add cb_arg parameter to the _rte_eth_dev_callback_process function.
Adding a parameter to this function allows passing information
to the application when an eth device event occurs such as
a VF to PF message.
This allows the application to decide if a particular function
is permitted.
Signed-off-by: Bernard Iremonger <bernard.iremonger@intel.com>
Signed-off-by: Alex Zelezniak <alexz@att.com>
 
        vrtl_eth_dev->data->dev_link.link_status = link_status;
 
-       _rte_eth_dev_callback_process(vrtl_eth_dev, RTE_ETH_EVENT_INTR_LSC);
+       _rte_eth_dev_callback_process(vrtl_eth_dev, RTE_ETH_EVENT_INTR_LSC, NULL);
 }
 
 int
 
                return;
 
        _rte_eth_dev_callback_process((struct rte_eth_dev *)arg,
-                       RTE_ETH_EVENT_INTR_LSC);
+                       RTE_ETH_EVENT_INTR_LSC, NULL);
 }
 
 void
                                                (void *)bonded_eth_dev);
                        else
                                _rte_eth_dev_callback_process(bonded_eth_dev,
-                                               RTE_ETH_EVENT_INTR_LSC);
+                                               RTE_ETH_EVENT_INTR_LSC, NULL);
 
                } else {
                        if (internals->link_down_delay_ms > 0)
                                                (void *)bonded_eth_dev);
                        else
                                _rte_eth_dev_callback_process(bonded_eth_dev,
-                                               RTE_ETH_EVENT_INTR_LSC);
+                                               RTE_ETH_EVENT_INTR_LSC, NULL);
                }
        }
 }
 
 
        eth_em_interrupt_get_status(dev);
        eth_em_interrupt_action(dev);
-       _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC);
+       _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC, NULL);
 }
 
 static int
 
                E1000_WRITE_REG(hw, E1000_TCTL, tctl);
                E1000_WRITE_REG(hw, E1000_RCTL, rctl);
                E1000_WRITE_FLUSH(hw);
-               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC);
+               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC, NULL);
        }
 
        return 0;
 
        /* PF reset VF event */
        if (in_msg == E1000_PF_CONTROL_MSG)
-               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_RESET);
+               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_RESET, NULL);
 }
 
 static int
 
        vnic_intr_return_all_credits(&enic->intr);
 
        enic_link_update(enic);
-       _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC);
+       _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC, NULL);
        enic_log_q_error(enic);
 }
 
 
 
        /* handle the link up interrupt in an alarm callback */
        i40e_dev_link_update(dev, 0);
-       _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC);
+       _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC, NULL);
 
        i40e_pf_enable_irq0(hw);
        rte_intr_enable(&(dev->pci_dev->intr_handle));
                        return;
                else
                        _rte_eth_dev_callback_process(dev,
-                               RTE_ETH_EVENT_INTR_LSC);
+                               RTE_ETH_EVENT_INTR_LSC, NULL);
        }
 
 done:
 
        switch (pf_msg->event) {
        case I40E_VIRTCHNL_EVENT_RESET_IMPENDING:
                PMD_DRV_LOG(DEBUG, "VIRTCHNL_EVENT_RESET_IMPENDING event\n");
-               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_RESET);
+               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_RESET, NULL);
                break;
        case I40E_VIRTCHNL_EVENT_LINK_CHANGE:
                PMD_DRV_LOG(DEBUG, "VIRTCHNL_EVENT_LINK_CHANGE event\n");
 
                ixgbe_dev_link_update(dev, 0);
                intr->flags &= ~IXGBE_FLAG_NEED_LINK_UPDATE;
                ixgbe_dev_link_status_print(dev);
-               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC);
+               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC, NULL);
        }
 
        PMD_DRV_LOG(DEBUG, "enable intr in delayed handler S[%08x]", eicr);
 
        /* PF reset VF event */
        if (in_msg == IXGBE_PF_CONTROL_MSG)
-               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_RESET);
+               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_RESET, NULL);
 }
 
 static int
 
        ret = priv_dev_link_status_handler(priv, dev);
        priv_unlock(priv);
        if (ret)
-               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC);
+               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC, NULL);
 }
 
 /**
        ret = priv_dev_link_status_handler(priv, dev);
        priv_unlock(priv);
        if (ret)
-               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC);
+               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC, NULL);
 }
 
 /**
 
        ret = priv_dev_link_status_handler(priv, dev);
        priv_unlock(priv);
        if (ret)
-               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC);
+               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC, NULL);
 }
 
 /**
        ret = priv_dev_link_status_handler(priv, dev);
        priv_unlock(priv);
        if (ret)
-               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC);
+               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC, NULL);
 }
 
 /**
 
        struct rte_eth_dev *dev = (struct rte_eth_dev *)param;
 
        nfp_net_link_update(dev, 0);
-       _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC);
+       _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC, NULL);
 
        nfp_net_dev_link_status_print(dev);
 
 
        if (nicvf_reg_poll_interrupts(nic) == NIC_MBOX_MSG_BGX_LINK_CHANGE) {
                if (dev->data->dev_conf.intr_conf.lsc)
                        nicvf_set_eth_link_status(nic, &dev->data->dev_link);
-               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC);
+               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC, NULL);
        }
 
        rte_eal_alarm_set(NICVF_INTR_POLL_INTERVAL_MS * 1000,
 
 
        RTE_LOG(INFO, PMD, "New connection established\n");
 
-       _rte_eth_dev_callback_process(eth_dev, RTE_ETH_EVENT_INTR_LSC);
+       _rte_eth_dev_callback_process(eth_dev, RTE_ETH_EVENT_INTR_LSC, NULL);
 
        return 0;
 }
 
        RTE_LOG(INFO, PMD, "Connection closed\n");
 
-       _rte_eth_dev_callback_process(eth_dev, RTE_ETH_EVENT_INTR_LSC);
+       _rte_eth_dev_callback_process(eth_dev, RTE_ETH_EVENT_INTR_LSC, NULL);
 }
 
 static int
        RTE_LOG(INFO, PMD, "vring%u is %s\n",
                        vring, enable ? "enabled" : "disabled");
 
-       _rte_eth_dev_callback_process(eth_dev, RTE_ETH_EVENT_QUEUE_STATE);
+       _rte_eth_dev_callback_process(eth_dev, RTE_ETH_EVENT_QUEUE_STATE, NULL);
 
        return 0;
 }
 
        if (isr & VIRTIO_PCI_ISR_CONFIG) {
                if (virtio_dev_link_update(dev, 0) == 0)
                        _rte_eth_dev_callback_process(dev,
-                                                     RTE_ETH_EVENT_INTR_LSC);
+                                                     RTE_ETH_EVENT_INTR_LSC, NULL);
        }
 
 }
 
 
 void
 _rte_eth_dev_callback_process(struct rte_eth_dev *dev,
-       enum rte_eth_event_type event)
+       enum rte_eth_event_type event, void *cb_arg)
 {
        struct rte_eth_dev_callback *cb_lst;
        struct rte_eth_dev_callback dev_cb;
                        continue;
                dev_cb = *cb_lst;
                cb_lst->active = 1;
+               if (cb_arg != NULL)
+                       dev_cb.cb_arg = (void *) cb_arg;
+
                rte_spinlock_unlock(&rte_eth_dev_cb_lock);
                dev_cb.cb_fn(dev->data->port_id, dev_cb.event,
                                                dev_cb.cb_arg);
 
                                /**< queue state event (enabled/disabled) */
        RTE_ETH_EVENT_INTR_RESET,
                        /**< reset interrupt event, sent to VF on PF reset */
+       RTE_ETH_EVENT_VF_MBOX,  /**< message from the VF received by PF */
        RTE_ETH_EVENT_MAX       /**< max value of this enum */
 };
 
  * @param cb_arg
  *  Pointer to the parameters for the registered callback.
  *
+ *  The user data is overwritten in the case of RTE_ETH_EVENT_VF_MBOX.
+ *     This even occurs when a message from the VF is received by the PF.
+ *     The user data is overwritten with struct rte_pmd_ixgbe_mb_event_param.
+ *     This struct is defined in rte_pmd_ixgbe.h.
+ *
  * @return
  *  - On success, zero.
  *  - On failure, a negative value.
  *  Pointer to struct rte_eth_dev.
  * @param event
  *  Eth device interrupt event type.
+ * @param cb_arg
+ *  Update callback parameter to pass data back to user application.
+ *  This allows the user application to decide if a particular function
+ *  is permitted or not.
  *
  * @return
  *  void
  */
 void _rte_eth_dev_callback_process(struct rte_eth_dev *dev,
-                               enum rte_eth_event_type event);
+                               enum rte_eth_event_type event, void *cb_arg);
 
 /**
  * When there is no rx packet coming in Rx Queue for a long time, we can