vfio_pci_intrs.c revision 94cccde648d32abe61e2d0d1b18178f3027f1a78
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/pci.h>
20#include <linux/file.h>
21#include <linux/poll.h>
22#include <linux/vfio.h>
23#include <linux/wait.h>
24#include <linux/workqueue.h>
25#include <linux/slab.h>
26
27#include "vfio_pci_private.h"
28
29/*
30 * IRQfd - generic
31 */
32struct virqfd {
33	struct vfio_pci_device	*vdev;
34	struct eventfd_ctx	*eventfd;
35	int			(*handler)(struct vfio_pci_device *, void *);
36	void			(*thread)(struct vfio_pci_device *, void *);
37	void			*data;
38	struct work_struct	inject;
39	wait_queue_t		wait;
40	poll_table		pt;
41	struct work_struct	shutdown;
42	struct virqfd		**pvirqfd;
43};
44
45static struct workqueue_struct *vfio_irqfd_cleanup_wq;
46
47int __init vfio_pci_virqfd_init(void)
48{
49	vfio_irqfd_cleanup_wq =
50		create_singlethread_workqueue("vfio-irqfd-cleanup");
51	if (!vfio_irqfd_cleanup_wq)
52		return -ENOMEM;
53
54	return 0;
55}
56
57void vfio_pci_virqfd_exit(void)
58{
59	destroy_workqueue(vfio_irqfd_cleanup_wq);
60}
61
62static void virqfd_deactivate(struct virqfd *virqfd)
63{
64	queue_work(vfio_irqfd_cleanup_wq, &virqfd->shutdown);
65}
66
67static int virqfd_wakeup(wait_queue_t *wait, unsigned mode, int sync, void *key)
68{
69	struct virqfd *virqfd = container_of(wait, struct virqfd, wait);
70	unsigned long flags = (unsigned long)key;
71
72	if (flags & POLLIN) {
73		/* An event has been signaled, call function */
74		if ((!virqfd->handler ||
75		     virqfd->handler(virqfd->vdev, virqfd->data)) &&
76		    virqfd->thread)
77			schedule_work(&virqfd->inject);
78	}
79
80	if (flags & POLLHUP) {
81		unsigned long flags;
82		spin_lock_irqsave(&virqfd->vdev->irqlock, flags);
83
84		/*
85		 * The eventfd is closing, if the virqfd has not yet been
86		 * queued for release, as determined by testing whether the
87		 * vdev pointer to it is still valid, queue it now.  As
88		 * with kvm irqfds, we know we won't race against the virqfd
89		 * going away because we hold wqh->lock to get here.
90		 */
91		if (*(virqfd->pvirqfd) == virqfd) {
92			*(virqfd->pvirqfd) = NULL;
93			virqfd_deactivate(virqfd);
94		}
95
96		spin_unlock_irqrestore(&virqfd->vdev->irqlock, flags);
97	}
98
99	return 0;
100}
101
102static void virqfd_ptable_queue_proc(struct file *file,
103				     wait_queue_head_t *wqh, poll_table *pt)
104{
105	struct virqfd *virqfd = container_of(pt, struct virqfd, pt);
106	add_wait_queue(wqh, &virqfd->wait);
107}
108
109static void virqfd_shutdown(struct work_struct *work)
110{
111	struct virqfd *virqfd = container_of(work, struct virqfd, shutdown);
112	u64 cnt;
113
114	eventfd_ctx_remove_wait_queue(virqfd->eventfd, &virqfd->wait, &cnt);
115	flush_work(&virqfd->inject);
116	eventfd_ctx_put(virqfd->eventfd);
117
118	kfree(virqfd);
119}
120
121static void virqfd_inject(struct work_struct *work)
122{
123	struct virqfd *virqfd = container_of(work, struct virqfd, inject);
124	if (virqfd->thread)
125		virqfd->thread(virqfd->vdev, virqfd->data);
126}
127
128static int virqfd_enable(struct vfio_pci_device *vdev,
129			 int (*handler)(struct vfio_pci_device *, void *),
130			 void (*thread)(struct vfio_pci_device *, void *),
131			 void *data, struct virqfd **pvirqfd, int fd)
132{
133	struct fd irqfd;
134	struct eventfd_ctx *ctx;
135	struct virqfd *virqfd;
136	int ret = 0;
137	unsigned int events;
138
139	virqfd = kzalloc(sizeof(*virqfd), GFP_KERNEL);
140	if (!virqfd)
141		return -ENOMEM;
142
143	virqfd->pvirqfd = pvirqfd;
144	virqfd->vdev = vdev;
145	virqfd->handler = handler;
146	virqfd->thread = thread;
147	virqfd->data = data;
148
149	INIT_WORK(&virqfd->shutdown, virqfd_shutdown);
150	INIT_WORK(&virqfd->inject, virqfd_inject);
151
152	irqfd = fdget(fd);
153	if (!irqfd.file) {
154		ret = -EBADF;
155		goto err_fd;
156	}
157
158	ctx = eventfd_ctx_fileget(irqfd.file);
159	if (IS_ERR(ctx)) {
160		ret = PTR_ERR(ctx);
161		goto err_ctx;
162	}
163
164	virqfd->eventfd = ctx;
165
166	/*
167	 * virqfds can be released by closing the eventfd or directly
168	 * through ioctl.  These are both done through a workqueue, so
169	 * we update the pointer to the virqfd under lock to avoid
170	 * pushing multiple jobs to release the same virqfd.
171	 */
172	spin_lock_irq(&vdev->irqlock);
173
174	if (*pvirqfd) {
175		spin_unlock_irq(&vdev->irqlock);
176		ret = -EBUSY;
177		goto err_busy;
178	}
179	*pvirqfd = virqfd;
180
181	spin_unlock_irq(&vdev->irqlock);
182
183	/*
184	 * Install our own custom wake-up handling so we are notified via
185	 * a callback whenever someone signals the underlying eventfd.
186	 */
187	init_waitqueue_func_entry(&virqfd->wait, virqfd_wakeup);
188	init_poll_funcptr(&virqfd->pt, virqfd_ptable_queue_proc);
189
190	events = irqfd.file->f_op->poll(irqfd.file, &virqfd->pt);
191
192	/*
193	 * Check if there was an event already pending on the eventfd
194	 * before we registered and trigger it as if we didn't miss it.
195	 */
196	if (events & POLLIN) {
197		if ((!handler || handler(vdev, data)) && thread)
198			schedule_work(&virqfd->inject);
199	}
200
201	/*
202	 * Do not drop the file until the irqfd is fully initialized,
203	 * otherwise we might race against the POLLHUP.
204	 */
205	fdput(irqfd);
206
207	return 0;
208err_busy:
209	eventfd_ctx_put(ctx);
210err_ctx:
211	fdput(irqfd);
212err_fd:
213	kfree(virqfd);
214
215	return ret;
216}
217
218static void virqfd_disable(struct vfio_pci_device *vdev,
219			   struct virqfd **pvirqfd)
220{
221	unsigned long flags;
222
223	spin_lock_irqsave(&vdev->irqlock, flags);
224
225	if (*pvirqfd) {
226		virqfd_deactivate(*pvirqfd);
227		*pvirqfd = NULL;
228	}
229
230	spin_unlock_irqrestore(&vdev->irqlock, flags);
231
232	/*
233	 * Block until we know all outstanding shutdown jobs have completed.
234	 * Even if we don't queue the job, flush the wq to be sure it's
235	 * been released.
236	 */
237	flush_workqueue(vfio_irqfd_cleanup_wq);
238}
239
240/*
241 * INTx
242 */
243static void vfio_send_intx_eventfd(struct vfio_pci_device *vdev, void *unused)
244{
245	if (likely(is_intx(vdev) && !vdev->virq_disabled))
246		eventfd_signal(vdev->ctx[0].trigger, 1);
247}
248
249void vfio_pci_intx_mask(struct vfio_pci_device *vdev)
250{
251	struct pci_dev *pdev = vdev->pdev;
252	unsigned long flags;
253
254	spin_lock_irqsave(&vdev->irqlock, flags);
255
256	/*
257	 * Masking can come from interrupt, ioctl, or config space
258	 * via INTx disable.  The latter means this can get called
259	 * even when not using intx delivery.  In this case, just
260	 * try to have the physical bit follow the virtual bit.
261	 */
262	if (unlikely(!is_intx(vdev))) {
263		if (vdev->pci_2_3)
264			pci_intx(pdev, 0);
265	} else if (!vdev->ctx[0].masked) {
266		/*
267		 * Can't use check_and_mask here because we always want to
268		 * mask, not just when something is pending.
269		 */
270		if (vdev->pci_2_3)
271			pci_intx(pdev, 0);
272		else
273			disable_irq_nosync(pdev->irq);
274
275		vdev->ctx[0].masked = true;
276	}
277
278	spin_unlock_irqrestore(&vdev->irqlock, flags);
279}
280
281/*
282 * If this is triggered by an eventfd, we can't call eventfd_signal
283 * or else we'll deadlock on the eventfd wait queue.  Return >0 when
284 * a signal is necessary, which can then be handled via a work queue
285 * or directly depending on the caller.
286 */
287static int vfio_pci_intx_unmask_handler(struct vfio_pci_device *vdev,
288					void *unused)
289{
290	struct pci_dev *pdev = vdev->pdev;
291	unsigned long flags;
292	int ret = 0;
293
294	spin_lock_irqsave(&vdev->irqlock, flags);
295
296	/*
297	 * Unmasking comes from ioctl or config, so again, have the
298	 * physical bit follow the virtual even when not using INTx.
299	 */
300	if (unlikely(!is_intx(vdev))) {
301		if (vdev->pci_2_3)
302			pci_intx(pdev, 1);
303	} else if (vdev->ctx[0].masked && !vdev->virq_disabled) {
304		/*
305		 * A pending interrupt here would immediately trigger,
306		 * but we can avoid that overhead by just re-sending
307		 * the interrupt to the user.
308		 */
309		if (vdev->pci_2_3) {
310			if (!pci_check_and_unmask_intx(pdev))
311				ret = 1;
312		} else
313			enable_irq(pdev->irq);
314
315		vdev->ctx[0].masked = (ret > 0);
316	}
317
318	spin_unlock_irqrestore(&vdev->irqlock, flags);
319
320	return ret;
321}
322
323void vfio_pci_intx_unmask(struct vfio_pci_device *vdev)
324{
325	if (vfio_pci_intx_unmask_handler(vdev, NULL) > 0)
326		vfio_send_intx_eventfd(vdev, NULL);
327}
328
329static irqreturn_t vfio_intx_handler(int irq, void *dev_id)
330{
331	struct vfio_pci_device *vdev = dev_id;
332	unsigned long flags;
333	int ret = IRQ_NONE;
334
335	spin_lock_irqsave(&vdev->irqlock, flags);
336
337	if (!vdev->pci_2_3) {
338		disable_irq_nosync(vdev->pdev->irq);
339		vdev->ctx[0].masked = true;
340		ret = IRQ_HANDLED;
341	} else if (!vdev->ctx[0].masked &&  /* may be shared */
342		   pci_check_and_mask_intx(vdev->pdev)) {
343		vdev->ctx[0].masked = true;
344		ret = IRQ_HANDLED;
345	}
346
347	spin_unlock_irqrestore(&vdev->irqlock, flags);
348
349	if (ret == IRQ_HANDLED)
350		vfio_send_intx_eventfd(vdev, NULL);
351
352	return ret;
353}
354
355static int vfio_intx_enable(struct vfio_pci_device *vdev)
356{
357	if (!is_irq_none(vdev))
358		return -EINVAL;
359
360	if (!vdev->pdev->irq)
361		return -ENODEV;
362
363	vdev->ctx = kzalloc(sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL);
364	if (!vdev->ctx)
365		return -ENOMEM;
366
367	vdev->num_ctx = 1;
368
369	/*
370	 * If the virtual interrupt is masked, restore it.  Devices
371	 * supporting DisINTx can be masked at the hardware level
372	 * here, non-PCI-2.3 devices will have to wait until the
373	 * interrupt is enabled.
374	 */
375	vdev->ctx[0].masked = vdev->virq_disabled;
376	if (vdev->pci_2_3)
377		pci_intx(vdev->pdev, !vdev->ctx[0].masked);
378
379	vdev->irq_type = VFIO_PCI_INTX_IRQ_INDEX;
380
381	return 0;
382}
383
384static int vfio_intx_set_signal(struct vfio_pci_device *vdev, int fd)
385{
386	struct pci_dev *pdev = vdev->pdev;
387	unsigned long irqflags = IRQF_SHARED;
388	struct eventfd_ctx *trigger;
389	unsigned long flags;
390	int ret;
391
392	if (vdev->ctx[0].trigger) {
393		free_irq(pdev->irq, vdev);
394		kfree(vdev->ctx[0].name);
395		eventfd_ctx_put(vdev->ctx[0].trigger);
396		vdev->ctx[0].trigger = NULL;
397	}
398
399	if (fd < 0) /* Disable only */
400		return 0;
401
402	vdev->ctx[0].name = kasprintf(GFP_KERNEL, "vfio-intx(%s)",
403				      pci_name(pdev));
404	if (!vdev->ctx[0].name)
405		return -ENOMEM;
406
407	trigger = eventfd_ctx_fdget(fd);
408	if (IS_ERR(trigger)) {
409		kfree(vdev->ctx[0].name);
410		return PTR_ERR(trigger);
411	}
412
413	vdev->ctx[0].trigger = trigger;
414
415	if (!vdev->pci_2_3)
416		irqflags = 0;
417
418	ret = request_irq(pdev->irq, vfio_intx_handler,
419			  irqflags, vdev->ctx[0].name, vdev);
420	if (ret) {
421		vdev->ctx[0].trigger = NULL;
422		kfree(vdev->ctx[0].name);
423		eventfd_ctx_put(trigger);
424		return ret;
425	}
426
427	/*
428	 * INTx disable will stick across the new irq setup,
429	 * disable_irq won't.
430	 */
431	spin_lock_irqsave(&vdev->irqlock, flags);
432	if (!vdev->pci_2_3 && vdev->ctx[0].masked)
433		disable_irq_nosync(pdev->irq);
434	spin_unlock_irqrestore(&vdev->irqlock, flags);
435
436	return 0;
437}
438
439static void vfio_intx_disable(struct vfio_pci_device *vdev)
440{
441	vfio_intx_set_signal(vdev, -1);
442	virqfd_disable(vdev, &vdev->ctx[0].unmask);
443	virqfd_disable(vdev, &vdev->ctx[0].mask);
444	vdev->irq_type = VFIO_PCI_NUM_IRQS;
445	vdev->num_ctx = 0;
446	kfree(vdev->ctx);
447}
448
449/*
450 * MSI/MSI-X
451 */
452static irqreturn_t vfio_msihandler(int irq, void *arg)
453{
454	struct eventfd_ctx *trigger = arg;
455
456	eventfd_signal(trigger, 1);
457	return IRQ_HANDLED;
458}
459
460static int vfio_msi_enable(struct vfio_pci_device *vdev, int nvec, bool msix)
461{
462	struct pci_dev *pdev = vdev->pdev;
463	int ret;
464
465	if (!is_irq_none(vdev))
466		return -EINVAL;
467
468	vdev->ctx = kzalloc(nvec * sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL);
469	if (!vdev->ctx)
470		return -ENOMEM;
471
472	if (msix) {
473		int i;
474
475		vdev->msix = kzalloc(nvec * sizeof(struct msix_entry),
476				     GFP_KERNEL);
477		if (!vdev->msix) {
478			kfree(vdev->ctx);
479			return -ENOMEM;
480		}
481
482		for (i = 0; i < nvec; i++)
483			vdev->msix[i].entry = i;
484
485		ret = pci_enable_msix_range(pdev, vdev->msix, 1, nvec);
486		if (ret < nvec) {
487			if (ret > 0)
488				pci_disable_msix(pdev);
489			kfree(vdev->msix);
490			kfree(vdev->ctx);
491			return ret;
492		}
493	} else {
494		ret = pci_enable_msi_range(pdev, 1, nvec);
495		if (ret < nvec) {
496			if (ret > 0)
497				pci_disable_msi(pdev);
498			kfree(vdev->ctx);
499			return ret;
500		}
501	}
502
503	vdev->num_ctx = nvec;
504	vdev->irq_type = msix ? VFIO_PCI_MSIX_IRQ_INDEX :
505				VFIO_PCI_MSI_IRQ_INDEX;
506
507	if (!msix) {
508		/*
509		 * Compute the virtual hardware field for max msi vectors -
510		 * it is the log base 2 of the number of vectors.
511		 */
512		vdev->msi_qmax = fls(nvec * 2 - 1) - 1;
513	}
514
515	return 0;
516}
517
518static int vfio_msi_set_vector_signal(struct vfio_pci_device *vdev,
519				      int vector, int fd, bool msix)
520{
521	struct pci_dev *pdev = vdev->pdev;
522	int irq = msix ? vdev->msix[vector].vector : pdev->irq + vector;
523	char *name = msix ? "vfio-msix" : "vfio-msi";
524	struct eventfd_ctx *trigger;
525	int ret;
526
527	if (vector >= vdev->num_ctx)
528		return -EINVAL;
529
530	if (vdev->ctx[vector].trigger) {
531		free_irq(irq, vdev->ctx[vector].trigger);
532		kfree(vdev->ctx[vector].name);
533		eventfd_ctx_put(vdev->ctx[vector].trigger);
534		vdev->ctx[vector].trigger = NULL;
535	}
536
537	if (fd < 0)
538		return 0;
539
540	vdev->ctx[vector].name = kasprintf(GFP_KERNEL, "%s[%d](%s)",
541					   name, vector, pci_name(pdev));
542	if (!vdev->ctx[vector].name)
543		return -ENOMEM;
544
545	trigger = eventfd_ctx_fdget(fd);
546	if (IS_ERR(trigger)) {
547		kfree(vdev->ctx[vector].name);
548		return PTR_ERR(trigger);
549	}
550
551	ret = request_irq(irq, vfio_msihandler, 0,
552			  vdev->ctx[vector].name, trigger);
553	if (ret) {
554		kfree(vdev->ctx[vector].name);
555		eventfd_ctx_put(trigger);
556		return ret;
557	}
558
559	vdev->ctx[vector].trigger = trigger;
560
561	return 0;
562}
563
564static int vfio_msi_set_block(struct vfio_pci_device *vdev, unsigned start,
565			      unsigned count, int32_t *fds, bool msix)
566{
567	int i, j, ret = 0;
568
569	if (start + count > vdev->num_ctx)
570		return -EINVAL;
571
572	for (i = 0, j = start; i < count && !ret; i++, j++) {
573		int fd = fds ? fds[i] : -1;
574		ret = vfio_msi_set_vector_signal(vdev, j, fd, msix);
575	}
576
577	if (ret) {
578		for (--j; j >= start; j--)
579			vfio_msi_set_vector_signal(vdev, j, -1, msix);
580	}
581
582	return ret;
583}
584
585static void vfio_msi_disable(struct vfio_pci_device *vdev, bool msix)
586{
587	struct pci_dev *pdev = vdev->pdev;
588	int i;
589
590	vfio_msi_set_block(vdev, 0, vdev->num_ctx, NULL, msix);
591
592	for (i = 0; i < vdev->num_ctx; i++) {
593		virqfd_disable(vdev, &vdev->ctx[i].unmask);
594		virqfd_disable(vdev, &vdev->ctx[i].mask);
595	}
596
597	if (msix) {
598		pci_disable_msix(vdev->pdev);
599		kfree(vdev->msix);
600	} else
601		pci_disable_msi(pdev);
602
603	vdev->irq_type = VFIO_PCI_NUM_IRQS;
604	vdev->num_ctx = 0;
605	kfree(vdev->ctx);
606}
607
608/*
609 * IOCTL support
610 */
611static int vfio_pci_set_intx_unmask(struct vfio_pci_device *vdev,
612				    unsigned index, unsigned start,
613				    unsigned count, uint32_t flags, void *data)
614{
615	if (!is_intx(vdev) || start != 0 || count != 1)
616		return -EINVAL;
617
618	if (flags & VFIO_IRQ_SET_DATA_NONE) {
619		vfio_pci_intx_unmask(vdev);
620	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
621		uint8_t unmask = *(uint8_t *)data;
622		if (unmask)
623			vfio_pci_intx_unmask(vdev);
624	} else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
625		int32_t fd = *(int32_t *)data;
626		if (fd >= 0)
627			return virqfd_enable(vdev, vfio_pci_intx_unmask_handler,
628					     vfio_send_intx_eventfd, NULL,
629					     &vdev->ctx[0].unmask, fd);
630
631		virqfd_disable(vdev, &vdev->ctx[0].unmask);
632	}
633
634	return 0;
635}
636
637static int vfio_pci_set_intx_mask(struct vfio_pci_device *vdev,
638				  unsigned index, unsigned start,
639				  unsigned count, uint32_t flags, void *data)
640{
641	if (!is_intx(vdev) || start != 0 || count != 1)
642		return -EINVAL;
643
644	if (flags & VFIO_IRQ_SET_DATA_NONE) {
645		vfio_pci_intx_mask(vdev);
646	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
647		uint8_t mask = *(uint8_t *)data;
648		if (mask)
649			vfio_pci_intx_mask(vdev);
650	} else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
651		return -ENOTTY; /* XXX implement me */
652	}
653
654	return 0;
655}
656
657static int vfio_pci_set_intx_trigger(struct vfio_pci_device *vdev,
658				     unsigned index, unsigned start,
659				     unsigned count, uint32_t flags, void *data)
660{
661	if (is_intx(vdev) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
662		vfio_intx_disable(vdev);
663		return 0;
664	}
665
666	if (!(is_intx(vdev) || is_irq_none(vdev)) || start != 0 || count != 1)
667		return -EINVAL;
668
669	if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
670		int32_t fd = *(int32_t *)data;
671		int ret;
672
673		if (is_intx(vdev))
674			return vfio_intx_set_signal(vdev, fd);
675
676		ret = vfio_intx_enable(vdev);
677		if (ret)
678			return ret;
679
680		ret = vfio_intx_set_signal(vdev, fd);
681		if (ret)
682			vfio_intx_disable(vdev);
683
684		return ret;
685	}
686
687	if (!is_intx(vdev))
688		return -EINVAL;
689
690	if (flags & VFIO_IRQ_SET_DATA_NONE) {
691		vfio_send_intx_eventfd(vdev, NULL);
692	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
693		uint8_t trigger = *(uint8_t *)data;
694		if (trigger)
695			vfio_send_intx_eventfd(vdev, NULL);
696	}
697	return 0;
698}
699
700static int vfio_pci_set_msi_trigger(struct vfio_pci_device *vdev,
701				    unsigned index, unsigned start,
702				    unsigned count, uint32_t flags, void *data)
703{
704	int i;
705	bool msix = (index == VFIO_PCI_MSIX_IRQ_INDEX) ? true : false;
706
707	if (irq_is(vdev, index) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
708		vfio_msi_disable(vdev, msix);
709		return 0;
710	}
711
712	if (!(irq_is(vdev, index) || is_irq_none(vdev)))
713		return -EINVAL;
714
715	if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
716		int32_t *fds = data;
717		int ret;
718
719		if (vdev->irq_type == index)
720			return vfio_msi_set_block(vdev, start, count,
721						  fds, msix);
722
723		ret = vfio_msi_enable(vdev, start + count, msix);
724		if (ret)
725			return ret;
726
727		ret = vfio_msi_set_block(vdev, start, count, fds, msix);
728		if (ret)
729			vfio_msi_disable(vdev, msix);
730
731		return ret;
732	}
733
734	if (!irq_is(vdev, index) || start + count > vdev->num_ctx)
735		return -EINVAL;
736
737	for (i = start; i < start + count; i++) {
738		if (!vdev->ctx[i].trigger)
739			continue;
740		if (flags & VFIO_IRQ_SET_DATA_NONE) {
741			eventfd_signal(vdev->ctx[i].trigger, 1);
742		} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
743			uint8_t *bools = data;
744			if (bools[i - start])
745				eventfd_signal(vdev->ctx[i].trigger, 1);
746		}
747	}
748	return 0;
749}
750
751static int vfio_pci_set_err_trigger(struct vfio_pci_device *vdev,
752				    unsigned index, unsigned start,
753				    unsigned count, uint32_t flags, void *data)
754{
755	int32_t fd = *(int32_t *)data;
756
757	if ((index != VFIO_PCI_ERR_IRQ_INDEX) ||
758	    !(flags & VFIO_IRQ_SET_DATA_TYPE_MASK))
759		return -EINVAL;
760
761	/* DATA_NONE/DATA_BOOL enables loopback testing */
762	if (flags & VFIO_IRQ_SET_DATA_NONE) {
763		if (vdev->err_trigger)
764			eventfd_signal(vdev->err_trigger, 1);
765		return 0;
766	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
767		uint8_t trigger = *(uint8_t *)data;
768		if (trigger && vdev->err_trigger)
769			eventfd_signal(vdev->err_trigger, 1);
770		return 0;
771	}
772
773	/* Handle SET_DATA_EVENTFD */
774	if (fd == -1) {
775		if (vdev->err_trigger)
776			eventfd_ctx_put(vdev->err_trigger);
777		vdev->err_trigger = NULL;
778		return 0;
779	} else if (fd >= 0) {
780		struct eventfd_ctx *efdctx;
781		efdctx = eventfd_ctx_fdget(fd);
782		if (IS_ERR(efdctx))
783			return PTR_ERR(efdctx);
784		if (vdev->err_trigger)
785			eventfd_ctx_put(vdev->err_trigger);
786		vdev->err_trigger = efdctx;
787		return 0;
788	} else
789		return -EINVAL;
790}
791int vfio_pci_set_irqs_ioctl(struct vfio_pci_device *vdev, uint32_t flags,
792			    unsigned index, unsigned start, unsigned count,
793			    void *data)
794{
795	int (*func)(struct vfio_pci_device *vdev, unsigned index,
796		    unsigned start, unsigned count, uint32_t flags,
797		    void *data) = NULL;
798
799	switch (index) {
800	case VFIO_PCI_INTX_IRQ_INDEX:
801		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
802		case VFIO_IRQ_SET_ACTION_MASK:
803			func = vfio_pci_set_intx_mask;
804			break;
805		case VFIO_IRQ_SET_ACTION_UNMASK:
806			func = vfio_pci_set_intx_unmask;
807			break;
808		case VFIO_IRQ_SET_ACTION_TRIGGER:
809			func = vfio_pci_set_intx_trigger;
810			break;
811		}
812		break;
813	case VFIO_PCI_MSI_IRQ_INDEX:
814	case VFIO_PCI_MSIX_IRQ_INDEX:
815		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
816		case VFIO_IRQ_SET_ACTION_MASK:
817		case VFIO_IRQ_SET_ACTION_UNMASK:
818			/* XXX Need masking support exported */
819			break;
820		case VFIO_IRQ_SET_ACTION_TRIGGER:
821			func = vfio_pci_set_msi_trigger;
822			break;
823		}
824		break;
825	case VFIO_PCI_ERR_IRQ_INDEX:
826		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
827		case VFIO_IRQ_SET_ACTION_TRIGGER:
828			if (pci_is_pcie(vdev->pdev))
829				func = vfio_pci_set_err_trigger;
830			break;
831		}
832	}
833
834	if (!func)
835		return -ENOTTY;
836
837	return func(vdev, index, start, count, flags, data);
838}
839