4 files changed, 335 insertions, 26 deletions

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index 8b3bd8ecd1c4..6700a4dca7c8 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -202,6 +202,8 @@ int rndis_filter_receive(struct hv_device *dev,
 int rndis_filter_set_packet_filter(struct rndis_device *dev, u32 new_filter);
 int rndis_filter_set_device_mac(struct hv_device *hdev, char *mac);
 
+void netvsc_switch_datapath(struct netvsc_device *nv_dev, bool vf);
+
 #define NVSP_INVALID_PROTOCOL_VERSION	((u32)0xFFFFFFFF)
 
 #define NVSP_PROTOCOL_VERSION_1		2
@@ -641,6 +643,12 @@ struct netvsc_reconfig {
 	u32 event;
 };
 
+struct garp_wrk {
+	struct work_struct dwrk;
+	struct net_device *netdev;
+	struct netvsc_device *netvsc_dev;
+};
+
 /* The context of the netvsc device  */
 struct net_device_context {
 	/* point back to our device context */
@@ -656,6 +664,7 @@ struct net_device_context {
 
 	struct work_struct work;
 	u32 msg_enable; /* debug level */
+	struct garp_wrk gwrk;
 
 	struct netvsc_stats __percpu *tx_stats;
 	struct netvsc_stats __percpu *rx_stats;
@@ -730,6 +739,11 @@ struct netvsc_device {
 	u32 vf_alloc;
 	/* Serial number of the VF to team with */
 	u32 vf_serial;
+	atomic_t open_cnt;
+	/* State to manage the associated VF interface. */
+	bool vf_inject;
+	struct net_device *vf_netdev;
+	atomic_t vf_use_cnt;
 };
 
 /* NdisInitialize message */
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index ec313fc08d82..eddce3cdafa8 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -33,6 +33,30 @@
 
 #include "hyperv_net.h"
 
+/*
+ * Switch the data path from the synthetic interface to the VF
+ * interface.
+ */
+void netvsc_switch_datapath(struct netvsc_device *nv_dev, bool vf)
+{
+	struct nvsp_message *init_pkt = &nv_dev->channel_init_pkt;
+	struct hv_device *dev = nv_dev->dev;
+
+	memset(init_pkt, 0, sizeof(struct nvsp_message));
+	init_pkt->hdr.msg_type = NVSP_MSG4_TYPE_SWITCH_DATA_PATH;
+	if (vf)
+		init_pkt->msg.v4_msg.active_dp.active_datapath =
+			NVSP_DATAPATH_VF;
+	else
+		init_pkt->msg.v4_msg.active_dp.active_datapath =
+			NVSP_DATAPATH_SYNTHETIC;
+
+	vmbus_sendpacket(dev->channel, init_pkt,
+			       sizeof(struct nvsp_message),
+			       (unsigned long)init_pkt,
+			       VM_PKT_DATA_INBAND, 0);
+}
+
 
 static struct netvsc_device *alloc_net_device(struct hv_device *device)
 {
@@ -52,11 +76,16 @@ static struct netvsc_device *alloc_net_device(struct hv_device *device)
 	init_waitqueue_head(&net_device->wait_drain);
 	net_device->start_remove = false;
 	net_device->destroy = false;
+	atomic_set(&net_device->open_cnt, 0);
+	atomic_set(&net_device->vf_use_cnt, 0);
 	net_device->dev = device;
 	net_device->ndev = ndev;
 	net_device->max_pkt = RNDIS_MAX_PKT_DEFAULT;
 	net_device->pkt_align = RNDIS_PKT_ALIGN_DEFAULT;
 
+	net_device->vf_netdev = NULL;
+	net_device->vf_inject = false;
+
 	hv_set_drvdata(device, net_device);
 	return net_device;
 }
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index b8121eba33ff..bfdb568ac6b8 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -610,42 +610,24 @@ void netvsc_linkstatus_callback(struct hv_device *device_obj,
 	schedule_delayed_work(&ndev_ctx->dwork, 0);
 }
 
-/*
- * netvsc_recv_callback -  Callback when we receive a packet from the
- * "wire" on the specified device.
- */
-int netvsc_recv_callback(struct hv_device *device_obj,
+
+static struct sk_buff *netvsc_alloc_recv_skb(struct net_device *net,
 				struct hv_netvsc_packet *packet,
-				void **data,
 				struct ndis_tcp_ip_checksum_info *csum_info,
-				struct vmbus_channel *channel,
-				u16 vlan_tci)
+				void *data, u16 vlan_tci)
 {
-	struct net_device *net;
-	struct net_device_context *net_device_ctx;
 	struct sk_buff *skb;
-	struct netvsc_stats *rx_stats;
 
-	net = ((struct netvsc_device *)hv_get_drvdata(device_obj))->ndev;
-	if (!net || net->reg_state != NETREG_REGISTERED) {
-		return NVSP_STAT_FAIL;
-	}
-	net_device_ctx = netdev_priv(net);
-	rx_stats = this_cpu_ptr(net_device_ctx->rx_stats);
-
-	/* Allocate a skb - TODO direct I/O to pages? */
 	skb = netdev_alloc_skb_ip_align(net, packet->total_data_buflen);
-	if (unlikely(!skb)) {
-		++net->stats.rx_dropped;
-		return NVSP_STAT_FAIL;
-	}
+	if (!skb)
+		return skb;
 
 	/*
 	 * Copy to skb. This copy is needed here since the memory pointed by
 	 * hv_netvsc_packet cannot be deallocated
 	 */
-	memcpy(skb_put(skb, packet->total_data_buflen), *data,
-		packet->total_data_buflen);
+	memcpy(skb_put(skb, packet->total_data_buflen), data,
+	       packet->total_data_buflen);
 
 	skb->protocol = eth_type_trans(skb, net);
 	if (csum_info) {
@@ -663,6 +645,75 @@ int netvsc_recv_callback(struct hv_device *device_obj,
 		__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
 				       vlan_tci);
 
+	return skb;
+}
+
+/*
+ * netvsc_recv_callback -  Callback when we receive a packet from the
+ * "wire" on the specified device.
+ */
+int netvsc_recv_callback(struct hv_device *device_obj,
+				struct hv_netvsc_packet *packet,
+				void **data,
+				struct ndis_tcp_ip_checksum_info *csum_info,
+				struct vmbus_channel *channel,
+				u16 vlan_tci)
+{
+	struct net_device *net;
+	struct net_device_context *net_device_ctx;
+	struct sk_buff *skb;
+	struct sk_buff *vf_skb;
+	struct netvsc_stats *rx_stats;
+	struct netvsc_device *netvsc_dev = hv_get_drvdata(device_obj);
+	u32 bytes_recvd = packet->total_data_buflen;
+	int ret = 0;
+
+	net = netvsc_dev->ndev;
+	if (!net || net->reg_state != NETREG_REGISTERED)
+		return NVSP_STAT_FAIL;
+
+	if (READ_ONCE(netvsc_dev->vf_inject)) {
+		atomic_inc(&netvsc_dev->vf_use_cnt);
+		if (!READ_ONCE(netvsc_dev->vf_inject)) {
+			/*
+			 * We raced; just move on.
+			 */
+			atomic_dec(&netvsc_dev->vf_use_cnt);
+			goto vf_injection_done;
+		}
+
+		/*
+		 * Inject this packet into the VF inerface.
+		 * On Hyper-V, multicast and brodcast packets
+		 * are only delivered on the synthetic interface
+		 * (after subjecting these to policy filters on
+		 * the host). Deliver these via the VF interface
+		 * in the guest.
+		 */
+		vf_skb = netvsc_alloc_recv_skb(netvsc_dev->vf_netdev, packet,
+					       csum_info, *data, vlan_tci);
+		if (vf_skb != NULL) {
+			++netvsc_dev->vf_netdev->stats.rx_packets;
+			netvsc_dev->vf_netdev->stats.rx_bytes += bytes_recvd;
+			netif_receive_skb(vf_skb);
+		} else {
+			++net->stats.rx_dropped;
+			ret = NVSP_STAT_FAIL;
+		}
+		atomic_dec(&netvsc_dev->vf_use_cnt);
+		return ret;
+	}
+
+vf_injection_done:
+	net_device_ctx = netdev_priv(net);
+	rx_stats = this_cpu_ptr(net_device_ctx->rx_stats);
+
+	/* Allocate a skb - TODO direct I/O to pages? */
+	skb = netvsc_alloc_recv_skb(net, packet, csum_info, *data, vlan_tci);
+	if (unlikely(!skb)) {
+		++net->stats.rx_dropped;
+		return NVSP_STAT_FAIL;
+	}
 	skb_record_rx_queue(skb, channel->
 			    offermsg.offer.sub_channel_index);
 
@@ -1102,6 +1153,175 @@ static void netvsc_free_netdev(struct net_device *netdev)
 	free_netdev(netdev);
 }
 
+static void netvsc_notify_peers(struct work_struct *wrk)
+{
+	struct garp_wrk *gwrk;
+
+	gwrk = container_of(wrk, struct garp_wrk, dwrk);
+
+	netdev_notify_peers(gwrk->netdev);
+
+	atomic_dec(&gwrk->netvsc_dev->vf_use_cnt);
+}
+
+static struct netvsc_device *get_netvsc_device(char *mac)
+{
+	struct net_device *dev;
+	struct net_device_context *netvsc_ctx = NULL;
+	int rtnl_locked;
+
+	rtnl_locked = rtnl_trylock();
+
+	for_each_netdev(&init_net, dev) {
+		if (memcmp(dev->dev_addr, mac, ETH_ALEN) == 0) {
+			if (dev->netdev_ops != &device_ops)
+				continue;
+			netvsc_ctx = netdev_priv(dev);
+			break;
+		}
+	}
+	if (rtnl_locked)
+		rtnl_unlock();
+
+	if (netvsc_ctx == NULL)
+		return NULL;
+
+	return hv_get_drvdata(netvsc_ctx->device_ctx);
+}
+
+static int netvsc_register_vf(struct net_device *vf_netdev)
+{
+	struct netvsc_device *netvsc_dev;
+	const struct ethtool_ops *eth_ops = vf_netdev->ethtool_ops;
+
+	if (eth_ops == NULL || eth_ops == &ethtool_ops)
+		return NOTIFY_DONE;
+
+	/*
+	 * We will use the MAC address to locate the synthetic interface to
+	 * associate with the VF interface. If we don't find a matching
+	 * synthetic interface, move on.
+	 */
+	netvsc_dev = get_netvsc_device(vf_netdev->dev_addr);
+	if (netvsc_dev == NULL)
+		return NOTIFY_DONE;
+
+	netdev_info(netvsc_dev->ndev, "VF registering: %s\n", vf_netdev->name);
+	/*
+	 * Take a reference on the module.
+	 */
+	try_module_get(THIS_MODULE);
+	netvsc_dev->vf_netdev = vf_netdev;
+	return NOTIFY_OK;
+}
+
+
+static int netvsc_vf_up(struct net_device *vf_netdev)
+{
+	struct netvsc_device *netvsc_dev;
+	const struct ethtool_ops *eth_ops = vf_netdev->ethtool_ops;
+	struct net_device_context *net_device_ctx;
+
+	if (eth_ops == &ethtool_ops)
+		return NOTIFY_DONE;
+
+	netvsc_dev = get_netvsc_device(vf_netdev->dev_addr);
+
+	if ((netvsc_dev == NULL) || (netvsc_dev->vf_netdev == NULL))
+		return NOTIFY_DONE;
+
+	netdev_info(netvsc_dev->ndev, "VF up: %s\n", vf_netdev->name);
+	net_device_ctx = netdev_priv(netvsc_dev->ndev);
+	netvsc_dev->vf_inject = true;
+
+	/*
+	 * Open the device before switching data path.
+	 */
+	rndis_filter_open(net_device_ctx->device_ctx);
+
+	/*
+	 * notify the host to switch the data path.
+	 */
+	netvsc_switch_datapath(netvsc_dev, true);
+	netdev_info(netvsc_dev->ndev, "Data path switched to VF: %s\n",
+		    vf_netdev->name);
+
+	netif_carrier_off(netvsc_dev->ndev);
+
+	/*
+	 * Now notify peers. We are scheduling work to
+	 * notify peers; take a reference to prevent
+	 * the VF interface from vanishing.
+	 */
+	atomic_inc(&netvsc_dev->vf_use_cnt);
+	net_device_ctx->gwrk.netdev = vf_netdev;
+	net_device_ctx->gwrk.netvsc_dev = netvsc_dev;
+	schedule_work(&net_device_ctx->gwrk.dwrk);
+
+	return NOTIFY_OK;
+}
+
+
+static int netvsc_vf_down(struct net_device *vf_netdev)
+{
+	struct netvsc_device *netvsc_dev;
+	struct net_device_context *net_device_ctx;
+	const struct ethtool_ops *eth_ops = vf_netdev->ethtool_ops;
+
+	if (eth_ops == &ethtool_ops)
+		return NOTIFY_DONE;
+
+	netvsc_dev = get_netvsc_device(vf_netdev->dev_addr);
+
+	if ((netvsc_dev == NULL) || (netvsc_dev->vf_netdev == NULL))
+		return NOTIFY_DONE;
+
+	netdev_info(netvsc_dev->ndev, "VF down: %s\n", vf_netdev->name);
+	net_device_ctx = netdev_priv(netvsc_dev->ndev);
+	netvsc_dev->vf_inject = false;
+	/*
+	 * Wait for currently active users to
+	 * drain out.
+	 */
+
+	while (atomic_read(&netvsc_dev->vf_use_cnt) != 0)
+		udelay(50);
+	netvsc_switch_datapath(netvsc_dev, false);
+	netdev_info(netvsc_dev->ndev, "Data path switched from VF: %s\n",
+		    vf_netdev->name);
+	rndis_filter_close(net_device_ctx->device_ctx);
+	netif_carrier_on(netvsc_dev->ndev);
+	/*
+	 * Notify peers.
+	 */
+	atomic_inc(&netvsc_dev->vf_use_cnt);
+	net_device_ctx->gwrk.netdev = netvsc_dev->ndev;
+	net_device_ctx->gwrk.netvsc_dev = netvsc_dev;
+	schedule_work(&net_device_ctx->gwrk.dwrk);
+
+	return NOTIFY_OK;
+}
+
+
+static int netvsc_unregister_vf(struct net_device *vf_netdev)
+{
+	struct netvsc_device *netvsc_dev;
+	const struct ethtool_ops *eth_ops = vf_netdev->ethtool_ops;
+
+	if (eth_ops == &ethtool_ops)
+		return NOTIFY_DONE;
+
+	netvsc_dev = get_netvsc_device(vf_netdev->dev_addr);
+	if (netvsc_dev == NULL)
+		return NOTIFY_DONE;
+	netdev_info(netvsc_dev->ndev, "VF unregistering: %s\n",
+		    vf_netdev->name);
+
+	netvsc_dev->vf_netdev = NULL;
+	module_put(THIS_MODULE);
+	return NOTIFY_OK;
+}
+
 static int netvsc_probe(struct hv_device *dev,
 			const struct hv_vmbus_device_id *dev_id)
 {
@@ -1140,6 +1360,7 @@ static int netvsc_probe(struct hv_device *dev,
 	hv_set_drvdata(dev, net);
 	INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_link_change);
 	INIT_WORK(&net_device_ctx->work, do_set_multicast);
+	INIT_WORK(&net_device_ctx->gwrk.dwrk, netvsc_notify_peers);
 
 	spin_lock_init(&net_device_ctx->lock);
 	INIT_LIST_HEAD(&net_device_ctx->reconfig_events);
@@ -1235,19 +1456,58 @@ static struct  hv_driver netvsc_drv = {
 	.remove = netvsc_remove,
 };
 
+
+/*
+ * On Hyper-V, every VF interface is matched with a corresponding
+ * synthetic interface. The synthetic interface is presented first
+ * to the guest. When the corresponding VF instance is registered,
+ * we will take care of switching the data path.
+ */
+static int netvsc_netdev_event(struct notifier_block *this,
+			       unsigned long event, void *ptr)
+{
+	struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
+
+	switch (event) {
+	case NETDEV_REGISTER:
+		return netvsc_register_vf(event_dev);
+	case NETDEV_UNREGISTER:
+		return netvsc_unregister_vf(event_dev);
+	case NETDEV_UP:
+		return netvsc_vf_up(event_dev);
+	case NETDEV_DOWN:
+		return netvsc_vf_down(event_dev);
+	default:
+		return NOTIFY_DONE;
+	}
+}
+
+static struct notifier_block netvsc_netdev_notifier = {
+	.notifier_call = netvsc_netdev_event,
+};
+
 static void __exit netvsc_drv_exit(void)
 {
+	unregister_netdevice_notifier(&netvsc_netdev_notifier);
 	vmbus_driver_unregister(&netvsc_drv);
 }
 
 static int __init netvsc_drv_init(void)
 {
+	int ret;
+
 	if (ring_size < RING_SIZE_MIN) {
 		ring_size = RING_SIZE_MIN;
 		pr_info("Increased ring_size to %d (min allowed)\n",
 			ring_size);
 	}
-	return vmbus_driver_register(&netvsc_drv);
+	ret = vmbus_driver_register(&netvsc_drv);
+
+	if (ret)
+		return ret;
+
+	register_netdevice_notifier(&netvsc_netdev_notifier);
+	return 0;
 }
 
 MODULE_LICENSE("GPL");
diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index c4e1e0408433..a59cdebc9b4b 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -1229,6 +1229,9 @@ int rndis_filter_open(struct hv_device *dev)
 	if (!net_device)
 		return -EINVAL;
 
+	if (atomic_inc_return(&net_device->open_cnt) != 1)
+		return 0;
+
 	return rndis_filter_open_device(net_device->extension);
 }
 
@@ -1239,5 +1242,8 @@ int rndis_filter_close(struct hv_device *dev)
 	if (!nvdev)
 		return -EINVAL;
 
+	if (atomic_dec_return(&nvdev->open_cnt) != 0)
+		return 0;
+
 	return rndis_filter_close_device(nvdev->extension);
 }