parisc: add strict copy size checks (v2)

Add CONFIG_DEBUG_STRICT_USER_COPY_CHECKS, copied from the x86
implementation. Tested with 32 and 64bit kernel.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
diff --git a/arch/parisc/lib/memcpy.c b/arch/parisc/lib/memcpy.c
index abf41f4..1dbca5c 100644
--- a/arch/parisc/lib/memcpy.c
+++ b/arch/parisc/lib/memcpy.c
@@ -475,7 +475,8 @@
 	return pa_memcpy((void __force *)dst, src, len);
 }
 
-unsigned long copy_from_user(void *dst, const void __user *src, unsigned long len)
+EXPORT_SYMBOL(__copy_from_user);
+unsigned long __copy_from_user(void *dst, const void __user *src, unsigned long len)
 {
 	mtsp(get_user_space(), 1);
 	mtsp(get_kernel_space(), 2);