2 files changed, 34 insertions, 2 deletions

diff --git a/arch/um/os-Linux/Makefile b/arch/um/os-Linux/Makefile
index d15ec2af6a22..d389c58b18b2 100644
--- a/arch/um/os-Linux/Makefile
+++ b/arch/um/os-Linux/Makefile
@@ -4,10 +4,10 @@
 #
 
 obj-y = aio.o elf_aux.o file.o mem.o process.o signal.o start_up.o time.o \
-        tt.o tty.o user_syms.o drivers/ sys-$(SUBARCH)/
+        tt.o tty.o uaccess.o user_syms.o drivers/ sys-$(SUBARCH)/
 
 USER_OBJS := aio.o elf_aux.o file.o mem.o process.o signal.o start_up.o \
-        time.o tt.o tty.o
+        time.o tt.o tty.o uaccess.o
 
 elf_aux.o: $(ARCH_DIR)/kernel-offsets.h
 CFLAGS_elf_aux.o += -I$(objtree)/arch/um
diff --git a/arch/um/os-Linux/uaccess.c b/arch/um/os-Linux/uaccess.c
new file mode 100644
index 000000000000..38d710158c3d
--- /dev/null
+++ b/arch/um/os-Linux/uaccess.c
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2001 Chris Emerson (cemerson@chiark.greenend.org.uk)
+ * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <setjmp.h>
+#include <string.h>
+
+unsigned long __do_user_copy(void *to, const void *from, int n,
+                             void **fault_addr, void **fault_catcher,
+                             void (*op)(void *to, const void *from,
+                                        int n), int *faulted_out)
+{
+        unsigned long *faddrp = (unsigned long *) fault_addr, ret;
+
+        sigjmp_buf jbuf;
+        *fault_catcher = &jbuf;
+        if(sigsetjmp(jbuf, 1) == 0){
+                (*op)(to, from, n);
+                ret = 0;
+                *faulted_out = 0;
+        }
+        else {
+                ret = *faddrp;
+                *faulted_out = 1;
+        }
+        *fault_addr = NULL;
+        *fault_catcher = NULL;
+        return ret;
+}
+