bnx2x: Prevent inner-reload while VFs exist

On some feature changes, driver employes an inner-reload flow where it
resets the function and re-configures it with the new required set of
parameters.

Such a flow proves fatal to any VF since those were not intended to be used
while HW is being reset underneath, causing them [at best] to lose all
connectivity.

This changes driver behavior to fail all configuration changes [e.g., mtu
change] requested of the driver in case VFs are active.
Signed-off-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: Ariel Elior <Ariel.Elior@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c

@@ -4809,6 +4809,23 @@ netdev_features_t bnx2x_fix_features(struct net_device *dev,
 {
 	struct bnx2x *bp = netdev_priv(dev);
 
+	if (pci_num_vf(bp->pdev)) {
+		netdev_features_t changed = dev->features ^ features;
+
+		/* Revert the requested changes in features if they
+		 * would require internal reload of PF in bnx2x_set_features().
+		 */
+		if (!(features & NETIF_F_RXCSUM) && !bp->disable_tpa) {
+			features &= ~NETIF_F_RXCSUM;
+			features |= dev->features & NETIF_F_RXCSUM;
+		}
+
+		if (changed & NETIF_F_LOOPBACK) {
+			features &= ~NETIF_F_LOOPBACK;
+			features |= dev->features & NETIF_F_LOOPBACK;
+		}
+	}
+
 	/* TPA requires Rx CSUM offloading */
 	if (!(features & NETIF_F_RXCSUM)) {
 		features &= ~NETIF_F_LRO;
@@ -4839,6 +4856,8 @@ int bnx2x_set_features(struct net_device *dev, netdev_features_t features)
 	else
 		flags &= ~GRO_ENABLE_FLAG;
 
+	/* VFs or non SRIOV PFs should be able to change loopback feature */
+	if (!pci_num_vf(bp->pdev)) {
 		if (features & NETIF_F_LOOPBACK) {
 			if (bp->link_params.loopback_mode != LOOPBACK_BMAC) {
 				bp->link_params.loopback_mode = LOOPBACK_BMAC;
@@ -4850,6 +4869,7 @@ int bnx2x_set_features(struct net_device *dev, netdev_features_t features)
 				bnx2x_reload = true;
 			}
 		}
+	}
 
 	changes = flags ^ bp->flags;
 
@@ -4931,6 +4951,11 @@ int bnx2x_resume(struct pci_dev *pdev)
 	}
 	bp = netdev_priv(dev);
 
+	if (pci_num_vf(bp->pdev)) {
+		DP(BNX2X_MSG_IOV, "VFs are enabled, can not change MTU\n");
+		return -EPERM;
+	}
+
 	if (bp->recovery_state != BNX2X_RECOVERY_DONE) {
 		BNX2X_ERR("Handling parity error recovery. Try again later\n");
 		return -EAGAIN;

drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c

@@ -1843,6 +1843,12 @@ static int bnx2x_set_ringparam(struct net_device *dev,
 	   "set ring params command parameters: rx_pending = %d, tx_pending = %d\n",
 	   ering->rx_pending, ering->tx_pending);
 
+	if (pci_num_vf(bp->pdev)) {
+		DP(BNX2X_MSG_IOV,
+		   "VFs are enabled, can not change ring parameters\n");
+		return -EPERM;
+	}
+
 	if (bp->recovery_state != BNX2X_RECOVERY_DONE) {
 		DP(BNX2X_MSG_ETHTOOL,
 		   "Handling parity error recovery. Try again later\n");
@@ -2899,6 +2905,12 @@ static void bnx2x_self_test(struct net_device *dev,
 	u8 is_serdes, link_up;
 	int rc, cnt = 0;
 
+	if (pci_num_vf(bp->pdev)) {
+		DP(BNX2X_MSG_IOV,
+		   "VFs are enabled, can not perform self test\n");
+		return;
+	}
+
 	if (bp->recovery_state != BNX2X_RECOVERY_DONE) {
 		netdev_err(bp->dev,
 			   "Handling parity error recovery. Try again later\n");
@@ -3468,6 +3480,11 @@ static int bnx2x_set_channels(struct net_device *dev,
 	   channels->rx_count, channels->tx_count, channels->other_count,
 	   channels->combined_count);
 
+	if (pci_num_vf(bp->pdev)) {
+		DP(BNX2X_MSG_IOV, "VFs are enabled, can not set channels\n");
+		return -EPERM;
+	}
+
 	/* We don't support separate rx / tx channels.
 	 * We don't allow setting 'other' channels.
 	 */