1 // SPDX-License-Identifier: GPL-2.0-or-later
2
3 #include <linux/virtio_pci_modern.h>
4 #include <linux/module.h>
5 #include <linux/pci.h>
6
7 /*
8 * vp_modern_map_capability - map a part of virtio pci capability
9 * @mdev: the modern virtio-pci device
10 * @off: offset of the capability
11 * @minlen: minimal length of the capability
12 * @align: align requirement
13 * @start: start from the capability
14 * @size: map size
15 * @len: the length that is actually mapped
16 * @pa: physical address of the capability
17 *
18 * Returns the io address of for the part of the capability
19 */
20 static void __iomem *
vp_modern_map_capability(struct virtio_pci_modern_device * mdev,int off,size_t minlen,u32 align,u32 start,u32 size,size_t * len,resource_size_t * pa)21 vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
22 size_t minlen, u32 align, u32 start, u32 size,
23 size_t *len, resource_size_t *pa)
24 {
25 struct pci_dev *dev = mdev->pci_dev;
26 u8 bar;
27 u32 offset, length;
28 void __iomem *p;
29
30 pci_read_config_byte(dev, off + offsetof(struct virtio_pci_cap,
31 bar),
32 &bar);
33 pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, offset),
34 &offset);
35 pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, length),
36 &length);
37
38 /* Check if the BAR may have changed since we requested the region. */
39 if (bar >= PCI_STD_NUM_BARS || !(mdev->modern_bars & (1 << bar))) {
40 dev_err(&dev->dev,
41 "virtio_pci: bar unexpectedly changed to %u\n", bar);
42 return NULL;
43 }
44
45 if (length <= start) {
46 dev_err(&dev->dev,
47 "virtio_pci: bad capability len %u (>%u expected)\n",
48 length, start);
49 return NULL;
50 }
51
52 if (length - start < minlen) {
53 dev_err(&dev->dev,
54 "virtio_pci: bad capability len %u (>=%zu expected)\n",
55 length, minlen);
56 return NULL;
57 }
58
59 length -= start;
60
61 if (start + offset < offset) {
62 dev_err(&dev->dev,
63 "virtio_pci: map wrap-around %u+%u\n",
64 start, offset);
65 return NULL;
66 }
67
68 offset += start;
69
70 if (offset & (align - 1)) {
71 dev_err(&dev->dev,
72 "virtio_pci: offset %u not aligned to %u\n",
73 offset, align);
74 return NULL;
75 }
76
77 if (length > size)
78 length = size;
79
80 if (len)
81 *len = length;
82
83 if (minlen + offset < minlen ||
84 minlen + offset > pci_resource_len(dev, bar)) {
85 dev_err(&dev->dev,
86 "virtio_pci: map virtio %zu@%u "
87 "out of range on bar %i length %lu\n",
88 minlen, offset,
89 bar, (unsigned long)pci_resource_len(dev, bar));
90 return NULL;
91 }
92
93 p = pci_iomap_range(dev, bar, offset, length);
94 if (!p)
95 dev_err(&dev->dev,
96 "virtio_pci: unable to map virtio %u@%u on bar %i\n",
97 length, offset, bar);
98 else if (pa)
99 *pa = pci_resource_start(dev, bar) + offset;
100
101 return p;
102 }
103
104 /**
105 * virtio_pci_find_capability - walk capabilities to find device info.
106 * @dev: the pci device
107 * @cfg_type: the VIRTIO_PCI_CAP_* value we seek
108 * @ioresource_types: IORESOURCE_MEM and/or IORESOURCE_IO.
109 * @bars: the bitmask of BARs
110 *
111 * Returns offset of the capability, or 0.
112 */
virtio_pci_find_capability(struct pci_dev * dev,u8 cfg_type,u32 ioresource_types,int * bars)113 static inline int virtio_pci_find_capability(struct pci_dev *dev, u8 cfg_type,
114 u32 ioresource_types, int *bars)
115 {
116 int pos;
117
118 for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR);
119 pos > 0;
120 pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) {
121 u8 type, bar;
122 pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap,
123 cfg_type),
124 &type);
125 pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap,
126 bar),
127 &bar);
128
129 /* Ignore structures with reserved BAR values */
130 if (bar >= PCI_STD_NUM_BARS)
131 continue;
132
133 if (type == cfg_type) {
134 if (pci_resource_len(dev, bar) &&
135 pci_resource_flags(dev, bar) & ioresource_types) {
136 *bars |= (1 << bar);
137 return pos;
138 }
139 }
140 }
141 return 0;
142 }
143
144 /* This is part of the ABI. Don't screw with it. */
check_offsets(void)145 static inline void check_offsets(void)
146 {
147 /* Note: disk space was harmed in compilation of this function. */
148 BUILD_BUG_ON(VIRTIO_PCI_CAP_VNDR !=
149 offsetof(struct virtio_pci_cap, cap_vndr));
150 BUILD_BUG_ON(VIRTIO_PCI_CAP_NEXT !=
151 offsetof(struct virtio_pci_cap, cap_next));
152 BUILD_BUG_ON(VIRTIO_PCI_CAP_LEN !=
153 offsetof(struct virtio_pci_cap, cap_len));
154 BUILD_BUG_ON(VIRTIO_PCI_CAP_CFG_TYPE !=
155 offsetof(struct virtio_pci_cap, cfg_type));
156 BUILD_BUG_ON(VIRTIO_PCI_CAP_BAR !=
157 offsetof(struct virtio_pci_cap, bar));
158 BUILD_BUG_ON(VIRTIO_PCI_CAP_OFFSET !=
159 offsetof(struct virtio_pci_cap, offset));
160 BUILD_BUG_ON(VIRTIO_PCI_CAP_LENGTH !=
161 offsetof(struct virtio_pci_cap, length));
162 BUILD_BUG_ON(VIRTIO_PCI_NOTIFY_CAP_MULT !=
163 offsetof(struct virtio_pci_notify_cap,
164 notify_off_multiplier));
165 BUILD_BUG_ON(VIRTIO_PCI_COMMON_DFSELECT !=
166 offsetof(struct virtio_pci_common_cfg,
167 device_feature_select));
168 BUILD_BUG_ON(VIRTIO_PCI_COMMON_DF !=
169 offsetof(struct virtio_pci_common_cfg, device_feature));
170 BUILD_BUG_ON(VIRTIO_PCI_COMMON_GFSELECT !=
171 offsetof(struct virtio_pci_common_cfg,
172 guest_feature_select));
173 BUILD_BUG_ON(VIRTIO_PCI_COMMON_GF !=
174 offsetof(struct virtio_pci_common_cfg, guest_feature));
175 BUILD_BUG_ON(VIRTIO_PCI_COMMON_MSIX !=
176 offsetof(struct virtio_pci_common_cfg, msix_config));
177 BUILD_BUG_ON(VIRTIO_PCI_COMMON_NUMQ !=
178 offsetof(struct virtio_pci_common_cfg, num_queues));
179 BUILD_BUG_ON(VIRTIO_PCI_COMMON_STATUS !=
180 offsetof(struct virtio_pci_common_cfg, device_status));
181 BUILD_BUG_ON(VIRTIO_PCI_COMMON_CFGGENERATION !=
182 offsetof(struct virtio_pci_common_cfg, config_generation));
183 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SELECT !=
184 offsetof(struct virtio_pci_common_cfg, queue_select));
185 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SIZE !=
186 offsetof(struct virtio_pci_common_cfg, queue_size));
187 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_MSIX !=
188 offsetof(struct virtio_pci_common_cfg, queue_msix_vector));
189 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_ENABLE !=
190 offsetof(struct virtio_pci_common_cfg, queue_enable));
191 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NOFF !=
192 offsetof(struct virtio_pci_common_cfg, queue_notify_off));
193 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCLO !=
194 offsetof(struct virtio_pci_common_cfg, queue_desc_lo));
195 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCHI !=
196 offsetof(struct virtio_pci_common_cfg, queue_desc_hi));
197 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILLO !=
198 offsetof(struct virtio_pci_common_cfg, queue_avail_lo));
199 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILHI !=
200 offsetof(struct virtio_pci_common_cfg, queue_avail_hi));
201 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDLO !=
202 offsetof(struct virtio_pci_common_cfg, queue_used_lo));
203 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDHI !=
204 offsetof(struct virtio_pci_common_cfg, queue_used_hi));
205 }
206
207 /*
208 * vp_modern_probe: probe the modern virtio pci device, note that the
209 * caller is required to enable PCI device before calling this function.
210 * @mdev: the modern virtio-pci device
211 *
212 * Return 0 on succeed otherwise fail
213 */
vp_modern_probe(struct virtio_pci_modern_device * mdev)214 int vp_modern_probe(struct virtio_pci_modern_device *mdev)
215 {
216 struct pci_dev *pci_dev = mdev->pci_dev;
217 int err, common, isr, notify, device;
218 u32 notify_length;
219 u32 notify_offset;
220
221 check_offsets();
222
223 /* We only own devices >= 0x1000 and <= 0x107f: leave the rest. */
224 if (pci_dev->device < 0x1000 || pci_dev->device > 0x107f)
225 return -ENODEV;
226
227 if (pci_dev->device < 0x1040) {
228 /* Transitional devices: use the PCI subsystem device id as
229 * virtio device id, same as legacy driver always did.
230 */
231 mdev->id.device = pci_dev->subsystem_device;
232 } else {
233 /* Modern devices: simply use PCI device id, but start from 0x1040. */
234 mdev->id.device = pci_dev->device - 0x1040;
235 }
236 mdev->id.vendor = pci_dev->subsystem_vendor;
237
238 /* check for a common config: if not, use legacy mode (bar 0). */
239 common = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG,
240 IORESOURCE_IO | IORESOURCE_MEM,
241 &mdev->modern_bars);
242 if (!common) {
243 dev_info(&pci_dev->dev,
244 "virtio_pci: leaving for legacy driver\n");
245 return -ENODEV;
246 }
247
248 /* If common is there, these should be too... */
249 isr = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_ISR_CFG,
250 IORESOURCE_IO | IORESOURCE_MEM,
251 &mdev->modern_bars);
252 notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG,
253 IORESOURCE_IO | IORESOURCE_MEM,
254 &mdev->modern_bars);
255 if (!isr || !notify) {
256 dev_err(&pci_dev->dev,
257 "virtio_pci: missing capabilities %i/%i/%i\n",
258 common, isr, notify);
259 return -EINVAL;
260 }
261
262 err = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(64));
263 if (err)
264 err = dma_set_mask_and_coherent(&pci_dev->dev,
265 DMA_BIT_MASK(32));
266 if (err)
267 dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n");
268
269 /* Device capability is only mandatory for devices that have
270 * device-specific configuration.
271 */
272 device = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG,
273 IORESOURCE_IO | IORESOURCE_MEM,
274 &mdev->modern_bars);
275
276 err = pci_request_selected_regions(pci_dev, mdev->modern_bars,
277 "virtio-pci-modern");
278 if (err)
279 return err;
280
281 err = -EINVAL;
282 mdev->common = vp_modern_map_capability(mdev, common,
283 sizeof(struct virtio_pci_common_cfg), 4,
284 0, sizeof(struct virtio_pci_common_cfg),
285 NULL, NULL);
286 if (!mdev->common)
287 goto err_map_common;
288 mdev->isr = vp_modern_map_capability(mdev, isr, sizeof(u8), 1,
289 0, 1,
290 NULL, NULL);
291 if (!mdev->isr)
292 goto err_map_isr;
293
294 /* Read notify_off_multiplier from config space. */
295 pci_read_config_dword(pci_dev,
296 notify + offsetof(struct virtio_pci_notify_cap,
297 notify_off_multiplier),
298 &mdev->notify_offset_multiplier);
299 /* Read notify length and offset from config space. */
300 pci_read_config_dword(pci_dev,
301 notify + offsetof(struct virtio_pci_notify_cap,
302 cap.length),
303 ¬ify_length);
304
305 pci_read_config_dword(pci_dev,
306 notify + offsetof(struct virtio_pci_notify_cap,
307 cap.offset),
308 ¬ify_offset);
309
310 /* We don't know how many VQs we'll map, ahead of the time.
311 * If notify length is small, map it all now.
312 * Otherwise, map each VQ individually later.
313 */
314 if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) {
315 mdev->notify_base = vp_modern_map_capability(mdev, notify,
316 2, 2,
317 0, notify_length,
318 &mdev->notify_len,
319 &mdev->notify_pa);
320 if (!mdev->notify_base)
321 goto err_map_notify;
322 } else {
323 mdev->notify_map_cap = notify;
324 }
325
326 /* Again, we don't know how much we should map, but PAGE_SIZE
327 * is more than enough for all existing devices.
328 */
329 if (device) {
330 mdev->device = vp_modern_map_capability(mdev, device, 0, 4,
331 0, PAGE_SIZE,
332 &mdev->device_len,
333 NULL);
334 if (!mdev->device)
335 goto err_map_device;
336 }
337
338 return 0;
339
340 err_map_device:
341 if (mdev->notify_base)
342 pci_iounmap(pci_dev, mdev->notify_base);
343 err_map_notify:
344 pci_iounmap(pci_dev, mdev->isr);
345 err_map_isr:
346 pci_iounmap(pci_dev, mdev->common);
347 err_map_common:
348 pci_release_selected_regions(pci_dev, mdev->modern_bars);
349 return err;
350 }
351 EXPORT_SYMBOL_GPL(vp_modern_probe);
352
353 /*
354 * vp_modern_remove: remove and cleanup the modern virtio pci device
355 * @mdev: the modern virtio-pci device
356 */
vp_modern_remove(struct virtio_pci_modern_device * mdev)357 void vp_modern_remove(struct virtio_pci_modern_device *mdev)
358 {
359 struct pci_dev *pci_dev = mdev->pci_dev;
360
361 if (mdev->device)
362 pci_iounmap(pci_dev, mdev->device);
363 if (mdev->notify_base)
364 pci_iounmap(pci_dev, mdev->notify_base);
365 pci_iounmap(pci_dev, mdev->isr);
366 pci_iounmap(pci_dev, mdev->common);
367 pci_release_selected_regions(pci_dev, mdev->modern_bars);
368 }
369 EXPORT_SYMBOL_GPL(vp_modern_remove);
370
371 /*
372 * vp_modern_get_features - get features from device
373 * @mdev: the modern virtio-pci device
374 *
375 * Returns the features read from the device
376 */
vp_modern_get_features(struct virtio_pci_modern_device * mdev)377 u64 vp_modern_get_features(struct virtio_pci_modern_device *mdev)
378 {
379 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
380
381 u64 features;
382
383 vp_iowrite32(0, &cfg->device_feature_select);
384 features = vp_ioread32(&cfg->device_feature);
385 vp_iowrite32(1, &cfg->device_feature_select);
386 features |= ((u64)vp_ioread32(&cfg->device_feature) << 32);
387
388 return features;
389 }
390 EXPORT_SYMBOL_GPL(vp_modern_get_features);
391
392 /*
393 * vp_modern_get_driver_features - get driver features from device
394 * @mdev: the modern virtio-pci device
395 *
396 * Returns the driver features read from the device
397 */
vp_modern_get_driver_features(struct virtio_pci_modern_device * mdev)398 u64 vp_modern_get_driver_features(struct virtio_pci_modern_device *mdev)
399 {
400 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
401
402 u64 features;
403
404 vp_iowrite32(0, &cfg->guest_feature_select);
405 features = vp_ioread32(&cfg->guest_feature);
406 vp_iowrite32(1, &cfg->guest_feature_select);
407 features |= ((u64)vp_ioread32(&cfg->guest_feature) << 32);
408
409 return features;
410 }
411 EXPORT_SYMBOL_GPL(vp_modern_get_driver_features);
412
413 /*
414 * vp_modern_set_features - set features to device
415 * @mdev: the modern virtio-pci device
416 * @features: the features set to device
417 */
vp_modern_set_features(struct virtio_pci_modern_device * mdev,u64 features)418 void vp_modern_set_features(struct virtio_pci_modern_device *mdev,
419 u64 features)
420 {
421 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
422
423 vp_iowrite32(0, &cfg->guest_feature_select);
424 vp_iowrite32((u32)features, &cfg->guest_feature);
425 vp_iowrite32(1, &cfg->guest_feature_select);
426 vp_iowrite32(features >> 32, &cfg->guest_feature);
427 }
428 EXPORT_SYMBOL_GPL(vp_modern_set_features);
429
430 /*
431 * vp_modern_generation - get the device genreation
432 * @mdev: the modern virtio-pci device
433 *
434 * Returns the genreation read from device
435 */
vp_modern_generation(struct virtio_pci_modern_device * mdev)436 u32 vp_modern_generation(struct virtio_pci_modern_device *mdev)
437 {
438 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
439
440 return vp_ioread8(&cfg->config_generation);
441 }
442 EXPORT_SYMBOL_GPL(vp_modern_generation);
443
444 /*
445 * vp_modern_get_status - get the device status
446 * @mdev: the modern virtio-pci device
447 *
448 * Returns the status read from device
449 */
vp_modern_get_status(struct virtio_pci_modern_device * mdev)450 u8 vp_modern_get_status(struct virtio_pci_modern_device *mdev)
451 {
452 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
453
454 return vp_ioread8(&cfg->device_status);
455 }
456 EXPORT_SYMBOL_GPL(vp_modern_get_status);
457
458 /*
459 * vp_modern_set_status - set status to device
460 * @mdev: the modern virtio-pci device
461 * @status: the status set to device
462 */
vp_modern_set_status(struct virtio_pci_modern_device * mdev,u8 status)463 void vp_modern_set_status(struct virtio_pci_modern_device *mdev,
464 u8 status)
465 {
466 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
467
468 /*
469 * Per memory-barriers.txt, wmb() is not needed to guarantee
470 * that the cache coherent memory writes have completed
471 * before writing to the MMIO region.
472 */
473 vp_iowrite8(status, &cfg->device_status);
474 }
475 EXPORT_SYMBOL_GPL(vp_modern_set_status);
476
477 /*
478 * vp_modern_queue_vector - set the MSIX vector for a specific virtqueue
479 * @mdev: the modern virtio-pci device
480 * @index: queue index
481 * @vector: the config vector
482 *
483 * Returns the config vector read from the device
484 */
vp_modern_queue_vector(struct virtio_pci_modern_device * mdev,u16 index,u16 vector)485 u16 vp_modern_queue_vector(struct virtio_pci_modern_device *mdev,
486 u16 index, u16 vector)
487 {
488 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
489
490 vp_iowrite16(index, &cfg->queue_select);
491 vp_iowrite16(vector, &cfg->queue_msix_vector);
492 /* Flush the write out to device */
493 return vp_ioread16(&cfg->queue_msix_vector);
494 }
495 EXPORT_SYMBOL_GPL(vp_modern_queue_vector);
496
497 /*
498 * vp_modern_config_vector - set the vector for config interrupt
499 * @mdev: the modern virtio-pci device
500 * @vector: the config vector
501 *
502 * Returns the config vector read from the device
503 */
vp_modern_config_vector(struct virtio_pci_modern_device * mdev,u16 vector)504 u16 vp_modern_config_vector(struct virtio_pci_modern_device *mdev,
505 u16 vector)
506 {
507 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
508
509 /* Setup the vector used for configuration events */
510 vp_iowrite16(vector, &cfg->msix_config);
511 /* Verify we had enough resources to assign the vector */
512 /* Will also flush the write out to device */
513 return vp_ioread16(&cfg->msix_config);
514 }
515 EXPORT_SYMBOL_GPL(vp_modern_config_vector);
516
517 /*
518 * vp_modern_queue_address - set the virtqueue address
519 * @mdev: the modern virtio-pci device
520 * @index: the queue index
521 * @desc_addr: address of the descriptor area
522 * @driver_addr: address of the driver area
523 * @device_addr: address of the device area
524 */
vp_modern_queue_address(struct virtio_pci_modern_device * mdev,u16 index,u64 desc_addr,u64 driver_addr,u64 device_addr)525 void vp_modern_queue_address(struct virtio_pci_modern_device *mdev,
526 u16 index, u64 desc_addr, u64 driver_addr,
527 u64 device_addr)
528 {
529 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
530
531 vp_iowrite16(index, &cfg->queue_select);
532
533 vp_iowrite64_twopart(desc_addr, &cfg->queue_desc_lo,
534 &cfg->queue_desc_hi);
535 vp_iowrite64_twopart(driver_addr, &cfg->queue_avail_lo,
536 &cfg->queue_avail_hi);
537 vp_iowrite64_twopart(device_addr, &cfg->queue_used_lo,
538 &cfg->queue_used_hi);
539 }
540 EXPORT_SYMBOL_GPL(vp_modern_queue_address);
541
542 /*
543 * vp_modern_set_queue_enable - enable a virtqueue
544 * @mdev: the modern virtio-pci device
545 * @index: the queue index
546 * @enable: whether the virtqueue is enable or not
547 */
vp_modern_set_queue_enable(struct virtio_pci_modern_device * mdev,u16 index,bool enable)548 void vp_modern_set_queue_enable(struct virtio_pci_modern_device *mdev,
549 u16 index, bool enable)
550 {
551 vp_iowrite16(index, &mdev->common->queue_select);
552 vp_iowrite16(enable, &mdev->common->queue_enable);
553 }
554 EXPORT_SYMBOL_GPL(vp_modern_set_queue_enable);
555
556 /*
557 * vp_modern_get_queue_enable - enable a virtqueue
558 * @mdev: the modern virtio-pci device
559 * @index: the queue index
560 *
561 * Returns whether a virtqueue is enabled or not
562 */
vp_modern_get_queue_enable(struct virtio_pci_modern_device * mdev,u16 index)563 bool vp_modern_get_queue_enable(struct virtio_pci_modern_device *mdev,
564 u16 index)
565 {
566 vp_iowrite16(index, &mdev->common->queue_select);
567
568 return vp_ioread16(&mdev->common->queue_enable);
569 }
570 EXPORT_SYMBOL_GPL(vp_modern_get_queue_enable);
571
572 /*
573 * vp_modern_set_queue_size - set size for a virtqueue
574 * @mdev: the modern virtio-pci device
575 * @index: the queue index
576 * @size: the size of the virtqueue
577 */
vp_modern_set_queue_size(struct virtio_pci_modern_device * mdev,u16 index,u16 size)578 void vp_modern_set_queue_size(struct virtio_pci_modern_device *mdev,
579 u16 index, u16 size)
580 {
581 vp_iowrite16(index, &mdev->common->queue_select);
582 vp_iowrite16(size, &mdev->common->queue_size);
583
584 }
585 EXPORT_SYMBOL_GPL(vp_modern_set_queue_size);
586
587 /*
588 * vp_modern_get_queue_size - get size for a virtqueue
589 * @mdev: the modern virtio-pci device
590 * @index: the queue index
591 *
592 * Returns the size of the virtqueue
593 */
vp_modern_get_queue_size(struct virtio_pci_modern_device * mdev,u16 index)594 u16 vp_modern_get_queue_size(struct virtio_pci_modern_device *mdev,
595 u16 index)
596 {
597 vp_iowrite16(index, &mdev->common->queue_select);
598
599 return vp_ioread16(&mdev->common->queue_size);
600
601 }
602 EXPORT_SYMBOL_GPL(vp_modern_get_queue_size);
603
604 /*
605 * vp_modern_get_num_queues - get the number of virtqueues
606 * @mdev: the modern virtio-pci device
607 *
608 * Returns the number of virtqueues
609 */
vp_modern_get_num_queues(struct virtio_pci_modern_device * mdev)610 u16 vp_modern_get_num_queues(struct virtio_pci_modern_device *mdev)
611 {
612 return vp_ioread16(&mdev->common->num_queues);
613 }
614 EXPORT_SYMBOL_GPL(vp_modern_get_num_queues);
615
616 /*
617 * vp_modern_get_queue_notify_off - get notification offset for a virtqueue
618 * @mdev: the modern virtio-pci device
619 * @index: the queue index
620 *
621 * Returns the notification offset for a virtqueue
622 */
vp_modern_get_queue_notify_off(struct virtio_pci_modern_device * mdev,u16 index)623 static u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev,
624 u16 index)
625 {
626 vp_iowrite16(index, &mdev->common->queue_select);
627
628 return vp_ioread16(&mdev->common->queue_notify_off);
629 }
630
631 /*
632 * vp_modern_map_vq_notify - map notification area for a
633 * specific virtqueue
634 * @mdev: the modern virtio-pci device
635 * @index: the queue index
636 * @pa: the pointer to the physical address of the nofity area
637 *
638 * Returns the address of the notification area
639 */
vp_modern_map_vq_notify(struct virtio_pci_modern_device * mdev,u16 index,resource_size_t * pa)640 void __iomem *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,
641 u16 index, resource_size_t *pa)
642 {
643 u16 off = vp_modern_get_queue_notify_off(mdev, index);
644
645 if (mdev->notify_base) {
646 /* offset should not wrap */
647 if ((u64)off * mdev->notify_offset_multiplier + 2
648 > mdev->notify_len) {
649 dev_warn(&mdev->pci_dev->dev,
650 "bad notification offset %u (x %u) "
651 "for queue %u > %zd",
652 off, mdev->notify_offset_multiplier,
653 index, mdev->notify_len);
654 return NULL;
655 }
656 if (pa)
657 *pa = mdev->notify_pa +
658 off * mdev->notify_offset_multiplier;
659 return mdev->notify_base + off * mdev->notify_offset_multiplier;
660 } else {
661 return vp_modern_map_capability(mdev,
662 mdev->notify_map_cap, 2, 2,
663 off * mdev->notify_offset_multiplier, 2,
664 NULL, pa);
665 }
666 }
667 EXPORT_SYMBOL_GPL(vp_modern_map_vq_notify);
668
669 MODULE_VERSION("0.1");
670 MODULE_DESCRIPTION("Modern Virtio PCI Device");
671 MODULE_AUTHOR("Jason Wang <jasowang@redhat.com>");
672 MODULE_LICENSE("GPL");
673