UBI: add reboot notifier

Terminate the UBI background thread prior to restarting the system.

[Artem: amended comments a little]

Signed-off-by: Kevin Cernekee <kpc.mtd@gmail.com>
Tested-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h
index 70ce48b..28acd13 100644
--- a/drivers/mtd/ubi/ubi.h
+++ b/drivers/mtd/ubi/ubi.h
@@ -36,9 +36,9 @@
 #include <linux/device.h>
 #include <linux/string.h>
 #include <linux/vmalloc.h>
+#include <linux/notifier.h>
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/ubi.h>
-#include <linux/notifier.h>
 
 #include "ubi-media.h"
 #include "scan.h"
@@ -348,6 +348,7 @@
  * @bgt_thread: background thread description object
  * @thread_enabled: if the background thread is enabled
  * @bgt_name: background thread name
+ * @reboot_notifier: notifier to terminate background thread before rebooting
  *
  * @flash_size: underlying MTD device size (in bytes)
  * @peb_count: count of physical eraseblocks on the MTD device
@@ -431,6 +432,7 @@
 	struct task_struct *bgt_thread;
 	int thread_enabled;
 	char bgt_name[sizeof(UBI_BGT_NAME_PATTERN)+2];
+	struct notifier_block reboot_notifier;
 
 	/* I/O sub-system's stuff */
 	long long flash_size;