RDMA Features

IND2ProviderControl Interface

Instantiating a NetworkDirect Provider Control

To use the new API call, the library's DllGetClassObject entry point must instantiate the IND2ProviderControl interface, using the IID_IND2ProviderControl iid.

Example:Disabling Mellanox Device while NetworkDirect Applications are Running

            

            
AutoRef<IClassFactory> aClassFactory;
//…..//
AutoRef<IND2ProviderControl> aProviderControl;
hr = aClassFactory->CreateInstance(NULL, IID_IND2ProviderControl, (void**)&aProvider-Control);
RETURN_IF_FAILED(hr);
        

ND2RegisterForAdapterStatus

Once an IND2ProviderControl instance is instantiated, the following function can be called to register an adapter into the provider status mechanism:

Syntax:

            

            
HRESULT
Nd2RegisterForAdapterStatus(
__in IND2ProviderControl* pCtrl,
__in IND2_FN_ADAPTER_STATUS* pfnCallback,
__in void* pvContext,
__in_bcount(cbAddress) const struct sockaddr* pAddress,
__in ULONG cbAddress,
__deref_out void** ppHandle
)
        

Parameters:

The IND2ProviderControl instance is created by the IClassFactory::CreateInstance function.

• IND2ProviderControl [in]: The function callback that is called once a status change is detected for the specific adapter, detailed for the function parameters.

• pvContext [in]: A context value to associate with the registered adapter.

• pAddress [in]: A sockaddr buffer that specifies the local address to use for the shared endpoint. Typically, this is a sockaddr_in structure for IPv4 addresses and a sockaddr_in6 structure for IPv6 addresses.
  If the sin_port or sin6_port member is specified as zero, the provider assigns a unique port number to the application from the ephemeral port range.

• cbAddress [in]: The size, in bytes, of the pAddress buffer.

• ppHandle [out]: The handle of the registered adapter. This parameter must be called with Nd2DeregisterForAdapterStatus before the final release of the Nd2RegisterForAdapterStatus instance.

Return value:

IND2_FN_ADAPTER_STATUS

The following is the function callback signature that must be provided to the Nd2RegisterForAdapterStatus function to be called upon an adapter status change:

Syntax:

            

            
void CALLBACK IND2_FN_ADAPTER_STATUS(
__in void* pvContext,
__in_bcount(cbAddress) const struct sockaddr* pAddress,
__in ULONG cbAddress,
__in DWORD dwStatusFlags
);
        

Parameters:

• pvContext [in]: A context value to associate with the registered adapter.

• pAddress [in]: A sockaddr buffer that specifies the local address to use for the shared endpoint. Typically, this is a sockaddr_in structure for IPv4 addresses and a sockaddr_in6 structure for IPv6 addresses.
  If the sin_port or sin6_port member is specified as zero, the provider assigns a unique port number to the application from the ephemeral port range.

• cbAddress [in]: The size, in bytes, of the pAddress buffer.

• dwStatusFlags [in]: The state flag of the new adapter status. Could be a single state flag or a combination of the following:

New Adapter Status State Flag Return Value:

Nd2DeregisterForAdapterStatus

The Nd2DeregisterForAdapterStatus function must be called to deregister a registered adapter from the IND2ProviderControl. Failing to call the function will result in unreleased allocated memory.

Syntax:

            

            
HRESULT
Nd2DeregisterForAdapterStatus(
__in IND2ProviderControl* pCtrl,
__in void* pHandle
)
        

Parameters:

• IND2ProviderControl [in]: The IND2ProviderControl created by the IClassFactory::CreateInstance function.

• pHandle [in]: The handle of the deregistered adapter.

Return value:

Sample Code - Register:

            

            
static void CALLBACK
OnAdapterStatus(
__in void* pvContext,
__in_bcount(cbAddress) const struct sockaddr* pAddress,
__in ULONG cbAddress,
__in DWORD dwStatusFlags
){
  //….. //
  printf("flags = %x\n", dwStatusFlags); //Print the new adapter status
}
 
 
AutoRef<INetworkAddressInfo> aAddressInfo; // INetworkAddressInfo Object
//….
//CreateNetworkAddressInfo with aAddressInfo
//….
DWORD aContext; //Context for the specific adapter being registerd
void* pvNd2RegisterForAdapterStatus = NULL; //AdapterStatus
 
 
hr = Nd2RegisterForAdapterStatus(
     aProviderControl,
     OnAdapterStatus,
     &aContext,
     aAddressInfo->GetAddr(),
     aAddressInfo->Length(),
     & pvNd2RegisterForAdapterStatus);
  RETURN_IF_FAILED(hr);
//………………………………………………………………………….//
//………………………………………………………………………………….//
   if (pvNd2RegisterForAdapterStatus) {
     hr = Nd2DeregisterForAdapterStatus(aProviderControl, pvNd2RegisterForAdapter-
Status);
  }
return hr;
        

Mellanox’s NIC device can be disabled at any time. When the device is disabled while NetworkDirect (ND) applications are running, the following will occur:

• Any new request or operation that is executed by the ND application will fail explicitly

• All pending overlapped requests will be canceled

• All pending send requests will be completed with error (flush with error)

• All RDMA resources will be released

• The device will be marked as disabled