qla3xxx: Ensure request/response queue addr writes to the registers

Before use the request and response queue addr, make sure it has wrote
to the registers.

Signed-off-by: Joe Jin <joe.jin@oracle.com>
Cc: Jitendra Kalsaria <jitendra.kalsaria@qlogic.com>
Cc: Ron Mercer <ron.mercer@qlogic.com>
Acked-by: Jitendra Kalsaria <jitendra.kalsaria@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/qlogic/qla3xxx.c b/drivers/net/ethernet/qlogic/qla3xxx.c
index df09b1c..6407d0d 100644
--- a/drivers/net/ethernet/qlogic/qla3xxx.c
+++ b/drivers/net/ethernet/qlogic/qla3xxx.c
@@ -2525,6 +2525,13 @@
 	qdev->req_q_size =
 	    (u32) (NUM_REQ_Q_ENTRIES * sizeof(struct ob_mac_iocb_req));
 
+	qdev->rsp_q_size = NUM_RSP_Q_ENTRIES * sizeof(struct net_rsp_iocb);
+
+	/* The barrier is required to ensure request and response queue
+	 * addr writes to the registers.
+	 */
+	wmb();
+
 	qdev->req_q_virt_addr =
 	    pci_alloc_consistent(qdev->pdev,
 				 (size_t) qdev->req_q_size,
@@ -2536,8 +2543,6 @@
 		return -ENOMEM;
 	}
 
-	qdev->rsp_q_size = NUM_RSP_Q_ENTRIES * sizeof(struct net_rsp_iocb);
-
 	qdev->rsp_q_virt_addr =
 	    pci_alloc_consistent(qdev->pdev,
 				 (size_t) qdev->rsp_q_size,