1 files changed, 16 insertions, 4 deletions

diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 2970022faa63..4427e0454051 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -191,6 +191,18 @@ struct dm_target {
 
         /* Used to provide an error string from the ctr */
         char *error;
+
+        /*
+         * Set if this target needs to receive discards regardless of
+         * whether or not its underlying devices have support.
+         */
+        unsigned discards_supported:1;
+};
+
+/* 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);
 };
 
 int dm_register_target(struct target_type *t);
@@ -269,14 +281,14 @@ int dm_table_add_target(struct dm_table *t, const char *type,
                         sector_t start, sector_t len, char *params);
 
 /*
- * Finally call this to make the table ready for use.
+ * Target_ctr should call this if it needs to add any callbacks.
  */
-int dm_table_complete(struct dm_table *t);
+void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callbacks *cb);
 
 /*
- * Unplug all devices in a table.
+ * Finally call this to make the table ready for use.
  */
-void dm_table_unplug_all(struct dm_table *t);
+int dm_table_complete(struct dm_table *t);
 
 /*
  * Table reference counting.