1/*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2002-2006 Rice University 5 * Copyright (c) 2007-2011 Alan L. Cox <alc@cs.rice.edu> 6 * All rights reserved. 7 * 8 * This software was developed for the FreeBSD Project by Alan L. Cox, 9 * Olivier Crameri, Peter Druschel, Sitaram Iyer, and Juan Navarro. 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 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 23 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 24 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY 30 * WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 * POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34/* 35 * Superpage reservation management module 36 * 37 * Any external functions defined by this module are only to be used by the 38 * virtual memory system. 39 */ 40 41#include <sys/cdefs.h> 42#include "opt_vm.h" 43 44#include <sys/param.h> 45#include <sys/kernel.h> 46#include <sys/lock.h> 47#include <sys/malloc.h> 48#include <sys/mutex.h> 49#include <sys/queue.h> 50#include <sys/rwlock.h> 51#include <sys/sbuf.h> 52#include <sys/sysctl.h> 53#include <sys/systm.h> 54#include <sys/bitstring.h> 55#include <sys/counter.h> 56#include <sys/ktr.h> 57#include <sys/vmmeter.h> 58#include <sys/smp.h> 59 60#include <vm/vm.h> 61#include <vm/vm_extern.h> 62#include <vm/vm_param.h> 63#include <vm/vm_object.h> 64#include <vm/vm_page.h> 65#include <vm/vm_pageout.h> 66#include <vm/vm_pagequeue.h> 67#include <vm/vm_phys.h> 68#include <vm/vm_radix.h> 69#include <vm/vm_reserv.h> 70 71/* 72 * The reservation system supports the speculative allocation of large physical 73 * pages ("superpages"). Speculative allocation enables the fully automatic 74 * utilization of superpages by the virtual memory system. In other words, no 75 * programmatic directives are required to use superpages. 76 */ 77 78#if VM_NRESERVLEVEL > 0 79 80#ifndef VM_LEVEL_0_ORDER_MAX 81#define VM_LEVEL_0_ORDER_MAX VM_LEVEL_0_ORDER 82#endif 83 84/* 85 * The number of small pages that are contained in a level 0 reservation 86 */ 87#define VM_LEVEL_0_NPAGES (1 << VM_LEVEL_0_ORDER) 88#define VM_LEVEL_0_NPAGES_MAX (1 << VM_LEVEL_0_ORDER_MAX) 89 90/* 91 * The number of bits by which a physical address is shifted to obtain the 92 * reservation number 93 */ 94#define VM_LEVEL_0_SHIFT (VM_LEVEL_0_ORDER + PAGE_SHIFT) 95 96/* 97 * The size of a level 0 reservation in bytes 98 */ 99#define VM_LEVEL_0_SIZE (1 << VM_LEVEL_0_SHIFT) 100 101/* 102 * Computes the index of the small page underlying the given (object, pindex) 103 * within the reservation's array of small pages. 104 */ 105#define VM_RESERV_INDEX(object, pindex) \ 106 (((object)->pg_color + (pindex)) & (VM_LEVEL_0_NPAGES - 1)) 107 108/* 109 * Number of elapsed ticks before we update the LRU queue position. Used 110 * to reduce contention and churn on the list. 111 */ 112#define PARTPOPSLOP 1 113 114/* 115 * The reservation structure 116 * 117 * A reservation structure is constructed whenever a large physical page is 118 * speculatively allocated to an object. The reservation provides the small 119 * physical pages for the range [pindex, pindex + VM_LEVEL_0_NPAGES) of offsets 120 * within that object. The reservation's "popcnt" tracks the number of these 121 * small physical pages that are in use at any given time. When and if the 122 * reservation is not fully utilized, it appears in the queue of partially 123 * populated reservations. The reservation always appears on the containing 124 * object's list of reservations. 125 * 126 * A partially populated reservation can be broken and reclaimed at any time. 127 * 128 * c - constant after boot 129 * d - vm_reserv_domain_lock 130 * o - vm_reserv_object_lock 131 * r - vm_reserv_lock 132 * s - vm_reserv_domain_scan_lock 133 */ 134struct vm_reserv { 135 struct mtx lock; /* reservation lock. */ 136 TAILQ_ENTRY(vm_reserv) partpopq; /* (d, r) per-domain queue. */ 137 LIST_ENTRY(vm_reserv) objq; /* (o, r) object queue */ 138 vm_object_t object; /* (o, r) containing object */ 139 vm_pindex_t pindex; /* (o, r) offset in object */ 140 vm_page_t pages; /* (c) first page */ 141 uint16_t popcnt; /* (r) # of pages in use */ 142 uint8_t domain; /* (c) NUMA domain. */ 143 char inpartpopq; /* (d, r) */ 144 int lasttick; /* (r) last pop update tick. */ 145 bitstr_t bit_decl(popmap, VM_LEVEL_0_NPAGES_MAX); 146 /* (r) bit vector, used pages */ 147}; 148 149TAILQ_HEAD(vm_reserv_queue, vm_reserv); 150 151#define vm_reserv_lockptr(rv) (&(rv)->lock) 152#define vm_reserv_assert_locked(rv) \ 153 mtx_assert(vm_reserv_lockptr(rv), MA_OWNED) 154#define vm_reserv_lock(rv) mtx_lock(vm_reserv_lockptr(rv)) 155#define vm_reserv_trylock(rv) mtx_trylock(vm_reserv_lockptr(rv)) 156#define vm_reserv_unlock(rv) mtx_unlock(vm_reserv_lockptr(rv)) 157 158/* 159 * The reservation array 160 * 161 * This array is analoguous in function to vm_page_array. It differs in the 162 * respect that it may contain a greater number of useful reservation 163 * structures than there are (physical) superpages. These "invalid" 164 * reservation structures exist to trade-off space for time in the 165 * implementation of vm_reserv_from_page(). Invalid reservation structures are 166 * distinguishable from "valid" reservation structures by inspecting the 167 * reservation's "pages" field. Invalid reservation structures have a NULL 168 * "pages" field. 169 * 170 * vm_reserv_from_page() maps a small (physical) page to an element of this 171 * array by computing a physical reservation number from the page's physical 172 * address. The physical reservation number is used as the array index. 173 * 174 * An "active" reservation is a valid reservation structure that has a non-NULL 175 * "object" field and a non-zero "popcnt" field. In other words, every active 176 * reservation belongs to a particular object. Moreover, every active 177 * reservation has an entry in the containing object's list of reservations. 178 */ 179static vm_reserv_t vm_reserv_array; 180 181/* 182 * The per-domain partially populated reservation queues 183 * 184 * These queues enable the fast recovery of an unused free small page from a 185 * partially populated reservation. The reservation at the head of a queue 186 * is the least recently changed, partially populated reservation. 187 * 188 * Access to this queue is synchronized by the per-domain reservation lock. 189 * Threads reclaiming free pages from the queue must hold the per-domain scan 190 * lock. 191 */ 192struct vm_reserv_domain { 193 struct mtx lock; 194 struct vm_reserv_queue partpop; /* (d) */ 195 struct vm_reserv marker; /* (d, s) scan marker/lock */ 196} __aligned(CACHE_LINE_SIZE); 197 198static struct vm_reserv_domain vm_rvd[MAXMEMDOM]; 199 200#define vm_reserv_domain_lockptr(d) (&vm_rvd[(d)].lock) 201#define vm_reserv_domain_assert_locked(d) \ 202 mtx_assert(vm_reserv_domain_lockptr(d), MA_OWNED) 203#define vm_reserv_domain_lock(d) mtx_lock(vm_reserv_domain_lockptr(d)) 204#define vm_reserv_domain_unlock(d) mtx_unlock(vm_reserv_domain_lockptr(d)) 205 206#define vm_reserv_domain_scan_lock(d) mtx_lock(&vm_rvd[(d)].marker.lock) 207#define vm_reserv_domain_scan_unlock(d) mtx_unlock(&vm_rvd[(d)].marker.lock) 208 209static SYSCTL_NODE(_vm, OID_AUTO, reserv, CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 210 "Reservation Info"); 211 212static COUNTER_U64_DEFINE_EARLY(vm_reserv_broken); 213SYSCTL_COUNTER_U64(_vm_reserv, OID_AUTO, broken, CTLFLAG_RD, 214 &vm_reserv_broken, "Cumulative number of broken reservations"); 215 216static COUNTER_U64_DEFINE_EARLY(vm_reserv_freed); 217SYSCTL_COUNTER_U64(_vm_reserv, OID_AUTO, freed, CTLFLAG_RD, 218 &vm_reserv_freed, "Cumulative number of freed reservations"); 219 220static int sysctl_vm_reserv_fullpop(SYSCTL_HANDLER_ARGS); 221 222SYSCTL_PROC(_vm_reserv, OID_AUTO, fullpop, CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RD, 223 NULL, 0, sysctl_vm_reserv_fullpop, "I", "Current number of full reservations"); 224 225static int sysctl_vm_reserv_partpopq(SYSCTL_HANDLER_ARGS); 226 227SYSCTL_OID(_vm_reserv, OID_AUTO, partpopq, 228 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, 0, 229 sysctl_vm_reserv_partpopq, "A", 230 "Partially populated reservation queues"); 231 232static COUNTER_U64_DEFINE_EARLY(vm_reserv_reclaimed); 233SYSCTL_COUNTER_U64(_vm_reserv, OID_AUTO, reclaimed, CTLFLAG_RD, 234 &vm_reserv_reclaimed, "Cumulative number of reclaimed reservations"); 235 236/* 237 * The object lock pool is used to synchronize the rvq. We can not use a 238 * pool mutex because it is required before malloc works. 239 * 240 * The "hash" function could be made faster without divide and modulo. 241 */ 242#define VM_RESERV_OBJ_LOCK_COUNT MAXCPU 243 244struct mtx_padalign vm_reserv_object_mtx[VM_RESERV_OBJ_LOCK_COUNT]; 245 246#define vm_reserv_object_lock_idx(object) \ 247 (((uintptr_t)object / sizeof(*object)) % VM_RESERV_OBJ_LOCK_COUNT) 248#define vm_reserv_object_lock_ptr(object) \ 249 &vm_reserv_object_mtx[vm_reserv_object_lock_idx((object))] 250#define vm_reserv_object_lock(object) \ 251 mtx_lock(vm_reserv_object_lock_ptr((object))) 252#define vm_reserv_object_unlock(object) \ 253 mtx_unlock(vm_reserv_object_lock_ptr((object))) 254 255static void vm_reserv_break(vm_reserv_t rv); 256static void vm_reserv_depopulate(vm_reserv_t rv, int index); 257static vm_reserv_t vm_reserv_from_page(vm_page_t m); 258static boolean_t vm_reserv_has_pindex(vm_reserv_t rv, 259 vm_pindex_t pindex); 260static void vm_reserv_populate(vm_reserv_t rv, int index); 261static void vm_reserv_reclaim(vm_reserv_t rv); 262 263/* 264 * Returns the current number of full reservations. 265 * 266 * Since the number of full reservations is computed without acquiring any 267 * locks, the returned value is inexact. 268 */ 269static int 270sysctl_vm_reserv_fullpop(SYSCTL_HANDLER_ARGS) 271{ 272 vm_paddr_t paddr; 273 struct vm_phys_seg *seg; 274 vm_reserv_t rv; 275 int fullpop, segind; 276 277 fullpop = 0; 278 for (segind = 0; segind < vm_phys_nsegs; segind++) { 279 seg = &vm_phys_segs[segind]; 280 paddr = roundup2(seg->start, VM_LEVEL_0_SIZE); 281#ifdef VM_PHYSSEG_SPARSE 282 rv = seg->first_reserv + (paddr >> VM_LEVEL_0_SHIFT) - 283 (seg->start >> VM_LEVEL_0_SHIFT); 284#else 285 rv = &vm_reserv_array[paddr >> VM_LEVEL_0_SHIFT]; 286#endif 287 while (paddr + VM_LEVEL_0_SIZE > paddr && paddr + 288 VM_LEVEL_0_SIZE <= seg->end) { 289 fullpop += rv->popcnt == VM_LEVEL_0_NPAGES; 290 paddr += VM_LEVEL_0_SIZE; 291 rv++; 292 } 293 } 294 return (sysctl_handle_int(oidp, &fullpop, 0, req)); 295} 296 297/* 298 * Describes the current state of the partially populated reservation queue. 299 */ 300static int 301sysctl_vm_reserv_partpopq(SYSCTL_HANDLER_ARGS) 302{ 303 struct sbuf sbuf; 304 vm_reserv_t rv; 305 int counter, error, domain, level, unused_pages; 306 307 error = sysctl_wire_old_buffer(req, 0); 308 if (error != 0) 309 return (error); 310 sbuf_new_for_sysctl(&sbuf, NULL, 128, req); 311 sbuf_printf(&sbuf, "\nDOMAIN LEVEL SIZE NUMBER\n\n"); 312 for (domain = 0; domain < vm_ndomains; domain++) { 313 for (level = -1; level <= VM_NRESERVLEVEL - 2; level++) { 314 counter = 0; 315 unused_pages = 0; 316 vm_reserv_domain_lock(domain); 317 TAILQ_FOREACH(rv, &vm_rvd[domain].partpop, partpopq) { 318 if (rv == &vm_rvd[domain].marker) 319 continue; 320 counter++; 321 unused_pages += VM_LEVEL_0_NPAGES - rv->popcnt; 322 } 323 vm_reserv_domain_unlock(domain); 324 sbuf_printf(&sbuf, "%6d, %7d, %6dK, %6d\n", 325 domain, level, 326 unused_pages * ((int)PAGE_SIZE / 1024), counter); 327 } 328 } 329 error = sbuf_finish(&sbuf); 330 sbuf_delete(&sbuf); 331 return (error); 332} 333 334/* 335 * Remove a reservation from the object's objq. 336 */ 337static void 338vm_reserv_remove(vm_reserv_t rv) 339{ 340 vm_object_t object; 341 342 vm_reserv_assert_locked(rv); 343 CTR5(KTR_VM, "%s: rv %p object %p popcnt %d inpartpop %d", 344 __FUNCTION__, rv, rv->object, rv->popcnt, rv->inpartpopq); 345 KASSERT(rv->object != NULL, 346 ("vm_reserv_remove: reserv %p is free", rv)); 347 KASSERT(!rv->inpartpopq, 348 ("vm_reserv_remove: reserv %p's inpartpopq is TRUE", rv)); 349 object = rv->object; 350 vm_reserv_object_lock(object); 351 LIST_REMOVE(rv, objq); 352 rv->object = NULL; 353 vm_reserv_object_unlock(object); 354} 355 356/* 357 * Insert a new reservation into the object's objq. 358 */ 359static void 360vm_reserv_insert(vm_reserv_t rv, vm_object_t object, vm_pindex_t pindex) 361{ 362 363 vm_reserv_assert_locked(rv); 364 CTR6(KTR_VM, 365 "%s: rv %p(%p) object %p new %p popcnt %d", 366 __FUNCTION__, rv, rv->pages, rv->object, object, 367 rv->popcnt); 368 KASSERT(rv->object == NULL, 369 ("vm_reserv_insert: reserv %p isn't free", rv)); 370 KASSERT(rv->popcnt == 0, 371 ("vm_reserv_insert: reserv %p's popcnt is corrupted", rv)); 372 KASSERT(!rv->inpartpopq, 373 ("vm_reserv_insert: reserv %p's inpartpopq is TRUE", rv)); 374 KASSERT(bit_ntest(rv->popmap, 0, VM_LEVEL_0_NPAGES - 1, 0), 375 ("vm_reserv_insert: reserv %p's popmap is corrupted", rv)); 376 vm_reserv_object_lock(object); 377 rv->pindex = pindex; 378 rv->object = object; 379 rv->lasttick = ticks; 380 LIST_INSERT_HEAD(&object->rvq, rv, objq); 381 vm_reserv_object_unlock(object); 382} 383 384/* 385 * Reduces the given reservation's population count. If the population count 386 * becomes zero, the reservation is destroyed. Additionally, moves the 387 * reservation to the tail of the partially populated reservation queue if the 388 * population count is non-zero. 389 */ 390static void 391vm_reserv_depopulate(vm_reserv_t rv, int index) 392{ 393 struct vm_domain *vmd; 394 395 vm_reserv_assert_locked(rv); 396 CTR5(KTR_VM, "%s: rv %p object %p popcnt %d inpartpop %d", 397 __FUNCTION__, rv, rv->object, rv->popcnt, rv->inpartpopq); 398 KASSERT(rv->object != NULL, 399 ("vm_reserv_depopulate: reserv %p is free", rv)); 400 KASSERT(bit_test(rv->popmap, index), 401 ("vm_reserv_depopulate: reserv %p's popmap[%d] is clear", rv, 402 index)); 403 KASSERT(rv->popcnt > 0, 404 ("vm_reserv_depopulate: reserv %p's popcnt is corrupted", rv)); 405 KASSERT(rv->domain < vm_ndomains, 406 ("vm_reserv_depopulate: reserv %p's domain is corrupted %d", 407 rv, rv->domain)); 408 if (rv->popcnt == VM_LEVEL_0_NPAGES) { 409 KASSERT(rv->pages->psind == 1, 410 ("vm_reserv_depopulate: reserv %p is already demoted", 411 rv)); 412 rv->pages->psind = 0; 413 } 414 bit_clear(rv->popmap, index); 415 rv->popcnt--; 416 if ((unsigned)(ticks - rv->lasttick) >= PARTPOPSLOP || 417 rv->popcnt == 0) { 418 vm_reserv_domain_lock(rv->domain); 419 if (rv->inpartpopq) { 420 TAILQ_REMOVE(&vm_rvd[rv->domain].partpop, rv, partpopq); 421 rv->inpartpopq = FALSE; 422 } 423 if (rv->popcnt != 0) { 424 rv->inpartpopq = TRUE; 425 TAILQ_INSERT_TAIL(&vm_rvd[rv->domain].partpop, rv, 426 partpopq); 427 } 428 vm_reserv_domain_unlock(rv->domain); 429 rv->lasttick = ticks; 430 } 431 vmd = VM_DOMAIN(rv->domain); 432 if (rv->popcnt == 0) { 433 vm_reserv_remove(rv); 434 vm_domain_free_lock(vmd); 435 vm_phys_free_pages(rv->pages, VM_LEVEL_0_ORDER); 436 vm_domain_free_unlock(vmd); 437 counter_u64_add(vm_reserv_freed, 1); 438 } 439 vm_domain_freecnt_inc(vmd, 1); 440} 441 442/* 443 * Returns the reservation to which the given page might belong. 444 */ 445static __inline vm_reserv_t 446vm_reserv_from_page(vm_page_t m) 447{ 448#ifdef VM_PHYSSEG_SPARSE 449 struct vm_phys_seg *seg; 450 451 seg = &vm_phys_segs[m->segind]; 452 return (seg->first_reserv + (VM_PAGE_TO_PHYS(m) >> VM_LEVEL_0_SHIFT) - 453 (seg->start >> VM_LEVEL_0_SHIFT)); 454#else 455 return (&vm_reserv_array[VM_PAGE_TO_PHYS(m) >> VM_LEVEL_0_SHIFT]); 456#endif 457} 458 459/* 460 * Returns an existing reservation or NULL and initialized successor pointer. 461 */ 462static vm_reserv_t 463vm_reserv_from_object(vm_object_t object, vm_pindex_t pindex, 464 vm_page_t mpred, vm_page_t *msuccp) 465{ 466 vm_reserv_t rv; 467 vm_page_t msucc; 468 469 msucc = NULL; 470 if (mpred != NULL) { 471 KASSERT(mpred->object == object, 472 ("vm_reserv_from_object: object doesn't contain mpred")); 473 KASSERT(mpred->pindex < pindex, 474 ("vm_reserv_from_object: mpred doesn't precede pindex")); 475 rv = vm_reserv_from_page(mpred); 476 if (rv->object == object && vm_reserv_has_pindex(rv, pindex)) 477 goto found; 478 msucc = TAILQ_NEXT(mpred, listq); 479 } else 480 msucc = TAILQ_FIRST(&object->memq); 481 if (msucc != NULL) { 482 KASSERT(msucc->pindex > pindex, 483 ("vm_reserv_from_object: msucc doesn't succeed pindex")); 484 rv = vm_reserv_from_page(msucc); 485 if (rv->object == object && vm_reserv_has_pindex(rv, pindex)) 486 goto found; 487 } 488 rv = NULL; 489 490found: 491 *msuccp = msucc; 492 493 return (rv); 494} 495 496/* 497 * Returns TRUE if the given reservation contains the given page index and 498 * FALSE otherwise. 499 */ 500static __inline boolean_t 501vm_reserv_has_pindex(vm_reserv_t rv, vm_pindex_t pindex) 502{ 503 504 return (((pindex - rv->pindex) & ~(VM_LEVEL_0_NPAGES - 1)) == 0); 505} 506 507/* 508 * Increases the given reservation's population count. Moves the reservation 509 * to the tail of the partially populated reservation queue. 510 */ 511static void 512vm_reserv_populate(vm_reserv_t rv, int index) 513{ 514 515 vm_reserv_assert_locked(rv); 516 CTR5(KTR_VM, "%s: rv %p object %p popcnt %d inpartpop %d", 517 __FUNCTION__, rv, rv->object, rv->popcnt, rv->inpartpopq); 518 KASSERT(rv->object != NULL, 519 ("vm_reserv_populate: reserv %p is free", rv)); 520 KASSERT(!bit_test(rv->popmap, index), 521 ("vm_reserv_populate: reserv %p's popmap[%d] is set", rv, 522 index)); 523 KASSERT(rv->popcnt < VM_LEVEL_0_NPAGES, 524 ("vm_reserv_populate: reserv %p is already full", rv)); 525 KASSERT(rv->pages->psind == 0, 526 ("vm_reserv_populate: reserv %p is already promoted", rv)); 527 KASSERT(rv->domain < vm_ndomains, 528 ("vm_reserv_populate: reserv %p's domain is corrupted %d", 529 rv, rv->domain)); 530 bit_set(rv->popmap, index); 531 rv->popcnt++; 532 if ((unsigned)(ticks - rv->lasttick) < PARTPOPSLOP && 533 rv->inpartpopq && rv->popcnt != VM_LEVEL_0_NPAGES) 534 return; 535 rv->lasttick = ticks; 536 vm_reserv_domain_lock(rv->domain); 537 if (rv->inpartpopq) { 538 TAILQ_REMOVE(&vm_rvd[rv->domain].partpop, rv, partpopq); 539 rv->inpartpopq = FALSE; 540 } 541 if (rv->popcnt < VM_LEVEL_0_NPAGES) { 542 rv->inpartpopq = TRUE; 543 TAILQ_INSERT_TAIL(&vm_rvd[rv->domain].partpop, rv, partpopq); 544 } else { 545 KASSERT(rv->pages->psind == 0, 546 ("vm_reserv_populate: reserv %p is already promoted", 547 rv)); 548 rv->pages->psind = 1; 549 } 550 vm_reserv_domain_unlock(rv->domain); 551} 552 553/* 554 * Allocates a contiguous set of physical pages of the given size "npages" 555 * from existing or newly created reservations. All of the physical pages 556 * must be at or above the given physical address "low" and below the given 557 * physical address "high". The given value "alignment" determines the 558 * alignment of the first physical page in the set. If the given value 559 * "boundary" is non-zero, then the set of physical pages cannot cross any 560 * physical address boundary that is a multiple of that value. Both 561 * "alignment" and "boundary" must be a power of two. 562 * 563 * The page "mpred" must immediately precede the offset "pindex" within the 564 * specified object. 565 * 566 * The object must be locked. 567 */ 568vm_page_t 569vm_reserv_alloc_contig(vm_object_t object, vm_pindex_t pindex, int domain, 570 int req, vm_page_t mpred, u_long npages, vm_paddr_t low, vm_paddr_t high, 571 u_long alignment, vm_paddr_t boundary) 572{ 573 struct vm_domain *vmd; 574 vm_paddr_t pa, size; 575 vm_page_t m, m_ret, msucc; 576 vm_pindex_t first, leftcap, rightcap; 577 vm_reserv_t rv; 578 u_long allocpages, maxpages, minpages; 579 int i, index, n; 580 581 VM_OBJECT_ASSERT_WLOCKED(object); 582 KASSERT(npages != 0, ("vm_reserv_alloc_contig: npages is 0")); 583 584 /* 585 * Is a reservation fundamentally impossible? 586 */ 587 if (pindex < VM_RESERV_INDEX(object, pindex) || 588 pindex + npages > object->size) 589 return (NULL); 590 591 /* 592 * All reservations of a particular size have the same alignment. 593 * Assuming that the first page is allocated from a reservation, the 594 * least significant bits of its physical address can be determined 595 * from its offset from the beginning of the reservation and the size 596 * of the reservation. 597 * 598 * Could the specified index within a reservation of the smallest 599 * possible size satisfy the alignment and boundary requirements? 600 */ 601 pa = VM_RESERV_INDEX(object, pindex) << PAGE_SHIFT; 602 size = npages << PAGE_SHIFT; 603 if (!vm_addr_ok(pa, size, alignment, boundary)) 604 return (NULL); 605 606 /* 607 * Look for an existing reservation. 608 */ 609 rv = vm_reserv_from_object(object, pindex, mpred, &msucc); 610 if (rv != NULL) { 611 KASSERT(object != kernel_object || rv->domain == domain, 612 ("vm_reserv_alloc_contig: domain mismatch")); 613 index = VM_RESERV_INDEX(object, pindex); 614 /* Does the allocation fit within the reservation? */ 615 if (index + npages > VM_LEVEL_0_NPAGES) 616 return (NULL); 617 domain = rv->domain; 618 vmd = VM_DOMAIN(domain); 619 vm_reserv_lock(rv); 620 /* Handle reclaim race. */ 621 if (rv->object != object) 622 goto out; 623 m = &rv->pages[index]; 624 pa = VM_PAGE_TO_PHYS(m); 625 if (pa < low || pa + size > high || 626 !vm_addr_ok(pa, size, alignment, boundary)) 627 goto out; 628 /* Handle vm_page_rename(m, new_object, ...). */ 629 if (!bit_ntest(rv->popmap, index, index + npages - 1, 0)) 630 goto out; 631 if (!vm_domain_allocate(vmd, req, npages)) 632 goto out; 633 for (i = 0; i < npages; i++) 634 vm_reserv_populate(rv, index + i); 635 vm_reserv_unlock(rv); 636 return (m); 637out: 638 vm_reserv_unlock(rv); 639 return (NULL); 640 } 641 642 /* 643 * Could at least one reservation fit between the first index to the 644 * left that can be used ("leftcap") and the first index to the right 645 * that cannot be used ("rightcap")? 646 * 647 * We must synchronize with the reserv object lock to protect the 648 * pindex/object of the resulting reservations against rename while 649 * we are inspecting. 650 */ 651 first = pindex - VM_RESERV_INDEX(object, pindex); 652 minpages = VM_RESERV_INDEX(object, pindex) + npages; 653 maxpages = roundup2(minpages, VM_LEVEL_0_NPAGES); 654 allocpages = maxpages; 655 vm_reserv_object_lock(object); 656 if (mpred != NULL) { 657 if ((rv = vm_reserv_from_page(mpred))->object != object) 658 leftcap = mpred->pindex + 1; 659 else 660 leftcap = rv->pindex + VM_LEVEL_0_NPAGES; 661 if (leftcap > first) { 662 vm_reserv_object_unlock(object); 663 return (NULL); 664 } 665 } 666 if (msucc != NULL) { 667 if ((rv = vm_reserv_from_page(msucc))->object != object) 668 rightcap = msucc->pindex; 669 else 670 rightcap = rv->pindex; 671 if (first + maxpages > rightcap) { 672 if (maxpages == VM_LEVEL_0_NPAGES) { 673 vm_reserv_object_unlock(object); 674 return (NULL); 675 } 676 677 /* 678 * At least one reservation will fit between "leftcap" 679 * and "rightcap". However, a reservation for the 680 * last of the requested pages will not fit. Reduce 681 * the size of the upcoming allocation accordingly. 682 */ 683 allocpages = minpages; 684 } 685 } 686 vm_reserv_object_unlock(object); 687 688 /* 689 * Would the last new reservation extend past the end of the object? 690 * 691 * If the object is unlikely to grow don't allocate a reservation for 692 * the tail. 693 */ 694 if ((object->flags & OBJ_ANON) == 0 && 695 first + maxpages > object->size) { 696 if (maxpages == VM_LEVEL_0_NPAGES) 697 return (NULL); 698 allocpages = minpages; 699 } 700 701 /* 702 * Allocate the physical pages. The alignment and boundary specified 703 * for this allocation may be different from the alignment and 704 * boundary specified for the requested pages. For instance, the 705 * specified index may not be the first page within the first new 706 * reservation. 707 */ 708 m = NULL; 709 vmd = VM_DOMAIN(domain); 710 if (vm_domain_allocate(vmd, req, npages)) { 711 vm_domain_free_lock(vmd); 712 m = vm_phys_alloc_contig(domain, allocpages, low, high, 713 ulmax(alignment, VM_LEVEL_0_SIZE), 714 boundary > VM_LEVEL_0_SIZE ? boundary : 0); 715 vm_domain_free_unlock(vmd); 716 if (m == NULL) { 717 vm_domain_freecnt_inc(vmd, npages); 718 return (NULL); 719 } 720 } else 721 return (NULL); 722 KASSERT(vm_page_domain(m) == domain, 723 ("vm_reserv_alloc_contig: Page domain does not match requested.")); 724 725 /* 726 * The allocated physical pages always begin at a reservation 727 * boundary, but they do not always end at a reservation boundary. 728 * Initialize every reservation that is completely covered by the 729 * allocated physical pages. 730 */ 731 m_ret = NULL; 732 index = VM_RESERV_INDEX(object, pindex); 733 do { 734 rv = vm_reserv_from_page(m); 735 KASSERT(rv->pages == m, 736 ("vm_reserv_alloc_contig: reserv %p's pages is corrupted", 737 rv)); 738 vm_reserv_lock(rv); 739 vm_reserv_insert(rv, object, first); 740 n = ulmin(VM_LEVEL_0_NPAGES - index, npages); 741 for (i = 0; i < n; i++) 742 vm_reserv_populate(rv, index + i); 743 npages -= n; 744 if (m_ret == NULL) { 745 m_ret = &rv->pages[index]; 746 index = 0; 747 } 748 vm_reserv_unlock(rv); 749 m += VM_LEVEL_0_NPAGES; 750 first += VM_LEVEL_0_NPAGES; 751 allocpages -= VM_LEVEL_0_NPAGES; 752 } while (allocpages >= VM_LEVEL_0_NPAGES); 753 return (m_ret); 754} 755 756/* 757 * Allocate a physical page from an existing or newly created reservation. 758 * 759 * The page "mpred" must immediately precede the offset "pindex" within the 760 * specified object. 761 * 762 * The object must be locked. 763 */ 764vm_page_t 765vm_reserv_alloc_page(vm_object_t object, vm_pindex_t pindex, int domain, 766 int req, vm_page_t mpred) 767{ 768 struct vm_domain *vmd; 769 vm_page_t m, msucc; 770 vm_pindex_t first, leftcap, rightcap; 771 vm_reserv_t rv; 772 int index; 773 774 VM_OBJECT_ASSERT_WLOCKED(object); 775 776 /* 777 * Is a reservation fundamentally impossible? 778 */ 779 if (pindex < VM_RESERV_INDEX(object, pindex) || 780 pindex >= object->size) 781 return (NULL); 782 783 /* 784 * Look for an existing reservation. 785 */ 786 rv = vm_reserv_from_object(object, pindex, mpred, &msucc); 787 if (rv != NULL) { 788 KASSERT(object != kernel_object || rv->domain == domain, 789 ("vm_reserv_alloc_page: domain mismatch")); 790 domain = rv->domain; 791 vmd = VM_DOMAIN(domain); 792 index = VM_RESERV_INDEX(object, pindex); 793 m = &rv->pages[index]; 794 vm_reserv_lock(rv); 795 /* Handle reclaim race. */ 796 if (rv->object != object || 797 /* Handle vm_page_rename(m, new_object, ...). */ 798 bit_test(rv->popmap, index)) { 799 m = NULL; 800 goto out; 801 } 802 if (vm_domain_allocate(vmd, req, 1) == 0) 803 m = NULL; 804 else 805 vm_reserv_populate(rv, index); 806out: 807 vm_reserv_unlock(rv); 808 return (m); 809 } 810 811 /* 812 * Could a reservation fit between the first index to the left that 813 * can be used and the first index to the right that cannot be used? 814 * 815 * We must synchronize with the reserv object lock to protect the 816 * pindex/object of the resulting reservations against rename while 817 * we are inspecting. 818 */ 819 first = pindex - VM_RESERV_INDEX(object, pindex); 820 vm_reserv_object_lock(object); 821 if (mpred != NULL) { 822 if ((rv = vm_reserv_from_page(mpred))->object != object) 823 leftcap = mpred->pindex + 1; 824 else 825 leftcap = rv->pindex + VM_LEVEL_0_NPAGES; 826 if (leftcap > first) { 827 vm_reserv_object_unlock(object); 828 return (NULL); 829 } 830 } 831 if (msucc != NULL) { 832 if ((rv = vm_reserv_from_page(msucc))->object != object) 833 rightcap = msucc->pindex; 834 else 835 rightcap = rv->pindex; 836 if (first + VM_LEVEL_0_NPAGES > rightcap) { 837 vm_reserv_object_unlock(object); 838 return (NULL); 839 } 840 } 841 vm_reserv_object_unlock(object); 842 843 /* 844 * Would the last new reservation extend past the end of the object? 845 * 846 * If the object is unlikely to grow don't allocate a reservation for 847 * the tail. 848 */ 849 if ((object->flags & OBJ_ANON) == 0 && 850 first + VM_LEVEL_0_NPAGES > object->size) 851 return (NULL); 852 853 /* 854 * Allocate and populate the new reservation. 855 */ 856 m = NULL; 857 vmd = VM_DOMAIN(domain); 858 if (vm_domain_allocate(vmd, req, 1)) { 859 vm_domain_free_lock(vmd); 860 m = vm_phys_alloc_pages(domain, VM_FREEPOOL_DEFAULT, 861 VM_LEVEL_0_ORDER); 862 vm_domain_free_unlock(vmd); 863 if (m == NULL) { 864 vm_domain_freecnt_inc(vmd, 1); 865 return (NULL); 866 } 867 } else 868 return (NULL); 869 rv = vm_reserv_from_page(m); 870 vm_reserv_lock(rv); 871 KASSERT(rv->pages == m, 872 ("vm_reserv_alloc_page: reserv %p's pages is corrupted", rv)); 873 vm_reserv_insert(rv, object, first); 874 index = VM_RESERV_INDEX(object, pindex); 875 vm_reserv_populate(rv, index); 876 vm_reserv_unlock(rv); 877 878 return (&rv->pages[index]); 879} 880 881/* 882 * Breaks the given reservation. All free pages in the reservation 883 * are returned to the physical memory allocator. The reservation's 884 * population count and map are reset to their initial state. 885 * 886 * The given reservation must not be in the partially populated reservation 887 * queue. 888 */ 889static void 890vm_reserv_break(vm_reserv_t rv) 891{ 892 int hi, lo, pos; 893 894 vm_reserv_assert_locked(rv); 895 CTR5(KTR_VM, "%s: rv %p object %p popcnt %d inpartpop %d", 896 __FUNCTION__, rv, rv->object, rv->popcnt, rv->inpartpopq); 897 vm_reserv_remove(rv); 898 rv->pages->psind = 0; 899 hi = lo = -1; 900 pos = 0; 901 for (;;) { 902 bit_ff_at(rv->popmap, pos, VM_LEVEL_0_NPAGES, lo != hi, &pos); 903 if (lo == hi) { 904 if (pos == -1) 905 break; 906 lo = pos; 907 continue; 908 } 909 if (pos == -1) 910 pos = VM_LEVEL_0_NPAGES; 911 hi = pos; 912 vm_domain_free_lock(VM_DOMAIN(rv->domain)); 913 vm_phys_enqueue_contig(&rv->pages[lo], hi - lo); 914 vm_domain_free_unlock(VM_DOMAIN(rv->domain)); 915 lo = hi; 916 } 917 bit_nclear(rv->popmap, 0, VM_LEVEL_0_NPAGES - 1); 918 rv->popcnt = 0; 919 counter_u64_add(vm_reserv_broken, 1); 920} 921 922/* 923 * Breaks all reservations belonging to the given object. 924 */ 925void 926vm_reserv_break_all(vm_object_t object) 927{ 928 vm_reserv_t rv; 929 930 /* 931 * This access of object->rvq is unsynchronized so that the 932 * object rvq lock can nest after the domain_free lock. We 933 * must check for races in the results. However, the object 934 * lock prevents new additions, so we are guaranteed that when 935 * it returns NULL the object is properly empty. 936 */ 937 while ((rv = LIST_FIRST(&object->rvq)) != NULL) { 938 vm_reserv_lock(rv); 939 /* Reclaim race. */ 940 if (rv->object != object) { 941 vm_reserv_unlock(rv); 942 continue; 943 } 944 vm_reserv_domain_lock(rv->domain); 945 if (rv->inpartpopq) { 946 TAILQ_REMOVE(&vm_rvd[rv->domain].partpop, rv, partpopq); 947 rv->inpartpopq = FALSE; 948 } 949 vm_reserv_domain_unlock(rv->domain); 950 vm_reserv_break(rv); 951 vm_reserv_unlock(rv); 952 } 953} 954 955/* 956 * Frees the given page if it belongs to a reservation. Returns TRUE if the 957 * page is freed and FALSE otherwise. 958 */ 959boolean_t 960vm_reserv_free_page(vm_page_t m) 961{ 962 vm_reserv_t rv; 963 boolean_t ret; 964 965 rv = vm_reserv_from_page(m); 966 if (rv->object == NULL) 967 return (FALSE); 968 vm_reserv_lock(rv); 969 /* Re-validate after lock. */ 970 if (rv->object != NULL) { 971 vm_reserv_depopulate(rv, m - rv->pages); 972 ret = TRUE; 973 } else 974 ret = FALSE; 975 vm_reserv_unlock(rv); 976 977 return (ret); 978} 979 980/* 981 * Initializes the reservation management system. Specifically, initializes 982 * the reservation array. 983 * 984 * Requires that vm_page_array and first_page are initialized! 985 */ 986void 987vm_reserv_init(void) 988{ 989 vm_paddr_t paddr; 990 struct vm_phys_seg *seg; 991 struct vm_reserv *rv; 992 struct vm_reserv_domain *rvd; 993#ifdef VM_PHYSSEG_SPARSE 994 vm_pindex_t used; 995#endif 996 int i, segind; 997 998 /* 999 * Initialize the reservation array. Specifically, initialize the 1000 * "pages" field for every element that has an underlying superpage. 1001 */ 1002#ifdef VM_PHYSSEG_SPARSE 1003 used = 0; 1004#endif 1005 for (segind = 0; segind < vm_phys_nsegs; segind++) { 1006 seg = &vm_phys_segs[segind]; 1007#ifdef VM_PHYSSEG_SPARSE 1008 seg->first_reserv = &vm_reserv_array[used]; 1009 used += howmany(seg->end, VM_LEVEL_0_SIZE) - 1010 seg->start / VM_LEVEL_0_SIZE; 1011#else 1012 seg->first_reserv = 1013 &vm_reserv_array[seg->start >> VM_LEVEL_0_SHIFT]; 1014#endif 1015 paddr = roundup2(seg->start, VM_LEVEL_0_SIZE); 1016 rv = seg->first_reserv + (paddr >> VM_LEVEL_0_SHIFT) - 1017 (seg->start >> VM_LEVEL_0_SHIFT); 1018 while (paddr + VM_LEVEL_0_SIZE > paddr && paddr + 1019 VM_LEVEL_0_SIZE <= seg->end) { 1020 rv->pages = PHYS_TO_VM_PAGE(paddr); 1021 rv->domain = seg->domain; 1022 mtx_init(&rv->lock, "vm reserv", NULL, MTX_DEF); 1023 paddr += VM_LEVEL_0_SIZE; 1024 rv++; 1025 } 1026 } 1027 for (i = 0; i < MAXMEMDOM; i++) { 1028 rvd = &vm_rvd[i]; 1029 mtx_init(&rvd->lock, "vm reserv domain", NULL, MTX_DEF); 1030 TAILQ_INIT(&rvd->partpop); 1031 mtx_init(&rvd->marker.lock, "vm reserv marker", NULL, MTX_DEF); 1032 1033 /* 1034 * Fully populated reservations should never be present in the 1035 * partially populated reservation queues. 1036 */ 1037 rvd->marker.popcnt = VM_LEVEL_0_NPAGES; 1038 bit_nset(rvd->marker.popmap, 0, VM_LEVEL_0_NPAGES - 1); 1039 } 1040 1041 for (i = 0; i < VM_RESERV_OBJ_LOCK_COUNT; i++) 1042 mtx_init(&vm_reserv_object_mtx[i], "resv obj lock", NULL, 1043 MTX_DEF); 1044} 1045 1046/* 1047 * Returns true if the given page belongs to a reservation and that page is 1048 * free. Otherwise, returns false. 1049 */ 1050bool 1051vm_reserv_is_page_free(vm_page_t m) 1052{ 1053 vm_reserv_t rv; 1054 1055 rv = vm_reserv_from_page(m); 1056 if (rv->object == NULL) 1057 return (false); 1058 return (!bit_test(rv->popmap, m - rv->pages)); 1059} 1060 1061/* 1062 * Returns true if the given page is part of a block of npages, starting at a 1063 * multiple of npages, that are all allocated. Otherwise, returns false. 1064 */ 1065bool 1066vm_reserv_is_populated(vm_page_t m, int npages) 1067{ 1068 vm_reserv_t rv; 1069 int index; 1070 1071 KASSERT(npages <= VM_LEVEL_0_NPAGES, 1072 ("%s: npages %d exceeds VM_LEVEL_0_NPAGES", __func__, npages)); 1073 KASSERT(powerof2(npages), 1074 ("%s: npages %d is not a power of 2", __func__, npages)); 1075 rv = vm_reserv_from_page(m); 1076 if (rv->object == NULL) 1077 return (false); 1078 index = rounddown2(m - rv->pages, npages); 1079 return (bit_ntest(rv->popmap, index, index + npages - 1, 1)); 1080} 1081 1082/* 1083 * If the given page belongs to a reservation, returns the level of that 1084 * reservation. Otherwise, returns -1. 1085 */ 1086int 1087vm_reserv_level(vm_page_t m) 1088{ 1089 vm_reserv_t rv; 1090 1091 rv = vm_reserv_from_page(m); 1092 return (rv->object != NULL ? 0 : -1); 1093} 1094 1095/* 1096 * Returns a reservation level if the given page belongs to a fully populated 1097 * reservation and -1 otherwise. 1098 */ 1099int 1100vm_reserv_level_iffullpop(vm_page_t m) 1101{ 1102 vm_reserv_t rv; 1103 1104 rv = vm_reserv_from_page(m); 1105 return (rv->popcnt == VM_LEVEL_0_NPAGES ? 0 : -1); 1106} 1107 1108/* 1109 * Remove a partially populated reservation from the queue. 1110 */ 1111static void 1112vm_reserv_dequeue(vm_reserv_t rv) 1113{ 1114 1115 vm_reserv_domain_assert_locked(rv->domain); 1116 vm_reserv_assert_locked(rv); 1117 CTR5(KTR_VM, "%s: rv %p object %p popcnt %d inpartpop %d", 1118 __FUNCTION__, rv, rv->object, rv->popcnt, rv->inpartpopq); 1119 KASSERT(rv->inpartpopq, 1120 ("vm_reserv_reclaim: reserv %p's inpartpopq is FALSE", rv)); 1121 1122 TAILQ_REMOVE(&vm_rvd[rv->domain].partpop, rv, partpopq); 1123 rv->inpartpopq = FALSE; 1124} 1125 1126/* 1127 * Breaks the given partially populated reservation, releasing its free pages 1128 * to the physical memory allocator. 1129 */ 1130static void 1131vm_reserv_reclaim(vm_reserv_t rv) 1132{ 1133 1134 vm_reserv_assert_locked(rv); 1135 CTR5(KTR_VM, "%s: rv %p object %p popcnt %d inpartpop %d", 1136 __FUNCTION__, rv, rv->object, rv->popcnt, rv->inpartpopq); 1137 if (rv->inpartpopq) { 1138 vm_reserv_domain_lock(rv->domain); 1139 vm_reserv_dequeue(rv); 1140 vm_reserv_domain_unlock(rv->domain); 1141 } 1142 vm_reserv_break(rv); 1143 counter_u64_add(vm_reserv_reclaimed, 1); 1144} 1145 1146/* 1147 * Breaks a reservation near the head of the partially populated reservation 1148 * queue, releasing its free pages to the physical memory allocator. Returns 1149 * TRUE if a reservation is broken and FALSE otherwise. 1150 */ 1151bool 1152vm_reserv_reclaim_inactive(int domain) 1153{ 1154 vm_reserv_t rv; 1155 1156 vm_reserv_domain_lock(domain); 1157 TAILQ_FOREACH(rv, &vm_rvd[domain].partpop, partpopq) { 1158 /* 1159 * A locked reservation is likely being updated or reclaimed, 1160 * so just skip ahead. 1161 */ 1162 if (rv != &vm_rvd[domain].marker && vm_reserv_trylock(rv)) { 1163 vm_reserv_dequeue(rv); 1164 break; 1165 } 1166 } 1167 vm_reserv_domain_unlock(domain); 1168 if (rv != NULL) { 1169 vm_reserv_reclaim(rv); 1170 vm_reserv_unlock(rv); 1171 return (true); 1172 } 1173 return (false); 1174} 1175 1176/* 1177 * Determine whether this reservation has free pages that satisfy the given 1178 * request for contiguous physical memory. Start searching from the lower 1179 * bound, defined by lo, and stop at the upper bound, hi. Return the index 1180 * of the first satisfactory free page, or -1 if none is found. 1181 */ 1182static int 1183vm_reserv_find_contig(vm_reserv_t rv, int npages, int lo, 1184 int hi, int ppn_align, int ppn_bound) 1185{ 1186 1187 vm_reserv_assert_locked(rv); 1188 KASSERT(npages <= VM_LEVEL_0_NPAGES - 1, 1189 ("%s: Too many pages", __func__)); 1190 KASSERT(ppn_bound <= VM_LEVEL_0_NPAGES, 1191 ("%s: Too big a boundary for reservation size", __func__)); 1192 KASSERT(npages <= ppn_bound, 1193 ("%s: Too many pages for given boundary", __func__)); 1194 KASSERT(ppn_align != 0 && powerof2(ppn_align), 1195 ("ppn_align is not a positive power of 2")); 1196 KASSERT(ppn_bound != 0 && powerof2(ppn_bound), 1197 ("ppn_bound is not a positive power of 2")); 1198 while (bit_ffc_area_at(rv->popmap, lo, hi, npages, &lo), lo != -1) { 1199 if (lo < roundup2(lo, ppn_align)) { 1200 /* Skip to next aligned page. */ 1201 lo = roundup2(lo, ppn_align); 1202 } else if (roundup2(lo + 1, ppn_bound) >= lo + npages) 1203 return (lo); 1204 if (roundup2(lo + 1, ppn_bound) < lo + npages) { 1205 /* Skip to next boundary-matching page. */ 1206 lo = roundup2(lo + 1, ppn_bound); 1207 } 1208 } 1209 return (-1); 1210} 1211 1212/* 1213 * Searches the partially populated reservation queue for the least recently 1214 * changed reservation with free pages that satisfy the given request for 1215 * contiguous physical memory. If a satisfactory reservation is found, it is 1216 * broken. Returns a page if a reservation is broken and NULL otherwise. 1217 */ 1218vm_page_t 1219vm_reserv_reclaim_contig(int domain, u_long npages, vm_paddr_t low, 1220 vm_paddr_t high, u_long alignment, vm_paddr_t boundary) 1221{ 1222 struct vm_reserv_queue *queue; 1223 vm_paddr_t pa, size; 1224 vm_page_t m_ret; 1225 vm_reserv_t marker, rv, rvn; 1226 int hi, lo, posn, ppn_align, ppn_bound; 1227 1228 KASSERT(npages > 0, ("npages is 0")); 1229 KASSERT(powerof2(alignment), ("alignment is not a power of 2")); 1230 KASSERT(powerof2(boundary), ("boundary is not a power of 2")); 1231 if (npages > VM_LEVEL_0_NPAGES - 1) 1232 return (NULL); 1233 size = npages << PAGE_SHIFT; 1234 /* 1235 * Ensure that a free range starting at a boundary-multiple 1236 * doesn't include a boundary-multiple within it. Otherwise, 1237 * no boundary-constrained allocation is possible. 1238 */ 1239 if (!vm_addr_bound_ok(0, size, boundary)) 1240 return (NULL); 1241 marker = &vm_rvd[domain].marker; 1242 queue = &vm_rvd[domain].partpop; 1243 /* 1244 * Compute shifted alignment, boundary values for page-based 1245 * calculations. Constrain to range [1, VM_LEVEL_0_NPAGES] to 1246 * avoid overflow. 1247 */ 1248 ppn_align = (int)(ulmin(ulmax(PAGE_SIZE, alignment), 1249 VM_LEVEL_0_SIZE) >> PAGE_SHIFT); 1250 ppn_bound = boundary == 0 ? VM_LEVEL_0_NPAGES : 1251 (int)(MIN(MAX(PAGE_SIZE, boundary), 1252 VM_LEVEL_0_SIZE) >> PAGE_SHIFT); 1253 1254 vm_reserv_domain_scan_lock(domain); 1255 vm_reserv_domain_lock(domain); 1256 TAILQ_FOREACH_SAFE(rv, queue, partpopq, rvn) { 1257 pa = VM_PAGE_TO_PHYS(&rv->pages[0]); 1258 if (pa + VM_LEVEL_0_SIZE - size < low) { 1259 /* This entire reservation is too low; go to next. */ 1260 continue; 1261 } 1262 if (pa + size > high) { 1263 /* This entire reservation is too high; go to next. */ 1264 continue; 1265 } 1266 if (!vm_addr_align_ok(pa, alignment)) { 1267 /* This entire reservation is unaligned; go to next. */ 1268 continue; 1269 } 1270 1271 if (vm_reserv_trylock(rv) == 0) { 1272 TAILQ_INSERT_AFTER(queue, rv, marker, partpopq); 1273 vm_reserv_domain_unlock(domain); 1274 vm_reserv_lock(rv); 1275 if (TAILQ_PREV(marker, vm_reserv_queue, partpopq) != 1276 rv) { 1277 vm_reserv_unlock(rv); 1278 vm_reserv_domain_lock(domain); 1279 rvn = TAILQ_NEXT(marker, partpopq); 1280 TAILQ_REMOVE(queue, marker, partpopq); 1281 continue; 1282 } 1283 vm_reserv_domain_lock(domain); 1284 TAILQ_REMOVE(queue, marker, partpopq); 1285 } 1286 vm_reserv_domain_unlock(domain); 1287 lo = (pa >= low) ? 0 : 1288 (int)((low + PAGE_MASK - pa) >> PAGE_SHIFT); 1289 hi = (pa + VM_LEVEL_0_SIZE <= high) ? VM_LEVEL_0_NPAGES : 1290 (int)((high - pa) >> PAGE_SHIFT); 1291 posn = vm_reserv_find_contig(rv, (int)npages, lo, hi, 1292 ppn_align, ppn_bound); 1293 if (posn >= 0) { 1294 vm_reserv_domain_scan_unlock(domain); 1295 /* Allocate requested space */ 1296 rv->popcnt += npages; 1297 bit_nset(rv->popmap, posn, posn + npages - 1); 1298 vm_reserv_reclaim(rv); 1299 vm_reserv_unlock(rv); 1300 m_ret = &rv->pages[posn]; 1301 pa = VM_PAGE_TO_PHYS(m_ret); 1302 KASSERT(vm_addr_ok(pa, size, alignment, boundary), 1303 ("%s: adjusted address not aligned/bounded to " 1304 "%lx/%jx", 1305 __func__, alignment, (uintmax_t)boundary)); 1306 return (m_ret); 1307 } 1308 vm_reserv_domain_lock(domain); 1309 rvn = TAILQ_NEXT(rv, partpopq); 1310 vm_reserv_unlock(rv); 1311 } 1312 vm_reserv_domain_unlock(domain); 1313 vm_reserv_domain_scan_unlock(domain); 1314 return (NULL); 1315} 1316 1317/* 1318 * Transfers the reservation underlying the given page to a new object. 1319 * 1320 * The object must be locked. 1321 */ 1322void 1323vm_reserv_rename(vm_page_t m, vm_object_t new_object, vm_object_t old_object, 1324 vm_pindex_t old_object_offset) 1325{ 1326 vm_reserv_t rv; 1327 1328 VM_OBJECT_ASSERT_WLOCKED(new_object); 1329 rv = vm_reserv_from_page(m); 1330 if (rv->object == old_object) { 1331 vm_reserv_lock(rv); 1332 CTR6(KTR_VM, 1333 "%s: rv %p object %p new %p popcnt %d inpartpop %d", 1334 __FUNCTION__, rv, rv->object, new_object, rv->popcnt, 1335 rv->inpartpopq); 1336 if (rv->object == old_object) { 1337 vm_reserv_object_lock(old_object); 1338 rv->object = NULL; 1339 LIST_REMOVE(rv, objq); 1340 vm_reserv_object_unlock(old_object); 1341 vm_reserv_object_lock(new_object); 1342 rv->object = new_object; 1343 rv->pindex -= old_object_offset; 1344 LIST_INSERT_HEAD(&new_object->rvq, rv, objq); 1345 vm_reserv_object_unlock(new_object); 1346 } 1347 vm_reserv_unlock(rv); 1348 } 1349} 1350 1351/* 1352 * Returns the size (in bytes) of a reservation of the specified level. 1353 */ 1354int 1355vm_reserv_size(int level) 1356{ 1357 1358 switch (level) { 1359 case 0: 1360 return (VM_LEVEL_0_SIZE); 1361 case -1: 1362 return (PAGE_SIZE); 1363 default: 1364 return (0); 1365 } 1366} 1367 1368/* 1369 * Allocates the virtual and physical memory required by the reservation 1370 * management system's data structures, in particular, the reservation array. 1371 */ 1372vm_paddr_t 1373vm_reserv_startup(vm_offset_t *vaddr, vm_paddr_t end) 1374{ 1375 vm_paddr_t new_end; 1376 vm_pindex_t count; 1377 size_t size; 1378 int i; 1379 1380 count = 0; 1381 for (i = 0; i < vm_phys_nsegs; i++) { 1382#ifdef VM_PHYSSEG_SPARSE 1383 count += howmany(vm_phys_segs[i].end, VM_LEVEL_0_SIZE) - 1384 vm_phys_segs[i].start / VM_LEVEL_0_SIZE; 1385#else 1386 count = MAX(count, 1387 howmany(vm_phys_segs[i].end, VM_LEVEL_0_SIZE)); 1388#endif 1389 } 1390 1391 for (i = 0; phys_avail[i + 1] != 0; i += 2) { 1392#ifdef VM_PHYSSEG_SPARSE 1393 count += howmany(phys_avail[i + 1], VM_LEVEL_0_SIZE) - 1394 phys_avail[i] / VM_LEVEL_0_SIZE; 1395#else 1396 count = MAX(count, 1397 howmany(phys_avail[i + 1], VM_LEVEL_0_SIZE)); 1398#endif 1399 } 1400 1401 /* 1402 * Calculate the size (in bytes) of the reservation array. Rounding up 1403 * for partial superpages at boundaries, as every small page is mapped 1404 * to an element in the reservation array based on its physical address. 1405 * Thus, the number of elements in the reservation array can be greater 1406 * than the number of superpages. 1407 */ 1408 size = count * sizeof(struct vm_reserv); 1409 1410 /* 1411 * Allocate and map the physical memory for the reservation array. The 1412 * next available virtual address is returned by reference. 1413 */ 1414 new_end = end - round_page(size); 1415 vm_reserv_array = (void *)(uintptr_t)pmap_map(vaddr, new_end, end, 1416 VM_PROT_READ | VM_PROT_WRITE); 1417 bzero(vm_reserv_array, size); 1418 1419 /* 1420 * Return the next available physical address. 1421 */ 1422 return (new_end); 1423} 1424 1425/* 1426 * Returns the superpage containing the given page. 1427 */ 1428vm_page_t 1429vm_reserv_to_superpage(vm_page_t m) 1430{ 1431 vm_reserv_t rv; 1432 1433 VM_OBJECT_ASSERT_LOCKED(m->object); 1434 rv = vm_reserv_from_page(m); 1435 if (rv->object == m->object && rv->popcnt == VM_LEVEL_0_NPAGES) 1436 m = rv->pages; 1437 else 1438 m = NULL; 1439 1440 return (m); 1441} 1442 1443#endif /* VM_NRESERVLEVEL > 0 */ 1444