From patchwork Fri Apr 16 20:58:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?b?S3J6eXN6dG9mIFdpbGN6ee+/ve+/vXNraQ==?= X-Patchwork-Id: 12208793 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 347A0C43461 for ; Fri, 16 Apr 2021 20:59:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1B335613E3 for ; Fri, 16 Apr 2021 20:59:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244245AbhDPU72 (ORCPT ); Fri, 16 Apr 2021 16:59:28 -0400 Received: from mail-ed1-f42.google.com ([209.85.208.42]:42918 "EHLO mail-ed1-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244287AbhDPU70 (ORCPT ); Fri, 16 Apr 2021 16:59:26 -0400 Received: by mail-ed1-f42.google.com with SMTP id d21so13717923edv.9 for ; Fri, 16 Apr 2021 13:59:01 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=GfONP6K8RDBHL1QgHrnC3J9ZMGcg9Jlord5rI4F6ZB8=; b=GNzMy3eroSIJQvwLEdUeWNIPuVHTHHnR3f3pS8gTnSZZKnWNdFSkbMql+n65XLqIwS Or4pRwENqZe1xuwViaLgiR/vutaWESh2tBISsUX1AeH8Scu9AWAozTXN8MIzIyS0lUhc D92VAOb7GDIQpvgFaut7h8JO4c2rJjM9raAG30Z1Iv9HAB6Nllq9qgdI6//LdlV39vJw 1k/NPX+zIDDCpjF5OfUnJPkyXPN79mWaF2U9THCB0d5H3TJJfweRR5ceghsToyMxn0Kb wXYBTtytYZoxZJpn1Wg1+gId4vg/8jSeiKl1Lsl26PjvJbg3GRxcQ64/cf7SdSrQI+Lo U5nA== X-Gm-Message-State: AOAM53041UfoAXk+T9jbkG05PqA+TM/hGQmqXhbTs0qJ2zGRyhRdDa1p e8YpiWQtZfS6v0drUN3/OOE= X-Google-Smtp-Source: ABdhPJxxToO5ngxNP860ld5HXeJk7n59ZjptozTNcha06u25Aw4JdMdWzTlKjGBDWVqzm4D7/kxkmA== X-Received: by 2002:a05:6402:40c9:: with SMTP id z9mr12385865edb.24.1618606740845; Fri, 16 Apr 2021 13:59:00 -0700 (PDT) Received: from workstation.lan ([95.155.85.46]) by smtp.gmail.com with ESMTPSA id n11sm5103864ejg.43.2021.04.16.13.58.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 16 Apr 2021 13:59:00 -0700 (PDT) From: =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= To: Bjorn Helgaas Cc: =?utf-8?q?Pali_Roh=C3=A1r?= , "Oliver O'Halloran" , Greg Kroah-Hartman , Daniel Vetter , Joe Perches , Dan Williams , Mauro Carvalho Chehab , David Sterba , linux-pci@vger.kernel.org Subject: [PATCH 03/20] PCI: Convert dynamic "reset" sysfs object into static Date: Fri, 16 Apr 2021 20:58:39 +0000 Message-Id: <20210416205856.3234481-4-kw@linux.com> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20210416205856.3234481-1-kw@linux.com> References: <20210416205856.3234481-1-kw@linux.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org The "reset" sysfs object, which is a write-only attribute, resides at the "/sys/bus/pci/devices/.../reset" path and allows for resetting the PCI function of a device if the device supports resetting a single function. At the moment, the static "reset" sysfs object is dynamically created when the pci_create_capabilities_sysfs() function executes that is part of the PCI sysfs objects initialisation and when a device is added: late_initcall() pci_sysfs_init() pci_create_sysfs_dev_files() pci_create_capabilities_sysfs() device_create_file() pci_bus_add_devices() pci_bus_add_device() pci_create_sysfs_dev_files() ... And dynamically removed when the pci_remove_capabilities_sysfs() function executes when the PCI device is stopped and removed: pci_stop_bus_device() pci_stop_dev() pci_remove_sysfs_dev_files() pci_remove_capabilities_sysfs() device_remove_file() This attribute does not need to be created dynamically and removed dynamically, and thus there is no need to also manage its create and remove life cycle manually as the PCI driver core can do it when the device is either added or removed. Convert the "reset" sysfs object created dynamically to static and use the .is_visible callback to check whether the device has a reset function capability and to decide if the sysfs object should be made available. Then, add a newly created attribute group to the existing group called "pci_dev_groups" to ensure that the "reset" sysfs object would be automatically included when the PCI driver initialises. Move to disable the "reset_fn" flag, and thus disabling the reset function capability of a device, to the pci_stop_dev() function from the pci_remove_capabilities_sysfs() function, as it makes more sense to disable the flag when the device is about to be stopped, rather than where sysfs objects are removed. Suggested-by: Oliver O'Halloran Suggested-by: Bjorn Helgaas Signed-off-by: Krzysztof Wilczyński --- drivers/pci/pci-sysfs.c | 51 +++++++++++++++++++---------------------- drivers/pci/remove.c | 2 ++ 2 files changed, 26 insertions(+), 27 deletions(-) diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index fa8373685140..c469d9cad0a8 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -1355,25 +1355,33 @@ static ssize_t reset_store(struct device *dev, struct device_attribute *attr, return count; } +static DEVICE_ATTR_WO(reset); -static DEVICE_ATTR(reset, 0200, NULL, reset_store); +static struct attribute *pci_dev_reset_attrs[] = { + &dev_attr_reset.attr, + NULL, +}; -static int pci_create_capabilities_sysfs(struct pci_dev *dev) +static umode_t pci_dev_reset_attr_is_visible(struct kobject *kobj, + struct attribute *a, int n) { - int retval; + struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj)); - pcie_vpd_create_sysfs_dev_files(dev); + if (!pdev->reset_fn) + return 0; - if (dev->reset_fn) { - retval = device_create_file(&dev->dev, &dev_attr_reset); - if (retval) - goto error; - } - return 0; + return a->mode; +} -error: - pcie_vpd_remove_sysfs_dev_files(dev); - return retval; +static const struct attribute_group pci_dev_reset_attr_group = { + .attrs = pci_dev_reset_attrs, + .is_visible = pci_dev_reset_attr_is_visible, +}; + + +static void pci_create_capabilities_sysfs(struct pci_dev *dev) +{ + pcie_vpd_create_sysfs_dev_files(dev); } int __must_check pci_create_sysfs_dev_files(struct pci_dev *pdev) @@ -1385,30 +1393,18 @@ int __must_check pci_create_sysfs_dev_files(struct pci_dev *pdev) retval = pci_create_resource_files(pdev); if (retval) - goto err; + return retval; /* add sysfs entries for various capabilities */ - retval = pci_create_capabilities_sysfs(pdev); - if (retval) - goto err_resource_files; - + pci_create_capabilities_sysfs(pdev); pci_create_firmware_label_files(pdev); return 0; - -err_resource_files: - pci_remove_resource_files(pdev); -err: - return retval; } static void pci_remove_capabilities_sysfs(struct pci_dev *dev) { pcie_vpd_remove_sysfs_dev_files(dev); - if (dev->reset_fn) { - device_remove_file(&dev->dev, &dev_attr_reset); - dev->reset_fn = 0; - } } /** @@ -1517,6 +1513,7 @@ const struct attribute_group *pci_dev_groups[] = { &pci_dev_group, &pci_dev_config_attr_group, &pci_dev_rom_attr_group, + &pci_dev_reset_attr_group, NULL, }; diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c index 95dec03d9f2a..dd12c2fcc7dc 100644 --- a/drivers/pci/remove.c +++ b/drivers/pci/remove.c @@ -19,6 +19,8 @@ static void pci_stop_dev(struct pci_dev *dev) pci_pme_active(dev, false); if (pci_dev_is_added(dev)) { + dev->reset_fn = 0; + device_release_driver(&dev->dev); pci_proc_detach_device(dev); pci_remove_sysfs_dev_files(dev);