1 files changed, 6 insertions, 0 deletions

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 740126d7c44e..b5e1dcfbc5e3 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1815,6 +1815,11 @@ struct super_operations {
  *
  * I_DIO_WAKEUP         Never set.  Only used as a key for wait_on_bit().
  *
+ * I_WB_SWITCH          Cgroup bdi_writeback switching in progress.  Used to
+ *                      synchronize competing switching instances and to tell
+ *                      wb stat updates to grab mapping->tree_lock.  See
+ *                      inode_switch_wb_work_fn() for details.
+ *
  * Q: What is the difference between I_WILL_FREE and I_FREEING?
  */
 #define I_DIRTY_SYNC            (1 << 0)
@@ -1834,6 +1839,7 @@ struct super_operations {
 #define I_DIRTY_TIME            (1 << 11)
 #define __I_DIRTY_TIME_EXPIRED  12
 #define I_DIRTY_TIME_EXPIRED    (1 << __I_DIRTY_TIME_EXPIRED)
+#define I_WB_SWITCH             (1 << 13)
 
 #define I_DIRTY (I_DIRTY_SYNC | I_DIRTY_DATASYNC | I_DIRTY_PAGES)
 #define I_DIRTY_ALL (I_DIRTY | I_DIRTY_TIME)