+static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
+{
+ struct ccw_device *cdev;
+
+ cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
+ if (cdev) {
+ cdev->private = kzalloc(sizeof(struct ccw_device_private),
+ GFP_KERNEL | GFP_DMA);
+ if (cdev->private)
+ return cdev;
+ }
+ kfree(cdev);
+ return ERR_PTR(-ENOMEM);
+}
+
+static int io_subchannel_initialize_dev(struct subchannel *sch,
+ struct ccw_device *cdev)
+{
+ cdev->private->cdev = cdev;
+ atomic_set(&cdev->private->onoff, 0);
+ cdev->dev.parent = &sch->dev;
+ cdev->dev.release = ccw_device_release;
+ INIT_LIST_HEAD(&cdev->private->kick_work.entry);
+ /* Do first half of device_register. */
+ device_initialize(&cdev->dev);
+ if (!get_device(&sch->dev)) {
+ if (cdev->dev.release)
+ cdev->dev.release(&cdev->dev);
+ return -ENODEV;
+ }
+ return 0;
+}
+
+static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
+{
+ struct ccw_device *cdev;
+ int ret;
+
+ cdev = io_subchannel_allocate_dev(sch);
+ if (!IS_ERR(cdev)) {
+ ret = io_subchannel_initialize_dev(sch, cdev);
+ if (ret) {
+ kfree(cdev);
+ cdev = ERR_PTR(ret);
+ }
+ }
+ return cdev;
+}
+
+static int io_subchannel_recog(struct ccw_device *, struct subchannel *);
+
+static void sch_attach_device(struct subchannel *sch,
+ struct ccw_device *cdev)
+{
+ spin_lock_irq(sch->lock);
+ sch->dev.driver_data = cdev;
+ cdev->private->schid = sch->schid;
+ cdev->ccwlock = sch->lock;
+ device_trigger_reprobe(sch);
+ spin_unlock_irq(sch->lock);
+}
+
+static void sch_attach_disconnected_device(struct subchannel *sch,
+ struct ccw_device *cdev)
+{
+ struct subchannel *other_sch;
+ int ret;
+
+ other_sch = to_subchannel(get_device(cdev->dev.parent));
+ ret = device_move(&cdev->dev, &sch->dev);
+ if (ret) {
+ CIO_MSG_EVENT(2, "Moving disconnected device 0.%x.%04x failed "
+ "(ret=%d)!\n", cdev->private->dev_id.ssid,
+ cdev->private->dev_id.devno, ret);
+ put_device(&other_sch->dev);
+ return;
+ }
+ other_sch->dev.driver_data = NULL;
+ /* No need to keep a subchannel without ccw device around. */
+ css_sch_device_unregister(other_sch);
+ put_device(&other_sch->dev);
+ sch_attach_device(sch, cdev);
+}
+
+static void sch_attach_orphaned_device(struct subchannel *sch,
+ struct ccw_device *cdev)
+{
+ int ret;
+
+ /* Try to move the ccw device to its new subchannel. */
+ ret = device_move(&cdev->dev, &sch->dev);
+ if (ret) {
+ CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
+ "failed (ret=%d)!\n",
+ cdev->private->dev_id.ssid,
+ cdev->private->dev_id.devno, ret);
+ return;
+ }
+ sch_attach_device(sch, cdev);
+}
+
+static void sch_create_and_recog_new_device(struct subchannel *sch)
+{
+ struct ccw_device *cdev;
+
+ /* Need to allocate a new ccw device. */
+ cdev = io_subchannel_create_ccwdev(sch);
+ if (IS_ERR(cdev)) {
+ /* OK, we did everything we could... */
+ css_sch_device_unregister(sch);
+ return;
+ }
+ spin_lock_irq(sch->lock);
+ sch->dev.driver_data = cdev;
+ spin_unlock_irq(sch->lock);
+ /* Start recognition for the new ccw device. */
+ if (io_subchannel_recog(cdev, sch)) {
+ spin_lock_irq(sch->lock);
+ sch->dev.driver_data = NULL;
+ spin_unlock_irq(sch->lock);
+ if (cdev->dev.release)
+ cdev->dev.release(&cdev->dev);
+ css_sch_device_unregister(sch);
+ }
+}
+
+
+void ccw_device_move_to_orphanage(struct work_struct *work)
+{
+ struct ccw_device_private *priv;
+ struct ccw_device *cdev;
+ struct ccw_device *replacing_cdev;
+ struct subchannel *sch;
+ int ret;
+ struct channel_subsystem *css;
+ struct ccw_dev_id dev_id;
+
+ priv = container_of(work, struct ccw_device_private, kick_work);
+ cdev = priv->cdev;
+ sch = to_subchannel(cdev->dev.parent);
+ css = to_css(sch->dev.parent);
+ dev_id.devno = sch->schib.pmcw.dev;
+ dev_id.ssid = sch->schid.ssid;
+
+ /*
+ * Move the orphaned ccw device to the orphanage so the replacing
+ * ccw device can take its place on the subchannel.
+ */
+ ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev);
+ if (ret) {
+ CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
+ "(ret=%d)!\n", cdev->private->dev_id.ssid,
+ cdev->private->dev_id.devno, ret);
+ return;
+ }
+ cdev->ccwlock = css->pseudo_subchannel->lock;
+ /*
+ * Search for the replacing ccw device
+ * - among the disconnected devices
+ * - in the orphanage
+ */
+ replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
+ if (replacing_cdev) {
+ sch_attach_disconnected_device(sch, replacing_cdev);
+ return;
+ }
+ replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
+ if (replacing_cdev) {
+ sch_attach_orphaned_device(sch, replacing_cdev);
+ return;
+ }
+ sch_create_and_recog_new_device(sch);
+}
+