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>
---
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
