drivers/block/rd.c under 2.2.16

I am attempting to get something figured out dealing with the ramdisk
under Linux 2.2.16.  I am trying to figure out whether you can use the
ramdisk to act as a RAM filesystem doing normal file creations and
deletion.  I noticed that within the code it makes comments about not
having to free stuff up.  Does that mean you can't delete things off the
ramdisk filesystem?  I have created a ramdisk, formatted ext2, and mounted
it.  When I create stuff on there, and then I delete it, I notice that if
I do a df, the size doesn't go back down after I have deleted the file.  
I am trying to figure out if that is how it was intended to happen, or
whether I have just done something not quite correctly and you can't
really use it as a RAM file system.

Thanks,
Matthew M. Copeland