1 files changed, 17 insertions, 9 deletions

diff --git a/rust/kernel/drm/device.rs b/rust/kernel/drm/device.rs
index 624d7a4c83ea..3bb7c83966cf 100644
--- a/rust/kernel/drm/device.rs
+++ b/rust/kernel/drm/device.rs
@@ -66,7 +66,7 @@ impl<T: drm::Driver> Device<T> {
         open: Some(drm::File::<T::File>::open_callback),
         postclose: Some(drm::File::<T::File>::postclose_callback),
         unload: None,
-        release: None,
+        release: Some(Self::release),
         master_set: None,
         master_drop: None,
         debugfs_init: None,
@@ -83,13 +83,13 @@ impl<T: drm::Driver> Device<T> {
         major: T::INFO.major,
         minor: T::INFO.minor,
         patchlevel: T::INFO.patchlevel,
-        name: T::INFO.name.as_char_ptr() as *mut _,
-        desc: T::INFO.desc.as_char_ptr() as *mut _,
+        name: T::INFO.name.as_char_ptr().cast_mut(),
+        desc: T::INFO.desc.as_char_ptr().cast_mut(),
 
         driver_features: drm::driver::FEAT_GEM,
         ioctls: T::IOCTLS.as_ptr(),
         num_ioctls: T::IOCTLS.len() as i32,
-        fops: &Self::GEM_FOPS as _,
+        fops: &Self::GEM_FOPS,
     };
 
     const GEM_FOPS: bindings::file_operations = drm::gem::create_fops();
@@ -135,11 +135,9 @@ impl<T: drm::Driver> Device<T> {
     ///
     /// `ptr` must be a valid pointer to a `struct device` embedded in `Self`.
     unsafe fn from_drm_device(ptr: *const bindings::drm_device) -> *mut Self {
-        let ptr: *const Opaque<bindings::drm_device> = ptr.cast();
-
         // SAFETY: By the safety requirements of this function `ptr` is a valid pointer to a
         // `struct drm_device` embedded in `Self`.
-        unsafe { crate::container_of!(ptr, Self, dev) }.cast_mut()
+        unsafe { crate::container_of!(Opaque::cast_from(ptr), Self, dev) }.cast_mut()
     }
 
     /// Not intended to be called externally, except via declare_drm_ioctls!()
@@ -154,7 +152,7 @@ impl<T: drm::Driver> Device<T> {
     /// Additionally, callers must ensure that the `struct device`, `ptr` is pointing to, is
     /// embedded in `Self`.
     #[doc(hidden)]
-    pub unsafe fn as_ref<'a>(ptr: *const bindings::drm_device) -> &'a Self {
+    pub unsafe fn from_raw<'a>(ptr: *const bindings::drm_device) -> &'a Self {
         // SAFETY: By the safety requirements of this function `ptr` is a valid pointer to a
         // `struct drm_device` embedded in `Self`.
         let ptr = unsafe { Self::from_drm_device(ptr) };
@@ -162,6 +160,16 @@ impl<T: drm::Driver> Device<T> {
         // SAFETY: `ptr` is valid by the safety requirements of this function.
         unsafe { &*ptr.cast() }
     }
+
+    extern "C" fn release(ptr: *mut bindings::drm_device) {
+        // SAFETY: `ptr` is a valid pointer to a `struct drm_device` and embedded in `Self`.
+        let this = unsafe { Self::from_drm_device(ptr) };
+
+        // SAFETY:
+        // - When `release` runs it is guaranteed that there is no further access to `this`.
+        // - `this` is valid for dropping.
+        unsafe { core::ptr::drop_in_place(this) };
+    }
 }
 
 impl<T: drm::Driver> Deref for Device<T> {
@@ -190,7 +198,7 @@ impl<T: drm::Driver> AsRef<device::Device> for Device<T> {
     fn as_ref(&self) -> &device::Device {
         // SAFETY: `bindings::drm_device::dev` is valid as long as the DRM device itself is valid,
         // which is guaranteed by the type invariant.
-        unsafe { device::Device::as_ref((*self.as_raw()).dev) }
+        unsafe { device::Device::from_raw((*self.as_raw()).dev) }
     }
 }