From patchwork Thu Jun 3 00:01:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= X-Patchwork-Id: 12295851 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,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 10BA6C4708F for ; Thu, 3 Jun 2021 00:01:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E4738613D6 for ; Thu, 3 Jun 2021 00:01:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229541AbhFCADS (ORCPT ); Wed, 2 Jun 2021 20:03:18 -0400 Received: from mail-wr1-f48.google.com ([209.85.221.48]:38589 "EHLO mail-wr1-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229656AbhFCADP (ORCPT ); Wed, 2 Jun 2021 20:03:15 -0400 Received: by mail-wr1-f48.google.com with SMTP id j14so3959296wrq.5 for ; Wed, 02 Jun 2021 17:01:16 -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:mime-version :content-transfer-encoding; bh=f5p9SON5sixAAQi522OCLFxz/ZYY3odM43R9FOOXMt8=; b=aFscYlGU7V4MhG0xh4EkDmHucrVPaVRg9saW2sAysfm+zz5jRJbMFfQjbinT7Nq8Vh 2kR0MbX3PHrMvA9LSoyHOtkj0QsQ9bJQzQBTP7EPwdBuMedL7Bdo9gkF64VYGBvTy8K9 2uS1qttRDmDaGgpaEsRKQFjJr1DHKI5Ib2txynCX9b4QM8Woc4skDxjx5L98WiXmJIm6 YcGC6Gq2k6BUl74aooO//gC39hGHH7kDm/wTIYP0Z0dCcU6OZiky5B8Dm5YubSNBRZnL 5uvfVaTYhOA6zebY7JPSJRnyThtITyu9snLg+TZdoYgmkcyWp2Q+NBG5wRJFRe7ZJI77 KXZQ== X-Gm-Message-State: AOAM533EJjt3RfDA1fJcvIKDYQZgEUneA4oYJLj2wsw4S7bGaNbZiB+P LU1EK4qO52EFcCIOAvthKlQ= X-Google-Smtp-Source: ABdhPJwQXeStDbR/r2910dCtc0V+XttuuciwA6iF6jzDL2shYKJxtK2EnUmJH8+2TCg3dBZ4JuAWUg== X-Received: by 2002:a5d:68d1:: with SMTP id p17mr19529095wrw.28.1622678475642; Wed, 02 Jun 2021 17:01:15 -0700 (PDT) Received: from workstation.lan ([95.155.85.46]) by smtp.gmail.com with ESMTPSA id c7sm1424669wrs.23.2021.06.02.17.01.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 02 Jun 2021 17:01:14 -0700 (PDT) From: =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= To: Bjorn Helgaas Cc: Logan Gunthorpe , Joe Perches , "Oliver O'Halloran" , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Tyrel Datwyler , Russell Currey , Kurt Schwemmer , Vidya Sagar , Xiongfeng Wang , linux-pci@vger.kernel.org Subject: [PATCH v6 0/6] PCI/sysfs: Use sysfs_emit() and sysfs_emit_at() in "show" functions Date: Thu, 3 Jun 2021 00:01:06 +0000 Message-Id: <20210603000112.703037-1-kw@linux.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Hello, This series aims to bring support for the sysfs_emit() and sysfs_emit_at() functions to the existing PCI-related sysfs objects. These new functions were introduced to make it less ambiguous which function is preferred when writing to the output buffer in a device attribute's "show" callback [1]. Thus, the existing PCI sysfs objects "show" functions will be converted from the using the sprintf(), snprintf() and scnprintf() functions to sysfs_emit() and sysfs_emit_at() accordingly, as the latter is aware of the PAGE_SIZE buffer limit that the sysfs object has and correctly returns the number of bytes written into the buffer. This series will also address inconsistency related to the presence (or lack of thereof) of a trailing newline in the show() functions adding it where it's currently missing. This will allow for utilities such as the "cat" command to display the result of the read from a particular sysfs object correctly in a shell. While working on this series a problem with newline handling related to how the value of the "resource_alignment" sysfs object was parsed and then persisted has been found and corrected. Also, while at it, a change enabling support for the value of "resource_alignment" previously set using either a command-line argument or through the sysfs object to be cleared at run-time was also included, and thus aligning this particular sysfs object with the behaviour of other such objects that allow for the value to be dynamically updated and cleared as required. Additionally, a fix to a potential buffer overrun that has been found in the dsm_label_utf16s_to_utf8s() function that is responsible for the character conversion from UTF16 to UTF8 of the buffer that holds the device label obtained through the ACPI _DSM mechanism is included as part of this series. Finally, a minor fix is also included in this series that has been added to ensure that the value of the "driver_override" variable is only exposed through the corresponding sysfs object when a value is set or otherwise if the value has not been set, the object would return a string representation of the NULL value. This will also align this particular sysfs object's behaviour with others, where when there is no value then nothing is returned. [1] Documentation/filesystems/sysfs.rst This series is related to: commit ad025f8 ("PCI/sysfs: Use sysfs_emit() and sysfs_emit_at() in "show" functions") Signed-off-by: Krzysztof Wilczyński --- Changes in v2: None. Changes in v3: Added Logan Gunthorpe's "Reviewed-by". Changes in v4: Separated and squashed all the trivial sysfs_emit()/sysfs_emit_at() changes into a single patch as per Bjorn Helgaas' request. Carried Logan Gunthorpe's "Reviewed-by" over. Changes in v5: Added check to the resource_alignment_show() function to ensure that there is an extra space left in the buffer for the newline character, assuming that it might be provided. Changes in v6: Added a cover letter as per Bjorn Helgaas' request. New patch addressing a potential buffer overrun in the dsm_label_utf16s_to_utf8s() function has been added. Krzysztof Wilczyński (6): PCI/sysfs: Use sysfs_emit() and sysfs_emit_at() in "show" functions PCI/sysfs: Use return value from dsm_label_utf16s_to_utf8s() directly PCI/sysfs: Fix trailing newline handling of resource_alignment_param PCI/sysfs: Add missing trailing newline to devspec_show() PCI/sysfs: Only show value when driver_override is not NULL PCI/sysfs: Fix a buffer overrun problem with dsm_label_utf16s_to_utf8s() drivers/pci/hotplug/pci_hotplug_core.c | 8 +++--- drivers/pci/hotplug/rpadlpar_sysfs.c | 4 +-- drivers/pci/hotplug/shpchp_sysfs.c | 38 ++++++++++++++------------ drivers/pci/iov.c | 12 ++++---- drivers/pci/msi.c | 8 +++--- drivers/pci/p2pdma.c | 7 ++--- drivers/pci/pci-label.c | 22 ++++++++------- drivers/pci/pci-sysfs.c | 7 +++-- drivers/pci/pci.c | 34 +++++++++++++---------- drivers/pci/pcie/aer.c | 20 ++++++++------ drivers/pci/pcie/aspm.c | 4 +-- drivers/pci/slot.c | 18 ++++++------ drivers/pci/switch/switchtec.c | 18 ++++++------ 13 files changed, 107 insertions(+), 93 deletions(-)