Re: [PATCH v9 02/17] qdev: unplug blocker for devices

[Markus Armbruster <armbru@redhat.com>]

Jagannathan Raman <jag.raman@oracle.com> writes:

> Add blocker to prevent hot-unplug of devices
>
> TYPE_VFIO_USER_SERVER, which is introduced shortly, attaches itself to a
> PCIDevice on which it depends. If the attached PCIDevice gets removed
> while the server in use, it could cause it crash. To prevent this,
> TYPE_VFIO_USER_SERVER adds an unplug blocker for the PCIDevice.

Appreciate the explanation :)

>
> Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
> Signed-off-by: John G Johnson <john.g.johnson@oracle.com>
> Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
> ---
>  include/hw/qdev-core.h | 29 +++++++++++++++++++++++++++++
>  hw/core/qdev.c         | 24 ++++++++++++++++++++++++
>  softmmu/qdev-monitor.c |  4 ++++
>  3 files changed, 57 insertions(+)
>
> diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h
> index 92c3d65208..1b9fa25e5c 100644
> --- a/include/hw/qdev-core.h
> +++ b/include/hw/qdev-core.h
> @@ -193,6 +193,7 @@ struct DeviceState {
>      int instance_id_alias;
>      int alias_required_for_version;
>      ResettableState reset;
> +    GSList *unplug_blockers;
>  };
>  
>  struct DeviceListener {
> @@ -419,6 +420,34 @@ void qdev_simple_device_unplug_cb(HotplugHandler *hotplug_dev,
>  void qdev_machine_creation_done(void);
>  bool qdev_machine_modified(void);
>  
> +/*

Use /** here like we do in the other function comments nearby.

In case you're curious: it's GTK-Doc format.  It's intended for
generating documentation from doc comments.  Which we don't do, and
perhaps never will.  But let's be locally consistent.

> + * qdev_add_unplug_blocker: Adds an unplug blocker to a device

Recommend imperative mood for function comments: "Add an unplug
blocker to a device".

More of the same below.

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