xref: /openbmc/linux/drivers/gpu/drm/tegra/gem.c (revision ed84ef1c)
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 
16 #include <drm/drm_drv.h>
17 #include <drm/drm_prime.h>
18 #include <drm/tegra_drm.h>
19 
20 #include "drm.h"
21 #include "gem.h"
22 
23 static void tegra_bo_put(struct host1x_bo *bo)
24 {
25 	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
26 
27 	drm_gem_object_put(&obj->gem);
28 }
29 
30 /* XXX move this into lib/scatterlist.c? */
31 static int sg_alloc_table_from_sg(struct sg_table *sgt, struct scatterlist *sg,
32 				  unsigned int nents, gfp_t gfp_mask)
33 {
34 	struct scatterlist *dst;
35 	unsigned int i;
36 	int err;
37 
38 	err = sg_alloc_table(sgt, nents, gfp_mask);
39 	if (err < 0)
40 		return err;
41 
42 	dst = sgt->sgl;
43 
44 	for (i = 0; i < nents; i++) {
45 		sg_set_page(dst, sg_page(sg), sg->length, 0);
46 		dst = sg_next(dst);
47 		sg = sg_next(sg);
48 	}
49 
50 	return 0;
51 }
52 
53 static struct sg_table *tegra_bo_pin(struct device *dev, struct host1x_bo *bo,
54 				     dma_addr_t *phys)
55 {
56 	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
57 	struct sg_table *sgt;
58 	int err;
59 
60 	/*
61 	 * If we've manually mapped the buffer object through the IOMMU, make
62 	 * sure to return the IOVA address of our mapping.
63 	 *
64 	 * Similarly, for buffers that have been allocated by the DMA API the
65 	 * physical address can be used for devices that are not attached to
66 	 * an IOMMU. For these devices, callers must pass a valid pointer via
67 	 * the @phys argument.
68 	 *
69 	 * Imported buffers were also already mapped at import time, so the
70 	 * existing mapping can be reused.
71 	 */
72 	if (phys) {
73 		*phys = obj->iova;
74 		return NULL;
75 	}
76 
77 	/*
78 	 * If we don't have a mapping for this buffer yet, return an SG table
79 	 * so that host1x can do the mapping for us via the DMA API.
80 	 */
81 	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
82 	if (!sgt)
83 		return ERR_PTR(-ENOMEM);
84 
85 	if (obj->pages) {
86 		/*
87 		 * If the buffer object was allocated from the explicit IOMMU
88 		 * API code paths, construct an SG table from the pages.
89 		 */
90 		err = sg_alloc_table_from_pages(sgt, obj->pages, obj->num_pages,
91 						0, obj->gem.size, GFP_KERNEL);
92 		if (err < 0)
93 			goto free;
94 	} else if (obj->sgt) {
95 		/*
96 		 * If the buffer object already has an SG table but no pages
97 		 * were allocated for it, it means the buffer was imported and
98 		 * the SG table needs to be copied to avoid overwriting any
99 		 * other potential users of the original SG table.
100 		 */
101 		err = sg_alloc_table_from_sg(sgt, obj->sgt->sgl,
102 					     obj->sgt->orig_nents, GFP_KERNEL);
103 		if (err < 0)
104 			goto free;
105 	} else {
106 		/*
107 		 * If the buffer object had no pages allocated and if it was
108 		 * not imported, it had to be allocated with the DMA API, so
109 		 * the DMA API helper can be used.
110 		 */
111 		err = dma_get_sgtable(dev, sgt, obj->vaddr, obj->iova,
112 				      obj->gem.size);
113 		if (err < 0)
114 			goto free;
115 	}
116 
117 	return sgt;
118 
119 free:
120 	kfree(sgt);
121 	return ERR_PTR(err);
122 }
123 
124 static void tegra_bo_unpin(struct device *dev, struct sg_table *sgt)
125 {
126 	if (sgt) {
127 		sg_free_table(sgt);
128 		kfree(sgt);
129 	}
130 }
131 
132 static void *tegra_bo_mmap(struct host1x_bo *bo)
133 {
134 	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
135 	struct dma_buf_map map;
136 	int ret;
137 
138 	if (obj->vaddr) {
139 		return obj->vaddr;
140 	} else if (obj->gem.import_attach) {
141 		ret = dma_buf_vmap(obj->gem.import_attach->dmabuf, &map);
142 		return ret ? NULL : map.vaddr;
143 	} else {
144 		return vmap(obj->pages, obj->num_pages, VM_MAP,
145 			    pgprot_writecombine(PAGE_KERNEL));
146 	}
147 }
148 
149 static void tegra_bo_munmap(struct host1x_bo *bo, void *addr)
150 {
151 	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
152 	struct dma_buf_map map = DMA_BUF_MAP_INIT_VADDR(addr);
153 
154 	if (obj->vaddr)
155 		return;
156 	else if (obj->gem.import_attach)
157 		dma_buf_vunmap(obj->gem.import_attach->dmabuf, &map);
158 	else
159 		vunmap(addr);
160 }
161 
162 static struct host1x_bo *tegra_bo_get(struct host1x_bo *bo)
163 {
164 	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
165 
166 	drm_gem_object_get(&obj->gem);
167 
168 	return bo;
169 }
170 
171 static const struct host1x_bo_ops tegra_bo_ops = {
172 	.get = tegra_bo_get,
173 	.put = tegra_bo_put,
174 	.pin = tegra_bo_pin,
175 	.unpin = tegra_bo_unpin,
176 	.mmap = tegra_bo_mmap,
177 	.munmap = tegra_bo_munmap,
178 };
179 
180 static int tegra_bo_iommu_map(struct tegra_drm *tegra, struct tegra_bo *bo)
181 {
182 	int prot = IOMMU_READ | IOMMU_WRITE;
183 	int err;
184 
185 	if (bo->mm)
186 		return -EBUSY;
187 
188 	bo->mm = kzalloc(sizeof(*bo->mm), GFP_KERNEL);
189 	if (!bo->mm)
190 		return -ENOMEM;
191 
192 	mutex_lock(&tegra->mm_lock);
193 
194 	err = drm_mm_insert_node_generic(&tegra->mm,
195 					 bo->mm, bo->gem.size, PAGE_SIZE, 0, 0);
196 	if (err < 0) {
197 		dev_err(tegra->drm->dev, "out of I/O virtual memory: %d\n",
198 			err);
199 		goto unlock;
200 	}
201 
202 	bo->iova = bo->mm->start;
203 
204 	bo->size = iommu_map_sgtable(tegra->domain, bo->iova, bo->sgt, prot);
205 	if (!bo->size) {
206 		dev_err(tegra->drm->dev, "failed to map buffer\n");
207 		err = -ENOMEM;
208 		goto remove;
209 	}
210 
211 	mutex_unlock(&tegra->mm_lock);
212 
213 	return 0;
214 
215 remove:
216 	drm_mm_remove_node(bo->mm);
217 unlock:
218 	mutex_unlock(&tegra->mm_lock);
219 	kfree(bo->mm);
220 	return err;
221 }
222 
223 static int tegra_bo_iommu_unmap(struct tegra_drm *tegra, struct tegra_bo *bo)
224 {
225 	if (!bo->mm)
226 		return 0;
227 
228 	mutex_lock(&tegra->mm_lock);
229 	iommu_unmap(tegra->domain, bo->iova, bo->size);
230 	drm_mm_remove_node(bo->mm);
231 	mutex_unlock(&tegra->mm_lock);
232 
233 	kfree(bo->mm);
234 
235 	return 0;
236 }
237 
238 static const struct drm_gem_object_funcs tegra_gem_object_funcs = {
239 	.free = tegra_bo_free_object,
240 	.export = tegra_gem_prime_export,
241 	.vm_ops = &tegra_bo_vm_ops,
242 };
243 
244 static struct tegra_bo *tegra_bo_alloc_object(struct drm_device *drm,
245 					      size_t size)
246 {
247 	struct tegra_bo *bo;
248 	int err;
249 
250 	bo = kzalloc(sizeof(*bo), GFP_KERNEL);
251 	if (!bo)
252 		return ERR_PTR(-ENOMEM);
253 
254 	bo->gem.funcs = &tegra_gem_object_funcs;
255 
256 	host1x_bo_init(&bo->base, &tegra_bo_ops);
257 	size = round_up(size, PAGE_SIZE);
258 
259 	err = drm_gem_object_init(drm, &bo->gem, size);
260 	if (err < 0)
261 		goto free;
262 
263 	err = drm_gem_create_mmap_offset(&bo->gem);
264 	if (err < 0)
265 		goto release;
266 
267 	return bo;
268 
269 release:
270 	drm_gem_object_release(&bo->gem);
271 free:
272 	kfree(bo);
273 	return ERR_PTR(err);
274 }
275 
276 static void tegra_bo_free(struct drm_device *drm, struct tegra_bo *bo)
277 {
278 	if (bo->pages) {
279 		dma_unmap_sgtable(drm->dev, bo->sgt, DMA_FROM_DEVICE, 0);
280 		drm_gem_put_pages(&bo->gem, bo->pages, true, true);
281 		sg_free_table(bo->sgt);
282 		kfree(bo->sgt);
283 	} else if (bo->vaddr) {
284 		dma_free_wc(drm->dev, bo->gem.size, bo->vaddr, bo->iova);
285 	}
286 }
287 
288 static int tegra_bo_get_pages(struct drm_device *drm, struct tegra_bo *bo)
289 {
290 	int err;
291 
292 	bo->pages = drm_gem_get_pages(&bo->gem);
293 	if (IS_ERR(bo->pages))
294 		return PTR_ERR(bo->pages);
295 
296 	bo->num_pages = bo->gem.size >> PAGE_SHIFT;
297 
298 	bo->sgt = drm_prime_pages_to_sg(bo->gem.dev, bo->pages, bo->num_pages);
299 	if (IS_ERR(bo->sgt)) {
300 		err = PTR_ERR(bo->sgt);
301 		goto put_pages;
302 	}
303 
304 	err = dma_map_sgtable(drm->dev, bo->sgt, DMA_FROM_DEVICE, 0);
305 	if (err)
306 		goto free_sgt;
307 
308 	return 0;
309 
310 free_sgt:
311 	sg_free_table(bo->sgt);
312 	kfree(bo->sgt);
313 put_pages:
314 	drm_gem_put_pages(&bo->gem, bo->pages, false, false);
315 	return err;
316 }
317 
318 static int tegra_bo_alloc(struct drm_device *drm, struct tegra_bo *bo)
319 {
320 	struct tegra_drm *tegra = drm->dev_private;
321 	int err;
322 
323 	if (tegra->domain) {
324 		err = tegra_bo_get_pages(drm, bo);
325 		if (err < 0)
326 			return err;
327 
328 		err = tegra_bo_iommu_map(tegra, bo);
329 		if (err < 0) {
330 			tegra_bo_free(drm, bo);
331 			return err;
332 		}
333 	} else {
334 		size_t size = bo->gem.size;
335 
336 		bo->vaddr = dma_alloc_wc(drm->dev, size, &bo->iova,
337 					 GFP_KERNEL | __GFP_NOWARN);
338 		if (!bo->vaddr) {
339 			dev_err(drm->dev,
340 				"failed to allocate buffer of size %zu\n",
341 				size);
342 			return -ENOMEM;
343 		}
344 	}
345 
346 	return 0;
347 }
348 
349 struct tegra_bo *tegra_bo_create(struct drm_device *drm, size_t size,
350 				 unsigned long flags)
351 {
352 	struct tegra_bo *bo;
353 	int err;
354 
355 	bo = tegra_bo_alloc_object(drm, size);
356 	if (IS_ERR(bo))
357 		return bo;
358 
359 	err = tegra_bo_alloc(drm, bo);
360 	if (err < 0)
361 		goto release;
362 
363 	if (flags & DRM_TEGRA_GEM_CREATE_TILED)
364 		bo->tiling.mode = TEGRA_BO_TILING_MODE_TILED;
365 
366 	if (flags & DRM_TEGRA_GEM_CREATE_BOTTOM_UP)
367 		bo->flags |= TEGRA_BO_BOTTOM_UP;
368 
369 	return bo;
370 
371 release:
372 	drm_gem_object_release(&bo->gem);
373 	kfree(bo);
374 	return ERR_PTR(err);
375 }
376 
377 struct tegra_bo *tegra_bo_create_with_handle(struct drm_file *file,
378 					     struct drm_device *drm,
379 					     size_t size,
380 					     unsigned long flags,
381 					     u32 *handle)
382 {
383 	struct tegra_bo *bo;
384 	int err;
385 
386 	bo = tegra_bo_create(drm, size, flags);
387 	if (IS_ERR(bo))
388 		return bo;
389 
390 	err = drm_gem_handle_create(file, &bo->gem, handle);
391 	if (err) {
392 		tegra_bo_free_object(&bo->gem);
393 		return ERR_PTR(err);
394 	}
395 
396 	drm_gem_object_put(&bo->gem);
397 
398 	return bo;
399 }
400 
401 static struct tegra_bo *tegra_bo_import(struct drm_device *drm,
402 					struct dma_buf *buf)
403 {
404 	struct tegra_drm *tegra = drm->dev_private;
405 	struct dma_buf_attachment *attach;
406 	struct tegra_bo *bo;
407 	int err;
408 
409 	bo = tegra_bo_alloc_object(drm, buf->size);
410 	if (IS_ERR(bo))
411 		return bo;
412 
413 	attach = dma_buf_attach(buf, drm->dev);
414 	if (IS_ERR(attach)) {
415 		err = PTR_ERR(attach);
416 		goto free;
417 	}
418 
419 	get_dma_buf(buf);
420 
421 	bo->sgt = dma_buf_map_attachment(attach, DMA_TO_DEVICE);
422 	if (IS_ERR(bo->sgt)) {
423 		err = PTR_ERR(bo->sgt);
424 		goto detach;
425 	}
426 
427 	if (tegra->domain) {
428 		err = tegra_bo_iommu_map(tegra, bo);
429 		if (err < 0)
430 			goto detach;
431 	}
432 
433 	bo->gem.import_attach = attach;
434 
435 	return bo;
436 
437 detach:
438 	if (!IS_ERR_OR_NULL(bo->sgt))
439 		dma_buf_unmap_attachment(attach, bo->sgt, DMA_TO_DEVICE);
440 
441 	dma_buf_detach(buf, attach);
442 	dma_buf_put(buf);
443 free:
444 	drm_gem_object_release(&bo->gem);
445 	kfree(bo);
446 	return ERR_PTR(err);
447 }
448 
449 void tegra_bo_free_object(struct drm_gem_object *gem)
450 {
451 	struct tegra_drm *tegra = gem->dev->dev_private;
452 	struct tegra_bo *bo = to_tegra_bo(gem);
453 
454 	if (tegra->domain)
455 		tegra_bo_iommu_unmap(tegra, bo);
456 
457 	if (gem->import_attach) {
458 		dma_buf_unmap_attachment(gem->import_attach, bo->sgt,
459 					 DMA_TO_DEVICE);
460 		drm_prime_gem_destroy(gem, NULL);
461 	} else {
462 		tegra_bo_free(gem->dev, bo);
463 	}
464 
465 	drm_gem_object_release(gem);
466 	kfree(bo);
467 }
468 
469 int tegra_bo_dumb_create(struct drm_file *file, struct drm_device *drm,
470 			 struct drm_mode_create_dumb *args)
471 {
472 	unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
473 	struct tegra_drm *tegra = drm->dev_private;
474 	struct tegra_bo *bo;
475 
476 	args->pitch = round_up(min_pitch, tegra->pitch_align);
477 	args->size = args->pitch * args->height;
478 
479 	bo = tegra_bo_create_with_handle(file, drm, args->size, 0,
480 					 &args->handle);
481 	if (IS_ERR(bo))
482 		return PTR_ERR(bo);
483 
484 	return 0;
485 }
486 
487 static vm_fault_t tegra_bo_fault(struct vm_fault *vmf)
488 {
489 	struct vm_area_struct *vma = vmf->vma;
490 	struct drm_gem_object *gem = vma->vm_private_data;
491 	struct tegra_bo *bo = to_tegra_bo(gem);
492 	struct page *page;
493 	pgoff_t offset;
494 
495 	if (!bo->pages)
496 		return VM_FAULT_SIGBUS;
497 
498 	offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
499 	page = bo->pages[offset];
500 
501 	return vmf_insert_page(vma, vmf->address, page);
502 }
503 
504 const struct vm_operations_struct tegra_bo_vm_ops = {
505 	.fault = tegra_bo_fault,
506 	.open = drm_gem_vm_open,
507 	.close = drm_gem_vm_close,
508 };
509 
510 int __tegra_gem_mmap(struct drm_gem_object *gem, struct vm_area_struct *vma)
511 {
512 	struct tegra_bo *bo = to_tegra_bo(gem);
513 
514 	if (!bo->pages) {
515 		unsigned long vm_pgoff = vma->vm_pgoff;
516 		int err;
517 
518 		/*
519 		 * Clear the VM_PFNMAP flag that was set by drm_gem_mmap(),
520 		 * and set the vm_pgoff (used as a fake buffer offset by DRM)
521 		 * to 0 as we want to map the whole buffer.
522 		 */
523 		vma->vm_flags &= ~VM_PFNMAP;
524 		vma->vm_pgoff = 0;
525 
526 		err = dma_mmap_wc(gem->dev->dev, vma, bo->vaddr, bo->iova,
527 				  gem->size);
528 		if (err < 0) {
529 			drm_gem_vm_close(vma);
530 			return err;
531 		}
532 
533 		vma->vm_pgoff = vm_pgoff;
534 	} else {
535 		pgprot_t prot = vm_get_page_prot(vma->vm_flags);
536 
537 		vma->vm_flags |= VM_MIXEDMAP;
538 		vma->vm_flags &= ~VM_PFNMAP;
539 
540 		vma->vm_page_prot = pgprot_writecombine(prot);
541 	}
542 
543 	return 0;
544 }
545 
546 int tegra_drm_mmap(struct file *file, struct vm_area_struct *vma)
547 {
548 	struct drm_gem_object *gem;
549 	int err;
550 
551 	err = drm_gem_mmap(file, vma);
552 	if (err < 0)
553 		return err;
554 
555 	gem = vma->vm_private_data;
556 
557 	return __tegra_gem_mmap(gem, vma);
558 }
559 
560 static struct sg_table *
561 tegra_gem_prime_map_dma_buf(struct dma_buf_attachment *attach,
562 			    enum dma_data_direction dir)
563 {
564 	struct drm_gem_object *gem = attach->dmabuf->priv;
565 	struct tegra_bo *bo = to_tegra_bo(gem);
566 	struct sg_table *sgt;
567 
568 	sgt = kmalloc(sizeof(*sgt), GFP_KERNEL);
569 	if (!sgt)
570 		return NULL;
571 
572 	if (bo->pages) {
573 		if (sg_alloc_table_from_pages(sgt, bo->pages, bo->num_pages,
574 					      0, gem->size, GFP_KERNEL) < 0)
575 			goto free;
576 	} else {
577 		if (dma_get_sgtable(attach->dev, sgt, bo->vaddr, bo->iova,
578 				    gem->size) < 0)
579 			goto free;
580 	}
581 
582 	if (dma_map_sgtable(attach->dev, sgt, dir, 0))
583 		goto free;
584 
585 	return sgt;
586 
587 free:
588 	sg_free_table(sgt);
589 	kfree(sgt);
590 	return NULL;
591 }
592 
593 static void tegra_gem_prime_unmap_dma_buf(struct dma_buf_attachment *attach,
594 					  struct sg_table *sgt,
595 					  enum dma_data_direction dir)
596 {
597 	struct drm_gem_object *gem = attach->dmabuf->priv;
598 	struct tegra_bo *bo = to_tegra_bo(gem);
599 
600 	if (bo->pages)
601 		dma_unmap_sgtable(attach->dev, sgt, dir, 0);
602 
603 	sg_free_table(sgt);
604 	kfree(sgt);
605 }
606 
607 static void tegra_gem_prime_release(struct dma_buf *buf)
608 {
609 	drm_gem_dmabuf_release(buf);
610 }
611 
612 static int tegra_gem_prime_begin_cpu_access(struct dma_buf *buf,
613 					    enum dma_data_direction direction)
614 {
615 	struct drm_gem_object *gem = buf->priv;
616 	struct tegra_bo *bo = to_tegra_bo(gem);
617 	struct drm_device *drm = gem->dev;
618 
619 	if (bo->pages)
620 		dma_sync_sgtable_for_cpu(drm->dev, bo->sgt, DMA_FROM_DEVICE);
621 
622 	return 0;
623 }
624 
625 static int tegra_gem_prime_end_cpu_access(struct dma_buf *buf,
626 					  enum dma_data_direction direction)
627 {
628 	struct drm_gem_object *gem = buf->priv;
629 	struct tegra_bo *bo = to_tegra_bo(gem);
630 	struct drm_device *drm = gem->dev;
631 
632 	if (bo->pages)
633 		dma_sync_sgtable_for_device(drm->dev, bo->sgt, DMA_TO_DEVICE);
634 
635 	return 0;
636 }
637 
638 static int tegra_gem_prime_mmap(struct dma_buf *buf, struct vm_area_struct *vma)
639 {
640 	struct drm_gem_object *gem = buf->priv;
641 	int err;
642 
643 	err = drm_gem_mmap_obj(gem, gem->size, vma);
644 	if (err < 0)
645 		return err;
646 
647 	return __tegra_gem_mmap(gem, vma);
648 }
649 
650 static int tegra_gem_prime_vmap(struct dma_buf *buf, struct dma_buf_map *map)
651 {
652 	struct drm_gem_object *gem = buf->priv;
653 	struct tegra_bo *bo = to_tegra_bo(gem);
654 
655 	dma_buf_map_set_vaddr(map, bo->vaddr);
656 
657 	return 0;
658 }
659 
660 static void tegra_gem_prime_vunmap(struct dma_buf *buf, struct dma_buf_map *map)
661 {
662 }
663 
664 static const struct dma_buf_ops tegra_gem_prime_dmabuf_ops = {
665 	.map_dma_buf = tegra_gem_prime_map_dma_buf,
666 	.unmap_dma_buf = tegra_gem_prime_unmap_dma_buf,
667 	.release = tegra_gem_prime_release,
668 	.begin_cpu_access = tegra_gem_prime_begin_cpu_access,
669 	.end_cpu_access = tegra_gem_prime_end_cpu_access,
670 	.mmap = tegra_gem_prime_mmap,
671 	.vmap = tegra_gem_prime_vmap,
672 	.vunmap = tegra_gem_prime_vunmap,
673 };
674 
675 struct dma_buf *tegra_gem_prime_export(struct drm_gem_object *gem,
676 				       int flags)
677 {
678 	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
679 
680 	exp_info.exp_name = KBUILD_MODNAME;
681 	exp_info.owner = gem->dev->driver->fops->owner;
682 	exp_info.ops = &tegra_gem_prime_dmabuf_ops;
683 	exp_info.size = gem->size;
684 	exp_info.flags = flags;
685 	exp_info.priv = gem;
686 
687 	return drm_gem_dmabuf_export(gem->dev, &exp_info);
688 }
689 
690 struct drm_gem_object *tegra_gem_prime_import(struct drm_device *drm,
691 					      struct dma_buf *buf)
692 {
693 	struct tegra_bo *bo;
694 
695 	if (buf->ops == &tegra_gem_prime_dmabuf_ops) {
696 		struct drm_gem_object *gem = buf->priv;
697 
698 		if (gem->dev == drm) {
699 			drm_gem_object_get(gem);
700 			return gem;
701 		}
702 	}
703 
704 	bo = tegra_bo_import(drm, buf);
705 	if (IS_ERR(bo))
706 		return ERR_CAST(bo);
707 
708 	return &bo->gem;
709 }
710 
711 struct host1x_bo *tegra_gem_lookup(struct drm_file *file, u32 handle)
712 {
713 	struct drm_gem_object *gem;
714 	struct tegra_bo *bo;
715 
716 	gem = drm_gem_object_lookup(file, handle);
717 	if (!gem)
718 		return NULL;
719 
720 	bo = to_tegra_bo(gem);
721 	return &bo->base;
722 }
723