Revert "scsi: use device_remove_file_self() instead of device_schedule_callback()"

This reverts commit de1dee7820.

Tejun writes:
        I'm sorry but can you please revert the whole series?
        get_active() waiting while a node is deactivated has potential
        to lead to deadlock and that deactivate/reactivate interface is
        something fundamentally flawed and that cgroup will have to work
        with the remove_self() like everybody else.  IOW, I think the
        first posting was correct.

Cc: Tejun Heo <tj@kernel.org>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/scsi/scsi_sysfs.c

@@ -635,12 +635,23 @@ store_rescan_field (struct device *dev, struct device_attribute *attr,
 }
 static DEVICE_ATTR(rescan, S_IWUSR, NULL, store_rescan_field);
 
+static void sdev_store_delete_callback(struct device *dev)
+{
+	scsi_remove_device(to_scsi_device(dev));
+}
+
 static ssize_t
 sdev_store_delete(struct device *dev, struct device_attribute *attr,
 		  const char *buf, size_t count)
 {
-	if (device_remove_file_self(dev, attr))
-		scsi_remove_device(to_scsi_device(dev));
+	int rc;
+
+	/* An attribute cannot be unregistered by one of its own methods,
+	 * so we have to use this roundabout approach.
+	 */
+	rc = device_schedule_callback(dev, sdev_store_delete_callback);
+	if (rc)
+		count = rc;
 	return count;
 };
 static DEVICE_ATTR(delete, S_IWUSR, NULL, sdev_store_delete);