On Thu, Apr 21, 2022 at 08:01:57PM +0200, Fabio M. De Francesco wrote:
> `scripts/kernel-doc -v -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.h:204: warning: No description found for return value of 'alloc_zeroed_user_highpage_movable'
> 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) moving the kernel-doc comments from highmem.h to
> highmem-internal.h (which is the file were the kunmap_atomic() macro is
> actually defined), (2) extending and merging it with the comment which was
> already in highmem-internal.h, and (3) using correct parameter names.
>
> Cc: Mike Rapoport <rppt@xxxxxxxxxxxxx>
> Cc: Ira Weiny <ira.weiny@xxxxxxxxx>
> Suggested-by: Matthew Wilcox <willy@xxxxxxxxxxxxx>
> Signed-off-by: Fabio M. De Francesco <fmdefrancesco@xxxxxxxxx>
> ---
> include/linux/highmem-internal.h | 14 +++++++++++---
> include/linux/highmem.h | 15 +++------------
> 2 files changed, 14 insertions(+), 15 deletions(-)
>
> diff --git a/include/linux/highmem-internal.h b/include/linux/highmem-internal.h
> index a77be5630209..b099a08e29d3 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
> + *
> + * Unmap an address previously mapped by kmap_atomic() and re-enables
Unmap ... and re-enable
or
Unmaps ... and re-enables
Other than that
Acked-by: Mike Rapoport <rppt@xxxxxxxxxxxxx>
> + * pagefaults and preemption. Mappings should be unmapped in the reverse
> + * order that they were mapped. See kmap_local_page() for details.
> + * @__addr can be any address within the mapped page, so there is no need
> + * to subtract any offset that has been added. In contrast to kunmap(),
> + * this function takes the address returned from kmap_atomic(), not the
> + * page passed to it. The compiler will warn you if you pass the page.
> */
> #define kunmap_atomic(__addr) \
> do { \
> diff --git a/include/linux/highmem.h b/include/linux/highmem.h
> index 39bb9b47fa9c..c3d562b5f0c1 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);
> @@ -191,6 +180,8 @@ static inline void clear_user_highpage(struct page *page, unsigned long vaddr)
> * @vma: The VMA the page is to be allocated for
> * @vaddr: The virtual address the page will be inserted into
> *
> + * Returns: The allocated and zeroed HIGHMEM page
> + *
> * This function will allocate a page for a VMA that the caller knows will
> * be able to migrate in the future using move_pages() or reclaimed
> *
> --
> 2.34.1
>
>
--
Sincerely yours,
Mike.
