From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [PATCH v2 5/7] s390: vfio-ap: allow hot plug/unplug of AP resources using mdev device References: <1556918073-13171-1-git-send-email-akrowiak@linux.ibm.com> <1556918073-13171-6-git-send-email-akrowiak@linux.ibm.com> From: Tony Krowiak Date: Mon, 6 May 2019 16:39:01 -0400 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8"; format="flowed" Content-Language: en-US Content-Transfer-Encoding: 8bit Message-Id: <8106bb9d-c881-adcf-cfbb-316e6c2281ba@linux.ibm.com> Sender: kvm-owner@vger.kernel.org List-Archive: List-Post: To: pmorel@linux.ibm.com, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: freude@linux.ibm.com, borntraeger@de.ibm.com, cohuck@redhat.com, frankja@linux.ibm.com, david@redhat.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, pasic@linux.ibm.com, alex.williamson@redhat.com, kwankhede@nvidia.com List-ID: On 5/6/19 6:42 AM, Pierre Morel wrote: > On 03/05/2019 23:14, Tony Krowiak wrote: >> Let's allow AP resources to be assigned to or unassigned from an AP >> matrix >> mdev device while it is in use by a guest. If a guest is using the mdev >> device while assignment is taking place, the guest will be granted access >> to the resource as long as the guest will not be given access to an AP >> queue device that is not bound to the vfio_ap device driver. If a >> guest is >> using the mdev device while unassignment is taking place, access to the >> resource will be taken from the guest. >> >> Signed-off-by: Tony Krowiak >> --- >>   drivers/s390/crypto/vfio_ap_ops.c | 116 >> ++++++++++++++++++++++++++++---------- >>   1 file changed, 86 insertions(+), 30 deletions(-) >> >> diff --git a/drivers/s390/crypto/vfio_ap_ops.c >> b/drivers/s390/crypto/vfio_ap_ops.c >> index ea24caf17a16..ede45184eb67 100644 >> --- a/drivers/s390/crypto/vfio_ap_ops.c >> +++ b/drivers/s390/crypto/vfio_ap_ops.c >> @@ -226,6 +226,8 @@ static struct device >> *vfio_ap_get_queue_dev(unsigned long apid, >>                     &apqn, match_apqn); >>   } >> + >> + > > two white lines I will fix it. > >>   static int vfio_ap_mdev_validate_masks(unsigned long *apm, unsigned >> long *aqm) >>   { >>       int ret; >> @@ -237,6 +239,26 @@ static int vfio_ap_mdev_validate_masks(unsigned >> long *apm, unsigned long *aqm) >>       return vfio_ap_mdev_verify_no_sharing(apm, aqm); >>   } >> +static bool vfio_ap_queues_on_drv(unsigned long *apm, unsigned long >> *aqm) >> +{ >> +    unsigned long apid, apqi, apqn; >> +    struct device *dev; >> + >> +    for_each_set_bit_inv(apid, apm, AP_DEVICES) { >> +        for_each_set_bit_inv(apqi, aqm, AP_DOMAINS) { >> +            apqn = AP_MKQID(apid, apqi); > > You do not use apqn in the function. Must be a remnant of another iteration. I'll remove it. > >> + >> +            dev = vfio_ap_get_queue_dev(apid, apqi); >> +            if (!dev) >> +                return false; >> + >> +            put_device(dev); >> +        } >> +    } >> + >> +    return true; >> +} >> + >>   /** >>    * assign_adapter_store >>    * >> @@ -247,7 +269,10 @@ static int vfio_ap_mdev_validate_masks(unsigned >> long *apm, unsigned long *aqm) >>    * @count:    the number of bytes in @buf >>    * >>    * Parses the APID from @buf and sets the corresponding bit in the >> mediated >> - * matrix device's APM. >> + * matrix device's APM. If a guest is using the mediated matrix >> device and each >> + * new APQN formed as a result of the assignment identifies an AP >> queue device >> + * that is bound to the vfio_ap device driver, the guest will be >> granted access >> + * to the adapter with the specified APID. >>    * >>    * Returns the number of bytes processed if the APID is valid; >> otherwise, >>    * returns one of the following errors: >> @@ -279,10 +304,6 @@ static ssize_t assign_adapter_store(struct device >> *dev, >>       struct mdev_device *mdev = mdev_from_dev(dev); >>       struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); >> -    /* If the guest is running, disallow assignment of adapter */ >> -    if (matrix_mdev->kvm) >> -        return -EBUSY; >> - >>       ret = kstrtoul(buf, 0, &apid); >>       if (ret) >>           return ret; >> @@ -300,6 +321,14 @@ static ssize_t assign_adapter_store(struct device >> *dev, >>           return ret; >>       } >>       set_bit_inv(apid, matrix_mdev->matrix.apm); >> + >> +    if (matrix_mdev->shadow_crycb) { >> +        if (vfio_ap_queues_on_drv(apm, >> +                      matrix_mdev->shadow_crycb->aqm)) { >> +            set_bit_inv(apid, matrix_mdev->shadow_crycb->apm); >> +            vfio_ap_mdev_update_crycb(matrix_mdev); >> +        } >> +    } >>       mutex_unlock(&matrix_dev->lock); >>       return count; >> @@ -315,7 +344,9 @@ static DEVICE_ATTR_WO(assign_adapter); >>    * @count:    the number of bytes in @buf >>    * >>    * Parses the APID from @buf and clears the corresponding bit in the >> mediated >> - * matrix device's APM. >> + * matrix device's APM. If a guest is using the mediated matrix >> device and has >> + * access to the AP adapter with the specified APID, access to the >> adapter will >> + * be taken from the guest. >>    * >>    * Returns the number of bytes processed if the APID is valid; >> otherwise, >>    * returns one of the following errors: >> @@ -332,10 +363,6 @@ static ssize_t unassign_adapter_store(struct >> device *dev, >>       struct mdev_device *mdev = mdev_from_dev(dev); >>       struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); >> -    /* If the guest is running, disallow un-assignment of adapter */ >> -    if (matrix_mdev->kvm) >> -        return -EBUSY; >> - >>       ret = kstrtoul(buf, 0, &apid); >>       if (ret) >>           return ret; >> @@ -345,6 +372,13 @@ static ssize_t unassign_adapter_store(struct >> device *dev, >>       mutex_lock(&matrix_dev->lock); >>       clear_bit_inv((unsigned long)apid, matrix_mdev->matrix.apm); >> + >> +    if (matrix_mdev->shadow_crycb) { >> +        if (test_bit_inv(apid, matrix_mdev->shadow_crycb->apm)) { >> +            clear_bit_inv(apid, matrix_mdev->shadow_crycb->apm); >> +            vfio_ap_mdev_update_crycb(matrix_mdev); >> +        } >> +    } >>       mutex_unlock(&matrix_dev->lock); >>       return count; >> @@ -361,7 +395,10 @@ static DEVICE_ATTR_WO(unassign_adapter); >>    * @count:    the number of bytes in @buf >>    * >>    * Parses the APQI from @buf and sets the corresponding bit in the >> mediated >> - * matrix device's AQM. >> + * matrix device's AQM. If a guest is using the mediated matrix >> device and each >> + * new APQN formed as a result of the assignment identifies an AP >> queue device >> + * that is bound to the vfio_ap device driver, the guest will be >> given access >> + * to the AP queue(s) with the specified APQI. >>    * >>    * Returns the number of bytes processed if the APQI is valid; >> otherwise returns >>    * one of the following errors: >> @@ -394,10 +431,6 @@ static ssize_t assign_domain_store(struct device >> *dev, >>       struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); >>       unsigned long max_apqi = matrix_mdev->matrix.aqm_max; >> -    /* If the guest is running, disallow assignment of domain */ >> -    if (matrix_mdev->kvm) >> -        return -EBUSY; >> - >>       ret = kstrtoul(buf, 0, &apqi); >>       if (ret) >>           return ret; >> @@ -414,6 +447,14 @@ static ssize_t assign_domain_store(struct device >> *dev, >>           return ret; >>       } >>       set_bit_inv(apqi, matrix_mdev->matrix.aqm); >> + >> +    if (matrix_mdev->shadow_crycb) { >> +        if (vfio_ap_queues_on_drv(matrix_mdev->shadow_crycb->apm, >> +                      aqm)) { >> +            set_bit_inv(apqi, matrix_mdev->shadow_crycb->aqm); >> +            vfio_ap_mdev_update_crycb(matrix_mdev); >> +        } >> +    } >>       mutex_unlock(&matrix_dev->lock); >>       return count; >> @@ -431,7 +472,9 @@ static DEVICE_ATTR_WO(assign_domain); >>    * @count:    the number of bytes in @buf >>    * >>    * Parses the APQI from @buf and clears the corresponding bit in the >> - * mediated matrix device's AQM. >> + * mediated matrix device's AQM. If a guest is using the mediated >> matrix device >> + * and has access to queue(s) with the specified domain APQI, access to >> + * the queue(s) will be taken away from the guest. >>    * >>    * Returns the number of bytes processed if the APQI is valid; >> otherwise, >>    * returns one of the following errors: >> @@ -447,10 +490,6 @@ static ssize_t unassign_domain_store(struct >> device *dev, >>       struct mdev_device *mdev = mdev_from_dev(dev); >>       struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); >> -    /* If the guest is running, disallow un-assignment of domain */ >> -    if (matrix_mdev->kvm) >> -        return -EBUSY; >> - >>       ret = kstrtoul(buf, 0, &apqi); >>       if (ret) >>           return ret; >> @@ -460,6 +499,13 @@ static ssize_t unassign_domain_store(struct >> device *dev, >>       mutex_lock(&matrix_dev->lock); >>       clear_bit_inv((unsigned long)apqi, matrix_mdev->matrix.aqm); >> + >> +    if (matrix_mdev->shadow_crycb) { >> +        if (test_bit_inv(apqi, matrix_mdev->shadow_crycb->aqm)) { >> +            clear_bit_inv(apqi, matrix_mdev->shadow_crycb->aqm); >> +            vfio_ap_mdev_update_crycb(matrix_mdev); >> +        } >> +    } >>       mutex_unlock(&matrix_dev->lock); >>       return count; >> @@ -475,7 +521,9 @@ static DEVICE_ATTR_WO(unassign_domain); >>    * @count:    the number of bytes in @buf >>    * >>    * Parses the domain ID from @buf and sets the corresponding bit in >> the mediated >> - * matrix device's ADM. >> + * matrix device's ADM. If a guest is using the mediated matrix >> device and the >> + * guest does not have access to the control domain with the >> specified ID, the >> + * guest will be granted access to it. >>    * >>    * Returns the number of bytes processed if the domain ID is valid; >> otherwise, >>    * returns one of the following errors: >> @@ -491,10 +539,6 @@ static ssize_t assign_control_domain_store(struct >> device *dev, >>       struct mdev_device *mdev = mdev_from_dev(dev); >>       struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); >> -    /* If the guest is running, disallow assignment of control domain */ >> -    if (matrix_mdev->kvm) >> -        return -EBUSY; >> - >>       ret = kstrtoul(buf, 0, &id); >>       if (ret) >>           return ret; >> @@ -504,6 +548,13 @@ static ssize_t assign_control_domain_store(struct >> device *dev, >>       mutex_lock(&matrix_dev->lock); >>       set_bit_inv(id, matrix_mdev->matrix.adm); >> + >> +    if (matrix_mdev->shadow_crycb) { >> +        if (!test_bit_inv(id, matrix_mdev->shadow_crycb->adm)) { >> +            set_bit_inv(id, matrix_mdev->shadow_crycb->adm); >> +            vfio_ap_mdev_update_crycb(matrix_mdev); >> +        } >> +    } >>       mutex_unlock(&matrix_dev->lock); >>       return count; >> @@ -519,7 +570,9 @@ static DEVICE_ATTR_WO(assign_control_domain); >>    * @count:    the number of bytes in @buf >>    * >>    * Parses the domain ID from @buf and clears the corresponding bit >> in the >> - * mediated matrix device's ADM. >> + * mediated matrix device's ADM. If a guest is using the mediated >> matrix device >> + * and has access to control domain with the specified domain ID, >> access to >> + * the control domain will be taken from the guest. >>    * >>    * Returns the number of bytes processed if the domain ID is valid; >> otherwise, >>    * returns one of the following errors: >> @@ -536,10 +589,6 @@ static ssize_t >> unassign_control_domain_store(struct device *dev, >>       struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); >>       unsigned long max_domid =  matrix_mdev->matrix.adm_max; >> -    /* If the guest is running, disallow un-assignment of control >> domain */ >> -    if (matrix_mdev->kvm) >> -        return -EBUSY; >> - >>       ret = kstrtoul(buf, 0, &domid); >>       if (ret) >>           return ret; >> @@ -548,6 +597,13 @@ static ssize_t >> unassign_control_domain_store(struct device *dev, >>       mutex_lock(&matrix_dev->lock); >>       clear_bit_inv(domid, matrix_mdev->matrix.adm); >> + >> +    if (matrix_mdev->shadow_crycb) { >> +        if (test_bit_inv(domid, matrix_mdev->shadow_crycb->adm)) { >> +            clear_bit_inv(domid, matrix_mdev->shadow_crycb->adm); >> +            vfio_ap_mdev_update_crycb(matrix_mdev); >> +        } >> +    } >>       mutex_unlock(&matrix_dev->lock); >>       return count; >> > > beside the two NITs, look good to me. > Still need to test. > > >