mm: convert p[te|md]_mknonnuma and remaining page table manipulations

With PROT_NONE, the traditional page table manipulation functions are
sufficient.

[andre.przywara@arm.com: fix compiler warning in pmdp_invalidate()]
[akpm@linux-foundation.org: fix build with STRICT_MM_TYPECHECKS]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 4 deletions

diff --git a/mm/memory.c b/mm/memory.c
index 92e6a6299e86..d7921760cf79 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3018,9 +3018,9 @@ static int do_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
         * validation through pte_unmap_same(). It's of NUMA type but
         * the pfn may be screwed if the read is non atomic.
         *
-        * ptep_modify_prot_start is not called as this is clearing
-        * the _PAGE_NUMA bit and it is not really expected that there
-        * would be concurrent hardware modifications to the PTE.
+        * We can safely just do a "set_pte_at()", because the old
+        * page table entry is not accessible, so there would be no
+        * concurrent hardware modifications to the PTE.
         */
         ptl = pte_lockptr(mm, pmd);
         spin_lock(ptl);
@@ -3029,7 +3029,9 @@ static int do_numa_page(struct mm_struct *mm, struct vm_area_struct *vma,
                 goto out;
         }
 
-        pte = pte_mknonnuma(pte);
+        /* Make it present again */
+        pte = pte_modify(pte, vma->vm_page_prot);
+        pte = pte_mkyoung(pte);
         set_pte_at(mm, addr, ptep, pte);
         update_mmu_cache(vma, addr, ptep);