NAME

       rdma_create_id - Allocate a communication identifier.

SYNOPSIS

       #include <rdma/rdma_cma.h>

       int  rdma_create_id  (struct  rdma_event_channel  *channel,  struct  rdma_cm_id **id, void
       *context, enum rdma_port_space ps);

ARGUMENTS

       channel     The communication channel that events associated with the allocated rdma_cm_id
                   will be reported on.  This may be NULL.

       id          A reference where the allocated communication identifier will be returned.

       context     User specified context associated with the rdma_cm_id.

       ps          RDMA port space.

DESCRIPTION

       Creates an identifier that is used to track communication information.

RETURN VALUE

       Returns  0  on success, or -1 on error.  If an error occurs, errno will be set to indicate
       the failure reason.

NOTES

       Rdma_cm_id's are  conceptually  equivalent  to  a  socket  for  RDMA  communication.   The
       difference  is  that  RDMA  communication  requires explicitly binding to a specified RDMA
       device before communication can occur, and most operations  are  asynchronous  in  nature.
       Asynchronous  communication  events  on  an rdma_cm_id are reported through the associated
       event channel.  If the channel parameter is NULL,  the  rdma_cm_id  will  be  placed  into
       synchronous  operation.  While operating synchronously, calls that result in an event will
       block until the operation completes.  The event will be returned to the user  through  the
       rdma_cm_id structure, and be available for access until another rdma_cm call is made.

       Users must release the rdma_cm_id by calling rdma_destroy_id.

PORT SPACE

       Details of the services provided by the different port spaces are outlined below.

       RDMA_PS_TCP
              Provides reliable, connection-oriented QP communication.  Unlike TCP, the RDMA port
              space provides message, not stream, based communication.

       RDMA_PS_UDP
              Provides unreliable, connectionless QP communication.  Supports both  datagram  and
              multicast communication.

       RDMA_PS_IB
              Provides for any IB services (UD, UC, RC, XRC, etc.).

SEE ALSO

       rdma_cm(7),    rdma_create_event_channel(3),    rdma_destroy_id(3),   rdma_get_devices(3),
       rdma_bind_addr(3),      rdma_resolve_addr(3),       rdma_connect(3),       rdma_listen(3),
       rdma_set_option(3)