Re: [Qemu-devel] [PATCH v13 02/22] vfio: VFIO based driver for Mediated devices

[Dong Jia Shi]

* Kirti Wankhede <address@hidden> [2016-11-15 20:59:45 +0530]:

Hi Kirti,

> vfio_mdev driver registers with mdev core driver.
> mdev core driver creates mediated device and calls probe routine of
> vfio_mdev driver for each device.
> Probe routine of vfio_mdev driver adds mediated device to VFIO core module
> 
> This driver forms a shim layer that pass through VFIO devices operations
> to vendor driver for mediated devices.
> 
> Signed-off-by: Kirti Wankhede <address@hidden>
> Signed-off-by: Neo Jia <address@hidden>
> Reviewed-by: Jike Song <address@hidden>
> 
> Change-Id: I583f4734752971d3d112324d69e2508c88f359ec
> ---
>  drivers/vfio/mdev/Kconfig     |   7 ++
>  drivers/vfio/mdev/Makefile    |   1 +
>  drivers/vfio/mdev/mdev_core.c |  16 ++++-
>  drivers/vfio/mdev/vfio_mdev.c | 148 
> ++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 171 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/vfio/mdev/vfio_mdev.c
> 
> diff --git a/drivers/vfio/mdev/Kconfig b/drivers/vfio/mdev/Kconfig
> index 258481d65ebd..1aa0391d74f2 100644
> --- a/drivers/vfio/mdev/Kconfig
> +++ b/drivers/vfio/mdev/Kconfig
> @@ -7,3 +7,10 @@ config VFIO_MDEV
>         Provides a framework to virtualize devices.
> 
>         If you don't know what do here, say N.
> +
> +config VFIO_MDEV_DEVICE
> +     tristate "VFIO support for Mediated devices"
                                   ^^^^^^^^^^^^^^^^

> +     depends on VFIO && VFIO_MDEV
> +     default n
> +     help
> +       VFIO based driver for mediated devices.
                                ^^^^^^^^^^^^^^^^
nit:
s/mediated/Mediated/

I saw in many places you use the term "Mediated device", so I guess this
is what you preferred to name them.

> diff --git a/drivers/vfio/mdev/Makefile b/drivers/vfio/mdev/Makefile
> index 31bc04801d94..fa2d5ea466ee 100644
> --- a/drivers/vfio/mdev/Makefile
> +++ b/drivers/vfio/mdev/Makefile
> @@ -2,3 +2,4 @@
>  mdev-y := mdev_core.o mdev_sysfs.o mdev_driver.o
> 
>  obj-$(CONFIG_VFIO_MDEV) += mdev.o
> +obj-$(CONFIG_VFIO_MDEV_DEVICE) += vfio_mdev.o
> diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
> index 613e8a8a3b2a..1e0714ebc56a 100644
> --- a/drivers/vfio/mdev/mdev_core.c
> +++ b/drivers/vfio/mdev/mdev_core.c
> @@ -354,7 +354,21 @@ int mdev_device_remove(struct device *dev, bool 
> force_remove)
> 
>  static int __init mdev_init(void)
>  {
> -     return mdev_bus_register();
> +     int ret;
> +
> +     ret = mdev_bus_register();
> +     if (ret) {
> +             pr_err("Failed to register mdev bus\n");
If you want to report an error message here, you should do it in a
previous patch where you introduce the call for mdev_bus_register.

> +             return ret;
> +     }
> +
> +     /*
> +      * Attempt to load known vfio_mdev.  This gives us a working environment
> +      * without the user needing to explicitly load vfio_mdev driver.
> +      */
> +     request_module_nowait("vfio_mdev");
> +
> +     return ret;
>  }
> 
>  static void __exit mdev_exit(void)
[...]

Please:
Reviewed-by: Dong Jia Shi <address@hidden>

-- 
Dong Jia