thp: pte alloc trans splitting

pte alloc routines must wait for split_huge_page if the pmd is not present
and not null (i.e.  pmd_trans_splitting).  The additional branches are
optimized away at compile time by pmd_trans_splitting if the config option
is off.  However we must pass the vma down in order to know the anon_vma
lock to wait for.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
index c2f1b26..998e972 100644
--- a/arch/x86/kernel/tboot.c
+++ b/arch/x86/kernel/tboot.c
@@ -133,7 +133,7 @@
 	pmd = pmd_alloc(&tboot_mm, pud, vaddr);
 	if (!pmd)
 		return -1;
-	pte = pte_alloc_map(&tboot_mm, pmd, vaddr);
+	pte = pte_alloc_map(&tboot_mm, NULL, pmd, vaddr);
 	if (!pte)
 		return -1;
 	set_pte_at(&tboot_mm, vaddr, pte, pfn_pte(pfn, prot));