From patchwork Wed Apr 24 17:18:03 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andreas Gruenbacher X-Patchwork-Id: 10915459 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4DEB513B5 for ; Wed, 24 Apr 2019 18:06:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 40BC228A30 for ; Wed, 24 Apr 2019 18:06:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 343C728AC1; Wed, 24 Apr 2019 18:06:03 +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=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, 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 E18C828A30 for ; Wed, 24 Apr 2019 18:06:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389365AbfDXSF4 (ORCPT ); Wed, 24 Apr 2019 14:05:56 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34170 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388795AbfDXRSM (ORCPT ); Wed, 24 Apr 2019 13:18:12 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 1C0093147DD8; Wed, 24 Apr 2019 17:18:12 +0000 (UTC) Received: from max.home.com (unknown [10.40.205.80]) by smtp.corp.redhat.com (Postfix) with ESMTP id 164305C21E; Wed, 24 Apr 2019 17:18:06 +0000 (UTC) From: Andreas Gruenbacher To: cluster-devel@redhat.com, Christoph Hellwig Cc: Bob Peterson , Jan Kara , Dave Chinner , Ross Lagerwall , Mark Syms , =?utf-8?b?RWR3aW4gVMO2csO2aw==?= , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Andreas Gruenbacher Subject: [PATCH 1/2] iomap: Add a page_prepare callback Date: Wed, 24 Apr 2019 19:18:03 +0200 Message-Id: <20190424171804.4305-1-agruenba@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.49]); Wed, 24 Apr 2019 17:18:12 +0000 (UTC) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add a page_prepare calback that's called before a page is written to. This will be used by gfs2 to start a transaction in page_prepare and end it in page_done. Other filesystems that implement data journaling will require the same kind of mechanism. Signed-off-by: Andreas Gruenbacher --- fs/iomap.c | 4 ++++ include/linux/iomap.h | 9 ++++++--- 2 files changed, 10 insertions(+), 3 deletions(-) diff --git a/fs/iomap.c b/fs/iomap.c index 97cb9d486a7d..abd9aa76dbd1 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -684,6 +684,10 @@ iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, unsigned flags, status = __block_write_begin_int(page, pos, len, NULL, iomap); else status = __iomap_write_begin(inode, pos, len, page, iomap); + + if (likely(!status) && iomap->page_prepare) + status = iomap->page_prepare(inode, pos, len, page, iomap); + if (unlikely(status)) { unlock_page(page); put_page(page); diff --git a/include/linux/iomap.h b/include/linux/iomap.h index 0fefb5455bda..0982f3e13e56 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -65,10 +65,13 @@ struct iomap { void *private; /* filesystem private */ /* - * Called when finished processing a page in the mapping returned in - * this iomap. At least for now this is only supported in the buffered - * write path. + * Called before / after processing a page in the mapping returned in + * this iomap. At least for now, this is only supported in the + * buffered write path. When page_prepare returns 0 for a page, + * page_done is called for that page as well. */ + int (*page_prepare)(struct inode *inode, loff_t pos, unsigned len, + struct page *page, struct iomap *iomap); void (*page_done)(struct inode *inode, loff_t pos, unsigned copied, struct page *page, struct iomap *iomap); };