Prefaulting of utcb pages seem to work.

Next: fs0 should shmat() on others' utcbs.

tasks/mm0/include/utcb.h

@@ -2,6 +2,7 @@
 #define __MM0_UTCB_H__
 
 #include <l4lib/types.h>
+#include <task.h>
 void *utcb_vaddr_new(void);
 int utcb_pool_init(void);
 
@@ -9,4 +10,7 @@ int utcb_pool_init(void);
 /* IPC to send utcb address information to tasks */
 int task_send_utcb_address(l4id_t sender, l4id_t taskid);
 
+/* Prefault an *mmaped* utcb */
+int utcb_prefault(struct tcb *task, unsigned int vmflags);
+
 #endif