gallium: add external usage flags to resource_from(get)_handle (v2)

This will allow drivers to make better decisions about texture sharing
for DRI2, DRI3, Wayland, and OpenCL.

v2: add read/write flags, take advantage of __DRI_IMAGE_USE_BACKBUFFER

Reviewed-by: Axel Davy <[email protected]>

2 files changed, 19 insertions, 2 deletions

diff --git a/src/gallium/include/pipe/p_defines.h b/src/gallium/include/pipe/p_defines.h
index a91e6e55055..c9149bea309 100644
--- a/src/gallium/include/pipe/p_defines.h
+++ b/src/gallium/include/pipe/p_defines.h
@@ -530,6 +530,17 @@ enum pipe_reset_status
 
 
 /**
+ * resource_get_handle flags.
+ */
+/* Requires pipe_context::flush_resource before external use. */
+#define PIPE_HANDLE_USAGE_EXPLICIT_FLUSH  (1 << 0)
+/* Expected external use of the resource: */
+#define PIPE_HANDLE_USAGE_READ            (1 << 1)
+#define PIPE_HANDLE_USAGE_WRITE           (1 << 2)
+#define PIPE_HANDLE_USAGE_READ_WRITE      (PIPE_HANDLE_USAGE_READ | \
+                                           PIPE_HANDLE_USAGE_WRITE)
+
+/**
  * Implementation capabilities/limits which are queried through
  * pipe_screen::get_param()
  */
diff --git a/src/gallium/include/pipe/p_screen.h b/src/gallium/include/pipe/p_screen.h
index 211bc2440f9..4f30e75ab49 100644
--- a/src/gallium/include/pipe/p_screen.h
+++ b/src/gallium/include/pipe/p_screen.h
@@ -182,10 +182,13 @@ struct pipe_screen {
     * NOTE: in the case of DRM_API_HANDLE_TYPE_FD handles, the caller
     * retains ownership of the FD.  (This is consistent with
     * EGL_EXT_image_dma_buf_import)
+    *
+    * \param usage  A combination of PIPE_HANDLE_USAGE_* flags.
     */
    struct pipe_resource * (*resource_from_handle)(struct pipe_screen *,
 						  const struct pipe_resource *templat,
-						  struct winsys_handle *handle);
+						  struct winsys_handle *handle,
+						  unsigned usage);
 
    /**
     * Create a resource from user memory. This maps the user memory into
@@ -203,10 +206,13 @@ struct pipe_screen {
     * NOTE: in the case of DRM_API_HANDLE_TYPE_FD handles, the caller
     * takes ownership of the FD.  (This is consistent with
     * EGL_MESA_image_dma_buf_export)
+    *
+    * \param usage  A combination of PIPE_HANDLE_USAGE_* flags.
     */
    boolean (*resource_get_handle)(struct pipe_screen *,
 				  struct pipe_resource *tex,
-				  struct winsys_handle *handle);
+				  struct winsys_handle *handle,
+				  unsigned usage);
 
 
    void (*resource_destroy)(struct pipe_screen *,