ixgbevf: Take action when the PF notifies the VF it is resetting.

When the VF driver gets a control message from the PF that indicates the
PF is about to reset or go down we schedule the watchdog timer so that
it will detect the PF has gone offline and take appropriate action.
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ixgbevf/ixgbevf_main.c

@@ -956,10 +956,17 @@ static irqreturn_t ixgbevf_msix_mbx(int irq, void *data)
 	struct ixgbevf_adapter *adapter = netdev_priv(netdev);
 	struct ixgbe_hw *hw = &adapter->hw;
 	u32 eicr;
+	u32 msg;
 
 	eicr = IXGBE_READ_REG(hw, IXGBE_VTEICS);
 	IXGBE_WRITE_REG(hw, IXGBE_VTEICR, eicr);
 
+	hw->mbx.ops.read(hw, &msg, 1);
+
+	if ((msg & IXGBE_MBVFICR_VFREQ_MASK) == IXGBE_PF_CONTROL_MSG)
+		mod_timer(&adapter->watchdog_timer,
+			  round_jiffies(jiffies + 10));
+
 	return IRQ_HANDLED;
 }