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#include <linux/delay.h>
7
8/*
9 * vp_modern_map_capability - map a part of virtio pci capability
10 * @mdev: the modern virtio-pci device
11 * @off: offset of the capability
12 * @minlen: minimal length of the capability
13 * @align: align requirement
14 * @start: start from the capability
15 * @size: map size
16 * @len: the length that is actually mapped
17 * @pa: physical address of the capability
18 *
19 * Returns the io address of for the part of the capability
20 */
21static void __iomem *
22vp_modern_map_capability(struct virtio_pci_modern_device *mdev, int off,
23 size_t minlen, u32 align, u32 start, u32 size,
24 size_t *len, resource_size_t *pa)
25{
26 struct pci_dev *dev = mdev->pci_dev;
27 u8 bar;
28 u32 offset, length;
29 void __iomem *p;
30
31 pci_read_config_byte(dev, where: off + offsetof(struct virtio_pci_cap,
32 bar),
33 val: &bar);
34 pci_read_config_dword(dev, where: off + offsetof(struct virtio_pci_cap, offset),
35 val: &offset);
36 pci_read_config_dword(dev, where: off + offsetof(struct virtio_pci_cap, length),
37 val: &length);
38
39 /* Check if the BAR may have changed since we requested the region. */
40 if (bar >= PCI_STD_NUM_BARS || !(mdev->modern_bars & (1 << bar))) {
41 dev_err(&dev->dev,
42 "virtio_pci: bar unexpectedly changed to %u\n", bar);
43 return NULL;
44 }
45
46 if (length <= start) {
47 dev_err(&dev->dev,
48 "virtio_pci: bad capability len %u (>%u expected)\n",
49 length, start);
50 return NULL;
51 }
52
53 if (length - start < minlen) {
54 dev_err(&dev->dev,
55 "virtio_pci: bad capability len %u (>=%zu expected)\n",
56 length, minlen);
57 return NULL;
58 }
59
60 length -= start;
61
62 if (start + offset < offset) {
63 dev_err(&dev->dev,
64 "virtio_pci: map wrap-around %u+%u\n",
65 start, offset);
66 return NULL;
67 }
68
69 offset += start;
70
71 if (offset & (align - 1)) {
72 dev_err(&dev->dev,
73 "virtio_pci: offset %u not aligned to %u\n",
74 offset, align);
75 return NULL;
76 }
77
78 if (length > size)
79 length = size;
80
81 if (len)
82 *len = length;
83
84 if (minlen + offset < minlen ||
85 minlen + offset > pci_resource_len(dev, bar)) {
86 dev_err(&dev->dev,
87 "virtio_pci: map virtio %zu@%u "
88 "out of range on bar %i length %lu\n",
89 minlen, offset,
90 bar, (unsigned long)pci_resource_len(dev, bar));
91 return NULL;
92 }
93
94 p = pci_iomap_range(dev, bar, offset, maxlen: length);
95 if (!p)
96 dev_err(&dev->dev,
97 "virtio_pci: unable to map virtio %u@%u on bar %i\n",
98 length, offset, bar);
99 else if (pa)
100 *pa = pci_resource_start(dev, bar) + offset;
101
102 return p;
103}
104
105/**
106 * virtio_pci_find_capability - walk capabilities to find device info.
107 * @dev: the pci device
108 * @cfg_type: the VIRTIO_PCI_CAP_* value we seek
109 * @ioresource_types: IORESOURCE_MEM and/or IORESOURCE_IO.
110 * @bars: the bitmask of BARs
111 *
112 * Returns offset of the capability, or 0.
113 */
114static inline int virtio_pci_find_capability(struct pci_dev *dev, u8 cfg_type,
115 u32 ioresource_types, int *bars)
116{
117 int pos;
118
119 for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR);
120 pos > 0;
121 pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) {
122 u8 type, bar;
123 pci_read_config_byte(dev, where: pos + offsetof(struct virtio_pci_cap,
124 cfg_type),
125 val: &type);
126 pci_read_config_byte(dev, where: pos + offsetof(struct virtio_pci_cap,
127 bar),
128 val: &bar);
129
130 /* Ignore structures with reserved BAR values */
131 if (bar >= PCI_STD_NUM_BARS)
132 continue;
133
134 if (type == cfg_type) {
135 if (pci_resource_len(dev, bar) &&
136 pci_resource_flags(dev, bar) & ioresource_types) {
137 *bars |= (1 << bar);
138 return pos;
139 }
140 }
141 }
142 return 0;
143}
144
145/* This is part of the ABI. Don't screw with it. */
146static inline void check_offsets(void)
147{
148 /* Note: disk space was harmed in compilation of this function. */
149 BUILD_BUG_ON(VIRTIO_PCI_CAP_VNDR !=
150 offsetof(struct virtio_pci_cap, cap_vndr));
151 BUILD_BUG_ON(VIRTIO_PCI_CAP_NEXT !=
152 offsetof(struct virtio_pci_cap, cap_next));
153 BUILD_BUG_ON(VIRTIO_PCI_CAP_LEN !=
154 offsetof(struct virtio_pci_cap, cap_len));
155 BUILD_BUG_ON(VIRTIO_PCI_CAP_CFG_TYPE !=
156 offsetof(struct virtio_pci_cap, cfg_type));
157 BUILD_BUG_ON(VIRTIO_PCI_CAP_BAR !=
158 offsetof(struct virtio_pci_cap, bar));
159 BUILD_BUG_ON(VIRTIO_PCI_CAP_OFFSET !=
160 offsetof(struct virtio_pci_cap, offset));
161 BUILD_BUG_ON(VIRTIO_PCI_CAP_LENGTH !=
162 offsetof(struct virtio_pci_cap, length));
163 BUILD_BUG_ON(VIRTIO_PCI_NOTIFY_CAP_MULT !=
164 offsetof(struct virtio_pci_notify_cap,
165 notify_off_multiplier));
166 BUILD_BUG_ON(VIRTIO_PCI_COMMON_DFSELECT !=
167 offsetof(struct virtio_pci_common_cfg,
168 device_feature_select));
169 BUILD_BUG_ON(VIRTIO_PCI_COMMON_DF !=
170 offsetof(struct virtio_pci_common_cfg, device_feature));
171 BUILD_BUG_ON(VIRTIO_PCI_COMMON_GFSELECT !=
172 offsetof(struct virtio_pci_common_cfg,
173 guest_feature_select));
174 BUILD_BUG_ON(VIRTIO_PCI_COMMON_GF !=
175 offsetof(struct virtio_pci_common_cfg, guest_feature));
176 BUILD_BUG_ON(VIRTIO_PCI_COMMON_MSIX !=
177 offsetof(struct virtio_pci_common_cfg, msix_config));
178 BUILD_BUG_ON(VIRTIO_PCI_COMMON_NUMQ !=
179 offsetof(struct virtio_pci_common_cfg, num_queues));
180 BUILD_BUG_ON(VIRTIO_PCI_COMMON_STATUS !=
181 offsetof(struct virtio_pci_common_cfg, device_status));
182 BUILD_BUG_ON(VIRTIO_PCI_COMMON_CFGGENERATION !=
183 offsetof(struct virtio_pci_common_cfg, config_generation));
184 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SELECT !=
185 offsetof(struct virtio_pci_common_cfg, queue_select));
186 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SIZE !=
187 offsetof(struct virtio_pci_common_cfg, queue_size));
188 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_MSIX !=
189 offsetof(struct virtio_pci_common_cfg, queue_msix_vector));
190 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_ENABLE !=
191 offsetof(struct virtio_pci_common_cfg, queue_enable));
192 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NOFF !=
193 offsetof(struct virtio_pci_common_cfg, queue_notify_off));
194 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCLO !=
195 offsetof(struct virtio_pci_common_cfg, queue_desc_lo));
196 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCHI !=
197 offsetof(struct virtio_pci_common_cfg, queue_desc_hi));
198 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILLO !=
199 offsetof(struct virtio_pci_common_cfg, queue_avail_lo));
200 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILHI !=
201 offsetof(struct virtio_pci_common_cfg, queue_avail_hi));
202 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDLO !=
203 offsetof(struct virtio_pci_common_cfg, queue_used_lo));
204 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDHI !=
205 offsetof(struct virtio_pci_common_cfg, queue_used_hi));
206 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NDATA !=
207 offsetof(struct virtio_pci_modern_common_cfg, queue_notify_data));
208 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_RESET !=
209 offsetof(struct virtio_pci_modern_common_cfg, queue_reset));
210 BUILD_BUG_ON(VIRTIO_PCI_COMMON_ADM_Q_IDX !=
211 offsetof(struct virtio_pci_modern_common_cfg, admin_queue_index));
212 BUILD_BUG_ON(VIRTIO_PCI_COMMON_ADM_Q_NUM !=
213 offsetof(struct virtio_pci_modern_common_cfg, admin_queue_num));
214}
215
216/*
217 * vp_modern_probe: probe the modern virtio pci device, note that the
218 * caller is required to enable PCI device before calling this function.
219 * @mdev: the modern virtio-pci device
220 *
221 * Return 0 on succeed otherwise fail
222 */
223int vp_modern_probe(struct virtio_pci_modern_device *mdev)
224{
225 struct pci_dev *pci_dev = mdev->pci_dev;
226 int err, common, isr, notify, device;
227 u32 notify_length;
228 u32 notify_offset;
229 int devid;
230
231 check_offsets();
232
233 if (mdev->device_id_check) {
234 devid = mdev->device_id_check(pci_dev);
235 if (devid < 0)
236 return devid;
237 mdev->id.device = devid;
238 } else {
239 /* We only own devices >= 0x1000 and <= 0x107f: leave the rest. */
240 if (pci_dev->device < 0x1000 || pci_dev->device > 0x107f)
241 return -ENODEV;
242
243 if (pci_dev->device < 0x1040) {
244 /* Transitional devices: use the PCI subsystem device id as
245 * virtio device id, same as legacy driver always did.
246 */
247 mdev->id.device = pci_dev->subsystem_device;
248 } else {
249 /* Modern devices: simply use PCI device id, but start from 0x1040. */
250 mdev->id.device = pci_dev->device - 0x1040;
251 }
252 }
253 mdev->id.vendor = pci_dev->subsystem_vendor;
254
255 /* check for a common config: if not, use legacy mode (bar 0). */
256 common = virtio_pci_find_capability(dev: pci_dev, VIRTIO_PCI_CAP_COMMON_CFG,
257 IORESOURCE_IO | IORESOURCE_MEM,
258 bars: &mdev->modern_bars);
259 if (!common) {
260 dev_info(&pci_dev->dev,
261 "virtio_pci: leaving for legacy driver\n");
262 return -ENODEV;
263 }
264
265 /* If common is there, these should be too... */
266 isr = virtio_pci_find_capability(dev: pci_dev, VIRTIO_PCI_CAP_ISR_CFG,
267 IORESOURCE_IO | IORESOURCE_MEM,
268 bars: &mdev->modern_bars);
269 notify = virtio_pci_find_capability(dev: pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG,
270 IORESOURCE_IO | IORESOURCE_MEM,
271 bars: &mdev->modern_bars);
272 if (!isr || !notify) {
273 dev_err(&pci_dev->dev,
274 "virtio_pci: missing capabilities %i/%i/%i\n",
275 common, isr, notify);
276 return -EINVAL;
277 }
278
279 err = dma_set_mask_and_coherent(dev: &pci_dev->dev,
280 mask: mdev->dma_mask ? : DMA_BIT_MASK(64));
281 if (err)
282 err = dma_set_mask_and_coherent(dev: &pci_dev->dev,
283 DMA_BIT_MASK(32));
284 if (err)
285 dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n");
286
287 /* Device capability is only mandatory for devices that have
288 * device-specific configuration.
289 */
290 device = virtio_pci_find_capability(dev: pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG,
291 IORESOURCE_IO | IORESOURCE_MEM,
292 bars: &mdev->modern_bars);
293
294 err = pci_request_selected_regions(pci_dev, mdev->modern_bars,
295 "virtio-pci-modern");
296 if (err)
297 return err;
298
299 err = -EINVAL;
300 mdev->common = vp_modern_map_capability(mdev, off: common,
301 minlen: sizeof(struct virtio_pci_common_cfg), align: 4, start: 0,
302 offsetofend(struct virtio_pci_modern_common_cfg,
303 admin_queue_num),
304 len: &mdev->common_len, NULL);
305 if (!mdev->common)
306 goto err_map_common;
307 mdev->isr = vp_modern_map_capability(mdev, off: isr, minlen: sizeof(u8), align: 1,
308 start: 0, size: 1,
309 NULL, NULL);
310 if (!mdev->isr)
311 goto err_map_isr;
312
313 /* Read notify_off_multiplier from config space. */
314 pci_read_config_dword(dev: pci_dev,
315 where: notify + offsetof(struct virtio_pci_notify_cap,
316 notify_off_multiplier),
317 val: &mdev->notify_offset_multiplier);
318 /* Read notify length and offset from config space. */
319 pci_read_config_dword(dev: pci_dev,
320 where: notify + offsetof(struct virtio_pci_notify_cap,
321 cap.length),
322 val: &notify_length);
323
324 pci_read_config_dword(dev: pci_dev,
325 where: notify + offsetof(struct virtio_pci_notify_cap,
326 cap.offset),
327 val: &notify_offset);
328
329 /* We don't know how many VQs we'll map, ahead of the time.
330 * If notify length is small, map it all now.
331 * Otherwise, map each VQ individually later.
332 */
333 if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) {
334 mdev->notify_base = vp_modern_map_capability(mdev, off: notify,
335 minlen: 2, align: 2,
336 start: 0, size: notify_length,
337 len: &mdev->notify_len,
338 pa: &mdev->notify_pa);
339 if (!mdev->notify_base)
340 goto err_map_notify;
341 } else {
342 mdev->notify_map_cap = notify;
343 }
344
345 /* Again, we don't know how much we should map, but PAGE_SIZE
346 * is more than enough for all existing devices.
347 */
348 if (device) {
349 mdev->device = vp_modern_map_capability(mdev, off: device, minlen: 0, align: 4,
350 start: 0, PAGE_SIZE,
351 len: &mdev->device_len,
352 NULL);
353 if (!mdev->device)
354 goto err_map_device;
355 }
356
357 return 0;
358
359err_map_device:
360 if (mdev->notify_base)
361 pci_iounmap(dev: pci_dev, mdev->notify_base);
362err_map_notify:
363 pci_iounmap(dev: pci_dev, mdev->isr);
364err_map_isr:
365 pci_iounmap(dev: pci_dev, mdev->common);
366err_map_common:
367 pci_release_selected_regions(pci_dev, mdev->modern_bars);
368 return err;
369}
370EXPORT_SYMBOL_GPL(vp_modern_probe);
371
372/*
373 * vp_modern_remove: remove and cleanup the modern virtio pci device
374 * @mdev: the modern virtio-pci device
375 */
376void vp_modern_remove(struct virtio_pci_modern_device *mdev)
377{
378 struct pci_dev *pci_dev = mdev->pci_dev;
379
380 if (mdev->device)
381 pci_iounmap(dev: pci_dev, mdev->device);
382 if (mdev->notify_base)
383 pci_iounmap(dev: pci_dev, mdev->notify_base);
384 pci_iounmap(dev: pci_dev, mdev->isr);
385 pci_iounmap(dev: pci_dev, mdev->common);
386 pci_release_selected_regions(pci_dev, mdev->modern_bars);
387}
388EXPORT_SYMBOL_GPL(vp_modern_remove);
389
390/*
391 * vp_modern_get_features - get features from device
392 * @mdev: the modern virtio-pci device
393 *
394 * Returns the features read from the device
395 */
396u64 vp_modern_get_features(struct virtio_pci_modern_device *mdev)
397{
398 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
399
400 u64 features;
401
402 vp_iowrite32(value: 0, addr: &cfg->device_feature_select);
403 features = vp_ioread32(addr: &cfg->device_feature);
404 vp_iowrite32(value: 1, addr: &cfg->device_feature_select);
405 features |= ((u64)vp_ioread32(addr: &cfg->device_feature) << 32);
406
407 return features;
408}
409EXPORT_SYMBOL_GPL(vp_modern_get_features);
410
411/*
412 * vp_modern_get_driver_features - get driver features from device
413 * @mdev: the modern virtio-pci device
414 *
415 * Returns the driver features read from the device
416 */
417u64 vp_modern_get_driver_features(struct virtio_pci_modern_device *mdev)
418{
419 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
420
421 u64 features;
422
423 vp_iowrite32(value: 0, addr: &cfg->guest_feature_select);
424 features = vp_ioread32(addr: &cfg->guest_feature);
425 vp_iowrite32(value: 1, addr: &cfg->guest_feature_select);
426 features |= ((u64)vp_ioread32(addr: &cfg->guest_feature) << 32);
427
428 return features;
429}
430EXPORT_SYMBOL_GPL(vp_modern_get_driver_features);
431
432/*
433 * vp_modern_set_features - set features to device
434 * @mdev: the modern virtio-pci device
435 * @features: the features set to device
436 */
437void vp_modern_set_features(struct virtio_pci_modern_device *mdev,
438 u64 features)
439{
440 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
441
442 vp_iowrite32(value: 0, addr: &cfg->guest_feature_select);
443 vp_iowrite32(value: (u32)features, addr: &cfg->guest_feature);
444 vp_iowrite32(value: 1, addr: &cfg->guest_feature_select);
445 vp_iowrite32(value: features >> 32, addr: &cfg->guest_feature);
446}
447EXPORT_SYMBOL_GPL(vp_modern_set_features);
448
449/*
450 * vp_modern_generation - get the device genreation
451 * @mdev: the modern virtio-pci device
452 *
453 * Returns the genreation read from device
454 */
455u32 vp_modern_generation(struct virtio_pci_modern_device *mdev)
456{
457 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
458
459 return vp_ioread8(addr: &cfg->config_generation);
460}
461EXPORT_SYMBOL_GPL(vp_modern_generation);
462
463/*
464 * vp_modern_get_status - get the device status
465 * @mdev: the modern virtio-pci device
466 *
467 * Returns the status read from device
468 */
469u8 vp_modern_get_status(struct virtio_pci_modern_device *mdev)
470{
471 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
472
473 return vp_ioread8(addr: &cfg->device_status);
474}
475EXPORT_SYMBOL_GPL(vp_modern_get_status);
476
477/*
478 * vp_modern_set_status - set status to device
479 * @mdev: the modern virtio-pci device
480 * @status: the status set to device
481 */
482void vp_modern_set_status(struct virtio_pci_modern_device *mdev,
483 u8 status)
484{
485 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
486
487 /*
488 * Per memory-barriers.txt, wmb() is not needed to guarantee
489 * that the cache coherent memory writes have completed
490 * before writing to the MMIO region.
491 */
492 vp_iowrite8(value: status, addr: &cfg->device_status);
493}
494EXPORT_SYMBOL_GPL(vp_modern_set_status);
495
496/*
497 * vp_modern_get_queue_reset - get the queue reset status
498 * @mdev: the modern virtio-pci device
499 * @index: queue index
500 */
501int vp_modern_get_queue_reset(struct virtio_pci_modern_device *mdev, u16 index)
502{
503 struct virtio_pci_modern_common_cfg __iomem *cfg;
504
505 cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common;
506
507 vp_iowrite16(value: index, addr: &cfg->cfg.queue_select);
508 return vp_ioread16(addr: &cfg->queue_reset);
509}
510EXPORT_SYMBOL_GPL(vp_modern_get_queue_reset);
511
512/*
513 * vp_modern_set_queue_reset - reset the queue
514 * @mdev: the modern virtio-pci device
515 * @index: queue index
516 */
517void vp_modern_set_queue_reset(struct virtio_pci_modern_device *mdev, u16 index)
518{
519 struct virtio_pci_modern_common_cfg __iomem *cfg;
520
521 cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common;
522
523 vp_iowrite16(value: index, addr: &cfg->cfg.queue_select);
524 vp_iowrite16(value: 1, addr: &cfg->queue_reset);
525
526 while (vp_ioread16(addr: &cfg->queue_reset))
527 msleep(msecs: 1);
528
529 while (vp_ioread16(addr: &cfg->cfg.queue_enable))
530 msleep(msecs: 1);
531}
532EXPORT_SYMBOL_GPL(vp_modern_set_queue_reset);
533
534/*
535 * vp_modern_queue_vector - set the MSIX vector for a specific virtqueue
536 * @mdev: the modern virtio-pci device
537 * @index: queue index
538 * @vector: the config vector
539 *
540 * Returns the config vector read from the device
541 */
542u16 vp_modern_queue_vector(struct virtio_pci_modern_device *mdev,
543 u16 index, u16 vector)
544{
545 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
546
547 vp_iowrite16(value: index, addr: &cfg->queue_select);
548 vp_iowrite16(value: vector, addr: &cfg->queue_msix_vector);
549 /* Flush the write out to device */
550 return vp_ioread16(addr: &cfg->queue_msix_vector);
551}
552EXPORT_SYMBOL_GPL(vp_modern_queue_vector);
553
554/*
555 * vp_modern_config_vector - set the vector for config interrupt
556 * @mdev: the modern virtio-pci device
557 * @vector: the config vector
558 *
559 * Returns the config vector read from the device
560 */
561u16 vp_modern_config_vector(struct virtio_pci_modern_device *mdev,
562 u16 vector)
563{
564 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
565
566 /* Setup the vector used for configuration events */
567 vp_iowrite16(value: vector, addr: &cfg->msix_config);
568 /* Verify we had enough resources to assign the vector */
569 /* Will also flush the write out to device */
570 return vp_ioread16(addr: &cfg->msix_config);
571}
572EXPORT_SYMBOL_GPL(vp_modern_config_vector);
573
574/*
575 * vp_modern_queue_address - set the virtqueue address
576 * @mdev: the modern virtio-pci device
577 * @index: the queue index
578 * @desc_addr: address of the descriptor area
579 * @driver_addr: address of the driver area
580 * @device_addr: address of the device area
581 */
582void vp_modern_queue_address(struct virtio_pci_modern_device *mdev,
583 u16 index, u64 desc_addr, u64 driver_addr,
584 u64 device_addr)
585{
586 struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
587
588 vp_iowrite16(value: index, addr: &cfg->queue_select);
589
590 vp_iowrite64_twopart(val: desc_addr, lo: &cfg->queue_desc_lo,
591 hi: &cfg->queue_desc_hi);
592 vp_iowrite64_twopart(val: driver_addr, lo: &cfg->queue_avail_lo,
593 hi: &cfg->queue_avail_hi);
594 vp_iowrite64_twopart(val: device_addr, lo: &cfg->queue_used_lo,
595 hi: &cfg->queue_used_hi);
596}
597EXPORT_SYMBOL_GPL(vp_modern_queue_address);
598
599/*
600 * vp_modern_set_queue_enable - enable a virtqueue
601 * @mdev: the modern virtio-pci device
602 * @index: the queue index
603 * @enable: whether the virtqueue is enable or not
604 */
605void vp_modern_set_queue_enable(struct virtio_pci_modern_device *mdev,
606 u16 index, bool enable)
607{
608 vp_iowrite16(value: index, addr: &mdev->common->queue_select);
609 vp_iowrite16(value: enable, addr: &mdev->common->queue_enable);
610}
611EXPORT_SYMBOL_GPL(vp_modern_set_queue_enable);
612
613/*
614 * vp_modern_get_queue_enable - enable a virtqueue
615 * @mdev: the modern virtio-pci device
616 * @index: the queue index
617 *
618 * Returns whether a virtqueue is enabled or not
619 */
620bool vp_modern_get_queue_enable(struct virtio_pci_modern_device *mdev,
621 u16 index)
622{
623 vp_iowrite16(value: index, addr: &mdev->common->queue_select);
624
625 return vp_ioread16(addr: &mdev->common->queue_enable);
626}
627EXPORT_SYMBOL_GPL(vp_modern_get_queue_enable);
628
629/*
630 * vp_modern_set_queue_size - set size for a virtqueue
631 * @mdev: the modern virtio-pci device
632 * @index: the queue index
633 * @size: the size of the virtqueue
634 */
635void vp_modern_set_queue_size(struct virtio_pci_modern_device *mdev,
636 u16 index, u16 size)
637{
638 vp_iowrite16(value: index, addr: &mdev->common->queue_select);
639 vp_iowrite16(value: size, addr: &mdev->common->queue_size);
640
641}
642EXPORT_SYMBOL_GPL(vp_modern_set_queue_size);
643
644/*
645 * vp_modern_get_queue_size - get size for a virtqueue
646 * @mdev: the modern virtio-pci device
647 * @index: the queue index
648 *
649 * Returns the size of the virtqueue
650 */
651u16 vp_modern_get_queue_size(struct virtio_pci_modern_device *mdev,
652 u16 index)
653{
654 vp_iowrite16(value: index, addr: &mdev->common->queue_select);
655
656 return vp_ioread16(addr: &mdev->common->queue_size);
657
658}
659EXPORT_SYMBOL_GPL(vp_modern_get_queue_size);
660
661/*
662 * vp_modern_get_num_queues - get the number of virtqueues
663 * @mdev: the modern virtio-pci device
664 *
665 * Returns the number of virtqueues
666 */
667u16 vp_modern_get_num_queues(struct virtio_pci_modern_device *mdev)
668{
669 return vp_ioread16(addr: &mdev->common->num_queues);
670}
671EXPORT_SYMBOL_GPL(vp_modern_get_num_queues);
672
673/*
674 * vp_modern_get_queue_notify_off - get notification offset for a virtqueue
675 * @mdev: the modern virtio-pci device
676 * @index: the queue index
677 *
678 * Returns the notification offset for a virtqueue
679 */
680static u16 vp_modern_get_queue_notify_off(struct virtio_pci_modern_device *mdev,
681 u16 index)
682{
683 vp_iowrite16(value: index, addr: &mdev->common->queue_select);
684
685 return vp_ioread16(addr: &mdev->common->queue_notify_off);
686}
687
688/*
689 * vp_modern_map_vq_notify - map notification area for a
690 * specific virtqueue
691 * @mdev: the modern virtio-pci device
692 * @index: the queue index
693 * @pa: the pointer to the physical address of the nofity area
694 *
695 * Returns the address of the notification area
696 */
697void __iomem *vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,
698 u16 index, resource_size_t *pa)
699{
700 u16 off = vp_modern_get_queue_notify_off(mdev, index);
701
702 if (mdev->notify_base) {
703 /* offset should not wrap */
704 if ((u64)off * mdev->notify_offset_multiplier + 2
705 > mdev->notify_len) {
706 dev_warn(&mdev->pci_dev->dev,
707 "bad notification offset %u (x %u) "
708 "for queue %u > %zd",
709 off, mdev->notify_offset_multiplier,
710 index, mdev->notify_len);
711 return NULL;
712 }
713 if (pa)
714 *pa = mdev->notify_pa +
715 off * mdev->notify_offset_multiplier;
716 return mdev->notify_base + off * mdev->notify_offset_multiplier;
717 } else {
718 return vp_modern_map_capability(mdev,
719 off: mdev->notify_map_cap, minlen: 2, align: 2,
720 start: off * mdev->notify_offset_multiplier, size: 2,
721 NULL, pa);
722 }
723}
724EXPORT_SYMBOL_GPL(vp_modern_map_vq_notify);
725
726u16 vp_modern_avq_num(struct virtio_pci_modern_device *mdev)
727{
728 struct virtio_pci_modern_common_cfg __iomem *cfg;
729
730 cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common;
731 return vp_ioread16(addr: &cfg->admin_queue_num);
732}
733EXPORT_SYMBOL_GPL(vp_modern_avq_num);
734
735u16 vp_modern_avq_index(struct virtio_pci_modern_device *mdev)
736{
737 struct virtio_pci_modern_common_cfg __iomem *cfg;
738
739 cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common;
740 return vp_ioread16(addr: &cfg->admin_queue_index);
741}
742EXPORT_SYMBOL_GPL(vp_modern_avq_index);
743
744MODULE_VERSION("0.1");
745MODULE_DESCRIPTION("Modern Virtio PCI Device");
746MODULE_AUTHOR("Jason Wang <jasowang@redhat.com>");
747MODULE_LICENSE("GPL");
748

source code of linux/drivers/virtio/virtio_pci_modern_dev.c