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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 int i;
634
635 if (dev_is_pci(dev)) {
636 struct pci_dev *pdev = to_pci_dev(dev);
637
638 if (pdev->hdr_type != PCI_HEADER_TYPE_NORMAL)
639 return true;
640 }
641
642 for (i = 0; i < ARRAY_SIZE(vfio_driver_whitelist); i++) {
643 if (!strcmp(drv->name, vfio_driver_whitelist[i]))
644 return true;
645 }
646
647 return false;
648}
649
650/*
651 * A vfio group is viable for use by userspace if all devices are in
652 * one of the following states:
653 * - driver-less
654 * - bound to a vfio driver
655 * - bound to a whitelisted driver
656 * - a PCI interconnect device
657 *
658 * We use two methods to determine whether a device is bound to a vfio
659 * driver. The first is to test whether the device exists in the vfio
660 * group. The second is to test if the device exists on the group
661 * unbound_list, indicating it's in the middle of transitioning from
662 * a vfio driver to driver-less.
663 */
664static int vfio_dev_viable(struct device *dev, void *data)
665{
666 struct vfio_group *group = data;
667 struct vfio_device *device;
668 struct device_driver *drv = READ_ONCE(dev->driver);
669 struct vfio_unbound_dev *unbound;
670 int ret = -EINVAL;
671
672 mutex_lock(&group->unbound_lock);
673 list_for_each_entry(unbound, &group->unbound_list, unbound_next) {
674 if (dev == unbound->dev) {
675 ret = 0;
676 break;
677 }
678 }
679 mutex_unlock(&group->unbound_lock);
680
681 if (!ret || !drv || vfio_dev_whitelisted(dev, drv))
682 return 0;
683
684 device = vfio_group_get_device(group, dev);
685 if (device) {
686 vfio_device_put(device);
687 return 0;
688 }
689
690 return ret;
691}
692
693/**
694 * Async device support
695 */
696static int vfio_group_nb_add_dev(struct vfio_group *group, struct device *dev)
697{
698 struct vfio_device *device;
699
700 /* Do we already know about it? We shouldn't */
701 device = vfio_group_get_device(group, dev);
702 if (WARN_ON_ONCE(device)) {
703 vfio_device_put(device);
704 return 0;
705 }
706
707 /* Nothing to do for idle groups */
708 if (!atomic_read(&group->container_users))
709 return 0;
710
711 /* TODO Prevent device auto probing */
712 WARN(1, "Device %s added to live group %d!\n", dev_name(dev),
713 iommu_group_id(group->iommu_group));
714
715 return 0;
716}
717
718static int vfio_group_nb_verify(struct vfio_group *group, struct device *dev)
719{
720 /* We don't care what happens when the group isn't in use */
721 if (!atomic_read(&group->container_users))
722 return 0;
723
724 return vfio_dev_viable(dev, group);
725}
726
727static int vfio_iommu_group_notifier(struct notifier_block *nb,
728 unsigned long action, void *data)
729{
730 struct vfio_group *group = container_of(nb, struct vfio_group, nb);
731 struct device *dev = data;
732 struct vfio_unbound_dev *unbound;
733
734 /*
735 * Need to go through a group_lock lookup to get a reference or we
736 * risk racing a group being removed. Ignore spurious notifies.
737 */
738 group = vfio_group_try_get(group);
739 if (!group)
740 return NOTIFY_OK;
741
742 switch (action) {
743 case IOMMU_GROUP_NOTIFY_ADD_DEVICE:
744 vfio_group_nb_add_dev(group, dev);
745 break;
746 case IOMMU_GROUP_NOTIFY_DEL_DEVICE:
747 /*
748 * Nothing to do here. If the device is in use, then the
749 * vfio sub-driver should block the remove callback until
750 * it is unused. If the device is unused or attached to a
751 * stub driver, then it should be released and we don't
752 * care that it will be going away.
753 */
754 break;
755 case IOMMU_GROUP_NOTIFY_BIND_DRIVER:
756 pr_debug("%s: Device %s, group %d binding to driver\n",
757 __func__, dev_name(dev),
758 iommu_group_id(group->iommu_group));
759 break;
760 case IOMMU_GROUP_NOTIFY_BOUND_DRIVER:
761 pr_debug("%s: Device %s, group %d bound to driver %s\n",
762 __func__, dev_name(dev),
763 iommu_group_id(group->iommu_group), dev->driver->name);
764 BUG_ON(vfio_group_nb_verify(group, dev));
765 break;
766 case IOMMU_GROUP_NOTIFY_UNBIND_DRIVER:
767 pr_debug("%s: Device %s, group %d unbinding from driver %s\n",
768 __func__, dev_name(dev),
769 iommu_group_id(group->iommu_group), dev->driver->name);
770 break;
771 case IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER:
772 pr_debug("%s: Device %s, group %d unbound from driver\n",
773 __func__, dev_name(dev),
774 iommu_group_id(group->iommu_group));
775 /*
776 * XXX An unbound device in a live group is ok, but we'd
777 * really like to avoid the above BUG_ON by preventing other
778 * drivers from binding to it. Once that occurs, we have to
779 * stop the system to maintain isolation. At a minimum, we'd
780 * want a toggle to disable driver auto probe for this device.
781 */
782
783 mutex_lock(&group->unbound_lock);
784 list_for_each_entry(unbound,
785 &group->unbound_list, unbound_next) {
786 if (dev == unbound->dev) {
787 list_del(&unbound->unbound_next);
788 kfree(unbound);
789 break;
790 }
791 }
792 mutex_unlock(&group->unbound_lock);
793 break;
794 }
795
796 /*
797 * If we're the last reference to the group, the group will be
798 * released, which includes unregistering the iommu group notifier.
799 * We hold a read-lock on that notifier list, unregistering needs
800 * a write-lock... deadlock. Release our reference asynchronously
801 * to avoid that situation.
802 */
803 vfio_group_schedule_put(group);
804 return NOTIFY_OK;
805}
806
807/**
808 * VFIO driver API
809 */
810int vfio_add_group_dev(struct device *dev,
811 const struct vfio_device_ops *ops, void *device_data)
812{
813 struct iommu_group *iommu_group;
814 struct vfio_group *group;
815 struct vfio_device *device;
816
817 iommu_group = iommu_group_get(dev);
818 if (!iommu_group)
819 return -EINVAL;
820
821 group = vfio_group_get_from_iommu(iommu_group);
822 if (!group) {
823 group = vfio_create_group(iommu_group);
824 if (IS_ERR(group)) {
825 iommu_group_put(iommu_group);
826 return PTR_ERR(group);
827 }
828 } else {
829 /*
830 * A found vfio_group already holds a reference to the
831 * iommu_group. A created vfio_group keeps the reference.
832 */
833 iommu_group_put(iommu_group);
834 }
835
836 device = vfio_group_get_device(group, dev);
837 if (device) {
838 WARN(1, "Device %s already exists on group %d\n",
839 dev_name(dev), iommu_group_id(iommu_group));
840 vfio_device_put(device);
841 vfio_group_put(group);
842 return -EBUSY;
843 }
844
845 device = vfio_group_create_device(group, dev, ops, device_data);
846 if (IS_ERR(device)) {
847 vfio_group_put(group);
848 return PTR_ERR(device);
849 }
850
851 /*
852 * Drop all but the vfio_device reference. The vfio_device holds
853 * a reference to the vfio_group, which holds a reference to the
854 * iommu_group.
855 */
856 vfio_group_put(group);
857
858 return 0;
859}
860EXPORT_SYMBOL_GPL(vfio_add_group_dev);
861
862/**
863 * Get a reference to the vfio_device for a device. Even if the
864 * caller thinks they own the device, they could be racing with a
865 * release call path, so we can't trust drvdata for the shortcut.
866 * Go the long way around, from the iommu_group to the vfio_group
867 * to the vfio_device.
868 */
869struct vfio_device *vfio_device_get_from_dev(struct device *dev)
870{
871 struct vfio_group *group;
872 struct vfio_device *device;
873
874 group = vfio_group_get_from_dev(dev);
875 if (!group)
876 return NULL;
877
878 device = vfio_group_get_device(group, dev);
879 vfio_group_put(group);
880
881 return device;
882}
883EXPORT_SYMBOL_GPL(vfio_device_get_from_dev);
884
885static struct vfio_device *vfio_device_get_from_name(struct vfio_group *group,
886 char *buf)
887{
888 struct vfio_device *it, *device = NULL;
889
890 mutex_lock(&group->device_lock);
891 list_for_each_entry(it, &group->device_list, group_next) {
892 if (!strcmp(dev_name(it->dev), buf)) {
893 device = it;
894 vfio_device_get(device);
895 break;
896 }
897 }
898 mutex_unlock(&group->device_lock);
899
900 return device;
901}
902
903/*
904 * Caller must hold a reference to the vfio_device
905 */
906void *vfio_device_data(struct vfio_device *device)
907{
908 return device->device_data;
909}
910EXPORT_SYMBOL_GPL(vfio_device_data);
911
912/* Given a referenced group, check if it contains the device */
913static bool vfio_dev_present(struct vfio_group *group, struct device *dev)
914{
915 struct vfio_device *device;
916
917 device = vfio_group_get_device(group, dev);
918 if (!device)
919 return false;
920
921 vfio_device_put(device);
922 return true;
923}
924
925/*
926 * Decrement the device reference count and wait for the device to be
927 * removed. Open file descriptors for the device... */
928void *vfio_del_group_dev(struct device *dev)
929{
930 struct vfio_device *device = dev_get_drvdata(dev);
931 struct vfio_group *group = device->group;
932 void *device_data = device->device_data;
933 struct vfio_unbound_dev *unbound;
934 unsigned int i = 0;
935 long ret;
936 bool interrupted = false;
937
938 /*
939 * The group exists so long as we have a device reference. Get
940 * a group reference and use it to scan for the device going away.
941 */
942 vfio_group_get(group);
943
944 /*
945 * When the device is removed from the group, the group suddenly
946 * becomes non-viable; the device has a driver (until the unbind
947 * completes), but it's not present in the group. This is bad news
948 * for any external users that need to re-acquire a group reference
949 * in order to match and release their existing reference. To
950 * solve this, we track such devices on the unbound_list to bridge
951 * the gap until they're fully unbound.
952 */
953 unbound = kzalloc(sizeof(*unbound), GFP_KERNEL);
954 if (unbound) {
955 unbound->dev = dev;
956 mutex_lock(&group->unbound_lock);
957 list_add(&unbound->unbound_next, &group->unbound_list);
958 mutex_unlock(&group->unbound_lock);
959 }
960 WARN_ON(!unbound);
961
962 vfio_device_put(device);
963
964 /*
965 * If the device is still present in the group after the above
966 * 'put', then it is in use and we need to request it from the
967 * bus driver. The driver may in turn need to request the
968 * device from the user. We send the request on an arbitrary
969 * interval with counter to allow the driver to take escalating
970 * measures to release the device if it has the ability to do so.
971 */
972 do {
973 device = vfio_group_get_device(group, dev);
974 if (!device)
975 break;
976
977 if (device->ops->request)
978 device->ops->request(device_data, i++);
979
980 vfio_device_put(device);
981
982 if (interrupted) {
983 ret = wait_event_timeout(vfio.release_q,
984 !vfio_dev_present(group, dev), HZ * 10);
985 } else {
986 ret = wait_event_interruptible_timeout(vfio.release_q,
987 !vfio_dev_present(group, dev), HZ * 10);
988 if (ret == -ERESTARTSYS) {
989 interrupted = true;
990 dev_warn(dev,
991 "Device is currently in use, task"
992 " \"%s\" (%d) "
993 "blocked until device is released",
994 current->comm, task_pid_nr(current));
995 }
996 }
997 } while (ret <= 0);
998
999 /*
1000 * In order to support multiple devices per group, devices can be
1001 * plucked from the group while other devices in the group are still
1002 * in use. The container persists with this group and those remaining
1003 * devices still attached. If the user creates an isolation violation
1004 * by binding this device to another driver while the group is still in
1005 * use, that's their fault. However, in the case of removing the last,
1006 * or potentially the only, device in the group there can be no other
1007 * in-use devices in the group. The user has done their due diligence
1008 * and we should lay no claims to those devices. In order to do that,
1009 * we need to make sure the group is detached from the container.
1010 * Without this stall, we're potentially racing with a user process
1011 * that may attempt to immediately bind this device to another driver.
1012 */
1013 if (list_empty(&group->device_list))
1014 wait_event(group->container_q, !group->container);
1015
1016 vfio_group_put(group);
1017
1018 return device_data;
1019}
1020EXPORT_SYMBOL_GPL(vfio_del_group_dev);
1021
1022/**
1023 * VFIO base fd, /dev/vfio/vfio
1024 */
1025static long vfio_ioctl_check_extension(struct vfio_container *container,
1026 unsigned long arg)
1027{
1028 struct vfio_iommu_driver *driver;
1029 long ret = 0;
1030
1031 down_read(&container->group_lock);
1032
1033 driver = container->iommu_driver;
1034
1035 switch (arg) {
1036 /* No base extensions yet */
1037 default:
1038 /*
1039 * If no driver is set, poll all registered drivers for
1040 * extensions and return the first positive result. If
1041 * a driver is already set, further queries will be passed
1042 * only to that driver.
1043 */
1044 if (!driver) {
1045 mutex_lock(&vfio.iommu_drivers_lock);
1046 list_for_each_entry(driver, &vfio.iommu_drivers_list,
1047 vfio_next) {
1048
1049#ifdef CONFIG_VFIO_NOIOMMU
1050 if (!list_empty(&container->group_list) &&
1051 (container->noiommu !=
1052 (driver->ops == &vfio_noiommu_ops)))
1053 continue;
1054#endif
1055
1056 if (!try_module_get(driver->ops->owner))
1057 continue;
1058
1059 ret = driver->ops->ioctl(NULL,
1060 VFIO_CHECK_EXTENSION,
1061 arg);
1062 module_put(driver->ops->owner);
1063 if (ret > 0)
1064 break;
1065 }
1066 mutex_unlock(&vfio.iommu_drivers_lock);
1067 } else
1068 ret = driver->ops->ioctl(container->iommu_data,
1069 VFIO_CHECK_EXTENSION, arg);
1070 }
1071
1072 up_read(&container->group_lock);
1073
1074 return ret;
1075}
1076
1077/* hold write lock on container->group_lock */
1078static int __vfio_container_attach_groups(struct vfio_container *container,
1079 struct vfio_iommu_driver *driver,
1080 void *data)
1081{
1082 struct vfio_group *group;
1083 int ret = -ENODEV;
1084
1085 list_for_each_entry(group, &container->group_list, container_next) {
1086 ret = driver->ops->attach_group(data, group->iommu_group);
1087 if (ret)
1088 goto unwind;
1089 }
1090
1091 return ret;
1092
1093unwind:
1094 list_for_each_entry_continue_reverse(group, &container->group_list,
1095 container_next) {
1096 driver->ops->detach_group(data, group->iommu_group);
1097 }
1098
1099 return ret;
1100}
1101
1102static long vfio_ioctl_set_iommu(struct vfio_container *container,
1103 unsigned long arg)
1104{
1105 struct vfio_iommu_driver *driver;
1106 long ret = -ENODEV;
1107
1108 down_write(&container->group_lock);
1109
1110 /*
1111 * The container is designed to be an unprivileged interface while
1112 * the group can be assigned to specific users. Therefore, only by
1113 * adding a group to a container does the user get the privilege of
1114 * enabling the iommu, which may allocate finite resources. There
1115 * is no unset_iommu, but by removing all the groups from a container,
1116 * the container is deprivileged and returns to an unset state.
1117 */
1118 if (list_empty(&container->group_list) || container->iommu_driver) {
1119 up_write(&container->group_lock);
1120 return -EINVAL;
1121 }
1122
1123 mutex_lock(&vfio.iommu_drivers_lock);
1124 list_for_each_entry(driver, &vfio.iommu_drivers_list, vfio_next) {
1125 void *data;
1126
1127#ifdef CONFIG_VFIO_NOIOMMU
1128 /*
1129 * Only noiommu containers can use vfio-noiommu and noiommu
1130 * containers can only use vfio-noiommu.
1131 */
1132 if (container->noiommu != (driver->ops == &vfio_noiommu_ops))
1133 continue;
1134#endif
1135
1136 if (!try_module_get(driver->ops->owner))
1137 continue;
1138
1139 /*
1140 * The arg magic for SET_IOMMU is the same as CHECK_EXTENSION,
1141 * so test which iommu driver reported support for this
1142 * extension and call open on them. We also pass them the
1143 * magic, allowing a single driver to support multiple
1144 * interfaces if they'd like.
1145 */
1146 if (driver->ops->ioctl(NULL, VFIO_CHECK_EXTENSION, arg) <= 0) {
1147 module_put(driver->ops->owner);
1148 continue;
1149 }
1150
1151 data = driver->ops->open(arg);
1152 if (IS_ERR(data)) {
1153 ret = PTR_ERR(data);
1154 module_put(driver->ops->owner);
1155 continue;
1156 }
1157
1158 ret = __vfio_container_attach_groups(container, driver, data);
1159 if (ret) {
1160 driver->ops->release(data);
1161 module_put(driver->ops->owner);
1162 continue;
1163 }
1164
1165 container->iommu_driver = driver;
1166 container->iommu_data = data;
1167 break;
1168 }
1169
1170 mutex_unlock(&vfio.iommu_drivers_lock);
1171 up_write(&container->group_lock);
1172
1173 return ret;
1174}
1175
1176static long vfio_fops_unl_ioctl(struct file *filep,
1177 unsigned int cmd, unsigned long arg)
1178{
1179 struct vfio_container *container = filep->private_data;
1180 struct vfio_iommu_driver *driver;
1181 void *data;
1182 long ret = -EINVAL;
1183
1184 if (!container)
1185 return ret;
1186
1187 switch (cmd) {
1188 case VFIO_GET_API_VERSION:
1189 ret = VFIO_API_VERSION;
1190 break;
1191 case VFIO_CHECK_EXTENSION:
1192 ret = vfio_ioctl_check_extension(container, arg);
1193 break;
1194 case VFIO_SET_IOMMU:
1195 ret = vfio_ioctl_set_iommu(container, arg);
1196 break;
1197 default:
1198 driver = container->iommu_driver;
1199 data = container->iommu_data;
1200
1201 if (driver) /* passthrough all unrecognized ioctls */
1202 ret = driver->ops->ioctl(data, cmd, arg);
1203 }
1204
1205 return ret;
1206}
1207
1208#ifdef CONFIG_COMPAT
1209static long vfio_fops_compat_ioctl(struct file *filep,
1210 unsigned int cmd, unsigned long arg)
1211{
1212 arg = (unsigned long)compat_ptr(arg);
1213 return vfio_fops_unl_ioctl(filep, cmd, arg);
1214}
1215#endif /* CONFIG_COMPAT */
1216
1217static int vfio_fops_open(struct inode *inode, struct file *filep)
1218{
1219 struct vfio_container *container;
1220
1221 container = kzalloc(sizeof(*container), GFP_KERNEL);
1222 if (!container)
1223 return -ENOMEM;
1224
1225 INIT_LIST_HEAD(&container->group_list);
1226 init_rwsem(&container->group_lock);
1227 kref_init(&container->kref);
1228
1229 filep->private_data = container;
1230
1231 return 0;
1232}
1233
1234static int vfio_fops_release(struct inode *inode, struct file *filep)
1235{
1236 struct vfio_container *container = filep->private_data;
1237
1238 filep->private_data = NULL;
1239
1240 vfio_container_put(container);
1241
1242 return 0;
1243}
1244
1245/*
1246 * Once an iommu driver is set, we optionally pass read/write/mmap
1247 * on to the driver, allowing management interfaces beyond ioctl.
1248 */
1249static ssize_t vfio_fops_read(struct file *filep, char __user *buf,
1250 size_t count, loff_t *ppos)
1251{
1252 struct vfio_container *container = filep->private_data;
1253 struct vfio_iommu_driver *driver;
1254 ssize_t ret = -EINVAL;
1255
1256 driver = container->iommu_driver;
1257 if (likely(driver && driver->ops->read))
1258 ret = driver->ops->read(container->iommu_data,
1259 buf, count, ppos);
1260
1261 return ret;
1262}
1263
1264static ssize_t vfio_fops_write(struct file *filep, const char __user *buf,
1265 size_t count, loff_t *ppos)
1266{
1267 struct vfio_container *container = filep->private_data;
1268 struct vfio_iommu_driver *driver;
1269 ssize_t ret = -EINVAL;
1270
1271 driver = container->iommu_driver;
1272 if (likely(driver && driver->ops->write))
1273 ret = driver->ops->write(container->iommu_data,
1274 buf, count, ppos);
1275
1276 return ret;
1277}
1278
1279static int vfio_fops_mmap(struct file *filep, struct vm_area_struct *vma)
1280{
1281 struct vfio_container *container = filep->private_data;
1282 struct vfio_iommu_driver *driver;
1283 int ret = -EINVAL;
1284
1285 driver = container->iommu_driver;
1286 if (likely(driver && driver->ops->mmap))
1287 ret = driver->ops->mmap(container->iommu_data, vma);
1288
1289 return ret;
1290}
1291
1292static const struct file_operations vfio_fops = {
1293 .owner = THIS_MODULE,
1294 .open = vfio_fops_open,
1295 .release = vfio_fops_release,
1296 .read = vfio_fops_read,
1297 .write = vfio_fops_write,
1298 .unlocked_ioctl = vfio_fops_unl_ioctl,
1299#ifdef CONFIG_COMPAT
1300 .compat_ioctl = vfio_fops_compat_ioctl,
1301#endif
1302 .mmap = vfio_fops_mmap,
1303};
1304
1305/**
1306 * VFIO Group fd, /dev/vfio/$GROUP
1307 */
1308static void __vfio_group_unset_container(struct vfio_group *group)
1309{
1310 struct vfio_container *container = group->container;
1311 struct vfio_iommu_driver *driver;
1312
1313 down_write(&container->group_lock);
1314
1315 driver = container->iommu_driver;
1316 if (driver)
1317 driver->ops->detach_group(container->iommu_data,
1318 group->iommu_group);
1319
1320 group->container = NULL;
1321 wake_up(&group->container_q);
1322 list_del(&group->container_next);
1323
1324 /* Detaching the last group deprivileges a container, remove iommu */
1325 if (driver && list_empty(&container->group_list)) {
1326 driver->ops->release(container->iommu_data);
1327 module_put(driver->ops->owner);
1328 container->iommu_driver = NULL;
1329 container->iommu_data = NULL;
1330 }
1331
1332 up_write(&container->group_lock);
1333
1334 vfio_container_put(container);
1335}
1336
1337/*
1338 * VFIO_GROUP_UNSET_CONTAINER should fail if there are other users or
1339 * if there was no container to unset. Since the ioctl is called on
1340 * the group, we know that still exists, therefore the only valid
1341 * transition here is 1->0.
1342 */
1343static int vfio_group_unset_container(struct vfio_group *group)
1344{
1345 int users = atomic_cmpxchg(&group->container_users, 1, 0);
1346
1347 if (!users)
1348 return -EINVAL;
1349 if (users != 1)
1350 return -EBUSY;
1351
1352 __vfio_group_unset_container(group);
1353
1354 return 0;
1355}
1356
1357/*
1358 * When removing container users, anything that removes the last user
1359 * implicitly removes the group from the container. That is, if the
1360 * group file descriptor is closed, as well as any device file descriptors,
1361 * the group is free.
1362 */
1363static void vfio_group_try_dissolve_container(struct vfio_group *group)
1364{
1365 if (0 == atomic_dec_if_positive(&group->container_users))
1366 __vfio_group_unset_container(group);
1367}
1368
1369static int vfio_group_set_container(struct vfio_group *group, int container_fd)
1370{
1371 struct fd f;
1372 struct vfio_container *container;
1373 struct vfio_iommu_driver *driver;
1374 int ret = 0;
1375
1376 if (atomic_read(&group->container_users))
1377 return -EINVAL;
1378
1379 if (group->noiommu && !capable(CAP_SYS_RAWIO))
1380 return -EPERM;
1381
1382 f = fdget(container_fd);
1383 if (!f.file)
1384 return -EBADF;
1385
1386 /* Sanity check, is this really our fd? */
1387 if (f.file->f_op != &vfio_fops) {
1388 fdput(f);
1389 return -EINVAL;
1390 }
1391
1392 container = f.file->private_data;
1393 WARN_ON(!container); /* fget ensures we don't race vfio_release */
1394
1395 down_write(&container->group_lock);
1396
1397 /* Real groups and fake groups cannot mix */
1398 if (!list_empty(&container->group_list) &&
1399 container->noiommu != group->noiommu) {
1400 ret = -EPERM;
1401 goto unlock_out;
1402 }
1403
1404 driver = container->iommu_driver;
1405 if (driver) {
1406 ret = driver->ops->attach_group(container->iommu_data,
1407 group->iommu_group);
1408 if (ret)
1409 goto unlock_out;
1410 }
1411
1412 group->container = container;
1413 container->noiommu = group->noiommu;
1414 list_add(&group->container_next, &container->group_list);
1415
1416 /* Get a reference on the container and mark a user within the group */
1417 vfio_container_get(container);
1418 atomic_inc(&group->container_users);
1419
1420unlock_out:
1421 up_write(&container->group_lock);
1422 fdput(f);
1423 return ret;
1424}
1425
1426static bool vfio_group_viable(struct vfio_group *group)
1427{
1428 return (iommu_group_for_each_dev(group->iommu_group,
1429 group, vfio_dev_viable) == 0);
1430}
1431
1432static int vfio_group_add_container_user(struct vfio_group *group)
1433{
1434 if (!atomic_inc_not_zero(&group->container_users))
1435 return -EINVAL;
1436
1437 if (group->noiommu) {
1438 atomic_dec(&group->container_users);
1439 return -EPERM;
1440 }
1441 if (!group->container->iommu_driver || !vfio_group_viable(group)) {
1442 atomic_dec(&group->container_users);
1443 return -EINVAL;
1444 }
1445
1446 return 0;
1447}
1448
1449static const struct file_operations vfio_device_fops;
1450
1451static int vfio_group_get_device_fd(struct vfio_group *group, char *buf)
1452{
1453 struct vfio_device *device;
1454 struct file *filep;
1455 int ret;
1456
1457 if (0 == atomic_read(&group->container_users) ||
1458 !group->container->iommu_driver || !vfio_group_viable(group))
1459 return -EINVAL;
1460
1461 if (group->noiommu && !capable(CAP_SYS_RAWIO))
1462 return -EPERM;
1463
1464 device = vfio_device_get_from_name(group, buf);
1465 if (!device)
1466 return -ENODEV;
1467
1468 ret = device->ops->open(device->device_data);
1469 if (ret) {
1470 vfio_device_put(device);
1471 return ret;
1472 }
1473
1474 /*
1475 * We can't use anon_inode_getfd() because we need to modify
1476 * the f_mode flags directly to allow more than just ioctls
1477 */
1478 ret = get_unused_fd_flags(O_CLOEXEC);
1479 if (ret < 0) {
1480 device->ops->release(device->device_data);
1481 vfio_device_put(device);
1482 return ret;
1483 }
1484
1485 filep = anon_inode_getfile("[vfio-device]", &vfio_device_fops,
1486 device, O_RDWR);
1487 if (IS_ERR(filep)) {
1488 put_unused_fd(ret);
1489 ret = PTR_ERR(filep);
1490 device->ops->release(device->device_data);
1491 vfio_device_put(device);
1492 return ret;
1493 }
1494
1495 /*
1496 * TODO: add an anon_inode interface to do this.
1497 * Appears to be missing by lack of need rather than
1498 * explicitly prevented. Now there's need.
1499 */
1500 filep->f_mode |= (FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE);
1501
1502 atomic_inc(&group->container_users);
1503
1504 fd_install(ret, filep);
1505
1506 if (group->noiommu)
1507 dev_warn(device->dev, "vfio-noiommu device opened by user "
1508 "(%s:%d)\n", current->comm, task_pid_nr(current));
1509
1510 return ret;
1511}
1512
1513static long vfio_group_fops_unl_ioctl(struct file *filep,
1514 unsigned int cmd, unsigned long arg)
1515{
1516 struct vfio_group *group = filep->private_data;
1517 long ret = -ENOTTY;
1518
1519 switch (cmd) {
1520 case VFIO_GROUP_GET_STATUS:
1521 {
1522 struct vfio_group_status status;
1523 unsigned long minsz;
1524
1525 minsz = offsetofend(struct vfio_group_status, flags);
1526
1527 if (copy_from_user(&status, (void __user *)arg, minsz))
1528 return -EFAULT;
1529
1530 if (status.argsz < minsz)
1531 return -EINVAL;
1532
1533 status.flags = 0;
1534
1535 if (vfio_group_viable(group))
1536 status.flags |= VFIO_GROUP_FLAGS_VIABLE;
1537
1538 if (group->container)
1539 status.flags |= VFIO_GROUP_FLAGS_CONTAINER_SET;
1540
1541 if (copy_to_user((void __user *)arg, &status, minsz))
1542 return -EFAULT;
1543
1544 ret = 0;
1545 break;
1546 }
1547 case VFIO_GROUP_SET_CONTAINER:
1548 {
1549 int fd;
1550
1551 if (get_user(fd, (int __user *)arg))
1552 return -EFAULT;
1553
1554 if (fd < 0)
1555 return -EINVAL;
1556
1557 ret = vfio_group_set_container(group, fd);
1558 break;
1559 }
1560 case VFIO_GROUP_UNSET_CONTAINER:
1561 ret = vfio_group_unset_container(group);
1562 break;
1563 case VFIO_GROUP_GET_DEVICE_FD:
1564 {
1565 char *buf;
1566
1567 buf = strndup_user((const char __user *)arg, PAGE_SIZE);
1568 if (IS_ERR(buf))
1569 return PTR_ERR(buf);
1570
1571 ret = vfio_group_get_device_fd(group, buf);
1572 kfree(buf);
1573 break;
1574 }
1575 }
1576
1577 return ret;
1578}
1579
1580#ifdef CONFIG_COMPAT
1581static long vfio_group_fops_compat_ioctl(struct file *filep,
1582 unsigned int cmd, unsigned long arg)
1583{
1584 arg = (unsigned long)compat_ptr(arg);
1585 return vfio_group_fops_unl_ioctl(filep, cmd, arg);
1586}
1587#endif /* CONFIG_COMPAT */
1588
1589static int vfio_group_fops_open(struct inode *inode, struct file *filep)
1590{
1591 struct vfio_group *group;
1592 int opened;
1593
1594 group = vfio_group_get_from_minor(iminor(inode));
1595 if (!group)
1596 return -ENODEV;
1597
1598 if (group->noiommu && !capable(CAP_SYS_RAWIO)) {
1599 vfio_group_put(group);
1600 return -EPERM;
1601 }
1602
1603 /* Do we need multiple instances of the group open? Seems not. */
1604 opened = atomic_cmpxchg(&group->opened, 0, 1);
1605 if (opened) {
1606 vfio_group_put(group);
1607 return -EBUSY;
1608 }
1609
1610 /* Is something still in use from a previous open? */
1611 if (group->container) {
1612 atomic_dec(&group->opened);
1613 vfio_group_put(group);
1614 return -EBUSY;
1615 }
1616
1617 /* Warn if previous user didn't cleanup and re-init to drop them */
1618 if (WARN_ON(group->notifier.head))
1619 BLOCKING_INIT_NOTIFIER_HEAD(&group->notifier);
1620
1621 filep->private_data = group;
1622
1623 return 0;
1624}
1625
1626static int vfio_group_fops_release(struct inode *inode, struct file *filep)
1627{
1628 struct vfio_group *group = filep->private_data;
1629
1630 filep->private_data = NULL;
1631
1632 vfio_group_try_dissolve_container(group);
1633
1634 atomic_dec(&group->opened);
1635
1636 vfio_group_put(group);
1637
1638 return 0;
1639}
1640
1641static const struct file_operations vfio_group_fops = {
1642 .owner = THIS_MODULE,
1643 .unlocked_ioctl = vfio_group_fops_unl_ioctl,
1644#ifdef CONFIG_COMPAT
1645 .compat_ioctl = vfio_group_fops_compat_ioctl,
1646#endif
1647 .open = vfio_group_fops_open,
1648 .release = vfio_group_fops_release,
1649};
1650
1651/**
1652 * VFIO Device fd
1653 */
1654static int vfio_device_fops_release(struct inode *inode, struct file *filep)
1655{
1656 struct vfio_device *device = filep->private_data;
1657
1658 device->ops->release(device->device_data);
1659
1660 vfio_group_try_dissolve_container(device->group);
1661
1662 vfio_device_put(device);
1663
1664 return 0;
1665}
1666
1667static long vfio_device_fops_unl_ioctl(struct file *filep,
1668 unsigned int cmd, unsigned long arg)
1669{
1670 struct vfio_device *device = filep->private_data;
1671
1672 if (unlikely(!device->ops->ioctl))
1673 return -EINVAL;
1674
1675 return device->ops->ioctl(device->device_data, cmd, arg);
1676}
1677
1678static ssize_t vfio_device_fops_read(struct file *filep, char __user *buf,
1679 size_t count, loff_t *ppos)
1680{
1681 struct vfio_device *device = filep->private_data;
1682
1683 if (unlikely(!device->ops->read))
1684 return -EINVAL;
1685
1686 return device->ops->read(device->device_data, buf, count, ppos);
1687}
1688
1689static ssize_t vfio_device_fops_write(struct file *filep,
1690 const char __user *buf,
1691 size_t count, loff_t *ppos)
1692{
1693 struct vfio_device *device = filep->private_data;
1694
1695 if (unlikely(!device->ops->write))
1696 return -EINVAL;
1697
1698 return device->ops->write(device->device_data, buf, count, ppos);
1699}
1700
1701static int vfio_device_fops_mmap(struct file *filep, struct vm_area_struct *vma)
1702{
1703 struct vfio_device *device = filep->private_data;
1704
1705 if (unlikely(!device->ops->mmap))
1706 return -EINVAL;
1707
1708 return device->ops->mmap(device->device_data, vma);
1709}
1710
1711#ifdef CONFIG_COMPAT
1712static long vfio_device_fops_compat_ioctl(struct file *filep,
1713 unsigned int cmd, unsigned long arg)
1714{
1715 arg = (unsigned long)compat_ptr(arg);
1716 return vfio_device_fops_unl_ioctl(filep, cmd, arg);
1717}
1718#endif /* CONFIG_COMPAT */
1719
1720static const struct file_operations vfio_device_fops = {
1721 .owner = THIS_MODULE,
1722 .release = vfio_device_fops_release,
1723 .read = vfio_device_fops_read,
1724 .write = vfio_device_fops_write,
1725 .unlocked_ioctl = vfio_device_fops_unl_ioctl,
1726#ifdef CONFIG_COMPAT
1727 .compat_ioctl = vfio_device_fops_compat_ioctl,
1728#endif
1729 .mmap = vfio_device_fops_mmap,
1730};
1731
1732/**
1733 * External user API, exported by symbols to be linked dynamically.
1734 *
1735 * The protocol includes:
1736 * 1. do normal VFIO init operation:
1737 * - opening a new container;
1738 * - attaching group(s) to it;
1739 * - setting an IOMMU driver for a container.
1740 * When IOMMU is set for a container, all groups in it are
1741 * considered ready to use by an external user.
1742 *
1743 * 2. User space passes a group fd to an external user.
1744 * The external user calls vfio_group_get_external_user()
1745 * to verify that:
1746 * - the group is initialized;
1747 * - IOMMU is set for it.
1748 * If both checks passed, vfio_group_get_external_user()
1749 * increments the container user counter to prevent
1750 * the VFIO group from disposal before KVM exits.
1751 *
1752 * 3. The external user calls vfio_external_user_iommu_id()
1753 * to know an IOMMU ID.
1754 *
1755 * 4. When the external KVM finishes, it calls
1756 * vfio_group_put_external_user() to release the VFIO group.
1757 * This call decrements the container user counter.
1758 */
1759struct vfio_group *vfio_group_get_external_user(struct file *filep)
1760{
1761 struct vfio_group *group = filep->private_data;
1762 int ret;
1763
1764 if (filep->f_op != &vfio_group_fops)
1765 return ERR_PTR(-EINVAL);
1766
1767 ret = vfio_group_add_container_user(group);
1768 if (ret)
1769 return ERR_PTR(ret);
1770
1771 vfio_group_get(group);
1772
1773 return group;
1774}
1775EXPORT_SYMBOL_GPL(vfio_group_get_external_user);
1776
1777void vfio_group_put_external_user(struct vfio_group *group)
1778{
1779 vfio_group_try_dissolve_container(group);
1780 vfio_group_put(group);
1781}
1782EXPORT_SYMBOL_GPL(vfio_group_put_external_user);
1783
1784bool vfio_external_group_match_file(struct vfio_group *test_group,
1785 struct file *filep)
1786{
1787 struct vfio_group *group = filep->private_data;
1788
1789 return (filep->f_op == &vfio_group_fops) && (group == test_group);
1790}
1791EXPORT_SYMBOL_GPL(vfio_external_group_match_file);
1792
1793int vfio_external_user_iommu_id(struct vfio_group *group)
1794{
1795 return iommu_group_id(group->iommu_group);
1796}
1797EXPORT_SYMBOL_GPL(vfio_external_user_iommu_id);
1798
1799long vfio_external_check_extension(struct vfio_group *group, unsigned long arg)
1800{
1801 return vfio_ioctl_check_extension(group->container, arg);
1802}
1803EXPORT_SYMBOL_GPL(vfio_external_check_extension);
1804
1805/**
1806 * Sub-module support
1807 */
1808/*
1809 * Helper for managing a buffer of info chain capabilities, allocate or
1810 * reallocate a buffer with additional @size, filling in @id and @version
1811 * of the capability. A pointer to the new capability is returned.
1812 *
1813 * NB. The chain is based at the head of the buffer, so new entries are
1814 * added to the tail, vfio_info_cap_shift() should be called to fixup the
1815 * next offsets prior to copying to the user buffer.
1816 */
1817struct vfio_info_cap_header *vfio_info_cap_add(struct vfio_info_cap *caps,
1818 size_t size, u16 id, u16 version)
1819{
1820 void *buf;
1821 struct vfio_info_cap_header *header, *tmp;
1822
1823 buf = krealloc(caps->buf, caps->size + size, GFP_KERNEL);
1824 if (!buf) {
1825 kfree(caps->buf);
1826 caps->size = 0;
1827 return ERR_PTR(-ENOMEM);
1828 }
1829
1830 caps->buf = buf;
1831 header = buf + caps->size;
1832
1833 /* Eventually copied to user buffer, zero */
1834 memset(header, 0, size);
1835
1836 header->id = id;
1837 header->version = version;
1838
1839 /* Add to the end of the capability chain */
1840 for (tmp = buf; tmp->next; tmp = buf + tmp->next)
1841 ; /* nothing */
1842
1843 tmp->next = caps->size;
1844 caps->size += size;
1845
1846 return header;
1847}
1848EXPORT_SYMBOL_GPL(vfio_info_cap_add);
1849
1850void vfio_info_cap_shift(struct vfio_info_cap *caps, size_t offset)
1851{
1852 struct vfio_info_cap_header *tmp;
1853 void *buf = (void *)caps->buf;
1854
1855 for (tmp = buf; tmp->next; tmp = buf + tmp->next - offset)
1856 tmp->next += offset;
1857}
1858EXPORT_SYMBOL(vfio_info_cap_shift);
1859
1860int vfio_info_add_capability(struct vfio_info_cap *caps,
1861 struct vfio_info_cap_header *cap, size_t size)
1862{
1863 struct vfio_info_cap_header *header;
1864
1865 header = vfio_info_cap_add(caps, size, cap->id, cap->version);
1866 if (IS_ERR(header))
1867 return PTR_ERR(header);
1868
1869 memcpy(header + 1, cap + 1, size - sizeof(*header));
1870
1871 return 0;
1872}
1873EXPORT_SYMBOL(vfio_info_add_capability);
1874
1875int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr, int num_irqs,
1876 int max_irq_type, size_t *data_size)
1877{
1878 unsigned long minsz;
1879 size_t size;
1880
1881 minsz = offsetofend(struct vfio_irq_set, count);
1882
1883 if ((hdr->argsz < minsz) || (hdr->index >= max_irq_type) ||
1884 (hdr->count >= (U32_MAX - hdr->start)) ||
1885 (hdr->flags & ~(VFIO_IRQ_SET_DATA_TYPE_MASK |
1886 VFIO_IRQ_SET_ACTION_TYPE_MASK)))
1887 return -EINVAL;
1888
1889 if (data_size)
1890 *data_size = 0;
1891
1892 if (hdr->start >= num_irqs || hdr->start + hdr->count > num_irqs)
1893 return -EINVAL;
1894
1895 switch (hdr->flags & VFIO_IRQ_SET_DATA_TYPE_MASK) {
1896 case VFIO_IRQ_SET_DATA_NONE:
1897 size = 0;
1898 break;
1899 case VFIO_IRQ_SET_DATA_BOOL:
1900 size = sizeof(uint8_t);
1901 break;
1902 case VFIO_IRQ_SET_DATA_EVENTFD:
1903 size = sizeof(int32_t);
1904 break;
1905 default:
1906 return -EINVAL;
1907 }
1908
1909 if (size) {
1910 if (hdr->argsz - minsz < hdr->count * size)
1911 return -EINVAL;
1912
1913 if (!data_size)
1914 return -EINVAL;
1915
1916 *data_size = hdr->count * size;
1917 }
1918
1919 return 0;
1920}
1921EXPORT_SYMBOL(vfio_set_irqs_validate_and_prepare);
1922
1923/*
1924 * Pin a set of guest PFNs and return their associated host PFNs for local
1925 * domain only.
1926 * @dev [in] : device
1927 * @user_pfn [in]: array of user/guest PFNs to be pinned.
1928 * @npage [in] : count of elements in user_pfn array. This count should not
1929 * be greater VFIO_PIN_PAGES_MAX_ENTRIES.
1930 * @prot [in] : protection flags
1931 * @phys_pfn[out]: array of host PFNs
1932 * Return error or number of pages pinned.
1933 */
1934int vfio_pin_pages(struct device *dev, unsigned long *user_pfn, int npage,
1935 int prot, unsigned long *phys_pfn)
1936{
1937 struct vfio_container *container;
1938 struct vfio_group *group;
1939 struct vfio_iommu_driver *driver;
1940 int ret;
1941
1942 if (!dev || !user_pfn || !phys_pfn || !npage)
1943 return -EINVAL;
1944
1945 if (npage > VFIO_PIN_PAGES_MAX_ENTRIES)
1946 return -E2BIG;
1947
1948 group = vfio_group_get_from_dev(dev);
1949 if (!group)
1950 return -ENODEV;
1951
1952 ret = vfio_group_add_container_user(group);
1953 if (ret)
1954 goto err_pin_pages;
1955
1956 container = group->container;
1957 driver = container->iommu_driver;
1958 if (likely(driver && driver->ops->pin_pages))
1959 ret = driver->ops->pin_pages(container->iommu_data, user_pfn,
1960 npage, prot, phys_pfn);
1961 else
1962 ret = -ENOTTY;
1963
1964 vfio_group_try_dissolve_container(group);
1965
1966err_pin_pages:
1967 vfio_group_put(group);
1968 return ret;
1969}
1970EXPORT_SYMBOL(vfio_pin_pages);
1971
1972/*
1973 * Unpin set of host PFNs for local domain only.
1974 * @dev [in] : device
1975 * @user_pfn [in]: array of user/guest PFNs to be unpinned. Number of user/guest
1976 * PFNs should not be greater than VFIO_PIN_PAGES_MAX_ENTRIES.
1977 * @npage [in] : count of elements in user_pfn array. This count should not
1978 * be greater than VFIO_PIN_PAGES_MAX_ENTRIES.
1979 * Return error or number of pages unpinned.
1980 */
1981int vfio_unpin_pages(struct device *dev, unsigned long *user_pfn, int npage)
1982{
1983 struct vfio_container *container;
1984 struct vfio_group *group;
1985 struct vfio_iommu_driver *driver;
1986 int ret;
1987
1988 if (!dev || !user_pfn || !npage)
1989 return -EINVAL;
1990
1991 if (npage > VFIO_PIN_PAGES_MAX_ENTRIES)
1992 return -E2BIG;
1993
1994 group = vfio_group_get_from_dev(dev);
1995 if (!group)
1996 return -ENODEV;
1997
1998 ret = vfio_group_add_container_user(group);
1999 if (ret)
2000 goto err_unpin_pages;
2001
2002 container = group->container;
2003 driver = container->iommu_driver;
2004 if (likely(driver && driver->ops->unpin_pages))
2005 ret = driver->ops->unpin_pages(container->iommu_data, user_pfn,
2006 npage);
2007 else
2008 ret = -ENOTTY;
2009
2010 vfio_group_try_dissolve_container(group);
2011
2012err_unpin_pages:
2013 vfio_group_put(group);
2014 return ret;
2015}
2016EXPORT_SYMBOL(vfio_unpin_pages);
2017
2018static int vfio_register_iommu_notifier(struct vfio_group *group,
2019 unsigned long *events,
2020 struct notifier_block *nb)
2021{
2022 struct vfio_container *container;
2023 struct vfio_iommu_driver *driver;
2024 int ret;
2025
2026 ret = vfio_group_add_container_user(group);
2027 if (ret)
2028 return -EINVAL;
2029
2030 container = group->container;
2031 driver = container->iommu_driver;
2032 if (likely(driver && driver->ops->register_notifier))
2033 ret = driver->ops->register_notifier(container->iommu_data,
2034 events, nb);
2035 else
2036 ret = -ENOTTY;
2037
2038 vfio_group_try_dissolve_container(group);
2039
2040 return ret;
2041}
2042
2043static int vfio_unregister_iommu_notifier(struct vfio_group *group,
2044 struct notifier_block *nb)
2045{
2046 struct vfio_container *container;
2047 struct vfio_iommu_driver *driver;
2048 int ret;
2049
2050 ret = vfio_group_add_container_user(group);
2051 if (ret)
2052 return -EINVAL;
2053
2054 container = group->container;
2055 driver = container->iommu_driver;
2056 if (likely(driver && driver->ops->unregister_notifier))
2057 ret = driver->ops->unregister_notifier(container->iommu_data,
2058 nb);
2059 else
2060 ret = -ENOTTY;
2061
2062 vfio_group_try_dissolve_container(group);
2063
2064 return ret;
2065}
2066
2067void vfio_group_set_kvm(struct vfio_group *group, struct kvm *kvm)
2068{
2069 group->kvm = kvm;
2070 blocking_notifier_call_chain(&group->notifier,
2071 VFIO_GROUP_NOTIFY_SET_KVM, kvm);
2072}
2073EXPORT_SYMBOL_GPL(vfio_group_set_kvm);
2074
2075static int vfio_register_group_notifier(struct vfio_group *group,
2076 unsigned long *events,
2077 struct notifier_block *nb)
2078{
2079 int ret;
2080 bool set_kvm = false;
2081
2082 if (*events & VFIO_GROUP_NOTIFY_SET_KVM)
2083 set_kvm = true;
2084
2085 /* clear known events */
2086 *events &= ~VFIO_GROUP_NOTIFY_SET_KVM;
2087
2088 /* refuse to continue if still events remaining */
2089 if (*events)
2090 return -EINVAL;
2091
2092 ret = vfio_group_add_container_user(group);
2093 if (ret)
2094 return -EINVAL;
2095
2096 ret = blocking_notifier_chain_register(&group->notifier, nb);
2097
2098 /*
2099 * The attaching of kvm and vfio_group might already happen, so
2100 * here we replay once upon registration.
2101 */
2102 if (!ret && set_kvm && group->kvm)
2103 blocking_notifier_call_chain(&group->notifier,
2104 VFIO_GROUP_NOTIFY_SET_KVM, group->kvm);
2105
2106 vfio_group_try_dissolve_container(group);
2107
2108 return ret;
2109}
2110
2111static int vfio_unregister_group_notifier(struct vfio_group *group,
2112 struct notifier_block *nb)
2113{
2114 int ret;
2115
2116 ret = vfio_group_add_container_user(group);
2117 if (ret)
2118 return -EINVAL;
2119
2120 ret = blocking_notifier_chain_unregister(&group->notifier, nb);
2121
2122 vfio_group_try_dissolve_container(group);
2123
2124 return ret;
2125}
2126
2127int vfio_register_notifier(struct device *dev, enum vfio_notify_type type,
2128 unsigned long *events, struct notifier_block *nb)
2129{
2130 struct vfio_group *group;
2131 int ret;
2132
2133 if (!dev || !nb || !events || (*events == 0))
2134 return -EINVAL;
2135
2136 group = vfio_group_get_from_dev(dev);
2137 if (!group)
2138 return -ENODEV;
2139
2140 switch (type) {
2141 case VFIO_IOMMU_NOTIFY:
2142 ret = vfio_register_iommu_notifier(group, events, nb);
2143 break;
2144 case VFIO_GROUP_NOTIFY:
2145 ret = vfio_register_group_notifier(group, events, nb);
2146 break;
2147 default:
2148 ret = -EINVAL;
2149 }
2150
2151 vfio_group_put(group);
2152 return ret;
2153}
2154EXPORT_SYMBOL(vfio_register_notifier);
2155
2156int vfio_unregister_notifier(struct device *dev, enum vfio_notify_type type,
2157 struct notifier_block *nb)
2158{
2159 struct vfio_group *group;
2160 int ret;
2161
2162 if (!dev || !nb)
2163 return -EINVAL;
2164
2165 group = vfio_group_get_from_dev(dev);
2166 if (!group)
2167 return -ENODEV;
2168
2169 switch (type) {
2170 case VFIO_IOMMU_NOTIFY:
2171 ret = vfio_unregister_iommu_notifier(group, nb);
2172 break;
2173 case VFIO_GROUP_NOTIFY:
2174 ret = vfio_unregister_group_notifier(group, nb);
2175 break;
2176 default:
2177 ret = -EINVAL;
2178 }
2179
2180 vfio_group_put(group);
2181 return ret;
2182}
2183EXPORT_SYMBOL(vfio_unregister_notifier);
2184
2185/**
2186 * Module/class support
2187 */
2188static char *vfio_devnode(struct device *dev, umode_t *mode)
2189{
2190 return kasprintf(GFP_KERNEL, "vfio/%s", dev_name(dev));
2191}
2192
2193static struct miscdevice vfio_dev = {
2194 .minor = VFIO_MINOR,
2195 .name = "vfio",
2196 .fops = &vfio_fops,
2197 .nodename = "vfio/vfio",
2198 .mode = S_IRUGO | S_IWUGO,
2199};
2200
2201static int __init vfio_init(void)
2202{
2203 int ret;
2204
2205 idr_init(&vfio.group_idr);
2206 mutex_init(&vfio.group_lock);
2207 mutex_init(&vfio.iommu_drivers_lock);
2208 INIT_LIST_HEAD(&vfio.group_list);
2209 INIT_LIST_HEAD(&vfio.iommu_drivers_list);
2210 init_waitqueue_head(&vfio.release_q);
2211
2212 ret = misc_register(&vfio_dev);
2213 if (ret) {
2214 pr_err("vfio: misc device register failed\n");
2215 return ret;
2216 }
2217
2218 /* /dev/vfio/$GROUP */
2219 vfio.class = class_create(THIS_MODULE, "vfio");
2220 if (IS_ERR(vfio.class)) {
2221 ret = PTR_ERR(vfio.class);
2222 goto err_class;
2223 }
2224
2225 vfio.class->devnode = vfio_devnode;
2226
2227 ret = alloc_chrdev_region(&vfio.group_devt, 0, MINORMASK, "vfio");
2228 if (ret)
2229 goto err_alloc_chrdev;
2230
2231 cdev_init(&vfio.group_cdev, &vfio_group_fops);
2232 ret = cdev_add(&vfio.group_cdev, vfio.group_devt, MINORMASK);
2233 if (ret)
2234 goto err_cdev_add;
2235
2236 pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
2237
2238#ifdef CONFIG_VFIO_NOIOMMU
2239 vfio_register_iommu_driver(&vfio_noiommu_ops);
2240#endif
2241 return 0;
2242
2243err_cdev_add:
2244 unregister_chrdev_region(vfio.group_devt, MINORMASK);
2245err_alloc_chrdev:
2246 class_destroy(vfio.class);
2247 vfio.class = NULL;
2248err_class:
2249 misc_deregister(&vfio_dev);
2250 return ret;
2251}
2252
2253static void __exit vfio_cleanup(void)
2254{
2255 WARN_ON(!list_empty(&vfio.group_list));
2256
2257#ifdef CONFIG_VFIO_NOIOMMU
2258 vfio_unregister_iommu_driver(&vfio_noiommu_ops);
2259#endif
2260 idr_destroy(&vfio.group_idr);
2261 cdev_del(&vfio.group_cdev);
2262 unregister_chrdev_region(vfio.group_devt, MINORMASK);
2263 class_destroy(vfio.class);
2264 vfio.class = NULL;
2265 misc_deregister(&vfio_dev);
2266}
2267
2268module_init(vfio_init);
2269module_exit(vfio_cleanup);
2270
2271MODULE_VERSION(DRIVER_VERSION);
2272MODULE_LICENSE("GPL v2");
2273MODULE_AUTHOR(DRIVER_AUTHOR);
2274MODULE_DESCRIPTION(DRIVER_DESC);
2275MODULE_ALIAS_MISCDEV(VFIO_MINOR);
2276MODULE_ALIAS("devname:vfio/vfio");
2277MODULE_SOFTDEP("post: vfio_iommu_type1 vfio_iommu_spapr_tce");