From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_NEOMUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E287FC46471 for ; Tue, 7 Aug 2018 09:14:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A04FE214DD for ; Tue, 7 Aug 2018 09:14:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A04FE214DD Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387768AbeHGL1W (ORCPT ); Tue, 7 Aug 2018 07:27:22 -0400 Received: from mx2.suse.de ([195.135.220.15]:47108 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727425AbeHGL1W (ORCPT ); Tue, 7 Aug 2018 07:27:22 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id E6E33AD3B; Tue, 7 Aug 2018 09:13:57 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id 9F7121E3BF9; Tue, 7 Aug 2018 11:13:57 +0200 (CEST) Date: Tue, 7 Aug 2018 11:13:57 +0200 From: Jan Kara To: Zhang Yi Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org, pbonzini@redhat.com, dan.j.williams@intel.com, jack@suse.cz, hch@lst.de, yu.c.zhang@intel.com, linux-mm@kvack.org, rkrcmar@redhat.com, yi.z.zhang@intel.com Subject: Re: [PATCH V2 3/4] mm: add a function to differentiate the pages is from DAX device memory Message-ID: <20180807091357.zxanrttlp3ml7mq2@quack2.suse.cz> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170912 (1.9.0) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed 11-07-18 01:03:51, Zhang Yi wrote: > DAX driver hotplug the device memory and move it to memory zone, these > pages will be marked reserved flag, however, some other kernel componet > will misconceive these pages are reserved mmio (ex: we map these dev_dax > or fs_dax pages to kvm for DIMM/NVDIMM backend). Together with the type > MEMORY_DEVICE_FS_DAX, we can use is_dax_page() to differentiate the pages > is DAX device memory or not. > > Signed-off-by: Zhang Yi > Signed-off-by: Zhang Yu The patch looks OK to me but I don't really feel too confident about this part of the kernel... But feel free to add my: Acked-by: Jan Kara Honza > --- > include/linux/mm.h | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 6e19265..9f0f690 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -856,6 +856,13 @@ static inline bool is_device_public_page(const struct page *page) > page->pgmap->type == MEMORY_DEVICE_PUBLIC; > } > > +static inline bool is_dax_page(const struct page *page) > +{ > + return is_zone_device_page(page) && > + (page->pgmap->type == MEMORY_DEVICE_FS_DAX || > + page->pgmap->type == MEMORY_DEVICE_DEV_DAX); > +} > + > #else /* CONFIG_DEV_PAGEMAP_OPS */ > static inline void dev_pagemap_get_ops(void) > { > @@ -879,6 +886,11 @@ static inline bool is_device_public_page(const struct page *page) > { > return false; > } > + > +static inline bool is_dax_page(const struct page *page) > +{ > + return false; > +} > #endif /* CONFIG_DEV_PAGEMAP_OPS */ > > static inline void get_page(struct page *page) > -- > 2.7.4 > -- Jan Kara SUSE Labs, CR