1 files changed, 37 insertions, 0 deletions

diff --git a/arch/s390/include/asm/percpu.h b/arch/s390/include/asm/percpu.h
new file mode 100644
index 000000000000..408d60b4f75b
--- /dev/null
+++ b/arch/s390/include/asm/percpu.h
@@ -0,0 +1,37 @@
+#ifndef __ARCH_S390_PERCPU__
+#define __ARCH_S390_PERCPU__
+
+#include <linux/compiler.h>
+#include <asm/lowcore.h>
+
+/*
+ * s390 uses its own implementation for per cpu data, the offset of
+ * the cpu local data area is cached in the cpu's lowcore memory.
+ * For 64 bit module code s390 forces the use of a GOT slot for the
+ * address of the per cpu variable. This is needed because the module
+ * may be more than 4G above the per cpu area.
+ */
+#if defined(__s390x__) && defined(MODULE)
+
+#define SHIFT_PERCPU_PTR(ptr,offset) (({                        \
+        extern int simple_identifier_##var(void);       \
+        unsigned long *__ptr;                           \
+        asm ( "larl %0, %1@GOTENT"              \
+            : "=a" (__ptr) : "X" (ptr) );               \
+        (typeof(ptr))((*__ptr) + (offset));     }))
+
+#else
+
+#define SHIFT_PERCPU_PTR(ptr, offset) (({                               \
+        extern int simple_identifier_##var(void);               \
+        unsigned long __ptr;                                    \
+        asm ( "" : "=a" (__ptr) : "0" (ptr) );                  \
+        (typeof(ptr)) (__ptr + (offset)); }))
+
+#endif
+
+#define __my_cpu_offset S390_lowcore.percpu_offset
+
+#include <asm-generic/percpu.h>
+
+#endif /* __ARCH_S390_PERCPU__ */