On Wed, 17 Oct 2018 11:18:41 +0200 Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote: > The subchannel enablement and the according setting to the > VFIO_CCW_STATE_STANDBY state should only be done when all > parts of the VFIO mediated device have been initialized > i.e. after the mediated device has been successfully opened. > > Let's stay in VFIO_CCW_STATE_NOT_OPER until the mediated > device has been opened. > > When the mediated device is closed, disable the sub channel > by calling vfio_ccw_sch_quiesce(). > > Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx> > --- > drivers/s390/cio/vfio_ccw_drv.c | 10 +--------- > drivers/s390/cio/vfio_ccw_ops.c | 23 +++++++++++++++++++++-- > 2 files changed, 22 insertions(+), 11 deletions(-) (...) > diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c > index f673e10..87a8f8c 100644 > --- a/drivers/s390/cio/vfio_ccw_ops.c > +++ b/drivers/s390/cio/vfio_ccw_ops.c > @@ -146,11 +146,29 @@ static int vfio_ccw_mdev_open(struct mdev_device *mdev) > struct vfio_ccw_private *private = > dev_get_drvdata(mdev_parent_dev(mdev)); > unsigned long events = VFIO_IOMMU_NOTIFY_DMA_UNMAP; > + struct subchannel *sch = private->sch; > + int ret; > > private->nb.notifier_call = vfio_ccw_mdev_notifier; > > - return vfio_register_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, > - &events, &private->nb); > + ret = vfio_register_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, > + &events, &private->nb); > + if (ret) > + return ret; > + > + spin_lock_irq(private->sch->lock); > + if (cio_enable_subchannel(sch, (u32)(unsigned long)sch)) > + goto error; > + > + private->state = VFIO_CCW_STATE_STANDBY; > + spin_unlock_irq(sch->lock); > + return 0; > + > +error: > + spin_unlock_irq(sch->lock); > + vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, > + &private->nb); > + return -EFAULT; This -EFAULT looks a bit odd. Wouldn't it make more sense to relay the return code of cio_enable_subchannel() here? > } > > static void vfio_ccw_mdev_release(struct mdev_device *mdev) > @@ -158,6 +176,7 @@ static void vfio_ccw_mdev_release(struct mdev_device *mdev) > struct vfio_ccw_private *private = > dev_get_drvdata(mdev_parent_dev(mdev)); > > + vfio_ccw_sch_quiesce(private->sch); > vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, > &private->nb); > }
