xref: /kernel/linux/linux-6.6/drivers/gpu/drm/tegra/gem.c (revision 62306a36)
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
25MODULE_IMPORT_NS(DMA_BUF);
26
27static 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
47static inline unsigned int sgt_dma_count_chunks(struct sg_table *sgt)
48{
49	return sg_dma_count_chunks(sgt->sgl, sgt->nents);
50}
51
52static 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
59static 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
136out:
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
153free_sgt:
154	sg_free_table(map->sgt);
155free:
156	kfree(map->sgt);
157	kfree(map);
158	return ERR_PTR(err);
159}
160
161static 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
177static void *tegra_bo_mmap(struct host1x_bo *bo)
178{
179	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
180	struct iosys_map map;
181	int ret;
182
183	if (obj->vaddr) {
184		return obj->vaddr;
185	} else if (obj->gem.import_attach) {
186		ret = dma_buf_vmap_unlocked(obj->gem.import_attach->dmabuf, &map);
187		return ret ? NULL : map.vaddr;
188	} else {
189		return vmap(obj->pages, obj->num_pages, VM_MAP,
190			    pgprot_writecombine(PAGE_KERNEL));
191	}
192}
193
194static void tegra_bo_munmap(struct host1x_bo *bo, void *addr)
195{
196	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
197	struct iosys_map map = IOSYS_MAP_INIT_VADDR(addr);
198
199	if (obj->vaddr)
200		return;
201	else if (obj->gem.import_attach)
202		dma_buf_vunmap_unlocked(obj->gem.import_attach->dmabuf, &map);
203	else
204		vunmap(addr);
205}
206
207static struct host1x_bo *tegra_bo_get(struct host1x_bo *bo)
208{
209	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
210
211	drm_gem_object_get(&obj->gem);
212
213	return bo;
214}
215
216static const struct host1x_bo_ops tegra_bo_ops = {
217	.get = tegra_bo_get,
218	.put = tegra_bo_put,
219	.pin = tegra_bo_pin,
220	.unpin = tegra_bo_unpin,
221	.mmap = tegra_bo_mmap,
222	.munmap = tegra_bo_munmap,
223};
224
225static int tegra_bo_iommu_map(struct tegra_drm *tegra, struct tegra_bo *bo)
226{
227	int prot = IOMMU_READ | IOMMU_WRITE;
228	int err;
229
230	if (bo->mm)
231		return -EBUSY;
232
233	bo->mm = kzalloc(sizeof(*bo->mm), GFP_KERNEL);
234	if (!bo->mm)
235		return -ENOMEM;
236
237	mutex_lock(&tegra->mm_lock);
238
239	err = drm_mm_insert_node_generic(&tegra->mm,
240					 bo->mm, bo->gem.size, PAGE_SIZE, 0, 0);
241	if (err < 0) {
242		dev_err(tegra->drm->dev, "out of I/O virtual memory: %d\n",
243			err);
244		goto unlock;
245	}
246
247	bo->iova = bo->mm->start;
248
249	bo->size = iommu_map_sgtable(tegra->domain, bo->iova, bo->sgt, prot);
250	if (!bo->size) {
251		dev_err(tegra->drm->dev, "failed to map buffer\n");
252		err = -ENOMEM;
253		goto remove;
254	}
255
256	mutex_unlock(&tegra->mm_lock);
257
258	return 0;
259
260remove:
261	drm_mm_remove_node(bo->mm);
262unlock:
263	mutex_unlock(&tegra->mm_lock);
264	kfree(bo->mm);
265	return err;
266}
267
268static int tegra_bo_iommu_unmap(struct tegra_drm *tegra, struct tegra_bo *bo)
269{
270	if (!bo->mm)
271		return 0;
272
273	mutex_lock(&tegra->mm_lock);
274	iommu_unmap(tegra->domain, bo->iova, bo->size);
275	drm_mm_remove_node(bo->mm);
276	mutex_unlock(&tegra->mm_lock);
277
278	kfree(bo->mm);
279
280	return 0;
281}
282
283static const struct drm_gem_object_funcs tegra_gem_object_funcs = {
284	.free = tegra_bo_free_object,
285	.export = tegra_gem_prime_export,
286	.vm_ops = &tegra_bo_vm_ops,
287};
288
289static struct tegra_bo *tegra_bo_alloc_object(struct drm_device *drm,
290					      size_t size)
291{
292	struct tegra_bo *bo;
293	int err;
294
295	bo = kzalloc(sizeof(*bo), GFP_KERNEL);
296	if (!bo)
297		return ERR_PTR(-ENOMEM);
298
299	bo->gem.funcs = &tegra_gem_object_funcs;
300
301	host1x_bo_init(&bo->base, &tegra_bo_ops);
302	size = round_up(size, PAGE_SIZE);
303
304	err = drm_gem_object_init(drm, &bo->gem, size);
305	if (err < 0)
306		goto free;
307
308	err = drm_gem_create_mmap_offset(&bo->gem);
309	if (err < 0)
310		goto release;
311
312	return bo;
313
314release:
315	drm_gem_object_release(&bo->gem);
316free:
317	kfree(bo);
318	return ERR_PTR(err);
319}
320
321static void tegra_bo_free(struct drm_device *drm, struct tegra_bo *bo)
322{
323	if (bo->pages) {
324		dma_unmap_sgtable(drm->dev, bo->sgt, DMA_FROM_DEVICE, 0);
325		drm_gem_put_pages(&bo->gem, bo->pages, true, true);
326		sg_free_table(bo->sgt);
327		kfree(bo->sgt);
328	} else if (bo->vaddr) {
329		dma_free_wc(drm->dev, bo->gem.size, bo->vaddr, bo->iova);
330	}
331}
332
333static int tegra_bo_get_pages(struct drm_device *drm, struct tegra_bo *bo)
334{
335	int err;
336
337	bo->pages = drm_gem_get_pages(&bo->gem);
338	if (IS_ERR(bo->pages))
339		return PTR_ERR(bo->pages);
340
341	bo->num_pages = bo->gem.size >> PAGE_SHIFT;
342
343	bo->sgt = drm_prime_pages_to_sg(bo->gem.dev, bo->pages, bo->num_pages);
344	if (IS_ERR(bo->sgt)) {
345		err = PTR_ERR(bo->sgt);
346		goto put_pages;
347	}
348
349	err = dma_map_sgtable(drm->dev, bo->sgt, DMA_FROM_DEVICE, 0);
350	if (err)
351		goto free_sgt;
352
353	return 0;
354
355free_sgt:
356	sg_free_table(bo->sgt);
357	kfree(bo->sgt);
358put_pages:
359	drm_gem_put_pages(&bo->gem, bo->pages, false, false);
360	return err;
361}
362
363static int tegra_bo_alloc(struct drm_device *drm, struct tegra_bo *bo)
364{
365	struct tegra_drm *tegra = drm->dev_private;
366	int err;
367
368	if (tegra->domain) {
369		err = tegra_bo_get_pages(drm, bo);
370		if (err < 0)
371			return err;
372
373		err = tegra_bo_iommu_map(tegra, bo);
374		if (err < 0) {
375			tegra_bo_free(drm, bo);
376			return err;
377		}
378	} else {
379		size_t size = bo->gem.size;
380
381		bo->vaddr = dma_alloc_wc(drm->dev, size, &bo->iova,
382					 GFP_KERNEL | __GFP_NOWARN);
383		if (!bo->vaddr) {
384			dev_err(drm->dev,
385				"failed to allocate buffer of size %zu\n",
386				size);
387			return -ENOMEM;
388		}
389	}
390
391	return 0;
392}
393
394struct tegra_bo *tegra_bo_create(struct drm_device *drm, size_t size,
395				 unsigned long flags)
396{
397	struct tegra_bo *bo;
398	int err;
399
400	bo = tegra_bo_alloc_object(drm, size);
401	if (IS_ERR(bo))
402		return bo;
403
404	err = tegra_bo_alloc(drm, bo);
405	if (err < 0)
406		goto release;
407
408	if (flags & DRM_TEGRA_GEM_CREATE_TILED)
409		bo->tiling.mode = TEGRA_BO_TILING_MODE_TILED;
410
411	if (flags & DRM_TEGRA_GEM_CREATE_BOTTOM_UP)
412		bo->flags |= TEGRA_BO_BOTTOM_UP;
413
414	return bo;
415
416release:
417	drm_gem_object_release(&bo->gem);
418	kfree(bo);
419	return ERR_PTR(err);
420}
421
422struct tegra_bo *tegra_bo_create_with_handle(struct drm_file *file,
423					     struct drm_device *drm,
424					     size_t size,
425					     unsigned long flags,
426					     u32 *handle)
427{
428	struct tegra_bo *bo;
429	int err;
430
431	bo = tegra_bo_create(drm, size, flags);
432	if (IS_ERR(bo))
433		return bo;
434
435	err = drm_gem_handle_create(file, &bo->gem, handle);
436	if (err) {
437		tegra_bo_free_object(&bo->gem);
438		return ERR_PTR(err);
439	}
440
441	drm_gem_object_put(&bo->gem);
442
443	return bo;
444}
445
446static struct tegra_bo *tegra_bo_import(struct drm_device *drm,
447					struct dma_buf *buf)
448{
449	struct tegra_drm *tegra = drm->dev_private;
450	struct dma_buf_attachment *attach;
451	struct tegra_bo *bo;
452	int err;
453
454	bo = tegra_bo_alloc_object(drm, buf->size);
455	if (IS_ERR(bo))
456		return bo;
457
458	attach = dma_buf_attach(buf, drm->dev);
459	if (IS_ERR(attach)) {
460		err = PTR_ERR(attach);
461		goto free;
462	}
463
464	get_dma_buf(buf);
465
466	bo->sgt = dma_buf_map_attachment_unlocked(attach, DMA_TO_DEVICE);
467	if (IS_ERR(bo->sgt)) {
468		err = PTR_ERR(bo->sgt);
469		goto detach;
470	}
471
472	if (tegra->domain) {
473		err = tegra_bo_iommu_map(tegra, bo);
474		if (err < 0)
475			goto detach;
476	}
477
478	bo->gem.import_attach = attach;
479
480	return bo;
481
482detach:
483	if (!IS_ERR_OR_NULL(bo->sgt))
484		dma_buf_unmap_attachment_unlocked(attach, bo->sgt, DMA_TO_DEVICE);
485
486	dma_buf_detach(buf, attach);
487	dma_buf_put(buf);
488free:
489	drm_gem_object_release(&bo->gem);
490	kfree(bo);
491	return ERR_PTR(err);
492}
493
494void tegra_bo_free_object(struct drm_gem_object *gem)
495{
496	struct tegra_drm *tegra = gem->dev->dev_private;
497	struct host1x_bo_mapping *mapping, *tmp;
498	struct tegra_bo *bo = to_tegra_bo(gem);
499
500	/* remove all mappings of this buffer object from any caches */
501	list_for_each_entry_safe(mapping, tmp, &bo->base.mappings, list) {
502		if (mapping->cache)
503			host1x_bo_unpin(mapping);
504		else
505			dev_err(gem->dev->dev, "mapping %p stale for device %s\n", mapping,
506				dev_name(mapping->dev));
507	}
508
509	if (tegra->domain)
510		tegra_bo_iommu_unmap(tegra, bo);
511
512	if (gem->import_attach) {
513		dma_buf_unmap_attachment_unlocked(gem->import_attach, bo->sgt,
514						  DMA_TO_DEVICE);
515		drm_prime_gem_destroy(gem, NULL);
516	} else {
517		tegra_bo_free(gem->dev, bo);
518	}
519
520	drm_gem_object_release(gem);
521	kfree(bo);
522}
523
524int tegra_bo_dumb_create(struct drm_file *file, struct drm_device *drm,
525			 struct drm_mode_create_dumb *args)
526{
527	unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
528	struct tegra_drm *tegra = drm->dev_private;
529	struct tegra_bo *bo;
530
531	args->pitch = round_up(min_pitch, tegra->pitch_align);
532	args->size = args->pitch * args->height;
533
534	bo = tegra_bo_create_with_handle(file, drm, args->size, 0,
535					 &args->handle);
536	if (IS_ERR(bo))
537		return PTR_ERR(bo);
538
539	return 0;
540}
541
542static vm_fault_t tegra_bo_fault(struct vm_fault *vmf)
543{
544	struct vm_area_struct *vma = vmf->vma;
545	struct drm_gem_object *gem = vma->vm_private_data;
546	struct tegra_bo *bo = to_tegra_bo(gem);
547	struct page *page;
548	pgoff_t offset;
549
550	if (!bo->pages)
551		return VM_FAULT_SIGBUS;
552
553	offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
554	page = bo->pages[offset];
555
556	return vmf_insert_page(vma, vmf->address, page);
557}
558
559const struct vm_operations_struct tegra_bo_vm_ops = {
560	.fault = tegra_bo_fault,
561	.open = drm_gem_vm_open,
562	.close = drm_gem_vm_close,
563};
564
565int __tegra_gem_mmap(struct drm_gem_object *gem, struct vm_area_struct *vma)
566{
567	struct tegra_bo *bo = to_tegra_bo(gem);
568
569	if (!bo->pages) {
570		unsigned long vm_pgoff = vma->vm_pgoff;
571		int err;
572
573		/*
574		 * Clear the VM_PFNMAP flag that was set by drm_gem_mmap(),
575		 * and set the vm_pgoff (used as a fake buffer offset by DRM)
576		 * to 0 as we want to map the whole buffer.
577		 */
578		vm_flags_clear(vma, VM_PFNMAP);
579		vma->vm_pgoff = 0;
580
581		err = dma_mmap_wc(gem->dev->dev, vma, bo->vaddr, bo->iova,
582				  gem->size);
583		if (err < 0) {
584			drm_gem_vm_close(vma);
585			return err;
586		}
587
588		vma->vm_pgoff = vm_pgoff;
589	} else {
590		pgprot_t prot = vm_get_page_prot(vma->vm_flags);
591
592		vm_flags_mod(vma, VM_MIXEDMAP, VM_PFNMAP);
593
594		vma->vm_page_prot = pgprot_writecombine(prot);
595	}
596
597	return 0;
598}
599
600int tegra_drm_mmap(struct file *file, struct vm_area_struct *vma)
601{
602	struct drm_gem_object *gem;
603	int err;
604
605	err = drm_gem_mmap(file, vma);
606	if (err < 0)
607		return err;
608
609	gem = vma->vm_private_data;
610
611	return __tegra_gem_mmap(gem, vma);
612}
613
614static struct sg_table *
615tegra_gem_prime_map_dma_buf(struct dma_buf_attachment *attach,
616			    enum dma_data_direction dir)
617{
618	struct drm_gem_object *gem = attach->dmabuf->priv;
619	struct tegra_bo *bo = to_tegra_bo(gem);
620	struct sg_table *sgt;
621
622	sgt = kmalloc(sizeof(*sgt), GFP_KERNEL);
623	if (!sgt)
624		return NULL;
625
626	if (bo->pages) {
627		if (sg_alloc_table_from_pages(sgt, bo->pages, bo->num_pages,
628					      0, gem->size, GFP_KERNEL) < 0)
629			goto free;
630	} else {
631		if (dma_get_sgtable(attach->dev, sgt, bo->vaddr, bo->iova,
632				    gem->size) < 0)
633			goto free;
634	}
635
636	if (dma_map_sgtable(attach->dev, sgt, dir, 0))
637		goto free;
638
639	return sgt;
640
641free:
642	sg_free_table(sgt);
643	kfree(sgt);
644	return NULL;
645}
646
647static void tegra_gem_prime_unmap_dma_buf(struct dma_buf_attachment *attach,
648					  struct sg_table *sgt,
649					  enum dma_data_direction dir)
650{
651	struct drm_gem_object *gem = attach->dmabuf->priv;
652	struct tegra_bo *bo = to_tegra_bo(gem);
653
654	if (bo->pages)
655		dma_unmap_sgtable(attach->dev, sgt, dir, 0);
656
657	sg_free_table(sgt);
658	kfree(sgt);
659}
660
661static void tegra_gem_prime_release(struct dma_buf *buf)
662{
663	drm_gem_dmabuf_release(buf);
664}
665
666static int tegra_gem_prime_begin_cpu_access(struct dma_buf *buf,
667					    enum dma_data_direction direction)
668{
669	struct drm_gem_object *gem = buf->priv;
670	struct tegra_bo *bo = to_tegra_bo(gem);
671	struct drm_device *drm = gem->dev;
672
673	if (bo->pages)
674		dma_sync_sgtable_for_cpu(drm->dev, bo->sgt, DMA_FROM_DEVICE);
675
676	return 0;
677}
678
679static int tegra_gem_prime_end_cpu_access(struct dma_buf *buf,
680					  enum dma_data_direction direction)
681{
682	struct drm_gem_object *gem = buf->priv;
683	struct tegra_bo *bo = to_tegra_bo(gem);
684	struct drm_device *drm = gem->dev;
685
686	if (bo->pages)
687		dma_sync_sgtable_for_device(drm->dev, bo->sgt, DMA_TO_DEVICE);
688
689	return 0;
690}
691
692static int tegra_gem_prime_mmap(struct dma_buf *buf, struct vm_area_struct *vma)
693{
694	struct drm_gem_object *gem = buf->priv;
695	int err;
696
697	err = drm_gem_mmap_obj(gem, gem->size, vma);
698	if (err < 0)
699		return err;
700
701	return __tegra_gem_mmap(gem, vma);
702}
703
704static int tegra_gem_prime_vmap(struct dma_buf *buf, struct iosys_map *map)
705{
706	struct drm_gem_object *gem = buf->priv;
707	struct tegra_bo *bo = to_tegra_bo(gem);
708	void *vaddr;
709
710	vaddr = tegra_bo_mmap(&bo->base);
711	if (IS_ERR(vaddr))
712		return PTR_ERR(vaddr);
713
714	iosys_map_set_vaddr(map, vaddr);
715
716	return 0;
717}
718
719static void tegra_gem_prime_vunmap(struct dma_buf *buf, struct iosys_map *map)
720{
721	struct drm_gem_object *gem = buf->priv;
722	struct tegra_bo *bo = to_tegra_bo(gem);
723
724	tegra_bo_munmap(&bo->base, map->vaddr);
725}
726
727static const struct dma_buf_ops tegra_gem_prime_dmabuf_ops = {
728	.map_dma_buf = tegra_gem_prime_map_dma_buf,
729	.unmap_dma_buf = tegra_gem_prime_unmap_dma_buf,
730	.release = tegra_gem_prime_release,
731	.begin_cpu_access = tegra_gem_prime_begin_cpu_access,
732	.end_cpu_access = tegra_gem_prime_end_cpu_access,
733	.mmap = tegra_gem_prime_mmap,
734	.vmap = tegra_gem_prime_vmap,
735	.vunmap = tegra_gem_prime_vunmap,
736};
737
738struct dma_buf *tegra_gem_prime_export(struct drm_gem_object *gem,
739				       int flags)
740{
741	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
742
743	exp_info.exp_name = KBUILD_MODNAME;
744	exp_info.owner = gem->dev->driver->fops->owner;
745	exp_info.ops = &tegra_gem_prime_dmabuf_ops;
746	exp_info.size = gem->size;
747	exp_info.flags = flags;
748	exp_info.priv = gem;
749
750	return drm_gem_dmabuf_export(gem->dev, &exp_info);
751}
752
753struct drm_gem_object *tegra_gem_prime_import(struct drm_device *drm,
754					      struct dma_buf *buf)
755{
756	struct tegra_bo *bo;
757
758	if (buf->ops == &tegra_gem_prime_dmabuf_ops) {
759		struct drm_gem_object *gem = buf->priv;
760
761		if (gem->dev == drm) {
762			drm_gem_object_get(gem);
763			return gem;
764		}
765	}
766
767	bo = tegra_bo_import(drm, buf);
768	if (IS_ERR(bo))
769		return ERR_CAST(bo);
770
771	return &bo->gem;
772}
773
774struct host1x_bo *tegra_gem_lookup(struct drm_file *file, u32 handle)
775{
776	struct drm_gem_object *gem;
777	struct tegra_bo *bo;
778
779	gem = drm_gem_object_lookup(file, handle);
780	if (!gem)
781		return NULL;
782
783	bo = to_tegra_bo(gem);
784	return &bo->base;
785}
786