From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932198AbWAYWkm (ORCPT ); Wed, 25 Jan 2006 17:40:42 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932193AbWAYWk1 (ORCPT ); Wed, 25 Jan 2006 17:40:27 -0500 Received: from ogre.sisk.pl ([217.79.144.158]:35535 "EHLO ogre.sisk.pl") by vger.kernel.org with ESMTP id S932197AbWAYWk0 (ORCPT ); Wed, 25 Jan 2006 17:40:26 -0500 From: "Rafael J. Wysocki" To: Andrew Morton Subject: [PATCH -mm] swsusp: userland interface fixes Date: Wed, 25 Jan 2006 23:41:36 +0100 User-Agent: KMail/1.9 Cc: Pavel Machek , LKML MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-2" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200601252341.37361.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, This patch contains some minor fixes of the swsusp userland interface: 1) use atomic_add_unless() instead of atomic_dec_and_test()/atomic_inc(), 2) remove a (unnecessary) memory barrier, 3) drop (unnecessary) access_ok() (actually the page will get released when the device is closed, so we don't need to worry if put_user() fails). Please consider for applying. Greetings, Rafael Signed-off-by: Rafael J. Wysocki kernel/power/user.c | 11 ++--------- 1 files changed, 2 insertions(+), 9 deletions(-) Index: linux-2.6.16-rc1-mm3/kernel/power/user.c =================================================================== --- linux-2.6.16-rc1-mm3.orig/kernel/power/user.c 2006-01-25 21:21:13.000000000 +0100 +++ linux-2.6.16-rc1-mm3/kernel/power/user.c 2006-01-25 21:53:52.000000000 +0100 @@ -40,10 +40,8 @@ static int snapshot_open(struct inode *i { struct snapshot_data *data; - if (!atomic_dec_and_test(&device_available)) { - atomic_inc(&device_available); + if (!atomic_add_unless(&device_available, -1, 0)) return -EBUSY; - } if ((filp->f_flags & O_ACCMODE) == O_RDWR) return -ENOSYS; @@ -198,7 +196,6 @@ static int snapshot_ioctl(struct inode * pm_prepare_console(); error = device_suspend(PMSG_FREEZE); if (!error) { - mb(); error = swsusp_resume(); device_resume(); } @@ -223,10 +220,6 @@ static int snapshot_ioctl(struct inode * break; case SNAPSHOT_GET_SWAP_PAGE: - if (!access_ok(VERIFY_WRITE, (unsigned long __user *)arg, _IOC_SIZE(cmd))) { - error = -EINVAL; - break; - } if (data->swap < 0 || data->swap >= MAX_SWAPFILES) { error = -ENODEV; break; @@ -241,7 +234,7 @@ static int snapshot_ioctl(struct inode * offset = alloc_swap_page(data->swap, data->bitmap); if (offset) { offset <<= PAGE_SHIFT; - __put_user(offset, (loff_t __user *)arg); + error = put_user(offset, (loff_t __user *)arg); } else { error = -ENOSPC; }