Tribblix: manual page: dat_ep_dup

DAT_EP_DUP_CONNECT(3DAT) Direct Access Transport Library Functions

NAME

dat_ep_dup_connect - establish a connection between the local
Endpoint and a remote Endpoint

SYNOPSIS

cc [ flag... ] file... -ldat [ library... ]
#include <dat/udat.h>

DAT_RETURN
dat_ep_dup_connect (
IN DAT_EP_HANDLE ep_handle,
IN DAT_EP_HANDLE dup_ep_handle,
IN DAT_TIMEOUT timeout,
IN DAT_COUNT private_data_size,
IN const DAT_PVOID private_data,
IN DAT_QOS qos
)

PARAMETERS

ep_handle
Handle for an instance of an Endpoint.

dup_ep_handle
Connected local Endpoint that specifies a
requested connection remote end.

timeout:
Duration of time, in microseconds, that
Consumers wait for Connection establishment. The
value of DAT_TIMEOUT_INFINITE represents no
timeout, indefinite wait. Values must be
positive.

private_data_size
Size of private_data. Must be nonnegative.

private_data
Pointer to the private data that should be
provided to the remote Consumer as part of the
Connection Request. If private_data_size is
zero, then private_data can be NULL.

qos
Requested Quality of Service of the connection.

DESCRIPTION

The dat_ep_dup_connect() function requests that a connection be
established between the local Endpoint and a remote Endpoint. This
operation is used by the active/client side Consumer of the
connection model. The remote Endpoint is identified by the
dup_ep_handle. The remote end of the requested connection shall be
the same as the remote end of the dup_ep_handle. This is equivalent
to requesting a connection to the same remote IA, Connection
Qualifier, and connect_flags as used for establishing the connection
on duplicated Endpoints and following the same redirections.

Upon establishing the requested connection as part of the successful
completion of this operation, the local Endpoint is bound to a Port
Qualifier of the local IA. The Port Qualifier is passed to the remote
side of the requested connection and is available to the remote
Consumer in the Connection Request of the
DAT_CONNECTION_REQUEST_EVENT.

The Consumer-provided private_data is passed to the remote side and
is provided to the remote Consumer in the Connection Request.
Consumers can encapsulate any local Endpoint attributes that remote
Consumers need to know as part of an upper-level protocol. Providers
can also provide a Provider on the remote side any local Endpoint
attributes and Transport-specific information needed for Connection
establishment by the Transport.

Upon successful completion of this operation, the local Endpoint is
transferred into DAT_EP_STATE_ACTIVE_CONNECTION_PENDING.

Consumers can request a specific value of qos. The Provider specifies
which Quality of Service it supports in documentation and in the
Provider attributes. If the local Provider or Transport does not
support the requested qos, the operation fails and
DAT_MODEL_NOT_SUPPORTED is returned synchronously. If the remote
Provider does not support the requested qos, the local Endpoint is
automatically transitioned into a DAT_EP_STATE_UNDISCONNECTED state,
the connection is not established, and the event returned on the
connect_evd_handle is DAT_CONNECTION_EVENT_NON_PEER_REJECTED. The
same DAT_CONNECTION_EVENT_NON_PEER_REJECTED event is returned if
connection cannot be established for all reasons for not establishing
the connection, except timeout, remote host not reachable, and remote
peer reject. For example, remote host is not reachable, remote
Consumer is not listening on the requested Connection Qualifier,
Backlog of the requested Service Point is full, and Transport errors.
In this case, the local Endpoint is automatically transitioned into a
DAT_EP_STATE_UNDISCONNECTED state.

The acceptance of the requested connection by the remote Consumer is
reported to the local Consumer through a
DAT_CONNECTION_EVENT_ESTABLISHED event on the connect_evd_handle of
the local Endpoint.

The rejection of the connection by the remote Consumer is reported to
the local Consumer through a DAT_CONNECTION_EVENT_PEER_REJECTED event
on the connect_evd_handle of the local Endpoint and the local
Endpoint is automatically transitioned into a
DAT_EP_STATE_UNDISCONNECTED state.

When the Provider cannot reach the remote host or the remote host
does not respond within the Consumer-requested timeout, a
DAT_CONNECTION_EVENT_UNREACHABLE is generated on the
connect_evd_handle of the Endpoint. The Endpoint transitions into a
DAT_EP_STATE_DISCONNECTED state.

The local Endpoint is automatically transitioned into a
DAT_EP_STATE_CONNECTED state when a Connection Request is accepted by
the remote Consumer and the Provider completes the Transport-specific
Connection establishment. The local Consumer is notified of the
established connection through a DAT_CONNECTION_EVENT_ESTABLISHED
event on the connect_evd_handle of the local Endpoint.

When the timeout expired prior to completion of the Connection
establishment, the local Endpoint is automatically transitioned into
a DAT_EP_STATE_UNDISCONNECTED state and the local Consumer through a
DAT_CONNECTION_EVENT_TIMED_OUT event on the connect_evd_handle of the
local Endpoint.

RETURN VALUES

DAT_SUCCESS
The operation was successful.

DAT_INSUFFICIENT_RESOURCES
The operation failed due to resource
limitations.

DAT_INVALID_PARAMETER
Invalid parameter.

DAT_INVALID_HANDLE
The ep_handle or dup_ep_handle
parameter is invalid.

DAT_INVALID_STATE
A parameter is in an invalid state.

DAT_MODEL_NOT_SUPPORTED
The requested Model is not supported by
the Provider. For example, requested
qos was not supported by the local
Provider.

USAGE

It is up to the Consumer to negotiate outstanding RDMA Read incoming
and outgoing with a remote peer. The outstanding RDMA Read outgoing
attribute should be smaller than the remote Endpoint outstanding RDMA
Read incoming attribute. If this is not the case, connection
establishment might fail.

DAT API does not define a protocol on how remote peers exchange
Endpoint attributes. The exchange of outstanding RDMA Read incoming
and outgoing attributes of EPs is left to the Consumer ULP. The
Consumer can use Private Data for it.

If the Consumer does not care about posting RDMA Read operations or
remote RDMA Read operations on the connection, it can set the two
outstanding RDMA Read attribute values to 0.

If the Consumer does not set the two outstanding RDMA Read attributes
of the Endpoint, the Provider is free to pick up any values as a
default. The Provider is allowed to change these default values
during connection setup.

ATTRIBUTES