Re: [RFC v2 1/3] virtio: add vhost-user-fs-ccw device

[Halil Pasic <pasic@linux.ibm.com>]

On Tue, 28 Jul 2020 12:31:51 +0200
Cornelia Huck <cohuck@redhat.com> wrote:

> On Fri, 17 Jul 2020 11:29:27 +0200
> Marc Hartmayer <mhartmay@linux.ibm.com> wrote:
> 
> > From: Halil Pasic <pasic@linux.ibm.com>
> > 
> > Wire up the CCW device for vhost-user-fs.
> > 
> > Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
> > ---
> >  hw/s390x/Makefile.objs       |  1 +
> >  hw/s390x/vhost-user-fs-ccw.c | 73 ++++++++++++++++++++++++++++++++++++
> >  2 files changed, 74 insertions(+)
> >  create mode 100644 hw/s390x/vhost-user-fs-ccw.c
> > 
> 
> (...)
> 
> > diff --git a/hw/s390x/vhost-user-fs-ccw.c b/hw/s390x/vhost-user-fs-ccw.c
> > new file mode 100644
> > index 000000000000..88a7a11a34b4
> > --- /dev/null
> > +++ b/hw/s390x/vhost-user-fs-ccw.c
> > @@ -0,0 +1,73 @@
> > +/*
> > + * Ccw transport wiring for vhost-user-fs
> 
> "virtio ccw vhost-user-fs implementation" ?
> 

Nod.

> > + *
> > + * Copyright 2020 IBM Corp.
> > + *
> > + * This work is licensed under the terms of the GNU GPL, version 2 or (at
> > + * your option) any later version. See the COPYING file in the top-level
> > + * directory.
> > + */
> > +#include "qemu/osdep.h"
> > +#include "hw/qdev-properties.h"
> > +#include "qapi/error.h"
> > +#include "hw/virtio/vhost-user-fs.h"
> > +#include "virtio-ccw.h"
> > +
> > +typedef struct VHostUserFSCcw {
> > +    VirtioCcwDevice parent_obj;
> > +    VHostUserFS vdev;
> > +} VHostUserFSCcw;
> > +
> > +#define TYPE_VHOST_USER_FS_CCW "vhost-user-fs-ccw"
> > +#define VHOST_USER_FS_CCW(obj) \
> > +        OBJECT_CHECK(VHostUserFSCcw, (obj), TYPE_VHOST_USER_FS_CCW)
> > +
> > +
> > +static Property vhost_user_fs_ccw_properties[] = {
> > +    DEFINE_PROP_BIT("ioeventfd", VirtioCcwDevice, flags,
> > +                    VIRTIO_CCW_FLAG_USE_IOEVENTFD_BIT, true),
> > +    DEFINE_PROP_UINT32("max_revision", VirtioCcwDevice, max_rev,
> > +                       VIRTIO_CCW_MAX_REV),
> > +    DEFINE_PROP_END_OF_LIST(),
> > +};
> > +
> > +static void vhost_user_fs_ccw_realize(VirtioCcwDevice *ccw_dev, Error **errp)
> > +{
> > +    VHostUserFSCcw *dev = VHOST_USER_FS_CCW(ccw_dev);
> > +    DeviceState *vdev = DEVICE(&dev->vdev);
> > +
> > +    qdev_realize(vdev, BUS(&ccw_dev->bus), errp);
> > +}
> > +
> > +static void vhost_user_fs_ccw_instance_init(Object *obj)
> > +{
> > +    VHostUserFSCcw *dev = VHOST_USER_FS_CCW(obj);
> > +
> 
> This needs
> 
>     ccw_dev->force_revision_1 = true;
> 

I'm OK with that as well. Just out of curiosity, why do we need it? Is
there a virtio-ccw revision 1 feature this device inherently needs?

Regards,
Halil

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