Re: [PATCH] rust: page: add `from_raw()`

["Gary Guo" <gary@garyguo.net>]

On Wed Jan 28, 2026 at 1:22 PM GMT, Andreas Hindborg wrote:
> Add a method to `Page` that allows construction of a reference instance
> from `struct page` pointer.
>
> Signed-off-by: Andreas Hindborg <a.hindborg@samsung.com>
> ---
> Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
> ---
>  rust/kernel/page.rs | 11 +++++++++++
>  1 file changed, 11 insertions(+)
>
> diff --git a/rust/kernel/page.rs b/rust/kernel/page.rs
> index 432fc0297d4a8..f666c92fcf451 100644
> --- a/rust/kernel/page.rs
> +++ b/rust/kernel/page.rs
> @@ -176,6 +176,17 @@ pub fn nid(&self) -> i32 {
>          unsafe { bindings::page_to_nid(self.as_ptr()) }
>      }
>  
> +    /// Create a `&Page` from a raw `struct page` pointer
> +    ///
> +    /// # Safety
> +    ///
> +    /// `ptr` must be valid for use as a reference for the duration of `'a`.
> +    pub unsafe fn from_raw<'a>(ptr: *mut bindings::page) -> &'a Self {
> +        // SAFETY: By function safety requirements, ptr is not null and is
> +        // valid for use as a reference.
> +        unsafe { NonNull::new_unchecked(ptr).cast().as_ref() }
> +    }

This is wrong. `Page` is a wrapper of `struct page*`, not `struct page`.

Best,
Gary

> +
>      /// Runs a piece of code with this page mapped to an address.
>      ///
>      /// The page is unmapped when this call returns.
>
> ---
> base-commit: 63804fed149a6750ffd28610c5c1c98cce6bd377
> change-id: 20260128-page-from-raw-e8e1f14e3f6d
>
> Best regards,