From patchwork Tue May 14 16:51:46 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiang Liu X-Patchwork-Id: 243769 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 102DF2C00AE for ; Wed, 15 May 2013 02:52:45 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757475Ab3ENQwW (ORCPT ); Tue, 14 May 2013 12:52:22 -0400 Received: from mail-pa0-f46.google.com ([209.85.220.46]:34688 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757437Ab3ENQwV (ORCPT ); Tue, 14 May 2013 12:52:21 -0400 Received: by mail-pa0-f46.google.com with SMTP id fa10so691858pad.19 for ; Tue, 14 May 2013 09:52:20 -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=S5ptZYjxHwtnjIV2Z1zut5YXD0xiOcS/bXIh4TQOXwg=; b=y5+QKEn5TMj/U48BdwqZoXwBgJwQxH5uuFqe6LDuvDYiyhXhqvYnxjauYLQWy4LusV WlMQTGUW8l+yDsOel1dI06xPG3j6iOSHtktLVEMfLlP5usuprGHCVAAQkxcLVRJYB7SP HTzlsx5wh8YKe1wEimADRHNsQoYKK+vbNFhkzj66VgEQN9+zmirA8nT/ptXZot4oL1b3 OiYkNlOp5kSS+9S4K91sOXOqHZ9KLaZSkdy1sG9FfJ8oZSPtSUmzzOLfL3zIhmiSzMZ5 5qg9YI/QTYFVItu+UQqjdQs74RqLXHYl4Dd3f+5CAjZbrrj36xesTnjlvu1WdqYeeqEt EsFA== X-Received: by 10.66.149.5 with SMTP id tw5mr35610047pab.87.1368550340415; Tue, 14 May 2013 09:52:20 -0700 (PDT) Received: from localhost.localdomain ([120.196.98.100]) by mx.google.com with ESMTPSA id v5sm18919924pbz.4.2013.05.14.09.52.15 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 14 May 2013 09:52:19 -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, Konrad Rzeszutek Wilk , Jeremy Fitzhardinge , "Rafael J. Wysocki" , xen-devel@lists.xensource.com, virtualization@lists.linux-foundation.org Subject: [RFC PATCH v2, part 2 02/18] PCI, core: use hotplug-safe iterators to walk PCI buses Date: Wed, 15 May 2013 00:51:46 +0800 Message-Id: <1368550322-1045-2-git-send-email-jiang.liu@huawei.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1368550322-1045-1-git-send-email-jiang.liu@huawei.com> References: <1368550322-1045-1-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 Enhance PCI core to use hotplug-safe iterators to walk PCI buses. In other words, replace pci_find_bus(), pci_find_next_bus() and pci_root_buses with pci_bus_exists(), pci_get_bus(), pci_get_next_bus() and pci_get_next_root_bus() etc. Signed-off-by: Jiang Liu Cc: Konrad Rzeszutek Wilk Cc: Jeremy Fitzhardinge Cc: "Rafael J. Wysocki" Cc: linux-pci@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: xen-devel@lists.xensource.com Cc: virtualization@lists.linux-foundation.org Acked-by: Yinghai Lu --- drivers/pci/pci-sysfs.c | 2 +- drivers/pci/pcie/pme.c | 5 +++-- drivers/pci/probe.c | 15 +++++++++------ drivers/pci/setup-bus.c | 14 ++++++-------- drivers/pci/xen-pcifront.c | 3 ++- 5 files changed, 21 insertions(+), 18 deletions(-) diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index 5b4a9d9..fcc4bb2 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -296,7 +296,7 @@ static ssize_t bus_rescan_store(struct bus_type *bus, const char *buf, if (val) { mutex_lock(&pci_remove_rescan_mutex); - while ((b = pci_find_next_bus(b)) != NULL) + for_each_pci_root_bus(b) pci_rescan_bus(b); mutex_unlock(&pci_remove_rescan_mutex); } diff --git a/drivers/pci/pcie/pme.c b/drivers/pci/pcie/pme.c index 795db1f..1ed38a3 100644 --- a/drivers/pci/pcie/pme.c +++ b/drivers/pci/pcie/pme.c @@ -132,7 +132,7 @@ static bool pcie_pme_from_pci_bridge(struct pci_bus *bus, u8 devfn) static void pcie_pme_handle_request(struct pci_dev *port, u16 req_id) { u8 busnr = req_id >> 8, devfn = req_id & 0xff; - struct pci_bus *bus; + struct pci_bus *bus = NULL; struct pci_dev *dev; bool found = false; @@ -161,7 +161,7 @@ static void pcie_pme_handle_request(struct pci_dev *port, u16 req_id) } /* Second, find the bus the source device is on. */ - bus = pci_find_bus(pci_domain_nr(port->bus), busnr); + bus = pci_get_bus(pci_domain_nr(port->bus), busnr); if (!bus) goto out; @@ -206,6 +206,7 @@ static void pcie_pme_handle_request(struct pci_dev *port, u16 req_id) } out: + pci_bus_put(bus); if (!found) dev_dbg(&port->dev, "Spurious native PME interrupt!\n"); } diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 6b77333..cc5e432 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -733,7 +733,7 @@ static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max) */ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass) { - struct pci_bus *child; + struct pci_bus *child = NULL; int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS); u32 buses, i, j = 0; u16 bctl; @@ -785,7 +785,7 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass) * However, we continue to descend down the hierarchy and * scan remaining child buses. */ - child = pci_find_bus(pci_domain_nr(bus), secondary); + child = pci_get_bus(pci_domain_nr(bus), secondary); if (!child) { child = pci_add_new_bus(bus, dev, secondary); if (!child) @@ -793,6 +793,7 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass) child->primary = primary; pci_bus_insert_busn_res(child, secondary, subordinate); child->bridge_ctl = bctl; + pci_bus_get(child); } cmax = pci_scan_child_bus(child); @@ -824,12 +825,13 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass) /* Prevent assigning a bus number that already exists. * This can happen when a bridge is hot-plugged, so in * this case we only re-scan this bus. */ - child = pci_find_bus(pci_domain_nr(bus), max+1); + child = pci_get_bus(pci_domain_nr(bus), max+1); if (!child) { child = pci_add_new_bus(bus, dev, ++max); if (!child) goto out; pci_bus_insert_busn_res(child, max, 0xff); + pci_bus_get(child); } buses = (buses & 0xff000000) | ((unsigned int)(child->primary) << 0) @@ -874,8 +876,7 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass) */ for (i=0; iparent) { if ((!pcibios_assign_all_busses()) && @@ -930,6 +931,7 @@ int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass) out: pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl); + pci_bus_put(child); return max; } @@ -1691,10 +1693,11 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, if (!b) return NULL; - b2 = pci_find_bus(pci_domain_nr(b), bus); + b2 = pci_get_bus(pci_domain_nr(b), bus); if (b2) { /* If we already got to this bus through a different bridge, ignore it */ dev_dbg(&b2->dev, "bus already known\n"); + pci_bus_put(b2); goto err_out; } diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 16abaaa..9a3e3f7 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -1317,12 +1317,10 @@ static int __init pci_bus_get_depth(struct pci_bus *bus) } static int __init pci_get_max_depth(void) { - int depth = 0; + int ret, depth = 0; struct pci_bus *bus; - list_for_each_entry(bus, &pci_root_buses, node) { - int ret; - + for_each_pci_root_bus(bus) { ret = pci_bus_get_depth(bus); if (ret > depth) depth = ret; @@ -1423,11 +1421,11 @@ again: add_list = &realloc_head; /* Depth first, calculate sizes and alignments of all subordinate buses. */ - list_for_each_entry(bus, &pci_root_buses, node) + for_each_pci_root_bus(bus) __pci_bus_size_bridges(bus, add_list); /* Depth last, allocate resources and update the hardware. */ - list_for_each_entry(bus, &pci_root_buses, node) + for_each_pci_root_bus(bus) __pci_bus_assign_resources(bus, add_list, &fail_head); if (add_list) BUG_ON(!list_empty(add_list)); @@ -1480,11 +1478,11 @@ again: enable_and_dump: /* Depth last, update the hardware. */ - list_for_each_entry(bus, &pci_root_buses, node) + for_each_pci_root_bus(bus) pci_enable_bridges(bus); /* dump the resource on buses */ - list_for_each_entry(bus, &pci_root_buses, node) + for_each_pci_root_bus(bus) pci_bus_dump_resources(bus); } diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c index 966abc6..816cf94 100644 --- a/drivers/pci/xen-pcifront.c +++ b/drivers/pci/xen-pcifront.c @@ -522,7 +522,7 @@ static int pcifront_rescan_root(struct pcifront_device *pdev, dev_info(&pdev->xdev->dev, "Rescanning PCI Frontend Bus %04x:%02x\n", domain, bus); - b = pci_find_bus(domain, bus); + b = pci_get_bus(domain, bus); if (!b) /* If the bus is unknown, create it. */ return pcifront_scan_root(pdev, domain, bus); @@ -534,6 +534,7 @@ static int pcifront_rescan_root(struct pcifront_device *pdev, /* Create SysFS and notify udev of the devices. Aka: "going live" */ pci_bus_add_devices(b); + pci_bus_put(b); return err; }