Re: [PATCH v2 1/3] rust: helpers: Add list helpers for C linked list operations

From: Alexandre Courbot
Date: Tue Nov 25 2025 - 09:54:59 EST


On Wed Nov 12, 2025 at 2:13 AM JST, Joel Fernandes wrote:
> Add Rust helper functions for common C linked list operations
> that are implemented as macros or inline functions and thus not
> directly accessible from Rust.
>
> Signed-off-by: Joel Fernandes <joelagnelf@xxxxxxxxxx>
> ---
> rust/helpers/helpers.c | 1 +
> rust/helpers/list.c | 32 ++++++++++++++++++++++++++++++++
> 2 files changed, 33 insertions(+)
> create mode 100644 rust/helpers/list.c
>
> diff --git a/rust/helpers/helpers.c b/rust/helpers/helpers.c
> index 79c72762ad9c..634fa2386bbb 100644
> --- a/rust/helpers/helpers.c
> +++ b/rust/helpers/helpers.c
> @@ -32,6 +32,7 @@
> #include "io.c"
> #include "jump_label.c"
> #include "kunit.c"
> +#include "list.c"
> #include "maple_tree.c"
> #include "mm.c"
> #include "mutex.c"
> diff --git a/rust/helpers/list.c b/rust/helpers/list.c
> new file mode 100644
> index 000000000000..fea2a18621da
> --- /dev/null
> +++ b/rust/helpers/list.c
> @@ -0,0 +1,32 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +/*
> + * Helpers for C Circular doubly linked list implementation.
> + */
> +
> +#include <linux/list.h>
> +
> +bool rust_helper_list_empty(const struct list_head *head)
> +{
> + return list_empty(head);
> +}
> +
> +void rust_helper_list_del(struct list_head *entry)
> +{
> + list_del(entry);
> +}
> +
> +void rust_helper_INIT_LIST_HEAD(struct list_head *list)
> +{
> + INIT_LIST_HEAD(list);
> +}
> +
> +void rust_helper_list_add(struct list_head *new, struct list_head *head)
> +{
> + list_add(new, head);
> +}
> +
> +void rust_helper_list_add_tail(struct list_head *new, struct list_head *head)
> +{
> + list_add_tail(new, head);
> +}

Just noticed, but of these helpers only `INIT_LIST_HEAD` and
`list_add_tail` seem to be used (in doccomments).