xref: /linux/drivers/gpu/drm/tegra/gem.c (revision d639d9fa162aadec1ae9980c4dcf6e50bd2f8290)
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_dumb_buffers.h>
20 #include <drm/drm_prime.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_obj(*map);
68 	if (!map)
69 		return ERR_PTR(-ENOMEM);
70 
71 	kref_init(&map->ref);
72 	map->bo = 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 (obj->dma_buf) {
80 		struct dma_buf *buf = obj->dma_buf;
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_obj(*map->sgt);
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 	kfree(map);
174 }
175 
176 static void *tegra_bo_mmap(struct host1x_bo *bo)
177 {
178 	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
179 	struct iosys_map map = { 0 };
180 	void *vaddr;
181 	int ret;
182 
183 	if (obj->vaddr)
184 		return obj->vaddr;
185 
186 	if (obj->dma_buf) {
187 		ret = dma_buf_vmap_unlocked(obj->dma_buf, &map);
188 		if (ret < 0)
189 			return ERR_PTR(ret);
190 
191 		return map.vaddr;
192 	}
193 
194 	vaddr = vmap(obj->pages, obj->num_pages, VM_MAP,
195 		     pgprot_writecombine(PAGE_KERNEL));
196 	if (!vaddr)
197 		return ERR_PTR(-ENOMEM);
198 
199 	return vaddr;
200 }
201 
202 static void tegra_bo_munmap(struct host1x_bo *bo, void *addr)
203 {
204 	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
205 	struct iosys_map map = IOSYS_MAP_INIT_VADDR(addr);
206 
207 	if (obj->vaddr)
208 		return;
209 
210 	if (obj->dma_buf)
211 		return dma_buf_vunmap_unlocked(obj->dma_buf, &map);
212 
213 	vunmap(addr);
214 }
215 
216 static struct host1x_bo *tegra_bo_get(struct host1x_bo *bo)
217 {
218 	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
219 
220 	drm_gem_object_get(&obj->gem);
221 
222 	return bo;
223 }
224 
225 static const struct host1x_bo_ops tegra_bo_ops = {
226 	.get = tegra_bo_get,
227 	.put = tegra_bo_put,
228 	.pin = tegra_bo_pin,
229 	.unpin = tegra_bo_unpin,
230 	.mmap = tegra_bo_mmap,
231 	.munmap = tegra_bo_munmap,
232 };
233 
234 static int tegra_bo_iommu_map(struct tegra_drm *tegra, struct tegra_bo *bo)
235 {
236 	int prot = IOMMU_READ | IOMMU_WRITE;
237 	ssize_t size;
238 	int err;
239 
240 	if (bo->mm)
241 		return -EBUSY;
242 
243 	bo->mm = kzalloc_obj(*bo->mm);
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 	size = iommu_map_sgtable(tegra->domain, bo->iova, bo->sgt, prot);
260 	if (size < 0) {
261 		dev_err(tegra->drm->dev, "failed to map buffer\n");
262 		err = size;
263 		goto remove;
264 	}
265 
266 	bo->size = size;
267 
268 	mutex_unlock(&tegra->mm_lock);
269 
270 	return 0;
271 
272 remove:
273 	drm_mm_remove_node(bo->mm);
274 unlock:
275 	mutex_unlock(&tegra->mm_lock);
276 	kfree(bo->mm);
277 	return err;
278 }
279 
280 static int tegra_bo_iommu_unmap(struct tegra_drm *tegra, struct tegra_bo *bo)
281 {
282 	if (!bo->mm)
283 		return 0;
284 
285 	mutex_lock(&tegra->mm_lock);
286 	iommu_unmap(tegra->domain, bo->iova, bo->size);
287 	drm_mm_remove_node(bo->mm);
288 	mutex_unlock(&tegra->mm_lock);
289 
290 	kfree(bo->mm);
291 
292 	return 0;
293 }
294 
295 static const struct drm_gem_object_funcs tegra_gem_object_funcs = {
296 	.free = tegra_bo_free_object,
297 	.export = tegra_gem_prime_export,
298 	.vm_ops = &tegra_bo_vm_ops,
299 };
300 
301 static struct tegra_bo *tegra_bo_alloc_object(struct drm_device *drm,
302 					      size_t size)
303 {
304 	struct tegra_bo *bo;
305 	int err;
306 
307 	bo = kzalloc_obj(*bo);
308 	if (!bo)
309 		return ERR_PTR(-ENOMEM);
310 
311 	bo->gem.funcs = &tegra_gem_object_funcs;
312 
313 	host1x_bo_init(&bo->base, &tegra_bo_ops);
314 	size = round_up(size, PAGE_SIZE);
315 
316 	err = drm_gem_object_init(drm, &bo->gem, size);
317 	if (err < 0)
318 		goto free;
319 
320 	err = drm_gem_create_mmap_offset(&bo->gem);
321 	if (err < 0)
322 		goto release;
323 
324 	return bo;
325 
326 release:
327 	drm_gem_object_release(&bo->gem);
328 free:
329 	kfree(bo);
330 	return ERR_PTR(err);
331 }
332 
333 static void tegra_bo_free(struct drm_device *drm, struct tegra_bo *bo)
334 {
335 	if (bo->pages) {
336 		dma_unmap_sgtable(drm->dev, bo->sgt, DMA_FROM_DEVICE, 0);
337 		drm_gem_put_pages(&bo->gem, bo->pages, true, true);
338 		sg_free_table(bo->sgt);
339 		kfree(bo->sgt);
340 	} else if (bo->vaddr) {
341 		dma_free_wc(drm->dev, bo->gem.size, bo->vaddr, bo->iova);
342 	}
343 }
344 
345 static int tegra_bo_get_pages(struct drm_device *drm, struct tegra_bo *bo)
346 {
347 	int err;
348 
349 	bo->pages = drm_gem_get_pages(&bo->gem);
350 	if (IS_ERR(bo->pages))
351 		return PTR_ERR(bo->pages);
352 
353 	bo->num_pages = bo->gem.size >> PAGE_SHIFT;
354 
355 	bo->sgt = drm_prime_pages_to_sg(bo->gem.dev, bo->pages, bo->num_pages);
356 	if (IS_ERR(bo->sgt)) {
357 		err = PTR_ERR(bo->sgt);
358 		goto put_pages;
359 	}
360 
361 	err = dma_map_sgtable(drm->dev, bo->sgt, DMA_FROM_DEVICE, 0);
362 	if (err)
363 		goto free_sgt;
364 
365 	return 0;
366 
367 free_sgt:
368 	sg_free_table(bo->sgt);
369 	kfree(bo->sgt);
370 put_pages:
371 	drm_gem_put_pages(&bo->gem, bo->pages, false, false);
372 	return err;
373 }
374 
375 static int tegra_bo_alloc(struct drm_device *drm, struct tegra_bo *bo)
376 {
377 	struct tegra_drm *tegra = drm->dev_private;
378 	int err;
379 
380 	if (tegra->domain) {
381 		err = tegra_bo_get_pages(drm, bo);
382 		if (err < 0)
383 			return err;
384 
385 		err = tegra_bo_iommu_map(tegra, bo);
386 		if (err < 0) {
387 			tegra_bo_free(drm, bo);
388 			return err;
389 		}
390 	} else {
391 		size_t size = bo->gem.size;
392 
393 		bo->vaddr = dma_alloc_wc(drm->dev, size, &bo->iova,
394 					 GFP_KERNEL | __GFP_NOWARN);
395 		if (!bo->vaddr) {
396 			dev_err(drm->dev,
397 				"failed to allocate buffer of size %zu\n",
398 				size);
399 			return -ENOMEM;
400 		}
401 	}
402 
403 	return 0;
404 }
405 
406 struct tegra_bo *tegra_bo_create(struct drm_device *drm, size_t size,
407 				 unsigned long flags)
408 {
409 	struct tegra_bo *bo;
410 	int err;
411 
412 	bo = tegra_bo_alloc_object(drm, size);
413 	if (IS_ERR(bo))
414 		return bo;
415 
416 	err = tegra_bo_alloc(drm, bo);
417 	if (err < 0)
418 		goto release;
419 
420 	if (flags & DRM_TEGRA_GEM_CREATE_TILED)
421 		bo->tiling.mode = TEGRA_BO_TILING_MODE_TILED;
422 
423 	if (flags & DRM_TEGRA_GEM_CREATE_BOTTOM_UP)
424 		bo->flags |= TEGRA_BO_BOTTOM_UP;
425 
426 	return bo;
427 
428 release:
429 	drm_gem_object_release(&bo->gem);
430 	kfree(bo);
431 	return ERR_PTR(err);
432 }
433 
434 struct tegra_bo *tegra_bo_create_with_handle(struct drm_file *file,
435 					     struct drm_device *drm,
436 					     size_t size,
437 					     unsigned long flags,
438 					     u32 *handle)
439 {
440 	struct tegra_bo *bo;
441 	int err;
442 
443 	bo = tegra_bo_create(drm, size, flags);
444 	if (IS_ERR(bo))
445 		return bo;
446 
447 	err = drm_gem_handle_create(file, &bo->gem, handle);
448 	if (err) {
449 		tegra_bo_free_object(&bo->gem);
450 		return ERR_PTR(err);
451 	}
452 
453 	drm_gem_object_put(&bo->gem);
454 
455 	return bo;
456 }
457 
458 static struct tegra_bo *tegra_bo_import(struct drm_device *drm,
459 					struct dma_buf *buf)
460 {
461 	struct tegra_drm *tegra = drm->dev_private;
462 	struct dma_buf_attachment *attach;
463 	struct tegra_bo *bo;
464 	int err;
465 
466 	bo = tegra_bo_alloc_object(drm, buf->size);
467 	if (IS_ERR(bo))
468 		return bo;
469 
470 	/*
471 	 * If we need to use IOMMU API to map the dma-buf into the internally managed
472 	 * domain, map it first to the DRM device to get an sgt.
473 	 */
474 	if (tegra->domain) {
475 		attach = dma_buf_attach(buf, drm->dev);
476 		if (IS_ERR(attach)) {
477 			err = PTR_ERR(attach);
478 			goto free;
479 		}
480 
481 		bo->sgt = dma_buf_map_attachment_unlocked(attach, DMA_TO_DEVICE);
482 		if (IS_ERR(bo->sgt)) {
483 			err = PTR_ERR(bo->sgt);
484 			goto detach;
485 		}
486 
487 		err = tegra_bo_iommu_map(tegra, bo);
488 		if (err < 0)
489 			goto detach;
490 
491 		bo->gem.import_attach = attach;
492 	}
493 
494 	get_dma_buf(buf);
495 	bo->dma_buf = buf;
496 
497 	return bo;
498 
499 detach:
500 	if (!IS_ERR_OR_NULL(bo->sgt))
501 		dma_buf_unmap_attachment_unlocked(attach, bo->sgt, DMA_TO_DEVICE);
502 
503 	dma_buf_detach(buf, attach);
504 	dma_buf_put(buf);
505 free:
506 	drm_gem_object_release(&bo->gem);
507 	kfree(bo);
508 	return ERR_PTR(err);
509 }
510 
511 void tegra_bo_free_object(struct drm_gem_object *gem)
512 {
513 	struct tegra_drm *tegra = gem->dev->dev_private;
514 	struct tegra_bo *bo = to_tegra_bo(gem);
515 
516 	host1x_bo_clear_cached_mappings(&bo->base);
517 
518 	if (tegra->domain) {
519 		tegra_bo_iommu_unmap(tegra, bo);
520 
521 		if (drm_gem_is_imported(gem)) {
522 			dma_buf_unmap_attachment_unlocked(gem->import_attach, bo->sgt,
523 							  DMA_TO_DEVICE);
524 			dma_buf_detach(gem->import_attach->dmabuf, gem->import_attach);
525 		}
526 	}
527 
528 	tegra_bo_free(gem->dev, bo);
529 
530 	if (bo->dma_buf)
531 		dma_buf_put(bo->dma_buf);
532 
533 	drm_gem_object_release(gem);
534 	kfree(bo);
535 }
536 
537 int tegra_bo_dumb_create(struct drm_file *file, struct drm_device *drm,
538 			 struct drm_mode_create_dumb *args)
539 {
540 	struct tegra_drm *tegra = drm->dev_private;
541 	struct tegra_bo *bo;
542 	int ret;
543 
544 	ret = drm_mode_size_dumb(drm, args, tegra->pitch_align, 0);
545 	if (ret)
546 		return ret;
547 
548 	bo = tegra_bo_create_with_handle(file, drm, args->size, 0,
549 					 &args->handle);
550 	if (IS_ERR(bo))
551 		return PTR_ERR(bo);
552 
553 	return 0;
554 }
555 
556 static vm_fault_t tegra_bo_fault(struct vm_fault *vmf)
557 {
558 	struct vm_area_struct *vma = vmf->vma;
559 	struct drm_gem_object *gem = vma->vm_private_data;
560 	struct tegra_bo *bo = to_tegra_bo(gem);
561 	struct page *page;
562 	pgoff_t offset;
563 
564 	if (!bo->pages)
565 		return VM_FAULT_SIGBUS;
566 
567 	offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
568 	page = bo->pages[offset];
569 
570 	return vmf_insert_page(vma, vmf->address, page);
571 }
572 
573 const struct vm_operations_struct tegra_bo_vm_ops = {
574 	.fault = tegra_bo_fault,
575 	.open = drm_gem_vm_open,
576 	.close = drm_gem_vm_close,
577 };
578 
579 int __tegra_gem_mmap(struct drm_gem_object *gem, struct vm_area_struct *vma)
580 {
581 	struct tegra_bo *bo = to_tegra_bo(gem);
582 
583 	if (!bo->pages) {
584 		unsigned long vm_pgoff = vma->vm_pgoff;
585 		int err;
586 
587 		/*
588 		 * Clear the VM_PFNMAP flag that was set by drm_gem_mmap(),
589 		 * and set the vm_pgoff (used as a fake buffer offset by DRM)
590 		 * to 0 as we want to map the whole buffer.
591 		 */
592 		vm_flags_clear(vma, VM_PFNMAP);
593 		vma->vm_pgoff = 0;
594 
595 		err = dma_mmap_wc(gem->dev->dev, vma, bo->vaddr, bo->iova,
596 				  gem->size);
597 		if (err < 0) {
598 			drm_gem_vm_close(vma);
599 			return err;
600 		}
601 
602 		vma->vm_pgoff = vm_pgoff;
603 	} else {
604 		pgprot_t prot = vm_get_page_prot(vma->vm_flags);
605 
606 		vm_flags_mod(vma, VM_MIXEDMAP, VM_PFNMAP);
607 
608 		vma->vm_page_prot = pgprot_writecombine(prot);
609 	}
610 
611 	return 0;
612 }
613 
614 int tegra_drm_mmap(struct file *file, struct vm_area_struct *vma)
615 {
616 	struct drm_gem_object *gem;
617 	int err;
618 
619 	err = drm_gem_mmap(file, vma);
620 	if (err < 0)
621 		return err;
622 
623 	gem = vma->vm_private_data;
624 
625 	return __tegra_gem_mmap(gem, vma);
626 }
627 
628 static struct sg_table *
629 tegra_gem_prime_map_dma_buf(struct dma_buf_attachment *attach,
630 			    enum dma_data_direction dir)
631 {
632 	struct drm_gem_object *gem = attach->dmabuf->priv;
633 	struct tegra_bo *bo = to_tegra_bo(gem);
634 	struct sg_table *sgt;
635 
636 	sgt = kmalloc_obj(*sgt);
637 	if (!sgt)
638 		return NULL;
639 
640 	if (bo->pages) {
641 		if (sg_alloc_table_from_pages(sgt, bo->pages, bo->num_pages,
642 					      0, gem->size, GFP_KERNEL) < 0)
643 			goto free;
644 	} else {
645 		if (dma_get_sgtable(attach->dev, sgt, bo->vaddr, bo->iova,
646 				    gem->size) < 0)
647 			goto free;
648 	}
649 
650 	if (dma_map_sgtable(attach->dev, sgt, dir, 0))
651 		goto free;
652 
653 	return sgt;
654 
655 free:
656 	sg_free_table(sgt);
657 	kfree(sgt);
658 	return NULL;
659 }
660 
661 static void tegra_gem_prime_unmap_dma_buf(struct dma_buf_attachment *attach,
662 					  struct sg_table *sgt,
663 					  enum dma_data_direction dir)
664 {
665 	struct drm_gem_object *gem = attach->dmabuf->priv;
666 	struct tegra_bo *bo = to_tegra_bo(gem);
667 
668 	if (bo->pages)
669 		dma_unmap_sgtable(attach->dev, sgt, dir, 0);
670 
671 	sg_free_table(sgt);
672 	kfree(sgt);
673 }
674 
675 static void tegra_gem_prime_release(struct dma_buf *buf)
676 {
677 	drm_gem_dmabuf_release(buf);
678 }
679 
680 static int tegra_gem_prime_begin_cpu_access(struct dma_buf *buf,
681 					    enum dma_data_direction direction)
682 {
683 	struct drm_gem_object *gem = buf->priv;
684 	struct tegra_bo *bo = to_tegra_bo(gem);
685 	struct drm_device *drm = gem->dev;
686 
687 	if (bo->pages)
688 		dma_sync_sgtable_for_cpu(drm->dev, bo->sgt, DMA_FROM_DEVICE);
689 
690 	return 0;
691 }
692 
693 static int tegra_gem_prime_end_cpu_access(struct dma_buf *buf,
694 					  enum dma_data_direction direction)
695 {
696 	struct drm_gem_object *gem = buf->priv;
697 	struct tegra_bo *bo = to_tegra_bo(gem);
698 	struct drm_device *drm = gem->dev;
699 
700 	if (bo->pages)
701 		dma_sync_sgtable_for_device(drm->dev, bo->sgt, DMA_TO_DEVICE);
702 
703 	return 0;
704 }
705 
706 static int tegra_gem_prime_mmap(struct dma_buf *buf, struct vm_area_struct *vma)
707 {
708 	struct drm_gem_object *gem = buf->priv;
709 	int err;
710 
711 	err = drm_gem_mmap_obj(gem, gem->size, vma);
712 	if (err < 0)
713 		return err;
714 
715 	return __tegra_gem_mmap(gem, vma);
716 }
717 
718 static int tegra_gem_prime_vmap(struct dma_buf *buf, struct iosys_map *map)
719 {
720 	struct drm_gem_object *gem = buf->priv;
721 	struct tegra_bo *bo = to_tegra_bo(gem);
722 	void *vaddr;
723 
724 	vaddr = tegra_bo_mmap(&bo->base);
725 	if (IS_ERR(vaddr))
726 		return PTR_ERR(vaddr);
727 
728 	iosys_map_set_vaddr(map, vaddr);
729 
730 	return 0;
731 }
732 
733 static void tegra_gem_prime_vunmap(struct dma_buf *buf, struct iosys_map *map)
734 {
735 	struct drm_gem_object *gem = buf->priv;
736 	struct tegra_bo *bo = to_tegra_bo(gem);
737 
738 	tegra_bo_munmap(&bo->base, map->vaddr);
739 }
740 
741 static const struct dma_buf_ops tegra_gem_prime_dmabuf_ops = {
742 	.map_dma_buf = tegra_gem_prime_map_dma_buf,
743 	.unmap_dma_buf = tegra_gem_prime_unmap_dma_buf,
744 	.release = tegra_gem_prime_release,
745 	.begin_cpu_access = tegra_gem_prime_begin_cpu_access,
746 	.end_cpu_access = tegra_gem_prime_end_cpu_access,
747 	.mmap = tegra_gem_prime_mmap,
748 	.vmap = tegra_gem_prime_vmap,
749 	.vunmap = tegra_gem_prime_vunmap,
750 };
751 
752 struct dma_buf *tegra_gem_prime_export(struct drm_gem_object *gem,
753 				       int flags)
754 {
755 	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
756 
757 	exp_info.exp_name = KBUILD_MODNAME;
758 	exp_info.owner = gem->dev->driver->fops->owner;
759 	exp_info.ops = &tegra_gem_prime_dmabuf_ops;
760 	exp_info.size = gem->size;
761 	exp_info.flags = flags;
762 	exp_info.priv = gem;
763 
764 	return drm_gem_dmabuf_export(gem->dev, &exp_info);
765 }
766 
767 struct drm_gem_object *tegra_gem_prime_import(struct drm_device *drm,
768 					      struct dma_buf *buf)
769 {
770 	struct tegra_bo *bo;
771 
772 	if (buf->ops == &tegra_gem_prime_dmabuf_ops) {
773 		struct drm_gem_object *gem = buf->priv;
774 
775 		if (gem->dev == drm) {
776 			drm_gem_object_get(gem);
777 			return gem;
778 		}
779 	}
780 
781 	bo = tegra_bo_import(drm, buf);
782 	if (IS_ERR(bo))
783 		return ERR_CAST(bo);
784 
785 	return &bo->gem;
786 }
787 
788 struct host1x_bo *tegra_gem_lookup(struct drm_file *file, u32 handle)
789 {
790 	struct drm_gem_object *gem;
791 	struct tegra_bo *bo;
792 
793 	gem = drm_gem_object_lookup(file, handle);
794 	if (!gem)
795 		return NULL;
796 
797 	bo = to_tegra_bo(gem);
798 	return &bo->base;
799 }
800