From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760783Ab1LPUyt (ORCPT ); Fri, 16 Dec 2011 15:54:49 -0500 Received: from cantor2.suse.de ([195.135.220.15]:48975 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964936Ab1LPUvt (ORCPT ); Fri, 16 Dec 2011 15:51:49 -0500 X-Mailbox-Line: From gregkh@clark.kroah.org Fri Dec 16 12:50:43 2011 Message-Id: <20111216205043.392878849@clark.kroah.org> User-Agent: quilt/0.50-24.1 Date: Fri, 16 Dec 2011 12:49:45 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, Greg KH Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, oprofile-list , Nick Piggin , Xiao Guangrong , Marcelo Tosatti , Robert Richter Subject: [12/16] export __get_user_pages_fast() function In-Reply-To: <20111216205049.GA28030@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-longterm review patch. If anyone has any objections, please let me know. ------------------ From: Xiao Guangrong commit 45888a0c6edc305495b6bd72a30e66bc40b324c6 upstream. Backport for stable kernel v2.6.32.y to v2.6.36.y. Needed for next patch: oprofile, x86: Fix nmi-unsafe callgraph support This function is used by KVM to pin process's page in the atomic context. Define the 'weak' function to avoid other architecture not support it Acked-by: Nick Piggin Signed-off-by: Xiao Guangrong Signed-off-by: Marcelo Tosatti Signed-off-by: Robert Richter Signed-off-by: Greg Kroah-Hartman --- mm/util.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) --- a/mm/util.c +++ b/mm/util.c @@ -233,6 +233,19 @@ void arch_pick_mmap_layout(struct mm_str } #endif +/* + * Like get_user_pages_fast() except its IRQ-safe in that it won't fall + * back to the regular GUP. + * If the architecture not support this fucntion, simply return with no + * page pinned + */ +int __attribute__((weak)) __get_user_pages_fast(unsigned long start, + int nr_pages, int write, struct page **pages) +{ + return 0; +} +EXPORT_SYMBOL_GPL(__get_user_pages_fast); + /** * get_user_pages_fast() - pin user pages in memory * @start: starting user address