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1/*
2 * VFIO PCI interrupt handling
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/device.h>
17#include <linux/interrupt.h>
18#include <linux/eventfd.h>
19#include <linux/msi.h>
20#include <linux/pci.h>
21#include <linux/file.h>
22#include <linux/poll.h>
23#include <linux/vfio.h>
24#include <linux/wait.h>
25#include <linux/workqueue.h>
26#include <linux/slab.h>
27
28#include "vfio_pci_private.h"
29
30/*
31 * IRQfd - generic
32 */
33struct virqfd {
34	struct vfio_pci_device	*vdev;
35	struct eventfd_ctx	*eventfd;
36	int			(*handler)(struct vfio_pci_device *, void *);
37	void			(*thread)(struct vfio_pci_device *, void *);
38	void			*data;
39	struct work_struct	inject;
40	wait_queue_t		wait;
41	poll_table		pt;
42	struct work_struct	shutdown;
43	struct virqfd		**pvirqfd;
44};
45
46static struct workqueue_struct *vfio_irqfd_cleanup_wq;
47
48int __init vfio_pci_virqfd_init(void)
49{
50	vfio_irqfd_cleanup_wq =
51		create_singlethread_workqueue("vfio-irqfd-cleanup");
52	if (!vfio_irqfd_cleanup_wq)
53		return -ENOMEM;
54
55	return 0;
56}
57
58void vfio_pci_virqfd_exit(void)
59{
60	destroy_workqueue(vfio_irqfd_cleanup_wq);
61}
62
63static void virqfd_deactivate(struct virqfd *virqfd)
64{
65	queue_work(vfio_irqfd_cleanup_wq, &virqfd->shutdown);
66}
67
68static int virqfd_wakeup(wait_queue_t *wait, unsigned mode, int sync, void *key)
69{
70	struct virqfd *virqfd = container_of(wait, struct virqfd, wait);
71	unsigned long flags = (unsigned long)key;
72
73	if (flags & POLLIN) {
74		/* An event has been signaled, call function */
75		if ((!virqfd->handler ||
76		     virqfd->handler(virqfd->vdev, virqfd->data)) &&
77		    virqfd->thread)
78			schedule_work(&virqfd->inject);
79	}
80
81	if (flags & POLLHUP) {
82		unsigned long flags;
83		spin_lock_irqsave(&virqfd->vdev->irqlock, flags);
84
85		/*
86		 * The eventfd is closing, if the virqfd has not yet been
87		 * queued for release, as determined by testing whether the
88		 * vdev pointer to it is still valid, queue it now.  As
89		 * with kvm irqfds, we know we won't race against the virqfd
90		 * going away because we hold wqh->lock to get here.
91		 */
92		if (*(virqfd->pvirqfd) == virqfd) {
93			*(virqfd->pvirqfd) = NULL;
94			virqfd_deactivate(virqfd);
95		}
96
97		spin_unlock_irqrestore(&virqfd->vdev->irqlock, flags);
98	}
99
100	return 0;
101}
102
103static void virqfd_ptable_queue_proc(struct file *file,
104				     wait_queue_head_t *wqh, poll_table *pt)
105{
106	struct virqfd *virqfd = container_of(pt, struct virqfd, pt);
107	add_wait_queue(wqh, &virqfd->wait);
108}
109
110static void virqfd_shutdown(struct work_struct *work)
111{
112	struct virqfd *virqfd = container_of(work, struct virqfd, shutdown);
113	u64 cnt;
114
115	eventfd_ctx_remove_wait_queue(virqfd->eventfd, &virqfd->wait, &cnt);
116	flush_work(&virqfd->inject);
117	eventfd_ctx_put(virqfd->eventfd);
118
119	kfree(virqfd);
120}
121
122static void virqfd_inject(struct work_struct *work)
123{
124	struct virqfd *virqfd = container_of(work, struct virqfd, inject);
125	if (virqfd->thread)
126		virqfd->thread(virqfd->vdev, virqfd->data);
127}
128
129static int virqfd_enable(struct vfio_pci_device *vdev,
130			 int (*handler)(struct vfio_pci_device *, void *),
131			 void (*thread)(struct vfio_pci_device *, void *),
132			 void *data, struct virqfd **pvirqfd, int fd)
133{
134	struct fd irqfd;
135	struct eventfd_ctx *ctx;
136	struct virqfd *virqfd;
137	int ret = 0;
138	unsigned int events;
139
140	virqfd = kzalloc(sizeof(*virqfd), GFP_KERNEL);
141	if (!virqfd)
142		return -ENOMEM;
143
144	virqfd->pvirqfd = pvirqfd;
145	virqfd->vdev = vdev;
146	virqfd->handler = handler;
147	virqfd->thread = thread;
148	virqfd->data = data;
149
150	INIT_WORK(&virqfd->shutdown, virqfd_shutdown);
151	INIT_WORK(&virqfd->inject, virqfd_inject);
152
153	irqfd = fdget(fd);
154	if (!irqfd.file) {
155		ret = -EBADF;
156		goto err_fd;
157	}
158
159	ctx = eventfd_ctx_fileget(irqfd.file);
160	if (IS_ERR(ctx)) {
161		ret = PTR_ERR(ctx);
162		goto err_ctx;
163	}
164
165	virqfd->eventfd = ctx;
166
167	/*
168	 * virqfds can be released by closing the eventfd or directly
169	 * through ioctl.  These are both done through a workqueue, so
170	 * we update the pointer to the virqfd under lock to avoid
171	 * pushing multiple jobs to release the same virqfd.
172	 */
173	spin_lock_irq(&vdev->irqlock);
174
175	if (*pvirqfd) {
176		spin_unlock_irq(&vdev->irqlock);
177		ret = -EBUSY;
178		goto err_busy;
179	}
180	*pvirqfd = virqfd;
181
182	spin_unlock_irq(&vdev->irqlock);
183
184	/*
185	 * Install our own custom wake-up handling so we are notified via
186	 * a callback whenever someone signals the underlying eventfd.
187	 */
188	init_waitqueue_func_entry(&virqfd->wait, virqfd_wakeup);
189	init_poll_funcptr(&virqfd->pt, virqfd_ptable_queue_proc);
190
191	events = irqfd.file->f_op->poll(irqfd.file, &virqfd->pt);
192
193	/*
194	 * Check if there was an event already pending on the eventfd
195	 * before we registered and trigger it as if we didn't miss it.
196	 */
197	if (events & POLLIN) {
198		if ((!handler || handler(vdev, data)) && thread)
199			schedule_work(&virqfd->inject);
200	}
201
202	/*
203	 * Do not drop the file until the irqfd is fully initialized,
204	 * otherwise we might race against the POLLHUP.
205	 */
206	fdput(irqfd);
207
208	return 0;
209err_busy:
210	eventfd_ctx_put(ctx);
211err_ctx:
212	fdput(irqfd);
213err_fd:
214	kfree(virqfd);
215
216	return ret;
217}
218
219static void virqfd_disable(struct vfio_pci_device *vdev,
220			   struct virqfd **pvirqfd)
221{
222	unsigned long flags;
223
224	spin_lock_irqsave(&vdev->irqlock, flags);
225
226	if (*pvirqfd) {
227		virqfd_deactivate(*pvirqfd);
228		*pvirqfd = NULL;
229	}
230
231	spin_unlock_irqrestore(&vdev->irqlock, flags);
232
233	/*
234	 * Block until we know all outstanding shutdown jobs have completed.
235	 * Even if we don't queue the job, flush the wq to be sure it's
236	 * been released.
237	 */
238	flush_workqueue(vfio_irqfd_cleanup_wq);
239}
240
241/*
242 * INTx
243 */
244static void vfio_send_intx_eventfd(struct vfio_pci_device *vdev, void *unused)
245{
246	if (likely(is_intx(vdev) && !vdev->virq_disabled))
247		eventfd_signal(vdev->ctx[0].trigger, 1);
248}
249
250void vfio_pci_intx_mask(struct vfio_pci_device *vdev)
251{
252	struct pci_dev *pdev = vdev->pdev;
253	unsigned long flags;
254
255	spin_lock_irqsave(&vdev->irqlock, flags);
256
257	/*
258	 * Masking can come from interrupt, ioctl, or config space
259	 * via INTx disable.  The latter means this can get called
260	 * even when not using intx delivery.  In this case, just
261	 * try to have the physical bit follow the virtual bit.
262	 */
263	if (unlikely(!is_intx(vdev))) {
264		if (vdev->pci_2_3)
265			pci_intx(pdev, 0);
266	} else if (!vdev->ctx[0].masked) {
267		/*
268		 * Can't use check_and_mask here because we always want to
269		 * mask, not just when something is pending.
270		 */
271		if (vdev->pci_2_3)
272			pci_intx(pdev, 0);
273		else
274			disable_irq_nosync(pdev->irq);
275
276		vdev->ctx[0].masked = true;
277	}
278
279	spin_unlock_irqrestore(&vdev->irqlock, flags);
280}
281
282/*
283 * If this is triggered by an eventfd, we can't call eventfd_signal
284 * or else we'll deadlock on the eventfd wait queue.  Return >0 when
285 * a signal is necessary, which can then be handled via a work queue
286 * or directly depending on the caller.
287 */
288static int vfio_pci_intx_unmask_handler(struct vfio_pci_device *vdev,
289					void *unused)
290{
291	struct pci_dev *pdev = vdev->pdev;
292	unsigned long flags;
293	int ret = 0;
294
295	spin_lock_irqsave(&vdev->irqlock, flags);
296
297	/*
298	 * Unmasking comes from ioctl or config, so again, have the
299	 * physical bit follow the virtual even when not using INTx.
300	 */
301	if (unlikely(!is_intx(vdev))) {
302		if (vdev->pci_2_3)
303			pci_intx(pdev, 1);
304	} else if (vdev->ctx[0].masked && !vdev->virq_disabled) {
305		/*
306		 * A pending interrupt here would immediately trigger,
307		 * but we can avoid that overhead by just re-sending
308		 * the interrupt to the user.
309		 */
310		if (vdev->pci_2_3) {
311			if (!pci_check_and_unmask_intx(pdev))
312				ret = 1;
313		} else
314			enable_irq(pdev->irq);
315
316		vdev->ctx[0].masked = (ret > 0);
317	}
318
319	spin_unlock_irqrestore(&vdev->irqlock, flags);
320
321	return ret;
322}
323
324void vfio_pci_intx_unmask(struct vfio_pci_device *vdev)
325{
326	if (vfio_pci_intx_unmask_handler(vdev, NULL) > 0)
327		vfio_send_intx_eventfd(vdev, NULL);
328}
329
330static irqreturn_t vfio_intx_handler(int irq, void *dev_id)
331{
332	struct vfio_pci_device *vdev = dev_id;
333	unsigned long flags;
334	int ret = IRQ_NONE;
335
336	spin_lock_irqsave(&vdev->irqlock, flags);
337
338	if (!vdev->pci_2_3) {
339		disable_irq_nosync(vdev->pdev->irq);
340		vdev->ctx[0].masked = true;
341		ret = IRQ_HANDLED;
342	} else if (!vdev->ctx[0].masked &&  /* may be shared */
343		   pci_check_and_mask_intx(vdev->pdev)) {
344		vdev->ctx[0].masked = true;
345		ret = IRQ_HANDLED;
346	}
347
348	spin_unlock_irqrestore(&vdev->irqlock, flags);
349
350	if (ret == IRQ_HANDLED)
351		vfio_send_intx_eventfd(vdev, NULL);
352
353	return ret;
354}
355
356static int vfio_intx_enable(struct vfio_pci_device *vdev)
357{
358	if (!is_irq_none(vdev))
359		return -EINVAL;
360
361	if (!vdev->pdev->irq)
362		return -ENODEV;
363
364	vdev->ctx = kzalloc(sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL);
365	if (!vdev->ctx)
366		return -ENOMEM;
367
368	vdev->num_ctx = 1;
369
370	/*
371	 * If the virtual interrupt is masked, restore it.  Devices
372	 * supporting DisINTx can be masked at the hardware level
373	 * here, non-PCI-2.3 devices will have to wait until the
374	 * interrupt is enabled.
375	 */
376	vdev->ctx[0].masked = vdev->virq_disabled;
377	if (vdev->pci_2_3)
378		pci_intx(vdev->pdev, !vdev->ctx[0].masked);
379
380	vdev->irq_type = VFIO_PCI_INTX_IRQ_INDEX;
381
382	return 0;
383}
384
385static int vfio_intx_set_signal(struct vfio_pci_device *vdev, int fd)
386{
387	struct pci_dev *pdev = vdev->pdev;
388	unsigned long irqflags = IRQF_SHARED;
389	struct eventfd_ctx *trigger;
390	unsigned long flags;
391	int ret;
392
393	if (vdev->ctx[0].trigger) {
394		free_irq(pdev->irq, vdev);
395		kfree(vdev->ctx[0].name);
396		eventfd_ctx_put(vdev->ctx[0].trigger);
397		vdev->ctx[0].trigger = NULL;
398	}
399
400	if (fd < 0) /* Disable only */
401		return 0;
402
403	vdev->ctx[0].name = kasprintf(GFP_KERNEL, "vfio-intx(%s)",
404				      pci_name(pdev));
405	if (!vdev->ctx[0].name)
406		return -ENOMEM;
407
408	trigger = eventfd_ctx_fdget(fd);
409	if (IS_ERR(trigger)) {
410		kfree(vdev->ctx[0].name);
411		return PTR_ERR(trigger);
412	}
413
414	vdev->ctx[0].trigger = trigger;
415
416	if (!vdev->pci_2_3)
417		irqflags = 0;
418
419	ret = request_irq(pdev->irq, vfio_intx_handler,
420			  irqflags, vdev->ctx[0].name, vdev);
421	if (ret) {
422		vdev->ctx[0].trigger = NULL;
423		kfree(vdev->ctx[0].name);
424		eventfd_ctx_put(trigger);
425		return ret;
426	}
427
428	/*
429	 * INTx disable will stick across the new irq setup,
430	 * disable_irq won't.
431	 */
432	spin_lock_irqsave(&vdev->irqlock, flags);
433	if (!vdev->pci_2_3 && vdev->ctx[0].masked)
434		disable_irq_nosync(pdev->irq);
435	spin_unlock_irqrestore(&vdev->irqlock, flags);
436
437	return 0;
438}
439
440static void vfio_intx_disable(struct vfio_pci_device *vdev)
441{
442	vfio_intx_set_signal(vdev, -1);
443	virqfd_disable(vdev, &vdev->ctx[0].unmask);
444	virqfd_disable(vdev, &vdev->ctx[0].mask);
445	vdev->irq_type = VFIO_PCI_NUM_IRQS;
446	vdev->num_ctx = 0;
447	kfree(vdev->ctx);
448}
449
450/*
451 * MSI/MSI-X
452 */
453static irqreturn_t vfio_msihandler(int irq, void *arg)
454{
455	struct eventfd_ctx *trigger = arg;
456
457	eventfd_signal(trigger, 1);
458	return IRQ_HANDLED;
459}
460
461static int vfio_msi_enable(struct vfio_pci_device *vdev, int nvec, bool msix)
462{
463	struct pci_dev *pdev = vdev->pdev;
464	int ret;
465
466	if (!is_irq_none(vdev))
467		return -EINVAL;
468
469	vdev->ctx = kzalloc(nvec * sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL);
470	if (!vdev->ctx)
471		return -ENOMEM;
472
473	if (msix) {
474		int i;
475
476		vdev->msix = kzalloc(nvec * sizeof(struct msix_entry),
477				     GFP_KERNEL);
478		if (!vdev->msix) {
479			kfree(vdev->ctx);
480			return -ENOMEM;
481		}
482
483		for (i = 0; i < nvec; i++)
484			vdev->msix[i].entry = i;
485
486		ret = pci_enable_msix_range(pdev, vdev->msix, 1, nvec);
487		if (ret < nvec) {
488			if (ret > 0)
489				pci_disable_msix(pdev);
490			kfree(vdev->msix);
491			kfree(vdev->ctx);
492			return ret;
493		}
494	} else {
495		ret = pci_enable_msi_range(pdev, 1, nvec);
496		if (ret < nvec) {
497			if (ret > 0)
498				pci_disable_msi(pdev);
499			kfree(vdev->ctx);
500			return ret;
501		}
502	}
503
504	vdev->num_ctx = nvec;
505	vdev->irq_type = msix ? VFIO_PCI_MSIX_IRQ_INDEX :
506				VFIO_PCI_MSI_IRQ_INDEX;
507
508	if (!msix) {
509		/*
510		 * Compute the virtual hardware field for max msi vectors -
511		 * it is the log base 2 of the number of vectors.
512		 */
513		vdev->msi_qmax = fls(nvec * 2 - 1) - 1;
514	}
515
516	return 0;
517}
518
519static int vfio_msi_set_vector_signal(struct vfio_pci_device *vdev,
520				      int vector, int fd, bool msix)
521{
522	struct pci_dev *pdev = vdev->pdev;
523	int irq = msix ? vdev->msix[vector].vector : pdev->irq + vector;
524	char *name = msix ? "vfio-msix" : "vfio-msi";
525	struct eventfd_ctx *trigger;
526	int ret;
527
528	if (vector >= vdev->num_ctx)
529		return -EINVAL;
530
531	if (vdev->ctx[vector].trigger) {
532		free_irq(irq, vdev->ctx[vector].trigger);
533		kfree(vdev->ctx[vector].name);
534		eventfd_ctx_put(vdev->ctx[vector].trigger);
535		vdev->ctx[vector].trigger = NULL;
536	}
537
538	if (fd < 0)
539		return 0;
540
541	vdev->ctx[vector].name = kasprintf(GFP_KERNEL, "%s[%d](%s)",
542					   name, vector, pci_name(pdev));
543	if (!vdev->ctx[vector].name)
544		return -ENOMEM;
545
546	trigger = eventfd_ctx_fdget(fd);
547	if (IS_ERR(trigger)) {
548		kfree(vdev->ctx[vector].name);
549		return PTR_ERR(trigger);
550	}
551
552	/*
553	 * The MSIx vector table resides in device memory which may be cleared
554	 * via backdoor resets. We don't allow direct access to the vector
555	 * table so even if a userspace driver attempts to save/restore around
556	 * such a reset it would be unsuccessful. To avoid this, restore the
557	 * cached value of the message prior to enabling.
558	 */
559	if (msix) {
560		struct msi_msg msg;
561
562		get_cached_msi_msg(irq, &msg);
563		write_msi_msg(irq, &msg);
564	}
565
566	ret = request_irq(irq, vfio_msihandler, 0,
567			  vdev->ctx[vector].name, trigger);
568	if (ret) {
569		kfree(vdev->ctx[vector].name);
570		eventfd_ctx_put(trigger);
571		return ret;
572	}
573
574	vdev->ctx[vector].trigger = trigger;
575
576	return 0;
577}
578
579static int vfio_msi_set_block(struct vfio_pci_device *vdev, unsigned start,
580			      unsigned count, int32_t *fds, bool msix)
581{
582	int i, j, ret = 0;
583
584	if (start + count > vdev->num_ctx)
585		return -EINVAL;
586
587	for (i = 0, j = start; i < count && !ret; i++, j++) {
588		int fd = fds ? fds[i] : -1;
589		ret = vfio_msi_set_vector_signal(vdev, j, fd, msix);
590	}
591
592	if (ret) {
593		for (--j; j >= start; j--)
594			vfio_msi_set_vector_signal(vdev, j, -1, msix);
595	}
596
597	return ret;
598}
599
600static void vfio_msi_disable(struct vfio_pci_device *vdev, bool msix)
601{
602	struct pci_dev *pdev = vdev->pdev;
603	int i;
604
605	vfio_msi_set_block(vdev, 0, vdev->num_ctx, NULL, msix);
606
607	for (i = 0; i < vdev->num_ctx; i++) {
608		virqfd_disable(vdev, &vdev->ctx[i].unmask);
609		virqfd_disable(vdev, &vdev->ctx[i].mask);
610	}
611
612	if (msix) {
613		pci_disable_msix(vdev->pdev);
614		kfree(vdev->msix);
615	} else
616		pci_disable_msi(pdev);
617
618	vdev->irq_type = VFIO_PCI_NUM_IRQS;
619	vdev->num_ctx = 0;
620	kfree(vdev->ctx);
621}
622
623/*
624 * IOCTL support
625 */
626static int vfio_pci_set_intx_unmask(struct vfio_pci_device *vdev,
627				    unsigned index, unsigned start,
628				    unsigned count, uint32_t flags, void *data)
629{
630	if (!is_intx(vdev) || start != 0 || count != 1)
631		return -EINVAL;
632
633	if (flags & VFIO_IRQ_SET_DATA_NONE) {
634		vfio_pci_intx_unmask(vdev);
635	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
636		uint8_t unmask = *(uint8_t *)data;
637		if (unmask)
638			vfio_pci_intx_unmask(vdev);
639	} else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
640		int32_t fd = *(int32_t *)data;
641		if (fd >= 0)
642			return virqfd_enable(vdev, vfio_pci_intx_unmask_handler,
643					     vfio_send_intx_eventfd, NULL,
644					     &vdev->ctx[0].unmask, fd);
645
646		virqfd_disable(vdev, &vdev->ctx[0].unmask);
647	}
648
649	return 0;
650}
651
652static int vfio_pci_set_intx_mask(struct vfio_pci_device *vdev,
653				  unsigned index, unsigned start,
654				  unsigned count, uint32_t flags, void *data)
655{
656	if (!is_intx(vdev) || start != 0 || count != 1)
657		return -EINVAL;
658
659	if (flags & VFIO_IRQ_SET_DATA_NONE) {
660		vfio_pci_intx_mask(vdev);
661	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
662		uint8_t mask = *(uint8_t *)data;
663		if (mask)
664			vfio_pci_intx_mask(vdev);
665	} else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
666		return -ENOTTY; /* XXX implement me */
667	}
668
669	return 0;
670}
671
672static int vfio_pci_set_intx_trigger(struct vfio_pci_device *vdev,
673				     unsigned index, unsigned start,
674				     unsigned count, uint32_t flags, void *data)
675{
676	if (is_intx(vdev) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
677		vfio_intx_disable(vdev);
678		return 0;
679	}
680
681	if (!(is_intx(vdev) || is_irq_none(vdev)) || start != 0 || count != 1)
682		return -EINVAL;
683
684	if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
685		int32_t fd = *(int32_t *)data;
686		int ret;
687
688		if (is_intx(vdev))
689			return vfio_intx_set_signal(vdev, fd);
690
691		ret = vfio_intx_enable(vdev);
692		if (ret)
693			return ret;
694
695		ret = vfio_intx_set_signal(vdev, fd);
696		if (ret)
697			vfio_intx_disable(vdev);
698
699		return ret;
700	}
701
702	if (!is_intx(vdev))
703		return -EINVAL;
704
705	if (flags & VFIO_IRQ_SET_DATA_NONE) {
706		vfio_send_intx_eventfd(vdev, NULL);
707	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
708		uint8_t trigger = *(uint8_t *)data;
709		if (trigger)
710			vfio_send_intx_eventfd(vdev, NULL);
711	}
712	return 0;
713}
714
715static int vfio_pci_set_msi_trigger(struct vfio_pci_device *vdev,
716				    unsigned index, unsigned start,
717				    unsigned count, uint32_t flags, void *data)
718{
719	int i;
720	bool msix = (index == VFIO_PCI_MSIX_IRQ_INDEX) ? true : false;
721
722	if (irq_is(vdev, index) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
723		vfio_msi_disable(vdev, msix);
724		return 0;
725	}
726
727	if (!(irq_is(vdev, index) || is_irq_none(vdev)))
728		return -EINVAL;
729
730	if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
731		int32_t *fds = data;
732		int ret;
733
734		if (vdev->irq_type == index)
735			return vfio_msi_set_block(vdev, start, count,
736						  fds, msix);
737
738		ret = vfio_msi_enable(vdev, start + count, msix);
739		if (ret)
740			return ret;
741
742		ret = vfio_msi_set_block(vdev, start, count, fds, msix);
743		if (ret)
744			vfio_msi_disable(vdev, msix);
745
746		return ret;
747	}
748
749	if (!irq_is(vdev, index) || start + count > vdev->num_ctx)
750		return -EINVAL;
751
752	for (i = start; i < start + count; i++) {
753		if (!vdev->ctx[i].trigger)
754			continue;
755		if (flags & VFIO_IRQ_SET_DATA_NONE) {
756			eventfd_signal(vdev->ctx[i].trigger, 1);
757		} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
758			uint8_t *bools = data;
759			if (bools[i - start])
760				eventfd_signal(vdev->ctx[i].trigger, 1);
761		}
762	}
763	return 0;
764}
765
766static int vfio_pci_set_err_trigger(struct vfio_pci_device *vdev,
767				    unsigned index, unsigned start,
768				    unsigned count, uint32_t flags, void *data)
769{
770	int32_t fd = *(int32_t *)data;
771
772	if ((index != VFIO_PCI_ERR_IRQ_INDEX) ||
773	    !(flags & VFIO_IRQ_SET_DATA_TYPE_MASK))
774		return -EINVAL;
775
776	/* DATA_NONE/DATA_BOOL enables loopback testing */
777	if (flags & VFIO_IRQ_SET_DATA_NONE) {
778		if (vdev->err_trigger)
779			eventfd_signal(vdev->err_trigger, 1);
780		return 0;
781	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
782		uint8_t trigger = *(uint8_t *)data;
783		if (trigger && vdev->err_trigger)
784			eventfd_signal(vdev->err_trigger, 1);
785		return 0;
786	}
787
788	/* Handle SET_DATA_EVENTFD */
789	if (fd == -1) {
790		if (vdev->err_trigger)
791			eventfd_ctx_put(vdev->err_trigger);
792		vdev->err_trigger = NULL;
793		return 0;
794	} else if (fd >= 0) {
795		struct eventfd_ctx *efdctx;
796		efdctx = eventfd_ctx_fdget(fd);
797		if (IS_ERR(efdctx))
798			return PTR_ERR(efdctx);
799		if (vdev->err_trigger)
800			eventfd_ctx_put(vdev->err_trigger);
801		vdev->err_trigger = efdctx;
802		return 0;
803	} else
804		return -EINVAL;
805}
806int vfio_pci_set_irqs_ioctl(struct vfio_pci_device *vdev, uint32_t flags,
807			    unsigned index, unsigned start, unsigned count,
808			    void *data)
809{
810	int (*func)(struct vfio_pci_device *vdev, unsigned index,
811		    unsigned start, unsigned count, uint32_t flags,
812		    void *data) = NULL;
813
814	switch (index) {
815	case VFIO_PCI_INTX_IRQ_INDEX:
816		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
817		case VFIO_IRQ_SET_ACTION_MASK:
818			func = vfio_pci_set_intx_mask;
819			break;
820		case VFIO_IRQ_SET_ACTION_UNMASK:
821			func = vfio_pci_set_intx_unmask;
822			break;
823		case VFIO_IRQ_SET_ACTION_TRIGGER:
824			func = vfio_pci_set_intx_trigger;
825			break;
826		}
827		break;
828	case VFIO_PCI_MSI_IRQ_INDEX:
829	case VFIO_PCI_MSIX_IRQ_INDEX:
830		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
831		case VFIO_IRQ_SET_ACTION_MASK:
832		case VFIO_IRQ_SET_ACTION_UNMASK:
833			/* XXX Need masking support exported */
834			break;
835		case VFIO_IRQ_SET_ACTION_TRIGGER:
836			func = vfio_pci_set_msi_trigger;
837			break;
838		}
839		break;
840	case VFIO_PCI_ERR_IRQ_INDEX:
841		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
842		case VFIO_IRQ_SET_ACTION_TRIGGER:
843			if (pci_is_pcie(vdev->pdev))
844				func = vfio_pci_set_err_trigger;
845			break;
846		}
847	}
848
849	if (!func)
850		return -ENOTTY;
851
852	return func(vdev, index, start, count, flags, data);
853}
854