Re: [PATCH] mm/highmem: Fix kernel-doc warnings in highmem*.h

[Mike Rapoport <rppt@kernel.org>]

Hi,

On Mon, Apr 18, 2022 at 09:53:04AM +0200, Fabio M. De Francesco wrote:
> `scripts/kernel-doc -none include/linux/highmem*` reports the following
> warnings:
> 
> include/linux/highmem.h:160: warning: expecting prototype for kunmap_atomic(). Prototype was for nr_free_highpages() instead
> include/linux/highmem-internal.h:256: warning: Function parameter or member '__addr' not described in 'kunmap_atomic'
> include/linux/highmem-internal.h:256: warning: Excess function parameter 'addr' description in 'kunmap_atomic'
> 
> Fix these warnings by (1) move the kernel-doc comments from highmem.h to
> highmem-internal.h (which is the file were the kunmap_atomic() macro is
> actually defined), merge it with the comment which already was in

                   ^ (2) ?

> highmem-internal.h, and (3) replace "@addr" with "@__addr".

There is also replacement of "addr" with "page", so I'd phrase (3) as
"use correct parameter names"
 
> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>

Other than that

Acked-by: Mike Rapoport <rppt@linux.ibm.com>

> ---
>  include/linux/highmem-internal.h | 14 +++++++++++---
>  include/linux/highmem.h          | 13 +------------
>  2 files changed, 12 insertions(+), 15 deletions(-)
> 
> diff --git a/include/linux/highmem-internal.h b/include/linux/highmem-internal.h
> index a77be5630209..7307de391288 100644
> --- a/include/linux/highmem-internal.h
> +++ b/include/linux/highmem-internal.h
> @@ -236,9 +236,17 @@ static inline unsigned long totalhigh_pages(void) { return 0UL; }
>  
>  #endif /* CONFIG_HIGHMEM */
>  
> -/*
> - * Prevent people trying to call kunmap_atomic() as if it were kunmap()
> - * kunmap_atomic() should get the return value of kmap_atomic, not the page.
> +/**
> + * kunmap_atomic - Unmap the virtual address mapped by kmap_atomic()
> + * @__addr:       Virtual address to be unmapped
> + *
> + * Counterpart to kmap_atomic().
> + *
> + * Effectively a wrapper around kunmap_local() which additionally undoes
> + * the side effects of kmap_atomic(), i.e. reenabling pagefaults and
> + * preemption. Prevent people trying to call kunmap_atomic() as if it
> + * were kunmap() because kunmap_atomic() should get the return value of
> + * kmap_atomic(), not its argument which is a pointer to struct page.
>   */
>  #define kunmap_atomic(__addr)					\
>  do {								\
> diff --git a/include/linux/highmem.h b/include/linux/highmem.h
> index 39bb9b47fa9c..0a7a89721e5d 100644
> --- a/include/linux/highmem.h
> +++ b/include/linux/highmem.h
> @@ -37,7 +37,7 @@ static inline void *kmap(struct page *page);
>  
>  /**
>   * kunmap - Unmap the virtual address mapped by kmap()
> - * @addr:	Virtual address to be unmapped
> + * @page:	Virtual address to be unmapped
>   *
>   * Counterpart to kmap(). A NOOP for CONFIG_HIGHMEM=n and for mappings of
>   * pages in the low memory area.
> @@ -145,17 +145,6 @@ static inline void *kmap_local_folio(struct folio *folio, size_t offset);
>   */
>  static inline void *kmap_atomic(struct page *page);
>  
> -/**
> - * kunmap_atomic - Unmap the virtual address mapped by kmap_atomic()
> - * @addr:	Virtual address to be unmapped
> - *
> - * Counterpart to kmap_atomic().
> - *
> - * Effectively a wrapper around kunmap_local() which additionally undoes
> - * the side effects of kmap_atomic(), i.e. reenabling pagefaults and
> - * preemption.
> - */
> -
>  /* Highmem related interfaces for management code */
>  static inline unsigned int nr_free_highpages(void);
>  static inline unsigned long totalhigh_pages(void);
> -- 
> 2.34.1
> 
> 

-- 
Sincerely yours,
Mike.