vm_phys.c

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    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: releng/10.4/sys/vm/vm_phys.c 308349 2016-11-05 20:14:23Z markj $");
   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;
   91 
   92 /*
   93  * Provides the mapping from VM_FREELIST_* to free list indices (flind).
   94  */
   95 static int vm_freelist_to_flind[VM_NFREELIST];
   96 
   97 CTASSERT(VM_FREELIST_DEFAULT == 0);
   98 
   99 #ifdef VM_FREELIST_ISADMA
  100 #define VM_ISADMA_BOUNDARY      16777216
  101 #endif
  102 #ifdef VM_FREELIST_DMA32
  103 #define VM_DMA32_BOUNDARY       ((vm_paddr_t)1 << 32)
  104 #endif
  105 
  106 /*
  107  * Enforce the assumptions made by vm_phys_add_seg() and vm_phys_init() about
  108  * the ordering of the free list boundaries.
  109  */
  110 #if defined(VM_ISADMA_BOUNDARY) && defined(VM_LOWMEM_BOUNDARY)
  111 CTASSERT(VM_ISADMA_BOUNDARY < VM_LOWMEM_BOUNDARY);
  112 #endif
  113 #if defined(VM_LOWMEM_BOUNDARY) && defined(VM_DMA32_BOUNDARY)
  114 CTASSERT(VM_LOWMEM_BOUNDARY < VM_DMA32_BOUNDARY);
  115 #endif
  116 
  117 static int cnt_prezero;
  118 SYSCTL_INT(_vm_stats_misc, OID_AUTO, cnt_prezero, CTLFLAG_RD,
  119     &cnt_prezero, 0, "The number of physical pages prezeroed at idle time");
  120 
  121 static int sysctl_vm_phys_free(SYSCTL_HANDLER_ARGS);
  122 SYSCTL_OID(_vm, OID_AUTO, phys_free, CTLTYPE_STRING | CTLFLAG_RD,
  123     NULL, 0, sysctl_vm_phys_free, "A", "Phys Free Info");
  124 
  125 static int sysctl_vm_phys_segs(SYSCTL_HANDLER_ARGS);
  126 SYSCTL_OID(_vm, OID_AUTO, phys_segs, CTLTYPE_STRING | CTLFLAG_RD,
  127     NULL, 0, sysctl_vm_phys_segs, "A", "Phys Seg Info");
  128 
  129 SYSCTL_INT(_vm, OID_AUTO, ndomains, CTLFLAG_RD,
  130     &vm_ndomains, 0, "Number of physical memory domains available.");
  131 
  132 static vm_page_t vm_phys_alloc_domain_pages(int domain, int flind, int pool,
  133     int order);
  134 static void _vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int domain);
  135 static void vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end);
  136 static int vm_phys_paddr_to_segind(vm_paddr_t pa);
  137 static void vm_phys_split_pages(vm_page_t m, int oind, struct vm_freelist *fl,
  138     int order);
  139 
  140 static __inline int
  141 vm_rr_selectdomain(void)
  142 {
  143 #if MAXMEMDOM > 1
  144         struct thread *td;
  145 
  146         td = curthread;
  147 
  148         td->td_dom_rr_idx++;
  149         td->td_dom_rr_idx %= vm_ndomains;
  150         return (td->td_dom_rr_idx);
  151 #else
  152         return (0);
  153 #endif
  154 }
  155 
  156 boolean_t
  157 vm_phys_domain_intersects(long mask, vm_paddr_t low, vm_paddr_t high)
  158 {
  159         struct vm_phys_seg *s;
  160         int idx;
  161 
  162         while ((idx = ffsl(mask)) != 0) {
  163                 idx--;  /* ffsl counts from 1 */
  164                 mask &= ~(1UL << idx);
  165                 s = &vm_phys_segs[idx];
  166                 if (low < s->end && high > s->start)
  167                         return (TRUE);
  168         }
  169         return (FALSE);
  170 }
  171 
  172 /*
  173  * Outputs the state of the physical memory allocator, specifically,
  174  * the amount of physical memory in each free list.
  175  */
  176 static int
  177 sysctl_vm_phys_free(SYSCTL_HANDLER_ARGS)
  178 {
  179         struct sbuf sbuf;
  180         struct vm_freelist *fl;
  181         int dom, error, flind, oind, pind;
  182 
  183         error = sysctl_wire_old_buffer(req, 0);
  184         if (error != 0)
  185                 return (error);
  186         sbuf_new_for_sysctl(&sbuf, NULL, 128 * vm_ndomains, req);
  187         for (dom = 0; dom < vm_ndomains; dom++) {
  188                 sbuf_printf(&sbuf,"\nDOMAIN %d:\n", dom);
  189                 for (flind = 0; flind < vm_nfreelists; flind++) {
  190                         sbuf_printf(&sbuf, "\nFREE LIST %d:\n"
  191                             "\n  ORDER (SIZE)  |  NUMBER"
  192                             "\n              ", flind);
  193                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
  194                                 sbuf_printf(&sbuf, "  |  POOL %d", pind);
  195                         sbuf_printf(&sbuf, "\n--            ");
  196                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
  197                                 sbuf_printf(&sbuf, "-- --      ");
  198                         sbuf_printf(&sbuf, "--\n");
  199                         for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
  200                                 sbuf_printf(&sbuf, "  %2d (%6dK)", oind,
  201                                     1 << (PAGE_SHIFT - 10 + oind));
  202                                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
  203                                 fl = vm_phys_free_queues[dom][flind][pind];
  204                                         sbuf_printf(&sbuf, "  |  %6d",
  205                                             fl[oind].lcnt);
  206                                 }
  207                                 sbuf_printf(&sbuf, "\n");
  208                         }
  209                 }
  210         }
  211         error = sbuf_finish(&sbuf);
  212         sbuf_delete(&sbuf);
  213         return (error);
  214 }
  215 
  216 /*
  217  * Outputs the set of physical memory segments.
  218  */
  219 static int
  220 sysctl_vm_phys_segs(SYSCTL_HANDLER_ARGS)
  221 {
  222         struct sbuf sbuf;
  223         struct vm_phys_seg *seg;
  224         int error, segind;
  225 
  226         error = sysctl_wire_old_buffer(req, 0);
  227         if (error != 0)
  228                 return (error);
  229         sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
  230         for (segind = 0; segind < vm_phys_nsegs; segind++) {
  231                 sbuf_printf(&sbuf, "\nSEGMENT %d:\n\n", segind);
  232                 seg = &vm_phys_segs[segind];
  233                 sbuf_printf(&sbuf, "start:     %#jx\n",
  234                     (uintmax_t)seg->start);
  235                 sbuf_printf(&sbuf, "end:       %#jx\n",
  236                     (uintmax_t)seg->end);
  237                 sbuf_printf(&sbuf, "domain:    %d\n", seg->domain);
  238                 sbuf_printf(&sbuf, "free list: %p\n", seg->free_queues);
  239         }
  240         error = sbuf_finish(&sbuf);
  241         sbuf_delete(&sbuf);
  242         return (error);
  243 }
  244 
  245 static void
  246 vm_freelist_add(struct vm_freelist *fl, vm_page_t m, int order, int tail)
  247 {
  248 
  249         m->order = order;
  250         if (tail)
  251                 TAILQ_INSERT_TAIL(&fl[order].pl, m, plinks.q);
  252         else
  253                 TAILQ_INSERT_HEAD(&fl[order].pl, m, plinks.q);
  254         fl[order].lcnt++;
  255 }
  256 
  257 static void
  258 vm_freelist_rem(struct vm_freelist *fl, vm_page_t m, int order)
  259 {
  260 
  261         TAILQ_REMOVE(&fl[order].pl, m, plinks.q);
  262         fl[order].lcnt--;
  263         m->order = VM_NFREEORDER;
  264 }
  265 
  266 /*
  267  * Create a physical memory segment.
  268  */
  269 static void
  270 _vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end, int domain)
  271 {
  272         struct vm_phys_seg *seg;
  273 
  274         KASSERT(vm_phys_nsegs < VM_PHYSSEG_MAX,
  275             ("vm_phys_create_seg: increase VM_PHYSSEG_MAX"));
  276         KASSERT(domain < vm_ndomains,
  277             ("vm_phys_create_seg: invalid domain provided"));
  278         seg = &vm_phys_segs[vm_phys_nsegs++];
  279         while (seg > vm_phys_segs && (seg - 1)->start >= end) {
  280                 *seg = *(seg - 1);
  281                 seg--;
  282         }
  283         seg->start = start;
  284         seg->end = end;
  285         seg->domain = domain;
  286 }
  287 
  288 static void
  289 vm_phys_create_seg(vm_paddr_t start, vm_paddr_t end)
  290 {
  291         int i;
  292 
  293         if (mem_affinity == NULL) {
  294                 _vm_phys_create_seg(start, end, 0);
  295                 return;
  296         }
  297 
  298         for (i = 0;; i++) {
  299                 if (mem_affinity[i].end == 0)
  300                         panic("Reached end of affinity info");
  301                 if (mem_affinity[i].end <= start)
  302                         continue;
  303                 if (mem_affinity[i].start > start)
  304                         panic("No affinity info for start %jx",
  305                             (uintmax_t)start);
  306                 if (mem_affinity[i].end >= end) {
  307                         _vm_phys_create_seg(start, end,
  308                             mem_affinity[i].domain);
  309                         break;
  310                 }
  311                 _vm_phys_create_seg(start, mem_affinity[i].end,
  312                     mem_affinity[i].domain);
  313                 start = mem_affinity[i].end;
  314         }
  315 }
  316 
  317 /*
  318  * Add a physical memory segment.
  319  */
  320 void
  321 vm_phys_add_seg(vm_paddr_t start, vm_paddr_t end)
  322 {
  323         vm_paddr_t paddr;
  324 
  325         KASSERT((start & PAGE_MASK) == 0,
  326             ("vm_phys_define_seg: start is not page aligned"));
  327         KASSERT((end & PAGE_MASK) == 0,
  328             ("vm_phys_define_seg: end is not page aligned"));
  329 
  330         /*
  331          * Split the physical memory segment if it spans two or more free
  332          * list boundaries.
  333          */
  334         paddr = start;
  335 #ifdef  VM_FREELIST_ISADMA
  336         if (paddr < VM_ISADMA_BOUNDARY && end > VM_ISADMA_BOUNDARY) {
  337                 vm_phys_create_seg(paddr, VM_ISADMA_BOUNDARY);
  338                 paddr = VM_ISADMA_BOUNDARY;
  339         }
  340 #endif
  341 #ifdef  VM_FREELIST_LOWMEM
  342         if (paddr < VM_LOWMEM_BOUNDARY && end > VM_LOWMEM_BOUNDARY) {
  343                 vm_phys_create_seg(paddr, VM_LOWMEM_BOUNDARY);
  344                 paddr = VM_LOWMEM_BOUNDARY;
  345         }
  346 #endif
  347 #ifdef  VM_FREELIST_DMA32
  348         if (paddr < VM_DMA32_BOUNDARY && end > VM_DMA32_BOUNDARY) {
  349                 vm_phys_create_seg(paddr, VM_DMA32_BOUNDARY);
  350                 paddr = VM_DMA32_BOUNDARY;
  351         }
  352 #endif
  353         vm_phys_create_seg(paddr, end);
  354 }
  355 
  356 /*
  357  * Initialize the physical memory allocator.
  358  *
  359  * Requires that vm_page_array is initialized!
  360  */
  361 void
  362 vm_phys_init(void)
  363 {
  364         struct vm_freelist *fl;
  365         struct vm_phys_seg *seg;
  366         u_long npages;
  367         int dom, flind, freelist, oind, pind, segind;
  368 
  369         /*
  370          * Compute the number of free lists, and generate the mapping from the
  371          * manifest constants VM_FREELIST_* to the free list indices.
  372          *
  373          * Initially, the entries of vm_freelist_to_flind[] are set to either
  374          * 0 or 1 to indicate which free lists should be created.
  375          */
  376         npages = 0;
  377         for (segind = vm_phys_nsegs - 1; segind >= 0; segind--) {
  378                 seg = &vm_phys_segs[segind];
  379 #ifdef  VM_FREELIST_ISADMA
  380                 if (seg->end <= VM_ISADMA_BOUNDARY)
  381                         vm_freelist_to_flind[VM_FREELIST_ISADMA] = 1;
  382                 else
  383 #endif
  384 #ifdef  VM_FREELIST_LOWMEM
  385                 if (seg->end <= VM_LOWMEM_BOUNDARY)
  386                         vm_freelist_to_flind[VM_FREELIST_LOWMEM] = 1;
  387                 else
  388 #endif
  389 #ifdef  VM_FREELIST_DMA32
  390                 if (
  391 #ifdef  VM_DMA32_NPAGES_THRESHOLD
  392                     /*
  393                      * Create the DMA32 free list only if the amount of
  394                      * physical memory above physical address 4G exceeds the
  395                      * given threshold.
  396                      */
  397                     npages > VM_DMA32_NPAGES_THRESHOLD &&
  398 #endif
  399                     seg->end <= VM_DMA32_BOUNDARY)
  400                         vm_freelist_to_flind[VM_FREELIST_DMA32] = 1;
  401                 else
  402 #endif
  403                 {
  404                         npages += atop(seg->end - seg->start);
  405                         vm_freelist_to_flind[VM_FREELIST_DEFAULT] = 1;
  406                 }
  407         }
  408         /* Change each entry into a running total of the free lists. */
  409         for (freelist = 1; freelist < VM_NFREELIST; freelist++) {
  410                 vm_freelist_to_flind[freelist] +=
  411                     vm_freelist_to_flind[freelist - 1];
  412         }
  413         vm_nfreelists = vm_freelist_to_flind[VM_NFREELIST - 1];
  414         KASSERT(vm_nfreelists > 0, ("vm_phys_init: no free lists"));
  415         /* Change each entry into a free list index. */
  416         for (freelist = 0; freelist < VM_NFREELIST; freelist++)
  417                 vm_freelist_to_flind[freelist]--;
  418 
  419         /*
  420          * Initialize the first_page and free_queues fields of each physical
  421          * memory segment.
  422          */
  423 #ifdef VM_PHYSSEG_SPARSE
  424         npages = 0;
  425 #endif
  426         for (segind = 0; segind < vm_phys_nsegs; segind++) {
  427                 seg = &vm_phys_segs[segind];
  428 #ifdef VM_PHYSSEG_SPARSE
  429                 seg->first_page = &vm_page_array[npages];
  430                 npages += atop(seg->end - seg->start);
  431 #else
  432                 seg->first_page = PHYS_TO_VM_PAGE(seg->start);
  433 #endif
  434 #ifdef  VM_FREELIST_ISADMA
  435                 if (seg->end <= VM_ISADMA_BOUNDARY) {
  436                         flind = vm_freelist_to_flind[VM_FREELIST_ISADMA];
  437                         KASSERT(flind >= 0,
  438                             ("vm_phys_init: ISADMA flind < 0"));
  439                 } else
  440 #endif
  441 #ifdef  VM_FREELIST_LOWMEM
  442                 if (seg->end <= VM_LOWMEM_BOUNDARY) {
  443                         flind = vm_freelist_to_flind[VM_FREELIST_LOWMEM];
  444                         KASSERT(flind >= 0,
  445                             ("vm_phys_init: LOWMEM flind < 0"));
  446                 } else
  447 #endif
  448 #ifdef  VM_FREELIST_DMA32
  449                 if (seg->end <= VM_DMA32_BOUNDARY) {
  450                         flind = vm_freelist_to_flind[VM_FREELIST_DMA32];
  451                         KASSERT(flind >= 0,
  452                             ("vm_phys_init: DMA32 flind < 0"));
  453                 } else
  454 #endif
  455                 {
  456                         flind = vm_freelist_to_flind[VM_FREELIST_DEFAULT];
  457                         KASSERT(flind >= 0,
  458                             ("vm_phys_init: DEFAULT flind < 0"));
  459                 }
  460                 seg->free_queues = &vm_phys_free_queues[seg->domain][flind];
  461         }
  462 
  463         /*
  464          * Initialize the free queues.
  465          */
  466         for (dom = 0; dom < vm_ndomains; dom++) {
  467                 for (flind = 0; flind < vm_nfreelists; flind++) {
  468                         for (pind = 0; pind < VM_NFREEPOOL; pind++) {
  469                                 fl = vm_phys_free_queues[dom][flind][pind];
  470                                 for (oind = 0; oind < VM_NFREEORDER; oind++)
  471                                         TAILQ_INIT(&fl[oind].pl);
  472                         }
  473                 }
  474         }
  475         mtx_init(&vm_phys_fictitious_reg_mtx, "vmfctr", NULL, MTX_DEF);
  476 }
  477 
  478 /*
  479  * Split a contiguous, power of two-sized set of physical pages.
  480  */
  481 static __inline void
  482 vm_phys_split_pages(vm_page_t m, int oind, struct vm_freelist *fl, int order)
  483 {
  484         vm_page_t m_buddy;
  485 
  486         while (oind > order) {
  487                 oind--;
  488                 m_buddy = &m[1 << oind];
  489                 KASSERT(m_buddy->order == VM_NFREEORDER,
  490                     ("vm_phys_split_pages: page %p has unexpected order %d",
  491                     m_buddy, m_buddy->order));
  492                 vm_freelist_add(fl, m_buddy, oind, 0);
  493         }
  494 }
  495 
  496 /*
  497  * Initialize a physical page and add it to the free lists.
  498  */
  499 void
  500 vm_phys_add_page(vm_paddr_t pa)
  501 {
  502         vm_page_t m;
  503         struct vm_domain *vmd;
  504 
  505         cnt.v_page_count++;
  506         m = vm_phys_paddr_to_vm_page(pa);
  507         m->busy_lock = VPB_UNBUSIED;
  508         m->phys_addr = pa;
  509         m->queue = PQ_NONE;
  510         m->segind = vm_phys_paddr_to_segind(pa);
  511         vmd = vm_phys_domain(m);
  512         vmd->vmd_page_count++;
  513         vmd->vmd_segs |= 1UL << m->segind;
  514         m->flags = PG_FREE;
  515         KASSERT(m->order == VM_NFREEORDER,
  516             ("vm_phys_add_page: page %p has unexpected order %d",
  517             m, m->order));
  518         m->pool = VM_FREEPOOL_DEFAULT;
  519         pmap_page_init(m);
  520         mtx_lock(&vm_page_queue_free_mtx);
  521         vm_phys_freecnt_adj(m, 1);
  522         vm_phys_free_pages(m, 0);
  523         mtx_unlock(&vm_page_queue_free_mtx);
  524 }
  525 
  526 /*
  527  * Allocate a contiguous, power of two-sized set of physical pages
  528  * from the free lists.
  529  *
  530  * The free page queues must be locked.
  531  */
  532 vm_page_t
  533 vm_phys_alloc_pages(int pool, int order)
  534 {
  535         vm_page_t m;
  536         int dom, domain, flind;
  537 
  538         KASSERT(pool < VM_NFREEPOOL,
  539             ("vm_phys_alloc_pages: pool %d is out of range", pool));
  540         KASSERT(order < VM_NFREEORDER,
  541             ("vm_phys_alloc_pages: order %d is out of range", order));
  542 
  543         for (dom = 0; dom < vm_ndomains; dom++) {
  544                 domain = vm_rr_selectdomain();
  545                 for (flind = 0; flind < vm_nfreelists; flind++) {
  546                         m = vm_phys_alloc_domain_pages(domain, flind, pool,
  547                             order);
  548                         if (m != NULL)
  549                                 return (m);
  550                 }
  551         }
  552         return (NULL);
  553 }
  554 
  555 /*
  556  * Allocate a contiguous, power of two-sized set of physical pages from the
  557  * specified free list.  The free list must be specified using one of the
  558  * manifest constants VM_FREELIST_*.
  559  *
  560  * The free page queues must be locked.
  561  */
  562 vm_page_t
  563 vm_phys_alloc_freelist_pages(int freelist, int pool, int order)
  564 {
  565         vm_page_t m;
  566         int dom, domain;
  567 
  568         KASSERT(freelist < VM_NFREELIST,
  569             ("vm_phys_alloc_freelist_pages: freelist %d is out of range",
  570             freelist));
  571         KASSERT(pool < VM_NFREEPOOL,
  572             ("vm_phys_alloc_freelist_pages: pool %d is out of range", pool));
  573         KASSERT(order < VM_NFREEORDER,
  574             ("vm_phys_alloc_freelist_pages: order %d is out of range", order));
  575         for (dom = 0; dom < vm_ndomains; dom++) {
  576                 domain = vm_rr_selectdomain();
  577                 m = vm_phys_alloc_domain_pages(domain,
  578                     vm_freelist_to_flind[freelist], pool, order);
  579                 if (m != NULL)
  580                         return (m);
  581         }
  582         return (NULL);
  583 }
  584 
  585 static vm_page_t
  586 vm_phys_alloc_domain_pages(int domain, int flind, int pool, int order)
  587 {       
  588         struct vm_freelist *fl;
  589         struct vm_freelist *alt;
  590         int oind, pind;
  591         vm_page_t m;
  592 
  593         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
  594         fl = &vm_phys_free_queues[domain][flind][pool][0];
  595         for (oind = order; oind < VM_NFREEORDER; oind++) {
  596                 m = TAILQ_FIRST(&fl[oind].pl);
  597                 if (m != NULL) {
  598                         vm_freelist_rem(fl, m, oind);
  599                         vm_phys_split_pages(m, oind, fl, order);
  600                         return (m);
  601                 }
  602         }
  603 
  604         /*
  605          * The given pool was empty.  Find the largest
  606          * contiguous, power-of-two-sized set of pages in any
  607          * pool.  Transfer these pages to the given pool, and
  608          * use them to satisfy the allocation.
  609          */
  610         for (oind = VM_NFREEORDER - 1; oind >= order; oind--) {
  611                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
  612                         alt = &vm_phys_free_queues[domain][flind][pind][0];
  613                         m = TAILQ_FIRST(&alt[oind].pl);
  614                         if (m != NULL) {
  615                                 vm_freelist_rem(alt, m, oind);
  616                                 vm_phys_set_pool(pool, m, oind);
  617                                 vm_phys_split_pages(m, oind, fl, order);
  618                                 return (m);
  619                         }
  620                 }
  621         }
  622         return (NULL);
  623 }
  624 
  625 /*
  626  * Find the vm_page corresponding to the given physical address.
  627  */
  628 vm_page_t
  629 vm_phys_paddr_to_vm_page(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 (&seg->first_page[atop(pa - seg->start)]);
  638         }
  639         return (NULL);
  640 }
  641 
  642 vm_page_t
  643 vm_phys_fictitious_to_vm_page(vm_paddr_t pa)
  644 {
  645         struct vm_phys_fictitious_seg *seg;
  646         vm_page_t m;
  647         int segind;
  648 
  649         m = NULL;
  650         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
  651                 seg = &vm_phys_fictitious_segs[segind];
  652                 if (pa >= seg->start && pa < seg->end) {
  653                         m = &seg->first_page[atop(pa - seg->start)];
  654                         KASSERT((m->flags & PG_FICTITIOUS) != 0,
  655                             ("%p not fictitious", m));
  656                         break;
  657                 }
  658         }
  659         return (m);
  660 }
  661 
  662 int
  663 vm_phys_fictitious_reg_range(vm_paddr_t start, vm_paddr_t end,
  664     vm_memattr_t memattr)
  665 {
  666         struct vm_phys_fictitious_seg *seg;
  667         vm_page_t fp;
  668         long i, page_count;
  669         int segind;
  670 #ifdef VM_PHYSSEG_DENSE
  671         long pi;
  672         boolean_t malloced;
  673 #endif
  674 
  675         page_count = (end - start) / PAGE_SIZE;
  676 
  677 #ifdef VM_PHYSSEG_DENSE
  678         pi = atop(start);
  679         if (pi >= first_page && pi < vm_page_array_size + first_page) {
  680                 if (atop(end) >= vm_page_array_size + first_page)
  681                         return (EINVAL);
  682                 fp = &vm_page_array[pi - first_page];
  683                 malloced = FALSE;
  684         } else
  685 #endif
  686         {
  687                 fp = malloc(page_count * sizeof(struct vm_page), M_FICT_PAGES,
  688                     M_WAITOK | M_ZERO);
  689 #ifdef VM_PHYSSEG_DENSE
  690                 malloced = TRUE;
  691 #endif
  692         }
  693         for (i = 0; i < page_count; i++) {
  694                 vm_page_initfake(&fp[i], start + PAGE_SIZE * i, memattr);
  695                 fp[i].oflags &= ~VPO_UNMANAGED;
  696                 fp[i].busy_lock = VPB_UNBUSIED;
  697         }
  698         mtx_lock(&vm_phys_fictitious_reg_mtx);
  699         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
  700                 seg = &vm_phys_fictitious_segs[segind];
  701                 if (seg->start == 0 && seg->end == 0) {
  702                         seg->start = start;
  703                         seg->end = end;
  704                         seg->first_page = fp;
  705                         mtx_unlock(&vm_phys_fictitious_reg_mtx);
  706                         return (0);
  707                 }
  708         }
  709         mtx_unlock(&vm_phys_fictitious_reg_mtx);
  710 #ifdef VM_PHYSSEG_DENSE
  711         if (malloced)
  712 #endif
  713                 free(fp, M_FICT_PAGES);
  714         return (EBUSY);
  715 }
  716 
  717 void
  718 vm_phys_fictitious_unreg_range(vm_paddr_t start, vm_paddr_t end)
  719 {
  720         struct vm_phys_fictitious_seg *seg;
  721         vm_page_t fp;
  722         int segind;
  723 #ifdef VM_PHYSSEG_DENSE
  724         long pi;
  725 #endif
  726 
  727 #ifdef VM_PHYSSEG_DENSE
  728         pi = atop(start);
  729 #endif
  730 
  731         mtx_lock(&vm_phys_fictitious_reg_mtx);
  732         for (segind = 0; segind < VM_PHYS_FICTITIOUS_NSEGS; segind++) {
  733                 seg = &vm_phys_fictitious_segs[segind];
  734                 if (seg->start == start && seg->end == end) {
  735                         seg->start = seg->end = 0;
  736                         fp = seg->first_page;
  737                         seg->first_page = NULL;
  738                         mtx_unlock(&vm_phys_fictitious_reg_mtx);
  739 #ifdef VM_PHYSSEG_DENSE
  740                         if (pi < first_page || atop(end) >= vm_page_array_size)
  741 #endif
  742                                 free(fp, M_FICT_PAGES);
  743                         return;
  744                 }
  745         }
  746         mtx_unlock(&vm_phys_fictitious_reg_mtx);
  747         KASSERT(0, ("Unregistering not registered fictitious range"));
  748 }
  749 
  750 /*
  751  * Find the segment containing the given physical address.
  752  */
  753 static int
  754 vm_phys_paddr_to_segind(vm_paddr_t pa)
  755 {
  756         struct vm_phys_seg *seg;
  757         int segind;
  758 
  759         for (segind = 0; segind < vm_phys_nsegs; segind++) {
  760                 seg = &vm_phys_segs[segind];
  761                 if (pa >= seg->start && pa < seg->end)
  762                         return (segind);
  763         }
  764         panic("vm_phys_paddr_to_segind: paddr %#jx is not in any segment" ,
  765             (uintmax_t)pa);
  766 }
  767 
  768 /*
  769  * Free a contiguous, power of two-sized set of physical pages.
  770  *
  771  * The free page queues must be locked.
  772  */
  773 void
  774 vm_phys_free_pages(vm_page_t m, int order)
  775 {
  776         struct vm_freelist *fl;
  777         struct vm_phys_seg *seg;
  778         vm_paddr_t pa;
  779         vm_page_t m_buddy;
  780 
  781         KASSERT(m->order == VM_NFREEORDER,
  782             ("vm_phys_free_pages: page %p has unexpected order %d",
  783             m, m->order));
  784         KASSERT(m->pool < VM_NFREEPOOL,
  785             ("vm_phys_free_pages: page %p has unexpected pool %d",
  786             m, m->pool));
  787         KASSERT(order < VM_NFREEORDER,
  788             ("vm_phys_free_pages: order %d is out of range", order));
  789         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
  790         seg = &vm_phys_segs[m->segind];
  791         if (order < VM_NFREEORDER - 1) {
  792                 pa = VM_PAGE_TO_PHYS(m);
  793                 do {
  794                         pa ^= ((vm_paddr_t)1 << (PAGE_SHIFT + order));
  795                         if (pa < seg->start || pa >= seg->end)
  796                                 break;
  797                         m_buddy = &seg->first_page[atop(pa - seg->start)];
  798                         if (m_buddy->order != order)
  799                                 break;
  800                         fl = (*seg->free_queues)[m_buddy->pool];
  801                         vm_freelist_rem(fl, m_buddy, order);
  802                         if (m_buddy->pool != m->pool)
  803                                 vm_phys_set_pool(m->pool, m_buddy, order);
  804                         order++;
  805                         pa &= ~(((vm_paddr_t)1 << (PAGE_SHIFT + order)) - 1);
  806                         m = &seg->first_page[atop(pa - seg->start)];
  807                 } while (order < VM_NFREEORDER - 1);
  808         }
  809         fl = (*seg->free_queues)[m->pool];
  810         vm_freelist_add(fl, m, order, 1);
  811 }
  812 
  813 /*
  814  * Free a contiguous, arbitrarily sized set of physical pages.
  815  *
  816  * The free page queues must be locked.
  817  */
  818 void
  819 vm_phys_free_contig(vm_page_t m, u_long npages)
  820 {
  821         u_int n;
  822         int order;
  823 
  824         /*
  825          * Avoid unnecessary coalescing by freeing the pages in the largest
  826          * possible power-of-two-sized subsets.
  827          */
  828         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
  829         for (;; npages -= n) {
  830                 /*
  831                  * Unsigned "min" is used here so that "order" is assigned
  832                  * "VM_NFREEORDER - 1" when "m"'s physical address is zero
  833                  * or the low-order bits of its physical address are zero
  834                  * because the size of a physical address exceeds the size of
  835                  * a long.
  836                  */
  837                 order = min(ffsl(VM_PAGE_TO_PHYS(m) >> PAGE_SHIFT) - 1,
  838                     VM_NFREEORDER - 1);
  839                 n = 1 << order;
  840                 if (npages < n)
  841                         break;
  842                 vm_phys_free_pages(m, order);
  843                 m += n;
  844         }
  845         /* The residual "npages" is less than "1 << (VM_NFREEORDER - 1)". */
  846         for (; npages > 0; npages -= n) {
  847                 order = flsl(npages) - 1;
  848                 n = 1 << order;
  849                 vm_phys_free_pages(m, order);
  850                 m += n;
  851         }
  852 }
  853 
  854 /*
  855  * Set the pool for a contiguous, power of two-sized set of physical pages. 
  856  */
  857 void
  858 vm_phys_set_pool(int pool, vm_page_t m, int order)
  859 {
  860         vm_page_t m_tmp;
  861 
  862         for (m_tmp = m; m_tmp < &m[1 << order]; m_tmp++)
  863                 m_tmp->pool = pool;
  864 }
  865 
  866 /*
  867  * Search for the given physical page "m" in the free lists.  If the search
  868  * succeeds, remove "m" from the free lists and return TRUE.  Otherwise, return
  869  * FALSE, indicating that "m" is not in the free lists.
  870  *
  871  * The free page queues must be locked.
  872  */
  873 boolean_t
  874 vm_phys_unfree_page(vm_page_t m)
  875 {
  876         struct vm_freelist *fl;
  877         struct vm_phys_seg *seg;
  878         vm_paddr_t pa, pa_half;
  879         vm_page_t m_set, m_tmp;
  880         int order;
  881 
  882         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
  883 
  884         /*
  885          * First, find the contiguous, power of two-sized set of free
  886          * physical pages containing the given physical page "m" and
  887          * assign it to "m_set".
  888          */
  889         seg = &vm_phys_segs[m->segind];
  890         for (m_set = m, order = 0; m_set->order == VM_NFREEORDER &&
  891             order < VM_NFREEORDER - 1; ) {
  892                 order++;
  893                 pa = m->phys_addr & (~(vm_paddr_t)0 << (PAGE_SHIFT + order));
  894                 if (pa >= seg->start)
  895                         m_set = &seg->first_page[atop(pa - seg->start)];
  896                 else
  897                         return (FALSE);
  898         }
  899         if (m_set->order < order)
  900                 return (FALSE);
  901         if (m_set->order == VM_NFREEORDER)
  902                 return (FALSE);
  903         KASSERT(m_set->order < VM_NFREEORDER,
  904             ("vm_phys_unfree_page: page %p has unexpected order %d",
  905             m_set, m_set->order));
  906 
  907         /*
  908          * Next, remove "m_set" from the free lists.  Finally, extract
  909          * "m" from "m_set" using an iterative algorithm: While "m_set"
  910          * is larger than a page, shrink "m_set" by returning the half
  911          * of "m_set" that does not contain "m" to the free lists.
  912          */
  913         fl = (*seg->free_queues)[m_set->pool];
  914         order = m_set->order;
  915         vm_freelist_rem(fl, m_set, order);
  916         while (order > 0) {
  917                 order--;
  918                 pa_half = m_set->phys_addr ^ (1 << (PAGE_SHIFT + order));
  919                 if (m->phys_addr < pa_half)
  920                         m_tmp = &seg->first_page[atop(pa_half - seg->start)];
  921                 else {
  922                         m_tmp = m_set;
  923                         m_set = &seg->first_page[atop(pa_half - seg->start)];
  924                 }
  925                 vm_freelist_add(fl, m_tmp, order, 0);
  926         }
  927         KASSERT(m_set == m, ("vm_phys_unfree_page: fatal inconsistency"));
  928         return (TRUE);
  929 }
  930 
  931 /*
  932  * Try to zero one physical page.  Used by an idle priority thread.
  933  */
  934 boolean_t
  935 vm_phys_zero_pages_idle(void)
  936 {
  937         static struct vm_freelist *fl;
  938         static int flind, oind, pind;
  939         vm_page_t m, m_tmp;
  940         int domain;
  941 
  942         domain = vm_rr_selectdomain();
  943         fl = vm_phys_free_queues[domain][0][0];
  944         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
  945         for (;;) {
  946                 TAILQ_FOREACH_REVERSE(m, &fl[oind].pl, pglist, plinks.q) {
  947                         for (m_tmp = m; m_tmp < &m[1 << oind]; m_tmp++) {
  948                                 if ((m_tmp->flags & (PG_CACHED | PG_ZERO)) == 0) {
  949                                         vm_phys_unfree_page(m_tmp);
  950                                         vm_phys_freecnt_adj(m, -1);
  951                                         mtx_unlock(&vm_page_queue_free_mtx);
  952                                         pmap_zero_page_idle(m_tmp);
  953                                         m_tmp->flags |= PG_ZERO;
  954                                         mtx_lock(&vm_page_queue_free_mtx);
  955                                         vm_phys_freecnt_adj(m, 1);
  956                                         vm_phys_free_pages(m_tmp, 0);
  957                                         vm_page_zero_count++;
  958                                         cnt_prezero++;
  959                                         return (TRUE);
  960                                 }
  961                         }
  962                 }
  963                 oind++;
  964                 if (oind == VM_NFREEORDER) {
  965                         oind = 0;
  966                         pind++;
  967                         if (pind == VM_NFREEPOOL) {
  968                                 pind = 0;
  969                                 flind++;
  970                                 if (flind == vm_nfreelists)
  971                                         flind = 0;
  972                         }
  973                         fl = vm_phys_free_queues[domain][flind][pind];
  974                 }
  975         }
  976 }
  977 
  978 /*
  979  * Allocate a contiguous set of physical pages of the given size
  980  * "npages" from the free lists.  All of the physical pages must be at
  981  * or above the given physical address "low" and below the given
  982  * physical address "high".  The given value "alignment" determines the
  983  * alignment of the first physical page in the set.  If the given value
  984  * "boundary" is non-zero, then the set of physical pages cannot cross
  985  * any physical address boundary that is a multiple of that value.  Both
  986  * "alignment" and "boundary" must be a power of two.
  987  */
  988 vm_page_t
  989 vm_phys_alloc_contig(u_long npages, vm_paddr_t low, vm_paddr_t high,
  990     u_long alignment, vm_paddr_t boundary)
  991 {
  992         struct vm_freelist *fl;
  993         struct vm_phys_seg *seg;
  994         vm_paddr_t pa, pa_last, size;
  995         vm_page_t m, m_ret;
  996         u_long npages_end;
  997         int dom, domain, flind, oind, order, pind;
  998 
  999         mtx_assert(&vm_page_queue_free_mtx, MA_OWNED);
 1000         size = npages << PAGE_SHIFT;
 1001         KASSERT(size != 0,
 1002             ("vm_phys_alloc_contig: size must not be 0"));
 1003         KASSERT((alignment & (alignment - 1)) == 0,
 1004             ("vm_phys_alloc_contig: alignment must be a power of 2"));
 1005         KASSERT((boundary & (boundary - 1)) == 0,
 1006             ("vm_phys_alloc_contig: boundary must be a power of 2"));
 1007         /* Compute the queue that is the best fit for npages. */
 1008         for (order = 0; (1 << order) < npages; order++);
 1009         dom = 0;
 1010 restartdom:
 1011         domain = vm_rr_selectdomain();
 1012         for (flind = 0; flind < vm_nfreelists; flind++) {
 1013                 for (oind = min(order, VM_NFREEORDER - 1); oind < VM_NFREEORDER; oind++) {
 1014                         for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 1015                                 fl = &vm_phys_free_queues[domain][flind][pind][0];
 1016                                 TAILQ_FOREACH(m_ret, &fl[oind].pl, plinks.q) {
 1017                                         /*
 1018                                          * A free list may contain physical pages
 1019                                          * from one or more segments.
 1020                                          */
 1021                                         seg = &vm_phys_segs[m_ret->segind];
 1022                                         if (seg->start > high ||
 1023                                             low >= seg->end)
 1024                                                 continue;
 1025 
 1026                                         /*
 1027                                          * Is the size of this allocation request
 1028                                          * larger than the largest block size?
 1029                                          */
 1030                                         if (order >= VM_NFREEORDER) {
 1031                                                 /*
 1032                                                  * Determine if a sufficient number
 1033                                                  * of subsequent blocks to satisfy
 1034                                                  * the allocation request are free.
 1035                                                  */
 1036                                                 pa = VM_PAGE_TO_PHYS(m_ret);
 1037                                                 pa_last = pa + size;
 1038                                                 for (;;) {
 1039                                                         pa += 1 << (PAGE_SHIFT + VM_NFREEORDER - 1);
 1040                                                         if (pa >= pa_last)
 1041                                                                 break;
 1042                                                         if (pa < seg->start ||
 1043                                                             pa >= seg->end)
 1044                                                                 break;
 1045                                                         m = &seg->first_page[atop(pa - seg->start)];
 1046                                                         if (m->order != VM_NFREEORDER - 1)
 1047                                                                 break;
 1048                                                 }
 1049                                                 /* If not, continue to the next block. */
 1050                                                 if (pa < pa_last)
 1051                                                         continue;
 1052                                         }
 1053 
 1054                                         /*
 1055                                          * Determine if the blocks are within the given range,
 1056                                          * satisfy the given alignment, and do not cross the
 1057                                          * given boundary.
 1058                                          */
 1059                                         pa = VM_PAGE_TO_PHYS(m_ret);
 1060                                         if (pa >= low &&
 1061                                             pa + size <= high &&
 1062                                             (pa & (alignment - 1)) == 0 &&
 1063                                             ((pa ^ (pa + size - 1)) & ~(boundary - 1)) == 0)
 1064                                                 goto done;
 1065                                 }
 1066                         }
 1067                 }
 1068         }
 1069         if (++dom < vm_ndomains)
 1070                 goto restartdom;
 1071         return (NULL);
 1072 done:
 1073         for (m = m_ret; m < &m_ret[npages]; m = &m[1 << oind]) {
 1074                 fl = (*seg->free_queues)[m->pool];
 1075                 vm_freelist_rem(fl, m, m->order);
 1076         }
 1077         if (m_ret->pool != VM_FREEPOOL_DEFAULT)
 1078                 vm_phys_set_pool(VM_FREEPOOL_DEFAULT, m_ret, oind);
 1079         fl = (*seg->free_queues)[m_ret->pool];
 1080         vm_phys_split_pages(m_ret, oind, fl, order);
 1081         /* Return excess pages to the free lists. */
 1082         npages_end = roundup2(npages, 1 << imin(oind, order));
 1083         if (npages < npages_end)
 1084                 vm_phys_free_contig(&m_ret[npages], npages_end - npages);
 1085         return (m_ret);
 1086 }
 1087 
 1088 #ifdef DDB
 1089 /*
 1090  * Show the number of physical pages in each of the free lists.
 1091  */
 1092 DB_SHOW_COMMAND(freepages, db_show_freepages)
 1093 {
 1094         struct vm_freelist *fl;
 1095         int flind, oind, pind, dom;
 1096 
 1097         for (dom = 0; dom < vm_ndomains; dom++) {
 1098                 db_printf("DOMAIN: %d\n", dom);
 1099                 for (flind = 0; flind < vm_nfreelists; flind++) {
 1100                         db_printf("FREE LIST %d:\n"
 1101                             "\n  ORDER (SIZE)  |  NUMBER"
 1102                             "\n              ", flind);
 1103                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
 1104                                 db_printf("  |  POOL %d", pind);
 1105                         db_printf("\n--            ");
 1106                         for (pind = 0; pind < VM_NFREEPOOL; pind++)
 1107                                 db_printf("-- --      ");
 1108                         db_printf("--\n");
 1109                         for (oind = VM_NFREEORDER - 1; oind >= 0; oind--) {
 1110                                 db_printf("  %2.2d (%6.6dK)", oind,
 1111                                     1 << (PAGE_SHIFT - 10 + oind));
 1112                                 for (pind = 0; pind < VM_NFREEPOOL; pind++) {
 1113                                 fl = vm_phys_free_queues[dom][flind][pind];
 1114                                         db_printf("  |  %6.6d", fl[oind].lcnt);
 1115                                 }
 1116                                 db_printf("\n");
 1117                         }
 1118                         db_printf("\n");
 1119                 }
 1120                 db_printf("\n");
 1121         }
 1122 }
 1123 #endif
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FreeBSD/Linux Kernel Cross Reference sys/vm/vm_phys.c

FreeBSD/Linux Kernel Cross Reference
sys/vm/vm_phys.c
