Re: [PATCH v9 11/22] s390: vfio-ap: sysfs interfaces to configure domains

[Tony Krowiak]

On 08/15/2018 08:05 AM, Cornelia Huck wrote:
> On Mon, 13 Aug 2018 17:48:08 -0400
> Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx> wrote:
>
> > From: Tony Krowiak <akrowiak@xxxxxxxxxxxxx>
> >
> > Introduces two new sysfs attributes for the VFIO mediated
> > matrix device for assigning AP domains to and unassigning
> > AP domains from a mediated matrix device. The IDs of the
> > AP domains assigned to the mediated matrix device will be
> > stored in an AP queue mask (AQM).
> >
> > The bits in the AQM, from most significant to least
> > significant bit, correspond to AP queue index (APQI) 0 to
> > 255 (note that an APQI is synonymous with with a domain ID).
> > On some systems, the maximum allowable domain number may be
> > less than 255 - depending upon the host's AP configuration -
> > and assignment may be rejected if the input domain ID exceeds
> > the limit.
> >
> > When a domain is assigned, the bit corresponding to the APQI
> > will be set in the AQM. Likewise, when a domain is unassigned,
> > the bit corresponding to the APQI will be cleared from the AQM.
> >
> > In order to successfully assign a domain, the APQNs derived from
> > the domain ID being assigned and the adapter numbers of all
> > adapters previously assigned:
> >
> > 1. Must be bound to the vfio_ap device driver.
> >
> > 2. Must not be assigned to any other mediated matrix device.
> >
> > If there are no adapters assigned to the mdev, then there must
> > be an AP queue bound to the vfio_ap device driver with an
> > APQN containing the domain ID (i.e., APQI), otherwise all
> > adapters subsequently assigned will fail because there will be no
> > AP queues bound with an APQN containing the APQI.
> >
> > Assigning or un-assigning an AP domain will also be rejected if
> > a guest using the mediated matrix device is running.
> >
> > The relevant sysfs structures are:
> >
> > /sys/devices/vfio_ap/matrix/
> > ...... [mdev_supported_types]
> > ......... [vfio_ap-passthrough]
> > ............ [devices]
> > ...............[$uuid]
> > .................. assign_domain
> > .................. unassign_domain
> >
> > To assign a domain to the $uuid mediated matrix device,
> > write the domain's ID to the assign_domain file. To
> > unassign a domain, write the domain's ID to the
> > unassign_domain file. The ID is specified using
> > conventional semantics: If it begins with 0x, the number
> > will be parsed as a hexadecimal (case insensitive) number;
> > if it begins with 0, it will be parsed as an octal number;
> > otherwise, it will be parsed as a decimal number.
> >
> > For example, to assign domain 173 (0xad) to the mediated matrix
> > device $uuid:
> >
> > 	echo 173 > assign_domain
> >
> > 	or
> >
> > 	echo 0255 > assign_domain
> >
> > 	or
> >
> > 	echo 0xad > assign_domain
> >
> > To unassign domain 173 (0xad):
> >
> > 	echo 173 > unassign_domain
> >
> > 	or
> >
> > 	echo 0255 > unassign_domain
> >
> > 	or
> >
> > 	echo 0xad > unassign_domain
> >
> > Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx>
> > Reviewed-by: Halil Pasic <pasic@xxxxxxxxxxxxx>
> > Tested-by: Michael Mueller <mimu@xxxxxxxxxxxxx>
> > Tested-by: Farhan Ali <alifm@xxxxxxxxxxxxx>
> > Tested-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> > Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
> > ---
> >   drivers/s390/crypto/vfio_ap_ops.c |   88 ++++++++++++++++++++++++++++++++++++-
> >   1 files changed, 87 insertions(+), 1 deletions(-)
> Looks sane to me.

Sanity rules!

>