[S390] cio: ccwgroup register vs. unregister.
Introduce a mutex for struct ccwgroup to prevent simuntaneous
register/unregister on the same ccwgroup device.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/include/asm-s390/ccwgroup.h b/include/asm-s390/ccwgroup.h
index d2f9c0d..925b3dd 100644
--- a/include/asm-s390/ccwgroup.h
+++ b/include/asm-s390/ccwgroup.h
@@ -11,6 +11,7 @@
CCWGROUP_ONLINE,
} state;
atomic_t onoff;
+ struct mutex reg_mutex;
unsigned int count; /* number of attached slave devices */
struct device dev; /* master device */
struct ccw_device *cdev[0]; /* variable number, allocate as needed */