From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761432AbXFTSgw (ORCPT ); Wed, 20 Jun 2007 14:36:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759327AbXFTSbB (ORCPT ); Wed, 20 Jun 2007 14:31:01 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:46759 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757087AbXFTSaN (ORCPT ); Wed, 20 Jun 2007 14:30:13 -0400 Message-Id: <20070620183011.571596436@sgi.com> References: <20070620182907.506775016@sgi.com> User-Agent: quilt/0.46-1 Date: Wed, 20 Jun 2007 11:29:31 -0700 From: clameter@sgi.com To: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Christoph Hellwig , Mel Gorman Cc: William Lee Irwin III , David Chinner Cc: Jens Axboe , Badari Pulavarty Cc: Maxim Levitsky Subject: [24/37] compound pages: Add new support functions Content-Disposition: inline; filename=compound_functions Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org compound_pages(page) -> Determines base pages of a compound page compound_shift(page) -> Determine the page shift of a compound page compound_size(page) -> Determine the size of a compound page Signed-off-by: Christoph Lameter --- include/linux/mm.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) Index: vps/include/linux/mm.h =================================================================== --- vps.orig/include/linux/mm.h 2007-06-11 15:56:37.000000000 -0700 +++ vps/include/linux/mm.h 2007-06-12 19:06:28.000000000 -0700 @@ -365,6 +365,21 @@ static inline void set_compound_order(st page[1].lru.prev = (void *)order; } +static inline int compound_pages(struct page *page) +{ + return 1 << compound_order(page); +} + +static inline int compound_shift(struct page *page) +{ + return PAGE_SHIFT + compound_order(page); +} + +static inline int compound_size(struct page *page) +{ + return PAGE_SIZE << compound_order(page); +} + /* * Multiple processes may "see" the same page. E.g. for untouched * mappings of /dev/null, all processes see the same page full of --