From patchwork Tue Jun 6 20:45:21 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Coddington X-Patchwork-Id: 9769963 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 85B7660364 for ; Tue, 6 Jun 2017 20:46:07 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 718C42623C for ; Tue, 6 Jun 2017 20:46:07 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 66944262F2; Tue, 6 Jun 2017 20:46:07 +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 779362623C for ; Tue, 6 Jun 2017 20:46:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751527AbdFFUp0 (ORCPT ); Tue, 6 Jun 2017 16:45:26 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34400 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751445AbdFFUpZ (ORCPT ); Tue, 6 Jun 2017 16:45:25 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 6AFA0C04B311; Tue, 6 Jun 2017 20:45:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 6AFA0C04B311 Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=bcodding@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 6AFA0C04B311 Received: from bcodding.csb (ovpn-66-130.rdu2.redhat.com [10.10.67.130] (may be forged)) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v56KjN63002322; Tue, 6 Jun 2017 16:45:23 -0400 Received: by bcodding.csb (Postfix, from userid 24008) id 1D20310C3110; Tue, 6 Jun 2017 16:45:23 -0400 (EDT) From: Benjamin Coddington To: Jeff Layton , bfields@fieldses.org, Alexander Viro Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/3] fs/locks: Use allocation rather than the stack in fcntl_getlk() Date: Tue, 6 Jun 2017 16:45:21 -0400 Message-Id: In-Reply-To: References: In-Reply-To: References: X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Tue, 06 Jun 2017 20:45:24 +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 Struct file_lock is fairly large, so let's save some space on the stack by using an allocation for struct file_lock in fcntl_getlk(), just as we do for fcntl_setlk(). Signed-off-by: Benjamin Coddington --- fs/locks.c | 46 ++++++++++++++++++++++++++-------------------- 1 file changed, 26 insertions(+), 20 deletions(-) diff --git a/fs/locks.c b/fs/locks.c index afefeb4ad6de..d7daa6c8932f 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -2086,14 +2086,17 @@ static void posix_lock_to_flock64(struct flock64 *flock, struct file_lock *fl) */ int fcntl_getlk(struct file *filp, unsigned int cmd, struct flock *flock) { - struct file_lock file_lock; + struct file_lock *fl; int error; + fl = locks_alloc_lock(); + if (fl == NULL) + return -ENOMEM; error = -EINVAL; if (flock->l_type != F_RDLCK && flock->l_type != F_WRLCK) goto out; - error = flock_to_posix_lock(filp, &file_lock, flock); + error = flock_to_posix_lock(filp, fl, flock); if (error) goto out; @@ -2103,23 +2106,22 @@ int fcntl_getlk(struct file *filp, unsigned int cmd, struct flock *flock) goto out; cmd = F_GETLK; - file_lock.fl_flags |= FL_OFDLCK; - file_lock.fl_owner = filp; + fl->fl_flags |= FL_OFDLCK; + fl->fl_owner = filp; } - error = vfs_test_lock(filp, &file_lock); + error = vfs_test_lock(filp, fl); if (error) goto out; - flock->l_type = file_lock.fl_type; - if (file_lock.fl_type != F_UNLCK) { - error = posix_lock_to_flock(flock, &file_lock); + flock->l_type = fl->fl_type; + if (fl->fl_type != F_UNLCK) { + error = posix_lock_to_flock(flock, fl); if (error) - goto rel_priv; + goto out; } -rel_priv: - locks_release_private(&file_lock); out: + locks_free_lock(fl); return error; } @@ -2298,14 +2300,18 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd, */ int fcntl_getlk64(struct file *filp, unsigned int cmd, struct flock64 *flock) { - struct file_lock file_lock; + struct file_lock *fl; int error; + fl = locks_alloc_lock(); + if (fl == NULL) + return -ENOMEM; + error = -EINVAL; if (flock->l_type != F_RDLCK && flock->l_type != F_WRLCK) goto out; - error = flock64_to_posix_lock(filp, &file_lock, flock); + error = flock64_to_posix_lock(filp, fl, flock); if (error) goto out; @@ -2315,20 +2321,20 @@ int fcntl_getlk64(struct file *filp, unsigned int cmd, struct flock64 *flock) goto out; cmd = F_GETLK64; - file_lock.fl_flags |= FL_OFDLCK; - file_lock.fl_owner = filp; + fl->fl_flags |= FL_OFDLCK; + fl->fl_owner = filp; } - error = vfs_test_lock(filp, &file_lock); + error = vfs_test_lock(filp, fl); if (error) goto out; - flock->l_type = file_lock.fl_type; - if (file_lock.fl_type != F_UNLCK) - posix_lock_to_flock64(flock, &file_lock); + flock->l_type = fl->fl_type; + if (fl->fl_type != F_UNLCK) + posix_lock_to_flock64(flock, fl); - locks_release_private(&file_lock); out: + locks_free_lock(fl); return error; }