Defined in github.com/aws/aws-sdk-go/service/ec2/api.go
The block device mapping.
Supplying both a snapshot ID and an encryption value as arguments for block-device
mapping results in an error. This is because only blank volumes can be encrypted on start, and these are not created from a snapshot. If a snapshot is the basis for the volume, it contains data by definition and its encryption status cannot be changed using this action.