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AJvYcCVSl7KFQBDqNJaP0w4+UBuZBt6renr1nGoYMulwGVvVPsNMoSKr1IhQfBhLXXW7MprfMgGA7AQ3eu/K6y/ymg==@vger.kernel.org X-Gm-Message-State: AOJu0Yzjw6odjvdg0pL+6RkViFqd/Ix07hzUl0fZatHrrqSCskWh/fpW gGOeTcIPnpf2w2X0T/gtP94qVViRuMoKWPBqd2Ppj812yq+e++8Fclu+lakk27O1Y+iz7HiJSuY uNaRyhPxF3i9rmHy0rQ== X-Google-Smtp-Source: AGHT+IFKkROM8S2X6hVulNORyOvZuDhzod4S25WBIXPkUp5czDXn3G5vouDaPDJnP39FfaquJRTrfKsYSOa93Dc= X-Received: from wmbdq8.prod.google.com ([2002:a05:600c:64c8:b0:43d:847a:8ccc]) (user=aliceryhl job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:1e1c:b0:43d:9d5:474d with SMTP id 5b1f17b1804b1-442fef3e822mr143806575e9.0.1747677997829; Mon, 19 May 2025 11:06:37 -0700 (PDT) Date: Mon, 19 May 2025 18:06:35 +0000 In-Reply-To: <20250517-b4-rust_miscdevice_registrationdata-v3-0-cdb33e228d37@gmail.com> Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250517-b4-rust_miscdevice_registrationdata-v3-0-cdb33e228d37@gmail.com> Message-ID: Subject: Re: [PATCH v3 0/2] rust: miscdevice: add additional data to MiscDeviceRegistration From: Alice Ryhl To: Christian Schrefl Cc: Miguel Ojeda , Alex Gaynor , Boqun Feng , Gary Guo , "=?utf-8?B?QmrDtnJu?= Roy Baron" , Benno Lossin , Andreas Hindborg , Trevor Gross , Arnd Bergmann , Greg Kroah-Hartman , Lee Jones , Daniel Almeida , Danilo Krummrich , "Gerald =?utf-8?Q?Wisb=C3=B6ck?=" , rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" On Sat, May 17, 2025 at 01:33:48PM +0200, Christian Schrefl wrote: > Currently there is no good way to pass arbitrary data from the driver to > a `miscdevice` or to share data between individual handles to a > `miscdevice` in rust. > > This series adds additional (generic) data to the MiscDeviceRegistration > for this purpose. > > The first patch implements the changes and fixes the build of the sample > without changing any functionality (this is currently the only in tree > user). > > The second patch changes the `rust_misc_device` sample to use this to > share the same data between multiple handles to the `miscdevice`. > I have tested the sample with qemu and the C userspace example > from the doc comments. > > This series its based on my `UnsafePinned` series [0] and the > pin-init-next branch. > > Some discussion on Zulip about the motivation and approach [1]. > Thanks a lot to everyone helping me out with this. > > Link: https://lore.kernel.org/rust-for-linux/20250430-rust_unsafe_pinned-v2-0-fc8617a74024@gmail.com/ [0] > Link: https://rust-for-linux.zulipchat.com/#narrow/channel/288089-General/topic/Passing.20a.20DevRes.20to.20a.20miscdev/near/494553814 [1] > > Signed-off-by: Christian Schrefl Reviewed-by: Alice Ryhl Danilo's comment on the design of miscdevice is fair - it does not match other types of drivers. But this series is an improvement over what is here today. Alice