On Fri, Mar 14, 2025 at 09:42:34PM -0500, Andrew Ballance wrote:
> implemnts the equivalent of the rust std's Vec::resize
> on the kernel's Vec type.
Nit: It is preferred to use the imperative form, i.e. "Implement the equivalent
[...]".
>
> Signed-off-by: Andrew Ballance
> ---
> rust/kernel/alloc/kvec.rs | 25 +
> 1 file changed, 25 insertions(+)
>
> diff --git a/rust/kernel/alloc/kvec.rs b/rust/kernel/alloc/kvec.rs
> index 75e9feebb81f..cbfef2e56f9c 100644
> --- a/rust/kernel/alloc/kvec.rs
> +++ b/rust/kernel/alloc/kvec.rs
> @@ -554,6 +554,31 @@ pub fn from_elem(value: T, n: usize, flags: Flags) ->
> Result {
>
> Ok(v)
> }
> +
> +/// Resizes the [`Vec`] so that `len` is equal to `new_len`.
> +///
> +/// If `new_len` is smaller than `len`, the `Vec` is [`Vec::truncate`]d.
> +/// If `new_len` is larger, each new slot is filled with clones of
> `value`.
> +///
> +/// # Example
Nit: Please add an empty line after the heading.
> +/// ```
> +/// let mut v = kernel::kvec![1, 2, 3]?;
> +/// v.resize(1, 42, GFP_KERNEL)?;
> +/// assert_eq!(&v, &[1]);
> +///
> +/// v.resize(3, 42, GFP_KERNEL)?;
> +/// assert_eq!(&v, &[1, 42, 42]);
> +///
> +/// # Ok::<(), Error>(())
> +/// ```
> +pub fn resize(&mut self, new_len: usize, value: T, flags: Flags) ->
> Result<(), AllocError> {
> +if new_len > self.len() {
> +self.extend_with(new_len - self.len(), value, flags)
> +} else {
> +self.truncate(new_len);
> +Ok(())
> +}
> +}
> }
>
> impl Drop for Vec
> --
> 2.48.1
>
