From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755256Ab2GJANM (ORCPT ); Mon, 9 Jul 2012 20:13:12 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:34782 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755239Ab2GJANI (ORCPT ); Mon, 9 Jul 2012 20:13:08 -0400 From: Anton Vorontsov To: Greg Kroah-Hartman , Kees Cook , Colin Cross , Tony Luck , Steven Rostedt , Frederic Weisbecker , Ingo Molnar Cc: Arnd Bergmann , John Stultz , Shuah Khan , arve@android.com, Rebecca Schultz Zavin , Jesper Juhl , Randy Dunlap , Stephen Boyd , Thomas Meyer , Andrew Morton , Marco Stornelli , WANG Cong , linux-kernel@vger.kernel.org, devel@driverdev.osuosl.org, linaro-kernel@lists.linaro.org, patches@linaro.org, kernel-team@android.com Subject: [PATCH 2/8] pstore: Introduce write_buf backend callback Date: Mon, 9 Jul 2012 17:10:40 -0700 Message-Id: <1341879046-5197-2-git-send-email-anton.vorontsov@linaro.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <20120710001004.GA22744@lizard> References: <20120710001004.GA22744@lizard> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org For function tracing we need to stop using pstore.buf directly, since in a tracing callback we can't use spinlocks, and thus we can't safely use the global buffer. With write_buf callback, backends no longer need to access pstore.buf directly, and thus we can pass any buffers (e.g. allocated on stack). Signed-off-by: Anton Vorontsov --- fs/pstore/platform.c | 10 ++++++++++ include/linux/pstore.h | 4 ++++ 2 files changed, 14 insertions(+) diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index 6b3ff04..ef5ca8a 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -188,6 +188,14 @@ static void pstore_register_console(void) static void pstore_register_console(void) {} #endif +static int pstore_write_compat(enum pstore_type_id type, + enum kmsg_dump_reason reason, + u64 *id, unsigned int part, + size_t size, struct pstore_info *psi) +{ + return psi->write_buf(type, reason, id, part, psinfo->buf, size, psi); +} + /* * platform specific persistent storage driver registers with * us here. If pstore is already mounted, call the platform @@ -212,6 +220,8 @@ int pstore_register(struct pstore_info *psi) return -EINVAL; } + if (!psi->write) + psi->write = pstore_write_compat; psinfo = psi; mutex_init(&psinfo->read_mutex); spin_unlock(&pstore_lock); diff --git a/include/linux/pstore.h b/include/linux/pstore.h index 1bd014b..b107484 100644 --- a/include/linux/pstore.h +++ b/include/linux/pstore.h @@ -48,6 +48,10 @@ struct pstore_info { int (*write)(enum pstore_type_id type, enum kmsg_dump_reason reason, u64 *id, unsigned int part, size_t size, struct pstore_info *psi); + int (*write_buf)(enum pstore_type_id type, + enum kmsg_dump_reason reason, u64 *id, + unsigned int part, const char *buf, size_t size, + struct pstore_info *psi); int (*erase)(enum pstore_type_id type, u64 id, struct pstore_info *psi); void *data; -- 1.7.10.4