From: Peter Xu <pet...@redhat.com>

Currently there should have no p4d swap entries so it may not matter much,
however this may help us to rule out swap entries in pXd_huge() API, which
will include p4d_huge().  The p4d_present() checks make it 100% clear that
we won't rely on p4d_huge() for swap entries.

Signed-off-by: Peter Xu <pet...@redhat.com>
---
 mm/gup.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/gup.c b/mm/gup.c
index 69a777f4fc5c..802987281b2f 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -776,7 +776,7 @@ static struct page *follow_p4d_mask(struct vm_area_struct 
*vma,
 
        p4dp = p4d_offset(pgdp, address);
        p4d = READ_ONCE(*p4dp);
-       if (p4d_none(p4d))
+       if (!p4d_present(p4d))
                return no_page_table(vma, flags);
        BUILD_BUG_ON(p4d_huge(p4d));
        if (unlikely(p4d_bad(p4d)))
@@ -3069,7 +3069,7 @@ static int gup_p4d_range(pgd_t *pgdp, pgd_t pgd, unsigned 
long addr, unsigned lo
                p4d_t p4d = READ_ONCE(*p4dp);
 
                next = p4d_addr_end(addr, end);
-               if (p4d_none(p4d))
+               if (!p4d_present(p4d))
                        return 0;
                BUILD_BUG_ON(p4d_huge(p4d));
                if (unlikely(is_hugepd(__hugepd(p4d_val(p4d))))) {
-- 
2.44.0

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