xref: /linux/drivers/gpu/drm/i915/gvt/dmabuf.c (revision 815e260a18a3af4dab59025ee99a7156c0e8b5e0)
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 #include <drm/drm_print.h>
37 
38 #include "gem/i915_gem_dmabuf.h"
39 
40 #include "i915_drv.h"
41 #include "gvt.h"
42 
43 #include "display/skl_universal_plane_regs.h"
44 
45 #define GEN8_DECODE_PTE(pte) (pte & GENMASK_ULL(63, 12))
46 
47 static int vgpu_gem_get_pages(struct drm_i915_gem_object *obj)
48 {
49 	struct drm_i915_private *dev_priv = to_i915(obj->base.dev);
50 	struct intel_vgpu *vgpu;
51 	struct sg_table *st;
52 	struct scatterlist *sg;
53 	int i, j, ret;
54 	gen8_pte_t __iomem *gtt_entries;
55 	struct intel_vgpu_fb_info *fb_info;
56 	unsigned int page_num; /* limited by sg_alloc_table */
57 
58 	if (overflows_type(obj->base.size >> PAGE_SHIFT, page_num))
59 		return -E2BIG;
60 
61 	page_num = obj->base.size >> PAGE_SHIFT;
62 	fb_info = (struct intel_vgpu_fb_info *)obj->gvt_info;
63 	if (drm_WARN_ON(&dev_priv->drm, !fb_info))
64 		return -ENODEV;
65 
66 	vgpu = fb_info->obj->vgpu;
67 	if (drm_WARN_ON(&dev_priv->drm, !vgpu))
68 		return -ENODEV;
69 
70 	st = kmalloc(sizeof(*st), GFP_KERNEL);
71 	if (unlikely(!st))
72 		return -ENOMEM;
73 
74 	ret = sg_alloc_table(st, page_num, GFP_KERNEL);
75 	if (ret) {
76 		kfree(st);
77 		return ret;
78 	}
79 	gtt_entries = (gen8_pte_t __iomem *)to_gt(dev_priv)->ggtt->gsm +
80 		(fb_info->start >> PAGE_SHIFT);
81 	for_each_sg(st->sgl, sg, page_num, i) {
82 		dma_addr_t dma_addr =
83 			GEN8_DECODE_PTE(readq(&gtt_entries[i]));
84 		if (intel_gvt_dma_pin_guest_page(vgpu, dma_addr)) {
85 			ret = -EINVAL;
86 			goto out;
87 		}
88 
89 		sg->offset = 0;
90 		sg->length = PAGE_SIZE;
91 		sg_dma_len(sg) = PAGE_SIZE;
92 		sg_dma_address(sg) = dma_addr;
93 	}
94 
95 	__i915_gem_object_set_pages(obj, st);
96 out:
97 	if (ret) {
98 		dma_addr_t dma_addr;
99 
100 		for_each_sg(st->sgl, sg, i, j) {
101 			dma_addr = sg_dma_address(sg);
102 			if (dma_addr)
103 				intel_gvt_dma_unmap_guest_page(vgpu, dma_addr);
104 		}
105 		sg_free_table(st);
106 		kfree(st);
107 	}
108 
109 	return ret;
110 
111 }
112 
113 static void vgpu_gem_put_pages(struct drm_i915_gem_object *obj,
114 		struct sg_table *pages)
115 {
116 	struct scatterlist *sg;
117 
118 	if (obj->base.dma_buf) {
119 		struct intel_vgpu_fb_info *fb_info = obj->gvt_info;
120 		struct intel_vgpu_dmabuf_obj *obj = fb_info->obj;
121 		struct intel_vgpu *vgpu = obj->vgpu;
122 		int i;
123 
124 		for_each_sg(pages->sgl, sg, fb_info->size, i)
125 			intel_gvt_dma_unmap_guest_page(vgpu,
126 					       sg_dma_address(sg));
127 	}
128 
129 	sg_free_table(pages);
130 	kfree(pages);
131 }
132 
133 static void dmabuf_gem_object_free(struct kref *kref)
134 {
135 	struct intel_vgpu_dmabuf_obj *obj =
136 		container_of(kref, struct intel_vgpu_dmabuf_obj, kref);
137 	struct intel_vgpu *vgpu = obj->vgpu;
138 	struct list_head *pos;
139 	struct intel_vgpu_dmabuf_obj *dmabuf_obj;
140 
141 	if (vgpu && test_bit(INTEL_VGPU_STATUS_ACTIVE, vgpu->status) &&
142 	    !list_empty(&vgpu->dmabuf_obj_list_head)) {
143 		list_for_each(pos, &vgpu->dmabuf_obj_list_head) {
144 			dmabuf_obj = list_entry(pos, struct intel_vgpu_dmabuf_obj, list);
145 			if (dmabuf_obj == obj) {
146 				list_del(pos);
147 				idr_remove(&vgpu->object_idr,
148 					   dmabuf_obj->dmabuf_id);
149 				kfree(dmabuf_obj->info);
150 				kfree(dmabuf_obj);
151 				break;
152 			}
153 		}
154 	} else {
155 		/* Free the orphan dmabuf_objs here */
156 		kfree(obj->info);
157 		kfree(obj);
158 	}
159 }
160 
161 
162 static inline void dmabuf_obj_get(struct intel_vgpu_dmabuf_obj *obj)
163 {
164 	kref_get(&obj->kref);
165 }
166 
167 static inline void dmabuf_obj_put(struct intel_vgpu_dmabuf_obj *obj)
168 {
169 	kref_put(&obj->kref, dmabuf_gem_object_free);
170 }
171 
172 static void vgpu_gem_release(struct drm_i915_gem_object *gem_obj)
173 {
174 
175 	struct intel_vgpu_fb_info *fb_info = gem_obj->gvt_info;
176 	struct intel_vgpu_dmabuf_obj *obj = fb_info->obj;
177 	struct intel_vgpu *vgpu = obj->vgpu;
178 
179 	if (vgpu) {
180 		mutex_lock(&vgpu->dmabuf_lock);
181 		gem_obj->base.dma_buf = NULL;
182 		dmabuf_obj_put(obj);
183 		mutex_unlock(&vgpu->dmabuf_lock);
184 	} else {
185 		/* vgpu is NULL, as it has been removed already */
186 		gem_obj->base.dma_buf = NULL;
187 		dmabuf_obj_put(obj);
188 	}
189 }
190 
191 static const struct drm_i915_gem_object_ops intel_vgpu_gem_ops = {
192 	.name = "i915_gem_object_vgpu",
193 	.flags = I915_GEM_OBJECT_IS_PROXY,
194 	.get_pages = vgpu_gem_get_pages,
195 	.put_pages = vgpu_gem_put_pages,
196 	.release = vgpu_gem_release,
197 };
198 
199 static struct drm_i915_gem_object *vgpu_create_gem(struct drm_device *dev,
200 		struct intel_vgpu_fb_info *info)
201 {
202 	static struct lock_class_key lock_class;
203 	struct drm_i915_private *dev_priv = to_i915(dev);
204 	struct drm_i915_gem_object *obj;
205 
206 	obj = i915_gem_object_alloc();
207 	if (obj == NULL)
208 		return NULL;
209 
210 	drm_gem_private_object_init(dev, &obj->base,
211 		roundup(info->size, PAGE_SIZE));
212 	i915_gem_object_init(obj, &intel_vgpu_gem_ops, &lock_class, 0);
213 	i915_gem_object_set_readonly(obj);
214 
215 	obj->read_domains = I915_GEM_DOMAIN_GTT;
216 	obj->write_domain = 0;
217 	if (GRAPHICS_VER(dev_priv) >= 9) {
218 		unsigned int tiling_mode = 0;
219 		unsigned int stride = 0;
220 
221 		switch (info->drm_format_mod) {
222 		case DRM_FORMAT_MOD_LINEAR:
223 			tiling_mode = I915_TILING_NONE;
224 			break;
225 		case I915_FORMAT_MOD_X_TILED:
226 			tiling_mode = I915_TILING_X;
227 			stride = info->stride;
228 			break;
229 		case I915_FORMAT_MOD_Y_TILED:
230 		case I915_FORMAT_MOD_Yf_TILED:
231 			tiling_mode = I915_TILING_Y;
232 			stride = info->stride;
233 			break;
234 		default:
235 			gvt_dbg_core("invalid drm_format_mod %llx for tiling\n",
236 				     info->drm_format_mod);
237 		}
238 		obj->tiling_and_stride = tiling_mode | stride;
239 	} else {
240 		obj->tiling_and_stride = info->drm_format_mod ?
241 					I915_TILING_X : 0;
242 	}
243 
244 	return obj;
245 }
246 
247 static bool validate_hotspot(struct intel_vgpu_cursor_plane_format *c)
248 {
249 	if (c && c->x_hot <= c->width && c->y_hot <= c->height)
250 		return true;
251 	else
252 		return false;
253 }
254 
255 static int vgpu_get_plane_info(struct drm_device *dev,
256 		struct intel_vgpu *vgpu,
257 		struct intel_vgpu_fb_info *info,
258 		int plane_id)
259 {
260 	struct intel_vgpu_primary_plane_format p;
261 	struct intel_vgpu_cursor_plane_format c;
262 	int ret, tile_height = 1;
263 
264 	memset(info, 0, sizeof(*info));
265 
266 	if (plane_id == DRM_PLANE_TYPE_PRIMARY) {
267 		ret = intel_vgpu_decode_primary_plane(vgpu, &p);
268 		if (ret)
269 			return ret;
270 		info->start = p.base;
271 		info->start_gpa = p.base_gpa;
272 		info->width = p.width;
273 		info->height = p.height;
274 		info->stride = p.stride;
275 		info->drm_format = p.drm_format;
276 
277 		switch (p.tiled) {
278 		case PLANE_CTL_TILED_LINEAR:
279 			info->drm_format_mod = DRM_FORMAT_MOD_LINEAR;
280 			break;
281 		case PLANE_CTL_TILED_X:
282 			info->drm_format_mod = I915_FORMAT_MOD_X_TILED;
283 			tile_height = 8;
284 			break;
285 		case PLANE_CTL_TILED_Y:
286 			info->drm_format_mod = I915_FORMAT_MOD_Y_TILED;
287 			tile_height = 32;
288 			break;
289 		case PLANE_CTL_TILED_YF:
290 			info->drm_format_mod = I915_FORMAT_MOD_Yf_TILED;
291 			tile_height = 32;
292 			break;
293 		default:
294 			gvt_vgpu_err("invalid tiling mode: %x\n", p.tiled);
295 		}
296 	} else if (plane_id == DRM_PLANE_TYPE_CURSOR) {
297 		ret = intel_vgpu_decode_cursor_plane(vgpu, &c);
298 		if (ret)
299 			return ret;
300 		info->start = c.base;
301 		info->start_gpa = c.base_gpa;
302 		info->width = c.width;
303 		info->height = c.height;
304 		info->stride = c.width * (c.bpp / 8);
305 		info->drm_format = c.drm_format;
306 		info->drm_format_mod = 0;
307 		info->x_pos = c.x_pos;
308 		info->y_pos = c.y_pos;
309 
310 		if (validate_hotspot(&c)) {
311 			info->x_hot = c.x_hot;
312 			info->y_hot = c.y_hot;
313 		} else {
314 			info->x_hot = UINT_MAX;
315 			info->y_hot = UINT_MAX;
316 		}
317 	} else {
318 		gvt_vgpu_err("invalid plane id:%d\n", plane_id);
319 		return -EINVAL;
320 	}
321 
322 	info->size = info->stride * roundup(info->height, tile_height);
323 	if (info->size == 0) {
324 		gvt_vgpu_err("fb size is zero\n");
325 		return -EINVAL;
326 	}
327 
328 	if (info->start & (PAGE_SIZE - 1)) {
329 		gvt_vgpu_err("Not aligned fb address:0x%llx\n", info->start);
330 		return -EFAULT;
331 	}
332 
333 	if (!intel_gvt_ggtt_validate_range(vgpu, info->start, info->size)) {
334 		gvt_vgpu_err("invalid gma addr\n");
335 		return -EFAULT;
336 	}
337 
338 	return 0;
339 }
340 
341 static struct intel_vgpu_dmabuf_obj *
342 pick_dmabuf_by_info(struct intel_vgpu *vgpu,
343 		    struct intel_vgpu_fb_info *latest_info)
344 {
345 	struct list_head *pos;
346 	struct intel_vgpu_fb_info *fb_info;
347 	struct intel_vgpu_dmabuf_obj *dmabuf_obj = NULL;
348 	struct intel_vgpu_dmabuf_obj *ret = NULL;
349 
350 	list_for_each(pos, &vgpu->dmabuf_obj_list_head) {
351 		dmabuf_obj = list_entry(pos, struct intel_vgpu_dmabuf_obj, list);
352 		if (!dmabuf_obj->info)
353 			continue;
354 
355 		fb_info = (struct intel_vgpu_fb_info *)dmabuf_obj->info;
356 		if ((fb_info->start == latest_info->start) &&
357 		    (fb_info->start_gpa == latest_info->start_gpa) &&
358 		    (fb_info->size == latest_info->size) &&
359 		    (fb_info->drm_format_mod == latest_info->drm_format_mod) &&
360 		    (fb_info->drm_format == latest_info->drm_format) &&
361 		    (fb_info->width == latest_info->width) &&
362 		    (fb_info->height == latest_info->height)) {
363 			ret = dmabuf_obj;
364 			break;
365 		}
366 	}
367 
368 	return ret;
369 }
370 
371 static struct intel_vgpu_dmabuf_obj *
372 pick_dmabuf_by_num(struct intel_vgpu *vgpu, u32 id)
373 {
374 	struct list_head *pos;
375 	struct intel_vgpu_dmabuf_obj *dmabuf_obj = NULL;
376 	struct intel_vgpu_dmabuf_obj *ret = NULL;
377 
378 	list_for_each(pos, &vgpu->dmabuf_obj_list_head) {
379 		dmabuf_obj = list_entry(pos, struct intel_vgpu_dmabuf_obj, list);
380 		if (dmabuf_obj->dmabuf_id == id) {
381 			ret = dmabuf_obj;
382 			break;
383 		}
384 	}
385 
386 	return ret;
387 }
388 
389 static void update_fb_info(struct vfio_device_gfx_plane_info *gvt_dmabuf,
390 		      struct intel_vgpu_fb_info *fb_info)
391 {
392 	gvt_dmabuf->drm_format = fb_info->drm_format;
393 	gvt_dmabuf->drm_format_mod = fb_info->drm_format_mod;
394 	gvt_dmabuf->width = fb_info->width;
395 	gvt_dmabuf->height = fb_info->height;
396 	gvt_dmabuf->stride = fb_info->stride;
397 	gvt_dmabuf->size = fb_info->size;
398 	gvt_dmabuf->x_pos = fb_info->x_pos;
399 	gvt_dmabuf->y_pos = fb_info->y_pos;
400 	gvt_dmabuf->x_hot = fb_info->x_hot;
401 	gvt_dmabuf->y_hot = fb_info->y_hot;
402 }
403 
404 int intel_vgpu_query_plane(struct intel_vgpu *vgpu, void *args)
405 {
406 	struct drm_device *dev = &vgpu->gvt->gt->i915->drm;
407 	struct vfio_device_gfx_plane_info *gfx_plane_info = args;
408 	struct intel_vgpu_dmabuf_obj *dmabuf_obj;
409 	struct intel_vgpu_fb_info fb_info;
410 	int ret = 0;
411 
412 	if (gfx_plane_info->flags == (VFIO_GFX_PLANE_TYPE_DMABUF |
413 				       VFIO_GFX_PLANE_TYPE_PROBE))
414 		return ret;
415 	else if ((gfx_plane_info->flags & ~VFIO_GFX_PLANE_TYPE_DMABUF) ||
416 			(!gfx_plane_info->flags))
417 		return -EINVAL;
418 
419 	ret = vgpu_get_plane_info(dev, vgpu, &fb_info,
420 					gfx_plane_info->drm_plane_type);
421 	if (ret != 0)
422 		goto out;
423 
424 	mutex_lock(&vgpu->dmabuf_lock);
425 	/* If exists, pick up the exposed dmabuf_obj */
426 	dmabuf_obj = pick_dmabuf_by_info(vgpu, &fb_info);
427 	if (dmabuf_obj) {
428 		update_fb_info(gfx_plane_info, &fb_info);
429 		gfx_plane_info->dmabuf_id = dmabuf_obj->dmabuf_id;
430 
431 		/* This buffer may be released between query_plane ioctl and
432 		 * get_dmabuf ioctl. Add the refcount to make sure it won't
433 		 * be released between the two ioctls.
434 		 */
435 		if (!dmabuf_obj->initref) {
436 			dmabuf_obj->initref = true;
437 			dmabuf_obj_get(dmabuf_obj);
438 		}
439 		ret = 0;
440 		gvt_dbg_dpy("vgpu%d: reuse dmabuf_obj ref %d, id %d\n",
441 			    vgpu->id, kref_read(&dmabuf_obj->kref),
442 			    gfx_plane_info->dmabuf_id);
443 		mutex_unlock(&vgpu->dmabuf_lock);
444 		goto out;
445 	}
446 
447 	mutex_unlock(&vgpu->dmabuf_lock);
448 
449 	/* Need to allocate a new one*/
450 	dmabuf_obj = kmalloc(sizeof(struct intel_vgpu_dmabuf_obj), GFP_KERNEL);
451 	if (unlikely(!dmabuf_obj)) {
452 		gvt_vgpu_err("alloc dmabuf_obj failed\n");
453 		ret = -ENOMEM;
454 		goto out;
455 	}
456 
457 	dmabuf_obj->info = kmalloc(sizeof(struct intel_vgpu_fb_info),
458 				   GFP_KERNEL);
459 	if (unlikely(!dmabuf_obj->info)) {
460 		gvt_vgpu_err("allocate intel vgpu fb info failed\n");
461 		ret = -ENOMEM;
462 		goto out_free_dmabuf;
463 	}
464 	memcpy(dmabuf_obj->info, &fb_info, sizeof(struct intel_vgpu_fb_info));
465 
466 	((struct intel_vgpu_fb_info *)dmabuf_obj->info)->obj = dmabuf_obj;
467 
468 	dmabuf_obj->vgpu = vgpu;
469 
470 	ret = idr_alloc(&vgpu->object_idr, dmabuf_obj, 1, 0, GFP_NOWAIT);
471 	if (ret < 0)
472 		goto out_free_info;
473 	gfx_plane_info->dmabuf_id = ret;
474 	dmabuf_obj->dmabuf_id = ret;
475 
476 	dmabuf_obj->initref = true;
477 
478 	kref_init(&dmabuf_obj->kref);
479 
480 	update_fb_info(gfx_plane_info, &fb_info);
481 
482 	INIT_LIST_HEAD(&dmabuf_obj->list);
483 	mutex_lock(&vgpu->dmabuf_lock);
484 	list_add_tail(&dmabuf_obj->list, &vgpu->dmabuf_obj_list_head);
485 	mutex_unlock(&vgpu->dmabuf_lock);
486 
487 	gvt_dbg_dpy("vgpu%d: %s new dmabuf_obj ref %d, id %d\n", vgpu->id,
488 		    __func__, kref_read(&dmabuf_obj->kref), ret);
489 
490 	return 0;
491 
492 out_free_info:
493 	kfree(dmabuf_obj->info);
494 out_free_dmabuf:
495 	kfree(dmabuf_obj);
496 out:
497 	/* ENODEV means plane isn't ready, which might be a normal case. */
498 	return (ret == -ENODEV) ? 0 : ret;
499 }
500 
501 /* To associate an exposed dmabuf with the dmabuf_obj */
502 int intel_vgpu_get_dmabuf(struct intel_vgpu *vgpu, unsigned int dmabuf_id)
503 {
504 	struct drm_device *dev = &vgpu->gvt->gt->i915->drm;
505 	struct intel_vgpu_dmabuf_obj *dmabuf_obj;
506 	struct drm_i915_gem_object *obj;
507 	struct dma_buf *dmabuf;
508 	int dmabuf_fd;
509 	int ret = 0;
510 
511 	mutex_lock(&vgpu->dmabuf_lock);
512 
513 	dmabuf_obj = pick_dmabuf_by_num(vgpu, dmabuf_id);
514 	if (dmabuf_obj == NULL) {
515 		gvt_vgpu_err("invalid dmabuf id:%d\n", dmabuf_id);
516 		ret = -EINVAL;
517 		goto out;
518 	}
519 
520 	obj = vgpu_create_gem(dev, dmabuf_obj->info);
521 	if (obj == NULL) {
522 		gvt_vgpu_err("create gvt gem obj failed\n");
523 		ret = -ENOMEM;
524 		goto out;
525 	}
526 
527 	obj->gvt_info = dmabuf_obj->info;
528 
529 	dmabuf = i915_gem_prime_export(&obj->base, DRM_CLOEXEC | DRM_RDWR);
530 	if (IS_ERR(dmabuf)) {
531 		gvt_vgpu_err("export dma-buf failed\n");
532 		ret = PTR_ERR(dmabuf);
533 		goto out_free_gem;
534 	}
535 
536 	ret = dma_buf_fd(dmabuf, DRM_CLOEXEC | DRM_RDWR);
537 	if (ret < 0) {
538 		gvt_vgpu_err("create dma-buf fd failed ret:%d\n", ret);
539 		goto out_free_dmabuf;
540 	}
541 	dmabuf_fd = ret;
542 
543 	dmabuf_obj_get(dmabuf_obj);
544 
545 	if (dmabuf_obj->initref) {
546 		dmabuf_obj->initref = false;
547 		dmabuf_obj_put(dmabuf_obj);
548 	}
549 
550 	mutex_unlock(&vgpu->dmabuf_lock);
551 
552 	gvt_dbg_dpy("vgpu%d: dmabuf:%d, dmabuf ref %d, fd:%d\n"
553 		    "        file count: %ld, GEM ref: %d\n",
554 		    vgpu->id, dmabuf_obj->dmabuf_id,
555 		    kref_read(&dmabuf_obj->kref),
556 		    dmabuf_fd,
557 		    file_count(dmabuf->file),
558 		    kref_read(&obj->base.refcount));
559 
560 	i915_gem_object_put(obj);
561 
562 	return dmabuf_fd;
563 
564 out_free_dmabuf:
565 	dma_buf_put(dmabuf);
566 out_free_gem:
567 	i915_gem_object_put(obj);
568 out:
569 	mutex_unlock(&vgpu->dmabuf_lock);
570 	return ret;
571 }
572 
573 void intel_vgpu_dmabuf_cleanup(struct intel_vgpu *vgpu)
574 {
575 	struct list_head *pos, *n;
576 	struct intel_vgpu_dmabuf_obj *dmabuf_obj;
577 
578 	mutex_lock(&vgpu->dmabuf_lock);
579 	list_for_each_safe(pos, n, &vgpu->dmabuf_obj_list_head) {
580 		dmabuf_obj = list_entry(pos, struct intel_vgpu_dmabuf_obj, list);
581 		dmabuf_obj->vgpu = NULL;
582 
583 		idr_remove(&vgpu->object_idr, dmabuf_obj->dmabuf_id);
584 		list_del(pos);
585 
586 		/* dmabuf_obj might be freed in dmabuf_obj_put */
587 		if (dmabuf_obj->initref) {
588 			dmabuf_obj->initref = false;
589 			dmabuf_obj_put(dmabuf_obj);
590 		}
591 
592 	}
593 	mutex_unlock(&vgpu->dmabuf_lock);
594 }
595