Re: [RFC PATCH v4 06/17] af_vsock: implement send logic for SEQPACKET

[Stefano Garzarella]

On Sun, Feb 07, 2021 at 06:15:57PM +0300, Arseny Krasnov wrote:
> This adds some logic to current stream enqueue function for SEQPACKET
> support:
> 1) Send record's begin/end marker.
> 2) Return value from enqueue function is whole record length or error
>   for SOCK_SEQPACKET.
>
> Signed-off-by: Arseny Krasnov <arseny.krasnov@xxxxxxxxxxxxx>
> ---
> include/net/af_vsock.h   |  2 ++
> net/vmw_vsock/af_vsock.c | 22 ++++++++++++++++++++--
> 2 files changed, 22 insertions(+), 2 deletions(-)
>
> diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
> index 19f6f22821ec..198d58c4c7ee 100644
> --- a/include/net/af_vsock.h
> +++ b/include/net/af_vsock.h
> @@ -136,6 +136,8 @@ struct vsock_transport {
> 	bool (*stream_allow)(u32 cid, u32 port);
>
> 	/* SEQ_PACKET. */
> +	int (*seqpacket_seq_send_len)(struct vsock_sock *, size_t len, int flags);
> +	int (*seqpacket_seq_send_eor)(struct vsock_sock *, int flags);

As before, we could add the identifier of the parameters.

Other than that, the patch LGTM.

Stefano

> 	size_t (*seqpacket_seq_get_len)(struct vsock_sock *);
> 	int (*seqpacket_dequeue)(struct vsock_sock *, struct msghdr *,
> 				     int flags, bool *msg_ready);
> diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
> index ea99261e88ac..a033d3340ac4 100644
> --- a/net/vmw_vsock/af_vsock.c
> +++ b/net/vmw_vsock/af_vsock.c
> @@ -1806,6 +1806,12 @@ static int vsock_connectible_sendmsg(struct socket *sock, struct msghdr *msg,
> 	if (err < 0)
> 		goto out;
>
> +	if (sk->sk_type == SOCK_SEQPACKET) {
> +		err = transport->seqpacket_seq_send_len(vsk, len, msg->msg_flags);
> +		if (err < 0)
> +			goto out;
> +	}
> +
> 	while (total_written < len) {
> 		ssize_t written;
>
> @@ -1852,9 +1858,21 @@ static int vsock_connectible_sendmsg(struct socket *sock, struct msghdr *msg,
>
> 	}
>
> +	if (sk->sk_type == SOCK_SEQPACKET) {
> +		err = transport->seqpacket_seq_send_eor(vsk, msg->msg_flags);
> +		if (err < 0)
> +			goto out;
> +	}
> +
> out_err:
> -	if (total_written > 0)
> -		err = total_written;
> +	if (total_written > 0) {
> +		/* Return number of written bytes only if:
> +		 * 1) SOCK_STREAM socket.
> +		 * 2) SOCK_SEQPACKET socket when whole buffer is sent.
> +		 */
> +		if (sk->sk_type == SOCK_STREAM || total_written == len)
> +			err = total_written;
> +	}
> out:
> 	release_sock(sk);
> 	return err;
> --
> 2.25.1