Prefaulting of utcb pages seem to work.

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

tasks/mm0/include/task.h

@@ -68,8 +68,9 @@ struct tcb {
 	unsigned long map_start;
 	unsigned long map_end;
 
-	/* UTCB address */
+	/* UTCB information */
 	unsigned long utcb_address;
+	int utcb_mapped;
 
 	/* Virtual memory areas */
 	struct list_head vm_area_list;
@@ -83,6 +84,6 @@ struct tcb *find_task(int tid);
 struct initdata;
 void init_pm(struct initdata *initdata);
 
-void send_task_data(l4id_t requester);
+int send_task_data(l4id_t requester);
 
 #endif /* __TASK_H__ */

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

tasks/mm0/include/vm_area.h

@@ -81,6 +81,7 @@ struct fault_data {
 	fault_kdata_t *kdata;		/* Generic data flonged by the kernel */
 	unsigned int reason;		/* Generic fault reason flags */
 	unsigned int address;		/* Aborted address */
+	unsigned int pte_flags;		/* Generic protection flags on pte */
 	struct vm_area *vma;		/* Inittask-related fault data */
 	struct tcb *task;		/* Inittask-related fault data */
 };
@@ -206,7 +207,14 @@ struct vm_file *vm_file_create(void);
 int vm_object_delete(struct vm_object *vmo);
 void vm_object_print(struct vm_object *vmo);
 
+/* Used for pre-faulting a page from mm0 */
+int prefault_page(struct tcb *task, unsigned long address,
+		  unsigned int vmflags);
+
+/* To get currently mapped page of a virtual address on a task */
+struct page *task_virt_to_page(struct tcb *t, unsigned long virtual);
+
 /* Main page fault entry point */
-void page_fault_handler(l4id_t tid, fault_kdata_t *fkdata);
+int page_fault_handler(l4id_t tid, fault_kdata_t *fkdata);
 
 #endif /* __VM_AREA_H__ */