Re: [PATCH v3 11/14] s390: vfio-ap: sysfs interface to view matrix mdev matrix

[Pierre Morel]

On 15/03/2018 15:52, Tony Krowiak wrote:
> On 03/15/2018 05:42 AM, Pierre Morel wrote:
> > On 14/03/2018 19:25, Tony Krowiak wrote:
> > > Provides a sysfs interface to view the AP matrix configured for the
> > > mediated matrix device.
> > >
> > > The relevant sysfs structures are:
> > >
> > > /sys/devices/vfio_ap
> > > ... [matrix]
> > > ...... [mdev_supported_types]
> > > ......... [vfio_ap-passthrough]
> > > ............ [devices]
> > > ...............[$uuid]
> > > .................. matrix
> > >
> > > To view the matrix configured for the mediated matrix device,
> > > print the matrix file:
> > >
> > > ÂÂÂ cat matrix
> > >
> > > Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx>
> > > ---
> > > Â drivers/s390/crypto/vfio_ap_ops.c |ÂÂ 39 
> > > +++++++++++++++++++++++++++++++++++++
> > > Â 1 files changed, 39 insertions(+), 0 deletions(-)
> > >
> > > diff --git a/drivers/s390/crypto/vfio_ap_ops.c 
> > > b/drivers/s390/crypto/vfio_ap_ops.c
> > > index 461d450..04f7a92 100644
> > > --- a/drivers/s390/crypto/vfio_ap_ops.c
> > > +++ b/drivers/s390/crypto/vfio_ap_ops.c
> > > @@ -692,6 +692,44 @@ static ssize_t control_domains_show(struct 
> > > device *dev,
> > > Â }
> > > Â DEVICE_ATTR_RO(control_domains);
> > >
> > > +static ssize_t matrix_show(struct device *dev, struct 
> > > device_attribute *attr,
> > > +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂ char *buf)
> > > +{
> > > +ÂÂÂ struct mdev_device *mdev = mdev_from_dev(dev);
> > > +ÂÂÂ struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev);
> > > +ÂÂÂ char *bufpos = buf;
> > > +ÂÂÂ unsigned long apid;
> > > +ÂÂÂ unsigned long apqi;
> > > +ÂÂÂ int nchars = 0;
> > > +ÂÂÂ int n;
> > > +
> > > +ÂÂÂ n = sprintf(bufpos, "ADAPTER.DOMAIN\n");
> >
> > For easy parsing it is better to only report the interesting data
> > and let a user space utility make fancy presentation.
> Is that your way of saying take the above line out?

yes, (also wanted to explain why)

> > > +ÂÂÂ bufpos += n;
> > > +ÂÂÂ nchars += n;
> > > +
> > > +ÂÂÂ n = sprintf(bufpos, "--------------\n");
> > > +ÂÂÂ bufpos += n;
> > > +ÂÂÂ nchars += n;
> > > +
> > > +ÂÂÂ for_each_set_bit_inv(apid, matrix_mdev->matrix->apm,
> > > +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ matrix_mdev->matrix->apm_max) {
> > > +ÂÂÂÂÂÂÂ n = sprintf(bufpos, "%02lx\n", apid);
> > > +ÂÂÂÂÂÂÂ bufpos += n;
> > > +ÂÂÂÂÂÂÂ nchars += n;
> > > +
> > > +ÂÂÂÂÂÂÂ for_each_set_bit_inv(apqi, matrix_mdev->matrix->aqm,
> > > +ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ matrix_mdev->matrix->aqm_max) {
> > > +ÂÂÂÂÂÂÂÂÂÂÂ n = sprintf(bufpos, "%02lx.%04lx\n", apid, apqi);
> > > +ÂÂÂÂÂÂÂÂÂÂÂ bufpos += n;
> > > +ÂÂÂÂÂÂÂÂÂÂÂ nchars += n;
> > > +ÂÂÂÂÂÂÂ }
> > > +ÂÂÂ }
> > > +
> > > +ÂÂÂ return nchars;
> > > +}
> > > +DEVICE_ATTR_RO(matrix);
> > > +
> > > +
> > > Â static struct attribute *vfio_ap_mdev_attrs[] = {
> > > ÂÂÂÂÂ &dev_attr_assign_adapter.attr,
> > > ÂÂÂÂÂ &dev_attr_unassign_adapter.attr,
> > > @@ -700,6 +738,7 @@ static ssize_t control_domains_show(struct 
> > > device *dev,
> > > ÂÂÂÂÂ &dev_attr_assign_control_domain.attr,
> > > ÂÂÂÂÂ &dev_attr_unassign_control_domain.attr,
> > > ÂÂÂÂÂ &dev_attr_control_domains.attr,
> > > +ÂÂÂ &dev_attr_matrix.attr,
> > > ÂÂÂÂÂ NULL,
> > > Â };

--
Pierre Morel
Linux/KVM/QEMU in BÃblingen - Germany