On Fri, 21 Aug 2020 15:56:03 -0400 Tony Krowiak <[email protected]> wrote:
> Let's create links between each queue device bound to the vfio_ap device How about: Let us establish a bidirectional link... we kind of had a shaky queue --> matrix_mdev link prior to this patch, you are making this one solid and you are adding the matrix_mdev --> queue link. > driver and the matrix mdev to which the queue is assigned. The idea is to > facilitate efficient retrieval of the objects representing the queue > devices and matrix mdevs as well as to verify that a queue assigned to > a matrix mdev is bound to the driver. > I will have to look at the rest of the series to figure the usage out. One thought in the back of my head is that if vfio_ap_get_queue(apqn) is already O(1) the there is not much efficiency to gain by adding another hashtable whose keys are apqns and values queues. But I don't want to hang up myself on this. > The links will be created as follows: > > * When the queue device is probed, if its APQN is assigned to a matrix > mdev, the structures representing the queue device and the matrix mdev > will be linked. > > * When an adapter or domain is assigned to a matrix mdev, for each new > APQN assigned that references a queue device bound to the vfio_ap > device driver, the structures representing the queue device and the > matrix mdev will be linked. > > The links will be removed as follows: > > * When the queue device is removed, if its APQN is assigned to a matrix > mdev, the structures representing the queue device and the matrix mdev > will be unlinked. > > * When an adapter or domain is unassigned from a matrix mdev, for each > APQN unassigned that references a queue device bound to the vfio_ap > device driver, the structures representing the queue device and the > matrix mdev will be unlinked. > > Signed-off-by: Tony Krowiak <[email protected]> Except for the things pointed out by Connie and Christian, LGTM. > --- > drivers/s390/crypto/vfio_ap_ops.c | 132 +++++++++++++++++++++++++- > drivers/s390/crypto/vfio_ap_private.h | 2 + > 2 files changed, 129 insertions(+), 5 deletions(-) > > diff --git a/drivers/s390/crypto/vfio_ap_ops.c > b/drivers/s390/crypto/vfio_ap_ops.c > index ad3925f04f61..2e37ee82e422 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -50,6 +50,19 @@ static struct vfio_ap_queue *vfio_ap_get_queue(unsigned > long apqn) > return q; > } > > +static struct vfio_ap_queue *vfio_ap_get_mdev_queue(struct ap_matrix_mdev > *matrix_mdev, > + unsigned long apqn) > +{ > + struct vfio_ap_queue *q; > + > + hash_for_each_possible(matrix_mdev->qtable, q, mdev_qnode, apqn) { > + if (q && (q->apqn == apqn)) > + return q; > + } > + > + return NULL; > +} > + > /** > * vfio_ap_wait_for_irqclear > * @apqn: The AP Queue number > @@ -160,7 +173,6 @@ static struct ap_queue_status vfio_ap_irq_disable(struct > vfio_ap_queue *q) > status.response_code); > end_free: > vfio_ap_free_aqic_resources(q); > - q->matrix_mdev = NULL; > return status; > } > > @@ -262,7 +274,6 @@ static int handle_pqap(struct kvm_vcpu *vcpu) > struct vfio_ap_queue *q; > struct ap_queue_status qstatus = { > .response_code = AP_RESPONSE_Q_NOT_AVAIL, }; > - struct ap_matrix_mdev *matrix_mdev; > > /* If we do not use the AIV facility just go to userland */ > if (!(vcpu->arch.sie_block->eca & ECA_AIV)) > @@ -273,14 +284,11 @@ static int handle_pqap(struct kvm_vcpu *vcpu) > > if (!vcpu->kvm->arch.crypto.pqap_hook) > goto out_unlock; > - matrix_mdev = container_of(vcpu->kvm->arch.crypto.pqap_hook, > - struct ap_matrix_mdev, pqap_hook); > > q = vfio_ap_get_queue(apqn); > if (!q) > goto out_unlock; > > - q->matrix_mdev = matrix_mdev; > status = vcpu->run->s.regs.gprs[1]; > > /* If IR bit(16) is set we enable the interrupt */ > @@ -320,6 +328,7 @@ static int vfio_ap_mdev_create(struct kobject *kobj, > struct mdev_device *mdev) > > matrix_mdev->mdev = mdev; > vfio_ap_matrix_init(&matrix_dev->info, &matrix_mdev->matrix); > + hash_init(matrix_mdev->qtable); > mdev_set_drvdata(mdev, matrix_mdev); > matrix_mdev->pqap_hook.hook = handle_pqap; > matrix_mdev->pqap_hook.owner = THIS_MODULE; > @@ -548,6 +557,87 @@ static int vfio_ap_mdev_verify_no_sharing(struct > ap_matrix_mdev *matrix_mdev) > return 0; > } > > +enum qlink_type { > + LINK_APID, > + LINK_APQI, > + UNLINK_APID, > + UNLINK_APQI, > +}; > + > +static void vfio_ap_mdev_link_queue(struct ap_matrix_mdev *matrix_mdev, > + unsigned long apid, unsigned long apqi) > +{ > + struct vfio_ap_queue *q; > + > + q = vfio_ap_get_queue(AP_MKQID(apid, apqi)); > + if (q) { > + q->matrix_mdev = matrix_mdev; > + hash_add(matrix_mdev->qtable, > + &q->mdev_qnode, q->apqn); > + } > +} > + > +static void vfio_ap_mdev_unlink_queue(unsigned long apid, unsigned long apqi) > +{ > + struct vfio_ap_queue *q; > + > + q = vfio_ap_get_queue(AP_MKQID(apid, apqi)); > + if (q) { > + q->matrix_mdev = NULL; > + hash_del(&q->mdev_qnode); > + } > +} > + > +/** > + * vfio_ap_mdev_link_queues > + * > + * @matrix_mdev: The matrix mdev to link. > + * @type: The type of @qlink_id. > + * @qlink_id: The APID or APQI of the queues to link. > + * > + * Sets or clears the links between the queues with the specified @qlink_id > + * and the @matrix_mdev: > + * @type == LINK_APID: Set the links between the @matrix_mdev and the > + * queues with the specified @qlink_id (APID) > + * @type == LINK_APQI: Set the links between the @matrix_mdev and the > + * queues with the specified @qlink_id (APQI) > + * @type == UNLINK_APID: Clear the links between the @matrix_mdev and the > + * queues with the specified @qlink_id (APID) > + * @type == UNLINK_APQI: Clear the links between the @matrix_mdev and the > + * queues with the specified @qlink_id (APQI) > + */ > +static void vfio_ap_mdev_link_queues(struct ap_matrix_mdev *matrix_mdev, > + enum qlink_type type, > + unsigned long qlink_id) > +{ > + unsigned long id; > + > + switch (type) { > + case LINK_APID: > + for_each_set_bit_inv(id, matrix_mdev->matrix.aqm, > + matrix_mdev->matrix.aqm_max + 1) > + vfio_ap_mdev_link_queue(matrix_mdev, qlink_id, id); > + break; > + case UNLINK_APID: > + for_each_set_bit_inv(id, matrix_mdev->matrix.aqm, > + matrix_mdev->matrix.aqm_max + 1) > + vfio_ap_mdev_unlink_queue(qlink_id, id); > + break; > + case LINK_APQI: > + for_each_set_bit_inv(id, matrix_mdev->matrix.apm, > + matrix_mdev->matrix.apm_max + 1) > + vfio_ap_mdev_link_queue(matrix_mdev, id, qlink_id); > + break; > + case UNLINK_APQI: > + for_each_set_bit_inv(id, matrix_mdev->matrix.apm, > + matrix_mdev->matrix.apm_max + 1) > + vfio_ap_mdev_link_queue(matrix_mdev, id, qlink_id); > + break; > + default: > + WARN_ON_ONCE(1); > + } > +} > + > /** > * assign_adapter_store > * > @@ -617,6 +707,7 @@ static ssize_t assign_adapter_store(struct device *dev, > if (ret) > goto share_err; > > + vfio_ap_mdev_link_queues(matrix_mdev, LINK_APID, apid); > ret = count; > goto done; > > @@ -668,6 +759,7 @@ static ssize_t unassign_adapter_store(struct device *dev, > > mutex_lock(&matrix_dev->lock); > clear_bit_inv((unsigned long)apid, matrix_mdev->matrix.apm); > + vfio_ap_mdev_link_queues(matrix_mdev, UNLINK_APID, apid); > mutex_unlock(&matrix_dev->lock); > > return count; > @@ -758,6 +850,7 @@ static ssize_t assign_domain_store(struct device *dev, > if (ret) > goto share_err; > > + vfio_ap_mdev_link_queues(matrix_mdev, LINK_APQI, apqi); > ret = count; > goto done; > > @@ -810,6 +903,7 @@ static ssize_t unassign_domain_store(struct device *dev, > > mutex_lock(&matrix_dev->lock); > clear_bit_inv((unsigned long)apqi, matrix_mdev->matrix.aqm); > + vfio_ap_mdev_link_queues(matrix_mdev, UNLINK_APQI, apqi); > mutex_unlock(&matrix_dev->lock); > > return count; > @@ -1282,6 +1376,29 @@ void vfio_ap_mdev_unregister(void) > mdev_unregister_device(&matrix_dev->device); > } > > +/** > + * vfio_ap_queue_link_mdev > + * > + * @q: The queue to link with the matrix mdev. > + * > + * Links @q with the matrix mdev to which the queue's APQN is assigned. > + */ > +static void vfio_ap_queue_link_mdev(struct vfio_ap_queue *q) > +{ > + unsigned long apid = AP_QID_CARD(q->apqn); > + unsigned long apqi = AP_QID_QUEUE(q->apqn); > + struct ap_matrix_mdev *matrix_mdev; > + > + list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) { > + if (test_bit_inv(apid, matrix_mdev->matrix.apm) && > + test_bit_inv(apqi, matrix_mdev->matrix.aqm)) { > + q->matrix_mdev = matrix_mdev; > + hash_add(matrix_mdev->qtable, &q->mdev_qnode, q->apqn); > + break; > + } > + } > +} > + > int vfio_ap_mdev_probe_queue(struct ap_queue *queue) > { > struct vfio_ap_queue *q; > @@ -1290,9 +1407,12 @@ int vfio_ap_mdev_probe_queue(struct ap_queue *queue) > if (!q) > return -ENOMEM; > > + mutex_lock(&matrix_dev->lock); > dev_set_drvdata(&queue->ap_dev.device, q); > q->apqn = queue->qid; > q->saved_isc = VFIO_AP_ISC_INVALID; > + vfio_ap_queue_link_mdev(q); > + mutex_unlock(&matrix_dev->lock); > > return 0; > } > @@ -1309,6 +1429,8 @@ void vfio_ap_mdev_remove_queue(struct ap_queue *queue) > apqi = AP_QID_QUEUE(q->apqn); > vfio_ap_mdev_reset_queue(apid, apqi, 1); > vfio_ap_irq_disable(q); > + if (q->matrix_mdev) > + hash_del(&q->mdev_qnode); > kfree(q); > mutex_unlock(&matrix_dev->lock); > } > diff --git a/drivers/s390/crypto/vfio_ap_private.h > b/drivers/s390/crypto/vfio_ap_private.h > index a2aa05bec718..57da703b549a 100644 > --- a/drivers/s390/crypto/vfio_ap_private.h > +++ b/drivers/s390/crypto/vfio_ap_private.h > @@ -87,6 +87,7 @@ struct ap_matrix_mdev { > struct kvm *kvm; > struct kvm_s390_module_hook pqap_hook; > struct mdev_device *mdev; > + DECLARE_HASHTABLE(qtable, 8); > }; > > extern int vfio_ap_mdev_register(void); > @@ -98,6 +99,7 @@ struct vfio_ap_queue { > int apqn; > #define VFIO_AP_ISC_INVALID 0xff > unsigned char saved_isc; > + struct hlist_node mdev_qnode; > }; > > int vfio_ap_mdev_probe_queue(struct ap_queue *queue);
