1 files changed, 12 insertions, 0 deletions

diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 2970022faa63..272496d1fae4 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -193,6 +193,13 @@ struct dm_target {
         char *error;
 };
 
+/* Each target can link one of these into the table */
+struct dm_target_callbacks {
+        struct list_head list;
+        int (*congested_fn) (struct dm_target_callbacks *, int);
+        void (*unplug_fn)(struct dm_target_callbacks *);
+};
+
 int dm_register_target(struct target_type *t);
 void dm_unregister_target(struct target_type *t);
 
@@ -269,6 +276,11 @@ int dm_table_add_target(struct dm_table *t, const char *type,
                         sector_t start, sector_t len, char *params);
 
 /*
+ * Target_ctr should call this if it needs to add any callbacks.
+ */
+void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callbacks *cb);
+
+/*
  * Finally call this to make the table ready for use.
  */
 int dm_table_complete(struct dm_table *t);