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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 6097DC282CE for ; Wed, 10 Apr 2019 04:10:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3ACF9217D6 for ; Wed, 10 Apr 2019 04:10:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727178AbfDJEK3 (ORCPT ); Wed, 10 Apr 2019 00:10:29 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60504 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725924AbfDJEK3 (ORCPT ); Wed, 10 Apr 2019 00:10:29 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id DEBA688AAD; Wed, 10 Apr 2019 04:10:28 +0000 (UTC) Received: from dhcp201-121.englab.pnq.redhat.com (dhcp-10-65-161-59.pnq.redhat.com [10.65.161.59]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4489B6013A; Wed, 10 Apr 2019 04:10:03 +0000 (UTC) From: Pankaj Gupta To: linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-acpi@vger.kernel.org, qemu-devel@nongnu.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org Cc: dan.j.williams@intel.com, zwisler@kernel.org, vishal.l.verma@intel.com, dave.jiang@intel.com, mst@redhat.com, jasowang@redhat.com, willy@infradead.org, rjw@rjwysocki.net, hch@infradead.org, lenb@kernel.org, jack@suse.cz, tytso@mit.edu, adilger.kernel@dilger.ca, darrick.wong@oracle.com, lcapitulino@redhat.com, kwolf@redhat.com, imammedo@redhat.com, jmoyer@redhat.com, nilal@redhat.com, riel@surriel.com, stefanha@redhat.com, aarcange@redhat.com, david@redhat.com, david@fromorbit.com, cohuck@redhat.com, xiaoguangrong.eric@gmail.com, pbonzini@redhat.com, kilobyte@angband.pl, yuval.shaia@oracle.com, pagupta@redhat.com Subject: [PATCH v5 4/6] dax: check synchronous mapping is supported Date: Wed, 10 Apr 2019 09:38:24 +0530 Message-Id: <20190410040826.24371-5-pagupta@redhat.com> In-Reply-To: <20190410040826.24371-1-pagupta@redhat.com> References: <20190410040826.24371-1-pagupta@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Wed, 10 Apr 2019 04:10:29 +0000 (UTC) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org This patch introduces 'daxdev_mapping_supported' helper which checks if 'MAP_SYNC' is supported with filesystem mapping. It also checks if corresponding dax_device is synchronous. Virtio pmem device is asynchronous and does not not support VM_SYNC. Suggested-by: Jan Kara Signed-off-by: Pankaj Gupta --- include/linux/dax.h | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/include/linux/dax.h b/include/linux/dax.h index b896706a5ee9..4a2a60ffec86 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -38,6 +38,24 @@ void kill_dax(struct dax_device *dax_dev); void dax_write_cache(struct dax_device *dax_dev, bool wc); bool dax_write_cache_enabled(struct dax_device *dax_dev); bool dax_synchronous(struct dax_device *dax_dev); + +/* + * Callers check if synchronous mapping is enabled for DAX file + * and attached dax device is also synchronous. + * + * dax_synchronous function verifies if dax device is synchronous. + * Currently, only virtio pmem device supports asynchronous device + * flush. + */ +static inline bool daxdev_mapping_supported(struct vm_area_struct *vma, + struct dax_device *dax_dev) +{ + if (!(vma->vm_flags & VM_SYNC)) + return true; + if (!IS_DAX(file_inode(vma->vm_file))) + return false; + return dax_synchronous(dax_dev); +} #else static inline struct dax_device *dax_get_by_host(const char *host) { @@ -69,6 +87,11 @@ static inline bool dax_synchronous(struct dax_device *dax_dev) { return true; } +static inline bool daxdev_mapping_supported(struct vm_area_struct *vma, + struct dax_device *dax_dev) +{ + return true; +} #endif struct writeback_control; -- 2.20.1