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