Re: [PATCH v5 11/16] rpmsg: virtio: register the rpmsg_ctrl device

From: Mathieu Poirier
Date: Wed Mar 03 2021 - 14:18:13 EST


On Fri, Feb 19, 2021 at 12:14:56PM +0100, Arnaud Pouliquen wrote:
> Instantiate the rpmsg_ioctl device on virtio RPMsg bus creation.

s/rpmsg_ioctl/rpmsg_ctrl

Now I understand what you meant in patch 05.

> This provides the possibility to expose the RPMSG_CREATE_EPT_IOCTL
> to create RPMsg chdev endpoints.

You mean RPMSG device endpoints, i.e rpmsg_eptdev? If so I think it should be
added to the changelog. Otherwiser someone could be tempted to look for "chdev"
and find anything but a rpmsg_eptdev.

>
> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
>
> ---
> V5:
> Fix compilation issue
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> ---
> drivers/rpmsg/virtio_rpmsg_bus.c | 57 +++++++++++++++++++++++++++++---
> 1 file changed, 52 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
> index e87d4cf926eb..2e6b34084012 100644
> --- a/drivers/rpmsg/virtio_rpmsg_bus.c
> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c
> @@ -813,14 +813,52 @@ static void rpmsg_xmit_done(struct virtqueue *svq)
> wake_up_interruptible(&vrp->sendq);
> }
>
> +static struct rpmsg_device *rpmsg_virtio_add_ctrl_dev(struct virtio_device *vdev)
> +{
> + struct virtproc_info *vrp = vdev->priv;
> + struct virtio_rpmsg_channel *vch;
> + struct rpmsg_device *rpdev_ctrl;
> + int err = 0;
> +
> + vch = kzalloc(sizeof(*vch), GFP_KERNEL);
> + if (!vch)
> + return ERR_PTR(-ENOMEM);
> +
> + /* Link the channel to the vrp */
> + vch->vrp = vrp;
> +
> + /* Assign public information to the rpmsg_device */
> + rpdev_ctrl = &vch->rpdev;
> + rpdev_ctrl->ops = &virtio_rpmsg_ops;
> +
> + rpdev_ctrl->dev.parent = &vrp->vdev->dev;
> + rpdev_ctrl->dev.release = virtio_rpmsg_release_device;
> + rpdev_ctrl->little_endian = virtio_is_little_endian(vrp->vdev);
> +
> + err = rpmsg_ctrl_register_device(rpdev_ctrl);
> + if (err) {
> + kfree(vch);
> + return ERR_PTR(err);
> + }
> +
> + return rpdev_ctrl;
> +}
> +
> +static void rpmsg_virtio_del_ctrl_dev(struct rpmsg_device *rpdev_ctrl)
> +{
> + if (!rpdev_ctrl)
> + return;
> + kfree(to_virtio_rpmsg_channel(rpdev_ctrl));
> +}
> +
> static int rpmsg_probe(struct virtio_device *vdev)
> {
> vq_callback_t *vq_cbs[] = { rpmsg_recv_done, rpmsg_xmit_done };
> static const char * const names[] = { "input", "output" };
> struct virtqueue *vqs[2];
> struct virtproc_info *vrp;
> - struct virtio_rpmsg_channel *vch;
> - struct rpmsg_device *rpdev_ns;
> + struct virtio_rpmsg_channel *vch = NULL;
> + struct rpmsg_device *rpdev_ns = NULL, *rpdev_ctrl;

As far as I can tell @rpdev_ns doesn't have to be initialized.

> void *bufs_va;
> int err = 0, i;
> size_t total_buf_space;
> @@ -894,12 +932,18 @@ static int rpmsg_probe(struct virtio_device *vdev)
>
> vdev->priv = vrp;
>
> + rpdev_ctrl = rpmsg_virtio_add_ctrl_dev(vdev);
> + if (IS_ERR(rpdev_ctrl)) {
> + err = PTR_ERR(rpdev_ctrl);
> + goto free_coherent;
> + }
> +
> /* if supported by the remote processor, enable the name service */
> if (virtio_has_feature(vdev, VIRTIO_RPMSG_F_NS)) {
> vch = kzalloc(sizeof(*vch), GFP_KERNEL);
> if (!vch) {
> err = -ENOMEM;
> - goto free_coherent;
> + goto free_ctrldev;
> }
>
> /* Link the channel to our vrp */
> @@ -915,7 +959,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
>
> err = rpmsg_ns_register_device(rpdev_ns);
> if (err)
> - goto free_coherent;
> + goto free_vch;
> }
>
> /*
> @@ -939,8 +983,11 @@ static int rpmsg_probe(struct virtio_device *vdev)
>
> return 0;
>
> -free_coherent:
> +free_vch:
> kfree(vch);
> +free_ctrldev:
> + rpmsg_virtio_del_ctrl_dev(rpdev_ctrl);
> +free_coherent:
> dma_free_coherent(vdev->dev.parent, total_buf_space,
> bufs_va, vrp->bufs_dma);
> vqs_del:
> --
> 2.17.1
>