On 07/26/2018 09:54 PM, Christian Borntraeger wrote: [...] > +static void kvm_ap_merge_bitmasks(unsigned long *dst, unsigned long *mask1, > + unsigned long *mask2, unsigned long nbits) > +{ > + int i; > + > + for (i = 0; i < BITS_TO_LONGS(nbits); i++) > + dst[i] = mask1[i] | mask2[i]; > +} Could you use the standard bitmap_or() function instead of implementing your own version? > +static void vfio_ap_mdev_copy_masks(struct ap_matrix_mdev *matrix_mdev, > + struct kvm_s390_crypto_cb *crycb) > +{ > + int nbytes; > + unsigned long *apm, *aqm, *adm; > + > + switch (matrix_mdev->kvm->arch.crypto.crycbd & CRYCB_FORMAT_MASK) { > + case CRYCB_FORMAT2: > + apm = (unsigned long *)crycb->apcb1.apm; > + aqm = (unsigned long *)crycb->apcb1.aqm; > + adm = (unsigned long *)crycb->apcb1.adm; > + break; > + case CRYCB_FORMAT1: > + case CRYCB_FORMAT0: > + default: > + apm = (unsigned long *)crycb->apcb0.apm; > + aqm = (unsigned long *)crycb->apcb0.aqm; > + adm = (unsigned long *)crycb->apcb0.adm; > + break; > + } > + > + nbytes = DIV_ROUND_UP(matrix_mdev->matrix.apm_max + 1, BITS_PER_BYTE); > + memcpy(apm, matrix_mdev->matrix.apm, nbytes); > + nbytes = DIV_ROUND_UP(matrix_mdev->matrix.aqm_max + 1, BITS_PER_BYTE); > + memcpy(aqm, matrix_mdev->matrix.aqm, nbytes); > + kvm_ap_merge_bitmasks(adm, aqm, adm, matrix_mdev->matrix.adm_max + 1); > +} > + > +static int vfio_ap_mdev_group_notifier(struct notifier_block *nb, > + unsigned long action, void *data) > +{ > + int ret; > + struct ap_matrix_mdev *matrix_mdev; > + struct kvm_s390_crypto_cb *crycb; > + > + if (action == VFIO_GROUP_NOTIFY_SET_KVM) { > + matrix_mdev = container_of(nb, struct ap_matrix_mdev, > + group_notifier); > + matrix_mdev->kvm = data; > + crycb = matrix_mdev->kvm->arch.crypto.crycb; > + > + ret = kvm_ap_validate_crypto_setup(matrix_mdev->kvm); > + if (ret) > + return ret; > + > + /* NOTE: Happens before any vcpu is running (no hotplug). */ > + vfio_ap_mdev_copy_masks(matrix_mdev, crycb); > + if (ret) > + return ret; > + } > + > + return NOTIFY_OK; > +} > + > +/** > + * vfio_ap_mdev_open_once > + * > + * @matrix_mdev: a mediated matrix device > + * > + * Return 0 if no other mediated matrix device has been opened for the > + * KVM guest assigned to @matrix_mdev; otherwise, returns an error. > + */ > +static int vfio_ap_mdev_open_once(struct ap_matrix_mdev *matrix_mdev) > +{ > + int ret = 0; > + struct ap_matrix_mdev *lstdev; > + > + list_for_each_entry(lstdev, &matrix_dev.mdev_list, list) { > + if ((lstdev->kvm == matrix_mdev->kvm) && > + (lstdev != matrix_mdev)) { Too much parentheses again for my taste ;-) > + ret = -EPERM; > + break; > + } > + } Thomas