Re: [PATCH v7 16/46] virtio_blk: v1.0 support

Cornelia Huck
2014-12-01T11:28:58Z

On Mon, 1 Dec 2014 11:01:36 +0100
David Hildenbrand <dahi@linux.vnet.ibm.com> wrote:

> > On Mon, Dec 01, 2014 at 09:16:41AM +0100, David Hildenbrand wrote:
> > > > Based on patch by Cornelia Huck.
> > > >
> > > > Note: for consistency, and to avoid sparse errors,
> > > > convert all fields, even those no longer in use
> > > > for virtio v1.0.
> > > >
> > > > Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
> > > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> > > ...
> > > >
> > > > -static unsigned int features[] = {
> > > > +static unsigned int features_legacy[] = {
> > > > VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY,
> > > > VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, VIRTIO_BLK_F_SCSI,
> > > > VIRTIO_BLK_F_WCE, VIRTIO_BLK_F_TOPOLOGY, VIRTIO_BLK_F_CONFIG_WCE,
> > > > VIRTIO_BLK_F_MQ,
> > > > +}
> > > > +;
> > > > +static unsigned int features[] = {
> > > > + VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY,
> > > > + VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE,
> > > > + VIRTIO_BLK_F_TOPOLOGY,
> > > > + VIRTIO_BLK_F_MQ,
> > > > + VIRTIO_F_VERSION_1,
> > >
> > > We can fit this into less lines, like done for features_legacy.
> >
> > Wrt packing code more tightly, I did it like this to
> > make it easier to compare the arrays.
> > Each flag is on the same line in original and new array.
>
> This just looks inconsistent to me.
>
> 1. features_legacy is tightly packed
> 2. half of features is tightly packed
>
> So either all tightly packed or put every item on a single line. At least
> that's what I would do :)

I agree with the reasoning that this makes it easy to compare legacy
vs. standard at a glance, so I vote for keeping it this way.