servers/vm/mem_anon_contig.c

   1
   2 /* This file implements the methods of physically contiguous anonymous memory. */
   3
   4 #include <assert.h>
   5
   6 #include "proto.h"
   7 #include "vm.h"
   8 #include "region.h"
   9 #include "glo.h"
  10
  11 static int anon_contig_reference(struct phys_region *pr);
  12 static int anon_contig_unreference(struct phys_region *pr);
  13 static int anon_contig_pagefault(struct vmproc *vmp, struct vir_region *region,
  14         struct phys_region *ph, int write);
  15 static int anon_contig_sanitycheck(struct phys_region *pr, char *file, int line);
  16 static int anon_contig_writable(struct phys_region *pr);
  17 static int anon_contig_resize(struct vmproc *vmp, struct vir_region *vr, vir_bytes l);
  18 static int anon_contig_new(struct vir_region *vr);
  19
  20 struct mem_type mem_type_anon_contig = {
  21         .name = "anonymous memory (physically contiguous)",
  22         .ev_new = anon_contig_new,
  23         .ev_reference = anon_contig_reference,
  24         .ev_unreference = anon_contig_unreference,
  25         .ev_pagefault = anon_contig_pagefault,
  26         .ev_resize = anon_contig_resize,
  27         .ev_sanitycheck = anon_contig_sanitycheck,
  28         .writable = anon_contig_writable
  29 };
  30
  31 static int anon_contig_pagefault(struct vmproc *vmp, struct vir_region *region,
  32         struct phys_region *ph, int write)
  33 {
  34         panic("anon_contig_pagefault: pagefault cannot happen");
  35 }
  36
  37 static int anon_contig_new(struct vir_region *region)
  38 {
  39         u32_t allocflags;
  40         phys_bytes new_pages, new_page_cl, cur_ph;
  41         int p, pages;
  42
  43         allocflags = vrallocflags(region->flags);
  44
  45         pages = region->length/VM_PAGE_SIZE;
  46
  47         assert(physregions(region) == 0);
  48
  49         for(p = 0; p < pages; p++) {
  50                 struct phys_block *pb = pb_new(MAP_NONE);
  51                 struct phys_region *pr = NULL;
  52                 if(pb)
  53                         pr = pb_reference(pb, p * VM_PAGE_SIZE, region);
  54                 if(!pr) {
  55                         if(pb) pb_free(pb);
  56                         map_free(region);
  57                         return ENOMEM;
  58                 }
  59         }
  60
  61         assert(physregions(region) == pages);
  62
  63         if((new_page_cl = alloc_mem(pages, allocflags)) == NO_MEM) {
  64                 map_free(region);
  65                 return ENOMEM;
  66         }
  67
  68         cur_ph = new_pages = CLICK2ABS(new_page_cl);
  69
  70         for(p = 0; p < pages; p++) {
  71                 struct phys_region *pr = physblock_get(region, p * VM_PAGE_SIZE);
  72                 assert(pr);
  73                 assert(pr->ph);
  74                 assert(pr->ph->phys == MAP_NONE);
  75                 assert(pr->offset == p * VM_PAGE_SIZE);
  76                 pr->ph->phys = cur_ph + pr->offset;
  77         }
  78
  79         return OK;
  80 }
  81
  82 static int anon_contig_resize(struct vmproc *vmp, struct vir_region *vr, vir_bytes l)
  83 {
  84         printf("VM: cannot resize physically contiguous memory.\n");
  85         return ENOMEM;
  86 }
  87
  88 static int anon_contig_reference(struct phys_region *pr)
  89 {
  90         printf("VM: cannot fork with physically contig memory.\n");
  91         return ENOMEM;
  92 }
  93
  94 /* Methods inherited from the anonymous memory methods. */
  95
  96 static int anon_contig_unreference(struct phys_region *pr)
  97 {
  98         return mem_type_anon.ev_unreference(pr);
  99 }
 100
 101 static int anon_contig_sanitycheck(struct phys_region *pr, char *file, int line)
 102 {
 103         return mem_type_anon.ev_sanitycheck(pr, file, line);
 104 }
 105
 106 static int anon_contig_writable(struct phys_region *pr)
 107 {
 108         return mem_type_anon.writable(pr);
 109 }
 110