From patchwork Wed Oct 10 00:11:27 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Darrick J. Wong" X-Patchwork-Id: 10633499 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 0B85916B1 for ; Wed, 10 Oct 2018 00:11:43 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F393B29CCC for ; Wed, 10 Oct 2018 00:11:42 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id F172829CD0; Wed, 10 Oct 2018 00:11:42 +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=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, UNPARSEABLE_RELAY 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 A523029C74 for ; Wed, 10 Oct 2018 00:11:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726867AbeJJHbH (ORCPT ); Wed, 10 Oct 2018 03:31:07 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:51334 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725800AbeJJHbG (ORCPT ); Wed, 10 Oct 2018 03:31:06 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w9A08pp2119795; Wed, 10 Oct 2018 00:11:35 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : from : to : cc : date : message-id : in-reply-to : references : mime-version : content-type : content-transfer-encoding; s=corp-2018-07-02; bh=wh5HxGg/bRAL9efUSGh+2qdh0v0M5Mja7JnBFsFMIMQ=; b=tvvi/USrB+UZhF1IqRPQW03XnX5YXlupLYSoDIJmEVbQW50dZu/gkDL9pBzj3hKmXzI3 NjnJ0sAQyVqELWbjSH5H48gNDd4qRyTHYnMqFwJ2H1fXwBltN5194xWACxT964HxDZUC /4B1SAp2SNTtyo1YpO0QoWSPeCLr/Xb8UFKa3faLJ8mV5Zkf8lVtCZudD8GoM0BYD2SZ 8a1d+L9LcR2WPFYnEKHli6oBxEQUxsBYxG9ABemqtIMD9lnqLuKLWbF63pc7HWyR9HDx YvDr3MqnNMsg6YLDQIr/qYCcmToZC/zj63xiD/lGBRuCFnjHA2JnBKy8T/NOHT3k1OER yQ== Received: from userv0022.oracle.com (userv0022.oracle.com [156.151.31.74]) by userp2130.oracle.com with ESMTP id 2mxmftrvgh-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 10 Oct 2018 00:11:35 +0000 Received: from aserv0122.oracle.com (aserv0122.oracle.com [141.146.126.236]) by userv0022.oracle.com (8.14.4/8.14.4) with ESMTP id w9A0BYIO009889 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 10 Oct 2018 00:11:34 GMT Received: from abhmp0015.oracle.com (abhmp0015.oracle.com [141.146.116.21]) by aserv0122.oracle.com (8.14.4/8.14.4) with ESMTP id w9A0BXDK003326; Wed, 10 Oct 2018 00:11:33 GMT Received: from localhost (/10.159.249.114) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 10 Oct 2018 00:11:33 +0000 Subject: [PATCH 07/25] vfs: skip zero-length dedupe requests From: "Darrick J. Wong" To: david@fromorbit.com, darrick.wong@oracle.com Cc: sandeen@redhat.com, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-unionfs@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, Christoph Hellwig , ocfs2-devel@oss.oracle.com Date: Tue, 09 Oct 2018 17:11:27 -0700 Message-ID: <153913028716.32295.15849395030883190383.stgit@magnolia> In-Reply-To: <153913023835.32295.13962696655740190941.stgit@magnolia> References: <153913023835.32295.13962696655740190941.stgit@magnolia> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9041 signatures=668706 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=725 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1810100000 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Darrick J. Wong Don't bother calling the filesystem for a zero-length dedupe request; we can return zero and exit. Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig --- fs/read_write.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/read_write.c b/fs/read_write.c index f7b728d4972f..3ff90b3315fb 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1975,6 +1975,11 @@ int vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos, if (!dst_file->f_op->dedupe_file_range) goto out_drop_write; + if (len == 0) { + ret = 0; + goto out_drop_write; + } + ret = dst_file->f_op->dedupe_file_range(src_file, src_pos, dst_file, dst_pos, len); out_drop_write: