vhost-vdpa: introduce vhost-vdpa backend

Currently we have 2 types of vhost backends in QEMU: vhost kernel and
vhost-user. The above patch provides a generic device for vDPA purpose,
this vDPA device exposes to user space a non-vendor-specific configuration
interface for setting up a vhost HW accelerator, this patch set introduces
a third vhost backend called vhost-vdpa based on the vDPA interface.

Vhost-vdpa usage:

qemu-system-x86_64 -cpu host -enable-kvm \
    ......
    -netdev type=vhost-vdpa,vhostdev=/dev/vhost-vdpa-id,id=vhost-vdpa0 \
    -device virtio-net-pci,netdev=vhost-vdpa0,page-per-vq=on \

Signed-off-by: Lingshan zhu <lingshan.zhu@intel.com>
Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: Cindy Lu <lulu@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20200701145538.22333-14-lulu@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/include/hw/virtio/vhost-vdpa.h b/include/hw/virtio/vhost-vdpa.h
new file mode 100644
index 0000000000..6455663388
--- /dev/null
+++ b/include/hw/virtio/vhost-vdpa.h
@@ -0,0 +1,26 @@
+/*
+ * vhost-vdpa.h
+ *
+ * Copyright(c) 2017-2018 Intel Corporation.
+ * Copyright(c) 2020 Red Hat, Inc.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#ifndef HW_VIRTIO_VHOST_VDPA_H
+#define HW_VIRTIO_VHOST_VDPA_H
+
+#include "hw/virtio/virtio.h"
+
+typedef struct vhost_vdpa {
+    int device_fd;
+    uint32_t msg_type;
+    MemoryListener listener;
+} VhostVDPA;
+
+extern AddressSpace address_space_memory;
+extern int vhost_vdpa_get_device_id(struct vhost_dev *dev,
+                                   uint32_t *device_id);
+#endif