sys/vm/vm_phys.c

   1 /*-
   2  * Copyright (c) 2002-2006 Rice University
   3  * Copyright (c) 2007 Alan L. Cox <alc@cs.rice.edu>
   4  * All rights reserved.
   5  *
   6  * This software was developed for the FreeBSD Project by Alan L. Cox,
   7  * Olivier Crameri, Peter Druschel, Sitaram Iyer, and Juan Navarro.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  21  * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT
  22  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  24  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
  25  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  26  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
  28  * WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 /*
  33  *      Physical memory system implementation
  34  *
  35  * Any external functions defined by this module are only to be used by the
  36  * virtual memory system.
  37  */
  38
  39 #include <sys/cdefs.h>
  40 __FBSDID("$FreeBSD$");
  41
  42 #include "opt_ddb.h"
  43 #include "opt_vm.h"
  44
  45 #include <sys/param.h>
  46 #include <sys/systm.h>
  47 #include <sys/lock.h>
  48 #include <sys/kernel.h>
  49 #include <sys/malloc.h>
  50 #include <sys/mutex.h>
  51 #include <sys/proc.h>
  52 #include <sys/queue.h>
  53 #include <sys/rwlock.h>
  54 #include <sys/sbuf.h>
  55 #include <sys/sysctl.h>
  56 #include <sys/tree.h>
  57 #include <sys/vmmeter.h>
  58 #include <sys/seq.h>
  59
  60 #include <ddb/ddb.h>
  61
  62 #include <vm/vm.h>
  63 #include <vm/vm_param.h>
  64 #include <vm/vm_kern.h>
  65 #include <vm/vm_object.h>
  66 #include <vm/vm_page.h>
  67 #include <vm/vm_phys.h>
  68
  69 #include <vm/vm_domain.h>
  70
  71 _Static_assert(sizeof(long) * NBBY >= VM_PHYSSEG_MAX,
  72     "Too many physsegs.");
  73
  74 #ifdef VM_NUMA_ALLOC
  75 struct mem_affinity *mem_affinity;
  76 int *mem_locality;
  77 #endif
  78
  79 int vm_ndomains = 1;
  80
  81 struct vm_phys_seg vm_phys_segs[VM_PHYSSEG_MAX];
  82 int vm_phys_nsegs;
  83
  84 struct vm_phys_fictitious_seg;
  85 static int vm_phys_fictitious_cmp(struct vm_phys_fictitious_seg *,
  86     struct vm_phys_fictitious_seg *);
  87
  88 RB_HEAD(fict_tree, vm_phys_fictitious_seg) vm_phys_fictitious_tree =
  89     RB_INITIALIZER(_vm_phys_fictitious_tree);
  90
  91 struct vm_phys_fictitious_seg {
  92         RB_ENTRY(vm_phys_fictitious_seg) node;
  93         /* Memory region data */
  94         vm_paddr_t      start;
  95         vm_paddr_t      end;
  96         vm_page_t       first_page;
  97 };
  98
  99 RB_GENERATE_STATIC(fict_tree, vm_phys_fictitious_seg, node,
 100     vm_phys_fictitious_cmp);
 101
 102 static struct rwlock vm_phys_fictitious_reg_lock;
 103 MALLOC_DEFINE(M_FICT_PAGES, "vm_fictitious", "Fictitious VM pages");
 104
 105 static struct vm_freelist
 106     vm_phys_free_queues[MAXMEMDOM][VM_NFREELIST][VM_NFREEPOOL][VM_NFREEORDER];
 107
 108 static int vm_nfreelists;
 109
 110 /*
 111  * Provides the mapping from VM_FREELIST_* to free list indices (flind).
 112  */
 113 static int vm_freelist_to_flind[VM_NFREELIST];
 114
 115 CTASSERT(VM_FREELIST_DEFAULT == 0);
 116
 117 #ifdef VM_FREELIST_ISADMA
 118 #define VM_ISADMA_BOUNDARY      16777216
 119 #endif
 120 #ifdef VM_FREELIST_DMA32
 121 #define VM_DMA32_BOUNDARY       ((vm_paddr_t)1 << 32)
 122 #endif
 123
 124 /*
 125  * Enforce the assumptions made by vm_phys_add_seg() and vm_phys_init() about
 126  * the ordering of the free list boundaries.
 127  */
 128 #if defined(VM_ISADMA_BOUNDARY) && defined(VM_LOWMEM_BOUNDARY)
 129 CTASSERT(VM_ISADMA_BOUNDARY < VM_LOWMEM_BOUNDARY);
 130 #endif
 131 #if defined(VM_LOWMEM_BOUNDARY) && defined(VM_DMA32_BOUNDARY)
 132 CTASSERT(VM_LOWMEM_BOUNDARY < VM_DMA32_BOUNDARY);
 133 #endif
 134
 135 static int cnt_prezero;
 136 SYSCTL_INT(_vm_stats_misc, OID_AUTO, cnt_prezero, CTLFLAG_RD,
 137     &cnt_prezero, 0, "The number of physical pages prezeroed at idle time");
 138
 139 static int sysctl_vm_phys_free(SYSCTL_HANDLER_ARGS);
 140 SYSCTL_OID(_vm, OID_AUTO, phys_free, CTLTYPE_STRING | CTLFLAG_RD,
 141     NULL, 0, sysctl_vm_phys_free, "A", "Phys Free Info");
 142
 143 static int sysctl_vm_phys_segs(SYSCTL_HANDLER_ARGS);
 144 SYSCTL_OID(_vm, OID_AUTO, phys_segs, CTLTYPE_STRING | CTLFLAG_RD,
 145     NULL, 0, sysctl_vm_phys_segs, "A", "Phys Seg Info");
 146
 147 #ifdef VM_NUMA_ALLOC
 148 static int sysctl_vm_phys_locality(SYSCTL_HANDLER_ARGS);
 149 SYSCTL_OID(_vm, OID_AUTO, phys_locality, CTLTYPE_STRING | CTLFLAG_RD,
 150     NULL, 0, sysctl_vm_phys_locality, "A", "Phys Locality Info");
 151 #endif
 152
 153 SYSCTL_INT(_vm, OID_AUTO, ndomains, CTLFLAG_RD,
 154     &vm_ndomains, 0, "Number of physical memory domains available.");
 155
 156 /*
 157  * Default to first-touch + round-robin.
 158  */
 159 static struct mtx vm_default_policy_mtx;
 160 MTX_SYSINIT(vm_default_policy, &vm_default_policy_mtx, "default policy mutex",
 161     MTX_DEF);
 162 #ifdef VM_NUMA_ALLOC
 163 static struct vm_domain_policy vm_default_policy =
 164     VM_DOMAIN_POLICY_STATIC_INITIALISER(VM_POLICY_FIRST_TOUCH_ROUND_ROBIN, 0);
 165 #else
 166 /* Use round-robin so the domain policy code will only try once per allocation */
 167 static struct vm_domain_policy vm_default_policy =
 168     VM_DOMAIN_POLICY_STATIC_INITIALISER(VM_POLICY_ROUND_ROBIN, 0);
 169 #endif
 170
 171 static vm_page_t vm_phys_alloc_domain_pages(int domain, int flind, int pool,
 172     int order);
 173 static vm_page_t vm_phys_alloc_seg_contig(struct vm_phys_seg *seg,
 174     u_long npages, vm_paddr_t low, vm_paddr_t high, u_long alignment,
 175     vm_paddr_t boundary);
 176 static void _vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int domain);
 177 static void vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end);
 178 static int vm_phys_paddr_to_segind(vm_paddr_t pa);
 179 static void vm_phys_split_pages(vm_page_t m, int oind, struct vm_freelist *fl,
 180     int order);
 181
 182 static int
 183 sysctl_vm_default_policy(SYSCTL_HANDLER_ARGS)
 184 {
 185         char policy_name[32];
 186         int error;
 187
 188         mtx_lock(&vm_default_policy_mtx);
 189
 190         /* Map policy to output string */
 191         switch (vm_default_policy.p.policy) {
 192         case VM_POLICY_FIRST_TOUCH:
 193                 strcpy(policy_name, "first-touch");
 194                 break;
 195         case VM_POLICY_FIRST_TOUCH_ROUND_ROBIN:
 196                 strcpy(policy_name, "first-touch-rr");
 197                 break;
 198         case VM_POLICY_ROUND_ROBIN:
 199         default:
 200                 strcpy(policy_name, "rr");
 201                 break;
 202         }
 203         mtx_unlock(&vm_default_policy_mtx);
 204
 205         error = sysctl_handle_string(oidp, &policy_name[0],
 206             sizeof(policy_name), req);
 207         if (error != 0 || req->newptr == NULL)
 208                 return (error);
 209
 210         mtx_lock(&vm_default_policy_mtx);
 211         /* Set: match on the subset of policies that make sense as a default */
 212         if (strcmp("first-touch-rr", policy_name) == 0) {
 213                 vm_domain_policy_set(&vm_default_policy,
 214                     VM_POLICY_FIRST_TOUCH_ROUND_ROBIN, 0);
 215         } else if (strcmp("first-touch", policy_name) == 0) {
 216                 vm_domain_policy_set(&vm_default_policy,
 217                     VM_POLICY_FIRST_TOUCH, 0);
 218         } else if (strcmp("rr", policy_name) == 0) {
 219                 vm_domain_policy_set(&vm_default_policy,
 220                     VM_POLICY_ROUND_ROBIN, 0);
 221         } else {
 222                 error = EINVAL;
 223                 goto finish;
 224         }
 225
 226         error = 0;
 227 finish:
 228         mtx_unlock(&vm_default_policy_mtx);
 229         return (error);
 230 }
 231
 232 SYSCTL_PROC(_vm, OID_AUTO, default_policy, CTLTYPE_STRING | CTLFLAG_RW,
 233     0, 0, sysctl_vm_default_policy, "A",
 234     "Default policy (rr, first-touch, first-touch-rr");
 235
 236 /*
 237  * Red-black tree helpers for vm fictitious range management.
 238  */
 239 static inline int
 240 vm_phys_fictitious_in_range(struct vm_phys_fictitious_seg *p,
 241     struct vm_phys_fictitious_seg *range)
 242 {
 243
 244         KASSERT(range->start != 0 && range->end != 0,
 245             ("Invalid range passed on search for vm_fictitious page"));
 246         if (p->start >= range->end)
 247                 return (1);
 248         if (p->start < range->start)
 249                 return (-1);
 250
 251         return (0);
 252 }
 253
 254 static int
 255 vm_phys_fictitious_cmp(struct vm_phys_fictitious_seg *p1,
 256     struct vm_phys_fictitious_seg *p2)
 257 {
 258
 259         /* Check if this is a search for a page */
 260         if (p1->end == 0)
 261                 return (vm_phys_fictitious_in_range(p1, p2));
 262
 263         KASSERT(p2->end != 0,
 264     ("Invalid range passed as second parameter to vm fictitious comparison"));
 265
 266         /* Searching to add a new range */
 267         if (p1->end <= p2->start)
 268                 return (-1);
 269         if (p1->start >= p2->end)
 270                 return (1);
 271
 272         panic("Trying to add overlapping vm fictitious ranges:\n"
 273             "[%#jx:%#jx] and [%#jx:%#jx]", (uintmax_t)p1->start,
 274             (uintmax_t)p1->end, (uintmax_t)p2->start, (uintmax_t)p2->end);
 275 }
 276
 277 static __inline int
 278 vm_rr_selectdomain(void)
 279 {
 280 #ifdef VM_NUMA_ALLOC
 281         struct thread *td;
 282
 283         td = curthread;
 284
 285         td->td_dom_rr_idx++;
 286         td->td_dom_rr_idx %= vm_ndomains;
 287         return (td->td_dom_rr_idx);
 288 #else
 289         return (0);
 290 #endif
 291 }
 292
 293 /*
 294  * Initialise a VM domain iterator.
 295  *
 296  * Check the thread policy, then the proc policy,
 297  * then default to the system policy.
 298  *
 299  * Later on the various layers will have this logic
 300  * plumbed into them and the phys code will be explicitly
 301  * handed a VM domain policy to use.
 302  */
 303 static void
 304 vm_policy_iterator_init(struct vm_domain_iterator *vi)
 305 {
 306 #ifdef VM_NUMA_ALLOC
 307         struct vm_domain_policy lcl;
 308 #endif
 309
 310         vm_domain_iterator_init(vi);
 311
 312 #ifdef VM_NUMA_ALLOC
 313         /* Copy out the thread policy */
 314         vm_domain_policy_localcopy(&lcl, &curthread->td_vm_dom_policy);
 315         if (lcl.p.policy != VM_POLICY_NONE) {
 316                 /* Thread policy is present; use it */
 317                 vm_domain_iterator_set_policy(vi, &lcl);
 318                 return;
 319         }
 320
 321         vm_domain_policy_localcopy(&lcl,
 322             &curthread->td_proc->p_vm_dom_policy);
 323         if (lcl.p.policy != VM_POLICY_NONE) {
 324                 /* Process policy is present; use it */
 325                 vm_domain_iterator_set_policy(vi, &lcl);
 326                 return;
 327         }
 328 #endif
 329         /* Use system default policy */
 330         vm_domain_iterator_set_policy(vi, &vm_default_policy);
 331 }
 332
 333 static void
 334 vm_policy_iterator_finish(struct vm_domain_iterator *vi)
 335 {
 336
 337         vm_domain_iterator_cleanup(vi);
 338 }
 339
 340 boolean_t
 341 vm_phys_domain_intersects(long mask, vm_paddr_t low, vm_paddr_t high)
 342 {
 343         struct vm_phys_seg *s;
 344         int idx;
 345
 346         while ((idx = ffsl(mask)) != 0) {
 347                 idx--;  /* ffsl counts from 1 */
 348                 mask &= ~(1UL << idx);
 349                 s = &vm_phys_segs[idx];
 350                 if (low < s->end && high > s->start)
 351                         return (TRUE);
 352         }
 353         return (FALSE);
 354 }
 355
 356 /*
 357  * Outputs the state of the physical memory allocator, specifically,
 358  * the amount of physical memory in each free list.
 359  */
 360 static int
 361 sysctl_vm_phys_free(SYSCTL_HANDLER_ARGS)
 362 {
 363         struct sbuf sbuf;
 364         struct vm_freelist *fl;
 365         int dom, error, flind, oind, pind;
 366
 367         error = sysctl_wire_old_buffer(req, 0);
 368         if (error != 0)
 369                 return (error);
 370         sbuf_new_for_sysctl(&sbuf, NULL, 128 * vm_ndomains, req);
 371         for (dom = 0; dom < vm_ndomains; dom++) {
 372                 sbuf_printf(&sbuf,"\nDOMAIN %d:\n", dom);
 373                 for (flind = 0; flind < vm_nfreelists; flind++) {
 374                         sbuf_printf(&sbuf, "\nFREE LIST %d:\n"
 375                             "\n  ORDER (SIZE)  |  NUMBER"
 376                             "\n              ", flind);
 377                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
 378                                 sbuf_printf(&sbuf, "  |  POOL %d", pind);
 379                         sbuf_printf(&sbuf, "\n--            ");
 380                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
 381                                 sbuf_printf(&sbuf, "-- --      ");
 382                         sbuf_printf(&sbuf, "--\n");
 383                         for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
 384                                 sbuf_printf(&sbuf, "  %2d (%6dK)", oind,
 385                                     1 << (PAGE_SHIFT - 10 + oind));
 386                                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 387                                 fl = vm_phys_free_queues[dom][flind][pind];
 388                                         sbuf_printf(&sbuf, "  |  %6d",
 389                                             fl[oind].lcnt);
 390                                 }
 391                                 sbuf_printf(&sbuf, "\n");
 392                         }
 393                 }
 394         }
 395         error = sbuf_finish(&sbuf);
 396         sbuf_delete(&sbuf);
 397         return (error);
 398 }
 399
 400 /*
 401  * Outputs the set of physical memory segments.
 402  */
 403 static int
 404 sysctl_vm_phys_segs(SYSCTL_HANDLER_ARGS)
 405 {
 406         struct sbuf sbuf;
 407         struct vm_phys_seg *seg;
 408         int error, segind;
 409
 410         error = sysctl_wire_old_buffer(req, 0);
 411         if (error != 0)
 412                 return (error);
 413         sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
 414         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 415                 sbuf_printf(&sbuf, "\nSEGMENT %d:\n\n", segind);
 416                 seg = &vm_phys_segs[segind];
 417                 sbuf_printf(&sbuf, "start:     %#jx\n",
 418                     (uintmax_t)seg->start);
 419                 sbuf_printf(&sbuf, "end:       %#jx\n",
 420                     (uintmax_t)seg->end);
 421                 sbuf_printf(&sbuf, "domain:    %d\n", seg->domain);
 422                 sbuf_printf(&sbuf, "free list: %p\n", seg->free_queues);
 423         }
 424         error = sbuf_finish(&sbuf);
 425         sbuf_delete(&sbuf);
 426         return (error);
 427 }
 428
 429 /*
 430  * Return affinity, or -1 if there's no affinity information.
 431  */
 432 int
 433 vm_phys_mem_affinity(int f, int t)
 434 {
 435
 436 #ifdef VM_NUMA_ALLOC
 437         if (mem_locality == NULL)
 438                 return (-1);
 439         if (f >= vm_ndomains || t >= vm_ndomains)
 440                 return (-1);
 441         return (mem_locality[f * vm_ndomains + t]);
 442 #else
 443         return (-1);
 444 #endif
 445 }
 446
 447 #ifdef VM_NUMA_ALLOC
 448 /*
 449  * Outputs the VM locality table.
 450  */
 451 static int
 452 sysctl_vm_phys_locality(SYSCTL_HANDLER_ARGS)
 453 {
 454         struct sbuf sbuf;
 455         int error, i, j;
 456
 457         error = sysctl_wire_old_buffer(req, 0);
 458         if (error != 0)
 459                 return (error);
 460         sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
 461
 462         sbuf_printf(&sbuf, "\n");
 463
 464         for (i = 0; i < vm_ndomains; i++) {
 465                 sbuf_printf(&sbuf, "%d: ", i);
 466                 for (j = 0; j < vm_ndomains; j++) {
 467                         sbuf_printf(&sbuf, "%d ", vm_phys_mem_affinity(i, j));
 468                 }
 469                 sbuf_printf(&sbuf, "\n");
 470         }
 471         error = sbuf_finish(&sbuf);
 472         sbuf_delete(&sbuf);
 473         return (error);
 474 }
 475 #endif
 476
 477 static void
 478 vm_freelist_add(struct vm_freelist *fl, vm_page_t m, int order, int tail)
 479 {
 480
 481         m->order = order;
 482         if (tail)
 483                 TAILQ_INSERT_TAIL(&fl[order].pl, m, plinks.q);
 484         else
 485                 TAILQ_INSERT_HEAD(&fl[order].pl, m, plinks.q);
 486         fl[order].lcnt++;
 487 }
 488
 489 static void
 490 vm_freelist_rem(struct vm_freelist *fl, vm_page_t m, int order)
 491 {
 492
 493         TAILQ_REMOVE(&fl[order].pl, m, plinks.q);
 494         fl[order].lcnt--;
 495         m->order = VM_NFREEORDER;
 496 }
 497
 498 /*
 499  * Create a physical memory segment.
 500  */
 501 static void
 502 _vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int domain)
 503 {
 504         struct vm_phys_seg *seg;
 505
 506         KASSERT(vm_phys_nsegs < VM_PHYSSEG_MAX,
 507             ("vm_phys_create_seg: increase VM_PHYSSEG_MAX"));
 508         KASSERT(domain < vm_ndomains,
 509             ("vm_phys_create_seg: invalid domain provided"));
 510         seg = &vm_phys_segs[vm_phys_nsegs++];
 511         while (seg > vm_phys_segs && (seg - 1)->start >= end) {
 512                 *seg = *(seg - 1);
 513                 seg--;
 514         }
 515         seg->start = start;
 516         seg->end = end;
 517         seg->domain = domain;
 518 }
 519
 520 static void
 521 vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end)
 522 {
 523 #ifdef VM_NUMA_ALLOC
 524         int i;
 525
 526         if (mem_affinity == NULL) {
 527                 _vm_phys_create_seg(start, end, 0);
 528                 return;
 529         }
 530
 531         for (i = 0;; i++) {
 532                 if (mem_affinity[i].end == 0)
 533                         panic("Reached end of affinity info");
 534                 if (mem_affinity[i].end <= start)
 535                         continue;
 536                 if (mem_affinity[i].start > start)
 537                         panic("No affinity info for start %jx",
 538                             (uintmax_t)start);
 539                 if (mem_affinity[i].end >= end) {
 540                         _vm_phys_create_seg(start, end,
 541                             mem_affinity[i].domain);
 542                         break;
 543                 }
 544                 _vm_phys_create_seg(start, mem_affinity[i].end,
 545                     mem_affinity[i].domain);
 546                 start = mem_affinity[i].end;
 547         }
 548 #else
 549         _vm_phys_create_seg(start, end, 0);
 550 #endif
 551 }
 552
 553 /*
 554  * Add a physical memory segment.
 555  */
 556 void
 557 vm_phys_add_seg(vm_paddr_t start, vm_paddr_t end)
 558 {
 559         vm_paddr_t paddr;
 560
 561         KASSERT((start & PAGE_MASK) == 0,
 562             ("vm_phys_define_seg: start is not page aligned"));
 563         KASSERT((end & PAGE_MASK) == 0,
 564             ("vm_phys_define_seg: end is not page aligned"));
 565
 566         /*
 567          * Split the physical memory segment if it spans two or more free
 568          * list boundaries.
 569          */
 570         paddr = start;
 571 #ifdef  VM_FREELIST_ISADMA
 572         if (paddr < VM_ISADMA_BOUNDARY && end > VM_ISADMA_BOUNDARY) {
 573                 vm_phys_create_seg(paddr, VM_ISADMA_BOUNDARY);
 574                 paddr = VM_ISADMA_BOUNDARY;
 575         }
 576 #endif
 577 #ifdef  VM_FREELIST_LOWMEM
 578         if (paddr < VM_LOWMEM_BOUNDARY && end > VM_LOWMEM_BOUNDARY) {
 579                 vm_phys_create_seg(paddr, VM_LOWMEM_BOUNDARY);
 580                 paddr = VM_LOWMEM_BOUNDARY;
 581         }
 582 #endif
 583 #ifdef  VM_FREELIST_DMA32
 584         if (paddr < VM_DMA32_BOUNDARY && end > VM_DMA32_BOUNDARY) {
 585                 vm_phys_create_seg(paddr, VM_DMA32_BOUNDARY);
 586                 paddr = VM_DMA32_BOUNDARY;
 587         }
 588 #endif
 589         vm_phys_create_seg(paddr, end);
 590 }
 591
 592 /*
 593  * Initialize the physical memory allocator.
 594  *
 595  * Requires that vm_page_array is initialized!
 596  */
 597 void
 598 vm_phys_init(void)
 599 {
 600         struct vm_freelist *fl;
 601         struct vm_phys_seg *seg;
 602         u_long npages;
 603         int dom, flind, freelist, oind, pind, segind;
 604
 605         /*
 606          * Compute the number of free lists, and generate the mapping from the
 607          * manifest constants VM_FREELIST_* to the free list indices.
 608          *
 609          * Initially, the entries of vm_freelist_to_flind[] are set to either
 610          * 0 or 1 to indicate which free lists should be created.
 611          */
 612         npages = 0;
 613         for (segind = vm_phys_nsegs - 1; segind >= 0; segind--) {
 614                 seg = &vm_phys_segs[segind];
 615 #ifdef  VM_FREELIST_ISADMA
 616                 if (seg->end <= VM_ISADMA_BOUNDARY)
 617                         vm_freelist_to_flind[VM_FREELIST_ISADMA] = 1;
 618                 else
 619 #endif
 620 #ifdef  VM_FREELIST_LOWMEM
 621                 if (seg->end <= VM_LOWMEM_BOUNDARY)
 622                         vm_freelist_to_flind[VM_FREELIST_LOWMEM] = 1;
 623                 else
 624 #endif
 625 #ifdef  VM_FREELIST_DMA32
 626                 if (
 627 #ifdef  VM_DMA32_NPAGES_THRESHOLD
 628                     /*
 629                      * Create the DMA32 free list only if the amount of
 630                      * physical memory above physical address 4G exceeds the
 631                      * given threshold.
 632                      */
 633                     npages > VM_DMA32_NPAGES_THRESHOLD &&
 634 #endif
 635                     seg->end <= VM_DMA32_BOUNDARY)
 636                         vm_freelist_to_flind[VM_FREELIST_DMA32] = 1;
 637                 else
 638 #endif
 639                 {
 640                         npages += atop(seg->end - seg->start);
 641                         vm_freelist_to_flind[VM_FREELIST_DEFAULT] = 1;
 642                 }
 643         }
 644         /* Change each entry into a running total of the free lists. */
 645         for (freelist = 1; freelist < VM_NFREELIST; freelist++) {
 646                 vm_freelist_to_flind[freelist] +=
 647                     vm_freelist_to_flind[freelist - 1];
 648         }
 649         vm_nfreelists = vm_freelist_to_flind[VM_NFREELIST - 1];
 650         KASSERT(vm_nfreelists > 0, ("vm_phys_init: no free lists"));
 651         /* Change each entry into a free list index. */
 652         for (freelist = 0; freelist < VM_NFREELIST; freelist++)
 653                 vm_freelist_to_flind[freelist]--;
 654
 655         /*
 656          * Initialize the first_page and free_queues fields of each physical
 657          * memory segment.
 658          */
 659 #ifdef VM_PHYSSEG_SPARSE
 660         npages = 0;
 661 #endif
 662         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 663                 seg = &vm_phys_segs[segind];
 664 #ifdef VM_PHYSSEG_SPARSE
 665                 seg->first_page = &vm_page_array[npages];
 666                 npages += atop(seg->end - seg->start);
 667 #else
 668                 seg->first_page = PHYS_TO_VM_PAGE(seg->start);
 669 #endif
 670 #ifdef  VM_FREELIST_ISADMA
 671                 if (seg->end <= VM_ISADMA_BOUNDARY) {
 672                         flind = vm_freelist_to_flind[VM_FREELIST_ISADMA];
 673                         KASSERT(flind >= 0,
 674                             ("vm_phys_init: ISADMA flind < 0"));
 675                 } else
 676 #endif
 677 #ifdef  VM_FREELIST_LOWMEM
 678                 if (seg->end <= VM_LOWMEM_BOUNDARY) {
 679                         flind = vm_freelist_to_flind[VM_FREELIST_LOWMEM];
 680                         KASSERT(flind >= 0,
 681                             ("vm_phys_init: LOWMEM flind < 0"));
 682                 } else
 683 #endif
 684 #ifdef  VM_FREELIST_DMA32
 685                 if (seg->end <= VM_DMA32_BOUNDARY) {
 686                         flind = vm_freelist_to_flind[VM_FREELIST_DMA32];
 687                         KASSERT(flind >= 0,
 688                             ("vm_phys_init: DMA32 flind < 0"));
 689                 } else
 690 #endif
 691                 {
 692                         flind = vm_freelist_to_flind[VM_FREELIST_DEFAULT];
 693                         KASSERT(flind >= 0,
 694                             ("vm_phys_init: DEFAULT flind < 0"));
 695                 }
 696                 seg->free_queues = &vm_phys_free_queues[seg->domain][flind];
 697         }
 698
 699         /*
 700          * Initialize the free queues.
 701          */
 702         for (dom = 0; dom < vm_ndomains; dom++) {
 703                 for (flind = 0; flind < vm_nfreelists; flind++) {
 704                         for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 705                                 fl = vm_phys_free_queues[dom][flind][pind];
 706                                 for (oind = 0; oind < VM_NFREEORDER; oind++)
 707                                         TAILQ_INIT(&fl[oind].pl);
 708                         }
 709                 }
 710         }
 711
 712         rw_init(&vm_phys_fictitious_reg_lock, "vmfctr");
 713 }
 714
 715 /*
 716  * Split a contiguous, power of two-sized set of physical pages.
 717  */
 718 static __inline void
 719 vm_phys_split_pages(vm_page_t m, int oind, struct vm_freelist *fl, int order)
 720 {
 721         vm_page_t m_buddy;
 722
 723         while (oind > order) {
 724                 oind--;
 725                 m_buddy = &m[1 << oind];
 726                 KASSERT(m_buddy->order == VM_NFREEORDER,
 727                     ("vm_phys_split_pages: page %p has unexpected order %d",
 728                     m_buddy, m_buddy->order));
 729                 vm_freelist_add(fl, m_buddy, oind, 0);
 730         }
 731 }
 732
 733 /*
 734  * Initialize a physical page and add it to the free lists.
 735  */
 736 void
 737 vm_phys_add_page(vm_paddr_t pa)
 738 {
 739         vm_page_t m;
 740         struct vm_domain *vmd;
 741
 742         vm_cnt.v_page_count++;
 743         m = vm_phys_paddr_to_vm_page(pa);
 744         m->phys_addr = pa;
 745         m->queue = PQ_NONE;
 746         m->segind = vm_phys_paddr_to_segind(pa);
 747         vmd = vm_phys_domain(m);
 748         vmd->vmd_page_count++;
 749         vmd->vmd_segs |= 1UL << m->segind;
 750         KASSERT(m->order == VM_NFREEORDER,
 751             ("vm_phys_add_page: page %p has unexpected order %d",
 752             m, m->order));
 753         m->pool = VM_FREEPOOL_DEFAULT;
 754         pmap_page_init(m);
 755         mtx_lock(&vm_page_queue_free_mtx);
 756         vm_phys_freecnt_adj(m, 1);
 757         vm_phys_free_pages(m, 0);
 758         mtx_unlock(&vm_page_queue_free_mtx);
 759 }
 760
 761 /*
 762  * Allocate a contiguous, power of two-sized set of physical pages
 763  * from the free lists.
 764  *
 765  * The free page queues must be locked.
 766  */
 767 vm_page_t
 768 vm_phys_alloc_pages(int pool, int order)
 769 {
 770         vm_page_t m;
 771         int domain, flind;
 772         struct vm_domain_iterator vi;
 773
 774         KASSERT(pool < VM_NFREEPOOL,
 775             ("vm_phys_alloc_pages: pool %d is out of range", pool));
 776         KASSERT(order < VM_NFREEORDER,
 777             ("vm_phys_alloc_pages: order %d is out of range", order));
 778
 779         vm_policy_iterator_init(&vi);
 780
 781         while ((vm_domain_iterator_run(&vi, &domain)) == 0) {
 782                 for (flind = 0; flind < vm_nfreelists; flind++) {
 783                         m = vm_phys_alloc_domain_pages(domain, flind, pool,
 784                             order);
 785                         if (m != NULL)
 786                                 return (m);
 787                 }
 788         }
 789
 790         vm_policy_iterator_finish(&vi);
 791         return (NULL);
 792 }
 793
 794 /*
 795  * Allocate a contiguous, power of two-sized set of physical pages from the
 796  * specified free list.  The free list must be specified using one of the
 797  * manifest constants VM_FREELIST_*.
 798  *
 799  * The free page queues must be locked.
 800  */
 801 vm_page_t
 802 vm_phys_alloc_freelist_pages(int freelist, int pool, int order)
 803 {
 804         vm_page_t m;
 805         struct vm_domain_iterator vi;
 806         int domain;
 807
 808         KASSERT(freelist < VM_NFREELIST,
 809             ("vm_phys_alloc_freelist_pages: freelist %d is out of range",
 810             freelist));
 811         KASSERT(pool < VM_NFREEPOOL,
 812             ("vm_phys_alloc_freelist_pages: pool %d is out of range", pool));
 813         KASSERT(order < VM_NFREEORDER,
 814             ("vm_phys_alloc_freelist_pages: order %d is out of range", order));
 815
 816         vm_policy_iterator_init(&vi);
 817
 818         while ((vm_domain_iterator_run(&vi, &domain)) == 0) {
 819                 m = vm_phys_alloc_domain_pages(domain,
 820                     vm_freelist_to_flind[freelist], pool, order);
 821                 if (m != NULL)
 822                         return (m);
 823         }
 824
 825         vm_policy_iterator_finish(&vi);
 826         return (NULL);
 827 }
 828
 829 static vm_page_t
 830 vm_phys_alloc_domain_pages(int domain, int flind, int pool, int order)
 831 {
 832         struct vm_freelist *fl;
 833         struct vm_freelist *alt;
 834         int oind, pind;
 835         vm_page_t m;
 836
 837         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
 838         fl = &vm_phys_free_queues[domain][flind][pool][0];
 839         for (oind = order; oind < VM_NFREEORDER; oind++) {
 840                 m = TAILQ_FIRST(&fl[oind].pl);
 841                 if (m != NULL) {
 842                         vm_freelist_rem(fl, m, oind);
 843                         vm_phys_split_pages(m, oind, fl, order);
 844                         return (m);
 845                 }
 846         }
 847
 848         /*
 849          * The given pool was empty.  Find the largest
 850          * contiguous, power-of-two-sized set of pages in any
 851          * pool.  Transfer these pages to the given pool, and
 852          * use them to satisfy the allocation.
 853          */
 854         for (oind = VM_NFREEORDER - 1; oind >= order; oind--) {
 855                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 856                         alt = &vm_phys_free_queues[domain][flind][pind][0];
 857                         m = TAILQ_FIRST(&alt[oind].pl);
 858                         if (m != NULL) {
 859                                 vm_freelist_rem(alt, m, oind);
 860                                 vm_phys_set_pool(pool, m, oind);
 861                                 vm_phys_split_pages(m, oind, fl, order);
 862                                 return (m);
 863                         }
 864                 }
 865         }
 866         return (NULL);
 867 }
 868
 869 /*
 870  * Find the vm_page corresponding to the given physical address.
 871  */
 872 vm_page_t
 873 vm_phys_paddr_to_vm_page(vm_paddr_t pa)
 874 {
 875         struct vm_phys_seg *seg;
 876         int segind;
 877
 878         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 879                 seg = &vm_phys_segs[segind];
 880                 if (pa >= seg->start && pa < seg->end)
 881                         return (&seg->first_page[atop(pa - seg->start)]);
 882         }
 883         return (NULL);
 884 }
 885
 886 vm_page_t
 887 vm_phys_fictitious_to_vm_page(vm_paddr_t pa)
 888 {
 889         struct vm_phys_fictitious_seg tmp, *seg;
 890         vm_page_t m;
 891
 892         m = NULL;
 893         tmp.start = pa;
 894         tmp.end = 0;
 895
 896         rw_rlock(&vm_phys_fictitious_reg_lock);
 897         seg = RB_FIND(fict_tree, &vm_phys_fictitious_tree, &tmp);
 898         rw_runlock(&vm_phys_fictitious_reg_lock);
 899         if (seg == NULL)
 900                 return (NULL);
 901
 902         m = &seg->first_page[atop(pa - seg->start)];
 903         KASSERT((m->flags & PG_FICTITIOUS) != 0, ("%p not fictitious", m));
 904
 905         return (m);
 906 }
 907
 908 static inline void
 909 vm_phys_fictitious_init_range(vm_page_t range, vm_paddr_t start,
 910     long page_count, vm_memattr_t memattr)
 911 {
 912         long i;
 913
 914         for (i = 0; i < page_count; i++) {
 915                 vm_page_initfake(&range[i], start + PAGE_SIZE * i, memattr);
 916                 range[i].oflags &= ~VPO_UNMANAGED;
 917                 range[i].busy_lock = VPB_UNBUSIED;
 918         }
 919 }
 920
 921 int
 922 vm_phys_fictitious_reg_range(vm_paddr_t start, vm_paddr_t end,
 923     vm_memattr_t memattr)
 924 {
 925         struct vm_phys_fictitious_seg *seg;
 926         vm_page_t fp;
 927         long page_count;
 928 #ifdef VM_PHYSSEG_DENSE
 929         long pi, pe;
 930         long dpage_count;
 931 #endif
 932
 933         KASSERT(start < end,
 934             ("Start of segment isn't less than end (start: %jx end: %jx)",
 935             (uintmax_t)start, (uintmax_t)end));
 936
 937         page_count = (end - start) / PAGE_SIZE;
 938
 939 #ifdef VM_PHYSSEG_DENSE
 940         pi = atop(start);
 941         pe = atop(end);
 942         if (pi >= first_page && (pi - first_page) < vm_page_array_size) {
 943                 fp = &vm_page_array[pi - first_page];
 944                 if ((pe - first_page) > vm_page_array_size) {
 945                         /*
 946                          * We have a segment that starts inside
 947                          * of vm_page_array, but ends outside of it.
 948                          *
 949                          * Use vm_page_array pages for those that are
 950                          * inside of the vm_page_array range, and
 951                          * allocate the remaining ones.
 952                          */
 953                         dpage_count = vm_page_array_size - (pi - first_page);
 954                         vm_phys_fictitious_init_range(fp, start, dpage_count,
 955                             memattr);
 956                         page_count -= dpage_count;
 957                         start += ptoa(dpage_count);
 958                         goto alloc;
 959                 }
 960                 /*
 961                  * We can allocate the full range from vm_page_array,
 962                  * so there's no need to register the range in the tree.
 963                  */
 964                 vm_phys_fictitious_init_range(fp, start, page_count, memattr);
 965                 return (0);
 966         } else if (pe > first_page && (pe - first_page) < vm_page_array_size) {
 967                 /*
 968                  * We have a segment that ends inside of vm_page_array,
 969                  * but starts outside of it.
 970                  */
 971                 fp = &vm_page_array[0];
 972                 dpage_count = pe - first_page;
 973                 vm_phys_fictitious_init_range(fp, ptoa(first_page), dpage_count,
 974                     memattr);
 975                 end -= ptoa(dpage_count);
 976                 page_count -= dpage_count;
 977                 goto alloc;
 978         } else if (pi < first_page && pe > (first_page + vm_page_array_size)) {
 979                 /*
 980                  * Trying to register a fictitious range that expands before
 981                  * and after vm_page_array.
 982                  */
 983                 return (EINVAL);
 984         } else {
 985 alloc:
 986 #endif
 987                 fp = malloc(page_count * sizeof(struct vm_page), M_FICT_PAGES,
 988                     M_WAITOK | M_ZERO);
 989 #ifdef VM_PHYSSEG_DENSE
 990         }
 991 #endif
 992         vm_phys_fictitious_init_range(fp, start, page_count, memattr);
 993
 994         seg = malloc(sizeof(*seg), M_FICT_PAGES, M_WAITOK | M_ZERO);
 995         seg->start = start;
 996         seg->end = end;
 997         seg->first_page = fp;
 998
 999         rw_wlock(&vm_phys_fictitious_reg_lock);
1000         RB_INSERT(fict_tree, &vm_phys_fictitious_tree, seg);
1001         rw_wunlock(&vm_phys_fictitious_reg_lock);
1002
1003         return (0);
1004 }
1005
1006 void
1007 vm_phys_fictitious_unreg_range(vm_paddr_t start, vm_paddr_t end)
1008 {
1009         struct vm_phys_fictitious_seg *seg, tmp;
1010 #ifdef VM_PHYSSEG_DENSE
1011         long pi, pe;
1012 #endif
1013
1014         KASSERT(start < end,
1015             ("Start of segment isn't less than end (start: %jx end: %jx)",
1016             (uintmax_t)start, (uintmax_t)end));
1017
1018 #ifdef VM_PHYSSEG_DENSE
1019         pi = atop(start);
1020         pe = atop(end);
1021         if (pi >= first_page && (pi - first_page) < vm_page_array_size) {
1022                 if ((pe - first_page) <= vm_page_array_size) {
1023                         /*
1024                          * This segment was allocated using vm_page_array
1025                          * only, there's nothing to do since those pages
1026                          * were never added to the tree.
1027                          */
1028                         return;
1029                 }
1030                 /*
1031                  * We have a segment that starts inside
1032                  * of vm_page_array, but ends outside of it.
1033                  *
1034                  * Calculate how many pages were added to the
1035                  * tree and free them.
1036                  */
1037                 start = ptoa(first_page + vm_page_array_size);
1038         } else if (pe > first_page && (pe - first_page) < vm_page_array_size) {
1039                 /*
1040                  * We have a segment that ends inside of vm_page_array,
1041                  * but starts outside of it.
1042                  */
1043                 end = ptoa(first_page);
1044         } else if (pi < first_page && pe > (first_page + vm_page_array_size)) {
1045                 /* Since it's not possible to register such a range, panic. */
1046                 panic(
1047                     "Unregistering not registered fictitious range [%#jx:%#jx]",
1048                     (uintmax_t)start, (uintmax_t)end);
1049         }
1050 #endif
1051         tmp.start = start;
1052         tmp.end = 0;
1053
1054         rw_wlock(&vm_phys_fictitious_reg_lock);
1055         seg = RB_FIND(fict_tree, &vm_phys_fictitious_tree, &tmp);
1056         if (seg->start != start || seg->end != end) {
1057                 rw_wunlock(&vm_phys_fictitious_reg_lock);
1058                 panic(
1059                     "Unregistering not registered fictitious range [%#jx:%#jx]",
1060                     (uintmax_t)start, (uintmax_t)end);
1061         }
1062         RB_REMOVE(fict_tree, &vm_phys_fictitious_tree, seg);
1063         rw_wunlock(&vm_phys_fictitious_reg_lock);
1064         free(seg->first_page, M_FICT_PAGES);
1065         free(seg, M_FICT_PAGES);
1066 }
1067
1068 /*
1069  * Find the segment containing the given physical address.
1070  */
1071 static int
1072 vm_phys_paddr_to_segind(vm_paddr_t pa)
1073 {
1074         struct vm_phys_seg *seg;
1075         int segind;
1076
1077         for (segind = 0; segind < vm_phys_nsegs; segind++) {
1078                 seg = &vm_phys_segs[segind];
1079                 if (pa >= seg->start && pa < seg->end)
1080                         return (segind);
1081         }
1082         panic("vm_phys_paddr_to_segind: paddr %#jx is not in any segment" ,
1083             (uintmax_t)pa);
1084 }
1085
1086 /*
1087  * Free a contiguous, power of two-sized set of physical pages.
1088  *
1089  * The free page queues must be locked.
1090  */
1091 void
1092 vm_phys_free_pages(vm_page_t m, int order)
1093 {
1094         struct vm_freelist *fl;
1095         struct vm_phys_seg *seg;
1096         vm_paddr_t pa;
1097         vm_page_t m_buddy;
1098
1099         KASSERT(m->order == VM_NFREEORDER,
1100             ("vm_phys_free_pages: page %p has unexpected order %d",
1101             m, m->order));
1102         KASSERT(m->pool < VM_NFREEPOOL,
1103             ("vm_phys_free_pages: page %p has unexpected pool %d",
1104             m, m->pool));
1105         KASSERT(order < VM_NFREEORDER,
1106             ("vm_phys_free_pages: order %d is out of range", order));
1107         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
1108         seg = &vm_phys_segs[m->segind];
1109         if (order < VM_NFREEORDER - 1) {
1110                 pa = VM_PAGE_TO_PHYS(m);
1111                 do {
1112                         pa ^= ((vm_paddr_t)1 << (PAGE_SHIFT + order));
1113                         if (pa < seg->start || pa >= seg->end)
1114                                 break;
1115                         m_buddy = &seg->first_page[atop(pa - seg->start)];
1116                         if (m_buddy->order != order)
1117                                 break;
1118                         fl = (*seg->free_queues)[m_buddy->pool];
1119                         vm_freelist_rem(fl, m_buddy, order);
1120                         if (m_buddy->pool != m->pool)
1121                                 vm_phys_set_pool(m->pool, m_buddy, order);
1122                         order++;
1123                         pa &= ~(((vm_paddr_t)1 << (PAGE_SHIFT + order)) - 1);
1124                         m = &seg->first_page[atop(pa - seg->start)];
1125                 } while (order < VM_NFREEORDER - 1);
1126         }
1127         fl = (*seg->free_queues)[m->pool];
1128         vm_freelist_add(fl, m, order, 1);
1129 }
1130
1131 /*
1132  * Free a contiguous, arbitrarily sized set of physical pages.
1133  *
1134  * The free page queues must be locked.
1135  */
1136 void
1137 vm_phys_free_contig(vm_page_t m, u_long npages)
1138 {
1139         u_int n;
1140         int order;
1141
1142         /*
1143          * Avoid unnecessary coalescing by freeing the pages in the largest
1144          * possible power-of-two-sized subsets.
1145          */
1146         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
1147         for (;; npages -= n) {
1148                 /*
1149                  * Unsigned "min" is used here so that "order" is assigned
1150                  * "VM_NFREEORDER - 1" when "m"'s physical address is zero
1151                  * or the low-order bits of its physical address are zero
1152                  * because the size of a physical address exceeds the size of
1153                  * a long.
1154                  */
1155                 order = min(ffsl(VM_PAGE_TO_PHYS(m) >> PAGE_SHIFT) - 1,
1156                     VM_NFREEORDER - 1);
1157                 n = 1 << order;
1158                 if (npages < n)
1159                         break;
1160                 vm_phys_free_pages(m, order);
1161                 m += n;
1162         }
1163         /* The residual "npages" is less than "1 << (VM_NFREEORDER - 1)". */
1164         for (; npages > 0; npages -= n) {
1165                 order = flsl(npages) - 1;
1166                 n = 1 << order;
1167                 vm_phys_free_pages(m, order);
1168                 m += n;
1169         }
1170 }
1171
1172 /*
1173  * Scan physical memory between the specified addresses "low" and "high" for a
1174  * run of contiguous physical pages that satisfy the specified conditions, and
1175  * return the lowest page in the run.  The specified "alignment" determines
1176  * the alignment of the lowest physical page in the run.  If the specified
1177  * "boundary" is non-zero, then the run of physical pages cannot span a
1178  * physical address that is a multiple of "boundary".
1179  *
1180  * "npages" must be greater than zero.  Both "alignment" and "boundary" must
1181  * be a power of two.
1182  */
1183 vm_page_t
1184 vm_phys_scan_contig(u_long npages, vm_paddr_t low, vm_paddr_t high,
1185     u_long alignment, vm_paddr_t boundary, int options)
1186 {
1187         vm_paddr_t pa_end;
1188         vm_page_t m_end, m_run, m_start;
1189         struct vm_phys_seg *seg;
1190         int segind;
1191
1192         KASSERT(npages > 0, ("npages is 0"));
1193         KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
1194         KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
1195         if (low >= high)
1196                 return (NULL);
1197         for (segind = 0; segind < vm_phys_nsegs; segind++) {
1198                 seg = &vm_phys_segs[segind];
1199                 if (seg->start >= high)
1200                         break;
1201                 if (low >= seg->end)
1202                         continue;
1203                 if (low <= seg->start)
1204                         m_start = seg->first_page;
1205                 else
1206                         m_start = &seg->first_page[atop(low - seg->start)];
1207                 if (high < seg->end)
1208                         pa_end = high;
1209                 else
1210                         pa_end = seg->end;
1211                 if (pa_end - VM_PAGE_TO_PHYS(m_start) < ptoa(npages))
1212                         continue;
1213                 m_end = &seg->first_page[atop(pa_end - seg->start)];
1214                 m_run = vm_page_scan_contig(npages, m_start, m_end,
1215                     alignment, boundary, options);
1216                 if (m_run != NULL)
1217                         return (m_run);
1218         }
1219         return (NULL);
1220 }
1221
1222 /*
1223  * Set the pool for a contiguous, power of two-sized set of physical pages.
1224  */
1225 void
1226 vm_phys_set_pool(int pool, vm_page_t m, int order)
1227 {
1228         vm_page_t m_tmp;
1229
1230         for (m_tmp = m; m_tmp < &m[1 << order]; m_tmp++)
1231                 m_tmp->pool = pool;
1232 }
1233
1234 /*
1235  * Search for the given physical page "m" in the free lists.  If the search
1236  * succeeds, remove "m" from the free lists and return TRUE.  Otherwise, return
1237  * FALSE, indicating that "m" is not in the free lists.
1238  *
1239  * The free page queues must be locked.
1240  */
1241 boolean_t
1242 vm_phys_unfree_page(vm_page_t m)
1243 {
1244         struct vm_freelist *fl;
1245         struct vm_phys_seg *seg;
1246         vm_paddr_t pa, pa_half;
1247         vm_page_t m_set, m_tmp;
1248         int order;
1249
1250         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
1251
1252         /*
1253          * First, find the contiguous, power of two-sized set of free
1254          * physical pages containing the given physical page "m" and
1255          * assign it to "m_set".
1256          */
1257         seg = &vm_phys_segs[m->segind];
1258         for (m_set = m, order = 0; m_set->order == VM_NFREEORDER &&
1259             order < VM_NFREEORDER - 1; ) {
1260                 order++;
1261                 pa = m->phys_addr & (~(vm_paddr_t)0 << (PAGE_SHIFT + order));
1262                 if (pa >= seg->start)
1263                         m_set = &seg->first_page[atop(pa - seg->start)];
1264                 else
1265                         return (FALSE);
1266         }
1267         if (m_set->order < order)
1268                 return (FALSE);
1269         if (m_set->order == VM_NFREEORDER)
1270                 return (FALSE);
1271         KASSERT(m_set->order < VM_NFREEORDER,
1272             ("vm_phys_unfree_page: page %p has unexpected order %d",
1273             m_set, m_set->order));
1274
1275         /*
1276          * Next, remove "m_set" from the free lists.  Finally, extract
1277          * "m" from "m_set" using an iterative algorithm: While "m_set"
1278          * is larger than a page, shrink "m_set" by returning the half
1279          * of "m_set" that does not contain "m" to the free lists.
1280          */
1281         fl = (*seg->free_queues)[m_set->pool];
1282         order = m_set->order;
1283         vm_freelist_rem(fl, m_set, order);
1284         while (order > 0) {
1285                 order--;
1286                 pa_half = m_set->phys_addr ^ (1 << (PAGE_SHIFT + order));
1287                 if (m->phys_addr < pa_half)
1288                         m_tmp = &seg->first_page[atop(pa_half - seg->start)];
1289                 else {
1290                         m_tmp = m_set;
1291                         m_set = &seg->first_page[atop(pa_half - seg->start)];
1292                 }
1293                 vm_freelist_add(fl, m_tmp, order, 0);
1294         }
1295         KASSERT(m_set == m, ("vm_phys_unfree_page: fatal inconsistency"));
1296         return (TRUE);
1297 }
1298
1299 /*
1300  * Try to zero one physical page.  Used by an idle priority thread.
1301  */
1302 boolean_t
1303 vm_phys_zero_pages_idle(void)
1304 {
1305         static struct vm_freelist *fl;
1306         static int flind, oind, pind;
1307         vm_page_t m, m_tmp;
1308         int domain;
1309
1310         domain = vm_rr_selectdomain();
1311         fl = vm_phys_free_queues[domain][0][0];
1312         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
1313         for (;;) {
1314                 TAILQ_FOREACH_REVERSE(m, &fl[oind].pl, pglist, plinks.q) {
1315                         for (m_tmp = m; m_tmp < &m[1 << oind]; m_tmp++) {
1316                                 if ((m_tmp->flags & (PG_CACHED | PG_ZERO)) == 0) {
1317                                         vm_phys_unfree_page(m_tmp);
1318                                         vm_phys_freecnt_adj(m, -1);
1319                                         mtx_unlock(&vm_page_queue_free_mtx);
1320                                         pmap_zero_page_idle(m_tmp);
1321                                         m_tmp->flags |= PG_ZERO;
1322                                         mtx_lock(&vm_page_queue_free_mtx);
1323                                         vm_phys_freecnt_adj(m, 1);
1324                                         vm_phys_free_pages(m_tmp, 0);
1325                                         vm_page_zero_count++;
1326                                         cnt_prezero++;
1327                                         return (TRUE);
1328                                 }
1329                         }
1330                 }
1331                 oind++;
1332                 if (oind == VM_NFREEORDER) {
1333                         oind = 0;
1334                         pind++;
1335                         if (pind == VM_NFREEPOOL) {
1336                                 pind = 0;
1337                                 flind++;
1338                                 if (flind == vm_nfreelists)
1339                                         flind = 0;
1340                         }
1341                         fl = vm_phys_free_queues[domain][flind][pind];
1342                 }
1343         }
1344 }
1345
1346 /*
1347  * Allocate a contiguous set of physical pages of the given size
1348  * "npages" from the free lists.  All of the physical pages must be at
1349  * or above the given physical address "low" and below the given
1350  * physical address "high".  The given value "alignment" determines the
1351  * alignment of the first physical page in the set.  If the given value
1352  * "boundary" is non-zero, then the set of physical pages cannot cross
1353  * any physical address boundary that is a multiple of that value.  Both
1354  * "alignment" and "boundary" must be a power of two.
1355  */
1356 vm_page_t
1357 vm_phys_alloc_contig(u_long npages, vm_paddr_t low, vm_paddr_t high,
1358     u_long alignment, vm_paddr_t boundary)
1359 {
1360         vm_paddr_t pa_end, pa_start;
1361         vm_page_t m_run;
1362         struct vm_domain_iterator vi;
1363         struct vm_phys_seg *seg;
1364         int domain, segind;
1365
1366         KASSERT(npages > 0, ("npages is 0"));
1367         KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
1368         KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
1369         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
1370         if (low >= high)
1371                 return (NULL);
1372         vm_policy_iterator_init(&vi);
1373 restartdom:
1374         if (vm_domain_iterator_run(&vi, &domain) != 0) {
1375                 vm_policy_iterator_finish(&vi);
1376                 return (NULL);
1377         }
1378         m_run = NULL;
1379         for (segind = vm_phys_nsegs - 1; segind >= 0; segind--) {
1380                 seg = &vm_phys_segs[segind];
1381                 if (seg->start >= high || seg->domain != domain)
1382                         continue;
1383                 if (low >= seg->end)
1384                         break;
1385                 if (low <= seg->start)
1386                         pa_start = seg->start;
1387                 else
1388                         pa_start = low;
1389                 if (high < seg->end)
1390                         pa_end = high;
1391                 else
1392                         pa_end = seg->end;
1393                 if (pa_end - pa_start < ptoa(npages))
1394                         continue;
1395                 m_run = vm_phys_alloc_seg_contig(seg, npages, low, high,
1396                     alignment, boundary);
1397                 if (m_run != NULL)
1398                         break;
1399         }
1400         if (m_run == NULL && !vm_domain_iterator_isdone(&vi))
1401                 goto restartdom;
1402         vm_policy_iterator_finish(&vi);
1403         return (m_run);
1404 }
1405
1406 /*
1407  * Allocate a run of contiguous physical pages from the free list for the
1408  * specified segment.
1409  */
1410 static vm_page_t
1411 vm_phys_alloc_seg_contig(struct vm_phys_seg *seg, u_long npages,
1412     vm_paddr_t low, vm_paddr_t high, u_long alignment, vm_paddr_t boundary)
1413 {
1414         struct vm_freelist *fl;
1415         vm_paddr_t pa, pa_end, size;
1416         vm_page_t m, m_ret;
1417         u_long npages_end;
1418         int oind, order, pind;
1419
1420         KASSERT(npages > 0, ("npages is 0"));
1421         KASSERT(powerof2(alignment), ("alignment is not a power of 2"));
1422         KASSERT(powerof2(boundary), ("boundary is not a power of 2"));
1423         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
1424         /* Compute the queue that is the best fit for npages. */
1425         for (order = 0; (1 << order) < npages; order++);
1426         /* Search for a run satisfying the specified conditions. */
1427         size = npages << PAGE_SHIFT;
1428         for (oind = min(order, VM_NFREEORDER - 1); oind < VM_NFREEORDER;
1429             oind++) {
1430                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
1431                         fl = (*seg->free_queues)[pind];
1432                         TAILQ_FOREACH(m_ret, &fl[oind].pl, plinks.q) {
1433                                 /*
1434                                  * Is the size of this allocation request
1435                                  * larger than the largest block size?
1436                                  */
1437                                 if (order >= VM_NFREEORDER) {
1438                                         /*
1439                                          * Determine if a sufficient number of
1440                                          * subsequent blocks to satisfy the
1441                                          * allocation request are free.
1442                                          */
1443                                         pa = VM_PAGE_TO_PHYS(m_ret);
1444                                         pa_end = pa + size;
1445                                         for (;;) {
1446                                                 pa += 1 << (PAGE_SHIFT +
1447                                                     VM_NFREEORDER - 1);
1448                                                 if (pa >= pa_end ||
1449                                                     pa < seg->start ||
1450                                                     pa >= seg->end)
1451                                                         break;
1452                                                 m = &seg->first_page[atop(pa -
1453                                                     seg->start)];
1454                                                 if (m->order != VM_NFREEORDER -
1455                                                     1)
1456                                                         break;
1457                                         }
1458                                         /* If not, go to the next block. */
1459                                         if (pa < pa_end)
1460                                                 continue;
1461                                 }
1462
1463                                 /*
1464                                  * Determine if the blocks are within the
1465                                  * given range, satisfy the given alignment,
1466                                  * and do not cross the given boundary.
1467                                  */
1468                                 pa = VM_PAGE_TO_PHYS(m_ret);
1469                                 pa_end = pa + size;
1470                                 if (pa >= low && pa_end <= high &&
1471                                     (pa & (alignment - 1)) == 0 &&
1472                                     rounddown2(pa ^ (pa_end - 1), boundary) == 0)
1473                                         goto done;
1474                         }
1475                 }
1476         }
1477         return (NULL);
1478 done:
1479         for (m = m_ret; m < &m_ret[npages]; m = &m[1 << oind]) {
1480                 fl = (*seg->free_queues)[m->pool];
1481                 vm_freelist_rem(fl, m, m->order);
1482         }
1483         if (m_ret->pool != VM_FREEPOOL_DEFAULT)
1484                 vm_phys_set_pool(VM_FREEPOOL_DEFAULT, m_ret, oind);
1485         fl = (*seg->free_queues)[m_ret->pool];
1486         vm_phys_split_pages(m_ret, oind, fl, order);
1487         /* Return excess pages to the free lists. */
1488         npages_end = roundup2(npages, 1 << imin(oind, order));
1489         if (npages < npages_end)
1490                 vm_phys_free_contig(&m_ret[npages], npages_end - npages);
1491         return (m_ret);
1492 }
1493
1494 #ifdef DDB
1495 /*
1496  * Show the number of physical pages in each of the free lists.
1497  */
1498 DB_SHOW_COMMAND(freepages, db_show_freepages)
1499 {
1500         struct vm_freelist *fl;
1501         int flind, oind, pind, dom;
1502
1503         for (dom = 0; dom < vm_ndomains; dom++) {
1504                 db_printf("DOMAIN: %d\n", dom);
1505                 for (flind = 0; flind < vm_nfreelists; flind++) {
1506                         db_printf("FREE LIST %d:\n"
1507                             "\n  ORDER (SIZE)  |  NUMBER"
1508                             "\n              ", flind);
1509                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
1510                                 db_printf("  |  POOL %d", pind);
1511                         db_printf("\n--            ");
1512                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
1513                                 db_printf("-- --      ");
1514                         db_printf("--\n");
1515                         for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
1516                                 db_printf("  %2.2d (%6.6dK)", oind,
1517                                     1 << (PAGE_SHIFT - 10 + oind));
1518                                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
1519                                 fl = vm_phys_free_queues[dom][flind][pind];
1520                                         db_printf("  |  %6.6d", fl[oind].lcnt);
1521                                 }
1522                                 db_printf("\n");
1523                         }
1524                         db_printf("\n");
1525                 }
1526                 db_printf("\n");
1527         }
1528 }
1529 #endif