mm: Introduce kvcalloc()

The kv*alloc()-family was missing kvcalloc(). Adding this allows for
2-argument multiplication conversions of kvzalloc(a * b, ...) into
kvcalloc(a, b, ...).

Signed-off-by: Kees Cook <keescook@chromium.org>
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 0e49388..a0fbb9f 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -575,6 +575,11 @@ static inline void *kvmalloc_array(size_t n, size_t size, gfp_t flags)
 	return kvmalloc(bytes, flags);
 }
 
+static inline void *kvcalloc(size_t n, size_t size, gfp_t flags)
+{
+	return kvmalloc_array(n, size, flags | __GFP_ZERO);
+}
+
 extern void kvfree(const void *addr);
 
 static inline atomic_t *compound_mapcount_ptr(struct page *page)