From patchwork Tue Aug 7 16:10:44 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiang Liu X-Patchwork-Id: 175722 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id EA4BE2C00AD for ; Wed, 8 Aug 2012 02:24:11 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751523Ab2HGQTR (ORCPT ); Tue, 7 Aug 2012 12:19:17 -0400 Received: from mail-gg0-f174.google.com ([209.85.161.174]:40380 "EHLO mail-gg0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752163Ab2HGQTO (ORCPT ); Tue, 7 Aug 2012 12:19:14 -0400 Received: by mail-gg0-f174.google.com with SMTP id l2so3853120ggn.19 for ; Tue, 07 Aug 2012 09:19:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; bh=3EW0PZn/+THYFPy+aBpa/PX19wXKNLYYql4DJ85458A=; b=GLK/+X/SBcMzVkqnUH9BLSX7XGCY5nHWf3zwhnzvp6vlLdqyPbAeMY2xrob9si0HMa Dsyn6Sz8hNW24Lb0NGxrsVpHIb99SPajVSig4UXNT8KhhsWGPkxIlKzHgIsFDYV+LBQq +aiB4b5F8/pxjB2EAe2LL3+bKTs2ajwsM9xfLso6RFE2p780rMcFWnZnTHHPbug9y0E0 KXlTRkoeUMYJWzdnR0+BA28CKeQFN7ivdWikWo9xcm/bTgFYBUKzEsOMEdDXA9VPh4CK LWR1+b7TCBrtgMmFFZH/EfyLdtdOxMji0fs9QFVyOIjwWRlYGJ6SDIRsWLl51kSQdCAd JGgA== Received: by 10.66.87.227 with SMTP id bb3mr27412489pab.3.1344356354102; Tue, 07 Aug 2012 09:19:14 -0700 (PDT) Received: from localhost.localdomain ([58.250.81.2]) by mx.google.com with ESMTPS id pt2sm11429362pbb.58.2012.08.07.09.19.05 (version=TLSv1/SSLv3 cipher=OTHER); Tue, 07 Aug 2012 09:19:13 -0700 (PDT) From: Jiang Liu To: Bjorn Helgaas , Don Dutile , Yinghai Lu , Greg KH , Kenji Kaneshige Cc: Jiang Liu , Taku Izumi , "Rafael J . Wysocki" , Yijing Wang , Xinwei Hu , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, Jiang Liu Subject: [RFC PATCH v1 04/22] PCI: split PCI bus device registration into two stages Date: Wed, 8 Aug 2012 00:10:44 +0800 Message-Id: <1344355862-2726-5-git-send-email-jiang.liu@huawei.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1344355862-2726-1-git-send-email-jiang.liu@huawei.com> References: <1344355862-2726-1-git-send-email-jiang.liu@huawei.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org When handling BUS_NOTIFY_ADD_DEVICE event for a new PCI bridge device, the notification handler can't hold reference count to the new PCI bus because the device object for the new bus (pci_dev->subordinate->dev) hasn't been initialized yet. Split the PCI bus device registration into two stages as below, so that the event handler could hold reference counts to the new PCI bus when handling BUS_NOTIFY_ADD_DEVICE event. 1) device_initialize(&pci_dev->dev) 2) device_initialize(&pci_dev->subordinate->dev) 3) notify BUS_NOTIFY_ADD_DEVICE event for pci_dev 4) device_add(&pci_dev->dev) 5) device_add(&pci_dev->subordinate->dev) Signed-off-by: Jiang Liu --- drivers/pci/bus.c | 2 +- drivers/pci/probe.c | 3 ++- drivers/pci/remove.c | 10 +++++----- 3 files changed, 8 insertions(+), 7 deletions(-) diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c index 4ce5ef2..e2a0c52 100644 --- a/drivers/pci/bus.c +++ b/drivers/pci/bus.c @@ -187,7 +187,7 @@ int pci_bus_add_child(struct pci_bus *bus) if (bus->bridge) bus->dev.parent = bus->bridge; - retval = device_register(&bus->dev); + retval = device_add(&bus->dev); if (retval) return retval; diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index dacca26..ad77ae5 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -456,6 +456,7 @@ static struct pci_bus * pci_alloc_bus(void) INIT_LIST_HEAD(&b->resources); b->max_bus_speed = PCI_SPEED_UNKNOWN; b->cur_bus_speed = PCI_SPEED_UNKNOWN; + device_initialize(&b->dev); } return b; } @@ -1672,7 +1673,7 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, b->dev.class = &pcibus_class; b->dev.parent = b->bridge; dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus); - error = device_register(&b->dev); + error = device_add(&b->dev); if (error) goto class_dev_reg_err; diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c index b9ac765..ba03059 100644 --- a/drivers/pci/remove.c +++ b/drivers/pci/remove.c @@ -70,11 +70,11 @@ void pci_remove_bus(struct pci_bus *pci_bus) list_del(&pci_bus->node); pci_bus_release_busn_res(pci_bus); up_write(&pci_bus_sem); - if (!pci_bus->is_added) - return; - - pci_remove_legacy_files(pci_bus); - device_unregister(&pci_bus->dev); + if (pci_bus->is_added) { + pci_remove_legacy_files(pci_bus); + device_del(&pci_bus->dev); + } + put_device(&pci_bus->dev); } EXPORT_SYMBOL(pci_remove_bus);