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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");
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->per_vq_vectors) {
240 int v = vp_dev->vqs[vq->index]->msix_vector;
241
242 if (v != VIRTIO_MSI_NO_VECTOR) {
243 int irq = pci_irq_vector(vp_dev->pci_dev, v);
244
245 irq_set_affinity_hint(irq, NULL);
246 free_irq(irq, vq);
247 }
248 }
249 vp_del_vq(vq);
250 }
251 vp_dev->per_vq_vectors = false;
252
253 if (vp_dev->intx_enabled) {
254 free_irq(vp_dev->pci_dev->irq, vp_dev);
255 vp_dev->intx_enabled = 0;
256 }
257
258 for (i = 0; i < vp_dev->msix_used_vectors; ++i)
259 free_irq(pci_irq_vector(vp_dev->pci_dev, i), vp_dev);
260
261 if (vp_dev->msix_affinity_masks) {
262 for (i = 0; i < vp_dev->msix_vectors; i++)
263 free_cpumask_var(vp_dev->msix_affinity_masks[i]);
264 }
265
266 if (vp_dev->msix_enabled) {
267 /* Disable the vector used for configuration */
268 vp_dev->config_vector(vp_dev, VIRTIO_MSI_NO_VECTOR);
269
270 pci_free_irq_vectors(vp_dev->pci_dev);
271 vp_dev->msix_enabled = 0;
272 }
273
274 vp_dev->msix_vectors = 0;
275 vp_dev->msix_used_vectors = 0;
276 kfree(vp_dev->msix_names);
277 vp_dev->msix_names = NULL;
278 kfree(vp_dev->msix_affinity_masks);
279 vp_dev->msix_affinity_masks = NULL;
280 kfree(vp_dev->vqs);
281 vp_dev->vqs = NULL;
282}
283
284static int vp_find_vqs_msix(struct virtio_device *vdev, unsigned int nvqs,
285 struct virtqueue *vqs[], vq_callback_t *callbacks[],
286 const char * const names[], bool per_vq_vectors,
287 const bool *ctx,
288 struct irq_affinity *desc)
289{
290 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
291 u16 msix_vec;
292 int i, err, nvectors, allocated_vectors, queue_idx = 0;
293
294 vp_dev->vqs = kcalloc(nvqs, sizeof(*vp_dev->vqs), GFP_KERNEL);
295 if (!vp_dev->vqs)
296 return -ENOMEM;
297
298 if (per_vq_vectors) {
299 /* Best option: one for change interrupt, one per vq. */
300 nvectors = 1;
301 for (i = 0; i < nvqs; ++i)
302 if (names[i] && callbacks[i])
303 ++nvectors;
304 } else {
305 /* Second best: one for change, shared for all vqs. */
306 nvectors = 2;
307 }
308
309 err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors,
310 per_vq_vectors ? desc : NULL);
311 if (err)
312 goto error_find;
313
314 vp_dev->per_vq_vectors = per_vq_vectors;
315 allocated_vectors = vp_dev->msix_used_vectors;
316 for (i = 0; i < nvqs; ++i) {
317 if (!names[i]) {
318 vqs[i] = NULL;
319 continue;
320 }
321
322 if (!callbacks[i])
323 msix_vec = VIRTIO_MSI_NO_VECTOR;
324 else if (vp_dev->per_vq_vectors)
325 msix_vec = allocated_vectors++;
326 else
327 msix_vec = VP_MSIX_VQ_VECTOR;
328 vqs[i] = vp_setup_vq(vdev, queue_idx++, callbacks[i], names[i],
329 ctx ? ctx[i] : false,
330 msix_vec);
331 if (IS_ERR(vqs[i])) {
332 err = PTR_ERR(vqs[i]);
333 goto error_find;
334 }
335
336 if (!vp_dev->per_vq_vectors || msix_vec == VIRTIO_MSI_NO_VECTOR)
337 continue;
338
339 /* allocate per-vq irq if available and necessary */
340 snprintf(vp_dev->msix_names[msix_vec],
341 sizeof *vp_dev->msix_names,
342 "%s-%s",
343 dev_name(&vp_dev->vdev.dev), names[i]);
344 err = request_irq(pci_irq_vector(vp_dev->pci_dev, msix_vec),
345 vring_interrupt, 0,
346 vp_dev->msix_names[msix_vec],
347 vqs[i]);
348 if (err)
349 goto error_find;
350 }
351 return 0;
352
353error_find:
354 vp_del_vqs(vdev);
355 return err;
356}
357
358static int vp_find_vqs_intx(struct virtio_device *vdev, unsigned int nvqs,
359 struct virtqueue *vqs[], vq_callback_t *callbacks[],
360 const char * const names[], const bool *ctx)
361{
362 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
363 int i, err, queue_idx = 0;
364
365 vp_dev->vqs = kcalloc(nvqs, sizeof(*vp_dev->vqs), GFP_KERNEL);
366 if (!vp_dev->vqs)
367 return -ENOMEM;
368
369 err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, IRQF_SHARED,
370 dev_name(&vdev->dev), vp_dev);
371 if (err)
372 goto out_del_vqs;
373
374 vp_dev->intx_enabled = 1;
375 vp_dev->per_vq_vectors = false;
376 for (i = 0; i < nvqs; ++i) {
377 if (!names[i]) {
378 vqs[i] = NULL;
379 continue;
380 }
381 vqs[i] = vp_setup_vq(vdev, queue_idx++, callbacks[i], names[i],
382 ctx ? ctx[i] : false,
383 VIRTIO_MSI_NO_VECTOR);
384 if (IS_ERR(vqs[i])) {
385 err = PTR_ERR(vqs[i]);
386 goto out_del_vqs;
387 }
388 }
389
390 return 0;
391out_del_vqs:
392 vp_del_vqs(vdev);
393 return err;
394}
395
396/* the config->find_vqs() implementation */
397int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
398 struct virtqueue *vqs[], vq_callback_t *callbacks[],
399 const char * const names[], const bool *ctx,
400 struct irq_affinity *desc)
401{
402 int err;
403
404 /* Try MSI-X with one vector per queue. */
405 err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, true, ctx, desc);
406 if (!err)
407 return 0;
408 /* Fallback: MSI-X with one vector for config, one shared for queues. */
409 err = vp_find_vqs_msix(vdev, nvqs, vqs, callbacks, names, false, ctx, desc);
410 if (!err)
411 return 0;
412 /* Is there an interrupt? If not give up. */
413 if (!(to_vp_device(vdev)->pci_dev->irq))
414 return err;
415 /* Finally fall back to regular interrupts. */
416 return vp_find_vqs_intx(vdev, nvqs, vqs, callbacks, names, ctx);
417}
418
419const char *vp_bus_name(struct virtio_device *vdev)
420{
421 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
422
423 return pci_name(vp_dev->pci_dev);
424}
425
426/* Setup the affinity for a virtqueue:
427 * - force the affinity for per vq vector
428 * - OR over all affinities for shared MSI
429 * - ignore the affinity request if we're using INTX
430 */
431int vp_set_vq_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask)
432{
433 struct virtio_device *vdev = vq->vdev;
434 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
435 struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index];
436 struct cpumask *mask;
437 unsigned int irq;
438
439 if (!vq->callback)
440 return -EINVAL;
441
442 if (vp_dev->msix_enabled) {
443 mask = vp_dev->msix_affinity_masks[info->msix_vector];
444 irq = pci_irq_vector(vp_dev->pci_dev, info->msix_vector);
445 if (!cpu_mask)
446 irq_set_affinity_hint(irq, NULL);
447 else {
448 cpumask_copy(mask, cpu_mask);
449 irq_set_affinity_hint(irq, mask);
450 }
451 }
452 return 0;
453}
454
455const struct cpumask *vp_get_vq_affinity(struct virtio_device *vdev, int index)
456{
457 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
458
459 if (!vp_dev->per_vq_vectors ||
460 vp_dev->vqs[index]->msix_vector == VIRTIO_MSI_NO_VECTOR)
461 return NULL;
462
463 return pci_irq_get_affinity(vp_dev->pci_dev,
464 vp_dev->vqs[index]->msix_vector);
465}
466
467#ifdef CONFIG_PM_SLEEP
468static int virtio_pci_freeze(struct device *dev)
469{
470 struct pci_dev *pci_dev = to_pci_dev(dev);
471 struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
472 int ret;
473
474 ret = virtio_device_freeze(&vp_dev->vdev);
475
476 if (!ret)
477 pci_disable_device(pci_dev);
478 return ret;
479}
480
481static int virtio_pci_restore(struct device *dev)
482{
483 struct pci_dev *pci_dev = to_pci_dev(dev);
484 struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
485 int ret;
486
487 ret = pci_enable_device(pci_dev);
488 if (ret)
489 return ret;
490
491 pci_set_master(pci_dev);
492 return virtio_device_restore(&vp_dev->vdev);
493}
494
495static const struct dev_pm_ops virtio_pci_pm_ops = {
496 SET_SYSTEM_SLEEP_PM_OPS(virtio_pci_freeze, virtio_pci_restore)
497};
498#endif
499
500
501/* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */
502static const struct pci_device_id virtio_pci_id_table[] = {
503 { PCI_DEVICE(PCI_VENDOR_ID_REDHAT_QUMRANET, PCI_ANY_ID) },
504 { 0 }
505};
506
507MODULE_DEVICE_TABLE(pci, virtio_pci_id_table);
508
509static void virtio_pci_release_dev(struct device *_d)
510{
511 struct virtio_device *vdev = dev_to_virtio(_d);
512 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
513
514 /* As struct device is a kobject, it's not safe to
515 * free the memory (including the reference counter itself)
516 * until it's release callback. */
517 kfree(vp_dev);
518}
519
520static int virtio_pci_probe(struct pci_dev *pci_dev,
521 const struct pci_device_id *id)
522{
523 struct virtio_pci_device *vp_dev, *reg_dev = NULL;
524 int rc;
525
526 /* allocate our structure and fill it out */
527 vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL);
528 if (!vp_dev)
529 return -ENOMEM;
530
531 pci_set_drvdata(pci_dev, vp_dev);
532 vp_dev->vdev.dev.parent = &pci_dev->dev;
533 vp_dev->vdev.dev.release = virtio_pci_release_dev;
534 vp_dev->pci_dev = pci_dev;
535 INIT_LIST_HEAD(&vp_dev->virtqueues);
536 spin_lock_init(&vp_dev->lock);
537
538 /* enable the device */
539 rc = pci_enable_device(pci_dev);
540 if (rc)
541 goto err_enable_device;
542
543 if (force_legacy) {
544 rc = virtio_pci_legacy_probe(vp_dev);
545 /* Also try modern mode if we can't map BAR0 (no IO space). */
546 if (rc == -ENODEV || rc == -ENOMEM)
547 rc = virtio_pci_modern_probe(vp_dev);
548 if (rc)
549 goto err_probe;
550 } else {
551 rc = virtio_pci_modern_probe(vp_dev);
552 if (rc == -ENODEV)
553 rc = virtio_pci_legacy_probe(vp_dev);
554 if (rc)
555 goto err_probe;
556 }
557
558 pci_set_master(pci_dev);
559
560 vp_dev->is_legacy = vp_dev->ldev.ioaddr ? true : false;
561
562 rc = register_virtio_device(&vp_dev->vdev);
563 reg_dev = vp_dev;
564 if (rc)
565 goto err_register;
566
567 return 0;
568
569err_register:
570 if (vp_dev->is_legacy)
571 virtio_pci_legacy_remove(vp_dev);
572 else
573 virtio_pci_modern_remove(vp_dev);
574err_probe:
575 pci_disable_device(pci_dev);
576err_enable_device:
577 if (reg_dev)
578 put_device(&vp_dev->vdev.dev);
579 else
580 kfree(vp_dev);
581 return rc;
582}
583
584static void virtio_pci_remove(struct pci_dev *pci_dev)
585{
586 struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
587 struct device *dev = get_device(&vp_dev->vdev.dev);
588
589 /*
590 * Device is marked broken on surprise removal so that virtio upper
591 * layers can abort any ongoing operation.
592 */
593 if (!pci_device_is_present(pci_dev))
594 virtio_break_device(&vp_dev->vdev);
595
596 pci_disable_sriov(pci_dev);
597
598 unregister_virtio_device(&vp_dev->vdev);
599
600 if (vp_dev->is_legacy)
601 virtio_pci_legacy_remove(vp_dev);
602 else
603 virtio_pci_modern_remove(vp_dev);
604
605 pci_disable_device(pci_dev);
606 put_device(dev);
607}
608
609static int virtio_pci_sriov_configure(struct pci_dev *pci_dev, int num_vfs)
610{
611 struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
612 struct virtio_device *vdev = &vp_dev->vdev;
613 int ret;
614
615 if (!(vdev->config->get_status(vdev) & VIRTIO_CONFIG_S_DRIVER_OK))
616 return -EBUSY;
617
618 if (!__virtio_test_bit(vdev, VIRTIO_F_SR_IOV))
619 return -EINVAL;
620
621 if (pci_vfs_assigned(pci_dev))
622 return -EPERM;
623
624 if (num_vfs == 0) {
625 pci_disable_sriov(pci_dev);
626 return 0;
627 }
628
629 ret = pci_enable_sriov(pci_dev, num_vfs);
630 if (ret < 0)
631 return ret;
632
633 return num_vfs;
634}
635
636static struct pci_driver virtio_pci_driver = {
637 .name = "virtio-pci",
638 .id_table = virtio_pci_id_table,
639 .probe = virtio_pci_probe,
640 .remove = virtio_pci_remove,
641#ifdef CONFIG_PM_SLEEP
642 .driver.pm = &virtio_pci_pm_ops,
643#endif
644 .sriov_configure = virtio_pci_sriov_configure,
645};
646
647module_pci_driver(virtio_pci_driver);
648
649MODULE_AUTHOR("Anthony Liguori <aliguori@us.ibm.com>");
650MODULE_DESCRIPTION("virtio-pci");
651MODULE_LICENSE("GPL");
652MODULE_VERSION("1");