1 files changed, 26 insertions, 0 deletions

diff --git a/arch/s390/mm/maccess.c b/arch/s390/mm/maccess.c
index 81756271dc44..a8c2af8c650f 100644
--- a/arch/s390/mm/maccess.c
+++ b/arch/s390/mm/maccess.c
@@ -59,3 +59,29 @@ long probe_kernel_write(void *dst, void *src, size_t size)
         }
         return copied < 0 ? -EFAULT : 0;
 }
+
+int memcpy_real(void *dest, void *src, size_t count)
+{
+        register unsigned long _dest asm("2") = (unsigned long) dest;
+        register unsigned long _len1 asm("3") = (unsigned long) count;
+        register unsigned long _src  asm("4") = (unsigned long) src;
+        register unsigned long _len2 asm("5") = (unsigned long) count;
+        unsigned long flags;
+        int rc = -EFAULT;
+
+        if (!count)
+                return 0;
+        flags = __raw_local_irq_stnsm(0xf8UL);
+        asm volatile (
+                "0:     mvcle   %1,%2,0x0\n"
+                "1:     jo      0b\n"
+                "       lhi     %0,0x0\n"
+                "2:\n"
+                EX_TABLE(1b,2b)
+                : "+d" (rc), "+d" (_dest), "+d" (_src), "+d" (_len1),
+                  "+d" (_len2), "=m" (*((long *) dest))
+                : "m" (*((long *) src))
+                : "cc", "memory");
+        __raw_local_irq_ssm(flags);
+        return rc;
+}