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1/*
2 * Virtio PCI driver
3 *
4 * This module allows virtio devices to be used over a virtual PCI device.
5 * This can be used with QEMU based VMMs like KVM or Xen.
6 *
7 * Copyright IBM Corp. 2007
8 *
9 * Authors:
10 * Anthony Liguori <aliguori@us.ibm.com>
11 *
12 * This work is licensed under the terms of the GNU GPL, version 2 or later.
13 * See the COPYING file in the top-level directory.
14 *
15 */
16
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/* Our device structure */
35struct virtio_pci_device
36{
37 struct virtio_device vdev;
38 struct pci_dev *pci_dev;
39
40 /* the IO mapping for the PCI config space */
41 void __iomem *ioaddr;
42
43 /* a list of queues so we can dispatch IRQs */
44 spinlock_t lock;
45 struct list_head virtqueues;
46
47 /* MSI-X support */
48 int msix_enabled;
49 int intx_enabled;
50 struct msix_entry *msix_entries;
51 /* Name strings for interrupts. This size should be enough,
52 * and I'm too lazy to allocate each name separately. */
53 char (*msix_names)[256];
54 /* Number of available vectors */
55 unsigned msix_vectors;
56 /* Vectors allocated, excluding per-vq vectors if any */
57 unsigned msix_used_vectors;
58 /* Whether we have vector per vq */
59 bool per_vq_vectors;
60};
61
62/* Constants for MSI-X */
63/* Use first vector for configuration changes, second and the rest for
64 * virtqueues Thus, we need at least 2 vectors for MSI. */
65enum {
66 VP_MSIX_CONFIG_VECTOR = 0,
67 VP_MSIX_VQ_VECTOR = 1,
68};
69
70struct virtio_pci_vq_info
71{
72 /* the actual virtqueue */
73 struct virtqueue *vq;
74
75 /* the number of entries in the queue */
76 int num;
77
78 /* the index of the queue */
79 int queue_index;
80
81 /* the virtual address of the ring queue */
82 void *queue;
83
84 /* the list node for the virtqueues list */
85 struct list_head node;
86
87 /* MSI-X vector (or none) */
88 unsigned msix_vector;
89};
90
91/* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */
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/* Convert a generic virtio device to our structure */
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/* virtio config->get_features() implementation */
106static u32 vp_get_features(struct virtio_device *vdev)
107{
108 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
109
110 /* When someone needs more than 32 feature bits, we'll need to
111 * steal a bit to indicate that the rest are somewhere else. */
112 return ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES);
113}
114
115/* virtio config->finalize_features() implementation */
116static void vp_finalize_features(struct virtio_device *vdev)
117{
118 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
119
120 /* Give virtio_ring a chance to accept features. */
121 vring_transport_features(vdev);
122
123 /* We only support 32 feature bits. */
124 BUILD_BUG_ON(ARRAY_SIZE(vdev->features) != 1);
125 iowrite32(vdev->features[0], vp_dev->ioaddr+VIRTIO_PCI_GUEST_FEATURES);
126}
127
128/* virtio config->get() implementation */
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/* the config->set() implementation. it's symmetric to the config->get()
143 * implementation */
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/* config->{get,set}_status() implementations */
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 /* We should never be setting status to 0. */
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 /* 0 status means a reset. */
176 iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
177}
178
179/* the notify function used when creating a virt queue */
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 /* we write the queue's selector into the notification register to
186 * signal the other end */
187 iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
188}
189
190/* Handle a configuration change: Tell driver if it wants to know. */
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/* Notify all virtqueues on an interrupt. */
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/* A small wrapper to also acknowledge the interrupt when it's handled.
222 * I really need an EIO hook for the vring so I can ack the interrupt once we
223 * know that we'll be handling the IRQ but before we invoke the callback since
224 * the callback may notify the host which results in the host attempting to
225 * raise an interrupt that we would then mask once we acknowledged the
226 * interrupt. */
227static irqreturn_t vp_interrupt(int irq, void *opaque)
228{
229 struct virtio_pci_device *vp_dev = opaque;
230 u8 isr;
231
232 /* reading the ISR has the effect of also clearing it so it's very
233 * important to save off the value. */
234 isr = ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);
235
236 /* It's definitely not us if the ISR was not high */
237 if (!isr)
238 return IRQ_NONE;
239
240 /* Configuration change? Tell driver if it wants to know. */
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 /* Disable the vector used for configuration */
262 iowrite16(VIRTIO_MSI_NO_VECTOR,
263 vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
264 /* Flush the write out to device */
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 /* pci_enable_msix returns positive if we can't get this many. */
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 /* Set the vector used for configuration */
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 /* Verify we had enough resources to assign the vector */
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 /* Shared vector for all VQs */
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 /* Select the queue we're interested in */
370 iowrite16(index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
371
372 /* Check if queue is either not available or already active. */
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 /* allocate and fill out our structure the represents an active
378 * queue */
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 /* activate the queue */
395 iowrite32(virt_to_phys(info->queue) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT,
396 vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
397
398 /* create the vring */
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 /* Flush the write out to device */
450 ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);
451 }
452
453 vring_del_virtqueue(vq);
454
455 /* Select and deactivate the queue */
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/* the config->del_vqs() implementation */
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 /* Old style: one normal interrupt for change and all vqs. */
496 err = vp_request_intx(vdev);
497 if (err)
498 goto error_request;
499 } else {
500 if (per_vq_vectors) {
501 /* Best option: one for change interrupt, one per vq. */
502 nvectors = 1;
503 for (i = 0; i < nvqs; ++i)
504 if (callbacks[i])
505 ++nvectors;
506 } else {
507 /* Second best: one for change, shared for all vqs. */
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 /* allocate per-vq irq if available and necessary */
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/* the config->find_vqs() implementation */
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 /* Try MSI-X with one vector per queue. */
566 err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, true, true);
567 if (!err)
568 return 0;
569 /* Fallback: MSI-X with one vector for config, one shared for queues. */
570 err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names,
571 true, false);
572 if (!err)
573 return 0;
574 /* Finally fall back to regular interrupts. */
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,
594 dev);
595 struct virtio_pci_device *vp_dev = to_vp_device(dev);
596
597 kfree(vp_dev);
598}
599
600/* the PCI probing function */
601static int __devinit virtio_pci_probe(struct pci_dev *pci_dev,
602 const struct pci_device_id *id)
603{
604 struct virtio_pci_device *vp_dev;
605 int err;
606
607 /* We only own devices >= 0x1000 and <= 0x103f: leave the rest. */
608 if (pci_dev->device < 0x1000 || pci_dev->device > 0x103f)
609 return -ENODEV;
610
611 if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION) {
612 printk(KERN_ERR "virtio_pci: expected ABI version %d, got %d\n",
613 VIRTIO_PCI_ABI_VERSION, pci_dev->revision);
614 return -ENODEV;
615 }
616
617 /* allocate our structure and fill it out */
618 vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL);
619 if (vp_dev == NULL)
620 return -ENOMEM;
621
622 vp_dev->vdev.dev.parent = &pci_dev->dev;
623 vp_dev->vdev.dev.release = virtio_pci_release_dev;
624 vp_dev->vdev.config = &virtio_pci_config_ops;
625 vp_dev->pci_dev = pci_dev;
626 INIT_LIST_HEAD(&vp_dev->virtqueues);
627 spin_lock_init(&vp_dev->lock);
628
629 /* Disable MSI/MSIX to bring device to a known good state. */
630 pci_msi_off(pci_dev);
631
632 /* enable the device */
633 err = pci_enable_device(pci_dev);
634 if (err)
635 goto out;
636
637 err = pci_request_regions(pci_dev, "virtio-pci");
638 if (err)
639 goto out_enable_device;
640
641 vp_dev->ioaddr = pci_iomap(pci_dev, 0, 0);
642 if (vp_dev->ioaddr == NULL)
643 goto out_req_regions;
644
645 pci_set_drvdata(pci_dev, vp_dev);
646 pci_set_master(pci_dev);
647
648 /* we use the subsystem vendor/device id as the virtio vendor/device
649 * id. this allows us to use the same PCI vendor/device id for all
650 * virtio devices and to identify the particular virtio driver by
651 * the subsystem ids */
652 vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
653 vp_dev->vdev.id.device = pci_dev->subsystem_device;
654
655 /* finally register the virtio device */
656 err = register_virtio_device(&vp_dev->vdev);
657 if (err)
658 goto out_set_drvdata;
659
660 return 0;
661
662out_set_drvdata:
663 pci_set_drvdata(pci_dev, NULL);
664 pci_iounmap(pci_dev, vp_dev->ioaddr);
665out_req_regions:
666 pci_release_regions(pci_dev);
667out_enable_device:
668 pci_disable_device(pci_dev);
669out:
670 kfree(vp_dev);
671 return err;
672}
673
674static void __devexit virtio_pci_remove(struct pci_dev *pci_dev)
675{
676 struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
677
678 unregister_virtio_device(&vp_dev->vdev);
679
680 vp_del_vqs(&vp_dev->vdev);
681 pci_set_drvdata(pci_dev, NULL);
682 pci_iounmap(pci_dev, vp_dev->ioaddr);
683 pci_release_regions(pci_dev);
684 pci_disable_device(pci_dev);
685}
686
687#ifdef CONFIG_PM
688static int virtio_pci_suspend(struct pci_dev *pci_dev, pm_message_t state)
689{
690 pci_save_state(pci_dev);
691 pci_set_power_state(pci_dev, PCI_D3hot);
692 return 0;
693}
694
695static int virtio_pci_resume(struct pci_dev *pci_dev)
696{
697 pci_restore_state(pci_dev);
698 pci_set_power_state(pci_dev, PCI_D0);
699 return 0;
700}
701#endif
702
703static struct pci_driver virtio_pci_driver = {
704 .name = "virtio-pci",
705 .id_table = virtio_pci_id_table,
706 .probe = virtio_pci_probe,
707 .remove = __devexit_p(virtio_pci_remove),
708#ifdef CONFIG_PM
709 .suspend = virtio_pci_suspend,
710 .resume = virtio_pci_resume,
711#endif
712};
713
714static int __init virtio_pci_init(void)
715{
716 return pci_register_driver(&virtio_pci_driver);
717}
718
719module_init(virtio_pci_init);
720
721static void __exit virtio_pci_exit(void)
722{
723 pci_unregister_driver(&virtio_pci_driver);
724}
725
726module_exit(virtio_pci_exit);
1/*
2 * Virtio PCI driver
3 *
4 * This module allows virtio devices to be used over a virtual PCI device.
5 * This can be used with QEMU based VMMs like KVM or Xen.
6 *
7 * Copyright IBM Corp. 2007
8 *
9 * Authors:
10 * Anthony Liguori <aliguori@us.ibm.com>
11 *
12 * This work is licensed under the terms of the GNU GPL, version 2 or later.
13 * See the COPYING file in the top-level directory.
14 *
15 */
16
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/* Our device structure */
35struct virtio_pci_device
36{
37 struct virtio_device vdev;
38 struct pci_dev *pci_dev;
39
40 /* the IO mapping for the PCI config space */
41 void __iomem *ioaddr;
42
43 /* a list of queues so we can dispatch IRQs */
44 spinlock_t lock;
45 struct list_head virtqueues;
46
47 /* MSI-X support */
48 int msix_enabled;
49 int intx_enabled;
50 struct msix_entry *msix_entries;
51 /* Name strings for interrupts. This size should be enough,
52 * and I'm too lazy to allocate each name separately. */
53 char (*msix_names)[256];
54 /* Number of available vectors */
55 unsigned msix_vectors;
56 /* Vectors allocated, excluding per-vq vectors if any */
57 unsigned msix_used_vectors;
58
59 /* Status saved during hibernate/restore */
60 u8 saved_status;
61
62 /* Whether we have vector per vq */
63 bool per_vq_vectors;
64};
65
66/* Constants for MSI-X */
67/* Use first vector for configuration changes, second and the rest for
68 * virtqueues Thus, we need at least 2 vectors for MSI. */
69enum {
70 VP_MSIX_CONFIG_VECTOR = 0,
71 VP_MSIX_VQ_VECTOR = 1,
72};
73
74struct virtio_pci_vq_info
75{
76 /* the actual virtqueue */
77 struct virtqueue *vq;
78
79 /* the number of entries in the queue */
80 int num;
81
82 /* the index of the queue */
83 int queue_index;
84
85 /* the virtual address of the ring queue */
86 void *queue;
87
88 /* the list node for the virtqueues list */
89 struct list_head node;
90
91 /* MSI-X vector (or none) */
92 unsigned msix_vector;
93};
94
95/* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */
96static struct pci_device_id virtio_pci_id_table[] = {
97 { 0x1af4, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
98 { 0 },
99};
100
101MODULE_DEVICE_TABLE(pci, virtio_pci_id_table);
102
103/* Convert a generic virtio device to our structure */
104static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev)
105{
106 return container_of(vdev, struct virtio_pci_device, vdev);
107}
108
109/* virtio config->get_features() implementation */
110static u32 vp_get_features(struct virtio_device *vdev)
111{
112 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
113
114 /* When someone needs more than 32 feature bits, we'll need to
115 * steal a bit to indicate that the rest are somewhere else. */
116 return ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES);
117}
118
119/* virtio config->finalize_features() implementation */
120static void vp_finalize_features(struct virtio_device *vdev)
121{
122 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
123
124 /* Give virtio_ring a chance to accept features. */
125 vring_transport_features(vdev);
126
127 /* We only support 32 feature bits. */
128 BUILD_BUG_ON(ARRAY_SIZE(vdev->features) != 1);
129 iowrite32(vdev->features[0], vp_dev->ioaddr+VIRTIO_PCI_GUEST_FEATURES);
130}
131
132/* virtio config->get() implementation */
133static void vp_get(struct virtio_device *vdev, unsigned offset,
134 void *buf, unsigned len)
135{
136 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
137 void __iomem *ioaddr = vp_dev->ioaddr +
138 VIRTIO_PCI_CONFIG(vp_dev) + offset;
139 u8 *ptr = buf;
140 int i;
141
142 for (i = 0; i < len; i++)
143 ptr[i] = ioread8(ioaddr + i);
144}
145
146/* the config->set() implementation. it's symmetric to the config->get()
147 * implementation */
148static void vp_set(struct virtio_device *vdev, unsigned offset,
149 const void *buf, unsigned len)
150{
151 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
152 void __iomem *ioaddr = vp_dev->ioaddr +
153 VIRTIO_PCI_CONFIG(vp_dev) + offset;
154 const u8 *ptr = buf;
155 int i;
156
157 for (i = 0; i < len; i++)
158 iowrite8(ptr[i], ioaddr + i);
159}
160
161/* config->{get,set}_status() implementations */
162static u8 vp_get_status(struct virtio_device *vdev)
163{
164 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
165 return ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS);
166}
167
168static void vp_set_status(struct virtio_device *vdev, u8 status)
169{
170 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
171 /* We should never be setting status to 0. */
172 BUG_ON(status == 0);
173 iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
174}
175
176/* wait for pending irq handlers */
177static void vp_synchronize_vectors(struct virtio_device *vdev)
178{
179 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
180 int i;
181
182 if (vp_dev->intx_enabled)
183 synchronize_irq(vp_dev->pci_dev->irq);
184
185 for (i = 0; i < vp_dev->msix_vectors; ++i)
186 synchronize_irq(vp_dev->msix_entries[i].vector);
187}
188
189static void vp_reset(struct virtio_device *vdev)
190{
191 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
192 /* 0 status means a reset. */
193 iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
194 /* Flush out the status write, and flush in device writes,
195 * including MSi-X interrupts, if any. */
196 ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS);
197 /* Flush pending VQ/configuration callbacks. */
198 vp_synchronize_vectors(vdev);
199}
200
201/* the notify function used when creating a virt queue */
202static void vp_notify(struct virtqueue *vq)
203{
204 struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
205 struct virtio_pci_vq_info *info = vq->priv;
206
207 /* we write the queue's selector into the notification register to
208 * signal the other end */
209 iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
210}
211
212/* Handle a configuration change: Tell driver if it wants to know. */
213static irqreturn_t vp_config_changed(int irq, void *opaque)
214{
215 struct virtio_pci_device *vp_dev = opaque;
216 struct virtio_driver *drv;
217 drv = container_of(vp_dev->vdev.dev.driver,
218 struct virtio_driver, driver);
219
220 if (drv && drv->config_changed)
221 drv->config_changed(&vp_dev->vdev);
222 return IRQ_HANDLED;
223}
224
225/* Notify all virtqueues on an interrupt. */
226static irqreturn_t vp_vring_interrupt(int irq, void *opaque)
227{
228 struct virtio_pci_device *vp_dev = opaque;
229 struct virtio_pci_vq_info *info;
230 irqreturn_t ret = IRQ_NONE;
231 unsigned long flags;
232
233 spin_lock_irqsave(&vp_dev->lock, flags);
234 list_for_each_entry(info, &vp_dev->virtqueues, node) {
235 if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)
236 ret = IRQ_HANDLED;
237 }
238 spin_unlock_irqrestore(&vp_dev->lock, flags);
239
240 return ret;
241}
242
243/* A small wrapper to also acknowledge the interrupt when it's handled.
244 * I really need an EIO hook for the vring so I can ack the interrupt once we
245 * know that we'll be handling the IRQ but before we invoke the callback since
246 * the callback may notify the host which results in the host attempting to
247 * raise an interrupt that we would then mask once we acknowledged the
248 * interrupt. */
249static irqreturn_t vp_interrupt(int irq, void *opaque)
250{
251 struct virtio_pci_device *vp_dev = opaque;
252 u8 isr;
253
254 /* reading the ISR has the effect of also clearing it so it's very
255 * important to save off the value. */
256 isr = ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);
257
258 /* It's definitely not us if the ISR was not high */
259 if (!isr)
260 return IRQ_NONE;
261
262 /* Configuration change? Tell driver if it wants to know. */
263 if (isr & VIRTIO_PCI_ISR_CONFIG)
264 vp_config_changed(irq, opaque);
265
266 return vp_vring_interrupt(irq, opaque);
267}
268
269static void vp_free_vectors(struct virtio_device *vdev)
270{
271 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
272 int i;
273
274 if (vp_dev->intx_enabled) {
275 free_irq(vp_dev->pci_dev->irq, vp_dev);
276 vp_dev->intx_enabled = 0;
277 }
278
279 for (i = 0; i < vp_dev->msix_used_vectors; ++i)
280 free_irq(vp_dev->msix_entries[i].vector, vp_dev);
281
282 if (vp_dev->msix_enabled) {
283 /* Disable the vector used for configuration */
284 iowrite16(VIRTIO_MSI_NO_VECTOR,
285 vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
286 /* Flush the write out to device */
287 ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
288
289 pci_disable_msix(vp_dev->pci_dev);
290 vp_dev->msix_enabled = 0;
291 vp_dev->msix_vectors = 0;
292 }
293
294 vp_dev->msix_used_vectors = 0;
295 kfree(vp_dev->msix_names);
296 vp_dev->msix_names = NULL;
297 kfree(vp_dev->msix_entries);
298 vp_dev->msix_entries = NULL;
299}
300
301static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors,
302 bool per_vq_vectors)
303{
304 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
305 const char *name = dev_name(&vp_dev->vdev.dev);
306 unsigned i, v;
307 int err = -ENOMEM;
308
309 vp_dev->msix_entries = kmalloc(nvectors * sizeof *vp_dev->msix_entries,
310 GFP_KERNEL);
311 if (!vp_dev->msix_entries)
312 goto error;
313 vp_dev->msix_names = kmalloc(nvectors * sizeof *vp_dev->msix_names,
314 GFP_KERNEL);
315 if (!vp_dev->msix_names)
316 goto error;
317
318 for (i = 0; i < nvectors; ++i)
319 vp_dev->msix_entries[i].entry = i;
320
321 /* pci_enable_msix returns positive if we can't get this many. */
322 err = pci_enable_msix(vp_dev->pci_dev, vp_dev->msix_entries, nvectors);
323 if (err > 0)
324 err = -ENOSPC;
325 if (err)
326 goto error;
327 vp_dev->msix_vectors = nvectors;
328 vp_dev->msix_enabled = 1;
329
330 /* Set the vector used for configuration */
331 v = vp_dev->msix_used_vectors;
332 snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
333 "%s-config", name);
334 err = request_irq(vp_dev->msix_entries[v].vector,
335 vp_config_changed, 0, vp_dev->msix_names[v],
336 vp_dev);
337 if (err)
338 goto error;
339 ++vp_dev->msix_used_vectors;
340
341 iowrite16(v, vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
342 /* Verify we had enough resources to assign the vector */
343 v = ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
344 if (v == VIRTIO_MSI_NO_VECTOR) {
345 err = -EBUSY;
346 goto error;
347 }
348
349 if (!per_vq_vectors) {
350 /* Shared vector for all VQs */
351 v = vp_dev->msix_used_vectors;
352 snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
353 "%s-virtqueues", name);
354 err = request_irq(vp_dev->msix_entries[v].vector,
355 vp_vring_interrupt, 0, vp_dev->msix_names[v],
356 vp_dev);
357 if (err)
358 goto error;
359 ++vp_dev->msix_used_vectors;
360 }
361 return 0;
362error:
363 vp_free_vectors(vdev);
364 return err;
365}
366
367static int vp_request_intx(struct virtio_device *vdev)
368{
369 int err;
370 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
371
372 err = request_irq(vp_dev->pci_dev->irq, vp_interrupt,
373 IRQF_SHARED, dev_name(&vdev->dev), vp_dev);
374 if (!err)
375 vp_dev->intx_enabled = 1;
376 return err;
377}
378
379static struct virtqueue *setup_vq(struct virtio_device *vdev, unsigned index,
380 void (*callback)(struct virtqueue *vq),
381 const char *name,
382 u16 msix_vec)
383{
384 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
385 struct virtio_pci_vq_info *info;
386 struct virtqueue *vq;
387 unsigned long flags, size;
388 u16 num;
389 int err;
390
391 /* Select the queue we're interested in */
392 iowrite16(index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
393
394 /* Check if queue is either not available or already active. */
395 num = ioread16(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NUM);
396 if (!num || ioread32(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN))
397 return ERR_PTR(-ENOENT);
398
399 /* allocate and fill out our structure the represents an active
400 * queue */
401 info = kmalloc(sizeof(struct virtio_pci_vq_info), GFP_KERNEL);
402 if (!info)
403 return ERR_PTR(-ENOMEM);
404
405 info->queue_index = index;
406 info->num = num;
407 info->msix_vector = msix_vec;
408
409 size = PAGE_ALIGN(vring_size(num, VIRTIO_PCI_VRING_ALIGN));
410 info->queue = alloc_pages_exact(size, GFP_KERNEL|__GFP_ZERO);
411 if (info->queue == NULL) {
412 err = -ENOMEM;
413 goto out_info;
414 }
415
416 /* activate the queue */
417 iowrite32(virt_to_phys(info->queue) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT,
418 vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
419
420 /* create the vring */
421 vq = vring_new_virtqueue(info->num, VIRTIO_PCI_VRING_ALIGN, vdev,
422 true, info->queue, vp_notify, callback, name);
423 if (!vq) {
424 err = -ENOMEM;
425 goto out_activate_queue;
426 }
427
428 vq->priv = info;
429 info->vq = vq;
430
431 if (msix_vec != VIRTIO_MSI_NO_VECTOR) {
432 iowrite16(msix_vec, vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
433 msix_vec = ioread16(vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
434 if (msix_vec == VIRTIO_MSI_NO_VECTOR) {
435 err = -EBUSY;
436 goto out_assign;
437 }
438 }
439
440 if (callback) {
441 spin_lock_irqsave(&vp_dev->lock, flags);
442 list_add(&info->node, &vp_dev->virtqueues);
443 spin_unlock_irqrestore(&vp_dev->lock, flags);
444 } else {
445 INIT_LIST_HEAD(&info->node);
446 }
447
448 return vq;
449
450out_assign:
451 vring_del_virtqueue(vq);
452out_activate_queue:
453 iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
454 free_pages_exact(info->queue, size);
455out_info:
456 kfree(info);
457 return ERR_PTR(err);
458}
459
460static void vp_del_vq(struct virtqueue *vq)
461{
462 struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
463 struct virtio_pci_vq_info *info = vq->priv;
464 unsigned long flags, size;
465
466 spin_lock_irqsave(&vp_dev->lock, flags);
467 list_del(&info->node);
468 spin_unlock_irqrestore(&vp_dev->lock, flags);
469
470 iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
471
472 if (vp_dev->msix_enabled) {
473 iowrite16(VIRTIO_MSI_NO_VECTOR,
474 vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
475 /* Flush the write out to device */
476 ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);
477 }
478
479 vring_del_virtqueue(vq);
480
481 /* Select and deactivate the queue */
482 iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
483
484 size = PAGE_ALIGN(vring_size(info->num, VIRTIO_PCI_VRING_ALIGN));
485 free_pages_exact(info->queue, size);
486 kfree(info);
487}
488
489/* the config->del_vqs() implementation */
490static void vp_del_vqs(struct virtio_device *vdev)
491{
492 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
493 struct virtqueue *vq, *n;
494 struct virtio_pci_vq_info *info;
495
496 list_for_each_entry_safe(vq, n, &vdev->vqs, list) {
497 info = vq->priv;
498 if (vp_dev->per_vq_vectors &&
499 info->msix_vector != VIRTIO_MSI_NO_VECTOR)
500 free_irq(vp_dev->msix_entries[info->msix_vector].vector,
501 vq);
502 vp_del_vq(vq);
503 }
504 vp_dev->per_vq_vectors = false;
505
506 vp_free_vectors(vdev);
507}
508
509static int vp_try_to_find_vqs(struct virtio_device *vdev, unsigned nvqs,
510 struct virtqueue *vqs[],
511 vq_callback_t *callbacks[],
512 const char *names[],
513 bool use_msix,
514 bool per_vq_vectors)
515{
516 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
517 u16 msix_vec;
518 int i, err, nvectors, allocated_vectors;
519
520 if (!use_msix) {
521 /* Old style: one normal interrupt for change and all vqs. */
522 err = vp_request_intx(vdev);
523 if (err)
524 goto error_request;
525 } else {
526 if (per_vq_vectors) {
527 /* Best option: one for change interrupt, one per vq. */
528 nvectors = 1;
529 for (i = 0; i < nvqs; ++i)
530 if (callbacks[i])
531 ++nvectors;
532 } else {
533 /* Second best: one for change, shared for all vqs. */
534 nvectors = 2;
535 }
536
537 err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors);
538 if (err)
539 goto error_request;
540 }
541
542 vp_dev->per_vq_vectors = per_vq_vectors;
543 allocated_vectors = vp_dev->msix_used_vectors;
544 for (i = 0; i < nvqs; ++i) {
545 if (!callbacks[i] || !vp_dev->msix_enabled)
546 msix_vec = VIRTIO_MSI_NO_VECTOR;
547 else if (vp_dev->per_vq_vectors)
548 msix_vec = allocated_vectors++;
549 else
550 msix_vec = VP_MSIX_VQ_VECTOR;
551 vqs[i] = setup_vq(vdev, i, callbacks[i], names[i], msix_vec);
552 if (IS_ERR(vqs[i])) {
553 err = PTR_ERR(vqs[i]);
554 goto error_find;
555 }
556
557 if (!vp_dev->per_vq_vectors || msix_vec == VIRTIO_MSI_NO_VECTOR)
558 continue;
559
560 /* allocate per-vq irq if available and necessary */
561 snprintf(vp_dev->msix_names[msix_vec],
562 sizeof *vp_dev->msix_names,
563 "%s-%s",
564 dev_name(&vp_dev->vdev.dev), names[i]);
565 err = request_irq(vp_dev->msix_entries[msix_vec].vector,
566 vring_interrupt, 0,
567 vp_dev->msix_names[msix_vec],
568 vqs[i]);
569 if (err) {
570 vp_del_vq(vqs[i]);
571 goto error_find;
572 }
573 }
574 return 0;
575
576error_find:
577 vp_del_vqs(vdev);
578
579error_request:
580 return err;
581}
582
583/* the config->find_vqs() implementation */
584static int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
585 struct virtqueue *vqs[],
586 vq_callback_t *callbacks[],
587 const char *names[])
588{
589 int err;
590
591 /* Try MSI-X with one vector per queue. */
592 err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, true, true);
593 if (!err)
594 return 0;
595 /* Fallback: MSI-X with one vector for config, one shared for queues. */
596 err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names,
597 true, false);
598 if (!err)
599 return 0;
600 /* Finally fall back to regular interrupts. */
601 return vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names,
602 false, false);
603}
604
605static const char *vp_bus_name(struct virtio_device *vdev)
606{
607 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
608
609 return pci_name(vp_dev->pci_dev);
610}
611
612static struct virtio_config_ops virtio_pci_config_ops = {
613 .get = vp_get,
614 .set = vp_set,
615 .get_status = vp_get_status,
616 .set_status = vp_set_status,
617 .reset = vp_reset,
618 .find_vqs = vp_find_vqs,
619 .del_vqs = vp_del_vqs,
620 .get_features = vp_get_features,
621 .finalize_features = vp_finalize_features,
622 .bus_name = vp_bus_name,
623};
624
625static void virtio_pci_release_dev(struct device *_d)
626{
627 /*
628 * No need for a release method as we allocate/free
629 * all devices together with the pci devices.
630 * Provide an empty one to avoid getting a warning from core.
631 */
632}
633
634/* the PCI probing function */
635static int __devinit virtio_pci_probe(struct pci_dev *pci_dev,
636 const struct pci_device_id *id)
637{
638 struct virtio_pci_device *vp_dev;
639 int err;
640
641 /* We only own devices >= 0x1000 and <= 0x103f: leave the rest. */
642 if (pci_dev->device < 0x1000 || pci_dev->device > 0x103f)
643 return -ENODEV;
644
645 if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION) {
646 printk(KERN_ERR "virtio_pci: expected ABI version %d, got %d\n",
647 VIRTIO_PCI_ABI_VERSION, pci_dev->revision);
648 return -ENODEV;
649 }
650
651 /* allocate our structure and fill it out */
652 vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL);
653 if (vp_dev == NULL)
654 return -ENOMEM;
655
656 vp_dev->vdev.dev.parent = &pci_dev->dev;
657 vp_dev->vdev.dev.release = virtio_pci_release_dev;
658 vp_dev->vdev.config = &virtio_pci_config_ops;
659 vp_dev->pci_dev = pci_dev;
660 INIT_LIST_HEAD(&vp_dev->virtqueues);
661 spin_lock_init(&vp_dev->lock);
662
663 /* Disable MSI/MSIX to bring device to a known good state. */
664 pci_msi_off(pci_dev);
665
666 /* enable the device */
667 err = pci_enable_device(pci_dev);
668 if (err)
669 goto out;
670
671 err = pci_request_regions(pci_dev, "virtio-pci");
672 if (err)
673 goto out_enable_device;
674
675 vp_dev->ioaddr = pci_iomap(pci_dev, 0, 0);
676 if (vp_dev->ioaddr == NULL)
677 goto out_req_regions;
678
679 pci_set_drvdata(pci_dev, vp_dev);
680 pci_set_master(pci_dev);
681
682 /* we use the subsystem vendor/device id as the virtio vendor/device
683 * id. this allows us to use the same PCI vendor/device id for all
684 * virtio devices and to identify the particular virtio driver by
685 * the subsystem ids */
686 vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
687 vp_dev->vdev.id.device = pci_dev->subsystem_device;
688
689 /* finally register the virtio device */
690 err = register_virtio_device(&vp_dev->vdev);
691 if (err)
692 goto out_set_drvdata;
693
694 return 0;
695
696out_set_drvdata:
697 pci_set_drvdata(pci_dev, NULL);
698 pci_iounmap(pci_dev, vp_dev->ioaddr);
699out_req_regions:
700 pci_release_regions(pci_dev);
701out_enable_device:
702 pci_disable_device(pci_dev);
703out:
704 kfree(vp_dev);
705 return err;
706}
707
708static void __devexit virtio_pci_remove(struct pci_dev *pci_dev)
709{
710 struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
711
712 unregister_virtio_device(&vp_dev->vdev);
713
714 vp_del_vqs(&vp_dev->vdev);
715 pci_set_drvdata(pci_dev, NULL);
716 pci_iounmap(pci_dev, vp_dev->ioaddr);
717 pci_release_regions(pci_dev);
718 pci_disable_device(pci_dev);
719 kfree(vp_dev);
720}
721
722#ifdef CONFIG_PM
723static int virtio_pci_freeze(struct device *dev)
724{
725 struct pci_dev *pci_dev = to_pci_dev(dev);
726 struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
727 struct virtio_driver *drv;
728 int ret;
729
730 drv = container_of(vp_dev->vdev.dev.driver,
731 struct virtio_driver, driver);
732
733 ret = 0;
734 vp_dev->saved_status = vp_get_status(&vp_dev->vdev);
735 if (drv && drv->freeze)
736 ret = drv->freeze(&vp_dev->vdev);
737
738 if (!ret)
739 pci_disable_device(pci_dev);
740 return ret;
741}
742
743static int virtio_pci_restore(struct device *dev)
744{
745 struct pci_dev *pci_dev = to_pci_dev(dev);
746 struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
747 struct virtio_driver *drv;
748 int ret;
749
750 drv = container_of(vp_dev->vdev.dev.driver,
751 struct virtio_driver, driver);
752
753 ret = pci_enable_device(pci_dev);
754 if (ret)
755 return ret;
756
757 pci_set_master(pci_dev);
758 vp_finalize_features(&vp_dev->vdev);
759
760 if (drv && drv->restore)
761 ret = drv->restore(&vp_dev->vdev);
762
763 /* Finally, tell the device we're all set */
764 if (!ret)
765 vp_set_status(&vp_dev->vdev, vp_dev->saved_status);
766
767 return ret;
768}
769
770static const struct dev_pm_ops virtio_pci_pm_ops = {
771 SET_SYSTEM_SLEEP_PM_OPS(virtio_pci_freeze, virtio_pci_restore)
772};
773#endif
774
775static struct pci_driver virtio_pci_driver = {
776 .name = "virtio-pci",
777 .id_table = virtio_pci_id_table,
778 .probe = virtio_pci_probe,
779 .remove = __devexit_p(virtio_pci_remove),
780#ifdef CONFIG_PM
781 .driver.pm = &virtio_pci_pm_ops,
782#endif
783};
784
785static int __init virtio_pci_init(void)
786{
787 return pci_register_driver(&virtio_pci_driver);
788}
789
790module_init(virtio_pci_init);
791
792static void __exit virtio_pci_exit(void)
793{
794 pci_unregister_driver(&virtio_pci_driver);
795}
796
797module_exit(virtio_pci_exit);