blob: 24747aef1952880ca686a1b8d9506acb1e174f55 [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
99/* A PCI device has it's own struct device and so does a virtio device so
100 * we create a place for the virtio devices to show up in sysfs. I think it
101 * would make more sense for virtio to not insist on having it's own device. */
Mark McLoughlin63d12552008-12-15 12:58:27 +0000102static struct device *virtio_pci_root;
Anthony Liguori33436602007-11-12 21:30:26 -0600103
Anthony Liguori33436602007-11-12 21:30:26 -0600104/* Convert a generic virtio device to our structure */
105static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev)
106{
107 return container_of(vdev, struct virtio_pci_device, vdev);
108}
109
Rusty Russellc45a6812008-05-02 21:50:50 -0500110/* virtio config->get_features() implementation */
111static u32 vp_get_features(struct virtio_device *vdev)
Anthony Liguori33436602007-11-12 21:30:26 -0600112{
113 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
Anthony Liguori33436602007-11-12 21:30:26 -0600114
Rusty Russellc45a6812008-05-02 21:50:50 -0500115 /* When someone needs more than 32 feature bits, we'll need to
116 * steal a bit to indicate that the rest are somewhere else. */
117 return ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES);
118}
Anthony Liguori33436602007-11-12 21:30:26 -0600119
Rusty Russellc6248962008-07-25 12:06:07 -0500120/* virtio config->finalize_features() implementation */
121static void vp_finalize_features(struct virtio_device *vdev)
Rusty Russellc45a6812008-05-02 21:50:50 -0500122{
123 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
124
Rusty Russelle34f8722008-07-25 12:06:13 -0500125 /* Give virtio_ring a chance to accept features. */
126 vring_transport_features(vdev);
127
Rusty Russellc6248962008-07-25 12:06:07 -0500128 /* We only support 32 feature bits. */
129 BUILD_BUG_ON(ARRAY_SIZE(vdev->features) != 1);
130 iowrite32(vdev->features[0], vp_dev->ioaddr+VIRTIO_PCI_GUEST_FEATURES);
Anthony Liguori33436602007-11-12 21:30:26 -0600131}
132
133/* virtio config->get() implementation */
134static void vp_get(struct virtio_device *vdev, unsigned offset,
135 void *buf, unsigned len)
136{
137 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300138 void __iomem *ioaddr = vp_dev->ioaddr +
139 VIRTIO_PCI_CONFIG(vp_dev) + offset;
Anthony Liguori33436602007-11-12 21:30:26 -0600140 u8 *ptr = buf;
141 int i;
142
143 for (i = 0; i < len; i++)
144 ptr[i] = ioread8(ioaddr + i);
145}
146
147/* the config->set() implementation. it's symmetric to the config->get()
148 * implementation */
149static void vp_set(struct virtio_device *vdev, unsigned offset,
150 const void *buf, unsigned len)
151{
152 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300153 void __iomem *ioaddr = vp_dev->ioaddr +
154 VIRTIO_PCI_CONFIG(vp_dev) + offset;
Anthony Liguori33436602007-11-12 21:30:26 -0600155 const u8 *ptr = buf;
156 int i;
157
158 for (i = 0; i < len; i++)
159 iowrite8(ptr[i], ioaddr + i);
160}
161
162/* config->{get,set}_status() implementations */
163static u8 vp_get_status(struct virtio_device *vdev)
164{
165 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
166 return ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS);
167}
168
169static void vp_set_status(struct virtio_device *vdev, u8 status)
170{
171 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
172 /* We should never be setting status to 0. */
173 BUG_ON(status == 0);
Harvey Harrison597d56e2008-03-31 17:53:55 -0700174 iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
Anthony Liguori33436602007-11-12 21:30:26 -0600175}
176
177static void vp_reset(struct virtio_device *vdev)
178{
179 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
180 /* 0 status means a reset. */
Harvey Harrison597d56e2008-03-31 17:53:55 -0700181 iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
Anthony Liguori33436602007-11-12 21:30:26 -0600182}
183
184/* the notify function used when creating a virt queue */
185static void vp_notify(struct virtqueue *vq)
186{
187 struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
188 struct virtio_pci_vq_info *info = vq->priv;
189
190 /* we write the queue's selector into the notification register to
191 * signal the other end */
192 iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
193}
194
Michael S. Tsirkin77cf52462009-05-14 13:55:31 +0300195/* Handle a configuration change: Tell driver if it wants to know. */
196static irqreturn_t vp_config_changed(int irq, void *opaque)
197{
198 struct virtio_pci_device *vp_dev = opaque;
199 struct virtio_driver *drv;
200 drv = container_of(vp_dev->vdev.dev.driver,
201 struct virtio_driver, driver);
202
203 if (drv && drv->config_changed)
204 drv->config_changed(&vp_dev->vdev);
205 return IRQ_HANDLED;
206}
207
208/* Notify all virtqueues on an interrupt. */
209static irqreturn_t vp_vring_interrupt(int irq, void *opaque)
210{
211 struct virtio_pci_device *vp_dev = opaque;
212 struct virtio_pci_vq_info *info;
213 irqreturn_t ret = IRQ_NONE;
214 unsigned long flags;
215
216 spin_lock_irqsave(&vp_dev->lock, flags);
217 list_for_each_entry(info, &vp_dev->virtqueues, node) {
218 if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)
219 ret = IRQ_HANDLED;
220 }
221 spin_unlock_irqrestore(&vp_dev->lock, flags);
222
223 return ret;
224}
225
Anthony Liguori33436602007-11-12 21:30:26 -0600226/* A small wrapper to also acknowledge the interrupt when it's handled.
227 * I really need an EIO hook for the vring so I can ack the interrupt once we
228 * know that we'll be handling the IRQ but before we invoke the callback since
229 * the callback may notify the host which results in the host attempting to
230 * raise an interrupt that we would then mask once we acknowledged the
231 * interrupt. */
232static irqreturn_t vp_interrupt(int irq, void *opaque)
233{
234 struct virtio_pci_device *vp_dev = opaque;
Anthony Liguori33436602007-11-12 21:30:26 -0600235 u8 isr;
236
237 /* reading the ISR has the effect of also clearing it so it's very
238 * important to save off the value. */
239 isr = ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);
240
241 /* It's definitely not us if the ISR was not high */
242 if (!isr)
243 return IRQ_NONE;
244
245 /* Configuration change? Tell driver if it wants to know. */
Michael S. Tsirkin77cf52462009-05-14 13:55:31 +0300246 if (isr & VIRTIO_PCI_ISR_CONFIG)
247 vp_config_changed(irq, opaque);
Anthony Liguori33436602007-11-12 21:30:26 -0600248
Michael S. Tsirkin77cf52462009-05-14 13:55:31 +0300249 return vp_vring_interrupt(irq, opaque);
Anthony Liguori33436602007-11-12 21:30:26 -0600250}
251
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300252static void vp_free_vectors(struct virtio_device *vdev)
253{
254 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
255 int i;
256
257 if (vp_dev->intx_enabled) {
258 free_irq(vp_dev->pci_dev->irq, vp_dev);
259 vp_dev->intx_enabled = 0;
260 }
261
262 for (i = 0; i < vp_dev->msix_used_vectors; ++i)
263 free_irq(vp_dev->msix_entries[i].vector, vp_dev);
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300264
265 if (vp_dev->msix_enabled) {
266 /* Disable the vector used for configuration */
267 iowrite16(VIRTIO_MSI_NO_VECTOR,
268 vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
269 /* Flush the write out to device */
270 ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
271
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300272 pci_disable_msix(vp_dev->pci_dev);
Michael S. Tsirkinff52c3f2009-07-23 14:57:37 +0300273 vp_dev->msix_enabled = 0;
274 vp_dev->msix_vectors = 0;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300275 }
Michael S. Tsirkinff52c3f2009-07-23 14:57:37 +0300276
277 vp_dev->msix_used_vectors = 0;
278 kfree(vp_dev->msix_names);
279 vp_dev->msix_names = NULL;
280 kfree(vp_dev->msix_entries);
281 vp_dev->msix_entries = NULL;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300282}
283
Rusty Russellf68d2402009-09-23 22:26:29 -0600284static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors,
285 bool per_vq_vectors)
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300286{
287 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
288 const char *name = dev_name(&vp_dev->vdev.dev);
289 unsigned i, v;
290 int err = -ENOMEM;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300291
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300292 vp_dev->msix_entries = kmalloc(nvectors * sizeof *vp_dev->msix_entries,
293 GFP_KERNEL);
294 if (!vp_dev->msix_entries)
Michael S. Tsirkinff52c3f2009-07-23 14:57:37 +0300295 goto error;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300296 vp_dev->msix_names = kmalloc(nvectors * sizeof *vp_dev->msix_names,
297 GFP_KERNEL);
298 if (!vp_dev->msix_names)
Michael S. Tsirkinff52c3f2009-07-23 14:57:37 +0300299 goto error;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300300
301 for (i = 0; i < nvectors; ++i)
302 vp_dev->msix_entries[i].entry = i;
303
Rusty Russellf68d2402009-09-23 22:26:29 -0600304 /* pci_enable_msix returns positive if we can't get this many. */
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300305 err = pci_enable_msix(vp_dev->pci_dev, vp_dev->msix_entries, nvectors);
306 if (err > 0)
307 err = -ENOSPC;
308 if (err)
309 goto error;
310 vp_dev->msix_vectors = nvectors;
311 vp_dev->msix_enabled = 1;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300312
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300313 /* Set the vector used for configuration */
314 v = vp_dev->msix_used_vectors;
315 snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
316 "%s-config", name);
317 err = request_irq(vp_dev->msix_entries[v].vector,
318 vp_config_changed, 0, vp_dev->msix_names[v],
319 vp_dev);
320 if (err)
321 goto error;
322 ++vp_dev->msix_used_vectors;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300323
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300324 iowrite16(v, vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
325 /* Verify we had enough resources to assign the vector */
326 v = ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR);
327 if (v == VIRTIO_MSI_NO_VECTOR) {
328 err = -EBUSY;
329 goto error;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300330 }
331
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300332 if (!per_vq_vectors) {
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300333 /* Shared vector for all VQs */
334 v = vp_dev->msix_used_vectors;
335 snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names,
336 "%s-virtqueues", name);
337 err = request_irq(vp_dev->msix_entries[v].vector,
338 vp_vring_interrupt, 0, vp_dev->msix_names[v],
339 vp_dev);
340 if (err)
Michael S. Tsirkinff52c3f2009-07-23 14:57:37 +0300341 goto error;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300342 ++vp_dev->msix_used_vectors;
343 }
344 return 0;
Michael S. Tsirkinff52c3f2009-07-23 14:57:37 +0300345error:
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300346 vp_free_vectors(vdev);
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300347 return err;
348}
349
Rusty Russellf68d2402009-09-23 22:26:29 -0600350static int vp_request_intx(struct virtio_device *vdev)
351{
352 int err;
353 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
354
355 err = request_irq(vp_dev->pci_dev->irq, vp_interrupt,
356 IRQF_SHARED, dev_name(&vdev->dev), vp_dev);
357 if (!err)
358 vp_dev->intx_enabled = 1;
359 return err;
360}
361
362static struct virtqueue *setup_vq(struct virtio_device *vdev, unsigned index,
363 void (*callback)(struct virtqueue *vq),
364 const char *name,
365 u16 msix_vec)
Anthony Liguori33436602007-11-12 21:30:26 -0600366{
367 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
368 struct virtio_pci_vq_info *info;
369 struct virtqueue *vq;
Hollis Blanchard13b1eb32008-12-02 16:24:40 -0600370 unsigned long flags, size;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300371 u16 num;
Anthony Liguori33436602007-11-12 21:30:26 -0600372 int err;
373
374 /* Select the queue we're interested in */
375 iowrite16(index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
376
377 /* Check if queue is either not available or already active. */
378 num = ioread16(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NUM);
379 if (!num || ioread32(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN))
380 return ERR_PTR(-ENOENT);
381
382 /* allocate and fill out our structure the represents an active
383 * queue */
384 info = kmalloc(sizeof(struct virtio_pci_vq_info), GFP_KERNEL);
385 if (!info)
386 return ERR_PTR(-ENOMEM);
387
388 info->queue_index = index;
389 info->num = num;
Rusty Russellf68d2402009-09-23 22:26:29 -0600390 info->msix_vector = msix_vec;
Anthony Liguori33436602007-11-12 21:30:26 -0600391
Rusty Russell498af142008-12-30 09:25:57 -0600392 size = PAGE_ALIGN(vring_size(num, VIRTIO_PCI_VRING_ALIGN));
Hollis Blanchard13b1eb32008-12-02 16:24:40 -0600393 info->queue = alloc_pages_exact(size, GFP_KERNEL|__GFP_ZERO);
Anthony Liguori33436602007-11-12 21:30:26 -0600394 if (info->queue == NULL) {
395 err = -ENOMEM;
396 goto out_info;
397 }
398
399 /* activate the queue */
Rusty Russell480daab2008-12-30 09:25:56 -0600400 iowrite32(virt_to_phys(info->queue) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT,
Anthony Liguori33436602007-11-12 21:30:26 -0600401 vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
402
403 /* create the vring */
Rusty Russell87c7d572008-12-30 09:26:03 -0600404 vq = vring_new_virtqueue(info->num, VIRTIO_PCI_VRING_ALIGN,
Rusty Russell9499f5e2009-06-12 22:16:35 -0600405 vdev, info->queue, vp_notify, callback, name);
Anthony Liguori33436602007-11-12 21:30:26 -0600406 if (!vq) {
407 err = -ENOMEM;
408 goto out_activate_queue;
409 }
410
411 vq->priv = info;
412 info->vq = vq;
413
Rusty Russellf68d2402009-09-23 22:26:29 -0600414 if (msix_vec != VIRTIO_MSI_NO_VECTOR) {
415 iowrite16(msix_vec, vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
416 msix_vec = ioread16(vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
417 if (msix_vec == VIRTIO_MSI_NO_VECTOR) {
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300418 err = -EBUSY;
419 goto out_assign;
420 }
421 }
422
Anthony Liguori27ebe302008-03-02 16:37:48 -0600423 spin_lock_irqsave(&vp_dev->lock, flags);
Anthony Liguori33436602007-11-12 21:30:26 -0600424 list_add(&info->node, &vp_dev->virtqueues);
Anthony Liguori27ebe302008-03-02 16:37:48 -0600425 spin_unlock_irqrestore(&vp_dev->lock, flags);
Anthony Liguori33436602007-11-12 21:30:26 -0600426
427 return vq;
428
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300429out_assign:
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300430 vring_del_virtqueue(vq);
Anthony Liguori33436602007-11-12 21:30:26 -0600431out_activate_queue:
432 iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
Hollis Blanchard13b1eb32008-12-02 16:24:40 -0600433 free_pages_exact(info->queue, size);
Anthony Liguori33436602007-11-12 21:30:26 -0600434out_info:
435 kfree(info);
436 return ERR_PTR(err);
437}
438
Anthony Liguori33436602007-11-12 21:30:26 -0600439static void vp_del_vq(struct virtqueue *vq)
440{
441 struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
442 struct virtio_pci_vq_info *info = vq->priv;
Michael S. Tsirkinf6c82502009-07-26 15:48:01 +0300443 unsigned long flags, size;
444
445 spin_lock_irqsave(&vp_dev->lock, flags);
446 list_del(&info->node);
447 spin_unlock_irqrestore(&vp_dev->lock, flags);
Anthony Liguori33436602007-11-12 21:30:26 -0600448
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300449 iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
450
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300451 if (vp_dev->msix_enabled) {
452 iowrite16(VIRTIO_MSI_NO_VECTOR,
453 vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR);
454 /* Flush the write out to device */
455 ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);
456 }
457
Anthony Liguori33436602007-11-12 21:30:26 -0600458 vring_del_virtqueue(vq);
459
460 /* Select and deactivate the queue */
Anthony Liguori33436602007-11-12 21:30:26 -0600461 iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
462
Rusty Russell498af142008-12-30 09:25:57 -0600463 size = PAGE_ALIGN(vring_size(info->num, VIRTIO_PCI_VRING_ALIGN));
Hollis Blanchard13b1eb32008-12-02 16:24:40 -0600464 free_pages_exact(info->queue, size);
Anthony Liguori33436602007-11-12 21:30:26 -0600465 kfree(info);
466}
467
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300468/* the config->del_vqs() implementation */
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600469static void vp_del_vqs(struct virtio_device *vdev)
470{
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300471 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600472 struct virtqueue *vq, *n;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300473 struct virtio_pci_vq_info *info;
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600474
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300475 list_for_each_entry_safe(vq, n, &vdev->vqs, list) {
476 info = vq->priv;
Michael S. Tsirkin31198152010-02-25 19:08:55 +0200477 if (vp_dev->per_vq_vectors &&
478 info->msix_vector != VIRTIO_MSI_NO_VECTOR)
Rusty Russellf68d2402009-09-23 22:26:29 -0600479 free_irq(vp_dev->msix_entries[info->msix_vector].vector,
480 vq);
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600481 vp_del_vq(vq);
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300482 }
483 vp_dev->per_vq_vectors = false;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300484
485 vp_free_vectors(vdev);
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600486}
487
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300488static int vp_try_to_find_vqs(struct virtio_device *vdev, unsigned nvqs,
489 struct virtqueue *vqs[],
490 vq_callback_t *callbacks[],
491 const char *names[],
Rusty Russellf68d2402009-09-23 22:26:29 -0600492 bool use_msix,
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300493 bool per_vq_vectors)
494{
495 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
Rusty Russellf68d2402009-09-23 22:26:29 -0600496 u16 msix_vec;
497 int i, err, nvectors, allocated_vectors;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300498
Rusty Russellf68d2402009-09-23 22:26:29 -0600499 if (!use_msix) {
500 /* Old style: one normal interrupt for change and all vqs. */
501 err = vp_request_intx(vdev);
502 if (err)
503 goto error_request;
504 } else {
505 if (per_vq_vectors) {
506 /* Best option: one for change interrupt, one per vq. */
507 nvectors = 1;
508 for (i = 0; i < nvqs; ++i)
509 if (callbacks[i])
510 ++nvectors;
511 } else {
512 /* Second best: one for change, shared for all vqs. */
513 nvectors = 2;
514 }
515
516 err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors);
517 if (err)
518 goto error_request;
519 }
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300520
521 vp_dev->per_vq_vectors = per_vq_vectors;
522 allocated_vectors = vp_dev->msix_used_vectors;
523 for (i = 0; i < nvqs; ++i) {
524 if (!callbacks[i] || !vp_dev->msix_enabled)
Rusty Russellf68d2402009-09-23 22:26:29 -0600525 msix_vec = VIRTIO_MSI_NO_VECTOR;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300526 else if (vp_dev->per_vq_vectors)
Rusty Russellf68d2402009-09-23 22:26:29 -0600527 msix_vec = allocated_vectors++;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300528 else
Rusty Russellf68d2402009-09-23 22:26:29 -0600529 msix_vec = VP_MSIX_VQ_VECTOR;
530 vqs[i] = setup_vq(vdev, i, callbacks[i], names[i], msix_vec);
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300531 if (IS_ERR(vqs[i])) {
532 err = PTR_ERR(vqs[i]);
533 goto error_find;
534 }
Michael S. Tsirkin0b22bd02009-10-22 15:06:06 +0200535
536 if (!vp_dev->per_vq_vectors || msix_vec == VIRTIO_MSI_NO_VECTOR)
537 continue;
538
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300539 /* allocate per-vq irq if available and necessary */
Michael S. Tsirkin0b22bd02009-10-22 15:06:06 +0200540 snprintf(vp_dev->msix_names[msix_vec],
541 sizeof *vp_dev->msix_names,
542 "%s-%s",
543 dev_name(&vp_dev->vdev.dev), names[i]);
544 err = request_irq(vp_dev->msix_entries[msix_vec].vector,
545 vring_interrupt, 0,
546 vp_dev->msix_names[msix_vec],
547 vqs[i]);
548 if (err) {
549 vp_del_vq(vqs[i]);
550 goto error_find;
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300551 }
552 }
553 return 0;
554
555error_find:
556 vp_del_vqs(vdev);
557
558error_request:
559 return err;
560}
561
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300562/* the config->find_vqs() implementation */
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600563static int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs,
564 struct virtqueue *vqs[],
565 vq_callback_t *callbacks[],
566 const char *names[])
567{
Rusty Russellf68d2402009-09-23 22:26:29 -0600568 int err;
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300569
Rusty Russellf68d2402009-09-23 22:26:29 -0600570 /* Try MSI-X with one vector per queue. */
571 err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, true, true);
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300572 if (!err)
573 return 0;
Rusty Russellf68d2402009-09-23 22:26:29 -0600574 /* Fallback: MSI-X with one vector for config, one shared for queues. */
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300575 err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names,
Rusty Russellf68d2402009-09-23 22:26:29 -0600576 true, false);
Michael S. Tsirkine969fed2009-07-26 15:48:08 +0300577 if (!err)
578 return 0;
579 /* Finally fall back to regular interrupts. */
Rusty Russellf68d2402009-09-23 22:26:29 -0600580 return vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names,
581 false, false);
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600582}
583
Anthony Liguori33436602007-11-12 21:30:26 -0600584static struct virtio_config_ops virtio_pci_config_ops = {
Anthony Liguori33436602007-11-12 21:30:26 -0600585 .get = vp_get,
586 .set = vp_set,
587 .get_status = vp_get_status,
588 .set_status = vp_set_status,
589 .reset = vp_reset,
Michael S. Tsirkind2a7ddd2009-06-12 22:16:36 -0600590 .find_vqs = vp_find_vqs,
591 .del_vqs = vp_del_vqs,
Rusty Russellc45a6812008-05-02 21:50:50 -0500592 .get_features = vp_get_features,
Rusty Russellc6248962008-07-25 12:06:07 -0500593 .finalize_features = vp_finalize_features,
Anthony Liguori33436602007-11-12 21:30:26 -0600594};
595
Mark McLoughlin29f9f122008-12-10 17:45:34 +0000596static void virtio_pci_release_dev(struct device *_d)
597{
598 struct virtio_device *dev = container_of(_d, struct virtio_device, dev);
599 struct virtio_pci_device *vp_dev = to_vp_device(dev);
600 struct pci_dev *pci_dev = vp_dev->pci_dev;
601
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300602 vp_del_vqs(dev);
Mark McLoughlin29f9f122008-12-10 17:45:34 +0000603 pci_set_drvdata(pci_dev, NULL);
604 pci_iounmap(pci_dev, vp_dev->ioaddr);
605 pci_release_regions(pci_dev);
606 pci_disable_device(pci_dev);
607 kfree(vp_dev);
608}
609
Anthony Liguori33436602007-11-12 21:30:26 -0600610/* the PCI probing function */
611static int __devinit virtio_pci_probe(struct pci_dev *pci_dev,
612 const struct pci_device_id *id)
613{
614 struct virtio_pci_device *vp_dev;
615 int err;
616
617 /* We only own devices >= 0x1000 and <= 0x103f: leave the rest. */
618 if (pci_dev->device < 0x1000 || pci_dev->device > 0x103f)
619 return -ENODEV;
620
Anthony Liguori55a7c062008-01-28 09:59:59 -0600621 if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION) {
622 printk(KERN_ERR "virtio_pci: expected ABI version %d, got %d\n",
623 VIRTIO_PCI_ABI_VERSION, pci_dev->revision);
624 return -ENODEV;
625 }
626
Anthony Liguori33436602007-11-12 21:30:26 -0600627 /* allocate our structure and fill it out */
628 vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL);
629 if (vp_dev == NULL)
630 return -ENOMEM;
631
Mark McLoughlin63d12552008-12-15 12:58:27 +0000632 vp_dev->vdev.dev.parent = virtio_pci_root;
Mark McLoughlin29f9f122008-12-10 17:45:34 +0000633 vp_dev->vdev.dev.release = virtio_pci_release_dev;
Anthony Liguori33436602007-11-12 21:30:26 -0600634 vp_dev->vdev.config = &virtio_pci_config_ops;
635 vp_dev->pci_dev = pci_dev;
636 INIT_LIST_HEAD(&vp_dev->virtqueues);
637 spin_lock_init(&vp_dev->lock);
638
639 /* enable the device */
640 err = pci_enable_device(pci_dev);
641 if (err)
642 goto out;
643
644 err = pci_request_regions(pci_dev, "virtio-pci");
645 if (err)
646 goto out_enable_device;
647
648 vp_dev->ioaddr = pci_iomap(pci_dev, 0, 0);
649 if (vp_dev->ioaddr == NULL)
650 goto out_req_regions;
651
652 pci_set_drvdata(pci_dev, vp_dev);
Michael S. Tsirkinbc505f32009-11-29 17:52:00 +0200653 pci_set_master(pci_dev);
Anthony Liguori33436602007-11-12 21:30:26 -0600654
655 /* we use the subsystem vendor/device id as the virtio vendor/device
656 * id. this allows us to use the same PCI vendor/device id for all
657 * virtio devices and to identify the particular virtio driver by
658 * the subsytem ids */
659 vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
660 vp_dev->vdev.id.device = pci_dev->subsystem_device;
661
Anthony Liguori33436602007-11-12 21:30:26 -0600662 /* finally register the virtio device */
663 err = register_virtio_device(&vp_dev->vdev);
664 if (err)
Michael S. Tsirkin82af8ce2009-05-14 13:55:41 +0300665 goto out_set_drvdata;
Anthony Liguori33436602007-11-12 21:30:26 -0600666
667 return 0;
668
Anthony Liguori33436602007-11-12 21:30:26 -0600669out_set_drvdata:
670 pci_set_drvdata(pci_dev, NULL);
671 pci_iounmap(pci_dev, vp_dev->ioaddr);
672out_req_regions:
673 pci_release_regions(pci_dev);
674out_enable_device:
675 pci_disable_device(pci_dev);
676out:
677 kfree(vp_dev);
678 return err;
679}
680
681static void __devexit virtio_pci_remove(struct pci_dev *pci_dev)
682{
683 struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
684
Anthony Liguoribd6c2692008-03-19 20:35:04 -0500685 unregister_virtio_device(&vp_dev->vdev);
Anthony Liguori33436602007-11-12 21:30:26 -0600686}
687
688#ifdef CONFIG_PM
689static int virtio_pci_suspend(struct pci_dev *pci_dev, pm_message_t state)
690{
691 pci_save_state(pci_dev);
692 pci_set_power_state(pci_dev, PCI_D3hot);
693 return 0;
694}
695
696static int virtio_pci_resume(struct pci_dev *pci_dev)
697{
698 pci_restore_state(pci_dev);
699 pci_set_power_state(pci_dev, PCI_D0);
700 return 0;
701}
702#endif
703
704static struct pci_driver virtio_pci_driver = {
705 .name = "virtio-pci",
706 .id_table = virtio_pci_id_table,
707 .probe = virtio_pci_probe,
Jamie Lokier1f08b832010-01-08 22:01:43 +0000708 .remove = __devexit_p(virtio_pci_remove),
Anthony Liguori33436602007-11-12 21:30:26 -0600709#ifdef CONFIG_PM
710 .suspend = virtio_pci_suspend,
711 .resume = virtio_pci_resume,
712#endif
713};
714
715static int __init virtio_pci_init(void)
716{
717 int err;
718
Mark McLoughlin63d12552008-12-15 12:58:27 +0000719 virtio_pci_root = root_device_register("virtio-pci");
720 if (IS_ERR(virtio_pci_root))
721 return PTR_ERR(virtio_pci_root);
Anthony Liguori33436602007-11-12 21:30:26 -0600722
723 err = pci_register_driver(&virtio_pci_driver);
724 if (err)
Mark McLoughlin4b892e62009-07-07 08:26:45 +0100725 root_device_unregister(virtio_pci_root);
Anthony Liguori33436602007-11-12 21:30:26 -0600726
727 return err;
728}
729
730module_init(virtio_pci_init);
731
732static void __exit virtio_pci_exit(void)
733{
Anthony Liguori33436602007-11-12 21:30:26 -0600734 pci_unregister_driver(&virtio_pci_driver);
Mark McLoughlin63d12552008-12-15 12:58:27 +0000735 root_device_unregister(virtio_pci_root);
Anthony Liguori33436602007-11-12 21:30:26 -0600736}
737
738module_exit(virtio_pci_exit);