sys/vm/vm_phys.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2002-2006 Rice University
   5  * Copyright (c) 2007 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  *      Physical memory system implementation
  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 __FBSDID("$FreeBSD$");
  43
  44 #include "opt_ddb.h"
  45 #include "opt_vm.h"
  46
  47 #include <sys/param.h>
  48 #include <sys/systm.h>
  49 #include <sys/lock.h>
  50 #include <sys/kernel.h>
  51 #include <sys/malloc.h>
  52 #include <sys/mutex.h>
  53 #include <sys/proc.h>
  54 #include <sys/queue.h>
  55 #include <sys/rwlock.h>
  56 #include <sys/sbuf.h>
  57 #include <sys/sysctl.h>
  58 #include <sys/tree.h>
  59 #include <sys/vmmeter.h>
  60 #include <sys/seq.h>
  61
  62 #include <ddb/ddb.h>
  63
  64 #include <vm/vm.h>
  65 #include <vm/vm_param.h>
  66 #include <vm/vm_kern.h>
  67 #include <vm/vm_object.h>
  68 #include <vm/vm_page.h>
  69 #include <vm/vm_phys.h>
  70
  71 _Static_assert(sizeof(long) * NBBY >= VM_PHYSSEG_MAX,
  72     "Too many physsegs.");
  73
  74 #ifdef NUMA
  75 struct mem_affinity *mem_affinity;
  76 int *mem_locality;
  77 #endif
  78
  79 int vm_ndomains = 1;
  80
  81 struct vm_phys_seg vm_phys_segs[VM_PHYSSEG_MAX];
  82 int vm_phys_nsegs;
  83
  84 struct vm_phys_fictitious_seg;
  85 static int vm_phys_fictitious_cmp(struct vm_phys_fictitious_seg *,
  86     struct vm_phys_fictitious_seg *);
  87
  88 RB_HEAD(fict_tree, vm_phys_fictitious_seg) vm_phys_fictitious_tree =
  89     RB_INITIALIZER(_vm_phys_fictitious_tree);
  90
  91 struct vm_phys_fictitious_seg {
  92         RB_ENTRY(vm_phys_fictitious_seg) node;
  93         /* Memory region data */
  94         vm_paddr_t      start;
  95         vm_paddr_t      end;
  96         vm_page_t       first_page;
  97 };
  98
  99 RB_GENERATE_STATIC(fict_tree, vm_phys_fictitious_seg, node,
 100     vm_phys_fictitious_cmp);
 101
 102 static struct rwlock vm_phys_fictitious_reg_lock;
 103 MALLOC_DEFINE(M_FICT_PAGES, "vm_fictitious", "Fictitious VM pages");
 104
 105 static struct vm_freelist
 106     vm_phys_free_queues[MAXMEMDOM][VM_NFREELIST][VM_NFREEPOOL][VM_NFREEORDER];
 107
 108 static int vm_nfreelists;
 109
 110 /*
 111  * Provides the mapping from VM_FREELIST_* to free list indices (flind).
 112  */
 113 static int vm_freelist_to_flind[VM_NFREELIST];
 114
 115 CTASSERT(VM_FREELIST_DEFAULT == 0);
 116
 117 #ifdef VM_FREELIST_ISADMA
 118 #define VM_ISADMA_BOUNDARY      16777216
 119 #endif
 120 #ifdef VM_FREELIST_DMA32
 121 #define VM_DMA32_BOUNDARY       ((vm_paddr_t)1 << 32)
 122 #endif
 123
 124 /*
 125  * Enforce the assumptions made by vm_phys_add_seg() and vm_phys_init() about
 126  * the ordering of the free list boundaries.
 127  */
 128 #if defined(VM_ISADMA_BOUNDARY) && defined(VM_LOWMEM_BOUNDARY)
 129 CTASSERT(VM_ISADMA_BOUNDARY < VM_LOWMEM_BOUNDARY);
 130 #endif
 131 #if defined(VM_LOWMEM_BOUNDARY) && defined(VM_DMA32_BOUNDARY)
 132 CTASSERT(VM_LOWMEM_BOUNDARY < VM_DMA32_BOUNDARY);
 133 #endif
 134
 135 static int sysctl_vm_phys_free(SYSCTL_HANDLER_ARGS);
 136 SYSCTL_OID(_vm, OID_AUTO, phys_free, CTLTYPE_STRING | CTLFLAG_RD,
 137     NULL, 0, sysctl_vm_phys_free, "A", "Phys Free Info");
 138
 139 static int sysctl_vm_phys_segs(SYSCTL_HANDLER_ARGS);
 140 SYSCTL_OID(_vm, OID_AUTO, phys_segs, CTLTYPE_STRING | CTLFLAG_RD,
 141     NULL, 0, sysctl_vm_phys_segs, "A", "Phys Seg Info");
 142
 143 #ifdef NUMA
 144 static int sysctl_vm_phys_locality(SYSCTL_HANDLER_ARGS);
 145 SYSCTL_OID(_vm, OID_AUTO, phys_locality, CTLTYPE_STRING | CTLFLAG_RD,
 146     NULL, 0, sysctl_vm_phys_locality, "A", "Phys Locality Info");
 147 #endif
 148
 149 SYSCTL_INT(_vm, OID_AUTO, ndomains, CTLFLAG_RD,
 150     &vm_ndomains, 0, "Number of physical memory domains available.");
 151
 152 static vm_page_t vm_phys_alloc_seg_contig(struct vm_phys_seg *seg,
 153     u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment,
 154     vm_paddr_t boundary);
 155 static void _vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int domain);
 156 static void vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end);
 157 static void vm_phys_split_pages(vm_page_t m, int oind, struct vm_freelist *fl,
 158     int order);
 159
 160 /*
 161  * Red-black tree helpers for vm fictitious range management.
 162  */
 163 static inline int
 164 vm_phys_fictitious_in_range(struct vm_phys_fictitious_seg *p,
 165     struct vm_phys_fictitious_seg *range)
 166 {
 167
 168         KASSERT(range->start != 0 && range->end != 0,
 169             ("Invalid range passed on search for vm_fictitious page"));
 170         if (p->start >= range->end)
 171                 return (1);
 172         if (p->start < range->start)
 173                 return (-1);
 174
 175         return (0);
 176 }
 177
 178 static int
 179 vm_phys_fictitious_cmp(struct vm_phys_fictitious_seg *p1,
 180     struct vm_phys_fictitious_seg *p2)
 181 {
 182
 183         /* Check if this is a search for a page */
 184         if (p1->end == 0)
 185                 return (vm_phys_fictitious_in_range(p1, p2));
 186
 187         KASSERT(p2->end != 0,
 188     ("Invalid range passed as second parameter to vm fictitious comparison"));
 189
 190         /* Searching to add a new range */
 191         if (p1->end <= p2->start)
 192                 return (-1);
 193         if (p1->start >= p2->end)
 194                 return (1);
 195
 196         panic("Trying to add overlapping vm fictitious ranges:\n"
 197             "[%#jx:%#jx] and [%#jx:%#jx]", (uintmax_t)p1->start,
 198             (uintmax_t)p1->end, (uintmax_t)p2->start, (uintmax_t)p2->end);
 199 }
 200
 201 int
 202 vm_phys_domain_match(int prefer, vm_paddr_t low, vm_paddr_t high)
 203 {
 204 #ifdef NUMA
 205         domainset_t mask;
 206         int i;
 207
 208         if (vm_ndomains == 1 || mem_affinity == NULL)
 209                 return (0);
 210
 211         DOMAINSET_ZERO(&mask);
 212         /*
 213          * Check for any memory that overlaps low, high.
 214          */
 215         for (i = 0; mem_affinity[i].end != 0; i++)
 216                 if (mem_affinity[i].start <= high &&
 217                     mem_affinity[i].end >= low)
 218                         DOMAINSET_SET(mem_affinity[i].domain, &mask);
 219         if (prefer != -1 && DOMAINSET_ISSET(prefer, &mask))
 220                 return (prefer);
 221         if (DOMAINSET_EMPTY(&mask))
 222                 panic("vm_phys_domain_match:  Impossible constraint");
 223         return (DOMAINSET_FFS(&mask) - 1);
 224 #else
 225         return (0);
 226 #endif
 227 }
 228
 229 /*
 230  * Outputs the state of the physical memory allocator, specifically,
 231  * the amount of physical memory in each free list.
 232  */
 233 static int
 234 sysctl_vm_phys_free(SYSCTL_HANDLER_ARGS)
 235 {
 236         struct sbuf sbuf;
 237         struct vm_freelist *fl;
 238         int dom, error, flind, oind, pind;
 239
 240         error = sysctl_wire_old_buffer(req, 0);
 241         if (error != 0)
 242                 return (error);
 243         sbuf_new_for_sysctl(&sbuf, NULL, 128 * vm_ndomains, req);
 244         for (dom = 0; dom < vm_ndomains; dom++) {
 245                 sbuf_printf(&sbuf,"\nDOMAIN %d:\n", dom);
 246                 for (flind = 0; flind < vm_nfreelists; flind++) {
 247                         sbuf_printf(&sbuf, "\nFREE LIST %d:\n"
 248                             "\n  ORDER (SIZE)  |  NUMBER"
 249                             "\n              ", flind);
 250                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
 251                                 sbuf_printf(&sbuf, "  |  POOL %d", pind);
 252                         sbuf_printf(&sbuf, "\n--            ");
 253                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
 254                                 sbuf_printf(&sbuf, "-- --      ");
 255                         sbuf_printf(&sbuf, "--\n");
 256                         for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
 257                                 sbuf_printf(&sbuf, "  %2d (%6dK)", oind,
 258                                     1 << (PAGE_SHIFT - 10 + oind));
 259                                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 260                                 fl = vm_phys_free_queues[dom][flind][pind];
 261                                         sbuf_printf(&sbuf, "  |  %6d",
 262                                             fl[oind].lcnt);
 263                                 }
 264                                 sbuf_printf(&sbuf, "\n");
 265                         }
 266                 }
 267         }
 268         error = sbuf_finish(&sbuf);
 269         sbuf_delete(&sbuf);
 270         return (error);
 271 }
 272
 273 /*
 274  * Outputs the set of physical memory segments.
 275  */
 276 static int
 277 sysctl_vm_phys_segs(SYSCTL_HANDLER_ARGS)
 278 {
 279         struct sbuf sbuf;
 280         struct vm_phys_seg *seg;
 281         int error, segind;
 282
 283         error = sysctl_wire_old_buffer(req, 0);
 284         if (error != 0)
 285                 return (error);
 286         sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
 287         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 288                 sbuf_printf(&sbuf, "\nSEGMENT %d:\n\n", segind);
 289                 seg = &vm_phys_segs[segind];
 290                 sbuf_printf(&sbuf, "start:     %#jx\n",
 291                     (uintmax_t)seg->start);
 292                 sbuf_printf(&sbuf, "end:       %#jx\n",
 293                     (uintmax_t)seg->end);
 294                 sbuf_printf(&sbuf, "domain:    %d\n", seg->domain);
 295                 sbuf_printf(&sbuf, "free list: %p\n", seg->free_queues);
 296         }
 297         error = sbuf_finish(&sbuf);
 298         sbuf_delete(&sbuf);
 299         return (error);
 300 }
 301
 302 /*
 303  * Return affinity, or -1 if there's no affinity information.
 304  */
 305 int
 306 vm_phys_mem_affinity(int f, int t)
 307 {
 308
 309 #ifdef NUMA
 310         if (mem_locality == NULL)
 311                 return (-1);
 312         if (f >= vm_ndomains || t >= vm_ndomains)
 313                 return (-1);
 314         return (mem_locality[f * vm_ndomains + t]);
 315 #else
 316         return (-1);
 317 #endif
 318 }
 319
 320 #ifdef NUMA
 321 /*
 322  * Outputs the VM locality table.
 323  */
 324 static int
 325 sysctl_vm_phys_locality(SYSCTL_HANDLER_ARGS)
 326 {
 327         struct sbuf sbuf;
 328         int error, i, j;
 329
 330         error = sysctl_wire_old_buffer(req, 0);
 331         if (error != 0)
 332                 return (error);
 333         sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
 334
 335         sbuf_printf(&sbuf, "\n");
 336
 337         for (i = 0; i < vm_ndomains; i++) {
 338                 sbuf_printf(&sbuf, "%d: ", i);
 339                 for (j = 0; j < vm_ndomains; j++) {
 340                         sbuf_printf(&sbuf, "%d ", vm_phys_mem_affinity(i, j));
 341                 }
 342                 sbuf_printf(&sbuf, "\n");
 343         }
 344         error = sbuf_finish(&sbuf);
 345         sbuf_delete(&sbuf);
 346         return (error);
 347 }
 348 #endif
 349
 350 static void
 351 vm_freelist_add(struct vm_freelist *fl, vm_page_t m, int order, int tail)
 352 {
 353
 354         m->order = order;
 355         if (tail)
 356                 TAILQ_INSERT_TAIL(&fl[order].pl, m, plinks.q);
 357         else
 358                 TAILQ_INSERT_HEAD(&fl[order].pl, m, plinks.q);
 359         fl[order].lcnt++;
 360 }
 361
 362 static void
 363 vm_freelist_rem(struct vm_freelist *fl, vm_page_t m, int order)
 364 {
 365
 366         TAILQ_REMOVE(&fl[order].pl, m, plinks.q);
 367         fl[order].lcnt--;
 368         m->order = VM_NFREEORDER;
 369 }
 370
 371 /*
 372  * Create a physical memory segment.
 373  */
 374 static void
 375 _vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int domain)
 376 {
 377         struct vm_phys_seg *seg;
 378
 379         KASSERT(vm_phys_nsegs < VM_PHYSSEG_MAX,
 380             ("vm_phys_create_seg: increase VM_PHYSSEG_MAX"));
 381         KASSERT(domain >= 0 && domain < vm_ndomains,
 382             ("vm_phys_create_seg: invalid domain provided"));
 383         seg = &vm_phys_segs[vm_phys_nsegs++];
 384         while (seg > vm_phys_segs && (seg - 1)->start >= end) {
 385                 *seg = *(seg - 1);
 386                 seg--;
 387         }
 388         seg->start = start;
 389         seg->end = end;
 390         seg->domain = domain;
 391 }
 392
 393 static void
 394 vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end)
 395 {
 396 #ifdef NUMA
 397         int i;
 398
 399         if (mem_affinity == NULL) {
 400                 _vm_phys_create_seg(start, end, 0);
 401                 return;
 402         }
 403
 404         for (i = 0;; i++) {
 405                 if (mem_affinity[i].end == 0)
 406                         panic("Reached end of affinity info");
 407                 if (mem_affinity[i].end <= start)
 408                         continue;
 409                 if (mem_affinity[i].start > start)
 410                         panic("No affinity info for start %jx",
 411                             (uintmax_t)start);
 412                 if (mem_affinity[i].end >= end) {
 413                         _vm_phys_create_seg(start, end,
 414                             mem_affinity[i].domain);
 415                         break;
 416                 }
 417                 _vm_phys_create_seg(start, mem_affinity[i].end,
 418                     mem_affinity[i].domain);
 419                 start = mem_affinity[i].end;
 420         }
 421 #else
 422         _vm_phys_create_seg(start, end, 0);
 423 #endif
 424 }
 425
 426 /*
 427  * Add a physical memory segment.
 428  */
 429 void
 430 vm_phys_add_seg(vm_paddr_t start, vm_paddr_t end)
 431 {
 432         vm_paddr_t paddr;
 433
 434         KASSERT((start & PAGE_MASK) == 0,
 435             ("vm_phys_define_seg: start is not page aligned"));
 436         KASSERT((end & PAGE_MASK) == 0,
 437             ("vm_phys_define_seg: end is not page aligned"));
 438
 439         /*
 440          * Split the physical memory segment if it spans two or more free
 441          * list boundaries.
 442          */
 443         paddr = start;
 444 #ifdef  VM_FREELIST_ISADMA
 445         if (paddr < VM_ISADMA_BOUNDARY && end > VM_ISADMA_BOUNDARY) {
 446                 vm_phys_create_seg(paddr, VM_ISADMA_BOUNDARY);
 447                 paddr = VM_ISADMA_BOUNDARY;
 448         }
 449 #endif
 450 #ifdef  VM_FREELIST_LOWMEM
 451         if (paddr < VM_LOWMEM_BOUNDARY && end > VM_LOWMEM_BOUNDARY) {
 452                 vm_phys_create_seg(paddr, VM_LOWMEM_BOUNDARY);
 453                 paddr = VM_LOWMEM_BOUNDARY;
 454         }
 455 #endif
 456 #ifdef  VM_FREELIST_DMA32
 457         if (paddr < VM_DMA32_BOUNDARY && end > VM_DMA32_BOUNDARY) {
 458                 vm_phys_create_seg(paddr, VM_DMA32_BOUNDARY);
 459                 paddr = VM_DMA32_BOUNDARY;
 460         }
 461 #endif
 462         vm_phys_create_seg(paddr, end);
 463 }
 464
 465 /*
 466  * Initialize the physical memory allocator.
 467  *
 468  * Requires that vm_page_array is initialized!
 469  */
 470 void
 471 vm_phys_init(void)
 472 {
 473         struct vm_freelist *fl;
 474         struct vm_phys_seg *seg;
 475         u_long npages;
 476         int dom, flind, freelist, oind, pind, segind;
 477
 478         /*
 479          * Compute the number of free lists, and generate the mapping from the
 480          * manifest constants VM_FREELIST_* to the free list indices.
 481          *
 482          * Initially, the entries of vm_freelist_to_flind[] are set to either
 483          * 0 or 1 to indicate which free lists should be created.
 484          */
 485         npages = 0;
 486         for (segind = vm_phys_nsegs - 1; segind >= 0; segind--) {
 487                 seg = &vm_phys_segs[segind];
 488 #ifdef  VM_FREELIST_ISADMA
 489                 if (seg->end <= VM_ISADMA_BOUNDARY)
 490                         vm_freelist_to_flind[VM_FREELIST_ISADMA] = 1;
 491                 else
 492 #endif
 493 #ifdef  VM_FREELIST_LOWMEM
 494                 if (seg->end <= VM_LOWMEM_BOUNDARY)
 495                         vm_freelist_to_flind[VM_FREELIST_LOWMEM] = 1;
 496                 else
 497 #endif
 498 #ifdef  VM_FREELIST_DMA32
 499                 if (
 500 #ifdef  VM_DMA32_NPAGES_THRESHOLD
 501                     /*
 502                      * Create the DMA32 free list only if the amount of
 503                      * physical memory above physical address 4G exceeds the
 504                      * given threshold.
 505                      */
 506                     npages > VM_DMA32_NPAGES_THRESHOLD &&
 507 #endif
 508                     seg->end <= VM_DMA32_BOUNDARY)
 509                         vm_freelist_to_flind[VM_FREELIST_DMA32] = 1;
 510                 else
 511 #endif
 512                 {
 513                         npages += atop(seg->end - seg->start);
 514                         vm_freelist_to_flind[VM_FREELIST_DEFAULT] = 1;
 515                 }
 516         }
 517         /* Change each entry into a running total of the free lists. */
 518         for (freelist = 1; freelist < VM_NFREELIST; freelist++) {
 519                 vm_freelist_to_flind[freelist] +=
 520                     vm_freelist_to_flind[freelist - 1];
 521         }
 522         vm_nfreelists = vm_freelist_to_flind[VM_NFREELIST - 1];
 523         KASSERT(vm_nfreelists > 0, ("vm_phys_init: no free lists"));
 524         /* Change each entry into a free list index. */
 525         for (freelist = 0; freelist < VM_NFREELIST; freelist++)
 526                 vm_freelist_to_flind[freelist]--;
 527
 528         /*
 529          * Initialize the first_page and free_queues fields of each physical
 530          * memory segment.
 531          */
 532 #ifdef VM_PHYSSEG_SPARSE
 533         npages = 0;
 534 #endif
 535         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 536                 seg = &vm_phys_segs[segind];
 537 #ifdef VM_PHYSSEG_SPARSE
 538                 seg->first_page = &vm_page_array[npages];
 539                 npages += atop(seg->end - seg->start);
 540 #else
 541                 seg->first_page = PHYS_TO_VM_PAGE(seg->start);
 542 #endif
 543 #ifdef  VM_FREELIST_ISADMA
 544                 if (seg->end <= VM_ISADMA_BOUNDARY) {
 545                         flind = vm_freelist_to_flind[VM_FREELIST_ISADMA];
 546                         KASSERT(flind >= 0,
 547                             ("vm_phys_init: ISADMA flind < 0"));
 548                 } else
 549 #endif
 550 #ifdef  VM_FREELIST_LOWMEM
 551                 if (seg->end <= VM_LOWMEM_BOUNDARY) {
 552                         flind = vm_freelist_to_flind[VM_FREELIST_LOWMEM];
 553                         KASSERT(flind >= 0,
 554                             ("vm_phys_init: LOWMEM flind < 0"));
 555                 } else
 556 #endif
 557 #ifdef  VM_FREELIST_DMA32
 558                 if (seg->end <= VM_DMA32_BOUNDARY) {
 559                         flind = vm_freelist_to_flind[VM_FREELIST_DMA32];
 560                         KASSERT(flind >= 0,
 561                             ("vm_phys_init: DMA32 flind < 0"));
 562                 } else
 563 #endif
 564                 {
 565                         flind = vm_freelist_to_flind[VM_FREELIST_DEFAULT];
 566                         KASSERT(flind >= 0,
 567                             ("vm_phys_init: DEFAULT flind < 0"));
 568                 }
 569                 seg->free_queues = &vm_phys_free_queues[seg->domain][flind];
 570         }
 571
 572         /*
 573          * Initialize the free queues.
 574          */
 575         for (dom = 0; dom < vm_ndomains; dom++) {
 576                 for (flind = 0; flind < vm_nfreelists; flind++) {
 577                         for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 578                                 fl = vm_phys_free_queues[dom][flind][pind];
 579                                 for (oind = 0; oind < VM_NFREEORDER; oind++)
 580                                         TAILQ_INIT(&fl[oind].pl);
 581                         }
 582                 }
 583         }
 584
 585         rw_init(&vm_phys_fictitious_reg_lock, "vmfctr");
 586 }
 587
 588 /*
 589  * Split a contiguous, power of two-sized set of physical pages.
 590  */
 591 static __inline void
 592 vm_phys_split_pages(vm_page_t m, int oind, struct vm_freelist *fl, int order)
 593 {
 594         vm_page_t m_buddy;
 595
 596         while (oind > order) {
 597                 oind--;
 598                 m_buddy = &m[1 << oind];
 599                 KASSERT(m_buddy->order == VM_NFREEORDER,
 600                     ("vm_phys_split_pages: page %p has unexpected order %d",
 601                     m_buddy, m_buddy->order));
 602                 vm_freelist_add(fl, m_buddy, oind, 0);
 603         }
 604 }
 605
 606 /*
 607  * Allocate a contiguous, power of two-sized set of physical pages
 608  * from the free lists.
 609  *
 610  * The free page queues must be locked.
 611  */
 612 vm_page_t
 613 vm_phys_alloc_pages(int domain, int pool, int order)
 614 {
 615         vm_page_t m;
 616         int freelist;
 617
 618         for (freelist = 0; freelist < VM_NFREELIST; freelist++) {
 619                 m = vm_phys_alloc_freelist_pages(domain, freelist, pool, order);
 620                 if (m != NULL)
 621                         return (m);
 622         }
 623         return (NULL);
 624 }
 625
 626 /*
 627  * Allocate a contiguous, power of two-sized set of physical pages from the
 628  * specified free list.  The free list must be specified using one of the
 629  * manifest constants VM_FREELIST_*.
 630  *
 631  * The free page queues must be locked.
 632  */
 633 vm_page_t
 634 vm_phys_alloc_freelist_pages(int domain, int freelist, int pool, int order)
 635 {
 636         struct vm_freelist *alt, *fl;
 637         vm_page_t m;
 638         int oind, pind, flind;
 639
 640         KASSERT(domain >= 0 && domain < vm_ndomains,
 641             ("vm_phys_alloc_freelist_pages: domain %d is out of range",
 642             domain));
 643         KASSERT(freelist < VM_NFREELIST,
 644             ("vm_phys_alloc_freelist_pages: freelist %d is out of range",
 645             freelist));
 646         KASSERT(pool < VM_NFREEPOOL,
 647             ("vm_phys_alloc_freelist_pages: pool %d is out of range", pool));
 648         KASSERT(order < VM_NFREEORDER,
 649             ("vm_phys_alloc_freelist_pages: order %d is out of range", order));
 650
 651         flind = vm_freelist_to_flind[freelist];
 652         /* Check if freelist is present */
 653         if (flind < 0)
 654                 return (NULL);
 655
 656         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
 657         fl = &vm_phys_free_queues[domain][flind][pool][0];
 658         for (oind = order; oind < VM_NFREEORDER; oind++) {
 659                 m = TAILQ_FIRST(&fl[oind].pl);
 660                 if (m != NULL) {
 661                         vm_freelist_rem(fl, m, oind);
 662                         vm_phys_split_pages(m, oind, fl, order);
 663                         return (m);
 664                 }
 665         }
 666
 667         /*
 668          * The given pool was empty.  Find the largest
 669          * contiguous, power-of-two-sized set of pages in any
 670          * pool.  Transfer these pages to the given pool, and
 671          * use them to satisfy the allocation.
 672          */
 673         for (oind = VM_NFREEORDER - 1; oind >= order; oind--) {
 674                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 675                         alt = &vm_phys_free_queues[domain][flind][pind][0];
 676                         m = TAILQ_FIRST(&alt[oind].pl);
 677                         if (m != NULL) {
 678                                 vm_freelist_rem(alt, m, oind);
 679                                 vm_phys_set_pool(pool, m, oind);
 680                                 vm_phys_split_pages(m, oind, fl, order);
 681                                 return (m);
 682                         }
 683                 }
 684         }
 685         return (NULL);
 686 }
 687
 688 /*
 689  * Find the vm_page corresponding to the given physical address.
 690  */
 691 vm_page_t
 692 vm_phys_paddr_to_vm_page(vm_paddr_t pa)
 693 {
 694         struct vm_phys_seg *seg;
 695         int segind;
 696
 697         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 698                 seg = &vm_phys_segs[segind];
 699                 if (pa >= seg->start && pa < seg->end)
 700                         return (&seg->first_page[atop(pa - seg->start)]);
 701         }
 702         return (NULL);
 703 }
 704
 705 vm_page_t
 706 vm_phys_fictitious_to_vm_page(vm_paddr_t pa)
 707 {
 708         struct vm_phys_fictitious_seg tmp, *seg;
 709         vm_page_t m;
 710
 711         m = NULL;
 712         tmp.start = pa;
 713         tmp.end = 0;
 714
 715         rw_rlock(&vm_phys_fictitious_reg_lock);
 716         seg = RB_FIND(fict_tree, &vm_phys_fictitious_tree, &tmp);
 717         rw_runlock(&vm_phys_fictitious_reg_lock);
 718         if (seg == NULL)
 719                 return (NULL);
 720
 721         m = &seg->first_page[atop(pa - seg->start)];
 722         KASSERT((m->flags & PG_FICTITIOUS) != 0, ("%p not fictitious", m));
 723
 724         return (m);
 725 }
 726
 727 static inline void
 728 vm_phys_fictitious_init_range(vm_page_t range, vm_paddr_t start,
 729     long page_count, vm_memattr_t memattr)
 730 {
 731         long i;
 732
 733         bzero(range, page_count * sizeof(*range));
 734         for (i = 0; i < page_count; i++) {
 735                 vm_page_initfake(&range[i], start + PAGE_SIZE * i, memattr);
 736                 range[i].oflags &= ~VPO_UNMANAGED;
 737                 range[i].busy_lock = VPB_UNBUSIED;
 738         }
 739 }
 740
 741 int
 742 vm_phys_fictitious_reg_range(vm_paddr_t start, vm_paddr_t end,
 743     vm_memattr_t memattr)
 744 {
 745         struct vm_phys_fictitious_seg *seg;
 746         vm_page_t fp;
 747         long page_count;
 748 #ifdef VM_PHYSSEG_DENSE
 749         long pi, pe;
 750         long dpage_count;
 751 #endif
 752
 753         KASSERT(start < end,
 754             ("Start of segment isn't less than end (start: %jx end: %jx)",
 755             (uintmax_t)start, (uintmax_t)end));
 756
 757         page_count = (end - start) / PAGE_SIZE;
 758
 759 #ifdef VM_PHYSSEG_DENSE
 760         pi = atop(start);
 761         pe = atop(end);
 762         if (pi >= first_page && (pi - first_page) < vm_page_array_size) {
 763                 fp = &vm_page_array[pi - first_page];
 764                 if ((pe - first_page) > vm_page_array_size) {
 765                         /*
 766                          * We have a segment that starts inside
 767                          * of vm_page_array, but ends outside of it.
 768                          *
 769                          * Use vm_page_array pages for those that are
 770                          * inside of the vm_page_array range, and
 771                          * allocate the remaining ones.
 772                          */
 773                         dpage_count = vm_page_array_size - (pi - first_page);
 774                         vm_phys_fictitious_init_range(fp, start, dpage_count,
 775                             memattr);
 776                         page_count -= dpage_count;
 777                         start += ptoa(dpage_count);
 778                         goto alloc;
 779                 }
 780                 /*
 781                  * We can allocate the full range from vm_page_array,
 782                  * so there's no need to register the range in the tree.
 783                  */
 784                 vm_phys_fictitious_init_range(fp, start, page_count, memattr);
 785                 return (0);
 786         } else if (pe > first_page && (pe - first_page) < vm_page_array_size) {
 787                 /*
 788                  * We have a segment that ends inside of vm_page_array,
 789                  * but starts outside of it.
 790                  */
 791                 fp = &vm_page_array[0];
 792                 dpage_count = pe - first_page;
 793                 vm_phys_fictitious_init_range(fp, ptoa(first_page), dpage_count,
 794                     memattr);
 795                 end -= ptoa(dpage_count);
 796                 page_count -= dpage_count;
 797                 goto alloc;
 798         } else if (pi < first_page && pe > (first_page + vm_page_array_size)) {
 799                 /*
 800                  * Trying to register a fictitious range that expands before
 801                  * and after vm_page_array.
 802                  */
 803                 return (EINVAL);
 804         } else {
 805 alloc:
 806 #endif
 807                 fp = malloc(page_count * sizeof(struct vm_page), M_FICT_PAGES,
 808                     M_WAITOK);
 809 #ifdef VM_PHYSSEG_DENSE
 810         }
 811 #endif
 812         vm_phys_fictitious_init_range(fp, start, page_count, memattr);
 813
 814         seg = malloc(sizeof(*seg), M_FICT_PAGES, M_WAITOK | M_ZERO);
 815         seg->start = start;
 816         seg->end = end;
 817         seg->first_page = fp;
 818
 819         rw_wlock(&vm_phys_fictitious_reg_lock);
 820         RB_INSERT(fict_tree, &vm_phys_fictitious_tree, seg);
 821         rw_wunlock(&vm_phys_fictitious_reg_lock);
 822
 823         return (0);
 824 }
 825
 826 void
 827 vm_phys_fictitious_unreg_range(vm_paddr_t start, vm_paddr_t end)
 828 {
 829         struct vm_phys_fictitious_seg *seg, tmp;
 830 #ifdef VM_PHYSSEG_DENSE
 831         long pi, pe;
 832 #endif
 833
 834         KASSERT(start < end,
 835             ("Start of segment isn't less than end (start: %jx end: %jx)",
 836             (uintmax_t)start, (uintmax_t)end));
 837
 838 #ifdef VM_PHYSSEG_DENSE
 839         pi = atop(start);
 840         pe = atop(end);
 841         if (pi >= first_page && (pi - first_page) < vm_page_array_size) {
 842                 if ((pe - first_page) <= vm_page_array_size) {
 843                         /*
 844                          * This segment was allocated using vm_page_array
 845                          * only, there's nothing to do since those pages
 846                          * were never added to the tree.
 847                          */
 848                         return;
 849                 }
 850                 /*
 851                  * We have a segment that starts inside
 852                  * of vm_page_array, but ends outside of it.
 853                  *
 854                  * Calculate how many pages were added to the
 855                  * tree and free them.
 856                  */
 857                 start = ptoa(first_page + vm_page_array_size);
 858         } else if (pe > first_page && (pe - first_page) < vm_page_array_size) {
 859                 /*
 860                  * We have a segment that ends inside of vm_page_array,
 861                  * but starts outside of it.
 862                  */
 863                 end = ptoa(first_page);
 864         } else if (pi < first_page && pe > (first_page + vm_page_array_size)) {
 865                 /* Since it's not possible to register such a range, panic. */
 866                 panic(
 867                     "Unregistering not registered fictitious range [%#jx:%#jx]",
 868                     (uintmax_t)start, (uintmax_t)end);
 869         }
 870 #endif
 871         tmp.start = start;
 872         tmp.end = 0;
 873
 874         rw_wlock(&vm_phys_fictitious_reg_lock);
 875         seg = RB_FIND(fict_tree, &vm_phys_fictitious_tree, &tmp);
 876         if (seg->start != start || seg->end != end) {
 877                 rw_wunlock(&vm_phys_fictitious_reg_lock);
 878                 panic(
 879                     "Unregistering not registered fictitious range [%#jx:%#jx]",
 880                     (uintmax_t)start, (uintmax_t)end);
 881         }
 882         RB_REMOVE(fict_tree, &vm_phys_fictitious_tree, seg);
 883         rw_wunlock(&vm_phys_fictitious_reg_lock);
 884         free(seg->first_page, M_FICT_PAGES);
 885         free(seg, M_FICT_PAGES);
 886 }
 887
 888 /*
 889  * Free a contiguous, power of two-sized set of physical pages.
 890  *
 891  * The free page queues must be locked.
 892  */
 893 void
 894 vm_phys_free_pages(vm_page_t m, int order)
 895 {
 896         struct vm_freelist *fl;
 897         struct vm_phys_seg *seg;
 898         vm_paddr_t pa;
 899         vm_page_t m_buddy;
 900
 901         KASSERT(m->order == VM_NFREEORDER,
 902             ("vm_phys_free_pages: page %p has unexpected order %d",
 903             m, m->order));
 904         KASSERT(m->pool < VM_NFREEPOOL,
 905             ("vm_phys_free_pages: page %p has unexpected pool %d",
 906             m, m->pool));
 907         KASSERT(order < VM_NFREEORDER,
 908             ("vm_phys_free_pages: order %d is out of range", order));
 909         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
 910         seg = &vm_phys_segs[m->segind];
 911         if (order < VM_NFREEORDER - 1) {
 912                 pa = VM_PAGE_TO_PHYS(m);
 913                 do {
 914                         pa ^= ((vm_paddr_t)1 << (PAGE_SHIFT + order));
 915                         if (pa < seg->start || pa >= seg->end)
 916                                 break;
 917                         m_buddy = &seg->first_page[atop(pa - seg->start)];
 918                         if (m_buddy->order != order)
 919                                 break;
 920                         fl = (*seg->free_queues)[m_buddy->pool];
 921                         vm_freelist_rem(fl, m_buddy, order);
 922                         if (m_buddy->pool != m->pool)
 923                                 vm_phys_set_pool(m->pool, m_buddy, order);
 924                         order++;
 925                         pa &= ~(((vm_paddr_t)1 << (PAGE_SHIFT + order)) - 1);
 926                         m = &seg->first_page[atop(pa - seg->start)];
 927                 } while (order < VM_NFREEORDER - 1);
 928         }
 929         fl = (*seg->free_queues)[m->pool];
 930         vm_freelist_add(fl, m, order, 1);
 931 }
 932
 933 /*
 934  * Free a contiguous, arbitrarily sized set of physical pages.
 935  *
 936  * The free page queues must be locked.
 937  */
 938 void
 939 vm_phys_free_contig(vm_page_t m, u_long npages)
 940 {
 941         u_int n;
 942         int order;
 943
 944         /*
 945          * Avoid unnecessary coalescing by freeing the pages in the largest
 946          * possible power-of-two-sized subsets.
 947          */
 948         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
 949         for (;; npages -= n) {
 950                 /*
 951                  * Unsigned "min" is used here so that "order" is assigned
 952                  * "VM_NFREEORDER - 1" when "m"'s physical address is zero
 953                  * or the low-order bits of its physical address are zero
 954                  * because the size of a physical address exceeds the size of
 955                  * a long.
 956                  */
 957                 order = min(ffsl(VM_PAGE_TO_PHYS(m) >> PAGE_SHIFT) - 1,
 958                     VM_NFREEORDER - 1);
 959                 n = 1 << order;
 960                 if (npages < n)
 961                         break;
 962                 vm_phys_free_pages(m, order);
 963                 m += n;
 964         }
 965         /* The residual "npages" is less than "1 << (VM_NFREEORDER - 1)". */
 966         for (; npages > 0; npages -= n) {
 967                 order = flsl(npages) - 1;
 968                 n = 1 << order;
 969                 vm_phys_free_pages(m, order);
 970                 m += n;
 971         }
 972 }
 973
 974 /*
 975  * Scan physical memory between the specified addresses "low" and "high" for a
 976  * run of contiguous physical pages that satisfy the specified conditions, and
 977  * return the lowest page in the run.  The specified "alignment" determines
 978  * the alignment of the lowest physical page in the run.  If the specified
 979  * "boundary" is non-zero, then the run of physical pages cannot span a
 980  * physical address that is a multiple of "boundary".
 981  *
 982  * "npages" must be greater than zero.  Both "alignment" and "boundary" must
 983  * be a power of two.
 984  */
 985 vm_page_t
 986 vm_phys_scan_contig(int domain, u_long npages, vm_paddr_t low, vm_paddr_t high,
 987     u_long alignment, vm_paddr_t boundary, int options)
 988 {
 989         vm_paddr_t pa_end;
 990         vm_page_t m_end, m_run, m_start;
 991         struct vm_phys_seg *seg;
 992         int segind;
 993
 994         KASSERT(npages > 0, ("npages is 0"));
 995         KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
 996         KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
 997         if (low >= high)
 998                 return (NULL);
 999         for (segind = 0; segind < vm_phys_nsegs; segind++) {
1000                 seg = &vm_phys_segs[segind];
1001                 if (seg->domain != domain)
1002                         continue;
1003                 if (seg->start >= high)
1004                         break;
1005                 if (low >= seg->end)
1006                         continue;
1007                 if (low <= seg->start)
1008                         m_start = seg->first_page;
1009                 else
1010                         m_start = &seg->first_page[atop(low - seg->start)];
1011                 if (high < seg->end)
1012                         pa_end = high;
1013                 else
1014                         pa_end = seg->end;
1015                 if (pa_end - VM_PAGE_TO_PHYS(m_start) < ptoa(npages))
1016                         continue;
1017                 m_end = &seg->first_page[atop(pa_end - seg->start)];
1018                 m_run = vm_page_scan_contig(npages, m_start, m_end,
1019                     alignment, boundary, options);
1020                 if (m_run != NULL)
1021                         return (m_run);
1022         }
1023         return (NULL);
1024 }
1025
1026 /*
1027  * Set the pool for a contiguous, power of two-sized set of physical pages.
1028  */
1029 void
1030 vm_phys_set_pool(int pool, vm_page_t m, int order)
1031 {
1032         vm_page_t m_tmp;
1033
1034         for (m_tmp = m; m_tmp < &m[1 << order]; m_tmp++)
1035                 m_tmp->pool = pool;
1036 }
1037
1038 /*
1039  * Search for the given physical page "m" in the free lists.  If the search
1040  * succeeds, remove "m" from the free lists and return TRUE.  Otherwise, return
1041  * FALSE, indicating that "m" is not in the free lists.
1042  *
1043  * The free page queues must be locked.
1044  */
1045 boolean_t
1046 vm_phys_unfree_page(vm_page_t m)
1047 {
1048         struct vm_freelist *fl;
1049         struct vm_phys_seg *seg;
1050         vm_paddr_t pa, pa_half;
1051         vm_page_t m_set, m_tmp;
1052         int order;
1053
1054         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
1055
1056         /*
1057          * First, find the contiguous, power of two-sized set of free
1058          * physical pages containing the given physical page "m" and
1059          * assign it to "m_set".
1060          */
1061         seg = &vm_phys_segs[m->segind];
1062         for (m_set = m, order = 0; m_set->order == VM_NFREEORDER &&
1063             order < VM_NFREEORDER - 1; ) {
1064                 order++;
1065                 pa = m->phys_addr & (~(vm_paddr_t)0 << (PAGE_SHIFT + order));
1066                 if (pa >= seg->start)
1067                         m_set = &seg->first_page[atop(pa - seg->start)];
1068                 else
1069                         return (FALSE);
1070         }
1071         if (m_set->order < order)
1072                 return (FALSE);
1073         if (m_set->order == VM_NFREEORDER)
1074                 return (FALSE);
1075         KASSERT(m_set->order < VM_NFREEORDER,
1076             ("vm_phys_unfree_page: page %p has unexpected order %d",
1077             m_set, m_set->order));
1078
1079         /*
1080          * Next, remove "m_set" from the free lists.  Finally, extract
1081          * "m" from "m_set" using an iterative algorithm: While "m_set"
1082          * is larger than a page, shrink "m_set" by returning the half
1083          * of "m_set" that does not contain "m" to the free lists.
1084          */
1085         fl = (*seg->free_queues)[m_set->pool];
1086         order = m_set->order;
1087         vm_freelist_rem(fl, m_set, order);
1088         while (order > 0) {
1089                 order--;
1090                 pa_half = m_set->phys_addr ^ (1 << (PAGE_SHIFT + order));
1091                 if (m->phys_addr < pa_half)
1092                         m_tmp = &seg->first_page[atop(pa_half - seg->start)];
1093                 else {
1094                         m_tmp = m_set;
1095                         m_set = &seg->first_page[atop(pa_half - seg->start)];
1096                 }
1097                 vm_freelist_add(fl, m_tmp, order, 0);
1098         }
1099         KASSERT(m_set == m, ("vm_phys_unfree_page: fatal inconsistency"));
1100         return (TRUE);
1101 }
1102
1103 /*
1104  * Allocate a contiguous set of physical pages of the given size
1105  * "npages" from the free lists.  All of the physical pages must be at
1106  * or above the given physical address "low" and below the given
1107  * physical address "high".  The given value "alignment" determines the
1108  * alignment of the first physical page in the set.  If the given value
1109  * "boundary" is non-zero, then the set of physical pages cannot cross
1110  * any physical address boundary that is a multiple of that value.  Both
1111  * "alignment" and "boundary" must be a power of two.
1112  */
1113 vm_page_t
1114 vm_phys_alloc_contig(int domain, u_long npages, vm_paddr_t low, vm_paddr_t high,
1115     u_long alignment, vm_paddr_t boundary)
1116 {
1117         vm_paddr_t pa_end, pa_start;
1118         vm_page_t m_run;
1119         struct vm_phys_seg *seg;
1120         int segind;
1121
1122         KASSERT(npages > 0, ("npages is 0"));
1123         KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
1124         KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
1125         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
1126         if (low >= high)
1127                 return (NULL);
1128         m_run = NULL;
1129         for (segind = vm_phys_nsegs - 1; segind >= 0; segind--) {
1130                 seg = &vm_phys_segs[segind];
1131                 if (seg->start >= high || seg->domain != domain)
1132                         continue;
1133                 if (low >= seg->end)
1134                         break;
1135                 if (low <= seg->start)
1136                         pa_start = seg->start;
1137                 else
1138                         pa_start = low;
1139                 if (high < seg->end)
1140                         pa_end = high;
1141                 else
1142                         pa_end = seg->end;
1143                 if (pa_end - pa_start < ptoa(npages))
1144                         continue;
1145                 m_run = vm_phys_alloc_seg_contig(seg, npages, low, high,
1146                     alignment, boundary);
1147                 if (m_run != NULL)
1148                         break;
1149         }
1150         return (m_run);
1151 }
1152
1153 /*
1154  * Allocate a run of contiguous physical pages from the free list for the
1155  * specified segment.
1156  */
1157 static vm_page_t
1158 vm_phys_alloc_seg_contig(struct vm_phys_seg *seg, u_long npages,
1159     vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary)
1160 {
1161         struct vm_freelist *fl;
1162         vm_paddr_t pa, pa_end, size;
1163         vm_page_t m, m_ret;
1164         u_long npages_end;
1165         int oind, order, pind;
1166
1167         KASSERT(npages > 0, ("npages is 0"));
1168         KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
1169         KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
1170         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
1171         /* Compute the queue that is the best fit for npages. */
1172         for (order = 0; (1 << order) < npages; order++);
1173         /* Search for a run satisfying the specified conditions. */
1174         size = npages << PAGE_SHIFT;
1175         for (oind = min(order, VM_NFREEORDER - 1); oind < VM_NFREEORDER;
1176             oind++) {
1177                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
1178                         fl = (*seg->free_queues)[pind];
1179                         TAILQ_FOREACH(m_ret, &fl[oind].pl, plinks.q) {
1180                                 /*
1181                                  * Is the size of this allocation request
1182                                  * larger than the largest block size?
1183                                  */
1184                                 if (order >= VM_NFREEORDER) {
1185                                         /*
1186                                          * Determine if a sufficient number of
1187                                          * subsequent blocks to satisfy the
1188                                          * allocation request are free.
1189                                          */
1190                                         pa = VM_PAGE_TO_PHYS(m_ret);
1191                                         pa_end = pa + size;
1192                                         for (;;) {
1193                                                 pa += 1 << (PAGE_SHIFT +
1194                                                     VM_NFREEORDER - 1);
1195                                                 if (pa >= pa_end ||
1196                                                     pa < seg->start ||
1197                                                     pa >= seg->end)
1198                                                         break;
1199                                                 m = &seg->first_page[atop(pa -
1200                                                     seg->start)];
1201                                                 if (m->order != VM_NFREEORDER -
1202                                                     1)
1203                                                         break;
1204                                         }
1205                                         /* If not, go to the next block. */
1206                                         if (pa < pa_end)
1207                                                 continue;
1208                                 }
1209
1210                                 /*
1211                                  * Determine if the blocks are within the
1212                                  * given range, satisfy the given alignment,
1213                                  * and do not cross the given boundary.
1214                                  */
1215                                 pa = VM_PAGE_TO_PHYS(m_ret);
1216                                 pa_end = pa + size;
1217                                 if (pa >= low && pa_end <= high &&
1218                                     (pa & (alignment - 1)) == 0 &&
1219                                     rounddown2(pa ^ (pa_end - 1), boundary) == 0)
1220                                         goto done;
1221                         }
1222                 }
1223         }
1224         return (NULL);
1225 done:
1226         for (m = m_ret; m < &m_ret[npages]; m = &m[1 << oind]) {
1227                 fl = (*seg->free_queues)[m->pool];
1228                 vm_freelist_rem(fl, m, m->order);
1229         }
1230         if (m_ret->pool != VM_FREEPOOL_DEFAULT)
1231                 vm_phys_set_pool(VM_FREEPOOL_DEFAULT, m_ret, oind);
1232         fl = (*seg->free_queues)[m_ret->pool];
1233         vm_phys_split_pages(m_ret, oind, fl, order);
1234         /* Return excess pages to the free lists. */
1235         npages_end = roundup2(npages, 1 << imin(oind, order));
1236         if (npages < npages_end)
1237                 vm_phys_free_contig(&m_ret[npages], npages_end - npages);
1238         return (m_ret);
1239 }
1240
1241 #ifdef DDB
1242 /*
1243  * Show the number of physical pages in each of the free lists.
1244  */
1245 DB_SHOW_COMMAND(freepages, db_show_freepages)
1246 {
1247         struct vm_freelist *fl;
1248         int flind, oind, pind, dom;
1249
1250         for (dom = 0; dom < vm_ndomains; dom++) {
1251                 db_printf("DOMAIN: %d\n", dom);
1252                 for (flind = 0; flind < vm_nfreelists; flind++) {
1253                         db_printf("FREE LIST %d:\n"
1254                             "\n  ORDER (SIZE)  |  NUMBER"
1255                             "\n              ", flind);
1256                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
1257                                 db_printf("  |  POOL %d", pind);
1258                         db_printf("\n--            ");
1259                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
1260                                 db_printf("-- --      ");
1261                         db_printf("--\n");
1262                         for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
1263                                 db_printf("  %2.2d (%6.6dK)", oind,
1264                                     1 << (PAGE_SHIFT - 10 + oind));
1265                                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
1266                                 fl = vm_phys_free_queues[dom][flind][pind];
1267                                         db_printf("  |  %6.6d", fl[oind].lcnt);
1268                                 }
1269                                 db_printf("\n");
1270                         }
1271                         db_printf("\n");
1272                 }
1273                 db_printf("\n");
1274         }
1275 }
1276 #endif