[PATCH v11 14/18] virtio/vsock: enable SEQPACKET for transport

Arseny Krasnov
2021-06-11T11:14:14Z

To make transport work with SOCK_SEQPACKET add two things:
1) SOCK_SEQPACKET ops for virtio transport and 'seqpacket_allow()'
callback.
2) Handling of SEQPACKET bit: guest tries to negotiate it with vhost,
so feature will be enabled only if bit is negotiated with device.

Signed-off-by: Arseny Krasnov <arseny.krasnov@kaspersky.com>
---
v10 -> v11:
1) 'seqpacket_has_data()' callback set.
2) Commit message updated.

net/vmw_vsock/virtio_transport.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)

diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c
index 2700a63ab095..e73ce652bf3c 100644
--- a/net/vmw_vsock/virtio_transport.c
+++ b/net/vmw_vsock/virtio_transport.c
@@ -62,6 +62,7 @@ struct virtio_vsock {
struct virtio_vsock_event event_list[8];

u32 guest_cid;
+ bool seqpacket_allow;
};

static u32 virtio_transport_get_local_cid(void)
@@ -443,6 +444,8 @@ static void virtio_vsock_rx_done(struct virtqueue *vq)
queue_work(virtio_vsock_workqueue, &vsock->rx_work);
}

+static bool virtio_transport_seqpacket_allow(u32 remote_cid);
+
static struct virtio_transport virtio_transport = {
.transport = {
.module = THIS_MODULE,
@@ -469,6 +472,11 @@ static struct virtio_transport virtio_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 = virtio_transport_seqpacket_allow,
+ .seqpacket_has_data = virtio_transport_seqpacket_has_data,
+
.notify_poll_in = virtio_transport_notify_poll_in,
.notify_poll_out = virtio_transport_notify_poll_out,
.notify_recv_init = virtio_transport_notify_recv_init,
@@ -485,6 +493,19 @@ static struct virtio_transport virtio_transport = {
.send_pkt = virtio_transport_send_pkt,
};

+static bool virtio_transport_seqpacket_allow(u32 remote_cid)
+{
+ struct virtio_vsock *vsock;
+ bool seqpacket_allow;
+
+ rcu_read_lock();
+ vsock = rcu_dereference(the_virtio_vsock);
+ seqpacket_allow = vsock->seqpacket_allow;
+ rcu_read_unlock();
+
+ return seqpacket_allow;
+}
+
static void virtio_transport_rx_work(struct work_struct *work)
{
struct virtio_vsock *vsock =
@@ -608,10 +629,14 @@ static int virtio_vsock_probe(struct virtio_device *vdev)
vsock->event_run = true;
mutex_unlock(&vsock->event_lock);

+ if (virtio_has_feature(vdev, VIRTIO_VSOCK_F_SEQPACKET))
+ vsock->seqpacket_allow = true;
+
vdev->priv = vsock;
rcu_assign_pointer(the_virtio_vsock, vsock);

mutex_unlock(&the_virtio_vsock_mutex);
+
return 0;

out:
@@ -695,6 +720,7 @@ static struct virtio_device_id id_table[] = {
};

static unsigned int features[] = {
+ VIRTIO_VSOCK_F_SEQPACKET
};

static struct virtio_driver virtio_vsock_driver = {
--
2.25.1