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 * Do the work to remove a page from its object. The caller is responsible for 1643 * updating the page's fields to reflect this removal. 1644 */ 1645 static void 1646 vm_page_object_remove(vm_page_t m) 1647 { 1648 vm_object_t object; 1649 vm_page_t mrem __diagused; 1650 1651 vm_page_assert_xbusied(m); 1652 object = m->object; 1653 VM_OBJECT_ASSERT_WLOCKED(object); 1654 KASSERT((m->ref_count & VPRC_OBJREF) != 0, 1655 ("page %p is missing its object ref", m)); 1656 1657 /* Deferred free of swap space. */ 1658 if ((m->a.flags & PGA_SWAP_FREE) != 0) 1659 vm_pager_page_unswapped(m); 1660 1661 vm_pager_page_removed(object, m); 1662 1663 m->object = NULL; 1664 mrem = vm_radix_remove(&object->rtree, m->pindex); 1665 KASSERT(mrem == m, ("removed page %p, expected page %p", mrem, m)); 1666 1667 /* 1668 * Now remove from the object's list of backed pages. 1669 */ 1670 TAILQ_REMOVE(&object->memq, m, listq); 1671 1672 /* 1673 * And show that the object has one fewer resident page. 1674 */ 1675 object->resident_page_count--; 1676 1677 /* 1678 * The vnode may now be recycled. 1679 */ 1680 if (object->resident_page_count == 0 && object->type == OBJT_VNODE) 1681 vdrop(object->handle); 1682 } 1683 1684 /* 1685 * vm_page_remove: 1686 * 1687 * Removes the specified page from its containing object, but does not 1688 * invalidate any backing storage. Returns true if the object's reference 1689 * was the last reference to the page, and false otherwise. 1690 * 1691 * The object must be locked and the page must be exclusively busied. 1692 * The exclusive busy will be released on return. If this is not the 1693 * final ref and the caller does not hold a wire reference it may not 1694 * continue to access the page. 1695 */ 1696 bool 1697 vm_page_remove(vm_page_t m) 1698 { 1699 bool dropped; 1700 1701 dropped = vm_page_remove_xbusy(m); 1702 vm_page_xunbusy(m); 1703 1704 return (dropped); 1705 } 1706 1707 /* 1708 * vm_page_remove_xbusy 1709 * 1710 * Removes the page but leaves the xbusy held. Returns true if this 1711 * removed the final ref and false otherwise. 1712 */ 1713 bool 1714 vm_page_remove_xbusy(vm_page_t m) 1715 { 1716 1717 vm_page_object_remove(m); 1718 return (vm_page_drop(m, VPRC_OBJREF) == VPRC_OBJREF); 1719 } 1720 1721 /* 1722 * vm_page_lookup: 1723 * 1724 * Returns the page associated with the object/offset 1725 * pair specified; if none is found, NULL is returned. 1726 * 1727 * The object must be locked. 1728 */ 1729 vm_page_t 1730 vm_page_lookup(vm_object_t object, vm_pindex_t pindex) 1731 { 1732 1733 VM_OBJECT_ASSERT_LOCKED(object); 1734 return (vm_radix_lookup(&object->rtree, pindex)); 1735 } 1736 1737 /* 1738 * vm_page_iter_init: 1739 * 1740 * Initialize iterator for vm pages. 1741 */ 1742 void 1743 vm_page_iter_init(struct pctrie_iter *pages, vm_object_t object) 1744 { 1745 1746 vm_radix_iter_init(pages, &object->rtree); 1747 } 1748 1749 /* 1750 * vm_page_iter_init: 1751 * 1752 * Initialize iterator for vm pages. 1753 */ 1754 void 1755 vm_page_iter_limit_init(struct pctrie_iter *pages, vm_object_t object, 1756 vm_pindex_t limit) 1757 { 1758 1759 vm_radix_iter_limit_init(pages, &object->rtree, limit); 1760 } 1761 1762 /* 1763 * vm_page_iter_lookup: 1764 * 1765 * Returns the page associated with the object/offset pair specified, and 1766 * stores the path to its position; if none is found, NULL is returned. 1767 * 1768 * The iter pctrie must be locked. 1769 */ 1770 vm_page_t 1771 vm_page_iter_lookup(struct pctrie_iter *pages, vm_pindex_t pindex) 1772 { 1773 1774 return (vm_radix_iter_lookup(pages, pindex)); 1775 } 1776 1777 /* 1778 * vm_page_lookup_unlocked: 1779 * 1780 * Returns the page associated with the object/offset pair specified; 1781 * if none is found, NULL is returned. The page may be no longer be 1782 * present in the object at the time that this function returns. Only 1783 * useful for opportunistic checks such as inmem(). 1784 */ 1785 vm_page_t 1786 vm_page_lookup_unlocked(vm_object_t object, vm_pindex_t pindex) 1787 { 1788 1789 return (vm_radix_lookup_unlocked(&object->rtree, pindex)); 1790 } 1791 1792 /* 1793 * vm_page_relookup: 1794 * 1795 * Returns a page that must already have been busied by 1796 * the caller. Used for bogus page replacement. 1797 */ 1798 vm_page_t 1799 vm_page_relookup(vm_object_t object, vm_pindex_t pindex) 1800 { 1801 vm_page_t m; 1802 1803 m = vm_page_lookup_unlocked(object, pindex); 1804 KASSERT(m != NULL && (vm_page_busied(m) || vm_page_wired(m)) && 1805 m->object == object && m->pindex == pindex, 1806 ("vm_page_relookup: Invalid page %p", m)); 1807 return (m); 1808 } 1809 1810 /* 1811 * This should only be used by lockless functions for releasing transient 1812 * incorrect acquires. The page may have been freed after we acquired a 1813 * busy lock. In this case busy_lock == VPB_FREED and we have nothing 1814 * further to do. 1815 */ 1816 static void 1817 vm_page_busy_release(vm_page_t m) 1818 { 1819 u_int x; 1820 1821 x = vm_page_busy_fetch(m); 1822 for (;;) { 1823 if (x == VPB_FREED) 1824 break; 1825 if ((x & VPB_BIT_SHARED) != 0 && VPB_SHARERS(x) > 1) { 1826 if (atomic_fcmpset_int(&m->busy_lock, &x, 1827 x - VPB_ONE_SHARER)) 1828 break; 1829 continue; 1830 } 1831 KASSERT((x & VPB_BIT_SHARED) != 0 || 1832 (x & ~VPB_BIT_WAITERS) == VPB_CURTHREAD_EXCLUSIVE, 1833 ("vm_page_busy_release: %p xbusy not owned.", m)); 1834 if (!atomic_fcmpset_rel_int(&m->busy_lock, &x, VPB_UNBUSIED)) 1835 continue; 1836 if ((x & VPB_BIT_WAITERS) != 0) 1837 wakeup(m); 1838 break; 1839 } 1840 } 1841 1842 /* 1843 * vm_page_find_least: 1844 * 1845 * Returns the page associated with the object with least pindex 1846 * greater than or equal to the parameter pindex, or NULL. 1847 * 1848 * The object must be locked. 1849 */ 1850 vm_page_t 1851 vm_page_find_least(vm_object_t object, vm_pindex_t pindex) 1852 { 1853 vm_page_t m; 1854 1855 VM_OBJECT_ASSERT_LOCKED(object); 1856 if ((m = TAILQ_FIRST(&object->memq)) != NULL && m->pindex < pindex) 1857 m = vm_radix_lookup_ge(&object->rtree, pindex); 1858 return (m); 1859 } 1860 1861 /* 1862 * vm_page_iter_lookup_ge: 1863 * 1864 * Returns the page associated with the object with least pindex 1865 * greater than or equal to the parameter pindex, or NULL. Initializes the 1866 * iterator to point to that page. 1867 * 1868 * The iter pctrie must be locked. 1869 */ 1870 vm_page_t 1871 vm_page_iter_lookup_ge(struct pctrie_iter *pages, vm_pindex_t pindex) 1872 { 1873 1874 return (vm_radix_iter_lookup_ge(pages, pindex)); 1875 } 1876 1877 /* 1878 * Returns the given page's successor (by pindex) within the object if it is 1879 * resident; if none is found, NULL is returned. 1880 * 1881 * The object must be locked. 1882 */ 1883 vm_page_t 1884 vm_page_next(vm_page_t m) 1885 { 1886 vm_page_t next; 1887 1888 VM_OBJECT_ASSERT_LOCKED(m->object); 1889 if ((next = TAILQ_NEXT(m, listq)) != NULL) { 1890 MPASS(next->object == m->object); 1891 if (next->pindex != m->pindex + 1) 1892 next = NULL; 1893 } 1894 return (next); 1895 } 1896 1897 /* 1898 * Returns the given page's predecessor (by pindex) within the object if it is 1899 * resident; if none is found, NULL is returned. 1900 * 1901 * The object must be locked. 1902 */ 1903 vm_page_t 1904 vm_page_prev(vm_page_t m) 1905 { 1906 vm_page_t prev; 1907 1908 VM_OBJECT_ASSERT_LOCKED(m->object); 1909 if ((prev = TAILQ_PREV(m, pglist, listq)) != NULL) { 1910 MPASS(prev->object == m->object); 1911 if (prev->pindex != m->pindex - 1) 1912 prev = NULL; 1913 } 1914 return (prev); 1915 } 1916 1917 /* 1918 * Uses the page mnew as a replacement for an existing page at index 1919 * pindex which must be already present in the object. 1920 * 1921 * Both pages must be exclusively busied on enter. The old page is 1922 * unbusied on exit. 1923 * 1924 * A return value of true means mold is now free. If this is not the 1925 * final ref and the caller does not hold a wire reference it may not 1926 * continue to access the page. 1927 */ 1928 static bool 1929 vm_page_replace_hold(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex, 1930 vm_page_t mold) 1931 { 1932 vm_page_t mret __diagused; 1933 bool dropped; 1934 1935 VM_OBJECT_ASSERT_WLOCKED(object); 1936 vm_page_assert_xbusied(mold); 1937 KASSERT(mnew->object == NULL && (mnew->ref_count & VPRC_OBJREF) == 0, 1938 ("vm_page_replace: page %p already in object", mnew)); 1939 1940 /* 1941 * This function mostly follows vm_page_insert() and 1942 * vm_page_remove() without the radix, object count and vnode 1943 * dance. Double check such functions for more comments. 1944 */ 1945 1946 mnew->object = object; 1947 mnew->pindex = pindex; 1948 atomic_set_int(&mnew->ref_count, VPRC_OBJREF); 1949 mret = vm_radix_replace(&object->rtree, mnew); 1950 KASSERT(mret == mold, 1951 ("invalid page replacement, mold=%p, mret=%p", mold, mret)); 1952 KASSERT((mold->oflags & VPO_UNMANAGED) == 1953 (mnew->oflags & VPO_UNMANAGED), 1954 ("vm_page_replace: mismatched VPO_UNMANAGED")); 1955 1956 /* Keep the resident page list in sorted order. */ 1957 TAILQ_INSERT_AFTER(&object->memq, mold, mnew, listq); 1958 TAILQ_REMOVE(&object->memq, mold, listq); 1959 mold->object = NULL; 1960 1961 /* 1962 * The object's resident_page_count does not change because we have 1963 * swapped one page for another, but the generation count should 1964 * change if the page is dirty. 1965 */ 1966 if (pmap_page_is_write_mapped(mnew)) 1967 vm_object_set_writeable_dirty(object); 1968 dropped = vm_page_drop(mold, VPRC_OBJREF) == VPRC_OBJREF; 1969 vm_page_xunbusy(mold); 1970 1971 return (dropped); 1972 } 1973 1974 void 1975 vm_page_replace(vm_page_t mnew, vm_object_t object, vm_pindex_t pindex, 1976 vm_page_t mold) 1977 { 1978 1979 vm_page_assert_xbusied(mnew); 1980 1981 if (vm_page_replace_hold(mnew, object, pindex, mold)) 1982 vm_page_free(mold); 1983 } 1984 1985 /* 1986 * vm_page_rename: 1987 * 1988 * Move the given memory entry from its 1989 * current object to the specified target object/offset. 1990 * 1991 * Note: swap associated with the page must be invalidated by the move. We 1992 * have to do this for several reasons: (1) we aren't freeing the 1993 * page, (2) we are dirtying the page, (3) the VM system is probably 1994 * moving the page from object A to B, and will then later move 1995 * the backing store from A to B and we can't have a conflict. 1996 * 1997 * Note: we *always* dirty the page. It is necessary both for the 1998 * fact that we moved it, and because we may be invalidating 1999 * swap. 2000 * 2001 * The objects must be locked. 2002 */ 2003 int 2004 vm_page_rename(vm_page_t m, vm_object_t new_object, vm_pindex_t new_pindex) 2005 { 2006 vm_page_t mpred; 2007 vm_pindex_t opidx; 2008 2009 VM_OBJECT_ASSERT_WLOCKED(new_object); 2010 2011 KASSERT(m->ref_count != 0, ("vm_page_rename: page %p has no refs", m)); 2012 2013 /* 2014 * Create a custom version of vm_page_insert() which does not depend 2015 * by m_prev and can cheat on the implementation aspects of the 2016 * function. 2017 */ 2018 opidx = m->pindex; 2019 m->pindex = new_pindex; 2020 if (vm_radix_insert_lookup_lt(&new_object->rtree, m, &mpred) != 0) { 2021 m->pindex = opidx; 2022 return (1); 2023 } 2024 2025 /* 2026 * The operation cannot fail anymore. The removal must happen before 2027 * the listq iterator is tainted. 2028 */ 2029 m->pindex = opidx; 2030 vm_page_object_remove(m); 2031 2032 /* Return back to the new pindex to complete vm_page_insert(). */ 2033 m->pindex = new_pindex; 2034 m->object = new_object; 2035 2036 vm_page_insert_radixdone(m, new_object, mpred); 2037 vm_page_dirty(m); 2038 vm_pager_page_inserted(new_object, m); 2039 return (0); 2040 } 2041 2042 /* 2043 * vm_page_mpred: 2044 * 2045 * Return the greatest page of the object with index <= pindex, 2046 * or NULL, if there is none. Assumes object lock is held. 2047 */ 2048 vm_page_t 2049 vm_page_mpred(vm_object_t object, vm_pindex_t pindex) 2050 { 2051 return (vm_radix_lookup_le(&object->rtree, pindex)); 2052 } 2053 2054 /* 2055 * vm_page_alloc: 2056 * 2057 * Allocate and return a page that is associated with the specified 2058 * object and offset pair. By default, this page is exclusive busied. 2059 * 2060 * The caller must always specify an allocation class. 2061 * 2062 * allocation classes: 2063 * VM_ALLOC_NORMAL normal process request 2064 * VM_ALLOC_SYSTEM system *really* needs a page 2065 * VM_ALLOC_INTERRUPT interrupt time request 2066 * 2067 * optional allocation flags: 2068 * VM_ALLOC_COUNT(number) the number of additional pages that the caller 2069 * intends to allocate 2070 * VM_ALLOC_NOBUSY do not exclusive busy the page 2071 * VM_ALLOC_NODUMP do not include the page in a kernel core dump 2072 * VM_ALLOC_SBUSY shared busy the allocated page 2073 * VM_ALLOC_WIRED wire the allocated page 2074 * VM_ALLOC_ZERO prefer a zeroed page 2075 */ 2076 vm_page_t 2077 vm_page_alloc(vm_object_t object, vm_pindex_t pindex, int req) 2078 { 2079 2080 return (vm_page_alloc_after(object, pindex, req, 2081 vm_page_mpred(object, pindex))); 2082 } 2083 2084 /* 2085 * Allocate a page in the specified object with the given page index. To 2086 * optimize insertion of the page into the object, the caller must also specify 2087 * the resident page in the object with largest index smaller than the given 2088 * page index, or NULL if no such page exists. 2089 */ 2090 static vm_page_t 2091 vm_page_alloc_after(vm_object_t object, vm_pindex_t pindex, 2092 int req, vm_page_t mpred) 2093 { 2094 struct vm_domainset_iter di; 2095 vm_page_t m; 2096 int domain; 2097 2098 vm_domainset_iter_page_init(&di, object, pindex, &domain, &req); 2099 do { 2100 m = vm_page_alloc_domain_after(object, pindex, domain, req, 2101 mpred); 2102 if (m != NULL) 2103 break; 2104 } while (vm_domainset_iter_page(&di, object, &domain) == 0); 2105 2106 return (m); 2107 } 2108 2109 /* 2110 * Returns true if the number of free pages exceeds the minimum 2111 * for the request class and false otherwise. 2112 */ 2113 static int 2114 _vm_domain_allocate(struct vm_domain *vmd, int req_class, int npages) 2115 { 2116 u_int limit, old, new; 2117 2118 if (req_class == VM_ALLOC_INTERRUPT) 2119 limit = 0; 2120 else if (req_class == VM_ALLOC_SYSTEM) 2121 limit = vmd->vmd_interrupt_free_min; 2122 else 2123 limit = vmd->vmd_free_reserved; 2124 2125 /* 2126 * Attempt to reserve the pages. Fail if we're below the limit. 2127 */ 2128 limit += npages; 2129 old = atomic_load_int(&vmd->vmd_free_count); 2130 do { 2131 if (old < limit) 2132 return (0); 2133 new = old - npages; 2134 } while (atomic_fcmpset_int(&vmd->vmd_free_count, &old, new) == 0); 2135 2136 /* Wake the page daemon if we've crossed the threshold. */ 2137 if (vm_paging_needed(vmd, new) && !vm_paging_needed(vmd, old)) 2138 pagedaemon_wakeup(vmd->vmd_domain); 2139 2140 /* Only update bitsets on transitions. */ 2141 if ((old >= vmd->vmd_free_min && new < vmd->vmd_free_min) || 2142 (old >= vmd->vmd_free_severe && new < vmd->vmd_free_severe)) 2143 vm_domain_set(vmd); 2144 2145 return (1); 2146 } 2147 2148 int 2149 vm_domain_allocate(struct vm_domain *vmd, int req, int npages) 2150 { 2151 int req_class; 2152 2153 /* 2154 * The page daemon is allowed to dig deeper into the free page list. 2155 */ 2156 req_class = req & VM_ALLOC_CLASS_MASK; 2157 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 2158 req_class = VM_ALLOC_SYSTEM; 2159 return (_vm_domain_allocate(vmd, req_class, npages)); 2160 } 2161 2162 vm_page_t 2163 vm_page_alloc_domain_after(vm_object_t object, vm_pindex_t pindex, int domain, 2164 int req, vm_page_t mpred) 2165 { 2166 struct vm_domain *vmd; 2167 vm_page_t m; 2168 int flags; 2169 2170 #define VPA_FLAGS (VM_ALLOC_CLASS_MASK | VM_ALLOC_WAITFAIL | \ 2171 VM_ALLOC_NOWAIT | VM_ALLOC_NOBUSY | \ 2172 VM_ALLOC_SBUSY | VM_ALLOC_WIRED | \ 2173 VM_ALLOC_NODUMP | VM_ALLOC_ZERO | \ 2174 VM_ALLOC_NOFREE | VM_ALLOC_COUNT_MASK) 2175 KASSERT((req & ~VPA_FLAGS) == 0, 2176 ("invalid request %#x", req)); 2177 KASSERT(((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 2178 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 2179 ("invalid request %#x", req)); 2180 KASSERT(mpred == NULL || mpred->pindex < pindex, 2181 ("mpred %p doesn't precede pindex 0x%jx", mpred, 2182 (uintmax_t)pindex)); 2183 VM_OBJECT_ASSERT_WLOCKED(object); 2184 2185 flags = 0; 2186 m = NULL; 2187 if (!vm_pager_can_alloc_page(object, pindex)) 2188 return (NULL); 2189 again: 2190 if (__predict_false((req & VM_ALLOC_NOFREE) != 0)) { 2191 m = vm_page_alloc_nofree_domain(domain, req); 2192 if (m != NULL) 2193 goto found; 2194 } 2195 #if VM_NRESERVLEVEL > 0 2196 /* 2197 * Can we allocate the page from a reservation? 2198 */ 2199 if (vm_object_reserv(object) && 2200 (m = vm_reserv_alloc_page(object, pindex, domain, req, mpred)) != 2201 NULL) { 2202 goto found; 2203 } 2204 #endif 2205 vmd = VM_DOMAIN(domain); 2206 if (vmd->vmd_pgcache[VM_FREEPOOL_DEFAULT].zone != NULL) { 2207 m = uma_zalloc(vmd->vmd_pgcache[VM_FREEPOOL_DEFAULT].zone, 2208 M_NOWAIT | M_NOVM); 2209 if (m != NULL) { 2210 flags |= PG_PCPU_CACHE; 2211 goto found; 2212 } 2213 } 2214 if (vm_domain_allocate(vmd, req, 1)) { 2215 /* 2216 * If not, allocate it from the free page queues. 2217 */ 2218 vm_domain_free_lock(vmd); 2219 m = vm_phys_alloc_pages(domain, VM_FREEPOOL_DEFAULT, 0); 2220 vm_domain_free_unlock(vmd); 2221 if (m == NULL) { 2222 vm_domain_freecnt_inc(vmd, 1); 2223 #if VM_NRESERVLEVEL > 0 2224 if (vm_reserv_reclaim_inactive(domain)) 2225 goto again; 2226 #endif 2227 } 2228 } 2229 if (m == NULL) { 2230 /* 2231 * Not allocatable, give up. 2232 */ 2233 if (vm_domain_alloc_fail(vmd, object, req)) 2234 goto again; 2235 return (NULL); 2236 } 2237 2238 /* 2239 * At this point we had better have found a good page. 2240 */ 2241 found: 2242 vm_page_dequeue(m); 2243 vm_page_alloc_check(m); 2244 2245 /* 2246 * Initialize the page. Only the PG_ZERO flag is inherited. 2247 */ 2248 flags |= m->flags & PG_ZERO; 2249 if ((req & VM_ALLOC_NODUMP) != 0) 2250 flags |= PG_NODUMP; 2251 if ((req & VM_ALLOC_NOFREE) != 0) 2252 flags |= PG_NOFREE; 2253 m->flags = flags; 2254 m->a.flags = 0; 2255 m->oflags = (object->flags & OBJ_UNMANAGED) != 0 ? VPO_UNMANAGED : 0; 2256 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0) 2257 m->busy_lock = VPB_CURTHREAD_EXCLUSIVE; 2258 else if ((req & VM_ALLOC_SBUSY) != 0) 2259 m->busy_lock = VPB_SHARERS_WORD(1); 2260 else 2261 m->busy_lock = VPB_UNBUSIED; 2262 if (req & VM_ALLOC_WIRED) { 2263 vm_wire_add(1); 2264 m->ref_count = 1; 2265 } 2266 m->a.act_count = 0; 2267 2268 if (vm_page_insert_after(m, object, pindex, mpred)) { 2269 if (req & VM_ALLOC_WIRED) { 2270 vm_wire_sub(1); 2271 m->ref_count = 0; 2272 } 2273 KASSERT(m->object == NULL, ("page %p has object", m)); 2274 m->oflags = VPO_UNMANAGED; 2275 m->busy_lock = VPB_UNBUSIED; 2276 /* Don't change PG_ZERO. */ 2277 vm_page_free_toq(m); 2278 if (req & VM_ALLOC_WAITFAIL) { 2279 VM_OBJECT_WUNLOCK(object); 2280 vm_radix_wait(); 2281 VM_OBJECT_WLOCK(object); 2282 } 2283 return (NULL); 2284 } 2285 2286 /* Ignore device objects; the pager sets "memattr" for them. */ 2287 if (object->memattr != VM_MEMATTR_DEFAULT && 2288 (object->flags & OBJ_FICTITIOUS) == 0) 2289 pmap_page_set_memattr(m, object->memattr); 2290 2291 return (m); 2292 } 2293 2294 /* 2295 * vm_page_alloc_contig: 2296 * 2297 * Allocate a contiguous set of physical pages of the given size "npages" 2298 * from the free lists. All of the physical pages must be at or above 2299 * the given physical address "low" and below the given physical address 2300 * "high". The given value "alignment" determines the alignment of the 2301 * first physical page in the set. If the given value "boundary" is 2302 * non-zero, then the set of physical pages cannot cross any physical 2303 * address boundary that is a multiple of that value. Both "alignment" 2304 * and "boundary" must be a power of two. 2305 * 2306 * If the specified memory attribute, "memattr", is VM_MEMATTR_DEFAULT, 2307 * then the memory attribute setting for the physical pages is configured 2308 * to the object's memory attribute setting. Otherwise, the memory 2309 * attribute setting for the physical pages is configured to "memattr", 2310 * overriding the object's memory attribute setting. However, if the 2311 * object's memory attribute setting is not VM_MEMATTR_DEFAULT, then the 2312 * memory attribute setting for the physical pages cannot be configured 2313 * to VM_MEMATTR_DEFAULT. 2314 * 2315 * The specified object may not contain fictitious pages. 2316 * 2317 * The caller must always specify an allocation class. 2318 * 2319 * allocation classes: 2320 * VM_ALLOC_NORMAL normal process request 2321 * VM_ALLOC_SYSTEM system *really* needs a page 2322 * VM_ALLOC_INTERRUPT interrupt time request 2323 * 2324 * optional allocation flags: 2325 * VM_ALLOC_NOBUSY do not exclusive busy the page 2326 * VM_ALLOC_NODUMP do not include the page in a kernel core dump 2327 * VM_ALLOC_SBUSY shared busy the allocated page 2328 * VM_ALLOC_WIRED wire the allocated page 2329 * VM_ALLOC_ZERO prefer a zeroed page 2330 */ 2331 vm_page_t 2332 vm_page_alloc_contig(vm_object_t object, vm_pindex_t pindex, int req, 2333 u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, 2334 vm_paddr_t boundary, vm_memattr_t memattr) 2335 { 2336 struct vm_domainset_iter di; 2337 vm_page_t bounds[2]; 2338 vm_page_t m; 2339 int domain; 2340 int start_segind; 2341 2342 start_segind = -1; 2343 2344 vm_domainset_iter_page_init(&di, object, pindex, &domain, &req); 2345 do { 2346 m = vm_page_alloc_contig_domain(object, pindex, domain, req, 2347 npages, low, high, alignment, boundary, memattr); 2348 if (m != NULL) 2349 break; 2350 if (start_segind == -1) 2351 start_segind = vm_phys_lookup_segind(low); 2352 if (vm_phys_find_range(bounds, start_segind, domain, 2353 npages, low, high) == -1) { 2354 vm_domainset_iter_ignore(&di, domain); 2355 } 2356 } while (vm_domainset_iter_page(&di, object, &domain) == 0); 2357 2358 return (m); 2359 } 2360 2361 static vm_page_t 2362 vm_page_find_contig_domain(int domain, int req, u_long npages, vm_paddr_t low, 2363 vm_paddr_t high, u_long alignment, vm_paddr_t boundary) 2364 { 2365 struct vm_domain *vmd; 2366 vm_page_t m_ret; 2367 2368 /* 2369 * Can we allocate the pages without the number of free pages falling 2370 * below the lower bound for the allocation class? 2371 */ 2372 vmd = VM_DOMAIN(domain); 2373 if (!vm_domain_allocate(vmd, req, npages)) 2374 return (NULL); 2375 /* 2376 * Try to allocate the pages from the free page queues. 2377 */ 2378 vm_domain_free_lock(vmd); 2379 m_ret = vm_phys_alloc_contig(domain, npages, low, high, 2380 alignment, boundary); 2381 vm_domain_free_unlock(vmd); 2382 if (m_ret != NULL) 2383 return (m_ret); 2384 #if VM_NRESERVLEVEL > 0 2385 /* 2386 * Try to break a reservation to allocate the pages. 2387 */ 2388 if ((req & VM_ALLOC_NORECLAIM) == 0) { 2389 m_ret = vm_reserv_reclaim_contig(domain, npages, low, 2390 high, alignment, boundary); 2391 if (m_ret != NULL) 2392 return (m_ret); 2393 } 2394 #endif 2395 vm_domain_freecnt_inc(vmd, npages); 2396 return (NULL); 2397 } 2398 2399 vm_page_t 2400 vm_page_alloc_contig_domain(vm_object_t object, vm_pindex_t pindex, int domain, 2401 int req, u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment, 2402 vm_paddr_t boundary, vm_memattr_t memattr) 2403 { 2404 struct pctrie_iter pages; 2405 vm_page_t m, m_ret, mpred; 2406 u_int busy_lock, flags, oflags; 2407 2408 #define VPAC_FLAGS (VPA_FLAGS | VM_ALLOC_NORECLAIM) 2409 KASSERT((req & ~VPAC_FLAGS) == 0, 2410 ("invalid request %#x", req)); 2411 KASSERT(((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 2412 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 2413 ("invalid request %#x", req)); 2414 KASSERT((req & (VM_ALLOC_WAITOK | VM_ALLOC_NORECLAIM)) != 2415 (VM_ALLOC_WAITOK | VM_ALLOC_NORECLAIM), 2416 ("invalid request %#x", req)); 2417 VM_OBJECT_ASSERT_WLOCKED(object); 2418 KASSERT((object->flags & OBJ_FICTITIOUS) == 0, 2419 ("vm_page_alloc_contig: object %p has fictitious pages", 2420 object)); 2421 KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero")); 2422 2423 vm_page_iter_init(&pages, object); 2424 mpred = vm_radix_iter_lookup_le(&pages, pindex); 2425 KASSERT(mpred == NULL || mpred->pindex != pindex, 2426 ("vm_page_alloc_contig: pindex already allocated")); 2427 for (;;) { 2428 #if VM_NRESERVLEVEL > 0 2429 /* 2430 * Can we allocate the pages from a reservation? 2431 */ 2432 if (vm_object_reserv(object) && 2433 (m_ret = vm_reserv_alloc_contig(object, pindex, domain, req, 2434 mpred, npages, low, high, alignment, boundary)) != NULL) { 2435 break; 2436 } 2437 #endif 2438 if ((m_ret = vm_page_find_contig_domain(domain, req, npages, 2439 low, high, alignment, boundary)) != NULL) 2440 break; 2441 if (!vm_domain_alloc_fail(VM_DOMAIN(domain), object, req)) 2442 return (NULL); 2443 } 2444 2445 /* 2446 * Initialize the pages. Only the PG_ZERO flag is inherited. 2447 */ 2448 flags = PG_ZERO; 2449 if ((req & VM_ALLOC_NODUMP) != 0) 2450 flags |= PG_NODUMP; 2451 oflags = (object->flags & OBJ_UNMANAGED) != 0 ? VPO_UNMANAGED : 0; 2452 if ((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) == 0) 2453 busy_lock = VPB_CURTHREAD_EXCLUSIVE; 2454 else if ((req & VM_ALLOC_SBUSY) != 0) 2455 busy_lock = VPB_SHARERS_WORD(1); 2456 else 2457 busy_lock = VPB_UNBUSIED; 2458 if ((req & VM_ALLOC_WIRED) != 0) 2459 vm_wire_add(npages); 2460 if (object->memattr != VM_MEMATTR_DEFAULT && 2461 memattr == VM_MEMATTR_DEFAULT) 2462 memattr = object->memattr; 2463 for (m = m_ret; m < &m_ret[npages]; m++) { 2464 vm_page_dequeue(m); 2465 vm_page_alloc_check(m); 2466 m->a.flags = 0; 2467 m->flags = (m->flags | PG_NODUMP) & flags; 2468 m->busy_lock = busy_lock; 2469 if ((req & VM_ALLOC_WIRED) != 0) 2470 m->ref_count = 1; 2471 m->a.act_count = 0; 2472 m->oflags = oflags; 2473 if (vm_page_iter_insert(&pages, m, object, pindex, mpred)) { 2474 if ((req & VM_ALLOC_WIRED) != 0) 2475 vm_wire_sub(npages); 2476 KASSERT(m->object == NULL, 2477 ("page %p has object", m)); 2478 mpred = m; 2479 for (m = m_ret; m < &m_ret[npages]; m++) { 2480 if (m <= mpred && 2481 (req & VM_ALLOC_WIRED) != 0) 2482 m->ref_count = 0; 2483 m->oflags = VPO_UNMANAGED; 2484 m->busy_lock = VPB_UNBUSIED; 2485 /* Don't change PG_ZERO. */ 2486 vm_page_free_toq(m); 2487 } 2488 if (req & VM_ALLOC_WAITFAIL) { 2489 VM_OBJECT_WUNLOCK(object); 2490 vm_radix_wait(); 2491 VM_OBJECT_WLOCK(object); 2492 } 2493 return (NULL); 2494 } 2495 mpred = m; 2496 if (memattr != VM_MEMATTR_DEFAULT) 2497 pmap_page_set_memattr(m, memattr); 2498 pindex++; 2499 } 2500 return (m_ret); 2501 } 2502 2503 /* 2504 * Allocate a physical page that is not intended to be inserted into a VM 2505 * object. 2506 */ 2507 vm_page_t 2508 vm_page_alloc_noobj_domain(int domain, int req) 2509 { 2510 struct vm_domain *vmd; 2511 vm_page_t m; 2512 int flags; 2513 2514 #define VPAN_FLAGS (VM_ALLOC_CLASS_MASK | VM_ALLOC_WAITFAIL | \ 2515 VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | \ 2516 VM_ALLOC_NOBUSY | VM_ALLOC_WIRED | \ 2517 VM_ALLOC_NODUMP | VM_ALLOC_ZERO | \ 2518 VM_ALLOC_NOFREE | VM_ALLOC_COUNT_MASK) 2519 KASSERT((req & ~VPAN_FLAGS) == 0, 2520 ("invalid request %#x", req)); 2521 2522 flags = ((req & VM_ALLOC_NODUMP) != 0 ? PG_NODUMP : 0) | 2523 ((req & VM_ALLOC_NOFREE) != 0 ? PG_NOFREE : 0); 2524 vmd = VM_DOMAIN(domain); 2525 again: 2526 if (__predict_false((req & VM_ALLOC_NOFREE) != 0)) { 2527 m = vm_page_alloc_nofree_domain(domain, req); 2528 if (m != NULL) 2529 goto found; 2530 } 2531 2532 if (vmd->vmd_pgcache[VM_FREEPOOL_DIRECT].zone != NULL) { 2533 m = uma_zalloc(vmd->vmd_pgcache[VM_FREEPOOL_DIRECT].zone, 2534 M_NOWAIT | M_NOVM); 2535 if (m != NULL) { 2536 flags |= PG_PCPU_CACHE; 2537 goto found; 2538 } 2539 } 2540 2541 if (vm_domain_allocate(vmd, req, 1)) { 2542 vm_domain_free_lock(vmd); 2543 m = vm_phys_alloc_pages(domain, VM_FREEPOOL_DIRECT, 0); 2544 vm_domain_free_unlock(vmd); 2545 if (m == NULL) { 2546 vm_domain_freecnt_inc(vmd, 1); 2547 #if VM_NRESERVLEVEL > 0 2548 if (vm_reserv_reclaim_inactive(domain)) 2549 goto again; 2550 #endif 2551 } 2552 } 2553 if (m == NULL) { 2554 if (vm_domain_alloc_fail(vmd, NULL, req)) 2555 goto again; 2556 return (NULL); 2557 } 2558 2559 found: 2560 vm_page_dequeue(m); 2561 vm_page_alloc_check(m); 2562 2563 /* 2564 * Consumers should not rely on a useful default pindex value. 2565 */ 2566 m->pindex = 0xdeadc0dedeadc0de; 2567 m->flags = (m->flags & PG_ZERO) | flags; 2568 m->a.flags = 0; 2569 m->oflags = VPO_UNMANAGED; 2570 m->busy_lock = VPB_UNBUSIED; 2571 if ((req & VM_ALLOC_WIRED) != 0) { 2572 vm_wire_add(1); 2573 m->ref_count = 1; 2574 } 2575 2576 if ((req & VM_ALLOC_ZERO) != 0 && (m->flags & PG_ZERO) == 0) 2577 pmap_zero_page(m); 2578 2579 return (m); 2580 } 2581 2582 #if VM_NRESERVLEVEL > 1 2583 #define VM_NOFREE_IMPORT_ORDER (VM_LEVEL_1_ORDER + VM_LEVEL_0_ORDER) 2584 #elif VM_NRESERVLEVEL > 0 2585 #define VM_NOFREE_IMPORT_ORDER VM_LEVEL_0_ORDER 2586 #else 2587 #define VM_NOFREE_IMPORT_ORDER 8 2588 #endif 2589 2590 /* 2591 * Allocate a single NOFREE page. 2592 * 2593 * This routine hands out NOFREE pages from higher-order 2594 * physical memory blocks in order to reduce memory fragmentation. 2595 * When a NOFREE for a given domain chunk is used up, 2596 * the routine will try to fetch a new one from the freelists 2597 * and discard the old one. 2598 */ 2599 static vm_page_t 2600 vm_page_alloc_nofree_domain(int domain, int req) 2601 { 2602 vm_page_t m; 2603 struct vm_domain *vmd; 2604 struct vm_nofreeq *nqp; 2605 2606 KASSERT((req & VM_ALLOC_NOFREE) != 0, ("invalid request %#x", req)); 2607 2608 vmd = VM_DOMAIN(domain); 2609 nqp = &vmd->vmd_nofreeq; 2610 vm_domain_free_lock(vmd); 2611 if (nqp->offs >= (1 << VM_NOFREE_IMPORT_ORDER) || nqp->ma == NULL) { 2612 if (!vm_domain_allocate(vmd, req, 2613 1 << VM_NOFREE_IMPORT_ORDER)) { 2614 vm_domain_free_unlock(vmd); 2615 return (NULL); 2616 } 2617 nqp->ma = vm_phys_alloc_pages(domain, VM_FREEPOOL_DEFAULT, 2618 VM_NOFREE_IMPORT_ORDER); 2619 if (nqp->ma == NULL) { 2620 vm_domain_freecnt_inc(vmd, 1 << VM_NOFREE_IMPORT_ORDER); 2621 vm_domain_free_unlock(vmd); 2622 return (NULL); 2623 } 2624 nqp->offs = 0; 2625 } 2626 m = &nqp->ma[nqp->offs++]; 2627 vm_domain_free_unlock(vmd); 2628 VM_CNT_ADD(v_nofree_count, 1); 2629 2630 return (m); 2631 } 2632 2633 vm_page_t 2634 vm_page_alloc_noobj(int req) 2635 { 2636 struct vm_domainset_iter di; 2637 vm_page_t m; 2638 int domain; 2639 2640 vm_domainset_iter_page_init(&di, NULL, 0, &domain, &req); 2641 do { 2642 m = vm_page_alloc_noobj_domain(domain, req); 2643 if (m != NULL) 2644 break; 2645 } while (vm_domainset_iter_page(&di, NULL, &domain) == 0); 2646 2647 return (m); 2648 } 2649 2650 vm_page_t 2651 vm_page_alloc_noobj_contig(int req, u_long npages, vm_paddr_t low, 2652 vm_paddr_t high, u_long alignment, vm_paddr_t boundary, 2653 vm_memattr_t memattr) 2654 { 2655 struct vm_domainset_iter di; 2656 vm_page_t m; 2657 int domain; 2658 2659 vm_domainset_iter_page_init(&di, NULL, 0, &domain, &req); 2660 do { 2661 m = vm_page_alloc_noobj_contig_domain(domain, req, npages, low, 2662 high, alignment, boundary, memattr); 2663 if (m != NULL) 2664 break; 2665 } while (vm_domainset_iter_page(&di, NULL, &domain) == 0); 2666 2667 return (m); 2668 } 2669 2670 vm_page_t 2671 vm_page_alloc_noobj_contig_domain(int domain, int req, u_long npages, 2672 vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary, 2673 vm_memattr_t memattr) 2674 { 2675 vm_page_t m, m_ret; 2676 u_int flags; 2677 2678 #define VPANC_FLAGS (VPAN_FLAGS | VM_ALLOC_NORECLAIM) 2679 KASSERT((req & ~VPANC_FLAGS) == 0, 2680 ("invalid request %#x", req)); 2681 KASSERT((req & (VM_ALLOC_WAITOK | VM_ALLOC_NORECLAIM)) != 2682 (VM_ALLOC_WAITOK | VM_ALLOC_NORECLAIM), 2683 ("invalid request %#x", req)); 2684 KASSERT(((req & (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)) != 2685 (VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY)), 2686 ("invalid request %#x", req)); 2687 KASSERT(npages > 0, ("vm_page_alloc_contig: npages is zero")); 2688 2689 while ((m_ret = vm_page_find_contig_domain(domain, req, npages, 2690 low, high, alignment, boundary)) == NULL) { 2691 if (!vm_domain_alloc_fail(VM_DOMAIN(domain), NULL, req)) 2692 return (NULL); 2693 } 2694 2695 /* 2696 * Initialize the pages. Only the PG_ZERO flag is inherited. 2697 */ 2698 flags = PG_ZERO; 2699 if ((req & VM_ALLOC_NODUMP) != 0) 2700 flags |= PG_NODUMP; 2701 if ((req & VM_ALLOC_WIRED) != 0) 2702 vm_wire_add(npages); 2703 for (m = m_ret; m < &m_ret[npages]; m++) { 2704 vm_page_dequeue(m); 2705 vm_page_alloc_check(m); 2706 2707 /* 2708 * Consumers should not rely on a useful default pindex value. 2709 */ 2710 m->pindex = 0xdeadc0dedeadc0de; 2711 m->a.flags = 0; 2712 m->flags = (m->flags | PG_NODUMP) & flags; 2713 m->busy_lock = VPB_UNBUSIED; 2714 if ((req & VM_ALLOC_WIRED) != 0) 2715 m->ref_count = 1; 2716 m->a.act_count = 0; 2717 m->oflags = VPO_UNMANAGED; 2718 2719 /* 2720 * Zero the page before updating any mappings since the page is 2721 * not yet shared with any devices which might require the 2722 * non-default memory attribute. pmap_page_set_memattr() 2723 * flushes data caches before returning. 2724 */ 2725 if ((req & VM_ALLOC_ZERO) != 0 && (m->flags & PG_ZERO) == 0) 2726 pmap_zero_page(m); 2727 if (memattr != VM_MEMATTR_DEFAULT) 2728 pmap_page_set_memattr(m, memattr); 2729 } 2730 return (m_ret); 2731 } 2732 2733 /* 2734 * Check a page that has been freshly dequeued from a freelist. 2735 */ 2736 static void 2737 vm_page_alloc_check(vm_page_t m) 2738 { 2739 2740 KASSERT(m->object == NULL, ("page %p has object", m)); 2741 KASSERT(m->a.queue == PQ_NONE && 2742 (m->a.flags & PGA_QUEUE_STATE_MASK) == 0, 2743 ("page %p has unexpected queue %d, flags %#x", 2744 m, m->a.queue, (m->a.flags & PGA_QUEUE_STATE_MASK))); 2745 KASSERT(m->ref_count == 0, ("page %p has references", m)); 2746 KASSERT(vm_page_busy_freed(m), ("page %p is not freed", m)); 2747 KASSERT(m->dirty == 0, ("page %p is dirty", m)); 2748 KASSERT(pmap_page_get_memattr(m) == VM_MEMATTR_DEFAULT, 2749 ("page %p has unexpected memattr %d", 2750 m, pmap_page_get_memattr(m))); 2751 KASSERT(vm_page_none_valid(m), ("free page %p is valid", m)); 2752 pmap_vm_page_alloc_check(m); 2753 } 2754 2755 static int 2756 vm_page_zone_import(void *arg, void **store, int cnt, int domain, int flags) 2757 { 2758 struct vm_domain *vmd; 2759 struct vm_pgcache *pgcache; 2760 int i; 2761 2762 pgcache = arg; 2763 vmd = VM_DOMAIN(pgcache->domain); 2764 2765 /* 2766 * The page daemon should avoid creating extra memory pressure since its 2767 * main purpose is to replenish the store of free pages. 2768 */ 2769 if (vmd->vmd_severeset || curproc == pageproc || 2770 !_vm_domain_allocate(vmd, VM_ALLOC_NORMAL, cnt)) 2771 return (0); 2772 domain = vmd->vmd_domain; 2773 vm_domain_free_lock(vmd); 2774 i = vm_phys_alloc_npages(domain, pgcache->pool, cnt, 2775 (vm_page_t *)store); 2776 vm_domain_free_unlock(vmd); 2777 if (cnt != i) 2778 vm_domain_freecnt_inc(vmd, cnt - i); 2779 2780 return (i); 2781 } 2782 2783 static void 2784 vm_page_zone_release(void *arg, void **store, int cnt) 2785 { 2786 struct vm_domain *vmd; 2787 struct vm_pgcache *pgcache; 2788 vm_page_t m; 2789 int i; 2790 2791 pgcache = arg; 2792 vmd = VM_DOMAIN(pgcache->domain); 2793 vm_domain_free_lock(vmd); 2794 for (i = 0; i < cnt; i++) { 2795 m = (vm_page_t)store[i]; 2796 vm_phys_free_pages(m, 0); 2797 } 2798 vm_domain_free_unlock(vmd); 2799 vm_domain_freecnt_inc(vmd, cnt); 2800 } 2801 2802 #define VPSC_ANY 0 /* No restrictions. */ 2803 #define VPSC_NORESERV 1 /* Skip reservations; implies VPSC_NOSUPER. */ 2804 #define VPSC_NOSUPER 2 /* Skip superpages. */ 2805 2806 /* 2807 * vm_page_scan_contig: 2808 * 2809 * Scan vm_page_array[] between the specified entries "m_start" and 2810 * "m_end" for a run of contiguous physical pages that satisfy the 2811 * specified conditions, and return the lowest page in the run. The 2812 * specified "alignment" determines the alignment of the lowest physical 2813 * page in the run. If the specified "boundary" is non-zero, then the 2814 * run of physical pages cannot span a physical address that is a 2815 * multiple of "boundary". 2816 * 2817 * "m_end" is never dereferenced, so it need not point to a vm_page 2818 * structure within vm_page_array[]. 2819 * 2820 * "npages" must be greater than zero. "m_start" and "m_end" must not 2821 * span a hole (or discontiguity) in the physical address space. Both 2822 * "alignment" and "boundary" must be a power of two. 2823 */ 2824 static vm_page_t 2825 vm_page_scan_contig(u_long npages, vm_page_t m_start, vm_page_t m_end, 2826 u_long alignment, vm_paddr_t boundary, int options) 2827 { 2828 vm_object_t object; 2829 vm_paddr_t pa; 2830 vm_page_t m, m_run; 2831 #if VM_NRESERVLEVEL > 0 2832 int level; 2833 #endif 2834 int m_inc, order, run_ext, run_len; 2835 2836 KASSERT(npages > 0, ("npages is 0")); 2837 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 2838 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 2839 m_run = NULL; 2840 run_len = 0; 2841 for (m = m_start; m < m_end && run_len < npages; m += m_inc) { 2842 KASSERT((m->flags & PG_MARKER) == 0, 2843 ("page %p is PG_MARKER", m)); 2844 KASSERT((m->flags & PG_FICTITIOUS) == 0 || m->ref_count >= 1, 2845 ("fictitious page %p has invalid ref count", m)); 2846 2847 /* 2848 * If the current page would be the start of a run, check its 2849 * physical address against the end, alignment, and boundary 2850 * conditions. If it doesn't satisfy these conditions, either 2851 * terminate the scan or advance to the next page that 2852 * satisfies the failed condition. 2853 */ 2854 if (run_len == 0) { 2855 KASSERT(m_run == NULL, ("m_run != NULL")); 2856 if (m + npages > m_end) 2857 break; 2858 pa = VM_PAGE_TO_PHYS(m); 2859 if (!vm_addr_align_ok(pa, alignment)) { 2860 m_inc = atop(roundup2(pa, alignment) - pa); 2861 continue; 2862 } 2863 if (!vm_addr_bound_ok(pa, ptoa(npages), boundary)) { 2864 m_inc = atop(roundup2(pa, boundary) - pa); 2865 continue; 2866 } 2867 } else 2868 KASSERT(m_run != NULL, ("m_run == NULL")); 2869 2870 retry: 2871 m_inc = 1; 2872 if (vm_page_wired(m)) 2873 run_ext = 0; 2874 #if VM_NRESERVLEVEL > 0 2875 else if ((level = vm_reserv_level(m)) >= 0 && 2876 (options & VPSC_NORESERV) != 0) { 2877 run_ext = 0; 2878 /* Advance to the end of the reservation. */ 2879 pa = VM_PAGE_TO_PHYS(m); 2880 m_inc = atop(roundup2(pa + 1, vm_reserv_size(level)) - 2881 pa); 2882 } 2883 #endif 2884 else if ((object = atomic_load_ptr(&m->object)) != NULL) { 2885 /* 2886 * The page is considered eligible for relocation if 2887 * and only if it could be laundered or reclaimed by 2888 * the page daemon. 2889 */ 2890 VM_OBJECT_RLOCK(object); 2891 if (object != m->object) { 2892 VM_OBJECT_RUNLOCK(object); 2893 goto retry; 2894 } 2895 /* Don't care: PG_NODUMP, PG_ZERO. */ 2896 if ((object->flags & OBJ_SWAP) == 0 && 2897 object->type != OBJT_VNODE) { 2898 run_ext = 0; 2899 #if VM_NRESERVLEVEL > 0 2900 } else if ((options & VPSC_NOSUPER) != 0 && 2901 (level = vm_reserv_level_iffullpop(m)) >= 0) { 2902 run_ext = 0; 2903 /* Advance to the end of the superpage. */ 2904 pa = VM_PAGE_TO_PHYS(m); 2905 m_inc = atop(roundup2(pa + 1, 2906 vm_reserv_size(level)) - pa); 2907 #endif 2908 } else if (object->memattr == VM_MEMATTR_DEFAULT && 2909 vm_page_queue(m) != PQ_NONE && !vm_page_busied(m)) { 2910 /* 2911 * The page is allocated but eligible for 2912 * relocation. Extend the current run by one 2913 * page. 2914 */ 2915 KASSERT(pmap_page_get_memattr(m) == 2916 VM_MEMATTR_DEFAULT, 2917 ("page %p has an unexpected memattr", m)); 2918 KASSERT((m->oflags & (VPO_SWAPINPROG | 2919 VPO_SWAPSLEEP | VPO_UNMANAGED)) == 0, 2920 ("page %p has unexpected oflags", m)); 2921 /* Don't care: PGA_NOSYNC. */ 2922 run_ext = 1; 2923 } else 2924 run_ext = 0; 2925 VM_OBJECT_RUNLOCK(object); 2926 #if VM_NRESERVLEVEL > 0 2927 } else if (level >= 0) { 2928 /* 2929 * The page is reserved but not yet allocated. In 2930 * other words, it is still free. Extend the current 2931 * run by one page. 2932 */ 2933 run_ext = 1; 2934 #endif 2935 } else if ((order = m->order) < VM_NFREEORDER) { 2936 /* 2937 * The page is enqueued in the physical memory 2938 * allocator's free page queues. Moreover, it is the 2939 * first page in a power-of-two-sized run of 2940 * contiguous free pages. Add these pages to the end 2941 * of the current run, and jump ahead. 2942 */ 2943 run_ext = 1 << order; 2944 m_inc = 1 << order; 2945 } else { 2946 /* 2947 * Skip the page for one of the following reasons: (1) 2948 * It is enqueued in the physical memory allocator's 2949 * free page queues. However, it is not the first 2950 * page in a run of contiguous free pages. (This case 2951 * rarely occurs because the scan is performed in 2952 * ascending order.) (2) It is not reserved, and it is 2953 * transitioning from free to allocated. (Conversely, 2954 * the transition from allocated to free for managed 2955 * pages is blocked by the page busy lock.) (3) It is 2956 * allocated but not contained by an object and not 2957 * wired, e.g., allocated by Xen's balloon driver. 2958 */ 2959 run_ext = 0; 2960 } 2961 2962 /* 2963 * Extend or reset the current run of pages. 2964 */ 2965 if (run_ext > 0) { 2966 if (run_len == 0) 2967 m_run = m; 2968 run_len += run_ext; 2969 } else { 2970 if (run_len > 0) { 2971 m_run = NULL; 2972 run_len = 0; 2973 } 2974 } 2975 } 2976 if (run_len >= npages) 2977 return (m_run); 2978 return (NULL); 2979 } 2980 2981 /* 2982 * vm_page_reclaim_run: 2983 * 2984 * Try to relocate each of the allocated virtual pages within the 2985 * specified run of physical pages to a new physical address. Free the 2986 * physical pages underlying the relocated virtual pages. A virtual page 2987 * is relocatable if and only if it could be laundered or reclaimed by 2988 * the page daemon. Whenever possible, a virtual page is relocated to a 2989 * physical address above "high". 2990 * 2991 * Returns 0 if every physical page within the run was already free or 2992 * just freed by a successful relocation. Otherwise, returns a non-zero 2993 * value indicating why the last attempt to relocate a virtual page was 2994 * unsuccessful. 2995 * 2996 * "req_class" must be an allocation class. 2997 */ 2998 static int 2999 vm_page_reclaim_run(int req_class, int domain, u_long npages, vm_page_t m_run, 3000 vm_paddr_t high) 3001 { 3002 struct vm_domain *vmd; 3003 struct spglist free; 3004 vm_object_t object; 3005 vm_paddr_t pa; 3006 vm_page_t m, m_end, m_new; 3007 int error, order, req; 3008 3009 KASSERT((req_class & VM_ALLOC_CLASS_MASK) == req_class, 3010 ("req_class is not an allocation class")); 3011 SLIST_INIT(&free); 3012 error = 0; 3013 m = m_run; 3014 m_end = m_run + npages; 3015 for (; error == 0 && m < m_end; m++) { 3016 KASSERT((m->flags & (PG_FICTITIOUS | PG_MARKER)) == 0, 3017 ("page %p is PG_FICTITIOUS or PG_MARKER", m)); 3018 3019 /* 3020 * Racily check for wirings. Races are handled once the object 3021 * lock is held and the page is unmapped. 3022 */ 3023 if (vm_page_wired(m)) 3024 error = EBUSY; 3025 else if ((object = atomic_load_ptr(&m->object)) != NULL) { 3026 /* 3027 * The page is relocated if and only if it could be 3028 * laundered or reclaimed by the page daemon. 3029 */ 3030 VM_OBJECT_WLOCK(object); 3031 /* Don't care: PG_NODUMP, PG_ZERO. */ 3032 if (m->object != object || 3033 ((object->flags & OBJ_SWAP) == 0 && 3034 object->type != OBJT_VNODE)) 3035 error = EINVAL; 3036 else if (object->memattr != VM_MEMATTR_DEFAULT) 3037 error = EINVAL; 3038 else if (vm_page_queue(m) != PQ_NONE && 3039 vm_page_tryxbusy(m) != 0) { 3040 if (vm_page_wired(m)) { 3041 vm_page_xunbusy(m); 3042 error = EBUSY; 3043 goto unlock; 3044 } 3045 KASSERT(pmap_page_get_memattr(m) == 3046 VM_MEMATTR_DEFAULT, 3047 ("page %p has an unexpected memattr", m)); 3048 KASSERT(m->oflags == 0, 3049 ("page %p has unexpected oflags", m)); 3050 /* Don't care: PGA_NOSYNC. */ 3051 if (!vm_page_none_valid(m)) { 3052 /* 3053 * First, try to allocate a new page 3054 * that is above "high". Failing 3055 * that, try to allocate a new page 3056 * that is below "m_run". Allocate 3057 * the new page between the end of 3058 * "m_run" and "high" only as a last 3059 * resort. 3060 */ 3061 req = req_class; 3062 if ((m->flags & PG_NODUMP) != 0) 3063 req |= VM_ALLOC_NODUMP; 3064 if (trunc_page(high) != 3065 ~(vm_paddr_t)PAGE_MASK) { 3066 m_new = 3067 vm_page_alloc_noobj_contig( 3068 req, 1, round_page(high), 3069 ~(vm_paddr_t)0, PAGE_SIZE, 3070 0, VM_MEMATTR_DEFAULT); 3071 } else 3072 m_new = NULL; 3073 if (m_new == NULL) { 3074 pa = VM_PAGE_TO_PHYS(m_run); 3075 m_new = 3076 vm_page_alloc_noobj_contig( 3077 req, 1, 0, pa - 1, 3078 PAGE_SIZE, 0, 3079 VM_MEMATTR_DEFAULT); 3080 } 3081 if (m_new == NULL) { 3082 pa += ptoa(npages); 3083 m_new = 3084 vm_page_alloc_noobj_contig( 3085 req, 1, pa, high, PAGE_SIZE, 3086 0, VM_MEMATTR_DEFAULT); 3087 } 3088 if (m_new == NULL) { 3089 vm_page_xunbusy(m); 3090 error = ENOMEM; 3091 goto unlock; 3092 } 3093 3094 /* 3095 * Unmap the page and check for new 3096 * wirings that may have been acquired 3097 * through a pmap lookup. 3098 */ 3099 if (object->ref_count != 0 && 3100 !vm_page_try_remove_all(m)) { 3101 vm_page_xunbusy(m); 3102 vm_page_free(m_new); 3103 error = EBUSY; 3104 goto unlock; 3105 } 3106 3107 /* 3108 * Replace "m" with the new page. For 3109 * vm_page_replace(), "m" must be busy 3110 * and dequeued. Finally, change "m" 3111 * as if vm_page_free() was called. 3112 */ 3113 m_new->a.flags = m->a.flags & 3114 ~PGA_QUEUE_STATE_MASK; 3115 KASSERT(m_new->oflags == VPO_UNMANAGED, 3116 ("page %p is managed", m_new)); 3117 m_new->oflags = 0; 3118 pmap_copy_page(m, m_new); 3119 m_new->valid = m->valid; 3120 m_new->dirty = m->dirty; 3121 m->flags &= ~PG_ZERO; 3122 vm_page_dequeue(m); 3123 if (vm_page_replace_hold(m_new, object, 3124 m->pindex, m) && 3125 vm_page_free_prep(m)) 3126 SLIST_INSERT_HEAD(&free, m, 3127 plinks.s.ss); 3128 3129 /* 3130 * The new page must be deactivated 3131 * before the object is unlocked. 3132 */ 3133 vm_page_deactivate(m_new); 3134 } else { 3135 m->flags &= ~PG_ZERO; 3136 vm_page_dequeue(m); 3137 if (vm_page_free_prep(m)) 3138 SLIST_INSERT_HEAD(&free, m, 3139 plinks.s.ss); 3140 KASSERT(m->dirty == 0, 3141 ("page %p is dirty", m)); 3142 } 3143 } else 3144 error = EBUSY; 3145 unlock: 3146 VM_OBJECT_WUNLOCK(object); 3147 } else { 3148 MPASS(vm_page_domain(m) == domain); 3149 vmd = VM_DOMAIN(domain); 3150 vm_domain_free_lock(vmd); 3151 order = m->order; 3152 if (order < VM_NFREEORDER) { 3153 /* 3154 * The page is enqueued in the physical memory 3155 * allocator's free page queues. Moreover, it 3156 * is the first page in a power-of-two-sized 3157 * run of contiguous free pages. Jump ahead 3158 * to the last page within that run, and 3159 * continue from there. 3160 */ 3161 m += (1 << order) - 1; 3162 } 3163 #if VM_NRESERVLEVEL > 0 3164 else if (vm_reserv_is_page_free(m)) 3165 order = 0; 3166 #endif 3167 vm_domain_free_unlock(vmd); 3168 if (order == VM_NFREEORDER) 3169 error = EINVAL; 3170 } 3171 } 3172 if ((m = SLIST_FIRST(&free)) != NULL) { 3173 int cnt; 3174 3175 vmd = VM_DOMAIN(domain); 3176 cnt = 0; 3177 vm_domain_free_lock(vmd); 3178 do { 3179 MPASS(vm_page_domain(m) == domain); 3180 SLIST_REMOVE_HEAD(&free, plinks.s.ss); 3181 vm_phys_free_pages(m, 0); 3182 cnt++; 3183 } while ((m = SLIST_FIRST(&free)) != NULL); 3184 vm_domain_free_unlock(vmd); 3185 vm_domain_freecnt_inc(vmd, cnt); 3186 } 3187 return (error); 3188 } 3189 3190 #define NRUNS 16 3191 3192 #define RUN_INDEX(count, nruns) ((count) % (nruns)) 3193 3194 #define MIN_RECLAIM 8 3195 3196 /* 3197 * vm_page_reclaim_contig: 3198 * 3199 * Reclaim allocated, contiguous physical memory satisfying the specified 3200 * conditions by relocating the virtual pages using that physical memory. 3201 * Returns 0 if reclamation is successful, ERANGE if the specified domain 3202 * can't possibly satisfy the reclamation request, or ENOMEM if not 3203 * currently able to reclaim the requested number of pages. Since 3204 * relocation requires the allocation of physical pages, reclamation may 3205 * fail with ENOMEM due to a shortage of free pages. When reclamation 3206 * fails in this manner, callers are expected to perform vm_wait() before 3207 * retrying a failed allocation operation, e.g., vm_page_alloc_contig(). 3208 * 3209 * The caller must always specify an allocation class through "req". 3210 * 3211 * allocation classes: 3212 * VM_ALLOC_NORMAL normal process request 3213 * VM_ALLOC_SYSTEM system *really* needs a page 3214 * VM_ALLOC_INTERRUPT interrupt time request 3215 * 3216 * The optional allocation flags are ignored. 3217 * 3218 * "npages" must be greater than zero. Both "alignment" and "boundary" 3219 * must be a power of two. 3220 */ 3221 int 3222 vm_page_reclaim_contig_domain_ext(int domain, int req, u_long npages, 3223 vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary, 3224 int desired_runs) 3225 { 3226 struct vm_domain *vmd; 3227 vm_page_t bounds[2], m_run, _m_runs[NRUNS], *m_runs; 3228 u_long count, minalign, reclaimed; 3229 int error, i, min_reclaim, nruns, options, req_class; 3230 int segind, start_segind; 3231 int ret; 3232 3233 KASSERT(npages > 0, ("npages is 0")); 3234 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 3235 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 3236 3237 ret = ENOMEM; 3238 3239 /* 3240 * If the caller wants to reclaim multiple runs, try to allocate 3241 * space to store the runs. If that fails, fall back to the old 3242 * behavior of just reclaiming MIN_RECLAIM pages. 3243 */ 3244 if (desired_runs > 1) 3245 m_runs = malloc((NRUNS + desired_runs) * sizeof(*m_runs), 3246 M_TEMP, M_NOWAIT); 3247 else 3248 m_runs = NULL; 3249 3250 if (m_runs == NULL) { 3251 m_runs = _m_runs; 3252 nruns = NRUNS; 3253 } else { 3254 nruns = NRUNS + desired_runs - 1; 3255 } 3256 min_reclaim = MAX(desired_runs * npages, MIN_RECLAIM); 3257 3258 /* 3259 * The caller will attempt an allocation after some runs have been 3260 * reclaimed and added to the vm_phys buddy lists. Due to limitations 3261 * of vm_phys_alloc_contig(), round up the requested length to the next 3262 * power of two or maximum chunk size, and ensure that each run is 3263 * suitably aligned. 3264 */ 3265 minalign = 1ul << imin(flsl(npages - 1), VM_NFREEORDER - 1); 3266 npages = roundup2(npages, minalign); 3267 if (alignment < ptoa(minalign)) 3268 alignment = ptoa(minalign); 3269 3270 /* 3271 * The page daemon is allowed to dig deeper into the free page list. 3272 */ 3273 req_class = req & VM_ALLOC_CLASS_MASK; 3274 if (curproc == pageproc && req_class != VM_ALLOC_INTERRUPT) 3275 req_class = VM_ALLOC_SYSTEM; 3276 3277 start_segind = vm_phys_lookup_segind(low); 3278 3279 /* 3280 * Return if the number of free pages cannot satisfy the requested 3281 * allocation. 3282 */ 3283 vmd = VM_DOMAIN(domain); 3284 count = vmd->vmd_free_count; 3285 if (count < npages + vmd->vmd_free_reserved || (count < npages + 3286 vmd->vmd_interrupt_free_min && req_class == VM_ALLOC_SYSTEM) || 3287 (count < npages && req_class == VM_ALLOC_INTERRUPT)) 3288 goto done; 3289 3290 /* 3291 * Scan up to three times, relaxing the restrictions ("options") on 3292 * the reclamation of reservations and superpages each time. 3293 */ 3294 for (options = VPSC_NORESERV;;) { 3295 bool phys_range_exists = false; 3296 3297 /* 3298 * Find the highest runs that satisfy the given constraints 3299 * and restrictions, and record them in "m_runs". 3300 */ 3301 count = 0; 3302 segind = start_segind; 3303 while ((segind = vm_phys_find_range(bounds, segind, domain, 3304 npages, low, high)) != -1) { 3305 phys_range_exists = true; 3306 while ((m_run = vm_page_scan_contig(npages, bounds[0], 3307 bounds[1], alignment, boundary, options))) { 3308 bounds[0] = m_run + npages; 3309 m_runs[RUN_INDEX(count, nruns)] = m_run; 3310 count++; 3311 } 3312 segind++; 3313 } 3314 3315 if (!phys_range_exists) { 3316 ret = ERANGE; 3317 goto done; 3318 } 3319 3320 /* 3321 * Reclaim the highest runs in LIFO (descending) order until 3322 * the number of reclaimed pages, "reclaimed", is at least 3323 * "min_reclaim". Reset "reclaimed" each time because each 3324 * reclamation is idempotent, and runs will (likely) recur 3325 * from one scan to the next as restrictions are relaxed. 3326 */ 3327 reclaimed = 0; 3328 for (i = 0; count > 0 && i < nruns; i++) { 3329 count--; 3330 m_run = m_runs[RUN_INDEX(count, nruns)]; 3331 error = vm_page_reclaim_run(req_class, domain, npages, 3332 m_run, high); 3333 if (error == 0) { 3334 reclaimed += npages; 3335 if (reclaimed >= min_reclaim) { 3336 ret = 0; 3337 goto done; 3338 } 3339 } 3340 } 3341 3342 /* 3343 * Either relax the restrictions on the next scan or return if 3344 * the last scan had no restrictions. 3345 */ 3346 if (options == VPSC_NORESERV) 3347 options = VPSC_NOSUPER; 3348 else if (options == VPSC_NOSUPER) 3349 options = VPSC_ANY; 3350 else if (options == VPSC_ANY) { 3351 if (reclaimed != 0) 3352 ret = 0; 3353 goto done; 3354 } 3355 } 3356 done: 3357 if (m_runs != _m_runs) 3358 free(m_runs, M_TEMP); 3359 return (ret); 3360 } 3361 3362 int 3363 vm_page_reclaim_contig_domain(int domain, int req, u_long npages, 3364 vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary) 3365 { 3366 return (vm_page_reclaim_contig_domain_ext(domain, req, npages, low, high, 3367 alignment, boundary, 1)); 3368 } 3369 3370 int 3371 vm_page_reclaim_contig(int req, u_long npages, vm_paddr_t low, vm_paddr_t high, 3372 u_long alignment, vm_paddr_t boundary) 3373 { 3374 struct vm_domainset_iter di; 3375 int domain, ret, status; 3376 3377 ret = ERANGE; 3378 3379 vm_domainset_iter_page_init(&di, NULL, 0, &domain, &req); 3380 do { 3381 status = vm_page_reclaim_contig_domain(domain, req, npages, low, 3382 high, alignment, boundary); 3383 if (status == 0) 3384 return (0); 3385 else if (status == ERANGE) 3386 vm_domainset_iter_ignore(&di, domain); 3387 else { 3388 KASSERT(status == ENOMEM, ("Unrecognized error %d " 3389 "from vm_page_reclaim_contig_domain()", status)); 3390 ret = ENOMEM; 3391 } 3392 } while (vm_domainset_iter_page(&di, NULL, &domain) == 0); 3393 3394 return (ret); 3395 } 3396 3397 /* 3398 * Set the domain in the appropriate page level domainset. 3399 */ 3400 void 3401 vm_domain_set(struct vm_domain *vmd) 3402 { 3403 3404 mtx_lock(&vm_domainset_lock); 3405 if (!vmd->vmd_minset && vm_paging_min(vmd)) { 3406 vmd->vmd_minset = 1; 3407 DOMAINSET_SET(vmd->vmd_domain, &vm_min_domains); 3408 } 3409 if (!vmd->vmd_severeset && vm_paging_severe(vmd)) { 3410 vmd->vmd_severeset = 1; 3411 DOMAINSET_SET(vmd->vmd_domain, &vm_severe_domains); 3412 } 3413 mtx_unlock(&vm_domainset_lock); 3414 } 3415 3416 /* 3417 * Clear the domain from the appropriate page level domainset. 3418 */ 3419 void 3420 vm_domain_clear(struct vm_domain *vmd) 3421 { 3422 3423 mtx_lock(&vm_domainset_lock); 3424 if (vmd->vmd_minset && !vm_paging_min(vmd)) { 3425 vmd->vmd_minset = 0; 3426 DOMAINSET_CLR(vmd->vmd_domain, &vm_min_domains); 3427 if (vm_min_waiters != 0) { 3428 vm_min_waiters = 0; 3429 wakeup(&vm_min_domains); 3430 } 3431 } 3432 if (vmd->vmd_severeset && !vm_paging_severe(vmd)) { 3433 vmd->vmd_severeset = 0; 3434 DOMAINSET_CLR(vmd->vmd_domain, &vm_severe_domains); 3435 if (vm_severe_waiters != 0) { 3436 vm_severe_waiters = 0; 3437 wakeup(&vm_severe_domains); 3438 } 3439 } 3440 3441 /* 3442 * If pageout daemon needs pages, then tell it that there are 3443 * some free. 3444 */ 3445 if (vmd->vmd_pageout_pages_needed && 3446 vmd->vmd_free_count >= vmd->vmd_pageout_free_min) { 3447 wakeup(&vmd->vmd_pageout_pages_needed); 3448 vmd->vmd_pageout_pages_needed = 0; 3449 } 3450 3451 /* See comments in vm_wait_doms(). */ 3452 if (vm_pageproc_waiters) { 3453 vm_pageproc_waiters = 0; 3454 wakeup(&vm_pageproc_waiters); 3455 } 3456 mtx_unlock(&vm_domainset_lock); 3457 } 3458 3459 /* 3460 * Wait for free pages to exceed the min threshold globally. 3461 */ 3462 void 3463 vm_wait_min(void) 3464 { 3465 3466 mtx_lock(&vm_domainset_lock); 3467 while (vm_page_count_min()) { 3468 vm_min_waiters++; 3469 msleep(&vm_min_domains, &vm_domainset_lock, PVM, "vmwait", 0); 3470 } 3471 mtx_unlock(&vm_domainset_lock); 3472 } 3473 3474 /* 3475 * Wait for free pages to exceed the severe threshold globally. 3476 */ 3477 void 3478 vm_wait_severe(void) 3479 { 3480 3481 mtx_lock(&vm_domainset_lock); 3482 while (vm_page_count_severe()) { 3483 vm_severe_waiters++; 3484 msleep(&vm_severe_domains, &vm_domainset_lock, PVM, 3485 "vmwait", 0); 3486 } 3487 mtx_unlock(&vm_domainset_lock); 3488 } 3489 3490 u_int 3491 vm_wait_count(void) 3492 { 3493 3494 return (vm_severe_waiters + vm_min_waiters + vm_pageproc_waiters); 3495 } 3496 3497 int 3498 vm_wait_doms(const domainset_t *wdoms, int mflags) 3499 { 3500 int error; 3501 3502 error = 0; 3503 3504 /* 3505 * We use racey wakeup synchronization to avoid expensive global 3506 * locking for the pageproc when sleeping with a non-specific vm_wait. 3507 * To handle this, we only sleep for one tick in this instance. It 3508 * is expected that most allocations for the pageproc will come from 3509 * kmem or vm_page_grab* which will use the more specific and 3510 * race-free vm_wait_domain(). 3511 */ 3512 if (curproc == pageproc) { 3513 mtx_lock(&vm_domainset_lock); 3514 vm_pageproc_waiters++; 3515 error = msleep(&vm_pageproc_waiters, &vm_domainset_lock, 3516 PVM | PDROP | mflags, "pageprocwait", 1); 3517 } else { 3518 /* 3519 * XXX Ideally we would wait only until the allocation could 3520 * be satisfied. This condition can cause new allocators to 3521 * consume all freed pages while old allocators wait. 3522 */ 3523 mtx_lock(&vm_domainset_lock); 3524 if (vm_page_count_min_set(wdoms)) { 3525 if (pageproc == NULL) 3526 panic("vm_wait in early boot"); 3527 vm_min_waiters++; 3528 error = msleep(&vm_min_domains, &vm_domainset_lock, 3529 PVM | PDROP | mflags, "vmwait", 0); 3530 } else 3531 mtx_unlock(&vm_domainset_lock); 3532 } 3533 return (error); 3534 } 3535 3536 /* 3537 * vm_wait_domain: 3538 * 3539 * Sleep until free pages are available for allocation. 3540 * - Called in various places after failed memory allocations. 3541 */ 3542 void 3543 vm_wait_domain(int domain) 3544 { 3545 struct vm_domain *vmd; 3546 domainset_t wdom; 3547 3548 vmd = VM_DOMAIN(domain); 3549 vm_domain_free_assert_unlocked(vmd); 3550 3551 if (curproc == pageproc) { 3552 mtx_lock(&vm_domainset_lock); 3553 if (vmd->vmd_free_count < vmd->vmd_pageout_free_min) { 3554 vmd->vmd_pageout_pages_needed = 1; 3555 msleep(&vmd->vmd_pageout_pages_needed, 3556 &vm_domainset_lock, PDROP | PSWP, "VMWait", 0); 3557 } else 3558 mtx_unlock(&vm_domainset_lock); 3559 } else { 3560 DOMAINSET_ZERO(&wdom); 3561 DOMAINSET_SET(vmd->vmd_domain, &wdom); 3562 vm_wait_doms(&wdom, 0); 3563 } 3564 } 3565 3566 static int 3567 vm_wait_flags(vm_object_t obj, int mflags) 3568 { 3569 struct domainset *d; 3570 3571 d = NULL; 3572 3573 /* 3574 * Carefully fetch pointers only once: the struct domainset 3575 * itself is ummutable but the pointer might change. 3576 */ 3577 if (obj != NULL) 3578 d = obj->domain.dr_policy; 3579 if (d == NULL) 3580 d = curthread->td_domain.dr_policy; 3581 3582 return (vm_wait_doms(&d->ds_mask, mflags)); 3583 } 3584 3585 /* 3586 * vm_wait: 3587 * 3588 * Sleep until free pages are available for allocation in the 3589 * affinity domains of the obj. If obj is NULL, the domain set 3590 * for the calling thread is used. 3591 * Called in various places after failed memory allocations. 3592 */ 3593 void 3594 vm_wait(vm_object_t obj) 3595 { 3596 (void)vm_wait_flags(obj, 0); 3597 } 3598 3599 int 3600 vm_wait_intr(vm_object_t obj) 3601 { 3602 return (vm_wait_flags(obj, PCATCH)); 3603 } 3604 3605 /* 3606 * vm_domain_alloc_fail: 3607 * 3608 * Called when a page allocation function fails. Informs the 3609 * pagedaemon and performs the requested wait. Requires the 3610 * domain_free and object lock on entry. Returns with the 3611 * object lock held and free lock released. Returns an error when 3612 * retry is necessary. 3613 * 3614 */ 3615 static int 3616 vm_domain_alloc_fail(struct vm_domain *vmd, vm_object_t object, int req) 3617 { 3618 3619 vm_domain_free_assert_unlocked(vmd); 3620 3621 atomic_add_int(&vmd->vmd_pageout_deficit, 3622 max((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1)); 3623 if (req & (VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL)) { 3624 if (object != NULL) 3625 VM_OBJECT_WUNLOCK(object); 3626 vm_wait_domain(vmd->vmd_domain); 3627 if (object != NULL) 3628 VM_OBJECT_WLOCK(object); 3629 if (req & VM_ALLOC_WAITOK) 3630 return (EAGAIN); 3631 } 3632 3633 return (0); 3634 } 3635 3636 /* 3637 * vm_waitpfault: 3638 * 3639 * Sleep until free pages are available for allocation. 3640 * - Called only in vm_fault so that processes page faulting 3641 * can be easily tracked. 3642 * - Sleeps at a lower priority than vm_wait() so that vm_wait()ing 3643 * processes will be able to grab memory first. Do not change 3644 * this balance without careful testing first. 3645 */ 3646 void 3647 vm_waitpfault(struct domainset *dset, int timo) 3648 { 3649 3650 /* 3651 * XXX Ideally we would wait only until the allocation could 3652 * be satisfied. This condition can cause new allocators to 3653 * consume all freed pages while old allocators wait. 3654 */ 3655 mtx_lock(&vm_domainset_lock); 3656 if (vm_page_count_min_set(&dset->ds_mask)) { 3657 vm_min_waiters++; 3658 msleep(&vm_min_domains, &vm_domainset_lock, PUSER | PDROP, 3659 "pfault", timo); 3660 } else 3661 mtx_unlock(&vm_domainset_lock); 3662 } 3663 3664 static struct vm_pagequeue * 3665 _vm_page_pagequeue(vm_page_t m, uint8_t queue) 3666 { 3667 3668 return (&vm_pagequeue_domain(m)->vmd_pagequeues[queue]); 3669 } 3670 3671 #ifdef INVARIANTS 3672 static struct vm_pagequeue * 3673 vm_page_pagequeue(vm_page_t m) 3674 { 3675 3676 return (_vm_page_pagequeue(m, vm_page_astate_load(m).queue)); 3677 } 3678 #endif 3679 3680 static __always_inline bool 3681 vm_page_pqstate_fcmpset(vm_page_t m, vm_page_astate_t *old, vm_page_astate_t new) 3682 { 3683 vm_page_astate_t tmp; 3684 3685 tmp = *old; 3686 do { 3687 if (__predict_true(vm_page_astate_fcmpset(m, old, new))) 3688 return (true); 3689 counter_u64_add(pqstate_commit_retries, 1); 3690 } while (old->_bits == tmp._bits); 3691 3692 return (false); 3693 } 3694 3695 /* 3696 * Do the work of committing a queue state update that moves the page out of 3697 * its current queue. 3698 */ 3699 static bool 3700 _vm_page_pqstate_commit_dequeue(struct vm_pagequeue *pq, vm_page_t m, 3701 vm_page_astate_t *old, vm_page_astate_t new) 3702 { 3703 vm_page_t next; 3704 3705 vm_pagequeue_assert_locked(pq); 3706 KASSERT(vm_page_pagequeue(m) == pq, 3707 ("%s: queue %p does not match page %p", __func__, pq, m)); 3708 KASSERT(old->queue != PQ_NONE && new.queue != old->queue, 3709 ("%s: invalid queue indices %d %d", 3710 __func__, old->queue, new.queue)); 3711 3712 /* 3713 * Once the queue index of the page changes there is nothing 3714 * synchronizing with further updates to the page's physical 3715 * queue state. Therefore we must speculatively remove the page 3716 * from the queue now and be prepared to roll back if the queue 3717 * state update fails. If the page is not physically enqueued then 3718 * we just update its queue index. 3719 */ 3720 if ((old->flags & PGA_ENQUEUED) != 0) { 3721 new.flags &= ~PGA_ENQUEUED; 3722 next = TAILQ_NEXT(m, plinks.q); 3723 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 3724 vm_pagequeue_cnt_dec(pq); 3725 if (!vm_page_pqstate_fcmpset(m, old, new)) { 3726 if (next == NULL) 3727 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 3728 else 3729 TAILQ_INSERT_BEFORE(next, m, plinks.q); 3730 vm_pagequeue_cnt_inc(pq); 3731 return (false); 3732 } else { 3733 return (true); 3734 } 3735 } else { 3736 return (vm_page_pqstate_fcmpset(m, old, new)); 3737 } 3738 } 3739 3740 static bool 3741 vm_page_pqstate_commit_dequeue(vm_page_t m, vm_page_astate_t *old, 3742 vm_page_astate_t new) 3743 { 3744 struct vm_pagequeue *pq; 3745 vm_page_astate_t as; 3746 bool ret; 3747 3748 pq = _vm_page_pagequeue(m, old->queue); 3749 3750 /* 3751 * The queue field and PGA_ENQUEUED flag are stable only so long as the 3752 * corresponding page queue lock is held. 3753 */ 3754 vm_pagequeue_lock(pq); 3755 as = vm_page_astate_load(m); 3756 if (__predict_false(as._bits != old->_bits)) { 3757 *old = as; 3758 ret = false; 3759 } else { 3760 ret = _vm_page_pqstate_commit_dequeue(pq, m, old, new); 3761 } 3762 vm_pagequeue_unlock(pq); 3763 return (ret); 3764 } 3765 3766 /* 3767 * Commit a queue state update that enqueues or requeues a page. 3768 */ 3769 static bool 3770 _vm_page_pqstate_commit_requeue(struct vm_pagequeue *pq, vm_page_t m, 3771 vm_page_astate_t *old, vm_page_astate_t new) 3772 { 3773 struct vm_domain *vmd; 3774 3775 vm_pagequeue_assert_locked(pq); 3776 KASSERT(old->queue != PQ_NONE && new.queue == old->queue, 3777 ("%s: invalid queue indices %d %d", 3778 __func__, old->queue, new.queue)); 3779 3780 new.flags |= PGA_ENQUEUED; 3781 if (!vm_page_pqstate_fcmpset(m, old, new)) 3782 return (false); 3783 3784 if ((old->flags & PGA_ENQUEUED) != 0) 3785 TAILQ_REMOVE(&pq->pq_pl, m, plinks.q); 3786 else 3787 vm_pagequeue_cnt_inc(pq); 3788 3789 /* 3790 * Give PGA_REQUEUE_HEAD precedence over PGA_REQUEUE. In particular, if 3791 * both flags are set in close succession, only PGA_REQUEUE_HEAD will be 3792 * applied, even if it was set first. 3793 */ 3794 if ((old->flags & PGA_REQUEUE_HEAD) != 0) { 3795 vmd = vm_pagequeue_domain(m); 3796 KASSERT(pq == &vmd->vmd_pagequeues[PQ_INACTIVE], 3797 ("%s: invalid page queue for page %p", __func__, m)); 3798 TAILQ_INSERT_BEFORE(&vmd->vmd_inacthead, m, plinks.q); 3799 } else { 3800 TAILQ_INSERT_TAIL(&pq->pq_pl, m, plinks.q); 3801 } 3802 return (true); 3803 } 3804 3805 /* 3806 * Commit a queue state update that encodes a request for a deferred queue 3807 * operation. 3808 */ 3809 static bool 3810 vm_page_pqstate_commit_request(vm_page_t m, vm_page_astate_t *old, 3811 vm_page_astate_t new) 3812 { 3813 3814 KASSERT(old->queue == new.queue || new.queue != PQ_NONE, 3815 ("%s: invalid state, queue %d flags %x", 3816 __func__, new.queue, new.flags)); 3817 3818 if (old->_bits != new._bits && 3819 !vm_page_pqstate_fcmpset(m, old, new)) 3820 return (false); 3821 vm_page_pqbatch_submit(m, new.queue); 3822 return (true); 3823 } 3824 3825 /* 3826 * A generic queue state update function. This handles more cases than the 3827 * specialized functions above. 3828 */ 3829 bool 3830 vm_page_pqstate_commit(vm_page_t m, vm_page_astate_t *old, vm_page_astate_t new) 3831 { 3832 3833 if (old->_bits == new._bits) 3834 return (true); 3835 3836 if (old->queue != PQ_NONE && new.queue != old->queue) { 3837 if (!vm_page_pqstate_commit_dequeue(m, old, new)) 3838 return (false); 3839 if (new.queue != PQ_NONE) 3840 vm_page_pqbatch_submit(m, new.queue); 3841 } else { 3842 if (!vm_page_pqstate_fcmpset(m, old, new)) 3843 return (false); 3844 if (new.queue != PQ_NONE && 3845 ((new.flags & ~old->flags) & PGA_QUEUE_OP_MASK) != 0) 3846 vm_page_pqbatch_submit(m, new.queue); 3847 } 3848 return (true); 3849 } 3850 3851 /* 3852 * Apply deferred queue state updates to a page. 3853 */ 3854 static inline void 3855 vm_pqbatch_process_page(struct vm_pagequeue *pq, vm_page_t m, uint8_t queue) 3856 { 3857 vm_page_astate_t new, old; 3858 3859 CRITICAL_ASSERT(curthread); 3860 vm_pagequeue_assert_locked(pq); 3861 KASSERT(queue < PQ_COUNT, 3862 ("%s: invalid queue index %d", __func__, queue)); 3863 KASSERT(pq == _vm_page_pagequeue(m, queue), 3864 ("%s: page %p does not belong to queue %p", __func__, m, pq)); 3865 3866 for (old = vm_page_astate_load(m);;) { 3867 if (__predict_false(old.queue != queue || 3868 (old.flags & PGA_QUEUE_OP_MASK) == 0)) { 3869 counter_u64_add(queue_nops, 1); 3870 break; 3871 } 3872 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 3873 ("%s: page %p is unmanaged", __func__, m)); 3874 3875 new = old; 3876 if ((old.flags & PGA_DEQUEUE) != 0) { 3877 new.flags &= ~PGA_QUEUE_OP_MASK; 3878 new.queue = PQ_NONE; 3879 if (__predict_true(_vm_page_pqstate_commit_dequeue(pq, 3880 m, &old, new))) { 3881 counter_u64_add(queue_ops, 1); 3882 break; 3883 } 3884 } else { 3885 new.flags &= ~(PGA_REQUEUE | PGA_REQUEUE_HEAD); 3886 if (__predict_true(_vm_page_pqstate_commit_requeue(pq, 3887 m, &old, new))) { 3888 counter_u64_add(queue_ops, 1); 3889 break; 3890 } 3891 } 3892 } 3893 } 3894 3895 static void 3896 vm_pqbatch_process(struct vm_pagequeue *pq, struct vm_batchqueue *bq, 3897 uint8_t queue) 3898 { 3899 int i; 3900 3901 for (i = 0; i < bq->bq_cnt; i++) 3902 vm_pqbatch_process_page(pq, bq->bq_pa[i], queue); 3903 vm_batchqueue_init(bq); 3904 } 3905 3906 /* 3907 * vm_page_pqbatch_submit: [ internal use only ] 3908 * 3909 * Enqueue a page in the specified page queue's batched work queue. 3910 * The caller must have encoded the requested operation in the page 3911 * structure's a.flags field. 3912 */ 3913 void 3914 vm_page_pqbatch_submit(vm_page_t m, uint8_t queue) 3915 { 3916 struct vm_batchqueue *bq; 3917 struct vm_pagequeue *pq; 3918 int domain, slots_remaining; 3919 3920 KASSERT(queue < PQ_COUNT, ("invalid queue %d", queue)); 3921 3922 domain = vm_page_domain(m); 3923 critical_enter(); 3924 bq = DPCPU_PTR(pqbatch[domain][queue]); 3925 slots_remaining = vm_batchqueue_insert(bq, m); 3926 if (slots_remaining > (VM_BATCHQUEUE_SIZE >> 1)) { 3927 /* keep building the bq */ 3928 critical_exit(); 3929 return; 3930 } else if (slots_remaining > 0 ) { 3931 /* Try to process the bq if we can get the lock */ 3932 pq = &VM_DOMAIN(domain)->vmd_pagequeues[queue]; 3933 if (vm_pagequeue_trylock(pq)) { 3934 vm_pqbatch_process(pq, bq, queue); 3935 vm_pagequeue_unlock(pq); 3936 } 3937 critical_exit(); 3938 return; 3939 } 3940 critical_exit(); 3941 3942 /* if we make it here, the bq is full so wait for the lock */ 3943 3944 pq = &VM_DOMAIN(domain)->vmd_pagequeues[queue]; 3945 vm_pagequeue_lock(pq); 3946 critical_enter(); 3947 bq = DPCPU_PTR(pqbatch[domain][queue]); 3948 vm_pqbatch_process(pq, bq, queue); 3949 vm_pqbatch_process_page(pq, m, queue); 3950 vm_pagequeue_unlock(pq); 3951 critical_exit(); 3952 } 3953 3954 /* 3955 * vm_page_pqbatch_drain: [ internal use only ] 3956 * 3957 * Force all per-CPU page queue batch queues to be drained. This is 3958 * intended for use in severe memory shortages, to ensure that pages 3959 * do not remain stuck in the batch queues. 3960 */ 3961 void 3962 vm_page_pqbatch_drain(void) 3963 { 3964 struct thread *td; 3965 struct vm_domain *vmd; 3966 struct vm_pagequeue *pq; 3967 int cpu, domain, queue; 3968 3969 td = curthread; 3970 CPU_FOREACH(cpu) { 3971 thread_lock(td); 3972 sched_bind(td, cpu); 3973 thread_unlock(td); 3974 3975 for (domain = 0; domain < vm_ndomains; domain++) { 3976 vmd = VM_DOMAIN(domain); 3977 for (queue = 0; queue < PQ_COUNT; queue++) { 3978 pq = &vmd->vmd_pagequeues[queue]; 3979 vm_pagequeue_lock(pq); 3980 critical_enter(); 3981 vm_pqbatch_process(pq, 3982 DPCPU_PTR(pqbatch[domain][queue]), queue); 3983 critical_exit(); 3984 vm_pagequeue_unlock(pq); 3985 } 3986 } 3987 } 3988 thread_lock(td); 3989 sched_unbind(td); 3990 thread_unlock(td); 3991 } 3992 3993 /* 3994 * vm_page_dequeue_deferred: [ internal use only ] 3995 * 3996 * Request removal of the given page from its current page 3997 * queue. Physical removal from the queue may be deferred 3998 * indefinitely. 3999 */ 4000 void 4001 vm_page_dequeue_deferred(vm_page_t m) 4002 { 4003 vm_page_astate_t new, old; 4004 4005 old = vm_page_astate_load(m); 4006 do { 4007 if (old.queue == PQ_NONE) { 4008 KASSERT((old.flags & PGA_QUEUE_STATE_MASK) == 0, 4009 ("%s: page %p has unexpected queue state", 4010 __func__, m)); 4011 break; 4012 } 4013 new = old; 4014 new.flags |= PGA_DEQUEUE; 4015 } while (!vm_page_pqstate_commit_request(m, &old, new)); 4016 } 4017 4018 /* 4019 * vm_page_dequeue: 4020 * 4021 * Remove the page from whichever page queue it's in, if any, before 4022 * returning. 4023 */ 4024 void 4025 vm_page_dequeue(vm_page_t m) 4026 { 4027 vm_page_astate_t new, old; 4028 4029 old = vm_page_astate_load(m); 4030 do { 4031 if (old.queue == PQ_NONE) { 4032 KASSERT((old.flags & PGA_QUEUE_STATE_MASK) == 0, 4033 ("%s: page %p has unexpected queue state", 4034 __func__, m)); 4035 break; 4036 } 4037 new = old; 4038 new.flags &= ~PGA_QUEUE_OP_MASK; 4039 new.queue = PQ_NONE; 4040 } while (!vm_page_pqstate_commit_dequeue(m, &old, new)); 4041 4042 } 4043 4044 /* 4045 * Schedule the given page for insertion into the specified page queue. 4046 * Physical insertion of the page may be deferred indefinitely. 4047 */ 4048 static void 4049 vm_page_enqueue(vm_page_t m, uint8_t queue) 4050 { 4051 4052 KASSERT(m->a.queue == PQ_NONE && 4053 (m->a.flags & PGA_QUEUE_STATE_MASK) == 0, 4054 ("%s: page %p is already enqueued", __func__, m)); 4055 KASSERT(m->ref_count > 0, 4056 ("%s: page %p does not carry any references", __func__, m)); 4057 4058 m->a.queue = queue; 4059 if ((m->a.flags & PGA_REQUEUE) == 0) 4060 vm_page_aflag_set(m, PGA_REQUEUE); 4061 vm_page_pqbatch_submit(m, queue); 4062 } 4063 4064 /* 4065 * vm_page_free_prep: 4066 * 4067 * Prepares the given page to be put on the free list, 4068 * disassociating it from any VM object. The caller may return 4069 * the page to the free list only if this function returns true. 4070 * 4071 * The object, if it exists, must be locked, and then the page must 4072 * be xbusy. Otherwise the page must be not busied. A managed 4073 * page must be unmapped. 4074 */ 4075 static bool 4076 vm_page_free_prep(vm_page_t m) 4077 { 4078 4079 /* 4080 * Synchronize with threads that have dropped a reference to this 4081 * page. 4082 */ 4083 atomic_thread_fence_acq(); 4084 4085 #if defined(DIAGNOSTIC) && defined(PHYS_TO_DMAP) 4086 if (PMAP_HAS_DMAP && (m->flags & PG_ZERO) != 0) { 4087 uint64_t *p; 4088 int i; 4089 p = (uint64_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m)); 4090 for (i = 0; i < PAGE_SIZE / sizeof(uint64_t); i++, p++) 4091 KASSERT(*p == 0, ("vm_page_free_prep %p PG_ZERO %d %jx", 4092 m, i, (uintmax_t)*p)); 4093 } 4094 #endif 4095 KASSERT((m->flags & PG_NOFREE) == 0, 4096 ("%s: attempting to free a PG_NOFREE page", __func__)); 4097 if ((m->oflags & VPO_UNMANAGED) == 0) { 4098 KASSERT(!pmap_page_is_mapped(m), 4099 ("vm_page_free_prep: freeing mapped page %p", m)); 4100 KASSERT((m->a.flags & (PGA_EXECUTABLE | PGA_WRITEABLE)) == 0, 4101 ("vm_page_free_prep: mapping flags set in page %p", m)); 4102 } else { 4103 KASSERT(m->a.queue == PQ_NONE, 4104 ("vm_page_free_prep: unmanaged page %p is queued", m)); 4105 } 4106 VM_CNT_INC(v_tfree); 4107 4108 if (m->object != NULL) { 4109 KASSERT(((m->oflags & VPO_UNMANAGED) != 0) == 4110 ((m->object->flags & OBJ_UNMANAGED) != 0), 4111 ("vm_page_free_prep: managed flag mismatch for page %p", 4112 m)); 4113 vm_page_assert_xbusied(m); 4114 4115 /* 4116 * The object reference can be released without an atomic 4117 * operation. 4118 */ 4119 KASSERT((m->flags & PG_FICTITIOUS) != 0 || 4120 m->ref_count == VPRC_OBJREF, 4121 ("vm_page_free_prep: page %p has unexpected ref_count %u", 4122 m, m->ref_count)); 4123 vm_page_object_remove(m); 4124 m->ref_count -= VPRC_OBJREF; 4125 } else 4126 vm_page_assert_unbusied(m); 4127 4128 vm_page_busy_free(m); 4129 4130 /* 4131 * If fictitious remove object association and 4132 * return. 4133 */ 4134 if ((m->flags & PG_FICTITIOUS) != 0) { 4135 KASSERT(m->ref_count == 1, 4136 ("fictitious page %p is referenced", m)); 4137 KASSERT(m->a.queue == PQ_NONE, 4138 ("fictitious page %p is queued", m)); 4139 return (false); 4140 } 4141 4142 /* 4143 * Pages need not be dequeued before they are returned to the physical 4144 * memory allocator, but they must at least be marked for a deferred 4145 * dequeue. 4146 */ 4147 if ((m->oflags & VPO_UNMANAGED) == 0) 4148 vm_page_dequeue_deferred(m); 4149 4150 m->valid = 0; 4151 vm_page_undirty(m); 4152 4153 if (m->ref_count != 0) 4154 panic("vm_page_free_prep: page %p has references", m); 4155 4156 /* 4157 * Restore the default memory attribute to the page. 4158 */ 4159 if (pmap_page_get_memattr(m) != VM_MEMATTR_DEFAULT) 4160 pmap_page_set_memattr(m, VM_MEMATTR_DEFAULT); 4161 4162 #if VM_NRESERVLEVEL > 0 4163 /* 4164 * Determine whether the page belongs to a reservation. If the page was 4165 * allocated from a per-CPU cache, it cannot belong to a reservation, so 4166 * as an optimization, we avoid the check in that case. 4167 */ 4168 if ((m->flags & PG_PCPU_CACHE) == 0 && vm_reserv_free_page(m)) 4169 return (false); 4170 #endif 4171 4172 return (true); 4173 } 4174 4175 /* 4176 * vm_page_free_toq: 4177 * 4178 * Returns the given page to the free list, disassociating it 4179 * from any VM object. 4180 * 4181 * The object must be locked. The page must be exclusively busied if it 4182 * belongs to an object. 4183 */ 4184 static void 4185 vm_page_free_toq(vm_page_t m) 4186 { 4187 struct vm_domain *vmd; 4188 uma_zone_t zone; 4189 4190 if (!vm_page_free_prep(m)) 4191 return; 4192 4193 vmd = vm_pagequeue_domain(m); 4194 zone = vmd->vmd_pgcache[m->pool].zone; 4195 if ((m->flags & PG_PCPU_CACHE) != 0 && zone != NULL) { 4196 uma_zfree(zone, m); 4197 return; 4198 } 4199 vm_domain_free_lock(vmd); 4200 vm_phys_free_pages(m, 0); 4201 vm_domain_free_unlock(vmd); 4202 vm_domain_freecnt_inc(vmd, 1); 4203 } 4204 4205 /* 4206 * vm_page_free_pages_toq: 4207 * 4208 * Returns a list of pages to the free list, disassociating it 4209 * from any VM object. In other words, this is equivalent to 4210 * calling vm_page_free_toq() for each page of a list of VM objects. 4211 */ 4212 int 4213 vm_page_free_pages_toq(struct spglist *free, bool update_wire_count) 4214 { 4215 vm_page_t m; 4216 int count; 4217 4218 if (SLIST_EMPTY(free)) 4219 return (0); 4220 4221 count = 0; 4222 while ((m = SLIST_FIRST(free)) != NULL) { 4223 count++; 4224 SLIST_REMOVE_HEAD(free, plinks.s.ss); 4225 vm_page_free_toq(m); 4226 } 4227 4228 if (update_wire_count) 4229 vm_wire_sub(count); 4230 return (count); 4231 } 4232 4233 /* 4234 * Mark this page as wired down. For managed pages, this prevents reclamation 4235 * by the page daemon, or when the containing object, if any, is destroyed. 4236 */ 4237 void 4238 vm_page_wire(vm_page_t m) 4239 { 4240 u_int old; 4241 4242 #ifdef INVARIANTS 4243 if (m->object != NULL && !vm_page_busied(m) && 4244 !vm_object_busied(m->object)) 4245 VM_OBJECT_ASSERT_LOCKED(m->object); 4246 #endif 4247 KASSERT((m->flags & PG_FICTITIOUS) == 0 || 4248 VPRC_WIRE_COUNT(m->ref_count) >= 1, 4249 ("vm_page_wire: fictitious page %p has zero wirings", m)); 4250 4251 old = atomic_fetchadd_int(&m->ref_count, 1); 4252 KASSERT(VPRC_WIRE_COUNT(old) != VPRC_WIRE_COUNT_MAX, 4253 ("vm_page_wire: counter overflow for page %p", m)); 4254 if (VPRC_WIRE_COUNT(old) == 0) { 4255 if ((m->oflags & VPO_UNMANAGED) == 0) 4256 vm_page_aflag_set(m, PGA_DEQUEUE); 4257 vm_wire_add(1); 4258 } 4259 } 4260 4261 /* 4262 * Attempt to wire a mapped page following a pmap lookup of that page. 4263 * This may fail if a thread is concurrently tearing down mappings of the page. 4264 * The transient failure is acceptable because it translates to the 4265 * failure of the caller pmap_extract_and_hold(), which should be then 4266 * followed by the vm_fault() fallback, see e.g. vm_fault_quick_hold_pages(). 4267 */ 4268 bool 4269 vm_page_wire_mapped(vm_page_t m) 4270 { 4271 u_int old; 4272 4273 old = atomic_load_int(&m->ref_count); 4274 do { 4275 KASSERT(old > 0, 4276 ("vm_page_wire_mapped: wiring unreferenced page %p", m)); 4277 if ((old & VPRC_BLOCKED) != 0) 4278 return (false); 4279 } while (!atomic_fcmpset_int(&m->ref_count, &old, old + 1)); 4280 4281 if (VPRC_WIRE_COUNT(old) == 0) { 4282 if ((m->oflags & VPO_UNMANAGED) == 0) 4283 vm_page_aflag_set(m, PGA_DEQUEUE); 4284 vm_wire_add(1); 4285 } 4286 return (true); 4287 } 4288 4289 /* 4290 * Release a wiring reference to a managed page. If the page still belongs to 4291 * an object, update its position in the page queues to reflect the reference. 4292 * If the wiring was the last reference to the page, free the page. 4293 */ 4294 static void 4295 vm_page_unwire_managed(vm_page_t m, uint8_t nqueue, bool noreuse) 4296 { 4297 u_int old; 4298 4299 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 4300 ("%s: page %p is unmanaged", __func__, m)); 4301 4302 /* 4303 * Update LRU state before releasing the wiring reference. 4304 * Use a release store when updating the reference count to 4305 * synchronize with vm_page_free_prep(). 4306 */ 4307 old = atomic_load_int(&m->ref_count); 4308 do { 4309 u_int count; 4310 4311 KASSERT(VPRC_WIRE_COUNT(old) > 0, 4312 ("vm_page_unwire: wire count underflow for page %p", m)); 4313 4314 count = old & ~VPRC_BLOCKED; 4315 if (count > VPRC_OBJREF + 1) { 4316 /* 4317 * The page has at least one other wiring reference. An 4318 * earlier iteration of this loop may have called 4319 * vm_page_release_toq() and cleared PGA_DEQUEUE, so 4320 * re-set it if necessary. 4321 */ 4322 if ((vm_page_astate_load(m).flags & PGA_DEQUEUE) == 0) 4323 vm_page_aflag_set(m, PGA_DEQUEUE); 4324 } else if (count == VPRC_OBJREF + 1) { 4325 /* 4326 * This is the last wiring. Clear PGA_DEQUEUE and 4327 * update the page's queue state to reflect the 4328 * reference. If the page does not belong to an object 4329 * (i.e., the VPRC_OBJREF bit is clear), we only need to 4330 * clear leftover queue state. 4331 */ 4332 vm_page_release_toq(m, nqueue, noreuse); 4333 } else if (count == 1) { 4334 vm_page_aflag_clear(m, PGA_DEQUEUE); 4335 } 4336 } while (!atomic_fcmpset_rel_int(&m->ref_count, &old, old - 1)); 4337 4338 if (VPRC_WIRE_COUNT(old) == 1) { 4339 vm_wire_sub(1); 4340 if (old == 1) 4341 vm_page_free(m); 4342 } 4343 } 4344 4345 /* 4346 * Release one wiring of the specified page, potentially allowing it to be 4347 * paged out. 4348 * 4349 * Only managed pages belonging to an object can be paged out. If the number 4350 * of wirings transitions to zero and the page is eligible for page out, then 4351 * the page is added to the specified paging queue. If the released wiring 4352 * represented the last reference to the page, the page is freed. 4353 */ 4354 void 4355 vm_page_unwire(vm_page_t m, uint8_t nqueue) 4356 { 4357 4358 KASSERT(nqueue < PQ_COUNT, 4359 ("vm_page_unwire: invalid queue %u request for page %p", 4360 nqueue, m)); 4361 4362 if ((m->oflags & VPO_UNMANAGED) != 0) { 4363 if (vm_page_unwire_noq(m) && m->ref_count == 0) 4364 vm_page_free(m); 4365 return; 4366 } 4367 vm_page_unwire_managed(m, nqueue, false); 4368 } 4369 4370 /* 4371 * Unwire a page without (re-)inserting it into a page queue. It is up 4372 * to the caller to enqueue, requeue, or free the page as appropriate. 4373 * In most cases involving managed pages, vm_page_unwire() should be used 4374 * instead. 4375 */ 4376 bool 4377 vm_page_unwire_noq(vm_page_t m) 4378 { 4379 u_int old; 4380 4381 old = vm_page_drop(m, 1); 4382 KASSERT(VPRC_WIRE_COUNT(old) != 0, 4383 ("%s: counter underflow for page %p", __func__, m)); 4384 KASSERT((m->flags & PG_FICTITIOUS) == 0 || VPRC_WIRE_COUNT(old) > 1, 4385 ("%s: missing ref on fictitious page %p", __func__, m)); 4386 4387 if (VPRC_WIRE_COUNT(old) > 1) 4388 return (false); 4389 if ((m->oflags & VPO_UNMANAGED) == 0) 4390 vm_page_aflag_clear(m, PGA_DEQUEUE); 4391 vm_wire_sub(1); 4392 return (true); 4393 } 4394 4395 /* 4396 * Ensure that the page ends up in the specified page queue. If the page is 4397 * active or being moved to the active queue, ensure that its act_count is 4398 * at least ACT_INIT but do not otherwise mess with it. 4399 */ 4400 static __always_inline void 4401 vm_page_mvqueue(vm_page_t m, const uint8_t nqueue, const uint16_t nflag) 4402 { 4403 vm_page_astate_t old, new; 4404 4405 KASSERT(m->ref_count > 0, 4406 ("%s: page %p does not carry any references", __func__, m)); 4407 KASSERT(nflag == PGA_REQUEUE || nflag == PGA_REQUEUE_HEAD, 4408 ("%s: invalid flags %x", __func__, nflag)); 4409 4410 if ((m->oflags & VPO_UNMANAGED) != 0 || vm_page_wired(m)) 4411 return; 4412 4413 old = vm_page_astate_load(m); 4414 do { 4415 if ((old.flags & PGA_DEQUEUE) != 0) 4416 break; 4417 new = old; 4418 new.flags &= ~PGA_QUEUE_OP_MASK; 4419 if (nqueue == PQ_ACTIVE) 4420 new.act_count = max(old.act_count, ACT_INIT); 4421 if (old.queue == nqueue) { 4422 /* 4423 * There is no need to requeue pages already in the 4424 * active queue. 4425 */ 4426 if (nqueue != PQ_ACTIVE || 4427 (old.flags & PGA_ENQUEUED) == 0) 4428 new.flags |= nflag; 4429 } else { 4430 new.flags |= nflag; 4431 new.queue = nqueue; 4432 } 4433 } while (!vm_page_pqstate_commit(m, &old, new)); 4434 } 4435 4436 /* 4437 * Put the specified page on the active list (if appropriate). 4438 */ 4439 void 4440 vm_page_activate(vm_page_t m) 4441 { 4442 4443 vm_page_mvqueue(m, PQ_ACTIVE, PGA_REQUEUE); 4444 } 4445 4446 /* 4447 * Move the specified page to the tail of the inactive queue, or requeue 4448 * the page if it is already in the inactive queue. 4449 */ 4450 void 4451 vm_page_deactivate(vm_page_t m) 4452 { 4453 4454 vm_page_mvqueue(m, PQ_INACTIVE, PGA_REQUEUE); 4455 } 4456 4457 void 4458 vm_page_deactivate_noreuse(vm_page_t m) 4459 { 4460 4461 vm_page_mvqueue(m, PQ_INACTIVE, PGA_REQUEUE_HEAD); 4462 } 4463 4464 /* 4465 * Put a page in the laundry, or requeue it if it is already there. 4466 */ 4467 void 4468 vm_page_launder(vm_page_t m) 4469 { 4470 4471 vm_page_mvqueue(m, PQ_LAUNDRY, PGA_REQUEUE); 4472 } 4473 4474 /* 4475 * Put a page in the PQ_UNSWAPPABLE holding queue. 4476 */ 4477 void 4478 vm_page_unswappable(vm_page_t m) 4479 { 4480 4481 VM_OBJECT_ASSERT_LOCKED(m->object); 4482 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 4483 ("page %p already unswappable", m)); 4484 4485 vm_page_dequeue(m); 4486 vm_page_enqueue(m, PQ_UNSWAPPABLE); 4487 } 4488 4489 /* 4490 * Release a page back to the page queues in preparation for unwiring. 4491 */ 4492 static void 4493 vm_page_release_toq(vm_page_t m, uint8_t nqueue, const bool noreuse) 4494 { 4495 vm_page_astate_t old, new; 4496 uint16_t nflag; 4497 4498 /* 4499 * Use a check of the valid bits to determine whether we should 4500 * accelerate reclamation of the page. The object lock might not be 4501 * held here, in which case the check is racy. At worst we will either 4502 * accelerate reclamation of a valid page and violate LRU, or 4503 * unnecessarily defer reclamation of an invalid page. 4504 * 4505 * If we were asked to not cache the page, place it near the head of the 4506 * inactive queue so that is reclaimed sooner. 4507 */ 4508 if (noreuse || vm_page_none_valid(m)) { 4509 nqueue = PQ_INACTIVE; 4510 nflag = PGA_REQUEUE_HEAD; 4511 } else { 4512 nflag = PGA_REQUEUE; 4513 } 4514 4515 old = vm_page_astate_load(m); 4516 do { 4517 new = old; 4518 4519 /* 4520 * If the page is already in the active queue and we are not 4521 * trying to accelerate reclamation, simply mark it as 4522 * referenced and avoid any queue operations. 4523 */ 4524 new.flags &= ~PGA_QUEUE_OP_MASK; 4525 if (nflag != PGA_REQUEUE_HEAD && old.queue == PQ_ACTIVE && 4526 (old.flags & PGA_ENQUEUED) != 0) 4527 new.flags |= PGA_REFERENCED; 4528 else { 4529 new.flags |= nflag; 4530 new.queue = nqueue; 4531 } 4532 } while (!vm_page_pqstate_commit(m, &old, new)); 4533 } 4534 4535 /* 4536 * Unwire a page and either attempt to free it or re-add it to the page queues. 4537 */ 4538 void 4539 vm_page_release(vm_page_t m, int flags) 4540 { 4541 vm_object_t object; 4542 4543 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 4544 ("vm_page_release: page %p is unmanaged", m)); 4545 4546 if ((flags & VPR_TRYFREE) != 0) { 4547 for (;;) { 4548 object = atomic_load_ptr(&m->object); 4549 if (object == NULL) 4550 break; 4551 /* Depends on type-stability. */ 4552 if (vm_page_busied(m) || !VM_OBJECT_TRYWLOCK(object)) 4553 break; 4554 if (object == m->object) { 4555 vm_page_release_locked(m, flags); 4556 VM_OBJECT_WUNLOCK(object); 4557 return; 4558 } 4559 VM_OBJECT_WUNLOCK(object); 4560 } 4561 } 4562 vm_page_unwire_managed(m, PQ_INACTIVE, flags != 0); 4563 } 4564 4565 /* See vm_page_release(). */ 4566 void 4567 vm_page_release_locked(vm_page_t m, int flags) 4568 { 4569 4570 VM_OBJECT_ASSERT_WLOCKED(m->object); 4571 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 4572 ("vm_page_release_locked: page %p is unmanaged", m)); 4573 4574 if (vm_page_unwire_noq(m)) { 4575 if ((flags & VPR_TRYFREE) != 0 && 4576 (m->object->ref_count == 0 || !pmap_page_is_mapped(m)) && 4577 m->dirty == 0 && vm_page_tryxbusy(m)) { 4578 /* 4579 * An unlocked lookup may have wired the page before the 4580 * busy lock was acquired, in which case the page must 4581 * not be freed. 4582 */ 4583 if (__predict_true(!vm_page_wired(m))) { 4584 vm_page_free(m); 4585 return; 4586 } 4587 vm_page_xunbusy(m); 4588 } else { 4589 vm_page_release_toq(m, PQ_INACTIVE, flags != 0); 4590 } 4591 } 4592 } 4593 4594 static bool 4595 vm_page_try_blocked_op(vm_page_t m, void (*op)(vm_page_t)) 4596 { 4597 u_int old; 4598 4599 KASSERT(m->object != NULL && (m->oflags & VPO_UNMANAGED) == 0, 4600 ("vm_page_try_blocked_op: page %p has no object", m)); 4601 KASSERT(vm_page_busied(m), 4602 ("vm_page_try_blocked_op: page %p is not busy", m)); 4603 VM_OBJECT_ASSERT_LOCKED(m->object); 4604 4605 old = atomic_load_int(&m->ref_count); 4606 do { 4607 KASSERT(old != 0, 4608 ("vm_page_try_blocked_op: page %p has no references", m)); 4609 KASSERT((old & VPRC_BLOCKED) == 0, 4610 ("vm_page_try_blocked_op: page %p blocks wirings", m)); 4611 if (VPRC_WIRE_COUNT(old) != 0) 4612 return (false); 4613 } while (!atomic_fcmpset_int(&m->ref_count, &old, old | VPRC_BLOCKED)); 4614 4615 (op)(m); 4616 4617 /* 4618 * If the object is read-locked, new wirings may be created via an 4619 * object lookup. 4620 */ 4621 old = vm_page_drop(m, VPRC_BLOCKED); 4622 KASSERT(!VM_OBJECT_WOWNED(m->object) || 4623 old == (VPRC_BLOCKED | VPRC_OBJREF), 4624 ("vm_page_try_blocked_op: unexpected refcount value %u for %p", 4625 old, m)); 4626 return (true); 4627 } 4628 4629 /* 4630 * Atomically check for wirings and remove all mappings of the page. 4631 */ 4632 bool 4633 vm_page_try_remove_all(vm_page_t m) 4634 { 4635 4636 return (vm_page_try_blocked_op(m, pmap_remove_all)); 4637 } 4638 4639 /* 4640 * Atomically check for wirings and remove all writeable mappings of the page. 4641 */ 4642 bool 4643 vm_page_try_remove_write(vm_page_t m) 4644 { 4645 4646 return (vm_page_try_blocked_op(m, pmap_remove_write)); 4647 } 4648 4649 /* 4650 * vm_page_advise 4651 * 4652 * Apply the specified advice to the given page. 4653 */ 4654 void 4655 vm_page_advise(vm_page_t m, int advice) 4656 { 4657 4658 VM_OBJECT_ASSERT_WLOCKED(m->object); 4659 vm_page_assert_xbusied(m); 4660 4661 if (advice == MADV_FREE) 4662 /* 4663 * Mark the page clean. This will allow the page to be freed 4664 * without first paging it out. MADV_FREE pages are often 4665 * quickly reused by malloc(3), so we do not do anything that 4666 * would result in a page fault on a later access. 4667 */ 4668 vm_page_undirty(m); 4669 else if (advice != MADV_DONTNEED) { 4670 if (advice == MADV_WILLNEED) 4671 vm_page_activate(m); 4672 return; 4673 } 4674 4675 if (advice != MADV_FREE && m->dirty == 0 && pmap_is_modified(m)) 4676 vm_page_dirty(m); 4677 4678 /* 4679 * Clear any references to the page. Otherwise, the page daemon will 4680 * immediately reactivate the page. 4681 */ 4682 vm_page_aflag_clear(m, PGA_REFERENCED); 4683 4684 /* 4685 * Place clean pages near the head of the inactive queue rather than 4686 * the tail, thus defeating the queue's LRU operation and ensuring that 4687 * the page will be reused quickly. Dirty pages not already in the 4688 * laundry are moved there. 4689 */ 4690 if (m->dirty == 0) 4691 vm_page_deactivate_noreuse(m); 4692 else if (!vm_page_in_laundry(m)) 4693 vm_page_launder(m); 4694 } 4695 4696 /* 4697 * vm_page_grab_release 4698 * 4699 * Helper routine for grab functions to release busy on return. 4700 */ 4701 static inline void 4702 vm_page_grab_release(vm_page_t m, int allocflags) 4703 { 4704 4705 if ((allocflags & VM_ALLOC_NOBUSY) != 0) { 4706 if ((allocflags & VM_ALLOC_IGN_SBUSY) != 0) 4707 vm_page_sunbusy(m); 4708 else 4709 vm_page_xunbusy(m); 4710 } 4711 } 4712 4713 /* 4714 * vm_page_grab_sleep 4715 * 4716 * Sleep for busy according to VM_ALLOC_ parameters. Returns true 4717 * if the caller should retry and false otherwise. 4718 * 4719 * If the object is locked on entry the object will be unlocked with 4720 * false returns and still locked but possibly having been dropped 4721 * with true returns. 4722 */ 4723 static bool 4724 vm_page_grab_sleep(vm_object_t object, vm_page_t m, vm_pindex_t pindex, 4725 const char *wmesg, int allocflags, bool locked) 4726 { 4727 4728 if ((allocflags & VM_ALLOC_NOWAIT) != 0) 4729 return (false); 4730 4731 /* 4732 * Reference the page before unlocking and sleeping so that 4733 * the page daemon is less likely to reclaim it. 4734 */ 4735 if (locked && (allocflags & VM_ALLOC_NOCREAT) == 0) 4736 vm_page_reference(m); 4737 4738 if (_vm_page_busy_sleep(object, m, pindex, wmesg, allocflags, locked) && 4739 locked) 4740 VM_OBJECT_WLOCK(object); 4741 if ((allocflags & VM_ALLOC_WAITFAIL) != 0) 4742 return (false); 4743 4744 return (true); 4745 } 4746 4747 /* 4748 * Assert that the grab flags are valid. 4749 */ 4750 static inline void 4751 vm_page_grab_check(int allocflags) 4752 { 4753 4754 KASSERT((allocflags & VM_ALLOC_NOBUSY) == 0 || 4755 (allocflags & VM_ALLOC_WIRED) != 0, 4756 ("vm_page_grab*: the pages must be busied or wired")); 4757 4758 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || 4759 (allocflags & VM_ALLOC_IGN_SBUSY) != 0, 4760 ("vm_page_grab*: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch")); 4761 } 4762 4763 /* 4764 * Calculate the page allocation flags for grab. 4765 */ 4766 static inline int 4767 vm_page_grab_pflags(int allocflags) 4768 { 4769 int pflags; 4770 4771 pflags = allocflags & 4772 ~(VM_ALLOC_NOWAIT | VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL | 4773 VM_ALLOC_NOBUSY | VM_ALLOC_IGN_SBUSY); 4774 if ((allocflags & VM_ALLOC_NOWAIT) == 0) 4775 pflags |= VM_ALLOC_WAITFAIL; 4776 if ((allocflags & VM_ALLOC_IGN_SBUSY) != 0) 4777 pflags |= VM_ALLOC_SBUSY; 4778 4779 return (pflags); 4780 } 4781 4782 /* 4783 * Grab a page, waiting until we are waken up due to the page 4784 * changing state. We keep on waiting, if the page continues 4785 * to be in the object. If the page doesn't exist, first allocate it 4786 * and then conditionally zero it. 4787 * 4788 * This routine may sleep. 4789 * 4790 * The object must be locked on entry. The lock will, however, be released 4791 * and reacquired if the routine sleeps. 4792 */ 4793 vm_page_t 4794 vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags) 4795 { 4796 vm_page_t m; 4797 4798 VM_OBJECT_ASSERT_WLOCKED(object); 4799 vm_page_grab_check(allocflags); 4800 4801 retrylookup: 4802 if ((m = vm_page_lookup(object, pindex)) != NULL) { 4803 if (!vm_page_tryacquire(m, allocflags)) { 4804 if (vm_page_grab_sleep(object, m, pindex, "pgrbwt", 4805 allocflags, true)) 4806 goto retrylookup; 4807 return (NULL); 4808 } 4809 goto out; 4810 } 4811 if ((allocflags & VM_ALLOC_NOCREAT) != 0) 4812 return (NULL); 4813 m = vm_page_alloc(object, pindex, vm_page_grab_pflags(allocflags)); 4814 if (m == NULL) { 4815 if ((allocflags & (VM_ALLOC_NOWAIT | VM_ALLOC_WAITFAIL)) != 0) 4816 return (NULL); 4817 goto retrylookup; 4818 } 4819 if (allocflags & VM_ALLOC_ZERO && (m->flags & PG_ZERO) == 0) 4820 pmap_zero_page(m); 4821 4822 out: 4823 vm_page_grab_release(m, allocflags); 4824 4825 return (m); 4826 } 4827 4828 /* 4829 * Attempt to validate a page, locklessly acquiring it if necessary, given a 4830 * (object, pindex) tuple and either an invalided page or NULL. The resulting 4831 * page will be validated against the identity tuple, and busied or wired as 4832 * requested. A NULL page returned guarantees that the page was not in radix at 4833 * the time of the call but callers must perform higher level synchronization or 4834 * retry the operation under a lock if they require an atomic answer. This is 4835 * the only lock free validation routine, other routines can depend on the 4836 * resulting page state. 4837 * 4838 * The return value PAGE_NOT_ACQUIRED indicates that the operation failed due to 4839 * caller flags. 4840 */ 4841 #define PAGE_NOT_ACQUIRED ((vm_page_t)1) 4842 static vm_page_t 4843 vm_page_acquire_unlocked(vm_object_t object, vm_pindex_t pindex, vm_page_t m, 4844 int allocflags) 4845 { 4846 if (m == NULL) 4847 m = vm_page_lookup_unlocked(object, pindex); 4848 for (; m != NULL; m = vm_page_lookup_unlocked(object, pindex)) { 4849 if (vm_page_trybusy(m, allocflags)) { 4850 if (m->object == object && m->pindex == pindex) { 4851 if ((allocflags & VM_ALLOC_WIRED) != 0) 4852 vm_page_wire(m); 4853 vm_page_grab_release(m, allocflags); 4854 break; 4855 } 4856 /* relookup. */ 4857 vm_page_busy_release(m); 4858 cpu_spinwait(); 4859 continue; 4860 } 4861 if (!vm_page_grab_sleep(object, m, pindex, "pgnslp", 4862 allocflags, false)) 4863 return (PAGE_NOT_ACQUIRED); 4864 } 4865 return (m); 4866 } 4867 4868 /* 4869 * Try to locklessly grab a page and fall back to the object lock if NOCREAT 4870 * is not set. 4871 */ 4872 vm_page_t 4873 vm_page_grab_unlocked(vm_object_t object, vm_pindex_t pindex, int allocflags) 4874 { 4875 vm_page_t m; 4876 4877 vm_page_grab_check(allocflags); 4878 m = vm_page_acquire_unlocked(object, pindex, NULL, allocflags); 4879 if (m == PAGE_NOT_ACQUIRED) 4880 return (NULL); 4881 if (m != NULL) 4882 return (m); 4883 4884 /* 4885 * The radix lockless lookup should never return a false negative 4886 * errors. If the user specifies NOCREAT they are guaranteed there 4887 * was no page present at the instant of the call. A NOCREAT caller 4888 * must handle create races gracefully. 4889 */ 4890 if ((allocflags & VM_ALLOC_NOCREAT) != 0) 4891 return (NULL); 4892 4893 VM_OBJECT_WLOCK(object); 4894 m = vm_page_grab(object, pindex, allocflags); 4895 VM_OBJECT_WUNLOCK(object); 4896 4897 return (m); 4898 } 4899 4900 /* 4901 * Grab a page and make it valid, paging in if necessary. Pages missing from 4902 * their pager are zero filled and validated. If a VM_ALLOC_COUNT is supplied 4903 * and the page is not valid as many as VM_INITIAL_PAGEIN pages can be brought 4904 * in simultaneously. Additional pages will be left on a paging queue but 4905 * will neither be wired nor busy regardless of allocflags. 4906 */ 4907 int 4908 vm_page_grab_valid(vm_page_t *mp, vm_object_t object, vm_pindex_t pindex, int allocflags) 4909 { 4910 vm_page_t m; 4911 vm_page_t ma[VM_INITIAL_PAGEIN]; 4912 int after, i, pflags, rv; 4913 4914 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || 4915 (allocflags & VM_ALLOC_IGN_SBUSY) != 0, 4916 ("vm_page_grab_valid: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY mismatch")); 4917 KASSERT((allocflags & 4918 (VM_ALLOC_NOWAIT | VM_ALLOC_WAITFAIL | VM_ALLOC_ZERO)) == 0, 4919 ("vm_page_grab_valid: Invalid flags 0x%X", allocflags)); 4920 VM_OBJECT_ASSERT_WLOCKED(object); 4921 pflags = allocflags & ~(VM_ALLOC_NOBUSY | VM_ALLOC_SBUSY | 4922 VM_ALLOC_WIRED | VM_ALLOC_IGN_SBUSY); 4923 pflags |= VM_ALLOC_WAITFAIL; 4924 4925 retrylookup: 4926 if ((m = vm_page_lookup(object, pindex)) != NULL) { 4927 /* 4928 * If the page is fully valid it can only become invalid 4929 * with the object lock held. If it is not valid it can 4930 * become valid with the busy lock held. Therefore, we 4931 * may unnecessarily lock the exclusive busy here if we 4932 * race with I/O completion not using the object lock. 4933 * However, we will not end up with an invalid page and a 4934 * shared lock. 4935 */ 4936 if (!vm_page_trybusy(m, 4937 vm_page_all_valid(m) ? allocflags : 0)) { 4938 (void)vm_page_grab_sleep(object, m, pindex, "pgrbwt", 4939 allocflags, true); 4940 goto retrylookup; 4941 } 4942 if (vm_page_all_valid(m)) 4943 goto out; 4944 if ((allocflags & VM_ALLOC_NOCREAT) != 0) { 4945 vm_page_busy_release(m); 4946 *mp = NULL; 4947 return (VM_PAGER_FAIL); 4948 } 4949 } else if ((allocflags & VM_ALLOC_NOCREAT) != 0) { 4950 *mp = NULL; 4951 return (VM_PAGER_FAIL); 4952 } else if ((m = vm_page_alloc(object, pindex, pflags)) == NULL) { 4953 if (!vm_pager_can_alloc_page(object, pindex)) { 4954 *mp = NULL; 4955 return (VM_PAGER_AGAIN); 4956 } 4957 goto retrylookup; 4958 } 4959 4960 vm_page_assert_xbusied(m); 4961 if (vm_pager_has_page(object, pindex, NULL, &after)) { 4962 after = MIN(after, VM_INITIAL_PAGEIN); 4963 after = MIN(after, allocflags >> VM_ALLOC_COUNT_SHIFT); 4964 after = MAX(after, 1); 4965 ma[0] = m; 4966 for (i = 1; i < after; i++) { 4967 if ((ma[i] = vm_page_next(ma[i - 1])) != NULL) { 4968 if (vm_page_any_valid(ma[i]) || 4969 !vm_page_tryxbusy(ma[i])) 4970 break; 4971 } else { 4972 ma[i] = vm_page_alloc(object, m->pindex + i, 4973 VM_ALLOC_NORMAL); 4974 if (ma[i] == NULL) 4975 break; 4976 } 4977 } 4978 after = i; 4979 vm_object_pip_add(object, after); 4980 VM_OBJECT_WUNLOCK(object); 4981 rv = vm_pager_get_pages(object, ma, after, NULL, NULL); 4982 VM_OBJECT_WLOCK(object); 4983 vm_object_pip_wakeupn(object, after); 4984 /* Pager may have replaced a page. */ 4985 m = ma[0]; 4986 if (rv != VM_PAGER_OK) { 4987 for (i = 0; i < after; i++) { 4988 if (!vm_page_wired(ma[i])) 4989 vm_page_free(ma[i]); 4990 else 4991 vm_page_xunbusy(ma[i]); 4992 } 4993 *mp = NULL; 4994 return (rv); 4995 } 4996 for (i = 1; i < after; i++) 4997 vm_page_readahead_finish(ma[i]); 4998 MPASS(vm_page_all_valid(m)); 4999 } else { 5000 vm_page_zero_invalid(m, TRUE); 5001 } 5002 out: 5003 if ((allocflags & VM_ALLOC_WIRED) != 0) 5004 vm_page_wire(m); 5005 if ((allocflags & VM_ALLOC_SBUSY) != 0 && vm_page_xbusied(m)) 5006 vm_page_busy_downgrade(m); 5007 else if ((allocflags & VM_ALLOC_NOBUSY) != 0) 5008 vm_page_busy_release(m); 5009 *mp = m; 5010 return (VM_PAGER_OK); 5011 } 5012 5013 /* 5014 * Locklessly grab a valid page. If the page is not valid or not yet 5015 * allocated this will fall back to the object lock method. 5016 */ 5017 int 5018 vm_page_grab_valid_unlocked(vm_page_t *mp, vm_object_t object, 5019 vm_pindex_t pindex, int allocflags) 5020 { 5021 vm_page_t m; 5022 int flags; 5023 int error; 5024 5025 KASSERT((allocflags & VM_ALLOC_SBUSY) == 0 || 5026 (allocflags & VM_ALLOC_IGN_SBUSY) != 0, 5027 ("vm_page_grab_valid_unlocked: VM_ALLOC_SBUSY/VM_ALLOC_IGN_SBUSY " 5028 "mismatch")); 5029 KASSERT((allocflags & 5030 (VM_ALLOC_NOWAIT | VM_ALLOC_WAITFAIL | VM_ALLOC_ZERO)) == 0, 5031 ("vm_page_grab_valid_unlocked: Invalid flags 0x%X", allocflags)); 5032 5033 /* 5034 * Attempt a lockless lookup and busy. We need at least an sbusy 5035 * before we can inspect the valid field and return a wired page. 5036 */ 5037 flags = allocflags & ~(VM_ALLOC_NOBUSY | VM_ALLOC_WIRED); 5038 vm_page_grab_check(flags); 5039 m = vm_page_acquire_unlocked(object, pindex, NULL, flags); 5040 if (m == PAGE_NOT_ACQUIRED) 5041 return (VM_PAGER_FAIL); 5042 if (m != NULL) { 5043 if (vm_page_all_valid(m)) { 5044 if ((allocflags & VM_ALLOC_WIRED) != 0) 5045 vm_page_wire(m); 5046 vm_page_grab_release(m, allocflags); 5047 *mp = m; 5048 return (VM_PAGER_OK); 5049 } 5050 vm_page_busy_release(m); 5051 } 5052 if ((allocflags & VM_ALLOC_NOCREAT) != 0) { 5053 *mp = NULL; 5054 return (VM_PAGER_FAIL); 5055 } 5056 VM_OBJECT_WLOCK(object); 5057 error = vm_page_grab_valid(mp, object, pindex, allocflags); 5058 VM_OBJECT_WUNLOCK(object); 5059 5060 return (error); 5061 } 5062 5063 /* 5064 * Return the specified range of pages from the given object. For each 5065 * page offset within the range, if a page already exists within the object 5066 * at that offset and it is busy, then wait for it to change state. If, 5067 * instead, the page doesn't exist, then allocate it. 5068 * 5069 * The caller must always specify an allocation class. 5070 * 5071 * allocation classes: 5072 * VM_ALLOC_NORMAL normal process request 5073 * VM_ALLOC_SYSTEM system *really* needs the pages 5074 * 5075 * The caller must always specify that the pages are to be busied and/or 5076 * wired. 5077 * 5078 * optional allocation flags: 5079 * VM_ALLOC_IGN_SBUSY do not sleep on soft busy pages 5080 * VM_ALLOC_NOBUSY do not exclusive busy the page 5081 * VM_ALLOC_NOWAIT do not sleep 5082 * VM_ALLOC_SBUSY set page to sbusy state 5083 * VM_ALLOC_WIRED wire the pages 5084 * VM_ALLOC_ZERO zero and validate any invalid pages 5085 * 5086 * If VM_ALLOC_NOWAIT is not specified, this routine may sleep. Otherwise, it 5087 * may return a partial prefix of the requested range. 5088 */ 5089 int 5090 vm_page_grab_pages(vm_object_t object, vm_pindex_t pindex, int allocflags, 5091 vm_page_t *ma, int count) 5092 { 5093 vm_page_t m, mpred; 5094 int pflags; 5095 int i; 5096 5097 VM_OBJECT_ASSERT_WLOCKED(object); 5098 KASSERT(((u_int)allocflags >> VM_ALLOC_COUNT_SHIFT) == 0, 5099 ("vm_page_grap_pages: VM_ALLOC_COUNT() is not allowed")); 5100 KASSERT(count > 0, 5101 ("vm_page_grab_pages: invalid page count %d", count)); 5102 vm_page_grab_check(allocflags); 5103 5104 pflags = vm_page_grab_pflags(allocflags); 5105 i = 0; 5106 retrylookup: 5107 m = vm_page_mpred(object, pindex + i); 5108 if (m == NULL || m->pindex != pindex + i) { 5109 mpred = m; 5110 m = NULL; 5111 } else 5112 mpred = TAILQ_PREV(m, pglist, listq); 5113 for (; i < count; i++) { 5114 if (m != NULL) { 5115 if (!vm_page_tryacquire(m, allocflags)) { 5116 if (vm_page_grab_sleep(object, m, pindex + i, 5117 "grbmaw", allocflags, true)) 5118 goto retrylookup; 5119 break; 5120 } 5121 } else { 5122 if ((allocflags & VM_ALLOC_NOCREAT) != 0) 5123 break; 5124 m = vm_page_alloc_after(object, pindex + i, 5125 pflags | VM_ALLOC_COUNT(count - i), mpred); 5126 if (m == NULL) { 5127 if ((allocflags & (VM_ALLOC_NOWAIT | 5128 VM_ALLOC_WAITFAIL)) != 0) 5129 break; 5130 goto retrylookup; 5131 } 5132 } 5133 if (vm_page_none_valid(m) && 5134 (allocflags & VM_ALLOC_ZERO) != 0) { 5135 if ((m->flags & PG_ZERO) == 0) 5136 pmap_zero_page(m); 5137 vm_page_valid(m); 5138 } 5139 vm_page_grab_release(m, allocflags); 5140 ma[i] = mpred = m; 5141 m = vm_page_next(m); 5142 } 5143 return (i); 5144 } 5145 5146 /* 5147 * Unlocked variant of vm_page_grab_pages(). This accepts the same flags 5148 * and will fall back to the locked variant to handle allocation. 5149 */ 5150 int 5151 vm_page_grab_pages_unlocked(vm_object_t object, vm_pindex_t pindex, 5152 int allocflags, vm_page_t *ma, int count) 5153 { 5154 vm_page_t m; 5155 int flags; 5156 int i; 5157 5158 KASSERT(count > 0, 5159 ("vm_page_grab_pages_unlocked: invalid page count %d", count)); 5160 vm_page_grab_check(allocflags); 5161 5162 /* 5163 * Modify flags for lockless acquire to hold the page until we 5164 * set it valid if necessary. 5165 */ 5166 flags = allocflags & ~VM_ALLOC_NOBUSY; 5167 vm_page_grab_check(flags); 5168 m = NULL; 5169 for (i = 0; i < count; i++, pindex++) { 5170 /* 5171 * We may see a false NULL here because the previous page has 5172 * been removed or just inserted and the list is loaded without 5173 * barriers. Switch to radix to verify. 5174 */ 5175 if (m == NULL || QMD_IS_TRASHED(m) || m->pindex != pindex || 5176 atomic_load_ptr(&m->object) != object) { 5177 /* 5178 * This guarantees the result is instantaneously 5179 * correct. 5180 */ 5181 m = NULL; 5182 } 5183 m = vm_page_acquire_unlocked(object, pindex, m, flags); 5184 if (m == PAGE_NOT_ACQUIRED) 5185 return (i); 5186 if (m == NULL) 5187 break; 5188 if ((flags & VM_ALLOC_ZERO) != 0 && vm_page_none_valid(m)) { 5189 if ((m->flags & PG_ZERO) == 0) 5190 pmap_zero_page(m); 5191 vm_page_valid(m); 5192 } 5193 /* m will still be wired or busy according to flags. */ 5194 vm_page_grab_release(m, allocflags); 5195 ma[i] = m; 5196 m = TAILQ_NEXT(m, listq); 5197 } 5198 if (i == count || (allocflags & VM_ALLOC_NOCREAT) != 0) 5199 return (i); 5200 count -= i; 5201 VM_OBJECT_WLOCK(object); 5202 i += vm_page_grab_pages(object, pindex, allocflags, &ma[i], count); 5203 VM_OBJECT_WUNLOCK(object); 5204 5205 return (i); 5206 } 5207 5208 /* 5209 * Mapping function for valid or dirty bits in a page. 5210 * 5211 * Inputs are required to range within a page. 5212 */ 5213 vm_page_bits_t 5214 vm_page_bits(int base, int size) 5215 { 5216 int first_bit; 5217 int last_bit; 5218 5219 KASSERT( 5220 base + size <= PAGE_SIZE, 5221 ("vm_page_bits: illegal base/size %d/%d", base, size) 5222 ); 5223 5224 if (size == 0) /* handle degenerate case */ 5225 return (0); 5226 5227 first_bit = base >> DEV_BSHIFT; 5228 last_bit = (base + size - 1) >> DEV_BSHIFT; 5229 5230 return (((vm_page_bits_t)2 << last_bit) - 5231 ((vm_page_bits_t)1 << first_bit)); 5232 } 5233 5234 void 5235 vm_page_bits_set(vm_page_t m, vm_page_bits_t *bits, vm_page_bits_t set) 5236 { 5237 5238 #if PAGE_SIZE == 32768 5239 atomic_set_64((uint64_t *)bits, set); 5240 #elif PAGE_SIZE == 16384 5241 atomic_set_32((uint32_t *)bits, set); 5242 #elif (PAGE_SIZE == 8192) && defined(atomic_set_16) 5243 atomic_set_16((uint16_t *)bits, set); 5244 #elif (PAGE_SIZE == 4096) && defined(atomic_set_8) 5245 atomic_set_8((uint8_t *)bits, set); 5246 #else /* PAGE_SIZE <= 8192 */ 5247 uintptr_t addr; 5248 int shift; 5249 5250 addr = (uintptr_t)bits; 5251 /* 5252 * Use a trick to perform a 32-bit atomic on the 5253 * containing aligned word, to not depend on the existence 5254 * of atomic_{set, clear}_{8, 16}. 5255 */ 5256 shift = addr & (sizeof(uint32_t) - 1); 5257 #if BYTE_ORDER == BIG_ENDIAN 5258 shift = (sizeof(uint32_t) - sizeof(vm_page_bits_t) - shift) * NBBY; 5259 #else 5260 shift *= NBBY; 5261 #endif 5262 addr &= ~(sizeof(uint32_t) - 1); 5263 atomic_set_32((uint32_t *)addr, set << shift); 5264 #endif /* PAGE_SIZE */ 5265 } 5266 5267 static inline void 5268 vm_page_bits_clear(vm_page_t m, vm_page_bits_t *bits, vm_page_bits_t clear) 5269 { 5270 5271 #if PAGE_SIZE == 32768 5272 atomic_clear_64((uint64_t *)bits, clear); 5273 #elif PAGE_SIZE == 16384 5274 atomic_clear_32((uint32_t *)bits, clear); 5275 #elif (PAGE_SIZE == 8192) && defined(atomic_clear_16) 5276 atomic_clear_16((uint16_t *)bits, clear); 5277 #elif (PAGE_SIZE == 4096) && defined(atomic_clear_8) 5278 atomic_clear_8((uint8_t *)bits, clear); 5279 #else /* PAGE_SIZE <= 8192 */ 5280 uintptr_t addr; 5281 int shift; 5282 5283 addr = (uintptr_t)bits; 5284 /* 5285 * Use a trick to perform a 32-bit atomic on the 5286 * containing aligned word, to not depend on the existence 5287 * of atomic_{set, clear}_{8, 16}. 5288 */ 5289 shift = addr & (sizeof(uint32_t) - 1); 5290 #if BYTE_ORDER == BIG_ENDIAN 5291 shift = (sizeof(uint32_t) - sizeof(vm_page_bits_t) - shift) * NBBY; 5292 #else 5293 shift *= NBBY; 5294 #endif 5295 addr &= ~(sizeof(uint32_t) - 1); 5296 atomic_clear_32((uint32_t *)addr, clear << shift); 5297 #endif /* PAGE_SIZE */ 5298 } 5299 5300 static inline vm_page_bits_t 5301 vm_page_bits_swap(vm_page_t m, vm_page_bits_t *bits, vm_page_bits_t newbits) 5302 { 5303 #if PAGE_SIZE == 32768 5304 uint64_t old; 5305 5306 old = *bits; 5307 while (atomic_fcmpset_64(bits, &old, newbits) == 0); 5308 return (old); 5309 #elif PAGE_SIZE == 16384 5310 uint32_t old; 5311 5312 old = *bits; 5313 while (atomic_fcmpset_32(bits, &old, newbits) == 0); 5314 return (old); 5315 #elif (PAGE_SIZE == 8192) && defined(atomic_fcmpset_16) 5316 uint16_t old; 5317 5318 old = *bits; 5319 while (atomic_fcmpset_16(bits, &old, newbits) == 0); 5320 return (old); 5321 #elif (PAGE_SIZE == 4096) && defined(atomic_fcmpset_8) 5322 uint8_t old; 5323 5324 old = *bits; 5325 while (atomic_fcmpset_8(bits, &old, newbits) == 0); 5326 return (old); 5327 #else /* PAGE_SIZE <= 4096*/ 5328 uintptr_t addr; 5329 uint32_t old, new, mask; 5330 int shift; 5331 5332 addr = (uintptr_t)bits; 5333 /* 5334 * Use a trick to perform a 32-bit atomic on the 5335 * containing aligned word, to not depend on the existence 5336 * of atomic_{set, swap, clear}_{8, 16}. 5337 */ 5338 shift = addr & (sizeof(uint32_t) - 1); 5339 #if BYTE_ORDER == BIG_ENDIAN 5340 shift = (sizeof(uint32_t) - sizeof(vm_page_bits_t) - shift) * NBBY; 5341 #else 5342 shift *= NBBY; 5343 #endif 5344 addr &= ~(sizeof(uint32_t) - 1); 5345 mask = VM_PAGE_BITS_ALL << shift; 5346 5347 old = *bits; 5348 do { 5349 new = old & ~mask; 5350 new |= newbits << shift; 5351 } while (atomic_fcmpset_32((uint32_t *)addr, &old, new) == 0); 5352 return (old >> shift); 5353 #endif /* PAGE_SIZE */ 5354 } 5355 5356 /* 5357 * vm_page_set_valid_range: 5358 * 5359 * Sets portions of a page valid. The arguments are expected 5360 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive 5361 * of any partial chunks touched by the range. The invalid portion of 5362 * such chunks will be zeroed. 5363 * 5364 * (base + size) must be less then or equal to PAGE_SIZE. 5365 */ 5366 void 5367 vm_page_set_valid_range(vm_page_t m, int base, int size) 5368 { 5369 int endoff, frag; 5370 vm_page_bits_t pagebits; 5371 5372 vm_page_assert_busied(m); 5373 if (size == 0) /* handle degenerate case */ 5374 return; 5375 5376 /* 5377 * If the base is not DEV_BSIZE aligned and the valid 5378 * bit is clear, we have to zero out a portion of the 5379 * first block. 5380 */ 5381 if ((frag = rounddown2(base, DEV_BSIZE)) != base && 5382 (m->valid & (1 << (base >> DEV_BSHIFT))) == 0) 5383 pmap_zero_page_area(m, frag, base - frag); 5384 5385 /* 5386 * If the ending offset is not DEV_BSIZE aligned and the 5387 * valid bit is clear, we have to zero out a portion of 5388 * the last block. 5389 */ 5390 endoff = base + size; 5391 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && 5392 (m->valid & (1 << (endoff >> DEV_BSHIFT))) == 0) 5393 pmap_zero_page_area(m, endoff, 5394 DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); 5395 5396 /* 5397 * Assert that no previously invalid block that is now being validated 5398 * is already dirty. 5399 */ 5400 KASSERT((~m->valid & vm_page_bits(base, size) & m->dirty) == 0, 5401 ("vm_page_set_valid_range: page %p is dirty", m)); 5402 5403 /* 5404 * Set valid bits inclusive of any overlap. 5405 */ 5406 pagebits = vm_page_bits(base, size); 5407 if (vm_page_xbusied(m)) 5408 m->valid |= pagebits; 5409 else 5410 vm_page_bits_set(m, &m->valid, pagebits); 5411 } 5412 5413 /* 5414 * Set the page dirty bits and free the invalid swap space if 5415 * present. Returns the previous dirty bits. 5416 */ 5417 vm_page_bits_t 5418 vm_page_set_dirty(vm_page_t m) 5419 { 5420 vm_page_bits_t old; 5421 5422 VM_PAGE_OBJECT_BUSY_ASSERT(m); 5423 5424 if (vm_page_xbusied(m) && !pmap_page_is_write_mapped(m)) { 5425 old = m->dirty; 5426 m->dirty = VM_PAGE_BITS_ALL; 5427 } else 5428 old = vm_page_bits_swap(m, &m->dirty, VM_PAGE_BITS_ALL); 5429 if (old == 0 && (m->a.flags & PGA_SWAP_SPACE) != 0) 5430 vm_pager_page_unswapped(m); 5431 5432 return (old); 5433 } 5434 5435 /* 5436 * Clear the given bits from the specified page's dirty field. 5437 */ 5438 static __inline void 5439 vm_page_clear_dirty_mask(vm_page_t m, vm_page_bits_t pagebits) 5440 { 5441 5442 vm_page_assert_busied(m); 5443 5444 /* 5445 * If the page is xbusied and not write mapped we are the 5446 * only thread that can modify dirty bits. Otherwise, The pmap 5447 * layer can call vm_page_dirty() without holding a distinguished 5448 * lock. The combination of page busy and atomic operations 5449 * suffice to guarantee consistency of the page dirty field. 5450 */ 5451 if (vm_page_xbusied(m) && !pmap_page_is_write_mapped(m)) 5452 m->dirty &= ~pagebits; 5453 else 5454 vm_page_bits_clear(m, &m->dirty, pagebits); 5455 } 5456 5457 /* 5458 * vm_page_set_validclean: 5459 * 5460 * Sets portions of a page valid and clean. The arguments are expected 5461 * to be DEV_BSIZE aligned but if they aren't the bitmap is inclusive 5462 * of any partial chunks touched by the range. The invalid portion of 5463 * such chunks will be zero'd. 5464 * 5465 * (base + size) must be less then or equal to PAGE_SIZE. 5466 */ 5467 void 5468 vm_page_set_validclean(vm_page_t m, int base, int size) 5469 { 5470 vm_page_bits_t oldvalid, pagebits; 5471 int endoff, frag; 5472 5473 vm_page_assert_busied(m); 5474 if (size == 0) /* handle degenerate case */ 5475 return; 5476 5477 /* 5478 * If the base is not DEV_BSIZE aligned and the valid 5479 * bit is clear, we have to zero out a portion of the 5480 * first block. 5481 */ 5482 if ((frag = rounddown2(base, DEV_BSIZE)) != base && 5483 (m->valid & ((vm_page_bits_t)1 << (base >> DEV_BSHIFT))) == 0) 5484 pmap_zero_page_area(m, frag, base - frag); 5485 5486 /* 5487 * If the ending offset is not DEV_BSIZE aligned and the 5488 * valid bit is clear, we have to zero out a portion of 5489 * the last block. 5490 */ 5491 endoff = base + size; 5492 if ((frag = rounddown2(endoff, DEV_BSIZE)) != endoff && 5493 (m->valid & ((vm_page_bits_t)1 << (endoff >> DEV_BSHIFT))) == 0) 5494 pmap_zero_page_area(m, endoff, 5495 DEV_BSIZE - (endoff & (DEV_BSIZE - 1))); 5496 5497 /* 5498 * Set valid, clear dirty bits. If validating the entire 5499 * page we can safely clear the pmap modify bit. We also 5500 * use this opportunity to clear the PGA_NOSYNC flag. If a process 5501 * takes a write fault on a MAP_NOSYNC memory area the flag will 5502 * be set again. 5503 * 5504 * We set valid bits inclusive of any overlap, but we can only 5505 * clear dirty bits for DEV_BSIZE chunks that are fully within 5506 * the range. 5507 */ 5508 oldvalid = m->valid; 5509 pagebits = vm_page_bits(base, size); 5510 if (vm_page_xbusied(m)) 5511 m->valid |= pagebits; 5512 else 5513 vm_page_bits_set(m, &m->valid, pagebits); 5514 #if 0 /* NOT YET */ 5515 if ((frag = base & (DEV_BSIZE - 1)) != 0) { 5516 frag = DEV_BSIZE - frag; 5517 base += frag; 5518 size -= frag; 5519 if (size < 0) 5520 size = 0; 5521 } 5522 pagebits = vm_page_bits(base, size & (DEV_BSIZE - 1)); 5523 #endif 5524 if (base == 0 && size == PAGE_SIZE) { 5525 /* 5526 * The page can only be modified within the pmap if it is 5527 * mapped, and it can only be mapped if it was previously 5528 * fully valid. 5529 */ 5530 if (oldvalid == VM_PAGE_BITS_ALL) 5531 /* 5532 * Perform the pmap_clear_modify() first. Otherwise, 5533 * a concurrent pmap operation, such as 5534 * pmap_protect(), could clear a modification in the 5535 * pmap and set the dirty field on the page before 5536 * pmap_clear_modify() had begun and after the dirty 5537 * field was cleared here. 5538 */ 5539 pmap_clear_modify(m); 5540 m->dirty = 0; 5541 vm_page_aflag_clear(m, PGA_NOSYNC); 5542 } else if (oldvalid != VM_PAGE_BITS_ALL && vm_page_xbusied(m)) 5543 m->dirty &= ~pagebits; 5544 else 5545 vm_page_clear_dirty_mask(m, pagebits); 5546 } 5547 5548 void 5549 vm_page_clear_dirty(vm_page_t m, int base, int size) 5550 { 5551 5552 vm_page_clear_dirty_mask(m, vm_page_bits(base, size)); 5553 } 5554 5555 /* 5556 * vm_page_set_invalid: 5557 * 5558 * Invalidates DEV_BSIZE'd chunks within a page. Both the 5559 * valid and dirty bits for the effected areas are cleared. 5560 */ 5561 void 5562 vm_page_set_invalid(vm_page_t m, int base, int size) 5563 { 5564 vm_page_bits_t bits; 5565 vm_object_t object; 5566 5567 /* 5568 * The object lock is required so that pages can't be mapped 5569 * read-only while we're in the process of invalidating them. 5570 */ 5571 object = m->object; 5572 VM_OBJECT_ASSERT_WLOCKED(object); 5573 vm_page_assert_busied(m); 5574 5575 if (object->type == OBJT_VNODE && base == 0 && IDX_TO_OFF(m->pindex) + 5576 size >= object->un_pager.vnp.vnp_size) 5577 bits = VM_PAGE_BITS_ALL; 5578 else 5579 bits = vm_page_bits(base, size); 5580 if (object->ref_count != 0 && vm_page_all_valid(m) && bits != 0) 5581 pmap_remove_all(m); 5582 KASSERT((bits == 0 && vm_page_all_valid(m)) || 5583 !pmap_page_is_mapped(m), 5584 ("vm_page_set_invalid: page %p is mapped", m)); 5585 if (vm_page_xbusied(m)) { 5586 m->valid &= ~bits; 5587 m->dirty &= ~bits; 5588 } else { 5589 vm_page_bits_clear(m, &m->valid, bits); 5590 vm_page_bits_clear(m, &m->dirty, bits); 5591 } 5592 } 5593 5594 /* 5595 * vm_page_invalid: 5596 * 5597 * Invalidates the entire page. The page must be busy, unmapped, and 5598 * the enclosing object must be locked. The object locks protects 5599 * against concurrent read-only pmap enter which is done without 5600 * busy. 5601 */ 5602 void 5603 vm_page_invalid(vm_page_t m) 5604 { 5605 5606 vm_page_assert_busied(m); 5607 VM_OBJECT_ASSERT_WLOCKED(m->object); 5608 MPASS(!pmap_page_is_mapped(m)); 5609 5610 if (vm_page_xbusied(m)) 5611 m->valid = 0; 5612 else 5613 vm_page_bits_clear(m, &m->valid, VM_PAGE_BITS_ALL); 5614 } 5615 5616 /* 5617 * vm_page_zero_invalid() 5618 * 5619 * The kernel assumes that the invalid portions of a page contain 5620 * garbage, but such pages can be mapped into memory by user code. 5621 * When this occurs, we must zero out the non-valid portions of the 5622 * page so user code sees what it expects. 5623 * 5624 * Pages are most often semi-valid when the end of a file is mapped 5625 * into memory and the file's size is not page aligned. 5626 */ 5627 void 5628 vm_page_zero_invalid(vm_page_t m, boolean_t setvalid) 5629 { 5630 int b; 5631 int i; 5632 5633 /* 5634 * Scan the valid bits looking for invalid sections that 5635 * must be zeroed. Invalid sub-DEV_BSIZE'd areas ( where the 5636 * valid bit may be set ) have already been zeroed by 5637 * vm_page_set_validclean(). 5638 */ 5639 for (b = i = 0; i <= PAGE_SIZE / DEV_BSIZE; ++i) { 5640 if (i == (PAGE_SIZE / DEV_BSIZE) || 5641 (m->valid & ((vm_page_bits_t)1 << i))) { 5642 if (i > b) { 5643 pmap_zero_page_area(m, 5644 b << DEV_BSHIFT, (i - b) << DEV_BSHIFT); 5645 } 5646 b = i + 1; 5647 } 5648 } 5649 5650 /* 5651 * setvalid is TRUE when we can safely set the zero'd areas 5652 * as being valid. We can do this if there are no cache consistency 5653 * issues. e.g. it is ok to do with UFS, but not ok to do with NFS. 5654 */ 5655 if (setvalid) 5656 vm_page_valid(m); 5657 } 5658 5659 /* 5660 * vm_page_is_valid: 5661 * 5662 * Is (partial) page valid? Note that the case where size == 0 5663 * will return FALSE in the degenerate case where the page is 5664 * entirely invalid, and TRUE otherwise. 5665 * 5666 * Some callers envoke this routine without the busy lock held and 5667 * handle races via higher level locks. Typical callers should 5668 * hold a busy lock to prevent invalidation. 5669 */ 5670 int 5671 vm_page_is_valid(vm_page_t m, int base, int size) 5672 { 5673 vm_page_bits_t bits; 5674 5675 bits = vm_page_bits(base, size); 5676 return (vm_page_any_valid(m) && (m->valid & bits) == bits); 5677 } 5678 5679 /* 5680 * Returns true if all of the specified predicates are true for the entire 5681 * (super)page and false otherwise. 5682 */ 5683 bool 5684 vm_page_ps_test(vm_page_t m, int psind, int flags, vm_page_t skip_m) 5685 { 5686 vm_object_t object; 5687 int i, npages; 5688 5689 object = m->object; 5690 if (skip_m != NULL && skip_m->object != object) 5691 return (false); 5692 VM_OBJECT_ASSERT_LOCKED(object); 5693 KASSERT(psind <= m->psind, 5694 ("psind %d > psind %d of m %p", psind, m->psind, m)); 5695 npages = atop(pagesizes[psind]); 5696 5697 /* 5698 * The physically contiguous pages that make up a superpage, i.e., a 5699 * page with a page size index ("psind") greater than zero, will 5700 * occupy adjacent entries in vm_page_array[]. 5701 */ 5702 for (i = 0; i < npages; i++) { 5703 /* Always test object consistency, including "skip_m". */ 5704 if (m[i].object != object) 5705 return (false); 5706 if (&m[i] == skip_m) 5707 continue; 5708 if ((flags & PS_NONE_BUSY) != 0 && vm_page_busied(&m[i])) 5709 return (false); 5710 if ((flags & PS_ALL_DIRTY) != 0) { 5711 /* 5712 * Calling vm_page_test_dirty() or pmap_is_modified() 5713 * might stop this case from spuriously returning 5714 * "false". However, that would require a write lock 5715 * on the object containing "m[i]". 5716 */ 5717 if (m[i].dirty != VM_PAGE_BITS_ALL) 5718 return (false); 5719 } 5720 if ((flags & PS_ALL_VALID) != 0 && 5721 m[i].valid != VM_PAGE_BITS_ALL) 5722 return (false); 5723 } 5724 return (true); 5725 } 5726 5727 /* 5728 * Set the page's dirty bits if the page is modified. 5729 */ 5730 void 5731 vm_page_test_dirty(vm_page_t m) 5732 { 5733 5734 vm_page_assert_busied(m); 5735 if (m->dirty != VM_PAGE_BITS_ALL && pmap_is_modified(m)) 5736 vm_page_dirty(m); 5737 } 5738 5739 void 5740 vm_page_valid(vm_page_t m) 5741 { 5742 5743 vm_page_assert_busied(m); 5744 if (vm_page_xbusied(m)) 5745 m->valid = VM_PAGE_BITS_ALL; 5746 else 5747 vm_page_bits_set(m, &m->valid, VM_PAGE_BITS_ALL); 5748 } 5749 5750 void 5751 vm_page_lock_KBI(vm_page_t m, const char *file, int line) 5752 { 5753 5754 mtx_lock_flags_(vm_page_lockptr(m), 0, file, line); 5755 } 5756 5757 void 5758 vm_page_unlock_KBI(vm_page_t m, const char *file, int line) 5759 { 5760 5761 mtx_unlock_flags_(vm_page_lockptr(m), 0, file, line); 5762 } 5763 5764 int 5765 vm_page_trylock_KBI(vm_page_t m, const char *file, int line) 5766 { 5767 5768 return (mtx_trylock_flags_(vm_page_lockptr(m), 0, file, line)); 5769 } 5770 5771 #if defined(INVARIANTS) || defined(INVARIANT_SUPPORT) 5772 void 5773 vm_page_assert_locked_KBI(vm_page_t m, const char *file, int line) 5774 { 5775 5776 vm_page_lock_assert_KBI(m, MA_OWNED, file, line); 5777 } 5778 5779 void 5780 vm_page_lock_assert_KBI(vm_page_t m, int a, const char *file, int line) 5781 { 5782 5783 mtx_assert_(vm_page_lockptr(m), a, file, line); 5784 } 5785 #endif 5786 5787 #ifdef INVARIANTS 5788 void 5789 vm_page_object_busy_assert(vm_page_t m) 5790 { 5791 5792 /* 5793 * Certain of the page's fields may only be modified by the 5794 * holder of a page or object busy. 5795 */ 5796 if (m->object != NULL && !vm_page_busied(m)) 5797 VM_OBJECT_ASSERT_BUSY(m->object); 5798 } 5799 5800 void 5801 vm_page_assert_pga_writeable(vm_page_t m, uint16_t bits) 5802 { 5803 5804 if ((bits & PGA_WRITEABLE) == 0) 5805 return; 5806 5807 /* 5808 * The PGA_WRITEABLE flag can only be set if the page is 5809 * managed, is exclusively busied or the object is locked. 5810 * Currently, this flag is only set by pmap_enter(). 5811 */ 5812 KASSERT((m->oflags & VPO_UNMANAGED) == 0, 5813 ("PGA_WRITEABLE on unmanaged page")); 5814 if (!vm_page_xbusied(m)) 5815 VM_OBJECT_ASSERT_BUSY(m->object); 5816 } 5817 #endif 5818 5819 #include "opt_ddb.h" 5820 #ifdef DDB 5821 #include <sys/kernel.h> 5822 5823 #include <ddb/ddb.h> 5824 5825 DB_SHOW_COMMAND_FLAGS(page, vm_page_print_page_info, DB_CMD_MEMSAFE) 5826 { 5827 5828 db_printf("vm_cnt.v_free_count: %d\n", vm_free_count()); 5829 db_printf("vm_cnt.v_inactive_count: %d\n", vm_inactive_count()); 5830 db_printf("vm_cnt.v_active_count: %d\n", vm_active_count()); 5831 db_printf("vm_cnt.v_laundry_count: %d\n", vm_laundry_count()); 5832 db_printf("vm_cnt.v_wire_count: %d\n", vm_wire_count()); 5833 db_printf("vm_cnt.v_free_reserved: %d\n", vm_cnt.v_free_reserved); 5834 db_printf("vm_cnt.v_free_min: %d\n", vm_cnt.v_free_min); 5835 db_printf("vm_cnt.v_free_target: %d\n", vm_cnt.v_free_target); 5836 db_printf("vm_cnt.v_inactive_target: %d\n", vm_cnt.v_inactive_target); 5837 } 5838 5839 DB_SHOW_COMMAND_FLAGS(pageq, vm_page_print_pageq_info, DB_CMD_MEMSAFE) 5840 { 5841 int dom; 5842 5843 db_printf("pq_free %d\n", vm_free_count()); 5844 for (dom = 0; dom < vm_ndomains; dom++) { 5845 db_printf( 5846 "dom %d page_cnt %d free %d pq_act %d pq_inact %d pq_laund %d pq_unsw %d\n", 5847 dom, 5848 vm_dom[dom].vmd_page_count, 5849 vm_dom[dom].vmd_free_count, 5850 vm_dom[dom].vmd_pagequeues[PQ_ACTIVE].pq_cnt, 5851 vm_dom[dom].vmd_pagequeues[PQ_INACTIVE].pq_cnt, 5852 vm_dom[dom].vmd_pagequeues[PQ_LAUNDRY].pq_cnt, 5853 vm_dom[dom].vmd_pagequeues[PQ_UNSWAPPABLE].pq_cnt); 5854 } 5855 } 5856 5857 DB_SHOW_COMMAND(pginfo, vm_page_print_pginfo) 5858 { 5859 vm_page_t m; 5860 boolean_t phys, virt; 5861 5862 if (!have_addr) { 5863 db_printf("show pginfo addr\n"); 5864 return; 5865 } 5866 5867 phys = strchr(modif, 'p') != NULL; 5868 virt = strchr(modif, 'v') != NULL; 5869 if (virt) 5870 m = PHYS_TO_VM_PAGE(pmap_kextract(addr)); 5871 else if (phys) 5872 m = PHYS_TO_VM_PAGE(addr); 5873 else 5874 m = (vm_page_t)addr; 5875 db_printf( 5876 "page %p obj %p pidx 0x%jx phys 0x%jx q %d ref 0x%x\n" 5877 " af 0x%x of 0x%x f 0x%x act %d busy %x valid 0x%x dirty 0x%x\n", 5878 m, m->object, (uintmax_t)m->pindex, (uintmax_t)m->phys_addr, 5879 m->a.queue, m->ref_count, m->a.flags, m->oflags, 5880 m->flags, m->a.act_count, m->busy_lock, m->valid, m->dirty); 5881 } 5882 #endif /* DDB */ 5883