[net-next v4] vxlan: Notify drivers for listening UDP port changes

[net-next v4] vxlan: Notify drivers for listening UDP port changes

[Jeff Kirsher]

From: Joseph Gasparakis <joseph.gasparakis@intel.com>

This patch adds two more ndo ops: ndo_add_rx_vxlan_port() and
ndo_del_rx_vxlan_port().

Drivers can get notifications through the above functions about changes
of the UDP listening port of VXLAN. Also, when physical ports come up,
now they can call vxlan_get_rx_port() in order to obtain the port number(s)
of the existing VXLAN interface in case they already up before them.

This information about the listening UDP port would be used for VXLAN
related offloads.

A big thank you to John Fastabend (john.r.fastabend@intel.com) for his
input and his suggestions on this patch set.

CC: John Fastabend <john.r.fastabend@intel.com>
CC: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Joseph Gasparakis <joseph.gasparakis@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
---
 drivers/net/vxlan.c       | 68 ++++++++++++++++++++++++++++++++++++++++++++++-
 include/linux/netdevice.h | 19 +++++++++++++
 include/net/vxlan.h       |  1 +
 3 files changed, 87 insertions(+), 1 deletion(-)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index ebda3a1..0b62d82 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -558,6 +558,40 @@ static int vxlan_fdb_append(struct vxlan_fdb *f,
 	return 1;
 }
 
+/* Notify netdevs that UDP port started listening */
+static void vxlan_notify_add_rx_port(struct sock *sk)
+{
+	struct net_device *dev;
+	struct net *net = sock_net(sk);
+	sa_family_t sa_family = sk->sk_family;
+	u16 port = htons(inet_sk(sk)->inet_sport);
+
+	rcu_read_lock();
+	for_each_netdev_rcu(net, dev) {
+		if (dev->netdev_ops->ndo_add_vxlan_port)
+			dev->netdev_ops->ndo_add_vxlan_port(dev, sa_family,
+							    port);
+	}
+	rcu_read_unlock();
+}
+
+/* Notify netdevs that UDP port is no more listening */
+static void vxlan_notify_del_rx_port(struct sock *sk)
+{
+	struct net_device *dev;
+	struct net *net = sock_net(sk);
+	sa_family_t sa_family = sk->sk_family;
+	u16 port = htons(inet_sk(sk)->inet_sport);
+
+	rcu_read_lock();
+	for_each_netdev_rcu(net, dev) {
+		if (dev->netdev_ops->ndo_del_vxlan_port)
+			dev->netdev_ops->ndo_del_vxlan_port(dev, sa_family,
+							    port);
+	}
+	rcu_read_unlock();
+}
+
 /* Add new entry to forwarding table -- assumes lock held */
 static int vxlan_fdb_create(struct vxlan_dev *vxlan,
 			    const u8 *mac, union vxlan_addr *ip,
@@ -909,13 +943,16 @@ static void vxlan_sock_hold(struct vxlan_sock *vs)
 
 void vxlan_sock_release(struct vxlan_sock *vs)
 {
-	struct vxlan_net *vn = net_generic(sock_net(vs->sock->sk), vxlan_net_id);
+	struct sock *sk = vs->sock->sk;
+	struct net *net = sock_net(sk);
+	struct vxlan_net *vn = net_generic(net, vxlan_net_id);
 
 	if (!atomic_dec_and_test(&vs->refcnt))
 		return;
 
 	spin_lock(&vn->sock_lock);
 	hlist_del_rcu(&vs->hlist);
+	vxlan_notify_del_rx_port(sk);
 	spin_unlock(&vn->sock_lock);
 
 	queue_work(vxlan_wq, &vs->del_work);
@@ -1980,6 +2017,34 @@ static struct device_type vxlan_type = {
 	.name = "vxlan",
 };
 
+/* Calls the ndo_add_vxlan_port of the caller in order to
+ * supply the listening VXLAN udp ports.
+ */
+void vxlan_get_rx_port(struct net_device *dev)
+{
+	struct vxlan_sock *vs;
+	struct net *net = dev_net(dev);
+	struct vxlan_net *vn = net_generic(net, vxlan_net_id);
+	sa_family_t sa_family;
+	u16 port;
+	int i;
+
+	if (!dev || !dev->netdev_ops || !dev->netdev_ops->ndo_add_vxlan_port)
+		return;
+
+	spin_lock(&vn->sock_lock);
+	for (i = 0; i < PORT_HASH_SIZE; ++i) {
+		hlist_for_each_entry_rcu(vs, vs_head(net, i), hlist) {
+			port = htons(inet_sk(vs->sock->sk)->inet_sport);
+			sa_family = vs->sock->sk->sk_family;
+			dev->netdev_ops->ndo_add_vxlan_port(dev, sa_family,
+							    port);
+		}
+	}
+	spin_unlock(&vn->sock_lock);
+}
+EXPORT_SYMBOL_GPL(vxlan_get_rx_port);
+
 /* Initialize the device structure. */
 static void vxlan_setup(struct net_device *dev)
 {
@@ -2239,6 +2304,7 @@ static struct vxlan_sock *vxlan_socket_create(struct net *net, __be16 port,
 
 	spin_lock(&vn->sock_lock);
 	hlist_add_head_rcu(&vs->hlist, vs_head(net, port));
+	vxlan_notify_add_rx_port(sk);
 	spin_unlock(&vn->sock_lock);
 
 	/* Mark socket as an encapsulation socket. */
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 3ad49b8..8ed4ae9 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -948,6 +948,19 @@ struct netdev_phys_port_id {
  *	Called to get ID of physical port of this device. If driver does
  *	not implement this, it is assumed that the hw is not able to have
  *	multiple net devices on single physical port.
+ *
+ * void (*ndo_add_vxlan_port)(struct  net_device *dev,
+ *			      sa_family_t sa_family, __u16 port);
+ *	Called by vxlan to notiy a driver about the UDP port and socket
+ *	address family that vxlan is listnening to. It is called only when
+ *	a new port starts listening. The operation is protected by the
+ *	vxlan_net->sock_lock.
+ *
+ * void (*ndo_del_vxlan_port)(struct  net_device *dev,
+ *			      sa_family_t sa_family, __u16 port);
+ *	Called by vxlan to notify the driver about a UDP port and socket
+ *	address family that vxlan is not listening to anymore. The operation
+ *	is protected by the vxlan_net->sock_lock.
  */
 struct net_device_ops {
 	int			(*ndo_init)(struct net_device *dev);
@@ -1078,6 +1091,12 @@ struct net_device_ops {
 						      bool new_carrier);
 	int			(*ndo_get_phys_port_id)(struct net_device *dev,
 							struct netdev_phys_port_id *ppid);
+	void			(*ndo_add_vxlan_port)(struct  net_device *dev,
+						      sa_family_t sa_family,
+						      __u16 port);
+	void			(*ndo_del_vxlan_port)(struct  net_device *dev,
+						      sa_family_t sa_family,
+						      __u16 port);
 };
 
 /*
diff --git a/include/net/vxlan.h b/include/net/vxlan.h
index e09c40b..2d64d3c 100644
--- a/include/net/vxlan.h
+++ b/include/net/vxlan.h
@@ -36,4 +36,5 @@ int vxlan_xmit_skb(struct vxlan_sock *vs,
 
 __be16 vxlan_src_port(__u16 port_min, __u16 port_max, struct sk_buff *skb);
 
+void vxlan_get_rx_port(struct net_device *netdev);
 #endif
-- 
1.8.3.1

[net-next v4 RFC] ixgbe: Get and display the notifications from changes of the Rx vxlan UDP port

[Jeff Kirsher]

From: Joseph Gasparakis <joseph.gasparakis@intel.com>

This RFC patch showcases how drivers can use the changes in
"vxlan: Notify drivers for listening UDP port changes", and its
sole purpose is to help people test the changes introduced there.
This is not meant to be submitted for inclusion in the kernel.

CC: Don Skidmore <donald.c.skidmore@intel.com>
Signed-off-by: Joseph Gasparakis <joseph.gasparakis@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
---
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 7aba452..2d2c9b6 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -47,6 +47,9 @@
 #include <linux/if_bridge.h>
 #include <linux/prefetch.h>
 #include <scsi/fc/fc_fcoe.h>
+#ifdef CONFIG_VXLAN_MODULE
+#include <net/vxlan.h>
+#endif
 
 #include "ixgbe.h"
 #include "ixgbe_common.h"
@@ -5178,6 +5181,9 @@ static int ixgbe_open(struct net_device *netdev)
 
 	ixgbe_up_complete(adapter);
 
+#ifdef CONFIG_VXLAN_MODULE
+	vxlan_get_rx_port(netdev);
+#endif
 	return 0;
 
 err_set_queues:
@@ -7290,6 +7296,21 @@ static int ixgbe_ndo_bridge_getlink(struct sk_buff *skb, u32 pid, u32 seq,
 	return ndo_dflt_bridge_getlink(skb, pid, seq, dev, mode);
 }
 
+#ifdef CONFIG_VXLAN_MODULE
+static void ixgbe_add_vxlan_port(struct net_device *netdev,
+				 sa_family_t sa_family, __u16 port)
+{
+	netdev_info(netdev, ">>>>> Adding VXLAN port %d / protocol IPv%d\n",
+			     port, sa_family == AF_INET ? 4 : 6);
+}
+
+static void ixgbe_del_vxlan_port(struct net_device *netdev,
+				 sa_family_t sa_family, __u16 port)
+{
+	netdev_info(netdev, "<<<<< Removing VXLAN port %d / protocol IPv%d\n",
+			     port, sa_family == AF_INET ? 4 : 6);
+}
+#endif
 static const struct net_device_ops ixgbe_netdev_ops = {
 	.ndo_open		= ixgbe_open,
 	.ndo_stop		= ixgbe_close,
@@ -7334,6 +7355,10 @@ static const struct net_device_ops ixgbe_netdev_ops = {
 	.ndo_fdb_add		= ixgbe_ndo_fdb_add,
 	.ndo_bridge_setlink	= ixgbe_ndo_bridge_setlink,
 	.ndo_bridge_getlink	= ixgbe_ndo_bridge_getlink,
+#ifdef CONFIG_VXLAN_MODULE
+	.ndo_add_vxlan_port	= ixgbe_add_vxlan_port,
+	.ndo_del_vxlan_port	= ixgbe_del_vxlan_port,
+#endif
 };
 
 /**
-- 
1.8.3.1

Re: [net-next v4 RFC] ixgbe: Get and display the notifications from changes of the Rx vxlan UDP port

[Or Gerlitz]

On Wed, Sep 4, 2013 at 12:13 PM, Jeff Kirsher
<jeffrey.t.kirsher@intel.com> wrote:
> From: Joseph Gasparakis <joseph.gasparakis@intel.com>

> +#ifdef CONFIG_VXLAN_MODULE
> +static void ixgbe_add_vxlan_port(struct net_device *netdev,
> +                                sa_family_t sa_family, __u16 port)
> +{
> +       netdev_info(netdev, ">>>>> Adding VXLAN port %d / protocol IPv%d\n",
> +                            port, sa_family == AF_INET ? 4 : 6);
> +}
> +


any deep reason under which the low level driver needs to define these
ndo's under special config directive?

Or.

Re: [net-next v4] vxlan: Notify drivers for listening UDP port changes

[David Miller]

From: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Date: Wed,  4 Sep 2013 02:13:38 -0700

> From: Joseph Gasparakis <joseph.gasparakis@intel.com>
> 
> This patch adds two more ndo ops: ndo_add_rx_vxlan_port() and
> ndo_del_rx_vxlan_port().
> 
> Drivers can get notifications through the above functions about changes
> of the UDP listening port of VXLAN. Also, when physical ports come up,
> now they can call vxlan_get_rx_port() in order to obtain the port number(s)
> of the existing VXLAN interface in case they already up before them.
> 
> This information about the listening UDP port would be used for VXLAN
> related offloads.
> 
> A big thank you to John Fastabend (john.r.fastabend@intel.com) for his
> input and his suggestions on this patch set.
> 
> CC: John Fastabend <john.r.fastabend@intel.com>
> CC: Stephen Hemminger <stephen@networkplumber.org>
> Signed-off-by: Joseph Gasparakis <joseph.gasparakis@intel.com>
> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Applied.

Re: [net-next v4] vxlan: Notify drivers for listening UDP port changes

[Daniel Borkmann]

On 09/04/2013 11:13 AM, Jeff Kirsher wrote:
> From: Joseph Gasparakis <joseph.gasparakis@intel.com>
>
> This patch adds two more ndo ops: ndo_add_rx_vxlan_port() and
> ndo_del_rx_vxlan_port().
>
> Drivers can get notifications through the above functions about changes
> of the UDP listening port of VXLAN. Also, when physical ports come up,
> now they can call vxlan_get_rx_port() in order to obtain the port number(s)
> of the existing VXLAN interface in case they already up before them.
>
> This information about the listening UDP port would be used for VXLAN
> related offloads.
>
> A big thank you to John Fastabend (john.r.fastabend@intel.com) for his
> input and his suggestions on this patch set.
>
> CC: John Fastabend <john.r.fastabend@intel.com>
> CC: Stephen Hemminger <stephen@networkplumber.org>
> Signed-off-by: Joseph Gasparakis <joseph.gasparakis@intel.com>
> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
> ---
>   drivers/net/vxlan.c       | 68 ++++++++++++++++++++++++++++++++++++++++++++++-
>   include/linux/netdevice.h | 19 +++++++++++++
>   include/net/vxlan.h       |  1 +
>   3 files changed, 87 insertions(+), 1 deletion(-)
[...]
> +/* Calls the ndo_add_vxlan_port of the caller in order to
> + * supply the listening VXLAN udp ports.
> + */
> +void vxlan_get_rx_port(struct net_device *dev)
> +{
> +	struct vxlan_sock *vs;
> +	struct net *net = dev_net(dev);
> +	struct vxlan_net *vn = net_generic(net, vxlan_net_id);
> +	sa_family_t sa_family;
> +	u16 port;
> +	int i;
> +
> +	if (!dev || !dev->netdev_ops || !dev->netdev_ops->ndo_add_vxlan_port)
> +		return;

Here, either parts of this if statement are unnecessary, or in case they are
necessary then vars 'net' and 'vn' should have been assigned after that I think
as we would first get an offset and then dereference it before actually checking
if dev is NULL.

> +	spin_lock(&vn->sock_lock);
> +	for (i = 0; i < PORT_HASH_SIZE; ++i) {
> +		hlist_for_each_entry_rcu(vs, vs_head(net, i), hlist) {
> +			port = htons(inet_sk(vs->sock->sk)->inet_sport);
> +			sa_family = vs->sock->sk->sk_family;
> +			dev->netdev_ops->ndo_add_vxlan_port(dev, sa_family,
> +							    port);
> +		}
> +	}
> +	spin_unlock(&vn->sock_lock);
> +}
> +EXPORT_SYMBOL_GPL(vxlan_get_rx_port);

Re: [net-next v4] vxlan: Notify drivers for listening UDP port changes

[Joseph Gasparakis]

On Fri, 6 Sep 2013, Daniel Borkmann wrote:

> On 09/04/2013 11:13 AM, Jeff Kirsher wrote:
> > From: Joseph Gasparakis <joseph.gasparakis@intel.com>
> > 
> > This patch adds two more ndo ops: ndo_add_rx_vxlan_port() and
> > ndo_del_rx_vxlan_port().
> > 
> > Drivers can get notifications through the above functions about changes
> > of the UDP listening port of VXLAN. Also, when physical ports come up,
> > now they can call vxlan_get_rx_port() in order to obtain the port number(s)
> > of the existing VXLAN interface in case they already up before them.
> > 
> > This information about the listening UDP port would be used for VXLAN
> > related offloads.
> > 
> > A big thank you to John Fastabend (john.r.fastabend@intel.com) for his
> > input and his suggestions on this patch set.
> > 
> > CC: John Fastabend <john.r.fastabend@intel.com>
> > CC: Stephen Hemminger <stephen@networkplumber.org>
> > Signed-off-by: Joseph Gasparakis <joseph.gasparakis@intel.com>
> > Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
> > ---
> >   drivers/net/vxlan.c       | 68
> > ++++++++++++++++++++++++++++++++++++++++++++++-
> >   include/linux/netdevice.h | 19 +++++++++++++
> >   include/net/vxlan.h       |  1 +
> >   3 files changed, 87 insertions(+), 1 deletion(-)
> [...]
> > +/* Calls the ndo_add_vxlan_port of the caller in order to
> > + * supply the listening VXLAN udp ports.
> > + */
> > +void vxlan_get_rx_port(struct net_device *dev)
> > +{
> > +	struct vxlan_sock *vs;
> > +	struct net *net = dev_net(dev);
> > +	struct vxlan_net *vn = net_generic(net, vxlan_net_id);
> > +	sa_family_t sa_family;
> > +	u16 port;
> > +	int i;
> > +
> > +	if (!dev || !dev->netdev_ops || !dev->netdev_ops->ndo_add_vxlan_port)
> > +		return;
> 
> Here, either parts of this if statement are unnecessary, or in case they are
> necessary then vars 'net' and 'vn' should have been assigned after that I
> think
> as we would first get an offset and then dereference it before actually
> checking
> if dev is NULL.

That is correct, I started assuming dev will be a valid pointer, but then 
I thought I shouldn't trust the caller, so I ended up with this. In fact I 
have some upcoming sparse fixes too, so I will incorporate all this in one 
patch. For this particular comment I will be checking dev first and 
assigning net and vn after that.

> 
> > +	spin_lock(&vn->sock_lock);
> > +	for (i = 0; i < PORT_HASH_SIZE; ++i) {
> > +		hlist_for_each_entry_rcu(vs, vs_head(net, i), hlist) {
> > +			port = htons(inet_sk(vs->sock->sk)->inet_sport);
> > +			sa_family = vs->sock->sk->sk_family;
> > +			dev->netdev_ops->ndo_add_vxlan_port(dev, sa_family,
> > +							    port);
> > +		}
> > +	}
> > +	spin_unlock(&vn->sock_lock);
> > +}
> > +EXPORT_SYMBOL_GPL(vxlan_get_rx_port);
> 

Re: [net-next v4] vxlan: Notify drivers for listening UDP port changes

[Stephen Hemminger]

On Fri, 6 Sep 2013 16:42:26 -0700 (PDT)
Joseph Gasparakis <joseph.gasparakis@intel.com> wrote:

> That is correct, I started assuming dev will be a valid pointer, but then 
> I thought I shouldn't trust the caller, so I ended up with this. In fact I 
> have some upcoming sparse fixes too, so I will incorporate all this in one 
> patch. For this particular comment I will be checking dev first and 
> assigning net and vn after that.

This is the kernel, audit the callers. We don't add random null
pointer checks because that is worse. It creates random error paths
to validate.

Re: [net-next v4] vxlan: Notify drivers for listening UDP port changes

[Joseph Gasparakis]

On Fri, 6 Sep 2013, Stephen Hemminger wrote:

> On Fri, 6 Sep 2013 16:42:26 -0700 (PDT)
> Joseph Gasparakis <joseph.gasparakis@intel.com> wrote:
> 
> > That is correct, I started assuming dev will be a valid pointer, but then 
> > I thought I shouldn't trust the caller, so I ended up with this. In fact I 
> > have some upcoming sparse fixes too, so I will incorporate all this in one 
> > patch. For this particular comment I will be checking dev first and 
> > assigning net and vn after that.
> 
> This is the kernel, audit the callers. We don't add random null
> pointer checks because that is worse. It creates random error paths
> to validate.
> 

Will do. Thanks!