To avoid excessive usage of EXPORT_SYMBOL_NS(sym, MY_NAMESPACE), where MY_NAMESPACE will always be the namespace we are exporting to, allow exporting all definitions of EXPORT_SYMBOL() and friends by defining DEFAULT_SYMBOL_NAMESPACE.
For example, to export all symbols defined in usb-common into the namespace USB_COMMON, add a line like this to drivers/usb/common/Makefile: ccflags-y += -DDEFAULT_SYMBOL_NAMESPACE=USB_COMMON That is equivalent to changing all EXPORT_SYMBOL(sym) definitions to EXPORT_SYMBOL_NS(sym, USB_COMMON). Subsequently all symbol namespaces functionality will apply. Another way of making use of this feature is to define the namespace within source or header files similar to how TRACE_SYSTEM defines are used: #undef DEFAULT_SYMBOL_NAMESPACE #define DEFAULT_SYMBOL_NAMESPACE USB_COMMON Please note that, as opposed to TRACE_SYSTEM, DEFAULT_SYMBOL_NAMESPACE has to be defined before including include/linux/export.h. If DEFAULT_SYMBOL_NAMESPACE is defined, a symbol can still be exported to another namespace by using EXPORT_SYMBOL_NS() and friends with explicitly specifying the namespace. Suggested-by: Arnd Bergmann <a...@arndb.de> Reviewed-by: Martijn Coenen <m...@android.com> Reviewed-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> Signed-off-by: Matthias Maennich <maenn...@google.com> --- include/linux/export.h | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/include/linux/export.h b/include/linux/export.h index d59461e71478..2c5468d8ea9a 100644 --- a/include/linux/export.h +++ b/include/linux/export.h @@ -166,6 +166,12 @@ struct kernel_symbol { #define __EXPORT_SYMBOL ___EXPORT_SYMBOL #endif +#ifdef DEFAULT_SYMBOL_NAMESPACE +#undef __EXPORT_SYMBOL +#define __EXPORT_SYMBOL(sym, sec) \ + __EXPORT_SYMBOL_NS(sym, sec, DEFAULT_SYMBOL_NAMESPACE) +#endif + #define EXPORT_SYMBOL(sym) __EXPORT_SYMBOL(sym, "") #define EXPORT_SYMBOL_GPL(sym) __EXPORT_SYMBOL(sym, "_gpl") #define EXPORT_SYMBOL_GPL_FUTURE(sym) __EXPORT_SYMBOL(sym, "_gpl_future") -- 2.23.0.187.g17f5b7556c-goog