thp: compound_trans_order

Read compound_trans_order safe. Noop for CONFIG_TRANSPARENT_HUGEPAGE=n.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 1b43d0f..548fbd7 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -203,7 +203,7 @@
 #ifdef __ARCH_SI_TRAPNO
 	si.si_trapno = trapno;
 #endif
-	si.si_addr_lsb = compound_order(compound_head(page)) + PAGE_SHIFT;
+	si.si_addr_lsb = compound_trans_order(compound_head(page)) + PAGE_SHIFT;
 	/*
 	 * Don't use force here, it's convenient if the signal
 	 * can be temporarily blocked.
@@ -930,7 +930,7 @@
 static void set_page_hwpoison_huge_page(struct page *hpage)
 {
 	int i;
-	int nr_pages = 1 << compound_order(hpage);
+	int nr_pages = 1 << compound_trans_order(hpage);
 	for (i = 0; i < nr_pages; i++)
 		SetPageHWPoison(hpage + i);
 }
@@ -938,7 +938,7 @@
 static void clear_page_hwpoison_huge_page(struct page *hpage)
 {
 	int i;
-	int nr_pages = 1 << compound_order(hpage);
+	int nr_pages = 1 << compound_trans_order(hpage);
 	for (i = 0; i < nr_pages; i++)
 		ClearPageHWPoison(hpage + i);
 }
@@ -968,7 +968,7 @@
 		return 0;
 	}
 
-	nr_pages = 1 << compound_order(hpage);
+	nr_pages = 1 << compound_trans_order(hpage);
 	atomic_long_add(nr_pages, &mce_bad_pages);
 
 	/*
@@ -1166,7 +1166,7 @@
 		return 0;
 	}
 
-	nr_pages = 1 << compound_order(page);
+	nr_pages = 1 << compound_trans_order(page);
 
 	if (!get_page_unless_zero(page)) {
 		/*
@@ -1304,7 +1304,7 @@
 	}
 done:
 	if (!PageHWPoison(hpage))
-		atomic_long_add(1 << compound_order(hpage), &mce_bad_pages);
+		atomic_long_add(1 << compound_trans_order(hpage), &mce_bad_pages);
 	set_page_hwpoison_huge_page(hpage);
 	dequeue_hwpoisoned_huge_page(hpage);
 	/* keep elevated page count for bad page */