[PATCH net,v3] hyperv: Fix the carrier status setting

[PATCH net,v3] hyperv: Fix the carrier status setting

[Haiyang Zhang]

Without this patch, the "cat /sys/class/net/ethN/operstate" shows
"unknown", and "ethtool ethN" shows "Link detected: yes", when VM
boots up with or without vNIC connected.

This patch fixed the problem.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
---
 drivers/net/hyperv/netvsc_drv.c |   53 ++++++++++++++++++++++++++++-----------
 1 files changed, 38 insertions(+), 15 deletions(-)

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 7756118..7141a19 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -88,8 +88,12 @@ static int netvsc_open(struct net_device *net)
 {
 	struct net_device_context *net_device_ctx = netdev_priv(net);
 	struct hv_device *device_obj = net_device_ctx->device_ctx;
+	struct netvsc_device *nvdev;
+	struct rndis_device *rdev;
 	int ret = 0;
 
+	netif_carrier_off(net);
+
 	/* Open up the device */
 	ret = rndis_filter_open(device_obj);
 	if (ret != 0) {
@@ -99,6 +103,11 @@ static int netvsc_open(struct net_device *net)
 
 	netif_start_queue(net);
 
+	nvdev = hv_get_drvdata(device_obj);
+	rdev = nvdev->extension;
+	if (!rdev->link_state)
+		netif_carrier_on(net);
+
 	return ret;
 }
 
@@ -229,23 +238,24 @@ void netvsc_linkstatus_callback(struct hv_device *device_obj,
 	struct net_device *net;
 	struct net_device_context *ndev_ctx;
 	struct netvsc_device *net_device;
+	struct rndis_device *rdev;
 
 	net_device = hv_get_drvdata(device_obj);
+	rdev = net_device->extension;
+
+	rdev->link_state = status != 1;
+
 	net = net_device->ndev;
 
-	if (!net) {
-		netdev_err(net, "got link status but net device "
-				"not initialized yet\n");
+	if (!net || net->reg_state != NETREG_REGISTERED)
 		return;
-	}
 
+	ndev_ctx = netdev_priv(net);
 	if (status == 1) {
-		netif_carrier_on(net);
-		ndev_ctx = netdev_priv(net);
 		schedule_delayed_work(&ndev_ctx->dwork, 0);
 		schedule_delayed_work(&ndev_ctx->dwork, msecs_to_jiffies(20));
 	} else {
-		netif_carrier_off(net);
+		schedule_delayed_work(&ndev_ctx->dwork, 0);
 	}
 }
 
@@ -388,17 +398,35 @@ static const struct net_device_ops device_ops = {
  * current context when receiving RNDIS_STATUS_MEDIA_CONNECT event. So, add
  * another netif_notify_peers() into a delayed work, otherwise GARP packet
  * will not be sent after quick migration, and cause network disconnection.
+ * Also, we update the carrier status here.
  */
-static void netvsc_send_garp(struct work_struct *w)
+static void netvsc_link_change(struct work_struct *w)
 {
 	struct net_device_context *ndev_ctx;
 	struct net_device *net;
 	struct netvsc_device *net_device;
+	struct rndis_device *rdev;
+	bool notify;
+
+	rtnl_lock();
 
 	ndev_ctx = container_of(w, struct net_device_context, dwork.work);
 	net_device = hv_get_drvdata(ndev_ctx->device_ctx);
+	rdev = net_device->extension;
 	net = net_device->ndev;
-	netdev_notify_peers(net);
+
+	if (rdev->link_state) {
+		netif_carrier_off(net);
+		notify = false;
+	} else {
+		netif_carrier_on(net);
+		notify = true;
+	}
+
+	rtnl_unlock();
+
+	if (notify)
+		netdev_notify_peers(net);
 }
 
 
@@ -414,13 +442,10 @@ static int netvsc_probe(struct hv_device *dev,
 	if (!net)
 		return -ENOMEM;
 
-	/* Set initial state */
-	netif_carrier_off(net);
-
 	net_device_ctx = netdev_priv(net);
 	net_device_ctx->device_ctx = dev;
 	hv_set_drvdata(dev, net);
-	INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_send_garp);
+	INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_link_change);
 	INIT_WORK(&net_device_ctx->work, do_set_multicast);
 
 	net->netdev_ops = &device_ops;
@@ -443,8 +468,6 @@ static int netvsc_probe(struct hv_device *dev,
 	}
 	memcpy(net->dev_addr, device_info.mac_adr, ETH_ALEN);
 
-	netif_carrier_on(net);
-
 	ret = register_netdev(net);
 	if (ret != 0) {
 		pr_err("Unable to register netdev.\n");
-- 
1.7.4.1

Re: [PATCH net,v3] hyperv: Fix the carrier status setting

[Jason Wang]

On 02/13/2014 08:54 AM, Haiyang Zhang wrote:
> Without this patch, the "cat /sys/class/net/ethN/operstate" shows
> "unknown", and "ethtool ethN" shows "Link detected: yes", when VM
> boots up with or without vNIC connected.
>
> This patch fixed the problem.
>
> Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
> Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
> ---
>  drivers/net/hyperv/netvsc_drv.c |   53 ++++++++++++++++++++++++++++-----------
>  1 files changed, 38 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
> index 7756118..7141a19 100644
> --- a/drivers/net/hyperv/netvsc_drv.c
> +++ b/drivers/net/hyperv/netvsc_drv.c
> @@ -88,8 +88,12 @@ static int netvsc_open(struct net_device *net)
>  {
>  	struct net_device_context *net_device_ctx = netdev_priv(net);
>  	struct hv_device *device_obj = net_device_ctx->device_ctx;
> +	struct netvsc_device *nvdev;
> +	struct rndis_device *rdev;
>  	int ret = 0;
>  
> +	netif_carrier_off(net);
> +
>  	/* Open up the device */
>  	ret = rndis_filter_open(device_obj);
>  	if (ret != 0) {
> @@ -99,6 +103,11 @@ static int netvsc_open(struct net_device *net)
>  
>  	netif_start_queue(net);
>  
> +	nvdev = hv_get_drvdata(device_obj);
> +	rdev = nvdev->extension;
> +	if (!rdev->link_state)
> +		netif_carrier_on(net);
> +

Maybe you can just schedule the work here and then you can drop the
rtnl_lock in netvsc_link_change() ?
>  	return ret;
>  }
>  
> @@ -229,23 +238,24 @@ void netvsc_linkstatus_callback(struct hv_device *device_obj,
>  	struct net_device *net;
>  	struct net_device_context *ndev_ctx;
>  	struct netvsc_device *net_device;
> +	struct rndis_device *rdev;
>  
>  	net_device = hv_get_drvdata(device_obj);
> +	rdev = net_device->extension;
> +
> +	rdev->link_state = status != 1;
> +
>  	net = net_device->ndev;
>  
> -	if (!net) {
> -		netdev_err(net, "got link status but net device "
> -				"not initialized yet\n");
> +	if (!net || net->reg_state != NETREG_REGISTERED)
>  		return;
> -	}
>  
> +	ndev_ctx = netdev_priv(net);
>  	if (status == 1) {
> -		netif_carrier_on(net);
> -		ndev_ctx = netdev_priv(net);
>  		schedule_delayed_work(&ndev_ctx->dwork, 0);
>  		schedule_delayed_work(&ndev_ctx->dwork, msecs_to_jiffies(20));
>  	} else {
> -		netif_carrier_off(net);
> +		schedule_delayed_work(&ndev_ctx->dwork, 0);
>  	}
>  }
>  
> @@ -388,17 +398,35 @@ static const struct net_device_ops device_ops = {
>   * current context when receiving RNDIS_STATUS_MEDIA_CONNECT event. So, add
>   * another netif_notify_peers() into a delayed work, otherwise GARP packet
>   * will not be sent after quick migration, and cause network disconnection.
> + * Also, we update the carrier status here.
>   */
> -static void netvsc_send_garp(struct work_struct *w)
> +static void netvsc_link_change(struct work_struct *w)
>  {
>  	struct net_device_context *ndev_ctx;
>  	struct net_device *net;
>  	struct netvsc_device *net_device;
> +	struct rndis_device *rdev;
> +	bool notify;
> +
> +	rtnl_lock();
>  
>  	ndev_ctx = container_of(w, struct net_device_context, dwork.work);
>  	net_device = hv_get_drvdata(ndev_ctx->device_ctx);
> +	rdev = net_device->extension;
>  	net = net_device->ndev;
> -	netdev_notify_peers(net);
> +
> +	if (rdev->link_state) {
> +		netif_carrier_off(net);
> +		notify = false;
> +	} else {
> +		netif_carrier_on(net);
> +		notify = true;
> +	}
> +
> +	rtnl_unlock();
> +
> +	if (notify)
> +		netdev_notify_peers(net);
>  }
>  

Looks like this forces arp_notify here. Is it expected?

Other looks good.
>  
> @@ -414,13 +442,10 @@ static int netvsc_probe(struct hv_device *dev,
>  	if (!net)
>  		return -ENOMEM;
>  
> -	/* Set initial state */
> -	netif_carrier_off(net);
> -
>  	net_device_ctx = netdev_priv(net);
>  	net_device_ctx->device_ctx = dev;
>  	hv_set_drvdata(dev, net);
> -	INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_send_garp);
> +	INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_link_change);
>  	INIT_WORK(&net_device_ctx->work, do_set_multicast);
>  
>  	net->netdev_ops = &device_ops;
> @@ -443,8 +468,6 @@ static int netvsc_probe(struct hv_device *dev,
>  	}
>  	memcpy(net->dev_addr, device_info.mac_adr, ETH_ALEN);
>  
> -	netif_carrier_on(net);
> -
>  	ret = register_netdev(net);
>  	if (ret != 0) {
>  		pr_err("Unable to register netdev.\n");

RE: [PATCH net,v3] hyperv: Fix the carrier status setting

[Haiyang Zhang]

> -----Original Message-----
> From: Jason Wang [mailto:jasowang@redhat.com]
> Sent: Wednesday, February 12, 2014 10:52 PM
> To: Haiyang Zhang; davem@davemloft.net; netdev@vger.kernel.org
> Cc: KY Srinivasan; olaf@aepfle.de; linux-kernel@vger.kernel.org; driverdev-
> devel@linuxdriverproject.org
> Subject: Re: [PATCH net,v3] hyperv: Fix the carrier status setting
> 
> On 02/13/2014 08:54 AM, Haiyang Zhang wrote:
> > Without this patch, the "cat /sys/class/net/ethN/operstate" shows
> > "unknown", and "ethtool ethN" shows "Link detected: yes", when VM
> > boots up with or without vNIC connected.
> >
> > This patch fixed the problem.
> >
> > Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
> > Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
> > ---
> >  drivers/net/hyperv/netvsc_drv.c |   53
> ++++++++++++++++++++++++++++-----------
> >  1 files changed, 38 insertions(+), 15 deletions(-)
> >
> > diff --git a/drivers/net/hyperv/netvsc_drv.c
> > b/drivers/net/hyperv/netvsc_drv.c index 7756118..7141a19 100644
> > --- a/drivers/net/hyperv/netvsc_drv.c
> > +++ b/drivers/net/hyperv/netvsc_drv.c
> > @@ -88,8 +88,12 @@ static int netvsc_open(struct net_device *net)  {
> >  	struct net_device_context *net_device_ctx = netdev_priv(net);
> >  	struct hv_device *device_obj = net_device_ctx->device_ctx;
> > +	struct netvsc_device *nvdev;
> > +	struct rndis_device *rdev;
> >  	int ret = 0;
> >
> > +	netif_carrier_off(net);
> > +
> >  	/* Open up the device */
> >  	ret = rndis_filter_open(device_obj);
> >  	if (ret != 0) {
> > @@ -99,6 +103,11 @@ static int netvsc_open(struct net_device *net)
> >
> >  	netif_start_queue(net);
> >
> > +	nvdev = hv_get_drvdata(device_obj);
> > +	rdev = nvdev->extension;
> > +	if (!rdev->link_state)
> > +		netif_carrier_on(net);
> > +
> 
> Maybe you can just schedule the work here and then you can drop the
> rtnl_lock in netvsc_link_change() ?

The rtnl_lock will still be necessary in the netvsc_link_change(), because 
we want to prevent it getting wrong rdev pointer when netvsc_change_mtu
is removing/adding rndis device.

> > +
> > +	if (notify)
> > +		netdev_notify_peers(net);
> >  }
> >
> 
> Looks like this forces arp_notify here. Is it expected?

Yes, this is expected. It's required after live migration.

Thanks,
- Haiyang

Re: [PATCH net,v3] hyperv: Fix the carrier status setting

[Jason Wang]

On 02/13/2014 11:04 PM, Haiyang Zhang wrote:
>
>> -----Original Message-----
>> From: Jason Wang [mailto:jasowang@redhat.com]
>> Sent: Wednesday, February 12, 2014 10:52 PM
>> To: Haiyang Zhang; davem@davemloft.net; netdev@vger.kernel.org
>> Cc: KY Srinivasan; olaf@aepfle.de; linux-kernel@vger.kernel.org; driverdev-
>> devel@linuxdriverproject.org
>> Subject: Re: [PATCH net,v3] hyperv: Fix the carrier status setting
>>
>> On 02/13/2014 08:54 AM, Haiyang Zhang wrote:
>>> Without this patch, the "cat /sys/class/net/ethN/operstate" shows
>>> "unknown", and "ethtool ethN" shows "Link detected: yes", when VM
>>> boots up with or without vNIC connected.
>>>
>>> This patch fixed the problem.
>>>
>>> Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
>>> Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
>>> ---
>>>  drivers/net/hyperv/netvsc_drv.c |   53
>> ++++++++++++++++++++++++++++-----------
>>>  1 files changed, 38 insertions(+), 15 deletions(-)
>>>
>>> diff --git a/drivers/net/hyperv/netvsc_drv.c
>>> b/drivers/net/hyperv/netvsc_drv.c index 7756118..7141a19 100644
>>> --- a/drivers/net/hyperv/netvsc_drv.c
>>> +++ b/drivers/net/hyperv/netvsc_drv.c
>>> @@ -88,8 +88,12 @@ static int netvsc_open(struct net_device *net)  {
>>>  	struct net_device_context *net_device_ctx = netdev_priv(net);
>>>  	struct hv_device *device_obj = net_device_ctx->device_ctx;
>>> +	struct netvsc_device *nvdev;
>>> +	struct rndis_device *rdev;
>>>  	int ret = 0;
>>>
>>> +	netif_carrier_off(net);
>>> +
>>>  	/* Open up the device */
>>>  	ret = rndis_filter_open(device_obj);
>>>  	if (ret != 0) {
>>> @@ -99,6 +103,11 @@ static int netvsc_open(struct net_device *net)
>>>
>>>  	netif_start_queue(net);
>>>
>>> +	nvdev = hv_get_drvdata(device_obj);
>>> +	rdev = nvdev->extension;
>>> +	if (!rdev->link_state)
>>> +		netif_carrier_on(net);
>>> +
>> Maybe you can just schedule the work here and then you can drop the
>> rtnl_lock in netvsc_link_change() ?
> The rtnl_lock will still be necessary in the netvsc_link_change(), because 
> we want to prevent it getting wrong rdev pointer when netvsc_change_mtu
> is removing/adding rndis device.

Ok.
>>> +
>>> +	if (notify)
>>> +		netdev_notify_peers(net);
>>>  }
>>>
>> Looks like this forces arp_notify here. Is it expected?
> Yes, this is expected. It's required after live migration.
>
> Thanks,
> - Haiyang

Yes, this does not change the current behaviour. (arp_notify is
meaningless for netvsc).

Acked-by: Jason Wang <jasowang@redhat.com>

The patch is also needed for stable.

Thanks
>
> --
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Re: [PATCH net,v3] hyperv: Fix the carrier status setting

[David Miller]

From: Haiyang Zhang <haiyangz@microsoft.com>
Date: Wed, 12 Feb 2014 16:54:27 -0800

> Without this patch, the "cat /sys/class/net/ethN/operstate" shows
> "unknown", and "ethtool ethN" shows "Link detected: yes", when VM
> boots up with or without vNIC connected.
> 
> This patch fixed the problem.
> 
> Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
> Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>

Applied and queued up for -stable, thanks.