xref: /linux/drivers/gpu/drm/tegra/gem.c (revision 79997eda0d31bc68203c95ecb978773ee6ce7a1f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * NVIDIA Tegra DRM GEM helper functions
4  *
5  * Copyright (C) 2012 Sascha Hauer, Pengutronix
6  * Copyright (C) 2013-2015 NVIDIA CORPORATION, All rights reserved.
7  *
8  * Based on the GEM/CMA helpers
9  *
10  * Copyright (c) 2011 Samsung Electronics Co., Ltd.
11  */
12 
13 #include <linux/dma-buf.h>
14 #include <linux/iommu.h>
15 #include <linux/module.h>
16 #include <linux/vmalloc.h>
17 
18 #include <drm/drm_drv.h>
19 #include <drm/drm_prime.h>
20 #include <drm/tegra_drm.h>
21 
22 #include "drm.h"
23 #include "gem.h"
24 
25 MODULE_IMPORT_NS(DMA_BUF);
26 
27 static unsigned int sg_dma_count_chunks(struct scatterlist *sgl, unsigned int nents)
28 {
29 	dma_addr_t next = ~(dma_addr_t)0;
30 	unsigned int count = 0, i;
31 	struct scatterlist *s;
32 
33 	for_each_sg(sgl, s, nents, i) {
34 		/* sg_dma_address(s) is only valid for entries that have sg_dma_len(s) != 0. */
35 		if (!sg_dma_len(s))
36 			continue;
37 
38 		if (sg_dma_address(s) != next) {
39 			next = sg_dma_address(s) + sg_dma_len(s);
40 			count++;
41 		}
42 	}
43 
44 	return count;
45 }
46 
47 static inline unsigned int sgt_dma_count_chunks(struct sg_table *sgt)
48 {
49 	return sg_dma_count_chunks(sgt->sgl, sgt->nents);
50 }
51 
52 static void tegra_bo_put(struct host1x_bo *bo)
53 {
54 	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
55 
56 	drm_gem_object_put(&obj->gem);
57 }
58 
59 static struct host1x_bo_mapping *tegra_bo_pin(struct device *dev, struct host1x_bo *bo,
60 					      enum dma_data_direction direction)
61 {
62 	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
63 	struct drm_gem_object *gem = &obj->gem;
64 	struct host1x_bo_mapping *map;
65 	int err;
66 
67 	map = kzalloc(sizeof(*map), GFP_KERNEL);
68 	if (!map)
69 		return ERR_PTR(-ENOMEM);
70 
71 	kref_init(&map->ref);
72 	map->bo = host1x_bo_get(bo);
73 	map->direction = direction;
74 	map->dev = dev;
75 
76 	/*
77 	 * Imported buffers need special treatment to satisfy the semantics of DMA-BUF.
78 	 */
79 	if (gem->import_attach) {
80 		struct dma_buf *buf = gem->import_attach->dmabuf;
81 
82 		map->attach = dma_buf_attach(buf, dev);
83 		if (IS_ERR(map->attach)) {
84 			err = PTR_ERR(map->attach);
85 			goto free;
86 		}
87 
88 		map->sgt = dma_buf_map_attachment_unlocked(map->attach, direction);
89 		if (IS_ERR(map->sgt)) {
90 			dma_buf_detach(buf, map->attach);
91 			err = PTR_ERR(map->sgt);
92 			map->sgt = NULL;
93 			goto free;
94 		}
95 
96 		err = sgt_dma_count_chunks(map->sgt);
97 		map->size = gem->size;
98 
99 		goto out;
100 	}
101 
102 	/*
103 	 * If we don't have a mapping for this buffer yet, return an SG table
104 	 * so that host1x can do the mapping for us via the DMA API.
105 	 */
106 	map->sgt = kzalloc(sizeof(*map->sgt), GFP_KERNEL);
107 	if (!map->sgt) {
108 		err = -ENOMEM;
109 		goto free;
110 	}
111 
112 	if (obj->pages) {
113 		/*
114 		 * If the buffer object was allocated from the explicit IOMMU
115 		 * API code paths, construct an SG table from the pages.
116 		 */
117 		err = sg_alloc_table_from_pages(map->sgt, obj->pages, obj->num_pages, 0, gem->size,
118 						GFP_KERNEL);
119 		if (err < 0)
120 			goto free;
121 	} else {
122 		/*
123 		 * If the buffer object had no pages allocated and if it was
124 		 * not imported, it had to be allocated with the DMA API, so
125 		 * the DMA API helper can be used.
126 		 */
127 		err = dma_get_sgtable(dev, map->sgt, obj->vaddr, obj->iova, gem->size);
128 		if (err < 0)
129 			goto free;
130 	}
131 
132 	err = dma_map_sgtable(dev, map->sgt, direction, 0);
133 	if (err)
134 		goto free_sgt;
135 
136 out:
137 	/*
138 	 * If we've manually mapped the buffer object through the IOMMU, make sure to return the
139 	 * existing IOVA address of our mapping.
140 	 */
141 	if (!obj->mm) {
142 		map->phys = sg_dma_address(map->sgt->sgl);
143 		map->chunks = err;
144 	} else {
145 		map->phys = obj->iova;
146 		map->chunks = 1;
147 	}
148 
149 	map->size = gem->size;
150 
151 	return map;
152 
153 free_sgt:
154 	sg_free_table(map->sgt);
155 free:
156 	kfree(map->sgt);
157 	kfree(map);
158 	return ERR_PTR(err);
159 }
160 
161 static void tegra_bo_unpin(struct host1x_bo_mapping *map)
162 {
163 	if (map->attach) {
164 		dma_buf_unmap_attachment_unlocked(map->attach, map->sgt,
165 						  map->direction);
166 		dma_buf_detach(map->attach->dmabuf, map->attach);
167 	} else {
168 		dma_unmap_sgtable(map->dev, map->sgt, map->direction, 0);
169 		sg_free_table(map->sgt);
170 		kfree(map->sgt);
171 	}
172 
173 	host1x_bo_put(map->bo);
174 	kfree(map);
175 }
176 
177 static void *tegra_bo_mmap(struct host1x_bo *bo)
178 {
179 	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
180 	struct iosys_map map = { 0 };
181 	void *vaddr;
182 	int ret;
183 
184 	if (obj->vaddr)
185 		return obj->vaddr;
186 
187 	if (obj->gem.import_attach) {
188 		ret = dma_buf_vmap_unlocked(obj->gem.import_attach->dmabuf, &map);
189 		if (ret < 0)
190 			return ERR_PTR(ret);
191 
192 		return map.vaddr;
193 	}
194 
195 	vaddr = vmap(obj->pages, obj->num_pages, VM_MAP,
196 		     pgprot_writecombine(PAGE_KERNEL));
197 	if (!vaddr)
198 		return ERR_PTR(-ENOMEM);
199 
200 	return vaddr;
201 }
202 
203 static void tegra_bo_munmap(struct host1x_bo *bo, void *addr)
204 {
205 	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
206 	struct iosys_map map = IOSYS_MAP_INIT_VADDR(addr);
207 
208 	if (obj->vaddr)
209 		return;
210 
211 	if (obj->gem.import_attach)
212 		return dma_buf_vunmap_unlocked(obj->gem.import_attach->dmabuf, &map);
213 
214 	vunmap(addr);
215 }
216 
217 static struct host1x_bo *tegra_bo_get(struct host1x_bo *bo)
218 {
219 	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
220 
221 	drm_gem_object_get(&obj->gem);
222 
223 	return bo;
224 }
225 
226 static const struct host1x_bo_ops tegra_bo_ops = {
227 	.get = tegra_bo_get,
228 	.put = tegra_bo_put,
229 	.pin = tegra_bo_pin,
230 	.unpin = tegra_bo_unpin,
231 	.mmap = tegra_bo_mmap,
232 	.munmap = tegra_bo_munmap,
233 };
234 
235 static int tegra_bo_iommu_map(struct tegra_drm *tegra, struct tegra_bo *bo)
236 {
237 	int prot = IOMMU_READ | IOMMU_WRITE;
238 	int err;
239 
240 	if (bo->mm)
241 		return -EBUSY;
242 
243 	bo->mm = kzalloc(sizeof(*bo->mm), GFP_KERNEL);
244 	if (!bo->mm)
245 		return -ENOMEM;
246 
247 	mutex_lock(&tegra->mm_lock);
248 
249 	err = drm_mm_insert_node_generic(&tegra->mm,
250 					 bo->mm, bo->gem.size, PAGE_SIZE, 0, 0);
251 	if (err < 0) {
252 		dev_err(tegra->drm->dev, "out of I/O virtual memory: %d\n",
253 			err);
254 		goto unlock;
255 	}
256 
257 	bo->iova = bo->mm->start;
258 
259 	bo->size = iommu_map_sgtable(tegra->domain, bo->iova, bo->sgt, prot);
260 	if (!bo->size) {
261 		dev_err(tegra->drm->dev, "failed to map buffer\n");
262 		err = -ENOMEM;
263 		goto remove;
264 	}
265 
266 	mutex_unlock(&tegra->mm_lock);
267 
268 	return 0;
269 
270 remove:
271 	drm_mm_remove_node(bo->mm);
272 unlock:
273 	mutex_unlock(&tegra->mm_lock);
274 	kfree(bo->mm);
275 	return err;
276 }
277 
278 static int tegra_bo_iommu_unmap(struct tegra_drm *tegra, struct tegra_bo *bo)
279 {
280 	if (!bo->mm)
281 		return 0;
282 
283 	mutex_lock(&tegra->mm_lock);
284 	iommu_unmap(tegra->domain, bo->iova, bo->size);
285 	drm_mm_remove_node(bo->mm);
286 	mutex_unlock(&tegra->mm_lock);
287 
288 	kfree(bo->mm);
289 
290 	return 0;
291 }
292 
293 static const struct drm_gem_object_funcs tegra_gem_object_funcs = {
294 	.free = tegra_bo_free_object,
295 	.export = tegra_gem_prime_export,
296 	.vm_ops = &tegra_bo_vm_ops,
297 };
298 
299 static struct tegra_bo *tegra_bo_alloc_object(struct drm_device *drm,
300 					      size_t size)
301 {
302 	struct tegra_bo *bo;
303 	int err;
304 
305 	bo = kzalloc(sizeof(*bo), GFP_KERNEL);
306 	if (!bo)
307 		return ERR_PTR(-ENOMEM);
308 
309 	bo->gem.funcs = &tegra_gem_object_funcs;
310 
311 	host1x_bo_init(&bo->base, &tegra_bo_ops);
312 	size = round_up(size, PAGE_SIZE);
313 
314 	err = drm_gem_object_init(drm, &bo->gem, size);
315 	if (err < 0)
316 		goto free;
317 
318 	err = drm_gem_create_mmap_offset(&bo->gem);
319 	if (err < 0)
320 		goto release;
321 
322 	return bo;
323 
324 release:
325 	drm_gem_object_release(&bo->gem);
326 free:
327 	kfree(bo);
328 	return ERR_PTR(err);
329 }
330 
331 static void tegra_bo_free(struct drm_device *drm, struct tegra_bo *bo)
332 {
333 	if (bo->pages) {
334 		dma_unmap_sgtable(drm->dev, bo->sgt, DMA_FROM_DEVICE, 0);
335 		drm_gem_put_pages(&bo->gem, bo->pages, true, true);
336 		sg_free_table(bo->sgt);
337 		kfree(bo->sgt);
338 	} else if (bo->vaddr) {
339 		dma_free_wc(drm->dev, bo->gem.size, bo->vaddr, bo->iova);
340 	}
341 }
342 
343 static int tegra_bo_get_pages(struct drm_device *drm, struct tegra_bo *bo)
344 {
345 	int err;
346 
347 	bo->pages = drm_gem_get_pages(&bo->gem);
348 	if (IS_ERR(bo->pages))
349 		return PTR_ERR(bo->pages);
350 
351 	bo->num_pages = bo->gem.size >> PAGE_SHIFT;
352 
353 	bo->sgt = drm_prime_pages_to_sg(bo->gem.dev, bo->pages, bo->num_pages);
354 	if (IS_ERR(bo->sgt)) {
355 		err = PTR_ERR(bo->sgt);
356 		goto put_pages;
357 	}
358 
359 	err = dma_map_sgtable(drm->dev, bo->sgt, DMA_FROM_DEVICE, 0);
360 	if (err)
361 		goto free_sgt;
362 
363 	return 0;
364 
365 free_sgt:
366 	sg_free_table(bo->sgt);
367 	kfree(bo->sgt);
368 put_pages:
369 	drm_gem_put_pages(&bo->gem, bo->pages, false, false);
370 	return err;
371 }
372 
373 static int tegra_bo_alloc(struct drm_device *drm, struct tegra_bo *bo)
374 {
375 	struct tegra_drm *tegra = drm->dev_private;
376 	int err;
377 
378 	if (tegra->domain) {
379 		err = tegra_bo_get_pages(drm, bo);
380 		if (err < 0)
381 			return err;
382 
383 		err = tegra_bo_iommu_map(tegra, bo);
384 		if (err < 0) {
385 			tegra_bo_free(drm, bo);
386 			return err;
387 		}
388 	} else {
389 		size_t size = bo->gem.size;
390 
391 		bo->vaddr = dma_alloc_wc(drm->dev, size, &bo->iova,
392 					 GFP_KERNEL | __GFP_NOWARN);
393 		if (!bo->vaddr) {
394 			dev_err(drm->dev,
395 				"failed to allocate buffer of size %zu\n",
396 				size);
397 			return -ENOMEM;
398 		}
399 	}
400 
401 	return 0;
402 }
403 
404 struct tegra_bo *tegra_bo_create(struct drm_device *drm, size_t size,
405 				 unsigned long flags)
406 {
407 	struct tegra_bo *bo;
408 	int err;
409 
410 	bo = tegra_bo_alloc_object(drm, size);
411 	if (IS_ERR(bo))
412 		return bo;
413 
414 	err = tegra_bo_alloc(drm, bo);
415 	if (err < 0)
416 		goto release;
417 
418 	if (flags & DRM_TEGRA_GEM_CREATE_TILED)
419 		bo->tiling.mode = TEGRA_BO_TILING_MODE_TILED;
420 
421 	if (flags & DRM_TEGRA_GEM_CREATE_BOTTOM_UP)
422 		bo->flags |= TEGRA_BO_BOTTOM_UP;
423 
424 	return bo;
425 
426 release:
427 	drm_gem_object_release(&bo->gem);
428 	kfree(bo);
429 	return ERR_PTR(err);
430 }
431 
432 struct tegra_bo *tegra_bo_create_with_handle(struct drm_file *file,
433 					     struct drm_device *drm,
434 					     size_t size,
435 					     unsigned long flags,
436 					     u32 *handle)
437 {
438 	struct tegra_bo *bo;
439 	int err;
440 
441 	bo = tegra_bo_create(drm, size, flags);
442 	if (IS_ERR(bo))
443 		return bo;
444 
445 	err = drm_gem_handle_create(file, &bo->gem, handle);
446 	if (err) {
447 		tegra_bo_free_object(&bo->gem);
448 		return ERR_PTR(err);
449 	}
450 
451 	drm_gem_object_put(&bo->gem);
452 
453 	return bo;
454 }
455 
456 static struct tegra_bo *tegra_bo_import(struct drm_device *drm,
457 					struct dma_buf *buf)
458 {
459 	struct tegra_drm *tegra = drm->dev_private;
460 	struct dma_buf_attachment *attach;
461 	struct tegra_bo *bo;
462 	int err;
463 
464 	bo = tegra_bo_alloc_object(drm, buf->size);
465 	if (IS_ERR(bo))
466 		return bo;
467 
468 	attach = dma_buf_attach(buf, drm->dev);
469 	if (IS_ERR(attach)) {
470 		err = PTR_ERR(attach);
471 		goto free;
472 	}
473 
474 	get_dma_buf(buf);
475 
476 	bo->sgt = dma_buf_map_attachment_unlocked(attach, DMA_TO_DEVICE);
477 	if (IS_ERR(bo->sgt)) {
478 		err = PTR_ERR(bo->sgt);
479 		goto detach;
480 	}
481 
482 	if (tegra->domain) {
483 		err = tegra_bo_iommu_map(tegra, bo);
484 		if (err < 0)
485 			goto detach;
486 	}
487 
488 	bo->gem.import_attach = attach;
489 
490 	return bo;
491 
492 detach:
493 	if (!IS_ERR_OR_NULL(bo->sgt))
494 		dma_buf_unmap_attachment_unlocked(attach, bo->sgt, DMA_TO_DEVICE);
495 
496 	dma_buf_detach(buf, attach);
497 	dma_buf_put(buf);
498 free:
499 	drm_gem_object_release(&bo->gem);
500 	kfree(bo);
501 	return ERR_PTR(err);
502 }
503 
504 void tegra_bo_free_object(struct drm_gem_object *gem)
505 {
506 	struct tegra_drm *tegra = gem->dev->dev_private;
507 	struct host1x_bo_mapping *mapping, *tmp;
508 	struct tegra_bo *bo = to_tegra_bo(gem);
509 
510 	/* remove all mappings of this buffer object from any caches */
511 	list_for_each_entry_safe(mapping, tmp, &bo->base.mappings, list) {
512 		if (mapping->cache)
513 			host1x_bo_unpin(mapping);
514 		else
515 			dev_err(gem->dev->dev, "mapping %p stale for device %s\n", mapping,
516 				dev_name(mapping->dev));
517 	}
518 
519 	if (tegra->domain)
520 		tegra_bo_iommu_unmap(tegra, bo);
521 
522 	if (gem->import_attach) {
523 		dma_buf_unmap_attachment_unlocked(gem->import_attach, bo->sgt,
524 						  DMA_TO_DEVICE);
525 		drm_prime_gem_destroy(gem, NULL);
526 	} else {
527 		tegra_bo_free(gem->dev, bo);
528 	}
529 
530 	drm_gem_object_release(gem);
531 	kfree(bo);
532 }
533 
534 int tegra_bo_dumb_create(struct drm_file *file, struct drm_device *drm,
535 			 struct drm_mode_create_dumb *args)
536 {
537 	unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
538 	struct tegra_drm *tegra = drm->dev_private;
539 	struct tegra_bo *bo;
540 
541 	args->pitch = round_up(min_pitch, tegra->pitch_align);
542 	args->size = args->pitch * args->height;
543 
544 	bo = tegra_bo_create_with_handle(file, drm, args->size, 0,
545 					 &args->handle);
546 	if (IS_ERR(bo))
547 		return PTR_ERR(bo);
548 
549 	return 0;
550 }
551 
552 static vm_fault_t tegra_bo_fault(struct vm_fault *vmf)
553 {
554 	struct vm_area_struct *vma = vmf->vma;
555 	struct drm_gem_object *gem = vma->vm_private_data;
556 	struct tegra_bo *bo = to_tegra_bo(gem);
557 	struct page *page;
558 	pgoff_t offset;
559 
560 	if (!bo->pages)
561 		return VM_FAULT_SIGBUS;
562 
563 	offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
564 	page = bo->pages[offset];
565 
566 	return vmf_insert_page(vma, vmf->address, page);
567 }
568 
569 const struct vm_operations_struct tegra_bo_vm_ops = {
570 	.fault = tegra_bo_fault,
571 	.open = drm_gem_vm_open,
572 	.close = drm_gem_vm_close,
573 };
574 
575 int __tegra_gem_mmap(struct drm_gem_object *gem, struct vm_area_struct *vma)
576 {
577 	struct tegra_bo *bo = to_tegra_bo(gem);
578 
579 	if (!bo->pages) {
580 		unsigned long vm_pgoff = vma->vm_pgoff;
581 		int err;
582 
583 		/*
584 		 * Clear the VM_PFNMAP flag that was set by drm_gem_mmap(),
585 		 * and set the vm_pgoff (used as a fake buffer offset by DRM)
586 		 * to 0 as we want to map the whole buffer.
587 		 */
588 		vm_flags_clear(vma, VM_PFNMAP);
589 		vma->vm_pgoff = 0;
590 
591 		err = dma_mmap_wc(gem->dev->dev, vma, bo->vaddr, bo->iova,
592 				  gem->size);
593 		if (err < 0) {
594 			drm_gem_vm_close(vma);
595 			return err;
596 		}
597 
598 		vma->vm_pgoff = vm_pgoff;
599 	} else {
600 		pgprot_t prot = vm_get_page_prot(vma->vm_flags);
601 
602 		vm_flags_mod(vma, VM_MIXEDMAP, VM_PFNMAP);
603 
604 		vma->vm_page_prot = pgprot_writecombine(prot);
605 	}
606 
607 	return 0;
608 }
609 
610 int tegra_drm_mmap(struct file *file, struct vm_area_struct *vma)
611 {
612 	struct drm_gem_object *gem;
613 	int err;
614 
615 	err = drm_gem_mmap(file, vma);
616 	if (err < 0)
617 		return err;
618 
619 	gem = vma->vm_private_data;
620 
621 	return __tegra_gem_mmap(gem, vma);
622 }
623 
624 static struct sg_table *
625 tegra_gem_prime_map_dma_buf(struct dma_buf_attachment *attach,
626 			    enum dma_data_direction dir)
627 {
628 	struct drm_gem_object *gem = attach->dmabuf->priv;
629 	struct tegra_bo *bo = to_tegra_bo(gem);
630 	struct sg_table *sgt;
631 
632 	sgt = kmalloc(sizeof(*sgt), GFP_KERNEL);
633 	if (!sgt)
634 		return NULL;
635 
636 	if (bo->pages) {
637 		if (sg_alloc_table_from_pages(sgt, bo->pages, bo->num_pages,
638 					      0, gem->size, GFP_KERNEL) < 0)
639 			goto free;
640 	} else {
641 		if (dma_get_sgtable(attach->dev, sgt, bo->vaddr, bo->iova,
642 				    gem->size) < 0)
643 			goto free;
644 	}
645 
646 	if (dma_map_sgtable(attach->dev, sgt, dir, 0))
647 		goto free;
648 
649 	return sgt;
650 
651 free:
652 	sg_free_table(sgt);
653 	kfree(sgt);
654 	return NULL;
655 }
656 
657 static void tegra_gem_prime_unmap_dma_buf(struct dma_buf_attachment *attach,
658 					  struct sg_table *sgt,
659 					  enum dma_data_direction dir)
660 {
661 	struct drm_gem_object *gem = attach->dmabuf->priv;
662 	struct tegra_bo *bo = to_tegra_bo(gem);
663 
664 	if (bo->pages)
665 		dma_unmap_sgtable(attach->dev, sgt, dir, 0);
666 
667 	sg_free_table(sgt);
668 	kfree(sgt);
669 }
670 
671 static void tegra_gem_prime_release(struct dma_buf *buf)
672 {
673 	drm_gem_dmabuf_release(buf);
674 }
675 
676 static int tegra_gem_prime_begin_cpu_access(struct dma_buf *buf,
677 					    enum dma_data_direction direction)
678 {
679 	struct drm_gem_object *gem = buf->priv;
680 	struct tegra_bo *bo = to_tegra_bo(gem);
681 	struct drm_device *drm = gem->dev;
682 
683 	if (bo->pages)
684 		dma_sync_sgtable_for_cpu(drm->dev, bo->sgt, DMA_FROM_DEVICE);
685 
686 	return 0;
687 }
688 
689 static int tegra_gem_prime_end_cpu_access(struct dma_buf *buf,
690 					  enum dma_data_direction direction)
691 {
692 	struct drm_gem_object *gem = buf->priv;
693 	struct tegra_bo *bo = to_tegra_bo(gem);
694 	struct drm_device *drm = gem->dev;
695 
696 	if (bo->pages)
697 		dma_sync_sgtable_for_device(drm->dev, bo->sgt, DMA_TO_DEVICE);
698 
699 	return 0;
700 }
701 
702 static int tegra_gem_prime_mmap(struct dma_buf *buf, struct vm_area_struct *vma)
703 {
704 	struct drm_gem_object *gem = buf->priv;
705 	int err;
706 
707 	err = drm_gem_mmap_obj(gem, gem->size, vma);
708 	if (err < 0)
709 		return err;
710 
711 	return __tegra_gem_mmap(gem, vma);
712 }
713 
714 static int tegra_gem_prime_vmap(struct dma_buf *buf, struct iosys_map *map)
715 {
716 	struct drm_gem_object *gem = buf->priv;
717 	struct tegra_bo *bo = to_tegra_bo(gem);
718 	void *vaddr;
719 
720 	vaddr = tegra_bo_mmap(&bo->base);
721 	if (IS_ERR(vaddr))
722 		return PTR_ERR(vaddr);
723 
724 	iosys_map_set_vaddr(map, vaddr);
725 
726 	return 0;
727 }
728 
729 static void tegra_gem_prime_vunmap(struct dma_buf *buf, struct iosys_map *map)
730 {
731 	struct drm_gem_object *gem = buf->priv;
732 	struct tegra_bo *bo = to_tegra_bo(gem);
733 
734 	tegra_bo_munmap(&bo->base, map->vaddr);
735 }
736 
737 static const struct dma_buf_ops tegra_gem_prime_dmabuf_ops = {
738 	.map_dma_buf = tegra_gem_prime_map_dma_buf,
739 	.unmap_dma_buf = tegra_gem_prime_unmap_dma_buf,
740 	.release = tegra_gem_prime_release,
741 	.begin_cpu_access = tegra_gem_prime_begin_cpu_access,
742 	.end_cpu_access = tegra_gem_prime_end_cpu_access,
743 	.mmap = tegra_gem_prime_mmap,
744 	.vmap = tegra_gem_prime_vmap,
745 	.vunmap = tegra_gem_prime_vunmap,
746 };
747 
748 struct dma_buf *tegra_gem_prime_export(struct drm_gem_object *gem,
749 				       int flags)
750 {
751 	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
752 
753 	exp_info.exp_name = KBUILD_MODNAME;
754 	exp_info.owner = gem->dev->driver->fops->owner;
755 	exp_info.ops = &tegra_gem_prime_dmabuf_ops;
756 	exp_info.size = gem->size;
757 	exp_info.flags = flags;
758 	exp_info.priv = gem;
759 
760 	return drm_gem_dmabuf_export(gem->dev, &exp_info);
761 }
762 
763 struct drm_gem_object *tegra_gem_prime_import(struct drm_device *drm,
764 					      struct dma_buf *buf)
765 {
766 	struct tegra_bo *bo;
767 
768 	if (buf->ops == &tegra_gem_prime_dmabuf_ops) {
769 		struct drm_gem_object *gem = buf->priv;
770 
771 		if (gem->dev == drm) {
772 			drm_gem_object_get(gem);
773 			return gem;
774 		}
775 	}
776 
777 	bo = tegra_bo_import(drm, buf);
778 	if (IS_ERR(bo))
779 		return ERR_CAST(bo);
780 
781 	return &bo->gem;
782 }
783 
784 struct host1x_bo *tegra_gem_lookup(struct drm_file *file, u32 handle)
785 {
786 	struct drm_gem_object *gem;
787 	struct tegra_bo *bo;
788 
789 	gem = drm_gem_object_lookup(file, handle);
790 	if (!gem)
791 		return NULL;
792 
793 	bo = to_tegra_bo(gem);
794 	return &bo->base;
795 }
796