Hi Diana, On 8/26/20 11:33 AM, Diana Craciun wrote: > The DPRC (Data Path Resource Container) device is a bus device and has > child devices attached to it. When the vfio-fsl-mc driver is probed > the DPRC is scanned and the child devices discovered and initialized. > > Signed-off-by: Bharat Bhushan <[email protected]> > Signed-off-by: Diana Craciun <[email protected]> > --- > drivers/vfio/fsl-mc/vfio_fsl_mc.c | 84 +++++++++++++++++++++++ > drivers/vfio/fsl-mc/vfio_fsl_mc_private.h | 1 + > 2 files changed, 85 insertions(+) > > diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c > b/drivers/vfio/fsl-mc/vfio_fsl_mc.c > index 8b53c2a25b32..85e007be3a5d 100644 > --- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c > +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c > @@ -15,6 +15,8 @@ > > #include "vfio_fsl_mc_private.h" > > +static struct fsl_mc_driver vfio_fsl_mc_driver; > + > static int vfio_fsl_mc_open(void *device_data) > { > if (!try_module_get(THIS_MODULE)) > @@ -84,6 +86,72 @@ static const struct vfio_device_ops vfio_fsl_mc_ops = { > .mmap = vfio_fsl_mc_mmap, > }; > > +static int vfio_fsl_mc_bus_notifier(struct notifier_block *nb, > + unsigned long action, void *data) > +{ > + struct vfio_fsl_mc_device *vdev = container_of(nb, > + struct vfio_fsl_mc_device, nb); > + struct device *dev = data; > + struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev); > + struct fsl_mc_device *mc_cont = to_fsl_mc_device(mc_dev->dev.parent); > + > + if (action == BUS_NOTIFY_ADD_DEVICE && > + vdev->mc_dev == mc_cont) { > + mc_dev->driver_override = kasprintf(GFP_KERNEL, "%s", > + vfio_fsl_mc_ops.name); > + if (!mc_dev->driver_override) > + dev_warn(dev, "Setting driver override for device in > dprc %s failed\n", > + dev_name(&mc_cont->dev)); > + dev_info(dev, "Setting driver override for device in dprc %s\n", > + dev_name(&mc_cont->dev)); Don't you miss an else here? > + } else if (action == BUS_NOTIFY_BOUND_DRIVER && > + vdev->mc_dev == mc_cont) { > + struct fsl_mc_driver *mc_drv = to_fsl_mc_driver(dev->driver); > + > + if (mc_drv && mc_drv != &vfio_fsl_mc_driver) > + dev_warn(dev, "Object %s bound to driver %s while DPRC > bound to vfio-fsl-mc\n", > + dev_name(dev), mc_drv->driver.name); > + } > + > + return 0; > +} > + > +static int vfio_fsl_mc_init_device(struct vfio_fsl_mc_device *vdev) > +{ > + struct fsl_mc_device *mc_dev = vdev->mc_dev; > + int ret; > + > + /* Non-dprc devices share mc_io from parent */ > + if (!is_fsl_mc_bus_dprc(mc_dev)) { > + struct fsl_mc_device *mc_cont = > to_fsl_mc_device(mc_dev->dev.parent); > + > + mc_dev->mc_io = mc_cont->mc_io; > + return 0; > + } > + > + vdev->nb.notifier_call = vfio_fsl_mc_bus_notifier; > + ret = bus_register_notifier(&fsl_mc_bus_type, &vdev->nb); > + if (ret) > + return ret; > + > + /* open DPRC, allocate a MC portal */ > + ret = dprc_setup(mc_dev); > + if (ret < 0) { if (ret) here and in other places? or are there any > returned values > + dev_err(&mc_dev->dev, "Failed to setup DPRC (error = %d)\n", > ret); nit: maybe align your error messages. Before you were using __func__, here you don't. Maybe don't? also you may consider using strerror(-ret) > + bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb); > + return ret; > + } > + > + ret = dprc_scan_container(mc_dev, false); > + if (ret < 0) { > + dev_err(&mc_dev->dev, "Container scanning failed: %d\n", ret); > + dprc_cleanup(mc_dev); I see dprc_cleanup is likely to fail. Generally cleanup shouldn't. https://www.mail-archive.com/[email protected]/msg2283433.html > + bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb); nit: here also you can factorize code doing goto unregister; shouldn't you reset vdev->nb.notifier_call to NULL as well. I see it is tested in other places. > + } > + > + return ret; > +} > + > static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev) > { > struct iommu_group *group; > @@ -112,6 +180,12 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device > *mc_dev) > return ret; > } > > + ret = vfio_fsl_mc_init_device(vdev); > + if (ret < 0) { I think you also need to call vfio_del_group_dev(&pdev->dev) > + vfio_iommu_group_put(group, dev); > + return ret; nit: goto put_group; > + } > + > return ret; > } > > @@ -124,6 +198,16 @@ static int vfio_fsl_mc_remove(struct fsl_mc_device > *mc_dev) > if (!vdev) > return -EINVAL; > > + if (vdev->nb.notifier_call) > + bus_unregister_notifier(&fsl_mc_bus_type, &vdev->nb); > + > + if (is_fsl_mc_bus_dprc(mc_dev)) { > + dprc_remove_devices(mc_dev, NULL, 0); > + dprc_cleanup(mc_dev); > + } you may consider doing the tear down in opposite order than vfio_fsl_mc_init_device, ie. bus_unregister_notifier after the dprc_cleanup? That's also what is done in vfio_fsl_mc_init_device error path handling. > + > + mc_dev->mc_io = NULL; > + > vfio_iommu_group_put(mc_dev->dev.iommu_group, dev); > > return 0; > diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h > b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h > index e79cc116f6b8..37d61eaa58c8 100644 > --- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h > +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h > @@ -9,6 +9,7 @@ > > struct vfio_fsl_mc_device { > struct fsl_mc_device *mc_dev; > + struct notifier_block nb; > }; > > #endif /* VFIO_FSL_MC_PRIVATE_H */> Thanks
Eric
