From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sender4-pp-f112.zoho.com (sender4-pp-f112.zoho.com [136.143.188.112]) (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 B8989302760; Wed, 27 Aug 2025 13:51:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.112 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756302693; cv=pass; b=Q3XjQP3MSe+6GScPmsT/omrpMz1lLFk9S9MLBe9zbd5/bDYZA4yzzhWUqh9F/cGHXblX3WeP/ObNp1s8UHfoGP7L/6TDAetyYeLbVGKYnMuW7R1fdo+JBZURe/GrxxTQKg8mxDtDKDkxQG4bioyoDowfK9uop7HUs16WZzCQitU= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756302693; c=relaxed/simple; bh=dpx+34T0+fZYkD6nLJf/61+zs/Qi67xKeRs8hN0+VPA=; h=Content-Type:Mime-Version:Subject:From:In-Reply-To:Date:Cc: Message-Id:References:To; b=JWnbPAD8zkZSgZGg/DAtzd1wfkoBOuA+zzEpsTnT1tVGokiJD4ChJ4rLuar6xXeIsywXGwymZejBt820IANrpfxMRNpyyvmPUxaArSjLFfnNH3LYtAmPybWhA4c9Cd9p1Rpm48UsIvWj0GpV+/8XWJAez2u0/2LBezVqqUzLFhc= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (1024-bit key) header.d=collabora.com header.i=daniel.almeida@collabora.com header.b=AHMcxDmJ; arc=pass smtp.client-ip=136.143.188.112 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=collabora.com header.i=daniel.almeida@collabora.com header.b="AHMcxDmJ" ARC-Seal: i=1; a=rsa-sha256; t=1756302673; cv=none; d=zohomail.com; s=zohoarc; b=QAXGvRVHHe5QDnlNjnzorWJGhYtShm8DkXSQyeZgi8VlCUcwDkaDrvFiT2dCkka1oB2e+aDDn5HxVww+8ZUKvpbx9gTRwm8sgkq6Jl1gaQGDLG8viXWjtvJFsX78hlyob2pz2gCaFAbvUx/yoqnpaAKymW12kt3w2WWJOUjFmhM= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1756302673; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=r87d2Cvfv+EDJTx1X2oLOP11FqHTagC0pyB7B8rLf/I=; b=iLu3geV1YZ3/ECNE7c+DXKxRNhDFLDQbVLia+SKyuj0iRVGbsb9FFkySXwvoI3pSkdIwZj2Y8UvvgPbWzLIERnKqOKDYnaxYKiBUK6wPCeX3P3ufViFmGQThy9t651/po85ohg5uhfY6pOJX+hxx50GenLHyvcgxYOk8XwkTRIw= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=daniel.almeida@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1756302673; s=zohomail; d=collabora.com; i=daniel.almeida@collabora.com; h=Content-Type:Mime-Version:Subject:Subject:From:From:In-Reply-To:Date:Date:Cc:Cc:Content-Transfer-Encoding:Message-Id:Message-Id:References:To:To:Reply-To; bh=r87d2Cvfv+EDJTx1X2oLOP11FqHTagC0pyB7B8rLf/I=; b=AHMcxDmJW1Adv9BXTlQqPTy/OYKFc8fCJJKsAPuzX3Pkk81BMHG4OXozbgCwf4VD +nrlXcgD/8yIOkQRLRDzwbUKvd/Spbur0/9fvZXTo06ApV9LrChf4dxGr5tzgF3c0SS wHv/TnbMq9ybNjLB0MFEO/fH7cdriLpA+lTFxuzw= Received: by mx.zohomail.com with SMTPS id 1756302671144595.2863081348415; Wed, 27 Aug 2025 06:51:11 -0700 (PDT) Content-Type: text/plain; charset=us-ascii Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3826.700.81\)) Subject: Re: [PATCH v6 09/18] rust: block: use `NullTerminatedFormatter` From: Daniel Almeida In-Reply-To: <20250822-rnull-up-v6-16-v6-9-ec65006e2f07@kernel.org> Date: Wed, 27 Aug 2025 10:50:55 -0300 Cc: 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 , Breno Leitao , linux-block@vger.kernel.org, rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Message-Id: <511180A3-DC0B-40B6-994E-AC8A7A7F6EF3@collabora.com> References: <20250822-rnull-up-v6-16-v6-0-ec65006e2f07@kernel.org> <20250822-rnull-up-v6-16-v6-9-ec65006e2f07@kernel.org> To: Andreas Hindborg X-Mailer: Apple Mail (2.3826.700.81) X-ZohoMailClient: External > On 22 Aug 2025, at 09:14, Andreas Hindborg = wrote: >=20 > Use the new `NullTerminatedFormatter` 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. >=20 > Reviewed-by: Alice Ryhl > Signed-off-by: Andreas Hindborg > --- > rust/kernel/block/mq/gen_disk.rs | 12 +++++++----- > rust/kernel/block/mq/raw_writer.rs | 1 + > rust/kernel/str.rs | 1 - > 3 files changed, 8 insertions(+), 6 deletions(-) >=20 > diff --git a/rust/kernel/block/mq/gen_disk.rs = b/rust/kernel/block/mq/gen_disk.rs > index 679ee1bb2195..20f1d46c774d 100644 > --- a/rust/kernel/block/mq/gen_disk.rs > +++ b/rust/kernel/block/mq/gen_disk.rs > @@ -7,9 +7,11 @@ >=20 > use crate::{ > bindings, > - block::mq::{raw_writer::RawWriter, Operations, TagSet}, > + block::mq::{Operations, TagSet}, > error::{self, from_err_ptr, Result}, > + prelude::*, > static_lock_class, > + str::NullTerminatedFormatter, > sync::Arc, > }; > use core::fmt::{self, Write}; > @@ -143,14 +145,14 @@ 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 NullTerminatedFormatter::new( > // SAFETY: `gendisk` points to a valid and initialized = instance. We > // have exclusive access, since the disk is not added to = the VFS > // yet. > unsafe { &mut (*gendisk).disk_name }, > - )?; > - raw_writer.write_fmt(name)?; > - raw_writer.write_char('\0')?; > + ) > + .ok_or(EINVAL)?; > + writer.write_fmt(name)?; >=20 > // SAFETY: `gendisk` points to a valid and initialized = instance of > // `struct gendisk`. `set_capacity` takes a lock to = synchronize this > diff --git a/rust/kernel/block/mq/raw_writer.rs = b/rust/kernel/block/mq/raw_writer.rs > index 7e2159e4f6a6..0aef55703e71 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 b185262b4851..a3e34f566034 100644 > --- a/rust/kernel/str.rs > +++ b/rust/kernel/str.rs > @@ -886,7 +886,6 @@ pub(crate) struct NullTerminatedFormatter<'a> { >=20 > impl<'a> NullTerminatedFormatter<'a> { > /// Create a new [`Self`] instance. > - #[expect(dead_code)] > pub(crate) fn new(buffer: &'a mut [u8]) -> = Option> { > *(buffer.first_mut()?) =3D 0; >=20 >=20 > --=20 > 2.47.2 >=20 >=20 >=20 Reviewed-by: Daniel Almeida =