From patchwork Fri Apr 16 20:58:37 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: 12208789 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 7A7D6C433ED for ; Fri, 16 Apr 2021 20:59:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 49121613E3 for ; Fri, 16 Apr 2021 20:59:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244362AbhDPU7Z (ORCPT ); Fri, 16 Apr 2021 16:59:25 -0400 Received: from mail-ed1-f46.google.com ([209.85.208.46]:44784 "EHLO mail-ed1-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244287AbhDPU7Y (ORCPT ); Fri, 16 Apr 2021 16:59:24 -0400 Received: by mail-ed1-f46.google.com with SMTP id f8so33828506edd.11 for ; Fri, 16 Apr 2021 13:58:59 -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=IwJd4epxm5V24MvuZj0Uq0t+/qsTh7e7QJtSqD/5M9M=; b=Mbd6ujd5OAhjQHWkpoPTtSZ4BI4F1cmzW19rEZNO2rM6R1J89mdemXGaS5tWORc1+Y 4FPA47ORa6DQiaK2LPpblGpf/bbF6r5nT3Vej6QSFuIllnRojmvLPxohLWd9M9BXft1K BfFG0P2rya1ZX2SrPABSxzqeBtb7yZBweA6UkPLDZnkpupiw6R6o5kbvFeboZj7i63gT gc817+U39bZWITVnHQvZBOHebKq0CDsPFEwwnHGDx8jcQiGRsRgzeRgyy+bPDhNLqWeb EtpPE3ZpNzoeQfyHkccjT5aKS5WwWvihxI4cCoOh8JhXqnO20s3Gsmi7KA8peu8gsMvu +3BQ== X-Gm-Message-State: AOAM530/GWLZ8mJXMgNmWF36uGHyaz0StBzWG+T68nznyJP5tXBJBbUG NjMRo2a0FUuGZ+GapKdeXTU= X-Google-Smtp-Source: ABdhPJzvRd+WEBnOHpBx0ZGOb+mAL+HRhueUDohb36XD15szMDKSzfah37WE5ZAqYdsUGoLxrgypzA== X-Received: by 2002:a05:6402:cbb:: with SMTP id cn27mr12194009edb.296.1618606738949; Fri, 16 Apr 2021 13:58:58 -0700 (PDT) Received: from workstation.lan ([95.155.85.46]) by smtp.gmail.com with ESMTPSA id n11sm5103864ejg.43.2021.04.16.13.58.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 16 Apr 2021 13:58:58 -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 01/20] PCI: Convert dynamic "config" sysfs object into static Date: Fri, 16 Apr 2021 20:58:37 +0000 Message-Id: <20210416205856.3234481-2-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 "config" sysfs object, which is a binary read-and-write attribute, resides at the "/sys/bus/pci/devices/.../config" path and allows for accessing either the legacy (PCI and PCI-X Mode 1) or the extended (PCI-X Mode 2 and PCIe) device PCI configuration space. At the moment, the static "config" sysfs object is dynamically created when the pci_create_sysfs_dev_files() 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() sysfs_create_bin_file() pci_bus_add_devices() pci_bus_add_device() pci_create_sysfs_dev_files() ... And dynamically removed when the pci_remove_sysfs_dev_files() function executes when the PCI device is stopped and removed: pci_stop_bus_device() pci_stop_dev() pci_remove_sysfs_dev_files() sysfs_remove_bin_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 "config" sysfs object created dynamically to static and use the .is_bin_visible callback to set the correct sysfs object size (either 256 bytes of 4 KiB) at runtime. Then, add a newly created attribute group to the existing group called "pci_dev_groups" to ensure that the "config" sysfs object would be automatically included when the PCI driver initializes. Suggested-by: Oliver O'Halloran Suggested-by: Bjorn Helgaas Signed-off-by: Krzysztof Wilczyński --- drivers/pci/pci-sysfs.c | 64 ++++++++++++++++------------------------- 1 file changed, 25 insertions(+), 39 deletions(-) diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index f8afd54ca3e1..dc14daf404f5 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -808,6 +808,29 @@ static ssize_t pci_write_config(struct file *filp, struct kobject *kobj, return count; } +static BIN_ATTR(config, 0644, pci_read_config, pci_write_config, 0); + +static struct bin_attribute *pci_dev_config_attrs[] = { + &bin_attr_config, + NULL, +}; + +static umode_t pci_dev_config_attr_is_visible(struct kobject *kobj, + struct bin_attribute *a, int n) +{ + struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj)); + + a->size = PCI_CFG_SPACE_SIZE; + if (pdev->cfg_size > PCI_CFG_SPACE_SIZE) + a->size = PCI_CFG_SPACE_EXP_SIZE; + + return a->attr.mode; +} + +static const struct attribute_group pci_dev_config_attr_group = { + .bin_attrs = pci_dev_config_attrs, + .is_bin_visible = pci_dev_config_attr_is_visible, +}; #ifdef HAVE_PCI_LEGACY /** @@ -1284,26 +1307,6 @@ static ssize_t pci_read_rom(struct file *filp, struct kobject *kobj, return count; } -static const struct bin_attribute pci_config_attr = { - .attr = { - .name = "config", - .mode = 0644, - }, - .size = PCI_CFG_SPACE_SIZE, - .read = pci_read_config, - .write = pci_write_config, -}; - -static const struct bin_attribute pcie_config_attr = { - .attr = { - .name = "config", - .mode = 0644, - }, - .size = PCI_CFG_SPACE_EXP_SIZE, - .read = pci_read_config, - .write = pci_write_config, -}; - static ssize_t reset_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { @@ -1355,16 +1358,9 @@ int __must_check pci_create_sysfs_dev_files(struct pci_dev *pdev) if (!sysfs_initialized) return -EACCES; - if (pdev->cfg_size > PCI_CFG_SPACE_SIZE) - retval = sysfs_create_bin_file(&pdev->dev.kobj, &pcie_config_attr); - else - retval = sysfs_create_bin_file(&pdev->dev.kobj, &pci_config_attr); - if (retval) - goto err; - retval = pci_create_resource_files(pdev); if (retval) - goto err_config_file; + goto err; /* If the device has a ROM, try to expose it in sysfs. */ rom_size = pci_resource_len(pdev, PCI_ROM_RESOURCE); @@ -1405,11 +1401,6 @@ int __must_check pci_create_sysfs_dev_files(struct pci_dev *pdev) } err_resource_files: pci_remove_resource_files(pdev); -err_config_file: - if (pdev->cfg_size > PCI_CFG_SPACE_SIZE) - sysfs_remove_bin_file(&pdev->dev.kobj, &pcie_config_attr); - else - sysfs_remove_bin_file(&pdev->dev.kobj, &pci_config_attr); err: return retval; } @@ -1435,12 +1426,6 @@ void pci_remove_sysfs_dev_files(struct pci_dev *pdev) return; pci_remove_capabilities_sysfs(pdev); - - if (pdev->cfg_size > PCI_CFG_SPACE_SIZE) - sysfs_remove_bin_file(&pdev->dev.kobj, &pcie_config_attr); - else - sysfs_remove_bin_file(&pdev->dev.kobj, &pci_config_attr); - pci_remove_resource_files(pdev); if (pdev->rom_attr) { @@ -1540,6 +1525,7 @@ static const struct attribute_group pci_dev_group = { const struct attribute_group *pci_dev_groups[] = { &pci_dev_group, + &pci_dev_config_attr_group, NULL, };