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From:   "Liu, Yi L" <yi.l.liu@intel.com>
To:     David Gibson <david@gibson.dropbear.id.au>
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Subject: RE: [RFC 02/20] vfio: Add device class for /dev/vfio/devices
Thread-Topic: [RFC 02/20] vfio: Add device class for /dev/vfio/devices
Thread-Index: AQHXrSFuEUBAJXc9I0mCP8LXFMJv/au6U6uAgCGxC2A=
Date:   Wed, 20 Oct 2021 12:39:49 +0000
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References: <20210919063848.1476776-1-yi.l.liu@intel.com>
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> From: David Gibson <david@gibson.dropbear.id.au>
> Sent: Wednesday, September 29, 2021 10:09 AM
>=20
> On Sun, Sep 19, 2021 at 02:38:30PM +0800, Liu Yi L wrote:
> > This patch introduces a new interface (/dev/vfio/devices/$DEVICE) for
> > userspace to directly open a vfio device w/o relying on container/group
> > (/dev/vfio/$GROUP). Anything related to group is now hidden behind
> > iommufd (more specifically in iommu core by this RFC) in a device-centr=
ic
> > manner.
> >
> > In case a device is exposed in both legacy and new interfaces (see next
> > patch for how to decide it), this patch also ensures that when the devi=
ce
> > is already opened via one interface then the other one must be blocked.
> >
> > Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
> [snip]
>=20
> > +static bool vfio_device_in_container(struct vfio_device *device)
> > +{
> > +	return !!(device->group && device->group->container);
>=20
> You don't need !! here.  && is already a logical operation, so returns
> a valid bool.

got it. thanks.

Regards,
Yi Liu