From patchwork Mon Apr 27 18:23:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sergei Miroshnichenko X-Patchwork-Id: 11513109 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A6D20913 for ; Mon, 27 Apr 2020 18:24:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8A09A214AF for ; Mon, 27 Apr 2020 18:24:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=yadro.com header.i=@yadro.com header.b="p8DoLrcO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726463AbgD0SYT (ORCPT ); Mon, 27 Apr 2020 14:24:19 -0400 Received: from mta-02.yadro.com ([89.207.88.252]:53000 "EHLO mta-01.yadro.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726362AbgD0SYT (ORCPT ); Mon, 27 Apr 2020 14:24:19 -0400 Received: from localhost (unknown [127.0.0.1]) by mta-01.yadro.com (Postfix) with ESMTP id 778134C855; Mon, 27 Apr 2020 18:24:16 +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= 1588011855; x=1589826256; bh=zXK6593vRwJaMb5TJmwihGWxT6oOmCZd4hU 6lDP62T0=; b=p8DoLrcOnz5GcaVkU0VvDcFP0OCaD/EzH75mBaFqjQpixmp+rSw EYITbZoheyyYoVF22Pz5bEbL/W0LuZNUUhkTnINxddivOhT+7i67G7OSaL1TStnF P75GSiz9Jc9QJRmxdnAnsR5b2MDoYL9GuZD5bfsGRcHWlNmxfKW9YB1Q= 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 5UKEFRFezleC; Mon, 27 Apr 2020 21:24:15 +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 A7CF74C83D; Mon, 27 Apr 2020 21:24:11 +0300 (MSK) Received: from NB-148.yadro.com (172.17.15.136) 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; Mon, 27 Apr 2020 21:24:11 +0300 From: Sergei Miroshnichenko To: CC: Bjorn Helgaas , Lukas Wunner , Stefan Roese , Andy Lavr , =?utf-8?q?Chris?= =?utf-8?q?tian_K=C3=B6nig?= , Ard Biesheuvel , David Laight , Rajat Jain , , Sergei Miroshnichenko Subject: [PATCH v8 06/24] PCI: hotplug: Recalculate every bridge window during rescan Date: Mon, 27 Apr 2020 21:23:40 +0300 Message-ID: <20200427182358.2067702-7-s.miroshnichenko@yadro.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200427182358.2067702-1-s.miroshnichenko@yadro.com> References: <20200427182358.2067702-1-s.miroshnichenko@yadro.com> MIME-Version: 1.0 X-Originating-IP: [172.17.15.136] 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 When the movable BARs feature is enabled and a rescan has been requested, release all bridge windows and recalculate them from scratch, taking into account all kinds of BARs: fixed, movable, new. Comparing to simply trying to expand bridge windows, this also employs the PCI ability to shuffle BARs within a bridge, increasing the chances to find a memory space to fit BARs of newly hot-added devices, especially if no (or not enough) gaps were reserved by the BIOS/bootloader/firmware. The last step of writing the recalculated windows to the bridges is done by the new pci_setup_bridges() function. Signed-off-by: Sergei Miroshnichenko --- drivers/pci/pci.h | 1 + drivers/pci/probe.c | 22 ++++++++++++++++++++++ drivers/pci/setup-bus.c | 9 +++++++++ 3 files changed, 32 insertions(+) diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 25e49c5b998b..c7d3c022bf35 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -286,6 +286,7 @@ void __pci_bus_assign_resources(const struct pci_bus *bus, struct list_head *realloc_head, struct list_head *fail_head); bool pci_bus_clip_resource(struct pci_dev *dev, int idx); +void pci_bus_release_root_bridge_resources(struct pci_bus *bus); void pci_reassigndev_resource_alignment(struct pci_dev *dev); void pci_disable_bridge_window(struct pci_dev *dev); diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 1ac08b64ce83..5baad5325b16 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -3250,6 +3250,25 @@ static void pci_bus_rescan_done(struct pci_bus *bus) } } +static void pci_setup_bridges(struct pci_bus *bus) +{ + struct pci_dev *dev; + + list_for_each_entry(dev, &bus->devices, bus_list) { + struct pci_bus *child; + + if (!pci_dev_is_added(dev)) + continue; + + child = dev->subordinate; + if (child) + pci_setup_bridges(child); + } + + if (bus->self) + pci_setup_bridge(bus); +} + /** * pci_rescan_bus - Scan a PCI bus for devices * @bus: PCI bus to scan @@ -3271,8 +3290,11 @@ unsigned int pci_rescan_bus(struct pci_bus *bus) pci_bus_rescan_prepare(root); max = pci_scan_child_bus(root); + + pci_bus_release_root_bridge_resources(root); pci_assign_unassigned_root_bus_resources(root); + pci_setup_bridges(root); pci_bus_rescan_done(root); } else { max = pci_scan_child_bus(bus); diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index ffa81949a75f..00bdbc0ea817 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -1663,6 +1663,15 @@ static void pci_bus_release_bridge_resources(struct pci_bus *bus, pci_bridge_release_resources(bus, type); } +void pci_bus_release_root_bridge_resources(struct pci_bus *root_bus) +{ + pci_bus_release_bridge_resources(root_bus, IORESOURCE_IO, whole_subtree); + pci_bus_release_bridge_resources(root_bus, IORESOURCE_MEM, whole_subtree); + pci_bus_release_bridge_resources(root_bus, + IORESOURCE_MEM_64 | IORESOURCE_PREFETCH, + whole_subtree); +} + static void pci_bus_dump_res(struct pci_bus *bus) { struct resource *res;