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, 46 insertions, 0 deletions

diff --git a/include/hw/virtio/vhost-backend.h b/include/hw/virtio/vhost-backend.h
index cf7f0b5a69..6e90703cad 100644
--- a/include/hw/virtio/vhost-backend.h
+++ b/include/hw/virtio/vhost-backend.h
@@ -73,6 +73,9 @@ typedef int (*vhost_migration_done_op)(struct vhost_dev *dev,
 typedef bool (*vhost_backend_can_merge_op)(struct vhost_dev *dev,
                                            uint64_t start1, uint64_t size1,
                                            uint64_t start2, uint64_t size2);
+typedef int (*vhost_vsock_set_guest_cid_op)(struct vhost_dev *dev,
+                                            uint64_t guest_cid);
+typedef int (*vhost_vsock_set_running_op)(struct vhost_dev *dev, int start);
 
 typedef struct VhostOps {
     VhostBackendType backend_type;
@@ -102,6 +105,8 @@ typedef struct VhostOps {
     vhost_requires_shm_log_op vhost_requires_shm_log;
     vhost_migration_done_op vhost_migration_done;
     vhost_backend_can_merge_op vhost_backend_can_merge;
+    vhost_vsock_set_guest_cid_op vhost_vsock_set_guest_cid;
+    vhost_vsock_set_running_op vhost_vsock_set_running;
 } VhostOps;
 
 extern const VhostOps user_ops;
diff --git a/include/hw/virtio/vhost-vsock.h b/include/hw/virtio/vhost-vsock.h
new file mode 100644
index 0000000000..7b9205fe3f
--- /dev/null
+++ b/include/hw/virtio/vhost-vsock.h
@@ -0,0 +1,41 @@
+/*
+ * Vhost vsock virtio device
+ *
+ * Copyright 2015 Red Hat, Inc.
+ *
+ * Authors:
+ *  Stefan Hajnoczi <stefanha@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * (at your option) any later version.  See the COPYING file in the
+ * top-level directory.
+ */
+
+#ifndef _QEMU_VHOST_VSOCK_H
+#define _QEMU_VHOST_VSOCK_H
+
+#include "hw/virtio/virtio.h"
+#include "hw/virtio/vhost.h"
+
+#define TYPE_VHOST_VSOCK "vhost-vsock-device"
+#define VHOST_VSOCK(obj) \
+        OBJECT_CHECK(VHostVSock, (obj), TYPE_VHOST_VSOCK)
+
+typedef struct {
+    uint64_t guest_cid;
+    char *vhostfd;
+} VHostVSockConf;
+
+typedef struct {
+    /*< private >*/
+    VirtIODevice parent;
+    VHostVSockConf conf;
+    struct vhost_virtqueue vhost_vqs[2];
+    struct vhost_dev vhost_dev;
+    VirtQueue *event_vq;
+    QEMUTimer *post_load_timer;
+
+    /*< public >*/
+} VHostVSock;
+
+#endif /* _QEMU_VHOST_VSOCK_H */