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vhost: Fix documentation
[linux-block.git] / drivers / vhost / vdpa.c
CommitLineData
4c8cf318
TB		 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>
ddd89d0a 18#include <linux/mm.h>
4c8cf318
TB		 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>
776f3950 25#include <linux/kernel.h>
4c8cf318
TB		 26
27#include "vhost.h"
28
653055b9 29enum {
25abc060
JW		 30 VHOST_VDPA_BACKEND_FEATURES =
31 (1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2) |
32 (1ULL << VHOST_BACKEND_F_IOTLB_BATCH),
653055b9
JW		 33};
34
4c8cf318
TB		 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;
776f3950 49 struct eventfd_ctx *config_ctx;
25abc060 50 int in_batch;
4c8cf318
TB		 51};
52
53static DEFINE_IDA(vhost_vdpa_ida);
54
55static dev_t vhost_vdpa_major;
56
4c8cf318
TB		 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;
265a0ad8 70 struct eventfd_ctx *call_ctx = vq->call_ctx.ctx;
4c8cf318
TB		 71
72 if (call_ctx)
73 eventfd_signal(call_ctx, 1);
74
75 return IRQ_HANDLED;
76}
77
776f3950
ZL		 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
2cf1ba9a
ZL		 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
4c8cf318
TB		 122static void vhost_vdpa_reset(struct vhost_vdpa *v)
123{
124 struct vdpa_device *vdpa = v->vdpa;
4c8cf318 125
0d234007 126 vdpa_reset(vdpa);
25abc060 127 v->in_batch = 0;
4c8cf318
TB		 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;
2cf1ba9a
ZL		 162 u8 status, status_old;
163 int nvqs = v->nvqs;
164 u16 i;
4c8cf318
TB		 165
166 if (copy_from_user(&status, statusp, sizeof(status)))
167 return -EFAULT;
168
2cf1ba9a
ZL		 169 status_old = ops->get_status(vdpa);
170
4c8cf318
TB		 171 /*
172 * Userspace shouldn't remove status bits unless reset the
173 * status to 0.
174 */
175 if (status != 0 && (ops->get_status(vdpa) & ~status) != 0)
176 return -EINVAL;
177
178 ops->set_status(vdpa, status);
179
2cf1ba9a
ZL		 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
4c8cf318
TB		 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;
4c8cf318
TB		 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
0d234007 227 vdpa_get_config(vdpa, config.off, buf, config.len);
4c8cf318
TB		 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);
4c8cf318
TB		 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 * It's not allowed to change the features after they have
288 * been negotiated.
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
0d234007 296 if (vdpa_set_features(vdpa, features))
4c8cf318
TB		 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
776f3950
ZL		 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}
2cf1ba9a 346
4c8cf318
TB		 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;
aac50c0b 352 struct vdpa_vq_state vq_state;
4c8cf318
TB		 353 struct vdpa_callback cb;
354 struct vhost_virtqueue *vq;
355 struct vhost_vring_state s;
653055b9
JW		 356 u64 __user *featurep = argp;
357 u64 features;
4c8cf318
TB		 358 u32 idx;
359 long r;
360
361 r = get_user(idx, (u32 __user *)argp);
362 if (r < 0)
363 return r;
364
365 if (idx >= v->nvqs)
366 return -ENOBUFS;
367
368 idx = array_index_nospec(idx, v->nvqs);
369 vq = &v->vqs[idx];
370
b0bd82bf
JW		 371 switch (cmd) {
372 case VHOST_VDPA_SET_VRING_ENABLE:
4c8cf318
TB		 373 if (copy_from_user(&s, argp, sizeof(s)))
374 return -EFAULT;
375 ops->set_vq_ready(vdpa, idx, s.num);
376 return 0;
b0bd82bf 377 case VHOST_GET_VRING_BASE:
23750e39
EC		 378 r = ops->get_vq_state(v->vdpa, idx, &vq_state);
379 if (r)
380 return r;
381
aac50c0b 382 vq->last_avail_idx = vq_state.avail_index;
b0bd82bf 383 break;
653055b9
JW		 384 case VHOST_GET_BACKEND_FEATURES:
385 features = VHOST_VDPA_BACKEND_FEATURES;
386 if (copy_to_user(featurep, &features, sizeof(features)))
387 return -EFAULT;
388 return 0;
389 case VHOST_SET_BACKEND_FEATURES:
390 if (copy_from_user(&features, featurep, sizeof(features)))
391 return -EFAULT;
392 if (features & ~VHOST_VDPA_BACKEND_FEATURES)
393 return -EOPNOTSUPP;
394 vhost_set_backend_features(&v->vdev, features);
395 return 0;
b0bd82bf 396 }
4c8cf318
TB		 397
398 r = vhost_vring_ioctl(&v->vdev, cmd, argp);
399 if (r)
400 return r;
401
402 switch (cmd) {
403 case VHOST_SET_VRING_ADDR:
404 if (ops->set_vq_address(vdpa, idx,
405 (u64)(uintptr_t)vq->desc,
406 (u64)(uintptr_t)vq->avail,
407 (u64)(uintptr_t)vq->used))
408 r = -EINVAL;
409 break;
410
411 case VHOST_SET_VRING_BASE:
aac50c0b
EC		 412 vq_state.avail_index = vq->last_avail_idx;
413 if (ops->set_vq_state(vdpa, idx, &vq_state))
4c8cf318
TB		 414 r = -EINVAL;
415 break;
416
417 case VHOST_SET_VRING_CALL:
265a0ad8 418 if (vq->call_ctx.ctx) {
4c8cf318
TB		 419 cb.callback = vhost_vdpa_virtqueue_cb;
420 cb.private = vq;
421 } else {
422 cb.callback = NULL;
423 cb.private = NULL;
424 }
425 ops->set_vq_cb(vdpa, idx, &cb);
2cf1ba9a 426 vhost_vdpa_setup_vq_irq(v, idx);
4c8cf318
TB		 427 break;
428
429 case VHOST_SET_VRING_NUM:
430 ops->set_vq_num(vdpa, idx, vq->num);
431 break;
432 }
433
434 return r;
435}
436
437static long vhost_vdpa_unlocked_ioctl(struct file *filep,
438 unsigned int cmd, unsigned long arg)
439{
440 struct vhost_vdpa *v = filep->private_data;
441 struct vhost_dev *d = &v->vdev;
442 void __user *argp = (void __user *)arg;
443 long r;
444
445 mutex_lock(&d->mutex);
446
447 switch (cmd) {
448 case VHOST_VDPA_GET_DEVICE_ID:
449 r = vhost_vdpa_get_device_id(v, argp);
450 break;
451 case VHOST_VDPA_GET_STATUS:
452 r = vhost_vdpa_get_status(v, argp);
453 break;
454 case VHOST_VDPA_SET_STATUS:
455 r = vhost_vdpa_set_status(v, argp);
456 break;
457 case VHOST_VDPA_GET_CONFIG:
458 r = vhost_vdpa_get_config(v, argp);
459 break;
460 case VHOST_VDPA_SET_CONFIG:
461 r = vhost_vdpa_set_config(v, argp);
462 break;
463 case VHOST_GET_FEATURES:
464 r = vhost_vdpa_get_features(v, argp);
465 break;
466 case VHOST_SET_FEATURES:
467 r = vhost_vdpa_set_features(v, argp);
468 break;
469 case VHOST_VDPA_GET_VRING_NUM:
470 r = vhost_vdpa_get_vring_num(v, argp);
471 break;
472 case VHOST_SET_LOG_BASE:
473 case VHOST_SET_LOG_FD:
474 r = -ENOIOCTLCMD;
475 break;
776f3950
ZL		 476 case VHOST_VDPA_SET_CONFIG_CALL:
477 r = vhost_vdpa_set_config_call(v, argp);
478 break;
4c8cf318
TB		 479 default:
480 r = vhost_dev_ioctl(&v->vdev, cmd, argp);
481 if (r == -ENOIOCTLCMD)
482 r = vhost_vdpa_vring_ioctl(v, cmd, argp);
483 break;
484 }
485
486 mutex_unlock(&d->mutex);
487 return r;
488}
489
490static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last)
491{
492 struct vhost_dev *dev = &v->vdev;
493 struct vhost_iotlb *iotlb = dev->iotlb;
494 struct vhost_iotlb_map *map;
495 struct page *page;
496 unsigned long pfn, pinned;
497
498 while ((map = vhost_iotlb_itree_first(iotlb, start, last)) != NULL) {
499 pinned = map->size >> PAGE_SHIFT;
500 for (pfn = map->addr >> PAGE_SHIFT;
501 pinned > 0; pfn++, pinned--) {
502 page = pfn_to_page(pfn);
503 if (map->perm & VHOST_ACCESS_WO)
504 set_page_dirty_lock(page);
505 unpin_user_page(page);
506 }
507 atomic64_sub(map->size >> PAGE_SHIFT, &dev->mm->pinned_vm);
508 vhost_iotlb_map_free(iotlb, map);
509 }
510}
511
512static void vhost_vdpa_iotlb_free(struct vhost_vdpa *v)
513{
514 struct vhost_dev *dev = &v->vdev;
515
516 vhost_vdpa_iotlb_unmap(v, 0ULL, 0ULL - 1);
517 kfree(dev->iotlb);
518 dev->iotlb = NULL;
519}
520
521static int perm_to_iommu_flags(u32 perm)
522{
523 int flags = 0;
524
525 switch (perm) {
526 case VHOST_ACCESS_WO:
527 flags |= IOMMU_WRITE;
528 break;
529 case VHOST_ACCESS_RO:
530 flags |= IOMMU_READ;
531 break;
532 case VHOST_ACCESS_RW:
533 flags |= (IOMMU_WRITE | IOMMU_READ);
534 break;
535 default:
536 WARN(1, "invalidate vhost IOTLB permission\n");
537 break;
538 }
539
540 return flags | IOMMU_CACHE;
541}
542
543static int vhost_vdpa_map(struct vhost_vdpa *v,
544 u64 iova, u64 size, u64 pa, u32 perm)
545{
546 struct vhost_dev *dev = &v->vdev;
547 struct vdpa_device *vdpa = v->vdpa;
548 const struct vdpa_config_ops *ops = vdpa->config;
549 int r = 0;
550
551 r = vhost_iotlb_add_range(dev->iotlb, iova, iova + size - 1,
552 pa, perm);
553 if (r)
554 return r;
555
25abc060 556 if (ops->dma_map) {
4c8cf318 557 r = ops->dma_map(vdpa, iova, size, pa, perm);
25abc060
JW		 558 } else if (ops->set_map) {
559 if (!v->in_batch)
560 r = ops->set_map(vdpa, dev->iotlb);
561 } else {
4c8cf318
TB		 562 r = iommu_map(v->domain, iova, pa, size,
563 perm_to_iommu_flags(perm));
25abc060 564 }
4c8cf318
TB		 565
566 return r;
567}
568
569static void vhost_vdpa_unmap(struct vhost_vdpa *v, u64 iova, u64 size)
570{
571 struct vhost_dev *dev = &v->vdev;
572 struct vdpa_device *vdpa = v->vdpa;
573 const struct vdpa_config_ops *ops = vdpa->config;
574
575 vhost_vdpa_iotlb_unmap(v, iova, iova + size - 1);
576
25abc060 577 if (ops->dma_map) {
4c8cf318 578 ops->dma_unmap(vdpa, iova, size);
25abc060
JW		 579 } else if (ops->set_map) {
580 if (!v->in_batch)
581 ops->set_map(vdpa, dev->iotlb);
582 } else {
4c8cf318 583 iommu_unmap(v->domain, iova, size);
25abc060 584 }
4c8cf318
TB		 585}
586
587static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
588 struct vhost_iotlb_msg *msg)
589{
590 struct vhost_dev *dev = &v->vdev;
591 struct vhost_iotlb *iotlb = dev->iotlb;
592 struct page **page_list;
593 unsigned long list_size = PAGE_SIZE / sizeof(struct page *);
594 unsigned int gup_flags = FOLL_LONGTERM;
595 unsigned long npages, cur_base, map_pfn, last_pfn = 0;
596 unsigned long locked, lock_limit, pinned, i;
597 u64 iova = msg->iova;
598 int ret = 0;
599
600 if (vhost_iotlb_itree_first(iotlb, msg->iova,
601 msg->iova + msg->size - 1))
602 return -EEXIST;
603
604 page_list = (struct page **) __get_free_page(GFP_KERNEL);
605 if (!page_list)
606 return -ENOMEM;
607
608 if (msg->perm & VHOST_ACCESS_WO)
609 gup_flags |= FOLL_WRITE;
610
611 npages = PAGE_ALIGN(msg->size + (iova & ~PAGE_MASK)) >> PAGE_SHIFT;
612 if (!npages)
613 return -EINVAL;
614
d8ed45c5 615 mmap_read_lock(dev->mm);
4c8cf318
TB		 616
617 locked = atomic64_add_return(npages, &dev->mm->pinned_vm);
618 lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
619
620 if (locked > lock_limit) {
621 ret = -ENOMEM;
622 goto out;
623 }
624
625 cur_base = msg->uaddr & PAGE_MASK;
626 iova &= PAGE_MASK;
627
628 while (npages) {
629 pinned = min_t(unsigned long, npages, list_size);
630 ret = pin_user_pages(cur_base, pinned,
631 gup_flags, page_list, NULL);
632 if (ret != pinned)
633 goto out;
634
635 if (!last_pfn)
636 map_pfn = page_to_pfn(page_list[0]);
637
638 for (i = 0; i < ret; i++) {
639 unsigned long this_pfn = page_to_pfn(page_list[i]);
640 u64 csize;
641
642 if (last_pfn && (this_pfn != last_pfn + 1)) {
643 /* Pin a contiguous chunk of memory */
644 csize = (last_pfn - map_pfn + 1) << PAGE_SHIFT;
645 if (vhost_vdpa_map(v, iova, csize,
646 map_pfn << PAGE_SHIFT,
647 msg->perm))
648 goto out;
649 map_pfn = this_pfn;
650 iova += csize;
651 }
652
653 last_pfn = this_pfn;
654 }
655
656 cur_base += ret << PAGE_SHIFT;
657 npages -= ret;
658 }
659
660 /* Pin the rest chunk */
661 ret = vhost_vdpa_map(v, iova, (last_pfn - map_pfn + 1) << PAGE_SHIFT,
662 map_pfn << PAGE_SHIFT, msg->perm);
663out:
664 if (ret) {
665 vhost_vdpa_unmap(v, msg->iova, msg->size);
666 atomic64_sub(npages, &dev->mm->pinned_vm);
667 }
d8ed45c5 668 mmap_read_unlock(dev->mm);
4c8cf318
TB		 669 free_page((unsigned long)page_list);
670 return ret;
671}
672
673static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev,
674 struct vhost_iotlb_msg *msg)
675{
676 struct vhost_vdpa *v = container_of(dev, struct vhost_vdpa, vdev);
25abc060
JW		 677 struct vdpa_device *vdpa = v->vdpa;
678 const struct vdpa_config_ops *ops = vdpa->config;
4c8cf318
TB		 679 int r = 0;
680
681 r = vhost_dev_check_owner(dev);
682 if (r)
683 return r;
684
685 switch (msg->type) {
686 case VHOST_IOTLB_UPDATE:
687 r = vhost_vdpa_process_iotlb_update(v, msg);
688 break;
689 case VHOST_IOTLB_INVALIDATE:
690 vhost_vdpa_unmap(v, msg->iova, msg->size);
691 break;
25abc060
JW		 692 case VHOST_IOTLB_BATCH_BEGIN:
693 v->in_batch = true;
694 break;
695 case VHOST_IOTLB_BATCH_END:
696 if (v->in_batch && ops->set_map)
697 ops->set_map(vdpa, dev->iotlb);
698 v->in_batch = false;
699 break;
4c8cf318
TB		 700 default:
701 r = -EINVAL;
702 break;
703 }
704
705 return r;
706}
707
708static ssize_t vhost_vdpa_chr_write_iter(struct kiocb *iocb,
709 struct iov_iter *from)
710{
711 struct file *file = iocb->ki_filp;
712 struct vhost_vdpa *v = file->private_data;
713 struct vhost_dev *dev = &v->vdev;
714
715 return vhost_chr_write_iter(dev, from);
716}
717
718static int vhost_vdpa_alloc_domain(struct vhost_vdpa *v)
719{
720 struct vdpa_device *vdpa = v->vdpa;
721 const struct vdpa_config_ops *ops = vdpa->config;
722 struct device *dma_dev = vdpa_get_dma_dev(vdpa);
723 struct bus_type *bus;
724 int ret;
725
726 /* Device want to do DMA by itself */
727 if (ops->set_map || ops->dma_map)
728 return 0;
729
730 bus = dma_dev->bus;
731 if (!bus)
732 return -EFAULT;
733
734 if (!iommu_capable(bus, IOMMU_CAP_CACHE_COHERENCY))
735 return -ENOTSUPP;
736
737 v->domain = iommu_domain_alloc(bus);
738 if (!v->domain)
739 return -EIO;
740
741 ret = iommu_attach_device(v->domain, dma_dev);
742 if (ret)
743 goto err_attach;
744
745 return 0;
746
747err_attach:
748 iommu_domain_free(v->domain);
749 return ret;
750}
751
752static void vhost_vdpa_free_domain(struct vhost_vdpa *v)
753{
754 struct vdpa_device *vdpa = v->vdpa;
755 struct device *dma_dev = vdpa_get_dma_dev(vdpa);
756
757 if (v->domain) {
758 iommu_detach_device(v->domain, dma_dev);
759 iommu_domain_free(v->domain);
760 }
761
762 v->domain = NULL;
763}
764
765static int vhost_vdpa_open(struct inode *inode, struct file *filep)
766{
767 struct vhost_vdpa *v;
768 struct vhost_dev *dev;
769 struct vhost_virtqueue **vqs;
770 int nvqs, i, r, opened;
771
772 v = container_of(inode->i_cdev, struct vhost_vdpa, cdev);
4c8cf318
TB		 773
774 opened = atomic_cmpxchg(&v->opened, 0, 1);
775 if (opened)
776 return -EBUSY;
777
778 nvqs = v->nvqs;
779 vhost_vdpa_reset(v);
780
781 vqs = kmalloc_array(nvqs, sizeof(*vqs), GFP_KERNEL);
782 if (!vqs) {
783 r = -ENOMEM;
784 goto err;
785 }
786
787 dev = &v->vdev;
788 for (i = 0; i < nvqs; i++) {
789 vqs[i] = &v->vqs[i];
790 vqs[i]->handle_kick = handle_vq_kick;
791 }
01fcb1cb 792 vhost_dev_init(dev, vqs, nvqs, 0, 0, 0, false,
4c8cf318
TB		 793 vhost_vdpa_process_iotlb_msg);
794
795 dev->iotlb = vhost_iotlb_alloc(0, 0);
796 if (!dev->iotlb) {
797 r = -ENOMEM;
798 goto err_init_iotlb;
799 }
800
801 r = vhost_vdpa_alloc_domain(v);
802 if (r)
803 goto err_init_iotlb;
804
805 filep->private_data = v;
806
807 return 0;
808
809err_init_iotlb:
810 vhost_dev_cleanup(&v->vdev);
811err:
812 atomic_dec(&v->opened);
813 return r;
814}
815
2cf1ba9a
ZL		 816static void vhost_vdpa_clean_irq(struct vhost_vdpa *v)
817{
818 struct vhost_virtqueue *vq;
819 int i;
820
821 for (i = 0; i < v->nvqs; i++) {
822 vq = &v->vqs[i];
823 if (vq->call_ctx.producer.irq)
824 irq_bypass_unregister_producer(&vq->call_ctx.producer);
825 }
826}
827
4c8cf318
TB		 828static int vhost_vdpa_release(struct inode *inode, struct file *filep)
829{
830 struct vhost_vdpa *v = filep->private_data;
831 struct vhost_dev *d = &v->vdev;
832
833 mutex_lock(&d->mutex);
834 filep->private_data = NULL;
835 vhost_vdpa_reset(v);
836 vhost_dev_stop(&v->vdev);
837 vhost_vdpa_iotlb_free(v);
838 vhost_vdpa_free_domain(v);
776f3950 839 vhost_vdpa_config_put(v);
2cf1ba9a 840 vhost_vdpa_clean_irq(v);
4c8cf318
TB		 841 vhost_dev_cleanup(&v->vdev);
842 kfree(v->vdev.vqs);
843 mutex_unlock(&d->mutex);
844
845 atomic_dec(&v->opened);
846 complete(&v->completion);
847
848 return 0;
849}
850
4b4e4867 851#ifdef CONFIG_MMU
ddd89d0a
JW		 852static vm_fault_t vhost_vdpa_fault(struct vm_fault *vmf)
853{
854 struct vhost_vdpa *v = vmf->vma->vm_file->private_data;
855 struct vdpa_device *vdpa = v->vdpa;
856 const struct vdpa_config_ops *ops = vdpa->config;
857 struct vdpa_notification_area notify;
858 struct vm_area_struct *vma = vmf->vma;
859 u16 index = vma->vm_pgoff;
860
861 notify = ops->get_vq_notification(vdpa, index);
862
863 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
864 if (remap_pfn_range(vma, vmf->address & PAGE_MASK,
865 notify.addr >> PAGE_SHIFT, PAGE_SIZE,
866 vma->vm_page_prot))
867 return VM_FAULT_SIGBUS;
868
869 return VM_FAULT_NOPAGE;
870}
871
872static const struct vm_operations_struct vhost_vdpa_vm_ops = {
873 .fault = vhost_vdpa_fault,
874};
875
876static int vhost_vdpa_mmap(struct file *file, struct vm_area_struct *vma)
877{
878 struct vhost_vdpa *v = vma->vm_file->private_data;
879 struct vdpa_device *vdpa = v->vdpa;
880 const struct vdpa_config_ops *ops = vdpa->config;
881 struct vdpa_notification_area notify;
c09cc2c3 882 unsigned long index = vma->vm_pgoff;
ddd89d0a
JW		 883
884 if (vma->vm_end - vma->vm_start != PAGE_SIZE)
885 return -EINVAL;
886 if ((vma->vm_flags & VM_SHARED) == 0)
887 return -EINVAL;
888 if (vma->vm_flags & VM_READ)
889 return -EINVAL;
890 if (index > 65535)
891 return -EINVAL;
892 if (!ops->get_vq_notification)
893 return -ENOTSUPP;
894
895 /* To be safe and easily modelled by userspace, We only
896 * support the doorbell which sits on the page boundary and
897 * does not share the page with other registers.
898 */
899 notify = ops->get_vq_notification(vdpa, index);
900 if (notify.addr & (PAGE_SIZE - 1))
901 return -EINVAL;
902 if (vma->vm_end - vma->vm_start != notify.size)
903 return -ENOTSUPP;
904
905 vma->vm_ops = &vhost_vdpa_vm_ops;
906 return 0;
907}
4b4e4867 908#endif /* CONFIG_MMU */
ddd89d0a 909
4c8cf318
TB		 910static const struct file_operations vhost_vdpa_fops = {
911 .owner = THIS_MODULE,
912 .open = vhost_vdpa_open,
913 .release = vhost_vdpa_release,
914 .write_iter = vhost_vdpa_chr_write_iter,
915 .unlocked_ioctl = vhost_vdpa_unlocked_ioctl,
4b4e4867 916#ifdef CONFIG_MMU
ddd89d0a 917 .mmap = vhost_vdpa_mmap,
4b4e4867 918#endif /* CONFIG_MMU */
4c8cf318
TB		 919 .compat_ioctl = compat_ptr_ioctl,
920};
921
922static void vhost_vdpa_release_dev(struct device *device)
923{
924 struct vhost_vdpa *v =
925 container_of(device, struct vhost_vdpa, dev);
926
927 ida_simple_remove(&vhost_vdpa_ida, v->minor);
928 kfree(v->vqs);
929 kfree(v);
930}
931
932static int vhost_vdpa_probe(struct vdpa_device *vdpa)
933{
934 const struct vdpa_config_ops *ops = vdpa->config;
935 struct vhost_vdpa *v;
a9974489 936 int minor;
4c8cf318
TB		 937 int r;
938
939 /* Currently, we only accept the network devices. */
940 if (ops->get_device_id(vdpa) != VIRTIO_ID_NET)
941 return -ENOTSUPP;
942
943 v = kzalloc(sizeof(*v), GFP_KERNEL | __GFP_RETRY_MAYFAIL);
944 if (!v)
945 return -ENOMEM;
946
947 minor = ida_simple_get(&vhost_vdpa_ida, 0,
948 VHOST_VDPA_DEV_MAX, GFP_KERNEL);
949 if (minor < 0) {
950 kfree(v);
951 return minor;
952 }
953
954 atomic_set(&v->opened, 0);
955 v->minor = minor;
956 v->vdpa = vdpa;
a9974489 957 v->nvqs = vdpa->nvqs;
4c8cf318
TB		 958 v->virtio_id = ops->get_device_id(vdpa);
959
960 device_initialize(&v->dev);
961 v->dev.release = vhost_vdpa_release_dev;
962 v->dev.parent = &vdpa->dev;
963 v->dev.devt = MKDEV(MAJOR(vhost_vdpa_major), minor);
a9974489 964 v->vqs = kmalloc_array(v->nvqs, sizeof(struct vhost_virtqueue),
4c8cf318
TB		 965 GFP_KERNEL);
966 if (!v->vqs) {
967 r = -ENOMEM;
968 goto err;
969 }
970
971 r = dev_set_name(&v->dev, "vhost-vdpa-%u", minor);
972 if (r)
973 goto err;
974
975 cdev_init(&v->cdev, &vhost_vdpa_fops);
976 v->cdev.owner = THIS_MODULE;
977
978 r = cdev_device_add(&v->cdev, &v->dev);
979 if (r)
980 goto err;
981
982 init_completion(&v->completion);
983 vdpa_set_drvdata(vdpa, v);
984
985 return 0;
986
987err:
988 put_device(&v->dev);
989 return r;
990}
991
992static void vhost_vdpa_remove(struct vdpa_device *vdpa)
993{
994 struct vhost_vdpa *v = vdpa_get_drvdata(vdpa);
995 int opened;
996
997 cdev_device_del(&v->cdev, &v->dev);
998
999 do {
1000 opened = atomic_cmpxchg(&v->opened, 0, 1);
1001 if (!opened)
1002 break;
1003 wait_for_completion(&v->completion);
1004 } while (1);
1005
1006 put_device(&v->dev);
1007}
1008
1009static struct vdpa_driver vhost_vdpa_driver = {
1010 .driver = {
1011 .name = "vhost_vdpa",
1012 },
1013 .probe = vhost_vdpa_probe,
1014 .remove = vhost_vdpa_remove,
1015};
1016
1017static int __init vhost_vdpa_init(void)
1018{
1019 int r;
1020
1021 r = alloc_chrdev_region(&vhost_vdpa_major, 0, VHOST_VDPA_DEV_MAX,
1022 "vhost-vdpa");
1023 if (r)
1024 goto err_alloc_chrdev;
1025
1026 r = vdpa_register_driver(&vhost_vdpa_driver);
1027 if (r)
1028 goto err_vdpa_register_driver;
1029
1030 return 0;
1031
1032err_vdpa_register_driver:
1033 unregister_chrdev_region(vhost_vdpa_major, VHOST_VDPA_DEV_MAX);
1034err_alloc_chrdev:
1035 return r;
1036}
1037module_init(vhost_vdpa_init);
1038
1039static void __exit vhost_vdpa_exit(void)
1040{
1041 vdpa_unregister_driver(&vhost_vdpa_driver);
1042 unregister_chrdev_region(vhost_vdpa_major, VHOST_VDPA_DEV_MAX);
1043}
1044module_exit(vhost_vdpa_exit);
1045
1046MODULE_VERSION("0.0.1");
1047MODULE_LICENSE("GPL v2");
1048MODULE_AUTHOR("Intel Corporation");
1049MODULE_DESCRIPTION("vDPA-based vhost backend for virtio");
Linux 6.x block layer and io_uring tree(s)