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v6.2
  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
 17#include <drm/drm_drv.h>
 18#include <drm/drm_prime.h>
 19#include <drm/tegra_drm.h>
 20
 21#include "drm.h"
 22#include "gem.h"
 23
 24MODULE_IMPORT_NS(DMA_BUF);
 25
 26static unsigned int sg_dma_count_chunks(struct scatterlist *sgl, unsigned int nents)
 27{
 28	dma_addr_t next = ~(dma_addr_t)0;
 29	unsigned int count = 0, i;
 30	struct scatterlist *s;
 31
 32	for_each_sg(sgl, s, nents, i) {
 33		/* sg_dma_address(s) is only valid for entries that have sg_dma_len(s) != 0. */
 34		if (!sg_dma_len(s))
 35			continue;
 36
 37		if (sg_dma_address(s) != next) {
 38			next = sg_dma_address(s) + sg_dma_len(s);
 39			count++;
 40		}
 41	}
 42
 43	return count;
 44}
 45
 46static inline unsigned int sgt_dma_count_chunks(struct sg_table *sgt)
 47{
 48	return sg_dma_count_chunks(sgt->sgl, sgt->nents);
 49}
 50
 51static void tegra_bo_put(struct host1x_bo *bo)
 52{
 53	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
 54
 55	drm_gem_object_put(&obj->gem);
 56}
 57
 58static struct host1x_bo_mapping *tegra_bo_pin(struct device *dev, struct host1x_bo *bo,
 59					      enum dma_data_direction direction)
 
 60{
 61	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
 62	struct drm_gem_object *gem = &obj->gem;
 63	struct host1x_bo_mapping *map;
 64	int err;
 65
 66	map = kzalloc(sizeof(*map), GFP_KERNEL);
 67	if (!map)
 68		return ERR_PTR(-ENOMEM);
 69
 70	kref_init(&map->ref);
 71	map->bo = host1x_bo_get(bo);
 72	map->direction = direction;
 73	map->dev = dev;
 74
 75	/*
 76	 * Imported buffers need special treatment to satisfy the semantics of DMA-BUF.
 77	 */
 78	if (gem->import_attach) {
 79		struct dma_buf *buf = gem->import_attach->dmabuf;
 80
 81		map->attach = dma_buf_attach(buf, dev);
 82		if (IS_ERR(map->attach)) {
 83			err = PTR_ERR(map->attach);
 84			goto free;
 85		}
 86
 87		map->sgt = dma_buf_map_attachment_unlocked(map->attach, direction);
 88		if (IS_ERR(map->sgt)) {
 89			dma_buf_detach(buf, map->attach);
 90			err = PTR_ERR(map->sgt);
 91			map->sgt = NULL;
 92			goto free;
 93		}
 94
 95		err = sgt_dma_count_chunks(map->sgt);
 96		map->size = gem->size;
 
 
 
 
 97
 98		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 99	}
100
101	/*
102	 * If we don't have a mapping for this buffer yet, return an SG table
103	 * so that host1x can do the mapping for us via the DMA API.
104	 */
105	map->sgt = kzalloc(sizeof(*map->sgt), GFP_KERNEL);
106	if (!map->sgt) {
107		err = -ENOMEM;
108		goto free;
109	}
110
111	if (obj->pages) {
112		/*
113		 * If the buffer object was allocated from the explicit IOMMU
114		 * API code paths, construct an SG table from the pages.
115		 */
116		err = sg_alloc_table_from_pages(map->sgt, obj->pages, obj->num_pages, 0, gem->size,
117						GFP_KERNEL);
 
 
 
 
 
 
 
 
 
 
 
118		if (err < 0)
119			goto free;
120	} else {
121		/*
122		 * If the buffer object had no pages allocated and if it was
123		 * not imported, it had to be allocated with the DMA API, so
124		 * the DMA API helper can be used.
125		 */
126		err = dma_get_sgtable(dev, map->sgt, obj->vaddr, obj->iova, gem->size);
 
127		if (err < 0)
128			goto free;
129	}
130
131	err = dma_map_sgtable(dev, map->sgt, direction, 0);
132	if (err)
133		goto free_sgt;
134
135out:
136	/*
137	 * If we've manually mapped the buffer object through the IOMMU, make sure to return the
138	 * existing IOVA address of our mapping.
139	 */
140	if (!obj->mm) {
141		map->phys = sg_dma_address(map->sgt->sgl);
142		map->chunks = err;
143	} else {
144		map->phys = obj->iova;
145		map->chunks = 1;
146	}
147
148	map->size = gem->size;
149
150	return map;
151
152free_sgt:
153	sg_free_table(map->sgt);
154free:
155	kfree(map->sgt);
156	kfree(map);
157	return ERR_PTR(err);
158}
159
160static void tegra_bo_unpin(struct host1x_bo_mapping *map)
161{
162	if (map->attach) {
163		dma_buf_unmap_attachment_unlocked(map->attach, map->sgt,
164						  map->direction);
165		dma_buf_detach(map->attach->dmabuf, map->attach);
166	} else {
167		dma_unmap_sgtable(map->dev, map->sgt, map->direction, 0);
168		sg_free_table(map->sgt);
169		kfree(map->sgt);
170	}
171
172	host1x_bo_put(map->bo);
173	kfree(map);
174}
175
176static void *tegra_bo_mmap(struct host1x_bo *bo)
177{
178	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
179	struct iosys_map map;
180	int ret;
181
182	if (obj->vaddr) {
183		return obj->vaddr;
184	} else if (obj->gem.import_attach) {
185		ret = dma_buf_vmap_unlocked(obj->gem.import_attach->dmabuf, &map);
186		return ret ? NULL : map.vaddr;
187	} else {
188		return vmap(obj->pages, obj->num_pages, VM_MAP,
189			    pgprot_writecombine(PAGE_KERNEL));
190	}
191}
192
193static void tegra_bo_munmap(struct host1x_bo *bo, void *addr)
194{
195	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
196	struct iosys_map map = IOSYS_MAP_INIT_VADDR(addr);
197
198	if (obj->vaddr)
199		return;
200	else if (obj->gem.import_attach)
201		dma_buf_vunmap_unlocked(obj->gem.import_attach->dmabuf, &map);
202	else
203		vunmap(addr);
204}
205
206static struct host1x_bo *tegra_bo_get(struct host1x_bo *bo)
207{
208	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
209
210	drm_gem_object_get(&obj->gem);
211
212	return bo;
213}
214
215static const struct host1x_bo_ops tegra_bo_ops = {
216	.get = tegra_bo_get,
217	.put = tegra_bo_put,
218	.pin = tegra_bo_pin,
219	.unpin = tegra_bo_unpin,
220	.mmap = tegra_bo_mmap,
221	.munmap = tegra_bo_munmap,
222};
223
224static int tegra_bo_iommu_map(struct tegra_drm *tegra, struct tegra_bo *bo)
225{
226	int prot = IOMMU_READ | IOMMU_WRITE;
227	int err;
228
229	if (bo->mm)
230		return -EBUSY;
231
232	bo->mm = kzalloc(sizeof(*bo->mm), GFP_KERNEL);
233	if (!bo->mm)
234		return -ENOMEM;
235
236	mutex_lock(&tegra->mm_lock);
237
238	err = drm_mm_insert_node_generic(&tegra->mm,
239					 bo->mm, bo->gem.size, PAGE_SIZE, 0, 0);
240	if (err < 0) {
241		dev_err(tegra->drm->dev, "out of I/O virtual memory: %d\n",
242			err);
243		goto unlock;
244	}
245
246	bo->iova = bo->mm->start;
247
248	bo->size = iommu_map_sgtable(tegra->domain, bo->iova, bo->sgt, prot);
249	if (!bo->size) {
250		dev_err(tegra->drm->dev, "failed to map buffer\n");
251		err = -ENOMEM;
252		goto remove;
253	}
254
255	mutex_unlock(&tegra->mm_lock);
256
257	return 0;
258
259remove:
260	drm_mm_remove_node(bo->mm);
261unlock:
262	mutex_unlock(&tegra->mm_lock);
263	kfree(bo->mm);
264	return err;
265}
266
267static int tegra_bo_iommu_unmap(struct tegra_drm *tegra, struct tegra_bo *bo)
268{
269	if (!bo->mm)
270		return 0;
271
272	mutex_lock(&tegra->mm_lock);
273	iommu_unmap(tegra->domain, bo->iova, bo->size);
274	drm_mm_remove_node(bo->mm);
275	mutex_unlock(&tegra->mm_lock);
276
277	kfree(bo->mm);
278
279	return 0;
280}
281
282static const struct drm_gem_object_funcs tegra_gem_object_funcs = {
283	.free = tegra_bo_free_object,
284	.export = tegra_gem_prime_export,
285	.vm_ops = &tegra_bo_vm_ops,
286};
287
288static struct tegra_bo *tegra_bo_alloc_object(struct drm_device *drm,
289					      size_t size)
290{
291	struct tegra_bo *bo;
292	int err;
293
294	bo = kzalloc(sizeof(*bo), GFP_KERNEL);
295	if (!bo)
296		return ERR_PTR(-ENOMEM);
297
298	bo->gem.funcs = &tegra_gem_object_funcs;
299
300	host1x_bo_init(&bo->base, &tegra_bo_ops);
301	size = round_up(size, PAGE_SIZE);
302
303	err = drm_gem_object_init(drm, &bo->gem, size);
304	if (err < 0)
305		goto free;
306
307	err = drm_gem_create_mmap_offset(&bo->gem);
308	if (err < 0)
309		goto release;
310
311	return bo;
312
313release:
314	drm_gem_object_release(&bo->gem);
315free:
316	kfree(bo);
317	return ERR_PTR(err);
318}
319
320static void tegra_bo_free(struct drm_device *drm, struct tegra_bo *bo)
321{
322	if (bo->pages) {
323		dma_unmap_sgtable(drm->dev, bo->sgt, DMA_FROM_DEVICE, 0);
324		drm_gem_put_pages(&bo->gem, bo->pages, true, true);
325		sg_free_table(bo->sgt);
326		kfree(bo->sgt);
327	} else if (bo->vaddr) {
328		dma_free_wc(drm->dev, bo->gem.size, bo->vaddr, bo->iova);
329	}
330}
331
332static int tegra_bo_get_pages(struct drm_device *drm, struct tegra_bo *bo)
333{
334	int err;
335
336	bo->pages = drm_gem_get_pages(&bo->gem);
337	if (IS_ERR(bo->pages))
338		return PTR_ERR(bo->pages);
339
340	bo->num_pages = bo->gem.size >> PAGE_SHIFT;
341
342	bo->sgt = drm_prime_pages_to_sg(bo->gem.dev, bo->pages, bo->num_pages);
343	if (IS_ERR(bo->sgt)) {
344		err = PTR_ERR(bo->sgt);
345		goto put_pages;
346	}
347
348	err = dma_map_sgtable(drm->dev, bo->sgt, DMA_FROM_DEVICE, 0);
349	if (err)
350		goto free_sgt;
351
352	return 0;
353
354free_sgt:
355	sg_free_table(bo->sgt);
356	kfree(bo->sgt);
357put_pages:
358	drm_gem_put_pages(&bo->gem, bo->pages, false, false);
359	return err;
360}
361
362static int tegra_bo_alloc(struct drm_device *drm, struct tegra_bo *bo)
363{
364	struct tegra_drm *tegra = drm->dev_private;
365	int err;
366
367	if (tegra->domain) {
368		err = tegra_bo_get_pages(drm, bo);
369		if (err < 0)
370			return err;
371
372		err = tegra_bo_iommu_map(tegra, bo);
373		if (err < 0) {
374			tegra_bo_free(drm, bo);
375			return err;
376		}
377	} else {
378		size_t size = bo->gem.size;
379
380		bo->vaddr = dma_alloc_wc(drm->dev, size, &bo->iova,
381					 GFP_KERNEL | __GFP_NOWARN);
382		if (!bo->vaddr) {
383			dev_err(drm->dev,
384				"failed to allocate buffer of size %zu\n",
385				size);
386			return -ENOMEM;
387		}
388	}
389
390	return 0;
391}
392
393struct tegra_bo *tegra_bo_create(struct drm_device *drm, size_t size,
394				 unsigned long flags)
395{
396	struct tegra_bo *bo;
397	int err;
398
399	bo = tegra_bo_alloc_object(drm, size);
400	if (IS_ERR(bo))
401		return bo;
402
403	err = tegra_bo_alloc(drm, bo);
404	if (err < 0)
405		goto release;
406
407	if (flags & DRM_TEGRA_GEM_CREATE_TILED)
408		bo->tiling.mode = TEGRA_BO_TILING_MODE_TILED;
409
410	if (flags & DRM_TEGRA_GEM_CREATE_BOTTOM_UP)
411		bo->flags |= TEGRA_BO_BOTTOM_UP;
412
413	return bo;
414
415release:
416	drm_gem_object_release(&bo->gem);
417	kfree(bo);
418	return ERR_PTR(err);
419}
420
421struct tegra_bo *tegra_bo_create_with_handle(struct drm_file *file,
422					     struct drm_device *drm,
423					     size_t size,
424					     unsigned long flags,
425					     u32 *handle)
426{
427	struct tegra_bo *bo;
428	int err;
429
430	bo = tegra_bo_create(drm, size, flags);
431	if (IS_ERR(bo))
432		return bo;
433
434	err = drm_gem_handle_create(file, &bo->gem, handle);
435	if (err) {
436		tegra_bo_free_object(&bo->gem);
437		return ERR_PTR(err);
438	}
439
440	drm_gem_object_put(&bo->gem);
441
442	return bo;
443}
444
445static struct tegra_bo *tegra_bo_import(struct drm_device *drm,
446					struct dma_buf *buf)
447{
448	struct tegra_drm *tegra = drm->dev_private;
449	struct dma_buf_attachment *attach;
450	struct tegra_bo *bo;
451	int err;
452
453	bo = tegra_bo_alloc_object(drm, buf->size);
454	if (IS_ERR(bo))
455		return bo;
456
457	attach = dma_buf_attach(buf, drm->dev);
458	if (IS_ERR(attach)) {
459		err = PTR_ERR(attach);
460		goto free;
461	}
462
463	get_dma_buf(buf);
464
465	bo->sgt = dma_buf_map_attachment_unlocked(attach, DMA_TO_DEVICE);
466	if (IS_ERR(bo->sgt)) {
467		err = PTR_ERR(bo->sgt);
468		goto detach;
469	}
470
471	if (tegra->domain) {
472		err = tegra_bo_iommu_map(tegra, bo);
473		if (err < 0)
474			goto detach;
475	}
476
477	bo->gem.import_attach = attach;
478
479	return bo;
480
481detach:
482	if (!IS_ERR_OR_NULL(bo->sgt))
483		dma_buf_unmap_attachment_unlocked(attach, bo->sgt, DMA_TO_DEVICE);
484
485	dma_buf_detach(buf, attach);
486	dma_buf_put(buf);
487free:
488	drm_gem_object_release(&bo->gem);
489	kfree(bo);
490	return ERR_PTR(err);
491}
492
493void tegra_bo_free_object(struct drm_gem_object *gem)
494{
495	struct tegra_drm *tegra = gem->dev->dev_private;
496	struct host1x_bo_mapping *mapping, *tmp;
497	struct tegra_bo *bo = to_tegra_bo(gem);
498
499	/* remove all mappings of this buffer object from any caches */
500	list_for_each_entry_safe(mapping, tmp, &bo->base.mappings, list) {
501		if (mapping->cache)
502			host1x_bo_unpin(mapping);
503		else
504			dev_err(gem->dev->dev, "mapping %p stale for device %s\n", mapping,
505				dev_name(mapping->dev));
506	}
507
508	if (tegra->domain)
509		tegra_bo_iommu_unmap(tegra, bo);
510
511	if (gem->import_attach) {
512		dma_buf_unmap_attachment_unlocked(gem->import_attach, bo->sgt,
513						  DMA_TO_DEVICE);
514		drm_prime_gem_destroy(gem, NULL);
515	} else {
516		tegra_bo_free(gem->dev, bo);
517	}
518
519	drm_gem_object_release(gem);
520	kfree(bo);
521}
522
523int tegra_bo_dumb_create(struct drm_file *file, struct drm_device *drm,
524			 struct drm_mode_create_dumb *args)
525{
526	unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
527	struct tegra_drm *tegra = drm->dev_private;
528	struct tegra_bo *bo;
529
530	args->pitch = round_up(min_pitch, tegra->pitch_align);
531	args->size = args->pitch * args->height;
532
533	bo = tegra_bo_create_with_handle(file, drm, args->size, 0,
534					 &args->handle);
535	if (IS_ERR(bo))
536		return PTR_ERR(bo);
537
538	return 0;
539}
540
541static vm_fault_t tegra_bo_fault(struct vm_fault *vmf)
542{
543	struct vm_area_struct *vma = vmf->vma;
544	struct drm_gem_object *gem = vma->vm_private_data;
545	struct tegra_bo *bo = to_tegra_bo(gem);
546	struct page *page;
547	pgoff_t offset;
548
549	if (!bo->pages)
550		return VM_FAULT_SIGBUS;
551
552	offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
553	page = bo->pages[offset];
554
555	return vmf_insert_page(vma, vmf->address, page);
556}
557
558const struct vm_operations_struct tegra_bo_vm_ops = {
559	.fault = tegra_bo_fault,
560	.open = drm_gem_vm_open,
561	.close = drm_gem_vm_close,
562};
563
564int __tegra_gem_mmap(struct drm_gem_object *gem, struct vm_area_struct *vma)
565{
566	struct tegra_bo *bo = to_tegra_bo(gem);
567
568	if (!bo->pages) {
569		unsigned long vm_pgoff = vma->vm_pgoff;
570		int err;
571
572		/*
573		 * Clear the VM_PFNMAP flag that was set by drm_gem_mmap(),
574		 * and set the vm_pgoff (used as a fake buffer offset by DRM)
575		 * to 0 as we want to map the whole buffer.
576		 */
577		vma->vm_flags &= ~VM_PFNMAP;
578		vma->vm_pgoff = 0;
579
580		err = dma_mmap_wc(gem->dev->dev, vma, bo->vaddr, bo->iova,
581				  gem->size);
582		if (err < 0) {
583			drm_gem_vm_close(vma);
584			return err;
585		}
586
587		vma->vm_pgoff = vm_pgoff;
588	} else {
589		pgprot_t prot = vm_get_page_prot(vma->vm_flags);
590
591		vma->vm_flags |= VM_MIXEDMAP;
592		vma->vm_flags &= ~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	dma_resv_assert_held(buf->resv);
698
699	err = drm_gem_mmap_obj(gem, gem->size, vma);
700	if (err < 0)
701		return err;
702
703	return __tegra_gem_mmap(gem, vma);
704}
705
706static int tegra_gem_prime_vmap(struct dma_buf *buf, struct iosys_map *map)
707{
708	struct drm_gem_object *gem = buf->priv;
709	struct tegra_bo *bo = to_tegra_bo(gem);
710	void *vaddr;
711
712	vaddr = tegra_bo_mmap(&bo->base);
713	if (IS_ERR(vaddr))
714		return PTR_ERR(vaddr);
715
716	iosys_map_set_vaddr(map, vaddr);
717
718	return 0;
719}
720
721static void tegra_gem_prime_vunmap(struct dma_buf *buf, struct iosys_map *map)
722{
723	struct drm_gem_object *gem = buf->priv;
724	struct tegra_bo *bo = to_tegra_bo(gem);
725
726	tegra_bo_munmap(&bo->base, map->vaddr);
727}
728
729static const struct dma_buf_ops tegra_gem_prime_dmabuf_ops = {
730	.map_dma_buf = tegra_gem_prime_map_dma_buf,
731	.unmap_dma_buf = tegra_gem_prime_unmap_dma_buf,
732	.release = tegra_gem_prime_release,
733	.begin_cpu_access = tegra_gem_prime_begin_cpu_access,
734	.end_cpu_access = tegra_gem_prime_end_cpu_access,
735	.mmap = tegra_gem_prime_mmap,
736	.vmap = tegra_gem_prime_vmap,
737	.vunmap = tegra_gem_prime_vunmap,
738};
739
740struct dma_buf *tegra_gem_prime_export(struct drm_gem_object *gem,
741				       int flags)
742{
743	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
744
745	exp_info.exp_name = KBUILD_MODNAME;
746	exp_info.owner = gem->dev->driver->fops->owner;
747	exp_info.ops = &tegra_gem_prime_dmabuf_ops;
748	exp_info.size = gem->size;
749	exp_info.flags = flags;
750	exp_info.priv = gem;
751
752	return drm_gem_dmabuf_export(gem->dev, &exp_info);
753}
754
755struct drm_gem_object *tegra_gem_prime_import(struct drm_device *drm,
756					      struct dma_buf *buf)
757{
758	struct tegra_bo *bo;
759
760	if (buf->ops == &tegra_gem_prime_dmabuf_ops) {
761		struct drm_gem_object *gem = buf->priv;
762
763		if (gem->dev == drm) {
764			drm_gem_object_get(gem);
765			return gem;
766		}
767	}
768
769	bo = tegra_bo_import(drm, buf);
770	if (IS_ERR(bo))
771		return ERR_CAST(bo);
772
773	return &bo->gem;
774}
775
776struct host1x_bo *tegra_gem_lookup(struct drm_file *file, u32 handle)
777{
778	struct drm_gem_object *gem;
779	struct tegra_bo *bo;
780
781	gem = drm_gem_object_lookup(file, handle);
782	if (!gem)
783		return NULL;
784
785	bo = to_tegra_bo(gem);
786	return &bo->base;
787}
v5.14.15
  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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 23static 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? */
 31static 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
 53static 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
 
 
119free:
120	kfree(sgt);
 
121	return ERR_PTR(err);
122}
123
124static 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
132static 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
149static 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
162static 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
171static 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
180static 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
215remove:
216	drm_mm_remove_node(bo->mm);
217unlock:
218	mutex_unlock(&tegra->mm_lock);
219	kfree(bo->mm);
220	return err;
221}
222
223static 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
238static 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
244static 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
269release:
270	drm_gem_object_release(&bo->gem);
271free:
272	kfree(bo);
273	return ERR_PTR(err);
274}
275
276static 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
288static 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
310free_sgt:
311	sg_free_table(bo->sgt);
312	kfree(bo->sgt);
313put_pages:
314	drm_gem_put_pages(&bo->gem, bo->pages, false, false);
315	return err;
316}
317
318static 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
349struct 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
371release:
372	drm_gem_object_release(&bo->gem);
373	kfree(bo);
374	return ERR_PTR(err);
375}
376
377struct 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
401static 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
437detach:
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);
443free:
444	drm_gem_object_release(&bo->gem);
445	kfree(bo);
446	return ERR_PTR(err);
447}
448
449void 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
469int 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
487static 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
504const 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
510int __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
546int 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
560static struct sg_table *
561tegra_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
587free:
588	sg_free_table(sgt);
589	kfree(sgt);
590	return NULL;
591}
592
593static 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
607static void tegra_gem_prime_release(struct dma_buf *buf)
608{
609	drm_gem_dmabuf_release(buf);
610}
611
612static 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
625static 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
638static 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
650static 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
660static void tegra_gem_prime_vunmap(struct dma_buf *buf, struct dma_buf_map *map)
661{
 
 
 
 
662}
663
664static 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
675struct 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
690struct 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}