Commit | Line | Data |
---|---|---|
3343660d AL |
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> | |
5a0e3ad6 | 20 | #include <linux/slab.h> |
3343660d AL |
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 | ||
29 | MODULE_AUTHOR("Anthony Liguori <aliguori@us.ibm.com>"); | |
30 | MODULE_DESCRIPTION("virtio-pci"); | |
31 | MODULE_LICENSE("GPL"); | |
32 | MODULE_VERSION("1"); | |
33 | ||
34 | /* Our device structure */ | |
35 | struct 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 */ | |
97968358 | 41 | void __iomem *ioaddr; |
3343660d AL |
42 | |
43 | /* a list of queues so we can dispatch IRQs */ | |
44 | spinlock_t lock; | |
45 | struct list_head virtqueues; | |
82af8ce8 MT |
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; | |
e969fed5 | 56 | /* Vectors allocated, excluding per-vq vectors if any */ |
82af8ce8 | 57 | unsigned msix_used_vectors; |
e969fed5 MT |
58 | /* Whether we have vector per vq */ |
59 | bool per_vq_vectors; | |
82af8ce8 MT |
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. */ | |
65 | enum { | |
66 | VP_MSIX_CONFIG_VECTOR = 0, | |
67 | VP_MSIX_VQ_VECTOR = 1, | |
3343660d AL |
68 | }; |
69 | ||
70 | struct 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; | |
82af8ce8 MT |
86 | |
87 | /* MSI-X vector (or none) */ | |
f68d2408 | 88 | unsigned msix_vector; |
3343660d AL |
89 | }; |
90 | ||
91 | /* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */ | |
92 | static 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 | ||
97 | MODULE_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. */ | |
63d12556 | 102 | static struct device *virtio_pci_root; |
3343660d | 103 | |
3343660d AL |
104 | /* Convert a generic virtio device to our structure */ |
105 | static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev) | |
106 | { | |
107 | return container_of(vdev, struct virtio_pci_device, vdev); | |
108 | } | |
109 | ||
c45a6816 RR |
110 | /* virtio config->get_features() implementation */ |
111 | static u32 vp_get_features(struct virtio_device *vdev) | |
112 | { | |
113 | struct virtio_pci_device *vp_dev = to_vp_device(vdev); | |
114 | ||
115 | /* 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 | } | |
119 | ||
c624896e RR |
120 | /* virtio config->finalize_features() implementation */ |
121 | static void vp_finalize_features(struct virtio_device *vdev) | |
3343660d AL |
122 | { |
123 | struct virtio_pci_device *vp_dev = to_vp_device(vdev); | |
3343660d | 124 | |
e34f8725 RR |
125 | /* Give virtio_ring a chance to accept features. */ |
126 | vring_transport_features(vdev); | |
127 | ||
c624896e RR |
128 | /* 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); | |
3343660d AL |
131 | } |
132 | ||
133 | /* virtio config->get() implementation */ | |
134 | static 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); | |
82af8ce8 MT |
138 | void __iomem *ioaddr = vp_dev->ioaddr + |
139 | VIRTIO_PCI_CONFIG(vp_dev) + offset; | |
3343660d AL |
140 | 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 */ | |
149 | static 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); | |
82af8ce8 MT |
153 | void __iomem *ioaddr = vp_dev->ioaddr + |
154 | VIRTIO_PCI_CONFIG(vp_dev) + offset; | |
3343660d AL |
155 | 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 */ | |
163 | static 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 | ||
169 | static 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); | |
597d56e4 | 174 | iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS); |
3343660d AL |
175 | } |
176 | ||
177 | static 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. */ | |
597d56e4 | 181 | iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS); |
3343660d AL |
182 | } |
183 | ||
184 | /* the notify function used when creating a virt queue */ | |
185 | static 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 | ||
77cf5246 MT |
195 | /* Handle a configuration change: Tell driver if it wants to know. */ |
196 | static 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. */ | |
209 | static 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 | ||
3343660d AL |
226 | /* 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. */ | |
232 | static irqreturn_t vp_interrupt(int irq, void *opaque) | |
233 | { | |
234 | struct virtio_pci_device *vp_dev = opaque; | |
3343660d AL |
235 | 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. */ | |
77cf5246 MT |
246 | if (isr & VIRTIO_PCI_ISR_CONFIG) |
247 | vp_config_changed(irq, opaque); | |
3343660d | 248 | |
77cf5246 | 249 | return vp_vring_interrupt(irq, opaque); |
3343660d AL |
250 | } |
251 | ||
82af8ce8 MT |
252 | static 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); | |
82af8ce8 MT |
264 | |
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 | ||
82af8ce8 | 272 | pci_disable_msix(vp_dev->pci_dev); |
ff52c3fc MT |
273 | vp_dev->msix_enabled = 0; |
274 | vp_dev->msix_vectors = 0; | |
82af8ce8 | 275 | } |
ff52c3fc MT |
276 | |
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; | |
82af8ce8 MT |
282 | } |
283 | ||
f68d2408 RR |
284 | static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors, |
285 | bool per_vq_vectors) | |
82af8ce8 MT |
286 | { |
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; | |
e969fed5 | 291 | |
82af8ce8 MT |
292 | vp_dev->msix_entries = kmalloc(nvectors * sizeof *vp_dev->msix_entries, |
293 | GFP_KERNEL); | |
294 | if (!vp_dev->msix_entries) | |
ff52c3fc | 295 | goto error; |
82af8ce8 MT |
296 | vp_dev->msix_names = kmalloc(nvectors * sizeof *vp_dev->msix_names, |
297 | GFP_KERNEL); | |
298 | if (!vp_dev->msix_names) | |
ff52c3fc | 299 | goto error; |
82af8ce8 MT |
300 | |
301 | for (i = 0; i < nvectors; ++i) | |
302 | vp_dev->msix_entries[i].entry = i; | |
303 | ||
f68d2408 | 304 | /* pci_enable_msix returns positive if we can't get this many. */ |
e969fed5 MT |
305 | 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; | |
312 | ||
313 | /* 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; | |
82af8ce8 | 323 | |
e969fed5 MT |
324 | 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; | |
82af8ce8 MT |
330 | } |
331 | ||
e969fed5 | 332 | if (!per_vq_vectors) { |
82af8ce8 MT |
333 | /* 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) | |
ff52c3fc | 341 | goto error; |
82af8ce8 MT |
342 | ++vp_dev->msix_used_vectors; |
343 | } | |
344 | return 0; | |
ff52c3fc | 345 | error: |
82af8ce8 | 346 | vp_free_vectors(vdev); |
82af8ce8 MT |
347 | return err; |
348 | } | |
349 | ||
f68d2408 RR |
350 | static 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 | ||
362 | static struct virtqueue *setup_vq(struct virtio_device *vdev, unsigned index, | |
363 | void (*callback)(struct virtqueue *vq), | |
364 | const char *name, | |
365 | u16 msix_vec) | |
3343660d AL |
366 | { |
367 | struct virtio_pci_device *vp_dev = to_vp_device(vdev); | |
368 | struct virtio_pci_vq_info *info; | |
369 | struct virtqueue *vq; | |
13b1eb33 | 370 | unsigned long flags, size; |
e969fed5 | 371 | u16 num; |
3343660d AL |
372 | 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; | |
f68d2408 | 390 | info->msix_vector = msix_vec; |
3343660d | 391 | |
498af147 | 392 | size = PAGE_ALIGN(vring_size(num, VIRTIO_PCI_VRING_ALIGN)); |
13b1eb33 | 393 | info->queue = alloc_pages_exact(size, GFP_KERNEL|__GFP_ZERO); |
3343660d AL |
394 | if (info->queue == NULL) { |
395 | err = -ENOMEM; | |
396 | goto out_info; | |
397 | } | |
398 | ||
399 | /* activate the queue */ | |
480daab4 | 400 | iowrite32(virt_to_phys(info->queue) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT, |
3343660d AL |
401 | vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); |
402 | ||
403 | /* create the vring */ | |
87c7d57c | 404 | vq = vring_new_virtqueue(info->num, VIRTIO_PCI_VRING_ALIGN, |
9499f5e7 | 405 | vdev, info->queue, vp_notify, callback, name); |
3343660d AL |
406 | if (!vq) { |
407 | err = -ENOMEM; | |
408 | goto out_activate_queue; | |
409 | } | |
410 | ||
411 | vq->priv = info; | |
412 | info->vq = vq; | |
413 | ||
f68d2408 RR |
414 | 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) { | |
82af8ce8 MT |
418 | err = -EBUSY; |
419 | goto out_assign; | |
420 | } | |
421 | } | |
422 | ||
27ebe308 | 423 | spin_lock_irqsave(&vp_dev->lock, flags); |
3343660d | 424 | list_add(&info->node, &vp_dev->virtqueues); |
27ebe308 | 425 | spin_unlock_irqrestore(&vp_dev->lock, flags); |
3343660d AL |
426 | |
427 | return vq; | |
428 | ||
82af8ce8 | 429 | out_assign: |
82af8ce8 | 430 | vring_del_virtqueue(vq); |
3343660d AL |
431 | out_activate_queue: |
432 | iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); | |
13b1eb33 | 433 | free_pages_exact(info->queue, size); |
3343660d AL |
434 | out_info: |
435 | kfree(info); | |
436 | return ERR_PTR(err); | |
437 | } | |
438 | ||
3343660d AL |
439 | static 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; | |
f6c82507 MT |
443 | 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); | |
3343660d | 448 | |
82af8ce8 MT |
449 | iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL); |
450 | ||
82af8ce8 MT |
451 | 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 | ||
3343660d AL |
458 | vring_del_virtqueue(vq); |
459 | ||
460 | /* Select and deactivate the queue */ | |
3343660d AL |
461 | iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); |
462 | ||
498af147 | 463 | size = PAGE_ALIGN(vring_size(info->num, VIRTIO_PCI_VRING_ALIGN)); |
13b1eb33 | 464 | free_pages_exact(info->queue, size); |
3343660d AL |
465 | kfree(info); |
466 | } | |
467 | ||
82af8ce8 | 468 | /* the config->del_vqs() implementation */ |
d2a7ddda MT |
469 | static void vp_del_vqs(struct virtio_device *vdev) |
470 | { | |
e969fed5 | 471 | struct virtio_pci_device *vp_dev = to_vp_device(vdev); |
d2a7ddda | 472 | struct virtqueue *vq, *n; |
e969fed5 | 473 | struct virtio_pci_vq_info *info; |
d2a7ddda | 474 | |
e969fed5 MT |
475 | list_for_each_entry_safe(vq, n, &vdev->vqs, list) { |
476 | info = vq->priv; | |
31198159 MT |
477 | if (vp_dev->per_vq_vectors && |
478 | info->msix_vector != VIRTIO_MSI_NO_VECTOR) | |
f68d2408 RR |
479 | free_irq(vp_dev->msix_entries[info->msix_vector].vector, |
480 | vq); | |
d2a7ddda | 481 | vp_del_vq(vq); |
e969fed5 MT |
482 | } |
483 | vp_dev->per_vq_vectors = false; | |
82af8ce8 MT |
484 | |
485 | vp_free_vectors(vdev); | |
d2a7ddda MT |
486 | } |
487 | ||
e969fed5 MT |
488 | static 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[], | |
f68d2408 | 492 | bool use_msix, |
e969fed5 | 493 | bool per_vq_vectors) |
d2a7ddda | 494 | { |
e969fed5 | 495 | struct virtio_pci_device *vp_dev = to_vp_device(vdev); |
f68d2408 RR |
496 | u16 msix_vec; |
497 | int i, err, nvectors, allocated_vectors; | |
82af8ce8 | 498 | |
f68d2408 RR |
499 | 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 | } | |
d2a7ddda | 520 | |
e969fed5 MT |
521 | vp_dev->per_vq_vectors = per_vq_vectors; |
522 | allocated_vectors = vp_dev->msix_used_vectors; | |
d2a7ddda | 523 | for (i = 0; i < nvqs; ++i) { |
e969fed5 | 524 | if (!callbacks[i] || !vp_dev->msix_enabled) |
f68d2408 | 525 | msix_vec = VIRTIO_MSI_NO_VECTOR; |
e969fed5 | 526 | else if (vp_dev->per_vq_vectors) |
f68d2408 | 527 | msix_vec = allocated_vectors++; |
e969fed5 | 528 | else |
f68d2408 RR |
529 | msix_vec = VP_MSIX_VQ_VECTOR; |
530 | vqs[i] = setup_vq(vdev, i, callbacks[i], names[i], msix_vec); | |
e969fed5 MT |
531 | if (IS_ERR(vqs[i])) { |
532 | err = PTR_ERR(vqs[i]); | |
82af8ce8 | 533 | goto error_find; |
e969fed5 | 534 | } |
0b22bd0b MT |
535 | |
536 | if (!vp_dev->per_vq_vectors || msix_vec == VIRTIO_MSI_NO_VECTOR) | |
537 | continue; | |
538 | ||
e969fed5 | 539 | /* allocate per-vq irq if available and necessary */ |
0b22bd0b MT |
540 | 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; | |
e969fed5 | 551 | } |
d2a7ddda MT |
552 | } |
553 | return 0; | |
554 | ||
82af8ce8 | 555 | error_find: |
d2a7ddda | 556 | vp_del_vqs(vdev); |
82af8ce8 MT |
557 | |
558 | error_request: | |
e969fed5 MT |
559 | return err; |
560 | } | |
561 | ||
562 | /* the config->find_vqs() implementation */ | |
563 | static int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs, | |
564 | struct virtqueue *vqs[], | |
565 | vq_callback_t *callbacks[], | |
566 | const char *names[]) | |
567 | { | |
f68d2408 | 568 | int err; |
e969fed5 | 569 | |
f68d2408 RR |
570 | /* Try MSI-X with one vector per queue. */ |
571 | err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, true, true); | |
e969fed5 MT |
572 | if (!err) |
573 | return 0; | |
f68d2408 | 574 | /* Fallback: MSI-X with one vector for config, one shared for queues. */ |
e969fed5 | 575 | err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, |
f68d2408 | 576 | true, false); |
e969fed5 MT |
577 | if (!err) |
578 | return 0; | |
579 | /* Finally fall back to regular interrupts. */ | |
f68d2408 RR |
580 | return vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, |
581 | false, false); | |
d2a7ddda MT |
582 | } |
583 | ||
3343660d | 584 | static struct virtio_config_ops virtio_pci_config_ops = { |
3343660d AL |
585 | .get = vp_get, |
586 | .set = vp_set, | |
587 | .get_status = vp_get_status, | |
588 | .set_status = vp_set_status, | |
589 | .reset = vp_reset, | |
d2a7ddda MT |
590 | .find_vqs = vp_find_vqs, |
591 | .del_vqs = vp_del_vqs, | |
c45a6816 | 592 | .get_features = vp_get_features, |
c624896e | 593 | .finalize_features = vp_finalize_features, |
3343660d AL |
594 | }; |
595 | ||
29f9f12e MM |
596 | static 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 | ||
82af8ce8 | 602 | vp_del_vqs(dev); |
29f9f12e MM |
603 | 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 | ||
3343660d AL |
610 | /* the PCI probing function */ |
611 | static 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 | ||
55a7c066 AL |
621 | 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 | ||
3343660d AL |
627 | /* 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 | ||
63d12556 | 632 | vp_dev->vdev.dev.parent = virtio_pci_root; |
29f9f12e | 633 | vp_dev->vdev.dev.release = virtio_pci_release_dev; |
3343660d AL |
634 | 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); | |
bc505f37 | 653 | pci_set_master(pci_dev); |
3343660d AL |
654 | |
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 | |
88393161 | 658 | * the subsystem ids */ |
3343660d AL |
659 | vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor; |
660 | vp_dev->vdev.id.device = pci_dev->subsystem_device; | |
661 | ||
3343660d AL |
662 | /* finally register the virtio device */ |
663 | err = register_virtio_device(&vp_dev->vdev); | |
664 | if (err) | |
82af8ce8 | 665 | goto out_set_drvdata; |
3343660d AL |
666 | |
667 | return 0; | |
668 | ||
3343660d AL |
669 | out_set_drvdata: |
670 | pci_set_drvdata(pci_dev, NULL); | |
671 | pci_iounmap(pci_dev, vp_dev->ioaddr); | |
672 | out_req_regions: | |
673 | pci_release_regions(pci_dev); | |
674 | out_enable_device: | |
675 | pci_disable_device(pci_dev); | |
676 | out: | |
677 | kfree(vp_dev); | |
678 | return err; | |
679 | } | |
680 | ||
681 | static void __devexit virtio_pci_remove(struct pci_dev *pci_dev) | |
682 | { | |
683 | struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); | |
684 | ||
bd6c2690 | 685 | unregister_virtio_device(&vp_dev->vdev); |
3343660d AL |
686 | } |
687 | ||
688 | #ifdef CONFIG_PM | |
689 | static 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 | ||
696 | static 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 | ||
704 | static struct pci_driver virtio_pci_driver = { | |
705 | .name = "virtio-pci", | |
706 | .id_table = virtio_pci_id_table, | |
707 | .probe = virtio_pci_probe, | |
1f08b833 | 708 | .remove = __devexit_p(virtio_pci_remove), |
3343660d AL |
709 | #ifdef CONFIG_PM |
710 | .suspend = virtio_pci_suspend, | |
711 | .resume = virtio_pci_resume, | |
712 | #endif | |
713 | }; | |
714 | ||
715 | static int __init virtio_pci_init(void) | |
716 | { | |
717 | int err; | |
718 | ||
63d12556 MM |
719 | virtio_pci_root = root_device_register("virtio-pci"); |
720 | if (IS_ERR(virtio_pci_root)) | |
721 | return PTR_ERR(virtio_pci_root); | |
3343660d AL |
722 | |
723 | err = pci_register_driver(&virtio_pci_driver); | |
724 | if (err) | |
4b892e65 | 725 | root_device_unregister(virtio_pci_root); |
3343660d AL |
726 | |
727 | return err; | |
728 | } | |
729 | ||
730 | module_init(virtio_pci_init); | |
731 | ||
732 | static void __exit virtio_pci_exit(void) | |
733 | { | |
3343660d | 734 | pci_unregister_driver(&virtio_pci_driver); |
63d12556 | 735 | root_device_unregister(virtio_pci_root); |
3343660d AL |
736 | } |
737 | ||
738 | module_exit(virtio_pci_exit); |