xref: /linux/drivers/vfio/pci/vfio_pci_intrs.c (revision 6578ed85c7d63693669bfede01e0237d0e24211a)
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_priv.h"
24 
25 struct vfio_pci_irq_ctx {
26 	struct eventfd_ctx	*trigger;
27 	struct virqfd		*unmask;
28 	struct virqfd		*mask;
29 	char			*name;
30 	bool			masked;
31 	struct irq_bypass_producer	producer;
32 };
33 
34 static bool irq_is(struct vfio_pci_core_device *vdev, int type)
35 {
36 	return vdev->irq_type == type;
37 }
38 
39 static bool is_intx(struct vfio_pci_core_device *vdev)
40 {
41 	return vdev->irq_type == VFIO_PCI_INTX_IRQ_INDEX;
42 }
43 
44 static bool is_irq_none(struct vfio_pci_core_device *vdev)
45 {
46 	return !(vdev->irq_type == VFIO_PCI_INTX_IRQ_INDEX ||
47 		 vdev->irq_type == VFIO_PCI_MSI_IRQ_INDEX ||
48 		 vdev->irq_type == VFIO_PCI_MSIX_IRQ_INDEX);
49 }
50 
51 /*
52  * INTx
53  */
54 static void vfio_send_intx_eventfd(void *opaque, void *unused)
55 {
56 	struct vfio_pci_core_device *vdev = opaque;
57 
58 	if (likely(is_intx(vdev) && !vdev->virq_disabled))
59 		eventfd_signal(vdev->ctx[0].trigger, 1);
60 }
61 
62 /* Returns true if the INTx vfio_pci_irq_ctx.masked value is changed. */
63 bool vfio_pci_intx_mask(struct vfio_pci_core_device *vdev)
64 {
65 	struct pci_dev *pdev = vdev->pdev;
66 	unsigned long flags;
67 	bool masked_changed = false;
68 
69 	spin_lock_irqsave(&vdev->irqlock, flags);
70 
71 	/*
72 	 * Masking can come from interrupt, ioctl, or config space
73 	 * via INTx disable.  The latter means this can get called
74 	 * even when not using intx delivery.  In this case, just
75 	 * try to have the physical bit follow the virtual bit.
76 	 */
77 	if (unlikely(!is_intx(vdev))) {
78 		if (vdev->pci_2_3)
79 			pci_intx(pdev, 0);
80 	} else if (!vdev->ctx[0].masked) {
81 		/*
82 		 * Can't use check_and_mask here because we always want to
83 		 * mask, not just when something is pending.
84 		 */
85 		if (vdev->pci_2_3)
86 			pci_intx(pdev, 0);
87 		else
88 			disable_irq_nosync(pdev->irq);
89 
90 		vdev->ctx[0].masked = true;
91 		masked_changed = true;
92 	}
93 
94 	spin_unlock_irqrestore(&vdev->irqlock, flags);
95 	return masked_changed;
96 }
97 
98 /*
99  * If this is triggered by an eventfd, we can't call eventfd_signal
100  * or else we'll deadlock on the eventfd wait queue.  Return >0 when
101  * a signal is necessary, which can then be handled via a work queue
102  * or directly depending on the caller.
103  */
104 static int vfio_pci_intx_unmask_handler(void *opaque, void *unused)
105 {
106 	struct vfio_pci_core_device *vdev = opaque;
107 	struct pci_dev *pdev = vdev->pdev;
108 	unsigned long flags;
109 	int ret = 0;
110 
111 	spin_lock_irqsave(&vdev->irqlock, flags);
112 
113 	/*
114 	 * Unmasking comes from ioctl or config, so again, have the
115 	 * physical bit follow the virtual even when not using INTx.
116 	 */
117 	if (unlikely(!is_intx(vdev))) {
118 		if (vdev->pci_2_3)
119 			pci_intx(pdev, 1);
120 	} else if (vdev->ctx[0].masked && !vdev->virq_disabled) {
121 		/*
122 		 * A pending interrupt here would immediately trigger,
123 		 * but we can avoid that overhead by just re-sending
124 		 * the interrupt to the user.
125 		 */
126 		if (vdev->pci_2_3) {
127 			if (!pci_check_and_unmask_intx(pdev))
128 				ret = 1;
129 		} else
130 			enable_irq(pdev->irq);
131 
132 		vdev->ctx[0].masked = (ret > 0);
133 	}
134 
135 	spin_unlock_irqrestore(&vdev->irqlock, flags);
136 
137 	return ret;
138 }
139 
140 void vfio_pci_intx_unmask(struct vfio_pci_core_device *vdev)
141 {
142 	if (vfio_pci_intx_unmask_handler(vdev, NULL) > 0)
143 		vfio_send_intx_eventfd(vdev, NULL);
144 }
145 
146 static irqreturn_t vfio_intx_handler(int irq, void *dev_id)
147 {
148 	struct vfio_pci_core_device *vdev = dev_id;
149 	unsigned long flags;
150 	int ret = IRQ_NONE;
151 
152 	spin_lock_irqsave(&vdev->irqlock, flags);
153 
154 	if (!vdev->pci_2_3) {
155 		disable_irq_nosync(vdev->pdev->irq);
156 		vdev->ctx[0].masked = true;
157 		ret = IRQ_HANDLED;
158 	} else if (!vdev->ctx[0].masked &&  /* may be shared */
159 		   pci_check_and_mask_intx(vdev->pdev)) {
160 		vdev->ctx[0].masked = true;
161 		ret = IRQ_HANDLED;
162 	}
163 
164 	spin_unlock_irqrestore(&vdev->irqlock, flags);
165 
166 	if (ret == IRQ_HANDLED)
167 		vfio_send_intx_eventfd(vdev, NULL);
168 
169 	return ret;
170 }
171 
172 static int vfio_intx_enable(struct vfio_pci_core_device *vdev)
173 {
174 	if (!is_irq_none(vdev))
175 		return -EINVAL;
176 
177 	if (!vdev->pdev->irq)
178 		return -ENODEV;
179 
180 	vdev->ctx = kzalloc(sizeof(struct vfio_pci_irq_ctx), GFP_KERNEL_ACCOUNT);
181 	if (!vdev->ctx)
182 		return -ENOMEM;
183 
184 	vdev->num_ctx = 1;
185 
186 	/*
187 	 * If the virtual interrupt is masked, restore it.  Devices
188 	 * supporting DisINTx can be masked at the hardware level
189 	 * here, non-PCI-2.3 devices will have to wait until the
190 	 * interrupt is enabled.
191 	 */
192 	vdev->ctx[0].masked = vdev->virq_disabled;
193 	if (vdev->pci_2_3)
194 		pci_intx(vdev->pdev, !vdev->ctx[0].masked);
195 
196 	vdev->irq_type = VFIO_PCI_INTX_IRQ_INDEX;
197 
198 	return 0;
199 }
200 
201 static int vfio_intx_set_signal(struct vfio_pci_core_device *vdev, int fd)
202 {
203 	struct pci_dev *pdev = vdev->pdev;
204 	unsigned long irqflags = IRQF_SHARED;
205 	struct eventfd_ctx *trigger;
206 	unsigned long flags;
207 	int ret;
208 
209 	if (vdev->ctx[0].trigger) {
210 		free_irq(pdev->irq, vdev);
211 		kfree(vdev->ctx[0].name);
212 		eventfd_ctx_put(vdev->ctx[0].trigger);
213 		vdev->ctx[0].trigger = NULL;
214 	}
215 
216 	if (fd < 0) /* Disable only */
217 		return 0;
218 
219 	vdev->ctx[0].name = kasprintf(GFP_KERNEL_ACCOUNT, "vfio-intx(%s)",
220 				      pci_name(pdev));
221 	if (!vdev->ctx[0].name)
222 		return -ENOMEM;
223 
224 	trigger = eventfd_ctx_fdget(fd);
225 	if (IS_ERR(trigger)) {
226 		kfree(vdev->ctx[0].name);
227 		return PTR_ERR(trigger);
228 	}
229 
230 	vdev->ctx[0].trigger = trigger;
231 
232 	if (!vdev->pci_2_3)
233 		irqflags = 0;
234 
235 	ret = request_irq(pdev->irq, vfio_intx_handler,
236 			  irqflags, vdev->ctx[0].name, vdev);
237 	if (ret) {
238 		vdev->ctx[0].trigger = NULL;
239 		kfree(vdev->ctx[0].name);
240 		eventfd_ctx_put(trigger);
241 		return ret;
242 	}
243 
244 	/*
245 	 * INTx disable will stick across the new irq setup,
246 	 * disable_irq won't.
247 	 */
248 	spin_lock_irqsave(&vdev->irqlock, flags);
249 	if (!vdev->pci_2_3 && vdev->ctx[0].masked)
250 		disable_irq_nosync(pdev->irq);
251 	spin_unlock_irqrestore(&vdev->irqlock, flags);
252 
253 	return 0;
254 }
255 
256 static void vfio_intx_disable(struct vfio_pci_core_device *vdev)
257 {
258 	vfio_virqfd_disable(&vdev->ctx[0].unmask);
259 	vfio_virqfd_disable(&vdev->ctx[0].mask);
260 	vfio_intx_set_signal(vdev, -1);
261 	vdev->irq_type = VFIO_PCI_NUM_IRQS;
262 	vdev->num_ctx = 0;
263 	kfree(vdev->ctx);
264 }
265 
266 /*
267  * MSI/MSI-X
268  */
269 static irqreturn_t vfio_msihandler(int irq, void *arg)
270 {
271 	struct eventfd_ctx *trigger = arg;
272 
273 	eventfd_signal(trigger, 1);
274 	return IRQ_HANDLED;
275 }
276 
277 static int vfio_msi_enable(struct vfio_pci_core_device *vdev, int nvec, bool msix)
278 {
279 	struct pci_dev *pdev = vdev->pdev;
280 	unsigned int flag = msix ? PCI_IRQ_MSIX : PCI_IRQ_MSI;
281 	int ret;
282 	u16 cmd;
283 
284 	if (!is_irq_none(vdev))
285 		return -EINVAL;
286 
287 	vdev->ctx = kcalloc(nvec, sizeof(struct vfio_pci_irq_ctx),
288 			    GFP_KERNEL_ACCOUNT);
289 	if (!vdev->ctx)
290 		return -ENOMEM;
291 
292 	/* return the number of supported vectors if we can't get all: */
293 	cmd = vfio_pci_memory_lock_and_enable(vdev);
294 	ret = pci_alloc_irq_vectors(pdev, 1, nvec, flag);
295 	if (ret < nvec) {
296 		if (ret > 0)
297 			pci_free_irq_vectors(pdev);
298 		vfio_pci_memory_unlock_and_restore(vdev, cmd);
299 		kfree(vdev->ctx);
300 		return ret;
301 	}
302 	vfio_pci_memory_unlock_and_restore(vdev, cmd);
303 
304 	vdev->num_ctx = nvec;
305 	vdev->irq_type = msix ? VFIO_PCI_MSIX_IRQ_INDEX :
306 				VFIO_PCI_MSI_IRQ_INDEX;
307 
308 	if (!msix) {
309 		/*
310 		 * Compute the virtual hardware field for max msi vectors -
311 		 * it is the log base 2 of the number of vectors.
312 		 */
313 		vdev->msi_qmax = fls(nvec * 2 - 1) - 1;
314 	}
315 
316 	return 0;
317 }
318 
319 static int vfio_msi_set_vector_signal(struct vfio_pci_core_device *vdev,
320 				      unsigned int vector, int fd, bool msix)
321 {
322 	struct pci_dev *pdev = vdev->pdev;
323 	struct eventfd_ctx *trigger;
324 	int irq, ret;
325 	u16 cmd;
326 
327 	if (vector >= vdev->num_ctx)
328 		return -EINVAL;
329 
330 	irq = pci_irq_vector(pdev, vector);
331 
332 	if (vdev->ctx[vector].trigger) {
333 		irq_bypass_unregister_producer(&vdev->ctx[vector].producer);
334 
335 		cmd = vfio_pci_memory_lock_and_enable(vdev);
336 		free_irq(irq, vdev->ctx[vector].trigger);
337 		vfio_pci_memory_unlock_and_restore(vdev, cmd);
338 
339 		kfree(vdev->ctx[vector].name);
340 		eventfd_ctx_put(vdev->ctx[vector].trigger);
341 		vdev->ctx[vector].trigger = NULL;
342 	}
343 
344 	if (fd < 0)
345 		return 0;
346 
347 	vdev->ctx[vector].name = kasprintf(GFP_KERNEL_ACCOUNT,
348 					   "vfio-msi%s[%d](%s)",
349 					   msix ? "x" : "", vector,
350 					   pci_name(pdev));
351 	if (!vdev->ctx[vector].name)
352 		return -ENOMEM;
353 
354 	trigger = eventfd_ctx_fdget(fd);
355 	if (IS_ERR(trigger)) {
356 		kfree(vdev->ctx[vector].name);
357 		return PTR_ERR(trigger);
358 	}
359 
360 	/*
361 	 * The MSIx vector table resides in device memory which may be cleared
362 	 * via backdoor resets. We don't allow direct access to the vector
363 	 * table so even if a userspace driver attempts to save/restore around
364 	 * such a reset it would be unsuccessful. To avoid this, restore the
365 	 * cached value of the message prior to enabling.
366 	 */
367 	cmd = vfio_pci_memory_lock_and_enable(vdev);
368 	if (msix) {
369 		struct msi_msg msg;
370 
371 		get_cached_msi_msg(irq, &msg);
372 		pci_write_msi_msg(irq, &msg);
373 	}
374 
375 	ret = request_irq(irq, vfio_msihandler, 0,
376 			  vdev->ctx[vector].name, trigger);
377 	vfio_pci_memory_unlock_and_restore(vdev, cmd);
378 	if (ret) {
379 		kfree(vdev->ctx[vector].name);
380 		eventfd_ctx_put(trigger);
381 		return ret;
382 	}
383 
384 	vdev->ctx[vector].producer.token = trigger;
385 	vdev->ctx[vector].producer.irq = irq;
386 	ret = irq_bypass_register_producer(&vdev->ctx[vector].producer);
387 	if (unlikely(ret)) {
388 		dev_info(&pdev->dev,
389 		"irq bypass producer (token %p) registration fails: %d\n",
390 		vdev->ctx[vector].producer.token, ret);
391 
392 		vdev->ctx[vector].producer.token = NULL;
393 	}
394 	vdev->ctx[vector].trigger = trigger;
395 
396 	return 0;
397 }
398 
399 static int vfio_msi_set_block(struct vfio_pci_core_device *vdev, unsigned start,
400 			      unsigned count, int32_t *fds, bool msix)
401 {
402 	unsigned int i, j;
403 	int ret = 0;
404 
405 	if (start >= vdev->num_ctx || start + count > vdev->num_ctx)
406 		return -EINVAL;
407 
408 	for (i = 0, j = start; i < count && !ret; i++, j++) {
409 		int fd = fds ? fds[i] : -1;
410 		ret = vfio_msi_set_vector_signal(vdev, j, fd, msix);
411 	}
412 
413 	if (ret) {
414 		for (i = start; i < j; i++)
415 			vfio_msi_set_vector_signal(vdev, i, -1, msix);
416 	}
417 
418 	return ret;
419 }
420 
421 static void vfio_msi_disable(struct vfio_pci_core_device *vdev, bool msix)
422 {
423 	struct pci_dev *pdev = vdev->pdev;
424 	unsigned int i;
425 	u16 cmd;
426 
427 	for (i = 0; i < vdev->num_ctx; i++) {
428 		vfio_virqfd_disable(&vdev->ctx[i].unmask);
429 		vfio_virqfd_disable(&vdev->ctx[i].mask);
430 		vfio_msi_set_vector_signal(vdev, i, -1, msix);
431 	}
432 
433 	cmd = vfio_pci_memory_lock_and_enable(vdev);
434 	pci_free_irq_vectors(pdev);
435 	vfio_pci_memory_unlock_and_restore(vdev, cmd);
436 
437 	/*
438 	 * Both disable paths above use pci_intx_for_msi() to clear DisINTx
439 	 * via their shutdown paths.  Restore for NoINTx devices.
440 	 */
441 	if (vdev->nointx)
442 		pci_intx(pdev, 0);
443 
444 	vdev->irq_type = VFIO_PCI_NUM_IRQS;
445 	vdev->num_ctx = 0;
446 	kfree(vdev->ctx);
447 }
448 
449 /*
450  * IOCTL support
451  */
452 static int vfio_pci_set_intx_unmask(struct vfio_pci_core_device *vdev,
453 				    unsigned index, unsigned start,
454 				    unsigned count, uint32_t flags, void *data)
455 {
456 	if (!is_intx(vdev) || start != 0 || count != 1)
457 		return -EINVAL;
458 
459 	if (flags & VFIO_IRQ_SET_DATA_NONE) {
460 		vfio_pci_intx_unmask(vdev);
461 	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
462 		uint8_t unmask = *(uint8_t *)data;
463 		if (unmask)
464 			vfio_pci_intx_unmask(vdev);
465 	} else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
466 		int32_t fd = *(int32_t *)data;
467 		if (fd >= 0)
468 			return vfio_virqfd_enable((void *) vdev,
469 						  vfio_pci_intx_unmask_handler,
470 						  vfio_send_intx_eventfd, NULL,
471 						  &vdev->ctx[0].unmask, fd);
472 
473 		vfio_virqfd_disable(&vdev->ctx[0].unmask);
474 	}
475 
476 	return 0;
477 }
478 
479 static int vfio_pci_set_intx_mask(struct vfio_pci_core_device *vdev,
480 				  unsigned index, unsigned start,
481 				  unsigned count, uint32_t flags, void *data)
482 {
483 	if (!is_intx(vdev) || start != 0 || count != 1)
484 		return -EINVAL;
485 
486 	if (flags & VFIO_IRQ_SET_DATA_NONE) {
487 		vfio_pci_intx_mask(vdev);
488 	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
489 		uint8_t mask = *(uint8_t *)data;
490 		if (mask)
491 			vfio_pci_intx_mask(vdev);
492 	} else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
493 		return -ENOTTY; /* XXX implement me */
494 	}
495 
496 	return 0;
497 }
498 
499 static int vfio_pci_set_intx_trigger(struct vfio_pci_core_device *vdev,
500 				     unsigned index, unsigned start,
501 				     unsigned count, uint32_t flags, void *data)
502 {
503 	if (is_intx(vdev) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
504 		vfio_intx_disable(vdev);
505 		return 0;
506 	}
507 
508 	if (!(is_intx(vdev) || is_irq_none(vdev)) || start != 0 || count != 1)
509 		return -EINVAL;
510 
511 	if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
512 		int32_t fd = *(int32_t *)data;
513 		int ret;
514 
515 		if (is_intx(vdev))
516 			return vfio_intx_set_signal(vdev, fd);
517 
518 		ret = vfio_intx_enable(vdev);
519 		if (ret)
520 			return ret;
521 
522 		ret = vfio_intx_set_signal(vdev, fd);
523 		if (ret)
524 			vfio_intx_disable(vdev);
525 
526 		return ret;
527 	}
528 
529 	if (!is_intx(vdev))
530 		return -EINVAL;
531 
532 	if (flags & VFIO_IRQ_SET_DATA_NONE) {
533 		vfio_send_intx_eventfd(vdev, NULL);
534 	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
535 		uint8_t trigger = *(uint8_t *)data;
536 		if (trigger)
537 			vfio_send_intx_eventfd(vdev, NULL);
538 	}
539 	return 0;
540 }
541 
542 static int vfio_pci_set_msi_trigger(struct vfio_pci_core_device *vdev,
543 				    unsigned index, unsigned start,
544 				    unsigned count, uint32_t flags, void *data)
545 {
546 	unsigned int i;
547 	bool msix = (index == VFIO_PCI_MSIX_IRQ_INDEX) ? true : false;
548 
549 	if (irq_is(vdev, index) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
550 		vfio_msi_disable(vdev, msix);
551 		return 0;
552 	}
553 
554 	if (!(irq_is(vdev, index) || is_irq_none(vdev)))
555 		return -EINVAL;
556 
557 	if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
558 		int32_t *fds = data;
559 		int ret;
560 
561 		if (vdev->irq_type == index)
562 			return vfio_msi_set_block(vdev, start, count,
563 						  fds, msix);
564 
565 		ret = vfio_msi_enable(vdev, start + count, msix);
566 		if (ret)
567 			return ret;
568 
569 		ret = vfio_msi_set_block(vdev, start, count, fds, msix);
570 		if (ret)
571 			vfio_msi_disable(vdev, msix);
572 
573 		return ret;
574 	}
575 
576 	if (!irq_is(vdev, index) || start + count > vdev->num_ctx)
577 		return -EINVAL;
578 
579 	for (i = start; i < start + count; i++) {
580 		if (!vdev->ctx[i].trigger)
581 			continue;
582 		if (flags & VFIO_IRQ_SET_DATA_NONE) {
583 			eventfd_signal(vdev->ctx[i].trigger, 1);
584 		} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
585 			uint8_t *bools = data;
586 			if (bools[i - start])
587 				eventfd_signal(vdev->ctx[i].trigger, 1);
588 		}
589 	}
590 	return 0;
591 }
592 
593 static int vfio_pci_set_ctx_trigger_single(struct eventfd_ctx **ctx,
594 					   unsigned int count, uint32_t flags,
595 					   void *data)
596 {
597 	/* DATA_NONE/DATA_BOOL enables loopback testing */
598 	if (flags & VFIO_IRQ_SET_DATA_NONE) {
599 		if (*ctx) {
600 			if (count) {
601 				eventfd_signal(*ctx, 1);
602 			} else {
603 				eventfd_ctx_put(*ctx);
604 				*ctx = NULL;
605 			}
606 			return 0;
607 		}
608 	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
609 		uint8_t trigger;
610 
611 		if (!count)
612 			return -EINVAL;
613 
614 		trigger = *(uint8_t *)data;
615 		if (trigger && *ctx)
616 			eventfd_signal(*ctx, 1);
617 
618 		return 0;
619 	} else if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
620 		int32_t fd;
621 
622 		if (!count)
623 			return -EINVAL;
624 
625 		fd = *(int32_t *)data;
626 		if (fd == -1) {
627 			if (*ctx)
628 				eventfd_ctx_put(*ctx);
629 			*ctx = NULL;
630 		} else if (fd >= 0) {
631 			struct eventfd_ctx *efdctx;
632 
633 			efdctx = eventfd_ctx_fdget(fd);
634 			if (IS_ERR(efdctx))
635 				return PTR_ERR(efdctx);
636 
637 			if (*ctx)
638 				eventfd_ctx_put(*ctx);
639 
640 			*ctx = efdctx;
641 		}
642 		return 0;
643 	}
644 
645 	return -EINVAL;
646 }
647 
648 static int vfio_pci_set_err_trigger(struct vfio_pci_core_device *vdev,
649 				    unsigned index, unsigned start,
650 				    unsigned count, uint32_t flags, void *data)
651 {
652 	if (index != VFIO_PCI_ERR_IRQ_INDEX || start != 0 || count > 1)
653 		return -EINVAL;
654 
655 	return vfio_pci_set_ctx_trigger_single(&vdev->err_trigger,
656 					       count, flags, data);
657 }
658 
659 static int vfio_pci_set_req_trigger(struct vfio_pci_core_device *vdev,
660 				    unsigned index, unsigned start,
661 				    unsigned count, uint32_t flags, void *data)
662 {
663 	if (index != VFIO_PCI_REQ_IRQ_INDEX || start != 0 || count > 1)
664 		return -EINVAL;
665 
666 	return vfio_pci_set_ctx_trigger_single(&vdev->req_trigger,
667 					       count, flags, data);
668 }
669 
670 int vfio_pci_set_irqs_ioctl(struct vfio_pci_core_device *vdev, uint32_t flags,
671 			    unsigned index, unsigned start, unsigned count,
672 			    void *data)
673 {
674 	int (*func)(struct vfio_pci_core_device *vdev, unsigned index,
675 		    unsigned start, unsigned count, uint32_t flags,
676 		    void *data) = NULL;
677 
678 	switch (index) {
679 	case VFIO_PCI_INTX_IRQ_INDEX:
680 		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
681 		case VFIO_IRQ_SET_ACTION_MASK:
682 			func = vfio_pci_set_intx_mask;
683 			break;
684 		case VFIO_IRQ_SET_ACTION_UNMASK:
685 			func = vfio_pci_set_intx_unmask;
686 			break;
687 		case VFIO_IRQ_SET_ACTION_TRIGGER:
688 			func = vfio_pci_set_intx_trigger;
689 			break;
690 		}
691 		break;
692 	case VFIO_PCI_MSI_IRQ_INDEX:
693 	case VFIO_PCI_MSIX_IRQ_INDEX:
694 		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
695 		case VFIO_IRQ_SET_ACTION_MASK:
696 		case VFIO_IRQ_SET_ACTION_UNMASK:
697 			/* XXX Need masking support exported */
698 			break;
699 		case VFIO_IRQ_SET_ACTION_TRIGGER:
700 			func = vfio_pci_set_msi_trigger;
701 			break;
702 		}
703 		break;
704 	case VFIO_PCI_ERR_IRQ_INDEX:
705 		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
706 		case VFIO_IRQ_SET_ACTION_TRIGGER:
707 			if (pci_is_pcie(vdev->pdev))
708 				func = vfio_pci_set_err_trigger;
709 			break;
710 		}
711 		break;
712 	case VFIO_PCI_REQ_IRQ_INDEX:
713 		switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
714 		case VFIO_IRQ_SET_ACTION_TRIGGER:
715 			func = vfio_pci_set_req_trigger;
716 			break;
717 		}
718 		break;
719 	}
720 
721 	if (!func)
722 		return -ENOTTY;
723 
724 	return func(vdev, index, start, count, flags, data);
725 }
726