[PATCH 01/11] rust: pin-init: internal: remove proc-macro[2] and quote workarounds

Gary Guo
2025-12-11T19:28:56Z

From: Benno Lossin <lossin@kernel.org>

The kernel only had the `proc-macro` library available, whereas the
user-space version also used `proc-macro2` and `quote`. Now both are
available to the kernel, making it possible to remove the workarounds.

Signed-off-by: Benno Lossin <lossin@kernel.org>
Co-developed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Gary Guo <gary@garyguo.net>
---
rust/Makefile | 8 +++++---
rust/pin-init/internal/src/helpers.rs | 5 +----
rust/pin-init/internal/src/lib.rs | 16 ----------------
rust/pin-init/internal/src/pin_data.rs | 6 ++----
rust/pin-init/internal/src/pinned_drop.rs | 6 ++----
rust/pin-init/internal/src/zeroable.rs | 6 ++----
scripts/generate_rust_analyzer.py | 2 +-
7 files changed, 13 insertions(+), 36 deletions(-)

diff --git a/rust/Makefile b/rust/Makefile
index 5d357dce1704d..c816ca8663e42 100644
--- a/rust/Makefile
+++ b/rust/Makefile
@@ -212,7 +212,8 @@ rustdoc-ffi: $(src)/ffi.rs rustdoc-core FORCE

rustdoc-pin_init_internal: private rustdoc_host = yes
rustdoc-pin_init_internal: private rustc_target_flags = --cfg kernel \
- --extern proc_macro --crate-type proc-macro
+ --extern proc_macro --extern proc_macro2 --extern quote --extern syn \
+ --crate-type proc-macro
rustdoc-pin_init_internal: $(src)/pin-init/internal/src/lib.rs \
rustdoc-clean FORCE
+$(call if_changed,rustdoc)
@@ -273,7 +274,7 @@ rusttestlib-macros: $(src)/macros/lib.rs \
+$(call if_changed,rustc_test_library)

rusttestlib-pin_init_internal: private rustc_target_flags = --cfg kernel \
- --extern proc_macro
+ --extern proc_macro --extern proc_macro2 --extern quote --extern syn
rusttestlib-pin_init_internal: private rustc_test_library_proc = yes
rusttestlib-pin_init_internal: $(src)/pin-init/internal/src/lib.rs FORCE
+$(call if_changed,rustc_test_library)
@@ -547,7 +548,8 @@ $(obj)/$(libmacros_name): $(src)/macros/lib.rs $(obj)/libproc_macro2.rlib \
$(obj)/libquote.rlib $(obj)/libsyn.rlib FORCE
+$(call if_changed_dep,rustc_procmacro)

-$(obj)/$(libpin_init_internal_name): private rustc_target_flags = --cfg kernel
+$(obj)/$(libpin_init_internal_name): private rustc_target_flags = --cfg kernel \
+ --extern proc_macro2 --extern quote --extern syn
$(obj)/$(libpin_init_internal_name): $(src)/pin-init/internal/src/lib.rs FORCE
+$(call if_changed_dep,rustc_procmacro)

diff --git a/rust/pin-init/internal/src/helpers.rs b/rust/pin-init/internal/src/helpers.rs
index 236f989a50f2f..1d2dd27c888c8 100644
--- a/rust/pin-init/internal/src/helpers.rs
+++ b/rust/pin-init/internal/src/helpers.rs
@@ -1,9 +1,6 @@
// SPDX-License-Identifier: Apache-2.0 OR MIT

-#[cfg(not(kernel))]
-use proc_macro2 as proc_macro;
-
-use proc_macro::{TokenStream, TokenTree};
+use proc_macro2::{TokenStream, TokenTree};

/// Parsed generics.
///
diff --git a/rust/pin-init/internal/src/lib.rs b/rust/pin-init/internal/src/lib.rs
index 297b0129a5bfd..4c4dc639ce823 100644
--- a/rust/pin-init/internal/src/lib.rs
+++ b/rust/pin-init/internal/src/lib.rs
@@ -7,27 +7,11 @@
//! `pin-init` proc macros.

#![cfg_attr(not(RUSTC_LINT_REASONS_IS_STABLE), feature(lint_reasons))]
-// Allow `.into()` to convert
-// - `proc_macro2::TokenStream` into `proc_macro::TokenStream` in the user-space version.
-// - `proc_macro::TokenStream` into `proc_macro::TokenStream` in the kernel version.
-// Clippy warns on this conversion, but it's required by the user-space version.
-//
-// Remove once we have `proc_macro2` in the kernel.
-#![allow(clippy::useless_conversion)]
// Documentation is done in the pin-init crate instead.
#![allow(missing_docs)]

use proc_macro::TokenStream;

-#[cfg(kernel)]
-#[path = "../../../macros/quote.rs"]
-#[macro_use]
-#[cfg_attr(not(kernel), rustfmt::skip)]
-mod quote;
-#[cfg(not(kernel))]
-#[macro_use]
-extern crate quote;
-
mod helpers;
mod pin_data;
mod pinned_drop;
diff --git a/rust/pin-init/internal/src/pin_data.rs b/rust/pin-init/internal/src/pin_data.rs
index 87d4a7eb1d35e..12d9b02c38837 100644
--- a/rust/pin-init/internal/src/pin_data.rs
+++ b/rust/pin-init/internal/src/pin_data.rs
@@ -1,10 +1,8 @@
// SPDX-License-Identifier: Apache-2.0 OR MIT

-#[cfg(not(kernel))]
-use proc_macro2 as proc_macro;
-
use crate::helpers::{parse_generics, Generics};
-use proc_macro::{Group, Punct, Spacing, TokenStream, TokenTree};
+use proc_macro2::{Group, Punct, Spacing, TokenStream, TokenTree};
+use quote::quote;

pub(crate) fn pin_data(args: TokenStream, input: TokenStream) -> TokenStream {
// This proc-macro only does some pre-parsing and then delegates the actual parsing to
diff --git a/rust/pin-init/internal/src/pinned_drop.rs b/rust/pin-init/internal/src/pinned_drop.rs
index c4ca7a70b726a..978c2594243ba 100644
--- a/rust/pin-init/internal/src/pinned_drop.rs
+++ b/rust/pin-init/internal/src/pinned_drop.rs
@@ -1,9 +1,7 @@
// SPDX-License-Identifier: Apache-2.0 OR MIT

-#[cfg(not(kernel))]
-use proc_macro2 as proc_macro;
-
-use proc_macro::{TokenStream, TokenTree};
+use proc_macro2::{TokenStream, TokenTree};
+use quote::quote;

pub(crate) fn pinned_drop(_args: TokenStream, input: TokenStream) -> TokenStream {
let mut toks = input.into_iter().collect::<Vec<_>>();
diff --git a/rust/pin-init/internal/src/zeroable.rs b/rust/pin-init/internal/src/zeroable.rs
index e0ed3998445cf..d8a5ef3883f4b 100644
--- a/rust/pin-init/internal/src/zeroable.rs
+++ b/rust/pin-init/internal/src/zeroable.rs
@@ -1,10 +1,8 @@
// SPDX-License-Identifier: GPL-2.0

-#[cfg(not(kernel))]
-use proc_macro2 as proc_macro;
-
use crate::helpers::{parse_generics, Generics};
-use proc_macro::{TokenStream, TokenTree};
+use proc_macro2::{TokenStream, TokenTree};
+use quote::quote;

pub(crate) fn parse_zeroable_derive_input(
input: TokenStream,
diff --git a/scripts/generate_rust_analyzer.py b/scripts/generate_rust_analyzer.py
index 147d0cc940681..d31d938886589 100755
--- a/scripts/generate_rust_analyzer.py
+++ b/scripts/generate_rust_analyzer.py
@@ -123,7 +123,7 @@ def generate_crates(srctree, objtree, sysroot_src, external_src, cfgs, core_edit
append_crate(
"pin_init_internal",
srctree / "rust" / "pin-init" / "internal" / "src" / "lib.rs",
- [],
+ ["std", "proc_macro", "proc_macro2", "quote", "syn"],
cfg=["kernel"],
is_proc_macro=True,
)
--
2.51.2