From patchwork Mon Jun 12 12:23:06 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Layton X-Patchwork-Id: 9780961 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 6A19660244 for ; Mon, 12 Jun 2017 12:25:54 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5151626E49 for ; Mon, 12 Jun 2017 12:25:54 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 464F328438; Mon, 12 Jun 2017 12:25:54 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 06ACD26E49 for ; Mon, 12 Jun 2017 12:25:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752663AbdFLMZu (ORCPT ); Mon, 12 Jun 2017 08:25:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58594 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752228AbdFLMXi (ORCPT ); Mon, 12 Jun 2017 08:23:38 -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 66B8E80F97; Mon, 12 Jun 2017 12:23:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 66B8E80F97 Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=jlayton@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 66B8E80F97 Received: from tleilax.poochiereds.net (ovpn-120-91.rdu2.redhat.com [10.10.120.91]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2416A5C6D5; Mon, 12 Jun 2017 12:23:37 +0000 (UTC) From: Jeff Layton To: Andrew Morton , Al Viro , Jan Kara , tytso@mit.edu, axboe@kernel.dk, mawilcox@microsoft.com, ross.zwisler@linux.intel.com, corbet@lwn.net, Chris Mason , Josef Bacik , David Sterba , "Darrick J . Wong" Cc: linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-block@vger.kernel.org Subject: [PATCH v6 12/20] fs: add a new fstype flag to indicate how writeback errors are tracked Date: Mon, 12 Jun 2017 08:23:06 -0400 Message-Id: <20170612122316.13244-15-jlayton@redhat.com> In-Reply-To: <20170612122316.13244-1-jlayton@redhat.com> References: <20170612122316.13244-1-jlayton@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 [10.5.110.27]); Mon, 12 Jun 2017 12:23:38 +0000 (UTC) Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Now that we have new infrastructure for handling writeback errors using errseq_t, we need to convert the existing code to use it. We could attempt to retrofit the old interfaces on top of the new, but there is a conceptual disconnect here in the case of internal callers that invoke filemap_fdatawait and the like. When reporting writeback errors, we will always report errors that have occurred since a particular point in time. With the old writeback error reporting, the time we used was "since it was last tested/cleared" which is entirely arbitrary and potentially racy. Now, we can report the latest error that has occurred since an arbitrary point in time (represented as a sampled errseq_t value). This means that we need to touch each filesystem that calls filemap_check_errors in some fashion and ensure that we establish sane "since" values for those callers. But...some code is shared between filesystems and needs to be able to handle both error tracking schemes. Add a new FS_WB_ERRSEQ flag to the fstype. Later patches will set and key off of that to decide what behavior should be used. Signed-off-by: Jeff Layton --- include/linux/fs.h | 1 + 1 file changed, 1 insertion(+) diff --git a/include/linux/fs.h b/include/linux/fs.h index 6cd87887430b..17ba6284ab14 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2023,6 +2023,7 @@ struct file_system_type { #define FS_BINARY_MOUNTDATA 2 #define FS_HAS_SUBTYPE 4 #define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */ +#define FS_WB_ERRSEQ 16 /* errseq_t writeback err tracking */ #define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */ struct dentry *(*mount) (struct file_system_type *, int, const char *, void *);