[RFC PATCH v8 13/19] virtio/vsock: rest of SOCK_SEQPACKET support

[Arseny Krasnov]

This adds rest of logic for SEQPACKET:
1) Send SHUTDOWN on socket close for SEQPACKET type.
2) Set SEQPACKET packet type during send.
3) 'seqpacket_allow' flag to virtio transport.
4) Set 'VIRTIO_VSOCK_SEQ_EOR' bit in flags for last
   packet of message.

Signed-off-by: Arseny Krasnov <arseny.kras...@kaspersky.com>
---
v7 -> v8:
 - MSG_EOR handling is removed, i didn't found exact description about
   how it works in POSIX.
 - SEQ_BEGIN, SEQ_END, etc. now removed.

 include/linux/virtio_vsock.h            |  6 ++++++
 net/vmw_vsock/virtio_transport_common.c | 16 ++++++++++++++--
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h
index 02acf6e9ae04..f00a01bfdd7e 100644
--- a/include/linux/virtio_vsock.h
+++ b/include/linux/virtio_vsock.h
@@ -68,6 +68,8 @@ struct virtio_transport {
 
        /* Takes ownership of the packet */
        int (*send_pkt)(struct virtio_vsock_pkt *pkt);
+
+       bool seqpacket_allow;
 };
 
 ssize_t
@@ -80,6 +82,10 @@ virtio_transport_dgram_dequeue(struct vsock_sock *vsk,
                               struct msghdr *msg,
                               size_t len, int flags);
 
+int
+virtio_transport_seqpacket_enqueue(struct vsock_sock *vsk,
+                                  struct msghdr *msg,
+                                  size_t len);
 ssize_t
 virtio_transport_seqpacket_dequeue(struct vsock_sock *vsk,
                                   struct msghdr *msg,
diff --git a/net/vmw_vsock/virtio_transport_common.c 
b/net/vmw_vsock/virtio_transport_common.c
index 572869fef832..4c5b63601308 100644
--- a/net/vmw_vsock/virtio_transport_common.c
+++ b/net/vmw_vsock/virtio_transport_common.c
@@ -74,6 +74,9 @@ virtio_transport_alloc_pkt(struct virtio_vsock_pkt_info *info,
                err = memcpy_from_msg(pkt->buf, info->msg, len);
                if (err)
                        goto out;
+
+               if (info->msg->msg_iter.count == 0)
+                       pkt->hdr.flags |= VIRTIO_VSOCK_SEQ_EOR;
        }
 
        trace_virtio_transport_alloc_pkt(src_cid, src_port,
@@ -187,7 +190,7 @@ static int virtio_transport_send_pkt_info(struct vsock_sock 
*vsk,
        struct virtio_vsock_pkt *pkt;
        u32 pkt_len = info->pkt_len;
 
-       info->type = VIRTIO_VSOCK_TYPE_STREAM;
+       info->type = virtio_transport_get_type(sk_vsock(vsk));
 
        t_ops = virtio_transport_get_ops(vsk);
        if (unlikely(!t_ops))
@@ -486,6 +489,15 @@ virtio_transport_seqpacket_dequeue(struct vsock_sock *vsk,
 }
 EXPORT_SYMBOL_GPL(virtio_transport_seqpacket_dequeue);
 
+int
+virtio_transport_seqpacket_enqueue(struct vsock_sock *vsk,
+                                  struct msghdr *msg,
+                                  size_t len)
+{
+       return virtio_transport_stream_enqueue(vsk, msg, len);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_seqpacket_enqueue);
+
 int
 virtio_transport_dgram_dequeue(struct vsock_sock *vsk,
                               struct msghdr *msg,
@@ -905,7 +917,7 @@ void virtio_transport_release(struct vsock_sock *vsk)
        struct sock *sk = &vsk->sk;
        bool remove_sock = true;
 
-       if (sk->sk_type == SOCK_STREAM)
+       if (sk->sk_type == SOCK_STREAM || sk->sk_type == SOCK_SEQPACKET)
                remove_sock = virtio_transport_close(vsk);
 
        list_for_each_entry_safe(pkt, tmp, &vvs->rx_queue, list) {
-- 
2.25.1