thp: introduce pmdp_invalidate()
On s390, a valid page table entry must not be changed while it is attached
to any CPU. So instead of pmd_mknotpresent() and set_pmd_at(), an IDTE
operation would be necessary there. This patch introduces the
pmdp_invalidate() function, to allow architecture-specific
implementations.
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c
index 29867e0..e642627 100644
--- a/mm/pgtable-generic.c
+++ b/mm/pgtable-generic.c
@@ -159,3 +159,14 @@
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
#endif
+
+#ifndef __HAVE_ARCH_PMDP_INVALIDATE
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
+ pmd_t *pmdp)
+{
+ set_pmd_at(vma->vm_mm, address, pmdp, pmd_mknotpresent(*pmdp));
+ flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
+}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+#endif