F2FS Preparing To Introduce New "Secure Erase" Functionality
F2FS_IOC_SEC_TRIM_FILE is a new ioctl for allowing secure TRIM/DISCARD erase of specific files. In case of DISCARD not being supported, zeroing out of the data range for the regular file is performed.
This interface is intended to be used as a "secure erase" feature for the file-system if wanting to securely wipe a file from disk. Of course, it will still be up to user-space for supporting and making use of the ioctl.
Wiring up of F2FS_IOC_SEC_TRIM_FILE is within the F2FS dev branch meaning it should arrive for Linux 5.9.