On Sun, Jul 21, 2019 at 03:46:11AM -0700, Matthew Wilcox wrote:
> From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
>
> Replace PAGE_SHIFT + compound_order(page) with the new page_shift()
> function. Minor improvements in readability.
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: Ira Weiny <ira.weiny@xxxxxxxxx>
> ---
> arch/powerpc/mm/book3s64/iommu_api.c | 7 ++-----
> drivers/vfio/vfio_iommu_spapr_tce.c | 2 +-
> include/linux/mm.h | 6 ++++++
> 3 files changed, 9 insertions(+), 6 deletions(-)
>
> diff --git a/arch/powerpc/mm/book3s64/iommu_api.c b/arch/powerpc/mm/book3s64/iommu_api.c
> index b056cae3388b..56cc84520577 100644
> --- a/arch/powerpc/mm/book3s64/iommu_api.c
> +++ b/arch/powerpc/mm/book3s64/iommu_api.c
> @@ -129,11 +129,8 @@ static long mm_iommu_do_alloc(struct mm_struct *mm, unsigned long ua,
> * Allow to use larger than 64k IOMMU pages. Only do that
> * if we are backed by hugetlb.
> */
> - if ((mem->pageshift > PAGE_SHIFT) && PageHuge(page)) {
> - struct page *head = compound_head(page);
> -
> - pageshift = compound_order(head) + PAGE_SHIFT;
> - }
> + if ((mem->pageshift > PAGE_SHIFT) && PageHuge(page))
> + pageshift = page_shift(compound_head(page));
> mem->pageshift = min(mem->pageshift, pageshift);
> /*
> * We don't need struct page reference any more, switch
> diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c
> index 8ce9ad21129f..1883fd2901b2 100644
> --- a/drivers/vfio/vfio_iommu_spapr_tce.c
> +++ b/drivers/vfio/vfio_iommu_spapr_tce.c
> @@ -190,7 +190,7 @@ static bool tce_page_is_contained(struct mm_struct *mm, unsigned long hpa,
> * a page we just found. Otherwise the hardware can get access to
> * a bigger memory chunk that it should.
> */
> - return (PAGE_SHIFT + compound_order(compound_head(page))) >= page_shift;
> + return page_shift(compound_head(page)) >= page_shift;
> }
>
> static inline bool tce_groups_attached(struct tce_container *container)
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 899dfcf7c23d..64762559885f 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -811,6 +811,12 @@ static inline unsigned long page_size(struct page *page)
> return PAGE_SIZE << compound_order(page);
> }
>
> +/* Returns the number of bits needed for the number of bytes in a page */
> +static inline unsigned int page_shift(struct page *page)
> +{
> + return PAGE_SHIFT + compound_order(page);
> +}
> +
> void free_compound_page(struct page *page);
>
> #ifdef CONFIG_MMU
> --
> 2.20.1
>
