hugetlb: add phys addr to struct huge_bootmem_page

This is needed on HIGHMEM systems - we don't always have a virtual
address so store the physical address and map it in as needed.

[akpm@linux-foundation.org: cleanup]
Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/hugetlb.h

@@ -231,6 +231,9 @@ struct hstate {
 struct huge_bootmem_page {
 	struct list_head list;
 	struct hstate *hstate;
+#ifdef CONFIG_HIGHMEM
+	phys_addr_t phys;
+#endif
 };
 
 struct page *alloc_huge_page_node(struct hstate *h, int nid);