Re: [PATCH v2 10/16] rpmsg: char: allow only one endpoint per device

From: Bjorn Andersson
Date: Mon Jan 04 2021 - 20:00:41 EST


On Tue 22 Dec 04:57 CST 2020, Arnaud Pouliquen wrote:

> Only one endpoint can be created per device, prevent from multi open.
>

Having multiple invocations of rpmsg_create_ept() with the same chinfo
sounds like a bad idea. I think in the SMD and GLINK case the underlying
transport would complain that the related chinfo is already "busy", but
this seems like an appropriate fix regardless.

Please add a proper Fixes: tag and send this outside of this patch
series.

Thanks,
Bjorn

> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
> ---
> drivers/rpmsg/rpmsg_char.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c
> index 66e01b979e72..4b0674a2e3e9 100644
> --- a/drivers/rpmsg/rpmsg_char.c
> +++ b/drivers/rpmsg/rpmsg_char.c
> @@ -122,6 +122,9 @@ static int rpmsg_eptdev_open(struct inode *inode, struct file *filp)
> struct rpmsg_device *rpdev = eptdev->rpdev;
> struct device *dev = &eptdev->dev;
>
> + if (eptdev->ept)
> + return -EBUSY;
> +
> get_device(dev);
>
> ept = rpmsg_create_ept(rpdev, rpmsg_ept_cb, eptdev, eptdev->chinfo);
> --
> 2.17.1
>