As vhost places data in buffers of guest's rx queue, keep SEQ_EOR
bit set only when last piece of data is copied. Otherwise we get
sequence packets for one socket in guest's rx queue with SEQ_EOR bit
set. Also remove ignore of non-stream type of packets, handle SEQPACKET
feature bit.

Signed-off-by: Arseny Krasnov <redacted>
---
v9 -> v10:
1) Move 'restore_flag' handling to 'payload_len' calculation
   block.

drivers/vhost/vsock.c | 44 +++++++++++++++++++++++++++++++++++++++----
1 file changed, 40 insertions(+), 4 deletions(-)

diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
index 5e78fb719602..63d15beaad05 100644
--- a/drivers/vhost/vsock.c
+++ b/drivers/vhost/vsock.c

@@ -31,7 +31,8 @@

enum {
	VHOST_VSOCK_FEATURES = VHOST_FEATURES |
-			       (1ULL << VIRTIO_F_ACCESS_PLATFORM)
+			       (1ULL << VIRTIO_F_ACCESS_PLATFORM) |
+			       (1ULL << VIRTIO_VSOCK_F_SEQPACKET)
};

enum {

@@ -56,6 +57,7 @@ struct vhost_vsock {

	atomic_t queued_replies;

	u32 guest_cid;
+	bool seqpacket_allow;
};

static u32 vhost_transport_get_local_cid(void)

@@ -112,6 +114,7 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock,

		size_t nbytes;
		size_t iov_len, payload_len;
		int head;
+		bool restore_flag = false;

		spin_lock_bh(&vsock->send_pkt_list_lock);
		if (list_empty(&vsock->send_pkt_list)) {

@@ -168,9 +171,15 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock,

		/* If the packet is greater than the space available in the
		 * buffer, we split it using multiple buffers.
		 */
-		if (payload_len > iov_len - sizeof(pkt->hdr))
+		if (payload_len > iov_len - sizeof(pkt->hdr)) {
			payload_len = iov_len - sizeof(pkt->hdr);

+			if (le32_to_cpu(pkt->hdr.flags) & 
VIRTIO_VSOCK_SEQ_EOR) {
+				pkt->hdr.flags &= ~cpu_to_le32(VIRTIO_VSOCK_SEQ_EOR);
+				restore_flag = true;
+			}
+		}
+
		/* Set the correct length in the header */
		pkt->hdr.len = cpu_to_le32(payload_len);

@@ -181,6 +190,9 @@ vhost_transport_do_send_pkt(struct vhost_vsock 

*vsock,
			break;
		}

+		if (restore_flag)
+			pkt->hdr.flags |= cpu_to_le32(VIRTIO_VSOCK_SEQ_EOR);
+

		nbytes = copy_to_iter(pkt->buf + pkt->off, payload_len,
				      &iov_iter);
		if (nbytes != payload_len) {

@@ -354,8 +366,7 @@ vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq,

		return NULL;
	}

-	if (le16_to_cpu(pkt->hdr.type) == VIRTIO_VSOCK_TYPE_STREAM)
-		pkt->len = le32_to_cpu(pkt->hdr.len);
+	pkt->len = le32_to_cpu(pkt->hdr.len);

	/* No payload */
	if (!pkt->len)

@@ -398,6 +409,8 @@ static bool vhost_vsock_more_replies(struct 

vhost_vsock *vsock)
	return val < vq->num;
}

+static bool vhost_transport_seqpacket_allow(u32 remote_cid);
+
static struct virtio_transport vhost_transport = {
	.transport = {
		.module                   = THIS_MODULE,

@@ -424,6 +437,10 @@ static struct virtio_transport vhost_transport = {

		.stream_is_active         = virtio_transport_stream_is_active,
		.stream_allow             = virtio_transport_stream_allow,

+		.seqpacket_dequeue        = virtio_transport_seqpacket_dequeue,
+		.seqpacket_enqueue        = virtio_transport_seqpacket_enqueue,
+		.seqpacket_allow          = vhost_transport_seqpacket_allow,
+
		.notify_poll_in           = virtio_transport_notify_poll_in,
		.notify_poll_out          = virtio_transport_notify_poll_out,
		.notify_recv_init         = virtio_transport_notify_recv_init,

@@ -441,6 +458,22 @@ static struct virtio_transport vhost_transport = {

	.send_pkt = vhost_transport_send_pkt,
};

+static bool vhost_transport_seqpacket_allow(u32 remote_cid)
+{
+	struct vhost_vsock *vsock;
+	bool seqpacket_allow = false;
+
+	rcu_read_lock();
+	vsock = vhost_vsock_get(remote_cid);
+
+	if (vsock)
+		seqpacket_allow = vsock->seqpacket_allow;
+
+	rcu_read_unlock();
+
+	return seqpacket_allow;
+}
+
static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
{
	struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,

@@ -785,6 +818,9 @@ static int vhost_vsock_set_features(struct vhost_vsock *vsock, u64 features)

			goto err;
	}

+	if (features & (1ULL << VIRTIO_VSOCK_F_SEQPACKET))
+		vsock->seqpacket_allow = true;
+
	for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) {
		vq = &vsock->vqs[i];
		mutex_lock(&vq->mutex);
-- 
2.25.1