xref: /openbmc/linux/drivers/vfio/pci/vfio_pci.c (revision 19e85d93)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2021, NVIDIA CORPORATION & AFFILIATES. All rights reserved
4  *
5  * Copyright (C) 2012 Red Hat, Inc.  All rights reserved.
6  *     Author: Alex Williamson <alex.williamson@redhat.com>
7  *
8  * Derived from original vfio:
9  * Copyright 2010 Cisco Systems, Inc.  All rights reserved.
10  * Author: Tom Lyon, pugs@cisco.com
11  */
12 
13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 
15 #include <linux/device.h>
16 #include <linux/eventfd.h>
17 #include <linux/file.h>
18 #include <linux/interrupt.h>
19 #include <linux/iommu.h>
20 #include <linux/module.h>
21 #include <linux/mutex.h>
22 #include <linux/notifier.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/slab.h>
25 #include <linux/types.h>
26 #include <linux/uaccess.h>
27 
28 #include "vfio_pci_priv.h"
29 
30 #define DRIVER_AUTHOR   "Alex Williamson <alex.williamson@redhat.com>"
31 #define DRIVER_DESC     "VFIO PCI - User Level meta-driver"
32 
33 static char ids[1024] __initdata;
34 module_param_string(ids, ids, sizeof(ids), 0);
35 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");
36 
37 static bool nointxmask;
38 module_param_named(nointxmask, nointxmask, bool, S_IRUGO | S_IWUSR);
39 MODULE_PARM_DESC(nointxmask,
40 		  "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.");
41 
42 #ifdef CONFIG_VFIO_PCI_VGA
43 static bool disable_vga;
44 module_param(disable_vga, bool, S_IRUGO);
45 MODULE_PARM_DESC(disable_vga, "Disable VGA resource access through vfio-pci");
46 #endif
47 
48 static bool disable_idle_d3;
49 module_param(disable_idle_d3, bool, S_IRUGO | S_IWUSR);
50 MODULE_PARM_DESC(disable_idle_d3,
51 		 "Disable using the PCI D3 low power state for idle, unused devices");
52 
53 static bool enable_sriov;
54 #ifdef CONFIG_PCI_IOV
55 module_param(enable_sriov, bool, 0644);
56 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.");
57 #endif
58 
59 static bool disable_denylist;
60 module_param(disable_denylist, bool, 0444);
61 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.");
62 
63 static bool vfio_pci_dev_in_denylist(struct pci_dev *pdev)
64 {
65 	switch (pdev->vendor) {
66 	case PCI_VENDOR_ID_INTEL:
67 		switch (pdev->device) {
68 		case PCI_DEVICE_ID_INTEL_QAT_C3XXX:
69 		case PCI_DEVICE_ID_INTEL_QAT_C3XXX_VF:
70 		case PCI_DEVICE_ID_INTEL_QAT_C62X:
71 		case PCI_DEVICE_ID_INTEL_QAT_C62X_VF:
72 		case PCI_DEVICE_ID_INTEL_QAT_DH895XCC:
73 		case PCI_DEVICE_ID_INTEL_QAT_DH895XCC_VF:
74 		case PCI_DEVICE_ID_INTEL_DSA_SPR0:
75 		case PCI_DEVICE_ID_INTEL_IAX_SPR0:
76 			return true;
77 		default:
78 			return false;
79 		}
80 	}
81 
82 	return false;
83 }
84 
85 static bool vfio_pci_is_denylisted(struct pci_dev *pdev)
86 {
87 	if (!vfio_pci_dev_in_denylist(pdev))
88 		return false;
89 
90 	if (disable_denylist) {
91 		pci_warn(pdev,
92 			 "device denylist disabled - allowing device %04x:%04x.\n",
93 			 pdev->vendor, pdev->device);
94 		return false;
95 	}
96 
97 	pci_warn(pdev, "%04x:%04x exists in vfio-pci device denylist, driver probing disallowed.\n",
98 		 pdev->vendor, pdev->device);
99 
100 	return true;
101 }
102 
103 static int vfio_pci_open_device(struct vfio_device *core_vdev)
104 {
105 	struct vfio_pci_core_device *vdev =
106 		container_of(core_vdev, struct vfio_pci_core_device, vdev);
107 	struct pci_dev *pdev = vdev->pdev;
108 	int ret;
109 
110 	ret = vfio_pci_core_enable(vdev);
111 	if (ret)
112 		return ret;
113 
114 	if (vfio_pci_is_vga(pdev) &&
115 	    pdev->vendor == PCI_VENDOR_ID_INTEL &&
116 	    IS_ENABLED(CONFIG_VFIO_PCI_IGD)) {
117 		ret = vfio_pci_igd_init(vdev);
118 		if (ret && ret != -ENODEV) {
119 			pci_warn(pdev, "Failed to setup Intel IGD regions\n");
120 			vfio_pci_core_disable(vdev);
121 			return ret;
122 		}
123 	}
124 
125 	vfio_pci_core_finish_enable(vdev);
126 
127 	return 0;
128 }
129 
130 static const struct vfio_device_ops vfio_pci_ops = {
131 	.name		= "vfio-pci",
132 	.init		= vfio_pci_core_init_dev,
133 	.release	= vfio_pci_core_release_dev,
134 	.open_device	= vfio_pci_open_device,
135 	.close_device	= vfio_pci_core_close_device,
136 	.ioctl		= vfio_pci_core_ioctl,
137 	.device_feature = vfio_pci_core_ioctl_feature,
138 	.read		= vfio_pci_core_read,
139 	.write		= vfio_pci_core_write,
140 	.mmap		= vfio_pci_core_mmap,
141 	.request	= vfio_pci_core_request,
142 	.match		= vfio_pci_core_match,
143 	.bind_iommufd	= vfio_iommufd_physical_bind,
144 	.unbind_iommufd	= vfio_iommufd_physical_unbind,
145 	.attach_ioas	= vfio_iommufd_physical_attach_ioas,
146 	.detach_ioas	= vfio_iommufd_physical_detach_ioas,
147 };
148 
149 static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
150 {
151 	struct vfio_pci_core_device *vdev;
152 	int ret;
153 
154 	if (vfio_pci_is_denylisted(pdev))
155 		return -EINVAL;
156 
157 	vdev = vfio_alloc_device(vfio_pci_core_device, vdev, &pdev->dev,
158 				 &vfio_pci_ops);
159 	if (IS_ERR(vdev))
160 		return PTR_ERR(vdev);
161 
162 	dev_set_drvdata(&pdev->dev, vdev);
163 	ret = vfio_pci_core_register_device(vdev);
164 	if (ret)
165 		goto out_put_vdev;
166 	return 0;
167 
168 out_put_vdev:
169 	vfio_put_device(&vdev->vdev);
170 	return ret;
171 }
172 
173 static void vfio_pci_remove(struct pci_dev *pdev)
174 {
175 	struct vfio_pci_core_device *vdev = dev_get_drvdata(&pdev->dev);
176 
177 	vfio_pci_core_unregister_device(vdev);
178 	vfio_put_device(&vdev->vdev);
179 }
180 
181 static int vfio_pci_sriov_configure(struct pci_dev *pdev, int nr_virtfn)
182 {
183 	struct vfio_pci_core_device *vdev = dev_get_drvdata(&pdev->dev);
184 
185 	if (!enable_sriov)
186 		return -ENOENT;
187 
188 	return vfio_pci_core_sriov_configure(vdev, nr_virtfn);
189 }
190 
191 static const struct pci_device_id vfio_pci_table[] = {
192 	{ PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_ANY_ID, PCI_ANY_ID) }, /* match all by default */
193 	{}
194 };
195 
196 MODULE_DEVICE_TABLE(pci, vfio_pci_table);
197 
198 static struct pci_driver vfio_pci_driver = {
199 	.name			= "vfio-pci",
200 	.id_table		= vfio_pci_table,
201 	.probe			= vfio_pci_probe,
202 	.remove			= vfio_pci_remove,
203 	.sriov_configure	= vfio_pci_sriov_configure,
204 	.err_handler		= &vfio_pci_core_err_handlers,
205 	.driver_managed_dma	= true,
206 };
207 
208 static void __init vfio_pci_fill_ids(void)
209 {
210 	char *p, *id;
211 	int rc;
212 
213 	/* no ids passed actually */
214 	if (ids[0] == '\0')
215 		return;
216 
217 	/* add ids specified in the module parameter */
218 	p = ids;
219 	while ((id = strsep(&p, ","))) {
220 		unsigned int vendor, device, subvendor = PCI_ANY_ID,
221 			subdevice = PCI_ANY_ID, class = 0, class_mask = 0;
222 		int fields;
223 
224 		if (!strlen(id))
225 			continue;
226 
227 		fields = sscanf(id, "%x:%x:%x:%x:%x:%x",
228 				&vendor, &device, &subvendor, &subdevice,
229 				&class, &class_mask);
230 
231 		if (fields < 2) {
232 			pr_warn("invalid id string \"%s\"\n", id);
233 			continue;
234 		}
235 
236 		rc = pci_add_dynid(&vfio_pci_driver, vendor, device,
237 				   subvendor, subdevice, class, class_mask, 0);
238 		if (rc)
239 			pr_warn("failed to add dynamic id [%04x:%04x[%04x:%04x]] class %#08x/%08x (%d)\n",
240 				vendor, device, subvendor, subdevice,
241 				class, class_mask, rc);
242 		else
243 			pr_info("add [%04x:%04x[%04x:%04x]] class %#08x/%08x\n",
244 				vendor, device, subvendor, subdevice,
245 				class, class_mask);
246 	}
247 }
248 
249 static int __init vfio_pci_init(void)
250 {
251 	int ret;
252 	bool is_disable_vga = true;
253 
254 #ifdef CONFIG_VFIO_PCI_VGA
255 	is_disable_vga = disable_vga;
256 #endif
257 
258 	vfio_pci_core_set_params(nointxmask, is_disable_vga, disable_idle_d3);
259 
260 	/* Register and scan for devices */
261 	ret = pci_register_driver(&vfio_pci_driver);
262 	if (ret)
263 		return ret;
264 
265 	vfio_pci_fill_ids();
266 
267 	if (disable_denylist)
268 		pr_warn("device denylist disabled.\n");
269 
270 	return 0;
271 }
272 module_init(vfio_pci_init);
273 
274 static void __exit vfio_pci_cleanup(void)
275 {
276 	pci_unregister_driver(&vfio_pci_driver);
277 }
278 module_exit(vfio_pci_cleanup);
279 
280 MODULE_LICENSE("GPL v2");
281 MODULE_AUTHOR(DRIVER_AUTHOR);
282 MODULE_DESCRIPTION(DRIVER_DESC);
283