This commit implements datagram support for virtio/vsock by teaching
virtio to use the general virtio transport ->dgram_addr_init() function
and implementation a new version of ->dgram_allow().

Additionally, it drops virtio_transport_dgram_allow() as an exported
symbol because it is no longer used in other transports.

Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com>
---
 include/linux/virtio_vsock.h            |  1 -
 net/vmw_vsock/virtio_transport.c        | 24 +++++++++++++++++++++++-
 net/vmw_vsock/virtio_transport_common.c |  6 ------
 3 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h
index b3856b8a42b3..d0a4f08b12c1 100644
--- a/include/linux/virtio_vsock.h
+++ b/include/linux/virtio_vsock.h
@@ -211,7 +211,6 @@ void virtio_transport_notify_buffer_size(struct vsock_sock *vsk, u64 *val);
 u64 virtio_transport_stream_rcvhiwat(struct vsock_sock *vsk);
 bool virtio_transport_stream_is_active(struct vsock_sock *vsk);
 bool virtio_transport_stream_allow(u32 cid, u32 port);
-bool virtio_transport_dgram_allow(u32 cid, u32 port);
 void virtio_transport_dgram_addr_init(struct sk_buff *skb,
 				      struct sockaddr_vm *addr);
 
diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
index ac2126c7dac5..713718861bd4 100644
--- a/net/vmw_vsock/virtio_transport.c
+++ b/net/vmw_vsock/virtio_transport.c
@@ -63,6 +63,7 @@ struct virtio_vsock {
 
 	u32 guest_cid;
 	bool seqpacket_allow;
+	bool dgram_allow;
 };
 
 static u32 virtio_transport_get_local_cid(void)
@@ -413,6 +414,7 @@ static void virtio_vsock_rx_done(struct virtqueue *vq)
 	queue_work(virtio_vsock_workqueue, &vsock->rx_work);
 }
 
+static bool virtio_transport_dgram_allow(u32 cid, u32 port);
 static bool virtio_transport_seqpacket_allow(u32 remote_cid);
 
 static struct virtio_transport virtio_transport = {
@@ -430,6 +432,7 @@ static struct virtio_transport virtio_transport = {
 
 		.dgram_enqueue            = virtio_transport_dgram_enqueue,
 		.dgram_allow              = virtio_transport_dgram_allow,
+		.dgram_addr_init          = virtio_transport_dgram_addr_init,
 
 		.stream_dequeue           = virtio_transport_stream_dequeue,
 		.stream_enqueue           = virtio_transport_stream_enqueue,
@@ -462,6 +465,21 @@ static struct virtio_transport virtio_transport = {
 	.send_pkt = virtio_transport_send_pkt,
 };
 
+static bool virtio_transport_dgram_allow(u32 cid, u32 port)
+{
+	struct virtio_vsock *vsock;
+	bool dgram_allow;
+
+	dgram_allow = false;
+	rcu_read_lock();
+	vsock = rcu_dereference(the_virtio_vsock);
+	if (vsock)
+		dgram_allow = vsock->dgram_allow;
+	rcu_read_unlock();
+
+	return dgram_allow;
+}
+
 static bool virtio_transport_seqpacket_allow(u32 remote_cid)
 {
 	struct virtio_vsock *vsock;
@@ -655,6 +673,9 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
 	if (virtio_has_feature(vdev, VIRTIO_VSOCK_F_SEQPACKET))
 		vsock->seqpacket_allow = true;
 
+	if (virtio_has_feature(vdev, VIRTIO_VSOCK_F_DGRAM))
+		vsock->dgram_allow = true;
+
 	vdev->priv = vsock;
 
 	ret = virtio_vsock_vqs_init(vsock);
@@ -747,7 +768,8 @@ static struct virtio_device_id id_table[] = {
 };
 
 static unsigned int features[] = {
-	VIRTIO_VSOCK_F_SEQPACKET
+	VIRTIO_VSOCK_F_SEQPACKET,
+	VIRTIO_VSOCK_F_DGRAM
 };
 
 static struct virtio_driver virtio_vsock_driver = {
diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
index 96118e258097..77898f5325cd 100644
--- a/net/vmw_vsock/virtio_transport_common.c
+++ b/net/vmw_vsock/virtio_transport_common.c
@@ -783,12 +783,6 @@ bool virtio_transport_stream_allow(u32 cid, u32 port)
 }
 EXPORT_SYMBOL_GPL(virtio_transport_stream_allow);
 
-bool virtio_transport_dgram_allow(u32 cid, u32 port)
-{
-	return false;
-}
-EXPORT_SYMBOL_GPL(virtio_transport_dgram_allow);
-
 int virtio_transport_connect(struct vsock_sock *vsk)
 {
 	struct virtio_vsock_pkt_info info = {

-- 
2.30.2

On 19.07.2023 03:50, Bobby Eshleman wrote:
> This commit implements datagram support for virtio/vsock by teaching
> virtio to use the general virtio transport ->dgram_addr_init() function
> and implementation a new version of ->dgram_allow().
> 
> Additionally, it drops virtio_transport_dgram_allow() as an exported
> symbol because it is no longer used in other transports.
> 
> Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com>
> ---
>  include/linux/virtio_vsock.h            |  1 -
>  net/vmw_vsock/virtio_transport.c        | 24 +++++++++++++++++++++++-
>  net/vmw_vsock/virtio_transport_common.c |  6 ------
>  3 files changed, 23 insertions(+), 8 deletions(-)
> 
> diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h
> index b3856b8a42b3..d0a4f08b12c1 100644
> --- a/include/linux/virtio_vsock.h
> +++ b/include/linux/virtio_vsock.h
> @@ -211,7 +211,6 @@ void virtio_transport_notify_buffer_size(struct vsock_sock *vsk, u64 *val);
>  u64 virtio_transport_stream_rcvhiwat(struct vsock_sock *vsk);
>  bool virtio_transport_stream_is_active(struct vsock_sock *vsk);
>  bool virtio_transport_stream_allow(u32 cid, u32 port);
> -bool virtio_transport_dgram_allow(u32 cid, u32 port);
>  void virtio_transport_dgram_addr_init(struct sk_buff *skb,
>  				      struct sockaddr_vm *addr);
>  
> diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
> index ac2126c7dac5..713718861bd4 100644
> --- a/net/vmw_vsock/virtio_transport.c
> +++ b/net/vmw_vsock/virtio_transport.c
> @@ -63,6 +63,7 @@ struct virtio_vsock {
>  
>  	u32 guest_cid;
>  	bool seqpacket_allow;
> +	bool dgram_allow;
>  };
>  
>  static u32 virtio_transport_get_local_cid(void)
> @@ -413,6 +414,7 @@ static void virtio_vsock_rx_done(struct virtqueue *vq)
>  	queue_work(virtio_vsock_workqueue, &vsock->rx_work);
>  }
>  
> +static bool virtio_transport_dgram_allow(u32 cid, u32 port);

May be add body here? Without prototyping? Same for loopback and vhost.

>  static bool virtio_transport_seqpacket_allow(u32 remote_cid);
>  
>  static struct virtio_transport virtio_transport = {
> @@ -430,6 +432,7 @@ static struct virtio_transport virtio_transport = {
>  
>  		.dgram_enqueue            = virtio_transport_dgram_enqueue,
>  		.dgram_allow              = virtio_transport_dgram_allow,
> +		.dgram_addr_init          = virtio_transport_dgram_addr_init,
>  
>  		.stream_dequeue           = virtio_transport_stream_dequeue,
>  		.stream_enqueue           = virtio_transport_stream_enqueue,
> @@ -462,6 +465,21 @@ static struct virtio_transport virtio_transport = {
>  	.send_pkt = virtio_transport_send_pkt,
>  };
>  
> +static bool virtio_transport_dgram_allow(u32 cid, u32 port)
> +{
> +	struct virtio_vsock *vsock;
> +	bool dgram_allow;
> +
> +	dgram_allow = false;
> +	rcu_read_lock();
> +	vsock = rcu_dereference(the_virtio_vsock);
> +	if (vsock)
> +		dgram_allow = vsock->dgram_allow;
> +	rcu_read_unlock();
> +
> +	return dgram_allow;
> +}
> +
>  static bool virtio_transport_seqpacket_allow(u32 remote_cid)
>  {
>  	struct virtio_vsock *vsock;
> @@ -655,6 +673,9 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
>  	if (virtio_has_feature(vdev, VIRTIO_VSOCK_F_SEQPACKET))
>  		vsock->seqpacket_allow = true;
>  
> +	if (virtio_has_feature(vdev, VIRTIO_VSOCK_F_DGRAM))
> +		vsock->dgram_allow = true;
> +
>  	vdev->priv = vsock;
>  
>  	ret = virtio_vsock_vqs_init(vsock);
> @@ -747,7 +768,8 @@ static struct virtio_device_id id_table[] = {
>  };
>  
>  static unsigned int features[] = {
> -	VIRTIO_VSOCK_F_SEQPACKET
> +	VIRTIO_VSOCK_F_SEQPACKET,
> +	VIRTIO_VSOCK_F_DGRAM
>  };
>  
>  static struct virtio_driver virtio_vsock_driver = {
> diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
> index 96118e258097..77898f5325cd 100644
> --- a/net/vmw_vsock/virtio_transport_common.c
> +++ b/net/vmw_vsock/virtio_transport_common.c
> @@ -783,12 +783,6 @@ bool virtio_transport_stream_allow(u32 cid, u32 port)
>  }
>  EXPORT_SYMBOL_GPL(virtio_transport_stream_allow);
>  
> -bool virtio_transport_dgram_allow(u32 cid, u32 port)
> -{
> -	return false;
> -}
> -EXPORT_SYMBOL_GPL(virtio_transport_dgram_allow);
> -
>  int virtio_transport_connect(struct vsock_sock *vsk)
>  {
>  	struct virtio_vsock_pkt_info info = {
> 

Thanks, Arseniy

On Sat, Jul 22, 2023 at 11:45:29AM +0300, Arseniy Krasnov wrote:
> 
> 
> On 19.07.2023 03:50, Bobby Eshleman wrote:
> > This commit implements datagram support for virtio/vsock by teaching
> > virtio to use the general virtio transport ->dgram_addr_init() function
> > and implementation a new version of ->dgram_allow().
> > 
> > Additionally, it drops virtio_transport_dgram_allow() as an exported
> > symbol because it is no longer used in other transports.
> > 
> > Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com>
> > ---
> >  include/linux/virtio_vsock.h            |  1 -
> >  net/vmw_vsock/virtio_transport.c        | 24 +++++++++++++++++++++++-
> >  net/vmw_vsock/virtio_transport_common.c |  6 ------
> >  3 files changed, 23 insertions(+), 8 deletions(-)
> > 
> > diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h
> > index b3856b8a42b3..d0a4f08b12c1 100644
> > --- a/include/linux/virtio_vsock.h
> > +++ b/include/linux/virtio_vsock.h
> > @@ -211,7 +211,6 @@ void virtio_transport_notify_buffer_size(struct vsock_sock *vsk, u64 *val);
> >  u64 virtio_transport_stream_rcvhiwat(struct vsock_sock *vsk);
> >  bool virtio_transport_stream_is_active(struct vsock_sock *vsk);
> >  bool virtio_transport_stream_allow(u32 cid, u32 port);
> > -bool virtio_transport_dgram_allow(u32 cid, u32 port);
> >  void virtio_transport_dgram_addr_init(struct sk_buff *skb,
> >  				      struct sockaddr_vm *addr);
> >  
> > diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
> > index ac2126c7dac5..713718861bd4 100644
> > --- a/net/vmw_vsock/virtio_transport.c
> > +++ b/net/vmw_vsock/virtio_transport.c
> > @@ -63,6 +63,7 @@ struct virtio_vsock {
> >  
> >  	u32 guest_cid;
> >  	bool seqpacket_allow;
> > +	bool dgram_allow;
> >  };
> >  
> >  static u32 virtio_transport_get_local_cid(void)
> > @@ -413,6 +414,7 @@ static void virtio_vsock_rx_done(struct virtqueue *vq)
> >  	queue_work(virtio_vsock_workqueue, &vsock->rx_work);
> >  }
> >  
> > +static bool virtio_transport_dgram_allow(u32 cid, u32 port);
> 
> May be add body here? Without prototyping? Same for loopback and vhost.
> 

Sounds okay with me, but this seems to go against the pattern
established by seqpacket. Any reason why?

> >  static bool virtio_transport_seqpacket_allow(u32 remote_cid);
> >  
> >  static struct virtio_transport virtio_transport = {
> > @@ -430,6 +432,7 @@ static struct virtio_transport virtio_transport = {
> >  
> >  		.dgram_enqueue            = virtio_transport_dgram_enqueue,
> >  		.dgram_allow              = virtio_transport_dgram_allow,
> > +		.dgram_addr_init          = virtio_transport_dgram_addr_init,
> >  
> >  		.stream_dequeue           = virtio_transport_stream_dequeue,
> >  		.stream_enqueue           = virtio_transport_stream_enqueue,
> > @@ -462,6 +465,21 @@ static struct virtio_transport virtio_transport = {
> >  	.send_pkt = virtio_transport_send_pkt,
> >  };
> >  
> > +static bool virtio_transport_dgram_allow(u32 cid, u32 port)
> > +{
> > +	struct virtio_vsock *vsock;
> > +	bool dgram_allow;
> > +
> > +	dgram_allow = false;
> > +	rcu_read_lock();
> > +	vsock = rcu_dereference(the_virtio_vsock);
> > +	if (vsock)
> > +		dgram_allow = vsock->dgram_allow;
> > +	rcu_read_unlock();
> > +
> > +	return dgram_allow;
> > +}
> > +
> >  static bool virtio_transport_seqpacket_allow(u32 remote_cid)
> >  {
> >  	struct virtio_vsock *vsock;
> > @@ -655,6 +673,9 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
> >  	if (virtio_has_feature(vdev, VIRTIO_VSOCK_F_SEQPACKET))
> >  		vsock->seqpacket_allow = true;
> >  
> > +	if (virtio_has_feature(vdev, VIRTIO_VSOCK_F_DGRAM))
> > +		vsock->dgram_allow = true;
> > +
> >  	vdev->priv = vsock;
> >  
> >  	ret = virtio_vsock_vqs_init(vsock);
> > @@ -747,7 +768,8 @@ static struct virtio_device_id id_table[] = {
> >  };
> >  
> >  static unsigned int features[] = {
> > -	VIRTIO_VSOCK_F_SEQPACKET
> > +	VIRTIO_VSOCK_F_SEQPACKET,
> > +	VIRTIO_VSOCK_F_DGRAM
> >  };
> >  
> >  static struct virtio_driver virtio_vsock_driver = {
> > diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
> > index 96118e258097..77898f5325cd 100644
> > --- a/net/vmw_vsock/virtio_transport_common.c
> > +++ b/net/vmw_vsock/virtio_transport_common.c
> > @@ -783,12 +783,6 @@ bool virtio_transport_stream_allow(u32 cid, u32 port)
> >  }
> >  EXPORT_SYMBOL_GPL(virtio_transport_stream_allow);
> >  
> > -bool virtio_transport_dgram_allow(u32 cid, u32 port)
> > -{
> > -	return false;
> > -}
> > -EXPORT_SYMBOL_GPL(virtio_transport_dgram_allow);
> > -
> >  int virtio_transport_connect(struct vsock_sock *vsk)
> >  {
> >  	struct virtio_vsock_pkt_info info = {
> > 
> 
> Thanks, Arseniy

Thanks,
Bobby

On 26.07.2023 20:58, Bobby Eshleman wrote:
> On Sat, Jul 22, 2023 at 11:45:29AM +0300, Arseniy Krasnov wrote:
>>
>>
>> On 19.07.2023 03:50, Bobby Eshleman wrote:
>>> This commit implements datagram support for virtio/vsock by teaching
>>> virtio to use the general virtio transport ->dgram_addr_init() function
>>> and implementation a new version of ->dgram_allow().
>>>
>>> Additionally, it drops virtio_transport_dgram_allow() as an exported
>>> symbol because it is no longer used in other transports.
>>>
>>> Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com>
>>> ---
>>>  include/linux/virtio_vsock.h            |  1 -
>>>  net/vmw_vsock/virtio_transport.c        | 24 +++++++++++++++++++++++-
>>>  net/vmw_vsock/virtio_transport_common.c |  6 ------
>>>  3 files changed, 23 insertions(+), 8 deletions(-)
>>>
>>> diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h
>>> index b3856b8a42b3..d0a4f08b12c1 100644
>>> --- a/include/linux/virtio_vsock.h
>>> +++ b/include/linux/virtio_vsock.h
>>> @@ -211,7 +211,6 @@ void virtio_transport_notify_buffer_size(struct vsock_sock *vsk, u64 *val);
>>>  u64 virtio_transport_stream_rcvhiwat(struct vsock_sock *vsk);
>>>  bool virtio_transport_stream_is_active(struct vsock_sock *vsk);
>>>  bool virtio_transport_stream_allow(u32 cid, u32 port);
>>> -bool virtio_transport_dgram_allow(u32 cid, u32 port);
>>>  void virtio_transport_dgram_addr_init(struct sk_buff *skb,
>>>  				      struct sockaddr_vm *addr);
>>>  
>>> diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
>>> index ac2126c7dac5..713718861bd4 100644
>>> --- a/net/vmw_vsock/virtio_transport.c
>>> +++ b/net/vmw_vsock/virtio_transport.c
>>> @@ -63,6 +63,7 @@ struct virtio_vsock {
>>>  
>>>  	u32 guest_cid;
>>>  	bool seqpacket_allow;
>>> +	bool dgram_allow;
>>>  };
>>>  
>>>  static u32 virtio_transport_get_local_cid(void)
>>> @@ -413,6 +414,7 @@ static void virtio_vsock_rx_done(struct virtqueue *vq)
>>>  	queue_work(virtio_vsock_workqueue, &vsock->rx_work);
>>>  }
>>>  
>>> +static bool virtio_transport_dgram_allow(u32 cid, u32 port);
>>
>> May be add body here? Without prototyping? Same for loopback and vhost.
>>
> 
> Sounds okay with me, but this seems to go against the pattern
> established by seqpacket. Any reason why?

Stefano Garzarella <sgarzare@redhat.com> commented my patch with the same approach:

https://lore.kernel.org/netdev/lex6l5suez7azhirt22lidndtjomkbagfbpvvi5p7c2t7klzas@4l2qly7at37c/

Thanks, Arseniy


> 
>>>  static bool virtio_transport_seqpacket_allow(u32 remote_cid);
>>>  
>>>  static struct virtio_transport virtio_transport = {
>>> @@ -430,6 +432,7 @@ static struct virtio_transport virtio_transport = {
>>>  
>>>  		.dgram_enqueue            = virtio_transport_dgram_enqueue,
>>>  		.dgram_allow              = virtio_transport_dgram_allow,
>>> +		.dgram_addr_init          = virtio_transport_dgram_addr_init,
>>>  
>>>  		.stream_dequeue           = virtio_transport_stream_dequeue,
>>>  		.stream_enqueue           = virtio_transport_stream_enqueue,
>>> @@ -462,6 +465,21 @@ static struct virtio_transport virtio_transport = {
>>>  	.send_pkt = virtio_transport_send_pkt,
>>>  };
>>>  
>>> +static bool virtio_transport_dgram_allow(u32 cid, u32 port)
>>> +{
>>> +	struct virtio_vsock *vsock;
>>> +	bool dgram_allow;
>>> +
>>> +	dgram_allow = false;
>>> +	rcu_read_lock();
>>> +	vsock = rcu_dereference(the_virtio_vsock);
>>> +	if (vsock)
>>> +		dgram_allow = vsock->dgram_allow;
>>> +	rcu_read_unlock();
>>> +
>>> +	return dgram_allow;
>>> +}
>>> +
>>>  static bool virtio_transport_seqpacket_allow(u32 remote_cid)
>>>  {
>>>  	struct virtio_vsock *vsock;
>>> @@ -655,6 +673,9 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
>>>  	if (virtio_has_feature(vdev, VIRTIO_VSOCK_F_SEQPACKET))
>>>  		vsock->seqpacket_allow = true;
>>>  
>>> +	if (virtio_has_feature(vdev, VIRTIO_VSOCK_F_DGRAM))
>>> +		vsock->dgram_allow = true;
>>> +
>>>  	vdev->priv = vsock;
>>>  
>>>  	ret = virtio_vsock_vqs_init(vsock);
>>> @@ -747,7 +768,8 @@ static struct virtio_device_id id_table[] = {
>>>  };
>>>  
>>>  static unsigned int features[] = {
>>> -	VIRTIO_VSOCK_F_SEQPACKET
>>> +	VIRTIO_VSOCK_F_SEQPACKET,
>>> +	VIRTIO_VSOCK_F_DGRAM
>>>  };
>>>  
>>>  static struct virtio_driver virtio_vsock_driver = {
>>> diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
>>> index 96118e258097..77898f5325cd 100644
>>> --- a/net/vmw_vsock/virtio_transport_common.c
>>> +++ b/net/vmw_vsock/virtio_transport_common.c
>>> @@ -783,12 +783,6 @@ bool virtio_transport_stream_allow(u32 cid, u32 port)
>>>  }
>>>  EXPORT_SYMBOL_GPL(virtio_transport_stream_allow);
>>>  
>>> -bool virtio_transport_dgram_allow(u32 cid, u32 port)
>>> -{
>>> -	return false;
>>> -}
>>> -EXPORT_SYMBOL_GPL(virtio_transport_dgram_allow);
>>> -
>>>  int virtio_transport_connect(struct vsock_sock *vsk)
>>>  {
>>>  	struct virtio_vsock_pkt_info info = {
>>>
>>
>> Thanks, Arseniy
> 
> Thanks,
> Bobby

On Thu, Jul 27, 2023 at 11:09:21AM +0300, Arseniy Krasnov wrote:
> 
> 
> On 26.07.2023 20:58, Bobby Eshleman wrote:
> > On Sat, Jul 22, 2023 at 11:45:29AM +0300, Arseniy Krasnov wrote:
> >>
> >>
> >> On 19.07.2023 03:50, Bobby Eshleman wrote:
> >>> This commit implements datagram support for virtio/vsock by teaching
> >>> virtio to use the general virtio transport ->dgram_addr_init() function
> >>> and implementation a new version of ->dgram_allow().
> >>>
> >>> Additionally, it drops virtio_transport_dgram_allow() as an exported
> >>> symbol because it is no longer used in other transports.
> >>>
> >>> Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com>
> >>> ---
> >>>  include/linux/virtio_vsock.h            |  1 -
> >>>  net/vmw_vsock/virtio_transport.c        | 24 +++++++++++++++++++++++-
> >>>  net/vmw_vsock/virtio_transport_common.c |  6 ------
> >>>  3 files changed, 23 insertions(+), 8 deletions(-)
> >>>
> >>> diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h
> >>> index b3856b8a42b3..d0a4f08b12c1 100644
> >>> --- a/include/linux/virtio_vsock.h
> >>> +++ b/include/linux/virtio_vsock.h
> >>> @@ -211,7 +211,6 @@ void virtio_transport_notify_buffer_size(struct vsock_sock *vsk, u64 *val);
> >>>  u64 virtio_transport_stream_rcvhiwat(struct vsock_sock *vsk);
> >>>  bool virtio_transport_stream_is_active(struct vsock_sock *vsk);
> >>>  bool virtio_transport_stream_allow(u32 cid, u32 port);
> >>> -bool virtio_transport_dgram_allow(u32 cid, u32 port);
> >>>  void virtio_transport_dgram_addr_init(struct sk_buff *skb,
> >>>  				      struct sockaddr_vm *addr);
> >>>  
> >>> diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
> >>> index ac2126c7dac5..713718861bd4 100644
> >>> --- a/net/vmw_vsock/virtio_transport.c
> >>> +++ b/net/vmw_vsock/virtio_transport.c
> >>> @@ -63,6 +63,7 @@ struct virtio_vsock {
> >>>  
> >>>  	u32 guest_cid;
> >>>  	bool seqpacket_allow;
> >>> +	bool dgram_allow;
> >>>  };
> >>>  
> >>>  static u32 virtio_transport_get_local_cid(void)
> >>> @@ -413,6 +414,7 @@ static void virtio_vsock_rx_done(struct virtqueue *vq)
> >>>  	queue_work(virtio_vsock_workqueue, &vsock->rx_work);
> >>>  }
> >>>  
> >>> +static bool virtio_transport_dgram_allow(u32 cid, u32 port);
> >>
> >> May be add body here? Without prototyping? Same for loopback and vhost.
> >>
> > 
> > Sounds okay with me, but this seems to go against the pattern
> > established by seqpacket. Any reason why?
> 
> Stefano Garzarella <sgarzare@redhat.com> commented my patch with the same approach:
> 
> https://lore.kernel.org/netdev/lex6l5suez7azhirt22lidndtjomkbagfbpvvi5p7c2t7klzas@4l2qly7at37c/
> 
> Thanks, Arseniy
> 

Gotcha, sounds good.

Thanks,
Bobby
> 
> > 
> >>>  static bool virtio_transport_seqpacket_allow(u32 remote_cid);
> >>>  
> >>>  static struct virtio_transport virtio_transport = {
> >>> @@ -430,6 +432,7 @@ static struct virtio_transport virtio_transport = {
> >>>  
> >>>  		.dgram_enqueue            = virtio_transport_dgram_enqueue,
> >>>  		.dgram_allow              = virtio_transport_dgram_allow,
> >>> +		.dgram_addr_init          = virtio_transport_dgram_addr_init,
> >>>  
> >>>  		.stream_dequeue           = virtio_transport_stream_dequeue,
> >>>  		.stream_enqueue           = virtio_transport_stream_enqueue,
> >>> @@ -462,6 +465,21 @@ static struct virtio_transport virtio_transport = {
> >>>  	.send_pkt = virtio_transport_send_pkt,
> >>>  };
> >>>  
> >>> +static bool virtio_transport_dgram_allow(u32 cid, u32 port)
> >>> +{
> >>> +	struct virtio_vsock *vsock;
> >>> +	bool dgram_allow;
> >>> +
> >>> +	dgram_allow = false;
> >>> +	rcu_read_lock();
> >>> +	vsock = rcu_dereference(the_virtio_vsock);
> >>> +	if (vsock)
> >>> +		dgram_allow = vsock->dgram_allow;
> >>> +	rcu_read_unlock();
> >>> +
> >>> +	return dgram_allow;
> >>> +}
> >>> +
> >>>  static bool virtio_transport_seqpacket_allow(u32 remote_cid)
> >>>  {
> >>>  	struct virtio_vsock *vsock;
> >>> @@ -655,6 +673,9 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
> >>>  	if (virtio_has_feature(vdev, VIRTIO_VSOCK_F_SEQPACKET))
> >>>  		vsock->seqpacket_allow = true;
> >>>  
> >>> +	if (virtio_has_feature(vdev, VIRTIO_VSOCK_F_DGRAM))
> >>> +		vsock->dgram_allow = true;
> >>> +
> >>>  	vdev->priv = vsock;
> >>>  
> >>>  	ret = virtio_vsock_vqs_init(vsock);
> >>> @@ -747,7 +768,8 @@ static struct virtio_device_id id_table[] = {
> >>>  };
> >>>  
> >>>  static unsigned int features[] = {
> >>> -	VIRTIO_VSOCK_F_SEQPACKET
> >>> +	VIRTIO_VSOCK_F_SEQPACKET,
> >>> +	VIRTIO_VSOCK_F_DGRAM
> >>>  };
> >>>  
> >>>  static struct virtio_driver virtio_vsock_driver = {
> >>> diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
> >>> index 96118e258097..77898f5325cd 100644
> >>> --- a/net/vmw_vsock/virtio_transport_common.c
> >>> +++ b/net/vmw_vsock/virtio_transport_common.c
> >>> @@ -783,12 +783,6 @@ bool virtio_transport_stream_allow(u32 cid, u32 port)
> >>>  }
> >>>  EXPORT_SYMBOL_GPL(virtio_transport_stream_allow);
> >>>  
> >>> -bool virtio_transport_dgram_allow(u32 cid, u32 port)
> >>> -{
> >>> -	return false;
> >>> -}
> >>> -EXPORT_SYMBOL_GPL(virtio_transport_dgram_allow);
> >>> -
> >>>  int virtio_transport_connect(struct vsock_sock *vsk)
> >>>  {
> >>>  	struct virtio_vsock_pkt_info info = {
> >>>
> >>
> >> Thanks, Arseniy
> > 
> > Thanks,
> > Bobby