Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751385AbeAPJ7F (ORCPT + 1 other); Tue, 16 Jan 2018 04:59:05 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:57150 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750816AbeAPJ7C (ORCPT ); Tue, 16 Jan 2018 04:59:02 -0500 DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 5D257609D1 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=poza@codeaurora.org From: Oza Pawandeep To: Bjorn Helgaas , Philippe Ombredanne , Thomas Gleixner , Greg Kroah-Hartman , Kate Stewart , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Dongdong Liu , Keith Busch , Wei Zhang , Sinan Kaya , Timur Tabi Cc: Oza Pawandeep Subject: [PATCH v4 1/5] PCI/AER: factor out error reporting from AER Date: Tue, 16 Jan 2018 15:28:39 +0530 Message-Id: <1516096723-8013-2-git-send-email-poza@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1516096723-8013-1-git-send-email-poza@codeaurora.org> References: <1516096723-8013-1-git-send-email-poza@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: This patch factors out error reporting callbacks, which are currently tightly coupled with AER. DPC should be able to register callbacks and attmept recovery when DPC trigger event occurs. Signed-off-by: Oza Pawandeep diff --git a/drivers/pci/pcie/Makefile b/drivers/pci/pcie/Makefile index 223e4c3..d669497 100644 --- a/drivers/pci/pcie/Makefile +++ b/drivers/pci/pcie/Makefile @@ -6,7 +6,7 @@ # Build PCI Express ASPM if needed obj-$(CONFIG_PCIEASPM) += aspm.o -pcieportdrv-y := portdrv_core.o portdrv_pci.o portdrv_bus.o +pcieportdrv-y := portdrv_core.o portdrv_pci.o portdrv_bus.o pcie-err.o pcieportdrv-$(CONFIG_ACPI) += portdrv_acpi.o obj-$(CONFIG_PCIEPORTBUS) += pcieportdrv.o diff --git a/drivers/pci/pcie/aer/aerdrv.h b/drivers/pci/pcie/aer/aerdrv.h index 5449e5c..bc9db53 100644 --- a/drivers/pci/pcie/aer/aerdrv.h +++ b/drivers/pci/pcie/aer/aerdrv.h @@ -76,36 +76,6 @@ struct aer_rpc { */ }; -struct aer_broadcast_data { - enum pci_channel_state state; - enum pci_ers_result result; -}; - -static inline pci_ers_result_t merge_result(enum pci_ers_result orig, - enum pci_ers_result new) -{ - if (new == PCI_ERS_RESULT_NO_AER_DRIVER) - return PCI_ERS_RESULT_NO_AER_DRIVER; - - if (new == PCI_ERS_RESULT_NONE) - return orig; - - switch (orig) { - case PCI_ERS_RESULT_CAN_RECOVER: - case PCI_ERS_RESULT_RECOVERED: - orig = new; - break; - case PCI_ERS_RESULT_DISCONNECT: - if (new == PCI_ERS_RESULT_NEED_RESET) - orig = PCI_ERS_RESULT_NEED_RESET; - break; - default: - break; - } - - return orig; -} - extern struct bus_type pcie_port_bus_type; void aer_isr(struct work_struct *work); void aer_print_error(struct pci_dev *dev, struct aer_err_info *info); diff --git a/drivers/pci/pcie/aer/aerdrv_core.c b/drivers/pci/pcie/aer/aerdrv_core.c index 7448052..4fda843 100644 --- a/drivers/pci/pcie/aer/aerdrv_core.c +++ b/drivers/pci/pcie/aer/aerdrv_core.c @@ -234,189 +234,6 @@ static bool find_source_device(struct pci_dev *parent, return true; } -static int report_error_detected(struct pci_dev *dev, void *data) -{ - pci_ers_result_t vote; - const struct pci_error_handlers *err_handler; - struct aer_broadcast_data *result_data; - result_data = (struct aer_broadcast_data *) data; - - device_lock(&dev->dev); - dev->error_state = result_data->state; - - if (!dev->driver || - !dev->driver->err_handler || - !dev->driver->err_handler->error_detected) { - if (result_data->state == pci_channel_io_frozen && - dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) { - /* - * In case of fatal recovery, if one of down- - * stream device has no driver. We might be - * unable to recover because a later insmod - * of a driver for this device is unaware of - * its hw state. - */ - dev_printk(KERN_DEBUG, &dev->dev, "device has %s\n", - dev->driver ? - "no AER-aware driver" : "no driver"); - } - - /* - * If there's any device in the subtree that does not - * have an error_detected callback, returning - * PCI_ERS_RESULT_NO_AER_DRIVER prevents calling of - * the subsequent mmio_enabled/slot_reset/resume - * callbacks of "any" device in the subtree. All the - * devices in the subtree are left in the error state - * without recovery. - */ - - if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) - vote = PCI_ERS_RESULT_NO_AER_DRIVER; - else - vote = PCI_ERS_RESULT_NONE; - } else { - err_handler = dev->driver->err_handler; - vote = err_handler->error_detected(dev, result_data->state); - } - - result_data->result = merge_result(result_data->result, vote); - device_unlock(&dev->dev); - return 0; -} - -static int report_mmio_enabled(struct pci_dev *dev, void *data) -{ - pci_ers_result_t vote; - const struct pci_error_handlers *err_handler; - struct aer_broadcast_data *result_data; - result_data = (struct aer_broadcast_data *) data; - - device_lock(&dev->dev); - if (!dev->driver || - !dev->driver->err_handler || - !dev->driver->err_handler->mmio_enabled) - goto out; - - err_handler = dev->driver->err_handler; - vote = err_handler->mmio_enabled(dev); - result_data->result = merge_result(result_data->result, vote); -out: - device_unlock(&dev->dev); - return 0; -} - -static int report_slot_reset(struct pci_dev *dev, void *data) -{ - pci_ers_result_t vote; - const struct pci_error_handlers *err_handler; - struct aer_broadcast_data *result_data; - result_data = (struct aer_broadcast_data *) data; - - device_lock(&dev->dev); - if (!dev->driver || - !dev->driver->err_handler || - !dev->driver->err_handler->slot_reset) - goto out; - - err_handler = dev->driver->err_handler; - vote = err_handler->slot_reset(dev); - result_data->result = merge_result(result_data->result, vote); -out: - device_unlock(&dev->dev); - return 0; -} - -static int report_resume(struct pci_dev *dev, void *data) -{ - const struct pci_error_handlers *err_handler; - - device_lock(&dev->dev); - dev->error_state = pci_channel_io_normal; - - if (!dev->driver || - !dev->driver->err_handler || - !dev->driver->err_handler->resume) - goto out; - - err_handler = dev->driver->err_handler; - err_handler->resume(dev); -out: - device_unlock(&dev->dev); - return 0; -} - -/** - * broadcast_error_message - handle message broadcast to downstream drivers - * @dev: pointer to from where in a hierarchy message is broadcasted down - * @state: error state - * @error_mesg: message to print - * @cb: callback to be broadcasted - * - * Invoked during error recovery process. Once being invoked, the content - * of error severity will be broadcasted to all downstream drivers in a - * hierarchy in question. - */ -static pci_ers_result_t broadcast_error_message(struct pci_dev *dev, - enum pci_channel_state state, - char *error_mesg, - int (*cb)(struct pci_dev *, void *)) -{ - struct aer_broadcast_data result_data; - - dev_printk(KERN_DEBUG, &dev->dev, "broadcast %s message\n", error_mesg); - result_data.state = state; - if (cb == report_error_detected) - result_data.result = PCI_ERS_RESULT_CAN_RECOVER; - else - result_data.result = PCI_ERS_RESULT_RECOVERED; - - if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) { - /* - * If the error is reported by a bridge, we think this error - * is related to the downstream link of the bridge, so we - * do error recovery on all subordinates of the bridge instead - * of the bridge and clear the error status of the bridge. - */ - if (cb == report_error_detected) - dev->error_state = state; - pci_walk_bus(dev->subordinate, cb, &result_data); - if (cb == report_resume) { - pci_cleanup_aer_uncorrect_error_status(dev); - dev->error_state = pci_channel_io_normal; - } - } else { - /* - * If the error is reported by an end point, we think this - * error is related to the upstream link of the end point. - */ - if (state == pci_channel_io_normal) - /* - * the error is non fatal so the bus is ok, just invoke - * the callback for the function that logged the error. - */ - cb(dev, &result_data); - else - pci_walk_bus(dev->bus, cb, &result_data); - } - - return result_data.result; -} - -/** - * default_reset_link - default reset function - * @dev: pointer to pci_dev data structure - * - * Invoked when performing link reset on a Downstream Port or a - * Root Port with no aer driver. - */ -static pci_ers_result_t default_reset_link(struct pci_dev *dev) -{ - pci_reset_bridge_secondary_bus(dev); - dev_printk(KERN_DEBUG, &dev->dev, "downstream link has been reset\n"); - return PCI_ERS_RESULT_RECOVERED; -} - static int find_aer_service_iter(struct device *device, void *data) { struct pcie_port_service_driver *service_driver, **drv; @@ -434,7 +251,7 @@ static int find_aer_service_iter(struct device *device, void *data) return 0; } -static struct pcie_port_service_driver *find_aer_service(struct pci_dev *dev) +struct pcie_port_service_driver *pci_find_aer_service(struct pci_dev *dev) { struct pcie_port_service_driver *drv = NULL; @@ -442,108 +259,7 @@ static struct pcie_port_service_driver *find_aer_service(struct pci_dev *dev) return drv; } - -static pci_ers_result_t reset_link(struct pci_dev *dev) -{ - struct pci_dev *udev; - pci_ers_result_t status; - struct pcie_port_service_driver *driver; - - if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) { - /* Reset this port for all subordinates */ - udev = dev; - } else { - /* Reset the upstream component (likely downstream port) */ - udev = dev->bus->self; - } - - /* Use the aer driver of the component firstly */ - driver = find_aer_service(udev); - - if (driver && driver->reset_link) { - status = driver->reset_link(udev); - } else if (udev->has_secondary_link) { - status = default_reset_link(udev); - } else { - dev_printk(KERN_DEBUG, &dev->dev, - "no link-reset support at upstream device %s\n", - pci_name(udev)); - return PCI_ERS_RESULT_DISCONNECT; - } - - if (status != PCI_ERS_RESULT_RECOVERED) { - dev_printk(KERN_DEBUG, &dev->dev, - "link reset at upstream device %s failed\n", - pci_name(udev)); - return PCI_ERS_RESULT_DISCONNECT; - } - - return status; -} - -/** - * do_recovery - handle nonfatal/fatal error recovery process - * @dev: pointer to a pci_dev data structure of agent detecting an error - * @severity: error severity type - * - * Invoked when an error is nonfatal/fatal. Once being invoked, broadcast - * error detected message to all downstream drivers within a hierarchy in - * question and return the returned code. - */ -static void do_recovery(struct pci_dev *dev, int severity) -{ - pci_ers_result_t status, result = PCI_ERS_RESULT_RECOVERED; - enum pci_channel_state state; - - if (severity == AER_FATAL) - state = pci_channel_io_frozen; - else - state = pci_channel_io_normal; - - status = broadcast_error_message(dev, - state, - "error_detected", - report_error_detected); - - if (severity == AER_FATAL) { - result = reset_link(dev); - if (result != PCI_ERS_RESULT_RECOVERED) - goto failed; - } - - if (status == PCI_ERS_RESULT_CAN_RECOVER) - status = broadcast_error_message(dev, - state, - "mmio_enabled", - report_mmio_enabled); - - if (status == PCI_ERS_RESULT_NEED_RESET) { - /* - * TODO: Should call platform-specific - * functions to reset slot before calling - * drivers' slot_reset callbacks? - */ - status = broadcast_error_message(dev, - state, - "slot_reset", - report_slot_reset); - } - - if (status != PCI_ERS_RESULT_RECOVERED) - goto failed; - - broadcast_error_message(dev, - state, - "resume", - report_resume); - - dev_info(&dev->dev, "AER: Device recovery successful\n"); - return; - -failed: - /* TODO: Should kernel panic here? */ - dev_info(&dev->dev, "AER: Device recovery failed\n"); -} +EXPORT_SYMBOL(pci_find_aer_service); /** * handle_error_source - handle logging error into an event log diff --git a/drivers/pci/pcie/pcie-err.c b/drivers/pci/pcie/pcie-err.c new file mode 100644 index 0000000..76e66bb --- /dev/null +++ b/drivers/pci/pcie/pcie-err.c @@ -0,0 +1,334 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * This file implements the error recovery as a core part of PCIe error reporting. + * When a PCIe error is delivered, an error message will be collected and printed + * to console, then, an error recovery procedure will be executed by following + * the PCI error recovery rules. + * + * Copyright (C) 2006 Intel Corp. + * Tom Long Nguyen (tom.l.nguyen@intel.com) + * Zhang Yanmin (yanmin.zhang@intel.com) + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include "portdrv.h" + +struct aer_broadcast_data { + enum pci_channel_state state; + enum pci_ers_result result; +}; + +pci_ers_result_t merge_result(enum pci_ers_result orig, + enum pci_ers_result new) +{ + if (new == PCI_ERS_RESULT_NO_AER_DRIVER) + return PCI_ERS_RESULT_NO_AER_DRIVER; + + if (new == PCI_ERS_RESULT_NONE) + return orig; + + switch (orig) { + case PCI_ERS_RESULT_CAN_RECOVER: + case PCI_ERS_RESULT_RECOVERED: + orig = new; + break; + case PCI_ERS_RESULT_DISCONNECT: + if (new == PCI_ERS_RESULT_NEED_RESET) + orig = PCI_ERS_RESULT_NEED_RESET; + break; + default: + break; + } + + return orig; +} + +int report_mmio_enabled(struct pci_dev *dev, void *data) +{ + pci_ers_result_t vote; + const struct pci_error_handlers *err_handler; + struct aer_broadcast_data *result_data; + + result_data = (struct aer_broadcast_data *) data; + + device_lock(&dev->dev); + if (!dev->driver || + !dev->driver->err_handler || + !dev->driver->err_handler->mmio_enabled) + goto out; + + err_handler = dev->driver->err_handler; + vote = err_handler->mmio_enabled(dev); + result_data->result = merge_result(result_data->result, vote); +out: + device_unlock(&dev->dev); + return 0; +} + +int report_slot_reset(struct pci_dev *dev, void *data) +{ + pci_ers_result_t vote; + const struct pci_error_handlers *err_handler; + struct aer_broadcast_data *result_data; + + result_data = (struct aer_broadcast_data *) data; + + device_lock(&dev->dev); + if (!dev->driver || + !dev->driver->err_handler || + !dev->driver->err_handler->slot_reset) + goto out; + + err_handler = dev->driver->err_handler; + vote = err_handler->slot_reset(dev); + result_data->result = merge_result(result_data->result, vote); +out: + device_unlock(&dev->dev); + return 0; +} + +int report_resume(struct pci_dev *dev, void *data) +{ + const struct pci_error_handlers *err_handler; + + device_lock(&dev->dev); + dev->error_state = pci_channel_io_normal; + + if (!dev->driver || + !dev->driver->err_handler || + !dev->driver->err_handler->resume) + goto out; + + err_handler = dev->driver->err_handler; + err_handler->resume(dev); +out: + device_unlock(&dev->dev); + return 0; +} + +int report_error_detected(struct pci_dev *dev, void *data) +{ + pci_ers_result_t vote; + const struct pci_error_handlers *err_handler; + struct aer_broadcast_data *result_data; + + result_data = (struct aer_broadcast_data *) data; + + device_lock(&dev->dev); + dev->error_state = result_data->state; + + if (!dev->driver || + !dev->driver->err_handler || + !dev->driver->err_handler->error_detected) { + if (result_data->state == pci_channel_io_frozen && + dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) { + /* + * In case of fatal recovery, if one of down- + * stream device has no driver. We might be + * unable to recover because a later insmod + * of a driver for this device is unaware of + * its hw state. + */ + dev_printk(KERN_DEBUG, &dev->dev, "device has %s\n", + dev->driver ? + "no error-aware driver" : "no driver"); + } + + /* + * If there's any device in the subtree that does not + * have an error_detected callback, returning + * PCI_ERS_RESULT_NO_AER_DRIVER prevents calling of + * the subsequent mmio_enabled/slot_reset/resume + * callbacks of "any" device in the subtree. All the + * devices in the subtree are left in the error state + * without recovery. + */ + + if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) + vote = PCI_ERS_RESULT_NO_AER_DRIVER; + else + vote = PCI_ERS_RESULT_NONE; + } else { + err_handler = dev->driver->err_handler; + vote = err_handler->error_detected(dev, result_data->state); + } + + result_data->result = merge_result(result_data->result, vote); + device_unlock(&dev->dev); + return 0; +} + +/** + * default_reset_link - default reset function + * @dev: pointer to pci_dev data structure + * + * Invoked when performing link reset on a Downstream Port or a + * Root Port with no aer driver. + */ +static pci_ers_result_t default_reset_link(struct pci_dev *dev) +{ + pci_reset_bridge_secondary_bus(dev); + dev_printk(KERN_DEBUG, &dev->dev, "downstream link has been reset\n"); + return PCI_ERS_RESULT_RECOVERED; +} + +pci_ers_result_t reset_link(struct pci_dev *dev) +{ + struct pci_dev *udev; + pci_ers_result_t status; + struct pcie_port_service_driver *driver = NULL; + + if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) { + /* Reset this port for all subordinates */ + udev = dev; + } else { + /* Reset the upstream component (likely downstream port) */ + udev = dev->bus->self; + } + +#if IS_ENABLED(CONFIG_PCIEAER) + /* Use the aer driver of the component firstly */ + driver = pci_find_aer_service(udev); +#endif + + if (driver && driver->reset_link) { + status = driver->reset_link(udev); + } else if (udev->has_secondary_link) { + status = default_reset_link(udev); + } else { + dev_printk(KERN_DEBUG, &dev->dev, + "no link-reset support at upstream device %s\n", + pci_name(udev)); + return PCI_ERS_RESULT_DISCONNECT; + } + + if (status != PCI_ERS_RESULT_RECOVERED) { + dev_printk(KERN_DEBUG, &dev->dev, + "link reset at upstream device %s failed\n", + pci_name(udev)); + return PCI_ERS_RESULT_DISCONNECT; + } + + return status; +} + +/** + * broadcast_error_message - handle message broadcast to downstream drivers + * @dev: pointer to from where in a hierarchy message is broadcasted down + * @state: error state + * @error_mesg: message to print + * @cb: callback to be broadcasted + * + * Invoked during error recovery process. Once being invoked, the content + * of error severity will be broadcasted to all downstream drivers in a + * hierarchy in question. + */ +pci_ers_result_t broadcast_error_message(struct pci_dev *dev, + enum pci_channel_state state, + char *error_mesg, + int (*cb)(struct pci_dev *, void *)) +{ + struct aer_broadcast_data result_data; + + dev_printk(KERN_DEBUG, &dev->dev, "broadcast %s message\n", error_mesg); + result_data.state = state; + if (cb == report_error_detected) + result_data.result = PCI_ERS_RESULT_CAN_RECOVER; + else + result_data.result = PCI_ERS_RESULT_RECOVERED; + + if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) { + /* + * If the error is reported by a bridge, we think this error + * is related to the downstream link of the bridge, so we + * do error recovery on all subordinates of the bridge instead + * of the bridge and clear the error status of the bridge. + */ + if (cb == report_error_detected) + dev->error_state = state; + pci_walk_bus(dev->subordinate, cb, &result_data); + if (cb == report_resume) { + pci_cleanup_aer_uncorrect_error_status(dev); + dev->error_state = pci_channel_io_normal; + } + } else { + /* + * If the error is reported by an end point, we think this + * error is related to the upstream link of the end point. + */ + pci_walk_bus(dev->bus, cb, &result_data); + } + + return result_data.result; +} + +/** + * do_recovery - handle nonfatal/fatal error recovery process + * @dev: pointer to a pci_dev data structure of agent detecting an error + * @severity: error severity type + * + * Invoked when an error is nonfatal/fatal. Once being invoked, broadcast + * error detected message to all downstream drivers within a hierarchy in + * question and return the returned code. + */ +void do_recovery(struct pci_dev *dev, int severity) +{ + pci_ers_result_t status, result = PCI_ERS_RESULT_RECOVERED; + enum pci_channel_state state; + + if (severity == AER_FATAL) + state = pci_channel_io_frozen; + else + state = pci_channel_io_normal; + + status = broadcast_error_message(dev, + state, + "error_detected", + report_error_detected); + + if (severity == AER_FATAL) { + result = reset_link(dev); + if (result != PCI_ERS_RESULT_RECOVERED) + goto failed; + } + + if (status == PCI_ERS_RESULT_CAN_RECOVER) + status = broadcast_error_message(dev, + state, + "mmio_enabled", + report_mmio_enabled); + + if (status == PCI_ERS_RESULT_NEED_RESET) { + /* + * TODO: Should call platform-specific + * functions to reset slot before calling + * drivers' slot_reset callbacks? + */ + status = broadcast_error_message(dev, + state, + "slot_reset", + report_slot_reset); + } + + if (status != PCI_ERS_RESULT_RECOVERED) + goto failed; + + broadcast_error_message(dev, + state, + "resume", + report_resume); + + dev_info(&dev->dev, "Device recovery successful\n"); + return; + +failed: + /* TODO: Should kernel panic here? */ + dev_info(&dev->dev, "Device recovery failed\n"); +} diff --git a/drivers/pci/pcie/portdrv.h b/drivers/pci/pcie/portdrv.h index a854bc5..4f1992d 100644 --- a/drivers/pci/pcie/portdrv.h +++ b/drivers/pci/pcie/portdrv.h @@ -79,4 +79,5 @@ static inline void pcie_port_platform_notify(struct pci_dev *port, int *mask) static inline void pcie_port_platform_notify(struct pci_dev *port, int *mask){} #endif /* !CONFIG_ACPI */ +struct pcie_port_service_driver *pci_find_aer_service(struct pci_dev *dev); #endif /* _PORTDRV_H_ */ diff --git a/include/linux/aer.h b/include/linux/aer.h index 8f87bbe..cd4f086 100644 --- a/include/linux/aer.h +++ b/include/linux/aer.h @@ -11,9 +11,9 @@ #include #include -#define AER_NONFATAL 0 -#define AER_FATAL 1 -#define AER_CORRECTABLE 2 +#define AER_NONFATAL 0 +#define AER_FATAL 1 +#define AER_CORRECTABLE 2 struct pci_dev; diff --git a/include/linux/pci.h b/include/linux/pci.h index c170c92..46fd243 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1998,6 +1998,8 @@ static inline resource_size_t pci_iov_resource_size(struct pci_dev *dev, int res void pci_hp_remove_module_link(struct pci_slot *pci_slot); #endif +void do_recovery(struct pci_dev *dev, int severity); + /** * pci_pcie_cap - get the saved PCIe capability offset * @dev: PCI device -- Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc., a Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.