code: def _parse_array_bitmap(self, block):
          
          array_bitmap_regexp = re.compile(
              '^ *bitmap: (?P<allocated_pages>[0-9]*)/'
              '(?P<total_pages>[0-9]*) pages '
              '\[(?P<page_size>[0-9]*)KB\], '
              '(?P<chunk_size>[0-9]*)KB chunk.*$',
              re.MULTILINE
          )
  
          regexp_res = array_bitmap_regexp.search(block)
  
          # bitmap is optionally in mdstat
          if not regexp_res:
              return None
  
          array_bitmap_dict = regexp_res.groupdict()
          array_bitmap_dict_sanitizied = {}
  
          # convert all values to int
          for key, value in array_bitmap_dict.iteritems():
                  if not value:
                      continue
                  array_bitmap_dict_sanitizied[key] = int(value)
  
          # convert page_size to bytes
          array_bitmap_dict_sanitizied['page_size'] *= 1024
  
          # convert chunk_size to bytes
          array_bitmap_dict_sanitizied['chunk_size'] *= 1024
  
          return array_bitmap_dict
docs: Parse the bitmap status of the md array.
  
          >>> block = 'md0 : active raid1 sdd2[0] sdb2[2](S) sdc2[1]\n'
          >>>         '      100171776 blocks super 1.2 [2/2] [UU]\n'
          >>>         '      bitmap: 1/1 pages [4KB], 65536KB chunk\n\n'
          >>> print _parse_array_bitmap(block)
          {
              'total_pages': '1',
              'allocated_pages': '1',
              'page_size': 4096,
              'chunk_size': 67108864
          }
  
          :return: dictionary of bitmap status information
          :rtype: dict