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 #if MAXMEMDOM > 1
  52 #include <sys/proc.h>
  53 #endif
  54 #include <sys/queue.h>
  55 #include <sys/sbuf.h>
  56 #include <sys/sysctl.h>
  57 #include <sys/vmmeter.h>
  58
  59 #include <ddb/ddb.h>
  60
  61 #include <vm/vm.h>
  62 #include <vm/vm_param.h>
  63 #include <vm/vm_kern.h>
  64 #include <vm/vm_object.h>
  65 #include <vm/vm_page.h>
  66 #include <vm/vm_phys.h>
  67
  68 _Static_assert(sizeof(long) * NBBY >= VM_PHYSSEG_MAX,
  69     "Too many physsegs.");
  70
  71 struct mem_affinity *mem_affinity;
  72
  73 int vm_ndomains = 1;
  74
  75 struct vm_phys_seg vm_phys_segs[VM_PHYSSEG_MAX];
  76 int vm_phys_nsegs;
  77
  78 #define VM_PHYS_FICTITIOUS_NSEGS        8
  79 static struct vm_phys_fictitious_seg {
  80         vm_paddr_t      start;
  81         vm_paddr_t      end;
  82         vm_page_t       first_page;
  83 } vm_phys_fictitious_segs[VM_PHYS_FICTITIOUS_NSEGS];
  84 static struct mtx vm_phys_fictitious_reg_mtx;
  85 MALLOC_DEFINE(M_FICT_PAGES, "vm_fictitious", "Fictitious VM pages");
  86
  87 static struct vm_freelist
  88     vm_phys_free_queues[MAXMEMDOM][VM_NFREELIST][VM_NFREEPOOL][VM_NFREEORDER];
  89
  90 static int vm_nfreelists = VM_FREELIST_DEFAULT + 1;
  91
  92 static int cnt_prezero;
  93 SYSCTL_INT(_vm_stats_misc, OID_AUTO, cnt_prezero, CTLFLAG_RD,
  94     &cnt_prezero, 0, "The number of physical pages prezeroed at idle time");
  95
  96 static int sysctl_vm_phys_free(SYSCTL_HANDLER_ARGS);
  97 SYSCTL_OID(_vm, OID_AUTO, phys_free, CTLTYPE_STRING | CTLFLAG_RD,
  98     NULL, 0, sysctl_vm_phys_free, "A", "Phys Free Info");
  99
 100 static int sysctl_vm_phys_segs(SYSCTL_HANDLER_ARGS);
 101 SYSCTL_OID(_vm, OID_AUTO, phys_segs, CTLTYPE_STRING | CTLFLAG_RD,
 102     NULL, 0, sysctl_vm_phys_segs, "A", "Phys Seg Info");
 103
 104 SYSCTL_INT(_vm, OID_AUTO, ndomains, CTLFLAG_RD,
 105     &vm_ndomains, 0, "Number of physical memory domains available.");
 106
 107 static vm_page_t vm_phys_alloc_domain_pages(int domain, int flind, int pool,
 108     int order);
 109 static void _vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int flind,
 110     int domain);
 111 static void vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int flind);
 112 static int vm_phys_paddr_to_segind(vm_paddr_t pa);
 113 static void vm_phys_split_pages(vm_page_t m, int oind, struct vm_freelist *fl,
 114     int order);
 115
 116 static __inline int
 117 vm_rr_selectdomain(void)
 118 {
 119 #if MAXMEMDOM > 1
 120         struct thread *td;
 121
 122         td = curthread;
 123
 124         td->td_dom_rr_idx++;
 125         td->td_dom_rr_idx %= vm_ndomains;
 126         return (td->td_dom_rr_idx);
 127 #else
 128         return (0);
 129 #endif
 130 }
 131
 132 boolean_t
 133 vm_phys_domain_intersects(long mask, vm_paddr_t low, vm_paddr_t high)
 134 {
 135         struct vm_phys_seg *s;
 136         int idx;
 137
 138         while ((idx = ffsl(mask)) != 0) {
 139                 idx--;  /* ffsl counts from 1 */
 140                 mask &= ~(1UL << idx);
 141                 s = &vm_phys_segs[idx];
 142                 if (low < s->end && high > s->start)
 143                         return (TRUE);
 144         }
 145         return (FALSE);
 146 }
 147
 148 /*
 149  * Outputs the state of the physical memory allocator, specifically,
 150  * the amount of physical memory in each free list.
 151  */
 152 static int
 153 sysctl_vm_phys_free(SYSCTL_HANDLER_ARGS)
 154 {
 155         struct sbuf sbuf;
 156         struct vm_freelist *fl;
 157         int dom, error, flind, oind, pind;
 158
 159         error = sysctl_wire_old_buffer(req, 0);
 160         if (error != 0)
 161                 return (error);
 162         sbuf_new_for_sysctl(&sbuf, NULL, 128 * vm_ndomains, req);
 163         for (dom = 0; dom < vm_ndomains; dom++) {
 164                 sbuf_printf(&sbuf,"DOMAIN: %d\n", dom);
 165                 for (flind = 0; flind < vm_nfreelists; flind++) {
 166                         sbuf_printf(&sbuf, "FREE LIST %d:\n"
 167                             "\n  ORDER (SIZE)  |  NUMBER"
 168                             "\n              ", flind);
 169                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
 170                                 sbuf_printf(&sbuf, "  |  POOL %d", pind);
 171                         sbuf_printf(&sbuf, "\n--            ");
 172                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
 173                                 sbuf_printf(&sbuf, "-- --      ");
 174                         sbuf_printf(&sbuf, "--\n");
 175                         for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
 176                                 sbuf_printf(&sbuf, "  %2d (%6dK)", oind,
 177                                     1 << (PAGE_SHIFT - 10 + oind));
 178                                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 179                                 fl = vm_phys_free_queues[dom][flind][pind];
 180                                         sbuf_printf(&sbuf, "  |  %6.6d",
 181                                             fl[oind].lcnt);
 182                                 }
 183                                 sbuf_printf(&sbuf, "\n");
 184                         }
 185                         sbuf_printf(&sbuf, "\n");
 186                 }
 187                 sbuf_printf(&sbuf, "\n");
 188         }
 189         error = sbuf_finish(&sbuf);
 190         sbuf_delete(&sbuf);
 191         return (error);
 192 }
 193
 194 /*
 195  * Outputs the set of physical memory segments.
 196  */
 197 static int
 198 sysctl_vm_phys_segs(SYSCTL_HANDLER_ARGS)
 199 {
 200         struct sbuf sbuf;
 201         struct vm_phys_seg *seg;
 202         int error, segind;
 203
 204         error = sysctl_wire_old_buffer(req, 0);
 205         if (error != 0)
 206                 return (error);
 207         sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
 208         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 209                 sbuf_printf(&sbuf, "\nSEGMENT %d:\n\n", segind);
 210                 seg = &vm_phys_segs[segind];
 211                 sbuf_printf(&sbuf, "start:     %#jx\n",
 212                     (uintmax_t)seg->start);
 213                 sbuf_printf(&sbuf, "end:       %#jx\n",
 214                     (uintmax_t)seg->end);
 215                 sbuf_printf(&sbuf, "domain:    %d\n", seg->domain);
 216                 sbuf_printf(&sbuf, "free list: %p\n", seg->free_queues);
 217         }
 218         error = sbuf_finish(&sbuf);
 219         sbuf_delete(&sbuf);
 220         return (error);
 221 }
 222
 223 static void
 224 vm_freelist_add(struct vm_freelist *fl, vm_page_t m, int order, int tail)
 225 {
 226
 227         m->order = order;
 228         if (tail)
 229                 TAILQ_INSERT_TAIL(&fl[order].pl, m, pageq);
 230         else
 231                 TAILQ_INSERT_HEAD(&fl[order].pl, m, pageq);
 232         fl[order].lcnt++;
 233 }
 234
 235 static void
 236 vm_freelist_rem(struct vm_freelist *fl, vm_page_t m, int order)
 237 {
 238
 239         TAILQ_REMOVE(&fl[order].pl, m, pageq);
 240         fl[order].lcnt--;
 241         m->order = VM_NFREEORDER;
 242 }
 243
 244 /*
 245  * Create a physical memory segment.
 246  */
 247 static void
 248 _vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int flind, int domain)
 249 {
 250         struct vm_phys_seg *seg;
 251 #ifdef VM_PHYSSEG_SPARSE
 252         long pages;
 253         int segind;
 254
 255         pages = 0;
 256         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 257                 seg = &vm_phys_segs[segind];
 258                 pages += atop(seg->end - seg->start);
 259         }
 260 #endif
 261         KASSERT(vm_phys_nsegs < VM_PHYSSEG_MAX,
 262             ("vm_phys_create_seg: increase VM_PHYSSEG_MAX"));
 263         KASSERT(domain < vm_ndomains,
 264             ("vm_phys_create_seg: invalid domain provided"));
 265         seg = &vm_phys_segs[vm_phys_nsegs++];
 266         seg->start = start;
 267         seg->end = end;
 268         seg->domain = domain;
 269 #ifdef VM_PHYSSEG_SPARSE
 270         seg->first_page = &vm_page_array[pages];
 271 #else
 272         seg->first_page = PHYS_TO_VM_PAGE(start);
 273 #endif
 274         seg->free_queues = &vm_phys_free_queues[domain][flind];
 275 }
 276
 277 static void
 278 vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int flind)
 279 {
 280         int i;
 281
 282         if (mem_affinity == NULL) {
 283                 _vm_phys_create_seg(start, end, flind, 0);
 284                 return;
 285         }
 286
 287         for (i = 0;; i++) {
 288                 if (mem_affinity[i].end == 0)
 289                         panic("Reached end of affinity info");
 290                 if (mem_affinity[i].end <= start)
 291                         continue;
 292                 if (mem_affinity[i].start > start)
 293                         panic("No affinity info for start %jx",
 294                             (uintmax_t)start);
 295                 if (mem_affinity[i].end >= end) {
 296                         _vm_phys_create_seg(start, end, flind,
 297                             mem_affinity[i].domain);
 298                         break;
 299                 }
 300                 _vm_phys_create_seg(start, mem_affinity[i].end, flind,
 301                     mem_affinity[i].domain);
 302                 start = mem_affinity[i].end;
 303         }
 304 }
 305
 306 /*
 307  * Initialize the physical memory allocator.
 308  */
 309 void
 310 vm_phys_init(void)
 311 {
 312         struct vm_freelist *fl;
 313         int dom, flind, i, oind, pind;
 314
 315         for (i = 0; phys_avail[i + 1] != 0; i += 2) {
 316 #ifdef  VM_FREELIST_ISADMA
 317                 if (phys_avail[i] < 16777216) {
 318                         if (phys_avail[i + 1] > 16777216) {
 319                                 vm_phys_create_seg(phys_avail[i], 16777216,
 320                                     VM_FREELIST_ISADMA);
 321                                 vm_phys_create_seg(16777216, phys_avail[i + 1],
 322                                     VM_FREELIST_DEFAULT);
 323                         } else {
 324                                 vm_phys_create_seg(phys_avail[i],
 325                                     phys_avail[i + 1], VM_FREELIST_ISADMA);
 326                         }
 327                         if (VM_FREELIST_ISADMA >= vm_nfreelists)
 328                                 vm_nfreelists = VM_FREELIST_ISADMA + 1;
 329                 } else
 330 #endif
 331 #ifdef  VM_FREELIST_HIGHMEM
 332                 if (phys_avail[i + 1] > VM_HIGHMEM_ADDRESS) {
 333                         if (phys_avail[i] < VM_HIGHMEM_ADDRESS) {
 334                                 vm_phys_create_seg(phys_avail[i],
 335                                     VM_HIGHMEM_ADDRESS, VM_FREELIST_DEFAULT);
 336                                 vm_phys_create_seg(VM_HIGHMEM_ADDRESS,
 337                                     phys_avail[i + 1], VM_FREELIST_HIGHMEM);
 338                         } else {
 339                                 vm_phys_create_seg(phys_avail[i],
 340                                     phys_avail[i + 1], VM_FREELIST_HIGHMEM);
 341                         }
 342                         if (VM_FREELIST_HIGHMEM >= vm_nfreelists)
 343                                 vm_nfreelists = VM_FREELIST_HIGHMEM + 1;
 344                 } else
 345 #endif
 346                 vm_phys_create_seg(phys_avail[i], phys_avail[i + 1],
 347                     VM_FREELIST_DEFAULT);
 348         }
 349         for (dom = 0; dom < vm_ndomains; dom++) {
 350                 for (flind = 0; flind < vm_nfreelists; flind++) {
 351                         for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 352                                 fl = vm_phys_free_queues[dom][flind][pind];
 353                                 for (oind = 0; oind < VM_NFREEORDER; oind++)
 354                                         TAILQ_INIT(&fl[oind].pl);
 355                         }
 356                 }
 357         }
 358         mtx_init(&vm_phys_fictitious_reg_mtx, "vmfctr", NULL, MTX_DEF);
 359 }
 360
 361 /*
 362  * Split a contiguous, power of two-sized set of physical pages.
 363  */
 364 static __inline void
 365 vm_phys_split_pages(vm_page_t m, int oind, struct vm_freelist *fl, int order)
 366 {
 367         vm_page_t m_buddy;
 368
 369         while (oind > order) {
 370                 oind--;
 371                 m_buddy = &m[1 << oind];
 372                 KASSERT(m_buddy->order == VM_NFREEORDER,
 373                     ("vm_phys_split_pages: page %p has unexpected order %d",
 374                     m_buddy, m_buddy->order));
 375                 vm_freelist_add(fl, m_buddy, oind, 0);
 376         }
 377 }
 378
 379 /*
 380  * Initialize a physical page and add it to the free lists.
 381  */
 382 void
 383 vm_phys_add_page(vm_paddr_t pa)
 384 {
 385         vm_page_t m;
 386         struct vm_domain *vmd;
 387
 388         cnt.v_page_count++;
 389         m = vm_phys_paddr_to_vm_page(pa);
 390         m->phys_addr = pa;
 391         m->queue = PQ_NONE;
 392         m->segind = vm_phys_paddr_to_segind(pa);
 393         vmd = vm_phys_domain(m);
 394         vmd->vmd_page_count++;
 395         vmd->vmd_segs |= 1UL << m->segind;
 396         m->flags = PG_FREE;
 397         KASSERT(m->order == VM_NFREEORDER,
 398             ("vm_phys_add_page: page %p has unexpected order %d",
 399             m, m->order));
 400         m->pool = VM_FREEPOOL_DEFAULT;
 401         pmap_page_init(m);
 402         mtx_lock(&vm_page_queue_free_mtx);
 403         vm_phys_freecnt_adj(m, 1);
 404         vm_phys_free_pages(m, 0);
 405         mtx_unlock(&vm_page_queue_free_mtx);
 406 }
 407
 408 /*
 409  * Allocate a contiguous, power of two-sized set of physical pages
 410  * from the free lists.
 411  *
 412  * The free page queues must be locked.
 413  */
 414 vm_page_t
 415 vm_phys_alloc_pages(int pool, int order)
 416 {
 417         vm_page_t m;
 418         int dom, domain, flind;
 419
 420         KASSERT(pool < VM_NFREEPOOL,
 421             ("vm_phys_alloc_pages: pool %d is out of range", pool));
 422         KASSERT(order < VM_NFREEORDER,
 423             ("vm_phys_alloc_pages: order %d is out of range", order));
 424
 425         for (dom = 0; dom < vm_ndomains; dom++) {
 426                 domain = vm_rr_selectdomain();
 427                 for (flind = 0; flind < vm_nfreelists; flind++) {
 428                         m = vm_phys_alloc_domain_pages(domain, flind, pool,
 429                             order);
 430                         if (m != NULL)
 431                                 return (m);
 432                 }
 433         }
 434         return (NULL);
 435 }
 436
 437 /*
 438  * Find and dequeue a free page on the given free list, with the
 439  * specified pool and order
 440  */
 441 vm_page_t
 442 vm_phys_alloc_freelist_pages(int flind, int pool, int order)
 443 {
 444         vm_page_t m;
 445         int dom, domain;
 446
 447         KASSERT(flind < VM_NFREELIST,
 448             ("vm_phys_alloc_freelist_pages: freelist %d is out of range", flind));
 449         KASSERT(pool < VM_NFREEPOOL,
 450             ("vm_phys_alloc_freelist_pages: pool %d is out of range", pool));
 451         KASSERT(order < VM_NFREEORDER,
 452             ("vm_phys_alloc_freelist_pages: order %d is out of range", order));
 453
 454         for (dom = 0; dom < vm_ndomains; dom++) {
 455                 domain = vm_rr_selectdomain();
 456                 m = vm_phys_alloc_domain_pages(domain, flind, pool, order);
 457                 if (m != NULL)
 458                         return (m);
 459         }
 460         return (NULL);
 461 }
 462
 463 static vm_page_t
 464 vm_phys_alloc_domain_pages(int domain, int flind, int pool, int order)
 465 {
 466         struct vm_freelist *fl;
 467         struct vm_freelist *alt;
 468         int oind, pind;
 469         vm_page_t m;
 470
 471         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
 472         fl = &vm_phys_free_queues[domain][flind][pool][0];
 473         for (oind = order; oind < VM_NFREEORDER; oind++) {
 474                 m = TAILQ_FIRST(&fl[oind].pl);
 475                 if (m != NULL) {
 476                         vm_freelist_rem(fl, m, oind);
 477                         vm_phys_split_pages(m, oind, fl, order);
 478                         return (m);
 479                 }
 480         }
 481
 482         /*
 483          * The given pool was empty.  Find the largest
 484          * contiguous, power-of-two-sized set of pages in any
 485          * pool.  Transfer these pages to the given pool, and
 486          * use them to satisfy the allocation.
 487          */
 488         for (oind = VM_NFREEORDER - 1; oind >= order; oind--) {
 489                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 490                         alt = &vm_phys_free_queues[domain][flind][pind][0];
 491                         m = TAILQ_FIRST(&alt[oind].pl);
 492                         if (m != NULL) {
 493                                 vm_freelist_rem(alt, m, oind);
 494                                 vm_phys_set_pool(pool, m, oind);
 495                                 vm_phys_split_pages(m, oind, fl, order);
 496                                 return (m);
 497                         }
 498                 }
 499         }
 500         return (NULL);
 501 }
 502
 503 /*
 504  * Find the vm_page corresponding to the given physical address.
 505  */
 506 vm_page_t
 507 vm_phys_paddr_to_vm_page(vm_paddr_t pa)
 508 {
 509         struct vm_phys_seg *seg;
 510         int segind;
 511
 512         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 513                 seg = &vm_phys_segs[segind];
 514                 if (pa >= seg->start && pa < seg->end)
 515                         return (&seg->first_page[atop(pa - seg->start)]);
 516         }
 517         return (NULL);
 518 }
 519
 520 vm_page_t
 521 vm_phys_fictitious_to_vm_page(vm_paddr_t pa)
 522 {
 523         struct vm_phys_fictitious_seg *seg;
 524         vm_page_t m;
 525         int segind;
 526
 527         m = NULL;
 528         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
 529                 seg = &vm_phys_fictitious_segs[segind];
 530                 if (pa >= seg->start && pa < seg->end) {
 531                         m = &seg->first_page[atop(pa - seg->start)];
 532                         KASSERT((m->flags & PG_FICTITIOUS) != 0,
 533                             ("%p not fictitious", m));
 534                         break;
 535                 }
 536         }
 537         return (m);
 538 }
 539
 540 int
 541 vm_phys_fictitious_reg_range(vm_paddr_t start, vm_paddr_t end,
 542     vm_memattr_t memattr)
 543 {
 544         struct vm_phys_fictitious_seg *seg;
 545         vm_page_t fp;
 546         long i, page_count;
 547         int segind;
 548 #ifdef VM_PHYSSEG_DENSE
 549         long pi;
 550         boolean_t malloced;
 551 #endif
 552
 553         page_count = (end - start) / PAGE_SIZE;
 554
 555 #ifdef VM_PHYSSEG_DENSE
 556         pi = atop(start);
 557         if (pi >= first_page && atop(end) < vm_page_array_size) {
 558                 fp = &vm_page_array[pi - first_page];
 559                 malloced = FALSE;
 560         } else
 561 #endif
 562         {
 563                 fp = malloc(page_count * sizeof(struct vm_page), M_FICT_PAGES,
 564                     M_WAITOK | M_ZERO);
 565 #ifdef VM_PHYSSEG_DENSE
 566                 malloced = TRUE;
 567 #endif
 568         }
 569         for (i = 0; i < page_count; i++) {
 570                 vm_page_initfake(&fp[i], start + PAGE_SIZE * i, memattr);
 571                 fp[i].oflags &= ~(VPO_BUSY | VPO_UNMANAGED);
 572         }
 573         mtx_lock(&vm_phys_fictitious_reg_mtx);
 574         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
 575                 seg = &vm_phys_fictitious_segs[segind];
 576                 if (seg->start == 0 && seg->end == 0) {
 577                         seg->start = start;
 578                         seg->end = end;
 579                         seg->first_page = fp;
 580                         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 581                         return (0);
 582                 }
 583         }
 584         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 585 #ifdef VM_PHYSSEG_DENSE
 586         if (malloced)
 587 #endif
 588                 free(fp, M_FICT_PAGES);
 589         return (EBUSY);
 590 }
 591
 592 void
 593 vm_phys_fictitious_unreg_range(vm_paddr_t start, vm_paddr_t end)
 594 {
 595         struct vm_phys_fictitious_seg *seg;
 596         vm_page_t fp;
 597         int segind;
 598 #ifdef VM_PHYSSEG_DENSE
 599         long pi;
 600 #endif
 601
 602 #ifdef VM_PHYSSEG_DENSE
 603         pi = atop(start);
 604 #endif
 605
 606         mtx_lock(&vm_phys_fictitious_reg_mtx);
 607         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
 608                 seg = &vm_phys_fictitious_segs[segind];
 609                 if (seg->start == start && seg->end == end) {
 610                         seg->start = seg->end = 0;
 611                         fp = seg->first_page;
 612                         seg->first_page = NULL;
 613                         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 614 #ifdef VM_PHYSSEG_DENSE
 615                         if (pi < first_page || atop(end) >= vm_page_array_size)
 616 #endif
 617                                 free(fp, M_FICT_PAGES);
 618                         return;
 619                 }
 620         }
 621         mtx_unlock(&vm_phys_fictitious_reg_mtx);
 622         KASSERT(0, ("Unregistering not registered fictitious range"));
 623 }
 624
 625 /*
 626  * Find the segment containing the given physical address.
 627  */
 628 static int
 629 vm_phys_paddr_to_segind(vm_paddr_t pa)
 630 {
 631         struct vm_phys_seg *seg;
 632         int segind;
 633
 634         for (segind = 0; segind < vm_phys_nsegs; segind++) {
 635                 seg = &vm_phys_segs[segind];
 636                 if (pa >= seg->start && pa < seg->end)
 637                         return (segind);
 638         }
 639         panic("vm_phys_paddr_to_segind: paddr %#jx is not in any segment" ,
 640             (uintmax_t)pa);
 641 }
 642
 643 /*
 644  * Free a contiguous, power of two-sized set of physical pages.
 645  *
 646  * The free page queues must be locked.
 647  */
 648 void
 649 vm_phys_free_pages(vm_page_t m, int order)
 650 {
 651         struct vm_freelist *fl;
 652         struct vm_phys_seg *seg;
 653         vm_paddr_t pa;
 654         vm_page_t m_buddy;
 655
 656         KASSERT(m->order == VM_NFREEORDER,
 657             ("vm_phys_free_pages: page %p has unexpected order %d",
 658             m, m->order));
 659         KASSERT(m->pool < VM_NFREEPOOL,
 660             ("vm_phys_free_pages: page %p has unexpected pool %d",
 661             m, m->pool));
 662         KASSERT(order < VM_NFREEORDER,
 663             ("vm_phys_free_pages: order %d is out of range", order));
 664         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
 665         seg = &vm_phys_segs[m->segind];
 666         if (order < VM_NFREEORDER - 1) {
 667                 pa = VM_PAGE_TO_PHYS(m);
 668                 do {
 669                         pa ^= ((vm_paddr_t)1 << (PAGE_SHIFT + order));
 670                         if (pa < seg->start || pa >= seg->end)
 671                                 break;
 672                         m_buddy = &seg->first_page[atop(pa - seg->start)];
 673                         if (m_buddy->order != order)
 674                                 break;
 675                         fl = (*seg->free_queues)[m_buddy->pool];
 676                         vm_freelist_rem(fl, m_buddy, order);
 677                         if (m_buddy->pool != m->pool)
 678                                 vm_phys_set_pool(m->pool, m_buddy, order);
 679                         order++;
 680                         pa &= ~(((vm_paddr_t)1 << (PAGE_SHIFT + order)) - 1);
 681                         m = &seg->first_page[atop(pa - seg->start)];
 682                 } while (order < VM_NFREEORDER - 1);
 683         }
 684         fl = (*seg->free_queues)[m->pool];
 685         vm_freelist_add(fl, m, order, 1);
 686 }
 687
 688 /*
 689  * Free a contiguous, arbitrarily sized set of physical pages.
 690  *
 691  * The free page queues must be locked.
 692  */
 693 void
 694 vm_phys_free_contig(vm_page_t m, u_long npages)
 695 {
 696         u_int n;
 697         int order;
 698
 699         /*
 700          * Avoid unnecessary coalescing by freeing the pages in the largest
 701          * possible power-of-two-sized subsets.
 702          */
 703         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
 704         for (;; npages -= n) {
 705                 /*
 706                  * Unsigned "min" is used here so that "order" is assigned
 707                  * "VM_NFREEORDER - 1" when "m"'s physical address is zero
 708                  * or the low-order bits of its physical address are zero
 709                  * because the size of a physical address exceeds the size of
 710                  * a long.
 711                  */
 712                 order = min(ffsl(VM_PAGE_TO_PHYS(m) >> PAGE_SHIFT) - 1,
 713                     VM_NFREEORDER - 1);
 714                 n = 1 << order;
 715                 if (npages < n)
 716                         break;
 717                 vm_phys_free_pages(m, order);
 718                 m += n;
 719         }
 720         /* The residual "npages" is less than "1 << (VM_NFREEORDER - 1)". */
 721         for (; npages > 0; npages -= n) {
 722                 order = flsl(npages) - 1;
 723                 n = 1 << order;
 724                 vm_phys_free_pages(m, order);
 725                 m += n;
 726         }
 727 }
 728
 729 /*
 730  * Set the pool for a contiguous, power of two-sized set of physical pages.
 731  */
 732 void
 733 vm_phys_set_pool(int pool, vm_page_t m, int order)
 734 {
 735         vm_page_t m_tmp;
 736
 737         for (m_tmp = m; m_tmp < &m[1 << order]; m_tmp++)
 738                 m_tmp->pool = pool;
 739 }
 740
 741 /*
 742  * Search for the given physical page "m" in the free lists.  If the search
 743  * succeeds, remove "m" from the free lists and return TRUE.  Otherwise, return
 744  * FALSE, indicating that "m" is not in the free lists.
 745  *
 746  * The free page queues must be locked.
 747  */
 748 boolean_t
 749 vm_phys_unfree_page(vm_page_t m)
 750 {
 751         struct vm_freelist *fl;
 752         struct vm_phys_seg *seg;
 753         vm_paddr_t pa, pa_half;
 754         vm_page_t m_set, m_tmp;
 755         int order;
 756
 757         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
 758
 759         /*
 760          * First, find the contiguous, power of two-sized set of free
 761          * physical pages containing the given physical page "m" and
 762          * assign it to "m_set".
 763          */
 764         seg = &vm_phys_segs[m->segind];
 765         for (m_set = m, order = 0; m_set->order == VM_NFREEORDER &&
 766             order < VM_NFREEORDER - 1; ) {
 767                 order++;
 768                 pa = m->phys_addr & (~(vm_paddr_t)0 << (PAGE_SHIFT + order));
 769                 if (pa >= seg->start)
 770                         m_set = &seg->first_page[atop(pa - seg->start)];
 771                 else
 772                         return (FALSE);
 773         }
 774         if (m_set->order < order)
 775                 return (FALSE);
 776         if (m_set->order == VM_NFREEORDER)
 777                 return (FALSE);
 778         KASSERT(m_set->order < VM_NFREEORDER,
 779             ("vm_phys_unfree_page: page %p has unexpected order %d",
 780             m_set, m_set->order));
 781
 782         /*
 783          * Next, remove "m_set" from the free lists.  Finally, extract
 784          * "m" from "m_set" using an iterative algorithm: While "m_set"
 785          * is larger than a page, shrink "m_set" by returning the half
 786          * of "m_set" that does not contain "m" to the free lists.
 787          */
 788         fl = (*seg->free_queues)[m_set->pool];
 789         order = m_set->order;
 790         vm_freelist_rem(fl, m_set, order);
 791         while (order > 0) {
 792                 order--;
 793                 pa_half = m_set->phys_addr ^ (1 << (PAGE_SHIFT + order));
 794                 if (m->phys_addr < pa_half)
 795                         m_tmp = &seg->first_page[atop(pa_half - seg->start)];
 796                 else {
 797                         m_tmp = m_set;
 798                         m_set = &seg->first_page[atop(pa_half - seg->start)];
 799                 }
 800                 vm_freelist_add(fl, m_tmp, order, 0);
 801         }
 802         KASSERT(m_set == m, ("vm_phys_unfree_page: fatal inconsistency"));
 803         return (TRUE);
 804 }
 805
 806 /*
 807  * Try to zero one physical page.  Used by an idle priority thread.
 808  */
 809 boolean_t
 810 vm_phys_zero_pages_idle(void)
 811 {
 812         static struct vm_freelist *fl;
 813         static int flind, oind, pind;
 814         vm_page_t m, m_tmp;
 815         int domain;
 816
 817         domain = vm_rr_selectdomain();
 818         fl = vm_phys_free_queues[domain][0][0];
 819         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
 820         for (;;) {
 821                 TAILQ_FOREACH_REVERSE(m, &fl[oind].pl, pglist, pageq) {
 822                         for (m_tmp = m; m_tmp < &m[1 << oind]; m_tmp++) {
 823                                 if ((m_tmp->flags & (PG_CACHED | PG_ZERO)) == 0) {
 824                                         vm_phys_unfree_page(m_tmp);
 825                                         vm_phys_freecnt_adj(m, -1);
 826                                         mtx_unlock(&vm_page_queue_free_mtx);
 827                                         pmap_zero_page_idle(m_tmp);
 828                                         m_tmp->flags |= PG_ZERO;
 829                                         mtx_lock(&vm_page_queue_free_mtx);
 830                                         vm_phys_freecnt_adj(m, 1);
 831                                         vm_phys_free_pages(m_tmp, 0);
 832                                         vm_page_zero_count++;
 833                                         cnt_prezero++;
 834                                         return (TRUE);
 835                                 }
 836                         }
 837                 }
 838                 oind++;
 839                 if (oind == VM_NFREEORDER) {
 840                         oind = 0;
 841                         pind++;
 842                         if (pind == VM_NFREEPOOL) {
 843                                 pind = 0;
 844                                 flind++;
 845                                 if (flind == vm_nfreelists)
 846                                         flind = 0;
 847                         }
 848                         fl = vm_phys_free_queues[domain][flind][pind];
 849                 }
 850         }
 851 }
 852
 853 /*
 854  * Allocate a contiguous set of physical pages of the given size
 855  * "npages" from the free lists.  All of the physical pages must be at
 856  * or above the given physical address "low" and below the given
 857  * physical address "high".  The given value "alignment" determines the
 858  * alignment of the first physical page in the set.  If the given value
 859  * "boundary" is non-zero, then the set of physical pages cannot cross
 860  * any physical address boundary that is a multiple of that value.  Both
 861  * "alignment" and "boundary" must be a power of two.
 862  */
 863 vm_page_t
 864 vm_phys_alloc_contig(u_long npages, vm_paddr_t low, vm_paddr_t high,
 865     u_long alignment, vm_paddr_t boundary)
 866 {
 867         struct vm_freelist *fl;
 868         struct vm_phys_seg *seg;
 869         vm_paddr_t pa, pa_last, size;
 870         vm_page_t m, m_ret;
 871         u_long npages_end;
 872         int dom, domain, flind, oind, order, pind;
 873
 874         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
 875         size = npages << PAGE_SHIFT;
 876         KASSERT(size != 0,
 877             ("vm_phys_alloc_contig: size must not be 0"));
 878         KASSERT((alignment & (alignment - 1)) == 0,
 879             ("vm_phys_alloc_contig: alignment must be a power of 2"));
 880         KASSERT((boundary & (boundary - 1)) == 0,
 881             ("vm_phys_alloc_contig: boundary must be a power of 2"));
 882         /* Compute the queue that is the best fit for npages. */
 883         for (order = 0; (1 << order) < npages; order++);
 884         dom = 0;
 885 restartdom:
 886         domain = vm_rr_selectdomain();
 887         for (flind = 0; flind < vm_nfreelists; flind++) {
 888                 for (oind = min(order, VM_NFREEORDER - 1); oind < VM_NFREEORDER; oind++) {
 889                         for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 890                                 fl = &vm_phys_free_queues[domain][flind][pind][0];
 891                                 TAILQ_FOREACH(m_ret, &fl[oind].pl, pageq) {
 892                                         /*
 893                                          * A free list may contain physical pages
 894                                          * from one or more segments.
 895                                          */
 896                                         seg = &vm_phys_segs[m_ret->segind];
 897                                         if (seg->start > high ||
 898                                             low >= seg->end)
 899                                                 continue;
 900
 901                                         /*
 902                                          * Is the size of this allocation request
 903                                          * larger than the largest block size?
 904                                          */
 905                                         if (order >= VM_NFREEORDER) {
 906                                                 /*
 907                                                  * Determine if a sufficient number
 908                                                  * of subsequent blocks to satisfy
 909                                                  * the allocation request are free.
 910                                                  */
 911                                                 pa = VM_PAGE_TO_PHYS(m_ret);
 912                                                 pa_last = pa + size;
 913                                                 for (;;) {
 914                                                         pa += 1 << (PAGE_SHIFT + VM_NFREEORDER - 1);
 915                                                         if (pa >= pa_last)
 916                                                                 break;
 917                                                         if (pa < seg->start ||
 918                                                             pa >= seg->end)
 919                                                                 break;
 920                                                         m = &seg->first_page[atop(pa - seg->start)];
 921                                                         if (m->order != VM_NFREEORDER - 1)
 922                                                                 break;
 923                                                 }
 924                                                 /* If not, continue to the next block. */
 925                                                 if (pa < pa_last)
 926                                                         continue;
 927                                         }
 928
 929                                         /*
 930                                          * Determine if the blocks are within the given range,
 931                                          * satisfy the given alignment, and do not cross the
 932                                          * given boundary.
 933                                          */
 934                                         pa = VM_PAGE_TO_PHYS(m_ret);
 935                                         if (pa >= low &&
 936                                             pa + size <= high &&
 937                                             (pa & (alignment - 1)) == 0 &&
 938                                             ((pa ^ (pa + size - 1)) & ~(boundary - 1)) == 0)
 939                                                 goto done;
 940                                 }
 941                         }
 942                 }
 943         }
 944         if (++dom < vm_ndomains)
 945                 goto restartdom;
 946         return (NULL);
 947 done:
 948         for (m = m_ret; m < &m_ret[npages]; m = &m[1 << oind]) {
 949                 fl = (*seg->free_queues)[m->pool];
 950                 vm_freelist_rem(fl, m, m->order);
 951         }
 952         if (m_ret->pool != VM_FREEPOOL_DEFAULT)
 953                 vm_phys_set_pool(VM_FREEPOOL_DEFAULT, m_ret, oind);
 954         fl = (*seg->free_queues)[m_ret->pool];
 955         vm_phys_split_pages(m_ret, oind, fl, order);
 956         /* Return excess pages to the free lists. */
 957         npages_end = roundup2(npages, 1 << imin(oind, order));
 958         if (npages < npages_end)
 959                 vm_phys_free_contig(&m_ret[npages], npages_end - npages);
 960         return (m_ret);
 961 }
 962
 963 #ifdef DDB
 964 /*
 965  * Show the number of physical pages in each of the free lists.
 966  */
 967 DB_SHOW_COMMAND(freepages, db_show_freepages)
 968 {
 969         struct vm_freelist *fl;
 970         int flind, oind, pind, dom;
 971
 972         for (dom = 0; dom < vm_ndomains; dom++) {
 973                 db_printf("DOMAIN: %d\n", dom);
 974                 for (flind = 0; flind < vm_nfreelists; flind++) {
 975                         db_printf("FREE LIST %d:\n"
 976                             "\n  ORDER (SIZE)  |  NUMBER"
 977                             "\n              ", flind);
 978                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
 979                                 db_printf("  |  POOL %d", pind);
 980                         db_printf("\n--            ");
 981                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
 982                                 db_printf("-- --      ");
 983                         db_printf("--\n");
 984                         for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
 985                                 db_printf("  %2.2d (%6.6dK)", oind,
 986                                     1 << (PAGE_SHIFT - 10 + oind));
 987                                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 988                                 fl = vm_phys_free_queues[dom][flind][pind];
 989                                         db_printf("  |  %6.6d", fl[oind].lcnt);
 990                                 }
 991                                 db_printf("\n");
 992                         }
 993                         db_printf("\n");
 994                 }
 995                 db_printf("\n");
 996         }
 997 }
 998 #endif