Re: [PATCH v3 3/4] mm/gup: remove unused pin_user_pages_locked()

[Claudio Imbrenda]

On Thu, 3 Feb 2022 01:32:31 -0800
John Hubbard <jhubbard@xxxxxxxxxx> wrote:

> This routine was used for a short while, but then the calling code was
> refactored and the only caller was removed.
> 
> Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
> Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
> Reviewed-by: Jan Kara <jack@xxxxxxx>
> Reviewed-by: Christoph Hellwig <hch@xxxxxx>
> Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>

if it's not used anymore, good riddance

Reviewed-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>

> ---
>  include/linux/mm.h |  2 --
>  mm/gup.c           | 29 -----------------------------
>  2 files changed, 31 deletions(-)
> 
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 213cc569b192..80c540c17d83 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -1918,8 +1918,6 @@ long pin_user_pages(unsigned long start, unsigned long nr_pages,
>  		    struct vm_area_struct **vmas);
>  long get_user_pages_locked(unsigned long start, unsigned long nr_pages,
>  		    unsigned int gup_flags, struct page **pages, int *locked);
> -long pin_user_pages_locked(unsigned long start, unsigned long nr_pages,
> -		    unsigned int gup_flags, struct page **pages, int *locked);
>  long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
>  		    struct page **pages, unsigned int gup_flags);
>  long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
> diff --git a/mm/gup.c b/mm/gup.c
> index cad3f28492e3..b0ecbfe03928 100644
> --- a/mm/gup.c
> +++ b/mm/gup.c
> @@ -3119,32 +3119,3 @@ long pin_user_pages_unlocked(unsigned long start, unsigned long nr_pages,
>  	return get_user_pages_unlocked(start, nr_pages, pages, gup_flags);
>  }
>  EXPORT_SYMBOL(pin_user_pages_unlocked);
> -
> -/*
> - * pin_user_pages_locked() is the FOLL_PIN variant of get_user_pages_locked().
> - * Behavior is the same, except that this one sets FOLL_PIN and rejects
> - * FOLL_GET.
> - */
> -long pin_user_pages_locked(unsigned long start, unsigned long nr_pages,
> -			   unsigned int gup_flags, struct page **pages,
> -			   int *locked)
> -{
> -	/*
> -	 * FIXME: Current FOLL_LONGTERM behavior is incompatible with
> -	 * FAULT_FLAG_ALLOW_RETRY because of the FS DAX check requirement on
> -	 * vmas.  As there are no users of this flag in this call we simply
> -	 * disallow this option for now.
> -	 */
> -	if (WARN_ON_ONCE(gup_flags & FOLL_LONGTERM))
> -		return -EINVAL;
> -
> -	/* FOLL_GET and FOLL_PIN are mutually exclusive. */
> -	if (WARN_ON_ONCE(gup_flags & FOLL_GET))
> -		return -EINVAL;
> -
> -	gup_flags |= FOLL_PIN;
> -	return __get_user_pages_locked(current->mm, start, nr_pages,
> -				       pages, NULL, locked,
> -				       gup_flags | FOLL_TOUCH);
> -}
> -EXPORT_SYMBOL(pin_user_pages_locked);