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

[Stefano Garzarella <sgarzare@redhat.com>]

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@kaspersky.com>
>---
> 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
>