diff --git a/include/linux/pid_namespace.h b/include/linux/pid_namespace.h
index 215e5e3dda1063e955c93fa566b46de16f6c8dc3..8ac32836690e3a50ce25d89187ac7c42193e8835 100644
--- a/include/linux/pid_namespace.h
+++ b/include/linux/pid_namespace.h
@@ -13,7 +13,9 @@ struct pidmap {
        void *page;
 };
 
-#define PIDMAP_ENTRIES         ((PID_MAX_LIMIT + 8*PAGE_SIZE - 1)/PAGE_SIZE/8)
+#define BITS_PER_PAGE		(PAGE_SIZE * 8)
+#define BITS_PER_PAGE_MASK	(BITS_PER_PAGE-1)
+#define PIDMAP_ENTRIES		((PID_MAX_LIMIT+BITS_PER_PAGE-1)/BITS_PER_PAGE)
 
 struct bsd_acct_struct;
 
diff --git a/kernel/pid.c b/kernel/pid.c
index 8147bdf22f36a498f0ed108be8e50b20d5f02ed5..6283d6412affd58763657141aeec206cb1a32d02 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -51,9 +51,6 @@ int pid_max = PID_MAX_DEFAULT;
 int pid_max_min = RESERVED_PIDS + 1;
 int pid_max_max = PID_MAX_LIMIT;
 
-#define BITS_PER_PAGE		(PAGE_SIZE*8)
-#define BITS_PER_PAGE_MASK	(BITS_PER_PAGE-1)
-
 static inline int mk_pid(struct pid_namespace *pid_ns,
 		struct pidmap *map, int off)
 {
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index bea15bdf82b04c28d2f5d8c1a32a46b2621cb295..69473c4a653f72e47affee5bc71e832336da7f60 100644
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -19,8 +19,6 @@
 #include <linux/reboot.h>
 #include <linux/export.h>
 
-#define BITS_PER_PAGE		(PAGE_SIZE*8)
-
 struct pid_cache {
 	int nr_ids;
 	char name[16];