On Tue, Jun 14, 2022 at 3:52 AM Parav Pandit <parav@xxxxxxxxxx> wrote: > > vduse devices are not backed by any real devices such as PCI. Hence it > doesn't have any parent device linked to it. > > Kernel driver model in [1] suggests to avoid an empty device > release callback. > > Hence tie the mgmtdevice object's life cycle to an allocate dummy struct > device instead of static one. > > [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/core-api/kobject.rst?h=v5.18-rc7#n284 > > Signed-off-by: Parav Pandit <parav@xxxxxxxxxx> Acked-by: Jason Wang <jasowang@xxxxxxxxxx> > --- > changelog: > v0->v1: > - removed typo in device name of "-la" > --- > drivers/vdpa/vdpa_user/vduse_dev.c | 60 ++++++++++++++++++------------ > 1 file changed, 37 insertions(+), 23 deletions(-) > > diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c > index 776ad7496f53..3bc27de58f46 100644 > --- a/drivers/vdpa/vdpa_user/vduse_dev.c > +++ b/drivers/vdpa/vdpa_user/vduse_dev.c > @@ -1476,16 +1476,12 @@ static char *vduse_devnode(struct device *dev, umode_t *mode) > return kasprintf(GFP_KERNEL, "vduse/%s", dev_name(dev)); > } > > -static void vduse_mgmtdev_release(struct device *dev) > -{ > -} > - > -static struct device vduse_mgmtdev = { > - .init_name = "vduse", > - .release = vduse_mgmtdev_release, > +struct vduse_mgmt_dev { > + struct vdpa_mgmt_dev mgmt_dev; > + struct device dev; > }; > > -static struct vdpa_mgmt_dev mgmt_dev; > +static struct vduse_mgmt_dev *vduse_mgmt; > > static int vduse_dev_init_vdpa(struct vduse_dev *dev, const char *name) > { > @@ -1510,7 +1506,7 @@ static int vduse_dev_init_vdpa(struct vduse_dev *dev, const char *name) > } > set_dma_ops(&vdev->vdpa.dev, &vduse_dev_dma_ops); > vdev->vdpa.dma_dev = &vdev->vdpa.dev; > - vdev->vdpa.mdev = &mgmt_dev; > + vdev->vdpa.mdev = &vduse_mgmt->mgmt_dev; > > return 0; > } > @@ -1556,34 +1552,52 @@ static struct virtio_device_id id_table[] = { > { 0 }, > }; > > -static struct vdpa_mgmt_dev mgmt_dev = { > - .device = &vduse_mgmtdev, > - .id_table = id_table, > - .ops = &vdpa_dev_mgmtdev_ops, > -}; > +static void vduse_mgmtdev_release(struct device *dev) > +{ > + struct vduse_mgmt_dev *mgmt_dev; > + > + mgmt_dev = container_of(dev, struct vduse_mgmt_dev, dev); > + kfree(mgmt_dev); > +} > > static int vduse_mgmtdev_init(void) > { > int ret; > > - ret = device_register(&vduse_mgmtdev); > - if (ret) > + vduse_mgmt = kzalloc(sizeof(*vduse_mgmt), GFP_KERNEL); > + if (!vduse_mgmt) > + return -ENOMEM; > + > + ret = dev_set_name(&vduse_mgmt->dev, "vduse"); > + if (ret) { > + kfree(vduse_mgmt); > return ret; > + } > > - ret = vdpa_mgmtdev_register(&mgmt_dev); > + vduse_mgmt->dev.release = vduse_mgmtdev_release; > + > + ret = device_register(&vduse_mgmt->dev); > if (ret) > - goto err; > + goto dev_reg_err; > > - return 0; > -err: > - device_unregister(&vduse_mgmtdev); > + vduse_mgmt->mgmt_dev.id_table = id_table; > + vduse_mgmt->mgmt_dev.ops = &vdpa_dev_mgmtdev_ops; > + vduse_mgmt->mgmt_dev.device = &vduse_mgmt->dev; > + ret = vdpa_mgmtdev_register(&vduse_mgmt->mgmt_dev); > + if (ret) > + device_unregister(&vduse_mgmt->dev); > + > + return ret; > + > +dev_reg_err: > + put_device(&vduse_mgmt->dev); > return ret; > } > > static void vduse_mgmtdev_exit(void) > { > - vdpa_mgmtdev_unregister(&mgmt_dev); > - device_unregister(&vduse_mgmtdev); > + vdpa_mgmtdev_unregister(&vduse_mgmt->mgmt_dev); > + device_unregister(&vduse_mgmt->dev); > } > > static int vduse_init(void) > -- > 2.26.2 > _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
