gallium/u_upload_mgr: add a helper that creates the default uploader

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
Tested-by: Edmondo Tommasina <edmondo.tommasina@gmail.com>
Tested-by: Charmaine Lee <charmainel@vmware.com>

src/gallium/auxiliary/util/u_upload_mgr.c

@@ -86,6 +86,15 @@ u_upload_create(struct pipe_context *pipe, unsigned default_size,
    return upload;
 }
 
+struct u_upload_mgr *
+u_upload_create_default(struct pipe_context *pipe)
+{
+   return u_upload_create(pipe, 1024 * 1024,
+                          PIPE_BIND_VERTEX_BUFFER |
+                          PIPE_BIND_INDEX_BUFFER |
+                          PIPE_BIND_CONSTANT_BUFFER,
+                          PIPE_USAGE_STREAM);
+}
 
 static void upload_unmap_internal(struct u_upload_mgr *upload, boolean destroying)
 {

src/gallium/auxiliary/util/u_upload_mgr.h

@@ -51,6 +51,13 @@ struct u_upload_mgr *
 u_upload_create(struct pipe_context *pipe, unsigned default_size,
                 unsigned bind, enum pipe_resource_usage usage);
 
+/**
+ * Create the default uploader for pipe_context. Only pipe_context::screen
+ * needs to be set for this to succeed.
+ */
+struct u_upload_mgr *
+u_upload_create_default(struct pipe_context *pipe);
+
 /**
  * Destroy the upload manager.
  */