From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pierre Morel Subject: Re: [PATCH v6 11/21] s390: vfio-ap: sysfs interfaces to configure domains Date: Mon, 9 Jul 2018 14:13:52 +0200 Message-ID: <0b29176d-7222-6111-6fea-d8bde66fa670@linux.ibm.com> References: <1530306683-7270-1-git-send-email-akrowiak@linux.vnet.ibm.com> <1530306683-7270-12-git-send-email-akrowiak@linux.vnet.ibm.com> Reply-To: pmorel@linux.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format="flowed" Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <1530306683-7270-12-git-send-email-akrowiak@linux.vnet.ibm.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Archive: List-Post: To: Tony Krowiak , linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: freude@de.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, borntraeger@de.ibm.com, cohuck@redhat.com, kwankhede@nvidia.com, bjsdjshi@linux.vnet.ibm.com, pbonzini@redhat.com, alex.williamson@redhat.com, pmorel@linux.vnet.ibm.com, alifm@linux.vnet.ibm.com, mjrosato@linux.vnet.ibm.com, jjherne@linux.vnet.ibm.com, thuth@redhat.com, pasic@linux.vnet.ibm.com, berrange@redhat.com, fiuczy@linux.vnet.ibm.com, buendgen@de.ibm.com, Tony Krowiak List-ID: On 29/06/2018 23:11, Tony Krowiak 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; > 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 > > 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 > --- > drivers/s390/crypto/vfio_ap_ops.c | 173 ++++++++++++++++++++++++++++++++++++- > 1 files changed, 172 insertions(+), 1 deletions(-) > > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c > index a4351bd..a5b06e7 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -170,6 +170,27 @@ static int vfio_ap_queue_has_apid(struct device *dev, void *data) > } > > /** > + * vfio_ap_queue_has_apqi > + * > + * @dev: an AP queue device > + * @data: an AP queue index > + * > + * Flags whether any AP queue device has a particular AP queue index > + * > + * Returns 0 to indicate the function succeeded > + */ > +static int vfio_ap_queue_has_apqi(struct device *dev, void *data) > +{ > + struct vfio_id_reserved *id_res = data; > + struct ap_queue *ap_queue = to_ap_queue(dev); > + > + if (id_res->id == AP_QID_QUEUE(ap_queue->qid)) > + id_res->reserved = true; > + > + return 0; > +} > + > +/** > * vfio_ap_verify_qid_reserved > * > * @matrix_dev: a mediated matrix device > @@ -236,6 +257,42 @@ static int vfio_ap_verify_apid_reserved(struct ap_matrix_dev *matrix_dev, > return -EPERM; > } > > +/** > + * vfio_ap_verify_apqi_reserved > + * > + * @matrix_dev: a mediated matrix device > + * @apqi: an AP queue index > + * > + * Verifies that an AP queue with @apqi is reserved by the VFIO AP device > + * driver. > + * > + * Returns 0 if an AP queue with @apqi is reserved; otherwise, returns -ENODEV. > + */ > +static int vfio_ap_verify_apqi_reserved(struct ap_matrix_dev *matrix_dev, > + const char *mdev_name, > + unsigned long apqi) > +{ > + int ret; > + struct vfio_id_reserved id_res; > + > + id_res.id = apqi; > + id_res.reserved = false; > + > + ret = driver_for_each_device(matrix_dev->device.driver, NULL, &id_res, > + vfio_ap_queue_has_apqi); > + if (ret) > + return ret; > + > + if (id_res.reserved) > + return 0; > + > + pr_err("%s: mdev %s using queue %04lx not reserved by %s driver", > + VFIO_AP_MODULE_NAME, mdev_name, apqi, > + VFIO_AP_DRV_NAME); > + > + return -EPERM; > +} > + > static int vfio_ap_verify_queues_reserved(struct ap_matrix_dev *matrix_dev, > const char *mdev_name, > struct ap_matrix *matrix) > @@ -417,10 +474,124 @@ static ssize_t unassign_adapter_store(struct device *dev, > } > DEVICE_ATTR_WO(unassign_adapter); > > +/** > + * vfio_ap_validate_apqi > + * > + * @matrix_mdev: the mediated matrix device > + * @apqi: the APQI (domain ID) to validate > + * > + * Validates the value of @apqi: > + * * If there are no AP adapters assigned, then there must be at least > + * one AP queue device reserved by the VFIO AP device driver with an > + * APQN containing @apqi. Same as in preceding patch, I do not understand why you need this. Pierre -- Pierre Morel Linux/KVM/QEMU in Böblingen - Germany