[PATCH] s390: add missing pte_read function

this patch adds the missing pte_read function and makes s390 compile again.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/asm-s390/pgtable.h

@@ -418,6 +418,14 @@ extern inline int pte_young(pte_t pte)
 	return 0;
 }
 
+extern inline int pte_read(pte_t pte)
+{
+	/* All pages are readable since we don't use the fetch
+	 * protection bit in the storage key.
+	 */
+	return 1;
+}
+
 /*
  * pgd/pmd/pte modification functions
  */