From nobody Tue Oct 7 16:28:29 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 E98902405E8; Tue, 8 Jul 2025 19:46:21 +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=1752003982; cv=none; b=JKO3qILIjWV5XM9lsxmswuO/gabG8vl0+5/HJRY891kMCur66dqiybf6N9x0n9IwNGnvw6xQ36yB2UwlTjrU6dIzg+f7y4A7I99XupYZ8vW8EX6Gn9mnuIQg9rdm2emGo0Anu+Dy4jjYU5If6GBx/GrT5wKLY3XVBegbknJu3tE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752003982; c=relaxed/simple; bh=rI3PMBuRoxQk4V0KGavukqegyFDWNHFNecQhnnrOVMI=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=q4eq3EF0Pln2zWlusckkSxsujR6dDGQAx+mKvttVSYvwkyY+J9KmNAAXfyHUiFy4Ef1p4LAg94NXWv4np8/Y9w1QK/q5TwWoROPQ67u33LCnlmXJXCycf1uWqUBYU7PA9rFNkHF4QxZEjt5cnUAd/6EwhzbJunuMEDpZjRKiigk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=PFiH8R4n; 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="PFiH8R4n" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 94773C4CEED; Tue, 8 Jul 2025 19:46:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752003981; bh=rI3PMBuRoxQk4V0KGavukqegyFDWNHFNecQhnnrOVMI=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=PFiH8R4nnhGB68C/FqbYxA5++Esk9oIVZpkEpqIdFEMYMgw4nyFCheJmXXaKk1ILM Hpe4rLts9To3oH8Gd0TK8H4oqg4WZ3mNtSEzJvcpGrsetsRZHSe+kollITl5nWMINF bUaUDtApZlfP0CjWRf4PRGBa5Z1s12ljtasFUoK40u9dGwZpkYe6LS22PKK1kWGr9n 42DOF24rX5KngonVpvwBaWkUtdHCl9hLbbTqYuL6SWE0FVKQiWznGgjeYP4ricsHDg m0ykS1/SFl2uvs4NC2zxKFymJLheIf0W2oK+rK5e/SewcpXC+5hn1Fnxx2I7FhINzM 5LozSIsssxHEg== From: Andreas Hindborg Date: Tue, 08 Jul 2025 21:45:00 +0200 Subject: [PATCH v2 05/14] rust: block: use `NullBorrowFormatter` Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20250708-rnull-up-v6-16-v2-5-ab93c0ff429b@kernel.org> References: <20250708-rnull-up-v6-16-v2-0-ab93c0ff429b@kernel.org> In-Reply-To: <20250708-rnull-up-v6-16-v2-0-ab93c0ff429b@kernel.org> To: Boqun Feng , Miguel Ojeda , Alex Gaynor , Gary Guo , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , Benno Lossin , Alice Ryhl , Trevor Gross , Danilo Krummrich , Jens Axboe Cc: linux-block@vger.kernel.org, rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, Andreas Hindborg X-Mailer: b4 0.15-dev X-Developer-Signature: v=1; a=openpgp-sha256; l=3200; i=a.hindborg@kernel.org; h=from:subject:message-id; bh=rI3PMBuRoxQk4V0KGavukqegyFDWNHFNecQhnnrOVMI=; b=owEBbQKS/ZANAwAIAeG4Gj55KGN3AcsmYgBobXVEwXx/A97m/Qc65sLZ0qY5/J1wRThTKRGFo kVCyU9sm5KJAjMEAAEIAB0WIQQSwflHVr98KhXWwBLhuBo+eShjdwUCaG11RAAKCRDhuBo+eShj dxvQEAC+gnO0EHTbKeHnj9f2L9pEzdhwkcR5/OUeySZcSzi3O+xyQzUBte0OUCZqqT+GZI8bUxN 16klAl9nvGweu4J1pK9lSOnB88ArwbsU6VlyBFXTu4MIhiVrNzrRXHcgSk1hmyIiXxiONR6pYh+ +2Xpw/m3i31EngidyC0+Bq+4DvPh0KZQpJgn2qZqRXlHZ7LnTHKrZpqbLuOBfuJ2dia/Oo1d7A/ 9+18ugpOko+IpX0p1nRQWHtIs34IX0vIugMzV51SzbHZmelh5WFxUbeUcY5yaXbPtV46o2BpDos G1Iv9UoebD4N9QiuEoQKfXlrRxNFiWzrGw10OAKKXAdbnU4NpIin33kxeTGh9KFsu9bEVDppoW1 +abDoW7e0Rqzoa5XSZNYC4hx5wPTylC7jiqC+zEL8Gjj6+fOK5/J57L5efzsgWNiBr72jzYcz/b +YByiC9uR281XeEOJrPLPwjBt2B52/7oG6UQn2Hdh1RCFjFfQ/Omyn51obUyT4aKCDZI8hrEQVZ ieS7iX6Eq93nwN05LBkC5QcDPqH/wfU8ePVIYN2yEetZn8D2GaY7jkCCw90SL0DsmIYMk1ihynD GeFIYV1+zFpH3nmH/kRUEnwSX7MX7QbsU3UF+L3lbTxfnRDsB6sQZpDb0qiW478BYDsto6zKsYf Up7ROsVQTYG80Fg== X-Developer-Key: i=a.hindborg@kernel.org; a=openpgp; fpr=3108C10F46872E248D1FB221376EB100563EF7A7 Use the new `NullBorrowFormatter` to write the name of a `GenDisk` to the name buffer. This new formatter automatically adds a trailing null marker after the written characters, so we don't need to append that at the call site any longer. Signed-off-by: Andreas Hindborg --- rust/kernel/block/mq/gen_disk.rs | 8 ++++---- rust/kernel/block/mq/raw_writer.rs | 1 + rust/kernel/str.rs | 7 ------- 3 files changed, 5 insertions(+), 11 deletions(-) diff --git a/rust/kernel/block/mq/gen_disk.rs b/rust/kernel/block/mq/gen_di= sk.rs index 679ee1bb21950..e0e42f7028276 100644 --- a/rust/kernel/block/mq/gen_disk.rs +++ b/rust/kernel/block/mq/gen_disk.rs @@ -7,9 +7,10 @@ =20 use crate::{ bindings, - block::mq::{raw_writer::RawWriter, Operations, TagSet}, + block::mq::{Operations, TagSet}, error::{self, from_err_ptr, Result}, static_lock_class, + str::NullBorrowFormatter, sync::Arc, }; use core::fmt::{self, Write}; @@ -143,14 +144,13 @@ pub fn build( // SAFETY: `gendisk` is a valid pointer as we initialized it above unsafe { (*gendisk).fops =3D &TABLE }; =20 - let mut raw_writer =3D RawWriter::from_array( + let mut writer =3D NullBorrowFormatter::from_array( // SAFETY: `gendisk` points to a valid and initialized instanc= e. We // have exclusive access, since the disk is not added to the V= FS // yet. unsafe { &mut (*gendisk).disk_name }, )?; - raw_writer.write_fmt(name)?; - raw_writer.write_char('\0')?; + writer.write_fmt(name)?; =20 // SAFETY: `gendisk` points to a valid and initialized instance of // `struct gendisk`. `set_capacity` takes a lock to synchronize th= is diff --git a/rust/kernel/block/mq/raw_writer.rs b/rust/kernel/block/mq/raw_= writer.rs index 7e2159e4f6a6f..0aef55703e71d 100644 --- a/rust/kernel/block/mq/raw_writer.rs +++ b/rust/kernel/block/mq/raw_writer.rs @@ -24,6 +24,7 @@ fn new(buffer: &'a mut [u8]) -> Result> { Ok(Self { buffer, pos: 0 }) } =20 + #[expect(dead_code)] pub(crate) fn from_array( a: &'a mut [crate::ffi::c_char; N], ) -> Result> { diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs index 05d79cf40c201..4140b4af64e50 100644 --- a/rust/kernel/str.rs +++ b/rust/kernel/str.rs @@ -881,7 +881,6 @@ pub(crate) fn new(buffer: &'a mut [u8]) -> Result> { Ok(Self { buffer, pos: 0 }) } =20 - #[expect(dead_code)] pub(crate) fn from_array( a: &'a mut [crate::ffi::c_char; N], ) -> Result> { @@ -891,12 +890,6 @@ pub(crate) fn from_array( unsafe { core::slice::from_raw_parts_mut(a.as_mut_ptr().cast::= (), N) }, ) } - - /// Return the position of the write pointer in the underlying buffer. - #[expect(dead_code)] - pub(crate) fn pos(&self) -> usize { - self.pos - } } =20 impl Write for NullBorrowFormatter<'_> { --=20 2.47.2