1 files changed, 70 insertions, 0 deletions
diff --git a/include/asm-s390/percpu.h b/include/asm-s390/percpu.h
new file mode 100644
index 000000000000..123fcaca295e
--- /dev/null
+++ b/include/asm-s390/percpu.h
@@ -0,0 +1,70 @@
+#ifndef __ARCH_S390_PERCPU__
+#define __ARCH_S390_PERCPU__
+
+#include <linux/compiler.h>
+#include <asm/lowcore.h>
+
+#define __GENERIC_PER_CPU
+
+/*
+ * 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 __reloc_hide(var,offset) \
+  (*({ unsigned long *__ptr; \
+       asm ( "larl %0,per_cpu__"#var"@GOTENT" \
+             : "=a" (__ptr) : "X" (per_cpu__##var) ); \
+       (typeof(&per_cpu__##var))((*__ptr) + (offset)); }))
+
+#else
+
+#define __reloc_hide(var, offset) \
+  (*({ unsigned long __ptr; \
+       asm ( "" : "=a" (__ptr) : "0" (&per_cpu__##var) ); \
+       (typeof(&per_cpu__##var)) (__ptr + (offset)); }))
+
+#endif
+
+#ifdef CONFIG_SMP
+
+extern unsigned long __per_cpu_offset[NR_CPUS];
+
+/* Separate out the type, so (int[3], foo) works. */
+#define DEFINE_PER_CPU(type, name) \
+    __attribute__((__section__(".data.percpu"))) \
+    __typeof__(type) per_cpu__##name
+
+#define __get_cpu_var(var) __reloc_hide(var,S390_lowcore.percpu_offset)
+#define per_cpu(var,cpu) __reloc_hide(var,__per_cpu_offset[cpu])
+
+/* A macro to avoid #include hell... */
+#define percpu_modcopy(pcpudst, src, size)			\
+do {								\
+	unsigned int __i;					\
+	for (__i = 0; __i < NR_CPUS; __i++)			\
+		if (cpu_possible(__i))				\
+			memcpy((pcpudst)+__per_cpu_offset[__i],	\
+			       (src), (size));			\
+} while (0)
+
+#else /* ! SMP */
+
+#define DEFINE_PER_CPU(type, name) \
+    __typeof__(type) per_cpu__##name
+
+#define __get_cpu_var(var) __reloc_hide(var,0)
+#define per_cpu(var,cpu) __reloc_hide(var,0)
+
+#endif /* SMP */
+
+#define DECLARE_PER_CPU(type, name) extern __typeof__(type) per_cpu__##name
+
+#define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var)
+#define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var)
+
+#endif /* __ARCH_S390_PERCPU__ */