Index: uspace/lib/c/include/fibril.h
===================================================================
--- uspace/lib/c/include/fibril.h	(revision 668f8cbff72b222492a3db956029fe7d751ab4af)
+++ uspace/lib/c/include/fibril.h	(revision 649efcd10c85afaeb282dd04ea32710ea1e24a4e)
@@ -48,4 +48,10 @@
 #define FIBRIL_WRITER      2
 
+struct fibril;
+
+typedef struct {
+	struct fibril *owned_by;
+} fibril_owner_info_t;
+
 typedef enum {
 	FIBRIL_PREEMPT,
@@ -68,4 +74,6 @@
 	int retval;
 	int flags;
+
+	fibril_owner_info_t *waits_for;
 } fibril_t;
 
Index: uspace/lib/c/include/fibril_synch.h
===================================================================
--- uspace/lib/c/include/fibril_synch.h	(revision 668f8cbff72b222492a3db956029fe7d751ab4af)
+++ uspace/lib/c/include/fibril_synch.h	(revision 649efcd10c85afaeb282dd04ea32710ea1e24a4e)
@@ -41,8 +41,4 @@
 #include <libarch/tls.h>
 #include <sys/time.h>
-
-typedef struct {
-	fibril_t *owned_by;
-} fibril_owner_info_t;
 
 typedef struct {