From nobody Mon Apr 13 13:21:25 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B18CAC433FE for ; Fri, 11 Nov 2022 14:28:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234583AbiKKO2B (ORCPT ); Fri, 11 Nov 2022 09:28:01 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40896 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232851AbiKKO1c (ORCPT ); Fri, 11 Nov 2022 09:27:32 -0500 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 79A47C12; Fri, 11 Nov 2022 06:27:31 -0800 (PST) Received: from kwepemi100025.china.huawei.com (unknown [172.30.72.55]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4N81HV1c9rzHvp9; Fri, 11 Nov 2022 22:27:02 +0800 (CST) Received: from DESKTOP-27KDQMV.china.huawei.com (10.174.148.223) by kwepemi100025.china.huawei.com (7.221.188.158) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Fri, 11 Nov 2022 22:27:27 +0800 From: "Longpeng(Mike)" To: CC: , , , , , , , , Longpeng Subject: [RFC 3/4] pci/sriov: add sriov_numfs_no_scan interface Date: Fri, 11 Nov 2022 22:27:21 +0800 Message-ID: <20221111142722.1172-4-longpeng2@huawei.com> X-Mailer: git-send-email 2.25.0.windows.1 In-Reply-To: <20221111142722.1172-1-longpeng2@huawei.com> References: <20221111142722.1172-1-longpeng2@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.174.148.223] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To kwepemi100025.china.huawei.com (7.221.188.158) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Longpeng Add sriov_numfs_no_scan interface, we can enable the sriov without adding all VFs immediately. For example: echo 16 > /sys/bus/pci/devices/0000\:65\:00.0/sriov_numvfs_no_scan ( Enable 16 VFs, but not add it to the system. ) Signed-off-by: Longpeng --- drivers/pci/iov.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c index 886489aae0de..cb24d4b60e0d 100644 --- a/drivers/pci/iov.c +++ b/drivers/pci/iov.c @@ -491,6 +491,68 @@ static ssize_t sriov_numvfs_store(struct device *dev, return count; } =20 +static ssize_t sriov_numvfs_no_scan_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct pci_dev *pdev =3D to_pci_dev(dev); + int ret; + u16 num_vfs; + + if (kstrtou16(buf, 0, &num_vfs) < 0) + return -EINVAL; + + device_lock(&pdev->dev); + /* Clear the flag when disabling VFs */ + pdev->no_vf_scan =3D num_vfs ? 1 : 0; + device_unlock(&pdev->dev); + + ret =3D sriov_numvfs_common(pdev, num_vfs); + if (ret < 0) + goto fail; + + if (!num_vfs) + return count; + + /* + * Special case: set the same num_vfs again. + */ + if (test_bit(0, pdev->sriov->vf_bitmap)) + return count; + + /* + * Default to enabling VF0, we need to read some config registers that ar= e the + * same across all associated VFs. See pci_read_vf_config_common(). + */ + ret =3D pci_iov_add_virtfn(pdev, 0); + if (ret < 0) { + int rc; + + rc =3D sriov_numvfs_common(pdev, 0); + if (rc < 0) + pci_warn(pdev, "Roll back to SR-IOV disabled state failed, %d\n", rc); + + goto fail; + } + + return count; + +fail: + device_lock(&pdev->dev); + if (pdev->no_vf_scan) + pdev->no_vf_scan =3D 0; + device_unlock(&pdev->dev); + + return ret; +} + +static ssize_t sriov_numvfs_no_scan_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sriov_numvfs_show(dev, attr, buf); +} + static ssize_t sriov_offset_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -544,6 +606,7 @@ static ssize_t sriov_drivers_autoprobe_store(struct dev= ice *dev, =20 static DEVICE_ATTR_RO(sriov_totalvfs); static DEVICE_ATTR_RW(sriov_numvfs); +static DEVICE_ATTR_RW(sriov_numvfs_no_scan); static DEVICE_ATTR_RO(sriov_offset); static DEVICE_ATTR_RO(sriov_stride); static DEVICE_ATTR_RO(sriov_vf_device); @@ -552,6 +615,7 @@ static DEVICE_ATTR_RW(sriov_drivers_autoprobe); static struct attribute *sriov_pf_dev_attrs[] =3D { &dev_attr_sriov_totalvfs.attr, &dev_attr_sriov_numvfs.attr, + &dev_attr_sriov_numvfs_no_scan.attr, &dev_attr_sriov_offset.attr, &dev_attr_sriov_stride.attr, &dev_attr_sriov_vf_device.attr, --=20 2.23.0