From patchwork Fri Jan 11 15:36:50 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sergei Miroshnichenko X-Patchwork-Id: 10758275 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0DCDB1874 for ; Fri, 11 Jan 2019 15:43:54 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F10DD284C0 for ; Fri, 11 Jan 2019 15:43:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E54BF284E4; Fri, 11 Jan 2019 15:43:53 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 87CE12848B for ; Fri, 11 Jan 2019 15:43:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729463AbfAKPnw (ORCPT ); Fri, 11 Jan 2019 10:43:52 -0500 Received: from mta-01.yadro.com ([89.207.88.251]:40064 "EHLO mta-01.yadro.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731201AbfAKPnw (ORCPT ); Fri, 11 Jan 2019 10:43:52 -0500 Received: from localhost (unknown [127.0.0.1]) by mta-01.yadro.com (Postfix) with ESMTP id 8BDE4419BE for ; Fri, 11 Jan 2019 15:37:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=yadro.com; h= content-type:content-type:content-transfer-encoding:mime-version :references:in-reply-to:x-mailer:message-id:date:date:subject :subject:from:from:received:received:received; s=mta-01; t= 1547221043; x=1549035444; bh=tJIKNtiK4mfCf7iorpFwf9wts60UENHeARd d3iz4n8s=; b=t9i+E4xMO8ReFZHZ07vgYQ/JLAAcT6Y4PGwlXTXPpMST7wn23ro uAyxMuPG+g0qRlSBxJ/EUckrXt6UtncOpQ1wzqGOhVYFbzngi9egoa+kqUIedDxY z6eUpxF/flg/gp5zMGoNOjMvZTF8VLswa4ASgoLqplYTbCjhIvl5VQqQ= X-Virus-Scanned: amavisd-new at yadro.com Received: from mta-01.yadro.com ([127.0.0.1]) by localhost (mta-01.yadro.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 3CikvC8qHqze for ; Fri, 11 Jan 2019 18:37:23 +0300 (MSK) Received: from T-EXCH-02.corp.yadro.com (t-exch-02.corp.yadro.com [172.17.10.102]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mta-01.yadro.com (Postfix) with ESMTPS id 5926A41996 for ; Fri, 11 Jan 2019 18:37:22 +0300 (MSK) Received: from NB-148.yadro.com (172.17.15.60) by T-EXCH-02.corp.yadro.com (172.17.10.102) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384_P384) id 15.1.669.32; Fri, 11 Jan 2019 18:37:22 +0300 From: Sergey Miroshnichenko To: CC: , Sergey Miroshnichenko Subject: [PATCH RFC v2 04/21] PCI: Pause the devices with movable BARs during rescan Date: Fri, 11 Jan 2019 18:36:50 +0300 Message-ID: <20190111153707.10140-5-s.miroshnichenko@yadro.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190111153707.10140-1-s.miroshnichenko@yadro.com> References: <20190111153707.10140-1-s.miroshnichenko@yadro.com> MIME-Version: 1.0 X-Originating-IP: [172.17.15.60] X-ClientProxiedBy: T-EXCH-01.corp.yadro.com (172.17.10.101) To T-EXCH-02.corp.yadro.com (172.17.10.102) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Drivers indicate their support of movable BARs by implementing the new rescan_prepare() and rescan_done() hooks in the struct pci_driver. All device's activity must be stopped during a rescan, and iounmap() +ioremap() must be applied to every used BAR. Signed-off-by: Sergey Miroshnichenko --- drivers/pci/probe.c | 51 +++++++++++++++++++++++++++++++++++++++++++-- include/linux/pci.h | 2 ++ 2 files changed, 51 insertions(+), 2 deletions(-) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 257b9f6f2ebb..5243a52a4081 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -3171,6 +3171,38 @@ unsigned int pci_rescan_bus_bridge_resize(struct pci_dev *bridge) return max; } +static void pci_bus_rescan_prepare(struct pci_bus *bus) +{ + struct pci_dev *dev; + + list_for_each_entry(dev, &bus->devices, bus_list) { + struct pci_bus *child = dev->subordinate; + + if (child) { + pci_bus_rescan_prepare(child); + } else if (dev->driver && + dev->driver->rescan_prepare) { + dev->driver->rescan_prepare(dev); + } + } +} + +static void pci_bus_rescan_done(struct pci_bus *bus) +{ + struct pci_dev *dev; + + list_for_each_entry(dev, &bus->devices, bus_list) { + struct pci_bus *child = dev->subordinate; + + if (child) { + pci_bus_rescan_done(child); + } else if (dev->driver && + dev->driver->rescan_done) { + dev->driver->rescan_done(dev); + } + } +} + /** * pci_rescan_bus - Scan a PCI bus for devices * @bus: PCI bus to scan @@ -3184,8 +3216,23 @@ unsigned int pci_rescan_bus(struct pci_bus *bus) { unsigned int max; - max = pci_scan_child_bus(bus); - pci_assign_unassigned_bus_resources(bus); + if (pci_movable_bars_enabled()) { + struct pci_bus *root = bus; + + while (!pci_is_root_bus(root)) + root = root->parent; + + pci_bus_rescan_prepare(root); + + max = pci_scan_child_bus(root); + pci_assign_unassigned_root_bus_resources(root); + + pci_bus_rescan_done(root); + } else { + max = pci_scan_child_bus(bus); + pci_assign_unassigned_bus_resources(bus); + } + pci_bus_add_devices(bus); return max; diff --git a/include/linux/pci.h b/include/linux/pci.h index 84751f0931cd..d87bbf9e0627 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -776,6 +776,8 @@ struct pci_driver { int (*resume)(struct pci_dev *dev); /* Device woken up */ void (*shutdown)(struct pci_dev *dev); int (*sriov_configure)(struct pci_dev *dev, int num_vfs); /* On PF */ + void (*rescan_prepare)(struct pci_dev *dev); + void (*rescan_done)(struct pci_dev *dev); const struct pci_error_handlers *err_handler; const struct attribute_group **groups; struct device_driver driver;