File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/blackfin/include/asm/l1layout.h b/arch/blackfin/include/asm/l1layout.h
new file mode 100644
index 0000000..c87e686
--- /dev/null
+++ b/arch/blackfin/include/asm/l1layout.h
@@ -0,0 +1,37 @@
+/*
+ * Defines a layout of L1 scratchpad memory that userspace can rely on.
+ *
+ * Copyright 2006-2008 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#ifndef _L1LAYOUT_H_
+#define _L1LAYOUT_H_
+
+#include <asm/blackfin.h>
+
+#ifndef CONFIG_SMP
+#ifndef __ASSEMBLY__
+
+/* Data that is "mapped" into the process VM at the start of the L1 scratch
+   memory, so that each process can access it at a fixed address.  Used for
+   stack checking.  */
+struct l1_scratch_task_info
+{
+	/* Points to the start of the stack.  */
+	void *stack_start;
+	/* Not updated by the kernel; a user process can modify this to
+	   keep track of the lowest address of the stack pointer during its
+	   runtime.  */
+	void *lowest_sp;
+};
+
+/* A pointer to the structure in memory.  */
+#define L1_SCRATCH_TASK_INFO ((struct l1_scratch_task_info *)\
+						get_l1_scratch_start())
+
+#endif
+#endif
+
+#endif