Wait for an IO to complete

Hi All, I want to wait in my code till the IO actually goes to the disk. For example struct buffer_head *bh=sb_bread(sb, 20) strcpy(bh->b_data, "Some Data"); /* mark and sync */ mark_buffer_dirty(bh); sync_dirty_buffer(bh); The above code only adds the bh to the request queue and returns. I need something write_buffer_to_disk(bh) Which will return only if the data has been written on disk. Please help -- Regards, Rishi Agrawal