As this apparently got merged despite no proper reviews from VFS level persons: NAK - the ioctl format that expects the verifycation hash in the file data data with padding after the real data is simply not acceptable, we can't just transform the data in the file itself based on a magic calls like this. Also the core code should not depend on this as a storage format, which is a rather bad idea. In any modern file system you can store data like this out of line in something like the attr fork in XFS, or the attr items in btrfs.
