嵌入式linux下获取flash分区大小

#include <stdio.h>                                                                                                                  
#include <stdlib.h>
#include <unistd.h>
#include <sys/vfs.h>
 
typedef unsigned long long u64;
 
//unit: 0-MBytes, 1-KBytes, default MBytes
int getPartitionUse(const char *dir, size_t &totleSize, size_t &freeSize, int unit)
{
    struct statfs diskInfo;  
    int ret = statfs(dir, &diskInfo);  
  if ( ret != 0 )
  {
    perror("getPartitionUse statfs error ");
    return ret;
  }
  
    u64 allBlocks = diskInfo.f_bsize;  
    u64 tmpTotalSize = allBlocks * diskInfo.f_blocks;  
    u64 tmpFreeDisk = diskInfo.f_bfree*allBlocks;  
    totleSize = tmpTotalSize>>20;  
  freeSize  = tmpFreeDisk>>20;
  
  if(unit == 0)
  {  
    totleSize  = tmpTotalSize>>20;  
    freeSize  = tmpFreeDisk>>20;  
  }
  else if( unit == 1 )
  {
    totleSize  = tmpTotalSize>>10;  
    freeSize  = tmpFreeDisk>>10; 
  }
  
  return 0;
}
 
int main()
{
  size_t totleSize = 0;
  size_t freeSize = 0;
  
    getPartitionUse("/", totleSize,freeSize, 0);
    printf ("system  total=%dMB, free=%dMB\n", totleSize, freeSize);  
 
    getPartitionUse("/work/data", totleSize,freeSize, 0);
    printf ("data  total=%dMB, free=%dMB\n", totleSize, freeSize);  
  
    getPartitionUse("/work", totleSize,freeSize, 0);
    printf ("config  total=%dMB, free=%dMB\n", totleSize, freeSize);  


}