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AJvYcCX35+/WmsDqoCw9dK+CqIZ/Sx4T6oWrDbW322wAY7aLA3tbbv0ZqvxGeAiEVtdmD5XcFpIAM3H6S8Ox+fFs3g==@vger.kernel.org X-Gm-Message-State: AOJu0Yzm+LwYyp3NCaf2DTX3DRgfdm0Jlu6fSceq/rKiPGMEQHWc9uql 6hSQdTpnSWS5O0ut55Ev8udYgdjghbP4VoFyEhfCHjLqZld2So1S3LOMdZGoVHne+3S527lZRun CKWvn9LMKyNyPyHNM3w== X-Google-Smtp-Source: AGHT+IGjjOW9Oot2bFj3PWG3PB/y8G0bJgwiY7qUCIY2PFZOfhA37fiaHW8yWyvMMhKKK1+HLzZXKQmndCci3yU= X-Received: from wmbgw8.prod.google.com ([2002:a05:600c:8508:b0:451:d768:b11d]) (user=aliceryhl job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:46d0:b0:456:28d4:ef1 with SMTP id 5b1f17b1804b1-45892bdff7bmr94283905e9.29.1754039597687; Fri, 01 Aug 2025 02:13:17 -0700 (PDT) Date: Fri, 1 Aug 2025 09:13:16 +0000 In-Reply-To: <20250731154919.4132-5-dakr@kernel.org> Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250731154919.4132-1-dakr@kernel.org> <20250731154919.4132-5-dakr@kernel.org> Message-ID: Subject: Re: [PATCH 4/4] rust: drm: don't pass the address of drm::Device to drm_dev_put() From: Alice Ryhl To: Danilo Krummrich Cc: lorenzo.stoakes@oracle.com, vbabka@suse.cz, Liam.Howlett@oracle.com, urezki@gmail.com, ojeda@kernel.org, alex.gaynor@gmail.com, boqun.feng@gmail.com, gary@garyguo.net, bjorn3_gh@protonmail.com, lossin@kernel.org, a.hindborg@kernel.org, tmgross@umich.edu, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, airlied@gmail.com, simona@ffwll.ch, rust-for-linux@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" On Thu, Jul 31, 2025 at 05:48:09PM +0200, Danilo Krummrich wrote: > In drm_dev_put() call in AlwaysRefCounted::dec_ref() we rely on struct > drm_device to be the first field in drm::Device, whereas everywhere > else we correctly obtain the address of the actual struct drm_device. > > Analogous to the from_drm_device() helper, provide the > into_drm_device() helper in order to address this. > > Fixes: 1e4b8896c0f3 ("rust: drm: add device abstraction") > Signed-off-by: Danilo Krummrich > + /// # Safety > + /// > + /// `ptr` must be a valid pointer to `Self`. > + unsafe fn into_drm_device(ptr: NonNull) -> *mut bindings::drm_device { > + // SAFETY: By the safety requirements of this function, `ptr` is a valid pointer to `Self`. > + unsafe { &raw mut (*ptr.as_ptr()).dev }.cast() > + } I think it would somewhat more consistent to use the naming raw_get() or cast_into(), but I am ok with this naming too. Reviewed-by: Alice Ryhl Alice