On Tue, Sep 08, 2020 at 08:47:41AM +0200, Gerd Hoffmann wrote:
> These days dma ops can be overridden per device, and the virtio core
"can be overridden" or "are"? The comment above vring_use_dma_api()
suggests that's not yet done. If that's wrong then I think updating the
comment would be really good.
-Daniel
> uses that to handle the dma quirks transparently for the rest of the
> kernel. So we can drop the virtio_has_dma_quirk() checks, just use
> the dma api unconditionally and depend on the virtio core having setup
> dma_ops as needed.
>
> Signed-off-by: Gerd Hoffmann <kra...@redhat.com>
> ---
> drivers/gpu/drm/virtio/virtgpu_object.c | 19 ++++++-------------
> drivers/gpu/drm/virtio/virtgpu_vq.c | 16 ++++++----------
> 2 files changed, 12 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/gpu/drm/virtio/virtgpu_object.c
> b/drivers/gpu/drm/virtio/virtgpu_object.c
> index 729f98ad7c02..9c35ce64ff9e 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_object.c
> +++ b/drivers/gpu/drm/virtio/virtgpu_object.c
> @@ -141,7 +141,6 @@ static int virtio_gpu_object_shmem_init(struct
> virtio_gpu_device *vgdev,
> struct virtio_gpu_mem_entry **ents,
> unsigned int *nents)
> {
> - bool use_dma_api = !virtio_has_dma_quirk(vgdev->vdev);
> struct virtio_gpu_object_shmem *shmem = to_virtio_gpu_shmem(bo);
> struct scatterlist *sg;
> int si, ret;
> @@ -162,15 +161,11 @@ static int virtio_gpu_object_shmem_init(struct
> virtio_gpu_device *vgdev,
> return -EINVAL;
> }
>
> - if (use_dma_api) {
> - shmem->mapped = dma_map_sg(vgdev->vdev->dev.parent,
> - shmem->pages->sgl,
> - shmem->pages->nents,
> - DMA_TO_DEVICE);
> - *nents = shmem->mapped;
> - } else {
> - *nents = shmem->pages->nents;
> - }
> + shmem->mapped = dma_map_sg(vgdev->vdev->dev.parent,
> + shmem->pages->sgl,
> + shmem->pages->nents,
> + DMA_TO_DEVICE);
> + *nents = shmem->mapped;
>
> *ents = kmalloc_array(*nents, sizeof(struct virtio_gpu_mem_entry),
> GFP_KERNEL);
> @@ -180,9 +175,7 @@ static int virtio_gpu_object_shmem_init(struct
> virtio_gpu_device *vgdev,
> }
>
> for_each_sg(shmem->pages->sgl, sg, *nents, si) {
> - (*ents)[si].addr = cpu_to_le64(use_dma_api
> - ? sg_dma_address(sg)
> - : sg_phys(sg));
> + (*ents)[si].addr = cpu_to_le64(sg_dma_address(sg));
> (*ents)[si].length = cpu_to_le32(sg->length);
> (*ents)[si].padding = 0;
> }
> diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c
> b/drivers/gpu/drm/virtio/virtgpu_vq.c
> index c93c2db35aaf..1c1d2834547d 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_vq.c
> +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
> @@ -599,13 +599,11 @@ void virtio_gpu_cmd_transfer_to_host_2d(struct
> virtio_gpu_device *vgdev,
> struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(objs->objs[0]);
> struct virtio_gpu_transfer_to_host_2d *cmd_p;
> struct virtio_gpu_vbuffer *vbuf;
> - bool use_dma_api = !virtio_has_dma_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,
> - shmem->pages->sgl, shmem->pages->nents,
> - DMA_TO_DEVICE);
> + dma_sync_sg_for_device(vgdev->vdev->dev.parent,
> + shmem->pages->sgl, shmem->pages->nents,
> + DMA_TO_DEVICE);
>
> cmd_p = virtio_gpu_alloc_cmd(vgdev, &vbuf, sizeof(*cmd_p));
> memset(cmd_p, 0, sizeof(*cmd_p));
> @@ -1015,13 +1013,11 @@ void virtio_gpu_cmd_transfer_to_host_3d(struct
> virtio_gpu_device *vgdev,
> struct virtio_gpu_object *bo = gem_to_virtio_gpu_obj(objs->objs[0]);
> struct virtio_gpu_transfer_host_3d *cmd_p;
> struct virtio_gpu_vbuffer *vbuf;
> - bool use_dma_api = !virtio_has_dma_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,
> - shmem->pages->sgl, shmem->pages->nents,
> - DMA_TO_DEVICE);
> + dma_sync_sg_for_device(vgdev->vdev->dev.parent,
> + shmem->pages->sgl, shmem->pages->nents,
> + DMA_TO_DEVICE);
>
> cmd_p = virtio_gpu_alloc_cmd(vgdev, &vbuf, sizeof(*cmd_p));
> memset(cmd_p, 0, sizeof(*cmd_p));
> --
> 2.27.0
>
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
