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

[Stefano Garzarella]

On Sun, Jun 22, 2025 at 09:59:10PM +0800, Xuewei Niu wrote:
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....@antgroup.com>
>---
> 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?

Yep, but let's wait a little bit more.

In that case, please do it in a separate patch (same series is fine) 
that we can easily revert/fix if they will find issues later.

Thanks,
Stefano


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
>