| Message ID | 20240328083615.2662516-5-vivek.kasireddy@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/virtio: Import scanout buffers from other devices | expand |
On Thu, Mar 28, 2024 at 01:32:57AM -0700, Vivek Kasireddy wrote: > By importing scanout buffers from other devices, we should be able > to use the virtio-gpu driver in KMS only mode. Note that we attach > dynamically and register a move_notify() callback so that we can > let the VMM know of any location changes associated with the backing > store of the imported object by sending detach_backing cmd. > > Cc: Gerd Hoffmann <kraxel@redhat.com> > Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com> > --- > drivers/gpu/drm/virtio/virtgpu_prime.c | 54 +++++++++++++++++++++++++- > 1 file changed, 53 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/virtio/virtgpu_prime.c b/drivers/gpu/drm/virtio/virtgpu_prime.c > index 1e87dbc9a897..c65dacc1b2b5 100644 > --- a/drivers/gpu/drm/virtio/virtgpu_prime.c > +++ b/drivers/gpu/drm/virtio/virtgpu_prime.c > @@ -255,10 +255,36 @@ static int virtgpu_dma_buf_init_obj(struct drm_device *dev, > return ret; > } > > +static const struct drm_gem_object_funcs virtgpu_gem_dma_buf_funcs = { > + .free = virtgpu_dma_buf_free_obj, > +}; > + > +static void virtgpu_dma_buf_move_notify(struct dma_buf_attachment *attach) > +{ > + struct drm_gem_object *obj = attach->importer_priv; > + struct virtio_gpu_device *vgdev = obj->dev->dev_private; > + struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj); > + > + if (bo->created) { > + virtio_gpu_cmd_resource_detach_backing(vgdev, > + bo->hw_res_handle); > + bo->has_backing = false; > + } > +} > + > +static const struct dma_buf_attach_ops virtgpu_dma_buf_attach_ops = { > + .allow_peer2peer = true, > + .move_notify = virtgpu_dma_buf_move_notify > +}; > + > struct drm_gem_object *virtgpu_gem_prime_import(struct drm_device *dev, > struct dma_buf *buf) > { > + struct virtio_gpu_device *vgdev = dev->dev_private; > + struct dma_buf_attachment *attach; > + struct virtio_gpu_object *bo; > struct drm_gem_object *obj; > + int ret; > > if (buf->ops == &virtgpu_dmabuf_ops.ops) { > obj = buf->priv; > @@ -272,7 +298,32 @@ struct drm_gem_object *virtgpu_gem_prime_import(struct drm_device *dev, > } > } > > - return drm_gem_prime_import(dev, buf); I think overall this (entire series) makes sense, but needs someone with overall virtio understanding to make sure it all fits correctly. Just a refactor thought here: I think instead of open-coding should we have a drm_gem_prime_dynamic_import? Similar in another patch for the dma_buf_pin, should that be also in the gem helpers to automatically forward to dma_buf if it's imported? Cheers, Sima > + if (!vgdev->has_resource_blob || vgdev->has_virgl_3d) > + return drm_gem_prime_import(dev, buf); > + > + bo = kzalloc(sizeof(*bo), GFP_KERNEL); > + if (!bo) > + return ERR_PTR(-ENOMEM); > + > + obj = &bo->base.base; > + obj->funcs = &virtgpu_gem_dma_buf_funcs; > + drm_gem_private_object_init(dev, obj, buf->size); > + > + attach = dma_buf_dynamic_attach(buf, dev->dev, > + &virtgpu_dma_buf_attach_ops, obj); > + if (IS_ERR(attach)) { > + kfree(bo); > + return ERR_CAST(attach); > + } > + > + obj->import_attach = attach; > + get_dma_buf(buf); > + > + ret = virtgpu_dma_buf_init_obj(dev, bo, attach); > + if (ret < 0) > + return ERR_PTR(ret); > + > + return obj; > } > > struct drm_gem_object *virtgpu_gem_prime_import_sg_table( > @@ -281,3 +332,4 @@ struct drm_gem_object *virtgpu_gem_prime_import_sg_table( > { > return ERR_PTR(-ENODEV); > } > + > -- > 2.43.0 >
diff --git a/drivers/gpu/drm/virtio/virtgpu_prime.c b/drivers/gpu/drm/virtio/virtgpu_prime.c index 1e87dbc9a897..c65dacc1b2b5 100644 --- a/drivers/gpu/drm/virtio/virtgpu_prime.c +++ b/drivers/gpu/drm/virtio/virtgpu_prime.c @@ -255,10 +255,36 @@ static int virtgpu_dma_buf_init_obj(struct drm_device *dev, return ret; } +static const struct drm_gem_object_funcs virtgpu_gem_dma_buf_funcs = { + .free = virtgpu_dma_buf_free_obj, +}; + +static void virtgpu_dma_buf_move_notify(struct dma_buf_attachment *attach) +{ + struct drm_gem_object *obj = attach->importer_priv; + struct virtio_gpu_device *vgdev = obj->dev->dev_private; + struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(obj); + + if (bo->created) { + virtio_gpu_cmd_resource_detach_backing(vgdev, + bo->hw_res_handle); + bo->has_backing = false; + } +} + +static const struct dma_buf_attach_ops virtgpu_dma_buf_attach_ops = { + .allow_peer2peer = true, + .move_notify = virtgpu_dma_buf_move_notify +}; + struct drm_gem_object *virtgpu_gem_prime_import(struct drm_device *dev, struct dma_buf *buf) { + struct virtio_gpu_device *vgdev = dev->dev_private; + struct dma_buf_attachment *attach; + struct virtio_gpu_object *bo; struct drm_gem_object *obj; + int ret; if (buf->ops == &virtgpu_dmabuf_ops.ops) { obj = buf->priv; @@ -272,7 +298,32 @@ struct drm_gem_object *virtgpu_gem_prime_import(struct drm_device *dev, } } - return drm_gem_prime_import(dev, buf); + if (!vgdev->has_resource_blob || vgdev->has_virgl_3d) + return drm_gem_prime_import(dev, buf); + + bo = kzalloc(sizeof(*bo), GFP_KERNEL); + if (!bo) + return ERR_PTR(-ENOMEM); + + obj = &bo->base.base; + obj->funcs = &virtgpu_gem_dma_buf_funcs; + drm_gem_private_object_init(dev, obj, buf->size); + + attach = dma_buf_dynamic_attach(buf, dev->dev, + &virtgpu_dma_buf_attach_ops, obj); + if (IS_ERR(attach)) { + kfree(bo); + return ERR_CAST(attach); + } + + obj->import_attach = attach; + get_dma_buf(buf); + + ret = virtgpu_dma_buf_init_obj(dev, bo, attach); + if (ret < 0) + return ERR_PTR(ret); + + return obj; } struct drm_gem_object *virtgpu_gem_prime_import_sg_table( @@ -281,3 +332,4 @@ struct drm_gem_object *virtgpu_gem_prime_import_sg_table( { return ERR_PTR(-ENODEV); } +
By importing scanout buffers from other devices, we should be able to use the virtio-gpu driver in KMS only mode. Note that we attach dynamically and register a move_notify() callback so that we can let the VMM know of any location changes associated with the backing store of the imported object by sending detach_backing cmd. Cc: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com> --- drivers/gpu/drm/virtio/virtgpu_prime.c | 54 +++++++++++++++++++++++++- 1 file changed, 53 insertions(+), 1 deletion(-)