vrend: add support for exporting egl fences

Acked-by: Gert Wollny <gert.wollny@collabora.com>

src/virglrenderer.c

@@ -763,3 +763,9 @@ virgl_renderer_resource_export_blob(uint32_t res_id, uint32_t *fd_type, int *fd)
 
    return 0;
 }
+
+int
+virgl_renderer_export_fence(uint32_t client_fence_id, uint32_t *fd)
+{
+   return vrend_renderer_export_fence(client_fence_id, fd);
+}

src/virglrenderer.h

@@ -297,6 +297,9 @@ VIRGL_EXPORT int virgl_renderer_resource_get_map_info(uint32_t res_handle, uint3
 VIRGL_EXPORT int
 virgl_renderer_resource_export_blob(uint32_t res_id, uint32_t *fd_type, int *fd);
 
+VIRGL_EXPORT int
+virgl_renderer_export_fence(uint32_t client_fence_id, uint32_t *fd);
+
 #endif /* VIRGL_RENDERER_UNSTABLE_APIS */
 
 #endif

src/vrend_renderer.c

@@ -10645,3 +10645,55 @@ int vrend_renderer_resource_unmap(struct pipe_resource *pres)
    glBindBufferARB(res->target, 0);
    return 0;
 }
+
+int vrend_renderer_export_fence(uint32_t fence_id, int* out_fd) {
+#ifdef HAVE_EPOXY_EGL_H
+   if (!vrend_state.use_egl_fence) {
+      return -EINVAL;
+   }
+
+   if (vrend_state.sync_thread)
+      pipe_mutex_lock(vrend_state.fence_mutex);
+
+   struct vrend_fence *fence = NULL;
+   struct vrend_fence *iter;
+   uint32_t min_fence_id = UINT_MAX;
+
+   if (!LIST_IS_EMPTY(&vrend_state.fence_list)) {
+      min_fence_id = LIST_ENTRY(struct vrend_fence, vrend_state.fence_list.next, fences)->fence_id;
+   } else if (!LIST_IS_EMPTY(&vrend_state.fence_wait_list)) {
+      min_fence_id =
+            LIST_ENTRY(struct vrend_fence, vrend_state.fence_wait_list.next, fences)->fence_id;
+   }
+
+   if (fence_id < min_fence_id) {
+      if (vrend_state.sync_thread)
+         pipe_mutex_unlock(vrend_state.fence_mutex);
+      return virgl_egl_export_signaled_fence(egl, out_fd) ? 0 : -EINVAL;
+   }
+
+   LIST_FOR_EACH_ENTRY(iter, &vrend_state.fence_list, fences) {
+      if (iter->fence_id == fence_id) {
+         fence = iter;
+         break;
+      }
+   }
+
+   if (!fence) {
+      LIST_FOR_EACH_ENTRY(iter, &vrend_state.fence_wait_list, fences) {
+         if (iter->fence_id == fence_id) {
+            fence = iter;
+            break;
+         }
+      }
+   }
+
+   if (vrend_state.sync_thread)
+      pipe_mutex_unlock(vrend_state.fence_mutex);
+
+   if (fence && virgl_egl_export_fence(egl, fence->eglsyncobj, out_fd)) {
+      return 0;
+   }
+#endif
+   return -EINVAL;
+}

src/vrend_renderer.h

@@ -347,6 +347,8 @@ int vrend_renderer_create_fence(int client_fence_id, uint32_t ctx_id);
 
 void vrend_renderer_check_fences(void);
 
+int vrend_renderer_export_fence(uint32_t fence_id, int* out_fd);
+
 bool vrend_hw_switch_context(struct vrend_context *ctx, bool now);
 uint32_t vrend_renderer_object_insert(struct vrend_context *ctx, void *data,
                                       uint32_t handle, enum virgl_object_type type);

src/vrend_winsys_egl.c

@@ -74,6 +74,7 @@ struct virgl_egl {
    EGLConfig egl_conf;
    EGLContext egl_ctx;
    uint32_t extension_bits;
+   EGLSyncKHR signaled_fence;
 };
 
 static bool virgl_egl_has_extension_in_string(const char *haystack, const char *needle)
@@ -236,6 +237,16 @@ struct virgl_egl *virgl_egl_init(struct virgl_gbm *gbm, bool surfaceless, bool g
 
    eglMakeCurrent(egl->egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE,
                   egl->egl_ctx);
+
+   if (virgl_egl_supports_fences(egl)) {
+      egl->signaled_fence = eglCreateSyncKHR(egl->egl_display,
+                                             EGL_SYNC_NATIVE_FENCE_ANDROID, NULL);
+      if (!egl->signaled_fence) {
+         vrend_printf("Failed to create signaled fence");
+         goto fail;
+      }
+   }
+
    return egl;
 
  fail:
@@ -245,6 +256,9 @@ struct virgl_egl *virgl_egl_init(struct virgl_gbm *gbm, bool surfaceless, bool g
 
 void virgl_egl_destroy(struct virgl_egl *egl)
 {
+   if (egl->signaled_fence) {
+      eglDestroySyncKHR(egl->egl_display, egl->signaled_fence);
+   }
    eglMakeCurrent(egl->egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE,
                   EGL_NO_CONTEXT);
    eglDestroyContext(egl->egl_display, egl->egl_ctx);
@@ -533,3 +547,12 @@ bool virgl_egl_client_wait_fence(struct virgl_egl *egl, EGLSyncKHR fence, uint64
    }
    return ret != EGL_TIMEOUT_EXPIRED_KHR;
 }
+
+bool virgl_egl_export_signaled_fence(struct virgl_egl *egl, int *out_fd) {
+   return virgl_egl_export_fence(egl, egl->signaled_fence, out_fd);
+}
+
+bool virgl_egl_export_fence(struct virgl_egl *egl, EGLSyncKHR fence, int *out_fd) {
+   *out_fd = eglDupNativeFenceFDANDROID(egl->egl_display, fence);
+   return *out_fd != EGL_NO_NATIVE_FENCE_FD_ANDROID;
+}

src/vrend_winsys_egl.h

@@ -64,4 +64,6 @@ bool virgl_egl_supports_fences(struct virgl_egl *egl);
 EGLSyncKHR virgl_egl_fence_create(struct virgl_egl *egl);
 void virgl_egl_fence_destroy(struct virgl_egl *egl, EGLSyncKHR fence);
 bool virgl_egl_client_wait_fence(struct virgl_egl *egl, EGLSyncKHR fence, uint64_t timeout);
+bool virgl_egl_export_signaled_fence(struct virgl_egl *egl, int *out_fd);
+bool virgl_egl_export_fence(struct virgl_egl *egl, EGLSyncKHR fence, int *out_fd);
 #endif