projects / deliverable / linux.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
virtio_pci: Use the DMA API if enabled
[deliverable/linux.git] / drivers / virtio / virtio_pci_modern.c
CommitLineData
1fcf0512
MT		 1/*
2 * Virtio PCI driver - modern (virtio 1.0) device support
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 * Copyright Red Hat, Inc. 2014
9 *
10 * Authors:
11 * Anthony Liguori <aliguori@us.ibm.com>
12 * Rusty Russell <rusty@rustcorp.com.au>
13 * Michael S. Tsirkin <mst@redhat.com>
14 *
15 * This work is licensed under the terms of the GNU GPL, version 2 or later.
16 * See the COPYING file in the top-level directory.
17 *
18 */
19
20#define VIRTIO_PCI_NO_LEGACY
21#include "virtio_pci_common.h"
22
c5d4c2c9
MT		 23/*
24 * Type-safe wrappers for io accesses.
25 * Use these to enforce at compile time the following spec requirement:
26 *
27 * The driver MUST access each field using the “natural” access
28 * method, i.e. 32-bit accesses for 32-bit fields, 16-bit accesses
29 * for 16-bit fields and 8-bit accesses for 8-bit fields.
30 */
31static inline u8 vp_ioread8(u8 __iomem *addr)
32{
33 return ioread8(addr);
34}
35static inline u16 vp_ioread16 (u16 __iomem *addr)
36{
37 return ioread16(addr);
38}
39
40static inline u32 vp_ioread32(u32 __iomem *addr)
41{
42 return ioread32(addr);
43}
44
45static inline void vp_iowrite8(u8 value, u8 __iomem *addr)
46{
47 iowrite8(value, addr);
48}
49
50static inline void vp_iowrite16(u16 value, u16 __iomem *addr)
51{
52 iowrite16(value, addr);
53}
54
55static inline void vp_iowrite32(u32 value, u32 __iomem *addr)
56{
57 iowrite32(value, addr);
58}
59
a8557d32
MT		 60static void vp_iowrite64_twopart(u64 val,
61 __le32 __iomem *lo, __le32 __iomem *hi)
62{
63 vp_iowrite32((u32)val, lo);
64 vp_iowrite32(val >> 32, hi);
65}
66
1fcf0512
MT		 67static void __iomem *map_capability(struct pci_dev *dev, int off,
68 size_t minlen,
69 u32 align,
70 u32 start, u32 size,
71 size_t *len)
72{
73 u8 bar;
74 u32 offset, length;
75 void __iomem *p;
76
77 pci_read_config_byte(dev, off + offsetof(struct virtio_pci_cap,
78 bar),
79 &bar);
80 pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, offset),
81 &offset);
82 pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, length),
83 &length);
84
85 if (length <= start) {
86 dev_err(&dev->dev,
87 "virtio_pci: bad capability len %u (>%u expected)\n",
88 length, start);
89 return NULL;
90 }
91
92 if (length - start < minlen) {
93 dev_err(&dev->dev,
94 "virtio_pci: bad capability len %u (>=%zu expected)\n",
95 length, minlen);
96 return NULL;
97 }
98
99 length -= start;
100
101 if (start + offset < offset) {
102 dev_err(&dev->dev,
103 "virtio_pci: map wrap-around %u+%u\n",
104 start, offset);
105 return NULL;
106 }
107
108 offset += start;
109
110 if (offset & (align - 1)) {
111 dev_err(&dev->dev,
112 "virtio_pci: offset %u not aligned to %u\n",
113 offset, align);
114 return NULL;
115 }
116
117 if (length > size)
118 length = size;
119
120 if (len)
121 *len = length;
122
123 if (minlen + offset < minlen ||
124 minlen + offset > pci_resource_len(dev, bar)) {
125 dev_err(&dev->dev,
126 "virtio_pci: map virtio %zu@%u "
127 "out of range on bar %i length %lu\n",
128 minlen, offset,
129 bar, (unsigned long)pci_resource_len(dev, bar));
130 return NULL;
131 }
132
133 p = pci_iomap_range(dev, bar, offset, length);
134 if (!p)
135 dev_err(&dev->dev,
136 "virtio_pci: unable to map virtio %u@%u on bar %i\n",
137 length, offset, bar);
138 return p;
139}
140
1fcf0512
MT		 141/* virtio config->get_features() implementation */
142static u64 vp_get_features(struct virtio_device *vdev)
143{
144 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
145 u64 features;
146
a8557d32
MT		 147 vp_iowrite32(0, &vp_dev->common->device_feature_select);
148 features = vp_ioread32(&vp_dev->common->device_feature);
149 vp_iowrite32(1, &vp_dev->common->device_feature_select);
150 features |= ((u64)vp_ioread32(&vp_dev->common->device_feature) << 32);
1fcf0512
MT		 151
152 return features;
153}
154
155/* virtio config->finalize_features() implementation */
156static int vp_finalize_features(struct virtio_device *vdev)
157{
158 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
159
160 /* Give virtio_ring a chance to accept features. */
161 vring_transport_features(vdev);
162
163 if (!__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
164 dev_err(&vdev->dev, "virtio: device uses modern interface "
165 "but does not have VIRTIO_F_VERSION_1\n");
166 return -EINVAL;
167 }
168
a8557d32
MT		 169 vp_iowrite32(0, &vp_dev->common->guest_feature_select);
170 vp_iowrite32((u32)vdev->features, &vp_dev->common->guest_feature);
171 vp_iowrite32(1, &vp_dev->common->guest_feature_select);
172 vp_iowrite32(vdev->features >> 32, &vp_dev->common->guest_feature);
1fcf0512
MT		 173
174 return 0;
175}
176
177/* virtio config->get() implementation */
178static void vp_get(struct virtio_device *vdev, unsigned offset,
179 void *buf, unsigned len)
180{
181 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
182 u8 b;
183 __le16 w;
184 __le32 l;
185
186 BUG_ON(offset + len > vp_dev->device_len);
187
188 switch (len) {
189 case 1:
190 b = ioread8(vp_dev->device + offset);
191 memcpy(buf, &b, sizeof b);
192 break;
193 case 2:
194 w = cpu_to_le16(ioread16(vp_dev->device + offset));
195 memcpy(buf, &w, sizeof w);
196 break;
197 case 4:
198 l = cpu_to_le32(ioread32(vp_dev->device + offset));
199 memcpy(buf, &l, sizeof l);
200 break;
201 case 8:
202 l = cpu_to_le32(ioread32(vp_dev->device + offset));
203 memcpy(buf, &l, sizeof l);
204 l = cpu_to_le32(ioread32(vp_dev->device + offset + sizeof l));
205 memcpy(buf + sizeof l, &l, sizeof l);
206 break;
207 default:
208 BUG();
209 }
210}
211
212/* the config->set() implementation. it's symmetric to the config->get()
213 * implementation */
214static void vp_set(struct virtio_device *vdev, unsigned offset,
215 const void *buf, unsigned len)
216{
217 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
218 u8 b;
219 __le16 w;
220 __le32 l;
221
222 BUG_ON(offset + len > vp_dev->device_len);
223
224 switch (len) {
225 case 1:
226 memcpy(&b, buf, sizeof b);
227 iowrite8(b, vp_dev->device + offset);
228 break;
229 case 2:
230 memcpy(&w, buf, sizeof w);
231 iowrite16(le16_to_cpu(w), vp_dev->device + offset);
232 break;
233 case 4:
234 memcpy(&l, buf, sizeof l);
235 iowrite32(le32_to_cpu(l), vp_dev->device + offset);
236 break;
237 case 8:
238 memcpy(&l, buf, sizeof l);
239 iowrite32(le32_to_cpu(l), vp_dev->device + offset);
240 memcpy(&l, buf + sizeof l, sizeof l);
241 iowrite32(le32_to_cpu(l), vp_dev->device + offset + sizeof l);
242 break;
243 default:
244 BUG();
245 }
246}
247
248static u32 vp_generation(struct virtio_device *vdev)
249{
250 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
a8557d32 251 return vp_ioread8(&vp_dev->common->config_generation);
1fcf0512
MT		 252}
253
254/* config->{get,set}_status() implementations */
255static u8 vp_get_status(struct virtio_device *vdev)
256{
257 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
a8557d32 258 return vp_ioread8(&vp_dev->common->device_status);
1fcf0512
MT		 259}
260
261static void vp_set_status(struct virtio_device *vdev, u8 status)
262{
263 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
264 /* We should never be setting status to 0. */
265 BUG_ON(status == 0);
a8557d32 266 vp_iowrite8(status, &vp_dev->common->device_status);
1fcf0512
MT		 267}
268
269static void vp_reset(struct virtio_device *vdev)
270{
271 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
272 /* 0 status means a reset. */
a8557d32 273 vp_iowrite8(0, &vp_dev->common->device_status);
1fcf0512
MT		 274 /* Flush out the status write, and flush in device writes,
275 * including MSI-X interrupts, if any. */
a8557d32 276 vp_ioread8(&vp_dev->common->device_status);
1fcf0512
MT		 277 /* Flush pending VQ/configuration callbacks. */
278 vp_synchronize_vectors(vdev);
279}
280
281static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector)
282{
283 /* Setup the vector used for configuration events */
a8557d32 284 vp_iowrite16(vector, &vp_dev->common->msix_config);
1fcf0512
MT		 285 /* Verify we had enough resources to assign the vector */
286 /* Will also flush the write out to device */
a8557d32 287 return vp_ioread16(&vp_dev->common->msix_config);
1fcf0512
MT		 288}
289
1fcf0512
MT		 290static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
291 struct virtio_pci_vq_info *info,
292 unsigned index,
293 void (*callback)(struct virtqueue *vq),
294 const char *name,
295 u16 msix_vec)
296{
297 struct virtio_pci_common_cfg __iomem *cfg = vp_dev->common;
298 struct virtqueue *vq;
299 u16 num, off;
300 int err;
301
a8557d32 302 if (index >= vp_ioread16(&cfg->num_queues))
1fcf0512
MT		 303 return ERR_PTR(-ENOENT);
304
305 /* Select the queue we're interested in */
a8557d32 306 vp_iowrite16(index, &cfg->queue_select);
1fcf0512
MT		 307
308 /* Check if queue is either not available or already active. */
a8557d32
MT		 309 num = vp_ioread16(&cfg->queue_size);
310 if (!num || vp_ioread16(&cfg->queue_enable))
1fcf0512
MT		 311 return ERR_PTR(-ENOENT);
312
313 if (num & (num - 1)) {
314 dev_warn(&vp_dev->pci_dev->dev, "bad queue size %u", num);
315 return ERR_PTR(-EINVAL);
316 }
317
318 /* get offset of notification word for this vq */
a8557d32 319 off = vp_ioread16(&cfg->queue_notify_off);
1fcf0512 320
1fcf0512
MT		 321 info->msix_vector = msix_vec;
322
1fcf0512 323 /* create the vring */
7a5589b2
AL		 324 vq = vring_create_virtqueue(index, num,
325 SMP_CACHE_BYTES, &vp_dev->vdev,
326 true, true, vp_notify, callback, name);
327 if (!vq)
328 return ERR_PTR(-ENOMEM);
1fcf0512
MT		 329
330 /* activate the queue */
7a5589b2
AL		 331 vp_iowrite16(virtqueue_get_vring_size(vq), &cfg->queue_size);
332 vp_iowrite64_twopart(virtqueue_get_desc_addr(vq),
a8557d32 333 &cfg->queue_desc_lo, &cfg->queue_desc_hi);
7a5589b2 334 vp_iowrite64_twopart(virtqueue_get_avail_addr(vq),
a8557d32 335 &cfg->queue_avail_lo, &cfg->queue_avail_hi);
7a5589b2 336 vp_iowrite64_twopart(virtqueue_get_used_addr(vq),
a8557d32 337 &cfg->queue_used_lo, &cfg->queue_used_hi);
1fcf0512 338
3909213c
MT		 339 if (vp_dev->notify_base) {
340 /* offset should not wrap */
341 if ((u64)off * vp_dev->notify_offset_multiplier + 2
342 > vp_dev->notify_len) {
343 dev_warn(&vp_dev->pci_dev->dev,
344 "bad notification offset %u (x %u) "
345 "for queue %u > %zd",
346 off, vp_dev->notify_offset_multiplier,
347 index, vp_dev->notify_len);
348 err = -EINVAL;
349 goto err_map_notify;
350 }
351 vq->priv = (void __force *)vp_dev->notify_base +
352 off * vp_dev->notify_offset_multiplier;
353 } else {
354 vq->priv = (void __force *)map_capability(vp_dev->pci_dev,
355 vp_dev->notify_map_cap, 2, 2,
356 off * vp_dev->notify_offset_multiplier, 2,
357 NULL);
358 }
1fcf0512
MT		 359
360 if (!vq->priv) {
361 err = -ENOMEM;
362 goto err_map_notify;
363 }
364
365 if (msix_vec != VIRTIO_MSI_NO_VECTOR) {
a8557d32
MT		 366 vp_iowrite16(msix_vec, &cfg->queue_msix_vector);
367 msix_vec = vp_ioread16(&cfg->queue_msix_vector);
1fcf0512
MT		 368 if (msix_vec == VIRTIO_MSI_NO_VECTOR) {
369 err = -EBUSY;
370 goto err_assign_vector;
371 }
372 }
373
374 return vq;
375
376err_assign_vector:
3909213c
MT		 377 if (!vp_dev->notify_base)
378 pci_iounmap(vp_dev->pci_dev, (void __iomem __force *)vq->priv);
1fcf0512
MT		 379err_map_notify:
380 vring_del_virtqueue(vq);
1fcf0512
MT		 381 return ERR_PTR(err);
382}
383
384static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned nvqs,
385 struct virtqueue *vqs[],
386 vq_callback_t *callbacks[],
f7ad26ff 387 const char * const names[])
1fcf0512
MT		 388{
389 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
390 struct virtqueue *vq;
391 int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names);
392
393 if (rc)
394 return rc;
395
396 /* Select and activate all queues. Has to be done last: once we do
397 * this, there's no way to go back except reset.
398 */
399 list_for_each_entry(vq, &vdev->vqs, list) {
a8557d32
MT		 400 vp_iowrite16(vq->index, &vp_dev->common->queue_select);
401 vp_iowrite16(1, &vp_dev->common->queue_enable);
1fcf0512
MT		 402 }
403
404 return 0;
405}
406
407static void del_vq(struct virtio_pci_vq_info *info)
408{
409 struct virtqueue *vq = info->vq;
410 struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
411
a8557d32 412 vp_iowrite16(vq->index, &vp_dev->common->queue_select);
1fcf0512
MT		 413
414 if (vp_dev->msix_enabled) {
a8557d32
MT		 415 vp_iowrite16(VIRTIO_MSI_NO_VECTOR,
416 &vp_dev->common->queue_msix_vector);
1fcf0512 417 /* Flush the write out to device */
a8557d32 418 vp_ioread16(&vp_dev->common->queue_msix_vector);
1fcf0512
MT		 419 }
420
3909213c
MT		 421 if (!vp_dev->notify_base)
422 pci_iounmap(vp_dev->pci_dev, (void __force __iomem *)vq->priv);
1fcf0512
MT		 423
424 vring_del_virtqueue(vq);
1fcf0512
MT		 425}
426
d3f5f065
MT		 427static const struct virtio_config_ops virtio_pci_config_nodev_ops = {
428 .get = NULL,
429 .set = NULL,
430 .generation = vp_generation,
431 .get_status = vp_get_status,
432 .set_status = vp_set_status,
433 .reset = vp_reset,
434 .find_vqs = vp_modern_find_vqs,
435 .del_vqs = vp_del_vqs,
436 .get_features = vp_get_features,
437 .finalize_features = vp_finalize_features,
438 .bus_name = vp_bus_name,
439 .set_vq_affinity = vp_set_vq_affinity,
440};
441
1fcf0512
MT		 442static const struct virtio_config_ops virtio_pci_config_ops = {
443 .get = vp_get,
444 .set = vp_set,
445 .generation = vp_generation,
446 .get_status = vp_get_status,
447 .set_status = vp_set_status,
448 .reset = vp_reset,
449 .find_vqs = vp_modern_find_vqs,
450 .del_vqs = vp_del_vqs,
451 .get_features = vp_get_features,
452 .finalize_features = vp_finalize_features,
453 .bus_name = vp_bus_name,
454 .set_vq_affinity = vp_set_vq_affinity,
455};
456
457/**
458 * virtio_pci_find_capability - walk capabilities to find device info.
459 * @dev: the pci device
460 * @cfg_type: the VIRTIO_PCI_CAP_* value we seek
461 * @ioresource_types: IORESOURCE_MEM and/or IORESOURCE_IO.
462 *
463 * Returns offset of the capability, or 0.
464 */
465static inline int virtio_pci_find_capability(struct pci_dev *dev, u8 cfg_type,
59a5b0f7 466 u32 ioresource_types, int *bars)
1fcf0512
MT		 467{
468 int pos;
469
470 for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR);
471 pos > 0;
472 pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) {
473 u8 type, bar;
474 pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap,
475 cfg_type),
476 &type);
477 pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap,
478 bar),
479 &bar);
480
481 /* Ignore structures with reserved BAR values */
482 if (bar > 0x5)
483 continue;
484
485 if (type == cfg_type) {
486 if (pci_resource_len(dev, bar) &&
59a5b0f7
GH		 487 pci_resource_flags(dev, bar) & ioresource_types) {
488 *bars |= (1 << bar);
1fcf0512 489 return pos;
59a5b0f7 490 }
1fcf0512
MT		 491 }
492 }
493 return 0;
494}
495
89461c4a 496/* This is part of the ABI. Don't screw with it. */
1fcf0512
MT		 497static inline void check_offsets(void)
498{
89461c4a
RR		 499 /* Note: disk space was harmed in compilation of this function. */
500 BUILD_BUG_ON(VIRTIO_PCI_CAP_VNDR !=
501 offsetof(struct virtio_pci_cap, cap_vndr));
502 BUILD_BUG_ON(VIRTIO_PCI_CAP_NEXT !=
503 offsetof(struct virtio_pci_cap, cap_next));
504 BUILD_BUG_ON(VIRTIO_PCI_CAP_LEN !=
505 offsetof(struct virtio_pci_cap, cap_len));
506 BUILD_BUG_ON(VIRTIO_PCI_CAP_CFG_TYPE !=
507 offsetof(struct virtio_pci_cap, cfg_type));
508 BUILD_BUG_ON(VIRTIO_PCI_CAP_BAR !=
509 offsetof(struct virtio_pci_cap, bar));
510 BUILD_BUG_ON(VIRTIO_PCI_CAP_OFFSET !=
511 offsetof(struct virtio_pci_cap, offset));
512 BUILD_BUG_ON(VIRTIO_PCI_CAP_LENGTH !=
513 offsetof(struct virtio_pci_cap, length));
514 BUILD_BUG_ON(VIRTIO_PCI_NOTIFY_CAP_MULT !=
515 offsetof(struct virtio_pci_notify_cap,
516 notify_off_multiplier));
517 BUILD_BUG_ON(VIRTIO_PCI_COMMON_DFSELECT !=
518 offsetof(struct virtio_pci_common_cfg,
519 device_feature_select));
520 BUILD_BUG_ON(VIRTIO_PCI_COMMON_DF !=
521 offsetof(struct virtio_pci_common_cfg, device_feature));
522 BUILD_BUG_ON(VIRTIO_PCI_COMMON_GFSELECT !=
523 offsetof(struct virtio_pci_common_cfg,
524 guest_feature_select));
525 BUILD_BUG_ON(VIRTIO_PCI_COMMON_GF !=
526 offsetof(struct virtio_pci_common_cfg, guest_feature));
527 BUILD_BUG_ON(VIRTIO_PCI_COMMON_MSIX !=
528 offsetof(struct virtio_pci_common_cfg, msix_config));
529 BUILD_BUG_ON(VIRTIO_PCI_COMMON_NUMQ !=
530 offsetof(struct virtio_pci_common_cfg, num_queues));
531 BUILD_BUG_ON(VIRTIO_PCI_COMMON_STATUS !=
532 offsetof(struct virtio_pci_common_cfg, device_status));
533 BUILD_BUG_ON(VIRTIO_PCI_COMMON_CFGGENERATION !=
534 offsetof(struct virtio_pci_common_cfg, config_generation));
535 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SELECT !=
536 offsetof(struct virtio_pci_common_cfg, queue_select));
537 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SIZE !=
538 offsetof(struct virtio_pci_common_cfg, queue_size));
539 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_MSIX !=
540 offsetof(struct virtio_pci_common_cfg, queue_msix_vector));
541 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_ENABLE !=
542 offsetof(struct virtio_pci_common_cfg, queue_enable));
543 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NOFF !=
544 offsetof(struct virtio_pci_common_cfg, queue_notify_off));
545 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCLO !=
546 offsetof(struct virtio_pci_common_cfg, queue_desc_lo));
547 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCHI !=
548 offsetof(struct virtio_pci_common_cfg, queue_desc_hi));
549 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILLO !=
550 offsetof(struct virtio_pci_common_cfg, queue_avail_lo));
551 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILHI !=
552 offsetof(struct virtio_pci_common_cfg, queue_avail_hi));
553 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDLO !=
554 offsetof(struct virtio_pci_common_cfg, queue_used_lo));
555 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDHI !=
556 offsetof(struct virtio_pci_common_cfg, queue_used_hi));
1fcf0512
MT		 557}
558
559/* the PCI probing function */
560int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
561{
562 struct pci_dev *pci_dev = vp_dev->pci_dev;
563 int err, common, isr, notify, device;
564 u32 notify_length;
3909213c 565 u32 notify_offset;
1fcf0512
MT		 566
567 check_offsets();
568
569 /* We only own devices >= 0x1000 and <= 0x107f: leave the rest. */
570 if (pci_dev->device < 0x1000 || pci_dev->device > 0x107f)
571 return -ENODEV;
572
573 if (pci_dev->device < 0x1040) {
574 /* Transitional devices: use the PCI subsystem device id as
575 * virtio device id, same as legacy driver always did.
576 */
577 vp_dev->vdev.id.device = pci_dev->subsystem_device;
578 } else {
579 /* Modern devices: simply use PCI device id, but start from 0x1040. */
580 vp_dev->vdev.id.device = pci_dev->device - 0x1040;
581 }
582 vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
583
1fcf0512
MT		 584 /* check for a common config: if not, use legacy mode (bar 0). */
585 common = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG,
59a5b0f7
GH		 586 IORESOURCE_IO | IORESOURCE_MEM,
587 &vp_dev->modern_bars);
1fcf0512
MT		 588 if (!common) {
589 dev_info(&pci_dev->dev,
590 "virtio_pci: leaving for legacy driver\n");
591 return -ENODEV;
592 }
593
594 /* If common is there, these should be too... */
595 isr = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_ISR_CFG,
59a5b0f7
GH		 596 IORESOURCE_IO | IORESOURCE_MEM,
597 &vp_dev->modern_bars);
1fcf0512 598 notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG,
59a5b0f7
GH		 599 IORESOURCE_IO | IORESOURCE_MEM,
600 &vp_dev->modern_bars);
1fcf0512
MT		 601 if (!isr || !notify) {
602 dev_err(&pci_dev->dev,
603 "virtio_pci: missing capabilities %i/%i/%i\n",
604 common, isr, notify);
605 return -EINVAL;
606 }
607
7a5589b2
AL		 608 err = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(64));
609 if (err)
610 err = dma_set_mask_and_coherent(&pci_dev->dev,
611 DMA_BIT_MASK(32));
612 if (err)
613 dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n");
614
1fcf0512
MT		 615 /* Device capability is only mandatory for devices that have
616 * device-specific configuration.
617 */
618 device = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG,
59a5b0f7
GH		 619 IORESOURCE_IO | IORESOURCE_MEM,
620 &vp_dev->modern_bars);
621
622 err = pci_request_selected_regions(pci_dev, vp_dev->modern_bars,
623 "virtio-pci-modern");
624 if (err)
625 return err;
1fcf0512
MT		 626
627 err = -EINVAL;
628 vp_dev->common = map_capability(pci_dev, common,
629 sizeof(struct virtio_pci_common_cfg), 4,
630 0, sizeof(struct virtio_pci_common_cfg),
631 NULL);
632 if (!vp_dev->common)
633 goto err_map_common;
634 vp_dev->isr = map_capability(pci_dev, isr, sizeof(u8), 1,
635 0, 1,
636 NULL);
637 if (!vp_dev->isr)
638 goto err_map_isr;
639
640 /* Read notify_off_multiplier from config space. */
641 pci_read_config_dword(pci_dev,
642 notify + offsetof(struct virtio_pci_notify_cap,
643 notify_off_multiplier),
644 &vp_dev->notify_offset_multiplier);
3909213c 645 /* Read notify length and offset from config space. */
1fcf0512
MT		 646 pci_read_config_dword(pci_dev,
647 notify + offsetof(struct virtio_pci_notify_cap,
648 cap.length),
649 &notify_length);
650
3909213c
MT		 651 pci_read_config_dword(pci_dev,
652 notify + offsetof(struct virtio_pci_notify_cap,
4e94ebdd 653 cap.offset),
3909213c
MT		 654 &notify_offset);
655
656 /* We don't know how many VQs we'll map, ahead of the time.
657 * If notify length is small, map it all now.
658 * Otherwise, map each VQ individually later.
659 */
660 if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) {
661 vp_dev->notify_base = map_capability(pci_dev, notify, 2, 2,
662 0, notify_length,
663 &vp_dev->notify_len);
664 if (!vp_dev->notify_base)
665 goto err_map_notify;
666 } else {
667 vp_dev->notify_map_cap = notify;
668 }
1fcf0512
MT		 669
670 /* Again, we don't know how much we should map, but PAGE_SIZE
671 * is more than enough for all existing devices.
672 */
673 if (device) {
674 vp_dev->device = map_capability(pci_dev, device, 0, 4,
675 0, PAGE_SIZE,
676 &vp_dev->device_len);
677 if (!vp_dev->device)
678 goto err_map_device;
1fcf0512 679
d3f5f065
MT		 680 vp_dev->vdev.config = &virtio_pci_config_ops;
681 } else {
682 vp_dev->vdev.config = &virtio_pci_config_nodev_ops;
683 }
1fcf0512
MT		 684
685 vp_dev->config_vector = vp_config_vector;
686 vp_dev->setup_vq = setup_vq;
687 vp_dev->del_vq = del_vq;
688
689 return 0;
690
691err_map_device:
3909213c
MT		 692 if (vp_dev->notify_base)
693 pci_iounmap(pci_dev, vp_dev->notify_base);
694err_map_notify:
1fcf0512
MT		 695 pci_iounmap(pci_dev, vp_dev->isr);
696err_map_isr:
697 pci_iounmap(pci_dev, vp_dev->common);
698err_map_common:
699 return err;
700}
701
702void virtio_pci_modern_remove(struct virtio_pci_device *vp_dev)
703{
704 struct pci_dev *pci_dev = vp_dev->pci_dev;
705
706 if (vp_dev->device)
707 pci_iounmap(pci_dev, vp_dev->device);
3909213c
MT		 708 if (vp_dev->notify_base)
709 pci_iounmap(pci_dev, vp_dev->notify_base);
1fcf0512
MT		 710 pci_iounmap(pci_dev, vp_dev->isr);
711 pci_iounmap(pci_dev, vp_dev->common);
59a5b0f7 712 pci_release_selected_regions(pci_dev, vp_dev->modern_bars);
1fcf0512 713}
Linux kernel - Deliverables
This page took 0.108386 seconds and 5 git commands to generate.