3.1.4.4 Deregister Buffer
When the upper layer has completed operations which require remote access to a previously registered local buffer as the source or destination of a peer RDMA Read or RDMA Write operation, it passes:
The implementation-defined representation of the Connection.
One or more Buffer Descriptor V1 structures as returned from prior calls to Register Buffer.
The registration MUST use implementation-specific means to deregister each memory region indicated by each Buffer Descriptor V1 structure with the underlying RDMA provider. If the RDMA provider indicates an error for any deregistration, the error result MUST be provided to the upper layer. Otherwise, it MUST be ensured, in an implementation-specific manner via the RDMA lower layer provider, that all remote access to the specified buffers is complete and that no further remote access is possible.