vmxnet3: Register shutdown handler for device (fwd)

Implement a handler for pci shutdown so that the driver has an
opportunity to make sure that device is quiesced before the PCI
switches to legacy IRQs. This way the possibility of
"screaming interrupt" is avoided.
Acked-by: Shrikrishna Khare <skhare@vmware.com>
Signed-off-by: Shreyas N Bhatewara <sbhatewara@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/vmxnet3/vmxnet3_drv.c

@@ -3184,6 +3184,32 @@ vmxnet3_remove_device(struct pci_dev *pdev)
 	free_netdev(netdev);
 }
 
+static void vmxnet3_shutdown_device(struct pci_dev *pdev)
+{
+	struct net_device *netdev = pci_get_drvdata(pdev);
+	struct vmxnet3_adapter *adapter = netdev_priv(netdev);
+	unsigned long flags;
+
+	/* Reset_work may be in the middle of resetting the device, wait for its
+	 * completion.
+	 */
+	while (test_and_set_bit(VMXNET3_STATE_BIT_RESETTING, &adapter->state))
+		msleep(1);
+
+	if (test_and_set_bit(VMXNET3_STATE_BIT_QUIESCED,
+			     &adapter->state)) {
+		clear_bit(VMXNET3_STATE_BIT_RESETTING, &adapter->state);
+		return;
+	}
+	spin_lock_irqsave(&adapter->cmd_lock, flags);
+	VMXNET3_WRITE_BAR1_REG(adapter, VMXNET3_REG_CMD,
+			       VMXNET3_CMD_QUIESCE_DEV);
+	spin_unlock_irqrestore(&adapter->cmd_lock, flags);
+	vmxnet3_disable_all_intrs(adapter);
+
+	clear_bit(VMXNET3_STATE_BIT_RESETTING, &adapter->state);
+}
+
 
 #ifdef CONFIG_PM
 
@@ -3360,6 +3386,7 @@ static struct pci_driver vmxnet3_driver = {
 	.id_table	= vmxnet3_pciid_table,
 	.probe		= vmxnet3_probe_device,
 	.remove		= vmxnet3_remove_device,
+	.shutdown	= vmxnet3_shutdown_device,
 #ifdef CONFIG_PM
 	.driver.pm	= &vmxnet3_pm_ops,
 #endif