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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Virtio PCI driver - common functionality for all device versions
  4 *
  5 * This module allows virtio devices to be used over a virtual PCI device.
  6 * This can be used with QEMU based VMMs like KVM or Xen.
  7 *
  8 * Copyright IBM Corp. 2007
  9 * Copyright Red Hat, Inc. 2014
 10 *
 11 * Authors:
 12 *  Anthony Liguori  <aliguori@us.ibm.com>
 13 *  Rusty Russell <rusty@rustcorp.com.au>
 14 *  Michael S. Tsirkin <mst@redhat.com>
 15 */
 16
 17#include "virtio_pci_common.h"
 18
 19static bool force_legacy = false;
 20
 21#if IS_ENABLED(CONFIG_VIRTIO_PCI_LEGACY)
 22module_param(force_legacy, bool, 0444);
 23MODULE_PARM_DESC(force_legacy,
 24		 "Force legacy mode for transitional virtio 1 devices");
 25#endif
 26
 27bool vp_is_avq(struct virtio_device *vdev, unsigned int index)
 28{
 29	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 30
 31	if (!virtio_has_feature(vdev, VIRTIO_F_ADMIN_VQ))
 32		return false;
 33
 34	return index == vp_dev->admin_vq.vq_index;
 35}
 36
 37/* wait for pending irq handlers */
 38void vp_synchronize_vectors(struct virtio_device *vdev)
 39{
 40	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 41	int i;
 42
 43	if (vp_dev->intx_enabled)
 44		synchronize_irq(vp_dev->pci_dev->irq);
 45
 46	for (i = 0; i < vp_dev->msix_vectors; ++i)
 47		synchronize_irq(pci_irq_vector(vp_dev->pci_dev, i));
 48}
 49
 50/* the notify function used when creating a virt queue */
 51bool vp_notify(struct virtqueue *vq)
 52{
 53	/* we write the queue's selector into the notification register to
 54	 * signal the other end */
 55	iowrite16(vq->index, (void __iomem *)vq->priv);
 56	return true;
 57}
 58
 59/* Notify all slow path virtqueues on an interrupt. */
 60static void vp_vring_slow_path_interrupt(int irq,
 61					 struct virtio_pci_device *vp_dev)
 62{
 63	struct virtio_pci_vq_info *info;
 64	unsigned long flags;
 65
 66	spin_lock_irqsave(&vp_dev->lock, flags);
 67	list_for_each_entry(info, &vp_dev->slow_virtqueues, node)
 68		vring_interrupt(irq, info->vq);
 69	spin_unlock_irqrestore(&vp_dev->lock, flags);
 70}
 71
 72/* Handle a configuration change: Tell driver if it wants to know. */
 73static irqreturn_t vp_config_changed(int irq, void *opaque)
 74{
 75	struct virtio_pci_device *vp_dev = opaque;
 76
 77	virtio_config_changed(&vp_dev->vdev);
 78	vp_vring_slow_path_interrupt(irq, vp_dev);
 79	return IRQ_HANDLED;
 80}
 81
 82/* Notify all virtqueues on an interrupt. */
 83static irqreturn_t vp_vring_interrupt(int irq, void *opaque)
 84{
 85	struct virtio_pci_device *vp_dev = opaque;
 86	struct virtio_pci_vq_info *info;
 87	irqreturn_t ret = IRQ_NONE;
 88	unsigned long flags;
 89
 90	spin_lock_irqsave(&vp_dev->lock, flags);
 91	list_for_each_entry(info, &vp_dev->virtqueues, node) {
 92		if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)
 93			ret = IRQ_HANDLED;
 94	}
 95	spin_unlock_irqrestore(&vp_dev->lock, flags);
 96
 97	return ret;
 98}
 99
100/* A small wrapper to also acknowledge the interrupt when it's handled.
101 * I really need an EIO hook for the vring so I can ack the interrupt once we
102 * know that we'll be handling the IRQ but before we invoke the callback since
103 * the callback may notify the host which results in the host attempting to
104 * raise an interrupt that we would then mask once we acknowledged the
105 * interrupt. */
106static irqreturn_t vp_interrupt(int irq, void *opaque)
107{
108	struct virtio_pci_device *vp_dev = opaque;
109	u8 isr;
110
111	/* reading the ISR has the effect of also clearing it so it's very
112	 * important to save off the value. */
113	isr = ioread8(vp_dev->isr);
114
115	/* It's definitely not us if the ISR was not high */
116	if (!isr)
117		return IRQ_NONE;
118
119	/* Configuration change?  Tell driver if it wants to know. */
120	if (isr & VIRTIO_PCI_ISR_CONFIG)
121		vp_config_changed(irq, opaque);
122
123	return vp_vring_interrupt(irq, opaque);
124}
125
126static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors,
127				   bool per_vq_vectors, struct irq_affinity *desc)
128{
129	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
130	const char *name = dev_name(&vp_dev->vdev.dev);
131	unsigned int flags = PCI_IRQ_MSIX;
132	unsigned int i, v;
133	int err = -ENOMEM;
134
135	vp_dev->msix_vectors = nvectors;
136
137	vp_dev->msix_names = kmalloc_array(nvectors,
138					   sizeof(*vp_dev->msix_names),
139					   GFP_KERNEL);
140	if (!vp_dev->msix_names)
141		goto error;
142	vp_dev->msix_affinity_masks
143		= kcalloc(nvectors, sizeof(*vp_dev->msix_affinity_masks),
144			  GFP_KERNEL);
145	if (!vp_dev->msix_affinity_masks)
146		goto error;
147	for (i = 0; i < nvectors; ++i)
148		if (!alloc_cpumask_var(&vp_dev->msix_affinity_masks[i],
149					GFP_KERNEL))
150			goto error;
151
152	if (!per_vq_vectors)
153		desc = NULL;
154
155	if (desc) {
156		flags |= PCI_IRQ_AFFINITY;
157		desc->pre_vectors++; /* virtio config vector */
158	}
159
160	err = pci_alloc_irq_vectors_affinity(vp_dev->pci_dev, nvectors,
161					     nvectors, flags, desc);
162	if (err < 0)
163		goto error;
164	vp_dev->msix_enabled = 1;
165
166	/* Set the vector used for configuration */
167	v = vp_dev->msix_used_vectors;
168	snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
169		 "%s-config", name);
170	err = request_irq(pci_irq_vector(vp_dev->pci_dev, v),
171			  vp_config_changed, 0, vp_dev->msix_names[v],
172			  vp_dev);
173	if (err)
174		goto error;
175	++vp_dev->msix_used_vectors;
176
177	v = vp_dev->config_vector(vp_dev, v);
178	/* Verify we had enough resources to assign the vector */
179	if (v == VIRTIO_MSI_NO_VECTOR) {
180		err = -EBUSY;
181		goto error;
182	}
183
184	if (!per_vq_vectors) {
185		/* Shared vector for all VQs */
186		v = vp_dev->msix_used_vectors;
187		snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
188			 "%s-virtqueues", name);
189		err = request_irq(pci_irq_vector(vp_dev->pci_dev, v),
190				  vp_vring_interrupt, 0, vp_dev->msix_names[v],
191				  vp_dev);
192		if (err)
193			goto error;
194		++vp_dev->msix_used_vectors;
195	}
196	return 0;
197error:
198	return err;
199}
200
201static bool vp_is_slow_path_vector(u16 msix_vec)
202{
203	return msix_vec == VP_MSIX_CONFIG_VECTOR;
204}
205
206static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned int index,
207				     void (*callback)(struct virtqueue *vq),
208				     const char *name,
209				     bool ctx,
210				     u16 msix_vec,
211				     struct virtio_pci_vq_info **p_info)
212{
213	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
214	struct virtio_pci_vq_info *info = kmalloc(sizeof *info, GFP_KERNEL);
215	struct virtqueue *vq;
216	unsigned long flags;
217
218	/* fill out our structure that represents an active queue */
219	if (!info)
220		return ERR_PTR(-ENOMEM);
221
222	vq = vp_dev->setup_vq(vp_dev, info, index, callback, name, ctx,
223			      msix_vec);
224	if (IS_ERR(vq))
225		goto out_info;
226
227	info->vq = vq;
228	if (callback) {
229		spin_lock_irqsave(&vp_dev->lock, flags);
230		if (!vp_is_slow_path_vector(msix_vec))
231			list_add(&info->node, &vp_dev->virtqueues);
232		else
233			list_add(&info->node, &vp_dev->slow_virtqueues);
234		spin_unlock_irqrestore(&vp_dev->lock, flags);
235	} else {
236		INIT_LIST_HEAD(&info->node);
237	}
238
239	*p_info = info;
240	return vq;
241
242out_info:
243	kfree(info);
244	return vq;
245}
246
247static void vp_del_vq(struct virtqueue *vq, struct virtio_pci_vq_info *info)
248{
249	struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
 
250	unsigned long flags;
251
252	/*
253	 * If it fails during re-enable reset vq. This way we won't rejoin
254	 * info->node to the queue. Prevent unexpected irqs.
255	 */
256	if (!vq->reset) {
257		spin_lock_irqsave(&vp_dev->lock, flags);
258		list_del(&info->node);
259		spin_unlock_irqrestore(&vp_dev->lock, flags);
260	}
261
262	vp_dev->del_vq(info);
263	kfree(info);
264}
265
266/* the config->del_vqs() implementation */
267void vp_del_vqs(struct virtio_device *vdev)
268{
269	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
270	struct virtio_pci_vq_info *info;
271	struct virtqueue *vq, *n;
272	int i;
273
274	list_for_each_entry_safe(vq, n, &vdev->vqs, list) {
275		info = vp_is_avq(vdev, vq->index) ? vp_dev->admin_vq.info :
276						    vp_dev->vqs[vq->index];
277
278		if (vp_dev->per_vq_vectors) {
279			int v = info->msix_vector;
280			if (v != VIRTIO_MSI_NO_VECTOR &&
281			    !vp_is_slow_path_vector(v)) {
282				int irq = pci_irq_vector(vp_dev->pci_dev, v);
283
284				irq_update_affinity_hint(irq, NULL);
285				free_irq(irq, vq);
286			}
287		}
288		vp_del_vq(vq, info);
289	}
290	vp_dev->per_vq_vectors = false;
291
292	if (vp_dev->intx_enabled) {
293		free_irq(vp_dev->pci_dev->irq, vp_dev);
294		vp_dev->intx_enabled = 0;
295	}
296
297	for (i = 0; i < vp_dev->msix_used_vectors; ++i)
298		free_irq(pci_irq_vector(vp_dev->pci_dev, i), vp_dev);
299
300	if (vp_dev->msix_affinity_masks) {
301		for (i = 0; i < vp_dev->msix_vectors; i++)
302			free_cpumask_var(vp_dev->msix_affinity_masks[i]);
303	}
304
305	if (vp_dev->msix_enabled) {
306		/* Disable the vector used for configuration */
307		vp_dev->config_vector(vp_dev, VIRTIO_MSI_NO_VECTOR);
308
309		pci_free_irq_vectors(vp_dev->pci_dev);
310		vp_dev->msix_enabled = 0;
311	}
312
313	vp_dev->msix_vectors = 0;
314	vp_dev->msix_used_vectors = 0;
315	kfree(vp_dev->msix_names);
316	vp_dev->msix_names = NULL;
317	kfree(vp_dev->msix_affinity_masks);
318	vp_dev->msix_affinity_masks = NULL;
319	kfree(vp_dev->vqs);
320	vp_dev->vqs = NULL;
321}
322
323enum vp_vq_vector_policy {
324	VP_VQ_VECTOR_POLICY_EACH,
325	VP_VQ_VECTOR_POLICY_SHARED_SLOW,
326	VP_VQ_VECTOR_POLICY_SHARED,
327};
328
329static struct virtqueue *
330vp_find_one_vq_msix(struct virtio_device *vdev, int queue_idx,
331		    vq_callback_t *callback, const char *name, bool ctx,
332		    bool slow_path, int *allocated_vectors,
333		    enum vp_vq_vector_policy vector_policy,
334		    struct virtio_pci_vq_info **p_info)
335{
336	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
337	struct virtqueue *vq;
338	u16 msix_vec;
339	int err;
340
341	if (!callback)
342		msix_vec = VIRTIO_MSI_NO_VECTOR;
343	else if (vector_policy == VP_VQ_VECTOR_POLICY_EACH ||
344		 (vector_policy == VP_VQ_VECTOR_POLICY_SHARED_SLOW &&
345		 !slow_path))
346		msix_vec = (*allocated_vectors)++;
347	else if (vector_policy != VP_VQ_VECTOR_POLICY_EACH &&
348		 slow_path)
349		msix_vec = VP_MSIX_CONFIG_VECTOR;
350	else
351		msix_vec = VP_MSIX_VQ_VECTOR;
352	vq = vp_setup_vq(vdev, queue_idx, callback, name, ctx, msix_vec,
353			 p_info);
354	if (IS_ERR(vq))
355		return vq;
356
357	if (vector_policy == VP_VQ_VECTOR_POLICY_SHARED ||
358	    msix_vec == VIRTIO_MSI_NO_VECTOR ||
359	    vp_is_slow_path_vector(msix_vec))
360		return vq;
361
362	/* allocate per-vq irq if available and necessary */
363	snprintf(vp_dev->msix_names[msix_vec], sizeof(*vp_dev->msix_names),
364		 "%s-%s", dev_name(&vp_dev->vdev.dev), name);
365	err = request_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec),
366			  vring_interrupt, 0,
367			  vp_dev->msix_names[msix_vec], vq);
368	if (err) {
369		vp_del_vq(vq, *p_info);
370		return ERR_PTR(err);
371	}
372
373	return vq;
374}
375
376static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned int nvqs,
377			    struct virtqueue *vqs[],
378			    struct virtqueue_info vqs_info[],
379			    enum vp_vq_vector_policy vector_policy,
380			    struct irq_affinity *desc)
381{
382	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
383	struct virtio_pci_admin_vq *avq = &vp_dev->admin_vq;
384	struct virtqueue_info *vqi;
385	int i, err, nvectors, allocated_vectors, queue_idx = 0;
386	struct virtqueue *vq;
387	bool per_vq_vectors;
388	u16 avq_num = 0;
389
390	vp_dev->vqs = kcalloc(nvqs, sizeof(*vp_dev->vqs), GFP_KERNEL);
391	if (!vp_dev->vqs)
392		return -ENOMEM;
393
394	if (vp_dev->avq_index) {
395		err = vp_dev->avq_index(vdev, &avq->vq_index, &avq_num);
396		if (err)
397			goto error_find;
398	}
399
400	per_vq_vectors = vector_policy != VP_VQ_VECTOR_POLICY_SHARED;
401
402	if (per_vq_vectors) {
403		/* Best option: one for change interrupt, one per vq. */
404		nvectors = 1;
405		for (i = 0; i < nvqs; ++i) {
406			vqi = &vqs_info[i];
407			if (vqi->name && vqi->callback)
408				++nvectors;
409		}
410		if (avq_num && vector_policy == VP_VQ_VECTOR_POLICY_EACH)
411			++nvectors;
412	} else {
413		/* Second best: one for change, shared for all vqs. */
414		nvectors = 2;
415	}
416
417	err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors, desc);
 
418	if (err)
419		goto error_find;
420
421	vp_dev->per_vq_vectors = per_vq_vectors;
422	allocated_vectors = vp_dev->msix_used_vectors;
423	for (i = 0; i < nvqs; ++i) {
424		vqi = &vqs_info[i];
425		if (!vqi->name) {
426			vqs[i] = NULL;
427			continue;
428		}
429		vqs[i] = vp_find_one_vq_msix(vdev, queue_idx++, vqi->callback,
430					     vqi->name, vqi->ctx, false,
431					     &allocated_vectors, vector_policy,
432					     &vp_dev->vqs[i]);
 
 
 
 
 
 
433		if (IS_ERR(vqs[i])) {
434			err = PTR_ERR(vqs[i]);
435			goto error_find;
436		}
437	}
438
439	if (!avq_num)
440		return 0;
441	sprintf(avq->name, "avq.%u", avq->vq_index);
442	vq = vp_find_one_vq_msix(vdev, avq->vq_index, vp_modern_avq_done,
443				 avq->name, false, true, &allocated_vectors,
444				 vector_policy, &vp_dev->admin_vq.info);
445	if (IS_ERR(vq)) {
446		err = PTR_ERR(vq);
447		goto error_find;
448	}
449
 
 
 
 
 
 
 
 
 
 
 
 
 
 
450	return 0;
451
452error_find:
453	vp_del_vqs(vdev);
454	return err;
455}
456
457static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned int nvqs,
458			    struct virtqueue *vqs[],
459			    struct virtqueue_info vqs_info[])
460{
461	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
462	struct virtio_pci_admin_vq *avq = &vp_dev->admin_vq;
463	int i, err, queue_idx = 0;
464	struct virtqueue *vq;
465	u16 avq_num = 0;
466
467	vp_dev->vqs = kcalloc(nvqs, sizeof(*vp_dev->vqs), GFP_KERNEL);
468	if (!vp_dev->vqs)
469		return -ENOMEM;
470
471	if (vp_dev->avq_index) {
472		err = vp_dev->avq_index(vdev, &avq->vq_index, &avq_num);
473		if (err)
474			goto out_del_vqs;
475	}
476
477	err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, IRQF_SHARED,
478			dev_name(&vdev->dev), vp_dev);
479	if (err)
480		goto out_del_vqs;
481
482	vp_dev->intx_enabled = 1;
483	vp_dev->per_vq_vectors = false;
484	for (i = 0; i < nvqs; ++i) {
485		struct virtqueue_info *vqi = &vqs_info[i];
486
487		if (!vqi->name) {
488			vqs[i] = NULL;
489			continue;
490		}
491		vqs[i] = vp_setup_vq(vdev, queue_idx++, vqi->callback,
492				     vqi->name, vqi->ctx,
493				     VIRTIO_MSI_NO_VECTOR, &vp_dev->vqs[i]);
494		if (IS_ERR(vqs[i])) {
495			err = PTR_ERR(vqs[i]);
496			goto out_del_vqs;
497		}
498	}
499
500	if (!avq_num)
501		return 0;
502	sprintf(avq->name, "avq.%u", avq->vq_index);
503	vq = vp_setup_vq(vdev, queue_idx++, vp_modern_avq_done, avq->name,
504			 false, VIRTIO_MSI_NO_VECTOR,
505			 &vp_dev->admin_vq.info);
506	if (IS_ERR(vq)) {
507		err = PTR_ERR(vq);
508		goto out_del_vqs;
509	}
510
511	return 0;
512out_del_vqs:
513	vp_del_vqs(vdev);
514	return err;
515}
516
517/* the config->find_vqs() implementation */
518int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
519		struct virtqueue *vqs[], struct virtqueue_info vqs_info[],
 
520		struct irq_affinity *desc)
521{
522	int err;
523
524	/* Try MSI-X with one vector per queue. */
525	err = vp_find_vqs_msix(vdev, nvqs, vqs, vqs_info,
526			       VP_VQ_VECTOR_POLICY_EACH, desc);
527	if (!err)
528		return 0;
529	/* Fallback: MSI-X with one shared vector for config and
530	 * slow path queues, one vector per queue for the rest.
531	 */
532	err = vp_find_vqs_msix(vdev, nvqs, vqs, vqs_info,
533			       VP_VQ_VECTOR_POLICY_SHARED_SLOW, desc);
534	if (!err)
535		return 0;
536	/* Fallback: MSI-X with one vector for config, one shared for queues. */
537	err = vp_find_vqs_msix(vdev, nvqs, vqs, vqs_info,
538			       VP_VQ_VECTOR_POLICY_SHARED, desc);
539	if (!err)
540		return 0;
541	/* Is there an interrupt? If not give up. */
542	if (!(to_vp_device(vdev)->pci_dev->irq))
543		return err;
544	/* Finally fall back to regular interrupts. */
545	return vp_find_vqs_intx(vdev, nvqs, vqs, vqs_info);
546}
547
548const char *vp_bus_name(struct virtio_device *vdev)
549{
550	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
551
552	return pci_name(vp_dev->pci_dev);
553}
554
555/* Setup the affinity for a virtqueue:
556 * - force the affinity for per vq vector
557 * - OR over all affinities for shared MSI
558 * - ignore the affinity request if we're using INTX
559 */
560int vp_set_vq_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask)
561{
562	struct virtio_device *vdev = vq->vdev;
563	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
564	struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index];
565	struct cpumask *mask;
566	unsigned int irq;
567
568	if (!vq->callback)
569		return -EINVAL;
570
571	if (vp_dev->msix_enabled) {
572		mask = vp_dev->msix_affinity_masks[info->msix_vector];
573		irq = pci_irq_vector(vp_dev->pci_dev, info->msix_vector);
574		if (!cpu_mask)
575			irq_update_affinity_hint(irq, NULL);
576		else {
577			cpumask_copy(mask, cpu_mask);
578			irq_set_affinity_and_hint(irq, mask);
579		}
580	}
581	return 0;
582}
583
584const struct cpumask *vp_get_vq_affinity(struct virtio_device *vdev, int index)
585{
586	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
587
588	if (!vp_dev->per_vq_vectors ||
589	    vp_dev->vqs[index]->msix_vector == VIRTIO_MSI_NO_VECTOR ||
590	    vp_is_slow_path_vector(vp_dev->vqs[index]->msix_vector))
591		return NULL;
592
593	return pci_irq_get_affinity(vp_dev->pci_dev,
594				    vp_dev->vqs[index]->msix_vector);
595}
596
597#ifdef CONFIG_PM_SLEEP
598static int virtio_pci_freeze(struct device *dev)
599{
600	struct pci_dev *pci_dev = to_pci_dev(dev);
601	struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
602	int ret;
603
604	ret = virtio_device_freeze(&vp_dev->vdev);
605
606	if (!ret)
607		pci_disable_device(pci_dev);
608	return ret;
609}
610
611static int virtio_pci_restore(struct device *dev)
612{
613	struct pci_dev *pci_dev = to_pci_dev(dev);
614	struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
615	int ret;
616
617	ret = pci_enable_device(pci_dev);
618	if (ret)
619		return ret;
620
621	pci_set_master(pci_dev);
622	return virtio_device_restore(&vp_dev->vdev);
623}
624
625static bool vp_supports_pm_no_reset(struct device *dev)
626{
627	struct pci_dev *pci_dev = to_pci_dev(dev);
628	u16 pmcsr;
629
630	if (!pci_dev->pm_cap)
631		return false;
632
633	pci_read_config_word(pci_dev, pci_dev->pm_cap + PCI_PM_CTRL, &pmcsr);
634	if (PCI_POSSIBLE_ERROR(pmcsr)) {
635		dev_err(dev, "Unable to query pmcsr");
636		return false;
637	}
638
639	return pmcsr & PCI_PM_CTRL_NO_SOFT_RESET;
640}
641
642static int virtio_pci_suspend(struct device *dev)
643{
644	return vp_supports_pm_no_reset(dev) ? 0 : virtio_pci_freeze(dev);
645}
646
647static int virtio_pci_resume(struct device *dev)
648{
649	return vp_supports_pm_no_reset(dev) ? 0 : virtio_pci_restore(dev);
650}
651
652static const struct dev_pm_ops virtio_pci_pm_ops = {
653	.suspend = virtio_pci_suspend,
654	.resume = virtio_pci_resume,
655	.freeze = virtio_pci_freeze,
656	.thaw = virtio_pci_restore,
657	.poweroff = virtio_pci_freeze,
658	.restore = virtio_pci_restore,
659};
660#endif
661
662
663/* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */
664static const struct pci_device_id virtio_pci_id_table[] = {
665	{ PCI_DEVICE(PCI_VENDOR_ID_REDHAT_QUMRANET, PCI_ANY_ID) },
666	{ 0 }
667};
668
669MODULE_DEVICE_TABLE(pci, virtio_pci_id_table);
670
671static void virtio_pci_release_dev(struct device *_d)
672{
673	struct virtio_device *vdev = dev_to_virtio(_d);
674	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
675
676	/* As struct device is a kobject, it's not safe to
677	 * free the memory (including the reference counter itself)
678	 * until it's release callback. */
679	kfree(vp_dev);
680}
681
682static int virtio_pci_probe(struct pci_dev *pci_dev,
683			    const struct pci_device_id *id)
684{
685	struct virtio_pci_device *vp_dev, *reg_dev = NULL;
686	int rc;
687
688	/* allocate our structure and fill it out */
689	vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL);
690	if (!vp_dev)
691		return -ENOMEM;
692
693	pci_set_drvdata(pci_dev, vp_dev);
694	vp_dev->vdev.dev.parent = &pci_dev->dev;
695	vp_dev->vdev.dev.release = virtio_pci_release_dev;
696	vp_dev->pci_dev = pci_dev;
697	INIT_LIST_HEAD(&vp_dev->virtqueues);
698	INIT_LIST_HEAD(&vp_dev->slow_virtqueues);
699	spin_lock_init(&vp_dev->lock);
700
701	/* enable the device */
702	rc = pci_enable_device(pci_dev);
703	if (rc)
704		goto err_enable_device;
705
706	if (force_legacy) {
707		rc = virtio_pci_legacy_probe(vp_dev);
708		/* Also try modern mode if we can't map BAR0 (no IO space). */
709		if (rc == -ENODEV || rc == -ENOMEM)
710			rc = virtio_pci_modern_probe(vp_dev);
711		if (rc)
712			goto err_probe;
713	} else {
714		rc = virtio_pci_modern_probe(vp_dev);
715		if (rc == -ENODEV)
716			rc = virtio_pci_legacy_probe(vp_dev);
717		if (rc)
718			goto err_probe;
719	}
720
721	pci_set_master(pci_dev);
722
723	rc = register_virtio_device(&vp_dev->vdev);
724	reg_dev = vp_dev;
725	if (rc)
726		goto err_register;
727
728	return 0;
729
730err_register:
731	if (vp_dev->is_legacy)
732		virtio_pci_legacy_remove(vp_dev);
733	else
734		virtio_pci_modern_remove(vp_dev);
735err_probe:
736	pci_disable_device(pci_dev);
737err_enable_device:
738	if (reg_dev)
739		put_device(&vp_dev->vdev.dev);
740	else
741		kfree(vp_dev);
742	return rc;
743}
744
745static void virtio_pci_remove(struct pci_dev *pci_dev)
746{
747	struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
748	struct device *dev = get_device(&vp_dev->vdev.dev);
749
750	/*
751	 * Device is marked broken on surprise removal so that virtio upper
752	 * layers can abort any ongoing operation.
753	 */
754	if (!pci_device_is_present(pci_dev))
755		virtio_break_device(&vp_dev->vdev);
756
757	pci_disable_sriov(pci_dev);
758
759	unregister_virtio_device(&vp_dev->vdev);
760
761	if (vp_dev->is_legacy)
762		virtio_pci_legacy_remove(vp_dev);
763	else
764		virtio_pci_modern_remove(vp_dev);
765
766	pci_disable_device(pci_dev);
767	put_device(dev);
768}
769
770static int virtio_pci_sriov_configure(struct pci_dev *pci_dev, int num_vfs)
771{
772	struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
773	struct virtio_device *vdev = &vp_dev->vdev;
774	int ret;
775
776	if (!(vdev->config->get_status(vdev) & VIRTIO_CONFIG_S_DRIVER_OK))
777		return -EBUSY;
778
779	if (!__virtio_test_bit(vdev, VIRTIO_F_SR_IOV))
780		return -EINVAL;
781
782	if (pci_vfs_assigned(pci_dev))
783		return -EPERM;
784
785	if (num_vfs == 0) {
786		pci_disable_sriov(pci_dev);
787		return 0;
788	}
789
790	ret = pci_enable_sriov(pci_dev, num_vfs);
791	if (ret < 0)
792		return ret;
793
794	return num_vfs;
795}
796
797static struct pci_driver virtio_pci_driver = {
798	.name		= "virtio-pci",
799	.id_table	= virtio_pci_id_table,
800	.probe		= virtio_pci_probe,
801	.remove		= virtio_pci_remove,
802#ifdef CONFIG_PM_SLEEP
803	.driver.pm	= &virtio_pci_pm_ops,
804#endif
805	.sriov_configure = virtio_pci_sriov_configure,
806};
807
808struct virtio_device *virtio_pci_vf_get_pf_dev(struct pci_dev *pdev)
809{
810	struct virtio_pci_device *pf_vp_dev;
811
812	pf_vp_dev = pci_iov_get_pf_drvdata(pdev, &virtio_pci_driver);
813	if (IS_ERR(pf_vp_dev))
814		return NULL;
815
816	return &pf_vp_dev->vdev;
817}
818
819module_pci_driver(virtio_pci_driver);
820
821MODULE_AUTHOR("Anthony Liguori <aliguori@us.ibm.com>");
822MODULE_DESCRIPTION("virtio-pci");
823MODULE_LICENSE("GPL");
824MODULE_VERSION("1");
v6.9.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Virtio PCI driver - common functionality for all device versions
  4 *
  5 * This module allows virtio devices to be used over a virtual PCI device.
  6 * This can be used with QEMU based VMMs like KVM or Xen.
  7 *
  8 * Copyright IBM Corp. 2007
  9 * Copyright Red Hat, Inc. 2014
 10 *
 11 * Authors:
 12 *  Anthony Liguori  <aliguori@us.ibm.com>
 13 *  Rusty Russell <rusty@rustcorp.com.au>
 14 *  Michael S. Tsirkin <mst@redhat.com>
 15 */
 16
 17#include "virtio_pci_common.h"
 18
 19static bool force_legacy = false;
 20
 21#if IS_ENABLED(CONFIG_VIRTIO_PCI_LEGACY)
 22module_param(force_legacy, bool, 0444);
 23MODULE_PARM_DESC(force_legacy,
 24		 "Force legacy mode for transitional virtio 1 devices");
 25#endif
 26
 
 
 
 
 
 
 
 
 
 
 27/* wait for pending irq handlers */
 28void vp_synchronize_vectors(struct virtio_device *vdev)
 29{
 30	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 31	int i;
 32
 33	if (vp_dev->intx_enabled)
 34		synchronize_irq(vp_dev->pci_dev->irq);
 35
 36	for (i = 0; i < vp_dev->msix_vectors; ++i)
 37		synchronize_irq(pci_irq_vector(vp_dev->pci_dev, i));
 38}
 39
 40/* the notify function used when creating a virt queue */
 41bool vp_notify(struct virtqueue *vq)
 42{
 43	/* we write the queue's selector into the notification register to
 44	 * signal the other end */
 45	iowrite16(vq->index, (void __iomem *)vq->priv);
 46	return true;
 47}
 48
 
 
 
 
 
 
 
 
 
 
 
 
 
 49/* Handle a configuration change: Tell driver if it wants to know. */
 50static irqreturn_t vp_config_changed(int irq, void *opaque)
 51{
 52	struct virtio_pci_device *vp_dev = opaque;
 53
 54	virtio_config_changed(&vp_dev->vdev);
 
 55	return IRQ_HANDLED;
 56}
 57
 58/* Notify all virtqueues on an interrupt. */
 59static irqreturn_t vp_vring_interrupt(int irq, void *opaque)
 60{
 61	struct virtio_pci_device *vp_dev = opaque;
 62	struct virtio_pci_vq_info *info;
 63	irqreturn_t ret = IRQ_NONE;
 64	unsigned long flags;
 65
 66	spin_lock_irqsave(&vp_dev->lock, flags);
 67	list_for_each_entry(info, &vp_dev->virtqueues, node) {
 68		if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)
 69			ret = IRQ_HANDLED;
 70	}
 71	spin_unlock_irqrestore(&vp_dev->lock, flags);
 72
 73	return ret;
 74}
 75
 76/* A small wrapper to also acknowledge the interrupt when it's handled.
 77 * I really need an EIO hook for the vring so I can ack the interrupt once we
 78 * know that we'll be handling the IRQ but before we invoke the callback since
 79 * the callback may notify the host which results in the host attempting to
 80 * raise an interrupt that we would then mask once we acknowledged the
 81 * interrupt. */
 82static irqreturn_t vp_interrupt(int irq, void *opaque)
 83{
 84	struct virtio_pci_device *vp_dev = opaque;
 85	u8 isr;
 86
 87	/* reading the ISR has the effect of also clearing it so it's very
 88	 * important to save off the value. */
 89	isr = ioread8(vp_dev->isr);
 90
 91	/* It's definitely not us if the ISR was not high */
 92	if (!isr)
 93		return IRQ_NONE;
 94
 95	/* Configuration change?  Tell driver if it wants to know. */
 96	if (isr & VIRTIO_PCI_ISR_CONFIG)
 97		vp_config_changed(irq, opaque);
 98
 99	return vp_vring_interrupt(irq, opaque);
100}
101
102static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors,
103				   bool per_vq_vectors, struct irq_affinity *desc)
104{
105	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
106	const char *name = dev_name(&vp_dev->vdev.dev);
107	unsigned int flags = PCI_IRQ_MSIX;
108	unsigned int i, v;
109	int err = -ENOMEM;
110
111	vp_dev->msix_vectors = nvectors;
112
113	vp_dev->msix_names = kmalloc_array(nvectors,
114					   sizeof(*vp_dev->msix_names),
115					   GFP_KERNEL);
116	if (!vp_dev->msix_names)
117		goto error;
118	vp_dev->msix_affinity_masks
119		= kcalloc(nvectors, sizeof(*vp_dev->msix_affinity_masks),
120			  GFP_KERNEL);
121	if (!vp_dev->msix_affinity_masks)
122		goto error;
123	for (i = 0; i < nvectors; ++i)
124		if (!alloc_cpumask_var(&vp_dev->msix_affinity_masks[i],
125					GFP_KERNEL))
126			goto error;
127
 
 
 
128	if (desc) {
129		flags |= PCI_IRQ_AFFINITY;
130		desc->pre_vectors++; /* virtio config vector */
131	}
132
133	err = pci_alloc_irq_vectors_affinity(vp_dev->pci_dev, nvectors,
134					     nvectors, flags, desc);
135	if (err < 0)
136		goto error;
137	vp_dev->msix_enabled = 1;
138
139	/* Set the vector used for configuration */
140	v = vp_dev->msix_used_vectors;
141	snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
142		 "%s-config", name);
143	err = request_irq(pci_irq_vector(vp_dev->pci_dev, v),
144			  vp_config_changed, 0, vp_dev->msix_names[v],
145			  vp_dev);
146	if (err)
147		goto error;
148	++vp_dev->msix_used_vectors;
149
150	v = vp_dev->config_vector(vp_dev, v);
151	/* Verify we had enough resources to assign the vector */
152	if (v == VIRTIO_MSI_NO_VECTOR) {
153		err = -EBUSY;
154		goto error;
155	}
156
157	if (!per_vq_vectors) {
158		/* Shared vector for all VQs */
159		v = vp_dev->msix_used_vectors;
160		snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
161			 "%s-virtqueues", name);
162		err = request_irq(pci_irq_vector(vp_dev->pci_dev, v),
163				  vp_vring_interrupt, 0, vp_dev->msix_names[v],
164				  vp_dev);
165		if (err)
166			goto error;
167		++vp_dev->msix_used_vectors;
168	}
169	return 0;
170error:
171	return err;
172}
173
 
 
 
 
 
174static struct virtqueue *vp_setup_vq(struct virtio_device *vdev, unsigned int index,
175				     void (*callback)(struct virtqueue *vq),
176				     const char *name,
177				     bool ctx,
178				     u16 msix_vec)
 
179{
180	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
181	struct virtio_pci_vq_info *info = kmalloc(sizeof *info, GFP_KERNEL);
182	struct virtqueue *vq;
183	unsigned long flags;
184
185	/* fill out our structure that represents an active queue */
186	if (!info)
187		return ERR_PTR(-ENOMEM);
188
189	vq = vp_dev->setup_vq(vp_dev, info, index, callback, name, ctx,
190			      msix_vec);
191	if (IS_ERR(vq))
192		goto out_info;
193
194	info->vq = vq;
195	if (callback) {
196		spin_lock_irqsave(&vp_dev->lock, flags);
197		list_add(&info->node, &vp_dev->virtqueues);
 
 
 
198		spin_unlock_irqrestore(&vp_dev->lock, flags);
199	} else {
200		INIT_LIST_HEAD(&info->node);
201	}
202
203	vp_dev->vqs[index] = info;
204	return vq;
205
206out_info:
207	kfree(info);
208	return vq;
209}
210
211static void vp_del_vq(struct virtqueue *vq)
212{
213	struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
214	struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index];
215	unsigned long flags;
216
217	/*
218	 * If it fails during re-enable reset vq. This way we won't rejoin
219	 * info->node to the queue. Prevent unexpected irqs.
220	 */
221	if (!vq->reset) {
222		spin_lock_irqsave(&vp_dev->lock, flags);
223		list_del(&info->node);
224		spin_unlock_irqrestore(&vp_dev->lock, flags);
225	}
226
227	vp_dev->del_vq(info);
228	kfree(info);
229}
230
231/* the config->del_vqs() implementation */
232void vp_del_vqs(struct virtio_device *vdev)
233{
234	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 
235	struct virtqueue *vq, *n;
236	int i;
237
238	list_for_each_entry_safe(vq, n, &vdev->vqs, list) {
239		if (vp_dev->is_avq(vdev, vq->index))
240			continue;
241
242		if (vp_dev->per_vq_vectors) {
243			int v = vp_dev->vqs[vq->index]->msix_vector;
244
245			if (v != VIRTIO_MSI_NO_VECTOR) {
246				int irq = pci_irq_vector(vp_dev->pci_dev, v);
247
248				irq_update_affinity_hint(irq, NULL);
249				free_irq(irq, vq);
250			}
251		}
252		vp_del_vq(vq);
253	}
254	vp_dev->per_vq_vectors = false;
255
256	if (vp_dev->intx_enabled) {
257		free_irq(vp_dev->pci_dev->irq, vp_dev);
258		vp_dev->intx_enabled = 0;
259	}
260
261	for (i = 0; i < vp_dev->msix_used_vectors; ++i)
262		free_irq(pci_irq_vector(vp_dev->pci_dev, i), vp_dev);
263
264	if (vp_dev->msix_affinity_masks) {
265		for (i = 0; i < vp_dev->msix_vectors; i++)
266			free_cpumask_var(vp_dev->msix_affinity_masks[i]);
267	}
268
269	if (vp_dev->msix_enabled) {
270		/* Disable the vector used for configuration */
271		vp_dev->config_vector(vp_dev, VIRTIO_MSI_NO_VECTOR);
272
273		pci_free_irq_vectors(vp_dev->pci_dev);
274		vp_dev->msix_enabled = 0;
275	}
276
277	vp_dev->msix_vectors = 0;
278	vp_dev->msix_used_vectors = 0;
279	kfree(vp_dev->msix_names);
280	vp_dev->msix_names = NULL;
281	kfree(vp_dev->msix_affinity_masks);
282	vp_dev->msix_affinity_masks = NULL;
283	kfree(vp_dev->vqs);
284	vp_dev->vqs = NULL;
285}
286
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
287static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned int nvqs,
288		struct virtqueue *vqs[], vq_callback_t *callbacks[],
289		const char * const names[], bool per_vq_vectors,
290		const bool *ctx,
291		struct irq_affinity *desc)
292{
293	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
294	u16 msix_vec;
 
295	int i, err, nvectors, allocated_vectors, queue_idx = 0;
 
 
 
296
297	vp_dev->vqs = kcalloc(nvqs, sizeof(*vp_dev->vqs), GFP_KERNEL);
298	if (!vp_dev->vqs)
299		return -ENOMEM;
300
 
 
 
 
 
 
 
 
301	if (per_vq_vectors) {
302		/* Best option: one for change interrupt, one per vq. */
303		nvectors = 1;
304		for (i = 0; i < nvqs; ++i)
305			if (names[i] && callbacks[i])
 
306				++nvectors;
 
 
 
307	} else {
308		/* Second best: one for change, shared for all vqs. */
309		nvectors = 2;
310	}
311
312	err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors,
313				      per_vq_vectors ? desc : NULL);
314	if (err)
315		goto error_find;
316
317	vp_dev->per_vq_vectors = per_vq_vectors;
318	allocated_vectors = vp_dev->msix_used_vectors;
319	for (i = 0; i < nvqs; ++i) {
320		if (!names[i]) {
 
321			vqs[i] = NULL;
322			continue;
323		}
324
325		if (!callbacks[i])
326			msix_vec = VIRTIO_MSI_NO_VECTOR;
327		else if (vp_dev->per_vq_vectors)
328			msix_vec = allocated_vectors++;
329		else
330			msix_vec = VP_MSIX_VQ_VECTOR;
331		vqs[i] = vp_setup_vq(vdev, queue_idx++, callbacks[i], names[i],
332				     ctx ? ctx[i] : false,
333				     msix_vec);
334		if (IS_ERR(vqs[i])) {
335			err = PTR_ERR(vqs[i]);
336			goto error_find;
337		}
 
338
339		if (!vp_dev->per_vq_vectors || msix_vec == VIRTIO_MSI_NO_VECTOR)
340			continue;
 
 
 
 
 
 
 
 
341
342		/* allocate per-vq irq if available and necessary */
343		snprintf(vp_dev->msix_names[msix_vec],
344			 sizeof *vp_dev->msix_names,
345			 "%s-%s",
346			 dev_name(&vp_dev->vdev.dev), names[i]);
347		err = request_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec),
348				  vring_interrupt, 0,
349				  vp_dev->msix_names[msix_vec],
350				  vqs[i]);
351		if (err) {
352			vp_del_vq(vqs[i]);
353			goto error_find;
354		}
355	}
356	return 0;
357
358error_find:
359	vp_del_vqs(vdev);
360	return err;
361}
362
363static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned int nvqs,
364		struct virtqueue *vqs[], vq_callback_t *callbacks[],
365		const char * const names[], const bool *ctx)
366{
367	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
 
368	int i, err, queue_idx = 0;
 
 
369
370	vp_dev->vqs = kcalloc(nvqs, sizeof(*vp_dev->vqs), GFP_KERNEL);
371	if (!vp_dev->vqs)
372		return -ENOMEM;
373
 
 
 
 
 
 
374	err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, IRQF_SHARED,
375			dev_name(&vdev->dev), vp_dev);
376	if (err)
377		goto out_del_vqs;
378
379	vp_dev->intx_enabled = 1;
380	vp_dev->per_vq_vectors = false;
381	for (i = 0; i < nvqs; ++i) {
382		if (!names[i]) {
 
 
383			vqs[i] = NULL;
384			continue;
385		}
386		vqs[i] = vp_setup_vq(vdev, queue_idx++, callbacks[i], names[i],
387				     ctx ? ctx[i] : false,
388				     VIRTIO_MSI_NO_VECTOR);
389		if (IS_ERR(vqs[i])) {
390			err = PTR_ERR(vqs[i]);
391			goto out_del_vqs;
392		}
393	}
394
 
 
 
 
 
 
 
 
 
 
 
395	return 0;
396out_del_vqs:
397	vp_del_vqs(vdev);
398	return err;
399}
400
401/* the config->find_vqs() implementation */
402int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
403		struct virtqueue *vqs[], vq_callback_t *callbacks[],
404		const char * const names[], const bool *ctx,
405		struct irq_affinity *desc)
406{
407	int err;
408
409	/* Try MSI-X with one vector per queue. */
410	err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, true, ctx, desc);
 
 
 
 
 
 
 
 
411	if (!err)
412		return 0;
413	/* Fallback: MSI-X with one vector for config, one shared for queues. */
414	err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, false, ctx, desc);
 
415	if (!err)
416		return 0;
417	/* Is there an interrupt? If not give up. */
418	if (!(to_vp_device(vdev)->pci_dev->irq))
419		return err;
420	/* Finally fall back to regular interrupts. */
421	return vp_find_vqs_intx(vdev, nvqs, vqs, callbacks, names, ctx);
422}
423
424const char *vp_bus_name(struct virtio_device *vdev)
425{
426	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
427
428	return pci_name(vp_dev->pci_dev);
429}
430
431/* Setup the affinity for a virtqueue:
432 * - force the affinity for per vq vector
433 * - OR over all affinities for shared MSI
434 * - ignore the affinity request if we're using INTX
435 */
436int vp_set_vq_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask)
437{
438	struct virtio_device *vdev = vq->vdev;
439	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
440	struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index];
441	struct cpumask *mask;
442	unsigned int irq;
443
444	if (!vq->callback)
445		return -EINVAL;
446
447	if (vp_dev->msix_enabled) {
448		mask = vp_dev->msix_affinity_masks[info->msix_vector];
449		irq = pci_irq_vector(vp_dev->pci_dev, info->msix_vector);
450		if (!cpu_mask)
451			irq_update_affinity_hint(irq, NULL);
452		else {
453			cpumask_copy(mask, cpu_mask);
454			irq_set_affinity_and_hint(irq, mask);
455		}
456	}
457	return 0;
458}
459
460const struct cpumask *vp_get_vq_affinity(struct virtio_device *vdev, int index)
461{
462	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
463
464	if (!vp_dev->per_vq_vectors ||
465	    vp_dev->vqs[index]->msix_vector == VIRTIO_MSI_NO_VECTOR)
 
466		return NULL;
467
468	return pci_irq_get_affinity(vp_dev->pci_dev,
469				    vp_dev->vqs[index]->msix_vector);
470}
471
472#ifdef CONFIG_PM_SLEEP
473static int virtio_pci_freeze(struct device *dev)
474{
475	struct pci_dev *pci_dev = to_pci_dev(dev);
476	struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
477	int ret;
478
479	ret = virtio_device_freeze(&vp_dev->vdev);
480
481	if (!ret)
482		pci_disable_device(pci_dev);
483	return ret;
484}
485
486static int virtio_pci_restore(struct device *dev)
487{
488	struct pci_dev *pci_dev = to_pci_dev(dev);
489	struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
490	int ret;
491
492	ret = pci_enable_device(pci_dev);
493	if (ret)
494		return ret;
495
496	pci_set_master(pci_dev);
497	return virtio_device_restore(&vp_dev->vdev);
498}
499
500static bool vp_supports_pm_no_reset(struct device *dev)
501{
502	struct pci_dev *pci_dev = to_pci_dev(dev);
503	u16 pmcsr;
504
505	if (!pci_dev->pm_cap)
506		return false;
507
508	pci_read_config_word(pci_dev, pci_dev->pm_cap + PCI_PM_CTRL, &pmcsr);
509	if (PCI_POSSIBLE_ERROR(pmcsr)) {
510		dev_err(dev, "Unable to query pmcsr");
511		return false;
512	}
513
514	return pmcsr & PCI_PM_CTRL_NO_SOFT_RESET;
515}
516
517static int virtio_pci_suspend(struct device *dev)
518{
519	return vp_supports_pm_no_reset(dev) ? 0 : virtio_pci_freeze(dev);
520}
521
522static int virtio_pci_resume(struct device *dev)
523{
524	return vp_supports_pm_no_reset(dev) ? 0 : virtio_pci_restore(dev);
525}
526
527static const struct dev_pm_ops virtio_pci_pm_ops = {
528	.suspend = virtio_pci_suspend,
529	.resume = virtio_pci_resume,
530	.freeze = virtio_pci_freeze,
531	.thaw = virtio_pci_restore,
532	.poweroff = virtio_pci_freeze,
533	.restore = virtio_pci_restore,
534};
535#endif
536
537
538/* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */
539static const struct pci_device_id virtio_pci_id_table[] = {
540	{ PCI_DEVICE(PCI_VENDOR_ID_REDHAT_QUMRANET, PCI_ANY_ID) },
541	{ 0 }
542};
543
544MODULE_DEVICE_TABLE(pci, virtio_pci_id_table);
545
546static void virtio_pci_release_dev(struct device *_d)
547{
548	struct virtio_device *vdev = dev_to_virtio(_d);
549	struct virtio_pci_device *vp_dev = to_vp_device(vdev);
550
551	/* As struct device is a kobject, it's not safe to
552	 * free the memory (including the reference counter itself)
553	 * until it's release callback. */
554	kfree(vp_dev);
555}
556
557static int virtio_pci_probe(struct pci_dev *pci_dev,
558			    const struct pci_device_id *id)
559{
560	struct virtio_pci_device *vp_dev, *reg_dev = NULL;
561	int rc;
562
563	/* allocate our structure and fill it out */
564	vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL);
565	if (!vp_dev)
566		return -ENOMEM;
567
568	pci_set_drvdata(pci_dev, vp_dev);
569	vp_dev->vdev.dev.parent = &pci_dev->dev;
570	vp_dev->vdev.dev.release = virtio_pci_release_dev;
571	vp_dev->pci_dev = pci_dev;
572	INIT_LIST_HEAD(&vp_dev->virtqueues);
 
573	spin_lock_init(&vp_dev->lock);
574
575	/* enable the device */
576	rc = pci_enable_device(pci_dev);
577	if (rc)
578		goto err_enable_device;
579
580	if (force_legacy) {
581		rc = virtio_pci_legacy_probe(vp_dev);
582		/* Also try modern mode if we can't map BAR0 (no IO space). */
583		if (rc == -ENODEV || rc == -ENOMEM)
584			rc = virtio_pci_modern_probe(vp_dev);
585		if (rc)
586			goto err_probe;
587	} else {
588		rc = virtio_pci_modern_probe(vp_dev);
589		if (rc == -ENODEV)
590			rc = virtio_pci_legacy_probe(vp_dev);
591		if (rc)
592			goto err_probe;
593	}
594
595	pci_set_master(pci_dev);
596
597	rc = register_virtio_device(&vp_dev->vdev);
598	reg_dev = vp_dev;
599	if (rc)
600		goto err_register;
601
602	return 0;
603
604err_register:
605	if (vp_dev->is_legacy)
606		virtio_pci_legacy_remove(vp_dev);
607	else
608		virtio_pci_modern_remove(vp_dev);
609err_probe:
610	pci_disable_device(pci_dev);
611err_enable_device:
612	if (reg_dev)
613		put_device(&vp_dev->vdev.dev);
614	else
615		kfree(vp_dev);
616	return rc;
617}
618
619static void virtio_pci_remove(struct pci_dev *pci_dev)
620{
621	struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
622	struct device *dev = get_device(&vp_dev->vdev.dev);
623
624	/*
625	 * Device is marked broken on surprise removal so that virtio upper
626	 * layers can abort any ongoing operation.
627	 */
628	if (!pci_device_is_present(pci_dev))
629		virtio_break_device(&vp_dev->vdev);
630
631	pci_disable_sriov(pci_dev);
632
633	unregister_virtio_device(&vp_dev->vdev);
634
635	if (vp_dev->is_legacy)
636		virtio_pci_legacy_remove(vp_dev);
637	else
638		virtio_pci_modern_remove(vp_dev);
639
640	pci_disable_device(pci_dev);
641	put_device(dev);
642}
643
644static int virtio_pci_sriov_configure(struct pci_dev *pci_dev, int num_vfs)
645{
646	struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
647	struct virtio_device *vdev = &vp_dev->vdev;
648	int ret;
649
650	if (!(vdev->config->get_status(vdev) & VIRTIO_CONFIG_S_DRIVER_OK))
651		return -EBUSY;
652
653	if (!__virtio_test_bit(vdev, VIRTIO_F_SR_IOV))
654		return -EINVAL;
655
656	if (pci_vfs_assigned(pci_dev))
657		return -EPERM;
658
659	if (num_vfs == 0) {
660		pci_disable_sriov(pci_dev);
661		return 0;
662	}
663
664	ret = pci_enable_sriov(pci_dev, num_vfs);
665	if (ret < 0)
666		return ret;
667
668	return num_vfs;
669}
670
671static struct pci_driver virtio_pci_driver = {
672	.name		= "virtio-pci",
673	.id_table	= virtio_pci_id_table,
674	.probe		= virtio_pci_probe,
675	.remove		= virtio_pci_remove,
676#ifdef CONFIG_PM_SLEEP
677	.driver.pm	= &virtio_pci_pm_ops,
678#endif
679	.sriov_configure = virtio_pci_sriov_configure,
680};
681
682struct virtio_device *virtio_pci_vf_get_pf_dev(struct pci_dev *pdev)
683{
684	struct virtio_pci_device *pf_vp_dev;
685
686	pf_vp_dev = pci_iov_get_pf_drvdata(pdev, &virtio_pci_driver);
687	if (IS_ERR(pf_vp_dev))
688		return NULL;
689
690	return &pf_vp_dev->vdev;
691}
692
693module_pci_driver(virtio_pci_driver);
694
695MODULE_AUTHOR("Anthony Liguori <aliguori@us.ibm.com>");
696MODULE_DESCRIPTION("virtio-pci");
697MODULE_LICENSE("GPL");
698MODULE_VERSION("1");