i40e: Lock for VSI's MAC filter list

This patch introduces a spinlock which is to be used for synchronizing
access to VSI's MAC filter list.

This patch also synchronizes execution of other codepaths which are
accessing VSI's MAC filter list with execution of
service_task:sync_vsi_filters.

In function i40e_add_vsi, copied out LAA MAC address instead of cloning
MAC filter entry because only MAC address is needed to remove MAC VLAN
filter from FW/HW.

Change-ID: I0e10ac7c715d44aa994239642aa4d57c998573a2
Signed-off-by: Kiran Patil <kiran.patil@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40e/i40e.h

@@ -468,6 +468,8 @@ struct i40e_vsi {
 #define I40E_VSI_FLAG_VEB_OWNER		BIT(1)
 	unsigned long flags;
 
+	/* Per VSI lock to protect elements/list (MAC filter) */
+	spinlock_t mac_filter_list_lock;
 	struct list_head mac_filter_list;
 
 	/* VSI stats */

drivers/net/ethernet/intel/i40e/i40e_fcoe.c

@@ -1516,10 +1516,12 @@ void i40e_fcoe_config_netdev(struct net_device *netdev, struct i40e_vsi *vsi)
 	 * same PCI function.
 	 */
 	netdev->dev_port = 1;
+	spin_lock_bh(&vsi->mac_filter_list_lock);
 	i40e_add_filter(vsi, hw->mac.san_addr, 0, false, false);
 	i40e_add_filter(vsi, (u8[6]) FC_FCOE_FLOGI_MAC, 0, false, false);
 	i40e_add_filter(vsi, FIP_ALL_FCOE_MACS, 0, false, false);
 	i40e_add_filter(vsi, FIP_ALL_ENODE_MACS, 0, false, false);
+	spin_unlock_bh(&vsi->mac_filter_list_lock);
 
 	/* use san mac */
 	ether_addr_copy(netdev->dev_addr, hw->mac.san_addr);

drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c

@@ -547,6 +547,8 @@ static int i40e_alloc_vsi_res(struct i40e_vf *vf, enum i40e_vsi_type type)
 		 */
 		if (vf->port_vlan_id)
 			i40e_vsi_add_pvid(vsi, vf->port_vlan_id);
+
+		spin_lock_bh(&vsi->mac_filter_list_lock);
 		f = i40e_add_filter(vsi, vf->default_lan_addr.addr,
 				    vf->port_vlan_id ? vf->port_vlan_id : -1,
 				    true, false);
@@ -559,6 +561,7 @@ static int i40e_alloc_vsi_res(struct i40e_vf *vf, enum i40e_vsi_type type)
 		if (!f)
 			dev_info(&pf->pdev->dev,
 				 "Could not allocate VF broadcast filter\n");
+		spin_unlock_bh(&vsi->mac_filter_list_lock);
 	}
 
 	/* program mac filter */
@@ -1598,6 +1601,11 @@ static int i40e_vc_add_mac_addr_msg(struct i40e_vf *vf, u8 *msg, u16 msglen)
 	}
 	vsi = pf->vsi[vf->lan_vsi_idx];
 
+	/* Lock once, because all function inside for loop accesses VSI's
+	 * MAC filter list which needs to be protected using same lock.
+	 */
+	spin_lock_bh(&vsi->mac_filter_list_lock);
+
 	/* add new addresses to the list */
 	for (i = 0; i < al->num_elements; i++) {
 		struct i40e_mac_filter *f;
@@ -1616,9 +1624,11 @@ static int i40e_vc_add_mac_addr_msg(struct i40e_vf *vf, u8 *msg, u16 msglen)
 			dev_err(&pf->pdev->dev,
 				"Unable to add VF MAC filter\n");
 			ret = I40E_ERR_PARAM;
+			spin_unlock_bh(&vsi->mac_filter_list_lock);
 			goto error_param;
 		}
 	}
+	spin_unlock_bh(&vsi->mac_filter_list_lock);
 
 	/* program the updated filter list */
 	if (i40e_sync_vsi_filters(vsi, false))
@@ -1666,10 +1676,12 @@ static int i40e_vc_del_mac_addr_msg(struct i40e_vf *vf, u8 *msg, u16 msglen)
 	}
 	vsi = pf->vsi[vf->lan_vsi_idx];
 
+	spin_lock_bh(&vsi->mac_filter_list_lock);
 	/* delete addresses from the list */
 	for (i = 0; i < al->num_elements; i++)
 		i40e_del_filter(vsi, al->list[i].addr,
 				I40E_VLAN_ANY, true, false);
+	spin_unlock_bh(&vsi->mac_filter_list_lock);
 
 	/* program the updated filter list */
 	if (i40e_sync_vsi_filters(vsi, false))
@@ -2066,6 +2078,11 @@ int i40e_ndo_set_vf_mac(struct net_device *netdev, int vf_id, u8 *mac)
 		goto error_param;
 	}
 
+	/* Lock once because below invoked function add/del_filter requires
+	 * mac_filter_list_lock to be held
+	 */
+	spin_lock_bh(&vsi->mac_filter_list_lock);
+
 	/* delete the temporary mac address */
 	i40e_del_filter(vsi, vf->default_lan_addr.addr,
 			vf->port_vlan_id ? vf->port_vlan_id : -1,
@@ -2077,6 +2094,8 @@ int i40e_ndo_set_vf_mac(struct net_device *netdev, int vf_id, u8 *mac)
 	list_for_each_entry(f, &vsi->mac_filter_list, list)
 		i40e_del_filter(vsi, f->macaddr, f->vlan, true, false);
 
+	spin_unlock_bh(&vsi->mac_filter_list_lock);
+
 	dev_info(&pf->pdev->dev, "Setting MAC %pM on VF %d\n", mac, vf_id);
 	/* program mac filter */
 	if (i40e_sync_vsi_filters(vsi, false)) {
@@ -2109,6 +2128,7 @@ int i40e_ndo_set_vf_port_vlan(struct net_device *netdev,
 	u16 vlanprio = vlan_id | (qos << I40E_VLAN_PRIORITY_SHIFT);
 	struct i40e_netdev_priv *np = netdev_priv(netdev);
 	struct i40e_pf *pf = np->vsi->back;
+	bool is_vsi_in_vlan = false;
 	struct i40e_vsi *vsi;
 	struct i40e_vf *vf;
 	int ret = 0;
@@ -2138,7 +2158,11 @@ int i40e_ndo_set_vf_port_vlan(struct net_device *netdev,
 		/* duplicate request, so just return success */
 		goto error_pvid;
 
-	if (le16_to_cpu(vsi->info.pvid) == 0 && i40e_is_vsi_in_vlan(vsi)) {
+	spin_lock_bh(&vsi->mac_filter_list_lock);
+	is_vsi_in_vlan = i40e_is_vsi_in_vlan(vsi);
+	spin_unlock_bh(&vsi->mac_filter_list_lock);
+
+	if (le16_to_cpu(vsi->info.pvid) == 0 && is_vsi_in_vlan) {
 		dev_err(&pf->pdev->dev,
 			"VF %d has already configured VLAN filters and the administrator is requesting a port VLAN override.\nPlease unload and reload the VF driver for this change to take effect.\n",
 			vf_id);