1 files changed, 66 insertions, 5 deletions

diff --git a/drivers/net/enic/enic_main.c b/drivers/net/enic/enic_main.c
index 5b087ebe632d..1daf79b36165 100644
--- a/drivers/net/enic/enic_main.c
+++ b/drivers/net/enic/enic_main.c
@@ -423,11 +423,18 @@ static void enic_mtu_check(struct enic *enic)
 
 	if (mtu && mtu != enic->port_mtu) {
 		enic->port_mtu = mtu;
-		if (mtu < netdev->mtu)
-			netdev_warn(netdev,
-				"interface MTU (%d) set higher "
-				"than switch port MTU (%d)\n",
-				netdev->mtu, mtu);
+		if (enic_is_dynamic(enic)) {
+			mtu = max_t(int, ENIC_MIN_MTU,
+				min_t(int, ENIC_MAX_MTU, mtu));
+			if (mtu != netdev->mtu)
+				schedule_work(&enic->change_mtu_work);
+		} else {
+			if (mtu < netdev->mtu)
+				netdev_warn(netdev,
+					"interface MTU (%d) set higher "
+					"than switch port MTU (%d)\n",
+					netdev->mtu, mtu);
+		}
 	}
 }
 
@@ -1688,6 +1695,9 @@ static int enic_change_mtu(struct net_device *netdev, int new_mtu)
 	if (new_mtu < ENIC_MIN_MTU || new_mtu > ENIC_MAX_MTU)
 		return -EINVAL;
 
+	if (enic_is_dynamic(enic))
+		return -EOPNOTSUPP;
+
 	if (running)
 		enic_stop(netdev);
 
@@ -1704,6 +1714,55 @@ static int enic_change_mtu(struct net_device *netdev, int new_mtu)
 	return 0;
 }
 
+static void enic_change_mtu_work(struct work_struct *work)
+{
+	struct enic *enic = container_of(work, struct enic, change_mtu_work);
+	struct net_device *netdev = enic->netdev;
+	int new_mtu = vnic_dev_mtu(enic->vdev);
+	int err;
+	unsigned int i;
+
+	new_mtu = max_t(int, ENIC_MIN_MTU, min_t(int, ENIC_MAX_MTU, new_mtu));
+
+	rtnl_lock();
+
+	/* Stop RQ */
+	del_timer_sync(&enic->notify_timer);
+
+	for (i = 0; i < enic->rq_count; i++)
+		napi_disable(&enic->napi[i]);
+
+	vnic_intr_mask(&enic->intr[0]);
+	enic_synchronize_irqs(enic);
+	err = vnic_rq_disable(&enic->rq[0]);
+	if (err) {
+		netdev_err(netdev, "Unable to disable RQ.\n");
+		return;
+	}
+	vnic_rq_clean(&enic->rq[0], enic_free_rq_buf);
+	vnic_cq_clean(&enic->cq[0]);
+	vnic_intr_clean(&enic->intr[0]);
+
+	/* Fill RQ with new_mtu-sized buffers */
+	netdev->mtu = new_mtu;
+	vnic_rq_fill(&enic->rq[0], enic_rq_alloc_buf);
+	/* Need at least one buffer on ring to get going */
+	if (vnic_rq_desc_used(&enic->rq[0]) == 0) {
+		netdev_err(netdev, "Unable to alloc receive buffers.\n");
+		return;
+	}
+
+	/* Start RQ */
+	vnic_rq_enable(&enic->rq[0]);
+	napi_enable(&enic->napi[0]);
+	vnic_intr_unmask(&enic->intr[0]);
+	enic_notify_timer_start(enic);
+
+	rtnl_unlock();
+
+	netdev_info(netdev, "interface MTU set as %d\n", netdev->mtu);
+}
+
 #ifdef CONFIG_NET_POLL_CONTROLLER
 static void enic_poll_controller(struct net_device *netdev)
 {
@@ -2345,6 +2404,7 @@ static int __devinit enic_probe(struct pci_dev *pdev,
 	enic->notify_timer.data = (unsigned long)enic;
 
 	INIT_WORK(&enic->reset, enic_reset);
+	INIT_WORK(&enic->change_mtu_work, enic_change_mtu_work);
 
 	for (i = 0; i < enic->wq_count; i++)
 		spin_lock_init(&enic->wq_lock[i]);
@@ -2427,6 +2487,7 @@ static void __devexit enic_remove(struct pci_dev *pdev)
 		struct enic *enic = netdev_priv(netdev);
 
 		cancel_work_sync(&enic->reset);
+		cancel_work_sync(&enic->change_mtu_work);
 		unregister_netdev(netdev);
 		enic_dev_deinit(enic);
 		vnic_dev_close(enic->vdev);