memorymanager.cc

linux的例子,就是下载后到自己的机子上去运行

#include "system.h"
#include <strings.h>

MemoryManager::MemoryManager(){
	memorymap=new BitMap(NumPhysPages);
}

MemoryManager::~MemoryManager(){
	int i;
	for(i=0;i<NumPhysPages;i++)
		memorymap->Clear(i);
	delete memorymap;
}
bool
MemoryManager::Assign(int page,TranslationEntry *pageTable){
	int i,j=0,k;
	if(page>(k = memorymap->NumClear())) return false;
	for(i=0;i<page;i++){
		j=memorymap->Find();
		pageTable[i].virtualPage=i;
		pageTable[i].physicalPage=j;
		pageTable[i].valid=TRUE;
		pageTable[i].use=FALSE;
		pageTable[i].dirty=FALSE;
		pageTable[i].readOnly=FALSE;
		bzero(machine->mainMemory+j,PageSize);
	}
	k = memorymap->NumClear();
	return true;
}

void
MemoryManager::Release(int page,TranslationEntry *pageTable){
	int i;
	for(i=0;i<page;i++)
		memorymap->Clear(pageTable[i].physicalPage);
}