blob: 03d1984bd3635042b6bbe19f9966dfe89068e1ff [file] [log] [blame]
Anthony Liguori33436602007-11-12 21:30:26 -06001/*
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>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090020#include <linux/slab.h>
Anthony Liguori33436602007-11-12 21:30:26 -060021#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 */
Al Viro97968352008-03-29 03:09:48 +000041 void __iomem *ioaddr;
Anthony Liguori33436602007-11-12 21:30:26 -060042
43 /* a list of queues so we can dispatch IRQs */
44 spinlock_t lock;
45 struct list_head virtqueues;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +030046
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;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +030056 /* Vectors allocated, excluding per-vq vectors if any */
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +030057 unsigned msix_used_vectors;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +030058 /* Whether we have vector per vq */
59 bool per_vq_vectors;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +030060};
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,
Anthony Liguori33436602007-11-12 21:30:26 -060068};
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;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +030086
87 /* MSI-X vector (or none) */
Rusty Russellf68d2402009-09-23 22:26:29 -060088 unsigned msix_vector;
Anthony Liguori33436602007-11-12 21:30:26 -060089};
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
Anthony Liguori33436602007-11-12 21:30:26 -060099/* 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
Rusty Russellc45a6812008-05-02 21:50:50 -0500105/* virtio config->get_features() implementation */
106static u32 vp_get_features(struct virtio_device *vdev)
Anthony Liguori33436602007-11-12 21:30:26 -0600107{
108 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
Anthony Liguori33436602007-11-12 21:30:26 -0600109
Rusty Russellc45a6812008-05-02 21:50:50 -0500110 /* 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}
Anthony Liguori33436602007-11-12 21:30:26 -0600114
Rusty Russellc6248962008-07-25 12:06:07 -0500115/* virtio config->finalize_features() implementation */
116static void vp_finalize_features(struct virtio_device *vdev)
Rusty Russellc45a6812008-05-02 21:50:50 -0500117{
118 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
119
Rusty Russelle34f8722008-07-25 12:06:13 -0500120 /* Give virtio_ring a chance to accept features. */
121 vring_transport_features(vdev);
122
Rusty Russellc6248962008-07-25 12:06:07 -0500123 /* 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);
Anthony Liguori33436602007-11-12 21:30:26 -0600126}
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);
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300133 void __iomem *ioaddr = vp_dev->ioaddr +
134 VIRTIO_PCI_CONFIG(vp_dev) + offset;
Anthony Liguori33436602007-11-12 21:30:26 -0600135 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);
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300148 void __iomem *ioaddr = vp_dev->ioaddr +
149 VIRTIO_PCI_CONFIG(vp_dev) + offset;
Anthony Liguori33436602007-11-12 21:30:26 -0600150 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);
Harvey Harrison597d56e2008-03-31 17:53:55 -0700169 iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
Anthony Liguori33436602007-11-12 21:30:26 -0600170}
171
Michael S. Tsirkine6af5782011-11-17 17:41:15 +0200172/* wait for pending irq handlers */
173static void vp_synchronize_vectors(struct virtio_device *vdev)
174{
175 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
176 int i;
177
178 if (vp_dev->intx_enabled)
179 synchronize_irq(vp_dev->pci_dev->irq);
180
181 for (i = 0; i < vp_dev->msix_vectors; ++i)
182 synchronize_irq(vp_dev->msix_entries[i].vector);
183}
184
Anthony Liguori33436602007-11-12 21:30:26 -0600185static void vp_reset(struct virtio_device *vdev)
186{
187 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
188 /* 0 status means a reset. */
Harvey Harrison597d56e2008-03-31 17:53:55 -0700189 iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
Michael S. Tsirkine6af5782011-11-17 17:41:15 +0200190 /* Flush out the status write, and flush in device writes,
191 * including MSi-X interrupts, if any. */
192 ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS);
193 /* Flush pending VQ/configuration callbacks. */
194 vp_synchronize_vectors(vdev);
Anthony Liguori33436602007-11-12 21:30:26 -0600195}
196
197/* the notify function used when creating a virt queue */
198static void vp_notify(struct virtqueue *vq)
199{
200 struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
201 struct virtio_pci_vq_info *info = vq->priv;
202
203 /* we write the queue's selector into the notification register to
204 * signal the other end */
205 iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
206}
207
Michael S. Tsirkin77cf52462009-05-14 13:55:31 +0300208/* Handle a configuration change: Tell driver if it wants to know. */
209static irqreturn_t vp_config_changed(int irq, void *opaque)
210{
211 struct virtio_pci_device *vp_dev = opaque;
212 struct virtio_driver *drv;
213 drv = container_of(vp_dev->vdev.dev.driver,
214 struct virtio_driver, driver);
215
216 if (drv && drv->config_changed)
217 drv->config_changed(&vp_dev->vdev);
218 return IRQ_HANDLED;
219}
220
221/* Notify all virtqueues on an interrupt. */
222static irqreturn_t vp_vring_interrupt(int irq, void *opaque)
223{
224 struct virtio_pci_device *vp_dev = opaque;
225 struct virtio_pci_vq_info *info;
226 irqreturn_t ret = IRQ_NONE;
227 unsigned long flags;
228
229 spin_lock_irqsave(&vp_dev->lock, flags);
230 list_for_each_entry(info, &vp_dev->virtqueues, node) {
231 if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)
232 ret = IRQ_HANDLED;
233 }
234 spin_unlock_irqrestore(&vp_dev->lock, flags);
235
236 return ret;
237}
238
Anthony Liguori33436602007-11-12 21:30:26 -0600239/* A small wrapper to also acknowledge the interrupt when it's handled.
240 * I really need an EIO hook for the vring so I can ack the interrupt once we
241 * know that we'll be handling the IRQ but before we invoke the callback since
242 * the callback may notify the host which results in the host attempting to
243 * raise an interrupt that we would then mask once we acknowledged the
244 * interrupt. */
245static irqreturn_t vp_interrupt(int irq, void *opaque)
246{
247 struct virtio_pci_device *vp_dev = opaque;
Anthony Liguori33436602007-11-12 21:30:26 -0600248 u8 isr;
249
250 /* reading the ISR has the effect of also clearing it so it's very
251 * important to save off the value. */
252 isr = ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);
253
254 /* It's definitely not us if the ISR was not high */
255 if (!isr)
256 return IRQ_NONE;
257
258 /* Configuration change? Tell driver if it wants to know. */
Michael S. Tsirkin77cf52462009-05-14 13:55:31 +0300259 if (isr & VIRTIO_PCI_ISR_CONFIG)
260 vp_config_changed(irq, opaque);
Anthony Liguori33436602007-11-12 21:30:26 -0600261
Michael S. Tsirkin77cf52462009-05-14 13:55:31 +0300262 return vp_vring_interrupt(irq, opaque);
Anthony Liguori33436602007-11-12 21:30:26 -0600263}
264
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300265static void vp_free_vectors(struct virtio_device *vdev)
266{
267 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
268 int i;
269
270 if (vp_dev->intx_enabled) {
271 free_irq(vp_dev->pci_dev->irq, vp_dev);
272 vp_dev->intx_enabled = 0;
273 }
274
275 for (i = 0; i < vp_dev->msix_used_vectors; ++i)
276 free_irq(vp_dev->msix_entries[i].vector, vp_dev);
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300277
278 if (vp_dev->msix_enabled) {
279 /* Disable the vector used for configuration */
280 iowrite16(VIRTIO_MSI_NO_VECTOR,
281 vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
282 /* Flush the write out to device */
283 ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
284
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300285 pci_disable_msix(vp_dev->pci_dev);
Michael S. Tsirkinff52c3f2009-07-23 14:57:37 +0300286 vp_dev->msix_enabled = 0;
287 vp_dev->msix_vectors = 0;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300288 }
Michael S. Tsirkinff52c3f2009-07-23 14:57:37 +0300289
290 vp_dev->msix_used_vectors = 0;
291 kfree(vp_dev->msix_names);
292 vp_dev->msix_names = NULL;
293 kfree(vp_dev->msix_entries);
294 vp_dev->msix_entries = NULL;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300295}
296
Rusty Russellf68d2402009-09-23 22:26:29 -0600297static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors,
298 bool per_vq_vectors)
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300299{
300 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
301 const char *name = dev_name(&vp_dev->vdev.dev);
302 unsigned i, v;
303 int err = -ENOMEM;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300304
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300305 vp_dev->msix_entries = kmalloc(nvectors * sizeof *vp_dev->msix_entries,
306 GFP_KERNEL);
307 if (!vp_dev->msix_entries)
Michael S. Tsirkinff52c3f2009-07-23 14:57:37 +0300308 goto error;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300309 vp_dev->msix_names = kmalloc(nvectors * sizeof *vp_dev->msix_names,
310 GFP_KERNEL);
311 if (!vp_dev->msix_names)
Michael S. Tsirkinff52c3f2009-07-23 14:57:37 +0300312 goto error;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300313
314 for (i = 0; i < nvectors; ++i)
315 vp_dev->msix_entries[i].entry = i;
316
Rusty Russellf68d2402009-09-23 22:26:29 -0600317 /* pci_enable_msix returns positive if we can't get this many. */
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300318 err = pci_enable_msix(vp_dev->pci_dev, vp_dev->msix_entries, nvectors);
319 if (err > 0)
320 err = -ENOSPC;
321 if (err)
322 goto error;
323 vp_dev->msix_vectors = nvectors;
324 vp_dev->msix_enabled = 1;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300325
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300326 /* Set the vector used for configuration */
327 v = vp_dev->msix_used_vectors;
328 snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
329 "%s-config", name);
330 err = request_irq(vp_dev->msix_entries[v].vector,
331 vp_config_changed, 0, vp_dev->msix_names[v],
332 vp_dev);
333 if (err)
334 goto error;
335 ++vp_dev->msix_used_vectors;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300336
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300337 iowrite16(v, vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
338 /* Verify we had enough resources to assign the vector */
339 v = ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
340 if (v == VIRTIO_MSI_NO_VECTOR) {
341 err = -EBUSY;
342 goto error;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300343 }
344
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300345 if (!per_vq_vectors) {
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300346 /* Shared vector for all VQs */
347 v = vp_dev->msix_used_vectors;
348 snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
349 "%s-virtqueues", name);
350 err = request_irq(vp_dev->msix_entries[v].vector,
351 vp_vring_interrupt, 0, vp_dev->msix_names[v],
352 vp_dev);
353 if (err)
Michael S. Tsirkinff52c3f2009-07-23 14:57:37 +0300354 goto error;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300355 ++vp_dev->msix_used_vectors;
356 }
357 return 0;
Michael S. Tsirkinff52c3f2009-07-23 14:57:37 +0300358error:
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300359 vp_free_vectors(vdev);
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300360 return err;
361}
362
Rusty Russellf68d2402009-09-23 22:26:29 -0600363static int vp_request_intx(struct virtio_device *vdev)
364{
365 int err;
366 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
367
368 err = request_irq(vp_dev->pci_dev->irq, vp_interrupt,
369 IRQF_SHARED, dev_name(&vdev->dev), vp_dev);
370 if (!err)
371 vp_dev->intx_enabled = 1;
372 return err;
373}
374
375static struct virtqueue *setup_vq(struct virtio_device *vdev, unsigned index,
376 void (*callback)(struct virtqueue *vq),
377 const char *name,
378 u16 msix_vec)
Anthony Liguori33436602007-11-12 21:30:26 -0600379{
380 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
381 struct virtio_pci_vq_info *info;
382 struct virtqueue *vq;
Hollis Blanchard13b1eb32008-12-02 16:24:40 -0600383 unsigned long flags, size;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300384 u16 num;
Anthony Liguori33436602007-11-12 21:30:26 -0600385 int err;
386
387 /* Select the queue we're interested in */
388 iowrite16(index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
389
390 /* Check if queue is either not available or already active. */
391 num = ioread16(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NUM);
392 if (!num || ioread32(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN))
393 return ERR_PTR(-ENOENT);
394
395 /* allocate and fill out our structure the represents an active
396 * queue */
397 info = kmalloc(sizeof(struct virtio_pci_vq_info), GFP_KERNEL);
398 if (!info)
399 return ERR_PTR(-ENOMEM);
400
401 info->queue_index = index;
402 info->num = num;
Rusty Russellf68d2402009-09-23 22:26:29 -0600403 info->msix_vector = msix_vec;
Anthony Liguori33436602007-11-12 21:30:26 -0600404
Rusty Russell498af142008-12-30 09:25:57 -0600405 size = PAGE_ALIGN(vring_size(num, VIRTIO_PCI_VRING_ALIGN));
Hollis Blanchard13b1eb32008-12-02 16:24:40 -0600406 info->queue = alloc_pages_exact(size, GFP_KERNEL|__GFP_ZERO);
Anthony Liguori33436602007-11-12 21:30:26 -0600407 if (info->queue == NULL) {
408 err = -ENOMEM;
409 goto out_info;
410 }
411
412 /* activate the queue */
Rusty Russell480daab2008-12-30 09:25:56 -0600413 iowrite32(virt_to_phys(info->queue) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT,
Anthony Liguori33436602007-11-12 21:30:26 -0600414 vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
415
416 /* create the vring */
Rusty Russell87c7d572008-12-30 09:26:03 -0600417 vq = vring_new_virtqueue(info->num, VIRTIO_PCI_VRING_ALIGN,
Rusty Russell9499f5e2009-06-12 22:16:35 -0600418 vdev, info->queue, vp_notify, callback, name);
Anthony Liguori33436602007-11-12 21:30:26 -0600419 if (!vq) {
420 err = -ENOMEM;
421 goto out_activate_queue;
422 }
423
424 vq->priv = info;
425 info->vq = vq;
426
Rusty Russellf68d2402009-09-23 22:26:29 -0600427 if (msix_vec != VIRTIO_MSI_NO_VECTOR) {
428 iowrite16(msix_vec, vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
429 msix_vec = ioread16(vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
430 if (msix_vec == VIRTIO_MSI_NO_VECTOR) {
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300431 err = -EBUSY;
432 goto out_assign;
433 }
434 }
435
Krishna Kumar005b20a2011-10-05 11:08:59 +0530436 if (callback) {
437 spin_lock_irqsave(&vp_dev->lock, flags);
438 list_add(&info->node, &vp_dev->virtqueues);
439 spin_unlock_irqrestore(&vp_dev->lock, flags);
440 } else {
441 INIT_LIST_HEAD(&info->node);
442 }
Anthony Liguori33436602007-11-12 21:30:26 -0600443
444 return vq;
445
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300446out_assign:
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300447 vring_del_virtqueue(vq);
Anthony Liguori33436602007-11-12 21:30:26 -0600448out_activate_queue:
449 iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
Hollis Blanchard13b1eb32008-12-02 16:24:40 -0600450 free_pages_exact(info->queue, size);
Anthony Liguori33436602007-11-12 21:30:26 -0600451out_info:
452 kfree(info);
453 return ERR_PTR(err);
454}
455
Anthony Liguori33436602007-11-12 21:30:26 -0600456static void vp_del_vq(struct virtqueue *vq)
457{
458 struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
459 struct virtio_pci_vq_info *info = vq->priv;
Michael S. Tsirkinf6c82502009-07-26 15:48:01 +0300460 unsigned long flags, size;
461
462 spin_lock_irqsave(&vp_dev->lock, flags);
463 list_del(&info->node);
464 spin_unlock_irqrestore(&vp_dev->lock, flags);
Anthony Liguori33436602007-11-12 21:30:26 -0600465
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300466 iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
467
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300468 if (vp_dev->msix_enabled) {
469 iowrite16(VIRTIO_MSI_NO_VECTOR,
470 vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
471 /* Flush the write out to device */
472 ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);
473 }
474
Anthony Liguori33436602007-11-12 21:30:26 -0600475 vring_del_virtqueue(vq);
476
477 /* Select and deactivate the queue */
Anthony Liguori33436602007-11-12 21:30:26 -0600478 iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
479
Rusty Russell498af142008-12-30 09:25:57 -0600480 size = PAGE_ALIGN(vring_size(info->num, VIRTIO_PCI_VRING_ALIGN));
Hollis Blanchard13b1eb32008-12-02 16:24:40 -0600481 free_pages_exact(info->queue, size);
Anthony Liguori33436602007-11-12 21:30:26 -0600482 kfree(info);
483}
484
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300485/* the config->del_vqs() implementation */
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600486static void vp_del_vqs(struct virtio_device *vdev)
487{
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300488 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600489 struct virtqueue *vq, *n;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300490 struct virtio_pci_vq_info *info;
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600491
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300492 list_for_each_entry_safe(vq, n, &vdev->vqs, list) {
493 info = vq->priv;
Michael S. Tsirkin31198152010-02-25 19:08:55 +0200494 if (vp_dev->per_vq_vectors &&
495 info->msix_vector != VIRTIO_MSI_NO_VECTOR)
Rusty Russellf68d2402009-09-23 22:26:29 -0600496 free_irq(vp_dev->msix_entries[info->msix_vector].vector,
497 vq);
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600498 vp_del_vq(vq);
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300499 }
500 vp_dev->per_vq_vectors = false;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300501
502 vp_free_vectors(vdev);
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600503}
504
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300505static int vp_try_to_find_vqs(struct virtio_device *vdev, unsigned nvqs,
506 struct virtqueue *vqs[],
507 vq_callback_t *callbacks[],
508 const char *names[],
Rusty Russellf68d2402009-09-23 22:26:29 -0600509 bool use_msix,
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300510 bool per_vq_vectors)
511{
512 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
Rusty Russellf68d2402009-09-23 22:26:29 -0600513 u16 msix_vec;
514 int i, err, nvectors, allocated_vectors;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300515
Rusty Russellf68d2402009-09-23 22:26:29 -0600516 if (!use_msix) {
517 /* Old style: one normal interrupt for change and all vqs. */
518 err = vp_request_intx(vdev);
519 if (err)
520 goto error_request;
521 } else {
522 if (per_vq_vectors) {
523 /* Best option: one for change interrupt, one per vq. */
524 nvectors = 1;
525 for (i = 0; i < nvqs; ++i)
526 if (callbacks[i])
527 ++nvectors;
528 } else {
529 /* Second best: one for change, shared for all vqs. */
530 nvectors = 2;
531 }
532
533 err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors);
534 if (err)
535 goto error_request;
536 }
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300537
538 vp_dev->per_vq_vectors = per_vq_vectors;
539 allocated_vectors = vp_dev->msix_used_vectors;
540 for (i = 0; i < nvqs; ++i) {
541 if (!callbacks[i] || !vp_dev->msix_enabled)
Rusty Russellf68d2402009-09-23 22:26:29 -0600542 msix_vec = VIRTIO_MSI_NO_VECTOR;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300543 else if (vp_dev->per_vq_vectors)
Rusty Russellf68d2402009-09-23 22:26:29 -0600544 msix_vec = allocated_vectors++;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300545 else
Rusty Russellf68d2402009-09-23 22:26:29 -0600546 msix_vec = VP_MSIX_VQ_VECTOR;
547 vqs[i] = setup_vq(vdev, i, callbacks[i], names[i], msix_vec);
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300548 if (IS_ERR(vqs[i])) {
549 err = PTR_ERR(vqs[i]);
550 goto error_find;
551 }
Michael S. Tsirkin0b22bd02009-10-22 15:06:06 +0200552
553 if (!vp_dev->per_vq_vectors || msix_vec == VIRTIO_MSI_NO_VECTOR)
554 continue;
555
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300556 /* allocate per-vq irq if available and necessary */
Michael S. Tsirkin0b22bd02009-10-22 15:06:06 +0200557 snprintf(vp_dev->msix_names[msix_vec],
558 sizeof *vp_dev->msix_names,
559 "%s-%s",
560 dev_name(&vp_dev->vdev.dev), names[i]);
561 err = request_irq(vp_dev->msix_entries[msix_vec].vector,
562 vring_interrupt, 0,
563 vp_dev->msix_names[msix_vec],
564 vqs[i]);
565 if (err) {
566 vp_del_vq(vqs[i]);
567 goto error_find;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300568 }
569 }
570 return 0;
571
572error_find:
573 vp_del_vqs(vdev);
574
575error_request:
576 return err;
577}
578
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300579/* the config->find_vqs() implementation */
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600580static int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
581 struct virtqueue *vqs[],
582 vq_callback_t *callbacks[],
583 const char *names[])
584{
Rusty Russellf68d2402009-09-23 22:26:29 -0600585 int err;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300586
Rusty Russellf68d2402009-09-23 22:26:29 -0600587 /* Try MSI-X with one vector per queue. */
588 err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, true, true);
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300589 if (!err)
590 return 0;
Rusty Russellf68d2402009-09-23 22:26:29 -0600591 /* Fallback: MSI-X with one vector for config, one shared for queues. */
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300592 err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names,
Rusty Russellf68d2402009-09-23 22:26:29 -0600593 true, false);
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300594 if (!err)
595 return 0;
596 /* Finally fall back to regular interrupts. */
Rusty Russellf68d2402009-09-23 22:26:29 -0600597 return vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names,
598 false, false);
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600599}
600
Anthony Liguori33436602007-11-12 21:30:26 -0600601static struct virtio_config_ops virtio_pci_config_ops = {
Anthony Liguori33436602007-11-12 21:30:26 -0600602 .get = vp_get,
603 .set = vp_set,
604 .get_status = vp_get_status,
605 .set_status = vp_set_status,
606 .reset = vp_reset,
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600607 .find_vqs = vp_find_vqs,
608 .del_vqs = vp_del_vqs,
Rusty Russellc45a6812008-05-02 21:50:50 -0500609 .get_features = vp_get_features,
Rusty Russellc6248962008-07-25 12:06:07 -0500610 .finalize_features = vp_finalize_features,
Anthony Liguori33436602007-11-12 21:30:26 -0600611};
612
Mark McLoughlin29f9f122008-12-10 17:45:34 +0000613static void virtio_pci_release_dev(struct device *_d)
614{
Michael S. Tsirkin72103bd2011-11-07 18:37:05 +0200615 /*
616 * No need for a release method as we allocate/free
617 * all devices together with the pci devices.
618 * Provide an empty one to avoid getting a warning from core.
619 */
Mark McLoughlin29f9f122008-12-10 17:45:34 +0000620}
621
Anthony Liguori33436602007-11-12 21:30:26 -0600622/* the PCI probing function */
623static int __devinit virtio_pci_probe(struct pci_dev *pci_dev,
624 const struct pci_device_id *id)
625{
626 struct virtio_pci_device *vp_dev;
627 int err;
628
629 /* We only own devices >= 0x1000 and <= 0x103f: leave the rest. */
630 if (pci_dev->device < 0x1000 || pci_dev->device > 0x103f)
631 return -ENODEV;
632
Anthony Liguori55a7c062008-01-28 09:59:59 -0600633 if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION) {
634 printk(KERN_ERR "virtio_pci: expected ABI version %d, got %d\n",
635 VIRTIO_PCI_ABI_VERSION, pci_dev->revision);
636 return -ENODEV;
637 }
638
Anthony Liguori33436602007-11-12 21:30:26 -0600639 /* allocate our structure and fill it out */
640 vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL);
641 if (vp_dev == NULL)
642 return -ENOMEM;
643
Milton Miller8b3bb3e2011-01-07 02:55:06 -0600644 vp_dev->vdev.dev.parent = &pci_dev->dev;
Mark McLoughlin29f9f122008-12-10 17:45:34 +0000645 vp_dev->vdev.dev.release = virtio_pci_release_dev;
Anthony Liguori33436602007-11-12 21:30:26 -0600646 vp_dev->vdev.config = &virtio_pci_config_ops;
647 vp_dev->pci_dev = pci_dev;
648 INIT_LIST_HEAD(&vp_dev->virtqueues);
649 spin_lock_init(&vp_dev->lock);
650
Michael S. Tsirkinb03214d2010-06-23 22:49:06 -0600651 /* Disable MSI/MSIX to bring device to a known good state. */
652 pci_msi_off(pci_dev);
653
Anthony Liguori33436602007-11-12 21:30:26 -0600654 /* enable the device */
655 err = pci_enable_device(pci_dev);
656 if (err)
657 goto out;
658
659 err = pci_request_regions(pci_dev, "virtio-pci");
660 if (err)
661 goto out_enable_device;
662
663 vp_dev->ioaddr = pci_iomap(pci_dev, 0, 0);
664 if (vp_dev->ioaddr == NULL)
665 goto out_req_regions;
666
667 pci_set_drvdata(pci_dev, vp_dev);
Michael S. Tsirkinbc505f32009-11-29 17:52:00 +0200668 pci_set_master(pci_dev);
Anthony Liguori33436602007-11-12 21:30:26 -0600669
670 /* we use the subsystem vendor/device id as the virtio vendor/device
671 * id. this allows us to use the same PCI vendor/device id for all
672 * virtio devices and to identify the particular virtio driver by
Thomas Weber88393162010-03-16 11:47:56 +0100673 * the subsystem ids */
Anthony Liguori33436602007-11-12 21:30:26 -0600674 vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
675 vp_dev->vdev.id.device = pci_dev->subsystem_device;
676
Anthony Liguori33436602007-11-12 21:30:26 -0600677 /* finally register the virtio device */
678 err = register_virtio_device(&vp_dev->vdev);
679 if (err)
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300680 goto out_set_drvdata;
Anthony Liguori33436602007-11-12 21:30:26 -0600681
682 return 0;
683
Anthony Liguori33436602007-11-12 21:30:26 -0600684out_set_drvdata:
685 pci_set_drvdata(pci_dev, NULL);
686 pci_iounmap(pci_dev, vp_dev->ioaddr);
687out_req_regions:
688 pci_release_regions(pci_dev);
689out_enable_device:
690 pci_disable_device(pci_dev);
691out:
692 kfree(vp_dev);
693 return err;
694}
695
696static void __devexit virtio_pci_remove(struct pci_dev *pci_dev)
697{
698 struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
699
Anthony Liguoribd6c2692008-03-19 20:35:04 -0500700 unregister_virtio_device(&vp_dev->vdev);
Amit Shah31a3ddd2011-03-14 17:45:02 +0530701
702 vp_del_vqs(&vp_dev->vdev);
703 pci_set_drvdata(pci_dev, NULL);
704 pci_iounmap(pci_dev, vp_dev->ioaddr);
705 pci_release_regions(pci_dev);
706 pci_disable_device(pci_dev);
Michael S. Tsirkin72103bd2011-11-07 18:37:05 +0200707 kfree(vp_dev);
Anthony Liguori33436602007-11-12 21:30:26 -0600708}
709
710#ifdef CONFIG_PM
711static int virtio_pci_suspend(struct pci_dev *pci_dev, pm_message_t state)
712{
713 pci_save_state(pci_dev);
714 pci_set_power_state(pci_dev, PCI_D3hot);
715 return 0;
716}
717
718static int virtio_pci_resume(struct pci_dev *pci_dev)
719{
720 pci_restore_state(pci_dev);
721 pci_set_power_state(pci_dev, PCI_D0);
722 return 0;
723}
724#endif
725
726static struct pci_driver virtio_pci_driver = {
727 .name = "virtio-pci",
728 .id_table = virtio_pci_id_table,
729 .probe = virtio_pci_probe,
Jamie Lokier1f08b832010-01-08 22:01:43 +0000730 .remove = __devexit_p(virtio_pci_remove),
Anthony Liguori33436602007-11-12 21:30:26 -0600731#ifdef CONFIG_PM
732 .suspend = virtio_pci_suspend,
733 .resume = virtio_pci_resume,
734#endif
735};
736
737static int __init virtio_pci_init(void)
738{
Milton Miller8b3bb3e2011-01-07 02:55:06 -0600739 return pci_register_driver(&virtio_pci_driver);
Anthony Liguori33436602007-11-12 21:30:26 -0600740}
741
742module_init(virtio_pci_init);
743
744static void __exit virtio_pci_exit(void)
745{
Anthony Liguori33436602007-11-12 21:30:26 -0600746 pci_unregister_driver(&virtio_pci_driver);
Anthony Liguori33436602007-11-12 21:30:26 -0600747}
748
749module_exit(virtio_pci_exit);