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=-13.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED,USER_AGENT_GIT 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 2AC09C433E2 for ; Sat, 5 Sep 2020 05:20:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EC50D208DB for ; Sat, 5 Sep 2020 05:20:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726403AbgIEFUj (ORCPT ); Sat, 5 Sep 2020 01:20:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55970 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726366AbgIEFUj (ORCPT ); Sat, 5 Sep 2020 01:20:39 -0400 Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 16B20C061244 for ; Fri, 4 Sep 2020 22:20:36 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: krisman) with ESMTPSA id C987729B717 From: Gabriel Krisman Bertazi To: viro@zeniv.linux.org.uk Cc: linux-fsdevel@vger.kernel.org, jack@suse.cz, khazhy@google.com, Gabriel Krisman Bertazi , kernel@collabora.com Subject: [PATCH v3 2/3] direct-io: don't force writeback for reads beyond EOF Date: Sat, 5 Sep 2020 01:20:22 -0400 Message-Id: <20200905052023.3719585-3-krisman@collabora.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200905052023.3719585-1-krisman@collabora.com> References: <20200905052023.3719585-1-krisman@collabora.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org If a DIO read starts past EOF, the kernel won't attempt it, so we don't need to flush dirty pages before failing the syscall. Suggested-by: Jan Kara Reviewed-by: Jan Kara Signed-off-by: Gabriel Krisman Bertazi --- fs/direct-io.c | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) diff --git a/fs/direct-io.c b/fs/direct-io.c index 6c11db1cec27..c17efe58f1c9 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -1188,19 +1188,9 @@ do_blockdev_direct_IO(struct kiocb *iocb, struct inode *inode, memset(dio, 0, offsetof(struct dio, pages)); dio->flags = flags; - if (dio->flags & DIO_LOCKING) { - if (iov_iter_rw(iter) == READ) { - struct address_space *mapping = - iocb->ki_filp->f_mapping; - - /* will be released by direct_io_worker */ - inode_lock(inode); - - retval = filemap_write_and_wait_range(mapping, offset, - end - 1); - if (retval) - goto fail_dio; - } + if (dio->flags & DIO_LOCKING && iov_iter_rw(iter) == READ) { + /* will be released by direct_io_worker */ + inode_lock(inode); } /* Once we sampled i_size check for reads beyond EOF */ @@ -1210,6 +1200,14 @@ do_blockdev_direct_IO(struct kiocb *iocb, struct inode *inode, goto fail_dio; } + if (dio->flags & DIO_LOCKING && iov_iter_rw(iter) == READ) { + struct address_space *mapping = iocb->ki_filp->f_mapping; + + retval = filemap_write_and_wait_range(mapping, offset, end - 1); + if (retval) + goto fail_dio; + } + /* * For file extending writes updating i_size before data writeouts * complete can expose uninitialized blocks in dumb filesystems. -- 2.28.0