On Wed, 14 Mar 2018 14:25:49 -0400 Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx> wrote: > Provides the sysfs interfaces for assigning AP domains to > and unassigning AP domains from a mediated matrix device. > > An AP domain ID corresponds to an AP queue index (APQI). For > each domain assigned to the mediated matrix device, its > corresponging APQI is stored in an AP queue mask (AQM). > The bits in the AQM, from most significant to least > significant bit, correspond to AP domain numbers 0 to 255. > When a domain is assigned, the bit corresponding to its > APQI will be set in the AQM. Likewise, when a domain is > unassigned, the bit corresponding to its APQI will be > cleared from the AQM. > > 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; > 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 0xad > assign_domain > > To unassign domain 173 (0xad): > > echo 173 > unassign_domain > > or > > echo 0xad > unassign_domain > > The assignment will be rejected: > > * If the domain ID exceeds the maximum value for an AP domain: > > * If the AP Extended Addressing (APXA) facility is installed, > the max value is 255 > > * Else the max value is 15 > > * If no AP adapters have yet been assigned and there are > no AP queues reserved by the VFIO AP driver that have an APQN > with an APQI matching that of the AP domain number being > assigned. > > * If any of the APQNs that can be derived from the intersection > of the APQI being assigned and the AP adapter ID (APID) of > each of the AP adapters previously assigned can not be matched > with an APQN of an AP queue device reserved by the VFIO AP > driver. > > Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx> > --- > arch/s390/include/asm/kvm-ap.h | 1 + > drivers/s390/crypto/vfio_ap_ops.c | 215 ++++++++++++++++++++++++++++++++++++- > 2 files changed, 215 insertions(+), 1 deletions(-) > > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c > index 90512a6..c448835 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -377,10 +377,223 @@ static ssize_t unassign_adapter_store(struct device *dev, > } > DEVICE_ATTR_WO(unassign_adapter); > > +/** > + * vfio_ap_validate_queues_for_apqi > + * > + * @ap_matrix: the matrix device > + * @matrix_mdev: the mediated matrix device > + * @apqi: an AP queue index (APQI) - corresponds to a domain ID > + * > + * Verifies that each APQN that is derived from the intersection of @apqi and > + * each AP adapter ID (APID) corresponding to an AP domain assigned to the > + * @matrix_mdev matches the APQN of an AP queue reserved by the VFIO AP device > + * driver. > + * > + * Returns 0 if validation succeeds; otherwise, returns an error. > + */ > +static int vfio_ap_validate_queues_for_apqi(struct ap_matrix *ap_matrix, > + struct ap_matrix_mdev *matrix_mdev, > + unsigned long apqi) > +{ > + int ret; > + struct vfio_ap_qid_match qid_match; > + unsigned long apid; > + struct device_driver *drv = ap_matrix->device.driver; > + > + /** > + * Examine each APQN with the specified APQI > + */ > + for_each_set_bit_inv(apid, matrix_mdev->matrix->apm, > + matrix_mdev->matrix->apm_max) { > + qid_match.qid = AP_MKQID(apid, apqi); > + qid_match.dev = NULL; > + > + ret = driver_for_each_device(drv, NULL, &qid_match, > + vfio_ap_queue_match); > + if (ret) > + return ret; Hm, I'm wondering whether jumping out of the outer loop is the correct thing to do here - and if yes, whether we should log an error? > + > + /* > + * If the APQN identifies an AP queue that is reserved by the > + * VFIO AP device driver, continue processing. > + */ > + if (qid_match.dev) > + continue; > + > + pr_err("%s: AP queue %02lx.%04lx not reserved by %s driver", > + VFIO_AP_MATRIX_MODULE_NAME, apqi, apqi, > + VFIO_AP_DRV_NAME); > + > + return -ENXIO; > + } > + > + return 0; > +} -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html