minix/servers/vm/mem_anon_contig.c
Ben Gras 29edcad310 vm: replace phys avl by array
. make vm be able to use malloc() by overriding brk()
   and minix_mmap() functions
 . phys regions can then be malloc()ed and free()d instead
   of being in an avl tree, which is slightly faster
 . 'offset' field in phys_region can go too (offset is implied
   by position in array) but leads to bigger code changes
2012-12-26 16:14:41 +00:00

110 lines
2.8 KiB
C

/* This file implements the methods of physically contiguous anonymous memory. */
#include <assert.h>
#include "proto.h"
#include "vm.h"
#include "region.h"
#include "glo.h"
static int anon_contig_reference(struct phys_region *pr);
static int anon_contig_unreference(struct phys_region *pr);
static int anon_contig_pagefault(struct vmproc *vmp, struct vir_region *region,
struct phys_region *ph, int write);
static int anon_contig_sanitycheck(struct phys_region *pr, char *file, int line);
static int anon_contig_writable(struct phys_region *pr);
static int anon_contig_resize(struct vmproc *vmp, struct vir_region *vr, vir_bytes l);
static int anon_contig_new(struct vir_region *vr);
struct mem_type mem_type_anon_contig = {
.name = "anonymous memory (physically contiguous)",
.ev_new = anon_contig_new,
.ev_reference = anon_contig_reference,
.ev_unreference = anon_contig_unreference,
.ev_pagefault = anon_contig_pagefault,
.ev_resize = anon_contig_resize,
.ev_sanitycheck = anon_contig_sanitycheck,
.writable = anon_contig_writable
};
static int anon_contig_pagefault(struct vmproc *vmp, struct vir_region *region,
struct phys_region *ph, int write)
{
panic("anon_contig_pagefault: pagefault cannot happen");
}
static int anon_contig_new(struct vir_region *region)
{
u32_t allocflags;
phys_bytes new_pages, new_page_cl, cur_ph;
int p, pages;
allocflags = vrallocflags(region->flags);
pages = region->length/VM_PAGE_SIZE;
assert(physregions(region) == 0);
for(p = 0; p < pages; p++) {
struct phys_block *pb = pb_new(MAP_NONE);
struct phys_region *pr = NULL;
if(pb)
pr = pb_reference(pb, p * VM_PAGE_SIZE, region);
if(!pr) {
if(pb) pb_free(pb);
map_free(region);
return ENOMEM;
}
}
assert(physregions(region) == pages);
if((new_page_cl = alloc_mem(pages, allocflags)) == NO_MEM) {
map_free(region);
return ENOMEM;
}
cur_ph = new_pages = CLICK2ABS(new_page_cl);
for(p = 0; p < pages; p++) {
struct phys_region *pr = physblock_get(region, p * VM_PAGE_SIZE);
assert(pr);
assert(pr->ph);
assert(pr->ph->phys == MAP_NONE);
assert(pr->offset == p * VM_PAGE_SIZE);
pr->ph->phys = cur_ph + pr->offset;
}
return OK;
}
static int anon_contig_resize(struct vmproc *vmp, struct vir_region *vr, vir_bytes l)
{
printf("VM: cannot resize physically contiguous memory.\n");
return ENOMEM;
}
static int anon_contig_reference(struct phys_region *pr)
{
printf("VM: cannot fork with physically contig memory.\n");
return ENOMEM;
}
/* Methods inherited from the anonymous memory methods. */
static int anon_contig_unreference(struct phys_region *pr)
{
return mem_type_anon.ev_unreference(pr);
}
static int anon_contig_sanitycheck(struct phys_region *pr, char *file, int line)
{
return mem_type_anon.ev_sanitycheck(pr, file, line);
}
static int anon_contig_writable(struct phys_region *pr)
{
return mem_type_anon.writable(pr);
}