Encryption Support For EXT4
Ted published the twenty-two patches earlier this month for implementing encryption support into EXT4, complete with file-name and symlink encryption. The patches were developed by Ted Ts'o and Michael Halcrow.
There's just over three-thousand new lines of code in the kernel for implementing this encryption support. The design and implementation might end up getting shared too with the new F2FS Flash-Friendly File-System.
The patch series with more information on the EXT4 encryption support can be found via the EXT4 mailing list.