vhost-vsock: add virtio sockets device

Implement the new virtio sockets device for host<->guest communication
using the Sockets API.  Most of the work is done in a vhost kernel
driver so that virtio-vsock can hook into the AF_VSOCK address family.
The QEMU vhost-vsock device handles configuration and live migration
while the rx/tx happens in the vhost_vsock.ko Linux kernel driver.

The vsock device must be given a CID (host-wide unique address):

  # qemu -device vhost-vsock-pci,id=vhost-vsock-pci0,guest-cid=3 ...

For more information see:
http://qemu-project.org/Features/VirtioVsock

[Endianness fixes and virtio-ccw support by Claudio Imbrenda
<imbrenda@linux.vnet.ibm.com>]

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
[mst: rebase to master]
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

2 files changed, 69 insertions, 0 deletions

diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
index a554a24d06..96789569a7 100644
--- a/hw/s390x/virtio-ccw.c
+++ b/hw/s390x/virtio-ccw.c
@@ -1658,6 +1658,57 @@ static const TypeInfo virtio_ccw_9p_info = {
 };
 #endif
 
+#ifdef CONFIG_VHOST_VSOCK
+
+static Property vhost_vsock_ccw_properties[] = {
+    DEFINE_PROP_CSS_DEV_ID("devno", VirtioCcwDevice, parent_obj.bus_id),
+    DEFINE_PROP_UINT32("max_revision", VirtioCcwDevice, max_rev,
+                       VIRTIO_CCW_MAX_REV),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void vhost_vsock_ccw_realize(VirtioCcwDevice *ccw_dev, Error **errp)
+{
+    VHostVSockCCWState *dev = VHOST_VSOCK_CCW(ccw_dev);
+    DeviceState *vdev = DEVICE(&dev->vdev);
+    Error *err = NULL;
+
+    qdev_set_parent_bus(vdev, BUS(&ccw_dev->bus));
+    object_property_set_bool(OBJECT(vdev), true, "realized", &err);
+    if (err) {
+        error_propagate(errp, err);
+    }
+}
+
+static void vhost_vsock_ccw_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    VirtIOCCWDeviceClass *k = VIRTIO_CCW_DEVICE_CLASS(klass);
+
+    k->realize = vhost_vsock_ccw_realize;
+    k->exit = virtio_ccw_exit;
+    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
+    dc->props = vhost_vsock_ccw_properties;
+    dc->reset = virtio_ccw_reset;
+}
+
+static void vhost_vsock_ccw_instance_init(Object *obj)
+{
+    VHostVSockCCWState *dev = VHOST_VSOCK_CCW(obj);
+
+    virtio_instance_init_common(obj, &dev->vdev, sizeof(dev->vdev),
+                                TYPE_VHOST_VSOCK);
+}
+
+static const TypeInfo vhost_vsock_ccw_info = {
+    .name          = TYPE_VHOST_VSOCK_CCW,
+    .parent        = TYPE_VIRTIO_CCW_DEVICE,
+    .instance_size = sizeof(VHostVSockCCWState),
+    .instance_init = vhost_vsock_ccw_instance_init,
+    .class_init    = vhost_vsock_ccw_class_init,
+};
+#endif
+
 static void virtio_ccw_register(void)
 {
     type_register_static(&virtio_ccw_bus_info);
@@ -1674,6 +1725,9 @@ static void virtio_ccw_register(void)
 #ifdef CONFIG_VIRTFS
     type_register_static(&virtio_ccw_9p_info);
 #endif
+#ifdef CONFIG_VHOST_VSOCK
+    type_register_static(&vhost_vsock_ccw_info);
+#endif
 }
 
 type_init(virtio_ccw_register)
diff --git a/hw/s390x/virtio-ccw.h b/hw/s390x/virtio-ccw.h
index 1c6bc86316..904e357581 100644
--- a/hw/s390x/virtio-ccw.h
+++ b/hw/s390x/virtio-ccw.h
@@ -23,6 +23,9 @@
 #include "hw/virtio/virtio-balloon.h"
 #include "hw/virtio/virtio-rng.h"
 #include "hw/virtio/virtio-bus.h"
+#ifdef CONFIG_VHOST_VSOCK
+#include "hw/virtio/vhost-vsock.h"
+#endif /* CONFIG_VHOST_VSOCK */
 
 #include "hw/s390x/s390_flic.h"
 #include "hw/s390x/css.h"
@@ -197,4 +200,16 @@ typedef struct V9fsCCWState {
 
 #endif /* CONFIG_VIRTFS */
 
+#ifdef CONFIG_VHOST_VSOCK
+#define TYPE_VHOST_VSOCK_CCW "vhost-vsock-ccw"
+#define VHOST_VSOCK_CCW(obj) \
+    OBJECT_CHECK(VHostVSockCCWState, (obj), TYPE_VHOST_VSOCK_CCW)
+
+typedef struct VHostVSockCCWState {
+    VirtioCcwDevice parent_obj;
+    VHostVSock vdev;
+} VHostVSockCCWState;
+
+#endif /* CONFIG_VHOST_VSOCK */
+
 #endif