From nobody Thu Dec 18 01:38:46 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 66B2C2036F3; Fri, 6 Dec 2024 12:42:54 +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=1733488974; cv=none; b=MQ0z+OGpOgS1x0mHUiFG+Ni03+muOWS6+BGQ/qn0aNU+23fPubTeXtU7T/NmhUE4p7PNz9QUTe2z5loe99hRCFg67GPeKFBYJ1lpyHYXpLJ7aKzIbXCjBV2dha1T5HEXvEPKDdG1cGl3newf8r8TqkWB7N7uFQgpwylr+uMA0f0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733488974; c=relaxed/simple; bh=WFkpKiXyvQ59F/bCxcLhHbqQzdnF8Nx2WniZliuSybA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=r1HXOVb970uX0osP3/CB42yIR1d85vNdKbKED59R0c/b7dh+E46SKfviHwKVVZ/FrjKUgu3iqKn3BKI++/CVGtNrmnuuvaNwYR7Lg/K9sRYl37ACl7cANAADwOmFYIpIKaUW3QQT1VGRovUXwonB+pLXRcI+ilceiaQahl9hvAE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DE0a3bPG; 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="DE0a3bPG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1EA29C4CED1; Fri, 6 Dec 2024 12:42:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1733488974; bh=WFkpKiXyvQ59F/bCxcLhHbqQzdnF8Nx2WniZliuSybA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DE0a3bPGqAObx3iJSMPQZ6MAwgC8vB5Y6m7QdcN6s3rnH+xu64+/8Y0LzfBjSSDe5 1pUkXu+E4hmzoqWKgx11Vksm31z1+wii+CZHhxO0U6oq4Fc+lqRXVO9ufi6rJgEmJ2 SPG6nOMW/DesdRZ4nPCdjbIS+YixUdCCVZjo7qL0P+G379H+ny6FViMdxPGgHkCBn0 7ZBtyf3XNwFaTXcNUX/bnm5TW0ef2ZlB0AR2ItIBqdt6G1UcnsBf4L+vSGQONAWbIq OUgKI/l4AloKTGEem/1AbILRUv6XqhYfzNqJTdaow2fNX3wym6pdh7N/JoMqGuM2vt rlWY3pj/Wzbrg== 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 v5 2/4] samples: rust: Provide example using the new Rust MiscDevice abstraction Date: Fri, 6 Dec 2024 12:42:13 +0000 Message-ID: <20241206124218.165880-3-lee@kernel.org> X-Mailer: git-send-email 2.47.0.338.g60cca15819-goog In-Reply-To: <20241206124218.165880-1-lee@kernel.org> References: <20241206124218.165880-1-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 --- samples/rust/Kconfig | 10 ++++ samples/rust/Makefile | 1 + samples/rust/rust_misc_device.rs | 79 ++++++++++++++++++++++++++++++++ 3 files changed, 90 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..c94b56c454fb --- /dev/null +++ b/samples/rust/rust_misc_device.rs @@ -0,0 +1,79 @@ +// SPDX-License-Identifier: GPL-2.0 + +// Copyright (C) 2024 Google LLC. + +//! Rust misc device sample. + +use kernel::{ + c_str, + ioctl::_IO, + miscdevice::{MiscDevice, MiscDeviceOptions, MiscDeviceRegistration}, + prelude::*, +}; + +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; + +#[vtable] +impl MiscDevice for RustMiscDevice { + type Ptr =3D KBox; + + fn open() -> Result> { + pr_info!("Opening Rust Misc Device Sample\n"); + + Ok(KBox::new(RustMiscDevice, GFP_KERNEL)?) + } + + fn ioctl( + _device: ::Borrowed<'_= >, + cmd: u32, + _arg: usize, + ) -> Result { + pr_info!("IOCTLing Rust Misc Device Sample\n"); + + match cmd { + RUST_MISC_DEV_HELLO =3D> pr_info!("Hello from the Rust Misc De= vice\n"), + _ =3D> { + pr_err!("IOCTL not recognised: {}\n", cmd); + return Err(ENOTTY); + } + } + + Ok(0) + } +} + +impl Drop for RustMiscDevice { + fn drop(&mut self) { + pr_info!("Exiting the Rust Misc Device Sample\n"); + } +} --=20 2.47.0.338.g60cca15819-goog