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         physr_iter iter;
  43
  44         allocflags = vrallocflags(region->flags);
  45
  46         pages = region->length/VM_PAGE_SIZE;
  47
  48         assert(physregions(region) == 0);
  49
  50         for(p = 0; p < pages; p++) {
  51                 struct phys_block *pb = pb_new(MAP_NONE);
  52                 struct phys_region *pr = NULL;
  53                 if(pb)
  54                         pr = pb_reference(pb, p * VM_PAGE_SIZE, region);
  55                 if(!pr) {
  56                         if(pb) pb_free(pb);
  57                         map_free(region);
  58                         return ENOMEM;
  59                 }
  60         }
  61
  62         assert(physregions(region) == pages);
  63
  64         if((new_page_cl = alloc_mem(pages, allocflags)) == NO_MEM) {
  65                 map_free(region);
  66                 return ENOMEM;
  67         }
  68
  69         cur_ph = new_pages = CLICK2ABS(new_page_cl);
  70
  71         physr_start_iter_least(region->phys, &iter);
  72
  73         for(p = 0; p < pages; p++) {
  74                 struct phys_region *pr = physr_get_iter(&iter);
  75                 assert(pr);
  76                 assert(pr->ph);
  77                 assert(pr->ph->phys == MAP_NONE);
  78                 assert(pr->offset == p * VM_PAGE_SIZE);
  79                 pr->ph->phys = cur_ph + pr->offset;
  80                 physr_incr_iter(&iter);
  81         }
  82
  83         assert(!physr_get_iter(&iter));
  84
  85         return OK;
  86 }
  87
  88 static int anon_contig_resize(struct vmproc *vmp, struct vir_region *vr, vir_bytes l)
  89 {
  90         printf("VM: cannot resize physically contiguous memory.\n");
  91         return ENOMEM;
  92 }
  93
  94 static int anon_contig_reference(struct phys_region *pr)
  95 {
  96         printf("VM: cannot fork with physically contig memory.\n");
  97         return ENOMEM;
  98 }
  99
 100 /* Methods inherited from the anonymous memory methods. */
 101
 102 static int anon_contig_unreference(struct phys_region *pr)
 103 {
 104         return mem_type_anon.ev_unreference(pr);
 105 }
 106
 107 static int anon_contig_sanitycheck(struct phys_region *pr, char *file, int line)
 108 {
 109         return mem_type_anon.ev_sanitycheck(pr, file, line);
 110 }
 111
 112 static int anon_contig_writable(struct phys_region *pr)
 113 {
 114         return mem_type_anon.writable(pr);
 115 }
 116