From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756737Ab2BGJsx (ORCPT ); Tue, 7 Feb 2012 04:48:53 -0500 Received: from mailout3.w1.samsung.com ([210.118.77.13]:44971 "EHLO mailout3.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756187Ab2BGJsv (ORCPT ); Tue, 7 Feb 2012 04:48:51 -0500 MIME-version: 1.0 Content-transfer-encoding: 7BIT Content-type: text/plain; charset=us-ascii Date: Tue, 07 Feb 2012 10:48:48 +0100 From: Marek Szyprowski Subject: RE: Contiguous Memory Allocator on HIGHMEM In-reply-to: <4F30E97F.9000409@ingenic.cn> To: "'cp.zou'" Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, "'Michal Nazarewicz'" , "'Kyungmin Park'" , "'Andrew Morton'" , "'Mel Gorman'" Message-id: <003601cce57d$b0df2af0$129d80d0$%szyprowski@samsung.com> Organization: SPRC X-Mailer: Microsoft Office Outlook 12.0 Content-language: pl Thread-index: Aczld7zmvUQGSkPWQXqtF/jnlo+JqwABGn5A References: <1328271538-14502-1-git-send-email-m.szyprowski@samsung.com> <4F30E97F.9000409@ingenic.cn> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Tuesday, February 07, 2012 10:06 AM cp.zou wrote: > Hello everyone! > > I'm recently learning CMA, and I want to implement support for > contiguous memory areas placed in HIGHMEM zone,do you have any suggestions? CMA memory management core (migration and allocation of pages) should support areas placed in HIGHMEM without any additional works. The main limitation is in the DMA-mapping framework. Right now it makes certain assumptions about page mappings to simplify allocation process. You need to add support for dynamic mappings there. Best regards -- Marek Szyprowski Samsung Poland R&D Center