From patchwork Fri Mar 21 21:47:53 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Danilo Krummrich X-Patchwork-Id: 14026072 X-Patchwork-Delegate: bhelgaas@google.com Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 212DE233725; Fri, 21 Mar 2025 21:48:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742593717; cv=none; b=uq7AdFjr0eWxSq2TK9dgxmx5uRXWwHCVFbgdR51mkQlQvxLaAWaflX5PDfzKtyCJ6woG1EnrsDEOaIN0to0UAmg2n7Sx+HTI8Hq6gZWxCr/xfgop2CqDzSVSytfuyTjh+mnmTAbfiuxOVhQ+O4eHCQH3ii47DrxhjsoP4lPrsIo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742593717; c=relaxed/simple; bh=MKwm/fHil0GDCiiaBpnQB8YlsfUYdX6rYlCKMcY4+DY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EA3UUjlTCSkkBISbnpVQjfTKEO5RVTvrvQRyCvfwBWzuqYIGvKvCQ1fJvK30VEGGjX/cjQKhQWQLmR/5u7tGCIlXA+nkHxWsmiGgtTotRRb7fV29fahx4kDvnQnzgRzshYj+eT/4ULBLYtDfEYbnSZAljaXdC8DRee6kuUhFR4E= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ErGzGUeW; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ErGzGUeW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 68E7EC4CEEA; Fri, 21 Mar 2025 21:48:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1742593716; bh=MKwm/fHil0GDCiiaBpnQB8YlsfUYdX6rYlCKMcY4+DY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ErGzGUeWHbq+jsK4mK0XixzZvRI8yW42+Q7dZbFSRUa6/P11+KQNUAQuYEjf1QoaJ PuQVkND+QgmP0jUk4K+lKzjLZ5eqvHwpJE0Si77vKqr2yaPL844mma6AGcXAV1sL2f G8OGC9AiGQReDTO10zROrYzjlBFfnCZrTVakzCrRX+rbId6c9t55TRqqGkkD9qlOax JQE0SvrPctCwIsVQ8ralYer+ZPBpe0YoQATM/HLx30Rrx5QZv1+bs8iXxP6ttbDDby ieFe2tI1XTNYgnRY4Sqak28E3XR2CwS86UsmVTf8edXStpNXAq2gyidX/TO0ANRitE axiu3jYaMMERQ== From: Danilo Krummrich To: bhelgaas@google.com, gregkh@linuxfoundation.org, rafael@kernel.org, ojeda@kernel.org, alex.gaynor@gmail.com, boqun.feng@gmail.com, gary@garyguo.net, bjorn3_gh@protonmail.com, benno.lossin@proton.me, a.hindborg@kernel.org, aliceryhl@google.com, tmgross@umich.edu Cc: linux-pci@vger.kernel.org, rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, Danilo Krummrich Subject: [PATCH v4 1/3] rust: device: implement bus_type_raw() Date: Fri, 21 Mar 2025 22:47:53 +0100 Message-ID: <20250321214826.140946-2-dakr@kernel.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250321214826.140946-1-dakr@kernel.org> References: <20250321214826.140946-1-dakr@kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Implement bus_type_raw(), which returns a raw pointer to the device' struct bus_type. This is useful for bus devices, to implement the following trait. impl TryFrom<&Device> for &pci::Device With this a caller can try to get the bus specific device from a generic device in a safe way. try_from() will only succeed if the generic device' bus type pointer matches the pointer of the bus' type. Reviewed-by: Alice Ryhl Reviewed-by: Benno Lossin Signed-off-by: Danilo Krummrich Reviewed-by: Greg Kroah-Hartman --- rust/kernel/device.rs | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/rust/kernel/device.rs b/rust/kernel/device.rs index 21b343a1dc4d..67a2fc46cf4c 100644 --- a/rust/kernel/device.rs +++ b/rust/kernel/device.rs @@ -65,6 +65,16 @@ pub(crate) fn as_raw(&self) -> *mut bindings::device { self.0.get() } + /// Returns a raw pointer to the device' bus type. + #[expect(unused)] + pub(crate) fn bus_type_raw(&self) -> *const bindings::bus_type { + // SAFETY: + // - By the type invariants, `self.as_raw()` is a valid pointer to a `struct device`. + // - `dev->bus` is a pointer to a `const struct bus_type`, which is only ever set at device + // creation. + unsafe { (*self.as_raw()).bus } + } + /// Convert a raw C `struct device` pointer to a `&'a Device`. /// /// # Safety