root/drivers/vfio/pci/vfio_pci.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2021, NVIDIA CORPORATION & AFFILIATES. All rights reserved
 *
 * Copyright (C) 2012 Red Hat, Inc.  All rights reserved.
 *     Author: Alex Williamson <alex.williamson@redhat.com>
 *
 * Derived from original vfio:
 * Copyright 2010 Cisco Systems, Inc.  All rights reserved.
 * Author: Tom Lyon, pugs@cisco.com
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/device.h>
#include <linux/eventfd.h>
#include <linux/file.h>
#include <linux/interrupt.h>
#include <linux/iommu.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/notifier.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/uaccess.h>

#include "vfio_pci_priv.h"

#define DRIVER_AUTHOR   "Alex Williamson <alex.williamson@redhat.com>"
#define DRIVER_DESC     "VFIO PCI - User Level meta-driver"

static char ids[1024] __initdata;
module_param_string(ids, ids, sizeof(ids), 0);
MODULE_PARM_DESC(ids, "Initial PCI IDs to add to the vfio driver, format is \"vendor:device[:subvendor[:subdevice[:class[:class_mask]]]]\" and multiple comma separated entries can be specified");

static bool nointxmask;
module_param_named(nointxmask, nointxmask, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(nointxmask,
                  "Disable support for PCI 2.3 style INTx masking.  If this resolves problems for specific devices, report lspci -vvvxxx to linux-pci@vger.kernel.org so the device can be fixed automatically via the broken_intx_masking flag.");

#ifdef CONFIG_VFIO_PCI_VGA
static bool disable_vga;
module_param(disable_vga, bool, S_IRUGO);
MODULE_PARM_DESC(disable_vga, "Disable VGA resource access through vfio-pci");
#endif

static bool disable_idle_d3;
module_param(disable_idle_d3, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(disable_idle_d3,
                 "Disable using the PCI D3 low power state for idle, unused devices");

static bool enable_sriov;
#ifdef CONFIG_PCI_IOV
module_param(enable_sriov, bool, 0644);
MODULE_PARM_DESC(enable_sriov, "Enable support for SR-IOV configuration.  Enabling SR-IOV on a PF typically requires support of the userspace PF driver, enabling VFs without such support may result in non-functional VFs or PF.");
#endif

static bool disable_denylist;
module_param(disable_denylist, bool, 0444);
MODULE_PARM_DESC(disable_denylist, "Disable use of device denylist. Disabling the denylist allows binding to devices with known errata that may lead to exploitable stability or security issues when accessed by untrusted users.");

static bool vfio_pci_dev_in_denylist(struct pci_dev *pdev)
{
        switch (pdev->vendor) {
        case PCI_VENDOR_ID_INTEL:
                switch (pdev->device) {
                case PCI_DEVICE_ID_INTEL_QAT_C3XXX:
                case PCI_DEVICE_ID_INTEL_QAT_C3XXX_VF:
                case PCI_DEVICE_ID_INTEL_QAT_C62X:
                case PCI_DEVICE_ID_INTEL_QAT_C62X_VF:
                case PCI_DEVICE_ID_INTEL_QAT_DH895XCC:
                case PCI_DEVICE_ID_INTEL_QAT_DH895XCC_VF:
                case PCI_DEVICE_ID_INTEL_DSA_SPR0:
                case PCI_DEVICE_ID_INTEL_IAX_SPR0:
                        return true;
                default:
                        return false;
                }
        }

        return false;
}

static bool vfio_pci_is_denylisted(struct pci_dev *pdev)
{
        if (!vfio_pci_dev_in_denylist(pdev))
                return false;

        if (disable_denylist) {
                pci_warn(pdev,
                         "device denylist disabled - allowing device %04x:%04x.\n",
                         pdev->vendor, pdev->device);
                return false;
        }

        pci_warn(pdev, "%04x:%04x exists in vfio-pci device denylist, driver probing disallowed.\n",
                 pdev->vendor, pdev->device);

        return true;
}

static int vfio_pci_open_device(struct vfio_device *core_vdev)
{
        struct vfio_pci_core_device *vdev =
                container_of(core_vdev, struct vfio_pci_core_device, vdev);
        struct pci_dev *pdev = vdev->pdev;
        int ret;

        ret = vfio_pci_core_enable(vdev);
        if (ret)
                return ret;

        if (vfio_pci_is_intel_display(pdev)) {
                ret = vfio_pci_igd_init(vdev);
                if (ret && ret != -ENODEV) {
                        pci_warn(pdev, "Failed to setup Intel IGD regions\n");
                        vfio_pci_core_disable(vdev);
                        return ret;
                }
        }

        vfio_pci_core_finish_enable(vdev);

        return 0;
}

static const struct vfio_device_ops vfio_pci_ops = {
        .name           = "vfio-pci",
        .init           = vfio_pci_core_init_dev,
        .release        = vfio_pci_core_release_dev,
        .open_device    = vfio_pci_open_device,
        .close_device   = vfio_pci_core_close_device,
        .ioctl          = vfio_pci_core_ioctl,
        .get_region_info_caps = vfio_pci_ioctl_get_region_info,
        .device_feature = vfio_pci_core_ioctl_feature,
        .read           = vfio_pci_core_read,
        .write          = vfio_pci_core_write,
        .mmap           = vfio_pci_core_mmap,
        .request        = vfio_pci_core_request,
        .match          = vfio_pci_core_match,
        .match_token_uuid = vfio_pci_core_match_token_uuid,
        .bind_iommufd   = vfio_iommufd_physical_bind,
        .unbind_iommufd = vfio_iommufd_physical_unbind,
        .attach_ioas    = vfio_iommufd_physical_attach_ioas,
        .detach_ioas    = vfio_iommufd_physical_detach_ioas,
        .pasid_attach_ioas      = vfio_iommufd_physical_pasid_attach_ioas,
        .pasid_detach_ioas      = vfio_iommufd_physical_pasid_detach_ioas,
};

static const struct vfio_pci_device_ops vfio_pci_dev_ops = {
        .get_dmabuf_phys = vfio_pci_core_get_dmabuf_phys,
};

static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
        struct vfio_pci_core_device *vdev;
        int ret;

        if (vfio_pci_is_denylisted(pdev))
                return -EINVAL;

        vdev = vfio_alloc_device(vfio_pci_core_device, vdev, &pdev->dev,
                                 &vfio_pci_ops);
        if (IS_ERR(vdev))
                return PTR_ERR(vdev);

        dev_set_drvdata(&pdev->dev, vdev);
        vdev->pci_ops = &vfio_pci_dev_ops;
        ret = vfio_pci_core_register_device(vdev);
        if (ret)
                goto out_put_vdev;
        return 0;

out_put_vdev:
        vfio_put_device(&vdev->vdev);
        return ret;
}

static void vfio_pci_remove(struct pci_dev *pdev)
{
        struct vfio_pci_core_device *vdev = dev_get_drvdata(&pdev->dev);

        vfio_pci_core_unregister_device(vdev);
        vfio_put_device(&vdev->vdev);
}

static int vfio_pci_sriov_configure(struct pci_dev *pdev, int nr_virtfn)
{
        struct vfio_pci_core_device *vdev = dev_get_drvdata(&pdev->dev);

        if (!enable_sriov)
                return -ENOENT;

        return vfio_pci_core_sriov_configure(vdev, nr_virtfn);
}

static const struct pci_device_id vfio_pci_table[] = {
        { PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_ANY_ID, PCI_ANY_ID) }, /* match all by default */
        {}
};

MODULE_DEVICE_TABLE(pci, vfio_pci_table);

static struct pci_driver vfio_pci_driver = {
        .name                   = "vfio-pci",
        .id_table               = vfio_pci_table,
        .probe                  = vfio_pci_probe,
        .remove                 = vfio_pci_remove,
        .sriov_configure        = vfio_pci_sriov_configure,
        .err_handler            = &vfio_pci_core_err_handlers,
        .driver_managed_dma     = true,
};

static void __init vfio_pci_fill_ids(void)
{
        char *p, *id;
        int rc;

        /* no ids passed actually */
        if (ids[0] == '\0')
                return;

        /* add ids specified in the module parameter */
        p = ids;
        while ((id = strsep(&p, ","))) {
                unsigned int vendor, device, subvendor = PCI_ANY_ID,
                        subdevice = PCI_ANY_ID, class = 0, class_mask = 0;
                int fields;

                if (!strlen(id))
                        continue;

                fields = sscanf(id, "%x:%x:%x:%x:%x:%x",
                                &vendor, &device, &subvendor, &subdevice,
                                &class, &class_mask);

                if (fields < 2) {
                        pr_warn("invalid id string \"%s\"\n", id);
                        continue;
                }

                rc = pci_add_dynid(&vfio_pci_driver, vendor, device,
                                   subvendor, subdevice, class, class_mask, 0);
                if (rc)
                        pr_warn("failed to add dynamic id [%04x:%04x[%04x:%04x]] class %#08x/%08x (%d)\n",
                                vendor, device, subvendor, subdevice,
                                class, class_mask, rc);
                else
                        pr_info("add [%04x:%04x[%04x:%04x]] class %#08x/%08x\n",
                                vendor, device, subvendor, subdevice,
                                class, class_mask);
        }
}

static int __init vfio_pci_init(void)
{
        int ret;
        bool is_disable_vga = true;

#ifdef CONFIG_VFIO_PCI_VGA
        is_disable_vga = disable_vga;
#endif

        vfio_pci_core_set_params(nointxmask, is_disable_vga, disable_idle_d3);

        /* Register and scan for devices */
        ret = pci_register_driver(&vfio_pci_driver);
        if (ret)
                return ret;

        vfio_pci_fill_ids();

        if (disable_denylist)
                pr_warn("device denylist disabled.\n");

        return 0;
}
module_init(vfio_pci_init);

static void __exit vfio_pci_cleanup(void)
{
        pci_unregister_driver(&vfio_pci_driver);
}
module_exit(vfio_pci_cleanup);

MODULE_LICENSE("GPL v2");
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);