+static inline void prep_zero_page(struct page *page, int order, gfp_t gfp_flags)
+{
+ int i;
+
+ BUG_ON((gfp_flags & (__GFP_WAIT | __GFP_HIGHMEM)) == __GFP_HIGHMEM);
+ /*
+ * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
+ * and __GFP_HIGHMEM from hard or soft interrupt context.
+ */
+ BUG_ON((gfp_flags & __GFP_HIGHMEM) && in_interrupt());
+ for (i = 0; i < (1 << order); i++)
+ clear_highpage(page + i);
+}
+