Re: [PATCH v4 1/4] rust: iov: add iov_iter abstractions for ITER_SOURCE

["Danilo Krummrich" <dakr@kernel.org>]

On Wed Aug 13, 2025 at 10:27 AM CEST, Alice Ryhl wrote:
> +    /// Read data from this IO vector and append it to a vector.
> +    ///
> +    /// Returns the number of bytes that have been copied.
> +    #[inline]
> +    pub fn copy_from_iter_vec<A: Allocator>(
> +        &mut self,
> +        out: &mut Vec<u8, A>,
> +        flags: Flags,
> +    ) -> Result<usize> {
> +        out.reserve(self.len(), flags)?;
> +        let len = self.copy_from_iter_raw(out.spare_capacity_mut()).len();
> +        // SAFETY: `Self::copy_from_iter_raw` guarantees that the first `len` bytes of the spare
> +        // capacity have been initialized.

Technically, this covers the safety requirements from inc_len(). However, do we
want to provide a list of justifications if the unsafe functions has a list of
requirements, such that they are easier to match?

> +        unsafe { out.inc_len(len) };
> +        Ok(len)
> +    }

Either way,

Reviewed-by: Danilo Krummrich <dakr@kernel.org>