On Fri, 21 Aug 2020 15:56:13 -0400 Tony Krowiak <[email protected]> wrote:
> Implements the driver callback invoked by the AP bus when the host > AP configuration has changed. Since this callback is invoked prior to > unbinding a device from its device driver, the vfio_ap driver will > respond by unplugging the AP adapters, domains and control domains > removed from the host's AP configuration from the guests using them. > > Signed-off-by: Tony Krowiak <[email protected]> > Reported-by: kernel test robot <[email protected]> Looks reasonable, but shouldn't vfio_ap_mdev_remove_queue() already have code that kicks the queue from the shadow at this stage? I mean if the removal is for a reason different that host config change, we wont update the guest_matrix or? > --- > drivers/s390/crypto/vfio_ap_drv.c | 5 +- > drivers/s390/crypto/vfio_ap_ops.c | 147 ++++++++++++++++++++++++-- > drivers/s390/crypto/vfio_ap_private.h | 7 +- > 3 files changed, 146 insertions(+), 13 deletions(-) > > diff --git a/drivers/s390/crypto/vfio_ap_drv.c > b/drivers/s390/crypto/vfio_ap_drv.c > index aae5b3d8e3fa..ea0a7603e886 100644 > --- a/drivers/s390/crypto/vfio_ap_drv.c > +++ b/drivers/s390/crypto/vfio_ap_drv.c > @@ -115,9 +115,11 @@ static int vfio_ap_matrix_dev_create(void) > > /* Fill in config info via PQAP(QCI), if available */ > if (test_facility(12)) { > - ret = ap_qci(&matrix_dev->info); > + ret = ap_qci(&matrix_dev->config_info); > if (ret) > goto matrix_alloc_err; > + memcpy(&matrix_dev->config_info_prev, &matrix_dev->config_info, > + sizeof(struct ap_config_info)); > } > > mutex_init(&matrix_dev->lock); > @@ -177,6 +179,7 @@ static int __init vfio_ap_init(void) > vfio_ap_drv.remove = vfio_ap_queue_dev_remove; > vfio_ap_drv.in_use = vfio_ap_mdev_resource_in_use; > vfio_ap_drv.ids = ap_queue_ids; > + vfio_ap_drv.on_config_changed = vfio_ap_on_cfg_changed; > > ret = ap_driver_register(&vfio_ap_drv, THIS_MODULE, VFIO_AP_DRV_NAME); > if (ret) { > diff --git a/drivers/s390/crypto/vfio_ap_ops.c > b/drivers/s390/crypto/vfio_ap_ops.c > index 2b01a8eb6ee7..e002d556abab 100644 > --- a/drivers/s390/crypto/vfio_ap_ops.c > +++ b/drivers/s390/crypto/vfio_ap_ops.c > @@ -347,7 +347,9 @@ 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); > + vfio_ap_matrix_init(&matrix_dev->config_info, &matrix_mdev->matrix); > + vfio_ap_matrix_init(&matrix_dev->config_info, > + &matrix_mdev->shadow_apcb); > hash_init(matrix_mdev->qtable); > mdev_set_drvdata(mdev, matrix_mdev); > matrix_mdev->pqap_hook.hook = handle_pqap; > @@ -526,8 +528,8 @@ static int vfio_ap_mdev_filter_matrix(struct > ap_matrix_mdev *matrix_mdev, > * If the APID is not assigned to the host AP configuration, > * we can not assign it to the guest's AP configuration > */ > - if (!test_bit_inv(apid, > - (unsigned long *)matrix_dev->info.apm)) { > + if (!test_bit_inv(apid, (unsigned long *) > + matrix_dev->config_info.apm)) { > clear_bit_inv(apid, shadow_apcb->apm); > continue; > } > @@ -540,7 +542,7 @@ static int vfio_ap_mdev_filter_matrix(struct > ap_matrix_mdev *matrix_mdev, > * guest's AP configuration > */ > if (!test_bit_inv(apqi, (unsigned long *) > - matrix_dev->info.aqm)) { > + matrix_dev->config_info.aqm)) { > clear_bit_inv(apqi, shadow_apcb->aqm); > continue; > } > @@ -594,7 +596,7 @@ static bool vfio_ap_mdev_config_shadow_apcb(struct > ap_matrix_mdev *matrix_mdev) > int napm, naqm; > struct ap_matrix shadow_apcb; > > - vfio_ap_matrix_init(&matrix_dev->info, &shadow_apcb); > + vfio_ap_matrix_init(&matrix_dev->config_info, &shadow_apcb); > napm = bitmap_weight(matrix_mdev->matrix.apm, AP_DEVICES); > naqm = bitmap_weight(matrix_mdev->matrix.aqm, AP_DOMAINS); > > @@ -741,7 +743,7 @@ static bool vfio_ap_mdev_assign_apqis_4_apid(struct > ap_matrix_mdev *matrix_mdev, > > for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) { > if (!test_bit_inv(apqi, > - (unsigned long *) matrix_dev->info.aqm)) > + (unsigned long *)matrix_dev->config_info.aqm)) > clear_bit_inv(apqi, aqm); > > apqn = AP_MKQID(apid, apqi); > @@ -764,7 +766,7 @@ static bool vfio_ap_mdev_assign_guest_apid(struct > ap_matrix_mdev *matrix_mdev, > unsigned long apqi, apqn; > > if (!vfio_ap_mdev_has_crycb(matrix_mdev) || > - !test_bit_inv(apid, (unsigned long *)matrix_dev->info.apm)) > + !test_bit_inv(apid, (unsigned long *)matrix_dev->config_info.apm)) > return false; > > if (bitmap_empty(matrix_mdev->shadow_apcb.aqm, AP_DOMAINS)) > @@ -931,8 +933,8 @@ static bool vfio_ap_mdev_assign_apids_4_apqi(struct > ap_matrix_mdev *matrix_mdev, > bitmap_copy(apm, matrix_mdev->matrix.apm, AP_DEVICES); > > for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) { > - if (!test_bit_inv(apid, > - (unsigned long *) matrix_dev->info.apm)) > + if (!test_bit_inv(apid, (unsigned long *) > + matrix_dev->config_info.apm)) > clear_bit_inv(apqi, apm); > > apqn = AP_MKQID(apid, apqi); > @@ -955,7 +957,7 @@ static bool vfio_ap_mdev_assign_guest_apqi(struct > ap_matrix_mdev *matrix_mdev, > unsigned long apid, apqn; > > if (!vfio_ap_mdev_has_crycb(matrix_mdev) || > - !test_bit_inv(apqi, (unsigned long *)matrix_dev->info.aqm)) > + !test_bit_inv(apqi, (unsigned long *)matrix_dev->config_info.aqm)) > return false; > > if (bitmap_empty(matrix_mdev->shadow_apcb.apm, AP_DEVICES)) > @@ -1702,7 +1704,7 @@ int vfio_ap_mdev_probe_queue(struct ap_queue *queue) > void vfio_ap_mdev_remove_queue(struct ap_queue *queue) > { > struct vfio_ap_queue *q; > - int apid, apqi; > + unsigned long apid, apqi; > Unrelated? > mutex_lock(&matrix_dev->lock); > q = dev_get_drvdata(&queue->ap_dev.device); > @@ -1727,3 +1729,126 @@ bool vfio_ap_mdev_resource_in_use(unsigned long *apm, > unsigned long *aqm) > > return in_use; > } > + > +/** > + * vfio_ap_mdev_unassign_apids > + * > + * @matrix_mdev: The matrix mediated device > + * > + * @aqm: A bitmap with 256 bits. Each bit in the map represents an APID from > 0 > + * to 255 (with the leftmost bit corresponding to APID 0). > + * > + * Unassigns each APID specified in @aqm that is assigned to the shadow CRYCB > + * of @matrix_mdev. Returns true if at least one APID is unassigned; > otherwise, > + * returns false. > + */ > +static bool vfio_ap_mdev_unassign_apids(struct ap_matrix_mdev *matrix_mdev, > + unsigned long *apm_unassign) > +{ > + unsigned long apid; > + bool unassigned = false; > + > + /* > + * If the matrix mdev is not in use by a KVM guest, return indicating > + * that no APIDs have been unassigned. > + */ > + if (!vfio_ap_mdev_has_crycb(matrix_mdev)) > + return false; > + > + for_each_set_bit_inv(apid, apm_unassign, AP_DEVICES) { > + unassigned |= vfio_ap_mdev_unassign_guest_apid(matrix_mdev, > + apid); > + } I guess, we could accomplish the unassign with operations operating on full bitmaps (without looping over bits), but I have no strong opinion here. > + > + return unassigned; > +} > + > +/** > + * vfio_ap_mdev_unassign_apqis > + * > + * @matrix_mdev: The matrix mediated device > + * > + * @aqm: A bitmap with 256 bits. Each bit in the map represents an APQI from > 0 > + * to 255 (with the leftmost bit corresponding to APQI 0). > + * > + * Unassigns each APQI specified in @aqm that is assigned to the shadow CRYCB > + * of @matrix_mdev. Returns true if at least one APQI is unassigned; > otherwise, > + * returns false. > + */ > +static bool vfio_ap_mdev_unassign_apqis(struct ap_matrix_mdev *matrix_mdev, > + unsigned long *aqm_unassign) > +{ > + unsigned long apqi; > + bool unassigned = false; > + > + /* > + * If the matrix mdev is not in use by a KVM guest, return indicating > + * that no APQIs have been unassigned. > + */ > + if (!vfio_ap_mdev_has_crycb(matrix_mdev)) > + return false; > + > + for_each_set_bit_inv(apqi, aqm_unassign, AP_DOMAINS) { > + unassigned |= vfio_ap_mdev_unassign_guest_apqi(matrix_mdev, > + apqi); > + } > + > + return unassigned; > +} > + > +void vfio_ap_on_cfg_changed(struct ap_config_info *new_config_info, > + struct ap_config_info *old_config_info) > +{ > + bool unassigned; > + int ap_remove, aq_remove; > + struct ap_matrix_mdev *matrix_mdev; > + DECLARE_BITMAP(apm_unassign, AP_DEVICES); > + DECLARE_BITMAP(aqm_unassign, AP_DOMAINS); > + > + unsigned long *cur_apm, *cur_aqm, *prev_apm, *prev_aqm; > + > + if (matrix_dev->flags & AP_MATRIX_CFG_CHG) { > + WARN_ONCE(1, "AP host configuration change already reported"); > + return; > + } > + > + memcpy(&matrix_dev->config_info, new_config_info, > + sizeof(struct ap_config_info)); > + memcpy(&matrix_dev->config_info_prev, old_config_info, > + sizeof(struct ap_config_info)); > + > + cur_apm = (unsigned long *)matrix_dev->config_info.apm; > + cur_aqm = (unsigned long *)matrix_dev->config_info.aqm; > + prev_apm = (unsigned long *)matrix_dev->config_info_prev.apm; > + prev_aqm = (unsigned long *)matrix_dev->config_info_prev.aqm; > + > + ap_remove = bitmap_andnot(apm_unassign, prev_apm, cur_apm, AP_DEVICES); > + aq_remove = bitmap_andnot(aqm_unassign, prev_aqm, cur_aqm, AP_DOMAINS); > + > + mutex_lock(&matrix_dev->lock); > + matrix_dev->flags |= AP_MATRIX_CFG_CHG; > + > + list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) { > + if (!vfio_ap_mdev_has_crycb(matrix_mdev)) > + continue; > + > + unassigned = false; > + > + if (ap_remove) > + if (bitmap_intersects(matrix_mdev->shadow_apcb.apm, > + apm_unassign, AP_DEVICES)) > + if (vfio_ap_mdev_unassign_apids(matrix_mdev, > + apm_unassign)) This can be done with a single "if". if (A) if (B) if (C) D; should be equivalent with if (A && B && C) D; and your wouldn't end up that deep indentation. It is a style thing, so unless regulated by the official coding style, it is up to you :) > + unassigned = true; > + if (aq_remove) > + if (bitmap_intersects(matrix_mdev->shadow_apcb.aqm, > + aqm_unassign, AP_DOMAINS)) > + if (vfio_ap_mdev_unassign_apqis(matrix_mdev, > + aqm_unassign)) > + unassigned = true; > + > + if (unassigned) > + vfio_ap_mdev_commit_shadow_apcb(matrix_mdev); > + } > + mutex_unlock(&matrix_dev->lock); > +} > diff --git a/drivers/s390/crypto/vfio_ap_private.h > b/drivers/s390/crypto/vfio_ap_private.h > index 055bce6d45db..fc8629e28ad3 100644 > --- a/drivers/s390/crypto/vfio_ap_private.h > +++ b/drivers/s390/crypto/vfio_ap_private.h > @@ -40,10 +40,13 @@ > struct ap_matrix_dev { > struct device device; > atomic_t available_instances; > - struct ap_config_info info; > + struct ap_config_info config_info; > + struct ap_config_info config_info_prev; > struct list_head mdev_list; > struct mutex lock; > struct ap_driver *vfio_ap_drv; > + #define AP_MATRIX_CFG_CHG (1UL << 0) > + unsigned long flags; > }; > > extern struct ap_matrix_dev *matrix_dev; > @@ -108,5 +111,7 @@ int vfio_ap_mdev_probe_queue(struct ap_queue *queue); > void vfio_ap_mdev_remove_queue(struct ap_queue *queue); > > bool vfio_ap_mdev_resource_in_use(unsigned long *apm, unsigned long *aqm); > +void vfio_ap_on_cfg_changed(struct ap_config_info *new_config_info, > + struct ap_config_info *old_config_info); > > #endif /* _VFIO_AP_PRIVATE_H_ */
