From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965102AbbLOP7j (ORCPT ); Tue, 15 Dec 2015 10:59:39 -0500 Received: from swsoft-msk-nat.sw.ru ([195.214.232.10]:50001 "EHLO sandbox" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S964985AbbLOP7i (ORCPT ); Tue, 15 Dec 2015 10:59:38 -0500 Subject: [PATCH] fcntl: allow to set O_DIRECT flag on pipe From: Stanislav Kinsburskiy To: bfields@fieldses.org, jlayton@poochiereds.net, viro@zeniv.linux.org.uk Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, devel@criu.org Date: Tue, 15 Dec 2015 19:14:04 +0400 Message-ID: <20151215151325.15499.65499.stgit@localhost.localdomain> User-Agent: StGit/0.17-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org With packetized mode for pipes, it's not possible to set O_DIRECT on pipe file via sys_fcntl, because of unsupported (by pipes) sanity checks. Ability to set this flag will be used by CRIU to migrate packetized pipes. Signed-off-by: Stanislav Kinsburskiy --- fs/fcntl.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/fcntl.c b/fs/fcntl.c index ee85cd4..4463a87 100644 --- a/fs/fcntl.c +++ b/fs/fcntl.c @@ -51,7 +51,8 @@ static int setfl(int fd, struct file * filp, unsigned long arg) if (arg & O_NDELAY) arg |= O_NONBLOCK; - if (arg & O_DIRECT) { + /* Pipe packetized mode is controlled by O_DIRECT flag */ + if (!IS_FIFO(f->f_mode) && (arg & O_DIRECT)) { if (!filp->f_mapping || !filp->f_mapping->a_ops || !filp->f_mapping->a_ops->direct_IO) return -EINVAL;