iris: Use Intel GPU for resource allocation in the case of kmsro

Now that our virtio-GPU supports importing external buffers, it's
possible to allocate buffers in Intel GPU and share it with virtio-GPU.
In addition, we'd like to share buffers in dGPU local memory to achieve
zero-copy when scanning out with dGPU, making this change a
prerequisite.

Tracked-On: OAM-127438
Signed-off-by: Weifeng Liu <[email protected]>
(cherry picked from commit 2988b19)
Signed-off-by: Lina Sun <[email protected]>

src/gallium/drivers/iris/iris_resource.c

@@ -1130,43 +1130,6 @@ iris_resource_create_for_buffer(struct pipe_screen *pscreen,
    return &res->base.b;
 }
 
-static struct pipe_resource *
-iris_resource_create_renderonly(struct pipe_screen *pscreen,
-                                const struct pipe_resource *templ)
-{
-   struct iris_screen *screen = (struct iris_screen *)pscreen;
-   struct pipe_resource scanout_templat = *templ;
-   struct renderonly_scanout *scanout;
-   struct winsys_handle handle;
-   struct pipe_resource *pres;
-
-   if (templ->bind & (PIPE_BIND_RENDER_TARGET |
-                      PIPE_BIND_DEPTH_STENCIL)) {
-      scanout_templat.width0 = align(templ->width0, 16);
-      scanout_templat.height0 = align(templ->height0, 16);
-   }
-
-   scanout = renderonly_scanout_for_resource(&scanout_templat,
-                                             screen->ro, &handle);
-   if (!scanout)
-      return NULL;
-
-   assert(handle.type == WINSYS_HANDLE_TYPE_FD);
-   pres = pscreen->resource_from_handle(pscreen, templ, &handle,
-                                        PIPE_HANDLE_USAGE_FRAMEBUFFER_WRITE);
-
-   close(handle.handle);
-   if (!pres) {
-      renderonly_scanout_destroy(scanout, screen->ro);
-      return NULL;
-   }
-
-   struct iris_resource *res = (struct iris_resource *)pres;
-   res->scanout = scanout;
-
-   return pres;
-}
-
 static struct pipe_resource *
 iris_resource_create_for_image(struct pipe_screen *pscreen,
                                const struct pipe_resource *templ,
@@ -1176,16 +1139,6 @@ iris_resource_create_for_image(struct pipe_screen *pscreen,
 {
    struct iris_screen *screen = (struct iris_screen *)pscreen;
    const struct intel_device_info *devinfo = screen->devinfo;
-   struct pipe_resource *pres;
-
-   if (screen->ro &&
-       (templ->bind & (PIPE_BIND_DISPLAY_TARGET |
-                       PIPE_BIND_SCANOUT | PIPE_BIND_SHARED))) {
-      pres = iris_resource_create_renderonly(pscreen, templ);
-      if (pres)
-        return pres;
-   }
-
    struct iris_resource *res = iris_alloc_resource(pscreen, templ);
    if (!res)
       return NULL;
@@ -1278,6 +1231,12 @@ iris_resource_create_for_image(struct pipe_screen *pscreen,
       res->base.is_shared = true;
    }
 
+   if (screen->ro &&
+       (templ->bind & (PIPE_BIND_DISPLAY_TARGET |
+                       PIPE_BIND_SCANOUT | PIPE_BIND_SHARED))) {
+      res->scanout = renderonly_scanout_for_resource(&res->base.b, screen->ro, NULL);
+   }
+
    return &res->base.b;
 
 fail:
@@ -1447,6 +1406,17 @@ iris_resource_from_handle(struct pipe_screen *pscreen,
    res->offset = whandle->offset;
    res->surf.row_pitch_B = whandle->stride;
 
+   if (screen->ro) {
+      /* Make sure that renderonly has a handle to our buffer in the
+       * display's fd, so that a later renderonly_get_handle()
+       * returns correct handles or GEM names.
+       */
+      res->scanout =
+              renderonly_create_gpu_import_for_resource(&res->base.b,
+                                                        screen->ro,
+                                                        NULL);
+   }
+
    if (whandle->plane == 0) {
       /* All planes are present. Fill out the main plane resource(s). */
       for (unsigned plane = 0; plane < util_resource_num(templ); plane++) {

src/gallium/winsys/kmsro/drm/kmsro_drm_winsys.c

@@ -123,7 +123,7 @@ struct pipe_screen *kmsro_drm_screen_create(int kms_fd,
 #endif
    } else if (strcmp(render_dev_name, "i915") == 0) {
 #if defined(GALLIUM_IRIS)
-      ro->create_for_resource = renderonly_create_kms_dumb_buffer_for_resource,
+      ro->create_for_resource = renderonly_create_gpu_import_for_resource,
       screen = iris_screen_create_renderonly(ro->gpu_fd, ro, config);
 #endif
    }