Provided by: librdmacm-dev_1.0.8-1_i386 bug

NAME

       rdma_accept - Called to accept a connection request.

SYNOPSIS

       #include <rdma/rdma_cma.h>

       int   rdma_accept   (struct   rdma_cm_id  *id,  struct  rdma_conn_param
       *conn_param);

ARGUMENTS

       id          Connection identifier associated with the request.

       conn_param  Information  needed  to  establish  the  connection.    See
                   CONNECTION PROPERTIES below for details.

DESCRIPTION

       Called  from  the  listening  side  to  accept a connection or datagram
       service lookup request.

NOTES

       Unlike the socket accept  routine,  rdma_accept  is  not  called  on  a
       listening  rdma_cm_id.   Instead,  after  calling rdma_listen, the user
       waits for an RDMA_CM_EVENT_CONNECT_REQUEST event to occur.   Connection
       request  events  give the user a newly created rdma_cm_id, similar to a
       new socket, but the rdma_cm_id is bound  to  a  specific  RDMA  device.
       rdma_accept is called on the new rdma_cm_id.

CONNECTION PROPERTIES

       The  following  properties  are used to configure the communication and
       specified by the conn_param parameter when accepting  a  connection  or
       datagram  communication  request.  Users should use the rdma_conn_param
       values  reported  in  the  connection  request   event   to   determine
       appropriate   values  for  these  fields  when  accepting.   Users  may
       reference  the  rdma_conn_param  structure  in  the  connection   event
       directly, or can reference their own structure.  If the rdma_conn_param
       structure from an event is referenced, the  event  must  not  be  acked
       until after this call returns.

       private_data
              References  a  user-controlled data buffer.  The contents of the
              buffer are copied and transparently passed to the remote side as
              part  of the communication request.  May be NULL if private_data
              is not required.

       private_data_len
              Specifies the size of the  user-controlled  data  buffer.   Note
              that the actual amount of data transferred to the remote side is
              transport dependent and may be larger than that requested.

       responder_resources
              The  maximum  number  of  outstanding  RDMA  read   and   atomic
              operations that the local side will accept from the remote side.
              Applies only to RDMA_PS_TCP.  This value must be  less  than  or
              equal  to the local RDMA device attribute max_qp_rd_atom and the
              responder_resources value reported in the connect request event.

       initiator_depth
              The   maximum   number  of  outstanding  RDMA  read  and  atomic
              operations that the local side will have  to  the  remote  side.
              Applies  only  to  RDMA_PS_TCP.  This value must be less than or
              equal to the local RDMA device attribute max_qp_init_rd_atom and
              the initiator_depth value reported in the connect request event.

       flow_control
              Specifies if hardware flow control is available.  This value  is
              exchanged  with the remote peer and is not used to configure the
              QP.  Applies only to RDMA_PS_TCP.

       retry_count
              This value is ignored.

       rnr_retry_count
              The maximum number of times  that  a  send  operation  from  the
              remote  peer should be retried on a connection after receiving a
              receiver not ready (RNR) error.  RNR errors are generated when a
              send  request arrives before a buffer has been posted to receive
              the incoming data.  Applies only to RDMA_PS_TCP.

       srq    Specifies if the QP associated with the connection  is  using  a
              shared receive queue.  This field is ignored by the library if a
              QP  has  been  created  on  the  rdma_cm_id.   Applies  only  to
              RDMA_PS_TCP.

       qp_num Specifies  the  QP  number associated with the connection.  This
              field is ignored by the library if a QP has been created on  the
              rdma_cm_id.

INFINIBAND SPECIFIC

       In  addition to the connection properties defined above, InfiniBand QPs
       are configured with minimum RNR NAK timer and local ACK timeout values.
       The  minimum  RNR  NAK  timer value is set to 0, for a delay of 655 ms.
       The local ACK timeout is calculated based on the  packet  lifetime  and
       local  HCA  ACK  delay.   The  packet  lifetime  is  determined  by the
       InfiniBand Subnet Administrator and is part of the route (path  record)
       information obtained by the active side of the connection.  The HCA ACK
       delay is a property of the locally used HCA.

       The RNR retry count is a 3-bit value.

SEE ALSO

       rdma_listen(3), rdma_reject(3), rdma_get_cm_event(3)