cxgb4: add Tx and Rx path for ETHOFLD traffic

Implement Tx path for traffic flowing through software EOSW_TXQ
and EOHW_TXQ. Since multiple EOSW_TXQ can post packets to a single
EOHW_TXQ, protect the hardware queue with necessary spinlock. Also,
move common code used to generate TSO work request to a common
function.

Implement Rx path to handle Tx completions for successfully
transmitted packets.

Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/chelsio/cxgb4/cxgb4.h

@@ -805,6 +805,7 @@ struct sge_uld_txq_info {
 
 enum sge_eosw_state {
 	CXGB4_EO_STATE_CLOSED = 0, /* Not ready to accept traffic */
+	CXGB4_EO_STATE_ACTIVE, /* Ready to accept traffic */
 };
 
 struct sge_eosw_desc {
@@ -1951,6 +1952,8 @@ void free_tx_desc(struct adapter *adap, struct sge_txq *q,
 void cxgb4_eosw_txq_free_desc(struct adapter *adap, struct sge_eosw_txq *txq,
 			      u32 ndesc);
 void cxgb4_ethofld_restart(unsigned long data);
+int cxgb4_ethofld_rx_handler(struct sge_rspq *q, const __be64 *rsp,
+			     const struct pkt_gl *si);
 void free_txq(struct adapter *adap, struct sge_txq *q);
 void cxgb4_reclaim_completed_tx(struct adapter *adap,
 				struct sge_txq *q, bool unmap);

drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_mqprio.c

@@ -174,7 +174,8 @@ static int cxgb4_mqprio_alloc_hw_resources(struct net_device *dev)
 		eorxq->fl.size = CXGB4_EOHW_FLQ_DEFAULT_DESC_NUM;
 
 		ret = t4_sge_alloc_rxq(adap, &eorxq->rspq, false,
-				       dev, msix, &eorxq->fl, NULL,
+				       dev, msix, &eorxq->fl,
+				       cxgb4_ethofld_rx_handler,
 				       NULL, 0);
 		if (ret)
 			goto out_free_queues;