From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751867AbXCEWmd (ORCPT ); Mon, 5 Mar 2007 17:42:33 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751881AbXCEWmc (ORCPT ); Mon, 5 Mar 2007 17:42:32 -0500 Received: from mtagate5.de.ibm.com ([195.212.29.154]:20236 "EHLO mtagate5.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751633AbXCEWmS (ORCPT ); Mon, 5 Mar 2007 17:42:18 -0500 Date: Mon, 5 Mar 2007 23:42:18 +0100 From: Martin Schwidefsky To: linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org Cc: cornelia.huck@de.ibm.com Subject: [S390] cio: Fix locking when calling notify function. Message-ID: <20070305224218.GI22630@skybase> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org From: Cornelia Huck [S390] cio: Fix locking when calling notify function. Make sure we hold the device lock when we modify the ccw device structure but always call the notify function without the lock held. Signed-off-by: Cornelia Huck Signed-off-by: Martin Schwidefsky --- drivers/s390/cio/device_fsm.c | 67 +++++++++++++++++++++++++++++------------- 1 files changed, 47 insertions(+), 20 deletions(-) diff -urpN linux-2.6/drivers/s390/cio/device_fsm.c linux-2.6-patched/drivers/s390/cio/device_fsm.c --- linux-2.6/drivers/s390/cio/device_fsm.c 2007-03-05 22:51:36.000000000 +0100 +++ linux-2.6-patched/drivers/s390/cio/device_fsm.c 2007-03-05 22:51:56.000000000 +0100 @@ -334,20 +334,29 @@ ccw_device_oper_notify(struct work_struc struct ccw_device *cdev; struct subchannel *sch; int ret; + unsigned long flags; priv = container_of(work, struct ccw_device_private, kick_work); cdev = priv->cdev; + spin_lock_irqsave(cdev->ccwlock, flags); sch = to_subchannel(cdev->dev.parent); - ret = (sch->driver && sch->driver->notify) ? - sch->driver->notify(&sch->dev, CIO_OPER) : 0; - if (!ret) - /* Driver doesn't want device back. */ - ccw_device_do_unreg_rereg(work); - else { + if (sch->driver && sch->driver->notify) { + spin_unlock_irqrestore(cdev->ccwlock, flags); + ret = sch->driver->notify(&sch->dev, CIO_OPER); + spin_lock_irqsave(cdev->ccwlock, flags); + } else + ret = 0; + if (ret) { /* Reenable channel measurements, if needed. */ + spin_unlock_irqrestore(cdev->ccwlock, flags); cmf_reenable(cdev); + spin_lock_irqsave(cdev->ccwlock, flags); wake_up(&cdev->private->wait_q); } + spin_unlock_irqrestore(cdev->ccwlock, flags); + if (!ret) + /* Driver doesn't want device back. */ + ccw_device_do_unreg_rereg(work); } /* @@ -534,15 +543,21 @@ ccw_device_nopath_notify(struct work_str struct ccw_device *cdev; struct subchannel *sch; int ret; + unsigned long flags; priv = container_of(work, struct ccw_device_private, kick_work); cdev = priv->cdev; + spin_lock_irqsave(cdev->ccwlock, flags); sch = to_subchannel(cdev->dev.parent); /* Extra sanity. */ if (sch->lpm) - return; - ret = (sch->driver && sch->driver->notify) ? - sch->driver->notify(&sch->dev, CIO_NO_PATH) : 0; + goto out_unlock; + if (sch->driver && sch->driver->notify) { + spin_unlock_irqrestore(cdev->ccwlock, flags); + ret = sch->driver->notify(&sch->dev, CIO_NO_PATH); + spin_lock_irqsave(cdev->ccwlock, flags); + } else + ret = 0; if (!ret) { if (get_device(&sch->dev)) { /* Driver doesn't want to keep device. */ @@ -562,6 +577,8 @@ ccw_device_nopath_notify(struct work_str cdev->private->state = DEV_STATE_DISCONNECTED; wake_up(&cdev->private->wait_q); } +out_unlock: + spin_unlock_irqrestore(cdev->ccwlock, flags); } void @@ -607,10 +624,13 @@ ccw_device_verify_done(struct ccw_device default: /* Reset oper notify indication after verify error. */ cdev->private->flags.donotify = 0; - PREPARE_WORK(&cdev->private->kick_work, - ccw_device_nopath_notify); - queue_work(ccw_device_notify_work, &cdev->private->kick_work); - ccw_device_done(cdev, DEV_STATE_NOT_OPER); + if (cdev->online) { + PREPARE_WORK(&cdev->private->kick_work, + ccw_device_nopath_notify); + queue_work(ccw_device_notify_work, + &cdev->private->kick_work); + } else + ccw_device_done(cdev, DEV_STATE_NOT_OPER); break; } } @@ -756,15 +776,22 @@ static void ccw_device_online_notoper(struct ccw_device *cdev, enum dev_event dev_event) { struct subchannel *sch; + int ret; sch = to_subchannel(cdev->dev.parent); - if (sch->driver->notify && - sch->driver->notify(&sch->dev, sch->lpm ? CIO_GONE : CIO_NO_PATH)) { - ccw_device_set_timeout(cdev, 0); - cdev->private->flags.fake_irb = 0; - cdev->private->state = DEV_STATE_DISCONNECTED; - wake_up(&cdev->private->wait_q); - return; + if (sch->driver->notify) { + spin_unlock_irq(cdev->ccwlock); + ret = sch->driver->notify(&sch->dev, + sch->lpm ? CIO_GONE : CIO_NO_PATH); + spin_lock_irq(cdev->ccwlock); + } else + ret = 0; + if (ret) { + ccw_device_set_timeout(cdev, 0); + cdev->private->flags.fake_irb = 0; + cdev->private->state = DEV_STATE_DISCONNECTED; + wake_up(&cdev->private->wait_q); + return; } cdev->private->state = DEV_STATE_NOT_OPER; cio_disable_subchannel(sch);