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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2018-2020 Intel Corporation.
4 * Copyright (C) 2020 Red Hat, Inc.
5 *
6 * Author: Tiwei Bie <tiwei.bie@intel.com>
7 * Jason Wang <jasowang@redhat.com>
8 *
9 * Thanks Michael S. Tsirkin for the valuable comments and
10 * suggestions. And thanks to Cunming Liang and Zhihong Wang for all
11 * their supports.
12 */
13
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/slab.h>
20#include <linux/iommu.h>
21#include <linux/uuid.h>
22#include <linux/vdpa.h>
23#include <linux/nospec.h>
24#include <linux/vhost.h>
25
26#include "vhost.h"
27
28enum {
29 VHOST_VDPA_BACKEND_FEATURES =
30 (1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2) |
31 (1ULL << VHOST_BACKEND_F_IOTLB_BATCH),
32};
33
34#define VHOST_VDPA_DEV_MAX (1U << MINORBITS)
35
36struct vhost_vdpa {
37 struct vhost_dev vdev;
38 struct iommu_domain *domain;
39 struct vhost_virtqueue *vqs;
40 struct completion completion;
41 struct vdpa_device *vdpa;
42 struct device dev;
43 struct cdev cdev;
44 atomic_t opened;
45 int nvqs;
46 int virtio_id;
47 int minor;
48 struct eventfd_ctx *config_ctx;
49 int in_batch;
50 struct vdpa_iova_range range;
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 irq_bypass_unregister_producer(&vq->call_ctx.producer);
101 if (!vq->call_ctx.ctx || irq < 0)
102 return;
103
104 vq->call_ctx.producer.token = vq->call_ctx.ctx;
105 vq->call_ctx.producer.irq = irq;
106 ret = irq_bypass_register_producer(&vq->call_ctx.producer);
107 if (unlikely(ret))
108 dev_info(&v->dev, "vq %u, irq bypass producer (token %p) registration fails, ret = %d\n",
109 qid, vq->call_ctx.producer.token, ret);
110}
111
112static void vhost_vdpa_unsetup_vq_irq(struct vhost_vdpa *v, u16 qid)
113{
114 struct vhost_virtqueue *vq = &v->vqs[qid];
115
116 irq_bypass_unregister_producer(&vq->call_ctx.producer);
117}
118
119static void vhost_vdpa_reset(struct vhost_vdpa *v)
120{
121 struct vdpa_device *vdpa = v->vdpa;
122
123 vdpa_reset(vdpa);
124 v->in_batch = 0;
125}
126
127static long vhost_vdpa_get_device_id(struct vhost_vdpa *v, u8 __user *argp)
128{
129 struct vdpa_device *vdpa = v->vdpa;
130 const struct vdpa_config_ops *ops = vdpa->config;
131 u32 device_id;
132
133 device_id = ops->get_device_id(vdpa);
134
135 if (copy_to_user(argp, &device_id, sizeof(device_id)))
136 return -EFAULT;
137
138 return 0;
139}
140
141static long vhost_vdpa_get_status(struct vhost_vdpa *v, u8 __user *statusp)
142{
143 struct vdpa_device *vdpa = v->vdpa;
144 const struct vdpa_config_ops *ops = vdpa->config;
145 u8 status;
146
147 status = ops->get_status(vdpa);
148
149 if (copy_to_user(statusp, &status, sizeof(status)))
150 return -EFAULT;
151
152 return 0;
153}
154
155static long vhost_vdpa_set_status(struct vhost_vdpa *v, u8 __user *statusp)
156{
157 struct vdpa_device *vdpa = v->vdpa;
158 const struct vdpa_config_ops *ops = vdpa->config;
159 u8 status, status_old;
160 int nvqs = v->nvqs;
161 u16 i;
162
163 if (copy_from_user(&status, statusp, sizeof(status)))
164 return -EFAULT;
165
166 status_old = ops->get_status(vdpa);
167
168 /*
169 * Userspace shouldn't remove status bits unless reset the
170 * status to 0.
171 */
172 if (status != 0 && (ops->get_status(vdpa) & ~status) != 0)
173 return -EINVAL;
174
175 ops->set_status(vdpa, status);
176
177 if ((status & VIRTIO_CONFIG_S_DRIVER_OK) && !(status_old & VIRTIO_CONFIG_S_DRIVER_OK))
178 for (i = 0; i < nvqs; i++)
179 vhost_vdpa_setup_vq_irq(v, i);
180
181 if ((status_old & VIRTIO_CONFIG_S_DRIVER_OK) && !(status & VIRTIO_CONFIG_S_DRIVER_OK))
182 for (i = 0; i < nvqs; i++)
183 vhost_vdpa_unsetup_vq_irq(v, i);
184
185 return 0;
186}
187
188static int vhost_vdpa_config_validate(struct vhost_vdpa *v,
189 struct vhost_vdpa_config *c)
190{
191 struct vdpa_device *vdpa = v->vdpa;
192 long size = vdpa->config->get_config_size(vdpa);
193
194 if (c->len == 0)
195 return -EINVAL;
196
197 if (c->len > size - c->off)
198 return -E2BIG;
199
200 return 0;
201}
202
203static long vhost_vdpa_get_config(struct vhost_vdpa *v,
204 struct vhost_vdpa_config __user *c)
205{
206 struct vdpa_device *vdpa = v->vdpa;
207 struct vhost_vdpa_config config;
208 unsigned long size = offsetof(struct vhost_vdpa_config, buf);
209 u8 *buf;
210
211 if (copy_from_user(&config, c, size))
212 return -EFAULT;
213 if (vhost_vdpa_config_validate(v, &config))
214 return -EINVAL;
215 buf = kvzalloc(config.len, GFP_KERNEL);
216 if (!buf)
217 return -ENOMEM;
218
219 vdpa_get_config(vdpa, config.off, buf, config.len);
220
221 if (copy_to_user(c->buf, buf, config.len)) {
222 kvfree(buf);
223 return -EFAULT;
224 }
225
226 kvfree(buf);
227 return 0;
228}
229
230static long vhost_vdpa_set_config(struct vhost_vdpa *v,
231 struct vhost_vdpa_config __user *c)
232{
233 struct vdpa_device *vdpa = v->vdpa;
234 const struct vdpa_config_ops *ops = vdpa->config;
235 struct vhost_vdpa_config config;
236 unsigned long size = offsetof(struct vhost_vdpa_config, buf);
237 u8 *buf;
238
239 if (copy_from_user(&config, c, size))
240 return -EFAULT;
241 if (vhost_vdpa_config_validate(v, &config))
242 return -EINVAL;
243
244 buf = vmemdup_user(c->buf, config.len);
245 if (IS_ERR(buf))
246 return PTR_ERR(buf);
247
248 ops->set_config(vdpa, config.off, buf, config.len);
249
250 kvfree(buf);
251 return 0;
252}
253
254static long vhost_vdpa_get_features(struct vhost_vdpa *v, u64 __user *featurep)
255{
256 struct vdpa_device *vdpa = v->vdpa;
257 const struct vdpa_config_ops *ops = vdpa->config;
258 u64 features;
259
260 features = ops->get_features(vdpa);
261
262 if (copy_to_user(featurep, &features, sizeof(features)))
263 return -EFAULT;
264
265 return 0;
266}
267
268static long vhost_vdpa_set_features(struct vhost_vdpa *v, u64 __user *featurep)
269{
270 struct vdpa_device *vdpa = v->vdpa;
271 const struct vdpa_config_ops *ops = vdpa->config;
272 u64 features;
273
274 /*
275 * It's not allowed to change the features after they have
276 * been negotiated.
277 */
278 if (ops->get_status(vdpa) & VIRTIO_CONFIG_S_FEATURES_OK)
279 return -EBUSY;
280
281 if (copy_from_user(&features, featurep, sizeof(features)))
282 return -EFAULT;
283
284 if (vdpa_set_features(vdpa, features))
285 return -EINVAL;
286
287 return 0;
288}
289
290static long vhost_vdpa_get_vring_num(struct vhost_vdpa *v, u16 __user *argp)
291{
292 struct vdpa_device *vdpa = v->vdpa;
293 const struct vdpa_config_ops *ops = vdpa->config;
294 u16 num;
295
296 num = ops->get_vq_num_max(vdpa);
297
298 if (copy_to_user(argp, &num, sizeof(num)))
299 return -EFAULT;
300
301 return 0;
302}
303
304static void vhost_vdpa_config_put(struct vhost_vdpa *v)
305{
306 if (v->config_ctx) {
307 eventfd_ctx_put(v->config_ctx);
308 v->config_ctx = NULL;
309 }
310}
311
312static long vhost_vdpa_set_config_call(struct vhost_vdpa *v, u32 __user *argp)
313{
314 struct vdpa_callback cb;
315 int fd;
316 struct eventfd_ctx *ctx;
317
318 cb.callback = vhost_vdpa_config_cb;
319 cb.private = v;
320 if (copy_from_user(&fd, argp, sizeof(fd)))
321 return -EFAULT;
322
323 ctx = fd == VHOST_FILE_UNBIND ? NULL : eventfd_ctx_fdget(fd);
324 swap(ctx, v->config_ctx);
325
326 if (!IS_ERR_OR_NULL(ctx))
327 eventfd_ctx_put(ctx);
328
329 if (IS_ERR(v->config_ctx)) {
330 long ret = PTR_ERR(v->config_ctx);
331
332 v->config_ctx = NULL;
333 return ret;
334 }
335
336 v->vdpa->config->set_config_cb(v->vdpa, &cb);
337
338 return 0;
339}
340
341static long vhost_vdpa_get_iova_range(struct vhost_vdpa *v, u32 __user *argp)
342{
343 struct vhost_vdpa_iova_range range = {
344 .first = v->range.first,
345 .last = v->range.last,
346 };
347
348 if (copy_to_user(argp, &range, sizeof(range)))
349 return -EFAULT;
350 return 0;
351}
352
353static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
354 void __user *argp)
355{
356 struct vdpa_device *vdpa = v->vdpa;
357 const struct vdpa_config_ops *ops = vdpa->config;
358 struct vdpa_vq_state vq_state;
359 struct vdpa_callback cb;
360 struct vhost_virtqueue *vq;
361 struct vhost_vring_state s;
362 u32 idx;
363 long r;
364
365 r = get_user(idx, (u32 __user *)argp);
366 if (r < 0)
367 return r;
368
369 if (idx >= v->nvqs)
370 return -ENOBUFS;
371
372 idx = array_index_nospec(idx, v->nvqs);
373 vq = &v->vqs[idx];
374
375 switch (cmd) {
376 case VHOST_VDPA_SET_VRING_ENABLE:
377 if (copy_from_user(&s, argp, sizeof(s)))
378 return -EFAULT;
379 ops->set_vq_ready(vdpa, idx, s.num);
380 return 0;
381 case VHOST_GET_VRING_BASE:
382 r = ops->get_vq_state(v->vdpa, idx, &vq_state);
383 if (r)
384 return r;
385
386 vq->last_avail_idx = vq_state.split.avail_index;
387 break;
388 }
389
390 r = vhost_vring_ioctl(&v->vdev, cmd, argp);
391 if (r)
392 return r;
393
394 switch (cmd) {
395 case VHOST_SET_VRING_ADDR:
396 if (ops->set_vq_address(vdpa, idx,
397 (u64)(uintptr_t)vq->desc,
398 (u64)(uintptr_t)vq->avail,
399 (u64)(uintptr_t)vq->used))
400 r = -EINVAL;
401 break;
402
403 case VHOST_SET_VRING_BASE:
404 vq_state.split.avail_index = vq->last_avail_idx;
405 if (ops->set_vq_state(vdpa, idx, &vq_state))
406 r = -EINVAL;
407 break;
408
409 case VHOST_SET_VRING_CALL:
410 if (vq->call_ctx.ctx) {
411 cb.callback = vhost_vdpa_virtqueue_cb;
412 cb.private = vq;
413 } else {
414 cb.callback = NULL;
415 cb.private = NULL;
416 }
417 ops->set_vq_cb(vdpa, idx, &cb);
418 vhost_vdpa_setup_vq_irq(v, idx);
419 break;
420
421 case VHOST_SET_VRING_NUM:
422 ops->set_vq_num(vdpa, idx, vq->num);
423 break;
424 }
425
426 return r;
427}
428
429static long vhost_vdpa_unlocked_ioctl(struct file *filep,
430 unsigned int cmd, unsigned long arg)
431{
432 struct vhost_vdpa *v = filep->private_data;
433 struct vhost_dev *d = &v->vdev;
434 void __user *argp = (void __user *)arg;
435 u64 __user *featurep = argp;
436 u64 features;
437 long r = 0;
438
439 if (cmd == VHOST_SET_BACKEND_FEATURES) {
440 if (copy_from_user(&features, featurep, sizeof(features)))
441 return -EFAULT;
442 if (features & ~VHOST_VDPA_BACKEND_FEATURES)
443 return -EOPNOTSUPP;
444 vhost_set_backend_features(&v->vdev, features);
445 return 0;
446 }
447
448 mutex_lock(&d->mutex);
449
450 switch (cmd) {
451 case VHOST_VDPA_GET_DEVICE_ID:
452 r = vhost_vdpa_get_device_id(v, argp);
453 break;
454 case VHOST_VDPA_GET_STATUS:
455 r = vhost_vdpa_get_status(v, argp);
456 break;
457 case VHOST_VDPA_SET_STATUS:
458 r = vhost_vdpa_set_status(v, argp);
459 break;
460 case VHOST_VDPA_GET_CONFIG:
461 r = vhost_vdpa_get_config(v, argp);
462 break;
463 case VHOST_VDPA_SET_CONFIG:
464 r = vhost_vdpa_set_config(v, argp);
465 break;
466 case VHOST_GET_FEATURES:
467 r = vhost_vdpa_get_features(v, argp);
468 break;
469 case VHOST_SET_FEATURES:
470 r = vhost_vdpa_set_features(v, argp);
471 break;
472 case VHOST_VDPA_GET_VRING_NUM:
473 r = vhost_vdpa_get_vring_num(v, argp);
474 break;
475 case VHOST_SET_LOG_BASE:
476 case VHOST_SET_LOG_FD:
477 r = -ENOIOCTLCMD;
478 break;
479 case VHOST_VDPA_SET_CONFIG_CALL:
480 r = vhost_vdpa_set_config_call(v, argp);
481 break;
482 case VHOST_GET_BACKEND_FEATURES:
483 features = VHOST_VDPA_BACKEND_FEATURES;
484 if (copy_to_user(featurep, &features, sizeof(features)))
485 r = -EFAULT;
486 break;
487 case VHOST_VDPA_GET_IOVA_RANGE:
488 r = vhost_vdpa_get_iova_range(v, argp);
489 break;
490 default:
491 r = vhost_dev_ioctl(&v->vdev, cmd, argp);
492 if (r == -ENOIOCTLCMD)
493 r = vhost_vdpa_vring_ioctl(v, cmd, argp);
494 break;
495 }
496
497 mutex_unlock(&d->mutex);
498 return r;
499}
500
501static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last)
502{
503 struct vhost_dev *dev = &v->vdev;
504 struct vhost_iotlb *iotlb = dev->iotlb;
505 struct vhost_iotlb_map *map;
506 struct page *page;
507 unsigned long pfn, pinned;
508
509 while ((map = vhost_iotlb_itree_first(iotlb, start, last)) != NULL) {
510 pinned = map->size >> PAGE_SHIFT;
511 for (pfn = map->addr >> PAGE_SHIFT;
512 pinned > 0; pfn++, pinned--) {
513 page = pfn_to_page(pfn);
514 if (map->perm & VHOST_ACCESS_WO)
515 set_page_dirty_lock(page);
516 unpin_user_page(page);
517 }
518 atomic64_sub(map->size >> PAGE_SHIFT, &dev->mm->pinned_vm);
519 vhost_iotlb_map_free(iotlb, map);
520 }
521}
522
523static void vhost_vdpa_iotlb_free(struct vhost_vdpa *v)
524{
525 struct vhost_dev *dev = &v->vdev;
526
527 vhost_vdpa_iotlb_unmap(v, 0ULL, 0ULL - 1);
528 kfree(dev->iotlb);
529 dev->iotlb = NULL;
530}
531
532static int perm_to_iommu_flags(u32 perm)
533{
534 int flags = 0;
535
536 switch (perm) {
537 case VHOST_ACCESS_WO:
538 flags |= IOMMU_WRITE;
539 break;
540 case VHOST_ACCESS_RO:
541 flags |= IOMMU_READ;
542 break;
543 case VHOST_ACCESS_RW:
544 flags |= (IOMMU_WRITE | IOMMU_READ);
545 break;
546 default:
547 WARN(1, "invalidate vhost IOTLB permission\n");
548 break;
549 }
550
551 return flags | IOMMU_CACHE;
552}
553
554static int vhost_vdpa_map(struct vhost_vdpa *v,
555 u64 iova, u64 size, u64 pa, u32 perm)
556{
557 struct vhost_dev *dev = &v->vdev;
558 struct vdpa_device *vdpa = v->vdpa;
559 const struct vdpa_config_ops *ops = vdpa->config;
560 int r = 0;
561
562 r = vhost_iotlb_add_range(dev->iotlb, iova, iova + size - 1,
563 pa, perm);
564 if (r)
565 return r;
566
567 if (ops->dma_map) {
568 r = ops->dma_map(vdpa, iova, size, pa, perm);
569 } else if (ops->set_map) {
570 if (!v->in_batch)
571 r = ops->set_map(vdpa, dev->iotlb);
572 } else {
573 r = iommu_map(v->domain, iova, pa, size,
574 perm_to_iommu_flags(perm));
575 }
576
577 if (r)
578 vhost_iotlb_del_range(dev->iotlb, iova, iova + size - 1);
579 else
580 atomic64_add(size >> PAGE_SHIFT, &dev->mm->pinned_vm);
581
582 return r;
583}
584
585static void vhost_vdpa_unmap(struct vhost_vdpa *v, u64 iova, u64 size)
586{
587 struct vhost_dev *dev = &v->vdev;
588 struct vdpa_device *vdpa = v->vdpa;
589 const struct vdpa_config_ops *ops = vdpa->config;
590
591 vhost_vdpa_iotlb_unmap(v, iova, iova + size - 1);
592
593 if (ops->dma_map) {
594 ops->dma_unmap(vdpa, iova, size);
595 } else if (ops->set_map) {
596 if (!v->in_batch)
597 ops->set_map(vdpa, dev->iotlb);
598 } else {
599 iommu_unmap(v->domain, iova, size);
600 }
601}
602
603static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
604 struct vhost_iotlb_msg *msg)
605{
606 struct vhost_dev *dev = &v->vdev;
607 struct vhost_iotlb *iotlb = dev->iotlb;
608 struct page **page_list;
609 unsigned long list_size = PAGE_SIZE / sizeof(struct page *);
610 unsigned int gup_flags = FOLL_LONGTERM;
611 unsigned long npages, cur_base, map_pfn, last_pfn = 0;
612 unsigned long lock_limit, sz2pin, nchunks, i;
613 u64 iova = msg->iova;
614 long pinned;
615 int ret = 0;
616
617 if (msg->iova < v->range.first || !msg->size ||
618 msg->iova > U64_MAX - msg->size + 1 ||
619 msg->iova + msg->size - 1 > v->range.last)
620 return -EINVAL;
621
622 if (vhost_iotlb_itree_first(iotlb, msg->iova,
623 msg->iova + msg->size - 1))
624 return -EEXIST;
625
626 /* Limit the use of memory for bookkeeping */
627 page_list = (struct page **) __get_free_page(GFP_KERNEL);
628 if (!page_list)
629 return -ENOMEM;
630
631 if (msg->perm & VHOST_ACCESS_WO)
632 gup_flags |= FOLL_WRITE;
633
634 npages = PAGE_ALIGN(msg->size + (iova & ~PAGE_MASK)) >> PAGE_SHIFT;
635 if (!npages) {
636 ret = -EINVAL;
637 goto free;
638 }
639
640 mmap_read_lock(dev->mm);
641
642 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
643 if (npages + atomic64_read(&dev->mm->pinned_vm) > lock_limit) {
644 ret = -ENOMEM;
645 goto unlock;
646 }
647
648 cur_base = msg->uaddr & PAGE_MASK;
649 iova &= PAGE_MASK;
650 nchunks = 0;
651
652 while (npages) {
653 sz2pin = min_t(unsigned long, npages, list_size);
654 pinned = pin_user_pages(cur_base, sz2pin,
655 gup_flags, page_list, NULL);
656 if (sz2pin != pinned) {
657 if (pinned < 0) {
658 ret = pinned;
659 } else {
660 unpin_user_pages(page_list, pinned);
661 ret = -ENOMEM;
662 }
663 goto out;
664 }
665 nchunks++;
666
667 if (!last_pfn)
668 map_pfn = page_to_pfn(page_list[0]);
669
670 for (i = 0; i < pinned; i++) {
671 unsigned long this_pfn = page_to_pfn(page_list[i]);
672 u64 csize;
673
674 if (last_pfn && (this_pfn != last_pfn + 1)) {
675 /* Pin a contiguous chunk of memory */
676 csize = (last_pfn - map_pfn + 1) << PAGE_SHIFT;
677 ret = vhost_vdpa_map(v, iova, csize,
678 map_pfn << PAGE_SHIFT,
679 msg->perm);
680 if (ret) {
681 /*
682 * Unpin the pages that are left unmapped
683 * from this point on in the current
684 * page_list. The remaining outstanding
685 * ones which may stride across several
686 * chunks will be covered in the common
687 * error path subsequently.
688 */
689 unpin_user_pages(&page_list[i],
690 pinned - i);
691 goto out;
692 }
693
694 map_pfn = this_pfn;
695 iova += csize;
696 nchunks = 0;
697 }
698
699 last_pfn = this_pfn;
700 }
701
702 cur_base += pinned << PAGE_SHIFT;
703 npages -= pinned;
704 }
705
706 /* Pin the rest chunk */
707 ret = vhost_vdpa_map(v, iova, (last_pfn - map_pfn + 1) << PAGE_SHIFT,
708 map_pfn << PAGE_SHIFT, msg->perm);
709out:
710 if (ret) {
711 if (nchunks) {
712 unsigned long pfn;
713
714 /*
715 * Unpin the outstanding pages which are yet to be
716 * mapped but haven't due to vdpa_map() or
717 * pin_user_pages() failure.
718 *
719 * Mapped pages are accounted in vdpa_map(), hence
720 * the corresponding unpinning will be handled by
721 * vdpa_unmap().
722 */
723 WARN_ON(!last_pfn);
724 for (pfn = map_pfn; pfn <= last_pfn; pfn++)
725 unpin_user_page(pfn_to_page(pfn));
726 }
727 vhost_vdpa_unmap(v, msg->iova, msg->size);
728 }
729unlock:
730 mmap_read_unlock(dev->mm);
731free:
732 free_page((unsigned long)page_list);
733 return ret;
734}
735
736static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev,
737 struct vhost_iotlb_msg *msg)
738{
739 struct vhost_vdpa *v = container_of(dev, struct vhost_vdpa, vdev);
740 struct vdpa_device *vdpa = v->vdpa;
741 const struct vdpa_config_ops *ops = vdpa->config;
742 int r = 0;
743
744 mutex_lock(&dev->mutex);
745
746 r = vhost_dev_check_owner(dev);
747 if (r)
748 goto unlock;
749
750 switch (msg->type) {
751 case VHOST_IOTLB_UPDATE:
752 r = vhost_vdpa_process_iotlb_update(v, msg);
753 break;
754 case VHOST_IOTLB_INVALIDATE:
755 vhost_vdpa_unmap(v, msg->iova, msg->size);
756 break;
757 case VHOST_IOTLB_BATCH_BEGIN:
758 v->in_batch = true;
759 break;
760 case VHOST_IOTLB_BATCH_END:
761 if (v->in_batch && ops->set_map)
762 ops->set_map(vdpa, dev->iotlb);
763 v->in_batch = false;
764 break;
765 default:
766 r = -EINVAL;
767 break;
768 }
769unlock:
770 mutex_unlock(&dev->mutex);
771
772 return r;
773}
774
775static ssize_t vhost_vdpa_chr_write_iter(struct kiocb *iocb,
776 struct iov_iter *from)
777{
778 struct file *file = iocb->ki_filp;
779 struct vhost_vdpa *v = file->private_data;
780 struct vhost_dev *dev = &v->vdev;
781
782 return vhost_chr_write_iter(dev, from);
783}
784
785static int vhost_vdpa_alloc_domain(struct vhost_vdpa *v)
786{
787 struct vdpa_device *vdpa = v->vdpa;
788 const struct vdpa_config_ops *ops = vdpa->config;
789 struct device *dma_dev = vdpa_get_dma_dev(vdpa);
790 struct bus_type *bus;
791 int ret;
792
793 /* Device want to do DMA by itself */
794 if (ops->set_map || ops->dma_map)
795 return 0;
796
797 bus = dma_dev->bus;
798 if (!bus)
799 return -EFAULT;
800
801 if (!iommu_capable(bus, IOMMU_CAP_CACHE_COHERENCY))
802 return -ENOTSUPP;
803
804 v->domain = iommu_domain_alloc(bus);
805 if (!v->domain)
806 return -EIO;
807
808 ret = iommu_attach_device(v->domain, dma_dev);
809 if (ret)
810 goto err_attach;
811
812 return 0;
813
814err_attach:
815 iommu_domain_free(v->domain);
816 return ret;
817}
818
819static void vhost_vdpa_free_domain(struct vhost_vdpa *v)
820{
821 struct vdpa_device *vdpa = v->vdpa;
822 struct device *dma_dev = vdpa_get_dma_dev(vdpa);
823
824 if (v->domain) {
825 iommu_detach_device(v->domain, dma_dev);
826 iommu_domain_free(v->domain);
827 }
828
829 v->domain = NULL;
830}
831
832static void vhost_vdpa_set_iova_range(struct vhost_vdpa *v)
833{
834 struct vdpa_iova_range *range = &v->range;
835 struct vdpa_device *vdpa = v->vdpa;
836 const struct vdpa_config_ops *ops = vdpa->config;
837
838 if (ops->get_iova_range) {
839 *range = ops->get_iova_range(vdpa);
840 } else if (v->domain && v->domain->geometry.force_aperture) {
841 range->first = v->domain->geometry.aperture_start;
842 range->last = v->domain->geometry.aperture_end;
843 } else {
844 range->first = 0;
845 range->last = ULLONG_MAX;
846 }
847}
848
849static int vhost_vdpa_open(struct inode *inode, struct file *filep)
850{
851 struct vhost_vdpa *v;
852 struct vhost_dev *dev;
853 struct vhost_virtqueue **vqs;
854 int nvqs, i, r, opened;
855
856 v = container_of(inode->i_cdev, struct vhost_vdpa, cdev);
857
858 opened = atomic_cmpxchg(&v->opened, 0, 1);
859 if (opened)
860 return -EBUSY;
861
862 nvqs = v->nvqs;
863 vhost_vdpa_reset(v);
864
865 vqs = kmalloc_array(nvqs, sizeof(*vqs), GFP_KERNEL);
866 if (!vqs) {
867 r = -ENOMEM;
868 goto err;
869 }
870
871 dev = &v->vdev;
872 for (i = 0; i < nvqs; i++) {
873 vqs[i] = &v->vqs[i];
874 vqs[i]->handle_kick = handle_vq_kick;
875 }
876 vhost_dev_init(dev, vqs, nvqs, 0, 0, 0, false,
877 vhost_vdpa_process_iotlb_msg);
878
879 dev->iotlb = vhost_iotlb_alloc(0, 0);
880 if (!dev->iotlb) {
881 r = -ENOMEM;
882 goto err_init_iotlb;
883 }
884
885 r = vhost_vdpa_alloc_domain(v);
886 if (r)
887 goto err_init_iotlb;
888
889 vhost_vdpa_set_iova_range(v);
890
891 filep->private_data = v;
892
893 return 0;
894
895err_init_iotlb:
896 vhost_dev_cleanup(&v->vdev);
897 kfree(vqs);
898err:
899 atomic_dec(&v->opened);
900 return r;
901}
902
903static void vhost_vdpa_clean_irq(struct vhost_vdpa *v)
904{
905 int i;
906
907 for (i = 0; i < v->nvqs; i++)
908 vhost_vdpa_unsetup_vq_irq(v, i);
909}
910
911static int vhost_vdpa_release(struct inode *inode, struct file *filep)
912{
913 struct vhost_vdpa *v = filep->private_data;
914 struct vhost_dev *d = &v->vdev;
915
916 mutex_lock(&d->mutex);
917 filep->private_data = NULL;
918 vhost_vdpa_reset(v);
919 vhost_dev_stop(&v->vdev);
920 vhost_vdpa_iotlb_free(v);
921 vhost_vdpa_free_domain(v);
922 vhost_vdpa_config_put(v);
923 vhost_vdpa_clean_irq(v);
924 vhost_dev_cleanup(&v->vdev);
925 kfree(v->vdev.vqs);
926 mutex_unlock(&d->mutex);
927
928 atomic_dec(&v->opened);
929 complete(&v->completion);
930
931 return 0;
932}
933
934#ifdef CONFIG_MMU
935static vm_fault_t vhost_vdpa_fault(struct vm_fault *vmf)
936{
937 struct vhost_vdpa *v = vmf->vma->vm_file->private_data;
938 struct vdpa_device *vdpa = v->vdpa;
939 const struct vdpa_config_ops *ops = vdpa->config;
940 struct vdpa_notification_area notify;
941 struct vm_area_struct *vma = vmf->vma;
942 u16 index = vma->vm_pgoff;
943
944 notify = ops->get_vq_notification(vdpa, index);
945
946 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
947 if (remap_pfn_range(vma, vmf->address & PAGE_MASK,
948 notify.addr >> PAGE_SHIFT, PAGE_SIZE,
949 vma->vm_page_prot))
950 return VM_FAULT_SIGBUS;
951
952 return VM_FAULT_NOPAGE;
953}
954
955static const struct vm_operations_struct vhost_vdpa_vm_ops = {
956 .fault = vhost_vdpa_fault,
957};
958
959static int vhost_vdpa_mmap(struct file *file, struct vm_area_struct *vma)
960{
961 struct vhost_vdpa *v = vma->vm_file->private_data;
962 struct vdpa_device *vdpa = v->vdpa;
963 const struct vdpa_config_ops *ops = vdpa->config;
964 struct vdpa_notification_area notify;
965 unsigned long index = vma->vm_pgoff;
966
967 if (vma->vm_end - vma->vm_start != PAGE_SIZE)
968 return -EINVAL;
969 if ((vma->vm_flags & VM_SHARED) == 0)
970 return -EINVAL;
971 if (vma->vm_flags & VM_READ)
972 return -EINVAL;
973 if (index > 65535)
974 return -EINVAL;
975 if (!ops->get_vq_notification)
976 return -ENOTSUPP;
977
978 /* To be safe and easily modelled by userspace, We only
979 * support the doorbell which sits on the page boundary and
980 * does not share the page with other registers.
981 */
982 notify = ops->get_vq_notification(vdpa, index);
983 if (notify.addr & (PAGE_SIZE - 1))
984 return -EINVAL;
985 if (vma->vm_end - vma->vm_start != notify.size)
986 return -ENOTSUPP;
987
988 vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
989 vma->vm_ops = &vhost_vdpa_vm_ops;
990 return 0;
991}
992#endif /* CONFIG_MMU */
993
994static const struct file_operations vhost_vdpa_fops = {
995 .owner = THIS_MODULE,
996 .open = vhost_vdpa_open,
997 .release = vhost_vdpa_release,
998 .write_iter = vhost_vdpa_chr_write_iter,
999 .unlocked_ioctl = vhost_vdpa_unlocked_ioctl,
1000#ifdef CONFIG_MMU
1001 .mmap = vhost_vdpa_mmap,
1002#endif /* CONFIG_MMU */
1003 .compat_ioctl = compat_ptr_ioctl,
1004};
1005
1006static void vhost_vdpa_release_dev(struct device *device)
1007{
1008 struct vhost_vdpa *v =
1009 container_of(device, struct vhost_vdpa, dev);
1010
1011 ida_simple_remove(&vhost_vdpa_ida, v->minor);
1012 kfree(v->vqs);
1013 kfree(v);
1014}
1015
1016static int vhost_vdpa_probe(struct vdpa_device *vdpa)
1017{
1018 const struct vdpa_config_ops *ops = vdpa->config;
1019 struct vhost_vdpa *v;
1020 int minor;
1021 int r;
1022
1023 v = kzalloc(sizeof(*v), GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1024 if (!v)
1025 return -ENOMEM;
1026
1027 minor = ida_simple_get(&vhost_vdpa_ida, 0,
1028 VHOST_VDPA_DEV_MAX, GFP_KERNEL);
1029 if (minor < 0) {
1030 kfree(v);
1031 return minor;
1032 }
1033
1034 atomic_set(&v->opened, 0);
1035 v->minor = minor;
1036 v->vdpa = vdpa;
1037 v->nvqs = vdpa->nvqs;
1038 v->virtio_id = ops->get_device_id(vdpa);
1039
1040 device_initialize(&v->dev);
1041 v->dev.release = vhost_vdpa_release_dev;
1042 v->dev.parent = &vdpa->dev;
1043 v->dev.devt = MKDEV(MAJOR(vhost_vdpa_major), minor);
1044 v->vqs = kmalloc_array(v->nvqs, sizeof(struct vhost_virtqueue),
1045 GFP_KERNEL);
1046 if (!v->vqs) {
1047 r = -ENOMEM;
1048 goto err;
1049 }
1050
1051 r = dev_set_name(&v->dev, "vhost-vdpa-%u", minor);
1052 if (r)
1053 goto err;
1054
1055 cdev_init(&v->cdev, &vhost_vdpa_fops);
1056 v->cdev.owner = THIS_MODULE;
1057
1058 r = cdev_device_add(&v->cdev, &v->dev);
1059 if (r)
1060 goto err;
1061
1062 init_completion(&v->completion);
1063 vdpa_set_drvdata(vdpa, v);
1064
1065 return 0;
1066
1067err:
1068 put_device(&v->dev);
1069 return r;
1070}
1071
1072static void vhost_vdpa_remove(struct vdpa_device *vdpa)
1073{
1074 struct vhost_vdpa *v = vdpa_get_drvdata(vdpa);
1075 int opened;
1076
1077 cdev_device_del(&v->cdev, &v->dev);
1078
1079 do {
1080 opened = atomic_cmpxchg(&v->opened, 0, 1);
1081 if (!opened)
1082 break;
1083 wait_for_completion(&v->completion);
1084 } while (1);
1085
1086 put_device(&v->dev);
1087}
1088
1089static struct vdpa_driver vhost_vdpa_driver = {
1090 .driver = {
1091 .name = "vhost_vdpa",
1092 },
1093 .probe = vhost_vdpa_probe,
1094 .remove = vhost_vdpa_remove,
1095};
1096
1097static int __init vhost_vdpa_init(void)
1098{
1099 int r;
1100
1101 r = alloc_chrdev_region(&vhost_vdpa_major, 0, VHOST_VDPA_DEV_MAX,
1102 "vhost-vdpa");
1103 if (r)
1104 goto err_alloc_chrdev;
1105
1106 r = vdpa_register_driver(&vhost_vdpa_driver);
1107 if (r)
1108 goto err_vdpa_register_driver;
1109
1110 return 0;
1111
1112err_vdpa_register_driver:
1113 unregister_chrdev_region(vhost_vdpa_major, VHOST_VDPA_DEV_MAX);
1114err_alloc_chrdev:
1115 return r;
1116}
1117module_init(vhost_vdpa_init);
1118
1119static void __exit vhost_vdpa_exit(void)
1120{
1121 vdpa_unregister_driver(&vhost_vdpa_driver);
1122 unregister_chrdev_region(vhost_vdpa_major, VHOST_VDPA_DEV_MAX);
1123}
1124module_exit(vhost_vdpa_exit);
1125
1126MODULE_VERSION("0.0.1");
1127MODULE_LICENSE("GPL v2");
1128MODULE_AUTHOR("Intel Corporation");
1129MODULE_DESCRIPTION("vDPA-based vhost backend for virtio");