Commit d0922bf7 authored by Haiyang Zhang's avatar Haiyang Zhang Committed by David S. Miller
Browse files

hv_netvsc: Add error handling while switching data path 



Add error handling in case of failure to send switching data path message
to the host.

Reported-by: default avatarShachar Raindel <shacharr@microsoft.com>
Signed-off-by: default avatarHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent d24f511b

drivers/net/hyperv/hyperv_net.h

+5 −1
Original line number Diff line number Diff line
@@ -269,7 +269,7 @@ int rndis_filter_receive(struct net_device *ndev, 
int rndis_filter_set_device_mac(struct netvsc_device *ndev,

				const char *mac);



void netvsc_switch_datapath(struct net_device *nv_dev, bool vf);

int netvsc_switch_datapath(struct net_device *nv_dev, bool vf);



#define NVSP_INVALID_PROTOCOL_VERSION	((u32)0xFFFFFFFF)
@@ -1718,4 +1718,8 @@ struct rndis_message { 
#define TRANSPORT_INFO_IPV6_TCP 0x10

#define TRANSPORT_INFO_IPV6_UDP 0x20



#define RETRY_US_LO	5000

#define RETRY_US_HI	10000

#define RETRY_MAX	2000	/* >10 sec */



#endif /* _HYPERV_NET_H */

drivers/net/hyperv/netvsc.c

+31 −4
Original line number Diff line number Diff line
@@ -31,12 +31,13 @@ 
 * Switch the data path from the synthetic interface to the VF

 * interface.

 */

void netvsc_switch_datapath(struct net_device *ndev, bool vf)

int netvsc_switch_datapath(struct net_device *ndev, bool vf)

{

	struct net_device_context *net_device_ctx = netdev_priv(ndev);

	struct hv_device *dev = net_device_ctx->device_ctx;

	struct netvsc_device *nv_dev = rtnl_dereference(net_device_ctx->nvdev);

	struct nvsp_message *init_pkt = &nv_dev->channel_init_pkt;

	int ret, retry = 0;



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

	if (!vf)
@@ -51,15 +52,41 @@ void netvsc_switch_datapath(struct net_device *ndev, bool vf) 
		init_pkt->msg.v4_msg.active_dp.active_datapath =

			NVSP_DATAPATH_SYNTHETIC;



again:

	trace_nvsp_send(ndev, init_pkt);



	vmbus_sendpacket(dev->channel, init_pkt,

	ret = vmbus_sendpacket(dev->channel, init_pkt,

			       sizeof(struct nvsp_message),

			       (unsigned long)init_pkt,

			       VM_PKT_DATA_INBAND,

			       (unsigned long)init_pkt, VM_PKT_DATA_INBAND,

			       VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);



	/* If failed to switch to/from VF, let data_path_is_vf stay false,

	 * so we use synthetic path to send data.

	 */

	if (ret) {

		if (ret != -EAGAIN) {

			netdev_err(ndev,

				   "Unable to send sw datapath msg, err: %d\n",

				   ret);

			return ret;

		}



		if (retry++ < RETRY_MAX) {

			usleep_range(RETRY_US_LO, RETRY_US_HI);

			goto again;

		} else {

			netdev_err(

				ndev,

				"Retry failed to send sw datapath msg, err: %d\n",

				ret);

			return ret;

		}

	}



	wait_for_completion(&nv_dev->channel_init_wait);

	net_device_ctx->data_path_is_vf = vf;



	return 0;

}



/* Worker to setup sub channels on initial setup

drivers/net/hyperv/netvsc_drv.c

+12 −6
Original line number Diff line number Diff line
@@ -38,9 +38,6 @@ 
#include "hyperv_net.h"



#define RING_SIZE_MIN	64

#define RETRY_US_LO	5000

#define RETRY_US_HI	10000

#define RETRY_MAX	2000	/* >10 sec */



#define LINKCHANGE_INT (2 * HZ)

#define VF_TAKEOVER_INT (HZ / 10)
@@ -2402,6 +2399,7 @@ static int netvsc_vf_changed(struct net_device *vf_netdev, unsigned long event) 
	struct netvsc_device *netvsc_dev;

	struct net_device *ndev;

	bool vf_is_up = false;

	int ret;



	if (event != NETDEV_GOING_DOWN)

		vf_is_up = netif_running(vf_netdev);
@@ -2418,9 +2416,17 @@ static int netvsc_vf_changed(struct net_device *vf_netdev, unsigned long event) 
	if (net_device_ctx->data_path_is_vf == vf_is_up)

		return NOTIFY_OK;



	netvsc_switch_datapath(ndev, vf_is_up);

	ret = netvsc_switch_datapath(ndev, vf_is_up);



	if (ret) {

		netdev_err(ndev,

			   "Data path failed to switch %s VF: %s, err: %d\n",

			   vf_is_up ? "to" : "from", vf_netdev->name, ret);

		return NOTIFY_DONE;

	} else {

		netdev_info(ndev, "Data path switched %s VF: %s\n",

			    vf_is_up ? "to" : "from", vf_netdev->name);

	}



	return NOTIFY_OK;

}