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 36 /*- 37 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 38 * All rights reserved. 39 * 40 * Authors: Avadis Tevanian, Jr., Michael Wayne Young 41 * 42 * Permission to use, copy, modify and distribute this software and 43 * its documentation is hereby granted, provided that both the copyright 44 * notice and this permission notice appear in all copies of the 45 * software, derivative works or modified versions, and any portions 46 * thereof, and that both notices appear in supporting documentation. 47 * 48 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 49 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 50 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 51 * 52 * Carnegie Mellon requests users of this software to return to 53 * 54 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 55 * School of Computer Science 56 * Carnegie Mellon University 57 * Pittsburgh PA 15213-3890 58 * 59 * any improvements or extensions that they make and grant Carnegie the 60 * rights to redistribute these changes. 61 */ 62 63 /* 64 * Resident memory management module. 65 */ 66 67 #include <sys/cdefs.h> 68 #include "opt_vm.h" 69 70 #include <sys/param.h> 71 #include <sys/systm.h> 72 #include <sys/counter.h> 73 #include <sys/domainset.h> 74 #include <sys/kernel.h> 75 #include <sys/limits.h> 76 #include <sys/linker.h> 77 #include <sys/lock.h> 78 #include <sys/malloc.h> 79 #include <sys/mman.h> 80 #include <sys/msgbuf.h> 81 #include <sys/mutex.h> 82 #include <sys/proc.h> 83 #include <sys/rwlock.h> 84 #include <sys/sleepqueue.h> 85 #include <sys/sbuf.h> 86 #include <sys/sched.h> 87 #include <sys/smp.h> 88 #include <sys/sysctl.h> 89 #include <sys/vmmeter.h> 90 #include <sys/vnode.h> 91 92 #include <vm/vm.h> 93 #include <vm/pmap.h> 94 #include <vm/vm_param.h> 95 #include <vm/vm_domainset.h> 96 #include <vm/vm_kern.h> 97 #include <vm/vm_map.h> 98 #include <vm/vm_object.h> 99 #include <vm/vm_page.h> 100 #include <vm/vm_pageout.h> 101 #include <vm/vm_phys.h> 102 #include <vm/vm_pagequeue.h> 103 #include <vm/vm_pager.h> 104 #include <vm/vm_radix.h> 105 #include <vm/vm_reserv.h> 106 #include <vm/vm_extern.h> 107 #include <vm/vm_dumpset.h> 108 #include <vm/uma.h> 109 #include <vm/uma_int.h> 110 111 #include <machine/md_var.h> 112 113 struct vm_domain vm_dom[MAXMEMDOM]; 114 115 DPCPU_DEFINE_STATIC(struct vm_batchqueue, pqbatch[MAXMEMDOM][PQ_COUNT]); 116 117 struct mtx_padalign __exclusive_cache_line pa_lock[PA_LOCK_COUNT]; 118 119 struct mtx_padalign __exclusive_cache_line vm_domainset_lock; 120 /* The following fields are protected by the domainset lock. */ 121 domainset_t __exclusive_cache_line vm_min_domains; 122 domainset_t __exclusive_cache_line vm_severe_domains; 123 static int vm_min_waiters; 124 static int vm_severe_waiters; 125 static int vm_pageproc_waiters; 126 127 static SYSCTL_NODE(_vm_stats, OID_AUTO, page, CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 128 "VM page statistics"); 129 130 static COUNTER_U64_DEFINE_EARLY(pqstate_commit_retries); 131 SYSCTL_COUNTER_U64(_vm_stats_page, OID_AUTO, pqstate_commit_retries, 132 CTLFLAG_RD, &pqstate_commit_retries, 133 "Number of failed per-page atomic queue state updates"); 134 135 static COUNTER_U64_DEFINE_EARLY(queue_ops); 136 SYSCTL_COUNTER_U64(_vm_stats_page, OID_AUTO, queue_ops, 137 CTLFLAG_RD, &queue_ops, 138 "Number of batched queue operations"); 139 140 static COUNTER_U64_DEFINE_EARLY(queue_nops); 141 SYSCTL_COUNTER_U64(_vm_stats_page, OID_AUTO, queue_nops, 142 CTLFLAG_RD, &queue_nops, 143 "Number of batched queue operations with no effects"); 144 145 /* 146 * bogus page -- for I/O to/from partially complete buffers, 147 * or for paging into sparsely invalid regions. 148 */ 149 vm_page_t bogus_page; 150 151 vm_page_t vm_page_array; 152 long vm_page_array_size; 153 long first_page; 154 155 struct bitset *vm_page_dump; 156 long vm_page_dump_pages; 157 158 static TAILQ_HEAD(, vm_page) blacklist_head; 159 static int sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS); 160 SYSCTL_PROC(_vm, OID_AUTO, page_blacklist, CTLTYPE_STRING | CTLFLAG_RD | 161 CTLFLAG_MPSAFE, NULL, 0, sysctl_vm_page_blacklist, "A", "Blacklist pages"); 162 163 static uma_zone_t fakepg_zone; 164 165 static vm_page_t vm_page_alloc_after(vm_object_t object, vm_pindex_t pindex, 166 int req, vm_page_t mpred); 167 static void vm_page_alloc_check(vm_page_t m); 168 static vm_page_t vm_page_alloc_nofree_domain(int domain, int req); 169 static bool _vm_page_busy_sleep(vm_object_t obj, vm_page_t m, 170 vm_pindex_t pindex, const char *wmesg, int allocflags, bool locked); 171 static void vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits); 172 static void vm_page_enqueue(vm_page_t m, uint8_t queue); 173 static bool vm_page_free_prep(vm_page_t m); 174 static void vm_page_free_toq(vm_page_t m); 175 static void vm_page_init(void *dummy); 176 static int vm_page_insert_after(vm_page_t m, vm_object_t object, 177 vm_pindex_t pindex, vm_page_t mpred); 178 static void vm_page_insert_radixdone(vm_page_t m, vm_object_t object, 179 vm_page_t mpred); 180 static void vm_page_mvqueue(vm_page_t m, const uint8_t queue, 181 const uint16_t nflag); 182 static int vm_page_reclaim_run(int req_class, int domain, u_long npages, 183 vm_page_t m_run, vm_paddr_t high); 184 static void vm_page_release_toq(vm_page_t m, uint8_t nqueue, bool noreuse); 185 static int vm_domain_alloc_fail(struct vm_domain *vmd, vm_object_t object, 186 int req); 187 static int vm_page_zone_import(void *arg, void **store, int cnt, int domain, 188 int flags); 189 static void vm_page_zone_release(void *arg, void **store, int cnt); 190 191 SYSINIT(vm_page, SI_SUB_VM, SI_ORDER_SECOND, vm_page_init, NULL); 192 193 static void 194 vm_page_init(void *dummy) 195 { 196 197 fakepg_zone = uma_zcreate("fakepg", sizeof(struct vm_page), NULL, NULL, 198 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 199 bogus_page = vm_page_alloc_noobj(VM_ALLOC_WIRED | VM_ALLOC_NOFREE); 200 } 201 202 static int pgcache_zone_max_pcpu; 203 SYSCTL_INT(_vm, OID_AUTO, pgcache_zone_max_pcpu, 204 CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &pgcache_zone_max_pcpu, 0, 205 "Per-CPU page cache size"); 206 207 /* 208 * The cache page zone is initialized later since we need to be able to allocate 209 * pages before UMA is fully initialized. 210 */ 211 static void 212 vm_page_init_cache_zones(void *dummy __unused) 213 { 214 struct vm_domain *vmd; 215 struct vm_pgcache *pgcache; 216 int cache, domain, maxcache, pool; 217 218 TUNABLE_INT_FETCH("vm.pgcache_zone_max_pcpu", &pgcache_zone_max_pcpu); 219 maxcache = pgcache_zone_max_pcpu * mp_ncpus; 220 for (domain = 0; domain < vm_ndomains; domain++) { 221 vmd = VM_DOMAIN(domain); 222 for (pool = 0; pool < VM_NFREEPOOL; pool++) { 223 pgcache = &vmd->vmd_pgcache[pool]; 224 pgcache->domain = domain; 225 pgcache->pool = pool; 226 pgcache->zone = uma_zcache_create("vm pgcache", 227 PAGE_SIZE, NULL, NULL, NULL, NULL, 228 vm_page_zone_import, vm_page_zone_release, pgcache, 229 UMA_ZONE_VM); 230 231 /* 232 * Limit each pool's zone to 0.1% of the pages in the 233 * domain. 234 */ 235 cache = maxcache != 0 ? maxcache : 236 vmd->vmd_page_count / 1000; 237 uma_zone_set_maxcache(pgcache->zone, cache); 238 } 239 } 240 } 241 SYSINIT(vm_page2, SI_SUB_VM_CONF, SI_ORDER_ANY, vm_page_init_cache_zones, NULL); 242 243 /* Make sure that u_long is at least 64 bits when PAGE_SIZE is 32K. */ 244 #if PAGE_SIZE == 32768 245 #ifdef CTASSERT 246 CTASSERT(sizeof(u_long) >= 8); 247 #endif 248 #endif 249 250 /* 251 * vm_set_page_size: 252 * 253 * Sets the page size, perhaps based upon the memory 254 * size. Must be called before any use of page-size 255 * dependent functions. 256 */ 257 void 258 vm_set_page_size(void) 259 { 260 if (vm_cnt.v_page_size == 0) 261 vm_cnt.v_page_size = PAGE_SIZE; 262 if (((vm_cnt.v_page_size - 1) & vm_cnt.v_page_size) != 0) 263 panic("vm_set_page_size: page size not a power of two"); 264 } 265 266 /* 267 * vm_page_blacklist_next: 268 * 269 * Find the next entry in the provided string of blacklist 270 * addresses. Entries are separated by space, comma, or newline. 271 * If an invalid integer is encountered then the rest of the 272 * string is skipped. Updates the list pointer to the next 273 * character, or NULL if the string is exhausted or invalid. 274 */ 275 static vm_paddr_t 276 vm_page_blacklist_next(char **list, char *end) 277 { 278 vm_paddr_t bad; 279 char *cp, *pos; 280 281 if (list == NULL || *list == NULL) 282 return (0); 283 if (**list =='\0') { 284 *list = NULL; 285 return (0); 286 } 287 288 /* 289 * If there's no end pointer then the buffer is coming from 290 * the kenv and we know it's null-terminated. 291 */ 292 if (end == NULL) 293 end = *list + strlen(*list); 294 295 /* Ensure that strtoq() won't walk off the end */ 296 if (*end != '\0') { 297 if (*end == '\n' || *end == ' ' || *end == ',') 298 *end = '\0'; 299 else { 300 printf("Blacklist not terminated, skipping\n"); 301 *list = NULL; 302 return (0); 303 } 304 } 305 306 for (pos = *list; *pos != '\0'; pos = cp) { 307 bad = strtoq(pos, &cp, 0); 308 if (*cp == '\0' || *cp == ' ' || *cp == ',' || *cp == '\n') { 309 if (bad == 0) { 310 if (++cp < end) 311 continue; 312 else 313 break; 314 } 315 } else 316 break; 317 if (*cp == '\0' || ++cp >= end) 318 *list = NULL; 319 else 320 *list = cp; 321 return (trunc_page(bad)); 322 } 323 printf("Garbage in RAM blacklist, skipping\n"); 324 *list = NULL; 325 return (0); 326 } 327 328 bool 329 vm_page_blacklist_add(vm_paddr_t pa, bool verbose) 330 { 331 struct vm_domain *vmd; 332 vm_page_t m; 333 bool found; 334 335 m = vm_phys_paddr_to_vm_page(pa); 336 if (m == NULL) 337 return (true); /* page does not exist, no failure */ 338 339 vmd = VM_DOMAIN(vm_phys_domain(pa)); 340 vm_domain_free_lock(vmd); 341 found = vm_phys_unfree_page(pa); 342 vm_domain_free_unlock(vmd); 343 if (found) { 344 vm_domain_freecnt_inc(vmd, -1); 345 TAILQ_INSERT_TAIL(&blacklist_head, m, listq); 346 if (verbose) 347 printf("Skipping page with pa 0x%jx\n", (uintmax_t)pa); 348 } 349 return (found); 350 } 351 352 /* 353 * vm_page_blacklist_check: 354 * 355 * Iterate through the provided string of blacklist addresses, pulling 356 * each entry out of the physical allocator free list and putting it 357 * onto a list for reporting via the vm.page_blacklist sysctl. 358 */ 359 static void 360 vm_page_blacklist_check(char *list, char *end) 361 { 362 vm_paddr_t pa; 363 char *next; 364 365 next = list; 366 while (next != NULL) { 367 if ((pa = vm_page_blacklist_next(&next, end)) == 0) 368 continue; 369 vm_page_blacklist_add(pa, bootverbose); 370 } 371 } 372 373 /* 374 * vm_page_blacklist_load: 375 * 376 * Search for a special module named "ram_blacklist". It'll be a 377 * plain text file provided by the user via the loader directive 378 * of the same name. 379 */ 380 static void 381 vm_page_blacklist_load(char **list, char **end) 382 { 383 void *mod; 384 u_char *ptr; 385 u_int len; 386 387 mod = NULL; 388 ptr = NULL; 389 390 mod = preload_search_by_type("ram_blacklist"); 391 if (mod != NULL) { 392 ptr = preload_fetch_addr(mod); 393 len = preload_fetch_size(mod); 394 } 395 *list = ptr; 396 if (ptr != NULL) 397 *end = ptr + len; 398 else 399 *end = NULL; 400 return; 401 } 402 403 static int 404 sysctl_vm_page_blacklist(SYSCTL_HANDLER_ARGS) 405 { 406 vm_page_t m; 407 struct sbuf sbuf; 408 int error, first; 409 410 first = 1; 411 error = sysctl_wire_old_buffer(req, 0); 412 if (error != 0) 413 return (error); 414 sbuf_new_for_sysctl(&sbuf, NULL, 128, req); 415 TAILQ_FOREACH(m, &blacklist_head, listq) { 416 sbuf_printf(&sbuf, "%s%#jx", first ? "" : ",", 417 (uintmax_t)m->phys_addr); 418 first = 0; 419 } 420 error = sbuf_finish(&sbuf); 421 sbuf_delete(&sbuf); 422 return (error); 423 } 424 425 /* 426 * Initialize a dummy page for use in scans of the specified paging queue. 427 * In principle, this function only needs to set the flag PG_MARKER. 428 * Nonetheless, it write busies the page as a safety precaution. 429 */ 430 void 431 vm_page_init_marker(vm_page_t marker, int queue, uint16_t aflags) 432 { 433 434 bzero(marker, sizeof(*marker)); 435 marker->flags = PG_MARKER; 436 marker->a.flags = aflags; 437 marker->busy_lock = VPB_CURTHREAD_EXCLUSIVE; 438 marker->a.queue = queue; 439 } 440 441 static void 442 vm_page_domain_init(int domain) 443 { 444 struct vm_domain *vmd; 445 struct vm_pagequeue *pq; 446 int i; 447 448 vmd = VM_DOMAIN(domain); 449 bzero(vmd, sizeof(*vmd)); 450 *__DECONST(const char **, &vmd->vmd_pagequeues[PQ_INACTIVE].pq_name) = 451 "vm inactive pagequeue"; 452 *__DECONST(const char **, &vmd->vmd_pagequeues[PQ_ACTIVE].pq_name) = 453 "vm active pagequeue"; 454 *__DECONST(const char **, &vmd->vmd_pagequeues[PQ_LAUNDRY].pq_name) = 455 "vm laundry pagequeue"; 456 *__DECONST(const char **, 457 &vmd->vmd_pagequeues[PQ_UNSWAPPABLE].pq_name) = 458 "vm unswappable pagequeue"; 459 vmd->vmd_domain = domain; 460 vmd->vmd_page_count = 0; 461 vmd->vmd_free_count = 0; 462 vmd->vmd_segs = 0; 463 vmd->vmd_oom = FALSE; 464 for (i = 0; i < PQ_COUNT; i++) { 465 pq = &vmd->vmd_pagequeues[i]; 466 TAILQ_INIT(&pq->pq_pl); 467 mtx_init(&pq->pq_mutex, pq->pq_name, "vm pagequeue", 468 MTX_DEF | MTX_DUPOK); 469 pq->pq_pdpages = 0; 470 vm_page_init_marker(&vmd->vmd_markers[i], i, 0); 471 } 472 mtx_init(&vmd->vmd_free_mtx, "vm page free queue", NULL, MTX_DEF); 473 mtx_init(&vmd->vmd_pageout_mtx, "vm pageout lock", NULL, MTX_DEF); 474 snprintf(vmd->vmd_name, sizeof(vmd->vmd_name), "%d", domain); 475 476 /* 477 * inacthead is used to provide FIFO ordering for LRU-bypassing 478 * insertions. 479 */ 480 vm_page_init_marker(&vmd->vmd_inacthead, PQ_INACTIVE, PGA_ENQUEUED); 481 TAILQ_INSERT_HEAD(&vmd->vmd_pagequeues[PQ_INACTIVE].pq_pl, 482 &vmd->vmd_inacthead, plinks.q); 483 484 /* 485 * The clock pages are used to implement active queue scanning without 486 * requeues. Scans start at clock[0], which is advanced after the scan 487 * ends. When the two clock hands meet, they are reset and scanning 488 * resumes from the head of the queue. 489 */ 490 vm_page_init_marker(&vmd->vmd_clock[0], PQ_ACTIVE, PGA_ENQUEUED); 491 vm_page_init_marker(&vmd->vmd_clock[1], PQ_ACTIVE, PGA_ENQUEUED); 492 TAILQ_INSERT_HEAD(&vmd->vmd_pagequeues[PQ_ACTIVE].pq_pl, 493 &vmd->vmd_clock[0], plinks.q); 494 TAILQ_INSERT_TAIL(&vmd->vmd_pagequeues[PQ_ACTIVE].pq_pl, 495 &vmd->vmd_clock[1], plinks.q); 496 } 497 498 /* 499 * Initialize a physical page in preparation for adding it to the free 500 * lists. 501 */ 502 void 503 vm_page_init_page(vm_page_t m, vm_paddr_t pa, int segind, int pool) 504 { 505 m->object = NULL; 506 m->ref_count = 0; 507 m->busy_lock = VPB_FREED; 508 m->flags = m->a.flags = 0; 509 m->phys_addr = pa; 510 m->a.queue = PQ_NONE; 511 m->psind = 0; 512 m->segind = segind; 513 m->order = VM_NFREEORDER; 514 m->pool = pool; 515 m->valid = m->dirty = 0; 516 pmap_page_init(m); 517 } 518 519 #ifndef PMAP_HAS_PAGE_ARRAY 520 static vm_paddr_t 521 vm_page_array_alloc(vm_offset_t *vaddr, vm_paddr_t end, vm_paddr_t page_range) 522 { 523 vm_paddr_t new_end; 524 525 /* 526 * Reserve an unmapped guard page to trap access to vm_page_array[-1]. 527 * However, because this page is allocated from KVM, out-of-bounds 528 * accesses using the direct map will not be trapped. 529 */ 530 *vaddr += PAGE_SIZE; 531 532 /* 533 * Allocate physical memory for the page structures, and map it. 534 */ 535 new_end = trunc_page(end - page_range * sizeof(struct vm_page)); 536 vm_page_array = (vm_page_t)pmap_map(vaddr, new_end, end, 537 VM_PROT_READ | VM_PROT_WRITE); 538 vm_page_array_size = page_range; 539 540 return (new_end); 541 } 542 #endif 543 544 /* 545 * vm_page_startup: 546 * 547 * Initializes the resident memory module. Allocates physical memory for 548 * bootstrapping UMA and some data structures that are used to manage 549 * physical pages. Initializes these structures, and populates the free 550 * page queues. 551 */ 552 vm_offset_t 553 vm_page_startup(vm_offset_t vaddr) 554 { 555 struct vm_phys_seg *seg; 556 struct vm_domain *vmd; 557 vm_page_t m; 558 char *list, *listend; 559 vm_paddr_t end, high_avail, low_avail, new_end, size; 560 vm_paddr_t page_range __unused; 561 vm_paddr_t last_pa, pa, startp, endp; 562 u_long pagecount; 563 #if MINIDUMP_PAGE_TRACKING 564 u_long vm_page_dump_size; 565 #endif 566 int biggestone, i, segind; 567 #ifdef WITNESS 568 vm_offset_t mapped; 569 int witness_size; 570 #endif 571 #if defined(__i386__) && defined(VM_PHYSSEG_DENSE) 572 long ii; 573 #endif 574 #ifdef VM_FREEPOOL_LAZYINIT 575 int lazyinit; 576 #endif 577 578 vaddr = round_page(vaddr); 579 580 vm_phys_early_startup(); 581 biggestone = vm_phys_avail_largest(); 582 end = phys_avail[biggestone+1]; 583 584 /* 585 * Initialize the page and queue locks. 586 */ 587 mtx_init(&vm_domainset_lock, "vm domainset lock", NULL, MTX_DEF); 588 for (i = 0; i < PA_LOCK_COUNT; i++) 589 mtx_init(&pa_lock[i], "vm page", NULL, MTX_DEF); 590 for (i = 0; i < vm_ndomains; i++) 591 vm_page_domain_init(i); 592 593 new_end = end; 594 #ifdef WITNESS 595 witness_size = round_page(witness_startup_count()); 596 new_end -= witness_size; 597 mapped = pmap_map(&vaddr, new_end, new_end + witness_size, 598 VM_PROT_READ | VM_PROT_WRITE); 599 bzero((void *)mapped, witness_size); 600 witness_startup((void *)mapped); 601 #endif 602 603 #if MINIDUMP_PAGE_TRACKING 604 /* 605 * Allocate a bitmap to indicate that a random physical page 606 * needs to be included in a minidump. 607 * 608 * The amd64 port needs this to indicate which direct map pages 609 * need to be dumped, via calls to dump_add_page()/dump_drop_page(). 610 * 611 * However, i386 still needs this workspace internally within the 612 * minidump code. In theory, they are not needed on i386, but are 613 * included should the sf_buf code decide to use them. 614 */ 615 last_pa = 0; 616 vm_page_dump_pages = 0; 617 for (i = 0; dump_avail[i + 1] != 0; i += 2) { 618 vm_page_dump_pages += howmany(dump_avail[i + 1], PAGE_SIZE) - 619 dump_avail[i] / PAGE_SIZE; 620 if (dump_avail[i + 1] > last_pa) 621 last_pa = dump_avail[i + 1]; 622 } 623 vm_page_dump_size = round_page(BITSET_SIZE(vm_page_dump_pages)); 624 new_end -= vm_page_dump_size; 625 vm_page_dump = (void *)(uintptr_t)pmap_map(&vaddr, new_end, 626 new_end + vm_page_dump_size, VM_PROT_READ | VM_PROT_WRITE); 627 bzero((void *)vm_page_dump, vm_page_dump_size); 628 #if MINIDUMP_STARTUP_PAGE_TRACKING 629 /* 630 * Include the UMA bootstrap pages, witness pages and vm_page_dump 631 * in a crash dump. When pmap_map() uses the direct map, they are 632 * not automatically included. 633 */ 634 for (pa = new_end; pa < end; pa += PAGE_SIZE) 635 dump_add_page(pa); 636 #endif 637 #else 638 (void)last_pa; 639 #endif 640 phys_avail[biggestone + 1] = new_end; 641 #ifdef __amd64__ 642 /* 643 * Request that the physical pages underlying the message buffer be 644 * included in a crash dump. Since the message buffer is accessed 645 * through the direct map, they are not automatically included. 646 */ 647 pa = DMAP_TO_PHYS((vm_offset_t)msgbufp->msg_ptr); 648 last_pa = pa + round_page(msgbufsize); 649 while (pa < last_pa) { 650 dump_add_page(pa); 651 pa += PAGE_SIZE; 652 } 653 #endif 654 /* 655 * Compute the number of pages of memory that will be available for 656 * use, taking into account the overhead of a page structure per page. 657 * In other words, solve 658 * "available physical memory" - round_page(page_range * 659 * sizeof(struct vm_page)) = page_range * PAGE_SIZE 660 * for page_range. 661 */ 662 low_avail = phys_avail[0]; 663 high_avail = phys_avail[1]; 664 for (i = 0; i < vm_phys_nsegs; i++) { 665 if (vm_phys_segs[i].start < low_avail) 666 low_avail = vm_phys_segs[i].start; 667 if (vm_phys_segs[i].end > high_avail) 668 high_avail = vm_phys_segs[i].end; 669 } 670 /* Skip the first chunk. It is already accounted for. */ 671 for (i = 2; phys_avail[i + 1] != 0; i += 2) { 672 if (phys_avail[i] < low_avail) 673 low_avail = phys_avail[i]; 674 if (phys_avail[i + 1] > high_avail) 675 high_avail = phys_avail[i + 1]; 676 } 677 first_page = low_avail / PAGE_SIZE; 678 #ifdef VM_PHYSSEG_SPARSE 679 size = 0; 680 for (i = 0; i < vm_phys_nsegs; i++) 681 size += vm_phys_segs[i].end - vm_phys_segs[i].start; 682 for (i = 0; phys_avail[i + 1] != 0; i += 2) 683 size += phys_avail[i + 1] - phys_avail[i]; 684 #elif defined(VM_PHYSSEG_DENSE) 685 size = high_avail - low_avail; 686 #else 687 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." 688 #endif 689 690 #ifdef PMAP_HAS_PAGE_ARRAY 691 pmap_page_array_startup(size / PAGE_SIZE); 692 biggestone = vm_phys_avail_largest(); 693 end = new_end = phys_avail[biggestone + 1]; 694 #else 695 #ifdef VM_PHYSSEG_DENSE 696 /* 697 * In the VM_PHYSSEG_DENSE case, the number of pages can account for 698 * the overhead of a page structure per page only if vm_page_array is 699 * allocated from the last physical memory chunk. Otherwise, we must 700 * allocate page structures representing the physical memory 701 * underlying vm_page_array, even though they will not be used. 702 */ 703 if (new_end != high_avail) 704 page_range = size / PAGE_SIZE; 705 else 706 #endif 707 { 708 page_range = size / (PAGE_SIZE + sizeof(struct vm_page)); 709 710 /* 711 * If the partial bytes remaining are large enough for 712 * a page (PAGE_SIZE) without a corresponding 713 * 'struct vm_page', then new_end will contain an 714 * extra page after subtracting the length of the VM 715 * page array. Compensate by subtracting an extra 716 * page from new_end. 717 */ 718 if (size % (PAGE_SIZE + sizeof(struct vm_page)) >= PAGE_SIZE) { 719 if (new_end == high_avail) 720 high_avail -= PAGE_SIZE; 721 new_end -= PAGE_SIZE; 722 } 723 } 724 end = new_end; 725 new_end = vm_page_array_alloc(&vaddr, end, page_range); 726 #endif 727 728 #if VM_NRESERVLEVEL > 0 729 /* 730 * Allocate physical memory for the reservation management system's 731 * data structures, and map it. 732 */ 733 new_end = vm_reserv_startup(&vaddr, new_end); 734 #endif 735 #if MINIDUMP_PAGE_TRACKING && MINIDUMP_STARTUP_PAGE_TRACKING 736 /* 737 * Include vm_page_array and vm_reserv_array in a crash dump. 738 */ 739 for (pa = new_end; pa < end; pa += PAGE_SIZE) 740 dump_add_page(pa); 741 #endif 742 phys_avail[biggestone + 1] = new_end; 743 744 /* 745 * Add physical memory segments corresponding to the available 746 * physical pages. 747 */ 748 for (i = 0; phys_avail[i + 1] != 0; i += 2) 749 if (vm_phys_avail_size(i) != 0) 750 vm_phys_add_seg(phys_avail[i], phys_avail[i + 1]); 751 752 /* 753 * Initialize the physical memory allocator. 754 */ 755 vm_phys_init(); 756 757 #ifdef VM_FREEPOOL_LAZYINIT 758 lazyinit = 1; 759 TUNABLE_INT_FETCH("debug.vm.lazy_page_init", &lazyinit); 760 #endif 761 762 /* 763 * Initialize the page structures and add every available page to the 764 * physical memory allocator's free lists. 765 */ 766 #if defined(__i386__) && defined(VM_PHYSSEG_DENSE) 767 for (ii = 0; ii < vm_page_array_size; ii++) { 768 m = &vm_page_array[ii]; 769 vm_page_init_page(m, (first_page + ii) << PAGE_SHIFT, 0, 770 VM_FREEPOOL_DEFAULT); 771 m->flags = PG_FICTITIOUS; 772 } 773 #endif 774 vm_cnt.v_page_count = 0; 775 for (segind = 0; segind < vm_phys_nsegs; segind++) { 776 seg = &vm_phys_segs[segind]; 777 778 /* 779 * If lazy vm_page initialization is not enabled, simply 780 * initialize all of the pages in the segment. Otherwise, we 781 * only initialize: 782 * 1. Pages not covered by phys_avail[], since they might be 783 * freed to the allocator at some future point, e.g., by 784 * kmem_bootstrap_free(). 785 * 2. The first page of each run of free pages handed to the 786 * vm_phys allocator, which in turn defers initialization 787 * of pages until they are needed. 788 * This avoids blocking the boot process for long periods, which 789 * may be relevant for VMs (which ought to boot as quickly as 790 * possible) and/or systems with large amounts of physical 791 * memory. 792 */ 793 #ifdef VM_FREEPOOL_LAZYINIT 794 if (lazyinit) { 795 startp = seg->start; 796 for (i = 0; phys_avail[i + 1] != 0; i += 2) { 797 if (startp >= seg->end) 798 break; 799 800 if (phys_avail[i + 1] < startp) 801 continue; 802 if (phys_avail[i] <= startp) { 803 startp = phys_avail[i + 1]; 804 continue; 805 } 806 807 m = vm_phys_seg_paddr_to_vm_page(seg, startp); 808 for (endp = MIN(phys_avail[i], seg->end); 809 startp < endp; startp += PAGE_SIZE, m++) { 810 vm_page_init_page(m, startp, segind, 811 VM_FREEPOOL_DEFAULT); 812 } 813 } 814 } else 815 #endif 816 for (m = seg->first_page, pa = seg->start; 817 pa < seg->end; m++, pa += PAGE_SIZE) { 818 vm_page_init_page(m, pa, segind, 819 VM_FREEPOOL_DEFAULT); 820 } 821 822 /* 823 * Add the segment's pages that are covered by one of 824 * phys_avail's ranges to the free lists. 825 */ 826 for (i = 0; phys_avail[i + 1] != 0; i += 2) { 827 if (seg->end <= phys_avail[i] || 828 seg->start >= phys_avail[i + 1]) 829 continue; 830 831 startp = MAX(seg->start, phys_avail[i]); 832 endp = MIN(seg->end, phys_avail[i + 1]); 833 pagecount = (u_long)atop(endp - startp); 834 if (pagecount == 0) 835 continue; 836 837 m = vm_phys_seg_paddr_to_vm_page(seg, startp); 838 #ifdef VM_FREEPOOL_LAZYINIT 839 if (lazyinit) { 840 vm_page_init_page(m, startp, segind, 841 VM_FREEPOOL_LAZYINIT); 842 } 843 #endif 844 vmd = VM_DOMAIN(seg->domain); 845 vm_domain_free_lock(vmd); 846 vm_phys_enqueue_contig(m, pagecount); 847 vm_domain_free_unlock(vmd); 848 vm_domain_freecnt_inc(vmd, pagecount); 849 vm_cnt.v_page_count += (u_int)pagecount; 850 vmd->vmd_page_count += (u_int)pagecount; 851 vmd->vmd_segs |= 1UL << segind; 852 } 853 } 854 855 /* 856 * Remove blacklisted pages from the physical memory allocator. 857 */ 858 TAILQ_INIT(&blacklist_head); 859 vm_page_blacklist_load(&list, &listend); 860 vm_page_blacklist_check(list, listend); 861 862 list = kern_getenv("vm.blacklist"); 863 vm_page_blacklist_check(list, NULL); 864 865 freeenv(list); 866 #if VM_NRESERVLEVEL > 0 867 /* 868 * Initialize the reservation management system. 869 */ 870 vm_reserv_init(); 871 #endif 872 873 return (vaddr); 874 } 875 876 void 877 vm_page_reference(vm_page_t m) 878 { 879 880 vm_page_aflag_set(m, PGA_REFERENCED); 881 } 882 883 /* 884 * vm_page_trybusy 885 * 886 * Helper routine for grab functions to trylock busy. 887 * 888 * Returns true on success and false on failure. 889 */ 890 static bool 891 vm_page_trybusy(vm_page_t m, int allocflags) 892 { 893 894 if ((allocflags & (VM_ALLOC_SBUSY | VM_ALLOC_IGN_SBUSY)) != 0) 895 return (vm_page_trysbusy(m)); 896 else 897 return (vm_page_tryxbusy(m)); 898 } 899 900 /* 901 * vm_page_tryacquire 902 * 903 * Helper routine for grab functions to trylock busy and wire. 904 * 905 * Returns true on success and false on failure. 906 */ 907 static inline bool 908 vm_page_tryacquire(vm_page_t m, int allocflags) 909 { 910 bool locked; 911 912 locked = vm_page_trybusy(m, allocflags); 913 if (locked && (allocflags & VM_ALLOC_WIRED) != 0) 914 vm_page_wire(m); 915 return (locked); 916 } 917 918 /* 919 * vm_page_busy_acquire: 920 * 921 * Acquire the busy lock as described by VM_ALLOC_* flags. Will loop 922 * and drop the object lock if necessary. 923 */ 924 bool 925 vm_page_busy_acquire(vm_page_t m, int allocflags) 926 { 927 vm_object_t obj; 928 bool locked; 929 930 /* 931 * The page-specific object must be cached because page 932 * identity can change during the sleep, causing the 933 * re-lock of a different object. 934 * It is assumed that a reference to the object is already 935 * held by the callers. 936 */ 937 obj = atomic_load_ptr(&m->object); 938 for (;;) { 939 if (vm_page_tryacquire(m, allocflags)) 940 return (true); 941 if ((allocflags & VM_ALLOC_NOWAIT) != 0) 942 return (false); 943 if (obj != NULL) 944 locked = VM_OBJECT_WOWNED(obj); 945 else 946 locked = false; 947 MPASS(locked || vm_page_wired(m)); 948 if (_vm_page_busy_sleep(obj, m, m->pindex, "vmpba", allocflags, 949 locked) && locked) 950 VM_OBJECT_WLOCK(obj); 951 if ((allocflags & VM_ALLOC_WAITFAIL) != 0) 952 return (false); 953 KASSERT(m->object == obj || m->object == NULL, 954 ("vm_page_busy_acquire: page %p does not belong to %p", 955 m, obj)); 956 } 957 } 958 959 /* 960 * vm_page_busy_downgrade: 961 * 962 * Downgrade an exclusive busy page into a single shared busy page. 963 */ 964 void 965 vm_page_busy_downgrade(vm_page_t m) 966 { 967 u_int x; 968 969 vm_page_assert_xbusied(m); 970 971 x = vm_page_busy_fetch(m); 972 for (;;) { 973 if (atomic_fcmpset_rel_int(&m->busy_lock, 974 &x, VPB_SHARERS_WORD(1))) 975 break; 976 } 977 if ((x & VPB_BIT_WAITERS) != 0) 978 wakeup(m); 979 } 980 981 /* 982 * 983 * vm_page_busy_tryupgrade: 984 * 985 * Attempt to upgrade a single shared busy into an exclusive busy. 986 */ 987 int 988 vm_page_busy_tryupgrade(vm_page_t m) 989 { 990 u_int ce, x; 991 992 vm_page_assert_sbusied(m); 993 994 x = vm_page_busy_fetch(m); 995 ce = VPB_CURTHREAD_EXCLUSIVE; 996 for (;;) { 997 if (VPB_SHARERS(x) > 1) 998 return (0); 999 KASSERT((x & ~VPB_BIT_WAITERS) == VPB_SHARERS_WORD(1), 1000 ("vm_page_busy_tryupgrade: invalid lock state")); 1001 if (!atomic_fcmpset_acq_int(&m->busy_lock, &x, 1002 ce | (x & VPB_BIT_WAITERS))) 1003 continue; 1004 return (1); 1005 } 1006 } 1007 1008 /* 1009 * vm_page_sbusied: 1010 * 1011 * Return a positive value if the page is shared busied, 0 otherwise. 1012 */ 1013 int 1014 vm_page_sbusied(vm_page_t m) 1015 { 1016 u_int x; 1017 1018 x = vm_page_busy_fetch(m); 1019 return ((x & VPB_BIT_SHARED) != 0 && x != VPB_UNBUSIED); 1020 } 1021 1022 /* 1023 * vm_page_sunbusy: 1024 * 1025 * Shared unbusy a page. 1026 */ 1027 void 1028 vm_page_sunbusy(vm_page_t m) 1029 { 1030 u_int x; 1031 1032 vm_page_assert_sbusied(m); 1033 1034 x = vm_page_busy_fetch(m); 1035 for (;;) { 1036 KASSERT(x != VPB_FREED, 1037 ("vm_page_sunbusy: Unlocking freed page.")); 1038 if (VPB_SHARERS(x) > 1) { 1039 if (atomic_fcmpset_int(&m->busy_lock, &x, 1040 x - VPB_ONE_SHARER)) 1041 break; 1042 continue; 1043 } 1044 KASSERT((x & ~VPB_BIT_WAITERS) == VPB_SHARERS_WORD(1), 1045 ("vm_page_sunbusy: invalid lock state")); 1046 if (!atomic_fcmpset_rel_int(&m->busy_lock, &x, VPB_UNBUSIED)) 1047 continue; 1048 if ((x & VPB_BIT_WAITERS) == 0) 1049 break; 1050 wakeup(m); 1051 break; 1052 } 1053 } 1054 1055 /* 1056 * vm_page_busy_sleep: 1057 * 1058 * Sleep if the page is busy, using the page pointer as wchan. 1059 * This is used to implement the hard-path of the busying mechanism. 1060 * 1061 * If VM_ALLOC_IGN_SBUSY is specified in allocflags, the function 1062 * will not sleep if the page is shared-busy. 1063 * 1064 * The object lock must be held on entry. 1065 * 1066 * Returns true if it slept and dropped the object lock, or false 1067 * if there was no sleep and the lock is still held. 1068 */ 1069 bool 1070 vm_page_busy_sleep(vm_page_t m, const char *wmesg, int allocflags) 1071 { 1072 vm_object_t obj; 1073 1074 obj = m->object; 1075 VM_OBJECT_ASSERT_LOCKED(obj); 1076 1077 return (_vm_page_busy_sleep(obj, m, m->pindex, wmesg, allocflags, 1078 true)); 1079 } 1080 1081 /* 1082 * vm_page_busy_sleep_unlocked: 1083 * 1084 * Sleep if the page is busy, using the page pointer as wchan. 1085 * This is used to implement the hard-path of busying mechanism. 1086 * 1087 * If VM_ALLOC_IGN_SBUSY is specified in allocflags, the function 1088 * will not sleep if the page is shared-busy. 1089 * 1090 * The object lock must not be held on entry. The operation will 1091 * return if the page changes identity. 1092 */ 1093 void 1094 vm_page_busy_sleep_unlocked(vm_object_t obj, vm_page_t m, vm_pindex_t pindex, 1095 const char *wmesg, int allocflags) 1096 { 1097 VM_OBJECT_ASSERT_UNLOCKED(obj); 1098 1099 (void)_vm_page_busy_sleep(obj, m, pindex, wmesg, allocflags, false); 1100 } 1101 1102 /* 1103 * _vm_page_busy_sleep: 1104 * 1105 * Internal busy sleep function. Verifies the page identity and 1106 * lockstate against parameters. Returns true if it sleeps and 1107 * false otherwise. 1108 * 1109 * allocflags uses VM_ALLOC_* flags to specify the lock required. 1110 * 1111 * If locked is true the lock will be dropped for any true returns 1112 * and held for any false returns. 1113 */ 1114 static bool 1115 _vm_page_busy_sleep(vm_object_t obj, vm_page_t m, vm_pindex_t pindex, 1116 const char *wmesg, int allocflags, bool locked) 1117 { 1118 bool xsleep; 1119 u_int x; 1120 1121 /* 1122 * If the object is busy we must wait for that to drain to zero 1123 * before trying the page again. 1124 */ 1125 if (obj != NULL && vm_object_busied(obj)) { 1126 if (locked) 1127 VM_OBJECT_DROP(obj); 1128 vm_object_busy_wait(obj, wmesg); 1129 return (true); 1130 } 1131 1132 if (!vm_page_busied(m)) 1133 return (false); 1134 1135 xsleep = (allocflags & (VM_ALLOC_SBUSY | VM_ALLOC_IGN_SBUSY)) != 0; 1136 sleepq_lock(m); 1137 x = vm_page_busy_fetch(m); 1138 do { 1139 /* 1140 * If the page changes objects or becomes unlocked we can 1141 * simply return. 1142 */ 1143 if (x == VPB_UNBUSIED || 1144 (xsleep && (x & VPB_BIT_SHARED) != 0) || 1145 m->object != obj || m->pindex != pindex) { 1146 sleepq_release(m); 1147 return (false); 1148 } 1149 if ((x & VPB_BIT_WAITERS) != 0) 1150 break; 1151 } while (!atomic_fcmpset_int(&m->busy_lock, &x, x | VPB_BIT_WAITERS)); 1152 if (locked) 1153 VM_OBJECT_DROP(obj); 1154 DROP_GIANT(); 1155 sleepq_add(m, NULL, wmesg, 0, 0); 1156 sleepq_wait(m, PVM); 1157 PICKUP_GIANT(); 1158 return (true); 1159 } 1160 1161 /* 1162 * vm_page_trysbusy: 1163 * 1164 * Try to shared busy a page. 1165 * If the operation succeeds 1 is returned otherwise 0. 1166 * The operation never sleeps. 1167 */ 1168 int 1169 vm_page_trysbusy(vm_page_t m) 1170 { 1171 vm_object_t obj; 1172 u_int x; 1173 1174 obj = m->object; 1175 x = vm_page_busy_fetch(m); 1176 for (;;) { 1177 if ((x & VPB_BIT_SHARED) == 0) 1178 return (0); 1179 /* 1180 * Reduce the window for transient busies that will trigger 1181 * false negatives in vm_page_ps_test(). 1182 */ 1183 if (obj != NULL && vm_object_busied(obj)) 1184 return (0); 1185 if (atomic_fcmpset_acq_int(&m->busy_lock, &x, 1186 x + VPB_ONE_SHARER)) 1187 break; 1188 } 1189 1190 /* Refetch the object now that we're guaranteed that it is stable. */ 1191 obj = m->object; 1192 if (obj != NULL && vm_object_busied(obj)) { 1193 vm_page_sunbusy(m); 1194 return (0); 1195 } 1196 return (1); 1197 } 1198 1199 /* 1200 * vm_page_tryxbusy: 1201 * 1202 * Try to exclusive busy a page. 1203 * If the operation succeeds 1 is returned otherwise 0. 1204 * The operation never sleeps. 1205 */ 1206 int 1207 vm_page_tryxbusy(vm_page_t m) 1208 { 1209 vm_object_t obj; 1210 1211 if (atomic_cmpset_acq_int(&m->busy_lock, VPB_UNBUSIED, 1212 VPB_CURTHREAD_EXCLUSIVE) == 0) 1213 return (0); 1214 1215 obj = m->object; 1216 if (obj != NULL && vm_object_busied(obj)) { 1217 vm_page_xunbusy(m); 1218 return (0); 1219 } 1220 return (1); 1221 } 1222 1223 static void 1224 vm_page_xunbusy_hard_tail(vm_page_t m) 1225 { 1226 atomic_store_rel_int(&m->busy_lock, VPB_UNBUSIED); 1227 /* Wake the waiter. */ 1228 wakeup(m); 1229 } 1230 1231 /* 1232 * vm_page_xunbusy_hard: 1233 * 1234 * Called when unbusy has failed because there is a waiter. 1235 */ 1236 void 1237 vm_page_xunbusy_hard(vm_page_t m) 1238 { 1239 vm_page_assert_xbusied(m); 1240 vm_page_xunbusy_hard_tail(m); 1241 } 1242 1243 void 1244 vm_page_xunbusy_hard_unchecked(vm_page_t m) 1245 { 1246 vm_page_assert_xbusied_unchecked(m); 1247 vm_page_xunbusy_hard_tail(m); 1248 } 1249 1250 static void 1251 vm_page_busy_free(vm_page_t m) 1252 { 1253 u_int x; 1254 1255 atomic_thread_fence_rel(); 1256 x = atomic_swap_int(&m->busy_lock, VPB_FREED); 1257 if ((x & VPB_BIT_WAITERS) != 0) 1258 wakeup(m); 1259 } 1260 1261 /* 1262 * vm_page_unhold_pages: 1263 * 1264 * Unhold each of the pages that is referenced by the given array. 1265 */ 1266 void 1267 vm_page_unhold_pages(vm_page_t *ma, int count) 1268 { 1269 1270 for (; count != 0; count--) { 1271 vm_page_unwire(*ma, PQ_ACTIVE); 1272 ma++; 1273 } 1274 } 1275 1276 vm_page_t 1277 PHYS_TO_VM_PAGE(vm_paddr_t pa) 1278 { 1279 vm_page_t m; 1280 1281 #ifdef VM_PHYSSEG_SPARSE 1282 m = vm_phys_paddr_to_vm_page(pa); 1283 if (m == NULL) 1284 m = vm_phys_fictitious_to_vm_page(pa); 1285 return (m); 1286 #elif defined(VM_PHYSSEG_DENSE) 1287 long pi; 1288 1289 pi = atop(pa); 1290 if (pi >= first_page && (pi - first_page) < vm_page_array_size) { 1291 m = &vm_page_array[pi - first_page]; 1292 return (m); 1293 } 1294 return (vm_phys_fictitious_to_vm_page(pa)); 1295 #else 1296 #error "Either VM_PHYSSEG_DENSE or VM_PHYSSEG_SPARSE must be defined." 1297 #endif 1298 } 1299 1300 /* 1301 * vm_page_getfake: 1302 * 1303 * Create a fictitious page with the specified physical address and 1304 * memory attribute. The memory attribute is the only the machine- 1305 * dependent aspect of a fictitious page that must be initialized. 1306 */ 1307 vm_page_t 1308 vm_page_getfake(vm_paddr_t paddr, vm_memattr_t memattr) 1309 { 1310 vm_page_t m; 1311 1312 m = uma_zalloc(fakepg_zone, M_WAITOK | M_ZERO); 1313 vm_page_initfake(m, paddr, memattr); 1314 return (m); 1315 } 1316 1317 void 1318 vm_page_initfake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) 1319 { 1320 1321 if ((m->flags & PG_FICTITIOUS) != 0) { 1322 /* 1323 * The page's memattr might have changed since the 1324 * previous initialization. Update the pmap to the 1325 * new memattr. 1326 */ 1327 goto memattr; 1328 } 1329 m->phys_addr = paddr; 1330 m->a.queue = PQ_NONE; 1331 /* Fictitious pages don't use "segind". */ 1332 m->flags = PG_FICTITIOUS; 1333 /* Fictitious pages don't use "order" or "pool". */ 1334 m->oflags = VPO_UNMANAGED; 1335 m->busy_lock = VPB_CURTHREAD_EXCLUSIVE; 1336 /* Fictitious pages are unevictable. */ 1337 m->ref_count = 1; 1338 pmap_page_init(m); 1339 memattr: 1340 pmap_page_set_memattr(m, memattr); 1341 } 1342 1343 /* 1344 * vm_page_putfake: 1345 * 1346 * Release a fictitious page. 1347 */ 1348 void 1349 vm_page_putfake(vm_page_t m) 1350 { 1351 1352 KASSERT((m->oflags & VPO_UNMANAGED) != 0, ("managed %p", m)); 1353 KASSERT((m->flags & PG_FICTITIOUS) != 0, 1354 ("vm_page_putfake: bad page %p", m)); 1355 vm_page_assert_xbusied(m); 1356 vm_page_busy_free(m); 1357 uma_zfree(fakepg_zone, m); 1358 } 1359 1360 /* 1361 * vm_page_updatefake: 1362 * 1363 * Update the given fictitious page to the specified physical address and 1364 * memory attribute. 1365 */ 1366 void 1367 vm_page_updatefake(vm_page_t m, vm_paddr_t paddr, vm_memattr_t memattr) 1368 { 1369 1370 KASSERT((m->flags & PG_FICTITIOUS) != 0, 1371 ("vm_page_updatefake: bad page %p", m)); 1372 m->phys_addr = paddr; 1373 pmap_page_set_memattr(m, memattr); 1374 } 1375 1376 /* 1377 * vm_page_free: 1378 * 1379 * Free a page. 1380 */ 1381 void 1382 vm_page_free(vm_page_t m) 1383 { 1384 1385 m->flags &= ~PG_ZERO; 1386 vm_page_free_toq(m); 1387 } 1388 1389 /* 1390 * vm_page_free_zero: 1391 * 1392 * Free a page to the zerod-pages queue 1393 */ 1394 void 1395 vm_page_free_zero(vm_page_t m) 1396 { 1397 1398 m->flags |= PG_ZERO; 1399 vm_page_free_toq(m); 1400 } 1401 1402 /* 1403 * Unbusy and handle the page queueing for a page from a getpages request that 1404 * was optionally read ahead or behind. 1405 */ 1406 void 1407 vm_page_readahead_finish(vm_page_t m) 1408 { 1409 1410 /* We shouldn't put invalid pages on queues. */ 1411 KASSERT(!vm_page_none_valid(m), ("%s: %p is invalid", __func__, m)); 1412 1413 /* 1414 * Since the page is not the actually needed one, whether it should 1415 * be activated or deactivated is not obvious. Empirical results 1416 * have shown that deactivating the page is usually the best choice, 1417 * unless the page is wanted by another thread. 1418 */ 1419 if ((vm_page_busy_fetch(m) & VPB_BIT_WAITERS) != 0) 1420 vm_page_activate(m); 1421 else 1422 vm_page_deactivate(m); 1423 vm_page_xunbusy_unchecked(m); 1424 } 1425 1426 /* 1427 * Destroy the identity of an invalid page and free it if possible. 1428 * This is intended to be used when reading a page from backing store fails. 1429 */ 1430 void 1431 vm_page_free_invalid(vm_page_t m) 1432 { 1433 1434 KASSERT(vm_page_none_valid(m), ("page %p is valid", m)); 1435 KASSERT(!pmap_page_is_mapped(m), ("page %p is mapped", m)); 1436 KASSERT(m->object != NULL, ("page %p has no object", m)); 1437 VM_OBJECT_ASSERT_WLOCKED(m->object); 1438 1439 /* 1440 * We may be attempting to free the page as part of the handling for an 1441 * I/O error, in which case the page was xbusied by a different thread. 1442 */ 1443 vm_page_xbusy_claim(m); 1444 1445 /* 1446 * If someone has wired this page while the object lock 1447 * was not held, then the thread that unwires is responsible 1448 * for freeing the page. Otherwise just free the page now. 1449 * The wire count of this unmapped page cannot change while 1450 * we have the page xbusy and the page's object wlocked. 1451 */ 1452 if (vm_page_remove(m)) 1453 vm_page_free(m); 1454 } 1455 1456 /* 1457 * vm_page_dirty_KBI: [ internal use only ] 1458 * 1459 * Set all bits in the page's dirty field. 1460 * 1461 * The object containing the specified page must be locked if the 1462 * call is made from the machine-independent layer. 1463 * 1464 * See vm_page_clear_dirty_mask(). 1465 * 1466 * This function should only be called by vm_page_dirty(). 1467 */ 1468 void 1469 vm_page_dirty_KBI(vm_page_t m) 1470 { 1471 1472 /* Refer to this operation by its public name. */ 1473 KASSERT(vm_page_all_valid(m), ("vm_page_dirty: page is invalid!")); 1474 m->dirty = VM_PAGE_BITS_ALL; 1475 } 1476 1477 /* 1478 * Insert the given page into the given object at the given pindex. mpred is 1479 * used for memq linkage. From vm_page_insert, lookup is true, mpred is 1480 * initially NULL, and this procedure looks it up. From vm_page_insert_after 1481 * and vm_page_iter_insert, lookup is false and mpred is known to the caller 1482 * to be valid, and may be NULL if this will be the page with the lowest 1483 * pindex. 1484 * 1485 * The procedure is marked __always_inline to suggest to the compiler to 1486 * eliminate the lookup parameter and the associated alternate branch. 1487 */ 1488 static __always_inline int 1489 vm_page_insert_lookup(vm_page_t m, vm_object_t object, vm_pindex_t pindex, 1490 struct pctrie_iter *pages, bool iter, vm_page_t mpred, bool lookup) 1491 { 1492 int error; 1493 1494 VM_OBJECT_ASSERT_WLOCKED(object); 1495 KASSERT(m->object == NULL, 1496 ("vm_page_insert: page %p already inserted", m)); 1497 1498 /* 1499 * Record the object/offset pair in this page. 1500 */ 1501 m->object = object; 1502 m->pindex = pindex; 1503 m->ref_count |= VPRC_OBJREF; 1504 1505 /* 1506 * Add this page to the object's radix tree, and look up mpred if 1507 * needed. 1508 */ 1509 if (iter) { 1510 KASSERT(!lookup, ("%s: cannot lookup mpred", __func__)); 1511 error = vm_radix_iter_insert(pages, m); 1512 } else if (lookup) 1513 error = vm_radix_insert_lookup_lt(&object->rtree, m, &mpred); 1514 else 1515 error = vm_radix_insert(&object->rtree, m); 1516 if (__predict_false(error != 0)) { 1517 m->object = NULL; 1518 m->pindex = 0; 1519 m->ref_count &= ~VPRC_OBJREF; 1520 return (1); 1521 } 1522 1523 /* 1524 * Now link into the object's ordered list of backed pages. 1525 */ 1526 vm_page_insert_radixdone(m, object, mpred); 1527 vm_pager_page_inserted(object, m); 1528 return (0); 1529 } 1530 1531 /* 1532 * vm_page_insert: [ internal use only ] 1533 * 1534 * Inserts the given mem entry into the object and object list. 1535 * 1536 * The object must be locked. 1537 */ 1538 int 1539 vm_page_insert(vm_page_t m, vm_object_t object, vm_pindex_t pindex) 1540 { 1541 return (vm_page_insert_lookup(m, object, pindex, NULL, false, NULL, 1542 true)); 1543 } 1544 1545 /* 1546 * vm_page_insert_after: 1547 * 1548 * Inserts the page "m" into the specified object at offset "pindex". 1549 * 1550 * The page "mpred" must immediately precede the offset "pindex" within 1551 * the specified object. 1552 * 1553 * The object must be locked. 1554 */ 1555 static int 1556 vm_page_insert_after(vm_page_t m, vm_object_t object, vm_pindex_t pindex, 1557 vm_page_t mpred) 1558 { 1559 return (vm_page_insert_lookup(m, object, pindex, NULL, false, mpred, 1560 false)); 1561 } 1562 1563 /* 1564 * vm_page_iter_insert: 1565 * 1566 * Tries to insert the page "m" into the specified object at offset 1567 * "pindex" using the iterator "pages". Returns 0 if the insertion was 1568 * successful. 1569 * 1570 * The page "mpred" must immediately precede the offset "pindex" within 1571 * the specified object. 1572 * 1573 * The object must be locked. 1574 */ 1575 static int 1576 vm_page_iter_insert(struct pctrie_iter *pages, vm_page_t m, vm_object_t object, 1577 vm_pindex_t pindex, vm_page_t mpred) 1578 { 1579 return (vm_page_insert_lookup(m, object, pindex, pages, true, mpred, 1580 false)); 1581 } 1582 1583 /* 1584 * vm_page_insert_radixdone: 1585 * 1586 * Complete page "m" insertion into the specified object after the 1587 * radix trie hooking. 1588 * 1589 * The page "mpred" must precede the offset "m->pindex" within the 1590 * specified object. 1591 * 1592 * The object must be locked. 1593 */ 1594 static void 1595 vm_page_insert_radixdone(vm_page_t m, vm_object_t object, vm_page_t mpred) 1596 { 1597 1598 VM_OBJECT_ASSERT_WLOCKED(object); 1599 KASSERT(object != NULL && m->object == object, 1600 ("vm_page_insert_radixdone: page %p has inconsistent object", m)); 1601 KASSERT((m->ref_count & VPRC_OBJREF) != 0, 1602 ("vm_page_insert_radixdone: page %p is missing object ref", m)); 1603 if (mpred != NULL) { 1604 KASSERT(mpred->object == object, 1605 ("vm_page_insert_radixdone: object doesn't contain mpred")); 1606 KASSERT(mpred->pindex < m->pindex, 1607 ("vm_page_insert_radixdone: mpred doesn't precede pindex")); 1608 KASSERT(TAILQ_NEXT(mpred, listq) == NULL || 1609 m->pindex < TAILQ_NEXT(mpred, listq)->pindex, 1610 ("vm_page_insert_radixdone: pindex doesn't precede msucc")); 1611 } else { 1612 KASSERT(TAILQ_EMPTY(&object->memq) || 1613 m->pindex < TAILQ_FIRST(&object->memq)->pindex, 1614 ("vm_page_insert_radixdone: no mpred but not first page")); 1615 } 1616 1617 if (mpred != NULL) 1618 TAILQ_INSERT_AFTER(&object->memq, mpred, m, listq); 1619 else 1620 TAILQ_INSERT_HEAD(&object->memq, m, listq); 1621 1622 /* 1623 * Show that the object has one more resident page. 1624 */ 1625 object->resident_page_count++; 1626 1627 /* 1628 * Hold the vnode until the last page is released. 1629 */ 1630 if (object->resident_page_count == 1 && object->type == OBJT_VNODE) 1631 vhold(object->handle); 1632 1633 /* 1634 * Since we are inserting a new and possibly dirty page, 1635 * update the object's generation count. 1636 */ 1637 if (pmap_page_is_write_mapped(m)) 1638 vm_object_set_writeable_dirty(object); 1639 } 1640 1641 /* 1642 * vm_page_remove_radixdone 1643 * 1644 * Complete page "m" removal from the specified object after the radix trie 1645 * unhooking. 1646 * 1647 * The caller is responsible for updating the page's fields to reflect this 1648 * removal. 1649 */ 1650 static void 1651 vm_page_remove_radixdone(vm_page_t m) 1652 { 1653 vm_object_t object; 1654 1655 vm_page_assert_xbusied(m); 1656 object = m->object; 1657 VM_OBJECT_ASSERT_WLOCKED(object); 1658 KASSERT((m->ref_count & VPRC_OBJREF) != 0, 1659 ("page %p is missing its object ref", m)); 1660 1661 /* Deferred free of swap space. */ 1662 if ((m->a.flags & PGA_SWAP_FREE) != 0) 1663 vm_pager_page_unswapped(m); 1664 1665 vm_pager_page_removed(object, m); 1666 m->object = NULL; 1667 1668 /* 1669 * Now remove from the object's list of backed pages. 1670 */ 1671 TAILQ_REMOVE(&object->memq, m, listq); 1672 1673 /* 1674 * And show that the object has one fewer resident page. 1675 */ 1676 object->resident_page_count--; 1677 1678 /* 1679 * The vnode may now be recycled. 1680 */ 1681 if (object->resident_page_count == 0 && object->type == OBJT_VNODE) 1682 vdrop(object->handle); 1683 } 1684 1685 /* 1686 * vm_page_free_object_prep: 1687 * 1688 * Disassociates the given page from its VM object. 1689 * 1690 * The object must be locked, and the page must be xbusy. 1691 */ 1692 static void 1693 vm_page_free_object_prep(vm_page_t m) 1694 { 1695 KASSERT(((m->oflags & VPO_UNMANAGED) != 0) == 1696 ((m->object->flags & OBJ_UNMANAGED) != 0), 1697 ("%s: managed flag mismatch for page %p", 1698 __func__, m)); 1699 vm_page_assert_xbusied(m); 1700 1701 /* 1702 * The object reference can be released without an atomic 1703 * operation. 1704 */ 1705 KASSERT((m->flags & PG_FICTITIOUS) != 0 || 1706 m->ref_count == VPRC_OBJREF, 1707 ("%s: page %p has unexpected ref_count %u", 1708 __func__, m, m->ref_count)); 1709 vm_page_remove_radixdone(m); 1710 m->ref_count -= VPRC_OBJREF; 1711 } 1712 1713 /* 1714 * vm_page_iter_free: 1715 * 1716 * Free the given page, and use the iterator to remove it from the radix 1717 * tree. 1718 */ 1719 void 1720 vm_page_iter_free(struct pctrie_iter *pages, vm_page_t m) 1721 { 1722 vm_radix_iter_remove(pages); 1723 vm_page_free_object_prep(m); 1724 vm_page_xunbusy(m); 1725 m->flags &= ~PG_ZERO; 1726 vm_page_free_toq(m); 1727 } 1728 1729 /* 1730 * vm_page_remove: 1731 * 1732 * Removes the specified page from its containing object, but does not 1733 * invalidate any backing storage. Returns true if the object's reference 1734 * was the last reference to the page, and false otherwise. 1735 * 1736 * The object must be locked and the page must be exclusively busied. 1737 * The exclusive busy will be released on return. If this is not the 1738 * final ref and the caller does not hold a wire reference it may not 1739 * continue to access the page. 1740 */ 1741 bool 1742 vm_page_remove(vm_page_t m) 1743 { 1744 bool dropped; 1745 1746 dropped = vm_page_remove_xbusy(m); 1747 vm_page_xunbusy(m); 1748 1749 return (dropped); 1750 } 1751 1752 /* 1753 * vm_page_iter_remove: 1754 * 1755 * Remove the current page, as identified by iterator, and remove it from the 1756 * radix tree. 1757 */ 1758 bool 1759 vm_page_iter_remove(struct pctrie_iter *pages) 1760 { 1761 vm_page_t m; 1762 bool dropped; 1763 1764 m = vm_radix_iter_page(pages); 1765 vm_radix_iter_remove(pages); 1766 vm_page_remove_radixdone(m); 1767 dropped = (vm_page_drop(m, VPRC_OBJREF) == VPRC_OBJREF); 1768 vm_page_xunbusy(m); 1769 1770 return (dropped); 1771 } 1772 1773 /* 1774 * vm_page_radix_remove 1775 * 1776 * Removes the specified page from the radix tree. 1777 */ 1778 static void 1779 vm_page_radix_remove(vm_page_t m) 1780 { 1781 vm_page_t mrem __diagused; 1782 1783 mrem = vm_radix_remove(&m->object->rtree, m->pindex); 1784 KASSERT(mrem == m, 1785 ("removed page %p, expected page %p", mrem, m)); 1786 } 1787 1788 /* 1789 * vm_page_remove_xbusy 1790 * 1791 * Removes the page but leaves the xbusy held. Returns true if this 1792 * removed the final ref and false otherwise. 1793 */ 1794 bool 1795 vm_page_remove_xbusy(vm_page_t m) 1796 { 1797 1798 vm_page_radix_remove(m); 1799 vm_page_remove_radixdone(m); 1800 return (vm_page_drop(m, VPRC_OBJREF) == VPRC_OBJREF); 1801 } 1802 1803 /* 1804 * vm_page_lookup: 1805 * 1806 * Returns the page associated with the object/offset 1807 * pair specified; if none is found, NULL is returned. 1808 * 1809 * The object must be locked. 1810 */ 1811 vm_page_t 1812 vm_page_lookup(vm_object_t object, vm_pindex_t pindex) 1813 { 1814 1815 VM_OBJECT_ASSERT_LOCKED(object); 1816 return (vm_radix_lookup(&object->rtree, pindex)); 1817 } 1818 1819 /* 1820 * vm_page_iter_init: 1821 * 1822 * Initialize iterator for vm pages. 1823 */ 1824 void 1825 vm_page_iter_init(struct pctrie_iter *pages, vm_object_t object) 1826 { 1827 1828 vm_radix_iter_init(pages, &object->rtree); 1829 } 1830 1831 /* 1832 * vm_page_iter_init: 1833 * 1834 * Initialize iterator for vm pages. 1835 */ 1836 void 1837 vm_page_iter_limit_init(struct pctrie_iter *pages, vm_object_t object, 1838 vm_pindex_t limit) 1839 { 1840 1841 vm_radix_iter_limit_init(pages, &object->rtree, limit); 1842 } 1843 1844 /* 1845 * vm_page_iter_lookup: 1846 * 1847 * Returns the page associated with the object/offset pair specified, and 1848 * stores the path to its position; if none is found, NULL is returned. 1849 * 1850 * The iter pctrie must be locked. 1851 */ 1852 vm_page_t 1853 vm_page_iter_lookup(struct pctrie_iter *pages, vm_pindex_t pindex) 1854 { 1855 1856 return (vm_radix_iter_lookup(pages, pindex)); 1857 } 1858 1859 /* 1860 * vm_page_lookup_unlocked: 1861 * 1862 * Returns the page associated with the object/offset pair specified; 1863 * if none is found, NULL is returned. The page may be no longer be 1864 * present in the object at the time that this function returns. Only 1865 * useful for opportunistic checks such as inmem(). 1866 */ 1867 vm_page_t 1868 vm_page_lookup_unlocked(vm_object_t object, vm_pindex_t pindex) 1869 { 1870 1871 return (vm_radix_lookup_unlocked(&object->rtree, pindex)); 1872 } 1873 1874 /* 1875 * vm_page_relookup: 1876 * 1877 * Returns a page that must already have been busied by 1878 * the caller. Used for bogus page replacement. 1879 */ 1880 vm_page_t 1881 vm_page_relookup(vm_object_t object, vm_pindex_t pindex) 1882 { 1883 vm_page_t m; 1884 1885 m = vm_page_lookup_unlocked(object, pindex); 1886 KASSERT(m != NULL && (vm_page_busied(m) || vm_page_wired(m)) && 1887 m->object == object && m->pindex == pindex, 1888 ("vm_page_relookup: Invalid page %p", m)); 1889 return (m); 1890 } 1891 1892 /* 1893 * This should only be used by lockless functions for releasing transient 1894 * incorrect acquires. The page may have been freed after we acquired a 1895 * busy lock. In this case busy_lock == VPB_FREED and we have nothing 1896 * further to do. 1897 */ 1898 static void 1899 vm_page_busy_release(vm_page_t m) 1900 { 1901 u_int x; 1902 1903 x = vm_page_busy_fetch(m); 1904 for (;;) { 1905 if (x == VPB_FREED) 1906 break; 1907 if ((x & VPB_BIT_SHARED) != 0 && VPB_SHARERS(x) > 1) { 1908 if (atomic_fcmpset_int(&m->busy_lock, &x, 1909 x - VPB_ONE_SHARER)) 1910 break; 1911 continue; 1912 } 1913 KASSERT((x & VPB_BIT_SHARED) != 0 || 1914 (x & ~VPB_BIT_WAITERS) == VPB_CURTHREAD_EXCLUSIVE, 1915 ("vm_page_busy_release: %p xbusy not owned.", m)); 1916 if (!atomic_fcmpset_rel_int(&m->busy_lock, &x, VPB_UNBUSIED)) 1917 continue; 1918 if ((x & VPB_BIT_WAITERS) != 0) 1919 wakeup(m); 1920 break; 1921 } 1922 } 1923 1924 /* 1925 * vm_page_find_least: 1926 * 1927 * Returns the page associated with the object with least pindex 1928 * greater than or equal to the parameter pindex, or NULL. 1929 * 1930 * The object must be locked. 1931 */ 1932 vm_page_t 1933 vm_page_find_least(vm_object_t object, vm_pindex_t pindex) 1934 { 1935 vm_page_t m; 1936 1937 VM_OBJECT_ASSERT_LOCKED(object); 1938 if ((m = TAILQ_FIRST(&object->memq)) != NULL && m->pindex < pindex) 1939 m = vm_radix_lookup_ge(&object->rtree, pindex); 1940 return (m); 1941 } 1942 1943 /* 1944 * vm_page_iter_lookup_ge: 1945 * 1946 * Returns the page associated with the object with least pindex 1947 * greater than or equal to the parameter pindex, or NULL. Initializes the 1948 * iterator to point to that page. 1949 * 1950 * The iter pctrie must be locked. 1951 */ 1952 vm_page_t 1953 vm_page_iter_lookup_ge(struct pctrie_iter *pages, vm_pindex_t pindex) 1954 { 1955 1956 return (vm_radix_iter_lookup_ge(pages, pindex)); 1957 } 1958 1959 /* 1960 * Returns the given page's successor (by pindex) within the object if it is 1961 * resident; if none is found, NULL is returned. 1962 * 1963 * The object must be locked. 1964 */ 1965 vm_page_t 1966 vm_page_next(vm_page_t m) 1967 { 1968 vm_page_t next; 1969 1970 VM_OBJECT_ASSERT_LOCKED(m->object); 1971 if ((next = TAILQ_NEXT(m, listq)) != NULL) { 1972 MPASS(next->object == m->object); 1973 if (next->pindex != m->pindex + 1) 1974 next = NULL; 1975 } 1976 return (next); 1977 } 1978 1979 /* 1980 * Returns the given page's predecessor (by pindex) within the object if it is 1981 * resident; if none is found, NULL is returned. 1982 * 1983 * The object must be locked. 1984 */ 1985 vm_page_t 1986 vm_page_prev(vm_page_t m) 1987 { 1988 vm_page_t prev; 1989 1990 VM_OBJECT_ASSERT_LOCKED(m->object); 1991 if ((prev = TAILQ_PREV(m, pglist, listq)) != NULL) { 1992 MPASS(prev->object == m->object); 1993 if (prev->pindex != m->pindex - 1) 1994 prev = NULL; 1995 } 1996 return (prev); 1997 } 1998 1999 /* 2000 * Uses the page mnew as a replacement for an existing page at index 2001 * pindex which must be already present in the object. 2002 * 2003 * Both pages must be exclusively busied on enter. The old page is 2004 * unbusied on exit. 2005 * 2006 * A return value of true means mold is now free. If this is not the 2007 * final ref and the caller does not hold a wire reference it may not 2008 * continue to access the page. 2009 */ 2010 static bool 2011 vm_page_replace_hold(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex, 2012 vm_page_t mold) 2013 { 2014 vm_page_t mret __diagused; 2015 bool dropped; 2016 2017 VM_OBJECT_ASSERT_WLOCKED(object); 2018 vm_page_assert_xbusied(mold); 2019 KASSERT(mnew->object == NULL && (mnew->ref_count & VPRC_OBJREF) == 0, 2020 ("vm_page_replace: page %p already in object", mnew)); 2021 2022 /* 2023 * This function mostly follows vm_page_insert() and 2024 * vm_page_remove() without the radix, object count and vnode 2025 * dance. Double check such functions for more comments. 2026 */ 2027 2028 mnew->object = object; 2029 mnew->pindex = pindex; 2030 atomic_set_int(&mnew->ref_count, VPRC_OBJREF); 2031 mret = vm_radix_replace(&object->rtree, mnew); 2032 KASSERT(mret == mold, 2033 ("invalid page replacement, mold=%p, mret=%p", mold, mret)); 2034 KASSERT((mold->oflags & VPO_UNMANAGED) == 2035 (mnew->oflags & VPO_UNMANAGED), 2036 ("vm_page_replace: mismatched VPO_UNMANAGED")); 2037 2038 /* Keep the resident page list in sorted order. */ 2039 TAILQ_INSERT_AFTER(&object->memq, mold, mnew, listq); 2040 TAILQ_REMOVE(&object->memq, mold, listq); 2041 mold->object = NULL; 2042 2043 /* 2044 * The object's resident_page_count does not change because we have 2045 * swapped one page for another, but the generation count should 2046 * change if the page is dirty. 2047 */ 2048 if (pmap_page_is_write_mapped(mnew)) 2049 vm_object_set_writeable_dirty(object); 2050 dropped = vm_page_drop(mold, VPRC_OBJREF) == VPRC_OBJREF; 2051 vm_page_xunbusy(mold); 2052 2053 return (dropped); 2054 } 2055 2056 void 2057 vm_page_replace(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex, 2058 vm_page_t mold) 2059 { 2060 2061 vm_page_assert_xbusied(mnew); 2062 2063 if (vm_page_replace_hold(mnew, object, pindex, mold)) 2064 vm_page_free(mold); 2065 } 2066 2067 /* 2068 * vm_page_iter_rename: 2069 * 2070 * Tries to move the specified page from its current object to a new object 2071 * and pindex, using the given iterator to remove the page from its current 2072 * object. Returns true if the move was successful, and false if the move 2073 * was aborted due to a failed memory allocation. 2074 * 2075 * Panics if a page already resides in the new object at the new pindex. 2076 * 2077 * Note: swap associated with the page must be invalidated by the move. We 2078 * have to do this for several reasons: (1) we aren't freeing the 2079 * page, (2) we are dirtying the page, (3) the VM system is probably 2080 * moving the page from object A to B, and will then later move 2081 * the backing store from A to B and we can't have a conflict. 2082 * 2083 * Note: we *always* dirty the page. It is necessary both for the 2084 * fact that we moved it, and because we may be invalidating 2085 * swap. 2086 * 2087 * The objects must be locked. 2088 */ 2089 bool 2090 vm_page_iter_rename(struct pctrie_iter *old_pages, vm_page_t m, 2091 vm_object_t new_object, vm_pindex_t new_pindex) 2092 { 2093 vm_page_t mpred; 2094 vm_pindex_t opidx; 2095 2096 KASSERT((m->ref_count & VPRC_OBJREF) != 0, 2097 ("%s: page %p is missing object ref", __func__, m)); 2098 VM_OBJECT_ASSERT_WLOCKED(m->object); 2099 VM_OBJECT_ASSERT_WLOCKED(new_object); 2100 2101 /* 2102 * Create a custom version of vm_page_insert() which does not depend 2103 * by m_prev and can cheat on the implementation aspects of the 2104 * function. 2105 */ 2106 opidx = m->pindex; 2107 m->pindex = new_pindex; 2108 if (vm_radix_insert_lookup_lt(&new_object->rtree, m, &mpred) != 0) { 2109 m->pindex = opidx; 2110 return (false); 2111 } 2112 2113 /* 2114 * The operation cannot fail anymore. The removal must happen before 2115 * the listq iterator is tainted. 2116 */ 2117 m->pindex = opidx; 2118 vm_radix_iter_remove(old_pages); 2119 vm_page_remove_radixdone(m); 2120 2121 /* Return back to the new pindex to complete vm_page_insert(). */ 2122 m->pindex = new_pindex; 2123 m->object = new_object; 2124 2125 vm_page_insert_radixdone(m, new_object, mpred); 2126 vm_page_dirty(m); 2127 vm_pager_page_inserted(new_object, m); 2128 return (true); 2129 } 2130 2131 /* 2132 * vm_page_mpred: 2133 * 2134 * Return the greatest page of the object with index <= pindex, 2135 * or NULL, if there is none. Assumes object lock is held. 2136 */ 2137 vm_page_t 2138 vm_page_mpred(vm_object_t object, vm_pindex_t pindex) 2139 { 2140 return (vm_radix_lookup_le(&object->rtree, pindex)); 2141 } 2142 2143 /* 2144 * vm_page_alloc: 2145 * 2146 * Allocate and return a page that is associated with the specified 2147 * object and offset pair. By default, this page is exclusive busied. 2148 * 2149 * The caller must always specify an allocation class. 2150 * 2151 * allocation classes: 2152 * VM_ALLOC_NORMAL normal process request 2153 * VM_ALLOC_SYSTEM system *really* needs a page 2154 * VM_ALLOC_INTERRUPT interrupt time request 2155 * 2156 * optional allocation flags: 2157 * VM_ALLOC_COUNT(number) the number of additional pages that the caller 2158 * intends to allocate 2159 * VM_ALLOC_NOBUSY do not exclusive busy the page 2160 * VM_ALLOC_NODUMP do not include the page in a kernel core dump 2161 * VM_ALLOC_SBUSY shared busy the allocated page 2162 * VM_ALLOC_WIRED wire the allocated page 2163 * VM_ALLOC_ZERO prefer a zeroed page 2164 */ 2165 vm_page_t 2166 vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req) 2167 { 2168 2169 return (vm_page_alloc_after(object, pindex, req, 2170 vm_page_mpred(object, pindex))); 2171 } 2172 2173 /* 2174 * Allocate a page in the specified object with the given page index. To 2175 * optimize insertion of the page into the object, the caller must also specify 2176 * the resident page in the object with largest index smaller than the given 2177 * page index, or NULL if no such page exists. 2178 */ 2179 static vm_page_t 2180 vm_page_alloc_after(vm_object_t object, vm_pindex_t pindex, 2181 int req, vm_page_t mpred) 2182 { 2183 struct vm_domainset_iter di; 2184 vm_page_t m; 2185 int domain; 2186 2187 vm_domainset_iter_page_init(&di, object, pindex, &domain, &req); 2188 do { 2189 m = vm_page_alloc_domain_after(object, pindex, domain, req, 2190 mpred); 2191 if (m != NULL) 2192 break; 2193 } while (vm_domainset_iter_page(&di, object, &domain) == 0); 2194 2195 return (m); 2196 } 2197 2198 /* 2199 * Returns true if the number of free pages exceeds the minimum 2200 * for the request class and false otherwise. 2201 */ 2202 static int 2203 _vm_domain_allocate(struct vm_domain *vmd, int req_class, int npages) 2204 { 2205 u_int limit, old, new; 2206 2207 if (req_class == VM_ALLOC_INTERRUPT) 2208 limit = 0; 2209 else if (req_class == VM_ALLOC_SYSTEM) 2210 limit = vmd->vmd_interrupt_free_min; 2211 else 2212 limit = vmd->vmd_free_reserved; 2213 2214 /* 2215 * Attempt to reserve the pages. Fail if we're below the limit. 2216 */ 2217 limit += npages; 2218 old = atomic_load_int(&vmd->vmd_free_count); 2219 do { 2220 if (old < limit) 2221 return (0); 2222 new = old - npages; 2223 } while (atomic_fcmpset_int(&vmd->vmd_free_count, &old, new) == 0); 2224 2225 /* Wake the page daemon if we've crossed the threshold. */ 2226 if (vm_paging_needed(vmd, new) && !vm_paging_needed(vmd, old)) 2227 pagedaemon_wakeup(vmd->vmd_domain); 2228 2229 /* Only update bitsets on transitions. */ 2230 if ((old >= vmd->vmd_free_min && new < vmd->vmd_free_min) || 2231 (old >= vmd->vmd_free_severe && new < vmd->vmd_free_severe)) 2232 vm_domain_set(vmd); 2233 2234 return (1); 2235 } 2236 2237 int 2238 vm_domain_allocate(struct vm_domain *vmd, int req, int npages) 2239 { 2240 int req_class; 2241 2242 /* 2243 * The page daemon is allowed to dig deeper into the free page list. 2244 */ 2245 req_class = req & VM_ALLOC_CLASS_MASK; 2246 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 2247 req_class = VM_ALLOC_SYSTEM; 2248 return (_vm_domain_allocate(vmd, req_class, npages)); 2249 } 2250 2251 vm_page_t 2252 vm_page_alloc_domain_after(vm_object_t object, vm_pindex_t pindex, int domain, 2253 int req, vm_page_t mpred) 2254 { 2255 struct vm_domain *vmd; 2256 vm_page_t m; 2257 int flags; 2258 2259 #define VPA_FLAGS (VM_ALLOC_CLASS_MASK | VM_ALLOC_WAITFAIL | \ 2260 VM_ALLOC_NOWAIT | VM_ALLOC_NOBUSY | \ 2261 VM_ALLOC_SBUSY | VM_ALLOC_WIRED | \ 2262 VM_ALLOC_NODUMP | VM_ALLOC_ZERO | \ 2263 VM_ALLOC_NOFREE | VM_ALLOC_COUNT_MASK) 2264 KASSERT((req & ~VPA_FLAGS) == 0, 2265 ("invalid request %#x", req)); 2266 KASSERT(((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 2267 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 2268 ("invalid request %#x", req)); 2269 KASSERT(mpred == NULL || mpred->pindex < pindex, 2270 ("mpred %p doesn't precede pindex 0x%jx", mpred, 2271 (uintmax_t)pindex)); 2272 VM_OBJECT_ASSERT_WLOCKED(object); 2273 2274 flags = 0; 2275 m = NULL; 2276 if (!vm_pager_can_alloc_page(object, pindex)) 2277 return (NULL); 2278 again: 2279 if (__predict_false((req & VM_ALLOC_NOFREE) != 0)) { 2280 m = vm_page_alloc_nofree_domain(domain, req); 2281 if (m != NULL) 2282 goto found; 2283 } 2284 #if VM_NRESERVLEVEL > 0 2285 /* 2286 * Can we allocate the page from a reservation? 2287 */ 2288 if (vm_object_reserv(object) && 2289 (m = vm_reserv_alloc_page(object, pindex, domain, req, mpred)) != 2290 NULL) { 2291 goto found; 2292 } 2293 #endif 2294 vmd = VM_DOMAIN(domain); 2295 if (vmd->vmd_pgcache[VM_FREEPOOL_DEFAULT].zone != NULL) { 2296 m = uma_zalloc(vmd->vmd_pgcache[VM_FREEPOOL_DEFAULT].zone, 2297 M_NOWAIT | M_NOVM); 2298 if (m != NULL) { 2299 flags |= PG_PCPU_CACHE; 2300 goto found; 2301 } 2302 } 2303 if (vm_domain_allocate(vmd, req, 1)) { 2304 /* 2305 * If not, allocate it from the free page queues. 2306 */ 2307 vm_domain_free_lock(vmd); 2308 m = vm_phys_alloc_pages(domain, VM_FREEPOOL_DEFAULT, 0); 2309 vm_domain_free_unlock(vmd); 2310 if (m == NULL) { 2311 vm_domain_freecnt_inc(vmd, 1); 2312 #if VM_NRESERVLEVEL > 0 2313 if (vm_reserv_reclaim_inactive(domain)) 2314 goto again; 2315 #endif 2316 } 2317 } 2318 if (m == NULL) { 2319 /* 2320 * Not allocatable, give up. 2321 */ 2322 if (vm_domain_alloc_fail(vmd, object, req)) 2323 goto again; 2324 return (NULL); 2325 } 2326 2327 /* 2328 * At this point we had better have found a good page. 2329 */ 2330 found: 2331 vm_page_dequeue(m); 2332 vm_page_alloc_check(m); 2333 2334 /* 2335 * Initialize the page. Only the PG_ZERO flag is inherited. 2336 */ 2337 flags |= m->flags & PG_ZERO; 2338 if ((req & VM_ALLOC_NODUMP) != 0) 2339 flags |= PG_NODUMP; 2340 if ((req & VM_ALLOC_NOFREE) != 0) 2341 flags |= PG_NOFREE; 2342 m->flags = flags; 2343 m->a.flags = 0; 2344 m->oflags = (object->flags & OBJ_UNMANAGED) != 0 ? VPO_UNMANAGED : 0; 2345 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0) 2346 m->busy_lock = VPB_CURTHREAD_EXCLUSIVE; 2347 else if ((req & VM_ALLOC_SBUSY) != 0) 2348 m->busy_lock = VPB_SHARERS_WORD(1); 2349 else 2350 m->busy_lock = VPB_UNBUSIED; 2351 if (req & VM_ALLOC_WIRED) { 2352 vm_wire_add(1); 2353 m->ref_count = 1; 2354 } 2355 m->a.act_count = 0; 2356 2357 if (vm_page_insert_after(m, object, pindex, mpred)) { 2358 if (req & VM_ALLOC_WIRED) { 2359 vm_wire_sub(1); 2360 m->ref_count = 0; 2361 } 2362 KASSERT(m->object == NULL, ("page %p has object", m)); 2363 m->oflags = VPO_UNMANAGED; 2364 m->busy_lock = VPB_UNBUSIED; 2365 /* Don't change PG_ZERO. */ 2366 vm_page_free_toq(m); 2367 if (req & VM_ALLOC_WAITFAIL) { 2368 VM_OBJECT_WUNLOCK(object); 2369 vm_radix_wait(); 2370 VM_OBJECT_WLOCK(object); 2371 } 2372 return (NULL); 2373 } 2374 2375 /* Ignore device objects; the pager sets "memattr" for them. */ 2376 if (object->memattr != VM_MEMATTR_DEFAULT && 2377 (object->flags & OBJ_FICTITIOUS) == 0) 2378 pmap_page_set_memattr(m, object->memattr); 2379 2380 return (m); 2381 } 2382 2383 /* 2384 * vm_page_alloc_contig: 2385 * 2386 * Allocate a contiguous set of physical pages of the given size "npages" 2387 * from the free lists. All of the physical pages must be at or above 2388 * the given physical address "low" and below the given physical address 2389 * "high". The given value "alignment" determines the alignment of the 2390 * first physical page in the set. If the given value "boundary" is 2391 * non-zero, then the set of physical pages cannot cross any physical 2392 * address boundary that is a multiple of that value. Both "alignment" 2393 * and "boundary" must be a power of two. 2394 * 2395 * If the specified memory attribute, "memattr", is VM_MEMATTR_DEFAULT, 2396 * then the memory attribute setting for the physical pages is configured 2397 * to the object's memory attribute setting. Otherwise, the memory 2398 * attribute setting for the physical pages is configured to "memattr", 2399 * overriding the object's memory attribute setting. However, if the 2400 * object's memory attribute setting is not VM_MEMATTR_DEFAULT, then the 2401 * memory attribute setting for the physical pages cannot be configured 2402 * to VM_MEMATTR_DEFAULT. 2403 * 2404 * The specified object may not contain fictitious pages. 2405 * 2406 * The caller must always specify an allocation class. 2407 * 2408 * allocation classes: 2409 * VM_ALLOC_NORMAL normal process request 2410 * VM_ALLOC_SYSTEM system *really* needs a page 2411 * VM_ALLOC_INTERRUPT interrupt time request 2412 * 2413 * optional allocation flags: 2414 * VM_ALLOC_NOBUSY do not exclusive busy the page 2415 * VM_ALLOC_NODUMP do not include the page in a kernel core dump 2416 * VM_ALLOC_SBUSY shared busy the allocated page 2417 * VM_ALLOC_WIRED wire the allocated page 2418 * VM_ALLOC_ZERO prefer a zeroed page 2419 */ 2420 vm_page_t 2421 vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req, 2422 u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, 2423 vm_paddr_t boundary, vm_memattr_t memattr) 2424 { 2425 struct vm_domainset_iter di; 2426 vm_page_t bounds[2]; 2427 vm_page_t m; 2428 int domain; 2429 int start_segind; 2430 2431 start_segind = -1; 2432 2433 vm_domainset_iter_page_init(&di, object, pindex, &domain, &req); 2434 do { 2435 m = vm_page_alloc_contig_domain(object, pindex, domain, req, 2436 npages, low, high, alignment, boundary, memattr); 2437 if (m != NULL) 2438 break; 2439 if (start_segind == -1) 2440 start_segind = vm_phys_lookup_segind(low); 2441 if (vm_phys_find_range(bounds, start_segind, domain, 2442 npages, low, high) == -1) { 2443 vm_domainset_iter_ignore(&di, domain); 2444 } 2445 } while (vm_domainset_iter_page(&di, object, &domain) == 0); 2446 2447 return (m); 2448 } 2449 2450 static vm_page_t 2451 vm_page_find_contig_domain(int domain, int req, u_long npages, vm_paddr_t low, 2452 vm_paddr_t high, u_long alignment, vm_paddr_t boundary) 2453 { 2454 struct vm_domain *vmd; 2455 vm_page_t m_ret; 2456 2457 /* 2458 * Can we allocate the pages without the number of free pages falling 2459 * below the lower bound for the allocation class? 2460 */ 2461 vmd = VM_DOMAIN(domain); 2462 if (!vm_domain_allocate(vmd, req, npages)) 2463 return (NULL); 2464 /* 2465 * Try to allocate the pages from the free page queues. 2466 */ 2467 vm_domain_free_lock(vmd); 2468 m_ret = vm_phys_alloc_contig(domain, npages, low, high, 2469 alignment, boundary); 2470 vm_domain_free_unlock(vmd); 2471 if (m_ret != NULL) 2472 return (m_ret); 2473 #if VM_NRESERVLEVEL > 0 2474 /* 2475 * Try to break a reservation to allocate the pages. 2476 */ 2477 if ((req & VM_ALLOC_NORECLAIM) == 0) { 2478 m_ret = vm_reserv_reclaim_contig(domain, npages, low, 2479 high, alignment, boundary); 2480 if (m_ret != NULL) 2481 return (m_ret); 2482 } 2483 #endif 2484 vm_domain_freecnt_inc(vmd, npages); 2485 return (NULL); 2486 } 2487 2488 vm_page_t 2489 vm_page_alloc_contig_domain(vm_object_t object, vm_pindex_t pindex, int domain, 2490 int req, u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, 2491 vm_paddr_t boundary, vm_memattr_t memattr) 2492 { 2493 struct pctrie_iter pages; 2494 vm_page_t m, m_ret, mpred; 2495 u_int busy_lock, flags, oflags; 2496 2497 #define VPAC_FLAGS (VPA_FLAGS | VM_ALLOC_NORECLAIM) 2498 KASSERT((req & ~VPAC_FLAGS) == 0, 2499 ("invalid request %#x", req)); 2500 KASSERT(((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 2501 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 2502 ("invalid request %#x", req)); 2503 KASSERT((req & (VM_ALLOC_WAITOK | VM_ALLOC_NORECLAIM)) != 2504 (VM_ALLOC_WAITOK | VM_ALLOC_NORECLAIM), 2505 ("invalid request %#x", req)); 2506 VM_OBJECT_ASSERT_WLOCKED(object); 2507 KASSERT((object->flags & OBJ_FICTITIOUS) == 0, 2508 ("vm_page_alloc_contig: object %p has fictitious pages", 2509 object)); 2510 KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero")); 2511 2512 vm_page_iter_init(&pages, object); 2513 mpred = vm_radix_iter_lookup_le(&pages, pindex); 2514 KASSERT(mpred == NULL || mpred->pindex != pindex, 2515 ("vm_page_alloc_contig: pindex already allocated")); 2516 for (;;) { 2517 #if VM_NRESERVLEVEL > 0 2518 /* 2519 * Can we allocate the pages from a reservation? 2520 */ 2521 if (vm_object_reserv(object) && 2522 (m_ret = vm_reserv_alloc_contig(object, pindex, domain, req, 2523 mpred, npages, low, high, alignment, boundary)) != NULL) { 2524 break; 2525 } 2526 #endif 2527 if ((m_ret = vm_page_find_contig_domain(domain, req, npages, 2528 low, high, alignment, boundary)) != NULL) 2529 break; 2530 if (!vm_domain_alloc_fail(VM_DOMAIN(domain), object, req)) 2531 return (NULL); 2532 } 2533 2534 /* 2535 * Initialize the pages. Only the PG_ZERO flag is inherited. 2536 */ 2537 flags = PG_ZERO; 2538 if ((req & VM_ALLOC_NODUMP) != 0) 2539 flags |= PG_NODUMP; 2540 oflags = (object->flags & OBJ_UNMANAGED) != 0 ? VPO_UNMANAGED : 0; 2541 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0) 2542 busy_lock = VPB_CURTHREAD_EXCLUSIVE; 2543 else if ((req & VM_ALLOC_SBUSY) != 0) 2544 busy_lock = VPB_SHARERS_WORD(1); 2545 else 2546 busy_lock = VPB_UNBUSIED; 2547 if ((req & VM_ALLOC_WIRED) != 0) 2548 vm_wire_add(npages); 2549 if (object->memattr != VM_MEMATTR_DEFAULT && 2550 memattr == VM_MEMATTR_DEFAULT) 2551 memattr = object->memattr; 2552 for (m = m_ret; m < &m_ret[npages]; m++) { 2553 vm_page_dequeue(m); 2554 vm_page_alloc_check(m); 2555 m->a.flags = 0; 2556 m->flags = (m->flags | PG_NODUMP) & flags; 2557 m->busy_lock = busy_lock; 2558 if ((req & VM_ALLOC_WIRED) != 0) 2559 m->ref_count = 1; 2560 m->a.act_count = 0; 2561 m->oflags = oflags; 2562 if (vm_page_iter_insert(&pages, m, object, pindex, mpred)) { 2563 if ((req & VM_ALLOC_WIRED) != 0) 2564 vm_wire_sub(npages); 2565 KASSERT(m->object == NULL, 2566 ("page %p has object", m)); 2567 mpred = m; 2568 for (m = m_ret; m < &m_ret[npages]; m++) { 2569 if (m <= mpred && 2570 (req & VM_ALLOC_WIRED) != 0) 2571 m->ref_count = 0; 2572 m->oflags = VPO_UNMANAGED; 2573 m->busy_lock = VPB_UNBUSIED; 2574 /* Don't change PG_ZERO. */ 2575 vm_page_free_toq(m); 2576 } 2577 if (req & VM_ALLOC_WAITFAIL) { 2578 VM_OBJECT_WUNLOCK(object); 2579 vm_radix_wait(); 2580 VM_OBJECT_WLOCK(object); 2581 } 2582 return (NULL); 2583 } 2584 mpred = m; 2585 if (memattr != VM_MEMATTR_DEFAULT) 2586 pmap_page_set_memattr(m, memattr); 2587 pindex++; 2588 } 2589 return (m_ret); 2590 } 2591 2592 /* 2593 * Allocate a physical page that is not intended to be inserted into a VM 2594 * object. 2595 */ 2596 vm_page_t 2597 vm_page_alloc_noobj_domain(int domain, int req) 2598 { 2599 struct vm_domain *vmd; 2600 vm_page_t m; 2601 int flags; 2602 2603 #define VPAN_FLAGS (VM_ALLOC_CLASS_MASK | VM_ALLOC_WAITFAIL | \ 2604 VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | \ 2605 VM_ALLOC_NOBUSY | VM_ALLOC_WIRED | \ 2606 VM_ALLOC_NODUMP | VM_ALLOC_ZERO | \ 2607 VM_ALLOC_NOFREE | VM_ALLOC_COUNT_MASK) 2608 KASSERT((req & ~VPAN_FLAGS) == 0, 2609 ("invalid request %#x", req)); 2610 2611 flags = ((req & VM_ALLOC_NODUMP) != 0 ? PG_NODUMP : 0) | 2612 ((req & VM_ALLOC_NOFREE) != 0 ? PG_NOFREE : 0); 2613 vmd = VM_DOMAIN(domain); 2614 again: 2615 if (__predict_false((req & VM_ALLOC_NOFREE) != 0)) { 2616 m = vm_page_alloc_nofree_domain(domain, req); 2617 if (m != NULL) 2618 goto found; 2619 } 2620 2621 if (vmd->vmd_pgcache[VM_FREEPOOL_DIRECT].zone != NULL) { 2622 m = uma_zalloc(vmd->vmd_pgcache[VM_FREEPOOL_DIRECT].zone, 2623 M_NOWAIT | M_NOVM); 2624 if (m != NULL) { 2625 flags |= PG_PCPU_CACHE; 2626 goto found; 2627 } 2628 } 2629 2630 if (vm_domain_allocate(vmd, req, 1)) { 2631 vm_domain_free_lock(vmd); 2632 m = vm_phys_alloc_pages(domain, VM_FREEPOOL_DIRECT, 0); 2633 vm_domain_free_unlock(vmd); 2634 if (m == NULL) { 2635 vm_domain_freecnt_inc(vmd, 1); 2636 #if VM_NRESERVLEVEL > 0 2637 if (vm_reserv_reclaim_inactive(domain)) 2638 goto again; 2639 #endif 2640 } 2641 } 2642 if (m == NULL) { 2643 if (vm_domain_alloc_fail(vmd, NULL, req)) 2644 goto again; 2645 return (NULL); 2646 } 2647 2648 found: 2649 vm_page_dequeue(m); 2650 vm_page_alloc_check(m); 2651 2652 /* 2653 * Consumers should not rely on a useful default pindex value. 2654 */ 2655 m->pindex = 0xdeadc0dedeadc0de; 2656 m->flags = (m->flags & PG_ZERO) | flags; 2657 m->a.flags = 0; 2658 m->oflags = VPO_UNMANAGED; 2659 m->busy_lock = VPB_UNBUSIED; 2660 if ((req & VM_ALLOC_WIRED) != 0) { 2661 vm_wire_add(1); 2662 m->ref_count = 1; 2663 } 2664 2665 if ((req & VM_ALLOC_ZERO) != 0 && (m->flags & PG_ZERO) == 0) 2666 pmap_zero_page(m); 2667 2668 return (m); 2669 } 2670 2671 #if VM_NRESERVLEVEL > 1 2672 #define VM_NOFREE_IMPORT_ORDER (VM_LEVEL_1_ORDER + VM_LEVEL_0_ORDER) 2673 #elif VM_NRESERVLEVEL > 0 2674 #define VM_NOFREE_IMPORT_ORDER VM_LEVEL_0_ORDER 2675 #else 2676 #define VM_NOFREE_IMPORT_ORDER 8 2677 #endif 2678 2679 /* 2680 * Allocate a single NOFREE page. 2681 * 2682 * This routine hands out NOFREE pages from higher-order 2683 * physical memory blocks in order to reduce memory fragmentation. 2684 * When a NOFREE for a given domain chunk is used up, 2685 * the routine will try to fetch a new one from the freelists 2686 * and discard the old one. 2687 */ 2688 static vm_page_t 2689 vm_page_alloc_nofree_domain(int domain, int req) 2690 { 2691 vm_page_t m; 2692 struct vm_domain *vmd; 2693 struct vm_nofreeq *nqp; 2694 2695 KASSERT((req & VM_ALLOC_NOFREE) != 0, ("invalid request %#x", req)); 2696 2697 vmd = VM_DOMAIN(domain); 2698 nqp = &vmd->vmd_nofreeq; 2699 vm_domain_free_lock(vmd); 2700 if (nqp->offs >= (1 << VM_NOFREE_IMPORT_ORDER) || nqp->ma == NULL) { 2701 if (!vm_domain_allocate(vmd, req, 2702 1 << VM_NOFREE_IMPORT_ORDER)) { 2703 vm_domain_free_unlock(vmd); 2704 return (NULL); 2705 } 2706 nqp->ma = vm_phys_alloc_pages(domain, VM_FREEPOOL_DEFAULT, 2707 VM_NOFREE_IMPORT_ORDER); 2708 if (nqp->ma == NULL) { 2709 vm_domain_freecnt_inc(vmd, 1 << VM_NOFREE_IMPORT_ORDER); 2710 vm_domain_free_unlock(vmd); 2711 return (NULL); 2712 } 2713 nqp->offs = 0; 2714 } 2715 m = &nqp->ma[nqp->offs++]; 2716 vm_domain_free_unlock(vmd); 2717 VM_CNT_ADD(v_nofree_count, 1); 2718 2719 return (m); 2720 } 2721 2722 vm_page_t 2723 vm_page_alloc_noobj(int req) 2724 { 2725 struct vm_domainset_iter di; 2726 vm_page_t m; 2727 int domain; 2728 2729 vm_domainset_iter_page_init(&di, NULL, 0, &domain, &req); 2730 do { 2731 m = vm_page_alloc_noobj_domain(domain, req); 2732 if (m != NULL) 2733 break; 2734 } while (vm_domainset_iter_page(&di, NULL, &domain) == 0); 2735 2736 return (m); 2737 } 2738 2739 vm_page_t 2740 vm_page_alloc_noobj_contig(int req, u_long npages, vm_paddr_t low, 2741 vm_paddr_t high, u_long alignment, vm_paddr_t boundary, 2742 vm_memattr_t memattr) 2743 { 2744 struct vm_domainset_iter di; 2745 vm_page_t m; 2746 int domain; 2747 2748 vm_domainset_iter_page_init(&di, NULL, 0, &domain, &req); 2749 do { 2750 m = vm_page_alloc_noobj_contig_domain(domain, req, npages, low, 2751 high, alignment, boundary, memattr); 2752 if (m != NULL) 2753 break; 2754 } while (vm_domainset_iter_page(&di, NULL, &domain) == 0); 2755 2756 return (m); 2757 } 2758 2759 vm_page_t 2760 vm_page_alloc_noobj_contig_domain(int domain, int req, u_long npages, 2761 vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary, 2762 vm_memattr_t memattr) 2763 { 2764 vm_page_t m, m_ret; 2765 u_int flags; 2766 2767 #define VPANC_FLAGS (VPAN_FLAGS | VM_ALLOC_NORECLAIM) 2768 KASSERT((req & ~VPANC_FLAGS) == 0, 2769 ("invalid request %#x", req)); 2770 KASSERT((req & (VM_ALLOC_WAITOK | VM_ALLOC_NORECLAIM)) != 2771 (VM_ALLOC_WAITOK | VM_ALLOC_NORECLAIM), 2772 ("invalid request %#x", req)); 2773 KASSERT(((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 2774 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 2775 ("invalid request %#x", req)); 2776 KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero")); 2777 2778 while ((m_ret = vm_page_find_contig_domain(domain, req, npages, 2779 low, high, alignment, boundary)) == NULL) { 2780 if (!vm_domain_alloc_fail(VM_DOMAIN(domain), NULL, req)) 2781 return (NULL); 2782 } 2783 2784 /* 2785 * Initialize the pages. Only the PG_ZERO flag is inherited. 2786 */ 2787 flags = PG_ZERO; 2788 if ((req & VM_ALLOC_NODUMP) != 0) 2789 flags |= PG_NODUMP; 2790 if ((req & VM_ALLOC_WIRED) != 0) 2791 vm_wire_add(npages); 2792 for (m = m_ret; m < &m_ret[npages]; m++) { 2793 vm_page_dequeue(m); 2794 vm_page_alloc_check(m); 2795 2796 /* 2797 * Consumers should not rely on a useful default pindex value. 2798 */ 2799 m->pindex = 0xdeadc0dedeadc0de; 2800 m->a.flags = 0; 2801 m->flags = (m->flags | PG_NODUMP) & flags; 2802 m->busy_lock = VPB_UNBUSIED; 2803 if ((req & VM_ALLOC_WIRED) != 0) 2804 m->ref_count = 1; 2805 m->a.act_count = 0; 2806 m->oflags = VPO_UNMANAGED; 2807 2808 /* 2809 * Zero the page before updating any mappings since the page is 2810 * not yet shared with any devices which might require the 2811 * non-default memory attribute. pmap_page_set_memattr() 2812 * flushes data caches before returning. 2813 */ 2814 if ((req & VM_ALLOC_ZERO) != 0 && (m->flags & PG_ZERO) == 0) 2815 pmap_zero_page(m); 2816 if (memattr != VM_MEMATTR_DEFAULT) 2817 pmap_page_set_memattr(m, memattr); 2818 } 2819 return (m_ret); 2820 } 2821 2822 /* 2823 * Check a page that has been freshly dequeued from a freelist. 2824 */ 2825 static void 2826 vm_page_alloc_check(vm_page_t m) 2827 { 2828 2829 KASSERT(m->object == NULL, ("page %p has object", m)); 2830 KASSERT(m->a.queue == PQ_NONE && 2831 (m->a.flags & PGA_QUEUE_STATE_MASK) == 0, 2832 ("page %p has unexpected queue %d, flags %#x", 2833 m, m->a.queue, (m->a.flags & PGA_QUEUE_STATE_MASK))); 2834 KASSERT(m->ref_count == 0, ("page %p has references", m)); 2835 KASSERT(vm_page_busy_freed(m), ("page %p is not freed", m)); 2836 KASSERT(m->dirty == 0, ("page %p is dirty", m)); 2837 KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, 2838 ("page %p has unexpected memattr %d", 2839 m, pmap_page_get_memattr(m))); 2840 KASSERT(vm_page_none_valid(m), ("free page %p is valid", m)); 2841 pmap_vm_page_alloc_check(m); 2842 } 2843 2844 static int 2845 vm_page_zone_import(void *arg, void **store, int cnt, int domain, int flags) 2846 { 2847 struct vm_domain *vmd; 2848 struct vm_pgcache *pgcache; 2849 int i; 2850 2851 pgcache = arg; 2852 vmd = VM_DOMAIN(pgcache->domain); 2853 2854 /* 2855 * The page daemon should avoid creating extra memory pressure since its 2856 * main purpose is to replenish the store of free pages. 2857 */ 2858 if (vmd->vmd_severeset || curproc == pageproc || 2859 !_vm_domain_allocate(vmd, VM_ALLOC_NORMAL, cnt)) 2860 return (0); 2861 domain = vmd->vmd_domain; 2862 vm_domain_free_lock(vmd); 2863 i = vm_phys_alloc_npages(domain, pgcache->pool, cnt, 2864 (vm_page_t *)store); 2865 vm_domain_free_unlock(vmd); 2866 if (cnt != i) 2867 vm_domain_freecnt_inc(vmd, cnt - i); 2868 2869 return (i); 2870 } 2871 2872 static void 2873 vm_page_zone_release(void *arg, void **store, int cnt) 2874 { 2875 struct vm_domain *vmd; 2876 struct vm_pgcache *pgcache; 2877 vm_page_t m; 2878 int i; 2879 2880 pgcache = arg; 2881 vmd = VM_DOMAIN(pgcache->domain); 2882 vm_domain_free_lock(vmd); 2883 for (i = 0; i < cnt; i++) { 2884 m = (vm_page_t)store[i]; 2885 vm_phys_free_pages(m, 0); 2886 } 2887 vm_domain_free_unlock(vmd); 2888 vm_domain_freecnt_inc(vmd, cnt); 2889 } 2890 2891 #define VPSC_ANY 0 /* No restrictions. */ 2892 #define VPSC_NORESERV 1 /* Skip reservations; implies VPSC_NOSUPER. */ 2893 #define VPSC_NOSUPER 2 /* Skip superpages. */ 2894 2895 /* 2896 * vm_page_scan_contig: 2897 * 2898 * Scan vm_page_array[] between the specified entries "m_start" and 2899 * "m_end" for a run of contiguous physical pages that satisfy the 2900 * specified conditions, and return the lowest page in the run. The 2901 * specified "alignment" determines the alignment of the lowest physical 2902 * page in the run. If the specified "boundary" is non-zero, then the 2903 * run of physical pages cannot span a physical address that is a 2904 * multiple of "boundary". 2905 * 2906 * "m_end" is never dereferenced, so it need not point to a vm_page 2907 * structure within vm_page_array[]. 2908 * 2909 * "npages" must be greater than zero. "m_start" and "m_end" must not 2910 * span a hole (or discontiguity) in the physical address space. Both 2911 * "alignment" and "boundary" must be a power of two. 2912 */ 2913 static vm_page_t 2914 vm_page_scan_contig(u_long npages, vm_page_t m_start, vm_page_t m_end, 2915 u_long alignment, vm_paddr_t boundary, int options) 2916 { 2917 vm_object_t object; 2918 vm_paddr_t pa; 2919 vm_page_t m, m_run; 2920 #if VM_NRESERVLEVEL > 0 2921 int level; 2922 #endif 2923 int m_inc, order, run_ext, run_len; 2924 2925 KASSERT(npages > 0, ("npages is 0")); 2926 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 2927 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 2928 m_run = NULL; 2929 run_len = 0; 2930 for (m = m_start; m < m_end && run_len < npages; m += m_inc) { 2931 KASSERT((m->flags & PG_MARKER) == 0, 2932 ("page %p is PG_MARKER", m)); 2933 KASSERT((m->flags & PG_FICTITIOUS) == 0 || m->ref_count >= 1, 2934 ("fictitious page %p has invalid ref count", m)); 2935 2936 /* 2937 * If the current page would be the start of a run, check its 2938 * physical address against the end, alignment, and boundary 2939 * conditions. If it doesn't satisfy these conditions, either 2940 * terminate the scan or advance to the next page that 2941 * satisfies the failed condition. 2942 */ 2943 if (run_len == 0) { 2944 KASSERT(m_run == NULL, ("m_run != NULL")); 2945 if (m + npages > m_end) 2946 break; 2947 pa = VM_PAGE_TO_PHYS(m); 2948 if (!vm_addr_align_ok(pa, alignment)) { 2949 m_inc = atop(roundup2(pa, alignment) - pa); 2950 continue; 2951 } 2952 if (!vm_addr_bound_ok(pa, ptoa(npages), boundary)) { 2953 m_inc = atop(roundup2(pa, boundary) - pa); 2954 continue; 2955 } 2956 } else 2957 KASSERT(m_run != NULL, ("m_run == NULL")); 2958 2959 retry: 2960 m_inc = 1; 2961 if (vm_page_wired(m)) 2962 run_ext = 0; 2963 #if VM_NRESERVLEVEL > 0 2964 else if ((level = vm_reserv_level(m)) >= 0 && 2965 (options & VPSC_NORESERV) != 0) { 2966 run_ext = 0; 2967 /* Advance to the end of the reservation. */ 2968 pa = VM_PAGE_TO_PHYS(m); 2969 m_inc = atop(roundup2(pa + 1, vm_reserv_size(level)) - 2970 pa); 2971 } 2972 #endif 2973 else if ((object = atomic_load_ptr(&m->object)) != NULL) { 2974 /* 2975 * The page is considered eligible for relocation if 2976 * and only if it could be laundered or reclaimed by 2977 * the page daemon. 2978 */ 2979 VM_OBJECT_RLOCK(object); 2980 if (object != m->object) { 2981 VM_OBJECT_RUNLOCK(object); 2982 goto retry; 2983 } 2984 /* Don't care: PG_NODUMP, PG_ZERO. */ 2985 if ((object->flags & OBJ_SWAP) == 0 && 2986 object->type != OBJT_VNODE) { 2987 run_ext = 0; 2988 #if VM_NRESERVLEVEL > 0 2989 } else if ((options & VPSC_NOSUPER) != 0 && 2990 (level = vm_reserv_level_iffullpop(m)) >= 0) { 2991 run_ext = 0; 2992 /* Advance to the end of the superpage. */ 2993 pa = VM_PAGE_TO_PHYS(m); 2994 m_inc = atop(roundup2(pa + 1, 2995 vm_reserv_size(level)) - pa); 2996 #endif 2997 } else if (object->memattr == VM_MEMATTR_DEFAULT && 2998 vm_page_queue(m) != PQ_NONE && !vm_page_busied(m)) { 2999 /* 3000 * The page is allocated but eligible for 3001 * relocation. Extend the current run by one 3002 * page. 3003 */ 3004 KASSERT(pmap_page_get_memattr(m) == 3005 VM_MEMATTR_DEFAULT, 3006 ("page %p has an unexpected memattr", m)); 3007 KASSERT((m->oflags & (VPO_SWAPINPROG | 3008 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, 3009 ("page %p has unexpected oflags", m)); 3010 /* Don't care: PGA_NOSYNC. */ 3011 run_ext = 1; 3012 } else 3013 run_ext = 0; 3014 VM_OBJECT_RUNLOCK(object); 3015 #if VM_NRESERVLEVEL > 0 3016 } else if (level >= 0) { 3017 /* 3018 * The page is reserved but not yet allocated. In 3019 * other words, it is still free. Extend the current 3020 * run by one page. 3021 */ 3022 run_ext = 1; 3023 #endif 3024 } else if ((order = m->order) < VM_NFREEORDER) { 3025 /* 3026 * The page is enqueued in the physical memory 3027 * allocator's free page queues. Moreover, it is the 3028 * first page in a power-of-two-sized run of 3029 * contiguous free pages. Add these pages to the end 3030 * of the current run, and jump ahead. 3031 */ 3032 run_ext = 1 << order; 3033 m_inc = 1 << order; 3034 } else { 3035 /* 3036 * Skip the page for one of the following reasons: (1) 3037 * It is enqueued in the physical memory allocator's 3038 * free page queues. However, it is not the first 3039 * page in a run of contiguous free pages. (This case 3040 * rarely occurs because the scan is performed in 3041 * ascending order.) (2) It is not reserved, and it is 3042 * transitioning from free to allocated. (Conversely, 3043 * the transition from allocated to free for managed 3044 * pages is blocked by the page busy lock.) (3) It is 3045 * allocated but not contained by an object and not 3046 * wired, e.g., allocated by Xen's balloon driver. 3047 */ 3048 run_ext = 0; 3049 } 3050 3051 /* 3052 * Extend or reset the current run of pages. 3053 */ 3054 if (run_ext > 0) { 3055 if (run_len == 0) 3056 m_run = m; 3057 run_len += run_ext; 3058 } else { 3059 if (run_len > 0) { 3060 m_run = NULL; 3061 run_len = 0; 3062 } 3063 } 3064 } 3065 if (run_len >= npages) 3066 return (m_run); 3067 return (NULL); 3068 } 3069 3070 /* 3071 * vm_page_reclaim_run: 3072 * 3073 * Try to relocate each of the allocated virtual pages within the 3074 * specified run of physical pages to a new physical address. Free the 3075 * physical pages underlying the relocated virtual pages. A virtual page 3076 * is relocatable if and only if it could be laundered or reclaimed by 3077 * the page daemon. Whenever possible, a virtual page is relocated to a 3078 * physical address above "high". 3079 * 3080 * Returns 0 if every physical page within the run was already free or 3081 * just freed by a successful relocation. Otherwise, returns a non-zero 3082 * value indicating why the last attempt to relocate a virtual page was 3083 * unsuccessful. 3084 * 3085 * "req_class" must be an allocation class. 3086 */ 3087 static int 3088 vm_page_reclaim_run(int req_class, int domain, u_long npages, vm_page_t m_run, 3089 vm_paddr_t high) 3090 { 3091 struct vm_domain *vmd; 3092 struct spglist free; 3093 vm_object_t object; 3094 vm_paddr_t pa; 3095 vm_page_t m, m_end, m_new; 3096 int error, order, req; 3097 3098 KASSERT((req_class & VM_ALLOC_CLASS_MASK) == req_class, 3099 ("req_class is not an allocation class")); 3100 SLIST_INIT(&free); 3101 error = 0; 3102 m = m_run; 3103 m_end = m_run + npages; 3104 for (; error == 0 && m < m_end; m++) { 3105 KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0, 3106 ("page %p is PG_FICTITIOUS or PG_MARKER", m)); 3107 3108 /* 3109 * Racily check for wirings. Races are handled once the object 3110 * lock is held and the page is unmapped. 3111 */ 3112 if (vm_page_wired(m)) 3113 error = EBUSY; 3114 else if ((object = atomic_load_ptr(&m->object)) != NULL) { 3115 /* 3116 * The page is relocated if and only if it could be 3117 * laundered or reclaimed by the page daemon. 3118 */ 3119 VM_OBJECT_WLOCK(object); 3120 /* Don't care: PG_NODUMP, PG_ZERO. */ 3121 if (m->object != object || 3122 ((object->flags & OBJ_SWAP) == 0 && 3123 object->type != OBJT_VNODE)) 3124 error = EINVAL; 3125 else if (object->memattr != VM_MEMATTR_DEFAULT) 3126 error = EINVAL; 3127 else if (vm_page_queue(m) != PQ_NONE && 3128 vm_page_tryxbusy(m) != 0) { 3129 if (vm_page_wired(m)) { 3130 vm_page_xunbusy(m); 3131 error = EBUSY; 3132 goto unlock; 3133 } 3134 KASSERT(pmap_page_get_memattr(m) == 3135 VM_MEMATTR_DEFAULT, 3136 ("page %p has an unexpected memattr", m)); 3137 KASSERT(m->oflags == 0, 3138 ("page %p has unexpected oflags", m)); 3139 /* Don't care: PGA_NOSYNC. */ 3140 if (!vm_page_none_valid(m)) { 3141 /* 3142 * First, try to allocate a new page 3143 * that is above "high". Failing 3144 * that, try to allocate a new page 3145 * that is below "m_run". Allocate 3146 * the new page between the end of 3147 * "m_run" and "high" only as a last 3148 * resort. 3149 */ 3150 req = req_class; 3151 if ((m->flags & PG_NODUMP) != 0) 3152 req |= VM_ALLOC_NODUMP; 3153 if (trunc_page(high) != 3154 ~(vm_paddr_t)PAGE_MASK) { 3155 m_new = 3156 vm_page_alloc_noobj_contig( 3157 req, 1, round_page(high), 3158 ~(vm_paddr_t)0, PAGE_SIZE, 3159 0, VM_MEMATTR_DEFAULT); 3160 } else 3161 m_new = NULL; 3162 if (m_new == NULL) { 3163 pa = VM_PAGE_TO_PHYS(m_run); 3164 m_new = 3165 vm_page_alloc_noobj_contig( 3166 req, 1, 0, pa - 1, 3167 PAGE_SIZE, 0, 3168 VM_MEMATTR_DEFAULT); 3169 } 3170 if (m_new == NULL) { 3171 pa += ptoa(npages); 3172 m_new = 3173 vm_page_alloc_noobj_contig( 3174 req, 1, pa, high, PAGE_SIZE, 3175 0, VM_MEMATTR_DEFAULT); 3176 } 3177 if (m_new == NULL) { 3178 vm_page_xunbusy(m); 3179 error = ENOMEM; 3180 goto unlock; 3181 } 3182 3183 /* 3184 * Unmap the page and check for new 3185 * wirings that may have been acquired 3186 * through a pmap lookup. 3187 */ 3188 if (object->ref_count != 0 && 3189 !vm_page_try_remove_all(m)) { 3190 vm_page_xunbusy(m); 3191 vm_page_free(m_new); 3192 error = EBUSY; 3193 goto unlock; 3194 } 3195 3196 /* 3197 * Replace "m" with the new page. For 3198 * vm_page_replace(), "m" must be busy 3199 * and dequeued. Finally, change "m" 3200 * as if vm_page_free() was called. 3201 */ 3202 m_new->a.flags = m->a.flags & 3203 ~PGA_QUEUE_STATE_MASK; 3204 KASSERT(m_new->oflags == VPO_UNMANAGED, 3205 ("page %p is managed", m_new)); 3206 m_new->oflags = 0; 3207 pmap_copy_page(m, m_new); 3208 m_new->valid = m->valid; 3209 m_new->dirty = m->dirty; 3210 m->flags &= ~PG_ZERO; 3211 vm_page_dequeue(m); 3212 if (vm_page_replace_hold(m_new, object, 3213 m->pindex, m) && 3214 vm_page_free_prep(m)) 3215 SLIST_INSERT_HEAD(&free, m, 3216 plinks.s.ss); 3217 3218 /* 3219 * The new page must be deactivated 3220 * before the object is unlocked. 3221 */ 3222 vm_page_deactivate(m_new); 3223 } else { 3224 m->flags &= ~PG_ZERO; 3225 vm_page_dequeue(m); 3226 if (vm_page_free_prep(m)) 3227 SLIST_INSERT_HEAD(&free, m, 3228 plinks.s.ss); 3229 KASSERT(m->dirty == 0, 3230 ("page %p is dirty", m)); 3231 } 3232 } else 3233 error = EBUSY; 3234 unlock: 3235 VM_OBJECT_WUNLOCK(object); 3236 } else { 3237 MPASS(vm_page_domain(m) == domain); 3238 vmd = VM_DOMAIN(domain); 3239 vm_domain_free_lock(vmd); 3240 order = m->order; 3241 if (order < VM_NFREEORDER) { 3242 /* 3243 * The page is enqueued in the physical memory 3244 * allocator's free page queues. Moreover, it 3245 * is the first page in a power-of-two-sized 3246 * run of contiguous free pages. Jump ahead 3247 * to the last page within that run, and 3248 * continue from there. 3249 */ 3250 m += (1 << order) - 1; 3251 } 3252 #if VM_NRESERVLEVEL > 0 3253 else if (vm_reserv_is_page_free(m)) 3254 order = 0; 3255 #endif 3256 vm_domain_free_unlock(vmd); 3257 if (order == VM_NFREEORDER) 3258 error = EINVAL; 3259 } 3260 } 3261 if ((m = SLIST_FIRST(&free)) != NULL) { 3262 int cnt; 3263 3264 vmd = VM_DOMAIN(domain); 3265 cnt = 0; 3266 vm_domain_free_lock(vmd); 3267 do { 3268 MPASS(vm_page_domain(m) == domain); 3269 SLIST_REMOVE_HEAD(&free, plinks.s.ss); 3270 vm_phys_free_pages(m, 0); 3271 cnt++; 3272 } while ((m = SLIST_FIRST(&free)) != NULL); 3273 vm_domain_free_unlock(vmd); 3274 vm_domain_freecnt_inc(vmd, cnt); 3275 } 3276 return (error); 3277 } 3278 3279 #define NRUNS 16 3280 3281 #define RUN_INDEX(count, nruns) ((count) % (nruns)) 3282 3283 #define MIN_RECLAIM 8 3284 3285 /* 3286 * vm_page_reclaim_contig: 3287 * 3288 * Reclaim allocated, contiguous physical memory satisfying the specified 3289 * conditions by relocating the virtual pages using that physical memory. 3290 * Returns 0 if reclamation is successful, ERANGE if the specified domain 3291 * can't possibly satisfy the reclamation request, or ENOMEM if not 3292 * currently able to reclaim the requested number of pages. Since 3293 * relocation requires the allocation of physical pages, reclamation may 3294 * fail with ENOMEM due to a shortage of free pages. When reclamation 3295 * fails in this manner, callers are expected to perform vm_wait() before 3296 * retrying a failed allocation operation, e.g., vm_page_alloc_contig(). 3297 * 3298 * The caller must always specify an allocation class through "req". 3299 * 3300 * allocation classes: 3301 * VM_ALLOC_NORMAL normal process request 3302 * VM_ALLOC_SYSTEM system *really* needs a page 3303 * VM_ALLOC_INTERRUPT interrupt time request 3304 * 3305 * The optional allocation flags are ignored. 3306 * 3307 * "npages" must be greater than zero. Both "alignment" and "boundary" 3308 * must be a power of two. 3309 */ 3310 int 3311 vm_page_reclaim_contig_domain_ext(int domain, int req, u_long npages, 3312 vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary, 3313 int desired_runs) 3314 { 3315 struct vm_domain *vmd; 3316 vm_page_t bounds[2], m_run, _m_runs[NRUNS], *m_runs; 3317 u_long count, minalign, reclaimed; 3318 int error, i, min_reclaim, nruns, options, req_class; 3319 int segind, start_segind; 3320 int ret; 3321 3322 KASSERT(npages > 0, ("npages is 0")); 3323 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 3324 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 3325 3326 ret = ENOMEM; 3327 3328 /* 3329 * If the caller wants to reclaim multiple runs, try to allocate 3330 * space to store the runs. If that fails, fall back to the old 3331 * behavior of just reclaiming MIN_RECLAIM pages. 3332 */ 3333 if (desired_runs > 1) 3334 m_runs = malloc((NRUNS + desired_runs) * sizeof(*m_runs), 3335 M_TEMP, M_NOWAIT); 3336 else 3337 m_runs = NULL; 3338 3339 if (m_runs == NULL) { 3340 m_runs = _m_runs; 3341 nruns = NRUNS; 3342 } else { 3343 nruns = NRUNS + desired_runs - 1; 3344 } 3345 min_reclaim = MAX(desired_runs * npages, MIN_RECLAIM); 3346 3347 /* 3348 * The caller will attempt an allocation after some runs have been 3349 * reclaimed and added to the vm_phys buddy lists. Due to limitations 3350 * of vm_phys_alloc_contig(), round up the requested length to the next 3351 * power of two or maximum chunk size, and ensure that each run is 3352 * suitably aligned. 3353 */ 3354 minalign = 1ul << imin(flsl(npages - 1), VM_NFREEORDER - 1); 3355 npages = roundup2(npages, minalign); 3356 if (alignment < ptoa(minalign)) 3357 alignment = ptoa(minalign); 3358 3359 /* 3360 * The page daemon is allowed to dig deeper into the free page list. 3361 */ 3362 req_class = req & VM_ALLOC_CLASS_MASK; 3363 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 3364 req_class = VM_ALLOC_SYSTEM; 3365 3366 start_segind = vm_phys_lookup_segind(low); 3367 3368 /* 3369 * Return if the number of free pages cannot satisfy the requested 3370 * allocation. 3371 */ 3372 vmd = VM_DOMAIN(domain); 3373 count = vmd->vmd_free_count; 3374 if (count < npages + vmd->vmd_free_reserved || (count < npages + 3375 vmd->vmd_interrupt_free_min && req_class == VM_ALLOC_SYSTEM) || 3376 (count < npages && req_class == VM_ALLOC_INTERRUPT)) 3377 goto done; 3378 3379 /* 3380 * Scan up to three times, relaxing the restrictions ("options") on 3381 * the reclamation of reservations and superpages each time. 3382 */ 3383 for (options = VPSC_NORESERV;;) { 3384 bool phys_range_exists = false; 3385 3386 /* 3387 * Find the highest runs that satisfy the given constraints 3388 * and restrictions, and record them in "m_runs". 3389 */ 3390 count = 0; 3391 segind = start_segind; 3392 while ((segind = vm_phys_find_range(bounds, segind, domain, 3393 npages, low, high)) != -1) { 3394 phys_range_exists = true; 3395 while ((m_run = vm_page_scan_contig(npages, bounds[0], 3396 bounds[1], alignment, boundary, options))) { 3397 bounds[0] = m_run + npages; 3398 m_runs[RUN_INDEX(count, nruns)] = m_run; 3399 count++; 3400 } 3401 segind++; 3402 } 3403 3404 if (!phys_range_exists) { 3405 ret = ERANGE; 3406 goto done; 3407 } 3408 3409 /* 3410 * Reclaim the highest runs in LIFO (descending) order until 3411 * the number of reclaimed pages, "reclaimed", is at least 3412 * "min_reclaim". Reset "reclaimed" each time because each 3413 * reclamation is idempotent, and runs will (likely) recur 3414 * from one scan to the next as restrictions are relaxed. 3415 */ 3416 reclaimed = 0; 3417 for (i = 0; count > 0 && i < nruns; i++) { 3418 count--; 3419 m_run = m_runs[RUN_INDEX(count, nruns)]; 3420 error = vm_page_reclaim_run(req_class, domain, npages, 3421 m_run, high); 3422 if (error == 0) { 3423 reclaimed += npages; 3424 if (reclaimed >= min_reclaim) { 3425 ret = 0; 3426 goto done; 3427 } 3428 } 3429 } 3430 3431 /* 3432 * Either relax the restrictions on the next scan or return if 3433 * the last scan had no restrictions. 3434 */ 3435 if (options == VPSC_NORESERV) 3436 options = VPSC_NOSUPER; 3437 else if (options == VPSC_NOSUPER) 3438 options = VPSC_ANY; 3439 else if (options == VPSC_ANY) { 3440 if (reclaimed != 0) 3441 ret = 0; 3442 goto done; 3443 } 3444 } 3445 done: 3446 if (m_runs != _m_runs) 3447 free(m_runs, M_TEMP); 3448 return (ret); 3449 } 3450 3451 int 3452 vm_page_reclaim_contig_domain(int domain, int req, u_long npages, 3453 vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary) 3454 { 3455 return (vm_page_reclaim_contig_domain_ext(domain, req, npages, low, high, 3456 alignment, boundary, 1)); 3457 } 3458 3459 int 3460 vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low, vm_paddr_t high, 3461 u_long alignment, vm_paddr_t boundary) 3462 { 3463 struct vm_domainset_iter di; 3464 int domain, ret, status; 3465 3466 ret = ERANGE; 3467 3468 vm_domainset_iter_page_init(&di, NULL, 0, &domain, &req); 3469 do { 3470 status = vm_page_reclaim_contig_domain(domain, req, npages, low, 3471 high, alignment, boundary); 3472 if (status == 0) 3473 return (0); 3474 else if (status == ERANGE) 3475 vm_domainset_iter_ignore(&di, domain); 3476 else { 3477 KASSERT(status == ENOMEM, ("Unrecognized error %d " 3478 "from vm_page_reclaim_contig_domain()", status)); 3479 ret = ENOMEM; 3480 } 3481 } while (vm_domainset_iter_page(&di, NULL, &domain) == 0); 3482 3483 return (ret); 3484 } 3485 3486 /* 3487 * Set the domain in the appropriate page level domainset. 3488 */ 3489 void 3490 vm_domain_set(struct vm_domain *vmd) 3491 { 3492 3493 mtx_lock(&vm_domainset_lock); 3494 if (!vmd->vmd_minset && vm_paging_min(vmd)) { 3495 vmd->vmd_minset = 1; 3496 DOMAINSET_SET(vmd->vmd_domain, &vm_min_domains); 3497 } 3498 if (!vmd->vmd_severeset && vm_paging_severe(vmd)) { 3499 vmd->vmd_severeset = 1; 3500 DOMAINSET_SET(vmd->vmd_domain, &vm_severe_domains); 3501 } 3502 mtx_unlock(&vm_domainset_lock); 3503 } 3504 3505 /* 3506 * Clear the domain from the appropriate page level domainset. 3507 */ 3508 void 3509 vm_domain_clear(struct vm_domain *vmd) 3510 { 3511 3512 mtx_lock(&vm_domainset_lock); 3513 if (vmd->vmd_minset && !vm_paging_min(vmd)) { 3514 vmd->vmd_minset = 0; 3515 DOMAINSET_CLR(vmd->vmd_domain, &vm_min_domains); 3516 if (vm_min_waiters != 0) { 3517 vm_min_waiters = 0; 3518 wakeup(&vm_min_domains); 3519 } 3520 } 3521 if (vmd->vmd_severeset && !vm_paging_severe(vmd)) { 3522 vmd->vmd_severeset = 0; 3523 DOMAINSET_CLR(vmd->vmd_domain, &vm_severe_domains); 3524 if (vm_severe_waiters != 0) { 3525 vm_severe_waiters = 0; 3526 wakeup(&vm_severe_domains); 3527 } 3528 } 3529 3530 /* 3531 * If pageout daemon needs pages, then tell it that there are 3532 * some free. 3533 */ 3534 if (vmd->vmd_pageout_pages_needed && 3535 vmd->vmd_free_count >= vmd->vmd_pageout_free_min) { 3536 wakeup(&vmd->vmd_pageout_pages_needed); 3537 vmd->vmd_pageout_pages_needed = 0; 3538 } 3539 3540 /* See comments in vm_wait_doms(). */ 3541 if (vm_pageproc_waiters) { 3542 vm_pageproc_waiters = 0; 3543 wakeup(&vm_pageproc_waiters); 3544 } 3545 mtx_unlock(&vm_domainset_lock); 3546 } 3547 3548 /* 3549 * Wait for free pages to exceed the min threshold globally. 3550 */ 3551 void 3552 vm_wait_min(void) 3553 { 3554 3555 mtx_lock(&vm_domainset_lock); 3556 while (vm_page_count_min()) { 3557 vm_min_waiters++; 3558 msleep(&vm_min_domains, &vm_domainset_lock, PVM, "vmwait", 0); 3559 } 3560 mtx_unlock(&vm_domainset_lock); 3561 } 3562 3563 /* 3564 * Wait for free pages to exceed the severe threshold globally. 3565 */ 3566 void 3567 vm_wait_severe(void) 3568 { 3569 3570 mtx_lock(&vm_domainset_lock); 3571 while (vm_page_count_severe()) { 3572 vm_severe_waiters++; 3573 msleep(&vm_severe_domains, &vm_domainset_lock, PVM, 3574 "vmwait", 0); 3575 } 3576 mtx_unlock(&vm_domainset_lock); 3577 } 3578 3579 u_int 3580 vm_wait_count(void) 3581 { 3582 3583 return (vm_severe_waiters + vm_min_waiters + vm_pageproc_waiters); 3584 } 3585 3586 int 3587 vm_wait_doms(const domainset_t *wdoms, int mflags) 3588 { 3589 int error; 3590 3591 error = 0; 3592 3593 /* 3594 * We use racey wakeup synchronization to avoid expensive global 3595 * locking for the pageproc when sleeping with a non-specific vm_wait. 3596 * To handle this, we only sleep for one tick in this instance. It 3597 * is expected that most allocations for the pageproc will come from 3598 * kmem or vm_page_grab* which will use the more specific and 3599 * race-free vm_wait_domain(). 3600 */ 3601 if (curproc == pageproc) { 3602 mtx_lock(&vm_domainset_lock); 3603 vm_pageproc_waiters++; 3604 error = msleep(&vm_pageproc_waiters, &vm_domainset_lock, 3605 PVM | PDROP | mflags, "pageprocwait", 1); 3606 } else { 3607 /* 3608 * XXX Ideally we would wait only until the allocation could 3609 * be satisfied. This condition can cause new allocators to 3610 * consume all freed pages while old allocators wait. 3611 */ 3612 mtx_lock(&vm_domainset_lock); 3613 if (vm_page_count_min_set(wdoms)) { 3614 if (pageproc == NULL) 3615 panic("vm_wait in early boot"); 3616 vm_min_waiters++; 3617 error = msleep(&vm_min_domains, &vm_domainset_lock, 3618 PVM | PDROP | mflags, "vmwait", 0); 3619 } else 3620 mtx_unlock(&vm_domainset_lock); 3621 } 3622 return (error); 3623 } 3624 3625 /* 3626 * vm_wait_domain: 3627 * 3628 * Sleep until free pages are available for allocation. 3629 * - Called in various places after failed memory allocations. 3630 */ 3631 void 3632 vm_wait_domain(int domain) 3633 { 3634 struct vm_domain *vmd; 3635 domainset_t wdom; 3636 3637 vmd = VM_DOMAIN(domain); 3638 vm_domain_free_assert_unlocked(vmd); 3639 3640 if (curproc == pageproc) { 3641 mtx_lock(&vm_domainset_lock); 3642 if (vmd->vmd_free_count < vmd->vmd_pageout_free_min) { 3643 vmd->vmd_pageout_pages_needed = 1; 3644 msleep(&vmd->vmd_pageout_pages_needed, 3645 &vm_domainset_lock, PDROP | PSWP, "VMWait", 0); 3646 } else 3647 mtx_unlock(&vm_domainset_lock); 3648 } else { 3649 DOMAINSET_ZERO(&wdom); 3650 DOMAINSET_SET(vmd->vmd_domain, &wdom); 3651 vm_wait_doms(&wdom, 0); 3652 } 3653 } 3654 3655 static int 3656 vm_wait_flags(vm_object_t obj, int mflags) 3657 { 3658 struct domainset *d; 3659 3660 d = NULL; 3661 3662 /* 3663 * Carefully fetch pointers only once: the struct domainset 3664 * itself is ummutable but the pointer might change. 3665 */ 3666 if (obj != NULL) 3667 d = obj->domain.dr_policy; 3668 if (d == NULL) 3669 d = curthread->td_domain.dr_policy; 3670 3671 return (vm_wait_doms(&d->ds_mask, mflags)); 3672 } 3673 3674 /* 3675 * vm_wait: 3676 * 3677 * Sleep until free pages are available for allocation in the 3678 * affinity domains of the obj. If obj is NULL, the domain set 3679 * for the calling thread is used. 3680 * Called in various places after failed memory allocations. 3681 */ 3682 void 3683 vm_wait(vm_object_t obj) 3684 { 3685 (void)vm_wait_flags(obj, 0); 3686 } 3687 3688 int 3689 vm_wait_intr(vm_object_t obj) 3690 { 3691 return (vm_wait_flags(obj, PCATCH)); 3692 } 3693 3694 /* 3695 * vm_domain_alloc_fail: 3696 * 3697 * Called when a page allocation function fails. Informs the 3698 * pagedaemon and performs the requested wait. Requires the 3699 * domain_free and object lock on entry. Returns with the 3700 * object lock held and free lock released. Returns an error when 3701 * retry is necessary. 3702 * 3703 */ 3704 static int 3705 vm_domain_alloc_fail(struct vm_domain *vmd, vm_object_t object, int req) 3706 { 3707 3708 vm_domain_free_assert_unlocked(vmd); 3709 3710 atomic_add_int(&vmd->vmd_pageout_deficit, 3711 max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1)); 3712 if (req & (VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL)) { 3713 if (object != NULL) 3714 VM_OBJECT_WUNLOCK(object); 3715 vm_wait_domain(vmd->vmd_domain); 3716 if (object != NULL) 3717 VM_OBJECT_WLOCK(object); 3718 if (req & VM_ALLOC_WAITOK) 3719 return (EAGAIN); 3720 } 3721 3722 return (0); 3723 } 3724 3725 /* 3726 * vm_waitpfault: 3727 * 3728 * Sleep until free pages are available for allocation. 3729 * - Called only in vm_fault so that processes page faulting 3730 * can be easily tracked. 3731 * - Sleeps at a lower priority than vm_wait() so that vm_wait()ing 3732 * processes will be able to grab memory first. Do not change 3733 * this balance without careful testing first. 3734 */ 3735 void 3736 vm_waitpfault(struct domainset *dset, int timo) 3737 { 3738 3739 /* 3740 * XXX Ideally we would wait only until the allocation could 3741 * be satisfied. This condition can cause new allocators to 3742 * consume all freed pages while old allocators wait. 3743 */ 3744 mtx_lock(&vm_domainset_lock); 3745 if (vm_page_count_min_set(&dset->ds_mask)) { 3746 vm_min_waiters++; 3747 msleep(&vm_min_domains, &vm_domainset_lock, PUSER | PDROP, 3748 "pfault", timo); 3749 } else 3750 mtx_unlock(&vm_domainset_lock); 3751 } 3752 3753 static struct vm_pagequeue * 3754 _vm_page_pagequeue(vm_page_t m, uint8_t queue) 3755 { 3756 3757 return (&vm_pagequeue_domain(m)->vmd_pagequeues[queue]); 3758 } 3759 3760 #ifdef INVARIANTS 3761 static struct vm_pagequeue * 3762 vm_page_pagequeue(vm_page_t m) 3763 { 3764 3765 return (_vm_page_pagequeue(m, vm_page_astate_load(m).queue)); 3766 } 3767 #endif 3768 3769 static __always_inline bool 3770 vm_page_pqstate_fcmpset(vm_page_t m, vm_page_astate_t *old, vm_page_astate_t new) 3771 { 3772 vm_page_astate_t tmp; 3773 3774 tmp = *old; 3775 do { 3776 if (__predict_true(vm_page_astate_fcmpset(m, old, new))) 3777 return (true); 3778 counter_u64_add(pqstate_commit_retries, 1); 3779 } while (old->_bits == tmp._bits); 3780 3781 return (false); 3782 } 3783 3784 /* 3785 * Do the work of committing a queue state update that moves the page out of 3786 * its current queue. 3787 */ 3788 static bool 3789 _vm_page_pqstate_commit_dequeue(struct vm_pagequeue *pq, vm_page_t m, 3790 vm_page_astate_t *old, vm_page_astate_t new) 3791 { 3792 vm_page_t next; 3793 3794 vm_pagequeue_assert_locked(pq); 3795 KASSERT(vm_page_pagequeue(m) == pq, 3796 ("%s: queue %p does not match page %p", __func__, pq, m)); 3797 KASSERT(old->queue != PQ_NONE && new.queue != old->queue, 3798 ("%s: invalid queue indices %d %d", 3799 __func__, old->queue, new.queue)); 3800 3801 /* 3802 * Once the queue index of the page changes there is nothing 3803 * synchronizing with further updates to the page's physical 3804 * queue state. Therefore we must speculatively remove the page 3805 * from the queue now and be prepared to roll back if the queue 3806 * state update fails. If the page is not physically enqueued then 3807 * we just update its queue index. 3808 */ 3809 if ((old->flags & PGA_ENQUEUED) != 0) { 3810 new.flags &= ~PGA_ENQUEUED; 3811 next = TAILQ_NEXT(m, plinks.q); 3812 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 3813 vm_pagequeue_cnt_dec(pq); 3814 if (!vm_page_pqstate_fcmpset(m, old, new)) { 3815 if (next == NULL) 3816 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 3817 else 3818 TAILQ_INSERT_BEFORE(next, m, plinks.q); 3819 vm_pagequeue_cnt_inc(pq); 3820 return (false); 3821 } else { 3822 return (true); 3823 } 3824 } else { 3825 return (vm_page_pqstate_fcmpset(m, old, new)); 3826 } 3827 } 3828 3829 static bool 3830 vm_page_pqstate_commit_dequeue(vm_page_t m, vm_page_astate_t *old, 3831 vm_page_astate_t new) 3832 { 3833 struct vm_pagequeue *pq; 3834 vm_page_astate_t as; 3835 bool ret; 3836 3837 pq = _vm_page_pagequeue(m, old->queue); 3838 3839 /* 3840 * The queue field and PGA_ENQUEUED flag are stable only so long as the 3841 * corresponding page queue lock is held. 3842 */ 3843 vm_pagequeue_lock(pq); 3844 as = vm_page_astate_load(m); 3845 if (__predict_false(as._bits != old->_bits)) { 3846 *old = as; 3847 ret = false; 3848 } else { 3849 ret = _vm_page_pqstate_commit_dequeue(pq, m, old, new); 3850 } 3851 vm_pagequeue_unlock(pq); 3852 return (ret); 3853 } 3854 3855 /* 3856 * Commit a queue state update that enqueues or requeues a page. 3857 */ 3858 static bool 3859 _vm_page_pqstate_commit_requeue(struct vm_pagequeue *pq, vm_page_t m, 3860 vm_page_astate_t *old, vm_page_astate_t new) 3861 { 3862 struct vm_domain *vmd; 3863 3864 vm_pagequeue_assert_locked(pq); 3865 KASSERT(old->queue != PQ_NONE && new.queue == old->queue, 3866 ("%s: invalid queue indices %d %d", 3867 __func__, old->queue, new.queue)); 3868 3869 new.flags |= PGA_ENQUEUED; 3870 if (!vm_page_pqstate_fcmpset(m, old, new)) 3871 return (false); 3872 3873 if ((old->flags & PGA_ENQUEUED) != 0) 3874 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 3875 else 3876 vm_pagequeue_cnt_inc(pq); 3877 3878 /* 3879 * Give PGA_REQUEUE_HEAD precedence over PGA_REQUEUE. In particular, if 3880 * both flags are set in close succession, only PGA_REQUEUE_HEAD will be 3881 * applied, even if it was set first. 3882 */ 3883 if ((old->flags & PGA_REQUEUE_HEAD) != 0) { 3884 vmd = vm_pagequeue_domain(m); 3885 KASSERT(pq == &vmd->vmd_pagequeues[PQ_INACTIVE], 3886 ("%s: invalid page queue for page %p", __func__, m)); 3887 TAILQ_INSERT_BEFORE(&vmd->vmd_inacthead, m, plinks.q); 3888 } else { 3889 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 3890 } 3891 return (true); 3892 } 3893 3894 /* 3895 * Commit a queue state update that encodes a request for a deferred queue 3896 * operation. 3897 */ 3898 static bool 3899 vm_page_pqstate_commit_request(vm_page_t m, vm_page_astate_t *old, 3900 vm_page_astate_t new) 3901 { 3902 3903 KASSERT(old->queue == new.queue || new.queue != PQ_NONE, 3904 ("%s: invalid state, queue %d flags %x", 3905 __func__, new.queue, new.flags)); 3906 3907 if (old->_bits != new._bits && 3908 !vm_page_pqstate_fcmpset(m, old, new)) 3909 return (false); 3910 vm_page_pqbatch_submit(m, new.queue); 3911 return (true); 3912 } 3913 3914 /* 3915 * A generic queue state update function. This handles more cases than the 3916 * specialized functions above. 3917 */ 3918 bool 3919 vm_page_pqstate_commit(vm_page_t m, vm_page_astate_t *old, vm_page_astate_t new) 3920 { 3921 3922 if (old->_bits == new._bits) 3923 return (true); 3924 3925 if (old->queue != PQ_NONE && new.queue != old->queue) { 3926 if (!vm_page_pqstate_commit_dequeue(m, old, new)) 3927 return (false); 3928 if (new.queue != PQ_NONE) 3929 vm_page_pqbatch_submit(m, new.queue); 3930 } else { 3931 if (!vm_page_pqstate_fcmpset(m, old, new)) 3932 return (false); 3933 if (new.queue != PQ_NONE && 3934 ((new.flags & ~old->flags) & PGA_QUEUE_OP_MASK) != 0) 3935 vm_page_pqbatch_submit(m, new.queue); 3936 } 3937 return (true); 3938 } 3939 3940 /* 3941 * Apply deferred queue state updates to a page. 3942 */ 3943 static inline void 3944 vm_pqbatch_process_page(struct vm_pagequeue *pq, vm_page_t m, uint8_t queue) 3945 { 3946 vm_page_astate_t new, old; 3947 3948 CRITICAL_ASSERT(curthread); 3949 vm_pagequeue_assert_locked(pq); 3950 KASSERT(queue < PQ_COUNT, 3951 ("%s: invalid queue index %d", __func__, queue)); 3952 KASSERT(pq == _vm_page_pagequeue(m, queue), 3953 ("%s: page %p does not belong to queue %p", __func__, m, pq)); 3954 3955 for (old = vm_page_astate_load(m);;) { 3956 if (__predict_false(old.queue != queue || 3957 (old.flags & PGA_QUEUE_OP_MASK) == 0)) { 3958 counter_u64_add(queue_nops, 1); 3959 break; 3960 } 3961 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 3962 ("%s: page %p is unmanaged", __func__, m)); 3963 3964 new = old; 3965 if ((old.flags & PGA_DEQUEUE) != 0) { 3966 new.flags &= ~PGA_QUEUE_OP_MASK; 3967 new.queue = PQ_NONE; 3968 if (__predict_true(_vm_page_pqstate_commit_dequeue(pq, 3969 m, &old, new))) { 3970 counter_u64_add(queue_ops, 1); 3971 break; 3972 } 3973 } else { 3974 new.flags &= ~(PGA_REQUEUE | PGA_REQUEUE_HEAD); 3975 if (__predict_true(_vm_page_pqstate_commit_requeue(pq, 3976 m, &old, new))) { 3977 counter_u64_add(queue_ops, 1); 3978 break; 3979 } 3980 } 3981 } 3982 } 3983 3984 static void 3985 vm_pqbatch_process(struct vm_pagequeue *pq, struct vm_batchqueue *bq, 3986 uint8_t queue) 3987 { 3988 int i; 3989 3990 for (i = 0; i < bq->bq_cnt; i++) 3991 vm_pqbatch_process_page(pq, bq->bq_pa[i], queue); 3992 vm_batchqueue_init(bq); 3993 } 3994 3995 /* 3996 * vm_page_pqbatch_submit: [ internal use only ] 3997 * 3998 * Enqueue a page in the specified page queue's batched work queue. 3999 * The caller must have encoded the requested operation in the page 4000 * structure's a.flags field. 4001 */ 4002 void 4003 vm_page_pqbatch_submit(vm_page_t m, uint8_t queue) 4004 { 4005 struct vm_batchqueue *bq; 4006 struct vm_pagequeue *pq; 4007 int domain, slots_remaining; 4008 4009 KASSERT(queue < PQ_COUNT, ("invalid queue %d", queue)); 4010 4011 domain = vm_page_domain(m); 4012 critical_enter(); 4013 bq = DPCPU_PTR(pqbatch[domain][queue]); 4014 slots_remaining = vm_batchqueue_insert(bq, m); 4015 if (slots_remaining > (VM_BATCHQUEUE_SIZE >> 1)) { 4016 /* keep building the bq */ 4017 critical_exit(); 4018 return; 4019 } else if (slots_remaining > 0 ) { 4020 /* Try to process the bq if we can get the lock */ 4021 pq = &VM_DOMAIN(domain)->vmd_pagequeues[queue]; 4022 if (vm_pagequeue_trylock(pq)) { 4023 vm_pqbatch_process(pq, bq, queue); 4024 vm_pagequeue_unlock(pq); 4025 } 4026 critical_exit(); 4027 return; 4028 } 4029 critical_exit(); 4030 4031 /* if we make it here, the bq is full so wait for the lock */ 4032 4033 pq = &VM_DOMAIN(domain)->vmd_pagequeues[queue]; 4034 vm_pagequeue_lock(pq); 4035 critical_enter(); 4036 bq = DPCPU_PTR(pqbatch[domain][queue]); 4037 vm_pqbatch_process(pq, bq, queue); 4038 vm_pqbatch_process_page(pq, m, queue); 4039 vm_pagequeue_unlock(pq); 4040 critical_exit(); 4041 } 4042 4043 /* 4044 * vm_page_pqbatch_drain: [ internal use only ] 4045 * 4046 * Force all per-CPU page queue batch queues to be drained. This is 4047 * intended for use in severe memory shortages, to ensure that pages 4048 * do not remain stuck in the batch queues. 4049 */ 4050 void 4051 vm_page_pqbatch_drain(void) 4052 { 4053 struct thread *td; 4054 struct vm_domain *vmd; 4055 struct vm_pagequeue *pq; 4056 int cpu, domain, queue; 4057 4058 td = curthread; 4059 CPU_FOREACH(cpu) { 4060 thread_lock(td); 4061 sched_bind(td, cpu); 4062 thread_unlock(td); 4063 4064 for (domain = 0; domain < vm_ndomains; domain++) { 4065 vmd = VM_DOMAIN(domain); 4066 for (queue = 0; queue < PQ_COUNT; queue++) { 4067 pq = &vmd->vmd_pagequeues[queue]; 4068 vm_pagequeue_lock(pq); 4069 critical_enter(); 4070 vm_pqbatch_process(pq, 4071 DPCPU_PTR(pqbatch[domain][queue]), queue); 4072 critical_exit(); 4073 vm_pagequeue_unlock(pq); 4074 } 4075 } 4076 } 4077 thread_lock(td); 4078 sched_unbind(td); 4079 thread_unlock(td); 4080 } 4081 4082 /* 4083 * vm_page_dequeue_deferred: [ internal use only ] 4084 * 4085 * Request removal of the given page from its current page 4086 * queue. Physical removal from the queue may be deferred 4087 * indefinitely. 4088 */ 4089 void 4090 vm_page_dequeue_deferred(vm_page_t m) 4091 { 4092 vm_page_astate_t new, old; 4093 4094 old = vm_page_astate_load(m); 4095 do { 4096 if (old.queue == PQ_NONE) { 4097 KASSERT((old.flags & PGA_QUEUE_STATE_MASK) == 0, 4098 ("%s: page %p has unexpected queue state", 4099 __func__, m)); 4100 break; 4101 } 4102 new = old; 4103 new.flags |= PGA_DEQUEUE; 4104 } while (!vm_page_pqstate_commit_request(m, &old, new)); 4105 } 4106 4107 /* 4108 * vm_page_dequeue: 4109 * 4110 * Remove the page from whichever page queue it's in, if any, before 4111 * returning. 4112 */ 4113 void 4114 vm_page_dequeue(vm_page_t m) 4115 { 4116 vm_page_astate_t new, old; 4117 4118 old = vm_page_astate_load(m); 4119 do { 4120 if (old.queue == PQ_NONE) { 4121 KASSERT((old.flags & PGA_QUEUE_STATE_MASK) == 0, 4122 ("%s: page %p has unexpected queue state", 4123 __func__, m)); 4124 break; 4125 } 4126 new = old; 4127 new.flags &= ~PGA_QUEUE_OP_MASK; 4128 new.queue = PQ_NONE; 4129 } while (!vm_page_pqstate_commit_dequeue(m, &old, new)); 4130 4131 } 4132 4133 /* 4134 * Schedule the given page for insertion into the specified page queue. 4135 * Physical insertion of the page may be deferred indefinitely. 4136 */ 4137 static void 4138 vm_page_enqueue(vm_page_t m, uint8_t queue) 4139 { 4140 4141 KASSERT(m->a.queue == PQ_NONE && 4142 (m->a.flags & PGA_QUEUE_STATE_MASK) == 0, 4143 ("%s: page %p is already enqueued", __func__, m)); 4144 KASSERT(m->ref_count > 0, 4145 ("%s: page %p does not carry any references", __func__, m)); 4146 4147 m->a.queue = queue; 4148 if ((m->a.flags & PGA_REQUEUE) == 0) 4149 vm_page_aflag_set(m, PGA_REQUEUE); 4150 vm_page_pqbatch_submit(m, queue); 4151 } 4152 4153 /* 4154 * vm_page_free_prep: 4155 * 4156 * Prepares the given page to be put on the free list, 4157 * disassociating it from any VM object. The caller may return 4158 * the page to the free list only if this function returns true. 4159 * 4160 * The object, if it exists, must be locked, and then the page must 4161 * be xbusy. Otherwise the page must be not busied. A managed 4162 * page must be unmapped. 4163 */ 4164 static bool 4165 vm_page_free_prep(vm_page_t m) 4166 { 4167 4168 /* 4169 * Synchronize with threads that have dropped a reference to this 4170 * page. 4171 */ 4172 atomic_thread_fence_acq(); 4173 4174 #if defined(DIAGNOSTIC) && defined(PHYS_TO_DMAP) 4175 if (PMAP_HAS_DMAP && (m->flags & PG_ZERO) != 0) { 4176 uint64_t *p; 4177 int i; 4178 p = (uint64_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m)); 4179 for (i = 0; i < PAGE_SIZE / sizeof(uint64_t); i++, p++) 4180 KASSERT(*p == 0, ("vm_page_free_prep %p PG_ZERO %d %jx", 4181 m, i, (uintmax_t)*p)); 4182 } 4183 #endif 4184 KASSERT((m->flags & PG_NOFREE) == 0, 4185 ("%s: attempting to free a PG_NOFREE page", __func__)); 4186 if ((m->oflags & VPO_UNMANAGED) == 0) { 4187 KASSERT(!pmap_page_is_mapped(m), 4188 ("vm_page_free_prep: freeing mapped page %p", m)); 4189 KASSERT((m->a.flags & (PGA_EXECUTABLE | PGA_WRITEABLE)) == 0, 4190 ("vm_page_free_prep: mapping flags set in page %p", m)); 4191 } else { 4192 KASSERT(m->a.queue == PQ_NONE, 4193 ("vm_page_free_prep: unmanaged page %p is queued", m)); 4194 } 4195 VM_CNT_INC(v_tfree); 4196 4197 if (m->object != NULL) { 4198 vm_page_radix_remove(m); 4199 vm_page_free_object_prep(m); 4200 } else 4201 vm_page_assert_unbusied(m); 4202 4203 vm_page_busy_free(m); 4204 4205 /* 4206 * If fictitious remove object association and 4207 * return. 4208 */ 4209 if ((m->flags & PG_FICTITIOUS) != 0) { 4210 KASSERT(m->ref_count == 1, 4211 ("fictitious page %p is referenced", m)); 4212 KASSERT(m->a.queue == PQ_NONE, 4213 ("fictitious page %p is queued", m)); 4214 return (false); 4215 } 4216 4217 /* 4218 * Pages need not be dequeued before they are returned to the physical 4219 * memory allocator, but they must at least be marked for a deferred 4220 * dequeue. 4221 */ 4222 if ((m->oflags & VPO_UNMANAGED) == 0) 4223 vm_page_dequeue_deferred(m); 4224 4225 m->valid = 0; 4226 vm_page_undirty(m); 4227 4228 if (m->ref_count != 0) 4229 panic("vm_page_free_prep: page %p has references", m); 4230 4231 /* 4232 * Restore the default memory attribute to the page. 4233 */ 4234 if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT) 4235 pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT); 4236 4237 #if VM_NRESERVLEVEL > 0 4238 /* 4239 * Determine whether the page belongs to a reservation. If the page was 4240 * allocated from a per-CPU cache, it cannot belong to a reservation, so 4241 * as an optimization, we avoid the check in that case. 4242 */ 4243 if ((m->flags & PG_PCPU_CACHE) == 0 && vm_reserv_free_page(m)) 4244 return (false); 4245 #endif 4246 4247 return (true); 4248 } 4249 4250 /* 4251 * vm_page_free_toq: 4252 * 4253 * Returns the given page to the free list, disassociating it 4254 * from any VM object. 4255 * 4256 * The object must be locked. The page must be exclusively busied if it 4257 * belongs to an object. 4258 */ 4259 static void 4260 vm_page_free_toq(vm_page_t m) 4261 { 4262 struct vm_domain *vmd; 4263 uma_zone_t zone; 4264 4265 if (!vm_page_free_prep(m)) 4266 return; 4267 4268 vmd = vm_pagequeue_domain(m); 4269 zone = vmd->vmd_pgcache[m->pool].zone; 4270 if ((m->flags & PG_PCPU_CACHE) != 0 && zone != NULL) { 4271 uma_zfree(zone, m); 4272 return; 4273 } 4274 vm_domain_free_lock(vmd); 4275 vm_phys_free_pages(m, 0); 4276 vm_domain_free_unlock(vmd); 4277 vm_domain_freecnt_inc(vmd, 1); 4278 } 4279 4280 /* 4281 * vm_page_free_pages_toq: 4282 * 4283 * Returns a list of pages to the free list, disassociating it 4284 * from any VM object. In other words, this is equivalent to 4285 * calling vm_page_free_toq() for each page of a list of VM objects. 4286 */ 4287 int 4288 vm_page_free_pages_toq(struct spglist *free, bool update_wire_count) 4289 { 4290 vm_page_t m; 4291 int count; 4292 4293 if (SLIST_EMPTY(free)) 4294 return (0); 4295 4296 count = 0; 4297 while ((m = SLIST_FIRST(free)) != NULL) { 4298 count++; 4299 SLIST_REMOVE_HEAD(free, plinks.s.ss); 4300 vm_page_free_toq(m); 4301 } 4302 4303 if (update_wire_count) 4304 vm_wire_sub(count); 4305 return (count); 4306 } 4307 4308 /* 4309 * Mark this page as wired down. For managed pages, this prevents reclamation 4310 * by the page daemon, or when the containing object, if any, is destroyed. 4311 */ 4312 void 4313 vm_page_wire(vm_page_t m) 4314 { 4315 u_int old; 4316 4317 #ifdef INVARIANTS 4318 if (m->object != NULL && !vm_page_busied(m) && 4319 !vm_object_busied(m->object)) 4320 VM_OBJECT_ASSERT_LOCKED(m->object); 4321 #endif 4322 KASSERT((m->flags & PG_FICTITIOUS) == 0 || 4323 VPRC_WIRE_COUNT(m->ref_count) >= 1, 4324 ("vm_page_wire: fictitious page %p has zero wirings", m)); 4325 4326 old = atomic_fetchadd_int(&m->ref_count, 1); 4327 KASSERT(VPRC_WIRE_COUNT(old) != VPRC_WIRE_COUNT_MAX, 4328 ("vm_page_wire: counter overflow for page %p", m)); 4329 if (VPRC_WIRE_COUNT(old) == 0) { 4330 if ((m->oflags & VPO_UNMANAGED) == 0) 4331 vm_page_aflag_set(m, PGA_DEQUEUE); 4332 vm_wire_add(1); 4333 } 4334 } 4335 4336 /* 4337 * Attempt to wire a mapped page following a pmap lookup of that page. 4338 * This may fail if a thread is concurrently tearing down mappings of the page. 4339 * The transient failure is acceptable because it translates to the 4340 * failure of the caller pmap_extract_and_hold(), which should be then 4341 * followed by the vm_fault() fallback, see e.g. vm_fault_quick_hold_pages(). 4342 */ 4343 bool 4344 vm_page_wire_mapped(vm_page_t m) 4345 { 4346 u_int old; 4347 4348 old = atomic_load_int(&m->ref_count); 4349 do { 4350 KASSERT(old > 0, 4351 ("vm_page_wire_mapped: wiring unreferenced page %p", m)); 4352 if ((old & VPRC_BLOCKED) != 0) 4353 return (false); 4354 } while (!atomic_fcmpset_int(&m->ref_count, &old, old + 1)); 4355 4356 if (VPRC_WIRE_COUNT(old) == 0) { 4357 if ((m->oflags & VPO_UNMANAGED) == 0) 4358 vm_page_aflag_set(m, PGA_DEQUEUE); 4359 vm_wire_add(1); 4360 } 4361 return (true); 4362 } 4363 4364 /* 4365 * Release a wiring reference to a managed page. If the page still belongs to 4366 * an object, update its position in the page queues to reflect the reference. 4367 * If the wiring was the last reference to the page, free the page. 4368 */ 4369 static void 4370 vm_page_unwire_managed(vm_page_t m, uint8_t nqueue, bool noreuse) 4371 { 4372 u_int old; 4373 4374 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 4375 ("%s: page %p is unmanaged", __func__, m)); 4376 4377 /* 4378 * Update LRU state before releasing the wiring reference. 4379 * Use a release store when updating the reference count to 4380 * synchronize with vm_page_free_prep(). 4381 */ 4382 old = atomic_load_int(&m->ref_count); 4383 do { 4384 u_int count; 4385 4386 KASSERT(VPRC_WIRE_COUNT(old) > 0, 4387 ("vm_page_unwire: wire count underflow for page %p", m)); 4388 4389 count = old & ~VPRC_BLOCKED; 4390 if (count > VPRC_OBJREF + 1) { 4391 /* 4392 * The page has at least one other wiring reference. An 4393 * earlier iteration of this loop may have called 4394 * vm_page_release_toq() and cleared PGA_DEQUEUE, so 4395 * re-set it if necessary. 4396 */ 4397 if ((vm_page_astate_load(m).flags & PGA_DEQUEUE) == 0) 4398 vm_page_aflag_set(m, PGA_DEQUEUE); 4399 } else if (count == VPRC_OBJREF + 1) { 4400 /* 4401 * This is the last wiring. Clear PGA_DEQUEUE and 4402 * update the page's queue state to reflect the 4403 * reference. If the page does not belong to an object 4404 * (i.e., the VPRC_OBJREF bit is clear), we only need to 4405 * clear leftover queue state. 4406 */ 4407 vm_page_release_toq(m, nqueue, noreuse); 4408 } else if (count == 1) { 4409 vm_page_aflag_clear(m, PGA_DEQUEUE); 4410 } 4411 } while (!atomic_fcmpset_rel_int(&m->ref_count, &old, old - 1)); 4412 4413 if (VPRC_WIRE_COUNT(old) == 1) { 4414 vm_wire_sub(1); 4415 if (old == 1) 4416 vm_page_free(m); 4417 } 4418 } 4419 4420 /* 4421 * Release one wiring of the specified page, potentially allowing it to be 4422 * paged out. 4423 * 4424 * Only managed pages belonging to an object can be paged out. If the number 4425 * of wirings transitions to zero and the page is eligible for page out, then 4426 * the page is added to the specified paging queue. If the released wiring 4427 * represented the last reference to the page, the page is freed. 4428 */ 4429 void 4430 vm_page_unwire(vm_page_t m, uint8_t nqueue) 4431 { 4432 4433 KASSERT(nqueue < PQ_COUNT, 4434 ("vm_page_unwire: invalid queue %u request for page %p", 4435 nqueue, m)); 4436 4437 if ((m->oflags & VPO_UNMANAGED) != 0) { 4438 if (vm_page_unwire_noq(m) && m->ref_count == 0) 4439 vm_page_free(m); 4440 return; 4441 } 4442 vm_page_unwire_managed(m, nqueue, false); 4443 } 4444 4445 /* 4446 * Unwire a page without (re-)inserting it into a page queue. It is up 4447 * to the caller to enqueue, requeue, or free the page as appropriate. 4448 * In most cases involving managed pages, vm_page_unwire() should be used 4449 * instead. 4450 */ 4451 bool 4452 vm_page_unwire_noq(vm_page_t m) 4453 { 4454 u_int old; 4455 4456 old = vm_page_drop(m, 1); 4457 KASSERT(VPRC_WIRE_COUNT(old) != 0, 4458 ("%s: counter underflow for page %p", __func__, m)); 4459 KASSERT((m->flags & PG_FICTITIOUS) == 0 || VPRC_WIRE_COUNT(old) > 1, 4460 ("%s: missing ref on fictitious page %p", __func__, m)); 4461 4462 if (VPRC_WIRE_COUNT(old) > 1) 4463 return (false); 4464 if ((m->oflags & VPO_UNMANAGED) == 0) 4465 vm_page_aflag_clear(m, PGA_DEQUEUE); 4466 vm_wire_sub(1); 4467 return (true); 4468 } 4469 4470 /* 4471 * Ensure that the page ends up in the specified page queue. If the page is 4472 * active or being moved to the active queue, ensure that its act_count is 4473 * at least ACT_INIT but do not otherwise mess with it. 4474 */ 4475 static __always_inline void 4476 vm_page_mvqueue(vm_page_t m, const uint8_t nqueue, const uint16_t nflag) 4477 { 4478 vm_page_astate_t old, new; 4479 4480 KASSERT(m->ref_count > 0, 4481 ("%s: page %p does not carry any references", __func__, m)); 4482 KASSERT(nflag == PGA_REQUEUE || nflag == PGA_REQUEUE_HEAD, 4483 ("%s: invalid flags %x", __func__, nflag)); 4484 4485 if ((m->oflags & VPO_UNMANAGED) != 0 || vm_page_wired(m)) 4486 return; 4487 4488 old = vm_page_astate_load(m); 4489 do { 4490 if ((old.flags & PGA_DEQUEUE) != 0) 4491 break; 4492 new = old; 4493 new.flags &= ~PGA_QUEUE_OP_MASK; 4494 if (nqueue == PQ_ACTIVE) 4495 new.act_count = max(old.act_count, ACT_INIT); 4496 if (old.queue == nqueue) { 4497 /* 4498 * There is no need to requeue pages already in the 4499 * active queue. 4500 */ 4501 if (nqueue != PQ_ACTIVE || 4502 (old.flags & PGA_ENQUEUED) == 0) 4503 new.flags |= nflag; 4504 } else { 4505 new.flags |= nflag; 4506 new.queue = nqueue; 4507 } 4508 } while (!vm_page_pqstate_commit(m, &old, new)); 4509 } 4510 4511 /* 4512 * Put the specified page on the active list (if appropriate). 4513 */ 4514 void 4515 vm_page_activate(vm_page_t m) 4516 { 4517 4518 vm_page_mvqueue(m, PQ_ACTIVE, PGA_REQUEUE); 4519 } 4520 4521 /* 4522 * Move the specified page to the tail of the inactive queue, or requeue 4523 * the page if it is already in the inactive queue. 4524 */ 4525 void 4526 vm_page_deactivate(vm_page_t m) 4527 { 4528 4529 vm_page_mvqueue(m, PQ_INACTIVE, PGA_REQUEUE); 4530 } 4531 4532 void 4533 vm_page_deactivate_noreuse(vm_page_t m) 4534 { 4535 4536 vm_page_mvqueue(m, PQ_INACTIVE, PGA_REQUEUE_HEAD); 4537 } 4538 4539 /* 4540 * Put a page in the laundry, or requeue it if it is already there. 4541 */ 4542 void 4543 vm_page_launder(vm_page_t m) 4544 { 4545 4546 vm_page_mvqueue(m, PQ_LAUNDRY, PGA_REQUEUE); 4547 } 4548 4549 /* 4550 * Put a page in the PQ_UNSWAPPABLE holding queue. 4551 */ 4552 void 4553 vm_page_unswappable(vm_page_t m) 4554 { 4555 4556 VM_OBJECT_ASSERT_LOCKED(m->object); 4557 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 4558 ("page %p already unswappable", m)); 4559 4560 vm_page_dequeue(m); 4561 vm_page_enqueue(m, PQ_UNSWAPPABLE); 4562 } 4563 4564 /* 4565 * Release a page back to the page queues in preparation for unwiring. 4566 */ 4567 static void 4568 vm_page_release_toq(vm_page_t m, uint8_t nqueue, const bool noreuse) 4569 { 4570 vm_page_astate_t old, new; 4571 uint16_t nflag; 4572 4573 /* 4574 * Use a check of the valid bits to determine whether we should 4575 * accelerate reclamation of the page. The object lock might not be 4576 * held here, in which case the check is racy. At worst we will either 4577 * accelerate reclamation of a valid page and violate LRU, or 4578 * unnecessarily defer reclamation of an invalid page. 4579 * 4580 * If we were asked to not cache the page, place it near the head of the 4581 * inactive queue so that is reclaimed sooner. 4582 */ 4583 if (noreuse || vm_page_none_valid(m)) { 4584 nqueue = PQ_INACTIVE; 4585 nflag = PGA_REQUEUE_HEAD; 4586 } else { 4587 nflag = PGA_REQUEUE; 4588 } 4589 4590 old = vm_page_astate_load(m); 4591 do { 4592 new = old; 4593 4594 /* 4595 * If the page is already in the active queue and we are not 4596 * trying to accelerate reclamation, simply mark it as 4597 * referenced and avoid any queue operations. 4598 */ 4599 new.flags &= ~PGA_QUEUE_OP_MASK; 4600 if (nflag != PGA_REQUEUE_HEAD && old.queue == PQ_ACTIVE && 4601 (old.flags & PGA_ENQUEUED) != 0) 4602 new.flags |= PGA_REFERENCED; 4603 else { 4604 new.flags |= nflag; 4605 new.queue = nqueue; 4606 } 4607 } while (!vm_page_pqstate_commit(m, &old, new)); 4608 } 4609 4610 /* 4611 * Unwire a page and either attempt to free it or re-add it to the page queues. 4612 */ 4613 void 4614 vm_page_release(vm_page_t m, int flags) 4615 { 4616 vm_object_t object; 4617 4618 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 4619 ("vm_page_release: page %p is unmanaged", m)); 4620 4621 if ((flags & VPR_TRYFREE) != 0) { 4622 for (;;) { 4623 object = atomic_load_ptr(&m->object); 4624 if (object == NULL) 4625 break; 4626 /* Depends on type-stability. */ 4627 if (vm_page_busied(m) || !VM_OBJECT_TRYWLOCK(object)) 4628 break; 4629 if (object == m->object) { 4630 vm_page_release_locked(m, flags); 4631 VM_OBJECT_WUNLOCK(object); 4632 return; 4633 } 4634 VM_OBJECT_WUNLOCK(object); 4635 } 4636 } 4637 vm_page_unwire_managed(m, PQ_INACTIVE, flags != 0); 4638 } 4639 4640 /* See vm_page_release(). */ 4641 void 4642 vm_page_release_locked(vm_page_t m, int flags) 4643 { 4644 4645 VM_OBJECT_ASSERT_WLOCKED(m->object); 4646 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 4647 ("vm_page_release_locked: page %p is unmanaged", m)); 4648 4649 if (vm_page_unwire_noq(m)) { 4650 if ((flags & VPR_TRYFREE) != 0 && 4651 (m->object->ref_count == 0 || !pmap_page_is_mapped(m)) && 4652 m->dirty == 0 && vm_page_tryxbusy(m)) { 4653 /* 4654 * An unlocked lookup may have wired the page before the 4655 * busy lock was acquired, in which case the page must 4656 * not be freed. 4657 */ 4658 if (__predict_true(!vm_page_wired(m))) { 4659 vm_page_free(m); 4660 return; 4661 } 4662 vm_page_xunbusy(m); 4663 } else { 4664 vm_page_release_toq(m, PQ_INACTIVE, flags != 0); 4665 } 4666 } 4667 } 4668 4669 static bool 4670 vm_page_try_blocked_op(vm_page_t m, void (*op)(vm_page_t)) 4671 { 4672 u_int old; 4673 4674 KASSERT(m->object != NULL && (m->oflags & VPO_UNMANAGED) == 0, 4675 ("vm_page_try_blocked_op: page %p has no object", m)); 4676 KASSERT(vm_page_busied(m), 4677 ("vm_page_try_blocked_op: page %p is not busy", m)); 4678 VM_OBJECT_ASSERT_LOCKED(m->object); 4679 4680 old = atomic_load_int(&m->ref_count); 4681 do { 4682 KASSERT(old != 0, 4683 ("vm_page_try_blocked_op: page %p has no references", m)); 4684 KASSERT((old & VPRC_BLOCKED) == 0, 4685 ("vm_page_try_blocked_op: page %p blocks wirings", m)); 4686 if (VPRC_WIRE_COUNT(old) != 0) 4687 return (false); 4688 } while (!atomic_fcmpset_int(&m->ref_count, &old, old | VPRC_BLOCKED)); 4689 4690 (op)(m); 4691 4692 /* 4693 * If the object is read-locked, new wirings may be created via an 4694 * object lookup. 4695 */ 4696 old = vm_page_drop(m, VPRC_BLOCKED); 4697 KASSERT(!VM_OBJECT_WOWNED(m->object) || 4698 old == (VPRC_BLOCKED | VPRC_OBJREF), 4699 ("vm_page_try_blocked_op: unexpected refcount value %u for %p", 4700 old, m)); 4701 return (true); 4702 } 4703 4704 /* 4705 * Atomically check for wirings and remove all mappings of the page. 4706 */ 4707 bool 4708 vm_page_try_remove_all(vm_page_t m) 4709 { 4710 4711 return (vm_page_try_blocked_op(m, pmap_remove_all)); 4712 } 4713 4714 /* 4715 * Atomically check for wirings and remove all writeable mappings of the page. 4716 */ 4717 bool 4718 vm_page_try_remove_write(vm_page_t m) 4719 { 4720 4721 return (vm_page_try_blocked_op(m, pmap_remove_write)); 4722 } 4723 4724 /* 4725 * vm_page_advise 4726 * 4727 * Apply the specified advice to the given page. 4728 */ 4729 void 4730 vm_page_advise(vm_page_t m, int advice) 4731 { 4732 4733 VM_OBJECT_ASSERT_WLOCKED(m->object); 4734 vm_page_assert_xbusied(m); 4735 4736 if (advice == MADV_FREE) 4737 /* 4738 * Mark the page clean. This will allow the page to be freed 4739 * without first paging it out. MADV_FREE pages are often 4740 * quickly reused by malloc(3), so we do not do anything that 4741 * would result in a page fault on a later access. 4742 */ 4743 vm_page_undirty(m); 4744 else if (advice != MADV_DONTNEED) { 4745 if (advice == MADV_WILLNEED) 4746 vm_page_activate(m); 4747 return; 4748 } 4749 4750 if (advice != MADV_FREE && m->dirty == 0 && pmap_is_modified(m)) 4751 vm_page_dirty(m); 4752 4753 /* 4754 * Clear any references to the page. Otherwise, the page daemon will 4755 * immediately reactivate the page. 4756 */ 4757 vm_page_aflag_clear(m, PGA_REFERENCED); 4758 4759 /* 4760 * Place clean pages near the head of the inactive queue rather than 4761 * the tail, thus defeating the queue's LRU operation and ensuring that 4762 * the page will be reused quickly. Dirty pages not already in the 4763 * laundry are moved there. 4764 */ 4765 if (m->dirty == 0) 4766 vm_page_deactivate_noreuse(m); 4767 else if (!vm_page_in_laundry(m)) 4768 vm_page_launder(m); 4769 } 4770 4771 /* 4772 * vm_page_grab_release 4773 * 4774 * Helper routine for grab functions to release busy on return. 4775 */ 4776 static inline void 4777 vm_page_grab_release(vm_page_t m, int allocflags) 4778 { 4779 4780 if ((allocflags & VM_ALLOC_NOBUSY) != 0) { 4781 if ((allocflags & VM_ALLOC_IGN_SBUSY) != 0) 4782 vm_page_sunbusy(m); 4783 else 4784 vm_page_xunbusy(m); 4785 } 4786 } 4787 4788 /* 4789 * vm_page_grab_sleep 4790 * 4791 * Sleep for busy according to VM_ALLOC_ parameters. Returns true 4792 * if the caller should retry and false otherwise. 4793 * 4794 * If the object is locked on entry the object will be unlocked with 4795 * false returns and still locked but possibly having been dropped 4796 * with true returns. 4797 */ 4798 static bool 4799 vm_page_grab_sleep(vm_object_t object, vm_page_t m, vm_pindex_t pindex, 4800 const char *wmesg, int allocflags, bool locked) 4801 { 4802 4803 if ((allocflags & VM_ALLOC_NOWAIT) != 0) 4804 return (false); 4805 4806 /* 4807 * Reference the page before unlocking and sleeping so that 4808 * the page daemon is less likely to reclaim it. 4809 */ 4810 if (locked && (allocflags & VM_ALLOC_NOCREAT) == 0) 4811 vm_page_reference(m); 4812 4813 if (_vm_page_busy_sleep(object, m, pindex, wmesg, allocflags, locked) && 4814 locked) 4815 VM_OBJECT_WLOCK(object); 4816 if ((allocflags & VM_ALLOC_WAITFAIL) != 0) 4817 return (false); 4818 4819 return (true); 4820 } 4821 4822 /* 4823 * Assert that the grab flags are valid. 4824 */ 4825 static inline void 4826 vm_page_grab_check(int allocflags) 4827 { 4828 4829 KASSERT((allocflags & VM_ALLOC_NOBUSY) == 0 || 4830 (allocflags & VM_ALLOC_WIRED) != 0, 4831 ("vm_page_grab*: the pages must be busied or wired")); 4832 4833 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || 4834 (allocflags & VM_ALLOC_IGN_SBUSY) != 0, 4835 ("vm_page_grab*: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch")); 4836 } 4837 4838 /* 4839 * Calculate the page allocation flags for grab. 4840 */ 4841 static inline int 4842 vm_page_grab_pflags(int allocflags) 4843 { 4844 int pflags; 4845 4846 pflags = allocflags & 4847 ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL | 4848 VM_ALLOC_NOBUSY | VM_ALLOC_IGN_SBUSY); 4849 if ((allocflags & VM_ALLOC_NOWAIT) == 0) 4850 pflags |= VM_ALLOC_WAITFAIL; 4851 if ((allocflags & VM_ALLOC_IGN_SBUSY) != 0) 4852 pflags |= VM_ALLOC_SBUSY; 4853 4854 return (pflags); 4855 } 4856 4857 /* 4858 * Grab a page, waiting until we are waken up due to the page 4859 * changing state. We keep on waiting, if the page continues 4860 * to be in the object. If the page doesn't exist, first allocate it 4861 * and then conditionally zero it. 4862 * 4863 * This routine may sleep. 4864 * 4865 * The object must be locked on entry. The lock will, however, be released 4866 * and reacquired if the routine sleeps. 4867 */ 4868 vm_page_t 4869 vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags) 4870 { 4871 vm_page_t m; 4872 4873 VM_OBJECT_ASSERT_WLOCKED(object); 4874 vm_page_grab_check(allocflags); 4875 4876 retrylookup: 4877 if ((m = vm_page_lookup(object, pindex)) != NULL) { 4878 if (!vm_page_tryacquire(m, allocflags)) { 4879 if (vm_page_grab_sleep(object, m, pindex, "pgrbwt", 4880 allocflags, true)) 4881 goto retrylookup; 4882 return (NULL); 4883 } 4884 goto out; 4885 } 4886 if ((allocflags & VM_ALLOC_NOCREAT) != 0) 4887 return (NULL); 4888 m = vm_page_alloc(object, pindex, vm_page_grab_pflags(allocflags)); 4889 if (m == NULL) { 4890 if ((allocflags & (VM_ALLOC_NOWAIT | VM_ALLOC_WAITFAIL)) != 0) 4891 return (NULL); 4892 goto retrylookup; 4893 } 4894 if (allocflags & VM_ALLOC_ZERO && (m->flags & PG_ZERO) == 0) 4895 pmap_zero_page(m); 4896 4897 out: 4898 vm_page_grab_release(m, allocflags); 4899 4900 return (m); 4901 } 4902 4903 /* 4904 * Attempt to validate a page, locklessly acquiring it if necessary, given a 4905 * (object, pindex) tuple and either an invalided page or NULL. The resulting 4906 * page will be validated against the identity tuple, and busied or wired as 4907 * requested. A NULL page returned guarantees that the page was not in radix at 4908 * the time of the call but callers must perform higher level synchronization or 4909 * retry the operation under a lock if they require an atomic answer. This is 4910 * the only lock free validation routine, other routines can depend on the 4911 * resulting page state. 4912 * 4913 * The return value PAGE_NOT_ACQUIRED indicates that the operation failed due to 4914 * caller flags. 4915 */ 4916 #define PAGE_NOT_ACQUIRED ((vm_page_t)1) 4917 static vm_page_t 4918 vm_page_acquire_unlocked(vm_object_t object, vm_pindex_t pindex, vm_page_t m, 4919 int allocflags) 4920 { 4921 if (m == NULL) 4922 m = vm_page_lookup_unlocked(object, pindex); 4923 for (; m != NULL; m = vm_page_lookup_unlocked(object, pindex)) { 4924 if (vm_page_trybusy(m, allocflags)) { 4925 if (m->object == object && m->pindex == pindex) { 4926 if ((allocflags & VM_ALLOC_WIRED) != 0) 4927 vm_page_wire(m); 4928 vm_page_grab_release(m, allocflags); 4929 break; 4930 } 4931 /* relookup. */ 4932 vm_page_busy_release(m); 4933 cpu_spinwait(); 4934 continue; 4935 } 4936 if (!vm_page_grab_sleep(object, m, pindex, "pgnslp", 4937 allocflags, false)) 4938 return (PAGE_NOT_ACQUIRED); 4939 } 4940 return (m); 4941 } 4942 4943 /* 4944 * Try to locklessly grab a page and fall back to the object lock if NOCREAT 4945 * is not set. 4946 */ 4947 vm_page_t 4948 vm_page_grab_unlocked(vm_object_t object, vm_pindex_t pindex, int allocflags) 4949 { 4950 vm_page_t m; 4951 4952 vm_page_grab_check(allocflags); 4953 m = vm_page_acquire_unlocked(object, pindex, NULL, allocflags); 4954 if (m == PAGE_NOT_ACQUIRED) 4955 return (NULL); 4956 if (m != NULL) 4957 return (m); 4958 4959 /* 4960 * The radix lockless lookup should never return a false negative 4961 * errors. If the user specifies NOCREAT they are guaranteed there 4962 * was no page present at the instant of the call. A NOCREAT caller 4963 * must handle create races gracefully. 4964 */ 4965 if ((allocflags & VM_ALLOC_NOCREAT) != 0) 4966 return (NULL); 4967 4968 VM_OBJECT_WLOCK(object); 4969 m = vm_page_grab(object, pindex, allocflags); 4970 VM_OBJECT_WUNLOCK(object); 4971 4972 return (m); 4973 } 4974 4975 /* 4976 * Grab a page and make it valid, paging in if necessary. Pages missing from 4977 * their pager are zero filled and validated. If a VM_ALLOC_COUNT is supplied 4978 * and the page is not valid as many as VM_INITIAL_PAGEIN pages can be brought 4979 * in simultaneously. Additional pages will be left on a paging queue but 4980 * will neither be wired nor busy regardless of allocflags. 4981 */ 4982 int 4983 vm_page_grab_valid(vm_page_t *mp, vm_object_t object, vm_pindex_t pindex, int allocflags) 4984 { 4985 vm_page_t m; 4986 vm_page_t ma[VM_INITIAL_PAGEIN]; 4987 int after, i, pflags, rv; 4988 4989 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || 4990 (allocflags & VM_ALLOC_IGN_SBUSY) != 0, 4991 ("vm_page_grab_valid: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch")); 4992 KASSERT((allocflags & 4993 (VM_ALLOC_NOWAIT | VM_ALLOC_WAITFAIL | VM_ALLOC_ZERO)) == 0, 4994 ("vm_page_grab_valid: Invalid flags 0x%X", allocflags)); 4995 VM_OBJECT_ASSERT_WLOCKED(object); 4996 pflags = allocflags & ~(VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY | 4997 VM_ALLOC_WIRED | VM_ALLOC_IGN_SBUSY); 4998 pflags |= VM_ALLOC_WAITFAIL; 4999 5000 retrylookup: 5001 if ((m = vm_page_lookup(object, pindex)) != NULL) { 5002 /* 5003 * If the page is fully valid it can only become invalid 5004 * with the object lock held. If it is not valid it can 5005 * become valid with the busy lock held. Therefore, we 5006 * may unnecessarily lock the exclusive busy here if we 5007 * race with I/O completion not using the object lock. 5008 * However, we will not end up with an invalid page and a 5009 * shared lock. 5010 */ 5011 if (!vm_page_trybusy(m, 5012 vm_page_all_valid(m) ? allocflags : 0)) { 5013 (void)vm_page_grab_sleep(object, m, pindex, "pgrbwt", 5014 allocflags, true); 5015 goto retrylookup; 5016 } 5017 if (vm_page_all_valid(m)) 5018 goto out; 5019 if ((allocflags & VM_ALLOC_NOCREAT) != 0) { 5020 vm_page_busy_release(m); 5021 *mp = NULL; 5022 return (VM_PAGER_FAIL); 5023 } 5024 } else if ((allocflags & VM_ALLOC_NOCREAT) != 0) { 5025 *mp = NULL; 5026 return (VM_PAGER_FAIL); 5027 } else if ((m = vm_page_alloc(object, pindex, pflags)) == NULL) { 5028 if (!vm_pager_can_alloc_page(object, pindex)) { 5029 *mp = NULL; 5030 return (VM_PAGER_AGAIN); 5031 } 5032 goto retrylookup; 5033 } 5034 5035 vm_page_assert_xbusied(m); 5036 if (vm_pager_has_page(object, pindex, NULL, &after)) { 5037 after = MIN(after, VM_INITIAL_PAGEIN); 5038 after = MIN(after, allocflags >> VM_ALLOC_COUNT_SHIFT); 5039 after = MAX(after, 1); 5040 ma[0] = m; 5041 for (i = 1; i < after; i++) { 5042 if ((ma[i] = vm_page_next(ma[i - 1])) != NULL) { 5043 if (vm_page_any_valid(ma[i]) || 5044 !vm_page_tryxbusy(ma[i])) 5045 break; 5046 } else { 5047 ma[i] = vm_page_alloc(object, m->pindex + i, 5048 VM_ALLOC_NORMAL); 5049 if (ma[i] == NULL) 5050 break; 5051 } 5052 } 5053 after = i; 5054 vm_object_pip_add(object, after); 5055 VM_OBJECT_WUNLOCK(object); 5056 rv = vm_pager_get_pages(object, ma, after, NULL, NULL); 5057 VM_OBJECT_WLOCK(object); 5058 vm_object_pip_wakeupn(object, after); 5059 /* Pager may have replaced a page. */ 5060 m = ma[0]; 5061 if (rv != VM_PAGER_OK) { 5062 for (i = 0; i < after; i++) { 5063 if (!vm_page_wired(ma[i])) 5064 vm_page_free(ma[i]); 5065 else 5066 vm_page_xunbusy(ma[i]); 5067 } 5068 *mp = NULL; 5069 return (rv); 5070 } 5071 for (i = 1; i < after; i++) 5072 vm_page_readahead_finish(ma[i]); 5073 MPASS(vm_page_all_valid(m)); 5074 } else { 5075 vm_page_zero_invalid(m, TRUE); 5076 } 5077 out: 5078 if ((allocflags & VM_ALLOC_WIRED) != 0) 5079 vm_page_wire(m); 5080 if ((allocflags & VM_ALLOC_SBUSY) != 0 && vm_page_xbusied(m)) 5081 vm_page_busy_downgrade(m); 5082 else if ((allocflags & VM_ALLOC_NOBUSY) != 0) 5083 vm_page_busy_release(m); 5084 *mp = m; 5085 return (VM_PAGER_OK); 5086 } 5087 5088 /* 5089 * Locklessly grab a valid page. If the page is not valid or not yet 5090 * allocated this will fall back to the object lock method. 5091 */ 5092 int 5093 vm_page_grab_valid_unlocked(vm_page_t *mp, vm_object_t object, 5094 vm_pindex_t pindex, int allocflags) 5095 { 5096 vm_page_t m; 5097 int flags; 5098 int error; 5099 5100 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || 5101 (allocflags & VM_ALLOC_IGN_SBUSY) != 0, 5102 ("vm_page_grab_valid_unlocked: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY " 5103 "mismatch")); 5104 KASSERT((allocflags & 5105 (VM_ALLOC_NOWAIT | VM_ALLOC_WAITFAIL | VM_ALLOC_ZERO)) == 0, 5106 ("vm_page_grab_valid_unlocked: Invalid flags 0x%X", allocflags)); 5107 5108 /* 5109 * Attempt a lockless lookup and busy. We need at least an sbusy 5110 * before we can inspect the valid field and return a wired page. 5111 */ 5112 flags = allocflags & ~(VM_ALLOC_NOBUSY | VM_ALLOC_WIRED); 5113 vm_page_grab_check(flags); 5114 m = vm_page_acquire_unlocked(object, pindex, NULL, flags); 5115 if (m == PAGE_NOT_ACQUIRED) 5116 return (VM_PAGER_FAIL); 5117 if (m != NULL) { 5118 if (vm_page_all_valid(m)) { 5119 if ((allocflags & VM_ALLOC_WIRED) != 0) 5120 vm_page_wire(m); 5121 vm_page_grab_release(m, allocflags); 5122 *mp = m; 5123 return (VM_PAGER_OK); 5124 } 5125 vm_page_busy_release(m); 5126 } 5127 if ((allocflags & VM_ALLOC_NOCREAT) != 0) { 5128 *mp = NULL; 5129 return (VM_PAGER_FAIL); 5130 } 5131 VM_OBJECT_WLOCK(object); 5132 error = vm_page_grab_valid(mp, object, pindex, allocflags); 5133 VM_OBJECT_WUNLOCK(object); 5134 5135 return (error); 5136 } 5137 5138 /* 5139 * Return the specified range of pages from the given object. For each 5140 * page offset within the range, if a page already exists within the object 5141 * at that offset and it is busy, then wait for it to change state. If, 5142 * instead, the page doesn't exist, then allocate it. 5143 * 5144 * The caller must always specify an allocation class. 5145 * 5146 * allocation classes: 5147 * VM_ALLOC_NORMAL normal process request 5148 * VM_ALLOC_SYSTEM system *really* needs the pages 5149 * 5150 * The caller must always specify that the pages are to be busied and/or 5151 * wired. 5152 * 5153 * optional allocation flags: 5154 * VM_ALLOC_IGN_SBUSY do not sleep on soft busy pages 5155 * VM_ALLOC_NOBUSY do not exclusive busy the page 5156 * VM_ALLOC_NOWAIT do not sleep 5157 * VM_ALLOC_SBUSY set page to sbusy state 5158 * VM_ALLOC_WIRED wire the pages 5159 * VM_ALLOC_ZERO zero and validate any invalid pages 5160 * 5161 * If VM_ALLOC_NOWAIT is not specified, this routine may sleep. Otherwise, it 5162 * may return a partial prefix of the requested range. 5163 */ 5164 int 5165 vm_page_grab_pages(vm_object_t object, vm_pindex_t pindex, int allocflags, 5166 vm_page_t *ma, int count) 5167 { 5168 vm_page_t m, mpred; 5169 int pflags; 5170 int i; 5171 5172 VM_OBJECT_ASSERT_WLOCKED(object); 5173 KASSERT(((u_int)allocflags >> VM_ALLOC_COUNT_SHIFT) == 0, 5174 ("vm_page_grap_pages: VM_ALLOC_COUNT() is not allowed")); 5175 KASSERT(count > 0, 5176 ("vm_page_grab_pages: invalid page count %d", count)); 5177 vm_page_grab_check(allocflags); 5178 5179 pflags = vm_page_grab_pflags(allocflags); 5180 i = 0; 5181 retrylookup: 5182 m = vm_page_mpred(object, pindex + i); 5183 if (m == NULL || m->pindex != pindex + i) { 5184 mpred = m; 5185 m = NULL; 5186 } else 5187 mpred = TAILQ_PREV(m, pglist, listq); 5188 for (; i < count; i++) { 5189 if (m != NULL) { 5190 if (!vm_page_tryacquire(m, allocflags)) { 5191 if (vm_page_grab_sleep(object, m, pindex + i, 5192 "grbmaw", allocflags, true)) 5193 goto retrylookup; 5194 break; 5195 } 5196 } else { 5197 if ((allocflags & VM_ALLOC_NOCREAT) != 0) 5198 break; 5199 m = vm_page_alloc_after(object, pindex + i, 5200 pflags | VM_ALLOC_COUNT(count - i), mpred); 5201 if (m == NULL) { 5202 if ((allocflags & (VM_ALLOC_NOWAIT | 5203 VM_ALLOC_WAITFAIL)) != 0) 5204 break; 5205 goto retrylookup; 5206 } 5207 } 5208 if (vm_page_none_valid(m) && 5209 (allocflags & VM_ALLOC_ZERO) != 0) { 5210 if ((m->flags & PG_ZERO) == 0) 5211 pmap_zero_page(m); 5212 vm_page_valid(m); 5213 } 5214 vm_page_grab_release(m, allocflags); 5215 ma[i] = mpred = m; 5216 m = vm_page_next(m); 5217 } 5218 return (i); 5219 } 5220 5221 /* 5222 * Unlocked variant of vm_page_grab_pages(). This accepts the same flags 5223 * and will fall back to the locked variant to handle allocation. 5224 */ 5225 int 5226 vm_page_grab_pages_unlocked(vm_object_t object, vm_pindex_t pindex, 5227 int allocflags, vm_page_t *ma, int count) 5228 { 5229 vm_page_t m; 5230 int flags; 5231 int i; 5232 5233 KASSERT(count > 0, 5234 ("vm_page_grab_pages_unlocked: invalid page count %d", count)); 5235 vm_page_grab_check(allocflags); 5236 5237 /* 5238 * Modify flags for lockless acquire to hold the page until we 5239 * set it valid if necessary. 5240 */ 5241 flags = allocflags & ~VM_ALLOC_NOBUSY; 5242 vm_page_grab_check(flags); 5243 m = NULL; 5244 for (i = 0; i < count; i++, pindex++) { 5245 /* 5246 * We may see a false NULL here because the previous page has 5247 * been removed or just inserted and the list is loaded without 5248 * barriers. Switch to radix to verify. 5249 */ 5250 if (m == NULL || QMD_IS_TRASHED(m) || m->pindex != pindex || 5251 atomic_load_ptr(&m->object) != object) { 5252 /* 5253 * This guarantees the result is instantaneously 5254 * correct. 5255 */ 5256 m = NULL; 5257 } 5258 m = vm_page_acquire_unlocked(object, pindex, m, flags); 5259 if (m == PAGE_NOT_ACQUIRED) 5260 return (i); 5261 if (m == NULL) 5262 break; 5263 if ((flags & VM_ALLOC_ZERO) != 0 && vm_page_none_valid(m)) { 5264 if ((m->flags & PG_ZERO) == 0) 5265 pmap_zero_page(m); 5266 vm_page_valid(m); 5267 } 5268 /* m will still be wired or busy according to flags. */ 5269 vm_page_grab_release(m, allocflags); 5270 ma[i] = m; 5271 m = TAILQ_NEXT(m, listq); 5272 } 5273 if (i == count || (allocflags & VM_ALLOC_NOCREAT) != 0) 5274 return (i); 5275 count -= i; 5276 VM_OBJECT_WLOCK(object); 5277 i += vm_page_grab_pages(object, pindex, allocflags, &ma[i], count); 5278 VM_OBJECT_WUNLOCK(object); 5279 5280 return (i); 5281 } 5282 5283 /* 5284 * Mapping function for valid or dirty bits in a page. 5285 * 5286 * Inputs are required to range within a page. 5287 */ 5288 vm_page_bits_t 5289 vm_page_bits(int base, int size) 5290 { 5291 int first_bit; 5292 int last_bit; 5293 5294 KASSERT( 5295 base + size <= PAGE_SIZE, 5296 ("vm_page_bits: illegal base/size %d/%d", base, size) 5297 ); 5298 5299 if (size == 0) /* handle degenerate case */ 5300 return (0); 5301 5302 first_bit = base >> DEV_BSHIFT; 5303 last_bit = (base + size - 1) >> DEV_BSHIFT; 5304 5305 return (((vm_page_bits_t)2 << last_bit) - 5306 ((vm_page_bits_t)1 << first_bit)); 5307 } 5308 5309 void 5310 vm_page_bits_set(vm_page_t m, vm_page_bits_t *bits, vm_page_bits_t set) 5311 { 5312 5313 #if PAGE_SIZE == 32768 5314 atomic_set_64((uint64_t *)bits, set); 5315 #elif PAGE_SIZE == 16384 5316 atomic_set_32((uint32_t *)bits, set); 5317 #elif (PAGE_SIZE == 8192) && defined(atomic_set_16) 5318 atomic_set_16((uint16_t *)bits, set); 5319 #elif (PAGE_SIZE == 4096) && defined(atomic_set_8) 5320 atomic_set_8((uint8_t *)bits, set); 5321 #else /* PAGE_SIZE <= 8192 */ 5322 uintptr_t addr; 5323 int shift; 5324 5325 addr = (uintptr_t)bits; 5326 /* 5327 * Use a trick to perform a 32-bit atomic on the 5328 * containing aligned word, to not depend on the existence 5329 * of atomic_{set, clear}_{8, 16}. 5330 */ 5331 shift = addr & (sizeof(uint32_t) - 1); 5332 #if BYTE_ORDER == BIG_ENDIAN 5333 shift = (sizeof(uint32_t) - sizeof(vm_page_bits_t) - shift) * NBBY; 5334 #else 5335 shift *= NBBY; 5336 #endif 5337 addr &= ~(sizeof(uint32_t) - 1); 5338 atomic_set_32((uint32_t *)addr, set << shift); 5339 #endif /* PAGE_SIZE */ 5340 } 5341 5342 static inline void 5343 vm_page_bits_clear(vm_page_t m, vm_page_bits_t *bits, vm_page_bits_t clear) 5344 { 5345 5346 #if PAGE_SIZE == 32768 5347 atomic_clear_64((uint64_t *)bits, clear); 5348 #elif PAGE_SIZE == 16384 5349 atomic_clear_32((uint32_t *)bits, clear); 5350 #elif (PAGE_SIZE == 8192) && defined(atomic_clear_16) 5351 atomic_clear_16((uint16_t *)bits, clear); 5352 #elif (PAGE_SIZE == 4096) && defined(atomic_clear_8) 5353 atomic_clear_8((uint8_t *)bits, clear); 5354 #else /* PAGE_SIZE <= 8192 */ 5355 uintptr_t addr; 5356 int shift; 5357 5358 addr = (uintptr_t)bits; 5359 /* 5360 * Use a trick to perform a 32-bit atomic on the 5361 * containing aligned word, to not depend on the existence 5362 * of atomic_{set, clear}_{8, 16}. 5363 */ 5364 shift = addr & (sizeof(uint32_t) - 1); 5365 #if BYTE_ORDER == BIG_ENDIAN 5366 shift = (sizeof(uint32_t) - sizeof(vm_page_bits_t) - shift) * NBBY; 5367 #else 5368 shift *= NBBY; 5369 #endif 5370 addr &= ~(sizeof(uint32_t) - 1); 5371 atomic_clear_32((uint32_t *)addr, clear << shift); 5372 #endif /* PAGE_SIZE */ 5373 } 5374 5375 static inline vm_page_bits_t 5376 vm_page_bits_swap(vm_page_t m, vm_page_bits_t *bits, vm_page_bits_t newbits) 5377 { 5378 #if PAGE_SIZE == 32768 5379 uint64_t old; 5380 5381 old = *bits; 5382 while (atomic_fcmpset_64(bits, &old, newbits) == 0); 5383 return (old); 5384 #elif PAGE_SIZE == 16384 5385 uint32_t old; 5386 5387 old = *bits; 5388 while (atomic_fcmpset_32(bits, &old, newbits) == 0); 5389 return (old); 5390 #elif (PAGE_SIZE == 8192) && defined(atomic_fcmpset_16) 5391 uint16_t old; 5392 5393 old = *bits; 5394 while (atomic_fcmpset_16(bits, &old, newbits) == 0); 5395 return (old); 5396 #elif (PAGE_SIZE == 4096) && defined(atomic_fcmpset_8) 5397 uint8_t old; 5398 5399 old = *bits; 5400 while (atomic_fcmpset_8(bits, &old, newbits) == 0); 5401 return (old); 5402 #else /* PAGE_SIZE <= 4096*/ 5403 uintptr_t addr; 5404 uint32_t old, new, mask; 5405 int shift; 5406 5407 addr = (uintptr_t)bits; 5408 /* 5409 * Use a trick to perform a 32-bit atomic on the 5410 * containing aligned word, to not depend on the existence 5411 * of atomic_{set, swap, clear}_{8, 16}. 5412 */ 5413 shift = addr & (sizeof(uint32_t) - 1); 5414 #if BYTE_ORDER == BIG_ENDIAN 5415 shift = (sizeof(uint32_t) - sizeof(vm_page_bits_t) - shift) * NBBY; 5416 #else 5417 shift *= NBBY; 5418 #endif 5419 addr &= ~(sizeof(uint32_t) - 1); 5420 mask = VM_PAGE_BITS_ALL << shift; 5421 5422 old = *bits; 5423 do { 5424 new = old & ~mask; 5425 new |= newbits << shift; 5426 } while (atomic_fcmpset_32((uint32_t *)addr, &old, new) == 0); 5427 return (old >> shift); 5428 #endif /* PAGE_SIZE */ 5429 } 5430 5431 /* 5432 * vm_page_set_valid_range: 5433 * 5434 * Sets portions of a page valid. The arguments are expected 5435 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive 5436 * of any partial chunks touched by the range. The invalid portion of 5437 * such chunks will be zeroed. 5438 * 5439 * (base + size) must be less then or equal to PAGE_SIZE. 5440 */ 5441 void 5442 vm_page_set_valid_range(vm_page_t m, int base, int size) 5443 { 5444 int endoff, frag; 5445 vm_page_bits_t pagebits; 5446 5447 vm_page_assert_busied(m); 5448 if (size == 0) /* handle degenerate case */ 5449 return; 5450 5451 /* 5452 * If the base is not DEV_BSIZE aligned and the valid 5453 * bit is clear, we have to zero out a portion of the 5454 * first block. 5455 */ 5456 if ((frag = rounddown2(base, DEV_BSIZE)) != base && 5457 (m->valid & (1 << (base >> DEV_BSHIFT))) == 0) 5458 pmap_zero_page_area(m, frag, base - frag); 5459 5460 /* 5461 * If the ending offset is not DEV_BSIZE aligned and the 5462 * valid bit is clear, we have to zero out a portion of 5463 * the last block. 5464 */ 5465 endoff = base + size; 5466 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && 5467 (m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0) 5468 pmap_zero_page_area(m, endoff, 5469 DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); 5470 5471 /* 5472 * Assert that no previously invalid block that is now being validated 5473 * is already dirty. 5474 */ 5475 KASSERT((~m->valid & vm_page_bits(base, size) & m->dirty) == 0, 5476 ("vm_page_set_valid_range: page %p is dirty", m)); 5477 5478 /* 5479 * Set valid bits inclusive of any overlap. 5480 */ 5481 pagebits = vm_page_bits(base, size); 5482 if (vm_page_xbusied(m)) 5483 m->valid |= pagebits; 5484 else 5485 vm_page_bits_set(m, &m->valid, pagebits); 5486 } 5487 5488 /* 5489 * Set the page dirty bits and free the invalid swap space if 5490 * present. Returns the previous dirty bits. 5491 */ 5492 vm_page_bits_t 5493 vm_page_set_dirty(vm_page_t m) 5494 { 5495 vm_page_bits_t old; 5496 5497 VM_PAGE_OBJECT_BUSY_ASSERT(m); 5498 5499 if (vm_page_xbusied(m) && !pmap_page_is_write_mapped(m)) { 5500 old = m->dirty; 5501 m->dirty = VM_PAGE_BITS_ALL; 5502 } else 5503 old = vm_page_bits_swap(m, &m->dirty, VM_PAGE_BITS_ALL); 5504 if (old == 0 && (m->a.flags & PGA_SWAP_SPACE) != 0) 5505 vm_pager_page_unswapped(m); 5506 5507 return (old); 5508 } 5509 5510 /* 5511 * Clear the given bits from the specified page's dirty field. 5512 */ 5513 static __inline void 5514 vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits) 5515 { 5516 5517 vm_page_assert_busied(m); 5518 5519 /* 5520 * If the page is xbusied and not write mapped we are the 5521 * only thread that can modify dirty bits. Otherwise, The pmap 5522 * layer can call vm_page_dirty() without holding a distinguished 5523 * lock. The combination of page busy and atomic operations 5524 * suffice to guarantee consistency of the page dirty field. 5525 */ 5526 if (vm_page_xbusied(m) && !pmap_page_is_write_mapped(m)) 5527 m->dirty &= ~pagebits; 5528 else 5529 vm_page_bits_clear(m, &m->dirty, pagebits); 5530 } 5531 5532 /* 5533 * vm_page_set_validclean: 5534 * 5535 * Sets portions of a page valid and clean. The arguments are expected 5536 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive 5537 * of any partial chunks touched by the range. The invalid portion of 5538 * such chunks will be zero'd. 5539 * 5540 * (base + size) must be less then or equal to PAGE_SIZE. 5541 */ 5542 void 5543 vm_page_set_validclean(vm_page_t m, int base, int size) 5544 { 5545 vm_page_bits_t oldvalid, pagebits; 5546 int endoff, frag; 5547 5548 vm_page_assert_busied(m); 5549 if (size == 0) /* handle degenerate case */ 5550 return; 5551 5552 /* 5553 * If the base is not DEV_BSIZE aligned and the valid 5554 * bit is clear, we have to zero out a portion of the 5555 * first block. 5556 */ 5557 if ((frag = rounddown2(base, DEV_BSIZE)) != base && 5558 (m->valid & ((vm_page_bits_t)1 << (base >> DEV_BSHIFT))) == 0) 5559 pmap_zero_page_area(m, frag, base - frag); 5560 5561 /* 5562 * If the ending offset is not DEV_BSIZE aligned and the 5563 * valid bit is clear, we have to zero out a portion of 5564 * the last block. 5565 */ 5566 endoff = base + size; 5567 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && 5568 (m->valid & ((vm_page_bits_t)1 << (endoff >> DEV_BSHIFT))) == 0) 5569 pmap_zero_page_area(m, endoff, 5570 DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); 5571 5572 /* 5573 * Set valid, clear dirty bits. If validating the entire 5574 * page we can safely clear the pmap modify bit. We also 5575 * use this opportunity to clear the PGA_NOSYNC flag. If a process 5576 * takes a write fault on a MAP_NOSYNC memory area the flag will 5577 * be set again. 5578 * 5579 * We set valid bits inclusive of any overlap, but we can only 5580 * clear dirty bits for DEV_BSIZE chunks that are fully within 5581 * the range. 5582 */ 5583 oldvalid = m->valid; 5584 pagebits = vm_page_bits(base, size); 5585 if (vm_page_xbusied(m)) 5586 m->valid |= pagebits; 5587 else 5588 vm_page_bits_set(m, &m->valid, pagebits); 5589 #if 0 /* NOT YET */ 5590 if ((frag = base & (DEV_BSIZE - 1)) != 0) { 5591 frag = DEV_BSIZE - frag; 5592 base += frag; 5593 size -= frag; 5594 if (size < 0) 5595 size = 0; 5596 } 5597 pagebits = vm_page_bits(base, size & (DEV_BSIZE - 1)); 5598 #endif 5599 if (base == 0 && size == PAGE_SIZE) { 5600 /* 5601 * The page can only be modified within the pmap if it is 5602 * mapped, and it can only be mapped if it was previously 5603 * fully valid. 5604 */ 5605 if (oldvalid == VM_PAGE_BITS_ALL) 5606 /* 5607 * Perform the pmap_clear_modify() first. Otherwise, 5608 * a concurrent pmap operation, such as 5609 * pmap_protect(), could clear a modification in the 5610 * pmap and set the dirty field on the page before 5611 * pmap_clear_modify() had begun and after the dirty 5612 * field was cleared here. 5613 */ 5614 pmap_clear_modify(m); 5615 m->dirty = 0; 5616 vm_page_aflag_clear(m, PGA_NOSYNC); 5617 } else if (oldvalid != VM_PAGE_BITS_ALL && vm_page_xbusied(m)) 5618 m->dirty &= ~pagebits; 5619 else 5620 vm_page_clear_dirty_mask(m, pagebits); 5621 } 5622 5623 void 5624 vm_page_clear_dirty(vm_page_t m, int base, int size) 5625 { 5626 5627 vm_page_clear_dirty_mask(m, vm_page_bits(base, size)); 5628 } 5629 5630 /* 5631 * vm_page_set_invalid: 5632 * 5633 * Invalidates DEV_BSIZE'd chunks within a page. Both the 5634 * valid and dirty bits for the effected areas are cleared. 5635 */ 5636 void 5637 vm_page_set_invalid(vm_page_t m, int base, int size) 5638 { 5639 vm_page_bits_t bits; 5640 vm_object_t object; 5641 5642 /* 5643 * The object lock is required so that pages can't be mapped 5644 * read-only while we're in the process of invalidating them. 5645 */ 5646 object = m->object; 5647 VM_OBJECT_ASSERT_WLOCKED(object); 5648 vm_page_assert_busied(m); 5649 5650 if (object->type == OBJT_VNODE && base == 0 && IDX_TO_OFF(m->pindex) + 5651 size >= object->un_pager.vnp.vnp_size) 5652 bits = VM_PAGE_BITS_ALL; 5653 else 5654 bits = vm_page_bits(base, size); 5655 if (object->ref_count != 0 && vm_page_all_valid(m) && bits != 0) 5656 pmap_remove_all(m); 5657 KASSERT((bits == 0 && vm_page_all_valid(m)) || 5658 !pmap_page_is_mapped(m), 5659 ("vm_page_set_invalid: page %p is mapped", m)); 5660 if (vm_page_xbusied(m)) { 5661 m->valid &= ~bits; 5662 m->dirty &= ~bits; 5663 } else { 5664 vm_page_bits_clear(m, &m->valid, bits); 5665 vm_page_bits_clear(m, &m->dirty, bits); 5666 } 5667 } 5668 5669 /* 5670 * vm_page_invalid: 5671 * 5672 * Invalidates the entire page. The page must be busy, unmapped, and 5673 * the enclosing object must be locked. The object locks protects 5674 * against concurrent read-only pmap enter which is done without 5675 * busy. 5676 */ 5677 void 5678 vm_page_invalid(vm_page_t m) 5679 { 5680 5681 vm_page_assert_busied(m); 5682 VM_OBJECT_ASSERT_WLOCKED(m->object); 5683 MPASS(!pmap_page_is_mapped(m)); 5684 5685 if (vm_page_xbusied(m)) 5686 m->valid = 0; 5687 else 5688 vm_page_bits_clear(m, &m->valid, VM_PAGE_BITS_ALL); 5689 } 5690 5691 /* 5692 * vm_page_zero_invalid() 5693 * 5694 * The kernel assumes that the invalid portions of a page contain 5695 * garbage, but such pages can be mapped into memory by user code. 5696 * When this occurs, we must zero out the non-valid portions of the 5697 * page so user code sees what it expects. 5698 * 5699 * Pages are most often semi-valid when the end of a file is mapped 5700 * into memory and the file's size is not page aligned. 5701 */ 5702 void 5703 vm_page_zero_invalid(vm_page_t m, boolean_t setvalid) 5704 { 5705 int b; 5706 int i; 5707 5708 /* 5709 * Scan the valid bits looking for invalid sections that 5710 * must be zeroed. Invalid sub-DEV_BSIZE'd areas ( where the 5711 * valid bit may be set ) have already been zeroed by 5712 * vm_page_set_validclean(). 5713 */ 5714 for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) { 5715 if (i == (PAGE_SIZE / DEV_BSIZE) || 5716 (m->valid & ((vm_page_bits_t)1 << i))) { 5717 if (i > b) { 5718 pmap_zero_page_area(m, 5719 b << DEV_BSHIFT, (i - b) << DEV_BSHIFT); 5720 } 5721 b = i + 1; 5722 } 5723 } 5724 5725 /* 5726 * setvalid is TRUE when we can safely set the zero'd areas 5727 * as being valid. We can do this if there are no cache consistency 5728 * issues. e.g. it is ok to do with UFS, but not ok to do with NFS. 5729 */ 5730 if (setvalid) 5731 vm_page_valid(m); 5732 } 5733 5734 /* 5735 * vm_page_is_valid: 5736 * 5737 * Is (partial) page valid? Note that the case where size == 0 5738 * will return FALSE in the degenerate case where the page is 5739 * entirely invalid, and TRUE otherwise. 5740 * 5741 * Some callers envoke this routine without the busy lock held and 5742 * handle races via higher level locks. Typical callers should 5743 * hold a busy lock to prevent invalidation. 5744 */ 5745 int 5746 vm_page_is_valid(vm_page_t m, int base, int size) 5747 { 5748 vm_page_bits_t bits; 5749 5750 bits = vm_page_bits(base, size); 5751 return (vm_page_any_valid(m) && (m->valid & bits) == bits); 5752 } 5753 5754 /* 5755 * Returns true if all of the specified predicates are true for the entire 5756 * (super)page and false otherwise. 5757 */ 5758 bool 5759 vm_page_ps_test(vm_page_t m, int psind, int flags, vm_page_t skip_m) 5760 { 5761 vm_object_t object; 5762 int i, npages; 5763 5764 object = m->object; 5765 if (skip_m != NULL && skip_m->object != object) 5766 return (false); 5767 VM_OBJECT_ASSERT_LOCKED(object); 5768 KASSERT(psind <= m->psind, 5769 ("psind %d > psind %d of m %p", psind, m->psind, m)); 5770 npages = atop(pagesizes[psind]); 5771 5772 /* 5773 * The physically contiguous pages that make up a superpage, i.e., a 5774 * page with a page size index ("psind") greater than zero, will 5775 * occupy adjacent entries in vm_page_array[]. 5776 */ 5777 for (i = 0; i < npages; i++) { 5778 /* Always test object consistency, including "skip_m". */ 5779 if (m[i].object != object) 5780 return (false); 5781 if (&m[i] == skip_m) 5782 continue; 5783 if ((flags & PS_NONE_BUSY) != 0 && vm_page_busied(&m[i])) 5784 return (false); 5785 if ((flags & PS_ALL_DIRTY) != 0) { 5786 /* 5787 * Calling vm_page_test_dirty() or pmap_is_modified() 5788 * might stop this case from spuriously returning 5789 * "false". However, that would require a write lock 5790 * on the object containing "m[i]". 5791 */ 5792 if (m[i].dirty != VM_PAGE_BITS_ALL) 5793 return (false); 5794 } 5795 if ((flags & PS_ALL_VALID) != 0 && 5796 m[i].valid != VM_PAGE_BITS_ALL) 5797 return (false); 5798 } 5799 return (true); 5800 } 5801 5802 /* 5803 * Set the page's dirty bits if the page is modified. 5804 */ 5805 void 5806 vm_page_test_dirty(vm_page_t m) 5807 { 5808 5809 vm_page_assert_busied(m); 5810 if (m->dirty != VM_PAGE_BITS_ALL && pmap_is_modified(m)) 5811 vm_page_dirty(m); 5812 } 5813 5814 void 5815 vm_page_valid(vm_page_t m) 5816 { 5817 5818 vm_page_assert_busied(m); 5819 if (vm_page_xbusied(m)) 5820 m->valid = VM_PAGE_BITS_ALL; 5821 else 5822 vm_page_bits_set(m, &m->valid, VM_PAGE_BITS_ALL); 5823 } 5824 5825 void 5826 vm_page_lock_KBI(vm_page_t m, const char *file, int line) 5827 { 5828 5829 mtx_lock_flags_(vm_page_lockptr(m), 0, file, line); 5830 } 5831 5832 void 5833 vm_page_unlock_KBI(vm_page_t m, const char *file, int line) 5834 { 5835 5836 mtx_unlock_flags_(vm_page_lockptr(m), 0, file, line); 5837 } 5838 5839 int 5840 vm_page_trylock_KBI(vm_page_t m, const char *file, int line) 5841 { 5842 5843 return (mtx_trylock_flags_(vm_page_lockptr(m), 0, file, line)); 5844 } 5845 5846 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT) 5847 void 5848 vm_page_assert_locked_KBI(vm_page_t m, const char *file, int line) 5849 { 5850 5851 vm_page_lock_assert_KBI(m, MA_OWNED, file, line); 5852 } 5853 5854 void 5855 vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line) 5856 { 5857 5858 mtx_assert_(vm_page_lockptr(m), a, file, line); 5859 } 5860 #endif 5861 5862 #ifdef INVARIANTS 5863 void 5864 vm_page_object_busy_assert(vm_page_t m) 5865 { 5866 5867 /* 5868 * Certain of the page's fields may only be modified by the 5869 * holder of a page or object busy. 5870 */ 5871 if (m->object != NULL && !vm_page_busied(m)) 5872 VM_OBJECT_ASSERT_BUSY(m->object); 5873 } 5874 5875 void 5876 vm_page_assert_pga_writeable(vm_page_t m, uint16_t bits) 5877 { 5878 5879 if ((bits & PGA_WRITEABLE) == 0) 5880 return; 5881 5882 /* 5883 * The PGA_WRITEABLE flag can only be set if the page is 5884 * managed, is exclusively busied or the object is locked. 5885 * Currently, this flag is only set by pmap_enter(). 5886 */ 5887 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 5888 ("PGA_WRITEABLE on unmanaged page")); 5889 if (!vm_page_xbusied(m)) 5890 VM_OBJECT_ASSERT_BUSY(m->object); 5891 } 5892 #endif 5893 5894 #include "opt_ddb.h" 5895 #ifdef DDB 5896 #include <sys/kernel.h> 5897 5898 #include <ddb/ddb.h> 5899 5900 DB_SHOW_COMMAND_FLAGS(page, vm_page_print_page_info, DB_CMD_MEMSAFE) 5901 { 5902 5903 db_printf("vm_cnt.v_free_count: %d\n", vm_free_count()); 5904 db_printf("vm_cnt.v_inactive_count: %d\n", vm_inactive_count()); 5905 db_printf("vm_cnt.v_active_count: %d\n", vm_active_count()); 5906 db_printf("vm_cnt.v_laundry_count: %d\n", vm_laundry_count()); 5907 db_printf("vm_cnt.v_wire_count: %d\n", vm_wire_count()); 5908 db_printf("vm_cnt.v_free_reserved: %d\n", vm_cnt.v_free_reserved); 5909 db_printf("vm_cnt.v_free_min: %d\n", vm_cnt.v_free_min); 5910 db_printf("vm_cnt.v_free_target: %d\n", vm_cnt.v_free_target); 5911 db_printf("vm_cnt.v_inactive_target: %d\n", vm_cnt.v_inactive_target); 5912 } 5913 5914 DB_SHOW_COMMAND_FLAGS(pageq, vm_page_print_pageq_info, DB_CMD_MEMSAFE) 5915 { 5916 int dom; 5917 5918 db_printf("pq_free %d\n", vm_free_count()); 5919 for (dom = 0; dom < vm_ndomains; dom++) { 5920 db_printf( 5921 "dom %d page_cnt %d free %d pq_act %d pq_inact %d pq_laund %d pq_unsw %d\n", 5922 dom, 5923 vm_dom[dom].vmd_page_count, 5924 vm_dom[dom].vmd_free_count, 5925 vm_dom[dom].vmd_pagequeues[PQ_ACTIVE].pq_cnt, 5926 vm_dom[dom].vmd_pagequeues[PQ_INACTIVE].pq_cnt, 5927 vm_dom[dom].vmd_pagequeues[PQ_LAUNDRY].pq_cnt, 5928 vm_dom[dom].vmd_pagequeues[PQ_UNSWAPPABLE].pq_cnt); 5929 } 5930 } 5931 5932 DB_SHOW_COMMAND(pginfo, vm_page_print_pginfo) 5933 { 5934 vm_page_t m; 5935 boolean_t phys, virt; 5936 5937 if (!have_addr) { 5938 db_printf("show pginfo addr\n"); 5939 return; 5940 } 5941 5942 phys = strchr(modif, 'p') != NULL; 5943 virt = strchr(modif, 'v') != NULL; 5944 if (virt) 5945 m = PHYS_TO_VM_PAGE(pmap_kextract(addr)); 5946 else if (phys) 5947 m = PHYS_TO_VM_PAGE(addr); 5948 else 5949 m = (vm_page_t)addr; 5950 db_printf( 5951 "page %p obj %p pidx 0x%jx phys 0x%jx q %d ref 0x%x\n" 5952 " af 0x%x of 0x%x f 0x%x act %d busy %x valid 0x%x dirty 0x%x\n", 5953 m, m->object, (uintmax_t)m->pindex, (uintmax_t)m->phys_addr, 5954 m->a.queue, m->ref_count, m->a.flags, m->oflags, 5955 m->flags, m->a.act_count, m->busy_lock, m->valid, m->dirty); 5956 } 5957 #endif /* DDB */ 5958