xref: /linux/drivers/vfio/pci/vfio_pci_intrs.c (revision abafbc551fddede3e0a08dee1dcde08fc0eb8476) 
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * VFIO PCI interrupt handling
4  *
5  * Copyright (C) 2012 Red Hat, Inc.  All rights reserved.
6  *     Author: Alex Williamson <alex.williamson@redhat.com>
7  *
8  * Derived from original vfio:
9  * Copyright 2010 Cisco Systems, Inc.  All rights reserved.
10  * Author: Tom Lyon, pugs@cisco.com
11  */
12 
13 #include <linux/device.h>
14 #include <linux/interrupt.h>
15 #include <linux/eventfd.h>
16 #include <linux/msi.h>
17 #include <linux/pci.h>
18 #include <linux/file.h>
19 #include <linux/vfio.h>
20 #include <linux/wait.h>
21 #include <linux/slab.h>
22 
23 #include "vfio_pci_private.h"
24 
25 /*
26  * INTx
27  */
28 static void vfio_send_intx_eventfd(void *opaque, void *unused)
29 {
30 	struct vfio_pci_device *vdev = opaque;
31 
32 	if (likely(is_intx(vdev) && !vdev->virq_disabled))
33 		eventfd_signal(vdev->ctx[0].trigger, 1);
34 }
35 
36 void vfio_pci_intx_mask(struct vfio_pci_device *vdev)
37 {
38 	struct pci_dev *pdev = vdev->pdev;
39 	unsigned long flags;
40 
41 	spin_lock_irqsave(&vdev->irqlock, flags);
42 
43 	/*
44 	 * Masking can come from interrupt, ioctl, or config space
45 	 * via INTx disable.  The latter means this can get called
46 	 * even when not using intx delivery.  In this case, just
47 	 * try to have the physical bit follow the virtual bit.
48 	 */
49 	if (unlikely(!is_intx(vdev))) {
50 		if (vdev->pci_2_3)
51 			pci_intx(pdev, 0);
52 	} else if (!vdev->ctx[0].masked) {
53 		/*
54 		 * Can't use check_and_mask here because we always want to
55 		 * mask, not just when something is pending.
56 		 */
57 		if (vdev->pci_2_3)
58 			pci_intx(pdev, 0);
59 		else
60 			disable_irq_nosync(pdev->irq);
61 
62 		vdev->ctx[0].masked = true;
63 	}
64 
65 	spin_unlock_irqrestore(&vdev->irqlock, flags);
66 }
67 
68 /*
69  * If this is triggered by an eventfd, we can't call eventfd_signal
70  * or else we'll deadlock on the eventfd wait queue.  Return >0 when
71  * a signal is necessary, which can then be handled via a work queue
72  * or directly depending on the caller.
73  */
74 static int vfio_pci_intx_unmask_handler(void *opaque, void *unused)
75 {
76 	struct vfio_pci_device *vdev = opaque;
77 	struct pci_dev *pdev = vdev->pdev;
78 	unsigned long flags;
79 	int ret = 0;
80 
81 	spin_lock_irqsave(&vdev->irqlock, flags);
82 
83 	/*
84 	 * Unmasking comes from ioctl or config, so again, have the
85 	 * physical bit follow the virtual even when not using INTx.
86 	 */
87 	if (unlikely(!is_intx(vdev))) {
88 		if (vdev->pci_2_3)
89 			pci_intx(pdev, 1);
90 	} else if (vdev->ctx[0].masked && !vdev->virq_disabled) {
91 		/*
92 		 * A pending interrupt here would immediately trigger,
93 		 * but we can avoid that overhead by just re-sending
94 		 * the interrupt to the user.
95 		 */
96 		if (vdev->pci_2_3) {
97 			if (!pci_check_and_unmask_intx(pdev))
98 				ret = 1;
99 		} else
100 			enable_irq(pdev->irq);
101 
102 		vdev->ctx[0].masked = (ret > 0);
103 	}
104 
105 	spin_unlock_irqrestore(&vdev->irqlock, flags);
106 
107 	return ret;
108 }
109 
110 void vfio_pci_intx_unmask(struct vfio_pci_device *vdev)
111 {
112 	if (vfio_pci_intx_unmask_handler(vdev, NULL) > 0)
113 		vfio_send_intx_eventfd(vdev, NULL);
114 }
115 
116 static irqreturn_t vfio_intx_handler(int irq, void *dev_id)
117 {
118 	struct vfio_pci_device *vdev = dev_id;
119 	unsigned long flags;
120 	int ret = IRQ_NONE;
121 
122 	spin_lock_irqsave(&vdev->irqlock, flags);
123 
124 	if (!vdev->pci_2_3) {
125 		disable_irq_nosync(vdev->pdev->irq);
126 		vdev->ctx[0].masked = true;
127 		ret = IRQ_HANDLED;
128 	} else if (!vdev->ctx[0].masked &&  /* may be shared */
129 		   pci_check_and_mask_intx(vdev->pdev)) {
130 		vdev->ctx[0].masked = true;
131 		ret = IRQ_HANDLED;
132 	}
133 
134 	spin_unlock_irqrestore(&vdev->irqlock, flags);
135 
136 	if (ret == IRQ_HANDLED)
137 		vfio_send_intx_eventfd(vdev, NULL);
138 
139 	return ret;
140 }
141 
142 static int vfio_intx_enable(struct vfio_pci_device *vdev)
143 {
144 	if (!is_irq_none(vdev))
145 		return -EINVAL;
146 
147 	if (!vdev->pdev->irq)
148 		return -ENODEV;
149 
150 	vdev->ctx = kzalloc(sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL);
151 	if (!vdev->ctx)
152 		return -ENOMEM;
153 
154 	vdev->num_ctx = 1;
155 
156 	/*
157 	 * If the virtual interrupt is masked, restore it.  Devices
158 	 * supporting DisINTx can be masked at the hardware level
159 	 * here, non-PCI-2.3 devices will have to wait until the
160 	 * interrupt is enabled.
161 	 */
162 	vdev->ctx[0].masked = vdev->virq_disabled;
163 	if (vdev->pci_2_3)
164 		pci_intx(vdev->pdev, !vdev->ctx[0].masked);
165 
166 	vdev->irq_type = VFIO_PCI_INTX_IRQ_INDEX;
167 
168 	return 0;
169 }
170 
171 static int vfio_intx_set_signal(struct vfio_pci_device *vdev, int fd)
172 {
173 	struct pci_dev *pdev = vdev->pdev;
174 	unsigned long irqflags = IRQF_SHARED;
175 	struct eventfd_ctx *trigger;
176 	unsigned long flags;
177 	int ret;
178 
179 	if (vdev->ctx[0].trigger) {
180 		free_irq(pdev->irq, vdev);
181 		kfree(vdev->ctx[0].name);
182 		eventfd_ctx_put(vdev->ctx[0].trigger);
183 		vdev->ctx[0].trigger = NULL;
184 	}
185 
186 	if (fd < 0) /* Disable only */
187 		return 0;
188 
189 	vdev->ctx[0].name = kasprintf(GFP_KERNEL, "vfio-intx(%s)",
190 				      pci_name(pdev));
191 	if (!vdev->ctx[0].name)
192 		return -ENOMEM;
193 
194 	trigger = eventfd_ctx_fdget(fd);
195 	if (IS_ERR(trigger)) {
196 		kfree(vdev->ctx[0].name);
197 		return PTR_ERR(trigger);
198 	}
199 
200 	vdev->ctx[0].trigger = trigger;
201 
202 	if (!vdev->pci_2_3)
203 		irqflags = 0;
204 
205 	ret = request_irq(pdev->irq, vfio_intx_handler,
206 			  irqflags, vdev->ctx[0].name, vdev);
207 	if (ret) {
208 		vdev->ctx[0].trigger = NULL;
209 		kfree(vdev->ctx[0].name);
210 		eventfd_ctx_put(trigger);
211 		return ret;
212 	}
213 
214 	/*
215 	 * INTx disable will stick across the new irq setup,
216 	 * disable_irq won't.
217 	 */
218 	spin_lock_irqsave(&vdev->irqlock, flags);
219 	if (!vdev->pci_2_3 && vdev->ctx[0].masked)
220 		disable_irq_nosync(pdev->irq);
221 	spin_unlock_irqrestore(&vdev->irqlock, flags);
222 
223 	return 0;
224 }
225 
226 static void vfio_intx_disable(struct vfio_pci_device *vdev)
227 {
228 	vfio_virqfd_disable(&vdev->ctx[0].unmask);
229 	vfio_virqfd_disable(&vdev->ctx[0].mask);
230 	vfio_intx_set_signal(vdev, -1);
231 	vdev->irq_type = VFIO_PCI_NUM_IRQS;
232 	vdev->num_ctx = 0;
233 	kfree(vdev->ctx);
234 }
235 
236 /*
237  * MSI/MSI-X
238  */
239 static irqreturn_t vfio_msihandler(int irq, void *arg)
240 {
241 	struct eventfd_ctx *trigger = arg;
242 
243 	eventfd_signal(trigger, 1);
244 	return IRQ_HANDLED;
245 }
246 
247 static int vfio_msi_enable(struct vfio_pci_device *vdev, int nvec, bool msix)
248 {
249 	struct pci_dev *pdev = vdev->pdev;
250 	unsigned int flag = msix ? PCI_IRQ_MSIX : PCI_IRQ_MSI;
251 	int ret;
252 	u16 cmd;
253 
254 	if (!is_irq_none(vdev))
255 		return -EINVAL;
256 
257 	vdev->ctx = kcalloc(nvec, sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL);
258 	if (!vdev->ctx)
259 		return -ENOMEM;
260 
261 	/* return the number of supported vectors if we can't get all: */
262 	cmd = vfio_pci_memory_lock_and_enable(vdev);
263 	ret = pci_alloc_irq_vectors(pdev, 1, nvec, flag);
264 	if (ret < nvec) {
265 		if (ret > 0)
266 			pci_free_irq_vectors(pdev);
267 		vfio_pci_memory_unlock_and_restore(vdev, cmd);
268 		kfree(vdev->ctx);
269 		return ret;
270 	}
271 	vfio_pci_memory_unlock_and_restore(vdev, cmd);
272 
273 	vdev->num_ctx = nvec;
274 	vdev->irq_type = msix ? VFIO_PCI_MSIX_IRQ_INDEX :
275 				VFIO_PCI_MSI_IRQ_INDEX;
276 
277 	if (!msix) {
278 		/*
279 		 * Compute the virtual hardware field for max msi vectors -
280 		 * it is the log base 2 of the number of vectors.
281 		 */
282 		vdev->msi_qmax = fls(nvec * 2 - 1) - 1;
283 	}
284 
285 	return 0;
286 }
287 
288 static int vfio_msi_set_vector_signal(struct vfio_pci_device *vdev,
289 				      int vector, int fd, bool msix)
290 {
291 	struct pci_dev *pdev = vdev->pdev;
292 	struct eventfd_ctx *trigger;
293 	int irq, ret;
294 	u16 cmd;
295 
296 	if (vector < 0 || vector >= vdev->num_ctx)
297 		return -EINVAL;
298 
299 	irq = pci_irq_vector(pdev, vector);
300 
301 	if (vdev->ctx[vector].trigger) {
302 		irq_bypass_unregister_producer(&vdev->ctx[vector].producer);
303 
304 		cmd = vfio_pci_memory_lock_and_enable(vdev);
305 		free_irq(irq, vdev->ctx[vector].trigger);
306 		vfio_pci_memory_unlock_and_restore(vdev, cmd);
307 
308 		kfree(vdev->ctx[vector].name);
309 		eventfd_ctx_put(vdev->ctx[vector].trigger);
310 		vdev->ctx[vector].trigger = NULL;
311 	}
312 
313 	if (fd < 0)
314 		return 0;
315 
316 	vdev->ctx[vector].name = kasprintf(GFP_KERNEL, "vfio-msi%s[%d](%s)",
317 					   msix ? "x" : "", vector,
318 					   pci_name(pdev));
319 	if (!vdev->ctx[vector].name)
320 		return -ENOMEM;
321 
322 	trigger = eventfd_ctx_fdget(fd);
323 	if (IS_ERR(trigger)) {
324 		kfree(vdev->ctx[vector].name);
325 		return PTR_ERR(trigger);
326 	}
327 
328 	/*
329 	 * The MSIx vector table resides in device memory which may be cleared
330 	 * via backdoor resets. We don't allow direct access to the vector
331 	 * table so even if a userspace driver attempts to save/restore around
332 	 * such a reset it would be unsuccessful. To avoid this, restore the
333 	 * cached value of the message prior to enabling.
334 	 */
335 	cmd = vfio_pci_memory_lock_and_enable(vdev);
336 	if (msix) {
337 		struct msi_msg msg;
338 
339 		get_cached_msi_msg(irq, &msg);
340 		pci_write_msi_msg(irq, &msg);
341 	}
342 
343 	ret = request_irq(irq, vfio_msihandler, 0,
344 			  vdev->ctx[vector].name, trigger);
345 	vfio_pci_memory_unlock_and_restore(vdev, cmd);
346 	if (ret) {
347 		kfree(vdev->ctx[vector].name);
348 		eventfd_ctx_put(trigger);
349 		return ret;
350 	}
351 
352 	vdev->ctx[vector].producer.token = trigger;
353 	vdev->ctx[vector].producer.irq = irq;
354 	ret = irq_bypass_register_producer(&vdev->ctx[vector].producer);
355 	if (unlikely(ret))
356 		dev_info(&pdev->dev,
357 		"irq bypass producer (token %p) registration fails: %d\n",
358 		vdev->ctx[vector].producer.token, ret);
359 
360 	vdev->ctx[vector].trigger = trigger;
361 
362 	return 0;
363 }
364 
365 static int vfio_msi_set_block(struct vfio_pci_device *vdev, unsigned start,
366 			      unsigned count, int32_t *fds, bool msix)
367 {
368 	int i, j, ret = 0;
369 
370 	if (start >= vdev->num_ctx || start + count > vdev->num_ctx)
371 		return -EINVAL;
372 
373 	for (i = 0, j = start; i < count && !ret; i++, j++) {
374 		int fd = fds ? fds[i] : -1;
375 		ret = vfio_msi_set_vector_signal(vdev, j, fd, msix);
376 	}
377 
378 	if (ret) {
379 		for (--j; j >= (int)start; j--)
380 			vfio_msi_set_vector_signal(vdev, j, -1, msix);
381 	}
382 
383 	return ret;
384 }
385 
386 static void vfio_msi_disable(struct vfio_pci_device *vdev, bool msix)
387 {
388 	struct pci_dev *pdev = vdev->pdev;
389 	int i;
390 	u16 cmd;
391 
392 	for (i = 0; i < vdev->num_ctx; i++) {
393 		vfio_virqfd_disable(&vdev->ctx[i].unmask);
394 		vfio_virqfd_disable(&vdev->ctx[i].mask);
395 	}
396 
397 	vfio_msi_set_block(vdev, 0, vdev->num_ctx, NULL, msix);
398 
399 	cmd = vfio_pci_memory_lock_and_enable(vdev);
400 	pci_free_irq_vectors(pdev);
401 	vfio_pci_memory_unlock_and_restore(vdev, cmd);
402 
403 	/*
404 	 * Both disable paths above use pci_intx_for_msi() to clear DisINTx
405 	 * via their shutdown paths.  Restore for NoINTx devices.
406 	 */
407 	if (vdev->nointx)
408 		pci_intx(pdev, 0);
409 
410 	vdev->irq_type = VFIO_PCI_NUM_IRQS;
411 	vdev->num_ctx = 0;
412 	kfree(vdev->ctx);
413 }
414 
415 /*
416  * IOCTL support
417  */
418 static int vfio_pci_set_intx_unmask(struct vfio_pci_device *vdev,
419 				    unsigned index, unsigned start,
420 				    unsigned count, uint32_t flags, void *data)
421 {
422 	if (!is_intx(vdev) || start != 0 || count != 1)
423 		return -EINVAL;
424 
425 	if (flags & VFIO_IRQ_SET_DATA_NONE) {
426 		vfio_pci_intx_unmask(vdev);
427 	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
428 		uint8_t unmask = *(uint8_t *)data;
429 		if (unmask)
430 			vfio_pci_intx_unmask(vdev);
431 	} else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
432 		int32_t fd = *(int32_t *)data;
433 		if (fd >= 0)
434 			return vfio_virqfd_enable((void *) vdev,
435 						  vfio_pci_intx_unmask_handler,
436 						  vfio_send_intx_eventfd, NULL,
437 						  &vdev->ctx[0].unmask, fd);
438 
439 		vfio_virqfd_disable(&vdev->ctx[0].unmask);
440 	}
441 
442 	return 0;
443 }
444 
445 static int vfio_pci_set_intx_mask(struct vfio_pci_device *vdev,
446 				  unsigned index, unsigned start,
447 				  unsigned count, uint32_t flags, void *data)
448 {
449 	if (!is_intx(vdev) || start != 0 || count != 1)
450 		return -EINVAL;
451 
452 	if (flags & VFIO_IRQ_SET_DATA_NONE) {
453 		vfio_pci_intx_mask(vdev);
454 	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
455 		uint8_t mask = *(uint8_t *)data;
456 		if (mask)
457 			vfio_pci_intx_mask(vdev);
458 	} else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
459 		return -ENOTTY; /* XXX implement me */
460 	}
461 
462 	return 0;
463 }
464 
465 static int vfio_pci_set_intx_trigger(struct vfio_pci_device *vdev,
466 				     unsigned index, unsigned start,
467 				     unsigned count, uint32_t flags, void *data)
468 {
469 	if (is_intx(vdev) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
470 		vfio_intx_disable(vdev);
471 		return 0;
472 	}
473 
474 	if (!(is_intx(vdev) || is_irq_none(vdev)) || start != 0 || count != 1)
475 		return -EINVAL;
476 
477 	if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
478 		int32_t fd = *(int32_t *)data;
479 		int ret;
480 
481 		if (is_intx(vdev))
482 			return vfio_intx_set_signal(vdev, fd);
483 
484 		ret = vfio_intx_enable(vdev);
485 		if (ret)
486 			return ret;
487 
488 		ret = vfio_intx_set_signal(vdev, fd);
489 		if (ret)
490 			vfio_intx_disable(vdev);
491 
492 		return ret;
493 	}
494 
495 	if (!is_intx(vdev))
496 		return -EINVAL;
497 
498 	if (flags & VFIO_IRQ_SET_DATA_NONE) {
499 		vfio_send_intx_eventfd(vdev, NULL);
500 	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
501 		uint8_t trigger = *(uint8_t *)data;
502 		if (trigger)
503 			vfio_send_intx_eventfd(vdev, NULL);
504 	}
505 	return 0;
506 }
507 
508 static int vfio_pci_set_msi_trigger(struct vfio_pci_device *vdev,
509 				    unsigned index, unsigned start,
510 				    unsigned count, uint32_t flags, void *data)
511 {
512 	int i;
513 	bool msix = (index == VFIO_PCI_MSIX_IRQ_INDEX) ? true : false;
514 
515 	if (irq_is(vdev, index) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
516 		vfio_msi_disable(vdev, msix);
517 		return 0;
518 	}
519 
520 	if (!(irq_is(vdev, index) || is_irq_none(vdev)))
521 		return -EINVAL;
522 
523 	if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
524 		int32_t *fds = data;
525 		int ret;
526 
527 		if (vdev->irq_type == index)
528 			return vfio_msi_set_block(vdev, start, count,
529 						  fds, msix);
530 
531 		ret = vfio_msi_enable(vdev, start + count, msix);
532 		if (ret)
533 			return ret;
534 
535 		ret = vfio_msi_set_block(vdev, start, count, fds, msix);
536 		if (ret)
537 			vfio_msi_disable(vdev, msix);
538 
539 		return ret;
540 	}
541 
542 	if (!irq_is(vdev, index) || start + count > vdev->num_ctx)
543 		return -EINVAL;
544 
545 	for (i = start; i < start + count; i++) {
546 		if (!vdev->ctx[i].trigger)
547 			continue;
548 		if (flags & VFIO_IRQ_SET_DATA_NONE) {
549 			eventfd_signal(vdev->ctx[i].trigger, 1);
550 		} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
551 			uint8_t *bools = data;
552 			if (bools[i - start])
553 				eventfd_signal(vdev->ctx[i].trigger, 1);
554 		}
555 	}
556 	return 0;
557 }
558 
559 static int vfio_pci_set_ctx_trigger_single(struct eventfd_ctx **ctx,
560 					   unsigned int count, uint32_t flags,
561 					   void *data)
562 {
563 	/* DATA_NONE/DATA_BOOL enables loopback testing */
564 	if (flags & VFIO_IRQ_SET_DATA_NONE) {
565 		if (*ctx) {
566 			if (count) {
567 				eventfd_signal(*ctx, 1);
568 			} else {
569 				eventfd_ctx_put(*ctx);
570 				*ctx = NULL;
571 			}
572 			return 0;
573 		}
574 	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
575 		uint8_t trigger;
576 
577 		if (!count)
578 			return -EINVAL;
579 
580 		trigger = *(uint8_t *)data;
581 		if (trigger && *ctx)
582 			eventfd_signal(*ctx, 1);
583 
584 		return 0;
585 	} else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
586 		int32_t fd;
587 
588 		if (!count)
589 			return -EINVAL;
590 
591 		fd = *(int32_t *)data;
592 		if (fd == -1) {
593 			if (*ctx)
594 				eventfd_ctx_put(*ctx);
595 			*ctx = NULL;
596 		} else if (fd >= 0) {
597 			struct eventfd_ctx *efdctx;
598 
599 			efdctx = eventfd_ctx_fdget(fd);
600 			if (IS_ERR(efdctx))
601 				return PTR_ERR(efdctx);
602 
603 			if (*ctx)
604 				eventfd_ctx_put(*ctx);
605 
606 			*ctx = efdctx;
607 		}
608 		return 0;
609 	}
610 
611 	return -EINVAL;
612 }
613 
614 static int vfio_pci_set_err_trigger(struct vfio_pci_device *vdev,
615 				    unsigned index, unsigned start,
616 				    unsigned count, uint32_t flags, void *data)
617 {
618 	if (index != VFIO_PCI_ERR_IRQ_INDEX || start != 0 || count > 1)
619 		return -EINVAL;
620 
621 	return vfio_pci_set_ctx_trigger_single(&vdev->err_trigger,
622 					       count, flags, data);
623 }
624 
625 static int vfio_pci_set_req_trigger(struct vfio_pci_device *vdev,
626 				    unsigned index, unsigned start,
627 				    unsigned count, uint32_t flags, void *data)
628 {
629 	if (index != VFIO_PCI_REQ_IRQ_INDEX || start != 0 || count > 1)
630 		return -EINVAL;
631 
632 	return vfio_pci_set_ctx_trigger_single(&vdev->req_trigger,
633 					       count, flags, data);
634 }
635 
636 int vfio_pci_set_irqs_ioctl(struct vfio_pci_device *vdev, uint32_t flags,
637 			    unsigned index, unsigned start, unsigned count,
638 			    void *data)
639 {
640 	int (*func)(struct vfio_pci_device *vdev, unsigned index,
641 		    unsigned start, unsigned count, uint32_t flags,
642 		    void *data) = NULL;
643 
644 	switch (index) {
645 	case VFIO_PCI_INTX_IRQ_INDEX:
646 		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
647 		case VFIO_IRQ_SET_ACTION_MASK:
648 			func = vfio_pci_set_intx_mask;
649 			break;
650 		case VFIO_IRQ_SET_ACTION_UNMASK:
651 			func = vfio_pci_set_intx_unmask;
652 			break;
653 		case VFIO_IRQ_SET_ACTION_TRIGGER:
654 			func = vfio_pci_set_intx_trigger;
655 			break;
656 		}
657 		break;
658 	case VFIO_PCI_MSI_IRQ_INDEX:
659 	case VFIO_PCI_MSIX_IRQ_INDEX:
660 		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
661 		case VFIO_IRQ_SET_ACTION_MASK:
662 		case VFIO_IRQ_SET_ACTION_UNMASK:
663 			/* XXX Need masking support exported */
664 			break;
665 		case VFIO_IRQ_SET_ACTION_TRIGGER:
666 			func = vfio_pci_set_msi_trigger;
667 			break;
668 		}
669 		break;
670 	case VFIO_PCI_ERR_IRQ_INDEX:
671 		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
672 		case VFIO_IRQ_SET_ACTION_TRIGGER:
673 			if (pci_is_pcie(vdev->pdev))
674 				func = vfio_pci_set_err_trigger;
675 			break;
676 		}
677 		break;
678 	case VFIO_PCI_REQ_IRQ_INDEX:
679 		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
680 		case VFIO_IRQ_SET_ACTION_TRIGGER:
681 			func = vfio_pci_set_req_trigger;
682 			break;
683 		}
684 		break;
685 	}
686 
687 	if (!func)
688 		return -ENOTTY;
689 
690 	return func(vdev, index, start, count, flags, data);
691 }
692