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Herne" In-Reply-To: <20260807221834.562851-6-akrowiak@linux.ibm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwODEzMDA4MSBTYWx0ZWRfX2w2RoOsNRsJO zy4SQsNBjxTHcBv2EqXAwzF1BWfhfSv5EvoabZT2RDFSIqEkUixmC7rEzILCN1iB6cRuax4h6Gq IPqpUgmOtzZr/iNRblopZS9LH14xOMZ4/w68CJv/UFKEvQwrLkiKc2P6eY+pbqFUAjPEVlk/17W /+cis75XLIpRp5XRkeZrUgw0iPeLSl+FmLSiMbG00ge5EaAxK4OBgYTis+oz6UTv+Bqo1gP58OP alfY1KUy9gc7OAgG4vK9l16TnUorFuN5PDUOGLWTGV5+QrWEnT+u0E6YOU3aPGKYAdMUqT3/EsK YnzY8d3Hno3uYyXrewwvtvIBXpDmK/nbYUxteBDyGxPnULOYiWEy8OAX1tjBBubwsRRjdeP9aXe 93u1Yxn1O6ZFKl7G0eh07UliSwXS0em1UXtxiO7h2S1selNPNPoCaD7fjHjz7MShPWy5zz/PEnU odfuqtHUI0dtBer9b1Q== X-Proofpoint-ORIG-GUID: VnxFgVyCPhP2q2xF0VXf7bnsoTknamym X-Proofpoint-Spam-Info: AW1haW4tMjYwODEzMDA4MSBTYWx0ZWRfX+90hGFRshwFa IFy4E5GSufiwTLTwEWk2fdm4n3tz34Au1GcMOpyNPVwg5bI8NmQwnxvtV7m7tvPCU6gfACmhmdA ePiXgDjhulRy5sFinXyxfPzTcQnXobc= X-Authority-Analysis: v=2.4 cv=IfK3n2qa c=1 sm=1 tr=0 ts=6a7db0a2 cx=c_pps a=3Bg1Hr4SwmMryq2xdFQyZA==:117 a=3Bg1Hr4SwmMryq2xdFQyZA==:17 a=IkcTkHD0fZMA:10 a=Sv0fKeRqtYgA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=U7nrCbtTmkRpXpFmAIza:22 a=VnNF1IyMAAAA:8 a=nxkqimRYtrKaij7qo54A:9 a=QEXdDO2ut3YA:10 X-Proofpoint-GUID: VnxFgVyCPhP2q2xF0VXf7bnsoTknamym X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-08-13_03,2026-08-12_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 priorityscore=1501 impostorscore=0 bulkscore=0 clxscore=1011 lowpriorityscore=0 adultscore=0 malwarescore=0 spamscore=0 suspectscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2608130081 On 8/7/26 6:18 PM, Anthony Krowiak wrote: > Implements two callbacks related to the current state of a vfio-ap device: > * The callback that sets a new migration state of a vfio-ap device during > live migration of guests with pass-through access to AP devices. This > callback is mandatory for VFIO_DEVICE_FEATURE_MIGRATION support. > > The function pointer for this callback is specified via the > 'migration_set_state' field of the 'vfio_migration_ops' structure > which is stored with the VFIO device when the 'vfio_device' > structure representing the mediated device is initialized. > > * The callback that returns the current vfio device migration state during > live migration of guests with pass-through access to AP devices. > > The function pointer for this callback is specified via the > 'migration_get_state' field of the 'vfio_migration_ops' structure > which is stored with the VFIO device when the 'vfio_device' > structure representing the mediated device is initialized. > > Signed-off-by: Anthony Krowiak > --- > drivers/s390/crypto/vfio_ap_migration.c | 130 +++++++++++++++++++++++- > 1 file changed, 128 insertions(+), 2 deletions(-) > > diff --git a/drivers/s390/crypto/vfio_ap_migration.c b/drivers/s390/crypto/vfio_ap_migration.c > index 1613813124b6..af740b177c97 100644 > --- a/drivers/s390/crypto/vfio_ap_migration.c > +++ b/drivers/s390/crypto/vfio_ap_migration.c > @@ -128,16 +128,141 @@ static void vfio_ap_release_resuming_file(struct vfio_ap_migration_data *mig_dat > */ > } > > +static struct file * > +vfio_ap_transition_to_state(struct ap_matrix_mdev *matrix_mdev, > + enum vfio_device_mig_state new_state) > +{ > + struct vfio_ap_migration_data *mig_data; > + enum vfio_device_mig_state cur_state; > + > + lockdep_assert_held(&matrix_dev->mdevs_lock); > + mig_data = matrix_mdev->mig_data; > + cur_state = mig_data->mig_state; > + dev_dbg(matrix_mdev->vdev.dev, "%s: %d -> %d\n", __func__, cur_state, > + new_state); > + > + if (cur_state == VFIO_DEVICE_STATE_STOP && > + new_state == VFIO_DEVICE_STATE_STOP_COPY) { > + /* TODO */ > + return ERR_PTR(-EOPNOTSUPP); > + } > + > + if (cur_state == VFIO_DEVICE_STATE_STOP && > + new_state == VFIO_DEVICE_STATE_RESUMING) { > + /* TODO */ > + return ERR_PTR(-EOPNOTSUPP); > + } > + > + if ((cur_state == VFIO_DEVICE_STATE_RESUMING && > + new_state == VFIO_DEVICE_STATE_STOP) || > + (cur_state == VFIO_DEVICE_STATE_STOP_COPY && > + new_state == VFIO_DEVICE_STATE_STOP)) { > + /* TODO */ > + return ERR_PTR(-EOPNOTSUPP); > + } > + > + if ((cur_state == VFIO_DEVICE_STATE_STOP && > + new_state == VFIO_DEVICE_STATE_RUNNING) || > + (cur_state == VFIO_DEVICE_STATE_RUNNING && > + new_state == VFIO_DEVICE_STATE_STOP)) { > + /* TODO */ > + return ERR_PTR(-EOPNOTSUPP); > + } > + > + /* vfio_mig_get_next_state() does not use arcs other than the above */ > + WARN_ON(true); > + > + return ERR_PTR(-EINVAL); > +} > + > static struct file *vfio_ap_set_state(struct vfio_device *vdev, > enum vfio_device_mig_state new_state) > { > - return NULL; > + int ret; > + struct file *filp = NULL; > + struct ap_matrix_mdev *matrix_mdev; > + enum vfio_device_mig_state next_state; > + struct vfio_ap_migration_data *mig_data; > + > + matrix_mdev = container_of(vdev, struct ap_matrix_mdev, vdev); The container_of() pointer swizzle is done under lock in vfio_ap_get_state, but not here. Why? They should probably be handled consistently. > + > + mutex_lock(&matrix_dev->mdevs_lock); > + if (ap_is_se_guest()) { > + dev_err_once(matrix_mdev->vdev.dev, > + "Migration not allowed from or to a Secure Execution guest\n"); > + mutex_unlock(&matrix_dev->mdevs_lock); > + return ERR_PTR(-EPERM); > + } > + > + mig_data = matrix_mdev->mig_data; > + > + /* > + * The mig_data pointer is set in the vfio_ap_init_migration_data > + * function which is called when the vfio-ap device fd is opened. > + * Since the implicit pre-open state is RUNNING, a request to set > + * RUNNING is a no-op. Any other state transition is invalid before > + * open_device. > + */ > + if (!mig_data) { > + mutex_unlock(&matrix_dev->mdevs_lock); > + if (new_state == VFIO_DEVICE_STATE_RUNNING) > + return NULL; > + return ERR_PTR(-ENODEV); > + } > + > + dev_dbg(vdev->dev, "%s -> %d\n", __func__, new_state); > + > + while (mig_data->mig_state != VFIO_DEVICE_STATE_ERROR && > + mig_data->mig_state != new_state) { > + ret = vfio_mig_get_next_state(vdev, mig_data->mig_state, > + new_state, &next_state); > + if (ret) { > + filp = ERR_PTR(ret); > + break; > + } > + > + filp = vfio_ap_transition_to_state(matrix_mdev, next_state); > + if (IS_ERR(filp)) > + break; > + > + mig_data->mig_state = next_state; > + > + if (WARN_ON(filp && new_state != next_state)) { > + fput(filp); > + filp = ERR_PTR(-EINVAL); > + break; > + } > + } > + > + mutex_unlock(&matrix_dev->mdevs_lock); > + > + return filp; > } > > static int vfio_ap_get_state(struct vfio_device *vdev, > enum vfio_device_mig_state *current_state) > { > - return -EOPNOTSUPP; > + struct ap_matrix_mdev *matrix_mdev; > + struct vfio_ap_migration_data *mig_data; > + > + mutex_lock(&matrix_dev->mdevs_lock); > + > + matrix_mdev = container_of(vdev, struct ap_matrix_mdev, vdev); > + mig_data = matrix_mdev->mig_data; Why bother with temp variable? You could just access matrix_mdev->mig_data directly. > + > + /* > + * The mig_data pointer is set in the vfio_ap_init_migration_data > + * function which is called when the vfio-ap device fd is opened. > + * If mig_data is NULL, report RUNNING as the implicit pre-open state > + * so userspace doesn't need to perform any state transition before the > + * device becomes active. > + */ > + *current_state = (mig_data) ? mig_data->mig_state : > + VFIO_DEVICE_STATE_RUNNING; > + > + mutex_unlock(&matrix_dev->mdevs_lock); > + > + return 0; > } > > static int vfio_ap_get_data_size(struct vfio_device *vdev, > @@ -159,6 +284,7 @@ static const struct vfio_migration_ops vfio_ap_migration_ops = { > */ > void vfio_ap_init_migration_capabilities(struct ap_matrix_mdev *matrix_mdev) > { > + /* Live guest migration is not supported for SE guests */ > if (ap_is_se_guest()) > return; > Comment is unrelated to the rest of the patch.