From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933357Ab0HJWK1 (ORCPT ); Tue, 10 Aug 2010 18:10:27 -0400 Received: from kroah.org ([198.145.64.141]:44858 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933355Ab0HJV77 (ORCPT ); Tue, 10 Aug 2010 17:59:59 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Alan Cox , Arnd Bergmann , Greg Kroah-Hartman Subject: [PATCH 23/68] synclink: reworking locking a bit Date: Tue, 10 Aug 2010 14:58:45 -0700 Message-Id: <1281477570-18944-23-git-send-email-gregkh@suse.de> X-Mailer: git-send-email 1.7.1 In-Reply-To: <20100810214425.GB17385@kroah.com> References: <20100810214425.GB17385@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alan Cox Use the port mutex and port lock to fix the various races. The locking still isn't totally consistent but its better than before. Wants switching to the port helpers. Signed-off-by: Alan Cox Cc: Arnd Bergmann Signed-off-by: Greg Kroah-Hartman --- drivers/char/synclink_gt.c | 12 +++++++++++- drivers/char/synclinkmp.c | 9 ++++++++- 2 files changed, 19 insertions(+), 2 deletions(-) diff --git a/drivers/char/synclink_gt.c b/drivers/char/synclink_gt.c index 3c7ac6a..5a602eb 100644 --- a/drivers/char/synclink_gt.c +++ b/drivers/char/synclink_gt.c @@ -675,12 +675,14 @@ static int open(struct tty_struct *tty, struct file *filp) goto cleanup; } + mutex_lock(&info->port.mutex); info->port.tty->low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0; spin_lock_irqsave(&info->netlock, flags); if (info->netcount) { retval = -EBUSY; spin_unlock_irqrestore(&info->netlock, flags); + mutex_unlock(&info->port.mutex); goto cleanup; } info->port.count++; @@ -692,7 +694,7 @@ static int open(struct tty_struct *tty, struct file *filp) if (retval < 0) goto cleanup; } - + mutex_unlock(&info->port.mutex); retval = block_til_ready(tty, filp, info); if (retval) { DBGINFO(("%s block_til_ready rc=%d\n", info->device_name, retval)); @@ -724,12 +726,14 @@ static void close(struct tty_struct *tty, struct file *filp) if (tty_port_close_start(&info->port, tty, filp) == 0) goto cleanup; + mutex_lock(&info->port.mutex); if (info->port.flags & ASYNC_INITIALIZED) wait_until_sent(tty, info->timeout); flush_buffer(tty); tty_ldisc_flush(tty); shutdown(info); + mutex_unlock(&info->port.mutex); tty_port_close_end(&info->port, tty); info->port.tty = NULL; @@ -740,17 +744,23 @@ cleanup: static void hangup(struct tty_struct *tty) { struct slgt_info *info = tty->driver_data; + unsigned long flags; if (sanity_check(info, tty->name, "hangup")) return; DBGINFO(("%s hangup\n", info->device_name)); flush_buffer(tty); + + mutex_lock(&info->port.mutex); shutdown(info); + spin_lock_irqsave(&info->port.lock, flags); info->port.count = 0; info->port.flags &= ~ASYNC_NORMAL_ACTIVE; info->port.tty = NULL; + spin_unlock_irqrestore(&info->port.lock, flags); + mutex_unlock(&info->port.mutex); wake_up_interruptible(&info->port.open_wait); } diff --git a/drivers/char/synclinkmp.c b/drivers/char/synclinkmp.c index 8da976b..ac447c7 100644 --- a/drivers/char/synclinkmp.c +++ b/drivers/char/synclinkmp.c @@ -812,13 +812,15 @@ static void close(struct tty_struct *tty, struct file *filp) if (tty_port_close_start(&info->port, tty, filp) == 0) goto cleanup; - + + mutex_lock(&info->port.mutex); if (info->port.flags & ASYNC_INITIALIZED) wait_until_sent(tty, info->timeout); flush_buffer(tty); tty_ldisc_flush(tty); shutdown(info); + mutex_unlock(&info->port.mutex); tty_port_close_end(&info->port, tty); info->port.tty = NULL; @@ -834,6 +836,7 @@ cleanup: static void hangup(struct tty_struct *tty) { SLMP_INFO *info = tty->driver_data; + unsigned long flags; if (debug_level >= DEBUG_LEVEL_INFO) printk("%s(%d):%s hangup()\n", @@ -842,12 +845,16 @@ static void hangup(struct tty_struct *tty) if (sanity_check(info, tty->name, "hangup")) return; + mutex_lock(&info->port.mutex); flush_buffer(tty); shutdown(info); + spin_lock_irqsave(&info->port.lock, flags); info->port.count = 0; info->port.flags &= ~ASYNC_NORMAL_ACTIVE; info->port.tty = NULL; + spin_unlock_irqrestore(&info->port.lock, flags); + mutex_unlock(&info->port.mutex); wake_up_interruptible(&info->port.open_wait); } -- 1.7.2