Commit b866e72c authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge branch 'hv_netvsc-prevent-packet-loss-during-vf-add-remove' 

Long Li says:

====================
hv_netvsc: Prevent packet loss during VF add/remove

This patch set fixes issues with packet loss on VF add/remove.
====================

Link: https://lore.kernel.org/r/1610153623-17500-1-git-send-email-longli@linuxonhyperv.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents 2c82b7fe 34b06a2e

drivers/net/hyperv/netvsc.c

+34 −3
Original line number Diff line number Diff line
@@ -37,6 +37,10 @@ void netvsc_switch_datapath(struct net_device *ndev, bool vf) 
	struct netvsc_device *nv_dev = rtnl_dereference(net_device_ctx->nvdev);

	struct nvsp_message *init_pkt = &nv_dev->channel_init_pkt;



	/* Block sending traffic to VF if it's about to be gone */

	if (!vf)

		net_device_ctx->data_path_is_vf = vf;



	memset(init_pkt, 0, sizeof(struct nvsp_message));

	init_pkt->hdr.msg_type = NVSP_MSG4_TYPE_SWITCH_DATA_PATH;

	if (vf)
@@ -50,8 +54,11 @@ void netvsc_switch_datapath(struct net_device *ndev, bool vf) 


	vmbus_sendpacket(dev->channel, init_pkt,

			       sizeof(struct nvsp_message),

			       VMBUS_RQST_ID_NO_RESPONSE,

			       VM_PKT_DATA_INBAND, 0);

			       (unsigned long)init_pkt,

			       VM_PKT_DATA_INBAND,

			       VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);

	wait_for_completion(&nv_dev->channel_init_wait);

	net_device_ctx->data_path_is_vf = vf;

}



/* Worker to setup sub channels on initial setup
@@ -754,8 +761,31 @@ static void netvsc_send_completion(struct net_device *ndev, 
				   const struct vmpacket_descriptor *desc,

				   int budget)

{

	const struct nvsp_message *nvsp_packet = hv_pkt_data(desc);

	const struct nvsp_message *nvsp_packet;

	u32 msglen = hv_pkt_datalen(desc);

	struct nvsp_message *pkt_rqst;

	u64 cmd_rqst;



	/* First check if this is a VMBUS completion without data payload */

	if (!msglen) {

		cmd_rqst = vmbus_request_addr(&incoming_channel->requestor,

					      (u64)desc->trans_id);

		if (cmd_rqst == VMBUS_RQST_ERROR) {

			netdev_err(ndev, "Invalid transaction id\n");

			return;

		}



		pkt_rqst = (struct nvsp_message *)(uintptr_t)cmd_rqst;

		switch (pkt_rqst->hdr.msg_type) {

		case NVSP_MSG4_TYPE_SWITCH_DATA_PATH:

			complete(&net_device->channel_init_wait);

			break;



		default:

			netdev_err(ndev, "Unexpected VMBUS completion!!\n");

		}

		return;

	}



	/* Ensure packet is big enough to read header fields */

	if (msglen < sizeof(struct nvsp_message_header)) {
@@ -763,6 +793,7 @@ static void netvsc_send_completion(struct net_device *ndev, 
		return;

	}



	nvsp_packet = hv_pkt_data(desc);

	switch (nvsp_packet->hdr.msg_type) {

	case NVSP_MSG_TYPE_INIT_COMPLETE:

		if (msglen < sizeof(struct nvsp_message_header) +

drivers/net/hyperv/netvsc_drv.c

+9 −5
Original line number Diff line number Diff line
@@ -539,7 +539,8 @@ static int netvsc_xmit(struct sk_buff *skb, struct net_device *net, bool xdp_tx) 
	 */

	vf_netdev = rcu_dereference_bh(net_device_ctx->vf_netdev);

	if (vf_netdev && netif_running(vf_netdev) &&

	    netif_carrier_ok(vf_netdev) && !netpoll_tx_running(net))

	    netif_carrier_ok(vf_netdev) && !netpoll_tx_running(net) &&

	    net_device_ctx->data_path_is_vf)

		return netvsc_vf_xmit(net, vf_netdev, skb);



	/* We will atmost need two pages to describe the rndis
@@ -2381,12 +2382,15 @@ static int netvsc_register_vf(struct net_device *vf_netdev) 
 * During hibernation, if a VF NIC driver (e.g. mlx5) preserves the network

 * interface, there is only the CHANGE event and no UP or DOWN event.

 */

static int netvsc_vf_changed(struct net_device *vf_netdev)

static int netvsc_vf_changed(struct net_device *vf_netdev, unsigned long event)

{

	struct net_device_context *net_device_ctx;

	struct netvsc_device *netvsc_dev;

	struct net_device *ndev;

	bool vf_is_up = netif_running(vf_netdev);

	bool vf_is_up = false;



	if (event != NETDEV_GOING_DOWN)

		vf_is_up = netif_running(vf_netdev);



	ndev = get_netvsc_byref(vf_netdev);

	if (!ndev)
@@ -2399,7 +2403,6 @@ static int netvsc_vf_changed(struct net_device *vf_netdev) 


	if (net_device_ctx->data_path_is_vf == vf_is_up)

		return NOTIFY_OK;

	net_device_ctx->data_path_is_vf = vf_is_up;



	netvsc_switch_datapath(ndev, vf_is_up);

	netdev_info(ndev, "Data path switched %s VF: %s\n",
@@ -2716,7 +2719,8 @@ static int netvsc_netdev_event(struct notifier_block *this, 
	case NETDEV_UP:

	case NETDEV_DOWN:

	case NETDEV_CHANGE:

		return netvsc_vf_changed(event_dev);

	case NETDEV_GOING_DOWN:

		return netvsc_vf_changed(event_dev, event);

	default:

		return NOTIFY_DONE;

	}