Re: [PATCH net-next v3 1/3] vsock: Add support for SIOCINQ ioctl

[Xuewei Niu]

> ACCin hyper-v maintainers and list since I have a question about hyperv 
> transport.
> 
> On Tue, Jun 17, 2025 at 12:53:44PM +0800, Xuewei Niu wrote:
> >Add support for SIOCINQ ioctl, indicating the length of bytes unread in the
> >socket. The value is obtained from `vsock_stream_has_data()`.
> >
> >Signed-off-by: Xuewei Niu <niuxuewei.nxw@xxxxxxxxxxxx>
> >---
> > net/vmw_vsock/af_vsock.c | 22 ++++++++++++++++++++++
> > 1 file changed, 22 insertions(+)
> >
> >diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
> >index 2e7a3034e965..bae6b89bb5fb 100644
> >--- a/net/vmw_vsock/af_vsock.c
> >+++ b/net/vmw_vsock/af_vsock.c
> >@@ -1389,6 +1389,28 @@ static int vsock_do_ioctl(struct socket *sock, unsigned int cmd,
> > 	vsk = vsock_sk(sk);
> >
> > 	switch (cmd) {
> >+	case SIOCINQ: {
> >+		ssize_t n_bytes;
> >+
> >+		if (!vsk->transport) {
> >+			ret = -EOPNOTSUPP;
> >+			break;
> >+		}
> >+
> >+		if (sock_type_connectible(sk->sk_type) &&
> >+		    sk->sk_state == TCP_LISTEN) {
> >+			ret = -EINVAL;
> >+			break;
> >+		}
> >+
> >+		n_bytes = vsock_stream_has_data(vsk);
> 
> Now looks better to me, I just checked transports: vmci and virtio/vhost 
> returns what we want, but for hyperv we have:
> 
> 	static s64 hvs_stream_has_data(struct vsock_sock *vsk)
> 	{
> 		struct hvsock *hvs = vsk->trans;
> 		s64 ret;
> 
> 		if (hvs->recv_data_len > 0)
> 			return 1;
> 
> @Hyper-v maintainers: do you know why we don't return `recv_data_len`?
> Do you think we can do that to support this new feature?

Hi Hyper-v maintainers, could you please take a look at this?

Hi Stefano, if no response, can I fix this issue in the next version?

Thanks,
Xuewei
 
> Thanks,
> Stefano
> 
> >+		if (n_bytes < 0) {
> >+			ret = n_bytes;
> >+			break;
> >+		}
> >+		ret = put_user(n_bytes, arg);
> >+		break;
> >+	}
> > 	case SIOCOUTQ: {
> > 		ssize_t n_bytes;
> >
> >-- 
> >2.34.1
> >