[S390] cio: Use device_schedule_callback() for removing disconnected devices.

We can't deregister disconnected and orphaned devices directly from
the online attribute's store method, but must take a detour.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 38 insertions, 11 deletions

diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index a8b373f69cf0..6b264bdb5bfb 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -296,30 +296,57 @@ static void ccw_device_unregister(struct ccw_device *cdev)
                 device_del(&cdev->dev);
 }
 
+static void ccw_device_remove_orphan_cb(struct device *dev)
+{
+        struct ccw_device *cdev = to_ccwdev(dev);
+
+        ccw_device_unregister(cdev);
+        put_device(&cdev->dev);
+}
+
+static void ccw_device_remove_sch_cb(struct device *dev)
+{
+        struct subchannel *sch;
+
+        sch = to_subchannel(dev);
+        css_sch_device_unregister(sch);
+        /* Reset intparm to zeroes. */
+        sch->schib.pmcw.intparm = 0;
+        cio_modify(sch);
+        put_device(&sch->dev);
+}
+
 static void
 ccw_device_remove_disconnected(struct ccw_device *cdev)
 {
-        struct subchannel *sch;
         unsigned long flags;
+        int rc;
+
         /*
          * Forced offline in disconnected state means
          * 'throw away device'.
          */
         if (ccw_device_is_orphan(cdev)) {
-                /* Deregister ccw device. */
+                /*
+                 * Deregister ccw device.
+                 * Unfortunately, we cannot do this directly from the
+                 * attribute method.
+                 */
                 spin_lock_irqsave(cdev->ccwlock, flags);
                 cdev->private->state = DEV_STATE_NOT_OPER;
                 spin_unlock_irqrestore(cdev->ccwlock, flags);
-                ccw_device_unregister(cdev);
-                put_device(&cdev->dev);
-                return ;
+                rc = device_schedule_callback(&cdev->dev,
+                                              ccw_device_remove_orphan_cb);
+                if (rc)
+                        dev_info(&cdev->dev, "Couldn't unregister orphan\n");
+                return;
         }
-        sch = to_subchannel(cdev->dev.parent);
-        css_sch_device_unregister(sch);
-        /* Reset intparm to zeroes. */
-        sch->schib.pmcw.intparm = 0;
-        cio_modify(sch);
-        put_device(&sch->dev);
+        /* Deregister subchannel, which will kill the ccw device. */
+        rc = device_schedule_callback(cdev->dev.parent,
+                                      ccw_device_remove_sch_cb);
+        if (rc)
+                dev_info(&cdev->dev,
+                         "Couldn't unregister disconnected device\n");
 }
 
 int