diff --git a/include/asm-sparc64/processor.h b/include/asm-sparc64/processor.h
index 8da484c19822cc1d08d59d4fc635e06329ef2675..885b6a1dcae4d0b75df49cdc82df8e2035aa45a0 100644
--- a/include/asm-sparc64/processor.h
+++ b/include/asm-sparc64/processor.h
@@ -37,6 +37,9 @@
 #endif
 
 #define TASK_SIZE	((unsigned long)-VPTE_SIZE)
+#define TASK_SIZE_OF(tsk) \
+	(test_tsk_thread_flag(tsk,TIF_32BIT) ? \
+	 (1UL << 32UL) : TASK_SIZE)
 #ifdef __KERNEL__
 
 #define STACK_TOP32	((1UL << 32UL) - PAGE_SIZE)