FS Encryption (Per-file encryption)

modulename: fscrypto.ko


Linux Kernel Configuration
└─>File systems
└─>FS Encryption (Per-file encryption)
In linux kernel since version 3.10 (release Date: 2013-06-30)  
Enable encryption of files and directories. This
feature is similar to ecryptfs, but it is more memory
efficient since it avoids caching the encrypted and
decrypted pages in the page cache. Currently Ext4,
F2FS and UBIFS make use of this feature.

source code: