Re: [PATCH v3 11/14] s390: vfio-ap: sysfs interface to view matrix mdev matrix
From: Cornelia Huck
Date: Tue Mar 27 2018 - 07:19:25 EST
On Thu, 15 Mar 2018 10:42:33 +0100
Pierre Morel <pmorel@xxxxxxxxxxxxxxxxxx> 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:
> >
> > cat matrix
> >
> > Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx>
> > ---
> > drivers/s390/crypto/vfio_ap_ops.c | 39 +++++++++++++++++++++++++++++++++++++
> > 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,
> > }
> > DEVICE_ATTR_RO(control_domains);
> >
> > +static ssize_t matrix_show(struct device *dev, struct device_attribute *attr,
> > + char *buf)
> > +{
> > + struct mdev_device *mdev = mdev_from_dev(dev);
> > + struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev);
> > + char *bufpos = buf;
> > + unsigned long apid;
> > + unsigned long apqi;
> > + int nchars = 0;
> > + int n;
> > +
> > + 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.
+1. Attributes should normally be simple, one-value things.
>
> > + bufpos += n;
> > + nchars += n;
> > +
> > + n = sprintf(bufpos, "--------------\n");
> > + bufpos += n;
> > + nchars += n;
> > +
> > + for_each_set_bit_inv(apid, matrix_mdev->matrix->apm,
> > + matrix_mdev->matrix->apm_max) {
> > + n = sprintf(bufpos, "%02lx\n", apid);
> > + bufpos += n;
> > + nchars += n;
> > +
> > + for_each_set_bit_inv(apqi, matrix_mdev->matrix->aqm,
> > + matrix_mdev->matrix->aqm_max) {
> > + n = sprintf(bufpos, "%02lx.%04lx\n", apid, apqi);
> > + bufpos += n;
> > + nchars += n;
> > + }
> > + }
> > +
> > + return nchars;
> > +}
> > +DEVICE_ATTR_RO(matrix);
> > +
> > +
> > static struct attribute *vfio_ap_mdev_attrs[] = {
> > &dev_attr_assign_adapter.attr,
> > &dev_attr_unassign_adapter.attr,
> > @@ -700,6 +738,7 @@ static ssize_t control_domains_show(struct device *dev,
> > &dev_attr_assign_control_domain.attr,
> > &dev_attr_unassign_control_domain.attr,
> > &dev_attr_control_domains.attr,
> > + &dev_attr_matrix.attr,
> > NULL,
> > };
> >
>