[RFC v1 2/6] virtio/vsock: add support for virtio datagram

[Jiang Wang <jiang.wang@bytedance.com>]

This patch add support for virtio dgram for the driver.
Implemented related functions for tx and rx, enqueue
and dequeue. Send packets synchronously to give sender
indication when the virtqueue is full.
Refactored virtio_transport_send_pkt_work() a little bit but
no functions changes for it.

Support for the host/device side is in another
patch.

Signed-off-by: Jiang Wang <jiang.wang@bytedance.com>
---
 include/net/af_vsock.h                             |   1 +
 .../trace/events/vsock_virtio_transport_common.h   |   5 +-
 include/uapi/linux/virtio_vsock.h                  |   1 +
 net/vmw_vsock/af_vsock.c                           |  12 +
 net/vmw_vsock/virtio_transport.c                   | 325 ++++++++++++++++++---
 net/vmw_vsock/virtio_transport_common.c            | 184 ++++++++++--
 6 files changed, 466 insertions(+), 62 deletions(-)

diff --git a/include/net/af_vsock.h b/include/net/af_vsock.h
index b1c717286993..fcae7bca9609 100644
--- a/include/net/af_vsock.h
+++ b/include/net/af_vsock.h
@@ -200,6 +200,7 @@ void vsock_remove_sock(struct vsock_sock *vsk);
 void vsock_for_each_connected_socket(void (*fn)(struct sock *sk));
 int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk);
 bool vsock_find_cid(unsigned int cid);
+int vsock_bind_stream(struct vsock_sock *vsk, struct sockaddr_vm *addr);
 
 /**** TAP ****/
 
diff --git a/include/trace/events/vsock_virtio_transport_common.h b/include/trace/events/vsock_virtio_transport_common.h
index 6782213778be..b1be25b327a1 100644
--- a/include/trace/events/vsock_virtio_transport_common.h
+++ b/include/trace/events/vsock_virtio_transport_common.h
@@ -9,9 +9,12 @@
 #include <linux/tracepoint.h>
 
 TRACE_DEFINE_ENUM(VIRTIO_VSOCK_TYPE_STREAM);
+TRACE_DEFINE_ENUM(VIRTIO_VSOCK_TYPE_DGRAM);
 
 #define show_type(val) \
-	__print_symbolic(val, { VIRTIO_VSOCK_TYPE_STREAM, "STREAM" })
+	 __print_symbolic(val, \
+					{ VIRTIO_VSOCK_TYPE_STREAM, "STREAM" }, \
+					{ VIRTIO_VSOCK_TYPE_DGRAM, "DGRAM" })
 
 TRACE_DEFINE_ENUM(VIRTIO_VSOCK_OP_INVALID);
 TRACE_DEFINE_ENUM(VIRTIO_VSOCK_OP_REQUEST);
diff --git a/include/uapi/linux/virtio_vsock.h b/include/uapi/linux/virtio_vsock.h
index b56614dff1c9..5503585b26e8 100644
--- a/include/uapi/linux/virtio_vsock.h
+++ b/include/uapi/linux/virtio_vsock.h
@@ -68,6 +68,7 @@ struct virtio_vsock_hdr {
 
 enum virtio_vsock_type {
 	VIRTIO_VSOCK_TYPE_STREAM = 1,
+	VIRTIO_VSOCK_TYPE_DGRAM = 3,
 };
 
 enum virtio_vsock_op {
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 92a72f0e0d94..c1f512291b94 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -659,6 +659,18 @@ static int __vsock_bind_stream(struct vsock_sock *vsk,
 	return 0;
 }
 
+int vsock_bind_stream(struct vsock_sock *vsk,
+				       struct sockaddr_vm *addr)
+{
+	int retval;
+
+	spin_lock_bh(&vsock_table_lock);
+	retval = __vsock_bind_stream(vsk, addr);
+	spin_unlock_bh(&vsock_table_lock);
+	return retval;
+}
+EXPORT_SYMBOL(vsock_bind_stream);
+
 static int __vsock_bind_dgram(struct vsock_sock *vsk,
 			      struct sockaddr_vm *addr)
 {
diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
index 7dcb8db23305..cf47aadb0c34 100644
--- a/net/vmw_vsock/virtio_transport.c
+++ b/net/vmw_vsock/virtio_transport.c
@@ -20,21 +20,29 @@
 #include <net/sock.h>
 #include <linux/mutex.h>
 #include <net/af_vsock.h>
+#include<linux/kobject.h>
+#include<linux/sysfs.h>
+#include <linux/refcount.h>
 
 static struct workqueue_struct *virtio_vsock_workqueue;
 static struct virtio_vsock __rcu *the_virtio_vsock;
+static struct virtio_vsock *the_virtio_vsock_dgram;
 static DEFINE_MUTEX(the_virtio_vsock_mutex); /* protects the_virtio_vsock */
 
 struct virtio_vsock {
 	struct virtio_device *vdev;
 	struct virtqueue **vqs;
 	bool has_dgram;
+	refcount_t active;
 
 	/* Virtqueue processing is deferred to a workqueue */
 	struct work_struct tx_work;
 	struct work_struct rx_work;
 	struct work_struct event_work;
 
+	struct work_struct dgram_tx_work;
+	struct work_struct dgram_rx_work;
+
 	/* The following fields are protected by tx_lock.  vqs[VSOCK_VQ_TX]
 	 * must be accessed with tx_lock held.
 	 */
@@ -55,6 +63,22 @@ struct virtio_vsock {
 	int rx_buf_nr;
 	int rx_buf_max_nr;
 
+	/* The following fields are protected by dgram_tx_lock.  vqs[VSOCK_VQ_DGRAM_TX]
+	 * must be accessed with dgram_tx_lock held.
+	 */
+	struct mutex dgram_tx_lock;
+	bool dgram_tx_run;
+
+	atomic_t dgram_queued_replies;
+
+	/* The following fields are protected by dgram_rx_lock.  vqs[VSOCK_VQ_DGRAM_RX]
+	 * must be accessed with dgram_rx_lock held.
+	 */
+	struct mutex dgram_rx_lock;
+	bool dgram_rx_run;
+	int dgram_rx_buf_nr;
+	int dgram_rx_buf_max_nr;
+
 	/* The following fields are protected by event_lock.
 	 * vqs[VSOCK_VQ_EVENT] must be accessed with event_lock held.
 	 */
@@ -83,21 +107,11 @@ static u32 virtio_transport_get_local_cid(void)
 	return ret;
 }
 
-static void
-virtio_transport_send_pkt_work(struct work_struct *work)
+static void virtio_transport_do_send_pkt(struct virtio_vsock *vsock,
+		struct virtqueue *vq,  spinlock_t *lock, struct list_head *send_pkt_list,
+		bool *restart_rx)
 {
-	struct virtio_vsock *vsock =
-		container_of(work, struct virtio_vsock, send_pkt_work);
-	struct virtqueue *vq;
 	bool added = false;
-	bool restart_rx = false;
-
-	mutex_lock(&vsock->tx_lock);
-
-	if (!vsock->tx_run)
-		goto out;
-
-	vq = vsock->vqs[VSOCK_VQ_TX];
 
 	for (;;) {
 		struct virtio_vsock_pkt *pkt;
@@ -105,16 +119,16 @@ virtio_transport_send_pkt_work(struct work_struct *work)
 		int ret, in_sg = 0, out_sg = 0;
 		bool reply;
 
-		spin_lock_bh(&vsock->send_pkt_list_lock);
-		if (list_empty(&vsock->send_pkt_list)) {
-			spin_unlock_bh(&vsock->send_pkt_list_lock);
+		spin_lock_bh(lock);
+		if (list_empty(send_pkt_list)) {
+			spin_unlock_bh(lock);
 			break;
 		}
 
-		pkt = list_first_entry(&vsock->send_pkt_list,
+		pkt = list_first_entry(send_pkt_list,
 				       struct virtio_vsock_pkt, list);
 		list_del_init(&pkt->list);
-		spin_unlock_bh(&vsock->send_pkt_list_lock);
+		spin_unlock_bh(lock);
 
 		virtio_transport_deliver_tap_pkt(pkt);
 
@@ -132,9 +146,9 @@ virtio_transport_send_pkt_work(struct work_struct *work)
 		 * the vq
 		 */
 		if (ret < 0) {
-			spin_lock_bh(&vsock->send_pkt_list_lock);
-			list_add(&pkt->list, &vsock->send_pkt_list);
-			spin_unlock_bh(&vsock->send_pkt_list_lock);
+			spin_lock_bh(lock);
+			list_add(&pkt->list, send_pkt_list);
+			spin_unlock_bh(lock);
 			break;
 		}
 
@@ -146,7 +160,7 @@ virtio_transport_send_pkt_work(struct work_struct *work)
 
 			/* Do we now have resources to resume rx processing? */
 			if (val + 1 == virtqueue_get_vring_size(rx_vq))
-				restart_rx = true;
+				*restart_rx = true;
 		}
 
 		added = true;
@@ -154,7 +168,55 @@ virtio_transport_send_pkt_work(struct work_struct *work)
 
 	if (added)
 		virtqueue_kick(vq);
+}
 
+static int virtio_transport_do_send_dgram_pkt(struct virtio_vsock *vsock,
+		struct virtqueue *vq, struct virtio_vsock_pkt *pkt)
+{
+	struct scatterlist hdr, buf, *sgs[2];
+	int ret, in_sg = 0, out_sg = 0;
+
+	virtio_transport_deliver_tap_pkt(pkt);
+
+	sg_init_one(&hdr, &pkt->hdr, sizeof(pkt->hdr));
+	sgs[out_sg++] = &hdr;
+	if (pkt->buf) {
+		sg_init_one(&buf, pkt->buf, pkt->len);
+		sgs[out_sg++] = &buf;
+	}
+
+	ret = virtqueue_add_sgs(vq, sgs, out_sg, in_sg, pkt, GFP_KERNEL);
+	/* Usually this means that there is no more space available in
+	 * the vq
+	 */
+	if (ret < 0) {
+		virtio_transport_free_pkt(pkt);
+		return -ENOMEM;
+	}
+
+	virtqueue_kick(vq);
+
+	return pkt->len;
+}
+
+
+static void
+virtio_transport_send_pkt_work(struct work_struct *work)
+{
+	struct virtio_vsock *vsock =
+		container_of(work, struct virtio_vsock, send_pkt_work);
+	struct virtqueue *vq;
+	bool restart_rx = false;
+
+	mutex_lock(&vsock->tx_lock);
+
+	if (!vsock->tx_run)
+		goto out;
+
+	vq = vsock->vqs[VSOCK_VQ_TX];
+
+	virtio_transport_do_send_pkt(vsock, vq, &vsock->send_pkt_list_lock,
+							&vsock->send_pkt_list, &restart_rx);
 out:
 	mutex_unlock(&vsock->tx_lock);
 
@@ -163,11 +225,64 @@ virtio_transport_send_pkt_work(struct work_struct *work)
 }
 
 static int
+virtio_transport_send_dgram_pkt(struct virtio_vsock_pkt *pkt)
+{
+	struct virtio_vsock *vsock;
+	int len = pkt->len;
+	struct virtqueue *vq;
+
+	vsock = the_virtio_vsock_dgram;
+
+	if (!vsock) {
+		virtio_transport_free_pkt(pkt);
+		return -ENODEV;
+	}
+
+	if (!vsock->dgram_tx_run) {
+		virtio_transport_free_pkt(pkt);
+		return -ENODEV;
+	}
+
+	if (!refcount_inc_not_zero(&vsock->active)) {
+		virtio_transport_free_pkt(pkt);
+		return -ENODEV;
+	}
+
+	if (le64_to_cpu(pkt->hdr.dst_cid) == vsock->guest_cid) {
+		virtio_transport_free_pkt(pkt);
+		len = -ENODEV;
+		goto out_ref;
+	}
+
+	/* send the pkt */
+	mutex_lock(&vsock->dgram_tx_lock);
+
+	if (!vsock->dgram_tx_run)
+		goto out_mutex;
+
+	vq = vsock->vqs[VSOCK_VQ_DGRAM_TX];
+
+	len = virtio_transport_do_send_dgram_pkt(vsock, vq, pkt);
+
+out_mutex:
+	mutex_unlock(&vsock->dgram_tx_lock);
+
+out_ref:
+	if (!refcount_dec_not_one(&vsock->active))
+		return -EFAULT;
+
+	return len;
+}
+
+static int
 virtio_transport_send_pkt(struct virtio_vsock_pkt *pkt)
 {
 	struct virtio_vsock *vsock;
 	int len = pkt->len;
 
+	if (pkt->hdr.type == VIRTIO_VSOCK_TYPE_DGRAM)
+		return virtio_transport_send_dgram_pkt(pkt);
+
 	rcu_read_lock();
 	vsock = rcu_dereference(the_virtio_vsock);
 	if (!vsock) {
@@ -243,7 +358,7 @@ virtio_transport_cancel_pkt(struct vsock_sock *vsk)
 	return ret;
 }
 
-static void virtio_vsock_rx_fill(struct virtio_vsock *vsock)
+static void virtio_vsock_rx_fill(struct virtio_vsock *vsock, bool is_dgram)
 {
 	int buf_len = VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE;
 	struct virtio_vsock_pkt *pkt;
@@ -251,7 +366,10 @@ static void virtio_vsock_rx_fill(struct virtio_vsock *vsock)
 	struct virtqueue *vq;
 	int ret;
 
-	vq = vsock->vqs[VSOCK_VQ_RX];
+	if (is_dgram)
+		vq = vsock->vqs[VSOCK_VQ_DGRAM_RX];
+	else
+		vq = vsock->vqs[VSOCK_VQ_RX];
 
 	do {
 		pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
@@ -277,10 +395,19 @@ static void virtio_vsock_rx_fill(struct virtio_vsock *vsock)
 			virtio_transport_free_pkt(pkt);
 			break;
 		}
-		vsock->rx_buf_nr++;
+		if (is_dgram)
+			vsock->dgram_rx_buf_nr++;
+		else
+			vsock->rx_buf_nr++;
 	} while (vq->num_free);
-	if (vsock->rx_buf_nr > vsock->rx_buf_max_nr)
-		vsock->rx_buf_max_nr = vsock->rx_buf_nr;
+	if (is_dgram) {
+		if (vsock->dgram_rx_buf_nr > vsock->dgram_rx_buf_max_nr)
+			vsock->dgram_rx_buf_max_nr = vsock->dgram_rx_buf_nr;
+	} else {
+		if (vsock->rx_buf_nr > vsock->rx_buf_max_nr)
+			vsock->rx_buf_max_nr = vsock->rx_buf_nr;
+	}
+
 	virtqueue_kick(vq);
 }
 
@@ -315,6 +442,34 @@ static void virtio_transport_tx_work(struct work_struct *work)
 		queue_work(virtio_vsock_workqueue, &vsock->send_pkt_work);
 }
 
+static void virtio_transport_dgram_tx_work(struct work_struct *work)
+{
+	struct virtio_vsock *vsock =
+		container_of(work, struct virtio_vsock, dgram_tx_work);
+	struct virtqueue *vq;
+	bool added = false;
+
+	vq = vsock->vqs[VSOCK_VQ_DGRAM_TX];
+	mutex_lock(&vsock->dgram_tx_lock);
+
+	if (!vsock->dgram_tx_run)
+		goto out;
+
+	do {
+		struct virtio_vsock_pkt *pkt;
+		unsigned int len;
+
+		virtqueue_disable_cb(vq);
+		while ((pkt = virtqueue_get_buf(vq, &len)) != NULL) {
+			virtio_transport_free_pkt(pkt);
+			added = true;
+		}
+	} while (!virtqueue_enable_cb(vq));
+
+out:
+	mutex_unlock(&vsock->dgram_tx_lock);
+}
+
 /* Is there space left for replies to rx packets? */
 static bool virtio_transport_more_replies(struct virtio_vsock *vsock)
 {
@@ -449,6 +604,11 @@ static void virtio_vsock_tx_done(struct virtqueue *vq)
 
 static void virtio_vsock_dgram_tx_done(struct virtqueue *vq)
 {
+	struct virtio_vsock *vsock = vq->vdev->priv;
+
+	if (!vsock)
+		return;
+	queue_work(virtio_vsock_workqueue, &vsock->dgram_tx_work);
 }
 
 static void virtio_vsock_rx_done(struct virtqueue *vq)
@@ -462,8 +622,12 @@ static void virtio_vsock_rx_done(struct virtqueue *vq)
 
 static void virtio_vsock_dgram_rx_done(struct virtqueue *vq)
 {
-}
+	struct virtio_vsock *vsock = vq->vdev->priv;
 
+	if (!vsock)
+		return;
+	queue_work(virtio_vsock_workqueue, &vsock->dgram_rx_work);
+}
 static struct virtio_transport virtio_transport = {
 	.transport = {
 		.module                   = THIS_MODULE,
@@ -506,19 +670,9 @@ static struct virtio_transport virtio_transport = {
 	.send_pkt = virtio_transport_send_pkt,
 };
 
-static void virtio_transport_rx_work(struct work_struct *work)
+static void virtio_transport_do_rx_work(struct virtio_vsock *vsock,
+						struct virtqueue *vq, bool is_dgram)
 {
-	struct virtio_vsock *vsock =
-		container_of(work, struct virtio_vsock, rx_work);
-	struct virtqueue *vq;
-
-	vq = vsock->vqs[VSOCK_VQ_RX];
-
-	mutex_lock(&vsock->rx_lock);
-
-	if (!vsock->rx_run)
-		goto out;
-
 	do {
 		virtqueue_disable_cb(vq);
 		for (;;) {
@@ -538,7 +692,10 @@ static void virtio_transport_rx_work(struct work_struct *work)
 				break;
 			}
 
-			vsock->rx_buf_nr--;
+			if (is_dgram)
+				vsock->dgram_rx_buf_nr--;
+			else
+				vsock->rx_buf_nr--;
 
 			/* Drop short/long packets */
 			if (unlikely(len < sizeof(pkt->hdr) ||
@@ -554,11 +711,45 @@ static void virtio_transport_rx_work(struct work_struct *work)
 	} while (!virtqueue_enable_cb(vq));
 
 out:
+	return;
+}
+
+static void virtio_transport_rx_work(struct work_struct *work)
+{
+	struct virtio_vsock *vsock =
+		container_of(work, struct virtio_vsock, rx_work);
+	struct virtqueue *vq;
+
+	vq = vsock->vqs[VSOCK_VQ_RX];
+
+	mutex_lock(&vsock->rx_lock);
+
+	if (vsock->rx_run)
+		virtio_transport_do_rx_work(vsock, vq, false);
+
 	if (vsock->rx_buf_nr < vsock->rx_buf_max_nr / 2)
-		virtio_vsock_rx_fill(vsock);
+		virtio_vsock_rx_fill(vsock, false);
 	mutex_unlock(&vsock->rx_lock);
 }
 
+static void virtio_transport_dgram_rx_work(struct work_struct *work)
+{
+	struct virtio_vsock *vsock =
+		container_of(work, struct virtio_vsock, dgram_rx_work);
+	struct virtqueue *vq;
+
+	vq = vsock->vqs[VSOCK_VQ_DGRAM_RX];
+
+	mutex_lock(&vsock->dgram_rx_lock);
+
+	if (vsock->dgram_rx_run)
+		virtio_transport_do_rx_work(vsock, vq, true);
+
+	if (vsock->dgram_rx_buf_nr < vsock->dgram_rx_buf_max_nr / 2)
+		virtio_vsock_rx_fill(vsock, true);
+	mutex_unlock(&vsock->dgram_rx_lock);
+}
+
 static int virtio_vsock_probe(struct virtio_device *vdev)
 {
 	vq_callback_t *callbacks[] = {
@@ -642,8 +833,14 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
 	vsock->rx_buf_max_nr = 0;
 	atomic_set(&vsock->queued_replies, 0);
 
+	vsock->dgram_rx_buf_nr = 0;
+	vsock->dgram_rx_buf_max_nr = 0;
+	atomic_set(&vsock->dgram_queued_replies, 0);
+
 	mutex_init(&vsock->tx_lock);
 	mutex_init(&vsock->rx_lock);
+	mutex_init(&vsock->dgram_tx_lock);
+	mutex_init(&vsock->dgram_rx_lock);
 	mutex_init(&vsock->event_lock);
 	spin_lock_init(&vsock->send_pkt_list_lock);
 	INIT_LIST_HEAD(&vsock->send_pkt_list);
@@ -651,16 +848,27 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
 	INIT_WORK(&vsock->tx_work, virtio_transport_tx_work);
 	INIT_WORK(&vsock->event_work, virtio_transport_event_work);
 	INIT_WORK(&vsock->send_pkt_work, virtio_transport_send_pkt_work);
+	INIT_WORK(&vsock->dgram_rx_work, virtio_transport_dgram_rx_work);
+	INIT_WORK(&vsock->dgram_tx_work, virtio_transport_dgram_tx_work);
 
 	mutex_lock(&vsock->tx_lock);
 	vsock->tx_run = true;
 	mutex_unlock(&vsock->tx_lock);
 
+	mutex_lock(&vsock->dgram_tx_lock);
+	vsock->dgram_tx_run = true;
+	mutex_unlock(&vsock->dgram_tx_lock);
+
 	mutex_lock(&vsock->rx_lock);
-	virtio_vsock_rx_fill(vsock);
+	virtio_vsock_rx_fill(vsock, false);
 	vsock->rx_run = true;
 	mutex_unlock(&vsock->rx_lock);
 
+	mutex_lock(&vsock->dgram_rx_lock);
+	virtio_vsock_rx_fill(vsock, true);
+	vsock->dgram_rx_run = true;
+	mutex_unlock(&vsock->dgram_rx_lock);
+
 	mutex_lock(&vsock->event_lock);
 	virtio_vsock_event_fill(vsock);
 	vsock->event_run = true;
@@ -669,6 +877,9 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
 	vdev->priv = vsock;
 	rcu_assign_pointer(the_virtio_vsock, vsock);
 
+	the_virtio_vsock_dgram = vsock;
+	refcount_set(&the_virtio_vsock_dgram->active, 1);
+
 	mutex_unlock(&the_virtio_vsock_mutex);
 	return 0;
 
@@ -699,14 +910,28 @@ static void virtio_vsock_remove(struct virtio_device *vdev)
 	vsock->rx_run = false;
 	mutex_unlock(&vsock->rx_lock);
 
+	mutex_lock(&vsock->dgram_rx_lock);
+	vsock->dgram_rx_run = false;
+	mutex_unlock(&vsock->dgram_rx_lock);
+
 	mutex_lock(&vsock->tx_lock);
 	vsock->tx_run = false;
 	mutex_unlock(&vsock->tx_lock);
 
+	mutex_lock(&vsock->dgram_tx_lock);
+	vsock->dgram_tx_run = false;
+	mutex_unlock(&vsock->dgram_tx_lock);
+
 	mutex_lock(&vsock->event_lock);
 	vsock->event_run = false;
 	mutex_unlock(&vsock->event_lock);
 
+	while (!refcount_dec_if_one(&the_virtio_vsock_dgram->active)) {
+		if (signal_pending(current))
+			break;
+		msleep(5);
+	}
+
 	/* Flush all device writes and interrupts, device will not use any
 	 * more buffers.
 	 */
@@ -717,11 +942,21 @@ static void virtio_vsock_remove(struct virtio_device *vdev)
 		virtio_transport_free_pkt(pkt);
 	mutex_unlock(&vsock->rx_lock);
 
+	mutex_lock(&vsock->dgram_rx_lock);
+	while ((pkt = virtqueue_detach_unused_buf(vsock->vqs[VSOCK_VQ_DGRAM_RX])))
+		virtio_transport_free_pkt(pkt);
+	mutex_unlock(&vsock->dgram_rx_lock);
+
 	mutex_lock(&vsock->tx_lock);
 	while ((pkt = virtqueue_detach_unused_buf(vsock->vqs[VSOCK_VQ_TX])))
 		virtio_transport_free_pkt(pkt);
 	mutex_unlock(&vsock->tx_lock);
 
+	mutex_lock(&vsock->dgram_tx_lock);
+	while ((pkt = virtqueue_detach_unused_buf(vsock->vqs[VSOCK_VQ_DGRAM_TX])))
+		virtio_transport_free_pkt(pkt);
+	mutex_unlock(&vsock->dgram_tx_lock);
+
 	spin_lock_bh(&vsock->send_pkt_list_lock);
 	while (!list_empty(&vsock->send_pkt_list)) {
 		pkt = list_first_entry(&vsock->send_pkt_list,
@@ -739,6 +974,8 @@ static void virtio_vsock_remove(struct virtio_device *vdev)
 	 */
 	flush_work(&vsock->rx_work);
 	flush_work(&vsock->tx_work);
+	flush_work(&vsock->dgram_rx_work);
+	flush_work(&vsock->dgram_tx_work);
 	flush_work(&vsock->event_work);
 	flush_work(&vsock->send_pkt_work);
 
@@ -775,7 +1012,7 @@ static int __init virtio_vsock_init(void)
 		return -ENOMEM;
 
 	ret = vsock_core_register(&virtio_transport.transport,
-				  VSOCK_TRANSPORT_F_G2H);
+				  VSOCK_TRANSPORT_F_G2H | VSOCK_TRANSPORT_F_DGRAM);
 	if (ret)
 		goto out_wq;
 
diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
index 902cb6dd710b..9f041515b7f1 100644
--- a/net/vmw_vsock/virtio_transport_common.c
+++ b/net/vmw_vsock/virtio_transport_common.c
@@ -26,6 +26,8 @@
 /* Threshold for detecting small packets to copy */
 #define GOOD_COPY_LEN  128
 
+static s64 virtio_transport_dgram_has_data(struct vsock_sock *vsk);
+
 static const struct virtio_transport *
 virtio_transport_get_ops(struct vsock_sock *vsk)
 {
@@ -196,21 +198,28 @@ static int virtio_transport_send_pkt_info(struct vsock_sock *vsk,
 	vvs = vsk->trans;
 
 	/* we can send less than pkt_len bytes */
-	if (pkt_len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE)
-		pkt_len = VIRTIO_VSOCK_MAX_PKT_BUF_SIZE;
+	if (pkt_len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE) {
+		if (info->type == VIRTIO_VSOCK_TYPE_STREAM)
+			pkt_len = VIRTIO_VSOCK_MAX_PKT_BUF_SIZE;
+		else
+			return 0;
+	}
 
-	/* virtio_transport_get_credit might return less than pkt_len credit */
-	pkt_len = virtio_transport_get_credit(vvs, pkt_len);
+	if (info->type == VIRTIO_VSOCK_TYPE_STREAM) {
+		/* virtio_transport_get_credit might return less than pkt_len credit */
+		pkt_len = virtio_transport_get_credit(vvs, pkt_len);
 
-	/* Do not send zero length OP_RW pkt */
-	if (pkt_len == 0 && info->op == VIRTIO_VSOCK_OP_RW)
-		return pkt_len;
+		/* Do not send zero length OP_RW pkt */
+		if (pkt_len == 0 && info->op == VIRTIO_VSOCK_OP_RW)
+			return pkt_len;
+	}
 
 	pkt = virtio_transport_alloc_pkt(info, pkt_len,
 					 src_cid, src_port,
 					 dst_cid, dst_port);
 	if (!pkt) {
-		virtio_transport_put_credit(vvs, pkt_len);
+		if (info->type == VIRTIO_VSOCK_TYPE_STREAM)
+			virtio_transport_put_credit(vvs, pkt_len);
 		return -ENOMEM;
 	}
 
@@ -397,6 +406,58 @@ virtio_transport_stream_do_dequeue(struct vsock_sock *vsk,
 	return err;
 }
 
+static ssize_t
+virtio_transport_dgram_do_dequeue(struct vsock_sock *vsk,
+						   struct msghdr *msg, size_t len)
+{
+	struct virtio_vsock_sock *vvs = vsk->trans;
+	struct virtio_vsock_pkt *pkt;
+	size_t total = 0;
+	u32 free_space;
+	int err = -EFAULT;
+
+	spin_lock_bh(&vvs->rx_lock);
+	if (total < len && !list_empty(&vvs->rx_queue)) {
+		pkt = list_first_entry(&vvs->rx_queue,
+				       struct virtio_vsock_pkt, list);
+
+		total = len;
+		if (total > pkt->len - pkt->off)
+			total = pkt->len - pkt->off;
+		else if (total < pkt->len - pkt->off)
+			msg->msg_flags |= MSG_TRUNC;
+
+		/* 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);
+
+		err = memcpy_to_msg(msg, pkt->buf + pkt->off, total);
+		if (err)
+			return err;
+
+		spin_lock_bh(&vvs->rx_lock);
+
+		virtio_transport_dec_rx_pkt(vvs, pkt);
+		list_del(&pkt->list);
+		virtio_transport_free_pkt(pkt);
+	}
+
+	free_space = vvs->buf_alloc - (vvs->fwd_cnt - vvs->last_fwd_cnt);
+
+	spin_unlock_bh(&vvs->rx_lock);
+
+	if (total > 0 && msg->msg_name) {
+		/* Provide the address of the sender. */
+		DECLARE_SOCKADDR(struct sockaddr_vm *, vm_addr, msg->msg_name);
+
+		vsock_addr_init(vm_addr, le64_to_cpu(pkt->hdr.src_cid),
+						le32_to_cpu(pkt->hdr.src_port));
+		msg->msg_namelen = sizeof(*vm_addr);
+	}
+	return total;
+}
+
 ssize_t
 virtio_transport_stream_dequeue(struct vsock_sock *vsk,
 				struct msghdr *msg,
@@ -414,7 +475,66 @@ virtio_transport_dgram_dequeue(struct vsock_sock *vsk,
 			       struct msghdr *msg,
 			       size_t len, int flags)
 {
-	return -EOPNOTSUPP;
+	struct sock *sk;
+	size_t err = 0;
+	long timeout;
+
+	DEFINE_WAIT(wait);
+
+	sk = &vsk->sk;
+	err = 0;
+
+	lock_sock(sk);
+
+	if (flags & MSG_OOB || flags & MSG_ERRQUEUE || flags & MSG_PEEK)
+		return -EOPNOTSUPP;
+
+	if (!len)
+		goto out;
+
+	timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
+
+	while (1) {
+		s64 ready;
+
+		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+		ready = virtio_transport_dgram_has_data(vsk);
+
+		if (ready == 0) {
+			if (timeout == 0) {
+				err = -EAGAIN;
+				finish_wait(sk_sleep(sk), &wait);
+				break;
+			}
+
+			release_sock(sk);
+			timeout = schedule_timeout(timeout);
+			lock_sock(sk);
+
+			if (signal_pending(current)) {
+				err = sock_intr_errno(timeout);
+				finish_wait(sk_sleep(sk), &wait);
+				break;
+			} else if (timeout == 0) {
+				err = -EAGAIN;
+				finish_wait(sk_sleep(sk), &wait);
+				break;
+			}
+		} else {
+			finish_wait(sk_sleep(sk), &wait);
+
+			if (ready < 0) {
+				err = -ENOMEM;
+				goto out;
+			}
+
+			err = virtio_transport_dgram_do_dequeue(vsk, msg, len);
+			break;
+		}
+	}
+out:
+	release_sock(sk);
+	return err;
 }
 EXPORT_SYMBOL_GPL(virtio_transport_dgram_dequeue);
 
@@ -431,6 +551,11 @@ s64 virtio_transport_stream_has_data(struct vsock_sock *vsk)
 }
 EXPORT_SYMBOL_GPL(virtio_transport_stream_has_data);
 
+static s64 virtio_transport_dgram_has_data(struct vsock_sock *vsk)
+{
+	return virtio_transport_stream_has_data(vsk);
+}
+
 static s64 virtio_transport_has_space(struct vsock_sock *vsk)
 {
 	struct virtio_vsock_sock *vvs = vsk->trans;
@@ -610,13 +735,15 @@ EXPORT_SYMBOL_GPL(virtio_transport_stream_allow);
 int virtio_transport_dgram_bind(struct vsock_sock *vsk,
 				struct sockaddr_vm *addr)
 {
-	return -EOPNOTSUPP;
+	//use same stream bind for dgram
+	int ret = vsock_bind_stream(vsk, addr);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(virtio_transport_dgram_bind);
 
 bool virtio_transport_dgram_allow(u32 cid, u32 port)
 {
-	return false;
+	return true;
 }
 EXPORT_SYMBOL_GPL(virtio_transport_dgram_allow);
 
@@ -654,7 +781,17 @@ virtio_transport_dgram_enqueue(struct vsock_sock *vsk,
 			       struct msghdr *msg,
 			       size_t dgram_len)
 {
-	return -EOPNOTSUPP;
+	struct virtio_vsock_pkt_info info = {
+		.op = VIRTIO_VSOCK_OP_RW,
+		.type = VIRTIO_VSOCK_TYPE_DGRAM,
+		.msg = msg,
+		.pkt_len = dgram_len,
+		.vsk = vsk,
+		.remote_cid = remote_addr->svm_cid,
+		.remote_port = remote_addr->svm_port,
+	};
+
+	return virtio_transport_send_pkt_info(vsk, &info);
 }
 EXPORT_SYMBOL_GPL(virtio_transport_dgram_enqueue);
 
@@ -729,7 +866,6 @@ static int virtio_transport_reset_no_sock(const struct virtio_transport *t,
 		virtio_transport_free_pkt(reply);
 		return -ENOTCONN;
 	}
-
 	return t->send_pkt(reply);
 }
 
@@ -925,7 +1061,8 @@ virtio_transport_recv_enqueue(struct vsock_sock *vsk,
 		/* 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) {
+		if (pkt->len <= last_pkt->buf_len - last_pkt->len &&
+			pkt->hdr.type == VIRTIO_VSOCK_TYPE_STREAM) {
 			memcpy(last_pkt->buf + last_pkt->len, pkt->buf,
 			       pkt->len);
 			last_pkt->len += pkt->len;
@@ -949,6 +1086,12 @@ virtio_transport_recv_connected(struct sock *sk,
 	struct vsock_sock *vsk = vsock_sk(sk);
 	int err = 0;
 
+	if (le16_to_cpu(pkt->hdr.type == VIRTIO_VSOCK_TYPE_DGRAM)) {
+		virtio_transport_recv_enqueue(vsk, pkt);
+		sk->sk_data_ready(sk);
+		return err;
+	}
+
 	switch (le16_to_cpu(pkt->hdr.op)) {
 	case VIRTIO_VSOCK_OP_RW:
 		virtio_transport_recv_enqueue(vsk, pkt);
@@ -1121,7 +1264,8 @@ 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 (le16_to_cpu(pkt->hdr.type) != VIRTIO_VSOCK_TYPE_STREAM &&
+		le16_to_cpu(pkt->hdr.type) != VIRTIO_VSOCK_TYPE_DGRAM) {
 		(void)virtio_transport_reset_no_sock(t, pkt);
 		goto free_pkt;
 	}
@@ -1150,11 +1294,16 @@ void virtio_transport_recv_pkt(struct virtio_transport *t,
 		goto free_pkt;
 	}
 
-	space_available = virtio_transport_space_update(sk, pkt);
-
 	/* Update CID in case it has changed after a transport reset event */
 	vsk->local_addr.svm_cid = dst.svm_cid;
 
+	if (sk->sk_type == SOCK_DGRAM) {
+		virtio_transport_recv_connected(sk, pkt);
+		goto out;
+	}
+
+	space_available = virtio_transport_space_update(sk, pkt);
+
 	if (space_available)
 		sk->sk_write_space(sk);
 
@@ -1180,6 +1329,7 @@ void virtio_transport_recv_pkt(struct virtio_transport *t,
 		break;
 	}
 
+out:
 	release_sock(sk);
 
 	/* Release refcnt obtained when we fetched this socket out of the
-- 
2.11.0