1
2
3
4
5
6
7
8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10#include <linux/amba/bus.h>
11#include <linux/delay.h>
12#include <linux/dma-iommu.h>
13#include <linux/dma-map-ops.h>
14#include <linux/freezer.h>
15#include <linux/interval_tree.h>
16#include <linux/iommu.h>
17#include <linux/module.h>
18#include <linux/of_platform.h>
19#include <linux/pci.h>
20#include <linux/platform_device.h>
21#include <linux/virtio.h>
22#include <linux/virtio_config.h>
23#include <linux/virtio_ids.h>
24#include <linux/wait.h>
25
26#include <uapi/linux/virtio_iommu.h>
27
28#define MSI_IOVA_BASE 0x8000000
29#define MSI_IOVA_LENGTH 0x100000
30
31#define VIOMMU_REQUEST_VQ 0
32#define VIOMMU_EVENT_VQ 1
33#define VIOMMU_NR_VQS 2
34
35struct viommu_dev {
36 struct iommu_device iommu;
37 struct device *dev;
38 struct virtio_device *vdev;
39
40 struct ida domain_ids;
41
42 struct virtqueue *vqs[VIOMMU_NR_VQS];
43 spinlock_t request_lock;
44 struct list_head requests;
45 void *evts;
46
47
48 struct iommu_domain_geometry geometry;
49 u64 pgsize_bitmap;
50 u32 first_domain;
51 u32 last_domain;
52
53 u32 map_flags;
54 u32 probe_size;
55};
56
57struct viommu_mapping {
58 phys_addr_t paddr;
59 struct interval_tree_node iova;
60 u32 flags;
61};
62
63struct viommu_domain {
64 struct iommu_domain domain;
65 struct viommu_dev *viommu;
66 struct mutex mutex;
67 unsigned int id;
68 u32 map_flags;
69
70 spinlock_t mappings_lock;
71 struct rb_root_cached mappings;
72
73 unsigned long nr_endpoints;
74 bool bypass;
75};
76
77struct viommu_endpoint {
78 struct device *dev;
79 struct viommu_dev *viommu;
80 struct viommu_domain *vdomain;
81 struct list_head resv_regions;
82};
83
84struct viommu_request {
85 struct list_head list;
86 void *writeback;
87 unsigned int write_offset;
88 unsigned int len;
89 char buf[];
90};
91
92#define VIOMMU_FAULT_RESV_MASK 0xffffff00
93
94struct viommu_event {
95 union {
96 u32 head;
97 struct virtio_iommu_fault fault;
98 };
99};
100
101#define to_viommu_domain(domain) \
102 container_of(domain, struct viommu_domain, domain)
103
104static int viommu_get_req_errno(void *buf, size_t len)
105{
106 struct virtio_iommu_req_tail *tail = buf + len - sizeof(*tail);
107
108 switch (tail->status) {
109 case VIRTIO_IOMMU_S_OK:
110 return 0;
111 case VIRTIO_IOMMU_S_UNSUPP:
112 return -ENOSYS;
113 case VIRTIO_IOMMU_S_INVAL:
114 return -EINVAL;
115 case VIRTIO_IOMMU_S_RANGE:
116 return -ERANGE;
117 case VIRTIO_IOMMU_S_NOENT:
118 return -ENOENT;
119 case VIRTIO_IOMMU_S_FAULT:
120 return -EFAULT;
121 case VIRTIO_IOMMU_S_NOMEM:
122 return -ENOMEM;
123 case VIRTIO_IOMMU_S_IOERR:
124 case VIRTIO_IOMMU_S_DEVERR:
125 default:
126 return -EIO;
127 }
128}
129
130static void viommu_set_req_status(void *buf, size_t len, int status)
131{
132 struct virtio_iommu_req_tail *tail = buf + len - sizeof(*tail);
133
134 tail->status = status;
135}
136
137static off_t viommu_get_write_desc_offset(struct viommu_dev *viommu,
138 struct virtio_iommu_req_head *req,
139 size_t len)
140{
141 size_t tail_size = sizeof(struct virtio_iommu_req_tail);
142
143 if (req->type == VIRTIO_IOMMU_T_PROBE)
144 return len - viommu->probe_size - tail_size;
145
146 return len - tail_size;
147}
148
149
150
151
152
153
154
155static int __viommu_sync_req(struct viommu_dev *viommu)
156{
157 unsigned int len;
158 size_t write_len;
159 struct viommu_request *req;
160 struct virtqueue *vq = viommu->vqs[VIOMMU_REQUEST_VQ];
161
162 assert_spin_locked(&viommu->request_lock);
163
164 virtqueue_kick(vq);
165
166 while (!list_empty(&viommu->requests)) {
167 len = 0;
168 req = virtqueue_get_buf(vq, &len);
169 if (!req)
170 continue;
171
172 if (!len)
173 viommu_set_req_status(req->buf, req->len,
174 VIRTIO_IOMMU_S_IOERR);
175
176 write_len = req->len - req->write_offset;
177 if (req->writeback && len == write_len)
178 memcpy(req->writeback, req->buf + req->write_offset,
179 write_len);
180
181 list_del(&req->list);
182 kfree(req);
183 }
184
185 return 0;
186}
187
188static int viommu_sync_req(struct viommu_dev *viommu)
189{
190 int ret;
191 unsigned long flags;
192
193 spin_lock_irqsave(&viommu->request_lock, flags);
194 ret = __viommu_sync_req(viommu);
195 if (ret)
196 dev_dbg(viommu->dev, "could not sync requests (%d)\n", ret);
197 spin_unlock_irqrestore(&viommu->request_lock, flags);
198
199 return ret;
200}
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218static int __viommu_add_req(struct viommu_dev *viommu, void *buf, size_t len,
219 bool writeback)
220{
221 int ret;
222 off_t write_offset;
223 struct viommu_request *req;
224 struct scatterlist top_sg, bottom_sg;
225 struct scatterlist *sg[2] = { &top_sg, &bottom_sg };
226 struct virtqueue *vq = viommu->vqs[VIOMMU_REQUEST_VQ];
227
228 assert_spin_locked(&viommu->request_lock);
229
230 write_offset = viommu_get_write_desc_offset(viommu, buf, len);
231 if (write_offset <= 0)
232 return -EINVAL;
233
234 req = kzalloc(sizeof(*req) + len, GFP_ATOMIC);
235 if (!req)
236 return -ENOMEM;
237
238 req->len = len;
239 if (writeback) {
240 req->writeback = buf + write_offset;
241 req->write_offset = write_offset;
242 }
243 memcpy(&req->buf, buf, write_offset);
244
245 sg_init_one(&top_sg, req->buf, write_offset);
246 sg_init_one(&bottom_sg, req->buf + write_offset, len - write_offset);
247
248 ret = virtqueue_add_sgs(vq, sg, 1, 1, req, GFP_ATOMIC);
249 if (ret == -ENOSPC) {
250
251 if (!__viommu_sync_req(viommu))
252 ret = virtqueue_add_sgs(vq, sg, 1, 1, req, GFP_ATOMIC);
253 }
254 if (ret)
255 goto err_free;
256
257 list_add_tail(&req->list, &viommu->requests);
258 return 0;
259
260err_free:
261 kfree(req);
262 return ret;
263}
264
265static int viommu_add_req(struct viommu_dev *viommu, void *buf, size_t len)
266{
267 int ret;
268 unsigned long flags;
269
270 spin_lock_irqsave(&viommu->request_lock, flags);
271 ret = __viommu_add_req(viommu, buf, len, false);
272 if (ret)
273 dev_dbg(viommu->dev, "could not add request: %d\n", ret);
274 spin_unlock_irqrestore(&viommu->request_lock, flags);
275
276 return ret;
277}
278
279
280
281
282
283static int viommu_send_req_sync(struct viommu_dev *viommu, void *buf,
284 size_t len)
285{
286 int ret;
287 unsigned long flags;
288
289 spin_lock_irqsave(&viommu->request_lock, flags);
290
291 ret = __viommu_add_req(viommu, buf, len, true);
292 if (ret) {
293 dev_dbg(viommu->dev, "could not add request (%d)\n", ret);
294 goto out_unlock;
295 }
296
297 ret = __viommu_sync_req(viommu);
298 if (ret) {
299 dev_dbg(viommu->dev, "could not sync requests (%d)\n", ret);
300
301 }
302
303 ret = viommu_get_req_errno(buf, len);
304out_unlock:
305 spin_unlock_irqrestore(&viommu->request_lock, flags);
306 return ret;
307}
308
309
310
311
312
313
314static int viommu_add_mapping(struct viommu_domain *vdomain, u64 iova, u64 end,
315 phys_addr_t paddr, u32 flags)
316{
317 unsigned long irqflags;
318 struct viommu_mapping *mapping;
319
320 mapping = kzalloc(sizeof(*mapping), GFP_ATOMIC);
321 if (!mapping)
322 return -ENOMEM;
323
324 mapping->paddr = paddr;
325 mapping->iova.start = iova;
326 mapping->iova.last = end;
327 mapping->flags = flags;
328
329 spin_lock_irqsave(&vdomain->mappings_lock, irqflags);
330 interval_tree_insert(&mapping->iova, &vdomain->mappings);
331 spin_unlock_irqrestore(&vdomain->mappings_lock, irqflags);
332
333 return 0;
334}
335
336
337
338
339
340
341
342
343
344
345static size_t viommu_del_mappings(struct viommu_domain *vdomain,
346 u64 iova, u64 end)
347{
348 size_t unmapped = 0;
349 unsigned long flags;
350 struct viommu_mapping *mapping = NULL;
351 struct interval_tree_node *node, *next;
352
353 spin_lock_irqsave(&vdomain->mappings_lock, flags);
354 next = interval_tree_iter_first(&vdomain->mappings, iova, end);
355 while (next) {
356 node = next;
357 mapping = container_of(node, struct viommu_mapping, iova);
358 next = interval_tree_iter_next(node, iova, end);
359
360
361 if (mapping->iova.start < iova)
362 break;
363
364
365
366
367
368 unmapped += mapping->iova.last - mapping->iova.start + 1;
369
370 interval_tree_remove(node, &vdomain->mappings);
371 kfree(mapping);
372 }
373 spin_unlock_irqrestore(&vdomain->mappings_lock, flags);
374
375 return unmapped;
376}
377
378
379
380
381
382static int viommu_domain_map_identity(struct viommu_endpoint *vdev,
383 struct viommu_domain *vdomain)
384{
385 int ret;
386 struct iommu_resv_region *resv;
387 u64 iova = vdomain->domain.geometry.aperture_start;
388 u64 limit = vdomain->domain.geometry.aperture_end;
389 u32 flags = VIRTIO_IOMMU_MAP_F_READ | VIRTIO_IOMMU_MAP_F_WRITE;
390 unsigned long granule = 1UL << __ffs(vdomain->domain.pgsize_bitmap);
391
392 iova = ALIGN(iova, granule);
393 limit = ALIGN_DOWN(limit + 1, granule) - 1;
394
395 list_for_each_entry(resv, &vdev->resv_regions, list) {
396 u64 resv_start = ALIGN_DOWN(resv->start, granule);
397 u64 resv_end = ALIGN(resv->start + resv->length, granule) - 1;
398
399 if (resv_end < iova || resv_start > limit)
400
401 continue;
402
403 if (resv_start > iova) {
404 ret = viommu_add_mapping(vdomain, iova, resv_start - 1,
405 (phys_addr_t)iova, flags);
406 if (ret)
407 goto err_unmap;
408 }
409
410 if (resv_end >= limit)
411 return 0;
412
413 iova = resv_end + 1;
414 }
415
416 ret = viommu_add_mapping(vdomain, iova, limit, (phys_addr_t)iova,
417 flags);
418 if (ret)
419 goto err_unmap;
420 return 0;
421
422err_unmap:
423 viommu_del_mappings(vdomain, 0, iova);
424 return ret;
425}
426
427
428
429
430
431
432
433
434static int viommu_replay_mappings(struct viommu_domain *vdomain)
435{
436 int ret = 0;
437 unsigned long flags;
438 struct viommu_mapping *mapping;
439 struct interval_tree_node *node;
440 struct virtio_iommu_req_map map;
441
442 spin_lock_irqsave(&vdomain->mappings_lock, flags);
443 node = interval_tree_iter_first(&vdomain->mappings, 0, -1UL);
444 while (node) {
445 mapping = container_of(node, struct viommu_mapping, iova);
446 map = (struct virtio_iommu_req_map) {
447 .head.type = VIRTIO_IOMMU_T_MAP,
448 .domain = cpu_to_le32(vdomain->id),
449 .virt_start = cpu_to_le64(mapping->iova.start),
450 .virt_end = cpu_to_le64(mapping->iova.last),
451 .phys_start = cpu_to_le64(mapping->paddr),
452 .flags = cpu_to_le32(mapping->flags),
453 };
454
455 ret = viommu_send_req_sync(vdomain->viommu, &map, sizeof(map));
456 if (ret)
457 break;
458
459 node = interval_tree_iter_next(node, 0, -1UL);
460 }
461 spin_unlock_irqrestore(&vdomain->mappings_lock, flags);
462
463 return ret;
464}
465
466static int viommu_add_resv_mem(struct viommu_endpoint *vdev,
467 struct virtio_iommu_probe_resv_mem *mem,
468 size_t len)
469{
470 size_t size;
471 u64 start64, end64;
472 phys_addr_t start, end;
473 struct iommu_resv_region *region = NULL, *next;
474 unsigned long prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO;
475
476 start = start64 = le64_to_cpu(mem->start);
477 end = end64 = le64_to_cpu(mem->end);
478 size = end64 - start64 + 1;
479
480
481 if (start != start64 || end != end64 || size < end64 - start64)
482 return -EOVERFLOW;
483
484 if (len < sizeof(*mem))
485 return -EINVAL;
486
487 switch (mem->subtype) {
488 default:
489 dev_warn(vdev->dev, "unknown resv mem subtype 0x%x\n",
490 mem->subtype);
491 fallthrough;
492 case VIRTIO_IOMMU_RESV_MEM_T_RESERVED:
493 region = iommu_alloc_resv_region(start, size, 0,
494 IOMMU_RESV_RESERVED);
495 break;
496 case VIRTIO_IOMMU_RESV_MEM_T_MSI:
497 region = iommu_alloc_resv_region(start, size, prot,
498 IOMMU_RESV_MSI);
499 break;
500 }
501 if (!region)
502 return -ENOMEM;
503
504
505 list_for_each_entry(next, &vdev->resv_regions, list) {
506 if (next->start > region->start)
507 break;
508 }
509 list_add_tail(®ion->list, &next->list);
510 return 0;
511}
512
513static int viommu_probe_endpoint(struct viommu_dev *viommu, struct device *dev)
514{
515 int ret;
516 u16 type, len;
517 size_t cur = 0;
518 size_t probe_len;
519 struct virtio_iommu_req_probe *probe;
520 struct virtio_iommu_probe_property *prop;
521 struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
522 struct viommu_endpoint *vdev = dev_iommu_priv_get(dev);
523
524 if (!fwspec->num_ids)
525 return -EINVAL;
526
527 probe_len = sizeof(*probe) + viommu->probe_size +
528 sizeof(struct virtio_iommu_req_tail);
529 probe = kzalloc(probe_len, GFP_KERNEL);
530 if (!probe)
531 return -ENOMEM;
532
533 probe->head.type = VIRTIO_IOMMU_T_PROBE;
534
535
536
537
538 probe->endpoint = cpu_to_le32(fwspec->ids[0]);
539
540 ret = viommu_send_req_sync(viommu, probe, probe_len);
541 if (ret)
542 goto out_free;
543
544 prop = (void *)probe->properties;
545 type = le16_to_cpu(prop->type) & VIRTIO_IOMMU_PROBE_T_MASK;
546
547 while (type != VIRTIO_IOMMU_PROBE_T_NONE &&
548 cur < viommu->probe_size) {
549 len = le16_to_cpu(prop->length) + sizeof(*prop);
550
551 switch (type) {
552 case VIRTIO_IOMMU_PROBE_T_RESV_MEM:
553 ret = viommu_add_resv_mem(vdev, (void *)prop, len);
554 break;
555 default:
556 dev_err(dev, "unknown viommu prop 0x%x\n", type);
557 }
558
559 if (ret)
560 dev_err(dev, "failed to parse viommu prop 0x%x\n", type);
561
562 cur += len;
563 if (cur >= viommu->probe_size)
564 break;
565
566 prop = (void *)probe->properties + cur;
567 type = le16_to_cpu(prop->type) & VIRTIO_IOMMU_PROBE_T_MASK;
568 }
569
570out_free:
571 kfree(probe);
572 return ret;
573}
574
575static int viommu_fault_handler(struct viommu_dev *viommu,
576 struct virtio_iommu_fault *fault)
577{
578 char *reason_str;
579
580 u8 reason = fault->reason;
581 u32 flags = le32_to_cpu(fault->flags);
582 u32 endpoint = le32_to_cpu(fault->endpoint);
583 u64 address = le64_to_cpu(fault->address);
584
585 switch (reason) {
586 case VIRTIO_IOMMU_FAULT_R_DOMAIN:
587 reason_str = "domain";
588 break;
589 case VIRTIO_IOMMU_FAULT_R_MAPPING:
590 reason_str = "page";
591 break;
592 case VIRTIO_IOMMU_FAULT_R_UNKNOWN:
593 default:
594 reason_str = "unknown";
595 break;
596 }
597
598
599 if (flags & VIRTIO_IOMMU_FAULT_F_ADDRESS)
600 dev_err_ratelimited(viommu->dev, "%s fault from EP %u at %#llx [%s%s%s]\n",
601 reason_str, endpoint, address,
602 flags & VIRTIO_IOMMU_FAULT_F_READ ? "R" : "",
603 flags & VIRTIO_IOMMU_FAULT_F_WRITE ? "W" : "",
604 flags & VIRTIO_IOMMU_FAULT_F_EXEC ? "X" : "");
605 else
606 dev_err_ratelimited(viommu->dev, "%s fault from EP %u\n",
607 reason_str, endpoint);
608 return 0;
609}
610
611static void viommu_event_handler(struct virtqueue *vq)
612{
613 int ret;
614 unsigned int len;
615 struct scatterlist sg[1];
616 struct viommu_event *evt;
617 struct viommu_dev *viommu = vq->vdev->priv;
618
619 while ((evt = virtqueue_get_buf(vq, &len)) != NULL) {
620 if (len > sizeof(*evt)) {
621 dev_err(viommu->dev,
622 "invalid event buffer (len %u != %zu)\n",
623 len, sizeof(*evt));
624 } else if (!(evt->head & VIOMMU_FAULT_RESV_MASK)) {
625 viommu_fault_handler(viommu, &evt->fault);
626 }
627
628 sg_init_one(sg, evt, sizeof(*evt));
629 ret = virtqueue_add_inbuf(vq, sg, 1, evt, GFP_ATOMIC);
630 if (ret)
631 dev_err(viommu->dev, "could not add event buffer\n");
632 }
633
634 virtqueue_kick(vq);
635}
636
637
638
639static struct iommu_domain *viommu_domain_alloc(unsigned type)
640{
641 struct viommu_domain *vdomain;
642
643 if (type != IOMMU_DOMAIN_UNMANAGED &&
644 type != IOMMU_DOMAIN_DMA &&
645 type != IOMMU_DOMAIN_IDENTITY)
646 return NULL;
647
648 vdomain = kzalloc(sizeof(*vdomain), GFP_KERNEL);
649 if (!vdomain)
650 return NULL;
651
652 mutex_init(&vdomain->mutex);
653 spin_lock_init(&vdomain->mappings_lock);
654 vdomain->mappings = RB_ROOT_CACHED;
655
656 return &vdomain->domain;
657}
658
659static int viommu_domain_finalise(struct viommu_endpoint *vdev,
660 struct iommu_domain *domain)
661{
662 int ret;
663 unsigned long viommu_page_size;
664 struct viommu_dev *viommu = vdev->viommu;
665 struct viommu_domain *vdomain = to_viommu_domain(domain);
666
667 viommu_page_size = 1UL << __ffs(viommu->pgsize_bitmap);
668 if (viommu_page_size > PAGE_SIZE) {
669 dev_err(vdev->dev,
670 "granule 0x%lx larger than system page size 0x%lx\n",
671 viommu_page_size, PAGE_SIZE);
672 return -EINVAL;
673 }
674
675 ret = ida_alloc_range(&viommu->domain_ids, viommu->first_domain,
676 viommu->last_domain, GFP_KERNEL);
677 if (ret < 0)
678 return ret;
679
680 vdomain->id = (unsigned int)ret;
681
682 domain->pgsize_bitmap = viommu->pgsize_bitmap;
683 domain->geometry = viommu->geometry;
684
685 vdomain->map_flags = viommu->map_flags;
686 vdomain->viommu = viommu;
687
688 if (domain->type == IOMMU_DOMAIN_IDENTITY) {
689 if (virtio_has_feature(viommu->vdev,
690 VIRTIO_IOMMU_F_BYPASS_CONFIG)) {
691 vdomain->bypass = true;
692 return 0;
693 }
694
695 ret = viommu_domain_map_identity(vdev, vdomain);
696 if (ret) {
697 ida_free(&viommu->domain_ids, vdomain->id);
698 vdomain->viommu = NULL;
699 return -EOPNOTSUPP;
700 }
701 }
702
703 return 0;
704}
705
706static void viommu_domain_free(struct iommu_domain *domain)
707{
708 struct viommu_domain *vdomain = to_viommu_domain(domain);
709
710
711 viommu_del_mappings(vdomain, 0, ULLONG_MAX);
712
713 if (vdomain->viommu)
714 ida_free(&vdomain->viommu->domain_ids, vdomain->id);
715
716 kfree(vdomain);
717}
718
719static int viommu_attach_dev(struct iommu_domain *domain, struct device *dev)
720{
721 int i;
722 int ret = 0;
723 struct virtio_iommu_req_attach req;
724 struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
725 struct viommu_endpoint *vdev = dev_iommu_priv_get(dev);
726 struct viommu_domain *vdomain = to_viommu_domain(domain);
727
728 mutex_lock(&vdomain->mutex);
729 if (!vdomain->viommu) {
730
731
732
733
734 ret = viommu_domain_finalise(vdev, domain);
735 } else if (vdomain->viommu != vdev->viommu) {
736 dev_err(dev, "cannot attach to foreign vIOMMU\n");
737 ret = -EXDEV;
738 }
739 mutex_unlock(&vdomain->mutex);
740
741 if (ret)
742 return ret;
743
744
745
746
747
748
749
750
751
752
753
754
755
756 if (vdev->vdomain)
757 vdev->vdomain->nr_endpoints--;
758
759 req = (struct virtio_iommu_req_attach) {
760 .head.type = VIRTIO_IOMMU_T_ATTACH,
761 .domain = cpu_to_le32(vdomain->id),
762 };
763
764 if (vdomain->bypass)
765 req.flags |= cpu_to_le32(VIRTIO_IOMMU_ATTACH_F_BYPASS);
766
767 for (i = 0; i < fwspec->num_ids; i++) {
768 req.endpoint = cpu_to_le32(fwspec->ids[i]);
769
770 ret = viommu_send_req_sync(vdomain->viommu, &req, sizeof(req));
771 if (ret)
772 return ret;
773 }
774
775 if (!vdomain->nr_endpoints) {
776
777
778
779
780 ret = viommu_replay_mappings(vdomain);
781 if (ret)
782 return ret;
783 }
784
785 vdomain->nr_endpoints++;
786 vdev->vdomain = vdomain;
787
788 return 0;
789}
790
791static int viommu_map(struct iommu_domain *domain, unsigned long iova,
792 phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
793{
794 int ret;
795 u32 flags;
796 u64 end = iova + size - 1;
797 struct virtio_iommu_req_map map;
798 struct viommu_domain *vdomain = to_viommu_domain(domain);
799
800 flags = (prot & IOMMU_READ ? VIRTIO_IOMMU_MAP_F_READ : 0) |
801 (prot & IOMMU_WRITE ? VIRTIO_IOMMU_MAP_F_WRITE : 0) |
802 (prot & IOMMU_MMIO ? VIRTIO_IOMMU_MAP_F_MMIO : 0);
803
804 if (flags & ~vdomain->map_flags)
805 return -EINVAL;
806
807 ret = viommu_add_mapping(vdomain, iova, end, paddr, flags);
808 if (ret)
809 return ret;
810
811 map = (struct virtio_iommu_req_map) {
812 .head.type = VIRTIO_IOMMU_T_MAP,
813 .domain = cpu_to_le32(vdomain->id),
814 .virt_start = cpu_to_le64(iova),
815 .phys_start = cpu_to_le64(paddr),
816 .virt_end = cpu_to_le64(end),
817 .flags = cpu_to_le32(flags),
818 };
819
820 if (!vdomain->nr_endpoints)
821 return 0;
822
823 ret = viommu_send_req_sync(vdomain->viommu, &map, sizeof(map));
824 if (ret)
825 viommu_del_mappings(vdomain, iova, end);
826
827 return ret;
828}
829
830static size_t viommu_unmap(struct iommu_domain *domain, unsigned long iova,
831 size_t size, struct iommu_iotlb_gather *gather)
832{
833 int ret = 0;
834 size_t unmapped;
835 struct virtio_iommu_req_unmap unmap;
836 struct viommu_domain *vdomain = to_viommu_domain(domain);
837
838 unmapped = viommu_del_mappings(vdomain, iova, iova + size - 1);
839 if (unmapped < size)
840 return 0;
841
842
843 if (!vdomain->nr_endpoints)
844 return unmapped;
845
846 unmap = (struct virtio_iommu_req_unmap) {
847 .head.type = VIRTIO_IOMMU_T_UNMAP,
848 .domain = cpu_to_le32(vdomain->id),
849 .virt_start = cpu_to_le64(iova),
850 .virt_end = cpu_to_le64(iova + unmapped - 1),
851 };
852
853 ret = viommu_add_req(vdomain->viommu, &unmap, sizeof(unmap));
854 return ret ? 0 : unmapped;
855}
856
857static phys_addr_t viommu_iova_to_phys(struct iommu_domain *domain,
858 dma_addr_t iova)
859{
860 u64 paddr = 0;
861 unsigned long flags;
862 struct viommu_mapping *mapping;
863 struct interval_tree_node *node;
864 struct viommu_domain *vdomain = to_viommu_domain(domain);
865
866 spin_lock_irqsave(&vdomain->mappings_lock, flags);
867 node = interval_tree_iter_first(&vdomain->mappings, iova, iova);
868 if (node) {
869 mapping = container_of(node, struct viommu_mapping, iova);
870 paddr = mapping->paddr + (iova - mapping->iova.start);
871 }
872 spin_unlock_irqrestore(&vdomain->mappings_lock, flags);
873
874 return paddr;
875}
876
877static void viommu_iotlb_sync(struct iommu_domain *domain,
878 struct iommu_iotlb_gather *gather)
879{
880 struct viommu_domain *vdomain = to_viommu_domain(domain);
881
882 viommu_sync_req(vdomain->viommu);
883}
884
885static void viommu_get_resv_regions(struct device *dev, struct list_head *head)
886{
887 struct iommu_resv_region *entry, *new_entry, *msi = NULL;
888 struct viommu_endpoint *vdev = dev_iommu_priv_get(dev);
889 int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO;
890
891 list_for_each_entry(entry, &vdev->resv_regions, list) {
892 if (entry->type == IOMMU_RESV_MSI)
893 msi = entry;
894
895 new_entry = kmemdup(entry, sizeof(*entry), GFP_KERNEL);
896 if (!new_entry)
897 return;
898 list_add_tail(&new_entry->list, head);
899 }
900
901
902
903
904
905 if (!msi) {
906 msi = iommu_alloc_resv_region(MSI_IOVA_BASE, MSI_IOVA_LENGTH,
907 prot, IOMMU_RESV_SW_MSI);
908 if (!msi)
909 return;
910
911 list_add_tail(&msi->list, head);
912 }
913
914 iommu_dma_get_resv_regions(dev, head);
915}
916
917static struct iommu_ops viommu_ops;
918static struct virtio_driver virtio_iommu_drv;
919
920static int viommu_match_node(struct device *dev, const void *data)
921{
922 return dev->parent->fwnode == data;
923}
924
925static struct viommu_dev *viommu_get_by_fwnode(struct fwnode_handle *fwnode)
926{
927 struct device *dev = driver_find_device(&virtio_iommu_drv.driver, NULL,
928 fwnode, viommu_match_node);
929 put_device(dev);
930
931 return dev ? dev_to_virtio(dev)->priv : NULL;
932}
933
934static struct iommu_device *viommu_probe_device(struct device *dev)
935{
936 int ret;
937 struct viommu_endpoint *vdev;
938 struct viommu_dev *viommu = NULL;
939 struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
940
941 if (!fwspec || fwspec->ops != &viommu_ops)
942 return ERR_PTR(-ENODEV);
943
944 viommu = viommu_get_by_fwnode(fwspec->iommu_fwnode);
945 if (!viommu)
946 return ERR_PTR(-ENODEV);
947
948 vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
949 if (!vdev)
950 return ERR_PTR(-ENOMEM);
951
952 vdev->dev = dev;
953 vdev->viommu = viommu;
954 INIT_LIST_HEAD(&vdev->resv_regions);
955 dev_iommu_priv_set(dev, vdev);
956
957 if (viommu->probe_size) {
958
959 ret = viommu_probe_endpoint(viommu, dev);
960 if (ret)
961 goto err_free_dev;
962 }
963
964 return &viommu->iommu;
965
966err_free_dev:
967 generic_iommu_put_resv_regions(dev, &vdev->resv_regions);
968 kfree(vdev);
969
970 return ERR_PTR(ret);
971}
972
973static void viommu_probe_finalize(struct device *dev)
974{
975#ifndef CONFIG_ARCH_HAS_SETUP_DMA_OPS
976
977 set_dma_ops(dev, NULL);
978 iommu_setup_dma_ops(dev, 0, U64_MAX);
979#endif
980}
981
982static void viommu_release_device(struct device *dev)
983{
984 struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
985 struct viommu_endpoint *vdev;
986
987 if (!fwspec || fwspec->ops != &viommu_ops)
988 return;
989
990 vdev = dev_iommu_priv_get(dev);
991
992 generic_iommu_put_resv_regions(dev, &vdev->resv_regions);
993 kfree(vdev);
994}
995
996static struct iommu_group *viommu_device_group(struct device *dev)
997{
998 if (dev_is_pci(dev))
999 return pci_device_group(dev);
1000 else
1001 return generic_device_group(dev);
1002}
1003
1004static int viommu_of_xlate(struct device *dev, struct of_phandle_args *args)
1005{
1006 return iommu_fwspec_add_ids(dev, args->args, 1);
1007}
1008
1009static struct iommu_ops viommu_ops = {
1010 .domain_alloc = viommu_domain_alloc,
1011 .probe_device = viommu_probe_device,
1012 .probe_finalize = viommu_probe_finalize,
1013 .release_device = viommu_release_device,
1014 .device_group = viommu_device_group,
1015 .get_resv_regions = viommu_get_resv_regions,
1016 .put_resv_regions = generic_iommu_put_resv_regions,
1017 .of_xlate = viommu_of_xlate,
1018 .owner = THIS_MODULE,
1019 .default_domain_ops = &(const struct iommu_domain_ops) {
1020 .attach_dev = viommu_attach_dev,
1021 .map = viommu_map,
1022 .unmap = viommu_unmap,
1023 .iova_to_phys = viommu_iova_to_phys,
1024 .iotlb_sync = viommu_iotlb_sync,
1025 .free = viommu_domain_free,
1026 }
1027};
1028
1029static int viommu_init_vqs(struct viommu_dev *viommu)
1030{
1031 struct virtio_device *vdev = dev_to_virtio(viommu->dev);
1032 const char *names[] = { "request", "event" };
1033 vq_callback_t *callbacks[] = {
1034 NULL,
1035 viommu_event_handler,
1036 };
1037
1038 return virtio_find_vqs(vdev, VIOMMU_NR_VQS, viommu->vqs, callbacks,
1039 names, NULL);
1040}
1041
1042static int viommu_fill_evtq(struct viommu_dev *viommu)
1043{
1044 int i, ret;
1045 struct scatterlist sg[1];
1046 struct viommu_event *evts;
1047 struct virtqueue *vq = viommu->vqs[VIOMMU_EVENT_VQ];
1048 size_t nr_evts = vq->num_free;
1049
1050 viommu->evts = evts = devm_kmalloc_array(viommu->dev, nr_evts,
1051 sizeof(*evts), GFP_KERNEL);
1052 if (!evts)
1053 return -ENOMEM;
1054
1055 for (i = 0; i < nr_evts; i++) {
1056 sg_init_one(sg, &evts[i], sizeof(*evts));
1057 ret = virtqueue_add_inbuf(vq, sg, 1, &evts[i], GFP_KERNEL);
1058 if (ret)
1059 return ret;
1060 }
1061
1062 return 0;
1063}
1064
1065static int viommu_probe(struct virtio_device *vdev)
1066{
1067 struct device *parent_dev = vdev->dev.parent;
1068 struct viommu_dev *viommu = NULL;
1069 struct device *dev = &vdev->dev;
1070 u64 input_start = 0;
1071 u64 input_end = -1UL;
1072 int ret;
1073
1074 if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1) ||
1075 !virtio_has_feature(vdev, VIRTIO_IOMMU_F_MAP_UNMAP))
1076 return -ENODEV;
1077
1078 viommu = devm_kzalloc(dev, sizeof(*viommu), GFP_KERNEL);
1079 if (!viommu)
1080 return -ENOMEM;
1081
1082 spin_lock_init(&viommu->request_lock);
1083 ida_init(&viommu->domain_ids);
1084 viommu->dev = dev;
1085 viommu->vdev = vdev;
1086 INIT_LIST_HEAD(&viommu->requests);
1087
1088 ret = viommu_init_vqs(viommu);
1089 if (ret)
1090 return ret;
1091
1092 virtio_cread_le(vdev, struct virtio_iommu_config, page_size_mask,
1093 &viommu->pgsize_bitmap);
1094
1095 if (!viommu->pgsize_bitmap) {
1096 ret = -EINVAL;
1097 goto err_free_vqs;
1098 }
1099
1100 viommu->map_flags = VIRTIO_IOMMU_MAP_F_READ | VIRTIO_IOMMU_MAP_F_WRITE;
1101 viommu->last_domain = ~0U;
1102
1103
1104 virtio_cread_le_feature(vdev, VIRTIO_IOMMU_F_INPUT_RANGE,
1105 struct virtio_iommu_config, input_range.start,
1106 &input_start);
1107
1108 virtio_cread_le_feature(vdev, VIRTIO_IOMMU_F_INPUT_RANGE,
1109 struct virtio_iommu_config, input_range.end,
1110 &input_end);
1111
1112 virtio_cread_le_feature(vdev, VIRTIO_IOMMU_F_DOMAIN_RANGE,
1113 struct virtio_iommu_config, domain_range.start,
1114 &viommu->first_domain);
1115
1116 virtio_cread_le_feature(vdev, VIRTIO_IOMMU_F_DOMAIN_RANGE,
1117 struct virtio_iommu_config, domain_range.end,
1118 &viommu->last_domain);
1119
1120 virtio_cread_le_feature(vdev, VIRTIO_IOMMU_F_PROBE,
1121 struct virtio_iommu_config, probe_size,
1122 &viommu->probe_size);
1123
1124 viommu->geometry = (struct iommu_domain_geometry) {
1125 .aperture_start = input_start,
1126 .aperture_end = input_end,
1127 .force_aperture = true,
1128 };
1129
1130 if (virtio_has_feature(vdev, VIRTIO_IOMMU_F_MMIO))
1131 viommu->map_flags |= VIRTIO_IOMMU_MAP_F_MMIO;
1132
1133 viommu_ops.pgsize_bitmap = viommu->pgsize_bitmap;
1134
1135 virtio_device_ready(vdev);
1136
1137
1138 ret = viommu_fill_evtq(viommu);
1139 if (ret)
1140 goto err_free_vqs;
1141
1142 ret = iommu_device_sysfs_add(&viommu->iommu, dev, NULL, "%s",
1143 virtio_bus_name(vdev));
1144 if (ret)
1145 goto err_free_vqs;
1146
1147 iommu_device_register(&viommu->iommu, &viommu_ops, parent_dev);
1148
1149#ifdef CONFIG_PCI
1150 if (pci_bus_type.iommu_ops != &viommu_ops) {
1151 ret = bus_set_iommu(&pci_bus_type, &viommu_ops);
1152 if (ret)
1153 goto err_unregister;
1154 }
1155#endif
1156#ifdef CONFIG_ARM_AMBA
1157 if (amba_bustype.iommu_ops != &viommu_ops) {
1158 ret = bus_set_iommu(&amba_bustype, &viommu_ops);
1159 if (ret)
1160 goto err_unregister;
1161 }
1162#endif
1163 if (platform_bus_type.iommu_ops != &viommu_ops) {
1164 ret = bus_set_iommu(&platform_bus_type, &viommu_ops);
1165 if (ret)
1166 goto err_unregister;
1167 }
1168
1169 vdev->priv = viommu;
1170
1171 dev_info(dev, "input address: %u bits\n",
1172 order_base_2(viommu->geometry.aperture_end));
1173 dev_info(dev, "page mask: %#llx\n", viommu->pgsize_bitmap);
1174
1175 return 0;
1176
1177err_unregister:
1178 iommu_device_sysfs_remove(&viommu->iommu);
1179 iommu_device_unregister(&viommu->iommu);
1180err_free_vqs:
1181 vdev->config->del_vqs(vdev);
1182
1183 return ret;
1184}
1185
1186static void viommu_remove(struct virtio_device *vdev)
1187{
1188 struct viommu_dev *viommu = vdev->priv;
1189
1190 iommu_device_sysfs_remove(&viommu->iommu);
1191 iommu_device_unregister(&viommu->iommu);
1192
1193
1194 virtio_reset_device(vdev);
1195 vdev->config->del_vqs(vdev);
1196
1197 dev_info(&vdev->dev, "device removed\n");
1198}
1199
1200static void viommu_config_changed(struct virtio_device *vdev)
1201{
1202 dev_warn(&vdev->dev, "config changed\n");
1203}
1204
1205static unsigned int features[] = {
1206 VIRTIO_IOMMU_F_MAP_UNMAP,
1207 VIRTIO_IOMMU_F_INPUT_RANGE,
1208 VIRTIO_IOMMU_F_DOMAIN_RANGE,
1209 VIRTIO_IOMMU_F_PROBE,
1210 VIRTIO_IOMMU_F_MMIO,
1211 VIRTIO_IOMMU_F_BYPASS_CONFIG,
1212};
1213
1214static struct virtio_device_id id_table[] = {
1215 { VIRTIO_ID_IOMMU, VIRTIO_DEV_ANY_ID },
1216 { 0 },
1217};
1218MODULE_DEVICE_TABLE(virtio, id_table);
1219
1220static struct virtio_driver virtio_iommu_drv = {
1221 .driver.name = KBUILD_MODNAME,
1222 .driver.owner = THIS_MODULE,
1223 .id_table = id_table,
1224 .feature_table = features,
1225 .feature_table_size = ARRAY_SIZE(features),
1226 .probe = viommu_probe,
1227 .remove = viommu_remove,
1228 .config_changed = viommu_config_changed,
1229};
1230
1231module_virtio_driver(virtio_iommu_drv);
1232
1233MODULE_DESCRIPTION("Virtio IOMMU driver");
1234MODULE_AUTHOR("Jean-Philippe Brucker <jean-philippe.brucker@arm.com>");
1235MODULE_LICENSE("GPL v2");
1236