kernel/linux.git/rust/helpers/uaccess.c, branch v7.2-rc2

uaccess: unify inline vs outline copy_{from,to}_user() selection

2026-05-29T04:24:44+00:00

The kernel allows arches to select between inline and outline implementations of the copy_{from,to}_user() by defining individual INLINE_COPY_FROM_USER and INLINE_COPY_TO_USER, correspondingly. However, all arches enable or disable them always together. Without the real use-case for one helper being inlined while the other outlined, having independent controls is excessive and error prone. Switch the codebase to the single unified INLINE_COPY_USER control. Link: https://lore.kernel.org/20260425020857.356850-3-ynorov@nvidia.com Signed-off-by: Yury Norov Tested-by: Alice Ryhl Cc: Arnd Bergmann Cc: Christophe Leroy (CS GROUP) Cc: Mathieu Desnoyers Cc: Peter Zijlstra Cc: Randy Dunlap Cc: Viktor Malik Signed-off-by: Andrew Morton

rust: uaccess: use INLINE_COPY_TO_USER to guard copy_to_user()

2026-05-29T04:24:44+00:00

Patch series "uaccess: unify inline vs outline copy_{from,to}_user() selection", v2. The kernel allows arches to select between inline and outline implementations of the copy_{from,to}_user() by defining individual INLINE_COPY_FROM_USER and INLINE_COPY_TO_USER, correspondingly. However, all arches enable or disable them always together. Without the real use-case for one helper being inlined while the other outlined, having independent controls is excessive and error prone. The first patch of the series fixes rust/uaccess coppy_to_user() wrapper guarded with INLINE_COPY_FROM_USER. The 2nd patch switches codebase to the unified INLINE_COPY_USER. And the last patch cleans up ifdefery in the include/linux/uaccess.h This patch (of 3): The copy_to_user() rust helper is only needed when the main kernel inlines the function. It is controlled by INLINE_COPY_TO_USER, but the rust helper is protected with INLINE_COPY_FROM_USER. Fix that. Link: https://lore.kernel.org/20260425020857.356850-1-ynorov@nvidia.com Link: https://lore.kernel.org/20260425020857.356850-2-ynorov@nvidia.com Fixes: d99dc586ca7c7 ("uaccess: decouple INLINE_COPY_FROM_USER and CONFIG_RUST") Signed-off-by: Yury Norov Reported-by: Christophe Leroy (CS GROUP) Closes: https://lore.kernel.org/all/746c9c50-20c4-4dc9-a539-bf1310ff9414@kernel.org/ Cc: Alice Ryhl Cc: Mathieu Desnoyers Cc: Peter Zijlstra Cc: Randy Dunlap Cc: Viktor Malik Cc: Arnd Bergmann Signed-off-by: Andrew Morton

rust: uaccess: add __rust_helper to helpers

2026-01-26T02:51:16+00:00

This is needed to inline these helpers into Rust code. Reviewed-by: Boqun Feng Reviewed-by: Gary Guo Signed-off-by: Alice Ryhl Link: https://patch.msgid.link/20260105-define-rust-helper-v2-23-51da5f454a67@google.com Signed-off-by: Miguel Ojeda

uaccess: decouple INLINE_COPY_FROM_USER and CONFIG_RUST

2025-11-12T18:00:16+00:00

Commit 1f9a8286bc0c ("uaccess: always export _copy_[from|to]_user with CONFIG_RUST") exports _copy_{from,to}_user() unconditionally, if RUST is enabled. This pollutes exported symbols namespace, and spreads RUST ifdefery in core files. It's better to declare a corresponding helper under the rust/helpers, similarly to how non-underscored copy_{from,to}_user() is handled. [yury.norov@gmail.com: drop rust part of comment for _copy_from_user(), per Alice] Link: https://lkml.kernel.org/r/20251024154754.99768-1-yury.norov@gmail.com Link: https://lkml.kernel.org/r/20251023171607.1171534-1-yury.norov@gmail.com Signed-off-by: Yury Norov (NVIDIA) Acked-by: Arnd Bergmann Acked-by: Miguel Ojeda Reviewed-by: Alice Ryhl Tested-by: Alice Ryhl Cc: Alex Gaynor Cc: Andreas Hindborg Cc: Björn Roy Baron Cc: Boqun Feng Cc: Danilo Krummrich Cc: Gary Guo Cc: John Hubbard Cc: Trevor Gross Signed-off-by: Andrew Morton

rust: kbuild: auto generate helper exports

2024-08-19T09:09:02+00:00

This removes the need to explicitly export all symbols. Generate helper exports similarly to what's currently done for Rust crates. These helpers are exclusively called from within Rust code and therefore can be treated similar as other Rust symbols. Signed-off-by: Gary Guo Reviewed-by: Boqun Feng Tested-by: Boqun Feng Link: https://lore.kernel.org/r/20240817165302.3852499-1-gary@garyguo.net [ Fixed dependency path, reworded slightly, edited comment a bit and rebased on top of the changes made when applying Andreas' patch (e.g. no `README.md` anymore, so moved the edits). - Miguel ] Signed-off-by: Miguel Ojeda

rust: kbuild: split up helpers.c

2024-08-18T21:34:26+00:00

This patch splits up the rust helpers C file. When rebasing patch sets on upstream linux, merge conflicts in helpers.c is common and time consuming [1]. Thus, split the file so that each kernel component can live in a separate file. This patch lists helper files explicitly and thus conflicts in the file list is still likely. However, they should be more simple to resolve than the conflicts usually seen in helpers.c. [ Removed `README.md` and undeleted the original comment since now, in v3 of the series, we have a `helpers.c` again; which also allows us to keep the "Sorted alphabetically" line and makes the diff easier. In addition, updated the Documentation/ mentions of the file, reworded title and removed blank lines at the end of `page.c`. - Miguel ] Link: https://rust-for-linux.zulipchat.com/#narrow/stream/288089-General/topic/Splitting.20up.20helpers.2Ec/near/426694012 [1] Signed-off-by: Andreas Hindborg Reviewed-by: Gary Guo Acked-by: Dirk Behme Reviewed-by: Alice Ryhl Reviewed-by: Benno Lossin Link: https://lore.kernel.org/r/20240815103016.2771842-1-nmi@metaspace.dk Signed-off-by: Miguel Ojeda