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 #include <vm/vm_pagequeue.h>
  71
  72 _Static_assert(sizeof(long) * NBBY >= VM_PHYSSEG_MAX,
  73     "Too many physsegs.");
  74
  75 #ifdef NUMA
  76 struct mem_affinity __read_mostly *mem_affinity;
  77 int __read_mostly *mem_locality;
  78 #endif
  79
  80 int __read_mostly vm_ndomains = 1;
  81
  82 struct vm_phys_seg __read_mostly vm_phys_segs[VM_PHYSSEG_MAX];
  83 int __read_mostly vm_phys_nsegs;
  84
  85 struct vm_phys_fictitious_seg;
  86 static int vm_phys_fictitious_cmp(struct vm_phys_fictitious_seg *,
  87     struct vm_phys_fictitious_seg *);
  88
  89 RB_HEAD(fict_tree, vm_phys_fictitious_seg) vm_phys_fictitious_tree =
  90     RB_INITIALIZER(_vm_phys_fictitious_tree);
  91
  92 struct vm_phys_fictitious_seg {
  93         RB_ENTRY(vm_phys_fictitious_seg) node;
  94         /* Memory region data */
  95         vm_paddr_t      start;
  96         vm_paddr_t      end;
  97         vm_page_t       first_page;
  98 };
  99
 100 RB_GENERATE_STATIC(fict_tree, vm_phys_fictitious_seg, node,
 101     vm_phys_fictitious_cmp);
 102
 103 static struct rwlock_padalign vm_phys_fictitious_reg_lock;
 104 MALLOC_DEFINE(M_FICT_PAGES, "vm_fictitious", "Fictitious VM pages");
 105
 106 static struct vm_freelist __aligned(CACHE_LINE_SIZE)
 107     vm_phys_free_queues[MAXMEMDOM][VM_NFREELIST][VM_NFREEPOOL][VM_NFREEORDER];
 108
 109 static int __read_mostly vm_nfreelists;
 110
 111 /*
 112  * Provides the mapping from VM_FREELIST_* to free list indices (flind).
 113  */
 114 static int __read_mostly vm_freelist_to_flind[VM_NFREELIST];
 115
 116 CTASSERT(VM_FREELIST_DEFAULT == 0);
 117
 118 #ifdef VM_FREELIST_ISADMA
 119 #define VM_ISADMA_BOUNDARY      16777216
 120 #endif
 121 #ifdef VM_FREELIST_DMA32
 122 #define VM_DMA32_BOUNDARY       ((vm_paddr_t)1 << 32)
 123 #endif
 124
 125 /*
 126  * Enforce the assumptions made by vm_phys_add_seg() and vm_phys_init() about
 127  * the ordering of the free list boundaries.
 128  */
 129 #if defined(VM_ISADMA_BOUNDARY) && defined(VM_LOWMEM_BOUNDARY)
 130 CTASSERT(VM_ISADMA_BOUNDARY < VM_LOWMEM_BOUNDARY);
 131 #endif
 132 #if defined(VM_LOWMEM_BOUNDARY) && defined(VM_DMA32_BOUNDARY)
 133 CTASSERT(VM_LOWMEM_BOUNDARY < VM_DMA32_BOUNDARY);
 134 #endif
 135
 136 static int sysctl_vm_phys_free(SYSCTL_HANDLER_ARGS);
 137 SYSCTL_OID(_vm, OID_AUTO, phys_free, CTLTYPE_STRING | CTLFLAG_RD,
 138     NULL, 0, sysctl_vm_phys_free, "A", "Phys Free Info");
 139
 140 static int sysctl_vm_phys_segs(SYSCTL_HANDLER_ARGS);
 141 SYSCTL_OID(_vm, OID_AUTO, phys_segs, CTLTYPE_STRING | CTLFLAG_RD,
 142     NULL, 0, sysctl_vm_phys_segs, "A", "Phys Seg Info");
 143
 144 #ifdef NUMA
 145 static int sysctl_vm_phys_locality(SYSCTL_HANDLER_ARGS);
 146 SYSCTL_OID(_vm, OID_AUTO, phys_locality, CTLTYPE_STRING | CTLFLAG_RD,
 147     NULL, 0, sysctl_vm_phys_locality, "A", "Phys Locality Info");
 148 #endif
 149
 150 SYSCTL_INT(_vm, OID_AUTO, ndomains, CTLFLAG_RD,
 151     &vm_ndomains, 0, "Number of physical memory domains available.");
 152
 153 static vm_page_t vm_phys_alloc_seg_contig(struct vm_phys_seg *seg,
 154     u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment,
 155     vm_paddr_t boundary);
 156 static void _vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int domain);
 157 static void vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end);
 158 static void vm_phys_split_pages(vm_page_t m, int oind, struct vm_freelist *fl,
 159     int order);
 160
 161 /*
 162  * Red-black tree helpers for vm fictitious range management.
 163  */
 164 static inline int
 165 vm_phys_fictitious_in_range(struct vm_phys_fictitious_seg *p,
 166     struct vm_phys_fictitious_seg *range)
 167 {
 168
 169         KASSERT(range->start != 0 && range->end != 0,
 170             ("Invalid range passed on search for vm_fictitious page"));
 171         if (p->start >= range->end)
 172                 return (1);
 173         if (p->start < range->start)
 174                 return (-1);
 175
 176         return (0);
 177 }
 178
 179 static int
 180 vm_phys_fictitious_cmp(struct vm_phys_fictitious_seg *p1,
 181     struct vm_phys_fictitious_seg *p2)
 182 {
 183
 184         /* Check if this is a search for a page */
 185         if (p1->end == 0)
 186                 return (vm_phys_fictitious_in_range(p1, p2));
 187
 188         KASSERT(p2->end != 0,
 189     ("Invalid range passed as second parameter to vm fictitious comparison"));
 190
 191         /* Searching to add a new range */
 192         if (p1->end <= p2->start)
 193                 return (-1);
 194         if (p1->start >= p2->end)
 195                 return (1);
 196
 197         panic("Trying to add overlapping vm fictitious ranges:\n"
 198             "[%#jx:%#jx] and [%#jx:%#jx]", (uintmax_t)p1->start,
 199             (uintmax_t)p1->end, (uintmax_t)p2->start, (uintmax_t)p2->end);
 200 }
 201
 202 int
 203 vm_phys_domain_match(int prefer, vm_paddr_t low, vm_paddr_t high)
 204 {
 205 #ifdef NUMA
 206         domainset_t mask;
 207         int i;
 208
 209         if (vm_ndomains == 1 || mem_affinity == NULL)
 210                 return (0);
 211
 212         DOMAINSET_ZERO(&mask);
 213         /*
 214          * Check for any memory that overlaps low, high.
 215          */
 216         for (i = 0; mem_affinity[i].end != 0; i++)
 217                 if (mem_affinity[i].start <= high &&
 218                     mem_affinity[i].end >= low)
 219                         DOMAINSET_SET(mem_affinity[i].domain, &mask);
 220         if (prefer != -1 && DOMAINSET_ISSET(prefer, &mask))
 221                 return (prefer);
 222         if (DOMAINSET_EMPTY(&mask))
 223                 panic("vm_phys_domain_match:  Impossible constraint");
 224         return (DOMAINSET_FFS(&mask) - 1);
 225 #else
 226         return (0);
 227 #endif
 228 }
 229
 230 /*
 231  * Outputs the state of the physical memory allocator, specifically,
 232  * the amount of physical memory in each free list.
 233  */
 234 static int
 235 sysctl_vm_phys_free(SYSCTL_HANDLER_ARGS)
 236 {
 237         struct sbuf sbuf;
 238         struct vm_freelist *fl;
 239         int dom, error, flind, oind, pind;
 240
 241         error = sysctl_wire_old_buffer(req, 0);
 242         if (error != 0)
 243                 return (error);
 244         sbuf_new_for_sysctl(&sbuf, NULL, 128 * vm_ndomains, req);
 245         for (dom = 0; dom < vm_ndomains; dom++) {
 246                 sbuf_printf(&sbuf,"\nDOMAIN %d:\n", dom);
 247                 for (flind = 0; flind < vm_nfreelists; flind++) {
 248                         sbuf_printf(&sbuf, "\nFREE LIST %d:\n"
 249                             "\n  ORDER (SIZE)  |  NUMBER"
 250                             "\n              ", flind);
 251                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
 252                                 sbuf_printf(&sbuf, "  |  POOL %d", pind);
 253                         sbuf_printf(&sbuf, "\n--            ");
 254                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
 255                                 sbuf_printf(&sbuf, "-- --      ");
 256                         sbuf_printf(&sbuf, "--\n");
 257                         for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
 258                                 sbuf_printf(&sbuf, "  %2d (%6dK)", oind,
 259                                     1 << (PAGE_SHIFT - 10 + oind));
 260                                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 261                                 fl = vm_phys_free_queues[dom][flind][pind];
 262                                         sbuf_printf(&sbuf, "  |  %6d",
 263                                             fl[oind].lcnt);
 264                                 }
 265                                 sbuf_printf(&sbuf, "\n");
 266                         }
 267                 }
 268         }
 269         error = sbuf_finish(&sbuf);
 270         sbuf_delete(&sbuf);
 271         return (error);
 272 }
 273
 274 /*
 275  * Outputs the set of physical memory segments.
 276  */
 277 static int
 278 sysctl_vm_phys_segs(SYSCTL_HANDLER_ARGS)
 279 {
 280         struct sbuf sbuf;
 281         struct vm_phys_seg *seg;
 282         int error, segind;
 283
 284         error = sysctl_wire_old_buffer(req, 0);
 285         if (error != 0)
 286                 return (error);
 287         sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
 288         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 289                 sbuf_printf(&sbuf, "\nSEGMENT %d:\n\n", segind);
 290                 seg = &vm_phys_segs[segind];
 291                 sbuf_printf(&sbuf, "start:     %#jx\n",
 292                     (uintmax_t)seg->start);
 293                 sbuf_printf(&sbuf, "end:       %#jx\n",
 294                     (uintmax_t)seg->end);
 295                 sbuf_printf(&sbuf, "domain:    %d\n", seg->domain);
 296                 sbuf_printf(&sbuf, "free list: %p\n", seg->free_queues);
 297         }
 298         error = sbuf_finish(&sbuf);
 299         sbuf_delete(&sbuf);
 300         return (error);
 301 }
 302
 303 /*
 304  * Return affinity, or -1 if there's no affinity information.
 305  */
 306 int
 307 vm_phys_mem_affinity(int f, int t)
 308 {
 309
 310 #ifdef NUMA
 311         if (mem_locality == NULL)
 312                 return (-1);
 313         if (f >= vm_ndomains || t >= vm_ndomains)
 314                 return (-1);
 315         return (mem_locality[f * vm_ndomains + t]);
 316 #else
 317         return (-1);
 318 #endif
 319 }
 320
 321 #ifdef NUMA
 322 /*
 323  * Outputs the VM locality table.
 324  */
 325 static int
 326 sysctl_vm_phys_locality(SYSCTL_HANDLER_ARGS)
 327 {
 328         struct sbuf sbuf;
 329         int error, i, j;
 330
 331         error = sysctl_wire_old_buffer(req, 0);
 332         if (error != 0)
 333                 return (error);
 334         sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
 335
 336         sbuf_printf(&sbuf, "\n");
 337
 338         for (i = 0; i < vm_ndomains; i++) {
 339                 sbuf_printf(&sbuf, "%d: ", i);
 340                 for (j = 0; j < vm_ndomains; j++) {
 341                         sbuf_printf(&sbuf, "%d ", vm_phys_mem_affinity(i, j));
 342                 }
 343                 sbuf_printf(&sbuf, "\n");
 344         }
 345         error = sbuf_finish(&sbuf);
 346         sbuf_delete(&sbuf);
 347         return (error);
 348 }
 349 #endif
 350
 351 static void
 352 vm_freelist_add(struct vm_freelist *fl, vm_page_t m, int order, int tail)
 353 {
 354
 355         m->order = order;
 356         if (tail)
 357                 TAILQ_INSERT_TAIL(&fl[order].pl, m, listq);
 358         else
 359                 TAILQ_INSERT_HEAD(&fl[order].pl, m, listq);
 360         fl[order].lcnt++;
 361 }
 362
 363 static void
 364 vm_freelist_rem(struct vm_freelist *fl, vm_page_t m, int order)
 365 {
 366
 367         TAILQ_REMOVE(&fl[order].pl, m, listq);
 368         fl[order].lcnt--;
 369         m->order = VM_NFREEORDER;
 370 }
 371
 372 /*
 373  * Create a physical memory segment.
 374  */
 375 static void
 376 _vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int domain)
 377 {
 378         struct vm_phys_seg *seg;
 379
 380         KASSERT(vm_phys_nsegs < VM_PHYSSEG_MAX,
 381             ("vm_phys_create_seg: increase VM_PHYSSEG_MAX"));
 382         KASSERT(domain >= 0 && domain < vm_ndomains,
 383             ("vm_phys_create_seg: invalid domain provided"));
 384         seg = &vm_phys_segs[vm_phys_nsegs++];
 385         while (seg > vm_phys_segs && (seg - 1)->start >= end) {
 386                 *seg = *(seg - 1);
 387                 seg--;
 388         }
 389         seg->start = start;
 390         seg->end = end;
 391         seg->domain = domain;
 392 }
 393
 394 static void
 395 vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end)
 396 {
 397 #ifdef NUMA
 398         int i;
 399
 400         if (mem_affinity == NULL) {
 401                 _vm_phys_create_seg(start, end, 0);
 402                 return;
 403         }
 404
 405         for (i = 0;; i++) {
 406                 if (mem_affinity[i].end == 0)
 407                         panic("Reached end of affinity info");
 408                 if (mem_affinity[i].end <= start)
 409                         continue;
 410                 if (mem_affinity[i].start > start)
 411                         panic("No affinity info for start %jx",
 412                             (uintmax_t)start);
 413                 if (mem_affinity[i].end >= end) {
 414                         _vm_phys_create_seg(start, end,
 415                             mem_affinity[i].domain);
 416                         break;
 417                 }
 418                 _vm_phys_create_seg(start, mem_affinity[i].end,
 419                     mem_affinity[i].domain);
 420                 start = mem_affinity[i].end;
 421         }
 422 #else
 423         _vm_phys_create_seg(start, end, 0);
 424 #endif
 425 }
 426
 427 /*
 428  * Add a physical memory segment.
 429  */
 430 void
 431 vm_phys_add_seg(vm_paddr_t start, vm_paddr_t end)
 432 {
 433         vm_paddr_t paddr;
 434
 435         KASSERT((start & PAGE_MASK) == 0,
 436             ("vm_phys_define_seg: start is not page aligned"));
 437         KASSERT((end & PAGE_MASK) == 0,
 438             ("vm_phys_define_seg: end is not page aligned"));
 439
 440         /*
 441          * Split the physical memory segment if it spans two or more free
 442          * list boundaries.
 443          */
 444         paddr = start;
 445 #ifdef  VM_FREELIST_ISADMA
 446         if (paddr < VM_ISADMA_BOUNDARY && end > VM_ISADMA_BOUNDARY) {
 447                 vm_phys_create_seg(paddr, VM_ISADMA_BOUNDARY);
 448                 paddr = VM_ISADMA_BOUNDARY;
 449         }
 450 #endif
 451 #ifdef  VM_FREELIST_LOWMEM
 452         if (paddr < VM_LOWMEM_BOUNDARY && end > VM_LOWMEM_BOUNDARY) {
 453                 vm_phys_create_seg(paddr, VM_LOWMEM_BOUNDARY);
 454                 paddr = VM_LOWMEM_BOUNDARY;
 455         }
 456 #endif
 457 #ifdef  VM_FREELIST_DMA32
 458         if (paddr < VM_DMA32_BOUNDARY && end > VM_DMA32_BOUNDARY) {
 459                 vm_phys_create_seg(paddr, VM_DMA32_BOUNDARY);
 460                 paddr = VM_DMA32_BOUNDARY;
 461         }
 462 #endif
 463         vm_phys_create_seg(paddr, end);
 464 }
 465
 466 /*
 467  * Initialize the physical memory allocator.
 468  *
 469  * Requires that vm_page_array is initialized!
 470  */
 471 void
 472 vm_phys_init(void)
 473 {
 474         struct vm_freelist *fl;
 475         struct vm_phys_seg *seg;
 476         u_long npages;
 477         int dom, flind, freelist, oind, pind, segind;
 478
 479         /*
 480          * Compute the number of free lists, and generate the mapping from the
 481          * manifest constants VM_FREELIST_* to the free list indices.
 482          *
 483          * Initially, the entries of vm_freelist_to_flind[] are set to either
 484          * 0 or 1 to indicate which free lists should be created.
 485          */
 486         npages = 0;
 487         for (segind = vm_phys_nsegs - 1; segind >= 0; segind--) {
 488                 seg = &vm_phys_segs[segind];
 489 #ifdef  VM_FREELIST_ISADMA
 490                 if (seg->end <= VM_ISADMA_BOUNDARY)
 491                         vm_freelist_to_flind[VM_FREELIST_ISADMA] = 1;
 492                 else
 493 #endif
 494 #ifdef  VM_FREELIST_LOWMEM
 495                 if (seg->end <= VM_LOWMEM_BOUNDARY)
 496                         vm_freelist_to_flind[VM_FREELIST_LOWMEM] = 1;
 497                 else
 498 #endif
 499 #ifdef  VM_FREELIST_DMA32
 500                 if (
 501 #ifdef  VM_DMA32_NPAGES_THRESHOLD
 502                     /*
 503                      * Create the DMA32 free list only if the amount of
 504                      * physical memory above physical address 4G exceeds the
 505                      * given threshold.
 506                      */
 507                     npages > VM_DMA32_NPAGES_THRESHOLD &&
 508 #endif
 509                     seg->end <= VM_DMA32_BOUNDARY)
 510                         vm_freelist_to_flind[VM_FREELIST_DMA32] = 1;
 511                 else
 512 #endif
 513                 {
 514                         npages += atop(seg->end - seg->start);
 515                         vm_freelist_to_flind[VM_FREELIST_DEFAULT] = 1;
 516                 }
 517         }
 518         /* Change each entry into a running total of the free lists. */
 519         for (freelist = 1; freelist < VM_NFREELIST; freelist++) {
 520                 vm_freelist_to_flind[freelist] +=
 521                     vm_freelist_to_flind[freelist - 1];
 522         }
 523         vm_nfreelists = vm_freelist_to_flind[VM_NFREELIST - 1];
 524         KASSERT(vm_nfreelists > 0, ("vm_phys_init: no free lists"));
 525         /* Change each entry into a free list index. */
 526         for (freelist = 0; freelist < VM_NFREELIST; freelist++)
 527                 vm_freelist_to_flind[freelist]--;
 528
 529         /*
 530          * Initialize the first_page and free_queues fields of each physical
 531          * memory segment.
 532          */
 533 #ifdef VM_PHYSSEG_SPARSE
 534         npages = 0;
 535 #endif
 536         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 537                 seg = &vm_phys_segs[segind];
 538 #ifdef VM_PHYSSEG_SPARSE
 539                 seg->first_page = &vm_page_array[npages];
 540                 npages += atop(seg->end - seg->start);
 541 #else
 542                 seg->first_page = PHYS_TO_VM_PAGE(seg->start);
 543 #endif
 544 #ifdef  VM_FREELIST_ISADMA
 545                 if (seg->end <= VM_ISADMA_BOUNDARY) {
 546                         flind = vm_freelist_to_flind[VM_FREELIST_ISADMA];
 547                         KASSERT(flind >= 0,
 548                             ("vm_phys_init: ISADMA flind < 0"));
 549                 } else
 550 #endif
 551 #ifdef  VM_FREELIST_LOWMEM
 552                 if (seg->end <= VM_LOWMEM_BOUNDARY) {
 553                         flind = vm_freelist_to_flind[VM_FREELIST_LOWMEM];
 554                         KASSERT(flind >= 0,
 555                             ("vm_phys_init: LOWMEM flind < 0"));
 556                 } else
 557 #endif
 558 #ifdef  VM_FREELIST_DMA32
 559                 if (seg->end <= VM_DMA32_BOUNDARY) {
 560                         flind = vm_freelist_to_flind[VM_FREELIST_DMA32];
 561                         KASSERT(flind >= 0,
 562                             ("vm_phys_init: DMA32 flind < 0"));
 563                 } else
 564 #endif
 565                 {
 566                         flind = vm_freelist_to_flind[VM_FREELIST_DEFAULT];
 567                         KASSERT(flind >= 0,
 568                             ("vm_phys_init: DEFAULT flind < 0"));
 569                 }
 570                 seg->free_queues = &vm_phys_free_queues[seg->domain][flind];
 571         }
 572
 573         /*
 574          * Initialize the free queues.
 575          */
 576         for (dom = 0; dom < vm_ndomains; dom++) {
 577                 for (flind = 0; flind < vm_nfreelists; flind++) {
 578                         for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 579                                 fl = vm_phys_free_queues[dom][flind][pind];
 580                                 for (oind = 0; oind < VM_NFREEORDER; oind++)
 581                                         TAILQ_INIT(&fl[oind].pl);
 582                         }
 583                 }
 584         }
 585
 586         rw_init(&vm_phys_fictitious_reg_lock, "vmfctr");
 587 }
 588
 589 /*
 590  * Split a contiguous, power of two-sized set of physical pages.
 591  */
 592 static __inline void
 593 vm_phys_split_pages(vm_page_t m, int oind, struct vm_freelist *fl, int order)
 594 {
 595         vm_page_t m_buddy;
 596
 597         while (oind > order) {
 598                 oind--;
 599                 m_buddy = &m[1 << oind];
 600                 KASSERT(m_buddy->order == VM_NFREEORDER,
 601                     ("vm_phys_split_pages: page %p has unexpected order %d",
 602                     m_buddy, m_buddy->order));
 603                 vm_freelist_add(fl, m_buddy, oind, 0);
 604         }
 605 }
 606
 607 /*
 608  * Add the physical pages [m, m + npages) at the end of a power-of-two aligned
 609  * and sized set to the specified free list.
 610  *
 611  * When this function is called by a page allocation function, the caller
 612  * should request insertion at the head unless the lower-order queues are
 613  * known to be empty.  The objective being to reduce the likelihood of long-
 614  * term fragmentation by promoting contemporaneous allocation and (hopefully)
 615  * deallocation.
 616  *
 617  * The physical page m's buddy must not be free.
 618  */
 619 static void
 620 vm_phys_enq_range(vm_page_t m, u_int npages, struct vm_freelist *fl, int tail)
 621 {
 622         u_int n;
 623         int order;
 624
 625         KASSERT(npages > 0, ("vm_phys_enq_range: npages is 0"));
 626         KASSERT(((VM_PAGE_TO_PHYS(m) + npages * PAGE_SIZE) &
 627             ((PAGE_SIZE << (fls(npages) - 1)) - 1)) == 0,
 628             ("vm_phys_enq_range: page %p and npages %u are misaligned",
 629             m, npages));
 630         do {
 631                 KASSERT(m->order == VM_NFREEORDER,
 632                     ("vm_phys_enq_range: page %p has unexpected order %d",
 633                     m, m->order));
 634                 order = ffs(npages) - 1;
 635                 KASSERT(order < VM_NFREEORDER,
 636                     ("vm_phys_enq_range: order %d is out of range", order));
 637                 vm_freelist_add(fl, m, order, tail);
 638                 n = 1 << order;
 639                 m += n;
 640                 npages -= n;
 641         } while (npages > 0);
 642 }
 643
 644 /*
 645  * Tries to allocate the specified number of pages from the specified pool
 646  * within the specified domain.  Returns the actual number of allocated pages
 647  * and a pointer to each page through the array ma[].
 648  *
 649  * The returned pages may not be physically contiguous.  However, in contrast
 650  * to performing multiple, back-to-back calls to vm_phys_alloc_pages(..., 0),
 651  * calling this function once to allocate the desired number of pages will
 652  * avoid wasted time in vm_phys_split_pages().
 653  *
 654  * The free page queues for the specified domain must be locked.
 655  */
 656 int
 657 vm_phys_alloc_npages(int domain, int pool, int npages, vm_page_t ma[])
 658 {
 659         struct vm_freelist *alt, *fl;
 660         vm_page_t m;
 661         int avail, end, flind, freelist, i, need, oind, pind;
 662
 663         KASSERT(domain >= 0 && domain < vm_ndomains,
 664             ("vm_phys_alloc_npages: domain %d is out of range", domain));
 665         KASSERT(pool < VM_NFREEPOOL,
 666             ("vm_phys_alloc_npages: pool %d is out of range", pool));
 667         KASSERT(npages <= 1 << (VM_NFREEORDER - 1),
 668             ("vm_phys_alloc_npages: npages %d is out of range", npages));
 669         vm_domain_free_assert_locked(VM_DOMAIN(domain));
 670         i = 0;
 671         for (freelist = 0; freelist < VM_NFREELIST; freelist++) {
 672                 flind = vm_freelist_to_flind[freelist];
 673                 if (flind < 0)
 674                         continue;
 675                 fl = vm_phys_free_queues[domain][flind][pool];
 676                 for (oind = 0; oind < VM_NFREEORDER; oind++) {
 677                         while ((m = TAILQ_FIRST(&fl[oind].pl)) != NULL) {
 678                                 vm_freelist_rem(fl, m, oind);
 679                                 avail = 1 << oind;
 680                                 need = imin(npages - i, avail);
 681                                 for (end = i + need; i < end;)
 682                                         ma[i++] = m++;
 683                                 if (need < avail) {
 684                                         /*
 685                                          * Return excess pages to fl.  Its
 686                                          * order [0, oind) queues are empty.
 687                                          */
 688                                         vm_phys_enq_range(m, avail - need, fl,
 689                                             1);
 690                                         return (npages);
 691                                 } else if (i == npages)
 692                                         return (npages);
 693                         }
 694                 }
 695                 for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
 696                         for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 697                                 alt = vm_phys_free_queues[domain][flind][pind];
 698                                 while ((m = TAILQ_FIRST(&alt[oind].pl)) !=
 699                                     NULL) {
 700                                         vm_freelist_rem(alt, m, oind);
 701                                         vm_phys_set_pool(pool, m, oind);
 702                                         avail = 1 << oind;
 703                                         need = imin(npages - i, avail);
 704                                         for (end = i + need; i < end;)
 705                                                 ma[i++] = m++;
 706                                         if (need < avail) {
 707                                                 /*
 708                                                  * Return excess pages to fl.
 709                                                  * Its order [0, oind) queues
 710                                                  * are empty.
 711                                                  */
 712                                                 vm_phys_enq_range(m, avail -
 713                                                     need, fl, 1);
 714                                                 return (npages);
 715                                         } else if (i == npages)
 716                                                 return (npages);
 717                                 }
 718                         }
 719                 }
 720         }
 721         return (i);
 722 }
 723
 724 /*
 725  * Allocate a contiguous, power of two-sized set of physical pages
 726  * from the free lists.
 727  *
 728  * The free page queues must be locked.
 729  */
 730 vm_page_t
 731 vm_phys_alloc_pages(int domain, int pool, int order)
 732 {
 733         vm_page_t m;
 734         int freelist;
 735
 736         for (freelist = 0; freelist < VM_NFREELIST; freelist++) {
 737                 m = vm_phys_alloc_freelist_pages(domain, freelist, pool, order);
 738                 if (m != NULL)
 739                         return (m);
 740         }
 741         return (NULL);
 742 }
 743
 744 /*
 745  * Allocate a contiguous, power of two-sized set of physical pages from the
 746  * specified free list.  The free list must be specified using one of the
 747  * manifest constants VM_FREELIST_*.
 748  *
 749  * The free page queues must be locked.
 750  */
 751 vm_page_t
 752 vm_phys_alloc_freelist_pages(int domain, int freelist, int pool, int order)
 753 {
 754         struct vm_freelist *alt, *fl;
 755         vm_page_t m;
 756         int oind, pind, flind;
 757
 758         KASSERT(domain >= 0 && domain < vm_ndomains,
 759             ("vm_phys_alloc_freelist_pages: domain %d is out of range",
 760             domain));
 761         KASSERT(freelist < VM_NFREELIST,
 762             ("vm_phys_alloc_freelist_pages: freelist %d is out of range",
 763             freelist));
 764         KASSERT(pool < VM_NFREEPOOL,
 765             ("vm_phys_alloc_freelist_pages: pool %d is out of range", pool));
 766         KASSERT(order < VM_NFREEORDER,
 767             ("vm_phys_alloc_freelist_pages: order %d is out of range", order));
 768
 769         flind = vm_freelist_to_flind[freelist];
 770         /* Check if freelist is present */
 771         if (flind < 0)
 772                 return (NULL);
 773
 774         vm_domain_free_assert_locked(VM_DOMAIN(domain));
 775         fl = &vm_phys_free_queues[domain][flind][pool][0];
 776         for (oind = order; oind < VM_NFREEORDER; oind++) {
 777                 m = TAILQ_FIRST(&fl[oind].pl);
 778                 if (m != NULL) {
 779                         vm_freelist_rem(fl, m, oind);
 780                         vm_phys_split_pages(m, oind, fl, order);
 781                         return (m);
 782                 }
 783         }
 784
 785         /*
 786          * The given pool was empty.  Find the largest
 787          * contiguous, power-of-two-sized set of pages in any
 788          * pool.  Transfer these pages to the given pool, and
 789          * use them to satisfy the allocation.
 790          */
 791         for (oind = VM_NFREEORDER - 1; oind >= order; oind--) {
 792                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 793                         alt = &vm_phys_free_queues[domain][flind][pind][0];
 794                         m = TAILQ_FIRST(&alt[oind].pl);
 795                         if (m != NULL) {
 796                                 vm_freelist_rem(alt, m, oind);
 797                                 vm_phys_set_pool(pool, m, oind);
 798                                 vm_phys_split_pages(m, oind, fl, order);
 799                                 return (m);
 800                         }
 801                 }
 802         }
 803         return (NULL);
 804 }
 805
 806 /*
 807  * Find the vm_page corresponding to the given physical address.
 808  */
 809 vm_page_t
 810 vm_phys_paddr_to_vm_page(vm_paddr_t pa)
 811 {
 812         struct vm_phys_seg *seg;
 813         int segind;
 814
 815         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 816                 seg = &vm_phys_segs[segind];
 817                 if (pa >= seg->start && pa < seg->end)
 818                         return (&seg->first_page[atop(pa - seg->start)]);
 819         }
 820         return (NULL);
 821 }
 822
 823 vm_page_t
 824 vm_phys_fictitious_to_vm_page(vm_paddr_t pa)
 825 {
 826         struct vm_phys_fictitious_seg tmp, *seg;
 827         vm_page_t m;
 828
 829         m = NULL;
 830         tmp.start = pa;
 831         tmp.end = 0;
 832
 833         rw_rlock(&vm_phys_fictitious_reg_lock);
 834         seg = RB_FIND(fict_tree, &vm_phys_fictitious_tree, &tmp);
 835         rw_runlock(&vm_phys_fictitious_reg_lock);
 836         if (seg == NULL)
 837                 return (NULL);
 838
 839         m = &seg->first_page[atop(pa - seg->start)];
 840         KASSERT((m->flags & PG_FICTITIOUS) != 0, ("%p not fictitious", m));
 841
 842         return (m);
 843 }
 844
 845 static inline void
 846 vm_phys_fictitious_init_range(vm_page_t range, vm_paddr_t start,
 847     long page_count, vm_memattr_t memattr)
 848 {
 849         long i;
 850
 851         bzero(range, page_count * sizeof(*range));
 852         for (i = 0; i < page_count; i++) {
 853                 vm_page_initfake(&range[i], start + PAGE_SIZE * i, memattr);
 854                 range[i].oflags &= ~VPO_UNMANAGED;
 855                 range[i].busy_lock = VPB_UNBUSIED;
 856         }
 857 }
 858
 859 int
 860 vm_phys_fictitious_reg_range(vm_paddr_t start, vm_paddr_t end,
 861     vm_memattr_t memattr)
 862 {
 863         struct vm_phys_fictitious_seg *seg;
 864         vm_page_t fp;
 865         long page_count;
 866 #ifdef VM_PHYSSEG_DENSE
 867         long pi, pe;
 868         long dpage_count;
 869 #endif
 870
 871         KASSERT(start < end,
 872             ("Start of segment isn't less than end (start: %jx end: %jx)",
 873             (uintmax_t)start, (uintmax_t)end));
 874
 875         page_count = (end - start) / PAGE_SIZE;
 876
 877 #ifdef VM_PHYSSEG_DENSE
 878         pi = atop(start);
 879         pe = atop(end);
 880         if (pi >= first_page && (pi - first_page) < vm_page_array_size) {
 881                 fp = &vm_page_array[pi - first_page];
 882                 if ((pe - first_page) > vm_page_array_size) {
 883                         /*
 884                          * We have a segment that starts inside
 885                          * of vm_page_array, but ends outside of it.
 886                          *
 887                          * Use vm_page_array pages for those that are
 888                          * inside of the vm_page_array range, and
 889                          * allocate the remaining ones.
 890                          */
 891                         dpage_count = vm_page_array_size - (pi - first_page);
 892                         vm_phys_fictitious_init_range(fp, start, dpage_count,
 893                             memattr);
 894                         page_count -= dpage_count;
 895                         start += ptoa(dpage_count);
 896                         goto alloc;
 897                 }
 898                 /*
 899                  * We can allocate the full range from vm_page_array,
 900                  * so there's no need to register the range in the tree.
 901                  */
 902                 vm_phys_fictitious_init_range(fp, start, page_count, memattr);
 903                 return (0);
 904         } else if (pe > first_page && (pe - first_page) < vm_page_array_size) {
 905                 /*
 906                  * We have a segment that ends inside of vm_page_array,
 907                  * but starts outside of it.
 908                  */
 909                 fp = &vm_page_array[0];
 910                 dpage_count = pe - first_page;
 911                 vm_phys_fictitious_init_range(fp, ptoa(first_page), dpage_count,
 912                     memattr);
 913                 end -= ptoa(dpage_count);
 914                 page_count -= dpage_count;
 915                 goto alloc;
 916         } else if (pi < first_page && pe > (first_page + vm_page_array_size)) {
 917                 /*
 918                  * Trying to register a fictitious range that expands before
 919                  * and after vm_page_array.
 920                  */
 921                 return (EINVAL);
 922         } else {
 923 alloc:
 924 #endif
 925                 fp = malloc(page_count * sizeof(struct vm_page), M_FICT_PAGES,
 926                     M_WAITOK);
 927 #ifdef VM_PHYSSEG_DENSE
 928         }
 929 #endif
 930         vm_phys_fictitious_init_range(fp, start, page_count, memattr);
 931
 932         seg = malloc(sizeof(*seg), M_FICT_PAGES, M_WAITOK | M_ZERO);
 933         seg->start = start;
 934         seg->end = end;
 935         seg->first_page = fp;
 936
 937         rw_wlock(&vm_phys_fictitious_reg_lock);
 938         RB_INSERT(fict_tree, &vm_phys_fictitious_tree, seg);
 939         rw_wunlock(&vm_phys_fictitious_reg_lock);
 940
 941         return (0);
 942 }
 943
 944 void
 945 vm_phys_fictitious_unreg_range(vm_paddr_t start, vm_paddr_t end)
 946 {
 947         struct vm_phys_fictitious_seg *seg, tmp;
 948 #ifdef VM_PHYSSEG_DENSE
 949         long pi, pe;
 950 #endif
 951
 952         KASSERT(start < end,
 953             ("Start of segment isn't less than end (start: %jx end: %jx)",
 954             (uintmax_t)start, (uintmax_t)end));
 955
 956 #ifdef VM_PHYSSEG_DENSE
 957         pi = atop(start);
 958         pe = atop(end);
 959         if (pi >= first_page && (pi - first_page) < vm_page_array_size) {
 960                 if ((pe - first_page) <= vm_page_array_size) {
 961                         /*
 962                          * This segment was allocated using vm_page_array
 963                          * only, there's nothing to do since those pages
 964                          * were never added to the tree.
 965                          */
 966                         return;
 967                 }
 968                 /*
 969                  * We have a segment that starts inside
 970                  * of vm_page_array, but ends outside of it.
 971                  *
 972                  * Calculate how many pages were added to the
 973                  * tree and free them.
 974                  */
 975                 start = ptoa(first_page + vm_page_array_size);
 976         } else if (pe > first_page && (pe - first_page) < vm_page_array_size) {
 977                 /*
 978                  * We have a segment that ends inside of vm_page_array,
 979                  * but starts outside of it.
 980                  */
 981                 end = ptoa(first_page);
 982         } else if (pi < first_page && pe > (first_page + vm_page_array_size)) {
 983                 /* Since it's not possible to register such a range, panic. */
 984                 panic(
 985                     "Unregistering not registered fictitious range [%#jx:%#jx]",
 986                     (uintmax_t)start, (uintmax_t)end);
 987         }
 988 #endif
 989         tmp.start = start;
 990         tmp.end = 0;
 991
 992         rw_wlock(&vm_phys_fictitious_reg_lock);
 993         seg = RB_FIND(fict_tree, &vm_phys_fictitious_tree, &tmp);
 994         if (seg->start != start || seg->end != end) {
 995                 rw_wunlock(&vm_phys_fictitious_reg_lock);
 996                 panic(
 997                     "Unregistering not registered fictitious range [%#jx:%#jx]",
 998                     (uintmax_t)start, (uintmax_t)end);
 999         }
1000         RB_REMOVE(fict_tree, &vm_phys_fictitious_tree, seg);
1001         rw_wunlock(&vm_phys_fictitious_reg_lock);
1002         free(seg->first_page, M_FICT_PAGES);
1003         free(seg, M_FICT_PAGES);
1004 }
1005
1006 /*
1007  * Free a contiguous, power of two-sized set of physical pages.
1008  *
1009  * The free page queues must be locked.
1010  */
1011 void
1012 vm_phys_free_pages(vm_page_t m, int order)
1013 {
1014         struct vm_freelist *fl;
1015         struct vm_phys_seg *seg;
1016         vm_paddr_t pa;
1017         vm_page_t m_buddy;
1018
1019         KASSERT(m->order == VM_NFREEORDER,
1020             ("vm_phys_free_pages: page %p has unexpected order %d",
1021             m, m->order));
1022         KASSERT(m->pool < VM_NFREEPOOL,
1023             ("vm_phys_free_pages: page %p has unexpected pool %d",
1024             m, m->pool));
1025         KASSERT(order < VM_NFREEORDER,
1026             ("vm_phys_free_pages: order %d is out of range", order));
1027         seg = &vm_phys_segs[m->segind];
1028         vm_domain_free_assert_locked(VM_DOMAIN(seg->domain));
1029         if (order < VM_NFREEORDER - 1) {
1030                 pa = VM_PAGE_TO_PHYS(m);
1031                 do {
1032                         pa ^= ((vm_paddr_t)1 << (PAGE_SHIFT + order));
1033                         if (pa < seg->start || pa >= seg->end)
1034                                 break;
1035                         m_buddy = &seg->first_page[atop(pa - seg->start)];
1036                         if (m_buddy->order != order)
1037                                 break;
1038                         fl = (*seg->free_queues)[m_buddy->pool];
1039                         vm_freelist_rem(fl, m_buddy, order);
1040                         if (m_buddy->pool != m->pool)
1041                                 vm_phys_set_pool(m->pool, m_buddy, order);
1042                         order++;
1043                         pa &= ~(((vm_paddr_t)1 << (PAGE_SHIFT + order)) - 1);
1044                         m = &seg->first_page[atop(pa - seg->start)];
1045                 } while (order < VM_NFREEORDER - 1);
1046         }
1047         fl = (*seg->free_queues)[m->pool];
1048         vm_freelist_add(fl, m, order, 1);
1049 }
1050
1051 /*
1052  * Free a contiguous, arbitrarily sized set of physical pages.
1053  *
1054  * The free page queues must be locked.
1055  */
1056 void
1057 vm_phys_free_contig(vm_page_t m, u_long npages)
1058 {
1059         u_int n;
1060         int order;
1061
1062         /*
1063          * Avoid unnecessary coalescing by freeing the pages in the largest
1064          * possible power-of-two-sized subsets.
1065          */
1066         vm_domain_free_assert_locked(vm_pagequeue_domain(m));
1067         for (;; npages -= n) {
1068                 /*
1069                  * Unsigned "min" is used here so that "order" is assigned
1070                  * "VM_NFREEORDER - 1" when "m"'s physical address is zero
1071                  * or the low-order bits of its physical address are zero
1072                  * because the size of a physical address exceeds the size of
1073                  * a long.
1074                  */
1075                 order = min(ffsl(VM_PAGE_TO_PHYS(m) >> PAGE_SHIFT) - 1,
1076                     VM_NFREEORDER - 1);
1077                 n = 1 << order;
1078                 if (npages < n)
1079                         break;
1080                 vm_phys_free_pages(m, order);
1081                 m += n;
1082         }
1083         /* The residual "npages" is less than "1 << (VM_NFREEORDER - 1)". */
1084         for (; npages > 0; npages -= n) {
1085                 order = flsl(npages) - 1;
1086                 n = 1 << order;
1087                 vm_phys_free_pages(m, order);
1088                 m += n;
1089         }
1090 }
1091
1092 /*
1093  * Scan physical memory between the specified addresses "low" and "high" for a
1094  * run of contiguous physical pages that satisfy the specified conditions, and
1095  * return the lowest page in the run.  The specified "alignment" determines
1096  * the alignment of the lowest physical page in the run.  If the specified
1097  * "boundary" is non-zero, then the run of physical pages cannot span a
1098  * physical address that is a multiple of "boundary".
1099  *
1100  * "npages" must be greater than zero.  Both "alignment" and "boundary" must
1101  * be a power of two.
1102  */
1103 vm_page_t
1104 vm_phys_scan_contig(int domain, u_long npages, vm_paddr_t low, vm_paddr_t high,
1105     u_long alignment, vm_paddr_t boundary, int options)
1106 {
1107         vm_paddr_t pa_end;
1108         vm_page_t m_end, m_run, m_start;
1109         struct vm_phys_seg *seg;
1110         int segind;
1111
1112         KASSERT(npages > 0, ("npages is 0"));
1113         KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
1114         KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
1115         if (low >= high)
1116                 return (NULL);
1117         for (segind = 0; segind < vm_phys_nsegs; segind++) {
1118                 seg = &vm_phys_segs[segind];
1119                 if (seg->domain != domain)
1120                         continue;
1121                 if (seg->start >= high)
1122                         break;
1123                 if (low >= seg->end)
1124                         continue;
1125                 if (low <= seg->start)
1126                         m_start = seg->first_page;
1127                 else
1128                         m_start = &seg->first_page[atop(low - seg->start)];
1129                 if (high < seg->end)
1130                         pa_end = high;
1131                 else
1132                         pa_end = seg->end;
1133                 if (pa_end - VM_PAGE_TO_PHYS(m_start) < ptoa(npages))
1134                         continue;
1135                 m_end = &seg->first_page[atop(pa_end - seg->start)];
1136                 m_run = vm_page_scan_contig(npages, m_start, m_end,
1137                     alignment, boundary, options);
1138                 if (m_run != NULL)
1139                         return (m_run);
1140         }
1141         return (NULL);
1142 }
1143
1144 /*
1145  * Set the pool for a contiguous, power of two-sized set of physical pages.
1146  */
1147 void
1148 vm_phys_set_pool(int pool, vm_page_t m, int order)
1149 {
1150         vm_page_t m_tmp;
1151
1152         for (m_tmp = m; m_tmp < &m[1 << order]; m_tmp++)
1153                 m_tmp->pool = pool;
1154 }
1155
1156 /*
1157  * Search for the given physical page "m" in the free lists.  If the search
1158  * succeeds, remove "m" from the free lists and return TRUE.  Otherwise, return
1159  * FALSE, indicating that "m" is not in the free lists.
1160  *
1161  * The free page queues must be locked.
1162  */
1163 boolean_t
1164 vm_phys_unfree_page(vm_page_t m)
1165 {
1166         struct vm_freelist *fl;
1167         struct vm_phys_seg *seg;
1168         vm_paddr_t pa, pa_half;
1169         vm_page_t m_set, m_tmp;
1170         int order;
1171
1172         /*
1173          * First, find the contiguous, power of two-sized set of free
1174          * physical pages containing the given physical page "m" and
1175          * assign it to "m_set".
1176          */
1177         seg = &vm_phys_segs[m->segind];
1178         vm_domain_free_assert_locked(VM_DOMAIN(seg->domain));
1179         for (m_set = m, order = 0; m_set->order == VM_NFREEORDER &&
1180             order < VM_NFREEORDER - 1; ) {
1181                 order++;
1182                 pa = m->phys_addr & (~(vm_paddr_t)0 << (PAGE_SHIFT + order));
1183                 if (pa >= seg->start)
1184                         m_set = &seg->first_page[atop(pa - seg->start)];
1185                 else
1186                         return (FALSE);
1187         }
1188         if (m_set->order < order)
1189                 return (FALSE);
1190         if (m_set->order == VM_NFREEORDER)
1191                 return (FALSE);
1192         KASSERT(m_set->order < VM_NFREEORDER,
1193             ("vm_phys_unfree_page: page %p has unexpected order %d",
1194             m_set, m_set->order));
1195
1196         /*
1197          * Next, remove "m_set" from the free lists.  Finally, extract
1198          * "m" from "m_set" using an iterative algorithm: While "m_set"
1199          * is larger than a page, shrink "m_set" by returning the half
1200          * of "m_set" that does not contain "m" to the free lists.
1201          */
1202         fl = (*seg->free_queues)[m_set->pool];
1203         order = m_set->order;
1204         vm_freelist_rem(fl, m_set, order);
1205         while (order > 0) {
1206                 order--;
1207                 pa_half = m_set->phys_addr ^ (1 << (PAGE_SHIFT + order));
1208                 if (m->phys_addr < pa_half)
1209                         m_tmp = &seg->first_page[atop(pa_half - seg->start)];
1210                 else {
1211                         m_tmp = m_set;
1212                         m_set = &seg->first_page[atop(pa_half - seg->start)];
1213                 }
1214                 vm_freelist_add(fl, m_tmp, order, 0);
1215         }
1216         KASSERT(m_set == m, ("vm_phys_unfree_page: fatal inconsistency"));
1217         return (TRUE);
1218 }
1219
1220 /*
1221  * Allocate a contiguous set of physical pages of the given size
1222  * "npages" from the free lists.  All of the physical pages must be at
1223  * or above the given physical address "low" and below the given
1224  * physical address "high".  The given value "alignment" determines the
1225  * alignment of the first physical page in the set.  If the given value
1226  * "boundary" is non-zero, then the set of physical pages cannot cross
1227  * any physical address boundary that is a multiple of that value.  Both
1228  * "alignment" and "boundary" must be a power of two.
1229  */
1230 vm_page_t
1231 vm_phys_alloc_contig(int domain, u_long npages, vm_paddr_t low, vm_paddr_t high,
1232     u_long alignment, vm_paddr_t boundary)
1233 {
1234         vm_paddr_t pa_end, pa_start;
1235         vm_page_t m_run;
1236         struct vm_phys_seg *seg;
1237         int segind;
1238
1239         KASSERT(npages > 0, ("npages is 0"));
1240         KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
1241         KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
1242         vm_domain_free_assert_locked(VM_DOMAIN(domain));
1243         if (low >= high)
1244                 return (NULL);
1245         m_run = NULL;
1246         for (segind = vm_phys_nsegs - 1; segind >= 0; segind--) {
1247                 seg = &vm_phys_segs[segind];
1248                 if (seg->start >= high || seg->domain != domain)
1249                         continue;
1250                 if (low >= seg->end)
1251                         break;
1252                 if (low <= seg->start)
1253                         pa_start = seg->start;
1254                 else
1255                         pa_start = low;
1256                 if (high < seg->end)
1257                         pa_end = high;
1258                 else
1259                         pa_end = seg->end;
1260                 if (pa_end - pa_start < ptoa(npages))
1261                         continue;
1262                 m_run = vm_phys_alloc_seg_contig(seg, npages, low, high,
1263                     alignment, boundary);
1264                 if (m_run != NULL)
1265                         break;
1266         }
1267         return (m_run);
1268 }
1269
1270 /*
1271  * Allocate a run of contiguous physical pages from the free list for the
1272  * specified segment.
1273  */
1274 static vm_page_t
1275 vm_phys_alloc_seg_contig(struct vm_phys_seg *seg, u_long npages,
1276     vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary)
1277 {
1278         struct vm_freelist *fl;
1279         vm_paddr_t pa, pa_end, size;
1280         vm_page_t m, m_ret;
1281         u_long npages_end;
1282         int oind, order, pind;
1283
1284         KASSERT(npages > 0, ("npages is 0"));
1285         KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
1286         KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
1287         vm_domain_free_assert_locked(VM_DOMAIN(seg->domain));
1288         /* Compute the queue that is the best fit for npages. */
1289         order = flsl(npages - 1);
1290         /* Search for a run satisfying the specified conditions. */
1291         size = npages << PAGE_SHIFT;
1292         for (oind = min(order, VM_NFREEORDER - 1); oind < VM_NFREEORDER;
1293             oind++) {
1294                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
1295                         fl = (*seg->free_queues)[pind];
1296                         TAILQ_FOREACH(m_ret, &fl[oind].pl, listq) {
1297                                 /*
1298                                  * Is the size of this allocation request
1299                                  * larger than the largest block size?
1300                                  */
1301                                 if (order >= VM_NFREEORDER) {
1302                                         /*
1303                                          * Determine if a sufficient number of
1304                                          * subsequent blocks to satisfy the
1305                                          * allocation request are free.
1306                                          */
1307                                         pa = VM_PAGE_TO_PHYS(m_ret);
1308                                         pa_end = pa + size;
1309                                         if (pa_end < pa)
1310                                                 continue;
1311                                         for (;;) {
1312                                                 pa += 1 << (PAGE_SHIFT +
1313                                                     VM_NFREEORDER - 1);
1314                                                 if (pa >= pa_end ||
1315                                                     pa < seg->start ||
1316                                                     pa >= seg->end)
1317                                                         break;
1318                                                 m = &seg->first_page[atop(pa -
1319                                                     seg->start)];
1320                                                 if (m->order != VM_NFREEORDER -
1321                                                     1)
1322                                                         break;
1323                                         }
1324                                         /* If not, go to the next block. */
1325                                         if (pa < pa_end)
1326                                                 continue;
1327                                 }
1328
1329                                 /*
1330                                  * Determine if the blocks are within the
1331                                  * given range, satisfy the given alignment,
1332                                  * and do not cross the given boundary.
1333                                  */
1334                                 pa = VM_PAGE_TO_PHYS(m_ret);
1335                                 pa_end = pa + size;
1336                                 if (pa >= low && pa_end <= high &&
1337                                     (pa & (alignment - 1)) == 0 &&
1338                                     rounddown2(pa ^ (pa_end - 1), boundary) == 0)
1339                                         goto done;
1340                         }
1341                 }
1342         }
1343         return (NULL);
1344 done:
1345         for (m = m_ret; m < &m_ret[npages]; m = &m[1 << oind]) {
1346                 fl = (*seg->free_queues)[m->pool];
1347                 vm_freelist_rem(fl, m, oind);
1348                 if (m->pool != VM_FREEPOOL_DEFAULT)
1349                         vm_phys_set_pool(VM_FREEPOOL_DEFAULT, m, oind);
1350         }
1351         /* Return excess pages to the free lists. */
1352         npages_end = roundup2(npages, 1 << oind);
1353         if (npages < npages_end) {
1354                 fl = (*seg->free_queues)[VM_FREEPOOL_DEFAULT];
1355                 vm_phys_enq_range(&m_ret[npages], npages_end - npages, fl, 0);
1356         }
1357         return (m_ret);
1358 }
1359
1360 #ifdef DDB
1361 /*
1362  * Show the number of physical pages in each of the free lists.
1363  */
1364 DB_SHOW_COMMAND(freepages, db_show_freepages)
1365 {
1366         struct vm_freelist *fl;
1367         int flind, oind, pind, dom;
1368
1369         for (dom = 0; dom < vm_ndomains; dom++) {
1370                 db_printf("DOMAIN: %d\n", dom);
1371                 for (flind = 0; flind < vm_nfreelists; flind++) {
1372                         db_printf("FREE LIST %d:\n"
1373                             "\n  ORDER (SIZE)  |  NUMBER"
1374                             "\n              ", flind);
1375                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
1376                                 db_printf("  |  POOL %d", pind);
1377                         db_printf("\n--            ");
1378                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
1379                                 db_printf("-- --      ");
1380                         db_printf("--\n");
1381                         for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
1382                                 db_printf("  %2.2d (%6.6dK)", oind,
1383                                     1 << (PAGE_SHIFT - 10 + oind));
1384                                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
1385                                 fl = vm_phys_free_queues[dom][flind][pind];
1386                                         db_printf("  |  %6.6d", fl[oind].lcnt);
1387                                 }
1388                                 db_printf("\n");
1389                         }
1390                         db_printf("\n");
1391                 }
1392                 db_printf("\n");
1393         }
1394 }
1395 #endif