From patchwork Thu May 16 15:50:58 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiang Liu X-Patchwork-Id: 2578641 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: X-Original-To: patchwork-linux-pci@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id 407943FE80 for ; Thu, 16 May 2013 15:53:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753327Ab3EPPwH (ORCPT ); Thu, 16 May 2013 11:52:07 -0400 Received: from mail-pb0-f52.google.com ([209.85.160.52]:41121 "EHLO mail-pb0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754839Ab3EPPv7 (ORCPT ); Thu, 16 May 2013 11:51:59 -0400 Received: by mail-pb0-f52.google.com with SMTP id xa7so2435990pbc.39 for ; Thu, 16 May 2013 08:51:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-received:from:to:cc:subject:date:message-id:x-mailer:in-reply-to :references; bh=unmbpChqVq2nz06y9ag+lZZ2ylhxyGm6mwvbwmjl0fU=; b=iwlCSelPRukp4rYhGD8dsJezHyST4pjUZ49XFkcAQuFr2EqXoBxhrF9/0bcCZrZSHO WnpnQuDfAzLVeAFPIrQi8hWHt6ublhatRo3Jy1+al4WgyvF3ASU+R0KwDSQt3oHnCCMW w3s6WRWpviA/DKhJJtCF1wWX1XYSLALFH72U4e5xeEa7Q9AyssjerVIe5TBL0xvLV/Wv EfeYt/gprPecOk20WUOZmG0sz5aoG2/rgKmtmYLdxkn5zL24pA6XQ8e589x/lY0soLk3 /7PYPEUlYFiAjjsD2flx7kawAD4hm5S+z/MahlBLkoYFrKsI2XBNLXHaMKLiLLmja5J7 vDjQ== X-Received: by 10.68.172.5 with SMTP id ay5mr44272027pbc.73.1368719518577; Thu, 16 May 2013 08:51:58 -0700 (PDT) Received: from localhost.localdomain ([120.196.98.100]) by mx.google.com with ESMTPSA id ea15sm8026701pad.16.2013.05.16.08.51.54 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 16 May 2013 08:51:57 -0700 (PDT) From: Jiang Liu To: Bjorn Helgaas , Yinghai Lu Cc: Jiang Liu , "Rafael J . Wysocki" , Greg Kroah-Hartman , Gu Zheng , Toshi Kani , Myron Stowe , Yijing Wang , Jiang Liu , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH v2, part3 10/11] PCI, pciehp: use PCI bus lock to protect PCI device hotplug Date: Thu, 16 May 2013 23:50:58 +0800 Message-Id: <1368719459-24800-11-git-send-email-jiang.liu@huawei.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1368719459-24800-1-git-send-email-jiang.liu@huawei.com> References: <1368719459-24800-1-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 Use PCI bus lock to protect concurrent PCI device hotplug operations. Signed-off-by: Jiang Liu Cc: Yinghai Lu Cc: Yijing Wang Cc: linux-pci@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- drivers/pci/hotplug/pciehp_pci.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/pci/hotplug/pciehp_pci.c b/drivers/pci/hotplug/pciehp_pci.c index aac7a40..ddc29ae 100644 --- a/drivers/pci/hotplug/pciehp_pci.c +++ b/drivers/pci/hotplug/pciehp_pci.c @@ -51,8 +51,14 @@ int pciehp_configure_device(struct slot *p_slot) return -EINVAL; } + if (pci_bus_lock(parent, PCI_BUS_STATE_STOPPING - 1, true) < 0) { + ctrl_err(ctrl, "Parent bus has been removed\n"); + return -EBUSY; + } + num = pci_scan_slot(parent, PCI_DEVFN(0, 0)); if (num == 0) { + pci_bus_unlock(parent, true); ctrl_err(ctrl, "No new device found\n"); return -ENODEV; } @@ -72,6 +78,7 @@ int pciehp_configure_device(struct slot *p_slot) } pci_bus_add_devices(parent); + pci_bus_unlock(parent, true); return 0; } @@ -88,6 +95,12 @@ int pciehp_unconfigure_device(struct slot *p_slot) ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:00\n", __func__, pci_domain_nr(parent), parent->number); + + if (pci_bus_lock(parent, PCI_BUS_STATE_REMOVED - 1, true) < 0) { + ctrl_dbg(ctrl, "Parent bus has been removed\n"); + return 0; + } + ret = pciehp_get_adapter_status(p_slot, &presence); if (ret) presence = 0; @@ -119,5 +132,7 @@ int pciehp_unconfigure_device(struct slot *p_slot) pci_dev_put(dev); } + pci_bus_unlock(parent, true); + return rc; }