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 <[e-mail]>
Signed-off-by: Ariel Elior <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

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

···
 {
 	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;
···
 	else
 		flags &= ~GRO_ENABLE_FLAG;
 
-	if (features & NETIF_F_LOOPBACK) {
-		if (bp->link_params.loopback_mode != LOOPBACK_BMAC) {
-			bp->link_params.loopback_mode = LOOPBACK_BMAC;
-			bnx2x_reload = true;
-		}
-	} else {
-		if (bp->link_params.loopback_mode != LOOPBACK_NONE) {
-			bp->link_params.loopback_mode = LOOPBACK_NONE;
-			bnx2x_reload = true;
+	/* 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;
+				bnx2x_reload = true;
+			}
+		} else {
+			if (bp->link_params.loopback_mode != LOOPBACK_NONE) {
+				bp->link_params.loopback_mode = LOOPBACK_NONE;
+				bnx2x_reload = true;
+			}
 		}
 	}
 
···
 		return -ENODEV;
 	}
 	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");

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

···
 	   "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");
···
 	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");
···
 	   "set-channels command parameters: rx = %d, tx = %d, other = %d, combined = %d\n",
 	   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.