[S390] Make user-copy operations run-time configurable.

Introduces a struct uaccess_ops which allows setting user-copy
operations at run-time.

Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/kernel/s390_ksyms.c

@@ -25,12 +25,6 @@ EXPORT_SYMBOL(_oi_bitmap);
 EXPORT_SYMBOL(_ni_bitmap);
 EXPORT_SYMBOL(_zb_findmap);
 EXPORT_SYMBOL(_sb_findmap);
-EXPORT_SYMBOL(__copy_from_user_asm);
-EXPORT_SYMBOL(__copy_to_user_asm);
-EXPORT_SYMBOL(__copy_in_user_asm);
-EXPORT_SYMBOL(__clear_user_asm);
-EXPORT_SYMBOL(__strncpy_from_user_asm);
-EXPORT_SYMBOL(__strnlen_user_asm);
 EXPORT_SYMBOL(diag10);
 
 /*

arch/s390/kernel/setup.c

@@ -50,6 +50,12 @@
 #include <asm/ptrace.h>
 #include <asm/sections.h>
 
+/*
+ * User copy operations.
+ */
+struct uaccess_ops uaccess;
+EXPORT_SYMBOL_GPL(uaccess);
+
 /*
  * Machine setup..
  */
@@ -641,6 +647,7 @@ setup_arch(char **cmdline_p)
 
 	memory_end = memory_size;
 
+	memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
 	parse_early_param();
 
 #ifndef CONFIG_64BIT

arch/s390/lib/Makefile

@@ -4,6 +4,5 @@
 
 EXTRA_AFLAGS := -traditional
 
-lib-y += delay.o string.o
-lib-y += $(if $(CONFIG_64BIT),uaccess64.o,uaccess.o)
+lib-y += delay.o string.o uaccess_std.o
 lib-$(CONFIG_SMP) += spinlock.o