From patchwork Tue May 14 14:47:26 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Changbin Du X-Patchwork-Id: 10943147 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 39BCA924 for ; Tue, 14 May 2019 14:49:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 288C5286DD for ; Tue, 14 May 2019 14:49:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1CD4F286E6; Tue, 14 May 2019 14:49:03 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7A767286DD for ; Tue, 14 May 2019 14:49:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726623AbfENOsA (ORCPT ); Tue, 14 May 2019 10:48:00 -0400 Received: from mail-pl1-f193.google.com ([209.85.214.193]:45939 "EHLO mail-pl1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726190AbfENOr7 (ORCPT ); Tue, 14 May 2019 10:47:59 -0400 Received: by mail-pl1-f193.google.com with SMTP id a5so8367895pls.12; Tue, 14 May 2019 07:47:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=jp0J+0p/jZwToTztJ3shHuInfO0FLqac4sxv0Cyq2DU=; b=E9a+EcpYix7qibWz4lvH15hIk/6fXvQBcdfdMwM98zFNWRA1lpSIRndAlF2xUVshG9 V6oOYL5b4UqatZQ6phLN//n0qJtyWC1KoCpe/en4tMVBqlCZJmL+9RO2dyhzKT7KdXa8 8ep5g5dLY2RPDviWXte10xQk7I4ck6zxqP3atOyOO5olvcKCN9tesi9KOWQnYP8QoTed TiKCfay0IAb5XE9Bj4UHdro1i6lOpeRhetAAL8PkvuBbubzNTonoOqVvp7oTFaKfaa+w RZLoMQFbBx0CIPuQQswlQtaasxgQNmZY2H0vrV2AI+EeJs7UjNTzjjv2JxPL/Baid1Zf aFeQ== 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=jp0J+0p/jZwToTztJ3shHuInfO0FLqac4sxv0Cyq2DU=; b=r6nXP70nY6w3XiwGh/6MkJea1yDFgPvaVettnGbbH1m5408D2lz3usNPHd/qgzUk5w o8C5CQIJiPi55VLPIHawwhhW6QMJ2X5ZNSrsdN0SaYdPUzx7ZuSrgq8dezcMeMyC7YpH jSkeJfRUPkSsbjeizsHXd9v5FHHPtcBXpFt9Gjy2R95Wwp8YNHGjK0TUa6QGaEuKs+q+ 6cx1lix/YACnlbJcNxlYEOsWV+N2any88gVq+Maxbkn0y8tIZlewIuHHWiX+O+02VoDb YKukwTGzyEfRDpfVB2yGcLdr+KyHz7b5PpN7LDcF6ELGwDEY73aVEyWOk9gWnGLfGWX5 Gpag== X-Gm-Message-State: APjAAAXHGnPghTcPZTZe5epjmgNb/vSh5lOsfDMD+/j0qMsAY7F1gGnB HNKmVknMXIRNppZjbQTsWBI= X-Google-Smtp-Source: APXvYqxJV2k6yF0PuKcGyol4mMYoeA0dEK6akozwHyINsrnC+4utzx93MeCBvlyV85/HwAjUsFcqwA== X-Received: by 2002:a17:902:a611:: with SMTP id u17mr2972835plq.38.1557845278561; Tue, 14 May 2019 07:47:58 -0700 (PDT) Received: from localhost.localdomain ([104.238.181.70]) by smtp.gmail.com with ESMTPSA id j12sm20461415pff.148.2019.05.14.07.47.55 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Tue, 14 May 2019 07:47:58 -0700 (PDT) From: Changbin Du To: bhelgaas@google.com, corbet@lwn.net Cc: linux-pci@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, mchehab+samsung@kernel.org, Changbin Du Subject: [PATCH v6 04/12] Documentation: PCI: convert pci-iov-howto.txt to reST Date: Tue, 14 May 2019 22:47:26 +0800 Message-Id: <20190514144734.19760-5-changbin.du@gmail.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190514144734.19760-1-changbin.du@gmail.com> References: <20190514144734.19760-1-changbin.du@gmail.com> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This converts the plain text documentation to reStructuredText format and add it to Sphinx TOC tree. No essential content change. Signed-off-by: Changbin Du Acked-by: Bjorn Helgaas Reviewed-by: Mauro Carvalho Chehab --- Documentation/PCI/index.rst | 1 + .../{pci-iov-howto.txt => pci-iov-howto.rst} | 161 ++++++++++-------- 2 files changed, 94 insertions(+), 68 deletions(-) rename Documentation/PCI/{pci-iov-howto.txt => pci-iov-howto.rst} (63%) diff --git a/Documentation/PCI/index.rst b/Documentation/PCI/index.rst index 79d6d75bbf28..0d9390298c4a 100644 --- a/Documentation/PCI/index.rst +++ b/Documentation/PCI/index.rst @@ -10,3 +10,4 @@ Linux PCI Bus Subsystem pci picebus-howto + pci-iov-howto diff --git a/Documentation/PCI/pci-iov-howto.txt b/Documentation/PCI/pci-iov-howto.rst similarity index 63% rename from Documentation/PCI/pci-iov-howto.txt rename to Documentation/PCI/pci-iov-howto.rst index d2a84151e99c..b9fd003206f1 100644 --- a/Documentation/PCI/pci-iov-howto.txt +++ b/Documentation/PCI/pci-iov-howto.rst @@ -1,14 +1,19 @@ - PCI Express I/O Virtualization Howto - Copyright (C) 2009 Intel Corporation - Yu Zhao +.. SPDX-License-Identifier: GPL-2.0 +.. include:: - Update: November 2012 - -- sysfs-based SRIOV enable-/disable-ment - Donald Dutile +==================================== +PCI Express I/O Virtualization Howto +==================================== -1. Overview +:Copyright: |copy| 2009 Intel Corporation +:Authors: - Yu Zhao + - Donald Dutile -1.1 What is SR-IOV +Overview +======== + +What is SR-IOV +-------------- Single Root I/O Virtualization (SR-IOV) is a PCI Express Extended capability which makes one physical device appear as multiple virtual @@ -23,9 +28,11 @@ Memory Space, which is used to map its register set. VF device driver operates on the register set so it can be functional and appear as a real existing PCI device. -2. User Guide +User Guide +========== -2.1 How can I enable SR-IOV capability +How can I enable SR-IOV capability +---------------------------------- Multiple methods are available for SR-IOV enablement. In the first method, the device driver (PF driver) will control the @@ -43,105 +50,123 @@ checks, e.g., check numvfs == 0 if enabling VFs, ensure numvfs <= totalvfs. The second method is the recommended method for new/future VF devices. -2.2 How can I use the Virtual Functions +How can I use the Virtual Functions +----------------------------------- The VF is treated as hot-plugged PCI devices in the kernel, so they should be able to work in the same way as real PCI devices. The VF requires device driver that is same as a normal PCI device's. -3. Developer Guide +Developer Guide +=============== -3.1 SR-IOV API +SR-IOV API +---------- To enable SR-IOV capability: -(a) For the first method, in the driver: + +(a) For the first method, in the driver:: + int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn); - 'nr_virtfn' is number of VFs to be enabled. -(b) For the second method, from sysfs: + +'nr_virtfn' is number of VFs to be enabled. + +(b) For the second method, from sysfs:: + echo 'nr_virtfn' > \ /sys/bus/pci/devices//sriov_numvfs To disable SR-IOV capability: -(a) For the first method, in the driver: + +(a) For the first method, in the driver:: + void pci_disable_sriov(struct pci_dev *dev); -(b) For the second method, from sysfs: + +(b) For the second method, from sysfs:: + echo 0 > \ /sys/bus/pci/devices//sriov_numvfs To enable auto probing VFs by a compatible driver on the host, run command below before enabling SR-IOV capabilities. This is the default behavior. +:: + echo 1 > \ /sys/bus/pci/devices//sriov_drivers_autoprobe To disable auto probing VFs by a compatible driver on the host, run command below before enabling SR-IOV capabilities. Updating this entry will not affect VFs which are already probed. +:: + echo 0 > \ /sys/bus/pci/devices//sriov_drivers_autoprobe -3.2 Usage example +Usage example +------------- Following piece of code illustrates the usage of the SR-IOV API. +:: -static int dev_probe(struct pci_dev *dev, const struct pci_device_id *id) -{ - pci_enable_sriov(dev, NR_VIRTFN); + static int dev_probe(struct pci_dev *dev, const struct pci_device_id *id) + { + pci_enable_sriov(dev, NR_VIRTFN); - ... - - return 0; -} + ... -static void dev_remove(struct pci_dev *dev) -{ - pci_disable_sriov(dev); + return 0; + } - ... -} + static void dev_remove(struct pci_dev *dev) + { + pci_disable_sriov(dev); -static int dev_suspend(struct pci_dev *dev, pm_message_t state) -{ - ... + ... + } - return 0; -} + static int dev_suspend(struct pci_dev *dev, pm_message_t state) + { + ... -static int dev_resume(struct pci_dev *dev) -{ - ... + return 0; + } - return 0; -} + static int dev_resume(struct pci_dev *dev) + { + ... -static void dev_shutdown(struct pci_dev *dev) -{ - ... -} + return 0; + } -static int dev_sriov_configure(struct pci_dev *dev, int numvfs) -{ - if (numvfs > 0) { - ... - pci_enable_sriov(dev, numvfs); + static void dev_shutdown(struct pci_dev *dev) + { ... - return numvfs; } - if (numvfs == 0) { - .... - pci_disable_sriov(dev); - ... - return 0; + + static int dev_sriov_configure(struct pci_dev *dev, int numvfs) + { + if (numvfs > 0) { + ... + pci_enable_sriov(dev, numvfs); + ... + return numvfs; + } + if (numvfs == 0) { + .... + pci_disable_sriov(dev); + ... + return 0; + } } -} - -static struct pci_driver dev_driver = { - .name = "SR-IOV Physical Function driver", - .id_table = dev_id_table, - .probe = dev_probe, - .remove = dev_remove, - .suspend = dev_suspend, - .resume = dev_resume, - .shutdown = dev_shutdown, - .sriov_configure = dev_sriov_configure, -}; + + static struct pci_driver dev_driver = { + .name = "SR-IOV Physical Function driver", + .id_table = dev_id_table, + .probe = dev_probe, + .remove = dev_remove, + .suspend = dev_suspend, + .resume = dev_resume, + .shutdown = dev_shutdown, + .sriov_configure = dev_sriov_configure, + };