After performing a clean install of Yosemite (erasing the entire disk using disk utility during installation), the original name of the disk (APPLE HDD HTS547575A9E384 Media) turned out to be "Macintosh HD" eventually. In addition, there are only two actions left, first aid and partition.
I have carried out clean installs several times on this MacBook Pro (13-inch, mid 2012, now running 10.10.4), but this is the first time that I encounter this kind of problem. The only thing I did was erase the entire disk. Hope to return back to its original state, showing its real name and available actions.