Re: [PATCH net-next v2 3/4] af_vsock: Set VMADDR_FLAG_TO_HOST flag on the receive path

[Stefano Garzarella <sgarzare@redhat.com>]

On Fri, Dec 04, 2020 at 07:02:34PM +0200, Andra Paraschiv wrote:
>The vsock flags can be set during the connect() setup logic, when
>initializing the vsock address data structure variable. Then the vsock
>transport is assigned, also considering this flags field.
>
>The vsock transport is also assigned on the (listen) receive path. The
>flags field needs to be set considering the use case.
>
>Set the value of the vsock flags of the remote address to the one
>targeted for packets forwarding to the host, if the following conditions
>are met:
>
>* The source CID of the packet is higher than VMADDR_CID_HOST.
>* The destination CID of the packet is higher than VMADDR_CID_HOST.
>
>Changelog
>
>v1 -> v2
>
>* Set the vsock flag on the receive path in the vsock transport
>  assignment logic.
>* Use bitwise operator for the vsock flag setup.
>* Use the updated "VMADDR_FLAG_TO_HOST" flag naming.
>
>Signed-off-by: Andra Paraschiv <andraprs@amazon.com>
>---
> net/vmw_vsock/af_vsock.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)

Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>

>
>diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
>index d10916ab45267..83d035eab0b05 100644
>--- a/net/vmw_vsock/af_vsock.c
>+++ b/net/vmw_vsock/af_vsock.c
>@@ -431,6 +431,18 @@ int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk)
> 	unsigned int remote_cid = vsk->remote_addr.svm_cid;
> 	int ret;
>
>+	/* If the packet is coming with the source and destination CIDs higher
>+	 * than VMADDR_CID_HOST, then a vsock channel where all the packets are
>+	 * forwarded to the host should be established. Then the host will
>+	 * need to forward the packets to the guest.
>+	 *
>+	 * The flag is set on the (listen) receive path (psk is not NULL). On
>+	 * the connect path the flag can be set by the user space application.
>+	 */
>+	if (psk && vsk->local_addr.svm_cid > VMADDR_CID_HOST &&
>+	    vsk->remote_addr.svm_cid > VMADDR_CID_HOST)
>+		vsk->remote_addr.svm_flags |= VMADDR_FLAG_TO_HOST;
>+
> 	switch (sk->sk_type) {
> 	case SOCK_DGRAM:
> 		new_transport = transport_dgram;
>-- 
>2.20.1 (Apple Git-117)
>
>
>
>
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>