Messages in this thread | | | Subject | Re: [PATCH v2 2/7] s390: vfio-ap: maintain a shadow of the guest's CRYCB | From | Pierre Morel <> | Date | Mon, 6 May 2019 08:49:29 +0200 |
| |
On 03/05/2019 23:14, Tony Krowiak wrote: > This patch introduces a shadow of the CRYCB being used by a guest. This > will enable to more effectively manage dynamic changes to the AP > resources installed on the host that may be assigned to an mdev device > and being used by a guest. For example: > > * AP adapter cards can be dynamically added to and removed from the AP > configuration via the SE or an SCLP command. > > * AP resources that disappear and reappear due to hardware malfunctions. > > * AP queues bound to and unbound from the vfio_ap device driver by a > root user. > > Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> > --- > drivers/s390/crypto/vfio_ap_ops.c | 91 ++++++++++++++++++++++++++++++++--- > drivers/s390/crypto/vfio_ap_private.h | 2 + > 2 files changed, 87 insertions(+), 6 deletions(-) > > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c > index b88a2a2ba075..44a04b4aa9ae 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -297,6 +297,45 @@ static void vfio_ap_mdev_wait_for_qempty(unsigned long apid, unsigned long apqi) > } while (--retry); > } > > +/* > + * vfio_ap_mdev_update_crycb > + * > + * @matrix_mdev: the mediated matrix device > + * > + * Updates the AP matrix in the guest's CRYCB from it's shadow masks. > + * > + * Returns zero if the guest's CRYCB is successfully updated; otherwise, > + * returns -ENODEV if a guest is not running or does not have a CRYCB. > + */ > +static int vfio_ap_mdev_update_crycb(struct ap_matrix_mdev *matrix_mdev) > +{ > + if (!matrix_mdev->kvm || !matrix_mdev->kvm->arch.crypto.crycbd) > + return -ENODEV; > + > + kvm_arch_crypto_set_masks(matrix_mdev->kvm, > + matrix_mdev->shadow_crycb->apm, > + matrix_mdev->shadow_crycb->aqm, > + matrix_mdev->shadow_crycb->adm); > + > + return 0; > +} > + > +static int match_apqn(struct device *dev, void *data) > +{ > + struct ap_queue *apq = to_ap_queue(dev); > + > + return (apq->qid == *(unsigned long *)(data)) ? 1 : 0; > +} > + > +static struct device *vfio_ap_get_queue_dev(unsigned long apid, > + unsigned long apqi) > +{ > + unsigned long apqn = AP_MKQID(apid, apqi); > + > + return driver_find_device(&matrix_dev->vfio_ap_drv->driver, NULL, > + &apqn, match_apqn); > +} > + > /** > * assign_adapter_store > * > @@ -805,14 +844,9 @@ static int vfio_ap_mdev_group_notifier(struct notifier_block *nb, > if (ret) > return NOTIFY_DONE; > > - /* If there is no CRYCB pointer, then we can't copy the masks */ > - if (!matrix_mdev->kvm->arch.crypto.crycbd) > + if (vfio_ap_mdev_update_crycb(matrix_mdev)) > return NOTIFY_DONE; > > - kvm_arch_crypto_set_masks(matrix_mdev->kvm, matrix_mdev->matrix.apm, > - matrix_mdev->matrix.aqm, > - matrix_mdev->matrix.adm); > - > return NOTIFY_OK; > } > > @@ -867,12 +901,55 @@ static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev) > return rc; > } > > +static int vfio_ap_mdev_create_shadow_crycb(struct ap_matrix_mdev *matrix_mdev) > +{ > + unsigned long apid, apqi, domid; > + struct device *dev; > + > + matrix_mdev->shadow_crycb = kzalloc(sizeof(*matrix_mdev->shadow_crycb), > + GFP_KERNEL); > + if (!matrix_mdev->shadow_crycb) > + return -ENOMEM; > + > + vfio_ap_matrix_init(&matrix_dev->info, matrix_mdev->shadow_crycb); > + > + /* > + * Examine each APQN assigned to the mdev device. Set the APID and APQI > + * in the shadow CRYCB if and only if the queue device identified by > + * the APQN is in the configuration. > + */ > + for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, > + matrix_mdev->matrix.apm_max + 1) { > + for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, > + matrix_mdev->matrix.aqm_max + 1) { > + dev = vfio_ap_get_queue_dev(apid, apqi); > + if (dev) { > + set_bit_inv(apid, > + matrix_mdev->shadow_crycb->apm); > + set_bit_inv(apqi, > + matrix_mdev->shadow_crycb->aqm); > + put_device(dev); > + }
I think that if we do not find a device here we have a problem. Don't we?
> + } > + } > + > + /* Set all control domains assigned to the mdev in the shadow CRYCB */ > + for_each_set_bit_inv(domid, matrix_mdev->matrix.adm, > + matrix_mdev->matrix.adm_max + 1) > + set_bit_inv(domid, matrix_mdev->shadow_crycb->adm); > + > + return 0; > +} > + > static int vfio_ap_mdev_open(struct mdev_device *mdev) > { > struct ap_matrix_mdev *matrix_mdev = mdev_get_drvdata(mdev); > unsigned long events; > int ret; > > + ret = vfio_ap_mdev_create_shadow_crycb(matrix_mdev); > + if (ret) > + return ret; > > if (!try_module_get(THIS_MODULE)) > return -ENODEV; > @@ -902,6 +979,8 @@ static void vfio_ap_mdev_release(struct mdev_device *mdev) > &matrix_mdev->group_notifier); > matrix_mdev->kvm = NULL; > module_put(THIS_MODULE); > + kfree(matrix_mdev->shadow_crycb); > + matrix_mdev->shadow_crycb = NULL; > } > > static int vfio_ap_mdev_get_device_info(unsigned long arg) > diff --git a/drivers/s390/crypto/vfio_ap_private.h b/drivers/s390/crypto/vfio_ap_private.h > index 76b7f98e47e9..e8457aa61976 100644 > --- a/drivers/s390/crypto/vfio_ap_private.h > +++ b/drivers/s390/crypto/vfio_ap_private.h > @@ -72,6 +72,7 @@ struct ap_matrix { > * @list: allows the ap_matrix_mdev struct to be added to a list > * @matrix: the adapters, usage domains and control domains assigned to the > * mediated matrix device. > + * @shadow_crycb: a shadow copy of the crycb in use by a guest > * @group_notifier: notifier block used for specifying callback function for > * handling the VFIO_GROUP_NOTIFY_SET_KVM event > * @kvm: the struct holding guest's state > @@ -79,6 +80,7 @@ struct ap_matrix { > struct ap_matrix_mdev { > struct list_head node; > struct ap_matrix matrix; > + struct ap_matrix *shadow_crycb; > struct notifier_block group_notifier; > struct kvm *kvm; > }; >
-- Pierre Morel Linux/KVM/QEMU in Böblingen - Germany
| |