From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752743AbbDEXRV (ORCPT ); Sun, 5 Apr 2015 19:17:21 -0400 Received: from mail-wg0-f47.google.com ([74.125.82.47]:32911 "EHLO mail-wg0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752576AbbDEXRU (ORCPT ); Sun, 5 Apr 2015 19:17:20 -0400 From: Giedrius Statkevicius To: lidza.louina@gmail.com, markh@compro.net Cc: gregkh@linuxfoundation.org, driverdev-devel@linuxdriverproject.org, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, =?UTF-8?q?Giedrius=20Statkevi=C4=8Dius?= Subject: [PATCH 1/2] staging: dgnc: remove dead code in dgnc_tty_write() Date: Mon, 6 Apr 2015 02:16:52 +0300 Message-Id: <1428275813-26390-1-git-send-email-giedrius.statkevicius@gmail.com> X-Mailer: git-send-email 2.3.5 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Remove the dead code protected by in_user in dgnc_tty_write() because it is set to 0 and never changed to 1 thus the code in ifs never gets executed. Signed-off-by: Giedrius Statkevičius --- v2: Just remove the dead code protected by in_user and join the first and third patches. drivers/staging/dgnc/dgnc_tty.c | 45 +---------------------------------------- 1 file changed, 1 insertion(+), 44 deletions(-) diff --git a/drivers/staging/dgnc/dgnc_tty.c b/drivers/staging/dgnc/dgnc_tty.c index ce4187f..cf2eb21 100644 --- a/drivers/staging/dgnc/dgnc_tty.c +++ b/drivers/staging/dgnc/dgnc_tty.c @@ -42,16 +42,11 @@ #include "dgnc_sysfs.h" #include "dgnc_utils.h" -#define init_MUTEX(sem) sema_init(sem, 1) -#define DECLARE_MUTEX(name) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name, 1) - /* * internal variables */ static struct dgnc_board *dgnc_BoardsByMajor[256]; static unsigned char *dgnc_TmpWriteBuf; -static DECLARE_MUTEX(dgnc_TmpWriteSem); /* * Default transparent print information. @@ -1705,7 +1700,6 @@ static int dgnc_tty_write(struct tty_struct *tty, ushort tail; ushort tmask; uint remain; - int from_user = 0; if (tty == NULL || dgnc_TmpWriteBuf == NULL) return 0; @@ -1785,38 +1779,6 @@ static int dgnc_tty_write(struct tty_struct *tty, if (count <= 0) goto exit_retry; - if (from_user) { - - count = min(count, WRITEBUFLEN); - - spin_unlock_irqrestore(&ch->ch_lock, flags); - - /* - * If data is coming from user space, copy it into a temporary - * buffer so we don't get swapped out while doing the copy to - * the board. - */ - /* we're allowed to block if it's from_user */ - if (down_interruptible(&dgnc_TmpWriteSem)) - return -EINTR; - - /* - * copy_from_user() returns the number - * of bytes that could *NOT* be copied. - */ - count -= copy_from_user(dgnc_TmpWriteBuf, (const unsigned char __user *) buf, count); - - if (!count) { - up(&dgnc_TmpWriteSem); - return -EFAULT; - } - - spin_lock_irqsave(&ch->ch_lock, flags); - - buf = dgnc_TmpWriteBuf; - - } - n = count; /* @@ -1853,12 +1815,7 @@ static int dgnc_tty_write(struct tty_struct *tty, ch->ch_cpstime += (HZ * count) / ch->ch_digi.digi_maxcps; } - if (from_user) { - spin_unlock_irqrestore(&ch->ch_lock, flags); - up(&dgnc_TmpWriteSem); - } else { - spin_unlock_irqrestore(&ch->ch_lock, flags); - } + spin_unlock_irqrestore(&ch->ch_lock, flags); if (count) { /* -- 2.3.5