gru: add hugepage support

Add support for hugepages. Easier than I originally thought.
Signed-off-by: NJack Steiner <steiner@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/misc/sgi-gru/grufault.c

@@ -192,10 +192,11 @@ static int non_atomic_pte_lookup(struct vm_area_struct *vma,
 {
 	struct page *page;
 
-	/* ZZZ Need to handle HUGE pages */
-	if (is_vm_hugetlb_page(vma))
-		return -EFAULT;
+#ifdef CONFIG_HUGETLB_PAGE
+	*pageshift = is_vm_hugetlb_page(vma) ? HPAGE_SHIFT : PAGE_SHIFT;
+#else
 	*pageshift = PAGE_SHIFT;
+#endif
 	if (get_user_pages
 	    (current, current->mm, vaddr, 1, write, 0, &page, NULL) <= 0)
 		return -EFAULT;