minix/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 *, struct phys_region *);
  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, vfs_callback_t cb, void *state,
  15         int len, int *io);
  16 static int anon_contig_sanitycheck(struct phys_region *pr, const char *file, int line);
  17 static int anon_contig_writable(struct phys_region *pr);
  18 static void anon_contig_split(struct vmproc *vmp, struct vir_region *vr,
  19                         struct vir_region *r1, struct vir_region *r2);
  20 static int anon_contig_resize(struct vmproc *vmp, struct vir_region *vr, vir_bytes l);
  21 static int anon_contig_new(struct vir_region *vr);
  22 static int anon_contig_pt_flags(struct vir_region *vr);
  23
  24 struct mem_type mem_type_anon_contig = {
  25         .name = "anonymous memory (physically contiguous)",
  26         .ev_new = anon_contig_new,
  27         .ev_reference = anon_contig_reference,
  28         .ev_unreference = anon_contig_unreference,
  29         .ev_pagefault = anon_contig_pagefault,
  30         .ev_resize = anon_contig_resize,
  31         .ev_split = anon_contig_split,
  32         .ev_sanitycheck = anon_contig_sanitycheck,
  33         .writable = anon_contig_writable,
  34         .pt_flags = anon_contig_pt_flags,
  35 };
  36
  37 static int anon_contig_pt_flags(struct vir_region *vr){
  38 #if defined(__arm__)
  39         return  ARM_VM_PTE_DEVICE;
  40 #else
  41         return  0;
  42 #endif
  43 }
  44
  45 static int anon_contig_pagefault(struct vmproc *vmp, struct vir_region *region,
  46         struct phys_region *ph, int write, vfs_callback_t cb, void *state,
  47         int len, int *io)
  48 {
  49         panic("anon_contig_pagefault: pagefault cannot happen");
  50 }
  51
  52 static int anon_contig_new(struct vir_region *region)
  53 {
  54         u32_t allocflags;
  55         phys_bytes new_pages, new_page_cl, cur_ph;
  56         phys_bytes p, pages;
  57
  58         allocflags = vrallocflags(region->flags);
  59
  60         pages = region->length/VM_PAGE_SIZE;
  61
  62         assert(physregions(region) == 0);
  63
  64         for(p = 0; p < pages; p++) {
  65                 struct phys_block *pb = pb_new(MAP_NONE);
  66                 struct phys_region *pr = NULL;
  67                 if(pb)
  68                         pr = pb_reference(pb, p * VM_PAGE_SIZE, region, &mem_type_anon_contig);
  69                 if(!pr) {
  70                         if(pb) pb_free(pb);
  71                         map_free(region);
  72                         return ENOMEM;
  73                 }
  74         }
  75
  76         assert(physregions(region) == pages);
  77
  78         if((new_page_cl = alloc_mem(pages, allocflags)) == NO_MEM) {
  79                 map_free(region);
  80                 return ENOMEM;
  81         }
  82
  83         cur_ph = new_pages = CLICK2ABS(new_page_cl);
  84
  85         for(p = 0; p < pages; p++) {
  86                 struct phys_region *pr = physblock_get(region, p * VM_PAGE_SIZE);
  87                 assert(pr);
  88                 assert(pr->ph);
  89                 assert(pr->ph->phys == MAP_NONE);
  90                 assert(pr->offset == p * VM_PAGE_SIZE);
  91                 pr->ph->phys = cur_ph + pr->offset;
  92         }
  93
  94         return OK;
  95 }
  96
  97 static int anon_contig_resize(struct vmproc *vmp, struct vir_region *vr, vir_bytes l)
  98 {
  99         printf("VM: cannot resize physically contiguous memory.\n");
 100         return ENOMEM;
 101 }
 102
 103 static int anon_contig_reference(struct phys_region *pr,
 104         struct phys_region *newpr)
 105 {
 106         printf("VM: cannot fork with physically contig memory.\n");
 107         return ENOMEM;
 108 }
 109
 110 /* Methods inherited from the anonymous memory methods. */
 111
 112 static int anon_contig_unreference(struct phys_region *pr)
 113 {
 114         return mem_type_anon.ev_unreference(pr);
 115 }
 116
 117 static int anon_contig_sanitycheck(struct phys_region *pr, const char *file, int line)
 118 {
 119         return mem_type_anon.ev_sanitycheck(pr, file, line);
 120 }
 121
 122 static int anon_contig_writable(struct phys_region *pr)
 123 {
 124         return mem_type_anon.writable(pr);
 125 }
 126
 127 static void anon_contig_split(struct vmproc *vmp, struct vir_region *vr,
 128                         struct vir_region *r1, struct vir_region *r2)
 129 {
 130         return;
 131 }
 132