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14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/cdev.h>
17#include <linux/device.h>
18#include <linux/mm.h>
19#include <linux/iommu.h>
20#include <linux/uuid.h>
21#include <linux/vdpa.h>
22#include <linux/nospec.h>
23#include <linux/vhost.h>
24#include <linux/virtio_net.h>
25#include <linux/kernel.h>
26
27#include "vhost.h"
28
29enum {
30 VHOST_VDPA_BACKEND_FEATURES =
31 (1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2) |
32 (1ULL << VHOST_BACKEND_F_IOTLB_BATCH),
33};
34
35#define VHOST_VDPA_DEV_MAX (1U << MINORBITS)
36
37struct vhost_vdpa {
38 struct vhost_dev vdev;
39 struct iommu_domain *domain;
40 struct vhost_virtqueue *vqs;
41 struct completion completion;
42 struct vdpa_device *vdpa;
43 struct device dev;
44 struct cdev cdev;
45 atomic_t opened;
46 int nvqs;
47 int virtio_id;
48 int minor;
49 struct eventfd_ctx *config_ctx;
50 int in_batch;
51};
52
53static DEFINE_IDA(vhost_vdpa_ida);
54
55static dev_t vhost_vdpa_major;
56
57static void handle_vq_kick(struct vhost_work *work)
58{
59 struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
60 poll.work);
61 struct vhost_vdpa *v = container_of(vq->dev, struct vhost_vdpa, vdev);
62 const struct vdpa_config_ops *ops = v->vdpa->config;
63
64 ops->kick_vq(v->vdpa, vq - v->vqs);
65}
66
67static irqreturn_t vhost_vdpa_virtqueue_cb(void *private)
68{
69 struct vhost_virtqueue *vq = private;
70 struct eventfd_ctx *call_ctx = vq->call_ctx.ctx;
71
72 if (call_ctx)
73 eventfd_signal(call_ctx, 1);
74
75 return IRQ_HANDLED;
76}
77
78static irqreturn_t vhost_vdpa_config_cb(void *private)
79{
80 struct vhost_vdpa *v = private;
81 struct eventfd_ctx *config_ctx = v->config_ctx;
82
83 if (config_ctx)
84 eventfd_signal(config_ctx, 1);
85
86 return IRQ_HANDLED;
87}
88
89static void vhost_vdpa_setup_vq_irq(struct vhost_vdpa *v, u16 qid)
90{
91 struct vhost_virtqueue *vq = &v->vqs[qid];
92 const struct vdpa_config_ops *ops = v->vdpa->config;
93 struct vdpa_device *vdpa = v->vdpa;
94 int ret, irq;
95
96 if (!ops->get_vq_irq)
97 return;
98
99 irq = ops->get_vq_irq(vdpa, qid);
100 spin_lock(&vq->call_ctx.ctx_lock);
101 irq_bypass_unregister_producer(&vq->call_ctx.producer);
102 if (!vq->call_ctx.ctx || irq < 0) {
103 spin_unlock(&vq->call_ctx.ctx_lock);
104 return;
105 }
106
107 vq->call_ctx.producer.token = vq->call_ctx.ctx;
108 vq->call_ctx.producer.irq = irq;
109 ret = irq_bypass_register_producer(&vq->call_ctx.producer);
110 spin_unlock(&vq->call_ctx.ctx_lock);
111}
112
113static void vhost_vdpa_unsetup_vq_irq(struct vhost_vdpa *v, u16 qid)
114{
115 struct vhost_virtqueue *vq = &v->vqs[qid];
116
117 spin_lock(&vq->call_ctx.ctx_lock);
118 irq_bypass_unregister_producer(&vq->call_ctx.producer);
119 spin_unlock(&vq->call_ctx.ctx_lock);
120}
121
122static void vhost_vdpa_reset(struct vhost_vdpa *v)
123{
124 struct vdpa_device *vdpa = v->vdpa;
125
126 vdpa_reset(vdpa);
127 v->in_batch = 0;
128}
129
130static long vhost_vdpa_get_device_id(struct vhost_vdpa *v, u8 __user *argp)
131{
132 struct vdpa_device *vdpa = v->vdpa;
133 const struct vdpa_config_ops *ops = vdpa->config;
134 u32 device_id;
135
136 device_id = ops->get_device_id(vdpa);
137
138 if (copy_to_user(argp, &device_id, sizeof(device_id)))
139 return -EFAULT;
140
141 return 0;
142}
143
144static long vhost_vdpa_get_status(struct vhost_vdpa *v, u8 __user *statusp)
145{
146 struct vdpa_device *vdpa = v->vdpa;
147 const struct vdpa_config_ops *ops = vdpa->config;
148 u8 status;
149
150 status = ops->get_status(vdpa);
151
152 if (copy_to_user(statusp, &status, sizeof(status)))
153 return -EFAULT;
154
155 return 0;
156}
157
158static long vhost_vdpa_set_status(struct vhost_vdpa *v, u8 __user *statusp)
159{
160 struct vdpa_device *vdpa = v->vdpa;
161 const struct vdpa_config_ops *ops = vdpa->config;
162 u8 status, status_old;
163 int nvqs = v->nvqs;
164 u16 i;
165
166 if (copy_from_user(&status, statusp, sizeof(status)))
167 return -EFAULT;
168
169 status_old = ops->get_status(vdpa);
170
171
172
173
174
175 if (status != 0 && (ops->get_status(vdpa) & ~status) != 0)
176 return -EINVAL;
177
178 ops->set_status(vdpa, status);
179
180 if ((status & VIRTIO_CONFIG_S_DRIVER_OK) && !(status_old & VIRTIO_CONFIG_S_DRIVER_OK))
181 for (i = 0; i < nvqs; i++)
182 vhost_vdpa_setup_vq_irq(v, i);
183
184 if ((status_old & VIRTIO_CONFIG_S_DRIVER_OK) && !(status & VIRTIO_CONFIG_S_DRIVER_OK))
185 for (i = 0; i < nvqs; i++)
186 vhost_vdpa_unsetup_vq_irq(v, i);
187
188 return 0;
189}
190
191static int vhost_vdpa_config_validate(struct vhost_vdpa *v,
192 struct vhost_vdpa_config *c)
193{
194 long size = 0;
195
196 switch (v->virtio_id) {
197 case VIRTIO_ID_NET:
198 size = sizeof(struct virtio_net_config);
199 break;
200 }
201
202 if (c->len == 0)
203 return -EINVAL;
204
205 if (c->len > size - c->off)
206 return -E2BIG;
207
208 return 0;
209}
210
211static long vhost_vdpa_get_config(struct vhost_vdpa *v,
212 struct vhost_vdpa_config __user *c)
213{
214 struct vdpa_device *vdpa = v->vdpa;
215 struct vhost_vdpa_config config;
216 unsigned long size = offsetof(struct vhost_vdpa_config, buf);
217 u8 *buf;
218
219 if (copy_from_user(&config, c, size))
220 return -EFAULT;
221 if (vhost_vdpa_config_validate(v, &config))
222 return -EINVAL;
223 buf = kvzalloc(config.len, GFP_KERNEL);
224 if (!buf)
225 return -ENOMEM;
226
227 vdpa_get_config(vdpa, config.off, buf, config.len);
228
229 if (copy_to_user(c->buf, buf, config.len)) {
230 kvfree(buf);
231 return -EFAULT;
232 }
233
234 kvfree(buf);
235 return 0;
236}
237
238static long vhost_vdpa_set_config(struct vhost_vdpa *v,
239 struct vhost_vdpa_config __user *c)
240{
241 struct vdpa_device *vdpa = v->vdpa;
242 const struct vdpa_config_ops *ops = vdpa->config;
243 struct vhost_vdpa_config config;
244 unsigned long size = offsetof(struct vhost_vdpa_config, buf);
245 u8 *buf;
246
247 if (copy_from_user(&config, c, size))
248 return -EFAULT;
249 if (vhost_vdpa_config_validate(v, &config))
250 return -EINVAL;
251 buf = kvzalloc(config.len, GFP_KERNEL);
252 if (!buf)
253 return -ENOMEM;
254
255 if (copy_from_user(buf, c->buf, config.len)) {
256 kvfree(buf);
257 return -EFAULT;
258 }
259
260 ops->set_config(vdpa, config.off, buf, config.len);
261
262 kvfree(buf);
263 return 0;
264}
265
266static long vhost_vdpa_get_features(struct vhost_vdpa *v, u64 __user *featurep)
267{
268 struct vdpa_device *vdpa = v->vdpa;
269 const struct vdpa_config_ops *ops = vdpa->config;
270 u64 features;
271
272 features = ops->get_features(vdpa);
273
274 if (copy_to_user(featurep, &features, sizeof(features)))
275 return -EFAULT;
276
277 return 0;
278}
279
280static long vhost_vdpa_set_features(struct vhost_vdpa *v, u64 __user *featurep)
281{
282 struct vdpa_device *vdpa = v->vdpa;
283 const struct vdpa_config_ops *ops = vdpa->config;
284 u64 features;
285
286
287
288
289
290 if (ops->get_status(vdpa) & VIRTIO_CONFIG_S_FEATURES_OK)
291 return -EBUSY;
292
293 if (copy_from_user(&features, featurep, sizeof(features)))
294 return -EFAULT;
295
296 if (vdpa_set_features(vdpa, features))
297 return -EINVAL;
298
299 return 0;
300}
301
302static long vhost_vdpa_get_vring_num(struct vhost_vdpa *v, u16 __user *argp)
303{
304 struct vdpa_device *vdpa = v->vdpa;
305 const struct vdpa_config_ops *ops = vdpa->config;
306 u16 num;
307
308 num = ops->get_vq_num_max(vdpa);
309
310 if (copy_to_user(argp, &num, sizeof(num)))
311 return -EFAULT;
312
313 return 0;
314}
315
316static void vhost_vdpa_config_put(struct vhost_vdpa *v)
317{
318 if (v->config_ctx)
319 eventfd_ctx_put(v->config_ctx);
320}
321
322static long vhost_vdpa_set_config_call(struct vhost_vdpa *v, u32 __user *argp)
323{
324 struct vdpa_callback cb;
325 int fd;
326 struct eventfd_ctx *ctx;
327
328 cb.callback = vhost_vdpa_config_cb;
329 cb.private = v->vdpa;
330 if (copy_from_user(&fd, argp, sizeof(fd)))
331 return -EFAULT;
332
333 ctx = fd == VHOST_FILE_UNBIND ? NULL : eventfd_ctx_fdget(fd);
334 swap(ctx, v->config_ctx);
335
336 if (!IS_ERR_OR_NULL(ctx))
337 eventfd_ctx_put(ctx);
338
339 if (IS_ERR(v->config_ctx))
340 return PTR_ERR(v->config_ctx);
341
342 v->vdpa->config->set_config_cb(v->vdpa, &cb);
343
344 return 0;
345}
346
347static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
348 void __user *argp)
349{
350 struct vdpa_device *vdpa = v->vdpa;
351 const struct vdpa_config_ops *ops = vdpa->config;
352 struct vdpa_vq_state vq_state;
353 struct vdpa_callback cb;
354 struct vhost_virtqueue *vq;
355 struct vhost_vring_state s;
356 u32 idx;
357 long r;
358
359 r = get_user(idx, (u32 __user *)argp);
360 if (r < 0)
361 return r;
362
363 if (idx >= v->nvqs)
364 return -ENOBUFS;
365
366 idx = array_index_nospec(idx, v->nvqs);
367 vq = &v->vqs[idx];
368
369 switch (cmd) {
370 case VHOST_VDPA_SET_VRING_ENABLE:
371 if (copy_from_user(&s, argp, sizeof(s)))
372 return -EFAULT;
373 ops->set_vq_ready(vdpa, idx, s.num);
374 return 0;
375 case VHOST_GET_VRING_BASE:
376 r = ops->get_vq_state(v->vdpa, idx, &vq_state);
377 if (r)
378 return r;
379
380 vq->last_avail_idx = vq_state.avail_index;
381 break;
382 }
383
384 r = vhost_vring_ioctl(&v->vdev, cmd, argp);
385 if (r)
386 return r;
387
388 switch (cmd) {
389 case VHOST_SET_VRING_ADDR:
390 if (ops->set_vq_address(vdpa, idx,
391 (u64)(uintptr_t)vq->desc,
392 (u64)(uintptr_t)vq->avail,
393 (u64)(uintptr_t)vq->used))
394 r = -EINVAL;
395 break;
396
397 case VHOST_SET_VRING_BASE:
398 vq_state.avail_index = vq->last_avail_idx;
399 if (ops->set_vq_state(vdpa, idx, &vq_state))
400 r = -EINVAL;
401 break;
402
403 case VHOST_SET_VRING_CALL:
404 if (vq->call_ctx.ctx) {
405 cb.callback = vhost_vdpa_virtqueue_cb;
406 cb.private = vq;
407 } else {
408 cb.callback = NULL;
409 cb.private = NULL;
410 }
411 ops->set_vq_cb(vdpa, idx, &cb);
412 vhost_vdpa_setup_vq_irq(v, idx);
413 break;
414
415 case VHOST_SET_VRING_NUM:
416 ops->set_vq_num(vdpa, idx, vq->num);
417 break;
418 }
419
420 return r;
421}
422
423static long vhost_vdpa_unlocked_ioctl(struct file *filep,
424 unsigned int cmd, unsigned long arg)
425{
426 struct vhost_vdpa *v = filep->private_data;
427 struct vhost_dev *d = &v->vdev;
428 void __user *argp = (void __user *)arg;
429 u64 __user *featurep = argp;
430 u64 features;
431 long r;
432
433 if (cmd == VHOST_SET_BACKEND_FEATURES) {
434 r = copy_from_user(&features, featurep, sizeof(features));
435 if (r)
436 return r;
437 if (features & ~VHOST_VDPA_BACKEND_FEATURES)
438 return -EOPNOTSUPP;
439 vhost_set_backend_features(&v->vdev, features);
440 return 0;
441 }
442
443 mutex_lock(&d->mutex);
444
445 switch (cmd) {
446 case VHOST_VDPA_GET_DEVICE_ID:
447 r = vhost_vdpa_get_device_id(v, argp);
448 break;
449 case VHOST_VDPA_GET_STATUS:
450 r = vhost_vdpa_get_status(v, argp);
451 break;
452 case VHOST_VDPA_SET_STATUS:
453 r = vhost_vdpa_set_status(v, argp);
454 break;
455 case VHOST_VDPA_GET_CONFIG:
456 r = vhost_vdpa_get_config(v, argp);
457 break;
458 case VHOST_VDPA_SET_CONFIG:
459 r = vhost_vdpa_set_config(v, argp);
460 break;
461 case VHOST_GET_FEATURES:
462 r = vhost_vdpa_get_features(v, argp);
463 break;
464 case VHOST_SET_FEATURES:
465 r = vhost_vdpa_set_features(v, argp);
466 break;
467 case VHOST_VDPA_GET_VRING_NUM:
468 r = vhost_vdpa_get_vring_num(v, argp);
469 break;
470 case VHOST_SET_LOG_BASE:
471 case VHOST_SET_LOG_FD:
472 r = -ENOIOCTLCMD;
473 break;
474 case VHOST_VDPA_SET_CONFIG_CALL:
475 r = vhost_vdpa_set_config_call(v, argp);
476 break;
477 case VHOST_GET_BACKEND_FEATURES:
478 features = VHOST_VDPA_BACKEND_FEATURES;
479 r = copy_to_user(featurep, &features, sizeof(features));
480 break;
481 default:
482 r = vhost_dev_ioctl(&v->vdev, cmd, argp);
483 if (r == -ENOIOCTLCMD)
484 r = vhost_vdpa_vring_ioctl(v, cmd, argp);
485 break;
486 }
487
488 mutex_unlock(&d->mutex);
489 return r;
490}
491
492static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last)
493{
494 struct vhost_dev *dev = &v->vdev;
495 struct vhost_iotlb *iotlb = dev->iotlb;
496 struct vhost_iotlb_map *map;
497 struct page *page;
498 unsigned long pfn, pinned;
499
500 while ((map = vhost_iotlb_itree_first(iotlb, start, last)) != NULL) {
501 pinned = map->size >> PAGE_SHIFT;
502 for (pfn = map->addr >> PAGE_SHIFT;
503 pinned > 0; pfn++, pinned--) {
504 page = pfn_to_page(pfn);
505 if (map->perm & VHOST_ACCESS_WO)
506 set_page_dirty_lock(page);
507 unpin_user_page(page);
508 }
509 atomic64_sub(map->size >> PAGE_SHIFT, &dev->mm->pinned_vm);
510 vhost_iotlb_map_free(iotlb, map);
511 }
512}
513
514static void vhost_vdpa_iotlb_free(struct vhost_vdpa *v)
515{
516 struct vhost_dev *dev = &v->vdev;
517
518 vhost_vdpa_iotlb_unmap(v, 0ULL, 0ULL - 1);
519 kfree(dev->iotlb);
520 dev->iotlb = NULL;
521}
522
523static int perm_to_iommu_flags(u32 perm)
524{
525 int flags = 0;
526
527 switch (perm) {
528 case VHOST_ACCESS_WO:
529 flags |= IOMMU_WRITE;
530 break;
531 case VHOST_ACCESS_RO:
532 flags |= IOMMU_READ;
533 break;
534 case VHOST_ACCESS_RW:
535 flags |= (IOMMU_WRITE | IOMMU_READ);
536 break;
537 default:
538 WARN(1, "invalidate vhost IOTLB permission\n");
539 break;
540 }
541
542 return flags | IOMMU_CACHE;
543}
544
545static int vhost_vdpa_map(struct vhost_vdpa *v,
546 u64 iova, u64 size, u64 pa, u32 perm)
547{
548 struct vhost_dev *dev = &v->vdev;
549 struct vdpa_device *vdpa = v->vdpa;
550 const struct vdpa_config_ops *ops = vdpa->config;
551 int r = 0;
552
553 r = vhost_iotlb_add_range(dev->iotlb, iova, iova + size - 1,
554 pa, perm);
555 if (r)
556 return r;
557
558 if (ops->dma_map) {
559 r = ops->dma_map(vdpa, iova, size, pa, perm);
560 } else if (ops->set_map) {
561 if (!v->in_batch)
562 r = ops->set_map(vdpa, dev->iotlb);
563 } else {
564 r = iommu_map(v->domain, iova, pa, size,
565 perm_to_iommu_flags(perm));
566 }
567
568 if (r)
569 vhost_iotlb_del_range(dev->iotlb, iova, iova + size - 1);
570
571 return r;
572}
573
574static void vhost_vdpa_unmap(struct vhost_vdpa *v, u64 iova, u64 size)
575{
576 struct vhost_dev *dev = &v->vdev;
577 struct vdpa_device *vdpa = v->vdpa;
578 const struct vdpa_config_ops *ops = vdpa->config;
579
580 vhost_vdpa_iotlb_unmap(v, iova, iova + size - 1);
581
582 if (ops->dma_map) {
583 ops->dma_unmap(vdpa, iova, size);
584 } else if (ops->set_map) {
585 if (!v->in_batch)
586 ops->set_map(vdpa, dev->iotlb);
587 } else {
588 iommu_unmap(v->domain, iova, size);
589 }
590}
591
592static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
593 struct vhost_iotlb_msg *msg)
594{
595 struct vhost_dev *dev = &v->vdev;
596 struct vhost_iotlb *iotlb = dev->iotlb;
597 struct page **page_list;
598 struct vm_area_struct **vmas;
599 unsigned int gup_flags = FOLL_LONGTERM;
600 unsigned long map_pfn, last_pfn = 0;
601 unsigned long npages, lock_limit;
602 unsigned long i, nmap = 0;
603 u64 iova = msg->iova;
604 long pinned;
605 int ret = 0;
606
607 if (vhost_iotlb_itree_first(iotlb, msg->iova,
608 msg->iova + msg->size - 1))
609 return -EEXIST;
610
611 if (msg->perm & VHOST_ACCESS_WO)
612 gup_flags |= FOLL_WRITE;
613
614 npages = PAGE_ALIGN(msg->size + (iova & ~PAGE_MASK)) >> PAGE_SHIFT;
615 if (!npages)
616 return -EINVAL;
617
618 page_list = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
619 vmas = kvmalloc_array(npages, sizeof(struct vm_area_struct *),
620 GFP_KERNEL);
621 if (!page_list || !vmas) {
622 ret = -ENOMEM;
623 goto free;
624 }
625
626 mmap_read_lock(dev->mm);
627
628 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
629 if (npages + atomic64_read(&dev->mm->pinned_vm) > lock_limit) {
630 ret = -ENOMEM;
631 goto unlock;
632 }
633
634 pinned = pin_user_pages(msg->uaddr & PAGE_MASK, npages, gup_flags,
635 page_list, vmas);
636 if (npages != pinned) {
637 if (pinned < 0) {
638 ret = pinned;
639 } else {
640 unpin_user_pages(page_list, pinned);
641 ret = -ENOMEM;
642 }
643 goto unlock;
644 }
645
646 iova &= PAGE_MASK;
647 map_pfn = page_to_pfn(page_list[0]);
648
649
650 for (i = 0; i <= npages; i++) {
651 unsigned long this_pfn;
652 u64 csize;
653
654
655 this_pfn = i < npages ? page_to_pfn(page_list[i]) : -1UL;
656
657 if (last_pfn && (this_pfn == -1UL ||
658 this_pfn != last_pfn + 1)) {
659
660 csize = last_pfn - map_pfn + 1;
661 ret = vhost_vdpa_map(v, iova, csize << PAGE_SHIFT,
662 map_pfn << PAGE_SHIFT,
663 msg->perm);
664 if (ret) {
665
666
667
668
669
670
671
672
673
674
675
676
677 unpin_user_pages(&page_list[nmap],
678 npages - nmap);
679 goto out;
680 }
681 atomic64_add(csize, &dev->mm->pinned_vm);
682 nmap += csize;
683 iova += csize << PAGE_SHIFT;
684 map_pfn = this_pfn;
685 }
686 last_pfn = this_pfn;
687 }
688
689 WARN_ON(nmap != npages);
690out:
691 if (ret)
692 vhost_vdpa_unmap(v, msg->iova, msg->size);
693unlock:
694 mmap_read_unlock(dev->mm);
695free:
696 kvfree(vmas);
697 kvfree(page_list);
698 return ret;
699}
700
701static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev,
702 struct vhost_iotlb_msg *msg)
703{
704 struct vhost_vdpa *v = container_of(dev, struct vhost_vdpa, vdev);
705 struct vdpa_device *vdpa = v->vdpa;
706 const struct vdpa_config_ops *ops = vdpa->config;
707 int r = 0;
708
709 r = vhost_dev_check_owner(dev);
710 if (r)
711 return r;
712
713 switch (msg->type) {
714 case VHOST_IOTLB_UPDATE:
715 r = vhost_vdpa_process_iotlb_update(v, msg);
716 break;
717 case VHOST_IOTLB_INVALIDATE:
718 vhost_vdpa_unmap(v, msg->iova, msg->size);
719 break;
720 case VHOST_IOTLB_BATCH_BEGIN:
721 v->in_batch = true;
722 break;
723 case VHOST_IOTLB_BATCH_END:
724 if (v->in_batch && ops->set_map)
725 ops->set_map(vdpa, dev->iotlb);
726 v->in_batch = false;
727 break;
728 default:
729 r = -EINVAL;
730 break;
731 }
732
733 return r;
734}
735
736static ssize_t vhost_vdpa_chr_write_iter(struct kiocb *iocb,
737 struct iov_iter *from)
738{
739 struct file *file = iocb->ki_filp;
740 struct vhost_vdpa *v = file->private_data;
741 struct vhost_dev *dev = &v->vdev;
742
743 return vhost_chr_write_iter(dev, from);
744}
745
746static int vhost_vdpa_alloc_domain(struct vhost_vdpa *v)
747{
748 struct vdpa_device *vdpa = v->vdpa;
749 const struct vdpa_config_ops *ops = vdpa->config;
750 struct device *dma_dev = vdpa_get_dma_dev(vdpa);
751 struct bus_type *bus;
752 int ret;
753
754
755 if (ops->set_map || ops->dma_map)
756 return 0;
757
758 bus = dma_dev->bus;
759 if (!bus)
760 return -EFAULT;
761
762 if (!iommu_capable(bus, IOMMU_CAP_CACHE_COHERENCY))
763 return -ENOTSUPP;
764
765 v->domain = iommu_domain_alloc(bus);
766 if (!v->domain)
767 return -EIO;
768
769 ret = iommu_attach_device(v->domain, dma_dev);
770 if (ret)
771 goto err_attach;
772
773 return 0;
774
775err_attach:
776 iommu_domain_free(v->domain);
777 return ret;
778}
779
780static void vhost_vdpa_free_domain(struct vhost_vdpa *v)
781{
782 struct vdpa_device *vdpa = v->vdpa;
783 struct device *dma_dev = vdpa_get_dma_dev(vdpa);
784
785 if (v->domain) {
786 iommu_detach_device(v->domain, dma_dev);
787 iommu_domain_free(v->domain);
788 }
789
790 v->domain = NULL;
791}
792
793static int vhost_vdpa_open(struct inode *inode, struct file *filep)
794{
795 struct vhost_vdpa *v;
796 struct vhost_dev *dev;
797 struct vhost_virtqueue **vqs;
798 int nvqs, i, r, opened;
799
800 v = container_of(inode->i_cdev, struct vhost_vdpa, cdev);
801
802 opened = atomic_cmpxchg(&v->opened, 0, 1);
803 if (opened)
804 return -EBUSY;
805
806 nvqs = v->nvqs;
807 vhost_vdpa_reset(v);
808
809 vqs = kmalloc_array(nvqs, sizeof(*vqs), GFP_KERNEL);
810 if (!vqs) {
811 r = -ENOMEM;
812 goto err;
813 }
814
815 dev = &v->vdev;
816 for (i = 0; i < nvqs; i++) {
817 vqs[i] = &v->vqs[i];
818 vqs[i]->handle_kick = handle_vq_kick;
819 }
820 vhost_dev_init(dev, vqs, nvqs, 0, 0, 0, false,
821 vhost_vdpa_process_iotlb_msg);
822
823 dev->iotlb = vhost_iotlb_alloc(0, 0);
824 if (!dev->iotlb) {
825 r = -ENOMEM;
826 goto err_init_iotlb;
827 }
828
829 r = vhost_vdpa_alloc_domain(v);
830 if (r)
831 goto err_init_iotlb;
832
833 filep->private_data = v;
834
835 return 0;
836
837err_init_iotlb:
838 vhost_dev_cleanup(&v->vdev);
839 kfree(vqs);
840err:
841 atomic_dec(&v->opened);
842 return r;
843}
844
845static void vhost_vdpa_clean_irq(struct vhost_vdpa *v)
846{
847 struct vhost_virtqueue *vq;
848 int i;
849
850 for (i = 0; i < v->nvqs; i++) {
851 vq = &v->vqs[i];
852 if (vq->call_ctx.producer.irq)
853 irq_bypass_unregister_producer(&vq->call_ctx.producer);
854 }
855}
856
857static int vhost_vdpa_release(struct inode *inode, struct file *filep)
858{
859 struct vhost_vdpa *v = filep->private_data;
860 struct vhost_dev *d = &v->vdev;
861
862 mutex_lock(&d->mutex);
863 filep->private_data = NULL;
864 vhost_vdpa_reset(v);
865 vhost_dev_stop(&v->vdev);
866 vhost_vdpa_iotlb_free(v);
867 vhost_vdpa_free_domain(v);
868 vhost_vdpa_config_put(v);
869 vhost_vdpa_clean_irq(v);
870 vhost_dev_cleanup(&v->vdev);
871 kfree(v->vdev.vqs);
872 mutex_unlock(&d->mutex);
873
874 atomic_dec(&v->opened);
875 complete(&v->completion);
876
877 return 0;
878}
879
880#ifdef CONFIG_MMU
881static vm_fault_t vhost_vdpa_fault(struct vm_fault *vmf)
882{
883 struct vhost_vdpa *v = vmf->vma->vm_file->private_data;
884 struct vdpa_device *vdpa = v->vdpa;
885 const struct vdpa_config_ops *ops = vdpa->config;
886 struct vdpa_notification_area notify;
887 struct vm_area_struct *vma = vmf->vma;
888 u16 index = vma->vm_pgoff;
889
890 notify = ops->get_vq_notification(vdpa, index);
891
892 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
893 if (remap_pfn_range(vma, vmf->address & PAGE_MASK,
894 notify.addr >> PAGE_SHIFT, PAGE_SIZE,
895 vma->vm_page_prot))
896 return VM_FAULT_SIGBUS;
897
898 return VM_FAULT_NOPAGE;
899}
900
901static const struct vm_operations_struct vhost_vdpa_vm_ops = {
902 .fault = vhost_vdpa_fault,
903};
904
905static int vhost_vdpa_mmap(struct file *file, struct vm_area_struct *vma)
906{
907 struct vhost_vdpa *v = vma->vm_file->private_data;
908 struct vdpa_device *vdpa = v->vdpa;
909 const struct vdpa_config_ops *ops = vdpa->config;
910 struct vdpa_notification_area notify;
911 unsigned long index = vma->vm_pgoff;
912
913 if (vma->vm_end - vma->vm_start != PAGE_SIZE)
914 return -EINVAL;
915 if ((vma->vm_flags & VM_SHARED) == 0)
916 return -EINVAL;
917 if (vma->vm_flags & VM_READ)
918 return -EINVAL;
919 if (index > 65535)
920 return -EINVAL;
921 if (!ops->get_vq_notification)
922 return -ENOTSUPP;
923
924
925
926
927
928 notify = ops->get_vq_notification(vdpa, index);
929 if (notify.addr & (PAGE_SIZE - 1))
930 return -EINVAL;
931 if (vma->vm_end - vma->vm_start != notify.size)
932 return -ENOTSUPP;
933
934 vma->vm_ops = &vhost_vdpa_vm_ops;
935 return 0;
936}
937#endif
938
939static const struct file_operations vhost_vdpa_fops = {
940 .owner = THIS_MODULE,
941 .open = vhost_vdpa_open,
942 .release = vhost_vdpa_release,
943 .write_iter = vhost_vdpa_chr_write_iter,
944 .unlocked_ioctl = vhost_vdpa_unlocked_ioctl,
945#ifdef CONFIG_MMU
946 .mmap = vhost_vdpa_mmap,
947#endif
948 .compat_ioctl = compat_ptr_ioctl,
949};
950
951static void vhost_vdpa_release_dev(struct device *device)
952{
953 struct vhost_vdpa *v =
954 container_of(device, struct vhost_vdpa, dev);
955
956 ida_simple_remove(&vhost_vdpa_ida, v->minor);
957 kfree(v->vqs);
958 kfree(v);
959}
960
961static int vhost_vdpa_probe(struct vdpa_device *vdpa)
962{
963 const struct vdpa_config_ops *ops = vdpa->config;
964 struct vhost_vdpa *v;
965 int minor;
966 int r;
967
968
969 if (ops->get_device_id(vdpa) != VIRTIO_ID_NET)
970 return -ENOTSUPP;
971
972 v = kzalloc(sizeof(*v), GFP_KERNEL | __GFP_RETRY_MAYFAIL);
973 if (!v)
974 return -ENOMEM;
975
976 minor = ida_simple_get(&vhost_vdpa_ida, 0,
977 VHOST_VDPA_DEV_MAX, GFP_KERNEL);
978 if (minor < 0) {
979 kfree(v);
980 return minor;
981 }
982
983 atomic_set(&v->opened, 0);
984 v->minor = minor;
985 v->vdpa = vdpa;
986 v->nvqs = vdpa->nvqs;
987 v->virtio_id = ops->get_device_id(vdpa);
988
989 device_initialize(&v->dev);
990 v->dev.release = vhost_vdpa_release_dev;
991 v->dev.parent = &vdpa->dev;
992 v->dev.devt = MKDEV(MAJOR(vhost_vdpa_major), minor);
993 v->vqs = kmalloc_array(v->nvqs, sizeof(struct vhost_virtqueue),
994 GFP_KERNEL);
995 if (!v->vqs) {
996 r = -ENOMEM;
997 goto err;
998 }
999
1000 r = dev_set_name(&v->dev, "vhost-vdpa-%u", minor);
1001 if (r)
1002 goto err;
1003
1004 cdev_init(&v->cdev, &vhost_vdpa_fops);
1005 v->cdev.owner = THIS_MODULE;
1006
1007 r = cdev_device_add(&v->cdev, &v->dev);
1008 if (r)
1009 goto err;
1010
1011 init_completion(&v->completion);
1012 vdpa_set_drvdata(vdpa, v);
1013
1014 return 0;
1015
1016err:
1017 put_device(&v->dev);
1018 return r;
1019}
1020
1021static void vhost_vdpa_remove(struct vdpa_device *vdpa)
1022{
1023 struct vhost_vdpa *v = vdpa_get_drvdata(vdpa);
1024 int opened;
1025
1026 cdev_device_del(&v->cdev, &v->dev);
1027
1028 do {
1029 opened = atomic_cmpxchg(&v->opened, 0, 1);
1030 if (!opened)
1031 break;
1032 wait_for_completion(&v->completion);
1033 } while (1);
1034
1035 put_device(&v->dev);
1036}
1037
1038static struct vdpa_driver vhost_vdpa_driver = {
1039 .driver = {
1040 .name = "vhost_vdpa",
1041 },
1042 .probe = vhost_vdpa_probe,
1043 .remove = vhost_vdpa_remove,
1044};
1045
1046static int __init vhost_vdpa_init(void)
1047{
1048 int r;
1049
1050 r = alloc_chrdev_region(&vhost_vdpa_major, 0, VHOST_VDPA_DEV_MAX,
1051 "vhost-vdpa");
1052 if (r)
1053 goto err_alloc_chrdev;
1054
1055 r = vdpa_register_driver(&vhost_vdpa_driver);
1056 if (r)
1057 goto err_vdpa_register_driver;
1058
1059 return 0;
1060
1061err_vdpa_register_driver:
1062 unregister_chrdev_region(vhost_vdpa_major, VHOST_VDPA_DEV_MAX);
1063err_alloc_chrdev:
1064 return r;
1065}
1066module_init(vhost_vdpa_init);
1067
1068static void __exit vhost_vdpa_exit(void)
1069{
1070 vdpa_unregister_driver(&vhost_vdpa_driver);
1071 unregister_chrdev_region(vhost_vdpa_major, VHOST_VDPA_DEV_MAX);
1072}
1073module_exit(vhost_vdpa_exit);
1074
1075MODULE_VERSION("0.0.1");
1076MODULE_LICENSE("GPL v2");
1077MODULE_AUTHOR("Intel Corporation");
1078MODULE_DESCRIPTION("vDPA-based vhost backend for virtio");
1079
