[PATCH v5 3/4] rust/drm/gem: Add DriverAllocImpl type alias

[Lyude Paul <lyude@redhat.com>]

This is just a type alias that resolves into the AllocImpl for a given
  T: drm::gem::DriverObject

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
---
 rust/kernel/drm/gem/mod.rs | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/rust/kernel/drm/gem/mod.rs b/rust/kernel/drm/gem/mod.rs
index b4199945db378..ad74c5159f725 100644
--- a/rust/kernel/drm/gem/mod.rs
+++ b/rust/kernel/drm/gem/mod.rs
@@ -33,6 +33,11 @@
 /// [`DriverFile`]: drm::file::DriverFile
 pub type DriverFile<T> = drm::File<<<T as DriverObject>::Driver as drm::Driver>::File>;
 
+/// A type alias for retrieving the current [`AllocImpl`] for a given [`DriverObject`].
+///
+/// [`Driver`]: drm::Driver
+pub type DriverAllocImpl<T> = <<T as DriverObject>::Driver as drm::Driver>::Object;
+
 /// GEM object functions, which must be implemented by drivers.
 pub trait DriverObject: Sync + Send + Sized {
     /// Parent `Driver` for this object.
@@ -42,12 +47,12 @@ pub trait DriverObject: Sync + Send + Sized {
     fn new(dev: &drm::Device<Self::Driver>, size: usize) -> impl PinInit<Self, Error>;
 
     /// Open a new handle to an existing object, associated with a File.
-    fn open(_obj: &<Self::Driver as drm::Driver>::Object, _file: &DriverFile<Self>) -> Result {
+    fn open(_obj: &DriverAllocImpl<Self>, _file: &DriverFile<Self>) -> Result {
         Ok(())
     }
 
     /// Close a handle to an existing object, associated with a File.
-    fn close(_obj: &<Self::Driver as drm::Driver>::Object, _file: &DriverFile<Self>) {}
+    fn close(_obj: &DriverAllocImpl<Self>, _file: &DriverFile<Self>) {}
 }
 
 /// Trait that represents a GEM object subtype
-- 
2.53.0