1 files changed, 154 insertions, 215 deletions

diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c
index 5914e79d3429..73854915ec34 100644
--- a/drivers/gpu/drm/virtio/virtgpu_vq.c
+++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
@@ -95,7 +95,8 @@ virtio_gpu_get_vbuf(struct virtio_gpu_device *vgdev,
 	if (!vbuf)
 		return ERR_PTR(-ENOMEM);
 
-	BUG_ON(size > MAX_INLINE_CMD_SIZE);
+	BUG_ON(size > MAX_INLINE_CMD_SIZE ||
+	       size < sizeof(struct virtio_gpu_ctrl_hdr));
 	vbuf->buf = (void *)vbuf + sizeof(*vbuf);
 	vbuf->size = size;
 
@@ -109,21 +110,14 @@ virtio_gpu_get_vbuf(struct virtio_gpu_device *vgdev,
 	return vbuf;
 }
 
-static void *virtio_gpu_alloc_cmd(struct virtio_gpu_device *vgdev,
-				  struct virtio_gpu_vbuffer **vbuffer_p,
-				  int size)
+static struct virtio_gpu_ctrl_hdr *
+virtio_gpu_vbuf_ctrl_hdr(struct virtio_gpu_vbuffer *vbuf)
 {
-	struct virtio_gpu_vbuffer *vbuf;
-
-	vbuf = virtio_gpu_get_vbuf(vgdev, size,
-				   sizeof(struct virtio_gpu_ctrl_hdr),
-				   NULL, NULL);
-	if (IS_ERR(vbuf)) {
-		*vbuffer_p = NULL;
-		return ERR_CAST(vbuf);
-	}
-	*vbuffer_p = vbuf;
-	return vbuf->buf;
+	/* this assumes a vbuf contains a command that starts with a
+	 * virtio_gpu_ctrl_hdr, which is true for both ctrl and cursor
+	 * virtqueues.
+	 */
+	return (struct virtio_gpu_ctrl_hdr *)vbuf->buf;
 }
 
 static struct virtio_gpu_update_cursor*
@@ -161,6 +155,25 @@ static void *virtio_gpu_alloc_cmd_resp(struct virtio_gpu_device *vgdev,
 	return (struct virtio_gpu_command *)vbuf->buf;
 }
 
+static void *virtio_gpu_alloc_cmd(struct virtio_gpu_device *vgdev,
+				  struct virtio_gpu_vbuffer **vbuffer_p,
+				  int size)
+{
+	return virtio_gpu_alloc_cmd_resp(vgdev, NULL, vbuffer_p, size,
+					 sizeof(struct virtio_gpu_ctrl_hdr),
+					 NULL);
+}
+
+static void *virtio_gpu_alloc_cmd_cb(struct virtio_gpu_device *vgdev,
+				     struct virtio_gpu_vbuffer **vbuffer_p,
+				     int size,
+				     virtio_gpu_resp_cb cb)
+{
+	return virtio_gpu_alloc_cmd_resp(vgdev, cb, vbuffer_p, size,
+					 sizeof(struct virtio_gpu_ctrl_hdr),
+					 NULL);
+}
+
 static void free_vbuf(struct virtio_gpu_device *vgdev,
 		      struct virtio_gpu_vbuffer *vbuf)
 {
@@ -209,12 +222,12 @@ void virtio_gpu_dequeue_ctrl_func(struct work_struct *work)
 		trace_virtio_gpu_cmd_response(vgdev->ctrlq.vq, resp);
 
 		if (resp->type != cpu_to_le32(VIRTIO_GPU_RESP_OK_NODATA)) {
-			if (resp->type >= cpu_to_le32(VIRTIO_GPU_RESP_ERR_UNSPEC)) {
+			if (le32_to_cpu(resp->type) >= VIRTIO_GPU_RESP_ERR_UNSPEC) {
 				struct virtio_gpu_ctrl_hdr *cmd;
-				cmd = (struct virtio_gpu_ctrl_hdr *)entry->buf;
-				DRM_ERROR("response 0x%x (command 0x%x)\n",
-					  le32_to_cpu(resp->type),
-					  le32_to_cpu(cmd->type));
+				cmd = virtio_gpu_vbuf_ctrl_hdr(entry);
+				DRM_ERROR_RATELIMITED("response 0x%x (command 0x%x)\n",
+						      le32_to_cpu(resp->type),
+						      le32_to_cpu(cmd->type));
 			} else
 				DRM_DEBUG("response 0x%x\n", le32_to_cpu(resp->type));
 		}
@@ -307,109 +320,107 @@ static struct sg_table *vmalloc_to_sgt(char *data, uint32_t size, int *sg_ents)
 	return sgt;
 }
 
-static bool virtio_gpu_queue_ctrl_buffer_locked(struct virtio_gpu_device *vgdev,
-						struct virtio_gpu_vbuffer *vbuf,
-						struct scatterlist *vout)
-		__releases(&vgdev->ctrlq.qlock)
-		__acquires(&vgdev->ctrlq.qlock)
+static void virtio_gpu_queue_ctrl_sgs(struct virtio_gpu_device *vgdev,
+				      struct virtio_gpu_vbuffer *vbuf,
+				      struct virtio_gpu_fence *fence,
+				      int elemcnt,
+				      struct scatterlist **sgs,
+				      int outcnt,
+				      int incnt)
 {
 	struct virtqueue *vq = vgdev->ctrlq.vq;
-	struct scatterlist *sgs[3], vcmd, vresp;
-	int outcnt = 0, incnt = 0;
-	bool notify = false;
-	int ret;
+	int ret, idx;
 
-	if (!vgdev->vqs_ready)
-		return notify;
+	if (!drm_dev_enter(vgdev->ddev, &idx)) {
+		if (fence && vbuf->objs)
+			virtio_gpu_array_unlock_resv(vbuf->objs);
+		free_vbuf(vgdev, vbuf);
+		return;
+	}
 
-	sg_init_one(&vcmd, vbuf->buf, vbuf->size);
-	sgs[outcnt + incnt] = &vcmd;
-	outcnt++;
+	if (vgdev->has_indirect)
+		elemcnt = 1;
 
-	if (vout) {
-		sgs[outcnt + incnt] = vout;
-		outcnt++;
+again:
+	spin_lock(&vgdev->ctrlq.qlock);
+
+	if (vq->num_free < elemcnt) {
+		spin_unlock(&vgdev->ctrlq.qlock);
+		virtio_gpu_notify(vgdev);
+		wait_event(vgdev->ctrlq.ack_queue, vq->num_free >= elemcnt);
+		goto again;
 	}
 
-	if (vbuf->resp_size) {
-		sg_init_one(&vresp, vbuf->resp_buf, vbuf->resp_size);
-		sgs[outcnt + incnt] = &vresp;
-		incnt++;
+	/* now that the position of the vbuf in the virtqueue is known, we can
+	 * finally set the fence id
+	 */
+	if (fence) {
+		virtio_gpu_fence_emit(vgdev, virtio_gpu_vbuf_ctrl_hdr(vbuf),
+				      fence);
+		if (vbuf->objs) {
+			virtio_gpu_array_add_fence(vbuf->objs, &fence->f);
+			virtio_gpu_array_unlock_resv(vbuf->objs);
+		}
 	}
 
-retry:
 	ret = virtqueue_add_sgs(vq, sgs, outcnt, incnt, vbuf, GFP_ATOMIC);
-	if (ret == -ENOSPC) {
-		spin_unlock(&vgdev->ctrlq.qlock);
-		wait_event(vgdev->ctrlq.ack_queue, vq->num_free >= outcnt + incnt);
-		spin_lock(&vgdev->ctrlq.qlock);
-		goto retry;
-	} else {
-		trace_virtio_gpu_cmd_queue(vq,
-			(struct virtio_gpu_ctrl_hdr *)vbuf->buf);
+	WARN_ON(ret);
 
-		notify = virtqueue_kick_prepare(vq);
-	}
-	return notify;
+	trace_virtio_gpu_cmd_queue(vq, virtio_gpu_vbuf_ctrl_hdr(vbuf));
+
+	atomic_inc(&vgdev->pending_commands);
+
+	spin_unlock(&vgdev->ctrlq.qlock);
+
+	drm_dev_exit(idx);
 }
 
 static void virtio_gpu_queue_fenced_ctrl_buffer(struct virtio_gpu_device *vgdev,
 						struct virtio_gpu_vbuffer *vbuf,
-						struct virtio_gpu_ctrl_hdr *hdr,
 						struct virtio_gpu_fence *fence)
 {
-	struct virtqueue *vq = vgdev->ctrlq.vq;
-	struct scatterlist *vout = NULL, sg;
+	struct scatterlist *sgs[3], vcmd, vout, vresp;
 	struct sg_table *sgt = NULL;
-	bool notify;
-	int outcnt = 0;
+	int elemcnt = 0, outcnt = 0, incnt = 0;
 
+	/* set up vcmd */
+	sg_init_one(&vcmd, vbuf->buf, vbuf->size);
+	elemcnt++;
+	sgs[outcnt] = &vcmd;
+	outcnt++;
+
+	/* set up vout */
 	if (vbuf->data_size) {
 		if (is_vmalloc_addr(vbuf->data_buf)) {
+			int sg_ents;
 			sgt = vmalloc_to_sgt(vbuf->data_buf, vbuf->data_size,
-					     &outcnt);
-			if (!sgt)
+					     &sg_ents);
+			if (!sgt) {
+				if (fence && vbuf->objs)
+					virtio_gpu_array_unlock_resv(vbuf->objs);
 				return;
-			vout = sgt->sgl;
+			}
+
+			elemcnt += sg_ents;
+			sgs[outcnt] = sgt->sgl;
 		} else {
-			sg_init_one(&sg, vbuf->data_buf, vbuf->data_size);
-			vout = &sg;
-			outcnt = 1;
+			sg_init_one(&vout, vbuf->data_buf, vbuf->data_size);
+			elemcnt++;
+			sgs[outcnt] = &vout;
 		}
+		outcnt++;
 	}
 
-again:
-	spin_lock(&vgdev->ctrlq.qlock);
-
-	/*
-	 * Make sure we have enouth space in the virtqueue.  If not
-	 * wait here until we have.
-	 *
-	 * Without that virtio_gpu_queue_ctrl_buffer_nolock might have
-	 * to wait for free space, which can result in fence ids being
-	 * submitted out-of-order.
-	 */
-	if (vq->num_free < 2 + outcnt) {
-		spin_unlock(&vgdev->ctrlq.qlock);
-		wait_event(vgdev->ctrlq.ack_queue, vq->num_free >= 3);
-		goto again;
+	/* set up vresp */
+	if (vbuf->resp_size) {
+		sg_init_one(&vresp, vbuf->resp_buf, vbuf->resp_size);
+		elemcnt++;
+		sgs[outcnt + incnt] = &vresp;
+		incnt++;
 	}
 
-	if (hdr && fence) {
-		virtio_gpu_fence_emit(vgdev, hdr, fence);
-		if (vbuf->objs) {
-			virtio_gpu_array_add_fence(vbuf->objs, &fence->f);
-			virtio_gpu_array_unlock_resv(vbuf->objs);
-		}
-	}
-	notify = virtio_gpu_queue_ctrl_buffer_locked(vgdev, vbuf, vout);
-	spin_unlock(&vgdev->ctrlq.qlock);
-	if (notify) {
-		if (vgdev->disable_notify)
-			vgdev->pending_notify = true;
-		else
-			virtqueue_notify(vgdev->ctrlq.vq);
-	}
+	virtio_gpu_queue_ctrl_sgs(vgdev, vbuf, fence, elemcnt, sgs, outcnt,
+				  incnt);
 
 	if (sgt) {
 		sg_free_table(sgt);
@@ -417,25 +428,26 @@ again:
 	}
 }
 
-void virtio_gpu_disable_notify(struct virtio_gpu_device *vgdev)
+void virtio_gpu_notify(struct virtio_gpu_device *vgdev)
 {
-	vgdev->disable_notify = true;
-}
-
-void virtio_gpu_enable_notify(struct virtio_gpu_device *vgdev)
-{
-	vgdev->disable_notify = false;
+	bool notify;
 
-	if (!vgdev->pending_notify)
+	if (!atomic_read(&vgdev->pending_commands))
 		return;
-	vgdev->pending_notify = false;
-	virtqueue_notify(vgdev->ctrlq.vq);
+
+	spin_lock(&vgdev->ctrlq.qlock);
+	atomic_set(&vgdev->pending_commands, 0);
+	notify = virtqueue_kick_prepare(vgdev->ctrlq.vq);
+	spin_unlock(&vgdev->ctrlq.qlock);
+
+	if (notify)
+		virtqueue_notify(vgdev->ctrlq.vq);
 }
 
 static void virtio_gpu_queue_ctrl_buffer(struct virtio_gpu_device *vgdev,
 					 struct virtio_gpu_vbuffer *vbuf)
 {
-	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, NULL, NULL);
+	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, NULL);
 }
 
 static void virtio_gpu_queue_cursor(struct virtio_gpu_device *vgdev,
@@ -443,12 +455,13 @@ static void virtio_gpu_queue_cursor(struct virtio_gpu_device *vgdev,
 {
 	struct virtqueue *vq = vgdev->cursorq.vq;
 	struct scatterlist *sgs[1], ccmd;
+	int idx, ret, outcnt;
 	bool notify;
-	int ret;
-	int outcnt;
 
-	if (!vgdev->vqs_ready)
+	if (!drm_dev_enter(vgdev->ddev, &idx)) {
+		free_vbuf(vgdev, vbuf);
 		return;
+	}
 
 	sg_init_one(&ccmd, vbuf->buf, vbuf->size);
 	sgs[0] = &ccmd;
@@ -464,7 +477,7 @@ retry:
 		goto retry;
 	} else {
 		trace_virtio_gpu_cmd_queue(vq,
-			(struct virtio_gpu_ctrl_hdr *)vbuf->buf);
+			virtio_gpu_vbuf_ctrl_hdr(vbuf));
 
 		notify = virtqueue_kick_prepare(vq);
 	}
@@ -473,6 +486,8 @@ retry:
 
 	if (notify)
 		virtqueue_notify(vq);
+
+	drm_dev_exit(idx);
 }
 
 /* just create gem objects for userspace and long lived objects,
@@ -499,39 +514,36 @@ void virtio_gpu_cmd_create_resource(struct virtio_gpu_device *vgdev,
 	cmd_p->width = cpu_to_le32(params->width);
 	cmd_p->height = cpu_to_le32(params->height);
 
-	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, &cmd_p->hdr, fence);
+	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, fence);
 	bo->created = true;
 }
 
-void virtio_gpu_cmd_unref_resource(struct virtio_gpu_device *vgdev,
-				   uint32_t resource_id)
+static void virtio_gpu_cmd_unref_cb(struct virtio_gpu_device *vgdev,
+				    struct virtio_gpu_vbuffer *vbuf)
 {
-	struct virtio_gpu_resource_unref *cmd_p;
-	struct virtio_gpu_vbuffer *vbuf;
+	struct virtio_gpu_object *bo;
 
-	cmd_p = virtio_gpu_alloc_cmd(vgdev, &vbuf, sizeof(*cmd_p));
-	memset(cmd_p, 0, sizeof(*cmd_p));
+	bo = vbuf->resp_cb_data;
+	vbuf->resp_cb_data = NULL;
 
-	cmd_p->hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_RESOURCE_UNREF);
-	cmd_p->resource_id = cpu_to_le32(resource_id);
-
-	virtio_gpu_queue_ctrl_buffer(vgdev, vbuf);
+	virtio_gpu_cleanup_object(bo);
 }
 
-static void virtio_gpu_cmd_resource_inval_backing(struct virtio_gpu_device *vgdev,
-						  uint32_t resource_id,
-						  struct virtio_gpu_fence *fence)
+void virtio_gpu_cmd_unref_resource(struct virtio_gpu_device *vgdev,
+				   struct virtio_gpu_object *bo)
 {
-	struct virtio_gpu_resource_detach_backing *cmd_p;
+	struct virtio_gpu_resource_unref *cmd_p;
 	struct virtio_gpu_vbuffer *vbuf;
 
-	cmd_p = virtio_gpu_alloc_cmd(vgdev, &vbuf, sizeof(*cmd_p));
+	cmd_p = virtio_gpu_alloc_cmd_cb(vgdev, &vbuf, sizeof(*cmd_p),
+					virtio_gpu_cmd_unref_cb);
 	memset(cmd_p, 0, sizeof(*cmd_p));
 
-	cmd_p->hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_RESOURCE_DETACH_BACKING);
-	cmd_p->resource_id = cpu_to_le32(resource_id);
+	cmd_p->hdr.type = cpu_to_le32(VIRTIO_GPU_CMD_RESOURCE_UNREF);
+	cmd_p->resource_id = cpu_to_le32(bo->hw_res_handle);
 
-	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, &cmd_p->hdr, fence);
+	vbuf->resp_cb_data = bo;
+	virtio_gpu_queue_ctrl_buffer(vgdev, vbuf);
 }
 
 void virtio_gpu_cmd_set_scanout(struct virtio_gpu_device *vgdev,
@@ -588,10 +600,11 @@ void virtio_gpu_cmd_transfer_to_host_2d(struct virtio_gpu_device *vgdev,
 	struct virtio_gpu_transfer_to_host_2d *cmd_p;
 	struct virtio_gpu_vbuffer *vbuf;
 	bool use_dma_api = !virtio_has_iommu_quirk(vgdev->vdev);
+	struct virtio_gpu_object_shmem *shmem = to_virtio_gpu_shmem(bo);
 
 	if (use_dma_api)
 		dma_sync_sg_for_device(vgdev->vdev->dev.parent,
-				       bo->pages->sgl, bo->pages->nents,
+				       shmem->pages->sgl, shmem->pages->nents,
 				       DMA_TO_DEVICE);
 
 	cmd_p = virtio_gpu_alloc_cmd(vgdev, &vbuf, sizeof(*cmd_p));
@@ -606,7 +619,7 @@ void virtio_gpu_cmd_transfer_to_host_2d(struct virtio_gpu_device *vgdev,
 	cmd_p->r.x = cpu_to_le32(x);
 	cmd_p->r.y = cpu_to_le32(y);
 
-	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, &cmd_p->hdr, fence);
+	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, fence);
 }
 
 static void
@@ -629,7 +642,7 @@ virtio_gpu_cmd_resource_attach_backing(struct virtio_gpu_device *vgdev,
 	vbuf->data_buf = ents;
 	vbuf->data_size = sizeof(*ents) * nents;
 
-	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, &cmd_p->hdr, fence);
+	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, fence);
 }
 
 static void virtio_gpu_cmd_get_display_info_cb(struct virtio_gpu_device *vgdev,
@@ -939,7 +952,6 @@ void virtio_gpu_cmd_context_attach_resource(struct virtio_gpu_device *vgdev,
 	cmd_p->hdr.ctx_id = cpu_to_le32(ctx_id);
 	cmd_p->resource_id = cpu_to_le32(bo->hw_res_handle);
 	virtio_gpu_queue_ctrl_buffer(vgdev, vbuf);
-
 }
 
 void virtio_gpu_cmd_context_detach_resource(struct virtio_gpu_device *vgdev,
@@ -988,7 +1000,8 @@ virtio_gpu_cmd_resource_create_3d(struct virtio_gpu_device *vgdev,
 	cmd_p->nr_samples = cpu_to_le32(params->nr_samples);
 	cmd_p->flags = cpu_to_le32(params->flags);
 
-	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, &cmd_p->hdr, fence);
+	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, fence);
+
 	bo->created = true;
 }
 
@@ -1003,10 +1016,11 @@ void virtio_gpu_cmd_transfer_to_host_3d(struct virtio_gpu_device *vgdev,
 	struct virtio_gpu_transfer_host_3d *cmd_p;
 	struct virtio_gpu_vbuffer *vbuf;
 	bool use_dma_api = !virtio_has_iommu_quirk(vgdev->vdev);
+	struct virtio_gpu_object_shmem *shmem = to_virtio_gpu_shmem(bo);
 
 	if (use_dma_api)
 		dma_sync_sg_for_device(vgdev->vdev->dev.parent,
-				       bo->pages->sgl, bo->pages->nents,
+				       shmem->pages->sgl, shmem->pages->nents,
 				       DMA_TO_DEVICE);
 
 	cmd_p = virtio_gpu_alloc_cmd(vgdev, &vbuf, sizeof(*cmd_p));
@@ -1021,7 +1035,7 @@ void virtio_gpu_cmd_transfer_to_host_3d(struct virtio_gpu_device *vgdev,
 	cmd_p->offset = cpu_to_le64(offset);
 	cmd_p->level = cpu_to_le32(level);
 
-	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, &cmd_p->hdr, fence);
+	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, fence);
 }
 
 void virtio_gpu_cmd_transfer_from_host_3d(struct virtio_gpu_device *vgdev,
@@ -1047,7 +1061,7 @@ void virtio_gpu_cmd_transfer_from_host_3d(struct virtio_gpu_device *vgdev,
 	cmd_p->offset = cpu_to_le64(offset);
 	cmd_p->level = cpu_to_le32(level);
 
-	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, &cmd_p->hdr, fence);
+	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, fence);
 }
 
 void virtio_gpu_cmd_submit(struct virtio_gpu_device *vgdev,
@@ -1070,94 +1084,19 @@ void virtio_gpu_cmd_submit(struct virtio_gpu_device *vgdev,
 	cmd_p->hdr.ctx_id = cpu_to_le32(ctx_id);
 	cmd_p->size = cpu_to_le32(data_size);
 
-	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, &cmd_p->hdr, fence);
+	virtio_gpu_queue_fenced_ctrl_buffer(vgdev, vbuf, fence);
 }
 
 int virtio_gpu_object_attach(struct virtio_gpu_device *vgdev,
 			     struct virtio_gpu_object *obj,
-			     struct virtio_gpu_fence *fence)
+			     struct virtio_gpu_mem_entry *ents,
+			     unsigned int nents)
 {
-	bool use_dma_api = !virtio_has_iommu_quirk(vgdev->vdev);
-	struct virtio_gpu_mem_entry *ents;
-	struct scatterlist *sg;
-	int si, nents, ret;
-
-	if (WARN_ON_ONCE(!obj->created))
-		return -EINVAL;
-	if (WARN_ON_ONCE(obj->pages))
-		return -EINVAL;
-
-	ret = drm_gem_shmem_pin(&obj->base.base);
-	if (ret < 0)
-		return -EINVAL;
-
-	obj->pages = drm_gem_shmem_get_sg_table(&obj->base.base);
-	if (obj->pages == NULL) {
-		drm_gem_shmem_unpin(&obj->base.base);
-		return -EINVAL;
-	}
-
-	if (use_dma_api) {
-		obj->mapped = dma_map_sg(vgdev->vdev->dev.parent,
-					 obj->pages->sgl, obj->pages->nents,
-					 DMA_TO_DEVICE);
-		nents = obj->mapped;
-	} else {
-		nents = obj->pages->nents;
-	}
-
-	/* gets freed when the ring has consumed it */
-	ents = kmalloc_array(nents, sizeof(struct virtio_gpu_mem_entry),
-			     GFP_KERNEL);
-	if (!ents) {
-		DRM_ERROR("failed to allocate ent list\n");
-		return -ENOMEM;
-	}
-
-	for_each_sg(obj->pages->sgl, sg, nents, si) {
-		ents[si].addr = cpu_to_le64(use_dma_api
-					    ? sg_dma_address(sg)
-					    : sg_phys(sg));
-		ents[si].length = cpu_to_le32(sg->length);
-		ents[si].padding = 0;
-	}
-
 	virtio_gpu_cmd_resource_attach_backing(vgdev, obj->hw_res_handle,
-					       ents, nents,
-					       fence);
+					       ents, nents, NULL);
 	return 0;
 }
 
-void virtio_gpu_object_detach(struct virtio_gpu_device *vgdev,
-			      struct virtio_gpu_object *obj)
-{
-	bool use_dma_api = !virtio_has_iommu_quirk(vgdev->vdev);
-
-	if (WARN_ON_ONCE(!obj->pages))
-		return;
-
-	if (use_dma_api && obj->mapped) {
-		struct virtio_gpu_fence *fence = virtio_gpu_fence_alloc(vgdev);
-		/* detach backing and wait for the host process it ... */
-		virtio_gpu_cmd_resource_inval_backing(vgdev, obj->hw_res_handle, fence);
-		dma_fence_wait(&fence->f, true);
-		dma_fence_put(&fence->f);
-
-		/* ... then tear down iommu mappings */
-		dma_unmap_sg(vgdev->vdev->dev.parent,
-			     obj->pages->sgl, obj->mapped,
-			     DMA_TO_DEVICE);
-		obj->mapped = 0;
-	} else {
-		virtio_gpu_cmd_resource_inval_backing(vgdev, obj->hw_res_handle, NULL);
-	}
-
-	sg_free_table(obj->pages);
-	obj->pages = NULL;
-
-	drm_gem_shmem_unpin(&obj->base.base);
-}
-
 void virtio_gpu_cursor_ping(struct virtio_gpu_device *vgdev,
 			    struct virtio_gpu_output *output)
 {