From patchwork Tue Sep 3 15:06:32 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?q?Matthias_M=C3=A4nnich?= X-Patchwork-Id: 11128153 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BE1DB14F7 for ; Tue, 3 Sep 2019 15:07:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9AD002339D for ; Tue, 3 Sep 2019 15:07:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="PB5Ah+kY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729852AbfICPHn (ORCPT ); Tue, 3 Sep 2019 11:07:43 -0400 Received: from mail-yw1-f73.google.com ([209.85.161.73]:52362 "EHLO mail-yw1-f73.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729835AbfICPHm (ORCPT ); Tue, 3 Sep 2019 11:07:42 -0400 Received: by mail-yw1-f73.google.com with SMTP id d18so13594794ywb.19 for ; Tue, 03 Sep 2019 08:07:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=QzLwUka7MndmPbLBfBjtnVUWcO8y+yUapUjSVd2AkdE=; b=PB5Ah+kYC1m4B/Vqzh02d5Dma2M2yVL7Bdqf/cgU5C5/QHZXWWxWusz5yxJTxv/UaW cPQ+if9lMxNZfGZL8S6lAAv/KZXOdRW/TgOTyyk2SxYWVb84rGwfPhHTdzrwyml3fyYR zMB9ShCEW07O4VXQZsewgm0bwovFzEdsUHPpP51HT13xk3Eva1qhEajcX6jZ8XP0Sq9l WK3aEEJXUIn/x+ktaxUYG8u++q7nTs10fbIeFJFJgHQ61R003giZa7EC3s1heJ+v3BkU DhFAq5i9QktVcROUV7GZTvihIhoDpLPBW6QkwLuwo8b24v/88OsKzS4oZLrp9/OjXMdl ZYLw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=QzLwUka7MndmPbLBfBjtnVUWcO8y+yUapUjSVd2AkdE=; b=H2MmxACdJ0Mgpf6Yl0VnK/bpMh/a+BBORGnJCL7/8lWvmFwgVqWPyP2UojAK/OTW/o fcRWDZ2okU+WGgM5L0V0hO0KQ6nKP6on1WtXHbkEQ3SaLiIgtZ9LVQpOnYrxBi9R/Ll3 LQ65x6bg1VLhiAGXA57CttSvmibwXjtBBZuhrqWPuUYvcwuLcelaGtR0Dh+05FWPabg5 axVSC8KJ5wXx3/2TG9uHkpPayo+XNVdWBWOj1IhwVa5Qnz+Au2IjoW/iTC2gJ5XgVULl wih2mqqoIrrVywFy0R4KxMMcM2PvpSFc0Yi3MCEwtfqtJsXRy5pVUlmNW5b/VJ3iADPQ 1wTQ== X-Gm-Message-State: APjAAAXMxy8anJGZcjdi6CRGSCU46MCT/ngZjjnffnw3CAEEVMPDBDQ0 LACIzKkHJk9ThNau9jpkhyz0LpCyp9ro9g== X-Google-Smtp-Source: APXvYqwwwghshBlXbu3SzPrPSRDK2LVE5Xdl4WcySrrwEMVrzGCbbqWqp4Yfsy68npcFDyQxAHFyHkK5McSccQ== X-Received: by 2002:a81:9ac2:: with SMTP id r185mr25908588ywg.210.1567523261200; Tue, 03 Sep 2019 08:07:41 -0700 (PDT) Date: Tue, 3 Sep 2019 16:06:32 +0100 In-Reply-To: <20190903150638.242049-1-maennich@google.com> Message-Id: <20190903150638.242049-7-maennich@google.com> Mime-Version: 1.0 References: <20180716122125.175792-1-maco@android.com> <20190903150638.242049-1-maennich@google.com> X-Mailer: git-send-email 2.23.0.187.g17f5b7556c-goog Subject: [PATCH v4 06/12] export: allow definition default namespaces in Makefiles or sources From: Matthias Maennich To: linux-kernel@vger.kernel.org Cc: kernel-team@android.com, maennich@google.com, arnd@arndb.de, gregkh@linuxfoundation.org, jeyu@kernel.org, joel@joelfernandes.org, lucas.de.marchi@gmail.com, maco@android.com, sspatil@google.com, will@kernel.org, yamada.masahiro@socionext.com, linux-kbuild@vger.kernel.org, linux-modules@vger.kernel.org, linux-usb@vger.kernel.org, usb-storage@lists.one-eyed-alien.net, linux-watchdog@vger.kernel.org Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org 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 Reviewed-by: Martijn Coenen Reviewed-by: Greg Kroah-Hartman Signed-off-by: Matthias Maennich --- 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")