Re: [PATCH] mm: adjust get_page()'s types

[Julien Grall <julien@xxxxxxx>]

Hi Jan,

On 16/09/2020 08:28, Jan Beulich wrote:
> The passed in domain doesn't get altered and hence can be const. While
> modifying its prototype anyway, also switch to bool.
Reviewed-by: Julien Grall <jgrall@xxxxxxxxxx>

Cheers,

> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
>
> --- a/xen/arch/arm/mm.c
> +++ b/xen/arch/arm/mm.c
> @@ -1560,17 +1560,17 @@ void put_page(struct page_info *page)
>       }
>   }
>   
> -int get_page(struct page_info *page, struct domain *domain)
> +bool get_page(struct page_info *page, const struct domain *domain)
>   {
> -    struct domain *owner = page_get_owner_and_reference(page);
> +    const struct domain *owner = page_get_owner_and_reference(page);
>   
>       if ( likely(owner == domain) )
> -        return 1;
> +        return true;
>   
>       if ( owner != NULL )
>           put_page(page);
>   
> -    return 0;
> +    return false;
>   }
>   
>   /* Common code requires get_page_type and put_page_type.
> --- a/xen/arch/x86/mm.c
> +++ b/xen/arch/x86/mm.c
> @@ -2510,12 +2510,12 @@ struct domain *page_get_owner_and_refere
>   }
>   
>   
> -int get_page(struct page_info *page, struct domain *domain)
> +bool get_page(struct page_info *page, const struct domain *domain)
>   {
> -    struct domain *owner = page_get_owner_and_reference(page);
> +    const struct domain *owner = page_get_owner_and_reference(page);
>   
>       if ( likely(owner == domain) )
> -        return 1;
> +        return true;
>   
>       if ( !paging_mode_refcounts(domain) && !domain->is_dying )
>           gprintk(XENLOG_INFO,
> @@ -2526,7 +2526,7 @@ int get_page(struct page_info *page, str
>       if ( owner )
>           put_page(page);
>   
> -    return 0;
> +    return false;
>   }
>   
>   /*
> --- a/xen/include/xen/mm.h
> +++ b/xen/include/xen/mm.h
> @@ -151,7 +151,7 @@ TYPE_SAFE(unsigned long, pfn);
>   struct page_info;
>   
>   void put_page(struct page_info *);
> -int get_page(struct page_info *, struct domain *);
> +bool get_page(struct page_info *, const struct domain *);
>   struct domain *__must_check page_get_owner_and_reference(struct page_info *);
>   
>   /* Boot-time allocator. Turns into generic allocator after bootstrap. */
--
Julien Grall