How to find out whether a specific mounted Linux file system is located on a encrypted device?

Question

How can I find out via the command line whether a specific mounted file system in a Linux system is ultimately located on an encrypted device?

Of course, a generic solution would be nice, but basically I just need to deal with a file system on LVM and dm-crypt.

I don't need to consider encrypted file systems (e.g. ecryptfs) or TrueCrypt or anything else, or any other layers of indirection (e.g. dm-raid), but I definitely do need to cope with LVM, and I don't know the order, e.g. dm-crypt on LVM, or LVM on dm-crypt.