igb: fix recent VLAN changes that would leave VLANs disabled after reset

This patch cleans up several issues with VLANs on igb after the recent
changes that were meant to leave the VLANs enabled/disable via the
netdev->features flags.

Specifically the Rx VLAN settings were being dropped after reset due to the
fact that they were not being restored correctly.  In addition I removed
the IRQ disable/enable since those were in place to protect the setting of
vlgrp.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Aaron Brown  <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/igb/igb_main.c

@@ -2112,8 +2112,6 @@ static int __devinit igb_probe(struct pci_dev *pdev,
 	if (err)
 		goto err_register;
 
-	igb_vlan_mode(netdev, netdev->features);
-
 	/* carrier off reporting is important to ethtool even BEFORE open */
 	netif_carrier_off(netdev);
 
@@ -5120,7 +5118,6 @@ static s32 igb_vlvf_set(struct igb_adapter *adapter, u32 vid, bool add, u32 vf)
 			}
 
 			adapter->vf_data[vf].vlans_enabled++;
-			return 0;
 		}
 	} else {
 		if (i < E1000_VLVF_ARRAY_SIZE) {
@@ -6385,10 +6382,9 @@ static void igb_vlan_mode(struct net_device *netdev, u32 features)
 	struct igb_adapter *adapter = netdev_priv(netdev);
 	struct e1000_hw *hw = &adapter->hw;
 	u32 ctrl, rctl;
+	bool enable = !!(features & NETIF_F_HW_VLAN_RX);
 
-	igb_irq_disable(adapter);
-
-	if (features & NETIF_F_HW_VLAN_RX) {
+	if (enable) {
 		/* enable VLAN tag insert/strip */
 		ctrl = rd32(E1000_CTRL);
 		ctrl |= E1000_CTRL_VME;
@@ -6406,9 +6402,6 @@ static void igb_vlan_mode(struct net_device *netdev, u32 features)
 	}
 
 	igb_rlpml_set(adapter);
-
-	if (!test_bit(__IGB_DOWN, &adapter->state))
-		igb_irq_enable(adapter);
 }
 
 static void igb_vlan_rx_add_vid(struct net_device *netdev, u16 vid)
@@ -6433,11 +6426,6 @@ static void igb_vlan_rx_kill_vid(struct net_device *netdev, u16 vid)
 	int pf_id = adapter->vfs_allocated_count;
 	s32 err;
 
-	igb_irq_disable(adapter);
-
-	if (!test_bit(__IGB_DOWN, &adapter->state))
-		igb_irq_enable(adapter);
-
 	/* remove vlan from VLVF table array */
 	err = igb_vlvf_set(adapter, vid, false, pf_id);
 
@@ -6452,6 +6440,8 @@ static void igb_restore_vlan(struct igb_adapter *adapter)
 {
 	u16 vid;
 
+	igb_vlan_mode(adapter->netdev, adapter->netdev->features);
+
 	for_each_set_bit(vid, adapter->active_vlans, VLAN_N_VID)
 		igb_vlan_rx_add_vid(adapter->netdev, vid);
 }