xref: /openbmc/linux/drivers/gpu/drm/i915/gvt/dmabuf.c (revision 9a29f5fc)
1 /*
2  * Copyright 2017 Intel Corporation. All rights reserved.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21  * DEALINGS IN THE SOFTWARE.
22  *
23  * Authors:
24  *    Zhiyuan Lv <zhiyuan.lv@intel.com>
25  *
26  * Contributors:
27  *    Xiaoguang Chen
28  *    Tina Zhang <tina.zhang@intel.com>
29  */
30 
31 #include <linux/dma-buf.h>
32 #include <linux/mdev.h>
33 
34 #include <drm/drm_fourcc.h>
35 #include <drm/drm_plane.h>
36 
37 #include "gem/i915_gem_dmabuf.h"
38 
39 #include "i915_drv.h"
40 #include "i915_reg.h"
41 #include "gvt.h"
42 
43 #define GEN8_DECODE_PTE(pte) (pte & GENMASK_ULL(63, 12))
44 
45 static int vgpu_gem_get_pages(
46 		struct drm_i915_gem_object *obj)
47 {
48 	struct drm_i915_private *dev_priv = to_i915(obj->base.dev);
49 	struct intel_vgpu *vgpu;
50 	struct sg_table *st;
51 	struct scatterlist *sg;
52 	int i, j, ret;
53 	gen8_pte_t __iomem *gtt_entries;
54 	struct intel_vgpu_fb_info *fb_info;
55 	u32 page_num;
56 
57 	fb_info = (struct intel_vgpu_fb_info *)obj->gvt_info;
58 	if (drm_WARN_ON(&dev_priv->drm, !fb_info))
59 		return -ENODEV;
60 
61 	vgpu = fb_info->obj->vgpu;
62 	if (drm_WARN_ON(&dev_priv->drm, !vgpu))
63 		return -ENODEV;
64 
65 	st = kmalloc(sizeof(*st), GFP_KERNEL);
66 	if (unlikely(!st))
67 		return -ENOMEM;
68 
69 	page_num = obj->base.size >> PAGE_SHIFT;
70 	ret = sg_alloc_table(st, page_num, GFP_KERNEL);
71 	if (ret) {
72 		kfree(st);
73 		return ret;
74 	}
75 	gtt_entries = (gen8_pte_t __iomem *)to_gt(dev_priv)->ggtt->gsm +
76 		(fb_info->start >> PAGE_SHIFT);
77 	for_each_sg(st->sgl, sg, page_num, i) {
78 		dma_addr_t dma_addr =
79 			GEN8_DECODE_PTE(readq(&gtt_entries[i]));
80 		if (intel_gvt_dma_pin_guest_page(vgpu, dma_addr)) {
81 			ret = -EINVAL;
82 			goto out;
83 		}
84 
85 		sg->offset = 0;
86 		sg->length = PAGE_SIZE;
87 		sg_dma_len(sg) = PAGE_SIZE;
88 		sg_dma_address(sg) = dma_addr;
89 	}
90 
91 	__i915_gem_object_set_pages(obj, st, PAGE_SIZE);
92 out:
93 	if (ret) {
94 		dma_addr_t dma_addr;
95 
96 		for_each_sg(st->sgl, sg, i, j) {
97 			dma_addr = sg_dma_address(sg);
98 			if (dma_addr)
99 				intel_gvt_dma_unmap_guest_page(vgpu, dma_addr);
100 		}
101 		sg_free_table(st);
102 		kfree(st);
103 	}
104 
105 	return ret;
106 
107 }
108 
109 static void vgpu_gem_put_pages(struct drm_i915_gem_object *obj,
110 		struct sg_table *pages)
111 {
112 	struct scatterlist *sg;
113 
114 	if (obj->base.dma_buf) {
115 		struct intel_vgpu_fb_info *fb_info = obj->gvt_info;
116 		struct intel_vgpu_dmabuf_obj *obj = fb_info->obj;
117 		struct intel_vgpu *vgpu = obj->vgpu;
118 		int i;
119 
120 		for_each_sg(pages->sgl, sg, fb_info->size, i)
121 			intel_gvt_dma_unmap_guest_page(vgpu,
122 					       sg_dma_address(sg));
123 	}
124 
125 	sg_free_table(pages);
126 	kfree(pages);
127 }
128 
129 static void dmabuf_gem_object_free(struct kref *kref)
130 {
131 	struct intel_vgpu_dmabuf_obj *obj =
132 		container_of(kref, struct intel_vgpu_dmabuf_obj, kref);
133 	struct intel_vgpu *vgpu = obj->vgpu;
134 	struct list_head *pos;
135 	struct intel_vgpu_dmabuf_obj *dmabuf_obj;
136 
137 	if (vgpu && vgpu->active && !list_empty(&vgpu->dmabuf_obj_list_head)) {
138 		list_for_each(pos, &vgpu->dmabuf_obj_list_head) {
139 			dmabuf_obj = list_entry(pos, struct intel_vgpu_dmabuf_obj, list);
140 			if (dmabuf_obj == obj) {
141 				list_del(pos);
142 				idr_remove(&vgpu->object_idr,
143 					   dmabuf_obj->dmabuf_id);
144 				kfree(dmabuf_obj->info);
145 				kfree(dmabuf_obj);
146 				break;
147 			}
148 		}
149 	} else {
150 		/* Free the orphan dmabuf_objs here */
151 		kfree(obj->info);
152 		kfree(obj);
153 	}
154 }
155 
156 
157 static inline void dmabuf_obj_get(struct intel_vgpu_dmabuf_obj *obj)
158 {
159 	kref_get(&obj->kref);
160 }
161 
162 static inline void dmabuf_obj_put(struct intel_vgpu_dmabuf_obj *obj)
163 {
164 	kref_put(&obj->kref, dmabuf_gem_object_free);
165 }
166 
167 static void vgpu_gem_release(struct drm_i915_gem_object *gem_obj)
168 {
169 
170 	struct intel_vgpu_fb_info *fb_info = gem_obj->gvt_info;
171 	struct intel_vgpu_dmabuf_obj *obj = fb_info->obj;
172 	struct intel_vgpu *vgpu = obj->vgpu;
173 
174 	if (vgpu) {
175 		mutex_lock(&vgpu->dmabuf_lock);
176 		gem_obj->base.dma_buf = NULL;
177 		dmabuf_obj_put(obj);
178 		mutex_unlock(&vgpu->dmabuf_lock);
179 	} else {
180 		/* vgpu is NULL, as it has been removed already */
181 		gem_obj->base.dma_buf = NULL;
182 		dmabuf_obj_put(obj);
183 	}
184 }
185 
186 static const struct drm_i915_gem_object_ops intel_vgpu_gem_ops = {
187 	.name = "i915_gem_object_vgpu",
188 	.flags = I915_GEM_OBJECT_IS_PROXY,
189 	.get_pages = vgpu_gem_get_pages,
190 	.put_pages = vgpu_gem_put_pages,
191 	.release = vgpu_gem_release,
192 };
193 
194 static struct drm_i915_gem_object *vgpu_create_gem(struct drm_device *dev,
195 		struct intel_vgpu_fb_info *info)
196 {
197 	static struct lock_class_key lock_class;
198 	struct drm_i915_private *dev_priv = to_i915(dev);
199 	struct drm_i915_gem_object *obj;
200 
201 	obj = i915_gem_object_alloc();
202 	if (obj == NULL)
203 		return NULL;
204 
205 	drm_gem_private_object_init(dev, &obj->base,
206 		roundup(info->size, PAGE_SIZE));
207 	i915_gem_object_init(obj, &intel_vgpu_gem_ops, &lock_class, 0);
208 	i915_gem_object_set_readonly(obj);
209 
210 	obj->read_domains = I915_GEM_DOMAIN_GTT;
211 	obj->write_domain = 0;
212 	if (GRAPHICS_VER(dev_priv) >= 9) {
213 		unsigned int tiling_mode = 0;
214 		unsigned int stride = 0;
215 
216 		switch (info->drm_format_mod) {
217 		case DRM_FORMAT_MOD_LINEAR:
218 			tiling_mode = I915_TILING_NONE;
219 			break;
220 		case I915_FORMAT_MOD_X_TILED:
221 			tiling_mode = I915_TILING_X;
222 			stride = info->stride;
223 			break;
224 		case I915_FORMAT_MOD_Y_TILED:
225 		case I915_FORMAT_MOD_Yf_TILED:
226 			tiling_mode = I915_TILING_Y;
227 			stride = info->stride;
228 			break;
229 		default:
230 			gvt_dbg_core("invalid drm_format_mod %llx for tiling\n",
231 				     info->drm_format_mod);
232 		}
233 		obj->tiling_and_stride = tiling_mode | stride;
234 	} else {
235 		obj->tiling_and_stride = info->drm_format_mod ?
236 					I915_TILING_X : 0;
237 	}
238 
239 	return obj;
240 }
241 
242 static bool validate_hotspot(struct intel_vgpu_cursor_plane_format *c)
243 {
244 	if (c && c->x_hot <= c->width && c->y_hot <= c->height)
245 		return true;
246 	else
247 		return false;
248 }
249 
250 static int vgpu_get_plane_info(struct drm_device *dev,
251 		struct intel_vgpu *vgpu,
252 		struct intel_vgpu_fb_info *info,
253 		int plane_id)
254 {
255 	struct intel_vgpu_primary_plane_format p;
256 	struct intel_vgpu_cursor_plane_format c;
257 	int ret, tile_height = 1;
258 
259 	memset(info, 0, sizeof(*info));
260 
261 	if (plane_id == DRM_PLANE_TYPE_PRIMARY) {
262 		ret = intel_vgpu_decode_primary_plane(vgpu, &p);
263 		if (ret)
264 			return ret;
265 		info->start = p.base;
266 		info->start_gpa = p.base_gpa;
267 		info->width = p.width;
268 		info->height = p.height;
269 		info->stride = p.stride;
270 		info->drm_format = p.drm_format;
271 
272 		switch (p.tiled) {
273 		case PLANE_CTL_TILED_LINEAR:
274 			info->drm_format_mod = DRM_FORMAT_MOD_LINEAR;
275 			break;
276 		case PLANE_CTL_TILED_X:
277 			info->drm_format_mod = I915_FORMAT_MOD_X_TILED;
278 			tile_height = 8;
279 			break;
280 		case PLANE_CTL_TILED_Y:
281 			info->drm_format_mod = I915_FORMAT_MOD_Y_TILED;
282 			tile_height = 32;
283 			break;
284 		case PLANE_CTL_TILED_YF:
285 			info->drm_format_mod = I915_FORMAT_MOD_Yf_TILED;
286 			tile_height = 32;
287 			break;
288 		default:
289 			gvt_vgpu_err("invalid tiling mode: %x\n", p.tiled);
290 		}
291 	} else if (plane_id == DRM_PLANE_TYPE_CURSOR) {
292 		ret = intel_vgpu_decode_cursor_plane(vgpu, &c);
293 		if (ret)
294 			return ret;
295 		info->start = c.base;
296 		info->start_gpa = c.base_gpa;
297 		info->width = c.width;
298 		info->height = c.height;
299 		info->stride = c.width * (c.bpp / 8);
300 		info->drm_format = c.drm_format;
301 		info->drm_format_mod = 0;
302 		info->x_pos = c.x_pos;
303 		info->y_pos = c.y_pos;
304 
305 		if (validate_hotspot(&c)) {
306 			info->x_hot = c.x_hot;
307 			info->y_hot = c.y_hot;
308 		} else {
309 			info->x_hot = UINT_MAX;
310 			info->y_hot = UINT_MAX;
311 		}
312 	} else {
313 		gvt_vgpu_err("invalid plane id:%d\n", plane_id);
314 		return -EINVAL;
315 	}
316 
317 	info->size = info->stride * roundup(info->height, tile_height);
318 	if (info->size == 0) {
319 		gvt_vgpu_err("fb size is zero\n");
320 		return -EINVAL;
321 	}
322 
323 	if (info->start & (PAGE_SIZE - 1)) {
324 		gvt_vgpu_err("Not aligned fb address:0x%llx\n", info->start);
325 		return -EFAULT;
326 	}
327 
328 	if (!intel_gvt_ggtt_validate_range(vgpu, info->start, info->size)) {
329 		gvt_vgpu_err("invalid gma addr\n");
330 		return -EFAULT;
331 	}
332 
333 	return 0;
334 }
335 
336 static struct intel_vgpu_dmabuf_obj *
337 pick_dmabuf_by_info(struct intel_vgpu *vgpu,
338 		    struct intel_vgpu_fb_info *latest_info)
339 {
340 	struct list_head *pos;
341 	struct intel_vgpu_fb_info *fb_info;
342 	struct intel_vgpu_dmabuf_obj *dmabuf_obj = NULL;
343 	struct intel_vgpu_dmabuf_obj *ret = NULL;
344 
345 	list_for_each(pos, &vgpu->dmabuf_obj_list_head) {
346 		dmabuf_obj = list_entry(pos, struct intel_vgpu_dmabuf_obj, list);
347 		if (!dmabuf_obj->info)
348 			continue;
349 
350 		fb_info = (struct intel_vgpu_fb_info *)dmabuf_obj->info;
351 		if ((fb_info->start == latest_info->start) &&
352 		    (fb_info->start_gpa == latest_info->start_gpa) &&
353 		    (fb_info->size == latest_info->size) &&
354 		    (fb_info->drm_format_mod == latest_info->drm_format_mod) &&
355 		    (fb_info->drm_format == latest_info->drm_format) &&
356 		    (fb_info->width == latest_info->width) &&
357 		    (fb_info->height == latest_info->height)) {
358 			ret = dmabuf_obj;
359 			break;
360 		}
361 	}
362 
363 	return ret;
364 }
365 
366 static struct intel_vgpu_dmabuf_obj *
367 pick_dmabuf_by_num(struct intel_vgpu *vgpu, u32 id)
368 {
369 	struct list_head *pos;
370 	struct intel_vgpu_dmabuf_obj *dmabuf_obj = NULL;
371 	struct intel_vgpu_dmabuf_obj *ret = NULL;
372 
373 	list_for_each(pos, &vgpu->dmabuf_obj_list_head) {
374 		dmabuf_obj = list_entry(pos, struct intel_vgpu_dmabuf_obj, list);
375 		if (dmabuf_obj->dmabuf_id == id) {
376 			ret = dmabuf_obj;
377 			break;
378 		}
379 	}
380 
381 	return ret;
382 }
383 
384 static void update_fb_info(struct vfio_device_gfx_plane_info *gvt_dmabuf,
385 		      struct intel_vgpu_fb_info *fb_info)
386 {
387 	gvt_dmabuf->drm_format = fb_info->drm_format;
388 	gvt_dmabuf->drm_format_mod = fb_info->drm_format_mod;
389 	gvt_dmabuf->width = fb_info->width;
390 	gvt_dmabuf->height = fb_info->height;
391 	gvt_dmabuf->stride = fb_info->stride;
392 	gvt_dmabuf->size = fb_info->size;
393 	gvt_dmabuf->x_pos = fb_info->x_pos;
394 	gvt_dmabuf->y_pos = fb_info->y_pos;
395 	gvt_dmabuf->x_hot = fb_info->x_hot;
396 	gvt_dmabuf->y_hot = fb_info->y_hot;
397 }
398 
399 int intel_vgpu_query_plane(struct intel_vgpu *vgpu, void *args)
400 {
401 	struct drm_device *dev = &vgpu->gvt->gt->i915->drm;
402 	struct vfio_device_gfx_plane_info *gfx_plane_info = args;
403 	struct intel_vgpu_dmabuf_obj *dmabuf_obj;
404 	struct intel_vgpu_fb_info fb_info;
405 	int ret = 0;
406 
407 	if (gfx_plane_info->flags == (VFIO_GFX_PLANE_TYPE_DMABUF |
408 				       VFIO_GFX_PLANE_TYPE_PROBE))
409 		return ret;
410 	else if ((gfx_plane_info->flags & ~VFIO_GFX_PLANE_TYPE_DMABUF) ||
411 			(!gfx_plane_info->flags))
412 		return -EINVAL;
413 
414 	ret = vgpu_get_plane_info(dev, vgpu, &fb_info,
415 					gfx_plane_info->drm_plane_type);
416 	if (ret != 0)
417 		goto out;
418 
419 	mutex_lock(&vgpu->dmabuf_lock);
420 	/* If exists, pick up the exposed dmabuf_obj */
421 	dmabuf_obj = pick_dmabuf_by_info(vgpu, &fb_info);
422 	if (dmabuf_obj) {
423 		update_fb_info(gfx_plane_info, &fb_info);
424 		gfx_plane_info->dmabuf_id = dmabuf_obj->dmabuf_id;
425 
426 		/* This buffer may be released between query_plane ioctl and
427 		 * get_dmabuf ioctl. Add the refcount to make sure it won't
428 		 * be released between the two ioctls.
429 		 */
430 		if (!dmabuf_obj->initref) {
431 			dmabuf_obj->initref = true;
432 			dmabuf_obj_get(dmabuf_obj);
433 		}
434 		ret = 0;
435 		gvt_dbg_dpy("vgpu%d: re-use dmabuf_obj ref %d, id %d\n",
436 			    vgpu->id, kref_read(&dmabuf_obj->kref),
437 			    gfx_plane_info->dmabuf_id);
438 		mutex_unlock(&vgpu->dmabuf_lock);
439 		goto out;
440 	}
441 
442 	mutex_unlock(&vgpu->dmabuf_lock);
443 
444 	/* Need to allocate a new one*/
445 	dmabuf_obj = kmalloc(sizeof(struct intel_vgpu_dmabuf_obj), GFP_KERNEL);
446 	if (unlikely(!dmabuf_obj)) {
447 		gvt_vgpu_err("alloc dmabuf_obj failed\n");
448 		ret = -ENOMEM;
449 		goto out;
450 	}
451 
452 	dmabuf_obj->info = kmalloc(sizeof(struct intel_vgpu_fb_info),
453 				   GFP_KERNEL);
454 	if (unlikely(!dmabuf_obj->info)) {
455 		gvt_vgpu_err("allocate intel vgpu fb info failed\n");
456 		ret = -ENOMEM;
457 		goto out_free_dmabuf;
458 	}
459 	memcpy(dmabuf_obj->info, &fb_info, sizeof(struct intel_vgpu_fb_info));
460 
461 	((struct intel_vgpu_fb_info *)dmabuf_obj->info)->obj = dmabuf_obj;
462 
463 	dmabuf_obj->vgpu = vgpu;
464 
465 	ret = idr_alloc(&vgpu->object_idr, dmabuf_obj, 1, 0, GFP_NOWAIT);
466 	if (ret < 0)
467 		goto out_free_info;
468 	gfx_plane_info->dmabuf_id = ret;
469 	dmabuf_obj->dmabuf_id = ret;
470 
471 	dmabuf_obj->initref = true;
472 
473 	kref_init(&dmabuf_obj->kref);
474 
475 	update_fb_info(gfx_plane_info, &fb_info);
476 
477 	INIT_LIST_HEAD(&dmabuf_obj->list);
478 	mutex_lock(&vgpu->dmabuf_lock);
479 	list_add_tail(&dmabuf_obj->list, &vgpu->dmabuf_obj_list_head);
480 	mutex_unlock(&vgpu->dmabuf_lock);
481 
482 	gvt_dbg_dpy("vgpu%d: %s new dmabuf_obj ref %d, id %d\n", vgpu->id,
483 		    __func__, kref_read(&dmabuf_obj->kref), ret);
484 
485 	return 0;
486 
487 out_free_info:
488 	kfree(dmabuf_obj->info);
489 out_free_dmabuf:
490 	kfree(dmabuf_obj);
491 out:
492 	/* ENODEV means plane isn't ready, which might be a normal case. */
493 	return (ret == -ENODEV) ? 0 : ret;
494 }
495 
496 /* To associate an exposed dmabuf with the dmabuf_obj */
497 int intel_vgpu_get_dmabuf(struct intel_vgpu *vgpu, unsigned int dmabuf_id)
498 {
499 	struct drm_device *dev = &vgpu->gvt->gt->i915->drm;
500 	struct intel_vgpu_dmabuf_obj *dmabuf_obj;
501 	struct drm_i915_gem_object *obj;
502 	struct dma_buf *dmabuf;
503 	int dmabuf_fd;
504 	int ret = 0;
505 
506 	mutex_lock(&vgpu->dmabuf_lock);
507 
508 	dmabuf_obj = pick_dmabuf_by_num(vgpu, dmabuf_id);
509 	if (dmabuf_obj == NULL) {
510 		gvt_vgpu_err("invalid dmabuf id:%d\n", dmabuf_id);
511 		ret = -EINVAL;
512 		goto out;
513 	}
514 
515 	obj = vgpu_create_gem(dev, dmabuf_obj->info);
516 	if (obj == NULL) {
517 		gvt_vgpu_err("create gvt gem obj failed\n");
518 		ret = -ENOMEM;
519 		goto out;
520 	}
521 
522 	obj->gvt_info = dmabuf_obj->info;
523 
524 	dmabuf = i915_gem_prime_export(&obj->base, DRM_CLOEXEC | DRM_RDWR);
525 	if (IS_ERR(dmabuf)) {
526 		gvt_vgpu_err("export dma-buf failed\n");
527 		ret = PTR_ERR(dmabuf);
528 		goto out_free_gem;
529 	}
530 
531 	ret = dma_buf_fd(dmabuf, DRM_CLOEXEC | DRM_RDWR);
532 	if (ret < 0) {
533 		gvt_vgpu_err("create dma-buf fd failed ret:%d\n", ret);
534 		goto out_free_dmabuf;
535 	}
536 	dmabuf_fd = ret;
537 
538 	dmabuf_obj_get(dmabuf_obj);
539 
540 	if (dmabuf_obj->initref) {
541 		dmabuf_obj->initref = false;
542 		dmabuf_obj_put(dmabuf_obj);
543 	}
544 
545 	mutex_unlock(&vgpu->dmabuf_lock);
546 
547 	gvt_dbg_dpy("vgpu%d: dmabuf:%d, dmabuf ref %d, fd:%d\n"
548 		    "        file count: %ld, GEM ref: %d\n",
549 		    vgpu->id, dmabuf_obj->dmabuf_id,
550 		    kref_read(&dmabuf_obj->kref),
551 		    dmabuf_fd,
552 		    file_count(dmabuf->file),
553 		    kref_read(&obj->base.refcount));
554 
555 	i915_gem_object_put(obj);
556 
557 	return dmabuf_fd;
558 
559 out_free_dmabuf:
560 	dma_buf_put(dmabuf);
561 out_free_gem:
562 	i915_gem_object_put(obj);
563 out:
564 	mutex_unlock(&vgpu->dmabuf_lock);
565 	return ret;
566 }
567 
568 void intel_vgpu_dmabuf_cleanup(struct intel_vgpu *vgpu)
569 {
570 	struct list_head *pos, *n;
571 	struct intel_vgpu_dmabuf_obj *dmabuf_obj;
572 
573 	mutex_lock(&vgpu->dmabuf_lock);
574 	list_for_each_safe(pos, n, &vgpu->dmabuf_obj_list_head) {
575 		dmabuf_obj = list_entry(pos, struct intel_vgpu_dmabuf_obj, list);
576 		dmabuf_obj->vgpu = NULL;
577 
578 		idr_remove(&vgpu->object_idr, dmabuf_obj->dmabuf_id);
579 		list_del(pos);
580 
581 		/* dmabuf_obj might be freed in dmabuf_obj_put */
582 		if (dmabuf_obj->initref) {
583 			dmabuf_obj->initref = false;
584 			dmabuf_obj_put(dmabuf_obj);
585 		}
586 
587 	}
588 	mutex_unlock(&vgpu->dmabuf_lock);
589 }
590