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_DMA32
 119 #define VM_DMA32_BOUNDARY       ((vm_paddr_t)1 << 32)
 120 #endif
 121
 122 /*
 123  * Enforce the assumptions made by vm_phys_add_seg() and vm_phys_init() about
 124  * the ordering of the free list boundaries.
 125  */
 126 #if defined(VM_LOWMEM_BOUNDARY) && defined(VM_DMA32_BOUNDARY)
 127 CTASSERT(VM_LOWMEM_BOUNDARY < VM_DMA32_BOUNDARY);
 128 #endif
 129
 130 static int sysctl_vm_phys_free(SYSCTL_HANDLER_ARGS);
 131 SYSCTL_OID(_vm, OID_AUTO, phys_free, CTLTYPE_STRING | CTLFLAG_RD,
 132     NULL, 0, sysctl_vm_phys_free, "A", "Phys Free Info");
 133
 134 static int sysctl_vm_phys_segs(SYSCTL_HANDLER_ARGS);
 135 SYSCTL_OID(_vm, OID_AUTO, phys_segs, CTLTYPE_STRING | CTLFLAG_RD,
 136     NULL, 0, sysctl_vm_phys_segs, "A", "Phys Seg Info");
 137
 138 #ifdef NUMA
 139 static int sysctl_vm_phys_locality(SYSCTL_HANDLER_ARGS);
 140 SYSCTL_OID(_vm, OID_AUTO, phys_locality, CTLTYPE_STRING | CTLFLAG_RD,
 141     NULL, 0, sysctl_vm_phys_locality, "A", "Phys Locality Info");
 142 #endif
 143
 144 SYSCTL_INT(_vm, OID_AUTO, ndomains, CTLFLAG_RD,
 145     &vm_ndomains, 0, "Number of physical memory domains available.");
 146
 147 static vm_page_t vm_phys_alloc_seg_contig(struct vm_phys_seg *seg,
 148     u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment,
 149     vm_paddr_t boundary);
 150 static void _vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int domain);
 151 static void vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end);
 152 static void vm_phys_split_pages(vm_page_t m, int oind, struct vm_freelist *fl,
 153     int order, int tail);
 154
 155 /*
 156  * Red-black tree helpers for vm fictitious range management.
 157  */
 158 static inline int
 159 vm_phys_fictitious_in_range(struct vm_phys_fictitious_seg *p,
 160     struct vm_phys_fictitious_seg *range)
 161 {
 162
 163         KASSERT(range->start != 0 && range->end != 0,
 164             ("Invalid range passed on search for vm_fictitious page"));
 165         if (p->start >= range->end)
 166                 return (1);
 167         if (p->start < range->start)
 168                 return (-1);
 169
 170         return (0);
 171 }
 172
 173 static int
 174 vm_phys_fictitious_cmp(struct vm_phys_fictitious_seg *p1,
 175     struct vm_phys_fictitious_seg *p2)
 176 {
 177
 178         /* Check if this is a search for a page */
 179         if (p1->end == 0)
 180                 return (vm_phys_fictitious_in_range(p1, p2));
 181
 182         KASSERT(p2->end != 0,
 183     ("Invalid range passed as second parameter to vm fictitious comparison"));
 184
 185         /* Searching to add a new range */
 186         if (p1->end <= p2->start)
 187                 return (-1);
 188         if (p1->start >= p2->end)
 189                 return (1);
 190
 191         panic("Trying to add overlapping vm fictitious ranges:\n"
 192             "[%#jx:%#jx] and [%#jx:%#jx]", (uintmax_t)p1->start,
 193             (uintmax_t)p1->end, (uintmax_t)p2->start, (uintmax_t)p2->end);
 194 }
 195
 196 int
 197 vm_phys_domain_match(int prefer, vm_paddr_t low, vm_paddr_t high)
 198 {
 199 #ifdef NUMA
 200         domainset_t mask;
 201         int i;
 202
 203         if (vm_ndomains == 1 || mem_affinity == NULL)
 204                 return (0);
 205
 206         DOMAINSET_ZERO(&mask);
 207         /*
 208          * Check for any memory that overlaps low, high.
 209          */
 210         for (i = 0; mem_affinity[i].end != 0; i++)
 211                 if (mem_affinity[i].start <= high &&
 212                     mem_affinity[i].end >= low)
 213                         DOMAINSET_SET(mem_affinity[i].domain, &mask);
 214         if (prefer != -1 && DOMAINSET_ISSET(prefer, &mask))
 215                 return (prefer);
 216         if (DOMAINSET_EMPTY(&mask))
 217                 panic("vm_phys_domain_match:  Impossible constraint");
 218         return (DOMAINSET_FFS(&mask) - 1);
 219 #else
 220         return (0);
 221 #endif
 222 }
 223
 224 /*
 225  * Outputs the state of the physical memory allocator, specifically,
 226  * the amount of physical memory in each free list.
 227  */
 228 static int
 229 sysctl_vm_phys_free(SYSCTL_HANDLER_ARGS)
 230 {
 231         struct sbuf sbuf;
 232         struct vm_freelist *fl;
 233         int dom, error, flind, oind, pind;
 234
 235         error = sysctl_wire_old_buffer(req, 0);
 236         if (error != 0)
 237                 return (error);
 238         sbuf_new_for_sysctl(&sbuf, NULL, 128 * vm_ndomains, req);
 239         for (dom = 0; dom < vm_ndomains; dom++) {
 240                 sbuf_printf(&sbuf,"\nDOMAIN %d:\n", dom);
 241                 for (flind = 0; flind < vm_nfreelists; flind++) {
 242                         sbuf_printf(&sbuf, "\nFREE LIST %d:\n"
 243                             "\n  ORDER (SIZE)  |  NUMBER"
 244                             "\n              ", flind);
 245                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
 246                                 sbuf_printf(&sbuf, "  |  POOL %d", pind);
 247                         sbuf_printf(&sbuf, "\n--            ");
 248                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
 249                                 sbuf_printf(&sbuf, "-- --      ");
 250                         sbuf_printf(&sbuf, "--\n");
 251                         for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
 252                                 sbuf_printf(&sbuf, "  %2d (%6dK)", oind,
 253                                     1 << (PAGE_SHIFT - 10 + oind));
 254                                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 255                                 fl = vm_phys_free_queues[dom][flind][pind];
 256                                         sbuf_printf(&sbuf, "  |  %6d",
 257                                             fl[oind].lcnt);
 258                                 }
 259                                 sbuf_printf(&sbuf, "\n");
 260                         }
 261                 }
 262         }
 263         error = sbuf_finish(&sbuf);
 264         sbuf_delete(&sbuf);
 265         return (error);
 266 }
 267
 268 /*
 269  * Outputs the set of physical memory segments.
 270  */
 271 static int
 272 sysctl_vm_phys_segs(SYSCTL_HANDLER_ARGS)
 273 {
 274         struct sbuf sbuf;
 275         struct vm_phys_seg *seg;
 276         int error, segind;
 277
 278         error = sysctl_wire_old_buffer(req, 0);
 279         if (error != 0)
 280                 return (error);
 281         sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
 282         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 283                 sbuf_printf(&sbuf, "\nSEGMENT %d:\n\n", segind);
 284                 seg = &vm_phys_segs[segind];
 285                 sbuf_printf(&sbuf, "start:     %#jx\n",
 286                     (uintmax_t)seg->start);
 287                 sbuf_printf(&sbuf, "end:       %#jx\n",
 288                     (uintmax_t)seg->end);
 289                 sbuf_printf(&sbuf, "domain:    %d\n", seg->domain);
 290                 sbuf_printf(&sbuf, "free list: %p\n", seg->free_queues);
 291         }
 292         error = sbuf_finish(&sbuf);
 293         sbuf_delete(&sbuf);
 294         return (error);
 295 }
 296
 297 /*
 298  * Return affinity, or -1 if there's no affinity information.
 299  */
 300 int
 301 vm_phys_mem_affinity(int f, int t)
 302 {
 303
 304 #ifdef NUMA
 305         if (mem_locality == NULL)
 306                 return (-1);
 307         if (f >= vm_ndomains || t >= vm_ndomains)
 308                 return (-1);
 309         return (mem_locality[f * vm_ndomains + t]);
 310 #else
 311         return (-1);
 312 #endif
 313 }
 314
 315 #ifdef NUMA
 316 /*
 317  * Outputs the VM locality table.
 318  */
 319 static int
 320 sysctl_vm_phys_locality(SYSCTL_HANDLER_ARGS)
 321 {
 322         struct sbuf sbuf;
 323         int error, i, j;
 324
 325         error = sysctl_wire_old_buffer(req, 0);
 326         if (error != 0)
 327                 return (error);
 328         sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
 329
 330         sbuf_printf(&sbuf, "\n");
 331
 332         for (i = 0; i < vm_ndomains; i++) {
 333                 sbuf_printf(&sbuf, "%d: ", i);
 334                 for (j = 0; j < vm_ndomains; j++) {
 335                         sbuf_printf(&sbuf, "%d ", vm_phys_mem_affinity(i, j));
 336                 }
 337                 sbuf_printf(&sbuf, "\n");
 338         }
 339         error = sbuf_finish(&sbuf);
 340         sbuf_delete(&sbuf);
 341         return (error);
 342 }
 343 #endif
 344
 345 static void
 346 vm_freelist_add(struct vm_freelist *fl, vm_page_t m, int order, int tail)
 347 {
 348
 349         m->order = order;
 350         if (tail)
 351                 TAILQ_INSERT_TAIL(&fl[order].pl, m, listq);
 352         else
 353                 TAILQ_INSERT_HEAD(&fl[order].pl, m, listq);
 354         fl[order].lcnt++;
 355 }
 356
 357 static void
 358 vm_freelist_rem(struct vm_freelist *fl, vm_page_t m, int order)
 359 {
 360
 361         TAILQ_REMOVE(&fl[order].pl, m, listq);
 362         fl[order].lcnt--;
 363         m->order = VM_NFREEORDER;
 364 }
 365
 366 /*
 367  * Create a physical memory segment.
 368  */
 369 static void
 370 _vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int domain)
 371 {
 372         struct vm_phys_seg *seg;
 373
 374         KASSERT(vm_phys_nsegs < VM_PHYSSEG_MAX,
 375             ("vm_phys_create_seg: increase VM_PHYSSEG_MAX"));
 376         KASSERT(domain >= 0 && domain < vm_ndomains,
 377             ("vm_phys_create_seg: invalid domain provided"));
 378         seg = &vm_phys_segs[vm_phys_nsegs++];
 379         while (seg > vm_phys_segs && (seg - 1)->start >= end) {
 380                 *seg = *(seg - 1);
 381                 seg--;
 382         }
 383         seg->start = start;
 384         seg->end = end;
 385         seg->domain = domain;
 386 }
 387
 388 static void
 389 vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end)
 390 {
 391 #ifdef NUMA
 392         int i;
 393
 394         if (mem_affinity == NULL) {
 395                 _vm_phys_create_seg(start, end, 0);
 396                 return;
 397         }
 398
 399         for (i = 0;; i++) {
 400                 if (mem_affinity[i].end == 0)
 401                         panic("Reached end of affinity info");
 402                 if (mem_affinity[i].end <= start)
 403                         continue;
 404                 if (mem_affinity[i].start > start)
 405                         panic("No affinity info for start %jx",
 406                             (uintmax_t)start);
 407                 if (mem_affinity[i].end >= end) {
 408                         _vm_phys_create_seg(start, end,
 409                             mem_affinity[i].domain);
 410                         break;
 411                 }
 412                 _vm_phys_create_seg(start, mem_affinity[i].end,
 413                     mem_affinity[i].domain);
 414                 start = mem_affinity[i].end;
 415         }
 416 #else
 417         _vm_phys_create_seg(start, end, 0);
 418 #endif
 419 }
 420
 421 /*
 422  * Add a physical memory segment.
 423  */
 424 void
 425 vm_phys_add_seg(vm_paddr_t start, vm_paddr_t end)
 426 {
 427         vm_paddr_t paddr;
 428
 429         KASSERT((start & PAGE_MASK) == 0,
 430             ("vm_phys_define_seg: start is not page aligned"));
 431         KASSERT((end & PAGE_MASK) == 0,
 432             ("vm_phys_define_seg: end is not page aligned"));
 433
 434         /*
 435          * Split the physical memory segment if it spans two or more free
 436          * list boundaries.
 437          */
 438         paddr = start;
 439 #ifdef  VM_FREELIST_LOWMEM
 440         if (paddr < VM_LOWMEM_BOUNDARY && end > VM_LOWMEM_BOUNDARY) {
 441                 vm_phys_create_seg(paddr, VM_LOWMEM_BOUNDARY);
 442                 paddr = VM_LOWMEM_BOUNDARY;
 443         }
 444 #endif
 445 #ifdef  VM_FREELIST_DMA32
 446         if (paddr < VM_DMA32_BOUNDARY && end > VM_DMA32_BOUNDARY) {
 447                 vm_phys_create_seg(paddr, VM_DMA32_BOUNDARY);
 448                 paddr = VM_DMA32_BOUNDARY;
 449         }
 450 #endif
 451         vm_phys_create_seg(paddr, end);
 452 }
 453
 454 /*
 455  * Initialize the physical memory allocator.
 456  *
 457  * Requires that vm_page_array is initialized!
 458  */
 459 void
 460 vm_phys_init(void)
 461 {
 462         struct vm_freelist *fl;
 463         struct vm_phys_seg *seg;
 464         u_long npages;
 465         int dom, flind, freelist, oind, pind, segind;
 466
 467         /*
 468          * Compute the number of free lists, and generate the mapping from the
 469          * manifest constants VM_FREELIST_* to the free list indices.
 470          *
 471          * Initially, the entries of vm_freelist_to_flind[] are set to either
 472          * 0 or 1 to indicate which free lists should be created.
 473          */
 474         npages = 0;
 475         for (segind = vm_phys_nsegs - 1; segind >= 0; segind--) {
 476                 seg = &vm_phys_segs[segind];
 477 #ifdef  VM_FREELIST_LOWMEM
 478                 if (seg->end <= VM_LOWMEM_BOUNDARY)
 479                         vm_freelist_to_flind[VM_FREELIST_LOWMEM] = 1;
 480                 else
 481 #endif
 482 #ifdef  VM_FREELIST_DMA32
 483                 if (
 484 #ifdef  VM_DMA32_NPAGES_THRESHOLD
 485                     /*
 486                      * Create the DMA32 free list only if the amount of
 487                      * physical memory above physical address 4G exceeds the
 488                      * given threshold.
 489                      */
 490                     npages > VM_DMA32_NPAGES_THRESHOLD &&
 491 #endif
 492                     seg->end <= VM_DMA32_BOUNDARY)
 493                         vm_freelist_to_flind[VM_FREELIST_DMA32] = 1;
 494                 else
 495 #endif
 496                 {
 497                         npages += atop(seg->end - seg->start);
 498                         vm_freelist_to_flind[VM_FREELIST_DEFAULT] = 1;
 499                 }
 500         }
 501         /* Change each entry into a running total of the free lists. */
 502         for (freelist = 1; freelist < VM_NFREELIST; freelist++) {
 503                 vm_freelist_to_flind[freelist] +=
 504                     vm_freelist_to_flind[freelist - 1];
 505         }
 506         vm_nfreelists = vm_freelist_to_flind[VM_NFREELIST - 1];
 507         KASSERT(vm_nfreelists > 0, ("vm_phys_init: no free lists"));
 508         /* Change each entry into a free list index. */
 509         for (freelist = 0; freelist < VM_NFREELIST; freelist++)
 510                 vm_freelist_to_flind[freelist]--;
 511
 512         /*
 513          * Initialize the first_page and free_queues fields of each physical
 514          * memory segment.
 515          */
 516 #ifdef VM_PHYSSEG_SPARSE
 517         npages = 0;
 518 #endif
 519         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 520                 seg = &vm_phys_segs[segind];
 521 #ifdef VM_PHYSSEG_SPARSE
 522                 seg->first_page = &vm_page_array[npages];
 523                 npages += atop(seg->end - seg->start);
 524 #else
 525                 seg->first_page = PHYS_TO_VM_PAGE(seg->start);
 526 #endif
 527 #ifdef  VM_FREELIST_LOWMEM
 528                 if (seg->end <= VM_LOWMEM_BOUNDARY) {
 529                         flind = vm_freelist_to_flind[VM_FREELIST_LOWMEM];
 530                         KASSERT(flind >= 0,
 531                             ("vm_phys_init: LOWMEM flind < 0"));
 532                 } else
 533 #endif
 534 #ifdef  VM_FREELIST_DMA32
 535                 if (seg->end <= VM_DMA32_BOUNDARY) {
 536                         flind = vm_freelist_to_flind[VM_FREELIST_DMA32];
 537                         KASSERT(flind >= 0,
 538                             ("vm_phys_init: DMA32 flind < 0"));
 539                 } else
 540 #endif
 541                 {
 542                         flind = vm_freelist_to_flind[VM_FREELIST_DEFAULT];
 543                         KASSERT(flind >= 0,
 544                             ("vm_phys_init: DEFAULT flind < 0"));
 545                 }
 546                 seg->free_queues = &vm_phys_free_queues[seg->domain][flind];
 547         }
 548
 549         /*
 550          * Initialize the free queues.
 551          */
 552         for (dom = 0; dom < vm_ndomains; dom++) {
 553                 for (flind = 0; flind < vm_nfreelists; flind++) {
 554                         for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 555                                 fl = vm_phys_free_queues[dom][flind][pind];
 556                                 for (oind = 0; oind < VM_NFREEORDER; oind++)
 557                                         TAILQ_INIT(&fl[oind].pl);
 558                         }
 559                 }
 560         }
 561
 562         rw_init(&vm_phys_fictitious_reg_lock, "vmfctr");
 563 }
 564
 565 /*
 566  * Split a contiguous, power of two-sized set of physical pages.
 567  *
 568  * When this function is called by a page allocation function, the caller
 569  * should request insertion at the head unless the order [order, oind) queues
 570  * are known to be empty.  The objective being to reduce the likelihood of
 571  * long-term fragmentation by promoting contemporaneous allocation and
 572  * (hopefully) deallocation.
 573  */
 574 static __inline void
 575 vm_phys_split_pages(vm_page_t m, int oind, struct vm_freelist *fl, int order,
 576     int tail)
 577 {
 578         vm_page_t m_buddy;
 579
 580         while (oind > order) {
 581                 oind--;
 582                 m_buddy = &m[1 << oind];
 583                 KASSERT(m_buddy->order == VM_NFREEORDER,
 584                     ("vm_phys_split_pages: page %p has unexpected order %d",
 585                     m_buddy, m_buddy->order));
 586                 vm_freelist_add(fl, m_buddy, oind, tail);
 587         }
 588 }
 589
 590 /*
 591  * Add the physical pages [m, m + npages) at the end of a power-of-two aligned
 592  * and sized set to the specified free list.
 593  *
 594  * When this function is called by a page allocation function, the caller
 595  * should request insertion at the head unless the lower-order queues are
 596  * known to be empty.  The objective being to reduce the likelihood of long-
 597  * term fragmentation by promoting contemporaneous allocation and (hopefully)
 598  * deallocation.
 599  *
 600  * The physical page m's buddy must not be free.
 601  */
 602 static void
 603 vm_phys_enq_range(vm_page_t m, u_int npages, struct vm_freelist *fl, int tail)
 604 {
 605         u_int n;
 606         int order;
 607
 608         KASSERT(npages > 0, ("vm_phys_enq_range: npages is 0"));
 609         KASSERT(((VM_PAGE_TO_PHYS(m) + npages * PAGE_SIZE) &
 610             ((PAGE_SIZE << (fls(npages) - 1)) - 1)) == 0,
 611             ("vm_phys_enq_range: page %p and npages %u are misaligned",
 612             m, npages));
 613         do {
 614                 KASSERT(m->order == VM_NFREEORDER,
 615                     ("vm_phys_enq_range: page %p has unexpected order %d",
 616                     m, m->order));
 617                 order = ffs(npages) - 1;
 618                 KASSERT(order < VM_NFREEORDER,
 619                     ("vm_phys_enq_range: order %d is out of range", order));
 620                 vm_freelist_add(fl, m, order, tail);
 621                 n = 1 << order;
 622                 m += n;
 623                 npages -= n;
 624         } while (npages > 0);
 625 }
 626
 627 /*
 628  * Tries to allocate the specified number of pages from the specified pool
 629  * within the specified domain.  Returns the actual number of allocated pages
 630  * and a pointer to each page through the array ma[].
 631  *
 632  * The returned pages may not be physically contiguous.  However, in contrast
 633  * to performing multiple, back-to-back calls to vm_phys_alloc_pages(..., 0),
 634  * calling this function once to allocate the desired number of pages will
 635  * avoid wasted time in vm_phys_split_pages().
 636  *
 637  * The free page queues for the specified domain must be locked.
 638  */
 639 int
 640 vm_phys_alloc_npages(int domain, int pool, int npages, vm_page_t ma[])
 641 {
 642         struct vm_freelist *alt, *fl;
 643         vm_page_t m;
 644         int avail, end, flind, freelist, i, need, oind, pind;
 645
 646         KASSERT(domain >= 0 && domain < vm_ndomains,
 647             ("vm_phys_alloc_npages: domain %d is out of range", domain));
 648         KASSERT(pool < VM_NFREEPOOL,
 649             ("vm_phys_alloc_npages: pool %d is out of range", pool));
 650         KASSERT(npages <= 1 << (VM_NFREEORDER - 1),
 651             ("vm_phys_alloc_npages: npages %d is out of range", npages));
 652         vm_domain_free_assert_locked(VM_DOMAIN(domain));
 653         i = 0;
 654         for (freelist = 0; freelist < VM_NFREELIST; freelist++) {
 655                 flind = vm_freelist_to_flind[freelist];
 656                 if (flind < 0)
 657                         continue;
 658                 fl = vm_phys_free_queues[domain][flind][pool];
 659                 for (oind = 0; oind < VM_NFREEORDER; oind++) {
 660                         while ((m = TAILQ_FIRST(&fl[oind].pl)) != NULL) {
 661                                 vm_freelist_rem(fl, m, oind);
 662                                 avail = 1 << oind;
 663                                 need = imin(npages - i, avail);
 664                                 for (end = i + need; i < end;)
 665                                         ma[i++] = m++;
 666                                 if (need < avail) {
 667                                         /*
 668                                          * Return excess pages to fl.  Its
 669                                          * order [0, oind) queues are empty.
 670                                          */
 671                                         vm_phys_enq_range(m, avail - need, fl,
 672                                             1);
 673                                         return (npages);
 674                                 } else if (i == npages)
 675                                         return (npages);
 676                         }
 677                 }
 678                 for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
 679                         for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 680                                 alt = vm_phys_free_queues[domain][flind][pind];
 681                                 while ((m = TAILQ_FIRST(&alt[oind].pl)) !=
 682                                     NULL) {
 683                                         vm_freelist_rem(alt, m, oind);
 684                                         vm_phys_set_pool(pool, m, oind);
 685                                         avail = 1 << oind;
 686                                         need = imin(npages - i, avail);
 687                                         for (end = i + need; i < end;)
 688                                                 ma[i++] = m++;
 689                                         if (need < avail) {
 690                                                 /*
 691                                                  * Return excess pages to fl.
 692                                                  * Its order [0, oind) queues
 693                                                  * are empty.
 694                                                  */
 695                                                 vm_phys_enq_range(m, avail -
 696                                                     need, fl, 1);
 697                                                 return (npages);
 698                                         } else if (i == npages)
 699                                                 return (npages);
 700                                 }
 701                         }
 702                 }
 703         }
 704         return (i);
 705 }
 706
 707 /*
 708  * Allocate a contiguous, power of two-sized set of physical pages
 709  * from the free lists.
 710  *
 711  * The free page queues must be locked.
 712  */
 713 vm_page_t
 714 vm_phys_alloc_pages(int domain, int pool, int order)
 715 {
 716         vm_page_t m;
 717         int freelist;
 718
 719         for (freelist = 0; freelist < VM_NFREELIST; freelist++) {
 720                 m = vm_phys_alloc_freelist_pages(domain, freelist, pool, order);
 721                 if (m != NULL)
 722                         return (m);
 723         }
 724         return (NULL);
 725 }
 726
 727 /*
 728  * Allocate a contiguous, power of two-sized set of physical pages from the
 729  * specified free list.  The free list must be specified using one of the
 730  * manifest constants VM_FREELIST_*.
 731  *
 732  * The free page queues must be locked.
 733  */
 734 vm_page_t
 735 vm_phys_alloc_freelist_pages(int domain, int freelist, int pool, int order)
 736 {
 737         struct vm_freelist *alt, *fl;
 738         vm_page_t m;
 739         int oind, pind, flind;
 740
 741         KASSERT(domain >= 0 && domain < vm_ndomains,
 742             ("vm_phys_alloc_freelist_pages: domain %d is out of range",
 743             domain));
 744         KASSERT(freelist < VM_NFREELIST,
 745             ("vm_phys_alloc_freelist_pages: freelist %d is out of range",
 746             freelist));
 747         KASSERT(pool < VM_NFREEPOOL,
 748             ("vm_phys_alloc_freelist_pages: pool %d is out of range", pool));
 749         KASSERT(order < VM_NFREEORDER,
 750             ("vm_phys_alloc_freelist_pages: order %d is out of range", order));
 751
 752         flind = vm_freelist_to_flind[freelist];
 753         /* Check if freelist is present */
 754         if (flind < 0)
 755                 return (NULL);
 756
 757         vm_domain_free_assert_locked(VM_DOMAIN(domain));
 758         fl = &vm_phys_free_queues[domain][flind][pool][0];
 759         for (oind = order; oind < VM_NFREEORDER; oind++) {
 760                 m = TAILQ_FIRST(&fl[oind].pl);
 761                 if (m != NULL) {
 762                         vm_freelist_rem(fl, m, oind);
 763                         /* The order [order, oind) queues are empty. */
 764                         vm_phys_split_pages(m, oind, fl, order, 1);
 765                         return (m);
 766                 }
 767         }
 768
 769         /*
 770          * The given pool was empty.  Find the largest
 771          * contiguous, power-of-two-sized set of pages in any
 772          * pool.  Transfer these pages to the given pool, and
 773          * use them to satisfy the allocation.
 774          */
 775         for (oind = VM_NFREEORDER - 1; oind >= order; oind--) {
 776                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 777                         alt = &vm_phys_free_queues[domain][flind][pind][0];
 778                         m = TAILQ_FIRST(&alt[oind].pl);
 779                         if (m != NULL) {
 780                                 vm_freelist_rem(alt, m, oind);
 781                                 vm_phys_set_pool(pool, m, oind);
 782                                 /* The order [order, oind) queues are empty. */
 783                                 vm_phys_split_pages(m, oind, fl, order, 1);
 784                                 return (m);
 785                         }
 786                 }
 787         }
 788         return (NULL);
 789 }
 790
 791 /*
 792  * Find the vm_page corresponding to the given physical address.
 793  */
 794 vm_page_t
 795 vm_phys_paddr_to_vm_page(vm_paddr_t pa)
 796 {
 797         struct vm_phys_seg *seg;
 798         int segind;
 799
 800         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 801                 seg = &vm_phys_segs[segind];
 802                 if (pa >= seg->start && pa < seg->end)
 803                         return (&seg->first_page[atop(pa - seg->start)]);
 804         }
 805         return (NULL);
 806 }
 807
 808 vm_page_t
 809 vm_phys_fictitious_to_vm_page(vm_paddr_t pa)
 810 {
 811         struct vm_phys_fictitious_seg tmp, *seg;
 812         vm_page_t m;
 813
 814         m = NULL;
 815         tmp.start = pa;
 816         tmp.end = 0;
 817
 818         rw_rlock(&vm_phys_fictitious_reg_lock);
 819         seg = RB_FIND(fict_tree, &vm_phys_fictitious_tree, &tmp);
 820         rw_runlock(&vm_phys_fictitious_reg_lock);
 821         if (seg == NULL)
 822                 return (NULL);
 823
 824         m = &seg->first_page[atop(pa - seg->start)];
 825         KASSERT((m->flags & PG_FICTITIOUS) != 0, ("%p not fictitious", m));
 826
 827         return (m);
 828 }
 829
 830 static inline void
 831 vm_phys_fictitious_init_range(vm_page_t range, vm_paddr_t start,
 832     long page_count, vm_memattr_t memattr)
 833 {
 834         long i;
 835
 836         bzero(range, page_count * sizeof(*range));
 837         for (i = 0; i < page_count; i++) {
 838                 vm_page_initfake(&range[i], start + PAGE_SIZE * i, memattr);
 839                 range[i].oflags &= ~VPO_UNMANAGED;
 840                 range[i].busy_lock = VPB_UNBUSIED;
 841         }
 842 }
 843
 844 int
 845 vm_phys_fictitious_reg_range(vm_paddr_t start, vm_paddr_t end,
 846     vm_memattr_t memattr)
 847 {
 848         struct vm_phys_fictitious_seg *seg;
 849         vm_page_t fp;
 850         long page_count;
 851 #ifdef VM_PHYSSEG_DENSE
 852         long pi, pe;
 853         long dpage_count;
 854 #endif
 855
 856         KASSERT(start < end,
 857             ("Start of segment isn't less than end (start: %jx end: %jx)",
 858             (uintmax_t)start, (uintmax_t)end));
 859
 860         page_count = (end - start) / PAGE_SIZE;
 861
 862 #ifdef VM_PHYSSEG_DENSE
 863         pi = atop(start);
 864         pe = atop(end);
 865         if (pi >= first_page && (pi - first_page) < vm_page_array_size) {
 866                 fp = &vm_page_array[pi - first_page];
 867                 if ((pe - first_page) > vm_page_array_size) {
 868                         /*
 869                          * We have a segment that starts inside
 870                          * of vm_page_array, but ends outside of it.
 871                          *
 872                          * Use vm_page_array pages for those that are
 873                          * inside of the vm_page_array range, and
 874                          * allocate the remaining ones.
 875                          */
 876                         dpage_count = vm_page_array_size - (pi - first_page);
 877                         vm_phys_fictitious_init_range(fp, start, dpage_count,
 878                             memattr);
 879                         page_count -= dpage_count;
 880                         start += ptoa(dpage_count);
 881                         goto alloc;
 882                 }
 883                 /*
 884                  * We can allocate the full range from vm_page_array,
 885                  * so there's no need to register the range in the tree.
 886                  */
 887                 vm_phys_fictitious_init_range(fp, start, page_count, memattr);
 888                 return (0);
 889         } else if (pe > first_page && (pe - first_page) < vm_page_array_size) {
 890                 /*
 891                  * We have a segment that ends inside of vm_page_array,
 892                  * but starts outside of it.
 893                  */
 894                 fp = &vm_page_array[0];
 895                 dpage_count = pe - first_page;
 896                 vm_phys_fictitious_init_range(fp, ptoa(first_page), dpage_count,
 897                     memattr);
 898                 end -= ptoa(dpage_count);
 899                 page_count -= dpage_count;
 900                 goto alloc;
 901         } else if (pi < first_page && pe > (first_page + vm_page_array_size)) {
 902                 /*
 903                  * Trying to register a fictitious range that expands before
 904                  * and after vm_page_array.
 905                  */
 906                 return (EINVAL);
 907         } else {
 908 alloc:
 909 #endif
 910                 fp = malloc(page_count * sizeof(struct vm_page), M_FICT_PAGES,
 911                     M_WAITOK);
 912 #ifdef VM_PHYSSEG_DENSE
 913         }
 914 #endif
 915         vm_phys_fictitious_init_range(fp, start, page_count, memattr);
 916
 917         seg = malloc(sizeof(*seg), M_FICT_PAGES, M_WAITOK | M_ZERO);
 918         seg->start = start;
 919         seg->end = end;
 920         seg->first_page = fp;
 921
 922         rw_wlock(&vm_phys_fictitious_reg_lock);
 923         RB_INSERT(fict_tree, &vm_phys_fictitious_tree, seg);
 924         rw_wunlock(&vm_phys_fictitious_reg_lock);
 925
 926         return (0);
 927 }
 928
 929 void
 930 vm_phys_fictitious_unreg_range(vm_paddr_t start, vm_paddr_t end)
 931 {
 932         struct vm_phys_fictitious_seg *seg, tmp;
 933 #ifdef VM_PHYSSEG_DENSE
 934         long pi, pe;
 935 #endif
 936
 937         KASSERT(start < end,
 938             ("Start of segment isn't less than end (start: %jx end: %jx)",
 939             (uintmax_t)start, (uintmax_t)end));
 940
 941 #ifdef VM_PHYSSEG_DENSE
 942         pi = atop(start);
 943         pe = atop(end);
 944         if (pi >= first_page && (pi - first_page) < vm_page_array_size) {
 945                 if ((pe - first_page) <= vm_page_array_size) {
 946                         /*
 947                          * This segment was allocated using vm_page_array
 948                          * only, there's nothing to do since those pages
 949                          * were never added to the tree.
 950                          */
 951                         return;
 952                 }
 953                 /*
 954                  * We have a segment that starts inside
 955                  * of vm_page_array, but ends outside of it.
 956                  *
 957                  * Calculate how many pages were added to the
 958                  * tree and free them.
 959                  */
 960                 start = ptoa(first_page + vm_page_array_size);
 961         } else if (pe > first_page && (pe - first_page) < vm_page_array_size) {
 962                 /*
 963                  * We have a segment that ends inside of vm_page_array,
 964                  * but starts outside of it.
 965                  */
 966                 end = ptoa(first_page);
 967         } else if (pi < first_page && pe > (first_page + vm_page_array_size)) {
 968                 /* Since it's not possible to register such a range, panic. */
 969                 panic(
 970                     "Unregistering not registered fictitious range [%#jx:%#jx]",
 971                     (uintmax_t)start, (uintmax_t)end);
 972         }
 973 #endif
 974         tmp.start = start;
 975         tmp.end = 0;
 976
 977         rw_wlock(&vm_phys_fictitious_reg_lock);
 978         seg = RB_FIND(fict_tree, &vm_phys_fictitious_tree, &tmp);
 979         if (seg->start != start || seg->end != end) {
 980                 rw_wunlock(&vm_phys_fictitious_reg_lock);
 981                 panic(
 982                     "Unregistering not registered fictitious range [%#jx:%#jx]",
 983                     (uintmax_t)start, (uintmax_t)end);
 984         }
 985         RB_REMOVE(fict_tree, &vm_phys_fictitious_tree, seg);
 986         rw_wunlock(&vm_phys_fictitious_reg_lock);
 987         free(seg->first_page, M_FICT_PAGES);
 988         free(seg, M_FICT_PAGES);
 989 }
 990
 991 /*
 992  * Free a contiguous, power of two-sized set of physical pages.
 993  *
 994  * The free page queues must be locked.
 995  */
 996 void
 997 vm_phys_free_pages(vm_page_t m, int order)
 998 {
 999         struct vm_freelist *fl;
1000         struct vm_phys_seg *seg;
1001         vm_paddr_t pa;
1002         vm_page_t m_buddy;
1003
1004         KASSERT(m->order == VM_NFREEORDER,
1005             ("vm_phys_free_pages: page %p has unexpected order %d",
1006             m, m->order));
1007         KASSERT(m->pool < VM_NFREEPOOL,
1008             ("vm_phys_free_pages: page %p has unexpected pool %d",
1009             m, m->pool));
1010         KASSERT(order < VM_NFREEORDER,
1011             ("vm_phys_free_pages: order %d is out of range", order));
1012         seg = &vm_phys_segs[m->segind];
1013         vm_domain_free_assert_locked(VM_DOMAIN(seg->domain));
1014         if (order < VM_NFREEORDER - 1) {
1015                 pa = VM_PAGE_TO_PHYS(m);
1016                 do {
1017                         pa ^= ((vm_paddr_t)1 << (PAGE_SHIFT + order));
1018                         if (pa < seg->start || pa >= seg->end)
1019                                 break;
1020                         m_buddy = &seg->first_page[atop(pa - seg->start)];
1021                         if (m_buddy->order != order)
1022                                 break;
1023                         fl = (*seg->free_queues)[m_buddy->pool];
1024                         vm_freelist_rem(fl, m_buddy, order);
1025                         if (m_buddy->pool != m->pool)
1026                                 vm_phys_set_pool(m->pool, m_buddy, order);
1027                         order++;
1028                         pa &= ~(((vm_paddr_t)1 << (PAGE_SHIFT + order)) - 1);
1029                         m = &seg->first_page[atop(pa - seg->start)];
1030                 } while (order < VM_NFREEORDER - 1);
1031         }
1032         fl = (*seg->free_queues)[m->pool];
1033         vm_freelist_add(fl, m, order, 1);
1034 }
1035
1036 /*
1037  * Free a contiguous, arbitrarily sized set of physical pages.
1038  *
1039  * The free page queues must be locked.
1040  */
1041 void
1042 vm_phys_free_contig(vm_page_t m, u_long npages)
1043 {
1044         u_int n;
1045         int order;
1046
1047         /*
1048          * Avoid unnecessary coalescing by freeing the pages in the largest
1049          * possible power-of-two-sized subsets.
1050          */
1051         vm_domain_free_assert_locked(vm_pagequeue_domain(m));
1052         for (;; npages -= n) {
1053                 /*
1054                  * Unsigned "min" is used here so that "order" is assigned
1055                  * "VM_NFREEORDER - 1" when "m"'s physical address is zero
1056                  * or the low-order bits of its physical address are zero
1057                  * because the size of a physical address exceeds the size of
1058                  * a long.
1059                  */
1060                 order = min(ffsl(VM_PAGE_TO_PHYS(m) >> PAGE_SHIFT) - 1,
1061                     VM_NFREEORDER - 1);
1062                 n = 1 << order;
1063                 if (npages < n)
1064                         break;
1065                 vm_phys_free_pages(m, order);
1066                 m += n;
1067         }
1068         /* The residual "npages" is less than "1 << (VM_NFREEORDER - 1)". */
1069         for (; npages > 0; npages -= n) {
1070                 order = flsl(npages) - 1;
1071                 n = 1 << order;
1072                 vm_phys_free_pages(m, order);
1073                 m += n;
1074         }
1075 }
1076
1077 /*
1078  * Scan physical memory between the specified addresses "low" and "high" for a
1079  * run of contiguous physical pages that satisfy the specified conditions, and
1080  * return the lowest page in the run.  The specified "alignment" determines
1081  * the alignment of the lowest physical page in the run.  If the specified
1082  * "boundary" is non-zero, then the run of physical pages cannot span a
1083  * physical address that is a multiple of "boundary".
1084  *
1085  * "npages" must be greater than zero.  Both "alignment" and "boundary" must
1086  * be a power of two.
1087  */
1088 vm_page_t
1089 vm_phys_scan_contig(int domain, u_long npages, vm_paddr_t low, vm_paddr_t high,
1090     u_long alignment, vm_paddr_t boundary, int options)
1091 {
1092         vm_paddr_t pa_end;
1093         vm_page_t m_end, m_run, m_start;
1094         struct vm_phys_seg *seg;
1095         int segind;
1096
1097         KASSERT(npages > 0, ("npages is 0"));
1098         KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
1099         KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
1100         if (low >= high)
1101                 return (NULL);
1102         for (segind = 0; segind < vm_phys_nsegs; segind++) {
1103                 seg = &vm_phys_segs[segind];
1104                 if (seg->domain != domain)
1105                         continue;
1106                 if (seg->start >= high)
1107                         break;
1108                 if (low >= seg->end)
1109                         continue;
1110                 if (low <= seg->start)
1111                         m_start = seg->first_page;
1112                 else
1113                         m_start = &seg->first_page[atop(low - seg->start)];
1114                 if (high < seg->end)
1115                         pa_end = high;
1116                 else
1117                         pa_end = seg->end;
1118                 if (pa_end - VM_PAGE_TO_PHYS(m_start) < ptoa(npages))
1119                         continue;
1120                 m_end = &seg->first_page[atop(pa_end - seg->start)];
1121                 m_run = vm_page_scan_contig(npages, m_start, m_end,
1122                     alignment, boundary, options);
1123                 if (m_run != NULL)
1124                         return (m_run);
1125         }
1126         return (NULL);
1127 }
1128
1129 /*
1130  * Set the pool for a contiguous, power of two-sized set of physical pages.
1131  */
1132 void
1133 vm_phys_set_pool(int pool, vm_page_t m, int order)
1134 {
1135         vm_page_t m_tmp;
1136
1137         for (m_tmp = m; m_tmp < &m[1 << order]; m_tmp++)
1138                 m_tmp->pool = pool;
1139 }
1140
1141 /*
1142  * Search for the given physical page "m" in the free lists.  If the search
1143  * succeeds, remove "m" from the free lists and return TRUE.  Otherwise, return
1144  * FALSE, indicating that "m" is not in the free lists.
1145  *
1146  * The free page queues must be locked.
1147  */
1148 boolean_t
1149 vm_phys_unfree_page(vm_page_t m)
1150 {
1151         struct vm_freelist *fl;
1152         struct vm_phys_seg *seg;
1153         vm_paddr_t pa, pa_half;
1154         vm_page_t m_set, m_tmp;
1155         int order;
1156
1157         /*
1158          * First, find the contiguous, power of two-sized set of free
1159          * physical pages containing the given physical page "m" and
1160          * assign it to "m_set".
1161          */
1162         seg = &vm_phys_segs[m->segind];
1163         vm_domain_free_assert_locked(VM_DOMAIN(seg->domain));
1164         for (m_set = m, order = 0; m_set->order == VM_NFREEORDER &&
1165             order < VM_NFREEORDER - 1; ) {
1166                 order++;
1167                 pa = m->phys_addr & (~(vm_paddr_t)0 << (PAGE_SHIFT + order));
1168                 if (pa >= seg->start)
1169                         m_set = &seg->first_page[atop(pa - seg->start)];
1170                 else
1171                         return (FALSE);
1172         }
1173         if (m_set->order < order)
1174                 return (FALSE);
1175         if (m_set->order == VM_NFREEORDER)
1176                 return (FALSE);
1177         KASSERT(m_set->order < VM_NFREEORDER,
1178             ("vm_phys_unfree_page: page %p has unexpected order %d",
1179             m_set, m_set->order));
1180
1181         /*
1182          * Next, remove "m_set" from the free lists.  Finally, extract
1183          * "m" from "m_set" using an iterative algorithm: While "m_set"
1184          * is larger than a page, shrink "m_set" by returning the half
1185          * of "m_set" that does not contain "m" to the free lists.
1186          */
1187         fl = (*seg->free_queues)[m_set->pool];
1188         order = m_set->order;
1189         vm_freelist_rem(fl, m_set, order);
1190         while (order > 0) {
1191                 order--;
1192                 pa_half = m_set->phys_addr ^ (1 << (PAGE_SHIFT + order));
1193                 if (m->phys_addr < pa_half)
1194                         m_tmp = &seg->first_page[atop(pa_half - seg->start)];
1195                 else {
1196                         m_tmp = m_set;
1197                         m_set = &seg->first_page[atop(pa_half - seg->start)];
1198                 }
1199                 vm_freelist_add(fl, m_tmp, order, 0);
1200         }
1201         KASSERT(m_set == m, ("vm_phys_unfree_page: fatal inconsistency"));
1202         return (TRUE);
1203 }
1204
1205 /*
1206  * Allocate a contiguous set of physical pages of the given size
1207  * "npages" from the free lists.  All of the physical pages must be at
1208  * or above the given physical address "low" and below the given
1209  * physical address "high".  The given value "alignment" determines the
1210  * alignment of the first physical page in the set.  If the given value
1211  * "boundary" is non-zero, then the set of physical pages cannot cross
1212  * any physical address boundary that is a multiple of that value.  Both
1213  * "alignment" and "boundary" must be a power of two.
1214  */
1215 vm_page_t
1216 vm_phys_alloc_contig(int domain, u_long npages, vm_paddr_t low, vm_paddr_t high,
1217     u_long alignment, vm_paddr_t boundary)
1218 {
1219         vm_paddr_t pa_end, pa_start;
1220         vm_page_t m_run;
1221         struct vm_phys_seg *seg;
1222         int segind;
1223
1224         KASSERT(npages > 0, ("npages is 0"));
1225         KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
1226         KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
1227         vm_domain_free_assert_locked(VM_DOMAIN(domain));
1228         if (low >= high)
1229                 return (NULL);
1230         m_run = NULL;
1231         for (segind = vm_phys_nsegs - 1; segind >= 0; segind--) {
1232                 seg = &vm_phys_segs[segind];
1233                 if (seg->start >= high || seg->domain != domain)
1234                         continue;
1235                 if (low >= seg->end)
1236                         break;
1237                 if (low <= seg->start)
1238                         pa_start = seg->start;
1239                 else
1240                         pa_start = low;
1241                 if (high < seg->end)
1242                         pa_end = high;
1243                 else
1244                         pa_end = seg->end;
1245                 if (pa_end - pa_start < ptoa(npages))
1246                         continue;
1247                 m_run = vm_phys_alloc_seg_contig(seg, npages, low, high,
1248                     alignment, boundary);
1249                 if (m_run != NULL)
1250                         break;
1251         }
1252         return (m_run);
1253 }
1254
1255 /*
1256  * Allocate a run of contiguous physical pages from the free list for the
1257  * specified segment.
1258  */
1259 static vm_page_t
1260 vm_phys_alloc_seg_contig(struct vm_phys_seg *seg, u_long npages,
1261     vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary)
1262 {
1263         struct vm_freelist *fl;
1264         vm_paddr_t pa, pa_end, size;
1265         vm_page_t m, m_ret;
1266         u_long npages_end;
1267         int oind, order, pind;
1268
1269         KASSERT(npages > 0, ("npages is 0"));
1270         KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
1271         KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
1272         vm_domain_free_assert_locked(VM_DOMAIN(seg->domain));
1273         /* Compute the queue that is the best fit for npages. */
1274         order = flsl(npages - 1);
1275         /* Search for a run satisfying the specified conditions. */
1276         size = npages << PAGE_SHIFT;
1277         for (oind = min(order, VM_NFREEORDER - 1); oind < VM_NFREEORDER;
1278             oind++) {
1279                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
1280                         fl = (*seg->free_queues)[pind];
1281                         TAILQ_FOREACH(m_ret, &fl[oind].pl, listq) {
1282                                 /*
1283                                  * Is the size of this allocation request
1284                                  * larger than the largest block size?
1285                                  */
1286                                 if (order >= VM_NFREEORDER) {
1287                                         /*
1288                                          * Determine if a sufficient number of
1289                                          * subsequent blocks to satisfy the
1290                                          * allocation request are free.
1291                                          */
1292                                         pa = VM_PAGE_TO_PHYS(m_ret);
1293                                         pa_end = pa + size;
1294                                         if (pa_end < pa)
1295                                                 continue;
1296                                         for (;;) {
1297                                                 pa += 1 << (PAGE_SHIFT +
1298                                                     VM_NFREEORDER - 1);
1299                                                 if (pa >= pa_end ||
1300                                                     pa < seg->start ||
1301                                                     pa >= seg->end)
1302                                                         break;
1303                                                 m = &seg->first_page[atop(pa -
1304                                                     seg->start)];
1305                                                 if (m->order != VM_NFREEORDER -
1306                                                     1)
1307                                                         break;
1308                                         }
1309                                         /* If not, go to the next block. */
1310                                         if (pa < pa_end)
1311                                                 continue;
1312                                 }
1313
1314                                 /*
1315                                  * Determine if the blocks are within the
1316                                  * given range, satisfy the given alignment,
1317                                  * and do not cross the given boundary.
1318                                  */
1319                                 pa = VM_PAGE_TO_PHYS(m_ret);
1320                                 pa_end = pa + size;
1321                                 if (pa >= low && pa_end <= high &&
1322                                     (pa & (alignment - 1)) == 0 &&
1323                                     rounddown2(pa ^ (pa_end - 1), boundary) == 0)
1324                                         goto done;
1325                         }
1326                 }
1327         }
1328         return (NULL);
1329 done:
1330         for (m = m_ret; m < &m_ret[npages]; m = &m[1 << oind]) {
1331                 fl = (*seg->free_queues)[m->pool];
1332                 vm_freelist_rem(fl, m, oind);
1333                 if (m->pool != VM_FREEPOOL_DEFAULT)
1334                         vm_phys_set_pool(VM_FREEPOOL_DEFAULT, m, oind);
1335         }
1336         /* Return excess pages to the free lists. */
1337         npages_end = roundup2(npages, 1 << oind);
1338         if (npages < npages_end) {
1339                 fl = (*seg->free_queues)[VM_FREEPOOL_DEFAULT];
1340                 vm_phys_enq_range(&m_ret[npages], npages_end - npages, fl, 0);
1341         }
1342         return (m_ret);
1343 }
1344
1345 #ifdef DDB
1346 /*
1347  * Show the number of physical pages in each of the free lists.
1348  */
1349 DB_SHOW_COMMAND(freepages, db_show_freepages)
1350 {
1351         struct vm_freelist *fl;
1352         int flind, oind, pind, dom;
1353
1354         for (dom = 0; dom < vm_ndomains; dom++) {
1355                 db_printf("DOMAIN: %d\n", dom);
1356                 for (flind = 0; flind < vm_nfreelists; flind++) {
1357                         db_printf("FREE LIST %d:\n"
1358                             "\n  ORDER (SIZE)  |  NUMBER"
1359                             "\n              ", flind);
1360                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
1361                                 db_printf("  |  POOL %d", pind);
1362                         db_printf("\n--            ");
1363                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
1364                                 db_printf("-- --      ");
1365                         db_printf("--\n");
1366                         for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
1367                                 db_printf("  %2.2d (%6.6dK)", oind,
1368                                     1 << (PAGE_SHIFT - 10 + oind));
1369                                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
1370                                 fl = vm_phys_free_queues[dom][flind][pind];
1371                                         db_printf("  |  %6.6d", fl[oind].lcnt);
1372                                 }
1373                                 db_printf("\n");
1374                         }
1375                         db_printf("\n");
1376                 }
1377                 db_printf("\n");
1378         }
1379 }
1380 #endif