thp: kvm mmu transparent hugepage support

This should work for both hugetlbfs and transparent hugepages.

[akpm@linux-foundation.org: bring forward PageTransCompound() addition for bisectability]
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 12 insertions, 0 deletions

diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 4835cae71047..907f1605926b 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -409,6 +409,18 @@ static inline void ClearPageCompound(struct page *page)
 
 #endif /* !PAGEFLAGS_EXTENDED */
 
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static inline int PageTransCompound(struct page *page)
+{
+        return PageCompound(page);
+}
+#else
+static inline int PageTransCompound(struct page *page)
+{
+        return 0;
+}
+#endif
+
 #ifdef CONFIG_MMU
 #define __PG_MLOCKED            (1 << PG_mlocked)
 #else