From nobody Tue Dec 16 09:29:37 2025 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 6B51A1E0DB3; Fri, 13 Dec 2024 13:47:46 +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=1734097666; cv=none; b=dJkEJDpfW4H5XCAzm8g+iA3L3J/JSVCCY97/bLmohFHSYuMNomuVtzc08542768tekcpLaksc9qsg/mCXFR1/iGVwZWuvd6b6jInBXl7D2dE41ueEBvW4O2L+JqZKA/LdKYY557IMhEWLOgsQ/+a+3w3GweUvyYMgUWdgdP7s4I= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734097666; c=relaxed/simple; bh=FUDuPCGiIzTe7+Z+u/MBEryhDck/6gCbdCtn7XdUV+o=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=kFrJJ2VVoR0w9ND4Yc0r5kmfI5pJ1oqzK4mhU6nOaTQ+cFOLm23swT7fN5MzohHHzTt0kLNqo7XVnKd28d8+MUYL4EFsmOkKUKZz6Y2rPDfA1tF9mKM9lBFlWfMvcpg8PbfUQUeXsaq8gMNZItVg7sKO6ir8jEoEUD9HI1K8V/A= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=t5KUZx7b; 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="t5KUZx7b" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3B5B8C4CED0; Fri, 13 Dec 2024 13:47:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1734097666; bh=FUDuPCGiIzTe7+Z+u/MBEryhDck/6gCbdCtn7XdUV+o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=t5KUZx7bDD+J0+axWwiOWGixA4kgDsoo0+oFdn/KH0Zy5OW6f8PAZzGPpOgbMvWKf r39Tb/4/P3VcEvgYXNYuE/61FLHN5MyMjmlZxRehlWvUSARi5lWMgB8NkbUPeDTjDA 3S4O6EfkbFBYiNcejxs0uXVOpy81u2fWpP07JPiwEv43kr/u29T9kG8WwVhGjsX2qy WFDYAPSjT1ouHA24ALekobuyxtWpabW2TiSqt8CYXYAmFfh076w/1nkQan46yuS04o BNi8ydaOIWK5P6+fAV/0kin1XrmgbHJWs+RrUMZwjGa2E5htFHx4gfNUnXQfzD7/NP uD/GWJnpnXt6Q== From: Lee Jones To: lee@kernel.org Cc: linux-kernel@vger.kernel.org, arnd@arndb.de, gregkh@linuxfoundation.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, rust-for-linux@vger.kernel.org Subject: [PATCH v6 2/5] samples: rust: Provide example using the new Rust MiscDevice abstraction Date: Fri, 13 Dec 2024 13:47:07 +0000 Message-ID: <20241213134715.601415-3-lee@kernel.org> X-Mailer: git-send-email 2.47.1.613.gc27f4b7a9f-goog In-Reply-To: <20241213134715.601415-1-lee@kernel.org> References: <20241213134715.601415-1-lee@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" This sample driver demonstrates the following basic operations: * Register a Misc Device * Create /dev/rust-misc-device * Provide open call-back for the aforementioned character device * Operate on the character device via a simple ioctl() * Provide close call-back for the character device Signed-off-by: Lee Jones Reviewed-by: Danilo Krummrich --- samples/rust/Kconfig | 10 ++++ samples/rust/Makefile | 1 + samples/rust/rust_misc_device.rs | 87 ++++++++++++++++++++++++++++++++ 3 files changed, 98 insertions(+) create mode 100644 samples/rust/rust_misc_device.rs diff --git a/samples/rust/Kconfig b/samples/rust/Kconfig index b0f74a81c8f9..df384e679901 100644 --- a/samples/rust/Kconfig +++ b/samples/rust/Kconfig @@ -20,6 +20,16 @@ config SAMPLE_RUST_MINIMAL =20 If unsure, say N. =20 +config SAMPLE_RUST_MISC_DEVICE + tristate "Misc device" + help + This option builds the Rust misc device. + + To compile this as a module, choose M here: + the module will be called rust_misc_device. + + If unsure, say N. + config SAMPLE_RUST_PRINT tristate "Printing macros" help diff --git a/samples/rust/Makefile b/samples/rust/Makefile index c1a5c1655395..ad4b97a98580 100644 --- a/samples/rust/Makefile +++ b/samples/rust/Makefile @@ -2,6 +2,7 @@ ccflags-y +=3D -I$(src) # needed for trace events =20 obj-$(CONFIG_SAMPLE_RUST_MINIMAL) +=3D rust_minimal.o +obj-$(CONFIG_SAMPLE_RUST_MISC_DEVICE) +=3D rust_misc_device.o obj-$(CONFIG_SAMPLE_RUST_PRINT) +=3D rust_print.o =20 rust_print-y :=3D rust_print_main.o rust_print_events.o diff --git a/samples/rust/rust_misc_device.rs b/samples/rust/rust_misc_devi= ce.rs new file mode 100644 index 000000000000..324c3696ae3f --- /dev/null +++ b/samples/rust/rust_misc_device.rs @@ -0,0 +1,87 @@ +// SPDX-License-Identifier: GPL-2.0 + +// Copyright (C) 2024 Google LLC. + +//! Rust misc device sample. + +use kernel::{ + c_str, + device::Device, + fs::File, + ioctl::_IO, + miscdevice::{MiscDevice, MiscDeviceOptions, MiscDeviceRegistration}, + prelude::*, + types::ARef, +}; + +const RUST_MISC_DEV_HELLO: u32 =3D _IO('|' as u32, 0x80); + +module! { + type: RustMiscDeviceModule, + name: "rust_misc_device", + author: "Lee Jones", + description: "Rust misc device sample", + license: "GPL", +} + +#[pin_data] +struct RustMiscDeviceModule { + #[pin] + _miscdev: MiscDeviceRegistration, +} + +impl kernel::InPlaceModule for RustMiscDeviceModule { + fn init(_module: &'static ThisModule) -> impl PinInit { + pr_info!("Initialising Rust Misc Device Sample\n"); + + let options =3D MiscDeviceOptions { + name: c_str!("rust-misc-device"), + }; + + try_pin_init!(Self { + _miscdev <- MiscDeviceRegistration::register(options), + }) + } +} + +struct RustMiscDevice { + dev: ARef, +} + +#[vtable] +impl MiscDevice for RustMiscDevice { + type Ptr =3D KBox; + + fn open(_file: &File, misc: &MiscDeviceRegistration) -> Result> { + let dev =3D ARef::from(misc.device()); + + dev_info!(dev, "Opening Rust Misc Device Sample\n"); + + Ok(KBox::new(RustMiscDevice { dev }, GFP_KERNEL)?) + } + + fn ioctl( + me: ::Borrowed<'_>, + _file: &File, + cmd: u32, + _arg: usize, + ) -> Result { + dev_info!(me.dev, "IOCTLing Rust Misc Device Sample\n"); + + match cmd { + RUST_MISC_DEV_HELLO =3D> dev_info!(me.dev, "Hello from the Rus= t Misc Device\n"), + _ =3D> { + dev_err!(me.dev, "-> IOCTL not recognised: {}\n", cmd); + return Err(ENOTTY); + } + } + + Ok(0) + } +} + +impl Drop for RustMiscDevice { + fn drop(&mut self) { + dev_info!(self.dev, "Exiting the Rust Misc Device Sample\n"); + } +} --=20 2.47.1.613.gc27f4b7a9f-goog