefs.h> 87 __FBSDID("$FreeBSD$"); 88 89 #include "opt_vm.h" 90 91 #include <sys/param.h> 92 #include <sys/systm.h> 93 #include <sys/lock.h> 94 #include <sys/domainset.h> 95 #include <sys/kernel.h> 96 #include <sys/limits.h> 97 #include <sys/linker.h> 98 #include <sys/malloc.h> 99 #include <sys/mman.h> 100 #include <sys/msgbuf.h> 101 #include <sys/mutex.h> 102 #include <sys/proc.h> 103 #include <sys/rwlock.h> 104 #include <sys/sbuf.h> 105 #include <sys/sched.h> 106 #include <sys/smp.h> 107 #include <sys/sysctl.h> 108 #include <sys/vmmeter.h> 109 #include <sys/vnode.h> 110 111 #include <vm/vm.h> 112 #include <vm/pmap.h> 113 #include <vm/vm_param.h> 114 #include <vm/vm_domainset.h> 115 #include <vm/vm_kern.h> 116 #include <vm/vm_map.h> 117 #include <vm/vm_object.h> 118 #include <vm/vm_page.h> 119 #include <vm/vm_pageout.h> 120 #include <vm/vm_phys.h> 121 #include <vm/vm_pagequeue.h> 122 #include <vm/vm_pager.h> 123 #include <vm/vm_radix.h> 124 #include <vm/vm_reserv.h> 125 #include <vm/vm_extern.h> 126 #include <vm/uma.h> 127 #include <vm/uma_int.h> 128 129 #include <machine/md_var.h> 130 131 extern int uma_startup_count(int); 132 extern void uma_startup(void *, int); 133 extern int vmem_startup_count(void); 134 135 struct vm_domain vm_dom[MAXMEMDOM]; 136 137 DPCPU_DEFINE_STATIC(struct vm_batchqueue, pqbatch[MAXMEMDOM][PQ_COUNT]); 138 139 struct mtx_padalign __exclusive_cache_line pa_lock[PA_LOCK_COUNT]; 140 141 struct mtx_padalign __exclusive_cache_line vm_domainset_lock; 142 /* The following fields are protected by the domainset lock. */ 143 domainset_t __exclusive_cache_line vm_min_domains; 144 domainset_t __exclusive_cache_line vm_severe_domains; 145 static int vm_min_waiters; 146 static int vm_severe_waiters; 147 static int vm_pageproc_waiters; 148 149 /* 150 * bogus page -- for I/O to/from partially complete buffers, 151 * or for paging into sparsely invalid regions. 152 */ 153 vm_page_t bogus_page; 154 155 vm_page_t vm_page_array; 156 long vm_page_array_size; 157 long first_page; 158 159 static int boot_pages; 160 SYSCTL_INT(_vm, OID_AUTO, boot_pages, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, 161 &boot_pages, 0, 162 "number of pages allocated for bootstrapping the VM system"); 163 164 static int pa_tryrelock_restart; 165 SYSCTL_INT(_vm, OID_AUTO, tryrelock_restart, CTLFLAG_RD, 166 &pa_tryrelock_restart, 0, "Number of tryrelock restarts"); 167 168 static TAILQ_HEAD(, vm_page) blacklist_head; 169 static int sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS); 170 SYSCTL_PROC(_vm, OID_AUTO, page_blacklist, CTLTYPE_STRING | CTLFLAG_RD | 171 CTLFLAG_MPSAFE, NULL, 0, sysctl_vm_page_blacklist, "A", "Blacklist pages"); 172 173 static uma_zone_t fakepg_zone; 174 175 static void vm_page_alloc_check(vm_page_t m); 176 static void vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits); 177 static void vm_page_dequeue_complete(vm_page_t m); 178 static void vm_page_enqueue(vm_page_t m, uint8_t queue); 179 static void vm_page_init(void *dummy); 180 static int vm_page_insert_after(vm_page_t m, vm_object_t object, 181 vm_pindex_t pindex, vm_page_t mpred); 182 static void vm_page_insert_radixdone(vm_page_t m, vm_object_t object, 183 vm_page_t mpred); 184 static int vm_page_reclaim_run(int req_class, int domain, u_long npages, 185 vm_page_t m_run, vm_paddr_t high); 186 static int vm_domain_alloc_fail(struct vm_domain *vmd, vm_object_t object, 187 int req); 188 static int vm_page_import(void *arg, void **store, int cnt, int domain, 189 int flags); 190 static void vm_page_release(void *arg, void **store, int cnt); 191 192 SYSINIT(vm_page, SI_SUB_VM, SI_ORDER_SECOND, vm_page_init, NULL); 193 194 static void 195 vm_page_init(void *dummy) 196 { 197 198 fakepg_zone = uma_zcreate("fakepg", sizeof(struct vm_page), NULL, NULL, 199 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE | UMA_ZONE_VM); 200 bogus_page = vm_page_alloc(NULL, 0, VM_ALLOC_NOOBJ | 201 VM_ALLOC_NORMAL | VM_ALLOC_WIRED); 202 } 203 204 /* 205 * The cache page zone is initialized later since we need to be able to allocate 206 * pages before UMA is fully initialized. 207 */ 208 static void 209 vm_page_init_cache_zones(void *dummy __unused) 210 { 211 struct vm_domain *vmd; 212 int i; 213 214 for (i = 0; i < vm_ndomains; i++) { 215 vmd = VM_DOMAIN(i); 216 /* 217 * Don't allow the page cache to take up more than .25% of 218 * memory. 219 */ 220 if (vmd->vmd_page_count / 400 < 256 * mp_ncpus) 221 continue; 222 vmd->vmd_pgcache = uma_zcache_create("vm pgcache", 223 sizeof(struct vm_page), NULL, NULL, NULL, NULL, 224 vm_page_import, vm_page_release, vmd, 225 UMA_ZONE_MAXBUCKET | UMA_ZONE_VM); 226 (void )uma_zone_set_maxcache(vmd->vmd_pgcache, 0); 227 } 228 } 229 SYSINIT(vm_page2, SI_SUB_VM_CONF, SI_ORDER_ANY, vm_page_init_cache_zones, NULL); 230 231 /* Make sure that u_long is at least 64 bits when PAGE_SIZE is 32K. */ 232 #if PAGE_SIZE == 32768 233 #ifdef CTASSERT 234 CTASSERT(sizeof(u_long) >= 8); 235 #endif 236 #endif 237 238 /* 239 * Try to acquire a physical address lock while a pmap is locked. If we 240 * fail to trylock we unlock and lock the pmap directly and cache the 241 * locked pa in *locked. The caller should then restart their loop in case 242 * the virtual to physical mapping has changed. 243 */ 244 int 245 vm_page_pa_tryrelock(pmap_t pmap, vm_paddr_t pa, vm_paddr_t *locked) 246 { 247 vm_paddr_t lockpa; 248 249 lockpa = *locked; 250 *locked = pa; 251 if (lockpa) { 252 PA_LOCK_ASSERT(lockpa, MA_OWNED); 253 if (PA_LOCKPTR(pa) == PA_LOCKPTR(lockpa)) 254 return (0); 255 PA_UNLOCK(lockpa); 256 } 257 if (PA_TRYLOCK(pa)) 258 return (0); 259 PMAP_UNLOCK(pmap); 260 atomic_add_int(&pa_tryrelock_restart, 1); 261 PA_LOCK(pa); 262 PMAP_LOCK(pmap); 263 return (EAGAIN); 264 } 265 266 /* 267 * vm_set_page_size: 268 * 269 * Sets the page size, perhaps based upon the memory 270 * size. Must be called before any use of page-size 271 * dependent functions. 272 */ 273 void 274 vm_set_page_size(void) 275 { 276 if (vm_cnt.v_page_size == 0) 277 vm_cnt.v_page_size = PAGE_SIZE; 278 if (((vm_cnt.v_page_size - 1) & vm_cnt.v_page_size) != 0) 279 panic("vm_set_page_size: page size not a power of two"); 280 } 281 282 /* 283 * vm_page_blacklist_next: 284 * 285 * Find the next entry in the provided string of blacklist 286 * addresses. Entries are separated by space, comma, or newline. 287 * If an invalid integer is encountered then the rest of the 288 * string is skipped. Updates the list pointer to the next 289 * character, or NULL if the string is exhausted or invalid. 290 */ 291 static vm_paddr_t 292 vm_page_blacklist_next(char **list, char *end) 293 { 294 vm_paddr_t bad; 295 char *cp, *pos; 296 297 if (list == NULL || *list == NULL) 298 return (0); 299 if (**list =='\0') { 300 *list = NULL; 301 return (0); 302 } 303 304 /* 305 * If there's no end pointer then the buffer is coming from 306 * the kenv and we know it's null-terminated. 307 */ 308 if (end == NULL) 309 end = *list + strlen(*list); 310 311 /* Ensure that strtoq() won't walk off the end */ 312 if (*end != '\0') { 313 if (*end == '\n' || *end == ' ' || *end == ',') 314 *end = '\0'; 315 else { 316 printf("Blacklist not terminated, skipping\n"); 317 *list = NULL; 318 return (0); 319 } 320 } 321 322 for (pos = *list; *pos != '\0'; pos = cp) { 323 bad = strtoq(pos, &cp, 0); 324 if (*cp == '\0' || *cp == ' ' || *cp == ',' || *cp == '\n') { 325 if (bad == 0) { 326 if (++cp < end) 327 continue; 328 else 329 break; 330 } 331 } else 332 break; 333 if (*cp == '\0' || ++cp >= end) 334 *list = NULL; 335 else 336 *list = cp; 337 return (trunc_page(bad)); 338 } 339 printf("Garbage in RAM blacklist, skipping\n"); 340 *list = NULL; 341 return (0); 342 } 343 344 bool 345 vm_page_blacklist_add(vm_paddr_t pa, bool verbose) 346 { 347 struct vm_domain *vmd; 348 vm_page_t m; 349 int ret; 350 351 m = vm_phys_paddr_to_vm_page(pa); 352 if (m == NULL) 353 return (true); /* page does not exist, no failure */ 354 355 vmd = vm_pagequeue_domain(m); 356 vm_domain_free_lock(vmd); 357 ret = vm_phys_unfree_page(m); 358 vm_domain_free_unlock(vmd); 359 if (ret != 0) { 360 vm_domain_freecnt_inc(vmd, -1); 361 TAILQ_INSERT_TAIL(&blacklist_head, m, listq); 362 if (verbose) 363 printf("Skipping page with pa 0x%jx\n", (uintmax_t)pa); 364 } 365 return (ret); 366 } 367 368 /* 369 * vm_page_blacklist_check: 370 * 371 * Iterate through the provided string of blacklist addresses, pulling 372 * each entry out of the physical allocator free list and putting it 373 * onto a list for reporting via the vm.page_blacklist sysctl. 374 */ 375 static void 376 vm_page_blacklist_check(char *list, char *end) 377 { 378 vm_paddr_t pa; 379 char *next; 380 381 next = list; 382 while (next != NULL) { 383 if ((pa = vm_page_blacklist_next(&next, end)) == 0) 384 continue; 385 vm_page_blacklist_add(pa, bootverbose); 386 } 387 } 388 389 /* 390 * vm_page_blacklist_load: 391 * 392 * Search for a special module named "ram_blacklist". It'll be a 393 * plain text file provided by the user via the loader directive 394 * of the same name. 395 */ 396 static void 397 vm_page_blacklist_load(char **list, char **end) 398 { 399 void *mod; 400 u_char *ptr; 401 u_int len; 402 403 mod = NULL; 404 ptr = NULL; 405 406 mod = preload_search_by_type("ram_blacklist"); 407 if (mod != NULL) { 408 ptr = preload_fetch_addr(mod); 409 len = preload_fetch_size(mod); 410 } 411 *list = ptr; 412 if (ptr != NULL) 413 *end = ptr + len; 414 else 415 *end = NULL; 416 return; 417 } 418 419 static int 420 sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS) 421 { 422 vm_page_t m; 423 struct sbuf sbuf; 424 int error, first; 425 426 first = 1; 427 error = sysctl_wire_old_buffer(req, 0); 428 if (error != 0) 429 return (error); 430 sbuf_new_for_sysctl(&sbuf, NULL, 128, req); 431 TAILQ_FOREACH(m, &blacklist_head, listq) { 432 sbuf_printf(&sbuf, "%s%#jx", first ? "" : ",", 433 (uintmax_t)m->phys_addr); 434 first = 0; 435 } 436 error = sbuf_finish(&sbuf); 437 sbuf_delete(&sbuf); 438 return (error); 439 } 440 441 /* 442 * Initialize a dummy page for use in scans of the specified paging queue. 443 * In principle, this function only needs to set the flag PG_MARKER. 444 * Nonetheless, it write busies and initializes the hold count to one as 445 * safety precautions. 446 */ 447 static void 448 vm_page_init_marker(vm_page_t marker, int queue, uint8_t aflags) 449 { 450 451 bzero(marker, sizeof(*marker)); 452 marker->flags = PG_MARKER; 453 marker->aflags = aflags; 454 marker->busy_lock = VPB_SINGLE_EXCLUSIVER; 455 marker->queue = queue; 456 marker->hold_count = 1; 457 } 458 459 static void 460 vm_page_domain_init(int domain) 461 { 462 struct vm_domain *vmd; 463 struct vm_pagequeue *pq; 464 int i; 465 466 vmd = VM_DOMAIN(domain); 467 bzero(vmd, sizeof(*vmd)); 468 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_INACTIVE].pq_name) = 469 "vm inactive pagequeue"; 470 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_ACTIVE].pq_name) = 471 "vm active pagequeue"; 472 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_LAUNDRY].pq_name) = 473 "vm laundry pagequeue"; 474 *__DECONST(char **, &vmd->vmd_pagequeues[PQ_UNSWAPPABLE].pq_name) = 475 "vm unswappable pagequeue"; 476 vmd->vmd_domain = domain; 477 vmd->vmd_page_count = 0; 478 vmd->vmd_free_count = 0; 479 vmd->vmd_segs = 0; 480 vmd->vmd_oom = FALSE; 481 for (i = 0; i < PQ_COUNT; i++) { 482 pq = &vmd->vmd_pagequeues[i]; 483 TAILQ_INIT(&pq->pq_pl); 484 mtx_init(&pq->pq_mutex, pq->pq_name, "vm pagequeue", 485 MTX_DEF | MTX_DUPOK); 486 pq->pq_pdpages = 0; 487 vm_page_init_marker(&vmd->vmd_markers[i], i, 0); 488 } 489 mtx_init(&vmd->vmd_free_mtx, "vm page free queue", NULL, MTX_DEF); 490 mtx_init(&vmd->vmd_pageout_mtx, "vm pageout lock", NULL, MTX_DEF); 491 snprintf(vmd->vmd_name, sizeof(vmd->vmd_name), "%d", domain); 492 493 /* 494 * inacthead is used to provide FIFO ordering for LRU-bypassing 495 * insertions. 496 */ 497 vm_page_init_marker(&vmd->vmd_inacthead, PQ_INACTIVE, PGA_ENQUEUED); 498 TAILQ_INSERT_HEAD(&vmd->vmd_pagequeues[PQ_INACTIVE].pq_pl, 499 &vmd->vmd_inacthead, plinks.q); 500 501 /* 502 * The clock pages are used to implement active queue scanning without 503 * requeues. Scans start at clock[0], which is advanced after the scan 504 * ends. When the two clock hands meet, they are reset and scanning 505 * resumes from the head of the queue. 506 */ 507 vm_page_init_marker(&vmd->vmd_clock[0], PQ_ACTIVE, PGA_ENQUEUED); 508 vm_page_init_marker(&vmd->vmd_clock[1], PQ_ACTIVE, PGA_ENQUEUED); 509 TAILQ_INSERT_HEAD(&vmd->vmd_pagequeues[PQ_ACTIVE].pq_pl, 510 &vmd->vmd_clock[0], plinks.q); 511 TAILQ_INSERT_TAIL(&vmd->vmd_pagequeues[PQ_ACTIVE].pq_pl, 512 &vmd->vmd_clock[1], plinks.q); 513 } 514 515 /* 516 * Initialize a physical page in preparation for adding it to the free 517 * lists. 518 */ 519 static void 520 vm_page_init_page(vm_page_t m, vm_paddr_t pa, int segind) 521 { 522 523 m->object = NULL; 524 m->wire_count = 0; 525 m->busy_lock = VPB_UNBUSIED; 526 m->hold_count = 0; 527 m->flags = m->aflags = 0; 528 m->phys_addr = pa; 529 m->queue = PQ_NONE; 530 m->psind = 0; 531 m->segind = segind; 532 m->order = VM_NFREEORDER; 533 m->pool = VM_FREEPOOL_DEFAULT; 534 m->valid = m->dirty = 0; 535 pmap_page_init(m); 536 } 537 538 /* 539 * vm_page_startup: 540 * 541 * Initializes the resident memory module. Allocates physical memory for 542 * bootstrapping UMA and some data structures that are used to manage 543 * physical pages. Initializes these structures, and populates the free 544 * page queues. 545 */ 546 vm_offset_t 547 vm_page_startup(vm_offset_t vaddr) 548 { 549 struct vm_phys_seg *seg; 550 vm_page_t m; 551 char *list, *listend; 552 vm_offset_t mapped; 553 vm_paddr_t end, high_avail, low_avail, new_end, page_range, size; 554 vm_paddr_t biggestsize, last_pa, pa; 555 u_long pagecount; 556 int biggestone, i, segind; 557 #ifdef WITNESS 558 int witness_size; 559 #endif 560 #if defined(__i386__) && defined(VM_PHYSSEG_DENSE) 561 long ii; 562 #endif 563 564 biggestsize = 0; 565 biggestone = 0; 566 vaddr = round_page(vaddr); 567 568 for (i = 0; phys_avail[i + 1]; i += 2) { 569 phys_avail[i] = round_page(phys_avail[i]); 570 phys_avail[i + 1] = trunc_page(phys_avail[i + 1]); 571 } 572 for (i = 0; phys_avail[i + 1]; i += 2) { 573 size = phys_avail[i + 1] - phys_avail[i]; 574 if (size > biggestsize) { 575 biggestone = i; 576 biggestsize = size; 577 } 578 } 579 580 end = phys_avail[biggestone+1]; 581 582 /* 583 * Initialize the page and queue locks. 584 */ 585 mtx_init(&vm_domainset_lock, "vm domainset lock", NULL, MTX_DEF); 586 for (i = 0; i < PA_LOCK_COUNT; i++) 587 mtx_init(&pa_lock[i], "vm page", NULL, MTX_DEF); 588 for (i = 0; i < vm_ndomains; i++) 589 vm_page_domain_init(i); 590 591 /* 592 * Allocate memory for use when boot strapping the kernel memory 593 * allocator. Tell UMA how many zones we are going to create 594 * before going fully functional. UMA will add its zones. 595 * 596 * VM startup zones: vmem, vmem_btag, VM OBJECT, RADIX NODE, MAP, 597 * KMAP ENTRY, MAP ENTRY, VMSPACE. 598 */ 599 boot_pages = uma_startup_count(8); 600 601 #ifndef UMA_MD_SMALL_ALLOC 602 /* vmem_startup() calls uma_prealloc(). */ 603 boot_pages += vmem_startup_count(); 604 /* vm_map_startup() calls uma_prealloc(). */ 605 boot_pages += howmany(MAX_KMAP, 606 UMA_SLAB_SPACE / sizeof(struct vm_map)); 607 608 /* 609 * Before going fully functional kmem_init() does allocation 610 * from "KMAP ENTRY" and vmem_create() does allocation from "vmem". 611 */ 612 boot_pages += 2; 613 #endif 614 /* 615 * CTFLAG_RDTUN doesn't work during the early boot process, so we must 616 * manually fetch the value. 617 */ 618 TUNABLE_INT_FETCH("vm.boot_pages", &boot_pages); 619 new_end = end - (boot_pages * UMA_SLAB_SIZE); 620 new_end = trunc_page(new_end); 621 mapped = pmap_map(&vaddr, new_end, end, 622 VM_PROT_READ | VM_PROT_WRITE); 623 bzero((void *)mapped, end - new_end); 624 uma_startup((void *)mapped, boot_pages); 625 626 #ifdef WITNESS 627 witness_size = round_page(witness_startup_count()); 628 new_end -= witness_size; 629 mapped = pmap_map(&vaddr, new_end, new_end + witness_size, 630 VM_PROT_READ | VM_PROT_WRITE); 631 bzero((void *)mapped, witness_size); 632 witness_startup((void *)mapped); 633 #endif 634 635 #if defined(__aarch64__) || defined(__amd64__) || defined(__arm__) || \ 636 defined(__i386__) || defined(__mips__) 637 /* 638 * Allocate a bitmap to indicate that a random physical page 639 * needs to be included in a minidump. 640 * 641 * The amd64 port needs this to indicate which direct map pages 642 * need to be dumped, via calls to dump_add_page()/dump_drop_page(). 643 * 644 * However, i386 still needs this workspace internally within the 645 * minidump code. In theory, they are not needed on i386, but are 646 * included should the sf_buf code decide to use them. 647 */ 648 last_pa = 0; 649 for (i = 0; dump_avail[i + 1] != 0; i += 2) 650 if (dump_avail[i + 1] > last_pa) 651 last_pa = dump_avail[i + 1]; 652 page_range = last_pa / PAGE_SIZE; 653 vm_page_dump_size = round_page(roundup2(page_range, NBBY) / NBBY); 654 new_end -= vm_page_dump_size; 655 vm_page_dump = (void *)(uintptr_t)pmap_map(&vaddr, new_end, 656 new_end + vm_page_dump_size, VM_PROT_READ | VM_PROT_WRITE); 657 bzero((void *)vm_page_dump, vm_page_dump_size); 658 #else 659 (void)last_pa; 660 #endif 661 #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) 662 /* 663 * Include the UMA bootstrap pages, witness pages and vm_page_dump 664 * in a crash dump. When pmap_map() uses the direct map, they are 665 * not automatically included. 666 */ 667 for (pa = new_end; pa < end; pa += PAGE_SIZE) 668 dump_add_page(pa); 669 #endif 670 phys_avail[biggestone + 1] = new_end; 671 #ifdef __amd64__ 672 /* 673 * Request that the physical pages underlying the message buffer be 674 * included in a crash dump. Since the message buffer is accessed 675 * through the direct map, they are not automatically included. 676 */ 677 pa = DMAP_TO_PHYS((vm_offset_t)msgbufp->msg_ptr); 678 last_pa = pa + round_page(msgbufsize); 679 while (pa < last_pa) { 680 dump_add_page(pa); 681 pa += PAGE_SIZE; 682 } 683 #endif 684 /* 685 * Compute the number of pages of memory that will be available for 686 * use, taking into account the overhead of a page structure per page. 687 * In other words, solve 688 * "available physical memory" - round_page(page_range * 689 * sizeof(struct vm_page)) = page_range * PAGE_SIZE 690 * for page_range. 691 */ 692 low_avail = phys_avail[0]; 693 high_avail = phys_avail[1]; 694 for (i = 0; i < vm_phys_nsegs; i++) { 695 if (vm_phys_segs[i].start < low_avail) 696 low_avail = vm_phys_segs[i].start; 697 if (vm_phys_segs[i].end > high_avail) 698 high_avail = vm_phys_segs[i].end; 699 } 700 /* Skip the first chunk. It is already accounted for. */ 701 for (i = 2; phys_avail[i + 1] != 0; i += 2) { 702 if (phys_avail[i] < low_avail) 703 low_avail = phys_avail[i]; 704 if (phys_avail[i + 1] > high_avail) 705 high_avail = phys_avail[i + 1]; 706 } 707 first_page = low_avail / PAGE_SIZE; 708 #ifdef VM_PHYSSEG_SPARSE 709 size = 0; 710 for (i = 0; i < vm_phys_nsegs; i++) 711 size += vm_phys_segs[i].end - vm_phys_segs[i].start; 712 for (i = 0; phys_avail[i + 1] != 0; i += 2) 713 size += phys_avail[i + 1] - phys_avail[i]; 714 #elif defined(VM_PHYSSEG_DENSE) 715 size = high_avail - low_avail; 716 #else 717 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." 718 #endif 719 720 #ifdef VM_PHYSSEG_DENSE 721 /* 722 * In the VM_PHYSSEG_DENSE case, the number of pages can account for 723 * the overhead of a page structure per page only if vm_page_array is 724 * allocated from the last physical memory chunk. Otherwise, we must 725 * allocate page structures representing the physical memory 726 * underlying vm_page_array, even though they will not be used. 727 */ 728 if (new_end != high_avail) 729 page_range = size / PAGE_SIZE; 730 else 731 #endif 732 { 733 page_range = size / (PAGE_SIZE + sizeof(struct vm_page)); 734 735 /* 736 * If the partial bytes remaining are large enough for 737 * a page (PAGE_SIZE) without a corresponding 738 * 'struct vm_page', then new_end will contain an 739 * extra page after subtracting the length of the VM 740 * page array. Compensate by subtracting an extra 741 * page from new_end. 742 */ 743 if (size % (PAGE_SIZE + sizeof(struct vm_page)) >= PAGE_SIZE) { 744 if (new_end == high_avail) 745 high_avail -= PAGE_SIZE; 746 new_end -= PAGE_SIZE; 747 } 748 } 749 end = new_end; 750 751 /* 752 * Reserve an unmapped guard page to trap access to vm_page_array[-1]. 753 * However, because this page is allocated from KVM, out-of-bounds 754 * accesses using the direct map will not be trapped. 755 */ 756 vaddr += PAGE_SIZE; 757 758 /* 759 * Allocate physical memory for the page structures, and map it. 760 */ 761 new_end = trunc_page(end - page_range * sizeof(struct vm_page)); 762 mapped = pmap_map(&vaddr, new_end, end, 763 VM_PROT_READ | VM_PROT_WRITE); 764 vm_page_array = (vm_page_t)mapped; 765 vm_page_array_size = page_range; 766 767 #if VM_NRESERVLEVEL > 0 768 /* 769 * Allocate physical memory for the reservation management system's 770 * data structures, and map it. 771 */ 772 if (high_avail == end) 773 high_avail = new_end; 774 new_end = vm_reserv_startup(&vaddr, new_end, high_avail); 775 #endif 776 #if defined(__aarch64__) || defined(__amd64__) || defined(__mips__) 777 /* 778 * Include vm_page_array and vm_reserv_array in a crash dump. 779 */ 780 for (pa = new_end; pa < end; pa += PAGE_SIZE) 781 dump_add_page(pa); 782 #endif 783 phys_avail[biggestone + 1] = new_end; 784 785 /* 786 * Add physical memory segments corresponding to the available 787 * physical pages. 788 */ 789 for (i = 0; phys_avail[i + 1] != 0; i += 2) 790 vm_phys_add_seg(phys_avail[i], phys_avail[i + 1]); 791 792 /* 793 * Initialize the physical memory allocator. 794 */ 795 vm_phys_init(); 796 797 /* 798 * Initialize the page structures and add every available page to the 799 * physical memory allocator's free lists. 800 */ 801 #if defined(__i386__) && defined(VM_PHYSSEG_DENSE) 802 for (ii = 0; ii < vm_page_array_size; ii++) { 803 m = &vm_page_array[ii]; 804 vm_page_init_page(m, (first_page + ii) << PAGE_SHIFT, 0); 805 m->flags = PG_FICTITIOUS; 806 } 807 #endif 808 vm_cnt.v_page_count = 0; 809 for (segind = 0; segind < vm_phys_nsegs; segind++) { 810 seg = &vm_phys_segs[segind]; 811 for (m = seg->first_page, pa = seg->start; pa < seg->end; 812 m++, pa += PAGE_SIZE) 813 vm_page_init_page(m, pa, segind); 814 815 /* 816 * Add the segment to the free lists only if it is covered by 817 * one of the ranges in phys_avail. Because we've added the 818 * ranges to the vm_phys_segs array, we can assume that each 819 * segment is either entirely contained in one of the ranges, 820 * or doesn't overlap any of them. 821 */ 822 for (i = 0; phys_avail[i + 1] != 0; i += 2) { 823 struct vm_domain *vmd; 824 825 if (seg->start < phys_avail[i] || 826 seg->end > phys_avail[i + 1]) 827 continue; 828 829 m = seg->first_page; 830 pagecount = (u_long)atop(seg->end - seg->start); 831 832 vmd = VM_DOMAIN(seg->domain); 833 vm_domain_free_lock(vmd); 834 vm_phys_free_contig(m, pagecount); 835 vm_domain_free_unlock(vmd); 836 vm_domain_freecnt_inc(vmd, pagecount); 837 vm_cnt.v_page_count += (u_int)pagecount; 838 839 vmd = VM_DOMAIN(seg->domain); 840 vmd->vmd_page_count += (u_int)pagecount; 841 vmd->vmd_segs |= 1UL << m->segind; 842 break; 843 } 844 } 845 846 /* 847 * Remove blacklisted pages from the physical memory allocator. 848 */ 849 TAILQ_INIT(&blacklist_head); 850 vm_page_blacklist_load(&list, &listend); 851 vm_page_blacklist_check(list, listend); 852 853 list = kern_getenv("vm.blacklist"); 854 vm_page_blacklist_check(list, NULL); 855 856 freeenv(list); 857 #if VM_NRESERVLEVEL > 0 858 /* 859 * Initialize the reservation management system. 860 */ 861 vm_reserv_init(); 862 #endif 863 864 return (vaddr); 865 } 866 867 void 868 vm_page_reference(vm_page_t m) 869 { 870 871 vm_page_aflag_set(m, PGA_REFERENCED); 872 } 873 874 /* 875 * vm_page_busy_downgrade: 876 * 877 * Downgrade an exclusive busy page into a single shared busy page. 878 */ 879 void 880 vm_page_busy_downgrade(vm_page_t m) 881 { 882 u_int x; 883 bool locked; 884 885 vm_page_assert_xbusied(m); 886 locked = mtx_owned(vm_page_lockptr(m)); 887 888 for (;;) { 889 x = m->busy_lock; 890 x &= VPB_BIT_WAITERS; 891 if (x != 0 && !locked) 892 vm_page_lock(m); 893 if (atomic_cmpset_rel_int(&m->busy_lock, 894 VPB_SINGLE_EXCLUSIVER | x, VPB_SHARERS_WORD(1))) 895 break; 896 if (x != 0 && !locked) 897 vm_page_unlock(m); 898 } 899 if (x != 0) { 900 wakeup(m); 901 if (!locked) 902 vm_page_unlock(m); 903 } 904 } 905 906 /* 907 * vm_page_sbusied: 908 * 909 * Return a positive value if the page is shared busied, 0 otherwise. 910 */ 911 int 912 vm_page_sbusied(vm_page_t m) 913 { 914 u_int x; 915 916 x = m->busy_lock; 917 return ((x & VPB_BIT_SHARED) != 0 && x != VPB_UNBUSIED); 918 } 919 920 /* 921 * vm_page_sunbusy: 922 * 923 * Shared unbusy a page. 924 */ 925 void 926 vm_page_sunbusy(vm_page_t m) 927 { 928 u_int x; 929 930 vm_page_lock_assert(m, MA_NOTOWNED); 931 vm_page_assert_sbusied(m); 932 933 for (;;) { 934 x = m->busy_lock; 935 if (VPB_SHARERS(x) > 1) { 936 if (atomic_cmpset_int(&m->busy_lock, x, 937 x - VPB_ONE_SHARER)) 938 break; 939 continue; 940 } 941 if ((x & VPB_BIT_WAITERS) == 0) { 942 KASSERT(x == VPB_SHARERS_WORD(1), 943 ("vm_page_sunbusy: invalid lock state")); 944 if (atomic_cmpset_int(&m->busy_lock, 945 VPB_SHARERS_WORD(1), VPB_UNBUSIED)) 946 break; 947 continue; 948 } 949 KASSERT(x == (VPB_SHARERS_WORD(1) | VPB_BIT_WAITERS), 950 ("vm_page_sunbusy: invalid lock state for waiters")); 951 952 vm_page_lock(m); 953 if (!atomic_cmpset_int(&m->busy_lock, x, VPB_UNBUSIED)) { 954 vm_page_unlock(m); 955 continue; 956 } 957 wakeup(m); 958 vm_page_unlock(m); 959 break; 960 } 961 } 962 963 /* 964 * vm_page_busy_sleep: 965 * 966 * Sleep and release the page lock, using the page pointer as wchan. 967 * This is used to implement the hard-path of busying mechanism. 968 * 969 * The given page must be locked. 970 * 971 * If nonshared is true, sleep only if the page is xbusy. 972 */ 973 void 974 vm_page_busy_sleep(vm_page_t m, const char *wmesg, bool nonshared) 975 { 976 u_int x; 977 978 vm_page_assert_locked(m); 979 980 x = m->busy_lock; 981 if (x == VPB_UNBUSIED || (nonshared && (x & VPB_BIT_SHARED) != 0) || 982 ((x & VPB_BIT_WAITERS) == 0 && 983 !atomic_cmpset_int(&m->busy_lock, x, x | VPB_BIT_WAITERS))) { 984 vm_page_unlock(m); 985 return; 986 } 987 msleep(m, vm_page_lockptr(m), PVM | PDROP, wmesg, 0); 988 } 989 990 /* 991 * vm_page_trysbusy: 992 * 993 * Try to shared busy a page. 994 * If the operation succeeds 1 is returned otherwise 0. 995 * The operation never sleeps. 996 */ 997 int 998 vm_page_trysbusy(vm_page_t m) 999 { 1000 u_int x; 1001 1002 for (;;) { 1003 x = m->busy_lock; 1004 if ((x & VPB_BIT_SHARED) == 0) 1005 return (0); 1006 if (atomic_cmpset_acq_int(&m->busy_lock, x, x + VPB_ONE_SHARER)) 1007 return (1); 1008 } 1009 } 1010 1011 static void 1012 vm_page_xunbusy_locked(vm_page_t m) 1013 { 1014 1015 vm_page_assert_xbusied(m); 1016 vm_page_assert_locked(m); 1017 1018 atomic_store_rel_int(&m->busy_lock, VPB_UNBUSIED); 1019 /* There is a waiter, do wakeup() instead of vm_page_flash(). */ 1020 wakeup(m); 1021 } 1022 1023 void 1024 vm_page_xunbusy_maybelocked(vm_page_t m) 1025 { 1026 bool lockacq; 1027 1028 vm_page_assert_xbusied(m); 1029 1030 /* 1031 * Fast path for unbusy. If it succeeds, we know that there 1032 * are no waiters, so we do not need a wakeup. 1033 */ 1034 if (atomic_cmpset_rel_int(&m->busy_lock, VPB_SINGLE_EXCLUSIVER, 1035 VPB_UNBUSIED)) 1036 return; 1037 1038 lockacq = !mtx_owned(vm_page_lockptr(m)); 1039 if (lockacq) 1040 vm_page_lock(m); 1041 vm_page_xunbusy_locked(m); 1042 if (lockacq) 1043 vm_page_unlock(m); 1044 } 1045 1046 /* 1047 * vm_page_xunbusy_hard: 1048 * 1049 * Called after the first try the exclusive unbusy of a page failed. 1050 * It is assumed that the waiters bit is on. 1051 */ 1052 void 1053 vm_page_xunbusy_hard(vm_page_t m) 1054 { 1055 1056 vm_page_assert_xbusied(m); 1057 1058 vm_page_lock(m); 1059 vm_page_xunbusy_locked(m); 1060 vm_page_unlock(m); 1061 } 1062 1063 /* 1064 * vm_page_flash: 1065 * 1066 * Wakeup anyone waiting for the page. 1067 * The ownership bits do not change. 1068 * 1069 * The given page must be locked. 1070 */ 1071 void 1072 vm_page_flash(vm_page_t m) 1073 { 1074 u_int x; 1075 1076 vm_page_lock_assert(m, MA_OWNED); 1077 1078 for (;;) { 1079 x = m->busy_lock; 1080 if ((x & VPB_BIT_WAITERS) == 0) 1081 return; 1082 if (atomic_cmpset_int(&m->busy_lock, x, 1083 x & (~VPB_BIT_WAITERS))) 1084 break; 1085 } 1086 wakeup(m); 1087 } 1088 1089 /* 1090 * Avoid releasing and reacquiring the same page lock. 1091 */ 1092 void 1093 vm_page_change_lock(vm_page_t m, struct mtx **mtx) 1094 { 1095 struct mtx *mtx1; 1096 1097 mtx1 = vm_page_lockptr(m); 1098 if (*mtx == mtx1) 1099 return; 1100 if (*mtx != NULL) 1101 mtx_unlock(*mtx); 1102 *mtx = mtx1; 1103 mtx_lock(mtx1); 1104 } 1105 1106 /* 1107 * Keep page from being freed by the page daemon 1108 * much of the same effect as wiring, except much lower 1109 * overhead and should be used only for *very* temporary 1110 * holding ("wiring"). 1111 */ 1112 void 1113 vm_page_hold(vm_page_t mem) 1114 { 1115 1116 vm_page_lock_assert(mem, MA_OWNED); 1117 mem->hold_count++; 1118 } 1119 1120 void 1121 vm_page_unhold(vm_page_t mem) 1122 { 1123 1124 vm_page_lock_assert(mem, MA_OWNED); 1125 KASSERT(mem->hold_count >= 1, ("vm_page_unhold: hold count < 0!!!")); 1126 --mem->hold_count; 1127 if (mem->hold_count == 0 && (mem->flags & PG_UNHOLDFREE) != 0) 1128 vm_page_free_toq(mem); 1129 } 1130 1131 /* 1132 * vm_page_unhold_pages: 1133 * 1134 * Unhold each of the pages that is referenced by the given array. 1135 */ 1136 void 1137 vm_page_unhold_pages(vm_page_t *ma, int count) 1138 { 1139 struct mtx *mtx; 1140 1141 mtx = NULL; 1142 for (; count != 0; count--) { 1143 vm_page_change_lock(*ma, &mtx); 1144 vm_page_unhold(*ma); 1145 ma++; 1146 } 1147 if (mtx != NULL) 1148 mtx_unlock(mtx); 1149 } 1150 1151 vm_page_t 1152 PHYS_TO_VM_PAGE(vm_paddr_t pa) 1153 { 1154 vm_page_t m; 1155 1156 #ifdef VM_PHYSSEG_SPARSE 1157 m = vm_phys_paddr_to_vm_page(pa); 1158 if (m == NULL) 1159 m = vm_phys_fictitious_to_vm_page(pa); 1160 return (m); 1161 #elif defined(VM_PHYSSEG_DENSE) 1162 long pi; 1163 1164 pi = atop(pa); 1165 if (pi >= first_page && (pi - first_page) < vm_page_array_size) { 1166 m = &vm_page_array[pi - first_page]; 1167 return (m); 1168 } 1169 return (vm_phys_fictitious_to_vm_page(pa)); 1170 #else 1171 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." 1172 #endif 1173 } 1174 1175 /* 1176 * vm_page_getfake: 1177 * 1178 * Create a fictitious page with the specified physical address and 1179 * memory attribute. The memory attribute is the only the machine- 1180 * dependent aspect of a fictitious page that must be initialized. 1181 */ 1182 vm_page_t 1183 vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr) 1184 { 1185 vm_page_t m; 1186 1187 m = uma_zalloc(fakepg_zone, M_WAITOK | M_ZERO); 1188 vm_page_initfake(m, paddr, memattr); 1189 return (m); 1190 } 1191 1192 void 1193 vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) 1194 { 1195 1196 if ((m->flags & PG_FICTITIOUS) != 0) { 1197 /* 1198 * The page's memattr might have changed since the 1199 * previous initialization. Update the pmap to the 1200 * new memattr. 1201 */ 1202 goto memattr; 1203 } 1204 m->phys_addr = paddr; 1205 m->queue = PQ_NONE; 1206 /* Fictitious pages don't use "segind". */ 1207 m->flags = PG_FICTITIOUS; 1208 /* Fictitious pages don't use "order" or "pool". */ 1209 m->oflags = VPO_UNMANAGED; 1210 m->busy_lock = VPB_SINGLE_EXCLUSIVER; 1211 m->wire_count = 1; 1212 pmap_page_init(m); 1213 memattr: 1214 pmap_page_set_memattr(m, memattr); 1215 } 1216 1217 /* 1218 * vm_page_putfake: 1219 * 1220 * Release a fictitious page. 1221 */ 1222 void 1223 vm_page_putfake(vm_page_t m) 1224 { 1225 1226 KASSERT((m->oflags & VPO_UNMANAGED) != 0, ("managed %p", m)); 1227 KASSERT((m->flags & PG_FICTITIOUS) != 0, 1228 ("vm_page_putfake: bad page %p", m)); 1229 uma_zfree(fakepg_zone, m); 1230 } 1231 1232 /* 1233 * vm_page_updatefake: 1234 * 1235 * Update the given fictitious page to the specified physical address and 1236 * memory attribute. 1237 */ 1238 void 1239 vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) 1240 { 1241 1242 KASSERT((m->flags & PG_FICTITIOUS) != 0, 1243 ("vm_page_updatefake: bad page %p", m)); 1244 m->phys_addr = paddr; 1245 pmap_page_set_memattr(m, memattr); 1246 } 1247 1248 /* 1249 * vm_page_free: 1250 * 1251 * Free a page. 1252 */ 1253 void 1254 vm_page_free(vm_page_t m) 1255 { 1256 1257 m->flags &= ~PG_ZERO; 1258 vm_page_free_toq(m); 1259 } 1260 1261 /* 1262 * vm_page_free_zero: 1263 * 1264 * Free a page to the zerod-pages queue 1265 */ 1266 void 1267 vm_page_free_zero(vm_page_t m) 1268 { 1269 1270 m->flags |= PG_ZERO; 1271 vm_page_free_toq(m); 1272 } 1273 1274 /* 1275 * Unbusy and handle the page queueing for a page from a getpages request that 1276 * was optionally read ahead or behind. 1277 */ 1278 void 1279 vm_page_readahead_finish(vm_page_t m) 1280 { 1281 1282 /* We shouldn't put invalid pages on queues. */ 1283 KASSERT(m->valid != 0, ("%s: %p is invalid", __func__, m)); 1284 1285 /* 1286 * Since the page is not the actually needed one, whether it should 1287 * be activated or deactivated is not obvious. Empirical results 1288 * have shown that deactivating the page is usually the best choice, 1289 * unless the page is wanted by another thread. 1290 */ 1291 vm_page_lock(m); 1292 if ((m->busy_lock & VPB_BIT_WAITERS) != 0) 1293 vm_page_activate(m); 1294 else 1295 vm_page_deactivate(m); 1296 vm_page_unlock(m); 1297 vm_page_xunbusy(m); 1298 } 1299 1300 /* 1301 * vm_page_sleep_if_busy: 1302 * 1303 * Sleep and release the page queues lock if the page is busied. 1304 * Returns TRUE if the thread slept. 1305 * 1306 * The given page must be unlocked and object containing it must 1307 * be locked. 1308 */ 1309 int 1310 vm_page_sleep_if_busy(vm_page_t m, const char *msg) 1311 { 1312 vm_object_t obj; 1313 1314 vm_page_lock_assert(m, MA_NOTOWNED); 1315 VM_OBJECT_ASSERT_WLOCKED(m->object); 1316 1317 if (vm_page_busied(m)) { 1318 /* 1319 * The page-specific object must be cached because page 1320 * identity can change during the sleep, causing the 1321 * re-lock of a different object. 1322 * It is assumed that a reference to the object is already 1323 * held by the callers. 1324 */ 1325 obj = m->object; 1326 vm_page_lock(m); 1327 VM_OBJECT_WUNLOCK(obj); 1328 vm_page_busy_sleep(m, msg, false); 1329 VM_OBJECT_WLOCK(obj); 1330 return (TRUE); 1331 } 1332 return (FALSE); 1333 } 1334 1335 /* 1336 * vm_page_dirty_KBI: [ internal use only ] 1337 * 1338 * Set all bits in the page's dirty field. 1339 * 1340 * The object containing the specified page must be locked if the 1341 * call is made from the machine-independent layer. 1342 * 1343 * See vm_page_clear_dirty_mask(). 1344 * 1345 * This function should only be called by vm_page_dirty(). 1346 */ 1347 void 1348 vm_page_dirty_KBI(vm_page_t m) 1349 { 1350 1351 /* Refer to this operation by its public name. */ 1352 KASSERT(m->valid == VM_PAGE_BITS_ALL, 1353 ("vm_page_dirty: page is invalid!")); 1354 m->dirty = VM_PAGE_BITS_ALL; 1355 } 1356 1357 /* 1358 * vm_page_insert: [ internal use only ] 1359 * 1360 * Inserts the given mem entry into the object and object list. 1361 * 1362 * The object must be locked. 1363 */ 1364 int 1365 vm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex) 1366 { 1367 vm_page_t mpred; 1368 1369 VM_OBJECT_ASSERT_WLOCKED(object); 1370 mpred = vm_radix_lookup_le(&object->rtree, pindex); 1371 return (vm_page_insert_after(m, object, pindex, mpred)); 1372 } 1373 1374 /* 1375 * vm_page_insert_after: 1376 * 1377 * Inserts the page "m" into the specified object at offset "pindex". 1378 * 1379 * The page "mpred" must immediately precede the offset "pindex" within 1380 * the specified object. 1381 * 1382 * The object must be locked. 1383 */ 1384 static int 1385 vm_page_insert_after(vm_page_t m, vm_object_t object, vm_pindex_t pindex, 1386 vm_page_t mpred) 1387 { 1388 vm_page_t msucc; 1389 1390 VM_OBJECT_ASSERT_WLOCKED(object); 1391 KASSERT(m->object == NULL, 1392 ("vm_page_insert_after: page already inserted")); 1393 if (mpred != NULL) { 1394 KASSERT(mpred->object == object, 1395 ("vm_page_insert_after: object doesn't contain mpred")); 1396 KASSERT(mpred->pindex < pindex, 1397 ("vm_page_insert_after: mpred doesn't precede pindex")); 1398 msucc = TAILQ_NEXT(mpred, listq); 1399 } else 1400 msucc = TAILQ_FIRST(&object->memq); 1401 if (msucc != NULL) 1402 KASSERT(msucc->pindex > pindex, 1403 ("vm_page_insert_after: msucc doesn't succeed pindex")); 1404 1405 /* 1406 * Record the object/offset pair in this page 1407 */ 1408 m->object = object; 1409 m->pindex = pindex; 1410 1411 /* 1412 * Now link into the object's ordered list of backed pages. 1413 */ 1414 if (vm_radix_insert(&object->rtree, m)) { 1415 m->object = NULL; 1416 m->pindex = 0; 1417 return (1); 1418 } 1419 vm_page_insert_radixdone(m, object, mpred); 1420 return (0); 1421 } 1422 1423 /* 1424 * vm_page_insert_radixdone: 1425 * 1426 * Complete page "m" insertion into the specified object after the 1427 * radix trie hooking. 1428 * 1429 * The page "mpred" must precede the offset "m->pindex" within the 1430 * specified object. 1431 * 1432 * The object must be locked. 1433 */ 1434 static void 1435 vm_page_insert_radixdone(vm_page_t m, vm_object_t object, vm_page_t mpred) 1436 { 1437 1438 VM_OBJECT_ASSERT_WLOCKED(object); 1439 KASSERT(object != NULL && m->object == object, 1440 ("vm_page_insert_radixdone: page %p has inconsistent object", m)); 1441 if (mpred != NULL) { 1442 KASSERT(mpred->object == object, 1443 ("vm_page_insert_after: object doesn't contain mpred")); 1444 KASSERT(mpred->pindex < m->pindex, 1445 ("vm_page_insert_after: mpred doesn't precede pindex")); 1446 } 1447 1448 if (mpred != NULL) 1449 TAILQ_INSERT_AFTER(&object->memq, mpred, m, listq); 1450 else 1451 TAILQ_INSERT_HEAD(&object->memq, m, listq); 1452 1453 /* 1454 * Show that the object has one more resident page. 1455 */ 1456 object->resident_page_count++; 1457 1458 /* 1459 * Hold the vnode until the last page is released. 1460 */ 1461 if (object->resident_page_count == 1 && object->type == OBJT_VNODE) 1462 vhold(object->handle); 1463 1464 /* 1465 * Since we are inserting a new and possibly dirty page, 1466 * update the object's OBJ_MIGHTBEDIRTY flag. 1467 */ 1468 if (pmap_page_is_write_mapped(m)) 1469 vm_object_set_writeable_dirty(object); 1470 } 1471 1472 /* 1473 * vm_page_remove: 1474 * 1475 * Removes the specified page from its containing object, but does not 1476 * invalidate any backing storage. 1477 * 1478 * The object must be locked. The page must be locked if it is managed. 1479 */ 1480 void 1481 vm_page_remove(vm_page_t m) 1482 { 1483 vm_object_t object; 1484 vm_page_t mrem; 1485 1486 if ((m->oflags & VPO_UNMANAGED) == 0) 1487 vm_page_assert_locked(m); 1488 if ((object = m->object) == NULL) 1489 return; 1490 VM_OBJECT_ASSERT_WLOCKED(object); 1491 if (vm_page_xbusied(m)) 1492 vm_page_xunbusy_maybelocked(m); 1493 mrem = vm_radix_remove(&object->rtree, m->pindex); 1494 KASSERT(mrem == m, ("removed page %p, expected page %p", mrem, m)); 1495 1496 /* 1497 * Now remove from the object's list of backed pages. 1498 */ 1499 TAILQ_REMOVE(&object->memq, m, listq); 1500 1501 /* 1502 * And show that the object has one fewer resident page. 1503 */ 1504 object->resident_page_count--; 1505 1506 /* 1507 * The vnode may now be recycled. 1508 */ 1509 if (object->resident_page_count == 0 && object->type == OBJT_VNODE) 1510 vdrop(object->handle); 1511 1512 m->object = NULL; 1513 } 1514 1515 /* 1516 * vm_page_lookup: 1517 * 1518 * Returns the page associated with the object/offset 1519 * pair specified; if none is found, NULL is returned. 1520 * 1521 * The object must be locked. 1522 */ 1523 vm_page_t 1524 vm_page_lookup(vm_object_t object, vm_pindex_t pindex) 1525 { 1526 1527 VM_OBJECT_ASSERT_LOCKED(object); 1528 return (vm_radix_lookup(&object->rtree, pindex)); 1529 } 1530 1531 /* 1532 * vm_page_find_least: 1533 * 1534 * Returns the page associated with the object with least pindex 1535 * greater than or equal to the parameter pindex, or NULL. 1536 * 1537 * The object must be locked. 1538 */ 1539 vm_page_t 1540 vm_page_find_least(vm_object_t object, vm_pindex_t pindex) 1541 { 1542 vm_page_t m; 1543 1544 VM_OBJECT_ASSERT_LOCKED(object); 1545 if ((m = TAILQ_FIRST(&object->memq)) != NULL && m->pindex < pindex) 1546 m = vm_radix_lookup_ge(&object->rtree, pindex); 1547 return (m); 1548 } 1549 1550 /* 1551 * Returns the given page's successor (by pindex) within the object if it is 1552 * resident; if none is found, NULL is returned. 1553 * 1554 * The object must be locked. 1555 */ 1556 vm_page_t 1557 vm_page_next(vm_page_t m) 1558 { 1559 vm_page_t next; 1560 1561 VM_OBJECT_ASSERT_LOCKED(m->object); 1562 if ((next = TAILQ_NEXT(m, listq)) != NULL) { 1563 MPASS(next->object == m->object); 1564 if (next->pindex != m->pindex + 1) 1565 next = NULL; 1566 } 1567 return (next); 1568 } 1569 1570 /* 1571 * Returns the given page's predecessor (by pindex) within the object if it is 1572 * resident; if none is found, NULL is returned. 1573 * 1574 * The object must be locked. 1575 */ 1576 vm_page_t 1577 vm_page_prev(vm_page_t m) 1578 { 1579 vm_page_t prev; 1580 1581 VM_OBJECT_ASSERT_LOCKED(m->object); 1582 if ((prev = TAILQ_PREV(m, pglist, listq)) != NULL) { 1583 MPASS(prev->object == m->object); 1584 if (prev->pindex != m->pindex - 1) 1585 prev = NULL; 1586 } 1587 return (prev); 1588 } 1589 1590 /* 1591 * Uses the page mnew as a replacement for an existing page at index 1592 * pindex which must be already present in the object. 1593 * 1594 * The existing page must not be on a paging queue. 1595 */ 1596 vm_page_t 1597 vm_page_replace(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex) 1598 { 1599 vm_page_t mold; 1600 1601 VM_OBJECT_ASSERT_WLOCKED(object); 1602 KASSERT(mnew->object == NULL, 1603 ("vm_page_replace: page %p already in object", mnew)); 1604 KASSERT(mnew->queue == PQ_NONE, 1605 ("vm_page_replace: new page %p is on a paging queue", mnew)); 1606 1607 /* 1608 * This function mostly follows vm_page_insert() and 1609 * vm_page_remove() without the radix, object count and vnode 1610 * dance. Double check such functions for more comments. 1611 */ 1612 1613 mnew->object = object; 1614 mnew->pindex = pindex; 1615 mold = vm_radix_replace(&object->rtree, mnew); 1616 KASSERT(mold->queue == PQ_NONE, 1617 ("vm_page_replace: old page %p is on a paging queue", mold)); 1618 1619 /* Keep the resident page list in sorted order. */ 1620 TAILQ_INSERT_AFTER(&object->memq, mold, mnew, listq); 1621 TAILQ_REMOVE(&object->memq, mold, listq); 1622 1623 mold->object = NULL; 1624 vm_page_xunbusy_maybelocked(mold); 1625 1626 /* 1627 * The object's resident_page_count does not change because we have 1628 * swapped one page for another, but OBJ_MIGHTBEDIRTY. 1629 */ 1630 if (pmap_page_is_write_mapped(mnew)) 1631 vm_object_set_writeable_dirty(object); 1632 return (mold); 1633 } 1634 1635 /* 1636 * vm_page_rename: 1637 * 1638 * Move the given memory entry from its 1639 * current object to the specified target object/offset. 1640 * 1641 * Note: swap associated with the page must be invalidated by the move. We 1642 * have to do this for several reasons: (1) we aren't freeing the 1643 * page, (2) we are dirtying the page, (3) the VM system is probably 1644 * moving the page from object A to B, and will then later move 1645 * the backing store from A to B and we can't have a conflict. 1646 * 1647 * Note: we *always* dirty the page. It is necessary both for the 1648 * fact that we moved it, and because we may be invalidating 1649 * swap. 1650 * 1651 * The objects must be locked. 1652 */ 1653 int 1654 vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex) 1655 { 1656 vm_page_t mpred; 1657 vm_pindex_t opidx; 1658 1659 VM_OBJECT_ASSERT_WLOCKED(new_object); 1660 1661 mpred = vm_radix_lookup_le(&new_object->rtree, new_pindex); 1662 KASSERT(mpred == NULL || mpred->pindex != new_pindex, 1663 ("vm_page_rename: pindex already renamed")); 1664 1665 /* 1666 * Create a custom version of vm_page_insert() which does not depend 1667 * by m_prev and can cheat on the implementation aspects of the 1668 * function. 1669 */ 1670 opidx = m->pindex; 1671 m->pindex = new_pindex; 1672 if (vm_radix_insert(&new_object->rtree, m)) { 1673 m->pindex = opidx; 1674 return (1); 1675 } 1676 1677 /* 1678 * The operation cannot fail anymore. The removal must happen before 1679 * the listq iterator is tainted. 1680 */ 1681 m->pindex = opidx; 1682 vm_page_lock(m); 1683 vm_page_remove(m); 1684 1685 /* Return back to the new pindex to complete vm_page_insert(). */ 1686 m->pindex = new_pindex; 1687 m->object = new_object; 1688 vm_page_unlock(m); 1689 vm_page_insert_radixdone(m, new_object, mpred); 1690 vm_page_dirty(m); 1691 return (0); 1692 } 1693 1694 /* 1695 * vm_page_alloc: 1696 * 1697 * Allocate and return a page that is associated with the specified 1698 * object and offset pair. By default, this page is exclusive busied. 1699 * 1700 * The caller must always specify an allocation class. 1701 * 1702 * allocation classes: 1703 * VM_ALLOC_NORMAL normal process request 1704 * VM_ALLOC_SYSTEM system *really* needs a page 1705 * VM_ALLOC_INTERRUPT interrupt time request 1706 * 1707 * optional allocation flags: 1708 * VM_ALLOC_COUNT(number) the number of additional pages that the caller 1709 * intends to allocate 1710 * VM_ALLOC_NOBUSY do not exclusive busy the page 1711 * VM_ALLOC_NODUMP do not include the page in a kernel core dump 1712 * VM_ALLOC_NOOBJ page is not associated with an object and 1713 * should not be exclusive busy 1714 * VM_ALLOC_SBUSY shared busy the allocated page 1715 * VM_ALLOC_WIRED wire the allocated page 1716 * VM_ALLOC_ZERO prefer a zeroed page 1717 */ 1718 vm_page_t 1719 vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req) 1720 { 1721 1722 return (vm_page_alloc_after(object, pindex, req, object != NULL ? 1723 vm_radix_lookup_le(&object->rtree, pindex) : NULL)); 1724 } 1725 1726 vm_page_t 1727 vm_page_alloc_domain(vm_object_t object, vm_pindex_t pindex, int domain, 1728 int req) 1729 { 1730 1731 return (vm_page_alloc_domain_after(object, pindex, domain, req, 1732 object != NULL ? vm_radix_lookup_le(&object->rtree, pindex) : 1733 NULL)); 1734 } 1735 1736 /* 1737 * Allocate a page in the specified object with the given page index. To 1738 * optimize insertion of the page into the object, the caller must also specifiy 1739 * the resident page in the object with largest index smaller than the given 1740 * page index, or NULL if no such page exists. 1741 */ 1742 vm_page_t 1743 vm_page_alloc_after(vm_object_t object, vm_pindex_t pindex, 1744 int req, vm_page_t mpred) 1745 { 1746 struct vm_domainset_iter di; 1747 vm_page_t m; 1748 int domain; 1749 1750 vm_domainset_iter_page_init(&di, object, pindex, &domain, &req); 1751 do { 1752 m = vm_page_alloc_domain_after(object, pindex, domain, req, 1753 mpred); 1754 if (m != NULL) 1755 break; 1756 } while (vm_domainset_iter_page(&di, object, &domain) == 0); 1757 1758 return (m); 1759 } 1760 1761 /* 1762 * Returns true if the number of free pages exceeds the minimum 1763 * for the request class and false otherwise. 1764 */ 1765 int 1766 vm_domain_allocate(struct vm_domain *vmd, int req, int npages) 1767 { 1768 u_int limit, old, new; 1769 1770 req = req & VM_ALLOC_CLASS_MASK; 1771 1772 /* 1773 * The page daemon is allowed to dig deeper into the free page list. 1774 */ 1775 if (curproc == pageproc && req != VM_ALLOC_INTERRUPT) 1776 req = VM_ALLOC_SYSTEM; 1777 if (req == VM_ALLOC_INTERRUPT) 1778 limit = 0; 1779 else if (req == VM_ALLOC_SYSTEM) 1780 limit = vmd->vmd_interrupt_free_min; 1781 else 1782 limit = vmd->vmd_free_reserved; 1783 1784 /* 1785 * Attempt to reserve the pages. Fail if we're below the limit. 1786 */ 1787 limit += npages; 1788 old = vmd->vmd_free_count; 1789 do { 1790 if (old < limit) 1791 return (0); 1792 new = old - npages; 1793 } while (atomic_fcmpset_int(&vmd->vmd_free_count, &old, new) == 0); 1794 1795 /* Wake the page daemon if we've crossed the threshold. */ 1796 if (vm_paging_needed(vmd, new) && !vm_paging_needed(vmd, old)) 1797 pagedaemon_wakeup(vmd->vmd_domain); 1798 1799 /* Only update bitsets on transitions. */ 1800 if ((old >= vmd->vmd_free_min && new < vmd->vmd_free_min) || 1801 (old >= vmd->vmd_free_severe && new < vmd->vmd_free_severe)) 1802 vm_domain_set(vmd); 1803 1804 return (1); 1805 } 1806 1807 vm_page_t 1808 vm_page_alloc_domain_after(vm_object_t object, vm_pindex_t pindex, int domain, 1809 int req, vm_page_t mpred) 1810 { 1811 struct vm_domain *vmd; 1812 vm_page_t m; 1813 int flags; 1814 1815 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) && 1816 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) && 1817 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 1818 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 1819 ("inconsistent object(%p)/req(%x)", object, req)); 1820 KASSERT(object == NULL || (req & VM_ALLOC_WAITOK) == 0, 1821 ("Can't sleep and retry object insertion.")); 1822 KASSERT(mpred == NULL || mpred->pindex < pindex, 1823 ("mpred %p doesn't precede pindex 0x%jx", mpred, 1824 (uintmax_t)pindex)); 1825 if (object != NULL) 1826 VM_OBJECT_ASSERT_WLOCKED(object); 1827 1828 again: 1829 m = NULL; 1830 #if VM_NRESERVLEVEL > 0 1831 /* 1832 * Can we allocate the page from a reservation? 1833 */ 1834 if (vm_object_reserv(object) && 1835 ((m = vm_reserv_extend(req, object, pindex, domain, mpred)) != NULL || 1836 (m = vm_reserv_alloc_page(req, object, pindex, domain, mpred)) != NULL)) { 1837 domain = vm_phys_domain(m); 1838 vmd = VM_DOMAIN(domain); 1839 goto found; 1840 } 1841 #endif 1842 vmd = VM_DOMAIN(domain); 1843 if (object != NULL && vmd->vmd_pgcache != NULL) { 1844 m = uma_zalloc(vmd->vmd_pgcache, M_NOWAIT); 1845 if (m != NULL) 1846 goto found; 1847 } 1848 if (vm_domain_allocate(vmd, req, 1)) { 1849 /* 1850 * If not, allocate it from the free page queues. 1851 */ 1852 vm_domain_free_lock(vmd); 1853 m = vm_phys_alloc_pages(domain, object != NULL ? 1854 VM_FREEPOOL_DEFAULT : VM_FREEPOOL_DIRECT, 0); 1855 vm_domain_free_unlock(vmd); 1856 if (m == NULL) { 1857 vm_domain_freecnt_inc(vmd, 1); 1858 #if VM_NRESERVLEVEL > 0 1859 if (vm_reserv_reclaim_inactive(domain)) 1860 goto again; 1861 #endif 1862 } 1863 } 1864 if (m == NULL) { 1865 /* 1866 * Not allocatable, give up. 1867 */ 1868 if (vm_domain_alloc_fail(vmd, object, req)) 1869 goto again; 1870 return (NULL); 1871 } 1872 1873 /* 1874 * At this point we had better have found a good page. 1875 */ 1876 KASSERT(m != NULL, ("missing page")); 1877 1878 found: 1879 vm_page_dequeue(m); 1880 vm_page_alloc_check(m); 1881 1882 /* 1883 * Initialize the page. Only the PG_ZERO flag is inherited. 1884 */ 1885 flags = 0; 1886 if ((req & VM_ALLOC_ZERO) != 0) 1887 flags = PG_ZERO; 1888 flags &= m->flags; 1889 if ((req & VM_ALLOC_NODUMP) != 0) 1890 flags |= PG_NODUMP; 1891 m->flags = flags; 1892 m->aflags = 0; 1893 m->oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ? 1894 VPO_UNMANAGED : 0; 1895 m->busy_lock = VPB_UNBUSIED; 1896 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0) 1897 m->busy_lock = VPB_SINGLE_EXCLUSIVER; 1898 if ((req & VM_ALLOC_SBUSY) != 0) 1899 m->busy_lock = VPB_SHARERS_WORD(1); 1900 if (req & VM_ALLOC_WIRED) { 1901 /* 1902 * The page lock is not required for wiring a page until that 1903 * page is inserted into the object. 1904 */ 1905 vm_wire_add(1); 1906 m->wire_count = 1; 1907 } 1908 m->act_count = 0; 1909 1910 if (object != NULL) { 1911 if (vm_page_insert_after(m, object, pindex, mpred)) { 1912 if (req & VM_ALLOC_WIRED) { 1913 vm_wire_sub(1); 1914 m->wire_count = 0; 1915 } 1916 KASSERT(m->object == NULL, ("page %p has object", m)); 1917 m->oflags = VPO_UNMANAGED; 1918 m->busy_lock = VPB_UNBUSIED; 1919 /* Don't change PG_ZERO. */ 1920 vm_page_free_toq(m); 1921 if (req & VM_ALLOC_WAITFAIL) { 1922 VM_OBJECT_WUNLOCK(object); 1923 vm_radix_wait(); 1924 VM_OBJECT_WLOCK(object); 1925 } 1926 return (NULL); 1927 } 1928 1929 /* Ignore device objects; the pager sets "memattr" for them. */ 1930 if (object->memattr != VM_MEMATTR_DEFAULT && 1931 (object->flags & OBJ_FICTITIOUS) == 0) 1932 pmap_page_set_memattr(m, object->memattr); 1933 } else 1934 m->pindex = pindex; 1935 1936 return (m); 1937 } 1938 1939 /* 1940 * vm_page_alloc_contig: 1941 * 1942 * Allocate a contiguous set of physical pages of the given size "npages" 1943 * from the free lists. All of the physical pages must be at or above 1944 * the given physical address "low" and below the given physical address 1945 * "high". The given value "alignment" determines the alignment of the 1946 * first physical page in the set. If the given value "boundary" is 1947 * non-zero, then the set of physical pages cannot cross any physical 1948 * address boundary that is a multiple of that value. Both "alignment" 1949 * and "boundary" must be a power of two. 1950 * 1951 * If the specified memory attribute, "memattr", is VM_MEMATTR_DEFAULT, 1952 * then the memory attribute setting for the physical pages is configured 1953 * to the object's memory attribute setting. Otherwise, the memory 1954 * attribute setting for the physical pages is configured to "memattr", 1955 * overriding the object's memory attribute setting. However, if the 1956 * object's memory attribute setting is not VM_MEMATTR_DEFAULT, then the 1957 * memory attribute setting for the physical pages cannot be configured 1958 * to VM_MEMATTR_DEFAULT. 1959 * 1960 * The specified object may not contain fictitious pages. 1961 * 1962 * The caller must always specify an allocation class. 1963 * 1964 * allocation classes: 1965 * VM_ALLOC_NORMAL normal process request 1966 * VM_ALLOC_SYSTEM system *really* needs a page 1967 * VM_ALLOC_INTERRUPT interrupt time request 1968 * 1969 * optional allocation flags: 1970 * VM_ALLOC_NOBUSY do not exclusive busy the page 1971 * VM_ALLOC_NODUMP do not include the page in a kernel core dump 1972 * VM_ALLOC_NOOBJ page is not associated with an object and 1973 * should not be exclusive busy 1974 * VM_ALLOC_SBUSY shared busy the allocated page 1975 * VM_ALLOC_WIRED wire the allocated page 1976 * VM_ALLOC_ZERO prefer a zeroed page 1977 */ 1978 vm_page_t 1979 vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req, 1980 u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, 1981 vm_paddr_t boundary, vm_memattr_t memattr) 1982 { 1983 struct vm_domainset_iter di; 1984 vm_page_t m; 1985 int domain; 1986 1987 vm_domainset_iter_page_init(&di, object, pindex, &domain, &req); 1988 do { 1989 m = vm_page_alloc_contig_domain(object, pindex, domain, req, 1990 npages, low, high, alignment, boundary, memattr); 1991 if (m != NULL) 1992 break; 1993 } while (vm_domainset_iter_page(&di, object, &domain) == 0); 1994 1995 return (m); 1996 } 1997 1998 vm_page_t 1999 vm_page_alloc_contig_domain(vm_object_t object, vm_pindex_t pindex, int domain, 2000 int req, u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, 2001 vm_paddr_t boundary, vm_memattr_t memattr) 2002 { 2003 struct vm_domain *vmd; 2004 vm_page_t m, m_ret, mpred; 2005 u_int busy_lock, flags, oflags; 2006 2007 mpred = NULL; /* XXX: pacify gcc */ 2008 KASSERT((object != NULL) == ((req & VM_ALLOC_NOOBJ) == 0) && 2009 (object != NULL || (req & VM_ALLOC_SBUSY) == 0) && 2010 ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 2011 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 2012 ("vm_page_alloc_contig: inconsistent object(%p)/req(%x)", object, 2013 req)); 2014 KASSERT(object == NULL || (req & VM_ALLOC_WAITOK) == 0, 2015 ("Can't sleep and retry object insertion.")); 2016 if (object != NULL) { 2017 VM_OBJECT_ASSERT_WLOCKED(object); 2018 KASSERT((object->flags & OBJ_FICTITIOUS) == 0, 2019 ("vm_page_alloc_contig: object %p has fictitious pages", 2020 object)); 2021 } 2022 KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero")); 2023 2024 if (object != NULL) { 2025 mpred = vm_radix_lookup_le(&object->rtree, pindex); 2026 KASSERT(mpred == NULL || mpred->pindex != pindex, 2027 ("vm_page_alloc_contig: pindex already allocated")); 2028 } 2029 2030 /* 2031 * Can we allocate the pages without the number of free pages falling 2032 * below the lower bound for the allocation class? 2033 */ 2034 again: 2035 #if VM_NRESERVLEVEL > 0 2036 /* 2037 * Can we allocate the pages from a reservation? 2038 */ 2039 if (vm_object_reserv(object) && 2040 ((m_ret = vm_reserv_extend_contig(req, object, pindex, domain, 2041 npages, low, high, alignment, boundary, mpred)) != NULL || 2042 (m_ret = vm_reserv_alloc_contig(req, object, pindex, domain, 2043 npages, low, high, alignment, boundary, mpred)) != NULL)) { 2044 domain = vm_phys_domain(m_ret); 2045 vmd = VM_DOMAIN(domain); 2046 goto found; 2047 } 2048 #endif 2049 m_ret = NULL; 2050 vmd = VM_DOMAIN(domain); 2051 if (vm_domain_allocate(vmd, req, npages)) { 2052 /* 2053 * allocate them from the free page queues. 2054 */ 2055 vm_domain_free_lock(vmd); 2056 m_ret = vm_phys_alloc_contig(domain, npages, low, high, 2057 alignment, boundary); 2058 vm_domain_free_unlock(vmd); 2059 if (m_ret == NULL) { 2060 vm_domain_freecnt_inc(vmd, npages); 2061 #if VM_NRESERVLEVEL > 0 2062 if (vm_reserv_reclaim_contig(domain, npages, low, 2063 high, alignment, boundary)) 2064 goto again; 2065 #endif 2066 } 2067 } 2068 if (m_ret == NULL) { 2069 if (vm_domain_alloc_fail(vmd, object, req)) 2070 goto again; 2071 return (NULL); 2072 } 2073 #if VM_NRESERVLEVEL > 0 2074 found: 2075 #endif 2076 for (m = m_ret; m < &m_ret[npages]; m++) { 2077 vm_page_dequeue(m); 2078 vm_page_alloc_check(m); 2079 } 2080 2081 /* 2082 * Initialize the pages. Only the PG_ZERO flag is inherited. 2083 */ 2084 flags = 0; 2085 if ((req & VM_ALLOC_ZERO) != 0) 2086 flags = PG_ZERO; 2087 if ((req & VM_ALLOC_NODUMP) != 0) 2088 flags |= PG_NODUMP; 2089 oflags = object == NULL || (object->flags & OBJ_UNMANAGED) != 0 ? 2090 VPO_UNMANAGED : 0; 2091 busy_lock = VPB_UNBUSIED; 2092 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_NOOBJ | VM_ALLOC_SBUSY)) == 0) 2093 busy_lock = VPB_SINGLE_EXCLUSIVER; 2094 if ((req & VM_ALLOC_SBUSY) != 0) 2095 busy_lock = VPB_SHARERS_WORD(1); 2096 if ((req & VM_ALLOC_WIRED) != 0) 2097 vm_wire_add(npages); 2098 if (object != NULL) { 2099 if (object->memattr != VM_MEMATTR_DEFAULT && 2100 memattr == VM_MEMATTR_DEFAULT) 2101 memattr = object->memattr; 2102 } 2103 for (m = m_ret; m < &m_ret[npages]; m++) { 2104 m->aflags = 0; 2105 m->flags = (m->flags | PG_NODUMP) & flags; 2106 m->busy_lock = busy_lock; 2107 if ((req & VM_ALLOC_WIRED) != 0) 2108 m->wire_count = 1; 2109 m->act_count = 0; 2110 m->oflags = oflags; 2111 if (object != NULL) { 2112 if (vm_page_insert_after(m, object, pindex, mpred)) { 2113 if ((req & VM_ALLOC_WIRED) != 0) 2114 vm_wire_sub(npages); 2115 KASSERT(m->object == NULL, 2116 ("page %p has object", m)); 2117 mpred = m; 2118 for (m = m_ret; m < &m_ret[npages]; m++) { 2119 if (m <= mpred && 2120 (req & VM_ALLOC_WIRED) != 0) 2121 m->wire_count = 0; 2122 m->oflags = VPO_UNMANAGED; 2123 m->busy_lock = VPB_UNBUSIED; 2124 /* Don't change PG_ZERO. */ 2125 vm_page_free_toq(m); 2126 } 2127 if (req & VM_ALLOC_WAITFAIL) { 2128 VM_OBJECT_WUNLOCK(object); 2129 vm_radix_wait(); 2130 VM_OBJECT_WLOCK(object); 2131 } 2132 return (NULL); 2133 } 2134 mpred = m; 2135 } else 2136 m->pindex = pindex; 2137 if (memattr != VM_MEMATTR_DEFAULT) 2138 pmap_page_set_memattr(m, memattr); 2139 pindex++; 2140 } 2141 return (m_ret); 2142 } 2143 2144 /* 2145 * Check a page that has been freshly dequeued from a freelist. 2146 */ 2147 static void 2148 vm_page_alloc_check(vm_page_t m) 2149 { 2150 2151 KASSERT(m->object == NULL, ("page %p has object", m)); 2152 KASSERT(m->queue == PQ_NONE && (m->aflags & PGA_QUEUE_STATE_MASK) == 0, 2153 ("page %p has unexpected queue %d, flags %#x", 2154 m, m->queue, (m->aflags & PGA_QUEUE_STATE_MASK))); 2155 KASSERT(!vm_page_held(m), ("page %p is held", m)); 2156 KASSERT(!vm_page_busied(m), ("page %p is busy", m)); 2157 KASSERT(m->dirty == 0, ("page %p is dirty", m)); 2158 KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, 2159 ("page %p has unexpected memattr %d", 2160 m, pmap_page_get_memattr(m))); 2161 KASSERT(m->valid == 0, ("free page %p is valid", m)); 2162 } 2163 2164 /* 2165 * vm_page_alloc_freelist: 2166 * 2167 * Allocate a physical page from the specified free page list. 2168 * 2169 * The caller must always specify an allocation class. 2170 * 2171 * allocation classes: 2172 * VM_ALLOC_NORMAL normal process request 2173 * VM_ALLOC_SYSTEM system *really* needs a page 2174 * VM_ALLOC_INTERRUPT interrupt time request 2175 * 2176 * optional allocation flags: 2177 * VM_ALLOC_COUNT(number) the number of additional pages that the caller 2178 * intends to allocate 2179 * VM_ALLOC_WIRED wire the allocated page 2180 * VM_ALLOC_ZERO prefer a zeroed page 2181 */ 2182 vm_page_t 2183 vm_page_alloc_freelist(int freelist, int req) 2184 { 2185 struct vm_domainset_iter di; 2186 vm_page_t m; 2187 int domain; 2188 2189 vm_domainset_iter_page_init(&di, NULL, 0, &domain, &req); 2190 do { 2191 m = vm_page_alloc_freelist_domain(domain, freelist, req); 2192 if (m != NULL) 2193 break; 2194 } while (vm_domainset_iter_page(&di, NULL, &domain) == 0); 2195 2196 return (m); 2197 } 2198 2199 vm_page_t 2200 vm_page_alloc_freelist_domain(int domain, int freelist, int req) 2201 { 2202 struct vm_domain *vmd; 2203 vm_page_t m; 2204 u_int flags; 2205 2206 m = NULL; 2207 vmd = VM_DOMAIN(domain); 2208 again: 2209 if (vm_domain_allocate(vmd, req, 1)) { 2210 vm_domain_free_lock(vmd); 2211 m = vm_phys_alloc_freelist_pages(domain, freelist, 2212 VM_FREEPOOL_DIRECT, 0); 2213 vm_domain_free_unlock(vmd); 2214 if (m == NULL) 2215 vm_domain_freecnt_inc(vmd, 1); 2216 } 2217 if (m == NULL) { 2218 if (vm_domain_alloc_fail(vmd, NULL, req)) 2219 goto again; 2220 return (NULL); 2221 } 2222 vm_page_dequeue(m); 2223 vm_page_alloc_check(m); 2224 2225 /* 2226 * Initialize the page. Only the PG_ZERO flag is inherited. 2227 */ 2228 m->aflags = 0; 2229 flags = 0; 2230 if ((req & VM_ALLOC_ZERO) != 0) 2231 flags = PG_ZERO; 2232 m->flags &= flags; 2233 if ((req & VM_ALLOC_WIRED) != 0) { 2234 /* 2235 * The page lock is not required for wiring a page that does 2236 * not belong to an object. 2237 */ 2238 vm_wire_add(1); 2239 m->wire_count = 1; 2240 } 2241 /* Unmanaged pages don't use "act_count". */ 2242 m->oflags = VPO_UNMANAGED; 2243 return (m); 2244 } 2245 2246 static int 2247 vm_page_import(void *arg, void **store, int cnt, int domain, int flags) 2248 { 2249 struct vm_domain *vmd; 2250 int i; 2251 2252 vmd = arg; 2253 /* Only import if we can bring in a full bucket. */ 2254 if (cnt == 1 || !vm_domain_allocate(vmd, VM_ALLOC_NORMAL, cnt)) 2255 return (0); 2256 domain = vmd->vmd_domain; 2257 vm_domain_free_lock(vmd); 2258 i = vm_phys_alloc_npages(domain, VM_FREEPOOL_DEFAULT, cnt, 2259 (vm_page_t *)store); 2260 vm_domain_free_unlock(vmd); 2261 if (cnt != i) 2262 vm_domain_freecnt_inc(vmd, cnt - i); 2263 2264 return (i); 2265 } 2266 2267 static void 2268 vm_page_release(void *arg, void **store, int cnt) 2269 { 2270 struct vm_domain *vmd; 2271 vm_page_t m; 2272 int i; 2273 2274 vmd = arg; 2275 vm_domain_free_lock(vmd); 2276 for (i = 0; i < cnt; i++) { 2277 m = (vm_page_t)store[i]; 2278 vm_phys_free_pages(m, 0); 2279 } 2280 vm_domain_free_unlock(vmd); 2281 vm_domain_freecnt_inc(vmd, cnt); 2282 } 2283 2284 #define VPSC_ANY 0 /* No restrictions. */ 2285 #define VPSC_NORESERV 1 /* Skip reservations; implies VPSC_NOSUPER. */ 2286 #define VPSC_NOSUPER 2 /* Skip superpages. */ 2287 2288 /* 2289 * vm_page_scan_contig: 2290 * 2291 * Scan vm_page_array[] between the specified entries "m_start" and 2292 * "m_end" for a run of contiguous physical pages that satisfy the 2293 * specified conditions, and return the lowest page in the run. The 2294 * specified "alignment" determines the alignment of the lowest physical 2295 * page in the run. If the specified "boundary" is non-zero, then the 2296 * run of physical pages cannot span a physical address that is a 2297 * multiple of "boundary". 2298 * 2299 * "m_end" is never dereferenced, so it need not point to a vm_page 2300 * structure within vm_page_array[]. 2301 * 2302 * "npages" must be greater than zero. "m_start" and "m_end" must not 2303 * span a hole (or discontiguity) in the physical address space. Both 2304 * "alignment" and "boundary" must be a power of two. 2305 */ 2306 vm_page_t 2307 vm_page_scan_contig(u_long npages, vm_page_t m_start, vm_page_t m_end, 2308 u_long alignment, vm_paddr_t boundary, int options) 2309 { 2310 struct mtx *m_mtx; 2311 vm_object_t object; 2312 vm_paddr_t pa; 2313 vm_page_t m, m_run; 2314 #if VM_NRESERVLEVEL > 0 2315 int level; 2316 #endif 2317 int m_inc, order, run_ext, run_len; 2318 2319 KASSERT(npages > 0, ("npages is 0")); 2320 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 2321 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 2322 m_run = NULL; 2323 run_len = 0; 2324 m_mtx = NULL; 2325 for (m = m_start; m < m_end && run_len < npages; m += m_inc) { 2326 KASSERT((m->flags & PG_MARKER) == 0, 2327 ("page %p is PG_MARKER", m)); 2328 KASSERT((m->flags & PG_FICTITIOUS) == 0 || m->wire_count == 1, 2329 ("fictitious page %p has invalid wire count", m)); 2330 2331 /* 2332 * If the current page would be the start of a run, check its 2333 * physical address against the end, alignment, and boundary 2334 * conditions. If it doesn't satisfy these conditions, either 2335 * terminate the scan or advance to the next page that 2336 * satisfies the failed condition. 2337 */ 2338 if (run_len == 0) { 2339 KASSERT(m_run == NULL, ("m_run != NULL")); 2340 if (m + npages > m_end) 2341 break; 2342 pa = VM_PAGE_TO_PHYS(m); 2343 if ((pa & (alignment - 1)) != 0) { 2344 m_inc = atop(roundup2(pa, alignment) - pa); 2345 continue; 2346 } 2347 if (rounddown2(pa ^ (pa + ptoa(npages) - 1), 2348 boundary) != 0) { 2349 m_inc = atop(roundup2(pa, boundary) - pa); 2350 continue; 2351 } 2352 } else 2353 KASSERT(m_run != NULL, ("m_run == NULL")); 2354 2355 vm_page_change_lock(m, &m_mtx); 2356 m_inc = 1; 2357 retry: 2358 if (vm_page_held(m)) 2359 run_ext = 0; 2360 #if VM_NRESERVLEVEL > 0 2361 else if ((level = vm_reserv_level(m)) >= 0 && 2362 (options & VPSC_NORESERV) != 0) { 2363 run_ext = 0; 2364 /* Advance to the end of the reservation. */ 2365 pa = VM_PAGE_TO_PHYS(m); 2366 m_inc = atop(roundup2(pa + 1, vm_reserv_size(level)) - 2367 pa); 2368 } 2369 #endif 2370 else if ((object = m->object) != NULL) { 2371 /* 2372 * The page is considered eligible for relocation if 2373 * and only if it could be laundered or reclaimed by 2374 * the page daemon. 2375 */ 2376 if (!VM_OBJECT_TRYRLOCK(object)) { 2377 mtx_unlock(m_mtx); 2378 VM_OBJECT_RLOCK(object); 2379 mtx_lock(m_mtx); 2380 if (m->object != object) { 2381 /* 2382 * The page may have been freed. 2383 */ 2384 VM_OBJECT_RUNLOCK(object); 2385 goto retry; 2386 } else if (vm_page_held(m)) { 2387 run_ext = 0; 2388 goto unlock; 2389 } 2390 } 2391 KASSERT((m->flags & PG_UNHOLDFREE) == 0, 2392 ("page %p is PG_UNHOLDFREE", m)); 2393 /* Don't care: PG_NODUMP, PG_ZERO. */ 2394 if (object->type != OBJT_DEFAULT && 2395 object->type != OBJT_SWAP && 2396 object->type != OBJT_VNODE) { 2397 run_ext = 0; 2398 #if VM_NRESERVLEVEL > 0 2399 } else if ((options & VPSC_NOSUPER) != 0 && 2400 (level = vm_reserv_level_iffullpop(m)) >= 0) { 2401 run_ext = 0; 2402 /* Advance to the end of the superpage. */ 2403 pa = VM_PAGE_TO_PHYS(m); 2404 m_inc = atop(roundup2(pa + 1, 2405 vm_reserv_size(level)) - pa); 2406 #endif 2407 } else if (object->memattr == VM_MEMATTR_DEFAULT && 2408 vm_page_queue(m) != PQ_NONE && !vm_page_busied(m)) { 2409 /* 2410 * The page is allocated but eligible for 2411 * relocation. Extend the current run by one 2412 * page. 2413 */ 2414 KASSERT(pmap_page_get_memattr(m) == 2415 VM_MEMATTR_DEFAULT, 2416 ("page %p has an unexpected memattr", m)); 2417 KASSERT((m->oflags & (VPO_SWAPINPROG | 2418 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, 2419 ("page %p has unexpected oflags", m)); 2420 /* Don't care: VPO_NOSYNC. */ 2421 run_ext = 1; 2422 } else 2423 run_ext = 0; 2424 unlock: 2425 VM_OBJECT_RUNLOCK(object); 2426 #if VM_NRESERVLEVEL > 0 2427 } else if (level >= 0) { 2428 /* 2429 * The page is reserved but not yet allocated. In 2430 * other words, it is still free. Extend the current 2431 * run by one page. 2432 */ 2433 run_ext = 1; 2434 #endif 2435 } else if ((order = m->order) < VM_NFREEORDER) { 2436 /* 2437 * The page is enqueued in the physical memory 2438 * allocator's free page queues. Moreover, it is the 2439 * first page in a power-of-two-sized run of 2440 * contiguous free pages. Add these pages to the end 2441 * of the current run, and jump ahead. 2442 */ 2443 run_ext = 1 << order; 2444 m_inc = 1 << order; 2445 } else { 2446 /* 2447 * Skip the page for one of the following reasons: (1) 2448 * It is enqueued in the physical memory allocator's 2449 * free page queues. However, it is not the first 2450 * page in a run of contiguous free pages. (This case 2451 * rarely occurs because the scan is performed in 2452 * ascending order.) (2) It is not reserved, and it is 2453 * transitioning from free to allocated. (Conversely, 2454 * the transition from allocated to free for managed 2455 * pages is blocked by the page lock.) (3) It is 2456 * allocated but not contained by an object and not 2457 * wired, e.g., allocated by Xen's balloon driver. 2458 */ 2459 run_ext = 0; 2460 } 2461 2462 /* 2463 * Extend or reset the current run of pages. 2464 */ 2465 if (run_ext > 0) { 2466 if (run_len == 0) 2467 m_run = m; 2468 run_len += run_ext; 2469 } else { 2470 if (run_len > 0) { 2471 m_run = NULL; 2472 run_len = 0; 2473 } 2474 } 2475 } 2476 if (m_mtx != NULL) 2477 mtx_unlock(m_mtx); 2478 if (run_len >= npages) 2479 return (m_run); 2480 return (NULL); 2481 } 2482 2483 /* 2484 * vm_page_reclaim_run: 2485 * 2486 * Try to relocate each of the allocated virtual pages within the 2487 * specified run of physical pages to a new physical address. Free the 2488 * physical pages underlying the relocated virtual pages. A virtual page 2489 * is relocatable if and only if it could be laundered or reclaimed by 2490 * the page daemon. Whenever possible, a virtual page is relocated to a 2491 * physical address above "high". 2492 * 2493 * Returns 0 if every physical page within the run was already free or 2494 * just freed by a successful relocation. Otherwise, returns a non-zero 2495 * value indicating why the last attempt to relocate a virtual page was 2496 * unsuccessful. 2497 * 2498 * "req_class" must be an allocation class. 2499 */ 2500 static int 2501 vm_page_reclaim_run(int req_class, int domain, u_long npages, vm_page_t m_run, 2502 vm_paddr_t high) 2503 { 2504 struct vm_domain *vmd; 2505 struct mtx *m_mtx; 2506 struct spglist free; 2507 vm_object_t object; 2508 vm_paddr_t pa; 2509 vm_page_t m, m_end, m_new; 2510 int error, order, req; 2511 2512 KASSERT((req_class & VM_ALLOC_CLASS_MASK) == req_class, 2513 ("req_class is not an allocation class")); 2514 SLIST_INIT(&free); 2515 error = 0; 2516 m = m_run; 2517 m_end = m_run + npages; 2518 m_mtx = NULL; 2519 for (; error == 0 && m < m_end; m++) { 2520 KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0, 2521 ("page %p is PG_FICTITIOUS or PG_MARKER", m)); 2522 2523 /* 2524 * Avoid releasing and reacquiring the same page lock. 2525 */ 2526 vm_page_change_lock(m, &m_mtx); 2527 retry: 2528 if (vm_page_held(m)) 2529 error = EBUSY; 2530 else if ((object = m->object) != NULL) { 2531 /* 2532 * The page is relocated if and only if it could be 2533 * laundered or reclaimed by the page daemon. 2534 */ 2535 if (!VM_OBJECT_TRYWLOCK(object)) { 2536 mtx_unlock(m_mtx); 2537 VM_OBJECT_WLOCK(object); 2538 mtx_lock(m_mtx); 2539 if (m->object != object) { 2540 /* 2541 * The page may have been freed. 2542 */ 2543 VM_OBJECT_WUNLOCK(object); 2544 goto retry; 2545 } else if (vm_page_held(m)) { 2546 error = EBUSY; 2547 goto unlock; 2548 } 2549 } 2550 KASSERT((m->flags & PG_UNHOLDFREE) == 0, 2551 ("page %p is PG_UNHOLDFREE", m)); 2552 /* Don't care: PG_NODUMP, PG_ZERO. */ 2553 if (object->type != OBJT_DEFAULT && 2554 object->type != OBJT_SWAP && 2555 object->type != OBJT_VNODE) 2556 error = EINVAL; 2557 else if (object->memattr != VM_MEMATTR_DEFAULT) 2558 error = EINVAL; 2559 else if (vm_page_queue(m) != PQ_NONE && 2560 !vm_page_busied(m)) { 2561 KASSERT(pmap_page_get_memattr(m) == 2562 VM_MEMATTR_DEFAULT, 2563 ("page %p has an unexpected memattr", m)); 2564 KASSERT((m->oflags & (VPO_SWAPINPROG | 2565 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, 2566 ("page %p has unexpected oflags", m)); 2567 /* Don't care: VPO_NOSYNC. */ 2568 if (m->valid != 0) { 2569 /* 2570 * First, try to allocate a new page 2571 * that is above "high". Failing 2572 * that, try to allocate a new page 2573 * that is below "m_run". Allocate 2574 * the new page between the end of 2575 * "m_run" and "high" only as a last 2576 * resort. 2577 */ 2578 req = req_class | VM_ALLOC_NOOBJ; 2579 if ((m->flags & PG_NODUMP) != 0) 2580 req |= VM_ALLOC_NODUMP; 2581 if (trunc_page(high) != 2582 ~(vm_paddr_t)PAGE_MASK) { 2583 m_new = vm_page_alloc_contig( 2584 NULL, 0, req, 1, 2585 round_page(high), 2586 ~(vm_paddr_t)0, 2587 PAGE_SIZE, 0, 2588 VM_MEMATTR_DEFAULT); 2589 } else 2590 m_new = NULL; 2591 if (m_new == NULL) { 2592 pa = VM_PAGE_TO_PHYS(m_run); 2593 m_new = vm_page_alloc_contig( 2594 NULL, 0, req, 1, 2595 0, pa - 1, PAGE_SIZE, 0, 2596 VM_MEMATTR_DEFAULT); 2597 } 2598 if (m_new == NULL) { 2599 pa += ptoa(npages); 2600 m_new = vm_page_alloc_contig( 2601 NULL, 0, req, 1, 2602 pa, high, PAGE_SIZE, 0, 2603 VM_MEMATTR_DEFAULT); 2604 } 2605 if (m_new == NULL) { 2606 error = ENOMEM; 2607 goto unlock; 2608 } 2609 KASSERT(m_new->wire_count == 0, 2610 ("page %p is wired", m_new)); 2611 2612 /* 2613 * Replace "m" with the new page. For 2614 * vm_page_replace(), "m" must be busy 2615 * and dequeued. Finally, change "m" 2616 * as if vm_page_free() was called. 2617 */ 2618 if (object->ref_count != 0) 2619 pmap_remove_all(m); 2620 m_new->aflags = m->aflags & 2621 ~PGA_QUEUE_STATE_MASK; 2622 KASSERT(m_new->oflags == VPO_UNMANAGED, 2623 ("page %p is managed", m_new)); 2624 m_new->oflags = m->oflags & VPO_NOSYNC; 2625 pmap_copy_page(m, m_new); 2626 m_new->valid = m->valid; 2627 m_new->dirty = m->dirty; 2628 m->flags &= ~PG_ZERO; 2629 vm_page_xbusy(m); 2630 vm_page_dequeue(m); 2631 vm_page_replace_checked(m_new, object, 2632 m->pindex, m); 2633 if (vm_page_free_prep(m)) 2634 SLIST_INSERT_HEAD(&free, m, 2635 plinks.s.ss); 2636 2637 /* 2638 * The new page must be deactivated 2639 * before the object is unlocked. 2640 */ 2641 vm_page_change_lock(m_new, &m_mtx); 2642 vm_page_deactivate(m_new); 2643 } else { 2644 m->flags &= ~PG_ZERO; 2645 vm_page_dequeue(m); 2646 vm_page_remove(m); 2647 if (vm_page_free_prep(m)) 2648 SLIST_INSERT_HEAD(&free, m, 2649 plinks.s.ss); 2650 KASSERT(m->dirty == 0, 2651 ("page %p is dirty", m)); 2652 } 2653 } else 2654 error = EBUSY; 2655 unlock: 2656 VM_OBJECT_WUNLOCK(object); 2657 } else { 2658 MPASS(vm_phys_domain(m) == domain); 2659 vmd = VM_DOMAIN(domain); 2660 vm_domain_free_lock(vmd); 2661 order = m->order; 2662 if (order < VM_NFREEORDER) { 2663 /* 2664 * The page is enqueued in the physical memory 2665 * allocator's free page queues. Moreover, it 2666 * is the first page in a power-of-two-sized 2667 * run of contiguous free pages. Jump ahead 2668 * to the last page within that run, and 2669 * continue from there. 2670 */ 2671 m += (1 << order) - 1; 2672 } 2673 #if VM_NRESERVLEVEL > 0 2674 else if (vm_reserv_is_page_free(m)) 2675 order = 0; 2676 #endif 2677 vm_domain_free_unlock(vmd); 2678 if (order == VM_NFREEORDER) 2679 error = EINVAL; 2680 } 2681 } 2682 if (m_mtx != NULL) 2683 mtx_unlock(m_mtx); 2684 if ((m = SLIST_FIRST(&free)) != NULL) { 2685 int cnt; 2686 2687 vmd = VM_DOMAIN(domain); 2688 cnt = 0; 2689 vm_domain_free_lock(vmd); 2690 do { 2691 MPASS(vm_phys_domain(m) == domain); 2692 SLIST_REMOVE_HEAD(&free, plinks.s.ss); 2693 vm_phys_free_pages(m, 0); 2694 cnt++; 2695 } while ((m = SLIST_FIRST(&free)) != NULL); 2696 vm_domain_free_unlock(vmd); 2697 vm_domain_freecnt_inc(vmd, cnt); 2698 } 2699 return (error); 2700 } 2701 2702 #define NRUNS 16 2703 2704 CTASSERT(powerof2(NRUNS)); 2705 2706 #define RUN_INDEX(count) ((count) & (NRUNS - 1)) 2707 2708 #define MIN_RECLAIM 8 2709 2710 /* 2711 * vm_page_reclaim_contig: 2712 * 2713 * Reclaim allocated, contiguous physical memory satisfying the specified 2714 * conditions by relocating the virtual pages using that physical memory. 2715 * Returns true if reclamation is successful and false otherwise. Since 2716 * relocation requires the allocation of physical pages, reclamation may 2717 * fail due to a shortage of free pages. When reclamation fails, callers 2718 * are expected to perform vm_wait() before retrying a failed allocation 2719 * operation, e.g., vm_page_alloc_contig(). 2720 * 2721 * The caller must always specify an allocation class through "req". 2722 * 2723 * allocation classes: 2724 * VM_ALLOC_NORMAL normal process request 2725 * VM_ALLOC_SYSTEM system *really* needs a page 2726 * VM_ALLOC_INTERRUPT interrupt time request 2727 * 2728 * The optional allocation flags are ignored. 2729 * 2730 * "npages" must be greater than zero. Both "alignment" and "boundary" 2731 * must be a power of two. 2732 */ 2733 bool 2734 vm_page_reclaim_contig_domain(int domain, int req, u_long npages, 2735 vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary) 2736 { 2737 struct vm_domain *vmd; 2738 vm_paddr_t curr_low; 2739 vm_page_t m_run, m_runs[NRUNS]; 2740 u_long count, reclaimed; 2741 int error, i, options, req_class; 2742 2743 KASSERT(npages > 0, ("npages is 0")); 2744 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 2745 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 2746 req_class = req & VM_ALLOC_CLASS_MASK; 2747 2748 /* 2749 * The page daemon is allowed to dig deeper into the free page list. 2750 */ 2751 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 2752 req_class = VM_ALLOC_SYSTEM; 2753 2754 /* 2755 * Return if the number of free pages cannot satisfy the requested 2756 * allocation. 2757 */ 2758 vmd = VM_DOMAIN(domain); 2759 count = vmd->vmd_free_count; 2760 if (count < npages + vmd->vmd_free_reserved || (count < npages + 2761 vmd->vmd_interrupt_free_min && req_class == VM_ALLOC_SYSTEM) || 2762 (count < npages && req_class == VM_ALLOC_INTERRUPT)) 2763 return (false); 2764 2765 /* 2766 * Scan up to three times, relaxing the restrictions ("options") on 2767 * the reclamation of reservations and superpages each time. 2768 */ 2769 for (options = VPSC_NORESERV;;) { 2770 /* 2771 * Find the highest runs that satisfy the given constraints 2772 * and restrictions, and record them in "m_runs". 2773 */ 2774 curr_low = low; 2775 count = 0; 2776 for (;;) { 2777 m_run = vm_phys_scan_contig(domain, npages, curr_low, 2778 high, alignment, boundary, options); 2779 if (m_run == NULL) 2780 break; 2781 curr_low = VM_PAGE_TO_PHYS(m_run) + ptoa(npages); 2782 m_runs[RUN_INDEX(count)] = m_run; 2783 count++; 2784 } 2785 2786 /* 2787 * Reclaim the highest runs in LIFO (descending) order until 2788 * the number of reclaimed pages, "reclaimed", is at least 2789 * MIN_RECLAIM. Reset "reclaimed" each time because each 2790 * reclamation is idempotent, and runs will (likely) recur 2791 * from one scan to the next as restrictions are relaxed. 2792 */ 2793 reclaimed = 0; 2794 for (i = 0; count > 0 && i < NRUNS; i++) { 2795 count--; 2796 m_run = m_runs[RUN_INDEX(count)]; 2797 error = vm_page_reclaim_run(req_class, domain, npages, 2798 m_run, high); 2799 if (error == 0) { 2800 reclaimed += npages; 2801 if (reclaimed >= MIN_RECLAIM) 2802 return (true); 2803 } 2804 } 2805 2806 /* 2807 * Either relax the restrictions on the next scan or return if 2808 * the last scan had no restrictions. 2809 */ 2810 if (options == VPSC_NORESERV) 2811 options = VPSC_NOSUPER; 2812 else if (options == VPSC_NOSUPER) 2813 options = VPSC_ANY; 2814 else if (options == VPSC_ANY) 2815 return (reclaimed != 0); 2816 } 2817 } 2818 2819 bool 2820 vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low, vm_paddr_t high, 2821 u_long alignment, vm_paddr_t boundary) 2822 { 2823 struct vm_domainset_iter di; 2824 int domain; 2825 bool ret; 2826 2827 vm_domainset_iter_page_init(&di, NULL, 0, &domain, &req); 2828 do { 2829 ret = vm_page_reclaim_contig_domain(domain, req, npages, low, 2830 high, alignment, boundary); 2831 if (ret) 2832 break; 2833 } while (vm_domainset_iter_page(&di, NULL, &domain) == 0); 2834 2835 return (ret); 2836 } 2837 2838 /* 2839 * Set the domain in the appropriate page level domainset. 2840 */ 2841 void 2842 vm_domain_set(struct vm_domain *vmd) 2843 { 2844 2845 mtx_lock(&vm_domainset_lock); 2846 if (!vmd->vmd_minset && vm_paging_min(vmd)) { 2847 vmd->vmd_minset = 1; 2848 DOMAINSET_SET(vmd->vmd_domain, &vm_min_domains); 2849 } 2850 if (!vmd->vmd_severeset && vm_paging_severe(vmd)) { 2851 vmd->vmd_severeset = 1; 2852 DOMAINSET_SET(vmd->vmd_domain, &vm_severe_domains); 2853 } 2854 mtx_unlock(&vm_domainset_lock); 2855 } 2856 2857 /* 2858 * Clear the domain from the appropriate page level domainset. 2859 */ 2860 void 2861 vm_domain_clear(struct vm_domain *vmd) 2862 { 2863 2864 mtx_lock(&vm_domainset_lock); 2865 if (vmd->vmd_minset && !vm_paging_min(vmd)) { 2866 vmd->vmd_minset = 0; 2867 DOMAINSET_CLR(vmd->vmd_domain, &vm_min_domains); 2868 if (vm_min_waiters != 0) { 2869 vm_min_waiters = 0; 2870 wakeup(&vm_min_domains); 2871 } 2872 } 2873 if (vmd->vmd_severeset && !vm_paging_severe(vmd)) { 2874 vmd->vmd_severeset = 0; 2875 DOMAINSET_CLR(vmd->vmd_domain, &vm_severe_domains); 2876 if (vm_severe_waiters != 0) { 2877 vm_severe_waiters = 0; 2878 wakeup(&vm_severe_domains); 2879 } 2880 } 2881 2882 /* 2883 * If pageout daemon needs pages, then tell it that there are 2884 * some free. 2885 */ 2886 if (vmd->vmd_pageout_pages_needed && 2887 vmd->vmd_free_count >= vmd->vmd_pageout_free_min) { 2888 wakeup(&vmd->vmd_pageout_pages_needed); 2889 vmd->vmd_pageout_pages_needed = 0; 2890 } 2891 2892 /* See comments in vm_wait_doms(). */ 2893 if (vm_pageproc_waiters) { 2894 vm_pageproc_waiters = 0; 2895 wakeup(&vm_pageproc_waiters); 2896 } 2897 mtx_unlock(&vm_domainset_lock); 2898 } 2899 2900 /* 2901 * Wait for free pages to exceed the min threshold globally. 2902 */ 2903 void 2904 vm_wait_min(void) 2905 { 2906 2907 mtx_lock(&vm_domainset_lock); 2908 while (vm_page_count_min()) { 2909 vm_min_waiters++; 2910 msleep(&vm_min_domains, &vm_domainset_lock, PVM, "vmwait", 0); 2911 } 2912 mtx_unlock(&vm_domainset_lock); 2913 } 2914 2915 /* 2916 * Wait for free pages to exceed the severe threshold globally. 2917 */ 2918 void 2919 vm_wait_severe(void) 2920 { 2921 2922 mtx_lock(&vm_domainset_lock); 2923 while (vm_page_count_severe()) { 2924 vm_severe_waiters++; 2925 msleep(&vm_severe_domains, &vm_domainset_lock, PVM, 2926 "vmwait", 0); 2927 } 2928 mtx_unlock(&vm_domainset_lock); 2929 } 2930 2931 u_int 2932 vm_wait_count(void) 2933 { 2934 2935 return (vm_severe_waiters + vm_min_waiters + vm_pageproc_waiters); 2936 } 2937 2938 void 2939 vm_wait_doms(const domainset_t *wdoms) 2940 { 2941 2942 /* 2943 * We use racey wakeup synchronization to avoid expensive global 2944 * locking for the pageproc when sleeping with a non-specific vm_wait. 2945 * To handle this, we only sleep for one tick in this instance. It 2946 * is expected that most allocations for the pageproc will come from 2947 * kmem or vm_page_grab* which will use the more specific and 2948 * race-free vm_wait_domain(). 2949 */ 2950 if (curproc == pageproc) { 2951 mtx_lock(&vm_domainset_lock); 2952 vm_pageproc_waiters++; 2953 msleep(&vm_pageproc_waiters, &vm_domainset_lock, PVM | PDROP, 2954 "pageprocwait", 1); 2955 } else { 2956 /* 2957 * XXX Ideally we would wait only until the allocation could 2958 * be satisfied. This condition can cause new allocators to 2959 * consume all freed pages while old allocators wait. 2960 */ 2961 mtx_lock(&vm_domainset_lock); 2962 if (vm_page_count_min_set(wdoms)) { 2963 vm_min_waiters++; 2964 msleep(&vm_min_domains, &vm_domainset_lock, 2965 PVM | PDROP, "vmwait", 0); 2966 } else 2967 mtx_unlock(&vm_domainset_lock); 2968 } 2969 } 2970 2971 /* 2972 * vm_wait_domain: 2973 * 2974 * Sleep until free pages are available for allocation. 2975 * - Called in various places after failed memory allocations. 2976 */ 2977 void 2978 vm_wait_domain(int domain) 2979 { 2980 struct vm_domain *vmd; 2981 domainset_t wdom; 2982 2983 vmd = VM_DOMAIN(domain); 2984 vm_domain_free_assert_unlocked(vmd); 2985 2986 if (curproc == pageproc) { 2987 mtx_lock(&vm_domainset_lock); 2988 if (vmd->vmd_free_count < vmd->vmd_pageout_free_min) { 2989 vmd->vmd_pageout_pages_needed = 1; 2990 msleep(&vmd->vmd_pageout_pages_needed, 2991 &vm_domainset_lock, PDROP | PSWP, "VMWait", 0); 2992 } else 2993 mtx_unlock(&vm_domainset_lock); 2994 } else { 2995 if (pageproc == NULL) 2996 panic("vm_wait in early boot"); 2997 DOMAINSET_ZERO(&wdom); 2998 DOMAINSET_SET(vmd->vmd_domain, &wdom); 2999 vm_wait_doms(&wdom); 3000 } 3001 } 3002 3003 /* 3004 * vm_wait: 3005 * 3006 * Sleep until free pages are available for allocation in the 3007 * affinity domains of the obj. If obj is NULL, the domain set 3008 * for the calling thread is used. 3009 * Called in various places after failed memory allocations. 3010 */ 3011 void 3012 vm_wait(vm_object_t obj) 3013 { 3014 struct domainset *d; 3015 3016 d = NULL; 3017 3018 /* 3019 * Carefully fetch pointers only once: the struct domainset 3020 * itself is ummutable but the pointer might change. 3021 */ 3022 if (obj != NULL) 3023 d = obj->domain.dr_policy; 3024 if (d == NULL) 3025 d = curthread->td_domain.dr_policy; 3026 3027 vm_wait_doms(&d->ds_mask); 3028 } 3029 3030 /* 3031 * vm_domain_alloc_fail: 3032 * 3033 * Called when a page allocation function fails. Informs the 3034 * pagedaemon and performs the requested wait. Requires the 3035 * domain_free and object lock on entry. Returns with the 3036 * object lock held and free lock released. Returns an error when 3037 * retry is necessary. 3038 * 3039 */ 3040 static int 3041 vm_domain_alloc_fail(struct vm_domain *vmd, vm_object_t object, int req) 3042 { 3043 3044 vm_domain_free_assert_unlocked(vmd); 3045 3046 atomic_add_int(&vmd->vmd_pageout_deficit, 3047 max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1)); 3048 if (req & (VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL)) { 3049 if (object != NULL) 3050 VM_OBJECT_WUNLOCK(object); 3051 vm_wait_domain(vmd->vmd_domain); 3052 if (object != NULL) 3053 VM_OBJECT_WLOCK(object); 3054 if (req & VM_ALLOC_WAITOK) 3055 return (EAGAIN); 3056 } 3057 3058 return (0); 3059 } 3060 3061 /* 3062 * vm_waitpfault: 3063 * 3064 * Sleep until free pages are available for allocation. 3065 * - Called only in vm_fault so that processes page faulting 3066 * can be easily tracked. 3067 * - Sleeps at a lower priority than vm_wait() so that vm_wait()ing 3068 * processes will be able to grab memory first. Do not change 3069 * this balance without careful testing first. 3070 */ 3071 void 3072 vm_waitpfault(struct domainset *dset) 3073 { 3074 3075 /* 3076 * XXX Ideally we would wait only until the allocation could 3077 * be satisfied. This condition can cause new allocators to 3078 * consume all freed pages while old allocators wait. 3079 */ 3080 mtx_lock(&vm_domainset_lock); 3081 if (vm_page_count_min_set(&dset->ds_mask)) { 3082 vm_min_waiters++; 3083 msleep(&vm_min_domains, &vm_domainset_lock, PUSER | PDROP, 3084 "pfault", 0); 3085 } else 3086 mtx_unlock(&vm_domainset_lock); 3087 } 3088 3089 struct vm_pagequeue * 3090 vm_page_pagequeue(vm_page_t m) 3091 { 3092 3093 return (&vm_pagequeue_domain(m)->vmd_pagequeues[m->queue]); 3094 } 3095 3096 static struct mtx * 3097 vm_page_pagequeue_lockptr(vm_page_t m) 3098 { 3099 uint8_t queue; 3100 3101 if ((queue = atomic_load_8(&m->queue)) == PQ_NONE) 3102 return (NULL); 3103 return (&vm_pagequeue_domain(m)->vmd_pagequeues[queue].pq_mutex); 3104 } 3105 3106 static inline void 3107 vm_pqbatch_process_page(struct vm_pagequeue *pq, vm_page_t m) 3108 { 3109 struct vm_domain *vmd; 3110 uint8_t qflags; 3111 3112 CRITICAL_ASSERT(curthread); 3113 vm_pagequeue_assert_locked(pq); 3114 3115 /* 3116 * The page daemon is allowed to set m->queue = PQ_NONE without 3117 * the page queue lock held. In this case it is about to free the page, 3118 * which must not have any queue state. 3119 */ 3120 qflags = atomic_load_8(&m->aflags) & PGA_QUEUE_STATE_MASK; 3121 KASSERT(pq == vm_page_pagequeue(m) || qflags == 0, 3122 ("page %p doesn't belong to queue %p but has queue state %#x", 3123 m, pq, qflags)); 3124 3125 if ((qflags & PGA_DEQUEUE) != 0) { 3126 if (__predict_true((qflags & PGA_ENQUEUED) != 0)) { 3127 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 3128 vm_pagequeue_cnt_dec(pq); 3129 } 3130 vm_page_dequeue_complete(m); 3131 } else if ((qflags & (PGA_REQUEUE | PGA_REQUEUE_HEAD)) != 0) { 3132 if ((qflags & PGA_ENQUEUED) != 0) 3133 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 3134 else { 3135 vm_pagequeue_cnt_inc(pq); 3136 vm_page_aflag_set(m, PGA_ENQUEUED); 3137 } 3138 if ((qflags & PGA_REQUEUE_HEAD) != 0) { 3139 KASSERT(m->queue == PQ_INACTIVE, 3140 ("head enqueue not supported for page %p", m)); 3141 vmd = vm_pagequeue_domain(m); 3142 TAILQ_INSERT_BEFORE(&vmd->vmd_inacthead, m, plinks.q); 3143 } else 3144 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 3145 3146 /* 3147 * PGA_REQUEUE and PGA_REQUEUE_HEAD must be cleared after 3148 * setting PGA_ENQUEUED in order to synchronize with the 3149 * page daemon. 3150 */ 3151 vm_page_aflag_clear(m, PGA_REQUEUE | PGA_REQUEUE_HEAD); 3152 } 3153 } 3154 3155 static void 3156 vm_pqbatch_process(struct vm_pagequeue *pq, struct vm_batchqueue *bq, 3157 uint8_t queue) 3158 { 3159 vm_page_t m; 3160 int i; 3161 3162 for (i = 0; i < bq->bq_cnt; i++) { 3163 m = bq->bq_pa[i]; 3164 if (__predict_false(m->queue != queue)) 3165 continue; 3166 vm_pqbatch_process_page(pq, m); 3167 } 3168 vm_batchqueue_init(bq); 3169 } 3170 3171 static void 3172 vm_pqbatch_submit_page(vm_page_t m, uint8_t queue) 3173 { 3174 struct vm_batchqueue *bq; 3175 struct vm_pagequeue *pq; 3176 int domain; 3177 3178 vm_page_assert_locked(m); 3179 KASSERT(queue < PQ_COUNT, ("invalid queue %d", queue)); 3180 3181 domain = vm_phys_domain(m); 3182 pq = &vm_pagequeue_domain(m)->vmd_pagequeues[queue]; 3183 3184 critical_enter(); 3185 bq = DPCPU_PTR(pqbatch[domain][queue]); 3186 if (vm_batchqueue_insert(bq, m)) { 3187 critical_exit(); 3188 return; 3189 } 3190 if (!vm_pagequeue_trylock(pq)) { 3191 critical_exit(); 3192 vm_pagequeue_lock(pq); 3193 critical_enter(); 3194 bq = DPCPU_PTR(pqbatch[domain][queue]); 3195 } 3196 vm_pqbatch_process(pq, bq, queue); 3197 3198 /* 3199 * The page may have been logically dequeued before we acquired the 3200 * page queue lock. In this case, the page lock prevents the page 3201 * from being logically enqueued elsewhere. 3202 */ 3203 if (__predict_true(m->queue == queue)) 3204 vm_pqbatch_process_page(pq, m); 3205 else { 3206 KASSERT(m->queue == PQ_NONE, 3207 ("invalid queue transition for page %p", m)); 3208 KASSERT((m->aflags & PGA_ENQUEUED) == 0, 3209 ("page %p is enqueued with invalid queue index", m)); 3210 vm_page_aflag_clear(m, PGA_QUEUE_STATE_MASK); 3211 } 3212 vm_pagequeue_unlock(pq); 3213 critical_exit(); 3214 } 3215 3216 /* 3217 * vm_page_drain_pqbatch: [ internal use only ] 3218 * 3219 * Force all per-CPU page queue batch queues to be drained. This is 3220 * intended for use in severe memory shortages, to ensure that pages 3221 * do not remain stuck in the batch queues. 3222 */ 3223 void 3224 vm_page_drain_pqbatch(void) 3225 { 3226 struct thread *td; 3227 struct vm_domain *vmd; 3228 struct vm_pagequeue *pq; 3229 int cpu, domain, queue; 3230 3231 td = curthread; 3232 CPU_FOREACH(cpu) { 3233 thread_lock(td); 3234 sched_bind(td, cpu); 3235 thread_unlock(td); 3236 3237 for (domain = 0; domain < vm_ndomains; domain++) { 3238 vmd = VM_DOMAIN(domain); 3239 for (queue = 0; queue < PQ_COUNT; queue++) { 3240 pq = &vmd->vmd_pagequeues[queue]; 3241 vm_pagequeue_lock(pq); 3242 critical_enter(); 3243 vm_pqbatch_process(pq, 3244 DPCPU_PTR(pqbatch[domain][queue]), queue); 3245 critical_exit(); 3246 vm_pagequeue_unlock(pq); 3247 } 3248 } 3249 } 3250 thread_lock(td); 3251 sched_unbind(td); 3252 thread_unlock(td); 3253 } 3254 3255 /* 3256 * Complete the logical removal of a page from a page queue. We must be 3257 * careful to synchronize with the page daemon, which may be concurrently 3258 * examining the page with only the page lock held. The page must not be 3259 * in a state where it appears to be logically enqueued. 3260 */ 3261 static void 3262 vm_page_dequeue_complete(vm_page_t m) 3263 { 3264 3265 m->queue = PQ_NONE; 3266 atomic_thread_fence_rel(); 3267 vm_page_aflag_clear(m, PGA_QUEUE_STATE_MASK); 3268 } 3269 3270 /* 3271 * vm_page_dequeue_deferred: [ internal use only ] 3272 * 3273 * Request removal of the given page from its current page 3274 * queue. Physical removal from the queue may be deferred 3275 * indefinitely. 3276 * 3277 * The page must be locked. 3278 */ 3279 void 3280 vm_page_dequeue_deferred(vm_page_t m) 3281 { 3282 int queue; 3283 3284 vm_page_assert_locked(m); 3285 3286 queue = atomic_load_8(&m->queue); 3287 if (queue == PQ_NONE) { 3288 KASSERT((m->aflags & PGA_QUEUE_STATE_MASK) == 0, 3289 ("page %p has queue state", m)); 3290 return; 3291 } 3292 if ((m->aflags & PGA_DEQUEUE) == 0) 3293 vm_page_aflag_set(m, PGA_DEQUEUE); 3294 vm_pqbatch_submit_page(m, queue); 3295 } 3296 3297 /* 3298 * vm_page_dequeue: 3299 * 3300 * Remove the page from whichever page queue it's in, if any. 3301 * The page must either be locked or unallocated. This constraint 3302 * ensures that the queue state of the page will remain consistent 3303 * after this function returns. 3304 */ 3305 void 3306 vm_page_dequeue(vm_page_t m) 3307 { 3308 struct mtx *lock, *lock1; 3309 struct vm_pagequeue *pq; 3310 uint8_t aflags; 3311 3312 KASSERT(mtx_owned(vm_page_lockptr(m)) || m->order == VM_NFREEORDER, 3313 ("page %p is allocated and unlocked", m)); 3314 3315 for (;;) { 3316 lock = vm_page_pagequeue_lockptr(m); 3317 if (lock == NULL) { 3318 /* 3319 * A thread may be concurrently executing 3320 * vm_page_dequeue_complete(). Ensure that all queue 3321 * state is cleared before we return. 3322 */ 3323 aflags = atomic_load_8(&m->aflags); 3324 if ((aflags & PGA_QUEUE_STATE_MASK) == 0) 3325 return; 3326 KASSERT((aflags & PGA_DEQUEUE) != 0, 3327 ("page %p has unexpected queue state flags %#x", 3328 m, aflags)); 3329 3330 /* 3331 * Busy wait until the thread updating queue state is 3332 * finished. Such a thread must be executing in a 3333 * critical section. 3334 */ 3335 cpu_spinwait(); 3336 continue; 3337 } 3338 mtx_lock(lock); 3339 if ((lock1 = vm_page_pagequeue_lockptr(m)) == lock) 3340 break; 3341 mtx_unlock(lock); 3342 lock = lock1; 3343 } 3344 KASSERT(lock == vm_page_pagequeue_lockptr(m), 3345 ("%s: page %p migrated directly between queues", __func__, m)); 3346 KASSERT((m->aflags & PGA_DEQUEUE) != 0 || 3347 mtx_owned(vm_page_lockptr(m)), 3348 ("%s: queued unlocked page %p", __func__, m)); 3349 3350 if ((m->aflags & PGA_ENQUEUED) != 0) { 3351 pq = vm_page_pagequeue(m); 3352 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 3353 vm_pagequeue_cnt_dec(pq); 3354 } 3355 vm_page_dequeue_complete(m); 3356 mtx_unlock(lock); 3357 } 3358 3359 /* 3360 * Schedule the given page for insertion into the specified page queue. 3361 * Physical insertion of the page may be deferred indefinitely. 3362 */ 3363 static void 3364 vm_page_enqueue(vm_page_t m, uint8_t queue) 3365 { 3366 3367 vm_page_assert_locked(m); 3368 KASSERT(m->queue == PQ_NONE && (m->aflags & PGA_QUEUE_STATE_MASK) == 0, 3369 ("%s: page %p is already enqueued", __func__, m)); 3370 3371 m->queue = queue; 3372 if ((m->aflags & PGA_REQUEUE) == 0) 3373 vm_page_aflag_set(m, PGA_REQUEUE); 3374 vm_pqbatch_submit_page(m, queue); 3375 } 3376 3377 /* 3378 * vm_page_requeue: [ internal use only ] 3379 * 3380 * Schedule a requeue of the given page. 3381 * 3382 * The page must be locked. 3383 */ 3384 void 3385 vm_page_requeue(vm_page_t m) 3386 { 3387 3388 vm_page_assert_locked(m); 3389 KASSERT(m->queue != PQ_NONE, 3390 ("%s: page %p is not logically enqueued", __func__, m)); 3391 3392 if ((m->aflags & PGA_REQUEUE) == 0) 3393 vm_page_aflag_set(m, PGA_REQUEUE); 3394 vm_pqbatch_submit_page(m, atomic_load_8(&m->queue)); 3395 } 3396 3397 /* 3398 * vm_page_activate: 3399 * 3400 * Put the specified page on the active list (if appropriate). 3401 * Ensure that act_count is at least ACT_INIT but do not otherwise 3402 * mess with it. 3403 * 3404 * The page must be locked. 3405 */ 3406 void 3407 vm_page_activate(vm_page_t m) 3408 { 3409 3410 vm_page_assert_locked(m); 3411 3412 if (m->wire_count > 0 || (m->oflags & VPO_UNMANAGED) != 0) 3413 return; 3414 if (vm_page_queue(m) == PQ_ACTIVE) { 3415 if (m->act_count < ACT_INIT) 3416 m->act_count = ACT_INIT; 3417 return; 3418 } 3419 3420 vm_page_dequeue(m); 3421 if (m->act_count < ACT_INIT) 3422 m->act_count = ACT_INIT; 3423 vm_page_enqueue(m, PQ_ACTIVE); 3424 } 3425 3426 /* 3427 * vm_page_free_prep: 3428 * 3429 * Prepares the given page to be put on the free list, 3430 * disassociating it from any VM object. The caller may return 3431 * the page to the free list only if this function returns true. 3432 * 3433 * The object must be locked. The page must be locked if it is 3434 * managed. 3435 */ 3436 bool 3437 vm_page_free_prep(vm_page_t m) 3438 { 3439 3440 #if defined(DIAGNOSTIC) && defined(PHYS_TO_DMAP) 3441 if (PMAP_HAS_DMAP && (m->flags & PG_ZERO) != 0) { 3442 uint64_t *p; 3443 int i; 3444 p = (uint64_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m)); 3445 for (i = 0; i < PAGE_SIZE / sizeof(uint64_t); i++, p++) 3446 KASSERT(*p == 0, ("vm_page_free_prep %p PG_ZERO %d %jx", 3447 m, i, (uintmax_t)*p)); 3448 } 3449 #endif 3450 if ((m->oflags & VPO_UNMANAGED) == 0) { 3451 vm_page_lock_assert(m, MA_OWNED); 3452 KASSERT(!pmap_page_is_mapped(m), 3453 ("vm_page_free_prep: freeing mapped page %p", m)); 3454 } else 3455 KASSERT(m->queue == PQ_NONE, 3456 ("vm_page_free_prep: unmanaged page %p is queued", m)); 3457 VM_CNT_INC(v_tfree); 3458 3459 if (vm_page_sbusied(m)) 3460 panic("vm_page_free_prep: freeing busy page %p", m); 3461 3462 vm_page_remove(m); 3463 3464 /* 3465 * If fictitious remove object association and 3466 * return. 3467 */ 3468 if ((m->flags & PG_FICTITIOUS) != 0) { 3469 KASSERT(m->wire_count == 1, 3470 ("fictitious page %p is not wired", m)); 3471 KASSERT(m->queue == PQ_NONE, 3472 ("fictitious page %p is queued", m)); 3473 return (false); 3474 } 3475 3476 /* 3477 * Pages need not be dequeued before they are returned to the physical 3478 * memory allocator, but they must at least be marked for a deferred 3479 * dequeue. 3480 */ 3481 if ((m->oflags & VPO_UNMANAGED) == 0) 3482 vm_page_dequeue_deferred(m); 3483 3484 m->valid = 0; 3485 vm_page_undirty(m); 3486 3487 if (m->wire_count != 0) 3488 panic("vm_page_free_prep: freeing wired page %p", m); 3489 if (m->hold_count != 0) { 3490 m->flags &= ~PG_ZERO; 3491 KASSERT((m->flags & PG_UNHOLDFREE) == 0, 3492 ("vm_page_free_prep: freeing PG_UNHOLDFREE page %p", m)); 3493 m->flags |= PG_UNHOLDFREE; 3494 return (false); 3495 } 3496 3497 /* 3498 * Restore the default memory attribute to the page. 3499 */ 3500 if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT) 3501 pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT); 3502 3503 #if VM_NRESERVLEVEL > 0 3504 if (vm_reserv_free_page(m)) 3505 return (false); 3506 #endif 3507 3508 return (true); 3509 } 3510 3511 /* 3512 * vm_page_free_toq: 3513 * 3514 * Returns the given page to the free list, disassociating it 3515 * from any VM object. 3516 * 3517 * The object must be locked. The page must be locked if it is 3518 * managed. 3519 */ 3520 void 3521 vm_page_free_toq(vm_page_t m) 3522 { 3523 struct vm_domain *vmd; 3524 3525 if (!vm_page_free_prep(m)) 3526 return; 3527 3528 vmd = vm_pagequeue_domain(m); 3529 if (m->pool == VM_FREEPOOL_DEFAULT && vmd->vmd_pgcache != NULL) { 3530 uma_zfree(vmd->vmd_pgcache, m); 3531 return; 3532 } 3533 vm_domain_free_lock(vmd); 3534 vm_phys_free_pages(m, 0); 3535 vm_domain_free_unlock(vmd); 3536 vm_domain_freecnt_inc(vmd, 1); 3537 } 3538 3539 /* 3540 * vm_page_free_pages_toq: 3541 * 3542 * Returns a list of pages to the free list, disassociating it 3543 * from any VM object. In other words, this is equivalent to 3544 * calling vm_page_free_toq() for each page of a list of VM objects. 3545 * 3546 * The objects must be locked. The pages must be locked if it is 3547 * managed. 3548 */ 3549 void 3550 vm_page_free_pages_toq(struct spglist *free, bool update_wire_count) 3551 { 3552 vm_page_t m; 3553 int count; 3554 3555 if (SLIST_EMPTY(free)) 3556 return; 3557 3558 count = 0; 3559 while ((m = SLIST_FIRST(free)) != NULL) { 3560 count++; 3561 SLIST_REMOVE_HEAD(free, plinks.s.ss); 3562 vm_page_free_toq(m); 3563 } 3564 3565 if (update_wire_count) 3566 vm_wire_sub(count); 3567 } 3568 3569 /* 3570 * vm_page_wire: 3571 * 3572 * Mark this page as wired down. If the page is fictitious, then 3573 * its wire count must remain one. 3574 * 3575 * The page must be locked. 3576 */ 3577 void 3578 vm_page_wire(vm_page_t m) 3579 { 3580 3581 vm_page_assert_locked(m); 3582 if ((m->flags & PG_FICTITIOUS) != 0) { 3583 KASSERT(m->wire_count == 1, 3584 ("vm_page_wire: fictitious page %p's wire count isn't one", 3585 m)); 3586 return; 3587 } 3588 if (m->wire_count == 0) { 3589 KASSERT((m->oflags & VPO_UNMANAGED) == 0 || 3590 m->queue == PQ_NONE, 3591 ("vm_page_wire: unmanaged page %p is queued", m)); 3592 vm_wire_add(1); 3593 } 3594 m->wire_count++; 3595 KASSERT(m->wire_count != 0, ("vm_page_wire: wire_count overflow m=%p", m)); 3596 } 3597 3598 /* 3599 * vm_page_unwire: 3600 * 3601 * Release one wiring of the specified page, potentially allowing it to be 3602 * paged out. Returns TRUE if the number of wirings transitions to zero and 3603 * FALSE otherwise. 3604 * 3605 * Only managed pages belonging to an object can be paged out. If the number 3606 * of wirings transitions to zero and the page is eligible for page out, then 3607 * the page is added to the specified paging queue (unless PQ_NONE is 3608 * specified, in which case the page is dequeued if it belongs to a paging 3609 * queue). 3610 * 3611 * If a page is fictitious, then its wire count must always be one. 3612 * 3613 * A managed page must be locked. 3614 */ 3615 bool 3616 vm_page_unwire(vm_page_t m, uint8_t queue) 3617 { 3618 bool unwired; 3619 3620 KASSERT(queue < PQ_COUNT || queue == PQ_NONE, 3621 ("vm_page_unwire: invalid queue %u request for page %p", 3622 queue, m)); 3623 if ((m->oflags & VPO_UNMANAGED) == 0) 3624 vm_page_assert_locked(m); 3625 3626 unwired = vm_page_unwire_noq(m); 3627 if (!unwired || (m->oflags & VPO_UNMANAGED) != 0 || m->object == NULL) 3628 return (unwired); 3629 3630 if (vm_page_queue(m) == queue) { 3631 if (queue == PQ_ACTIVE) 3632 vm_page_reference(m); 3633 else if (queue != PQ_NONE) 3634 vm_page_requeue(m); 3635 } else { 3636 vm_page_dequeue(m); 3637 if (queue != PQ_NONE) { 3638 vm_page_enqueue(m, queue); 3639 if (queue == PQ_ACTIVE) 3640 /* Initialize act_count. */ 3641 vm_page_activate(m); 3642 } 3643 } 3644 return (unwired); 3645 } 3646 3647 /* 3648 * 3649 * vm_page_unwire_noq: 3650 * 3651 * Unwire a page without (re-)inserting it into a page queue. It is up 3652 * to the caller to enqueue, requeue, or free the page as appropriate. 3653 * In most cases, vm_page_unwire() should be used instead. 3654 */ 3655 bool 3656 vm_page_unwire_noq(vm_page_t m) 3657 { 3658 3659 if ((m->oflags & VPO_UNMANAGED) == 0) 3660 vm_page_assert_locked(m); 3661 if ((m->flags & PG_FICTITIOUS) != 0) { 3662 KASSERT(m->wire_count == 1, 3663 ("vm_page_unwire: fictitious page %p's wire count isn't one", m)); 3664 return (false); 3665 } 3666 if (m->wire_count == 0) 3667 panic("vm_page_unwire: page %p's wire count is zero", m); 3668 m->wire_count--; 3669 if (m->wire_count == 0) { 3670 vm_wire_sub(1); 3671 return (true); 3672 } else 3673 return (false); 3674 } 3675 3676 /* 3677 * Move the specified page to the tail of the inactive queue, or requeue 3678 * the page if it is already in the inactive queue. 3679 * 3680 * The page must be locked. 3681 */ 3682 void 3683 vm_page_deactivate(vm_page_t m) 3684 { 3685 3686 vm_page_assert_locked(m); 3687 3688 if (m->wire_count > 0 || (m->oflags & VPO_UNMANAGED) != 0) 3689 return; 3690 3691 if (!vm_page_inactive(m)) { 3692 vm_page_dequeue(m); 3693 vm_page_enqueue(m, PQ_INACTIVE); 3694 } else 3695 vm_page_requeue(m); 3696 } 3697 3698 /* 3699 * Move the specified page close to the head of the inactive queue, 3700 * bypassing LRU. A marker page is used to maintain FIFO ordering. 3701 * As with regular enqueues, we use a per-CPU batch queue to reduce 3702 * contention on the page queue lock. 3703 * 3704 * The page must be locked. 3705 */ 3706 void 3707 vm_page_deactivate_noreuse(vm_page_t m) 3708 { 3709 3710 vm_page_assert_locked(m); 3711 3712 if (m->wire_count > 0 || (m->oflags & VPO_UNMANAGED) != 0) 3713 return; 3714 3715 if (!vm_page_inactive(m)) { 3716 vm_page_dequeue(m); 3717 m->queue = PQ_INACTIVE; 3718 } 3719 if ((m->aflags & PGA_REQUEUE_HEAD) == 0) 3720 vm_page_aflag_set(m, PGA_REQUEUE_HEAD); 3721 vm_pqbatch_submit_page(m, PQ_INACTIVE); 3722 } 3723 3724 /* 3725 * vm_page_launder 3726 * 3727 * Put a page in the laundry, or requeue it if it is already there. 3728 */ 3729 void 3730 vm_page_launder(vm_page_t m) 3731 { 3732 3733 vm_page_assert_locked(m); 3734 if (m->wire_count > 0 || (m->oflags & VPO_UNMANAGED) != 0) 3735 return; 3736 3737 if (vm_page_in_laundry(m)) 3738 vm_page_requeue(m); 3739 else { 3740 vm_page_dequeue(m); 3741 vm_page_enqueue(m, PQ_LAUNDRY); 3742 } 3743 } 3744 3745 /* 3746 * vm_page_unswappable 3747 * 3748 * Put a page in the PQ_UNSWAPPABLE holding queue. 3749 */ 3750 void 3751 vm_page_unswappable(vm_page_t m) 3752 { 3753 3754 vm_page_assert_locked(m); 3755 KASSERT(m->wire_count == 0 && (m->oflags & VPO_UNMANAGED) == 0, 3756 ("page %p already unswappable", m)); 3757 3758 vm_page_dequeue(m); 3759 vm_page_enqueue(m, PQ_UNSWAPPABLE); 3760 } 3761 3762 /* 3763 * Attempt to free the page. If it cannot be freed, do nothing. Returns true 3764 * if the page is freed and false otherwise. 3765 * 3766 * The page must be managed. The page and its containing object must be 3767 * locked. 3768 */ 3769 bool 3770 vm_page_try_to_free(vm_page_t m) 3771 { 3772 3773 vm_page_assert_locked(m); 3774 VM_OBJECT_ASSERT_WLOCKED(m->object); 3775 KASSERT((m->oflags & VPO_UNMANAGED) == 0, ("page %p is unmanaged", m)); 3776 if (m->dirty != 0 || vm_page_held(m) || vm_page_busied(m)) 3777 return (false); 3778 if (m->object->ref_count != 0) { 3779 pmap_remove_all(m); 3780 if (m->dirty != 0) 3781 return (false); 3782 } 3783 vm_page_free(m); 3784 return (true); 3785 } 3786 3787 /* 3788 * vm_page_advise 3789 * 3790 * Apply the specified advice to the given page. 3791 * 3792 * The object and page must be locked. 3793 */ 3794 void 3795 vm_page_advise(vm_page_t m, int advice) 3796 { 3797 3798 vm_page_assert_locked(m); 3799 VM_OBJECT_ASSERT_WLOCKED(m->object); 3800 if (advice == MADV_FREE) 3801 /* 3802 * Mark the page clean. This will allow the page to be freed 3803 * without first paging it out. MADV_FREE pages are often 3804 * quickly reused by malloc(3), so we do not do anything that 3805 * would result in a page fault on a later access. 3806 */ 3807 vm_page_undirty(m); 3808 else if (advice != MADV_DONTNEED) { 3809 if (advice == MADV_WILLNEED) 3810 vm_page_activate(m); 3811 return; 3812 } 3813 3814 /* 3815 * Clear any references to the page. Otherwise, the page daemon will 3816 * immediately reactivate the page. 3817 */ 3818 vm_page_aflag_clear(m, PGA_REFERENCED); 3819 3820 if (advice != MADV_FREE && m->dirty == 0 && pmap_is_modified(m)) 3821 vm_page_dirty(m); 3822 3823 /* 3824 * Place clean pages near the head of the inactive queue rather than 3825 * the tail, thus defeating the queue's LRU operation and ensuring that 3826 * the page will be reused quickly. Dirty pages not already in the 3827 * laundry are moved there. 3828 */ 3829 if (m->dirty == 0) 3830 vm_page_deactivate_noreuse(m); 3831 else if (!vm_page_in_laundry(m)) 3832 vm_page_launder(m); 3833 } 3834 3835 /* 3836 * Grab a page, waiting until we are waken up due to the page 3837 * changing state. We keep on waiting, if the page continues 3838 * to be in the object. If the page doesn't exist, first allocate it 3839 * and then conditionally zero it. 3840 * 3841 * This routine may sleep. 3842 * 3843 * The object must be locked on entry. The lock will, however, be released 3844 * and reacquired if the routine sleeps. 3845 */ 3846 vm_page_t 3847 vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags) 3848 { 3849 vm_page_t m; 3850 int sleep; 3851 int pflags; 3852 3853 VM_OBJECT_ASSERT_WLOCKED(object); 3854 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || 3855 (allocflags & VM_ALLOC_IGN_SBUSY) != 0, 3856 ("vm_page_grab: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch")); 3857 pflags = allocflags & 3858 ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL); 3859 if ((allocflags & VM_ALLOC_NOWAIT) == 0) 3860 pflags |= VM_ALLOC_WAITFAIL; 3861 retrylookup: 3862 if ((m = vm_page_lookup(object, pindex)) != NULL) { 3863 sleep = (allocflags & VM_ALLOC_IGN_SBUSY) != 0 ? 3864 vm_page_xbusied(m) : vm_page_busied(m); 3865 if (sleep) { 3866 if ((allocflags & VM_ALLOC_NOWAIT) != 0) 3867 return (NULL); 3868 /* 3869 * Reference the page before unlocking and 3870 * sleeping so that the page daemon is less 3871 * likely to reclaim it. 3872 */ 3873 vm_page_aflag_set(m, PGA_REFERENCED); 3874 vm_page_lock(m); 3875 VM_OBJECT_WUNLOCK(object); 3876 vm_page_busy_sleep(m, "pgrbwt", (allocflags & 3877 VM_ALLOC_IGN_SBUSY) != 0); 3878 VM_OBJECT_WLOCK(object); 3879 goto retrylookup; 3880 } else { 3881 if ((allocflags & VM_ALLOC_WIRED) != 0) { 3882 vm_page_lock(m); 3883 vm_page_wire(m); 3884 vm_page_unlock(m); 3885 } 3886 if ((allocflags & 3887 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0) 3888 vm_page_xbusy(m); 3889 if ((allocflags & VM_ALLOC_SBUSY) != 0) 3890 vm_page_sbusy(m); 3891 return (m); 3892 } 3893 } 3894 m = vm_page_alloc(object, pindex, pflags); 3895 if (m == NULL) { 3896 if ((allocflags & VM_ALLOC_NOWAIT) != 0) 3897 return (NULL); 3898 goto retrylookup; 3899 } 3900 if (allocflags & VM_ALLOC_ZERO && (m->flags & PG_ZERO) == 0) 3901 pmap_zero_page(m); 3902 return (m); 3903 } 3904 3905 /* 3906 * Return the specified range of pages from the given object. For each 3907 * page offset within the range, if a page already exists within the object 3908 * at that offset and it is busy, then wait for it to change state. If, 3909 * instead, the page doesn't exist, then allocate it. 3910 * 3911 * The caller must always specify an allocation class. 3912 * 3913 * allocation classes: 3914 * VM_ALLOC_NORMAL normal process request 3915 * VM_ALLOC_SYSTEM system *really* needs the pages 3916 * 3917 * The caller must always specify that the pages are to be busied and/or 3918 * wired. 3919 * 3920 * optional allocation flags: 3921 * VM_ALLOC_IGN_SBUSY do not sleep on soft busy pages 3922 * VM_ALLOC_NOBUSY do not exclusive busy the page 3923 * VM_ALLOC_NOWAIT do not sleep 3924 * VM_ALLOC_SBUSY set page to sbusy state 3925 * VM_ALLOC_WIRED wire the pages 3926 * VM_ALLOC_ZERO zero and validate any invalid pages 3927 * 3928 * If VM_ALLOC_NOWAIT is not specified, this routine may sleep. Otherwise, it 3929 * may return a partial prefix of the requested range. 3930 */ 3931 int 3932 vm_page_grab_pages(vm_object_t object, vm_pindex_t pindex, int allocflags, 3933 vm_page_t *ma, int count) 3934 { 3935 vm_page_t m, mpred; 3936 int pflags; 3937 int i; 3938 bool sleep; 3939 3940 VM_OBJECT_ASSERT_WLOCKED(object); 3941 KASSERT(((u_int)allocflags >> VM_ALLOC_COUNT_SHIFT) == 0, 3942 ("vm_page_grap_pages: VM_ALLOC_COUNT() is not allowed")); 3943 KASSERT((allocflags & VM_ALLOC_NOBUSY) == 0 || 3944 (allocflags & VM_ALLOC_WIRED) != 0, 3945 ("vm_page_grab_pages: the pages must be busied or wired")); 3946 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || 3947 (allocflags & VM_ALLOC_IGN_SBUSY) != 0, 3948 ("vm_page_grab_pages: VM_ALLOC_SBUSY/IGN_SBUSY mismatch")); 3949 if (count == 0) 3950 return (0); 3951 pflags = allocflags & ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | 3952 VM_ALLOC_WAITFAIL | VM_ALLOC_IGN_SBUSY); 3953 if ((allocflags & VM_ALLOC_NOWAIT) == 0) 3954 pflags |= VM_ALLOC_WAITFAIL; 3955 i = 0; 3956 retrylookup: 3957 m = vm_radix_lookup_le(&object->rtree, pindex + i); 3958 if (m == NULL || m->pindex != pindex + i) { 3959 mpred = m; 3960 m = NULL; 3961 } else 3962 mpred = TAILQ_PREV(m, pglist, listq); 3963 for (; i < count; i++) { 3964 if (m != NULL) { 3965 sleep = (allocflags & VM_ALLOC_IGN_SBUSY) != 0 ? 3966 vm_page_xbusied(m) : vm_page_busied(m); 3967 if (sleep) { 3968 if ((allocflags & VM_ALLOC_NOWAIT) != 0) 3969 break; 3970 /* 3971 * Reference the page before unlocking and 3972 * sleeping so that the page daemon is less 3973 * likely to reclaim it. 3974 */ 3975 vm_page_aflag_set(m, PGA_REFERENCED); 3976 vm_page_lock(m); 3977 VM_OBJECT_WUNLOCK(object); 3978 vm_page_busy_sleep(m, "grbmaw", (allocflags & 3979 VM_ALLOC_IGN_SBUSY) != 0); 3980 VM_OBJECT_WLOCK(object); 3981 goto retrylookup; 3982 } 3983 if ((allocflags & VM_ALLOC_WIRED) != 0) { 3984 vm_page_lock(m); 3985 vm_page_wire(m); 3986 vm_page_unlock(m); 3987 } 3988 if ((allocflags & (VM_ALLOC_NOBUSY | 3989 VM_ALLOC_SBUSY)) == 0) 3990 vm_page_xbusy(m); 3991 if ((allocflags & VM_ALLOC_SBUSY) != 0) 3992 vm_page_sbusy(m); 3993 } else { 3994 m = vm_page_alloc_after(object, pindex + i, 3995 pflags | VM_ALLOC_COUNT(count - i), mpred); 3996 if (m == NULL) { 3997 if ((allocflags & VM_ALLOC_NOWAIT) != 0) 3998 break; 3999 goto retrylookup; 4000 } 4001 } 4002 if (m->valid == 0 && (allocflags & VM_ALLOC_ZERO) != 0) { 4003 if ((m->flags & PG_ZERO) == 0) 4004 pmap_zero_page(m); 4005 m->valid = VM_PAGE_BITS_ALL; 4006 } 4007 ma[i] = mpred = m; 4008 m = vm_page_next(m); 4009 } 4010 return (i); 4011 } 4012 4013 /* 4014 * Mapping function for valid or dirty bits in a page. 4015 * 4016 * Inputs are required to range within a page. 4017 */ 4018 vm_page_bits_t 4019 vm_page_bits(int base, int size) 4020 { 4021 int first_bit; 4022 int last_bit; 4023 4024 KASSERT( 4025 base + size <= PAGE_SIZE, 4026 ("vm_page_bits: illegal base/size %d/%d", base, size) 4027 ); 4028 4029 if (size == 0) /* handle degenerate case */ 4030 return (0); 4031 4032 first_bit = base >> DEV_BSHIFT; 4033 last_bit = (base + size - 1) >> DEV_BSHIFT; 4034 4035 return (((vm_page_bits_t)2 << last_bit) - 4036 ((vm_page_bits_t)1 << first_bit)); 4037 } 4038 4039 /* 4040 * vm_page_set_valid_range: 4041 * 4042 * Sets portions of a page valid. The arguments are expected 4043 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive 4044 * of any partial chunks touched by the range. The invalid portion of 4045 * such chunks will be zeroed. 4046 * 4047 * (base + size) must be less then or equal to PAGE_SIZE. 4048 */ 4049 void 4050 vm_page_set_valid_range(vm_page_t m, int base, int size) 4051 { 4052 int endoff, frag; 4053 4054 VM_OBJECT_ASSERT_WLOCKED(m->object); 4055 if (size == 0) /* handle degenerate case */ 4056 return; 4057 4058 /* 4059 * If the base is not DEV_BSIZE aligned and the valid 4060 * bit is clear, we have to zero out a portion of the 4061 * first block. 4062 */ 4063 if ((frag = rounddown2(base, DEV_BSIZE)) != base && 4064 (m->valid & (1 << (base >> DEV_BSHIFT))) == 0) 4065 pmap_zero_page_area(m, frag, base - frag); 4066 4067 /* 4068 * If the ending offset is not DEV_BSIZE aligned and the 4069 * valid bit is clear, we have to zero out a portion of 4070 * the last block. 4071 */ 4072 endoff = base + size; 4073 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && 4074 (m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0) 4075 pmap_zero_page_area(m, endoff, 4076 DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); 4077 4078 /* 4079 * Assert that no previously invalid block that is now being validated 4080 * is already dirty. 4081 */ 4082 KASSERT((~m->valid & vm_page_bits(base, size) & m->dirty) == 0, 4083 ("vm_page_set_valid_range: page %p is dirty", m)); 4084 4085 /* 4086 * Set valid bits inclusive of any overlap. 4087 */ 4088 m->valid |= vm_page_bits(base, size); 4089 } 4090 4091 /* 4092 * Clear the given bits from the specified page's dirty field. 4093 */ 4094 static __inline void 4095 vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits) 4096 { 4097 uintptr_t addr; 4098 #if PAGE_SIZE < 16384 4099 int shift; 4100 #endif 4101 4102 /* 4103 * If the object is locked and the page is neither exclusive busy nor 4104 * write mapped, then the page's dirty field cannot possibly be 4105 * set by a concurrent pmap operation. 4106 */ 4107 VM_OBJECT_ASSERT_WLOCKED(m->object); 4108 if (!vm_page_xbusied(m) && !pmap_page_is_write_mapped(m)) 4109 m->dirty &= ~pagebits; 4110 else { 4111 /* 4112 * The pmap layer can call vm_page_dirty() without 4113 * holding a distinguished lock. The combination of 4114 * the object's lock and an atomic operation suffice 4115 * to guarantee consistency of the page dirty field. 4116 * 4117 * For PAGE_SIZE == 32768 case, compiler already 4118 * properly aligns the dirty field, so no forcible 4119 * alignment is needed. Only require existence of 4120 * atomic_clear_64 when page size is 32768. 4121 */ 4122 addr = (uintptr_t)&m->dirty; 4123 #if PAGE_SIZE == 32768 4124 atomic_clear_64((uint64_t *)addr, pagebits); 4125 #elif PAGE_SIZE == 16384 4126 atomic_clear_32((uint32_t *)addr, pagebits); 4127 #else /* PAGE_SIZE <= 8192 */ 4128 /* 4129 * Use a trick to perform a 32-bit atomic on the 4130 * containing aligned word, to not depend on the existence 4131 * of atomic_clear_{8, 16}. 4132 */ 4133 shift = addr & (sizeof(uint32_t) - 1); 4134 #if BYTE_ORDER == BIG_ENDIAN 4135 shift = (sizeof(uint32_t) - sizeof(m->dirty) - shift) * NBBY; 4136 #else 4137 shift *= NBBY; 4138 #endif 4139 addr &= ~(sizeof(uint32_t) - 1); 4140 atomic_clear_32((uint32_t *)addr, pagebits << shift); 4141 #endif /* PAGE_SIZE */ 4142 } 4143 } 4144 4145 /* 4146 * vm_page_set_validclean: 4147 * 4148 * Sets portions of a page valid and clean. The arguments are expected 4149 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive 4150 * of any partial chunks touched by the range. The invalid portion of 4151 * such chunks will be zero'd. 4152 * 4153 * (base + size) must be less then or equal to PAGE_SIZE. 4154 */ 4155 void 4156 vm_page_set_validclean(vm_page_t m, int base, int size) 4157 { 4158 vm_page_bits_t oldvalid, pagebits; 4159 int endoff, frag; 4160 4161 VM_OBJECT_ASSERT_WLOCKED(m->object); 4162 if (size == 0) /* handle degenerate case */ 4163 return; 4164 4165 /* 4166 * If the base is not DEV_BSIZE aligned and the valid 4167 * bit is clear, we have to zero out a portion of the 4168 * first block. 4169 */ 4170 if ((frag = rounddown2(base, DEV_BSIZE)) != base && 4171 (m->valid & ((vm_page_bits_t)1 << (base >> DEV_BSHIFT))) == 0) 4172 pmap_zero_page_area(m, frag, base - frag); 4173 4174 /* 4175 * If the ending offset is not DEV_BSIZE aligned and the 4176 * valid bit is clear, we have to zero out a portion of 4177 * the last block. 4178 */ 4179 endoff = base + size; 4180 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && 4181 (m->valid & ((vm_page_bits_t)1 << (endoff >> DEV_BSHIFT))) == 0) 4182 pmap_zero_page_area(m, endoff, 4183 DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); 4184 4185 /* 4186 * Set valid, clear dirty bits. If validating the entire 4187 * page we can safely clear the pmap modify bit. We also 4188 * use this opportunity to clear the VPO_NOSYNC flag. If a process 4189 * takes a write fault on a MAP_NOSYNC memory area the flag will 4190 * be set again. 4191 * 4192 * We set valid bits inclusive of any overlap, but we can only 4193 * clear dirty bits for DEV_BSIZE chunks that are fully within 4194 * the range. 4195 */ 4196 oldvalid = m->valid; 4197 pagebits = vm_page_bits(base, size); 4198 m->valid |= pagebits; 4199 #if 0 /* NOT YET */ 4200 if ((frag = base & (DEV_BSIZE - 1)) != 0) { 4201 frag = DEV_BSIZE - frag; 4202 base += frag; 4203 size -= frag; 4204 if (size < 0) 4205 size = 0; 4206 } 4207 pagebits = vm_page_bits(base, size & (DEV_BSIZE - 1)); 4208 #endif 4209 if (base == 0 && size == PAGE_SIZE) { 4210 /* 4211 * The page can only be modified within the pmap if it is 4212 * mapped, and it can only be mapped if it was previously 4213 * fully valid. 4214 */ 4215 if (oldvalid == VM_PAGE_BITS_ALL) 4216 /* 4217 * Perform the pmap_clear_modify() first. Otherwise, 4218 * a concurrent pmap operation, such as 4219 * pmap_protect(), could clear a modification in the 4220 * pmap and set the dirty field on the page before 4221 * pmap_clear_modify() had begun and after the dirty 4222 * field was cleared here. 4223 */ 4224 pmap_clear_modify(m); 4225 m->dirty = 0; 4226 m->oflags &= ~VPO_NOSYNC; 4227 } else if (oldvalid != VM_PAGE_BITS_ALL) 4228 m->dirty &= ~pagebits; 4229 else 4230 vm_page_clear_dirty_mask(m, pagebits); 4231 } 4232 4233 void 4234 vm_page_clear_dirty(vm_page_t m, int base, int size) 4235 { 4236 4237 vm_page_clear_dirty_mask(m, vm_page_bits(base, size)); 4238 } 4239 4240 /* 4241 * vm_page_set_invalid: 4242 * 4243 * Invalidates DEV_BSIZE'd chunks within a page. Both the 4244 * valid and dirty bits for the effected areas are cleared. 4245 */ 4246 void 4247 vm_page_set_invalid(vm_page_t m, int base, int size) 4248 { 4249 vm_page_bits_t bits; 4250 vm_object_t object; 4251 4252 object = m->object; 4253 VM_OBJECT_ASSERT_WLOCKED(object); 4254 if (object->type == OBJT_VNODE && base == 0 && IDX_TO_OFF(m->pindex) + 4255 size >= object->un_pager.vnp.vnp_size) 4256 bits = VM_PAGE_BITS_ALL; 4257 else 4258 bits = vm_page_bits(base, size); 4259 if (object->ref_count != 0 && m->valid == VM_PAGE_BITS_ALL && 4260 bits != 0) 4261 pmap_remove_all(m); 4262 KASSERT((bits == 0 && m->valid == VM_PAGE_BITS_ALL) || 4263 !pmap_page_is_mapped(m), 4264 ("vm_page_set_invalid: page %p is mapped", m)); 4265 m->valid &= ~bits; 4266 m->dirty &= ~bits; 4267 } 4268 4269 /* 4270 * vm_page_zero_invalid() 4271 * 4272 * The kernel assumes that the invalid portions of a page contain 4273 * garbage, but such pages can be mapped into memory by user code. 4274 * When this occurs, we must zero out the non-valid portions of the 4275 * page so user code sees what it expects. 4276 * 4277 * Pages are most often semi-valid when the end of a file is mapped 4278 * into memory and the file's size is not page aligned. 4279 */ 4280 void 4281 vm_page_zero_invalid(vm_page_t m, boolean_t setvalid) 4282 { 4283 int b; 4284 int i; 4285 4286 VM_OBJECT_ASSERT_WLOCKED(m->object); 4287 /* 4288 * Scan the valid bits looking for invalid sections that 4289 * must be zeroed. Invalid sub-DEV_BSIZE'd areas ( where the 4290 * valid bit may be set ) have already been zeroed by 4291 * vm_page_set_validclean(). 4292 */ 4293 for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) { 4294 if (i == (PAGE_SIZE / DEV_BSIZE) || 4295 (m->valid & ((vm_page_bits_t)1 << i))) { 4296 if (i > b) { 4297 pmap_zero_page_area(m, 4298 b << DEV_BSHIFT, (i - b) << DEV_BSHIFT); 4299 } 4300 b = i + 1; 4301 } 4302 } 4303 4304 /* 4305 * setvalid is TRUE when we can safely set the zero'd areas 4306 * as being valid. We can do this if there are no cache consistancy 4307 * issues. e.g. it is ok to do with UFS, but not ok to do with NFS. 4308 */ 4309 if (setvalid) 4310 m->valid = VM_PAGE_BITS_ALL; 4311 } 4312 4313 /* 4314 * vm_page_is_valid: 4315 * 4316 * Is (partial) page valid? Note that the case where size == 0 4317 * will return FALSE in the degenerate case where the page is 4318 * entirely invalid, and TRUE otherwise. 4319 */ 4320 int 4321 vm_page_is_valid(vm_page_t m, int base, int size) 4322 { 4323 vm_page_bits_t bits; 4324 4325 VM_OBJECT_ASSERT_LOCKED(m->object); 4326 bits = vm_page_bits(base, size); 4327 return (m->valid != 0 && (m->valid & bits) == bits); 4328 } 4329 4330 /* 4331 * Returns true if all of the specified predicates are true for the entire 4332 * (super)page and false otherwise. 4333 */ 4334 bool 4335 vm_page_ps_test(vm_page_t m, int flags, vm_page_t skip_m) 4336 { 4337 vm_object_t object; 4338 int i, npages; 4339 4340 object = m->object; 4341 if (skip_m != NULL && skip_m->object != object) 4342 return (false); 4343 VM_OBJECT_ASSERT_LOCKED(object); 4344 npages = atop(pagesizes[m->psind]); 4345 4346 /* 4347 * The physically contiguous pages that make up a superpage, i.e., a 4348 * page with a page size index ("psind") greater than zero, will 4349 * occupy adjacent entries in vm_page_array[]. 4350 */ 4351 for (i = 0; i < npages; i++) { 4352 /* Always test object consistency, including "skip_m". */ 4353 if (m[i].object != object) 4354 return (false); 4355 if (&m[i] == skip_m) 4356 continue; 4357 if ((flags & PS_NONE_BUSY) != 0 && vm_page_busied(&m[i])) 4358 return (false); 4359 if ((flags & PS_ALL_DIRTY) != 0) { 4360 /* 4361 * Calling vm_page_test_dirty() or pmap_is_modified() 4362 * might stop this case from spuriously returning 4363 * "false". However, that would require a write lock 4364 * on the object containing "m[i]". 4365 */ 4366 if (m[i].dirty != VM_PAGE_BITS_ALL) 4367 return (false); 4368 } 4369 if ((flags & PS_ALL_VALID) != 0 && 4370 m[i].valid != VM_PAGE_BITS_ALL) 4371 return (false); 4372 } 4373 return (true); 4374 } 4375 4376 /* 4377 * Set the page's dirty bits if the page is modified. 4378 */ 4379 void 4380 vm_page_test_dirty(vm_page_t m) 4381 { 4382 4383 VM_OBJECT_ASSERT_WLOCKED(m->object); 4384 if (m->dirty != VM_PAGE_BITS_ALL && pmap_is_modified(m)) 4385 vm_page_dirty(m); 4386 } 4387 4388 void 4389 vm_page_lock_KBI(vm_page_t m, const char *file, int line) 4390 { 4391 4392 mtx_lock_flags_(vm_page_lockptr(m), 0, file, line); 4393 } 4394 4395 void 4396 vm_page_unlock_KBI(vm_page_t m, const char *file, int line) 4397 { 4398 4399 mtx_unlock_flags_(vm_page_lockptr(m), 0, file, line); 4400 } 4401 4402 int 4403 vm_page_trylock_KBI(vm_page_t m, const char *file, int line) 4404 { 4405 4406 return (mtx_trylock_flags_(vm_page_lockptr(m), 0, file, line)); 4407 } 4408 4409 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT) 4410 void 4411 vm_page_assert_locked_KBI(vm_page_t m, const char *file, int line) 4412 { 4413 4414 vm_page_lock_assert_KBI(m, MA_OWNED, file, line); 4415 } 4416 4417 void 4418 vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line) 4419 { 4420 4421 mtx_assert_(vm_page_lockptr(m), a, file, line); 4422 } 4423 #endif 4424 4425 #ifdef INVARIANTS 4426 void 4427 vm_page_object_lock_assert(vm_page_t m) 4428 { 4429 4430 /* 4431 * Certain of the page's fields may only be modified by the 4432 * holder of the containing object's lock or the exclusive busy. 4433 * holder. Unfortunately, the holder of the write busy is 4434 * not recorded, and thus cannot be checked here. 4435 */ 4436 if (m->object != NULL && !vm_page_xbusied(m)) 4437 VM_OBJECT_ASSERT_WLOCKED(m->object); 4438 } 4439 4440 void 4441 vm_page_assert_pga_writeable(vm_page_t m, uint8_t bits) 4442 { 4443 4444 if ((bits & PGA_WRITEABLE) == 0) 4445 return; 4446 4447 /* 4448 * The PGA_WRITEABLE flag can only be set if the page is 4449 * managed, is exclusively busied or the object is locked. 4450 * Currently, this flag is only set by pmap_enter(). 4451 */ 4452 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 4453 ("PGA_WRITEABLE on unmanaged page")); 4454 if (!vm_page_xbusied(m)) 4455 VM_OBJECT_ASSERT_LOCKED(m->object); 4456 } 4457 #endif 4458 4459 #include "opt_ddb.h" 4460 #ifdef DDB 4461 #include <sys/kernel.h> 4462 4463 #include <ddb/ddb.h> 4464 4465 DB_SHOW_COMMAND(page, vm_page_print_page_info) 4466 { 4467 4468 db_printf("vm_cnt.v_free_count: %d\n", vm_free_count()); 4469 db_printf("vm_cnt.v_inactive_count: %d\n", vm_inactive_count()); 4470 db_printf("vm_cnt.v_active_count: %d\n", vm_active_count()); 4471 db_printf("vm_cnt.v_laundry_count: %d\n", vm_laundry_count()); 4472 db_printf("vm_cnt.v_wire_count: %d\n", vm_wire_count()); 4473 db_printf("vm_cnt.v_free_reserved: %d\n", vm_cnt.v_free_reserved); 4474 db_printf("vm_cnt.v_free_min: %d\n", vm_cnt.v_free_min); 4475 db_printf("vm_cnt.v_free_target: %d\n", vm_cnt.v_free_target); 4476 db_printf("vm_cnt.v_inactive_target: %d\n", vm_cnt.v_inactive_target); 4477 } 4478 4479 DB_SHOW_COMMAND(pageq, vm_page_print_pageq_info) 4480 { 4481 int dom; 4482 4483 db_printf("pq_free %d\n", vm_free_count()); 4484 for (dom = 0; dom < vm_ndomains; dom++) { 4485 db_printf( 4486 "dom %d page_cnt %d free %d pq_act %d pq_inact %d pq_laund %d pq_unsw %d\n", 4487 dom, 4488 vm_dom[dom].vmd_page_count, 4489 vm_dom[dom].vmd_free_count, 4490 vm_dom[dom].vmd_pagequeues[PQ_ACTIVE].pq_cnt, 4491 vm_dom[dom].vmd_pagequeues[PQ_INACTIVE].pq_cnt, 4492 vm_dom[dom].vmd_pagequeues[PQ_LAUNDRY].pq_cnt, 4493 vm_dom[dom].vmd_pagequeues[PQ_UNSWAPPABLE].pq_cnt); 4494 } 4495 } 4496 4497 DB_SHOW_COMMAND(pginfo, vm_page_print_pginfo) 4498 { 4499 vm_page_t m; 4500 boolean_t phys, virt; 4501 4502 if (!have_addr) { 4503 db_printf("show pginfo addr\n"); 4504 return; 4505 } 4506 4507 phys = strchr(modif, 'p') != NULL; 4508 virt = strchr(modif, 'v') != NULL; 4509 if (virt) 4510 m = PHYS_TO_VM_PAGE(pmap_kextract(addr)); 4511 else if (phys) 4512 m = PHYS_TO_VM_PAGE(addr); 4513 else 4514 m = (vm_page_t)addr; 4515 db_printf( 4516 "page %p obj %p pidx 0x%jx phys 0x%jx q %d hold %d wire %d\n" 4517 " af 0x%x of 0x%x f 0x%x act %d busy %x valid 0x%x dirty 0x%x\n", 4518 m, m->object, (uintmax_t)m->pindex, (uintmax_t)m->phys_addr, 4519 m->queue, m->hold_count, m->wire_count, m->aflags, m->oflags, 4520 m->flags, m->act_count, m->busy_lock, m->valid, m->dirty); 4521 } 4522 #endif /* DDB */ 4523