xref: /openbmc/linux/drivers/gpu/drm/tegra/submit.c (revision 65844828)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2020 NVIDIA Corporation */
3 
4 #include <linux/dma-fence-array.h>
5 #include <linux/dma-mapping.h>
6 #include <linux/file.h>
7 #include <linux/host1x.h>
8 #include <linux/iommu.h>
9 #include <linux/kref.h>
10 #include <linux/list.h>
11 #include <linux/nospec.h>
12 #include <linux/pm_runtime.h>
13 #include <linux/scatterlist.h>
14 #include <linux/slab.h>
15 #include <linux/sync_file.h>
16 
17 #include <drm/drm_drv.h>
18 #include <drm/drm_file.h>
19 #include <drm/drm_syncobj.h>
20 
21 #include "drm.h"
22 #include "gem.h"
23 #include "submit.h"
24 #include "uapi.h"
25 
26 #define SUBMIT_ERR(context, fmt, ...) \
27 	dev_err_ratelimited(context->client->base.dev, \
28 		"%s: job submission failed: " fmt "\n", \
29 		current->comm, ##__VA_ARGS__)
30 
31 struct gather_bo {
32 	struct host1x_bo base;
33 
34 	struct kref ref;
35 
36 	struct device *dev;
37 	u32 *gather_data;
38 	dma_addr_t gather_data_dma;
39 	size_t gather_data_words;
40 };
41 
42 static struct host1x_bo *gather_bo_get(struct host1x_bo *host_bo)
43 {
44 	struct gather_bo *bo = container_of(host_bo, struct gather_bo, base);
45 
46 	kref_get(&bo->ref);
47 
48 	return host_bo;
49 }
50 
51 static void gather_bo_release(struct kref *ref)
52 {
53 	struct gather_bo *bo = container_of(ref, struct gather_bo, ref);
54 
55 	dma_free_attrs(bo->dev, bo->gather_data_words * 4, bo->gather_data, bo->gather_data_dma,
56 		       0);
57 	kfree(bo);
58 }
59 
60 static void gather_bo_put(struct host1x_bo *host_bo)
61 {
62 	struct gather_bo *bo = container_of(host_bo, struct gather_bo, base);
63 
64 	kref_put(&bo->ref, gather_bo_release);
65 }
66 
67 static struct host1x_bo_mapping *
68 gather_bo_pin(struct device *dev, struct host1x_bo *bo, enum dma_data_direction direction)
69 {
70 	struct gather_bo *gather = container_of(bo, struct gather_bo, base);
71 	struct host1x_bo_mapping *map;
72 	int err;
73 
74 	map = kzalloc(sizeof(*map), GFP_KERNEL);
75 	if (!map)
76 		return ERR_PTR(-ENOMEM);
77 
78 	kref_init(&map->ref);
79 	map->bo = host1x_bo_get(bo);
80 	map->direction = direction;
81 	map->dev = dev;
82 
83 	map->sgt = kzalloc(sizeof(*map->sgt), GFP_KERNEL);
84 	if (!map->sgt) {
85 		err = -ENOMEM;
86 		goto free;
87 	}
88 
89 	err = dma_get_sgtable(gather->dev, map->sgt, gather->gather_data, gather->gather_data_dma,
90 			      gather->gather_data_words * 4);
91 	if (err)
92 		goto free_sgt;
93 
94 	err = dma_map_sgtable(dev, map->sgt, direction, 0);
95 	if (err)
96 		goto free_sgt;
97 
98 	map->phys = sg_dma_address(map->sgt->sgl);
99 	map->size = gather->gather_data_words * 4;
100 	map->chunks = err;
101 
102 	return map;
103 
104 free_sgt:
105 	sg_free_table(map->sgt);
106 	kfree(map->sgt);
107 free:
108 	kfree(map);
109 	return ERR_PTR(err);
110 }
111 
112 static void gather_bo_unpin(struct host1x_bo_mapping *map)
113 {
114 	if (!map)
115 		return;
116 
117 	dma_unmap_sgtable(map->dev, map->sgt, map->direction, 0);
118 	sg_free_table(map->sgt);
119 	kfree(map->sgt);
120 	host1x_bo_put(map->bo);
121 
122 	kfree(map);
123 }
124 
125 static void *gather_bo_mmap(struct host1x_bo *host_bo)
126 {
127 	struct gather_bo *bo = container_of(host_bo, struct gather_bo, base);
128 
129 	return bo->gather_data;
130 }
131 
132 static void gather_bo_munmap(struct host1x_bo *host_bo, void *addr)
133 {
134 }
135 
136 static const struct host1x_bo_ops gather_bo_ops = {
137 	.get = gather_bo_get,
138 	.put = gather_bo_put,
139 	.pin = gather_bo_pin,
140 	.unpin = gather_bo_unpin,
141 	.mmap = gather_bo_mmap,
142 	.munmap = gather_bo_munmap,
143 };
144 
145 static struct tegra_drm_mapping *
146 tegra_drm_mapping_get(struct tegra_drm_context *context, u32 id)
147 {
148 	struct tegra_drm_mapping *mapping;
149 
150 	xa_lock(&context->mappings);
151 
152 	mapping = xa_load(&context->mappings, id);
153 	if (mapping)
154 		kref_get(&mapping->ref);
155 
156 	xa_unlock(&context->mappings);
157 
158 	return mapping;
159 }
160 
161 static void *alloc_copy_user_array(void __user *from, size_t count, size_t size)
162 {
163 	size_t copy_len;
164 	void *data;
165 
166 	if (check_mul_overflow(count, size, &copy_len))
167 		return ERR_PTR(-EINVAL);
168 
169 	if (copy_len > 0x4000)
170 		return ERR_PTR(-E2BIG);
171 
172 	data = vmemdup_user(from, copy_len);
173 	if (IS_ERR(data))
174 		return ERR_CAST(data);
175 
176 	return data;
177 }
178 
179 static int submit_copy_gather_data(struct gather_bo **pbo, struct device *dev,
180 				   struct tegra_drm_context *context,
181 				   struct drm_tegra_channel_submit *args)
182 {
183 	struct gather_bo *bo;
184 	size_t copy_len;
185 
186 	if (args->gather_data_words == 0) {
187 		SUBMIT_ERR(context, "gather_data_words cannot be zero");
188 		return -EINVAL;
189 	}
190 
191 	if (check_mul_overflow((size_t)args->gather_data_words, (size_t)4, &copy_len)) {
192 		SUBMIT_ERR(context, "gather_data_words is too large");
193 		return -EINVAL;
194 	}
195 
196 	bo = kzalloc(sizeof(*bo), GFP_KERNEL);
197 	if (!bo) {
198 		SUBMIT_ERR(context, "failed to allocate memory for bo info");
199 		return -ENOMEM;
200 	}
201 
202 	host1x_bo_init(&bo->base, &gather_bo_ops);
203 	kref_init(&bo->ref);
204 	bo->dev = dev;
205 
206 	bo->gather_data = dma_alloc_attrs(dev, copy_len, &bo->gather_data_dma,
207 					  GFP_KERNEL | __GFP_NOWARN, 0);
208 	if (!bo->gather_data) {
209 		SUBMIT_ERR(context, "failed to allocate memory for gather data");
210 		kfree(bo);
211 		return -ENOMEM;
212 	}
213 
214 	if (copy_from_user(bo->gather_data, u64_to_user_ptr(args->gather_data_ptr), copy_len)) {
215 		SUBMIT_ERR(context, "failed to copy gather data from userspace");
216 		dma_free_attrs(dev, copy_len, bo->gather_data, bo->gather_data_dma, 0);
217 		kfree(bo);
218 		return -EFAULT;
219 	}
220 
221 	bo->gather_data_words = args->gather_data_words;
222 
223 	*pbo = bo;
224 
225 	return 0;
226 }
227 
228 static int submit_write_reloc(struct tegra_drm_context *context, struct gather_bo *bo,
229 			      struct drm_tegra_submit_buf *buf, struct tegra_drm_mapping *mapping)
230 {
231 	/* TODO check that target_offset is within bounds */
232 	dma_addr_t iova = mapping->iova + buf->reloc.target_offset;
233 	u32 written_ptr;
234 
235 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
236 	if (buf->flags & DRM_TEGRA_SUBMIT_RELOC_SECTOR_LAYOUT)
237 		iova |= BIT_ULL(39);
238 #endif
239 
240 	written_ptr = iova >> buf->reloc.shift;
241 
242 	if (buf->reloc.gather_offset_words >= bo->gather_data_words) {
243 		SUBMIT_ERR(context,
244 			   "relocation has too large gather offset (%u vs gather length %zu)",
245 			   buf->reloc.gather_offset_words, bo->gather_data_words);
246 		return -EINVAL;
247 	}
248 
249 	buf->reloc.gather_offset_words = array_index_nospec(buf->reloc.gather_offset_words,
250 							    bo->gather_data_words);
251 
252 	bo->gather_data[buf->reloc.gather_offset_words] = written_ptr;
253 
254 	return 0;
255 }
256 
257 static int submit_process_bufs(struct tegra_drm_context *context, struct gather_bo *bo,
258 			       struct drm_tegra_channel_submit *args,
259 			       struct tegra_drm_submit_data *job_data)
260 {
261 	struct tegra_drm_used_mapping *mappings;
262 	struct drm_tegra_submit_buf *bufs;
263 	int err;
264 	u32 i;
265 
266 	bufs = alloc_copy_user_array(u64_to_user_ptr(args->bufs_ptr), args->num_bufs,
267 				     sizeof(*bufs));
268 	if (IS_ERR(bufs)) {
269 		SUBMIT_ERR(context, "failed to copy bufs array from userspace");
270 		return PTR_ERR(bufs);
271 	}
272 
273 	mappings = kcalloc(args->num_bufs, sizeof(*mappings), GFP_KERNEL);
274 	if (!mappings) {
275 		SUBMIT_ERR(context, "failed to allocate memory for mapping info");
276 		err = -ENOMEM;
277 		goto done;
278 	}
279 
280 	for (i = 0; i < args->num_bufs; i++) {
281 		struct drm_tegra_submit_buf *buf = &bufs[i];
282 		struct tegra_drm_mapping *mapping;
283 
284 		if (buf->flags & ~DRM_TEGRA_SUBMIT_RELOC_SECTOR_LAYOUT) {
285 			SUBMIT_ERR(context, "invalid flag specified for buffer");
286 			err = -EINVAL;
287 			goto drop_refs;
288 		}
289 
290 		mapping = tegra_drm_mapping_get(context, buf->mapping);
291 		if (!mapping) {
292 			SUBMIT_ERR(context, "invalid mapping ID '%u' for buffer", buf->mapping);
293 			err = -EINVAL;
294 			goto drop_refs;
295 		}
296 
297 		err = submit_write_reloc(context, bo, buf, mapping);
298 		if (err) {
299 			tegra_drm_mapping_put(mapping);
300 			goto drop_refs;
301 		}
302 
303 		mappings[i].mapping = mapping;
304 		mappings[i].flags = buf->flags;
305 	}
306 
307 	job_data->used_mappings = mappings;
308 	job_data->num_used_mappings = i;
309 
310 	err = 0;
311 
312 	goto done;
313 
314 drop_refs:
315 	while (i--)
316 		tegra_drm_mapping_put(mappings[i].mapping);
317 
318 	kfree(mappings);
319 	job_data->used_mappings = NULL;
320 
321 done:
322 	kvfree(bufs);
323 
324 	return err;
325 }
326 
327 static int submit_get_syncpt(struct tegra_drm_context *context, struct host1x_job *job,
328 			     struct xarray *syncpoints, struct drm_tegra_channel_submit *args)
329 {
330 	struct host1x_syncpt *sp;
331 
332 	if (args->syncpt.flags) {
333 		SUBMIT_ERR(context, "invalid flag specified for syncpt");
334 		return -EINVAL;
335 	}
336 
337 	/* Syncpt ref will be dropped on job release */
338 	sp = xa_load(syncpoints, args->syncpt.id);
339 	if (!sp) {
340 		SUBMIT_ERR(context, "syncpoint specified in syncpt was not allocated");
341 		return -EINVAL;
342 	}
343 
344 	job->syncpt = host1x_syncpt_get(sp);
345 	job->syncpt_incrs = args->syncpt.increments;
346 
347 	return 0;
348 }
349 
350 static int submit_job_add_gather(struct host1x_job *job, struct tegra_drm_context *context,
351 				 struct drm_tegra_submit_cmd_gather_uptr *cmd,
352 				 struct gather_bo *bo, u32 *offset,
353 				 struct tegra_drm_submit_data *job_data,
354 				 u32 *class)
355 {
356 	u32 next_offset;
357 
358 	if (cmd->reserved[0] || cmd->reserved[1] || cmd->reserved[2]) {
359 		SUBMIT_ERR(context, "non-zero reserved field in GATHER_UPTR command");
360 		return -EINVAL;
361 	}
362 
363 	/* Check for maximum gather size */
364 	if (cmd->words > 16383) {
365 		SUBMIT_ERR(context, "too many words in GATHER_UPTR command");
366 		return -EINVAL;
367 	}
368 
369 	if (check_add_overflow(*offset, cmd->words, &next_offset)) {
370 		SUBMIT_ERR(context, "too many total words in job");
371 		return -EINVAL;
372 	}
373 
374 	if (next_offset > bo->gather_data_words) {
375 		SUBMIT_ERR(context, "GATHER_UPTR command overflows gather data");
376 		return -EINVAL;
377 	}
378 
379 	if (tegra_drm_fw_validate(context->client, bo->gather_data, *offset,
380 				  cmd->words, job_data, class)) {
381 		SUBMIT_ERR(context, "job was rejected by firewall");
382 		return -EINVAL;
383 	}
384 
385 	host1x_job_add_gather(job, &bo->base, cmd->words, *offset * 4);
386 
387 	*offset = next_offset;
388 
389 	return 0;
390 }
391 
392 static struct host1x_job *
393 submit_create_job(struct tegra_drm_context *context, struct gather_bo *bo,
394 		  struct drm_tegra_channel_submit *args, struct tegra_drm_submit_data *job_data,
395 		  struct xarray *syncpoints)
396 {
397 	struct drm_tegra_submit_cmd *cmds;
398 	u32 i, gather_offset = 0, class;
399 	struct host1x_job *job;
400 	int err;
401 
402 	/* Set initial class for firewall. */
403 	class = context->client->base.class;
404 
405 	cmds = alloc_copy_user_array(u64_to_user_ptr(args->cmds_ptr), args->num_cmds,
406 				     sizeof(*cmds));
407 	if (IS_ERR(cmds)) {
408 		SUBMIT_ERR(context, "failed to copy cmds array from userspace");
409 		return ERR_CAST(cmds);
410 	}
411 
412 	job = host1x_job_alloc(context->channel, args->num_cmds, 0, true);
413 	if (!job) {
414 		SUBMIT_ERR(context, "failed to allocate memory for job");
415 		job = ERR_PTR(-ENOMEM);
416 		goto done;
417 	}
418 
419 	err = submit_get_syncpt(context, job, syncpoints, args);
420 	if (err < 0)
421 		goto free_job;
422 
423 	job->client = &context->client->base;
424 	job->class = context->client->base.class;
425 	job->serialize = true;
426 
427 	for (i = 0; i < args->num_cmds; i++) {
428 		struct drm_tegra_submit_cmd *cmd = &cmds[i];
429 
430 		if (cmd->flags) {
431 			SUBMIT_ERR(context, "unknown flags given for cmd");
432 			err = -EINVAL;
433 			goto free_job;
434 		}
435 
436 		if (cmd->type == DRM_TEGRA_SUBMIT_CMD_GATHER_UPTR) {
437 			err = submit_job_add_gather(job, context, &cmd->gather_uptr, bo,
438 						    &gather_offset, job_data, &class);
439 			if (err)
440 				goto free_job;
441 		} else if (cmd->type == DRM_TEGRA_SUBMIT_CMD_WAIT_SYNCPT) {
442 			if (cmd->wait_syncpt.reserved[0] || cmd->wait_syncpt.reserved[1]) {
443 				SUBMIT_ERR(context, "non-zero reserved value");
444 				err = -EINVAL;
445 				goto free_job;
446 			}
447 
448 			host1x_job_add_wait(job, cmd->wait_syncpt.id, cmd->wait_syncpt.value,
449 					    false, class);
450 		} else if (cmd->type == DRM_TEGRA_SUBMIT_CMD_WAIT_SYNCPT_RELATIVE) {
451 			if (cmd->wait_syncpt.reserved[0] || cmd->wait_syncpt.reserved[1]) {
452 				SUBMIT_ERR(context, "non-zero reserved value");
453 				err = -EINVAL;
454 				goto free_job;
455 			}
456 
457 			if (cmd->wait_syncpt.id != args->syncpt.id) {
458 				SUBMIT_ERR(context, "syncpoint ID in CMD_WAIT_SYNCPT_RELATIVE is not used by the job");
459 				err = -EINVAL;
460 				goto free_job;
461 			}
462 
463 			host1x_job_add_wait(job, cmd->wait_syncpt.id, cmd->wait_syncpt.value,
464 					    true, class);
465 		} else {
466 			SUBMIT_ERR(context, "unknown cmd type");
467 			err = -EINVAL;
468 			goto free_job;
469 		}
470 	}
471 
472 	if (gather_offset == 0) {
473 		SUBMIT_ERR(context, "job must have at least one gather");
474 		err = -EINVAL;
475 		goto free_job;
476 	}
477 
478 	goto done;
479 
480 free_job:
481 	host1x_job_put(job);
482 	job = ERR_PTR(err);
483 
484 done:
485 	kvfree(cmds);
486 
487 	return job;
488 }
489 
490 static void release_job(struct host1x_job *job)
491 {
492 	struct tegra_drm_client *client = container_of(job->client, struct tegra_drm_client, base);
493 	struct tegra_drm_submit_data *job_data = job->user_data;
494 	u32 i;
495 
496 	if (job->memory_context)
497 		host1x_memory_context_put(job->memory_context);
498 
499 	for (i = 0; i < job_data->num_used_mappings; i++)
500 		tegra_drm_mapping_put(job_data->used_mappings[i].mapping);
501 
502 	kfree(job_data->used_mappings);
503 	kfree(job_data);
504 
505 	pm_runtime_mark_last_busy(client->base.dev);
506 	pm_runtime_put_autosuspend(client->base.dev);
507 }
508 
509 int tegra_drm_ioctl_channel_submit(struct drm_device *drm, void *data,
510 				   struct drm_file *file)
511 {
512 	struct tegra_drm_file *fpriv = file->driver_priv;
513 	struct drm_tegra_channel_submit *args = data;
514 	struct tegra_drm_submit_data *job_data;
515 	struct drm_syncobj *syncobj = NULL;
516 	struct tegra_drm_context *context;
517 	struct host1x_job *job;
518 	struct gather_bo *bo;
519 	u32 i;
520 	int err;
521 
522 	mutex_lock(&fpriv->lock);
523 
524 	context = xa_load(&fpriv->contexts, args->context);
525 	if (!context) {
526 		mutex_unlock(&fpriv->lock);
527 		pr_err_ratelimited("%s: %s: invalid channel context '%#x'", __func__,
528 				   current->comm, args->context);
529 		return -EINVAL;
530 	}
531 
532 	if (args->syncobj_in) {
533 		struct dma_fence *fence;
534 
535 		err = drm_syncobj_find_fence(file, args->syncobj_in, 0, 0, &fence);
536 		if (err) {
537 			SUBMIT_ERR(context, "invalid syncobj_in '%#x'", args->syncobj_in);
538 			goto unlock;
539 		}
540 
541 		err = dma_fence_wait_timeout(fence, true, msecs_to_jiffies(10000));
542 		dma_fence_put(fence);
543 		if (err) {
544 			SUBMIT_ERR(context, "wait for syncobj_in timed out");
545 			goto unlock;
546 		}
547 	}
548 
549 	if (args->syncobj_out) {
550 		syncobj = drm_syncobj_find(file, args->syncobj_out);
551 		if (!syncobj) {
552 			SUBMIT_ERR(context, "invalid syncobj_out '%#x'", args->syncobj_out);
553 			err = -ENOENT;
554 			goto unlock;
555 		}
556 	}
557 
558 	/* Allocate gather BO and copy gather words in. */
559 	err = submit_copy_gather_data(&bo, drm->dev, context, args);
560 	if (err)
561 		goto unlock;
562 
563 	job_data = kzalloc(sizeof(*job_data), GFP_KERNEL);
564 	if (!job_data) {
565 		SUBMIT_ERR(context, "failed to allocate memory for job data");
566 		err = -ENOMEM;
567 		goto put_bo;
568 	}
569 
570 	/* Get data buffer mappings and do relocation patching. */
571 	err = submit_process_bufs(context, bo, args, job_data);
572 	if (err)
573 		goto free_job_data;
574 
575 	/* Allocate host1x_job and add gathers and waits to it. */
576 	job = submit_create_job(context, bo, args, job_data, &fpriv->syncpoints);
577 	if (IS_ERR(job)) {
578 		err = PTR_ERR(job);
579 		goto free_job_data;
580 	}
581 
582 	/* Map gather data for Host1x. */
583 	err = host1x_job_pin(job, context->client->base.dev);
584 	if (err) {
585 		SUBMIT_ERR(context, "failed to pin job: %d", err);
586 		goto put_job;
587 	}
588 
589 	if (context->client->ops->get_streamid_offset) {
590 		err = context->client->ops->get_streamid_offset(
591 			context->client, &job->engine_streamid_offset);
592 		if (err) {
593 			SUBMIT_ERR(context, "failed to get streamid offset: %d", err);
594 			goto unpin_job;
595 		}
596 	}
597 
598 	if (context->memory_context && context->client->ops->can_use_memory_ctx) {
599 		bool supported;
600 
601 		err = context->client->ops->can_use_memory_ctx(context->client, &supported);
602 		if (err) {
603 			SUBMIT_ERR(context, "failed to detect if engine can use memory context: %d", err);
604 			goto unpin_job;
605 		}
606 
607 		if (supported) {
608 			job->memory_context = context->memory_context;
609 			host1x_memory_context_get(job->memory_context);
610 		}
611 	} else if (context->client->ops->get_streamid_offset) {
612 #ifdef CONFIG_IOMMU_API
613 		struct iommu_fwspec *spec;
614 
615 		/*
616 		 * Job submission will need to temporarily change stream ID,
617 		 * so need to tell it what to change it back to.
618 		 */
619 		spec = dev_iommu_fwspec_get(context->client->base.dev);
620 		if (spec && spec->num_ids > 0)
621 			job->engine_fallback_streamid = spec->ids[0] & 0xffff;
622 		else
623 			job->engine_fallback_streamid = 0x7f;
624 #else
625 		job->engine_fallback_streamid = 0x7f;
626 #endif
627 	}
628 
629 	/* Boot engine. */
630 	err = pm_runtime_resume_and_get(context->client->base.dev);
631 	if (err < 0) {
632 		SUBMIT_ERR(context, "could not power up engine: %d", err);
633 		goto put_memory_context;
634 	}
635 
636 	job->user_data = job_data;
637 	job->release = release_job;
638 	job->timeout = 10000;
639 
640 	/*
641 	 * job_data is now part of job reference counting, so don't release
642 	 * it from here.
643 	 */
644 	job_data = NULL;
645 
646 	/* Submit job to hardware. */
647 	err = host1x_job_submit(job);
648 	if (err) {
649 		SUBMIT_ERR(context, "host1x job submission failed: %d", err);
650 		goto unpin_job;
651 	}
652 
653 	/* Return postfences to userspace and add fences to DMA reservations. */
654 	args->syncpt.value = job->syncpt_end;
655 
656 	if (syncobj) {
657 		struct dma_fence *fence = host1x_fence_create(job->syncpt, job->syncpt_end);
658 		if (IS_ERR(fence)) {
659 			err = PTR_ERR(fence);
660 			SUBMIT_ERR(context, "failed to create postfence: %d", err);
661 		}
662 
663 		drm_syncobj_replace_fence(syncobj, fence);
664 	}
665 
666 	goto put_job;
667 
668 put_memory_context:
669 	if (job->memory_context)
670 		host1x_memory_context_put(job->memory_context);
671 unpin_job:
672 	host1x_job_unpin(job);
673 put_job:
674 	host1x_job_put(job);
675 free_job_data:
676 	if (job_data && job_data->used_mappings) {
677 		for (i = 0; i < job_data->num_used_mappings; i++)
678 			tegra_drm_mapping_put(job_data->used_mappings[i].mapping);
679 
680 		kfree(job_data->used_mappings);
681 	}
682 
683 	if (job_data)
684 		kfree(job_data);
685 put_bo:
686 	gather_bo_put(&bo->base);
687 unlock:
688 	if (syncobj)
689 		drm_syncobj_put(syncobj);
690 
691 	mutex_unlock(&fpriv->lock);
692 	return err;
693 }
694