Patch "rust: device: change the from_raw() function" has been added to the 6.11-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    rust: device: change the from_raw() function

to the 6.11-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     rust-device-change-the-from_raw-function.patch
and it can be found in the queue-6.11 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit ab50b8c2fdf5688de2908bc767015e143b8c49a8
Author: Guilherme Giacomo Simoes <trintaeoitogc@xxxxxxxxx>
Date:   Tue Oct 1 17:56:03 2024 -0300

    rust: device: change the from_raw() function
    
    [ Upstream commit cc4332afb5631b0e9d2ce5699b7f4b7caf743526 ]
    
    The function Device::from_raw() increments a refcount by a call to
    bindings::get_device(ptr). This can be confused because usually
    from_raw() functions don't increment a refcount.
    Hence, rename Device::from_raw() to avoid confuion with other "from_raw"
    semantics.
    
    The new name of function should be "get_device" to be consistent with
    the function get_device() already exist in .c files.
    
    This function body also changed, because the `into()` will convert the
    `&'a Device` into `ARef<Device>` and also call `inc_ref` from the
    `AlwaysRefCounted` trait implemented for Device.
    
    Signed-off-by: Guilherme Giacomo Simoes <trintaeoitogc@xxxxxxxxx>
    Acked-by: Danilo Krummrich <dakr@xxxxxxxxxx>
    Closes: https://github.com/Rust-for-Linux/linux/issues/1088
    Reviewed-by: Boqun Feng <boqun.feng@xxxxxxxxx>
    Link: https://lore.kernel.org/r/20241001205603.106278-1-trintaeoitogc@xxxxxxxxx
    Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/rust/kernel/device.rs b/rust/kernel/device.rs
index 851018eef885e..c8199ee079eff 100644
--- a/rust/kernel/device.rs
+++ b/rust/kernel/device.rs
@@ -51,18 +51,9 @@ impl Device {
     ///
     /// It must also be ensured that `bindings::device::release` can be called from any thread.
     /// While not officially documented, this should be the case for any `struct device`.
-    pub unsafe fn from_raw(ptr: *mut bindings::device) -> ARef<Self> {
-        // SAFETY: By the safety requirements, ptr is valid.
-        // Initially increase the reference count by one to compensate for the final decrement once
-        // this newly created `ARef<Device>` instance is dropped.
-        unsafe { bindings::get_device(ptr) };
-
-        // CAST: `Self` is a `repr(transparent)` wrapper around `bindings::device`.
-        let ptr = ptr.cast::<Self>();
-
-        // SAFETY: `ptr` is valid by the safety requirements of this function. By the above call to
-        // `bindings::get_device` we also own a reference to the underlying `struct device`.
-        unsafe { ARef::from_raw(ptr::NonNull::new_unchecked(ptr)) }
+    pub unsafe fn get_device(ptr: *mut bindings::device) -> ARef<Self> {
+        // SAFETY: By the safety requirements ptr is valid
+        unsafe { Self::as_ref(ptr) }.into()
     }
 
     /// Obtain the raw `struct device *`.
diff --git a/rust/kernel/firmware.rs b/rust/kernel/firmware.rs
index dee5b4b18aec4..13a374a5cdb74 100644
--- a/rust/kernel/firmware.rs
+++ b/rust/kernel/firmware.rs
@@ -44,7 +44,7 @@ fn request_nowarn() -> Self {
 ///
 /// # fn no_run() -> Result<(), Error> {
 /// # // SAFETY: *NOT* safe, just for the example to get an `ARef<Device>` instance
-/// # let dev = unsafe { Device::from_raw(core::ptr::null_mut()) };
+/// # let dev = unsafe { Device::get_device(core::ptr::null_mut()) };
 ///
 /// let fw = Firmware::request(c_str!("path/to/firmware.bin"), &dev)?;
 /// let blob = fw.data();