From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-40131.protonmail.ch (mail-40131.protonmail.ch [185.70.40.131]) (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 6073E27F4C4 for ; Tue, 4 Mar 2025 22:57:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.70.40.131 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741129021; cv=none; b=W/PAIGuuVaBP4uE4tmI/ltIfaCRwBEYrubV+/MVQGbY70j1H+XXex0jZ+T7/8siXHWY1/ftn0aKniKEWGzud+j1qqU8O2/4bGrnvejmPrK/19yVF9U+rzc47mY4jkpR06OEhj0nDCo9HSvRvTjFwE/GQ6C5oO9/XFIACpjMVjzM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741129021; c=relaxed/simple; bh=C6P89FCEKQ7hsnf3HcAy+ET8m/1mUKx+4UNKz3gB5dQ=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=odSwHBj7ftrcM64eNWYXRgHYwu21z+oQ91FteL9km4VsC4HNaYnwbv/n0QGccp5aIkFi1jJFtHFUwch2QuDpUxf/4AGyuaHMFbKKiI+Kxr4H27pQiP0boXnL1VzcGSvBIvPfGo4CIN34mLLYwGVM7YSmKjkg4bPHPwVHMkLfVro= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=proton.me; spf=pass smtp.mailfrom=proton.me; dkim=pass (2048-bit key) header.d=proton.me header.i=@proton.me header.b=UNT5dZyA; arc=none smtp.client-ip=185.70.40.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=proton.me Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=proton.me Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=proton.me header.i=@proton.me header.b="UNT5dZyA" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=proton.me; s=protonmail; t=1741129017; x=1741388217; bh=WCPISGW0WxDW396dH2Up0ucrRhbSpXK6XA4DV86Ew0k=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: Feedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID:BIMI-Selector:List-Unsubscribe:List-Unsubscribe-Post; b=UNT5dZyAYs3BZ7OxOTKMXQyRAiCl5tZ5xkWRfjzoNGja8F3Kolazy7+kH0wYBWwOB 8pcYdnjZJcOtAP4AfZhOfkuNgDXINvLjLQvnCOVjUuqpyJS05XnCLmRgl4sHyPRZ2W uvrdHf/DgkK8K1wU5bHQGksCEpfeB54ovjQ8BlJDjvbcTLPdQpwDJNa2GdQVhaH696 1UdkebQypo2tQLVZLzzCtx54ijc8hbp5rnR/YDW1N4kqfmhTowF0fAC3zVEydVrEon PuNrnon2f2w9pSJIJKvNjSiq02op8rFx5SK+biso0Ytzyyl7YpMJufPTWTAvdLNtAw meXp2ABBUrjdw== Date: Tue, 04 Mar 2025 22:56:51 +0000 To: Benno Lossin , Miguel Ojeda , Alex Gaynor , Boqun Feng , Gary Guo , =?utf-8?Q?Bj=C3=B6rn_Roy_Baron?= , Andreas Hindborg , Alice Ryhl , Trevor Gross , Danilo Krummrich From: Benno Lossin Cc: linux-kernel@vger.kernel.org, rust-for-linux@vger.kernel.org Subject: [RFC PATCH 1/6] rust: pin-init: internal: add syn version of the `Zeroable` derive macro Message-ID: <20250304225536.2033853-2-benno.lossin@proton.me> In-Reply-To: <20250304225536.2033853-1-benno.lossin@proton.me> References: <20250304225536.2033853-1-benno.lossin@proton.me> Feedback-ID: 71780778:user:proton X-Pm-Message-ID: a6eb2719ee7981c4beaecaa3f25a995a035ea555 Precedence: bulk X-Mailing-List: rust-for-linux@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 Implement the `Zeroable` derive macro using syn to simplify parsing by not going through an additional declarative macro. The syn version is only enabled in the user-space version and disabled in the kernel until syn becomes available there. Signed-off-by: Benno Lossin --- rust/pin-init/internal/src/lib.rs | 5 ++ rust/pin-init/internal/src/syn_zeroable.rs | 63 ++++++++++++++++++++++ 2 files changed, 68 insertions(+) create mode 100644 rust/pin-init/internal/src/syn_zeroable.rs diff --git a/rust/pin-init/internal/src/lib.rs b/rust/pin-init/internal/src= /lib.rs index babe5e878550..5019efe22662 100644 --- a/rust/pin-init/internal/src/lib.rs +++ b/rust/pin-init/internal/src/lib.rs @@ -30,6 +30,11 @@ mod helpers; mod pin_data; mod pinned_drop; +#[cfg(kernel)] +mod zeroable; + +#[cfg(not(kernel))] +#[path =3D "syn_zeroable.rs"] mod zeroable; =20 #[proc_macro_attribute] diff --git a/rust/pin-init/internal/src/syn_zeroable.rs b/rust/pin-init/int= ernal/src/syn_zeroable.rs new file mode 100644 index 000000000000..90ea8fa63c83 --- /dev/null +++ b/rust/pin-init/internal/src/syn_zeroable.rs @@ -0,0 +1,63 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + +use proc_macro2::TokenStream; +use quote::quote; +use syn::{ + parse_macro_input, parse_quote, Data, DataStruct, DeriveInput, Error, = GenericParam, Result, + TypeParam, WherePredicate, +}; + +pub(crate) fn derive(input: proc_macro::TokenStream) -> proc_macro::TokenS= tream { + let raw =3D input.clone().into(); + do_derive(parse_macro_input!(input as DeriveInput), raw) + .unwrap_or_else(|e| e.into_compile_error()) + .into() +} + +fn do_derive( + DeriveInput { + ident, + mut generics, + data, + .. + }: DeriveInput, + raw_input: TokenStream, +) -> Result { + let Data::Struct(DataStruct { fields, .. }) =3D data else { + return Err(Error::new_spanned( + raw_input, + "`Zeroable` can only be derived for structs.", + )); + }; + let field_ty =3D fields.iter().map(|f| &f.ty); + let zeroable_bounds =3D generics + .params + .iter() + .filter_map(|p| match p { + GenericParam::Type(TypeParam { ident, .. }) =3D> { + Some(parse_quote!(#ident: ::pin_init::Zeroable)) + } + _ =3D> None, + }) + .collect::>(); + generics + .make_where_clause() + .predicates + .extend(zeroable_bounds); + let (impl_generics, ty_generics, whr) =3D generics.split_for_impl(); + Ok(quote! { + // SAFETY: Every field type implements `Zeroable` and padding byte= s may be zero. + #[automatically_derived] + unsafe impl #impl_generics ::pin_init::Zeroable for #ident #ty_gen= erics + #whr + {} + const _: () =3D { + fn assert_zeroable() {} + fn ensure_zeroable #impl_generics () + #whr + { + #(assert_zeroable::<#field_ty>();)* + } + }; + }) +} --=20 2.48.1