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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 59896C67863 for ; Mon, 22 Oct 2018 20:18:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C228820665 for ; Mon, 22 Oct 2018 20:18:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C228820665 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com 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 S1728907AbeJWEim (ORCPT ); Tue, 23 Oct 2018 00:38:42 -0400 Received: from mga05.intel.com ([192.55.52.43]:13946 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725788AbeJWEik (ORCPT ); Tue, 23 Oct 2018 00:38:40 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 22 Oct 2018 13:18:42 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,413,1534834800"; d="scan'208";a="80737009" Received: from viggo.jf.intel.com (HELO localhost.localdomain) ([10.54.77.144]) by fmsmga008.fm.intel.com with ESMTP; 22 Oct 2018 13:18:41 -0700 Subject: [PATCH 4/9] dax/kmem: allow PMEM devices to bind to KMEM driver To: linux-kernel@vger.kernel.org Cc: Dave Hansen , dan.j.williams@intel.com, dave.jiang@intel.com, zwisler@kernel.org, vishal.l.verma@intel.com, thomas.lendacky@amd.com, akpm@linux-foundation.org, mhocko@suse.com, linux-nvdimm@lists.01.org, linux-mm@kvack.org, ying.huang@intel.com, fengguang.wu@intel.com From: Dave Hansen Date: Mon, 22 Oct 2018 13:13:24 -0700 References: <20181022201317.8558C1D8@viggo.jf.intel.com> In-Reply-To: <20181022201317.8558C1D8@viggo.jf.intel.com> Message-Id: <20181022201324.EBB64302@viggo.jf.intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently, a persistent memory device's mode must be coordinated with the driver to which it needs to bind. To change it from the fsdax to the device-dax driver, you first change the mode of the device itself. Instead of adding a new device mode, allow the PMEM mode to also bind to the KMEM driver. As I write this, I'm realizing that it might have just been better to add a new device mode, rather than hijacking the PMEM eode. If this is the case, please speak up, NVDIMM folks. :) Cc: Dan Williams Cc: Dave Jiang Cc: Ross Zwisler Cc: Vishal Verma Cc: Tom Lendacky Cc: Andrew Morton Cc: Michal Hocko Cc: linux-nvdimm@lists.01.org Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org Cc: Huang Ying Cc: Fengguang Wu --- b/drivers/nvdimm/bus.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff -puN drivers/nvdimm/bus.c~dax-kmem-try-again-2018-3-bus-match-override drivers/nvdimm/bus.c --- a/drivers/nvdimm/bus.c~dax-kmem-try-again-2018-3-bus-match-override 2018-10-22 13:12:22.522930391 -0700 +++ b/drivers/nvdimm/bus.c 2018-10-22 13:12:22.525930391 -0700 @@ -464,11 +464,24 @@ static struct nd_device_driver nd_bus_dr static int nvdimm_bus_match(struct device *dev, struct device_driver *drv) { struct nd_device_driver *nd_drv = to_nd_device_driver(drv); + bool match; if (is_nvdimm_bus(dev) && nd_drv == &nd_bus_driver) return true; - return !!test_bit(to_nd_device_type(dev), &nd_drv->type); + match = !!test_bit(to_nd_device_type(dev), &nd_drv->type); + + /* + * We allow PMEM devices to be bound to the KMEM driver. + * Force a match if we detect a PMEM device type but + * a KMEM device driver. + */ + if (!match && + (to_nd_device_type(dev) == ND_DEVICE_DAX_PMEM) && + (nd_drv->type == ND_DRIVER_DAX_KMEM)) + match = true; + + return match; } static ASYNC_DOMAIN_EXCLUSIVE(nd_async_domain); _