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From:   Arseny Krasnov <arseny.krasnov@kaspersky.com>
To:     Stefan Hajnoczi <stefanha@redhat.com>,
        Stefano Garzarella <sgarzare@redhat.com>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Jason Wang <jasowang@redhat.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Jorgen Hansen <jhansen@vmware.com>,
        Colin Ian King <colin.king@canonical.com>,
        Arseniy Krasnov <oxffffaa@gmail.com>,
        Andra Paraschiv <andraprs@amazon.com>,
        Jeff Vander Stoep <jeffv@google.com>
CC:     <kvm@vger.kernel.org>, <virtualization@lists.linux-foundation.org>,
        <netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <stsp2@yandex.ru>, <arseny.krasnov@kaspersky.com>
Subject: [PATCH 1/5] vsock/virtio: support for SOCK_SEQPACKET socket.
Date:   Sun, 3 Jan 2021 22:57:50 +0300
Message-ID: <20210103195752.1954958-1-arseny.krasnov@kaspersky.com>
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References: <20210103195454.1954169-1-arseny.krasnov@kaspersky.com>
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	This extends rx loop for SOCK_SEQPACKET packets and implements
callback which user calls to copy data to its buffer.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
---
 include/linux/virtio_vsock.h            |   7 +
 include/net/af_vsock.h                  |   4 +
 include/uapi/linux/virtio_vsock.h       |   9 +
 net/vmw_vsock/virtio_transport.c        |   3 +
 net/vmw_vsock/virtio_transport_common.c | 323 +++++++++++++++++++++---
 5 files changed, 305 insertions(+), 41 deletions(-)

diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h
index dc636b727179..4902d71b3252 100644
--- a/include/linux/virtio_vsock.h
+++ b/include/linux/virtio_vsock.h
@@ -36,6 +36,10 @@ struct virtio_vsock_sock {
 	u32 rx_bytes;
 	u32 buf_alloc;
 	struct list_head rx_queue;
+
+	/* For SOCK_SEQPACKET */
+	u32 user_read_seq_len;
+	u32 user_read_copied;
 };
 
 struct virtio_vsock_pkt {
@@ -80,6 +84,9 @@ virtio_transport_dgram_dequeue(struct vsock_sock *vsk,
 			       struct msghdr *msg,
 			       size_t len, int flags);
 
+bool virtio_transport_seqpacket_seq_send_len(struct vsock_sock *vsk, size_t len);
+size_t virtio_transport_seqpacket_seq_get_len(struct vsock_sock *vsk);
+
 s64 virtio_transport_stream_has_data(struct vsock_sock *vsk);
 s64 virtio_transport_stream_has_space(struct vsock_sock *vsk);
 
diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
index b1c717286993..792ea7b66574 100644
--- a/include/net/af_vsock.h
+++ b/include/net/af_vsock.h
@@ -135,6 +135,10 @@ struct vsock_transport {
 	bool (*stream_is_active)(struct vsock_sock *);
 	bool (*stream_allow)(u32 cid, u32 port);
 
+	/* SEQ_PACKET. */
+	bool (*seqpacket_seq_send_len)(struct vsock_sock *, size_t len);
+	size_t (*seqpacket_seq_get_len)(struct vsock_sock *);
+
 	/* Notification. */
 	int (*notify_poll_in)(struct vsock_sock *, size_t, bool *);
 	int (*notify_poll_out)(struct vsock_sock *, size_t, bool *);
diff --git a/include/uapi/linux/virtio_vsock.h b/include/uapi/linux/virtio_vsock.h
index 1d57ed3d84d2..058908bc19fc 100644
--- a/include/uapi/linux/virtio_vsock.h
+++ b/include/uapi/linux/virtio_vsock.h
@@ -65,6 +65,7 @@ struct virtio_vsock_hdr {
 
 enum virtio_vsock_type {
 	VIRTIO_VSOCK_TYPE_STREAM = 1,
+	VIRTIO_VSOCK_TYPE_SEQPACKET = 2,
 };
 
 enum virtio_vsock_op {
@@ -83,6 +84,9 @@ enum virtio_vsock_op {
 	VIRTIO_VSOCK_OP_CREDIT_UPDATE = 6,
 	/* Request the peer to send the credit info to us */
 	VIRTIO_VSOCK_OP_CREDIT_REQUEST = 7,
+
+	/* Record begin for SOCK_SEQPACKET */
+	VIRTIO_VSOCK_OP_SEQ_BEGIN = 8,
 };
 
 /* VIRTIO_VSOCK_OP_SHUTDOWN flags values */
@@ -91,4 +95,9 @@ enum virtio_vsock_shutdown {
 	VIRTIO_VSOCK_SHUTDOWN_SEND = 2,
 };
 
+/* VIRTIO_VSOCK_OP_RW flags values for SOCK_SEQPACKET type */
+enum virtio_vsock_rw_seqpacket {
+	VIRTIO_VSOCK_RW_EOR = 1,
+};
+
 #endif /* _UAPI_LINUX_VIRTIO_VSOCK_H */
diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
index 2700a63ab095..2bd3f7cbffcb 100644
--- a/net/vmw_vsock/virtio_transport.c
+++ b/net/vmw_vsock/virtio_transport.c
@@ -469,6 +469,9 @@ static struct virtio_transport virtio_transport = {
 		.stream_is_active         = virtio_transport_stream_is_active,
 		.stream_allow             = virtio_transport_stream_allow,
 
+		.seqpacket_seq_send_len	  = virtio_transport_seqpacket_seq_send_len,
+		.seqpacket_seq_get_len	  = virtio_transport_seqpacket_seq_get_len,
+
 		.notify_poll_in           = virtio_transport_notify_poll_in,
 		.notify_poll_out          = virtio_transport_notify_poll_out,
 		.notify_recv_init         = virtio_transport_notify_recv_init,
diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
index 5956939eebb7..77c42004e422 100644
--- a/net/vmw_vsock/virtio_transport_common.c
+++ b/net/vmw_vsock/virtio_transport_common.c
@@ -139,6 +139,7 @@ static struct sk_buff *virtio_transport_build_skb(void *opaque)
 		break;
 	case VIRTIO_VSOCK_OP_CREDIT_UPDATE:
 	case VIRTIO_VSOCK_OP_CREDIT_REQUEST:
+	case VIRTIO_VSOCK_OP_SEQ_BEGIN:
 		hdr->op = cpu_to_le16(AF_VSOCK_OP_CONTROL);
 		break;
 	default:
@@ -157,6 +158,10 @@ static struct sk_buff *virtio_transport_build_skb(void *opaque)
 
 void virtio_transport_deliver_tap_pkt(struct virtio_vsock_pkt *pkt)
 {
+	/* TODO: implement tap support for SOCK_SEQPACKET. */
+	if (le32_to_cpu(pkt->hdr.type) == VIRTIO_VSOCK_TYPE_SEQPACKET)
+		return;
+
 	if (pkt->tap_delivered)
 		return;
 
@@ -230,10 +235,10 @@ static bool virtio_transport_inc_rx_pkt(struct virtio_vsock_sock *vvs,
 }
 
 static void virtio_transport_dec_rx_pkt(struct virtio_vsock_sock *vvs,
-					struct virtio_vsock_pkt *pkt)
+					u32 len)
 {
-	vvs->rx_bytes -= pkt->len;
-	vvs->fwd_cnt += pkt->len;
+	vvs->rx_bytes -= len;
+	vvs->fwd_cnt += len;
 }
 
 void virtio_transport_inc_tx_pkt(struct virtio_vsock_sock *vvs, struct virtio_vsock_pkt *pkt)
@@ -365,7 +370,7 @@ virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
 		total += bytes;
 		pkt->off += bytes;
 		if (pkt->off == pkt->len) {
-			virtio_transport_dec_rx_pkt(vvs, pkt);
+			virtio_transport_dec_rx_pkt(vvs, pkt->len);
 			list_del(&pkt->list);
 			virtio_transport_free_pkt(pkt);
 		}
@@ -397,15 +402,202 @@ virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
 	return err;
 }
 
+static u16 virtio_transport_get_type(struct sock *sk)
+{
+	if (sk->sk_type == SOCK_STREAM)
+		return VIRTIO_VSOCK_TYPE_STREAM;
+	else
+		return VIRTIO_VSOCK_TYPE_SEQPACKET;
+}
+
+bool virtio_transport_seqpacket_seq_send_len(struct vsock_sock *vsk, size_t len)
+{
+	struct virtio_vsock_pkt_info info = {
+		.type = VIRTIO_VSOCK_TYPE_SEQPACKET,
+		.op = VIRTIO_VSOCK_OP_SEQ_BEGIN,
+		.vsk = vsk,
+		.flags = len
+	};
+
+	return virtio_transport_send_pkt_info(vsk, &info);
+}
+EXPORT_SYMBOL_GPL(virtio_transport_seqpacket_seq_send_len);
+
+static inline void virtio_transport_del_n_free_pkt(struct virtio_vsock_pkt *pkt)
+{
+	list_del(&pkt->list);
+	virtio_transport_free_pkt(pkt);
+}
+
+static size_t virtio_transport_drop_until_seq_begin(struct virtio_vsock_sock *vvs)
+{
+	struct virtio_vsock_pkt *pkt, *n;
+	size_t bytes_dropped = 0;
+
+	list_for_each_entry_safe(pkt, n, &vvs->rx_queue, list) {
+		if (le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_SEQ_BEGIN)
+			break;
+
+		bytes_dropped += le32_to_cpu(pkt->hdr.len);
+		virtio_transport_dec_rx_pkt(vvs, pkt->len);
+		virtio_transport_del_n_free_pkt(pkt);
+	}
+
+	return bytes_dropped;
+}
+
+size_t virtio_transport_seqpacket_seq_get_len(struct vsock_sock *vsk)
+{
+	struct virtio_vsock_sock *vvs = vsk->trans;
+	struct virtio_vsock_pkt *pkt;
+	size_t bytes_dropped;
+
+	spin_lock_bh(&vvs->rx_lock);
+
+	/* Fetch all orphaned 'RW', packets, and
+	 * send credit update.
+	 */
+	bytes_dropped = virtio_transport_drop_until_seq_begin(vvs);
+
+	if (list_empty(&vvs->rx_queue))
+		goto out;
+
+	pkt = list_first_entry(&vvs->rx_queue, struct virtio_vsock_pkt, list);
+
+	vvs->user_read_copied = 0;
+	vvs->user_read_seq_len = le32_to_cpu(pkt->hdr.flags);
+	virtio_transport_del_n_free_pkt(pkt);
+out:
+	spin_unlock_bh(&vvs->rx_lock);
+
+	if (bytes_dropped)
+		virtio_transport_send_credit_update(vsk,
+						    VIRTIO_VSOCK_TYPE_SEQPACKET,
+						    NULL);
+
+	return vvs->user_read_seq_len;
+}
+EXPORT_SYMBOL_GPL(virtio_transport_seqpacket_seq_get_len);
+
+static ssize_t virtio_transport_seqpacket_do_dequeue(struct vsock_sock *vsk,
+						     struct msghdr *msg,
+						     size_t user_buf_len)
+{
+	struct virtio_vsock_sock *vvs = vsk->trans;
+	struct virtio_vsock_pkt *pkt;
+	size_t bytes_handled = 0;
+	int err = 0;
+
+	spin_lock_bh(&vvs->rx_lock);
+
+	if (user_buf_len == 0) {
+		/* User's buffer is full, we processing rest of
+		 * record and drop it. If 'SEQ_BEGIN' is found
+		 * while iterating, user will be woken up,
+		 * because record is already copied, and we
+		 * don't care about absent of some tail RW packets
+		 * of it. Return number of bytes(rest of record),
+		 * but ignore credit update for such absent bytes.
+		 */
+		bytes_handled = virtio_transport_drop_until_seq_begin(vvs);
+		vvs->user_read_copied += bytes_handled;
+
+		if (!list_empty(&vvs->rx_queue) &&
+		    vvs->user_read_copied < vvs->user_read_seq_len) {
+			/* 'SEQ_BEGIN' found, but record isn't complete.
+			 * Set number of copied bytes to fit record size
+			 * and force counters to finish receiving.
+			 */
+			bytes_handled += (vvs->user_read_seq_len - vvs->user_read_copied);
+			vvs->user_read_copied = vvs->user_read_seq_len;
+		}
+	}
+
+	/* Now start copying. */
+	while (vvs->user_read_copied < vvs->user_read_seq_len &&
+	       vvs->rx_bytes &&
+	       user_buf_len &&
+	       !err) {
+		pkt = list_first_entry(&vvs->rx_queue, struct virtio_vsock_pkt, list);
+
+		switch (le16_to_cpu(pkt->hdr.op)) {
+		case VIRTIO_VSOCK_OP_SEQ_BEGIN: {
+			/* Unexpected 'SEQ_BEGIN' during record copy:
+			 * Leave receive loop, 'EAGAIN' will restart it from
+			 * outer receive loop, packet is still in queue and
+			 * counters are cleared. So in next loop enter,
+			 * 'SEQ_BEGIN' will be dequeued first. User's iov
+			 * iterator will be reset in outer loop. Also
+			 * send credit update, because some bytes could be
+			 * copied. User will never see unfinished record.
+			 */
+			err = -EAGAIN;
+			break;
+		}
+		case VIRTIO_VSOCK_OP_RW: {
+			size_t bytes_to_copy;
+			size_t pkt_len;
+
+			pkt_len = (size_t)le32_to_cpu(pkt->hdr.len);
+			bytes_to_copy = min(user_buf_len, pkt_len);
+
+			/* sk_lock is held by caller so no one else can dequeue.
+			 * Unlock rx_lock since memcpy_to_msg() may sleep.
+			 */
+			spin_unlock_bh(&vvs->rx_lock);
+
+			if (memcpy_to_msg(msg, pkt->buf, bytes_to_copy)) {
+				spin_lock_bh(&vvs->rx_lock);
+				err = -EINVAL;
+				break;
+			}
+
+			spin_lock_bh(&vvs->rx_lock);
+			user_buf_len -= bytes_to_copy;
+			bytes_handled += pkt->len;
+			vvs->user_read_copied += bytes_to_copy;
+
+			if (le16_to_cpu(pkt->hdr.flags) & VIRTIO_VSOCK_RW_EOR)
+				msg->msg_flags |= MSG_EOR;
+			break;
+		}
+		default:
+			;
+		}
+
+		/* For unexpected 'SEQ_BEGIN', keep such packet in queue,
+		 * but drop any other type of packet.
+		 */
+		if (le16_to_cpu(pkt->hdr.op) != VIRTIO_VSOCK_OP_SEQ_BEGIN) {
+			virtio_transport_dec_rx_pkt(vvs, pkt->len);
+			virtio_transport_del_n_free_pkt(pkt);
+		}
+	}
+
+	spin_unlock_bh(&vvs->rx_lock);
+
+	virtio_transport_send_credit_update(vsk, VIRTIO_VSOCK_TYPE_SEQPACKET,
+					    NULL);
+
+	return err ?: bytes_handled;
+}
+
 ssize_t
 virtio_transport_stream_dequeue(struct vsock_sock *vsk,
 				struct msghdr *msg,
 				size_t len, int flags)
 {
-	if (flags & MSG_PEEK)
-		return virtio_transport_stream_do_peek(vsk, msg, len);
-	else
+	if (virtio_transport_get_type(sk_vsock(vsk)) == VIRTIO_VSOCK_TYPE_SEQPACKET) {
+		if (flags & MSG_PEEK)
+			return -EOPNOTSUPP;
+
+		return virtio_transport_seqpacket_do_dequeue(vsk, msg, len);
+	} else {
+		if (flags & MSG_PEEK)
+			return virtio_transport_stream_do_peek(vsk, msg, len);
+
 		return virtio_transport_stream_do_dequeue(vsk, msg, len);
+	}
 }
 EXPORT_SYMBOL_GPL(virtio_transport_stream_dequeue);
 
@@ -481,6 +673,8 @@ int virtio_transport_do_socket_init(struct vsock_sock *vsk,
 	spin_lock_init(&vvs->rx_lock);
 	spin_lock_init(&vvs->tx_lock);
 	INIT_LIST_HEAD(&vvs->rx_queue);
+	vvs->user_read_copied = 0;
+	vvs->user_read_seq_len = 0;
 
 	return 0;
 }
@@ -490,13 +684,16 @@ EXPORT_SYMBOL_GPL(virtio_transport_do_socket_init);
 void virtio_transport_notify_buffer_size(struct vsock_sock *vsk, u64 *val)
 {
 	struct virtio_vsock_sock *vvs = vsk->trans;
+	int type;
 
 	if (*val > VIRTIO_VSOCK_MAX_BUF_SIZE)
 		*val = VIRTIO_VSOCK_MAX_BUF_SIZE;
 
 	vvs->buf_alloc = *val;
 
-	virtio_transport_send_credit_update(vsk, VIRTIO_VSOCK_TYPE_STREAM,
+	type = virtio_transport_get_type(sk_vsock(vsk));
+
+	virtio_transport_send_credit_update(vsk, type,
 					    NULL);
 }
 EXPORT_SYMBOL_GPL(virtio_transport_notify_buffer_size);
@@ -624,10 +821,11 @@ int virtio_transport_connect(struct vsock_sock *vsk)
 {
 	struct virtio_vsock_pkt_info info = {
 		.op = VIRTIO_VSOCK_OP_REQUEST,
-		.type = VIRTIO_VSOCK_TYPE_STREAM,
 		.vsk = vsk,
 	};
 
+	info.type = virtio_transport_get_type(sk_vsock(vsk));
+
 	return virtio_transport_send_pkt_info(vsk, &info);
 }
 EXPORT_SYMBOL_GPL(virtio_transport_connect);
@@ -636,7 +834,6 @@ int virtio_transport_shutdown(struct vsock_sock *vsk, int mode)
 {
 	struct virtio_vsock_pkt_info info = {
 		.op = VIRTIO_VSOCK_OP_SHUTDOWN,
-		.type = VIRTIO_VSOCK_TYPE_STREAM,
 		.flags = (mode & RCV_SHUTDOWN ?
 			  VIRTIO_VSOCK_SHUTDOWN_RCV : 0) |
 			 (mode & SEND_SHUTDOWN ?
@@ -644,6 +841,8 @@ int virtio_transport_shutdown(struct vsock_sock *vsk, int mode)
 		.vsk = vsk,
 	};
 
+	info.type = virtio_transport_get_type(sk_vsock(vsk));
+
 	return virtio_transport_send_pkt_info(vsk, &info);
 }
 EXPORT_SYMBOL_GPL(virtio_transport_shutdown);
@@ -665,12 +864,18 @@ virtio_transport_stream_enqueue(struct vsock_sock *vsk,
 {
 	struct virtio_vsock_pkt_info info = {
 		.op = VIRTIO_VSOCK_OP_RW,
-		.type = VIRTIO_VSOCK_TYPE_STREAM,
 		.msg = msg,
 		.pkt_len = len,
 		.vsk = vsk,
+		.flags = 0,
 	};
 
+	info.type = virtio_transport_get_type(sk_vsock(vsk));
+
+	if (info.type == VIRTIO_VSOCK_TYPE_SEQPACKET &&
+	    msg->msg_flags & MSG_EOR)
+		info.flags |= VIRTIO_VSOCK_RW_EOR;
+
 	return virtio_transport_send_pkt_info(vsk, &info);
 }
 EXPORT_SYMBOL_GPL(virtio_transport_stream_enqueue);
@@ -688,7 +893,6 @@ static int virtio_transport_reset(struct vsock_sock *vsk,
 {
 	struct virtio_vsock_pkt_info info = {
 		.op = VIRTIO_VSOCK_OP_RST,
-		.type = VIRTIO_VSOCK_TYPE_STREAM,
 		.reply = !!pkt,
 		.vsk = vsk,
 	};
@@ -697,6 +901,8 @@ static int virtio_transport_reset(struct vsock_sock *vsk,
 	if (pkt && le16_to_cpu(pkt->hdr.op) == VIRTIO_VSOCK_OP_RST)
 		return 0;
 
+	info.type = virtio_transport_get_type(sk_vsock(vsk));
+
 	return virtio_transport_send_pkt_info(vsk, &info);
 }
 
@@ -884,44 +1090,59 @@ virtio_transport_recv_connecting(struct sock *sk,
 	return err;
 }
 
-static void
+static bool
 virtio_transport_recv_enqueue(struct vsock_sock *vsk,
 			      struct virtio_vsock_pkt *pkt)
 {
 	struct virtio_vsock_sock *vvs = vsk->trans;
-	bool can_enqueue, free_pkt = false;
+	bool data_ready = false;
+	bool free_pkt = false;
 
-	pkt->len = le32_to_cpu(pkt->hdr.len);
 	pkt->off = 0;
+	pkt->len = le32_to_cpu(pkt->hdr.len);
 
 	spin_lock_bh(&vvs->rx_lock);
 
-	can_enqueue = virtio_transport_inc_rx_pkt(vvs, pkt);
-	if (!can_enqueue) {
-		free_pkt = true;
-		goto out;
-	}
+	switch (le32_to_cpu(pkt->hdr.type)) {
+	case VIRTIO_VSOCK_TYPE_STREAM: {
+		if (!virtio_transport_inc_rx_pkt(vvs, pkt)) {
+			free_pkt = true;
+			goto out;
+		}
 
-	/* Try to copy small packets into the buffer of last packet queued,
-	 * to avoid wasting memory queueing the entire buffer with a small
-	 * payload.
-	 */
-	if (pkt->len <= GOOD_COPY_LEN && !list_empty(&vvs->rx_queue)) {
-		struct virtio_vsock_pkt *last_pkt;
+		/* Try to copy small packets into the buffer of last packet queued,
+		 * to avoid wasting memory queueing the entire buffer with a small
+		 * payload.
+		 */
+		if (pkt->len <= GOOD_COPY_LEN && !list_empty(&vvs->rx_queue)) {
+			struct virtio_vsock_pkt *last_pkt;
 
-		last_pkt = list_last_entry(&vvs->rx_queue,
-					   struct virtio_vsock_pkt, list);
+			last_pkt = list_last_entry(&vvs->rx_queue,
+						   struct virtio_vsock_pkt, list);
 
-		/* If there is space in the last packet queued, we copy the
-		 * new packet in its buffer.
-		 */
-		if (pkt->len <= last_pkt->buf_len - last_pkt->len) {
-			memcpy(last_pkt->buf + last_pkt->len, pkt->buf,
-			       pkt->len);
-			last_pkt->len += pkt->len;
-			free_pkt = true;
-			goto out;
+			/* If there is space in the last packet queued, we copy the
+			 * new packet in its buffer.
+			 */
+			if (pkt->len <= last_pkt->buf_len - last_pkt->len) {
+				memcpy(last_pkt->buf + last_pkt->len, pkt->buf,
+				       pkt->len);
+				last_pkt->len += pkt->len;
+				free_pkt = true;
+				goto out;
+			}
 		}
+
+		data_ready = true;
+		break;
+	}
+
+	case VIRTIO_VSOCK_TYPE_SEQPACKET: {
+		data_ready = true;
+		vvs->rx_bytes += pkt->len;
+		break;
+	}
+	default:
+		goto out;
 	}
 
 	list_add_tail(&pkt->list, &vvs->rx_queue);
@@ -930,6 +1151,8 @@ virtio_transport_recv_enqueue(struct vsock_sock *vsk,
 	spin_unlock_bh(&vvs->rx_lock);
 	if (free_pkt)
 		virtio_transport_free_pkt(pkt);
+
+	return data_ready;
 }
 
 static int
@@ -940,9 +1163,17 @@ virtio_transport_recv_connected(struct sock *sk,
 	int err = 0;
 
 	switch (le16_to_cpu(pkt->hdr.op)) {
+	case VIRTIO_VSOCK_OP_SEQ_BEGIN: {
+		struct virtio_vsock_sock *vvs = vsk->trans;
+
+		spin_lock_bh(&vvs->rx_lock);
+		list_add_tail(&pkt->list, &vvs->rx_queue);
+		spin_unlock_bh(&vvs->rx_lock);
+		return err;
+	}
 	case VIRTIO_VSOCK_OP_RW:
-		virtio_transport_recv_enqueue(vsk, pkt);
-		sk->sk_data_ready(sk);
+		if (virtio_transport_recv_enqueue(vsk, pkt))
+			sk->sk_data_ready(sk);
 		return err;
 	case VIRTIO_VSOCK_OP_CREDIT_UPDATE:
 		sk->sk_write_space(sk);
@@ -990,13 +1221,14 @@ virtio_transport_send_response(struct vsock_sock *vsk,
 {
 	struct virtio_vsock_pkt_info info = {
 		.op = VIRTIO_VSOCK_OP_RESPONSE,
-		.type = VIRTIO_VSOCK_TYPE_STREAM,
 		.remote_cid = le64_to_cpu(pkt->hdr.src_cid),
 		.remote_port = le32_to_cpu(pkt->hdr.src_port),
 		.reply = true,
 		.vsk = vsk,
 	};
 
+	info.type = virtio_transport_get_type(sk_vsock(vsk));
+
 	return virtio_transport_send_pkt_info(vsk, &info);
 }
 
@@ -1086,6 +1318,12 @@ virtio_transport_recv_listen(struct sock *sk, struct virtio_vsock_pkt *pkt,
 	return 0;
 }
 
+static bool virtio_transport_valid_type(u16 type)
+{
+	return (type == VIRTIO_VSOCK_TYPE_STREAM) ||
+	       (type == VIRTIO_VSOCK_TYPE_SEQPACKET);
+}
+
 /* We are under the virtio-vsock's vsock->rx_lock or vhost-vsock's vq->mutex
  * lock.
  */
@@ -1111,7 +1349,7 @@ void virtio_transport_recv_pkt(struct virtio_transport *t,
 					le32_to_cpu(pkt->hdr.buf_alloc),
 					le32_to_cpu(pkt->hdr.fwd_cnt));
 
-	if (le16_to_cpu(pkt->hdr.type) != VIRTIO_VSOCK_TYPE_STREAM) {
+	if (!virtio_transport_valid_type(le16_to_cpu(pkt->hdr.type))) {
 		(void)virtio_transport_reset_no_sock(t, pkt);
 		goto free_pkt;
 	}
@@ -1128,6 +1366,9 @@ void virtio_transport_recv_pkt(struct virtio_transport *t,
 		}
 	}
 
+	if (virtio_transport_get_type(sk) != le16_to_cpu(pkt->hdr.type))
+		goto free_pkt;
+
 	vsk = vsock_sk(sk);
 
 	space_available = virtio_transport_space_update(sk, pkt);
-- 
2.25.1