contrib: add vhost-user-gpu

Add a vhost-user gpu backend, based on virtio-gpu/3d device. It is
associated with a vhost-user-gpu device.

Various TODO and nice to have items:
- multi-head support
- crash & resume handling
- accelerated rendering/display that avoids the waiting round trips
- edid support

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20190524130946.31736-6-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

MAINTAINERS

@@ -1681,6 +1681,8 @@ M: Marc-André Lureau <marcandre.lureau@redhat.com>
 M: Gerd Hoffmann <kraxel@redhat.com>
 S: Maintained
 F: docs/interop/vhost-user-gpu.rst
+F: contrib/vhost-user-gpu
+F: hw/display/vhost-user-*
 
 Cirrus VGA
 M: Gerd Hoffmann <kraxel@redhat.com>

Makefile

@@ -314,8 +314,20 @@ $(call set-vpath, $(SRC_PATH))
 
 LIBS+=-lz $(LIBS_TOOLS)
 
+vhost-user-json-y =
+HELPERS-y =
+
 HELPERS-$(call land,$(CONFIG_SOFTMMU),$(CONFIG_LINUX)) = qemu-bridge-helper$(EXESUF)
 
+ifdef CONFIG_LINUX
+ifdef CONFIG_VIRGL
+ifdef CONFIG_GBM
+HELPERS-y += vhost-user-gpu$(EXESUF)
+vhost-user-json-y += contrib/vhost-user-gpu/50-qemu-gpu.json
+endif
+endif
+endif
+
 ifdef BUILD_DOCS
 DOCS=qemu-doc.html qemu-doc.txt qemu.1 qemu-img.1 qemu-nbd.8 qemu-ga.8
 DOCS+=docs/interop/qemu-qmp-ref.html docs/interop/qemu-qmp-ref.txt docs/interop/qemu-qmp-ref.7
@@ -409,6 +421,7 @@ dummy := $(call unnest-vars,, \
                 vhost-user-scsi-obj-y \
                 vhost-user-blk-obj-y \
                 vhost-user-input-obj-y \
+                vhost-user-gpu-obj-y \
                 qga-vss-dll-obj-y \
                 block-obj-y \
                 block-obj-m \
@@ -426,7 +439,7 @@ dummy := $(call unnest-vars,, \
 
 include $(SRC_PATH)/tests/Makefile.include
 
-all: $(DOCS) $(if $(BUILD_DOCS),sphinxdocs) $(TOOLS) $(HELPERS-y) recurse-all modules
+all: $(DOCS) $(if $(BUILD_DOCS),sphinxdocs) $(TOOLS) $(HELPERS-y) recurse-all modules $(vhost-user-json-y)
 
 qemu-version.h: FORCE
 	$(call quiet-command, \
@@ -619,6 +632,9 @@ rdmacm-mux$(EXESUF): LIBS += "-libumad"
 rdmacm-mux$(EXESUF): $(rdmacm-mux-obj-y) $(COMMON_LDADDS)
 	$(call LINK, $^)
 
+vhost-user-gpu$(EXESUF): $(vhost-user-gpu-obj-y) $(libvhost-user-obj-y) libqemuutil.a libqemustub.a
+	$(call LINK, $^)
+
 ifdef CONFIG_VHOST_USER_INPUT
 ifdef CONFIG_LINUX
 vhost-user-input$(EXESUF): $(vhost-user-input-obj-y) libvhost-user.a libqemuutil.a
@@ -827,6 +843,12 @@ endif
 ifneq ($(HELPERS-y),)
 	$(call install-prog,$(HELPERS-y),$(DESTDIR)$(libexecdir))
 endif
+ifneq ($(vhost-user-json-y),)
+	$(INSTALL_DIR) "$(DESTDIR)$(qemu_datadir)/vhost-user/"
+	for x in $(vhost-user-json-y); do \
+		$(INSTALL_DATA) $$x "$(DESTDIR)$(qemu_datadir)/vhost-user/"; \
+	done
+endif
 ifdef CONFIG_TRACE_SYSTEMTAP
 	$(INSTALL_PROG) "scripts/qemu-trace-stap" $(DESTDIR)$(bindir)
 endif

Makefile.objs

@@ -123,6 +123,7 @@ vhost-user-scsi-obj-y = contrib/vhost-user-scsi/
 vhost-user-blk-obj-y = contrib/vhost-user-blk/
 rdmacm-mux-obj-y = contrib/rdmacm-mux/
 vhost-user-input-obj-y = contrib/vhost-user-input/
+vhost-user-gpu-obj-y = contrib/vhost-user-gpu/
 
 ######################################################################
 trace-events-subdirs =

configure

@@ -4099,6 +4099,13 @@ libs_softmmu="$libs_softmmu $fdt_libs"
 ##########################################
 # opengl probe (for sdl2, gtk, milkymist-tmu2)
 
+gbm="no"
+if $pkg_config gbm; then
+    gbm_cflags="$($pkg_config --cflags gbm)"
+    gbm_libs="$($pkg_config --libs gbm)"
+    gbm="yes"
+fi
+
 if test "$opengl" != "no" ; then
   opengl_pkgs="epoxy gbm"
   if $pkg_config $opengl_pkgs; then
@@ -6964,6 +6971,13 @@ if test "$opengl" = "yes" ; then
   fi
 fi
 
+if test "$gbm" = "yes" ; then
+    echo "CONFIG_GBM=y" >> $config_host_mak
+    echo "GBM_LIBS=$gbm_libs" >> $config_host_mak
+    echo "GBM_CFLAGS=$gbm_cflags" >> $config_host_mak
+fi
+
+
 if test "$malloc_trim" = "yes" ; then
   echo "CONFIG_MALLOC_TRIM=y" >> $config_host_mak
 fi
@@ -7859,6 +7873,9 @@ echo "QEMU_CFLAGS+=$cflags" >> $config_target_mak
 
 done # for target in $targets
 
+echo "PIXMAN_CFLAGS=$pixman_cflags" >> $config_host_mak
+echo "PIXMAN_LIBS=$pixman_libs" >> $config_host_mak
+
 if test -n "$enabled_cross_compilers"; then
     echo
     echo "NOTE: cross-compilers enabled: $enabled_cross_compilers"

contrib/vhost-user-gpu/50-qemu-gpu.json.in

@@ -0,0 +1,5 @@
+{
+  "description": "QEMU vhost-user-gpu",
+  "type": "gpu",
+  "binary": "@libexecdir@/vhost-user-gpu",
+}

contrib/vhost-user-gpu/Makefile.objs

@@ -0,0 +1,10 @@
+vhost-user-gpu-obj-y = main.o virgl.o vugbm.o
+
+main.o-cflags := $(PIXMAN_CFLAGS) $(GBM_CFLAGS)
+main.o-libs := $(PIXMAN_LIBS)
+
+virgl.o-cflags := $(VIRGL_CFLAGS) $(GBM_CFLAGS)
+virgl.o-libs := $(VIRGL_LIBS)
+
+vugbm.o-cflags := $(GBM_CFLAGS)
+vugbm.o-libs := $(GBM_LIBS)

contrib/vhost-user-gpu/virgl.h

@@ -0,0 +1,25 @@
+/*
+ * Virtio vhost-user GPU Device
+ *
+ * Copyright Red Hat, Inc. 2013-2018
+ *
+ * Authors:
+ *     Dave Airlie <airlied@redhat.com>
+ *     Gerd Hoffmann <kraxel@redhat.com>
+ *     Marc-André Lureau <marcandre.lureau@redhat.com>
+ *
+ * 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 VUGPU_VIRGL_H_
+#define VUGPU_VIRGL_H_
+
+#include "vugpu.h"
+
+bool vg_virgl_init(VuGpu *g);
+uint32_t vg_virgl_get_num_capsets(void);
+void vg_virgl_process_cmd(VuGpu *vg, struct virtio_gpu_ctrl_command *cmd);
+void vg_virgl_update_cursor_data(VuGpu *g, uint32_t resource_id,
+                                 gpointer data);
+
+#endif

contrib/vhost-user-gpu/vugbm.c

@@ -0,0 +1,328 @@
+/*
+ * Virtio vhost-user GPU Device
+ *
+ * DRM helpers
+ *
+ * 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 "vugbm.h"
+
+static bool
+mem_alloc_bo(struct vugbm_buffer *buf)
+{
+    buf->mmap = g_malloc(buf->width * buf->height * 4);
+    buf->stride = buf->width * 4;
+    return true;
+}
+
+static void
+mem_free_bo(struct vugbm_buffer *buf)
+{
+    g_free(buf->mmap);
+}
+
+static bool
+mem_map_bo(struct vugbm_buffer *buf)
+{
+    return buf->mmap != NULL;
+}
+
+static void
+mem_unmap_bo(struct vugbm_buffer *buf)
+{
+}
+
+static void
+mem_device_destroy(struct vugbm_device *dev)
+{
+}
+
+#ifdef CONFIG_MEMFD
+struct udmabuf_create {
+        uint32_t memfd;
+        uint32_t flags;
+        uint64_t offset;
+        uint64_t size;
+};
+
+#define UDMABUF_CREATE _IOW('u', 0x42, struct udmabuf_create)
+
+static size_t
+udmabuf_get_size(struct vugbm_buffer *buf)
+{
+    return ROUND_UP(buf->width * buf->height * 4, getpagesize());
+}
+
+static bool
+udmabuf_alloc_bo(struct vugbm_buffer *buf)
+{
+    int ret;
+
+    buf->memfd = memfd_create("udmabuf-bo", MFD_ALLOW_SEALING);
+    if (buf->memfd < 0) {
+        return false;
+    }
+
+    ret = ftruncate(buf->memfd, udmabuf_get_size(buf));
+    if (ret < 0) {
+        close(buf->memfd);
+        return false;
+    }
+
+    ret = fcntl(buf->memfd, F_ADD_SEALS, F_SEAL_SHRINK);
+    if (ret < 0) {
+        close(buf->memfd);
+        return false;
+    }
+
+    buf->stride = buf->width * 4;
+
+    return true;
+}
+
+static void
+udmabuf_free_bo(struct vugbm_buffer *buf)
+{
+    close(buf->memfd);
+}
+
+static bool
+udmabuf_map_bo(struct vugbm_buffer *buf)
+{
+    buf->mmap = mmap(NULL, udmabuf_get_size(buf),
+                     PROT_READ | PROT_WRITE, MAP_SHARED, buf->memfd, 0);
+    if (buf->mmap == MAP_FAILED) {
+        return false;
+    }
+
+    return true;
+}
+
+static bool
+udmabuf_get_fd(struct vugbm_buffer *buf, int *fd)
+{
+    struct udmabuf_create create = {
+        .memfd = buf->memfd,
+        .offset = 0,
+        .size = udmabuf_get_size(buf),
+    };
+
+    *fd = ioctl(buf->dev->fd, UDMABUF_CREATE, &create);
+
+    return *fd >= 0;
+}
+
+static void
+udmabuf_unmap_bo(struct vugbm_buffer *buf)
+{
+    munmap(buf->mmap, udmabuf_get_size(buf));
+}
+
+static void
+udmabuf_device_destroy(struct vugbm_device *dev)
+{
+    close(dev->fd);
+}
+#endif
+
+#ifdef CONFIG_GBM
+static bool
+alloc_bo(struct vugbm_buffer *buf)
+{
+    struct gbm_device *dev = buf->dev->dev;
+
+    assert(!buf->bo);
+
+    buf->bo = gbm_bo_create(dev, buf->width, buf->height,
+                            buf->format,
+                            GBM_BO_USE_RENDERING | GBM_BO_USE_LINEAR);
+
+    if (buf->bo) {
+        buf->stride = gbm_bo_get_stride(buf->bo);
+        return true;
+    }
+
+    return false;
+}
+
+static void
+free_bo(struct vugbm_buffer *buf)
+{
+    gbm_bo_destroy(buf->bo);
+}
+
+static bool
+map_bo(struct vugbm_buffer *buf)
+{
+    uint32_t stride;
+
+    buf->mmap = gbm_bo_map(buf->bo, 0, 0, buf->width, buf->height,
+                           GBM_BO_TRANSFER_READ_WRITE, &stride,
+                           &buf->mmap_data);
+
+    assert(stride == buf->stride);
+
+    return buf->mmap != NULL;
+}
+
+static void
+unmap_bo(struct vugbm_buffer *buf)
+{
+    gbm_bo_unmap(buf->bo, buf->mmap_data);
+}
+
+static bool
+get_fd(struct vugbm_buffer *buf, int *fd)
+{
+    *fd = gbm_bo_get_fd(buf->bo);
+
+    return *fd >= 0;
+}
+
+static void
+device_destroy(struct vugbm_device *dev)
+{
+    gbm_device_destroy(dev->dev);
+}
+#endif
+
+void
+vugbm_device_destroy(struct vugbm_device *dev)
+{
+    if (!dev->inited) {
+        return;
+    }
+
+    dev->device_destroy(dev);
+}
+
+bool
+vugbm_device_init(struct vugbm_device *dev, int fd)
+{
+    dev->fd = fd;
+
+#ifdef CONFIG_GBM
+    dev->dev = gbm_create_device(fd);
+#endif
+
+    if (0) {
+        /* nothing */
+    }
+#ifdef CONFIG_GBM
+    else if (dev->dev != NULL) {
+        dev->alloc_bo = alloc_bo;
+        dev->free_bo = free_bo;
+        dev->get_fd = get_fd;
+        dev->map_bo = map_bo;
+        dev->unmap_bo = unmap_bo;
+        dev->device_destroy = device_destroy;
+    }
+#endif
+#ifdef CONFIG_MEMFD
+    else if (g_file_test("/dev/udmabuf", G_FILE_TEST_EXISTS)) {
+        dev->fd = open("/dev/udmabuf", O_RDWR);
+        if (dev->fd < 0) {
+            return false;
+        }
+        g_debug("Using experimental udmabuf backend");
+        dev->alloc_bo = udmabuf_alloc_bo;
+        dev->free_bo = udmabuf_free_bo;
+        dev->get_fd = udmabuf_get_fd;
+        dev->map_bo = udmabuf_map_bo;
+        dev->unmap_bo = udmabuf_unmap_bo;
+        dev->device_destroy = udmabuf_device_destroy;
+    }
+#endif
+    else {
+        g_debug("Using mem fallback");
+        dev->alloc_bo = mem_alloc_bo;
+        dev->free_bo = mem_free_bo;
+        dev->map_bo = mem_map_bo;
+        dev->unmap_bo = mem_unmap_bo;
+        dev->device_destroy = mem_device_destroy;
+        return false;
+    }
+
+    dev->inited = true;
+    return true;
+}
+
+static bool
+vugbm_buffer_map(struct vugbm_buffer *buf)
+{
+    struct vugbm_device *dev = buf->dev;
+
+    return dev->map_bo(buf);
+}
+
+static void
+vugbm_buffer_unmap(struct vugbm_buffer *buf)
+{
+    struct vugbm_device *dev = buf->dev;
+
+    dev->unmap_bo(buf);
+}
+
+bool
+vugbm_buffer_can_get_dmabuf_fd(struct vugbm_buffer *buffer)
+{
+    if (!buffer->dev->get_fd) {
+        return false;
+    }
+
+    return true;
+}
+
+bool
+vugbm_buffer_get_dmabuf_fd(struct vugbm_buffer *buffer, int *fd)
+{
+    if (!vugbm_buffer_can_get_dmabuf_fd(buffer) ||
+        !buffer->dev->get_fd(buffer, fd)) {
+        g_warning("Failed to get dmabuf");
+        return false;
+    }
+
+    if (*fd < 0) {
+        g_warning("error: dmabuf_fd < 0");
+        return false;
+    }
+
+    return true;
+}
+
+bool
+vugbm_buffer_create(struct vugbm_buffer *buffer, struct vugbm_device *dev,
+                    uint32_t width, uint32_t height)
+{
+    buffer->dev = dev;
+    buffer->width = width;
+    buffer->height = height;
+    buffer->format = GBM_FORMAT_XRGB8888;
+    buffer->stride = 0; /* modified during alloc */
+    if (!dev->alloc_bo(buffer)) {
+        g_warning("alloc_bo failed");
+        return false;
+    }
+
+    if (!vugbm_buffer_map(buffer)) {
+        g_warning("map_bo failed");
+        goto err;
+    }
+
+    return true;
+
+err:
+    dev->free_bo(buffer);
+    return false;
+}
+
+void
+vugbm_buffer_destroy(struct vugbm_buffer *buffer)
+{
+    struct vugbm_device *dev = buffer->dev;
+
+    vugbm_buffer_unmap(buffer);
+    dev->free_bo(buffer);
+}

contrib/vhost-user-gpu/vugbm.h

@@ -0,0 +1,67 @@
+/*
+ * Virtio vhost-user GPU Device
+ *
+ * GBM helpers
+ *
+ * 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 VHOST_USER_GPU_GBM_H
+#define VHOST_USER_GPU_GBM_H
+
+#include "qemu/osdep.h"
+
+#ifdef CONFIG_MEMFD
+#include <sys/mman.h>
+#include <sys/ioctl.h>
+#endif
+
+#ifdef CONFIG_GBM
+#include <gbm.h>
+#endif
+
+struct vugbm_buffer;
+
+struct vugbm_device {
+    bool inited;
+    int fd;
+#ifdef CONFIG_GBM
+    struct gbm_device *dev;
+#endif
+
+    bool (*alloc_bo)(struct vugbm_buffer *buf);
+    void (*free_bo)(struct vugbm_buffer *buf);
+    bool (*get_fd)(struct vugbm_buffer *buf, int *fd);
+    bool (*map_bo)(struct vugbm_buffer *buf);
+    void (*unmap_bo)(struct vugbm_buffer *buf);
+    void (*device_destroy)(struct vugbm_device *dev);
+};
+
+struct vugbm_buffer {
+    struct vugbm_device *dev;
+
+#ifdef CONFIG_MEMFD
+    int memfd;
+#endif
+#ifdef CONFIG_GBM
+    struct gbm_bo *bo;
+    void *mmap_data;
+#endif
+
+    uint8_t *mmap;
+    uint32_t width;
+    uint32_t height;
+    uint32_t stride;
+    uint32_t format;
+};
+
+bool vugbm_device_init(struct vugbm_device *dev, int fd);
+void vugbm_device_destroy(struct vugbm_device *dev);
+
+bool vugbm_buffer_create(struct vugbm_buffer *buffer, struct vugbm_device *dev,
+                         uint32_t width, uint32_t height);
+bool vugbm_buffer_can_get_dmabuf_fd(struct vugbm_buffer *buffer);
+bool vugbm_buffer_get_dmabuf_fd(struct vugbm_buffer *buffer, int *fd);
+void vugbm_buffer_destroy(struct vugbm_buffer *buffer);
+
+#endif

contrib/vhost-user-gpu/vugpu.h

@@ -0,0 +1,177 @@
+/*
+ * Virtio vhost-user GPU Device
+ *
+ * Copyright Red Hat, Inc. 2013-2018
+ *
+ * Authors:
+ *     Dave Airlie <airlied@redhat.com>
+ *     Gerd Hoffmann <kraxel@redhat.com>
+ *     Marc-André Lureau <marcandre.lureau@redhat.com>
+ *
+ * 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 VUGPU_H_
+#define VUGPU_H_
+
+#include "qemu/osdep.h"
+
+#include "contrib/libvhost-user/libvhost-user-glib.h"
+#include "standard-headers/linux/virtio_gpu.h"
+
+#include "qemu/queue.h"
+#include "qemu/iov.h"
+#include "qemu/bswap.h"
+#include "vugbm.h"
+
+typedef enum VhostUserGpuRequest {
+    VHOST_USER_GPU_NONE = 0,
+    VHOST_USER_GPU_GET_PROTOCOL_FEATURES,
+    VHOST_USER_GPU_SET_PROTOCOL_FEATURES,
+    VHOST_USER_GPU_GET_DISPLAY_INFO,
+    VHOST_USER_GPU_CURSOR_POS,
+    VHOST_USER_GPU_CURSOR_POS_HIDE,
+    VHOST_USER_GPU_CURSOR_UPDATE,
+    VHOST_USER_GPU_SCANOUT,
+    VHOST_USER_GPU_UPDATE,
+    VHOST_USER_GPU_DMABUF_SCANOUT,
+    VHOST_USER_GPU_DMABUF_UPDATE,
+} VhostUserGpuRequest;
+
+typedef struct VhostUserGpuDisplayInfoReply {
+    struct virtio_gpu_resp_display_info info;
+} VhostUserGpuDisplayInfoReply;
+
+typedef struct VhostUserGpuCursorPos {
+    uint32_t scanout_id;
+    uint32_t x;
+    uint32_t y;
+} QEMU_PACKED VhostUserGpuCursorPos;
+
+typedef struct VhostUserGpuCursorUpdate {
+    VhostUserGpuCursorPos pos;
+    uint32_t hot_x;
+    uint32_t hot_y;
+    uint32_t data[64 * 64];
+} QEMU_PACKED VhostUserGpuCursorUpdate;
+
+typedef struct VhostUserGpuScanout {
+    uint32_t scanout_id;
+    uint32_t width;
+    uint32_t height;
+} QEMU_PACKED VhostUserGpuScanout;
+
+typedef struct VhostUserGpuUpdate {
+    uint32_t scanout_id;
+    uint32_t x;
+    uint32_t y;
+    uint32_t width;
+    uint32_t height;
+    uint8_t data[];
+} QEMU_PACKED VhostUserGpuUpdate;
+
+typedef struct VhostUserGpuDMABUFScanout {
+    uint32_t scanout_id;
+    uint32_t x;
+    uint32_t y;
+    uint32_t width;
+    uint32_t height;
+    uint32_t fd_width;
+    uint32_t fd_height;
+    uint32_t fd_stride;
+    uint32_t fd_flags;
+    int fd_drm_fourcc;
+} QEMU_PACKED VhostUserGpuDMABUFScanout;
+
+typedef struct VhostUserGpuMsg {
+    uint32_t request; /* VhostUserGpuRequest */
+    uint32_t flags;
+    uint32_t size; /* the following payload size */
+    union {
+        VhostUserGpuCursorPos cursor_pos;
+        VhostUserGpuCursorUpdate cursor_update;
+        VhostUserGpuScanout scanout;
+        VhostUserGpuUpdate update;
+        VhostUserGpuDMABUFScanout dmabuf_scanout;
+        struct virtio_gpu_resp_display_info display_info;
+        uint64_t u64;
+    } payload;
+} QEMU_PACKED VhostUserGpuMsg;
+
+static VhostUserGpuMsg m __attribute__ ((unused));
+#define VHOST_USER_GPU_HDR_SIZE \
+    (sizeof(m.request) + sizeof(m.flags) + sizeof(m.size))
+
+#define VHOST_USER_GPU_MSG_FLAG_REPLY 0x4
+
+struct virtio_gpu_scanout {
+    uint32_t width, height;
+    int x, y;
+    int invalidate;
+    uint32_t resource_id;
+};
+
+typedef struct VuGpu {
+    VugDev dev;
+    struct virtio_gpu_config virtio_config;
+    struct vugbm_device gdev;
+    int sock_fd;
+    int drm_rnode_fd;
+    GSource *renderer_source;
+    guint wait_ok;
+
+    bool virgl;
+    bool virgl_inited;
+    uint32_t inflight;
+
+    struct virtio_gpu_scanout scanout[VIRTIO_GPU_MAX_SCANOUTS];
+    QTAILQ_HEAD(, virtio_gpu_simple_resource) reslist;
+    QTAILQ_HEAD(, virtio_gpu_ctrl_command) fenceq;
+} VuGpu;
+
+struct virtio_gpu_ctrl_command {
+    VuVirtqElement elem;
+    VuVirtq *vq;
+    struct virtio_gpu_ctrl_hdr cmd_hdr;
+    uint32_t error;
+    bool finished;
+    QTAILQ_ENTRY(virtio_gpu_ctrl_command) next;
+};
+
+#define VUGPU_FILL_CMD(out) do {                                \
+        size_t s;                                               \
+        s = iov_to_buf(cmd->elem.out_sg, cmd->elem.out_num, 0,  \
+                       &out, sizeof(out));                      \
+        if (s != sizeof(out)) {                                 \
+            g_critical("%s: command size incorrect %zu vs %zu", \
+                       __func__, s, sizeof(out));               \
+            return;                                             \
+        }                                                       \
+    } while (0)
+
+
+void    vg_ctrl_response(VuGpu *g,
+                         struct virtio_gpu_ctrl_command *cmd,
+                         struct virtio_gpu_ctrl_hdr *resp,
+                         size_t resp_len);
+
+void    vg_ctrl_response_nodata(VuGpu *g,
+                                struct virtio_gpu_ctrl_command *cmd,
+                                enum virtio_gpu_ctrl_type type);
+
+int     vg_create_mapping_iov(VuGpu *g,
+                              struct virtio_gpu_resource_attach_backing *ab,
+                              struct virtio_gpu_ctrl_command *cmd,
+                              struct iovec **iov);
+
+void    vg_get_display_info(VuGpu *vg, struct virtio_gpu_ctrl_command *cmd);
+
+void    vg_wait_ok(VuGpu *g);
+
+void    vg_send_msg(VuGpu *g, const VhostUserGpuMsg *msg, int fd);
+
+bool    vg_recv_msg(VuGpu *g, uint32_t expect_req, uint32_t expect_size,
+                    gpointer payload);
+
+
+#endif

rules.mak

@@ -144,7 +144,7 @@ cc-option = $(if $(shell $(CC) $1 $2 -S -o /dev/null -xc /dev/null \
 cc-c-option = $(if $(shell $(CC) $1 $2 -c -o /dev/null -xc /dev/null \
                 >/dev/null 2>&1 && echo OK), $2, $3)
 
-VPATH_SUFFIXES = %.c %.h %.S %.cc %.cpp %.m %.mak %.texi %.sh %.rc Kconfig%
+VPATH_SUFFIXES = %.c %.h %.S %.cc %.cpp %.m %.mak %.texi %.sh %.rc Kconfig% %.json.in
 set-vpath = $(if $1,$(foreach PATTERN,$(VPATH_SUFFIXES),$(eval vpath $(PATTERN) $1)))
 
 # install-prog list, dir
@@ -392,3 +392,10 @@ TEXI2MAN = $(call quiet-command, \
 	$(call TEXI2MAN)
 %.8:
 	$(call TEXI2MAN)
+
+GEN_SUBST = $(call quiet-command, \
+	sed -e "s!@libexecdir@!$(libexecdir)!g" < $< > $@, \
+	"GEN","$@")
+
+%.json: %.json.in
+	$(call GEN_SUBST)