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-rw-r--r--arch/unicore32/lib/strnlen_user.S42
1 files changed, 42 insertions, 0 deletions
diff --git a/arch/unicore32/lib/strnlen_user.S b/arch/unicore32/lib/strnlen_user.S
new file mode 100644
index 000000000000..75863030f21d
--- /dev/null
+++ b/arch/unicore32/lib/strnlen_user.S
@@ -0,0 +1,42 @@
+/*
+ * linux/arch/unicore32/lib/strnlen_user.S
+ *
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ * Copyright (C) 2001-2010 GUAN Xue-tao
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/errno.h>
+
+ .text
+ .align 5
+
+/* Prototype: unsigned long __strnlen_user(const char *str, long n)
+ * Purpose : get length of a string in user memory
+ * Params : str - address of string in user memory
+ * Returns : length of string *including terminator*
+ * or zero on exception, or n + 1 if too long
+ */
+ENTRY(__strnlen_user)
+ mov r2, r0
+1:
+ ldrusr r3, r0, 1
+ cxor.a r3, #0
+ beq 2f
+ sub.a r1, r1, #1
+ bne 1b
+ add r0, r0, #1
+2: sub r0, r0, r2
+ mov pc, lr
+ENDPROC(__strnlen_user)
+
+ .pushsection .fixup,"ax"
+ .align 0
+9001: mov r0, #0
+ mov pc, lr
+ .popsection