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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Virtio PCI driver - modern (virtio 1.0) device support
4 *
5 * This module allows virtio devices to be used over a virtual PCI device.
6 * This can be used with QEMU based VMMs like KVM or Xen.
7 *
8 * Copyright IBM Corp. 2007
9 * Copyright Red Hat, Inc. 2014
10 *
11 * Authors:
12 * Anthony Liguori <aliguori@us.ibm.com>
13 * Rusty Russell <rusty@rustcorp.com.au>
14 * Michael S. Tsirkin <mst@redhat.com>
15 */
16
17#include <linux/delay.h>
18#define VIRTIO_PCI_NO_LEGACY
19#include "virtio_pci_common.h"
20
21/*
22 * Type-safe wrappers for io accesses.
23 * Use these to enforce at compile time the following spec requirement:
24 *
25 * The driver MUST access each field using the “natural” access
26 * method, i.e. 32-bit accesses for 32-bit fields, 16-bit accesses
27 * for 16-bit fields and 8-bit accesses for 8-bit fields.
28 */
29static inline u8 vp_ioread8(u8 __iomem *addr)
30{
31 return ioread8(addr);
32}
33static inline u16 vp_ioread16 (__le16 __iomem *addr)
34{
35 return ioread16(addr);
36}
37
38static inline u32 vp_ioread32(__le32 __iomem *addr)
39{
40 return ioread32(addr);
41}
42
43static inline void vp_iowrite8(u8 value, u8 __iomem *addr)
44{
45 iowrite8(value, addr);
46}
47
48static inline void vp_iowrite16(u16 value, __le16 __iomem *addr)
49{
50 iowrite16(value, addr);
51}
52
53static inline void vp_iowrite32(u32 value, __le32 __iomem *addr)
54{
55 iowrite32(value, addr);
56}
57
58static void vp_iowrite64_twopart(u64 val,
59 __le32 __iomem *lo, __le32 __iomem *hi)
60{
61 vp_iowrite32((u32)val, lo);
62 vp_iowrite32(val >> 32, hi);
63}
64
65static void __iomem *map_capability(struct pci_dev *dev, int off,
66 size_t minlen,
67 u32 align,
68 u32 start, u32 size,
69 size_t *len)
70{
71 u8 bar;
72 u32 offset, length;
73 void __iomem *p;
74
75 pci_read_config_byte(dev, off + offsetof(struct virtio_pci_cap,
76 bar),
77 &bar);
78 pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, offset),
79 &offset);
80 pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, length),
81 &length);
82
83 if (length <= start) {
84 dev_err(&dev->dev,
85 "virtio_pci: bad capability len %u (>%u expected)\n",
86 length, start);
87 return NULL;
88 }
89
90 if (length - start < minlen) {
91 dev_err(&dev->dev,
92 "virtio_pci: bad capability len %u (>=%zu expected)\n",
93 length, minlen);
94 return NULL;
95 }
96
97 length -= start;
98
99 if (start + offset < offset) {
100 dev_err(&dev->dev,
101 "virtio_pci: map wrap-around %u+%u\n",
102 start, offset);
103 return NULL;
104 }
105
106 offset += start;
107
108 if (offset & (align - 1)) {
109 dev_err(&dev->dev,
110 "virtio_pci: offset %u not aligned to %u\n",
111 offset, align);
112 return NULL;
113 }
114
115 if (length > size)
116 length = size;
117
118 if (len)
119 *len = length;
120
121 if (minlen + offset < minlen ||
122 minlen + offset > pci_resource_len(dev, bar)) {
123 dev_err(&dev->dev,
124 "virtio_pci: map virtio %zu@%u "
125 "out of range on bar %i length %lu\n",
126 minlen, offset,
127 bar, (unsigned long)pci_resource_len(dev, bar));
128 return NULL;
129 }
130
131 p = pci_iomap_range(dev, bar, offset, length);
132 if (!p)
133 dev_err(&dev->dev,
134 "virtio_pci: unable to map virtio %u@%u on bar %i\n",
135 length, offset, bar);
136 return p;
137}
138
139/* virtio config->get_features() implementation */
140static u64 vp_get_features(struct virtio_device *vdev)
141{
142 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
143 u64 features;
144
145 vp_iowrite32(0, &vp_dev->common->device_feature_select);
146 features = vp_ioread32(&vp_dev->common->device_feature);
147 vp_iowrite32(1, &vp_dev->common->device_feature_select);
148 features |= ((u64)vp_ioread32(&vp_dev->common->device_feature) << 32);
149
150 return features;
151}
152
153static void vp_transport_features(struct virtio_device *vdev, u64 features)
154{
155 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
156 struct pci_dev *pci_dev = vp_dev->pci_dev;
157
158 if ((features & BIT_ULL(VIRTIO_F_SR_IOV)) &&
159 pci_find_ext_capability(pci_dev, PCI_EXT_CAP_ID_SRIOV))
160 __virtio_set_bit(vdev, VIRTIO_F_SR_IOV);
161}
162
163/* virtio config->finalize_features() implementation */
164static int vp_finalize_features(struct virtio_device *vdev)
165{
166 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
167 u64 features = vdev->features;
168
169 /* Give virtio_ring a chance to accept features. */
170 vring_transport_features(vdev);
171
172 /* Give virtio_pci a chance to accept features. */
173 vp_transport_features(vdev, features);
174
175 if (!__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
176 dev_err(&vdev->dev, "virtio: device uses modern interface "
177 "but does not have VIRTIO_F_VERSION_1\n");
178 return -EINVAL;
179 }
180
181 vp_iowrite32(0, &vp_dev->common->guest_feature_select);
182 vp_iowrite32((u32)vdev->features, &vp_dev->common->guest_feature);
183 vp_iowrite32(1, &vp_dev->common->guest_feature_select);
184 vp_iowrite32(vdev->features >> 32, &vp_dev->common->guest_feature);
185
186 return 0;
187}
188
189/* virtio config->get() implementation */
190static void vp_get(struct virtio_device *vdev, unsigned offset,
191 void *buf, unsigned len)
192{
193 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
194 u8 b;
195 __le16 w;
196 __le32 l;
197
198 BUG_ON(offset + len > vp_dev->device_len);
199
200 switch (len) {
201 case 1:
202 b = ioread8(vp_dev->device + offset);
203 memcpy(buf, &b, sizeof b);
204 break;
205 case 2:
206 w = cpu_to_le16(ioread16(vp_dev->device + offset));
207 memcpy(buf, &w, sizeof w);
208 break;
209 case 4:
210 l = cpu_to_le32(ioread32(vp_dev->device + offset));
211 memcpy(buf, &l, sizeof l);
212 break;
213 case 8:
214 l = cpu_to_le32(ioread32(vp_dev->device + offset));
215 memcpy(buf, &l, sizeof l);
216 l = cpu_to_le32(ioread32(vp_dev->device + offset + sizeof l));
217 memcpy(buf + sizeof l, &l, sizeof l);
218 break;
219 default:
220 BUG();
221 }
222}
223
224/* the config->set() implementation. it's symmetric to the config->get()
225 * implementation */
226static void vp_set(struct virtio_device *vdev, unsigned offset,
227 const void *buf, unsigned len)
228{
229 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
230 u8 b;
231 __le16 w;
232 __le32 l;
233
234 BUG_ON(offset + len > vp_dev->device_len);
235
236 switch (len) {
237 case 1:
238 memcpy(&b, buf, sizeof b);
239 iowrite8(b, vp_dev->device + offset);
240 break;
241 case 2:
242 memcpy(&w, buf, sizeof w);
243 iowrite16(le16_to_cpu(w), vp_dev->device + offset);
244 break;
245 case 4:
246 memcpy(&l, buf, sizeof l);
247 iowrite32(le32_to_cpu(l), vp_dev->device + offset);
248 break;
249 case 8:
250 memcpy(&l, buf, sizeof l);
251 iowrite32(le32_to_cpu(l), vp_dev->device + offset);
252 memcpy(&l, buf + sizeof l, sizeof l);
253 iowrite32(le32_to_cpu(l), vp_dev->device + offset + sizeof l);
254 break;
255 default:
256 BUG();
257 }
258}
259
260static u32 vp_generation(struct virtio_device *vdev)
261{
262 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
263 return vp_ioread8(&vp_dev->common->config_generation);
264}
265
266/* config->{get,set}_status() implementations */
267static u8 vp_get_status(struct virtio_device *vdev)
268{
269 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
270 return vp_ioread8(&vp_dev->common->device_status);
271}
272
273static void vp_set_status(struct virtio_device *vdev, u8 status)
274{
275 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
276 /* We should never be setting status to 0. */
277 BUG_ON(status == 0);
278 vp_iowrite8(status, &vp_dev->common->device_status);
279}
280
281static void vp_reset(struct virtio_device *vdev)
282{
283 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
284 /* 0 status means a reset. */
285 vp_iowrite8(0, &vp_dev->common->device_status);
286 /* After writing 0 to device_status, the driver MUST wait for a read of
287 * device_status to return 0 before reinitializing the device.
288 * This will flush out the status write, and flush in device writes,
289 * including MSI-X interrupts, if any.
290 */
291 while (vp_ioread8(&vp_dev->common->device_status))
292 msleep(1);
293 /* Flush pending VQ/configuration callbacks. */
294 vp_synchronize_vectors(vdev);
295}
296
297static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector)
298{
299 /* Setup the vector used for configuration events */
300 vp_iowrite16(vector, &vp_dev->common->msix_config);
301 /* Verify we had enough resources to assign the vector */
302 /* Will also flush the write out to device */
303 return vp_ioread16(&vp_dev->common->msix_config);
304}
305
306static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
307 struct virtio_pci_vq_info *info,
308 unsigned index,
309 void (*callback)(struct virtqueue *vq),
310 const char *name,
311 bool ctx,
312 u16 msix_vec)
313{
314 struct virtio_pci_common_cfg __iomem *cfg = vp_dev->common;
315 struct virtqueue *vq;
316 u16 num, off;
317 int err;
318
319 if (index >= vp_ioread16(&cfg->num_queues))
320 return ERR_PTR(-ENOENT);
321
322 /* Select the queue we're interested in */
323 vp_iowrite16(index, &cfg->queue_select);
324
325 /* Check if queue is either not available or already active. */
326 num = vp_ioread16(&cfg->queue_size);
327 if (!num || vp_ioread16(&cfg->queue_enable))
328 return ERR_PTR(-ENOENT);
329
330 if (num & (num - 1)) {
331 dev_warn(&vp_dev->pci_dev->dev, "bad queue size %u", num);
332 return ERR_PTR(-EINVAL);
333 }
334
335 /* get offset of notification word for this vq */
336 off = vp_ioread16(&cfg->queue_notify_off);
337
338 info->msix_vector = msix_vec;
339
340 /* create the vring */
341 vq = vring_create_virtqueue(index, num,
342 SMP_CACHE_BYTES, &vp_dev->vdev,
343 true, true, ctx,
344 vp_notify, callback, name);
345 if (!vq)
346 return ERR_PTR(-ENOMEM);
347
348 /* activate the queue */
349 vp_iowrite16(virtqueue_get_vring_size(vq), &cfg->queue_size);
350 vp_iowrite64_twopart(virtqueue_get_desc_addr(vq),
351 &cfg->queue_desc_lo, &cfg->queue_desc_hi);
352 vp_iowrite64_twopart(virtqueue_get_avail_addr(vq),
353 &cfg->queue_avail_lo, &cfg->queue_avail_hi);
354 vp_iowrite64_twopart(virtqueue_get_used_addr(vq),
355 &cfg->queue_used_lo, &cfg->queue_used_hi);
356
357 if (vp_dev->notify_base) {
358 /* offset should not wrap */
359 if ((u64)off * vp_dev->notify_offset_multiplier + 2
360 > vp_dev->notify_len) {
361 dev_warn(&vp_dev->pci_dev->dev,
362 "bad notification offset %u (x %u) "
363 "for queue %u > %zd",
364 off, vp_dev->notify_offset_multiplier,
365 index, vp_dev->notify_len);
366 err = -EINVAL;
367 goto err_map_notify;
368 }
369 vq->priv = (void __force *)vp_dev->notify_base +
370 off * vp_dev->notify_offset_multiplier;
371 } else {
372 vq->priv = (void __force *)map_capability(vp_dev->pci_dev,
373 vp_dev->notify_map_cap, 2, 2,
374 off * vp_dev->notify_offset_multiplier, 2,
375 NULL);
376 }
377
378 if (!vq->priv) {
379 err = -ENOMEM;
380 goto err_map_notify;
381 }
382
383 if (msix_vec != VIRTIO_MSI_NO_VECTOR) {
384 vp_iowrite16(msix_vec, &cfg->queue_msix_vector);
385 msix_vec = vp_ioread16(&cfg->queue_msix_vector);
386 if (msix_vec == VIRTIO_MSI_NO_VECTOR) {
387 err = -EBUSY;
388 goto err_assign_vector;
389 }
390 }
391
392 return vq;
393
394err_assign_vector:
395 if (!vp_dev->notify_base)
396 pci_iounmap(vp_dev->pci_dev, (void __iomem __force *)vq->priv);
397err_map_notify:
398 vring_del_virtqueue(vq);
399 return ERR_PTR(err);
400}
401
402static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned nvqs,
403 struct virtqueue *vqs[],
404 vq_callback_t *callbacks[],
405 const char * const names[], const bool *ctx,
406 struct irq_affinity *desc)
407{
408 struct virtio_pci_device *vp_dev = to_vp_device(vdev);
409 struct virtqueue *vq;
410 int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names, ctx, desc);
411
412 if (rc)
413 return rc;
414
415 /* Select and activate all queues. Has to be done last: once we do
416 * this, there's no way to go back except reset.
417 */
418 list_for_each_entry(vq, &vdev->vqs, list) {
419 vp_iowrite16(vq->index, &vp_dev->common->queue_select);
420 vp_iowrite16(1, &vp_dev->common->queue_enable);
421 }
422
423 return 0;
424}
425
426static void del_vq(struct virtio_pci_vq_info *info)
427{
428 struct virtqueue *vq = info->vq;
429 struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
430
431 vp_iowrite16(vq->index, &vp_dev->common->queue_select);
432
433 if (vp_dev->msix_enabled) {
434 vp_iowrite16(VIRTIO_MSI_NO_VECTOR,
435 &vp_dev->common->queue_msix_vector);
436 /* Flush the write out to device */
437 vp_ioread16(&vp_dev->common->queue_msix_vector);
438 }
439
440 if (!vp_dev->notify_base)
441 pci_iounmap(vp_dev->pci_dev, (void __force __iomem *)vq->priv);
442
443 vring_del_virtqueue(vq);
444}
445
446static const struct virtio_config_ops virtio_pci_config_nodev_ops = {
447 .get = NULL,
448 .set = NULL,
449 .generation = vp_generation,
450 .get_status = vp_get_status,
451 .set_status = vp_set_status,
452 .reset = vp_reset,
453 .find_vqs = vp_modern_find_vqs,
454 .del_vqs = vp_del_vqs,
455 .get_features = vp_get_features,
456 .finalize_features = vp_finalize_features,
457 .bus_name = vp_bus_name,
458 .set_vq_affinity = vp_set_vq_affinity,
459 .get_vq_affinity = vp_get_vq_affinity,
460};
461
462static const struct virtio_config_ops virtio_pci_config_ops = {
463 .get = vp_get,
464 .set = vp_set,
465 .generation = vp_generation,
466 .get_status = vp_get_status,
467 .set_status = vp_set_status,
468 .reset = vp_reset,
469 .find_vqs = vp_modern_find_vqs,
470 .del_vqs = vp_del_vqs,
471 .get_features = vp_get_features,
472 .finalize_features = vp_finalize_features,
473 .bus_name = vp_bus_name,
474 .set_vq_affinity = vp_set_vq_affinity,
475 .get_vq_affinity = vp_get_vq_affinity,
476};
477
478/**
479 * virtio_pci_find_capability - walk capabilities to find device info.
480 * @dev: the pci device
481 * @cfg_type: the VIRTIO_PCI_CAP_* value we seek
482 * @ioresource_types: IORESOURCE_MEM and/or IORESOURCE_IO.
483 *
484 * Returns offset of the capability, or 0.
485 */
486static inline int virtio_pci_find_capability(struct pci_dev *dev, u8 cfg_type,
487 u32 ioresource_types, int *bars)
488{
489 int pos;
490
491 for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR);
492 pos > 0;
493 pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) {
494 u8 type, bar;
495 pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap,
496 cfg_type),
497 &type);
498 pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap,
499 bar),
500 &bar);
501
502 /* Ignore structures with reserved BAR values */
503 if (bar > 0x5)
504 continue;
505
506 if (type == cfg_type) {
507 if (pci_resource_len(dev, bar) &&
508 pci_resource_flags(dev, bar) & ioresource_types) {
509 *bars |= (1 << bar);
510 return pos;
511 }
512 }
513 }
514 return 0;
515}
516
517/* This is part of the ABI. Don't screw with it. */
518static inline void check_offsets(void)
519{
520 /* Note: disk space was harmed in compilation of this function. */
521 BUILD_BUG_ON(VIRTIO_PCI_CAP_VNDR !=
522 offsetof(struct virtio_pci_cap, cap_vndr));
523 BUILD_BUG_ON(VIRTIO_PCI_CAP_NEXT !=
524 offsetof(struct virtio_pci_cap, cap_next));
525 BUILD_BUG_ON(VIRTIO_PCI_CAP_LEN !=
526 offsetof(struct virtio_pci_cap, cap_len));
527 BUILD_BUG_ON(VIRTIO_PCI_CAP_CFG_TYPE !=
528 offsetof(struct virtio_pci_cap, cfg_type));
529 BUILD_BUG_ON(VIRTIO_PCI_CAP_BAR !=
530 offsetof(struct virtio_pci_cap, bar));
531 BUILD_BUG_ON(VIRTIO_PCI_CAP_OFFSET !=
532 offsetof(struct virtio_pci_cap, offset));
533 BUILD_BUG_ON(VIRTIO_PCI_CAP_LENGTH !=
534 offsetof(struct virtio_pci_cap, length));
535 BUILD_BUG_ON(VIRTIO_PCI_NOTIFY_CAP_MULT !=
536 offsetof(struct virtio_pci_notify_cap,
537 notify_off_multiplier));
538 BUILD_BUG_ON(VIRTIO_PCI_COMMON_DFSELECT !=
539 offsetof(struct virtio_pci_common_cfg,
540 device_feature_select));
541 BUILD_BUG_ON(VIRTIO_PCI_COMMON_DF !=
542 offsetof(struct virtio_pci_common_cfg, device_feature));
543 BUILD_BUG_ON(VIRTIO_PCI_COMMON_GFSELECT !=
544 offsetof(struct virtio_pci_common_cfg,
545 guest_feature_select));
546 BUILD_BUG_ON(VIRTIO_PCI_COMMON_GF !=
547 offsetof(struct virtio_pci_common_cfg, guest_feature));
548 BUILD_BUG_ON(VIRTIO_PCI_COMMON_MSIX !=
549 offsetof(struct virtio_pci_common_cfg, msix_config));
550 BUILD_BUG_ON(VIRTIO_PCI_COMMON_NUMQ !=
551 offsetof(struct virtio_pci_common_cfg, num_queues));
552 BUILD_BUG_ON(VIRTIO_PCI_COMMON_STATUS !=
553 offsetof(struct virtio_pci_common_cfg, device_status));
554 BUILD_BUG_ON(VIRTIO_PCI_COMMON_CFGGENERATION !=
555 offsetof(struct virtio_pci_common_cfg, config_generation));
556 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SELECT !=
557 offsetof(struct virtio_pci_common_cfg, queue_select));
558 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SIZE !=
559 offsetof(struct virtio_pci_common_cfg, queue_size));
560 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_MSIX !=
561 offsetof(struct virtio_pci_common_cfg, queue_msix_vector));
562 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_ENABLE !=
563 offsetof(struct virtio_pci_common_cfg, queue_enable));
564 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NOFF !=
565 offsetof(struct virtio_pci_common_cfg, queue_notify_off));
566 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCLO !=
567 offsetof(struct virtio_pci_common_cfg, queue_desc_lo));
568 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCHI !=
569 offsetof(struct virtio_pci_common_cfg, queue_desc_hi));
570 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILLO !=
571 offsetof(struct virtio_pci_common_cfg, queue_avail_lo));
572 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILHI !=
573 offsetof(struct virtio_pci_common_cfg, queue_avail_hi));
574 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDLO !=
575 offsetof(struct virtio_pci_common_cfg, queue_used_lo));
576 BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDHI !=
577 offsetof(struct virtio_pci_common_cfg, queue_used_hi));
578}
579
580/* the PCI probing function */
581int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
582{
583 struct pci_dev *pci_dev = vp_dev->pci_dev;
584 int err, common, isr, notify, device;
585 u32 notify_length;
586 u32 notify_offset;
587
588 check_offsets();
589
590 /* We only own devices >= 0x1000 and <= 0x107f: leave the rest. */
591 if (pci_dev->device < 0x1000 || pci_dev->device > 0x107f)
592 return -ENODEV;
593
594 if (pci_dev->device < 0x1040) {
595 /* Transitional devices: use the PCI subsystem device id as
596 * virtio device id, same as legacy driver always did.
597 */
598 vp_dev->vdev.id.device = pci_dev->subsystem_device;
599 } else {
600 /* Modern devices: simply use PCI device id, but start from 0x1040. */
601 vp_dev->vdev.id.device = pci_dev->device - 0x1040;
602 }
603 vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
604
605 /* check for a common config: if not, use legacy mode (bar 0). */
606 common = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG,
607 IORESOURCE_IO | IORESOURCE_MEM,
608 &vp_dev->modern_bars);
609 if (!common) {
610 dev_info(&pci_dev->dev,
611 "virtio_pci: leaving for legacy driver\n");
612 return -ENODEV;
613 }
614
615 /* If common is there, these should be too... */
616 isr = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_ISR_CFG,
617 IORESOURCE_IO | IORESOURCE_MEM,
618 &vp_dev->modern_bars);
619 notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG,
620 IORESOURCE_IO | IORESOURCE_MEM,
621 &vp_dev->modern_bars);
622 if (!isr || !notify) {
623 dev_err(&pci_dev->dev,
624 "virtio_pci: missing capabilities %i/%i/%i\n",
625 common, isr, notify);
626 return -EINVAL;
627 }
628
629 err = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(64));
630 if (err)
631 err = dma_set_mask_and_coherent(&pci_dev->dev,
632 DMA_BIT_MASK(32));
633 if (err)
634 dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n");
635
636 /* Device capability is only mandatory for devices that have
637 * device-specific configuration.
638 */
639 device = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG,
640 IORESOURCE_IO | IORESOURCE_MEM,
641 &vp_dev->modern_bars);
642
643 err = pci_request_selected_regions(pci_dev, vp_dev->modern_bars,
644 "virtio-pci-modern");
645 if (err)
646 return err;
647
648 err = -EINVAL;
649 vp_dev->common = map_capability(pci_dev, common,
650 sizeof(struct virtio_pci_common_cfg), 4,
651 0, sizeof(struct virtio_pci_common_cfg),
652 NULL);
653 if (!vp_dev->common)
654 goto err_map_common;
655 vp_dev->isr = map_capability(pci_dev, isr, sizeof(u8), 1,
656 0, 1,
657 NULL);
658 if (!vp_dev->isr)
659 goto err_map_isr;
660
661 /* Read notify_off_multiplier from config space. */
662 pci_read_config_dword(pci_dev,
663 notify + offsetof(struct virtio_pci_notify_cap,
664 notify_off_multiplier),
665 &vp_dev->notify_offset_multiplier);
666 /* Read notify length and offset from config space. */
667 pci_read_config_dword(pci_dev,
668 notify + offsetof(struct virtio_pci_notify_cap,
669 cap.length),
670 ¬ify_length);
671
672 pci_read_config_dword(pci_dev,
673 notify + offsetof(struct virtio_pci_notify_cap,
674 cap.offset),
675 ¬ify_offset);
676
677 /* We don't know how many VQs we'll map, ahead of the time.
678 * If notify length is small, map it all now.
679 * Otherwise, map each VQ individually later.
680 */
681 if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) {
682 vp_dev->notify_base = map_capability(pci_dev, notify, 2, 2,
683 0, notify_length,
684 &vp_dev->notify_len);
685 if (!vp_dev->notify_base)
686 goto err_map_notify;
687 } else {
688 vp_dev->notify_map_cap = notify;
689 }
690
691 /* Again, we don't know how much we should map, but PAGE_SIZE
692 * is more than enough for all existing devices.
693 */
694 if (device) {
695 vp_dev->device = map_capability(pci_dev, device, 0, 4,
696 0, PAGE_SIZE,
697 &vp_dev->device_len);
698 if (!vp_dev->device)
699 goto err_map_device;
700
701 vp_dev->vdev.config = &virtio_pci_config_ops;
702 } else {
703 vp_dev->vdev.config = &virtio_pci_config_nodev_ops;
704 }
705
706 vp_dev->config_vector = vp_config_vector;
707 vp_dev->setup_vq = setup_vq;
708 vp_dev->del_vq = del_vq;
709
710 return 0;
711
712err_map_device:
713 if (vp_dev->notify_base)
714 pci_iounmap(pci_dev, vp_dev->notify_base);
715err_map_notify:
716 pci_iounmap(pci_dev, vp_dev->isr);
717err_map_isr:
718 pci_iounmap(pci_dev, vp_dev->common);
719err_map_common:
720 return err;
721}
722
723void virtio_pci_modern_remove(struct virtio_pci_device *vp_dev)
724{
725 struct pci_dev *pci_dev = vp_dev->pci_dev;
726
727 if (vp_dev->device)
728 pci_iounmap(pci_dev, vp_dev->device);
729 if (vp_dev->notify_base)
730 pci_iounmap(pci_dev, vp_dev->notify_base);
731 pci_iounmap(pci_dev, vp_dev->isr);
732 pci_iounmap(pci_dev, vp_dev->common);
733 pci_release_selected_regions(pci_dev, vp_dev->modern_bars);
734}