Messages in this thread | | | Subject | Re: [PATCH v2 5/7] s390: vfio-ap: allow hot plug/unplug of AP resources using mdev device | From | Pierre Morel <> | Date | Mon, 6 May 2019 12:42:51 +0200 |
| |
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 <akrowiak@linux.ibm.com> > --- > 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
> 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.
> + > + 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.
-- Pierre Morel Linux/KVM/QEMU in Böblingen - Germany
| |