[PATCH v1 12/18] sh/mm/cache: use folio_mapped() in copy_from_user_page()

David Hildenbrand
2024-04-09T19:26:03Z

We want to limit the use of page_mapcount() to the places where it is
absolutely necessary.

We're already using folio_mapped in copy_user_highpage() and
copy_to_user_page() for a similar purpose so ... let's also simply use
it for copy_from_user_page().

There is no change for small folios. Likely we won't stumble over many
large folios on sh in that code either way.

Signed-off-by: David Hildenbrand <david@redhat.com>
---
arch/sh/mm/cache.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/sh/mm/cache.c b/arch/sh/mm/cache.c
index 9bcaa5619eab..d8be352e14d2 100644
--- a/arch/sh/mm/cache.c
+++ b/arch/sh/mm/cache.c
@@ -84,7 +84,7 @@ void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
{
struct folio *folio = page_folio(page);

- if (boot_cpu_data.dcache.n_aliases && page_mapcount(page) &&
+ if (boot_cpu_data.dcache.n_aliases && folio_mapped(folio) &&
test_bit(PG_dcache_clean, &folio->flags)) {
void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
memcpy(dst, vfrom, len);
--
2.44.0