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, off + offsetof(struct virtio_pci_cap,
32						 bar),
33			     &bar);
34	pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, offset),
35			     &offset);
36	pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, length),
37			      &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, 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, pos + offsetof(struct virtio_pci_cap,
124							 cfg_type),
125				     &type);
126		pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap,
127							 bar),
128				     &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(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG,
257					    IORESOURCE_IO | IORESOURCE_MEM,
258					    &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(pci_dev, VIRTIO_PCI_CAP_ISR_CFG,
267					 IORESOURCE_IO | IORESOURCE_MEM,
268					 &mdev->modern_bars);
269	notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG,
270					    IORESOURCE_IO | IORESOURCE_MEM,
271					    &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(&pci_dev->dev,
280					mdev->dma_mask ? : DMA_BIT_MASK(64));
281	if (err)
282		err = dma_set_mask_and_coherent(&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(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG,
291					    IORESOURCE_IO | IORESOURCE_MEM,
292					    &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, common,
301			      sizeof(struct virtio_pci_common_cfg), 4, 0,
302			      offsetofend(struct virtio_pci_modern_common_cfg,
303					  admin_queue_num),
304			      &mdev->common_len, NULL);
305	if (!mdev->common)
306		goto err_map_common;
307	mdev->isr = vp_modern_map_capability(mdev, isr, sizeof(u8), 1,
308					     0, 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(pci_dev,
315			      notify + offsetof(struct virtio_pci_notify_cap,
316						notify_off_multiplier),
317			      &mdev->notify_offset_multiplier);
318	/* Read notify length and offset from config space. */
319	pci_read_config_dword(pci_dev,
320			      notify + offsetof(struct virtio_pci_notify_cap,
321						cap.length),
322			      &notify_length);
323
324	pci_read_config_dword(pci_dev,
325			      notify + offsetof(struct virtio_pci_notify_cap,
326						cap.offset),
327			      &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, notify,
335							     2, 2,
336							     0, notify_length,
337							     &mdev->notify_len,
338							     &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, device, 0, 4,
350							0, PAGE_SIZE,
351							&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(pci_dev, mdev->notify_base);
362err_map_notify:
363	pci_iounmap(pci_dev, mdev->isr);
364err_map_isr:
365	pci_iounmap(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(pci_dev, mdev->device);
382	if (mdev->notify_base)
383		pci_iounmap(pci_dev, mdev->notify_base);
384	pci_iounmap(pci_dev, mdev->isr);
385	pci_iounmap(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(0, &cfg->device_feature_select);
403	features = vp_ioread32(&cfg->device_feature);
404	vp_iowrite32(1, &cfg->device_feature_select);
405	features |= ((u64)vp_ioread32(&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(0, &cfg->guest_feature_select);
424	features = vp_ioread32(&cfg->guest_feature);
425	vp_iowrite32(1, &cfg->guest_feature_select);
426	features |= ((u64)vp_ioread32(&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(0, &cfg->guest_feature_select);
443	vp_iowrite32((u32)features, &cfg->guest_feature);
444	vp_iowrite32(1, &cfg->guest_feature_select);
445	vp_iowrite32(features >> 32, &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(&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(&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(status, &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(index, &cfg->cfg.queue_select);
508	return vp_ioread16(&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(index, &cfg->cfg.queue_select);
524	vp_iowrite16(1, &cfg->queue_reset);
525
526	while (vp_ioread16(&cfg->queue_reset))
527		msleep(1);
528
529	while (vp_ioread16(&cfg->cfg.queue_enable))
530		msleep(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(index, &cfg->queue_select);
548	vp_iowrite16(vector, &cfg->queue_msix_vector);
549	/* Flush the write out to device */
550	return vp_ioread16(&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(vector, &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(&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(index, &cfg->queue_select);
589
590	vp_iowrite64_twopart(desc_addr, &cfg->queue_desc_lo,
591			     &cfg->queue_desc_hi);
592	vp_iowrite64_twopart(driver_addr, &cfg->queue_avail_lo,
593			     &cfg->queue_avail_hi);
594	vp_iowrite64_twopart(device_addr, &cfg->queue_used_lo,
595			     &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(index, &mdev->common->queue_select);
609	vp_iowrite16(enable, &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(index, &mdev->common->queue_select);
624
625	return vp_ioread16(&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(index, &mdev->common->queue_select);
639	vp_iowrite16(size, &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(index, &mdev->common->queue_select);
655
656	return vp_ioread16(&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(&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(index, &mdev->common->queue_select);
684
685	return vp_ioread16(&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				       mdev->notify_map_cap, 2, 2,
720				       off * mdev->notify_offset_multiplier, 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(&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(&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