[Qemu-devel] [RfC PATCH 5/6] vfio/display: adding region support

[Gerd Hoffmann <kraxel@redhat.com>]

Wire up region-based display.  UNTESTED.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 hw/vfio/pci.h     |  6 ++++
 hw/vfio/display.c | 96 +++++++++++++++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 100 insertions(+), 2 deletions(-)

diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
index 3c1b0a33ab..c03c4b3eb0 100644
--- a/hw/vfio/pci.h
+++ b/hw/vfio/pci.h
@@ -146,6 +146,12 @@ typedef struct VFIOPCIDevice {
     bool no_kvm_intx;
     bool no_kvm_msi;
     bool no_kvm_msix;
+    /* vgpu local display */
+    QemuConsole *display_con;
+    uint32_t region_index;
+    uint32_t region_size;
+    void *region_mmap;
+    DisplaySurface *region_surface;
 } VFIOPCIDevice;
 
 uint32_t vfio_pci_read_config(PCIDevice *pdev, uint32_t addr, int len);
diff --git a/hw/vfio/display.c b/hw/vfio/display.c
index 064ec95f3e..8211bcc6d4 100644
--- a/hw/vfio/display.c
+++ b/hw/vfio/display.c
@@ -18,6 +18,99 @@
 #include "ui/console.h"
 #include "pci.h"
 
+/* ---------------------------------------------------------------------- */
+
+static void vfio_display_region_update(void *opaque)
+{
+    VFIOPCIDevice *vdev = opaque;
+    struct vfio_device_gfx_plane_info plane;
+    struct vfio_region_info *region = NULL;
+    pixman_format_code_t format = PIXMAN_x8r8g8b8;
+    int ret;
+
+    memset(&plane, 0, sizeof(plane));
+    plane.argsz = sizeof(plane);
+    plane.flags = VFIO_GFX_PLANE_TYPE_REGION;
+    ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_QUERY_GFX_PLANE, &plane);
+    if (ret < 0) {
+        fprintf(stderr, "ioctl VFIO_DEVICE_QUERY_GFX_PLANE: %s\n",
+                strerror(errno));
+        return;
+    }
+    if (!plane.drm_format || !plane.size) {
+        return;
+    }
+    format = qemu_drm_format_to_pixman(plane.drm_format);
+
+    if (vdev->region_mmap && vdev->region_index != plane.region_index) {
+        /* region changed */
+        munmap(vdev->region_mmap, vdev->region_size);
+        vdev->region_mmap = NULL;
+        vdev->region_surface = NULL;
+    }
+
+    if (vdev->region_surface &&
+        (surface_width(vdev->region_surface) != plane.width ||
+         surface_height(vdev->region_surface) != plane.height ||
+         surface_format(vdev->region_surface) != format)) {
+        /* size changed */
+        vdev->region_surface = NULL;
+    }
+
+    if (vdev->region_mmap == NULL) {
+        /* mmap region */
+        ret = vfio_get_region_info(&vdev->vbasedev, plane.region_index,
+                                   &region);
+        if (ret != 0) {
+            fprintf(stderr, "%s: vfio_get_region_info(%d): %s\n",
+                    __func__, plane.region_index, strerror(-ret));
+            return;
+        }
+        vdev->region_size = region->size;
+        vdev->region_mmap = mmap(NULL, region->size,
+                                 PROT_READ, MAP_SHARED,
+                                 vdev->vbasedev.fd,
+                                 region->offset);
+        if (vdev->region_mmap == MAP_FAILED) {
+            fprintf(stderr, "%s: mmap region %d: %s\n", __func__,
+                    plane.region_index, strerror(errno));
+            vdev->region_mmap = NULL;
+            g_free(region);
+            return;
+        }
+        g_free(region);
+    }
+
+    if (vdev->region_surface == NULL) {
+        /* create surface */
+        vdev->region_surface = qemu_create_displaysurface_from
+            (plane.width, plane.height, format,
+             plane.stride, vdev->region_mmap);
+        dpy_gfx_replace_surface(vdev->display_con, vdev->region_surface);
+    }
+
+    /* full screen update */
+    dpy_gfx_update(vdev->display_con, 0, 0,
+                   surface_width(vdev->region_surface),
+                   surface_height(vdev->region_surface));
+
+}
+
+static const GraphicHwOps vfio_display_region_ops = {
+    .gfx_update = vfio_display_region_update,
+};
+
+static int vfio_display_region_init(VFIOPCIDevice *vdev, Error **errp)
+{
+    vdev->display_con = graphic_console_init(DEVICE(vdev), 0,
+                                             &vfio_display_region_ops,
+                                             vdev);
+    /* TODO: disable hotplug (there is no graphic_console_close) */
+    return 0;
+}
+
+/* ---------------------------------------------------------------------- */
+
 int vfio_display_probe(VFIOPCIDevice *vdev, Error **errp)
 {
     struct vfio_device_gfx_plane_info probe;
@@ -37,8 +130,7 @@ int vfio_display_probe(VFIOPCIDevice *vdev, Error **errp)
     probe.flags = VFIO_GFX_PLANE_TYPE_PROBE | VFIO_GFX_PLANE_TYPE_REGION;
     ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_QUERY_GFX_PLANE, &probe);
     if (ret == 0) {
-        error_setg(errp, "vfio-display: region support not implemented yet");
-        return -1;
+        return vfio_display_region_init(vdev, errp);
     }
 
     error_setg(errp, "vfio: device doesn't support any (known) display method");
-- 
2.9.3