將邏輯地址轉換爲頁碼和索引

我應該將logicalAddress轉換爲pageNumber和索引，但我不知道如何執行此操作。 logicalAddress是一個五位數的整數（邏輯地址以十進制表示）。任何提示？將邏輯地址轉換爲頁碼和索引

public byte read(int logicalAddress){ 
    //called by a process to read memory from its logical address 
    //this.pageNumber = pageNumber; 
    byte data=0; 

    //THIS IS THE PART I NEED HELP WITH ******* 

    //calculate pageNumber and index from the logical address 
    int pageNumber = (logicalAddress/NbrOfPages); 
    int index = (logicalAddress-(pageNumber*PageSize)); 

    //***************************************** 

    //check if we get a pageFault 
    if(pageTable[pageNumber]==-1){ 
     //call method to solve page fault 
     pageFault(pageNumber); 
     //the following two should be used in step 2 and 3 of the lab 
     //pageFaultFIFO(pageNumber); 
     //pageFaultLRU(pageNumber); 
    } 
    //read data from RAM 
    int frame=pageTable[pageNumber]; 
    int physicalAddress=frame*PageSize+index; 
    data=RAM[physicalAddress]; 
    //print result 
    System.out.print("Virtual address: "+logicalAddress); 
    System.out.print(" Physical address: "+physicalAddress); 
    System.out.println(" Value: "+data); 
    return data; 
}

來源

2014-10-09 user3415034

假設這是一個大約x64（英特爾），有你的英特爾CPU手冊。 – 2014-10-09 15:51:54

這是一個模擬尋呼，虛擬內存。 – user3415034 2014-10-09 15:52:59

您需要以頁面表大小爲單位開始。從您需要打破地址分爲兩個字段（偏移頁表索引和字節）：

unsigned long long MASK = PAGESIZE-1 ;

的頁表索引然後

unsigned long long index = (address & ~MASK)/PAGESIZE ;

，而偏移

unsigned long long offset = address & mask ;

或者：

unsigned long long index = address/PAGESIZE ; 
unsigned long long offset = address % PAGESIZE ;

來源

2014-10-27 00:36:48 user3344003

將邏輯地址轉換爲頁碼和索引

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