Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756480Ab2FDFUl (ORCPT ); Mon, 4 Jun 2012 01:20:41 -0400 Received: from szxga03-in.huawei.com ([58.251.152.66]:35274 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756049Ab2FDFUi (ORCPT ); Mon, 4 Jun 2012 01:20:38 -0400 Date: Mon, 04 Jun 2012 13:17:00 +0800 From: Jiang Liu Subject: [RFC PATCH v1 4/6] PCI, ACPI: update PCI slot information when PCI hotplug event happens In-reply-to: <1338787022-400-1-git-send-email-jiang.liu@huawei.com> X-Originating-IP: [10.107.208.49] To: Bjorn Helgaas , Yinghai Lu , Kenji Kaneshige , Alexander Chiang Cc: Jiang Liu , Taku Izumi , Don Dutile , Greg KH , Yijing Wang , Keping Chen , linux-pci@vger.kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Message-id: <1338787022-400-4-git-send-email-jiang.liu@huawei.com> MIME-version: 1.0 X-Mailer: git-send-email 1.7.8.msysgit.0 Content-type: text/plain Content-transfer-encoding: 7BIT X-CFilter-Loop: Reflected References: <1338787022-400-1-git-send-email-jiang.liu@huawei.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4174 Lines: 150 From: Jiang Liu Currently the pci_slot driver doesn't update PCI slot information when PCI device hotplug event happens, which may cause memory leak and returning stale information to user. So hook the BUS_NOTIFY_ADD_DEVICE/BUS_NOTIFY_DEL_DEVICE events to update PCI slot information when PCI hotplug event happens. Signed-off-by: Jiang Liu --- drivers/acpi/pci_slot.c | 84 +++++++++++++++++++++++++++++++++++++++++++--- 1 files changed, 78 insertions(+), 6 deletions(-) diff --git a/drivers/acpi/pci_slot.c b/drivers/acpi/pci_slot.c index e50e31a..22cc00e 100644 --- a/drivers/acpi/pci_slot.c +++ b/drivers/acpi/pci_slot.c @@ -32,6 +32,7 @@ #include #include #include +#include #include static bool debug; @@ -123,12 +124,7 @@ struct callback_args { /* * register_slot * - * Called once for each SxFy object in the namespace. Don't worry about - * calling pci_create_slot multiple times for the same pci_bus:device, - * since each subsequent call simply bumps the refcount on the pci_slot. - * - * The number of calls to pci_destroy_slot from unregister_slot is - * symmetrical. + * Called once for each SxFy object in the namespace. */ static acpi_status register_slot(acpi_handle handle, u32 lvl, void *context, void **rv) @@ -145,6 +141,18 @@ register_slot(acpi_handle handle, u32 lvl, void *context, void **rv) if (device < 0) return AE_OK; + /* Avoid duplicated records for the same slot */ + mutex_lock(&slot_list_lock); + list_for_each_entry(slot, &slot_list, list) { + pci_slot = slot->pci_slot; + if (pci_slot && pci_slot->bus == pci_bus && + pci_slot->number == device) { + mutex_unlock(&slot_list_lock); + return AE_OK; + } + } + mutex_unlock(&slot_list_lock); + slot = kmalloc(sizeof(*slot), GFP_KERNEL); if (!slot) { err("%s: cannot allocate memory\n", __func__); @@ -354,17 +362,81 @@ static struct dmi_system_id acpi_pci_slot_dmi_table[] __initdata = { {} }; +static void acpi_pci_slot_notify_add(struct pci_dev *dev) +{ + acpi_handle handle; + struct callback_args context; + + if (!dev->subordinate) + return; + + handle = DEVICE_ACPI_HANDLE(&dev->dev); + context.root_handle = acpi_find_root_bridge_handle(dev); + if (handle && context.root_handle) { + context.pci_bus = dev->subordinate; + context.user_function = register_slot; + acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1, + register_slot, NULL, &context, NULL); + } +} + +static void acpi_pci_slot_notify_del(struct pci_dev *dev) +{ + struct acpi_pci_slot *slot, *tmp; + struct pci_bus *bus = dev->subordinate; + + if (!bus) + return; + + mutex_lock(&slot_list_lock); + list_for_each_entry_safe(slot, tmp, &slot_list, list) { + if (slot->pci_slot && slot->pci_slot->bus == bus) { + list_del(&slot->list); + pci_destroy_slot(slot->pci_slot); + put_device(&bus->dev); + kfree(slot); + } + } + mutex_unlock(&slot_list_lock); +} + +static int acpi_pci_slot_notify_fn(struct notifier_block *nb, + unsigned long event, void *data) +{ + struct device *dev = data; + + switch (event) { + case BUS_NOTIFY_ADD_DEVICE: + acpi_pci_slot_notify_add(to_pci_dev(dev)); + break; + case BUS_NOTIFY_DEL_DEVICE: + acpi_pci_slot_notify_del(to_pci_dev(dev)); + break; + default: + return NOTIFY_DONE; + } + + return NOTIFY_OK; +} + +static struct notifier_block acpi_pci_slot_notifier = { + .notifier_call = &acpi_pci_slot_notify_fn, +}; + static int __init acpi_pci_slot_init(void) { dmi_check_system(acpi_pci_slot_dmi_table); acpi_pci_register_driver(&acpi_pci_slot_driver); + bus_register_notifier(&pci_bus_type, &acpi_pci_slot_notifier); + return 0; } static void __exit acpi_pci_slot_exit(void) { + bus_unregister_notifier(&pci_bus_type, &acpi_pci_slot_notifier); acpi_pci_unregister_driver(&acpi_pci_slot_driver); } -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/