1/*
2 * VFIO core
3 *
4 * Copyright (C) 2012 Red Hat, Inc. All rights reserved.
5 * Author: Alex Williamson <alex.williamson@redhat.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 * Derived from original vfio:
12 * Copyright 2010 Cisco Systems, Inc. All rights reserved.
13 * Author: Tom Lyon, pugs@cisco.com
14 */
15
16#include <linux/cdev.h>
17#include <linux/compat.h>
18#include <linux/device.h>
19#include <linux/file.h>
20#include <linux/anon_inodes.h>
21#include <linux/fs.h>
22#include <linux/idr.h>
23#include <linux/iommu.h>
24#include <linux/list.h>
25#include <linux/miscdevice.h>
26#include <linux/module.h>
27#include <linux/mutex.h>
28#include <linux/pci.h>
29#include <linux/rwsem.h>
30#include <linux/sched.h>
31#include <linux/slab.h>
32#include <linux/stat.h>
33#include <linux/string.h>
34#include <linux/uaccess.h>
35#include <linux/vfio.h>
36#include <linux/wait.h>
37
38#define DRIVER_VERSION "0.3"
39#define DRIVER_AUTHOR "Alex Williamson <alex.williamson@redhat.com>"
40#define DRIVER_DESC "VFIO - User Level meta-driver"
41
42static struct vfio {
43 struct class *class;
44 struct list_head iommu_drivers_list;
45 struct mutex iommu_drivers_lock;
46 struct list_head group_list;
47 struct idr group_idr;
48 struct mutex group_lock;
49 struct cdev group_cdev;
50 dev_t group_devt;
51 wait_queue_head_t release_q;
52} vfio;
53
54struct vfio_iommu_driver {
55 const struct vfio_iommu_driver_ops *ops;
56 struct list_head vfio_next;
57};
58
59struct vfio_container {
60 struct kref kref;
61 struct list_head group_list;
62 struct rw_semaphore group_lock;
63 struct vfio_iommu_driver *iommu_driver;
64 void *iommu_data;
65 bool noiommu;
66};
67
68struct vfio_unbound_dev {
69 struct device *dev;
70 struct list_head unbound_next;
71};
72
73struct vfio_group {
74 struct kref kref;
75 int minor;
76 atomic_t container_users;
77 struct iommu_group *iommu_group;
78 struct vfio_container *container;
79 struct list_head device_list;
80 struct mutex device_lock;
81 struct device *dev;
82 struct notifier_block nb;
83 struct list_head vfio_next;
84 struct list_head container_next;
85 struct list_head unbound_list;
86 struct mutex unbound_lock;
87 atomic_t opened;
88 wait_queue_head_t container_q;
89 bool noiommu;
90 struct kvm *kvm;
91 struct blocking_notifier_head notifier;
92};
93
94struct vfio_device {
95 struct kref kref;
96 struct device *dev;
97 const struct vfio_device_ops *ops;
98 struct vfio_group *group;
99 struct list_head group_next;
100 void *device_data;
101};
102
103#ifdef CONFIG_VFIO_NOIOMMU
104static bool noiommu __read_mostly;
105module_param_named(enable_unsafe_noiommu_mode,
106 noiommu, bool, S_IRUGO | S_IWUSR);
107MODULE_PARM_DESC(enable_unsafe_noiommu_mode, "Enable UNSAFE, no-IOMMU mode. This mode provides no device isolation, no DMA translation, no host kernel protection, cannot be used for device assignment to virtual machines, requires RAWIO permissions, and will taint the kernel. If you do not know what this is for, step away. (default: false)");
108#endif
109
110/*
111 * vfio_iommu_group_{get,put} are only intended for VFIO bus driver probe
112 * and remove functions, any use cases other than acquiring the first
113 * reference for the purpose of calling vfio_add_group_dev() or removing
114 * that symmetric reference after vfio_del_group_dev() should use the raw
115 * iommu_group_{get,put} functions. In particular, vfio_iommu_group_put()
116 * removes the device from the dummy group and cannot be nested.
117 */
118struct iommu_group *vfio_iommu_group_get(struct device *dev)
119{
120 struct iommu_group *group;
121 int __maybe_unused ret;
122
123 group = iommu_group_get(dev);
124
125#ifdef CONFIG_VFIO_NOIOMMU
126 /*
127 * With noiommu enabled, an IOMMU group will be created for a device
128 * that doesn't already have one and doesn't have an iommu_ops on their
129 * bus. We set iommudata simply to be able to identify these groups
130 * as special use and for reclamation later.
131 */
132 if (group || !noiommu || iommu_present(dev->bus))
133 return group;
134
135 group = iommu_group_alloc();
136 if (IS_ERR(group))
137 return NULL;
138
139 iommu_group_set_name(group, "vfio-noiommu");
140 iommu_group_set_iommudata(group, &noiommu, NULL);
141 ret = iommu_group_add_device(group, dev);
142 if (ret) {
143 iommu_group_put(group);
144 return NULL;
145 }
146
147 /*
148 * Where to taint? At this point we've added an IOMMU group for a
149 * device that is not backed by iommu_ops, therefore any iommu_
150 * callback using iommu_ops can legitimately Oops. So, while we may
151 * be about to give a DMA capable device to a user without IOMMU
152 * protection, which is clearly taint-worthy, let's go ahead and do
153 * it here.
154 */
155 add_taint(TAINT_USER, LOCKDEP_STILL_OK);
156 dev_warn(dev, "Adding kernel taint for vfio-noiommu group on device\n");
157#endif
158
159 return group;
160}
161EXPORT_SYMBOL_GPL(vfio_iommu_group_get);
162
163void vfio_iommu_group_put(struct iommu_group *group, struct device *dev)
164{
165#ifdef CONFIG_VFIO_NOIOMMU
166 if (iommu_group_get_iommudata(group) == &noiommu)
167 iommu_group_remove_device(dev);
168#endif
169
170 iommu_group_put(group);
171}
172EXPORT_SYMBOL_GPL(vfio_iommu_group_put);
173
174#ifdef CONFIG_VFIO_NOIOMMU
175static void *vfio_noiommu_open(unsigned long arg)
176{
177 if (arg != VFIO_NOIOMMU_IOMMU)
178 return ERR_PTR(-EINVAL);
179 if (!capable(CAP_SYS_RAWIO))
180 return ERR_PTR(-EPERM);
181
182 return NULL;
183}
184
185static void vfio_noiommu_release(void *iommu_data)
186{
187}
188
189static long vfio_noiommu_ioctl(void *iommu_data,
190 unsigned int cmd, unsigned long arg)
191{
192 if (cmd == VFIO_CHECK_EXTENSION)
193 return noiommu && (arg == VFIO_NOIOMMU_IOMMU) ? 1 : 0;
194
195 return -ENOTTY;
196}
197
198static int vfio_noiommu_attach_group(void *iommu_data,
199 struct iommu_group *iommu_group)
200{
201 return iommu_group_get_iommudata(iommu_group) == &noiommu ? 0 : -EINVAL;
202}
203
204static void vfio_noiommu_detach_group(void *iommu_data,
205 struct iommu_group *iommu_group)
206{
207}
208
209static const struct vfio_iommu_driver_ops vfio_noiommu_ops = {
210 .name = "vfio-noiommu",
211 .owner = THIS_MODULE,
212 .open = vfio_noiommu_open,
213 .release = vfio_noiommu_release,
214 .ioctl = vfio_noiommu_ioctl,
215 .attach_group = vfio_noiommu_attach_group,
216 .detach_group = vfio_noiommu_detach_group,
217};
218#endif
219
220
221/**
222 * IOMMU driver registration
223 */
224int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops)
225{
226 struct vfio_iommu_driver *driver, *tmp;
227
228 driver = kzalloc(sizeof(*driver), GFP_KERNEL);
229 if (!driver)
230 return -ENOMEM;
231
232 driver->ops = ops;
233
234 mutex_lock(&vfio.iommu_drivers_lock);
235
236 /* Check for duplicates */
237 list_for_each_entry(tmp, &vfio.iommu_drivers_list, vfio_next) {
238 if (tmp->ops == ops) {
239 mutex_unlock(&vfio.iommu_drivers_lock);
240 kfree(driver);
241 return -EINVAL;
242 }
243 }
244
245 list_add(&driver->vfio_next, &vfio.iommu_drivers_list);
246
247 mutex_unlock(&vfio.iommu_drivers_lock);
248
249 return 0;
250}
251EXPORT_SYMBOL_GPL(vfio_register_iommu_driver);
252
253void vfio_unregister_iommu_driver(const struct vfio_iommu_driver_ops *ops)
254{
255 struct vfio_iommu_driver *driver;
256
257 mutex_lock(&vfio.iommu_drivers_lock);
258 list_for_each_entry(driver, &vfio.iommu_drivers_list, vfio_next) {
259 if (driver->ops == ops) {
260 list_del(&driver->vfio_next);
261 mutex_unlock(&vfio.iommu_drivers_lock);
262 kfree(driver);
263 return;
264 }
265 }
266 mutex_unlock(&vfio.iommu_drivers_lock);
267}
268EXPORT_SYMBOL_GPL(vfio_unregister_iommu_driver);
269
270/**
271 * Group minor allocation/free - both called with vfio.group_lock held
272 */
273static int vfio_alloc_group_minor(struct vfio_group *group)
274{
275 return idr_alloc(&vfio.group_idr, group, 0, MINORMASK + 1, GFP_KERNEL);
276}
277
278static void vfio_free_group_minor(int minor)
279{
280 idr_remove(&vfio.group_idr, minor);
281}
282
283static int vfio_iommu_group_notifier(struct notifier_block *nb,
284 unsigned long action, void *data);
285static void vfio_group_get(struct vfio_group *group);
286
287/**
288 * Container objects - containers are created when /dev/vfio/vfio is
289 * opened, but their lifecycle extends until the last user is done, so
290 * it's freed via kref. Must support container/group/device being
291 * closed in any order.
292 */
293static void vfio_container_get(struct vfio_container *container)
294{
295 kref_get(&container->kref);
296}
297
298static void vfio_container_release(struct kref *kref)
299{
300 struct vfio_container *container;
301 container = container_of(kref, struct vfio_container, kref);
302
303 kfree(container);
304}
305
306static void vfio_container_put(struct vfio_container *container)
307{
308 kref_put(&container->kref, vfio_container_release);
309}
310
311static void vfio_group_unlock_and_free(struct vfio_group *group)
312{
313 mutex_unlock(&vfio.group_lock);
314 /*
315 * Unregister outside of lock. A spurious callback is harmless now
316 * that the group is no longer in vfio.group_list.
317 */
318 iommu_group_unregister_notifier(group->iommu_group, &group->nb);
319 kfree(group);
320}
321
322/**
323 * Group objects - create, release, get, put, search
324 */
325static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group)
326{
327 struct vfio_group *group, *tmp;
328 struct device *dev;
329 int ret, minor;
330
331 group = kzalloc(sizeof(*group), GFP_KERNEL);
332 if (!group)
333 return ERR_PTR(-ENOMEM);
334
335 kref_init(&group->kref);
336 INIT_LIST_HEAD(&group->device_list);
337 mutex_init(&group->device_lock);
338 INIT_LIST_HEAD(&group->unbound_list);
339 mutex_init(&group->unbound_lock);
340 atomic_set(&group->container_users, 0);
341 atomic_set(&group->opened, 0);
342 init_waitqueue_head(&group->container_q);
343 group->iommu_group = iommu_group;
344#ifdef CONFIG_VFIO_NOIOMMU
345 group->noiommu = (iommu_group_get_iommudata(iommu_group) == &noiommu);
346#endif
347 BLOCKING_INIT_NOTIFIER_HEAD(&group->notifier);
348
349 group->nb.notifier_call = vfio_iommu_group_notifier;
350
351 /*
352 * blocking notifiers acquire a rwsem around registering and hold
353 * it around callback. Therefore, need to register outside of
354 * vfio.group_lock to avoid A-B/B-A contention. Our callback won't
355 * do anything unless it can find the group in vfio.group_list, so
356 * no harm in registering early.
357 */
358 ret = iommu_group_register_notifier(iommu_group, &group->nb);
359 if (ret) {
360 kfree(group);
361 return ERR_PTR(ret);
362 }
363
364 mutex_lock(&vfio.group_lock);
365
366 /* Did we race creating this group? */
367 list_for_each_entry(tmp, &vfio.group_list, vfio_next) {
368 if (tmp->iommu_group == iommu_group) {
369 vfio_group_get(tmp);
370 vfio_group_unlock_and_free(group);
371 return tmp;
372 }
373 }
374
375 minor = vfio_alloc_group_minor(group);
376 if (minor < 0) {
377 vfio_group_unlock_and_free(group);
378 return ERR_PTR(minor);
379 }
380
381 dev = device_create(vfio.class, NULL,
382 MKDEV(MAJOR(vfio.group_devt), minor),
383 group, "%s%d", group->noiommu ? "noiommu-" : "",
384 iommu_group_id(iommu_group));
385 if (IS_ERR(dev)) {
386 vfio_free_group_minor(minor);
387 vfio_group_unlock_and_free(group);
388 return ERR_CAST(dev);
389 }
390
391 group->minor = minor;
392 group->dev = dev;
393
394 list_add(&group->vfio_next, &vfio.group_list);
395
396 mutex_unlock(&vfio.group_lock);
397
398 return group;
399}
400
401/* called with vfio.group_lock held */
402static void vfio_group_release(struct kref *kref)
403{
404 struct vfio_group *group = container_of(kref, struct vfio_group, kref);
405 struct vfio_unbound_dev *unbound, *tmp;
406 struct iommu_group *iommu_group = group->iommu_group;
407
408 WARN_ON(!list_empty(&group->device_list));
409 WARN_ON(group->notifier.head);
410
411 list_for_each_entry_safe(unbound, tmp,
412 &group->unbound_list, unbound_next) {
413 list_del(&unbound->unbound_next);
414 kfree(unbound);
415 }
416
417 device_destroy(vfio.class, MKDEV(MAJOR(vfio.group_devt), group->minor));
418 list_del(&group->vfio_next);
419 vfio_free_group_minor(group->minor);
420 vfio_group_unlock_and_free(group);
421 iommu_group_put(iommu_group);
422}
423
424static void vfio_group_put(struct vfio_group *group)
425{
426 kref_put_mutex(&group->kref, vfio_group_release, &vfio.group_lock);
427}
428
429struct vfio_group_put_work {
430 struct work_struct work;
431 struct vfio_group *group;
432};
433
434static void vfio_group_put_bg(struct work_struct *work)
435{
436 struct vfio_group_put_work *do_work;
437
438 do_work = container_of(work, struct vfio_group_put_work, work);
439
440 vfio_group_put(do_work->group);
441 kfree(do_work);
442}
443
444static void vfio_group_schedule_put(struct vfio_group *group)
445{
446 struct vfio_group_put_work *do_work;
447
448 do_work = kmalloc(sizeof(*do_work), GFP_KERNEL);
449 if (WARN_ON(!do_work))
450 return;
451
452 INIT_WORK(&do_work->work, vfio_group_put_bg);
453 do_work->group = group;
454 schedule_work(&do_work->work);
455}
456
457/* Assume group_lock or group reference is held */
458static void vfio_group_get(struct vfio_group *group)
459{
460 kref_get(&group->kref);
461}
462
463/*
464 * Not really a try as we will sleep for mutex, but we need to make
465 * sure the group pointer is valid under lock and get a reference.
466 */
467static struct vfio_group *vfio_group_try_get(struct vfio_group *group)
468{
469 struct vfio_group *target = group;
470
471 mutex_lock(&vfio.group_lock);
472 list_for_each_entry(group, &vfio.group_list, vfio_next) {
473 if (group == target) {
474 vfio_group_get(group);
475 mutex_unlock(&vfio.group_lock);
476 return group;
477 }
478 }
479 mutex_unlock(&vfio.group_lock);
480
481 return NULL;
482}
483
484static
485struct vfio_group *vfio_group_get_from_iommu(struct iommu_group *iommu_group)
486{
487 struct vfio_group *group;
488
489 mutex_lock(&vfio.group_lock);
490 list_for_each_entry(group, &vfio.group_list, vfio_next) {
491 if (group->iommu_group == iommu_group) {
492 vfio_group_get(group);
493 mutex_unlock(&vfio.group_lock);
494 return group;
495 }
496 }
497 mutex_unlock(&vfio.group_lock);
498
499 return NULL;
500}
501
502static struct vfio_group *vfio_group_get_from_minor(int minor)
503{
504 struct vfio_group *group;
505
506 mutex_lock(&vfio.group_lock);
507 group = idr_find(&vfio.group_idr, minor);
508 if (!group) {
509 mutex_unlock(&vfio.group_lock);
510 return NULL;
511 }
512 vfio_group_get(group);
513 mutex_unlock(&vfio.group_lock);
514
515 return group;
516}
517
518static struct vfio_group *vfio_group_get_from_dev(struct device *dev)
519{
520 struct iommu_group *iommu_group;
521 struct vfio_group *group;
522
523 iommu_group = iommu_group_get(dev);
524 if (!iommu_group)
525 return NULL;
526
527 group = vfio_group_get_from_iommu(iommu_group);
528 iommu_group_put(iommu_group);
529
530 return group;
531}
532
533/**
534 * Device objects - create, release, get, put, search
535 */
536static
537struct vfio_device *vfio_group_create_device(struct vfio_group *group,
538 struct device *dev,
539 const struct vfio_device_ops *ops,
540 void *device_data)
541{
542 struct vfio_device *device;
543
544 device = kzalloc(sizeof(*device), GFP_KERNEL);
545 if (!device)
546 return ERR_PTR(-ENOMEM);
547
548 kref_init(&device->kref);
549 device->dev = dev;
550 device->group = group;
551 device->ops = ops;
552 device->device_data = device_data;
553 dev_set_drvdata(dev, device);
554
555 /* No need to get group_lock, caller has group reference */
556 vfio_group_get(group);
557
558 mutex_lock(&group->device_lock);
559 list_add(&device->group_next, &group->device_list);
560 mutex_unlock(&group->device_lock);
561
562 return device;
563}
564
565static void vfio_device_release(struct kref *kref)
566{
567 struct vfio_device *device = container_of(kref,
568 struct vfio_device, kref);
569 struct vfio_group *group = device->group;
570
571 list_del(&device->group_next);
572 mutex_unlock(&group->device_lock);
573
574 dev_set_drvdata(device->dev, NULL);
575
576 kfree(device);
577
578 /* vfio_del_group_dev may be waiting for this device */
579 wake_up(&vfio.release_q);
580}
581
582/* Device reference always implies a group reference */
583void vfio_device_put(struct vfio_device *device)
584{
585 struct vfio_group *group = device->group;
586 kref_put_mutex(&device->kref, vfio_device_release, &group->device_lock);
587 vfio_group_put(group);
588}
589EXPORT_SYMBOL_GPL(vfio_device_put);
590
591static void vfio_device_get(struct vfio_device *device)
592{
593 vfio_group_get(device->group);
594 kref_get(&device->kref);
595}
596
597static struct vfio_device *vfio_group_get_device(struct vfio_group *group,
598 struct device *dev)
599{
600 struct vfio_device *device;
601
602 mutex_lock(&group->device_lock);
603 list_for_each_entry(device, &group->device_list, group_next) {
604 if (device->dev == dev) {
605 vfio_device_get(device);
606 mutex_unlock(&group->device_lock);
607 return device;
608 }
609 }
610 mutex_unlock(&group->device_lock);
611 return NULL;
612}
613
614/*
615 * Some drivers, like pci-stub, are only used to prevent other drivers from
616 * claiming a device and are therefore perfectly legitimate for a user owned
617 * group. The pci-stub driver has no dependencies on DMA or the IOVA mapping
618 * of the device, but it does prevent the user from having direct access to
619 * the device, which is useful in some circumstances.
620 *
621 * We also assume that we can include PCI interconnect devices, ie. bridges.
622 * IOMMU grouping on PCI necessitates that if we lack isolation on a bridge
623 * then all of the downstream devices will be part of the same IOMMU group as
624 * the bridge. Thus, if placing the bridge into the user owned IOVA space
625 * breaks anything, it only does so for user owned devices downstream. Note
626 * that error notification via MSI can be affected for platforms that handle
627 * MSI within the same IOVA space as DMA.
628 */
629static const char * const vfio_driver_whitelist[] = { "pci-stub" };
630
631static bool vfio_dev_whitelisted(struct device *dev, struct device_driver *drv)
632{
633 if (dev_is_pci(dev)) {
634 struct pci_dev *pdev = to_pci_dev(dev);
635
636 if (pdev->hdr_type != PCI_HEADER_TYPE_NORMAL)
637 return true;
638 }
639
640 return match_string(vfio_driver_whitelist,
641 ARRAY_SIZE(vfio_driver_whitelist),
642 drv->name) >= 0;
643}
644
645/*
646 * A vfio group is viable for use by userspace if all devices are in
647 * one of the following states:
648 * - driver-less
649 * - bound to a vfio driver
650 * - bound to a whitelisted driver
651 * - a PCI interconnect device
652 *
653 * We use two methods to determine whether a device is bound to a vfio
654 * driver. The first is to test whether the device exists in the vfio
655 * group. The second is to test if the device exists on the group
656 * unbound_list, indicating it's in the middle of transitioning from
657 * a vfio driver to driver-less.
658 */
659static int vfio_dev_viable(struct device *dev, void *data)
660{
661 struct vfio_group *group = data;
662 struct vfio_device *device;
663 struct device_driver *drv = READ_ONCE(dev->driver);
664 struct vfio_unbound_dev *unbound;
665 int ret = -EINVAL;
666
667 mutex_lock(&group->unbound_lock);
668 list_for_each_entry(unbound, &group->unbound_list, unbound_next) {
669 if (dev == unbound->dev) {
670 ret = 0;
671 break;
672 }
673 }
674 mutex_unlock(&group->unbound_lock);
675
676 if (!ret || !drv || vfio_dev_whitelisted(dev, drv))
677 return 0;
678
679 device = vfio_group_get_device(group, dev);
680 if (device) {
681 vfio_device_put(device);
682 return 0;
683 }
684
685 return ret;
686}
687
688/**
689 * Async device support
690 */
691static int vfio_group_nb_add_dev(struct vfio_group *group, struct device *dev)
692{
693 struct vfio_device *device;
694
695 /* Do we already know about it? We shouldn't */
696 device = vfio_group_get_device(group, dev);
697 if (WARN_ON_ONCE(device)) {
698 vfio_device_put(device);
699 return 0;
700 }
701
702 /* Nothing to do for idle groups */
703 if (!atomic_read(&group->container_users))
704 return 0;
705
706 /* TODO Prevent device auto probing */
707 WARN(1, "Device %s added to live group %d!\n", dev_name(dev),
708 iommu_group_id(group->iommu_group));
709
710 return 0;
711}
712
713static int vfio_group_nb_verify(struct vfio_group *group, struct device *dev)
714{
715 /* We don't care what happens when the group isn't in use */
716 if (!atomic_read(&group->container_users))
717 return 0;
718
719 return vfio_dev_viable(dev, group);
720}
721
722static int vfio_iommu_group_notifier(struct notifier_block *nb,
723 unsigned long action, void *data)
724{
725 struct vfio_group *group = container_of(nb, struct vfio_group, nb);
726 struct device *dev = data;
727 struct vfio_unbound_dev *unbound;
728
729 /*
730 * Need to go through a group_lock lookup to get a reference or we
731 * risk racing a group being removed. Ignore spurious notifies.
732 */
733 group = vfio_group_try_get(group);
734 if (!group)
735 return NOTIFY_OK;
736
737 switch (action) {
738 case IOMMU_GROUP_NOTIFY_ADD_DEVICE:
739 vfio_group_nb_add_dev(group, dev);
740 break;
741 case IOMMU_GROUP_NOTIFY_DEL_DEVICE:
742 /*
743 * Nothing to do here. If the device is in use, then the
744 * vfio sub-driver should block the remove callback until
745 * it is unused. If the device is unused or attached to a
746 * stub driver, then it should be released and we don't
747 * care that it will be going away.
748 */
749 break;
750 case IOMMU_GROUP_NOTIFY_BIND_DRIVER:
751 pr_debug("%s: Device %s, group %d binding to driver\n",
752 __func__, dev_name(dev),
753 iommu_group_id(group->iommu_group));
754 break;
755 case IOMMU_GROUP_NOTIFY_BOUND_DRIVER:
756 pr_debug("%s: Device %s, group %d bound to driver %s\n",
757 __func__, dev_name(dev),
758 iommu_group_id(group->iommu_group), dev->driver->name);
759 BUG_ON(vfio_group_nb_verify(group, dev));
760 break;
761 case IOMMU_GROUP_NOTIFY_UNBIND_DRIVER:
762 pr_debug("%s: Device %s, group %d unbinding from driver %s\n",
763 __func__, dev_name(dev),
764 iommu_group_id(group->iommu_group), dev->driver->name);
765 break;
766 case IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER:
767 pr_debug("%s: Device %s, group %d unbound from driver\n",
768 __func__, dev_name(dev),
769 iommu_group_id(group->iommu_group));
770 /*
771 * XXX An unbound device in a live group is ok, but we'd
772 * really like to avoid the above BUG_ON by preventing other
773 * drivers from binding to it. Once that occurs, we have to
774 * stop the system to maintain isolation. At a minimum, we'd
775 * want a toggle to disable driver auto probe for this device.
776 */
777
778 mutex_lock(&group->unbound_lock);
779 list_for_each_entry(unbound,
780 &group->unbound_list, unbound_next) {
781 if (dev == unbound->dev) {
782 list_del(&unbound->unbound_next);
783 kfree(unbound);
784 break;
785 }
786 }
787 mutex_unlock(&group->unbound_lock);
788 break;
789 }
790
791 /*
792 * If we're the last reference to the group, the group will be
793 * released, which includes unregistering the iommu group notifier.
794 * We hold a read-lock on that notifier list, unregistering needs
795 * a write-lock... deadlock. Release our reference asynchronously
796 * to avoid that situation.
797 */
798 vfio_group_schedule_put(group);
799 return NOTIFY_OK;
800}
801
802/**
803 * VFIO driver API
804 */
805int vfio_add_group_dev(struct device *dev,
806 const struct vfio_device_ops *ops, void *device_data)
807{
808 struct iommu_group *iommu_group;
809 struct vfio_group *group;
810 struct vfio_device *device;
811
812 iommu_group = iommu_group_get(dev);
813 if (!iommu_group)
814 return -EINVAL;
815
816 group = vfio_group_get_from_iommu(iommu_group);
817 if (!group) {
818 group = vfio_create_group(iommu_group);
819 if (IS_ERR(group)) {
820 iommu_group_put(iommu_group);
821 return PTR_ERR(group);
822 }
823 } else {
824 /*
825 * A found vfio_group already holds a reference to the
826 * iommu_group. A created vfio_group keeps the reference.
827 */
828 iommu_group_put(iommu_group);
829 }
830
831 device = vfio_group_get_device(group, dev);
832 if (device) {
833 WARN(1, "Device %s already exists on group %d\n",
834 dev_name(dev), iommu_group_id(iommu_group));
835 vfio_device_put(device);
836 vfio_group_put(group);
837 return -EBUSY;
838 }
839
840 device = vfio_group_create_device(group, dev, ops, device_data);
841 if (IS_ERR(device)) {
842 vfio_group_put(group);
843 return PTR_ERR(device);
844 }
845
846 /*
847 * Drop all but the vfio_device reference. The vfio_device holds
848 * a reference to the vfio_group, which holds a reference to the
849 * iommu_group.
850 */
851 vfio_group_put(group);
852
853 return 0;
854}
855EXPORT_SYMBOL_GPL(vfio_add_group_dev);
856
857/**
858 * Get a reference to the vfio_device for a device. Even if the
859 * caller thinks they own the device, they could be racing with a
860 * release call path, so we can't trust drvdata for the shortcut.
861 * Go the long way around, from the iommu_group to the vfio_group
862 * to the vfio_device.
863 */
864struct vfio_device *vfio_device_get_from_dev(struct device *dev)
865{
866 struct vfio_group *group;
867 struct vfio_device *device;
868
869 group = vfio_group_get_from_dev(dev);
870 if (!group)
871 return NULL;
872
873 device = vfio_group_get_device(group, dev);
874 vfio_group_put(group);
875
876 return device;
877}
878EXPORT_SYMBOL_GPL(vfio_device_get_from_dev);
879
880static struct vfio_device *vfio_device_get_from_name(struct vfio_group *group,
881 char *buf)
882{
883 struct vfio_device *it, *device = NULL;
884
885 mutex_lock(&group->device_lock);
886 list_for_each_entry(it, &group->device_list, group_next) {
887 if (!strcmp(dev_name(it->dev), buf)) {
888 device = it;
889 vfio_device_get(device);
890 break;
891 }
892 }
893 mutex_unlock(&group->device_lock);
894
895 return device;
896}
897
898/*
899 * Caller must hold a reference to the vfio_device
900 */
901void *vfio_device_data(struct vfio_device *device)
902{
903 return device->device_data;
904}
905EXPORT_SYMBOL_GPL(vfio_device_data);
906
907/* Given a referenced group, check if it contains the device */
908static bool vfio_dev_present(struct vfio_group *group, struct device *dev)
909{
910 struct vfio_device *device;
911
912 device = vfio_group_get_device(group, dev);
913 if (!device)
914 return false;
915
916 vfio_device_put(device);
917 return true;
918}
919
920/*
921 * Decrement the device reference count and wait for the device to be
922 * removed. Open file descriptors for the device... */
923void *vfio_del_group_dev(struct device *dev)
924{
925 struct vfio_device *device = dev_get_drvdata(dev);
926 struct vfio_group *group = device->group;
927 void *device_data = device->device_data;
928 struct vfio_unbound_dev *unbound;
929 unsigned int i = 0;
930 long ret;
931 bool interrupted = false;
932
933 /*
934 * The group exists so long as we have a device reference. Get
935 * a group reference and use it to scan for the device going away.
936 */
937 vfio_group_get(group);
938
939 /*
940 * When the device is removed from the group, the group suddenly
941 * becomes non-viable; the device has a driver (until the unbind
942 * completes), but it's not present in the group. This is bad news
943 * for any external users that need to re-acquire a group reference
944 * in order to match and release their existing reference. To
945 * solve this, we track such devices on the unbound_list to bridge
946 * the gap until they're fully unbound.
947 */
948 unbound = kzalloc(sizeof(*unbound), GFP_KERNEL);
949 if (unbound) {
950 unbound->dev = dev;
951 mutex_lock(&group->unbound_lock);
952 list_add(&unbound->unbound_next, &group->unbound_list);
953 mutex_unlock(&group->unbound_lock);
954 }
955 WARN_ON(!unbound);
956
957 vfio_device_put(device);
958
959 /*
960 * If the device is still present in the group after the above
961 * 'put', then it is in use and we need to request it from the
962 * bus driver. The driver may in turn need to request the
963 * device from the user. We send the request on an arbitrary
964 * interval with counter to allow the driver to take escalating
965 * measures to release the device if it has the ability to do so.
966 */
967 do {
968 device = vfio_group_get_device(group, dev);
969 if (!device)
970 break;
971
972 if (device->ops->request)
973 device->ops->request(device_data, i++);
974
975 vfio_device_put(device);
976
977 if (interrupted) {
978 ret = wait_event_timeout(vfio.release_q,
979 !vfio_dev_present(group, dev), HZ * 10);
980 } else {
981 ret = wait_event_interruptible_timeout(vfio.release_q,
982 !vfio_dev_present(group, dev), HZ * 10);
983 if (ret == -ERESTARTSYS) {
984 interrupted = true;
985 dev_warn(dev,
986 "Device is currently in use, task"
987 " \"%s\" (%d) "
988 "blocked until device is released",
989 current->comm, task_pid_nr(current));
990 }
991 }
992 } while (ret <= 0);
993
994 /*
995 * In order to support multiple devices per group, devices can be
996 * plucked from the group while other devices in the group are still
997 * in use. The container persists with this group and those remaining
998 * devices still attached. If the user creates an isolation violation
999 * by binding this device to another driver while the group is still in
1000 * use, that's their fault. However, in the case of removing the last,
1001 * or potentially the only, device in the group there can be no other
1002 * in-use devices in the group. The user has done their due diligence
1003 * and we should lay no claims to those devices. In order to do that,
1004 * we need to make sure the group is detached from the container.
1005 * Without this stall, we're potentially racing with a user process
1006 * that may attempt to immediately bind this device to another driver.
1007 */
1008 if (list_empty(&group->device_list))
1009 wait_event(group->container_q, !group->container);
1010
1011 vfio_group_put(group);
1012
1013 return device_data;
1014}
1015EXPORT_SYMBOL_GPL(vfio_del_group_dev);
1016
1017/**
1018 * VFIO base fd, /dev/vfio/vfio
1019 */
1020static long vfio_ioctl_check_extension(struct vfio_container *container,
1021 unsigned long arg)
1022{
1023 struct vfio_iommu_driver *driver;
1024 long ret = 0;
1025
1026 down_read(&container->group_lock);
1027
1028 driver = container->iommu_driver;
1029
1030 switch (arg) {
1031 /* No base extensions yet */
1032 default:
1033 /*
1034 * If no driver is set, poll all registered drivers for
1035 * extensions and return the first positive result. If
1036 * a driver is already set, further queries will be passed
1037 * only to that driver.
1038 */
1039 if (!driver) {
1040 mutex_lock(&vfio.iommu_drivers_lock);
1041 list_for_each_entry(driver, &vfio.iommu_drivers_list,
1042 vfio_next) {
1043
1044#ifdef CONFIG_VFIO_NOIOMMU
1045 if (!list_empty(&container->group_list) &&
1046 (container->noiommu !=
1047 (driver->ops == &vfio_noiommu_ops)))
1048 continue;
1049#endif
1050
1051 if (!try_module_get(driver->ops->owner))
1052 continue;
1053
1054 ret = driver->ops->ioctl(NULL,
1055 VFIO_CHECK_EXTENSION,
1056 arg);
1057 module_put(driver->ops->owner);
1058 if (ret > 0)
1059 break;
1060 }
1061 mutex_unlock(&vfio.iommu_drivers_lock);
1062 } else
1063 ret = driver->ops->ioctl(container->iommu_data,
1064 VFIO_CHECK_EXTENSION, arg);
1065 }
1066
1067 up_read(&container->group_lock);
1068
1069 return ret;
1070}
1071
1072/* hold write lock on container->group_lock */
1073static int __vfio_container_attach_groups(struct vfio_container *container,
1074 struct vfio_iommu_driver *driver,
1075 void *data)
1076{
1077 struct vfio_group *group;
1078 int ret = -ENODEV;
1079
1080 list_for_each_entry(group, &container->group_list, container_next) {
1081 ret = driver->ops->attach_group(data, group->iommu_group);
1082 if (ret)
1083 goto unwind;
1084 }
1085
1086 return ret;
1087
1088unwind:
1089 list_for_each_entry_continue_reverse(group, &container->group_list,
1090 container_next) {
1091 driver->ops->detach_group(data, group->iommu_group);
1092 }
1093
1094 return ret;
1095}
1096
1097static long vfio_ioctl_set_iommu(struct vfio_container *container,
1098 unsigned long arg)
1099{
1100 struct vfio_iommu_driver *driver;
1101 long ret = -ENODEV;
1102
1103 down_write(&container->group_lock);
1104
1105 /*
1106 * The container is designed to be an unprivileged interface while
1107 * the group can be assigned to specific users. Therefore, only by
1108 * adding a group to a container does the user get the privilege of
1109 * enabling the iommu, which may allocate finite resources. There
1110 * is no unset_iommu, but by removing all the groups from a container,
1111 * the container is deprivileged and returns to an unset state.
1112 */
1113 if (list_empty(&container->group_list) || container->iommu_driver) {
1114 up_write(&container->group_lock);
1115 return -EINVAL;
1116 }
1117
1118 mutex_lock(&vfio.iommu_drivers_lock);
1119 list_for_each_entry(driver, &vfio.iommu_drivers_list, vfio_next) {
1120 void *data;
1121
1122#ifdef CONFIG_VFIO_NOIOMMU
1123 /*
1124 * Only noiommu containers can use vfio-noiommu and noiommu
1125 * containers can only use vfio-noiommu.
1126 */
1127 if (container->noiommu != (driver->ops == &vfio_noiommu_ops))
1128 continue;
1129#endif
1130
1131 if (!try_module_get(driver->ops->owner))
1132 continue;
1133
1134 /*
1135 * The arg magic for SET_IOMMU is the same as CHECK_EXTENSION,
1136 * so test which iommu driver reported support for this
1137 * extension and call open on them. We also pass them the
1138 * magic, allowing a single driver to support multiple
1139 * interfaces if they'd like.
1140 */
1141 if (driver->ops->ioctl(NULL, VFIO_CHECK_EXTENSION, arg) <= 0) {
1142 module_put(driver->ops->owner);
1143 continue;
1144 }
1145
1146 data = driver->ops->open(arg);
1147 if (IS_ERR(data)) {
1148 ret = PTR_ERR(data);
1149 module_put(driver->ops->owner);
1150 continue;
1151 }
1152
1153 ret = __vfio_container_attach_groups(container, driver, data);
1154 if (ret) {
1155 driver->ops->release(data);
1156 module_put(driver->ops->owner);
1157 continue;
1158 }
1159
1160 container->iommu_driver = driver;
1161 container->iommu_data = data;
1162 break;
1163 }
1164
1165 mutex_unlock(&vfio.iommu_drivers_lock);
1166 up_write(&container->group_lock);
1167
1168 return ret;
1169}
1170
1171static long vfio_fops_unl_ioctl(struct file *filep,
1172 unsigned int cmd, unsigned long arg)
1173{
1174 struct vfio_container *container = filep->private_data;
1175 struct vfio_iommu_driver *driver;
1176 void *data;
1177 long ret = -EINVAL;
1178
1179 if (!container)
1180 return ret;
1181
1182 switch (cmd) {
1183 case VFIO_GET_API_VERSION:
1184 ret = VFIO_API_VERSION;
1185 break;
1186 case VFIO_CHECK_EXTENSION:
1187 ret = vfio_ioctl_check_extension(container, arg);
1188 break;
1189 case VFIO_SET_IOMMU:
1190 ret = vfio_ioctl_set_iommu(container, arg);
1191 break;
1192 default:
1193 driver = container->iommu_driver;
1194 data = container->iommu_data;
1195
1196 if (driver) /* passthrough all unrecognized ioctls */
1197 ret = driver->ops->ioctl(data, cmd, arg);
1198 }
1199
1200 return ret;
1201}
1202
1203#ifdef CONFIG_COMPAT
1204static long vfio_fops_compat_ioctl(struct file *filep,
1205 unsigned int cmd, unsigned long arg)
1206{
1207 arg = (unsigned long)compat_ptr(arg);
1208 return vfio_fops_unl_ioctl(filep, cmd, arg);
1209}
1210#endif /* CONFIG_COMPAT */
1211
1212static int vfio_fops_open(struct inode *inode, struct file *filep)
1213{
1214 struct vfio_container *container;
1215
1216 container = kzalloc(sizeof(*container), GFP_KERNEL);
1217 if (!container)
1218 return -ENOMEM;
1219
1220 INIT_LIST_HEAD(&container->group_list);
1221 init_rwsem(&container->group_lock);
1222 kref_init(&container->kref);
1223
1224 filep->private_data = container;
1225
1226 return 0;
1227}
1228
1229static int vfio_fops_release(struct inode *inode, struct file *filep)
1230{
1231 struct vfio_container *container = filep->private_data;
1232
1233 filep->private_data = NULL;
1234
1235 vfio_container_put(container);
1236
1237 return 0;
1238}
1239
1240/*
1241 * Once an iommu driver is set, we optionally pass read/write/mmap
1242 * on to the driver, allowing management interfaces beyond ioctl.
1243 */
1244static ssize_t vfio_fops_read(struct file *filep, char __user *buf,
1245 size_t count, loff_t *ppos)
1246{
1247 struct vfio_container *container = filep->private_data;
1248 struct vfio_iommu_driver *driver;
1249 ssize_t ret = -EINVAL;
1250
1251 driver = container->iommu_driver;
1252 if (likely(driver && driver->ops->read))
1253 ret = driver->ops->read(container->iommu_data,
1254 buf, count, ppos);
1255
1256 return ret;
1257}
1258
1259static ssize_t vfio_fops_write(struct file *filep, const char __user *buf,
1260 size_t count, loff_t *ppos)
1261{
1262 struct vfio_container *container = filep->private_data;
1263 struct vfio_iommu_driver *driver;
1264 ssize_t ret = -EINVAL;
1265
1266 driver = container->iommu_driver;
1267 if (likely(driver && driver->ops->write))
1268 ret = driver->ops->write(container->iommu_data,
1269 buf, count, ppos);
1270
1271 return ret;
1272}
1273
1274static int vfio_fops_mmap(struct file *filep, struct vm_area_struct *vma)
1275{
1276 struct vfio_container *container = filep->private_data;
1277 struct vfio_iommu_driver *driver;
1278 int ret = -EINVAL;
1279
1280 driver = container->iommu_driver;
1281 if (likely(driver && driver->ops->mmap))
1282 ret = driver->ops->mmap(container->iommu_data, vma);
1283
1284 return ret;
1285}
1286
1287static const struct file_operations vfio_fops = {
1288 .owner = THIS_MODULE,
1289 .open = vfio_fops_open,
1290 .release = vfio_fops_release,
1291 .read = vfio_fops_read,
1292 .write = vfio_fops_write,
1293 .unlocked_ioctl = vfio_fops_unl_ioctl,
1294#ifdef CONFIG_COMPAT
1295 .compat_ioctl = vfio_fops_compat_ioctl,
1296#endif
1297 .mmap = vfio_fops_mmap,
1298};
1299
1300/**
1301 * VFIO Group fd, /dev/vfio/$GROUP
1302 */
1303static void __vfio_group_unset_container(struct vfio_group *group)
1304{
1305 struct vfio_container *container = group->container;
1306 struct vfio_iommu_driver *driver;
1307
1308 down_write(&container->group_lock);
1309
1310 driver = container->iommu_driver;
1311 if (driver)
1312 driver->ops->detach_group(container->iommu_data,
1313 group->iommu_group);
1314
1315 group->container = NULL;
1316 wake_up(&group->container_q);
1317 list_del(&group->container_next);
1318
1319 /* Detaching the last group deprivileges a container, remove iommu */
1320 if (driver && list_empty(&container->group_list)) {
1321 driver->ops->release(container->iommu_data);
1322 module_put(driver->ops->owner);
1323 container->iommu_driver = NULL;
1324 container->iommu_data = NULL;
1325 }
1326
1327 up_write(&container->group_lock);
1328
1329 vfio_container_put(container);
1330}
1331
1332/*
1333 * VFIO_GROUP_UNSET_CONTAINER should fail if there are other users or
1334 * if there was no container to unset. Since the ioctl is called on
1335 * the group, we know that still exists, therefore the only valid
1336 * transition here is 1->0.
1337 */
1338static int vfio_group_unset_container(struct vfio_group *group)
1339{
1340 int users = atomic_cmpxchg(&group->container_users, 1, 0);
1341
1342 if (!users)
1343 return -EINVAL;
1344 if (users != 1)
1345 return -EBUSY;
1346
1347 __vfio_group_unset_container(group);
1348
1349 return 0;
1350}
1351
1352/*
1353 * When removing container users, anything that removes the last user
1354 * implicitly removes the group from the container. That is, if the
1355 * group file descriptor is closed, as well as any device file descriptors,
1356 * the group is free.
1357 */
1358static void vfio_group_try_dissolve_container(struct vfio_group *group)
1359{
1360 if (0 == atomic_dec_if_positive(&group->container_users))
1361 __vfio_group_unset_container(group);
1362}
1363
1364static int vfio_group_set_container(struct vfio_group *group, int container_fd)
1365{
1366 struct fd f;
1367 struct vfio_container *container;
1368 struct vfio_iommu_driver *driver;
1369 int ret = 0;
1370
1371 if (atomic_read(&group->container_users))
1372 return -EINVAL;
1373
1374 if (group->noiommu && !capable(CAP_SYS_RAWIO))
1375 return -EPERM;
1376
1377 f = fdget(container_fd);
1378 if (!f.file)
1379 return -EBADF;
1380
1381 /* Sanity check, is this really our fd? */
1382 if (f.file->f_op != &vfio_fops) {
1383 fdput(f);
1384 return -EINVAL;
1385 }
1386
1387 container = f.file->private_data;
1388 WARN_ON(!container); /* fget ensures we don't race vfio_release */
1389
1390 down_write(&container->group_lock);
1391
1392 /* Real groups and fake groups cannot mix */
1393 if (!list_empty(&container->group_list) &&
1394 container->noiommu != group->noiommu) {
1395 ret = -EPERM;
1396 goto unlock_out;
1397 }
1398
1399 driver = container->iommu_driver;
1400 if (driver) {
1401 ret = driver->ops->attach_group(container->iommu_data,
1402 group->iommu_group);
1403 if (ret)
1404 goto unlock_out;
1405 }
1406
1407 group->container = container;
1408 container->noiommu = group->noiommu;
1409 list_add(&group->container_next, &container->group_list);
1410
1411 /* Get a reference on the container and mark a user within the group */
1412 vfio_container_get(container);
1413 atomic_inc(&group->container_users);
1414
1415unlock_out:
1416 up_write(&container->group_lock);
1417 fdput(f);
1418 return ret;
1419}
1420
1421static bool vfio_group_viable(struct vfio_group *group)
1422{
1423 return (iommu_group_for_each_dev(group->iommu_group,
1424 group, vfio_dev_viable) == 0);
1425}
1426
1427static int vfio_group_add_container_user(struct vfio_group *group)
1428{
1429 if (!atomic_inc_not_zero(&group->container_users))
1430 return -EINVAL;
1431
1432 if (group->noiommu) {
1433 atomic_dec(&group->container_users);
1434 return -EPERM;
1435 }
1436 if (!group->container->iommu_driver || !vfio_group_viable(group)) {
1437 atomic_dec(&group->container_users);
1438 return -EINVAL;
1439 }
1440
1441 return 0;
1442}
1443
1444static const struct file_operations vfio_device_fops;
1445
1446static int vfio_group_get_device_fd(struct vfio_group *group, char *buf)
1447{
1448 struct vfio_device *device;
1449 struct file *filep;
1450 int ret;
1451
1452 if (0 == atomic_read(&group->container_users) ||
1453 !group->container->iommu_driver || !vfio_group_viable(group))
1454 return -EINVAL;
1455
1456 if (group->noiommu && !capable(CAP_SYS_RAWIO))
1457 return -EPERM;
1458
1459 device = vfio_device_get_from_name(group, buf);
1460 if (!device)
1461 return -ENODEV;
1462
1463 ret = device->ops->open(device->device_data);
1464 if (ret) {
1465 vfio_device_put(device);
1466 return ret;
1467 }
1468
1469 /*
1470 * We can't use anon_inode_getfd() because we need to modify
1471 * the f_mode flags directly to allow more than just ioctls
1472 */
1473 ret = get_unused_fd_flags(O_CLOEXEC);
1474 if (ret < 0) {
1475 device->ops->release(device->device_data);
1476 vfio_device_put(device);
1477 return ret;
1478 }
1479
1480 filep = anon_inode_getfile("[vfio-device]", &vfio_device_fops,
1481 device, O_RDWR);
1482 if (IS_ERR(filep)) {
1483 put_unused_fd(ret);
1484 ret = PTR_ERR(filep);
1485 device->ops->release(device->device_data);
1486 vfio_device_put(device);
1487 return ret;
1488 }
1489
1490 /*
1491 * TODO: add an anon_inode interface to do this.
1492 * Appears to be missing by lack of need rather than
1493 * explicitly prevented. Now there's need.
1494 */
1495 filep->f_mode |= (FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE);
1496
1497 atomic_inc(&group->container_users);
1498
1499 fd_install(ret, filep);
1500
1501 if (group->noiommu)
1502 dev_warn(device->dev, "vfio-noiommu device opened by user "
1503 "(%s:%d)\n", current->comm, task_pid_nr(current));
1504
1505 return ret;
1506}
1507
1508static long vfio_group_fops_unl_ioctl(struct file *filep,
1509 unsigned int cmd, unsigned long arg)
1510{
1511 struct vfio_group *group = filep->private_data;
1512 long ret = -ENOTTY;
1513
1514 switch (cmd) {
1515 case VFIO_GROUP_GET_STATUS:
1516 {
1517 struct vfio_group_status status;
1518 unsigned long minsz;
1519
1520 minsz = offsetofend(struct vfio_group_status, flags);
1521
1522 if (copy_from_user(&status, (void __user *)arg, minsz))
1523 return -EFAULT;
1524
1525 if (status.argsz < minsz)
1526 return -EINVAL;
1527
1528 status.flags = 0;
1529
1530 if (vfio_group_viable(group))
1531 status.flags |= VFIO_GROUP_FLAGS_VIABLE;
1532
1533 if (group->container)
1534 status.flags |= VFIO_GROUP_FLAGS_CONTAINER_SET;
1535
1536 if (copy_to_user((void __user *)arg, &status, minsz))
1537 return -EFAULT;
1538
1539 ret = 0;
1540 break;
1541 }
1542 case VFIO_GROUP_SET_CONTAINER:
1543 {
1544 int fd;
1545
1546 if (get_user(fd, (int __user *)arg))
1547 return -EFAULT;
1548
1549 if (fd < 0)
1550 return -EINVAL;
1551
1552 ret = vfio_group_set_container(group, fd);
1553 break;
1554 }
1555 case VFIO_GROUP_UNSET_CONTAINER:
1556 ret = vfio_group_unset_container(group);
1557 break;
1558 case VFIO_GROUP_GET_DEVICE_FD:
1559 {
1560 char *buf;
1561
1562 buf = strndup_user((const char __user *)arg, PAGE_SIZE);
1563 if (IS_ERR(buf))
1564 return PTR_ERR(buf);
1565
1566 ret = vfio_group_get_device_fd(group, buf);
1567 kfree(buf);
1568 break;
1569 }
1570 }
1571
1572 return ret;
1573}
1574
1575#ifdef CONFIG_COMPAT
1576static long vfio_group_fops_compat_ioctl(struct file *filep,
1577 unsigned int cmd, unsigned long arg)
1578{
1579 arg = (unsigned long)compat_ptr(arg);
1580 return vfio_group_fops_unl_ioctl(filep, cmd, arg);
1581}
1582#endif /* CONFIG_COMPAT */
1583
1584static int vfio_group_fops_open(struct inode *inode, struct file *filep)
1585{
1586 struct vfio_group *group;
1587 int opened;
1588
1589 group = vfio_group_get_from_minor(iminor(inode));
1590 if (!group)
1591 return -ENODEV;
1592
1593 if (group->noiommu && !capable(CAP_SYS_RAWIO)) {
1594 vfio_group_put(group);
1595 return -EPERM;
1596 }
1597
1598 /* Do we need multiple instances of the group open? Seems not. */
1599 opened = atomic_cmpxchg(&group->opened, 0, 1);
1600 if (opened) {
1601 vfio_group_put(group);
1602 return -EBUSY;
1603 }
1604
1605 /* Is something still in use from a previous open? */
1606 if (group->container) {
1607 atomic_dec(&group->opened);
1608 vfio_group_put(group);
1609 return -EBUSY;
1610 }
1611
1612 /* Warn if previous user didn't cleanup and re-init to drop them */
1613 if (WARN_ON(group->notifier.head))
1614 BLOCKING_INIT_NOTIFIER_HEAD(&group->notifier);
1615
1616 filep->private_data = group;
1617
1618 return 0;
1619}
1620
1621static int vfio_group_fops_release(struct inode *inode, struct file *filep)
1622{
1623 struct vfio_group *group = filep->private_data;
1624
1625 filep->private_data = NULL;
1626
1627 vfio_group_try_dissolve_container(group);
1628
1629 atomic_dec(&group->opened);
1630
1631 vfio_group_put(group);
1632
1633 return 0;
1634}
1635
1636static const struct file_operations vfio_group_fops = {
1637 .owner = THIS_MODULE,
1638 .unlocked_ioctl = vfio_group_fops_unl_ioctl,
1639#ifdef CONFIG_COMPAT
1640 .compat_ioctl = vfio_group_fops_compat_ioctl,
1641#endif
1642 .open = vfio_group_fops_open,
1643 .release = vfio_group_fops_release,
1644};
1645
1646/**
1647 * VFIO Device fd
1648 */
1649static int vfio_device_fops_release(struct inode *inode, struct file *filep)
1650{
1651 struct vfio_device *device = filep->private_data;
1652
1653 device->ops->release(device->device_data);
1654
1655 vfio_group_try_dissolve_container(device->group);
1656
1657 vfio_device_put(device);
1658
1659 return 0;
1660}
1661
1662static long vfio_device_fops_unl_ioctl(struct file *filep,
1663 unsigned int cmd, unsigned long arg)
1664{
1665 struct vfio_device *device = filep->private_data;
1666
1667 if (unlikely(!device->ops->ioctl))
1668 return -EINVAL;
1669
1670 return device->ops->ioctl(device->device_data, cmd, arg);
1671}
1672
1673static ssize_t vfio_device_fops_read(struct file *filep, char __user *buf,
1674 size_t count, loff_t *ppos)
1675{
1676 struct vfio_device *device = filep->private_data;
1677
1678 if (unlikely(!device->ops->read))
1679 return -EINVAL;
1680
1681 return device->ops->read(device->device_data, buf, count, ppos);
1682}
1683
1684static ssize_t vfio_device_fops_write(struct file *filep,
1685 const char __user *buf,
1686 size_t count, loff_t *ppos)
1687{
1688 struct vfio_device *device = filep->private_data;
1689
1690 if (unlikely(!device->ops->write))
1691 return -EINVAL;
1692
1693 return device->ops->write(device->device_data, buf, count, ppos);
1694}
1695
1696static int vfio_device_fops_mmap(struct file *filep, struct vm_area_struct *vma)
1697{
1698 struct vfio_device *device = filep->private_data;
1699
1700 if (unlikely(!device->ops->mmap))
1701 return -EINVAL;
1702
1703 return device->ops->mmap(device->device_data, vma);
1704}
1705
1706#ifdef CONFIG_COMPAT
1707static long vfio_device_fops_compat_ioctl(struct file *filep,
1708 unsigned int cmd, unsigned long arg)
1709{
1710 arg = (unsigned long)compat_ptr(arg);
1711 return vfio_device_fops_unl_ioctl(filep, cmd, arg);
1712}
1713#endif /* CONFIG_COMPAT */
1714
1715static const struct file_operations vfio_device_fops = {
1716 .owner = THIS_MODULE,
1717 .release = vfio_device_fops_release,
1718 .read = vfio_device_fops_read,
1719 .write = vfio_device_fops_write,
1720 .unlocked_ioctl = vfio_device_fops_unl_ioctl,
1721#ifdef CONFIG_COMPAT
1722 .compat_ioctl = vfio_device_fops_compat_ioctl,
1723#endif
1724 .mmap = vfio_device_fops_mmap,
1725};
1726
1727/**
1728 * External user API, exported by symbols to be linked dynamically.
1729 *
1730 * The protocol includes:
1731 * 1. do normal VFIO init operation:
1732 * - opening a new container;
1733 * - attaching group(s) to it;
1734 * - setting an IOMMU driver for a container.
1735 * When IOMMU is set for a container, all groups in it are
1736 * considered ready to use by an external user.
1737 *
1738 * 2. User space passes a group fd to an external user.
1739 * The external user calls vfio_group_get_external_user()
1740 * to verify that:
1741 * - the group is initialized;
1742 * - IOMMU is set for it.
1743 * If both checks passed, vfio_group_get_external_user()
1744 * increments the container user counter to prevent
1745 * the VFIO group from disposal before KVM exits.
1746 *
1747 * 3. The external user calls vfio_external_user_iommu_id()
1748 * to know an IOMMU ID.
1749 *
1750 * 4. When the external KVM finishes, it calls
1751 * vfio_group_put_external_user() to release the VFIO group.
1752 * This call decrements the container user counter.
1753 */
1754struct vfio_group *vfio_group_get_external_user(struct file *filep)
1755{
1756 struct vfio_group *group = filep->private_data;
1757 int ret;
1758
1759 if (filep->f_op != &vfio_group_fops)
1760 return ERR_PTR(-EINVAL);
1761
1762 ret = vfio_group_add_container_user(group);
1763 if (ret)
1764 return ERR_PTR(ret);
1765
1766 vfio_group_get(group);
1767
1768 return group;
1769}
1770EXPORT_SYMBOL_GPL(vfio_group_get_external_user);
1771
1772void vfio_group_put_external_user(struct vfio_group *group)
1773{
1774 vfio_group_try_dissolve_container(group);
1775 vfio_group_put(group);
1776}
1777EXPORT_SYMBOL_GPL(vfio_group_put_external_user);
1778
1779bool vfio_external_group_match_file(struct vfio_group *test_group,
1780 struct file *filep)
1781{
1782 struct vfio_group *group = filep->private_data;
1783
1784 return (filep->f_op == &vfio_group_fops) && (group == test_group);
1785}
1786EXPORT_SYMBOL_GPL(vfio_external_group_match_file);
1787
1788int vfio_external_user_iommu_id(struct vfio_group *group)
1789{
1790 return iommu_group_id(group->iommu_group);
1791}
1792EXPORT_SYMBOL_GPL(vfio_external_user_iommu_id);
1793
1794long vfio_external_check_extension(struct vfio_group *group, unsigned long arg)
1795{
1796 return vfio_ioctl_check_extension(group->container, arg);
1797}
1798EXPORT_SYMBOL_GPL(vfio_external_check_extension);
1799
1800/**
1801 * Sub-module support
1802 */
1803/*
1804 * Helper for managing a buffer of info chain capabilities, allocate or
1805 * reallocate a buffer with additional @size, filling in @id and @version
1806 * of the capability. A pointer to the new capability is returned.
1807 *
1808 * NB. The chain is based at the head of the buffer, so new entries are
1809 * added to the tail, vfio_info_cap_shift() should be called to fixup the
1810 * next offsets prior to copying to the user buffer.
1811 */
1812struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps,
1813 size_t size, u16 id, u16 version)
1814{
1815 void *buf;
1816 struct vfio_info_cap_header *header, *tmp;
1817
1818 buf = krealloc(caps->buf, caps->size + size, GFP_KERNEL);
1819 if (!buf) {
1820 kfree(caps->buf);
1821 caps->size = 0;
1822 return ERR_PTR(-ENOMEM);
1823 }
1824
1825 caps->buf = buf;
1826 header = buf + caps->size;
1827
1828 /* Eventually copied to user buffer, zero */
1829 memset(header, 0, size);
1830
1831 header->id = id;
1832 header->version = version;
1833
1834 /* Add to the end of the capability chain */
1835 for (tmp = buf; tmp->next; tmp = buf + tmp->next)
1836 ; /* nothing */
1837
1838 tmp->next = caps->size;
1839 caps->size += size;
1840
1841 return header;
1842}
1843EXPORT_SYMBOL_GPL(vfio_info_cap_add);
1844
1845void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset)
1846{
1847 struct vfio_info_cap_header *tmp;
1848 void *buf = (void *)caps->buf;
1849
1850 for (tmp = buf; tmp->next; tmp = buf + tmp->next - offset)
1851 tmp->next += offset;
1852}
1853EXPORT_SYMBOL(vfio_info_cap_shift);
1854
1855int vfio_info_add_capability(struct vfio_info_cap *caps,
1856 struct vfio_info_cap_header *cap, size_t size)
1857{
1858 struct vfio_info_cap_header *header;
1859
1860 header = vfio_info_cap_add(caps, size, cap->id, cap->version);
1861 if (IS_ERR(header))
1862 return PTR_ERR(header);
1863
1864 memcpy(header + 1, cap + 1, size - sizeof(*header));
1865
1866 return 0;
1867}
1868EXPORT_SYMBOL(vfio_info_add_capability);
1869
1870int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr, int num_irqs,
1871 int max_irq_type, size_t *data_size)
1872{
1873 unsigned long minsz;
1874 size_t size;
1875
1876 minsz = offsetofend(struct vfio_irq_set, count);
1877
1878 if ((hdr->argsz < minsz) || (hdr->index >= max_irq_type) ||
1879 (hdr->count >= (U32_MAX - hdr->start)) ||
1880 (hdr->flags & ~(VFIO_IRQ_SET_DATA_TYPE_MASK |
1881 VFIO_IRQ_SET_ACTION_TYPE_MASK)))
1882 return -EINVAL;
1883
1884 if (data_size)
1885 *data_size = 0;
1886
1887 if (hdr->start >= num_irqs || hdr->start + hdr->count > num_irqs)
1888 return -EINVAL;
1889
1890 switch (hdr->flags & VFIO_IRQ_SET_DATA_TYPE_MASK) {
1891 case VFIO_IRQ_SET_DATA_NONE:
1892 size = 0;
1893 break;
1894 case VFIO_IRQ_SET_DATA_BOOL:
1895 size = sizeof(uint8_t);
1896 break;
1897 case VFIO_IRQ_SET_DATA_EVENTFD:
1898 size = sizeof(int32_t);
1899 break;
1900 default:
1901 return -EINVAL;
1902 }
1903
1904 if (size) {
1905 if (hdr->argsz - minsz < hdr->count * size)
1906 return -EINVAL;
1907
1908 if (!data_size)
1909 return -EINVAL;
1910
1911 *data_size = hdr->count * size;
1912 }
1913
1914 return 0;
1915}
1916EXPORT_SYMBOL(vfio_set_irqs_validate_and_prepare);
1917
1918/*
1919 * Pin a set of guest PFNs and return their associated host PFNs for local
1920 * domain only.
1921 * @dev [in] : device
1922 * @user_pfn [in]: array of user/guest PFNs to be pinned.
1923 * @npage [in] : count of elements in user_pfn array. This count should not
1924 * be greater VFIO_PIN_PAGES_MAX_ENTRIES.
1925 * @prot [in] : protection flags
1926 * @phys_pfn[out]: array of host PFNs
1927 * Return error or number of pages pinned.
1928 */
1929int vfio_pin_pages(struct device *dev, unsigned long *user_pfn, int npage,
1930 int prot, unsigned long *phys_pfn)
1931{
1932 struct vfio_container *container;
1933 struct vfio_group *group;
1934 struct vfio_iommu_driver *driver;
1935 int ret;
1936
1937 if (!dev || !user_pfn || !phys_pfn || !npage)
1938 return -EINVAL;
1939
1940 if (npage > VFIO_PIN_PAGES_MAX_ENTRIES)
1941 return -E2BIG;
1942
1943 group = vfio_group_get_from_dev(dev);
1944 if (!group)
1945 return -ENODEV;
1946
1947 ret = vfio_group_add_container_user(group);
1948 if (ret)
1949 goto err_pin_pages;
1950
1951 container = group->container;
1952 driver = container->iommu_driver;
1953 if (likely(driver && driver->ops->pin_pages))
1954 ret = driver->ops->pin_pages(container->iommu_data, user_pfn,
1955 npage, prot, phys_pfn);
1956 else
1957 ret = -ENOTTY;
1958
1959 vfio_group_try_dissolve_container(group);
1960
1961err_pin_pages:
1962 vfio_group_put(group);
1963 return ret;
1964}
1965EXPORT_SYMBOL(vfio_pin_pages);
1966
1967/*
1968 * Unpin set of host PFNs for local domain only.
1969 * @dev [in] : device
1970 * @user_pfn [in]: array of user/guest PFNs to be unpinned. Number of user/guest
1971 * PFNs should not be greater than VFIO_PIN_PAGES_MAX_ENTRIES.
1972 * @npage [in] : count of elements in user_pfn array. This count should not
1973 * be greater than VFIO_PIN_PAGES_MAX_ENTRIES.
1974 * Return error or number of pages unpinned.
1975 */
1976int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn, int npage)
1977{
1978 struct vfio_container *container;
1979 struct vfio_group *group;
1980 struct vfio_iommu_driver *driver;
1981 int ret;
1982
1983 if (!dev || !user_pfn || !npage)
1984 return -EINVAL;
1985
1986 if (npage > VFIO_PIN_PAGES_MAX_ENTRIES)
1987 return -E2BIG;
1988
1989 group = vfio_group_get_from_dev(dev);
1990 if (!group)
1991 return -ENODEV;
1992
1993 ret = vfio_group_add_container_user(group);
1994 if (ret)
1995 goto err_unpin_pages;
1996
1997 container = group->container;
1998 driver = container->iommu_driver;
1999 if (likely(driver && driver->ops->unpin_pages))
2000 ret = driver->ops->unpin_pages(container->iommu_data, user_pfn,
2001 npage);
2002 else
2003 ret = -ENOTTY;
2004
2005 vfio_group_try_dissolve_container(group);
2006
2007err_unpin_pages:
2008 vfio_group_put(group);
2009 return ret;
2010}
2011EXPORT_SYMBOL(vfio_unpin_pages);
2012
2013static int vfio_register_iommu_notifier(struct vfio_group *group,
2014 unsigned long *events,
2015 struct notifier_block *nb)
2016{
2017 struct vfio_container *container;
2018 struct vfio_iommu_driver *driver;
2019 int ret;
2020
2021 ret = vfio_group_add_container_user(group);
2022 if (ret)
2023 return -EINVAL;
2024
2025 container = group->container;
2026 driver = container->iommu_driver;
2027 if (likely(driver && driver->ops->register_notifier))
2028 ret = driver->ops->register_notifier(container->iommu_data,
2029 events, nb);
2030 else
2031 ret = -ENOTTY;
2032
2033 vfio_group_try_dissolve_container(group);
2034
2035 return ret;
2036}
2037
2038static int vfio_unregister_iommu_notifier(struct vfio_group *group,
2039 struct notifier_block *nb)
2040{
2041 struct vfio_container *container;
2042 struct vfio_iommu_driver *driver;
2043 int ret;
2044
2045 ret = vfio_group_add_container_user(group);
2046 if (ret)
2047 return -EINVAL;
2048
2049 container = group->container;
2050 driver = container->iommu_driver;
2051 if (likely(driver && driver->ops->unregister_notifier))
2052 ret = driver->ops->unregister_notifier(container->iommu_data,
2053 nb);
2054 else
2055 ret = -ENOTTY;
2056
2057 vfio_group_try_dissolve_container(group);
2058
2059 return ret;
2060}
2061
2062void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm)
2063{
2064 group->kvm = kvm;
2065 blocking_notifier_call_chain(&group->notifier,
2066 VFIO_GROUP_NOTIFY_SET_KVM, kvm);
2067}
2068EXPORT_SYMBOL_GPL(vfio_group_set_kvm);
2069
2070static int vfio_register_group_notifier(struct vfio_group *group,
2071 unsigned long *events,
2072 struct notifier_block *nb)
2073{
2074 int ret;
2075 bool set_kvm = false;
2076
2077 if (*events & VFIO_GROUP_NOTIFY_SET_KVM)
2078 set_kvm = true;
2079
2080 /* clear known events */
2081 *events &= ~VFIO_GROUP_NOTIFY_SET_KVM;
2082
2083 /* refuse to continue if still events remaining */
2084 if (*events)
2085 return -EINVAL;
2086
2087 ret = vfio_group_add_container_user(group);
2088 if (ret)
2089 return -EINVAL;
2090
2091 ret = blocking_notifier_chain_register(&group->notifier, nb);
2092
2093 /*
2094 * The attaching of kvm and vfio_group might already happen, so
2095 * here we replay once upon registration.
2096 */
2097 if (!ret && set_kvm && group->kvm)
2098 blocking_notifier_call_chain(&group->notifier,
2099 VFIO_GROUP_NOTIFY_SET_KVM, group->kvm);
2100
2101 vfio_group_try_dissolve_container(group);
2102
2103 return ret;
2104}
2105
2106static int vfio_unregister_group_notifier(struct vfio_group *group,
2107 struct notifier_block *nb)
2108{
2109 int ret;
2110
2111 ret = vfio_group_add_container_user(group);
2112 if (ret)
2113 return -EINVAL;
2114
2115 ret = blocking_notifier_chain_unregister(&group->notifier, nb);
2116
2117 vfio_group_try_dissolve_container(group);
2118
2119 return ret;
2120}
2121
2122int vfio_register_notifier(struct device *dev, enum vfio_notify_type type,
2123 unsigned long *events, struct notifier_block *nb)
2124{
2125 struct vfio_group *group;
2126 int ret;
2127
2128 if (!dev || !nb || !events || (*events == 0))
2129 return -EINVAL;
2130
2131 group = vfio_group_get_from_dev(dev);
2132 if (!group)
2133 return -ENODEV;
2134
2135 switch (type) {
2136 case VFIO_IOMMU_NOTIFY:
2137 ret = vfio_register_iommu_notifier(group, events, nb);
2138 break;
2139 case VFIO_GROUP_NOTIFY:
2140 ret = vfio_register_group_notifier(group, events, nb);
2141 break;
2142 default:
2143 ret = -EINVAL;
2144 }
2145
2146 vfio_group_put(group);
2147 return ret;
2148}
2149EXPORT_SYMBOL(vfio_register_notifier);
2150
2151int vfio_unregister_notifier(struct device *dev, enum vfio_notify_type type,
2152 struct notifier_block *nb)
2153{
2154 struct vfio_group *group;
2155 int ret;
2156
2157 if (!dev || !nb)
2158 return -EINVAL;
2159
2160 group = vfio_group_get_from_dev(dev);
2161 if (!group)
2162 return -ENODEV;
2163
2164 switch (type) {
2165 case VFIO_IOMMU_NOTIFY:
2166 ret = vfio_unregister_iommu_notifier(group, nb);
2167 break;
2168 case VFIO_GROUP_NOTIFY:
2169 ret = vfio_unregister_group_notifier(group, nb);
2170 break;
2171 default:
2172 ret = -EINVAL;
2173 }
2174
2175 vfio_group_put(group);
2176 return ret;
2177}
2178EXPORT_SYMBOL(vfio_unregister_notifier);
2179
2180/**
2181 * Module/class support
2182 */
2183static char *vfio_devnode(struct device *dev, umode_t *mode)
2184{
2185 return kasprintf(GFP_KERNEL, "vfio/%s", dev_name(dev));
2186}
2187
2188static struct miscdevice vfio_dev = {
2189 .minor = VFIO_MINOR,
2190 .name = "vfio",
2191 .fops = &vfio_fops,
2192 .nodename = "vfio/vfio",
2193 .mode = S_IRUGO | S_IWUGO,
2194};
2195
2196static int __init vfio_init(void)
2197{
2198 int ret;
2199
2200 idr_init(&vfio.group_idr);
2201 mutex_init(&vfio.group_lock);
2202 mutex_init(&vfio.iommu_drivers_lock);
2203 INIT_LIST_HEAD(&vfio.group_list);
2204 INIT_LIST_HEAD(&vfio.iommu_drivers_list);
2205 init_waitqueue_head(&vfio.release_q);
2206
2207 ret = misc_register(&vfio_dev);
2208 if (ret) {
2209 pr_err("vfio: misc device register failed\n");
2210 return ret;
2211 }
2212
2213 /* /dev/vfio/$GROUP */
2214 vfio.class = class_create(THIS_MODULE, "vfio");
2215 if (IS_ERR(vfio.class)) {
2216 ret = PTR_ERR(vfio.class);
2217 goto err_class;
2218 }
2219
2220 vfio.class->devnode = vfio_devnode;
2221
2222 ret = alloc_chrdev_region(&vfio.group_devt, 0, MINORMASK + 1, "vfio");
2223 if (ret)
2224 goto err_alloc_chrdev;
2225
2226 cdev_init(&vfio.group_cdev, &vfio_group_fops);
2227 ret = cdev_add(&vfio.group_cdev, vfio.group_devt, MINORMASK + 1);
2228 if (ret)
2229 goto err_cdev_add;
2230
2231 pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
2232
2233#ifdef CONFIG_VFIO_NOIOMMU
2234 vfio_register_iommu_driver(&vfio_noiommu_ops);
2235#endif
2236 return 0;
2237
2238err_cdev_add:
2239 unregister_chrdev_region(vfio.group_devt, MINORMASK + 1);
2240err_alloc_chrdev:
2241 class_destroy(vfio.class);
2242 vfio.class = NULL;
2243err_class:
2244 misc_deregister(&vfio_dev);
2245 return ret;
2246}
2247
2248static void __exit vfio_cleanup(void)
2249{
2250 WARN_ON(!list_empty(&vfio.group_list));
2251
2252#ifdef CONFIG_VFIO_NOIOMMU
2253 vfio_unregister_iommu_driver(&vfio_noiommu_ops);
2254#endif
2255 idr_destroy(&vfio.group_idr);
2256 cdev_del(&vfio.group_cdev);
2257 unregister_chrdev_region(vfio.group_devt, MINORMASK + 1);
2258 class_destroy(vfio.class);
2259 vfio.class = NULL;
2260 misc_deregister(&vfio_dev);
2261}
2262
2263module_init(vfio_init);
2264module_exit(vfio_cleanup);
2265
2266MODULE_VERSION(DRIVER_VERSION);
2267MODULE_LICENSE("GPL v2");
2268MODULE_AUTHOR(DRIVER_AUTHOR);
2269MODULE_DESCRIPTION(DRIVER_DESC);
2270MODULE_ALIAS_MISCDEV(VFIO_MINOR);
2271MODULE_ALIAS("devname:vfio/vfio");
2272MODULE_SOFTDEP("post: vfio_iommu_type1 vfio_iommu_spapr_tce");
2273