hw/display: add vhost-user-vga & gpu-pci

Add new virtio-gpu devices with a "vhost-user" property. The
associated vhost-user backend is used to handle the virtio rings and
provide rendering results thanks to the vhost-user-gpu protocol.

Example usage:
-object vhost-user-backend,id=vug,cmd="./vhost-user-gpu"
-device vhost-user-vga,vhost-user=vug

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20190524130946.31736-10-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

hw/display/Kconfig

@@ -111,6 +111,16 @@ config VIRTIO_VGA
     depends on VIRTIO_PCI
     select VGA
 
+config VHOST_USER_GPU
+    bool
+    default y
+    depends on VIRTIO_GPU && VHOST_USER
+
+config VHOST_USER_VGA
+    bool
+    default y
+    depends on VIRTIO_VGA && VHOST_USER_GPU
+
 config DPCD
     bool
     select AUX

hw/display/Makefile.objs

@@ -44,8 +44,11 @@ obj-$(CONFIG_VGA) += vga.o
 common-obj-$(CONFIG_QXL) += qxl.o qxl-logger.o qxl-render.o
 
 obj-$(CONFIG_VIRTIO_GPU) += virtio-gpu-base.o virtio-gpu.o virtio-gpu-3d.o
+obj-$(CONFIG_VHOST_USER_GPU) += vhost-user-gpu.o
 obj-$(call land,$(CONFIG_VIRTIO_GPU),$(CONFIG_VIRTIO_PCI)) += virtio-gpu-pci.o
+obj-$(call land,$(CONFIG_VHOST_USER_GPU),$(CONFIG_VIRTIO_PCI)) += vhost-user-gpu-pci.o
 obj-$(CONFIG_VIRTIO_VGA) += virtio-vga.o
+obj-$(CONFIG_VHOST_USER_VGA) += vhost-user-vga.o
 virtio-gpu.o-cflags := $(VIRGL_CFLAGS)
 virtio-gpu.o-libs += $(VIRGL_LIBS)
 virtio-gpu-3d.o-cflags := $(VIRGL_CFLAGS)

hw/display/vhost-user-gpu-pci.c

@@ -0,0 +1,51 @@
+/*
+ * vhost-user GPU PCI device
+ *
+ * Copyright Red Hat, Inc. 2018
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "hw/virtio/virtio-gpu-pci.h"
+
+#define TYPE_VHOST_USER_GPU_PCI "vhost-user-gpu-pci"
+#define VHOST_USER_GPU_PCI(obj)                                     \
+    OBJECT_CHECK(VhostUserGPUPCI, (obj), TYPE_VHOST_USER_GPU_PCI)
+
+typedef struct VhostUserGPUPCI {
+    VirtIOGPUPCIBase parent_obj;
+
+    VhostUserGPU vdev;
+} VhostUserGPUPCI;
+
+static void vhost_user_gpu_pci_initfn(Object *obj)
+{
+    VhostUserGPUPCI *dev = VHOST_USER_GPU_PCI(obj);
+
+    virtio_instance_init_common(obj, &dev->vdev, sizeof(dev->vdev),
+                                TYPE_VHOST_USER_GPU);
+
+    VIRTIO_GPU_PCI_BASE(obj)->vgpu = VIRTIO_GPU_BASE(&dev->vdev);
+
+    object_property_add_alias(obj, "chardev",
+                              OBJECT(&dev->vdev), "chardev",
+                              &error_abort);
+}
+
+static const VirtioPCIDeviceTypeInfo vhost_user_gpu_pci_info = {
+    .generic_name = TYPE_VHOST_USER_GPU_PCI,
+    .parent = TYPE_VIRTIO_GPU_PCI_BASE,
+    .instance_size = sizeof(VhostUserGPUPCI),
+    .instance_init = vhost_user_gpu_pci_initfn,
+};
+
+static void vhost_user_gpu_pci_register_types(void)
+{
+    virtio_pci_types_register(&vhost_user_gpu_pci_info);
+}
+
+type_init(vhost_user_gpu_pci_register_types)

hw/display/vhost-user-vga.c

@@ -0,0 +1,52 @@
+/*
+ * vhost-user VGA device
+ *
+ * Copyright Red Hat, Inc. 2018
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "virtio-vga.h"
+
+#define TYPE_VHOST_USER_VGA "vhost-user-vga"
+
+#define VHOST_USER_VGA(obj)                                \
+    OBJECT_CHECK(VhostUserVGA, (obj), TYPE_VHOST_USER_VGA)
+
+typedef struct VhostUserVGA {
+    VirtIOVGABase parent_obj;
+
+    VhostUserGPU vdev;
+} VhostUserVGA;
+
+static void vhost_user_vga_inst_initfn(Object *obj)
+{
+    VhostUserVGA *dev = VHOST_USER_VGA(obj);
+
+    virtio_instance_init_common(obj, &dev->vdev, sizeof(dev->vdev),
+                                TYPE_VHOST_USER_GPU);
+
+    VIRTIO_VGA_BASE(dev)->vgpu = VIRTIO_GPU_BASE(&dev->vdev);
+
+    object_property_add_alias(obj, "chardev",
+                              OBJECT(&dev->vdev), "chardev",
+                              &error_abort);
+}
+
+static const VirtioPCIDeviceTypeInfo vhost_user_vga_info = {
+    .generic_name  = TYPE_VHOST_USER_VGA,
+    .parent        = TYPE_VIRTIO_VGA_BASE,
+    .instance_size = sizeof(struct VhostUserVGA),
+    .instance_init = vhost_user_vga_inst_initfn,
+};
+
+static void vhost_user_vga_register_types(void)
+{
+    virtio_pci_types_register(&vhost_user_vga_info);
+}
+
+type_init(vhost_user_vga_register_types)

hw/display/virtio-gpu-pci.c

@@ -16,22 +16,7 @@
 #include "hw/pci/pci.h"
 #include "hw/virtio/virtio.h"
 #include "hw/virtio/virtio-bus.h"
-#include "hw/virtio/virtio-pci.h"
-#include "hw/virtio/virtio-gpu.h"
-
-typedef struct VirtIOGPUPCIBase VirtIOGPUPCIBase;
-
-/*
- * virtio-gpu-pci-base: This extends VirtioPCIProxy.
- */
-#define TYPE_VIRTIO_GPU_PCI_BASE "virtio-gpu-pci-base"
-#define VIRTIO_GPU_PCI_BASE(obj) \
-        OBJECT_CHECK(VirtIOGPUPCIBase, (obj), TYPE_VIRTIO_GPU_PCI_BASE)
-
-struct VirtIOGPUPCIBase {
-    VirtIOPCIProxy parent_obj;
-    VirtIOGPUBase *vgpu;
-};
+#include "hw/virtio/virtio-gpu-pci.h"
 
 static Property virtio_gpu_pci_base_properties[] = {
     DEFINE_VIRTIO_GPU_PCI_PROPERTIES(VirtIOPCIProxy),

hw/display/virtio-vga.h

@@ -1,7 +1,7 @@
 #ifndef VIRTIO_VGA_H_
 #define VIRTIO_VGA_H_
 
-#include "hw/virtio/virtio-pci.h"
+#include "hw/virtio/virtio-gpu-pci.h"
 #include "vga_int.h"
 
 /*

include/hw/virtio/virtio-gpu-pci.h

@@ -0,0 +1,40 @@
+/*
+ * Virtio GPU PCI Device
+ *
+ * Copyright Red Hat, Inc. 2013-2014
+ *
+ * Authors:
+ *     Dave Airlie <airlied@redhat.com>
+ *     Gerd Hoffmann <kraxel@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef HW_VIRTIO_GPU_PCI_H
+#define HW_VIRTIO_GPU_PCI_H
+
+#include "hw/virtio/virtio-pci.h"
+#include "hw/virtio/virtio-gpu.h"
+
+typedef struct VirtIOGPUPCIBase VirtIOGPUPCIBase;
+
+/*
+ * virtio-gpu-pci-base: This extends VirtioPCIProxy.
+ */
+#define TYPE_VIRTIO_GPU_PCI_BASE "virtio-gpu-pci-base"
+#define VIRTIO_GPU_PCI_BASE(obj)                                    \
+    OBJECT_CHECK(VirtIOGPUPCIBase, (obj), TYPE_VIRTIO_GPU_PCI_BASE)
+
+struct VirtIOGPUPCIBase {
+    VirtIOPCIProxy parent_obj;
+    VirtIOGPUBase *vgpu;
+};
+
+/* to share between PCI and VGA */
+#define DEFINE_VIRTIO_GPU_PCI_PROPERTIES(_state)                \
+    DEFINE_PROP_BIT("ioeventfd", _state, flags,                 \
+                    VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT, false),  \
+        DEFINE_PROP_UINT32("vectors", _state, nvectors, 3)
+
+#endif /* HW_VIRTIO_GPU_PCI_H */

include/hw/virtio/virtio-gpu.h

@@ -19,6 +19,7 @@
 #include "ui/console.h"
 #include "hw/virtio/virtio.h"
 #include "qemu/log.h"
+#include "sysemu/vhost-user-backend.h"
 
 #include "standard-headers/linux/virtio_gpu.h"
 
@@ -34,6 +35,8 @@
 #define VIRTIO_GPU(obj)                                        \
         OBJECT_CHECK(VirtIOGPU, (obj), TYPE_VIRTIO_GPU)
 
+#define TYPE_VHOST_USER_GPU "vhost-user-gpu"
+
 #define VIRTIO_ID_GPU 16
 
 struct virtio_gpu_simple_resource {
@@ -157,13 +160,17 @@ typedef struct VirtIOGPU {
     } stats;
 } VirtIOGPU;
 
-extern const GraphicHwOps virtio_gpu_ops;
+typedef struct VhostUserGPU {
+    VirtIOGPUBase parent_obj;
 
-/* to share between PCI and VGA */
-#define DEFINE_VIRTIO_GPU_PCI_PROPERTIES(_state)               \
-    DEFINE_PROP_BIT("ioeventfd", _state, flags,                \
-                    VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT, false), \
-    DEFINE_PROP_UINT32("vectors", _state, nvectors, 3)
+    VhostUserBackend *vhost;
+    int vhost_gpu_fd; /* closed by the chardev */
+    CharBackend vhost_chr;
+    QemuDmaBuf dmabuf[VIRTIO_GPU_MAX_SCANOUTS];
+    bool backend_blocked;
+} VhostUserGPU;
+
+extern const GraphicHwOps virtio_gpu_ops;
 
 #define VIRTIO_GPU_FILL_CMD(out) do {                                   \
         size_t s;                                                       \

vl.c

@@ -239,6 +239,7 @@ static struct {
     { .driver = "qxl-vga",              .flag = &default_vga       },
     { .driver = "virtio-vga",           .flag = &default_vga       },
     { .driver = "ati-vga",              .flag = &default_vga       },
+    { .driver = "vhost-user-vga",       .flag = &default_vga       },
 };
 
 static QemuOptsList qemu_rtc_opts = {