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17#include <linux/module.h>
18#include <linux/list.h>
19#include <linux/pci.h>
20#include <linux/slab.h>
21#include <linux/interrupt.h>
22#include <linux/virtio.h>
23#include <linux/virtio_config.h>
24#include <linux/virtio_ring.h>
25#include <linux/virtio_pci.h>
26#include <linux/highmem.h>
27#include <linux/spinlock.h>
28
29MODULE_AUTHOR("Anthony Liguori <aliguori@us.ibm.com>");
30MODULE_DESCRIPTION("virtio-pci");
31MODULE_LICENSE("GPL");
32MODULE_VERSION("1");
33
34
35struct virtio_pci_device
36{
37 struct virtio_device vdev;
38 struct pci_dev *pci_dev;
39
40
41 void __iomem *ioaddr;
42
43
44 spinlock_t lock;
45 struct list_head virtqueues;
46
47
48 int msix_enabled;
49 int intx_enabled;
50 struct msix_entry *msix_entries;
51
52
53 char (*msix_names)[256];
54
55 unsigned msix_vectors;
56
57 unsigned msix_used_vectors;
58
59 bool per_vq_vectors;
60};
61
62
63
64
65enum {
66 VP_MSIX_CONFIG_VECTOR = 0,
67 VP_MSIX_VQ_VECTOR = 1,
68};
69
70struct virtio_pci_vq_info
71{
72
73 struct virtqueue *vq;
74
75
76 int num;
77
78
79 int queue_index;
80
81
82 void *queue;
83
84
85 struct list_head node;
86
87
88 unsigned msix_vector;
89};
90
91
92static struct pci_device_id virtio_pci_id_table[] = {
93 { 0x1af4, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
94 { 0 },
95};
96
97MODULE_DEVICE_TABLE(pci, virtio_pci_id_table);
98
99
100static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev)
101{
102 return container_of(vdev, struct virtio_pci_device, vdev);
103}
104
105
106static u32 vp_get_features(struct virtio_device *vdev)
107{
108 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
109
110
111
112 return ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES);
113}
114
115
116static void vp_finalize_features(struct virtio_device *vdev)
117{
118 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
119
120
121 vring_transport_features(vdev);
122
123
124 BUILD_BUG_ON(ARRAY_SIZE(vdev->features) != 1);
125 iowrite32(vdev->features[0], vp_dev->ioaddr+VIRTIO_PCI_GUEST_FEATURES);
126}
127
128
129static void vp_get(struct virtio_device *vdev, unsigned offset,
130 void *buf, unsigned len)
131{
132 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
133 void __iomem *ioaddr = vp_dev->ioaddr +
134 VIRTIO_PCI_CONFIG(vp_dev) + offset;
135 u8 *ptr = buf;
136 int i;
137
138 for (i = 0; i < len; i++)
139 ptr[i] = ioread8(ioaddr + i);
140}
141
142
143
144static void vp_set(struct virtio_device *vdev, unsigned offset,
145 const void *buf, unsigned len)
146{
147 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
148 void __iomem *ioaddr = vp_dev->ioaddr +
149 VIRTIO_PCI_CONFIG(vp_dev) + offset;
150 const u8 *ptr = buf;
151 int i;
152
153 for (i = 0; i < len; i++)
154 iowrite8(ptr[i], ioaddr + i);
155}
156
157
158static u8 vp_get_status(struct virtio_device *vdev)
159{
160 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
161 return ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS);
162}
163
164static void vp_set_status(struct virtio_device *vdev, u8 status)
165{
166 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
167
168 BUG_ON(status == 0);
169 iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
170}
171
172static void vp_reset(struct virtio_device *vdev)
173{
174 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
175
176 iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
177}
178
179
180static void vp_notify(struct virtqueue *vq)
181{
182 struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
183 struct virtio_pci_vq_info *info = vq->priv;
184
185
186
187 iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
188}
189
190
191static irqreturn_t vp_config_changed(int irq, void *opaque)
192{
193 struct virtio_pci_device *vp_dev = opaque;
194 struct virtio_driver *drv;
195 drv = container_of(vp_dev->vdev.dev.driver,
196 struct virtio_driver, driver);
197
198 if (drv && drv->config_changed)
199 drv->config_changed(&vp_dev->vdev);
200 return IRQ_HANDLED;
201}
202
203
204static irqreturn_t vp_vring_interrupt(int irq, void *opaque)
205{
206 struct virtio_pci_device *vp_dev = opaque;
207 struct virtio_pci_vq_info *info;
208 irqreturn_t ret = IRQ_NONE;
209 unsigned long flags;
210
211 spin_lock_irqsave(&vp_dev->lock, flags);
212 list_for_each_entry(info, &vp_dev->virtqueues, node) {
213 if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)
214 ret = IRQ_HANDLED;
215 }
216 spin_unlock_irqrestore(&vp_dev->lock, flags);
217
218 return ret;
219}
220
221
222
223
224
225
226
227static irqreturn_t vp_interrupt(int irq, void *opaque)
228{
229 struct virtio_pci_device *vp_dev = opaque;
230 u8 isr;
231
232
233
234 isr = ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);
235
236
237 if (!isr)
238 return IRQ_NONE;
239
240
241 if (isr & VIRTIO_PCI_ISR_CONFIG)
242 vp_config_changed(irq, opaque);
243
244 return vp_vring_interrupt(irq, opaque);
245}
246
247static void vp_free_vectors(struct virtio_device *vdev)
248{
249 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
250 int i;
251
252 if (vp_dev->intx_enabled) {
253 free_irq(vp_dev->pci_dev->irq, vp_dev);
254 vp_dev->intx_enabled = 0;
255 }
256
257 for (i = 0; i < vp_dev->msix_used_vectors; ++i)
258 free_irq(vp_dev->msix_entries[i].vector, vp_dev);
259
260 if (vp_dev->msix_enabled) {
261
262 iowrite16(VIRTIO_MSI_NO_VECTOR,
263 vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
264
265 ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
266
267 pci_disable_msix(vp_dev->pci_dev);
268 vp_dev->msix_enabled = 0;
269 vp_dev->msix_vectors = 0;
270 }
271
272 vp_dev->msix_used_vectors = 0;
273 kfree(vp_dev->msix_names);
274 vp_dev->msix_names = NULL;
275 kfree(vp_dev->msix_entries);
276 vp_dev->msix_entries = NULL;
277}
278
279static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors,
280 bool per_vq_vectors)
281{
282 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
283 const char *name = dev_name(&vp_dev->vdev.dev);
284 unsigned i, v;
285 int err = -ENOMEM;
286
287 vp_dev->msix_entries = kmalloc(nvectors * sizeof *vp_dev->msix_entries,
288 GFP_KERNEL);
289 if (!vp_dev->msix_entries)
290 goto error;
291 vp_dev->msix_names = kmalloc(nvectors * sizeof *vp_dev->msix_names,
292 GFP_KERNEL);
293 if (!vp_dev->msix_names)
294 goto error;
295
296 for (i = 0; i < nvectors; ++i)
297 vp_dev->msix_entries[i].entry = i;
298
299
300 err = pci_enable_msix(vp_dev->pci_dev, vp_dev->msix_entries, nvectors);
301 if (err > 0)
302 err = -ENOSPC;
303 if (err)
304 goto error;
305 vp_dev->msix_vectors = nvectors;
306 vp_dev->msix_enabled = 1;
307
308
309 v = vp_dev->msix_used_vectors;
310 snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
311 "%s-config", name);
312 err = request_irq(vp_dev->msix_entries[v].vector,
313 vp_config_changed, 0, vp_dev->msix_names[v],
314 vp_dev);
315 if (err)
316 goto error;
317 ++vp_dev->msix_used_vectors;
318
319 iowrite16(v, vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
320
321 v = ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
322 if (v == VIRTIO_MSI_NO_VECTOR) {
323 err = -EBUSY;
324 goto error;
325 }
326
327 if (!per_vq_vectors) {
328
329 v = vp_dev->msix_used_vectors;
330 snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
331 "%s-virtqueues", name);
332 err = request_irq(vp_dev->msix_entries[v].vector,
333 vp_vring_interrupt, 0, vp_dev->msix_names[v],
334 vp_dev);
335 if (err)
336 goto error;
337 ++vp_dev->msix_used_vectors;
338 }
339 return 0;
340error:
341 vp_free_vectors(vdev);
342 return err;
343}
344
345static int vp_request_intx(struct virtio_device *vdev)
346{
347 int err;
348 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
349
350 err = request_irq(vp_dev->pci_dev->irq, vp_interrupt,
351 IRQF_SHARED, dev_name(&vdev->dev), vp_dev);
352 if (!err)
353 vp_dev->intx_enabled = 1;
354 return err;
355}
356
357static struct virtqueue *setup_vq(struct virtio_device *vdev, unsigned index,
358 void (*callback)(struct virtqueue *vq),
359 const char *name,
360 u16 msix_vec)
361{
362 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
363 struct virtio_pci_vq_info *info;
364 struct virtqueue *vq;
365 unsigned long flags, size;
366 u16 num;
367 int err;
368
369
370 iowrite16(index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
371
372
373 num = ioread16(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NUM);
374 if (!num || ioread32(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN))
375 return ERR_PTR(-ENOENT);
376
377
378
379 info = kmalloc(sizeof(struct virtio_pci_vq_info), GFP_KERNEL);
380 if (!info)
381 return ERR_PTR(-ENOMEM);
382
383 info->queue_index = index;
384 info->num = num;
385 info->msix_vector = msix_vec;
386
387 size = PAGE_ALIGN(vring_size(num, VIRTIO_PCI_VRING_ALIGN));
388 info->queue = alloc_pages_exact(size, GFP_KERNEL|__GFP_ZERO);
389 if (info->queue == NULL) {
390 err = -ENOMEM;
391 goto out_info;
392 }
393
394
395 iowrite32(virt_to_phys(info->queue) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT,
396 vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
397
398
399 vq = vring_new_virtqueue(info->num, VIRTIO_PCI_VRING_ALIGN,
400 vdev, info->queue, vp_notify, callback, name);
401 if (!vq) {
402 err = -ENOMEM;
403 goto out_activate_queue;
404 }
405
406 vq->priv = info;
407 info->vq = vq;
408
409 if (msix_vec != VIRTIO_MSI_NO_VECTOR) {
410 iowrite16(msix_vec, vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
411 msix_vec = ioread16(vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
412 if (msix_vec == VIRTIO_MSI_NO_VECTOR) {
413 err = -EBUSY;
414 goto out_assign;
415 }
416 }
417
418 spin_lock_irqsave(&vp_dev->lock, flags);
419 list_add(&info->node, &vp_dev->virtqueues);
420 spin_unlock_irqrestore(&vp_dev->lock, flags);
421
422 return vq;
423
424out_assign:
425 vring_del_virtqueue(vq);
426out_activate_queue:
427 iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
428 free_pages_exact(info->queue, size);
429out_info:
430 kfree(info);
431 return ERR_PTR(err);
432}
433
434static void vp_del_vq(struct virtqueue *vq)
435{
436 struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
437 struct virtio_pci_vq_info *info = vq->priv;
438 unsigned long flags, size;
439
440 spin_lock_irqsave(&vp_dev->lock, flags);
441 list_del(&info->node);
442 spin_unlock_irqrestore(&vp_dev->lock, flags);
443
444 iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
445
446 if (vp_dev->msix_enabled) {
447 iowrite16(VIRTIO_MSI_NO_VECTOR,
448 vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
449
450 ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);
451 }
452
453 vring_del_virtqueue(vq);
454
455
456 iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
457
458 size = PAGE_ALIGN(vring_size(info->num, VIRTIO_PCI_VRING_ALIGN));
459 free_pages_exact(info->queue, size);
460 kfree(info);
461}
462
463
464static void vp_del_vqs(struct virtio_device *vdev)
465{
466 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
467 struct virtqueue *vq, *n;
468 struct virtio_pci_vq_info *info;
469
470 list_for_each_entry_safe(vq, n, &vdev->vqs, list) {
471 info = vq->priv;
472 if (vp_dev->per_vq_vectors &&
473 info->msix_vector != VIRTIO_MSI_NO_VECTOR)
474 free_irq(vp_dev->msix_entries[info->msix_vector].vector,
475 vq);
476 vp_del_vq(vq);
477 }
478 vp_dev->per_vq_vectors = false;
479
480 vp_free_vectors(vdev);
481}
482
483static int vp_try_to_find_vqs(struct virtio_device *vdev, unsigned nvqs,
484 struct virtqueue *vqs[],
485 vq_callback_t *callbacks[],
486 const char *names[],
487 bool use_msix,
488 bool per_vq_vectors)
489{
490 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
491 u16 msix_vec;
492 int i, err, nvectors, allocated_vectors;
493
494 if (!use_msix) {
495
496 err = vp_request_intx(vdev);
497 if (err)
498 goto error_request;
499 } else {
500 if (per_vq_vectors) {
501
502 nvectors = 1;
503 for (i = 0; i < nvqs; ++i)
504 if (callbacks[i])
505 ++nvectors;
506 } else {
507
508 nvectors = 2;
509 }
510
511 err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors);
512 if (err)
513 goto error_request;
514 }
515
516 vp_dev->per_vq_vectors = per_vq_vectors;
517 allocated_vectors = vp_dev->msix_used_vectors;
518 for (i = 0; i < nvqs; ++i) {
519 if (!callbacks[i] || !vp_dev->msix_enabled)
520 msix_vec = VIRTIO_MSI_NO_VECTOR;
521 else if (vp_dev->per_vq_vectors)
522 msix_vec = allocated_vectors++;
523 else
524 msix_vec = VP_MSIX_VQ_VECTOR;
525 vqs[i] = setup_vq(vdev, i, callbacks[i], names[i], msix_vec);
526 if (IS_ERR(vqs[i])) {
527 err = PTR_ERR(vqs[i]);
528 goto error_find;
529 }
530
531 if (!vp_dev->per_vq_vectors || msix_vec == VIRTIO_MSI_NO_VECTOR)
532 continue;
533
534
535 snprintf(vp_dev->msix_names[msix_vec],
536 sizeof *vp_dev->msix_names,
537 "%s-%s",
538 dev_name(&vp_dev->vdev.dev), names[i]);
539 err = request_irq(vp_dev->msix_entries[msix_vec].vector,
540 vring_interrupt, 0,
541 vp_dev->msix_names[msix_vec],
542 vqs[i]);
543 if (err) {
544 vp_del_vq(vqs[i]);
545 goto error_find;
546 }
547 }
548 return 0;
549
550error_find:
551 vp_del_vqs(vdev);
552
553error_request:
554 return err;
555}
556
557
558static int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
559 struct virtqueue *vqs[],
560 vq_callback_t *callbacks[],
561 const char *names[])
562{
563 int err;
564
565
566 err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, true, true);
567 if (!err)
568 return 0;
569
570 err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names,
571 true, false);
572 if (!err)
573 return 0;
574
575 return vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names,
576 false, false);
577}
578
579static struct virtio_config_ops virtio_pci_config_ops = {
580 .get = vp_get,
581 .set = vp_set,
582 .get_status = vp_get_status,
583 .set_status = vp_set_status,
584 .reset = vp_reset,
585 .find_vqs = vp_find_vqs,
586 .del_vqs = vp_del_vqs,
587 .get_features = vp_get_features,
588 .finalize_features = vp_finalize_features,
589};
590
591static void virtio_pci_release_dev(struct device *_d)
592{
593 struct virtio_device *dev = container_of(_d, struct virtio_device, dev);
594 struct virtio_pci_device *vp_dev = to_vp_device(dev);
595 struct pci_dev *pci_dev = vp_dev->pci_dev;
596
597 vp_del_vqs(dev);
598 pci_set_drvdata(pci_dev, NULL);
599 pci_iounmap(pci_dev, vp_dev->ioaddr);
600 pci_release_regions(pci_dev);
601 pci_disable_device(pci_dev);
602 kfree(vp_dev);
603}
604
605
606static int __devinit virtio_pci_probe(struct pci_dev *pci_dev,
607 const struct pci_device_id *id)
608{
609 struct virtio_pci_device *vp_dev;
610 int err;
611
612
613 if (pci_dev->device < 0x1000 || pci_dev->device > 0x103f)
614 return -ENODEV;
615
616 if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION) {
617 printk(KERN_ERR "virtio_pci: expected ABI version %d, got %d\n",
618 VIRTIO_PCI_ABI_VERSION, pci_dev->revision);
619 return -ENODEV;
620 }
621
622
623 vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL);
624 if (vp_dev == NULL)
625 return -ENOMEM;
626
627 vp_dev->vdev.dev.parent = &pci_dev->dev;
628 vp_dev->vdev.dev.release = virtio_pci_release_dev;
629 vp_dev->vdev.config = &virtio_pci_config_ops;
630 vp_dev->pci_dev = pci_dev;
631 INIT_LIST_HEAD(&vp_dev->virtqueues);
632 spin_lock_init(&vp_dev->lock);
633
634
635 pci_msi_off(pci_dev);
636
637
638 err = pci_enable_device(pci_dev);
639 if (err)
640 goto out;
641
642 err = pci_request_regions(pci_dev, "virtio-pci");
643 if (err)
644 goto out_enable_device;
645
646 vp_dev->ioaddr = pci_iomap(pci_dev, 0, 0);
647 if (vp_dev->ioaddr == NULL)
648 goto out_req_regions;
649
650 pci_set_drvdata(pci_dev, vp_dev);
651 pci_set_master(pci_dev);
652
653
654
655
656
657 vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
658 vp_dev->vdev.id.device = pci_dev->subsystem_device;
659
660
661 err = register_virtio_device(&vp_dev->vdev);
662 if (err)
663 goto out_set_drvdata;
664
665 return 0;
666
667out_set_drvdata:
668 pci_set_drvdata(pci_dev, NULL);
669 pci_iounmap(pci_dev, vp_dev->ioaddr);
670out_req_regions:
671 pci_release_regions(pci_dev);
672out_enable_device:
673 pci_disable_device(pci_dev);
674out:
675 kfree(vp_dev);
676 return err;
677}
678
679static void __devexit virtio_pci_remove(struct pci_dev *pci_dev)
680{
681 struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
682
683 unregister_virtio_device(&vp_dev->vdev);
684}
685
686#ifdef CONFIG_PM
687static int virtio_pci_suspend(struct pci_dev *pci_dev, pm_message_t state)
688{
689 pci_save_state(pci_dev);
690 pci_set_power_state(pci_dev, PCI_D3hot);
691 return 0;
692}
693
694static int virtio_pci_resume(struct pci_dev *pci_dev)
695{
696 pci_restore_state(pci_dev);
697 pci_set_power_state(pci_dev, PCI_D0);
698 return 0;
699}
700#endif
701
702static struct pci_driver virtio_pci_driver = {
703 .name = "virtio-pci",
704 .id_table = virtio_pci_id_table,
705 .probe = virtio_pci_probe,
706 .remove = __devexit_p(virtio_pci_remove),
707#ifdef CONFIG_PM
708 .suspend = virtio_pci_suspend,
709 .resume = virtio_pci_resume,
710#endif
711};
712
713static int __init virtio_pci_init(void)
714{
715 return pci_register_driver(&virtio_pci_driver);
716}
717
718module_init(virtio_pci_init);
719
720static void __exit virtio_pci_exit(void)
721{
722 pci_unregister_driver(&virtio_pci_driver);
723}
724
725module_exit(virtio_pci_exit);
726