From: Parav Pandit <parav@xxxxxxxxxx> [ Upstream commit 0e0348ac3f0a6e6606f1aa5acb1803ada913aa3d ] 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> Message-Id: <20220613195223.473966-1-parav@xxxxxxxxxx> Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx> Reviewed-by: Xie Yongji <xieyongji@xxxxxxxxxxxxx> Acked-by: Jason Wang <jasowang@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- 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 160e40d03084..02709f8a78bd 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -1475,16 +1475,12 @@ 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) { @@ -1509,7 +1505,7 @@ 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; } @@ -1555,34 +1551,52 @@ 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) -- 2.35.1