From patchwork Tue Mar 8 18:48:58 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Shameerali Kolothum Thodi X-Patchwork-Id: 12774192 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 999C4C433EF for ; Tue, 8 Mar 2022 18:50:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349749AbiCHSvq (ORCPT ); Tue, 8 Mar 2022 13:51:46 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51924 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349804AbiCHSvh (ORCPT ); Tue, 8 Mar 2022 13:51:37 -0500 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AF62A53B75; Tue, 8 Mar 2022 10:50:40 -0800 (PST) Received: from fraeml701-chm.china.huawei.com (unknown [172.18.147.201]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4KCkrQ5lyvz67n3l; Wed, 9 Mar 2022 02:49:10 +0800 (CST) Received: from lhreml710-chm.china.huawei.com (10.201.108.61) by fraeml701-chm.china.huawei.com (10.206.15.50) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2308.21; Tue, 8 Mar 2022 19:50:38 +0100 Received: from A2006125610.china.huawei.com (10.47.82.254) by lhreml710-chm.china.huawei.com (10.201.108.61) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Tue, 8 Mar 2022 18:50:30 +0000 From: Shameer Kolothum To: , , CC: , , , , , , , , , , , Subject: [PATCH v9 5/9] hisi_acc_vfio_pci: Restrict access to VF dev BAR2 migration region Date: Tue, 8 Mar 2022 18:48:58 +0000 Message-ID: <20220308184902.2242-6-shameerali.kolothum.thodi@huawei.com> X-Mailer: git-send-email 2.12.0.windows.1 In-Reply-To: <20220308184902.2242-1-shameerali.kolothum.thodi@huawei.com> References: <20220308184902.2242-1-shameerali.kolothum.thodi@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.47.82.254] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To lhreml710-chm.china.huawei.com (10.201.108.61) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org HiSilicon ACC VF device BAR2 region consists of both functional register space and migration control register space. Unnecessarily exposing the migration BAR region to the Guest has the potential to prevent/corrupt the Guest migration. Hence, introduce a separate struct vfio_device_ops for migration support which will override the ioctl/read/write/mmap methods to hide the migration region and limit the Guest access only to the functional register space. This will be used in subsequent patches when we add migration support to the driver. Please note that it is OK to export the entire VF BAR if migration is not supported or required as this cannot affect the PF configurations. Reviewed-by: Longfang Liu Signed-off-by: Shameer Kolothum Reviewed-by: Kevin Tian --- .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c | 126 ++++++++++++++++++ 1 file changed, 126 insertions(+) diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c index 8129c3457b3b..582ee4fa4109 100644 --- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c +++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c @@ -13,6 +13,119 @@ #include #include +static int hisi_acc_pci_rw_access_check(struct vfio_device *core_vdev, + size_t count, loff_t *ppos, + size_t *new_count) +{ + unsigned int index = VFIO_PCI_OFFSET_TO_INDEX(*ppos); + struct vfio_pci_core_device *vdev = + container_of(core_vdev, struct vfio_pci_core_device, vdev); + + if (index == VFIO_PCI_BAR2_REGION_INDEX) { + loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK; + resource_size_t end = pci_resource_len(vdev->pdev, index) / 2; + + /* Check if access is for migration control region */ + if (pos >= end) + return -EINVAL; + + *new_count = min(count, (size_t)(end - pos)); + } + + return 0; +} + +static int hisi_acc_vfio_pci_mmap(struct vfio_device *core_vdev, + struct vm_area_struct *vma) +{ + struct vfio_pci_core_device *vdev = + container_of(core_vdev, struct vfio_pci_core_device, vdev); + unsigned int index; + + index = vma->vm_pgoff >> (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT); + if (index == VFIO_PCI_BAR2_REGION_INDEX) { + u64 req_len, pgoff, req_start; + resource_size_t end = pci_resource_len(vdev->pdev, index) / 2; + + req_len = vma->vm_end - vma->vm_start; + pgoff = vma->vm_pgoff & + ((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1); + req_start = pgoff << PAGE_SHIFT; + + if (req_start + req_len > end) + return -EINVAL; + } + + return vfio_pci_core_mmap(core_vdev, vma); +} + +static ssize_t hisi_acc_vfio_pci_write(struct vfio_device *core_vdev, + const char __user *buf, size_t count, + loff_t *ppos) +{ + size_t new_count = count; + int ret; + + ret = hisi_acc_pci_rw_access_check(core_vdev, count, ppos, &new_count); + if (ret) + return ret; + + return vfio_pci_core_write(core_vdev, buf, new_count, ppos); +} + +static ssize_t hisi_acc_vfio_pci_read(struct vfio_device *core_vdev, + char __user *buf, size_t count, + loff_t *ppos) +{ + size_t new_count = count; + int ret; + + ret = hisi_acc_pci_rw_access_check(core_vdev, count, ppos, &new_count); + if (ret) + return ret; + + return vfio_pci_core_read(core_vdev, buf, new_count, ppos); +} + +static long hisi_acc_vfio_pci_ioctl(struct vfio_device *core_vdev, unsigned int cmd, + unsigned long arg) +{ + if (cmd == VFIO_DEVICE_GET_REGION_INFO) { + struct vfio_pci_core_device *vdev = + container_of(core_vdev, struct vfio_pci_core_device, vdev); + struct pci_dev *pdev = vdev->pdev; + struct vfio_region_info info; + unsigned long minsz; + + minsz = offsetofend(struct vfio_region_info, offset); + + if (copy_from_user(&info, (void __user *)arg, minsz)) + return -EFAULT; + + if (info.argsz < minsz) + return -EINVAL; + + if (info.index == VFIO_PCI_BAR2_REGION_INDEX) { + info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); + + /* + * ACC VF dev BAR2 region consists of both functional + * register space and migration control register space. + * Report only the functional region to Guest. + */ + info.size = pci_resource_len(pdev, info.index) / 2; + + info.flags = VFIO_REGION_INFO_FLAG_READ | + VFIO_REGION_INFO_FLAG_WRITE | + VFIO_REGION_INFO_FLAG_MMAP; + + return copy_to_user((void __user *)arg, &info, minsz) ? + -EFAULT : 0; + } + } + return vfio_pci_core_ioctl(core_vdev, cmd, arg); +} + static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev) { struct vfio_pci_core_device *vdev = @@ -28,6 +141,19 @@ static int hisi_acc_vfio_pci_open_device(struct vfio_device *core_vdev) return 0; } +static const struct vfio_device_ops hisi_acc_vfio_pci_migrn_ops = { + .name = "hisi-acc-vfio-pci-migration", + .open_device = hisi_acc_vfio_pci_open_device, + .close_device = vfio_pci_core_close_device, + .ioctl = hisi_acc_vfio_pci_ioctl, + .device_feature = vfio_pci_core_ioctl_feature, + .read = hisi_acc_vfio_pci_read, + .write = hisi_acc_vfio_pci_write, + .mmap = hisi_acc_vfio_pci_mmap, + .request = vfio_pci_core_request, + .match = vfio_pci_core_match, +}; + static const struct vfio_device_ops hisi_acc_vfio_pci_ops = { .name = "hisi-acc-vfio-pci", .open_device = hisi_acc_vfio_pci_open_device,