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=-6.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS 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 21E70C04AB2 for ; Fri, 10 May 2019 20:14:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E6C3D2182B for ; Fri, 10 May 2019 20:14:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=intel-com.20150623.gappssmtp.com header.i=@intel-com.20150623.gappssmtp.com header.b="yf8U/Vwd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728069AbfEJUOT (ORCPT ); Fri, 10 May 2019 16:14:19 -0400 Received: from mail-oi1-f195.google.com ([209.85.167.195]:34174 "EHLO mail-oi1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727835AbfEJUOS (ORCPT ); Fri, 10 May 2019 16:14:18 -0400 Received: by mail-oi1-f195.google.com with SMTP id v10so5455244oib.1 for ; Fri, 10 May 2019 13:14:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=intel-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=glYXor0GQ9DfKpghbnKPKxe+zUzoJeb7GoYJ26Vk6ps=; b=yf8U/VwdNl5tfgFPEKe5qh3THkRWZb9un60SOgkfJ/5LhvAwk90OALPbQmqH8NGPZg Cr23IQd+McBJGud2E9ep2+5K3niud5mH6fhTcdytKwGg0ifP80vvI1KiLl0J9xx4xwjq TEllzhY/P52SG7Zgqu0zO0TcVHYyKzcfJiA7uwMKIIPnUXohIrhjvrd+s0fzp7fbWFpQ y62fi/8hXK8LlUhb+lV4PauDhwTsmzrWQoEzPH1EBWKu2DNHNpcM/c0ugQiTxq1CS/Pn ELZfOgWViQuoOxYDdqZ2L8n4KiCZbfdn+ONJLYDNxFTBB6M7dS0ALwRsezeWWJXIVakV lNVg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=glYXor0GQ9DfKpghbnKPKxe+zUzoJeb7GoYJ26Vk6ps=; b=ojuh5QAcV0APt+uDQlvkSQs1vJ3y9P+LZm+dg4RbTnFnlrutDT5UrtLU/C7326bW27 r0XKMwwnijqbz2s0RFTEV1YROHXMP71VuciSanmdMS8YPmyLt4p+j1YIGf7OAQePcPk+ 909X0CDp2t2PuL1PfMNV1TkC01ICJgCxEWpgf5h6nisrlGKOdyUYCm4VkfiVQ1yoxDwe KHGBQ444WMqaIPa6DsOhUGbB9v82+Qia52v2nMun7B+uXV/NqxIDNppiIigkEMLPxwIe OFYgfR9VwnOGfm3v7YZhQIRfcgQSHqadSvTm9vS0eyXiYSZE4xSyo1KEBPexQN8q1uOU 9cKQ== X-Gm-Message-State: APjAAAXrbD3dCW86/ZHlh0sKATg0/KJ5ZYdqZigTii6WzkVNjgUIxqtE 53QRoh5vyMmQNUkvpoI+ojedysn9t+lsyLmTvFj7kA== X-Google-Smtp-Source: APXvYqx7Iy3DOMIV9DNLu2fGaxr7KgtVySuDwyKCLAPX5/jruFRFKJ7CbI+68cxoMCTMjkHKJ+jW3/SnCYNqZpzsnJI= X-Received: by 2002:aca:4208:: with SMTP id p8mr6821131oia.105.1557519257995; Fri, 10 May 2019 13:14:17 -0700 (PDT) MIME-Version: 1.0 References: <20190510155202.14737-1-pagupta@redhat.com> <20190510155202.14737-4-pagupta@redhat.com> In-Reply-To: <20190510155202.14737-4-pagupta@redhat.com> From: Dan Williams Date: Fri, 10 May 2019 13:14:07 -0700 Message-ID: Subject: Re: [PATCH v8 3/6] libnvdimm: add dax_dev sync flag To: Pankaj Gupta Cc: linux-nvdimm , Linux Kernel Mailing List , virtualization@lists.linux-foundation.org, KVM list , linux-fsdevel , Linux ACPI , Qemu Developers , linux-ext4 , linux-xfs , Ross Zwisler , Vishal L Verma , Dave Jiang , "Michael S. Tsirkin" , Jason Wang , Matthew Wilcox , "Rafael J. Wysocki" , Christoph Hellwig , Len Brown , Jan Kara , "Theodore Ts'o" , Andreas Dilger , "Darrick J. Wong" , lcapitulino@redhat.com, Kevin Wolf , Igor Mammedov , jmoyer , Nitesh Narayan Lal , Rik van Riel , Stefan Hajnoczi , Andrea Arcangeli , David Hildenbrand , david , cohuck@redhat.com, Xiao Guangrong , Paolo Bonzini , Adam Borowski , yuval shaia , jstaron@google.com Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 10, 2019 at 8:53 AM Pankaj Gupta wrote: > > This patch adds 'DAXDEV_SYNC' flag which is set > for nd_region doing synchronous flush. This later > is used to disable MAP_SYNC functionality for > ext4 & xfs filesystem for devices don't support > synchronous flush. > > Signed-off-by: Pankaj Gupta > --- > drivers/dax/bus.c | 2 +- > drivers/dax/super.c | 13 ++++++++++++- > drivers/md/dm.c | 3 ++- > drivers/nvdimm/pmem.c | 5 ++++- > drivers/nvdimm/region_devs.c | 7 +++++++ > include/linux/dax.h | 8 ++++++-- > include/linux/libnvdimm.h | 1 + > 7 files changed, 33 insertions(+), 6 deletions(-) [..] > diff --git a/drivers/md/dm.c b/drivers/md/dm.c > index 043f0761e4a0..ee007b75d9fd 100644 > --- a/drivers/md/dm.c > +++ b/drivers/md/dm.c > @@ -1969,7 +1969,8 @@ static struct mapped_device *alloc_dev(int minor) > sprintf(md->disk->disk_name, "dm-%d", minor); > > if (IS_ENABLED(CONFIG_DAX_DRIVER)) { > - dax_dev = alloc_dax(md, md->disk->disk_name, &dm_dax_ops); > + dax_dev = alloc_dax(md, md->disk->disk_name, &dm_dax_ops, > + DAXDEV_F_SYNC); Apologies for not realizing this until now, but this is broken. Imaging a device-mapper configuration composed of both 'async' virtio-pmem and 'sync' pmem. The 'sync' flag needs to be unified across all members. I would change this argument to '0' and then arrange for it to be set at dm_table_supports_dax() time after validating that all components support synchronous dax.